/*-
* Copyright (c) 2014 Gleb Smirnoff <glebius@FreeBSD.org>
* Copyright (c) 2003-2004 Alan L. Cox <alc@cs.rice.edu>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _SYS_SF_BUF_H_
#define _SYS_SF_BUF_H_
struct sfstat { /* sendfile statistics */
uint64_t sf_syscalls; /* times sendfile was called */
uint64_t sf_noiocnt; /* times sendfile didn't require I/O */
uint64_t sf_iocnt; /* times sendfile had to do disk I/O */
uint64_t sf_pages_read; /* pages read as part of a request */
uint64_t sf_pages_valid; /* pages were valid for a request */
uint64_t sf_rhpages_requested; /* readahead pages requested */
uint64_t sf_rhpages_read; /* readahead pages read */
uint64_t sf_busy; /* times aborted on a busy page */
uint64_t sf_allocfail; /* times sfbuf allocation failed */
uint64_t sf_allocwait; /* times sfbuf allocation had to wait */
uint64_t sf_pages_bogus; /* times bogus page was used */
};
#ifdef _KERNEL
#include <sys/types.h>
#include <sys/systm.h>
#include <sys/counter.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_page.h>
/*
* Sf_bufs, or sendfile(2) buffers provide a vm_page that is mapped
* into kernel address space. Note, that they aren't used only
* by sendfile(2)!
*
* Sf_bufs could be implemented as a feature of vm_page_t, but that
* would require growth of the structure. That's why they are implemented
* as a separate hash indexed by vm_page address. Implementation lives in
* kern/subr_sfbuf.c. Meanwhile, most 64-bit machines have a physical map,
* so they don't require this hash at all, thus ignore subr_sfbuf.c.
*
* Different 32-bit architectures demand different requirements on sf_buf
* hash and functions. They request features in machine/vmparam.h, which
* enable parts of this file. They can also optionally provide helpers in
* machine/sf_buf.h
*
* Defines are:
* SFBUF This machine requires sf_buf hash.
* subr_sfbuf.c should be compiled.
* SFBUF_CPUSET This machine can perform SFB_CPUPRIVATE mappings,
* that do no invalidate cache on the rest of CPUs.
* SFBUF_NOMD This machine doesn't have machine/sf_buf.h
*
* SFBUF_OPTIONAL_DIRECT_MAP Value of this define is used as boolean
* variable that tells whether machine is
* capable of direct map or not at runtime.
* SFBUF_MAP This machine provides its own sf_buf_map() and
* sf_buf_unmap().
* SFBUF_PROCESS_PAGE This machine provides sf_buf_process_page()
* function.
*/
#ifdef SFBUF
#if defined(SMP) && defined(SFBUF_CPUSET)
#include <sys/_cpuset.h>
#endif
#include <sys/queue.h>
struct sf_buf {
LIST_ENTRY(sf_buf) list_entry; /* list of buffers */
TAILQ_ENTRY(sf_buf) free_entry; /* list of buffers */
vm_page_t m; /* currently mapped page */
vm_offset_t kva; /* va of mapping */
int ref_count; /* usage of this mapping */
#if defined(SMP) && defined(SFBUF_CPUSET)
cpuset_t cpumask; /* where mapping is valid */
#endif
};
#else /* ! SFBUF */
struct sf_buf;
#endif /* SFBUF */
#ifndef SFBUF_NOMD
#include <machine/sf_buf.h>
#endif
#ifdef SFBUF_OPTIONAL_DIRECT_MAP
#include <machine/md_var.h>
#endif
#ifdef SFBUF
struct sf_buf *sf_buf_alloc(struct vm_page *, int);
void sf_buf_free(struct sf_buf *);
void sf_buf_ref(struct sf_buf *);
static inline vm_offset_t
sf_buf_kva(struct sf_buf *sf)
{
#ifdef SFBUF_OPTIONAL_DIRECT_MAP
if (SFBUF_OPTIONAL_DIRECT_MAP)
return (SFBUF_PHYS_DMAP(VM_PAGE_TO_PHYS((vm_page_t)sf)));
#endif
return (sf->kva);
}
static inline vm_page_t
sf_buf_page(struct sf_buf *sf)
{
#ifdef SFBUF_OPTIONAL_DIRECT_MAP
if (SFBUF_OPTIONAL_DIRECT_MAP)
return ((vm_page_t)sf);
#endif
return (sf->m);
}
#ifndef SFBUF_MAP
#include <vm/pmap.h>
static inline void
sf_buf_map(struct sf_buf *sf, int flags)
{
pmap_qenter(sf->kva, &sf->m, 1);
}
static inline int
sf_buf_unmap(struct sf_buf *sf)
{
return (0);
}
#endif /* SFBUF_MAP */
#if defined(SMP) && defined(SFBUF_CPUSET)
void sf_buf_shootdown(struct sf_buf *, int);
#endif
#ifdef SFBUF_PROCESS_PAGE
boolean_t sf_buf_process_page(vm_page_t, void (*)(struct sf_buf *));
#endif
#else /* ! SFBUF */
static inline struct sf_buf *
sf_buf_alloc(struct vm_page *m, int pri)
{
return ((struct sf_buf *)m);
}
static inline void
sf_buf_free(struct sf_buf *sf)
{
}
static inline void
sf_buf_ref(struct sf_buf *sf)
{
}
#endif /* SFBUF */
/*
* Options to sf_buf_alloc() are specified through its flags argument. This
* argument's value should be the result of a bitwise or'ing of one or more
* of the following values.
*/
#define SFB_CATCH 1 /* Check signals if the allocation
sleeps. */
#define SFB_CPUPRIVATE 2 /* Create a CPU private mapping. */
#define SFB_DEFAULT 0
#define SFB_NOWAIT 4 /* Return NULL if all bufs are used. */
extern counter_u64_t sfstat[sizeof(struct sfstat) / sizeof(uint64_t)];
#define SFSTAT_ADD(name, val) \
counter_u64_add(sfstat[offsetof(struct sfstat, name) / sizeof(uint64_t)],\
(val))
#define SFSTAT_INC(name) SFSTAT_ADD(name, 1)
#endif /* _KERNEL */
#endif /* !_SYS_SF_BUF_H_ */
