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>
16 #include <linux/page_idle.h>
19 #include <asm/uaccess.h>
20 #include <asm/tlbflush.h>
23 void task_mem(struct seq_file *m, struct mm_struct *mm)
25 unsigned long data, text, lib, swap, ptes, pmds;
26 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
29 * Note: to minimize their overhead, mm maintains hiwater_vm and
30 * hiwater_rss only when about to *lower* total_vm or rss. Any
31 * collector of these hiwater stats must therefore get total_vm
32 * and rss too, which will usually be the higher. Barriers? not
33 * worth the effort, such snapshots can always be inconsistent.
35 hiwater_vm = total_vm = mm->total_vm;
36 if (hiwater_vm < mm->hiwater_vm)
37 hiwater_vm = mm->hiwater_vm;
38 hiwater_rss = total_rss = get_mm_rss(mm);
39 if (hiwater_rss < mm->hiwater_rss)
40 hiwater_rss = mm->hiwater_rss;
42 data = mm->total_vm - mm->shared_vm - mm->stack_vm;
43 text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10;
44 lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text;
45 swap = get_mm_counter(mm, MM_SWAPENTS);
46 ptes = PTRS_PER_PTE * sizeof(pte_t) * atomic_long_read(&mm->nr_ptes);
47 pmds = PTRS_PER_PMD * sizeof(pmd_t) * mm_nr_pmds(mm);
62 hiwater_vm << (PAGE_SHIFT-10),
63 total_vm << (PAGE_SHIFT-10),
64 mm->locked_vm << (PAGE_SHIFT-10),
65 mm->pinned_vm << (PAGE_SHIFT-10),
66 hiwater_rss << (PAGE_SHIFT-10),
67 total_rss << (PAGE_SHIFT-10),
68 data << (PAGE_SHIFT-10),
69 mm->stack_vm << (PAGE_SHIFT-10), text, lib,
72 swap << (PAGE_SHIFT-10));
75 unsigned long task_vsize(struct mm_struct *mm)
77 return PAGE_SIZE * mm->total_vm;
80 unsigned long task_statm(struct mm_struct *mm,
81 unsigned long *shared, unsigned long *text,
82 unsigned long *data, unsigned long *resident)
84 *shared = get_mm_counter(mm, MM_FILEPAGES);
85 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
87 *data = mm->total_vm - mm->shared_vm;
88 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
94 * Save get_task_policy() for show_numa_map().
96 static void hold_task_mempolicy(struct proc_maps_private *priv)
98 struct task_struct *task = priv->task;
101 priv->task_mempolicy = get_task_policy(task);
102 mpol_get(priv->task_mempolicy);
105 static void release_task_mempolicy(struct proc_maps_private *priv)
107 mpol_put(priv->task_mempolicy);
110 static void hold_task_mempolicy(struct proc_maps_private *priv)
113 static void release_task_mempolicy(struct proc_maps_private *priv)
118 static void vma_stop(struct proc_maps_private *priv)
120 struct mm_struct *mm = priv->mm;
122 release_task_mempolicy(priv);
123 up_read(&mm->mmap_sem);
127 static struct vm_area_struct *
128 m_next_vma(struct proc_maps_private *priv, struct vm_area_struct *vma)
130 if (vma == priv->tail_vma)
132 return vma->vm_next ?: priv->tail_vma;
135 static void m_cache_vma(struct seq_file *m, struct vm_area_struct *vma)
137 if (m->count < m->size) /* vma is copied successfully */
138 m->version = m_next_vma(m->private, vma) ? vma->vm_start : -1UL;
141 static void *m_start(struct seq_file *m, loff_t *ppos)
143 struct proc_maps_private *priv = m->private;
144 unsigned long last_addr = m->version;
145 struct mm_struct *mm;
146 struct vm_area_struct *vma;
147 unsigned int pos = *ppos;
149 /* See m_cache_vma(). Zero at the start or after lseek. */
150 if (last_addr == -1UL)
153 priv->task = get_proc_task(priv->inode);
155 return ERR_PTR(-ESRCH);
158 if (!mm || !atomic_inc_not_zero(&mm->mm_users))
161 down_read(&mm->mmap_sem);
162 hold_task_mempolicy(priv);
163 priv->tail_vma = get_gate_vma(mm);
166 vma = find_vma(mm, last_addr);
167 if (vma && (vma = m_next_vma(priv, vma)))
172 if (pos < mm->map_count) {
173 for (vma = mm->mmap; pos; pos--) {
174 m->version = vma->vm_start;
180 /* we do not bother to update m->version in this case */
181 if (pos == mm->map_count && priv->tail_vma)
182 return priv->tail_vma;
188 static void *m_next(struct seq_file *m, void *v, loff_t *pos)
190 struct proc_maps_private *priv = m->private;
191 struct vm_area_struct *next;
194 next = m_next_vma(priv, v);
200 static void m_stop(struct seq_file *m, void *v)
202 struct proc_maps_private *priv = m->private;
204 if (!IS_ERR_OR_NULL(v))
207 put_task_struct(priv->task);
