79#include "opt_ktrace.h"
84#include <sys/kernel.h>
90#include <sys/refcount.h>
91#include <sys/resourcevar.h>
92#include <sys/rwlock.h>
93#include <sys/signalvar.h>
94#include <sys/sysctl.h>
95#include <sys/sysent.h>
96#include <sys/vmmeter.h>
99#include <sys/ktrace.h>
117#define VM_FAULT_READ_DEFAULT (1 + VM_FAULT_READ_AHEAD_INIT)
119#define VM_FAULT_DONTNEED_MIN 1048576
175 int backward,
int forward,
bool obj_locked);
180 "Number of page allocation attempts in page fault handler before it "
181 "triggers OOM handling");
186 "Number of seconds to wait for free pages before retrying "
187 "the page fault handler");
237 if (fs->
vp != NULL) {
319#if VM_NRESERVLEVEL > 0
327 MPASS(fs->
vp == NULL);
341#if VM_NRESERVLEVEL > 0
343 (m_super = vm_reserv_to_superpage(m)) != NULL &&
344 rounddown2(vaddr, pagesizes[m_super->psind]) >= fs->
entry->
start &&
345 roundup2(vaddr + 1, pagesizes[m_super->psind]) <= fs->
entry->
end &&
347 (pagesizes[m_super->psind] - 1)) && !fs->
wired &&
348 pmap_ps_enabled(fs->
map->
pmap)) {
363 psind = m_super->psind;
364 vaddr = rounddown2(vaddr, pagesizes[psind]);
381 if (psind == 0 && !fs->
wired)
386 curthread->td_ru.ru_minflt++;
430 MPASS(first <= last);
444 vm_pindex_t map_first, map_last, pager_first, pager_last, pidx;
445 int bdry_idx, i, npages, psind, rv;
488 MPASS(pager_first <= pager_last);
491 MPASS(pager_last < fs->first_object->size);
515 KASSERT(PMAP_HAS_LARGEPAGES,
516 (
"missing pmap support for large pages"));
523 KASSERT((vaddr & (pagesizes[bdry_idx] - 1)) == 0,
524 (
"unaligned superpage start %#jx pager_first %#jx offset %#jx vaddr %#jx",
525 (uintmax_t)fs->
entry->
start, (uintmax_t)pager_first,
528 (
"unaligned superpage m %p %#jx", m,
540 for (i = 0; i < atop(pagesizes[bdry_idx]); i++)
558 if (map_first > pager_first) {
561 pager_first = map_first;
564 if (map_last < pager_last) {
567 pager_last = map_last;
575 if (psind > 0 && ((vaddr & (pagesizes[psind] - 1)) != 0 ||
576 pidx +
OFF_TO_IDX(pagesizes[psind]) - 1 > pager_last ||
580 npages = atop(pagesizes[psind]);
581 for (i = 0; i < npages; i++) {
598 if (__predict_false(psind > 0 &&
601 for (i = 0; i < npages; i++) {
609 for (i = 0; i < npages; i++) {
624 curthread->td_ru.ru_majflt++;
631 "Control signal to deliver on protection fault");
634#define UCODE_PAGEFLT 12
658 int fault_flags,
int *signo,
int *ucode)
662 MPASS(signo == NULL || ucode != NULL);
664 if (map !=
kernel_map && KTRPOINT(curthread, KTR_FAULT))
665 ktrfault(vaddr, fault_type);
667 result =
vm_fault(map, trunc_page(vaddr), fault_type, fault_flags,
674 (
"Unexpected Mach error %d from vm_fault()", result));
676 if (map !=
kernel_map && KTRPOINT(curthread, KTR_FAULTEND))
684 *ucode = SEGV_MAPERR;
