2 * SPDX-License-Identifier: (BSD-3-Clause AND MIT-CMU)
4 * Copyright (c) 1991, 1993
5 * The Regents of the University of California. All rights reserved.
7 * This code is derived from software contributed to Berkeley by
8 * The Mach Operating System project at Carnegie-Mellon University.
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11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
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17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * from: @(#)vm_page.h 8.2 (Berkeley) 12/13/93
37 * Copyright (c) 1987, 1990 Carnegie-Mellon University.
38 * All rights reserved.
40 * Authors: Avadis Tevanian, Jr., Michael Wayne Young
42 * Permission to use, copy, modify and distribute this software and
43 * its documentation is hereby granted, provided that both the copyright
44 * notice and this permission notice appear in all copies of the
45 * software, derivative works or modified versions, and any portions
46 * thereof, and that both notices appear in supporting documentation.
48 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
49 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
50 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
52 * Carnegie Mellon requests users of this software to return to
54 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
55 * School of Computer Science
56 * Carnegie Mellon University
57 * Pittsburgh PA 15213-3890
59 * any improvements or extensions that they make and grant Carnegie the
60 * rights to redistribute these changes.
66 * Resident memory system definitions.
75 * Management of resident (logical) pages.
77 * A small structure is kept for each resident
78 * page, indexed by page number. Each structure
79 * is an element of several collections:
81 * A radix tree used to quickly
82 * perform object/offset lookups
84 * A list of all pages for a given object,
85 * so they can be quickly deactivated at
86 * time of deallocation.
88 * An ordered list of pages due for pageout.
90 * In addition, the structure contains the object
91 * and offset to which this page belongs (for pageout),
92 * and sundry status bits.
94 * In general, operations on this structure's mutable fields are
95 * synchronized using either one of or a combination of the lock on the
96 * object that the page belongs to (O), the pool lock for the page (P),
97 * or the lock for either the free or paging queue (Q). If a field is
98 * annotated below with two of these locks, then holding either lock is
99 * sufficient for read access, but both locks are required for write
100 * access. An annotation of (C) indicates that the field is immutable.
102 * In contrast, the synchronization of accesses to the page's
103 * dirty field is machine dependent (M). In the
104 * machine-independent layer, the lock on the object that the
105 * page belongs to must be held in order to operate on the field.
106 * However, the pmap layer is permitted to set all bits within
107 * the field without holding that lock. If the underlying
108 * architecture does not support atomic read-modify-write
109 * operations on the field's type, then the machine-independent
110 * layer uses a 32-bit atomic on the aligned 32-bit word that
111 * contains the dirty field. In the machine-independent layer,
112 * the implementation of read-modify-write operations on the
113 * field is encapsulated in vm_page_clear_dirty_mask().
115 * The page structure contains two counters which prevent page reuse.
116 * Both counters are protected by the page lock (P). The hold
117 * counter counts transient references obtained via a pmap lookup, and
118 * is also used to prevent page reclamation in situations where it is
119 * undesirable to block other accesses to the page. The wire counter
120 * is used to implement mlock(2) and is non-zero for pages containing
121 * kernel memory. Pages that are wired or held will not be reclaimed
122 * or laundered by the page daemon, but are treated differently during
123 * a page queue scan: held pages remain at their position in the queue,
124 * while wired pages are removed from the queue and must later be
125 * re-enqueued appropriately by the unwiring thread. It is legal to
126 * call vm_page_free() on a held page; doing so causes it to be removed
127 * from its object and page queue, and the page is released to the
128 * allocator once the last hold reference is dropped. In contrast,
129 * wired pages may not be freed.
131 * In some pmap implementations, the wire count of a page table page is
132 * used to track the number of populated entries.
134 * The busy lock is an embedded reader-writer lock which protects the
135 * page's contents and identity (i.e., its <object, pindex> tuple) and
136 * interlocks with the object lock (O). In particular, a page may be
137 * busied or unbusied only with the object write lock held. To avoid
138 * bloating the page structure, the busy lock lacks some of the
139 * features available to the kernel's general-purpose synchronization
140 * primitives. As a result, busy lock ordering rules are not verified,
141 * lock recursion is not detected, and an attempt to xbusy a busy page
142 * or sbusy an xbusy page results will trigger a panic rather than
143 * causing the thread to block. vm_page_sleep_if_busy() can be used to
144 * sleep until the page's busy state changes, after which the caller
145 * must re-lookup the page and re-evaluate its state.