212 static int proc_maps_open(struct inode *inode, struct file *file,
213 const struct seq_operations *ops, int psize)
215 struct proc_maps_private *priv = __seq_open_private(file, ops, psize);
221 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
222 if (IS_ERR(priv->mm)) {
223 int err = PTR_ERR(priv->mm);
225 seq_release_private(inode, file);
232 static int proc_map_release(struct inode *inode, struct file *file)
234 struct seq_file *seq = file->private_data;
235 struct proc_maps_private *priv = seq->private;
240 return seq_release_private(inode, file);
243 static int do_maps_open(struct inode *inode, struct file *file,
244 const struct seq_operations *ops)
246 return proc_maps_open(inode, file, ops,
247 sizeof(struct proc_maps_private));
250 static pid_t pid_of_stack(struct proc_maps_private *priv,
251 struct vm_area_struct *vma, bool is_pid)
253 struct inode *inode = priv->inode;
254 struct task_struct *task;
258 task = pid_task(proc_pid(inode), PIDTYPE_PID);
260 task = task_of_stack(task, vma, is_pid);
262 ret = task_pid_nr_ns(task, inode->i_sb->s_fs_info);
270 show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid)
272 struct mm_struct *mm = vma->vm_mm;
273 struct file *file = vma->vm_file;
274 struct proc_maps_private *priv = m->private;
275 vm_flags_t flags = vma->vm_flags;
276 unsigned long ino = 0;
277 unsigned long long pgoff = 0;
278 unsigned long start, end;
280 const char *name = NULL;
283 struct inode *inode = file_inode(vma->vm_file);
284 dev = inode->i_sb->s_dev;
286 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
289 /* We don't show the stack guard page in /proc/maps */
290 start = vma->vm_start;
291 if (stack_guard_page_start(vma, start))
294 if (stack_guard_page_end(vma, end))
297 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
298 seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu ",
301 flags & VM_READ ? 'r' : '-',
302 flags & VM_WRITE ? 'w' : '-',
303 flags & VM_EXEC ? 'x' : '-',
304 flags & VM_MAYSHARE ? 's' : 'p',
306 MAJOR(dev), MINOR(dev), ino);
309 * Print the dentry name for named mappings, and a
310 * special [heap] marker for the heap:
314 seq_file_path(m, file, "\n");
318 if (vma->vm_ops && vma->vm_ops->name) {
319 name = vma->vm_ops->name(vma);
324 name = arch_vma_name(vma);
333 if (vma->vm_start <= mm->brk &&
334 vma->vm_end >= mm->start_brk) {
339 tid = pid_of_stack(priv, vma, is_pid);
342 * Thread stack in /proc/PID/task/TID/maps or
343 * the main process stack.
345 if (!is_pid || (vma->vm_start <= mm->start_stack &&
346 vma->vm_end >= mm->start_stack)) {
349 /* Thread stack in /proc/PID/maps */
351 seq_printf(m, "[stack:%d]", tid);
364 static int show_map(struct seq_file *m, void *v, int is_pid)
366 show_map_vma(m, v, is_pid);
371 static int show_pid_map(struct seq_file *m, void *v)
373 return show_map(m, v, 1);
376 static int show_tid_map(struct seq_file *m, void *v)
378 return show_map(m, v, 0);
381 static const struct seq_operations proc_pid_maps_op = {
388 static const struct seq_operations proc_tid_maps_op = {
395 static int pid_maps_open(struct inode *inode, struct file *file)
397 return do_maps_open(inode, file, &proc_pid_maps_op);
400 static int tid_maps_open(struct inode *inode, struct file *file)
402 return do_maps_open(inode, file, &proc_tid_maps_op);
405 const struct file_operations proc_pid_maps_operations = {
406 .open = pid_maps_open,
409 .release = proc_map_release,
412 const struct file_operations proc_tid_maps_operations = {
413 .open = tid_maps_open,
416 .release = proc_map_release,
420 * Proportional Set Size(PSS): my share of RSS.
422 * PSS of a process is the count of pages it has in memory, where each
423 * page is divided by the number of processes sharing it. So if a
424 * process has 1000 pages all to itself, and 1000 shared with one other
425 * process, its PSS will be 1500.
427 * To keep (accumulated) division errors low, we adopt a 64bit
428 * fixed-point pss counter to minimize division errors. So (pss >>
429 * PSS_SHIFT) would be the real byte count.
431 * A shift of 12 before division means (assuming 4K page size):
432 * - 1M 3-user-pages add up to 8KB errors;
433 * - supports mapcount up to 2^24, or 16M;
434 * - supports PSS up to 2^52 bytes, or 4PB.
