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>
77 #include <sys/domainset.h>
78 #include <sys/kernel.h>
79 #include <sys/limits.h>
80 #include <sys/linker.h>
81 #include <sys/malloc.h>
83 #include <sys/msgbuf.h>
84 #include <sys/mutex.h>
86 #include <sys/rwlock.h>
88 #include <sys/sched.h>
90 #include <sys/sysctl.h>
91 #include <sys/vmmeter.h>
92 #include <sys/vnode.h>
96 #include <vm/vm_param.h>
97 #include <vm/vm_domainset.h>
98 #include <vm/vm_kern.h>
99 #include <vm/vm_map.h>
100 #include <vm/vm_object.h>
101 #include <vm/vm_page.h>
102 #include <vm/vm_pageout.h>
103 #include <vm/vm_phys.h>
104 #include <vm/vm_pagequeue.h>
105 #include <vm/vm_pager.h>
106 #include <vm/vm_radix.h>
107 #include <vm/vm_reserv.h>
108 #include <vm/vm_extern.h>
110 #include <vm/uma_int.h>
112 #include <machine/md_var.h>
114 extern int uma_startup_count(int);
115 extern void uma_startup(void *, int);
116 extern int vmem_startup_count(void);
118 struct vm_domain vm_dom[MAXMEMDOM];
120 DPCPU_DEFINE_STATIC(struct vm_batchqueue, pqbatch[MAXMEMDOM][PQ_COUNT]);
122 struct mtx_padalign __exclusive_cache_line pa_lock[PA_LOCK_COUNT];
124 struct mtx_padalign __exclusive_cache_line vm_domainset_lock;
125 /* The following fields are protected by the domainset lock. */
126 domainset_t __exclusive_cache_line vm_min_domains;
127 domainset_t __exclusive_cache_line vm_severe_domains;
128 static int vm_min_waiters;
129 static int vm_severe_waiters;
130 static int vm_pageproc_waiters;
133 * bogus page -- for I/O to/from partially complete buffers,
134 * or for paging into sparsely invalid regions.
136 vm_page_t bogus_page;
138 vm_page_t vm_page_array;
139 long vm_page_array_size;
142 static int boot_pages;
143 SYSCTL_INT(_vm, OID_AUTO, boot_pages, CTLFLAG_RDTUN | CTLFLAG_NOFETCH,
145 "number of pages allocated for bootstrapping the VM system");
147 static int pa_tryrelock_restart;
148 SYSCTL_INT(_vm, OID_AUTO, tryrelock_restart, CTLFLAG_RD,
149 &pa_tryrelock_restart, 0, "Number of tryrelock restarts");
151 static TAILQ_HEAD(, vm_page) blacklist_head;
152 static int sysctl_vm_page_blacklist(SYSCTL_HANDLER_ARGS);
153 SYSCTL_PROC(_vm, OID_AUTO, page_blacklist, CTLTYPE_STRING | CTLFLAG_RD |
154 CTLFLAG_MPSAFE, NULL, 0, sysctl_vm_page_blacklist, "A", "Blacklist pages");
156 static uma_zone_t fakepg_zone;
158 static void vm_page_alloc_check(vm_page_t m);
159 static void vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits);
160 static void vm_page_dequeue_complete(vm_page_t m);
161 static void vm_page_enqueue(vm_page_t m, uint8_t queue);
162 static void vm_page_init(void *dummy);
163 static int vm_page_insert_after(vm_page_t m, vm_object_t object,
164 vm_pindex_t pindex, vm_page_t mpred);
165 static void vm_page_insert_radixdone(vm_page_t m, vm_object_t object,
167 static int vm_page_reclaim_run(int req_class, int domain, u_long npages,
168 vm_page_t m_run, vm_paddr_t high);
169 static int vm_domain_alloc_fail(struct vm_domain *vmd, vm_object_t object,
171 static int vm_page_zone_import(void *arg, void **store, int cnt, int domain,
173 static void vm_page_zone_release(void *arg, void **store, int cnt);
175 SYSINIT(vm_page, SI_SUB_VM, SI_ORDER_SECOND, vm_page_init, NULL);
178 vm_page_init(void *dummy)
181 fakepg_zone = uma_zcreate("fakepg", sizeof(struct vm_page), NULL, NULL,
182 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE | UMA_ZONE_VM);
183 bogus_page = vm_page_alloc(NULL, 0, VM_ALLOC_NOOBJ |
184 VM_ALLOC_NORMAL | VM_ALLOC_WIRED);
188 * The cache page zone is initialized later since we need to be able to allocate
189 * pages before UMA is fully initialized.
192 vm_page_init_cache_zones(void *dummy __unused)
194 struct vm_domain *vmd;
195 struct vm_pgcache *pgcache;
198 for (domain = 0; domain < vm_ndomains; domain++) {
199 vmd = VM_DOMAIN(domain);
202 * Don't allow the page caches to take up more than .25% of
205 if (vmd->vmd_page_count / 400 < 256 * mp_ncpus * VM_NFREEPOOL)
207 for (pool = 0; pool < VM_NFREEPOOL; pool++) {
208 pgcache = &vmd->vmd_pgcache[pool];
209 pgcache->domain = domain;
210 pgcache->pool = pool;
211 pgcache->zone = uma_zcache_create("vm pgcache",
212 sizeof(struct vm_page), NULL, NULL, NULL, NULL,
213 vm_page_zone_import, vm_page_zone_release, pgcache,
214 UMA_ZONE_NOBUCKETCACHE | UMA_ZONE_MAXBUCKET |
219 SYSINIT(vm_page2, SI_SUB_VM_CONF, SI_ORDER_ANY, vm_page_init_cache_zones, NULL);
221 /* Make sure that u_long is at least 64 bits when PAGE_SIZE is 32K. */
222 #if PAGE_SIZE == 32768
224 CTASSERT(sizeof(u_long) >= 8);
229 * Try to acquire a physical address lock while a pmap is locked. If we
230 * fail to trylock we unlock and lock the pmap directly and cache the
231 * locked pa in *locked. The caller should then restart their loop in case
232 * the virtual to physical mapping has changed.
235 vm_page_pa_tryrelock(pmap_t pmap, vm_paddr_t pa, vm_paddr_t *locked)
242 PA_LOCK_ASSERT(lockpa, MA_OWNED);
243 if (PA_LOCKPTR(pa) == PA_LOCKPTR(lockpa))
250 atomic_add_int(&pa_tryrelock_restart, 1);
259 * Sets the page size, perhaps based upon the memory
260 * size. Must be called before any use of page-size
261 * dependent functions.
264 vm_set_page_size(void)
266 if (vm_cnt.v_page_size == 0)
267 vm_cnt.v_page_size = PAGE_SIZE;
268 if (((vm_cnt.v_page_size - 1) & vm_cnt.v_page_size) != 0)
269 panic("vm_set_page_size: page size not a power of two");
273 * vm_page_blacklist_next:
275 * Find the next entry in the provided string of blacklist
276 * addresses. Entries are separated by space, comma, or newline.
277 * If an invalid integer is encountered then the rest of the
278 * string is skipped. Updates the list pointer to the next
279 * character, or NULL if the string is exhausted or invalid.
282 vm_page_blacklist_next(char **list, char *end)
287 if (list == NULL || *list == NULL)
295 * If there's no end pointer then the buffer is coming from
296 * the kenv and we know it's null-terminated.
299 end = *list + strlen(*list);
301 /* Ensure that strtoq() won't walk off the end */
303 if (*end == '\n' || *end == ' ' || *end == ',')
306 printf("Blacklist not terminated, skipping\n");
312 for (pos = *list; *pos != '\0'; pos = cp) {
313 bad = strtoq(pos, &cp, 0);
314 if (*cp == '\0' || *cp == ' ' || *cp == ',' || *cp == '\n') {
323 if (*cp == '\0' || ++cp >= end)
327 return (trunc_page(bad));
329 printf("Garbage in RAM blacklist, skipping\n");
335 vm_page_blacklist_add(vm_paddr_t pa, bool verbose)
337 struct vm_domain *vmd;
341 m = vm_phys_paddr_to_vm_page(pa);
343 return (true); /* page does not exist, no failure */
345 vmd = vm_pagequeue_domain(m);
346 vm_domain_free_lock(vmd);
347 ret = vm_phys_unfree_page(m);
348 vm_domain_free_unlock(vmd);
350 vm_domain_freecnt_inc(vmd, -1);
351 TAILQ_INSERT_TAIL(&blacklist_head, m, listq);
353 printf("Skipping page with pa 0x%jx\n", (uintmax_t)pa);
359 * vm_page_blacklist_check:
361 * Iterate through the provided string of blacklist addresses, pulling
362 * each entry out of the physical allocator free list and putting it
363 * onto a list for reporting via the vm.page_blacklist sysctl.
366 vm_page_blacklist_check(char *list, char *end)
372 while (next != NULL) {
373 if ((pa = vm_page_blacklist_next(&next, end)) == 0)
375 vm_page_blacklist_add(pa, bootverbose);
380 * vm_page_blacklist_load:
382 * Search for a special module named "ram_blacklist". It'll be a
383 * plain text file provided by the user via the loader directive
387 vm_page_blacklist_load(char **list, char **end)
396 mod = preload_search_by_type("ram_blacklist");
398 ptr = preload_fetch_addr(mod);
399 len = preload_fetch_size(mod);
410 sysctl_vm_page_blacklist(SYSCTL_HANDLER_ARGS)
417 error = sysctl_wire_old_buffer(req, 0);
420 sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
421 TAILQ_FOREACH(m, &blacklist_head, listq) {
422 sbuf_printf(&sbuf, "%s%#jx", first ? "" : ",",
423 (uintmax_t)m->phys_addr);
426 error = sbuf_finish(&sbuf);
432 * Initialize a dummy page for use in scans of the specified paging queue.
433 * In principle, this function only needs to set the flag PG_MARKER.
434 * Nonetheless, it write busies and initializes the hold count to one as
435 * safety precautions.
438 vm_page_init_marker(vm_page_t marker, int queue, uint8_t aflags)
441 bzero(marker, sizeof(*marker));
442 marker->flags = PG_MARKER;
443 marker->aflags = aflags;
444 marker->busy_lock = VPB_SINGLE_EXCLUSIVER;
445 marker->queue = queue;
446 marker->hold_count = 1;
450 vm_page_domain_init(int domain)
452 struct vm_domain *vmd;
453 struct vm_pagequeue *pq;
456 vmd = VM_DOMAIN(domain);
457 bzero(vmd, sizeof(*vmd));
458 *__DECONST(char **, &vmd->vmd_pagequeues[PQ_INACTIVE].pq_name) =
459 "vm inactive pagequeue";
460 *__DECONST(char **, &vmd->vmd_pagequeues[PQ_ACTIVE].pq_name) =
461 "vm active pagequeue";
462 *__DECONST(char **, &vmd->vmd_pagequeues[PQ_LAUNDRY].pq_name) =
463 "vm laundry pagequeue";
464 *__DECONST(char **, &vmd->vmd_pagequeues[PQ_UNSWAPPABLE].pq_name) =
465 "vm unswappable pagequeue";
466 vmd->vmd_domain = domain;
467 vmd->vmd_page_count = 0;
468 vmd->vmd_free_count = 0;
470 vmd->vmd_oom = FALSE;
471 for (i = 0; i < PQ_COUNT; i++) {
472 pq = &vmd->vmd_pagequeues[i];
473 TAILQ_INIT(&pq->pq_pl);
474 mtx_init(&pq->pq_mutex, pq->pq_name, "vm pagequeue",
475 MTX_DEF | MTX_DUPOK);
477 vm_page_init_marker(&vmd->vmd_markers[i], i, 0);
479 mtx_init(&vmd->vmd_free_mtx, "vm page free queue", NULL, MTX_DEF);
480 mtx_init(&vmd->vmd_pageout_mtx, "vm pageout lock", NULL, MTX_DEF);
481 snprintf(vmd->vmd_name, sizeof(vmd->vmd_name), "%d", domain);
484 * inacthead is used to provide FIFO ordering for LRU-bypassing
487 vm_page_init_marker(&vmd->vmd_inacthead, PQ_INACTIVE, PGA_ENQUEUED);
488 TAILQ_INSERT_HEAD(&vmd->vmd_pagequeues[PQ_INACTIVE].pq_pl,
489 &vmd->vmd_inacthead, plinks.q);
492 * The clock pages are used to implement active queue scanning without
493 * requeues. Scans start at clock[0], which is advanced after the scan
494 * ends. When the two clock hands meet, they are reset and scanning
495 * resumes from the head of the queue.
497 vm_page_init_marker(&vmd->vmd_clock[0], PQ_ACTIVE, PGA_ENQUEUED);
498 vm_page_init_marker(&vmd->vmd_clock[1], PQ_ACTIVE, PGA_ENQUEUED);
499 TAILQ_INSERT_HEAD(&vmd->vmd_pagequeues[PQ_ACTIVE].pq_pl,
500 &vmd->vmd_clock[0], plinks.q);
501 TAILQ_INSERT_TAIL(&vmd->vmd_pagequeues[PQ_ACTIVE].pq_pl,
502 &vmd->vmd_clock[1], plinks.q);
506 * Initialize a physical page in preparation for adding it to the free
510 vm_page_init_page(vm_page_t m, vm_paddr_t pa, int segind)
515 m->busy_lock = VPB_UNBUSIED;
517 m->flags = m->aflags = 0;
522 m->order = VM_NFREEORDER;
523 m->pool = VM_FREEPOOL_DEFAULT;
524 m->valid = m->dirty = 0;
531 * Initializes the resident memory module. Allocates physical memory for
532 * bootstrapping UMA and some data structures that are used to manage
533 * physical pages. Initializes these structures, and populates the free
537 vm_page_startup(vm_offset_t vaddr)
539 struct vm_phys_seg *seg;
541 char *list, *listend;
543 vm_paddr_t end, high_avail, low_avail, new_end, page_range, size;
544 vm_paddr_t biggestsize, last_pa, pa;
546 int biggestone, i, segind;
547 #if defined(__i386__) && defined(VM_PHYSSEG_DENSE)
553 vaddr = round_page(vaddr);
555 for (i = 0; phys_avail[i + 1]; i += 2) {
556 phys_avail[i] = round_page(phys_avail[i]);
557 phys_avail[i + 1] = trunc_page(phys_avail[i + 1]);
559 for (i = 0; phys_avail[i + 1]; i += 2) {
560 size = phys_avail[i + 1] - phys_avail[i];
561 if (size > biggestsize) {
567 end = phys_avail[biggestone+1];
570 * Initialize the page and queue locks.
572 mtx_init(&vm_domainset_lock, "vm domainset lock", NULL, MTX_DEF);
573 for (i = 0; i < PA_LOCK_COUNT; i++)
574 mtx_init(&pa_lock[i], "vm page", NULL, MTX_DEF);
575 for (i = 0; i < vm_ndomains; i++)
576 vm_page_domain_init(i);
579 * Allocate memory for use when boot strapping the kernel memory
580 * allocator. Tell UMA how many zones we are going to create
581 * before going fully functional. UMA will add its zones.
583 * VM startup zones: vmem, vmem_btag, VM OBJECT, RADIX NODE, MAP,
584 * KMAP ENTRY, MAP ENTRY, VMSPACE.
586 boot_pages = uma_startup_count(8);
588 #ifndef UMA_MD_SMALL_ALLOC
589 /* vmem_startup() calls uma_prealloc(). */
590 boot_pages += vmem_startup_count();
591 /* vm_map_startup() calls uma_prealloc(). */
592 boot_pages += howmany(MAX_KMAP,
593 UMA_SLAB_SPACE / sizeof(struct vm_map));
596 * Before going fully functional kmem_init() does allocation
597 * from "KMAP ENTRY" and vmem_create() does allocation from "vmem".
602 * CTFLAG_RDTUN doesn't work during the early boot process, so we must
603 * manually fetch the value.
