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Diffstat (limited to 'sys/cddl/contrib/opensolaris/uts/common/dtrace/dtrace.c')
| -rw-r--r-- | sys/cddl/contrib/opensolaris/uts/common/dtrace/dtrace.c | 18435 |
1 files changed, 18435 insertions, 0 deletions
diff --git a/sys/cddl/contrib/opensolaris/uts/common/dtrace/dtrace.c b/sys/cddl/contrib/opensolaris/uts/common/dtrace/dtrace.c new file mode 100644 index 000000000000..3d68a68ba819 --- /dev/null +++ b/sys/cddl/contrib/opensolaris/uts/common/dtrace/dtrace.c @@ -0,0 +1,18435 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License (the "License"). + * You may not use this file except in compliance with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + * + * $FreeBSD$ + */ + +/* + * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved. + * Copyright (c) 2016, Joyent, Inc. All rights reserved. + * Copyright (c) 2012, 2014 by Delphix. All rights reserved. + */ + +/* + * DTrace - Dynamic Tracing for Solaris + * + * This is the implementation of the Solaris Dynamic Tracing framework + * (DTrace). The user-visible interface to DTrace is described at length in + * the "Solaris Dynamic Tracing Guide". The interfaces between the libdtrace + * library, the in-kernel DTrace framework, and the DTrace providers are + * described in the block comments in the <sys/dtrace.h> header file. The + * internal architecture of DTrace is described in the block comments in the + * <sys/dtrace_impl.h> header file. The comments contained within the DTrace + * implementation very much assume mastery of all of these sources; if one has + * an unanswered question about the implementation, one should consult them + * first. + * + * The functions here are ordered roughly as follows: + * + * - Probe context functions + * - Probe hashing functions + * - Non-probe context utility functions + * - Matching functions + * - Provider-to-Framework API functions + * - Probe management functions + * - DIF object functions + * - Format functions + * - Predicate functions + * - ECB functions + * - Buffer functions + * - Enabling functions + * - DOF functions + * - Anonymous enabling functions + * - Consumer state functions + * - Helper functions + * - Hook functions + * - Driver cookbook functions + * + * Each group of functions begins with a block comment labelled the "DTrace + * [Group] Functions", allowing one to find each block by searching forward + * on capital-f functions. + */ +#include <sys/errno.h> +#include <sys/param.h> +#include <sys/types.h> +#ifndef illumos +#include <sys/time.h> +#endif +#include <sys/stat.h> +#include <sys/conf.h> +#include <sys/systm.h> +#include <sys/endian.h> +#ifdef illumos +#include <sys/ddi.h> +#include <sys/sunddi.h> +#endif +#include <sys/cpuvar.h> +#include <sys/kmem.h> +#ifdef illumos +#include <sys/strsubr.h> +#endif +#include <sys/sysmacros.h> +#include <sys/dtrace_impl.h> +#include <sys/atomic.h> +#include <sys/cmn_err.h> +#ifdef illumos +#include <sys/mutex_impl.h> +#include <sys/rwlock_impl.h> +#endif +#include <sys/ctf_api.h> +#ifdef illumos +#include <sys/panic.h> +#include <sys/priv_impl.h> +#endif +#ifdef illumos +#include <sys/cred_impl.h> +#include <sys/procfs_isa.h> +#endif +#include <sys/taskq.h> +#ifdef illumos +#include <sys/mkdev.h> +#include <sys/kdi.h> +#endif +#include <sys/zone.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include "strtolctype.h" + +/* FreeBSD includes: */ +#ifndef illumos +#include <sys/callout.h> +#include <sys/ctype.h> +#include <sys/eventhandler.h> +#include <sys/limits.h> +#include <sys/linker.h> +#include <sys/kdb.h> +#include <sys/jail.h> +#include <sys/kernel.h> +#include <sys/malloc.h> +#include <sys/lock.h> +#include <sys/mutex.h> +#include <sys/ptrace.h> +#include <sys/random.h> +#include <sys/rwlock.h> +#include <sys/sx.h> +#include <sys/sysctl.h> + + +#include <sys/mount.h> +#undef AT_UID +#undef AT_GID +#include <sys/vnode.h> +#include <sys/cred.h> + +#include <sys/dtrace_bsd.h> + +#include <netinet/in.h> + +#include "dtrace_cddl.h" +#include "dtrace_debug.c" +#endif + +#include "dtrace_xoroshiro128_plus.h" + +/* + * DTrace Tunable Variables + * + * The following variables may be tuned by adding a line to /etc/system that + * includes both the name of the DTrace module ("dtrace") and the name of the + * variable. For example: + * + * set dtrace:dtrace_destructive_disallow = 1 + * + * In general, the only variables that one should be tuning this way are those + * that affect system-wide DTrace behavior, and for which the default behavior + * is undesirable. Most of these variables are tunable on a per-consumer + * basis using DTrace options, and need not be tuned on a system-wide basis. + * When tuning these variables, avoid pathological values; while some attempt + * is made to verify the integrity of these variables, they are not considered + * part of the supported interface to DTrace, and they are therefore not + * checked comprehensively. Further, these variables should not be tuned + * dynamically via "mdb -kw" or other means; they should only be tuned via + * /etc/system. + */ +int dtrace_destructive_disallow = 0; +#ifndef illumos +/* Positive logic version of dtrace_destructive_disallow for loader tunable */ +int dtrace_allow_destructive = 1; +#endif +dtrace_optval_t dtrace_nonroot_maxsize = (16 * 1024 * 1024); +size_t dtrace_difo_maxsize = (256 * 1024); +dtrace_optval_t dtrace_dof_maxsize = (8 * 1024 * 1024); +size_t dtrace_statvar_maxsize = (16 * 1024); +size_t dtrace_actions_max = (16 * 1024); +size_t dtrace_retain_max = 1024; +dtrace_optval_t dtrace_helper_actions_max = 128; +dtrace_optval_t dtrace_helper_providers_max = 32; +dtrace_optval_t dtrace_dstate_defsize = (1 * 1024 * 1024); +size_t dtrace_strsize_default = 256; +dtrace_optval_t dtrace_cleanrate_default = 9900990; /* 101 hz */ +dtrace_optval_t dtrace_cleanrate_min = 200000; /* 5000 hz */ +dtrace_optval_t dtrace_cleanrate_max = (uint64_t)60 * NANOSEC; /* 1/minute */ +dtrace_optval_t dtrace_aggrate_default = NANOSEC; /* 1 hz */ +dtrace_optval_t dtrace_statusrate_default = NANOSEC; /* 1 hz */ +dtrace_optval_t dtrace_statusrate_max = (hrtime_t)10 * NANOSEC; /* 6/minute */ +dtrace_optval_t dtrace_switchrate_default = NANOSEC; /* 1 hz */ +dtrace_optval_t dtrace_nspec_default = 1; +dtrace_optval_t dtrace_specsize_default = 32 * 1024; +dtrace_optval_t dtrace_stackframes_default = 20; +dtrace_optval_t dtrace_ustackframes_default = 20; +dtrace_optval_t dtrace_jstackframes_default = 50; +dtrace_optval_t dtrace_jstackstrsize_default = 512; +int dtrace_msgdsize_max = 128; +hrtime_t dtrace_chill_max = MSEC2NSEC(500); /* 500 ms */ +hrtime_t dtrace_chill_interval = NANOSEC; /* 1000 ms */ +int dtrace_devdepth_max = 32; +int dtrace_err_verbose; +hrtime_t dtrace_deadman_interval = NANOSEC; +hrtime_t dtrace_deadman_timeout = (hrtime_t)10 * NANOSEC; +hrtime_t dtrace_deadman_user = (hrtime_t)30 * NANOSEC; +hrtime_t dtrace_unregister_defunct_reap = (hrtime_t)60 * NANOSEC; +#ifndef illumos +int dtrace_memstr_max = 4096; +#endif + +/* + * DTrace External Variables + * + * As dtrace(7D) is a kernel module, any DTrace variables are obviously + * available to DTrace consumers via the backtick (`) syntax. One of these, + * dtrace_zero, is made deliberately so: it is provided as a source of + * well-known, zero-filled memory. While this variable is not documented, + * it is used by some translators as an implementation detail. + */ +const char dtrace_zero[256] = { 0 }; /* zero-filled memory */ + +/* + * DTrace Internal Variables + */ +#ifdef illumos +static dev_info_t *dtrace_devi; /* device info */ +#endif +#ifdef illumos +static vmem_t *dtrace_arena; /* probe ID arena */ +static vmem_t *dtrace_minor; /* minor number arena */ +#else +static taskq_t *dtrace_taskq; /* task queue */ +static struct unrhdr *dtrace_arena; /* Probe ID number. */ +#endif +static dtrace_probe_t **dtrace_probes; /* array of all probes */ +static int dtrace_nprobes; /* number of probes */ +static dtrace_provider_t *dtrace_provider; /* provider list */ +static dtrace_meta_t *dtrace_meta_pid; /* user-land meta provider */ +static int dtrace_opens; /* number of opens */ +static int dtrace_helpers; /* number of helpers */ +static int dtrace_getf; /* number of unpriv getf()s */ +#ifdef illumos +static void *dtrace_softstate; /* softstate pointer */ +#endif +static dtrace_hash_t *dtrace_bymod; /* probes hashed by module */ +static dtrace_hash_t *dtrace_byfunc; /* probes hashed by function */ +static dtrace_hash_t *dtrace_byname; /* probes hashed by name */ +static dtrace_toxrange_t *dtrace_toxrange; /* toxic range array */ +static int dtrace_toxranges; /* number of toxic ranges */ +static int dtrace_toxranges_max; /* size of toxic range array */ +static dtrace_anon_t dtrace_anon; /* anonymous enabling */ +static kmem_cache_t *dtrace_state_cache; /* cache for dynamic state */ +static uint64_t dtrace_vtime_references; /* number of vtimestamp refs */ +static kthread_t *dtrace_panicked; /* panicking thread */ +static dtrace_ecb_t *dtrace_ecb_create_cache; /* cached created ECB */ +static dtrace_genid_t dtrace_probegen; /* current probe generation */ +static dtrace_helpers_t *dtrace_deferred_pid; /* deferred helper list */ +static dtrace_enabling_t *dtrace_retained; /* list of retained enablings */ +static dtrace_genid_t dtrace_retained_gen; /* current retained enab gen */ +static dtrace_dynvar_t dtrace_dynhash_sink; /* end of dynamic hash chains */ +static int dtrace_dynvar_failclean; /* dynvars failed to clean */ +#ifndef illumos +static struct mtx dtrace_unr_mtx; +MTX_SYSINIT(dtrace_unr_mtx, &dtrace_unr_mtx, "Unique resource identifier", MTX_DEF); +static eventhandler_tag dtrace_kld_load_tag; +static eventhandler_tag dtrace_kld_unload_try_tag; +#endif + +/* + * DTrace Locking + * DTrace is protected by three (relatively coarse-grained) locks: + * + * (1) dtrace_lock is required to manipulate essentially any DTrace state, + * including enabling state, probes, ECBs, consumer state, helper state, + * etc. Importantly, dtrace_lock is _not_ required when in probe context; + * probe context is lock-free -- synchronization is handled via the + * dtrace_sync() cross call mechanism. + * + * (2) dtrace_provider_lock is required when manipulating provider state, or + * when provider state must be held constant. + * + * (3) dtrace_meta_lock is required when manipulating meta provider state, or + * when meta provider state must be held constant. + * + * The lock ordering between these three locks is dtrace_meta_lock before + * dtrace_provider_lock before dtrace_lock. (In particular, there are + * several places where dtrace_provider_lock is held by the framework as it + * calls into the providers -- which then call back into the framework, + * grabbing dtrace_lock.) + * + * There are two other locks in the mix: mod_lock and cpu_lock. With respect + * to dtrace_provider_lock and dtrace_lock, cpu_lock continues its historical + * role as a coarse-grained lock; it is acquired before both of these locks. + * With respect to dtrace_meta_lock, its behavior is stranger: cpu_lock must + * be acquired _between_ dtrace_meta_lock and any other DTrace locks. + * mod_lock is similar with respect to dtrace_provider_lock in that it must be + * acquired _between_ dtrace_provider_lock and dtrace_lock. + */ +static kmutex_t dtrace_lock; /* probe state lock */ +static kmutex_t dtrace_provider_lock; /* provider state lock */ +static kmutex_t dtrace_meta_lock; /* meta-provider state lock */ + +#ifndef illumos +/* XXX FreeBSD hacks. */ +#define cr_suid cr_svuid +#define cr_sgid cr_svgid +#define ipaddr_t in_addr_t +#define mod_modname pathname +#define vuprintf vprintf +#ifndef crgetzoneid +#define crgetzoneid(_a) 0 +#endif +#define ttoproc(_a) ((_a)->td_proc) +#define SNOCD 0 +#define CPU_ON_INTR(_a) 0 + +#define PRIV_EFFECTIVE (1 << 0) +#define PRIV_DTRACE_KERNEL (1 << 1) +#define PRIV_DTRACE_PROC (1 << 2) +#define PRIV_DTRACE_USER (1 << 3) +#define PRIV_PROC_OWNER (1 << 4) +#define PRIV_PROC_ZONE (1 << 5) +#define PRIV_ALL ~0 + +SYSCTL_DECL(_debug_dtrace); +SYSCTL_DECL(_kern_dtrace); +#endif + +#ifdef illumos +#define curcpu CPU->cpu_id +#endif + + +/* + * DTrace Provider Variables + * + * These are the variables relating to DTrace as a provider (that is, the + * provider of the BEGIN, END, and ERROR probes). + */ +static dtrace_pattr_t dtrace_provider_attr = { +{ DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON }, +{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN }, +{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN }, +{ DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON }, +{ DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON }, +}; + +static void +dtrace_nullop(void) +{} + +static dtrace_pops_t dtrace_provider_ops = { + .dtps_provide = (void (*)(void *, dtrace_probedesc_t *))dtrace_nullop, + .dtps_provide_module = (void (*)(void *, modctl_t *))dtrace_nullop, + .dtps_enable = (void (*)(void *, dtrace_id_t, void *))dtrace_nullop, + .dtps_disable = (void (*)(void *, dtrace_id_t, void *))dtrace_nullop, + .dtps_suspend = (void (*)(void *, dtrace_id_t, void *))dtrace_nullop, + .dtps_resume = (void (*)(void *, dtrace_id_t, void *))dtrace_nullop, + .dtps_getargdesc = NULL, + .dtps_getargval = NULL, + .dtps_usermode = NULL, + .dtps_destroy = (void (*)(void *, dtrace_id_t, void *))dtrace_nullop, +}; + +static dtrace_id_t dtrace_probeid_begin; /* special BEGIN probe */ +static dtrace_id_t dtrace_probeid_end; /* special END probe */ +dtrace_id_t dtrace_probeid_error; /* special ERROR probe */ + +/* + * DTrace Helper Tracing Variables + * + * These variables should be set dynamically to enable helper tracing. The + * only variables that should be set are dtrace_helptrace_enable (which should + * be set to a non-zero value to allocate helper tracing buffers on the next + * open of /dev/dtrace) and dtrace_helptrace_disable (which should be set to a + * non-zero value to deallocate helper tracing buffers on the next close of + * /dev/dtrace). When (and only when) helper tracing is disabled, the + * buffer size may also be set via dtrace_helptrace_bufsize. + */ +int dtrace_helptrace_enable = 0; +int dtrace_helptrace_disable = 0; +int dtrace_helptrace_bufsize = 16 * 1024 * 1024; +uint32_t dtrace_helptrace_nlocals; +static dtrace_helptrace_t *dtrace_helptrace_buffer; +static uint32_t dtrace_helptrace_next = 0; +static int dtrace_helptrace_wrapped = 0; + +/* + * DTrace Error Hashing + * + * On DEBUG kernels, DTrace will track the errors that has seen in a hash + * table. This is very useful for checking coverage of tests that are + * expected to induce DIF or DOF processing errors, and may be useful for + * debugging problems in the DIF code generator or in DOF generation . The + * error hash may be examined with the ::dtrace_errhash MDB dcmd. + */ +#ifdef DEBUG +static dtrace_errhash_t dtrace_errhash[DTRACE_ERRHASHSZ]; +static const char *dtrace_errlast; +static kthread_t *dtrace_errthread; +static kmutex_t dtrace_errlock; +#endif + +/* + * DTrace Macros and Constants + * + * These are various macros that are useful in various spots in the + * implementation, along with a few random constants that have no meaning + * outside of the implementation. There is no real structure to this cpp + * mishmash -- but is there ever? + */ +#define DTRACE_HASHSTR(hash, probe) \ + dtrace_hash_str(*((char **)((uintptr_t)(probe) + (hash)->dth_stroffs))) + +#define DTRACE_HASHNEXT(hash, probe) \ + (dtrace_probe_t **)((uintptr_t)(probe) + (hash)->dth_nextoffs) + +#define DTRACE_HASHPREV(hash, probe) \ + (dtrace_probe_t **)((uintptr_t)(probe) + (hash)->dth_prevoffs) + +#define DTRACE_HASHEQ(hash, lhs, rhs) \ + (strcmp(*((char **)((uintptr_t)(lhs) + (hash)->dth_stroffs)), \ + *((char **)((uintptr_t)(rhs) + (hash)->dth_stroffs))) == 0) + +#define DTRACE_AGGHASHSIZE_SLEW 17 + +#define DTRACE_V4MAPPED_OFFSET (sizeof (uint32_t) * 3) + +/* + * The key for a thread-local variable consists of the lower 61 bits of the + * t_did, plus the 3 bits of the highest active interrupt above LOCK_LEVEL. + * We add DIF_VARIABLE_MAX to t_did to assure that the thread key is never + * equal to a variable identifier. This is necessary (but not sufficient) to + * assure that global associative arrays never collide with thread-local + * variables. To guarantee that they cannot collide, we must also define the + * order for keying dynamic variables. That order is: + * + * [ key0 ] ... [ keyn ] [ variable-key ] [ tls-key ] + * + * Because the variable-key and the tls-key are in orthogonal spaces, there is + * no way for a global variable key signature to match a thread-local key + * signature. + */ +#ifdef illumos +#define DTRACE_TLS_THRKEY(where) { \ + uint_t intr = 0; \ + uint_t actv = CPU->cpu_intr_actv >> (LOCK_LEVEL + 1); \ + for (; actv; actv >>= 1) \ + intr++; \ + ASSERT(intr < (1 << 3)); \ + (where) = ((curthread->t_did + DIF_VARIABLE_MAX) & \ + (((uint64_t)1 << 61) - 1)) | ((uint64_t)intr << 61); \ +} +#else +#define DTRACE_TLS_THRKEY(where) { \ + solaris_cpu_t *_c = &solaris_cpu[curcpu]; \ + uint_t intr = 0; \ + uint_t actv = _c->cpu_intr_actv; \ + for (; actv; actv >>= 1) \ + intr++; \ + ASSERT(intr < (1 << 3)); \ + (where) = ((curthread->td_tid + DIF_VARIABLE_MAX) & \ + (((uint64_t)1 << 61) - 1)) | ((uint64_t)intr << 61); \ +} +#endif + +#define DT_BSWAP_8(x) ((x) & 0xff) +#define DT_BSWAP_16(x) ((DT_BSWAP_8(x) << 8) | DT_BSWAP_8((x) >> 8)) +#define DT_BSWAP_32(x) ((DT_BSWAP_16(x) << 16) | DT_BSWAP_16((x) >> 16)) +#define DT_BSWAP_64(x) ((DT_BSWAP_32(x) << 32) | DT_BSWAP_32((x) >> 32)) + +#define DT_MASK_LO 0x00000000FFFFFFFFULL + +#define DTRACE_STORE(type, tomax, offset, what) \ + *((type *)((uintptr_t)(tomax) + (uintptr_t)offset)) = (type)(what); + +#ifndef __x86 +#define DTRACE_ALIGNCHECK(addr, size, flags) \ + if (addr & (size - 1)) { \ + *flags |= CPU_DTRACE_BADALIGN; \ + cpu_core[curcpu].cpuc_dtrace_illval = addr; \ + return (0); \ + } +#else +#define DTRACE_ALIGNCHECK(addr, size, flags) +#endif + +/* + * Test whether a range of memory starting at testaddr of size testsz falls + * within the range of memory described by addr, sz. We take care to avoid + * problems with overflow and underflow of the unsigned quantities, and + * disallow all negative sizes. Ranges of size 0 are allowed. + */ +#define DTRACE_INRANGE(testaddr, testsz, baseaddr, basesz) \ + ((testaddr) - (uintptr_t)(baseaddr) < (basesz) && \ + (testaddr) + (testsz) - (uintptr_t)(baseaddr) <= (basesz) && \ + (testaddr) + (testsz) >= (testaddr)) + +#define DTRACE_RANGE_REMAIN(remp, addr, baseaddr, basesz) \ +do { \ + if ((remp) != NULL) { \ + *(remp) = (uintptr_t)(baseaddr) + (basesz) - (addr); \ + } \ +} while (0) + + +/* + * Test whether alloc_sz bytes will fit in the scratch region. We isolate + * alloc_sz on the righthand side of the comparison in order to avoid overflow + * or underflow in the comparison with it. This is simpler than the INRANGE + * check above, because we know that the dtms_scratch_ptr is valid in the + * range. Allocations of size zero are allowed. + */ +#define DTRACE_INSCRATCH(mstate, alloc_sz) \ + ((mstate)->dtms_scratch_base + (mstate)->dtms_scratch_size - \ + (mstate)->dtms_scratch_ptr >= (alloc_sz)) + +#define DTRACE_LOADFUNC(bits) \ +/*CSTYLED*/ \ +uint##bits##_t \ +dtrace_load##bits(uintptr_t addr) \ +{ \ + size_t size = bits / NBBY; \ + /*CSTYLED*/ \ + uint##bits##_t rval; \ + int i; \ + volatile uint16_t *flags = (volatile uint16_t *) \ + &cpu_core[curcpu].cpuc_dtrace_flags; \ + \ + DTRACE_ALIGNCHECK(addr, size, flags); \ + \ + for (i = 0; i < dtrace_toxranges; i++) { \ + if (addr >= dtrace_toxrange[i].dtt_limit) \ + continue; \ + \ + if (addr + size <= dtrace_toxrange[i].dtt_base) \ + continue; \ + \ + /* \ + * This address falls within a toxic region; return 0. \ + */ \ + *flags |= CPU_DTRACE_BADADDR; \ + cpu_core[curcpu].cpuc_dtrace_illval = addr; \ + return (0); \ + } \ + \ + *flags |= CPU_DTRACE_NOFAULT; \ + /*CSTYLED*/ \ + rval = *((volatile uint##bits##_t *)addr); \ + *flags &= ~CPU_DTRACE_NOFAULT; \ + \ + return (!(*flags & CPU_DTRACE_FAULT) ? rval : 0); \ +} + +#ifdef _LP64 +#define dtrace_loadptr dtrace_load64 +#else +#define dtrace_loadptr dtrace_load32 +#endif + +#define DTRACE_DYNHASH_FREE 0 +#define DTRACE_DYNHASH_SINK 1 +#define DTRACE_DYNHASH_VALID 2 + +#define DTRACE_MATCH_NEXT 0 +#define DTRACE_MATCH_DONE 1 +#define DTRACE_ANCHORED(probe) ((probe)->dtpr_func[0] != '\0') +#define DTRACE_STATE_ALIGN 64 + +#define DTRACE_FLAGS2FLT(flags) \ + (((flags) & CPU_DTRACE_BADADDR) ? DTRACEFLT_BADADDR : \ + ((flags) & CPU_DTRACE_ILLOP) ? DTRACEFLT_ILLOP : \ + ((flags) & CPU_DTRACE_DIVZERO) ? DTRACEFLT_DIVZERO : \ + ((flags) & CPU_DTRACE_KPRIV) ? DTRACEFLT_KPRIV : \ + ((flags) & CPU_DTRACE_UPRIV) ? DTRACEFLT_UPRIV : \ + ((flags) & CPU_DTRACE_TUPOFLOW) ? DTRACEFLT_TUPOFLOW : \ + ((flags) & CPU_DTRACE_BADALIGN) ? DTRACEFLT_BADALIGN : \ + ((flags) & CPU_DTRACE_NOSCRATCH) ? DTRACEFLT_NOSCRATCH : \ + ((flags) & CPU_DTRACE_BADSTACK) ? DTRACEFLT_BADSTACK : \ + DTRACEFLT_UNKNOWN) + +#define DTRACEACT_ISSTRING(act) \ + ((act)->dta_kind == DTRACEACT_DIFEXPR && \ + (act)->dta_difo->dtdo_rtype.dtdt_kind == DIF_TYPE_STRING) + +/* Function prototype definitions: */ +static size_t dtrace_strlen(const char *, size_t); +static dtrace_probe_t *dtrace_probe_lookup_id(dtrace_id_t id); +static void dtrace_enabling_provide(dtrace_provider_t *); +static int dtrace_enabling_match(dtrace_enabling_t *, int *); +static void dtrace_enabling_matchall(void); +static void dtrace_enabling_reap(void); +static dtrace_state_t *dtrace_anon_grab(void); +static uint64_t dtrace_helper(int, dtrace_mstate_t *, + dtrace_state_t *, uint64_t, uint64_t); +static dtrace_helpers_t *dtrace_helpers_create(proc_t *); +static void dtrace_buffer_drop(dtrace_buffer_t *); +static int dtrace_buffer_consumed(dtrace_buffer_t *, hrtime_t when); +static intptr_t dtrace_buffer_reserve(dtrace_buffer_t *, size_t, size_t, + dtrace_state_t *, dtrace_mstate_t *); +static int dtrace_state_option(dtrace_state_t *, dtrace_optid_t, + dtrace_optval_t); +static int dtrace_ecb_create_enable(dtrace_probe_t *, void *); +static void dtrace_helper_provider_destroy(dtrace_helper_provider_t *); +uint16_t dtrace_load16(uintptr_t); +uint32_t dtrace_load32(uintptr_t); +uint64_t dtrace_load64(uintptr_t); +uint8_t dtrace_load8(uintptr_t); +void dtrace_dynvar_clean(dtrace_dstate_t *); +dtrace_dynvar_t *dtrace_dynvar(dtrace_dstate_t *, uint_t, dtrace_key_t *, + size_t, dtrace_dynvar_op_t, dtrace_mstate_t *, dtrace_vstate_t *); +uintptr_t dtrace_dif_varstr(uintptr_t, dtrace_state_t *, dtrace_mstate_t *); +static int dtrace_priv_proc(dtrace_state_t *); +static void dtrace_getf_barrier(void); +static int dtrace_canload_remains(uint64_t, size_t, size_t *, + dtrace_mstate_t *, dtrace_vstate_t *); +static int dtrace_canstore_remains(uint64_t, size_t, size_t *, + dtrace_mstate_t *, dtrace_vstate_t *); + +/* + * DTrace Probe Context Functions + * + * These functions are called from probe context. Because probe context is + * any context in which C may be called, arbitrarily locks may be held, + * interrupts may be disabled, we may be in arbitrary dispatched state, etc. + * As a result, functions called from probe context may only call other DTrace + * support functions -- they may not interact at all with the system at large. + * (Note that the ASSERT macro is made probe-context safe by redefining it in + * terms of dtrace_assfail(), a probe-context safe function.) If arbitrary + * loads are to be performed from probe context, they _must_ be in terms of + * the safe dtrace_load*() variants. + * + * Some functions in this block are not actually called from probe context; + * for these functions, there will be a comment above the function reading + * "Note: not called from probe context." + */ +void +dtrace_panic(const char *format, ...) +{ + va_list alist; + + va_start(alist, format); +#ifdef __FreeBSD__ + vpanic(format, alist); +#else + dtrace_vpanic(format, alist); +#endif + va_end(alist); +} + +int +dtrace_assfail(const char *a, const char *f, int l) +{ + dtrace_panic("assertion failed: %s, file: %s, line: %d", a, f, l); + + /* + * We just need something here that even the most clever compiler + * cannot optimize away. + */ + return (a[(uintptr_t)f]); +} + +/* + * Atomically increment a specified error counter from probe context. + */ +static void +dtrace_error(uint32_t *counter) +{ + /* + * Most counters stored to in probe context are per-CPU counters. + * However, there are some error conditions that are sufficiently + * arcane that they don't merit per-CPU storage. If these counters + * are incremented concurrently on different CPUs, scalability will be + * adversely affected -- but we don't expect them to be white-hot in a + * correctly constructed enabling... + */ + uint32_t oval, nval; + + do { + oval = *counter; + + if ((nval = oval + 1) == 0) { + /* + * If the counter would wrap, set it to 1 -- assuring + * that the counter is never zero when we have seen + * errors. (The counter must be 32-bits because we + * aren't guaranteed a 64-bit compare&swap operation.) + * To save this code both the infamy of being fingered + * by a priggish news story and the indignity of being + * the target of a neo-puritan witch trial, we're + * carefully avoiding any colorful description of the + * likelihood of this condition -- but suffice it to + * say that it is only slightly more likely than the + * overflow of predicate cache IDs, as discussed in + * dtrace_predicate_create(). + */ + nval = 1; + } + } while (dtrace_cas32(counter, oval, nval) != oval); +} + +/* + * Use the DTRACE_LOADFUNC macro to define functions for each of loading a + * uint8_t, a uint16_t, a uint32_t and a uint64_t. + */ +/* BEGIN CSTYLED */ +DTRACE_LOADFUNC(8) +DTRACE_LOADFUNC(16) +DTRACE_LOADFUNC(32) +DTRACE_LOADFUNC(64) +/* END CSTYLED */ + +static int +dtrace_inscratch(uintptr_t dest, size_t size, dtrace_mstate_t *mstate) +{ + if (dest < mstate->dtms_scratch_base) + return (0); + + if (dest + size < dest) + return (0); + + if (dest + size > mstate->dtms_scratch_ptr) + return (0); + + return (1); +} + +static int +dtrace_canstore_statvar(uint64_t addr, size_t sz, size_t *remain, + dtrace_statvar_t **svars, int nsvars) +{ + int i; + size_t maxglobalsize, maxlocalsize; + + if (nsvars == 0) + return (0); + + maxglobalsize = dtrace_statvar_maxsize + sizeof (uint64_t); + maxlocalsize = maxglobalsize * NCPU; + + for (i = 0; i < nsvars; i++) { + dtrace_statvar_t *svar = svars[i]; + uint8_t scope; + size_t size; + + if (svar == NULL || (size = svar->dtsv_size) == 0) + continue; + + scope = svar->dtsv_var.dtdv_scope; + + /* + * We verify that our size is valid in the spirit of providing + * defense in depth: we want to prevent attackers from using + * DTrace to escalate an orthogonal kernel heap corruption bug + * into the ability to store to arbitrary locations in memory. + */ + VERIFY((scope == DIFV_SCOPE_GLOBAL && size <= maxglobalsize) || + (scope == DIFV_SCOPE_LOCAL && size <= maxlocalsize)); + + if (DTRACE_INRANGE(addr, sz, svar->dtsv_data, + svar->dtsv_size)) { + DTRACE_RANGE_REMAIN(remain, addr, svar->dtsv_data, + svar->dtsv_size); + return (1); + } + } + + return (0); +} + +/* + * Check to see if the address is within a memory region to which a store may + * be issued. This includes the DTrace scratch areas, and any DTrace variable + * region. The caller of dtrace_canstore() is responsible for performing any + * alignment checks that are needed before stores are actually executed. + */ +static int +dtrace_canstore(uint64_t addr, size_t sz, dtrace_mstate_t *mstate, + dtrace_vstate_t *vstate) +{ + return (dtrace_canstore_remains(addr, sz, NULL, mstate, vstate)); +} + +/* + * Implementation of dtrace_canstore which communicates the upper bound of the + * allowed memory region. + */ +static int +dtrace_canstore_remains(uint64_t addr, size_t sz, size_t *remain, + dtrace_mstate_t *mstate, dtrace_vstate_t *vstate) +{ + /* + * First, check to see if the address is in scratch space... + */ + if (DTRACE_INRANGE(addr, sz, mstate->dtms_scratch_base, + mstate->dtms_scratch_size)) { + DTRACE_RANGE_REMAIN(remain, addr, mstate->dtms_scratch_base, + mstate->dtms_scratch_size); + return (1); + } + + /* + * Now check to see if it's a dynamic variable. This check will pick + * up both thread-local variables and any global dynamically-allocated + * variables. + */ + if (DTRACE_INRANGE(addr, sz, vstate->dtvs_dynvars.dtds_base, + vstate->dtvs_dynvars.dtds_size)) { + dtrace_dstate_t *dstate = &vstate->dtvs_dynvars; + uintptr_t base = (uintptr_t)dstate->dtds_base + + (dstate->dtds_hashsize * sizeof (dtrace_dynhash_t)); + uintptr_t chunkoffs; + dtrace_dynvar_t *dvar; + + /* + * Before we assume that we can store here, we need to make + * sure that it isn't in our metadata -- storing to our + * dynamic variable metadata would corrupt our state. For + * the range to not include any dynamic variable metadata, + * it must: + * + * (1) Start above the hash table that is at the base of + * the dynamic variable space + * + * (2) Have a starting chunk offset that is beyond the + * dtrace_dynvar_t that is at the base of every chunk + * + * (3) Not span a chunk boundary + * + * (4) Not be in the tuple space of a dynamic variable + * + */ + if (addr < base) + return (0); + + chunkoffs = (addr - base) % dstate->dtds_chunksize; + + if (chunkoffs < sizeof (dtrace_dynvar_t)) + return (0); + + if (chunkoffs + sz > dstate->dtds_chunksize) + return (0); + + dvar = (dtrace_dynvar_t *)((uintptr_t)addr - chunkoffs); + + if (dvar->dtdv_hashval == DTRACE_DYNHASH_FREE) + return (0); + + if (chunkoffs < sizeof (dtrace_dynvar_t) + + ((dvar->dtdv_tuple.dtt_nkeys - 1) * sizeof (dtrace_key_t))) + return (0); + + DTRACE_RANGE_REMAIN(remain, addr, dvar, dstate->dtds_chunksize); + return (1); + } + + /* + * Finally, check the static local and global variables. These checks + * take the longest, so we perform them last. + */ + if (dtrace_canstore_statvar(addr, sz, remain, + vstate->dtvs_locals, vstate->dtvs_nlocals)) + return (1); + + if (dtrace_canstore_statvar(addr, sz, remain, + vstate->dtvs_globals, vstate->dtvs_nglobals)) + return (1); + + return (0); +} + + +/* + * Convenience routine to check to see if the address is within a memory + * region in which a load may be issued given the user's privilege level; + * if not, it sets the appropriate error flags and loads 'addr' into the + * illegal value slot. + * + * DTrace subroutines (DIF_SUBR_*) should use this helper to implement + * appropriate memory access protection. + */ +static int +dtrace_canload(uint64_t addr, size_t sz, dtrace_mstate_t *mstate, + dtrace_vstate_t *vstate) +{ + return (dtrace_canload_remains(addr, sz, NULL, mstate, vstate)); +} + +/* + * Implementation of dtrace_canload which communicates the uppoer bound of the + * allowed memory region. + */ +static int +dtrace_canload_remains(uint64_t addr, size_t sz, size_t *remain, + dtrace_mstate_t *mstate, dtrace_vstate_t *vstate) +{ + volatile uintptr_t *illval = &cpu_core[curcpu].cpuc_dtrace_illval; + file_t *fp; + + /* + * If we hold the privilege to read from kernel memory, then + * everything is readable. + */ + if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0) { + DTRACE_RANGE_REMAIN(remain, addr, addr, sz); + return (1); + } + + /* + * You can obviously read that which you can store. + */ + if (dtrace_canstore_remains(addr, sz, remain, mstate, vstate)) + return (1); + + /* + * We're allowed to read from our own string table. + */ + if (DTRACE_INRANGE(addr, sz, mstate->dtms_difo->dtdo_strtab, + mstate->dtms_difo->dtdo_strlen)) { + DTRACE_RANGE_REMAIN(remain, addr, + mstate->dtms_difo->dtdo_strtab, + mstate->dtms_difo->dtdo_strlen); + return (1); + } + + if (vstate->dtvs_state != NULL && + dtrace_priv_proc(vstate->dtvs_state)) { + proc_t *p; + + /* + * When we have privileges to the current process, there are + * several context-related kernel structures that are safe to + * read, even absent the privilege to read from kernel memory. + * These reads are safe because these structures contain only + * state that (1) we're permitted to read, (2) is harmless or + * (3) contains pointers to additional kernel state that we're + * not permitted to read (and as such, do not present an + * opportunity for privilege escalation). Finally (and + * critically), because of the nature of their relation with + * the current thread context, the memory associated with these + * structures cannot change over the duration of probe context, + * and it is therefore impossible for this memory to be + * deallocated and reallocated as something else while it's + * being operated upon. + */ + if (DTRACE_INRANGE(addr, sz, curthread, sizeof (kthread_t))) { + DTRACE_RANGE_REMAIN(remain, addr, curthread, + sizeof (kthread_t)); + return (1); + } + + if ((p = curthread->t_procp) != NULL && DTRACE_INRANGE(addr, + sz, curthread->t_procp, sizeof (proc_t))) { + DTRACE_RANGE_REMAIN(remain, addr, curthread->t_procp, + sizeof (proc_t)); + return (1); + } + + if (curthread->t_cred != NULL && DTRACE_INRANGE(addr, sz, + curthread->t_cred, sizeof (cred_t))) { + DTRACE_RANGE_REMAIN(remain, addr, curthread->t_cred, + sizeof (cred_t)); + return (1); + } + +#ifdef illumos + if (p != NULL && p->p_pidp != NULL && DTRACE_INRANGE(addr, sz, + &(p->p_pidp->pid_id), sizeof (pid_t))) { + DTRACE_RANGE_REMAIN(remain, addr, &(p->p_pidp->pid_id), + sizeof (pid_t)); + return (1); + } + + if (curthread->t_cpu != NULL && DTRACE_INRANGE(addr, sz, + curthread->t_cpu, offsetof(cpu_t, cpu_pause_thread))) { + DTRACE_RANGE_REMAIN(remain, addr, curthread->t_cpu, + offsetof(cpu_t, cpu_pause_thread)); + return (1); + } +#endif + } + + if ((fp = mstate->dtms_getf) != NULL) { + uintptr_t psz = sizeof (void *); + vnode_t *vp; + vnodeops_t *op; + + /* + * When getf() returns a file_t, the enabling is implicitly + * granted the (transient) right to read the returned file_t + * as well as the v_path and v_op->vnop_name of the underlying + * vnode. These accesses are allowed after a successful + * getf() because the members that they refer to cannot change + * once set -- and the barrier logic in the kernel's closef() + * path assures that the file_t and its referenced vode_t + * cannot themselves be stale (that is, it impossible for + * either dtms_getf itself or its f_vnode member to reference + * freed memory). + */ + if (DTRACE_INRANGE(addr, sz, fp, sizeof (file_t))) { + DTRACE_RANGE_REMAIN(remain, addr, fp, sizeof (file_t)); + return (1); + } + + if ((vp = fp->f_vnode) != NULL) { + size_t slen; +#ifdef illumos + if (DTRACE_INRANGE(addr, sz, &vp->v_path, psz)) { + DTRACE_RANGE_REMAIN(remain, addr, &vp->v_path, + psz); + return (1); + } + slen = strlen(vp->v_path) + 1; + if (DTRACE_INRANGE(addr, sz, vp->v_path, slen)) { + DTRACE_RANGE_REMAIN(remain, addr, vp->v_path, + slen); + return (1); + } +#endif + + if (DTRACE_INRANGE(addr, sz, &vp->v_op, psz)) { + DTRACE_RANGE_REMAIN(remain, addr, &vp->v_op, + psz); + return (1); + } + +#ifdef illumos + if ((op = vp->v_op) != NULL && + DTRACE_INRANGE(addr, sz, &op->vnop_name, psz)) { + DTRACE_RANGE_REMAIN(remain, addr, + &op->vnop_name, psz); + return (1); + } + + if (op != NULL && op->vnop_name != NULL && + DTRACE_INRANGE(addr, sz, op->vnop_name, + (slen = strlen(op->vnop_name) + 1))) { + DTRACE_RANGE_REMAIN(remain, addr, + op->vnop_name, slen); + return (1); + } +#endif + } + } + + DTRACE_CPUFLAG_SET(CPU_DTRACE_KPRIV); + *illval = addr; + return (0); +} + +/* + * Convenience routine to check to see if a given string is within a memory + * region in which a load may be issued given the user's privilege level; + * this exists so that we don't need to issue unnecessary dtrace_strlen() + * calls in the event that the user has all privileges. + */ +static int +dtrace_strcanload(uint64_t addr, size_t sz, size_t *remain, + dtrace_mstate_t *mstate, dtrace_vstate_t *vstate) +{ + size_t rsize; + + /* + * If we hold the privilege to read from kernel memory, then + * everything is readable. + */ + if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0) { + DTRACE_RANGE_REMAIN(remain, addr, addr, sz); + return (1); + } + + /* + * Even if the caller is uninterested in querying the remaining valid + * range, it is required to ensure that the access is allowed. + */ + if (remain == NULL) { + remain = &rsize; + } + if (dtrace_canload_remains(addr, 0, remain, mstate, vstate)) { + size_t strsz; + /* + * Perform the strlen after determining the length of the + * memory region which is accessible. This prevents timing + * information from being used to find NULs in memory which is + * not accessible to the caller. + */ + strsz = 1 + dtrace_strlen((char *)(uintptr_t)addr, + MIN(sz, *remain)); + if (strsz <= *remain) { + return (1); + } + } + + return (0); +} + +/* + * Convenience routine to check to see if a given variable is within a memory + * region in which a load may be issued given the user's privilege level. + */ +static int +dtrace_vcanload(void *src, dtrace_diftype_t *type, size_t *remain, + dtrace_mstate_t *mstate, dtrace_vstate_t *vstate) +{ + size_t sz; + ASSERT(type->dtdt_flags & DIF_TF_BYREF); + + /* + * Calculate the max size before performing any checks since even + * DTRACE_ACCESS_KERNEL-credentialed callers expect that this function + * return the max length via 'remain'. + */ + if (type->dtdt_kind == DIF_TYPE_STRING) { + dtrace_state_t *state = vstate->dtvs_state; + + if (state != NULL) { + sz = state->dts_options[DTRACEOPT_STRSIZE]; + } else { + /* + * In helper context, we have a NULL state; fall back + * to using the system-wide default for the string size + * in this case. + */ + sz = dtrace_strsize_default; + } + } else { + sz = type->dtdt_size; + } + + /* + * If we hold the privilege to read from kernel memory, then + * everything is readable. + */ + if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0) { + DTRACE_RANGE_REMAIN(remain, (uintptr_t)src, src, sz); + return (1); + } + + if (type->dtdt_kind == DIF_TYPE_STRING) { + return (dtrace_strcanload((uintptr_t)src, sz, remain, mstate, + vstate)); + } + return (dtrace_canload_remains((uintptr_t)src, sz, remain, mstate, + vstate)); +} + +/* + * Convert a string to a signed integer using safe loads. + * + * NOTE: This function uses various macros from strtolctype.h to manipulate + * digit values, etc -- these have all been checked to ensure they make + * no additional function calls. + */ +static int64_t +dtrace_strtoll(char *input, int base, size_t limit) +{ + uintptr_t pos = (uintptr_t)input; + int64_t val = 0; + int x; + boolean_t neg = B_FALSE; + char c, cc, ccc; + uintptr_t end = pos + limit; + + /* + * Consume any whitespace preceding digits. + */ + while ((c = dtrace_load8(pos)) == ' ' || c == '\t') + pos++; + + /* + * Handle an explicit sign if one is present. + */ + if (c == '-' || c == '+') { + if (c == '-') + neg = B_TRUE; + c = dtrace_load8(++pos); + } + + /* + * Check for an explicit hexadecimal prefix ("0x" or "0X") and skip it + * if present. + */ + if (base == 16 && c == '0' && ((cc = dtrace_load8(pos + 1)) == 'x' || + cc == 'X') && isxdigit(ccc = dtrace_load8(pos + 2))) { + pos += 2; + c = ccc; + } + + /* + * Read in contiguous digits until the first non-digit character. + */ + for (; pos < end && c != '\0' && lisalnum(c) && (x = DIGIT(c)) < base; + c = dtrace_load8(++pos)) + val = val * base + x; + + return (neg ? -val : val); +} + +/* + * Compare two strings using safe loads. + */ +static int +dtrace_strncmp(char *s1, char *s2, size_t limit) +{ + uint8_t c1, c2; + volatile uint16_t *flags; + + if (s1 == s2 || limit == 0) + return (0); + + flags = (volatile uint16_t *)&cpu_core[curcpu].cpuc_dtrace_flags; + + do { + if (s1 == NULL) { + c1 = '\0'; + } else { + c1 = dtrace_load8((uintptr_t)s1++); + } + + if (s2 == NULL) { + c2 = '\0'; + } else { + c2 = dtrace_load8((uintptr_t)s2++); + } + + if (c1 != c2) + return (c1 - c2); + } while (--limit && c1 != '\0' && !(*flags & CPU_DTRACE_FAULT)); + + return (0); +} + +/* + * Compute strlen(s) for a string using safe memory accesses. The additional + * len parameter is used to specify a maximum length to ensure completion. + */ +static size_t +dtrace_strlen(const char *s, size_t lim) +{ + uint_t len; + + for (len = 0; len != lim; len++) { + if (dtrace_load8((uintptr_t)s++) == '\0') + break; + } + + return (len); +} + +/* + * Check if an address falls within a toxic region. + */ +static int +dtrace_istoxic(uintptr_t kaddr, size_t size) +{ + uintptr_t taddr, tsize; + int i; + + for (i = 0; i < dtrace_toxranges; i++) { + taddr = dtrace_toxrange[i].dtt_base; + tsize = dtrace_toxrange[i].dtt_limit - taddr; + + if (kaddr - taddr < tsize) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); + cpu_core[curcpu].cpuc_dtrace_illval = kaddr; + return (1); + } + + if (taddr - kaddr < size) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); + cpu_core[curcpu].cpuc_dtrace_illval = taddr; + return (1); + } + } + + return (0); +} + +/* + * Copy src to dst using safe memory accesses. The src is assumed to be unsafe + * memory specified by the DIF program. The dst is assumed to be safe memory + * that we can store to directly because it is managed by DTrace. As with + * standard bcopy, overlapping copies are handled properly. + */ +static void +dtrace_bcopy(const void *src, void *dst, size_t len) +{ + if (len != 0) { + uint8_t *s1 = dst; + const uint8_t *s2 = src; + + if (s1 <= s2) { + do { + *s1++ = dtrace_load8((uintptr_t)s2++); + } while (--len != 0); + } else { + s2 += len; + s1 += len; + + do { + *--s1 = dtrace_load8((uintptr_t)--s2); + } while (--len != 0); + } + } +} + +/* + * Copy src to dst using safe memory accesses, up to either the specified + * length, or the point that a nul byte is encountered. The src is assumed to + * be unsafe memory specified by the DIF program. The dst is assumed to be + * safe memory that we can store to directly because it is managed by DTrace. + * Unlike dtrace_bcopy(), overlapping regions are not handled. + */ +static void +dtrace_strcpy(const void *src, void *dst, size_t len) +{ + if (len != 0) { + uint8_t *s1 = dst, c; + const uint8_t *s2 = src; + + do { + *s1++ = c = dtrace_load8((uintptr_t)s2++); + } while (--len != 0 && c != '\0'); + } +} + +/* + * Copy src to dst, deriving the size and type from the specified (BYREF) + * variable type. The src is assumed to be unsafe memory specified by the DIF + * program. The dst is assumed to be DTrace variable memory that is of the + * specified type; we assume that we can store to directly. + */ +static void +dtrace_vcopy(void *src, void *dst, dtrace_diftype_t *type, size_t limit) +{ + ASSERT(type->dtdt_flags & DIF_TF_BYREF); + + if (type->dtdt_kind == DIF_TYPE_STRING) { + dtrace_strcpy(src, dst, MIN(type->dtdt_size, limit)); + } else { + dtrace_bcopy(src, dst, MIN(type->dtdt_size, limit)); + } +} + +/* + * Compare s1 to s2 using safe memory accesses. The s1 data is assumed to be + * unsafe memory specified by the DIF program. The s2 data is assumed to be + * safe memory that we can access directly because it is managed by DTrace. + */ +static int +dtrace_bcmp(const void *s1, const void *s2, size_t len) +{ + volatile uint16_t *flags; + + flags = (volatile uint16_t *)&cpu_core[curcpu].cpuc_dtrace_flags; + + if (s1 == s2) + return (0); + + if (s1 == NULL || s2 == NULL) + return (1); + + if (s1 != s2 && len != 0) { + const uint8_t *ps1 = s1; + const uint8_t *ps2 = s2; + + do { + if (dtrace_load8((uintptr_t)ps1++) != *ps2++) + return (1); + } while (--len != 0 && !(*flags & CPU_DTRACE_FAULT)); + } + return (0); +} + +/* + * Zero the specified region using a simple byte-by-byte loop. Note that this + * is for safe DTrace-managed memory only. + */ +static void +dtrace_bzero(void *dst, size_t len) +{ + uchar_t *cp; + + for (cp = dst; len != 0; len--) + *cp++ = 0; +} + +static void +dtrace_add_128(uint64_t *addend1, uint64_t *addend2, uint64_t *sum) +{ + uint64_t result[2]; + + result[0] = addend1[0] + addend2[0]; + result[1] = addend1[1] + addend2[1] + + (result[0] < addend1[0] || result[0] < addend2[0] ? 1 : 0); + + sum[0] = result[0]; + sum[1] = result[1]; +} + +/* + * Shift the 128-bit value in a by b. If b is positive, shift left. + * If b is negative, shift right. + */ +static void +dtrace_shift_128(uint64_t *a, int b) +{ + uint64_t mask; + + if (b == 0) + return; + + if (b < 0) { + b = -b; + if (b >= 64) { + a[0] = a[1] >> (b - 64); + a[1] = 0; + } else { + a[0] >>= b; + mask = 1LL << (64 - b); + mask -= 1; + a[0] |= ((a[1] & mask) << (64 - b)); + a[1] >>= b; + } + } else { + if (b >= 64) { + a[1] = a[0] << (b - 64); + a[0] = 0; + } else { + a[1] <<= b; + mask = a[0] >> (64 - b); + a[1] |= mask; + a[0] <<= b; + } + } +} + +/* + * The basic idea is to break the 2 64-bit values into 4 32-bit values, + * use native multiplication on those, and then re-combine into the + * resulting 128-bit value. + * + * (hi1 << 32 + lo1) * (hi2 << 32 + lo2) = + * hi1 * hi2 << 64 + + * hi1 * lo2 << 32 + + * hi2 * lo1 << 32 + + * lo1 * lo2 + */ +static void +dtrace_multiply_128(uint64_t factor1, uint64_t factor2, uint64_t *product) +{ + uint64_t hi1, hi2, lo1, lo2; + uint64_t tmp[2]; + + hi1 = factor1 >> 32; + hi2 = factor2 >> 32; + + lo1 = factor1 & DT_MASK_LO; + lo2 = factor2 & DT_MASK_LO; + + product[0] = lo1 * lo2; + product[1] = hi1 * hi2; + + tmp[0] = hi1 * lo2; + tmp[1] = 0; + dtrace_shift_128(tmp, 32); + dtrace_add_128(product, tmp, product); + + tmp[0] = hi2 * lo1; + tmp[1] = 0; + dtrace_shift_128(tmp, 32); + dtrace_add_128(product, tmp, product); +} + +/* + * This privilege check should be used by actions and subroutines to + * verify that the user credentials of the process that enabled the + * invoking ECB match the target credentials + */ +static int +dtrace_priv_proc_common_user(dtrace_state_t *state) +{ + cred_t *cr, *s_cr = state->dts_cred.dcr_cred; + + /* + * We should always have a non-NULL state cred here, since if cred + * is null (anonymous tracing), we fast-path bypass this routine. + */ + ASSERT(s_cr != NULL); + + if ((cr = CRED()) != NULL && + s_cr->cr_uid == cr->cr_uid && + s_cr->cr_uid == cr->cr_ruid && + s_cr->cr_uid == cr->cr_suid && + s_cr->cr_gid == cr->cr_gid && + s_cr->cr_gid == cr->cr_rgid && + s_cr->cr_gid == cr->cr_sgid) + return (1); + + return (0); +} + +/* + * This privilege check should be used by actions and subroutines to + * verify that the zone of the process that enabled the invoking ECB + * matches the target credentials + */ +static int +dtrace_priv_proc_common_zone(dtrace_state_t *state) +{ +#ifdef illumos + cred_t *cr, *s_cr = state->dts_cred.dcr_cred; + + /* + * We should always have a non-NULL state cred here, since if cred + * is null (anonymous tracing), we fast-path bypass this routine. + */ + ASSERT(s_cr != NULL); + + if ((cr = CRED()) != NULL && s_cr->cr_zone == cr->cr_zone) + return (1); + + return (0); +#else + return (1); +#endif +} + +/* + * This privilege check should be used by actions and subroutines to + * verify that the process has not setuid or changed credentials. + */ +static int +dtrace_priv_proc_common_nocd(void) +{ + proc_t *proc; + + if ((proc = ttoproc(curthread)) != NULL && + !(proc->p_flag & SNOCD)) + return (1); + + return (0); +} + +static int +dtrace_priv_proc_destructive(dtrace_state_t *state) +{ + int action = state->dts_cred.dcr_action; + + if (((action & DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE) == 0) && + dtrace_priv_proc_common_zone(state) == 0) + goto bad; + + if (((action & DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER) == 0) && + dtrace_priv_proc_common_user(state) == 0) + goto bad; + + if (((action & DTRACE_CRA_PROC_DESTRUCTIVE_CREDCHG) == 0) && + dtrace_priv_proc_common_nocd() == 0) + goto bad; + + return (1); + +bad: + cpu_core[curcpu].cpuc_dtrace_flags |= CPU_DTRACE_UPRIV; + + return (0); +} + +static int +dtrace_priv_proc_control(dtrace_state_t *state) +{ + if (state->dts_cred.dcr_action & DTRACE_CRA_PROC_CONTROL) + return (1); + + if (dtrace_priv_proc_common_zone(state) && + dtrace_priv_proc_common_user(state) && + dtrace_priv_proc_common_nocd()) + return (1); + + cpu_core[curcpu].cpuc_dtrace_flags |= CPU_DTRACE_UPRIV; + + return (0); +} + +static int +dtrace_priv_proc(dtrace_state_t *state) +{ + if (state->dts_cred.dcr_action & DTRACE_CRA_PROC) + return (1); + + cpu_core[curcpu].cpuc_dtrace_flags |= CPU_DTRACE_UPRIV; + + return (0); +} + +static int +dtrace_priv_kernel(dtrace_state_t *state) +{ + if (state->dts_cred.dcr_action & DTRACE_CRA_KERNEL) + return (1); + + cpu_core[curcpu].cpuc_dtrace_flags |= CPU_DTRACE_KPRIV; + + return (0); +} + +static int +dtrace_priv_kernel_destructive(dtrace_state_t *state) +{ + if (state->dts_cred.dcr_action & DTRACE_CRA_KERNEL_DESTRUCTIVE) + return (1); + + cpu_core[curcpu].cpuc_dtrace_flags |= CPU_DTRACE_KPRIV; + + return (0); +} + +/* + * Determine if the dte_cond of the specified ECB allows for processing of + * the current probe to continue. Note that this routine may allow continued + * processing, but with access(es) stripped from the mstate's dtms_access + * field. + */ +static int +dtrace_priv_probe(dtrace_state_t *state, dtrace_mstate_t *mstate, + dtrace_ecb_t *ecb) +{ + dtrace_probe_t *probe = ecb->dte_probe; + dtrace_provider_t *prov = probe->dtpr_provider; + dtrace_pops_t *pops = &prov->dtpv_pops; + int mode = DTRACE_MODE_NOPRIV_DROP; + + ASSERT(ecb->dte_cond); + +#ifdef illumos + if (pops->dtps_mode != NULL) { + mode = pops->dtps_mode(prov->dtpv_arg, + probe->dtpr_id, probe->dtpr_arg); + + ASSERT((mode & DTRACE_MODE_USER) || + (mode & DTRACE_MODE_KERNEL)); + ASSERT((mode & DTRACE_MODE_NOPRIV_RESTRICT) || + (mode & DTRACE_MODE_NOPRIV_DROP)); + } + + /* + * If the dte_cond bits indicate that this consumer is only allowed to + * see user-mode firings of this probe, call the provider's dtps_mode() + * entry point to check that the probe was fired while in a user + * context. If that's not the case, use the policy specified by the + * provider to determine if we drop the probe or merely restrict + * operation. + */ + if (ecb->dte_cond & DTRACE_COND_USERMODE) { + ASSERT(mode != DTRACE_MODE_NOPRIV_DROP); + + if (!