2 * Copyright (c) 1991 Regents of the University of California.
4 * Copyright (c) 1998 Matthew Dillon. All Rights Reserved.
6 * This code is derived from software contributed to Berkeley by
7 * The Mach Operating System project at Carnegie-Mellon University.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * from: @(#)vm_page.c 7.4 (Berkeley) 5/7/91
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.
64 * GENERAL RULES ON VM_PAGE MANIPULATION
66 * - A page queue lock is required when adding or removing a page from a
67 * page queue regardless of other locks or the busy state of a page.
69 * * In general, no thread besides the page daemon can acquire or
70 * hold more than one page queue lock at a time.
72 * * The page daemon can acquire and hold any pair of page queue
75 * - The object lock is required when inserting or removing
76 * pages from an object (vm_page_insert() or vm_page_remove()).
81 * Resident memory management module.
84 #include <sys/cdefs.h>
85 __FBSDID("$FreeBSD$");
89 #include <sys/param.h>
90 #include <sys/systm.h>
92 #include <sys/kernel.h>
93 #include <sys/limits.h>
94 #include <sys/linker.h>
95 #include <sys/malloc.h>
97 #include <sys/msgbuf.h>
98 #include <sys/mutex.h>
100 #include <sys/rwlock.h>
101 #include <sys/sbuf.h>
103 #include <sys/sysctl.h>
104 #include <sys/vmmeter.h>
105 #include <sys/vnode.h>
109 #include <vm/vm_param.h>
110 #include <vm/vm_kern.h>
111 #include <vm/vm_object.h>
112 #include <vm/vm_page.h>
113 #include <vm/vm_pageout.h>
114 #include <vm/vm_pager.h>
115 #include <vm/vm_phys.h>
116 #include <vm/vm_radix.h>
117 #include <vm/vm_reserv.h>
118 #include <vm/vm_extern.h>
120 #include <vm/uma_int.h>
122 #include <machine/md_var.h>
125 * Associated with page of user-allocatable memory is a
129 struct vm_domain vm_dom[MAXMEMDOM];
130 struct mtx_padalign vm_page_queue_free_mtx;
132 struct mtx_padalign pa_lock[PA_LOCK_COUNT];
135 * bogus page -- for I/O to/from partially complete buffers,
136 * or for paging into sparsely invalid regions.
138 vm_page_t bogus_page;
140 vm_page_t vm_page_array;
141 long vm_page_array_size;
144 static int boot_pages = UMA_BOOT_PAGES;
145 SYSCTL_INT(_vm, OID_AUTO, boot_pages, CTLFLAG_RDTUN | CTLFLAG_NOFETCH,
147 "number of pages allocated for bootstrapping the VM system");
149 static int pa_tryrelock_restart;
150 SYSCTL_INT(_vm, OID_AUTO, tryrelock_restart, CTLFLAG_RD,
151 &pa_tryrelock_restart, 0, "Number of tryrelock restarts");
153 static TAILQ_HEAD(, vm_page) blacklist_head;
154 static int sysctl_vm_page_blacklist(SYSCTL_HANDLER_ARGS);
155 SYSCTL_PROC(_vm, OID_AUTO, page_blacklist, CTLTYPE_STRING | CTLFLAG_RD |
156 CTLFLAG_MPSAFE, NULL, 0, sysctl_vm_page_blacklist, "A", "Blacklist pages");
158 /* Is the page daemon waiting for free pages? */
159 static int vm_pageout_pages_needed;
161 static uma_zone_t fakepg_zone;
163 static void vm_page_alloc_check(vm_page_t m);
164 static void vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits);
165 static void vm_page_enqueue(uint8_t queue, vm_page_t m);
166 static void vm_page_free_wakeup(void);
167 static void vm_page_init(void *dummy);
168 static int vm_page_insert_after(vm_page_t m, vm_object_t object,
169 vm_pindex_t pindex, vm_page_t mpred);
170 static void vm_page_insert_radixdone(vm_page_t m, vm_object_t object,
172 static int vm_page_reclaim_run(int req_class, u_long npages, vm_page_t m_run,
175 SYSINIT(vm_page, SI_SUB_VM, SI_ORDER_SECOND, vm_page_init, NULL);
178 vm_page_init(void *dummy)
181 fakepg_zone = uma_zcreate("fakepg", sizeof(struct vm_page), NULL, NULL,
182 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE | UMA_ZONE_VM);
183 bogus_page = vm_page_alloc(NULL, 0, VM_ALLOC_NOOBJ |
184 VM_ALLOC_NORMAL | VM_ALLOC_WIRED);
187 /* Make sure that u_long is at least 64 bits when PAGE_SIZE is 32K. */
188 #if PAGE_SIZE == 32768
190 CTASSERT(sizeof(u_long) >= 8);
195 * Try to acquire a physical address lock while a pmap is locked. If we
196 * fail to trylock we unlock and lock the pmap directly and cache the
197 * locked pa in *locked. The caller should then restart their loop in case
198 * the virtual to physical mapping has changed.
201 vm_page_pa_tryrelock(pmap_t pmap, vm_paddr_t pa, vm_paddr_t *locked)
208 PA_LOCK_ASSERT(lockpa, MA_OWNED);
209 if (PA_LOCKPTR(pa) == PA_LOCKPTR(lockpa))
216 atomic_add_int(&pa_tryrelock_restart, 1);
225 * Sets the page size, perhaps based upon the memory
226 * size. Must be called before any use of page-size
227 * dependent functions.
230 vm_set_page_size(void)
232 if (vm_cnt.v_page_size == 0)
233 vm_cnt.v_page_size = PAGE_SIZE;
234 if (((vm_cnt.v_page_size - 1) & vm_cnt.v_page_size) != 0)
235 panic("vm_set_page_size: page size not a power of two");
239 * vm_page_blacklist_next:
241 * Find the next entry in the provided string of blacklist
242 * addresses. Entries are separated by space, comma, or newline.
243 * If an invalid integer is encountered then the rest of the
244 * string is skipped. Updates the list pointer to the next
245 * character, or NULL if the string is exhausted or invalid.
248 vm_page_blacklist_next(char **list, char *end)
253 if (list == NULL || *list == NULL)
261 * If there's no end pointer then the buffer is coming from
262 * the kenv and we know it's null-terminated.
265 end = *list + strlen(*list);
267 /* Ensure that strtoq() won't walk off the end */
269 if (*end == '\n' || *end == ' ' || *end == ',')
272 printf("Blacklist not terminated, skipping\n");
278 for (pos = *list; *pos != '\0'; pos = cp) {
279 bad = strtoq(pos, &cp, 0);
280 if (*cp == '\0' || *cp == ' ' || *cp == ',' || *cp == '\n') {
289 if (*cp == '\0' || ++cp >= end)
293 return (trunc_page(bad));
295 printf("Garbage in RAM blacklist, skipping\n");
301 * vm_page_blacklist_check:
303 * Iterate through the provided string of blacklist addresses, pulling
304 * each entry out of the physical allocator free list and putting it
305 * onto a list for reporting via the vm.page_blacklist sysctl.
308 vm_page_blacklist_check(char *list, char *end)
316 while (next != NULL) {
317 if ((pa = vm_page_blacklist_next(&next, end)) == 0)
319 m = vm_phys_paddr_to_vm_page(pa);
322 mtx_lock(&vm_page_queue_free_mtx);
323 ret = vm_phys_unfree_page(m);
324 mtx_unlock(&vm_page_queue_free_mtx);
326 TAILQ_INSERT_TAIL(&blacklist_head, m, listq);
328 printf("Skipping page with pa 0x%jx\n",
335 * vm_page_blacklist_load:
337 * Search for a special module named "ram_blacklist". It'll be a
338 * plain text file provided by the user via the loader directive
342 vm_page_blacklist_load(char **list, char **end)
351 mod = preload_search_by_type("ram_blacklist");
353 ptr = preload_fetch_addr(mod);
354 len = preload_fetch_size(mod);
365 sysctl_vm_page_blacklist(SYSCTL_HANDLER_ARGS)
372 error = sysctl_wire_old_buffer(req, 0);
375 sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
376 TAILQ_FOREACH(m, &blacklist_head, listq) {
377 sbuf_printf(&sbuf, "%s%#jx", first ? "" : ",",
378 (uintmax_t)m->phys_addr);
381 error = sbuf_finish(&sbuf);
387 vm_page_domain_init(struct vm_domain *vmd)
389 struct vm_pagequeue *pq;
392 *__DECONST(char **, &vmd->vmd_pagequeues[PQ_INACTIVE].pq_name) =
393 "vm inactive pagequeue";
394 *__DECONST(u_int **, &vmd->vmd_pagequeues[PQ_INACTIVE].pq_vcnt) =
395 &vm_cnt.v_inactive_count;
396 *__DECONST(char **, &vmd->vmd_pagequeues[PQ_ACTIVE].pq_name) =
397 "vm active pagequeue";
398 *__DECONST(u_int **, &vmd->vmd_pagequeues[PQ_ACTIVE].pq_vcnt) =
399 &vm_cnt.v_active_count;
400 *__DECONST(char **, &vmd->vmd_pagequeues[PQ_LAUNDRY].pq_name) =
401 "vm laundry pagequeue";
402 *__DECONST(int **, &vmd->vmd_pagequeues[PQ_LAUNDRY].pq_vcnt) =
403 &vm_cnt.v_laundry_count;
404 *__DECONST(char **, &vmd->vmd_pagequeues[PQ_UNSWAPPABLE].pq_name) =
405 "vm unswappable pagequeue";
406 /* Unswappable dirty pages are counted as being in the laundry. */
407 *__DECONST(int **, &vmd->vmd_pagequeues[PQ_UNSWAPPABLE].pq_vcnt) =
408 &vm_cnt.v_laundry_count;
409 vmd->vmd_page_count = 0;
410 vmd->vmd_free_count = 0;
412 vmd->vmd_oom = FALSE;
413 for (i = 0; i < PQ_COUNT; i++) {
414 pq = &vmd->vmd_pagequeues[i];
415 TAILQ_INIT(&pq->pq_pl);
416 mtx_init(&pq->pq_mutex, pq->pq_name, "vm pagequeue",
417 MTX_DEF | MTX_DUPOK);
424 * Initializes the resident memory module.
426 * Allocates memory for the page cells, and
427 * for the object/offset-to-page hash table headers.
428 * Each page cell is initialized and placed on the free list.
431 vm_page_startup(vm_offset_t vaddr)
434 vm_paddr_t page_range;
439 char *list, *listend;
441 vm_paddr_t biggestsize;
442 vm_paddr_t low_water, high_water;
448 vaddr = round_page(vaddr);
450 for (i = 0; phys_avail[i + 1]; i += 2) {
451 phys_avail[i] = round_page(phys_avail[i]);
452 phys_avail[i + 1] = trunc_page(phys_avail[i + 1]);
455 low_water = phys_avail[0];
456 high_water = phys_avail[1];
458 for (i = 0; i < vm_phys_nsegs; i++) {
459 if (vm_phys_segs[i].start < low_water)
460 low_water = vm_phys_segs[i].start;
461 if (vm_phys_segs[i].end > high_water)
462 high_water = vm_phys_segs[i].end;
464 for (i = 0; phys_avail[i + 1]; i += 2) {
465 vm_paddr_t size = phys_avail[i + 1] - phys_avail[i];
467 if (size > biggestsize) {
471 if (phys_avail[i] < low_water)
472 low_water = phys_avail[i];
473 if (phys_avail[i + 1] > high_water)
474 high_water = phys_avail[i + 1];
477 end = phys_avail[biggestone+1];
480 * Initialize the page and queue locks.
482 mtx_init(&vm_page_queue_free_mtx, "vm page free queue", NULL, MTX_DEF);
483 for (i = 0; i < PA_LOCK_COUNT; i++)
484 mtx_init(&pa_lock[i], "vm page", NULL, MTX_DEF);
485 for (i = 0; i < vm_ndomains; i++)
486 vm_page_domain_init(&vm_dom[i]);
489 * Almost all of the pages needed for boot strapping UMA are used
490 * for zone structures, so if the number of CPUs results in those
491 * structures taking more than one page each, we set aside more pages
492 * in proportion to the zone structure size.
494 pages_per_zone = howmany(sizeof(struct uma_zone) +
495 sizeof(struct uma_cache) * (mp_maxid + 1), UMA_SLAB_SIZE);
496 if (pages_per_zone > 1) {
497 /* Reserve more pages so that we don't run out. */
498 boot_pages = UMA_BOOT_PAGES_ZONES * pages_per_zone;
502 * Allocate memory for use when boot strapping the kernel memory
505 * CTFLAG_RDTUN doesn't work during the early boot process, so we must
506 * manually fetch the value.
