/*- * Copyright (c) 1991, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * The Mach Operating System project at Carnegie-Mellon University. * * 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. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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. * * from: @(#)vm_page.h 8.2 (Berkeley) 12/13/93 * * * Copyright (c) 1987, 1990 Carnegie-Mellon University. * All rights reserved. * * Authors: Avadis Tevanian, Jr., Michael Wayne Young * * Permission to use, copy, modify and distribute this software and * its documentation is hereby granted, provided that both the copyright * notice and this permission notice appear in all copies of the * software, derivative works or modified versions, and any portions * thereof, and that both notices appear in supporting documentation. * * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. * * Carnegie Mellon requests users of this software to return to * * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU * School of Computer Science * Carnegie Mellon University * Pittsburgh PA 15213-3890 * * any improvements or extensions that they make and grant Carnegie the * rights to redistribute these changes. * * $FreeBSD$ */ /* * Resident memory system definitions. */ #ifndef _VM_PAGE_ #define _VM_PAGE_ #include /* * Management of resident (logical) pages. * * A small structure is kept for each resident * page, indexed by page number. Each structure * is an element of several lists: * * A hash table bucket used to quickly * perform object/offset lookups * * A list of all pages for a given object, * so they can be quickly deactivated at * time of deallocation. * * An ordered list of pages due for pageout. * * In addition, the structure contains the object * and offset to which this page belongs (for pageout), * and sundry status bits. * * In general, operations on this structure's mutable fields are * synchronized using either one of or a combination of the lock on the * object that the page belongs to (O), the pool lock for the page (P), * or the lock for either the free or paging queue (Q). If a field is * annotated below with two of these locks, then holding either lock is * sufficient for read access, but both locks are required for write * access. * * In contrast, the synchronization of accesses to the page's * dirty field is machine dependent (M). In the * machine-independent layer, the lock on the object that the * page belongs to must be held in order to operate on the field. * However, the pmap layer is permitted to set all bits within * the field without holding that lock. If the underlying * architecture does not support atomic read-modify-write * operations on the field's type, then the machine-independent * layer uses a 32-bit atomic on the aligned 32-bit word that * contains the dirty field. In the machine-independent layer, * the implementation of read-modify-write operations on the * field is encapsulated in vm_page_clear_dirty_mask(). */ #if PAGE_SIZE == 4096 #define VM_PAGE_BITS_ALL 0xffu typedef uint8_t vm_page_bits_t; #elif PAGE_SIZE == 8192 #define VM_PAGE_BITS_ALL 0xffffu typedef uint16_t vm_page_bits_t; #elif PAGE_SIZE == 16384 #define VM_PAGE_BITS_ALL 0xffffffffu typedef uint32_t vm_page_bits_t; #elif PAGE_SIZE == 32768 #define VM_PAGE_BITS_ALL 0xfffffffffffffffflu typedef uint64_t vm_page_bits_t; #endif struct vm_page { TAILQ_ENTRY(vm_page) pageq; /* page queue or free list (Q) */ TAILQ_ENTRY(vm_page) listq; /* pages in same object (O) */ vm_object_t object; /* which object am I in (O,P)*/ vm_pindex_t pindex; /* offset into object (O,P) */ vm_paddr_t phys_addr; /* physical address of page */ struct md_page md; /* machine dependant stuff */ uint8_t queue; /* page queue index (P,Q) */ int8_t segind; short hold_count; /* page hold count (P) */ uint8_t order; /* index of the buddy queue */ uint8_t pool; u_short cow; /* page cow mapping count (P) */ u_int wire_count; /* wired down maps refs (P) */ uint8_t aflags; /* access is atomic */ uint8_t oflags; /* page VPO_* flags (O) */ uint16_t flags; /* page PG_* flags (P) */ u_char act_count; /* page usage count (P) */ u_char busy; /* page busy count (O) */ /* NOTE that these must support one bit per DEV_BSIZE in a page!!! */ /* so, on normal X86 kernels, they must be at least 8 bits wide */ vm_page_bits_t valid; /* map of valid DEV_BSIZE chunks (O) */ vm_page_bits_t dirty; /* map of dirty DEV_BSIZE chunks (M) */ }; /* * Page flags stored in oflags: * * Access to these page flags is synchronized by the lock on the object * containing the page (O). * * Note: VPO_UNMANAGED (used by OBJT_DEVICE, OBJT_PHYS and OBJT_SG) * indicates that the page is not under PV management but * otherwise should be treated as a normal page. Pages not * under PV management cannot be paged out via the * object/vm_page_t because there is no knowledge of their pte * mappings, and such pages are also not on any PQ queue. * */ #define VPO_BUSY 0x01 /* page is in transit */ #define VPO_WANTED 0x02 /* someone is waiting for page */ #define VPO_UNMANAGED 0x04 /* no PV management for page */ #define VPO_SWAPINPROG 0x08 /* swap I/O in progress on page */ #define VPO_NOSYNC 0x10 /* do not collect for syncer */ #define PQ_NONE 255 #define PQ_INACTIVE 0 #define PQ_ACTIVE 1 #define PQ_COUNT 2 TAILQ_HEAD(pglist, vm_page); struct vm_pagequeue { struct mtx pq_mutex; struct pglist pq_pl; int *const pq_cnt; const char *const pq_name; } __aligned(CACHE_LINE_SIZE); extern struct vm_pagequeue vm_pagequeues[PQ_COUNT]; #define vm_pagequeue_assert_locked(pq) mtx_assert(&(pq)->pq_mutex, MA_OWNED) #define vm_pagequeue_init_lock(pq) mtx_init(&(pq)->pq_mutex, \ (pq)->pq_name, "vm pagequeue", MTX_DEF | MTX_DUPOK); #define vm_pagequeue_lock(pq) mtx_lock(&(pq)->pq_mutex) #define vm_pagequeue_unlock(pq) mtx_unlock(&(pq)->pq_mutex) extern struct mtx_padalign vm_page_queue_free_mtx; extern struct mtx_padalign pa_lock[]; #if defined(__arm__) #define PDRSHIFT PDR_SHIFT #elif !defined(PDRSHIFT) #define PDRSHIFT 21 #endif #define pa_index(pa) ((pa) >> PDRSHIFT) #define PA_LOCKPTR(pa) ((struct mtx *)(&pa_lock[pa_index(pa) % PA_LOCK_COUNT])) #define PA_LOCKOBJPTR(pa) ((struct lock_object *)PA_LOCKPTR((pa))) #define PA_LOCK(pa) mtx_lock(PA_LOCKPTR(pa)) #define PA_TRYLOCK(pa) mtx_trylock(PA_LOCKPTR(pa)) #define PA_UNLOCK(pa) mtx_unlock(PA_LOCKPTR(pa)) #define PA_UNLOCK_COND(pa) \ do { \ if ((pa) != 0) { \ PA_UNLOCK((pa)); \ (pa) = 0; \ } \ } while (0) #define PA_LOCK_ASSERT(pa, a) mtx_assert(PA_LOCKPTR(pa), (a)) #ifdef KLD_MODULE #define vm_page_lock(m) vm_page_lock_KBI((m), LOCK_FILE, LOCK_LINE) #define vm_page_unlock(m) vm_page_unlock_KBI((m), LOCK_FILE, LOCK_LINE) #define vm_page_trylock(m) vm_page_trylock_KBI((m), LOCK_FILE, LOCK_LINE) #if defined(INVARIANTS) #define vm_page_lock_assert(m, a) \ vm_page_lock_assert_KBI((m), (a), __FILE__, __LINE__) #else #define vm_page_lock_assert(m, a) #endif #else /* !KLD_MODULE */ #define vm_page_lockptr(m) (PA_LOCKPTR(VM_PAGE_TO_PHYS((m)))) #define vm_page_lock(m) mtx_lock(vm_page_lockptr((m))) #define vm_page_unlock(m) mtx_unlock(vm_page_lockptr((m))) #define