(mode & DTRACE_MODE_USER)) { + if (mode & DTRACE_MODE_NOPRIV_DROP) + return (0); + + mstate->dtms_access &= ~DTRACE_ACCESS_ARGS; + } + } +#endif + + /* + * This is more subtle than it looks. We have to be absolutely certain + * that CRED() isn't going to change out from under us so it's only + * legit to examine that structure if we're in constrained situations. + * Currently, the only times we'll this check is if a non-super-user + * has enabled the profile or syscall providers -- providers that + * allow visibility of all processes. For the profile case, the check + * above will ensure that we're examining a user context. + */ + if (ecb->dte_cond & DTRACE_COND_OWNER) { + cred_t *cr; + cred_t *s_cr = state->dts_cred.dcr_cred; + proc_t *proc; + + ASSERT(s_cr != NULL); + + if ((cr = CRED()) == NULL || + s_cr->cr_uid != cr->cr_uid || + s_cr->cr_uid != cr->cr_ruid || + s_cr->cr_uid != cr->cr_suid || + s_cr->cr_gid != cr->cr_gid || + s_cr->cr_gid != cr->cr_rgid || + s_cr->cr_gid != cr->cr_sgid || + (proc = ttoproc(curthread)) == NULL || + (proc->p_flag & SNOCD)) { + if (mode & DTRACE_MODE_NOPRIV_DROP) + return (0); + +#ifdef illumos + mstate->dtms_access &= ~DTRACE_ACCESS_PROC; +#endif + } + } + +#ifdef illumos + /* + * If our dte_cond is set to DTRACE_COND_ZONEOWNER and we are not + * in our zone, check to see if our mode policy is to restrict rather + * than to drop; if to restrict, strip away both DTRACE_ACCESS_PROC + * and DTRACE_ACCESS_ARGS + */ + if (ecb->dte_cond & DTRACE_COND_ZONEOWNER) { + cred_t *cr; + cred_t *s_cr = state->dts_cred.dcr_cred; + + ASSERT(s_cr != NULL); + + if ((cr = CRED()) == NULL || + s_cr->cr_zone->zone_id != cr->cr_zone->zone_id) { + if (mode & DTRACE_MODE_NOPRIV_DROP) + return (0); + + mstate->dtms_access &= + ~(DTRACE_ACCESS_PROC | DTRACE_ACCESS_ARGS); + } + } +#endif + + return (1); +} + +/* + * Note: not called from probe context. This function is called + * asynchronously (and at a regular interval) from outside of probe context to + * clean the dirty dynamic variable lists on all CPUs. Dynamic variable + * cleaning is explained in detail in <sys/dtrace_impl.h>. + */ +void +dtrace_dynvar_clean(dtrace_dstate_t *dstate) +{ + dtrace_dynvar_t *dirty; + dtrace_dstate_percpu_t *dcpu; + dtrace_dynvar_t **rinsep; + int i, j, work = 0; + + for (i = 0; i < NCPU; i++) { + dcpu = &dstate->dtds_percpu[i]; + rinsep = &dcpu->dtdsc_rinsing; + + /* + * If the dirty list is NULL, there is no dirty work to do. + */ + if (dcpu->dtdsc_dirty == NULL) + continue; + + if (dcpu->dtdsc_rinsing != NULL) { + /* + * If the rinsing list is non-NULL, then it is because + * this CPU was selected to accept another CPU's + * dirty list -- and since that time, dirty buffers + * have accumulated. This is a highly unlikely + * condition, but we choose to ignore the dirty + * buffers -- they'll be picked up a future cleanse. + */ + continue; + } + + if (dcpu->dtdsc_clean != NULL) { + /* + * If the clean list is non-NULL, then we're in a + * situation where a CPU has done deallocations (we + * have a non-NULL dirty list) but no allocations (we + * also have a non-NULL clean list). We can't simply + * move the dirty list into the clean list on this + * CPU, yet we also don't want to allow this condition + * to persist, lest a short clean list prevent a + * massive dirty list from being cleaned (which in + * turn could lead to otherwise avoidable dynamic + * drops). To deal with this, we look for some CPU + * with a NULL clean list, NULL dirty list, and NULL + * rinsing list -- and then we borrow this CPU to + * rinse our dirty list. + */ + for (j = 0; j < NCPU; j++) { + dtrace_dstate_percpu_t *rinser; + + rinser = &dstate->dtds_percpu[j]; + + if (rinser->dtdsc_rinsing != NULL) + continue; + + if (rinser->dtdsc_dirty != NULL) + continue; + + if (rinser->dtdsc_clean != NULL) + continue; + + rinsep = &rinser->dtdsc_rinsing; + break; + } + + if (j == NCPU) { + /* + * We were unable to find another CPU that + * could accept this dirty list -- we are + * therefore unable to clean it now. + */ + dtrace_dynvar_failclean++; + continue; + } + } + + work = 1; + + /* + * Atomically move the dirty list aside. + */ + do { + dirty = dcpu->dtdsc_dirty; + + /* + * Before we zap the dirty list, set the rinsing list. + * (This allows for a potential assertion in + * dtrace_dynvar(): if a free dynamic variable appears + * on a hash chain, either the dirty list or the + * rinsing list for some CPU must be non-NULL.) + */ + *rinsep = dirty; + dtrace_membar_producer(); + } while (dtrace_casptr(&dcpu->dtdsc_dirty, + dirty, NULL) != dirty); + } + + if (!work) { + /* + * We have no work to do; we can simply return. + */ + return; + } + + dtrace_sync(); + + for (i = 0; i < NCPU; i++) { + dcpu = &dstate->dtds_percpu[i]; + + if (dcpu->dtdsc_rinsing == NULL) + continue; + + /* + * We are now guaranteed that no hash chain contains a pointer + * into this dirty list; we can make it clean. + */ + ASSERT(dcpu->dtdsc_clean == NULL); + dcpu->dtdsc_clean = dcpu->dtdsc_rinsing; + dcpu->dtdsc_rinsing = NULL; + } + + /* + * Before we actually set the state to be DTRACE_DSTATE_CLEAN, make + * sure that all CPUs have seen all of the dtdsc_clean pointers. + * This prevents a race whereby a CPU incorrectly decides that + * the state should be something other than DTRACE_DSTATE_CLEAN + * after dtrace_dynvar_clean() has completed. + */ + dtrace_sync(); + + dstate->dtds_state = DTRACE_DSTATE_CLEAN; +} + +/* + * Depending on the value of the op parameter, this function looks-up, + * allocates or deallocates an arbitrarily-keyed dynamic variable. If an + * allocation is requested, this function will return a pointer to a + * dtrace_dynvar_t corresponding to the allocated variable -- or NULL if no + * variable can be allocated. If NULL is returned, the appropriate counter + * will be incremented. + */ +dtrace_dynvar_t * +dtrace_dynvar(dtrace_dstate_t *dstate, uint_t nkeys, + dtrace_key_t *key, size_t dsize, dtrace_dynvar_op_t op, + dtrace_mstate_t *mstate, dtrace_vstate_t *vstate) +{ + uint64_t hashval = DTRACE_DYNHASH_VALID; + dtrace_dynhash_t *hash = dstate->dtds_hash; + dtrace_dynvar_t *free, *new_free, *next, *dvar, *start, *prev = NULL; + processorid_t me = curcpu, cpu = me; + dtrace_dstate_percpu_t *dcpu = &dstate->dtds_percpu[me]; + size_t bucket, ksize; + size_t chunksize = dstate->dtds_chunksize; + uintptr_t kdata, lock, nstate; + uint_t i; + + ASSERT(nkeys != 0); + + /* + * Hash the key. As with aggregations, we use Jenkins' "One-at-a-time" + * algorithm. For the by-value portions, we perform the algorithm in + * 16-bit chunks (as opposed to 8-bit chunks). This speeds things up a + * bit, and seems to have only a minute effect on distribution. For + * the by-reference data, we perform "One-at-a-time" iterating (safely) + * over each referenced byte. It's painful to do this, but it's much + * better than pathological hash distribution. The efficacy of the + * hashing algorithm (and a comparison with other algorithms) may be + * found by running the ::dtrace_dynstat MDB dcmd. + */ + for (i = 0; i < nkeys; i++) { + if (key[i].dttk_size == 0) { + uint64_t val = key[i].dttk_value; + + hashval += (val >> 48) & 0xffff; + hashval += (hashval << 10); + hashval ^= (hashval >> 6); + + hashval += (val >> 32) & 0xffff; + hashval += (hashval << 10); + hashval ^= (hashval >> 6); + + hashval += (val >> 16) & 0xffff; + hashval += (hashval << 10); + hashval ^= (hashval >> 6); + + hashval += val & 0xffff; + hashval += (hashval << 10); + hashval ^= (hashval >> 6); + } else { + /* + * This is incredibly painful, but it beats the hell + * out of the alternative. + */ + uint64_t j, size = key[i].dttk_size; + uintptr_t base = (uintptr_t)key[i].dttk_value; + + if (!dtrace_canload(base, size, mstate, vstate)) + break; + + for (j = 0; j < size; j++) { + hashval += dtrace_load8(base + j); + hashval += (hashval << 10); + hashval ^= (hashval >> 6); + } + } + } + + if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_FAULT)) + return (NULL); + + hashval += (hashval << 3); + hashval ^= (hashval >> 11); + hashval += (hashval << 15); + + /* + * There is a remote chance (ideally, 1 in 2^31) that our hashval + * comes out to be one of our two sentinel hash values. If this + * actually happens, we set the hashval to be a value known to be a + * non-sentinel value. + */ + if (hashval == DTRACE_DYNHASH_FREE || hashval == DTRACE_DYNHASH_SINK) + hashval = DTRACE_DYNHASH_VALID; + + /* + * Yes, it's painful to do a divide here. If the cycle count becomes + * important here, tricks can be pulled to reduce it. (However, it's + * critical that hash collisions be kept to an absolute minimum; + * they're much more painful than a divide.) It's better to have a + * solution that generates few collisions and still keeps things + * relatively simple. + */ + bucket = hashval % dstate->dtds_hashsize; + + if (op == DTRACE_DYNVAR_DEALLOC) { + volatile uintptr_t *lockp = &hash[bucket].dtdh_lock; + + for (;;) { + while ((lock = *lockp) & 1) + continue; + + if (dtrace_casptr((volatile void *)lockp, + (volatile void *)lock, (volatile void *)(lock + 1)) == (void *)lock) + break; + } + + dtrace_membar_producer(); + } + +top: + prev = NULL; + lock = hash[bucket].dtdh_lock; + + dtrace_membar_consumer(); + + start = hash[bucket].dtdh_chain; + ASSERT(start != NULL && (start->dtdv_hashval == DTRACE_DYNHASH_SINK || + start->dtdv_hashval != DTRACE_DYNHASH_FREE || + op != DTRACE_DYNVAR_DEALLOC)); + + for (dvar = start; dvar != NULL; dvar = dvar->dtdv_next) { + dtrace_tuple_t *dtuple = &dvar->dtdv_tuple; + dtrace_key_t *dkey = &dtuple->dtt_key[0]; + + if (dvar->dtdv_hashval != hashval) { + if (dvar->dtdv_hashval == DTRACE_DYNHASH_SINK) { + /* + * We've reached the sink, and therefore the + * end of the hash chain; we can kick out of + * the loop knowing that we have seen a valid + * snapshot of state. + */ + ASSERT(dvar->dtdv_next == NULL); + ASSERT(dvar == &dtrace_dynhash_sink); + break; + } + + if (dvar->dtdv_hashval == DTRACE_DYNHASH_FREE) { + /* + * We've gone off the rails: somewhere along + * the line, one of the members of this hash + * chain was deleted. Note that we could also + * detect this by simply letting this loop run + * to completion, as we would eventually hit + * the end of the dirty list. However, we + * want to avoid running the length of the + * dirty list unnecessarily (it might be quite + * long), so we catch this as early as + * possible by detecting the hash marker. In + * this case, we simply set dvar to NULL and + * break; the conditional after the loop will + * send us back to top. + */ + dvar = NULL; + break; + } + + goto next; + } + + if (dtuple->dtt_nkeys != nkeys) + goto next; + + for (i = 0; i < nkeys; i++, dkey++) { + if (dkey->dttk_size != key[i].dttk_size) + goto next; /* size or type mismatch */ + + if (dkey->dttk_size != 0) { + if (dtrace_bcmp( + (void *)(uintptr_t)key[i].dttk_value, + (void *)(uintptr_t)dkey->dttk_value, + dkey->dttk_size)) + goto next; + } else { + if (dkey->dttk_value != key[i].dttk_value) + goto next; + } + } + + if (op != DTRACE_DYNVAR_DEALLOC) + return (dvar); + + ASSERT(dvar->dtdv_next == NULL || + dvar->dtdv_next->dtdv_hashval != DTRACE_DYNHASH_FREE); + + if (prev != NULL) { + ASSERT(hash[bucket].dtdh_chain != dvar); + ASSERT(start != dvar); + ASSERT(prev->dtdv_next == dvar); + prev->dtdv_next = dvar->dtdv_next; + } else { + if (dtrace_casptr(&hash[bucket].dtdh_chain, + start, dvar->dtdv_next) != start) { + /* + * We have failed to atomically swing the + * hash table head pointer, presumably because + * of a conflicting allocation on another CPU. + * We need to reread the hash chain and try + * again. + */ + goto top; + } + } + + dtrace_membar_producer(); + + /* + * Now set the hash value to indicate that it's free. + */ + ASSERT(hash[bucket].dtdh_chain != dvar); + dvar->dtdv_hashval = DTRACE_DYNHASH_FREE; + + dtrace_membar_producer(); + + /* + * Set the next pointer to point at the dirty list, and + * atomically swing the dirty pointer to the newly freed dvar. + */ + do { + next = dcpu->dtdsc_dirty; + dvar->dtdv_next = next; + } while (dtrace_casptr(&dcpu->dtdsc_dirty, next, dvar) != next); + + /* + * Finally, unlock this hash bucket. + */ + ASSERT(hash[bucket].dtdh_lock == lock); + ASSERT(lock & 1); + hash[bucket].dtdh_lock++; + + return (NULL); +next: + prev = dvar; + continue; + } + + if (dvar == NULL) { + /* + * If dvar is NULL, it is because we went off the rails: + * one of the elements that we traversed in the hash chain + * was deleted while we were traversing it. In this case, + * we assert that we aren't doing a dealloc (deallocs lock + * the hash bucket to prevent themselves from racing with + * one another), and retry the hash chain traversal. + */ + ASSERT(op != DTRACE_DYNVAR_DEALLOC); + goto top; + } + + if (op != DTRACE_DYNVAR_ALLOC) { + /* + * If we are not to allocate a new variable, we want to + * return NULL now. Before we return, check that the value + * of the lock word hasn't changed. If it has, we may have + * seen an inconsistent snapshot. + */ + if (op == DTRACE_DYNVAR_NOALLOC) { + if (hash[bucket].dtdh_lock != lock) + goto top; + } else { + ASSERT(op == DTRACE_DYNVAR_DEALLOC); + ASSERT(hash[bucket].dtdh_lock == lock); + ASSERT(lock & 1); + hash[bucket].dtdh_lock++; + } + + return (NULL); + } + + /* + * We need to allocate a new dynamic variable. The size we need is the + * size of dtrace_dynvar plus the size of nkeys dtrace_key_t's plus the + * size of any auxiliary key data (rounded up to 8-byte alignment) plus + * the size of any referred-to data (dsize). We then round the final + * size up to the chunksize for allocation. + */ + for (ksize = 0, i = 0; i < nkeys; i++) + ksize += P2ROUNDUP(key[i].dttk_size, sizeof (uint64_t)); + + /* + * This should be pretty much impossible, but could happen if, say, + * strange DIF specified the tuple. Ideally, this should be an + * assertion and not an error condition -- but that requires that the + * chunksize calculation in dtrace_difo_chunksize() be absolutely + * bullet-proof. (That is, it must not be able to be fooled by + * malicious DIF.) Given the lack of backwards branches in DIF, + * solving this would presumably not amount to solving the Halting + * Problem -- but it still seems awfully hard. + */ + if (sizeof (dtrace_dynvar_t) + sizeof (dtrace_key_t) * (nkeys - 1) + + ksize + dsize > chunksize) { + dcpu->dtdsc_drops++; + return (NULL); + } + + nstate = DTRACE_DSTATE_EMPTY; + + do { +retry: + free = dcpu->dtdsc_free; + + if (free == NULL) { + dtrace_dynvar_t *clean = dcpu->dtdsc_clean; + void *rval; + + if (clean == NULL) { + /* + * We're out of dynamic variable space on + * this CPU. Unless we have tried all CPUs, + * we'll try to allocate from a different + * CPU. + */ + switch (dstate->dtds_state) { + case DTRACE_DSTATE_CLEAN: { + void *sp = &dstate->dtds_state; + + if (++cpu >= NCPU) + cpu = 0; + + if (dcpu->dtdsc_dirty != NULL && + nstate == DTRACE_DSTATE_EMPTY) + nstate = DTRACE_DSTATE_DIRTY; + + if (dcpu->dtdsc_rinsing != NULL) + nstate = DTRACE_DSTATE_RINSING; + + dcpu = &dstate->dtds_percpu[cpu]; + + if (cpu != me) + goto retry; + + (void) dtrace_cas32(sp, + DTRACE_DSTATE_CLEAN, nstate); + + /* + * To increment the correct bean + * counter, take another lap. + */ + goto retry; + } + + case DTRACE_DSTATE_DIRTY: + dcpu->dtdsc_dirty_drops++; + break; + + case DTRACE_DSTATE_RINSING: + dcpu->dtdsc_rinsing_drops++; + break; + + case DTRACE_DSTATE_EMPTY: + dcpu->dtdsc_drops++; + break; + } + + DTRACE_CPUFLAG_SET(CPU_DTRACE_DROP); + return (NULL); + } + + /* + * The clean list appears to be non-empty. We want to + * move the clean list to the free list; we start by + * moving the clean pointer aside. + */ + if (dtrace_casptr(&dcpu->dtdsc_clean, + clean, NULL) != clean) { + /* + * We are in one of two situations: + * + * (a) The clean list was switched to the + * free list by another CPU. + * + * (b) The clean list was added to by the + * cleansing cyclic. + * + * In either of these situations, we can + * just reattempt the free list allocation. + */ + goto retry; + } + + ASSERT(clean->dtdv_hashval == DTRACE_DYNHASH_FREE); + + /* + * Now we'll move the clean list to our free list. + * It's impossible for this to fail: the only way + * the free list can be updated is through this + * code path, and only one CPU can own the clean list. + * Thus, it would only be possible for this to fail if + * this code were racing with dtrace_dynvar_clean(). + * (That is, if dtrace_dynvar_clean() updated the clean + * list, and we ended up racing to update the free + * list.) This race is prevented by the dtrace_sync() + * in dtrace_dynvar_clean() -- which flushes the + * owners of the clean lists out before resetting + * the clean lists. + */ + dcpu = &dstate->dtds_percpu[me]; + rval = dtrace_casptr(&dcpu->dtdsc_free, NULL, clean); + ASSERT(rval == NULL); + goto retry; + } + + dvar = free; + new_free = dvar->dtdv_next; + } while (dtrace_casptr(&dcpu->dtdsc_free, free, new_free) != free); + + /* + * We have now allocated a new chunk. We copy the tuple keys into the + * tuple array and copy any referenced key data into the data space + * following the tuple array. As we do this, we relocate dttk_value + * in the final tuple to point to the key data address in the chunk. + */ + kdata = (uintptr_t)&dvar->dtdv_tuple.dtt_key[nkeys]; + dvar->dtdv_data = (void *)(kdata + ksize); + dvar->dtdv_tuple.dtt_nkeys = nkeys; + + for (i = 0; i < nkeys; i++) { + dtrace_key_t *dkey = &dvar->dtdv_tuple.dtt_key[i]; + size_t kesize = key[i].dttk_size; + + if (kesize != 0) { + dtrace_bcopy( + (const void *)(uintptr_t)key[i].dttk_value, + (void *)kdata, kesize); + dkey->dttk_value = kdata; + kdata += P2ROUNDUP(kesize, sizeof (uint64_t)); + } else { + dkey->dttk_value = key[i].dttk_value; + } + + dkey->dttk_size = kesize; + } + + ASSERT(dvar->dtdv_hashval == DTRACE_DYNHASH_FREE); + dvar->dtdv_hashval = hashval; + dvar->dtdv_next = start; + + if (dtrace_casptr(&hash[bucket].dtdh_chain, start, dvar) == start) + return (dvar); + + /* + * The cas has failed. Either another CPU is adding an element to + * this hash chain, or another CPU is deleting an element from this + * hash chain. The simplest way to deal with both of these cases + * (though not necessarily the most efficient) is to free our + * allocated block and re-attempt it all. Note that the free is + * to the dirty list and _not_ to the free list. This is to prevent + * races with allocators, above. + */ + dvar->dtdv_hashval = DTRACE_DYNHASH_FREE; + + dtrace_membar_producer(); + + do { + free = dcpu->dtdsc_dirty; + dvar->dtdv_next = free; + } while (dtrace_casptr(&dcpu->dtdsc_dirty, free, dvar) != free); + + goto top; +} + +/*ARGSUSED*/ +static void +dtrace_aggregate_min(uint64_t *oval, uint64_t nval, uint64_t arg) +{ + if ((int64_t)nval < (int64_t)*oval) + *oval = nval; +} + +/*ARGSUSED*/ +static void +dtrace_aggregate_max(uint64_t *oval, uint64_t nval, uint64_t arg) +{ + if ((int64_t)nval > (int64_t)*oval) + *oval = nval; +} + +static void +dtrace_aggregate_quantize(uint64_t *quanta, uint64_t nval, uint64_t incr) +{ + int i, zero = DTRACE_QUANTIZE_ZEROBUCKET; + int64_t val = (int64_t)nval; + + if (val < 0) { + for (i = 0; i < zero; i++) { + if (val <= DTRACE_QUANTIZE_BUCKETVAL(i)) { + quanta[i] += incr; + return; + } + } + } else { + for (i = zero + 1; i < DTRACE_QUANTIZE_NBUCKETS; i++) { + if (val < DTRACE_QUANTIZE_BUCKETVAL(i)) { + quanta[i - 1] += incr; + return; + } + } + + quanta[DTRACE_QUANTIZE_NBUCKETS - 1] += incr; + return; + } + + ASSERT(0); +} + +static void +dtrace_aggregate_lquantize(uint64_t *lquanta, uint64_t nval, uint64_t incr) +{ + uint64_t arg = *lquanta++; + int32_t base = DTRACE_LQUANTIZE_BASE(arg); + uint16_t step = DTRACE_LQUANTIZE_STEP(arg); + uint16_t levels = DTRACE_LQUANTIZE_LEVELS(arg); + int32_t val = (int32_t)nval, level; + + ASSERT(step != 0); + ASSERT(levels != 0); + + if (val < base) { + /* + * This is an underflow. + */ + lquanta[0] += incr; + return; + } + + level = (val - base) / step; + + if (level < levels) { + lquanta[level + 1] += incr; + return; + } + + /* + * This is an overflow. + */ + lquanta[levels + 1] += incr; +} + +static int +dtrace_aggregate_llquantize_bucket(uint16_t factor, uint16_t low, + uint16_t high, uint16_t nsteps, int64_t value) +{ + int64_t this = 1, last, next; + int base = 1, order; + + ASSERT(factor <= nsteps); + ASSERT(nsteps % factor == 0); + + for (order = 0; order < low; order++) + this *= factor; + + /* + * If our value is less than our factor taken to the power of the + * low order of magnitude, it goes into the zeroth bucket. + */ + if (value < (last = this)) + return (0); + + for (this *= factor; order <= high; order++) { + int nbuckets = this > nsteps ? nsteps : this; + + if ((next = this * factor) < this) { + /* + * We should not generally get log/linear quantizations + * with a high magnitude that allows 64-bits to + * overflow, but we nonetheless protect against this + * by explicitly checking for overflow, and clamping + * our value accordingly. + */ + value = this - 1; + } + + if (value < this) { + /* + * If our value lies within this order of magnitude, + * determine its position by taking the offset within + * the order of magnitude, dividing by the bucket + * width, and adding to our (accumulated) base. + */ + return (base + (value - last) / (this / nbuckets)); + } + + base += nbuckets - (nbuckets / factor); + last = this; + this = next; + } + + /* + * Our value is greater than or equal to our factor taken to the + * power of one plus the high magnitude -- return the top bucket. + */ + return (base); +} + +static void +dtrace_aggregate_llquantize(uint64_t *llquanta, uint64_t nval, uint64_t incr) +{ + uint64_t arg = *llquanta++; + uint16_t factor = DTRACE_LLQUANTIZE_FACTOR(arg); + uint16_t low = DTRACE_LLQUANTIZE_LOW(arg); + uint16_t high = DTRACE_LLQUANTIZE_HIGH(arg); + uint16_t nsteps = DTRACE_LLQUANTIZE_NSTEP(arg); + + llquanta[dtrace_aggregate_llquantize_bucket(factor, + low, high, nsteps, nval)] += incr; +} + +/*ARGSUSED*/ +static void +dtrace_aggregate_avg(uint64_t *data, uint64_t nval, uint64_t arg) +{ + data[0]++; + data[1] += nval; +} + +/*ARGSUSED*/ +static void +dtrace_aggregate_stddev(uint64_t *data, uint64_t nval, uint64_t arg) +{ + int64_t snval = (int64_t)nval; + uint64_t tmp[2]; + + data[0]++; + data[1] += nval; + + /* + * What we want to say here is: + * + * data[2] += nval * nval; + * + * But given that nval is 64-bit, we could easily overflow, so + * we do this as 128-bit arithmetic. + */ + if (snval < 0) + snval = -snval; + + dtrace_multiply_128((uint64_t)snval, (uint64_t)snval, tmp); + dtrace_add_128(data + 2, tmp, data + 2); +} + +/*ARGSUSED*/ +static void +dtrace_aggregate_count(uint64_t *oval, uint64_t nval, uint64_t arg) +{ + *oval = *oval + 1; +} + +/*ARGSUSED*/ +static void +dtrace_aggregate_sum(uint64_t *oval, uint64_t nval, uint64_t arg) +{ + *oval += nval; +} + +/* + * Aggregate given the tuple in the principal data buffer, and the aggregating + * action denoted by the specified dtrace_aggregation_t. The aggregation + * buffer is specified as the buf parameter. This routine does not return + * failure; if there is no space in the aggregation buffer, the data will be + * dropped, and a corresponding counter incremented. + */ +static void +dtrace_aggregate(dtrace_aggregation_t *agg, dtrace_buffer_t *dbuf, + intptr_t offset, dtrace_buffer_t *buf, uint64_t expr, uint64_t arg) +{ + dtrace_recdesc_t *rec = &agg->dtag_action.dta_rec; + uint32_t i, ndx, size, fsize; + uint32_t align = sizeof (uint64_t) - 1; + dtrace_aggbuffer_t *agb; + dtrace_aggkey_t *key; + uint32_t hashval = 0, limit, isstr; + caddr_t tomax, data, kdata; + dtrace_actkind_t action; + dtrace_action_t *act; + uintptr_t offs; + + if (buf == NULL) + return; + + if (!agg->dtag_hasarg) { + /* + * Currently, only quantize() and lquantize() take additional + * arguments, and they have the same semantics: an increment + * value that defaults to 1 when not present. If additional + * aggregating actions take arguments, the setting of the + * default argument value will presumably have to become more + * sophisticated... + */ + arg = 1; + } + + action = agg->dtag_action.dta_kind - DTRACEACT_AGGREGATION; + size = rec->dtrd_offset - agg->dtag_base; + fsize = size + rec->dtrd_size; + + ASSERT(dbuf->dtb_tomax != NULL); + data = dbuf->dtb_tomax + offset + agg->dtag_base; + + if ((tomax = buf->dtb_tomax) == NULL) { + dtrace_buffer_drop(buf); + return; + } + + /* + * The metastructure is always at the bottom of the buffer. + */ + agb = (dtrace_aggbuffer_t *)(tomax + buf->dtb_size - + sizeof (dtrace_aggbuffer_t)); + + if (buf->dtb_offset == 0) { + /* + * We just kludge up approximately 1/8th of the size to be + * buckets. If this guess ends up being routinely + * off-the-mark, we may need to dynamically readjust this + * based on past performance. + */ + uintptr_t hashsize = (buf->dtb_size >> 3) / sizeof (uintptr_t); + + if ((uintptr_t)agb - hashsize * sizeof (dtrace_aggkey_t *) < + (uintptr_t)tomax || hashsize == 0) { + /* + * We've been given a ludicrously small buffer; + * increment our drop count and leave. + */ + dtrace_buffer_drop(buf); + return; + } + + /* + * And now, a pathetic attempt to try to get a an odd (or + * perchance, a prime) hash size for better hash distribution. + */ + if (hashsize > (DTRACE_AGGHASHSIZE_SLEW << 3)) + hashsize -= DTRACE_AGGHASHSIZE_SLEW; + + agb->dtagb_hashsize = hashsize; + agb->dtagb_hash = (dtrace_aggkey_t **)((uintptr_t)agb - + agb->dtagb_hashsize * sizeof (dtrace_aggkey_t *)); + agb->dtagb_free = (uintptr_t)agb->dtagb_hash; + + for (i = 0; i < agb->dtagb_hashsize; i++) + agb->dtagb_hash[i] = NULL; + } + + ASSERT(agg->dtag_first != NULL); + ASSERT(agg->dtag_first->dta_intuple); + + /* + * Calculate the hash value based on the key. Note that we _don't_ + * include the aggid in the hashing (but we will store it as part of + * the key). The hashing algorithm is Bob Jenkins' "One-at-a-time" + * algorithm: a simple, quick algorithm that has no known funnels, and + * gets good distribution in practice. The efficacy of the hashing + * algorithm (and a comparison with other algorithms) may be found by + * running the ::dtrace_aggstat MDB dcmd. + */ + for (act = agg->dtag_first; act->dta_intuple; act = act->dta_next) { + i = act->dta_rec.dtrd_offset - agg->dtag_base; + limit = i + act->dta_rec.dtrd_size; + ASSERT(limit <= size); + isstr = DTRACEACT_ISSTRING(act); + + for (; i < limit; i++) { + hashval += data[i]; + hashval += (hashval << 10); + hashval ^= (hashval >> 6); + + if (isstr && data[i] == '\0') + break; + } + } + + hashval += (hashval << 3); + hashval ^= (hashval >> 11); + hashval += (hashval << 15); + + /* + * Yes, the divide here is expensive -- but it's generally the least + * of the performance issues given the amount of data that we iterate + * over to compute hash values, compare data, etc. + */ + ndx = hashval % agb->dtagb_hashsize; + + for (key = agb->dtagb_hash[ndx]; key != NULL; key = key->dtak_next) { + ASSERT((caddr_t)key >= tomax); + ASSERT((caddr_t)key < tomax + buf->dtb_size); + + if (hashval != key->dtak_hashval || key->dtak_size != size) + continue; + + kdata = key->dtak_data; + ASSERT(kdata >= tomax && kdata < tomax + buf->dtb_size); + + for (act = agg->dtag_first; act->dta_intuple; + act = act->dta_next) { + i = act->dta_rec.dtrd_offset - agg->dtag_base; + limit = i + act->dta_rec.dtrd_size; + ASSERT(limit <= size); + isstr = DTRACEACT_ISSTRING(act); + + for (; i < limit; i++) { + if (kdata[i] != data[i]) + goto next; + + if (isstr && data[i] == '\0') + break; + } + } + + if (action != key->dtak_action) { + /* + * We are aggregating on the same value in the same + * aggregation with two different aggregating actions. + * (This should have been picked up in the compiler, + * so we may be dealing with errant or devious DIF.) + * This is an error condition; we indicate as much, + * and return. + */ + DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); + return; + } + + /* + * This is a hit: we need to apply the aggregator to + * the value at this key. + */ + agg->dtag_aggregate((uint64_t *)(kdata + size), expr, arg); + return; +next: + continue; + } + + /* + * We didn't find it. We need to allocate some zero-filled space, + * link it into the hash table appropriately, and apply the aggregator + * to the (zero-filled) value. + */ + offs = buf->dtb_offset; + while (offs & (align - 1)) + offs += sizeof (uint32_t); + + /* + * If we don't have enough room to both allocate a new key _and_ + * its associated data, increment the drop count and return. + */ + if ((uintptr_t)tomax + offs + fsize > + agb->dtagb_free - sizeof (dtrace_aggkey_t)) { + dtrace_buffer_drop(buf); + return; + } + + /*CONSTCOND*/ + ASSERT(!(sizeof (dtrace_aggkey_t) & (sizeof (uintptr_t) - 1))); + key = (dtrace_aggkey_t *)(agb->dtagb_free - sizeof (dtrace_aggkey_t)); + agb->dtagb_free -= sizeof (dtrace_aggkey_t); + + key->dtak_data = kdata = tomax + offs; + buf->dtb_offset = offs + fsize; + + /* + * Now copy the data across. + */ + *((dtrace_aggid_t *)kdata) = agg->dtag_id; + + for (i = sizeof (dtrace_aggid_t); i < size; i++) + kdata[i] = data[i]; + + /* + * Because strings are not zeroed out by default, we need to iterate + * looking for actions that store strings, and we need to explicitly + * pad these strings out with zeroes. + */ + for (act = agg->dtag_first; act->dta_intuple; act = act->dta_next) { + int nul; + + if (!DTRACEACT_ISSTRING(act)) + continue; + + i = act->dta_rec.dtrd_offset - agg->dtag_base; + limit = i + act->dta_rec.dtrd_size; + ASSERT(limit <= size); + + for (nul = 0; i < limit; i++) { + if (nul) { + kdata[i] = '\0'; + continue; + } + + if (data[i] != '\0') + continue; + + nul = 1; + } + } + + for (i = size; i < fsize; i++) + kdata[i] = 0; + + key->dtak_hashval = hashval; + key->dtak_size = size; + key->dtak_action = action; + key->dtak_next = agb->dtagb_hash[ndx]; + agb->dtagb_hash[ndx] = key; + + /* + * Finally, apply the aggregator. + */ + *((uint64_t *)(key->dtak_data + size)) = agg->dtag_initial; + agg->dtag_aggregate((uint64_t *)(key->dtak_data + size), expr, arg); +} + +/* + * Given consumer state, this routine finds a speculation in the INACTIVE + * state and transitions it into the ACTIVE state. If there is no speculation + * in the INACTIVE state, 0 is returned. In this case, no error counter is + * incremented -- it is up to the caller to take appropriate action. + */ +static int +dtrace_speculation(dtrace_state_t *state) +{ + int i = 0; + dtrace_speculation_state_t curstate; + uint32_t *stat = &state->dts_speculations_unavail, count; + + while (i < state->dts_nspeculations) { + dtrace_speculation_t *spec = &state->dts_speculations[i]; + + curstate = spec->dtsp_state; + + if (curstate != DTRACESPEC_INACTIVE) { + if (curstate == DTRACESPEC_COMMITTINGMANY || + curstate == DTRACESPEC_COMMITTING || + curstate == DTRACESPEC_DISCARDING) + stat = &state->dts_speculations_busy; + i++; + continue; + } + + if (dtrace_cas32((uint32_t *)&spec->dtsp_state, + curstate, DTRACESPEC_ACTIVE) == curstate) + return (i + 1); + } + + /* + * We couldn't find a speculation. If we found as much as a single + * busy speculation buffer, we'll attribute this failure as "busy" + * instead of "unavail". + */ + do { + count = *stat; + } while (dtrace_cas32(stat, count, count + 1) != count); + + return (0); +} + +/* + * This routine commits an active speculation. If the specified speculation + * is not in a valid state to perform a commit(), this routine will silently do + * nothing. The state of the specified speculation is transitioned according + * to the state transition diagram outlined in <sys/dtrace_impl.h> + */ +static void +dtrace_speculation_commit(dtrace_state_t *state, processorid_t cpu, + dtrace_specid_t which) +{ + dtrace_speculation_t *spec; + dtrace_buffer_t *src, *dest; + uintptr_t daddr, saddr, dlimit, slimit; + dtrace_speculation_state_t curstate, new = 0; + intptr_t offs; + uint64_t timestamp; + + if (which == 0) + return; + + if (which > state->dts_nspeculations) { + cpu_core[cpu].cpuc_dtrace_flags |= CPU_DTRACE_ILLOP; + return; + } + + spec = &state->dts_speculations[which - 1]; + src = &spec->dtsp_buffer[cpu]; + dest = &state->dts_buffer[cpu]; + + do { + curstate = spec->dtsp_state; + + if (curstate == DTRACESPEC_COMMITTINGMANY) + break; + + switch (curstate) { + case DTRACESPEC_INACTIVE: + case DTRACESPEC_DISCARDING: + return; + + case DTRACESPEC_COMMITTING: + /* + * This is only possible if we are (a) commit()'ing + * without having done a prior speculate() on this CPU + * and (b) racing with another commit() on a different + * CPU. There's nothing to do -- we just assert that + * our offset is 0. + */ + ASSERT(src->dtb_offset == 0); + return; + + case DTRACESPEC_ACTIVE: + new = DTRACESPEC_COMMITTING; + break; + + case DTRACESPEC_ACTIVEONE: + /* + * This speculation is active on one CPU. If our + * buffer offset is non-zero, we know that the one CPU + * must be us. Otherwise, we are committing on a + * different CPU from the speculate(), and we must + * rely on being asynchronously cleaned. + */ + if (src->dtb_offset != 0) { + new = DTRACESPEC_COMMITTING; + break; + } + /*FALLTHROUGH*/ + + case DTRACESPEC_ACTIVEMANY: + new = DTRACESPEC_COMMITTINGMANY; + break; + + default: + ASSERT(0); + } + } while (dtrace_cas32((uint32_t *)&spec->dtsp_state, + curstate, new) != curstate); + + /* + * We have set the state to indicate that we are committing this + * speculation. Now reserve the necessary space in the destination + * buffer. + */ + if ((offs = dtrace_buffer_reserve(dest, src->dtb_offset, + sizeof (uint64_t), state, NULL)) < 0) { + dtrace_buffer_drop(dest); + goto out; + } + + /* + * We have sufficient space to copy the speculative buffer into the + * primary buffer. First, modify the speculative buffer, filling + * in the timestamp of all entries with the curstate time. The data + * must have the commit() time rather than the time it was traced, + * so that all entries in the primary buffer are in timestamp order. + */ + timestamp = dtrace_gethrtime(); + saddr = (uintptr_t)src->dtb_tomax; + slimit = saddr + src->dtb_offset; + while (saddr < slimit) { + size_t size; + dtrace_rechdr_t *dtrh = (dtrace_rechdr_t *)saddr; + + if (dtrh->dtrh_epid == DTRACE_EPIDNONE) { + saddr += sizeof (dtrace_epid_t); + continue; + } + ASSERT3U(dtrh->dtrh_epid, <=, state->dts_necbs); + size = state->dts_ecbs[dtrh->dtrh_epid - 1]->dte_size; + + ASSERT3U(saddr + size, <=, slimit); + ASSERT3U(size, >=, sizeof (dtrace_rechdr_t)); + ASSERT3U(DTRACE_RECORD_LOAD_TIMESTAMP(dtrh), ==, UINT64_MAX); + + DTRACE_RECORD_STORE_TIMESTAMP(dtrh, timestamp); + + saddr += size; + } + + /* + * Copy the buffer across. (Note that this is a + * highly subobtimal bcopy(); in the unlikely event that this becomes + * a serious performance issue, a high-performance DTrace-specific + * bcopy() should obviously be invented.) + */ + daddr = (uintptr_t)dest->dtb_tomax + offs; + dlimit = daddr + src->dtb_offset; + saddr = (uintptr_t)src->dtb_tomax; + + /* + * First, the aligned portion. + */ + while (dlimit - daddr >= sizeof (uint64_t)) { + *((uint64_t *)daddr) = *((uint64_t *)saddr); + + daddr += sizeof (uint64_t); + saddr += sizeof (uint64_t); + } + + /* + * Now any left-over bit... + */ + while (dlimit - daddr) + *((uint8_t *)daddr++) = *((uint8_t *)saddr++); + + /* + * Finally, commit the reserved space in the destination buffer. + */ + dest->dtb_offset = offs + src->dtb_offset; + +out: + /* + * If we're lucky enough to be the only active CPU on this speculation + * buffer, we can just set the state back to DTRACESPEC_INACTIVE. + */ + if (curstate == DTRACESPEC_ACTIVE || + (curstate == DTRACESPEC_ACTIVEONE && new == DTRACESPEC_COMMITTING)) { + uint32_t rval = dtrace_cas32((uint32_t *)&spec->dtsp_state, + DTRACESPEC_COMMITTING, DTRACESPEC_INACTIVE); + + ASSERT(rval == DTRACESPEC_COMMITTING); + } + + src->dtb_offset = 0; + src->dtb_xamot_drops += src->dtb_drops; + src->dtb_drops = 0; +} + +/* + * This routine discards an active speculation. If the specified speculation + * is not in a valid state to perform a discard(), this routine will silently + * do nothing. The state of the specified speculation is transitioned + * according to the state transition diagram outlined in <sys/dtrace_impl.h> + */ +static void +dtrace_speculation_discard(dtrace_state_t *state, processorid_t cpu, + dtrace_specid_t which) +{ + dtrace_speculation_t *spec; + dtrace_speculation_state_t curstate, new = 0; + dtrace_buffer_t *buf; + + if (which == 0) + return; + + if (which > state->dts_nspeculations) { + cpu_core[cpu].cpuc_dtrace_flags |= CPU_DTRACE_ILLOP; + return; + } + + spec = &state->dts_speculations[which - 1]; + buf = &spec->dtsp_buffer[cpu]; + + do { + curstate = spec->dtsp_state; + + switch (curstate) { + case DTRACESPEC_INACTIVE: + case DTRACESPEC_COMMITTINGMANY: + case DTRACESPEC_COMMITTING: + case DTRACESPEC_DISCARDING: + return; + + case DTRACESPEC_ACTIVE: + case DTRACESPEC_ACTIVEMANY: + new = DTRACESPEC_DISCARDING; + break; + + case DTRACESPEC_ACTIVEONE: + if (buf->dtb_offset != 0) { + new = DTRACESPEC_INACTIVE; + } else { + new = DTRACESPEC_DISCARDING; + } + break; + + default: + ASSERT(0); + } + } while (dtrace_cas32((uint32_t *)&spec->dtsp_state, + curstate, new) != curstate); + + buf->dtb_offset = 0; + buf->dtb_drops = 0; +} + +/* + * Note: not called from probe context. This function is called + * asynchronously from cross call context to clean any speculations that are + * in the COMMITTINGMANY or DISCARDING states. These speculations may not be + * transitioned back to the INACTIVE state until all CPUs have cleaned the + * speculation. + */ +static void +dtrace_speculation_clean_here(dtrace_state_t *state) +{ + dtrace_icookie_t cookie; + processorid_t cpu = curcpu; + dtrace_buffer_t *dest = &state->dts_buffer[cpu]; + dtrace_specid_t i; + + cookie = dtrace_interrupt_disable(); + + if (dest->dtb_tomax == NULL) { + dtrace_interrupt_enable(cookie); + return; + } + + for (i = 0; i < state->dts_nspeculations; i++) { + dtrace_speculation_t *spec = &state->dts_speculations[i]; + dtrace_buffer_t *src = &spec->dtsp_buffer[cpu]; + + if (src->dtb_tomax == NULL) + continue; + + if (spec->dtsp_state == DTRACESPEC_DISCARDING) { + src->dtb_offset = 0; + continue; + } + + if (spec->dtsp_state != DTRACESPEC_COMMITTINGMANY) + continue; + + if (src->dtb_offset == 0) + continue; + + dtrace_speculation_commit(state, cpu, i + 1); + } + + dtrace_interrupt_enable(cookie); +} + +/* + * Note: not called from probe context. This function is called + * asynchronously (and at a regular interval) to clean any speculations that + * are in the COMMITTINGMANY or DISCARDING states. If it discovers that there + * is work to be done, it cross calls all CPUs to perform that work; + * COMMITMANY and DISCARDING speculations may not be transitioned back to the + * INACTIVE state until they have been cleaned by all CPUs. + */ +static void +dtrace_speculation_clean(dtrace_state_t *state) +{ + int work = 0, rv; + dtrace_specid_t i; + + for (i = 0; i < state->dts_nspeculations; i++) { + dtrace_speculation_t *spec = &state->dts_speculations[i]; + + ASSERT(!spec->dtsp_cleaning); + + if (spec->dtsp_state != DTRACESPEC_DISCARDING && + spec->dtsp_state != DTRACESPEC_COMMITTINGMANY) + continue; + + work++; + spec->dtsp_cleaning = 1; + } + + if (!work) + return; + + dtrace_xcall(DTRACE_CPUALL, + (dtrace_xcall_t)dtrace_speculation_clean_here, state); + + /* + * We now know that all CPUs have committed or discarded their + * speculation buffers, as appropriate. We can now set the state + * to inactive. + */ + for (i = 0; i < state->dts_nspeculations; i++) { + dtrace_speculation_t *spec = &state->dts_speculations[i]; + dtrace_speculation_state_t curstate, new; + + if (!spec->dtsp_cleaning) + continue; + + curstate = spec->dtsp_state; + ASSERT(curstate == DTRACESPEC_DISCARDING || + curstate == DTRACESPEC_COMMITTINGMANY); + + new = DTRACESPEC_INACTIVE; + + rv = dtrace_cas32((uint32_t *)&spec->dtsp_state, curstate, new); + ASSERT(rv == curstate); + spec->dtsp_cleaning = 0; + } +} + +/* + * Called as part of a speculate() to get the speculative buffer associated + * with a given speculation. Returns NULL if the specified speculation is not + * in an ACTIVE state. If the speculation is in the ACTIVEONE state -- and + * the active CPU is not the specified CPU -- the speculation will be + * atomically transitioned into the ACTIVEMANY state. + */ +static dtrace_buffer_t * +dtrace_speculation_buffer(dtrace_state_t *state, processorid_t cpuid, + dtrace_specid_t which) +{ + dtrace_speculation_t *spec; + dtrace_speculation_state_t curstate, new = 0; + dtrace_buffer_t *buf; + + if (which == 0) + return (NULL); + + if (which > state->dts_nspeculations) { + cpu_core[cpuid].cpuc_dtrace_flags |= CPU_DTRACE_ILLOP; + return (NULL); + } + + spec = &state->dts_speculations[which - 1]; + buf = &spec->dtsp_buffer[cpuid]; + + do { + curstate = spec->dtsp_state; + + switch (curstate) { + case DTRACESPEC_INACTIVE: + case DTRACESPEC_COMMITTINGMANY: + case DTRACESPEC_DISCARDING: + return (NULL); + + case DTRACESPEC_COMMITTING: + ASSERT(buf->dtb_offset == 0); + return (NULL); + + case DTRACESPEC_ACTIVEONE: + /* + * This speculation is currently active on one CPU. + * Check the offset in the buffer; if it's non-zero, + * that CPU must be us (and we leave the state alone). + * If it's zero, assume that we're starting on a new + * CPU -- and change the state to indicate that the + * speculation is active on more than one CPU. + */ + if (buf->dtb_offset != 0) + return (buf); + + new = DTRACESPEC_ACTIVEMANY; + break; + + case DTRACESPEC_ACTIVEMANY: + return (buf); + + case DTRACESPEC_ACTIVE: + new = DTRACESPEC_ACTIVEONE; + break; + + default: + ASSERT(0); + } + } while (dtrace_cas32((uint32_t *)&spec->dtsp_state, + curstate, new) != curstate); + + ASSERT(new == DTRACESPEC_ACTIVEONE || new == DTRACESPEC_ACTIVEMANY); + return (buf); +} + +/* + * Return a string. In the event that the user lacks the privilege to access + * arbitrary kernel memory, we copy the string out to scratch memory so that we + * don't fail access checking. + * + * dtrace_dif_variable() uses this routine as a helper for various + * builtin values such as 'execname' and 'probefunc.' + */ +uintptr_t +dtrace_dif_varstr(uintptr_t addr, dtrace_state_t *state, + dtrace_mstate_t *mstate) +{ + uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; + uintptr_t ret; + size_t strsz; + + /* + * The easy case: this probe is allowed to read all of memory, so + * we can just return this as a vanilla pointer. + */ + if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0) + return (addr); + + /* + * This is the tougher case: we copy the string in question from + * kernel memory into scratch memory and return it that way: this + * ensures that we won't trip up when access checking tests the + * BYREF return value. + */ + strsz = dtrace_strlen((char *)addr, size) + 1; + + if (mstate->dtms_scratch_ptr + strsz > + mstate->dtms_scratch_base + mstate->dtms_scratch_size) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + return (0); + } + + dtrace_strcpy((const void *)addr, (void *)mstate->dtms_scratch_ptr, + strsz); + ret = mstate->dtms_scratch_ptr; + mstate->dtms_scratch_ptr += strsz; + return (ret); +} + +/* + * Return a string from a memoy address which is known to have one or + * more concatenated, individually zero terminated, sub-strings. + * In the event that the user lacks the privilege to access + * arbitrary kernel memory, we copy the string out to scratch memory so that we + * don't fail access checking. + * + * dtrace_dif_variable() uses this routine as a helper for various + * builtin values such as 'execargs'. + */ +static uintptr_t +dtrace_dif_varstrz(uintptr_t addr, size_t strsz, dtrace_state_t *state, + dtrace_mstate_t *mstate) +{ + char *p; + size_t i; + uintptr_t ret; + + if (mstate->dtms_scratch_ptr + strsz > + mstate->dtms_scratch_base + mstate->dtms_scratch_size) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + return (0); + } + + dtrace_bcopy((const void *)addr, (void *)mstate->dtms_scratch_ptr, + strsz); + + /* Replace sub-string termination characters with a space. */ + for (p = (char *) mstate->dtms_scratch_ptr, i = 0; i < strsz - 1; + p++, i++) + if (*p == '\0') + *p = ' '; + + ret = mstate->dtms_scratch_ptr; + mstate->dtms_scratch_ptr += strsz; + return (ret); +} + +/* + * This function implements the DIF emulator's variable lookups. The emulator + * passes a reserved variable identifier and optional built-in array index. + */ +static uint64_t +dtrace_dif_variable(dtrace_mstate_t *mstate, dtrace_state_t *state, uint64_t v, + uint64_t ndx) +{ + /* + * If we're accessing one of the uncached arguments, we'll turn this + * into a reference in the args array. + */ + if (v >= DIF_VAR_ARG0 && v <= DIF_VAR_ARG9) { + ndx = v - DIF_VAR_ARG0; + v = DIF_VAR_ARGS; + } + + switch (v) { + case DIF_VAR_ARGS: + ASSERT(mstate->dtms_present & DTRACE_MSTATE_ARGS); + if (ndx >= sizeof (mstate->dtms_arg) / + sizeof (mstate->dtms_arg[0])) { + int aframes = mstate->dtms_probe->dtpr_aframes + 2; + dtrace_provider_t *pv; + uint64_t val; + + pv = mstate->dtms_probe->dtpr_provider; + if (pv->dtpv_pops.dtps_getargval != NULL) + val = pv->dtpv_pops.dtps_getargval(pv->dtpv_arg, + mstate->dtms_probe->dtpr_id, + mstate->dtms_probe->dtpr_arg, ndx, aframes); + else + val = dtrace_getarg(ndx, aframes); + + /* + * This is regrettably required to keep the compiler + * from tail-optimizing the call to dtrace_getarg(). + * The condition always evaluates to true, but the + * compiler has no way of figuring that out a priori. + * (None of this would be necessary if the compiler + * could be relied upon to _always_ tail-optimize + * the call to dtrace_getarg() -- but it can't.) + */ + if (mstate->dtms_probe != NULL) + return (val); + + ASSERT(0); + } + + return (mstate->dtms_arg[ndx]); + +#ifdef illumos + case DIF_VAR_UREGS: { + klwp_t *lwp; + + if (!dtrace_priv_proc(state)) + return (0); + + if ((lwp = curthread->t_lwp) == NULL) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); + cpu_core[curcpu].cpuc_dtrace_illval = NULL; + return (0); + } + + return (dtrace_getreg(lwp->lwp_regs, ndx)); + return (0); + } +#else + case DIF_VAR_UREGS: { + struct trapframe *tframe; + + if (!dtrace_priv_proc(state)) + return (0); + + if ((tframe = curthread->td_frame) == NULL) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); + cpu_core[curcpu].cpuc_dtrace_illval = 0; + return (0); + } + + return (dtrace_getreg(tframe, ndx)); + } +#endif + + case DIF_VAR_CURTHREAD: + if (!dtrace_priv_proc(state)) + return (0); + return ((uint64_t)(uintptr_t)curthread); + + case DIF_VAR_TIMESTAMP: + if (!(mstate->dtms_present & DTRACE_MSTATE_TIMESTAMP)) { + mstate->dtms_timestamp = dtrace_gethrtime(); + mstate->dtms_present |= DTRACE_MSTATE_TIMESTAMP; + } + return (mstate->dtms_timestamp); + + case DIF_VAR_VTIMESTAMP: + ASSERT(dtrace_vtime_references != 0); + return (curthread->t_dtrace_vtime); + + case DIF_VAR_WALLTIMESTAMP: + if (!(mstate->dtms_present & DTRACE_MSTATE_WALLTIMESTAMP)) { + mstate->dtms_walltimestamp = dtrace_gethrestime(); + mstate->dtms_present |= DTRACE_MSTATE_WALLTIMESTAMP; + } + return (mstate->dtms_walltimestamp); + +#ifdef illumos + case DIF_VAR_IPL: + if (!dtrace_priv_kernel(state)) + return (0); + if (!(mstate->dtms_present & DTRACE_MSTATE_IPL)) { + mstate->dtms_ipl = dtrace_getipl(); + mstate->dtms_present |= DTRACE_MSTATE_IPL; + } + return (mstate->dtms_ipl); +#endif + + case DIF_VAR_EPID: + ASSERT(mstate->dtms_present & DTRACE_MSTATE_EPID); + return (mstate->dtms_epid); + + case DIF_VAR_ID: + ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE); + return (mstate->dtms_probe->dtpr_id); + + case DIF_VAR_STACKDEPTH: + if (!dtrace_priv_kernel(state)) + return (0); + if (!(mstate->dtms_present & DTRACE_MSTATE_STACKDEPTH)) { + int aframes = mstate->dtms_probe->dtpr_aframes + 2; + + mstate->dtms_stackdepth = dtrace_getstackdepth(aframes); + mstate->dtms_present |= DTRACE_MSTATE_STACKDEPTH; + } + return (mstate->dtms_stackdepth); + + case DIF_VAR_USTACKDEPTH: + if (!dtrace_priv_proc(state)) + return (0); + if (!(mstate->dtms_present & DTRACE_MSTATE_USTACKDEPTH)) { + /* + * See comment in DIF_VAR_PID. + */ + if (DTRACE_ANCHORED(mstate->dtms_probe) && + CPU_ON_INTR(CPU)) { + mstate->dtms_ustackdepth = 0; + } else { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + mstate->dtms_ustackdepth = + dtrace_getustackdepth(); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + } + mstate->dtms_present |= DTRACE_MSTATE_USTACKDEPTH; + } + return (mstate->dtms_ustackdepth); + + case DIF_VAR_CALLER: + if (!dtrace_priv_kernel(state)) + return (0); + if (!(mstate->dtms_present & DTRACE_MSTATE_CALLER)) { + int aframes = mstate->dtms_probe->dtpr_aframes + 2; + + if (!DTRACE_ANCHORED(mstate->dtms_probe)) { + /* + * If this is an unanchored probe, we are + * required to go through the slow path: + * dtrace_caller() only guarantees correct + * results for anchored probes. + */ + pc_t caller[2] = {0, 0}; + + dtrace_getpcstack(caller, 2, aframes, + (uint32_t *)(uintptr_t)mstate->dtms_arg[0]); + mstate->dtms_caller = caller[1]; + } else if ((mstate->dtms_caller = + dtrace_caller(aframes)) == -1) { + /* + * We have failed to do this the quick way; + * we must resort to the slower approach of + * calling dtrace_getpcstack(). + */ + pc_t caller = 0; + + dtrace_getpcstack(&caller, 1, aframes, NULL); + mstate->dtms_caller = caller; + } + + mstate->dtms_present |= DTRACE_MSTATE_CALLER; + } + return (mstate->dtms_caller); + + case DIF_VAR_UCALLER: + if (!dtrace_priv_proc(state)) + return (0); + + if (!(mstate->dtms_present & DTRACE_MSTATE_UCALLER)) { + uint64_t ustack[3]; + + /* + * dtrace_getupcstack() fills in the first uint64_t + * with the current PID. The second uint64_t will + * be the program counter at user-level. The third + * uint64_t will contain the caller, which is what + * we're after. + */ + ustack[2] = 0; + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + dtrace_getupcstack(ustack, 3); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + mstate->dtms_ucaller = ustack[2]; + mstate->dtms_present |= DTRACE_MSTATE_UCALLER; + } + + return (mstate->dtms_ucaller); + + case DIF_VAR_PROBEPROV: + ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE); + return (dtrace_dif_varstr( + (uintptr_t)mstate->dtms_probe->dtpr_provider->dtpv_name, + state, mstate)); + + case DIF_VAR_PROBEMOD: + ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE); + return (dtrace_dif_varstr( + (uintptr_t)mstate->dtms_probe->dtpr_mod, + state, mstate)); + + case DIF_VAR_PROBEFUNC: + ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE); + return (dtrace_dif_varstr( + (uintptr_t)mstate->dtms_probe->dtpr_func, + state, mstate)); + + case DIF_VAR_PROBENAME: + ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE); + return (dtrace_dif_varstr( + (uintptr_t)mstate->dtms_probe->dtpr_name, + state, mstate)); + + case DIF_VAR_PID: + if (!dtrace_priv_proc(state)) + return (0); + +#ifdef illumos + /* + * Note that we are assuming that an unanchored probe is + * always due to a high-level interrupt. (And we're assuming + * that there is only a single high level interrupt.) + */ + if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU)) + return (pid0.pid_id); + + /* + * It is always safe to dereference one's own t_procp pointer: + * it always points to a valid, allocated proc structure. + * Further, it is always safe to dereference the p_pidp member + * of one's own proc structure. (These are truisms becuase + * threads and processes don't clean up their own state -- + * they leave that task to whomever reaps them.) + */ + return ((uint64_t)curthread->t_procp->p_pidp->pid_id); +#else + return ((uint64_t)curproc->p_pid); +#endif + + case DIF_VAR_PPID: + if (!dtrace_priv_proc(state)) + return (0); + +#ifdef illumos + /* + * See comment in DIF_VAR_PID. + */ + if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU)) + return (pid0.pid_id); + + /* + * It is always safe to dereference one's own t_procp pointer: + * it always points to a valid, allocated proc structure. + * (This is true because threads don't clean up their own + * state -- they leave that task to whomever reaps them.) + */ + return ((uint64_t)curthread->t_procp->p_ppid); +#else + if (curproc->p_pid == proc0.p_pid) + return (curproc->p_pid); + else + return (curproc->p_pptr->p_pid); +#endif + + case DIF_VAR_TID: +#ifdef illumos + /* + * See comment in DIF_VAR_PID. + */ + if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU)) + return (0); +#endif + + return ((uint64_t)curthread->t_tid); + + case DIF_VAR_EXECARGS: { + struct pargs *p_args = curthread->td_proc->p_args; + + if (p_args == NULL) + return(0); + + return (dtrace_dif_varstrz( + (uintptr_t) p_args->ar_args, p_args->ar_length, state, mstate)); + } + + case DIF_VAR_EXECNAME: +#ifdef illumos + if (!dtrace_priv_proc(state)) + return (0); + + /* + * See comment in DIF_VAR_PID. + */ + if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU)) + return ((uint64_t)(uintptr_t)p0.p_user.u_comm); + + /* + * It is always safe to dereference one's own t_procp pointer: + * it always points to a valid, allocated proc structure. + * (This is true because threads don't clean up their own + * state -- they leave that task to whomever reaps them.) + */ + return (dtrace_dif_varstr( + (uintptr_t)curthread->t_procp->p_user.u_comm, + state, mstate)); +#else + return (dtrace_dif_varstr( + (uintptr_t) curthread->td_proc->p_comm, state, mstate)); +#endif + + case DIF_VAR_ZONENAME: +#ifdef illumos + if (!dtrace_priv_proc(state)) + return (0); + + /* + * See comment in DIF_VAR_PID. + */ + if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU)) + return ((uint64_t)(uintptr_t)p0.p_zone->zone_name); + + /* + * It is always safe to dereference one's own t_procp pointer: + * it always points to a valid, allocated proc structure. + * (This is true because threads don't clean up their own + * state -- they leave that task to whomever reaps them.) + */ + return (dtrace_dif_varstr( + (uintptr_t)curthread->t_procp->p_zone->zone_name, + state, mstate)); +#elif defined(__FreeBSD__) + /* + * On FreeBSD, we introduce compatibility to zonename by falling through + * into jailname. + */ + case DIF_VAR_JAILNAME: + if (!dtrace_priv_kernel(state)) + return (0); + + return (dtrace_dif_varstr( + (uintptr_t)curthread->td_ucred->cr_prison->pr_name, + state, mstate)); + + case DIF_VAR_JID: + if (!dtrace_priv_kernel(state)) + return (0); + + return ((uint64_t)curthread->td_ucred->cr_prison->pr_id); +#else + return (0); +#endif + + case DIF_VAR_UID: + if (!dtrace_priv_proc(state)) + return (0); + +#ifdef illumos + /* + * See comment in DIF_VAR_PID. + */ + if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU)) + return ((uint64_t)p0.p_cred->cr_uid); + + /* + * It is always safe to dereference one's own t_procp pointer: + * it always points to a valid, allocated proc structure. + * (This is true because threads don't clean up their own + * state -- they leave that task to whomever reaps them.) + * + * Additionally, it is safe to dereference one's own process + * credential, since this is never NULL after process birth. + */ + return ((uint64_t)curthread->t_procp->p_cred->cr_uid); +#else + return ((uint64_t)curthread->td_ucred->cr_uid); +#endif + + case DIF_VAR_GID: + if (!dtrace_priv_proc(state)) + return (0); + +#ifdef illumos + /* + * See comment in DIF_VAR_PID. + */ + if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU)) + return ((uint64_t)p0.p_cred->cr_gid); + + /* + * It is always safe to dereference one's own t_procp pointer: + * it always points to a valid, allocated proc structure. + * (This is true because threads don't clean up their own + * state -- they leave that task to whomever reaps them.) + * + * Additionally, it is safe to dereference one's own process + * credential, since this is never NULL after process birth. + */ + return ((uint64_t)curthread->t_procp->p_cred->cr_gid); +#else + return ((uint64_t)curthread->td_ucred->cr_gid); +#endif + + case DIF_VAR_ERRNO: { +#ifdef illumos + klwp_t *lwp; + if (!dtrace_priv_proc(state)) + return (0); + + /* + * See comment in DIF_VAR_PID. + */ + if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU)) + return (0); + + /* + * It is always safe to dereference one's own t_lwp pointer in + * the event that this pointer is non-NULL. (This is true + * because threads and lwps don't clean up their own state -- + * they leave that task to whomever reaps them.) + */ + if ((lwp = curthread->t_lwp) == NULL) + return (0); + + return ((uint64_t)lwp->lwp_errno); +#else + return (curthread->td_errno); +#endif + } +#ifndef illumos + case DIF_VAR_CPU: { + return curcpu; + } +#endif + default: + DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); + return (0); + } +} + + +typedef enum dtrace_json_state { + DTRACE_JSON_REST = 1, + DTRACE_JSON_OBJECT, + DTRACE_JSON_STRING, + DTRACE_JSON_STRING_ESCAPE, + DTRACE_JSON_STRING_ESCAPE_UNICODE, + DTRACE_JSON_COLON, + DTRACE_JSON_COMMA, + DTRACE_JSON_VALUE, + DTRACE_JSON_IDENTIFIER, + DTRACE_JSON_NUMBER, + DTRACE_JSON_NUMBER_FRAC, + DTRACE_JSON_NUMBER_EXP, + DTRACE_JSON_COLLECT_OBJECT +} dtrace_json_state_t; + +/* + * This function possesses just enough knowledge about JSON to extract a single + * value from a JSON string and store it in the scratch buffer. It is able + * to extract nested object values, and members of arrays by index. + * + * elemlist is a list of JSON keys, stored as packed NUL-terminated strings, to + * be looked up as we descend into the object tree. e.g. + * + * foo[0].bar.baz[32] --> "foo" NUL "0" NUL "bar" NUL "baz" NUL "32" NUL + * with nelems = 5. + * + * The run time of this function must be bounded above by strsize to limit the + * amount of work done in probe context. As such, it is implemented as a + * simple state machine, reading one character at a time using safe loads + * until we find the requested element, hit a parsing error or run off the + * end of the object or string. + * + * As there is no way for a subroutine to return an error without interrupting + * clause execution, we simply return NULL in the event of a missing key or any + * other error condition. Each NULL return in this function is commented with + * the error condition it represents -- parsing or otherwise. + * + * The set of states for the state machine closely matches the JSON + * specification (http://json.org/). Briefly: + * + * DTRACE_JSON_REST: + * Skip whitespace until we find either a top-level Object, moving + * to DTRACE_JSON_OBJECT; or an Array, moving to DTRACE_JSON_VALUE. + * + * DTRACE_JSON_OBJECT: + * Locate the next key String in an Object. Sets a flag to denote + * the next String as a key string and moves to DTRACE_JSON_STRING. + * + * DTRACE_JSON_COLON: + * Skip whitespace until we find the colon that separates key Strings + * from their values. Once found, move to DTRACE_JSON_VALUE. + * + * DTRACE_JSON_VALUE: + * Detects the type of the next value (String, Number, Identifier, Object + * or Array) and routes to the states that process that type. Here we also + * deal with the element selector list if we are requested to traverse down + * into the object tree. + * + * DTRACE_JSON_COMMA: + * Skip whitespace until we find the comma that separates key-value pairs + * in Objects (returning to DTRACE_JSON_OBJECT) or values in Arrays + * (similarly DTRACE_JSON_VALUE). All following literal value processing + * states return to this state at the end of their value, unless otherwise + * noted. + * + * DTRACE_JSON_NUMBER, DTRACE_JSON_NUMBER_FRAC, DTRACE_JSON_NUMBER_EXP: + * Processes a Number literal from the JSON, including any exponent + * component that may be present. Numbers are returned as strings, which + * may be passed to strtoll() if an integer is required. + * + * DTRACE_JSON_IDENTIFIER: + * Processes a "true", "false" or "null" literal in the JSON. + * + * DTRACE_JSON_STRING, DTRACE_JSON_STRING_ESCAPE, + * DTRACE_JSON_STRING_ESCAPE_UNICODE: + * Processes a String literal from the JSON, whether the String denotes + * a key, a value or part of a larger Object. Handles all escape sequences + * present in the specification, including four-digit unicode characters, + * but merely includes the escape sequence without converting it to the + * actual escaped character. If the String is flagged as a key, we + * move to DTRACE_JSON_COLON rather than DTRACE_JSON_COMMA. + * + * DTRACE_JSON_COLLECT_OBJECT: + * This state collects an entire Object (or Array), correctly handling + * embedded strings. If the full element selector list matches this nested + * object, we return the Object in full as a string. If not, we use this + * state to skip to the next value at this level and continue processing. + * + * NOTE: This function uses various macros from strtolctype.h to manipulate + * digit values, etc -- these have all been checked to ensure they make + * no additional function calls. + */ +static char * +dtrace_json(uint64_t size, uintptr_t json, char *elemlist, int nelems, + char *dest) +{ + dtrace_json_state_t state = DTRACE_JSON_REST; + int64_t array_elem = INT64_MIN; + int64_t array_pos = 0; + uint8_t escape_unicount = 0; + boolean_t string_is_key = B_FALSE; + boolean_t collect_object = B_FALSE; + boolean_t found_key = B_FALSE; + boolean_t in_array = B_FALSE; + uint32_t braces = 0, brackets = 0; + char *elem = elemlist; + char *dd = dest; + uintptr_t cur; + + for (cur = json; cur < json + size; cur++) { + char cc = dtrace_load8(cur); + if (cc == '\0') + return (NULL); + + switch (state) { + case DTRACE_JSON_REST: + if (isspace(cc)) + break; + + if (cc == '{') { + state = DTRACE_JSON_OBJECT; + break; + } + + if (cc == '[') { + in_array = B_TRUE; + array_pos = 0; + array_elem = dtrace_strtoll(elem, 10, size); + found_key = array_elem == 0 ? B_TRUE : B_FALSE; + state = DTRACE_JSON_VALUE; + break; + } + + /* + * ERROR: expected to find a top-level object or array. + */ + return (NULL); + case DTRACE_JSON_OBJECT: + if (isspace(cc)) + break; + + if (cc == '"') { + state = DTRACE_JSON_STRING; + string_is_key = B_TRUE; + break; + } + + /* + * ERROR: either the object did not start with a key + * string, or we've run off the end of the object + * without finding the requested key. + */ + return (NULL); + case DTRACE_JSON_STRING: + if (cc == '\\') { + *dd++ = '\\'; + state = DTRACE_JSON_STRING_ESCAPE; + break; + } + + if (cc == '"') { + if (collect_object) { + /* + * We don't reset the dest here, as + * the string is part of a larger + * object being collected. + */ + *dd++ = cc; + collect_object = B_FALSE; + state = DTRACE_JSON_COLLECT_OBJECT; + break; + } + *dd = '\0'; + dd = dest; /* reset string buffer */ + if (string_is_key) { + if (dtrace_strncmp(dest, elem, + size) == 0) + found_key = B_TRUE; + } else if (found_key) { + if (nelems > 1) { + /* + * We expected an object, not + * this string. + */ + return (NULL); + } + return (dest); + } + state = string_is_key ? DTRACE_JSON_COLON : + DTRACE_JSON_COMMA; + string_is_key = B_FALSE; + break; + } + + *dd++ = cc; + break; + case DTRACE_JSON_STRING_ESCAPE: + *dd++ = cc; + if (cc == 'u') { + escape_unicount = 0; + state = DTRACE_JSON_STRING_ESCAPE_UNICODE; + } else { + state = DTRACE_JSON_STRING; + } + break; + case DTRACE_JSON_STRING_ESCAPE_UNICODE: + if (!isxdigit(cc)) { + /* + * ERROR: invalid unicode escape, expected + * four valid hexidecimal digits. + */ + return (NULL); + } + + *dd++ = cc; + if (++escape_unicount == 4) + state = DTRACE_JSON_STRING; + break; + case DTRACE_JSON_COLON: + if (isspace(cc)) + break; + + if (cc == ':') { + state = DTRACE_JSON_VALUE; + break; + } + + /* + * ERROR: expected a colon. + */ + return (NULL); + case DTRACE_JSON_COMMA: + if (isspace(cc)) + break; + + if (cc == ',') { + if (in_array) { + state = DTRACE_JSON_VALUE; + if (++array_pos == array_elem) + found_key = B_TRUE; + } else { + state = DTRACE_JSON_OBJECT; + } + break; + } + + /* + * ERROR: either we hit an unexpected character, or + * we reached the end of the object or array without + * finding the requested key. + */ + return (NULL); + case DTRACE_JSON_IDENTIFIER: + if (islower(cc)) { + *dd++ = cc; + break; + } + + *dd = '\0'; + dd = dest; /* reset string buffer */ + + if (dtrace_strncmp(dest, "true", 5) == 0 || + dtrace_strncmp(dest, "false", 6) == 0 || + dtrace_strncmp(dest, "null", 5) == 0) { + if (found_key) { + if (nelems > 1) { + /* + * ERROR: We expected an object, + * not this identifier. + */ + return (NULL); + } + return (dest); + } else { + cur--; + state = DTRACE_JSON_COMMA; + break; + } + } + + /* + * ERROR: we did not recognise the identifier as one + * of those in the JSON specification. + */ + return (NULL); + case DTRACE_JSON_NUMBER: + if (cc == '.') { + *dd++ = cc; + state = DTRACE_JSON_NUMBER_FRAC; + break; + } + + if (cc == 'x' || cc == 'X') { + /* + * ERROR: specification explicitly excludes + * hexidecimal or octal numbers. + */ + return (NULL); + } + + /* FALLTHRU */ + case DTRACE_JSON_NUMBER_FRAC: + if (cc == 'e' || cc == 'E') { + *dd++ = cc; + state = DTRACE_JSON_NUMBER_EXP; + break; + } + + if (cc == '+' || cc == '-') { + /* + * ERROR: expect sign as part of exponent only. + */ + return (NULL); + } + /* FALLTHRU */ + case DTRACE_JSON_NUMBER_EXP: + if (isdigit(cc) || cc == '+' || cc == '-') { + *dd++ = cc; + break; + } + + *dd = '\0'; + dd = dest; /* reset string buffer */ + if (found_key) { + if (nelems > 1) { + /* + * ERROR: We expected an object, not + * this number. + */ + return (NULL); + } + return (dest); + } + + cur--; + state = DTRACE_JSON_COMMA; + break; + case DTRACE_JSON_VALUE: + if (isspace(cc)) + break; + + if (cc == '{' || cc == '[') { + if (nelems > 1 && found_key) { + in_array = cc == '[' ? B_TRUE : B_FALSE; + /* + * If our element selector directs us + * to descend into this nested object, + * then move to the next selector + * element in the list and restart the + * state machine. + */ + while (*elem != '\0') + elem++; + elem++; /* skip the inter-element NUL */ + nelems--; + dd = dest; + if (in_array) { + state = DTRACE_JSON_VALUE; + array_pos = 0; + array_elem = dtrace_strtoll( + elem, 10, size); + found_key = array_elem == 0 ? + B_TRUE : B_FALSE; + } else { + found_key = B_FALSE; + state = DTRACE_JSON_OBJECT; + } + break; + } + + /* + * Otherwise, we wish to either skip this + * nested object or return it in full. + */ + if (cc == '[') + brackets = 1; + else + braces = 1; + *dd++ = cc; + state = DTRACE_JSON_COLLECT_OBJECT; + break; + } + + if (cc == '"') { + state = DTRACE_JSON_STRING; + break; + } + + if (islower(cc)) { + /* + * Here we deal with true, false and null. + */ + *dd++ = cc; + state = DTRACE_JSON_IDENTIFIER; + break; + } + + if (cc == '-' || isdigit(cc)) { + *dd++ = cc; + state = DTRACE_JSON_NUMBER; + break; + } + + /* + * ERROR: unexpected character at start of value. + */ + return (NULL); + case DTRACE_JSON_COLLECT_OBJECT: + if (cc == '\0') + /* + * ERROR: unexpected end of input. + */ + return (NULL); + + *dd++ = cc; + if (cc == '"') { + collect_object = B_TRUE; + state = DTRACE_JSON_STRING; + break; + } + + if (cc == ']') { + if (brackets-- == 0) { + /* + * ERROR: unbalanced brackets. + */ + return (NULL); + } + } else if (cc == '}') { + if (braces-- == 0) { + /* + * ERROR: unbalanced braces. + */ + return (NULL); + } + } else if (cc == '{') { + braces++; + } else if (cc == '[') { + brackets++; + } + + if (brackets == 0 && braces == 0) { + if (found_key) { + *dd = '\0'; + return (dest); + } + dd = dest; /* reset string buffer */ + state = DTRACE_JSON_COMMA; + } + break; + } + } + return (NULL); +} + +/* + * Emulate the execution of DTrace ID subroutines invoked by the call opcode. + * Notice that we don't bother validating the proper number of arguments or + * their types in the tuple stack. This isn't needed because all argument + * interpretation is safe because of our load safety -- the worst that can + * happen is that a bogus program can obtain bogus results. + */ +static void +dtrace_dif_subr(uint_t subr, uint_t rd, uint64_t *regs, + dtrace_key_t *tupregs, int nargs, + dtrace_mstate_t *mstate, dtrace_state_t *state) +{ + volatile uint16_t *flags = &cpu_core[curcpu].cpuc_dtrace_flags; + volatile uintptr_t *illval = &cpu_core[curcpu].cpuc_dtrace_illval; + dtrace_vstate_t *vstate = &state->dts_vstate; + +#ifdef illumos + union { + mutex_impl_t mi; + uint64_t mx; + } m; + + union { + krwlock_t ri; + uintptr_t rw; + } r; +#else + struct thread *lowner; + union { + struct lock_object *li; + uintptr_t lx; + } l; +#endif + + switch (subr) { + case DIF_SUBR_RAND: + regs[rd] = dtrace_xoroshiro128_plus_next( + state->dts_rstate[curcpu]); + break; + +#ifdef illumos + case DIF_SUBR_MUTEX_OWNED: + if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t), + mstate, vstate)) { + regs[rd] = 0; + break; + } + + m.mx = dtrace_load64(tupregs[0].dttk_value); + if (MUTEX_TYPE_ADAPTIVE(&m.mi)) + regs[rd] = MUTEX_OWNER(&m.mi) != MUTEX_NO_OWNER; + else + regs[rd] = LOCK_HELD(&m.mi.m_spin.m_spinlock); + break; + + case DIF_SUBR_MUTEX_OWNER: + if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t), + mstate, vstate)) { + regs[rd] = 0; + break; + } + + m.mx = dtrace_load64(tupregs[0].dttk_value); + if (MUTEX_TYPE_ADAPTIVE(&m.mi) && + MUTEX_OWNER(&m.mi) != MUTEX_NO_OWNER) + regs[rd] = (uintptr_t)MUTEX_OWNER(&m.mi); + else + regs[rd] = 0; + break; + + case DIF_SUBR_MUTEX_TYPE_ADAPTIVE: + if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t), + mstate, vstate)) { + regs[rd] = 0; + break; + } + + m.mx = dtrace_load64(tupregs[0].dttk_value); + regs[rd] = MUTEX_TYPE_ADAPTIVE(&m.mi); + break; + + case DIF_SUBR_MUTEX_TYPE_SPIN: + if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t), + mstate, vstate)) { + regs[rd] = 0; + break; + } + + m.mx = dtrace_load64(tupregs[0].dttk_value); + regs[rd] = MUTEX_TYPE_SPIN(&m.mi); + break; + + case DIF_SUBR_RW_READ_HELD: { + uintptr_t tmp; + + if (!dtrace_canload(tupregs[0].dttk_value, sizeof (uintptr_t), + mstate, vstate)) { + regs[rd] = 0; + break; + } + + r.rw = dtrace_loadptr(tupregs[0].dttk_value); + regs[rd] = _RW_READ_HELD(&r.ri, tmp); + break; + } + + case DIF_SUBR_RW_WRITE_HELD: + if (!dtrace_canload(tupregs[0].dttk_value, sizeof (krwlock_t), + mstate, vstate)) { + regs[rd] = 0; + break; + } + + r.rw = dtrace_loadptr(tupregs[0].dttk_value); + regs[rd] = _RW_WRITE_HELD(&r.ri); + break; + + case DIF_SUBR_RW_ISWRITER: + if (!dtrace_canload(tupregs[0].dttk_value, sizeof (krwlock_t), + mstate, vstate)) { + regs[rd] = 0; + break; + } + + r.rw = dtrace_loadptr(tupregs[0].dttk_value); + regs[rd] = _RW_ISWRITER(&r.ri); + break; + +#else /* !illumos */ + case DIF_SUBR_MUTEX_OWNED: + if (!dtrace_canload(tupregs[0].dttk_value, + sizeof (struct lock_object), mstate, vstate)) { + regs[rd] = 0; + break; + } + l.lx = dtrace_loadptr((uintptr_t)&tupregs[0].dttk_value); + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + regs[rd] = LOCK_CLASS(l.li)->lc_owner(l.li, &lowner); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + break; + + case DIF_SUBR_MUTEX_OWNER: + if (!dtrace_canload(tupregs[0].dttk_value, + sizeof (struct lock_object), mstate, vstate)) { + regs[rd] = 0; + break; + } + l.lx = dtrace_loadptr((uintptr_t)&tupregs[0].dttk_value); + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + LOCK_CLASS(l.li)->lc_owner(l.li, &lowner); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + regs[rd] = (uintptr_t)lowner; + break; + + case DIF_SUBR_MUTEX_TYPE_ADAPTIVE: + if (!dtrace_canload(tupregs[0].dttk_value, sizeof (struct mtx), + mstate, vstate)) { + regs[rd] = 0; + break; + } + l.lx = dtrace_loadptr((uintptr_t)&tupregs[0].dttk_value); + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + regs[rd] = (LOCK_CLASS(l.li)->lc_flags & LC_SLEEPLOCK) != 0; + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + break; + + case DIF_SUBR_MUTEX_TYPE_SPIN: + if (!dtrace_canload(tupregs[0].dttk_value, sizeof (struct mtx), + mstate, vstate)) { + regs[rd] = 0; + break; + } + l.lx = dtrace_loadptr((uintptr_t)&tupregs[0].dttk_value); + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + regs[rd] = (LOCK_CLASS(l.li)->lc_flags & LC_SPINLOCK) != 0; + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + break; + + case DIF_SUBR_RW_READ_HELD: + case DIF_SUBR_SX_SHARED_HELD: + if (!dtrace_canload(tupregs[0].dttk_value, sizeof (uintptr_t), + mstate, vstate)) { + regs[rd] = 0; + break; + } + l.lx = dtrace_loadptr((uintptr_t)&tupregs[0].dttk_value); + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + regs[rd] = LOCK_CLASS(l.li)->lc_owner(l.li, &lowner) && + lowner == NULL; + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + break; + + case DIF_SUBR_RW_WRITE_HELD: + case DIF_SUBR_SX_EXCLUSIVE_HELD: + if (!dtrace_canload(tupregs[0].dttk_value, sizeof (uintptr_t), + mstate, vstate)) { + regs[rd] = 0; + break; + } + l.lx = dtrace_loadptr(tupregs[0].dttk_value); + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + regs[rd] = LOCK_CLASS(l.li)->lc_owner(l.li, &lowner) && + lowner != NULL; + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + break; + + case DIF_SUBR_RW_ISWRITER: + case DIF_SUBR_SX_ISEXCLUSIVE: + if (!dtrace_canload(tupregs[0].dttk_value, sizeof (uintptr_t), + mstate, vstate)) { + regs[rd] = 0; + break; + } + l.lx = dtrace_loadptr(tupregs[0].dttk_value); + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + LOCK_CLASS(l.li)->lc_owner(l.li, &lowner); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + regs[rd] = (lowner == curthread); + break; +#endif /* illumos */ + + case DIF_SUBR_BCOPY: { + /* + * We need to be sure that the destination is in the scratch + * region -- no other region is allowed. + */ + uintptr_t src = tupregs[0].dttk_value; + uintptr_t dest = tupregs[1].dttk_value; + size_t size = tupregs[2].dttk_value; + + if (!dtrace_inscratch(dest, size, mstate)) { + *flags |= CPU_DTRACE_BADADDR; + *illval = regs[rd]; + break; + } + + if (!dtrace_canload(src, size, mstate, vstate)) { + regs[rd] = 0; + break; + } + + dtrace_bcopy((void *)src, (void *)dest, size); + break; + } + + case DIF_SUBR_ALLOCA: + case DIF_SUBR_COPYIN: { + uintptr_t dest = P2ROUNDUP(mstate->dtms_scratch_ptr, 8); + uint64_t size = + tupregs[subr == DIF_SUBR_ALLOCA ? 