605 TUNABLE_INT_FETCH("vm.boot_pages", &boot_pages);
606 new_end = end - (boot_pages * UMA_SLAB_SIZE);
607 new_end = trunc_page(new_end);
608 mapped = pmap_map(&vaddr, new_end, end,
609 VM_PROT_READ | VM_PROT_WRITE);
610 bzero((void *)mapped, end - new_end);
611 uma_startup((void *)mapped, boot_pages);
615 new_end = end - round_page(witness_startup_count());
616 mapped = pmap_map(&vaddr, new_end, end,
617 VM_PROT_READ | VM_PROT_WRITE);
618 bzero((void *)mapped, end - new_end);
619 witness_startup((void *)mapped);
622 #if defined(__aarch64__) || defined(__amd64__) || defined(__arm__) || \
623 defined(__i386__) || defined(__mips__) || defined(__riscv)
625 * Allocate a bitmap to indicate that a random physical page
626 * needs to be included in a minidump.
628 * The amd64 port needs this to indicate which direct map pages
629 * need to be dumped, via calls to dump_add_page()/dump_drop_page().
631 * However, i386 still needs this workspace internally within the
632 * minidump code. In theory, they are not needed on i386, but are
633 * included should the sf_buf code decide to use them.
636 for (i = 0; dump_avail[i + 1] != 0; i += 2)
637 if (dump_avail[i + 1] > last_pa)
638 last_pa = dump_avail[i + 1];
639 page_range = last_pa / PAGE_SIZE;
640 vm_page_dump_size = round_page(roundup2(page_range, NBBY) / NBBY);
641 new_end -= vm_page_dump_size;
642 vm_page_dump = (void *)(uintptr_t)pmap_map(&vaddr, new_end,
643 new_end + vm_page_dump_size, VM_PROT_READ | VM_PROT_WRITE);
644 bzero((void *)vm_page_dump, vm_page_dump_size);
648 #if defined(__aarch64__) || defined(__amd64__) || defined(__mips__) || \
651 * Include the UMA bootstrap pages and vm_page_dump in a crash dump.
652 * When pmap_map() uses the direct map, they are not automatically
655 for (pa = new_end; pa < end; pa += PAGE_SIZE)
658 phys_avail[biggestone + 1] = new_end;
661 * Request that the physical pages underlying the message buffer be
662 * included in a crash dump. Since the message buffer is accessed
663 * through the direct map, they are not automatically included.
665 pa = DMAP_TO_PHYS((vm_offset_t)msgbufp->msg_ptr);
666 last_pa = pa + round_page(msgbufsize);
667 while (pa < last_pa) {
673 * Compute the number of pages of memory that will be available for
674 * use, taking into account the overhead of a page structure per page.
675 * In other words, solve
676 * "available physical memory" - round_page(page_range *
677 * sizeof(struct vm_page)) = page_range * PAGE_SIZE
680 low_avail = phys_avail[0];
681 high_avail = phys_avail[1];
682 for (i = 0; i < vm_phys_nsegs; i++) {
683 if (vm_phys_segs[i].start < low_avail)
684 low_avail = vm_phys_segs[i].start;
685 if (vm_phys_segs[i].end > high_avail)
686 high_avail = vm_phys_segs[i].end;
688 /* Skip the first chunk. It is already accounted for. */
689 for (i = 2; phys_avail[i + 1] != 0; i += 2) {
690 if (phys_avail[i] < low_avail)
691 low_avail = phys_avail[i];
692 if (phys_avail[i + 1] > high_avail)
693 high_avail = phys_avail[i + 1];
695 first_page = low_avail / PAGE_SIZE;
696 #ifdef VM_PHYSSEG_SPARSE
698 for (i = 0; i < vm_phys_nsegs; i++)
699 size += vm_phys_segs[i].end - vm_phys_segs[i].start;
700 for (i = 0; phys_avail[i + 1] != 0; i += 2)
701 size += phys_avail[i + 1] - phys_avail[i];
702 #elif defined(VM_PHYSSEG_DENSE)
703 size = high_avail - low_avail;
705 #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined."
708 #ifdef VM_PHYSSEG_DENSE
710 * In the VM_PHYSSEG_DENSE case, the number of pages can account for
711 * the overhead of a page structure per page only if vm_page_array is
712 * allocated from the last physical memory chunk. Otherwise, we must
713 * allocate page structures representing the physical memory
714 * underlying vm_page_array, even though they will not be used.
716 if (new_end != high_avail)
717 page_range = size / PAGE_SIZE;
721 page_range = size / (PAGE_SIZE + sizeof(struct vm_page));
724 * If the partial bytes remaining are large enough for
725 * a page (PAGE_SIZE) without a corresponding
726 * 'struct vm_page', then new_end will contain an
727 * extra page after subtracting the length of the VM
728 * page array. Compensate by subtracting an extra
731 if (size % (PAGE_SIZE + sizeof(struct vm_page)) >= PAGE_SIZE) {
732 if (new_end == high_avail)
733 high_avail -= PAGE_SIZE;
734 new_end -= PAGE_SIZE;
740 * Reserve an unmapped guard page to trap access to vm_page_array[-1].
741 * However, because this page is allocated from KVM, out-of-bounds
742 * accesses using the direct map will not be trapped.
747 * Allocate physical memory for the page structures, and map it.
749 new_end = trunc_page(end - page_range * sizeof(struct vm_page));
750 mapped = pmap_map(&vaddr, new_end, end,
751 VM_PROT_READ | VM_PROT_WRITE);
752 vm_page_array = (vm_page_t)mapped;
753 vm_page_array_size = page_range;
755 #if VM_NRESERVLEVEL > 0
757 * Allocate physical memory for the reservation management system's
758 * data structures, and map it.
760 if (high_avail == end)
761 high_avail = new_end;
762 new_end = vm_reserv_startup(&vaddr, new_end, high_avail);
764 #if defined(__aarch64__) || defined(__amd64__) || defined(__mips__) || \
767 * Include vm_page_array and vm_reserv_array in a crash dump.
769 for (pa = new_end; pa < end; pa += PAGE_SIZE)
772 phys_avail[biggestone + 1] = new_end;
775 * Add physical memory segments corresponding to the available
778 for (i = 0; phys_avail[i + 1] != 0; i += 2)
779 vm_phys_add_seg(phys_avail[i], phys_avail[i + 1]);
782 * Initialize the physical memory allocator.
787 * Initialize the page structures and add every available page to the
788 * physical memory allocator's free lists.
790 #if defined(__i386__) && defined(VM_PHYSSEG_DENSE)
791 for (ii = 0; ii < vm_page_array_size; ii++) {
792 m = &vm_page_array[ii];
793 vm_page_init_page(m, (first_page + ii) << PAGE_SHIFT, 0);
794 m->flags = PG_FICTITIOUS;
797 vm_cnt.v_page_count = 0;
798 for (segind = 0; segind < vm_phys_nsegs; segind++) {
799 seg = &vm_phys_segs[segind];
800 for (m = seg->first_page, pa = seg->start; pa < seg->end;
801 m++, pa += PAGE_SIZE)
802 vm_page_init_page(m, pa, segind);
805 * Add the segment to the free lists only if it is covered by
806 * one of the ranges in phys_avail. Because we've added the
807 * ranges to the vm_phys_segs array, we can assume that each
808 * segment is either entirely contained in one of the ranges,
809 * or doesn't overlap any of them.
811 for (i = 0; phys_avail[i + 1] != 0; i += 2) {
812 struct vm_domain *vmd;
814 if (seg->start < phys_avail[i] ||
815 seg->end > phys_avail[i + 1])
819 pagecount = (u_long)atop(seg->end - seg->start);
821 vmd = VM_DOMAIN(seg->domain);
822 vm_domain_free_lock(vmd);
823 vm_phys_free_contig(m, pagecount);
824 vm_domain_free_unlock(vmd);
825 vm_domain_freecnt_inc(vmd, pagecount);
826 vm_cnt.v_page_count += (u_int)pagecount;
828 vmd = VM_DOMAIN(seg->domain);
829 vmd->vmd_page_count += (u_int)pagecount;
830 vmd->vmd_segs |= 1UL << m->segind;
836 * Remove blacklisted pages from the physical memory allocator.
838 TAILQ_INIT(&blacklist_head);
839 vm_page_blacklist_load(&list, &listend);
840 vm_page_blacklist_check(list, listend);
842 list = kern_getenv("vm.blacklist");
843 vm_page_blacklist_check(list, NULL);
846 #if VM_NRESERVLEVEL > 0
848 * Initialize the reservation management system.
857 vm_page_reference(vm_page_t m)
860 vm_page_aflag_set(m, PGA_REFERENCED);
864 * vm_page_busy_downgrade:
866 * Downgrade an exclusive busy page into a single shared busy page.
869 vm_page_busy_downgrade(vm_page_t m)
874 vm_page_assert_xbusied(m);
875 locked = mtx_owned(vm_page_lockptr(m));
879 x &= VPB_BIT_WAITERS;
880 if (x != 0 && !locked)
882 if (atomic_cmpset_rel_int(&m->busy_lock,
883 VPB_SINGLE_EXCLUSIVER | x, VPB_SHARERS_WORD(1)))
885 if (x != 0 && !locked)
898 * Return a positive value if the page is shared busied, 0 otherwise.
901 vm_page_sbusied(vm_page_t m)
906 return ((x & VPB_BIT_SHARED) != 0 && x != VPB_UNBUSIED);
912 * Shared unbusy a page.
915 vm_page_sunbusy(vm_page_t m)
919 vm_page_lock_assert(m, MA_NOTOWNED);
920 vm_page_assert_sbusied(m);
924 if (VPB_SHARERS(x) > 1) {
925 if (atomic_cmpset_int(&m->busy_lock, x,
930 if ((x & VPB_BIT_WAITERS) == 0) {
931 KASSERT(x == VPB_SHARERS_WORD(1),
932 ("vm_page_sunbusy: invalid lock state"));
933 if (atomic_cmpset_int(&m->busy_lock,
934 VPB_SHARERS_WORD(1), VPB_UNBUSIED))
938 KASSERT(x == (VPB_SHARERS_WORD(1) | VPB_BIT_WAITERS),
939 ("vm_page_sunbusy: invalid lock state for waiters"));
942 if (!atomic_cmpset_int(&m->busy_lock, x, VPB_UNBUSIED)) {
953 * vm_page_busy_sleep:
955 * Sleep and release the page lock, using the page pointer as wchan.
956 * This is used to implement the hard-path of busying mechanism.
958 * The given page must be locked.
960 * If nonshared is true, sleep only if the page is xbusy.
963 vm_page_busy_sleep(vm_page_t m, const char *wmesg, bool nonshared)
967 vm_page_assert_locked(m);
970 if (x == VPB_UNBUSIED || (nonshared && (x & VPB_BIT_SHARED) != 0) ||
971 ((x & VPB_BIT_WAITERS) == 0 &&
972 !atomic_cmpset_int(&m->busy_lock, x, x | VPB_BIT_WAITERS))) {
976 msleep(m, vm_page_lockptr(m), PVM | PDROP, wmesg, 0);
982 * Try to shared busy a page.
983 * If the operation succeeds 1 is returned otherwise 0.
984 * The operation never sleeps.
987 vm_page_trysbusy(vm_page_t m)
993 if ((x & VPB_BIT_SHARED) == 0)
995 if (atomic_cmpset_acq_int(&m->busy_lock, x, x + VPB_ONE_SHARER))
1001 vm_page_xunbusy_locked(vm_page_t m)
1004 vm_page_assert_xbusied(m);
1005 vm_page_assert_locked(m);
1007 atomic_store_rel_int(&m->busy_lock, VPB_UNBUSIED);
1008 /* There is a waiter, do wakeup() instead of vm_page_flash(). */
1013 vm_page_xunbusy_maybelocked(vm_page_t m)
1017 vm_page_assert_xbusied(m);
1020 * Fast path for unbusy. If it succeeds, we know that there
1021 * are no waiters, so we do not need a wakeup.
1023 if (atomic_cmpset_rel_int(&m->busy_lock, VPB_SINGLE_EXCLUSIVER,
1027 lockacq = !mtx_owned(vm_page_lockptr(m));
1030 vm_page_xunbusy_locked(m);
1036 * vm_page_xunbusy_hard:
1038 * Called after the first try the exclusive unbusy of a page failed.
1039 * It is assumed that the waiters bit is on.
1042 vm_page_xunbusy_hard(vm_page_t m)
1045 vm_page_assert_xbusied(m);
1048 vm_page_xunbusy_locked(m);
1055 * Wakeup anyone waiting for the page.
1056 * The ownership bits do not change.
1058 * The given page must be locked.
1061 vm_page_flash(vm_page_t m)
1065 vm_page_lock_assert(m, MA_OWNED);
1069 if ((x & VPB_BIT_WAITERS) == 0)
1071 if (atomic_cmpset_int(&m->busy_lock, x,
1072 x & (~VPB_BIT_WAITERS)))
1079 * Avoid releasing and reacquiring the same page lock.
1082 vm_page_change_lock(vm_page_t m, struct mtx **mtx)
1086 mtx1 = vm_page_lockptr(m);
1096 * Keep page from being freed by the page daemon
1097 * much of the same effect as wiring, except much lower
1098 * overhead and should be used only for *very* temporary
1099 * holding ("wiring").
1102 vm_page_hold(vm_page_t mem)
1105 vm_page_lock_assert(mem, MA_OWNED);
1110 vm_page_unhold(vm_page_t mem)
1113 vm_page_lock_assert(mem, MA_OWNED);
1114 KASSERT(mem->hold_count >= 1, ("vm_page_unhold: hold count < 0!!!"));
1116 if (mem->hold_count == 0 && (mem->flags & PG_UNHOLDFREE) != 0)
1117 vm_page_free_toq(mem);
1121 * vm_page_unhold_pages:
1123 * Unhold each of the pages that is referenced by the given array.
1126 vm_page_unhold_pages(vm_page_t *ma, int count)
1131 for (; count != 0; count--) {
1132 vm_page_change_lock(*ma, &mtx);
1133 vm_page_unhold(*ma);
1141 PHYS_TO_VM_PAGE(vm_paddr_t pa)
1145 #ifdef VM_PHYSSEG_SPARSE
1146 m = vm_phys_paddr_to_vm_page(pa);
1148 m = vm_phys_fictitious_to_vm_page(pa);
1150 #elif defined(VM_PHYSSEG_DENSE)
1154 if (pi >= first_page && (pi - first_page) < vm_page_array_size) {
1155 m = &vm_page_array[pi - first_page];
1158 return (vm_phys_fictitious_to_vm_page(pa));
1160 #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined."
1167 * Create a fictitious page with the specified physical address and
1168 * memory attribute. The memory attribute is the only the machine-
1169 * dependent aspect of a fictitious page that must be initialized.
1172 vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr)
1176 m = uma_zalloc(fakepg_zone, M_WAITOK | M_ZERO);
1177 vm_page_initfake(m, paddr, memattr);
1182 vm_page_initfake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr)
1185 if ((m->flags & PG_FICTITIOUS) != 0) {
1187 * The page's memattr might have changed since the
1188 * previous initialization. Update the pmap to the
1193 m->phys_addr = paddr;
1195 /* Fictitious pages don't use "segind". */
1196 m->flags = PG_FICTITIOUS;
1197 /* Fictitious pages don't use "order" or "pool". */
1198 m->oflags = VPO_UNMANAGED;
1199 m->busy_lock = VPB_SINGLE_EXCLUSIVER;
1203 pmap_page_set_memattr(m, memattr);
1209 * Release a fictitious page.
1212 vm_page_putfake(vm_page_t m)
1215 KASSERT((m->oflags & VPO_UNMANAGED) != 0, ("managed %p", m));
1216 KASSERT((m->flags & PG_FICTITIOUS) != 0,
1217 ("vm_page_putfake: bad page %p", m));
1218 uma_zfree(fakepg_zone, m);
1222 * vm_page_updatefake:
1224 * Update the given fictitious page to the specified physical address and
1228 vm_page_updatefake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr)
1231 KASSERT((m->flags & PG_FICTITIOUS) != 0,
1232 ("vm_page_updatefake: bad page %p", m));
1233 m->phys_addr = paddr;
1234 pmap_page_set_memattr(m, memattr);
1243 vm_page_free(vm_page_t m)
1246 m->flags &= ~PG_ZERO;
1247 vm_page_free_toq(m);
1251 * vm_page_free_zero:
1253 * Free a page to the zerod-pages queue
1256 vm_page_free_zero(vm_page_t m)
1259 m->flags |= PG_ZERO;
1260 vm_page_free_toq(m);
1264 * Unbusy and handle the page queueing for a page from a getpages request that
1265 * was optionally read ahead or behind.
