2 #include <linux/vmacache.h>
3 #include <linux/hugetlb.h>
4 #include <linux/huge_mm.h>
5 #include <linux/mount.h>
6 #include <linux/seq_file.h>
7 #include <linux/highmem.h>
8 #include <linux/ptrace.h>
9 #include <linux/slab.h>
10 #include <linux/pagemap.h>
11 #include <linux/mempolicy.h>
12 #include <linux/rmap.h>
13 #include <linux/swap.h>
14 #include <linux/swapops.h>
15 #include <linux/mmu_notifier.h>
18 #include <asm/uaccess.h>
19 #include <asm/tlbflush.h>
22 void task_mem(struct seq_file *m, struct mm_struct *mm)
24 unsigned long data, text, lib, swap, ptes, pmds;
25 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
28 * Note: to minimize their overhead, mm maintains hiwater_vm and
29 * hiwater_rss only when about to *lower* total_vm or rss. Any
30 * collector of these hiwater stats must therefore get total_vm
31 * and rss too, which will usually be the higher. Barriers? not
32 * worth the effort, such snapshots can always be inconsistent.
34 hiwater_vm = total_vm = mm->total_vm;
35 if (hiwater_vm < mm->hiwater_vm)
36 hiwater_vm = mm->hiwater_vm;
37 hiwater_rss = total_rss = get_mm_rss(mm);
38 if (hiwater_rss < mm->hiwater_rss)
39 hiwater_rss = mm->hiwater_rss;
41 data = mm->total_vm - mm->shared_vm - mm->stack_vm;
42 text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10;
43 lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text;
44 swap = get_mm_counter(mm, MM_SWAPENTS);
45 ptes = PTRS_PER_PTE * sizeof(pte_t) * atomic_long_read(&mm->nr_ptes);
46 pmds = PTRS_PER_PMD * sizeof(pmd_t) * mm_nr_pmds(mm);
61 hiwater_vm << (PAGE_SHIFT-10),
62 total_vm << (PAGE_SHIFT-10),
63 mm->locked_vm << (PAGE_SHIFT-10),
64 mm->pinned_vm << (PAGE_SHIFT-10),
65 hiwater_rss << (PAGE_SHIFT-10),
66 total_rss << (PAGE_SHIFT-10),
67 data << (PAGE_SHIFT-10),
68 mm->stack_vm << (PAGE_SHIFT-10), text, lib,
71 swap << (PAGE_SHIFT-10));
74 unsigned long task_vsize(struct mm_struct *mm)
76 return PAGE_SIZE * mm->total_vm;
79 unsigned long task_statm(struct mm_struct *mm,
80 unsigned long *shared, unsigned long *text,
81 unsigned long *data, unsigned long *resident)
83 *shared = get_mm_counter(mm, MM_FILEPAGES);
84 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
86 *data = mm->total_vm - mm->shared_vm;
87 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
93 * Save get_task_policy() for show_numa_map().
95 static void hold_task_mempolicy(struct proc_maps_private *priv)
97 struct task_struct *task = priv->task;
100 priv->task_mempolicy = get_task_policy(task);
101 mpol_get(priv->task_mempolicy);
104 static void release_task_mempolicy(struct proc_maps_private *priv)
106 mpol_put(priv->task_mempolicy);
109 static void hold_task_mempolicy(struct proc_maps_private *priv)
112 static void release_task_mempolicy(struct proc_maps_private *priv)
117 static void vma_stop(struct proc_maps_private *priv)
119 struct mm_struct *mm = priv->mm;
121 release_task_mempolicy(priv);
122 up_read(&mm->mmap_sem);
126 static struct vm_area_struct *
127 m_next_vma(struct proc_maps_private *priv, struct vm_area_struct *vma)
129 if (vma == priv->tail_vma)
131 return vma->vm_next ?: priv->tail_vma;
134 static void m_cache_vma(struct seq_file *m, struct vm_area_struct *vma)
136 if (m->count < m->size) /* vma is copied successfully */
137 m->version = m_next_vma(m->private, vma) ? vma->vm_start : -1UL;
140 static void *m_start(struct seq_file *m, loff_t *ppos)
142 struct proc_maps_private *priv = m->private;
143 unsigned long last_addr = m->version;
144 struct mm_struct *mm;
145 struct vm_area_struct *vma;
146 unsigned int pos = *ppos;
148 /* See m_cache_vma(). Zero at the start or after lseek. */
149 if (last_addr == -1UL)
152 priv->task = get_proc_task(priv->inode);
154 return ERR_PTR(-ESRCH);
157 if (!mm || !atomic_inc_not_zero(&mm->mm_users))
160 down_read(&mm->mmap_sem);
161 hold_task_mempolicy(priv);
162 priv->tail_vma = get_gate_vma(mm);
165 vma = find_vma(mm, last_addr);
166 if (vma && (vma = m_next_vma(priv, vma)))
171 if (pos < mm->map_count) {
172 for (vma = mm->mmap; pos; pos--) {
173 m->version = vma->vm_start;
179 /* we do not bother to update m->version in this case */
180 if (pos == mm->map_count && priv->tail_vma)
181 return priv->tail_vma;
187 static void *m_next(struct seq_file *m, void *v, loff_t *pos)