0 : 1].dttk_value; + size_t scratch_size = (dest - mstate->dtms_scratch_ptr) + size; + + /* + * This action doesn't require any credential checks since + * probes will not activate in user contexts to which the + * enabling user does not have permissions. + */ + + /* + * Rounding up the user allocation size could have overflowed + * a large, bogus allocation (like -1ULL) to 0. + */ + if (scratch_size < size || + !DTRACE_INSCRATCH(mstate, scratch_size)) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + regs[rd] = 0; + break; + } + + if (subr == DIF_SUBR_COPYIN) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + dtrace_copyin(tupregs[0].dttk_value, dest, size, flags); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + } + + mstate->dtms_scratch_ptr += scratch_size; + regs[rd] = dest; + break; + } + + case DIF_SUBR_COPYINTO: { + uint64_t size = tupregs[1].dttk_value; + uintptr_t dest = tupregs[2].dttk_value; + + /* + * This action doesn't require any credential checks since + * probes will not activate in user contexts to which the + * enabling user does not have permissions. + */ + if (!dtrace_inscratch(dest, size, mstate)) { + *flags |= CPU_DTRACE_BADADDR; + *illval = regs[rd]; + break; + } + + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + dtrace_copyin(tupregs[0].dttk_value, dest, size, flags); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + break; + } + + case DIF_SUBR_COPYINSTR: { + uintptr_t dest = mstate->dtms_scratch_ptr; + uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; + + if (nargs > 1 && tupregs[1].dttk_value < size) + size = tupregs[1].dttk_value + 1; + + /* + * This action doesn't require any credential checks since + * probes will not activate in user contexts to which the + * enabling user does not have permissions. + */ + if (!DTRACE_INSCRATCH(mstate, size)) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + regs[rd] = 0; + break; + } + + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + dtrace_copyinstr(tupregs[0].dttk_value, dest, size, flags); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + + ((char *)dest)[size - 1] = '\0'; + mstate->dtms_scratch_ptr += size; + regs[rd] = dest; + break; + } + +#ifdef illumos + case DIF_SUBR_MSGSIZE: + case DIF_SUBR_MSGDSIZE: { + uintptr_t baddr = tupregs[0].dttk_value, daddr; + uintptr_t wptr, rptr; + size_t count = 0; + int cont = 0; + + while (baddr != 0 && !(*flags & CPU_DTRACE_FAULT)) { + + if (!dtrace_canload(baddr, sizeof (mblk_t), mstate, + vstate)) { + regs[rd] = 0; + break; + } + + wptr = dtrace_loadptr(baddr + + offsetof(mblk_t, b_wptr)); + + rptr = dtrace_loadptr(baddr + + offsetof(mblk_t, b_rptr)); + + if (wptr < rptr) { + *flags |= CPU_DTRACE_BADADDR; + *illval = tupregs[0].dttk_value; + break; + } + + daddr = dtrace_loadptr(baddr + + offsetof(mblk_t, b_datap)); + + baddr = dtrace_loadptr(baddr + + offsetof(mblk_t, b_cont)); + + /* + * We want to prevent against denial-of-service here, + * so we're only going to search the list for + * dtrace_msgdsize_max mblks. + */ + if (cont++ > dtrace_msgdsize_max) { + *flags |= CPU_DTRACE_ILLOP; + break; + } + + if (subr == DIF_SUBR_MSGDSIZE) { + if (dtrace_load8(daddr + + offsetof(dblk_t, db_type)) != M_DATA) + continue; + } + + count += wptr - rptr; + } + + if (!(*flags & CPU_DTRACE_FAULT)) + regs[rd] = count; + + break; + } +#endif + + case DIF_SUBR_PROGENYOF: { + pid_t pid = tupregs[0].dttk_value; + proc_t *p; + int rval = 0; + + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + + for (p = curthread->t_procp; p != NULL; p = p->p_parent) { +#ifdef illumos + if (p->p_pidp->pid_id == pid) { +#else + if (p->p_pid == pid) { +#endif + rval = 1; + break; + } + } + + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + + regs[rd] = rval; + break; + } + + case DIF_SUBR_SPECULATION: + regs[rd] = dtrace_speculation(state); + break; + + case DIF_SUBR_COPYOUT: { + uintptr_t kaddr = tupregs[0].dttk_value; + uintptr_t uaddr = tupregs[1].dttk_value; + uint64_t size = tupregs[2].dttk_value; + + if (!dtrace_destructive_disallow && + dtrace_priv_proc_control(state) && + !dtrace_istoxic(kaddr, size) && + dtrace_canload(kaddr, size, mstate, vstate)) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + dtrace_copyout(kaddr, uaddr, size, flags); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + } + break; + } + + case DIF_SUBR_COPYOUTSTR: { + uintptr_t kaddr = tupregs[0].dttk_value; + uintptr_t uaddr = tupregs[1].dttk_value; + uint64_t size = tupregs[2].dttk_value; + size_t lim; + + if (!dtrace_destructive_disallow && + dtrace_priv_proc_control(state) && + !dtrace_istoxic(kaddr, size) && + dtrace_strcanload(kaddr, size, &lim, mstate, vstate)) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + dtrace_copyoutstr(kaddr, uaddr, lim, flags); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + } + break; + } + + case DIF_SUBR_STRLEN: { + size_t size = state->dts_options[DTRACEOPT_STRSIZE]; + uintptr_t addr = (uintptr_t)tupregs[0].dttk_value; + size_t lim; + + if (!dtrace_strcanload(addr, size, &lim, mstate, vstate)) { + regs[rd] = 0; + break; + } + + regs[rd] = dtrace_strlen((char *)addr, lim); + break; + } + + case DIF_SUBR_STRCHR: + case DIF_SUBR_STRRCHR: { + /* + * We're going to iterate over the string looking for the + * specified character. We will iterate until we have reached + * the string length or we have found the character. If this + * is DIF_SUBR_STRRCHR, we will look for the last occurrence + * of the specified character instead of the first. + */ + uintptr_t addr = tupregs[0].dttk_value; + uintptr_t addr_limit; + uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; + size_t lim; + char c, target = (char)tupregs[1].dttk_value; + + if (!dtrace_strcanload(addr, size, &lim, mstate, vstate)) { + regs[rd] = 0; + break; + } + addr_limit = addr + lim; + + for (regs[rd] = 0; addr < addr_limit; addr++) { + if ((c = dtrace_load8(addr)) == target) { + regs[rd] = addr; + + if (subr == DIF_SUBR_STRCHR) + break; + } + + if (c == '\0') + break; + } + break; + } + + case DIF_SUBR_STRSTR: + case DIF_SUBR_INDEX: + case DIF_SUBR_RINDEX: { + /* + * We're going to iterate over the string looking for the + * specified string. We will iterate until we have reached + * the string length or we have found the string. (Yes, this + * is done in the most naive way possible -- but considering + * that the string we're searching for is likely to be + * relatively short, the complexity of Rabin-Karp or similar + * hardly seems merited.) + */ + char *addr = (char *)(uintptr_t)tupregs[0].dttk_value; + char *substr = (char *)(uintptr_t)tupregs[1].dttk_value; + uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; + size_t len = dtrace_strlen(addr, size); + size_t sublen = dtrace_strlen(substr, size); + char *limit = addr + len, *orig = addr; + int notfound = subr == DIF_SUBR_STRSTR ? 0 : -1; + int inc = 1; + + regs[rd] = notfound; + + if (!dtrace_canload((uintptr_t)addr, len + 1, mstate, vstate)) { + regs[rd] = 0; + break; + } + + if (!dtrace_canload((uintptr_t)substr, sublen + 1, mstate, + vstate)) { + regs[rd] = 0; + break; + } + + /* + * strstr() and index()/rindex() have similar semantics if + * both strings are the empty string: strstr() returns a + * pointer to the (empty) string, and index() and rindex() + * both return index 0 (regardless of any position argument). + */ + if (sublen == 0 && len == 0) { + if (subr == DIF_SUBR_STRSTR) + regs[rd] = (uintptr_t)addr; + else + regs[rd] = 0; + break; + } + + if (subr != DIF_SUBR_STRSTR) { + if (subr == DIF_SUBR_RINDEX) { + limit = orig - 1; + addr += len; + inc = -1; + } + + /* + * Both index() and rindex() take an optional position + * argument that denotes the starting position. + */ + if (nargs == 3) { + int64_t pos = (int64_t)tupregs[2].dttk_value; + + /* + * If the position argument to index() is + * negative, Perl implicitly clamps it at + * zero. This semantic is a little surprising + * given the special meaning of negative + * positions to similar Perl functions like + * substr(), but it appears to reflect a + * notion that index() can start from a + * negative index and increment its way up to + * the string. Given this notion, Perl's + * rindex() is at least self-consistent in + * that it implicitly clamps positions greater + * than the string length to be the string + * length. Where Perl completely loses + * coherence, however, is when the specified + * substring is the empty string (""). In + * this case, even if the position is + * negative, rindex() returns 0 -- and even if + * the position is greater than the length, + * index() returns the string length. These + * semantics violate the notion that index() + * should never return a value less than the + * specified position and that rindex() should + * never return a value greater than the + * specified position. (One assumes that + * these semantics are artifacts of Perl's + * implementation and not the results of + * deliberate design -- it beggars belief that + * even Larry Wall could desire such oddness.) + * While in the abstract one would wish for + * consistent position semantics across + * substr(), index() and rindex() -- or at the + * very least self-consistent position + * semantics for index() and rindex() -- we + * instead opt to keep with the extant Perl + * semantics, in all their broken glory. (Do + * we have more desire to maintain Perl's + * semantics than Perl does? Probably.) + */ + if (subr == DIF_SUBR_RINDEX) { + if (pos < 0) { + if (sublen == 0) + regs[rd] = 0; + break; + } + + if (pos > len) + pos = len; + } else { + if (pos < 0) + pos = 0; + + if (pos >= len) { + if (sublen == 0) + regs[rd] = len; + break; + } + } + + addr = orig + pos; + } + } + + for (regs[rd] = notfound; addr != limit; addr += inc) { + if (dtrace_strncmp(addr, substr, sublen) == 0) { + if (subr != DIF_SUBR_STRSTR) { + /* + * As D index() and rindex() are + * modeled on Perl (and not on awk), + * we return a zero-based (and not a + * one-based) index. (For you Perl + * weenies: no, we're not going to add + * $[ -- and shouldn't you be at a con + * or something?) + */ + regs[rd] = (uintptr_t)(addr - orig); + break; + } + + ASSERT(subr == DIF_SUBR_STRSTR); + regs[rd] = (uintptr_t)addr; + break; + } + } + + break; + } + + case DIF_SUBR_STRTOK: { + uintptr_t addr = tupregs[0].dttk_value; + uintptr_t tokaddr = tupregs[1].dttk_value; + uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; + uintptr_t limit, toklimit; + size_t clim; + uint8_t c = 0, tokmap[32]; /* 256 / 8 */ + char *dest = (char *)mstate->dtms_scratch_ptr; + int i; + + /* + * Check both the token buffer and (later) the input buffer, + * since both could be non-scratch addresses. + */ + if (!dtrace_strcanload(tokaddr, size, &clim, mstate, vstate)) { + regs[rd] = 0; + break; + } + toklimit = tokaddr + clim; + + if (!DTRACE_INSCRATCH(mstate, size)) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + regs[rd] = 0; + break; + } + + if (addr == 0) { + /* + * If the address specified is NULL, we use our saved + * strtok pointer from the mstate. Note that this + * means that the saved strtok pointer is _only_ + * valid within multiple enablings of the same probe -- + * it behaves like an implicit clause-local variable. + */ + addr = mstate->dtms_strtok; + limit = mstate->dtms_strtok_limit; + } else { + /* + * If the user-specified address is non-NULL we must + * access check it. This is the only time we have + * a chance to do so, since this address may reside + * in the string table of this clause-- future calls + * (when we fetch addr from mstate->dtms_strtok) + * would fail this access check. + */ + if (!dtrace_strcanload(addr, size, &clim, mstate, + vstate)) { + regs[rd] = 0; + break; + } + limit = addr + clim; + } + + /* + * First, zero the token map, and then process the token + * string -- setting a bit in the map for every character + * found in the token string. + */ + for (i = 0; i < sizeof (tokmap); i++) + tokmap[i] = 0; + + for (; tokaddr < toklimit; tokaddr++) { + if ((c = dtrace_load8(tokaddr)) == '\0') + break; + + ASSERT((c >> 3) < sizeof (tokmap)); + tokmap[c >> 3] |= (1 << (c & 0x7)); + } + + for (; addr < limit; addr++) { + /* + * We're looking for a character that is _not_ + * contained in the token string. + */ + if ((c = dtrace_load8(addr)) == '\0') + break; + + if (!(tokmap[c >> 3] & (1 << (c & 0x7)))) + break; + } + + if (c == '\0') { + /* + * We reached the end of the string without finding + * any character that was not in the token string. + * We return NULL in this case, and we set the saved + * address to NULL as well. + */ + regs[rd] = 0; + mstate->dtms_strtok = 0; + mstate->dtms_strtok_limit = 0; + break; + } + + /* + * From here on, we're copying into the destination string. + */ + for (i = 0; addr < limit && i < size - 1; addr++) { + if ((c = dtrace_load8(addr)) == '\0') + break; + + if (tokmap[c >> 3] & (1 << (c & 0x7))) + break; + + ASSERT(i < size); + dest[i++] = c; + } + + ASSERT(i < size); + dest[i] = '\0'; + regs[rd] = (uintptr_t)dest; + mstate->dtms_scratch_ptr += size; + mstate->dtms_strtok = addr; + mstate->dtms_strtok_limit = limit; + break; + } + + case DIF_SUBR_SUBSTR: { + uintptr_t s = tupregs[0].dttk_value; + uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; + char *d = (char *)mstate->dtms_scratch_ptr; + int64_t index = (int64_t)tupregs[1].dttk_value; + int64_t remaining = (int64_t)tupregs[2].dttk_value; + size_t len = dtrace_strlen((char *)s, size); + int64_t i; + + if (!dtrace_canload(s, len + 1, mstate, vstate)) { + regs[rd] = 0; + break; + } + + if (!DTRACE_INSCRATCH(mstate, size)) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + regs[rd] = 0; + break; + } + + if (nargs <= 2) + remaining = (int64_t)size; + + if (index < 0) { + index += len; + + if (index < 0 && index + remaining > 0) { + remaining += index; + index = 0; + } + } + + if (index >= len || index < 0) { + remaining = 0; + } else if (remaining < 0) { + remaining += len - index; + } else if (index + remaining > size) { + remaining = size - index; + } + + for (i = 0; i < remaining; i++) { + if ((d[i] = dtrace_load8(s + index + i)) == '\0') + break; + } + + d[i] = '\0'; + + mstate->dtms_scratch_ptr += size; + regs[rd] = (uintptr_t)d; + break; + } + + case DIF_SUBR_JSON: { + uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; + uintptr_t json = tupregs[0].dttk_value; + size_t jsonlen = dtrace_strlen((char *)json, size); + uintptr_t elem = tupregs[1].dttk_value; + size_t elemlen = dtrace_strlen((char *)elem, size); + + char *dest = (char *)mstate->dtms_scratch_ptr; + char *elemlist = (char *)mstate->dtms_scratch_ptr + jsonlen + 1; + char *ee = elemlist; + int nelems = 1; + uintptr_t cur; + + if (!dtrace_canload(json, jsonlen + 1, mstate, vstate) || + !dtrace_canload(elem, elemlen + 1, mstate, vstate)) { + regs[rd] = 0; + break; + } + + if (!DTRACE_INSCRATCH(mstate, jsonlen + 1 + elemlen + 1)) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + regs[rd] = 0; + break; + } + + /* + * Read the element selector and split it up into a packed list + * of strings. + */ + for (cur = elem; cur < elem + elemlen; cur++) { + char cc = dtrace_load8(cur); + + if (cur == elem && cc == '[') { + /* + * If the first element selector key is + * actually an array index then ignore the + * bracket. + */ + continue; + } + + if (cc == ']') + continue; + + if (cc == '.' || cc == '[') { + nelems++; + cc = '\0'; + } + + *ee++ = cc; + } + *ee++ = '\0'; + + if ((regs[rd] = (uintptr_t)dtrace_json(size, json, elemlist, + nelems, dest)) != 0) + mstate->dtms_scratch_ptr += jsonlen + 1; + break; + } + + case DIF_SUBR_TOUPPER: + case DIF_SUBR_TOLOWER: { + uintptr_t s = tupregs[0].dttk_value; + uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; + char *dest = (char *)mstate->dtms_scratch_ptr, c; + size_t len = dtrace_strlen((char *)s, size); + char lower, upper, convert; + int64_t i; + + if (subr == DIF_SUBR_TOUPPER) { + lower = 'a'; + upper = 'z'; + convert = 'A'; + } else { + lower = 'A'; + upper = 'Z'; + convert = 'a'; + } + + if (!dtrace_canload(s, len + 1, mstate, vstate)) { + regs[rd] = 0; + break; + } + + if (!DTRACE_INSCRATCH(mstate, size)) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + regs[rd] = 0; + break; + } + + for (i = 0; i < size - 1; i++) { + if ((c = dtrace_load8(s + i)) == '\0') + break; + + if (c >= lower && c <= upper) + c = convert + (c - lower); + + dest[i] = c; + } + + ASSERT(i < size); + dest[i] = '\0'; + regs[rd] = (uintptr_t)dest; + mstate->dtms_scratch_ptr += size; + break; + } + +#ifdef illumos + case DIF_SUBR_GETMAJOR: +#ifdef _LP64 + regs[rd] = (tupregs[0].dttk_value >> NBITSMINOR64) & MAXMAJ64; +#else + regs[rd] = (tupregs[0].dttk_value >> NBITSMINOR) & MAXMAJ; +#endif + break; + + case DIF_SUBR_GETMINOR: +#ifdef _LP64 + regs[rd] = tupregs[0].dttk_value & MAXMIN64; +#else + regs[rd] = tupregs[0].dttk_value & MAXMIN; +#endif + break; + + case DIF_SUBR_DDI_PATHNAME: { + /* + * This one is a galactic mess. We are going to roughly + * emulate ddi_pathname(), but it's made more complicated + * by the fact that we (a) want to include the minor name and + * (b) must proceed iteratively instead of recursively. + */ + uintptr_t dest = mstate->dtms_scratch_ptr; + uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; + char *start = (char *)dest, *end = start + size - 1; + uintptr_t daddr = tupregs[0].dttk_value; + int64_t minor = (int64_t)tupregs[1].dttk_value; + char *s; + int i, len, depth = 0; + + /* + * Due to all the pointer jumping we do and context we must + * rely upon, we just mandate that the user must have kernel + * read privileges to use this routine. + */ + if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) == 0) { + *flags |= CPU_DTRACE_KPRIV; + *illval = daddr; + regs[rd] = 0; + } + + if (!DTRACE_INSCRATCH(mstate, size)) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + regs[rd] = 0; + break; + } + + *end = '\0'; + + /* + * We want to have a name for the minor. In order to do this, + * we need to walk the minor list from the devinfo. We want + * to be sure that we don't infinitely walk a circular list, + * so we check for circularity by sending a scout pointer + * ahead two elements for every element that we iterate over; + * if the list is circular, these will ultimately point to the + * same element. You may recognize this little trick as the + * answer to a stupid interview question -- one that always + * seems to be asked by those who had to have it laboriously + * explained to them, and who can't even concisely describe + * the conditions under which one would be forced to resort to + * this technique. Needless to say, those conditions are + * found here -- and probably only here. Is this the only use + * of this infamous trick in shipping, production code? If it + * isn't, it probably should be... + */ + if (minor != -1) { + uintptr_t maddr = dtrace_loadptr(daddr + + offsetof(struct dev_info, devi_minor)); + + uintptr_t next = offsetof(struct ddi_minor_data, next); + uintptr_t name = offsetof(struct ddi_minor_data, + d_minor) + offsetof(struct ddi_minor, name); + uintptr_t dev = offsetof(struct ddi_minor_data, + d_minor) + offsetof(struct ddi_minor, dev); + uintptr_t scout; + + if (maddr != NULL) + scout = dtrace_loadptr(maddr + next); + + while (maddr != NULL && !(*flags & CPU_DTRACE_FAULT)) { + uint64_t m; +#ifdef _LP64 + m = dtrace_load64(maddr + dev) & MAXMIN64; +#else + m = dtrace_load32(maddr + dev) & MAXMIN; +#endif + if (m != minor) { + maddr = dtrace_loadptr(maddr + next); + + if (scout == NULL) + continue; + + scout = dtrace_loadptr(scout + next); + + if (scout == NULL) + continue; + + scout = dtrace_loadptr(scout + next); + + if (scout == NULL) + continue; + + if (scout == maddr) { + *flags |= CPU_DTRACE_ILLOP; + break; + } + + continue; + } + + /* + * We have the minor data. Now we need to + * copy the minor's name into the end of the + * pathname. + */ + s = (char *)dtrace_loadptr(maddr + name); + len = dtrace_strlen(s, size); + + if (*flags & CPU_DTRACE_FAULT) + break; + + if (len != 0) { + if ((end -= (len + 1)) < start) + break; + + *end = ':'; + } + + for (i = 1; i <= len; i++) + end[i] = dtrace_load8((uintptr_t)s++); + break; + } + } + + while (daddr != NULL && !(*flags & CPU_DTRACE_FAULT)) { + ddi_node_state_t devi_state; + + devi_state = dtrace_load32(daddr + + offsetof(struct dev_info, devi_node_state)); + + if (*flags & CPU_DTRACE_FAULT) + break; + + if (devi_state >= DS_INITIALIZED) { + s = (char *)dtrace_loadptr(daddr + + offsetof(struct dev_info, devi_addr)); + len = dtrace_strlen(s, size); + + if (*flags & CPU_DTRACE_FAULT) + break; + + if (len != 0) { + if ((end -= (len + 1)) < start) + break; + + *end = '@'; + } + + for (i = 1; i <= len; i++) + end[i] = dtrace_load8((uintptr_t)s++); + } + + /* + * Now for the node name... + */ + s = (char *)dtrace_loadptr(daddr + + offsetof(struct dev_info, devi_node_name)); + + daddr = dtrace_loadptr(daddr + + offsetof(struct dev_info, devi_parent)); + + /* + * If our parent is NULL (that is, if we're the root + * node), we're going to use the special path + * "devices". + */ + if (daddr == 0) + s = "devices"; + + len = dtrace_strlen(s, size); + if (*flags & CPU_DTRACE_FAULT) + break; + + if ((end -= (len + 1)) < start) + break; + + for (i = 1; i <= len; i++) + end[i] = dtrace_load8((uintptr_t)s++); + *end = '/'; + + if (depth++ > dtrace_devdepth_max) { + *flags |= CPU_DTRACE_ILLOP; + break; + } + } + + if (end < start) + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + + if (daddr == 0) { + regs[rd] = (uintptr_t)end; + mstate->dtms_scratch_ptr += size; + } + + break; + } +#endif + + case DIF_SUBR_STRJOIN: { + char *d = (char *)mstate->dtms_scratch_ptr; + uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; + uintptr_t s1 = tupregs[0].dttk_value; + uintptr_t s2 = tupregs[1].dttk_value; + int i = 0, j = 0; + size_t lim1, lim2; + char c; + + if (!dtrace_strcanload(s1, size, &lim1, mstate, vstate) || + !dtrace_strcanload(s2, size, &lim2, mstate, vstate)) { + regs[rd] = 0; + break; + } + + if (!DTRACE_INSCRATCH(mstate, size)) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + regs[rd] = 0; + break; + } + + for (;;) { + if (i >= size) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + regs[rd] = 0; + break; + } + c = (i >= lim1) ? '\0' : dtrace_load8(s1++); + if ((d[i++] = c) == '\0') { + i--; + break; + } + } + + for (;;) { + if (i >= size) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + regs[rd] = 0; + break; + } + + c = (j++ >= lim2) ? '\0' : dtrace_load8(s2++); + if ((d[i++] = c) == '\0') + break; + } + + if (i < size) { + mstate->dtms_scratch_ptr += i; + regs[rd] = (uintptr_t)d; + } + + break; + } + + case DIF_SUBR_STRTOLL: { + uintptr_t s = tupregs[0].dttk_value; + uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; + size_t lim; + int base = 10; + + if (nargs > 1) { + if ((base = tupregs[1].dttk_value) <= 1 || + base > ('z' - 'a' + 1) + ('9' - '0' + 1)) { + *flags |= CPU_DTRACE_ILLOP; + break; + } + } + + if (!dtrace_strcanload(s, size, &lim, mstate, vstate)) { + regs[rd] = INT64_MIN; + break; + } + + regs[rd] = dtrace_strtoll((char *)s, base, lim); + break; + } + + case DIF_SUBR_LLTOSTR: { + int64_t i = (int64_t)tupregs[0].dttk_value; + uint64_t val, digit; + uint64_t size = 65; /* enough room for 2^64 in binary */ + char *end = (char *)mstate->dtms_scratch_ptr + size - 1; + int base = 10; + + if (nargs > 1) { + if ((base = tupregs[1].dttk_value) <= 1 || + base > ('z' - 'a' + 1) + ('9' - '0' + 1)) { + *flags |= CPU_DTRACE_ILLOP; + break; + } + } + + val = (base == 10 && i < 0) ? i * -1 : i; + + if (!DTRACE_INSCRATCH(mstate, size)) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + regs[rd] = 0; + break; + } + + for (*end-- = '\0'; val; val /= base) { + if ((digit = val % base) <= '9' - '0') { + *end-- = '0' + digit; + } else { + *end-- = 'a' + (digit - ('9' - '0') - 1); + } + } + + if (i == 0 && base == 16) + *end-- = '0'; + + if (base == 16) + *end-- = 'x'; + + if (i == 0 || base == 8 || base == 16) + *end-- = '0'; + + if (i < 0 && base == 10) + *end-- = '-'; + + regs[rd] = (uintptr_t)end + 1; + mstate->dtms_scratch_ptr += size; + break; + } + + case DIF_SUBR_HTONS: + case DIF_SUBR_NTOHS: +#if BYTE_ORDER == BIG_ENDIAN + regs[rd] = (uint16_t)tupregs[0].dttk_value; +#else + regs[rd] = DT_BSWAP_16((uint16_t)tupregs[0].dttk_value); +#endif + break; + + + case DIF_SUBR_HTONL: + case DIF_SUBR_NTOHL: +#if BYTE_ORDER == BIG_ENDIAN + regs[rd] = (uint32_t)tupregs[0].dttk_value; +#else + regs[rd] = DT_BSWAP_32((uint32_t)tupregs[0].dttk_value); +#endif + break; + + + case DIF_SUBR_HTONLL: + case DIF_SUBR_NTOHLL: +#if BYTE_ORDER == BIG_ENDIAN + regs[rd] = (uint64_t)tupregs[0].dttk_value; +#else + regs[rd] = DT_BSWAP_64((uint64_t)tupregs[0].dttk_value); +#endif + break; + + + case DIF_SUBR_DIRNAME: + case DIF_SUBR_BASENAME: { + char *dest = (char *)mstate->dtms_scratch_ptr; + uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; + uintptr_t src = tupregs[0].dttk_value; + int i, j, len = dtrace_strlen((char *)src, size); + int lastbase = -1, firstbase = -1, lastdir = -1; + int start, end; + + if (!dtrace_canload(src, len + 1, mstate, vstate)) { + regs[rd] = 0; + break; + } + + if (!DTRACE_INSCRATCH(mstate, size)) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + regs[rd] = 0; + break; + } + + /* + * The basename and dirname for a zero-length string is + * defined to be "." + */ + if (len == 0) { + len = 1; + src = (uintptr_t)"."; + } + + /* + * Start from the back of the string, moving back toward the + * front until we see a character that isn't a slash. That + * character is the last character in the basename. + */ + for (i = len - 1; i >= 0; i--) { + if (dtrace_load8(src + i) != '/') + break; + } + + if (i >= 0) + lastbase = i; + + /* + * Starting from the last character in the basename, move + * towards the front until we find a slash. The character + * that we processed immediately before that is the first + * character in the basename. + */ + for (; i >= 0; i--) { + if (dtrace_load8(src + i) == '/') + break; + } + + if (i >= 0) + firstbase = i + 1; + + /* + * Now keep going until we find a non-slash character. That + * character is the last character in the dirname. + */ + for (; i >= 0; i--) { + if (dtrace_load8(src + i) != '/') + break; + } + + if (i >= 0) + lastdir = i; + + ASSERT(!(lastbase == -1 && firstbase != -1)); + ASSERT(!(firstbase == -1 && lastdir != -1)); + + if (lastbase == -1) { + /* + * We didn't find a non-slash character. We know that + * the length is non-zero, so the whole string must be + * slashes. In either the dirname or the basename + * case, we return '/'. + */ + ASSERT(firstbase == -1); + firstbase = lastbase = lastdir = 0; + } + + if (firstbase == -1) { + /* + * The entire string consists only of a basename + * component. If we're looking for dirname, we need + * to change our string to be just "."; if we're + * looking for a basename, we'll just set the first + * character of the basename to be 0. + */ + if (subr == DIF_SUBR_DIRNAME) { + ASSERT(lastdir == -1); + src = (uintptr_t)"."; + lastdir = 0; + } else { + firstbase = 0; + } + } + + if (subr == DIF_SUBR_DIRNAME) { + if (lastdir == -1) { + /* + * We know that we have a slash in the name -- + * or lastdir would be set to 0, above. And + * because lastdir is -1, we know that this + * slash must be the first character. (That + * is, the full string must be of the form + * "/basename".) In this case, the last + * character of the directory name is 0. + */ + lastdir = 0; + } + + start = 0; + end = lastdir; + } else { + ASSERT(subr == DIF_SUBR_BASENAME); + ASSERT(firstbase != -1 && lastbase != -1); + start = firstbase; + end = lastbase; + } + + for (i = start, j = 0; i <= end && j < size - 1; i++, j++) + dest[j] = dtrace_load8(src + i); + + dest[j] = '\0'; + regs[rd] = (uintptr_t)dest; + mstate->dtms_scratch_ptr += size; + break; + } + + case DIF_SUBR_GETF: { + uintptr_t fd = tupregs[0].dttk_value; + struct filedesc *fdp; + file_t *fp; + + if (!dtrace_priv_proc(state)) { + regs[rd] = 0; + break; + } + fdp = curproc->p_fd; + FILEDESC_SLOCK(fdp); + fp = fget_locked(fdp, fd); + mstate->dtms_getf = fp; + regs[rd] = (uintptr_t)fp; + FILEDESC_SUNLOCK(fdp); + break; + } + + case DIF_SUBR_CLEANPATH: { + char *dest = (char *)mstate->dtms_scratch_ptr, c; + uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; + uintptr_t src = tupregs[0].dttk_value; + size_t lim; + int i = 0, j = 0; +#ifdef illumos + zone_t *z; +#endif + + if (!dtrace_strcanload(src, size, &lim, mstate, vstate)) { + regs[rd] = 0; + break; + } + + if (!DTRACE_INSCRATCH(mstate, size)) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + regs[rd] = 0; + break; + } + + /* + * Move forward, loading each character. + */ + do { + c = (i >= lim) ? '\0' : dtrace_load8(src + i++); +next: + if (j + 5 >= size) /* 5 = strlen("/..c\0") */ + break; + + if (c != '/') { + dest[j++] = c; + continue; + } + + c = (i >= lim) ? '\0' : dtrace_load8(src + i++); + + if (c == '/') { + /* + * We have two slashes -- we can just advance + * to the next character. + */ + goto next; + } + + if (c != '.') { + /* + * This is not "." and it's not ".." -- we can + * just store the "/" and this character and + * drive on. + */ + dest[j++] = '/'; + dest[j++] = c; + continue; + } + + c = (i >= lim) ? '\0' : dtrace_load8(src + i++); + + if (c == '/') { + /* + * This is a "/./" component. We're not going + * to store anything in the destination buffer; + * we're just going to go to the next component. + */ + goto next; + } + + if (c != '.') { + /* + * This is not ".." -- we can just store the + * "/." and this character and continue + * processing. + */ + dest[j++] = '/'; + dest[j++] = '.'; + dest[j++] = c; + continue; + } + + c = (i >= lim) ? '\0' : dtrace_load8(src + i++); + + if (c != '/' && c != '\0') { + /* + * This is not ".." -- it's "..[mumble]". + * We'll store the "/.." and this character + * and continue processing. + */ + dest[j++] = '/'; + dest[j++] = '.'; + dest[j++] = '.'; + dest[j++] = c; + continue; + } + + /* + * This is "/../" or "/..\0". We need to back up + * our destination pointer until we find a "/". + */ + i--; + while (j != 0 && dest[--j] != '/') + continue; + + if (c == '\0') + dest[++j] = '/'; + } while (c != '\0'); + + dest[j] = '\0'; + +#ifdef illumos + if (mstate->dtms_getf != NULL && + !(mstate->dtms_access & DTRACE_ACCESS_KERNEL) && + (z = state->dts_cred.dcr_cred->cr_zone) != kcred->cr_zone) { + /* + * If we've done a getf() as a part of this ECB and we + * don't have kernel access (and we're not in the global + * zone), check if the path we cleaned up begins with + * the zone's root path, and trim it off if so. Note + * that this is an output cleanliness issue, not a + * security issue: knowing one's zone root path does + * not enable privilege escalation. + */ + if (strstr(dest, z->zone_rootpath) == dest) + dest += strlen(z->zone_rootpath) - 1; + } +#endif + + regs[rd] = (uintptr_t)dest; + mstate->dtms_scratch_ptr += size; + break; + } + + case DIF_SUBR_INET_NTOA: + case DIF_SUBR_INET_NTOA6: + case DIF_SUBR_INET_NTOP: { + size_t size; + int af, argi, i; + char *base, *end; + + if (subr == DIF_SUBR_INET_NTOP) { + af = (int)tupregs[0].dttk_value; + argi = 1; + } else { + af = subr == DIF_SUBR_INET_NTOA ? AF_INET: AF_INET6; + argi = 0; + } + + if (af == AF_INET) { + ipaddr_t ip4; + uint8_t *ptr8, val; + + if (!dtrace_canload(tupregs[argi].dttk_value, + sizeof (ipaddr_t), mstate, vstate)) { + regs[rd] = 0; + break; + } + + /* + * Safely load the IPv4 address. + */ + ip4 = dtrace_load32(tupregs[argi].dttk_value); + + /* + * Check an IPv4 string will fit in scratch. + */ + size = INET_ADDRSTRLEN; + if (!DTRACE_INSCRATCH(mstate, size)) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + regs[rd] = 0; + break; + } + base = (char *)mstate->dtms_scratch_ptr; + end = (char *)mstate->dtms_scratch_ptr + size - 1; + + /* + * Stringify as a dotted decimal quad. + */ + *end-- = '\0'; + ptr8 = (uint8_t *)&ip4; + for (i = 3; i >= 0; i--) { + val = ptr8[i]; + + if (val == 0) { + *end-- = '0'; + } else { + for (; val; val /= 10) { + *end-- = '0' + (val % 10); + } + } + + if (i > 0) + *end-- = '.'; + } + ASSERT(end + 1 >= base); + + } else if (af == AF_INET6) { + struct in6_addr ip6; + int firstzero, tryzero, numzero, v6end; + uint16_t val; + const char digits[] = "0123456789abcdef"; + + /* + * Stringify using RFC 1884 convention 2 - 16 bit + * hexadecimal values with a zero-run compression. + * Lower case hexadecimal digits are used. + * eg, fe80::214:4fff:fe0b:76c8. + * The IPv4 embedded form is returned for inet_ntop, + * just the IPv4 string is returned for inet_ntoa6. + */ + + if (!dtrace_canload(tupregs[argi].dttk_value, + sizeof (struct in6_addr), mstate, vstate)) { + regs[rd] = 0; + break; + } + + /* + * Safely load the IPv6 address. + */ + dtrace_bcopy( + (void *)(uintptr_t)tupregs[argi].dttk_value, + (void *)(uintptr_t)&ip6, sizeof (struct in6_addr)); + + /* + * Check an IPv6 string will fit in scratch. + */ + size = INET6_ADDRSTRLEN; + if (!DTRACE_INSCRATCH(mstate, size)) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + regs[rd] = 0; + break; + } + base = (char *)mstate->dtms_scratch_ptr; + end = (char *)mstate->dtms_scratch_ptr + size - 1; + *end-- = '\0'; + + /* + * Find the longest run of 16 bit zero values + * for the single allowed zero compression - "::". + */ + firstzero = -1; + tryzero = -1; + numzero = 1; + for (i = 0; i < sizeof (struct in6_addr); i++) { +#ifdef illumos + if (ip6._S6_un._S6_u8[i] == 0 && +#else + if (ip6.__u6_addr.__u6_addr8[i] == 0 && +#endif + tryzero == -1 && i % 2 == 0) { + tryzero = i; + continue; + } + + if (tryzero != -1 && +#ifdef illumos + (ip6._S6_un._S6_u8[i] != 0 || +#else + (ip6.__u6_addr.__u6_addr8[i] != 0 || +#endif + i == sizeof (struct in6_addr) - 1)) { + + if (i - tryzero <= numzero) { + tryzero = -1; + continue; + } + + firstzero = tryzero; + numzero = i - i % 2 - tryzero; + tryzero = -1; + +#ifdef illumos + if (ip6._S6_un._S6_u8[i] == 0 && +#else + if (ip6.__u6_addr.__u6_addr8[i] == 0 && +#endif + i == sizeof (struct in6_addr) - 1) + numzero += 2; + } + } + ASSERT(firstzero + numzero <= sizeof (struct in6_addr)); + + /* + * Check for an IPv4 embedded address. + */ + v6end = sizeof (struct in6_addr) - 2; + if (IN6_IS_ADDR_V4MAPPED(&ip6) || + IN6_IS_ADDR_V4COMPAT(&ip6)) { + for (i = sizeof (struct in6_addr) - 1; + i >= DTRACE_V4MAPPED_OFFSET; i--) { + ASSERT(end >= base); + +#ifdef illumos + val = ip6._S6_un._S6_u8[i]; +#else + val = ip6.__u6_addr.__u6_addr8[i]; +#endif + + if (val == 0) { + *end-- = '0'; + } else { + for (; val; val /= 10) { + *end-- = '0' + val % 10; + } + } + + if (i > DTRACE_V4MAPPED_OFFSET) + *end-- = '.'; + } + + if (subr == DIF_SUBR_INET_NTOA6) + goto inetout; + + /* + * Set v6end to skip the IPv4 address that + * we have already stringified. + */ + v6end = 10; + } + + /* + * Build the IPv6 string by working through the + * address in reverse. + */ + for (i = v6end; i >= 0; i -= 2) { + ASSERT(end >= base); + + if (i == firstzero + numzero - 2) { + *end-- = ':'; + *end-- = ':'; + i -= numzero - 2; + continue; + } + + if (i < 14 && i != firstzero - 2) + *end-- = ':'; + +#ifdef illumos + val = (ip6._S6_un._S6_u8[i] << 8) + + ip6._S6_un._S6_u8[i + 1]; +#else + val = (ip6.__u6_addr.__u6_addr8[i] << 8) + + ip6.__u6_addr.__u6_addr8[i + 1]; +#endif + + if (val == 0) { + *end-- = '0'; + } else { + for (; val; val /= 16) { + *end-- = digits[val % 16]; + } + } + } + ASSERT(end + 1 >= base); + + } else { + /* + * The user didn't use AH_INET or AH_INET6. + */ + DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); + regs[rd] = 0; + break; + } + +inetout: regs[rd] = (uintptr_t)end + 1; + mstate->dtms_scratch_ptr += size; + break; + } + + case DIF_SUBR_MEMREF: { + uintptr_t size = 2 * sizeof(uintptr_t); + uintptr_t *memref = (uintptr_t *) P2ROUNDUP(mstate->dtms_scratch_ptr, sizeof(uintptr_t)); + size_t scratch_size = ((uintptr_t) memref - mstate->dtms_scratch_ptr) + size; + + /* address and length */ + memref[0] = tupregs[0].dttk_value; + memref[1] = tupregs[1].dttk_value; + + regs[rd] = (uintptr_t) memref; + mstate->dtms_scratch_ptr += scratch_size; + break; + } + +#ifndef illumos + case DIF_SUBR_MEMSTR: { + char *str = (char *)mstate->dtms_scratch_ptr; + uintptr_t mem = tupregs[0].dttk_value; + char c = tupregs[1].dttk_value; + size_t size = tupregs[2].dttk_value; + uint8_t n; + int i; + + regs[rd] = 0; + + if (size == 0) + break; + + if (!dtrace_canload(mem, size - 1, mstate, vstate)) + break; + + if (!DTRACE_INSCRATCH(mstate, size)) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + break; + } + + if (dtrace_memstr_max != 0 && size > dtrace_memstr_max) { + *flags |= CPU_DTRACE_ILLOP; + break; + } + + for (i = 0; i < size - 1; i++) { + n = dtrace_load8(mem++); + str[i] = (n == 0) ? c : n; + } + str[size - 1] = 0; + + regs[rd] = (uintptr_t)str; + mstate->dtms_scratch_ptr += size; + break; + } +#endif + } +} + +/* + * Emulate the execution of DTrace IR instructions specified by the given + * DIF object. This function is deliberately void of assertions as all of + * the necessary checks are handled by a call to dtrace_difo_validate(). + */ +static uint64_t +dtrace_dif_emulate(dtrace_difo_t *difo, dtrace_mstate_t *mstate, + dtrace_vstate_t *vstate, dtrace_state_t *state) +{ + const dif_instr_t *text = difo->dtdo_buf; + const uint_t textlen = difo->dtdo_len; + const char *strtab = difo->dtdo_strtab; + const uint64_t *inttab = difo->dtdo_inttab; + + uint64_t rval = 0; + dtrace_statvar_t *svar; + dtrace_dstate_t *dstate = &vstate->dtvs_dynvars; + dtrace_difv_t *v; + volatile uint16_t *flags = &cpu_core[curcpu].cpuc_dtrace_flags; + volatile uintptr_t *illval = &cpu_core[curcpu].cpuc_dtrace_illval; + + dtrace_key_t tupregs[DIF_DTR_NREGS + 2]; /* +2 for thread and id */ + uint64_t regs[DIF_DIR_NREGS]; + uint64_t *tmp; + + uint8_t cc_n = 0, cc_z = 0, cc_v = 0, cc_c = 0; + int64_t cc_r; + uint_t pc = 0, id, opc = 0; + uint8_t ttop = 0; + dif_instr_t instr; + uint_t r1, r2, rd; + + /* + * We stash the current DIF object into the machine state: we need it + * for subsequent access checking. + */ + mstate->dtms_difo = difo; + + regs[DIF_REG_R0] = 0; /* %r0 is fixed at zero */ + + while (pc < textlen && !(*flags & CPU_DTRACE_FAULT)) { + opc = pc; + + instr = text[pc++]; + r1 = DIF_INSTR_R1(instr); + r2 = DIF_INSTR_R2(instr); + rd = DIF_INSTR_RD(instr); + + switch (DIF_INSTR_OP(instr)) { + case DIF_OP_OR: + regs[rd] = regs[r1] | regs[r2]; + break; + case DIF_OP_XOR: + regs[rd] = regs[r1] ^ regs[r2]; + break; + case DIF_OP_AND: + regs[rd] = regs[r1] & regs[r2]; + break; + case DIF_OP_SLL: + regs[rd] = regs[r1] << regs[r2]; + break; + case DIF_OP_SRL: + regs[rd] = regs[r1] >> regs[r2]; + break; + case DIF_OP_SUB: + regs[rd] = regs[r1] - regs[r2]; + break; + case DIF_OP_ADD: + regs[rd] = regs[r1] + regs[r2]; + break; + case DIF_OP_MUL: + regs[rd] = regs[r1] * regs[r2]; + break; + case DIF_OP_SDIV: + if (regs[r2] == 0) { + regs[rd] = 0; + *flags |= CPU_DTRACE_DIVZERO; + } else { + regs[rd] = (int64_t)regs[r1] / + (int64_t)regs[r2]; + } + break; + + case DIF_OP_UDIV: + if (regs[r2] == 0) { + regs[rd] = 0; + *flags |= CPU_DTRACE_DIVZERO; + } else { + regs[rd] = regs[r1] / regs[r2]; + } + break; + + case DIF_OP_SREM: + if (regs[r2] == 0) { + regs[rd] = 0; + *flags |= CPU_DTRACE_DIVZERO; + } else { + regs[rd] = (int64_t)regs[r1] % + (int64_t)regs[r2]; + } + break; + + case DIF_OP_UREM: + if (regs[r2] == 0) { + regs[rd] = 0; + *flags |= CPU_DTRACE_DIVZERO; + } else { + regs[rd] = regs[r1] % regs[r2]; + } + break; + + case DIF_OP_NOT: + regs[rd] = ~regs[r1]; + break; + case DIF_OP_MOV: + regs[rd] = regs[r1]; + break; + case DIF_OP_CMP: + cc_r = regs[r1] - regs[r2]; + cc_n = cc_r < 0; + cc_z = cc_r == 0; + cc_v = 0; + cc_c = regs[r1] < regs[r2]; + break; + case DIF_OP_TST: + cc_n = cc_v = cc_c = 0; + cc_z = regs[r1] == 0; + break; + case DIF_OP_BA: + pc = DIF_INSTR_LABEL(instr); + break; + case DIF_OP_BE: + if (cc_z) + pc = DIF_INSTR_LABEL(instr); + break; + case DIF_OP_BNE: + if (cc_z == 0) + pc = DIF_INSTR_LABEL(instr); + break; + case DIF_OP_BG: + if ((cc_z | (cc_n ^ cc_v)) == 0) + pc = DIF_INSTR_LABEL(instr); + break; + case DIF_OP_BGU: + if ((cc_c | cc_z) == 0) + pc = DIF_INSTR_LABEL(instr); + break; + case DIF_OP_BGE: + if ((cc_n ^ cc_v) == 0) + pc = DIF_INSTR_LABEL(instr); + break; + case DIF_OP_BGEU: + if (cc_c == 0) + pc = DIF_INSTR_LABEL(instr); + break; + case DIF_OP_BL: + if (cc_n ^ cc_v) + pc = DIF_INSTR_LABEL(instr); + break; + case DIF_OP_BLU: + if (cc_c) + pc = DIF_INSTR_LABEL(instr); + break; + case DIF_OP_BLE: + if (cc_z | (cc_n ^ cc_v)) + pc = DIF_INSTR_LABEL(instr); + break; + case DIF_OP_BLEU: + if (cc_c | cc_z) + pc = DIF_INSTR_LABEL(instr); + break; + case DIF_OP_RLDSB: + if (!dtrace_canload(regs[r1], 1, mstate, vstate)) + break; + /*FALLTHROUGH*/ + case DIF_OP_LDSB: + regs[rd] = (int8_t)dtrace_load8(regs[r1]); + break; + case DIF_OP_RLDSH: + if (!dtrace_canload(regs[r1], 2, mstate, vstate)) + break; + /*FALLTHROUGH*/ + case DIF_OP_LDSH: + regs[rd] = (int16_t)dtrace_load16(regs[r1]); + break; + case DIF_OP_RLDSW: + if (!dtrace_canload(regs[r1], 4, mstate, vstate)) + break; + /*FALLTHROUGH*/ + case DIF_OP_LDSW: + regs[rd] = (int32_t)dtrace_load32(regs[r1]); + break; + case DIF_OP_RLDUB: + if (!dtrace_canload(regs[r1], 1, mstate, vstate)) + break; + /*FALLTHROUGH*/ + case DIF_OP_LDUB: + regs[rd] = dtrace_load8(regs[r1]); + break; + case DIF_OP_RLDUH: + if (!dtrace_canload(regs[r1], 2, mstate, vstate)) + break; + /*FALLTHROUGH*/ + case DIF_OP_LDUH: + regs[rd] = dtrace_load16(regs[r1]); + break; + case DIF_OP_RLDUW: + if (!dtrace_canload(regs[r1], 4, mstate, vstate)) + break; + /*FALLTHROUGH*/ + case DIF_OP_LDUW: + regs[rd] = dtrace_load32(regs[r1]); + break; + case DIF_OP_RLDX: + if (!dtrace_canload(regs[r1], 8, mstate, vstate)) + break; + /*FALLTHROUGH*/ + case DIF_OP_LDX: + regs[rd] = dtrace_load64(regs[r1]); + break; + case DIF_OP_ULDSB: + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + regs[rd] = (int8_t) + dtrace_fuword8((void *)(uintptr_t)regs[r1]); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + break; + case DIF_OP_ULDSH: + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + regs[rd] = (int16_t) + dtrace_fuword16((void *)(uintptr_t)regs[r1]); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + break; + case DIF_OP_ULDSW: + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + regs[rd] = (int32_t) + dtrace_fuword32((void *)(uintptr_t)regs[r1]); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + break; + case DIF_OP_ULDUB: + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + regs[rd] = + dtrace_fuword8((void *)(uintptr_t)regs[r1]); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + break; + case DIF_OP_ULDUH: + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + regs[rd] = + dtrace_fuword16((void *)(uintptr_t)regs[r1]); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + break; + case DIF_OP_ULDUW: + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + regs[rd] = + dtrace_fuword32((void *)(uintptr_t)regs[r1]); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + break; + case DIF_OP_ULDX: + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + regs[rd] = + dtrace_fuword64((void *)(uintptr_t)regs[r1]); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + break; + case DIF_OP_RET: + rval = regs[rd]; + pc = textlen; + break; + case DIF_OP_NOP: + break; + case DIF_OP_SETX: + regs[rd] = inttab[DIF_INSTR_INTEGER(instr)]; + break; + case DIF_OP_SETS: + regs[rd] = (uint64_t)(uintptr_t) + (strtab + DIF_INSTR_STRING(instr)); + break; + case DIF_OP_SCMP: { + size_t sz = state->dts_options[DTRACEOPT_STRSIZE]; + uintptr_t s1 = regs[r1]; + uintptr_t s2 = regs[r2]; + size_t lim1, lim2; + + if (s1 != 0 && + !dtrace_strcanload(s1, sz, &lim1, mstate, vstate)) + break; + if (s2 != 0 && + !dtrace_strcanload(s2, sz, &lim2, mstate, vstate)) + break; + + cc_r = dtrace_strncmp((char *)s1, (char *)s2, + MIN(lim1, lim2)); + + cc_n = cc_r < 0; + cc_z = cc_r == 0; + cc_v = cc_c = 0; + break; + } + case DIF_OP_LDGA: + regs[rd] = dtrace_dif_variable(mstate, state, + r1, regs[r2]); + break; + case DIF_OP_LDGS: + id = DIF_INSTR_VAR(instr); + + if (id >= DIF_VAR_OTHER_UBASE) { + uintptr_t a; + + id -= DIF_VAR_OTHER_UBASE; + svar = vstate->dtvs_globals[id]; + ASSERT(svar != NULL); + v = &svar->dtsv_var; + + if (!(v->dtdv_type.dtdt_flags & DIF_TF_BYREF)) { + regs[rd] = svar->dtsv_data; + break; + } + + a = (uintptr_t)svar->dtsv_data; + + if (*(uint8_t *)a == UINT8_MAX) { + /* + * If the 0th byte is set to UINT8_MAX + * then this is to be treated as a + * reference to a NULL variable. + */ + regs[rd] = 0; + } else { + regs[rd] = a + sizeof (uint64_t); + } + + break; + } + + regs[rd] = dtrace_dif_variable(mstate, state, id, 0); + break; + + case DIF_OP_STGS: + id = DIF_INSTR_VAR(instr); + + ASSERT(id >= DIF_VAR_OTHER_UBASE); + id -= DIF_VAR_OTHER_UBASE; + + VERIFY(id < vstate->dtvs_nglobals); + svar = vstate->dtvs_globals[id]; + ASSERT(svar != NULL); + v = &svar->dtsv_var; + + if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) { + uintptr_t a = (uintptr_t)svar->dtsv_data; + size_t lim; + + ASSERT(a != 0); + ASSERT(svar->dtsv_size != 0); + + if (regs[rd] == 0) { + *(uint8_t *)a = UINT8_MAX; + break; + } else { + *(uint8_t *)a = 0; + a += sizeof (uint64_t); + } + if (!dtrace_vcanload( + (void *)(uintptr_t)regs[rd], &v->dtdv_type, + &lim, mstate, vstate)) + break; + + dtrace_vcopy((void *)(uintptr_t)regs[rd], + (void *)a, &v->dtdv_type, lim); + break; + } + + svar->dtsv_data = regs[rd]; + break; + + case DIF_OP_LDTA: + /* + * There are no DTrace built-in thread-local arrays at + * present. This opcode is saved for future work. + */ + *flags |= CPU_DTRACE_ILLOP; + regs[rd] = 0; + break; + + case DIF_OP_LDLS: + id = DIF_INSTR_VAR(instr); + + if (id < DIF_VAR_OTHER_UBASE) { + /* + * For now, this has no meaning. + */ + regs[rd] = 0; + break; + } + + id -= DIF_VAR_OTHER_UBASE; + + ASSERT(id < vstate->dtvs_nlocals); + ASSERT(vstate->dtvs_locals != NULL); + + svar = vstate->dtvs_locals[id]; + ASSERT(svar != NULL); + v = &svar->dtsv_var; + + if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) { + uintptr_t a = (uintptr_t)svar->dtsv_data; + size_t sz = v->dtdv_type.dtdt_size; + size_t lim; + + sz += sizeof (uint64_t); + ASSERT(svar->dtsv_size == NCPU * sz); + a += curcpu * sz; + + if (*(uint8_t *)a == UINT8_MAX) { + /* + * If the 0th byte is set to UINT8_MAX + * then this is to be treated as a + * reference to a NULL variable. + */ + regs[rd] = 0; + } else { + regs[rd] = a + sizeof (uint64_t); + } + + break; + } + + ASSERT(svar->dtsv_size == NCPU * sizeof (uint64_t)); + tmp = (uint64_t *)(uintptr_t)svar->dtsv_data; + regs[rd] = tmp[curcpu]; + break; + + case DIF_OP_STLS: + id = DIF_INSTR_VAR(instr); + + ASSERT(id >= DIF_VAR_OTHER_UBASE); + id -= DIF_VAR_OTHER_UBASE; + VERIFY(id < vstate->dtvs_nlocals); + + ASSERT(vstate->dtvs_locals != NULL); + svar = vstate->dtvs_locals[id]; + ASSERT(svar != NULL); + v = &svar->dtsv_var; + + if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) { + uintptr_t a = (uintptr_t)svar->dtsv_data; + size_t sz = v->dtdv_type.dtdt_size; + size_t lim; + + sz += sizeof (uint64_t); + ASSERT(svar->dtsv_size == NCPU * sz); + a += curcpu * sz; + + if (regs[rd] == 0) { + *(uint8_t *)a = UINT8_MAX; + break; + } else { + *(uint8_t *)a = 0; + a += sizeof (uint64_t); + } + + if (!dtrace_vcanload( + (void *)(uintptr_t)regs[rd], &v->dtdv_type, + &lim, mstate, vstate)) + break; + + dtrace_vcopy((void *)(uintptr_t)regs[rd], + (void *)a, &v->dtdv_type, lim); + break; + } + + ASSERT(svar->dtsv_size == NCPU * sizeof (uint64_t)); + tmp = (uint64_t *)(uintptr_t)svar->dtsv_data; + tmp[curcpu] = regs[rd]; + break; + + case DIF_OP_LDTS: { + dtrace_dynvar_t *dvar; + dtrace_key_t *key; + + id = DIF_INSTR_VAR(instr); + ASSERT(id >= DIF_VAR_OTHER_UBASE); + id -= DIF_VAR_OTHER_UBASE; + v = &vstate->dtvs_tlocals[id]; + + key = &tupregs[DIF_DTR_NREGS]; + key[0].dttk_value = (uint64_t)id; + key[0].dttk_size = 0; + DTRACE_TLS_THRKEY(key[1].dttk_value); + key[1].dttk_size = 0; + + dvar = dtrace_dynvar(dstate, 2, key, + sizeof (uint64_t), DTRACE_DYNVAR_NOALLOC, + mstate, vstate); + + if (dvar == NULL) { + regs[rd] = 0; + break; + } + + if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) { + regs[rd] = (uint64_t)(uintptr_t)dvar->dtdv_data; + } else { + regs[rd] = *((uint64_t *)dvar->dtdv_data); + } + + break; + } + + case DIF_OP_STTS: { + dtrace_dynvar_t *dvar; + dtrace_key_t *key; + + id = DIF_INSTR_VAR(instr); + ASSERT(id >= DIF_VAR_OTHER_UBASE); + id -= DIF_VAR_OTHER_UBASE; + VERIFY(id < vstate->dtvs_ntlocals); + + key = &tupregs[DIF_DTR_NREGS]; + key[0].dttk_value = (uint64_t)id; + key[0].dttk_size = 0; + DTRACE_TLS_THRKEY(key[1].dttk_value); + key[1].dttk_size = 0; + v = &vstate->dtvs_tlocals[id]; + + dvar = dtrace_dynvar(dstate, 2, key, + v->dtdv_type.dtdt_size > sizeof (uint64_t) ? + v->dtdv_type.dtdt_size : sizeof (uint64_t), + regs[rd] ? DTRACE_DYNVAR_ALLOC : + DTRACE_DYNVAR_DEALLOC, mstate, vstate); + + /* + * Given that we're storing to thread-local data, + * we need to flush our predicate cache. + */ + curthread->t_predcache = 0; + + if (dvar == NULL) + break; + + if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) { + size_t lim; + + if (!dtrace_vcanload( + (void *)(uintptr_t)regs[rd], + &v->dtdv_type, &lim, mstate, vstate)) + break; + + dtrace_vcopy((void *)(uintptr_t)regs[rd], + dvar->dtdv_data, &v->dtdv_type, lim); + } else { + *((uint64_t *)dvar->dtdv_data) = regs[rd]; + } + + break; + } + + case DIF_OP_SRA: + regs[rd] = (int64_t)regs[r1] >> regs[r2]; + break; + + case DIF_OP_CALL: + dtrace_dif_subr(DIF_INSTR_SUBR(instr), rd, + regs, tupregs, ttop, mstate, state); + break; + + case DIF_OP_PUSHTR: + if (ttop == DIF_DTR_NREGS) { + *flags |= CPU_DTRACE_TUPOFLOW; + break; + } + + if (r1 == DIF_TYPE_STRING) { + /* + * If this is a string type and the size is 0, + * we'll use the system-wide default string + * size. Note that we are _not_ looking at + * the value of the DTRACEOPT_STRSIZE option; + * had this been set, we would expect to have + * a non-zero size value in the "pushtr". + */ + tupregs[ttop].dttk_size = + dtrace_strlen((char *)(uintptr_t)regs[rd], + regs[r2] ? regs[r2] : + dtrace_strsize_default) + 1; + } else { + if (regs[r2] > LONG_MAX) { + *flags |= CPU_DTRACE_ILLOP; + break; + } + + tupregs[ttop].dttk_size = regs[r2]; + } + + tupregs[ttop++].dttk_value = regs[rd]; + break; + + case DIF_OP_PUSHTV: + if (ttop == DIF_DTR_NREGS) { + *flags |= CPU_DTRACE_TUPOFLOW; + break; + } + + tupregs[ttop].dttk_value = regs[rd]; + tupregs[ttop++].dttk_size = 0; + break; + + case DIF_OP_POPTS: + if (ttop != 0) + ttop--; + break; + + case DIF_OP_FLUSHTS: + ttop = 0; + break; + + case DIF_OP_LDGAA: + case DIF_OP_LDTAA: { + dtrace_dynvar_t *dvar; + dtrace_key_t *key = tupregs; + uint_t nkeys = ttop; + + id = DIF_INSTR_VAR(instr); + ASSERT(id >= DIF_VAR_OTHER_UBASE); + id -= DIF_VAR_OTHER_UBASE; + + key[nkeys].dttk_value = (uint64_t)id; + key[nkeys++].dttk_size = 0; + + if (DIF_INSTR_OP(instr) == DIF_OP_LDTAA) { + DTRACE_TLS_THRKEY(key[nkeys].dttk_value); + key[nkeys++].dttk_size = 0; + VERIFY(id < vstate->dtvs_ntlocals); + v = &vstate->dtvs_tlocals[id]; + } else { + VERIFY(id < vstate->dtvs_nglobals); + v = &vstate->dtvs_globals[id]->dtsv_var; + } + + dvar = dtrace_dynvar(dstate, nkeys, key, + v->dtdv_type.dtdt_size > sizeof (uint64_t) ? + v->dtdv_type.dtdt_size : sizeof (uint64_t), + DTRACE_DYNVAR_NOALLOC, mstate, vstate); + + if (dvar == NULL) { + regs[rd] = 0; + break; + } + + if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) { + regs[rd] = (uint64_t)(uintptr_t)dvar->dtdv_data; + } else { + regs[rd] = *((uint64_t *)dvar->dtdv_data); + } + + break; + } + + case DIF_OP_STGAA: + case DIF_OP_STTAA: { + dtrace_dynvar_t *dvar; + dtrace_key_t *key = tupregs; + uint_t nkeys = ttop; + + id = DIF_INSTR_VAR(instr); + ASSERT(id >= DIF_VAR_OTHER_UBASE); + id -= DIF_VAR_OTHER_UBASE; + + key[nkeys].dttk_value = (uint64_t)id; + key[nkeys++].dttk_size = 0; + + if (DIF_INSTR_OP(instr) == DIF_OP_STTAA) { + DTRACE_TLS_THRKEY(key[nkeys].dttk_value); + key[nkeys++].dttk_size = 0; + VERIFY(id < vstate->dtvs_ntlocals); + v = &vstate->dtvs_tlocals[id]; + } else { + VERIFY(id < vstate->dtvs_nglobals); + v = &vstate->dtvs_globals[id]->dtsv_var; + } + + dvar = dtrace_dynvar(dstate, nkeys, key, + v->dtdv_type.dtdt_size > sizeof (uint64_t) ? + v->dtdv_type.dtdt_size : sizeof (uint64_t), + regs[rd] ? DTRACE_DYNVAR_ALLOC : + DTRACE_DYNVAR_DEALLOC, mstate, vstate); + + if (dvar == NULL) + break; + + if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) { + size_t lim; + + if (!dtrace_vcanload( + (void *)(uintptr_t)regs[rd], &v->dtdv_type, + &lim, mstate, vstate)) + break; + + dtrace_vcopy((void *)(uintptr_t)regs[rd], + dvar->dtdv_data, &v->dtdv_type, lim); + } else { + *((uint64_t *)dvar->dtdv_data) = regs[rd]; + } + + break; + } + + case DIF_OP_ALLOCS: { + uintptr_t ptr = P2ROUNDUP(mstate->dtms_scratch_ptr, 8); + size_t size = ptr - mstate->dtms_scratch_ptr + regs[r1]; + + /* + * Rounding up the user allocation size could have + * overflowed large, bogus allocations (like -1ULL) to + * 0. + */ + if (size < regs[r1] || + !DTRACE_INSCRATCH(mstate, size)) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + regs[rd] = 0; + break; + } + + dtrace_bzero((void *) mstate->dtms_scratch_ptr, size); + mstate->dtms_scratch_ptr += size; + regs[rd] = ptr; + break; + } + + case DIF_OP_COPYS: + if (!dtrace_canstore(regs[rd], regs[r2], + mstate, vstate)) { + *flags |= CPU_DTRACE_BADADDR; + *illval = regs[rd]; + break; + } + + if (!dtrace_canload(regs[r1], regs[r2], mstate, vstate)) + break; + + dtrace_bcopy((void *)(uintptr_t)regs[r1], + (void *)(uintptr_t)regs[rd], (size_t)regs[r2]); + break; + + case DIF_OP_STB: + if (!dtrace_canstore(regs[rd], 1, mstate, vstate)) { + *flags |= CPU_DTRACE_BADADDR; + *illval = regs[rd]; + break; + } + *((uint8_t *)(uintptr_t)regs[rd]) = (uint8_t)regs[r1]; + break; + + case DIF_OP_STH: + if (!dtrace_canstore(regs[rd], 2, mstate, vstate)) { + *flags |= CPU_DTRACE_BADADDR; + *illval = regs[rd]; + break; + } + if (regs[rd] & 1) { + *flags |= CPU_DTRACE_BADALIGN; + *illval = regs[rd]; + break; + } + *((uint16_t *)(uintptr_t)regs[rd]) = (uint16_t)regs[r1]; + break; + + case DIF_OP_STW: + if (!dtrace_canstore(regs[rd], 4, mstate, vstate)) { + *flags |= CPU_DTRACE_BADADDR; + *illval = regs[rd]; + break; + } + if (regs[rd] & 3) { + *flags |= CPU_DTRACE_BADALIGN; + *illval = regs[rd]; + break; + } + *((uint32_t *)(uintptr_t)regs[rd]) = (uint32_t)regs[r1]; + break; + + case DIF_OP_STX: + if (!dtrace_canstore(regs[rd], 8, mstate, vstate)) { + *flags |= CPU_DTRACE_BADADDR; + *illval = regs[rd]; + break; + } + if (regs[rd] & 7) { + *flags |= CPU_DTRACE_BADALIGN; + *illval = regs[rd]; + break; + } + *((uint64_t *)(uintptr_t)regs[rd]) = regs[r1]; + break; + } + } + + if (!