1268 vm_page_readahead_finish(vm_page_t m)
1271 /* We shouldn't put invalid pages on queues. */
1272 KASSERT(m->valid != 0, ("%s: %p is invalid", __func__, m));
1275 * Since the page is not the actually needed one, whether it should
1276 * be activated or deactivated is not obvious. Empirical results
1277 * have shown that deactivating the page is usually the best choice,
1278 * unless the page is wanted by another thread.
1281 if ((m->busy_lock & VPB_BIT_WAITERS) != 0)
1282 vm_page_activate(m);
1284 vm_page_deactivate(m);
1290 * vm_page_sleep_if_busy:
1292 * Sleep and release the page queues lock if the page is busied.
1293 * Returns TRUE if the thread slept.
1295 * The given page must be unlocked and object containing it must
1299 vm_page_sleep_if_busy(vm_page_t m, const char *msg)
1303 vm_page_lock_assert(m, MA_NOTOWNED);
1304 VM_OBJECT_ASSERT_WLOCKED(m->object);
1306 if (vm_page_busied(m)) {
1308 * The page-specific object must be cached because page
1309 * identity can change during the sleep, causing the
1310 * re-lock of a different object.
1311 * It is assumed that a reference to the object is already
1312 * held by the callers.
1316 VM_OBJECT_WUNLOCK(obj);
1317 vm_page_busy_sleep(m, msg, false);
1318 VM_OBJECT_WLOCK(obj);
1325 * vm_page_dirty_KBI: [ internal use only ]
1327 * Set all bits in the page's dirty field.
1329 * The object containing the specified page must be locked if the
1330 * call is made from the machine-independent layer.
1332 * See vm_page_clear_dirty_mask().
1334 * This function should only be called by vm_page_dirty().
1337 vm_page_dirty_KBI(vm_page_t m)
1340 /* Refer to this operation by its public name. */
1341 KASSERT(m->valid == VM_PAGE_BITS_ALL,
1342 ("vm_page_dirty: page is invalid!"));
1343 m->dirty = VM_PAGE_BITS_ALL;
1347 * vm_page_insert: [ internal use only ]
1349 * Inserts the given mem entry into the object and object list.
1351 * The object must be locked.
1354 vm_page_insert(vm_page_t m, vm_object_t object, vm_pindex_t pindex)
1358 VM_OBJECT_ASSERT_WLOCKED(object);
1359 mpred = vm_radix_lookup_le(&object->rtree, pindex);
1360 return (vm_page_insert_after(m, object, pindex, mpred));
1364 * vm_page_insert_after:
1366 * Inserts the page "m" into the specified object at offset "pindex".
1368 * The page "mpred" must immediately precede the offset "pindex" within
1369 * the specified object.
1371 * The object must be locked.
1374 vm_page_insert_after(vm_page_t m, vm_object_t object, vm_pindex_t pindex,
1379 VM_OBJECT_ASSERT_WLOCKED(object);
1380 KASSERT(m->object == NULL,
1381 ("vm_page_insert_after: page already inserted"));
1382 if (mpred != NULL) {
1383 KASSERT(mpred->object == object,
1384 ("vm_page_insert_after: object doesn't contain mpred"));
1385 KASSERT(mpred->pindex < pindex,
1386 ("vm_page_insert_after: mpred doesn't precede pindex"));
1387 msucc = TAILQ_NEXT(mpred, listq);
1389 msucc = TAILQ_FIRST(&object->memq);
1391 KASSERT(msucc->pindex > pindex,
1392 ("vm_page_insert_after: msucc doesn't succeed pindex"));
1395 * Record the object/offset pair in this page
1401 * Now link into the object's ordered list of backed pages.
1403 if (vm_radix_insert(&object->rtree, m)) {
1408 vm_page_insert_radixdone(m, object, mpred);
1413 * vm_page_insert_radixdone:
1415 * Complete page "m" insertion into the specified object after the
1416 * radix trie hooking.
1418 * The page "mpred" must precede the offset "m->pindex" within the
1421 * The object must be locked.
1424 vm_page_insert_radixdone(vm_page_t m, vm_object_t object, vm_page_t mpred)
1427 VM_OBJECT_ASSERT_WLOCKED(object);
1428 KASSERT(object != NULL && m->object == object,
1429 ("vm_page_insert_radixdone: page %p has inconsistent object", m));
1430 if (mpred != NULL) {
1431 KASSERT(mpred->object == object,
1432 ("vm_page_insert_after: object doesn't contain mpred"));
1433 KASSERT(mpred->pindex < m->pindex,
1434 ("vm_page_insert_after: mpred doesn't precede pindex"));
1438 TAILQ_INSERT_AFTER(&object->memq, mpred, m, listq);
1440 TAILQ_INSERT_HEAD(&object->memq, m, listq);
1443 * Show that the object has one more resident page.
1445 object->resident_page_count++;
1448 * Hold the vnode until the last page is released.
1450 if (object->resident_page_count == 1 && object->type == OBJT_VNODE)
1451 vhold(object->handle);
1454 * Since we are inserting a new and possibly dirty page,
1455 * update the object's OBJ_MIGHTBEDIRTY flag.
1457 if (pmap_page_is_write_mapped(m))
1458 vm_object_set_writeable_dirty(object);
1464 * Removes the specified page from its containing object, but does not
1465 * invalidate any backing storage. Return true if the page may be safely
1466 * freed and false otherwise.
1468 * The object must be locked. The page must be locked if it is managed.
1471 vm_page_remove(vm_page_t m)
1478 if ((m->oflags & VPO_UNMANAGED) == 0)
1479 vm_page_assert_locked(m);
1480 VM_OBJECT_ASSERT_WLOCKED(object);
1481 if (vm_page_xbusied(m))
1482 vm_page_xunbusy_maybelocked(m);
1483 mrem = vm_radix_remove(&object->rtree, m->pindex);
1484 KASSERT(mrem == m, ("removed page %p, expected page %p", mrem, m));
1487 * Now remove from the object's list of backed pages.
1489 TAILQ_REMOVE(&object->memq, m, listq);
1492 * And show that the object has one fewer resident page.
1494 object->resident_page_count--;
1497 * The vnode may now be recycled.
1499 if (object->resident_page_count == 0 && object->type == OBJT_VNODE)
1500 vdrop(object->handle);
1503 return (!vm_page_wired(m));
1509 * Returns the page associated with the object/offset
1510 * pair specified; if none is found, NULL is returned.
1512 * The object must be locked.
1515 vm_page_lookup(vm_object_t object, vm_pindex_t pindex)
1518 VM_OBJECT_ASSERT_LOCKED(object);
1519 return (vm_radix_lookup(&object->rtree, pindex));
1523 * vm_page_find_least:
1525 * Returns the page associated with the object with least pindex
1526 * greater than or equal to the parameter pindex, or NULL.
1528 * The object must be locked.
1531 vm_page_find_least(vm_object_t object, vm_pindex_t pindex)
1535 VM_OBJECT_ASSERT_LOCKED(object);
1536 if ((m = TAILQ_FIRST(&object->memq)) != NULL && m->pindex < pindex)
1537 m = vm_radix_lookup_ge(&object->rtree, pindex);
1542 * Returns the given page's successor (by pindex) within the object if it is
1543 * resident; if none is found, NULL is returned.
1545 * The object must be locked.
1548 vm_page_next(vm_page_t m)
1552 VM_OBJECT_ASSERT_LOCKED(m->object);
1553 if ((next = TAILQ_NEXT(m, listq)) != NULL) {
1554 MPASS(next->object == m->object);
1555 if (next->pindex != m->pindex + 1)
1562 * Returns the given page's predecessor (by pindex) within the object if it is
1563 * resident; if none is found, NULL is returned.
1565 * The object must be locked.
1568 vm_page_prev(vm_page_t m)
1572 VM_OBJECT_ASSERT_LOCKED(m->object);
1573 if ((prev = TAILQ_PREV(m, pglist, listq)) != NULL) {
1574 MPASS(prev->object == m->object);
1575 if (prev->pindex != m->pindex - 1)
1582 * Uses the page mnew as a replacement for an existing page at index
1583 * pindex which must be already present in the object.
1585 * The existing page must not be on a paging queue.
1588 vm_page_replace(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex)
1592 VM_OBJECT_ASSERT_WLOCKED(object);
1593 KASSERT(mnew->object == NULL,
1594 ("vm_page_replace: page %p already in object", mnew));
1595 KASSERT(mnew->queue == PQ_NONE,
1596 ("vm_page_replace: new page %p is on a paging queue", mnew));
1599 * This function mostly follows vm_page_insert() and
1600 * vm_page_remove() without the radix, object count and vnode
1601 * dance. Double check such functions for more comments.
1604 mnew->object = object;
1605 mnew->pindex = pindex;
1606 mold = vm_radix_replace(&object->rtree, mnew);
1607 KASSERT(mold->queue == PQ_NONE,
1608 ("vm_page_replace: old page %p is on a paging queue", mold));
1610 /* Keep the resident page list in sorted order. */
1611 TAILQ_INSERT_AFTER(&object->memq, mold, mnew, listq);
1612 TAILQ_REMOVE(&object->memq, mold, listq);
1614 mold->object = NULL;
1615 vm_page_xunbusy_maybelocked(mold);
1618 * The object's resident_page_count does not change because we have
1619 * swapped one page for another, but OBJ_MIGHTBEDIRTY.
1621 if (pmap_page_is_write_mapped(mnew))
1622 vm_object_set_writeable_dirty(object);
1629 * Move the given memory entry from its
1630 * current object to the specified target object/offset.
1632 * Note: swap associated with the page must be invalidated by the move. We
1633 * have to do this for several reasons: (1) we aren't freeing the
1634 * page, (2) we are dirtying the page, (3) the VM system is probably
1635 * moving the page from object A to B, and will then later move
1636 * the backing store from A to B and we can't have a conflict.
1638 * Note: we *always* dirty the page. It is necessary both for the
1639 * fact that we moved it, and because we may be invalidating
1642 * The objects must be locked.
1645 vm_page_rename(vm_page_t m, vm_object_t new_object, vm_pindex_t new_pindex)
1650 VM_OBJECT_ASSERT_WLOCKED(new_object);
1652 mpred = vm_radix_lookup_le(&new_object->rtree, new_pindex);
1653 KASSERT(mpred == NULL || mpred->pindex != new_pindex,
1654 ("vm_page_rename: pindex already renamed"));
1657 * Create a custom version of vm_page_insert() which does not depend
1658 * by m_prev and can cheat on the implementation aspects of the
1662 m->pindex = new_pindex;
1663 if (vm_radix_insert(&new_object->rtree, m)) {
1669 * The operation cannot fail anymore. The removal must happen before
1670 * the listq iterator is tainted.
1674 (void)vm_page_remove(m);
1676 /* Return back to the new pindex to complete vm_page_insert(). */
1677 m->pindex = new_pindex;
1678 m->object = new_object;
1680 vm_page_insert_radixdone(m, new_object, mpred);
1688 * Allocate and return a page that is associated with the specified
1689 * object and offset pair. By default, this page is exclusive busied.
1691 * The caller must always specify an allocation class.
1693 * allocation classes:
1694 * VM_ALLOC_NORMAL normal process request
1695 * VM_ALLOC_SYSTEM system *really* needs a page
1696 * VM_ALLOC_INTERRUPT interrupt time request
1698 * optional allocation flags:
1699 * VM_ALLOC_COUNT(number) the number of additional pages that the caller
1700 * intends to allocate
1701 * VM_ALLOC_NOBUSY do not exclusive busy the page
1702 * VM_ALLOC_NODUMP do not include the page in a kernel core dump
1703 * VM_ALLOC_NOOBJ page is not associated with an object and
1704 * should not be exclusive busy
1705 * VM_ALLOC_SBUSY shared busy the allocated page
1706 * VM_ALLOC_WIRED wire the allocated page
1707 * VM_ALLOC_ZERO prefer a zeroed page
1710 vm_page_alloc(vm_object_t object, vm_pindex_t pindex, int req)
1713 return (vm_page_alloc_after(object, pindex, req, object != NULL ?
1714 vm_radix_lookup_le(&object->rtree, pindex) : NULL));
1718 vm_page_alloc_domain(vm_object_t object, vm_pindex_t pindex, int domain,
1722 return (vm_page_alloc_domain_after(object, pindex, domain, req,
1723 object != NULL ? vm_radix_lookup_le(&object->rtree, pindex) :
1728 * Allocate a page in the specified object with the given page index. To
1729 * optimize insertion of the page into the object, the caller must also specifiy
1730 * the resident page in the object with largest index smaller than the given
1731 * page index, or NULL if no such page exists.
1734 vm_page_alloc_after(vm_object_t object, vm_pindex_t pindex,
1735 int req, vm_page_t mpred)
1737 struct vm_domainset_iter di;
1741 vm_domainset_iter_page_init(&di, object, pindex, &domain, &req);
1743 m = vm_page_alloc_domain_after(object, pindex, domain, req,
1747 } while (vm_domainset_iter_page(&di, object, &domain) == 0);
1753 * Returns true if the number of free pages exceeds the minimum
1754 * for the request class and false otherwise.
1757 vm_domain_allocate(struct vm_domain *vmd, int req, int npages)
1759 u_int limit, old, new;
1761 req = req & VM_ALLOC_CLASS_MASK;
1764 * The page daemon is allowed to dig deeper into the free page list.
1766 if (curproc == pageproc && req != VM_ALLOC_INTERRUPT)
1767 req = VM_ALLOC_SYSTEM;
1768 if (req == VM_ALLOC_INTERRUPT)
1770 else if (req == VM_ALLOC_SYSTEM)
1771 limit = vmd->vmd_interrupt_free_min;
1773 limit = vmd->vmd_free_reserved;
1776 * Attempt to reserve the pages. Fail if we're below the limit.
1779 old = vmd->vmd_free_count;
1784 } while (atomic_fcmpset_int(&vmd->vmd_free_count, &old, new) == 0);
1786 /* Wake the page daemon if we've crossed the threshold. */
1787 if (vm_paging_needed(vmd, new) && !vm_paging_needed(vmd, old))
1788 pagedaemon_wakeup(vmd->vmd_domain);
1790 /* Only update bitsets on transitions. */
1791 if ((old >= vmd->vmd_free_min && new < vmd->vmd_free_min) ||
1792 (old >= vmd->vmd_free_severe && new < vmd->vmd_free_severe))
1799 vm_page_alloc_domain_after(vm_object_t object, vm_pindex_t pindex, int domain,
1800 int req, vm_page_t mpred)
1802 struct vm_domain *vmd;
1806 KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) &&
1807 (object != NULL || (req & VM_ALLOC_SBUSY) == 0) &&
1808 ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) !=
1809 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)),
1810 ("inconsistent object(%p)/req(%x)", object, req));
1811 KASSERT(object == NULL || (req & VM_ALLOC_WAITOK) == 0,
1812 ("Can't sleep and retry object insertion."));
1813 KASSERT(mpred == NULL || mpred->pindex < pindex,
1814 ("mpred %p doesn't precede pindex 0x%jx", mpred,
1815 (uintmax_t)pindex));
1817 VM_OBJECT_ASSERT_WLOCKED(object);
1821 pool = object != NULL ? VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT;
1823 #if VM_NRESERVLEVEL > 0
1825 * Can we allocate the page from a reservation?
1827 if (vm_object_reserv(object) &&
1828 ((m = vm_reserv_extend(req, object, pindex, domain, mpred)) != NULL ||
1829 (m = vm_reserv_alloc_page(req, object, pindex, domain, mpred)) != NULL)) {
1830 domain = vm_phys_domain(m);
1831 vmd = VM_DOMAIN(domain);
1835 vmd = VM_DOMAIN(domain);
1836 if (vmd->vmd_pgcache[pool].zone != NULL) {
1837 m = uma_zalloc(vmd->vmd_pgcache[pool].zone, M_NOWAIT);
1839 flags |= PG_PCPU_CACHE;
1843 if (vm_domain_allocate(vmd, req, 1)) {
1845 * If not, allocate it from the free page queues.