189 struct proc_maps_private *priv = m->private;
190 struct vm_area_struct *next;
193 next = m_next_vma(priv, v);
199 static void m_stop(struct seq_file *m, void *v)
201 struct proc_maps_private *priv = m->private;
203 if (!IS_ERR_OR_NULL(v))
206 put_task_struct(priv->task);
211 static int proc_maps_open(struct inode *inode, struct file *file,
212 const struct seq_operations *ops, int psize)
214 struct proc_maps_private *priv = __seq_open_private(file, ops, psize);
220 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
221 if (IS_ERR(priv->mm)) {
222 int err = PTR_ERR(priv->mm);
224 seq_release_private(inode, file);
231 static int proc_map_release(struct inode *inode, struct file *file)
233 struct seq_file *seq = file->private_data;
234 struct proc_maps_private *priv = seq->private;
239 return seq_release_private(inode, file);
242 static int do_maps_open(struct inode *inode, struct file *file,
243 const struct seq_operations *ops)
245 return proc_maps_open(inode, file, ops,
246 sizeof(struct proc_maps_private));
249 static pid_t pid_of_stack(struct proc_maps_private *priv,
250 struct vm_area_struct *vma, bool is_pid)
252 struct inode *inode = priv->inode;
253 struct task_struct *task;
257 task = pid_task(proc_pid(inode), PIDTYPE_PID);
259 task = task_of_stack(task, vma, is_pid);
261 ret = task_pid_nr_ns(task, inode->i_sb->s_fs_info);
269 show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid)
271 struct mm_struct *mm = vma->vm_mm;
272 struct file *file = vma->vm_file;
273 struct proc_maps_private *priv = m->private;
274 vm_flags_t flags = vma->vm_flags;
275 unsigned long ino = 0;
276 unsigned long long pgoff = 0;
277 unsigned long start, end;
279 const char *name = NULL;
282 struct inode *inode = file_inode(vma->vm_file);
283 dev = inode->i_sb->s_dev;
285 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
288 /* We don't show the stack guard page in /proc/maps */
289 start = vma->vm_start;
290 if (stack_guard_page_start(vma, start))
293 if (stack_guard_page_end(vma, end))
296 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
297 seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu ",
300 flags & VM_READ ? 'r' : '-',
301 flags & VM_WRITE ? 'w' : '-',
302 flags & VM_EXEC ? 'x' : '-',
303 flags & VM_MAYSHARE ? 's' : 'p',
305 MAJOR(dev), MINOR(dev), ino);
308 * Print the dentry name for named mappings, and a
309 * special [heap] marker for the heap:
313 seq_file_path(m, file, "\n");
317 if (vma->vm_ops && vma->vm_ops->name) {
318 name = vma->vm_ops->name(vma);
323 name = arch_vma_name(vma);
332 if (vma->vm_start <= mm->brk &&
333 vma->vm_end >= mm->start_brk) {
338 tid = pid_of_stack(priv, vma, is_pid);
341 * Thread stack in /proc/PID/task/TID/maps or
342 * the main process stack.
344 if (!is_pid || (vma->vm_start <= mm->start_stack &&
345 vma->vm_end >= mm->start_stack)) {
348 /* Thread stack in /proc/PID/maps */
350 seq_printf(m, "[stack:%d]", tid);
363 static int show_map(struct seq_file *m, void *v, int is_pid)
365 show_map_vma(m, v, is_pid);
370 static int show_pid_map(struct seq_file *m, void *v)
372 return show_map(m, v, 1);
375 static int show_tid_map(struct seq_file *m, void *v)
377 return show_map(m, v, 0);
380 static const struct seq_operations proc_pid_maps_op = {
387 static const struct seq_operations proc_tid_maps_op = {
394 static int pid_maps_open(struct inode *inode, struct file *file)
396 return do_maps_open(inode, file, &proc_pid_maps_op);
399 static int tid_maps_open(struct inode *inode, struct file *file)
401 return do_maps_open(inode, file, &proc_tid_maps_op);
404 const struct file_operations proc_pid_maps_operations = {
405 .open = pid_maps_open,
408 .release = proc_map_release,
411 const struct file_operations proc_tid_maps_operations = {
412 .open = tid_maps_open,
415 .release = proc_map_release,
419 * Proportional Set Size(PSS): my share of RSS.
421 * PSS of a process is the count of pages it has in memory, where each
422 * page is divided by the number of processes sharing it. So if a
423 * process has 1000 pages all to itself, and 1000 shared with one other
424 * process, its PSS will be 1500.
426 * To keep (accumulated) division errors low, we adopt a 64bit
427 * fixed-point pss counter to minimize division errors. So (pss >>
428 * PSS_SHIFT) would be the real byte count.
