2 * SPDX-License-Identifier: (BSD-3-Clause AND MIT-CMU)
4 * Copyright (c) 1991 Regents of the University of California.
6 * Copyright (c) 1998 Matthew Dillon. All Rights Reserved.
8 * This code is derived from software contributed to Berkeley by
9 * The Mach Operating System project at Carnegie-Mellon University.
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * from: @(#)vm_page.c 7.4 (Berkeley) 5/7/91
39 * Copyright (c) 1987, 1990 Carnegie-Mellon University.
40 * All rights reserved.
42 * Authors: Avadis Tevanian, Jr., Michael Wayne Young
44 * Permission to use, copy, modify and distribute this software and
45 * its documentation is hereby granted, provided that both the copyright
46 * notice and this permission notice appear in all copies of the
47 * software, derivative works or modified versions, and any portions
48 * thereof, and that both notices appear in supporting documentation.
50 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
51 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
52 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
54 * Carnegie Mellon requests users of this software to return to
56 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
57 * School of Computer Science
58 * Carnegie Mellon University
59 * Pittsburgh PA 15213-3890
61 * any improvements or extensions that they make and grant Carnegie the
62 * rights to redistribute these changes.
66 * Resident memory management module.
69 #include <sys/cdefs.h>
70 __FBSDID("$FreeBSD$");
74 #include <sys/param.h>
75 #include <sys/systm.h>
76 #include <sys/counter.h>
77 #include <sys/domainset.h>
78 #include <sys/kernel.h>
79 #include <sys/limits.h>
80 #include <sys/linker.h>
82 #include <sys/malloc.h>
84 #include <sys/msgbuf.h>
85 #include <sys/mutex.h>
87 #include <sys/rwlock.h>
88 #include <sys/sleepqueue.h>
90 #include <sys/sched.h>
92 #include <sys/sysctl.h>
93 #include <sys/vmmeter.h>
94 #include <sys/vnode.h>
98 #include <vm/vm_param.h>
99 #include <vm/vm_domainset.h>
100 #include <vm/vm_kern.h>
101 #include <vm/vm_map.h>
102 #include <vm/vm_object.h>
103 #include <vm/vm_page.h>
104 #include <vm/vm_pageout.h>
105 #include <vm/vm_phys.h>
106 #include <vm/vm_pagequeue.h>
107 #include <vm/vm_pager.h>
108 #include <vm/vm_radix.h>
109 #include <vm/vm_reserv.h>
110 #include <vm/vm_extern.h>
112 #include <vm/uma_int.h>
114 #include <machine/md_var.h>
116 extern int uma_startup_count(int);
117 extern void uma_startup(void *, int);
118 extern int vmem_startup_count(void);
120 struct vm_domain vm_dom[MAXMEMDOM];
122 DPCPU_DEFINE_STATIC(struct vm_batchqueue, pqbatch[MAXMEMDOM][PQ_COUNT]);
124 struct mtx_padalign __exclusive_cache_line pa_lock[PA_LOCK_COUNT];
126 struct mtx_padalign __exclusive_cache_line vm_domainset_lock;
127 /* The following fields are protected by the domainset lock. */
128 domainset_t __exclusive_cache_line vm_min_domains;
129 domainset_t __exclusive_cache_line vm_severe_domains;
130 static int vm_min_waiters;
131 static int vm_severe_waiters;
132 static int vm_pageproc_waiters;
134 static SYSCTL_NODE(_vm_stats, OID_AUTO, page, CTLFLAG_RD, 0,
135 "VM page statistics");
137 static counter_u64_t queue_ops = EARLY_COUNTER;
138 SYSCTL_COUNTER_U64(_vm_stats_page, OID_AUTO, queue_ops,
139 CTLFLAG_RD, &queue_ops,
140 "Number of batched queue operations");
142 static counter_u64_t queue_nops = EARLY_COUNTER;
143 SYSCTL_COUNTER_U64(_vm_stats_page, OID_AUTO, queue_nops,
144 CTLFLAG_RD, &queue_nops,
145 "Number of batched queue operations with no effects");
148 counter_startup(void)
151 queue_ops = counter_u64_alloc(M_WAITOK);
152 queue_nops = counter_u64_alloc(M_WAITOK);
154 SYSINIT(page_counters, SI_SUB_CPU, SI_ORDER_ANY, counter_startup, NULL);
157 * bogus page -- for I/O to/from partially complete buffers,
158 * or for paging into sparsely invalid regions.
160 vm_page_t bogus_page;
162 vm_page_t vm_page_array;
163 long vm_page_array_size;
166 static int boot_pages;
167 SYSCTL_INT(_vm, OID_AUTO, boot_pages, CTLFLAG_RDTUN | CTLFLAG_NOFETCH,
169 "number of pages allocated for bootstrapping the VM system");
171 static TAILQ_HEAD(, vm_page) blacklist_head;
172 static int sysctl_vm_page_blacklist(SYSCTL_HANDLER_ARGS);
173 SYSCTL_PROC(_vm, OID_AUTO, page_blacklist, CTLTYPE_STRING | CTLFLAG_RD |
174 CTLFLAG_MPSAFE, NULL, 0, sysctl_vm_page_blacklist, "A", "Blacklist pages");
176 static uma_zone_t fakepg_zone;
178 static void vm_page_alloc_check(vm_page_t m);
179 static void _vm_page_busy_sleep(vm_object_t obj, vm_page_t m,
180 const char *wmesg, bool nonshared, bool locked);
181 static void vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits);
182 static void vm_page_dequeue_complete(vm_page_t m);
183 static void vm_page_enqueue(vm_page_t m, uint8_t queue);
184 static bool vm_page_free_prep(vm_page_t m);
185 static void vm_page_free_toq(vm_page_t m);
186 static void vm_page_init(void *dummy);
187 static int vm_page_insert_after(vm_page_t m, vm_object_t object,
188 vm_pindex_t pindex, vm_page_t mpred);
189 static void vm_page_insert_radixdone(vm_page_t m, vm_object_t object,
191 static void vm_page_mvqueue(vm_page_t m, uint8_t queue);
192 static int vm_page_reclaim_run(int req_class, int domain, u_long npages,
193 vm_page_t m_run, vm_paddr_t high);
194 static int vm_domain_alloc_fail(struct vm_domain *vmd, vm_object_t object,
196 static int vm_page_zone_import(void *arg, void **store, int cnt, int domain,
198 static void vm_page_zone_release(void *arg, void **store, int cnt);
200 SYSINIT(vm_page, SI_SUB_VM, SI_ORDER_SECOND, vm_page_init, NULL);
203 vm_page_init(void *dummy)
206 fakepg_zone = uma_zcreate("fakepg", sizeof(struct vm_page), NULL, NULL,
207 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE | UMA_ZONE_VM);
208 bogus_page = vm_page_alloc(NULL, 0, VM_ALLOC_NOOBJ |
209 VM_ALLOC_NORMAL | VM_ALLOC_WIRED);
213 * The cache page zone is initialized later since we need to be able to allocate
214 * pages before UMA is fully initialized.
217 vm_page_init_cache_zones(void *dummy __unused)
219 struct vm_domain *vmd;
220 struct vm_pgcache *pgcache;
221 int cache, domain, maxcache, pool;
224 TUNABLE_INT_FETCH("vm.pgcache_zone_max", &maxcache);
225 for (domain = 0; domain < vm_ndomains; domain++) {
226 vmd = VM_DOMAIN(domain);
227 for (pool = 0; pool < VM_NFREEPOOL; pool++) {
228 pgcache = &vmd->vmd_pgcache[pool];
229 pgcache->domain = domain;
230 pgcache->pool = pool;
231 pgcache->zone = uma_zcache_create("vm pgcache",
232 PAGE_SIZE, NULL, NULL, NULL, NULL,
233 vm_page_zone_import, vm_page_zone_release, pgcache,
237 * Limit each pool's zone to 0.1% of the pages in the
240 cache = maxcache != 0 ? maxcache :
241 vmd->vmd_page_count / 1000;
242 uma_zone_set_maxcache(pgcache->zone, cache);
246 SYSINIT(vm_page2, SI_SUB_VM_CONF, SI_ORDER_ANY, vm_page_init_cache_zones, NULL);
248 /* Make sure that u_long is at least 64 bits when PAGE_SIZE is 32K. */
249 #if PAGE_SIZE == 32768
251 CTASSERT(sizeof(u_long) >= 8);
258 * Sets the page size, perhaps based upon the memory
259 * size. Must be called before any use of page-size
260 * dependent functions.
263 vm_set_page_size(void)
265 if (vm_cnt.v_page_size == 0)
266 vm_cnt.v_page_size = PAGE_SIZE;
267 if (((vm_cnt.v_page_size - 1) & vm_cnt.v_page_size) != 0)
268 panic("vm_set_page_size: page size not a power of two");
272 * vm_page_blacklist_next:
274 * Find the next entry in the provided string of blacklist
275 * addresses. Entries are separated by space, comma, or newline.
276 * If an invalid integer is encountered then the rest of the
277 * string is skipped. Updates the list pointer to the next
278 * character, or NULL if the string is exhausted or invalid.
281 vm_page_blacklist_next(char **list, char *end)
286 if (list == NULL || *list == NULL)
294 * If there's no end pointer then the buffer is coming from
295 * the kenv and we know it's null-terminated.
298 end = *list + strlen(*list);
300 /* Ensure that strtoq() won't walk off the end */
302 if (*end == '\n' || *end == ' ' || *end == ',')
305 printf("Blacklist not terminated, skipping\n");
311 for (pos = *list; *pos != '\0'; pos = cp) {
312 bad = strtoq(pos, &cp, 0);
313 if (*cp == '\0' || *cp == ' ' || *cp == ',' || *cp == '\n') {
322 if (*cp == '\0' || ++cp >= end)
326 return (trunc_page(bad));
328 printf("Garbage in RAM blacklist, skipping\n");
334 vm_page_blacklist_add(vm_paddr_t pa, bool verbose)
336 struct vm_domain *vmd;
340 m = vm_phys_paddr_to_vm_page(pa);
342 return (true); /* page does not exist, no failure */
344 vmd = vm_pagequeue_domain(m);
345 vm_domain_free_lock(vmd);
346 ret = vm_phys_unfree_page(m);
347 vm_domain_free_unlock(vmd);
349 vm_domain_freecnt_inc(vmd, -1);
350 TAILQ_INSERT_TAIL(&blacklist_head, m, listq);
352 printf("Skipping page with pa 0x%jx\n", (uintmax_t)pa);
358 * vm_page_blacklist_check:
360 * Iterate through the provided string of blacklist addresses, pulling
361 * each entry out of the physical allocator free list and putting it
362 * onto a list for reporting via the vm.page_blacklist sysctl.
365 vm_page_blacklist_check(char *list, char *end)
371 while (next != NULL) {
372 if ((pa = vm_page_blacklist_next(&next, end)) == 0)
374 vm_page_blacklist_add(pa, bootverbose);
379 * vm_page_blacklist_load:
381 * Search for a special module named "ram_blacklist". It'll be a
382 * plain text file provided by the user via the loader directive
386 vm_page_blacklist_load(char **list, char **end)
395 mod = preload_search_by_type("ram_blacklist");
397 ptr = preload_fetch_addr(mod);
398 len = preload_fetch_size(mod);
409 sysctl_vm_page_blacklist(SYSCTL_HANDLER_ARGS)
416 error = sysctl_wire_old_buffer(req, 0);
419 sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
420 TAILQ_FOREACH(m, &blacklist_head, listq) {
421 sbuf_printf(&sbuf, "%s%#jx", first ? "" : ",",
422 (uintmax_t)m->phys_addr);
425 error = sbuf_finish(&sbuf);
431 * Initialize a dummy page for use in scans of the specified paging queue.
432 * In principle, this function only needs to set the flag PG_MARKER.
433 * Nonetheless, it write busies the page as a safety precaution.
436 vm_page_init_marker(vm_page_t marker, int queue, uint16_t aflags)
439 bzero(marker, sizeof(*marker));
440 marker->flags = PG_MARKER;
441 marker->a.flags = aflags;
442 marker->busy_lock = VPB_CURTHREAD_EXCLUSIVE;
443 marker->a.queue = queue;
447 vm_page_domain_init(int domain)
449 struct vm_domain *vmd;
450 struct vm_pagequeue *pq;
453 vmd = VM_DOMAIN(domain);
454 bzero(vmd, sizeof(*vmd));
455 *__DECONST(char **, &vmd->vmd_pagequeues[PQ_INACTIVE].pq_name) =
456 "vm inactive pagequeue";
457 *__DECONST(char **, &vmd->vmd_pagequeues[PQ_ACTIVE].pq_name) =
458 "vm active pagequeue";
459 *__DECONST(char **, &vmd->vmd_pagequeues[PQ_LAUNDRY].pq_name) =
460 "vm laundry pagequeue";
461 *__DECONST(char **, &vmd->vmd_pagequeues[PQ_UNSWAPPABLE].pq_name) =
462 "vm unswappable pagequeue";
463 vmd->vmd_domain = domain;
464 vmd->vmd_page_count = 0;
465 vmd->vmd_free_count = 0;
467 vmd->vmd_oom = FALSE;
468 for (i = 0; i < PQ_COUNT; i++) {
469 pq = &vmd->vmd_pagequeues[i];
470 TAILQ_INIT(&pq->pq_pl);
471 mtx_init(&pq->pq_mutex, pq->pq_name, "vm pagequeue",
472 MTX_DEF | MTX_DUPOK);
474 vm_page_init_marker(&vmd->vmd_markers[i], i, 0);
476 mtx_init(&vmd->vmd_free_mtx, "vm page free queue", NULL, MTX_DEF);
477 mtx_init(&vmd->vmd_pageout_mtx, "vm pageout lock", NULL, MTX_DEF);
478 snprintf(vmd->vmd_name, sizeof(vmd->vmd_name), "%d", domain);
481 * inacthead is used to provide FIFO ordering for LRU-bypassing
484 vm_page_init_marker(&vmd->vmd_inacthead, PQ_INACTIVE, PGA_ENQUEUED);
485 TAILQ_INSERT_HEAD(&vmd->vmd_pagequeues[PQ_INACTIVE].pq_pl,
486 &vmd->vmd_inacthead, plinks.q);
489 * The clock pages are used to implement active queue scanning without
490 * requeues. Scans start at clock[0], which is advanced after the scan
491 * ends. When the two clock hands meet, they are reset and scanning
492 * resumes from the head of the queue.
494 vm_page_init_marker(&vmd->vmd_clock[0], PQ_ACTIVE, PGA_ENQUEUED);
495 vm_page_init_marker(&vmd->vmd_clock[1], PQ_ACTIVE, PGA_ENQUEUED);
496 TAILQ_INSERT_HEAD(&vmd->vmd_pagequeues[PQ_ACTIVE].pq_pl,
497 &vmd->vmd_clock[0], plinks.q);
498 TAILQ_INSERT_TAIL(&vmd->vmd_pagequeues[PQ_ACTIVE].pq_pl,
499 &vmd->vmd_clock[1], plinks.q);
503 * Initialize a physical page in preparation for adding it to the free
507 vm_page_init_page(vm_page_t m, vm_paddr_t pa, int segind)
512 m->busy_lock = VPB_UNBUSIED;
513 m->flags = m->a.flags = 0;
515 m->a.queue = PQ_NONE;
518 m->order = VM_NFREEORDER;
519 m->pool = VM_FREEPOOL_DEFAULT;
520 m->valid = m->dirty = 0;
524 #ifndef PMAP_HAS_PAGE_ARRAY
526 vm_page_array_alloc(vm_offset_t *vaddr, vm_paddr_t end, vm_paddr_t page_range)
531 * Reserve an unmapped guard page to trap access to vm_page_array[-1].
532 * However, because this page is allocated from KVM, out-of-bounds
533 * accesses using the direct map will not be trapped.
538 * Allocate physical memory for the page structures, and map it.
540 new_end = trunc_page(end - page_range * sizeof(struct vm_page));
541 vm_page_array = (vm_page_t)pmap_map(vaddr, new_end, end,
542 VM_PROT_READ | VM_PROT_WRITE);
543 vm_page_array_size = page_range;
552 * Initializes the resident memory module. Allocates physical memory for
553 * bootstrapping UMA and some data structures that are used to manage
554 * physical pages. Initializes these structures, and populates the free
558 vm_page_startup(vm_offset_t vaddr)
560 struct vm_phys_seg *seg;
562 char *list, *listend;
564 vm_paddr_t end, high_avail, low_avail, new_end, size;
565 vm_paddr_t page_range __unused;
566 vm_paddr_t last_pa, pa;
568 int biggestone, i, segind;
572 #if defined(__i386__) && defined(VM_PHYSSEG_DENSE)
576 vaddr = round_page(vaddr);
578 vm_phys_early_startup();
579 biggestone = vm_phys_avail_largest();
580 end = phys_avail[biggestone+1];
583 * Initialize the page and queue locks.
585 mtx_init(&vm_domainset_lock, "vm domainset lock", NULL, MTX_DEF);
586 for (i = 0; i < PA_LOCK_COUNT; i++)
587 mtx_init(&pa_lock[i], "vm page", NULL, MTX_DEF);
588 for (i = 0; i < vm_ndomains; i++)
589 vm_page_domain_init(i);
592 * Allocate memory for use when boot strapping the kernel memory
593 * allocator. Tell UMA how many zones we are going to create
594 * before going fully functional. UMA will add its zones.
596 * VM startup zones: vmem, vmem_btag, VM OBJECT, RADIX NODE, MAP,
597 * KMAP ENTRY, MAP ENTRY, VMSPACE.
599 boot_pages = uma_startup_count(8);
601 #ifndef UMA_MD_SMALL_ALLOC
602 /* vmem_startup() calls uma_prealloc(). */
603 boot_pages += vmem_startup_count();
604 /* vm_map_startup() calls uma_prealloc(). */
605 boot_pages += howmany(MAX_KMAP,
606 slab_ipers(sizeof(struct vm_map), UMA_ALIGN_PTR));
609 * Before going fully functional kmem_init() does allocation
610 * from "KMAP ENTRY" and vmem_create() does allocation from "vmem".
615 * CTFLAG_RDTUN doesn't work during the early boot process, so we must
616 * manually fetch the value.
618 TUNABLE_INT_FETCH("vm.boot_pages", &boot_pages);
619 new_end = end - (boot_pages * UMA_SLAB_SIZE);
620 new_end = trunc_page(new_end);
621 mapped = pmap_map(&vaddr, new_end, end,
622 VM_PROT_READ | VM_PROT_WRITE);
623 bzero((void *)mapped, end - new_end);
624 uma_startup((void *)mapped, boot_pages);
627 witness_size = round_page(witness_startup_count());
628 new_end -= witness_size;
629 mapped = pmap_map(&vaddr, new_end, new_end + witness_size,
630 VM_PROT_READ | VM_PROT_WRITE);
631 bzero((void *)mapped, witness_size);
632 witness_startup((void *)mapped);
635 #if defined(__aarch64__) || defined(__amd64__) || defined(__arm__) || \
636 defined(__i386__) || defined(__mips__) || defined(__riscv) || \
637 defined(__powerpc64__)
639 * Allocate a bitmap to indicate that a random physical page
640 * needs to be included in a minidump.