1847 vm_domain_free_lock(vmd);
1848 m = vm_phys_alloc_pages(domain, pool, 0);
1849 vm_domain_free_unlock(vmd);
1851 vm_domain_freecnt_inc(vmd, 1);
1852 #if VM_NRESERVLEVEL > 0
1853 if (vm_reserv_reclaim_inactive(domain))
1860 * Not allocatable, give up.
1862 if (vm_domain_alloc_fail(vmd, object, req))
1868 * At this point we had better have found a good page.
1872 vm_page_alloc_check(m);
1875 * Initialize the page. Only the PG_ZERO flag is inherited.
1877 if ((req & VM_ALLOC_ZERO) != 0)
1878 flags |= (m->flags & PG_ZERO);
1879 if ((req & VM_ALLOC_NODUMP) != 0)
1883 m->oflags = object == NULL || (object->flags & OBJ_UNMANAGED) != 0 ?
1885 m->busy_lock = VPB_UNBUSIED;
1886 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ | VM_ALLOC_SBUSY)) == 0)
1887 m->busy_lock = VPB_SINGLE_EXCLUSIVER;
1888 if ((req & VM_ALLOC_SBUSY) != 0)
1889 m->busy_lock = VPB_SHARERS_WORD(1);
1890 if (req & VM_ALLOC_WIRED) {
1892 * The page lock is not required for wiring a page until that
1893 * page is inserted into the object.
1900 if (object != NULL) {
1901 if (vm_page_insert_after(m, object, pindex, mpred)) {
1902 if (req & VM_ALLOC_WIRED) {
1906 KASSERT(m->object == NULL, ("page %p has object", m));
1907 m->oflags = VPO_UNMANAGED;
1908 m->busy_lock = VPB_UNBUSIED;
1909 /* Don't change PG_ZERO. */
1910 vm_page_free_toq(m);
1911 if (req & VM_ALLOC_WAITFAIL) {
1912 VM_OBJECT_WUNLOCK(object);
1914 VM_OBJECT_WLOCK(object);
1919 /* Ignore device objects; the pager sets "memattr" for them. */
1920 if (object->memattr != VM_MEMATTR_DEFAULT &&
1921 (object->flags & OBJ_FICTITIOUS) == 0)
1922 pmap_page_set_memattr(m, object->memattr);
1930 * vm_page_alloc_contig:
1932 * Allocate a contiguous set of physical pages of the given size "npages"
1933 * from the free lists. All of the physical pages must be at or above
1934 * the given physical address "low" and below the given physical address
1935 * "high". The given value "alignment" determines the alignment of the
1936 * first physical page in the set. If the given value "boundary" is
1937 * non-zero, then the set of physical pages cannot cross any physical
1938 * address boundary that is a multiple of that value. Both "alignment"
1939 * and "boundary" must be a power of two.
1941 * If the specified memory attribute, "memattr", is VM_MEMATTR_DEFAULT,
1942 * then the memory attribute setting for the physical pages is configured
1943 * to the object's memory attribute setting. Otherwise, the memory
1944 * attribute setting for the physical pages is configured to "memattr",
1945 * overriding the object's memory attribute setting. However, if the
1946 * object's memory attribute setting is not VM_MEMATTR_DEFAULT, then the
1947 * memory attribute setting for the physical pages cannot be configured
1948 * to VM_MEMATTR_DEFAULT.
1950 * The specified object may not contain fictitious pages.
1952 * The caller must always specify an allocation class.
1954 * allocation classes:
1955 * VM_ALLOC_NORMAL normal process request
1956 * VM_ALLOC_SYSTEM system *really* needs a page
1957 * VM_ALLOC_INTERRUPT interrupt time request
1959 * optional allocation flags:
1960 * VM_ALLOC_NOBUSY do not exclusive busy the page
1961 * VM_ALLOC_NODUMP do not include the page in a kernel core dump
1962 * VM_ALLOC_NOOBJ page is not associated with an object and
1963 * should not be exclusive busy
1964 * VM_ALLOC_SBUSY shared busy the allocated page
1965 * VM_ALLOC_WIRED wire the allocated page
1966 * VM_ALLOC_ZERO prefer a zeroed page
1969 vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req,
1970 u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment,
1971 vm_paddr_t boundary, vm_memattr_t memattr)
1973 struct vm_domainset_iter di;
1977 vm_domainset_iter_page_init(&di, object, pindex, &domain, &req);
1979 m = vm_page_alloc_contig_domain(object, pindex, domain, req,
1980 npages, low, high, alignment, boundary, memattr);
1983 } while (vm_domainset_iter_page(&di, object, &domain) == 0);
1989 vm_page_alloc_contig_domain(vm_object_t object, vm_pindex_t pindex, int domain,
1990 int req, u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment,
1991 vm_paddr_t boundary, vm_memattr_t memattr)
1993 struct vm_domain *vmd;
1994 vm_page_t m, m_ret, mpred;
1995 u_int busy_lock, flags, oflags;
1997 mpred = NULL; /* XXX: pacify gcc */
1998 KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) &&
1999 (object != NULL || (req & VM_ALLOC_SBUSY) == 0) &&
2000 ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) !=
2001 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)),
2002 ("vm_page_alloc_contig: inconsistent object(%p)/req(%x)", object,
2004 KASSERT(object == NULL || (req & VM_ALLOC_WAITOK) == 0,
2005 ("Can't sleep and retry object insertion."));
2006 if (object != NULL) {
2007 VM_OBJECT_ASSERT_WLOCKED(object);
2008 KASSERT((object->flags & OBJ_FICTITIOUS) == 0,
2009 ("vm_page_alloc_contig: object %p has fictitious pages",
2012 KASSERT(npages > 0, ("vm_page_alloc_contig: npages is zero"));
2014 if (object != NULL) {
2015 mpred = vm_radix_lookup_le(&object->rtree, pindex);
2016 KASSERT(mpred == NULL || mpred->pindex != pindex,
2017 ("vm_page_alloc_contig: pindex already allocated"));
2021 * Can we allocate the pages without the number of free pages falling
2022 * below the lower bound for the allocation class?
2026 #if VM_NRESERVLEVEL > 0
2028 * Can we allocate the pages from a reservation?
2030 if (vm_object_reserv(object) &&
2031 ((m_ret = vm_reserv_extend_contig(req, object, pindex, domain,
2032 npages, low, high, alignment, boundary, mpred)) != NULL ||
2033 (m_ret = vm_reserv_alloc_contig(req, object, pindex, domain,
2034 npages, low, high, alignment, boundary, mpred)) != NULL)) {
2035 domain = vm_phys_domain(m_ret);
2036 vmd = VM_DOMAIN(domain);
2040 vmd = VM_DOMAIN(domain);
2041 if (vm_domain_allocate(vmd, req, npages)) {
2043 * allocate them from the free page queues.
2045 vm_domain_free_lock(vmd);
2046 m_ret = vm_phys_alloc_contig(domain, npages, low, high,
2047 alignment, boundary);
2048 vm_domain_free_unlock(vmd);
2049 if (m_ret == NULL) {
2050 vm_domain_freecnt_inc(vmd, npages);
2051 #if VM_NRESERVLEVEL > 0
2052 if (vm_reserv_reclaim_contig(domain, npages, low,
2053 high, alignment, boundary))
2058 if (m_ret == NULL) {
2059 if (vm_domain_alloc_fail(vmd, object, req))
2063 #if VM_NRESERVLEVEL > 0
2066 for (m = m_ret; m < &m_ret[npages]; m++) {
2068 vm_page_alloc_check(m);
2072 * Initialize the pages. Only the PG_ZERO flag is inherited.
2075 if ((req & VM_ALLOC_ZERO) != 0)
2077 if ((req & VM_ALLOC_NODUMP) != 0)
2079 oflags = object == NULL || (object->flags & OBJ_UNMANAGED) != 0 ?
2081 busy_lock = VPB_UNBUSIED;
2082 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ | VM_ALLOC_SBUSY)) == 0)
2083 busy_lock = VPB_SINGLE_EXCLUSIVER;
2084 if ((req & VM_ALLOC_SBUSY) != 0)
2085 busy_lock = VPB_SHARERS_WORD(1);
2086 if ((req & VM_ALLOC_WIRED) != 0)
2087 vm_wire_add(npages);
2088 if (object != NULL) {
2089 if (object->memattr != VM_MEMATTR_DEFAULT &&
2090 memattr == VM_MEMATTR_DEFAULT)
2091 memattr = object->memattr;
2093 for (m = m_ret; m < &m_ret[npages]; m++) {
2095 m->flags = (m->flags | PG_NODUMP) & flags;
2096 m->busy_lock = busy_lock;
2097 if ((req & VM_ALLOC_WIRED) != 0)
2101 if (object != NULL) {
2102 if (vm_page_insert_after(m, object, pindex, mpred)) {
2103 if ((req & VM_ALLOC_WIRED) != 0)
2104 vm_wire_sub(npages);
2105 KASSERT(m->object == NULL,
2106 ("page %p has object", m));
2108 for (m = m_ret; m < &m_ret[npages]; m++) {
2110 (req & VM_ALLOC_WIRED) != 0)
2112 m->oflags = VPO_UNMANAGED;
2113 m->busy_lock = VPB_UNBUSIED;
2114 /* Don't change PG_ZERO. */
2115 vm_page_free_toq(m);
2117 if (req & VM_ALLOC_WAITFAIL) {
2118 VM_OBJECT_WUNLOCK(object);
2120 VM_OBJECT_WLOCK(object);
2127 if (memattr != VM_MEMATTR_DEFAULT)
2128 pmap_page_set_memattr(m, memattr);
2135 * Check a page that has been freshly dequeued from a freelist.
2138 vm_page_alloc_check(vm_page_t m)
2141 KASSERT(m->object == NULL, ("page %p has object", m));
2142 KASSERT(m->queue == PQ_NONE && (m->aflags & PGA_QUEUE_STATE_MASK) == 0,
2143 ("page %p has unexpected queue %d, flags %#x",
2144 m, m->queue, (m->aflags & PGA_QUEUE_STATE_MASK)));
2145 KASSERT(!vm_page_held(m), ("page %p is held", m));
2146 KASSERT(!vm_page_busied(m), ("page %p is busy", m));
2147 KASSERT(m->dirty == 0, ("page %p is dirty", m));
2148 KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT,
2149 ("page %p has unexpected memattr %d",
2150 m, pmap_page_get_memattr(m)));
2151 KASSERT(m->valid == 0, ("free page %p is valid", m));
2155 * vm_page_alloc_freelist:
2157 * Allocate a physical page from the specified free page list.
2159 * The caller must always specify an allocation class.
2161 * allocation classes:
2162 * VM_ALLOC_NORMAL normal process request
2163 * VM_ALLOC_SYSTEM system *really* needs a page
2164 * VM_ALLOC_INTERRUPT interrupt time request
2166 * optional allocation flags:
2167 * VM_ALLOC_COUNT(number) the number of additional pages that the caller
2168 * intends to allocate
2169 * VM_ALLOC_WIRED wire the allocated page
2170 * VM_ALLOC_ZERO prefer a zeroed page
2173 vm_page_alloc_freelist(int freelist, int req)
2175 struct vm_domainset_iter di;
2179 vm_domainset_iter_page_init(&di, NULL, 0, &domain, &req);
2181 m = vm_page_alloc_freelist_domain(domain, freelist, req);
2184 } while (vm_domainset_iter_page(&di, NULL, &domain) == 0);
2190 vm_page_alloc_freelist_domain(int domain, int freelist, int req)
2192 struct vm_domain *vmd;
2197 vmd = VM_DOMAIN(domain);
2199 if (vm_domain_allocate(vmd, req, 1)) {
2200 vm_domain_free_lock(vmd);
2201 m = vm_phys_alloc_freelist_pages(domain, freelist,
2202 VM_FREEPOOL_DIRECT, 0);
2203 vm_domain_free_unlock(vmd);
2205 vm_domain_freecnt_inc(vmd, 1);
2208 if (vm_domain_alloc_fail(vmd, NULL, req))
2213 vm_page_alloc_check(m);
2216 * Initialize the page. Only the PG_ZERO flag is inherited.
2220 if ((req & VM_ALLOC_ZERO) != 0)
2223 if ((req & VM_ALLOC_WIRED) != 0) {
2225 * The page lock is not required for wiring a page that does
2226 * not belong to an object.
2231 /* Unmanaged pages don't use "act_count". */
2232 m->oflags = VPO_UNMANAGED;
2237 vm_page_zone_import(void *arg, void **store, int cnt, int domain, int flags)
2239 struct vm_domain *vmd;
2240 struct vm_pgcache *pgcache;
2244 vmd = VM_DOMAIN(pgcache->domain);
2245 /* Only import if we can bring in a full bucket. */
2246 if (cnt == 1 || !vm_domain_allocate(vmd, VM_ALLOC_NORMAL, cnt))
2248 domain = vmd->vmd_domain;
2249 vm_domain_free_lock(vmd);
2250 i = vm_phys_alloc_npages(domain, pgcache->pool, cnt,
2251 (vm_page_t *)store);
2252 vm_domain_free_unlock(vmd);
2254 vm_domain_freecnt_inc(vmd, cnt - i);
2260 vm_page_zone_release(void *arg, void **store, int cnt)
2262 struct vm_domain *vmd;
2263 struct vm_pgcache *pgcache;
2268 vmd = VM_DOMAIN(pgcache->domain);
2269 vm_domain_free_lock(vmd);
2270 for (i = 0; i < cnt; i++) {
2271 m = (vm_page_t)store[i];
2272 vm_phys_free_pages(m, 0);
2274 vm_domain_free_unlock(vmd);
2275 vm_domain_freecnt_inc(vmd, cnt);
2278 #define VPSC_ANY 0 /* No restrictions. */
2279 #define VPSC_NORESERV 1 /* Skip reservations; implies VPSC_NOSUPER. */
2280 #define VPSC_NOSUPER 2 /* Skip superpages. */
2283 * vm_page_scan_contig:
2285 * Scan vm_page_array[] between the specified entries "m_start" and
2286 * "m_end" for a run of contiguous physical pages that satisfy the
2287 * specified conditions, and return the lowest page in the run. The
2288 * specified "alignment" determines the alignment of the lowest physical
2289 * page in the run. If the specified "boundary" is non-zero, then the
2290 * run of physical pages cannot span a physical address that is a
2291 * multiple of "boundary".
2293 * "m_end" is never dereferenced, so it need not point to a vm_page
2294 * structure within vm_page_array[].
2296 * "npages" must be greater than zero. "m_start" and "m_end" must not
2297 * span a hole (or discontiguity) in the physical address space. Both
2298 * "alignment" and "boundary" must be a power of two.
2301 vm_page_scan_contig(u_long npages, vm_page_t m_start, vm_page_t m_end,
2302 u_long alignment, vm_paddr_t boundary, int options)
2308 #if VM_NRESERVLEVEL > 0
2311 int m_inc, order, run_ext, run_len;
2313 KASSERT(npages > 0, ("npages is 0"));
2314 KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
2315 KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
2319 for (m = m_start; m < m_end && run_len < npages; m += m_inc) {
2320 KASSERT((m->flags & PG_MARKER) == 0,
2321 ("page %p is PG_MARKER", m));
2322 KASSERT((m->flags & PG_FICTITIOUS) == 0 || m->wire_count == 1,
2323 ("fictitious page %p has invalid wire count", m));
2326 * If the current page would be the start of a run, check its
2327 * physical address against the end, alignment, and boundary
2328 * conditions. If it doesn't satisfy these conditions, either
2329 * terminate the scan or advance to the next page that
2330 * satisfies the failed condition.
2333 KASSERT(m_run == NULL, ("m_run != NULL"));
2334 if (m + npages > m_end)
2336 pa = VM_PAGE_TO_PHYS(m);
2337 if ((pa & (alignment - 1)) != 0) {
2338 m_inc = atop(roundup2(pa, alignment) - pa);
2341 if (rounddown2(pa ^ (pa + ptoa(npages) - 1),
2343 m_inc = atop(roundup2(pa, boundary) - pa);
2347 KASSERT(m_run != NULL, ("m_run == NULL"));
2349 vm_page_change_lock(m, &m_mtx);
2352 if (vm_page_held(m))
2354 #if VM_NRESERVLEVEL > 0
2355 else if ((level = vm_reserv_level(m)) >= 0 &&
2356 (options & VPSC_NORESERV) != 0) {
2358 /* Advance to the end of the reservation. */
2359 pa = VM_PAGE_TO_PHYS(m);
2360 m_inc = atop(roundup2(pa + 1, vm_reserv_size(level)) -
2364 else if ((object = m->object) != NULL) {
2366 * The page is considered eligible for relocation if
2367 * and only if it could be laundered or reclaimed by
2370 if (!VM_OBJECT_TRYRLOCK(object)) {
2372 VM_OBJECT_RLOCK(object);
2374 if (m->object != object) {
2376 * The page may have been freed.