508 TUNABLE_INT_FETCH("vm.boot_pages", &boot_pages);
509 new_end = end - (boot_pages * UMA_SLAB_SIZE);
510 new_end = trunc_page(new_end);
511 mapped = pmap_map(&vaddr, new_end, end,
512 VM_PROT_READ | VM_PROT_WRITE);
513 bzero((void *)mapped, end - new_end);
514 uma_startup((void *)mapped, boot_pages);
516 #if defined(__aarch64__) || defined(__amd64__) || defined(__arm__) || \
517 defined(__i386__) || defined(__mips__)
519 * Allocate a bitmap to indicate that a random physical page
520 * needs to be included in a minidump.
522 * The amd64 port needs this to indicate which direct map pages
523 * need to be dumped, via calls to dump_add_page()/dump_drop_page().
525 * However, i386 still needs this workspace internally within the
526 * minidump code. In theory, they are not needed on i386, but are
527 * included should the sf_buf code decide to use them.
530 for (i = 0; dump_avail[i + 1] != 0; i += 2)
531 if (dump_avail[i + 1] > last_pa)
532 last_pa = dump_avail[i + 1];
533 page_range = last_pa / PAGE_SIZE;
534 vm_page_dump_size = round_page(roundup2(page_range, NBBY) / NBBY);
535 new_end -= vm_page_dump_size;
536 vm_page_dump = (void *)(uintptr_t)pmap_map(&vaddr, new_end,
537 new_end + vm_page_dump_size, VM_PROT_READ | VM_PROT_WRITE);
538 bzero((void *)vm_page_dump, vm_page_dump_size);
542 * Request that the physical pages underlying the message buffer be
543 * included in a crash dump. Since the message buffer is accessed
544 * through the direct map, they are not automatically included.
546 pa = DMAP_TO_PHYS((vm_offset_t)msgbufp->msg_ptr);
547 last_pa = pa + round_page(msgbufsize);
548 while (pa < last_pa) {
554 * Compute the number of pages of memory that will be available for
555 * use (taking into account the overhead of a page structure per
558 first_page = low_water / PAGE_SIZE;
559 #ifdef VM_PHYSSEG_SPARSE
561 for (i = 0; i < vm_phys_nsegs; i++) {
562 page_range += atop(vm_phys_segs[i].end -
563 vm_phys_segs[i].start);
565 for (i = 0; phys_avail[i + 1] != 0; i += 2)
566 page_range += atop(phys_avail[i + 1] - phys_avail[i]);
567 #elif defined(VM_PHYSSEG_DENSE)
568 page_range = high_water / PAGE_SIZE - first_page;
570 #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined."
575 * Reserve an unmapped guard page to trap access to vm_page_array[-1].
580 * Initialize the mem entry structures now, and put them in the free
583 new_end = trunc_page(end - page_range * sizeof(struct vm_page));
584 mapped = pmap_map(&vaddr, new_end, end,
585 VM_PROT_READ | VM_PROT_WRITE);
586 vm_page_array = (vm_page_t) mapped;
587 #if VM_NRESERVLEVEL > 0
589 * Allocate memory for the reservation management system's data
592 new_end = vm_reserv_startup(&vaddr, new_end, high_water);
594 #if defined(__aarch64__) || defined(__amd64__) || defined(__mips__)
596 * pmap_map on arm64, amd64, and mips can come out of the direct-map,
597 * not kvm like i386, so the pages must be tracked for a crashdump to
598 * include this data. This includes the vm_page_array and the early
599 * UMA bootstrap pages.
601 for (pa = new_end; pa < phys_avail[biggestone + 1]; pa += PAGE_SIZE)
604 phys_avail[biggestone + 1] = new_end;
607 * Add physical memory segments corresponding to the available
610 for (i = 0; phys_avail[i + 1] != 0; i += 2)
611 vm_phys_add_seg(phys_avail[i], phys_avail[i + 1]);
614 * Clear all of the page structures
616 bzero((caddr_t) vm_page_array, page_range * sizeof(struct vm_page));
617 for (i = 0; i < page_range; i++)
618 vm_page_array[i].order = VM_NFREEORDER;
619 vm_page_array_size = page_range;
622 * Initialize the physical memory allocator.
627 * Add every available physical page that is not blacklisted to
630 vm_cnt.v_page_count = 0;
631 vm_cnt.v_free_count = 0;
632 for (i = 0; phys_avail[i + 1] != 0; i += 2) {
634 last_pa = phys_avail[i + 1];
635 while (pa < last_pa) {
636 vm_phys_add_page(pa);
641 TAILQ_INIT(&blacklist_head);
642 vm_page_blacklist_load(&list, &listend);
643 vm_page_blacklist_check(list, listend);
645 list = kern_getenv("vm.blacklist");
646 vm_page_blacklist_check(list, NULL);
649 #if VM_NRESERVLEVEL > 0
651 * Initialize the reservation management system.
659 vm_page_reference(vm_page_t m)
662 vm_page_aflag_set(m, PGA_REFERENCED);
666 * vm_page_busy_downgrade:
668 * Downgrade an exclusive busy page into a single shared busy page.
671 vm_page_busy_downgrade(vm_page_t m)
676 vm_page_assert_xbusied(m);
677 locked = mtx_owned(vm_page_lockptr(m));
681 x &= VPB_BIT_WAITERS;
682 if (x != 0 && !locked)
684 if (atomic_cmpset_rel_int(&m->busy_lock,
685 VPB_SINGLE_EXCLUSIVER | x, VPB_SHARERS_WORD(1)))
687 if (x != 0 && !locked)
700 * Return a positive value if the page is shared busied, 0 otherwise.
703 vm_page_sbusied(vm_page_t m)
708 return ((x & VPB_BIT_SHARED) != 0 && x != VPB_UNBUSIED);
714 * Shared unbusy a page.
717 vm_page_sunbusy(vm_page_t m)
721 vm_page_assert_sbusied(m);
725 if (VPB_SHARERS(x) > 1) {
726 if (atomic_cmpset_int(&m->busy_lock, x,
731 if ((x & VPB_BIT_WAITERS) == 0) {
732 KASSERT(x == VPB_SHARERS_WORD(1),
733 ("vm_page_sunbusy: invalid lock state"));
734 if (atomic_cmpset_int(&m->busy_lock,
735 VPB_SHARERS_WORD(1), VPB_UNBUSIED))
739 KASSERT(x == (VPB_SHARERS_WORD(1) | VPB_BIT_WAITERS),
740 ("vm_page_sunbusy: invalid lock state for waiters"));
743 if (!atomic_cmpset_int(&m->busy_lock, x, VPB_UNBUSIED)) {
754 * vm_page_busy_sleep:
756 * Sleep and release the page lock, using the page pointer as wchan.
757 * This is used to implement the hard-path of busying mechanism.
759 * The given page must be locked.
761 * If nonshared is true, sleep only if the page is xbusy.
764 vm_page_busy_sleep(vm_page_t m, const char *wmesg, bool nonshared)
768 vm_page_assert_locked(m);
771 if (x == VPB_UNBUSIED || (nonshared && (x & VPB_BIT_SHARED) != 0) ||
772 ((x & VPB_BIT_WAITERS) == 0 &&
773 !atomic_cmpset_int(&m->busy_lock, x, x | VPB_BIT_WAITERS))) {
777 msleep(m, vm_page_lockptr(m), PVM | PDROP, wmesg, 0);
783 * Try to shared busy a page.
784 * If the operation succeeds 1 is returned otherwise 0.
785 * The operation never sleeps.
788 vm_page_trysbusy(vm_page_t m)
794 if ((x & VPB_BIT_SHARED) == 0)
796 if (atomic_cmpset_acq_int(&m->busy_lock, x, x + VPB_ONE_SHARER))
802 vm_page_xunbusy_locked(vm_page_t m)
805 vm_page_assert_xbusied(m);
806 vm_page_assert_locked(m);
808 atomic_store_rel_int(&m->busy_lock, VPB_UNBUSIED);
809 /* There is a waiter, do wakeup() instead of vm_page_flash(). */
814 vm_page_xunbusy_maybelocked(vm_page_t m)
818 vm_page_assert_xbusied(m);
821 * Fast path for unbusy. If it succeeds, we know that there
822 * are no waiters, so we do not need a wakeup.
824 if (atomic_cmpset_rel_int(&m->busy_lock, VPB_SINGLE_EXCLUSIVER,
828 lockacq = !mtx_owned(vm_page_lockptr(m));
831 vm_page_xunbusy_locked(m);
837 * vm_page_xunbusy_hard:
839 * Called after the first try the exclusive unbusy of a page failed.
840 * It is assumed that the waiters bit is on.
843 vm_page_xunbusy_hard(vm_page_t m)
846 vm_page_assert_xbusied(m);
849 vm_page_xunbusy_locked(m);
856 * Wakeup anyone waiting for the page.
857 * The ownership bits do not change.
859 * The given page must be locked.
862 vm_page_flash(vm_page_t m)
866 vm_page_lock_assert(m, MA_OWNED);
870 if ((x & VPB_BIT_WAITERS) == 0)
872 if (atomic_cmpset_int(&m->busy_lock, x,
873 x & (~VPB_BIT_WAITERS)))
880 * Keep page from being freed by the page daemon
881 * much of the same effect as wiring, except much lower
882 * overhead and should be used only for *very* temporary
883 * holding ("wiring").
886 vm_page_hold(vm_page_t mem)
889 vm_page_lock_assert(mem, MA_OWNED);
894 vm_page_unhold(vm_page_t mem)
897 vm_page_lock_assert(mem, MA_OWNED);
898 KASSERT(mem->hold_count >= 1, ("vm_page_unhold: hold count < 0!!!"));
900 if (mem->hold_count == 0 && (mem->flags & PG_UNHOLDFREE) != 0)
901 vm_page_free_toq(mem);
905 * vm_page_unhold_pages:
907 * Unhold each of the pages that is referenced by the given array.
910 vm_page_unhold_pages(vm_page_t *ma, int count)
912 struct mtx *mtx, *new_mtx;
915 for (; count != 0; count--) {
917 * Avoid releasing and reacquiring the same page lock.
919 new_mtx = vm_page_lockptr(*ma);
920 if (mtx != new_mtx) {
934 PHYS_TO_VM_PAGE(vm_paddr_t pa)
938 #ifdef VM_PHYSSEG_SPARSE
939 m = vm_phys_paddr_to_vm_page(pa);
941 m = vm_phys_fictitious_to_vm_page(pa);
943 #elif defined(VM_PHYSSEG_DENSE)
947 if (pi >= first_page && (pi - first_page) < vm_page_array_size) {
948 m = &vm_page_array[pi - first_page];
951 return (vm_phys_fictitious_to_vm_page(pa));
953 #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined."
960 * Create a fictitious page with the specified physical address and
961 * memory attribute. The memory attribute is the only the machine-
962 * dependent aspect of a fictitious page that must be initialized.
965 vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr)
969 m = uma_zalloc(fakepg_zone, M_WAITOK | M_ZERO);
970 vm_page_initfake(m, paddr, memattr);
975 vm_page_initfake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr)
978 if ((m->flags & PG_FICTITIOUS) != 0) {
980 * The page's memattr might have changed since the
981 * previous initialization. Update the pmap to the
986 m->phys_addr = paddr;
988 /* Fictitious pages don't use "segind". */
989 m->flags = PG_FICTITIOUS;
990 /* Fictitious pages don't use "order" or "pool". */
991 m->oflags = VPO_UNMANAGED;
992 m->busy_lock = VPB_SINGLE_EXCLUSIVER;
996 pmap_page_set_memattr(m, memattr);
1002 * Release a fictitious page.
1005 vm_page_putfake(vm_page_t m)
1008 KASSERT((m->oflags & VPO_UNMANAGED) != 0, ("managed %p", m));
1009 KASSERT((m->flags & PG_FICTITIOUS) != 0,
1010 ("vm_page_putfake: bad page %p", m));
1011 uma_zfree(fakepg_zone, m);
1015 * vm_page_updatefake:
1017 * Update the given fictitious page to the specified physical address and
1021 vm_page_updatefake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr)
1024 KASSERT((m->flags & PG_FICTITIOUS) != 0,
1025 ("vm_page_updatefake: bad page %p", m));
1026 m->phys_addr = paddr;
1027 pmap_page_set_memattr(m, memattr);
1036 vm_page_free(vm_page_t m)
1039 m->flags &= ~PG_ZERO;
1040 vm_page_free_toq(m);
1044 * vm_page_free_zero:
1046 * Free a page to the zerod-pages queue
1049 vm_page_free_zero(vm_page_t m)
1052 m->flags |= PG_ZERO;
1053 vm_page_free_toq(m);
1057 * Unbusy and handle the page queueing for a page from a getpages request that
1058 * was optionally read ahead or behind.