vm_page_trylock(m) mtx_trylock(vm_page_lockptr((m))) #define vm_page_lock_assert(m, a) mtx_assert(vm_page_lockptr((m)), (a)) #endif /* * The vm_page's aflags are updated using atomic operations. To set or clear * these flags, the functions vm_page_aflag_set() and vm_page_aflag_clear() * must be used. Neither these flags nor these functions are part of the KBI. * * PGA_REFERENCED may be cleared only if the object containing the page is * locked. It is set by both the MI and MD VM layers. However, kernel * loadable modules should not directly set this flag. They should call * vm_page_reference() instead. * * PGA_WRITEABLE is set exclusively on managed pages by pmap_enter(). When it * does so, the page must be VPO_BUSY. The MI VM layer must never access this * flag directly. Instead, it should call pmap_page_is_write_mapped(). * * PGA_EXECUTABLE may be set by pmap routines, and indicates that a page has * at least one executable mapping. It is not consumed by the MI VM layer. */ #define PGA_WRITEABLE 0x01 /* page may be mapped writeable */ #define PGA_REFERENCED 0x02 /* page has been referenced */ #define PGA_EXECUTABLE 0x04 /* page may be mapped executable */ /* * Page flags. If changed at any other time than page allocation or * freeing, the modification must be protected by the vm_page lock. */ #define PG_CACHED 0x0001 /* page is cached */ #define PG_FREE 0x0002 /* page is free */ #define PG_FICTITIOUS 0x0004 /* physical page doesn't exist */ #define PG_ZERO 0x0008 /* page is zeroed */ #define PG_MARKER 0x0010 /* special queue marker page */ #define PG_SLAB 0x0020 /* object pointer is actually a slab */ #define PG_WINATCFLS 0x0040 /* flush dirty page on inactive q */ #define PG_NODUMP 0x0080 /* don't include this page in a dump */ #define PG_UNHOLDFREE 0x0100 /* delayed free of a held page */ /* * Misc constants. */ #define ACT_DECLINE 1 #define ACT_ADVANCE 3 #define ACT_INIT 5 #define ACT_MAX 64 #ifdef _KERNEL #include #include /* * Each pageable resident page falls into one of four lists: * * free * Available for allocation now. * * cache * Almost available for allocation. Still associated with * an object, but clean and immediately freeable. * * The following lists are LRU sorted: * * inactive * Low activity, candidates for reclamation. * This is the list of pages that should be * paged out next. * * active * Pages that are "active" i.e. they have been * recently referenced. * */ extern int vm_page_zero_count; extern vm_page_t vm_page_array; /* First resident page in table */ extern long vm_page_array_size; /* number of vm_page_t's */ extern long first_page; /* first physical page number */ #define VM_PAGE_IS_FREE(m) (((m)->flags & PG_FREE) != 0) #define VM_PAGE_TO_PHYS(entry) ((entry)->phys_addr) vm_page_t PHYS_TO_VM_PAGE(vm_paddr_t pa); /* page allocation classes: */ #define VM_ALLOC_NORMAL 0 #define VM_ALLOC_INTERRUPT 1 #define VM_ALLOC_SYSTEM 2 #define VM_ALLOC_CLASS_MASK 3 /* page allocation flags: */ #define VM_ALLOC_WIRED 0x0020 /* non pageable */ #define VM_ALLOC_ZERO 0x0040 /* Try to obtain a zeroed page */ #define VM_ALLOC_RETRY 0x0080 /* Mandatory with vm_page_grab() */ #define VM_ALLOC_NOOBJ 0x0100 /* No associated object */ #define VM_ALLOC_NOBUSY 0x0200 /* Do not busy the page */ #define VM_ALLOC_IFCACHED 0x0400 /* Fail if the page is not cached */ #define VM_ALLOC_IFNOTCACHED 0x0800 /* Fail if the page is cached */ #define VM_ALLOC_IGN_SBUSY 0x1000 /* vm_page_grab() only */ #define VM_ALLOC_NODUMP 0x2000 /* don't include in dump */ #define VM_ALLOC_COUNT_SHIFT 16 #define