2378 VM_OBJECT_RUNLOCK(object);
2380 } else if (vm_page_held(m)) {
2385 KASSERT((m->flags & PG_UNHOLDFREE) == 0,
2386 ("page %p is PG_UNHOLDFREE", m));
2387 /* Don't care: PG_NODUMP, PG_ZERO. */
2388 if (object->type != OBJT_DEFAULT &&
2389 object->type != OBJT_SWAP &&
2390 object->type != OBJT_VNODE) {
2392 #if VM_NRESERVLEVEL > 0
2393 } else if ((options & VPSC_NOSUPER) != 0 &&
2394 (level = vm_reserv_level_iffullpop(m)) >= 0) {
2396 /* Advance to the end of the superpage. */
2397 pa = VM_PAGE_TO_PHYS(m);
2398 m_inc = atop(roundup2(pa + 1,
2399 vm_reserv_size(level)) - pa);
2401 } else if (object->memattr == VM_MEMATTR_DEFAULT &&
2402 vm_page_queue(m) != PQ_NONE && !vm_page_busied(m)) {
2404 * The page is allocated but eligible for
2405 * relocation. Extend the current run by one
2408 KASSERT(pmap_page_get_memattr(m) ==
2410 ("page %p has an unexpected memattr", m));
2411 KASSERT((m->oflags & (VPO_SWAPINPROG |
2412 VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0,
2413 ("page %p has unexpected oflags", m));
2414 /* Don't care: VPO_NOSYNC. */
2419 VM_OBJECT_RUNLOCK(object);
2420 #if VM_NRESERVLEVEL > 0
2421 } else if (level >= 0) {
2423 * The page is reserved but not yet allocated. In
2424 * other words, it is still free. Extend the current
2429 } else if ((order = m->order) < VM_NFREEORDER) {
2431 * The page is enqueued in the physical memory
2432 * allocator's free page queues. Moreover, it is the
2433 * first page in a power-of-two-sized run of
2434 * contiguous free pages. Add these pages to the end
2435 * of the current run, and jump ahead.
2437 run_ext = 1 << order;
2441 * Skip the page for one of the following reasons: (1)
2442 * It is enqueued in the physical memory allocator's
2443 * free page queues. However, it is not the first
2444 * page in a run of contiguous free pages. (This case
2445 * rarely occurs because the scan is performed in
2446 * ascending order.) (2) It is not reserved, and it is
2447 * transitioning from free to allocated. (Conversely,
2448 * the transition from allocated to free for managed
2449 * pages is blocked by the page lock.) (3) It is
2450 * allocated but not contained by an object and not
2451 * wired, e.g., allocated by Xen's balloon driver.
2457 * Extend or reset the current run of pages.
2472 if (run_len >= npages)
2478 * vm_page_reclaim_run:
2480 * Try to relocate each of the allocated virtual pages within the
2481 * specified run of physical pages to a new physical address. Free the
2482 * physical pages underlying the relocated virtual pages. A virtual page
2483 * is relocatable if and only if it could be laundered or reclaimed by
2484 * the page daemon. Whenever possible, a virtual page is relocated to a
2485 * physical address above "high".
2487 * Returns 0 if every physical page within the run was already free or
2488 * just freed by a successful relocation. Otherwise, returns a non-zero
2489 * value indicating why the last attempt to relocate a virtual page was
2492 * "req_class" must be an allocation class.
2495 vm_page_reclaim_run(int req_class, int domain, u_long npages, vm_page_t m_run,
2498 struct vm_domain *vmd;
2500 struct spglist free;
2503 vm_page_t m, m_end, m_new;
2504 int error, order, req;
2506 KASSERT((req_class & VM_ALLOC_CLASS_MASK) == req_class,
2507 ("req_class is not an allocation class"));
2511 m_end = m_run + npages;
2513 for (; error == 0 && m < m_end; m++) {
2514 KASSERT((m->flags & (PG_FICTITIOUS | PG_MARKER)) == 0,
2515 ("page %p is PG_FICTITIOUS or PG_MARKER", m));
2518 * Avoid releasing and reacquiring the same page lock.
2520 vm_page_change_lock(m, &m_mtx);
2522 if (vm_page_held(m))
2524 else if ((object = m->object) != NULL) {
2526 * The page is relocated if and only if it could be
2527 * laundered or reclaimed by the page daemon.
2529 if (!VM_OBJECT_TRYWLOCK(object)) {
2531 VM_OBJECT_WLOCK(object);
2533 if (m->object != object) {
2535 * The page may have been freed.
2537 VM_OBJECT_WUNLOCK(object);
2539 } else if (vm_page_held(m)) {
2544 KASSERT((m->flags & PG_UNHOLDFREE) == 0,
2545 ("page %p is PG_UNHOLDFREE", m));
2546 /* Don't care: PG_NODUMP, PG_ZERO. */
2547 if (object->type != OBJT_DEFAULT &&
2548 object->type != OBJT_SWAP &&
2549 object->type != OBJT_VNODE)
2551 else if (object->memattr != VM_MEMATTR_DEFAULT)
2553 else if (vm_page_queue(m) != PQ_NONE &&
2554 !vm_page_busied(m)) {
2555 KASSERT(pmap_page_get_memattr(m) ==
2557 ("page %p has an unexpected memattr", m));
2558 KASSERT((m->oflags & (VPO_SWAPINPROG |
2559 VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0,
2560 ("page %p has unexpected oflags", m));
2561 /* Don't care: VPO_NOSYNC. */
2562 if (m->valid != 0) {
2564 * First, try to allocate a new page
2565 * that is above "high". Failing
2566 * that, try to allocate a new page
2567 * that is below "m_run". Allocate
2568 * the new page between the end of
2569 * "m_run" and "high" only as a last
2572 req = req_class | VM_ALLOC_NOOBJ;
2573 if ((m->flags & PG_NODUMP) != 0)
2574 req |= VM_ALLOC_NODUMP;
2575 if (trunc_page(high) !=
2576 ~(vm_paddr_t)PAGE_MASK) {
2577 m_new = vm_page_alloc_contig(
2582 VM_MEMATTR_DEFAULT);
2585 if (m_new == NULL) {
2586 pa = VM_PAGE_TO_PHYS(m_run);
2587 m_new = vm_page_alloc_contig(
2589 0, pa - 1, PAGE_SIZE, 0,
2590 VM_MEMATTR_DEFAULT);
2592 if (m_new == NULL) {
2594 m_new = vm_page_alloc_contig(
2596 pa, high, PAGE_SIZE, 0,
2597 VM_MEMATTR_DEFAULT);
2599 if (m_new == NULL) {
2603 KASSERT(!vm_page_wired(m_new),
2604 ("page %p is wired", m_new));
2607 * Replace "m" with the new page. For
2608 * vm_page_replace(), "m" must be busy
2609 * and dequeued. Finally, change "m"
2610 * as if vm_page_free() was called.
2612 if (object->ref_count != 0)
2614 m_new->aflags = m->aflags &
2615 ~PGA_QUEUE_STATE_MASK;
2616 KASSERT(m_new->oflags == VPO_UNMANAGED,
2617 ("page %p is managed", m_new));
2618 m_new->oflags = m->oflags & VPO_NOSYNC;
2619 pmap_copy_page(m, m_new);
2620 m_new->valid = m->valid;
2621 m_new->dirty = m->dirty;
2622 m->flags &= ~PG_ZERO;
2625 vm_page_replace_checked(m_new, object,
2627 if (vm_page_free_prep(m))
2628 SLIST_INSERT_HEAD(&free, m,
2632 * The new page must be deactivated
2633 * before the object is unlocked.
2635 vm_page_change_lock(m_new, &m_mtx);
2636 vm_page_deactivate(m_new);
2638 m->flags &= ~PG_ZERO;
2640 if (vm_page_free_prep(m))
2641 SLIST_INSERT_HEAD(&free, m,
2643 KASSERT(m->dirty == 0,
2644 ("page %p is dirty", m));
2649 VM_OBJECT_WUNLOCK(object);
2651 MPASS(vm_phys_domain(m) == domain);
2652 vmd = VM_DOMAIN(domain);
2653 vm_domain_free_lock(vmd);
2655 if (order < VM_NFREEORDER) {
2657 * The page is enqueued in the physical memory
2658 * allocator's free page queues. Moreover, it
2659 * is the first page in a power-of-two-sized
2660 * run of contiguous free pages. Jump ahead
2661 * to the last page within that run, and
2662 * continue from there.
2664 m += (1 << order) - 1;
2666 #if VM_NRESERVLEVEL > 0
2667 else if (vm_reserv_is_page_free(m))
2670 vm_domain_free_unlock(vmd);
2671 if (order == VM_NFREEORDER)
2677 if ((m = SLIST_FIRST(&free)) != NULL) {
2680 vmd = VM_DOMAIN(domain);
2682 vm_domain_free_lock(vmd);
2684 MPASS(vm_phys_domain(m) == domain);
2685 SLIST_REMOVE_HEAD(&free, plinks.s.ss);
2686 vm_phys_free_pages(m, 0);
2688 } while ((m = SLIST_FIRST(&free)) != NULL);
2689 vm_domain_free_unlock(vmd);
2690 vm_domain_freecnt_inc(vmd, cnt);
2697 CTASSERT(powerof2(NRUNS));
2699 #define RUN_INDEX(count) ((count) & (NRUNS - 1))
2701 #define MIN_RECLAIM 8
2704 * vm_page_reclaim_contig:
2706 * Reclaim allocated, contiguous physical memory satisfying the specified
2707 * conditions by relocating the virtual pages using that physical memory.
2708 * Returns true if reclamation is successful and false otherwise. Since
2709 * relocation requires the allocation of physical pages, reclamation may
2710 * fail due to a shortage of free pages. When reclamation fails, callers
2711 * are expected to perform vm_wait() before retrying a failed allocation
2712 * operation, e.g., vm_page_alloc_contig().
2714 * The caller must always specify an allocation class through "req".
2716 * allocation classes:
2717 * VM_ALLOC_NORMAL normal process request
2718 * VM_ALLOC_SYSTEM system *really* needs a page
2719 * VM_ALLOC_INTERRUPT interrupt time request
2721 * The optional allocation flags are ignored.
2723 * "npages" must be greater than zero. Both "alignment" and "boundary"
2724 * must be a power of two.
2727 vm_page_reclaim_contig_domain(int domain, int req, u_long npages,
2728 vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary)
2730 struct vm_domain *vmd;
2731 vm_paddr_t curr_low;
2732 vm_page_t m_run, m_runs[NRUNS];
2733 u_long count, reclaimed;
2734 int error, i, options, req_class;
2736 KASSERT(npages > 0, ("npages is 0"));
2737 KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
2738 KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
2739 req_class = req & VM_ALLOC_CLASS_MASK;
2742 * The page daemon is allowed to dig deeper into the free page list.
2744 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT)
2745 req_class = VM_ALLOC_SYSTEM;
2748 * Return if the number of free pages cannot satisfy the requested
2751 vmd = VM_DOMAIN(domain);
2752 count = vmd->vmd_free_count;
2753 if (count < npages + vmd->vmd_free_reserved || (count < npages +
2754 vmd->vmd_interrupt_free_min && req_class == VM_ALLOC_SYSTEM) ||
2755 (count < npages && req_class == VM_ALLOC_INTERRUPT))
2759 * Scan up to three times, relaxing the restrictions ("options") on
2760 * the reclamation of reservations and superpages each time.
2762 for (options = VPSC_NORESERV;;) {
2764 * Find the highest runs that satisfy the given constraints
2765 * and restrictions, and record them in "m_runs".
2770 m_run = vm_phys_scan_contig(domain, npages, curr_low,
2771 high, alignment, boundary, options);
2774 curr_low = VM_PAGE_TO_PHYS(m_run) + ptoa(npages);
2775 m_runs[RUN_INDEX(count)] = m_run;
2780 * Reclaim the highest runs in LIFO (descending) order until
2781 * the number of reclaimed pages, "reclaimed", is at least
2782 * MIN_RECLAIM. Reset "reclaimed" each time because each
2783 * reclamation is idempotent, and runs will (likely) recur
2784 * from one scan to the next as restrictions are relaxed.
2787 for (i = 0; count > 0 && i < NRUNS; i++) {
2789 m_run = m_runs[RUN_INDEX(count)];
2790 error = vm_page_reclaim_run(req_class, domain, npages,
2793 reclaimed += npages;
2794 if (reclaimed >= MIN_RECLAIM)
2800 * Either relax the restrictions on the next scan or return if
2801 * the last scan had no restrictions.
2803 if (options == VPSC_NORESERV)
2804 options = VPSC_NOSUPER;
2805 else if (options == VPSC_NOSUPER)
2807 else if (options == VPSC_ANY)
2808 return (reclaimed != 0);
2813 vm_page_reclaim_contig(int req, u_long npages, vm_paddr_t low, vm_paddr_t high,
2814 u_long alignment, vm_paddr_t boundary)
2816 struct vm_domainset_iter di;
2820 vm_domainset_iter_page_init(&di, NULL, 0, &domain, &req);
2822 ret = vm_page_reclaim_contig_domain(domain, req, npages, low,
2823 high, alignment, boundary);
2826 } while (vm_domainset_iter_page(&di, NULL, &domain) == 0);
2832 * Set the domain in the appropriate page level domainset.
2835 vm_domain_set(struct vm_domain *vmd)
2838 mtx_lock(&vm_domainset_lock);
2839 if (!vmd->vmd_minset && vm_paging_min(vmd)) {
2840 vmd->vmd_minset = 1;
2841 DOMAINSET_SET(vmd->vmd_domain, &vm_min_domains);
2843 if (!vmd->vmd_severeset && vm_paging_severe(vmd)) {
2844 vmd->vmd_severeset = 1;
2845 DOMAINSET_SET(vmd->vmd_domain, &vm_severe_domains);
2847 mtx_unlock(&vm_domainset_lock);
2851 * Clear the domain from the appropriate page level domainset.
2854 vm_domain_clear(struct vm_domain *vmd)
2857 mtx_lock(&vm_domainset_lock);
2858 if (vmd->vmd_minset && !vm_paging_min(vmd)) {
2859 vmd->vmd_minset = 0;
2860 DOMAINSET_CLR(vmd->vmd_domain, &vm_min_domains);
2861 if (vm_min_waiters != 0) {
2863 wakeup(&vm_min_domains);
2866 if (vmd->vmd_severeset && !vm_paging_severe(vmd)) {
2867 vmd->vmd_severeset = 0;
2868 DOMAINSET_CLR(vmd->vmd_domain, &vm_severe_domains);
2869 if (vm_severe_waiters != 0) {
2870 vm_severe_waiters = 0;
2871 wakeup(&vm_severe_domains);
2876 * If pageout daemon needs pages, then tell it that there are
2879 if (vmd->vmd_pageout_pages_needed &&
2880 vmd->vmd_free_count >= vmd->vmd_pageout_free_min) {
2881 wakeup(&vmd->vmd_pageout_pages_needed);
2882 vmd->vmd_pageout_pages_needed = 0;
2885 /* See comments in vm_wait_doms(). */
2886 if (vm_pageproc_waiters) {
2887 vm_pageproc_waiters = 0;
2888 wakeup(&vm_pageproc_waiters);
2890 mtx_unlock(&vm_domainset_lock);
2894 * Wait for free pages to exceed the min threshold globally.
2900 mtx_lock(&vm_domainset_lock);
2901 while (vm_page_count_min()) {
2903 msleep(&vm_min_domains, &vm_domainset_lock, PVM, "vmwait", 0);
2905 mtx_unlock(&vm_domainset_lock);
2909 * Wait for free pages to exceed the severe threshold globally.