642 * The amd64 port needs this to indicate which direct map pages
643 * need to be dumped, via calls to dump_add_page()/dump_drop_page().
645 * However, i386 still needs this workspace internally within the
646 * minidump code. In theory, they are not needed on i386, but are
647 * included should the sf_buf code decide to use them.
650 for (i = 0; dump_avail[i + 1] != 0; i += 2)
651 if (dump_avail[i + 1] > last_pa)
652 last_pa = dump_avail[i + 1];
653 page_range = last_pa / PAGE_SIZE;
654 vm_page_dump_size = round_page(roundup2(page_range, NBBY) / NBBY);
655 new_end -= vm_page_dump_size;
656 vm_page_dump = (void *)(uintptr_t)pmap_map(&vaddr, new_end,
657 new_end + vm_page_dump_size, VM_PROT_READ | VM_PROT_WRITE);
658 bzero((void *)vm_page_dump, vm_page_dump_size);
662 #if defined(__aarch64__) || defined(__amd64__) || defined(__mips__) || \
663 defined(__riscv) || defined(__powerpc64__)
665 * Include the UMA bootstrap pages, witness pages and vm_page_dump
666 * in a crash dump. When pmap_map() uses the direct map, they are
667 * not automatically included.
669 for (pa = new_end; pa < end; pa += PAGE_SIZE)
672 phys_avail[biggestone + 1] = new_end;
675 * Request that the physical pages underlying the message buffer be
676 * included in a crash dump. Since the message buffer is accessed
677 * through the direct map, they are not automatically included.
679 pa = DMAP_TO_PHYS((vm_offset_t)msgbufp->msg_ptr);
680 last_pa = pa + round_page(msgbufsize);
681 while (pa < last_pa) {
687 * Compute the number of pages of memory that will be available for
688 * use, taking into account the overhead of a page structure per page.
689 * In other words, solve
690 * "available physical memory" - round_page(page_range *
691 * sizeof(struct vm_page)) = page_range * PAGE_SIZE
694 low_avail = phys_avail[0];
695 high_avail = phys_avail[1];
696 for (i = 0; i < vm_phys_nsegs; i++) {
697 if (vm_phys_segs[i].start < low_avail)
698 low_avail = vm_phys_segs[i].start;
699 if (vm_phys_segs[i].end > high_avail)
700 high_avail = vm_phys_segs[i].end;
702 /* Skip the first chunk. It is already accounted for. */
703 for (i = 2; phys_avail[i + 1] != 0; i += 2) {
704 if (phys_avail[i] < low_avail)
705 low_avail = phys_avail[i];
706 if (phys_avail[i + 1] > high_avail)
707 high_avail = phys_avail[i + 1];
709 first_page = low_avail / PAGE_SIZE;
710 #ifdef VM_PHYSSEG_SPARSE
712 for (i = 0; i < vm_phys_nsegs; i++)
713 size += vm_phys_segs[i].end - vm_phys_segs[i].start;
714 for (i = 0; phys_avail[i + 1] != 0; i += 2)
715 size += phys_avail[i + 1] - phys_avail[i];
716 #elif defined(VM_PHYSSEG_DENSE)
717 size = high_avail - low_avail;
719 #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined."
722 #ifdef PMAP_HAS_PAGE_ARRAY
723 pmap_page_array_startup(size / PAGE_SIZE);
724 biggestone = vm_phys_avail_largest();
725 end = new_end = phys_avail[biggestone + 1];
727 #ifdef VM_PHYSSEG_DENSE
729 * In the VM_PHYSSEG_DENSE case, the number of pages can account for
730 * the overhead of a page structure per page only if vm_page_array is
731 * allocated from the last physical memory chunk. Otherwise, we must
732 * allocate page structures representing the physical memory
733 * underlying vm_page_array, even though they will not be used.
735 if (new_end != high_avail)
736 page_range = size / PAGE_SIZE;
740 page_range = size / (PAGE_SIZE + sizeof(struct vm_page));
743 * If the partial bytes remaining are large enough for
744 * a page (PAGE_SIZE) without a corresponding
745 * 'struct vm_page', then new_end will contain an
746 * extra page after subtracting the length of the VM
747 * page array. Compensate by subtracting an extra
750 if (size % (PAGE_SIZE + sizeof(struct vm_page)) >= PAGE_SIZE) {
751 if (new_end == high_avail)
752 high_avail -= PAGE_SIZE;
753 new_end -= PAGE_SIZE;
757 new_end = vm_page_array_alloc(&vaddr, end, page_range);
760 #if VM_NRESERVLEVEL > 0
762 * Allocate physical memory for the reservation management system's
763 * data structures, and map it.
765 new_end = vm_reserv_startup(&vaddr, new_end);
767 #if defined(__aarch64__) || defined(__amd64__) || defined(__mips__) || \
768 defined(__riscv) || defined(__powerpc64__)
770 * Include vm_page_array and vm_reserv_array in a crash dump.
772 for (pa = new_end; pa < end; pa += PAGE_SIZE)
775 phys_avail[biggestone + 1] = new_end;
778 * Add physical memory segments corresponding to the available
781 for (i = 0; phys_avail[i + 1] != 0; i += 2)
782 if (vm_phys_avail_size(i) != 0)
783 vm_phys_add_seg(phys_avail[i], phys_avail[i + 1]);
786 * Initialize the physical memory allocator.
791 * Initialize the page structures and add every available page to the
792 * physical memory allocator's free lists.
794 #if defined(__i386__) && defined(VM_PHYSSEG_DENSE)
795 for (ii = 0; ii < vm_page_array_size; ii++) {
796 m = &vm_page_array[ii];
797 vm_page_init_page(m, (first_page + ii) << PAGE_SHIFT, 0);
798 m->flags = PG_FICTITIOUS;
801 vm_cnt.v_page_count = 0;
802 for (segind = 0; segind < vm_phys_nsegs; segind++) {
803 seg = &vm_phys_segs[segind];
804 for (m = seg->first_page, pa = seg->start; pa < seg->end;
805 m++, pa += PAGE_SIZE)
806 vm_page_init_page(m, pa, segind);
809 * Add the segment to the free lists only if it is covered by
810 * one of the ranges in phys_avail. Because we've added the
811 * ranges to the vm_phys_segs array, we can assume that each
812 * segment is either entirely contained in one of the ranges,
813 * or doesn't overlap any of them.
815 for (i = 0; phys_avail[i + 1] != 0; i += 2) {
816 struct vm_domain *vmd;
818 if (seg->start < phys_avail[i] ||
819 seg->end > phys_avail[i + 1])
823 pagecount = (u_long)atop(seg->end - seg->start);
825 vmd = VM_DOMAIN(seg->domain);
826 vm_domain_free_lock(vmd);
827 vm_phys_enqueue_contig(m, pagecount);
828 vm_domain_free_unlock(vmd);
829 vm_domain_freecnt_inc(vmd, pagecount);
830 vm_cnt.v_page_count += (u_int)pagecount;
832 vmd = VM_DOMAIN(seg->domain);
833 vmd->vmd_page_count += (u_int)pagecount;
834 vmd->vmd_segs |= 1UL << m->segind;
840 * Remove blacklisted pages from the physical memory allocator.
842 TAILQ_INIT(&blacklist_head);
843 vm_page_blacklist_load(&list, &listend);
844 vm_page_blacklist_check(list, listend);
846 list = kern_getenv("vm.blacklist");
847 vm_page_blacklist_check(list, NULL);
850 #if VM_NRESERVLEVEL > 0
852 * Initialize the reservation management system.
861 vm_page_reference(vm_page_t m)
864 vm_page_aflag_set(m, PGA_REFERENCED);
868 vm_page_acquire_flags(vm_page_t m, int allocflags)
872 if ((allocflags & (VM_ALLOC_SBUSY | VM_ALLOC_IGN_SBUSY)) != 0)
873 locked = vm_page_trysbusy(m);
875 locked = vm_page_tryxbusy(m);
876 if (locked && (allocflags & VM_ALLOC_WIRED) != 0)
882 vm_page_busy_sleep_flags(vm_object_t object, vm_page_t m, const char *wchan,
886 if ((allocflags & VM_ALLOC_NOWAIT) != 0)
889 * Reference the page before unlocking and
890 * sleeping so that the page daemon is less
891 * likely to reclaim it.
893 if ((allocflags & VM_ALLOC_NOCREAT) == 0)
894 vm_page_aflag_set(m, PGA_REFERENCED);
895 vm_page_busy_sleep(m, wchan, (allocflags &
896 VM_ALLOC_IGN_SBUSY) != 0);
897 VM_OBJECT_WLOCK(object);
898 if ((allocflags & VM_ALLOC_WAITFAIL) != 0)
904 * vm_page_busy_acquire:
906 * Acquire the busy lock as described by VM_ALLOC_* flags. Will loop
907 * and drop the object lock if necessary.
910 vm_page_busy_acquire(vm_page_t m, int allocflags)
916 * The page-specific object must be cached because page
917 * identity can change during the sleep, causing the
918 * re-lock of a different object.
919 * It is assumed that a reference to the object is already
920 * held by the callers.
924 if (vm_page_acquire_flags(m, allocflags))
926 if ((allocflags & VM_ALLOC_NOWAIT) != 0)
929 locked = VM_OBJECT_WOWNED(obj);
932 MPASS(locked || vm_page_wired(m));
933 _vm_page_busy_sleep(obj, m, "vmpba",
934 (allocflags & VM_ALLOC_SBUSY) != 0, locked);
936 VM_OBJECT_WLOCK(obj);
937 if ((allocflags & VM_ALLOC_WAITFAIL) != 0)
939 KASSERT(m->object == obj || m->object == NULL,
940 ("vm_page_busy_acquire: page %p does not belong to %p",
946 * vm_page_busy_downgrade:
948 * Downgrade an exclusive busy page into a single shared busy page.
951 vm_page_busy_downgrade(vm_page_t m)
955 vm_page_assert_xbusied(m);
959 if (atomic_fcmpset_rel_int(&m->busy_lock,
960 &x, VPB_SHARERS_WORD(1)))
963 if ((x & VPB_BIT_WAITERS) != 0)
969 * vm_page_busy_tryupgrade:
971 * Attempt to upgrade a single shared busy into an exclusive busy.
974 vm_page_busy_tryupgrade(vm_page_t m)
978 vm_page_assert_sbusied(m);
981 ce = VPB_CURTHREAD_EXCLUSIVE;
983 if (VPB_SHARERS(x) > 1)
985 KASSERT((x & ~VPB_BIT_WAITERS) == VPB_SHARERS_WORD(1),
986 ("vm_page_busy_tryupgrade: invalid lock state"));
987 if (!atomic_fcmpset_acq_int(&m->busy_lock, &x,
988 ce | (x & VPB_BIT_WAITERS)))
997 * Return a positive value if the page is shared busied, 0 otherwise.
1000 vm_page_sbusied(vm_page_t m)
1005 return ((x & VPB_BIT_SHARED) != 0 && x != VPB_UNBUSIED);
1011 * Shared unbusy a page.
1014 vm_page_sunbusy(vm_page_t m)
1018 vm_page_assert_sbusied(m);
1022 if (VPB_SHARERS(x) > 1) {
1023 if (atomic_fcmpset_int(&m->busy_lock, &x,
1024 x - VPB_ONE_SHARER))
1028 KASSERT((x & ~VPB_BIT_WAITERS) == VPB_SHARERS_WORD(1),
1029 ("vm_page_sunbusy: invalid lock state"));
1030 if (!atomic_fcmpset_rel_int(&m->busy_lock, &x, VPB_UNBUSIED))
1032 if ((x & VPB_BIT_WAITERS) == 0)
1040 * vm_page_busy_sleep:
1042 * Sleep if the page is busy, using the page pointer as wchan.
1043 * This is used to implement the hard-path of busying mechanism.
1045 * If nonshared is true, sleep only if the page is xbusy.
1047 * The object lock must be held on entry and will be released on exit.
1050 vm_page_busy_sleep(vm_page_t m, const char *wmesg, bool nonshared)
1055 VM_OBJECT_ASSERT_LOCKED(obj);
1056 vm_page_lock_assert(m, MA_NOTOWNED);
1058 _vm_page_busy_sleep(obj, m, wmesg, nonshared, true);
1062 _vm_page_busy_sleep(vm_object_t obj, vm_page_t m, const char *wmesg,
1063 bool nonshared, bool locked)
1068 * If the object is busy we must wait for that to drain to zero
1069 * before trying the page again.
1071 if (obj != NULL && vm_object_busied(obj)) {
1073 VM_OBJECT_DROP(obj);
1074 vm_object_busy_wait(obj, wmesg);
1079 if (x == VPB_UNBUSIED || (nonshared && (x & VPB_BIT_SHARED) != 0) ||
1080 ((x & VPB_BIT_WAITERS) == 0 &&
1081 !atomic_cmpset_int(&m->busy_lock, x, x | VPB_BIT_WAITERS))) {
1083 VM_OBJECT_DROP(obj);
1088 VM_OBJECT_DROP(obj);
1090 sleepq_add(m, NULL, wmesg, 0, 0);
1091 sleepq_wait(m, PVM);
1098 * Try to shared busy a page.
1099 * If the operation succeeds 1 is returned otherwise 0.
1100 * The operation never sleeps.
1103 vm_page_trysbusy(vm_page_t m)
1111 if ((x & VPB_BIT_SHARED) == 0)
1114 * Reduce the window for transient busies that will trigger
1115 * false negatives in vm_page_ps_test().
1117 if (obj != NULL && vm_object_busied(obj))
1119 if (atomic_fcmpset_acq_int(&m->busy_lock, &x,
1120 x + VPB_ONE_SHARER))
1124 /* Refetch the object now that we're guaranteed that it is stable. */
1126 if (obj != NULL && vm_object_busied(obj)) {
1136 * Try to exclusive busy a page.
1137 * If the operation succeeds 1 is returned otherwise 0.
1138 * The operation never sleeps.
1141 vm_page_tryxbusy(vm_page_t m)
1145 if (atomic_cmpset_acq_int(&(m)->busy_lock, VPB_UNBUSIED,
1146 VPB_CURTHREAD_EXCLUSIVE) == 0)
1150 if (obj != NULL && vm_object_busied(obj)) {
1158 vm_page_xunbusy_hard_tail(vm_page_t m)
1160 atomic_store_rel_int(&m->busy_lock, VPB_UNBUSIED);
1161 /* Wake the waiter. */
1166 * vm_page_xunbusy_hard:
1168 * Called when unbusy has failed because there is a waiter.
1171 vm_page_xunbusy_hard(vm_page_t m)
1173 vm_page_assert_xbusied(m);
1174 vm_page_xunbusy_hard_tail(m);
1178 vm_page_xunbusy_hard_unchecked(vm_page_t m)
1180 vm_page_assert_xbusied_unchecked(m);
1181 vm_page_xunbusy_hard_tail(m);
1185 * Avoid releasing and reacquiring the same page lock.
1188 vm_page_change_lock(vm_page_t m, struct mtx **mtx)
1192 mtx1 = vm_page_lockptr(m);
1202 * vm_page_unhold_pages:
1204 * Unhold each of the pages that is referenced by the given array.
1207 vm_page_unhold_pages(vm_page_t *ma, int count)
1210 for (; count != 0; count--) {
1211 vm_page_unwire(*ma, PQ_ACTIVE);
1217 PHYS_TO_VM_PAGE(vm_paddr_t pa)
1221 #ifdef VM_PHYSSEG_SPARSE
1222 m = vm_phys_paddr_to_vm_page(pa);
1224 m = vm_phys_fictitious_to_vm_page(pa);
1226 #elif defined(VM_PHYSSEG_DENSE)
1230 if (pi >= first_page && (pi - first_page) < vm_page_array_size) {
1231 m = &vm_page_array[pi - first_page];
1234 return (vm_phys_fictitious_to_vm_page(pa));
1236 #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined."
1243 * Create a fictitious page with the specified physical address and
1244 * memory attribute. The memory attribute is the only the machine-
1245 * dependent aspect of a fictitious page that must be initialized.
1248 vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr)
1252 m = uma_zalloc(fakepg_zone, M_WAITOK | M_ZERO);
1253 vm_page_initfake(m, paddr, memattr);
1258 vm_page_initfake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr)
1261 if ((m->flags & PG_FICTITIOUS) != 0) {
1263 * The page's memattr might have changed since the
1264 * previous initialization. Update the pmap to the
1269 m->phys_addr = paddr;
1270 m->a.queue = PQ_NONE;
1271 /* Fictitious pages don't use "segind". */
1272 m->flags = PG_FICTITIOUS;
1273 /* Fictitious pages don't use "order" or "pool". */
1274 m->oflags = VPO_UNMANAGED;
1275 m->busy_lock = VPB_CURTHREAD_EXCLUSIVE;
1276 /* Fictitious pages are unevictable. */
1280 pmap_page_set_memattr(m, memattr);
1286 * Release a fictitious page.
1289 vm_page_putfake(vm_page_t m)
1292 KASSERT((m->oflags & VPO_UNMANAGED) != 0, ("managed %p", m));
1293 KASSERT((m->flags & PG_FICTITIOUS) != 0,
1294 ("vm_page_putfake: bad page %p", m));
1296 uma_zfree(fakepg_zone, m);
1300 * vm_page_updatefake:
1302 * Update the given fictitious page to the specified physical address and
1306 vm_page_updatefake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr)
1309 KASSERT((m->flags & PG_FICTITIOUS) != 0,
1310 ("vm_page_updatefake: bad page %p", m));
1311 m->phys_addr = paddr;
1312 pmap_page_set_memattr(m, memattr);
1321 vm_page_free(vm_page_t m)
1324 m->flags &= ~PG_ZERO;
1325 vm_page_free_toq(m);
1329 * vm_page_free_zero:
1331 * Free a page to the zerod-pages queue
1334 vm_page_free_zero(vm_page_t m)
1337 m->flags |= PG_ZERO;
1338 vm_page_free_toq(m);
1342 * Unbusy and handle the page queueing for a page from a getpages request that
1343 * was optionally read ahead or behind.
1346 vm_page_readahead_finish(vm_page_t m)
1349 /* We shouldn't put invalid pages on queues. */
1350 KASSERT(!vm_page_none_valid(m), ("%s: %p is invalid", __func__, m));
1353 * Since the page is not the actually needed one, whether it should
1354 * be activated or deactivated is not obvious. Empirical results
1355 * have shown that deactivating the page is usually the best choice,
1356 * unless the page is wanted by another thread.
1359 if ((m->busy_lock & VPB_BIT_WAITERS) != 0)
1360 vm_page_activate(m);
1362 vm_page_deactivate(m);
1364 vm_page_xunbusy_unchecked(m);
1368 * vm_page_sleep_if_busy:
1370 * Sleep and release the object lock if the page is busied.
1371 * Returns TRUE if the thread slept.
1373 * The given page must be unlocked and object containing it must
1377 vm_page_sleep_if_busy(vm_page_t m, const char *msg)
1381 vm_page_lock_assert(m, MA_NOTOWNED);
1382 VM_OBJECT_ASSERT_WLOCKED(m->object);
1385 * The page-specific object must be cached because page
1386 * identity can change during the sleep, causing the
1387 * re-lock of a different object.