438 #ifdef CONFIG_PROC_PAGE_MONITOR
439 struct mem_size_stats {
440 unsigned long resident;
441 unsigned long shared_clean;
442 unsigned long shared_dirty;
443 unsigned long private_clean;
444 unsigned long private_dirty;
445 unsigned long referenced;
446 unsigned long anonymous;
447 unsigned long anonymous_thp;
453 static void smaps_account(struct mem_size_stats *mss, struct page *page,
454 unsigned long size, bool young, bool dirty)
459 mss->anonymous += size;
461 mss->resident += size;
462 /* Accumulate the size in pages that have been accessed. */
463 if (young || page_is_young(page) || PageReferenced(page))
464 mss->referenced += size;
465 mapcount = page_mapcount(page);
469 if (dirty || PageDirty(page))
470 mss->shared_dirty += size;
472 mss->shared_clean += size;
473 pss_delta = (u64)size << PSS_SHIFT;
474 do_div(pss_delta, mapcount);
475 mss->pss += pss_delta;
477 if (dirty || PageDirty(page))
478 mss->private_dirty += size;
480 mss->private_clean += size;
481 mss->pss += (u64)size << PSS_SHIFT;
485 static void smaps_pte_entry(pte_t *pte, unsigned long addr,
486 struct mm_walk *walk)
488 struct mem_size_stats *mss = walk->private;
489 struct vm_area_struct *vma = walk->vma;
490 struct page *page = NULL;
492 if (pte_present(*pte)) {
493 page = vm_normal_page(vma, addr, *pte);
494 } else if (is_swap_pte(*pte)) {
495 swp_entry_t swpent = pte_to_swp_entry(*pte);
497 if (!non_swap_entry(swpent)) {
500 mss->swap += PAGE_SIZE;
501 mapcount = swp_swapcount(swpent);
503 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT;
505 do_div(pss_delta, mapcount);
506 mss->swap_pss += pss_delta;
508 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT;
510 } else if (is_migration_entry(swpent))
511 page = migration_entry_to_page(swpent);
516 smaps_account(mss, page, PAGE_SIZE, pte_young(*pte), pte_dirty(*pte));
519 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
520 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
521 struct mm_walk *walk)
523 struct mem_size_stats *mss = walk->private;
524 struct vm_area_struct *vma = walk->vma;
527 /* FOLL_DUMP will return -EFAULT on huge zero page */
528 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
529 if (IS_ERR_OR_NULL(page))
531 mss->anonymous_thp += HPAGE_PMD_SIZE;
532 smaps_account(mss, page, HPAGE_PMD_SIZE,
533 pmd_young(*pmd), pmd_dirty(*pmd));
536 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
537 struct mm_walk *walk)
542 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
543 struct mm_walk *walk)
545 struct vm_area_struct *vma = walk->vma;
549 if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
550 smaps_pmd_entry(pmd, addr, walk);
555 if (pmd_trans_unstable(pmd))
558 * The mmap_sem held all the way back in m_start() is what
559 * keeps khugepaged out of here and from collapsing things
562 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
563 for (; addr != end; pte++, addr += PAGE_SIZE)
564 smaps_pte_entry(pte, addr, walk);
565 pte_unmap_unlock(pte - 1, ptl);
570 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
573 * Don't forget to update Documentation/ on changes.
575 static const char mnemonics[BITS_PER_LONG][2] = {
577 * In case if we meet a flag we don't know about.
579 [0 ... (BITS_PER_LONG-1)] = "??",
581 [ilog2(VM_READ)] = "rd",
582 [ilog2(VM_WRITE)] = "wr",
583 [ilog2(VM_EXEC)] = "ex",
584 [ilog2(VM_SHARED)] = "sh",
585 [ilog2(VM_MAYREAD)] = "mr",
586 [ilog2(VM_MAYWRITE)] = "mw",
587 [ilog2(VM_MAYEXEC)] = "me",
588 [ilog2(VM_MAYSHARE)] = "ms",
589 [ilog2(VM_GROWSDOWN)] = "gd",
590 [ilog2(VM_PFNMAP)] = "pf",
591 [ilog2(VM_DENYWRITE)] = "dw",
592 #ifdef CONFIG_X86_INTEL_MPX
593 [ilog2(VM_MPX)] = "mp",
595 [ilog2(VM_LOCKED)] = "lo",
596 [ilog2(VM_IO)] = "io",
597 [ilog2(VM_SEQ_READ)] = "sr",
598 [ilog2(VM_RAND_READ)] = "rr",
599 [ilog2(VM_DONTCOPY)] = "dc",
600 [ilog2(VM_DONTEXPAND)] = "de",
601 [ilog2(VM_ACCOUNT)] = "ac",
602 [ilog2(VM_NORESERVE)] = "nr",
603 [ilog2(VM_HUGETLB)] = "ht",
604 [ilog2(VM_ARCH_1)] = "ar",
605 [ilog2(VM_DONTDUMP)] = "dd",
606 #ifdef CONFIG_MEM_SOFT_DIRTY
607 [ilog2(VM_SOFTDIRTY)] = "sd",
609 [ilog2(VM_MIXEDMAP)] = "mm",
610 [ilog2(VM_HUGEPAGE)] = "hg",
611 [ilog2(VM_NOHUGEPAGE)] = "nh",
612 [ilog2(VM_MERGEABLE)] = "mg",
613 [ilog2(VM_UFFD_MISSING)]= "um",
614 [ilog2(VM_UFFD_WP)] = "uw",
618 seq_puts(m, "VmFlags: ");
619 for (i = 0; i < BITS_PER_LONG; i++) {
620 if (vma->vm_flags & (1UL << i)) {
621 seq_printf(m, "%c%c ",
622 mnemonics[i][0], mnemonics[i][1]);
628 static int show_smap(struct seq_file *m, void *v, int is_pid)