2912 vm_wait_severe(void)
2915 mtx_lock(&vm_domainset_lock);
2916 while (vm_page_count_severe()) {
2917 vm_severe_waiters++;
2918 msleep(&vm_severe_domains, &vm_domainset_lock, PVM,
2921 mtx_unlock(&vm_domainset_lock);
2928 return (vm_severe_waiters + vm_min_waiters + vm_pageproc_waiters);
2932 vm_wait_doms(const domainset_t *wdoms)
2936 * We use racey wakeup synchronization to avoid expensive global
2937 * locking for the pageproc when sleeping with a non-specific vm_wait.
2938 * To handle this, we only sleep for one tick in this instance. It
2939 * is expected that most allocations for the pageproc will come from
2940 * kmem or vm_page_grab* which will use the more specific and
2941 * race-free vm_wait_domain().
2943 if (curproc == pageproc) {
2944 mtx_lock(&vm_domainset_lock);
2945 vm_pageproc_waiters++;
2946 msleep(&vm_pageproc_waiters, &vm_domainset_lock, PVM | PDROP,
2950 * XXX Ideally we would wait only until the allocation could
2951 * be satisfied. This condition can cause new allocators to
2952 * consume all freed pages while old allocators wait.
2954 mtx_lock(&vm_domainset_lock);
2955 if (vm_page_count_min_set(wdoms)) {
2957 msleep(&vm_min_domains, &vm_domainset_lock,
2958 PVM | PDROP, "vmwait", 0);
2960 mtx_unlock(&vm_domainset_lock);
2967 * Sleep until free pages are available for allocation.
2968 * - Called in various places after failed memory allocations.
2971 vm_wait_domain(int domain)
2973 struct vm_domain *vmd;
2976 vmd = VM_DOMAIN(domain);
2977 vm_domain_free_assert_unlocked(vmd);
2979 if (curproc == pageproc) {
2980 mtx_lock(&vm_domainset_lock);
2981 if (vmd->vmd_free_count < vmd->vmd_pageout_free_min) {
2982 vmd->vmd_pageout_pages_needed = 1;
2983 msleep(&vmd->vmd_pageout_pages_needed,
2984 &vm_domainset_lock, PDROP | PSWP, "VMWait", 0);
2986 mtx_unlock(&vm_domainset_lock);
2988 if (pageproc == NULL)
2989 panic("vm_wait in early boot");
2990 DOMAINSET_ZERO(&wdom);
2991 DOMAINSET_SET(vmd->vmd_domain, &wdom);
2992 vm_wait_doms(&wdom);
2999 * Sleep until free pages are available for allocation in the
3000 * affinity domains of the obj. If obj is NULL, the domain set
3001 * for the calling thread is used.
3002 * Called in various places after failed memory allocations.
3005 vm_wait(vm_object_t obj)
3007 struct domainset *d;
3012 * Carefully fetch pointers only once: the struct domainset
3013 * itself is ummutable but the pointer might change.
3016 d = obj->domain.dr_policy;
3018 d = curthread->td_domain.dr_policy;
3020 vm_wait_doms(&d->ds_mask);
3024 * vm_domain_alloc_fail:
3026 * Called when a page allocation function fails. Informs the
3027 * pagedaemon and performs the requested wait. Requires the
3028 * domain_free and object lock on entry. Returns with the
3029 * object lock held and free lock released. Returns an error when
3030 * retry is necessary.
3034 vm_domain_alloc_fail(struct vm_domain *vmd, vm_object_t object, int req)
3037 vm_domain_free_assert_unlocked(vmd);
3039 atomic_add_int(&vmd->vmd_pageout_deficit,
3040 max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1));
3041 if (req & (VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL)) {
3043 VM_OBJECT_WUNLOCK(object);
3044 vm_wait_domain(vmd->vmd_domain);
3046 VM_OBJECT_WLOCK(object);
3047 if (req & VM_ALLOC_WAITOK)
3057 * Sleep until free pages are available for allocation.
3058 * - Called only in vm_fault so that processes page faulting
3059 * can be easily tracked.
3060 * - Sleeps at a lower priority than vm_wait() so that vm_wait()ing
3061 * processes will be able to grab memory first. Do not change
3062 * this balance without careful testing first.
3065 vm_waitpfault(struct domainset *dset, int timo)
3069 * XXX Ideally we would wait only until the allocation could
3070 * be satisfied. This condition can cause new allocators to
3071 * consume all freed pages while old allocators wait.
3073 mtx_lock(&vm_domainset_lock);
3074 if (vm_page_count_min_set(&dset->ds_mask)) {
3076 msleep(&vm_min_domains, &vm_domainset_lock, PUSER | PDROP,
3079 mtx_unlock(&vm_domainset_lock);
3082 static struct vm_pagequeue *
3083 vm_page_pagequeue(vm_page_t m)
3088 if ((queue = atomic_load_8(&m->queue)) == PQ_NONE)
3090 return (&vm_pagequeue_domain(m)->vmd_pagequeues[queue]);
3094 vm_pqbatch_process_page(struct vm_pagequeue *pq, vm_page_t m)
3096 struct vm_domain *vmd;
3099 CRITICAL_ASSERT(curthread);
3100 vm_pagequeue_assert_locked(pq);
3103 * The page daemon is allowed to set m->queue = PQ_NONE without
3104 * the page queue lock held. In this case it is about to free the page,
3105 * which must not have any queue state.
3107 qflags = atomic_load_8(&m->aflags);
3108 KASSERT(pq == vm_page_pagequeue(m) ||
3109 (qflags & PGA_QUEUE_STATE_MASK) == 0,
3110 ("page %p doesn't belong to queue %p but has aflags %#x",
3113 if ((qflags & PGA_DEQUEUE) != 0) {
3114 if (__predict_true((qflags & PGA_ENQUEUED) != 0))
3115 vm_pagequeue_remove(pq, m);
3116 vm_page_dequeue_complete(m);
3117 } else if ((qflags & (PGA_REQUEUE | PGA_REQUEUE_HEAD)) != 0) {
3118 if ((qflags & PGA_ENQUEUED) != 0)
3119 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q);
3121 vm_pagequeue_cnt_inc(pq);
3122 vm_page_aflag_set(m, PGA_ENQUEUED);
3126 * Give PGA_REQUEUE_HEAD precedence over PGA_REQUEUE.
3127 * In particular, if both flags are set in close succession,
3128 * only PGA_REQUEUE_HEAD will be applied, even if it was set
3131 if ((qflags & PGA_REQUEUE_HEAD) != 0) {
3132 KASSERT(m->queue == PQ_INACTIVE,
3133 ("head enqueue not supported for page %p", m));
3134 vmd = vm_pagequeue_domain(m);
3135 TAILQ_INSERT_BEFORE(&vmd->vmd_inacthead, m, plinks.q);
3137 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q);
3139 vm_page_aflag_clear(m, qflags & (PGA_REQUEUE |
3145 vm_pqbatch_process(struct vm_pagequeue *pq, struct vm_batchqueue *bq,
3151 for (i = 0; i < bq->bq_cnt; i++) {
3153 if (__predict_false(m->queue != queue))
3155 vm_pqbatch_process_page(pq, m);
3157 vm_batchqueue_init(bq);
3161 vm_pqbatch_submit_page(vm_page_t m, uint8_t queue)
3163 struct vm_batchqueue *bq;
3164 struct vm_pagequeue *pq;
3167 vm_page_assert_locked(m);
3168 KASSERT(queue < PQ_COUNT, ("invalid queue %d", queue));
3170 domain = vm_phys_domain(m);
3171 pq = &vm_pagequeue_domain(m)->vmd_pagequeues[queue];
3174 bq = DPCPU_PTR(pqbatch[domain][queue]);
3175 if (vm_batchqueue_insert(bq, m)) {
3179 if (!vm_pagequeue_trylock(pq)) {
3181 vm_pagequeue_lock(pq);
3183 bq = DPCPU_PTR(pqbatch[domain][queue]);
3185 vm_pqbatch_process(pq, bq, queue);
3188 * The page may have been logically dequeued before we acquired the
3189 * page queue lock. In this case, the page lock prevents the page
3190 * from being logically enqueued elsewhere.
3192 if (__predict_true(m->queue == queue))
3193 vm_pqbatch_process_page(pq, m);
3195 KASSERT(m->queue == PQ_NONE,
3196 ("invalid queue transition for page %p", m));
3197 KASSERT((m->aflags & PGA_ENQUEUED) == 0,
3198 ("page %p is enqueued with invalid queue index", m));
3199 vm_page_aflag_clear(m, PGA_QUEUE_STATE_MASK);
3201 vm_pagequeue_unlock(pq);
3206 * vm_page_drain_pqbatch: [ internal use only ]
3208 * Force all per-CPU page queue batch queues to be drained. This is
3209 * intended for use in severe memory shortages, to ensure that pages
3210 * do not remain stuck in the batch queues.
3213 vm_page_drain_pqbatch(void)
3216 struct vm_domain *vmd;
3217 struct vm_pagequeue *pq;
3218 int cpu, domain, queue;
3223 sched_bind(td, cpu);
3226 for (domain = 0; domain < vm_ndomains; domain++) {
3227 vmd = VM_DOMAIN(domain);
3228 for (queue = 0; queue < PQ_COUNT; queue++) {
3229 pq = &vmd->vmd_pagequeues[queue];
3230 vm_pagequeue_lock(pq);
3232 vm_pqbatch_process(pq,
3233 DPCPU_PTR(pqbatch[domain][queue]), queue);
3235 vm_pagequeue_unlock(pq);
3245 * Complete the logical removal of a page from a page queue. We must be
3246 * careful to synchronize with the page daemon, which may be concurrently
3247 * examining the page with only the page lock held. The page must not be
3248 * in a state where it appears to be logically enqueued.
3251 vm_page_dequeue_complete(vm_page_t m)
3255 atomic_thread_fence_rel();
3256 vm_page_aflag_clear(m, PGA_QUEUE_STATE_MASK);
3260 * vm_page_dequeue_deferred: [ internal use only ]
3262 * Request removal of the given page from its current page
3263 * queue. Physical removal from the queue may be deferred
3266 * The page must be locked.
3269 vm_page_dequeue_deferred(vm_page_t m)
3273 vm_page_assert_locked(m);
3275 if ((queue = vm_page_queue(m)) == PQ_NONE)
3277 vm_page_aflag_set(m, PGA_DEQUEUE);
3278 vm_pqbatch_submit_page(m, queue);
3284 * Remove the page from whichever page queue it's in, if any.
3285 * The page must either be locked or unallocated. This constraint
3286 * ensures that the queue state of the page will remain consistent
3287 * after this function returns.
3290 vm_page_dequeue(vm_page_t m)
3292 struct vm_pagequeue *pq, *pq1;
3295 KASSERT(mtx_owned(vm_page_lockptr(m)) || m->object == NULL,
3296 ("page %p is allocated and unlocked", m));
3298 for (pq = vm_page_pagequeue(m);; pq = pq1) {
3301 * A thread may be concurrently executing
3302 * vm_page_dequeue_complete(). Ensure that all queue
3303 * state is cleared before we return.
3305 aflags = atomic_load_8(&m->aflags);
3306 if ((aflags & PGA_QUEUE_STATE_MASK) == 0)
3308 KASSERT((aflags & PGA_DEQUEUE) != 0,
3309 ("page %p has unexpected queue state flags %#x",
3313 * Busy wait until the thread updating queue state is
3314 * finished. Such a thread must be executing in a
3318 pq1 = vm_page_pagequeue(m);
3321 vm_pagequeue_lock(pq);
3322 if ((pq1 = vm_page_pagequeue(m)) == pq)
3324 vm_pagequeue_unlock(pq);
3326 KASSERT(pq == vm_page_pagequeue(m),
3327 ("%s: page %p migrated directly between queues", __func__, m));
3328 KASSERT((m->aflags & PGA_DEQUEUE) != 0 ||
3329 mtx_owned(vm_page_lockptr(m)),
3330 ("%s: queued unlocked page %p", __func__, m));
3332 if ((m->aflags & PGA_ENQUEUED) != 0)
3333 vm_pagequeue_remove(pq, m);
3334 vm_page_dequeue_complete(m);
3335 vm_pagequeue_unlock(pq);
3339 * Schedule the given page for insertion into the specified page queue.
3340 * Physical insertion of the page may be deferred indefinitely.
3343 vm_page_enqueue(vm_page_t m, uint8_t queue)
3346 vm_page_assert_locked(m);
3347 KASSERT(m->queue == PQ_NONE && (m->aflags & PGA_QUEUE_STATE_MASK) == 0,
3348 ("%s: page %p is already enqueued", __func__, m));
3351 if ((m->aflags & PGA_REQUEUE) == 0)
3352 vm_page_aflag_set(m, PGA_REQUEUE);
3353 vm_pqbatch_submit_page(m, queue);
3357 * vm_page_requeue: [ internal use only ]
3359 * Schedule a requeue of the given page.
3361 * The page must be locked.
3364 vm_page_requeue(vm_page_t m)
3367 vm_page_assert_locked(m);
3368 KASSERT(vm_page_queue(m) != PQ_NONE,
3369 ("%s: page %p is not logically enqueued", __func__, m));
3371 if ((m->aflags & PGA_REQUEUE) == 0)
3372 vm_page_aflag_set(m, PGA_REQUEUE);
3373 vm_pqbatch_submit_page(m, atomic_load_8(&m->queue));
3377 * vm_page_free_prep:
3379 * Prepares the given page to be put on the free list,
3380 * disassociating it from any VM object. The caller may return
3381 * the page to the free list only if this function returns true.
3383 * The object must be locked. The page must be locked if it is
3387 vm_page_free_prep(vm_page_t m)
3390 #if defined(DIAGNOSTIC) && defined(PHYS_TO_DMAP)
3391 if (PMAP_HAS_DMAP && (m->flags & PG_ZERO) != 0) {
3394 p = (uint64_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m));
3395 for (i = 0; i < PAGE_SIZE / sizeof(uint64_t); i++, p++)
3396 KASSERT(*p == 0, ("vm_page_free_prep %p PG_ZERO %d %jx",
3397 m, i, (uintmax_t)*p));
3400 if ((m->oflags & VPO_UNMANAGED) == 0) {
3401 vm_page_lock_assert(m, MA_OWNED);
3402 KASSERT(!pmap_page_is_mapped(m),
3403 ("vm_page_free_prep: freeing mapped page %p", m));
3405 KASSERT(m->queue == PQ_NONE,
3406 ("vm_page_free_prep: unmanaged page %p is queued", m));
3407 VM_CNT_INC(v_tfree);
3409 if (vm_page_sbusied(m))
3410 panic("vm_page_free_prep: freeing busy page %p", m);
3412 if (m->object != NULL)
3413 (void)vm_page_remove(m);
3416 * If fictitious remove object association and
3419 if ((m->flags & PG_FICTITIOUS) != 0) {
3420 KASSERT(m->wire_count == 1,
3421 ("fictitious page %p is not wired", m));
3422 KASSERT(m->queue == PQ_NONE,
3423 ("fictitious page %p is queued", m));
3428 * Pages need not be dequeued before they are returned to the physical
3429 * memory allocator, but they must at least be marked for a deferred
3432 if ((m->oflags & VPO_UNMANAGED) == 0)
3433 vm_page_dequeue_deferred(m);
3438 if (vm_page_wired(m) != 0)
3439 panic("vm_page_free_prep: freeing wired page %p", m);
3440 if (m->hold_count != 0) {
3441 m->flags &= ~PG_ZERO;
3442 KASSERT((m->flags & PG_UNHOLDFREE) == 0,
3443 ("vm_page_free_prep: freeing PG_UNHOLDFREE page %p", m));
3444 m->flags |= PG_UNHOLDFREE;
3449 * Restore the default memory attribute to the page.
3451 if (pmap_page_get_memattr(m) != VM_MEMATTR_DEFAULT)
3452 pmap_page_set_memattr(m, VM_MEMATTR_DEFAULT);
3454 #if VM_NRESERVLEVEL > 0
3456 * Determine whether the page belongs to a reservation. If the page was
3457 * allocated from a per-CPU cache, it cannot belong to a reservation, so
3458 * as an optimization, we avoid the check in that case.
3460 if ((m->flags & PG_PCPU_CACHE) == 0 && vm_reserv_free_page(m))
3470 * Returns the given page to the free list, disassociating it
3471 * from any VM object.