1388 * It is assumed that a reference to the object is already
1389 * held by the callers.
1392 if (vm_page_busied(m) || (obj != NULL && obj->busy)) {
1393 vm_page_busy_sleep(m, msg, false);
1394 VM_OBJECT_WLOCK(obj);
1401 * vm_page_sleep_if_xbusy:
1403 * Sleep and release the object lock if the page is xbusied.
1404 * Returns TRUE if the thread slept.
1406 * The given page must be unlocked and object containing it must
1410 vm_page_sleep_if_xbusy(vm_page_t m, const char *msg)
1414 vm_page_lock_assert(m, MA_NOTOWNED);
1415 VM_OBJECT_ASSERT_WLOCKED(m->object);
1418 * The page-specific object must be cached because page
1419 * identity can change during the sleep, causing the
1420 * re-lock of a different object.
1421 * It is assumed that a reference to the object is already
1422 * held by the callers.
1425 if (vm_page_xbusied(m) || (obj != NULL && obj->busy)) {
1426 vm_page_busy_sleep(m, msg, true);
1427 VM_OBJECT_WLOCK(obj);
1434 * vm_page_dirty_KBI: [ internal use only ]
1436 * Set all bits in the page's dirty field.
1438 * The object containing the specified page must be locked if the
1439 * call is made from the machine-independent layer.
1441 * See vm_page_clear_dirty_mask().
1443 * This function should only be called by vm_page_dirty().
1446 vm_page_dirty_KBI(vm_page_t m)
1449 /* Refer to this operation by its public name. */
1450 KASSERT(vm_page_all_valid(m), ("vm_page_dirty: page is invalid!"));
1451 m->dirty = VM_PAGE_BITS_ALL;
1455 * vm_page_insert: [ internal use only ]
1457 * Inserts the given mem entry into the object and object list.
1459 * The object must be locked.
1462 vm_page_insert(vm_page_t m, vm_object_t object, vm_pindex_t pindex)
1466 VM_OBJECT_ASSERT_WLOCKED(object);
1467 mpred = vm_radix_lookup_le(&object->rtree, pindex);
1468 return (vm_page_insert_after(m, object, pindex, mpred));
1472 * vm_page_insert_after:
1474 * Inserts the page "m" into the specified object at offset "pindex".
1476 * The page "mpred" must immediately precede the offset "pindex" within
1477 * the specified object.
1479 * The object must be locked.
1482 vm_page_insert_after(vm_page_t m, vm_object_t object, vm_pindex_t pindex,
1487 VM_OBJECT_ASSERT_WLOCKED(object);
1488 KASSERT(m->object == NULL,
1489 ("vm_page_insert_after: page already inserted"));
1490 if (mpred != NULL) {
1491 KASSERT(mpred->object == object,
1492 ("vm_page_insert_after: object doesn't contain mpred"));
1493 KASSERT(mpred->pindex < pindex,
1494 ("vm_page_insert_after: mpred doesn't precede pindex"));
1495 msucc = TAILQ_NEXT(mpred, listq);
1497 msucc = TAILQ_FIRST(&object->memq);
1499 KASSERT(msucc->pindex > pindex,
1500 ("vm_page_insert_after: msucc doesn't succeed pindex"));
1503 * Record the object/offset pair in this page.
1507 m->ref_count |= VPRC_OBJREF;
1510 * Now link into the object's ordered list of backed pages.
1512 if (vm_radix_insert(&object->rtree, m)) {
1515 m->ref_count &= ~VPRC_OBJREF;
1518 vm_page_insert_radixdone(m, object, mpred);
1523 * vm_page_insert_radixdone:
1525 * Complete page "m" insertion into the specified object after the
1526 * radix trie hooking.
1528 * The page "mpred" must precede the offset "m->pindex" within the
1531 * The object must be locked.
1534 vm_page_insert_radixdone(vm_page_t m, vm_object_t object, vm_page_t mpred)
1537 VM_OBJECT_ASSERT_WLOCKED(object);
1538 KASSERT(object != NULL && m->object == object,
1539 ("vm_page_insert_radixdone: page %p has inconsistent object", m));
1540 KASSERT((m->ref_count & VPRC_OBJREF) != 0,
1541 ("vm_page_insert_radixdone: page %p is missing object ref", m));
1542 if (mpred != NULL) {
1543 KASSERT(mpred->object == object,
1544 ("vm_page_insert_radixdone: object doesn't contain mpred"));
1545 KASSERT(mpred->pindex < m->pindex,
1546 ("vm_page_insert_radixdone: mpred doesn't precede pindex"));
1550 TAILQ_INSERT_AFTER(&object->memq, mpred, m, listq);
1552 TAILQ_INSERT_HEAD(&object->memq, m, listq);
1555 * Show that the object has one more resident page.
1557 object->resident_page_count++;
1560 * Hold the vnode until the last page is released.
1562 if (object->resident_page_count == 1 && object->type == OBJT_VNODE)
1563 vhold(object->handle);
1566 * Since we are inserting a new and possibly dirty page,
1567 * update the object's generation count.
1569 if (pmap_page_is_write_mapped(m))
1570 vm_object_set_writeable_dirty(object);
1574 * Do the work to remove a page from its object. The caller is responsible for
1575 * updating the page's fields to reflect this removal.
1578 vm_page_object_remove(vm_page_t m)
1583 vm_page_assert_xbusied(m);
1585 VM_OBJECT_ASSERT_WLOCKED(object);
1586 KASSERT((m->ref_count & VPRC_OBJREF) != 0,
1587 ("page %p is missing its object ref", m));
1589 /* Deferred free of swap space. */
1590 if ((m->a.flags & PGA_SWAP_FREE) != 0)
1591 vm_pager_page_unswapped(m);
1593 mrem = vm_radix_remove(&object->rtree, m->pindex);
1594 KASSERT(mrem == m, ("removed page %p, expected page %p", mrem, m));
1597 * Now remove from the object's list of backed pages.
1599 TAILQ_REMOVE(&object->memq, m, listq);
1602 * And show that the object has one fewer resident page.
1604 object->resident_page_count--;
1607 * The vnode may now be recycled.
1609 if (object->resident_page_count == 0 && object->type == OBJT_VNODE)
1610 vdrop(object->handle);
1616 * Removes the specified page from its containing object, but does not
1617 * invalidate any backing storage. Returns true if the object's reference
1618 * was the last reference to the page, and false otherwise.
1620 * The object must be locked and the page must be exclusively busied.
1621 * The exclusive busy will be released on return. If this is not the
1622 * final ref and the caller does not hold a wire reference it may not
1623 * continue to access the page.
1626 vm_page_remove(vm_page_t m)
1630 dropped = vm_page_remove_xbusy(m);
1637 * vm_page_remove_xbusy
1639 * Removes the page but leaves the xbusy held. Returns true if this
1640 * removed the final ref and false otherwise.
1643 vm_page_remove_xbusy(vm_page_t m)
1646 vm_page_object_remove(m);
1648 return (vm_page_drop(m, VPRC_OBJREF) == VPRC_OBJREF);
1654 * Returns the page associated with the object/offset
1655 * pair specified; if none is found, NULL is returned.
1657 * The object must be locked.
1660 vm_page_lookup(vm_object_t object, vm_pindex_t pindex)
1663 VM_OBJECT_ASSERT_LOCKED(object);
1664 return (vm_radix_lookup(&object->rtree, pindex));
1668 * vm_page_find_least:
1670 * Returns the page associated with the object with least pindex
1671 * greater than or equal to the parameter pindex, or NULL.
1673 * The object must be locked.
1676 vm_page_find_least(vm_object_t object, vm_pindex_t pindex)
1680 VM_OBJECT_ASSERT_LOCKED(object);
1681 if ((m = TAILQ_FIRST(&object->memq)) != NULL && m->pindex < pindex)
1682 m = vm_radix_lookup_ge(&object->rtree, pindex);
1687 * Returns the given page's successor (by pindex) within the object if it is
1688 * resident; if none is found, NULL is returned.
1690 * The object must be locked.
1693 vm_page_next(vm_page_t m)
1697 VM_OBJECT_ASSERT_LOCKED(m->object);
1698 if ((next = TAILQ_NEXT(m, listq)) != NULL) {
1699 MPASS(next->object == m->object);
1700 if (next->pindex != m->pindex + 1)
1707 * Returns the given page's predecessor (by pindex) within the object if it is
1708 * resident; if none is found, NULL is returned.
1710 * The object must be locked.
1713 vm_page_prev(vm_page_t m)
1717 VM_OBJECT_ASSERT_LOCKED(m->object);
1718 if ((prev = TAILQ_PREV(m, pglist, listq)) != NULL) {
1719 MPASS(prev->object == m->object);
1720 if (prev->pindex != m->pindex - 1)
1727 * Uses the page mnew as a replacement for an existing page at index
1728 * pindex which must be already present in the object.
1730 * Both pages must be exclusively busied on enter. The old page is
1733 * A return value of true means mold is now free. If this is not the
1734 * final ref and the caller does not hold a wire reference it may not
1735 * continue to access the page.
1738 vm_page_replace_hold(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex,
1744 VM_OBJECT_ASSERT_WLOCKED(object);
1745 vm_page_assert_xbusied(mnew);
1746 vm_page_assert_xbusied(mold);
1747 KASSERT(mnew->object == NULL && (mnew->ref_count & VPRC_OBJREF) == 0,
1748 ("vm_page_replace: page %p already in object", mnew));
1751 * This function mostly follows vm_page_insert() and
1752 * vm_page_remove() without the radix, object count and vnode
1753 * dance. Double check such functions for more comments.
1756 mnew->object = object;
1757 mnew->pindex = pindex;
1758 atomic_set_int(&mnew->ref_count, VPRC_OBJREF);
1759 mret = vm_radix_replace(&object->rtree, mnew);
1760 KASSERT(mret == mold,
1761 ("invalid page replacement, mold=%p, mret=%p", mold, mret));
1762 KASSERT((mold->oflags & VPO_UNMANAGED) ==
1763 (mnew->oflags & VPO_UNMANAGED),
1764 ("vm_page_replace: mismatched VPO_UNMANAGED"));
1766 /* Keep the resident page list in sorted order. */
1767 TAILQ_INSERT_AFTER(&object->memq, mold, mnew, listq);
1768 TAILQ_REMOVE(&object->memq, mold, listq);
1769 mold->object = NULL;
1772 * The object's resident_page_count does not change because we have
1773 * swapped one page for another, but the generation count should
1774 * change if the page is dirty.
1776 if (pmap_page_is_write_mapped(mnew))
1777 vm_object_set_writeable_dirty(object);
1778 dropped = vm_page_drop(mold, VPRC_OBJREF) == VPRC_OBJREF;
1779 vm_page_xunbusy(mold);
1785 vm_page_replace(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex,
1789 if (vm_page_replace_hold(mnew, object, pindex, mold))
1796 * Move the given memory entry from its
1797 * current object to the specified target object/offset.
1799 * Note: swap associated with the page must be invalidated by the move. We
1800 * have to do this for several reasons: (1) we aren't freeing the
1801 * page, (2) we are dirtying the page, (3) the VM system is probably
1802 * moving the page from object A to B, and will then later move
1803 * the backing store from A to B and we can't have a conflict.
1805 * Note: we *always* dirty the page. It is necessary both for the
1806 * fact that we moved it, and because we may be invalidating
1809 * The objects must be locked.
1812 vm_page_rename(vm_page_t m, vm_object_t new_object, vm_pindex_t new_pindex)
1817 VM_OBJECT_ASSERT_WLOCKED(new_object);
1819 KASSERT(m->ref_count != 0, ("vm_page_rename: page %p has no refs", m));
1820 mpred = vm_radix_lookup_le(&new_object->rtree, new_pindex);
1821 KASSERT(mpred == NULL || mpred->pindex != new_pindex,
1822 ("vm_page_rename: pindex already renamed"));
1825 * Create a custom version of vm_page_insert() which does not depend
1826 * by m_prev and can cheat on the implementation aspects of the
1830 m->pindex = new_pindex;
1831 if (vm_radix_insert(&new_object->rtree, m)) {
1837 * The operation cannot fail anymore. The removal must happen before
1838 * the listq iterator is tainted.
1841 vm_page_object_remove(m);
1843 /* Return back to the new pindex to complete vm_page_insert(). */
1844 m->pindex = new_pindex;
1845 m->object = new_object;
1847 vm_page_insert_radixdone(m, new_object, mpred);
1855 * Allocate and return a page that is associated with the specified
1856 * object and offset pair. By default, this page is exclusive busied.
1858 * The caller must always specify an allocation class.
1860 * allocation classes:
1861 * VM_ALLOC_NORMAL normal process request
1862 * VM_ALLOC_SYSTEM system *really* needs a page
1863 * VM_ALLOC_INTERRUPT interrupt time request
1865 * optional allocation flags:
1866 * VM_ALLOC_COUNT(number) the number of additional pages that the caller
1867 * intends to allocate
1868 * VM_ALLOC_NOBUSY do not exclusive busy the page
1869 * VM_ALLOC_NODUMP do not include the page in a kernel core dump
1870 * VM_ALLOC_NOOBJ page is not associated with an object and
1871 * should not be exclusive busy
1872 * VM_ALLOC_SBUSY shared busy the allocated page
1873 * VM_ALLOC_WIRED wire the allocated page
1874 * VM_ALLOC_ZERO prefer a zeroed page
1877 vm_page_alloc(vm_object_t object, vm_pindex_t pindex, int req)
1880 return (vm_page_alloc_after(object, pindex, req, object != NULL ?
1881 vm_radix_lookup_le(&object->rtree, pindex) : NULL));
1885 vm_page_alloc_domain(vm_object_t object, vm_pindex_t pindex, int domain,
1889 return (vm_page_alloc_domain_after(object, pindex, domain, req,
1890 object != NULL ? vm_radix_lookup_le(&object->rtree, pindex) :
1895 * Allocate a page in the specified object with the given page index. To
1896 * optimize insertion of the page into the object, the caller must also specifiy
1897 * the resident page in the object with largest index smaller than the given
1898 * page index, or NULL if no such page exists.
1901 vm_page_alloc_after(vm_object_t object, vm_pindex_t pindex,
1902 int req, vm_page_t mpred)
1904 struct vm_domainset_iter di;
1908 vm_domainset_iter_page_init(&di, object, pindex, &domain, &req);
1910 m = vm_page_alloc_domain_after(object, pindex, domain, req,
1914 } while (vm_domainset_iter_page(&di, object, &domain) == 0);
1920 * Returns true if the number of free pages exceeds the minimum
1921 * for the request class and false otherwise.
1924 _vm_domain_allocate(struct vm_domain *vmd, int req_class, int npages)
1926 u_int limit, old, new;
1928 if (req_class == VM_ALLOC_INTERRUPT)
1930 else if (req_class == VM_ALLOC_SYSTEM)
1931 limit = vmd->vmd_interrupt_free_min;
1933 limit = vmd->vmd_free_reserved;
1936 * Attempt to reserve the pages. Fail if we're below the limit.
1939 old = vmd->vmd_free_count;
1944 } while (atomic_fcmpset_int(&vmd->vmd_free_count, &old, new) == 0);
1946 /* Wake the page daemon if we've crossed the threshold. */
1947 if (vm_paging_needed(vmd, new) && !vm_paging_needed(vmd, old))
1948 pagedaemon_wakeup(vmd->vmd_domain);
1950 /* Only update bitsets on transitions. */
1951 if ((old >= vmd->vmd_free_min && new < vmd->vmd_free_min) ||
1952 (old >= vmd->vmd_free_severe && new < vmd->vmd_free_severe))
1959 vm_domain_allocate(struct vm_domain *vmd, int req, int npages)
1964 * The page daemon is allowed to dig deeper into the free page list.
1966 req_class = req & VM_ALLOC_CLASS_MASK;
1967 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT)
1968 req_class = VM_ALLOC_SYSTEM;
1969 return (_vm_domain_allocate(vmd, req_class, npages));
1973 vm_page_alloc_domain_after(vm_object_t object, vm_pindex_t pindex, int domain,
1974 int req, vm_page_t mpred)
1976 struct vm_domain *vmd;
1980 KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) &&
1981 (object != NULL || (req & VM_ALLOC_SBUSY) == 0) &&
1982 ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) !=
1983 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)),
1984 ("inconsistent object(%p)/req(%x)", object, req));
1985 KASSERT(object == NULL || (req & VM_ALLOC_WAITOK) == 0,
1986 ("Can't sleep and retry object insertion."));
1987 KASSERT(mpred == NULL || mpred->pindex < pindex,
1988 ("mpred %p doesn't precede pindex 0x%jx", mpred,
1989 (uintmax_t)pindex));
1991 VM_OBJECT_ASSERT_WLOCKED(object);
1995 pool = object != NULL ? VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT;
1997 #if VM_NRESERVLEVEL > 0
1999 * Can we allocate the page from a reservation?
2001 if (vm_object_reserv(object) &&
2002 (m = vm_reserv_alloc_page(object, pindex, domain, req, mpred)) !=
2004 domain = vm_phys_domain(m);
2005 vmd = VM_DOMAIN(domain);
2009 vmd = VM_DOMAIN(domain);
2010 if (vmd->vmd_pgcache[pool].zone != NULL) {
2011 m = uma_zalloc(vmd->vmd_pgcache[pool].zone, M_NOWAIT);
2013 flags |= PG_PCPU_CACHE;
2017 if (vm_domain_allocate(vmd, req, 1)) {
2019 * If not, allocate it from the free page queues.
2021 vm_domain_free_lock(vmd);
2022 m = vm_phys_alloc_pages(domain, pool, 0);
2023 vm_domain_free_unlock(vmd);
2025 vm_domain_freecnt_inc(vmd, 1);
2026 #if VM_NRESERVLEVEL > 0
2027 if (vm_reserv_reclaim_inactive(domain))
2034 * Not allocatable, give up.
2036 if (vm_domain_alloc_fail(vmd, object, req))
2042 * At this point we had better have found a good page.
2046 vm_page_alloc_check(m);
2049 * Initialize the page. Only the PG_ZERO flag is inherited.
2051 if ((req & VM_ALLOC_ZERO) != 0)
2052 flags |= (m->flags & PG_ZERO);
2053 if ((req & VM_ALLOC_NODUMP) != 0)
2057 m->oflags = object == NULL || (object->flags & OBJ_UNMANAGED) != 0 ?
2059 m->busy_lock = VPB_UNBUSIED;
2060 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ | VM_ALLOC_SBUSY)) == 0)
2061 m->busy_lock = VPB_CURTHREAD_EXCLUSIVE;
2062 if ((req & VM_ALLOC_SBUSY) != 0)
2063 m->busy_lock = VPB_SHARERS_WORD(1);
2064 if (req & VM_ALLOC_WIRED) {
2066 * The page lock is not required for wiring a page until that
2067 * page is inserted into the object.
