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>
17 #include <linux/shmem_fs.h>
20 #include <asm/uaccess.h>
21 #include <asm/tlbflush.h>
24 void task_mem(struct seq_file *m, struct mm_struct *mm)
26 unsigned long text, lib, swap, ptes, pmds, anon, file, shmem;
27 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
29 anon = get_mm_counter(mm, MM_ANONPAGES);
30 file = get_mm_counter(mm, MM_FILEPAGES);
31 shmem = get_mm_counter(mm, MM_SHMEMPAGES);
34 * Note: to minimize their overhead, mm maintains hiwater_vm and
35 * hiwater_rss only when about to *lower* total_vm or rss. Any
36 * collector of these hiwater stats must therefore get total_vm
37 * and rss too, which will usually be the higher. Barriers? not
38 * worth the effort, such snapshots can always be inconsistent.
40 hiwater_vm = total_vm = mm->total_vm;
41 if (hiwater_vm < mm->hiwater_vm)
42 hiwater_vm = mm->hiwater_vm;
43 hiwater_rss = total_rss = anon + file + shmem;
44 if (hiwater_rss < mm->hiwater_rss)
45 hiwater_rss = mm->hiwater_rss;
47 text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10;
48 lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text;
49 swap = get_mm_counter(mm, MM_SWAPENTS);
50 ptes = PTRS_PER_PTE * sizeof(pte_t) * atomic_long_read(&mm->nr_ptes);
51 pmds = PTRS_PER_PMD * sizeof(pmd_t) * mm_nr_pmds(mm);
61 "RssShmem:\t%8lu kB\n"
69 hiwater_vm << (PAGE_SHIFT-10),
70 total_vm << (PAGE_SHIFT-10),
71 mm->locked_vm << (PAGE_SHIFT-10),
72 mm->pinned_vm << (PAGE_SHIFT-10),
73 hiwater_rss << (PAGE_SHIFT-10),
74 total_rss << (PAGE_SHIFT-10),
75 anon << (PAGE_SHIFT-10),
76 file << (PAGE_SHIFT-10),
77 shmem << (PAGE_SHIFT-10),
78 mm->data_vm << (PAGE_SHIFT-10),
79 mm->stack_vm << (PAGE_SHIFT-10), text, lib,
82 swap << (PAGE_SHIFT-10));
83 hugetlb_report_usage(m, mm);
86 unsigned long task_vsize(struct mm_struct *mm)
88 return PAGE_SIZE * mm->total_vm;
91 unsigned long task_statm(struct mm_struct *mm,
92 unsigned long *shared, unsigned long *text,
93 unsigned long *data, unsigned long *resident)
95 *shared = get_mm_counter(mm, MM_FILEPAGES) +
96 get_mm_counter(mm, MM_SHMEMPAGES);
97 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
99 *data = mm->data_vm + mm->stack_vm;
100 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
106 * Save get_task_policy() for show_numa_map().
108 static void hold_task_mempolicy(struct proc_maps_private *priv)
110 struct task_struct *task = priv->task;
113 priv->task_mempolicy = get_task_policy(task);
114 mpol_get(priv->task_mempolicy);
117 static void release_task_mempolicy(struct proc_maps_private *priv)
119 mpol_put(priv->task_mempolicy);
122 static void hold_task_mempolicy(struct proc_maps_private *priv)
125 static void release_task_mempolicy(struct proc_maps_private *priv)
130 static void vma_stop(struct proc_maps_private *priv)
132 struct mm_struct *mm = priv->mm;
134 release_task_mempolicy(priv);
135 up_read(&mm->mmap_sem);
139 static struct vm_area_struct *
140 m_next_vma(struct proc_maps_private *priv, struct vm_area_struct *vma)
142 if (vma == priv->tail_vma)
144 return vma->vm_next ?: priv->tail_vma;
147 static void m_cache_vma(struct seq_file *m, struct vm_area_struct *vma)
149 if (m->count < m->size) /* vma is copied successfully */
150 m->version = m_next_vma(m->private, vma) ? vma->vm_end : -1UL;
153 static void *m_start(struct seq_file *m, loff_t *ppos)
155 struct proc_maps_private *priv = m->private;
156 unsigned long last_addr = m->version;
157 struct mm_struct *mm;
158 struct vm_area_struct *vma;
159 unsigned int pos = *ppos;
161 /* See m_cache_vma(). Zero at the start or after lseek. */
162 if (last_addr == -1UL)
165 priv->task = get_proc_task(priv->inode);
167 return ERR_PTR(-ESRCH);
170 if (!mm || !atomic_inc_not_zero(&mm->mm_users))
173 down_read(&mm->mmap_sem);
174 hold_task_mempolicy(priv);
175 priv->tail_vma = get_gate_vma(mm);
178 vma = find_vma(mm, last_addr - 1);
179 if (vma && vma->vm_start <= last_addr)