630 struct vm_area_struct *vma = v;
631 struct mem_size_stats mss;
632 struct mm_walk smaps_walk = {
633 .pmd_entry = smaps_pte_range,
638 memset(&mss, 0, sizeof mss);
639 /* mmap_sem is held in m_start */
640 walk_page_vma(vma, &smaps_walk);
642 show_map_vma(m, vma, is_pid);
648 "Shared_Clean: %8lu kB\n"
649 "Shared_Dirty: %8lu kB\n"
650 "Private_Clean: %8lu kB\n"
651 "Private_Dirty: %8lu kB\n"
652 "Referenced: %8lu kB\n"
653 "Anonymous: %8lu kB\n"
654 "AnonHugePages: %8lu kB\n"
657 "KernelPageSize: %8lu kB\n"
658 "MMUPageSize: %8lu kB\n"
660 (vma->vm_end - vma->vm_start) >> 10,
662 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)),
663 mss.shared_clean >> 10,
664 mss.shared_dirty >> 10,
665 mss.private_clean >> 10,
666 mss.private_dirty >> 10,
667 mss.referenced >> 10,
669 mss.anonymous_thp >> 10,
671 (unsigned long)(mss.swap_pss >> (10 + PSS_SHIFT)),
672 vma_kernel_pagesize(vma) >> 10,
673 vma_mmu_pagesize(vma) >> 10,
674 (vma->vm_flags & VM_LOCKED) ?
675 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0);
677 show_smap_vma_flags(m, vma);
682 static int show_pid_smap(struct seq_file *m, void *v)
684 return show_smap(m, v, 1);
687 static int show_tid_smap(struct seq_file *m, void *v)
689 return show_smap(m, v, 0);
692 static const struct seq_operations proc_pid_smaps_op = {
696 .show = show_pid_smap
699 static const struct seq_operations proc_tid_smaps_op = {
703 .show = show_tid_smap
706 static int pid_smaps_open(struct inode *inode, struct file *file)
708 return do_maps_open(inode, file, &proc_pid_smaps_op);
711 static int tid_smaps_open(struct inode *inode, struct file *file)
713 return do_maps_open(inode, file, &proc_tid_smaps_op);
716 const struct file_operations proc_pid_smaps_operations = {
717 .open = pid_smaps_open,
720 .release = proc_map_release,
723 const struct file_operations proc_tid_smaps_operations = {
724 .open = tid_smaps_open,
727 .release = proc_map_release,
730 enum clear_refs_types {
734 CLEAR_REFS_SOFT_DIRTY,
735 CLEAR_REFS_MM_HIWATER_RSS,
739 struct clear_refs_private {
740 enum clear_refs_types type;
743 #ifdef CONFIG_MEM_SOFT_DIRTY
744 static inline void clear_soft_dirty(struct vm_area_struct *vma,
745 unsigned long addr, pte_t *pte)
748 * The soft-dirty tracker uses #PF-s to catch writes
749 * to pages, so write-protect the pte as well. See the
750 * Documentation/vm/soft-dirty.txt for full description
751 * of how soft-dirty works.
755 if (pte_present(ptent)) {
756 ptent = pte_wrprotect(ptent);
757 ptent = pte_clear_soft_dirty(ptent);
758 } else if (is_swap_pte(ptent)) {
759 ptent = pte_swp_clear_soft_dirty(ptent);
762 set_pte_at(vma->vm_mm, addr, pte, ptent);
765 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
766 unsigned long addr, pmd_t *pmdp)
770 pmd = pmd_wrprotect(pmd);
771 pmd = pmd_clear_soft_dirty(pmd);
773 if (vma->vm_flags & VM_SOFTDIRTY)
774 vma->vm_flags &= ~VM_SOFTDIRTY;
776 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
781 static inline void clear_soft_dirty(struct vm_area_struct *vma,
782 unsigned long addr, pte_t *pte)
786 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
787 unsigned long addr, pmd_t *pmdp)
792 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
793 unsigned long end, struct mm_walk *walk)
795 struct clear_refs_private *cp = walk->private;
796 struct vm_area_struct *vma = walk->vma;
801 if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
802 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
803 clear_soft_dirty_pmd(vma, addr, pmd);
807 page = pmd_page(*pmd);
809 /* Clear accessed and referenced bits. */
810 pmdp_test_and_clear_young(vma, addr, pmd);
811 test_and_clear_page_young(page);
812 ClearPageReferenced(page);
818 if (pmd_trans_unstable(pmd))
821 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
822 for (; addr != end; pte++, addr += PAGE_SIZE) {
825 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
826 clear_soft_dirty(vma, addr, pte);
830 if (!pte_present(ptent))
833 page = vm_normal_page(vma, addr, ptent);
837 /* Clear accessed and referenced bits. */
838 ptep_test_and_clear_young(vma, addr, pte);
839 test_and_clear_page_young(page);
840 ClearPageReferenced(page);
842 pte_unmap_unlock(pte - 1, ptl);
847 static int clear_refs_test_walk(unsigned long start, unsigned long end,
848 struct mm_walk *walk)
850 struct clear_refs_private *cp = walk->private;
851 struct vm_area_struct *vma = walk->vma;
853 if (vma->vm_flags & VM_PFNMAP)
857 * Writing 1 to /proc/pid/clear_refs affects all pages.