2074 if (object != NULL) {
2075 if (vm_page_insert_after(m, object, pindex, mpred)) {
2076 if (req & VM_ALLOC_WIRED) {
2080 KASSERT(m->object == NULL, ("page %p has object", m));
2081 m->oflags = VPO_UNMANAGED;
2082 m->busy_lock = VPB_UNBUSIED;
2083 /* Don't change PG_ZERO. */
2084 vm_page_free_toq(m);
2085 if (req & VM_ALLOC_WAITFAIL) {
2086 VM_OBJECT_WUNLOCK(object);
2088 VM_OBJECT_WLOCK(object);
2093 /* Ignore device objects; the pager sets "memattr" for them. */
2094 if (object->memattr != VM_MEMATTR_DEFAULT &&
2095 (object->flags & OBJ_FICTITIOUS) == 0)
2096 pmap_page_set_memattr(m, object->memattr);
2104 * vm_page_alloc_contig:
2106 * Allocate a contiguous set of physical pages of the given size "npages"
2107 * from the free lists. All of the physical pages must be at or above
2108 * the given physical address "low" and below the given physical address
2109 * "high". The given value "alignment" determines the alignment of the
2110 * first physical page in the set. If the given value "boundary" is
2111 * non-zero, then the set of physical pages cannot cross any physical
2112 * address boundary that is a multiple of that value. Both "alignment"
2113 * and "boundary" must be a power of two.
2115 * If the specified memory attribute, "memattr", is VM_MEMATTR_DEFAULT,
2116 * then the memory attribute setting for the physical pages is configured
2117 * to the object's memory attribute setting. Otherwise, the memory
2118 * attribute setting for the physical pages is configured to "memattr",
2119 * overriding the object's memory attribute setting. However, if the
2120 * object's memory attribute setting is not VM_MEMATTR_DEFAULT, then the
2121 * memory attribute setting for the physical pages cannot be configured
2122 * to VM_MEMATTR_DEFAULT.
2124 * The specified object may not contain fictitious pages.
2126 * The caller must always specify an allocation class.
2128 * allocation classes:
2129 * VM_ALLOC_NORMAL normal process request
2130 * VM_ALLOC_SYSTEM system *really* needs a page
2131 * VM_ALLOC_INTERRUPT interrupt time request
2133 * optional allocation flags:
2134 * VM_ALLOC_NOBUSY do not exclusive busy the page
2135 * VM_ALLOC_NODUMP do not include the page in a kernel core dump
2136 * VM_ALLOC_NOOBJ page is not associated with an object and
2137 * should not be exclusive busy
2138 * VM_ALLOC_SBUSY shared busy the allocated page
2139 * VM_ALLOC_WIRED wire the allocated page
2140 * VM_ALLOC_ZERO prefer a zeroed page
2143 vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req,
2144 u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment,
2145 vm_paddr_t boundary, vm_memattr_t memattr)
2147 struct vm_domainset_iter di;
2151 vm_domainset_iter_page_init(&di, object, pindex, &domain, &req);
2153 m = vm_page_alloc_contig_domain(object, pindex, domain, req,
2154 npages, low, high, alignment, boundary, memattr);
2157 } while (vm_domainset_iter_page(&di, object, &domain) == 0);
2163 vm_page_alloc_contig_domain(vm_object_t object, vm_pindex_t pindex, int domain,
2164 int req, u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment,
2165 vm_paddr_t boundary, vm_memattr_t memattr)
2167 struct vm_domain *vmd;
2168 vm_page_t m, m_ret, mpred;
2169 u_int busy_lock, flags, oflags;
2171 mpred = NULL; /* XXX: pacify gcc */
2172 KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) &&
2173 (object != NULL || (req & VM_ALLOC_SBUSY) == 0) &&
2174 ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) !=
2175 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)),
2176 ("vm_page_alloc_contig: inconsistent object(%p)/req(%x)", object,
2178 KASSERT(object == NULL || (req & VM_ALLOC_WAITOK) == 0,
2179 ("Can't sleep and retry object insertion."));
2180 if (object != NULL) {
2181 VM_OBJECT_ASSERT_WLOCKED(object);
2182 KASSERT((object->flags & OBJ_FICTITIOUS) == 0,
2183 ("vm_page_alloc_contig: object %p has fictitious pages",
2186 KASSERT(npages > 0, ("vm_page_alloc_contig: npages is zero"));
2188 if (object != NULL) {
2189 mpred = vm_radix_lookup_le(&object->rtree, pindex);
2190 KASSERT(mpred == NULL || mpred->pindex != pindex,
2191 ("vm_page_alloc_contig: pindex already allocated"));
2195 * Can we allocate the pages without the number of free pages falling
2196 * below the lower bound for the allocation class?
2200 #if VM_NRESERVLEVEL > 0
2202 * Can we allocate the pages from a reservation?
2204 if (vm_object_reserv(object) &&
2205 (m_ret = vm_reserv_alloc_contig(object, pindex, domain, req,
2206 mpred, npages, low, high, alignment, boundary)) != NULL) {
2207 domain = vm_phys_domain(m_ret);
2208 vmd = VM_DOMAIN(domain);
2212 vmd = VM_DOMAIN(domain);
2213 if (vm_domain_allocate(vmd, req, npages)) {
2215 * allocate them from the free page queues.
2217 vm_domain_free_lock(vmd);
2218 m_ret = vm_phys_alloc_contig(domain, npages, low, high,
2219 alignment, boundary);
2220 vm_domain_free_unlock(vmd);
2221 if (m_ret == NULL) {
2222 vm_domain_freecnt_inc(vmd, npages);
2223 #if VM_NRESERVLEVEL > 0
2224 if (vm_reserv_reclaim_contig(domain, npages, low,
2225 high, alignment, boundary))
2230 if (m_ret == NULL) {
2231 if (vm_domain_alloc_fail(vmd, object, req))
2235 #if VM_NRESERVLEVEL > 0
2238 for (m = m_ret; m < &m_ret[npages]; m++) {
2240 vm_page_alloc_check(m);
2244 * Initialize the pages. Only the PG_ZERO flag is inherited.
2247 if ((req & VM_ALLOC_ZERO) != 0)
2249 if ((req & VM_ALLOC_NODUMP) != 0)
2251 oflags = object == NULL || (object->flags & OBJ_UNMANAGED) != 0 ?
2253 busy_lock = VPB_UNBUSIED;
2254 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ | VM_ALLOC_SBUSY)) == 0)
2255 busy_lock = VPB_CURTHREAD_EXCLUSIVE;
2256 if ((req & VM_ALLOC_SBUSY) != 0)
2257 busy_lock = VPB_SHARERS_WORD(1);
2258 if ((req & VM_ALLOC_WIRED) != 0)
2259 vm_wire_add(npages);
2260 if (object != NULL) {
2261 if (object->memattr != VM_MEMATTR_DEFAULT &&
2262 memattr == VM_MEMATTR_DEFAULT)
2263 memattr = object->memattr;
2265 for (m = m_ret; m < &m_ret[npages]; m++) {
2267 m->flags = (m->flags | PG_NODUMP) & flags;
2268 m->busy_lock = busy_lock;
2269 if ((req & VM_ALLOC_WIRED) != 0)
2273 if (object != NULL) {
2274 if (vm_page_insert_after(m, object, pindex, mpred)) {
2275 if ((req & VM_ALLOC_WIRED) != 0)
2276 vm_wire_sub(npages);
2277 KASSERT(m->object == NULL,
2278 ("page %p has object", m));
2280 for (m = m_ret; m < &m_ret[npages]; m++) {
2282 (req & VM_ALLOC_WIRED) != 0)
2284 m->oflags = VPO_UNMANAGED;
2285 m->busy_lock = VPB_UNBUSIED;
2286 /* Don't change PG_ZERO. */
2287 vm_page_free_toq(m);
2289 if (req & VM_ALLOC_WAITFAIL) {
2290 VM_OBJECT_WUNLOCK(object);
2292 VM_OBJECT_WLOCK(object);
2299 if (memattr != VM_MEMATTR_DEFAULT)
2300 pmap_page_set_memattr(m, memattr);
2307 * Check a page that has been freshly dequeued from a freelist.
2310 vm_page_alloc_check(vm_page_t m)
2313 KASSERT(m->object == NULL, ("page %p has object", m));
2314 KASSERT(m->a.queue == PQ_NONE &&
2315 (m->a.flags & PGA_QUEUE_STATE_MASK) == 0,
2316 ("page %p has unexpected queue %d, flags %#x",
2317 m, m->a.queue, (m->a.flags & PGA_QUEUE_STATE_MASK)));
2318 KASSERT(m->ref_count == 0, ("page %p has references", m));
2319 KASSERT(!vm_page_busied(m), ("page %p is busy", m));
2320 KASSERT(m->dirty == 0, ("page %p is dirty", m));
2321 KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT,
2322 ("page %p has unexpected memattr %d",
2323 m, pmap_page_get_memattr(m)));
2324 KASSERT(m->valid == 0, ("free page %p is valid", m));
2328 * vm_page_alloc_freelist:
2330 * Allocate a physical page from the specified free page list.
2332 * The caller must always specify an allocation class.
2334 * allocation classes:
2335 * VM_ALLOC_NORMAL normal process request
2336 * VM_ALLOC_SYSTEM system *really* needs a page
2337 * VM_ALLOC_INTERRUPT interrupt time request
2339 * optional allocation flags:
2340 * VM_ALLOC_COUNT(number) the number of additional pages that the caller
2341 * intends to allocate
2342 * VM_ALLOC_WIRED wire the allocated page
2343 * VM_ALLOC_ZERO prefer a zeroed page
2346 vm_page_alloc_freelist(int freelist, int req)
2348 struct vm_domainset_iter di;
2352 vm_domainset_iter_page_init(&di, NULL, 0, &domain, &req);
2354 m = vm_page_alloc_freelist_domain(domain, freelist, req);
2357 } while (vm_domainset_iter_page(&di, NULL, &domain) == 0);
2363 vm_page_alloc_freelist_domain(int domain, int freelist, int req)
2365 struct vm_domain *vmd;
2370 vmd = VM_DOMAIN(domain);
2372 if (vm_domain_allocate(vmd, req, 1)) {
2373 vm_domain_free_lock(vmd);
2374 m = vm_phys_alloc_freelist_pages(domain, freelist,
2375 VM_FREEPOOL_DIRECT, 0);
2376 vm_domain_free_unlock(vmd);
2378 vm_domain_freecnt_inc(vmd, 1);
2381 if (vm_domain_alloc_fail(vmd, NULL, req))
2386 vm_page_alloc_check(m);
2389 * Initialize the page. Only the PG_ZERO flag is inherited.
2393 if ((req & VM_ALLOC_ZERO) != 0)
2396 if ((req & VM_ALLOC_WIRED) != 0) {
2398 * The page lock is not required for wiring a page that does
2399 * not belong to an object.
2404 /* Unmanaged pages don't use "act_count". */
2405 m->oflags = VPO_UNMANAGED;
2410 vm_page_zone_import(void *arg, void **store, int cnt, int domain, int flags)
2412 struct vm_domain *vmd;
2413 struct vm_pgcache *pgcache;
2417 vmd = VM_DOMAIN(pgcache->domain);
2420 * The page daemon should avoid creating extra memory pressure since its
2421 * main purpose is to replenish the store of free pages.
2423 if (vmd->vmd_severeset || curproc == pageproc ||
2424 !_vm_domain_allocate(vmd, VM_ALLOC_NORMAL, cnt))
2426 domain = vmd->vmd_domain;
2427 vm_domain_free_lock(vmd);
2428 i = vm_phys_alloc_npages(domain, pgcache->pool, cnt,
2429 (vm_page_t *)store);
2430 vm_domain_free_unlock(vmd);
2432 vm_domain_freecnt_inc(vmd, cnt - i);
2438 vm_page_zone_release(void *arg, void **store, int cnt)
2440 struct vm_domain *vmd;
2441 struct vm_pgcache *pgcache;
2446 vmd = VM_DOMAIN(pgcache->domain);
2447 vm_domain_free_lock(vmd);
2448 for (i = 0; i < cnt; i++) {
2449 m = (vm_page_t)store[i];
2450 vm_phys_free_pages(m, 0);
2452 vm_domain_free_unlock(vmd);
2453 vm_domain_freecnt_inc(vmd, cnt);
2456 #define VPSC_ANY 0 /* No restrictions. */
2457 #define VPSC_NORESERV 1 /* Skip reservations; implies VPSC_NOSUPER. */
2458 #define VPSC_NOSUPER 2 /* Skip superpages. */
2461 * vm_page_scan_contig:
2463 * Scan vm_page_array[] between the specified entries "m_start" and
2464 * "m_end" for a run of contiguous physical pages that satisfy the
2465 * specified conditions, and return the lowest page in the run. The
2466 * specified "alignment" determines the alignment of the lowest physical
2467 * page in the run. If the specified "boundary" is non-zero, then the
2468 * run of physical pages cannot span a physical address that is a
2469 * multiple of "boundary".
2471 * "m_end" is never dereferenced, so it need not point to a vm_page
2472 * structure within vm_page_array[].
2474 * "npages" must be greater than zero. "m_start" and "m_end" must not
2475 * span a hole (or discontiguity) in the physical address space. Both
2476 * "alignment" and "boundary" must be a power of two.
2479 vm_page_scan_contig(u_long npages, vm_page_t m_start, vm_page_t m_end,
2480 u_long alignment, vm_paddr_t boundary, int options)
2486 #if VM_NRESERVLEVEL > 0
2489 int m_inc, order, run_ext, run_len;
2491 KASSERT(npages > 0, ("npages is 0"));
2492 KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
2493 KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
2497 for (m = m_start; m < m_end && run_len < npages; m += m_inc) {
2498 KASSERT((m->flags & PG_MARKER) == 0,
2499 ("page %p is PG_MARKER", m));
2500 KASSERT((m->flags & PG_FICTITIOUS) == 0 || m->ref_count >= 1,
2501 ("fictitious page %p has invalid ref count", m));
2504 * If the current page would be the start of a run, check its
2505 * physical address against the end, alignment, and boundary
2506 * conditions. If it doesn't satisfy these conditions, either
2507 * terminate the scan or advance to the next page that
2508 * satisfies the failed condition.
2511 KASSERT(m_run == NULL, ("m_run != NULL"));
2512 if (m + npages > m_end)
2514 pa = VM_PAGE_TO_PHYS(m);
2515 if ((pa & (alignment - 1)) != 0) {
2516 m_inc = atop(roundup2(pa, alignment) - pa);
2519 if (rounddown2(pa ^ (pa + ptoa(npages) - 1),
2521 m_inc = atop(roundup2(pa, boundary) - pa);
2525 KASSERT(m_run != NULL, ("m_run == NULL"));
2527 vm_page_change_lock(m, &m_mtx);
2530 if (vm_page_wired(m))
2532 #if VM_NRESERVLEVEL > 0
2533 else if ((level = vm_reserv_level(m)) >= 0 &&
2534 (options & VPSC_NORESERV) != 0) {
2536 /* Advance to the end of the reservation. */
2537 pa = VM_PAGE_TO_PHYS(m);
2538 m_inc = atop(roundup2(pa + 1, vm_reserv_size(level)) -
2542 else if ((object = m->object) != NULL) {
2544 * The page is considered eligible for relocation if
2545 * and only if it could be laundered or reclaimed by
2548 if (!VM_OBJECT_TRYRLOCK(object)) {
2550 VM_OBJECT_RLOCK(object);
2552 if (m->object != object) {
2554 * The page may have been freed.
2556 VM_OBJECT_RUNLOCK(object);
2560 /* Don't care: PG_NODUMP, PG_ZERO. */
2561 if (object->type != OBJT_DEFAULT &&
2562 object->type != OBJT_SWAP &&
2563 object->type != OBJT_VNODE) {
2565 #if VM_NRESERVLEVEL > 0
2566 } else if ((options & VPSC_NOSUPER) != 0 &&
2567 (level = vm_reserv_level_iffullpop(m)) >= 0) {
2569 /* Advance to the end of the superpage. */
2570 pa = VM_PAGE_TO_PHYS(m);
2571 m_inc = atop(roundup2(pa + 1,
2572 vm_reserv_size(level)) - pa);
2574 } else if (object->memattr == VM_MEMATTR_DEFAULT &&
2575 vm_page_queue(m) != PQ_NONE && !vm_page_busied(m) &&
2576 !vm_page_wired(m)) {
2578 * The page is allocated but eligible for
2579 * relocation. Extend the current run by one
2582 KASSERT(pmap_page_get_memattr(m) ==
2584 ("page %p has an unexpected memattr", m));
2585 KASSERT((m->oflags & (VPO_SWAPINPROG |
2586 VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0,
2587 ("page %p has unexpected oflags", m));
2588 /* Don't care: PGA_NOSYNC. */
2592 VM_OBJECT_RUNLOCK(object);
2593 #if VM_NRESERVLEVEL > 0
2594 } else if (level >= 0) {
2596 * The page is reserved but not yet allocated. In
2597 * other words, it is still free. Extend the current
2602 } else if ((order = m->order) < VM_NFREEORDER) {
2604 * The page is enqueued in the physical memory
2605 * allocator's free page queues. Moreover, it is the
2606 * first page in a power-of-two-sized run of
2607 * contiguous free pages. Add these pages to the end
2608 * of the current run, and jump ahead.
2610 run_ext = 1 << order;
2614 * Skip the page for one of the following reasons: (1)
2615 * It is enqueued in the physical memory allocator's
2616 * free page queues. However, it is not the first
2617 * page in a run of contiguous free pages. (This case
2618 * rarely occurs because the scan is performed in
2619 * ascending order.) (2) It is not reserved, and it is
2620 * transitioning from free to allocated. (Conversely,
2621 * the transition from allocated to free for managed
2622 * pages is blocked by the page lock.) (3) It is
2623 * allocated but not contained by an object and not
2624 * wired, e.g., allocated by Xen's balloon driver.
2630 * Extend or reset the current run of pages.
2645 if (run_len >= npages)
2651 * vm_page_reclaim_run:
2653 * Try to relocate each of the allocated virtual pages within the
2654 * specified run of physical pages to a new physical address. Free the
2655 * physical pages underlying the relocated virtual pages. A virtual page
2656 * is relocatable if and only if it could be laundered or reclaimed by
2657 * the page daemon. Whenever possible, a virtual page is relocated to a
2658 * physical address above "high".
2660 * Returns 0 if every physical page within the run was already free or
2661 * just freed by a successful relocation. Otherwise, returns a non-zero
2662 * value indicating why the last attempt to relocate a virtual page was
2665 * "req_class" must be an allocation class.
2668 vm_page_reclaim_run(int req_class, int domain, u_long npages, vm_page_t m_run,
2671 struct vm_domain *vmd;
2673 struct spglist free;
2676 vm_page_t m, m_end, m_new;
2677 int error, order, req;
2679 KASSERT((req_class & VM_ALLOC_CLASS_MASK) == req_class,
2680 ("req_class is not an allocation class"));
2684 m_end = m_run + npages;
2686 for (; error == 0 && m < m_end; m++) {
2687 KASSERT((m->flags & (PG_FICTITIOUS | PG_MARKER)) == 0,
2688 ("page %p is PG_FICTITIOUS or PG_MARKER", m));
2691 * Avoid releasing and reacquiring the same page lock.