3473 * The object must be locked. The page must be locked if it is
3477 vm_page_free_toq(vm_page_t m)
3479 struct vm_domain *vmd;
3482 if (!vm_page_free_prep(m))
3485 vmd = vm_pagequeue_domain(m);
3486 zone = vmd->vmd_pgcache[m->pool].zone;
3487 if ((m->flags & PG_PCPU_CACHE) != 0 && zone != NULL) {
3491 vm_domain_free_lock(vmd);
3492 vm_phys_free_pages(m, 0);
3493 vm_domain_free_unlock(vmd);
3494 vm_domain_freecnt_inc(vmd, 1);
3498 * vm_page_free_pages_toq:
3500 * Returns a list of pages to the free list, disassociating it
3501 * from any VM object. In other words, this is equivalent to
3502 * calling vm_page_free_toq() for each page of a list of VM objects.
3504 * The objects must be locked. The pages must be locked if it is
3508 vm_page_free_pages_toq(struct spglist *free, bool update_wire_count)
3513 if (SLIST_EMPTY(free))
3517 while ((m = SLIST_FIRST(free)) != NULL) {
3519 SLIST_REMOVE_HEAD(free, plinks.s.ss);
3520 vm_page_free_toq(m);
3523 if (update_wire_count)
3530 * Mark this page as wired down. If the page is fictitious, then
3531 * its wire count must remain one.
3533 * The page must be locked.
3536 vm_page_wire(vm_page_t m)
3539 vm_page_assert_locked(m);
3540 if ((m->flags & PG_FICTITIOUS) != 0) {
3541 KASSERT(m->wire_count == 1,
3542 ("vm_page_wire: fictitious page %p's wire count isn't one",
3546 if (!vm_page_wired(m)) {
3547 KASSERT((m->oflags & VPO_UNMANAGED) == 0 ||
3548 m->queue == PQ_NONE,
3549 ("vm_page_wire: unmanaged page %p is queued", m));
3553 KASSERT(m->wire_count != 0, ("vm_page_wire: wire_count overflow m=%p", m));
3559 * Release one wiring of the specified page, potentially allowing it to be
3560 * paged out. Returns TRUE if the number of wirings transitions to zero and
3563 * Only managed pages belonging to an object can be paged out. If the number
3564 * of wirings transitions to zero and the page is eligible for page out, then
3565 * the page is added to the specified paging queue (unless PQ_NONE is
3566 * specified, in which case the page is dequeued if it belongs to a paging
3569 * If a page is fictitious, then its wire count must always be one.
3571 * A managed page must be locked.
3574 vm_page_unwire(vm_page_t m, uint8_t queue)
3578 KASSERT(queue < PQ_COUNT || queue == PQ_NONE,
3579 ("vm_page_unwire: invalid queue %u request for page %p",
3581 if ((m->oflags & VPO_UNMANAGED) == 0)
3582 vm_page_assert_locked(m);
3584 unwired = vm_page_unwire_noq(m);
3585 if (!unwired || (m->oflags & VPO_UNMANAGED) != 0 || m->object == NULL)
3588 if (vm_page_queue(m) == queue) {
3589 if (queue == PQ_ACTIVE)
3590 vm_page_reference(m);
3591 else if (queue != PQ_NONE)
3595 if (queue != PQ_NONE) {
3596 vm_page_enqueue(m, queue);
3597 if (queue == PQ_ACTIVE)
3598 /* Initialize act_count. */
3599 vm_page_activate(m);
3607 * vm_page_unwire_noq:
3609 * Unwire a page without (re-)inserting it into a page queue. It is up
3610 * to the caller to enqueue, requeue, or free the page as appropriate.
3611 * In most cases, vm_page_unwire() should be used instead.
3614 vm_page_unwire_noq(vm_page_t m)
3617 if ((m->oflags & VPO_UNMANAGED) == 0)
3618 vm_page_assert_locked(m);
3619 if ((m->flags & PG_FICTITIOUS) != 0) {
3620 KASSERT(m->wire_count == 1,
3621 ("vm_page_unwire: fictitious page %p's wire count isn't one", m));
3624 if (!vm_page_wired(m))
3625 panic("vm_page_unwire: page %p's wire count is zero", m);
3627 if (m->wire_count == 0) {
3637 * Put the specified page on the active list (if appropriate).
3638 * Ensure that act_count is at least ACT_INIT but do not otherwise
3641 * The page must be locked.
3644 vm_page_activate(vm_page_t m)
3647 vm_page_assert_locked(m);
3649 if (vm_page_wired(m) || (m->oflags & VPO_UNMANAGED) != 0)
3651 if (vm_page_queue(m) == PQ_ACTIVE) {
3652 if (m->act_count < ACT_INIT)
3653 m->act_count = ACT_INIT;
3658 if (m->act_count < ACT_INIT)
3659 m->act_count = ACT_INIT;
3660 vm_page_enqueue(m, PQ_ACTIVE);
3664 * Move the specified page to the tail of the inactive queue, or requeue
3665 * the page if it is already in the inactive queue.
3667 * The page must be locked.
3670 vm_page_deactivate(vm_page_t m)
3673 vm_page_assert_locked(m);
3675 if (vm_page_wired(m) || (m->oflags & VPO_UNMANAGED) != 0)
3678 if (!vm_page_inactive(m)) {
3680 vm_page_enqueue(m, PQ_INACTIVE);
3686 * Move the specified page close to the head of the inactive queue,
3687 * bypassing LRU. A marker page is used to maintain FIFO ordering.
3688 * As with regular enqueues, we use a per-CPU batch queue to reduce
3689 * contention on the page queue lock.
3691 * The page must be locked.
3694 vm_page_deactivate_noreuse(vm_page_t m)
3697 vm_page_assert_locked(m);
3699 if (vm_page_wired(m) || (m->oflags & VPO_UNMANAGED) != 0)
3702 if (!vm_page_inactive(m)) {
3704 m->queue = PQ_INACTIVE;
3706 if ((m->aflags & PGA_REQUEUE_HEAD) == 0)
3707 vm_page_aflag_set(m, PGA_REQUEUE_HEAD);
3708 vm_pqbatch_submit_page(m, PQ_INACTIVE);
3714 * Put a page in the laundry, or requeue it if it is already there.
3717 vm_page_launder(vm_page_t m)
3720 vm_page_assert_locked(m);
3721 if (vm_page_wired(m) || (m->oflags & VPO_UNMANAGED) != 0)
3724 if (vm_page_in_laundry(m))
3728 vm_page_enqueue(m, PQ_LAUNDRY);
3733 * vm_page_unswappable
3735 * Put a page in the PQ_UNSWAPPABLE holding queue.
3738 vm_page_unswappable(vm_page_t m)
3741 vm_page_assert_locked(m);
3742 KASSERT(!vm_page_wired(m) && (m->oflags & VPO_UNMANAGED) == 0,
3743 ("page %p already unswappable", m));
3746 vm_page_enqueue(m, PQ_UNSWAPPABLE);
3750 vm_page_release_toq(vm_page_t m, int flags)
3754 * Use a check of the valid bits to determine whether we should
3755 * accelerate reclamation of the page. The object lock might not be
3756 * held here, in which case the check is racy. At worst we will either
3757 * accelerate reclamation of a valid page and violate LRU, or
3758 * unnecessarily defer reclamation of an invalid page.
3760 * If we were asked to not cache the page, place it near the head of the
3761 * inactive queue so that is reclaimed sooner.
3763 if ((flags & (VPR_TRYFREE | VPR_NOREUSE)) != 0 || m->valid == 0)
3764 vm_page_deactivate_noreuse(m);
3765 else if (vm_page_active(m))
3766 vm_page_reference(m);
3768 vm_page_deactivate(m);
3772 * Unwire a page and either attempt to free it or re-add it to the page queues.
3775 vm_page_release(vm_page_t m, int flags)
3780 KASSERT((m->oflags & VPO_UNMANAGED) == 0,
3781 ("vm_page_release: page %p is unmanaged", m));
3784 if (m->object != NULL)
3785 VM_OBJECT_ASSERT_UNLOCKED(m->object);
3786 if (vm_page_unwire_noq(m)) {
3787 if ((object = m->object) == NULL) {
3791 if ((flags & VPR_TRYFREE) != 0 && !vm_page_busied(m) &&
3792 /* Depends on type stability. */
3793 VM_OBJECT_TRYWLOCK(object)) {
3795 * Only free unmapped pages. The busy test from
3796 * before the object was locked cannot be relied
3799 if ((object->ref_count == 0 ||
3800 !pmap_page_is_mapped(m)) && m->dirty == 0 &&
3801 !vm_page_busied(m)) {
3805 VM_OBJECT_WUNLOCK(object);
3809 vm_page_release_toq(m, flags);
3815 /* See vm_page_release(). */
3817 vm_page_release_locked(vm_page_t m, int flags)
3820 VM_OBJECT_ASSERT_WLOCKED(m->object);
3821 KASSERT((m->oflags & VPO_UNMANAGED) == 0,
3822 ("vm_page_release_locked: page %p is unmanaged", m));
3825 if (vm_page_unwire_noq(m)) {
3826 if ((flags & VPR_TRYFREE) != 0 &&
3827 (m->object->ref_count == 0 || !pmap_page_is_mapped(m)) &&
3828 m->dirty == 0 && !vm_page_busied(m)) {
3831 vm_page_release_toq(m, flags);
3840 * Apply the specified advice to the given page.
3842 * The object and page must be locked.
3845 vm_page_advise(vm_page_t m, int advice)
3848 vm_page_assert_locked(m);
3849 VM_OBJECT_ASSERT_WLOCKED(m->object);
3850 if (advice == MADV_FREE)
3852 * Mark the page clean. This will allow the page to be freed
3853 * without first paging it out. MADV_FREE pages are often
3854 * quickly reused by malloc(3), so we do not do anything that
3855 * would result in a page fault on a later access.
3858 else if (advice != MADV_DONTNEED) {
3859 if (advice == MADV_WILLNEED)
3860 vm_page_activate(m);
3865 * Clear any references to the page. Otherwise, the page daemon will
3866 * immediately reactivate the page.
3868 vm_page_aflag_clear(m, PGA_REFERENCED);
3870 if (advice != MADV_FREE && m->dirty == 0 && pmap_is_modified(m))
3874 * Place clean pages near the head of the inactive queue rather than
3875 * the tail, thus defeating the queue's LRU operation and ensuring that
3876 * the page will be reused quickly. Dirty pages not already in the
3877 * laundry are moved there.
3880 vm_page_deactivate_noreuse(m);
3881 else if (!vm_page_in_laundry(m))
3886 * Grab a page, waiting until we are waken up due to the page
3887 * changing state. We keep on waiting, if the page continues
3888 * to be in the object. If the page doesn't exist, first allocate it
3889 * and then conditionally zero it.
3891 * This routine may sleep.
3893 * The object must be locked on entry. The lock will, however, be released
3894 * and reacquired if the routine sleeps.
3897 vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags)
3903 VM_OBJECT_ASSERT_WLOCKED(object);
3904 KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 ||
3905 (allocflags & VM_ALLOC_IGN_SBUSY) != 0,
3906 ("vm_page_grab: VM_ALLOC_SBUSY/VM_ALLOC_IGN_SBUSY mismatch"));
3907 pflags = allocflags &
3908 ~(VM_ALLOC_NOWAIT | VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL);
3909 if ((allocflags & VM_ALLOC_NOWAIT) == 0)
3910 pflags |= VM_ALLOC_WAITFAIL;
3912 if ((m = vm_page_lookup(object, pindex)) != NULL) {
3913 sleep = (allocflags & VM_ALLOC_IGN_SBUSY) != 0 ?
3914 vm_page_xbusied(m) : vm_page_busied(m);
3916 if ((allocflags & VM_ALLOC_NOWAIT) != 0)
3919 * Reference the page before unlocking and
3920 * sleeping so that the page daemon is less
3921 * likely to reclaim it.
3923 vm_page_aflag_set(m, PGA_REFERENCED);
3925 VM_OBJECT_WUNLOCK(object);
3926 vm_page_busy_sleep(m, "pgrbwt", (allocflags &
3927 VM_ALLOC_IGN_SBUSY) != 0);
3928 VM_OBJECT_WLOCK(object);
3931 if ((allocflags & VM_ALLOC_WIRED) != 0) {
3937 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) == 0)
3939 if ((allocflags & VM_ALLOC_SBUSY) != 0)
3944 m = vm_page_alloc(object, pindex, pflags);
3946 if ((allocflags & VM_ALLOC_NOWAIT) != 0)
3950 if (allocflags & VM_ALLOC_ZERO && (m->flags & PG_ZERO) == 0)
3956 * Return the specified range of pages from the given object. For each
3957 * page offset within the range, if a page already exists within the object
3958 * at that offset and it is busy, then wait for it to change state. If,
3959 * instead, the page doesn't exist, then allocate it.
3961 * The caller must always specify an allocation class.
3963 * allocation classes:
3964 * VM_ALLOC_NORMAL normal process request
3965 * VM_ALLOC_SYSTEM system *really* needs the pages
3967 * The caller must always specify that the pages are to be busied and/or
3970 * optional allocation flags:
3971 * VM_ALLOC_IGN_SBUSY do not sleep on soft busy pages
3972 * VM_ALLOC_NOBUSY do not exclusive busy the page
3973 * VM_ALLOC_NOWAIT do not sleep
3974 * VM_ALLOC_SBUSY set page to sbusy state
3975 * VM_ALLOC_WIRED wire the pages
3976 * VM_ALLOC_ZERO zero and validate any invalid pages
3978 * If VM_ALLOC_NOWAIT is not specified, this routine may sleep. Otherwise, it
3979 * may return a partial prefix of the requested range.
3982 vm_page_grab_pages(vm_object_t object, vm_pindex_t pindex, int allocflags,
3983 vm_page_t *ma, int count)
3990 VM_OBJECT_ASSERT_WLOCKED(object);
3991 KASSERT(((u_int)allocflags >> VM_ALLOC_COUNT_SHIFT) == 0,
3992 ("vm_page_grap_pages: VM_ALLOC_COUNT() is not allowed"));
3993 KASSERT((allocflags & VM_ALLOC_NOBUSY) == 0 ||
3994 (allocflags & VM_ALLOC_WIRED) != 0,
3995 ("vm_page_grab_pages: the pages must be busied or wired"));
3996 KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 ||
3997 (allocflags & VM_ALLOC_IGN_SBUSY) != 0,
3998 ("vm_page_grab_pages: VM_ALLOC_SBUSY/IGN_SBUSY mismatch"));
4001 pflags = allocflags & ~(VM_ALLOC_NOWAIT | VM_ALLOC_WAITOK |
4002 VM_ALLOC_WAITFAIL | VM_ALLOC_IGN_SBUSY);
4003 if ((allocflags & VM_ALLOC_NOWAIT) == 0)
4004 pflags |= VM_ALLOC_WAITFAIL;
4007 m = vm_radix_lookup_le(&object->rtree, pindex + i);
4008 if (m == NULL || m->pindex != pindex + i) {
4012 mpred = TAILQ_PREV(m, pglist, listq);
4013 for (; i < count; i++) {
4015 sleep = (allocflags & VM_ALLOC_IGN_SBUSY) != 0 ?
4016 vm_page_xbusied(m) : vm_page_busied(m);
4018 if ((allocflags & VM_ALLOC_NOWAIT) != 0)
4021 * Reference the page before unlocking and
4022 * sleeping so that the page daemon is less
4023 * likely to reclaim it.
4025 vm_page_aflag_set(m, PGA_REFERENCED);
4027 VM_OBJECT_WUNLOCK(object);
4028 vm_page_busy_sleep(m, "grbmaw", (allocflags &
4029 VM_ALLOC_IGN_SBUSY) != 0);
4030 VM_OBJECT_WLOCK(object);
4033 if ((allocflags & VM_ALLOC_WIRED) != 0) {
4038 if ((allocflags & (VM_ALLOC_NOBUSY |
4039 VM_ALLOC_SBUSY)) == 0)
4041 if ((allocflags & VM_ALLOC_SBUSY) != 0)
4044 m = vm_page_alloc_after(object, pindex + i,
4045 pflags | VM_ALLOC_COUNT(count - i), mpred);
4047 if ((allocflags & VM_ALLOC_NOWAIT) != 0)
4052 if (m->valid == 0 && (allocflags & VM_ALLOC_ZERO) != 0) {
4053 if ((m->flags & PG_ZERO) == 0)
4055 m->valid = VM_PAGE_BITS_ALL;
4058 m = vm_page_next(m);
4064 * Mapping function for valid or dirty bits in a page.