858 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages.
859 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages.
860 * Writing 4 to /proc/pid/clear_refs affects all pages.
862 if (cp->type == CLEAR_REFS_ANON && vma->vm_file)
864 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file)
869 static ssize_t clear_refs_write(struct file *file, const char __user *buf,
870 size_t count, loff_t *ppos)
872 struct task_struct *task;
873 char buffer[PROC_NUMBUF];
874 struct mm_struct *mm;
875 struct vm_area_struct *vma;
876 enum clear_refs_types type;
880 memset(buffer, 0, sizeof(buffer));
881 if (count > sizeof(buffer) - 1)
882 count = sizeof(buffer) - 1;
883 if (copy_from_user(buffer, buf, count))
885 rv = kstrtoint(strstrip(buffer), 10, &itype);
888 type = (enum clear_refs_types)itype;
889 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
892 task = get_proc_task(file_inode(file));
895 mm = get_task_mm(task);
897 struct clear_refs_private cp = {
900 struct mm_walk clear_refs_walk = {
901 .pmd_entry = clear_refs_pte_range,
902 .test_walk = clear_refs_test_walk,
907 if (type == CLEAR_REFS_MM_HIWATER_RSS) {
909 * Writing 5 to /proc/pid/clear_refs resets the peak
910 * resident set size to this mm's current rss value.
912 down_write(&mm->mmap_sem);
913 reset_mm_hiwater_rss(mm);
914 up_write(&mm->mmap_sem);
918 down_read(&mm->mmap_sem);
919 if (type == CLEAR_REFS_SOFT_DIRTY) {
920 for (vma = mm->mmap; vma; vma = vma->vm_next) {
921 if (!(vma->vm_flags & VM_SOFTDIRTY))
923 up_read(&mm->mmap_sem);
924 down_write(&mm->mmap_sem);
925 for (vma = mm->mmap; vma; vma = vma->vm_next) {
926 vma->vm_flags &= ~VM_SOFTDIRTY;
927 vma_set_page_prot(vma);
929 downgrade_write(&mm->mmap_sem);
932 mmu_notifier_invalidate_range_start(mm, 0, -1);
934 walk_page_range(0, ~0UL, &clear_refs_walk);
935 if (type == CLEAR_REFS_SOFT_DIRTY)
936 mmu_notifier_invalidate_range_end(mm, 0, -1);
938 up_read(&mm->mmap_sem);
942 put_task_struct(task);
947 const struct file_operations proc_clear_refs_operations = {
948 .write = clear_refs_write,
949 .llseek = noop_llseek,
957 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */
958 pagemap_entry_t *buffer;
962 #define PAGEMAP_WALK_SIZE (PMD_SIZE)
963 #define PAGEMAP_WALK_MASK (PMD_MASK)
965 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t)
966 #define PM_PFRAME_BITS 55
967 #define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0)
968 #define PM_SOFT_DIRTY BIT_ULL(55)
969 #define PM_MMAP_EXCLUSIVE BIT_ULL(56)
970 #define PM_FILE BIT_ULL(61)
971 #define PM_SWAP BIT_ULL(62)
972 #define PM_PRESENT BIT_ULL(63)
974 #define PM_END_OF_BUFFER 1
976 static inline pagemap_entry_t make_pme(u64 frame, u64 flags)
978 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags };
981 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme,
982 struct pagemapread *pm)
984 pm->buffer[pm->pos++] = *pme;
985 if (pm->pos >= pm->len)
986 return PM_END_OF_BUFFER;
990 static int pagemap_pte_hole(unsigned long start, unsigned long end,
991 struct mm_walk *walk)
993 struct pagemapread *pm = walk->private;
994 unsigned long addr = start;
998 struct vm_area_struct *vma = find_vma(walk->mm, addr);
999 pagemap_entry_t pme = make_pme(0, 0);
1000 /* End of address space hole, which we mark as non-present. */
1001 unsigned long hole_end;
1004 hole_end = min(end, vma->vm_start);
1008 for (; addr < hole_end; addr += PAGE_SIZE) {
1009 err = add_to_pagemap(addr, &pme, pm);
1017 /* Addresses in the VMA. */
1018 if (vma->vm_flags & VM_SOFTDIRTY)
1019 pme = make_pme(0, PM_SOFT_DIRTY);
1020 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) {
1021 err = add_to_pagemap(addr, &pme, pm);
1030 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm,
1031 struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1033 u64 frame = 0, flags = 0;
1034 struct page *page = NULL;
1036 if (pte_present(pte)) {
1038 frame = pte_pfn(pte);
1039 flags |= PM_PRESENT;