430 * A shift of 12 before division means (assuming 4K page size):
431 * - 1M 3-user-pages add up to 8KB errors;
432 * - supports mapcount up to 2^24, or 16M;
433 * - supports PSS up to 2^52 bytes, or 4PB.
437 #ifdef CONFIG_PROC_PAGE_MONITOR
438 struct mem_size_stats {
439 unsigned long resident;
440 unsigned long shared_clean;
441 unsigned long shared_dirty;
442 unsigned long private_clean;
443 unsigned long private_dirty;
444 unsigned long referenced;
445 unsigned long anonymous;
446 unsigned long anonymous_thp;
451 static void smaps_account(struct mem_size_stats *mss, struct page *page,
452 unsigned long size, bool young, bool dirty)
457 mss->anonymous += size;
459 mss->resident += size;
460 /* Accumulate the size in pages that have been accessed. */
461 if (young || PageReferenced(page))
462 mss->referenced += size;
463 mapcount = page_mapcount(page);
467 if (dirty || PageDirty(page))
468 mss->shared_dirty += size;
470 mss->shared_clean += size;
471 pss_delta = (u64)size << PSS_SHIFT;
472 do_div(pss_delta, mapcount);
473 mss->pss += pss_delta;
475 if (dirty || PageDirty(page))
476 mss->private_dirty += size;
478 mss->private_clean += size;
479 mss->pss += (u64)size << PSS_SHIFT;
483 static void smaps_pte_entry(pte_t *pte, unsigned long addr,
484 struct mm_walk *walk)
486 struct mem_size_stats *mss = walk->private;
487 struct vm_area_struct *vma = walk->vma;
488 struct page *page = NULL;
490 if (pte_present(*pte)) {
491 page = vm_normal_page(vma, addr, *pte);
492 } else if (is_swap_pte(*pte)) {
493 swp_entry_t swpent = pte_to_swp_entry(*pte);
495 if (!non_swap_entry(swpent))
496 mss->swap += PAGE_SIZE;
497 else if (is_migration_entry(swpent))
498 page = migration_entry_to_page(swpent);
503 smaps_account(mss, page, PAGE_SIZE, pte_young(*pte), pte_dirty(*pte));
506 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
507 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
508 struct mm_walk *walk)
510 struct mem_size_stats *mss = walk->private;
511 struct vm_area_struct *vma = walk->vma;
514 /* FOLL_DUMP will return -EFAULT on huge zero page */
515 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
516 if (IS_ERR_OR_NULL(page))
518 mss->anonymous_thp += HPAGE_PMD_SIZE;
519 smaps_account(mss, page, HPAGE_PMD_SIZE,
520 pmd_young(*pmd), pmd_dirty(*pmd));
523 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
524 struct mm_walk *walk)
529 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
530 struct mm_walk *walk)
532 struct vm_area_struct *vma = walk->vma;
536 if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
537 smaps_pmd_entry(pmd, addr, walk);
542 if (pmd_trans_unstable(pmd))
545 * The mmap_sem held all the way back in m_start() is what
546 * keeps khugepaged out of here and from collapsing things
549 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
550 for (; addr != end; pte++, addr += PAGE_SIZE)
551 smaps_pte_entry(pte, addr, walk);
552 pte_unmap_unlock(pte - 1, ptl);
557 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
560 * Don't forget to update Documentation/ on changes.
562 static const char mnemonics[BITS_PER_LONG][2] = {
564 * In case if we meet a flag we don't know about.