180 vma = m_next_vma(priv, vma);
186 if (pos < mm->map_count) {
187 for (vma = mm->mmap; pos; pos--) {
188 m->version = vma->vm_start;
194 /* we do not bother to update m->version in this case */
195 if (pos == mm->map_count && priv->tail_vma)
196 return priv->tail_vma;
202 static void *m_next(struct seq_file *m, void *v, loff_t *pos)
204 struct proc_maps_private *priv = m->private;
205 struct vm_area_struct *next;
208 next = m_next_vma(priv, v);
214 static void m_stop(struct seq_file *m, void *v)
216 struct proc_maps_private *priv = m->private;
218 if (!IS_ERR_OR_NULL(v))
221 put_task_struct(priv->task);
226 static int proc_maps_open(struct inode *inode, struct file *file,
227 const struct seq_operations *ops, int psize)
229 struct proc_maps_private *priv = __seq_open_private(file, ops, psize);
235 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
236 if (IS_ERR(priv->mm)) {
237 int err = PTR_ERR(priv->mm);
239 seq_release_private(inode, file);
246 static int proc_map_release(struct inode *inode, struct file *file)
248 struct seq_file *seq = file->private_data;
249 struct proc_maps_private *priv = seq->private;
254 return seq_release_private(inode, file);
257 static int do_maps_open(struct inode *inode, struct file *file,
258 const struct seq_operations *ops)
260 return proc_maps_open(inode, file, ops,
261 sizeof(struct proc_maps_private));
265 * Indicate if the VMA is a stack for the given task; for
266 * /proc/PID/maps that is the stack of the main task.
268 static int is_stack(struct proc_maps_private *priv,
269 struct vm_area_struct *vma)
272 * We make no effort to guess what a given thread considers to be
273 * its "stack". It's not even well-defined for programs written
276 return vma->vm_start <= vma->vm_mm->start_stack &&
277 vma->vm_end >= vma->vm_mm->start_stack;
281 show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid)
283 struct mm_struct *mm = vma->vm_mm;
284 struct file *file = vma->vm_file;
285 struct proc_maps_private *priv = m->private;
286 vm_flags_t flags = vma->vm_flags;
287 unsigned long ino = 0;
288 unsigned long long pgoff = 0;
289 unsigned long start, end;
291 const char *name = NULL;
294 struct inode *inode = file_inode(vma->vm_file);
295 dev = inode->i_sb->s_dev;
297 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
300 /* We don't show the stack guard page in /proc/maps */
301 start = vma->vm_start;
304 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
305 seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu ",
308 flags & VM_READ ? 'r' : '-',
309 flags & VM_WRITE ? 'w' : '-',
310 flags & VM_EXEC ? 'x' : '-',
311 flags & VM_MAYSHARE ? 's' : 'p',
313 MAJOR(dev), MINOR(dev), ino);
316 * Print the dentry name for named mappings, and a
317 * special [heap] marker for the heap:
321 seq_file_path(m, file, "\n");
325 if (vma->vm_ops && vma->vm_ops->name) {
326 name = vma->vm_ops->name(vma);
331 name = arch_vma_name(vma);
338 if (vma->vm_start <= mm->brk &&
339 vma->vm_end >= mm->start_brk) {
344 if (is_stack(priv, vma))
356 static int show_map(struct seq_file *m, void *v, int is_pid)
358 show_map_vma(m, v, is_pid);
363 static int show_pid_map(struct seq_file *m, void *v)
365 return show_map(m, v, 1);
368 static int show_tid_map(struct seq_file *m, void *v)
370 return show_map(m, v, 0);
373 static const struct seq_operations proc_pid_maps_op = {
380 static const struct seq_operations proc_tid_maps_op = {
387 static int pid_maps_open(struct inode *inode, struct file *file)
389 return do_maps_open(inode, file, &proc_pid_maps_op);
392 static int tid_maps_open(struct inode *inode, struct file *file)
394 return do_maps_open(inode, file, &proc_tid_maps_op);
397 const struct file_operations proc_pid_maps_operations = {
398 .open = pid_maps_open,
401 .release = proc_map_release,
404 const struct file_operations proc_tid_maps_operations = {
405 .open = tid_maps_open,
408 .release = proc_map_release,
412 * Proportional Set Size(PSS): my share of RSS.