1040 page = vm_normal_page(vma, addr, pte);
1041 if (pte_soft_dirty(pte))
1042 flags |= PM_SOFT_DIRTY;
1043 } else if (is_swap_pte(pte)) {
1045 if (pte_swp_soft_dirty(pte))
1046 flags |= PM_SOFT_DIRTY;
1047 entry = pte_to_swp_entry(pte);
1048 frame = swp_type(entry) |
1049 (swp_offset(entry) << MAX_SWAPFILES_SHIFT);
1051 if (is_migration_entry(entry))
1052 page = migration_entry_to_page(entry);
1055 if (page && !PageAnon(page))
1057 if (page && page_mapcount(page) == 1)
1058 flags |= PM_MMAP_EXCLUSIVE;
1059 if (vma->vm_flags & VM_SOFTDIRTY)
1060 flags |= PM_SOFT_DIRTY;
1062 return make_pme(frame, flags);
1065 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
1066 struct mm_walk *walk)
1068 struct vm_area_struct *vma = walk->vma;
1069 struct pagemapread *pm = walk->private;
1071 pte_t *pte, *orig_pte;
1074 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1075 if (pmd_trans_huge_lock(pmdp, vma, &ptl) == 1) {
1076 u64 flags = 0, frame = 0;
1079 if ((vma->vm_flags & VM_SOFTDIRTY) || pmd_soft_dirty(pmd))
1080 flags |= PM_SOFT_DIRTY;
1083 * Currently pmd for thp is always present because thp
1084 * can not be swapped-out, migrated, or HWPOISONed
1085 * (split in such cases instead.)
1086 * This if-check is just to prepare for future implementation.
1088 if (pmd_present(pmd)) {
1089 struct page *page = pmd_page(pmd);
1091 if (page_mapcount(page) == 1)
1092 flags |= PM_MMAP_EXCLUSIVE;
1094 flags |= PM_PRESENT;
1096 frame = pmd_pfn(pmd) +
1097 ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1100 for (; addr != end; addr += PAGE_SIZE) {
1101 pagemap_entry_t pme = make_pme(frame, flags);
1103 err = add_to_pagemap(addr, &pme, pm);
1106 if (pm->show_pfn && (flags & PM_PRESENT))
1113 if (pmd_trans_unstable(pmdp))
1115 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1118 * We can assume that @vma always points to a valid one and @end never
1119 * goes beyond vma->vm_end.
1121 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl);
1122 for (; addr < end; pte++, addr += PAGE_SIZE) {
1123 pagemap_entry_t pme;
1125 pme = pte_to_pagemap_entry(pm, vma, addr, *pte);
1126 err = add_to_pagemap(addr, &pme, pm);
1130 pte_unmap_unlock(orig_pte, ptl);
1137 #ifdef CONFIG_HUGETLB_PAGE
1138 /* This function walks within one hugetlb entry in the single call */
1139 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask,
1140 unsigned long addr, unsigned long end,
1141 struct mm_walk *walk)
1143 struct pagemapread *pm = walk->private;
1144 struct vm_area_struct *vma = walk->vma;
1145 u64 flags = 0, frame = 0;
1149 if (vma->vm_flags & VM_SOFTDIRTY)
1150 flags |= PM_SOFT_DIRTY;
1152 pte = huge_ptep_get(ptep);
1153 if (pte_present(pte)) {
1154 struct page *page = pte_page(pte);
1156 if (!PageAnon(page))
1159 if (page_mapcount(page) == 1)
1160 flags |= PM_MMAP_EXCLUSIVE;
1162 flags |= PM_PRESENT;
1164 frame = pte_pfn(pte) +
1165 ((addr & ~hmask) >> PAGE_SHIFT);
1168 for (; addr != end; addr += PAGE_SIZE) {
1169 pagemap_entry_t pme = make_pme(frame, flags);
1171 err = add_to_pagemap(addr, &pme, pm);
1174 if (pm->show_pfn && (flags & PM_PRESENT))
1182 #endif /* HUGETLB_PAGE */
1185 * /proc/pid/pagemap - an array mapping virtual pages to pfns
1187 * For each page in the address space, this file contains one 64-bit entry
1188 * consisting of the following:
1190 * Bits 0-54 page frame number (PFN) if present
1191 * Bits 0-4 swap type if swapped
1192 * Bits 5-54 swap offset if swapped
1193 * Bit 55 pte is soft-dirty (see Documentation/vm/soft-dirty.txt)
1194 * Bit 56 page exclusively mapped
1196 * Bit 61 page is file-page or shared-anon
1197 * Bit 62 page swapped
1198 * Bit 63 page present
1200 * If the page is not present but in swap, then the PFN contains an
1201 * encoding of the swap file number and the page's offset into the
1202 * swap. Unmapped pages return a null PFN. This allows determining
1203 * precisely which pages are mapped (or in swap) and comparing mapped
1204 * pages between processes.