148 #if PAGE_SIZE == 4096
149 #define VM_PAGE_BITS_ALL 0xffu
150 typedef uint8_t vm_page_bits_t;
151 #elif PAGE_SIZE == 8192
152 #define VM_PAGE_BITS_ALL 0xffffu
153 typedef uint16_t vm_page_bits_t;
154 #elif PAGE_SIZE == 16384
155 #define VM_PAGE_BITS_ALL 0xffffffffu
156 typedef uint32_t vm_page_bits_t;
157 #elif PAGE_SIZE == 32768
158 #define VM_PAGE_BITS_ALL 0xfffffffffffffffflu
159 typedef uint64_t vm_page_bits_t;
164 TAILQ_ENTRY(vm_page) q; /* page queue or free list (Q) */
166 SLIST_ENTRY(vm_page) ss; /* private slists */
174 TAILQ_ENTRY(vm_page) listq; /* pages in same object (O) */
175 vm_object_t object; /* which object am I in (O,P) */
176 vm_pindex_t pindex; /* offset into object (O,P) */
177 vm_paddr_t phys_addr; /* physical address of page */
178 struct md_page md; /* machine dependent stuff */
179 u_int wire_count; /* wired down maps refs (P) */
180 volatile u_int busy_lock; /* busy owners lock */
181 uint16_t hold_count; /* page hold count (P) */
182 uint16_t flags; /* page PG_* flags (P) */
183 uint8_t aflags; /* access is atomic */
184 uint8_t oflags; /* page VPO_* flags (O) */
185 uint8_t queue; /* page queue index (P,Q) */
186 int8_t psind; /* pagesizes[] index (O) */
187 int8_t segind; /* vm_phys segment index (C) */
188 uint8_t order; /* index of the buddy queue */
189 uint8_t pool; /* vm_phys freepool index (Q) */
190 u_char act_count; /* page usage count (P) */
191 /* NOTE that these must support one bit per DEV_BSIZE in a page */
192 /* so, on normal X86 kernels, they must be at least 8 bits wide */
193 vm_page_bits_t valid; /* map of valid DEV_BSIZE chunks (O) */
194 vm_page_bits_t dirty; /* map of dirty DEV_BSIZE chunks (M) */
198 * Page flags stored in oflags:
200 * Access to these page flags is synchronized by the lock on the object
201 * containing the page (O).
203 * Note: VPO_UNMANAGED (used by OBJT_DEVICE, OBJT_PHYS and OBJT_SG)
204 * indicates that the page is not under PV management but
205 * otherwise should be treated as a normal page. Pages not
206 * under PV management cannot be paged out via the
207 * object/vm_page_t because there is no knowledge of their pte
208 * mappings, and such pages are also not on any PQ queue.
211 #define VPO_UNUSED01 0x01 /* --available-- */
212 #define VPO_SWAPSLEEP 0x02 /* waiting for swap to finish */
213 #define VPO_UNMANAGED 0x04 /* no PV management for page */
214 #define VPO_SWAPINPROG 0x08 /* swap I/O in progress on page */
215 #define VPO_NOSYNC 0x10 /* do not collect for syncer */
218 * Busy page implementation details.
219 * The algorithm is taken mostly by rwlock(9) and sx(9) locks implementation,
220 * even if the support for owner identity is removed because of size
221 * constraints. Checks on lock recursion are then not possible, while the
222 * lock assertions effectiveness is someway reduced.