414 * PSS of a process is the count of pages it has in memory, where each
415 * page is divided by the number of processes sharing it. So if a
416 * process has 1000 pages all to itself, and 1000 shared with one other
417 * process, its PSS will be 1500.
419 * To keep (accumulated) division errors low, we adopt a 64bit
420 * fixed-point pss counter to minimize division errors. So (pss >>
421 * PSS_SHIFT) would be the real byte count.
423 * A shift of 12 before division means (assuming 4K page size):
424 * - 1M 3-user-pages add up to 8KB errors;
425 * - supports mapcount up to 2^24, or 16M;
426 * - supports PSS up to 2^52 bytes, or 4PB.
430 #ifdef CONFIG_PROC_PAGE_MONITOR
431 struct mem_size_stats {
432 unsigned long resident;
433 unsigned long shared_clean;
434 unsigned long shared_dirty;
435 unsigned long private_clean;
436 unsigned long private_dirty;
437 unsigned long referenced;
438 unsigned long anonymous;
439 unsigned long anonymous_thp;
440 unsigned long shmem_thp;
442 unsigned long shared_hugetlb;
443 unsigned long private_hugetlb;
446 bool check_shmem_swap;
449 static void smaps_account(struct mem_size_stats *mss, struct page *page,
450 bool compound, bool young, bool dirty)
452 int i, nr = compound ? 1 << compound_order(page) : 1;
453 unsigned long size = nr * PAGE_SIZE;
456 mss->anonymous += size;
458 mss->resident += size;
459 /* Accumulate the size in pages that have been accessed. */
460 if (young || page_is_young(page) || PageReferenced(page))
461 mss->referenced += size;
464 * page_count(page) == 1 guarantees the page is mapped exactly once.
465 * If any subpage of the compound page mapped with PTE it would elevate
468 if (page_count(page) == 1) {
469 if (dirty || PageDirty(page))
470 mss->private_dirty += size;
472 mss->private_clean += size;
473 mss->pss += (u64)size << PSS_SHIFT;
477 for (i = 0; i < nr; i++, page++) {
478 int mapcount = page_mapcount(page);
481 if (dirty || PageDirty(page))
482 mss->shared_dirty += PAGE_SIZE;
484 mss->shared_clean += PAGE_SIZE;
485 mss->pss += (PAGE_SIZE << PSS_SHIFT) / mapcount;
487 if (dirty || PageDirty(page))
488 mss->private_dirty += PAGE_SIZE;
490 mss->private_clean += PAGE_SIZE;
491 mss->pss += PAGE_SIZE << PSS_SHIFT;
497 static int smaps_pte_hole(unsigned long addr, unsigned long end,
498 struct mm_walk *walk)
500 struct mem_size_stats *mss = walk->private;
502 mss->swap += shmem_partial_swap_usage(
503 walk->vma->vm_file->f_mapping, addr, end);
509 static void smaps_pte_entry(pte_t *pte, unsigned long addr,
510 struct mm_walk *walk)
512 struct mem_size_stats *mss = walk->private;
513 struct vm_area_struct *vma = walk->vma;
514 struct page *page = NULL;
516 if (pte_present(*pte)) {
517 page = vm_normal_page(vma, addr, *pte);
518 } else if (is_swap_pte(*pte)) {
519 swp_entry_t swpent = pte_to_swp_entry(*pte);
521 if (!non_swap_entry(swpent)) {
524 mss->swap += PAGE_SIZE;
525 mapcount = swp_swapcount(swpent);
527 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT;
529 do_div(pss_delta, mapcount);
530 mss->swap_pss += pss_delta;
532 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT;
534 } else if (is_migration_entry(swpent))
535 page = migration_entry_to_page(swpent);
536 } else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap
537 && pte_none(*pte))) {
538 page = find_get_entry(vma->vm_file->f_mapping,
539 linear_page_index(vma, addr));
543 if (radix_tree_exceptional_entry(page))
544 mss->swap += PAGE_SIZE;
554 smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte));
557 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
558 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
559 struct mm_walk *walk)
561 struct mem_size_stats *mss = walk->private;
562 struct vm_area_struct *vma = walk->vma;
565 /* FOLL_DUMP will return -EFAULT on huge zero page */
566 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
567 if (IS_ERR_OR_NULL(page))
570 mss->anonymous_thp += HPAGE_PMD_SIZE;
571 else if (PageSwapBacked(page))
572 mss->shmem_thp += HPAGE_PMD_SIZE;
573 else if (is_zone_device_page(page))
576 VM_BUG_ON_PAGE(1, page);
577 smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd));
580 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
581 struct mm_walk *walk)
586 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
587 struct mm_walk *walk)
589 struct vm_area_struct *vma = walk->vma;
593 ptl = pmd_trans_huge_lock(pmd, vma);
595 smaps_pmd_entry(pmd, addr, walk);
600 if (pmd_trans_unstable(pmd))
603 * The mmap_sem held all the way back in m_start() is what
604 * keeps khugepaged out of here and from collapsing things
607 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
608 for (; addr != end; pte++, addr += PAGE_SIZE)
609 smaps_pte_entry(pte, addr, walk);
610 pte_unmap_unlock(pte - 1, ptl);
615 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
618 * Don't forget to update Documentation/ on changes.