701 if (SV_CURPROC_ABI() == SV_ABI_FREEBSD &&
702 curproc->p_osrel >= P_OSREL_SIGSEGV) {
704 *ucode = SEGV_ACCERR;
716 *ucode = SEGV_ACCERR;
720 KASSERT(0, (
"Unexpected Mach error %d from vm_fault()",
738 ASSERT_VOP_LOCKED(vp,
"saved vnode is not locked");
748 locked = VOP_ISLOCKED(vp);
749 if (locked != LK_EXCLUSIVE)
758 error = vget(vp, locked | LK_CANRECURSE | LK_NOWAIT);
769 error = vget(vp, locked | LK_RETRY | LK_CANRECURSE);
772 KASSERT(error == 0, (
"vm_fault: vget failed %d", error));
835 (
"vm_fault_lookup: Map already locked."));
847 panic(
"%s: fault on nofault entry, addr: %#lx",
848 __func__, (u_long)fs->
vaddr);
871 (
"!fs->wired && VM_FAULT_WIRE"));
881 vm_pindex_t retry_pindex;
893 &fs->
entry, &retry_object, &retry_pindex, &retry_prot,
916 fs->
prot &= retry_prot;
923 (
"!wired && VM_FAULT_WIRE"));
931 bool is_first_object_locked;
934 (
"source and target COW objects are identical"));
944 is_first_object_locked =
false;
969#if VM_NRESERVLEVEL > 0
980 VM_CNT_INC(v_cow_optim);
982 if (is_first_object_locked)
1030 VM_CNT_INC(v_cow_faults);
1031 curthread->td_cow++;
1061 if (next_object == NULL)
1064 KASSERT(fs->
object != next_object, (
"object loop %p", next_object));
1071 fs->
object = next_object;
1090 MPASS(fs->
m == NULL);
1097 if ((fs->
m->flags &
PG_ZERO) == 0) {
1100 VM_CNT_INC(v_ozfod);
1131 "proc %d (%s) failed to alloc page on fault, starting OOM\n",
1132 curproc->p_pid, curproc->p_comm);
1144 struct domainset *dset;
1176 panic(
"inconsistent return codes");
1194 dset = curthread->td_domain.dr_policy;
1195 if (!vm_page_count_severe_set(&dset->ds_mask) || P_KILLED(curproc)) {
1196#if VM_NRESERVLEVEL > 0
1202 if (fs->
m == NULL) {
1220 vm_offset_t e_end, e_start;
1221 int ahead, behind, cluster_offset, rv;
1248 if (fs->
nera == -1 && !P_KILLED(curproc))
1264 (
"vm_fault: vnode-backed object mapped by system map"));
1271 P_KILLED(curproc)) {
1291 behind = ulmin(cluster_offset,
1292 atop(fs->
vaddr - e_start));
1295 ahead = ulmin(ahead, atop(e_end - fs->
vaddr) - 1);
1303 printf(
"vm_fault: pager read error, pid %d (%s)\n",
1304 curproc->p_pid, curproc->p_comm);
1317 (
"%s: unepxected pager error %d", __func__, rv));
1352 VM_CNT_INC(v_intrans);
1388 if (fs->
m != NULL) {
1448 int fault_flags, vm_page_t *m_hold)
1451 int ahead, behind, faultcount, rv;
1455 VM_CNT_INC(v_vm_faults);
1457 if ((curthread->td_pflags & TDP_NOFAULTING) != 0)
1492 if (fs.
vp == NULL &&
1541 panic(
"vm_fault: Unhandled status %d", res);
1546 KASSERT(fs.
m == NULL,
1547 (
"page still set %p at loop start", fs.
m));
1554 faultcount = behind + 1 + ahead;
1570 panic(
"vm_fault: Unhandled status %d", res);
1618 if (faultcount == 0)
1622 fs.
prot &= ~VM_PROT_WRITE;
1656 (
"vm_fault: page %p partially invalid", fs.