224 #define VPB_BIT_SHARED 0x01
225 #define VPB_BIT_EXCLUSIVE 0x02
226 #define VPB_BIT_WAITERS 0x04
227 #define VPB_BIT_FLAGMASK \
228 (VPB_BIT_SHARED | VPB_BIT_EXCLUSIVE | VPB_BIT_WAITERS)
230 #define VPB_SHARERS_SHIFT 3
231 #define VPB_SHARERS(x) \
232 (((x) & ~VPB_BIT_FLAGMASK) >> VPB_SHARERS_SHIFT)
233 #define VPB_SHARERS_WORD(x) ((x) << VPB_SHARERS_SHIFT | VPB_BIT_SHARED)
234 #define VPB_ONE_SHARER (1 << VPB_SHARERS_SHIFT)
236 #define VPB_SINGLE_EXCLUSIVER VPB_BIT_EXCLUSIVE
238 #define VPB_UNBUSIED VPB_SHARERS_WORD(0)
241 #define PQ_INACTIVE 0
244 #define PQ_UNSWAPPABLE 3
247 #ifndef VM_PAGE_HAVE_PGLIST
248 TAILQ_HEAD(pglist, vm_page);
249 #define VM_PAGE_HAVE_PGLIST
251 SLIST_HEAD(spglist, vm_page);
254 extern vm_page_t bogus_page;
257 extern struct mtx_padalign pa_lock[];
260 #define PDRSHIFT PDR_SHIFT
261 #elif !defined(PDRSHIFT)
265 #define pa_index(pa) ((pa) >> PDRSHIFT)
266 #define PA_LOCKPTR(pa) ((struct mtx *)(&pa_lock[pa_index(pa) % PA_LOCK_COUNT]))
267 #define PA_LOCKOBJPTR(pa) ((struct lock_object *)PA_LOCKPTR((pa)))
268 #define PA_LOCK(pa) mtx_lock(PA_LOCKPTR(pa))
269 #define PA_TRYLOCK(pa) mtx_trylock(PA_LOCKPTR(pa))
270 #define PA_UNLOCK(pa) mtx_unlock(PA_LOCKPTR(pa))
271 #define PA_UNLOCK_COND(pa) \
279 #define PA_LOCK_ASSERT(pa, a) mtx_assert(PA_LOCKPTR(pa), (a))
282 #define vm_page_lock(m) vm_page_lock_KBI((m), LOCK_FILE, LOCK_LINE)
283 #define vm_page_unlock(m) vm_page_unlock_KBI((m), LOCK_FILE, LOCK_LINE)
284 #define vm_page_trylock(m) vm_page_trylock_KBI((m), LOCK_FILE, LOCK_LINE)
285 #else /* !KLD_MODULE */
286 #define vm_page_lockptr(m) (PA_LOCKPTR(VM_PAGE_TO_PHYS((m))))
287 #define vm_page_lock(m) mtx_lock(vm_page_lockptr((m)))
288 #define vm_page_unlock(m) mtx_unlock(vm_page_lockptr((m)))
289 #define vm_page_trylock(m) mtx_trylock(vm_page_lockptr((m)))
291 #if defined(INVARIANTS)
292 #define vm_page_assert_locked(m) \
293 vm_page_assert_locked_KBI((m), __FILE__, __LINE__)
294 #define vm_page_lock_assert(m, a) \
295 vm_page_lock_assert_KBI((m), (a), __FILE__, __LINE__)
297 #define vm_page_assert_locked(m)
298 #define vm_page_lock_assert(m, a)
302 * The vm_page's aflags are updated using atomic operations. To set or clear
303 * these flags, the functions vm_page_aflag_set() and vm_page_aflag_clear()
304 * must be used. Neither these flags nor these functions are part of the KBI.
306 * PGA_REFERENCED may be cleared only if the page is locked. It is set by
307 * both the MI and MD VM layers. However, kernel loadable modules should not
308 * directly set this flag. They should call vm_page_reference() instead.
310 * PGA_WRITEABLE is set exclusively on managed pages by pmap_enter().
311 * When it does so, the object must be locked, or the page must be
312 * exclusive busied. The MI VM layer must never access this flag
313 * directly. Instead, it should call pmap_page_is_write_mapped().
315 * PGA_EXECUTABLE may be set by pmap routines, and indicates that a page has
316 * at least one executable mapping. It is not consumed by the MI VM layer.
318 #define PGA_WRITEABLE 0x01 /* page may be mapped writeable */
319 #define PGA_REFERENCED 0x02 /* page has been referenced */
320 #define PGA_EXECUTABLE 0x04 /* page may be mapped executable */
323 * Page flags. If changed at any other time than page allocation or
324 * freeing, the modification must be protected by the vm_page lock.