VM_ALLOC_COUNT(count) ((count) << VM_ALLOC_COUNT_SHIFT) #ifdef M_NOWAIT static inline int malloc2vm_flags(int malloc_flags) { int pflags; KASSERT((malloc_flags & M_USE_RESERVE) == 0 || (malloc_flags & M_NOWAIT) != 0, ("M_USE_RESERVE requires M_NOWAIT")); pflags = (malloc_flags & M_USE_RESERVE) != 0 ? VM_ALLOC_INTERRUPT : VM_ALLOC_SYSTEM; if ((malloc_flags & M_ZERO) != 0) pflags |= VM_ALLOC_ZERO; if ((malloc_flags & M_NODUMP) != 0) pflags |= VM_ALLOC_NODUMP; return (pflags); } #endif void vm_page_busy(vm_page_t m); void vm_page_flash(vm_page_t m); void vm_page_io_start(vm_page_t m); void vm_page_io_finish(vm_page_t m); void vm_page_hold(vm_page_t mem); void vm_page_unhold(vm_page_t mem); void vm_page_free(vm_page_t m); void vm_page_free_zero(vm_page_t m); void vm_page_wakeup(vm_page_t m); void vm_page_activate (vm_page_t); vm_page_t vm_page_alloc (vm_object_t, vm_pindex_t, int); vm_page_t vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req, u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary, vm_memattr_t memattr); vm_page_t vm_page_alloc_freelist(int, int); vm_page_t vm_page_grab (vm_object_t, vm_pindex_t, int); void vm_page_cache(vm_page_t); void vm_page_cache_free(vm_object_t, vm_pindex_t, vm_pindex_t); void vm_page_cache_transfer(vm_object_t, vm_pindex_t, vm_object_t); int vm_page_try_to_cache (vm_page_t); int vm_page_try_to_free (vm_page_t); void vm_page_dontneed(vm_page_t); void vm_page_deactivate (vm_page_t); void vm_page_dequeue(vm_page_t m); void vm_page_dequeue_locked(vm_page_t m); vm_page_t vm_page_find_least(vm_object_t, vm_pindex_t); vm_page_t vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr); void vm_page_initfake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr); void vm_page_insert (vm_page_t, vm_object_t, vm_pindex_t); boolean_t vm_page_is_cached(vm_object_t object, vm_pindex_t pindex); vm_page_t vm_page_lookup (vm_object_t, vm_pindex_t); vm_page_t vm_page_next(vm_page_t m); int vm_page_pa_tryrelock(pmap_t, vm_paddr_t, vm_paddr_t *); vm_page_t vm_page_prev(vm_page_t m); void vm_page_putfake(vm_page_t m); void vm_page_readahead_finish(vm_page_t m); void vm_page_reference(vm_page_t m); void vm_page_remove (vm_page_t); void vm_page_rename (vm_page_t, vm_object_t, vm_pindex_t); void vm_page_requeue(vm_page_t m); void vm_page_requeue_locked(vm_page_t m); void vm_page_set_valid_range(vm_page_t m, int base, int size); void vm_page_sleep(vm_page_t m, const char *msg); vm_offset_t vm_page_startup(vm_offset_t vaddr); void vm_page_unhold_pages(vm_page_t *ma, int count); void vm_page_unwire (vm_page_t, int); void vm_page_updatefake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr); void vm_page_wire (vm_page_t); void vm_page_set_validclean (vm_page_t, int, int); void vm_page_clear_dirty (vm_page_t, int, int); void vm_page_set_invalid (vm_page_t, int, int); int vm_page_is_valid (vm_page_t, int, int); void vm_page_test_dirty (vm_page_t); vm_page_bits_t vm_page_bits(int base, int size); void vm_page_zero_invalid(vm_page_t m, boolean_t setvalid); void vm_page_free_toq(vm_page_t m); void vm_page_zero_idle_wakeup(void); void vm_page_cowfault (vm_page_t); int vm_page_cowsetup(vm_page_t); void vm_page_cowclear (vm_page_t); void vm_page_dirty_KBI(vm_page_t m); void vm_page_lock_KBI(vm_page_t m, const char *file, int line); void vm_page_unlock_KBI(vm_page_t m, const char *file, int line); int vm_page_trylock_KBI(vm_page_t m, const char *file, int line); #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT) void vm_page_lock_assert_KBI(vm_page_t m, int a, const char *file, int