566 [0 ... (BITS_PER_LONG-1)] = "??",
568 [ilog2(VM_READ)] = "rd",
569 [ilog2(VM_WRITE)] = "wr",
570 [ilog2(VM_EXEC)] = "ex",
571 [ilog2(VM_SHARED)] = "sh",
572 [ilog2(VM_MAYREAD)] = "mr",
573 [ilog2(VM_MAYWRITE)] = "mw",
574 [ilog2(VM_MAYEXEC)] = "me",
575 [ilog2(VM_MAYSHARE)] = "ms",
576 [ilog2(VM_GROWSDOWN)] = "gd",
577 [ilog2(VM_PFNMAP)] = "pf",
578 [ilog2(VM_DENYWRITE)] = "dw",
579 #ifdef CONFIG_X86_INTEL_MPX
580 [ilog2(VM_MPX)] = "mp",
582 [ilog2(VM_LOCKED)] = "lo",
583 [ilog2(VM_IO)] = "io",
584 [ilog2(VM_SEQ_READ)] = "sr",
585 [ilog2(VM_RAND_READ)] = "rr",
586 [ilog2(VM_DONTCOPY)] = "dc",
587 [ilog2(VM_DONTEXPAND)] = "de",
588 [ilog2(VM_ACCOUNT)] = "ac",
589 [ilog2(VM_NORESERVE)] = "nr",
590 [ilog2(VM_HUGETLB)] = "ht",
591 [ilog2(VM_ARCH_1)] = "ar",
592 [ilog2(VM_DONTDUMP)] = "dd",
593 #ifdef CONFIG_MEM_SOFT_DIRTY
594 [ilog2(VM_SOFTDIRTY)] = "sd",
596 [ilog2(VM_MIXEDMAP)] = "mm",
597 [ilog2(VM_HUGEPAGE)] = "hg",
598 [ilog2(VM_NOHUGEPAGE)] = "nh",
599 [ilog2(VM_MERGEABLE)] = "mg",
600 [ilog2(VM_UFFD_MISSING)]= "um",
601 [ilog2(VM_UFFD_WP)] = "uw",
605 seq_puts(m, "VmFlags: ");
606 for (i = 0; i < BITS_PER_LONG; i++) {
607 if (vma->vm_flags & (1UL << i)) {
608 seq_printf(m, "%c%c ",
609 mnemonics[i][0], mnemonics[i][1]);
615 static int show_smap(struct seq_file *m, void *v, int is_pid)
617 struct vm_area_struct *vma = v;
618 struct mem_size_stats mss;
619 struct mm_walk smaps_walk = {
620 .pmd_entry = smaps_pte_range,
625 memset(&mss, 0, sizeof mss);
626 /* mmap_sem is held in m_start */
627 walk_page_vma(vma, &smaps_walk);
629 show_map_vma(m, vma, is_pid);
635 "Shared_Clean: %8lu kB\n"
636 "Shared_Dirty: %8lu kB\n"
637 "Private_Clean: %8lu kB\n"
638 "Private_Dirty: %8lu kB\n"
639 "Referenced: %8lu kB\n"
640 "Anonymous: %8lu kB\n"
641 "AnonHugePages: %8lu kB\n"
643 "KernelPageSize: %8lu kB\n"
644 "MMUPageSize: %8lu kB\n"
646 (vma->vm_end - vma->vm_start) >> 10,
648 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)),
649 mss.shared_clean >> 10,
650 mss.shared_dirty >> 10,
651 mss.private_clean >> 10,
652 mss.private_dirty >> 10,
653 mss.referenced >> 10,
655 mss.anonymous_thp >> 10,
657 vma_kernel_pagesize(vma) >> 10,
658 vma_mmu_pagesize(vma) >> 10,
659 (vma->vm_flags & VM_LOCKED) ?
660 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0);
662 show_smap_vma_flags(m, vma);
667 static int show_pid_smap(struct seq_file *m, void *v)
669 return show_smap(m, v, 1);
672 static int show_tid_smap(struct seq_file *m, void *v)
674 return show_smap(m, v, 0);
677 static const struct seq_operations proc_pid_smaps_op = {
681 .show = show_pid_smap
684 static const struct seq_operations proc_tid_smaps_op = {
688 .show = show_tid_smap
691 static int pid_smaps_open(struct inode *inode, struct file *file)
693 return do_maps_open(inode, file, &proc_pid_smaps_op);
696 static int tid_smaps_open(struct inode *inode, struct file *file)
698 return do_maps_open(inode, file, &proc_tid_smaps_op);
701 const struct file_operations proc_pid_smaps_operations = {
702 .open = pid_smaps_open,
705 .release = proc_map_release,
708 const struct file_operations proc_tid_smaps_operations = {
709 .open = tid_smaps_open,
712 .release = proc_map_release,
715 enum clear_refs_types {
719 CLEAR_REFS_SOFT_DIRTY,
720 CLEAR_REFS_MM_HIWATER_RSS,
724 struct clear_refs_private {
725 enum clear_refs_types type;
728 #ifdef CONFIG_MEM_SOFT_DIRTY
729 static inline void clear_soft_dirty(struct vm_area_struct *vma,
730 unsigned long addr, pte_t *pte)
733 * The soft-dirty tracker uses #PF-s to catch writes
734 * to pages, so write-protect the pte as well. See the
735 * Documentation/vm/soft-dirty.txt for full description
736 * of how soft-dirty works.