m));
1671 faultcount > 0 ? behind :
PFBAK,
1672 faultcount > 0 ? ahead :
PFFOR,
false);
1694 VM_CNT_INC(v_io_faults);
1695 curthread->td_ru.ru_majflt++;
1700 racct_add_force(curproc, RACCT_WRITEBPS,
1701 PAGE_SIZE + behind * PAGE_SIZE);
1702 racct_add_force(curproc, RACCT_WRITEIOPS, 1);
1704 racct_add_force(curproc, RACCT_READBPS,
1705 PAGE_SIZE + ahead * PAGE_SIZE);
1706 racct_add_force(curproc, RACCT_READIOPS, 1);
1708 PROC_UNLOCK(curproc);
1712 curthread->td_ru.ru_minflt++;
1734 vm_offset_t end, start;
1735 vm_page_t
m, m_next;
1736 vm_pindex_t pend, pstart;
1746 if (MAXPAGESIZES > 1 && size < pagesizes[1])
1747 size = pagesizes[1];
1748 end = rounddown2(
vaddr, size);
1749 if (
vaddr - end >= size - PAGE_SIZE - ptoa(ahead) &&
1761 while ((
m = m_next) != NULL &&
m->pindex < pend) {
1762 m_next = TAILQ_NEXT(
m, listq);
1796 int backward,
int forward,
bool obj_locked)
1801 vm_offset_t addr, starta;
1807 if (pmap !=
vmspace_pmap(curthread->td_proc->p_vmspace))
1812 if (addra < backward * PAGE_SIZE) {
1815 starta = addra - backward * PAGE_SIZE;
1816 if (starta < entry->start)
1828 for (i = 0; i < 2 * imax(backward, forward); i++) {
1829 addr = addra + ((i >> 1) + 1) * ((i & 1) == 0 ? -PAGE_SIZE :
1831 if (addr > addra + forward * PAGE_SIZE)
1834 if (addr < starta || addr >=
entry->
end)
1848 0, (
"vm_fault_prefault: unaligned object offset"));
1853 lobject = backing_object;
1880 vm_offset_t end, va;
1883 boolean_t pmap_failed;
1887 end = round_page(addr + len);
1888 addr = trunc_page(addr);
1893 if (atop(end - addr) > max_count)
1894 panic(
"vm_fault_quick_hold_pages: count > max_count");
1895 count = atop(end - addr);
1901 pmap_failed = FALSE;
1902 for (mp = ma, va = addr; va < end; mp++, va += PAGE_SIZE) {
1907 (*mp)->dirty != VM_PAGE_BITS_ALL) {
1936 (curthread->td_pflags & TDP_NOFAULTING) != 0)
1938 for (mp = ma, va = addr; va < end; mp++, va += PAGE_SIZE)
1945 for (mp = ma; mp < ma + count; mp++)
1968 vm_ooffset_t *fork_charge)
1971 vm_pindex_t dst_pindex,
pindex, src_pindex;
1982 upgrade = src_entry == dst_entry;
1989 dst_object = src_object;
1998 dst_entry->
start), NULL, NULL, 0);
1999#if VM_NRESERVLEVEL > 0
2009 (
"vm_fault_copy_entry: vm_object not NULL"));
2010 if (src_object != dst_object) {
2013 dst_entry->
eflags &= ~MAP_ENTRY_VN_EXEC;
2015 if (fork_charge != NULL) {
2016 KASSERT(dst_entry->
cred == NULL,
2017 (
"vm_fault_copy_entry: leaked swp charge"));
2018 dst_object->
cred = curthread->td_ucred;
2019 crhold(dst_object->
cred);
2020 *fork_charge += dst_object->
charge;
2023 dst_object->
cred == NULL) {
2024 KASSERT(dst_entry->
cred != NULL, (
"no cred for entry %p",
2026 dst_object->
cred = dst_entry->
cred;
2027 dst_entry->
cred = NULL;
2041 access &= ~VM_PROT_WRITE;
2052 for (
vaddr = dst_entry->
start, dst_pindex = 0;
2053 vaddr < dst_entry->end;
2054 vaddr += PAGE_SIZE, dst_pindex++) {
2061 if (src_object != dst_object)
2063 object = src_object;
2064 pindex = src_pindex + dst_pindex;
2078 (
"vm_fault_copy_entry: main object missing page"));
2082 if (
object != dst_object)
2084 object = backing_object;
2086 KASSERT(src_m != NULL, (
"vm_fault_copy_entry: page missing"));
2088 if (
object != dst_object) {
2093 dst_object ? src_pindex : 0) + dst_pindex,
2095 if (dst_m == NULL) {
2104 dst_m->dirty = dst_m->valid = src_m->valid;
2109 if (dst_m->pindex >= dst_object->
size) {
2144 if (src_m != dst_m) {
2149 (
"dst_m %p is not wired", dst_m));
2173 return (curthread_pflags_set(TDP_NOFAULTING | TDP_RESETSPUR));
2180 curthread_pflags_restore(save);
void pmap_zero_page(vm_page_t)
void pmap_remove_all(vm_page_t m)
void pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot)
boolean_t pmap_is_prefaultable(pmap_t pmap, vm_offset_t va)
int pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, u_int flags, int8_t psind)
#define PMAP_ENTER_LARGEPAGE
void pmap_copy_page(vm_page_t, vm_page_t)
void pmap_advise(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, int advice)
#define PMAP_ENTER_NOSLEEP
vm_page_t pmap_extract_and_hold(pmap_t pmap, vm_offset_t va, vm_prot_t prot)
struct timeval oom_start_time
struct thread * wiring_thread
union vm_map_object object
vm_ooffset_t backing_object_offset
struct domainset_ref domain
blockcount_t paging_in_progress
struct vm_object * backing_object
_Static_assert(sizeof(struct uma_slab)==__offsetof(struct uma_slab, us_free), "us_free field must be last")
struct vm_object * vm_object
#define VM_PROT_QUICK_NOFAULT
#define VM_PROT_FAULT_LOOKUP
static void vm_fault_dontneed(const struct faultstate *fs, vm_offset_t vaddr, int ahead)
static enum fault_status vm_fault_soft_fast(struct faultstate *fs)
static int vm_fault_relookup(struct faultstate *fs)
static void unlock_and_deallocate(struct faultstate *fs)
void vm_fault_copy_entry(vm_map_t dst_map, vm_map_t src_map, vm_map_entry_t dst_entry, vm_map_entry_t src_entry, vm_ooffset_t *fork_charge)
int vm_fault_trap(vm_map_t map, vm_offset_t vaddr, vm_prot_t fault_type, int fault_flags, int *signo, int *ucode)
static void vm_fault_dirty(struct faultstate *fs, vm_page_t m)
static void vm_fault_cow(struct faultstate *fs)
int vm_fault(vm_map_t map, vm_offset_t vaddr, vm_prot_t fault_type, int fault_flags, vm_page_t *m_hold)
static enum fault_status vm_fault_populate(struct faultstate *fs)
static enum fault_status vm_fault_lock_vnode(struct faultstate *fs, bool objlocked)
static void unlock_map(struct faultstate *fs)
SYSCTL_INT(_vm, OID_AUTO, pfault_oom_attempts, CTLFLAG_RWTUN, &vm_pfault_oom_attempts, 0, "Number of page allocation attempts in page fault handler before it " "triggers OOM handling")
static void vm_fault_restore_map_lock(struct faultstate *fs)
#define VM_FAULT_READ_DEFAULT
static void fault_page_free(vm_page_t *mp)
static bool vm_fault_next(struct faultstate *fs)
@ FAULT_PROTECTION_FAILURE
static void fault_deallocate(struct faultstate *fs)
static void unlock_vp(struct faultstate *fs)
int vm_fault_quick_hold_pages(vm_map_t map, vm_offset_t addr, vm_size_t len, vm_prot_t prot, vm_page_t *ma, int max_count)
static void vm_fault_prefault(const struct faultstate *fs, vm_offset_t addra, int backward, int forward, bool obj_locked)
static int prot_fault_translation
static void vm_fault_zerofill(struct faultstate *fs)
#define VM_FAULT_DONTNEED_MIN
static void fault_page_release(vm_page_t *mp)
static enum fault_status vm_fault_object(struct faultstate *fs, int *behindp, int *aheadp)
static enum fault_status vm_fault_getpages(struct faultstate *fs, int *behindp, int *aheadp)
static int vm_fault_lookup(struct faultstate *fs)
static int vm_pfault_oom_wait
static bool vm_fault_allocate_oom(struct faultstate *fs)
static int vm_pfault_oom_attempts
int vm_fault_disable_pagefaults(void)
void vm_fault_enable_pagefaults(int save)
static int vm_fault_readahead(struct faultstate *fs)
static void vm_fault_busy_sleep(struct faultstate *fs)
static enum fault_status vm_fault_allocate(struct faultstate *fs)
static void vm_fault_populate_cleanup(vm_object_t object, vm_pindex_t first, vm_pindex_t last)
static void vm_fault_populate_check_page(vm_page_t m)
void vm_map_lookup_done(vm_map_t map, vm_map_entry_t entry)