620 static const char mnemonics[BITS_PER_LONG][2] = {
622 * In case if we meet a flag we don't know about.
624 [0 ... (BITS_PER_LONG-1)] = "??",
626 [ilog2(VM_READ)] = "rd",
627 [ilog2(VM_WRITE)] = "wr",
628 [ilog2(VM_EXEC)] = "ex",
629 [ilog2(VM_SHARED)] = "sh",
630 [ilog2(VM_MAYREAD)] = "mr",
631 [ilog2(VM_MAYWRITE)] = "mw",
632 [ilog2(VM_MAYEXEC)] = "me",
633 [ilog2(VM_MAYSHARE)] = "ms",
634 [ilog2(VM_GROWSDOWN)] = "gd",
635 [ilog2(VM_PFNMAP)] = "pf",
636 [ilog2(VM_DENYWRITE)] = "dw",
637 #ifdef CONFIG_X86_INTEL_MPX
638 [ilog2(VM_MPX)] = "mp",
640 [ilog2(VM_LOCKED)] = "lo",
641 [ilog2(VM_IO)] = "io",
642 [ilog2(VM_SEQ_READ)] = "sr",
643 [ilog2(VM_RAND_READ)] = "rr",
644 [ilog2(VM_DONTCOPY)] = "dc",
645 [ilog2(VM_DONTEXPAND)] = "de",
646 [ilog2(VM_ACCOUNT)] = "ac",
647 [ilog2(VM_NORESERVE)] = "nr",
648 [ilog2(VM_HUGETLB)] = "ht",
649 [ilog2(VM_ARCH_1)] = "ar",
650 [ilog2(VM_DONTDUMP)] = "dd",
651 #ifdef CONFIG_MEM_SOFT_DIRTY
652 [ilog2(VM_SOFTDIRTY)] = "sd",
654 [ilog2(VM_MIXEDMAP)] = "mm",
655 [ilog2(VM_HUGEPAGE)] = "hg",
656 [ilog2(VM_NOHUGEPAGE)] = "nh",
657 [ilog2(VM_MERGEABLE)] = "mg",
658 [ilog2(VM_UFFD_MISSING)]= "um",
659 [ilog2(VM_UFFD_WP)] = "uw",
660 #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
661 /* These come out via ProtectionKey: */
662 [ilog2(VM_PKEY_BIT0)] = "",
663 [ilog2(VM_PKEY_BIT1)] = "",
664 [ilog2(VM_PKEY_BIT2)] = "",
665 [ilog2(VM_PKEY_BIT3)] = "",
670 seq_puts(m, "VmFlags: ");
671 for (i = 0; i < BITS_PER_LONG; i++) {
672 if (!mnemonics[i][0])
674 if (vma->vm_flags & (1UL << i)) {
675 seq_printf(m, "%c%c ",
676 mnemonics[i][0], mnemonics[i][1]);
682 #ifdef CONFIG_HUGETLB_PAGE
683 static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,
684 unsigned long addr, unsigned long end,
685 struct mm_walk *walk)
687 struct mem_size_stats *mss = walk->private;
688 struct vm_area_struct *vma = walk->vma;
689 struct page *page = NULL;
691 if (pte_present(*pte)) {
692 page = vm_normal_page(vma, addr, *pte);
693 } else if (is_swap_pte(*pte)) {
694 swp_entry_t swpent = pte_to_swp_entry(*pte);
696 if (is_migration_entry(swpent))
697 page = migration_entry_to_page(swpent);
700 int mapcount = page_mapcount(page);
703 mss->shared_hugetlb += huge_page_size(hstate_vma(vma));
705 mss->private_hugetlb += huge_page_size(hstate_vma(vma));
709 #endif /* HUGETLB_PAGE */
711 void __weak arch_show_smap(struct seq_file *m, struct vm_area_struct *vma)
715 static int show_smap(struct seq_file *m, void *v, int is_pid)
717 struct vm_area_struct *vma = v;
718 struct mem_size_stats mss;
719 struct mm_walk smaps_walk = {
720 .pmd_entry = smaps_pte_range,
721 #ifdef CONFIG_HUGETLB_PAGE
722 .hugetlb_entry = smaps_hugetlb_range,
728 memset(&mss, 0, sizeof mss);
731 if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) {
733 * For shared or readonly shmem mappings we know that all
734 * swapped out pages belong to the shmem object, and we can
735 * obtain the swap value much more efficiently. For private
736 * writable mappings, we might have COW pages that are
737 * not affected by the parent swapped out pages of the shmem
738 * object, so we have to distinguish them during the page walk.