326 #define PG_FICTITIOUS 0x0004 /* physical page doesn't exist */
327 #define PG_ZERO 0x0008 /* page is zeroed */
328 #define PG_MARKER 0x0010 /* special queue marker page */
329 #define PG_NODUMP 0x0080 /* don't include this page in a dump */
330 #define PG_UNHOLDFREE 0x0100 /* delayed free of a held page */
335 #define ACT_DECLINE 1
336 #define ACT_ADVANCE 3
342 #include <sys/systm.h>
344 #include <machine/atomic.h>
347 * Each pageable resident page falls into one of five lists:
350 * Available for allocation now.
353 * Low activity, candidates for reclamation.
354 * This list is approximately LRU ordered.
357 * This is the list of pages that should be
361 * Dirty anonymous pages that cannot be paged
362 * out because no swap device is configured.
365 * Pages that are "active", i.e., they have been
366 * recently referenced.
370 extern vm_page_t vm_page_array; /* First resident page in table */
371 extern long vm_page_array_size; /* number of vm_page_t's */
372 extern long first_page; /* first physical page number */
374 #define VM_PAGE_TO_PHYS(entry) ((entry)->phys_addr)
377 * PHYS_TO_VM_PAGE() returns the vm_page_t object that represents a memory
378 * page to which the given physical address belongs. The correct vm_page_t
379 * object is returned for addresses that are not page-aligned.
381 vm_page_t PHYS_TO_VM_PAGE(vm_paddr_t pa);
384 * Page allocation parameters for vm_page for the functions
385 * vm_page_alloc(), vm_page_grab(), vm_page_alloc_contig() and
386 * vm_page_alloc_freelist(). Some functions support only a subset
387 * of the flags, and ignore others, see the flags legend.
389 * The meaning of VM_ALLOC_ZERO differs slightly between the vm_page_alloc*()
390 * and the vm_page_grab*() functions. See these functions for details.
392 * Bits 0 - 1 define class.
393 * Bits 2 - 15 dedicated for flags.
395 * (a) - vm_page_alloc() supports the flag.
396 * (c) - vm_page_alloc_contig() supports the flag.
397 * (f) - vm_page_alloc_freelist() supports the flag.
398 * (g) - vm_page_grab() supports the flag.
399 * (p) - vm_page_grab_pages() supports the flag.
400 * Bits above 15 define the count of additional pages that the caller
401 * intends to allocate.
403 #define VM_ALLOC_NORMAL 0
404 #define VM_ALLOC_INTERRUPT 1
405 #define VM_ALLOC_SYSTEM 2
406 #define VM_ALLOC_CLASS_MASK 3
407 #define VM_ALLOC_WAITOK 0x0008 /* (acf) Sleep and retry */
408 #define VM_ALLOC_WAITFAIL 0x0010 /* (acf) Sleep and return error */
409 #define VM_ALLOC_WIRED 0x0020 /* (acfgp) Allocate a wired page */
410 #define VM_ALLOC_ZERO 0x0040 /* (acfgp) Allocate a prezeroed page */
411 #define VM_ALLOC_NOOBJ 0x0100 /* (acg) No associated object */
412 #define VM_ALLOC_NOBUSY 0x0200 /* (acgp) Do not excl busy the page */
413 #define VM_ALLOC_IGN_SBUSY 0x1000 /* (gp) Ignore shared busy flag */
414 #define VM_ALLOC_NODUMP 0x2000 /* (ag) don't include in dump */
415 #define VM_ALLOC_SBUSY 0x4000 /* (acgp) Shared busy the page */
416 #define VM_ALLOC_NOWAIT 0x8000 /* (acfgp) Do not sleep */
417 #define VM_ALLOC_COUNT_SHIFT 16
418 #define VM_ALLOC_COUNT(count) ((count) << VM_ALLOC_COUNT_SHIFT)
422 malloc2vm_flags(int malloc_flags)
426 KASSERT((malloc_flags & M_USE_RESERVE) == 0 ||
427 (malloc_flags & M_NOWAIT) != 0,
428 ("M_USE_RESERVE requires M_NOWAIT"));
429 pflags = (malloc_flags & M_USE_RESERVE) != 0 ? VM_ALLOC_INTERRUPT :
431 if ((malloc_flags & M_ZERO) != 0)
432 pflags |= VM_ALLOC_ZERO;
433 if ((malloc_flags & M_NODUMP) != 0)
434 pflags |= VM_ALLOC_NODUMP;
435 if ((malloc_flags & M_NOWAIT))
436 pflags |= VM_ALLOC_NOWAIT;
437 if ((malloc_flags & M_WAITOK))
438 pflags |= VM_ALLOC_WAITOK;
444 * Predicates supported by vm_page_ps_test():
446 * PS_ALL_DIRTY is true only if the entire (super)page is dirty.