boolean_t vm_map_lookup_entry(vm_map_t map, vm_offset_t address, vm_map_entry_t *entry)
int vm_map_lookup_locked(vm_map_t *var_map, vm_offset_t vaddr, vm_prot_t fault_typea, vm_map_entry_t *out_entry, vm_object_t *object, vm_pindex_t *pindex, vm_prot_t *out_prot, boolean_t *wired)
int vm_map_lookup(vm_map_t *var_map, vm_offset_t vaddr, vm_prot_t fault_typea, vm_map_entry_t *out_entry, vm_object_t *object, vm_pindex_t *pindex, vm_prot_t *out_prot, boolean_t *wired)
#define VM_FAULT_READ_AHEAD_MAX
#define MAP_ENTRY_NEEDS_COPY
#define MAP_ENTRY_SPLIT_BOUNDARY_SHIFT
#define MAP_ENTRY_BEHAV_RANDOM
#define vm_map_unlock_read(map)
static bool vm_map_range_valid(vm_map_t map, vm_offset_t start, vm_offset_t end)
#define VM_FAULT_READ_AHEAD_MIN
#define vm_map_lock_read(map)
#define vm_map_trylock_read(map)
static __inline u_char vm_map_entry_behavior(vm_map_entry_t entry)
#define MAP_ENTRY_NEEDS_WAKEUP
static __inline pmap_t vmspace_pmap(struct vmspace *vmspace)
#define MAP_ENTRY_NOFAULT
#define MAP_ENTRY_BEHAV_SEQUENTIAL
#define MAP_ENTRY_IN_TRANSITION
#define MAP_ENTRY_SPLIT_BOUNDARY_MASK
#define vm_map_unlock_and_wait(map, timo)
#define vm_map_unlock(map)
void vm_object_reference(vm_object_t object)
vm_object_t vm_object_allocate_anon(vm_pindex_t size, vm_object_t backing_object, struct ucred *cred, vm_size_t charge)
void vm_object_busy(vm_object_t obj)
void vm_object_pip_add(vm_object_t object, short i)
void vm_object_pip_wakeup(vm_object_t object)
void vm_object_reference_locked(vm_object_t object)
void vm_object_deallocate(vm_object_t object)
void vm_object_unbusy(vm_object_t obj)
#define VM_OBJECT_ASSERT_UNLOCKED(object)
void vm_object_set_writeable_dirty(vm_object_t)
#define VM_OBJECT_RLOCK(object)
#define VM_OBJECT_RUNLOCK(object)
static __inline void vm_object_color(vm_object_t object, u_short color)
#define VM_OBJECT_TRYWLOCK(object)
#define VM_OBJECT_WLOCK(object)
#define VM_OBJECT_WUNLOCK(object)
#define VM_OBJECT_TRYUPGRADE(object)
#define VM_OBJECT_ASSERT_WLOCKED(object)
void vm_page_activate(vm_page_t m)
void vm_page_deactivate(vm_page_t m)
vm_page_t vm_page_alloc(vm_object_t object, vm_pindex_t pindex, int req)
void vm_page_wire(vm_page_t m)
vm_page_t vm_page_lookup(vm_object_t object, vm_pindex_t pindex)
void vm_page_replace(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex, vm_page_t mold)
bool vm_page_busy_acquire(vm_page_t m, int allocflags)
int vm_page_tryxbusy(vm_page_t m)
void vm_waitpfault(struct domainset *dset, int timo)
vm_page_t vm_page_find_least(vm_object_t object, vm_pindex_t pindex)
void vm_page_valid(vm_page_t m)
vm_page_t vm_page_next(vm_page_t m)
bool vm_page_ps_test(vm_page_t m, int flags, vm_page_t skip_m)
vm_page_bits_t vm_page_set_dirty(vm_page_t m)
bool vm_page_busy_sleep(vm_page_t m, const char *wmesg, int allocflags)
void vm_wait(vm_object_t obj)
void vm_page_unwire(vm_page_t m, uint8_t nqueue)
void vm_page_free(vm_page_t m)
bool vm_page_remove_xbusy(vm_page_t m)
static void vm_page_aflag_set(vm_page_t m, uint16_t bits)
static bool vm_page_inactive(vm_page_t m)
#define vm_page_assert_xbusied(m)
static bool vm_page_all_valid(vm_page_t m)
#define VM_PAGE_OBJECT_BUSY_ASSERT(m)
#define vm_page_busied(m)
#define VM_ALLOC_WAITFAIL
static void vm_page_aflag_clear(vm_page_t m, uint16_t bits)
#define vm_page_xunbusy(m)
static __inline void vm_page_dirty(vm_page_t m)
static bool vm_page_wired(vm_page_t m)
#define VM_PAGE_TO_PHYS(entry)
#define vm_page_xbusied(m)
void vm_pageout_oom(int shortage)
#define KERN_RESOURCE_SHORTAGE
#define KERN_PROTECTION_FAILURE
#define KERN_OUT_OF_BOUNDS
#define KERN_INVALID_ADDRESS