1061 vm_page_readahead_finish(vm_page_t m)
1064 /* We shouldn't put invalid pages on queues. */
1065 KASSERT(m->valid != 0, ("%s: %p is invalid", __func__, m));
1068 * Since the page is not the actually needed one, whether it should
1069 * be activated or deactivated is not obvious. Empirical results
1070 * have shown that deactivating the page is usually the best choice,
1071 * unless the page is wanted by another thread.
1074 if ((m->busy_lock & VPB_BIT_WAITERS) != 0)
1075 vm_page_activate(m);
1077 vm_page_deactivate(m);
1083 * vm_page_sleep_if_busy:
1085 * Sleep and release the page queues lock if the page is busied.
1086 * Returns TRUE if the thread slept.
1088 * The given page must be unlocked and object containing it must
1092 vm_page_sleep_if_busy(vm_page_t m, const char *msg)
1096 vm_page_lock_assert(m, MA_NOTOWNED);
1097 VM_OBJECT_ASSERT_WLOCKED(m->object);
1099 if (vm_page_busied(m)) {
1101 * The page-specific object must be cached because page
1102 * identity can change during the sleep, causing the
1103 * re-lock of a different object.
1104 * It is assumed that a reference to the object is already
1105 * held by the callers.
1109 VM_OBJECT_WUNLOCK(obj);
1110 vm_page_busy_sleep(m, msg, false);
1111 VM_OBJECT_WLOCK(obj);
1118 * vm_page_dirty_KBI: [ internal use only ]
1120 * Set all bits in the page's dirty field.
1122 * The object containing the specified page must be locked if the
1123 * call is made from the machine-independent layer.
1125 * See vm_page_clear_dirty_mask().
1127 * This function should only be called by vm_page_dirty().
1130 vm_page_dirty_KBI(vm_page_t m)
1133 /* Refer to this operation by its public name. */
1134 KASSERT(m->valid == VM_PAGE_BITS_ALL,
1135 ("vm_page_dirty: page is invalid!"));
1136 m->dirty = VM_PAGE_BITS_ALL;
1140 * vm_page_insert: [ internal use only ]
1142 * Inserts the given mem entry into the object and object list.
1144 * The object must be locked.
1147 vm_page_insert(vm_page_t m, vm_object_t object, vm_pindex_t pindex)
1151 VM_OBJECT_ASSERT_WLOCKED(object);
1152 mpred = vm_radix_lookup_le(&object->rtree, pindex);
1153 return (vm_page_insert_after(m, object, pindex, mpred));
1157 * vm_page_insert_after:
1159 * Inserts the page "m" into the specified object at offset "pindex".
1161 * The page "mpred" must immediately precede the offset "pindex" within
1162 * the specified object.
1164 * The object must be locked.
1167 vm_page_insert_after(vm_page_t m, vm_object_t object, vm_pindex_t pindex,
1172 VM_OBJECT_ASSERT_WLOCKED(object);
1173 KASSERT(m->object == NULL,
1174 ("vm_page_insert_after: page already inserted"));
1175 if (mpred != NULL) {
1176 KASSERT(mpred->object == object,
1177 ("vm_page_insert_after: object doesn't contain mpred"));
1178 KASSERT(mpred->pindex < pindex,
1179 ("vm_page_insert_after: mpred doesn't precede pindex"));
1180 msucc = TAILQ_NEXT(mpred, listq);
1182 msucc = TAILQ_FIRST(&object->memq);
1184 KASSERT(msucc->pindex > pindex,
1185 ("vm_page_insert_after: msucc doesn't succeed pindex"));
1188 * Record the object/offset pair in this page
1194 * Now link into the object's ordered list of backed pages.
1196 if (vm_radix_insert(&object->rtree, m)) {
1201 vm_page_insert_radixdone(m, object, mpred);
1206 * vm_page_insert_radixdone:
1208 * Complete page "m" insertion into the specified object after the
1209 * radix trie hooking.
1211 * The page "mpred" must precede the offset "m->pindex" within the
1214 * The object must be locked.
1217 vm_page_insert_radixdone(vm_page_t m, vm_object_t object, vm_page_t mpred)
1220 VM_OBJECT_ASSERT_WLOCKED(object);
1221 KASSERT(object != NULL && m->object == object,
1222 ("vm_page_insert_radixdone: page %p has inconsistent object", m));
1223 if (mpred != NULL) {
1224 KASSERT(mpred->object == object,
1225 ("vm_page_insert_after: object doesn't contain mpred"));
1226 KASSERT(mpred->pindex < m->pindex,
1227 ("vm_page_insert_after: mpred doesn't precede pindex"));
1231 TAILQ_INSERT_AFTER(&object->memq, mpred, m, listq);
1233 TAILQ_INSERT_HEAD(&object->memq, m, listq);
1236 * Show that the object has one more resident page.
1238 object->resident_page_count++;
1241 * Hold the vnode until the last page is released.
1243 if (object->resident_page_count == 1 && object->type == OBJT_VNODE)
1244 vhold(object->handle);
1247 * Since we are inserting a new and possibly dirty page,
1248 * update the object's OBJ_MIGHTBEDIRTY flag.
1250 if (pmap_page_is_write_mapped(m))
1251 vm_object_set_writeable_dirty(object);
1257 * Removes the specified page from its containing object, but does not
1258 * invalidate any backing storage.
1260 * The object must be locked. The page must be locked if it is managed.
1263 vm_page_remove(vm_page_t m)
1268 if ((m->oflags & VPO_UNMANAGED) == 0)
1269 vm_page_assert_locked(m);
1270 if ((object = m->object) == NULL)
1272 VM_OBJECT_ASSERT_WLOCKED(object);
1273 if (vm_page_xbusied(m))
1274 vm_page_xunbusy_maybelocked(m);
1275 mrem = vm_radix_remove(&object->rtree, m->pindex);
1276 KASSERT(mrem == m, ("removed page %p, expected page %p", mrem, m));
1279 * Now remove from the object's list of backed pages.
1281 TAILQ_REMOVE(&object->memq, m, listq);
1284 * And show that the object has one fewer resident page.
1286 object->resident_page_count--;
1289 * The vnode may now be recycled.
1291 if (object->resident_page_count == 0 && object->type == OBJT_VNODE)
1292 vdrop(object->handle);
1300 * Returns the page associated with the object/offset
1301 * pair specified; if none is found, NULL is returned.
1303 * The object must be locked.
1306 vm_page_lookup(vm_object_t object, vm_pindex_t pindex)
1309 VM_OBJECT_ASSERT_LOCKED(object);
1310 return (vm_radix_lookup(&object->rtree, pindex));
1314 * vm_page_find_least:
1316 * Returns the page associated with the object with least pindex
1317 * greater than or equal to the parameter pindex, or NULL.
1319 * The object must be locked.
1322 vm_page_find_least(vm_object_t object, vm_pindex_t pindex)
1326 VM_OBJECT_ASSERT_LOCKED(object);
1327 if ((m = TAILQ_FIRST(&object->memq)) != NULL && m->pindex < pindex)
1328 m = vm_radix_lookup_ge(&object->rtree, pindex);
1333 * Returns the given page's successor (by pindex) within the object if it is
1334 * resident; if none is found, NULL is returned.
1336 * The object must be locked.
1339 vm_page_next(vm_page_t m)
1343 VM_OBJECT_ASSERT_LOCKED(m->object);
1344 if ((next = TAILQ_NEXT(m, listq)) != NULL) {
1345 MPASS(next->object == m->object);
1346 if (next->pindex != m->pindex + 1)
1353 * Returns the given page's predecessor (by pindex) within the object if it is
1354 * resident; if none is found, NULL is returned.
1356 * The object must be locked.
1359 vm_page_prev(vm_page_t m)
1363 VM_OBJECT_ASSERT_LOCKED(m->object);
1364 if ((prev = TAILQ_PREV(m, pglist, listq)) != NULL) {
1365 MPASS(prev->object == m->object);
1366 if (prev->pindex != m->pindex - 1)
1373 * Uses the page mnew as a replacement for an existing page at index
1374 * pindex which must be already present in the object.
1376 * The existing page must not be on a paging queue.
1379 vm_page_replace(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex)
1383 VM_OBJECT_ASSERT_WLOCKED(object);
1384 KASSERT(mnew->object == NULL,
1385 ("vm_page_replace: page already in object"));
1388 * This function mostly follows vm_page_insert() and
1389 * vm_page_remove() without the radix, object count and vnode
1390 * dance. Double check such functions for more comments.
1393 mnew->object = object;
1394 mnew->pindex = pindex;
1395 mold = vm_radix_replace(&object->rtree, mnew);
1396 KASSERT(mold->queue == PQ_NONE,
1397 ("vm_page_replace: mold is on a paging queue"));
1399 /* Keep the resident page list in sorted order. */
1400 TAILQ_INSERT_AFTER(&object->memq, mold, mnew, listq);
1401 TAILQ_REMOVE(&object->memq, mold, listq);
1403 mold->object = NULL;
1404 vm_page_xunbusy_maybelocked(mold);
1407 * The object's resident_page_count does not change because we have
1408 * swapped one page for another, but OBJ_MIGHTBEDIRTY.
1410 if (pmap_page_is_write_mapped(mnew))
1411 vm_object_set_writeable_dirty(object);
1418 * Move the given memory entry from its
1419 * current object to the specified target object/offset.
1421 * Note: swap associated with the page must be invalidated by the move. We
1422 * have to do this for several reasons: (1) we aren't freeing the
1423 * page, (2) we are dirtying the page, (3) the VM system is probably
1424 * moving the page from object A to B, and will then later move
1425 * the backing store from A to B and we can't have a conflict.
1427 * Note: we *always* dirty the page. It is necessary both for the
1428 * fact that we moved it, and because we may be invalidating
1431 * The objects must be locked.
1434 vm_page_rename(vm_page_t m, vm_object_t new_object, vm_pindex_t new_pindex)
1439 VM_OBJECT_ASSERT_WLOCKED(new_object);
1441 mpred = vm_radix_lookup_le(&new_object->rtree, new_pindex);
1442 KASSERT(mpred == NULL || mpred->pindex != new_pindex,
1443 ("vm_page_rename: pindex already renamed"));
1446 * Create a custom version of vm_page_insert() which does not depend
1447 * by m_prev and can cheat on the implementation aspects of the
1451 m->pindex = new_pindex;
1452 if (vm_radix_insert(&new_object->rtree, m)) {
1458 * The operation cannot fail anymore. The removal must happen before
1459 * the listq iterator is tainted.
1465 /* Return back to the new pindex to complete vm_page_insert(). */
1466 m->pindex = new_pindex;
1467 m->object = new_object;
1469 vm_page_insert_radixdone(m, new_object, mpred);
1477 * Allocate and return a page that is associated with the specified
1478 * object and offset pair. By default, this page is exclusive busied.
1480 * The caller must always specify an allocation class.
1482 * allocation classes:
1483 * VM_ALLOC_NORMAL normal process request
1484 * VM_ALLOC_SYSTEM system *really* needs a page
1485 * VM_ALLOC_INTERRUPT interrupt time request
1487 * optional allocation flags:
1488 * VM_ALLOC_COUNT(number) the number of additional pages that the caller
1489 * intends to allocate
1490 * VM_ALLOC_NOBUSY do not exclusive busy the page
1491 * VM_ALLOC_NODUMP do not include the page in a kernel core dump
1492 * VM_ALLOC_NOOBJ page is not associated with an object and
1493 * should not be exclusive busy
1494 * VM_ALLOC_SBUSY shared busy the allocated page
1495 * VM_ALLOC_WIRED wire the allocated page
1496 * VM_ALLOC_ZERO prefer a zeroed page
1498 * This routine may not sleep.
1501 vm_page_alloc(vm_object_t object, vm_pindex_t pindex, int req)
1504 int flags, req_class;
1506 mpred = NULL; /* XXX: pacify gcc */
1507 KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) &&
1508 (object != NULL || (req & VM_ALLOC_SBUSY) == 0) &&
1509 ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) !=
1510 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)),
1511 ("vm_page_alloc: inconsistent object(%p)/req(%x)", object, req));
1513 VM_OBJECT_ASSERT_WLOCKED(object);
1515 req_class = req & VM_ALLOC_CLASS_MASK;
1518 * The page daemon is allowed to dig deeper into the free page list.