4066 * Inputs are required to range within a page.
4069 vm_page_bits(int base, int size)
4075 base + size <= PAGE_SIZE,
4076 ("vm_page_bits: illegal base/size %d/%d", base, size)
4079 if (size == 0) /* handle degenerate case */
4082 first_bit = base >> DEV_BSHIFT;
4083 last_bit = (base + size - 1) >> DEV_BSHIFT;
4085 return (((vm_page_bits_t)2 << last_bit) -
4086 ((vm_page_bits_t)1 << first_bit));
4090 * vm_page_set_valid_range:
4092 * Sets portions of a page valid. The arguments are expected
4093 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive
4094 * of any partial chunks touched by the range. The invalid portion of
4095 * such chunks will be zeroed.
4097 * (base + size) must be less then or equal to PAGE_SIZE.
4100 vm_page_set_valid_range(vm_page_t m, int base, int size)
4104 VM_OBJECT_ASSERT_WLOCKED(m->object);
4105 if (size == 0) /* handle degenerate case */
4109 * If the base is not DEV_BSIZE aligned and the valid
4110 * bit is clear, we have to zero out a portion of the
4113 if ((frag = rounddown2(base, DEV_BSIZE)) != base &&
4114 (m->valid & (1 << (base >> DEV_BSHIFT))) == 0)
4115 pmap_zero_page_area(m, frag, base - frag);
4118 * If the ending offset is not DEV_BSIZE aligned and the
4119 * valid bit is clear, we have to zero out a portion of
4122 endoff = base + size;
4123 if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff &&
4124 (m->valid & (1 << (endoff >> DEV_BSHIFT))) == 0)
4125 pmap_zero_page_area(m, endoff,
4126 DEV_BSIZE - (endoff & (DEV_BSIZE - 1)));
4129 * Assert that no previously invalid block that is now being validated
4132 KASSERT((~m->valid & vm_page_bits(base, size) & m->dirty) == 0,
4133 ("vm_page_set_valid_range: page %p is dirty", m));
4136 * Set valid bits inclusive of any overlap.
4138 m->valid |= vm_page_bits(base, size);
4142 * Clear the given bits from the specified page's dirty field.
4144 static __inline void
4145 vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits)
4148 #if PAGE_SIZE < 16384
4153 * If the object is locked and the page is neither exclusive busy nor
4154 * write mapped, then the page's dirty field cannot possibly be
4155 * set by a concurrent pmap operation.
4157 VM_OBJECT_ASSERT_WLOCKED(m->object);
4158 if (!vm_page_xbusied(m) && !pmap_page_is_write_mapped(m))
4159 m->dirty &= ~pagebits;
4162 * The pmap layer can call vm_page_dirty() without
4163 * holding a distinguished lock. The combination of
4164 * the object's lock and an atomic operation suffice
4165 * to guarantee consistency of the page dirty field.
4167 * For PAGE_SIZE == 32768 case, compiler already
4168 * properly aligns the dirty field, so no forcible
4169 * alignment is needed. Only require existence of
4170 * atomic_clear_64 when page size is 32768.
4172 addr = (uintptr_t)&m->dirty;
4173 #if PAGE_SIZE == 32768
4174 atomic_clear_64((uint64_t *)addr, pagebits);
4175 #elif PAGE_SIZE == 16384
4176 atomic_clear_32((uint32_t *)addr, pagebits);
4177 #else /* PAGE_SIZE <= 8192 */
4179 * Use a trick to perform a 32-bit atomic on the
4180 * containing aligned word, to not depend on the existence
4181 * of atomic_clear_{8, 16}.
4183 shift = addr & (sizeof(uint32_t) - 1);
4184 #if BYTE_ORDER == BIG_ENDIAN
4185 shift = (sizeof(uint32_t) - sizeof(m->dirty) - shift) * NBBY;
4189 addr &= ~(sizeof(uint32_t) - 1);
4190 atomic_clear_32((uint32_t *)addr, pagebits << shift);
4191 #endif /* PAGE_SIZE */
4196 * vm_page_set_validclean:
4198 * Sets portions of a page valid and clean. The arguments are expected
4199 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive
4200 * of any partial chunks touched by the range. The invalid portion of
4201 * such chunks will be zero'd.
4203 * (base + size) must be less then or equal to PAGE_SIZE.
4206 vm_page_set_validclean(vm_page_t m, int base, int size)
4208 vm_page_bits_t oldvalid, pagebits;
4211 VM_OBJECT_ASSERT_WLOCKED(m->object);
4212 if (size == 0) /* handle degenerate case */
4216 * If the base is not DEV_BSIZE aligned and the valid
4217 * bit is clear, we have to zero out a portion of the
4220 if ((frag = rounddown2(base, DEV_BSIZE)) != base &&
4221 (m->valid & ((vm_page_bits_t)1 << (base >> DEV_BSHIFT))) == 0)
4222 pmap_zero_page_area(m, frag, base - frag);
4225 * If the ending offset is not DEV_BSIZE aligned and the
4226 * valid bit is clear, we have to zero out a portion of
4229 endoff = base + size;
4230 if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff &&
4231 (m->valid & ((vm_page_bits_t)1 << (endoff >> DEV_BSHIFT))) == 0)
4232 pmap_zero_page_area(m, endoff,
4233 DEV_BSIZE - (endoff & (DEV_BSIZE - 1)));
4236 * Set valid, clear dirty bits. If validating the entire
4237 * page we can safely clear the pmap modify bit. We also
4238 * use this opportunity to clear the VPO_NOSYNC flag. If a process
4239 * takes a write fault on a MAP_NOSYNC memory area the flag will
4242 * We set valid bits inclusive of any overlap, but we can only
4243 * clear dirty bits for DEV_BSIZE chunks that are fully within
4246 oldvalid = m->valid;
4247 pagebits = vm_page_bits(base, size);
4248 m->valid |= pagebits;
4250 if ((frag = base & (DEV_BSIZE - 1)) != 0) {
4251 frag = DEV_BSIZE - frag;
4257 pagebits = vm_page_bits(base, size & (DEV_BSIZE - 1));
4259 if (base == 0 && size == PAGE_SIZE) {
4261 * The page can only be modified within the pmap if it is
4262 * mapped, and it can only be mapped if it was previously
4265 if (oldvalid == VM_PAGE_BITS_ALL)
4267 * Perform the pmap_clear_modify() first. Otherwise,
4268 * a concurrent pmap operation, such as
4269 * pmap_protect(), could clear a modification in the
4270 * pmap and set the dirty field on the page before
4271 * pmap_clear_modify() had begun and after the dirty
4272 * field was cleared here.
4274 pmap_clear_modify(m);
4276 m->oflags &= ~VPO_NOSYNC;
4277 } else if (oldvalid != VM_PAGE_BITS_ALL)
4278 m->dirty &= ~pagebits;
4280 vm_page_clear_dirty_mask(m, pagebits);
4284 vm_page_clear_dirty(vm_page_t m, int base, int size)
4287 vm_page_clear_dirty_mask(m, vm_page_bits(base, size));
4291 * vm_page_set_invalid:
4293 * Invalidates DEV_BSIZE'd chunks within a page. Both the
4294 * valid and dirty bits for the effected areas are cleared.
4297 vm_page_set_invalid(vm_page_t m, int base, int size)
4299 vm_page_bits_t bits;
4303 VM_OBJECT_ASSERT_WLOCKED(object);
4304 if (object->type == OBJT_VNODE && base == 0 && IDX_TO_OFF(m->pindex) +
4305 size >= object->un_pager.vnp.vnp_size)
4306 bits = VM_PAGE_BITS_ALL;
4308 bits = vm_page_bits(base, size);
4309 if (object->ref_count != 0 && m->valid == VM_PAGE_BITS_ALL &&
4312 KASSERT((bits == 0 && m->valid == VM_PAGE_BITS_ALL) ||
4313 !pmap_page_is_mapped(m),
4314 ("vm_page_set_invalid: page %p is mapped", m));
4320 * vm_page_zero_invalid()
4322 * The kernel assumes that the invalid portions of a page contain
4323 * garbage, but such pages can be mapped into memory by user code.
4324 * When this occurs, we must zero out the non-valid portions of the
4325 * page so user code sees what it expects.
4327 * Pages are most often semi-valid when the end of a file is mapped
4328 * into memory and the file's size is not page aligned.
4331 vm_page_zero_invalid(vm_page_t m, boolean_t setvalid)
4336 VM_OBJECT_ASSERT_WLOCKED(m->object);
4338 * Scan the valid bits looking for invalid sections that
4339 * must be zeroed. Invalid sub-DEV_BSIZE'd areas ( where the
4340 * valid bit may be set ) have already been zeroed by
4341 * vm_page_set_validclean().
4343 for (b = i = 0; i <= PAGE_SIZE / DEV_BSIZE; ++i) {
4344 if (i == (PAGE_SIZE / DEV_BSIZE) ||
4345 (m->valid & ((vm_page_bits_t)1 << i))) {
4347 pmap_zero_page_area(m,
4348 b << DEV_BSHIFT, (i - b) << DEV_BSHIFT);
4355 * setvalid is TRUE when we can safely set the zero'd areas
4356 * as being valid. We can do this if there are no cache consistancy
4357 * issues. e.g. it is ok to do with UFS, but not ok to do with NFS.
4360 m->valid = VM_PAGE_BITS_ALL;
4366 * Is (partial) page valid? Note that the case where size == 0
4367 * will return FALSE in the degenerate case where the page is
4368 * entirely invalid, and TRUE otherwise.
4371 vm_page_is_valid(vm_page_t m, int base, int size)
4373 vm_page_bits_t bits;
4375 VM_OBJECT_ASSERT_LOCKED(m->object);
4376 bits = vm_page_bits(base, size);
4377 return (m->valid != 0 && (m->valid & bits) == bits);
4381 * Returns true if all of the specified predicates are true for the entire
4382 * (super)page and false otherwise.
4385 vm_page_ps_test(vm_page_t m, int flags, vm_page_t skip_m)
4391 if (skip_m != NULL && skip_m->object != object)
4393 VM_OBJECT_ASSERT_LOCKED(object);
4394 npages = atop(pagesizes[m->psind]);
4397 * The physically contiguous pages that make up a superpage, i.e., a
4398 * page with a page size index ("psind") greater than zero, will
4399 * occupy adjacent entries in vm_page_array[].
4401 for (i = 0; i < npages; i++) {
4402 /* Always test object consistency, including "skip_m". */
4403 if (m[i].object != object)
4405 if (&m[i] == skip_m)
4407 if ((flags & PS_NONE_BUSY) != 0 && vm_page_busied(&m[i]))
4409 if ((flags & PS_ALL_DIRTY) != 0) {
4411 * Calling vm_page_test_dirty() or pmap_is_modified()
4412 * might stop this case from spuriously returning
4413 * "false". However, that would require a write lock
4414 * on the object containing "m[i]".
4416 if (m[i].dirty != VM_PAGE_BITS_ALL)
4419 if ((flags & PS_ALL_VALID) != 0 &&
4420 m[i].valid != VM_PAGE_BITS_ALL)
4427 * Set the page's dirty bits if the page is modified.
4430 vm_page_test_dirty(vm_page_t m)
4433 VM_OBJECT_ASSERT_WLOCKED(m->object);
4434 if (m->dirty != VM_PAGE_BITS_ALL && pmap_is_modified(m))
4439 vm_page_lock_KBI(vm_page_t m, const char *file, int line)
4442 mtx_lock_flags_(vm_page_lockptr(m), 0, file, line);
4446 vm_page_unlock_KBI(vm_page_t m, const char *file, int line)
4449 mtx_unlock_flags_(vm_page_lockptr(m), 0, file, line);
4453 vm_page_trylock_KBI(vm_page_t m, const char *file, int line)
4456 return (mtx_trylock_flags_(vm_page_lockptr(m), 0, file, line));
4459 #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
4461 vm_page_assert_locked_KBI(vm_page_t m, const char *file, int line)
4464 vm_page_lock_assert_KBI(m, MA_OWNED, file, line);
4468 vm_page_lock_assert_KBI(vm_page_t m, int a, const char *file, int line)
4471 mtx_assert_(vm_page_lockptr(m), a, file, line);
4477 vm_page_object_lock_assert(vm_page_t m)
4481 * Certain of the page's fields may only be modified by the
4482 * holder of the containing object's lock or the exclusive busy.
4483 * holder. Unfortunately, the holder of the write busy is
4484 * not recorded, and thus cannot be checked here.
4486 if (m->object != NULL && !vm_page_xbusied(m))
4487 VM_OBJECT_ASSERT_WLOCKED(m->object);
4491 vm_page_assert_pga_writeable(vm_page_t m, uint8_t bits)
4494 if ((bits & PGA_WRITEABLE) == 0)
4498 * The PGA_WRITEABLE flag can only be set if the page is
4499 * managed, is exclusively busied or the object is locked.
4500 * Currently, this flag is only set by pmap_enter().
4502 KASSERT((m->oflags & VPO_UNMANAGED) == 0,
4503 ("PGA_WRITEABLE on unmanaged page"));
4504 if (!vm_page_xbusied(m))
4505 VM_OBJECT_ASSERT_LOCKED(m->object);
4509 #include "opt_ddb.h"
4511 #include <sys/kernel.h>
4513 #include <ddb/ddb.h>
4515 DB_SHOW_COMMAND(page, vm_page_print_page_info)
4518 db_printf("vm_cnt.v_free_count: %d\n", vm_free_count());
4519 db_printf("vm_cnt.v_inactive_count: %d\n", vm_inactive_count());
4520 db_printf("vm_cnt.v_active_count: %d\n", vm_active_count());
4521 db_printf("vm_cnt.v_laundry_count: %d\n", vm_laundry_count());
4522 db_printf("vm_cnt.v_wire_count: %d\n", vm_wire_count());
4523 db_printf("vm_cnt.v_free_reserved: %d\n", vm_cnt.v_free_reserved);
4524 db_printf("vm_cnt.v_free_min: %d\n", vm_cnt.v_free_min);
4525 db_printf("vm_cnt.v_free_target: %d\n", vm_cnt.v_free_target);
4526 db_printf("vm_cnt.v_inactive_target: %d\n", vm_cnt.v_inactive_target);
4529 DB_SHOW_COMMAND(pageq, vm_page_print_pageq_info)
4533 db_printf("pq_free %d\n", vm_free_count());
4534 for (dom = 0; dom < vm_ndomains; dom++) {
4536 "dom %d page_cnt %d free %d pq_act %d pq_inact %d pq_laund %d pq_unsw %d\n",
4538 vm_dom[dom].vmd_page_count,
4539 vm_dom[dom].vmd_free_count,
4540 vm_dom[dom].vmd_pagequeues[PQ_ACTIVE].pq_cnt,
4541 vm_dom[dom].vmd_pagequeues[PQ_INACTIVE].pq_cnt,
4542 vm_dom[dom].vmd_pagequeues[PQ_LAUNDRY].pq_cnt,
4543 vm_dom[dom].vmd_pagequeues[PQ_UNSWAPPABLE].pq_cnt);
4547 DB_SHOW_COMMAND(pginfo, vm_page_print_pginfo)
4550 boolean_t phys, virt;
4553 db_printf("show pginfo addr\n");
4557 phys = strchr(modif, 'p') != NULL;
4558 virt = strchr(modif, 'v') != NULL;
4560 m = PHYS_TO_VM_PAGE(pmap_kextract(addr));
4562 m = PHYS_TO_VM_PAGE(addr);
4564 m = (vm_page_t)addr;
4566 "page %p obj %p pidx 0x%jx phys 0x%jx q %d hold %d wire %d\n"
4567 " af 0x%x of 0x%x f 0x%x act %d busy %x valid 0x%x dirty 0x%x\n",
4568 m, m->object, (uintmax_t)m->pindex, (uintmax_t)m->phys_addr,
4569 m->queue, m->hold_count, m->wire_count, m->aflags, m->oflags,
4570 m->flags, m->act_count, m->busy_lock, m->valid, m->dirty);