2693 vm_page_change_lock(m, &m_mtx);
2696 * Racily check for wirings. Races are handled below.
2698 if (vm_page_wired(m))
2700 else if ((object = m->object) != NULL) {
2702 * The page is relocated if and only if it could be
2703 * laundered or reclaimed by the page daemon.
2705 if (!VM_OBJECT_TRYWLOCK(object)) {
2707 VM_OBJECT_WLOCK(object);
2709 if (m->object != object) {
2711 * The page may have been freed.
2713 VM_OBJECT_WUNLOCK(object);
2717 /* Don't care: PG_NODUMP, PG_ZERO. */
2718 if (object->type != OBJT_DEFAULT &&
2719 object->type != OBJT_SWAP &&
2720 object->type != OBJT_VNODE)
2722 else if (object->memattr != VM_MEMATTR_DEFAULT)
2724 else if (vm_page_queue(m) != PQ_NONE &&
2725 vm_page_tryxbusy(m) != 0) {
2726 if (vm_page_wired(m)) {
2731 KASSERT(pmap_page_get_memattr(m) ==
2733 ("page %p has an unexpected memattr", m));
2734 KASSERT(m->oflags == 0,
2735 ("page %p has unexpected oflags", m));
2736 /* Don't care: PGA_NOSYNC. */
2737 if (!vm_page_none_valid(m)) {
2739 * First, try to allocate a new page
2740 * that is above "high". Failing
2741 * that, try to allocate a new page
2742 * that is below "m_run". Allocate
2743 * the new page between the end of
2744 * "m_run" and "high" only as a last
2747 req = req_class | VM_ALLOC_NOOBJ;
2748 if ((m->flags & PG_NODUMP) != 0)
2749 req |= VM_ALLOC_NODUMP;
2750 if (trunc_page(high) !=
2751 ~(vm_paddr_t)PAGE_MASK) {
2752 m_new = vm_page_alloc_contig(
2757 VM_MEMATTR_DEFAULT);
2760 if (m_new == NULL) {
2761 pa = VM_PAGE_TO_PHYS(m_run);
2762 m_new = vm_page_alloc_contig(
2764 0, pa - 1, PAGE_SIZE, 0,
2765 VM_MEMATTR_DEFAULT);
2767 if (m_new == NULL) {
2769 m_new = vm_page_alloc_contig(
2771 pa, high, PAGE_SIZE, 0,
2772 VM_MEMATTR_DEFAULT);
2774 if (m_new == NULL) {
2781 * Unmap the page and check for new
2782 * wirings that may have been acquired
2783 * through a pmap lookup.
2785 if (object->ref_count != 0 &&
2786 !vm_page_try_remove_all(m)) {
2787 vm_page_free(m_new);
2793 * Replace "m" with the new page. For
2794 * vm_page_replace(), "m" must be busy
2795 * and dequeued. Finally, change "m"
2796 * as if vm_page_free() was called.
2798 m_new->a.flags = m->a.flags &
2799 ~PGA_QUEUE_STATE_MASK;
2800 KASSERT(m_new->oflags == VPO_UNMANAGED,
2801 ("page %p is managed", m_new));
2803 pmap_copy_page(m, m_new);
2804 m_new->valid = m->valid;
2805 m_new->dirty = m->dirty;
2806 m->flags &= ~PG_ZERO;
2808 if (vm_page_replace_hold(m_new, object,
2810 vm_page_free_prep(m))
2811 SLIST_INSERT_HEAD(&free, m,
2815 * The new page must be deactivated
2816 * before the object is unlocked.
2818 vm_page_change_lock(m_new, &m_mtx);
2819 vm_page_deactivate(m_new);
2821 m->flags &= ~PG_ZERO;
2823 if (vm_page_free_prep(m))
2824 SLIST_INSERT_HEAD(&free, m,
2826 KASSERT(m->dirty == 0,
2827 ("page %p is dirty", m));
2832 VM_OBJECT_WUNLOCK(object);
2834 MPASS(vm_phys_domain(m) == domain);
2835 vmd = VM_DOMAIN(domain);
2836 vm_domain_free_lock(vmd);
2838 if (order < VM_NFREEORDER) {
2840 * The page is enqueued in the physical memory
2841 * allocator's free page queues. Moreover, it
2842 * is the first page in a power-of-two-sized
2843 * run of contiguous free pages. Jump ahead
2844 * to the last page within that run, and
2845 * continue from there.
2847 m += (1 << order) - 1;
2849 #if VM_NRESERVLEVEL > 0
2850 else if (vm_reserv_is_page_free(m))
2853 vm_domain_free_unlock(vmd);
2854 if (order == VM_NFREEORDER)
2860 if ((m = SLIST_FIRST(&free)) != NULL) {
2863 vmd = VM_DOMAIN(domain);
2865 vm_domain_free_lock(vmd);
2867 MPASS(vm_phys_domain(m) == domain);
2868 SLIST_REMOVE_HEAD(&free, plinks.s.ss);
2869 vm_phys_free_pages(m, 0);
2871 } while ((m = SLIST_FIRST(&free)) != NULL);
2872 vm_domain_free_unlock(vmd);
2873 vm_domain_freecnt_inc(vmd, cnt);
2880 CTASSERT(powerof2(NRUNS));
2882 #define RUN_INDEX(count) ((count) & (NRUNS - 1))
2884 #define MIN_RECLAIM 8
2887 * vm_page_reclaim_contig:
2889 * Reclaim allocated, contiguous physical memory satisfying the specified
2890 * conditions by relocating the virtual pages using that physical memory.
2891 * Returns true if reclamation is successful and false otherwise. Since
2892 * relocation requires the allocation of physical pages, reclamation may
2893 * fail due to a shortage of free pages. When reclamation fails, callers
2894 * are expected to perform vm_wait() before retrying a failed allocation
2895 * operation, e.g., vm_page_alloc_contig().
2897 * The caller must always specify an allocation class through "req".
2899 * allocation classes:
2900 * VM_ALLOC_NORMAL normal process request
2901 * VM_ALLOC_SYSTEM system *really* needs a page
2902 * VM_ALLOC_INTERRUPT interrupt time request
2904 * The optional allocation flags are ignored.
2906 * "npages" must be greater than zero. Both "alignment" and "boundary"
2907 * must be a power of two.
2910 vm_page_reclaim_contig_domain(int domain, int req, u_long npages,
2911 vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary)
2913 struct vm_domain *vmd;
2914 vm_paddr_t curr_low;
2915 vm_page_t m_run, m_runs[NRUNS];
2916 u_long count, reclaimed;
2917 int error, i, options, req_class;
2919 KASSERT(npages > 0, ("npages is 0"));
2920 KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
2921 KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
2922 req_class = req & VM_ALLOC_CLASS_MASK;
2925 * The page daemon is allowed to dig deeper into the free page list.
2927 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT)
2928 req_class = VM_ALLOC_SYSTEM;
2931 * Return if the number of free pages cannot satisfy the requested
2934 vmd = VM_DOMAIN(domain);
2935 count = vmd->vmd_free_count;
2936 if (count < npages + vmd->vmd_free_reserved || (count < npages +
2937 vmd->vmd_interrupt_free_min && req_class == VM_ALLOC_SYSTEM) ||
2938 (count < npages && req_class == VM_ALLOC_INTERRUPT))
2942 * Scan up to three times, relaxing the restrictions ("options") on
2943 * the reclamation of reservations and superpages each time.
2945 for (options = VPSC_NORESERV;;) {
2947 * Find the highest runs that satisfy the given constraints
2948 * and restrictions, and record them in "m_runs".
2953 m_run = vm_phys_scan_contig(domain, npages, curr_low,
2954 high, alignment, boundary, options);
2957 curr_low = VM_PAGE_TO_PHYS(m_run) + ptoa(npages);
2958 m_runs[RUN_INDEX(count)] = m_run;
2963 * Reclaim the highest runs in LIFO (descending) order until
2964 * the number of reclaimed pages, "reclaimed", is at least
2965 * MIN_RECLAIM. Reset "reclaimed" each time because each
2966 * reclamation is idempotent, and runs will (likely) recur
2967 * from one scan to the next as restrictions are relaxed.
2970 for (i = 0; count > 0 && i < NRUNS; i++) {
2972 m_run = m_runs[RUN_INDEX(count)];
2973 error = vm_page_reclaim_run(req_class, domain, npages,
2976 reclaimed += npages;
2977 if (reclaimed >= MIN_RECLAIM)
2983 * Either relax the restrictions on the next scan or return if
2984 * the last scan had no restrictions.
2986 if (options == VPSC_NORESERV)
2987 options = VPSC_NOSUPER;
2988 else if (options == VPSC_NOSUPER)
2990 else if (options == VPSC_ANY)
2991 return (reclaimed != 0);
2996 vm_page_reclaim_contig(int req, u_long npages, vm_paddr_t low, vm_paddr_t high,
2997 u_long alignment, vm_paddr_t boundary)
2999 struct vm_domainset_iter di;
3003 vm_domainset_iter_page_init(&di, NULL, 0, &domain, &req);
3005 ret = vm_page_reclaim_contig_domain(domain, req, npages, low,
3006 high, alignment, boundary);
3009 } while (vm_domainset_iter_page(&di, NULL, &domain) == 0);
3015 * Set the domain in the appropriate page level domainset.
3018 vm_domain_set(struct vm_domain *vmd)
3021 mtx_lock(&vm_domainset_lock);
3022 if (!vmd->vmd_minset && vm_paging_min(vmd)) {
3023 vmd->vmd_minset = 1;
3024 DOMAINSET_SET(vmd->vmd_domain, &vm_min_domains);
3026 if (!vmd->vmd_severeset && vm_paging_severe(vmd)) {
3027 vmd->vmd_severeset = 1;
3028 DOMAINSET_SET(vmd->vmd_domain, &vm_severe_domains);
3030 mtx_unlock(&vm_domainset_lock);
3034 * Clear the domain from the appropriate page level domainset.
3037 vm_domain_clear(struct vm_domain *vmd)
3040 mtx_lock(&vm_domainset_lock);
3041 if (vmd->vmd_minset && !vm_paging_min(vmd)) {
3042 vmd->vmd_minset = 0;
3043 DOMAINSET_CLR(vmd->vmd_domain, &vm_min_domains);
3044 if (vm_min_waiters != 0) {
3046 wakeup(&vm_min_domains);
3049 if (vmd->vmd_severeset && !vm_paging_severe(vmd)) {
3050 vmd->vmd_severeset = 0;
3051 DOMAINSET_CLR(vmd->vmd_domain, &vm_severe_domains);
3052 if (vm_severe_waiters != 0) {
3053 vm_severe_waiters = 0;
3054 wakeup(&vm_severe_domains);
3059 * If pageout daemon needs pages, then tell it that there are
3062 if (vmd->vmd_pageout_pages_needed &&
3063 vmd->vmd_free_count >= vmd->vmd_pageout_free_min) {
3064 wakeup(&vmd->vmd_pageout_pages_needed);
3065 vmd->vmd_pageout_pages_needed = 0;
3068 /* See comments in vm_wait_doms(). */
3069 if (vm_pageproc_waiters) {
3070 vm_pageproc_waiters = 0;
3071 wakeup(&vm_pageproc_waiters);
3073 mtx_unlock(&vm_domainset_lock);
3077 * Wait for free pages to exceed the min threshold globally.
3083 mtx_lock(&vm_domainset_lock);
3084 while (vm_page_count_min()) {
3086 msleep(&vm_min_domains, &vm_domainset_lock, PVM, "vmwait", 0);
3088 mtx_unlock(&vm_domainset_lock);
3092 * Wait for free pages to exceed the severe threshold globally.
3095 vm_wait_severe(void)
3098 mtx_lock(&vm_domainset_lock);
3099 while (vm_page_count_severe()) {
3100 vm_severe_waiters++;
3101 msleep(&vm_severe_domains, &vm_domainset_lock, PVM,
3104 mtx_unlock(&vm_domainset_lock);
3111 return (vm_severe_waiters + vm_min_waiters + vm_pageproc_waiters);
3115 vm_wait_doms(const domainset_t *wdoms)
3119 * We use racey wakeup synchronization to avoid expensive global
3120 * locking for the pageproc when sleeping with a non-specific vm_wait.
3121 * To handle this, we only sleep for one tick in this instance. It
3122 * is expected that most allocations for the pageproc will come from
3123 * kmem or vm_page_grab* which will use the more specific and
3124 * race-free vm_wait_domain().
3126 if (curproc == pageproc) {
3127 mtx_lock(&vm_domainset_lock);
3128 vm_pageproc_waiters++;
3129 msleep(&vm_pageproc_waiters, &vm_domainset_lock, PVM | PDROP,
3133 * XXX Ideally we would wait only until the allocation could
3134 * be satisfied. This condition can cause new allocators to
3135 * consume all freed pages while old allocators wait.
3137 mtx_lock(&vm_domainset_lock);
3138 if (vm_page_count_min_set(wdoms)) {
3140 msleep(&vm_min_domains, &vm_domainset_lock,
3141 PVM | PDROP, "vmwait", 0);
3143 mtx_unlock(&vm_domainset_lock);
3150 * Sleep until free pages are available for allocation.
3151 * - Called in various places after failed memory allocations.
3154 vm_wait_domain(int domain)
3156 struct vm_domain *vmd;
3159 vmd = VM_DOMAIN(domain);
3160 vm_domain_free_assert_unlocked(vmd);
3162 if (curproc == pageproc) {
3163 mtx_lock(&vm_domainset_lock);
3164 if (vmd->vmd_free_count < vmd->vmd_pageout_free_min) {
3165 vmd->vmd_pageout_pages_needed = 1;
3166 msleep(&vmd->vmd_pageout_pages_needed,
3167 &vm_domainset_lock, PDROP | PSWP, "VMWait", 0);
3169 mtx_unlock(&vm_domainset_lock);
3171 if (pageproc == NULL)
3172 panic("vm_wait in early boot");
3173 DOMAINSET_ZERO(&wdom);
3174 DOMAINSET_SET(vmd->vmd_domain, &wdom);
3175 vm_wait_doms(&wdom);
3182 * Sleep until free pages are available for allocation in the
3183 * affinity domains of the obj. If obj is NULL, the domain set
3184 * for the calling thread is used.
3185 * Called in various places after failed memory allocations.
3188 vm_wait(vm_object_t obj)
3190 struct domainset *d;
3195 * Carefully fetch pointers only once: the struct domainset
3196 * itself is ummutable but the pointer might change.
3199 d = obj->domain.dr_policy;
3201 d = curthread->td_domain.dr_policy;
3203 vm_wait_doms(&d->ds_mask);
3207 * vm_domain_alloc_fail:
3209 * Called when a page allocation function fails. Informs the
3210 * pagedaemon and performs the requested wait. Requires the
3211 * domain_free and object lock on entry. Returns with the
3212 * object lock held and free lock released. Returns an error when
3213 * retry is necessary.
3217 vm_domain_alloc_fail(struct vm_domain *vmd, vm_object_t object, int req)
3220 vm_domain_free_assert_unlocked(vmd);
3222 atomic_add_int(&vmd->vmd_pageout_deficit,
3223 max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1));
3224 if (req & (VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL)) {
3226 VM_OBJECT_WUNLOCK(object);
3227 vm_wait_domain(vmd->vmd_domain);
3229 VM_OBJECT_WLOCK(object);
3230 if (req & VM_ALLOC_WAITOK)
3240 * Sleep until free pages are available for allocation.
3241 * - Called only in vm_fault so that processes page faulting
3242 * can be easily tracked.
3243 * - Sleeps at a lower priority than vm_wait() so that vm_wait()ing
3244 * processes will be able to grab memory first. Do not change
3245 * this balance without careful testing first.
3248 vm_waitpfault(struct domainset *dset, int timo)
3252 * XXX Ideally we would wait only until the allocation could
3253 * be satisfied. This condition can cause new allocators to
3254 * consume all freed pages while old allocators wait.
3256 mtx_lock(&vm_domainset_lock);
3257 if (vm_page_count_min_set(&dset->ds_mask)) {
3259 msleep(&vm_min_domains, &vm_domainset_lock, PUSER | PDROP,
3262 mtx_unlock(&vm_domainset_lock);
3265 static struct vm_pagequeue *
3266 vm_page_pagequeue(vm_page_t m)
3271 if ((queue = atomic_load_8(&m->a.queue)) == PQ_NONE)
3273 return (&vm_pagequeue_domain(m)->vmd_pagequeues[queue]);
3277 vm_pqbatch_process_page(struct vm_pagequeue *pq, vm_page_t m)
3279 struct vm_domain *vmd;
3282 CRITICAL_ASSERT(curthread);
3283 vm_pagequeue_assert_locked(pq);
3286 * The page daemon is allowed to set m->a.queue = PQ_NONE without
3287 * the page queue lock held. In this case it is about to free the page,
3288 * which must not have any queue state.
3290 qflags = atomic_load_16(&m->a.flags);
3291 KASSERT(pq == vm_page_pagequeue(m) ||
3292 (qflags & PGA_QUEUE_STATE_MASK) == 0,
3293 ("page %p doesn't belong to queue %p but has aflags %#x",
3296 if ((qflags & PGA_DEQUEUE) != 0) {
3297 if (__predict_true((qflags & PGA_ENQUEUED) != 0))
3298 vm_pagequeue_remove(pq, m);
3299 vm_page_dequeue_complete(m);
3300 counter_u64_add(queue_ops, 1);
3301 } else if ((qflags & (PGA_REQUEUE | PGA_REQUEUE_HEAD)) != 0) {
3302 if ((qflags & PGA_ENQUEUED) != 0)
3303 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q);
3305 vm_pagequeue_cnt_inc(pq);
3306 vm_page_aflag_set(m, PGA_ENQUEUED);
3310 * Give PGA_REQUEUE_HEAD precedence over PGA_REQUEUE.
3311 * In particular, if both flags are set in close succession,
3312 * only PGA_REQUEUE_HEAD will be applied, even if it was set
3315 if ((qflags & PGA_REQUEUE_HEAD) != 0) {
3316 KASSERT(m->a.queue == PQ_INACTIVE,
3317 ("head enqueue not supported for page %p", m));
3318 vmd = vm_pagequeue_domain(m);
3319 TAILQ_INSERT_BEFORE(&vmd->vmd_inacthead, m, plinks.q);
3321 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q);
3323 vm_page_aflag_clear(m, qflags & (PGA_REQUEUE |
3325 counter_u64_add(queue_ops, 1);
3327 counter_u64_add(queue_nops, 1);
3332 vm_pqbatch_process(struct vm_pagequeue *pq, struct vm_batchqueue *bq,
3338 for (i = 0; i < bq->bq_cnt; i++) {
3340 if (__predict_false(m->a.queue != queue))
3342 vm_pqbatch_process_page(pq, m);
3344 vm_batchqueue_init(bq);
3348 * vm_page_pqbatch_submit: [ internal use only ]
3350 * Enqueue a page in the specified page queue's batched work queue.
3351 * The caller must have encoded the requested operation in the page
3352 * structure's a.flags field.