1520 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT)
1521 req_class = VM_ALLOC_SYSTEM;
1523 if (object != NULL) {
1524 mpred = vm_radix_lookup_le(&object->rtree, pindex);
1525 KASSERT(mpred == NULL || mpred->pindex != pindex,
1526 ("vm_page_alloc: pindex already allocated"));
1530 * Allocate a page if the number of free pages exceeds the minimum
1531 * for the request class.
1533 mtx_lock(&vm_page_queue_free_mtx);
1534 if (vm_cnt.v_free_count > vm_cnt.v_free_reserved ||
1535 (req_class == VM_ALLOC_SYSTEM &&
1536 vm_cnt.v_free_count > vm_cnt.v_interrupt_free_min) ||
1537 (req_class == VM_ALLOC_INTERRUPT &&
1538 vm_cnt.v_free_count > 0)) {
1540 * Can we allocate the page from a reservation?
1542 #if VM_NRESERVLEVEL > 0
1543 if (object == NULL || (object->flags & (OBJ_COLORED |
1544 OBJ_FICTITIOUS)) != OBJ_COLORED || (m =
1545 vm_reserv_alloc_page(object, pindex, mpred)) == NULL)
1549 * If not, allocate it from the free page queues.
1551 m = vm_phys_alloc_pages(object != NULL ?
1552 VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT, 0);
1553 #if VM_NRESERVLEVEL > 0
1554 if (m == NULL && vm_reserv_reclaim_inactive()) {
1555 m = vm_phys_alloc_pages(object != NULL ?
1556 VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT,
1563 * Not allocatable, give up.
1565 mtx_unlock(&vm_page_queue_free_mtx);
1566 atomic_add_int(&vm_pageout_deficit,
1567 max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1));
1568 pagedaemon_wakeup();
1573 * At this point we had better have found a good page.
1575 KASSERT(m != NULL, ("vm_page_alloc: missing page"));
1576 vm_phys_freecnt_adj(m, -1);
1577 mtx_unlock(&vm_page_queue_free_mtx);
1578 vm_page_alloc_check(m);
1581 * Initialize the page. Only the PG_ZERO flag is inherited.
1584 if ((req & VM_ALLOC_ZERO) != 0)
1587 if ((req & VM_ALLOC_NODUMP) != 0)
1591 m->oflags = object == NULL || (object->flags & OBJ_UNMANAGED) != 0 ?
1593 m->busy_lock = VPB_UNBUSIED;
1594 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ | VM_ALLOC_SBUSY)) == 0)
1595 m->busy_lock = VPB_SINGLE_EXCLUSIVER;
1596 if ((req & VM_ALLOC_SBUSY) != 0)
1597 m->busy_lock = VPB_SHARERS_WORD(1);
1598 if (req & VM_ALLOC_WIRED) {
1600 * The page lock is not required for wiring a page until that
1601 * page is inserted into the object.
1603 atomic_add_int(&vm_cnt.v_wire_count, 1);
1608 if (object != NULL) {
1609 if (vm_page_insert_after(m, object, pindex, mpred)) {
1610 pagedaemon_wakeup();
1611 if (req & VM_ALLOC_WIRED) {
1612 atomic_subtract_int(&vm_cnt.v_wire_count, 1);
1615 KASSERT(m->object == NULL, ("page %p has object", m));
1616 m->oflags = VPO_UNMANAGED;
1617 m->busy_lock = VPB_UNBUSIED;
1618 /* Don't change PG_ZERO. */
1619 vm_page_free_toq(m);
1623 /* Ignore device objects; the pager sets "memattr" for them. */
1624 if (object->memattr != VM_MEMATTR_DEFAULT &&
1625 (object->flags & OBJ_FICTITIOUS) == 0)
1626 pmap_page_set_memattr(m, object->memattr);
1631 * Don't wakeup too often - wakeup the pageout daemon when
1632 * we would be nearly out of memory.
1634 if (vm_paging_needed())
1635 pagedaemon_wakeup();
1641 * vm_page_alloc_contig:
1643 * Allocate a contiguous set of physical pages of the given size "npages"
1644 * from the free lists. All of the physical pages must be at or above
1645 * the given physical address "low" and below the given physical address
1646 * "high". The given value "alignment" determines the alignment of the
1647 * first physical page in the set. If the given value "boundary" is
1648 * non-zero, then the set of physical pages cannot cross any physical
1649 * address boundary that is a multiple of that value. Both "alignment"
1650 * and "boundary" must be a power of two.
1652 * If the specified memory attribute, "memattr", is VM_MEMATTR_DEFAULT,
1653 * then the memory attribute setting for the physical pages is configured
1654 * to the object's memory attribute setting. Otherwise, the memory
1655 * attribute setting for the physical pages is configured to "memattr",
1656 * overriding the object's memory attribute setting. However, if the
1657 * object's memory attribute setting is not VM_MEMATTR_DEFAULT, then the
1658 * memory attribute setting for the physical pages cannot be configured
1659 * to VM_MEMATTR_DEFAULT.
1661 * The specified object may not contain fictitious pages.
1663 * The caller must always specify an allocation class.
1665 * allocation classes:
1666 * VM_ALLOC_NORMAL normal process request
1667 * VM_ALLOC_SYSTEM system *really* needs a page
1668 * VM_ALLOC_INTERRUPT interrupt time request
1670 * optional allocation flags:
1671 * VM_ALLOC_NOBUSY do not exclusive busy the page
1672 * VM_ALLOC_NODUMP do not include the page in a kernel core dump
1673 * VM_ALLOC_NOOBJ page is not associated with an object and
1674 * should not be exclusive busy
1675 * VM_ALLOC_SBUSY shared busy the allocated page
1676 * VM_ALLOC_WIRED wire the allocated page
1677 * VM_ALLOC_ZERO prefer a zeroed page
1679 * This routine may not sleep.
1682 vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req,
1683 u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment,
1684 vm_paddr_t boundary, vm_memattr_t memattr)
1686 vm_page_t m, m_ret, mpred;
1687 u_int busy_lock, flags, oflags;
1690 mpred = NULL; /* XXX: pacify gcc */
1691 KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) &&
1692 (object != NULL || (req & VM_ALLOC_SBUSY) == 0) &&
1693 ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) !=
1694 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)),
1695 ("vm_page_alloc_contig: inconsistent object(%p)/req(%x)", object,
1697 if (object != NULL) {
1698 VM_OBJECT_ASSERT_WLOCKED(object);
1699 KASSERT((object->flags & OBJ_FICTITIOUS) == 0,
1700 ("vm_page_alloc_contig: object %p has fictitious pages",
1703 KASSERT(npages > 0, ("vm_page_alloc_contig: npages is zero"));
1704 req_class = req & VM_ALLOC_CLASS_MASK;
1707 * The page daemon is allowed to dig deeper into the free page list.
1709 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT)
1710 req_class = VM_ALLOC_SYSTEM;
1712 if (object != NULL) {
1713 mpred = vm_radix_lookup_le(&object->rtree, pindex);
1714 KASSERT(mpred == NULL || mpred->pindex != pindex,
1715 ("vm_page_alloc_contig: pindex already allocated"));
1719 * Can we allocate the pages without the number of free pages falling
1720 * below the lower bound for the allocation class?
1722 mtx_lock(&vm_page_queue_free_mtx);
1723 if (vm_cnt.v_free_count >= npages + vm_cnt.v_free_reserved ||
1724 (req_class == VM_ALLOC_SYSTEM &&
1725 vm_cnt.v_free_count >= npages + vm_cnt.v_interrupt_free_min) ||
1726 (req_class == VM_ALLOC_INTERRUPT &&
1727 vm_cnt.v_free_count >= npages)) {
1729 * Can we allocate the pages from a reservation?
1731 #if VM_NRESERVLEVEL > 0
1733 if (object == NULL || (object->flags & OBJ_COLORED) == 0 ||
1734 (m_ret = vm_reserv_alloc_contig(object, pindex, npages,
1735 low, high, alignment, boundary, mpred)) == NULL)
1738 * If not, allocate them from the free page queues.
1740 m_ret = vm_phys_alloc_contig(npages, low, high,
1741 alignment, boundary);
1743 mtx_unlock(&vm_page_queue_free_mtx);
1744 atomic_add_int(&vm_pageout_deficit, npages);
1745 pagedaemon_wakeup();
1749 vm_phys_freecnt_adj(m_ret, -npages);
1751 #if VM_NRESERVLEVEL > 0
1752 if (vm_reserv_reclaim_contig(npages, low, high, alignment,
1757 mtx_unlock(&vm_page_queue_free_mtx);
1760 for (m = m_ret; m < &m_ret[npages]; m++)
1761 vm_page_alloc_check(m);
1764 * Initialize the pages. Only the PG_ZERO flag is inherited.
1767 if ((req & VM_ALLOC_ZERO) != 0)
1769 if ((req & VM_ALLOC_NODUMP) != 0)
1771 oflags = object == NULL || (object->flags & OBJ_UNMANAGED) != 0 ?
1773 busy_lock = VPB_UNBUSIED;
1774 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ | VM_ALLOC_SBUSY)) == 0)
1775 busy_lock = VPB_SINGLE_EXCLUSIVER;
1776 if ((req & VM_ALLOC_SBUSY) != 0)
1777 busy_lock = VPB_SHARERS_WORD(1);
1778 if ((req & VM_ALLOC_WIRED) != 0)
1779 atomic_add_int(&vm_cnt.v_wire_count, npages);
1780 if (object != NULL) {
1781 if (object->memattr != VM_MEMATTR_DEFAULT &&
1782 memattr == VM_MEMATTR_DEFAULT)
1783 memattr = object->memattr;
1785 for (m = m_ret; m < &m_ret[npages]; m++) {
1787 m->flags = (m->flags | PG_NODUMP) & flags;
1788 m->busy_lock = busy_lock;
1789 if ((req & VM_ALLOC_WIRED) != 0)
1793 if (object != NULL) {
1794 if (vm_page_insert_after(m, object, pindex, mpred)) {
1795 pagedaemon_wakeup();
1796 if ((req & VM_ALLOC_WIRED) != 0)
1797 atomic_subtract_int(
1798 &vm_cnt.v_wire_count, npages);
1799 KASSERT(m->object == NULL,
1800 ("page %p has object", m));
1802 for (m = m_ret; m < &m_ret[npages]; m++) {
1804 (req & VM_ALLOC_WIRED) != 0)
1806 m->oflags = VPO_UNMANAGED;
1807 m->busy_lock = VPB_UNBUSIED;
1808 /* Don't change PG_ZERO. */
1809 vm_page_free_toq(m);
1816 if (memattr != VM_MEMATTR_DEFAULT)
1817 pmap_page_set_memattr(m, memattr);
1820 if (vm_paging_needed())
1821 pagedaemon_wakeup();
1826 * Check a page that has been freshly dequeued from a freelist.
1829 vm_page_alloc_check(vm_page_t m)
1832 KASSERT(m->object == NULL, ("page %p has object", m));
1833 KASSERT(m->queue == PQ_NONE,
1834 ("page %p has unexpected queue %d", m, m->queue));
1835 KASSERT(m->wire_count == 0, ("page %p is wired", m));
1836 KASSERT(m->hold_count == 0, ("page %p is held", m));
1837 KASSERT(!vm_page_busied(m), ("page %p is busy", m));
1838 KASSERT(m->dirty == 0, ("page %p is dirty", m));
1839 KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT,
1840 ("page %p has unexpected memattr %d",
1841 m, pmap_page_get_memattr(m)));
1842 KASSERT(m->valid == 0, ("free page %p is valid", m));
1846 * vm_page_alloc_freelist:
1848 * Allocate a physical page from the specified free page list.
1850 * The caller must always specify an allocation class.
1852 * allocation classes:
1853 * VM_ALLOC_NORMAL normal process request
1854 * VM_ALLOC_SYSTEM system *really* needs a page
1855 * VM_ALLOC_INTERRUPT interrupt time request
1857 * optional allocation flags:
1858 * VM_ALLOC_COUNT(number) the number of additional pages that the caller
1859 * intends to allocate
1860 * VM_ALLOC_WIRED wire the allocated page
1861 * VM_ALLOC_ZERO prefer a zeroed page
1863 * This routine may not sleep.
1866 vm_page_alloc_freelist(int flind, int req)
1872 req_class = req & VM_ALLOC_CLASS_MASK;
1875 * The page daemon is allowed to dig deeper into the free page list.
1877 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT)
1878 req_class = VM_ALLOC_SYSTEM;
1881 * Do not allocate reserved pages unless the req has asked for it.