447 * However, it can be spuriously false when the (super)page has become
448 * dirty in the pmap but that information has not been propagated to the
449 * machine-independent layer.
451 #define PS_ALL_DIRTY 0x1
452 #define PS_ALL_VALID 0x2
453 #define PS_NONE_BUSY 0x4
455 void vm_page_busy_downgrade(vm_page_t m);
456 void vm_page_busy_sleep(vm_page_t m, const char *msg, bool nonshared);
457 void vm_page_flash(vm_page_t m);
458 void vm_page_hold(vm_page_t mem);
459 void vm_page_unhold(vm_page_t mem);
460 void vm_page_free(vm_page_t m);
461 void vm_page_free_zero(vm_page_t m);
463 void vm_page_activate (vm_page_t);
464 void vm_page_advise(vm_page_t m, int advice);
465 vm_page_t vm_page_alloc(vm_object_t, vm_pindex_t, int);
466 vm_page_t vm_page_alloc_domain(vm_object_t, vm_pindex_t, int, int);
467 vm_page_t vm_page_alloc_after(vm_object_t, vm_pindex_t, int, vm_page_t);
468 vm_page_t vm_page_alloc_domain_after(vm_object_t, vm_pindex_t, int, int,
470 vm_page_t vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req,
471 u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment,
472 vm_paddr_t boundary, vm_memattr_t memattr);
473 vm_page_t vm_page_alloc_contig_domain(vm_object_t object,
474 vm_pindex_t pindex, int domain, int req, u_long npages, vm_paddr_t low,
475 vm_paddr_t high, u_long alignment, vm_paddr_t boundary,
476 vm_memattr_t memattr);
477 vm_page_t vm_page_alloc_freelist(int, int);
478 vm_page_t vm_page_alloc_freelist_domain(int, int, int);
479 void vm_page_change_lock(vm_page_t m, struct mtx **mtx);
480 vm_page_t vm_page_grab (vm_object_t, vm_pindex_t, int);
481 int vm_page_grab_pages(vm_object_t object, vm_pindex_t pindex, int allocflags,
482 vm_page_t *ma, int count);
483 void vm_page_deactivate(vm_page_t);
484 void vm_page_deactivate_noreuse(vm_page_t);
485 void vm_page_dequeue(vm_page_t m);
486 void vm_page_dequeue_locked(vm_page_t m);
487 vm_page_t vm_page_find_least(vm_object_t, vm_pindex_t);
488 void vm_page_free_phys_pglist(struct pglist *tq);
489 bool vm_page_free_prep(vm_page_t m, bool pagequeue_locked);
490 vm_page_t vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr);
491 void vm_page_initfake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr);
492 int vm_page_insert (vm_page_t, vm_object_t, vm_pindex_t);
493 void vm_page_launder(vm_page_t m);
494 vm_page_t vm_page_lookup (vm_object_t, vm_pindex_t);
495 vm_page_t vm_page_next(vm_page_t m);
496 int vm_page_pa_tryrelock(pmap_t, vm_paddr_t, vm_paddr_t *);
497 struct vm_pagequeue *vm_page_pagequeue(vm_page_t m);
498 vm_page_t vm_page_prev(vm_page_t m);
499 bool vm_page_ps_test(vm_page_t m, int flags, vm_page_t skip_m);
500 void vm_page_putfake(vm_page_t m);
501 void vm_page_readahead_finish(vm_page_t m);
502 bool vm_page_reclaim_contig(int req, u_long npages, vm_paddr_t low,
503 vm_paddr_t high, u_long alignment, vm_paddr_t boundary);
504 bool vm_page_reclaim_contig_domain(int domain, int req, u_long npages,
505 vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary);
506 void vm_page_reference(vm_page_t m);
507 void vm_page_remove (vm_page_t);
508 int vm_page_rename (vm_page_t, vm_object_t, vm_pindex_t);
509 vm_page_t vm_page_replace(vm_page_t mnew, vm_object_t object,
511 void vm_page_requeue(vm_page_t m);
512 void vm_page_requeue_locked(vm_page_t m);
513 int vm_page_sbusied(vm_page_t m);
514 vm_page_t vm_page_scan_contig(u_long npages, vm_page_t m_start,