(*flags & CPU_DTRACE_FAULT)) + return (rval); + + mstate->dtms_fltoffs = opc * sizeof (dif_instr_t); + mstate->dtms_present |= DTRACE_MSTATE_FLTOFFS; + + return (0); +} + +static void +dtrace_action_breakpoint(dtrace_ecb_t *ecb) +{ + dtrace_probe_t *probe = ecb->dte_probe; + dtrace_provider_t *prov = probe->dtpr_provider; + char c[DTRACE_FULLNAMELEN + 80], *str; + char *msg = "dtrace: breakpoint action at probe "; + char *ecbmsg = " (ecb "; + uintptr_t mask = (0xf << (sizeof (uintptr_t) * NBBY / 4)); + uintptr_t val = (uintptr_t)ecb; + int shift = (sizeof (uintptr_t) * NBBY) - 4, i = 0; + + if (dtrace_destructive_disallow) + return; + + /* + * It's impossible to be taking action on the NULL probe. + */ + ASSERT(probe != NULL); + + /* + * This is a poor man's (destitute man's?) sprintf(): we want to + * print the provider name, module name, function name and name of + * the probe, along with the hex address of the ECB with the breakpoint + * action -- all of which we must place in the character buffer by + * hand. + */ + while (*msg != '\0') + c[i++] = *msg++; + + for (str = prov->dtpv_name; *str != '\0'; str++) + c[i++] = *str; + c[i++] = ':'; + + for (str = probe->dtpr_mod; *str != '\0'; str++) + c[i++] = *str; + c[i++] = ':'; + + for (str = probe->dtpr_func; *str != '\0'; str++) + c[i++] = *str; + c[i++] = ':'; + + for (str = probe->dtpr_name; *str != '\0'; str++) + c[i++] = *str; + + while (*ecbmsg != '\0') + c[i++] = *ecbmsg++; + + while (shift >= 0) { + mask = (uintptr_t)0xf << shift; + + if (val >= ((uintptr_t)1 << shift)) + c[i++] = "0123456789abcdef"[(val & mask) >> shift]; + shift -= 4; + } + + c[i++] = ')'; + c[i] = '\0'; + +#ifdef illumos + debug_enter(c); +#else + kdb_enter(KDB_WHY_DTRACE, "breakpoint action"); +#endif +} + +static void +dtrace_action_panic(dtrace_ecb_t *ecb) +{ + dtrace_probe_t *probe = ecb->dte_probe; + + /* + * It's impossible to be taking action on the NULL probe. + */ + ASSERT(probe != NULL); + + if (dtrace_destructive_disallow) + return; + + if (dtrace_panicked != NULL) + return; + + if (dtrace_casptr(&dtrace_panicked, NULL, curthread) != NULL) + return; + + /* + * We won the right to panic. (We want to be sure that only one + * thread calls panic() from dtrace_probe(), and that panic() is + * called exactly once.) + */ + dtrace_panic("dtrace: panic action at probe %s:%s:%s:%s (ecb %p)", + probe->dtpr_provider->dtpv_name, probe->dtpr_mod, + probe->dtpr_func, probe->dtpr_name, (void *)ecb); +} + +static void +dtrace_action_raise(uint64_t sig) +{ + if (dtrace_destructive_disallow) + return; + + if (sig >= NSIG) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); + return; + } + +#ifdef illumos + /* + * raise() has a queue depth of 1 -- we ignore all subsequent + * invocations of the raise() action. + */ + if (curthread->t_dtrace_sig == 0) + curthread->t_dtrace_sig = (uint8_t)sig; + + curthread->t_sig_check = 1; + aston(curthread); +#else + struct proc *p = curproc; + PROC_LOCK(p); + kern_psignal(p, sig); + PROC_UNLOCK(p); +#endif +} + +static void +dtrace_action_stop(void) +{ + if (dtrace_destructive_disallow) + return; + +#ifdef illumos + if (!curthread->t_dtrace_stop) { + curthread->t_dtrace_stop = 1; + curthread->t_sig_check = 1; + aston(curthread); + } +#else + struct proc *p = curproc; + PROC_LOCK(p); + kern_psignal(p, SIGSTOP); + PROC_UNLOCK(p); +#endif +} + +static void +dtrace_action_chill(dtrace_mstate_t *mstate, hrtime_t val) +{ + hrtime_t now; + volatile uint16_t *flags; +#ifdef illumos + cpu_t *cpu = CPU; +#else + cpu_t *cpu = &solaris_cpu[curcpu]; +#endif + + if (dtrace_destructive_disallow) + return; + + flags = (volatile uint16_t *)&cpu_core[curcpu].cpuc_dtrace_flags; + + now = dtrace_gethrtime(); + + if (now - cpu->cpu_dtrace_chillmark > dtrace_chill_interval) { + /* + * We need to advance the mark to the current time. + */ + cpu->cpu_dtrace_chillmark = now; + cpu->cpu_dtrace_chilled = 0; + } + + /* + * Now check to see if the requested chill time would take us over + * the maximum amount of time allowed in the chill interval. (Or + * worse, if the calculation itself induces overflow.) + */ + if (cpu->cpu_dtrace_chilled + val > dtrace_chill_max || + cpu->cpu_dtrace_chilled + val < cpu->cpu_dtrace_chilled) { + *flags |= CPU_DTRACE_ILLOP; + return; + } + + while (dtrace_gethrtime() - now < val) + continue; + + /* + * Normally, we assure that the value of the variable "timestamp" does + * not change within an ECB. The presence of chill() represents an + * exception to this rule, however. + */ + mstate->dtms_present &= ~DTRACE_MSTATE_TIMESTAMP; + cpu->cpu_dtrace_chilled += val; +} + +static void +dtrace_action_ustack(dtrace_mstate_t *mstate, dtrace_state_t *state, + uint64_t *buf, uint64_t arg) +{ + int nframes = DTRACE_USTACK_NFRAMES(arg); + int strsize = DTRACE_USTACK_STRSIZE(arg); + uint64_t *pcs = &buf[1], *fps; + char *str = (char *)&pcs[nframes]; + int size, offs = 0, i, j; + size_t rem; + uintptr_t old = mstate->dtms_scratch_ptr, saved; + uint16_t *flags = &cpu_core[curcpu].cpuc_dtrace_flags; + char *sym; + + /* + * Should be taking a faster path if string space has not been + * allocated. + */ + ASSERT(strsize != 0); + + /* + * We will first allocate some temporary space for the frame pointers. + */ + fps = (uint64_t *)P2ROUNDUP(mstate->dtms_scratch_ptr, 8); + size = (uintptr_t)fps - mstate->dtms_scratch_ptr + + (nframes * sizeof (uint64_t)); + + if (!DTRACE_INSCRATCH(mstate, size)) { + /* + * Not enough room for our frame pointers -- need to indicate + * that we ran out of scratch space. + */ + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); + return; + } + + mstate->dtms_scratch_ptr += size; + saved = mstate->dtms_scratch_ptr; + + /* + * Now get a stack with both program counters and frame pointers. + */ + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + dtrace_getufpstack(buf, fps, nframes + 1); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + + /* + * If that faulted, we're cooked. + */ + if (*flags & CPU_DTRACE_FAULT) + goto out; + + /* + * Now we want to walk up the stack, calling the USTACK helper. For + * each iteration, we restore the scratch pointer. + */ + for (i = 0; i < nframes; i++) { + mstate->dtms_scratch_ptr = saved; + + if (offs >= strsize) + break; + + sym = (char *)(uintptr_t)dtrace_helper( + DTRACE_HELPER_ACTION_USTACK, + mstate, state, pcs[i], fps[i]); + + /* + * If we faulted while running the helper, we're going to + * clear the fault and null out the corresponding string. + */ + if (*flags & CPU_DTRACE_FAULT) { + *flags &= ~CPU_DTRACE_FAULT; + str[offs++] = '\0'; + continue; + } + + if (sym == NULL) { + str[offs++] = '\0'; + continue; + } + + if (!dtrace_strcanload((uintptr_t)sym, strsize, &rem, mstate, + &(state->dts_vstate))) { + str[offs++] = '\0'; + continue; + } + + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + + /* + * Now copy in the string that the helper returned to us. + */ + for (j = 0; offs + j < strsize && j < rem; j++) { + if ((str[offs + j] = sym[j]) == '\0') + break; + } + + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + + offs += j + 1; + } + + if (offs >= strsize) { + /* + * If we didn't have room for all of the strings, we don't + * abort processing -- this needn't be a fatal error -- but we + * still want to increment a counter (dts_stkstroverflows) to + * allow this condition to be warned about. (If this is from + * a jstack() action, it is easily tuned via jstackstrsize.) + */ + dtrace_error(&state->dts_stkstroverflows); + } + + while (offs < strsize) + str[offs++] = '\0'; + +out: + mstate->dtms_scratch_ptr = old; +} + +static void +dtrace_store_by_ref(dtrace_difo_t *dp, caddr_t tomax, size_t size, + size_t *valoffsp, uint64_t *valp, uint64_t end, int intuple, int dtkind) +{ + volatile uint16_t *flags; + uint64_t val = *valp; + size_t valoffs = *valoffsp; + + flags = (volatile uint16_t *)&cpu_core[curcpu].cpuc_dtrace_flags; + ASSERT(dtkind == DIF_TF_BYREF || dtkind == DIF_TF_BYUREF); + + /* + * If this is a string, we're going to only load until we find the zero + * byte -- after which we'll store zero bytes. + */ + if (dp->dtdo_rtype.dtdt_kind == DIF_TYPE_STRING) { + char c = '\0' + 1; + size_t s; + + for (s = 0; s < size; s++) { + if (c != '\0' && dtkind == DIF_TF_BYREF) { + c = dtrace_load8(val++); + } else if (c != '\0' && dtkind == DIF_TF_BYUREF) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + c = dtrace_fuword8((void *)(uintptr_t)val++); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + if (*flags & CPU_DTRACE_FAULT) + break; + } + + DTRACE_STORE(uint8_t, tomax, valoffs++, c); + + if (c == '\0' && intuple) + break; + } + } else { + uint8_t c; + while (valoffs < end) { + if (dtkind == DIF_TF_BYREF) { + c = dtrace_load8(val++); + } else if (dtkind == DIF_TF_BYUREF) { + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + c = dtrace_fuword8((void *)(uintptr_t)val++); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + if (*flags & CPU_DTRACE_FAULT) + break; + } + + DTRACE_STORE(uint8_t, tomax, + valoffs++, c); + } + } + + *valp = val; + *valoffsp = valoffs; +} + +/* + * Disables interrupts and sets the per-thread inprobe flag. When DEBUG is + * defined, we also assert that we are not recursing unless the probe ID is an + * error probe. + */ +static dtrace_icookie_t +dtrace_probe_enter(dtrace_id_t id) +{ + dtrace_icookie_t cookie; + + cookie = dtrace_interrupt_disable(); + + /* + * Unless this is an ERROR probe, we are not allowed to recurse in + * dtrace_probe(). Recursing into DTrace probe usually means that a + * function is instrumented that should not have been instrumented or + * that the ordering guarantee of the records will be violated, + * resulting in unexpected output. If there is an exception to this + * assertion, a new case should be added. + */ + ASSERT(curthread->t_dtrace_inprobe == 0 || + id == dtrace_probeid_error); + curthread->t_dtrace_inprobe = 1; + + return (cookie); +} + +/* + * Clears the per-thread inprobe flag and enables interrupts. + */ +static void +dtrace_probe_exit(dtrace_icookie_t cookie) +{ + + curthread->t_dtrace_inprobe = 0; + dtrace_interrupt_enable(cookie); +} + +/* + * If you're looking for the epicenter of DTrace, you just found it. This + * is the function called by the provider to fire a probe -- from which all + * subsequent probe-context DTrace activity emanates. + */ +void +dtrace_probe(dtrace_id_t id, uintptr_t arg0, uintptr_t arg1, + uintptr_t arg2, uintptr_t arg3, uintptr_t arg4) +{ + processorid_t cpuid; + dtrace_icookie_t cookie; + dtrace_probe_t *probe; + dtrace_mstate_t mstate; + dtrace_ecb_t *ecb; + dtrace_action_t *act; + intptr_t offs; + size_t size; + int vtime, onintr; + volatile uint16_t *flags; + hrtime_t now; + + if (panicstr != NULL) + return; + +#ifdef illumos + /* + * Kick out immediately if this CPU is still being born (in which case + * curthread will be set to -1) or the current thread can't allow + * probes in its current context. + */ + if (((uintptr_t)curthread & 1) || (curthread->t_flag & T_DONTDTRACE)) + return; +#endif + + cookie = dtrace_probe_enter(id); + probe = dtrace_probes[id - 1]; + cpuid = curcpu; + onintr = CPU_ON_INTR(CPU); + + if (!onintr && probe->dtpr_predcache != DTRACE_CACHEIDNONE && + probe->dtpr_predcache == curthread->t_predcache) { + /* + * We have hit in the predicate cache; we know that + * this predicate would evaluate to be false. + */ + dtrace_probe_exit(cookie); + return; + } + +#ifdef illumos + if (panic_quiesce) { +#else + if (panicstr != NULL) { +#endif + /* + * We don't trace anything if we're panicking. + */ + dtrace_probe_exit(cookie); + return; + } + + now = mstate.dtms_timestamp = dtrace_gethrtime(); + mstate.dtms_present = DTRACE_MSTATE_TIMESTAMP; + vtime = dtrace_vtime_references != 0; + + if (vtime && curthread->t_dtrace_start) + curthread->t_dtrace_vtime += now - curthread->t_dtrace_start; + + mstate.dtms_difo = NULL; + mstate.dtms_probe = probe; + mstate.dtms_strtok = 0; + mstate.dtms_arg[0] = arg0; + mstate.dtms_arg[1] = arg1; + mstate.dtms_arg[2] = arg2; + mstate.dtms_arg[3] = arg3; + mstate.dtms_arg[4] = arg4; + + flags = (volatile uint16_t *)&cpu_core[cpuid].cpuc_dtrace_flags; + + for (ecb = probe->dtpr_ecb; ecb != NULL; ecb = ecb->dte_next) { + dtrace_predicate_t *pred = ecb->dte_predicate; + dtrace_state_t *state = ecb->dte_state; + dtrace_buffer_t *buf = &state->dts_buffer[cpuid]; + dtrace_buffer_t *aggbuf = &state->dts_aggbuffer[cpuid]; + dtrace_vstate_t *vstate = &state->dts_vstate; + dtrace_provider_t *prov = probe->dtpr_provider; + uint64_t tracememsize = 0; + int committed = 0; + caddr_t tomax; + + /* + * A little subtlety with the following (seemingly innocuous) + * declaration of the automatic 'val': by looking at the + * code, you might think that it could be declared in the + * action processing loop, below. (That is, it's only used in + * the action processing loop.) However, it must be declared + * out of that scope because in the case of DIF expression + * arguments to aggregating actions, one iteration of the + * action loop will use the last iteration's value. + */ + uint64_t val = 0; + + mstate.dtms_present = DTRACE_MSTATE_ARGS | DTRACE_MSTATE_PROBE; + mstate.dtms_getf = NULL; + + *flags &= ~CPU_DTRACE_ERROR; + + if (prov == dtrace_provider) { + /* + * If dtrace itself is the provider of this probe, + * we're only going to continue processing the ECB if + * arg0 (the dtrace_state_t) is equal to the ECB's + * creating state. (This prevents disjoint consumers + * from seeing one another's metaprobes.) + */ + if (arg0 != (uint64_t)(uintptr_t)state) + continue; + } + + if (state->dts_activity != DTRACE_ACTIVITY_ACTIVE) { + /* + * We're not currently active. If our provider isn't + * the dtrace pseudo provider, we're not interested. + */ + if (prov != dtrace_provider) + continue; + + /* + * Now we must further check if we are in the BEGIN + * probe. If we are, we will only continue processing + * if we're still in WARMUP -- if one BEGIN enabling + * has invoked the exit() action, we don't want to + * evaluate subsequent BEGIN enablings. + */ + if (probe->dtpr_id == dtrace_probeid_begin && + state->dts_activity != DTRACE_ACTIVITY_WARMUP) { + ASSERT(state->dts_activity == + DTRACE_ACTIVITY_DRAINING); + continue; + } + } + + if (ecb->dte_cond) { + /* + * If the dte_cond bits indicate that this + * consumer is only allowed to see user-mode firings + * of this probe, call the provider's dtps_usermode() + * entry point to check that the probe was fired + * while in a user context. Skip this ECB if that's + * not the case. + */ + if ((ecb->dte_cond & DTRACE_COND_USERMODE) && + prov->dtpv_pops.dtps_usermode(prov->dtpv_arg, + probe->dtpr_id, probe->dtpr_arg) == 0) + continue; + +#ifdef illumos + /* + * This is more subtle than it looks. We have to be + * absolutely certain that CRED() isn't going to + * change out from under us so it's only legit to + * examine that structure if we're in constrained + * situations. Currently, the only times we'll this + * check is if a non-super-user has enabled the + * profile or syscall providers -- providers that + * allow visibility of all processes. For the + * profile case, the check above will ensure that + * we're examining a user context. + */ + if (ecb->dte_cond & DTRACE_COND_OWNER) { + cred_t *cr; + cred_t *s_cr = + ecb->dte_state->dts_cred.dcr_cred; + proc_t *proc; + + ASSERT(s_cr != NULL); + + if ((cr = CRED()) == NULL || + s_cr->cr_uid != cr->cr_uid || + s_cr->cr_uid != cr->cr_ruid || + s_cr->cr_uid != cr->cr_suid || + s_cr->cr_gid != cr->cr_gid || + s_cr->cr_gid != cr->cr_rgid || + s_cr->cr_gid != cr->cr_sgid || + (proc = ttoproc(curthread)) == NULL || + (proc->p_flag & SNOCD)) + continue; + } + + if (ecb->dte_cond & DTRACE_COND_ZONEOWNER) { + cred_t *cr; + cred_t *s_cr = + ecb->dte_state->dts_cred.dcr_cred; + + ASSERT(s_cr != NULL); + + if ((cr = CRED()) == NULL || + s_cr->cr_zone->zone_id != + cr->cr_zone->zone_id) + continue; + } +#endif + } + + if (now - state->dts_alive > dtrace_deadman_timeout) { + /* + * We seem to be dead. Unless we (a) have kernel + * destructive permissions (b) have explicitly enabled + * destructive actions and (c) destructive actions have + * not been disabled, we're going to transition into + * the KILLED state, from which no further processing + * on this state will be performed. + */ + if (!dtrace_priv_kernel_destructive(state) || + !state->dts_cred.dcr_destructive || + dtrace_destructive_disallow) { + void *activity = &state->dts_activity; + dtrace_activity_t curstate; + + do { + curstate = state->dts_activity; + } while (dtrace_cas32(activity, curstate, + DTRACE_ACTIVITY_KILLED) != curstate); + + continue; + } + } + + if ((offs = dtrace_buffer_reserve(buf, ecb->dte_needed, + ecb->dte_alignment, state, &mstate)) < 0) + continue; + + tomax = buf->dtb_tomax; + ASSERT(tomax != NULL); + + if (ecb->dte_size != 0) { + dtrace_rechdr_t dtrh; + if (!(mstate.dtms_present & DTRACE_MSTATE_TIMESTAMP)) { + mstate.dtms_timestamp = dtrace_gethrtime(); + mstate.dtms_present |= DTRACE_MSTATE_TIMESTAMP; + } + ASSERT3U(ecb->dte_size, >=, sizeof (dtrace_rechdr_t)); + dtrh.dtrh_epid = ecb->dte_epid; + DTRACE_RECORD_STORE_TIMESTAMP(&dtrh, + mstate.dtms_timestamp); + *((dtrace_rechdr_t *)(tomax + offs)) = dtrh; + } + + mstate.dtms_epid = ecb->dte_epid; + mstate.dtms_present |= DTRACE_MSTATE_EPID; + + if (state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL) + mstate.dtms_access = DTRACE_ACCESS_KERNEL; + else + mstate.dtms_access = 0; + + if (pred != NULL) { + dtrace_difo_t *dp = pred->dtp_difo; + uint64_t rval; + + rval = dtrace_dif_emulate(dp, &mstate, vstate, state); + + if (!(*flags & CPU_DTRACE_ERROR) && !rval) { + dtrace_cacheid_t cid = probe->dtpr_predcache; + + if (cid != DTRACE_CACHEIDNONE && !onintr) { + /* + * Update the predicate cache... + */ + ASSERT(cid == pred->dtp_cacheid); + curthread->t_predcache = cid; + } + + continue; + } + } + + for (act = ecb->dte_action; !(*flags & CPU_DTRACE_ERROR) && + act != NULL; act = act->dta_next) { + size_t valoffs; + dtrace_difo_t *dp; + dtrace_recdesc_t *rec = &act->dta_rec; + + size = rec->dtrd_size; + valoffs = offs + rec->dtrd_offset; + + if (DTRACEACT_ISAGG(act->dta_kind)) { + uint64_t v = 0xbad; + dtrace_aggregation_t *agg; + + agg = (dtrace_aggregation_t *)act; + + if ((dp = act->dta_difo) != NULL) + v = dtrace_dif_emulate(dp, + &mstate, vstate, state); + + if (*flags & CPU_DTRACE_ERROR) + continue; + + /* + * Note that we always pass the expression + * value from the previous iteration of the + * action loop. This value will only be used + * if there is an expression argument to the + * aggregating action, denoted by the + * dtag_hasarg field. + */ + dtrace_aggregate(agg, buf, + offs, aggbuf, v, val); + continue; + } + + switch (act->dta_kind) { + case DTRACEACT_STOP: + if (dtrace_priv_proc_destructive(state)) + dtrace_action_stop(); + continue; + + case DTRACEACT_BREAKPOINT: + if (dtrace_priv_kernel_destructive(state)) + dtrace_action_breakpoint(ecb); + continue; + + case DTRACEACT_PANIC: + if (dtrace_priv_kernel_destructive(state)) + dtrace_action_panic(ecb); + continue; + + case DTRACEACT_STACK: + if (!dtrace_priv_kernel(state)) + continue; + + dtrace_getpcstack((pc_t *)(tomax + valoffs), + size / sizeof (pc_t), probe->dtpr_aframes, + DTRACE_ANCHORED(probe) ? NULL : + (uint32_t *)arg0); + continue; + + case DTRACEACT_JSTACK: + case DTRACEACT_USTACK: + if (!dtrace_priv_proc(state)) + continue; + + /* + * See comment in DIF_VAR_PID. + */ + if (DTRACE_ANCHORED(mstate.dtms_probe) && + CPU_ON_INTR(CPU)) { + int depth = DTRACE_USTACK_NFRAMES( + rec->dtrd_arg) + 1; + + dtrace_bzero((void *)(tomax + valoffs), + DTRACE_USTACK_STRSIZE(rec->dtrd_arg) + + depth * sizeof (uint64_t)); + + continue; + } + + if (DTRACE_USTACK_STRSIZE(rec->dtrd_arg) != 0 && + curproc->p_dtrace_helpers != NULL) { + /* + * This is the slow path -- we have + * allocated string space, and we're + * getting the stack of a process that + * has helpers. Call into a separate + * routine to perform this processing. + */ + dtrace_action_ustack(&mstate, state, + (uint64_t *)(tomax + valoffs), + rec->dtrd_arg); + continue; + } + + DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); + dtrace_getupcstack((uint64_t *) + (tomax + valoffs), + DTRACE_USTACK_NFRAMES(rec->dtrd_arg) + 1); + DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); + continue; + + default: + break; + } + + dp = act->dta_difo; + ASSERT(dp != NULL); + + val = dtrace_dif_emulate(dp, &mstate, vstate, state); + + if (*flags & CPU_DTRACE_ERROR) + continue; + + switch (act->dta_kind) { + case DTRACEACT_SPECULATE: { + dtrace_rechdr_t *dtrh; + + ASSERT(buf == &state->dts_buffer[cpuid]); + buf = dtrace_speculation_buffer(state, + cpuid, val); + + if (buf == NULL) { + *flags |= CPU_DTRACE_DROP; + continue; + } + + offs = dtrace_buffer_reserve(buf, + ecb->dte_needed, ecb->dte_alignment, + state, NULL); + + if (offs < 0) { + *flags |= CPU_DTRACE_DROP; + continue; + } + + tomax = buf->dtb_tomax; + ASSERT(tomax != NULL); + + if (ecb->dte_size == 0) + continue; + + ASSERT3U(ecb->dte_size, >=, + sizeof (dtrace_rechdr_t)); + dtrh = ((void *)(tomax + offs)); + dtrh->dtrh_epid = ecb->dte_epid; + /* + * When the speculation is committed, all of + * the records in the speculative buffer will + * have their timestamps set to the commit + * time. Until then, it is set to a sentinel + * value, for debugability. + */ + DTRACE_RECORD_STORE_TIMESTAMP(dtrh, UINT64_MAX); + continue; + } + + case DTRACEACT_PRINTM: { + /* The DIF returns a 'memref'. */ + uintptr_t *memref = (uintptr_t *)(uintptr_t) val; + + /* Get the size from the memref. */ + size = memref[1]; + + /* + * Check if the size exceeds the allocated + * buffer size. + */ + if (size + sizeof(uintptr_t) > dp->dtdo_rtype.dtdt_size) { + /* Flag a drop! */ + *flags |= CPU_DTRACE_DROP; + continue; + } + + /* Store the size in the buffer first. */ + DTRACE_STORE(uintptr_t, tomax, + valoffs, size); + + /* + * Offset the buffer address to the start + * of the data. + */ + valoffs += sizeof(uintptr_t); + + /* + * Reset to the memory address rather than + * the memref array, then let the BYREF + * code below do the work to store the + * memory data in the buffer. + */ + val = memref[0]; + break; + } + + case DTRACEACT_CHILL: + if (dtrace_priv_kernel_destructive(state)) + dtrace_action_chill(&mstate, val); + continue; + + case DTRACEACT_RAISE: + if (dtrace_priv_proc_destructive(state)) + dtrace_action_raise(val); + continue; + + case DTRACEACT_COMMIT: + ASSERT(!committed); + + /* + * We need to commit our buffer state. + */ + if (ecb->dte_size) + buf->dtb_offset = offs + ecb->dte_size; + buf = &state->dts_buffer[cpuid]; + dtrace_speculation_commit(state, cpuid, val); + committed = 1; + continue; + + case DTRACEACT_DISCARD: + dtrace_speculation_discard(state, cpuid, val); + continue; + + case DTRACEACT_DIFEXPR: + case DTRACEACT_LIBACT: + case DTRACEACT_PRINTF: + case DTRACEACT_PRINTA: + case DTRACEACT_SYSTEM: + case DTRACEACT_FREOPEN: + case DTRACEACT_TRACEMEM: + break; + + case DTRACEACT_TRACEMEM_DYNSIZE: + tracememsize = val; + break; + + case DTRACEACT_SYM: + case DTRACEACT_MOD: + if (!dtrace_priv_kernel(state)) + continue; + break; + + case DTRACEACT_USYM: + case DTRACEACT_UMOD: + case DTRACEACT_UADDR: { +#ifdef illumos + struct pid *pid = curthread->t_procp->p_pidp; +#endif + + if (!dtrace_priv_proc(state)) + continue; + + DTRACE_STORE(uint64_t, tomax, +#ifdef illumos + valoffs, (uint64_t)pid->pid_id); +#else + valoffs, (uint64_t) curproc->p_pid); +#endif + DTRACE_STORE(uint64_t, tomax, + valoffs + sizeof (uint64_t), val); + + continue; + } + + case DTRACEACT_EXIT: { + /* + * For the exit action, we are going to attempt + * to atomically set our activity to be + * draining. If this fails (either because + * another CPU has beat us to the exit action, + * or because our current activity is something + * other than ACTIVE or WARMUP), we will + * continue. This assures that the exit action + * can be successfully recorded at most once + * when we're in the ACTIVE state. If we're + * encountering the exit() action while in + * COOLDOWN, however, we want to honor the new + * status code. (We know that we're the only + * thread in COOLDOWN, so there is no race.) + */ + void *activity = &state->dts_activity; + dtrace_activity_t curstate = state->dts_activity; + + if (curstate == DTRACE_ACTIVITY_COOLDOWN) + break; + + if (curstate != DTRACE_ACTIVITY_WARMUP) + curstate = DTRACE_ACTIVITY_ACTIVE; + + if (dtrace_cas32(activity, curstate, + DTRACE_ACTIVITY_DRAINING) != curstate) { + *flags |= CPU_DTRACE_DROP; + continue; + } + + break; + } + + default: + ASSERT(0); + } + + if (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF || + dp->dtdo_rtype.dtdt_flags & DIF_TF_BYUREF) { + uintptr_t end = valoffs + size; + + if (tracememsize != 0 && + valoffs + tracememsize < end) { + end = valoffs + tracememsize; + tracememsize = 0; + } + + if (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF && + !dtrace_vcanload((void *)(uintptr_t)val, + &dp->dtdo_rtype, NULL, &mstate, vstate)) + continue; + + dtrace_store_by_ref(dp, tomax, size, &valoffs, + &val, end, act->dta_intuple, + dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF ? + DIF_TF_BYREF: DIF_TF_BYUREF); + continue; + } + + switch (size) { + case 0: + break; + + case sizeof (uint8_t): + DTRACE_STORE(uint8_t, tomax, valoffs, val); + break; + case sizeof (uint16_t): + DTRACE_STORE(uint16_t, tomax, valoffs, val); + break; + case sizeof (uint32_t): + DTRACE_STORE(uint32_t, tomax, valoffs, val); + break; + case sizeof (uint64_t): + DTRACE_STORE(uint64_t, tomax, valoffs, val); + break; + default: + /* + * Any other size should have been returned by + * reference, not by value. + */ + ASSERT(0); + break; + } + } + + if (*flags & CPU_DTRACE_DROP) + continue; + + if (*flags & CPU_DTRACE_FAULT) { + int ndx; + dtrace_action_t *err; + + buf->dtb_errors++; + + if (probe->dtpr_id == dtrace_probeid_error) { + /* + * There's nothing we can do -- we had an + * error on the error probe. We bump an + * error counter to at least indicate that + * this condition happened. + */ + dtrace_error(&state->dts_dblerrors); + continue; + } + + if (vtime) { + /* + * Before recursing on dtrace_probe(), we + * need to explicitly clear out our start + * time to prevent it from being accumulated + * into t_dtrace_vtime. + */ + curthread->t_dtrace_start = 0; + } + + /* + * Iterate over the actions to figure out which action + * we were processing when we experienced the error. + * Note that act points _past_ the faulting action; if + * act is ecb->dte_action, the fault was in the + * predicate, if it's ecb->dte_action->dta_next it's + * in action #1, and so on. + */ + for (err = ecb->dte_action, ndx = 0; + err != act; err = err->dta_next, ndx++) + continue; + + dtrace_probe_error(state, ecb->dte_epid, ndx, + (mstate.dtms_present & DTRACE_MSTATE_FLTOFFS) ? + mstate.dtms_fltoffs : -1, DTRACE_FLAGS2FLT(*flags), + cpu_core[cpuid].cpuc_dtrace_illval); + + continue; + } + + if (!committed) + buf->dtb_offset = offs + ecb->dte_size; + } + + if (vtime) + curthread->t_dtrace_start = dtrace_gethrtime(); + + dtrace_probe_exit(cookie); +} + +/* + * DTrace Probe Hashing Functions + * + * The functions in this section (and indeed, the functions in remaining + * sections) are not _called_ from probe context. (Any exceptions to this are + * marked with a "Note:".) Rather, they are called from elsewhere in the + * DTrace framework to look-up probes in, add probes to and remove probes from + * the DTrace probe hashes. (Each probe is hashed by each element of the + * probe tuple -- allowing for fast lookups, regardless of what was + * specified.) + */ +static uint_t +dtrace_hash_str(const char *p) +{ + unsigned int g; + uint_t hval = 0; + + while (*p) { + hval = (hval << 4) + *p++; + if ((g = (hval & 0xf0000000)) != 0) + hval ^= g >> 24; + hval &= ~g; + } + return (hval); +} + +static dtrace_hash_t * +dtrace_hash_create(uintptr_t stroffs, uintptr_t nextoffs, uintptr_t prevoffs) +{ + dtrace_hash_t *hash = kmem_zalloc(sizeof (dtrace_hash_t), KM_SLEEP); + + hash->dth_stroffs = stroffs; + hash->dth_nextoffs = nextoffs; + hash->dth_prevoffs = prevoffs; + + hash->dth_size = 1; + hash->dth_mask = hash->dth_size - 1; + + hash->dth_tab = kmem_zalloc(hash->dth_size * + sizeof (dtrace_hashbucket_t *), KM_SLEEP); + + return (hash); +} + +static void +dtrace_hash_destroy(dtrace_hash_t *hash) +{ +#ifdef DEBUG + int i; + + for (i = 0; i < hash->dth_size; i++) + ASSERT(hash->dth_tab[i] == NULL); +#endif + + kmem_free(hash->dth_tab, + hash->dth_size * sizeof (dtrace_hashbucket_t *)); + kmem_free(hash, sizeof (dtrace_hash_t)); +} + +static void +dtrace_hash_resize(dtrace_hash_t *hash) +{ + int size = hash->dth_size, i, ndx; + int new_size = hash->dth_size << 1; + int new_mask = new_size - 1; + dtrace_hashbucket_t **new_tab, *bucket, *next; + + ASSERT((new_size & new_mask) == 0); + + new_tab = kmem_zalloc(new_size * sizeof (void *), KM_SLEEP); + + for (i = 0; i < size; i++) { + for (bucket = hash->dth_tab[i]; bucket != NULL; bucket = next) { + dtrace_probe_t *probe = bucket->dthb_chain; + + ASSERT(probe != NULL); + ndx = DTRACE_HASHSTR(hash, probe) & new_mask; + + next = bucket->dthb_next; + bucket->dthb_next = new_tab[ndx]; + new_tab[ndx] = bucket; + } + } + + kmem_free(hash->dth_tab, hash->dth_size * sizeof (void *)); + hash->dth_tab = new_tab; + hash->dth_size = new_size; + hash->dth_mask = new_mask; +} + +static void +dtrace_hash_add(dtrace_hash_t *hash, dtrace_probe_t *new) +{ + int hashval = DTRACE_HASHSTR(hash, new); + int ndx = hashval & hash->dth_mask; + dtrace_hashbucket_t *bucket = hash->dth_tab[ndx]; + dtrace_probe_t **nextp, **prevp; + + for (; bucket != NULL; bucket = bucket->dthb_next) { + if (DTRACE_HASHEQ(hash, bucket->dthb_chain, new)) + goto add; + } + + if ((hash->dth_nbuckets >> 1) > hash->dth_size) { + dtrace_hash_resize(hash); + dtrace_hash_add(hash, new); + return; + } + + bucket = kmem_zalloc(sizeof (dtrace_hashbucket_t), KM_SLEEP); + bucket->dthb_next = hash->dth_tab[ndx]; + hash->dth_tab[ndx] = bucket; + hash->dth_nbuckets++; + +add: + nextp = DTRACE_HASHNEXT(hash, new); + ASSERT(*nextp == NULL && *(DTRACE_HASHPREV(hash, new)) == NULL); + *nextp = bucket->dthb_chain; + + if (bucket->dthb_chain != NULL) { + prevp = DTRACE_HASHPREV(hash, bucket->dthb_chain); + ASSERT(*prevp == NULL); + *prevp = new; + } + + bucket->dthb_chain = new; + bucket->dthb_len++; +} + +static dtrace_probe_t * +dtrace_hash_lookup(dtrace_hash_t *hash, dtrace_probe_t *template) +{ + int hashval = DTRACE_HASHSTR(hash, template); + int ndx = hashval & hash->dth_mask; + dtrace_hashbucket_t *bucket = hash->dth_tab[ndx]; + + for (; bucket != NULL; bucket = bucket->dthb_next) { + if (DTRACE_HASHEQ(hash, bucket->dthb_chain, template)) + return (bucket->dthb_chain); + } + + return (NULL); +} + +static int +dtrace_hash_collisions(dtrace_hash_t *hash, dtrace_probe_t *template) +{ + int hashval = DTRACE_HASHSTR(hash, template); + int ndx = hashval & hash->dth_mask; + dtrace_hashbucket_t *bucket = hash->dth_tab[ndx]; + + for (; bucket != NULL; bucket = bucket->dthb_next) { + if (DTRACE_HASHEQ(hash, bucket->dthb_chain, template)) + return (bucket->dthb_len); + } + + return (0); +} + +static void +dtrace_hash_remove(dtrace_hash_t *hash, dtrace_probe_t *probe) +{ + int ndx = DTRACE_HASHSTR(hash, probe) & hash->dth_mask; + dtrace_hashbucket_t *bucket = hash->dth_tab[ndx]; + + dtrace_probe_t **prevp = DTRACE_HASHPREV(hash, probe); + dtrace_probe_t **nextp = DTRACE_HASHNEXT(hash, probe); + + /* + * Find the bucket that we're removing this probe from. + */ + for (; bucket != NULL; bucket = bucket->dthb_next) { + if (DTRACE_HASHEQ(hash, bucket->dthb_chain, probe)) + break; + } + + ASSERT(bucket != NULL); + + if (*prevp == NULL) { + if (*nextp == NULL) { + /* + * The removed probe was the only probe on this + * bucket; we need to remove the bucket. + */ + dtrace_hashbucket_t *b = hash->dth_tab[ndx]; + + ASSERT(bucket->dthb_chain == probe); + ASSERT(b != NULL); + + if (b == bucket) { + hash->dth_tab[ndx] = bucket->dthb_next; + } else { + while (b->dthb_next != bucket) + b = b->dthb_next; + b->dthb_next = bucket->dthb_next; + } + + ASSERT(hash->dth_nbuckets > 0); + hash->dth_nbuckets--; + kmem_free(bucket, sizeof (dtrace_hashbucket_t)); + return; + } + + bucket->dthb_chain = *nextp; + } else { + *(DTRACE_HASHNEXT(hash, *prevp)) = *nextp; + } + + if (*nextp != NULL) + *(DTRACE_HASHPREV(hash, *nextp)) = *prevp; +} + +/* + * DTrace Utility Functions + * + * These are random utility functions that are _not_ called from probe context. + */ +static int +dtrace_badattr(const dtrace_attribute_t *a) +{ + return (a->dtat_name > DTRACE_STABILITY_MAX || + a->dtat_data > DTRACE_STABILITY_MAX || + a->dtat_class > DTRACE_CLASS_MAX); +} + +/* + * Return a duplicate copy of a string. If the specified string is NULL, + * this function returns a zero-length string. + */ +static char * +dtrace_strdup(const char *str) +{ + char *new = kmem_zalloc((str != NULL ? strlen(str) : 0) + 1, KM_SLEEP); + + if (str != NULL) + (void) strcpy(new, str); + + return (new); +} + +#define DTRACE_ISALPHA(c) \ + (((c) >= 'a' && (c) <= 'z') || ((c) >= 'A' && (c) <= 'Z')) + +static int +dtrace_badname(const char *s) +{ + char c; + + if (s == NULL || (c = *s++) == '\0') + return (0); + + if (!DTRACE_ISALPHA(c) && c != '-' && c != '_' && c != '.') + return (1); + + while ((c = *s++) != '\0') { + if (!DTRACE_ISALPHA(c) && (c < '0' || c > '9') && + c != '-' && c != '_' && c != '.' && c != '`') + return (1); + } + + return (0); +} + +static void +dtrace_cred2priv(cred_t *cr, uint32_t *privp, uid_t *uidp, zoneid_t *zoneidp) +{ + uint32_t priv; + +#ifdef illumos + if (cr == NULL || PRIV_POLICY_ONLY(cr, PRIV_ALL, B_FALSE)) { + /* + * For DTRACE_PRIV_ALL, the uid and zoneid don't matter. + */ + priv = DTRACE_PRIV_ALL; + } else { + *uidp = crgetuid(cr); + *zoneidp = crgetzoneid(cr); + + priv = 0; + if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_KERNEL, B_FALSE)) + priv |= DTRACE_PRIV_KERNEL | DTRACE_PRIV_USER; + else if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_USER, B_FALSE)) + priv |= DTRACE_PRIV_USER; + if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_PROC, B_FALSE)) + priv |= DTRACE_PRIV_PROC; + if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE)) + priv |= DTRACE_PRIV_OWNER; + if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE)) + priv |= DTRACE_PRIV_ZONEOWNER; + } +#else + priv = DTRACE_PRIV_ALL; +#endif + + *privp = priv; +} + +#ifdef DTRACE_ERRDEBUG +static void +dtrace_errdebug(const char *str) +{ + int hval = dtrace_hash_str(str) % DTRACE_ERRHASHSZ; + int occupied = 0; + + mutex_enter(&dtrace_errlock); + dtrace_errlast = str; + dtrace_errthread = curthread; + + while (occupied++ < DTRACE_ERRHASHSZ) { + if (dtrace_errhash[hval].dter_msg == str) { + dtrace_errhash[hval].dter_count++; + goto out; + } + + if (dtrace_errhash[hval].dter_msg != NULL) { + hval = (hval + 1) % DTRACE_ERRHASHSZ; + continue; + } + + dtrace_errhash[hval].dter_msg = str; + dtrace_errhash[hval].dter_count = 1; + goto out; + } + + panic("dtrace: undersized error hash"); +out: + mutex_exit(&dtrace_errlock); +} +#endif + +/* + * DTrace Matching Functions + * + * These functions are used to match groups of probes, given some elements of + * a probe tuple, or some globbed expressions for elements of a probe tuple. + */ +static int +dtrace_match_priv(const dtrace_probe_t *prp, uint32_t priv, uid_t uid, + zoneid_t zoneid) +{ + if (priv != DTRACE_PRIV_ALL) { + uint32_t ppriv = prp->dtpr_provider->dtpv_priv.dtpp_flags; + uint32_t match = priv & ppriv; + + /* + * No PRIV_DTRACE_* privileges... + */ + if ((priv & (DTRACE_PRIV_PROC | DTRACE_PRIV_USER | + DTRACE_PRIV_KERNEL)) == 0) + return (0); + + /* + * No matching bits, but there were bits to match... + */ + if (match == 0 && ppriv != 0) + return (0); + + /* + * Need to have permissions to the process, but don't... + */ + if (((ppriv & ~match) & DTRACE_PRIV_OWNER) != 0 && + uid != prp->dtpr_provider->dtpv_priv.dtpp_uid) { + return (0); + } + + /* + * Need to be in the same zone unless we possess the + * privilege to examine all zones. + */ + if (((ppriv & ~match) & DTRACE_PRIV_ZONEOWNER) != 0 && + zoneid != prp->dtpr_provider->dtpv_priv.dtpp_zoneid) { + return (0); + } + } + + return (1); +} + +/* + * dtrace_match_probe compares a dtrace_probe_t to a pre-compiled key, which + * consists of input pattern strings and an ops-vector to evaluate them. + * This function returns >0 for match, 0 for no match, and <0 for error. + */ +static int +dtrace_match_probe(const dtrace_probe_t *prp, const dtrace_probekey_t *pkp, + uint32_t priv, uid_t uid, zoneid_t zoneid) +{ + dtrace_provider_t *pvp = prp->dtpr_provider; + int rv; + + if (pvp->dtpv_defunct) + return (0); + + if ((rv = pkp->dtpk_pmatch(pvp->dtpv_name, pkp->dtpk_prov, 0)) <= 0) + return (rv); + + if ((rv = pkp->dtpk_mmatch(prp->dtpr_mod, pkp->dtpk_mod, 0)) <= 0) + return (rv); + + if ((rv = pkp->dtpk_fmatch(prp->dtpr_func, pkp->dtpk_func, 0)) <= 0) + return (rv); + + if ((rv = pkp->dtpk_nmatch(prp->dtpr_name, pkp->dtpk_name, 0)) <= 0) + return (rv); + + if (dtrace_match_priv(prp, priv, uid, zoneid) == 0) + return (0); + + return (rv); +} + +/* + * dtrace_match_glob() is a safe kernel implementation of the gmatch(3GEN) + * interface for matching a glob pattern 'p' to an input string 's'. Unlike + * libc's version, the kernel version only applies to 8-bit ASCII strings. + * In addition, all of the recursion cases except for '*' matching have been + * unwound. For '*', we still implement recursive evaluation, but a depth + * counter is maintained and matching is aborted if we recurse too deep. + * The function returns 0 if no match, >0 if match, and <0 if recursion error. + */ +static int +dtrace_match_glob(const char *s, const char *p, int depth) +{ + const char *olds; + char s1, c; + int gs; + + if (depth > DTRACE_PROBEKEY_MAXDEPTH) + return (-1); + + if (s == NULL) + s = ""; /* treat NULL as empty string */ + +top: + olds = s; + s1 = *s++; + + if (p == NULL) + return (0); + + if ((c = *p++) == '\0') + return (s1 == '\0'); + + switch (c) { + case '[': { + int ok = 0, notflag = 0; + char lc = '\0'; + + if (s1 == '\0') + return (0); + + if (*p == '!') { + notflag = 1; + p++; + } + + if ((c = *p++) == '\0') + return (0); + + do { + if (c == '-' && lc != '\0' && *p != ']') { + if ((c = *p++) == '\0') + return (0); + if (c == '\\' && (c = *p++) == '\0') + return (0); + + if (notflag) { + if (s1 < lc || s1 > c) + ok++; + else + return (0); + } else if (lc <= s1 && s1 <= c) + ok++; + + } else if (c == '\\' && (c = *p++) == '\0') + return (0); + + lc = c; /* save left-hand 'c' for next iteration */ + + if (notflag) { + if (s1 != c) + ok++; + else + return (0); + } else if (s1 == c) + ok++; + + if ((c = *p++) == '\0') + return (0); + + } while (c != ']'); + + if (ok) + goto top; + + return (0); + } + + case '\\': + if ((c = *p++) == '\0') + return (0); + /*FALLTHRU*/ + + default: + if (c != s1) + return (0); + /*FALLTHRU*/ + + case '?': + if (s1 != '\0') + goto top; + return (0); + + case '*': + while (*p == '*') + p++; /* consecutive *'s are identical to a single one */ + + if (*p == '\0') + return (1); + + for (s = olds; *s != '\0'; s++) { + if ((gs = dtrace_match_glob(s, p, depth + 1)) != 0) + return (gs); + } + + return (0); + } +} + +/*ARGSUSED*/ +static int +dtrace_match_string(const char *s, const char *p, int depth) +{ + return (s != NULL && strcmp(s, p) == 0); +} + +/*ARGSUSED*/ +static int +dtrace_match_nul(const char *s, const char *p, int depth) +{ + return (1); /* always match the empty pattern */ +} + +/*ARGSUSED*/ +static int +dtrace_match_nonzero(const char *s, const char *p, int depth) +{ + return (s != NULL && s[0] != '\0'); +} + +static int +dtrace_match(const dtrace_probekey_t *pkp, uint32_t priv, uid_t uid, + zoneid_t zoneid, int (*matched)(dtrace_probe_t *, void *), void *arg) +{ + dtrace_probe_t template, *probe; + dtrace_hash_t *hash = NULL; + int len, best = INT_MAX, nmatched = 0; + dtrace_id_t i; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + + /* + * If the probe ID is specified in the key, just lookup by ID and + * invoke the match callback once if a matching probe is found. + */ + if (pkp->dtpk_id != DTRACE_IDNONE) { + if ((probe = dtrace_probe_lookup_id(pkp->dtpk_id)) != NULL && + dtrace_match_probe(probe, pkp, priv, uid, zoneid) > 0) { + (void) (*matched)(probe, arg); + nmatched++; + } + return (nmatched); + } + + template.dtpr_mod = (char *)pkp->dtpk_mod; + template.dtpr_func = (char *)pkp->dtpk_func; + template.dtpr_name = (char *)pkp->dtpk_name; + + /* + * We want to find the most distinct of the module name, function + * name, and name. So for each one that is not a glob pattern or + * empty string, we perform a lookup in the corresponding hash and + * use the hash table with the fewest collisions to do our search. + */ + if (pkp->dtpk_mmatch == &dtrace_match_string && + (len = dtrace_hash_collisions(dtrace_bymod, &template)) < best) { + best = len; + hash = dtrace_bymod; + } + + if (pkp->dtpk_fmatch == &dtrace_match_string && + (len = dtrace_hash_collisions(dtrace_byfunc, &template)) < best) { + best = len; + hash = dtrace_byfunc; + } + + if (pkp->dtpk_nmatch == &dtrace_match_string && + (len = dtrace_hash_collisions(dtrace_byname, &template)) < best) { + best = len; + hash = dtrace_byname; + } + + /* + * If we did not select a hash table, iterate over every probe and + * invoke our callback for each one that matches our input probe key. + */ + if (hash == NULL) { + for (i = 0; i < dtrace_nprobes; i++) { + if ((probe = dtrace_probes[i]) == NULL || + dtrace_match_probe(probe, pkp, priv, uid, + zoneid) <= 0) + continue; + + nmatched++; + + if ((*matched)(probe, arg) != DTRACE_MATCH_NEXT) + break; + } + + return (nmatched); + } + + /* + * If we selected a hash table, iterate over each probe of the same key + * name and invoke the callback for every probe that matches the other + * attributes of our input probe key. + */ + for (probe = dtrace_hash_lookup(hash, &template); probe != NULL; + probe = *(DTRACE_HASHNEXT(hash, probe))) { + + if (dtrace_match_probe(probe, pkp, priv, uid, zoneid) <= 0) + continue; + + nmatched++; + + if ((*matched)(probe, arg) != DTRACE_MATCH_NEXT) + break; + } + + return (nmatched); +} + +/* + * Return the function pointer dtrace_probecmp() should use to compare the + * specified pattern with a string. For NULL or empty patterns, we select + * dtrace_match_nul(). For glob pattern strings, we use dtrace_match_glob(). + * For non-empty non-glob strings, we use dtrace_match_string(). + */ +static dtrace_probekey_f * +dtrace_probekey_func(const char *p) +{ + char c; + + if (p == NULL || *p == '\0') + return (&dtrace_match_nul); + + while ((c = *p++) != '\0') { + if (c == '[' || c == '?' || c == '*' || c == '\\') + return (&dtrace_match_glob); + } + + return (&dtrace_match_string); +} + +/* + * Build a probe comparison key for use with dtrace_match_probe() from the + * given probe description. By convention, a null key only matches anchored + * probes: if each field is the empty string, reset dtpk_fmatch to + * dtrace_match_nonzero(). + */ +static void +dtrace_probekey(dtrace_probedesc_t *pdp, dtrace_probekey_t *pkp) +{ + pkp->dtpk_prov = pdp->dtpd_provider; + pkp->dtpk_pmatch = dtrace_probekey_func(pdp->dtpd_provider); + + pkp->dtpk_mod = pdp->dtpd_mod; + pkp->dtpk_mmatch = dtrace_probekey_func(pdp->dtpd_mod); + + pkp->dtpk_func = pdp->dtpd_func; + pkp->dtpk_fmatch = dtrace_probekey_func(pdp->dtpd_func); + + pkp->dtpk_name = pdp->dtpd_name; + pkp->dtpk_nmatch = dtrace_probekey_func(pdp->dtpd_name); + + pkp->dtpk_id = pdp->dtpd_id; + + if (pkp->dtpk_id == DTRACE_IDNONE && + pkp->dtpk_pmatch == &dtrace_match_nul && + pkp->dtpk_mmatch == &dtrace_match_nul && + pkp->dtpk_fmatch == &dtrace_match_nul && + pkp->dtpk_nmatch == &dtrace_match_nul) + pkp->dtpk_fmatch = &dtrace_match_nonzero; +} + +/* + * DTrace Provider-to-Framework API Functions + * + * These functions implement much of the Provider-to-Framework API, as + * described in <sys/dtrace.h>. The parts of the API not in this section are + * the functions in the API for probe management (found below), and + * dtrace_probe() itself (found above). + */ + +/* + * Register the calling provider with the DTrace framework. This should + * generally be called by DTrace providers in their attach(9E) entry point. + */ +int +dtrace_register(const char *name, const dtrace_pattr_t *pap, uint32_t priv, + cred_t *cr, const dtrace_pops_t *pops, void *arg, dtrace_provider_id_t *idp) +{ + dtrace_provider_t *provider; + + if (name == NULL || pap == NULL || pops == NULL || idp == NULL) { + cmn_err(CE_WARN, "failed to register provider '%s': invalid " + "arguments", name ? name : "<NULL>"); + return (EINVAL); + } + + if (name[0] == '\0' || dtrace_badname(name)) { + cmn_err(CE_WARN, "failed to register provider '%s': invalid " + "provider name", name); + return (EINVAL); + } + + if ((pops->dtps_provide == NULL && pops->dtps_provide_module == NULL) || + pops->dtps_enable == NULL || pops->dtps_disable == NULL || + pops->dtps_destroy == NULL || + ((pops->dtps_resume == NULL) != (pops->dtps_suspend == NULL))) { + cmn_err(CE_WARN, "failed to register provider '%s': invalid " + "provider ops", name); + return (EINVAL); + } + + if (dtrace_badattr(&pap->dtpa_provider) || + dtrace_badattr(&pap->dtpa_mod) || + dtrace_badattr(&pap->dtpa_func) || + dtrace_badattr(&pap->dtpa_name) || + dtrace_badattr(&pap->dtpa_args)) { + cmn_err(CE_WARN, "failed to register provider '%s': invalid " + "provider attributes", name); + return (EINVAL); + } + + if (priv & ~DTRACE_PRIV_ALL) { + cmn_err(CE_WARN, "failed to register provider '%s': invalid " + "privilege attributes", name); + return (EINVAL); + } + + if ((priv & DTRACE_PRIV_KERNEL) && + (priv & (DTRACE_PRIV_USER | DTRACE_PRIV_OWNER)) && + pops->dtps_usermode == NULL) { + cmn_err(CE_WARN, "failed to register provider '%s': need " + "dtps_usermode() op for given privilege attributes", name); + return (EINVAL); + } + + provider = kmem_zalloc(sizeof (dtrace_provider_t), KM_SLEEP); + provider->dtpv_name = kmem_alloc(strlen(name) + 1, KM_SLEEP); + (void) strcpy(provider->dtpv_name, name); + + provider->dtpv_attr = *pap; + provider->dtpv_priv.dtpp_flags = priv; + if (cr != NULL) { + provider->dtpv_priv.dtpp_uid = crgetuid(cr); + provider->dtpv_priv.dtpp_zoneid = crgetzoneid(cr); + } + provider->dtpv_pops = *pops; + + if (pops->dtps_provide == NULL) { + ASSERT(pops->dtps_provide_module != NULL); + provider->dtpv_pops.dtps_provide = + (void (*)(void *, dtrace_probedesc_t *))dtrace_nullop; + } + + if (pops->dtps_provide_module == NULL) { + ASSERT(pops->dtps_provide != NULL); + provider->dtpv_pops.dtps_provide_module = + (void (*)(void *, modctl_t *))dtrace_nullop; + } + + if (pops->dtps_suspend == NULL) { + ASSERT(pops->dtps_resume == NULL); + provider->dtpv_pops.dtps_suspend = + (void (*)(void *, dtrace_id_t, void *))dtrace_nullop; + provider->dtpv_pops.dtps_resume = + (void (*)(void *, dtrace_id_t, void *))dtrace_nullop; + } + + provider->dtpv_arg = arg; + *idp = (dtrace_provider_id_t)provider; + + if (pops == &dtrace_provider_ops) { + ASSERT(MUTEX_HELD(&dtrace_provider_lock)); + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(dtrace_anon.dta_enabling == NULL); + + /* + * We make sure that the DTrace provider is at the head of + * the provider chain. + */ + provider->dtpv_next = dtrace_provider; + dtrace_provider = provider; + return (0); + } + + mutex_enter(&dtrace_provider_lock); + mutex_enter(&dtrace_lock); + + /* + * If there is at least one provider registered, we'll add this + * provider after the first provider. + */ + if (dtrace_provider != NULL) { + provider->dtpv_next = dtrace_provider->dtpv_next; + dtrace_provider->dtpv_next = provider; + } else { + dtrace_provider = provider; + } + + if (dtrace_retained != NULL) { + dtrace_enabling_provide(provider); + + /* + * Now we need to call dtrace_enabling_matchall() -- which + * will acquire cpu_lock and dtrace_lock. We therefore need + * to drop all of our locks before calling into it... + */ + mutex_exit(&dtrace_lock); + mutex_exit(&dtrace_provider_lock); + dtrace_enabling_matchall(); + + return (0); + } + + mutex_exit(&dtrace_lock); + mutex_exit(&dtrace_provider_lock); + + return (0); +} + +/* + * Unregister the specified provider from the DTrace framework. This should + * generally be called by DTrace providers in their detach(9E) entry point. + */ +int +dtrace_unregister(dtrace_provider_id_t id) +{ + dtrace_provider_t *old = (dtrace_provider_t *)id; + dtrace_provider_t *prev = NULL; + int i, self = 0, noreap = 0; + dtrace_probe_t *probe, *first = NULL; + + if (old->dtpv_pops.dtps_enable == + (void (*)(void *, dtrace_id_t, void *))dtrace_nullop) { + /* + * If DTrace itself is the provider, we're called with locks + * already held. + */ + ASSERT(old == dtrace_provider); +#ifdef illumos + ASSERT(dtrace_devi != NULL); +#endif + ASSERT(MUTEX_HELD(&dtrace_provider_lock)); + ASSERT(MUTEX_HELD(&dtrace_lock)); + self = 1; + + if (dtrace_provider->dtpv_next != NULL) { + /* + * There's another provider here; return failure. + */ + return (EBUSY); + } + } else { + mutex_enter(&dtrace_provider_lock); +#ifdef illumos + mutex_enter(&mod_lock); +#endif + mutex_enter(&dtrace_lock); + } + + /* + * If anyone has /dev/dtrace open, or if there are anonymous enabled + * probes, we refuse to let providers slither away, unless this + * provider has already been explicitly invalidated. + */ + if (!old->dtpv_defunct && + (dtrace_opens || (dtrace_anon.dta_state != NULL && + dtrace_anon.dta_state->dts_necbs > 0))) { + if (!self) { + mutex_exit(&dtrace_lock); +#ifdef illumos + mutex_exit(&mod_lock); +#endif + mutex_exit(&dtrace_provider_lock); + } + return (EBUSY); + } + + /* + * Attempt to destroy the probes associated with this provider. + */ + for (i = 0; i < dtrace_nprobes; i++) { + if ((probe = dtrace_probes[i]) == NULL) + continue; + + if (probe->dtpr_provider != old) + continue; + + if (probe->dtpr_ecb == NULL) + continue; + + /* + * If we are trying to unregister a defunct provider, and the + * provider was made defunct within the interval dictated by + * dtrace_unregister_defunct_reap, we'll (asynchronously) + * attempt to reap our enablings. To denote that the provider + * should reattempt to unregister itself at some point in the + * future, we will return a differentiable error code (EAGAIN + * instead of EBUSY) in this case. + */ + if (dtrace_gethrtime() - old->dtpv_defunct > + dtrace_unregister_defunct_reap) + noreap = 1; + + if (!self) { + mutex_exit(&dtrace_lock); +#ifdef illumos + mutex_exit(&mod_lock); +#endif + mutex_exit(&dtrace_provider_lock); + } + + if (noreap) + return (EBUSY); + + (void) taskq_dispatch(dtrace_taskq, + (task_func_t *)dtrace_enabling_reap, NULL, TQ_SLEEP); + + return (EAGAIN); + } + + /* + * All of the probes for this provider are disabled; we can safely + * remove all of them from their hash chains and from the probe array. + */ + for (i = 0; i < dtrace_nprobes; i++) { + if ((probe = dtrace_probes[i]) == NULL) + continue; + + if (probe->dtpr_provider != old) + continue; + + dtrace_probes[i] = NULL; + + dtrace_hash_remove(dtrace_bymod, probe); + dtrace_hash_remove(dtrace_byfunc, probe); + dtrace_hash_remove(dtrace_byname, probe); + + if (first == NULL) { + first = probe; + probe->dtpr_nextmod = NULL; + } else { + probe->dtpr_nextmod = first; + first = probe; + } + } + + /* + * The provider's probes have been removed from the hash chains and + * from the probe array. Now issue a dtrace_sync() to be sure that + * everyone has cleared out from any probe array processing. + */ + dtrace_sync(); + + for (probe = first; probe != NULL; probe = first) { + first = probe->dtpr_nextmod; + + old->dtpv_pops.dtps_destroy(old->dtpv_arg, probe->dtpr_id, + probe->dtpr_arg); + kmem_free(probe->dtpr_mod, strlen(probe->dtpr_mod) + 1); + kmem_free(probe->dtpr_func, strlen(probe->dtpr_func) + 1); + kmem_free(probe->dtpr_name, strlen(probe->dtpr_name) + 1); +#ifdef illumos + vmem_free(dtrace_arena, (void *)(uintptr_t)(probe->dtpr_id), 1); +#else + free_unr(dtrace_arena, probe->dtpr_id); +#endif + kmem_free(probe, sizeof (dtrace_probe_t)); + } + + if ((prev = dtrace_provider) == old) { +#ifdef illumos + ASSERT(self || dtrace_devi == NULL); + ASSERT(old->dtpv_next == NULL || dtrace_devi == NULL); +#endif + dtrace_provider = old->dtpv_next; + } else { + while (prev != NULL && prev->dtpv_next != old) + prev = prev->dtpv_next; + + if (prev == NULL) { + panic("attempt to unregister non-existent " + "dtrace provider %p\n", (void *)id); + } + + prev->dtpv_next = old->dtpv_next; + } + + if (!self) { + mutex_exit(&dtrace_lock); +#ifdef illumos + mutex_exit(&mod_lock); +#endif + mutex_exit(&dtrace_provider_lock); + } + + kmem_free(old->dtpv_name, strlen(old->dtpv_name) + 1); + kmem_free(old, sizeof (dtrace_provider_t)); + + return (0); +} + +/* + * Invalidate the specified provider. All subsequent probe lookups for the + * specified provider will fail, but its probes will not be removed. + */ +void +dtrace_invalidate(dtrace_provider_id_t id) +{ + dtrace_provider_t *pvp = (dtrace_provider_t *)id; + + ASSERT(pvp->dtpv_pops.dtps_enable != + (void (*)(void *, dtrace_id_t, void *))dtrace_nullop); + + mutex_enter(&dtrace_provider_lock); + mutex_enter(&dtrace_lock); + + pvp->dtpv_defunct = dtrace_gethrtime(); + + mutex_exit(&dtrace_lock); + mutex_exit(&dtrace_provider_lock); +} + +/* + * Indicate whether or not DTrace has attached. + */ +int +dtrace_attached(void) +{ + /* + * dtrace_provider will be non-NULL iff the DTrace driver has + * attached. (It's non-NULL because DTrace is always itself a + * provider.) + */ + return (dtrace_provider != NULL); +} + +/* + * Remove all the unenabled probes for the given provider. This function is + * not unlike dtrace_unregister(), except that it doesn't remove the provider + * -- just as many of its associated probes as it can. + */ +int +dtrace_condense(dtrace_provider_id_t id) +{ + dtrace_provider_t *prov = (dtrace_provider_t *)id; + int i; + dtrace_probe_t *probe; + + /* + * Make sure this isn't the dtrace provider itself. + */ + ASSERT(prov->dtpv_pops.dtps_enable != + (void (*)(void *, dtrace_id_t, void *))dtrace_nullop); + + mutex_enter(&dtrace_provider_lock); + mutex_enter(&dtrace_lock); + + /* + * Attempt to destroy the probes associated with this provider. + */ + for (i = 0; i < dtrace_nprobes; i++) { + if ((probe = dtrace_probes[i]) == NULL) + continue; + + if (probe->dtpr_provider != prov) + continue; + + if (probe->dtpr_ecb != NULL) + continue; + + dtrace_probes[i] = NULL; + + dtrace_hash_remove(dtrace_bymod, probe); + dtrace_hash_remove(dtrace_byfunc, probe); + dtrace_hash_remove(dtrace_byname, probe); + + prov->dtpv_pops.dtps_destroy(prov->dtpv_arg, i + 1, + probe->dtpr_arg); + kmem_free(probe->dtpr_mod, strlen(probe->dtpr_mod) + 1); + kmem_free(probe->dtpr_func, strlen(probe->dtpr_func) + 1); + kmem_free(probe->dtpr_name, strlen(probe->dtpr_name) + 1); + kmem_free(probe, sizeof (dtrace_probe_t)); +#ifdef illumos + vmem_free(dtrace_arena, (void *)((uintptr_t)i + 1), 1); +#else + free_unr(dtrace_arena, i + 1); +#endif + } + + mutex_exit(&dtrace_lock); + mutex_exit(&dtrace_provider_lock); + + return (0); +} + +/* + * DTrace Probe Management Functions + * + * The functions in this section perform the DTrace probe management, + * including functions to create probes, look-up probes, and call into the + * providers to request that probes be provided. Some of these functions are + * in the Provider-to-Framework API; these functions can be identified by the + * fact that they are not declared "static". + */ + +/* + * Create a probe with the specified module name, function name, and name. + */ +dtrace_id_t +dtrace_probe_create(dtrace_provider_id_t prov, const char *mod, + const char *func, const char *name, int aframes, void *arg) +{ + dtrace_probe_t *probe, **probes; + dtrace_provider_t *provider = (dtrace_provider_t *)prov; + dtrace_id_t id; + + if (provider == dtrace_provider) { + ASSERT(MUTEX_HELD(&dtrace_lock)); + } else { + mutex_enter(&dtrace_lock); + } + +#ifdef illumos + id = (dtrace_id_t)(uintptr_t)vmem_alloc(dtrace_arena, 1, + VM_BESTFIT | VM_SLEEP); +#else + id = alloc_unr(dtrace_arena); +#endif + probe = kmem_zalloc(sizeof (dtrace_probe_t), KM_SLEEP); + + probe->dtpr_id = id; + probe->dtpr_gen = dtrace_probegen++; + probe->dtpr_mod = dtrace_strdup(mod); + probe->dtpr_func = dtrace_strdup(func); + probe->dtpr_name = dtrace_strdup(name); + probe->dtpr_arg = arg; + probe->dtpr_aframes = aframes; + probe->dtpr_provider = provider; + + dtrace_hash_add(dtrace_bymod, probe); + dtrace_hash_add(dtrace_byfunc, probe); + dtrace_hash_add(dtrace_byname, probe); + + if (id - 1 >= dtrace_nprobes) { + size_t osize = dtrace_nprobes * sizeof (dtrace_probe_t *); + size_t nsize = osize << 1; + + if (nsize == 0) { + ASSERT(osize == 0); + ASSERT(dtrace_probes == NULL); + nsize = sizeof (dtrace_probe_t *); + } + + probes = kmem_zalloc(nsize, KM_SLEEP); + + if (dtrace_probes == NULL) { + ASSERT(osize == 0); + dtrace_probes = probes; + dtrace_nprobes = 1; + } else { + dtrace_probe_t **oprobes = dtrace_probes; + + bcopy(oprobes, probes, osize); + dtrace_membar_producer(); + dtrace_probes = probes; + + dtrace_sync(); + + /* + * All CPUs are now seeing the new probes array; we can + * safely free the old array. + */ + kmem_free(oprobes, osize); + dtrace_nprobes <<= 1; + } + + ASSERT(id - 1 < dtrace_nprobes); + } + + ASSERT(dtrace_probes[id - 1] == NULL); + dtrace_probes[id - 1] = probe; + + if (provider != dtrace_provider) + mutex_exit(&dtrace_lock); + + return (id); +} + +static dtrace_probe_t * +dtrace_probe_lookup_id(dtrace_id_t id) +{ + ASSERT(MUTEX_HELD(&dtrace_lock)); + + if (id == 0 || id > dtrace_nprobes) + return (NULL); + + return (dtrace_probes[id - 1]); +} + +static int +dtrace_probe_lookup_match(dtrace_probe_t *probe, void *arg) +{ + *((dtrace_id_t *)arg) = probe->dtpr_id; + + return (DTRACE_MATCH_DONE); +} + +/* + * Look up a probe based on provider and one or more of module name, function + * name and probe name. + */ +dtrace_id_t +dtrace_probe_lookup(dtrace_provider_id_t prid, char *mod, + char *func, char *name) +{ + dtrace_probekey_t pkey; + dtrace_id_t id; + int match; + + pkey.dtpk_prov = ((dtrace_provider_t *)prid)->dtpv_name; + pkey.dtpk_pmatch = &dtrace_match_string; + pkey.dtpk_mod = mod; + pkey.dtpk_mmatch = mod ? &dtrace_match_string : &dtrace_match_nul; + pkey.dtpk_func = func; + pkey.dtpk_fmatch = func ? &dtrace_match_string : &dtrace_match_nul; + pkey.dtpk_name = name; + pkey.dtpk_nmatch = name ? &dtrace_match_string : &dtrace_match_nul; + pkey.dtpk_id = DTRACE_IDNONE; + + mutex_enter(&dtrace_lock); + match = dtrace_match(&pkey, DTRACE_PRIV_ALL, 0, 0, + dtrace_probe_lookup_match, &id); + mutex_exit(&dtrace_lock); + + ASSERT(match == 1 || match == 0); + return (match ? id : 0); +} + +/* + * Returns the probe argument associated with the specified probe. + */ +void * +dtrace_probe_arg(dtrace_provider_id_t id, dtrace_id_t pid) +{ + dtrace_probe_t *probe; + void *rval = NULL; + + mutex_enter(&dtrace_lock); + + if ((probe = dtrace_probe_lookup_id(pid)) != NULL && + probe->dtpr_provider == (dtrace_provider_t *)id) + rval = probe->dtpr_arg; + + mutex_exit(&dtrace_lock); + + return (rval); +} + +/* + * Copy a probe into a probe description. + */ +static void +dtrace_probe_description(const dtrace_probe_t *prp, dtrace_probedesc_t *pdp) +{ + bzero(pdp, sizeof (dtrace_probedesc_t)); + pdp->dtpd_id = prp->dtpr_id; + + (void) strncpy(pdp->dtpd_provider, + prp->dtpr_provider->dtpv_name, DTRACE_PROVNAMELEN - 1); + + (void) strncpy(pdp->dtpd_mod, prp->dtpr_mod, DTRACE_MODNAMELEN - 1); + (void) strncpy(pdp->dtpd_func, prp->dtpr_func, DTRACE_FUNCNAMELEN - 1); + (void) strncpy(pdp->dtpd_name, prp->dtpr_name, DTRACE_NAMELEN - 1); +} + +/* + * Called to indicate that a probe -- or probes -- should be provided by a + * specfied provider. If the specified description is NULL, the provider will + * be told to provide all of its probes. (This is done whenever a new + * consumer comes along, or whenever a retained enabling is to be matched.) If + * the specified description is non-NULL, the provider is given the + * opportunity to dynamically provide the specified probe, allowing providers + * to support the creation of probes on-the-fly. (So-called _autocreated_ + * probes.) If the provider is NULL, the operations will be applied to all + * providers; if the provider is non-NULL the operations will only be applied + * to the specified provider. The dtrace_provider_lock must be held, and the + * dtrace_lock must _not_ be held -- the provider's dtps_provide() operation + * will need to grab the dtrace_lock when it reenters the framework through + * dtrace_probe_lookup(), dtrace_probe_create(), etc. + */ +static void +dtrace_probe_provide(dtrace_probedesc_t *desc, dtrace_provider_t *prv) +{ +#ifdef illumos + modctl_t *ctl; +#endif + int all = 0; + + ASSERT(MUTEX_HELD(&dtrace_provider_lock)); + + if (prv == NULL) { + all = 1; + prv = dtrace_provider; + } + + do { + /* + * First, call the blanket provide operation. + */ + prv->dtpv_pops.dtps_provide(prv->dtpv_arg, desc); + +#ifdef illumos + /* + * Now call the per-module provide operation. We will grab + * mod_lock to prevent the list from being modified. Note + * that this also prevents the mod_busy bits from changing. + * (mod_busy can only be changed with mod_lock held.) + */ + mutex_enter(&mod_lock); + + ctl = &modules; + do { + if (ctl->mod_busy || ctl->mod_mp == NULL) + continue; + + prv->dtpv_pops.dtps_provide_module(prv->dtpv_arg, ctl); + + } while ((ctl = ctl->mod_next) != &modules); + + mutex_exit(&mod_lock); +#endif + } while (all && (prv = prv->dtpv_next) != NULL); +} + +#ifdef illumos +/* + * Iterate over each probe, and call the Framework-to-Provider API function + * denoted by offs. + */ +static void +dtrace_probe_foreach(uintptr_t offs) +{ + dtrace_provider_t *prov; + void (*func)(void *, dtrace_id_t, void *); + dtrace_probe_t *probe; + dtrace_icookie_t cookie; + int i; + + /* + * We disable interrupts to walk through the probe array. This is + * safe -- the dtrace_sync() in dtrace_unregister() assures that we + * won't see stale data. + */ + cookie = dtrace_interrupt_disable(); + + for (i = 0; i < dtrace_nprobes; i++) { + if ((probe = dtrace_probes[i]) == NULL) + continue; + + if (probe->dtpr_ecb == NULL) { + /* + * This probe isn't enabled -- don't call the function. + */ + continue; + } + + prov = probe->dtpr_provider; + func = *((void(**)(void *, dtrace_id_t, void *)) + ((uintptr_t)&prov->dtpv_pops + offs)); + + func(prov->dtpv_arg, i + 1, probe->dtpr_arg); + } + + dtrace_interrupt_enable(cookie); +} +#endif + +static int +dtrace_probe_enable(dtrace_probedesc_t *desc, dtrace_enabling_t *enab) +{ + dtrace_probekey_t pkey; + uint32_t priv; + uid_t uid; + zoneid_t zoneid; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + dtrace_ecb_create_cache = NULL; + + if (desc == NULL) { + /* + * If we're passed a NULL description, we're being asked to + * create an ECB with a NULL probe. + */ + (void) dtrace_ecb_create_enable(NULL, enab); + return (0); + } + + dtrace_probekey(desc, &pkey); + dtrace_cred2priv(enab->dten_vstate->dtvs_state->dts_cred.dcr_cred, + &priv, &uid, &zoneid); + + return (dtrace_match(&pkey, priv, uid, zoneid, dtrace_ecb_create_enable, + enab)); +} + +/* + * DTrace Helper Provider Functions + */ +static void +dtrace_dofattr2attr(dtrace_attribute_t *attr, const dof_attr_t dofattr) +{ + attr->dtat_name = DOF_ATTR_NAME(dofattr); + attr->dtat_data = DOF_ATTR_DATA(dofattr); + attr->dtat_class = DOF_ATTR_CLASS(dofattr); +} + +static void +dtrace_dofprov2hprov(dtrace_helper_provdesc_t *hprov, + const dof_provider_t *dofprov, char *strtab) +{ + hprov->dthpv_provname = strtab + dofprov->dofpv_name; + dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_provider, + dofprov->dofpv_provattr); + dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_mod, + dofprov->dofpv_modattr); + dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_func, + dofprov->dofpv_funcattr); + dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_name, + dofprov->dofpv_nameattr); + dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_args, + dofprov->dofpv_argsattr); +} + +static void +dtrace_helper_provide_one(dof_helper_t *dhp, dof_sec_t *sec, pid_t pid) +{ + uintptr_t daddr = (uintptr_t)dhp->dofhp_dof; + dof_hdr_t *dof = (dof_hdr_t *)daddr; + dof_sec_t *str_sec, *prb_sec, *arg_sec, *off_sec, *enoff_sec; + dof_provider_t *provider; + dof_probe_t *probe; + uint32_t *off, *enoff; + uint8_t *arg; + char *strtab; + uint_t i, nprobes; + dtrace_helper_provdesc_t dhpv; + dtrace_helper_probedesc_t dhpb; + dtrace_meta_t *meta = dtrace_meta_pid; + dtrace_mops_t *mops = &meta->dtm_mops; + void *parg; + + provider = (dof_provider_t *)(uintptr_t)(daddr + sec->dofs_offset); + str_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff + + provider->dofpv_strtab * dof->dofh_secsize); + prb_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff + + provider->dofpv_probes * dof->dofh_secsize); + arg_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff + + provider->dofpv_prargs * dof->dofh_secsize); + off_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff + + provider->dofpv_proffs * dof->dofh_secsize); + + strtab = (char *)(uintptr_t)(daddr + str_sec->dofs_offset); + off = (uint32_t *)(uintptr_t)(daddr + off_sec->dofs_offset); + arg = (uint8_t *)(uintptr_t)(daddr + arg_sec->dofs_offset); + enoff = NULL; + + /* + * See dtrace_helper_provider_validate(). + */ + if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1 && + provider->dofpv_prenoffs != DOF_SECT_NONE) { + enoff_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff + + provider->dofpv_prenoffs * dof->dofh_secsize); + enoff = (uint32_t *)(uintptr_t)(daddr + enoff_sec->dofs_offset); + } + + nprobes = prb_sec->dofs_size / prb_sec->dofs_entsize; + + /* + * Create the provider. + */ + dtrace_dofprov2hprov(&dhpv, provider, strtab); + + if ((parg = mops->dtms_provide_pid(meta->dtm_arg, &dhpv, pid)) == NULL) + return; + + meta->dtm_count++; + + /* + * Create the probes. + */ + for (i = 0; i < nprobes; i++) { + probe = (dof_probe_t *)(uintptr_t)(daddr + + prb_sec->dofs_offset + i * prb_sec->dofs_entsize); + + /* See the check in dtrace_helper_provider_validate(). */ + if (strlen(strtab + probe->dofpr_func) >= DTRACE_FUNCNAMELEN) + continue; + + dhpb.dthpb_mod = dhp->dofhp_mod; + dhpb.dthpb_func = strtab + probe->dofpr_func; + dhpb.dthpb_name = strtab + probe->dofpr_name; + dhpb.dthpb_base = probe->dofpr_addr; + dhpb.dthpb_offs = off + probe->dofpr_offidx; + dhpb.dthpb_noffs = probe->dofpr_noffs; + if (enoff != NULL) { + dhpb.dthpb_enoffs = enoff + probe->dofpr_enoffidx; + dhpb.dthpb_nenoffs = probe->dofpr_nenoffs; + } else { + dhpb.dthpb_enoffs = NULL; + dhpb.dthpb_nenoffs = 0; + } + dhpb.dthpb_args = arg + probe->dofpr_argidx; + dhpb.dthpb_nargc = probe->dofpr_nargc; + dhpb.dthpb_xargc = probe->dofpr_xargc; + dhpb.dthpb_ntypes = strtab + probe->dofpr_nargv; + dhpb.dthpb_xtypes = strtab + probe->dofpr_xargv; + + mops->dtms_create_probe(meta->dtm_arg, parg, &dhpb); + } +} + +static void +dtrace_helper_provide(dof_helper_t *dhp, pid_t pid) +{ + uintptr_t daddr = (uintptr_t)dhp->dofhp_dof; + dof_hdr_t *dof = (dof_hdr_t *)daddr; + int i; + + ASSERT(MUTEX_HELD(&dtrace_meta_lock)); + + for (i = 0; i < dof->dofh_secnum; i++) { + dof_sec_t *sec = (dof_sec_t *)(uintptr_t)(daddr + + dof->dofh_secoff + i * dof->dofh_secsize); + + if (sec->dofs_type != DOF_SECT_PROVIDER) + continue; + + dtrace_helper_provide_one(dhp, sec, pid); + } + + /* + * We may have just created probes, so we must now rematch against + * any retained enablings. Note that this call will acquire both + * cpu_lock and dtrace_lock; the fact that we are holding + * dtrace_meta_lock now is what defines the ordering with respect to + * these three locks. + */ + dtrace_enabling_matchall(); +} + +static void +dtrace_helper_provider_remove_one(dof_helper_t *dhp, dof_sec_t *sec, pid_t pid) +{ + uintptr_t daddr = (uintptr_t)dhp->dofhp_dof; + dof_hdr_t *dof = (dof_hdr_t *)daddr; + dof_sec_t *str_sec; + dof_provider_t *provider; + char *strtab; + dtrace_helper_provdesc_t dhpv; + dtrace_meta_t *meta = dtrace_meta_pid; + dtrace_mops_t *mops = &meta->dtm_mops; + + provider = (dof_provider_t *)(uintptr_t)(daddr + sec->dofs_offset); + str_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff + + provider->dofpv_strtab * dof->dofh_secsize); + + strtab = (char *)(uintptr_t)(daddr + str_sec->dofs_offset); + + /* + * Create the provider. + */ + dtrace_dofprov2hprov(&dhpv, provider, strtab); + + mops->dtms_remove_pid(meta->dtm_arg, &dhpv, pid); + + meta->dtm_count--; +} + +static void +dtrace_helper_provider_remove(dof_helper_t *dhp, pid_t pid) +{ + uintptr_t daddr = (uintptr_t)dhp->dofhp_dof; + dof_hdr_t *dof = (dof_hdr_t *)daddr; + int i; + + ASSERT(MUTEX_HELD(&dtrace_meta_lock)); + + for (i = 0; i < dof->dofh_secnum; i++) { + dof_sec_t *sec = (dof_sec_t *)(uintptr_t)(daddr + + dof->dofh_secoff + i * dof->dofh_secsize); + + if (sec->dofs_type != DOF_SECT_PROVIDER) + continue; + + dtrace_helper_provider_remove_one(dhp, sec, pid); + } +} + +/* + * DTrace Meta Provider-to-Framework API Functions + * + * These functions implement the Meta Provider-to-Framework API, as described + * in <sys/dtrace.h>. + */ +int +dtrace_meta_register(const char *name, const dtrace_mops_t *mops, void *arg, + dtrace_meta_provider_id_t *idp) +{ + dtrace_meta_t *meta; + dtrace_helpers_t *help, *next; + int i; + + *idp = DTRACE_METAPROVNONE; + + /* + * We strictly don't need the name, but we hold onto it for + * debuggability. All hail error queues! + */ + if (name == NULL) { + cmn_err(CE_WARN, "failed to register meta-provider: " + "invalid name"); + return (EINVAL); + } + + if (mops == NULL || + mops->dtms_create_probe == NULL || + mops->dtms_provide_pid == NULL || + mops->dtms_remove_pid == NULL) { + cmn_err(CE_WARN, "failed to register meta-register %s: " + "invalid ops", name); + return (EINVAL); + } + + meta = kmem_zalloc(sizeof (dtrace_meta_t), KM_SLEEP); + meta->dtm_mops = *mops; + meta->dtm_name = kmem_alloc(strlen(name) + 1, KM_SLEEP); + (void) strcpy(meta->dtm_name, name); + meta->dtm_arg = arg; + + mutex_enter(&dtrace_meta_lock); + mutex_enter(&dtrace_lock); + + if (dtrace_meta_pid != NULL) { + mutex_exit(&dtrace_lock); + mutex_exit(&dtrace_meta_lock); + cmn_err(CE_WARN, "failed to register meta-register %s: " + "user-land meta-provider exists", name); + kmem_free(meta->dtm_name, strlen(meta->dtm_name) + 1); + kmem_free(meta, sizeof (dtrace_meta_t)); + return (EINVAL); + } + + dtrace_meta_pid = meta; + *idp = (dtrace_meta_provider_id_t)meta; + + /* + * If there are providers and probes ready to go, pass them + * off to the new meta provider now. + */ + + help = dtrace_deferred_pid; + dtrace_deferred_pid = NULL; + + mutex_exit(&dtrace_lock); + + while (help != NULL) { + for (i = 0; i < help->dthps_nprovs; i++) { + dtrace_helper_provide(&help->dthps_provs[i]->dthp_prov, + help->dthps_pid); + } + + next = help->dthps_next; + help->dthps_next = NULL; + help->dthps_prev = NULL; + help->dthps_deferred = 0; + help = next; + } + + mutex_exit(&dtrace_meta_lock); + + return (0); +} + +int +dtrace_meta_unregister(dtrace_meta_provider_id_t id) +{ + dtrace_meta_t **pp, *old = (dtrace_meta_t *)id; + + mutex_enter(&dtrace_meta_lock); + mutex_enter(&dtrace_lock); + + if (old == dtrace_meta_pid) { + pp = &dtrace_meta_pid; + } else { + panic("attempt to unregister non-existent " + "dtrace meta-provider %p\n", (void *)old); + } + + if (old->dtm_count != 0) { + mutex_exit(&dtrace_lock); + mutex_exit(&dtrace_meta_lock); + return (EBUSY); + } + + *pp = NULL; + + mutex_exit(&dtrace_lock); + mutex_exit(&dtrace_meta_lock); + + kmem_free(old->dtm_name, strlen(old->dtm_name) + 1); + kmem_free(old, sizeof (dtrace_meta_t)); + + return (0); +} + + +/* + * DTrace DIF Object Functions + */ +static int +dtrace_difo_err(uint_t pc, const char *format, ...) +{ + if (dtrace_err_verbose) { + va_list alist; + + (void) uprintf("dtrace DIF object error: [%u]: ", pc); + va_start(alist, format); + (void) vuprintf(format, alist); + va_end(alist); + } + +#ifdef DTRACE_ERRDEBUG + dtrace_errdebug(format); +#endif + return (1); +} + +/* + * Validate a DTrace DIF object by checking the IR instructions. The following + * rules are currently enforced by dtrace_difo_validate(): + * + * 1. Each instruction must have a valid opcode + * 2. Each register, string, variable, or subroutine reference must be valid + * 3. No instruction can modify register %r0 (must be zero) + * 4. All instruction reserved bits must be set to zero + * 5. The last instruction must be a "ret" instruction + * 6. All branch targets must reference a valid instruction _after_ the branch + */ +static int +dtrace_difo_validate(dtrace_difo_t *dp, dtrace_vstate_t *vstate, uint_t nregs, + cred_t *cr) +{ + int err = 0, i; + int (*efunc)(uint_t pc, const char *, ...) = dtrace_difo_err; + int kcheckload; + uint_t pc; + int maxglobal = -1, maxlocal = -1, maxtlocal = -1; + + kcheckload = cr == NULL || + (vstate->dtvs_state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL) == 0; + + dp->dtdo_destructive = 0; + + for (pc = 0; pc < dp->dtdo_len && err == 0; pc++) { + dif_instr_t instr = dp->dtdo_buf[pc]; + + uint_t r1 = DIF_INSTR_R1(instr); + uint_t r2 = DIF_INSTR_R2(instr); + uint_t rd = DIF_INSTR_RD(instr); + uint_t rs = DIF_INSTR_RS(instr); + uint_t label = DIF_INSTR_LABEL(instr); + uint_t v = DIF_INSTR_VAR(instr); + uint_t subr = DIF_INSTR_SUBR(instr); + uint_t type = DIF_INSTR_TYPE(instr); + uint_t op = DIF_INSTR_OP(instr); + + switch (op) { + case DIF_OP_OR: + case DIF_OP_XOR: + case DIF_OP_AND: + case DIF_OP_SLL: + case DIF_OP_SRL: + case DIF_OP_SRA: + case DIF_OP_SUB: + case DIF_OP_ADD: + case DIF_OP_MUL: + case DIF_OP_SDIV: + case DIF_OP_UDIV: + case DIF_OP_SREM: + case DIF_OP_UREM: + case DIF_OP_COPYS: + if (r1 >= nregs) + err += efunc(pc, "invalid register %u\n", r1); + if (r2 >= nregs) + err += efunc(pc, "invalid register %u\n", r2); + if (rd >= nregs) + err += efunc(pc, "invalid register %u\n", rd); + if (rd == 0) + err += efunc(pc, "cannot write to %r0\n"); + break; + case DIF_OP_NOT: + case DIF_OP_MOV: + case DIF_OP_ALLOCS: + if (r1 >= nregs) + err += efunc(pc, "invalid register %u\n", r1); + if (r2 != 0) + err += efunc(pc, "non-zero reserved bits\n"); + if (rd >= nregs) + err += efunc(pc, "invalid register %u\n", rd); + if (rd == 0) + err += efunc(pc, "cannot write to %r0\n"); + break; + case DIF_OP_LDSB: + case DIF_OP_LDSH: + case DIF_OP_LDSW: + case DIF_OP_LDUB: + case DIF_OP_LDUH: + case DIF_OP_LDUW: + case DIF_OP_LDX: + if (r1 >= nregs) + err += efunc(pc, "invalid register %u\n", r1); + if (r2 != 0) + err += efunc(pc, "non-zero reserved bits\n"); + if (rd >= nregs) + err += efunc(pc, "invalid register %u\n", rd); + if (rd == 0) + err += efunc(pc, "cannot write to %r0\n"); + if (kcheckload) + dp->dtdo_buf[pc] = DIF_INSTR_LOAD(op + + DIF_OP_RLDSB - DIF_OP_LDSB, r1, rd); + break; + case DIF_OP_RLDSB: + case DIF_OP_RLDSH: + case DIF_OP_RLDSW: + case DIF_OP_RLDUB: + case DIF_OP_RLDUH: + case DIF_OP_RLDUW: + case DIF_OP_RLDX: + if (r1 >= nregs) + err += efunc(pc, "invalid register %u\n", r1); + if (r2 != 0) + err += efunc(pc, "non-zero reserved bits\n"); + if (rd >= nregs) + err += efunc(pc, "invalid register %u\n", rd); + if (rd == 0) + err += efunc(pc, "cannot write to %r0\n"); + break; + case DIF_OP_ULDSB: + case DIF_OP_ULDSH: + case DIF_OP_ULDSW: + case DIF_OP_ULDUB: + case DIF_OP_ULDUH: + case DIF_OP_ULDUW: + case DIF_OP_ULDX: + if (r1 >= nregs) + err += efunc(pc, "invalid register %u\n", r1); + if (r2 != 0) + err += efunc(pc, "non-zero reserved bits\n"); + if (rd >= nregs) + err += efunc(pc, "invalid register %u\n", rd); + if (rd == 0) + err += efunc(pc, "cannot write to %r0\n"); + break; + case DIF_OP_STB: + case DIF_OP_STH: + case DIF_OP_STW: + case DIF_OP_STX: + if (r1 >= nregs) + err += efunc(pc, "invalid register %u\n", r1); + if (r2 != 0) + err += efunc(pc, "non-zero reserved bits\n"); + if (rd >= nregs) + err += efunc(pc, "invalid register %u\n", rd); + if (rd == 0) + err += efunc(pc, "cannot write to 0 address\n"); + break; + case DIF_OP_CMP: + case DIF_OP_SCMP: + if (r1 >= nregs) + err += efunc(pc, "invalid register %u\n", r1); + if (r2 >= nregs) + err += efunc(pc, "invalid register %u\n", r2); + if (rd != 0) + err += efunc(pc, "non-zero reserved bits\n"); + break; + case DIF_OP_TST: + if (r1 >= nregs) + err += efunc(pc, "invalid register %u\n", r1); + if (r2 != 0 || rd != 0) + err += efunc(pc, "non-zero reserved bits\n"); + break; + case DIF_OP_BA: + case DIF_OP_BE: + case DIF_OP_BNE: + case DIF_OP_BG: + case DIF_OP_BGU: + case DIF_OP_BGE: + case DIF_OP_BGEU: + case DIF_OP_BL: + case DIF_OP_BLU: + case DIF_OP_BLE: + case DIF_OP_BLEU: + if (label >= dp->dtdo_len) { + err += efunc(pc, "invalid branch target %u\n", + label); + } + if (label <= pc) { + err += efunc(pc, "backward branch to %u\n", + label); + } + break; + case DIF_OP_RET: + if (r1 != 0 || r2 != 0) + err += efunc(pc, "non-zero reserved bits\n"); + if (rd >= nregs) + err += efunc(pc, "invalid register %u\n", rd); + break; + case DIF_OP_NOP: + case DIF_OP_POPTS: + case DIF_OP_FLUSHTS: + if (r1 != 0 || r2 != 0 || rd != 0) + err += efunc(pc, "non-zero reserved bits\n"); + break; + case DIF_OP_SETX: + if (DIF_INSTR_INTEGER(instr) >= dp->dtdo_intlen) { + err += efunc(pc, "invalid integer ref %u\n", + DIF_INSTR_INTEGER(instr)); + } + if (rd >= nregs) + err += efunc(pc, "invalid register %u\n", rd); + if (rd == 0) + err += efunc(pc, "cannot write to %r0\n"); + break; + case DIF_OP_SETS: + if (DIF_INSTR_STRING(instr) >= dp->dtdo_strlen) { + err += efunc(pc, "invalid string ref %u\n", + DIF_INSTR_STRING(instr)); + } + if (rd >= nregs) + err += efunc(pc, "invalid register %u\n", rd); + if (rd == 0) + err += efunc(pc, "cannot write to %r0\n"); + break; + case DIF_OP_LDGA: + case DIF_OP_LDTA: + if (r1 > DIF_VAR_ARRAY_MAX) + err += efunc(pc, "invalid array %u\n", r1); + if (r2 >= nregs) + err += efunc(pc, "invalid register %u\n", r2); + if (rd >= nregs) + err += efunc(pc, "invalid register %u\n", rd); + if (rd == 0) + err += efunc(pc, "cannot write to %r0\n"); + break; + case DIF_OP_LDGS: + case DIF_OP_LDTS: + case DIF_OP_LDLS: + case DIF_OP_LDGAA: + case DIF_OP_LDTAA: + if (v < DIF_VAR_OTHER_MIN || v > DIF_VAR_OTHER_MAX) + err += efunc(pc, "invalid variable %u\n", v); + if (rd >= nregs) + err += efunc(pc, "invalid register %u\n", rd); + if (rd == 0) + err += efunc(pc, "cannot write to %r0\n"); + break; + case DIF_OP_STGS: + case DIF_OP_STTS: + case DIF_OP_STLS: + case DIF_OP_STGAA: + case DIF_OP_STTAA: + if (v < DIF_VAR_OTHER_UBASE || v > DIF_VAR_OTHER_MAX) + err += efunc(pc, "invalid variable %u\n", v); + if (rs >= nregs) + err += efunc(pc, "invalid register %u\n", rd); + break; + case DIF_OP_CALL: + if (subr > DIF_SUBR_MAX) + err += efunc(pc, "invalid subr %u\n", subr); + if (rd >= nregs) + err += efunc(pc, "invalid register %u\n", rd); + if (rd == 0) + err += efunc(pc, "cannot write to %r0\n"); + + if (subr == DIF_SUBR_COPYOUT || + subr == DIF_SUBR_COPYOUTSTR) { + dp->dtdo_destructive = 1; + } + + if (subr == DIF_SUBR_GETF) { + /* + * If we have a getf() we need to record that + * in our state. Note that our state can be + * NULL if this is a helper -- but in that + * case, the call to getf() is itself illegal, + * and will be caught (slightly later) when + * the helper is validated. + */ + if (vstate->dtvs_state != NULL) + vstate->dtvs_state->dts_getf++; + } + + break; + case DIF_OP_PUSHTR: + if (type != DIF_TYPE_STRING && type != DIF_TYPE_CTF) + err += efunc(pc, "invalid ref type %u\n", type); + if (r2 >= nregs) + err += efunc(pc, "invalid register %u\n", r2); + if (rs >= nregs) + err += efunc(pc, "invalid register %u\n", rs); + break; + case DIF_OP_PUSHTV: + if (type != DIF_TYPE_CTF) + err += efunc(pc, "invalid val type %u\n", type); + if (r2 >= nregs) + err += efunc(pc, "invalid register %u\n", r2); + if (rs >= nregs) + err += efunc(pc, "invalid register %u\n", rs); + break; + default: + err += efunc(pc, "invalid opcode %u\n", + DIF_INSTR_OP(instr)); + } + } + + if (dp->dtdo_len != 0 && + DIF_INSTR_OP(dp->dtdo_buf[dp->dtdo_len - 1]) != DIF_OP_RET) { + err += efunc(dp->dtdo_len - 1, + "expected 'ret' as last DIF instruction\n"); + } + + if (!(dp->dtdo_rtype.dtdt_flags & (DIF_TF_BYREF | DIF_TF_BYUREF))) { + /* + * If we're not returning by reference, the size must be either + * 0 or the size of one of the base types. + */ + switch (dp->dtdo_rtype.dtdt_size) { + case 0: + case sizeof (uint8_t): + case sizeof (uint16_t): + case sizeof (uint32_t): + case sizeof (uint64_t): + break; + + default: + err += efunc(dp->dtdo_len - 1, "bad return size\n"); + } + } + + for (i = 0; i < dp->dtdo_varlen && err == 0; i++) { + dtrace_difv_t *v = &dp->dtdo_vartab[i], *existing = NULL; + dtrace_diftype_t *vt, *et; + uint_t id, ndx; + + if (v->dtdv_scope != DIFV_SCOPE_GLOBAL && + v->dtdv_scope != DIFV_SCOPE_THREAD && + v->dtdv_scope != DIFV_SCOPE_LOCAL) { + err += efunc(i, "unrecognized variable scope %d\n", + v->dtdv_scope); + break; + } + + if (v->dtdv_kind != DIFV_KIND_ARRAY && + v->dtdv_kind != DIFV_KIND_SCALAR) { + err += efunc(i, "unrecognized variable type %d\n", + v->dtdv_kind); + break; + } + + if ((id = v->dtdv_id) > DIF_VARIABLE_MAX) { + err += efunc(i, "%d exceeds variable id limit\n", id); + break; + } + + if (id < DIF_VAR_OTHER_UBASE) + continue; + + /* + * For user-defined variables, we need to check that this + * definition is identical to any previous definition that we + * encountered. + */ + ndx = id - DIF_VAR_OTHER_UBASE; + + switch (v->dtdv_scope) { + case DIFV_SCOPE_GLOBAL: + if (maxglobal == -1 || ndx > maxglobal) + maxglobal = ndx; + + if (ndx < vstate->dtvs_nglobals) { + dtrace_statvar_t *svar; + + if ((svar = vstate->dtvs_globals[ndx]) != NULL) + existing = &svar->dtsv_var; + } + + break; + + case DIFV_SCOPE_THREAD: + if (maxtlocal == -1 || ndx > maxtlocal) + maxtlocal = ndx; + + if (ndx < vstate->dtvs_ntlocals) + existing = &vstate->dtvs_tlocals[ndx]; + break; + + case DIFV_SCOPE_LOCAL: + if (maxlocal == -1 || ndx > maxlocal) + maxlocal = ndx; + + if (ndx < vstate->dtvs_nlocals) { + dtrace_statvar_t *svar; + + if ((svar = vstate->dtvs_locals[ndx]) != NULL) + existing = &svar->dtsv_var; + } + + break; + } + + vt = &v->dtdv_type; + + if (vt->dtdt_flags & DIF_TF_BYREF) { + if (vt->dtdt_size == 0) { + err += efunc(i, "zero-sized variable\n"); + break; + } + + if ((v->dtdv_scope == DIFV_SCOPE_GLOBAL || + v->dtdv_scope == DIFV_SCOPE_LOCAL) && + vt->dtdt_size > dtrace_statvar_maxsize) { + err += efunc(i, "oversized by-ref static\n"); + break; + } + } + + if (existing == NULL || existing->dtdv_id == 0) + continue; + + ASSERT(existing->dtdv_id == v->dtdv_id); + ASSERT(existing->dtdv_scope == v->dtdv_scope); + + if (existing->dtdv_kind != v->dtdv_kind) + err += efunc(i, "%d changed variable kind\n", id); + + et = &existing->dtdv_type; + + if (vt->dtdt_flags != et->dtdt_flags) { + err += efunc(i, "%d changed variable type flags\n", id); + break; + } + + if (vt->dtdt_size != 0 && vt->dtdt_size != et->dtdt_size) { + err += efunc(i, "%d changed variable type size\n", id); + break; + } + } + + for (pc = 0; pc < dp->dtdo_len && err == 0; pc++) { + dif_instr_t instr = dp->dtdo_buf[pc]; + + uint_t v = DIF_INSTR_VAR(instr); + uint_t op = DIF_INSTR_OP(instr); + + switch (op) { + case DIF_OP_LDGS: + case DIF_OP_LDGAA: + case DIF_OP_STGS: + case DIF_OP_STGAA: + if (v > DIF_VAR_OTHER_UBASE + maxglobal) + err += efunc(pc, "invalid variable %u\n", v); + break; + case DIF_OP_LDTS: + case DIF_OP_LDTAA: + case DIF_OP_STTS: + case DIF_OP_STTAA: + if (v > DIF_VAR_OTHER_UBASE + maxtlocal) + err += efunc(pc, "invalid variable %u\n", v); + break; + case DIF_OP_LDLS: + case DIF_OP_STLS: + if (v > DIF_VAR_OTHER_UBASE + maxlocal) + err += efunc(pc, "invalid variable %u\n", v); + break; + default: + break; + } + } + + return (err); +} + +/* + * Validate a DTrace DIF object that it is to be used as a helper. Helpers + * are much more constrained than normal DIFOs. Specifically, they may + * not: + * + * 1. Make calls to subroutines other than copyin(), copyinstr() or + * miscellaneous string routines + * 2. Access DTrace variables other than the args[] array, and the + * curthread, pid, ppid, tid, execname, zonename, uid and gid variables. + * 3. Have thread-local variables. + * 4. Have dynamic variables. + */ +static int +dtrace_difo_validate_helper(dtrace_difo_t *dp) +{ + int (*efunc)(uint_t pc, const char *, ...) = dtrace_difo_err; + int err = 0; + uint_t pc; + + for (pc = 0; pc < dp->dtdo_len; pc++) { + dif_instr_t instr = dp->dtdo_buf[pc]; + + uint_t v = DIF_INSTR_VAR(instr); + uint_t subr = DIF_INSTR_SUBR(instr); + uint_t op = DIF_INSTR_OP(instr); + + switch (op) { + case DIF_OP_OR: + case DIF_OP_XOR: + case DIF_OP_AND: + case DIF_OP_SLL: + case DIF_OP_SRL: + case DIF_OP_SRA: + case DIF_OP_SUB: + case DIF_OP_ADD: + case DIF_OP_MUL: + case DIF_OP_SDIV: + case DIF_OP_UDIV: + case DIF_OP_SREM: + case DIF_OP_UREM: + case DIF_OP_COPYS: + case DIF_OP_NOT: + case DIF_OP_MOV: + case DIF_OP_RLDSB: + case DIF_OP_RLDSH: + case DIF_OP_RLDSW: + case DIF_OP_RLDUB: + case DIF_OP_RLDUH: + case DIF_OP_RLDUW: + case DIF_OP_RLDX: + case DIF_OP_ULDSB: + case DIF_OP_ULDSH: + case DIF_OP_ULDSW: + case DIF_OP_ULDUB: + case DIF_OP_ULDUH: + case DIF_OP_ULDUW: + case DIF_OP_ULDX: + case DIF_OP_STB: + case DIF_OP_STH: + case DIF_OP_STW: + case DIF_OP_STX: + case DIF_OP_ALLOCS: + case DIF_OP_CMP: + case DIF_OP_SCMP: + case DIF_OP_TST: + case DIF_OP_BA: + case DIF_OP_BE: + case DIF_OP_BNE: + case DIF_OP_BG: + case DIF_OP_BGU: + case DIF_OP_BGE: + case DIF_OP_BGEU: + case DIF_OP_BL: + case DIF_OP_BLU: + case DIF_OP_BLE: + case DIF_OP_BLEU: + case DIF_OP_RET: + case DIF_OP_NOP: + case DIF_OP_POPTS: + case DIF_OP_FLUSHTS: + case DIF_OP_SETX: + case DIF_OP_SETS: + case DIF_OP_LDGA: + case DIF_OP_LDLS: + case DIF_OP_STGS: + case DIF_OP_STLS: + case DIF_OP_PUSHTR: + case DIF_OP_PUSHTV: + break; + + case DIF_OP_LDGS: + if (v >= DIF_VAR_OTHER_UBASE) + break; + + if (v >= DIF_VAR_ARG0 && v <= DIF_VAR_ARG9) + break; + + if (v == DIF_VAR_CURTHREAD || v == DIF_VAR_PID || + v == DIF_VAR_PPID || v == DIF_VAR_TID || + v == DIF_VAR_EXECARGS || + v == DIF_VAR_EXECNAME || v == DIF_VAR_ZONENAME || + v == DIF_VAR_UID || v == DIF_VAR_GID) + break; + + err += efunc(pc, "illegal variable %u\n", v); + break; + + case DIF_OP_LDTA: + case DIF_OP_LDTS: + case DIF_OP_LDGAA: + case DIF_OP_LDTAA: + err += efunc(pc, "illegal dynamic variable load\n"); + break; + + case DIF_OP_STTS: + case DIF_OP_STGAA: + case DIF_OP_STTAA: + err += efunc(pc, "illegal dynamic variable store\n"); + break; + + case DIF_OP_CALL: + if (subr == DIF_SUBR_ALLOCA || + subr == DIF_SUBR_BCOPY || + subr == DIF_SUBR_COPYIN || + subr == DIF_SUBR_COPYINTO || + subr == DIF_SUBR_COPYINSTR || + subr == DIF_SUBR_INDEX || + subr == DIF_SUBR_INET_NTOA || + subr == DIF_SUBR_INET_NTOA6 || + subr == DIF_SUBR_INET_NTOP || + subr == DIF_SUBR_JSON || + subr == DIF_SUBR_LLTOSTR || + subr == DIF_SUBR_STRTOLL || + subr == DIF_SUBR_RINDEX || + subr == DIF_SUBR_STRCHR || + subr == DIF_SUBR_STRJOIN || + subr == DIF_SUBR_STRRCHR || + subr == DIF_SUBR_STRSTR || + subr == DIF_SUBR_HTONS || + subr == DIF_SUBR_HTONL || + subr == DIF_SUBR_HTONLL || + subr == DIF_SUBR_NTOHS || + subr == DIF_SUBR_NTOHL || + subr == DIF_SUBR_NTOHLL || + subr == DIF_SUBR_MEMREF) + break; +#ifdef __FreeBSD__ + if (subr == DIF_SUBR_MEMSTR) + break; +#endif + + err += efunc(pc, "invalid subr %u\n", subr); + break; + + default: + err += efunc(pc, "invalid opcode %u\n", + DIF_INSTR_OP(instr)); + } + } + + return (err); +} + +/* + * Returns 1 if the expression in the DIF object can be cached on a per-thread + * basis; 0 if not. + */ +static int +dtrace_difo_cacheable(dtrace_difo_t *dp) +{ + int i; + + if (dp == NULL) + return (0); + + for (i = 0; i < dp->dtdo_varlen; i++) { + dtrace_difv_t *v = &dp->dtdo_vartab[i]; + + if (v->dtdv_scope != DIFV_SCOPE_GLOBAL) + continue; + + switch (v->dtdv_id) { + case DIF_VAR_CURTHREAD: + case DIF_VAR_PID: + case DIF_VAR_TID: + case DIF_VAR_EXECARGS: + case DIF_VAR_EXECNAME: + case DIF_VAR_ZONENAME: + break; + + default: + return (0); + } + } + + /* + * This DIF object may be cacheable. Now we need to look for any + * array loading instructions, any memory loading instructions, or + * any stores to thread-local variables. + */ + for (i = 0; i < dp->dtdo_len; i++) { + uint_t op = DIF_INSTR_OP(dp->dtdo_buf[i]); + + if ((op >= DIF_OP_LDSB && op <= DIF_OP_LDX) || + (op >= DIF_OP_ULDSB && op <= DIF_OP_ULDX) || + (op >= DIF_OP_RLDSB && op <= DIF_OP_RLDX) || + op == DIF_OP_LDGA || op == DIF_OP_STTS) + return (0); + } + + return (1); +} + +static void +dtrace_difo_hold(dtrace_difo_t *dp) +{ + int i; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + + dp->dtdo_refcnt++; + ASSERT(dp->dtdo_refcnt != 0); + + /* + * We need to check this DIF object for references to the variable + * DIF_VAR_VTIMESTAMP. + */ + for (i = 0; i < dp->dtdo_varlen; i++) { + dtrace_difv_t *v = &dp->dtdo_vartab[i]; + + if (v->dtdv_id != DIF_VAR_VTIMESTAMP) + continue; + + if (dtrace_vtime_references++ == 0) + dtrace_vtime_enable(); + } +} + +/* + * This routine calculates the dynamic variable chunksize for a given DIF + * object. The calculation is not fool-proof, and can probably be tricked by + * malicious DIF -- but it works for all compiler-generated DIF. Because this + * calculation is likely imperfect, dtrace_dynvar() is able to gracefully fail + * if a dynamic variable size exceeds the chunksize. + */ +static void +dtrace_difo_chunksize(dtrace_difo_t *dp, dtrace_vstate_t *vstate) +{ + uint64_t sval = 0; + dtrace_key_t tupregs[DIF_DTR_NREGS + 2]; /* +2 for thread and id */ + const dif_instr_t *text = dp->dtdo_buf; + uint_t pc, srd = 0; + uint_t ttop = 0; + size_t size, ksize; + uint_t id, i; + + for (pc = 0; pc < dp->dtdo_len; pc++) { + dif_instr_t instr = text[pc]; + uint_t op = DIF_INSTR_OP(instr); + uint_t rd = DIF_INSTR_RD(instr); + uint_t r1 = DIF_INSTR_R1(instr); + uint_t nkeys = 0; + uchar_t scope = 0; + + dtrace_key_t *key = tupregs; + + switch (op) { + case DIF_OP_SETX: + sval = dp->dtdo_inttab[DIF_INSTR_INTEGER(instr)]; + srd = rd; + continue; + + case DIF_OP_STTS: + key = &tupregs[DIF_DTR_NREGS]; + key[0].dttk_size = 0; + key[1].dttk_size = 0; + nkeys = 2; + scope = DIFV_SCOPE_THREAD; + break; + + case DIF_OP_STGAA: + case DIF_OP_STTAA: + nkeys = ttop; + + if (DIF_INSTR_OP(instr) == DIF_OP_STTAA) + key[nkeys++].dttk_size = 0; + + key[nkeys++].dttk_size = 0; + + if (op == DIF_OP_STTAA) { + scope = DIFV_SCOPE_THREAD; + } else { + scope = DIFV_SCOPE_GLOBAL; + } + + break; + + case DIF_OP_PUSHTR: + if (ttop == DIF_DTR_NREGS) + return; + + if ((srd == 0 || sval == 0) && r1 == DIF_TYPE_STRING) { + /* + * If the register for the size of the "pushtr" + * is %r0 (or the value is 0) and the type is + * a string, we'll use the system-wide default + * string size. + */ + tupregs[ttop++].dttk_size = + dtrace_strsize_default; + } else { + if (srd == 0) + return; + + if (sval > LONG_MAX) + return; + + tupregs[ttop++].dttk_size = sval; + } + + break; + + case DIF_OP_PUSHTV: + if (ttop == DIF_DTR_NREGS) + return; + + tupregs[ttop++].dttk_size = 0; + break; + + case DIF_OP_FLUSHTS: + ttop = 0; + break; + + case DIF_OP_POPTS: + if (ttop != 0) + ttop--; + break; + } + + sval = 0; + srd = 0; + + if (nkeys == 0) + continue; + + /* + * We have a dynamic variable allocation; calculate its size. + */ + for (ksize = 0, i = 0; i < nkeys; i++) + ksize += P2ROUNDUP(key[i].dttk_size, sizeof (uint64_t)); + + size = sizeof (dtrace_dynvar_t); + size += sizeof (dtrace_key_t) * (nkeys - 1); + size += ksize; + + /* + * Now we need to determine the size of the stored data. + */ + id = DIF_INSTR_VAR(instr); + + for (i = 0; i < dp->dtdo_varlen; i++) { + dtrace_difv_t *v = &dp->dtdo_vartab[i]; + + if (v->dtdv_id == id && v->dtdv_scope == scope) { + size += v->dtdv_type.dtdt_size; + break; + } + } + + if (i == dp->dtdo_varlen) + return; + + /* + * We have the size. If this is larger than the chunk size + * for our dynamic variable state, reset the chunk size. + */ + size = P2ROUNDUP(size, sizeof (uint64_t)); + + /* + * Before setting the chunk size, check that we're not going + * to set it to a negative value... + */ + if (size > LONG_MAX) + return; + + /* + * ...and make certain that we didn't badly overflow. + */ + if (size < ksize || size < sizeof (dtrace_dynvar_t)) + return; + + if (size > vstate->dtvs_dynvars.dtds_chunksize) + vstate->dtvs_dynvars.dtds_chunksize = size; + } +} + +static void +dtrace_difo_init(dtrace_difo_t *dp, dtrace_vstate_t *vstate) +{ + int i, oldsvars, osz, nsz, otlocals, ntlocals; + uint_t id; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(dp->dtdo_buf != NULL && dp->dtdo_len != 0); + + for (i = 0; i < dp->dtdo_varlen; i++) { + dtrace_difv_t *v = &dp->dtdo_vartab[i]; + dtrace_statvar_t *svar, ***svarp = NULL; + size_t dsize = 0; + uint8_t scope = v->dtdv_scope; + int *np = NULL; + + if ((id = v->dtdv_id) < DIF_VAR_OTHER_UBASE) + continue; + + id -= DIF_VAR_OTHER_UBASE; + + switch (scope) { + case DIFV_SCOPE_THREAD: + while (id >= (otlocals = vstate->dtvs_ntlocals)) { + dtrace_difv_t *tlocals; + + if ((ntlocals = (otlocals << 1)) == 0) + ntlocals = 1; + + osz = otlocals * sizeof (dtrace_difv_t); + nsz = ntlocals * sizeof (dtrace_difv_t); + + tlocals = kmem_zalloc(nsz, KM_SLEEP); + + if (osz != 0) { + bcopy(vstate->dtvs_tlocals, + tlocals, osz); + kmem_free(vstate->dtvs_tlocals, osz); + } + + vstate->dtvs_tlocals = tlocals; + vstate->dtvs_ntlocals = ntlocals; + } + + vstate->dtvs_tlocals[id] = *v; + continue; + + case DIFV_SCOPE_LOCAL: + np = &vstate->dtvs_nlocals; + svarp = &vstate->dtvs_locals; + + if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) + dsize = NCPU * (v->dtdv_type.dtdt_size + + sizeof (uint64_t)); + else + dsize = NCPU * sizeof (uint64_t); + + break; + + case DIFV_SCOPE_GLOBAL: + np = &vstate->dtvs_nglobals; + svarp = &vstate->dtvs_globals; + + if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) + dsize = v->dtdv_type.dtdt_size + + sizeof (uint64_t); + + break; + + default: + ASSERT(0); + } + + while (id >= (oldsvars = *np)) { + dtrace_statvar_t **statics; + int newsvars, oldsize, newsize; + + if ((newsvars = (oldsvars << 1)) == 0) + newsvars = 1; + + oldsize = oldsvars * sizeof (dtrace_statvar_t *); + newsize = newsvars * sizeof (dtrace_statvar_t *); + + statics = kmem_zalloc(newsize, KM_SLEEP); + + if (oldsize != 0) { + bcopy(*svarp, statics, oldsize); + kmem_free(*svarp, oldsize); + } + + *svarp = statics; + *np = newsvars; + } + + if ((svar = (*svarp)[id]) == NULL) { + svar = kmem_zalloc(sizeof (dtrace_statvar_t), KM_SLEEP); + svar->dtsv_var = *v; + + if ((svar->dtsv_size = dsize) != 0) { + svar->dtsv_data = (uint64_t)(uintptr_t) + kmem_zalloc(dsize, KM_SLEEP); + } + + (*svarp)[id] = svar; + } + + svar->dtsv_refcnt++; + } + + dtrace_difo_chunksize(dp, vstate); + dtrace_difo_hold(dp); +} + +static dtrace_difo_t * +dtrace_difo_duplicate(dtrace_difo_t *dp, dtrace_vstate_t *vstate) +{ + dtrace_difo_t *new; + size_t sz; + + ASSERT(dp->dtdo_buf != NULL); + ASSERT(dp->dtdo_refcnt != 0); + + new = kmem_zalloc(sizeof (dtrace_difo_t), KM_SLEEP); + + ASSERT(dp->dtdo_buf != NULL); + sz = dp->dtdo_len * sizeof (dif_instr_t); + new->dtdo_buf = kmem_alloc(sz, KM_SLEEP); + bcopy(dp->dtdo_buf, new->dtdo_buf, sz); + new->dtdo_len = dp->dtdo_len; + + if (dp->dtdo_strtab != NULL) { + ASSERT(dp->dtdo_strlen != 0); + new->dtdo_strtab = kmem_alloc(dp->dtdo_strlen, KM_SLEEP); + bcopy(dp->dtdo_strtab, new->dtdo_strtab, dp->dtdo_strlen); + new->dtdo_strlen = dp->dtdo_strlen; + } + + if (dp->dtdo_inttab != NULL) { + ASSERT(dp->dtdo_intlen != 0); + sz = dp->dtdo_intlen * sizeof (uint64_t); + new->dtdo_inttab = kmem_alloc(sz, KM_SLEEP); + bcopy(dp->dtdo_inttab, new->dtdo_inttab, sz); + new->dtdo_intlen = dp->dtdo_intlen; + } + + if (dp->dtdo_vartab != NULL) { + ASSERT(dp->dtdo_varlen != 0); + sz = dp->dtdo_varlen * sizeof (dtrace_difv_t); + new->dtdo_vartab = kmem_alloc(sz, KM_SLEEP); + bcopy(dp->dtdo_vartab, new->dtdo_vartab, sz); + new->dtdo_varlen = dp->dtdo_varlen; + } + + dtrace_difo_init(new, vstate); + return (new); +} + +static void +dtrace_difo_destroy(dtrace_difo_t *dp, dtrace_vstate_t *vstate) +{ + int i; + + ASSERT(dp->dtdo_refcnt == 0); + + for (i = 0; i < dp->dtdo_varlen; i++) { + dtrace_difv_t *v = &dp->dtdo_vartab[i]; + dtrace_statvar_t *svar, **svarp = NULL; + uint_t id; + uint8_t scope = v->dtdv_scope; + int *np = NULL; + + switch (scope) { + case DIFV_SCOPE_THREAD: + continue; + + case DIFV_SCOPE_LOCAL: + np = &vstate->dtvs_nlocals; + svarp = vstate->dtvs_locals; + break; + + case DIFV_SCOPE_GLOBAL: + np = &vstate->dtvs_nglobals; + svarp = vstate->dtvs_globals; + break; + + default: + ASSERT(0); + } + + if ((id = v->dtdv_id) < DIF_VAR_OTHER_UBASE) + continue; + + id -= DIF_VAR_OTHER_UBASE; + ASSERT(id < *np); + + svar = svarp[id]; + ASSERT(svar != NULL); + ASSERT(svar->dtsv_refcnt > 0); + + if (--svar->dtsv_refcnt > 0) + continue; + + if (svar->dtsv_size != 0) { + ASSERT(svar->dtsv_data != 0); + kmem_free((void *)(uintptr_t)svar->dtsv_data, + svar->dtsv_size); + } + + kmem_free(svar, sizeof (dtrace_statvar_t)); + svarp[id] = NULL; + } + + if (dp->dtdo_buf != NULL) + kmem_free(dp->dtdo_buf, dp->dtdo_len * sizeof (dif_instr_t)); + if (dp->dtdo_inttab != NULL) + kmem_free(dp->dtdo_inttab, dp->dtdo_intlen * sizeof (uint64_t)); + if (dp->dtdo_strtab != NULL) + kmem_free(dp->dtdo_strtab, dp->dtdo_strlen); + if (dp->dtdo_vartab != NULL) + kmem_free(dp->dtdo_vartab, dp->dtdo_varlen * sizeof (dtrace_difv_t)); + + kmem_free(dp, sizeof (dtrace_difo_t)); +} + +static void +dtrace_difo_release(dtrace_difo_t *dp, dtrace_vstate_t *vstate) +{ + int i; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(dp->dtdo_refcnt != 0); + + for (i = 0; i < dp->dtdo_varlen; i++) { + dtrace_difv_t *v = &dp->dtdo_vartab[i]; + + if (v->dtdv_id != DIF_VAR_VTIMESTAMP) + continue; + + ASSERT(dtrace_vtime_references > 0); + if (--dtrace_vtime_references == 0) + dtrace_vtime_disable(); + } + + if (--dp->dtdo_refcnt == 0) + dtrace_difo_destroy(dp, vstate); +} + +/* + * DTrace Format Functions + */ +static uint16_t +dtrace_format_add(dtrace_state_t *state, char *str) +{ + char *fmt, **new; + uint16_t ndx, len = strlen(str) + 1; + + fmt = kmem_zalloc(len, KM_SLEEP); + bcopy(str, fmt, len); + + for (ndx = 0; ndx < state->dts_nformats; ndx++) { + if (state->dts_formats[ndx] == NULL) { + state->dts_formats[ndx] = fmt; + return (ndx + 1); + } + } + + if (state->dts_nformats == USHRT_MAX) { + /* + * This is only likely if a denial-of-service attack is being + * attempted. As such, it's okay to fail silently here. + */ + kmem_free(fmt, len); + return (0); + } + + /* + * For simplicity, we always resize the formats array to be exactly the + * number of formats. + */ + ndx = state->dts_nformats++; + new = kmem_alloc((ndx + 1) * sizeof (char *), KM_SLEEP); + + if (state->dts_formats != NULL) { + ASSERT(ndx != 0); + bcopy(state->dts_formats, new, ndx * sizeof (char *)); + kmem_free(state->dts_formats, ndx * sizeof (char *)); + } + + state->dts_formats = new; + state->dts_formats[ndx] = fmt; + + return (ndx + 1); +} + +static void +dtrace_format_remove(dtrace_state_t *state, uint16_t format) +{ + char *fmt; + + ASSERT(state->dts_formats != NULL); + ASSERT(format <= state->dts_nformats); + ASSERT(state->dts_formats[format - 1] != NULL); + + fmt = state->dts_formats[format - 1]; + kmem_free(fmt, strlen(fmt) + 1); + state->dts_formats[format - 1] = NULL; +} + +static void +dtrace_format_destroy(dtrace_state_t *state) +{ + int i; + + if (state->dts_nformats == 0) { + ASSERT(state->dts_formats == NULL); + return; + } + + ASSERT(state->dts_formats != NULL); + + for (i = 0; i < state->dts_nformats; i++) { + char *fmt = state->dts_formats[i]; + + if (fmt == NULL) + continue; + + kmem_free(fmt, strlen(fmt) + 1); + } + + kmem_free(state->dts_formats, state->dts_nformats * sizeof (char *)); + state->dts_nformats = 0; + state->dts_formats = NULL; +} + +/* + * DTrace Predicate Functions + */ +static dtrace_predicate_t * +dtrace_predicate_create(dtrace_difo_t *dp) +{ + dtrace_predicate_t *pred; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(dp->dtdo_refcnt != 0); + + pred = kmem_zalloc(sizeof (dtrace_predicate_t), KM_SLEEP); + pred->dtp_difo = dp; + pred->dtp_refcnt = 1; + + if (!dtrace_difo_cacheable(dp)) + return (pred); + + if (dtrace_predcache_id == DTRACE_CACHEIDNONE) { + /* + * This is only theoretically possible -- we have had 2^32 + * cacheable predicates on this machine. We cannot allow any + * more predicates to become cacheable: as unlikely as it is, + * there may be a thread caching a (now stale) predicate cache + * ID. (N.B.: the temptation is being successfully resisted to + * have this cmn_err() "Holy shit -- we executed this code!") + */ + return (pred); + } + + pred->dtp_cacheid = dtrace_predcache_id++; + + return (pred); +} + +static void +dtrace_predicate_hold(dtrace_predicate_t *pred) +{ + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(pred->dtp_difo != NULL && pred->dtp_difo->dtdo_refcnt != 0); + ASSERT(pred->dtp_refcnt > 0); + + pred->dtp_refcnt++; +} + +static void +dtrace_predicate_release(dtrace_predicate_t *pred, dtrace_vstate_t *vstate) +{ + dtrace_difo_t *dp = pred->dtp_difo; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(dp != NULL && dp->dtdo_refcnt != 0); + ASSERT(pred->dtp_refcnt > 0); + + if (--pred->dtp_refcnt == 0) { + dtrace_difo_release(pred->dtp_difo, vstate); + kmem_free(pred, sizeof (dtrace_predicate_t)); + } +} + +/* + * DTrace Action Description Functions + */ +static dtrace_actdesc_t * +dtrace_actdesc_create(dtrace_actkind_t kind, uint32_t ntuple, + uint64_t uarg, uint64_t arg) +{ + dtrace_actdesc_t *act; + +#ifdef illumos + ASSERT(!DTRACEACT_ISPRINTFLIKE(kind) || (arg != NULL && + arg >= KERNELBASE) || (arg == NULL && kind == DTRACEACT_PRINTA)); +#endif + + act = kmem_zalloc(sizeof (dtrace_actdesc_t), KM_SLEEP); + act->dtad_kind = kind; + act->dtad_ntuple = ntuple; + act->dtad_uarg = uarg; + act->dtad_arg = arg; + act->dtad_refcnt = 1; + + return (act); +} + +static void +dtrace_actdesc_hold(dtrace_actdesc_t *act) +{ + ASSERT(act->dtad_refcnt >= 1); + act->dtad_refcnt++; +} + +static void +dtrace_actdesc_release(dtrace_actdesc_t *act, dtrace_vstate_t *vstate) +{ + dtrace_actkind_t kind = act->dtad_kind; + dtrace_difo_t *dp; + + ASSERT(act->dtad_refcnt >= 1); + + if (--act->dtad_refcnt != 0) + return; + + if ((dp = act->dtad_difo) != NULL) + dtrace_difo_release(dp, vstate); + + if (DTRACEACT_ISPRINTFLIKE(kind)) { + char *str = (char *)(uintptr_t)act->dtad_arg; + +#ifdef illumos + ASSERT((str != NULL && (uintptr_t)str >= KERNELBASE) || + (str == NULL && act->dtad_kind == DTRACEACT_PRINTA)); +#endif + + if (str != NULL) + kmem_free(str, strlen(str) + 1); + } + + kmem_free(act, sizeof (dtrace_actdesc_t)); +} + +/* + * DTrace ECB Functions + */ +static dtrace_ecb_t * +dtrace_ecb_add(dtrace_state_t *state, dtrace_probe_t *probe) +{ + dtrace_ecb_t *ecb; + dtrace_epid_t epid; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + + ecb = kmem_zalloc(sizeof (dtrace_ecb_t), KM_SLEEP); + ecb->dte_predicate = NULL; + ecb->dte_probe = probe; + + /* + * The default size is the size of the default action: recording + * the header. + */ + ecb->dte_size = ecb->dte_needed = sizeof (dtrace_rechdr_t); + ecb->dte_alignment = sizeof (dtrace_epid_t); + + epid = state->dts_epid++; + + if (epid - 1 >= state->dts_necbs) { + dtrace_ecb_t **oecbs = state->dts_ecbs, **ecbs; + int necbs = state->dts_necbs << 1; + + ASSERT(epid == state->dts_necbs + 1); + + if (necbs == 0) { + ASSERT(oecbs == NULL); + necbs = 1; + } + + ecbs = kmem_zalloc(necbs * sizeof (*ecbs), KM_SLEEP); + + if (oecbs != NULL) + bcopy(oecbs, ecbs, state->dts_necbs * sizeof (*ecbs)); + + dtrace_membar_producer(); + state->dts_ecbs = ecbs; + + if (oecbs != NULL) { + /* + * If this state is active, we must dtrace_sync() + * before we can free the old dts_ecbs array: we're + * coming in hot, and there may be active ring + * buffer processing (which indexes into the dts_ecbs + * array) on another CPU. + */ + if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE) + dtrace_sync(); + + kmem_free(oecbs, state->dts_necbs * sizeof (*ecbs)); + } + + dtrace_membar_producer(); + state->dts_necbs = necbs; + } + + ecb->dte_state = state; + + ASSERT(state->dts_ecbs[epid - 1] == NULL); + dtrace_membar_producer(); + state->dts_ecbs[(ecb->dte_epid = epid) - 1] = ecb; + + return (ecb); +} + +static void +dtrace_ecb_enable(dtrace_ecb_t *ecb) +{ + dtrace_probe_t *probe = ecb->dte_probe; + + ASSERT(MUTEX_HELD(&cpu_lock)); + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(ecb->dte_next == NULL); + + if (probe == NULL) { + /* + * This is the NULL probe -- there's nothing to do. + */ + return; + } + + if (probe->dtpr_ecb == NULL) { + dtrace_provider_t *prov = probe->dtpr_provider; + + /* + * We're the first ECB on this probe. + */ + probe->dtpr_ecb = probe->dtpr_ecb_last = ecb; + + if (ecb->dte_predicate != NULL) + probe->dtpr_predcache = ecb->dte_predicate->dtp_cacheid; + + prov->dtpv_pops.dtps_enable(prov->dtpv_arg, + probe->dtpr_id, probe->dtpr_arg); + } else { + /* + * This probe is already active. Swing the last pointer to + * point to the new ECB, and issue a dtrace_sync() to assure + * that all CPUs have seen the change. + */ + ASSERT(probe->dtpr_ecb_last != NULL); + probe->dtpr_ecb_last->dte_next = ecb; + probe->dtpr_ecb_last = ecb; + probe->dtpr_predcache = 0; + + dtrace_sync(); + } +} + +static int +dtrace_ecb_resize(dtrace_ecb_t *ecb) +{ + dtrace_action_t *act; + uint32_t curneeded = UINT32_MAX; + uint32_t aggbase = UINT32_MAX; + + /* + * If we record anything, we always record the dtrace_rechdr_t. (And + * we always record it first.) + */ + ecb->dte_size = sizeof (dtrace_rechdr_t); + ecb->dte_alignment = sizeof (dtrace_epid_t); + + for (act = ecb->dte_action; act != NULL; act = act->dta_next) { + dtrace_recdesc_t *rec = &act->dta_rec; + ASSERT(rec->dtrd_size > 0 || rec->dtrd_alignment == 1); + + ecb->dte_alignment = MAX(ecb->dte_alignment, + rec->dtrd_alignment); + + if (DTRACEACT_ISAGG(act->dta_kind)) { + dtrace_aggregation_t *agg = (dtrace_aggregation_t *)act; + + ASSERT(rec->dtrd_size != 0); + ASSERT(agg->dtag_first != NULL); + ASSERT(act->dta_prev->dta_intuple); + ASSERT(aggbase != UINT32_MAX); + ASSERT(curneeded != UINT32_MAX); + + agg->dtag_base = aggbase; + + curneeded = P2ROUNDUP(curneeded, rec->dtrd_alignment); + rec->dtrd_offset = curneeded; + if (curneeded + rec->dtrd_size < curneeded) + return (EINVAL); + curneeded += rec->dtrd_size; + ecb->dte_needed = MAX(ecb->dte_needed, curneeded); + + aggbase = UINT32_MAX; + curneeded = UINT32_MAX; + } else if (act->dta_intuple) { + if (curneeded == UINT32_MAX) { + /* + * This is the first record in a tuple. Align + * curneeded to be at offset 4 in an 8-byte + * aligned block. + */ + ASSERT(act->dta_prev == NULL || + !act->dta_prev->dta_intuple); + ASSERT3U(aggbase, ==, UINT32_MAX); + curneeded = P2PHASEUP(ecb->dte_size, + sizeof (uint64_t), sizeof (dtrace_aggid_t)); + + aggbase = curneeded - sizeof (dtrace_aggid_t); + ASSERT(IS_P2ALIGNED(aggbase, + sizeof (uint64_t))); + } + curneeded = P2ROUNDUP(curneeded, rec->dtrd_alignment); + rec->dtrd_offset = curneeded; + if (curneeded + rec->dtrd_size < curneeded) + return (EINVAL); + curneeded += rec->dtrd_size; + } else { + /* tuples must be followed by an aggregation */ + ASSERT(act->dta_prev == NULL || + !act->dta_prev->dta_intuple); + + ecb->dte_size = P2ROUNDUP(ecb->dte_size, + rec->dtrd_alignment); + rec->dtrd_offset = ecb->dte_size; + if (ecb->dte_size + rec->dtrd_size < ecb->dte_size) + return (EINVAL); + ecb->dte_size += rec->dtrd_size; + ecb->dte_needed = MAX(ecb->dte_needed, ecb->dte_size); + } + } + + if ((act = ecb->dte_action) != NULL && + !(act->dta_kind == DTRACEACT_SPECULATE && act->dta_next == NULL) && + ecb->dte_size == sizeof (dtrace_rechdr_t)) { + /* + * If the size is still sizeof (dtrace_rechdr_t), then all + * actions store no data; set the size to 0. + */ + ecb->dte_size = 0; + } + + ecb->dte_size = P2ROUNDUP(ecb->dte_size, sizeof (dtrace_epid_t)); + ecb->dte_needed = P2ROUNDUP(ecb->dte_needed, (sizeof (dtrace_epid_t))); + ecb->dte_state->dts_needed = MAX(ecb->dte_state->dts_needed, + ecb->dte_needed); + return (0); +} + +static dtrace_action_t * +dtrace_ecb_aggregation_create(dtrace_ecb_t *ecb, dtrace_actdesc_t *desc) +{ + dtrace_aggregation_t *agg; + size_t size = sizeof (uint64_t); + int ntuple = desc->dtad_ntuple; + dtrace_action_t *act; + dtrace_recdesc_t *frec; + dtrace_aggid_t aggid; + dtrace_state_t *state = ecb->dte_state; + + agg = kmem_zalloc(sizeof (dtrace_aggregation_t), KM_SLEEP); + agg->dtag_ecb = ecb; + + ASSERT(DTRACEACT_ISAGG(desc->dtad_kind)); + + switch (desc->dtad_kind) { + case DTRACEAGG_MIN: + agg->dtag_initial = INT64_MAX; + agg->dtag_aggregate = dtrace_aggregate_min; + break; + + case DTRACEAGG_MAX: + agg->dtag_initial = INT64_MIN; + agg->dtag_aggregate = dtrace_aggregate_max; + break; + + case DTRACEAGG_COUNT: + agg->dtag_aggregate = dtrace_aggregate_count; + break; + + case DTRACEAGG_QUANTIZE: + agg->dtag_aggregate = dtrace_aggregate_quantize; + size = (((sizeof (uint64_t) * NBBY) - 1) * 2 + 1) * + sizeof (uint64_t); + break; + + case DTRACEAGG_LQUANTIZE: { + uint16_t step = DTRACE_LQUANTIZE_STEP(desc->dtad_arg); + uint16_t levels = DTRACE_LQUANTIZE_LEVELS(desc->dtad_arg); + + agg->dtag_initial = desc->dtad_arg; + agg->dtag_aggregate = dtrace_aggregate_lquantize; + + if (step == 0 || levels == 0) + goto err; + + size = levels * sizeof (uint64_t) + 3 * sizeof (uint64_t); + break; + } + + case DTRACEAGG_LLQUANTIZE: { + uint16_t factor = DTRACE_LLQUANTIZE_FACTOR(desc->dtad_arg); + uint16_t low = DTRACE_LLQUANTIZE_LOW(desc->dtad_arg); + uint16_t high = DTRACE_LLQUANTIZE_HIGH(desc->dtad_arg); + uint16_t nsteps = DTRACE_LLQUANTIZE_NSTEP(desc->dtad_arg); + int64_t v; + + agg->dtag_initial = desc->dtad_arg; + agg->dtag_aggregate = dtrace_aggregate_llquantize; + + if (factor < 2 || low >= high || nsteps < factor) + goto err; + + /* + * Now check that the number of steps evenly divides a power + * of the factor. (This assures both integer bucket size and + * linearity within each magnitude.) + */ + for (v = factor; v < nsteps; v *= factor) + continue; + + if ((v % nsteps) || (nsteps % factor)) + goto err; + + size = (dtrace_aggregate_llquantize_bucket(factor, + low, high, nsteps, INT64_MAX) + 2) * sizeof (uint64_t); + break; + } + + case DTRACEAGG_AVG: + agg->dtag_aggregate = dtrace_aggregate_avg; + size = sizeof (uint64_t) * 2; + break; + + case DTRACEAGG_STDDEV: + agg->dtag_aggregate = dtrace_aggregate_stddev; + size = sizeof (uint64_t) * 4; + break; + + case DTRACEAGG_SUM: + agg->dtag_aggregate = dtrace_aggregate_sum; + break; + + default: + goto err; + } + + agg->dtag_action.dta_rec.dtrd_size = size; + + if (ntuple == 0) + goto err; + + /* + * We must make sure that we have enough actions for the n-tuple. + */ + for (act = ecb->dte_action_last; act != NULL; act = act->dta_prev) { + if (DTRACEACT_ISAGG(act->dta_kind)) + break; + + if (--ntuple == 0) { + /* + * This is the action with which our n-tuple begins. + */ + agg->dtag_first = act; + goto success; + } + } + + /* + * This n-tuple is short by ntuple elements. Return failure. + */ + ASSERT(ntuple != 0); +err: + kmem_free(agg, sizeof (dtrace_aggregation_t)); + return (NULL); + +success: + /* + * If the last action in the tuple has a size of zero, it's actually + * an expression argument for the aggregating action. + */ + ASSERT(ecb->dte_action_last != NULL); + act = ecb->dte_action_last; + + if (act->dta_kind == DTRACEACT_DIFEXPR) { + ASSERT(act->dta_difo != NULL); + + if (act->dta_difo->dtdo_rtype.dtdt_size == 0) + agg->dtag_hasarg = 1; + } + + /* + * We need to allocate an id for this aggregation. + */ +#ifdef illumos + aggid = (dtrace_aggid_t)(uintptr_t)vmem_alloc(state->dts_aggid_arena, 1, + VM_BESTFIT | VM_SLEEP); +#else + aggid = alloc_unr(state->dts_aggid_arena); +#endif + + if (aggid - 1 >= state->dts_naggregations) { + dtrace_aggregation_t **oaggs = state->dts_aggregations; + dtrace_aggregation_t **aggs; + int naggs = state->dts_naggregations << 1; + int onaggs = state->dts_naggregations; + + ASSERT(aggid == state->dts_naggregations + 1); + + if (naggs == 0) { + ASSERT(oaggs == NULL); + naggs = 1; + } + + aggs = kmem_zalloc(naggs * sizeof (*aggs), KM_SLEEP); + + if (oaggs != NULL) { + bcopy(oaggs, aggs, onaggs * sizeof (*aggs)); + kmem_free(oaggs, onaggs * sizeof (*aggs)); + } + + state->dts_aggregations = aggs; + state->dts_naggregations = naggs; + } + + ASSERT(state->dts_aggregations[aggid - 1] == NULL); + state->dts_aggregations[(agg->dtag_id = aggid) - 1] = agg; + + frec = &agg->dtag_first->dta_rec; + if (frec->dtrd_alignment < sizeof (dtrace_aggid_t)) + frec->dtrd_alignment = sizeof (dtrace_aggid_t); + + for (act = agg->dtag_first; act != NULL; act = act->dta_next) { + ASSERT(!act->dta_intuple); + act->dta_intuple = 1; + } + + return (&agg->dtag_action); +} + +static void +dtrace_ecb_aggregation_destroy(dtrace_ecb_t *ecb, dtrace_action_t *act) +{ + dtrace_aggregation_t *agg = (dtrace_aggregation_t *)act; + dtrace_state_t *state = ecb->dte_state; + dtrace_aggid_t aggid = agg->dtag_id; + + ASSERT(DTRACEACT_ISAGG(act->dta_kind)); +#ifdef illumos + vmem_free(state->dts_aggid_arena, (void *)(uintptr_t)aggid, 1); +#else + free_unr(state->dts_aggid_arena, aggid); +#endif + + ASSERT(state->dts_aggregations[aggid - 1] == agg); + state->dts_aggregations[aggid - 1] = NULL; + + kmem_free(agg, sizeof (dtrace_aggregation_t)); +} + +static int +dtrace_ecb_action_add(dtrace_ecb_t *ecb, dtrace_actdesc_t *desc) +{ + dtrace_action_t *action, *last; + dtrace_difo_t *dp = desc->dtad_difo; + uint32_t size = 0, align = sizeof (uint8_t), mask; + uint16_t format = 0; + dtrace_recdesc_t *rec; + dtrace_state_t *state = ecb->dte_state; + dtrace_optval_t *opt = state->dts_options, nframes = 0, strsize; + uint64_t arg = desc->dtad_arg; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(ecb->dte_action == NULL || ecb->dte_action->dta_refcnt == 1); + + if (DTRACEACT_ISAGG(desc->dtad_kind)) { + /* + * If this is an aggregating action, there must be neither + * a speculate nor a commit on the action chain. + */ + dtrace_action_t *act; + + for (act = ecb->dte_action; act != NULL; act = act->dta_next) { + if (act->dta_kind == DTRACEACT_COMMIT) + return (EINVAL); + + if (act->dta_kind == DTRACEACT_SPECULATE) + return (EINVAL); + } + + action = dtrace_ecb_aggregation_create(ecb, desc); + + if (action == NULL) + return (EINVAL); + } else { + if (DTRACEACT_ISDESTRUCTIVE(desc->dtad_kind) || + (desc->dtad_kind == DTRACEACT_DIFEXPR && + dp != NULL && dp->dtdo_destructive)) { + state->dts_destructive = 1; + } + + switch (desc->dtad_kind) { + case DTRACEACT_PRINTF: + case DTRACEACT_PRINTA: + case DTRACEACT_SYSTEM: + case DTRACEACT_FREOPEN: + case DTRACEACT_DIFEXPR: + /* + * We know that our arg is a string -- turn it into a + * format. + */ + if (arg == 0) { + ASSERT(desc->dtad_kind == DTRACEACT_PRINTA || + desc->dtad_kind == DTRACEACT_DIFEXPR); + format = 0; + } else { + ASSERT(arg != 0); +#ifdef illumos + ASSERT(arg > KERNELBASE); +#endif + format = dtrace_format_add(state, + (char *)(uintptr_t)arg); + } + + /*FALLTHROUGH*/ + case DTRACEACT_LIBACT: + case DTRACEACT_TRACEMEM: + case DTRACEACT_TRACEMEM_DYNSIZE: + if (dp == NULL) + return (EINVAL); + + if ((size = dp->dtdo_rtype.dtdt_size) != 0) + break; + + if (dp->dtdo_rtype.dtdt_kind == DIF_TYPE_STRING) { + if (!(dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF)) + return (EINVAL); + + size = opt[DTRACEOPT_STRSIZE]; + } + + break; + + case DTRACEACT_STACK: + if ((nframes = arg) == 0) { + nframes = opt[DTRACEOPT_STACKFRAMES]; + ASSERT(nframes > 0); + arg = nframes; + } + + size = nframes * sizeof (pc_t); + break; + + case DTRACEACT_JSTACK: + if ((strsize = DTRACE_USTACK_STRSIZE(arg)) == 0) + strsize = opt[DTRACEOPT_JSTACKSTRSIZE]; + + if ((nframes = DTRACE_USTACK_NFRAMES(arg)) == 0) + nframes = opt[DTRACEOPT_JSTACKFRAMES]; + + arg = DTRACE_USTACK_ARG(nframes, strsize); + + /*FALLTHROUGH*/ + case DTRACEACT_USTACK: + if (desc->dtad_kind != DTRACEACT_JSTACK && + (nframes = DTRACE_USTACK_NFRAMES(arg)) == 0) { + strsize = DTRACE_USTACK_STRSIZE(arg); + nframes = opt[DTRACEOPT_USTACKFRAMES]; + ASSERT(nframes > 0); + arg = DTRACE_USTACK_ARG(nframes, strsize); + } + + /* + * Save a slot for the pid. + */ + size = (nframes + 1) * sizeof (uint64_t); + size += DTRACE_USTACK_STRSIZE(arg); + size = P2ROUNDUP(size, (uint32_t)(sizeof (uintptr_t))); + + break; + + case DTRACEACT_SYM: + case DTRACEACT_MOD: + if (dp == NULL || ((size = dp->dtdo_rtype.dtdt_size) != + sizeof (uint64_t)) || + (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF)) + return (EINVAL); + break; + + case DTRACEACT_USYM: + case DTRACEACT_UMOD: + case DTRACEACT_UADDR: + if (dp == NULL || + (dp->dtdo_rtype.dtdt_size != sizeof (uint64_t)) || + (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF)) + return (EINVAL); + + /* + * We have a slot for the pid, plus a slot for the + * argument. To keep things simple (aligned with + * bitness-neutral sizing), we store each as a 64-bit + * quantity. + */ + size = 2 * sizeof (uint64_t); + break; + + case DTRACEACT_STOP: + case DTRACEACT_BREAKPOINT: + case DTRACEACT_PANIC: + break; + + case DTRACEACT_CHILL: + case DTRACEACT_DISCARD: + case DTRACEACT_RAISE: + if (dp == NULL) + return (EINVAL); + break; + + case DTRACEACT_EXIT: + if (dp == NULL || + (size = dp->dtdo_rtype.dtdt_size) != sizeof (int) || + (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF)) + return (EINVAL); + break; + + case DTRACEACT_SPECULATE: + if (ecb->dte_size > sizeof (dtrace_rechdr_t)) + return (EINVAL); + + if (dp == NULL) + return (EINVAL); + + state->dts_speculates = 1; + break; + + case DTRACEACT_PRINTM: + size = dp->dtdo_rtype.dtdt_size; + break; + + case DTRACEACT_COMMIT: { + dtrace_action_t *act = ecb->dte_action; + + for (; act != NULL; act = act->dta_next) { + if (act->dta_kind == DTRACEACT_COMMIT) + return (EINVAL); + } + + if (dp == NULL) + return (EINVAL); + break; + } + + default: + return (EINVAL); + } + + if (size != 0 || desc->dtad_kind == DTRACEACT_SPECULATE) { + /* + * If this is a data-storing action or a speculate, + * we must be sure that there isn't a commit on the + * action chain. + */ + dtrace_action_t *act = ecb->dte_action; + + for (; act != NULL; act = act->dta_next) { + if (act->dta_kind == DTRACEACT_COMMIT) + return (EINVAL); + } + } + + action = kmem_zalloc(sizeof (dtrace_action_t), KM_SLEEP); + action->dta_rec.dtrd_size = size; + } + + action->dta_refcnt = 1; + rec = &action->dta_rec; + size = rec->dtrd_size; + + for (mask = sizeof (uint64_t) - 1; size != 0 && mask > 0; mask >>= 1) { + if (!(size & mask)) { + align = mask + 1; + break; + } + } + + action->dta_kind = desc->dtad_kind; + + if ((action->dta_difo = dp) != NULL) + dtrace_difo_hold(dp); + + rec->dtrd_action = action->dta_kind; + rec->dtrd_arg = arg; + rec->dtrd_uarg = desc->dtad_uarg; + rec->dtrd_alignment = (uint16_t)align; + rec->dtrd_format = format; + + if ((last = ecb->dte_action_last) != NULL) { + ASSERT(ecb->dte_action != NULL); + action->dta_prev = last; + last->dta_next = action; + } else { + ASSERT(ecb->dte_action == NULL); + ecb->dte_action = action; + } + + ecb->dte_action_last = action; + + return (0); +} + +static void +dtrace_ecb_action_remove(dtrace_ecb_t *ecb) +{ + dtrace_action_t *act = ecb->dte_action, *next; + dtrace_vstate_t *vstate = &ecb->dte_state->dts_vstate; + dtrace_difo_t *dp; + uint16_t format; + + if (act != NULL && act->dta_refcnt > 1) { + ASSERT(act->dta_next == NULL || act->dta_next->dta_refcnt == 1); + act->dta_refcnt--; + } else { + for (; act != NULL; act = next) { + next = act->dta_next; + ASSERT(next != NULL || act == ecb->dte_action_last); + ASSERT(act->dta_refcnt == 1); + + if ((format = act->dta_rec.dtrd_format) != 0) + dtrace_format_remove(ecb->dte_state, format); + + if ((dp = act->dta_difo) != NULL) + dtrace_difo_release(dp, vstate); + + if (DTRACEACT_ISAGG(act->dta_kind)) { + dtrace_ecb_aggregation_destroy(ecb, act); + } else { + kmem_free(act, sizeof (dtrace_action_t)); + } + } + } + + ecb->dte_action = NULL; + ecb->dte_action_last = NULL; + ecb->dte_size = 0; +} + +static void +dtrace_ecb_disable(dtrace_ecb_t *ecb) +{ + /* + * We disable the ECB by removing it from its probe. + */ + dtrace_ecb_t *pecb, *prev = NULL; + dtrace_probe_t *probe = ecb->dte_probe; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + + if (probe == NULL) { + /* + * This is the NULL probe; there is nothing to disable. + */ + return; + } + + for (pecb = probe->dtpr_ecb; pecb != NULL; pecb = pecb->dte_next) { + if (pecb == ecb) + break; + prev = pecb; + } + + ASSERT(pecb != NULL); + + if (prev == NULL) { + probe->dtpr_ecb = ecb->dte_next; + } else { + prev->dte_next = ecb->dte_next; + } + + if (ecb == probe->dtpr_ecb_last) { + ASSERT(ecb->dte_next == NULL); + probe->dtpr_ecb_last = prev; + } + + /* + * The ECB has been disconnected from the probe; now sync to assure + * that all CPUs have seen the change before returning. + */ + dtrace_sync(); + + if (probe->dtpr_ecb == NULL) { + /* + * That was the last ECB on the probe; clear the predicate + * cache ID for the probe, disable it and sync one more time + * to assure that we'll never hit it again. + */ + dtrace_provider_t *prov = probe->dtpr_provider; + + ASSERT(ecb->dte_next == NULL); + ASSERT(probe->dtpr_ecb_last == NULL); + probe->dtpr_predcache = DTRACE_CACHEIDNONE; + prov->dtpv_pops.dtps_disable(prov->dtpv_arg, + probe->dtpr_id, probe->dtpr_arg); + dtrace_sync(); + } else { + /* + * There is at least one ECB remaining on the probe. If there + * is _exactly_ one, set the probe's predicate cache ID to be + * the predicate cache ID of the remaining ECB. + */ + ASSERT(probe->dtpr_ecb_last != NULL); + ASSERT(probe->dtpr_predcache == DTRACE_CACHEIDNONE); + + if (probe->dtpr_ecb == probe->dtpr_ecb_last) { + dtrace_predicate_t *p = probe->dtpr_ecb->dte_predicate; + + ASSERT(probe->dtpr_ecb->dte_next == NULL); + + if (p != NULL) + probe->dtpr_predcache = p->dtp_cacheid; + } + + ecb->dte_next = NULL; + } +} + +static void +dtrace_ecb_destroy(dtrace_ecb_t *ecb) +{ + dtrace_state_t *state = ecb->dte_state; + dtrace_vstate_t *vstate = &state->dts_vstate; + dtrace_predicate_t *pred; + dtrace_epid_t epid = ecb->dte_epid; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(ecb->dte_next == NULL); + ASSERT(ecb->dte_probe == NULL || ecb->dte_probe->dtpr_ecb != ecb); + + if ((pred = ecb->dte_predicate) != NULL) + dtrace_predicate_release(pred, vstate); + + dtrace_ecb_action_remove(ecb); + + ASSERT(state->dts_ecbs[epid - 1] == ecb); + state->dts_ecbs[epid - 1] = NULL; + + kmem_free(ecb, sizeof (dtrace_ecb_t)); +} + +static dtrace_ecb_t * +dtrace_ecb_create(dtrace_state_t *state, dtrace_probe_t *probe, + dtrace_enabling_t *enab) +{ + dtrace_ecb_t *ecb; + dtrace_predicate_t *pred; + dtrace_actdesc_t *act; + dtrace_provider_t *prov; + dtrace_ecbdesc_t *desc = enab->dten_current; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(state != NULL); + + ecb = dtrace_ecb_add(state, probe); + ecb->dte_uarg = desc->dted_uarg; + + if ((pred = desc->dted_pred.dtpdd_predicate) != NULL) { + dtrace_predicate_hold(pred); + ecb->dte_predicate = pred; + } + + if (probe != NULL) { + /* + * If the provider shows more leg than the consumer is old + * enough to see, we need to enable the appropriate implicit + * predicate bits to prevent the ecb from activating at + * revealing times. + * + * Providers specifying DTRACE_PRIV_USER at register time + * are stating that they need the /proc-style privilege + * model to be enforced, and this is what DTRACE_COND_OWNER + * and DTRACE_COND_ZONEOWNER will then do at probe time. + */ + prov = probe->dtpr_provider; + if (!(state->dts_cred.dcr_visible & DTRACE_CRV_ALLPROC) && + (prov->dtpv_priv.dtpp_flags & DTRACE_PRIV_USER)) + ecb->dte_cond |= DTRACE_COND_OWNER; + + if (!(state->dts_cred.dcr_visible & DTRACE_CRV_ALLZONE) && + (prov->dtpv_priv.dtpp_flags & DTRACE_PRIV_USER)) + ecb->dte_cond |= DTRACE_COND_ZONEOWNER; + + /* + * If the provider shows us kernel innards and the user + * is lacking sufficient privilege, enable the + * DTRACE_COND_USERMODE implicit predicate. + */ + if (!(state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL) && + (prov->dtpv_priv.dtpp_flags & DTRACE_PRIV_KERNEL)) + ecb->dte_cond |= DTRACE_COND_USERMODE; + } + + if (dtrace_ecb_create_cache != NULL) { + /* + * If we have a cached ecb, we'll use its action list instead + * of creating our own (saving both time and space). + */ + dtrace_ecb_t *cached = dtrace_ecb_create_cache; + dtrace_action_t *act = cached->dte_action; + + if (act != NULL) { + ASSERT(act->dta_refcnt > 0); + act->dta_refcnt++; + ecb->dte_action = act; + ecb->dte_action_last = cached->dte_action_last; + ecb->dte_needed = cached->dte_needed; + ecb->dte_size = cached->dte_size; + ecb->dte_alignment = cached->dte_alignment; + } + + return (ecb); + } + + for (act = desc->dted_action; act != NULL; act = act->dtad_next) { + if ((enab->dten_error = dtrace_ecb_action_add(ecb, act)) != 0) { + dtrace_ecb_destroy(ecb); + return (NULL); + } + } + + if ((enab->dten_error = dtrace_ecb_resize(ecb)) != 0) { + dtrace_ecb_destroy(ecb); + return (NULL); + } + + return (dtrace_ecb_create_cache = ecb); +} + +static int +dtrace_ecb_create_enable(dtrace_probe_t *probe, void *arg) +{ + dtrace_ecb_t *ecb; + dtrace_enabling_t *enab = arg; + dtrace_state_t *state = enab->dten_vstate->dtvs_state; + + ASSERT(state != NULL); + + if (probe != NULL && probe->dtpr_gen < enab->dten_probegen) { + /* + * This probe was created in a generation for which this + * enabling has previously created ECBs; we don't want to + * enable it again, so just kick out. + */ + return (DTRACE_MATCH_NEXT); + } + + if ((ecb = dtrace_ecb_create(state, probe, enab)) == NULL) + return (DTRACE_MATCH_DONE); + + dtrace_ecb_enable(ecb); + return (DTRACE_MATCH_NEXT); +} + +static dtrace_ecb_t * +dtrace_epid2ecb(dtrace_state_t *state, dtrace_epid_t id) +{ + dtrace_ecb_t *ecb; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + + if (id == 0 || id > state->dts_necbs) + return (NULL); + + ASSERT(state->dts_necbs > 0 && state->dts_ecbs != NULL); + ASSERT((ecb = state->dts_ecbs[id - 1]) == NULL || ecb->dte_epid == id); + + return (state->dts_ecbs[id - 1]); +} + +static dtrace_aggregation_t * +dtrace_aggid2agg(dtrace_state_t *state, dtrace_aggid_t id) +{ + dtrace_aggregation_t *agg; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + + if (id == 0 || id > state->dts_naggregations) + return (NULL); + + ASSERT(state->dts_naggregations > 0 && state->dts_aggregations != NULL); + ASSERT((agg = state->dts_aggregations[id - 1]) == NULL || + agg->dtag_id == id); + + return (state->dts_aggregations[id - 1]); +} + +/* + * DTrace Buffer Functions + * + * The following functions manipulate DTrace buffers. Most of these functions + * are called in the context of establishing or processing consumer state; + * exceptions are explicitly noted. + */ + +/* + * Note: called from cross call context. This function switches the two + * buffers on a given CPU. The atomicity of this operation is assured by + * disabling interrupts while the actual switch takes place; the disabling of + * interrupts serializes the execution with any execution of dtrace_probe() on + * the same CPU. + */ +static void +dtrace_buffer_switch(dtrace_buffer_t *buf) +{ + caddr_t tomax = buf->dtb_tomax; + caddr_t xamot = buf->dtb_xamot; + dtrace_icookie_t cookie; + hrtime_t now; + + ASSERT(!(buf->dtb_flags & DTRACEBUF_NOSWITCH)); + ASSERT(!(buf->dtb_flags & DTRACEBUF_RING)); + + cookie = dtrace_interrupt_disable(); + now = dtrace_gethrtime(); + buf->dtb_tomax = xamot; + buf->dtb_xamot = tomax; + buf->dtb_xamot_drops = buf->dtb_drops; + buf->dtb_xamot_offset = buf->dtb_offset; + buf->dtb_xamot_errors = buf->dtb_errors; + buf->dtb_xamot_flags = buf->dtb_flags; + buf->dtb_offset = 0; + buf->dtb_drops = 0; + buf->dtb_errors = 0; + buf->dtb_flags &= ~(DTRACEBUF_ERROR | DTRACEBUF_DROPPED); + buf->dtb_interval = now - buf->dtb_switched; + buf->dtb_switched = now; + dtrace_interrupt_enable(cookie); +} + +/* + * Note: called from cross call context. This function activates a buffer + * on a CPU. As with dtrace_buffer_switch(), the atomicity of the operation + * is guaranteed by the disabling of interrupts. + */ +static void +dtrace_buffer_activate(dtrace_state_t *state) +{ + dtrace_buffer_t *buf; + dtrace_icookie_t cookie = dtrace_interrupt_disable(); + + buf = &state->dts_buffer[curcpu]; + + if (buf->dtb_tomax != NULL) { + /* + * We might like to assert that the buffer is marked inactive, + * but this isn't necessarily true: the buffer for the CPU + * that processes the BEGIN probe has its buffer activated + * manually. In this case, we take the (harmless) action + * re-clearing the bit INACTIVE bit. + */ + buf->dtb_flags &= ~DTRACEBUF_INACTIVE; + } + + dtrace_interrupt_enable(cookie); +} + +#ifdef __FreeBSD__ +/* + * Activate the specified per-CPU buffer. This is used instead of + * dtrace_buffer_activate() when APs have not yet started, i.e. when + * activating anonymous state. + */ +static void +dtrace_buffer_activate_cpu(dtrace_state_t *state, int cpu) +{ + + if (state->dts_buffer[cpu].dtb_tomax != NULL) + state->dts_buffer[cpu].dtb_flags &= ~DTRACEBUF_INACTIVE; +} +#endif + +static int +dtrace_buffer_alloc(dtrace_buffer_t *bufs, size_t size, int flags, + processorid_t cpu, int *factor) +{ +#ifdef illumos + cpu_t *cp; +#endif + dtrace_buffer_t *buf; + int allocated = 0, desired = 0; + +#ifdef illumos + ASSERT(MUTEX_HELD(&cpu_lock)); + ASSERT(MUTEX_HELD(&dtrace_lock)); + + *factor = 1; + + if (size > dtrace_nonroot_maxsize && + !PRIV_POLICY_CHOICE(CRED(), PRIV_ALL, B_FALSE)) + return (EFBIG); + + cp = cpu_list; + + do { + if (cpu != DTRACE_CPUALL && cpu != cp->cpu_id) + continue; + + buf = &bufs[cp->cpu_id]; + + /* + * If there is already a buffer allocated for this CPU, it + * is only possible that this is a DR event. In this case, + */ + if (buf->dtb_tomax != NULL) { + ASSERT(buf->dtb_size == size); + continue; + } + + ASSERT(buf->dtb_xamot == NULL); + + if ((buf->dtb_tomax = kmem_zalloc(size, + KM_NOSLEEP | KM_NORMALPRI)) == NULL) + goto err; + + buf->dtb_size = size; + buf->dtb_flags = flags; + buf->dtb_offset = 0; + buf->dtb_drops = 0; + + if (flags & DTRACEBUF_NOSWITCH) + continue; + + if ((buf->dtb_xamot = kmem_zalloc(size, + KM_NOSLEEP | KM_NORMALPRI)) == NULL) + goto err; + } while ((cp = cp->cpu_next) != cpu_list); + + return (0); + +err: + cp = cpu_list; + + do { + if (cpu != DTRACE_CPUALL && cpu != cp->cpu_id) + continue; + + buf = &bufs[cp->cpu_id]; + desired += 2; + + if (buf->dtb_xamot != NULL) { + ASSERT(buf->dtb_tomax != NULL); + ASSERT(buf->dtb_size == size); + kmem_free(buf->dtb_xamot, size); + allocated++; + } + + if (buf->dtb_tomax != NULL) { + ASSERT(buf->dtb_size == size); + kmem_free(buf->dtb_tomax, size); + allocated++; + } + + buf->dtb_tomax = NULL; + buf->dtb_xamot = NULL; + buf->dtb_size = 0; + } while ((cp = cp->cpu_next) != cpu_list); +#else + int i; + + *factor = 1; +#if defined(__aarch64__) || defined(__amd64__) || defined(__arm__) || \ + defined(__mips__) || defined(__powerpc__) || defined(__riscv) + /* + * FreeBSD isn't good at limiting the amount of memory we + * ask to malloc, so let's place a limit here before trying + * to do something that might well end in tears at bedtime. + */ + if (size > physmem * PAGE_SIZE / (128 * (mp_maxid + 1))) + return (ENOMEM); +#endif + + ASSERT(MUTEX_HELD(&dtrace_lock)); + CPU_FOREACH(i) { + if (cpu != DTRACE_CPUALL && cpu != i) + continue; + + buf = &bufs[i]; + + /* + * If there is already a buffer allocated for this CPU, it + * is only possible that this is a DR event. In this case, + * the buffer size must match our specified size. + */ + if (buf->dtb_tomax != NULL) { + ASSERT(buf->dtb_size == size); + continue; + } + + ASSERT(buf->dtb_xamot == NULL); + + if ((buf->dtb_tomax = kmem_zalloc(size, + KM_NOSLEEP | KM_NORMALPRI)) == NULL) + goto err; + + buf->dtb_size = size; + buf->dtb_flags = flags; + buf->dtb_offset = 0; + buf->dtb_drops = 0; + + if (flags & DTRACEBUF_NOSWITCH) + continue; + + if ((buf->dtb_xamot = kmem_zalloc(size, + KM_NOSLEEP | KM_NORMALPRI)) == NULL) + goto err; + } + + return (0); + +err: + /* + * Error allocating memory, so free the buffers that were + * allocated before the failed allocation. + */ + CPU_FOREACH(i) { + if (cpu != DTRACE_CPUALL && cpu != i) + continue; + + buf = &bufs[i]; + desired += 2; + + if (buf->dtb_xamot != NULL) { + ASSERT(buf->dtb_tomax != NULL); + ASSERT(buf->dtb_size == size); + kmem_free(buf->dtb_xamot, size); + allocated++; + } + + if (buf->dtb_tomax != NULL) { + ASSERT(buf->dtb_size == size); + kmem_free(buf->dtb_tomax, size); + allocated++; + } + + buf->dtb_tomax = NULL; + buf->dtb_xamot = NULL; + buf->dtb_size = 0; + + } +#endif + *factor = desired / (allocated > 0 ? allocated : 1); + + return (ENOMEM); +} + +/* + * Note: called from probe context. This function just increments the drop + * count on a buffer. It has been made a function to allow for the + * possibility of understanding the source of mysterious drop counts. (A + * problem for which one may be particularly disappointed that DTrace cannot + * be used to understand DTrace.) + */ +static void +dtrace_buffer_drop(dtrace_buffer_t *buf) +{ + buf->dtb_drops++; +} + +/* + * Note: called from probe context. This function is called to reserve space + * in a buffer. If mstate is non-NULL, sets the scratch base and size in the + * mstate. Returns the new offset in the buffer, or a negative value if an + * error has occurred. + */ +static intptr_t +dtrace_buffer_reserve(dtrace_buffer_t *buf, size_t needed, size_t align, + dtrace_state_t *state, dtrace_mstate_t *mstate) +{ + intptr_t offs = buf->dtb_offset, soffs; + intptr_t woffs; + caddr_t tomax; + size_t total; + + if (buf->dtb_flags & DTRACEBUF_INACTIVE) + return (-1); + + if ((tomax = buf->dtb_tomax) == NULL) { + dtrace_buffer_drop(buf); + return (-1); + } + + if (!(buf->dtb_flags & (DTRACEBUF_RING | DTRACEBUF_FILL))) { + while (offs & (align - 1)) { + /* + * Assert that our alignment is off by a number which + * is itself sizeof (uint32_t) aligned. + */ + ASSERT(!((align - (offs & (align - 1))) & + (sizeof (uint32_t) - 1))); + DTRACE_STORE(uint32_t, tomax, offs, DTRACE_EPIDNONE); + offs += sizeof (uint32_t); + } + + if ((soffs = offs + needed) > buf->dtb_size) { + dtrace_buffer_drop(buf); + return (-1); + } + + if (mstate == NULL) + return (offs); + + mstate->dtms_scratch_base = (uintptr_t)tomax + soffs; + mstate->dtms_scratch_size = buf->dtb_size - soffs; + mstate->dtms_scratch_ptr = mstate->dtms_scratch_base; + + return (offs); + } + + if (buf->dtb_flags & DTRACEBUF_FILL) { + if (state->dts_activity != DTRACE_ACTIVITY_COOLDOWN && + (buf->dtb_flags & DTRACEBUF_FULL)) + return (-1); + goto out; + } + + total = needed + (offs & (align - 1)); + + /* + * For a ring buffer, life is quite a bit more complicated. Before + * we can store any padding, we need to adjust our wrapping offset. + * (If we've never before wrapped or we're not about to, no adjustment + * is required.) + */ + if ((buf->dtb_flags & DTRACEBUF_WRAPPED) || + offs + total > buf->dtb_size) { + woffs = buf->dtb_xamot_offset; + + if (offs + total > buf->dtb_size) { + /* + * We can't fit in the end of the buffer. First, a + * sanity check that we can fit in the buffer at all. + */ + if (total > buf->dtb_size) { + dtrace_buffer_drop(buf); + return (-1); + } + + /* + * We're going to be storing at the top of the buffer, + * so now we need to deal with the wrapped offset. We + * only reset our wrapped offset to 0 if it is + * currently greater than the current offset. If it + * is less than the current offset, it is because a + * previous allocation induced a wrap -- but the + * allocation didn't subsequently take the space due + * to an error or false predicate evaluation. In this + * case, we'll just leave the wrapped offset alone: if + * the wrapped offset hasn't been advanced far enough + * for this allocation, it will be adjusted in the + * lower loop. + */ + if (buf->dtb_flags & DTRACEBUF_WRAPPED) { + if (woffs >= offs) + woffs = 0; + } else { + woffs = 0; + } + + /* + * Now we know that we're going to be storing to the + * top of the buffer and that there is room for us + * there. We need to clear the buffer from the current + * offset to the end (there may be old gunk there). + */ + while (offs < buf->dtb_size) + tomax[offs++] = 0; + + /* + * We need to set our offset to zero. And because we + * are wrapping, we need to set the bit indicating as + * much. We can also adjust our needed space back + * down to the space required by the ECB -- we know + * that the top of the buffer is aligned. + */ + offs = 0; + total = needed; + buf->dtb_flags |= DTRACEBUF_WRAPPED; + } else { + /* + * There is room for us in the buffer, so we simply + * need to check the wrapped offset. + */ + if (woffs < offs) { + /* + * The wrapped offset is less than the offset. + * This can happen if we allocated buffer space + * that induced a wrap, but then we didn't + * subsequently take the space due to an error + * or false predicate evaluation. This is + * okay; we know that _this_ allocation isn't + * going to induce a wrap. We still can't + * reset the wrapped offset to be zero, + * however: the space may have been trashed in + * the previous failed probe attempt. But at + * least the wrapped offset doesn't need to + * be adjusted at all... + */ + goto out; + } + } + + while (offs + total > woffs) { + dtrace_epid_t epid = *(uint32_t *)(tomax + woffs); + size_t size; + + if (epid == DTRACE_EPIDNONE) { + size = sizeof (uint32_t); + } else { + ASSERT3U(epid, <=, state->dts_necbs); + ASSERT(state->dts_ecbs[epid - 1] != NULL); + + size = state->dts_ecbs[epid - 1]->dte_size; + } + + ASSERT(woffs + size <= buf->dtb_size); + ASSERT(size != 0); + + if (woffs + size == buf->dtb_size) { + /* + * We've reached the end of the buffer; we want + * to set the wrapped offset to 0 and break + * out. However, if the offs is 0, then we're + * in a strange edge-condition: the amount of + * space that we want to reserve plus the size + * of the record that we're overwriting is + * greater than the size of the buffer. This + * is problematic because if we reserve the + * space but subsequently don't consume it (due + * to a failed predicate or error) the wrapped + * offset will be 0 -- yet the EPID at offset 0 + * will not be committed. This situation is + * relatively easy to deal with: if we're in + * this case, the buffer is indistinguishable + * from one that hasn't wrapped; we need only + * finish the job by clearing the wrapped bit, + * explicitly setting the offset to be 0, and + * zero'ing out the old data in the buffer. + */ + if (offs == 0) { + buf->dtb_flags &= ~DTRACEBUF_WRAPPED; + buf->dtb_offset = 0; + woffs = total; + + while (woffs < buf->dtb_size) + tomax[woffs++] = 0; + } + + woffs = 0; + break; + } + + woffs += size; + } + + /* + * We have a wrapped offset. It may be that the wrapped offset + * has become zero -- that's okay. + */ + buf->dtb_xamot_offset = woffs; + } + +out: + /* + * Now we can plow the buffer with any necessary padding. + */ + while (offs & (align - 1)) { + /* + * Assert that our alignment is off by a number which + * is itself sizeof (uint32_t) aligned. + */ + ASSERT(!((align - (offs & (align - 1))) & + (sizeof (uint32_t) - 1))); + DTRACE_STORE(uint32_t, tomax, offs, DTRACE_EPIDNONE); + offs += sizeof (uint32_t); + } + + if (buf->dtb_flags & DTRACEBUF_FILL) { + if (offs + needed > buf->dtb_size - state->dts_reserve) { + buf->dtb_flags |= DTRACEBUF_FULL; + return (-1); + } + } + + if (mstate == NULL) + return (offs); + + /* + * For ring buffers and fill buffers, the scratch space is always + * the inactive buffer. + */ + mstate->dtms_scratch_base = (uintptr_t)buf->dtb_xamot; + mstate->dtms_scratch_size = buf->dtb_size; + mstate->dtms_scratch_ptr = mstate->dtms_scratch_base; + + return (offs); +} + +static void +dtrace_buffer_polish(dtrace_buffer_t *buf) +{ + ASSERT(buf->dtb_flags & DTRACEBUF_RING); + ASSERT(MUTEX_HELD(&dtrace_lock)); + + if (!(buf->dtb_flags & DTRACEBUF_WRAPPED)) + return; + + /* + * We need to polish the ring buffer. There are three cases: + * + * - The first (and presumably most common) is that there is no gap + * between the buffer offset and the wrapped offset. In this case, + * there is nothing in the buffer that isn't valid data; we can + * mark the buffer as polished and return. + * + * - The second (less common than the first but still more common + * than the third) is that there is a gap between the buffer offset + * and the wrapped offset, and the wrapped offset is larger than the + * buffer offset. This can happen because of an alignment issue, or + * can happen because of a call to dtrace_buffer_reserve() that + * didn't subsequently consume the buffer space. In this case, + * we need to zero the data from the buffer offset to the wrapped + * offset. + * + * - The third (and least common) is that there is a gap between the + * buffer offset and the wrapped offset, but the wrapped offset is + * _less_ than the buffer offset. This can only happen because a + * call to dtrace_buffer_reserve() induced a wrap, but the space + * was not subsequently consumed. In this case, we need to zero the + * space from the offset to the end of the buffer _and_ from the + * top of the buffer to the wrapped offset. + */ + if (buf->dtb_offset < buf->dtb_xamot_offset) { + bzero(buf->dtb_tomax + buf->dtb_offset, + buf->dtb_xamot_offset - buf->dtb_offset); + } + + if (buf->dtb_offset > buf->dtb_xamot_offset) { + bzero(buf->dtb_tomax + buf->dtb_offset, + buf->dtb_size - buf->dtb_offset); + bzero(buf->dtb_tomax, buf->dtb_xamot_offset); + } +} + +/* + * This routine determines if data generated at the specified time has likely + * been entirely consumed at user-level. This routine is called to determine + * if an ECB on a defunct probe (but for an active enabling) can be safely + * disabled and destroyed. + */ +static int +dtrace_buffer_consumed(dtrace_buffer_t *bufs, hrtime_t when) +{ + int i; + + for (i = 0; i < NCPU; i++) { + dtrace_buffer_t *buf = &bufs[i]; + + if (buf->dtb_size == 0) + continue; + + if (buf->dtb_flags & DTRACEBUF_RING) + return (0); + + if (!buf->dtb_switched && buf->dtb_offset != 0) + return (0); + + if (buf->dtb_switched - buf->dtb_interval < when) + return (0); + } + + return (1); +} + +static void +dtrace_buffer_free(dtrace_buffer_t *bufs) +{ + int i; + + for (i = 0; i < NCPU; i++) { + dtrace_buffer_t *buf = &bufs[i]; + + if (buf->dtb_tomax == NULL) { + ASSERT(buf->dtb_xamot == NULL); + ASSERT(buf->dtb_size == 0); + continue; + } + + if (buf->dtb_xamot != NULL) { + ASSERT(!(buf->dtb_flags & DTRACEBUF_NOSWITCH)); + kmem_free(buf->dtb_xamot, buf->dtb_size); + } + + kmem_free(buf->dtb_tomax, buf->dtb_size); + buf->dtb_size = 0; + buf->dtb_tomax = NULL; + buf->dtb_xamot = NULL; + } +} + +/* + * DTrace Enabling Functions + */ +static dtrace_enabling_t * +dtrace_enabling_create(dtrace_vstate_t *vstate) +{ + dtrace_enabling_t *enab; + + enab = kmem_zalloc(sizeof (dtrace_enabling_t), KM_SLEEP); + enab->dten_vstate = vstate; + + return (enab); +} + +static void +dtrace_enabling_add(dtrace_enabling_t *enab, dtrace_ecbdesc_t *ecb) +{ + dtrace_ecbdesc_t **ndesc; + size_t osize, nsize; + + /* + * We can't add to enablings after we've enabled them, or after we've + * retained them. + */ + ASSERT(enab->dten_probegen == 0); + ASSERT(enab->dten_next == NULL && enab->dten_prev == NULL); + + if (enab->dten_ndesc < enab->dten_maxdesc) { + enab->dten_desc[enab->dten_ndesc++] = ecb; + return; + } + + osize = enab->dten_maxdesc * sizeof (dtrace_enabling_t *); + + if (enab->dten_maxdesc == 0) { + enab->dten_maxdesc = 1; + } else { + enab->dten_maxdesc <<= 1; + } + + ASSERT(enab->dten_ndesc < enab->dten_maxdesc); + + nsize = enab->dten_maxdesc * sizeof (dtrace_enabling_t *); + ndesc = kmem_zalloc(nsize, KM_SLEEP); + bcopy(enab->dten_desc, ndesc, osize); + if (enab->dten_desc != NULL) + kmem_free(enab->dten_desc, osize); + + enab->dten_desc = ndesc; + enab->dten_desc[enab->dten_ndesc++] = ecb; +} + +static void +dtrace_enabling_addlike(dtrace_enabling_t *enab, dtrace_ecbdesc_t *ecb, + dtrace_probedesc_t *pd) +{ + dtrace_ecbdesc_t *new; + dtrace_predicate_t *pred; + dtrace_actdesc_t *act; + + /* + * We're going to create a new ECB description that matches the + * specified ECB in every way, but has the specified probe description. + */ + new = kmem_zalloc(sizeof (dtrace_ecbdesc_t), KM_SLEEP); + + if ((pred = ecb->dted_pred.dtpdd_predicate) != NULL) + dtrace_predicate_hold(pred); + + for (act = ecb->dted_action; act != NULL; act = act->dtad_next) + dtrace_actdesc_hold(act); + + new->dted_action = ecb->dted_action; + new->dted_pred = ecb->dted_pred; + new->dted_probe = *pd; + new->dted_uarg = ecb->dted_uarg; + + dtrace_enabling_add(enab, new); +} + +static void +dtrace_enabling_dump(dtrace_enabling_t *enab) +{ + int i; + + for (i = 0; i < enab->dten_ndesc; i++) { + dtrace_probedesc_t *desc = &enab->dten_desc[i]->dted_probe; + +#ifdef __FreeBSD__ + printf("dtrace: enabling probe %d (%s:%s:%s:%s)\n", i, + desc->dtpd_provider, desc->dtpd_mod, + desc->dtpd_func, desc->dtpd_name); +#else + cmn_err(CE_NOTE, "enabling probe %d (%s:%s:%s:%s)", i, + desc->dtpd_provider, desc->dtpd_mod, + desc->dtpd_func, desc->dtpd_name); +#endif + } +} + +static void +dtrace_enabling_destroy(dtrace_enabling_t *enab) +{ + int i; + dtrace_ecbdesc_t *ep; + dtrace_vstate_t *vstate = enab->dten_vstate; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + + for (i = 0; i < enab->dten_ndesc; i++) { + dtrace_actdesc_t *act, *next; + dtrace_predicate_t *pred; + + ep = enab->dten_desc[i]; + + if ((pred = ep->dted_pred.dtpdd_predicate) != NULL) + dtrace_predicate_release(pred, vstate); + + for (act = ep->dted_action; act != NULL; act = next) { + next = act->dtad_next; + dtrace_actdesc_release(act, vstate); + } + + kmem_free(ep, sizeof (dtrace_ecbdesc_t)); + } + + if (enab->dten_desc != NULL) + kmem_free(enab->dten_desc, + enab->dten_maxdesc * sizeof (dtrace_enabling_t *)); + + /* + * If this was a retained enabling, decrement the dts_nretained count + * and take it off of the dtrace_retained list. + */ + if (enab->dten_prev != NULL || enab->dten_next != NULL || + dtrace_retained == enab) { + ASSERT(enab->dten_vstate->dtvs_state != NULL); + ASSERT(enab->dten_vstate->dtvs_state->dts_nretained > 0); + enab->dten_vstate->dtvs_state->dts_nretained--; + dtrace_retained_gen++; + } + + if (enab->dten_prev == NULL) { + if (dtrace_retained == enab) { + dtrace_retained = enab->dten_next; + + if (dtrace_retained != NULL) + dtrace_retained->dten_prev = NULL; + } + } else { + ASSERT(enab != dtrace_retained); + ASSERT(dtrace_retained != NULL); + enab->dten_prev->dten_next = enab->dten_next; + } + + if (enab->dten_next != NULL) { + ASSERT(dtrace_retained != NULL); + enab->dten_next->dten_prev = enab->dten_prev; + } + + kmem_free(enab, sizeof (dtrace_enabling_t)); +} + +static int +dtrace_enabling_retain(dtrace_enabling_t *enab) +{ + dtrace_state_t *state; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(enab->dten_next == NULL && enab->dten_prev == NULL); + ASSERT(enab->dten_vstate != NULL); + + state = enab->dten_vstate->dtvs_state; + ASSERT(state != NULL); + + /* + * We only allow each state to retain dtrace_retain_max enablings. + */ + if (state->dts_nretained >= dtrace_retain_max) + return (ENOSPC); + + state->dts_nretained++; + dtrace_retained_gen++; + + if (dtrace_retained == NULL) { + dtrace_retained = enab; + return (0); + } + + enab->dten_next = dtrace_retained; + dtrace_retained->dten_prev = enab; + dtrace_retained = enab; + + return (0); +} + +static int +dtrace_enabling_replicate(dtrace_state_t *state, dtrace_probedesc_t *match, + dtrace_probedesc_t *create) +{ + dtrace_enabling_t *new, *enab; + int found = 0, err = ENOENT; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(strlen(match->dtpd_provider) < DTRACE_PROVNAMELEN); + ASSERT(strlen(match->dtpd_mod) < DTRACE_MODNAMELEN); + ASSERT(strlen(match->dtpd_func) < DTRACE_FUNCNAMELEN); + ASSERT(strlen(match->dtpd_name) < DTRACE_NAMELEN); + + new = dtrace_enabling_create(&state->dts_vstate); + + /* + * Iterate over all retained enablings, looking for enablings that + * match the specified state. + */ + for (enab = dtrace_retained; enab != NULL; enab = enab->dten_next) { + int i; + + /* + * dtvs_state can only be NULL for helper enablings -- and + * helper enablings can't be retained. + */ + ASSERT(enab->dten_vstate->dtvs_state != NULL); + + if (enab->dten_vstate->dtvs_state != state) + continue; + + /* + * Now iterate over each probe description; we're looking for + * an exact match to the specified probe description. + */ + for (i = 0; i < enab->dten_ndesc; i++) { + dtrace_ecbdesc_t *ep = enab->dten_desc[i]; + dtrace_probedesc_t *pd = &ep->dted_probe; + + if (strcmp(pd->dtpd_provider, match->dtpd_provider)) + continue; + + if (strcmp(pd->dtpd_mod, match->dtpd_mod)) + continue; + + if (strcmp(pd->dtpd_func, match->dtpd_func)) + continue; + + if (strcmp(pd->dtpd_name, match->dtpd_name)) + continue; + + /* + * We have a winning probe! Add it to our growing + * enabling. + */ + found = 1; + dtrace_enabling_addlike(new, ep, create); + } + } + + if (!found || (err = dtrace_enabling_retain(new)) != 0) { + dtrace_enabling_destroy(new); + return (err); + } + + return (0); +} + +static void +dtrace_enabling_retract(dtrace_state_t *state) +{ + dtrace_enabling_t *enab, *next; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + + /* + * Iterate over all retained enablings, destroy the enablings retained + * for the specified state. + */ + for (enab = dtrace_retained; enab != NULL; enab = next) { + next = enab->dten_next; + + /* + * dtvs_state can only be NULL for helper enablings -- and + * helper enablings can't be retained. + */ + ASSERT(enab->dten_vstate->dtvs_state != NULL); + + if (enab->dten_vstate->dtvs_state == state) { + ASSERT(state->dts_nretained > 0); + dtrace_enabling_destroy(enab); + } + } + + ASSERT(state->dts_nretained == 0); +} + +static int +dtrace_enabling_match(dtrace_enabling_t *enab, int *nmatched) +{ + int i = 0; + int matched = 0; + + ASSERT(MUTEX_HELD(&cpu_lock)); + ASSERT(MUTEX_HELD(&dtrace_lock)); + + for (i = 0; i < enab->dten_ndesc; i++) { + dtrace_ecbdesc_t *ep = enab->dten_desc[i]; + + enab->dten_current = ep; + enab->dten_error = 0; + + matched += dtrace_probe_enable(&ep->dted_probe, enab); + + if (enab->dten_error != 0) { + /* + * If we get an error half-way through enabling the + * probes, we kick out -- perhaps with some number of + * them enabled. Leaving enabled probes enabled may + * be slightly confusing for user-level, but we expect + * that no one will attempt to actually drive on in + * the face of such errors. If this is an anonymous + * enabling (indicated with a NULL nmatched pointer), + * we cmn_err() a message. We aren't expecting to + * get such an error -- such as it can exist at all, + * it would be a result of corrupted DOF in the driver + * properties. + */ + if (nmatched == NULL) { + cmn_err(CE_WARN, "dtrace_enabling_match() " + "error on %p: %d", (void *)ep, + enab->dten_error); + } + + return (enab->dten_error); + } + } + + enab->dten_probegen = dtrace_probegen; + if (nmatched != NULL) + *nmatched = matched; + + return (0); +} + +static void +dtrace_enabling_matchall(void) +{ + dtrace_enabling_t *enab; + + mutex_enter(&cpu_lock); + mutex_enter(&dtrace_lock); + + /* + * Iterate over all retained enablings to see if any probes match + * against them. We only perform this operation on enablings for which + * we have sufficient permissions by virtue of being in the global zone + * or in the same zone as the DTrace client. Because we can be called + * after dtrace_detach() has been called, we cannot assert that there + * are retained enablings. We can safely load from dtrace_retained, + * however: the taskq_destroy() at the end of dtrace_detach() will + * block pending our completion. + */ + for (enab = dtrace_retained; enab != NULL; enab = enab->dten_next) { +#ifdef illumos + cred_t *cr = enab->dten_vstate->dtvs_state->dts_cred.dcr_cred; + + if (INGLOBALZONE(curproc) || + cr != NULL && getzoneid() == crgetzoneid(cr)) +#endif + (void) dtrace_enabling_match(enab, NULL); + } + + mutex_exit(&dtrace_lock); + mutex_exit(&cpu_lock); +} + +/* + * If an enabling is to be enabled without having matched probes (that is, if + * dtrace_state_go() is to be called on the underlying dtrace_state_t), the + * enabling must be _primed_ by creating an ECB for every ECB description. + * This must be done to assure that we know the number of speculations, the + * number of aggregations, the minimum buffer size needed, etc. before we + * transition out of DTRACE_ACTIVITY_INACTIVE. To do this without actually + * enabling any probes, we create ECBs for every ECB decription, but with a + * NULL probe -- which is exactly what this function does. + */ +static void +dtrace_enabling_prime(dtrace_state_t *state) +{ + dtrace_enabling_t *enab; + int i; + + for (enab = dtrace_retained; enab != NULL; enab = enab->dten_next) { + ASSERT(enab->dten_vstate->dtvs_state != NULL); + + if (enab->dten_vstate->dtvs_state != state) + continue; + + /* + * We don't want to prime an enabling more than once, lest + * we allow a malicious user to induce resource exhaustion. + * (The ECBs that result from priming an enabling aren't + * leaked -- but they also aren't deallocated until the + * consumer state is destroyed.) + */ + if (enab->dten_primed) + continue; + + for (i = 0; i < enab->dten_ndesc; i++) { + enab->dten_current = enab->dten_desc[i]; + (void) dtrace_probe_enable(NULL, enab); + } + + enab->dten_primed = 1; + } +} + +/* + * Called to indicate that probes should be provided due to retained + * enablings. This is implemented in terms of dtrace_probe_provide(), but it + * must take an initial lap through the enabling calling the dtps_provide() + * entry point explicitly to allow for autocreated probes. + */ +static void +dtrace_enabling_provide(dtrace_provider_t *prv) +{ + int i, all = 0; + dtrace_probedesc_t desc; + dtrace_genid_t gen; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(MUTEX_HELD(&dtrace_provider_lock)); + + if (prv == NULL) { + all = 1; + prv = dtrace_provider; + } + + do { + dtrace_enabling_t *enab; + void *parg = prv->dtpv_arg; + +retry: + gen = dtrace_retained_gen; + for (enab = dtrace_retained; enab != NULL; + enab = enab->dten_next) { + for (i = 0; i < enab->dten_ndesc; i++) { + desc = enab->dten_desc[i]->dted_probe; + mutex_exit(&dtrace_lock); + prv->dtpv_pops.dtps_provide(parg, &desc); + mutex_enter(&dtrace_lock); + /* + * Process the retained enablings again if + * they have changed while we weren't holding + * dtrace_lock. + */ + if (gen != dtrace_retained_gen) + goto retry; + } + } + } while (all && (prv = prv->dtpv_next) != NULL); + + mutex_exit(&dtrace_lock); + dtrace_probe_provide(NULL, all ? NULL : prv); + mutex_enter(&dtrace_lock); +} + +/* + * Called to reap ECBs that are attached to probes from defunct providers. + */ +static void +dtrace_enabling_reap(void) +{ + dtrace_provider_t *prov; + dtrace_probe_t *probe; + dtrace_ecb_t *ecb; + hrtime_t when; + int i; + + mutex_enter(&cpu_lock); + mutex_enter(&dtrace_lock); + + for (i = 0; i < dtrace_nprobes; i++) { + if ((probe = dtrace_probes[i]) == NULL) + continue; + + if (probe->dtpr_ecb == NULL) + continue; + + prov = probe->dtpr_provider; + + if ((when = prov->dtpv_defunct) == 0) + continue; + + /* + * We have ECBs on a defunct provider: we want to reap these + * ECBs to allow the provider to unregister. The destruction + * of these ECBs must be done carefully: if we destroy the ECB + * and the consumer later wishes to consume an EPID that + * corresponds to the destroyed ECB (and if the EPID metadata + * has not been previously consumed), the consumer will abort + * processing on the unknown EPID. To reduce (but not, sadly, + * eliminate) the possibility of this, we will only destroy an + * ECB for a defunct provider if, for the state that + * corresponds to the ECB: + * + * (a) There is no speculative tracing (which can effectively + * cache an EPID for an arbitrary amount of time). + * + * (b) The principal buffers have been switched twice since the + * provider became defunct. + * + * (c) The aggregation buffers are of zero size or have been + * switched twice since the provider became defunct. + * + * We use dts_speculates to determine (a) and call a function + * (dtrace_buffer_consumed()) to determine (b) and (c). Note + * that as soon as we've been unable to destroy one of the ECBs + * associated with the probe, we quit trying -- reaping is only + * fruitful in as much as we can destroy all ECBs associated + * with the defunct provider's probes. + */ + while ((ecb = probe->dtpr_ecb) != NULL) { + dtrace_state_t *state = ecb->dte_state; + dtrace_buffer_t *buf = state->dts_buffer; + dtrace_buffer_t *aggbuf = state->dts_aggbuffer; + + if (state->dts_speculates) + break; + + if (!dtrace_buffer_consumed(buf, when)) + break; + + if (!dtrace_buffer_consumed(aggbuf, when)) + break; + + dtrace_ecb_disable(ecb); + ASSERT(probe->dtpr_ecb != ecb); + dtrace_ecb_destroy(ecb); + } + } + + mutex_exit(&dtrace_lock); + mutex_exit(&cpu_lock); +} + +/* + * DTrace DOF Functions + */ +/*ARGSUSED*/ +static void +dtrace_dof_error(dof_hdr_t *dof, const char *str) +{ + if (dtrace_err_verbose) + cmn_err(CE_WARN, "failed to process DOF: %s", str); + +#ifdef DTRACE_ERRDEBUG + dtrace_errdebug(str); +#endif +} + +/* + * Create DOF out of a currently enabled state. Right now, we only create + * DOF containing the run-time options -- but this could be expanded to create + * complete DOF representing the enabled state. + */ +static dof_hdr_t * +dtrace_dof_create(dtrace_state_t *state) +{ + dof_hdr_t *dof; + dof_sec_t *sec; + dof_optdesc_t *opt; + int i, len = sizeof (dof_hdr_t) + + roundup(sizeof (dof_sec_t), sizeof (uint64_t)) + + sizeof (dof_optdesc_t) * DTRACEOPT_MAX; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + + dof = kmem_zalloc(len, KM_SLEEP); + dof->dofh_ident[DOF_ID_MAG0] = DOF_MAG_MAG0; + dof->dofh_ident[DOF_ID_MAG1] = DOF_MAG_MAG1; + dof->dofh_ident[DOF_ID_MAG2] = DOF_MAG_MAG2; + dof->dofh_ident[DOF_ID_MAG3] = DOF_MAG_MAG3; + + dof->dofh_ident[DOF_ID_MODEL] = DOF_MODEL_NATIVE; + dof->dofh_ident[DOF_ID_ENCODING] = DOF_ENCODE_NATIVE; + dof->dofh_ident[DOF_ID_VERSION] = DOF_VERSION; + dof->dofh_ident[DOF_ID_DIFVERS] = DIF_VERSION; + dof->dofh_ident[DOF_ID_DIFIREG] = DIF_DIR_NREGS; + dof->dofh_ident[DOF_ID_DIFTREG] = DIF_DTR_NREGS; + + dof->dofh_flags = 0; + dof->dofh_hdrsize = sizeof (dof_hdr_t); + dof->dofh_secsize = sizeof (dof_sec_t); + dof->dofh_secnum = 1; /* only DOF_SECT_OPTDESC */ + dof->dofh_secoff = sizeof (dof_hdr_t); + dof->dofh_loadsz = len; + dof->dofh_filesz = len; + dof->dofh_pad = 0; + + /* + * Fill in the option section header... + */ + sec = (dof_sec_t *)((uintptr_t)dof + sizeof (dof_hdr_t)); + sec->dofs_type = DOF_SECT_OPTDESC; + sec->dofs_align = sizeof (uint64_t); + sec->dofs_flags = DOF_SECF_LOAD; + sec->dofs_entsize = sizeof (dof_optdesc_t); + + opt = (dof_optdesc_t *)((uintptr_t)sec + + roundup(sizeof (dof_sec_t), sizeof (uint64_t))); + + sec->dofs_offset = (uintptr_t)opt - (uintptr_t)dof; + sec->dofs_size = sizeof (dof_optdesc_t) * DTRACEOPT_MAX; + + for (i = 0; i < DTRACEOPT_MAX; i++) { + opt[i].dofo_option = i; + opt[i].dofo_strtab = DOF_SECIDX_NONE; + opt[i].dofo_value = state->dts_options[i]; + } + + return (dof); +} + +static dof_hdr_t * +dtrace_dof_copyin(uintptr_t uarg, int *errp) +{ + dof_hdr_t hdr, *dof; + + ASSERT(!MUTEX_HELD(&dtrace_lock)); + + /* + * First, we're going to copyin() the sizeof (dof_hdr_t). + */ + if (copyin((void *)uarg, &hdr, sizeof (hdr)) != 0) { + dtrace_dof_error(NULL, "failed to copyin DOF header"); + *errp = EFAULT; + return (NULL); + } + + /* + * Now we'll allocate the entire DOF and copy it in -- provided + * that the length isn't outrageous. + */ + if (hdr.dofh_loadsz >= dtrace_dof_maxsize) { + dtrace_dof_error(&hdr, "load size exceeds maximum"); + *errp = E2BIG; + return (NULL); + } + + if (hdr.dofh_loadsz < sizeof (hdr)) { + dtrace_dof_error(&hdr, "invalid load size"); + *errp = EINVAL; + return (NULL); + } + + dof = kmem_alloc(hdr.dofh_loadsz, KM_SLEEP); + + if (copyin((void *)uarg, dof, hdr.dofh_loadsz) != 0 || + dof->dofh_loadsz != hdr.dofh_loadsz) { + kmem_free(dof, hdr.dofh_loadsz); + *errp = EFAULT; + return (NULL); + } + + return (dof); +} + +#ifdef __FreeBSD__ +static dof_hdr_t * +dtrace_dof_copyin_proc(struct proc *p, uintptr_t uarg, int *errp) +{ + dof_hdr_t hdr, *dof; + struct thread *td; + size_t loadsz; + + ASSERT(!MUTEX_HELD(&dtrace_lock)); + + td = curthread; + + /* + * First, we're going to copyin() the sizeof (dof_hdr_t). + */ + if (proc_readmem(td, p, uarg, &hdr, sizeof(hdr)) != sizeof(hdr)) { + dtrace_dof_error(NULL, "failed to copyin DOF header"); + *errp = EFAULT; + return (NULL); + } + + /* + * Now we'll allocate the entire DOF and copy it in -- provided + * that the length isn't outrageous. + */ + if (hdr.dofh_loadsz >= dtrace_dof_maxsize) { + dtrace_dof_error(&hdr, "load size exceeds maximum"); + *errp = E2BIG; + return (NULL); + } + loadsz = (size_t)hdr.dofh_loadsz; + + if (loadsz < sizeof (hdr)) { + dtrace_dof_error(&hdr, "invalid load size"); + *errp = EINVAL; + return (NULL); + } + + dof = kmem_alloc(loadsz, KM_SLEEP); + + if (proc_readmem(td, p, uarg, dof, loadsz) != loadsz || + dof->dofh_loadsz != loadsz) { + kmem_free(dof, hdr.dofh_loadsz); + *errp = EFAULT; + return (NULL); + } + + return (dof); +} + +static __inline uchar_t +dtrace_dof_char(char c) +{ + + switch (c) { + case '0': + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + return (c - '0'); + case 'A': + case 'B': + case 'C': + case 'D': + case 'E': + case 'F': + return (c - 'A' + 10); + case 'a': + case 'b': + case 'c': + case 'd': + case 'e': + case 'f': + return (c - 'a' + 10); + } + /* Should not reach here. */ + return (UCHAR_MAX); +} +#endif /* __FreeBSD__ */ + +static dof_hdr_t * +dtrace_dof_property(const char *name) +{ +#ifdef __FreeBSD__ + uint8_t *dofbuf; + u_char *data, *eol; + caddr_t doffile; + size_t bytes, len, i; + dof_hdr_t *dof; + u_char c1, c2; + + dof = NULL; + + doffile = preload_search_by_type("dtrace_dof"); + if (doffile == NULL) + return (NULL); + + data = preload_fetch_addr(doffile); + len = preload_fetch_size(doffile); + for (;;) { + /* Look for the end of the line. All lines end in a newline. */ + eol = memchr(data, '\n', len); + if (eol == NULL) + return (NULL); + + if (strncmp(name, data, strlen(name)) == 0) + break; + + eol++; /* skip past the newline */ + len -= eol - data; + data = eol; + } + + /* We've found the data corresponding to the specified key. */ + + data += strlen(name) + 1; /* skip past the '=' */ + len = eol - data; + if (len % 2 != 0) { + dtrace_dof_error(NULL, "invalid DOF encoding length"); + goto doferr; + } + bytes = len / 2; + if (bytes < sizeof(dof_hdr_t)) { + dtrace_dof_error(NULL, "truncated header"); + goto doferr; + } + + /* + * Each byte is represented by the two ASCII characters in its hex + * representation. + */ + dofbuf = malloc(bytes, M_SOLARIS, M_WAITOK); + for (i = 0; i < bytes; i++) { + c1 = dtrace_dof_char(data[i * 2]); + c2 = dtrace_dof_char(data[i * 2 + 1]); + if (c1 == UCHAR_MAX || c2 == UCHAR_MAX) { + dtrace_dof_error(NULL, "invalid hex char in DOF"); + goto doferr; + } + dofbuf[i] = c1 * 16 + c2; + } + + dof = (dof_hdr_t *)dofbuf; + if (bytes < dof->dofh_loadsz) { + dtrace_dof_error(NULL, "truncated DOF"); + goto doferr; + } + + if (dof->dofh_loadsz >= dtrace_dof_maxsize) { + dtrace_dof_error(NULL, "oversized DOF"); + goto doferr; + } + + return (dof); + +doferr: + free(dof, M_SOLARIS); + return (NULL); +#else /* __FreeBSD__ */ + uchar_t *buf; + uint64_t loadsz; + unsigned int len, i; + dof_hdr_t *dof; + + /* + * Unfortunately, array of values in .conf files are always (and + * only) interpreted to be integer arrays. We must read our DOF + * as an integer array, and then squeeze it into a byte array. + */ + if (ddi_prop_lookup_int_array(DDI_DEV_T_ANY, dtrace_devi, 0, + (char *)name, (int **)&buf, &len) != DDI_PROP_SUCCESS) + return (NULL); + + for (i = 0; i < len; i++) + buf[i] = (uchar_t)(((int *)buf)[i]); + + if (len < sizeof (dof_hdr_t)) { + ddi_prop_free(buf); + dtrace_dof_error(NULL, "truncated header"); + return (NULL); + } + + if (len < (loadsz = ((dof_hdr_t *)buf)->dofh_loadsz)) { + ddi_prop_free(buf); + dtrace_dof_error(NULL, "truncated DOF"); + return (NULL); + } + + if (loadsz >= dtrace_dof_maxsize) { + ddi_prop_free(buf); + dtrace_dof_error(NULL, "oversized DOF"); + return (NULL); + } + + dof = kmem_alloc(loadsz, KM_SLEEP); + bcopy(buf, dof, loadsz); + ddi_prop_free(buf); + + return (dof); +#endif /* !__FreeBSD__ */ +} + +static void +dtrace_dof_destroy(dof_hdr_t *dof) +{ + kmem_free(dof, dof->dofh_loadsz); +} + +/* + * Return the dof_sec_t pointer corresponding to a given section index. If the + * index is not valid, dtrace_dof_error() is called and NULL is returned. If + * a type other than DOF_SECT_NONE is specified, the header is checked against + * this type and NULL is returned if the types do not match. + */ +static dof_sec_t * +dtrace_dof_sect(dof_hdr_t *dof, uint32_t type, dof_secidx_t i) +{ + dof_sec_t *sec = (dof_sec_t *)(uintptr_t) + ((uintptr_t)dof + dof->dofh_secoff + i * dof->dofh_secsize); + + if (i >= dof->dofh_secnum) { + dtrace_dof_error(dof, "referenced section index is invalid"); + return (NULL); + } + + if (!(sec->dofs_flags & DOF_SECF_LOAD)) { + dtrace_dof_error(dof, "referenced section is not loadable"); + return (NULL); + } + + if (type != DOF_SECT_NONE && type != sec->dofs_type) { + dtrace_dof_error(dof, "referenced section is the wrong type"); + return (NULL); + } + + return (sec); +} + +static dtrace_probedesc_t * +dtrace_dof_probedesc(dof_hdr_t *dof, dof_sec_t *sec, dtrace_probedesc_t *desc) +{ + dof_probedesc_t *probe; + dof_sec_t *strtab; + uintptr_t daddr = (uintptr_t)dof; + uintptr_t str; + size_t size; + + if (sec->dofs_type != DOF_SECT_PROBEDESC) { + dtrace_dof_error(dof, "invalid probe section"); + return (NULL); + } + + if (sec->dofs_align != sizeof (dof_secidx_t)) { + dtrace_dof_error(dof, "bad alignment in probe description"); + return (NULL); + } + + if (sec->dofs_offset + sizeof (dof_probedesc_t) > dof->dofh_loadsz) { + dtrace_dof_error(dof, "truncated probe description"); + return (NULL); + } + + probe = (dof_probedesc_t *)(uintptr_t)(daddr + sec->dofs_offset); + strtab = dtrace_dof_sect(dof, DOF_SECT_STRTAB, probe->dofp_strtab); + + if (strtab == NULL) + return (NULL); + + str = daddr + strtab->dofs_offset; + size = strtab->dofs_size; + + if (probe->dofp_provider >= strtab->dofs_size) { + dtrace_dof_error(dof, "corrupt probe provider"); + return (NULL); + } + + (void) strncpy(desc->dtpd_provider, + (char *)(str + probe->dofp_provider), + MIN(DTRACE_PROVNAMELEN - 1, size - probe->dofp_provider)); + + if (probe->dofp_mod >= strtab->dofs_size) { + dtrace_dof_error(dof, "corrupt probe module"); + return (NULL); + } + + (void) strncpy(desc->dtpd_mod, (char *)(str + probe->dofp_mod), + MIN(DTRACE_MODNAMELEN - 1, size - probe->dofp_mod)); + + if (probe->dofp_func >= strtab->dofs_size) { + dtrace_dof_error(dof, "corrupt probe function"); + return (NULL); + } + + (void) strncpy(desc->dtpd_func, (char *)(str + probe->dofp_func), + MIN(DTRACE_FUNCNAMELEN - 1, size - probe->dofp_func)); + + if (probe->dofp_name >= strtab->dofs_size) { + dtrace_dof_error(dof, "corrupt probe name"); + return (NULL); + } + + (void) strncpy(desc->dtpd_name, (char *)(str + probe->dofp_name), + MIN(DTRACE_NAMELEN - 1, size - probe->dofp_name)); + + return (desc); +} + +static dtrace_difo_t * +dtrace_dof_difo(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate, + cred_t *cr) +{ + dtrace_difo_t *dp; + size_t ttl = 0; + dof_difohdr_t *dofd; + uintptr_t daddr = (uintptr_t)dof; + size_t max = dtrace_difo_maxsize; + int i, l, n; + + static const struct { + int section; + int bufoffs; + int lenoffs; + int entsize; + int align; + const char *msg; + } difo[] = { + { DOF_SECT_DIF, offsetof(dtrace_difo_t, dtdo_buf), + offsetof(dtrace_difo_t, dtdo_len), sizeof (dif_instr_t), + sizeof (dif_instr_t), "multiple DIF sections" }, + + { DOF_SECT_INTTAB, offsetof(dtrace_difo_t, dtdo_inttab), + offsetof(dtrace_difo_t, dtdo_intlen), sizeof (uint64_t), + sizeof (uint64_t), "multiple integer tables" }, + + { DOF_SECT_STRTAB, offsetof(dtrace_difo_t, dtdo_strtab), + offsetof(dtrace_difo_t, dtdo_strlen), 0, + sizeof (char), "multiple string tables" }, + + { DOF_SECT_VARTAB, offsetof(dtrace_difo_t, dtdo_vartab), + offsetof(dtrace_difo_t, dtdo_varlen), sizeof (dtrace_difv_t), + sizeof (uint_t), "multiple variable tables" }, + + { DOF_SECT_NONE, 0, 0, 0, 0, NULL } + }; + + if (sec->dofs_type != DOF_SECT_DIFOHDR) { + dtrace_dof_error(dof, "invalid DIFO header section"); + return (NULL); + } + + if (sec->dofs_align != sizeof (dof_secidx_t)) { + dtrace_dof_error(dof, "bad alignment in DIFO header"); + return (NULL); + } + + if (sec->dofs_size < sizeof (dof_difohdr_t) || + sec->dofs_size % sizeof (dof_secidx_t)) { + dtrace_dof_error(dof, "bad size in DIFO header"); + return (NULL); + } + + dofd = (dof_difohdr_t *)(uintptr_t)(daddr + sec->dofs_offset); + n = (sec->dofs_size - sizeof (*dofd)) / sizeof (dof_secidx_t) + 1; + + dp = kmem_zalloc(sizeof (dtrace_difo_t), KM_SLEEP); + dp->dtdo_rtype = dofd->dofd_rtype; + + for (l = 0; l < n; l++) { + dof_sec_t *subsec; + void **bufp; + uint32_t *lenp; + + if ((subsec = dtrace_dof_sect(dof, DOF_SECT_NONE, + dofd->dofd_links[l])) == NULL) + goto err; /* invalid section link */ + + if (ttl + subsec->dofs_size > max) { + dtrace_dof_error(dof, "exceeds maximum size"); + goto err; + } + + ttl += subsec->dofs_size; + + for (i = 0; difo[i].section != DOF_SECT_NONE; i++) { + if (subsec->dofs_type != difo[i].section) + continue; + + if (!