740 if (pte_present(ptent)) {
741 ptent = pte_wrprotect(ptent);
742 ptent = pte_clear_flags(ptent, _PAGE_SOFT_DIRTY);
743 } else if (is_swap_pte(ptent)) {
744 ptent = pte_swp_clear_soft_dirty(ptent);
747 set_pte_at(vma->vm_mm, addr, pte, ptent);
750 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
751 unsigned long addr, pmd_t *pmdp)
755 pmd = pmd_wrprotect(pmd);
756 pmd = pmd_clear_flags(pmd, _PAGE_SOFT_DIRTY);
758 if (vma->vm_flags & VM_SOFTDIRTY)
759 vma->vm_flags &= ~VM_SOFTDIRTY;
761 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
766 static inline void clear_soft_dirty(struct vm_area_struct *vma,
767 unsigned long addr, pte_t *pte)
771 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
772 unsigned long addr, pmd_t *pmdp)
777 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
778 unsigned long end, struct mm_walk *walk)
780 struct clear_refs_private *cp = walk->private;
781 struct vm_area_struct *vma = walk->vma;
786 if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
787 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
788 clear_soft_dirty_pmd(vma, addr, pmd);
792 page = pmd_page(*pmd);
794 /* Clear accessed and referenced bits. */
795 pmdp_test_and_clear_young(vma, addr, pmd);
796 ClearPageReferenced(page);
802 if (pmd_trans_unstable(pmd))
805 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
806 for (; addr != end; pte++, addr += PAGE_SIZE) {
809 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
810 clear_soft_dirty(vma, addr, pte);
814 if (!pte_present(ptent))
817 page = vm_normal_page(vma, addr, ptent);
821 /* Clear accessed and referenced bits. */
822 ptep_test_and_clear_young(vma, addr, pte);
823 ClearPageReferenced(page);
825 pte_unmap_unlock(pte - 1, ptl);
830 static int clear_refs_test_walk(unsigned long start, unsigned long end,
831 struct mm_walk *walk)
833 struct clear_refs_private *cp = walk->private;
834 struct vm_area_struct *vma = walk->vma;
836 if (vma->vm_flags & VM_PFNMAP)
840 * Writing 1 to /proc/pid/clear_refs affects all pages.
841 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages.
842 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages.
843 * Writing 4 to /proc/pid/clear_refs affects all pages.
845 if (cp->type == CLEAR_REFS_ANON && vma->vm_file)
847 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file)
852 static ssize_t clear_refs_write(struct file *file, const char __user *buf,
853 size_t count, loff_t *ppos)
855 struct task_struct *task;
856 char buffer[PROC_NUMBUF];
857 struct mm_struct *mm;
858 struct vm_area_struct *vma;
859 enum clear_refs_types type;
863 memset(buffer, 0, sizeof(buffer));
864 if (count > sizeof(buffer) - 1)
865 count = sizeof(buffer) - 1;
866 if (copy_from_user(buffer, buf, count))
868 rv = kstrtoint(strstrip(buffer), 10, &itype);
871 type = (enum clear_refs_types)itype;
872 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
875 task = get_proc_task(file_inode(file));
878 mm = get_task_mm(task);
880 struct clear_refs_private cp = {
883 struct mm_walk clear_refs_walk = {
884 .pmd_entry = clear_refs_pte_range,
885 .test_walk = clear_refs_test_walk,
890 if (type == CLEAR_REFS_MM_HIWATER_RSS) {
892 * Writing 5 to /proc/pid/clear_refs resets the peak
893 * resident set size to this mm's current rss value.
895 down_write(&mm->mmap_sem);
896 reset_mm_hiwater_rss(mm);
897 up_write(&mm->mmap_sem);
901 down_read(&mm->mmap_sem);
902 if (type == CLEAR_REFS_SOFT_DIRTY) {
903 for (vma = mm->mmap; vma; vma = vma->vm_next) {
904 if (!(vma->vm_flags & VM_SOFTDIRTY))
906 up_read(&mm->mmap_sem);
907 down_write(&mm->mmap_sem);
908 for (vma = mm->mmap; vma; vma = vma->vm_next) {
909 vma->vm_flags &= ~VM_SOFTDIRTY;
910 vma_set_page_prot(vma);
912 downgrade_write(&mm->mmap_sem);
915 mmu_notifier_invalidate_range_start(mm, 0, -1);
917 walk_page_range(0, ~0UL, &clear_refs_walk);
918 if (type == CLEAR_REFS_SOFT_DIRTY)
919 mmu_notifier_invalidate_range_end(mm, 0, -1);
921 up_read(&mm->mmap_sem);
925 put_task_struct(task);
930 const struct file_operations proc_clear_refs_operations = {
931 .write = clear_refs_write,
932 .llseek = noop_llseek,
940 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */
941 pagemap_entry_t *buffer;
945 #define PAGEMAP_WALK_SIZE (PMD_SIZE)
946 #define PAGEMAP_WALK_MASK (PMD_MASK)
948 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t)
949 #define PM_PFRAME_BITS 55
950 #define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0)
951 #define PM_SOFT_DIRTY BIT_ULL(55)
952 #define PM_FILE BIT_ULL(61)
953 #define PM_SWAP BIT_ULL(62)
954 #define PM_PRESENT BIT_ULL(63)
956 #define PM_END_OF_BUFFER 1
958 static inline pagemap_entry_t make_pme(u64 frame, u64 flags)
960 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags };
963 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme,