3355 vm_page_pqbatch_submit(vm_page_t m, uint8_t queue)
3357 struct vm_batchqueue *bq;
3358 struct vm_pagequeue *pq;
3361 KASSERT((m->oflags & VPO_UNMANAGED) == 0,
3362 ("page %p is unmanaged", m));
3363 KASSERT(mtx_owned(vm_page_lockptr(m)) || m->object == NULL,
3364 ("missing synchronization for page %p", m));
3365 KASSERT(queue < PQ_COUNT, ("invalid queue %d", queue));
3367 domain = vm_phys_domain(m);
3368 pq = &vm_pagequeue_domain(m)->vmd_pagequeues[queue];
3371 bq = DPCPU_PTR(pqbatch[domain][queue]);
3372 if (vm_batchqueue_insert(bq, m)) {
3377 vm_pagequeue_lock(pq);
3379 bq = DPCPU_PTR(pqbatch[domain][queue]);
3380 vm_pqbatch_process(pq, bq, queue);
3383 * The page may have been logically dequeued before we acquired the
3384 * page queue lock. In this case, since we either hold the page lock
3385 * or the page is being freed, a different thread cannot be concurrently
3386 * enqueuing the page.
3388 if (__predict_true(m->a.queue == queue))
3389 vm_pqbatch_process_page(pq, m);
3391 KASSERT(m->a.queue == PQ_NONE,
3392 ("invalid queue transition for page %p", m));
3393 KASSERT((m->a.flags & PGA_ENQUEUED) == 0,
3394 ("page %p is enqueued with invalid queue index", m));
3396 vm_pagequeue_unlock(pq);
3401 * vm_page_pqbatch_drain: [ internal use only ]
3403 * Force all per-CPU page queue batch queues to be drained. This is
3404 * intended for use in severe memory shortages, to ensure that pages
3405 * do not remain stuck in the batch queues.
3408 vm_page_pqbatch_drain(void)
3411 struct vm_domain *vmd;
3412 struct vm_pagequeue *pq;
3413 int cpu, domain, queue;
3418 sched_bind(td, cpu);
3421 for (domain = 0; domain < vm_ndomains; domain++) {
3422 vmd = VM_DOMAIN(domain);
3423 for (queue = 0; queue < PQ_COUNT; queue++) {
3424 pq = &vmd->vmd_pagequeues[queue];
3425 vm_pagequeue_lock(pq);
3427 vm_pqbatch_process(pq,
3428 DPCPU_PTR(pqbatch[domain][queue]), queue);
3430 vm_pagequeue_unlock(pq);
3440 * Complete the logical removal of a page from a page queue. We must be
3441 * careful to synchronize with the page daemon, which may be concurrently
3442 * examining the page with only the page lock held. The page must not be
3443 * in a state where it appears to be logically enqueued.
3446 vm_page_dequeue_complete(vm_page_t m)
3449 m->a.queue = PQ_NONE;
3450 atomic_thread_fence_rel();
3451 vm_page_aflag_clear(m, PGA_QUEUE_STATE_MASK);
3455 * vm_page_dequeue_deferred: [ internal use only ]
3457 * Request removal of the given page from its current page
3458 * queue. Physical removal from the queue may be deferred
3461 * The page must be locked.
3464 vm_page_dequeue_deferred(vm_page_t m)
3468 vm_page_assert_locked(m);
3470 if ((queue = vm_page_queue(m)) == PQ_NONE)
3474 * Set PGA_DEQUEUE if it is not already set to handle a concurrent call
3475 * to vm_page_dequeue_deferred_free(). In particular, avoid modifying
3476 * the page's queue state once vm_page_dequeue_deferred_free() has been
3477 * called. In the event of a race, two batch queue entries for the page
3478 * will be created, but the second will have no effect.
3480 if (vm_page_pqstate_cmpset(m, queue, queue, PGA_DEQUEUE, PGA_DEQUEUE))
3481 vm_page_pqbatch_submit(m, queue);
3485 * A variant of vm_page_dequeue_deferred() that does not assert the page
3486 * lock and is only to be called from vm_page_free_prep(). Because the
3487 * page is being freed, we can assume that nothing other than the page
3488 * daemon is scheduling queue operations on this page, so we get for
3489 * free the mutual exclusion that is otherwise provided by the page lock.
3490 * To handle races, the page daemon must take care to atomically check
3491 * for PGA_DEQUEUE when updating queue state.
3494 vm_page_dequeue_deferred_free(vm_page_t m)
3498 KASSERT(m->ref_count == 0, ("page %p has references", m));
3501 if ((m->a.flags & PGA_DEQUEUE) != 0)
3503 atomic_thread_fence_acq();
3504 if ((queue = atomic_load_8(&m->a.queue)) == PQ_NONE)
3506 if (vm_page_pqstate_cmpset(m, queue, queue, PGA_DEQUEUE,
3508 vm_page_pqbatch_submit(m, queue);
3517 * Remove the page from whichever page queue it's in, if any.
3518 * The page must either be locked or unallocated. This constraint
3519 * ensures that the queue state of the page will remain consistent
3520 * after this function returns.
3523 vm_page_dequeue(vm_page_t m)
3525 struct vm_pagequeue *pq, *pq1;
3528 KASSERT(mtx_owned(vm_page_lockptr(m)) || m->ref_count == 0,
3529 ("page %p is allocated and unlocked", m));
3531 for (pq = vm_page_pagequeue(m);; pq = pq1) {
3534 * A thread may be concurrently executing
3535 * vm_page_dequeue_complete(). Ensure that all queue
3536 * state is cleared before we return.
3538 aflags = atomic_load_16(&m->a.flags);
3539 if ((aflags & PGA_QUEUE_STATE_MASK) == 0)
3541 KASSERT((aflags & PGA_DEQUEUE) != 0,
3542 ("page %p has unexpected queue state flags %#x",
3546 * Busy wait until the thread updating queue state is
3547 * finished. Such a thread must be executing in a
3551 pq1 = vm_page_pagequeue(m);
3554 vm_pagequeue_lock(pq);
3555 if ((pq1 = vm_page_pagequeue(m)) == pq)
3557 vm_pagequeue_unlock(pq);
3559 KASSERT(pq == vm_page_pagequeue(m),
3560 ("%s: page %p migrated directly between queues", __func__, m));
3561 KASSERT((m->a.flags & PGA_DEQUEUE) != 0 ||
3562 mtx_owned(vm_page_lockptr(m)),
3563 ("%s: queued unlocked page %p", __func__, m));
3565 if ((m->a.flags & PGA_ENQUEUED) != 0)
3566 vm_pagequeue_remove(pq, m);
3567 vm_page_dequeue_complete(m);
3568 vm_pagequeue_unlock(pq);
3572 * Schedule the given page for insertion into the specified page queue.
3573 * Physical insertion of the page may be deferred indefinitely.
3576 vm_page_enqueue(vm_page_t m, uint8_t queue)
3579 vm_page_assert_locked(m);
3580 KASSERT(m->a.queue == PQ_NONE &&
3581 (m->a.flags & PGA_QUEUE_STATE_MASK) == 0,
3582 ("%s: page %p is already enqueued", __func__, m));
3583 KASSERT(m->ref_count > 0,
3584 ("%s: page %p does not carry any references", __func__, m));
3587 if ((m->a.flags & PGA_REQUEUE) == 0)
3588 vm_page_aflag_set(m, PGA_REQUEUE);
3589 vm_page_pqbatch_submit(m, queue);
3593 * vm_page_requeue: [ internal use only ]
3595 * Schedule a requeue of the given page.
3597 * The page must be locked.
3600 vm_page_requeue(vm_page_t m)
3603 vm_page_assert_locked(m);
3604 KASSERT(vm_page_queue(m) != PQ_NONE,
3605 ("%s: page %p is not logically enqueued", __func__, m));
3606 KASSERT(m->ref_count > 0,
3607 ("%s: page %p does not carry any references", __func__, m));
3609 if ((m->a.flags & PGA_REQUEUE) == 0)
3610 vm_page_aflag_set(m, PGA_REQUEUE);
3611 vm_page_pqbatch_submit(m, atomic_load_8(&m->a.queue));
3615 * vm_page_swapqueue: [ internal use only ]
3617 * Move the page from one queue to another, or to the tail of its
3618 * current queue, in the face of a possible concurrent call to
3619 * vm_page_dequeue_deferred_free().
3622 vm_page_swapqueue(vm_page_t m, uint8_t oldq, uint8_t newq)
3624 struct vm_pagequeue *pq;
3628 KASSERT(oldq < PQ_COUNT && newq < PQ_COUNT && oldq != newq,
3629 ("vm_page_swapqueue: invalid queues (%d, %d)", oldq, newq));
3630 vm_page_assert_locked(m);
3632 pq = &vm_pagequeue_domain(m)->vmd_pagequeues[oldq];
3633 vm_pagequeue_lock(pq);
3636 * The physical queue state might change at any point before the page
3637 * queue lock is acquired, so we must verify that we hold the correct
3638 * lock before proceeding.
3640 if (__predict_false(m->a.queue != oldq)) {
3641 vm_pagequeue_unlock(pq);
3646 * Once the queue index of the page changes, there is nothing
3647 * synchronizing with further updates to the physical queue state.
3648 * Therefore we must remove the page from the queue now in anticipation
3649 * of a successful commit, and be prepared to roll back.
3651 if (__predict_true((m->a.flags & PGA_ENQUEUED) != 0)) {
3652 next = TAILQ_NEXT(m, plinks.q);
3653 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q);
3654 vm_page_aflag_clear(m, PGA_ENQUEUED);
3661 * Atomically update the queue field and set PGA_REQUEUE while
3662 * ensuring that PGA_DEQUEUE has not been set.
3664 if (__predict_false(!vm_page_pqstate_cmpset(m, oldq, newq, PGA_DEQUEUE,
3667 vm_page_aflag_set(m, PGA_ENQUEUED);
3669 TAILQ_INSERT_BEFORE(next, m, plinks.q);
3671 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q);
3673 vm_pagequeue_unlock(pq);
3676 vm_pagequeue_cnt_dec(pq);
3677 vm_pagequeue_unlock(pq);
3678 vm_page_pqbatch_submit(m, newq);
3682 * vm_page_free_prep:
3684 * Prepares the given page to be put on the free list,
3685 * disassociating it from any VM object. The caller may return
3686 * the page to the free list only if this function returns true.
3688 * The object must be locked. The page must be locked if it is
3692 vm_page_free_prep(vm_page_t m)
3696 * Synchronize with threads that have dropped a reference to this
3699 atomic_thread_fence_acq();
3701 if (vm_page_sbusied(m))
3702 panic("vm_page_free_prep: freeing shared busy page %p", m);
3704 #if defined(DIAGNOSTIC) && defined(PHYS_TO_DMAP)
3705 if (PMAP_HAS_DMAP && (m->flags & PG_ZERO) != 0) {
3708 p = (uint64_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m));
3709 for (i = 0; i < PAGE_SIZE / sizeof(uint64_t); i++, p++)
3710 KASSERT(*p == 0, ("vm_page_free_prep %p PG_ZERO %d %jx",
3711 m, i, (uintmax_t)*p));
3714 if ((m->oflags & VPO_UNMANAGED) == 0) {
3715 KASSERT(!pmap_page_is_mapped(m),
3716 ("vm_page_free_prep: freeing mapped page %p", m));
3717 KASSERT((m->a.flags & (PGA_EXECUTABLE | PGA_WRITEABLE)) == 0,
3718 ("vm_page_free_prep: mapping flags set in page %p", m));
3720 KASSERT(m->a.queue == PQ_NONE,
3721 ("vm_page_free_prep: unmanaged page %p is queued", m));
3723 VM_CNT_INC(v_tfree);
3725 if (m->object != NULL) {
3726 KASSERT(((m->oflags & VPO_UNMANAGED) != 0) ==
3727 ((m->object->flags & OBJ_UNMANAGED) != 0),
3728 ("vm_page_free_prep: managed flag mismatch for page %p",
3730 vm_page_object_remove(m);
3733 * The object reference can be released without an atomic
3736 KASSERT((m->flags & PG_FICTITIOUS) != 0 ||
3737 m->ref_count == VPRC_OBJREF,
3738 ("vm_page_free_prep: page %p has unexpected ref_count %u",
3741 m->ref_count -= VPRC_OBJREF;
3745 if (vm_page_xbusied(m))
3746 panic("vm_page_free_prep: freeing exclusive busy page %p", m);
3749 * If fictitious remove object association and
3752 if ((m->flags & PG_FICTITIOUS) != 0) {
3753 KASSERT(m->ref_count == 1,
3754 ("fictitious page %p is referenced", m));
3755 KASSERT(m->a.queue == PQ_NONE,
3756 ("fictitious page %p is queued", m));
3761 * Pages need not be dequeued before they are returned to the physical
3762 * memory allocator, but they must at least be marked for a deferred
3765 if ((m->oflags & VPO_UNMANAGED) == 0)
3766 vm_page_dequeue_deferred_free(m);
3771 if (m->ref_count != 0)
3772 panic("vm_page_free_prep: page %p has references", m);
3775 * Restore the default memory attribute to the page.
3777 if (pmap_page_get_memattr(m) != VM_MEMATTR_DEFAULT)
3778 pmap_page_set_memattr(m, VM_MEMATTR_DEFAULT);
3780 #if VM_NRESERVLEVEL > 0
3782 * Determine whether the page belongs to a reservation. If the page was
3783 * allocated from a per-CPU cache, it cannot belong to a reservation, so
3784 * as an optimization, we avoid the check in that case.
3786 if ((m->flags & PG_PCPU_CACHE) == 0 && vm_reserv_free_page(m))
3796 * Returns the given page to the free list, disassociating it
3797 * from any VM object.
3799 * The object must be locked. The page must be locked if it is
3803 vm_page_free_toq(vm_page_t m)
3805 struct vm_domain *vmd;
3808 if (!vm_page_free_prep(m))
3811 vmd = vm_pagequeue_domain(m);
3812 zone = vmd->vmd_pgcache[m->pool].zone;
3813 if ((m->flags & PG_PCPU_CACHE) != 0 && zone != NULL) {
3817 vm_domain_free_lock(vmd);
3818 vm_phys_free_pages(m, 0);
3819 vm_domain_free_unlock(vmd);
3820 vm_domain_freecnt_inc(vmd, 1);
3824 * vm_page_free_pages_toq:
3826 * Returns a list of pages to the free list, disassociating it
3827 * from any VM object. In other words, this is equivalent to
3828 * calling vm_page_free_toq() for each page of a list of VM objects.
3830 * The objects must be locked. The pages must be locked if it is
3834 vm_page_free_pages_toq(struct spglist *free, bool update_wire_count)
3839 if (SLIST_EMPTY(free))
3843 while ((m = SLIST_FIRST(free)) != NULL) {
3845 SLIST_REMOVE_HEAD(free, plinks.s.ss);
3846 vm_page_free_toq(m);
3849 if (update_wire_count)
3854 * Mark this page as wired down, preventing reclamation by the page daemon
3855 * or when the containing object is destroyed.
3858 vm_page_wire(vm_page_t m)
3862 KASSERT(m->object != NULL,
3863 ("vm_page_wire: page %p does not belong to an object", m));
3864 if (!vm_page_busied(m) && !vm_object_busied(m->object))
3865 VM_OBJECT_ASSERT_LOCKED(m->object);
3866 KASSERT((m->flags & PG_FICTITIOUS) == 0 ||
3867 VPRC_WIRE_COUNT(m->ref_count) >= 1,
3868 ("vm_page_wire: fictitious page %p has zero wirings", m));
3870 old = atomic_fetchadd_int(&m->ref_count, 1);
3871 KASSERT(VPRC_WIRE_COUNT(old) != VPRC_WIRE_COUNT_MAX,
3872 ("vm_page_wire: counter overflow for page %p", m));
3873 if (VPRC_WIRE_COUNT(old) == 0)
3878 * Attempt to wire a mapped page following a pmap lookup of that page.
3879 * This may fail if a thread is concurrently tearing down mappings of the page.
3880 * The transient failure is acceptable because it translates to the
3881 * failure of the caller pmap_extract_and_hold(), which should be then
3882 * followed by the vm_fault() fallback, see e.g. vm_fault_quick_hold_pages().
3885 vm_page_wire_mapped(vm_page_t m)
3892 ("vm_page_wire_mapped: wiring unreferenced page %p", m));
3893 if ((old & VPRC_BLOCKED) != 0)
3895 } while (!atomic_fcmpset_int(&m->ref_count, &old, old + 1));
3897 if (VPRC_WIRE_COUNT(old) == 0)
3903 * Release one wiring of the specified page, potentially allowing it to be
3906 * Only managed pages belonging to an object can be paged out. If the number
3907 * of wirings transitions to zero and the page is eligible for page out, then
3908 * the page is added to the specified paging queue. If the released wiring
3909 * represented the last reference to the page, the page is freed.
3911 * A managed page must be locked.
3914 vm_page_unwire(vm_page_t m, uint8_t queue)
3919 KASSERT(queue < PQ_COUNT,
3920 ("vm_page_unwire: invalid queue %u request for page %p", queue, m));
3922 if ((m->oflags & VPO_UNMANAGED) != 0) {
3923 if (vm_page_unwire_noq(m) && m->ref_count == 0)
3929 * Update LRU state before releasing the wiring reference.
3930 * We only need to do this once since we hold the page lock.
3931 * Use a release store when updating the reference count to
3932 * synchronize with vm_page_free_prep().
3937 KASSERT(VPRC_WIRE_COUNT(old) > 0,
3938 ("vm_page_unwire: wire count underflow for page %p", m));
3939 if (!locked && VPRC_WIRE_COUNT(old) == 1) {
3942 if (queue == PQ_ACTIVE && vm_page_queue(m) == PQ_ACTIVE)
3943 vm_page_reference(m);
3945 vm_page_mvqueue(m, queue);
3947 } while (!atomic_fcmpset_rel_int(&m->ref_count, &old, old - 1));
3950 * Release the lock only after the wiring is released, to ensure that
3951 * the page daemon does not encounter and dequeue the page while it is
3957 if (VPRC_WIRE_COUNT(old) == 1) {
3965 * Unwire a page without (re-)inserting it into a page queue. It is up
3966 * to the caller to enqueue, requeue, or free the page as appropriate.
3967 * In most cases involving managed pages, vm_page_unwire() should be used
3971 vm_page_unwire_noq(vm_page_t m)
3975 old = vm_page_drop(m, 1);
3976 KASSERT(VPRC_WIRE_COUNT(old) != 0,
3977 ("vm_page_unref: counter underflow for page %p", m));
3978 KASSERT((m->flags & PG_FICTITIOUS) == 0 || VPRC_WIRE_COUNT(old) > 1,
3979 ("vm_page_unref: missing ref on fictitious page %p", m));
3981 if (VPRC_WIRE_COUNT(old) > 1)
3988 * Ensure that the page is in the specified page queue. If the page is
3989 * active or being moved to the active queue, ensure that its act_count is
3990 * at least ACT_INIT but do not otherwise mess with it. Otherwise, ensure that
3991 * the page is at the tail of its page queue.
3993 * The page may be wired. The caller should release its wiring reference
3994 * before releasing the page lock, otherwise the page daemon may immediately
3997 * A managed page must be locked.