1883 mtx_lock(&vm_page_queue_free_mtx);
1884 if (vm_cnt.v_free_count > vm_cnt.v_free_reserved ||
1885 (req_class == VM_ALLOC_SYSTEM &&
1886 vm_cnt.v_free_count > vm_cnt.v_interrupt_free_min) ||
1887 (req_class == VM_ALLOC_INTERRUPT &&
1888 vm_cnt.v_free_count > 0))
1889 m = vm_phys_alloc_freelist_pages(flind, VM_FREEPOOL_DIRECT, 0);
1891 mtx_unlock(&vm_page_queue_free_mtx);
1892 atomic_add_int(&vm_pageout_deficit,
1893 max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1));
1894 pagedaemon_wakeup();
1898 mtx_unlock(&vm_page_queue_free_mtx);
1901 vm_phys_freecnt_adj(m, -1);
1902 mtx_unlock(&vm_page_queue_free_mtx);
1903 vm_page_alloc_check(m);
1906 * Initialize the page. Only the PG_ZERO flag is inherited.
1910 if ((req & VM_ALLOC_ZERO) != 0)
1913 if ((req & VM_ALLOC_WIRED) != 0) {
1915 * The page lock is not required for wiring a page that does
1916 * not belong to an object.
1918 atomic_add_int(&vm_cnt.v_wire_count, 1);
1921 /* Unmanaged pages don't use "act_count". */
1922 m->oflags = VPO_UNMANAGED;
1923 if (vm_paging_needed())
1924 pagedaemon_wakeup();
1928 #define VPSC_ANY 0 /* No restrictions. */
1929 #define VPSC_NORESERV 1 /* Skip reservations; implies VPSC_NOSUPER. */
1930 #define VPSC_NOSUPER 2 /* Skip superpages. */
1933 * vm_page_scan_contig:
1935 * Scan vm_page_array[] between the specified entries "m_start" and
1936 * "m_end" for a run of contiguous physical pages that satisfy the
1937 * specified conditions, and return the lowest page in the run. The
1938 * specified "alignment" determines the alignment of the lowest physical
1939 * page in the run. If the specified "boundary" is non-zero, then the
1940 * run of physical pages cannot span a physical address that is a
1941 * multiple of "boundary".
1943 * "m_end" is never dereferenced, so it need not point to a vm_page
1944 * structure within vm_page_array[].
1946 * "npages" must be greater than zero. "m_start" and "m_end" must not
1947 * span a hole (or discontiguity) in the physical address space. Both
1948 * "alignment" and "boundary" must be a power of two.
1951 vm_page_scan_contig(u_long npages, vm_page_t m_start, vm_page_t m_end,
1952 u_long alignment, vm_paddr_t boundary, int options)
1954 struct mtx *m_mtx, *new_mtx;
1958 #if VM_NRESERVLEVEL > 0
1961 int m_inc, order, run_ext, run_len;
1963 KASSERT(npages > 0, ("npages is 0"));
1964 KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
1965 KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
1969 for (m = m_start; m < m_end && run_len < npages; m += m_inc) {
1970 KASSERT((m->flags & (PG_FICTITIOUS | PG_MARKER)) == 0,
1971 ("page %p is PG_FICTITIOUS or PG_MARKER", m));
1974 * If the current page would be the start of a run, check its
1975 * physical address against the end, alignment, and boundary
1976 * conditions. If it doesn't satisfy these conditions, either
1977 * terminate the scan or advance to the next page that
1978 * satisfies the failed condition.
1981 KASSERT(m_run == NULL, ("m_run != NULL"));
1982 if (m + npages > m_end)
1984 pa = VM_PAGE_TO_PHYS(m);
1985 if ((pa & (alignment - 1)) != 0) {
1986 m_inc = atop(roundup2(pa, alignment) - pa);
1989 if (rounddown2(pa ^ (pa + ptoa(npages) - 1),
1991 m_inc = atop(roundup2(pa, boundary) - pa);
1995 KASSERT(m_run != NULL, ("m_run == NULL"));
1998 * Avoid releasing and reacquiring the same page lock.
2000 new_mtx = vm_page_lockptr(m);
2001 if (m_mtx != new_mtx) {
2009 if (m->wire_count != 0 || m->hold_count != 0)
2011 #if VM_NRESERVLEVEL > 0
2012 else if ((level = vm_reserv_level(m)) >= 0 &&
2013 (options & VPSC_NORESERV) != 0) {
2015 /* Advance to the end of the reservation. */
2016 pa = VM_PAGE_TO_PHYS(m);
2017 m_inc = atop(roundup2(pa + 1, vm_reserv_size(level)) -
2021 else if ((object = m->object) != NULL) {
2023 * The page is considered eligible for relocation if
2024 * and only if it could be laundered or reclaimed by
2027 if (!VM_OBJECT_TRYRLOCK(object)) {
2029 VM_OBJECT_RLOCK(object);
2031 if (m->object != object) {
2033 * The page may have been freed.
2035 VM_OBJECT_RUNLOCK(object);
2037 } else if (m->wire_count != 0 ||
2038 m->hold_count != 0) {
2043 KASSERT((m->flags & PG_UNHOLDFREE) == 0,
2044 ("page %p is PG_UNHOLDFREE", m));
2045 /* Don't care: PG_NODUMP, PG_ZERO. */
2046 if (object->type != OBJT_DEFAULT &&
2047 object->type != OBJT_SWAP &&
2048 object->type != OBJT_VNODE) {
2050 #if VM_NRESERVLEVEL > 0
2051 } else if ((options & VPSC_NOSUPER) != 0 &&
2052 (level = vm_reserv_level_iffullpop(m)) >= 0) {
2054 /* Advance to the end of the superpage. */
2055 pa = VM_PAGE_TO_PHYS(m);
2056 m_inc = atop(roundup2(pa + 1,
2057 vm_reserv_size(level)) - pa);
2059 } else if (object->memattr == VM_MEMATTR_DEFAULT &&
2060 m->queue != PQ_NONE && !vm_page_busied(m)) {
2062 * The page is allocated but eligible for
2063 * relocation. Extend the current run by one
2066 KASSERT(pmap_page_get_memattr(m) ==
2068 ("page %p has an unexpected memattr", m));
2069 KASSERT((m->oflags & (VPO_SWAPINPROG |
2070 VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0,
2071 ("page %p has unexpected oflags", m));
2072 /* Don't care: VPO_NOSYNC. */
2077 VM_OBJECT_RUNLOCK(object);
2078 #if VM_NRESERVLEVEL > 0
2079 } else if (level >= 0) {
2081 * The page is reserved but not yet allocated. In
2082 * other words, it is still free. Extend the current
2087 } else if ((order = m->order) < VM_NFREEORDER) {
2089 * The page is enqueued in the physical memory
2090 * allocator's free page queues. Moreover, it is the
2091 * first page in a power-of-two-sized run of
2092 * contiguous free pages. Add these pages to the end
2093 * of the current run, and jump ahead.
2095 run_ext = 1 << order;
2099 * Skip the page for one of the following reasons: (1)
2100 * It is enqueued in the physical memory allocator's
2101 * free page queues. However, it is not the first
2102 * page in a run of contiguous free pages. (This case
2103 * rarely occurs because the scan is performed in
2104 * ascending order.) (2) It is not reserved, and it is
2105 * transitioning from free to allocated. (Conversely,
2106 * the transition from allocated to free for managed
2107 * pages is blocked by the page lock.) (3) It is
2108 * allocated but not contained by an object and not
2109 * wired, e.g., allocated by Xen's balloon driver.
2115 * Extend or reset the current run of pages.
2130 if (run_len >= npages)
2136 * vm_page_reclaim_run:
2138 * Try to relocate each of the allocated virtual pages within the
2139 * specified run of physical pages to a new physical address. Free the
2140 * physical pages underlying the relocated virtual pages. A virtual page
2141 * is relocatable if and only if it could be laundered or reclaimed by
2142 * the page daemon. Whenever possible, a virtual page is relocated to a
2143 * physical address above "high".
2145 * Returns 0 if every physical page within the run was already free or
2146 * just freed by a successful relocation. Otherwise, returns a non-zero
2147 * value indicating why the last attempt to relocate a virtual page was
2150 * "req_class" must be an allocation class.
2153 vm_page_reclaim_run(int req_class, u_long npages, vm_page_t m_run,
2156 struct mtx *m_mtx, *new_mtx;
2157 struct spglist free;
2160 vm_page_t m, m_end, m_new;
2161 int error, order, req;
2163 KASSERT((req_class & VM_ALLOC_CLASS_MASK) == req_class,
2164 ("req_class is not an allocation class"));
2168 m_end = m_run + npages;
2170 for (; error == 0 && m < m_end; m++) {
2171 KASSERT((m->flags & (PG_FICTITIOUS | PG_MARKER)) == 0,
2172 ("page %p is PG_FICTITIOUS or PG_MARKER", m));
2175 * Avoid releasing and reacquiring the same page lock.
2177 new_mtx = vm_page_lockptr(m);
2178 if (m_mtx != new_mtx) {
2185 if (m->wire_count != 0 || m->hold_count != 0)
2187 else if ((object = m->object) != NULL) {
2189 * The page is relocated if and only if it could be
2190 * laundered or reclaimed by the page daemon.
2192 if (!VM_OBJECT_TRYWLOCK(object)) {
2194 VM_OBJECT_WLOCK(object);
2196 if (m->object != object) {
2198 * The page may have been freed.
2200 VM_OBJECT_WUNLOCK(object);
2202 } else if (m->wire_count != 0 ||
2203 m->hold_count != 0) {
2208 KASSERT((m->flags & PG_UNHOLDFREE) == 0,
2209 ("page %p is PG_UNHOLDFREE", m));
2210 /* Don't care: PG_NODUMP, PG_ZERO. */
2211 if (object->type != OBJT_DEFAULT &&
2212 object->type != OBJT_SWAP &&
2213 object->type != OBJT_VNODE)
2215 else if (object->memattr != VM_MEMATTR_DEFAULT)
2217 else if (m->queue != PQ_NONE && !vm_page_busied(m)) {
2218 KASSERT(pmap_page_get_memattr(m) ==
2220 ("page %p has an unexpected memattr", m));
2221 KASSERT((m->oflags & (VPO_SWAPINPROG |
2222 VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0,
2223 ("page %p has unexpected oflags", m));
2224 /* Don't care: VPO_NOSYNC. */
2225 if (m->valid != 0) {
2227 * First, try to allocate a new page
2228 * that is above "high". Failing
2229 * that, try to allocate a new page
2230 * that is below "m_run". Allocate
2231 * the new page between the end of
2232 * "m_run" and "high" only as a last
2235 req = req_class | VM_ALLOC_NOOBJ;
2236 if ((m->flags & PG_NODUMP) != 0)
2237 req |= VM_ALLOC_NODUMP;
2238 if (trunc_page(high) !=
2239 ~(vm_paddr_t)PAGE_MASK) {
2240 m_new = vm_page_alloc_contig(
2245 VM_MEMATTR_DEFAULT);
2248 if (m_new == NULL) {
2249 pa = VM_PAGE_TO_PHYS(m_run);
2250 m_new = vm_page_alloc_contig(
2252 0, pa - 1, PAGE_SIZE, 0,
2253 VM_MEMATTR_DEFAULT);
2255 if (m_new == NULL) {
2257 m_new = vm_page_alloc_contig(
2259 pa, high, PAGE_SIZE, 0,
2260 VM_MEMATTR_DEFAULT);
2262 if (m_new == NULL) {
2266 KASSERT(m_new->wire_count == 0,
2267 ("page %p is wired", m));
2270 * Replace "m" with the new page. For
2271 * vm_page_replace(), "m" must be busy
2272 * and dequeued. Finally, change "m"
2273 * as if vm_page_free() was called.
2275 if (object->ref_count != 0)
2277 m_new->aflags = m->aflags;
2278 KASSERT(m_new->oflags == VPO_UNMANAGED,
2279 ("page %p is managed", m));
2280 m_new->oflags = m->oflags & VPO_NOSYNC;
2281 pmap_copy_page(m, m_new);
2282 m_new->valid = m->valid;
2283 m_new->dirty = m->dirty;
2284 m->flags &= ~PG_ZERO;
2287 vm_page_replace_checked(m_new, object,
2293 * The new page must be deactivated
2294 * before the object is unlocked.