1206 * Efficient users of this interface will use /proc/pid/maps to
1207 * determine which areas of memory are actually mapped and llseek to
1208 * skip over unmapped regions.
1210 static ssize_t pagemap_read(struct file *file, char __user *buf,
1211 size_t count, loff_t *ppos)
1213 struct mm_struct *mm = file->private_data;
1214 struct pagemapread pm;
1215 struct mm_walk pagemap_walk = {};
1217 unsigned long svpfn;
1218 unsigned long start_vaddr;
1219 unsigned long end_vaddr;
1220 int ret = 0, copied = 0;
1222 if (!mm || !atomic_inc_not_zero(&mm->mm_users))
1226 /* file position must be aligned */
1227 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
1234 /* do not disclose physical addresses: attack vector */
1235 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN);
1237 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
1238 pm.buffer = kmalloc(pm.len * PM_ENTRY_BYTES, GFP_TEMPORARY);
1243 pagemap_walk.pmd_entry = pagemap_pmd_range;
1244 pagemap_walk.pte_hole = pagemap_pte_hole;
1245 #ifdef CONFIG_HUGETLB_PAGE
1246 pagemap_walk.hugetlb_entry = pagemap_hugetlb_range;
1248 pagemap_walk.mm = mm;
1249 pagemap_walk.private = ±
1252 svpfn = src / PM_ENTRY_BYTES;
1253 start_vaddr = svpfn << PAGE_SHIFT;
1254 end_vaddr = mm->task_size;
1256 /* watch out for wraparound */
1257 if (svpfn > mm->task_size >> PAGE_SHIFT)
1258 start_vaddr = end_vaddr;
1261 * The odds are that this will stop walking way
1262 * before end_vaddr, because the length of the
1263 * user buffer is tracked in "pm", and the walk
1264 * will stop when we hit the end of the buffer.
1267 while (count && (start_vaddr < end_vaddr)) {
1272 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
1274 if (end < start_vaddr || end > end_vaddr)
1276 down_read(&mm->mmap_sem);
1277 ret = walk_page_range(start_vaddr, end, &pagemap_walk);
1278 up_read(&mm->mmap_sem);
1281 len = min(count, PM_ENTRY_BYTES * pm.pos);
1282 if (copy_to_user(buf, pm.buffer, len)) {
1291 if (!ret || ret == PM_END_OF_BUFFER)
1302 static int pagemap_open(struct inode *inode, struct file *file)
1304 struct mm_struct *mm;
1306 mm = proc_mem_open(inode, PTRACE_MODE_READ);
1309 file->private_data = mm;
1313 static int pagemap_release(struct inode *inode, struct file *file)
1315 struct mm_struct *mm = file->private_data;
1322 const struct file_operations proc_pagemap_operations = {
1323 .llseek = mem_lseek, /* borrow this */
1324 .read = pagemap_read,
1325 .open = pagemap_open,
1326 .release = pagemap_release,
1328 #endif /* CONFIG_PROC_PAGE_MONITOR */
1333 unsigned long pages;
1335 unsigned long active;
1336 unsigned long writeback;
1337 unsigned long mapcount_max;
1338 unsigned long dirty;
1339 unsigned long swapcache;
1340 unsigned long node[MAX_NUMNODES];
1343 struct numa_maps_private {
1344 struct proc_maps_private proc_maps;
1345 struct numa_maps md;
1348 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
1349 unsigned long nr_pages)
1351 int count = page_mapcount(page);
1353 md->pages += nr_pages;
1354 if (pte_dirty || PageDirty(page))
1355 md->dirty += nr_pages;
1357 if (PageSwapCache(page))
1358 md->swapcache += nr_pages;
1360 if (PageActive(page) || PageUnevictable(page))
1361 md->active += nr_pages;
1363 if (PageWriteback(page))
1364 md->writeback += nr_pages;
1367 md->anon += nr_pages;
1369 if (count > md->mapcount_max)
1370 md->mapcount_max = count;
1372 md->node[page_to_nid(page)] += nr_pages;
1375 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
1381 if (!pte_present(pte))
1384 page = vm_normal_page(vma, addr, pte);
1388 if (PageReserved(page))
1391 nid = page_to_nid(page);
1392 if (!node_isset(nid, node_states[N_MEMORY]))
1398 static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
1399 unsigned long end, struct mm_walk *walk)
1401 struct numa_maps *md = walk->private;
1402 struct vm_area_struct *vma = walk->vma;
1407 if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
1408 pte_t huge_pte = *(pte_t *)pmd;
1411 page = can_gather_numa_stats(huge_pte, vma, addr);
1413 gather_stats(page, md, pte_dirty(huge_pte),
1414 HPAGE_PMD_SIZE/PAGE_SIZE);
1419 if (pmd_trans_unstable(pmd))
1421 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
1423 struct page *page = can_gather_numa_stats(*pte, vma, addr);
1426 gather_stats(page, md, pte_dirty(*pte), 1);
1428 } while (pte++, addr += PAGE_SIZE, addr != end);
1429 pte_unmap_unlock(orig_pte, ptl);
1432 #ifdef CONFIG_HUGETLB_PAGE
1433 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1434 unsigned long addr, unsigned long end, struct mm_walk *walk)
1436 struct numa_maps *md;
1439 if (!pte_present(*pte))
1442 page = pte_page(*pte);
1447 gather_stats(page, md, pte_dirty(*pte), 1);
1452 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1453 unsigned long addr, unsigned long end, struct mm_walk *walk)
1460 * Display pages allocated per node and memory policy via /proc.