(subsec->dofs_flags & DOF_SECF_LOAD)) { + dtrace_dof_error(dof, "section not loaded"); + goto err; + } + + if (subsec->dofs_align != difo[i].align) { + dtrace_dof_error(dof, "bad alignment"); + goto err; + } + + bufp = (void **)((uintptr_t)dp + difo[i].bufoffs); + lenp = (uint32_t *)((uintptr_t)dp + difo[i].lenoffs); + + if (*bufp != NULL) { + dtrace_dof_error(dof, difo[i].msg); + goto err; + } + + if (difo[i].entsize != subsec->dofs_entsize) { + dtrace_dof_error(dof, "entry size mismatch"); + goto err; + } + + if (subsec->dofs_entsize != 0 && + (subsec->dofs_size % subsec->dofs_entsize) != 0) { + dtrace_dof_error(dof, "corrupt entry size"); + goto err; + } + + *lenp = subsec->dofs_size; + *bufp = kmem_alloc(subsec->dofs_size, KM_SLEEP); + bcopy((char *)(uintptr_t)(daddr + subsec->dofs_offset), + *bufp, subsec->dofs_size); + + if (subsec->dofs_entsize != 0) + *lenp /= subsec->dofs_entsize; + + break; + } + + /* + * If we encounter a loadable DIFO sub-section that is not + * known to us, assume this is a broken program and fail. + */ + if (difo[i].section == DOF_SECT_NONE && + (subsec->dofs_flags & DOF_SECF_LOAD)) { + dtrace_dof_error(dof, "unrecognized DIFO subsection"); + goto err; + } + } + + if (dp->dtdo_buf == NULL) { + /* + * We can't have a DIF object without DIF text. + */ + dtrace_dof_error(dof, "missing DIF text"); + goto err; + } + + /* + * Before we validate the DIF object, run through the variable table + * looking for the strings -- if any of their size are under, we'll set + * their size to be the system-wide default string size. Note that + * this should _not_ happen if the "strsize" option has been set -- + * in this case, the compiler should have set the size to reflect the + * setting of the option. + */ + for (i = 0; i < dp->dtdo_varlen; i++) { + dtrace_difv_t *v = &dp->dtdo_vartab[i]; + dtrace_diftype_t *t = &v->dtdv_type; + + if (v->dtdv_id < DIF_VAR_OTHER_UBASE) + continue; + + if (t->dtdt_kind == DIF_TYPE_STRING && t->dtdt_size == 0) + t->dtdt_size = dtrace_strsize_default; + } + + if (dtrace_difo_validate(dp, vstate, DIF_DIR_NREGS, cr) != 0) + goto err; + + dtrace_difo_init(dp, vstate); + return (dp); + +err: + kmem_free(dp->dtdo_buf, dp->dtdo_len * sizeof (dif_instr_t)); + kmem_free(dp->dtdo_inttab, dp->dtdo_intlen * sizeof (uint64_t)); + kmem_free(dp->dtdo_strtab, dp->dtdo_strlen); + kmem_free(dp->dtdo_vartab, dp->dtdo_varlen * sizeof (dtrace_difv_t)); + + kmem_free(dp, sizeof (dtrace_difo_t)); + return (NULL); +} + +static dtrace_predicate_t * +dtrace_dof_predicate(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate, + cred_t *cr) +{ + dtrace_difo_t *dp; + + if ((dp = dtrace_dof_difo(dof, sec, vstate, cr)) == NULL) + return (NULL); + + return (dtrace_predicate_create(dp)); +} + +static dtrace_actdesc_t * +dtrace_dof_actdesc(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate, + cred_t *cr) +{ + dtrace_actdesc_t *act, *first = NULL, *last = NULL, *next; + dof_actdesc_t *desc; + dof_sec_t *difosec; + size_t offs; + uintptr_t daddr = (uintptr_t)dof; + uint64_t arg; + dtrace_actkind_t kind; + + if (sec->dofs_type != DOF_SECT_ACTDESC) { + dtrace_dof_error(dof, "invalid action section"); + return (NULL); + } + + if (sec->dofs_offset + sizeof (dof_actdesc_t) > dof->dofh_loadsz) { + dtrace_dof_error(dof, "truncated action description"); + return (NULL); + } + + if (sec->dofs_align != sizeof (uint64_t)) { + dtrace_dof_error(dof, "bad alignment in action description"); + return (NULL); + } + + if (sec->dofs_size < sec->dofs_entsize) { + dtrace_dof_error(dof, "section entry size exceeds total size"); + return (NULL); + } + + if (sec->dofs_entsize != sizeof (dof_actdesc_t)) { + dtrace_dof_error(dof, "bad entry size in action description"); + return (NULL); + } + + if (sec->dofs_size / sec->dofs_entsize > dtrace_actions_max) { + dtrace_dof_error(dof, "actions exceed dtrace_actions_max"); + return (NULL); + } + + for (offs = 0; offs < sec->dofs_size; offs += sec->dofs_entsize) { + desc = (dof_actdesc_t *)(daddr + + (uintptr_t)sec->dofs_offset + offs); + kind = (dtrace_actkind_t)desc->dofa_kind; + + if ((DTRACEACT_ISPRINTFLIKE(kind) && + (kind != DTRACEACT_PRINTA || + desc->dofa_strtab != DOF_SECIDX_NONE)) || + (kind == DTRACEACT_DIFEXPR && + desc->dofa_strtab != DOF_SECIDX_NONE)) { + dof_sec_t *strtab; + char *str, *fmt; + uint64_t i; + + /* + * The argument to these actions is an index into the + * DOF string table. For printf()-like actions, this + * is the format string. For print(), this is the + * CTF type of the expression result. + */ + if ((strtab = dtrace_dof_sect(dof, + DOF_SECT_STRTAB, desc->dofa_strtab)) == NULL) + goto err; + + str = (char *)((uintptr_t)dof + + (uintptr_t)strtab->dofs_offset); + + for (i = desc->dofa_arg; i < strtab->dofs_size; i++) { + if (str[i] == '\0') + break; + } + + if (i >= strtab->dofs_size) { + dtrace_dof_error(dof, "bogus format string"); + goto err; + } + + if (i == desc->dofa_arg) { + dtrace_dof_error(dof, "empty format string"); + goto err; + } + + i -= desc->dofa_arg; + fmt = kmem_alloc(i + 1, KM_SLEEP); + bcopy(&str[desc->dofa_arg], fmt, i + 1); + arg = (uint64_t)(uintptr_t)fmt; + } else { + if (kind == DTRACEACT_PRINTA) { + ASSERT(desc->dofa_strtab == DOF_SECIDX_NONE); + arg = 0; + } else { + arg = desc->dofa_arg; + } + } + + act = dtrace_actdesc_create(kind, desc->dofa_ntuple, + desc->dofa_uarg, arg); + + if (last != NULL) { + last->dtad_next = act; + } else { + first = act; + } + + last = act; + + if (desc->dofa_difo == DOF_SECIDX_NONE) + continue; + + if ((difosec = dtrace_dof_sect(dof, + DOF_SECT_DIFOHDR, desc->dofa_difo)) == NULL) + goto err; + + act->dtad_difo = dtrace_dof_difo(dof, difosec, vstate, cr); + + if (act->dtad_difo == NULL) + goto err; + } + + ASSERT(first != NULL); + return (first); + +err: + for (act = first; act != NULL; act = next) { + next = act->dtad_next; + dtrace_actdesc_release(act, vstate); + } + + return (NULL); +} + +static dtrace_ecbdesc_t * +dtrace_dof_ecbdesc(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate, + cred_t *cr) +{ + dtrace_ecbdesc_t *ep; + dof_ecbdesc_t *ecb; + dtrace_probedesc_t *desc; + dtrace_predicate_t *pred = NULL; + + if (sec->dofs_size < sizeof (dof_ecbdesc_t)) { + dtrace_dof_error(dof, "truncated ECB description"); + return (NULL); + } + + if (sec->dofs_align != sizeof (uint64_t)) { + dtrace_dof_error(dof, "bad alignment in ECB description"); + return (NULL); + } + + ecb = (dof_ecbdesc_t *)((uintptr_t)dof + (uintptr_t)sec->dofs_offset); + sec = dtrace_dof_sect(dof, DOF_SECT_PROBEDESC, ecb->dofe_probes); + + if (sec == NULL) + return (NULL); + + ep = kmem_zalloc(sizeof (dtrace_ecbdesc_t), KM_SLEEP); + ep->dted_uarg = ecb->dofe_uarg; + desc = &ep->dted_probe; + + if (dtrace_dof_probedesc(dof, sec, desc) == NULL) + goto err; + + if (ecb->dofe_pred != DOF_SECIDX_NONE) { + if ((sec = dtrace_dof_sect(dof, + DOF_SECT_DIFOHDR, ecb->dofe_pred)) == NULL) + goto err; + + if ((pred = dtrace_dof_predicate(dof, sec, vstate, cr)) == NULL) + goto err; + + ep->dted_pred.dtpdd_predicate = pred; + } + + if (ecb->dofe_actions != DOF_SECIDX_NONE) { + if ((sec = dtrace_dof_sect(dof, + DOF_SECT_ACTDESC, ecb->dofe_actions)) == NULL) + goto err; + + ep->dted_action = dtrace_dof_actdesc(dof, sec, vstate, cr); + + if (ep->dted_action == NULL) + goto err; + } + + return (ep); + +err: + if (pred != NULL) + dtrace_predicate_release(pred, vstate); + kmem_free(ep, sizeof (dtrace_ecbdesc_t)); + return (NULL); +} + +/* + * Apply the relocations from the specified 'sec' (a DOF_SECT_URELHDR) to the + * specified DOF. SETX relocations are computed using 'ubase', the base load + * address of the object containing the DOF, and DOFREL relocations are relative + * to the relocation offset within the DOF. + */ +static int +dtrace_dof_relocate(dof_hdr_t *dof, dof_sec_t *sec, uint64_t ubase, + uint64_t udaddr) +{ + uintptr_t daddr = (uintptr_t)dof; + uintptr_t ts_end; + dof_relohdr_t *dofr = + (dof_relohdr_t *)(uintptr_t)(daddr + sec->dofs_offset); + dof_sec_t *ss, *rs, *ts; + dof_relodesc_t *r; + uint_t i, n; + + if (sec->dofs_size < sizeof (dof_relohdr_t) || + sec->dofs_align != sizeof (dof_secidx_t)) { + dtrace_dof_error(dof, "invalid relocation header"); + return (-1); + } + + ss = dtrace_dof_sect(dof, DOF_SECT_STRTAB, dofr->dofr_strtab); + rs = dtrace_dof_sect(dof, DOF_SECT_RELTAB, dofr->dofr_relsec); + ts = dtrace_dof_sect(dof, DOF_SECT_NONE, dofr->dofr_tgtsec); + ts_end = (uintptr_t)ts + sizeof (dof_sec_t); + + if (ss == NULL || rs == NULL || ts == NULL) + return (-1); /* dtrace_dof_error() has been called already */ + + if (rs->dofs_entsize < sizeof (dof_relodesc_t) || + rs->dofs_align != sizeof (uint64_t)) { + dtrace_dof_error(dof, "invalid relocation section"); + return (-1); + } + + r = (dof_relodesc_t *)(uintptr_t)(daddr + rs->dofs_offset); + n = rs->dofs_size / rs->dofs_entsize; + + for (i = 0; i < n; i++) { + uintptr_t taddr = daddr + ts->dofs_offset + r->dofr_offset; + + switch (r->dofr_type) { + case DOF_RELO_NONE: + break; + case DOF_RELO_SETX: + case DOF_RELO_DOFREL: + if (r->dofr_offset >= ts->dofs_size || r->dofr_offset + + sizeof (uint64_t) > ts->dofs_size) { + dtrace_dof_error(dof, "bad relocation offset"); + return (-1); + } + + if (taddr >= (uintptr_t)ts && taddr < ts_end) { + dtrace_dof_error(dof, "bad relocation offset"); + return (-1); + } + + if (!IS_P2ALIGNED(taddr, sizeof (uint64_t))) { + dtrace_dof_error(dof, "misaligned setx relo"); + return (-1); + } + + if (r->dofr_type == DOF_RELO_SETX) + *(uint64_t *)taddr += ubase; + else + *(uint64_t *)taddr += + udaddr + ts->dofs_offset + r->dofr_offset; + break; + default: + dtrace_dof_error(dof, "invalid relocation type"); + return (-1); + } + + r = (dof_relodesc_t *)((uintptr_t)r + rs->dofs_entsize); + } + + return (0); +} + +/* + * The dof_hdr_t passed to dtrace_dof_slurp() should be a partially validated + * header: it should be at the front of a memory region that is at least + * sizeof (dof_hdr_t) in size -- and then at least dof_hdr.dofh_loadsz in + * size. It need not be validated in any other way. + */ +static int +dtrace_dof_slurp(dof_hdr_t *dof, dtrace_vstate_t *vstate, cred_t *cr, + dtrace_enabling_t **enabp, uint64_t ubase, uint64_t udaddr, int noprobes) +{ + uint64_t len = dof->dofh_loadsz, seclen; + uintptr_t daddr = (uintptr_t)dof; + dtrace_ecbdesc_t *ep; + dtrace_enabling_t *enab; + uint_t i; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(dof->dofh_loadsz >= sizeof (dof_hdr_t)); + + /* + * Check the DOF header identification bytes. In addition to checking + * valid settings, we also verify that unused bits/bytes are zeroed so + * we can use them later without fear of regressing existing binaries. + */ + if (bcmp(&dof->dofh_ident[DOF_ID_MAG0], + DOF_MAG_STRING, DOF_MAG_STRLEN) != 0) { + dtrace_dof_error(dof, "DOF magic string mismatch"); + return (-1); + } + + if (dof->dofh_ident[DOF_ID_MODEL] != DOF_MODEL_ILP32 && + dof->dofh_ident[DOF_ID_MODEL] != DOF_MODEL_LP64) { + dtrace_dof_error(dof, "DOF has invalid data model"); + return (-1); + } + + if (dof->dofh_ident[DOF_ID_ENCODING] != DOF_ENCODE_NATIVE) { + dtrace_dof_error(dof, "DOF encoding mismatch"); + return (-1); + } + + if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1 && + dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_2) { + dtrace_dof_error(dof, "DOF version mismatch"); + return (-1); + } + + if (dof->dofh_ident[DOF_ID_DIFVERS] != DIF_VERSION_2) { + dtrace_dof_error(dof, "DOF uses unsupported instruction set"); + return (-1); + } + + if (dof->dofh_ident[DOF_ID_DIFIREG] > DIF_DIR_NREGS) { + dtrace_dof_error(dof, "DOF uses too many integer registers"); + return (-1); + } + + if (dof->dofh_ident[DOF_ID_DIFTREG] > DIF_DTR_NREGS) { + dtrace_dof_error(dof, "DOF uses too many tuple registers"); + return (-1); + } + + for (i = DOF_ID_PAD; i < DOF_ID_SIZE; i++) { + if (dof->dofh_ident[i] != 0) { + dtrace_dof_error(dof, "DOF has invalid ident byte set"); + return (-1); + } + } + + if (dof->dofh_flags & ~DOF_FL_VALID) { + dtrace_dof_error(dof, "DOF has invalid flag bits set"); + return (-1); + } + + if (dof->dofh_secsize == 0) { + dtrace_dof_error(dof, "zero section header size"); + return (-1); + } + + /* + * Check that the section headers don't exceed the amount of DOF + * data. Note that we cast the section size and number of sections + * to uint64_t's to prevent possible overflow in the multiplication. + */ + seclen = (uint64_t)dof->dofh_secnum * (uint64_t)dof->dofh_secsize; + + if (dof->dofh_secoff > len || seclen > len || + dof->dofh_secoff + seclen > len) { + dtrace_dof_error(dof, "truncated section headers"); + return (-1); + } + + if (!IS_P2ALIGNED(dof->dofh_secoff, sizeof (uint64_t))) { + dtrace_dof_error(dof, "misaligned section headers"); + return (-1); + } + + if (!IS_P2ALIGNED(dof->dofh_secsize, sizeof (uint64_t))) { + dtrace_dof_error(dof, "misaligned section size"); + return (-1); + } + + /* + * Take an initial pass through the section headers to be sure that + * the headers don't have stray offsets. If the 'noprobes' flag is + * set, do not permit sections relating to providers, probes, or args. + */ + for (i = 0; i < dof->dofh_secnum; i++) { + dof_sec_t *sec = (dof_sec_t *)(daddr + + (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize); + + if (noprobes) { + switch (sec->dofs_type) { + case DOF_SECT_PROVIDER: + case DOF_SECT_PROBES: + case DOF_SECT_PRARGS: + case DOF_SECT_PROFFS: + dtrace_dof_error(dof, "illegal sections " + "for enabling"); + return (-1); + } + } + + if (DOF_SEC_ISLOADABLE(sec->dofs_type) && + !(sec->dofs_flags & DOF_SECF_LOAD)) { + dtrace_dof_error(dof, "loadable section with load " + "flag unset"); + return (-1); + } + + if (!(sec->dofs_flags & DOF_SECF_LOAD)) + continue; /* just ignore non-loadable sections */ + + if (!ISP2(sec->dofs_align)) { + dtrace_dof_error(dof, "bad section alignment"); + return (-1); + } + + if (sec->dofs_offset & (sec->dofs_align - 1)) { + dtrace_dof_error(dof, "misaligned section"); + return (-1); + } + + if (sec->dofs_offset > len || sec->dofs_size > len || + sec->dofs_offset + sec->dofs_size > len) { + dtrace_dof_error(dof, "corrupt section header"); + return (-1); + } + + if (sec->dofs_type == DOF_SECT_STRTAB && *((char *)daddr + + sec->dofs_offset + sec->dofs_size - 1) != '\0') { + dtrace_dof_error(dof, "non-terminating string table"); + return (-1); + } + } + + /* + * Take a second pass through the sections and locate and perform any + * relocations that are present. We do this after the first pass to + * be sure that all sections have had their headers validated. + */ + for (i = 0; i < dof->dofh_secnum; i++) { + dof_sec_t *sec = (dof_sec_t *)(daddr + + (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize); + + if (!(sec->dofs_flags & DOF_SECF_LOAD)) + continue; /* skip sections that are not loadable */ + + switch (sec->dofs_type) { + case DOF_SECT_URELHDR: + if (dtrace_dof_relocate(dof, sec, ubase, udaddr) != 0) + return (-1); + break; + } + } + + if ((enab = *enabp) == NULL) + enab = *enabp = dtrace_enabling_create(vstate); + + for (i = 0; i < dof->dofh_secnum; i++) { + dof_sec_t *sec = (dof_sec_t *)(daddr + + (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize); + + if (sec->dofs_type != DOF_SECT_ECBDESC) + continue; + + if ((ep = dtrace_dof_ecbdesc(dof, sec, vstate, cr)) == NULL) { + dtrace_enabling_destroy(enab); + *enabp = NULL; + return (-1); + } + + dtrace_enabling_add(enab, ep); + } + + return (0); +} + +/* + * Process DOF for any options. This routine assumes that the DOF has been + * at least processed by dtrace_dof_slurp(). + */ +static int +dtrace_dof_options(dof_hdr_t *dof, dtrace_state_t *state) +{ + int i, rval; + uint32_t entsize; + size_t offs; + dof_optdesc_t *desc; + + for (i = 0; i < dof->dofh_secnum; i++) { + dof_sec_t *sec = (dof_sec_t *)((uintptr_t)dof + + (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize); + + if (sec->dofs_type != DOF_SECT_OPTDESC) + continue; + + if (sec->dofs_align != sizeof (uint64_t)) { + dtrace_dof_error(dof, "bad alignment in " + "option description"); + return (EINVAL); + } + + if ((entsize = sec->dofs_entsize) == 0) { + dtrace_dof_error(dof, "zeroed option entry size"); + return (EINVAL); + } + + if (entsize < sizeof (dof_optdesc_t)) { + dtrace_dof_error(dof, "bad option entry size"); + return (EINVAL); + } + + for (offs = 0; offs < sec->dofs_size; offs += entsize) { + desc = (dof_optdesc_t *)((uintptr_t)dof + + (uintptr_t)sec->dofs_offset + offs); + + if (desc->dofo_strtab != DOF_SECIDX_NONE) { + dtrace_dof_error(dof, "non-zero option string"); + return (EINVAL); + } + + if (desc->dofo_value == DTRACEOPT_UNSET) { + dtrace_dof_error(dof, "unset option"); + return (EINVAL); + } + + if ((rval = dtrace_state_option(state, + desc->dofo_option, desc->dofo_value)) != 0) { + dtrace_dof_error(dof, "rejected option"); + return (rval); + } + } + } + + return (0); +} + +/* + * DTrace Consumer State Functions + */ +static int +dtrace_dstate_init(dtrace_dstate_t *dstate, size_t size) +{ + size_t hashsize, maxper, min, chunksize = dstate->dtds_chunksize; + void *base; + uintptr_t limit; + dtrace_dynvar_t *dvar, *next, *start; + int i; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(dstate->dtds_base == NULL && dstate->dtds_percpu == NULL); + + bzero(dstate, sizeof (dtrace_dstate_t)); + + if ((dstate->dtds_chunksize = chunksize) == 0) + dstate->dtds_chunksize = DTRACE_DYNVAR_CHUNKSIZE; + + VERIFY(dstate->dtds_chunksize < LONG_MAX); + + if (size < (min = dstate->dtds_chunksize + sizeof (dtrace_dynhash_t))) + size = min; + + if ((base = kmem_zalloc(size, KM_NOSLEEP | KM_NORMALPRI)) == NULL) + return (ENOMEM); + + dstate->dtds_size = size; + dstate->dtds_base = base; + dstate->dtds_percpu = kmem_cache_alloc(dtrace_state_cache, KM_SLEEP); + bzero(dstate->dtds_percpu, NCPU * sizeof (dtrace_dstate_percpu_t)); + + hashsize = size / (dstate->dtds_chunksize + sizeof (dtrace_dynhash_t)); + + if (hashsize != 1 && (hashsize & 1)) + hashsize--; + + dstate->dtds_hashsize = hashsize; + dstate->dtds_hash = dstate->dtds_base; + + /* + * Set all of our hash buckets to point to the single sink, and (if + * it hasn't already been set), set the sink's hash value to be the + * sink sentinel value. The sink is needed for dynamic variable + * lookups to know that they have iterated over an entire, valid hash + * chain. + */ + for (i = 0; i < hashsize; i++) + dstate->dtds_hash[i].dtdh_chain = &dtrace_dynhash_sink; + + if (dtrace_dynhash_sink.dtdv_hashval != DTRACE_DYNHASH_SINK) + dtrace_dynhash_sink.dtdv_hashval = DTRACE_DYNHASH_SINK; + + /* + * Determine number of active CPUs. Divide free list evenly among + * active CPUs. + */ + start = (dtrace_dynvar_t *) + ((uintptr_t)base + hashsize * sizeof (dtrace_dynhash_t)); + limit = (uintptr_t)base + size; + + VERIFY((uintptr_t)start < limit); + VERIFY((uintptr_t)start >= (uintptr_t)base); + + maxper = (limit - (uintptr_t)start) / NCPU; + maxper = (maxper / dstate->dtds_chunksize) * dstate->dtds_chunksize; + +#ifndef illumos + CPU_FOREACH(i) { +#else + for (i = 0; i < NCPU; i++) { +#endif + dstate->dtds_percpu[i].dtdsc_free = dvar = start; + + /* + * If we don't even have enough chunks to make it once through + * NCPUs, we're just going to allocate everything to the first + * CPU. And if we're on the last CPU, we're going to allocate + * whatever is left over. In either case, we set the limit to + * be the limit of the dynamic variable space. + */ + if (maxper == 0 || i == NCPU - 1) { + limit = (uintptr_t)base + size; + start = NULL; + } else { + limit = (uintptr_t)start + maxper; + start = (dtrace_dynvar_t *)limit; + } + + VERIFY(limit <= (uintptr_t)base + size); + + for (;;) { + next = (dtrace_dynvar_t *)((uintptr_t)dvar + + dstate->dtds_chunksize); + + if ((uintptr_t)next + dstate->dtds_chunksize >= limit) + break; + + VERIFY((uintptr_t)dvar >= (uintptr_t)base && + (uintptr_t)dvar <= (uintptr_t)base + size); + dvar->dtdv_next = next; + dvar = next; + } + + if (maxper == 0) + break; + } + + return (0); +} + +static void +dtrace_dstate_fini(dtrace_dstate_t *dstate) +{ + ASSERT(MUTEX_HELD(&cpu_lock)); + + if (dstate->dtds_base == NULL) + return; + + kmem_free(dstate->dtds_base, dstate->dtds_size); + kmem_cache_free(dtrace_state_cache, dstate->dtds_percpu); +} + +static void +dtrace_vstate_fini(dtrace_vstate_t *vstate) +{ + /* + * Logical XOR, where are you? + */ + ASSERT((vstate->dtvs_nglobals == 0) ^ (vstate->dtvs_globals != NULL)); + + if (vstate->dtvs_nglobals > 0) { + kmem_free(vstate->dtvs_globals, vstate->dtvs_nglobals * + sizeof (dtrace_statvar_t *)); + } + + if (vstate->dtvs_ntlocals > 0) { + kmem_free(vstate->dtvs_tlocals, vstate->dtvs_ntlocals * + sizeof (dtrace_difv_t)); + } + + ASSERT((vstate->dtvs_nlocals == 0) ^ (vstate->dtvs_locals != NULL)); + + if (vstate->dtvs_nlocals > 0) { + kmem_free(vstate->dtvs_locals, vstate->dtvs_nlocals * + sizeof (dtrace_statvar_t *)); + } +} + +#ifdef illumos +static void +dtrace_state_clean(dtrace_state_t *state) +{ + if (state->dts_activity == DTRACE_ACTIVITY_INACTIVE) + return; + + dtrace_dynvar_clean(&state->dts_vstate.dtvs_dynvars); + dtrace_speculation_clean(state); +} + +static void +dtrace_state_deadman(dtrace_state_t *state) +{ + hrtime_t now; + + dtrace_sync(); + + now = dtrace_gethrtime(); + + if (state != dtrace_anon.dta_state && + now - state->dts_laststatus >= dtrace_deadman_user) + return; + + /* + * We must be sure that dts_alive never appears to be less than the + * value upon entry to dtrace_state_deadman(), and because we lack a + * dtrace_cas64(), we cannot store to it atomically. We thus instead + * store INT64_MAX to it, followed by a memory barrier, followed by + * the new value. This assures that dts_alive never appears to be + * less than its true value, regardless of the order in which the + * stores to the underlying storage are issued. + */ + state->dts_alive = INT64_MAX; + dtrace_membar_producer(); + state->dts_alive = now; +} +#else /* !illumos */ +static void +dtrace_state_clean(void *arg) +{ + dtrace_state_t *state = arg; + dtrace_optval_t *opt = state->dts_options; + + if (state->dts_activity == DTRACE_ACTIVITY_INACTIVE) + return; + + dtrace_dynvar_clean(&state->dts_vstate.dtvs_dynvars); + dtrace_speculation_clean(state); + + callout_reset(&state->dts_cleaner, hz * opt[DTRACEOPT_CLEANRATE] / NANOSEC, + dtrace_state_clean, state); +} + +static void +dtrace_state_deadman(void *arg) +{ + dtrace_state_t *state = arg; + hrtime_t now; + + dtrace_sync(); + + dtrace_debug_output(); + + now = dtrace_gethrtime(); + + if (state != dtrace_anon.dta_state && + now - state->dts_laststatus >= dtrace_deadman_user) + return; + + /* + * We must be sure that dts_alive never appears to be less than the + * value upon entry to dtrace_state_deadman(), and because we lack a + * dtrace_cas64(), we cannot store to it atomically. We thus instead + * store INT64_MAX to it, followed by a memory barrier, followed by + * the new value. This assures that dts_alive never appears to be + * less than its true value, regardless of the order in which the + * stores to the underlying storage are issued. + */ + state->dts_alive = INT64_MAX; + dtrace_membar_producer(); + state->dts_alive = now; + + callout_reset(&state->dts_deadman, hz * dtrace_deadman_interval / NANOSEC, + dtrace_state_deadman, state); +} +#endif /* illumos */ + +static dtrace_state_t * +#ifdef illumos +dtrace_state_create(dev_t *devp, cred_t *cr) +#else +dtrace_state_create(struct cdev *dev, struct ucred *cred __unused) +#endif +{ +#ifdef illumos + minor_t minor; + major_t major; +#else + cred_t *cr = NULL; + int m = 0; +#endif + char c[30]; + dtrace_state_t *state; + dtrace_optval_t *opt; + int bufsize = NCPU * sizeof (dtrace_buffer_t), i; + int cpu_it; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(MUTEX_HELD(&cpu_lock)); + +#ifdef illumos + minor = (minor_t)(uintptr_t)vmem_alloc(dtrace_minor, 1, + VM_BESTFIT | VM_SLEEP); + + if (ddi_soft_state_zalloc(dtrace_softstate, minor) != DDI_SUCCESS) { + vmem_free(dtrace_minor, (void *)(uintptr_t)minor, 1); + return (NULL); + } + + state = ddi_get_soft_state(dtrace_softstate, minor); +#else + if (dev != NULL) { + cr = dev->si_cred; + m = dev2unit(dev); + } + + /* Allocate memory for the state. */ + state = kmem_zalloc(sizeof(dtrace_state_t), KM_SLEEP); +#endif + + state->dts_epid = DTRACE_EPIDNONE + 1; + + (void) snprintf(c, sizeof (c), "dtrace_aggid_%d", m); +#ifdef illumos + state->dts_aggid_arena = vmem_create(c, (void *)1, UINT32_MAX, 1, + NULL, NULL, NULL, 0, VM_SLEEP | VMC_IDENTIFIER); + + if (devp != NULL) { + major = getemajor(*devp); + } else { + major = ddi_driver_major(dtrace_devi); + } + + state->dts_dev = makedevice(major, minor); + + if (devp != NULL) + *devp = state->dts_dev; +#else + state->dts_aggid_arena = new_unrhdr(1, INT_MAX, &dtrace_unr_mtx); + state->dts_dev = dev; +#endif + + /* + * We allocate NCPU buffers. On the one hand, this can be quite + * a bit of memory per instance (nearly 36K on a Starcat). On the + * other hand, it saves an additional memory reference in the probe + * path. + */ + state->dts_buffer = kmem_zalloc(bufsize, KM_SLEEP); + state->dts_aggbuffer = kmem_zalloc(bufsize, KM_SLEEP); + + /* + * Allocate and initialise the per-process per-CPU random state. + * SI_SUB_RANDOM < SI_SUB_DTRACE_ANON therefore entropy device is + * assumed to be seeded at this point (if from Fortuna seed file). + */ + arc4random_buf(&state->dts_rstate[0], 2 * sizeof(uint64_t)); + for (cpu_it = 1; cpu_it < NCPU; cpu_it++) { + /* + * Each CPU is assigned a 2^64 period, non-overlapping + * subsequence. + */ + dtrace_xoroshiro128_plus_jump(state->dts_rstate[cpu_it-1], + state->dts_rstate[cpu_it]); + } + +#ifdef illumos + state->dts_cleaner = CYCLIC_NONE; + state->dts_deadman = CYCLIC_NONE; +#else + callout_init(&state->dts_cleaner, 1); + callout_init(&state->dts_deadman, 1); +#endif + state->dts_vstate.dtvs_state = state; + + for (i = 0; i < DTRACEOPT_MAX; i++) + state->dts_options[i] = DTRACEOPT_UNSET; + + /* + * Set the default options. + */ + opt = state->dts_options; + opt[DTRACEOPT_BUFPOLICY] = DTRACEOPT_BUFPOLICY_SWITCH; + opt[DTRACEOPT_BUFRESIZE] = DTRACEOPT_BUFRESIZE_AUTO; + opt[DTRACEOPT_NSPEC] = dtrace_nspec_default; + opt[DTRACEOPT_SPECSIZE] = dtrace_specsize_default; + opt[DTRACEOPT_CPU] = (dtrace_optval_t)DTRACE_CPUALL; + opt[DTRACEOPT_STRSIZE] = dtrace_strsize_default; + opt[DTRACEOPT_STACKFRAMES] = dtrace_stackframes_default; + opt[DTRACEOPT_USTACKFRAMES] = dtrace_ustackframes_default; + opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_default; + opt[DTRACEOPT_AGGRATE] = dtrace_aggrate_default; + opt[DTRACEOPT_SWITCHRATE] = dtrace_switchrate_default; + opt[DTRACEOPT_STATUSRATE] = dtrace_statusrate_default; + opt[DTRACEOPT_JSTACKFRAMES] = dtrace_jstackframes_default; + opt[DTRACEOPT_JSTACKSTRSIZE] = dtrace_jstackstrsize_default; + + state->dts_activity = DTRACE_ACTIVITY_INACTIVE; + + /* + * Depending on the user credentials, we set flag bits which alter probe + * visibility or the amount of destructiveness allowed. In the case of + * actual anonymous tracing, or the possession of all privileges, all of + * the normal checks are bypassed. + */ + if (cr == NULL || PRIV_POLICY_ONLY(cr, PRIV_ALL, B_FALSE)) { + state->dts_cred.dcr_visible = DTRACE_CRV_ALL; + state->dts_cred.dcr_action = DTRACE_CRA_ALL; + } else { + /* + * Set up the credentials for this instantiation. We take a + * hold on the credential to prevent it from disappearing on + * us; this in turn prevents the zone_t referenced by this + * credential from disappearing. This means that we can + * examine the credential and the zone from probe context. + */ + crhold(cr); + state->dts_cred.dcr_cred = cr; + + /* + * CRA_PROC means "we have *some* privilege for dtrace" and + * unlocks the use of variables like pid, zonename, etc. + */ + if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_USER, B_FALSE) || + PRIV_POLICY_ONLY(cr, PRIV_DTRACE_PROC, B_FALSE)) { + state->dts_cred.dcr_action |= DTRACE_CRA_PROC; + } + + /* + * dtrace_user allows use of syscall and profile providers. + * If the user also has proc_owner and/or proc_zone, we + * extend the scope to include additional visibility and + * destructive power. + */ + if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_USER, B_FALSE)) { + if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE)) { + state->dts_cred.dcr_visible |= + DTRACE_CRV_ALLPROC; + + state->dts_cred.dcr_action |= + DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER; + } + + if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE)) { + state->dts_cred.dcr_visible |= + DTRACE_CRV_ALLZONE; + + state->dts_cred.dcr_action |= + DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE; + } + + /* + * If we have all privs in whatever zone this is, + * we can do destructive things to processes which + * have altered credentials. + */ +#ifdef illumos + if (priv_isequalset(priv_getset(cr, PRIV_EFFECTIVE), + cr->cr_zone->zone_privset)) { + state->dts_cred.dcr_action |= + DTRACE_CRA_PROC_DESTRUCTIVE_CREDCHG; + } +#endif + } + + /* + * Holding the dtrace_kernel privilege also implies that + * the user has the dtrace_user privilege from a visibility + * perspective. But without further privileges, some + * destructive actions are not available. + */ + if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_KERNEL, B_FALSE)) { + /* + * Make all probes in all zones visible. However, + * this doesn't mean that all actions become available + * to all zones. + */ + state->dts_cred.dcr_visible |= DTRACE_CRV_KERNEL | + DTRACE_CRV_ALLPROC | DTRACE_CRV_ALLZONE; + + state->dts_cred.dcr_action |= DTRACE_CRA_KERNEL | + DTRACE_CRA_PROC; + /* + * Holding proc_owner means that destructive actions + * for *this* zone are allowed. + */ + if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE)) + state->dts_cred.dcr_action |= + DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER; + + /* + * Holding proc_zone means that destructive actions + * for this user/group ID in all zones is allowed. + */ + if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE)) + state->dts_cred.dcr_action |= + DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE; + +#ifdef illumos + /* + * If we have all privs in whatever zone this is, + * we can do destructive things to processes which + * have altered credentials. + */ + if (priv_isequalset(priv_getset(cr, PRIV_EFFECTIVE), + cr->cr_zone->zone_privset)) { + state->dts_cred.dcr_action |= + DTRACE_CRA_PROC_DESTRUCTIVE_CREDCHG; + } +#endif + } + + /* + * Holding the dtrace_proc privilege gives control over fasttrap + * and pid providers. We need to grant wider destructive + * privileges in the event that the user has proc_owner and/or + * proc_zone. + */ + if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_PROC, B_FALSE)) { + if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE)) + state->dts_cred.dcr_action |= + DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER; + + if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE)) + state->dts_cred.dcr_action |= + DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE; + } + } + + return (state); +} + +static int +dtrace_state_buffer(dtrace_state_t *state, dtrace_buffer_t *buf, int which) +{ + dtrace_optval_t *opt = state->dts_options, size; + processorid_t cpu = 0;; + int flags = 0, rval, factor, divisor = 1; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(MUTEX_HELD(&cpu_lock)); + ASSERT(which < DTRACEOPT_MAX); + ASSERT(state->dts_activity == DTRACE_ACTIVITY_INACTIVE || + (state == dtrace_anon.dta_state && + state->dts_activity == DTRACE_ACTIVITY_ACTIVE)); + + if (opt[which] == DTRACEOPT_UNSET || opt[which] == 0) + return (0); + + if (opt[DTRACEOPT_CPU] != DTRACEOPT_UNSET) + cpu = opt[DTRACEOPT_CPU]; + + if (which == DTRACEOPT_SPECSIZE) + flags |= DTRACEBUF_NOSWITCH; + + if (which == DTRACEOPT_BUFSIZE) { + if (opt[DTRACEOPT_BUFPOLICY] == DTRACEOPT_BUFPOLICY_RING) + flags |= DTRACEBUF_RING; + + if (opt[DTRACEOPT_BUFPOLICY] == DTRACEOPT_BUFPOLICY_FILL) + flags |= DTRACEBUF_FILL; + + if (state != dtrace_anon.dta_state || + state->dts_activity != DTRACE_ACTIVITY_ACTIVE) + flags |= DTRACEBUF_INACTIVE; + } + + for (size = opt[which]; size >= sizeof (uint64_t); size /= divisor) { + /* + * The size must be 8-byte aligned. If the size is not 8-byte + * aligned, drop it down by the difference. + */ + if (size & (sizeof (uint64_t) - 1)) + size -= size & (sizeof (uint64_t) - 1); + + if (size < state->dts_reserve) { + /* + * Buffers always must be large enough to accommodate + * their prereserved space. We return E2BIG instead + * of ENOMEM in this case to allow for user-level + * software to differentiate the cases. + */ + return (E2BIG); + } + + rval = dtrace_buffer_alloc(buf, size, flags, cpu, &factor); + + if (rval != ENOMEM) { + opt[which] = size; + return (rval); + } + + if (opt[DTRACEOPT_BUFRESIZE] == DTRACEOPT_BUFRESIZE_MANUAL) + return (rval); + + for (divisor = 2; divisor < factor; divisor <<= 1) + continue; + } + + return (ENOMEM); +} + +static int +dtrace_state_buffers(dtrace_state_t *state) +{ + dtrace_speculation_t *spec = state->dts_speculations; + int rval, i; + + if ((rval = dtrace_state_buffer(state, state->dts_buffer, + DTRACEOPT_BUFSIZE)) != 0) + return (rval); + + if ((rval = dtrace_state_buffer(state, state->dts_aggbuffer, + DTRACEOPT_AGGSIZE)) != 0) + return (rval); + + for (i = 0; i < state->dts_nspeculations; i++) { + if ((rval = dtrace_state_buffer(state, + spec[i].dtsp_buffer, DTRACEOPT_SPECSIZE)) != 0) + return (rval); + } + + return (0); +} + +static void +dtrace_state_prereserve(dtrace_state_t *state) +{ + dtrace_ecb_t *ecb; + dtrace_probe_t *probe; + + state->dts_reserve = 0; + + if (state->dts_options[DTRACEOPT_BUFPOLICY] != DTRACEOPT_BUFPOLICY_FILL) + return; + + /* + * If our buffer policy is a "fill" buffer policy, we need to set the + * prereserved space to be the space required by the END probes. + */ + probe = dtrace_probes[dtrace_probeid_end - 1]; + ASSERT(probe != NULL); + + for (ecb = probe->dtpr_ecb; ecb != NULL; ecb = ecb->dte_next) { + if (ecb->dte_state != state) + continue; + + state->dts_reserve += ecb->dte_needed + ecb->dte_alignment; + } +} + +static int +dtrace_state_go(dtrace_state_t *state, processorid_t *cpu) +{ + dtrace_optval_t *opt = state->dts_options, sz, nspec; + dtrace_speculation_t *spec; + dtrace_buffer_t *buf; +#ifdef illumos + cyc_handler_t hdlr; + cyc_time_t when; +#endif + int rval = 0, i, bufsize = NCPU * sizeof (dtrace_buffer_t); + dtrace_icookie_t cookie; + + mutex_enter(&cpu_lock); + mutex_enter(&dtrace_lock); + + if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE) { + rval = EBUSY; + goto out; + } + + /* + * Before we can perform any checks, we must prime all of the + * retained enablings that correspond to this state. + */ + dtrace_enabling_prime(state); + + if (state->dts_destructive && !state->dts_cred.dcr_destructive) { + rval = EACCES; + goto out; + } + + dtrace_state_prereserve(state); + + /* + * Now we want to do is try to allocate our speculations. + * We do not automatically resize the number of speculations; if + * this fails, we will fail the operation. + */ + nspec = opt[DTRACEOPT_NSPEC]; + ASSERT(nspec != DTRACEOPT_UNSET); + + if (nspec > INT_MAX) { + rval = ENOMEM; + goto out; + } + + spec = kmem_zalloc(nspec * sizeof (dtrace_speculation_t), + KM_NOSLEEP | KM_NORMALPRI); + + if (spec == NULL) { + rval = ENOMEM; + goto out; + } + + state->dts_speculations = spec; + state->dts_nspeculations = (int)nspec; + + for (i = 0; i < nspec; i++) { + if ((buf = kmem_zalloc(bufsize, + KM_NOSLEEP | KM_NORMALPRI)) == NULL) { + rval = ENOMEM; + goto err; + } + + spec[i].dtsp_buffer = buf; + } + + if (opt[DTRACEOPT_GRABANON] != DTRACEOPT_UNSET) { + if (dtrace_anon.dta_state == NULL) { + rval = ENOENT; + goto out; + } + + if (state->dts_necbs != 0) { + rval = EALREADY; + goto out; + } + + state->dts_anon = dtrace_anon_grab(); + ASSERT(state->dts_anon != NULL); + state = state->dts_anon; + + /* + * We want "grabanon" to be set in the grabbed state, so we'll + * copy that option value from the grabbing state into the + * grabbed state. + */ + state->dts_options[DTRACEOPT_GRABANON] = + opt[DTRACEOPT_GRABANON]; + + *cpu = dtrace_anon.dta_beganon; + + /* + * If the anonymous state is active (as it almost certainly + * is if the anonymous enabling ultimately matched anything), + * we don't allow any further option processing -- but we + * don't return failure. + */ + if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE) + goto out; + } + + if (opt[DTRACEOPT_AGGSIZE] != DTRACEOPT_UNSET && + opt[DTRACEOPT_AGGSIZE] != 0) { + if (state->dts_aggregations == NULL) { + /* + * We're not going to create an aggregation buffer + * because we don't have any ECBs that contain + * aggregations -- set this option to 0. + */ + opt[DTRACEOPT_AGGSIZE] = 0; + } else { + /* + * If we have an aggregation buffer, we must also have + * a buffer to use as scratch. + */ + if (opt[DTRACEOPT_BUFSIZE] == DTRACEOPT_UNSET || + opt[DTRACEOPT_BUFSIZE] < state->dts_needed) { + opt[DTRACEOPT_BUFSIZE] = state->dts_needed; + } + } + } + + if (opt[DTRACEOPT_SPECSIZE] != DTRACEOPT_UNSET && + opt[DTRACEOPT_SPECSIZE] != 0) { + if (!state->dts_speculates) { + /* + * We're not going to create speculation buffers + * because we don't have any ECBs that actually + * speculate -- set the speculation size to 0. + */ + opt[DTRACEOPT_SPECSIZE] = 0; + } + } + + /* + * The bare minimum size for any buffer that we're actually going to + * do anything to is sizeof (uint64_t). + */ + sz = sizeof (uint64_t); + + if ((state->dts_needed != 0 && opt[DTRACEOPT_BUFSIZE] < sz) || + (state->dts_speculates && opt[DTRACEOPT_SPECSIZE] < sz) || + (state->dts_aggregations != NULL && opt[DTRACEOPT_AGGSIZE] < sz)) { + /* + * A buffer size has been explicitly set to 0 (or to a size + * that will be adjusted to 0) and we need the space -- we + * need to return failure. We return ENOSPC to differentiate + * it from failing to allocate a buffer due to failure to meet + * the reserve (for which we return E2BIG). + */ + rval = ENOSPC; + goto out; + } + + if ((rval = dtrace_state_buffers(state)) != 0) + goto err; + + if ((sz = opt[DTRACEOPT_DYNVARSIZE]) == DTRACEOPT_UNSET) + sz = dtrace_dstate_defsize; + + do { + rval = dtrace_dstate_init(&state->dts_vstate.dtvs_dynvars, sz); + + if (rval == 0) + break; + + if (opt[DTRACEOPT_BUFRESIZE] == DTRACEOPT_BUFRESIZE_MANUAL) + goto err; + } while (sz >>= 1); + + opt[DTRACEOPT_DYNVARSIZE] = sz; + + if (rval != 0) + goto err; + + if (opt[DTRACEOPT_STATUSRATE] > dtrace_statusrate_max) + opt[DTRACEOPT_STATUSRATE] = dtrace_statusrate_max; + + if (opt[DTRACEOPT_CLEANRATE] == 0) + opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_max; + + if (opt[DTRACEOPT_CLEANRATE] < dtrace_cleanrate_min) + opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_min; + + if (opt[DTRACEOPT_CLEANRATE] > dtrace_cleanrate_max) + opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_max; + + state->dts_alive = state->dts_laststatus = dtrace_gethrtime(); +#ifdef illumos + hdlr.cyh_func = (cyc_func_t)dtrace_state_clean; + hdlr.cyh_arg = state; + hdlr.cyh_level = CY_LOW_LEVEL; + + when.cyt_when = 0; + when.cyt_interval = opt[DTRACEOPT_CLEANRATE]; + + state->dts_cleaner = cyclic_add(&hdlr, &when); + + hdlr.cyh_func = (cyc_func_t)dtrace_state_deadman; + hdlr.cyh_arg = state; + hdlr.cyh_level = CY_LOW_LEVEL; + + when.cyt_when = 0; + when.cyt_interval = dtrace_deadman_interval; + + state->dts_deadman = cyclic_add(&hdlr, &when); +#else + callout_reset(&state->dts_cleaner, hz * opt[DTRACEOPT_CLEANRATE] / NANOSEC, + dtrace_state_clean, state); + callout_reset(&state->dts_deadman, hz * dtrace_deadman_interval / NANOSEC, + dtrace_state_deadman, state); +#endif + + state->dts_activity = DTRACE_ACTIVITY_WARMUP; + +#ifdef illumos + if (state->dts_getf != 0 && + !(state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL)) { + /* + * We don't have kernel privs but we have at least one call + * to getf(); we need to bump our zone's count, and (if + * this is the first enabling to have an unprivileged call + * to getf()) we need to hook into closef(). + */ + state->dts_cred.dcr_cred->cr_zone->zone_dtrace_getf++; + + if (dtrace_getf++ == 0) { + ASSERT(dtrace_closef == NULL); + dtrace_closef = dtrace_getf_barrier; + } + } +#endif + + /* + * Now it's time to actually fire the BEGIN probe. We need to disable + * interrupts here both to record the CPU on which we fired the BEGIN + * probe (the data from this CPU will be processed first at user + * level) and to manually activate the buffer for this CPU. + */ + cookie = dtrace_interrupt_disable(); + *cpu = curcpu; + ASSERT(state->dts_buffer[*cpu].dtb_flags & DTRACEBUF_INACTIVE); + state->dts_buffer[*cpu].dtb_flags &= ~DTRACEBUF_INACTIVE; + + dtrace_probe(dtrace_probeid_begin, + (uint64_t)(uintptr_t)state, 0, 0, 0, 0); + dtrace_interrupt_enable(cookie); + /* + * We may have had an exit action from a BEGIN probe; only change our + * state to ACTIVE if we're still in WARMUP. + */ + ASSERT(state->dts_activity == DTRACE_ACTIVITY_WARMUP || + state->dts_activity == DTRACE_ACTIVITY_DRAINING); + + if (state->dts_activity == DTRACE_ACTIVITY_WARMUP) + state->dts_activity = DTRACE_ACTIVITY_ACTIVE; + +#ifdef __FreeBSD__ + /* + * We enable anonymous tracing before APs are started, so we must + * activate buffers using the current CPU. + */ + if (state == dtrace_anon.dta_state) + for (int i = 0; i < NCPU; i++) + dtrace_buffer_activate_cpu(state, i); + else + dtrace_xcall(DTRACE_CPUALL, + (dtrace_xcall_t)dtrace_buffer_activate, state); +#else + /* + * Regardless of whether or not now we're in ACTIVE or DRAINING, we + * want each CPU to transition its principal buffer out of the + * INACTIVE state. Doing this assures that no CPU will suddenly begin + * processing an ECB halfway down a probe's ECB chain; all CPUs will + * atomically transition from processing none of a state's ECBs to + * processing all of them. + */ + dtrace_xcall(DTRACE_CPUALL, + (dtrace_xcall_t)dtrace_buffer_activate, state); +#endif + goto out; + +err: + dtrace_buffer_free(state->dts_buffer); + dtrace_buffer_free(state->dts_aggbuffer); + + if ((nspec = state->dts_nspeculations) == 0) { + ASSERT(state->dts_speculations == NULL); + goto out; + } + + spec = state->dts_speculations; + ASSERT(spec != NULL); + + for (i = 0; i < state->dts_nspeculations; i++) { + if ((buf = spec[i].dtsp_buffer) == NULL) + break; + + dtrace_buffer_free(buf); + kmem_free(buf, bufsize); + } + + kmem_free(spec, nspec * sizeof (dtrace_speculation_t)); + state->dts_nspeculations = 0; + state->dts_speculations = NULL; + +out: + mutex_exit(&dtrace_lock); + mutex_exit(&cpu_lock); + + return (rval); +} + +static int +dtrace_state_stop(dtrace_state_t *state, processorid_t *cpu) +{ + dtrace_icookie_t cookie; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + + if (state->dts_activity != DTRACE_ACTIVITY_ACTIVE && + state->dts_activity != DTRACE_ACTIVITY_DRAINING) + return (EINVAL); + + /* + * We'll set the activity to DTRACE_ACTIVITY_DRAINING, and issue a sync + * to be sure that every CPU has seen it. See below for the details + * on why this is done. + */ + state->dts_activity = DTRACE_ACTIVITY_DRAINING; + dtrace_sync(); + + /* + * By this point, it is impossible for any CPU to be still processing + * with DTRACE_ACTIVITY_ACTIVE. We can thus set our activity to + * DTRACE_ACTIVITY_COOLDOWN and know that we're not racing with any + * other CPU in dtrace_buffer_reserve(). This allows dtrace_probe() + * and callees to know that the activity is DTRACE_ACTIVITY_COOLDOWN + * iff we're in the END probe. + */ + state->dts_activity = DTRACE_ACTIVITY_COOLDOWN; + dtrace_sync(); + ASSERT(state->dts_activity == DTRACE_ACTIVITY_COOLDOWN); + + /* + * Finally, we can release the reserve and call the END probe. We + * disable interrupts across calling the END probe to allow us to + * return the CPU on which we actually called the END probe. This + * allows user-land to be sure that this CPU's principal buffer is + * processed last. + */ + state->dts_reserve = 0; + + cookie = dtrace_interrupt_disable(); + *cpu = curcpu; + dtrace_probe(dtrace_probeid_end, + (uint64_t)(uintptr_t)state, 0, 0, 0, 0); + dtrace_interrupt_enable(cookie); + + state->dts_activity = DTRACE_ACTIVITY_STOPPED; + dtrace_sync(); + +#ifdef illumos + if (state->dts_getf != 0 && + !(state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL)) { + /* + * We don't have kernel privs but we have at least one call + * to getf(); we need to lower our zone's count, and (if + * this is the last enabling to have an unprivileged call + * to getf()) we need to clear the closef() hook. + */ + ASSERT(state->dts_cred.dcr_cred->cr_zone->zone_dtrace_getf > 0); + ASSERT(dtrace_closef == dtrace_getf_barrier); + ASSERT(dtrace_getf > 0); + + state->dts_cred.dcr_cred->cr_zone->zone_dtrace_getf--; + + if (--dtrace_getf == 0) + dtrace_closef = NULL; + } +#endif + + return (0); +} + +static int +dtrace_state_option(dtrace_state_t *state, dtrace_optid_t option, + dtrace_optval_t val) +{ + ASSERT(MUTEX_HELD(&dtrace_lock)); + + if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE) + return (EBUSY); + + if (option >= DTRACEOPT_MAX) + return (EINVAL); + + if (option != DTRACEOPT_CPU && val < 0) + return (EINVAL); + + switch (option) { + case DTRACEOPT_DESTRUCTIVE: + if (dtrace_destructive_disallow) + return (EACCES); + + state->dts_cred.dcr_destructive = 1; + break; + + case DTRACEOPT_BUFSIZE: + case DTRACEOPT_DYNVARSIZE: + case DTRACEOPT_AGGSIZE: + case DTRACEOPT_SPECSIZE: + case DTRACEOPT_STRSIZE: + if (val < 0) + return (EINVAL); + + if (val >= LONG_MAX) { + /* + * If this is an otherwise negative value, set it to + * the highest multiple of 128m less than LONG_MAX. + * Technically, we're adjusting the size without + * regard to the buffer resizing policy, but in fact, + * this has no effect -- if we set the buffer size to + * ~LONG_MAX and the buffer policy is ultimately set to + * be "manual", the buffer allocation is guaranteed to + * fail, if only because the allocation requires two + * buffers. (We set the the size to the highest + * multiple of 128m because it ensures that the size + * will remain a multiple of a megabyte when + * repeatedly halved -- all the way down to 15m.) + */ + val = LONG_MAX - (1 << 27) + 1; + } + } + + state->dts_options[option] = val; + + return (0); +} + +static void +dtrace_state_destroy(dtrace_state_t *state) +{ + dtrace_ecb_t *ecb; + dtrace_vstate_t *vstate = &state->dts_vstate; +#ifdef illumos + minor_t minor = getminor(state->dts_dev); +#endif + int i, bufsize = NCPU * sizeof (dtrace_buffer_t); + dtrace_speculation_t *spec = state->dts_speculations; + int nspec = state->dts_nspeculations; + uint32_t match; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(MUTEX_HELD(&cpu_lock)); + + /* + * First, retract any retained enablings for this state. + */ + dtrace_enabling_retract(state); + ASSERT(state->dts_nretained == 0); + + if (state->dts_activity == DTRACE_ACTIVITY_ACTIVE || + state->dts_activity == DTRACE_ACTIVITY_DRAINING) { + /* + * We have managed to come into dtrace_state_destroy() on a + * hot enabling -- almost certainly because of a disorderly + * shutdown of a consumer. (That is, a consumer that is + * exiting without having called dtrace_stop().) In this case, + * we're going to set our activity to be KILLED, and then + * issue a sync to be sure that everyone is out of probe + * context before we start blowing away ECBs. + */ + state->dts_activity = DTRACE_ACTIVITY_KILLED; + dtrace_sync(); + } + + /* + * Release the credential hold we took in dtrace_state_create(). + */ + if (state->dts_cred.dcr_cred != NULL) + crfree(state->dts_cred.dcr_cred); + + /* + * Now we can safely disable and destroy any enabled probes. Because + * any DTRACE_PRIV_KERNEL probes may actually be slowing our progress + * (especially if they're all enabled), we take two passes through the + * ECBs: in the first, we disable just DTRACE_PRIV_KERNEL probes, and + * in the second we disable whatever is left over. + */ + for (match = DTRACE_PRIV_KERNEL; ; match = 0) { + for (i = 0; i < state->dts_necbs; i++) { + if ((ecb = state->dts_ecbs[i]) == NULL) + continue; + + if (match && ecb->dte_probe != NULL) { + dtrace_probe_t *probe = ecb->dte_probe; + dtrace_provider_t *prov = probe->dtpr_provider; + + if (!(prov->dtpv_priv.dtpp_flags & match)) + continue; + } + + dtrace_ecb_disable(ecb); + dtrace_ecb_destroy(ecb); + } + + if (!match) + break; + } + + /* + * Before we free the buffers, perform one more sync to assure that + * every CPU is out of probe context. + */ + dtrace_sync(); + + dtrace_buffer_free(state->dts_buffer); + dtrace_buffer_free(state->dts_aggbuffer); + + for (i = 0; i < nspec; i++) + dtrace_buffer_free(spec[i].dtsp_buffer); + +#ifdef illumos + if (state->dts_cleaner != CYCLIC_NONE) + cyclic_remove(state->dts_cleaner); + + if (state->dts_deadman != CYCLIC_NONE) + cyclic_remove(state->dts_deadman); +#else + callout_stop(&state->dts_cleaner); + callout_drain(&state->dts_cleaner); + callout_stop(&state->dts_deadman); + callout_drain(&state->dts_deadman); +#endif + + dtrace_dstate_fini(&vstate->dtvs_dynvars); + dtrace_vstate_fini(vstate); + if (state->dts_ecbs != NULL) + kmem_free(state->dts_ecbs, state->dts_necbs * sizeof (dtrace_ecb_t *)); + + if (state->dts_aggregations != NULL) { +#ifdef DEBUG + for (i = 0; i < state->dts_naggregations; i++) + ASSERT(state->dts_aggregations[i] == NULL); +#endif + ASSERT(state->dts_naggregations > 0); + kmem_free(state->dts_aggregations, + state->dts_naggregations * sizeof (dtrace_aggregation_t *)); + } + + kmem_free(state->dts_buffer, bufsize); + kmem_free(state->dts_aggbuffer, bufsize); + + for (i = 0; i < nspec; i++) + kmem_free(spec[i].dtsp_buffer, bufsize); + + if (spec != NULL) + kmem_free(spec, nspec * sizeof (dtrace_speculation_t)); + + dtrace_format_destroy(state); + + if (state->dts_aggid_arena != NULL) { +#ifdef illumos + vmem_destroy(state->dts_aggid_arena); +#else + delete_unrhdr(state->dts_aggid_arena); +#endif + state->dts_aggid_arena = NULL; + } +#ifdef illumos + ddi_soft_state_free(dtrace_softstate, minor); + vmem_free(dtrace_minor, (void *)(uintptr_t)minor, 1); +#endif +} + +/* + * DTrace Anonymous Enabling Functions + */ +static dtrace_state_t * +dtrace_anon_grab(void) +{ + dtrace_state_t *state; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + + if ((state = dtrace_anon.dta_state) == NULL) { + ASSERT(dtrace_anon.dta_enabling == NULL); + return (NULL); + } + + ASSERT(dtrace_anon.dta_enabling != NULL); + ASSERT(dtrace_retained != NULL); + + dtrace_enabling_destroy(dtrace_anon.dta_enabling); + dtrace_anon.dta_enabling = NULL; + dtrace_anon.dta_state = NULL; + + return (state); +} + +static void +dtrace_anon_property(void) +{ + int i, rv; + dtrace_state_t *state; + dof_hdr_t *dof; + char c[32]; /* enough for "dof-data-" + digits */ + + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(MUTEX_HELD(&cpu_lock)); + + for (i = 0; ; i++) { + (void) snprintf(c, sizeof (c), "dof-data-%d", i); + + dtrace_err_verbose = 1; + + if ((dof = dtrace_dof_property(c)) == NULL) { + dtrace_err_verbose = 0; + break; + } + +#ifdef illumos + /* + * We want to create anonymous state, so we need to transition + * the kernel debugger to indicate that DTrace is active. If + * this fails (e.g. because the debugger has modified text in + * some way), we won't continue with the processing. + */ + if (kdi_dtrace_set(KDI_DTSET_DTRACE_ACTIVATE) != 0) { + cmn_err(CE_NOTE, "kernel debugger active; anonymous " + "enabling ignored."); + dtrace_dof_destroy(dof); + break; + } +#endif + + /* + * If we haven't allocated an anonymous state, we'll do so now. + */ + if ((state = dtrace_anon.dta_state) == NULL) { + state = dtrace_state_create(NULL, NULL); + dtrace_anon.dta_state = state; + + if (state == NULL) { + /* + * This basically shouldn't happen: the only + * failure mode from dtrace_state_create() is a + * failure of ddi_soft_state_zalloc() that + * itself should never happen. Still, the + * interface allows for a failure mode, and + * we want to fail as gracefully as possible: + * we'll emit an error message and cease + * processing anonymous state in this case. + */ + cmn_err(CE_WARN, "failed to create " + "anonymous state"); + dtrace_dof_destroy(dof); + break; + } + } + + rv = dtrace_dof_slurp(dof, &state->dts_vstate, CRED(), + &dtrace_anon.dta_enabling, 0, 0, B_TRUE); + + if (rv == 0) + rv = dtrace_dof_options(dof, state); + + dtrace_err_verbose = 0; + dtrace_dof_destroy(dof); + + if (rv != 0) { + /* + * This is malformed DOF; chuck any anonymous state + * that we created. + */ + ASSERT(dtrace_anon.dta_enabling == NULL); + dtrace_state_destroy(state); + dtrace_anon.dta_state = NULL; + break; + } + + ASSERT(dtrace_anon.dta_enabling != NULL); + } + + if (dtrace_anon.dta_enabling != NULL) { + int rval; + + /* + * dtrace_enabling_retain() can only fail because we are + * trying to retain more enablings than are allowed -- but + * we only have one anonymous enabling, and we are guaranteed + * to be allowed at least one retained enabling; we assert + * that dtrace_enabling_retain() returns success. + */ + rval = dtrace_enabling_retain(dtrace_anon.dta_enabling); + ASSERT(rval == 0); + + dtrace_enabling_dump(dtrace_anon.dta_enabling); + } +} + +/* + * DTrace Helper Functions + */ +static void +dtrace_helper_trace(dtrace_helper_action_t *helper, + dtrace_mstate_t *mstate, dtrace_vstate_t *vstate, int where) +{ + uint32_t size, next, nnext, i; + dtrace_helptrace_t *ent, *buffer; + uint16_t flags = cpu_core[curcpu].cpuc_dtrace_flags; + + if ((buffer = dtrace_helptrace_buffer) == NULL) + return; + + ASSERT(vstate->dtvs_nlocals <= dtrace_helptrace_nlocals); + + /* + * What would a tracing framework be without its own tracing + * framework? (Well, a hell of a lot simpler, for starters...) + */ + size = sizeof (dtrace_helptrace_t) + dtrace_helptrace_nlocals * + sizeof (uint64_t) - sizeof (uint64_t); + + /* + * Iterate until we can allocate a slot in the trace buffer. + */ + do { + next = dtrace_helptrace_next; + + if (next + size < dtrace_helptrace_bufsize) { + nnext = next + size; + } else { + nnext = size; + } + } while (dtrace_cas32(&dtrace_helptrace_next, next, nnext) != next); + + /* + * We have our slot; fill it in. + */ + if (nnext == size) { + dtrace_helptrace_wrapped++; + next = 0; + } + + ent = (dtrace_helptrace_t *)((uintptr_t)buffer + next); + ent->dtht_helper = helper; + ent->dtht_where = where; + ent->dtht_nlocals = vstate->dtvs_nlocals; + + ent->dtht_fltoffs = (mstate->dtms_present & DTRACE_MSTATE_FLTOFFS) ? + mstate->dtms_fltoffs : -1; + ent->dtht_fault = DTRACE_FLAGS2FLT(flags); + ent->dtht_illval = cpu_core[curcpu].cpuc_dtrace_illval; + + for (i = 0; i < vstate->dtvs_nlocals; i++) { + dtrace_statvar_t *svar; + + if ((svar = vstate->dtvs_locals[i]) == NULL) + continue; + + ASSERT(svar->dtsv_size >= NCPU * sizeof (uint64_t)); + ent->dtht_locals[i] = + ((uint64_t *)(uintptr_t)svar->dtsv_data)[curcpu]; + } +} + +static uint64_t +dtrace_helper(int which, dtrace_mstate_t *mstate, + dtrace_state_t *state, uint64_t arg0, uint64_t arg1) +{ + uint16_t *flags = &cpu_core[curcpu].cpuc_dtrace_flags; + uint64_t sarg0 = mstate->dtms_arg[0]; + uint64_t sarg1 = mstate->dtms_arg[1]; + uint64_t rval = 0; + dtrace_helpers_t *helpers = curproc->p_dtrace_helpers; + dtrace_helper_action_t *helper; + dtrace_vstate_t *vstate; + dtrace_difo_t *pred; + int i, trace = dtrace_helptrace_buffer != NULL; + + ASSERT(which >= 0 && which < DTRACE_NHELPER_ACTIONS); + + if (helpers == NULL) + return (0); + + if ((helper = helpers->dthps_actions[which]) == NULL) + return (0); + + vstate = &helpers->dthps_vstate; + mstate->dtms_arg[0] = arg0; + mstate->dtms_arg[1] = arg1; + + /* + * Now iterate over each helper. If its predicate evaluates to 'true', + * we'll call the corresponding actions. Note that the below calls + * to dtrace_dif_emulate() may set faults in machine state. This is + * okay: our caller (the outer dtrace_dif_emulate()) will simply plow + * the stored DIF offset with its own (which is the desired behavior). + * Also, note the calls to dtrace_dif_emulate() may allocate scratch + * from machine state; this is okay, too. + */ + for (; helper != NULL; helper = helper->dtha_next) { + if ((pred = helper->dtha_predicate) != NULL) { + if (trace) + dtrace_helper_trace(helper, mstate, vstate, 0); + + if (!dtrace_dif_emulate(pred, mstate, vstate, state)) + goto next; + + if (*flags & CPU_DTRACE_FAULT) + goto err; + } + + for (i = 0; i < helper->dtha_nactions; i++) { + if (trace) + dtrace_helper_trace(helper, + mstate, vstate, i + 1); + + rval = dtrace_dif_emulate(helper->dtha_actions[i], + mstate, vstate, state); + + if (*flags & CPU_DTRACE_FAULT) + goto err; + } + +next: + if (trace) + dtrace_helper_trace(helper, mstate, vstate, + DTRACE_HELPTRACE_NEXT); + } + + if (trace) + dtrace_helper_trace(helper, mstate, vstate, + DTRACE_HELPTRACE_DONE); + + /* + * Restore the arg0 that we saved upon entry. + */ + mstate->dtms_arg[0] = sarg0; + mstate->dtms_arg[1] = sarg1; + + return (rval); + +err: + if (trace) + dtrace_helper_trace(helper, mstate, vstate, + DTRACE_HELPTRACE_ERR); + + /* + * Restore the arg0 that we saved upon entry. + */ + mstate->dtms_arg[0] = sarg0; + mstate->dtms_arg[1] = sarg1; + + return (0); +} + +static void +dtrace_helper_action_destroy(dtrace_helper_action_t *helper, + dtrace_vstate_t *vstate) +{ + int i; + + if (helper->dtha_predicate != NULL) + dtrace_difo_release(helper->dtha_predicate, vstate); + + for (i = 0; i < helper->dtha_nactions; i++) { + ASSERT(helper->dtha_actions[i] != NULL); + dtrace_difo_release(helper->dtha_actions[i], vstate); + } + + kmem_free(helper->dtha_actions, + helper->dtha_nactions * sizeof (dtrace_difo_t *)); + kmem_free(helper, sizeof (dtrace_helper_action_t)); +} + +static int +dtrace_helper_destroygen(dtrace_helpers_t *help, int gen) +{ + proc_t *p = curproc; + dtrace_vstate_t *vstate; + int i; + + if (help == NULL) + help = p->p_dtrace_helpers; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + + if (help == NULL || gen > help->dthps_generation) + return (EINVAL); + + vstate = &help->dthps_vstate; + + for (i = 0; i < DTRACE_NHELPER_ACTIONS; i++) { + dtrace_helper_action_t *last = NULL, *h, *next; + + for (h = help->dthps_actions[i]; h != NULL; h = next) { + next = h->dtha_next; + + if (h->dtha_generation == gen) { + if (last != NULL) { + last->dtha_next = next; + } else { + help->dthps_actions[i] = next; + } + + dtrace_helper_action_destroy(h, vstate); + } else { + last = h; + } + } + } + + /* + * Interate until we've cleared out all helper providers with the + * given generation number. + */ + for (;;) { + dtrace_helper_provider_t *prov; + + /* + * Look for a helper provider with the right generation. We + * have to start back at the beginning of the list each time + * because we drop dtrace_lock. It's unlikely that we'll make + * more than two passes. + */ + for (i = 0; i < help->dthps_nprovs; i++) { + prov = help->dthps_provs[i]; + + if (prov->dthp_generation == gen) + break; + } + + /* + * If there were no matches, we're done. + */ + if (i == help->dthps_nprovs) + break; + + /* + * Move the last helper provider into this slot. + */ + help->dthps_nprovs--; + help->dthps_provs[i] = help->dthps_provs[help->dthps_nprovs]; + help->dthps_provs[help->dthps_nprovs] = NULL; + + mutex_exit(&dtrace_lock); + + /* + * If we have a meta provider, remove this helper provider. + */ + mutex_enter(&dtrace_meta_lock); + if (dtrace_meta_pid != NULL) { + ASSERT(dtrace_deferred_pid == NULL); + dtrace_helper_provider_remove(&prov->dthp_prov, + p->p_pid); + } + mutex_exit(&dtrace_meta_lock); + + dtrace_helper_provider_destroy(prov); + + mutex_enter(&dtrace_lock); + } + + return (0); +} + +static int +dtrace_helper_validate(dtrace_helper_action_t *helper) +{ + int err = 0, i; + dtrace_difo_t *dp; + + if ((dp = helper->dtha_predicate) != NULL) + err += dtrace_difo_validate_helper(dp); + + for (i = 0; i < helper->dtha_nactions; i++) + err += dtrace_difo_validate_helper(helper->dtha_actions[i]); + + return (err == 0); +} + +static int +dtrace_helper_action_add(int which, dtrace_ecbdesc_t *ep, + dtrace_helpers_t *help) +{ + dtrace_helper_action_t *helper, *last; + dtrace_actdesc_t *act; + dtrace_vstate_t *vstate; + dtrace_predicate_t *pred; + int count = 0, nactions = 0, i; + + if (which < 0 || which >= DTRACE_NHELPER_ACTIONS) + return (EINVAL); + + last = help->dthps_actions[which]; + vstate = &help->dthps_vstate; + + for (count = 0; last != NULL; last = last->dtha_next) { + count++; + if (last->dtha_next == NULL) + break; + } + + /* + * If we already have dtrace_helper_actions_max helper actions for this + * helper action type, we'll refuse to add a new one. + */ + if (count >= dtrace_helper_actions_max) + return (ENOSPC); + + helper = kmem_zalloc(sizeof (dtrace_helper_action_t), KM_SLEEP); + helper->dtha_generation = help->dthps_generation; + + if ((pred = ep->dted_pred.dtpdd_predicate) != NULL) { + ASSERT(pred->dtp_difo != NULL); + dtrace_difo_hold(pred->dtp_difo); + helper->dtha_predicate = pred->dtp_difo; + } + + for (act = ep->dted_action; act != NULL; act = act->dtad_next) { + if (act->dtad_kind != DTRACEACT_DIFEXPR) + goto err; + + if (act->dtad_difo == NULL) + goto err; + + nactions++; + } + + helper->dtha_actions = kmem_zalloc(sizeof (dtrace_difo_t *) * + (helper->dtha_nactions = nactions), KM_SLEEP); + + for (act = ep->dted_action, i = 0; act != NULL; act = act->dtad_next) { + dtrace_difo_hold(act->dtad_difo); + helper->dtha_actions[i++] = act->dtad_difo; + } + + if (!dtrace_helper_validate(helper)) + goto err; + + if (last == NULL) { + help->dthps_actions[which] = helper; + } else { + last->dtha_next = helper; + } + + if (vstate->dtvs_nlocals > dtrace_helptrace_nlocals) { + dtrace_helptrace_nlocals = vstate->dtvs_nlocals; + dtrace_helptrace_next = 0; + } + + return (0); +err: + dtrace_helper_action_destroy(helper, vstate); + return (EINVAL); +} + +static void +dtrace_helper_provider_register(proc_t *p, dtrace_helpers_t *help, + dof_helper_t *dofhp) +{ + ASSERT(MUTEX_NOT_HELD(&dtrace_lock)); + + mutex_enter(&dtrace_meta_lock); + mutex_enter(&dtrace_lock); + + if (!dtrace_attached() || dtrace_meta_pid == NULL) { + /* + * If the dtrace module is loaded but not attached, or if + * there aren't isn't a meta provider registered to deal with + * these provider descriptions, we need to postpone creating + * the actual providers