2296 new_mtx = vm_page_lockptr(m_new);
2297 if (m_mtx != new_mtx) {
2302 vm_page_deactivate(m_new);
2304 m->flags &= ~PG_ZERO;
2307 KASSERT(m->dirty == 0,
2308 ("page %p is dirty", m));
2310 SLIST_INSERT_HEAD(&free, m, plinks.s.ss);
2314 VM_OBJECT_WUNLOCK(object);
2316 mtx_lock(&vm_page_queue_free_mtx);
2318 if (order < VM_NFREEORDER) {
2320 * The page is enqueued in the physical memory
2321 * allocator's free page queues. Moreover, it
2322 * is the first page in a power-of-two-sized
2323 * run of contiguous free pages. Jump ahead
2324 * to the last page within that run, and
2325 * continue from there.
2327 m += (1 << order) - 1;
2329 #if VM_NRESERVLEVEL > 0
2330 else if (vm_reserv_is_page_free(m))
2333 mtx_unlock(&vm_page_queue_free_mtx);
2334 if (order == VM_NFREEORDER)
2340 if ((m = SLIST_FIRST(&free)) != NULL) {
2341 mtx_lock(&vm_page_queue_free_mtx);
2343 SLIST_REMOVE_HEAD(&free, plinks.s.ss);
2344 vm_phys_freecnt_adj(m, 1);
2345 #if VM_NRESERVLEVEL > 0
2346 if (!vm_reserv_free_page(m))
2350 vm_phys_free_pages(m, 0);
2351 } while ((m = SLIST_FIRST(&free)) != NULL);
2352 vm_page_free_wakeup();
2353 mtx_unlock(&vm_page_queue_free_mtx);
2360 CTASSERT(powerof2(NRUNS));
2362 #define RUN_INDEX(count) ((count) & (NRUNS - 1))
2364 #define MIN_RECLAIM 8
2367 * vm_page_reclaim_contig:
2369 * Reclaim allocated, contiguous physical memory satisfying the specified
2370 * conditions by relocating the virtual pages using that physical memory.
2371 * Returns true if reclamation is successful and false otherwise. Since
2372 * relocation requires the allocation of physical pages, reclamation may
2373 * fail due to a shortage of free pages. When reclamation fails, callers
2374 * are expected to perform VM_WAIT before retrying a failed allocation
2375 * operation, e.g., vm_page_alloc_contig().
2377 * The caller must always specify an allocation class through "req".
2379 * allocation classes:
2380 * VM_ALLOC_NORMAL normal process request
2381 * VM_ALLOC_SYSTEM system *really* needs a page
2382 * VM_ALLOC_INTERRUPT interrupt time request
2384 * The optional allocation flags are ignored.
2386 * "npages" must be greater than zero. Both "alignment" and "boundary"
2387 * must be a power of two.
2390 vm_page_reclaim_contig(int req, u_long npages, vm_paddr_t low, vm_paddr_t high,
2391 u_long alignment, vm_paddr_t boundary)
2393 vm_paddr_t curr_low;
2394 vm_page_t m_run, m_runs[NRUNS];
2395 u_long count, reclaimed;
2396 int error, i, options, req_class;
2398 KASSERT(npages > 0, ("npages is 0"));
2399 KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
2400 KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
2401 req_class = req & VM_ALLOC_CLASS_MASK;
2404 * The page daemon is allowed to dig deeper into the free page list.
2406 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT)
2407 req_class = VM_ALLOC_SYSTEM;
2410 * Return if the number of free pages cannot satisfy the requested
2413 count = vm_cnt.v_free_count;
2414 if (count < npages + vm_cnt.v_free_reserved || (count < npages +
2415 vm_cnt.v_interrupt_free_min && req_class == VM_ALLOC_SYSTEM) ||
2416 (count < npages && req_class == VM_ALLOC_INTERRUPT))
2420 * Scan up to three times, relaxing the restrictions ("options") on
2421 * the reclamation of reservations and superpages each time.
2423 for (options = VPSC_NORESERV;;) {
2425 * Find the highest runs that satisfy the given constraints
2426 * and restrictions, and record them in "m_runs".
2431 m_run = vm_phys_scan_contig(npages, curr_low, high,
2432 alignment, boundary, options);
2435 curr_low = VM_PAGE_TO_PHYS(m_run) + ptoa(npages);
2436 m_runs[RUN_INDEX(count)] = m_run;
2441 * Reclaim the highest runs in LIFO (descending) order until
2442 * the number of reclaimed pages, "reclaimed", is at least
2443 * MIN_RECLAIM. Reset "reclaimed" each time because each
2444 * reclamation is idempotent, and runs will (likely) recur
2445 * from one scan to the next as restrictions are relaxed.
2448 for (i = 0; count > 0 && i < NRUNS; i++) {
2450 m_run = m_runs[RUN_INDEX(count)];
2451 error = vm_page_reclaim_run(req_class, npages, m_run,
2454 reclaimed += npages;
2455 if (reclaimed >= MIN_RECLAIM)
2461 * Either relax the restrictions on the next scan or return if
2462 * the last scan had no restrictions.
2464 if (options == VPSC_NORESERV)
2465 options = VPSC_NOSUPER;
2466 else if (options == VPSC_NOSUPER)
2468 else if (options == VPSC_ANY)
2469 return (reclaimed != 0);
2474 * vm_wait: (also see VM_WAIT macro)
2476 * Sleep until free pages are available for allocation.
2477 * - Called in various places before memory allocations.
2483 mtx_lock(&vm_page_queue_free_mtx);
2484 if (curproc == pageproc) {
2485 vm_pageout_pages_needed = 1;
2486 msleep(&vm_pageout_pages_needed, &vm_page_queue_free_mtx,
2487 PDROP | PSWP, "VMWait", 0);
2489 if (__predict_false(pageproc == NULL))
2490 panic("vm_wait in early boot");
2491 if (!vm_pageout_wanted) {
2492 vm_pageout_wanted = true;
2493 wakeup(&vm_pageout_wanted);
2495 vm_pages_needed = true;
2496 msleep(&vm_cnt.v_free_count, &vm_page_queue_free_mtx, PDROP | PVM,
2502 * vm_waitpfault: (also see VM_WAITPFAULT macro)
2504 * Sleep until free pages are available for allocation.
2505 * - Called only in vm_fault so that processes page faulting
2506 * can be easily tracked.
2507 * - Sleeps at a lower priority than vm_wait() so that vm_wait()ing
2508 * processes will be able to grab memory first. Do not change
2509 * this balance without careful testing first.
2515 mtx_lock(&vm_page_queue_free_mtx);
2516 if (!vm_pageout_wanted) {
2517 vm_pageout_wanted = true;
2518 wakeup(&vm_pageout_wanted);
2520 vm_pages_needed = true;
2521 msleep(&vm_cnt.v_free_count, &vm_page_queue_free_mtx, PDROP | PUSER,
2525 struct vm_pagequeue *
2526 vm_page_pagequeue(vm_page_t m)
2529 if (vm_page_in_laundry(m))
2530 return (&vm_dom[0].vmd_pagequeues[m->queue]);
2532 return (&vm_phys_domain(m)->vmd_pagequeues[m->queue]);
2538 * Remove the given page from its current page queue.
2540 * The page must be locked.
2543 vm_page_dequeue(vm_page_t m)
2545 struct vm_pagequeue *pq;
2547 vm_page_assert_locked(m);
2548 KASSERT(m->queue < PQ_COUNT, ("vm_page_dequeue: page %p is not queued",
2550 pq = vm_page_pagequeue(m);
2551 vm_pagequeue_lock(pq);
2553 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q);
2554 vm_pagequeue_cnt_dec(pq);
2555 vm_pagequeue_unlock(pq);
2559 * vm_page_dequeue_locked:
2561 * Remove the given page from its current page queue.
2563 * The page and page queue must be locked.
2566 vm_page_dequeue_locked(vm_page_t m)
2568 struct vm_pagequeue *pq;
2570 vm_page_lock_assert(m, MA_OWNED);
2571 pq = vm_page_pagequeue(m);
2572 vm_pagequeue_assert_locked(pq);
2574 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q);
2575 vm_pagequeue_cnt_dec(pq);
2581 * Add the given page to the specified page queue.
2583 * The page must be locked.
2586 vm_page_enqueue(uint8_t queue, vm_page_t m)
2588 struct vm_pagequeue *pq;
2590 vm_page_lock_assert(m, MA_OWNED);
2591 KASSERT(queue < PQ_COUNT,
2592 ("vm_page_enqueue: invalid queue %u request for page %p",
2594 if (queue == PQ_LAUNDRY || queue == PQ_UNSWAPPABLE)
2595 pq = &vm_dom[0].vmd_pagequeues[queue];
2597 pq = &vm_phys_domain(m)->vmd_pagequeues[queue];
2598 vm_pagequeue_lock(pq);
2600 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q);
2601 vm_pagequeue_cnt_inc(pq);
2602 vm_pagequeue_unlock(pq);
2608 * Move the given page to the tail of its current page queue.
2610 * The page must be locked.
2613 vm_page_requeue(vm_page_t m)
2615 struct vm_pagequeue *pq;
2617 vm_page_lock_assert(m, MA_OWNED);
2618 KASSERT(m->queue != PQ_NONE,
2619 ("vm_page_requeue: page %p is not queued", m));
2620 pq = vm_page_pagequeue(m);
2621 vm_pagequeue_lock(pq);
2622 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q);
2623 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q);
2624 vm_pagequeue_unlock(pq);
2628 * vm_page_requeue_locked:
2630 * Move the given page to the tail of its current page queue.
2632 * The page queue must be locked.
2635 vm_page_requeue_locked(vm_page_t m)
2637 struct vm_pagequeue *pq;
2639 KASSERT(m->queue != PQ_NONE,
2640 ("vm_page_requeue_locked: page %p is not queued", m));
2641 pq = vm_page_pagequeue(m);
2642 vm_pagequeue_assert_locked(pq);
2643 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q);
2644 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q);
2650 * Put the specified page on the active list (if appropriate).
2651 * Ensure that act_count is at least ACT_INIT but do not otherwise
2654 * The page must be locked.
2657 vm_page_activate(vm_page_t m)
2661 vm_page_lock_assert(m, MA_OWNED);
2662 if ((queue = m->queue) != PQ_ACTIVE) {
2663 if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) {
2664 if (m->act_count < ACT_INIT)
2665 m->act_count = ACT_INIT;
2666 if (queue != PQ_NONE)
2668 vm_page_enqueue(PQ_ACTIVE, m);
2670 KASSERT(queue == PQ_NONE,
2671 ("vm_page_activate: wired page %p is queued", m));
2673 if (m->act_count < ACT_INIT)
2674 m->act_count = ACT_INIT;
2679 * vm_page_free_wakeup:
2681 * Helper routine for vm_page_free_toq(). This routine is called
2682 * when a page is added to the free queues.
2684 * The page queues must be locked.
2687 vm_page_free_wakeup(void)
2690 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
2692 * if pageout daemon needs pages, then tell it that there are
2695 if (vm_pageout_pages_needed &&
2696 vm_cnt.v_free_count >= vm_cnt.v_pageout_free_min) {
2697 wakeup(&vm_pageout_pages_needed);
2698 vm_pageout_pages_needed = 0;
2701 * wakeup processes that are waiting on memory if we hit a
2702 * high water mark. And wakeup scheduler process if we have
2703 * lots of memory. this process will swapin processes.
2705 if (vm_pages_needed && !vm_page_count_min()) {
2706 vm_pages_needed = false;
2707 wakeup(&vm_cnt.v_free_count);
2714 * Returns the given page to the free list,
2715 * disassociating it with any VM object.
2717 * The object must be locked. The page must be locked if it is managed.
2720 vm_page_free_toq(vm_page_t m)
2723 if ((m->oflags & VPO_UNMANAGED) == 0) {
2724 vm_page_lock_assert(m, MA_OWNED);
2725 KASSERT(!pmap_page_is_mapped(m),
2726 ("vm_page_free_toq: freeing mapped page %p", m));
2728 KASSERT(m->queue == PQ_NONE,
2729 ("vm_page_free_toq: unmanaged page %p is queued", m));
2730 PCPU_INC(cnt.v_tfree);
2732 if (vm_page_sbusied(m))
2733 panic("vm_page_free: freeing busy page %p", m);
2736 * Unqueue, then remove page. Note that we cannot destroy
2737 * the page here because we do not want to call the pager's
2738 * callback routine until after we've put the page on the
2739 * appropriate free queue.
2745 * If fictitious remove object association and
2746 * return, otherwise delay object association removal.