515 vm_page_t m_end, u_long alignment, vm_paddr_t boundary, int options);
516 void vm_page_set_valid_range(vm_page_t m, int base, int size);
517 int vm_page_sleep_if_busy(vm_page_t m, const char *msg);
518 vm_offset_t vm_page_startup(vm_offset_t vaddr);
519 void vm_page_sunbusy(vm_page_t m);
520 bool vm_page_try_to_free(vm_page_t m);
521 int vm_page_trysbusy(vm_page_t m);
522 void vm_page_unhold_pages(vm_page_t *ma, int count);
523 void vm_page_unswappable(vm_page_t m);
524 bool vm_page_unwire(vm_page_t m, uint8_t queue);
525 bool vm_page_unwire_noq(vm_page_t m);
526 void vm_page_updatefake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr);
527 void vm_page_wire (vm_page_t);
528 void vm_page_xunbusy_hard(vm_page_t m);
529 void vm_page_xunbusy_maybelocked(vm_page_t m);
530 void vm_page_set_validclean (vm_page_t, int, int);
531 void vm_page_clear_dirty (vm_page_t, int, int);
532 void vm_page_set_invalid (vm_page_t, int, int);
533 int vm_page_is_valid (vm_page_t, int, int);
534 void vm_page_test_dirty (vm_page_t);
535 vm_page_bits_t vm_page_bits(int base, int size);
536 void vm_page_zero_invalid(vm_page_t m, boolean_t setvalid);
537 void vm_page_free_toq(vm_page_t m);
539 void vm_page_dirty_KBI(vm_page_t m);
540 void vm_page_lock_KBI(vm_page_t m, const char *file, int line);
541 void vm_page_unlock_KBI(vm_page_t m, const char *file, int line);
542 int vm_page_trylock_KBI(vm_page_t m, const char *file, int line);
543 #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
544 void vm_page_assert_locked_KBI(vm_page_t m, const char *file, int line);
545 void vm_page_lock_assert_KBI(vm_page_t m, int a, const char *file, int line);
548 #define vm_page_assert_sbusied(m) \
549 KASSERT(vm_page_sbusied(m), \
550 ("vm_page_assert_sbusied: page %p not shared busy @ %s:%d", \
551 (m), __FILE__, __LINE__))
553 #define vm_page_assert_unbusied(m) \
554 KASSERT(!vm_page_busied(m), \
555 ("vm_page_assert_unbusied: page %p busy @ %s:%d", \
556 (m), __FILE__, __LINE__))
558 #define vm_page_assert_xbusied(m) \
559 KASSERT(vm_page_xbusied(m), \
560 ("vm_page_assert_xbusied: page %p not exclusive busy @ %s:%d", \
561 (m), __FILE__, __LINE__))
563 #define vm_page_busied(m) \
564 ((m)->busy_lock != VPB_UNBUSIED)
566 #define vm_page_sbusy(m) do { \
567 if (!vm_page_trysbusy(m)) \
568 panic("%s: page %p failed shared busying", __func__, \
572 #define vm_page_tryxbusy(m) \
573 (atomic_cmpset_acq_int(&(m)->busy_lock, VPB_UNBUSIED, \
574 VPB_SINGLE_EXCLUSIVER))
576 #define vm_page_xbusied(m) \
577 (((m)->busy_lock & VPB_SINGLE_EXCLUSIVER) != 0)
579 #define vm_page_xbusy(m) do { \
580 if (!vm_page_tryxbusy(m)) \
581 panic("%s: page %p failed exclusive busying", __func__, \
585 /* Note: page m's lock must not be owned by the caller. */
586 #define vm_page_xunbusy(m) do { \
587 if (!atomic_cmpset_rel_int(&(m)->busy_lock, \
588 VPB_SINGLE_EXCLUSIVER, VPB_UNBUSIED)) \
589 vm_page_xunbusy_hard(m); \
593 void vm_page_object_lock_assert(vm_page_t m);
594 #define VM_PAGE_OBJECT_LOCK_ASSERT(m) vm_page_object_lock_assert(m)
595 void vm_page_assert_pga_writeable(vm_page_t m, uint8_t bits);
596 #define VM_PAGE_ASSERT_PGA_WRITEABLE(m, bits) \
597 vm_page_assert_pga_writeable(m, bits)
599 #define VM_PAGE_OBJECT_LOCK_ASSERT(m) (void)0
600 #define VM_PAGE_ASSERT_PGA_WRITEABLE(m, bits) (void)0
604 * We want to use atomic updates for the aflags field, which is 8 bits wide.