964 struct pagemapread *pm)
966 pm->buffer[pm->pos++] = *pme;
967 if (pm->pos >= pm->len)
968 return PM_END_OF_BUFFER;
972 static int pagemap_pte_hole(unsigned long start, unsigned long end,
973 struct mm_walk *walk)
975 struct pagemapread *pm = walk->private;
976 unsigned long addr = start;
980 struct vm_area_struct *vma = find_vma(walk->mm, addr);
981 pagemap_entry_t pme = make_pme(0, 0);
982 /* End of address space hole, which we mark as non-present. */
983 unsigned long hole_end;
986 hole_end = min(end, vma->vm_start);
990 for (; addr < hole_end; addr += PAGE_SIZE) {
991 err = add_to_pagemap(addr, &pme, pm);
999 /* Addresses in the VMA. */
1000 if (vma->vm_flags & VM_SOFTDIRTY)
1001 pme = make_pme(0, PM_SOFT_DIRTY);
1002 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) {
1003 err = add_to_pagemap(addr, &pme, pm);
1012 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm,
1013 struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1015 u64 frame = 0, flags = 0;
1016 struct page *page = NULL;
1018 if (pte_present(pte)) {
1020 frame = pte_pfn(pte);
1021 flags |= PM_PRESENT;
1022 page = vm_normal_page(vma, addr, pte);
1023 if (pte_soft_dirty(pte))
1024 flags |= PM_SOFT_DIRTY;
1025 } else if (is_swap_pte(pte)) {
1027 if (pte_swp_soft_dirty(pte))
1028 flags |= PM_SOFT_DIRTY;
1029 entry = pte_to_swp_entry(pte);
1030 frame = swp_type(entry) |
1031 (swp_offset(entry) << MAX_SWAPFILES_SHIFT);
1033 if (is_migration_entry(entry))
1034 page = migration_entry_to_page(entry);
1037 if (page && !PageAnon(page))
1039 if (vma->vm_flags & VM_SOFTDIRTY)
1040 flags |= PM_SOFT_DIRTY;
1042 return make_pme(frame, flags);
1045 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
1046 struct mm_walk *walk)
1048 struct vm_area_struct *vma = walk->vma;
1049 struct pagemapread *pm = walk->private;
1051 pte_t *pte, *orig_pte;
1054 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1055 if (pmd_trans_huge_lock(pmdp, vma, &ptl) == 1) {
1056 u64 flags = 0, frame = 0;
1059 if ((vma->vm_flags & VM_SOFTDIRTY) || pmd_soft_dirty(pmd))
1060 flags |= PM_SOFT_DIRTY;
1063 * Currently pmd for thp is always present because thp
1064 * can not be swapped-out, migrated, or HWPOISONed
1065 * (split in such cases instead.)
1066 * This if-check is just to prepare for future implementation.
1068 if (pmd_present(pmd)) {
1069 flags |= PM_PRESENT;
1071 frame = pmd_pfn(pmd) +
1072 ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1075 for (; addr != end; addr += PAGE_SIZE) {
1076 pagemap_entry_t pme = make_pme(frame, flags);
1078 err = add_to_pagemap(addr, &pme, pm);
1081 if (pm->show_pfn && (flags & PM_PRESENT))
1088 if (pmd_trans_unstable(pmdp))
1090 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1093 * We can assume that @vma always points to a valid one and @end never
1094 * goes beyond vma->vm_end.
1096 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl);
1097 for (; addr < end; pte++, addr += PAGE_SIZE) {
1098 pagemap_entry_t pme;
1100 pme = pte_to_pagemap_entry(pm, vma, addr, *pte);
1101 err = add_to_pagemap(addr, &pme, pm);
1105 pte_unmap_unlock(orig_pte, ptl);
1112 #ifdef CONFIG_HUGETLB_PAGE
1113 /* This function walks within one hugetlb entry in the single call */
1114 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask,
1115 unsigned long addr, unsigned long end,
1116 struct mm_walk *walk)
1118 struct pagemapread *pm = walk->private;
1119 struct vm_area_struct *vma = walk->vma;
1120 u64 flags = 0, frame = 0;
1124 if (vma->vm_flags & VM_SOFTDIRTY)
1125 flags |= PM_SOFT_DIRTY;
1127 pte = huge_ptep_get(ptep);
1128 if (pte_present(pte)) {
1129 struct page *page = pte_page(pte);
1131 if (!PageAnon(page))
1134 flags |= PM_PRESENT;
1136 frame = pte_pfn(pte) +
1137 ((addr & ~hmask) >> PAGE_SHIFT);
1140 for (; addr != end; addr += PAGE_SIZE) {
1141 pagemap_entry_t pme = make_pme(frame, flags);
1143 err = add_to_pagemap(addr, &pme, pm);
1146 if (pm->show_pfn && (flags & PM_PRESENT))
1154 #endif /* HUGETLB_PAGE */
1157 * /proc/pid/pagemap - an array mapping virtual pages to pfns
1159 * For each page in the address space, this file contains one 64-bit entry
1160 * consisting of the following:
1162 * Bits 0-54 page frame number (PFN) if present
1163 * Bits 0-4 swap type if swapped
1164 * Bits 5-54 swap offset if swapped
1165 * Bit 55 pte is soft-dirty (see Documentation/vm/soft-dirty.txt)
1167 * Bit 61 page is file-page or shared-anon
1168 * Bit 62 page swapped
1169 * Bit 63 page present
1171 * If the page is not present but in swap, then the PFN contains an
1172 * encoding of the swap file number and the page's offset into the
1173 * swap. Unmapped pages return a null PFN. This allows determining
1174 * precisely which pages are mapped (or in swap) and comparing mapped
1175 * pages between processes.