line); #endif #ifdef INVARIANTS void vm_page_object_lock_assert(vm_page_t m); #define VM_PAGE_OBJECT_LOCK_ASSERT(m) vm_page_object_lock_assert(m) #else #define VM_PAGE_OBJECT_LOCK_ASSERT(m) (void)0 #endif /* * We want to use atomic updates for the aflags field, which is 8 bits wide. * However, not all architectures support atomic operations on 8-bit * destinations. In order that we can easily use a 32-bit operation, we * require that the aflags field be 32-bit aligned. */ CTASSERT(offsetof(struct vm_page, aflags) % sizeof(uint32_t) == 0); /* * Clear the given bits in the specified page. */ static inline void vm_page_aflag_clear(vm_page_t m, uint8_t bits) { uint32_t *addr, val; /* * The PGA_REFERENCED flag can only be cleared if the object * containing the page is locked. */ if ((bits & PGA_REFERENCED) != 0) VM_PAGE_OBJECT_LOCK_ASSERT(m); /* * Access the whole 32-bit word containing the aflags field with an * atomic update. Parallel non-atomic updates to the other fields * within this word are handled properly by the atomic update. */ addr = (void *)&m->aflags; KASSERT(((uintptr_t)addr & (sizeof(uint32_t) - 1)) == 0, ("vm_page_aflag_clear: aflags is misaligned")); val = bits; #if BYTE_ORDER == BIG_ENDIAN val <<= 24; #endif atomic_clear_32(addr, val); } /* * Set the given bits in the specified page. */ static inline void vm_page_aflag_set(vm_page_t m, uint8_t bits) { uint32_t *addr, val; /* * The PGA_WRITEABLE flag can only be set if the page is managed and * VPO_BUSY. Currently, this flag is only set by pmap_enter(). */ KASSERT((bits & PGA_WRITEABLE) == 0 || (m->oflags & (VPO_UNMANAGED | VPO_BUSY)) == VPO_BUSY, ("vm_page_aflag_set: PGA_WRITEABLE and !VPO_BUSY")); /* * Access the whole 32-bit word containing the aflags field with an * atomic update. Parallel non-atomic updates to the other fields * within this word are handled properly by the atomic update. */ addr = (void *)&m->aflags; KASSERT(((uintptr_t)addr & (sizeof(uint32_t) - 1)) == 0, ("vm_page_aflag_set: aflags is misaligned")); val = bits; #if BYTE_ORDER == BIG_ENDIAN val <<= 24; #endif atomic_set_32(addr, val); } /* * vm_page_dirty: * * Set all bits in the page's dirty field. * * The object containing the specified page must be locked if the * call is made from the machine-independent layer. * * See vm_page_clear_dirty_mask(). */ static __inline void vm_page_dirty(vm_page_t m) { /* Use vm_page_dirty_KBI() under INVARIANTS to save memory. */ #if defined(KLD_MODULE) || defined(INVARIANTS) vm_page_dirty_KBI(m); #else m->dirty = VM_PAGE_BITS_ALL; #endif } /* * vm_page_remque: * * If the given page is in a page queue, then remove it from that page * queue. * * The page must be locked. */ static inline void vm_page_remque(vm_page_t m) { if (m->queue != PQ_NONE) vm_page_dequeue(m); } /* * vm_page_sleep_if_busy: * * Sleep and release the page queues lock if VPO_BUSY is set or, * if also_m_busy is TRUE, busy is non-zero. Returns TRUE if the * thread slept and the page queues lock was released. * Otherwise, retains the page queues lock and returns FALSE. * * The object containing the given page must be locked. */ static __inline int vm_page_sleep_if_busy(vm_page_t m, int also_m_busy, const char *msg) { if ((m->oflags & VPO_BUSY) || (also_m_busy && m->busy)) { vm_page_sleep(m, msg); return (TRUE); } return (FALSE); } /* * vm_page_undirty: * * Set page to not be dirty. Note: does not clear pmap modify bits */ static __inline void vm_page_undirty(vm_page_t m) { VM_PAGE_OBJECT_LOCK_ASSERT(m); m->dirty = 0; } #endif /* _KERNEL */ #endif /* !_VM_PAGE_ */