2748 if ((m->flags & PG_FICTITIOUS) != 0) {
2755 if (m->wire_count != 0)
2756 panic("vm_page_free: freeing wired page %p", m);
2757 if (m->hold_count != 0) {
2758 m->flags &= ~PG_ZERO;
2759 KASSERT((m->flags & PG_UNHOLDFREE) == 0,
2760 ("vm_page_free: freeing PG_UNHOLDFREE page %p", m));
2761 m->flags |= PG_UNHOLDFREE;
2764 * Restore the default memory attribute to the page.
2766 if (pmap_page_get_memattr(m) != VM_MEMATTR_DEFAULT)
2767 pmap_page_set_memattr(m, VM_MEMATTR_DEFAULT);
2770 * Insert the page into the physical memory allocator's free
2773 mtx_lock(&vm_page_queue_free_mtx);
2774 vm_phys_freecnt_adj(m, 1);
2775 #if VM_NRESERVLEVEL > 0
2776 if (!vm_reserv_free_page(m))
2780 vm_phys_free_pages(m, 0);
2781 vm_page_free_wakeup();
2782 mtx_unlock(&vm_page_queue_free_mtx);
2789 * Mark this page as wired down by yet
2790 * another map, removing it from paging queues
2793 * If the page is fictitious, then its wire count must remain one.
2795 * The page must be locked.
2798 vm_page_wire(vm_page_t m)
2802 * Only bump the wire statistics if the page is not already wired,
2803 * and only unqueue the page if it is on some queue (if it is unmanaged
2804 * it is already off the queues).
2806 vm_page_lock_assert(m, MA_OWNED);
2807 if ((m->flags & PG_FICTITIOUS) != 0) {
2808 KASSERT(m->wire_count == 1,
2809 ("vm_page_wire: fictitious page %p's wire count isn't one",
2813 if (m->wire_count == 0) {
2814 KASSERT((m->oflags & VPO_UNMANAGED) == 0 ||
2815 m->queue == PQ_NONE,
2816 ("vm_page_wire: unmanaged page %p is queued", m));
2818 atomic_add_int(&vm_cnt.v_wire_count, 1);
2821 KASSERT(m->wire_count != 0, ("vm_page_wire: wire_count overflow m=%p", m));
2827 * Release one wiring of the specified page, potentially allowing it to be
2828 * paged out. Returns TRUE if the number of wirings transitions to zero and
2831 * Only managed pages belonging to an object can be paged out. If the number
2832 * of wirings transitions to zero and the page is eligible for page out, then
2833 * the page is added to the specified paging queue (unless PQ_NONE is
2836 * If a page is fictitious, then its wire count must always be one.
2838 * A managed page must be locked.
2841 vm_page_unwire(vm_page_t m, uint8_t queue)
2844 KASSERT(queue < PQ_COUNT || queue == PQ_NONE,
2845 ("vm_page_unwire: invalid queue %u request for page %p",
2847 if ((m->oflags & VPO_UNMANAGED) == 0)
2848 vm_page_assert_locked(m);
2849 if ((m->flags & PG_FICTITIOUS) != 0) {
2850 KASSERT(m->wire_count == 1,
2851 ("vm_page_unwire: fictitious page %p's wire count isn't one", m));
2854 if (m->wire_count > 0) {
2856 if (m->wire_count == 0) {
2857 atomic_subtract_int(&vm_cnt.v_wire_count, 1);
2858 if ((m->oflags & VPO_UNMANAGED) == 0 &&
2859 m->object != NULL && queue != PQ_NONE)
2860 vm_page_enqueue(queue, m);
2865 panic("vm_page_unwire: page %p's wire count is zero", m);
2869 * Move the specified page to the inactive queue.
2871 * Normally, "noreuse" is FALSE, resulting in LRU ordering of the inactive
2872 * queue. However, setting "noreuse" to TRUE will accelerate the specified
2873 * page's reclamation, but it will not unmap the page from any address space.
2874 * This is implemented by inserting the page near the head of the inactive
2875 * queue, using a marker page to guide FIFO insertion ordering.
2877 * The page must be locked.
2880 _vm_page_deactivate(vm_page_t m, boolean_t noreuse)
2882 struct vm_pagequeue *pq;
2885 vm_page_assert_locked(m);
2888 * Ignore if the page is already inactive, unless it is unlikely to be
2891 if ((queue = m->queue) == PQ_INACTIVE && !noreuse)
2893 if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) {
2894 pq = &vm_phys_domain(m)->vmd_pagequeues[PQ_INACTIVE];
2895 /* Avoid multiple acquisitions of the inactive queue lock. */
2896 if (queue == PQ_INACTIVE) {
2897 vm_pagequeue_lock(pq);
2898 vm_page_dequeue_locked(m);
2900 if (queue != PQ_NONE)
2902 vm_pagequeue_lock(pq);
2904 m->queue = PQ_INACTIVE;
2906 TAILQ_INSERT_BEFORE(&vm_phys_domain(m)->vmd_inacthead,
2909 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q);
2910 vm_pagequeue_cnt_inc(pq);
2911 vm_pagequeue_unlock(pq);
2916 * Move the specified page to the inactive queue.
2918 * The page must be locked.
2921 vm_page_deactivate(vm_page_t m)
2924 _vm_page_deactivate(m, FALSE);
2928 * Move the specified page to the inactive queue with the expectation
2929 * that it is unlikely to be reused.
2931 * The page must be locked.
2934 vm_page_deactivate_noreuse(vm_page_t m)
2937 _vm_page_deactivate(m, TRUE);
2943 * Put a page in the laundry.
2946 vm_page_launder(vm_page_t m)
2950 vm_page_assert_locked(m);
2951 if ((queue = m->queue) != PQ_LAUNDRY) {
2952 if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) {
2953 if (queue != PQ_NONE)
2955 vm_page_enqueue(PQ_LAUNDRY, m);
2957 KASSERT(queue == PQ_NONE,
2958 ("wired page %p is queued", m));
2963 * vm_page_unswappable
2965 * Put a page in the PQ_UNSWAPPABLE holding queue.
2968 vm_page_unswappable(vm_page_t m)
2971 vm_page_assert_locked(m);
2972 KASSERT(m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0,
2973 ("page %p already unswappable", m));
2974 if (m->queue != PQ_NONE)
2976 vm_page_enqueue(PQ_UNSWAPPABLE, m);
2980 * vm_page_try_to_free()
2982 * Attempt to free the page. If we cannot free it, we do nothing.
2983 * 1 is returned on success, 0 on failure.
2986 vm_page_try_to_free(vm_page_t m)
2989 vm_page_lock_assert(m, MA_OWNED);
2990 if (m->object != NULL)
2991 VM_OBJECT_ASSERT_WLOCKED(m->object);
2992 if (m->dirty || m->hold_count || m->wire_count ||
2993 (m->oflags & VPO_UNMANAGED) != 0 || vm_page_busied(m))
3005 * Apply the specified advice to the given page.
3007 * The object and page must be locked.
3010 vm_page_advise(vm_page_t m, int advice)
3013 vm_page_assert_locked(m);
3014 VM_OBJECT_ASSERT_WLOCKED(m->object);
3015 if (advice == MADV_FREE)
3017 * Mark the page clean. This will allow the page to be freed
3018 * without first paging it out. MADV_FREE pages are often
3019 * quickly reused by malloc(3), so we do not do anything that
3020 * would result in a page fault on a later access.
3023 else if (advice != MADV_DONTNEED) {
3024 if (advice == MADV_WILLNEED)
3025 vm_page_activate(m);
3030 * Clear any references to the page. Otherwise, the page daemon will
3031 * immediately reactivate the page.
3033 vm_page_aflag_clear(m, PGA_REFERENCED);
3035 if (advice != MADV_FREE && m->dirty == 0 && pmap_is_modified(m))
3039 * Place clean pages near the head of the inactive queue rather than
3040 * the tail, thus defeating the queue's LRU operation and ensuring that
3041 * the page will be reused quickly. Dirty pages not already in the
3042 * laundry are moved there.
3045 vm_page_deactivate_noreuse(m);
3051 * Grab a page, waiting until we are waken up due to the page
3052 * changing state. We keep on waiting, if the page continues
3053 * to be in the object. If the page doesn't exist, first allocate it
3054 * and then conditionally zero it.
3056 * This routine may sleep.
3058 * The object must be locked on entry. The lock will, however, be released
3059 * and reacquired if the routine sleeps.
3062 vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags)
3067 VM_OBJECT_ASSERT_WLOCKED(object);
3068 KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 ||
3069 (allocflags & VM_ALLOC_IGN_SBUSY) != 0,
3070 ("vm_page_grab: VM_ALLOC_SBUSY/VM_ALLOC_IGN_SBUSY mismatch"));
3072 if ((m = vm_page_lookup(object, pindex)) != NULL) {
3073 sleep = (allocflags & VM_ALLOC_IGN_SBUSY) != 0 ?
3074 vm_page_xbusied(m) : vm_page_busied(m);
3076 if ((allocflags & VM_ALLOC_NOWAIT) != 0)
3079 * Reference the page before unlocking and
3080 * sleeping so that the page daemon is less
3081 * likely to reclaim it.
3083 vm_page_aflag_set(m, PGA_REFERENCED);
3085 VM_OBJECT_WUNLOCK(object);
3086 vm_page_busy_sleep(m, "pgrbwt", (allocflags &
3087 VM_ALLOC_IGN_SBUSY) != 0);
3088 VM_OBJECT_WLOCK(object);
3091 if ((allocflags & VM_ALLOC_WIRED) != 0) {
3097 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) == 0)
3099 if ((allocflags & VM_ALLOC_SBUSY) != 0)
3104 m = vm_page_alloc(object, pindex, allocflags);
3106 if ((allocflags & VM_ALLOC_NOWAIT) != 0)
3108 VM_OBJECT_WUNLOCK(object);
3110 VM_OBJECT_WLOCK(object);
3113 if (allocflags & VM_ALLOC_ZERO && (m->flags & PG_ZERO) == 0)
3119 * Mapping function for valid or dirty bits in a page.
3121 * Inputs are required to range within a page.
3124 vm_page_bits(int base, int size)
3130 base + size <= PAGE_SIZE,
3131 ("vm_page_bits: illegal base/size %d/%d", base, size)
3134 if (size == 0) /* handle degenerate case */
3137 first_bit = base >> DEV_BSHIFT;
3138 last_bit = (base + size - 1) >> DEV_BSHIFT;
3140 return (((vm_page_bits_t)2 << last_bit) -
3141 ((vm_page_bits_t)1 << first_bit));
3145 * vm_page_set_valid_range:
3147 * Sets portions of a page valid. The arguments are expected
3148 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive
3149 * of any partial chunks touched by the range. The invalid portion of
3150 * such chunks will be zeroed.
3152 * (base + size) must be less then or equal to PAGE_SIZE.
3155 vm_page_set_valid_range(vm_page_t m, int base, int size)
3159 VM_OBJECT_ASSERT_WLOCKED(m->object);
3160 if (size == 0) /* handle degenerate case */
3164 * If the base is not DEV_BSIZE aligned and the valid
3165 * bit is clear, we have to zero out a portion of the
3168 if ((frag = rounddown2(base, DEV_BSIZE)) != base &&
3169 (m->valid & (1 << (base >> DEV_BSHIFT))) == 0)
3170 pmap_zero_page_area(m, frag, base - frag);
3173 * If the ending offset is not DEV_BSIZE aligned and the
3174 * valid bit is clear, we have to zero out a portion of
3177 endoff = base + size;
3178 if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff &&
3179 (m->valid & (1 << (endoff >> DEV_BSHIFT))) == 0)
3180 pmap_zero_page_area(m, endoff,
3181 DEV_BSIZE - (endoff & (DEV_BSIZE - 1)));
3184 * Assert that no previously invalid block that is now being validated
3187 KASSERT((~m->valid & vm_page_bits(base, size) & m->dirty) == 0,
3188 ("vm_page_set_valid_range: page %p is dirty", m));
3191 * Set valid bits inclusive of any overlap.
3193 m->valid |= vm_page_bits(base, size);
3197 * Clear the given bits from the specified page's dirty field.
3199 static __inline void
3200 vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits)
3203 #if PAGE_SIZE < 16384
3208 * If the object is locked and the page is neither exclusive busy nor
3209 * write mapped, then the page's dirty field cannot possibly be
3210 * set by a concurrent pmap operation.
3212 VM_OBJECT_ASSERT_WLOCKED(m->object);
3213 if (!vm_page_xbusied(m) && !pmap_page_is_write_mapped(m))
3214 m->dirty &= ~pagebits;
3217 * The pmap layer can call vm_page_dirty() without
3218 * holding a distinguished lock. The combination of
3219 * the object's lock and an atomic operation suffice
3220 * to guarantee consistency of the page dirty field.