605 * However, not all architectures support atomic operations on 8-bit
606 * destinations. In order that we can easily use a 32-bit operation, we
607 * require that the aflags field be 32-bit aligned.
609 CTASSERT(offsetof(struct vm_page, aflags) % sizeof(uint32_t) == 0);
612 * Clear the given bits in the specified page.
615 vm_page_aflag_clear(vm_page_t m, uint8_t bits)
620 * The PGA_REFERENCED flag can only be cleared if the page is locked.
622 if ((bits & PGA_REFERENCED) != 0)
623 vm_page_assert_locked(m);
626 * Access the whole 32-bit word containing the aflags field with an
627 * atomic update. Parallel non-atomic updates to the other fields
628 * within this word are handled properly by the atomic update.
630 addr = (void *)&m->aflags;
631 KASSERT(((uintptr_t)addr & (sizeof(uint32_t) - 1)) == 0,
632 ("vm_page_aflag_clear: aflags is misaligned"));
634 #if BYTE_ORDER == BIG_ENDIAN
637 atomic_clear_32(addr, val);
641 * Set the given bits in the specified page.
644 vm_page_aflag_set(vm_page_t m, uint8_t bits)
648 VM_PAGE_ASSERT_PGA_WRITEABLE(m, bits);
651 * Access the whole 32-bit word containing the aflags field with an
652 * atomic update. Parallel non-atomic updates to the other fields
653 * within this word are handled properly by the atomic update.
655 addr = (void *)&m->aflags;
656 KASSERT(((uintptr_t)addr & (sizeof(uint32_t) - 1)) == 0,
657 ("vm_page_aflag_set: aflags is misaligned"));
659 #if BYTE_ORDER == BIG_ENDIAN
662 atomic_set_32(addr, val);
668 * Set all bits in the page's dirty field.
670 * The object containing the specified page must be locked if the
671 * call is made from the machine-independent layer.
673 * See vm_page_clear_dirty_mask().
676 vm_page_dirty(vm_page_t m)
679 /* Use vm_page_dirty_KBI() under INVARIANTS to save memory. */
680 #if defined(KLD_MODULE) || defined(INVARIANTS)
681 vm_page_dirty_KBI(m);
683 m->dirty = VM_PAGE_BITS_ALL;
690 * If the given page is in a page queue, then remove it from that page
693 * The page must be locked.
696 vm_page_remque(vm_page_t m)
699 if (m->queue != PQ_NONE)
706 * Set page to not be dirty. Note: does not clear pmap modify bits
709 vm_page_undirty(vm_page_t m)
712 VM_PAGE_OBJECT_LOCK_ASSERT(m);
717 vm_page_replace_checked(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex,
722 mret = vm_page_replace(mnew, object, pindex);
723 KASSERT(mret == mold,
724 ("invalid page replacement, mold=%p, mret=%p", mold, mret));
726 /* Unused if !INVARIANTS. */
732 vm_page_active(vm_page_t m)
735 return (m->queue == PQ_ACTIVE);
739 vm_page_inactive(vm_page_t m)
742 return (m->queue == PQ_INACTIVE);
746 vm_page_in_laundry(vm_page_t m)
749 return (m->queue == PQ_LAUNDRY || m->queue == PQ_UNSWAPPABLE);
755 * Return true if a reference prevents the page from being reclaimable.
758 vm_page_held(vm_page_t m)
761 return (m->hold_count > 0 || m->wire_count > 0);
765 #endif /* !_VM_PAGE_ */