3999 static __always_inline void
4000 vm_page_mvqueue(vm_page_t m, const uint8_t nqueue)
4003 vm_page_assert_locked(m);
4004 KASSERT((m->oflags & VPO_UNMANAGED) == 0,
4005 ("vm_page_mvqueue: page %p is unmanaged", m));
4006 KASSERT(m->ref_count > 0,
4007 ("%s: page %p does not carry any references", __func__, m));
4009 if (vm_page_queue(m) != nqueue) {
4011 vm_page_enqueue(m, nqueue);
4012 } else if (nqueue != PQ_ACTIVE) {
4016 if (nqueue == PQ_ACTIVE && m->a.act_count < ACT_INIT)
4017 m->a.act_count = ACT_INIT;
4021 * Put the specified page on the active list (if appropriate).
4024 vm_page_activate(vm_page_t m)
4027 if ((m->oflags & VPO_UNMANAGED) != 0 || vm_page_wired(m))
4029 vm_page_mvqueue(m, PQ_ACTIVE);
4033 * Move the specified page to the tail of the inactive queue, or requeue
4034 * the page if it is already in the inactive queue.
4037 vm_page_deactivate(vm_page_t m)
4040 if ((m->oflags & VPO_UNMANAGED) != 0 || vm_page_wired(m))
4042 vm_page_mvqueue(m, PQ_INACTIVE);
4046 * Move the specified page close to the head of the inactive queue,
4047 * bypassing LRU. A marker page is used to maintain FIFO ordering.
4048 * As with regular enqueues, we use a per-CPU batch queue to reduce
4049 * contention on the page queue lock.
4052 _vm_page_deactivate_noreuse(vm_page_t m)
4055 vm_page_assert_locked(m);
4057 if (!vm_page_inactive(m)) {
4059 m->a.queue = PQ_INACTIVE;
4061 if ((m->a.flags & PGA_REQUEUE_HEAD) == 0)
4062 vm_page_aflag_set(m, PGA_REQUEUE_HEAD);
4063 vm_page_pqbatch_submit(m, PQ_INACTIVE);
4067 vm_page_deactivate_noreuse(vm_page_t m)
4070 KASSERT(m->object != NULL,
4071 ("vm_page_deactivate_noreuse: page %p has no object", m));
4073 if ((m->oflags & VPO_UNMANAGED) == 0 && !vm_page_wired(m))
4074 _vm_page_deactivate_noreuse(m);
4078 * Put a page in the laundry, or requeue it if it is already there.
4081 vm_page_launder(vm_page_t m)
4084 if ((m->oflags & VPO_UNMANAGED) != 0 || vm_page_wired(m))
4086 vm_page_mvqueue(m, PQ_LAUNDRY);
4090 * Put a page in the PQ_UNSWAPPABLE holding queue.
4093 vm_page_unswappable(vm_page_t m)
4096 vm_page_assert_locked(m);
4097 KASSERT(!vm_page_wired(m) && (m->oflags & VPO_UNMANAGED) == 0,
4098 ("page %p already unswappable", m));
4101 vm_page_enqueue(m, PQ_UNSWAPPABLE);
4105 vm_page_release_toq(vm_page_t m, int flags)
4108 vm_page_assert_locked(m);
4111 * Use a check of the valid bits to determine whether we should
4112 * accelerate reclamation of the page. The object lock might not be
4113 * held here, in which case the check is racy. At worst we will either
4114 * accelerate reclamation of a valid page and violate LRU, or
4115 * unnecessarily defer reclamation of an invalid page.
4117 * If we were asked to not cache the page, place it near the head of the
4118 * inactive queue so that is reclaimed sooner.
4120 if ((flags & (VPR_TRYFREE | VPR_NOREUSE)) != 0 || m->valid == 0)
4121 _vm_page_deactivate_noreuse(m);
4122 else if (vm_page_active(m))
4123 vm_page_reference(m);
4125 vm_page_mvqueue(m, PQ_INACTIVE);
4129 * Unwire a page and either attempt to free it or re-add it to the page queues.
4132 vm_page_release(vm_page_t m, int flags)
4138 KASSERT((m->oflags & VPO_UNMANAGED) == 0,
4139 ("vm_page_release: page %p is unmanaged", m));
4141 if ((flags & VPR_TRYFREE) != 0) {
4143 object = (vm_object_t)atomic_load_ptr(&m->object);
4146 /* Depends on type-stability. */
4147 if (vm_page_busied(m) || !VM_OBJECT_TRYWLOCK(object))
4149 if (object == m->object) {
4150 vm_page_release_locked(m, flags);
4151 VM_OBJECT_WUNLOCK(object);
4154 VM_OBJECT_WUNLOCK(object);
4159 * Update LRU state before releasing the wiring reference.
4160 * Use a release store when updating the reference count to
4161 * synchronize with vm_page_free_prep().
4166 KASSERT(VPRC_WIRE_COUNT(old) > 0,
4167 ("vm_page_unwire: wire count underflow for page %p", m));
4168 if (!locked && VPRC_WIRE_COUNT(old) == 1) {
4171 vm_page_release_toq(m, flags);
4173 } while (!atomic_fcmpset_rel_int(&m->ref_count, &old, old - 1));
4176 * Release the lock only after the wiring is released, to ensure that
4177 * the page daemon does not encounter and dequeue the page while it is
4183 if (VPRC_WIRE_COUNT(old) == 1) {
4190 /* See vm_page_release(). */
4192 vm_page_release_locked(vm_page_t m, int flags)
4195 VM_OBJECT_ASSERT_WLOCKED(m->object);
4196 KASSERT((m->oflags & VPO_UNMANAGED) == 0,
4197 ("vm_page_release_locked: page %p is unmanaged", m));
4199 if (vm_page_unwire_noq(m)) {
4200 if ((flags & VPR_TRYFREE) != 0 &&
4201 (m->object->ref_count == 0 || !pmap_page_is_mapped(m)) &&
4202 m->dirty == 0 && vm_page_tryxbusy(m)) {
4206 vm_page_release_toq(m, flags);
4213 vm_page_try_blocked_op(vm_page_t m, void (*op)(vm_page_t))
4217 KASSERT(m->object != NULL && (m->oflags & VPO_UNMANAGED) == 0,
4218 ("vm_page_try_blocked_op: page %p has no object", m));
4219 KASSERT(vm_page_busied(m),
4220 ("vm_page_try_blocked_op: page %p is not busy", m));
4221 VM_OBJECT_ASSERT_LOCKED(m->object);
4226 ("vm_page_try_blocked_op: page %p has no references", m));
4227 if (VPRC_WIRE_COUNT(old) != 0)
4229 } while (!atomic_fcmpset_int(&m->ref_count, &old, old | VPRC_BLOCKED));
4234 * If the object is read-locked, new wirings may be created via an
4237 old = vm_page_drop(m, VPRC_BLOCKED);
4238 KASSERT(!VM_OBJECT_WOWNED(m->object) ||
4239 old == (VPRC_BLOCKED | VPRC_OBJREF),
4240 ("vm_page_try_blocked_op: unexpected refcount value %u for %p",
4246 * Atomically check for wirings and remove all mappings of the page.
4249 vm_page_try_remove_all(vm_page_t m)
4252 return (vm_page_try_blocked_op(m, pmap_remove_all));
4256 * Atomically check for wirings and remove all writeable mappings of the page.
4259 vm_page_try_remove_write(vm_page_t m)
4262 return (vm_page_try_blocked_op(m, pmap_remove_write));
4268 * Apply the specified advice to the given page.
4270 * The object and page must be locked.
4273 vm_page_advise(vm_page_t m, int advice)
4276 vm_page_assert_locked(m);
4277 VM_OBJECT_ASSERT_WLOCKED(m->object);
4278 if (advice == MADV_FREE)
4280 * Mark the page clean. This will allow the page to be freed
4281 * without first paging it out. MADV_FREE pages are often
4282 * quickly reused by malloc(3), so we do not do anything that
4283 * would result in a page fault on a later access.
4286 else if (advice != MADV_DONTNEED) {
4287 if (advice == MADV_WILLNEED)
4288 vm_page_activate(m);
4293 * Clear any references to the page. Otherwise, the page daemon will
4294 * immediately reactivate the page.
4296 vm_page_aflag_clear(m, PGA_REFERENCED);
4298 if (advice != MADV_FREE && m->dirty == 0 && pmap_is_modified(m))
4302 * Place clean pages near the head of the inactive queue rather than
4303 * the tail, thus defeating the queue's LRU operation and ensuring that
4304 * the page will be reused quickly. Dirty pages not already in the
4305 * laundry are moved there.
4308 vm_page_deactivate_noreuse(m);
4309 else if (!vm_page_in_laundry(m))
4314 vm_page_grab_pflags(int allocflags)
4318 KASSERT((allocflags & VM_ALLOC_NOBUSY) == 0 ||
4319 (allocflags & VM_ALLOC_WIRED) != 0,
4320 ("vm_page_grab_pflags: the pages must be busied or wired"));
4321 KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 ||
4322 (allocflags & VM_ALLOC_IGN_SBUSY) != 0,
4323 ("vm_page_grab_pflags: VM_ALLOC_SBUSY/VM_ALLOC_IGN_SBUSY "
4325 pflags = allocflags &
4326 ~(VM_ALLOC_NOWAIT | VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL |
4328 if ((allocflags & VM_ALLOC_NOWAIT) == 0)
4329 pflags |= VM_ALLOC_WAITFAIL;
4330 if ((allocflags & VM_ALLOC_IGN_SBUSY) != 0)
4331 pflags |= VM_ALLOC_SBUSY;
4337 * Grab a page, waiting until we are waken up due to the page
4338 * changing state. We keep on waiting, if the page continues
4339 * to be in the object. If the page doesn't exist, first allocate it
4340 * and then conditionally zero it.
4342 * This routine may sleep.
4344 * The object must be locked on entry. The lock will, however, be released
4345 * and reacquired if the routine sleeps.
4348 vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags)
4353 VM_OBJECT_ASSERT_WLOCKED(object);
4354 pflags = vm_page_grab_pflags(allocflags);
4356 if ((m = vm_page_lookup(object, pindex)) != NULL) {
4357 if (!vm_page_acquire_flags(m, allocflags)) {
4358 if (vm_page_busy_sleep_flags(object, m, "pgrbwt",
4365 if ((allocflags & VM_ALLOC_NOCREAT) != 0)
4367 m = vm_page_alloc(object, pindex, pflags);
4369 if ((allocflags & VM_ALLOC_NOWAIT) != 0)
4373 if (allocflags & VM_ALLOC_ZERO && (m->flags & PG_ZERO) == 0)
4377 if ((allocflags & VM_ALLOC_NOBUSY) != 0) {
4378 if ((allocflags & VM_ALLOC_IGN_SBUSY) != 0)
4387 * Grab a page and make it valid, paging in if necessary. Pages missing from
4388 * their pager are zero filled and validated. If a VM_ALLOC_COUNT is supplied
4389 * and the page is not valid as many as VM_INITIAL_PAGEIN pages can be brought
4390 * in simultaneously. Additional pages will be left on a paging queue but
4391 * will neither be wired nor busy regardless of allocflags.
4394 vm_page_grab_valid(vm_page_t *mp, vm_object_t object, vm_pindex_t pindex, int allocflags)
4397 vm_page_t ma[VM_INITIAL_PAGEIN];
4399 int after, i, pflags, rv;
4401 KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 ||
4402 (allocflags & VM_ALLOC_IGN_SBUSY) != 0,
4403 ("vm_page_grab_valid: VM_ALLOC_SBUSY/VM_ALLOC_IGN_SBUSY mismatch"));
4404 KASSERT((allocflags &
4405 (VM_ALLOC_NOWAIT | VM_ALLOC_WAITFAIL | VM_ALLOC_ZERO)) == 0,
4406 ("vm_page_grab_valid: Invalid flags 0x%X", allocflags));
4407 VM_OBJECT_ASSERT_WLOCKED(object);
4408 pflags = allocflags & ~(VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY);
4409 pflags |= VM_ALLOC_WAITFAIL;
4413 if ((m = vm_page_lookup(object, pindex)) != NULL) {
4415 * If the page is fully valid it can only become invalid
4416 * with the object lock held. If it is not valid it can
4417 * become valid with the busy lock held. Therefore, we
4418 * may unnecessarily lock the exclusive busy here if we
4419 * race with I/O completion not using the object lock.
4420 * However, we will not end up with an invalid page and a
4423 if (!vm_page_all_valid(m) ||
4424 (allocflags & (VM_ALLOC_IGN_SBUSY | VM_ALLOC_SBUSY)) == 0) {
4425 sleep = !vm_page_tryxbusy(m);
4428 sleep = !vm_page_trysbusy(m);
4430 (void)vm_page_busy_sleep_flags(object, m, "pgrbwt",
4434 if ((allocflags & VM_ALLOC_NOCREAT) != 0 &&
4435 !vm_page_all_valid(m)) {
4441 return (VM_PAGER_FAIL);
4443 if ((allocflags & VM_ALLOC_WIRED) != 0)
4445 if (vm_page_all_valid(m))
4447 } else if ((allocflags & VM_ALLOC_NOCREAT) != 0) {
4449 return (VM_PAGER_FAIL);
4450 } else if ((m = vm_page_alloc(object, pindex, pflags)) != NULL) {
4456 vm_page_assert_xbusied(m);
4458 if (vm_pager_has_page(object, pindex, NULL, &after)) {
4459 after = MIN(after, VM_INITIAL_PAGEIN);
4460 after = MIN(after, allocflags >> VM_ALLOC_COUNT_SHIFT);
4461 after = MAX(after, 1);
4463 for (i = 1; i < after; i++) {
4464 if ((ma[i] = vm_page_next(ma[i - 1])) != NULL) {
4465 if (ma[i]->valid || !vm_page_tryxbusy(ma[i]))
4468 ma[i] = vm_page_alloc(object, m->pindex + i,
4475 rv = vm_pager_get_pages(object, ma, after, NULL, NULL);
4476 /* Pager may have replaced a page. */
4478 if (rv != VM_PAGER_OK) {
4479 if ((allocflags & VM_ALLOC_WIRED) != 0)
4480 vm_page_unwire_noq(m);
4481 for (i = 0; i < after; i++) {
4482 if (!vm_page_wired(ma[i]))
4483 vm_page_free(ma[i]);
4485 vm_page_xunbusy(ma[i]);
4490 for (i = 1; i < after; i++)
4491 vm_page_readahead_finish(ma[i]);
4492 MPASS(vm_page_all_valid(m));
4494 vm_page_zero_invalid(m, TRUE);
4497 if ((allocflags & VM_ALLOC_NOBUSY) != 0) {
4503 if ((allocflags & VM_ALLOC_SBUSY) != 0 && xbusy)
4504 vm_page_busy_downgrade(m);
4506 return (VM_PAGER_OK);
4510 * Return the specified range of pages from the given object. For each
4511 * page offset within the range, if a page already exists within the object
4512 * at that offset and it is busy, then wait for it to change state. If,
4513 * instead, the page doesn't exist, then allocate it.
4515 * The caller must always specify an allocation class.
4517 * allocation classes:
4518 * VM_ALLOC_NORMAL normal process request
4519 * VM_ALLOC_SYSTEM system *really* needs the pages
4521 * The caller must always specify that the pages are to be busied and/or
4524 * optional allocation flags:
4525 * VM_ALLOC_IGN_SBUSY do not sleep on soft busy pages
4526 * VM_ALLOC_NOBUSY do not exclusive busy the page
4527 * VM_ALLOC_NOWAIT do not sleep
4528 * VM_ALLOC_SBUSY set page to sbusy state
4529 * VM_ALLOC_WIRED wire the pages
4530 * VM_ALLOC_ZERO zero and validate any invalid pages
4532 * If VM_ALLOC_NOWAIT is not specified, this routine may sleep. Otherwise, it
4533 * may return a partial prefix of the requested range.
4536 vm_page_grab_pages(vm_object_t object, vm_pindex_t pindex, int allocflags,
4537 vm_page_t *ma, int count)
4543 VM_OBJECT_ASSERT_WLOCKED(object);
4544 KASSERT(((u_int)allocflags >> VM_ALLOC_COUNT_SHIFT) == 0,
4545 ("vm_page_grap_pages: VM_ALLOC_COUNT() is not allowed"));
4547 pflags = vm_page_grab_pflags(allocflags);
4553 m = vm_radix_lookup_le(&object->rtree, pindex + i);
4554 if (m == NULL || m->pindex != pindex + i) {
4558 mpred = TAILQ_PREV(m, pglist, listq);
4559 for (; i < count; i++) {
4561 if (!vm_page_acquire_flags(m, allocflags)) {
4562 if (vm_page_busy_sleep_flags(object, m,
4563 "grbmaw", allocflags))
4568 if ((allocflags & VM_ALLOC_NOCREAT) != 0)
4570 m = vm_page_alloc_after(object, pindex + i,
4571 pflags | VM_ALLOC_COUNT(count - i), mpred);
4573 if ((allocflags & VM_ALLOC_NOWAIT) != 0)
4578 if (vm_page_none_valid(m) &&
4579 (allocflags & VM_ALLOC_ZERO) != 0) {
4580 if ((m->flags & PG_ZERO) == 0)
4584 if ((allocflags & VM_ALLOC_NOBUSY) != 0) {
4585 if ((allocflags & VM_ALLOC_IGN_SBUSY) != 0)
4591 m = vm_page_next(m);
4597 * Mapping function for valid or dirty bits in a page.
4599 * Inputs are required to range within a page.
4602 vm_page_bits(int base, int size)
4608 base + size <= PAGE_SIZE,
4609 ("vm_page_bits: illegal base/size %d/%d", base, size)
4612 if (size == 0) /* handle degenerate case */
4615 first_bit = base >> DEV_BSHIFT;
4616 last_bit = (base + size - 1) >> DEV_BSHIFT;
4618 return (((vm_page_bits_t)2 << last_bit) -
4619 ((vm_page_bits_t)1 << first_bit));
4623 vm_page_bits_set(vm_page_t m, vm_page_bits_t *bits, vm_page_bits_t set)
4626 #if PAGE_SIZE == 32768
4627 atomic_set_64((uint64_t *)bits, set);
4628 #elif PAGE_SIZE == 16384
4629 atomic_set_32((uint32_t *)bits, set);
4630 #elif (PAGE_SIZE == 8192) && defined(atomic_set_16)
4631 atomic_set_16((uint16_t *)bits, set);
4632 #elif (PAGE_SIZE == 4096) && defined(atomic_set_8)
4633 atomic_set_8((uint8_t *)bits, set);
4634 #else /* PAGE_SIZE <= 8192 */
4638 addr = (uintptr_t)bits;
4640 * Use a trick to perform a 32-bit atomic on the
4641 * containing aligned word, to not depend on the existence
4642 * of atomic_{set, clear}_{8, 16}.