3222 * For PAGE_SIZE == 32768 case, compiler already
3223 * properly aligns the dirty field, so no forcible
3224 * alignment is needed. Only require existence of
3225 * atomic_clear_64 when page size is 32768.
3227 addr = (uintptr_t)&m->dirty;
3228 #if PAGE_SIZE == 32768
3229 atomic_clear_64((uint64_t *)addr, pagebits);
3230 #elif PAGE_SIZE == 16384
3231 atomic_clear_32((uint32_t *)addr, pagebits);
3232 #else /* PAGE_SIZE <= 8192 */
3234 * Use a trick to perform a 32-bit atomic on the
3235 * containing aligned word, to not depend on the existence
3236 * of atomic_clear_{8, 16}.
3238 shift = addr & (sizeof(uint32_t) - 1);
3239 #if BYTE_ORDER == BIG_ENDIAN
3240 shift = (sizeof(uint32_t) - sizeof(m->dirty) - shift) * NBBY;
3244 addr &= ~(sizeof(uint32_t) - 1);
3245 atomic_clear_32((uint32_t *)addr, pagebits << shift);
3246 #endif /* PAGE_SIZE */
3251 * vm_page_set_validclean:
3253 * Sets portions of a page valid and clean. The arguments are expected
3254 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive
3255 * of any partial chunks touched by the range. The invalid portion of
3256 * such chunks will be zero'd.
3258 * (base + size) must be less then or equal to PAGE_SIZE.
3261 vm_page_set_validclean(vm_page_t m, int base, int size)
3263 vm_page_bits_t oldvalid, pagebits;
3266 VM_OBJECT_ASSERT_WLOCKED(m->object);
3267 if (size == 0) /* handle degenerate case */
3271 * If the base is not DEV_BSIZE aligned and the valid
3272 * bit is clear, we have to zero out a portion of the
3275 if ((frag = rounddown2(base, DEV_BSIZE)) != base &&
3276 (m->valid & ((vm_page_bits_t)1 << (base >> DEV_BSHIFT))) == 0)
3277 pmap_zero_page_area(m, frag, base - frag);
3280 * If the ending offset is not DEV_BSIZE aligned and the
3281 * valid bit is clear, we have to zero out a portion of
3284 endoff = base + size;
3285 if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff &&
3286 (m->valid & ((vm_page_bits_t)1 << (endoff >> DEV_BSHIFT))) == 0)
3287 pmap_zero_page_area(m, endoff,
3288 DEV_BSIZE - (endoff & (DEV_BSIZE - 1)));
3291 * Set valid, clear dirty bits. If validating the entire
3292 * page we can safely clear the pmap modify bit. We also
3293 * use this opportunity to clear the VPO_NOSYNC flag. If a process
3294 * takes a write fault on a MAP_NOSYNC memory area the flag will
3297 * We set valid bits inclusive of any overlap, but we can only
3298 * clear dirty bits for DEV_BSIZE chunks that are fully within
3301 oldvalid = m->valid;
3302 pagebits = vm_page_bits(base, size);
3303 m->valid |= pagebits;
3305 if ((frag = base & (DEV_BSIZE - 1)) != 0) {
3306 frag = DEV_BSIZE - frag;
3312 pagebits = vm_page_bits(base, size & (DEV_BSIZE - 1));
3314 if (base == 0 && size == PAGE_SIZE) {
3316 * The page can only be modified within the pmap if it is
3317 * mapped, and it can only be mapped if it was previously
3320 if (oldvalid == VM_PAGE_BITS_ALL)
3322 * Perform the pmap_clear_modify() first. Otherwise,
3323 * a concurrent pmap operation, such as
3324 * pmap_protect(), could clear a modification in the
3325 * pmap and set the dirty field on the page before
3326 * pmap_clear_modify() had begun and after the dirty
3327 * field was cleared here.
3329 pmap_clear_modify(m);
3331 m->oflags &= ~VPO_NOSYNC;
3332 } else if (oldvalid != VM_PAGE_BITS_ALL)
3333 m->dirty &= ~pagebits;
3335 vm_page_clear_dirty_mask(m, pagebits);
3339 vm_page_clear_dirty(vm_page_t m, int base, int size)
3342 vm_page_clear_dirty_mask(m, vm_page_bits(base, size));
3346 * vm_page_set_invalid:
3348 * Invalidates DEV_BSIZE'd chunks within a page. Both the
3349 * valid and dirty bits for the effected areas are cleared.
3352 vm_page_set_invalid(vm_page_t m, int base, int size)
3354 vm_page_bits_t bits;
3358 VM_OBJECT_ASSERT_WLOCKED(object);
3359 if (object->type == OBJT_VNODE && base == 0 && IDX_TO_OFF(m->pindex) +
3360 size >= object->un_pager.vnp.vnp_size)
3361 bits = VM_PAGE_BITS_ALL;
3363 bits = vm_page_bits(base, size);
3364 if (object->ref_count != 0 && m->valid == VM_PAGE_BITS_ALL &&
3367 KASSERT((bits == 0 && m->valid == VM_PAGE_BITS_ALL) ||
3368 !pmap_page_is_mapped(m),
3369 ("vm_page_set_invalid: page %p is mapped", m));
3375 * vm_page_zero_invalid()
3377 * The kernel assumes that the invalid portions of a page contain
3378 * garbage, but such pages can be mapped into memory by user code.
3379 * When this occurs, we must zero out the non-valid portions of the
3380 * page so user code sees what it expects.
3382 * Pages are most often semi-valid when the end of a file is mapped
3383 * into memory and the file's size is not page aligned.
3386 vm_page_zero_invalid(vm_page_t m, boolean_t setvalid)
3391 VM_OBJECT_ASSERT_WLOCKED(m->object);
3393 * Scan the valid bits looking for invalid sections that
3394 * must be zeroed. Invalid sub-DEV_BSIZE'd areas ( where the
3395 * valid bit may be set ) have already been zeroed by
3396 * vm_page_set_validclean().
3398 for (b = i = 0; i <= PAGE_SIZE / DEV_BSIZE; ++i) {
3399 if (i == (PAGE_SIZE / DEV_BSIZE) ||
3400 (m->valid & ((vm_page_bits_t)1 << i))) {
3402 pmap_zero_page_area(m,
3403 b << DEV_BSHIFT, (i - b) << DEV_BSHIFT);
3410 * setvalid is TRUE when we can safely set the zero'd areas
3411 * as being valid. We can do this if there are no cache consistancy
3412 * issues. e.g. it is ok to do with UFS, but not ok to do with NFS.
3415 m->valid = VM_PAGE_BITS_ALL;
3421 * Is (partial) page valid? Note that the case where size == 0
3422 * will return FALSE in the degenerate case where the page is
3423 * entirely invalid, and TRUE otherwise.
3426 vm_page_is_valid(vm_page_t m, int base, int size)
3428 vm_page_bits_t bits;
3430 VM_OBJECT_ASSERT_LOCKED(m->object);
3431 bits = vm_page_bits(base, size);
3432 return (m->valid != 0 && (m->valid & bits) == bits);
3436 * vm_page_ps_is_valid:
3438 * Returns TRUE if the entire (super)page is valid and FALSE otherwise.
3441 vm_page_ps_is_valid(vm_page_t m)
3445 VM_OBJECT_ASSERT_LOCKED(m->object);
3446 npages = atop(pagesizes[m->psind]);
3449 * The physically contiguous pages that make up a superpage, i.e., a
3450 * page with a page size index ("psind") greater than zero, will
3451 * occupy adjacent entries in vm_page_array[].
3453 for (i = 0; i < npages; i++) {
3454 if (m[i].valid != VM_PAGE_BITS_ALL)
3461 * Set the page's dirty bits if the page is modified.
3464 vm_page_test_dirty(vm_page_t m)
3467 VM_OBJECT_ASSERT_WLOCKED(m->object);
3468 if (m->dirty != VM_PAGE_BITS_ALL && pmap_is_modified(m))
3473 vm_page_lock_KBI(vm_page_t m, const char *file, int line)
3476 mtx_lock_flags_(vm_page_lockptr(m), 0, file, line);
3480 vm_page_unlock_KBI(vm_page_t m, const char *file, int line)
3483 mtx_unlock_flags_(vm_page_lockptr(m), 0, file, line);
3487 vm_page_trylock_KBI(vm_page_t m, const char *file, int line)
3490 return (mtx_trylock_flags_(vm_page_lockptr(m), 0, file, line));
3493 #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
3495 vm_page_assert_locked_KBI(vm_page_t m, const char *file, int line)
3498 vm_page_lock_assert_KBI(m, MA_OWNED, file, line);
3502 vm_page_lock_assert_KBI(vm_page_t m, int a, const char *file, int line)
3505 mtx_assert_(vm_page_lockptr(m), a, file, line);
3511 vm_page_object_lock_assert(vm_page_t m)
3515 * Certain of the page's fields may only be modified by the
3516 * holder of the containing object's lock or the exclusive busy.
3517 * holder. Unfortunately, the holder of the write busy is
3518 * not recorded, and thus cannot be checked here.
3520 if (m->object != NULL && !vm_page_xbusied(m))
3521 VM_OBJECT_ASSERT_WLOCKED(m->object);
3525 vm_page_assert_pga_writeable(vm_page_t m, uint8_t bits)
3528 if ((bits & PGA_WRITEABLE) == 0)
3532 * The PGA_WRITEABLE flag can only be set if the page is
3533 * managed, is exclusively busied or the object is locked.
3534 * Currently, this flag is only set by pmap_enter().
3536 KASSERT((m->oflags & VPO_UNMANAGED) == 0,
3537 ("PGA_WRITEABLE on unmanaged page"));
3538 if (!vm_page_xbusied(m))
3539 VM_OBJECT_ASSERT_LOCKED(m->object);
3543 #include "opt_ddb.h"
3545 #include <sys/kernel.h>
3547 #include <ddb/ddb.h>
3549 DB_SHOW_COMMAND(page, vm_page_print_page_info)
3552 db_printf("vm_cnt.v_free_count: %d\n", vm_cnt.v_free_count);
3553 db_printf("vm_cnt.v_inactive_count: %d\n", vm_cnt.v_inactive_count);
3554 db_printf("vm_cnt.v_active_count: %d\n", vm_cnt.v_active_count);
3555 db_printf("vm_cnt.v_laundry_count: %d\n", vm_cnt.v_laundry_count);
3556 db_printf("vm_cnt.v_wire_count: %d\n", vm_cnt.v_wire_count);
3557 db_printf("vm_cnt.v_free_reserved: %d\n", vm_cnt.v_free_reserved);
3558 db_printf("vm_cnt.v_free_min: %d\n", vm_cnt.v_free_min);
3559 db_printf("vm_cnt.v_free_target: %d\n", vm_cnt.v_free_target);
3560 db_printf("vm_cnt.v_inactive_target: %d\n", vm_cnt.v_inactive_target);
3563 DB_SHOW_COMMAND(pageq, vm_page_print_pageq_info)
3567 db_printf("pq_free %d\n", vm_cnt.v_free_count);
3568 for (dom = 0; dom < vm_ndomains; dom++) {
3570 "dom %d page_cnt %d free %d pq_act %d pq_inact %d pq_laund %d pq_unsw %d\n",
3572 vm_dom[dom].vmd_page_count,
3573 vm_dom[dom].vmd_free_count,
3574 vm_dom[dom].vmd_pagequeues[PQ_ACTIVE].pq_cnt,
3575 vm_dom[dom].vmd_pagequeues[PQ_INACTIVE].pq_cnt,
3576 vm_dom[dom].vmd_pagequeues[PQ_LAUNDRY].pq_cnt,
3577 vm_dom[dom].vmd_pagequeues[PQ_UNSWAPPABLE].pq_cnt);
3581 DB_SHOW_COMMAND(pginfo, vm_page_print_pginfo)
3587 db_printf("show pginfo addr\n");
3591 phys = strchr(modif, 'p') != NULL;
3593 m = PHYS_TO_VM_PAGE(addr);
3595 m = (vm_page_t)addr;
3597 "page %p obj %p pidx 0x%jx phys 0x%jx q %d hold %d wire %d\n"
3598 " af 0x%x of 0x%x f 0x%x act %d busy %x valid 0x%x dirty 0x%x\n",
3599 m, m->object, (uintmax_t)m->pindex, (uintmax_t)m->phys_addr,
3600 m->queue, m->hold_count, m->wire_count, m->aflags, m->oflags,
3601 m->flags, m->act_count, m->busy_lock, m->valid, m->dirty);