1177 * Efficient users of this interface will use /proc/pid/maps to
1178 * determine which areas of memory are actually mapped and llseek to
1179 * skip over unmapped regions.
1181 static ssize_t pagemap_read(struct file *file, char __user *buf,
1182 size_t count, loff_t *ppos)
1184 struct mm_struct *mm = file->private_data;
1185 struct pagemapread pm;
1186 struct mm_walk pagemap_walk = {};
1188 unsigned long svpfn;
1189 unsigned long start_vaddr;
1190 unsigned long end_vaddr;
1191 int ret = 0, copied = 0;
1193 if (!mm || !atomic_inc_not_zero(&mm->mm_users))
1197 /* file position must be aligned */
1198 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
1205 /* do not disclose physical addresses: attack vector */
1206 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN);
1208 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
1209 pm.buffer = kmalloc(pm.len * PM_ENTRY_BYTES, GFP_TEMPORARY);
1214 pagemap_walk.pmd_entry = pagemap_pmd_range;
1215 pagemap_walk.pte_hole = pagemap_pte_hole;
1216 #ifdef CONFIG_HUGETLB_PAGE
1217 pagemap_walk.hugetlb_entry = pagemap_hugetlb_range;
1219 pagemap_walk.mm = mm;
1220 pagemap_walk.private = ±
1223 svpfn = src / PM_ENTRY_BYTES;
1224 start_vaddr = svpfn << PAGE_SHIFT;
1225 end_vaddr = mm->task_size;
1227 /* watch out for wraparound */
1228 if (svpfn > mm->task_size >> PAGE_SHIFT)
1229 start_vaddr = end_vaddr;
1232 * The odds are that this will stop walking way
1233 * before end_vaddr, because the length of the
1234 * user buffer is tracked in "pm", and the walk
1235 * will stop when we hit the end of the buffer.
1238 while (count && (start_vaddr < end_vaddr)) {
1243 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
1245 if (end < start_vaddr || end > end_vaddr)
1247 down_read(&mm->mmap_sem);
1248 ret = walk_page_range(start_vaddr, end, &pagemap_walk);
1249 up_read(&mm->mmap_sem);
1252 len = min(count, PM_ENTRY_BYTES * pm.pos);
1253 if (copy_to_user(buf, pm.buffer, len)) {
1262 if (!ret || ret == PM_END_OF_BUFFER)
1273 static int pagemap_open(struct inode *inode, struct file *file)
1275 struct mm_struct *mm;
1277 mm = proc_mem_open(inode, PTRACE_MODE_READ);
1280 file->private_data = mm;
1284 static int pagemap_release(struct inode *inode, struct file *file)
1286 struct mm_struct *mm = file->private_data;
1293 const struct file_operations proc_pagemap_operations = {
1294 .llseek = mem_lseek, /* borrow this */
1295 .read = pagemap_read,
1296 .open = pagemap_open,
1297 .release = pagemap_release,
1299 #endif /* CONFIG_PROC_PAGE_MONITOR */
1304 unsigned long pages;
1306 unsigned long active;
1307 unsigned long writeback;
1308 unsigned long mapcount_max;
1309 unsigned long dirty;
1310 unsigned long swapcache;
1311 unsigned long node[MAX_NUMNODES];
1314 struct numa_maps_private {
1315 struct proc_maps_private proc_maps;
1316 struct numa_maps md;
1319 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
1320 unsigned long nr_pages)
1322 int count = page_mapcount(page);
1324 md->pages += nr_pages;
1325 if (pte_dirty || PageDirty(page))
1326 md->dirty += nr_pages;
1328 if (PageSwapCache(page))
1329 md->swapcache += nr_pages;
1331 if (PageActive(page) || PageUnevictable(page))
1332 md->active += nr_pages;
1334 if (PageWriteback(page))
1335 md->writeback += nr_pages;
1338 md->anon += nr_pages;
1340 if (count > md->mapcount_max)
1341 md->mapcount_max = count;
1343 md->node[page_to_nid(page)] += nr_pages;
1346 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
1352 if (!pte_present(pte))
1355 page = vm_normal_page(vma, addr, pte);
1359 if (PageReserved(page))
1362 nid = page_to_nid(page);
1363 if (!node_isset(nid, node_states[N_MEMORY]))
1369 static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
1370 unsigned long end, struct mm_walk *walk)
1372 struct numa_maps *md = walk->private;
1373 struct vm_area_struct *vma = walk->vma;
1378 if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
1379 pte_t huge_pte = *(pte_t *)pmd;
1382 page = can_gather_numa_stats(huge_pte, vma, addr);
1384 gather_stats(page, md, pte_dirty(huge_pte),
1385 HPAGE_PMD_SIZE/PAGE_SIZE);
1390 if (pmd_trans_unstable(pmd))
1392 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
1394 struct page *page = can_gather_numa_stats(*pte, vma, addr);
1397 gather_stats(page, md, pte_dirty(*pte), 1);
1399 } while (pte++, addr += PAGE_SIZE, addr != end);
1400 pte_unmap_unlock(orig_pte, ptl);
1403 #ifdef CONFIG_HUGETLB_PAGE
1404 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1405 unsigned long addr, unsigned long end, struct mm_walk *walk)
1407 struct numa_maps *md;
1410 if (!pte_present(*pte))
1413 page = pte_page(*pte);
1418 gather_stats(page, md, pte_dirty(*pte), 1);
1423 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1424 unsigned long addr, unsigned long end, struct mm_walk *walk)
1431 * Display pages allocated per node and memory policy via /proc.