4644 shift = addr & (sizeof(uint32_t) - 1);
4645 #if BYTE_ORDER == BIG_ENDIAN
4646 shift = (sizeof(uint32_t) - sizeof(vm_page_bits_t) - shift) * NBBY;
4650 addr &= ~(sizeof(uint32_t) - 1);
4651 atomic_set_32((uint32_t *)addr, set << shift);
4652 #endif /* PAGE_SIZE */
4656 vm_page_bits_clear(vm_page_t m, vm_page_bits_t *bits, vm_page_bits_t clear)
4659 #if PAGE_SIZE == 32768
4660 atomic_clear_64((uint64_t *)bits, clear);
4661 #elif PAGE_SIZE == 16384
4662 atomic_clear_32((uint32_t *)bits, clear);
4663 #elif (PAGE_SIZE == 8192) && defined(atomic_clear_16)
4664 atomic_clear_16((uint16_t *)bits, clear);
4665 #elif (PAGE_SIZE == 4096) && defined(atomic_clear_8)
4666 atomic_clear_8((uint8_t *)bits, clear);
4667 #else /* PAGE_SIZE <= 8192 */
4671 addr = (uintptr_t)bits;
4673 * Use a trick to perform a 32-bit atomic on the
4674 * containing aligned word, to not depend on the existence
4675 * of atomic_{set, clear}_{8, 16}.
4677 shift = addr & (sizeof(uint32_t) - 1);
4678 #if BYTE_ORDER == BIG_ENDIAN
4679 shift = (sizeof(uint32_t) - sizeof(vm_page_bits_t) - shift) * NBBY;
4683 addr &= ~(sizeof(uint32_t) - 1);
4684 atomic_clear_32((uint32_t *)addr, clear << shift);
4685 #endif /* PAGE_SIZE */
4688 static inline vm_page_bits_t
4689 vm_page_bits_swap(vm_page_t m, vm_page_bits_t *bits, vm_page_bits_t newbits)
4691 #if PAGE_SIZE == 32768
4695 while (atomic_fcmpset_64(bits, &old, newbits) == 0);
4697 #elif PAGE_SIZE == 16384
4701 while (atomic_fcmpset_32(bits, &old, newbits) == 0);
4703 #elif (PAGE_SIZE == 8192) && defined(atomic_fcmpset_16)
4707 while (atomic_fcmpset_16(bits, &old, newbits) == 0);
4709 #elif (PAGE_SIZE == 4096) && defined(atomic_fcmpset_8)
4713 while (atomic_fcmpset_8(bits, &old, newbits) == 0);
4715 #else /* PAGE_SIZE <= 4096*/
4717 uint32_t old, new, mask;
4720 addr = (uintptr_t)bits;
4722 * Use a trick to perform a 32-bit atomic on the
4723 * containing aligned word, to not depend on the existence
4724 * of atomic_{set, swap, clear}_{8, 16}.
4726 shift = addr & (sizeof(uint32_t) - 1);
4727 #if BYTE_ORDER == BIG_ENDIAN
4728 shift = (sizeof(uint32_t) - sizeof(vm_page_bits_t) - shift) * NBBY;
4732 addr &= ~(sizeof(uint32_t) - 1);
4733 mask = VM_PAGE_BITS_ALL << shift;
4738 new |= newbits << shift;
4739 } while (atomic_fcmpset_32((uint32_t *)addr, &old, new) == 0);
4740 return (old >> shift);
4741 #endif /* PAGE_SIZE */
4745 * vm_page_set_valid_range:
4747 * Sets portions of a page valid. The arguments are expected
4748 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive
4749 * of any partial chunks touched by the range. The invalid portion of
4750 * such chunks will be zeroed.
4752 * (base + size) must be less then or equal to PAGE_SIZE.
4755 vm_page_set_valid_range(vm_page_t m, int base, int size)
4758 vm_page_bits_t pagebits;
4760 vm_page_assert_busied(m);
4761 if (size == 0) /* handle degenerate case */
4765 * If the base is not DEV_BSIZE aligned and the valid
4766 * bit is clear, we have to zero out a portion of the
4769 if ((frag = rounddown2(base, DEV_BSIZE)) != base &&
4770 (m->valid & (1 << (base >> DEV_BSHIFT))) == 0)
4771 pmap_zero_page_area(m, frag, base - frag);
4774 * If the ending offset is not DEV_BSIZE aligned and the
4775 * valid bit is clear, we have to zero out a portion of
4778 endoff = base + size;
4779 if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff &&
4780 (m->valid & (1 << (endoff >> DEV_BSHIFT))) == 0)
4781 pmap_zero_page_area(m, endoff,
4782 DEV_BSIZE - (endoff & (DEV_BSIZE - 1)));
4785 * Assert that no previously invalid block that is now being validated
4788 KASSERT((~m->valid & vm_page_bits(base, size) & m->dirty) == 0,
4789 ("vm_page_set_valid_range: page %p is dirty", m));
4792 * Set valid bits inclusive of any overlap.
4794 pagebits = vm_page_bits(base, size);
4795 if (vm_page_xbusied(m))
4796 m->valid |= pagebits;
4798 vm_page_bits_set(m, &m->valid, pagebits);
4802 * Set the page dirty bits and free the invalid swap space if
4803 * present. Returns the previous dirty bits.
4806 vm_page_set_dirty(vm_page_t m)
4810 VM_PAGE_OBJECT_BUSY_ASSERT(m);
4812 if (vm_page_xbusied(m) && !pmap_page_is_write_mapped(m)) {
4814 m->dirty = VM_PAGE_BITS_ALL;
4816 old = vm_page_bits_swap(m, &m->dirty, VM_PAGE_BITS_ALL);
4817 if (old == 0 && (m->a.flags & PGA_SWAP_SPACE) != 0)
4818 vm_pager_page_unswapped(m);
4824 * Clear the given bits from the specified page's dirty field.
4826 static __inline void
4827 vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits)
4830 vm_page_assert_busied(m);
4833 * If the page is xbusied and not write mapped we are the
4834 * only thread that can modify dirty bits. Otherwise, The pmap
4835 * layer can call vm_page_dirty() without holding a distinguished
4836 * lock. The combination of page busy and atomic operations
4837 * suffice to guarantee consistency of the page dirty field.
4839 if (vm_page_xbusied(m) && !pmap_page_is_write_mapped(m))
4840 m->dirty &= ~pagebits;
4842 vm_page_bits_clear(m, &m->dirty, pagebits);
4846 * vm_page_set_validclean:
4848 * Sets portions of a page valid and clean. The arguments are expected
4849 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive
4850 * of any partial chunks touched by the range. The invalid portion of
4851 * such chunks will be zero'd.
4853 * (base + size) must be less then or equal to PAGE_SIZE.
4856 vm_page_set_validclean(vm_page_t m, int base, int size)
4858 vm_page_bits_t oldvalid, pagebits;
4861 vm_page_assert_busied(m);
4862 if (size == 0) /* handle degenerate case */
4866 * If the base is not DEV_BSIZE aligned and the valid
4867 * bit is clear, we have to zero out a portion of the
4870 if ((frag = rounddown2(base, DEV_BSIZE)) != base &&
4871 (m->valid & ((vm_page_bits_t)1 << (base >> DEV_BSHIFT))) == 0)
4872 pmap_zero_page_area(m, frag, base - frag);
4875 * If the ending offset is not DEV_BSIZE aligned and the
4876 * valid bit is clear, we have to zero out a portion of
4879 endoff = base + size;
4880 if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff &&
4881 (m->valid & ((vm_page_bits_t)1 << (endoff >> DEV_BSHIFT))) == 0)
4882 pmap_zero_page_area(m, endoff,
4883 DEV_BSIZE - (endoff & (DEV_BSIZE - 1)));
4886 * Set valid, clear dirty bits. If validating the entire
4887 * page we can safely clear the pmap modify bit. We also
4888 * use this opportunity to clear the PGA_NOSYNC flag. If a process
4889 * takes a write fault on a MAP_NOSYNC memory area the flag will
4892 * We set valid bits inclusive of any overlap, but we can only
4893 * clear dirty bits for DEV_BSIZE chunks that are fully within
4896 oldvalid = m->valid;
4897 pagebits = vm_page_bits(base, size);
4898 if (vm_page_xbusied(m))
4899 m->valid |= pagebits;
4901 vm_page_bits_set(m, &m->valid, pagebits);
4903 if ((frag = base & (DEV_BSIZE - 1)) != 0) {
4904 frag = DEV_BSIZE - frag;
4910 pagebits = vm_page_bits(base, size & (DEV_BSIZE - 1));
4912 if (base == 0 && size == PAGE_SIZE) {
4914 * The page can only be modified within the pmap if it is
4915 * mapped, and it can only be mapped if it was previously
4918 if (oldvalid == VM_PAGE_BITS_ALL)
4920 * Perform the pmap_clear_modify() first. Otherwise,
4921 * a concurrent pmap operation, such as
4922 * pmap_protect(), could clear a modification in the
4923 * pmap and set the dirty field on the page before
4924 * pmap_clear_modify() had begun and after the dirty
4925 * field was cleared here.
4927 pmap_clear_modify(m);
4929 vm_page_aflag_clear(m, PGA_NOSYNC);
4930 } else if (oldvalid != VM_PAGE_BITS_ALL && vm_page_xbusied(m))
4931 m->dirty &= ~pagebits;
4933 vm_page_clear_dirty_mask(m, pagebits);
4937 vm_page_clear_dirty(vm_page_t m, int base, int size)
4940 vm_page_clear_dirty_mask(m, vm_page_bits(base, size));
4944 * vm_page_set_invalid:
4946 * Invalidates DEV_BSIZE'd chunks within a page. Both the
4947 * valid and dirty bits for the effected areas are cleared.
4950 vm_page_set_invalid(vm_page_t m, int base, int size)
4952 vm_page_bits_t bits;
4956 * The object lock is required so that pages can't be mapped
4957 * read-only while we're in the process of invalidating them.
4960 VM_OBJECT_ASSERT_WLOCKED(object);
4961 vm_page_assert_busied(m);
4963 if (object->type == OBJT_VNODE && base == 0 && IDX_TO_OFF(m->pindex) +
4964 size >= object->un_pager.vnp.vnp_size)
4965 bits = VM_PAGE_BITS_ALL;
4967 bits = vm_page_bits(base, size);
4968 if (object->ref_count != 0 && vm_page_all_valid(m) && bits != 0)
4970 KASSERT((bits == 0 && vm_page_all_valid(m)) ||
4971 !pmap_page_is_mapped(m),
4972 ("vm_page_set_invalid: page %p is mapped", m));
4973 if (vm_page_xbusied(m)) {
4977 vm_page_bits_clear(m, &m->valid, bits);
4978 vm_page_bits_clear(m, &m->dirty, bits);
4985 * Invalidates the entire page. The page must be busy, unmapped, and
4986 * the enclosing object must be locked. The object locks protects
4987 * against concurrent read-only pmap enter which is done without
4991 vm_page_invalid(vm_page_t m)
4994 vm_page_assert_busied(m);
4995 VM_OBJECT_ASSERT_LOCKED(m->object);
4996 MPASS(!pmap_page_is_mapped(m));
4998 if (vm_page_xbusied(m))
5001 vm_page_bits_clear(m, &m->valid, VM_PAGE_BITS_ALL);
5005 * vm_page_zero_invalid()
5007 * The kernel assumes that the invalid portions of a page contain
5008 * garbage, but such pages can be mapped into memory by user code.
5009 * When this occurs, we must zero out the non-valid portions of the
5010 * page so user code sees what it expects.
5012 * Pages are most often semi-valid when the end of a file is mapped
5013 * into memory and the file's size is not page aligned.
5016 vm_page_zero_invalid(vm_page_t m, boolean_t setvalid)
5022 * Scan the valid bits looking for invalid sections that
5023 * must be zeroed. Invalid sub-DEV_BSIZE'd areas ( where the
5024 * valid bit may be set ) have already been zeroed by
5025 * vm_page_set_validclean().
5027 for (b = i = 0; i <= PAGE_SIZE / DEV_BSIZE; ++i) {
5028 if (i == (PAGE_SIZE / DEV_BSIZE) ||
5029 (m->valid & ((vm_page_bits_t)1 << i))) {
5031 pmap_zero_page_area(m,
5032 b << DEV_BSHIFT, (i - b) << DEV_BSHIFT);
5039 * setvalid is TRUE when we can safely set the zero'd areas
5040 * as being valid. We can do this if there are no cache consistancy
5041 * issues. e.g. it is ok to do with UFS, but not ok to do with NFS.
5050 * Is (partial) page valid? Note that the case where size == 0
5051 * will return FALSE in the degenerate case where the page is
5052 * entirely invalid, and TRUE otherwise.
5054 * Some callers envoke this routine without the busy lock held and
5055 * handle races via higher level locks. Typical callers should
5056 * hold a busy lock to prevent invalidation.
5059 vm_page_is_valid(vm_page_t m, int base, int size)
5061 vm_page_bits_t bits;
5063 bits = vm_page_bits(base, size);
5064 return (m->valid != 0 && (m->valid & bits) == bits);
5068 * Returns true if all of the specified predicates are true for the entire
5069 * (super)page and false otherwise.
5072 vm_page_ps_test(vm_page_t m, int flags, vm_page_t skip_m)
5078 if (skip_m != NULL && skip_m->object != object)
5080 VM_OBJECT_ASSERT_LOCKED(object);
5081 npages = atop(pagesizes[m->psind]);
5084 * The physically contiguous pages that make up a superpage, i.e., a
5085 * page with a page size index ("psind") greater than zero, will
5086 * occupy adjacent entries in vm_page_array[].
5088 for (i = 0; i < npages; i++) {
5089 /* Always test object consistency, including "skip_m". */
5090 if (m[i].object != object)
5092 if (&m[i] == skip_m)
5094 if ((flags & PS_NONE_BUSY) != 0 && vm_page_busied(&m[i]))
5096 if ((flags & PS_ALL_DIRTY) != 0) {
5098 * Calling vm_page_test_dirty() or pmap_is_modified()
5099 * might stop this case from spuriously returning
5100 * "false". However, that would require a write lock
5101 * on the object containing "m[i]".
5103 if (m[i].dirty != VM_PAGE_BITS_ALL)
5106 if ((flags & PS_ALL_VALID) != 0 &&
5107 m[i].valid != VM_PAGE_BITS_ALL)
5114 * Set the page's dirty bits if the page is modified.
5117 vm_page_test_dirty(vm_page_t m)
5120 vm_page_assert_busied(m);
5121 if (m->dirty != VM_PAGE_BITS_ALL && pmap_is_modified(m))
5126 vm_page_valid(vm_page_t m)
5129 vm_page_assert_busied(m);
5130 if (vm_page_xbusied(m))
5131 m->valid = VM_PAGE_BITS_ALL;
5133 vm_page_bits_set(m, &m->valid, VM_PAGE_BITS_ALL);
5137 vm_page_lock_KBI(vm_page_t m, const char *file, int line)
5140 mtx_lock_flags_(vm_page_lockptr(m), 0, file, line);
5144 vm_page_unlock_KBI(vm_page_t m, const char *file, int line)
5147 mtx_unlock_flags_(vm_page_lockptr(m), 0, file, line);
5151 vm_page_trylock_KBI(vm_page_t m, const char *file, int line)
5154 return (mtx_trylock_flags_(vm_page_lockptr(m), 0, file, line));
5157 #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
5159 vm_page_assert_locked_KBI(vm_page_t m, const char *file, int line)
5162 vm_page_lock_assert_KBI(m, MA_OWNED, file, line);
5166 vm_page_lock_assert_KBI(vm_page_t m, int a, const char *file, int line)
5169 mtx_assert_(vm_page_lockptr(m), a, file, line);
5175 vm_page_object_busy_assert(vm_page_t m)
5179 * Certain of the page's fields may only be modified by the
5180 * holder of a page or object busy.
5182 if (m->object != NULL && !vm_page_busied(m))
5183 VM_OBJECT_ASSERT_BUSY(m->object);
5187 vm_page_assert_pga_writeable(vm_page_t m, uint16_t bits)
5190 if ((bits & PGA_WRITEABLE) == 0)
5194 * The PGA_WRITEABLE flag can only be set if the page is
5195 * managed, is exclusively busied or the object is locked.
5196 * Currently, this flag is only set by pmap_enter().
5198 KASSERT((m->oflags & VPO_UNMANAGED) == 0,
5199 ("PGA_WRITEABLE on unmanaged page"));
5200 if (!vm_page_xbusied(m))
5201 VM_OBJECT_ASSERT_BUSY(m->object);
5205 #include "opt_ddb.h"
5207 #include <sys/kernel.h>
5209 #include <ddb/ddb.h>
5211 DB_SHOW_COMMAND(page, vm_page_print_page_info)
5214 db_printf("vm_cnt.v_free_count: %d\n", vm_free_count());
5215 db_printf("vm_cnt.v_inactive_count: %d\n", vm_inactive_count());
5216 db_printf("vm_cnt.v_active_count: %d\n", vm_active_count());
5217 db_printf("vm_cnt.v_laundry_count: %d\n", vm_laundry_count());
5218 db_printf("vm_cnt.v_wire_count: %d\n", vm_wire_count());
5219 db_printf("vm_cnt.v_free_reserved: %d\n", vm_cnt.v_free_reserved);
5220 db_printf("vm_cnt.v_free_min: %d\n", vm_cnt.v_free_min);
5221 db_printf("vm_cnt.v_free_target: %d\n", vm_cnt.v_free_target);
5222 db_printf("vm_cnt.v_inactive_target: %d\n", vm_cnt.v_inactive_target);
5225 DB_SHOW_COMMAND(pageq, vm_page_print_pageq_info)
5229 db_printf("pq_free %d\n", vm_free_count());
5230 for (dom = 0; dom < vm_ndomains; dom++) {
5232 "dom %d page_cnt %d free %d pq_act %d pq_inact %d pq_laund %d pq_unsw %d\n",
5234 vm_dom[dom].vmd_page_count,
5235 vm_dom[dom].vmd_free_count,
5236 vm_dom[dom].vmd_pagequeues[PQ_ACTIVE].pq_cnt,
5237 vm_dom[dom].vmd_pagequeues[PQ_INACTIVE].pq_cnt,
5238 vm_dom[dom].vmd_pagequeues[PQ_LAUNDRY].pq_cnt,
5239 vm_dom[dom].vmd_pagequeues[PQ_UNSWAPPABLE].pq_cnt);
5243 DB_SHOW_COMMAND(pginfo, vm_page_print_pginfo)
5246 boolean_t phys, virt;
5249 db_printf("show pginfo addr\n");
5253 phys = strchr(modif, 'p') != NULL;
5254 virt = strchr(modif, 'v') != NULL;
5256 m = PHYS_TO_VM_PAGE(pmap_kextract(addr));
5258 m = PHYS_TO_VM_PAGE(addr);
5260 m = (vm_page_t)addr;
5262 "page %p obj %p pidx 0x%jx phys 0x%jx q %d ref %u\n"
5263 " af 0x%x of 0x%x f 0x%x act %d busy %x valid 0x%x dirty 0x%x\n",
5264 m, m->object, (uintmax_t)m->pindex, (uintmax_t)m->phys_addr,
5265 m->a.queue, m->ref_count, m->a.flags, m->oflags,
5266 m->flags, m->a.act_count, m->busy_lock, m->valid, m->dirty);