until later. + */ + + if (help->dthps_next == NULL && help->dthps_prev == NULL && + dtrace_deferred_pid != help) { + help->dthps_deferred = 1; + help->dthps_pid = p->p_pid; + help->dthps_next = dtrace_deferred_pid; + help->dthps_prev = NULL; + if (dtrace_deferred_pid != NULL) + dtrace_deferred_pid->dthps_prev = help; + dtrace_deferred_pid = help; + } + + mutex_exit(&dtrace_lock); + + } else if (dofhp != NULL) { + /* + * If the dtrace module is loaded and we have a particular + * helper provider description, pass that off to the + * meta provider. + */ + + mutex_exit(&dtrace_lock); + + dtrace_helper_provide(dofhp, p->p_pid); + + } else { + /* + * Otherwise, just pass all the helper provider descriptions + * off to the meta provider. + */ + + int i; + mutex_exit(&dtrace_lock); + + for (i = 0; i < help->dthps_nprovs; i++) { + dtrace_helper_provide(&help->dthps_provs[i]->dthp_prov, + p->p_pid); + } + } + + mutex_exit(&dtrace_meta_lock); +} + +static int +dtrace_helper_provider_add(dof_helper_t *dofhp, dtrace_helpers_t *help, int gen) +{ + dtrace_helper_provider_t *hprov, **tmp_provs; + uint_t tmp_maxprovs, i; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(help != NULL); + + /* + * If we already have dtrace_helper_providers_max helper providers, + * we're refuse to add a new one. + */ + if (help->dthps_nprovs >= dtrace_helper_providers_max) + return (ENOSPC); + + /* + * Check to make sure this isn't a duplicate. + */ + for (i = 0; i < help->dthps_nprovs; i++) { + if (dofhp->dofhp_addr == + help->dthps_provs[i]->dthp_prov.dofhp_addr) + return (EALREADY); + } + + hprov = kmem_zalloc(sizeof (dtrace_helper_provider_t), KM_SLEEP); + hprov->dthp_prov = *dofhp; + hprov->dthp_ref = 1; + hprov->dthp_generation = gen; + + /* + * Allocate a bigger table for helper providers if it's already full. + */ + if (help->dthps_maxprovs == help->dthps_nprovs) { + tmp_maxprovs = help->dthps_maxprovs; + tmp_provs = help->dthps_provs; + + if (help->dthps_maxprovs == 0) + help->dthps_maxprovs = 2; + else + help->dthps_maxprovs *= 2; + if (help->dthps_maxprovs > dtrace_helper_providers_max) + help->dthps_maxprovs = dtrace_helper_providers_max; + + ASSERT(tmp_maxprovs < help->dthps_maxprovs); + + help->dthps_provs = kmem_zalloc(help->dthps_maxprovs * + sizeof (dtrace_helper_provider_t *), KM_SLEEP); + + if (tmp_provs != NULL) { + bcopy(tmp_provs, help->dthps_provs, tmp_maxprovs * + sizeof (dtrace_helper_provider_t *)); + kmem_free(tmp_provs, tmp_maxprovs * + sizeof (dtrace_helper_provider_t *)); + } + } + + help->dthps_provs[help->dthps_nprovs] = hprov; + help->dthps_nprovs++; + + return (0); +} + +static void +dtrace_helper_provider_destroy(dtrace_helper_provider_t *hprov) +{ + mutex_enter(&dtrace_lock); + + if (--hprov->dthp_ref == 0) { + dof_hdr_t *dof; + mutex_exit(&dtrace_lock); + dof = (dof_hdr_t *)(uintptr_t)hprov->dthp_prov.dofhp_dof; + dtrace_dof_destroy(dof); + kmem_free(hprov, sizeof (dtrace_helper_provider_t)); + } else { + mutex_exit(&dtrace_lock); + } +} + +static int +dtrace_helper_provider_validate(dof_hdr_t *dof, dof_sec_t *sec) +{ + uintptr_t daddr = (uintptr_t)dof; + dof_sec_t *str_sec, *prb_sec, *arg_sec, *off_sec, *enoff_sec; + dof_provider_t *provider; + dof_probe_t *probe; + uint8_t *arg; + char *strtab, *typestr; + dof_stridx_t typeidx; + size_t typesz; + uint_t nprobes, j, k; + + ASSERT(sec->dofs_type == DOF_SECT_PROVIDER); + + if (sec->dofs_offset & (sizeof (uint_t) - 1)) { + dtrace_dof_error(dof, "misaligned section offset"); + return (-1); + } + + /* + * The section needs to be large enough to contain the DOF provider + * structure appropriate for the given version. + */ + if (sec->dofs_size < + ((dof->dofh_ident[DOF_ID_VERSION] == DOF_VERSION_1) ? + offsetof(dof_provider_t, dofpv_prenoffs) : + sizeof (dof_provider_t))) { + dtrace_dof_error(dof, "provider section too small"); + return (-1); + } + + provider = (dof_provider_t *)(uintptr_t)(daddr + sec->dofs_offset); + str_sec = dtrace_dof_sect(dof, DOF_SECT_STRTAB, provider->dofpv_strtab); + prb_sec = dtrace_dof_sect(dof, DOF_SECT_PROBES, provider->dofpv_probes); + arg_sec = dtrace_dof_sect(dof, DOF_SECT_PRARGS, provider->dofpv_prargs); + off_sec = dtrace_dof_sect(dof, DOF_SECT_PROFFS, provider->dofpv_proffs); + + if (str_sec == NULL || prb_sec == NULL || + arg_sec == NULL || off_sec == NULL) + return (-1); + + enoff_sec = NULL; + + if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1 && + provider->dofpv_prenoffs != DOF_SECT_NONE && + (enoff_sec = dtrace_dof_sect(dof, DOF_SECT_PRENOFFS, + provider->dofpv_prenoffs)) == NULL) + return (-1); + + strtab = (char *)(uintptr_t)(daddr + str_sec->dofs_offset); + + if (provider->dofpv_name >= str_sec->dofs_size || + strlen(strtab + provider->dofpv_name) >= DTRACE_PROVNAMELEN) { + dtrace_dof_error(dof, "invalid provider name"); + return (-1); + } + + if (prb_sec->dofs_entsize == 0 || + prb_sec->dofs_entsize > prb_sec->dofs_size) { + dtrace_dof_error(dof, "invalid entry size"); + return (-1); + } + + if (prb_sec->dofs_entsize & (sizeof (uintptr_t) - 1)) { + dtrace_dof_error(dof, "misaligned entry size"); + return (-1); + } + + if (off_sec->dofs_entsize != sizeof (uint32_t)) { + dtrace_dof_error(dof, "invalid entry size"); + return (-1); + } + + if (off_sec->dofs_offset & (sizeof (uint32_t) - 1)) { + dtrace_dof_error(dof, "misaligned section offset"); + return (-1); + } + + if (arg_sec->dofs_entsize != sizeof (uint8_t)) { + dtrace_dof_error(dof, "invalid entry size"); + return (-1); + } + + arg = (uint8_t *)(uintptr_t)(daddr + arg_sec->dofs_offset); + + nprobes = prb_sec->dofs_size / prb_sec->dofs_entsize; + + /* + * Take a pass through the probes to check for errors. + */ + for (j = 0; j < nprobes; j++) { + probe = (dof_probe_t *)(uintptr_t)(daddr + + prb_sec->dofs_offset + j * prb_sec->dofs_entsize); + + if (probe->dofpr_func >= str_sec->dofs_size) { + dtrace_dof_error(dof, "invalid function name"); + return (-1); + } + + if (strlen(strtab + probe->dofpr_func) >= DTRACE_FUNCNAMELEN) { + dtrace_dof_error(dof, "function name too long"); + /* + * Keep going if the function name is too long. + * Unlike provider and probe names, we cannot reasonably + * impose restrictions on function names, since they're + * a property of the code being instrumented. We will + * skip this probe in dtrace_helper_provide_one(). + */ + } + + if (probe->dofpr_name >= str_sec->dofs_size || + strlen(strtab + probe->dofpr_name) >= DTRACE_NAMELEN) { + dtrace_dof_error(dof, "invalid probe name"); + return (-1); + } + + /* + * The offset count must not wrap the index, and the offsets + * must also not overflow the section's data. + */ + if (probe->dofpr_offidx + probe->dofpr_noffs < + probe->dofpr_offidx || + (probe->dofpr_offidx + probe->dofpr_noffs) * + off_sec->dofs_entsize > off_sec->dofs_size) { + dtrace_dof_error(dof, "invalid probe offset"); + return (-1); + } + + if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1) { + /* + * If there's no is-enabled offset section, make sure + * there aren't any is-enabled offsets. Otherwise + * perform the same checks as for probe offsets + * (immediately above). + */ + if (enoff_sec == NULL) { + if (probe->dofpr_enoffidx != 0 || + probe->dofpr_nenoffs != 0) { + dtrace_dof_error(dof, "is-enabled " + "offsets with null section"); + return (-1); + } + } else if (probe->dofpr_enoffidx + + probe->dofpr_nenoffs < probe->dofpr_enoffidx || + (probe->dofpr_enoffidx + probe->dofpr_nenoffs) * + enoff_sec->dofs_entsize > enoff_sec->dofs_size) { + dtrace_dof_error(dof, "invalid is-enabled " + "offset"); + return (-1); + } + + if (probe->dofpr_noffs + probe->dofpr_nenoffs == 0) { + dtrace_dof_error(dof, "zero probe and " + "is-enabled offsets"); + return (-1); + } + } else if (probe->dofpr_noffs == 0) { + dtrace_dof_error(dof, "zero probe offsets"); + return (-1); + } + + if (probe->dofpr_argidx + probe->dofpr_xargc < + probe->dofpr_argidx || + (probe->dofpr_argidx + probe->dofpr_xargc) * + arg_sec->dofs_entsize > arg_sec->dofs_size) { + dtrace_dof_error(dof, "invalid args"); + return (-1); + } + + typeidx = probe->dofpr_nargv; + typestr = strtab + probe->dofpr_nargv; + for (k = 0; k < probe->dofpr_nargc; k++) { + if (typeidx >= str_sec->dofs_size) { + dtrace_dof_error(dof, "bad " + "native argument type"); + return (-1); + } + + typesz = strlen(typestr) + 1; + if (typesz > DTRACE_ARGTYPELEN) { + dtrace_dof_error(dof, "native " + "argument type too long"); + return (-1); + } + typeidx += typesz; + typestr += typesz; + } + + typeidx = probe->dofpr_xargv; + typestr = strtab + probe->dofpr_xargv; + for (k = 0; k < probe->dofpr_xargc; k++) { + if (arg[probe->dofpr_argidx + k] > probe->dofpr_nargc) { + dtrace_dof_error(dof, "bad " + "native argument index"); + return (-1); + } + + if (typeidx >= str_sec->dofs_size) { + dtrace_dof_error(dof, "bad " + "translated argument type"); + return (-1); + } + + typesz = strlen(typestr) + 1; + if (typesz > DTRACE_ARGTYPELEN) { + dtrace_dof_error(dof, "translated argument " + "type too long"); + return (-1); + } + + typeidx += typesz; + typestr += typesz; + } + } + + return (0); +} + +static int +dtrace_helper_slurp(dof_hdr_t *dof, dof_helper_t *dhp, struct proc *p) +{ + dtrace_helpers_t *help; + dtrace_vstate_t *vstate; + dtrace_enabling_t *enab = NULL; + int i, gen, rv, nhelpers = 0, nprovs = 0, destroy = 1; + uintptr_t daddr = (uintptr_t)dof; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + + if ((help = p->p_dtrace_helpers) == NULL) + help = dtrace_helpers_create(p); + + vstate = &help->dthps_vstate; + + if ((rv = dtrace_dof_slurp(dof, vstate, NULL, &enab, dhp->dofhp_addr, + dhp->dofhp_dof, B_FALSE)) != 0) { + dtrace_dof_destroy(dof); + return (rv); + } + + /* + * Look for helper providers and validate their descriptions. + */ + for (i = 0; i < dof->dofh_secnum; i++) { + dof_sec_t *sec = (dof_sec_t *)(uintptr_t)(daddr + + dof->dofh_secoff + i * dof->dofh_secsize); + + if (sec->dofs_type != DOF_SECT_PROVIDER) + continue; + + if (dtrace_helper_provider_validate(dof, sec) != 0) { + dtrace_enabling_destroy(enab); + dtrace_dof_destroy(dof); + return (-1); + } + + nprovs++; + } + + /* + * Now we need to walk through the ECB descriptions in the enabling. + */ + for (i = 0; i < enab->dten_ndesc; i++) { + dtrace_ecbdesc_t *ep = enab->dten_desc[i]; + dtrace_probedesc_t *desc = &ep->dted_probe; + + if (strcmp(desc->dtpd_provider, "dtrace") != 0) + continue; + + if (strcmp(desc->dtpd_mod, "helper") != 0) + continue; + + if (strcmp(desc->dtpd_func, "ustack") != 0) + continue; + + if ((rv = dtrace_helper_action_add(DTRACE_HELPER_ACTION_USTACK, + ep, help)) != 0) { + /* + * Adding this helper action failed -- we are now going + * to rip out the entire generation and return failure. + */ + (void) dtrace_helper_destroygen(help, + help->dthps_generation); + dtrace_enabling_destroy(enab); + dtrace_dof_destroy(dof); + return (-1); + } + + nhelpers++; + } + + if (nhelpers < enab->dten_ndesc) + dtrace_dof_error(dof, "unmatched helpers"); + + gen = help->dthps_generation++; + dtrace_enabling_destroy(enab); + + if (nprovs > 0) { + /* + * Now that this is in-kernel, we change the sense of the + * members: dofhp_dof denotes the in-kernel copy of the DOF + * and dofhp_addr denotes the address at user-level. + */ + dhp->dofhp_addr = dhp->dofhp_dof; + dhp->dofhp_dof = (uint64_t)(uintptr_t)dof; + + if (dtrace_helper_provider_add(dhp, help, gen) == 0) { + mutex_exit(&dtrace_lock); + dtrace_helper_provider_register(p, help, dhp); + mutex_enter(&dtrace_lock); + + destroy = 0; + } + } + + if (destroy) + dtrace_dof_destroy(dof); + + return (gen); +} + +static dtrace_helpers_t * +dtrace_helpers_create(proc_t *p) +{ + dtrace_helpers_t *help; + + ASSERT(MUTEX_HELD(&dtrace_lock)); + ASSERT(p->p_dtrace_helpers == NULL); + + help = kmem_zalloc(sizeof (dtrace_helpers_t), KM_SLEEP); + help->dthps_actions = kmem_zalloc(sizeof (dtrace_helper_action_t *) * + DTRACE_NHELPER_ACTIONS, KM_SLEEP); + + p->p_dtrace_helpers = help; + dtrace_helpers++; + + return (help); +} + +#ifdef illumos +static +#endif +void +dtrace_helpers_destroy(proc_t *p) +{ + dtrace_helpers_t *help; + dtrace_vstate_t *vstate; +#ifdef illumos + proc_t *p = curproc; +#endif + int i; + + mutex_enter(&dtrace_lock); + + ASSERT(p->p_dtrace_helpers != NULL); + ASSERT(dtrace_helpers > 0); + + help = p->p_dtrace_helpers; + vstate = &help->dthps_vstate; + + /* + * We're now going to lose the help from this process. + */ + p->p_dtrace_helpers = NULL; + dtrace_sync(); + + /* + * Destory the helper actions. + */ + for (i = 0; i < DTRACE_NHELPER_ACTIONS; i++) { + dtrace_helper_action_t *h, *next; + + for (h = help->dthps_actions[i]; h != NULL; h = next) { + next = h->dtha_next; + dtrace_helper_action_destroy(h, vstate); + h = next; + } + } + + mutex_exit(&dtrace_lock); + + /* + * Destroy the helper providers. + */ + if (help->dthps_maxprovs > 0) { + mutex_enter(&dtrace_meta_lock); + if (dtrace_meta_pid != NULL) { + ASSERT(dtrace_deferred_pid == NULL); + + for (i = 0; i < help->dthps_nprovs; i++) { + dtrace_helper_provider_remove( + &help->dthps_provs[i]->dthp_prov, p->p_pid); + } + } else { + mutex_enter(&dtrace_lock); + ASSERT(help->dthps_deferred == 0 || + help->dthps_next != NULL || + help->dthps_prev != NULL || + help == dtrace_deferred_pid); + + /* + * Remove the helper from the deferred list. + */ + if (help->dthps_next != NULL) + help->dthps_next->dthps_prev = help->dthps_prev; + if (help->dthps_prev != NULL) + help->dthps_prev->dthps_next = help->dthps_next; + if (dtrace_deferred_pid == help) { + dtrace_deferred_pid = help->dthps_next; + ASSERT(help->dthps_prev == NULL); + } + + mutex_exit(&dtrace_lock); + } + + mutex_exit(&dtrace_meta_lock); + + for (i = 0; i < help->dthps_nprovs; i++) { + dtrace_helper_provider_destroy(help->dthps_provs[i]); + } + + kmem_free(help->dthps_provs, help->dthps_maxprovs * + sizeof (dtrace_helper_provider_t *)); + } + + mutex_enter(&dtrace_lock); + + dtrace_vstate_fini(&help->dthps_vstate); + kmem_free(help->dthps_actions, + sizeof (dtrace_helper_action_t *) * DTRACE_NHELPER_ACTIONS); + kmem_free(help, sizeof (dtrace_helpers_t)); + + --dtrace_helpers; + mutex_exit(&dtrace_lock); +} + +#ifdef illumos +static +#endif +void +dtrace_helpers_duplicate(proc_t *from, proc_t *to) +{ + dtrace_helpers_t *help, *newhelp; + dtrace_helper_action_t *helper, *new, *last; + dtrace_difo_t *dp; + dtrace_vstate_t *vstate; + int i, j, sz, hasprovs = 0; + + mutex_enter(&dtrace_lock); + ASSERT(from->p_dtrace_helpers != NULL); + ASSERT(dtrace_helpers > 0); + + help = from->p_dtrace_helpers; + newhelp = dtrace_helpers_create(to); + ASSERT(to->p_dtrace_helpers != NULL); + + newhelp->dthps_generation = help->dthps_generation; + vstate = &newhelp->dthps_vstate; + + /* + * Duplicate the helper actions. + */ + for (i = 0; i < DTRACE_NHELPER_ACTIONS; i++) { + if ((helper = help->dthps_actions[i]) == NULL) + continue; + + for (last = NULL; helper != NULL; helper = helper->dtha_next) { + new = kmem_zalloc(sizeof (dtrace_helper_action_t), + KM_SLEEP); + new->dtha_generation = helper->dtha_generation; + + if ((dp = helper->dtha_predicate) != NULL) { + dp = dtrace_difo_duplicate(dp, vstate); + new->dtha_predicate = dp; + } + + new->dtha_nactions = helper->dtha_nactions; + sz = sizeof (dtrace_difo_t *) * new->dtha_nactions; + new->dtha_actions = kmem_alloc(sz, KM_SLEEP); + + for (j = 0; j < new->dtha_nactions; j++) { + dtrace_difo_t *dp = helper->dtha_actions[j]; + + ASSERT(dp != NULL); + dp = dtrace_difo_duplicate(dp, vstate); + new->dtha_actions[j] = dp; + } + + if (last != NULL) { + last->dtha_next = new; + } else { + newhelp->dthps_actions[i] = new; + } + + last = new; + } + } + + /* + * Duplicate the helper providers and register them with the + * DTrace framework. + */ + if (help->dthps_nprovs > 0) { + newhelp->dthps_nprovs = help->dthps_nprovs; + newhelp->dthps_maxprovs = help->dthps_nprovs; + newhelp->dthps_provs = kmem_alloc(newhelp->dthps_nprovs * + sizeof (dtrace_helper_provider_t *), KM_SLEEP); + for (i = 0; i < newhelp->dthps_nprovs; i++) { + newhelp->dthps_provs[i] = help->dthps_provs[i]; + newhelp->dthps_provs[i]->dthp_ref++; + } + + hasprovs = 1; + } + + mutex_exit(&dtrace_lock); + + if (hasprovs) + dtrace_helper_provider_register(to, newhelp, NULL); +} + +/* + * DTrace Hook Functions + */ +static void +dtrace_module_loaded(modctl_t *ctl) +{ + dtrace_provider_t *prv; + + mutex_enter(&dtrace_provider_lock); +#ifdef illumos + mutex_enter(&mod_lock); +#endif + +#ifdef illumos + ASSERT(ctl->mod_busy); +#endif + + /* + * We're going to call each providers per-module provide operation + * specifying only this module. + */ + for (prv = dtrace_provider; prv != NULL; prv = prv->dtpv_next) + prv->dtpv_pops.dtps_provide_module(prv->dtpv_arg, ctl); + +#ifdef illumos + mutex_exit(&mod_lock); +#endif + mutex_exit(&dtrace_provider_lock); + + /* + * If we have any retained enablings, we need to match against them. + * Enabling probes requires that cpu_lock be held, and we cannot hold + * cpu_lock here -- it is legal for cpu_lock to be held when loading a + * module. (In particular, this happens when loading scheduling + * classes.) So if we have any retained enablings, we need to dispatch + * our task queue to do the match for us. + */ + mutex_enter(&dtrace_lock); + + if (dtrace_retained == NULL) { + mutex_exit(&dtrace_lock); + return; + } + + (void) taskq_dispatch(dtrace_taskq, + (task_func_t *)dtrace_enabling_matchall, NULL, TQ_SLEEP); + + mutex_exit(&dtrace_lock); + + /* + * And now, for a little heuristic sleaze: in general, we want to + * match modules as soon as they load. However, we cannot guarantee + * this, because it would lead us to the lock ordering violation + * outlined above. The common case, of course, is that cpu_lock is + * _not_ held -- so we delay here for a clock tick, hoping that that's + * long enough for the task queue to do its work. If it's not, it's + * not a serious problem -- it just means that the module that we + * just loaded may not be immediately instrumentable. + */ + delay(1); +} + +static void +#ifdef illumos +dtrace_module_unloaded(modctl_t *ctl) +#else +dtrace_module_unloaded(modctl_t *ctl, int *error) +#endif +{ + dtrace_probe_t template, *probe, *first, *next; + dtrace_provider_t *prov; +#ifndef illumos + char modname[DTRACE_MODNAMELEN]; + size_t len; +#endif + +#ifdef illumos + template.dtpr_mod = ctl->mod_modname; +#else + /* Handle the fact that ctl->filename may end in ".ko". */ + strlcpy(modname, ctl->filename, sizeof(modname)); + len = strlen(ctl->filename); + if (len > 3 && strcmp(modname + len - 3, ".ko") == 0) + modname[len - 3] = '\0'; + template.dtpr_mod = modname; +#endif + + mutex_enter(&dtrace_provider_lock); +#ifdef illumos + mutex_enter(&mod_lock); +#endif + mutex_enter(&dtrace_lock); + +#ifndef illumos + if (ctl->nenabled > 0) { + /* Don't allow unloads if a probe is enabled. */ + mutex_exit(&dtrace_provider_lock); + mutex_exit(&dtrace_lock); + *error = -1; + printf( + "kldunload: attempt to unload module that has DTrace probes enabled\n"); + return; + } +#endif + + if (dtrace_bymod == NULL) { + /* + * The DTrace module is loaded (obviously) but not attached; + * we don't have any work to do. + */ + mutex_exit(&dtrace_provider_lock); +#ifdef illumos + mutex_exit(&mod_lock); +#endif + mutex_exit(&dtrace_lock); + return; + } + + for (probe = first = dtrace_hash_lookup(dtrace_bymod, &template); + probe != NULL; probe = probe->dtpr_nextmod) { + if (probe->dtpr_ecb != NULL) { + mutex_exit(&dtrace_provider_lock); +#ifdef illumos + mutex_exit(&mod_lock); +#endif + mutex_exit(&dtrace_lock); + + /* + * This shouldn't _actually_ be possible -- we're + * unloading a module that has an enabled probe in it. + * (It's normally up to the provider to make sure that + * this can't happen.) However, because dtps_enable() + * doesn't have a failure mode, there can be an + * enable/unload race. Upshot: we don't want to + * assert, but we're not going to disable the + * probe, either. + */ + if (dtrace_err_verbose) { +#ifdef illumos + cmn_err(CE_WARN, "unloaded module '%s' had " + "enabled probes", ctl->mod_modname); +#else + cmn_err(CE_WARN, "unloaded module '%s' had " + "enabled probes", modname); +#endif + } + + return; + } + } + + probe = first; + + for (first = NULL; probe != NULL; probe = next) { + ASSERT(dtrace_probes[probe->dtpr_id - 1] == probe); + + dtrace_probes[probe->dtpr_id - 1] = NULL; + + next = probe->dtpr_nextmod; + dtrace_hash_remove(dtrace_bymod, probe); + dtrace_hash_remove(dtrace_byfunc, probe); + dtrace_hash_remove(dtrace_byname, probe); + + if (first == NULL) { + first = probe; + probe->dtpr_nextmod = NULL; + } else { + probe->dtpr_nextmod = first; + first = probe; + } + } + + /* + * We've removed all of the module's probes from the hash chains and + * from the probe array. Now issue a dtrace_sync() to be sure that + * everyone has cleared out from any probe array processing. + */ + dtrace_sync(); + + for (probe = first; probe != NULL; probe = first) { + first = probe->dtpr_nextmod; + prov = probe->dtpr_provider; + prov->dtpv_pops.dtps_destroy(prov->dtpv_arg, probe->dtpr_id, + probe->dtpr_arg); + kmem_free(probe->dtpr_mod, strlen(probe->dtpr_mod) + 1); + kmem_free(probe->dtpr_func, strlen(probe->dtpr_func) + 1); + kmem_free(probe->dtpr_name, strlen(probe->dtpr_name) + 1); +#ifdef illumos + vmem_free(dtrace_arena, (void *)(uintptr_t)probe->dtpr_id, 1); +#else + free_unr(dtrace_arena, probe->dtpr_id); +#endif + kmem_free(probe, sizeof (dtrace_probe_t)); + } + + mutex_exit(&dtrace_lock); +#ifdef illumos + mutex_exit(&mod_lock); +#endif + mutex_exit(&dtrace_provider_lock); +} + +#ifndef illumos +static void +dtrace_kld_load(void *arg __unused, linker_file_t lf) +{ + + dtrace_module_loaded(lf); +} + +static void +dtrace_kld_unload_try(void *arg __unused, linker_file_t lf, int *error) +{ + + if (*error != 0) + /* We already have an error, so don't do anything. */ + return; + dtrace_module_unloaded(lf, error); +} +#endif + +#ifdef illumos +static void +dtrace_suspend(void) +{ + dtrace_probe_foreach(offsetof(dtrace_pops_t, dtps_suspend)); +} + +static void +dtrace_resume(void) +{ + dtrace_probe_foreach(offsetof(dtrace_pops_t, dtps_resume)); +} +#endif + +static int +dtrace_cpu_setup(cpu_setup_t what, processorid_t cpu) +{ + ASSERT(MUTEX_HELD(&cpu_lock)); + mutex_enter(&dtrace_lock); + + switch (what) { + case CPU_CONFIG: { + dtrace_state_t *state; + dtrace_optval_t *opt, rs, c; + + /* + * For now, we only allocate a new buffer for anonymous state. + */ + if ((state = dtrace_anon.dta_state) == NULL) + break; + + if (state->dts_activity != DTRACE_ACTIVITY_ACTIVE) + break; + + opt = state->dts_options; + c = opt[DTRACEOPT_CPU]; + + if (c != DTRACE_CPUALL && c != DTRACEOPT_UNSET && c != cpu) + break; + + /* + * Regardless of what the actual policy is, we're going to + * temporarily set our resize policy to be manual. We're + * also going to temporarily set our CPU option to denote + * the newly configured CPU. + */ + rs = opt[DTRACEOPT_BUFRESIZE]; + opt[DTRACEOPT_BUFRESIZE] = DTRACEOPT_BUFRESIZE_MANUAL; + opt[DTRACEOPT_CPU] = (dtrace_optval_t)cpu; + + (void) dtrace_state_buffers(state); + + opt[DTRACEOPT_BUFRESIZE] = rs; + opt[DTRACEOPT_CPU] = c; + + break; + } + + case CPU_UNCONFIG: + /* + * We don't free the buffer in the CPU_UNCONFIG case. (The + * buffer will be freed when the consumer exits.) + */ + break; + + default: + break; + } + + mutex_exit(&dtrace_lock); + return (0); +} + +#ifdef illumos +static void +dtrace_cpu_setup_initial(processorid_t cpu) +{ + (void) dtrace_cpu_setup(CPU_CONFIG, cpu); +} +#endif + +static void +dtrace_toxrange_add(uintptr_t base, uintptr_t limit) +{ + if (dtrace_toxranges >= dtrace_toxranges_max) { + int osize, nsize; + dtrace_toxrange_t *range; + + osize = dtrace_toxranges_max * sizeof (dtrace_toxrange_t); + + if (osize == 0) { + ASSERT(dtrace_toxrange == NULL); + ASSERT(dtrace_toxranges_max == 0); + dtrace_toxranges_max = 1; + } else { + dtrace_toxranges_max <<= 1; + } + + nsize = dtrace_toxranges_max * sizeof (dtrace_toxrange_t); + range = kmem_zalloc(nsize, KM_SLEEP); + + if (dtrace_toxrange != NULL) { + ASSERT(osize != 0); + bcopy(dtrace_toxrange, range, osize); + kmem_free(dtrace_toxrange, osize); + } + + dtrace_toxrange = range; + } + + ASSERT(dtrace_toxrange[dtrace_toxranges].dtt_base == 0); + ASSERT(dtrace_toxrange[dtrace_toxranges].dtt_limit == 0); + + dtrace_toxrange[dtrace_toxranges].dtt_base = base; + dtrace_toxrange[dtrace_toxranges].dtt_limit = limit; + dtrace_toxranges++; +} + +static void +dtrace_getf_barrier() +{ +#ifdef illumos + /* + * When we have unprivileged (that is, non-DTRACE_CRV_KERNEL) enablings + * that contain calls to getf(), this routine will be called on every + * closef() before either the underlying vnode is released or the + * file_t itself is freed. By the time we are here, it is essential + * that the file_t can no longer be accessed from a call to getf() + * in probe context -- that assures that a dtrace_sync() can be used + * to clear out any enablings referring to the old structures. + */ + if (curthread->t_procp->p_zone->zone_dtrace_getf != 0 || + kcred->cr_zone->zone_dtrace_getf != 0) + dtrace_sync(); +#endif +} + +/* + * DTrace Driver Cookbook Functions + */ +#ifdef illumos +/*ARGSUSED*/ +static int +dtrace_attach(dev_info_t *devi, ddi_attach_cmd_t cmd) +{ + dtrace_provider_id_t id; + dtrace_state_t *state = NULL; + dtrace_enabling_t *enab; + + mutex_enter(&cpu_lock); + mutex_enter(&dtrace_provider_lock); + mutex_enter(&dtrace_lock); + + if (ddi_soft_state_init(&dtrace_softstate, + sizeof (dtrace_state_t), 0) != 0) { + cmn_err(CE_NOTE, "/dev/dtrace failed to initialize soft state"); + mutex_exit(&cpu_lock); + mutex_exit(&dtrace_provider_lock); + mutex_exit(&dtrace_lock); + return (DDI_FAILURE); + } + + if (ddi_create_minor_node(devi, DTRACEMNR_DTRACE, S_IFCHR, + DTRACEMNRN_DTRACE, DDI_PSEUDO, NULL) == DDI_FAILURE || + ddi_create_minor_node(devi, DTRACEMNR_HELPER, S_IFCHR, + DTRACEMNRN_HELPER, DDI_PSEUDO, NULL) == DDI_FAILURE) { + cmn_err(CE_NOTE, "/dev/dtrace couldn't create minor nodes"); + ddi_remove_minor_node(devi, NULL); + ddi_soft_state_fini(&dtrace_softstate); + mutex_exit(&cpu_lock); + mutex_exit(&dtrace_provider_lock); + mutex_exit(&dtrace_lock); + return (DDI_FAILURE); + } + + ddi_report_dev(devi); + dtrace_devi = devi; + + dtrace_modload = dtrace_module_loaded; + dtrace_modunload = dtrace_module_unloaded; + dtrace_cpu_init = dtrace_cpu_setup_initial; + dtrace_helpers_cleanup = dtrace_helpers_destroy; + dtrace_helpers_fork = dtrace_helpers_duplicate; + dtrace_cpustart_init = dtrace_suspend; + dtrace_cpustart_fini = dtrace_resume; + dtrace_debugger_init = dtrace_suspend; + dtrace_debugger_fini = dtrace_resume; + + register_cpu_setup_func((cpu_setup_func_t *)dtrace_cpu_setup, NULL); + + ASSERT(MUTEX_HELD(&cpu_lock)); + + dtrace_arena = vmem_create("dtrace", (void *)1, UINT32_MAX, 1, + NULL, NULL, NULL, 0, VM_SLEEP | VMC_IDENTIFIER); + dtrace_minor = vmem_create("dtrace_minor", (void *)DTRACEMNRN_CLONE, + UINT32_MAX - DTRACEMNRN_CLONE, 1, NULL, NULL, NULL, 0, + VM_SLEEP | VMC_IDENTIFIER); + dtrace_taskq = taskq_create("dtrace_taskq", 1, maxclsyspri, + 1, INT_MAX, 0); + + dtrace_state_cache = kmem_cache_create("dtrace_state_cache", + sizeof (dtrace_dstate_percpu_t) * NCPU, DTRACE_STATE_ALIGN, + NULL, NULL, NULL, NULL, NULL, 0); + + ASSERT(MUTEX_HELD(&cpu_lock)); + dtrace_bymod = dtrace_hash_create(offsetof(dtrace_probe_t, dtpr_mod), + offsetof(dtrace_probe_t, dtpr_nextmod), + offsetof(dtrace_probe_t, dtpr_prevmod)); + + dtrace_byfunc = dtrace_hash_create(offsetof(dtrace_probe_t, dtpr_func), + offsetof(dtrace_probe_t, dtpr_nextfunc), + offsetof(dtrace_probe_t, dtpr_prevfunc)); + + dtrace_byname = dtrace_hash_create(offsetof(dtrace_probe_t, dtpr_name), + offsetof(dtrace_probe_t, dtpr_nextname), + offsetof(dtrace_probe_t, dtpr_prevname)); + + if (dtrace_retain_max < 1) { + cmn_err(CE_WARN, "illegal value (%lu) for dtrace_retain_max; " + "setting to 1", dtrace_retain_max); + dtrace_retain_max = 1; + } + + /* + * Now discover our toxic ranges. + */ + dtrace_toxic_ranges(dtrace_toxrange_add); + + /* + * Before we register ourselves as a provider to our own framework, + * we would like to assert that dtrace_provider is NULL -- but that's + * not true if we were loaded as a dependency of a DTrace provider. + * Once we've registered, we can assert that dtrace_provider is our + * pseudo provider. + */ + (void) dtrace_register("dtrace", &dtrace_provider_attr, + DTRACE_PRIV_NONE, 0, &dtrace_provider_ops, NULL, &id); + + ASSERT(dtrace_provider != NULL); + ASSERT((dtrace_provider_id_t)dtrace_provider == id); + + dtrace_probeid_begin = dtrace_probe_create((dtrace_provider_id_t) + dtrace_provider, NULL, NULL, "BEGIN", 0, NULL); + dtrace_probeid_end = dtrace_probe_create((dtrace_provider_id_t) + dtrace_provider, NULL, NULL, "END", 0, NULL); + dtrace_probeid_error = dtrace_probe_create((dtrace_provider_id_t) + dtrace_provider, NULL, NULL, "ERROR", 1, NULL); + + dtrace_anon_property(); + mutex_exit(&cpu_lock); + + /* + * If there are already providers, we must ask them to provide their + * probes, and then match any anonymous enabling against them. Note + * that there should be no other retained enablings at this time: + * the only retained enablings at this time should be the anonymous + * enabling. + */ + if (dtrace_anon.dta_enabling != NULL) { + ASSERT(dtrace_retained == dtrace_anon.dta_enabling); + + dtrace_enabling_provide(NULL); + state = dtrace_anon.dta_state; + + /* + * We couldn't hold cpu_lock across the above call to + * dtrace_enabling_provide(), but we must hold it to actually + * enable the probes. We have to drop all of our locks, pick + * up cpu_lock, and regain our locks before matching the + * retained anonymous enabling. + */ + mutex_exit(&dtrace_lock); + mutex_exit(&dtrace_provider_lock); + + mutex_enter(&cpu_lock); + mutex_enter(&dtrace_provider_lock); + mutex_enter(&dtrace_lock); + + if ((enab = dtrace_anon.dta_enabling) != NULL) + (void) dtrace_enabling_match(enab, NULL); + + mutex_exit(&cpu_lock); + } + + mutex_exit(&dtrace_lock); + mutex_exit(&dtrace_provider_lock); + + if (state != NULL) { + /* + * If we created any anonymous state, set it going now. + */ + (void) dtrace_state_go(state, &dtrace_anon.dta_beganon); + } + + return (DDI_SUCCESS); +} +#endif /* illumos */ + +#ifndef illumos +static void dtrace_dtr(void *); +#endif + +/*ARGSUSED*/ +static int +#ifdef illumos +dtrace_open(dev_t *devp, int flag, int otyp, cred_t *cred_p) +#else +dtrace_open(struct cdev *dev, int oflags, int devtype, struct thread *td) +#endif +{ + dtrace_state_t *state; + uint32_t priv; + uid_t uid; + zoneid_t zoneid; + +#ifdef illumos + if (getminor(*devp) == DTRACEMNRN_HELPER) + return (0); + + /* + * If this wasn't an open with the "helper" minor, then it must be + * the "dtrace" minor. + */ + if (getminor(*devp) == DTRACEMNRN_DTRACE) + return (ENXIO); +#else + cred_t *cred_p = NULL; + cred_p = dev->si_cred; + + /* + * If no DTRACE_PRIV_* bits are set in the credential, then the + * caller lacks sufficient permission to do anything with DTrace. + */ + dtrace_cred2priv(cred_p, &priv, &uid, &zoneid); + if (priv == DTRACE_PRIV_NONE) { +#endif + + return (EACCES); + } + + /* + * Ask all providers to provide all their probes. + */ + mutex_enter(&dtrace_provider_lock); + dtrace_probe_provide(NULL, NULL); + mutex_exit(&dtrace_provider_lock); + + mutex_enter(&cpu_lock); + mutex_enter(&dtrace_lock); + dtrace_opens++; + dtrace_membar_producer(); + +#ifdef illumos + /* + * If the kernel debugger is active (that is, if the kernel debugger + * modified text in some way), we won't allow the open. + */ + if (kdi_dtrace_set(KDI_DTSET_DTRACE_ACTIVATE) != 0) { + dtrace_opens--; + mutex_exit(&cpu_lock); + mutex_exit(&dtrace_lock); + return (EBUSY); + } + + if (dtrace_helptrace_enable && dtrace_helptrace_buffer == NULL) { + /* + * If DTrace helper tracing is enabled, we need to allocate the + * trace buffer and initialize the values. + */ + dtrace_helptrace_buffer = + kmem_zalloc(dtrace_helptrace_bufsize, KM_SLEEP); + dtrace_helptrace_next = 0; + dtrace_helptrace_wrapped = 0; + dtrace_helptrace_enable = 0; + } + + state = dtrace_state_create(devp, cred_p); +#else + state = dtrace_state_create(dev, NULL); + devfs_set_cdevpriv(state, dtrace_dtr); +#endif + + mutex_exit(&cpu_lock); + + if (state == NULL) { +#ifdef illumos + if (--dtrace_opens == 0 && dtrace_anon.dta_enabling == NULL) + (void) kdi_dtrace_set(KDI_DTSET_DTRACE_DEACTIVATE); +#else + --dtrace_opens; +#endif + mutex_exit(&dtrace_lock); + return (EAGAIN); + } + + mutex_exit(&dtrace_lock); + + return (0); +} + +/*ARGSUSED*/ +#ifdef illumos +static int +dtrace_close(dev_t dev, int flag, int otyp, cred_t *cred_p) +#else +static void +dtrace_dtr(void *data) +#endif +{ +#ifdef illumos + minor_t minor = getminor(dev); + dtrace_state_t *state; +#endif + dtrace_helptrace_t *buf = NULL; + +#ifdef illumos + if (minor == DTRACEMNRN_HELPER) + return (0); + + state = ddi_get_soft_state(dtrace_softstate, minor); +#else + dtrace_state_t *state = data; +#endif + + mutex_enter(&cpu_lock); + mutex_enter(&dtrace_lock); + +#ifdef illumos + if (state->dts_anon) +#else + if (state != NULL && state->dts_anon) +#endif + { + /* + * There is anonymous state. Destroy that first. + */ + ASSERT(dtrace_anon.dta_state == NULL); + dtrace_state_destroy(state->dts_anon); + } + + if (dtrace_helptrace_disable) { + /* + * If we have been told to disable helper tracing, set the + * buffer to NULL before calling into dtrace_state_destroy(); + * we take advantage of its dtrace_sync() to know that no + * CPU is in probe context with enabled helper tracing + * after it returns. + */ + buf = dtrace_helptrace_buffer; + dtrace_helptrace_buffer = NULL; + } + +#ifdef illumos + dtrace_state_destroy(state); +#else + if (state != NULL) { + dtrace_state_destroy(state); + kmem_free(state, 0); + } +#endif + ASSERT(dtrace_opens > 0); + +#ifdef illumos + /* + * Only relinquish control of the kernel debugger interface when there + * are no consumers and no anonymous enablings. + */ + if (--dtrace_opens == 0 && dtrace_anon.dta_enabling == NULL) + (void) kdi_dtrace_set(KDI_DTSET_DTRACE_DEACTIVATE); +#else + --dtrace_opens; +#endif + + if (buf != NULL) { + kmem_free(buf, dtrace_helptrace_bufsize); + dtrace_helptrace_disable = 0; + } + + mutex_exit(&dtrace_lock); + mutex_exit(&cpu_lock); + +#ifdef illumos + return (0); +#endif +} + +#ifdef illumos +/*ARGSUSED*/ +static int +dtrace_ioctl_helper(int cmd, intptr_t arg, int *rv) +{ + int rval; + dof_helper_t help, *dhp = NULL; + + switch (cmd) { + case DTRACEHIOC_ADDDOF: + if (copyin((void *)arg, &help, sizeof (help)) != 0) { + dtrace_dof_error(NULL, "failed to copyin DOF helper"); + return (EFAULT); + } + + dhp = &help; + arg = (intptr_t)help.dofhp_dof; + /*FALLTHROUGH*/ + + case DTRACEHIOC_ADD: { + dof_hdr_t *dof = dtrace_dof_copyin(arg, &rval); + + if (dof == NULL) + return (rval); + + mutex_enter(&dtrace_lock); + + /* + * dtrace_helper_slurp() takes responsibility for the dof -- + * it may free it now or it may save it and free it later. + */ + if ((rval = dtrace_helper_slurp(dof, dhp)) != -1) { + *rv = rval; + rval = 0; + } else { + rval = EINVAL; + } + + mutex_exit(&dtrace_lock); + return (rval); + } + + case DTRACEHIOC_REMOVE: { + mutex_enter(&dtrace_lock); + rval = dtrace_helper_destroygen(NULL, arg); + mutex_exit(&dtrace_lock); + + return (rval); + } + + default: + break; + } + + return (ENOTTY); +} + +/*ARGSUSED*/ +static int +dtrace_ioctl(dev_t dev, int cmd, intptr_t arg, int md, cred_t *cr, int *rv) +{ + minor_t minor = getminor(dev); + dtrace_state_t *state; + int rval; + + if (minor == DTRACEMNRN_HELPER) + return (dtrace_ioctl_helper(cmd, arg, rv)); + + state = ddi_get_soft_state(dtrace_softstate, minor); + + if (state->dts_anon) { + ASSERT(dtrace_anon.dta_state == NULL); + state = state->dts_anon; + } + + switch (cmd) { + case DTRACEIOC_PROVIDER: { + dtrace_providerdesc_t pvd; + dtrace_provider_t *pvp; + + if (copyin((void *)arg, &pvd, sizeof (pvd)) != 0) + return (EFAULT); + + pvd.dtvd_name[DTRACE_PROVNAMELEN - 1] = '\0'; + mutex_enter(&dtrace_provider_lock); + + for (pvp = dtrace_provider; pvp != NULL; pvp = pvp->dtpv_next) { + if (strcmp(pvp->dtpv_name, pvd.dtvd_name) == 0) + break; + } + + mutex_exit(&dtrace_provider_lock); + + if (pvp == NULL) + return (ESRCH); + + bcopy(&pvp->dtpv_priv, &pvd.dtvd_priv, sizeof (dtrace_ppriv_t)); + bcopy(&pvp->dtpv_attr, &pvd.dtvd_attr, sizeof (dtrace_pattr_t)); + + if (copyout(&pvd, (void *)arg, sizeof (pvd)) != 0) + return (EFAULT); + + return (0); + } + + case DTRACEIOC_EPROBE: { + dtrace_eprobedesc_t epdesc; + dtrace_ecb_t *ecb; + dtrace_action_t *act; + void *buf; + size_t size; + uintptr_t dest; + int nrecs; + + if (copyin((void *)arg, &epdesc, sizeof (epdesc)) != 0) + return (EFAULT); + + mutex_enter(&dtrace_lock); + + if ((ecb = dtrace_epid2ecb(state, epdesc.dtepd_epid)) == NULL) { + mutex_exit(&dtrace_lock); + return (EINVAL); + } + + if (ecb->dte_probe == NULL) { + mutex_exit(&dtrace_lock); + return (EINVAL); + } + + epdesc.dtepd_probeid = ecb->dte_probe->dtpr_id; + epdesc.dtepd_uarg = ecb->dte_uarg; + epdesc.dtepd_size = ecb->dte_size; + + nrecs = epdesc.dtepd_nrecs; + epdesc.dtepd_nrecs = 0; + for (act = ecb->dte_action; act != NULL; act = act->dta_next) { + if (DTRACEACT_ISAGG(act->dta_kind) || act->dta_intuple) + continue; + + epdesc.dtepd_nrecs++; + } + + /* + * Now that we have the size, we need to allocate a temporary + * buffer in which to store the complete description. We need + * the temporary buffer to be able to drop dtrace_lock() + * across the copyout(), below. + */ + size = sizeof (dtrace_eprobedesc_t) + + (epdesc.dtepd_nrecs * sizeof (dtrace_recdesc_t)); + + buf = kmem_alloc(size, KM_SLEEP); + dest = (uintptr_t)buf; + + bcopy(&epdesc, (void *)dest, sizeof (epdesc)); + dest += offsetof(dtrace_eprobedesc_t, dtepd_rec[0]); + + for (act = ecb->dte_action; act != NULL; act = act->dta_next) { + if (DTRACEACT_ISAGG(act->dta_kind) || act->dta_intuple) + continue; + + if (nrecs-- == 0) + break; + + bcopy(&act->dta_rec, (void *)dest, + sizeof (dtrace_recdesc_t)); + dest += sizeof (dtrace_recdesc_t); + } + + mutex_exit(&dtrace_lock); + + if (copyout(buf, (void *)arg, dest - (uintptr_t)buf) != 0) { + kmem_free(buf, size); + return (EFAULT); + } + + kmem_free(buf, size); + return (0); + } + + case DTRACEIOC_AGGDESC: { + dtrace_aggdesc_t aggdesc; + dtrace_action_t *act; + dtrace_aggregation_t *agg; + int nrecs; + uint32_t offs; + dtrace_recdesc_t *lrec; + void *buf; + size_t size; + uintptr_t dest; + + if (copyin((void *)arg, &aggdesc, sizeof (aggdesc)) != 0) + return (EFAULT); + + mutex_enter(&dtrace_lock); + + if ((agg = dtrace_aggid2agg(state, aggdesc.dtagd_id)) == NULL) { + mutex_exit(&dtrace_lock); + return (EINVAL); + } + + aggdesc.dtagd_epid = agg->dtag_ecb->dte_epid; + + nrecs = aggdesc.dtagd_nrecs; + aggdesc.dtagd_nrecs = 0; + + offs = agg->dtag_base; + lrec = &agg->dtag_action.dta_rec; + aggdesc.dtagd_size = lrec->dtrd_offset + lrec->dtrd_size - offs; + + for (act = agg->dtag_first; ; act = act->dta_next) { + ASSERT(act->dta_intuple || + DTRACEACT_ISAGG(act->dta_kind)); + + /* + * If this action has a record size of zero, it + * denotes an argument to the aggregating action. + * Because the presence of this record doesn't (or + * shouldn't) affect the way the data is interpreted, + * we don't copy it out to save user-level the + * confusion of dealing with a zero-length record. + */ + if (act->dta_rec.dtrd_size == 0) { + ASSERT(agg->dtag_hasarg); + continue; + } + + aggdesc.dtagd_nrecs++; + + if (act == &agg->dtag_action) + break; + } + + /* + * Now that we have the size, we need to allocate a temporary + * buffer in which to store the complete description. We need + * the temporary buffer to be able to drop dtrace_lock() + * across the copyout(), below. + */ + size = sizeof (dtrace_aggdesc_t) + + (aggdesc.dtagd_nrecs * sizeof (dtrace_recdesc_t)); + + buf = kmem_alloc(size, KM_SLEEP); + dest = (uintptr_t)buf; + + bcopy(&aggdesc, (void *)dest, sizeof (aggdesc)); + dest += offsetof(dtrace_aggdesc_t, dtagd_rec[0]); + + for (act = agg->dtag_first; ; act = act->dta_next) { + dtrace_recdesc_t rec = act->dta_rec; + + /* + * See the comment in the above loop for why we pass + * over zero-length records. + */ + if (rec.dtrd_size == 0) { + ASSERT(agg->dtag_hasarg); + continue; + } + + if (nrecs-- == 0) + break; + + rec.dtrd_offset -= offs; + bcopy(&rec, (void *)dest, sizeof (rec)); + dest += sizeof (dtrace_recdesc_t); + + if (act == &agg->dtag_action) + break; + } + + mutex_exit(&dtrace_lock); + + if (copyout(buf, (void *)arg, dest - (uintptr_t)buf) != 0) { + kmem_free(buf, size); + return (EFAULT); + } + + kmem_free(buf, size); + return (0); + } + + case DTRACEIOC_ENABLE: { + dof_hdr_t *dof; + dtrace_enabling_t *enab = NULL; + dtrace_vstate_t *vstate; + int err = 0; + + *rv = 0; + + /* + * If a NULL argument has been passed, we take this as our + * cue to reevaluate our enablings. + */ + if (arg == NULL) { + dtrace_enabling_matchall(); + + return (0); + } + + if ((dof = dtrace_dof_copyin(arg, &rval)) == NULL) + return (rval); + + mutex_enter(&cpu_lock); + mutex_enter(&dtrace_lock); + vstate = &state->dts_vstate; + + if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE) { + mutex_exit(&dtrace_lock); + mutex_exit(&cpu_lock); + dtrace_dof_destroy(dof); + return (EBUSY); + } + + if (dtrace_dof_slurp(dof, vstate, cr, &enab, 0, B_TRUE) != 0) { + mutex_exit(&dtrace_lock); + mutex_exit(&cpu_lock); + dtrace_dof_destroy(dof); + return (EINVAL); + } + + if ((rval = dtrace_dof_options(dof, state)) != 0) { + dtrace_enabling_destroy(enab); + mutex_exit(&dtrace_lock); + mutex_exit(&cpu_lock); + dtrace_dof_destroy(dof); + return (rval); + } + + if ((err = dtrace_enabling_match(enab, rv)) == 0) { + err = dtrace_enabling_retain(enab); + } else { + dtrace_enabling_destroy(enab); + } + + mutex_exit(&cpu_lock); + mutex_exit(&dtrace_lock); + dtrace_dof_destroy(dof); + + return (err); + } + + case DTRACEIOC_REPLICATE: { + dtrace_repldesc_t desc; + dtrace_probedesc_t *match = &desc.dtrpd_match; + dtrace_probedesc_t *create = &desc.dtrpd_create; + int err; + + if (copyin((void *)arg, &desc, sizeof (desc)) != 0) + return (EFAULT); + + match->dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0'; + match->dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0'; + match->dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0'; + match->dtpd_name[DTRACE_NAMELEN - 1] = '\0'; + + create->dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0'; + create->dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0'; + create->dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0'; + create->dtpd_name[DTRACE_NAMELEN - 1] = '\0'; + + mutex_enter(&dtrace_lock); + err = dtrace_enabling_replicate(state, match, create); + mutex_exit(&dtrace_lock); + + return (err); + } + + case DTRACEIOC_PROBEMATCH: + case DTRACEIOC_PROBES: { + dtrace_probe_t *probe = NULL; + dtrace_probedesc_t desc; + dtrace_probekey_t pkey; + dtrace_id_t i; + int m = 0; + uint32_t priv; + uid_t uid; + zoneid_t zoneid; + + if (copyin((void *)arg, &desc, sizeof (desc)) != 0) + return (EFAULT); + + desc.dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0'; + desc.dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0'; + desc.dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0'; + desc.dtpd_name[DTRACE_NAMELEN - 1] = '\0'; + + /* + * Before we attempt to match this probe, we want to give + * all providers the opportunity to provide it. + */ + if (desc.dtpd_id == DTRACE_IDNONE) { + mutex_enter(&dtrace_provider_lock); + dtrace_probe_provide(&desc, NULL); + mutex_exit(&dtrace_provider_lock); + desc.dtpd_id++; + } + + if (cmd == DTRACEIOC_PROBEMATCH) { + dtrace_probekey(&desc, &pkey); + pkey.dtpk_id = DTRACE_IDNONE; + } + + dtrace_cred2priv(cr, &priv, &uid, &zoneid); + + mutex_enter(&dtrace_lock); + + if (cmd == DTRACEIOC_PROBEMATCH) { + for (i = desc.dtpd_id; i <= dtrace_nprobes; i++) { + if ((probe = dtrace_probes[i - 1]) != NULL && + (m = dtrace_match_probe(probe, &pkey, + priv, uid, zoneid)) != 0) + break; + } + + if (m < 0) { + mutex_exit(&dtrace_lock); + return (EINVAL); + } + + } else { + for (i = desc.dtpd_id; i <= dtrace_nprobes; i++) { + if ((probe = dtrace_probes[i - 1]) != NULL && + dtrace_match_priv(probe, priv, uid, zoneid)) + break; + } + } + + if (probe == NULL) { + mutex_exit(&dtrace_lock); + return (ESRCH); + } + + dtrace_probe_description(probe, &desc); + mutex_exit(&dtrace_lock); + + if (copyout(&desc, (void *)arg, sizeof (desc)) != 0) + return (EFAULT); + + return (0); + } + + case DTRACEIOC_PROBEARG: { + dtrace_argdesc_t desc; + dtrace_probe_t *probe; + dtrace_provider_t *prov; + + if (copyin((void *)arg, &desc, sizeof (desc)) != 0) + return (EFAULT); + + if (desc.dtargd_id == DTRACE_IDNONE) + return (EINVAL); + + if (desc.dtargd_ndx == DTRACE_ARGNONE) + return (EINVAL); + + mutex_enter(&dtrace_provider_lock); + mutex_enter(&mod_lock); + mutex_enter(&dtrace_lock); + + if (desc.dtargd_id > dtrace_nprobes) { + mutex_exit(&dtrace_lock); + mutex_exit(&mod_lock); + mutex_exit(&dtrace_provider_lock); + return (EINVAL); + } + + if ((probe = dtrace_probes[desc.dtargd_id - 1]) == NULL) { + mutex_exit(&dtrace_lock); + mutex_exit(&mod_lock); + mutex_exit(&dtrace_provider_lock); + return (EINVAL); + } + + mutex_exit(&dtrace_lock); + + prov = probe->dtpr_provider; + + if (prov->dtpv_pops.dtps_getargdesc == NULL) { + /* + * There isn't any typed information for this probe. + * Set the argument number to DTRACE_ARGNONE. + */ + desc.dtargd_ndx = DTRACE_ARGNONE; + } else { + desc.dtargd_native[0] = '\0'; + desc.dtargd_xlate[0] = '\0'; + desc.dtargd_mapping = desc.dtargd_ndx; + + prov->dtpv_pops.dtps_getargdesc(prov->dtpv_arg, + probe->dtpr_id, probe->dtpr_arg, &desc); + } + + mutex_exit(&mod_lock); + mutex_exit(&dtrace_provider_lock); + + if (copyout(&desc, (void *)arg, sizeof (desc)) != 0) + return (EFAULT); + + return (0); + } + + case DTRACEIOC_GO: { + processorid_t cpuid; + rval = dtrace_state_go(state, &cpuid); + + if (rval != 0) + return (rval); + + if (copyout(&cpuid, (void *)arg, sizeof (cpuid)) != 0) + return (EFAULT); + + return (0); + } + + case DTRACEIOC_STOP: { + processorid_t cpuid; + + mutex_enter(&dtrace_lock); + rval = dtrace_state_stop(state, &cpuid); + mutex_exit(&dtrace_lock); + + if (rval != 0) + return (rval); + + if (copyout(&cpuid, (void *)arg, sizeof (cpuid)) != 0) + return (EFAULT); + + return (0); + } + + case DTRACEIOC_DOFGET: { + dof_hdr_t hdr, *dof; + uint64_t len; + + if (copyin((void *)arg, &hdr, sizeof (hdr)) != 0) + return (EFAULT); + + mutex_enter(&dtrace_lock); + dof = dtrace_dof_create(state); + mutex_exit(&dtrace_lock); + + len = MIN(hdr.dofh_loadsz, dof->dofh_loadsz); + rval = copyout(dof, (void *)arg, len); + dtrace_dof_destroy(dof); + + return (rval == 0 ? 0 : EFAULT); + } + + case DTRACEIOC_AGGSNAP: + case DTRACEIOC_BUFSNAP: { + dtrace_bufdesc_t desc; + caddr_t cached; + dtrace_buffer_t *buf; + + if (copyin((void *)arg, &desc, sizeof (desc)) != 0) + return (EFAULT); + + if (desc.dtbd_cpu < 0 || desc.dtbd_cpu >= NCPU) + return (EINVAL); + + mutex_enter(&dtrace_lock); + + if (cmd == DTRACEIOC_BUFSNAP) { + buf = &state->dts_buffer[desc.dtbd_cpu]; + } else { + buf = &state->dts_aggbuffer[desc.dtbd_cpu]; + } + + if (buf->dtb_flags & (DTRACEBUF_RING | DTRACEBUF_FILL)) { + size_t sz = buf->dtb_offset; + + if (state->dts_activity != DTRACE_ACTIVITY_STOPPED) { + mutex_exit(&dtrace_lock); + return (EBUSY); + } + + /* + * If this buffer has already been consumed, we're + * going to indicate that there's nothing left here + * to consume. + */ + if (buf->dtb_flags & DTRACEBUF_CONSUMED) { + mutex_exit(&dtrace_lock); + + desc.dtbd_size = 0; + desc.dtbd_drops = 0; + desc.dtbd_errors = 0; + desc.dtbd_oldest = 0; + sz = sizeof (desc); + + if (copyout(&desc, (void *)arg, sz) != 0) + return (EFAULT); + + return (0); + } + + /* + * If this is a ring buffer that has wrapped, we want + * to copy the whole thing out. + */ + if (buf->dtb_flags & DTRACEBUF_WRAPPED) { + dtrace_buffer_polish(buf); + sz = buf->dtb_size; + } + + if (copyout(buf->dtb_tomax, desc.dtbd_data, sz) != 0) { + mutex_exit(&dtrace_lock); + return (EFAULT); + } + + desc.dtbd_size = sz; + desc.dtbd_drops = buf->dtb_drops; + desc.dtbd_errors = buf->dtb_errors; + desc.dtbd_oldest = buf->dtb_xamot_offset; + desc.dtbd_timestamp = dtrace_gethrtime(); + + mutex_exit(&dtrace_lock); + + if (copyout(&desc, (void *)arg, sizeof (desc)) != 0) + return (EFAULT); + + buf->dtb_flags |= DTRACEBUF_CONSUMED; + + return (0); + } + + if (buf->dtb_tomax == NULL) { + ASSERT(buf->dtb_xamot == NULL); + mutex_exit(&dtrace_lock); + return (ENOENT); + } + + cached = buf->dtb_tomax; + ASSERT(!(buf->dtb_flags & DTRACEBUF_NOSWITCH)); + + dtrace_xcall(desc.dtbd_cpu, + (dtrace_xcall_t)dtrace_buffer_switch, buf); + + state->dts_errors += buf->dtb_xamot_errors; + + /* + * If the buffers did not actually switch, then the cross call + * did not take place -- presumably because the given CPU is + * not in the ready set. If this is the case, we'll return + * ENOENT. + */ + if (buf->dtb_tomax == cached) { + ASSERT(buf->dtb_xamot != cached); + mutex_exit(&dtrace_lock); + return (ENOENT); + } + + ASSERT(cached == buf->dtb_xamot); + + /* + * We have our snapshot; now copy it out. + */ + if (copyout(buf->dtb_xamot, desc.dtbd_data, + buf->dtb_xamot_offset) != 0) { + mutex_exit(&dtrace_lock); + return (EFAULT); + } + + desc.dtbd_size = buf->dtb_xamot_offset; + desc.dtbd_drops = buf->dtb_xamot_drops; + desc.dtbd_errors = buf->dtb_xamot_errors; + desc.dtbd_oldest = 0; + desc.dtbd_timestamp = buf->dtb_switched; + + mutex_exit(&dtrace_lock); + + /* + * Finally, copy out the buffer description. + */ + if (copyout(&desc, (void *)arg, sizeof (desc)) != 0) + return (EFAULT); + + return (0); + } + + case DTRACEIOC_CONF: { + dtrace_conf_t conf; + + bzero(&conf, sizeof (conf)); + conf.dtc_difversion = DIF_VERSION; + conf.dtc_difintregs = DIF_DIR_NREGS; + conf.dtc_diftupregs = DIF_DTR_NREGS; + conf.dtc_ctfmodel = CTF_MODEL_NATIVE; + + if (copyout(&conf, (void *)arg, sizeof (conf)) != 0) + return (EFAULT); + + return (0); + } + + case DTRACEIOC_STATUS: { + dtrace_status_t stat; + dtrace_dstate_t *dstate; + int i, j; + uint64_t nerrs; + + /* + * See the comment in dtrace_state_deadman() for the reason + * for setting dts_laststatus to INT64_MAX before setting + * it to the correct value. + */ + state->dts_laststatus = INT64_MAX; + dtrace_membar_producer(); + state->dts_laststatus = dtrace_gethrtime(); + + bzero(&stat, sizeof (stat)); + + mutex_enter(&dtrace_lock); + + if (state->dts_activity == DTRACE_ACTIVITY_INACTIVE) { + mutex_exit(&dtrace_lock); + return (ENOENT); + } + + if (state->dts_activity == DTRACE_ACTIVITY_DRAINING) + stat.dtst_exiting = 1; + + nerrs = state->dts_errors; + dstate = &state->dts_vstate.dtvs_dynvars; + + for (i = 0; i < NCPU; i++) { + dtrace_dstate_percpu_t *dcpu = &dstate->dtds_percpu[i]; + + stat.dtst_dyndrops += dcpu->dtdsc_drops; + stat.dtst_dyndrops_dirty += dcpu->dtdsc_dirty_drops; + stat.dtst_dyndrops_rinsing += dcpu->dtdsc_rinsing_drops; + + if (state->dts_buffer[i].dtb_flags & DTRACEBUF_FULL) + stat.dtst_filled++; + + nerrs += state->dts_buffer[i].dtb_errors; + + for (j = 0; j < state->dts_nspeculations; j++) { + dtrace_speculation_t *spec; + dtrace_buffer_t *buf; + + spec = &state->dts_speculations[j]; + buf = &spec->dtsp_buffer[i]; + stat.dtst_specdrops += buf->dtb_xamot_drops; + } + } + + stat.dtst_specdrops_busy = state->dts_speculations_busy; + stat.dtst_specdrops_unavail = state->dts_speculations_unavail; + stat.dtst_stkstroverflows = state->dts_stkstroverflows; + stat.dtst_dblerrors = state->dts_dblerrors; + stat.dtst_killed = + (state->dts_activity == DTRACE_ACTIVITY_KILLED); + stat.dtst_errors = nerrs; + + mutex_exit(&dtrace_lock); + + if (copyout(&stat, (void *)arg, sizeof (stat)) != 0) + return (EFAULT); + + return (0); + } + + case DTRACEIOC_FORMAT: { + dtrace_fmtdesc_t fmt; + char *str; + int len; + + if (copyin((void *)arg, &fmt, sizeof (fmt)) != 0) + return (EFAULT); + + mutex_enter(&dtrace_lock); + + if (fmt.dtfd_format == 0 || + fmt.dtfd_format > state->dts_nformats) { + mutex_exit(&dtrace_lock); + return (EINVAL); + } + + /* + * Format strings are allocated contiguously and they are + * never freed; if a format index is less than the number + * of formats, we can assert that the format map is non-NULL + * and that the format for the specified index is non-NULL. + */ + ASSERT(state->dts_formats != NULL); + str = state->dts_formats[fmt.dtfd_format - 1]; + ASSERT(str != NULL); + + len = strlen(str) + 1; + + if (len > fmt.dtfd_length) { + fmt.dtfd_length = len; + + if (copyout(&fmt, (void *)arg, sizeof (fmt)) != 0) { + mutex_exit(&dtrace_lock); + return (EINVAL); + } + } else { + if (copyout(str, fmt.dtfd_string, len) != 0) { + mutex_exit(&dtrace_lock); + return (EINVAL); + } + } + + mutex_exit(&dtrace_lock); + return (0); + } + + default: + break; + } + + return (ENOTTY); +} + +/*ARGSUSED*/ +static int +dtrace_detach(dev_info_t *dip, ddi_detach_cmd_t cmd) +{ + dtrace_state_t *state; + + switch (cmd) { + case DDI_DETACH: + break; + + case DDI_SUSPEND: + return (DDI_SUCCESS); + + default: + return (DDI_FAILURE); + } + + mutex_enter(&cpu_lock); + mutex_enter(&dtrace_provider_lock); + mutex_enter(&dtrace_lock); + + ASSERT(dtrace_opens == 0); + + if (dtrace_helpers > 0) { + mutex_exit(&dtrace_provider_lock); + mutex_exit(&dtrace_lock); + mutex_exit(&cpu_lock); + return (DDI_FAILURE); + } + + if (dtrace_unregister((dtrace_provider_id_t)dtrace_provider) != 0) { + mutex_exit(&dtrace_provider_lock); + mutex_exit(&dtrace_lock); + mutex_exit(&cpu_lock); + return (DDI_FAILURE); + } + + dtrace_provider = NULL; + + if ((state = dtrace_anon_grab()) != NULL) { + /* + * If there were ECBs on this state, the provider should + * have not been allowed to detach; assert that there is + * none. + */ + ASSERT(state->dts_necbs == 0); + dtrace_state_destroy(state); + + /* + * If we're being detached with anonymous state, we need to + * indicate to the kernel debugger that DTrace is now inactive. + */ + (void) kdi_dtrace_set(KDI_DTSET_DTRACE_DEACTIVATE); + } + + bzero(&dtrace_anon, sizeof (dtrace_anon_t)); + unregister_cpu_setup_func((cpu_setup_func_t *)dtrace_cpu_setup, NULL); + dtrace_cpu_init = NULL; + dtrace_helpers_cleanup = NULL; + dtrace_helpers_fork = NULL; + dtrace_cpustart_init = NULL; + dtrace_cpustart_fini = NULL; + dtrace_debugger_init = NULL; + dtrace_debugger_fini = NULL; + dtrace_modload = NULL; + dtrace_modunload = NULL; + + ASSERT(dtrace_getf == 0); + ASSERT(dtrace_closef == NULL); + + mutex_exit(&cpu_lock); + + kmem_free(dtrace_probes, dtrace_nprobes * sizeof (dtrace_probe_t *)); + dtrace_probes = NULL; + dtrace_nprobes = 0; + + dtrace_hash_destroy(dtrace_bymod); + dtrace_hash_destroy(dtrace_byfunc); + dtrace_hash_destroy(dtrace_byname); + dtrace_bymod = NULL; + dtrace_byfunc = NULL; + dtrace_byname = NULL; + + kmem_cache_destroy(dtrace_state_cache); + vmem_destroy(dtrace_minor); + vmem_destroy(dtrace_arena); + + if (dtrace_toxrange != NULL) { + kmem_free(dtrace_toxrange, + dtrace_toxranges_max * sizeof (dtrace_toxrange_t)); + dtrace_toxrange = NULL; + dtrace_toxranges = 0; + dtrace_toxranges_max = 0; + } + + ddi_remove_minor_node(dtrace_devi, NULL); + dtrace_devi = NULL; + + ddi_soft_state_fini(&dtrace_softstate); + + ASSERT(dtrace_vtime_references == 0); + ASSERT(dtrace_opens == 0); + ASSERT(dtrace_retained == NULL); + + mutex_exit(&dtrace_lock); + mutex_exit(&dtrace_provider_lock); + + /* + * We don't destroy the task queue until after we have dropped our + * locks (taskq_destroy() may block on running tasks). To prevent + * attempting to do work after we have effectively detached but before + * the task queue has been destroyed, all tasks dispatched via the + * task queue must check that DTrace is still attached before + * performing any operation. + */ + taskq_destroy(dtrace_taskq); + dtrace_taskq = NULL; + + return (DDI_SUCCESS); +} +#endif + +#ifdef illumos +/*ARGSUSED*/ +static int +dtrace_info(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, void **result) +{ + int error; + + switch (infocmd) { + case DDI_INFO_DEVT2DEVINFO: + *result = (void *)dtrace_devi; + error = DDI_SUCCESS; + break; + case DDI_INFO_DEVT2INSTANCE: + *result = (void *)0; + error = DDI_SUCCESS; + break; + default: + error = DDI_FAILURE; + } + return (error); +} +#endif + +#ifdef illumos +static struct cb_ops dtrace_cb_ops = { + dtrace_open, /* open */ + dtrace_close, /* close */ + nulldev, /* strategy */ + nulldev, /* print */ + nodev, /* dump */ + nodev, /* read */ + nodev, /* write */ + dtrace_ioctl, /* ioctl */ + nodev, /* devmap */ + nodev, /* mmap */ + nodev, /* segmap */ + nochpoll, /* poll */ + ddi_prop_op, /* cb_prop_op */ + 0, /* streamtab */ + D_NEW | D_MP /* Driver compatibility flag */ +}; + +static struct dev_ops dtrace_ops = { + DEVO_REV, /* devo_rev */ + 0, /* refcnt */ + dtrace_info, /* get_dev_info */ + nulldev, /* identify */ + nulldev, /* probe */ + dtrace_attach, /* attach */ + dtrace_detach, /* detach */ + nodev, /* reset */ + &dtrace_cb_ops, /* driver operations */ + NULL, /* bus operations */ + nodev /* dev power */ +}; + +static struct modldrv modldrv = { + &mod_driverops, /* module type (this is a pseudo driver) */ + "Dynamic Tracing", /* name of module */ + &dtrace_ops, /* driver ops */ +}; + +static struct modlinkage modlinkage = { + MODREV_1, + (void *)&modldrv, + NULL +}; + +int +_init(void) +{ + return (mod_install(&modlinkage)); +} + +int +_info(struct modinfo *modinfop) +{ + return (mod_info(&modlinkage, modinfop)); +} + +int +_fini(void) +{ + return (mod_remove(&modlinkage)); +} +#else + +static d_ioctl_t dtrace_ioctl; +static d_ioctl_t dtrace_ioctl_helper; +static void dtrace_load(void *); +static int dtrace_unload(void); +static struct cdev *dtrace_dev; +static struct cdev *helper_dev; + +void dtrace_invop_init(void); +void dtrace_invop_uninit(void); + +static struct cdevsw dtrace_cdevsw = { + .d_version = D_VERSION, + .d_ioctl = dtrace_ioctl, + .d_open = dtrace_open, + .d_name = "dtrace", +}; + +static struct cdevsw helper_cdevsw = { + .d_version = D_VERSION, + .d_ioctl = dtrace_ioctl_helper, + .d_name = "helper", +}; + +#include <dtrace_anon.c> +#include <dtrace_ioctl.c> +#include <dtrace_load.c> +#include <dtrace_modevent.c> +#include <dtrace_sysctl.c> +#include <dtrace_unload.c> +#include <dtrace_vtime.c> +#include <dtrace_hacks.c> +#include <dtrace_isa.c> + +SYSINIT(dtrace_load, SI_SUB_DTRACE, SI_ORDER_FIRST, dtrace_load, NULL); +SYSUNINIT(dtrace_unload, SI_SUB_DTRACE, SI_ORDER_FIRST, dtrace_unload, NULL); +SYSINIT(dtrace_anon_init, SI_SUB_DTRACE_ANON, SI_ORDER_FIRST, dtrace_anon_init, NULL); + +DEV_MODULE(dtrace, dtrace_modevent, NULL); +MODULE_VERSION(dtrace, 1); +MODULE_DEPEND(dtrace, opensolaris, 1, 1, 1); +#endif |