1462 static int show_numa_map(struct seq_file *m, void *v, int is_pid)
1464 struct numa_maps_private *numa_priv = m->private;
1465 struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
1466 struct vm_area_struct *vma = v;
1467 struct numa_maps *md = &numa_priv->md;
1468 struct file *file = vma->vm_file;
1469 struct mm_struct *mm = vma->vm_mm;
1470 struct mm_walk walk = {
1471 .hugetlb_entry = gather_hugetlb_stats,
1472 .pmd_entry = gather_pte_stats,
1476 struct mempolicy *pol;
1483 /* Ensure we start with an empty set of numa_maps statistics. */
1484 memset(md, 0, sizeof(*md));
1486 pol = __get_vma_policy(vma, vma->vm_start);
1488 mpol_to_str(buffer, sizeof(buffer), pol);
1491 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy);
1494 seq_printf(m, "%08lx %s", vma->vm_start, buffer);
1497 seq_puts(m, " file=");
1498 seq_file_path(m, file, "\n\t= ");
1499 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1500 seq_puts(m, " heap");
1502 pid_t tid = pid_of_stack(proc_priv, vma, is_pid);
1505 * Thread stack in /proc/PID/task/TID/maps or
1506 * the main process stack.
1508 if (!is_pid || (vma->vm_start <= mm->start_stack &&
1509 vma->vm_end >= mm->start_stack))
1510 seq_puts(m, " stack");
1512 seq_printf(m, " stack:%d", tid);
1516 if (is_vm_hugetlb_page(vma))
1517 seq_puts(m, " huge");
1519 /* mmap_sem is held by m_start */
1520 walk_page_vma(vma, &walk);
1526 seq_printf(m, " anon=%lu", md->anon);
1529 seq_printf(m, " dirty=%lu", md->dirty);
1531 if (md->pages != md->anon && md->pages != md->dirty)
1532 seq_printf(m, " mapped=%lu", md->pages);
1534 if (md->mapcount_max > 1)
1535 seq_printf(m, " mapmax=%lu", md->mapcount_max);
1538 seq_printf(m, " swapcache=%lu", md->swapcache);
1540 if (md->active < md->pages && !is_vm_hugetlb_page(vma))
1541 seq_printf(m, " active=%lu", md->active);
1544 seq_printf(m, " writeback=%lu", md->writeback);
1546 for_each_node_state(nid, N_MEMORY)
1548 seq_printf(m, " N%d=%lu", nid, md->node[nid]);
1550 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10);
1553 m_cache_vma(m, vma);
1557 static int show_pid_numa_map(struct seq_file *m, void *v)
1559 return show_numa_map(m, v, 1);
1562 static int show_tid_numa_map(struct seq_file *m, void *v)
1564 return show_numa_map(m, v, 0);
1567 static const struct seq_operations proc_pid_numa_maps_op = {
1571 .show = show_pid_numa_map,
1574 static const struct seq_operations proc_tid_numa_maps_op = {
1578 .show = show_tid_numa_map,
1581 static int numa_maps_open(struct inode *inode, struct file *file,
1582 const struct seq_operations *ops)
1584 return proc_maps_open(inode, file, ops,
1585 sizeof(struct numa_maps_private));
1588 static int pid_numa_maps_open(struct inode *inode, struct file *file)
1590 return numa_maps_open(inode, file, &proc_pid_numa_maps_op);
1593 static int tid_numa_maps_open(struct inode *inode, struct file *file)
1595 return numa_maps_open(inode, file, &proc_tid_numa_maps_op);
1598 const struct file_operations proc_pid_numa_maps_operations = {
1599 .open = pid_numa_maps_open,
1601 .llseek = seq_lseek,
1602 .release = proc_map_release,
1605 const struct file_operations proc_tid_numa_maps_operations = {
1606 .open = tid_numa_maps_open,
1608 .llseek = seq_lseek,
1609 .release = proc_map_release,
1611 #endif /* CONFIG_NUMA */