1433 static int show_numa_map(struct seq_file *m, void *v, int is_pid)
1435 struct numa_maps_private *numa_priv = m->private;
1436 struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
1437 struct vm_area_struct *vma = v;
1438 struct numa_maps *md = &numa_priv->md;
1439 struct file *file = vma->vm_file;
1440 struct mm_struct *mm = vma->vm_mm;
1441 struct mm_walk walk = {
1442 .hugetlb_entry = gather_hugetlb_stats,
1443 .pmd_entry = gather_pte_stats,
1447 struct mempolicy *pol;
1454 /* Ensure we start with an empty set of numa_maps statistics. */
1455 memset(md, 0, sizeof(*md));
1457 pol = __get_vma_policy(vma, vma->vm_start);
1459 mpol_to_str(buffer, sizeof(buffer), pol);
1462 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy);
1465 seq_printf(m, "%08lx %s", vma->vm_start, buffer);
1468 seq_puts(m, " file=");
1469 seq_file_path(m, file, "\n\t= ");
1470 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1471 seq_puts(m, " heap");
1473 pid_t tid = pid_of_stack(proc_priv, vma, is_pid);
1476 * Thread stack in /proc/PID/task/TID/maps or
1477 * the main process stack.
1479 if (!is_pid || (vma->vm_start <= mm->start_stack &&
1480 vma->vm_end >= mm->start_stack))
1481 seq_puts(m, " stack");
1483 seq_printf(m, " stack:%d", tid);
1487 if (is_vm_hugetlb_page(vma))
1488 seq_puts(m, " huge");
1490 /* mmap_sem is held by m_start */
1491 walk_page_vma(vma, &walk);
1497 seq_printf(m, " anon=%lu", md->anon);
1500 seq_printf(m, " dirty=%lu", md->dirty);
1502 if (md->pages != md->anon && md->pages != md->dirty)
1503 seq_printf(m, " mapped=%lu", md->pages);
1505 if (md->mapcount_max > 1)
1506 seq_printf(m, " mapmax=%lu", md->mapcount_max);
1509 seq_printf(m, " swapcache=%lu", md->swapcache);
1511 if (md->active < md->pages && !is_vm_hugetlb_page(vma))
1512 seq_printf(m, " active=%lu", md->active);
1515 seq_printf(m, " writeback=%lu", md->writeback);
1517 for_each_node_state(nid, N_MEMORY)
1519 seq_printf(m, " N%d=%lu", nid, md->node[nid]);
1521 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10);
1524 m_cache_vma(m, vma);
1528 static int show_pid_numa_map(struct seq_file *m, void *v)
1530 return show_numa_map(m, v, 1);
1533 static int show_tid_numa_map(struct seq_file *m, void *v)
1535 return show_numa_map(m, v, 0);
1538 static const struct seq_operations proc_pid_numa_maps_op = {
1542 .show = show_pid_numa_map,
1545 static const struct seq_operations proc_tid_numa_maps_op = {
1549 .show = show_tid_numa_map,
1552 static int numa_maps_open(struct inode *inode, struct file *file,
1553 const struct seq_operations *ops)
1555 return proc_maps_open(inode, file, ops,
1556 sizeof(struct numa_maps_private));
1559 static int pid_numa_maps_open(struct inode *inode, struct file *file)
1561 return numa_maps_open(inode, file, &proc_pid_numa_maps_op);
1564 static int tid_numa_maps_open(struct inode *inode, struct file *file)
1566 return numa_maps_open(inode, file, &proc_tid_numa_maps_op);
1569 const struct file_operations proc_pid_numa_maps_operations = {
1570 .open = pid_numa_maps_open,
1572 .llseek = seq_lseek,
1573 .release = proc_map_release,
1576 const struct file_operations proc_tid_numa_maps_operations = {
1577 .open = tid_numa_maps_open,
1579 .llseek = seq_lseek,
1580 .release = proc_map_release,
1582 #endif /* CONFIG_NUMA */