739 * Unless we know that the shmem object (or the part mapped by
740 * our VMA) has no swapped out pages at all.
742 unsigned long shmem_swapped = shmem_swap_usage(vma);
744 if (!shmem_swapped || (vma->vm_flags & VM_SHARED) ||
745 !(vma->vm_flags & VM_WRITE)) {
746 mss.swap = shmem_swapped;
748 mss.check_shmem_swap = true;
749 smaps_walk.pte_hole = smaps_pte_hole;
754 /* mmap_sem is held in m_start */
755 walk_page_vma(vma, &smaps_walk);
757 show_map_vma(m, vma, is_pid);
763 "Shared_Clean: %8lu kB\n"
764 "Shared_Dirty: %8lu kB\n"
765 "Private_Clean: %8lu kB\n"
766 "Private_Dirty: %8lu kB\n"
767 "Referenced: %8lu kB\n"
768 "Anonymous: %8lu kB\n"
769 "AnonHugePages: %8lu kB\n"
770 "ShmemPmdMapped: %8lu kB\n"
771 "Shared_Hugetlb: %8lu kB\n"
772 "Private_Hugetlb: %7lu kB\n"
775 "KernelPageSize: %8lu kB\n"
776 "MMUPageSize: %8lu kB\n"
778 (vma->vm_end - vma->vm_start) >> 10,
780 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)),
781 mss.shared_clean >> 10,
782 mss.shared_dirty >> 10,
783 mss.private_clean >> 10,
784 mss.private_dirty >> 10,
785 mss.referenced >> 10,
787 mss.anonymous_thp >> 10,
789 mss.shared_hugetlb >> 10,
790 mss.private_hugetlb >> 10,
792 (unsigned long)(mss.swap_pss >> (10 + PSS_SHIFT)),
793 vma_kernel_pagesize(vma) >> 10,
794 vma_mmu_pagesize(vma) >> 10,
795 (vma->vm_flags & VM_LOCKED) ?
796 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0);
798 arch_show_smap(m, vma);
799 show_smap_vma_flags(m, vma);
804 static int show_pid_smap(struct seq_file *m, void *v)
806 return show_smap(m, v, 1);
809 static int show_tid_smap(struct seq_file *m, void *v)
811 return show_smap(m, v, 0);
814 static const struct seq_operations proc_pid_smaps_op = {
818 .show = show_pid_smap
821 static const struct seq_operations proc_tid_smaps_op = {
825 .show = show_tid_smap
828 static int pid_smaps_open(struct inode *inode, struct file *file)
830 return do_maps_open(inode, file, &proc_pid_smaps_op);
833 static int tid_smaps_open(struct inode *inode, struct file *file)
835 return do_maps_open(inode, file, &proc_tid_smaps_op);
838 const struct file_operations proc_pid_smaps_operations = {
839 .open = pid_smaps_open,
842 .release = proc_map_release,
845 const struct file_operations proc_tid_smaps_operations = {
846 .open = tid_smaps_open,
849 .release = proc_map_release,
852 enum clear_refs_types {
856 CLEAR_REFS_SOFT_DIRTY,
857 CLEAR_REFS_MM_HIWATER_RSS,
861 struct clear_refs_private {
862 enum clear_refs_types type;
865 #ifdef CONFIG_MEM_SOFT_DIRTY
866 static inline void clear_soft_dirty(struct vm_area_struct *vma,
867 unsigned long addr, pte_t *pte)
870 * The soft-dirty tracker uses #PF-s to catch writes
871 * to pages, so write-protect the pte as well. See the
872 * Documentation/vm/soft-dirty.txt for full description
873 * of how soft-dirty works.
877 if (pte_present(ptent)) {
878 ptent = ptep_modify_prot_start(vma->vm_mm, addr, pte);
879 ptent = pte_wrprotect(ptent);
880 ptent = pte_clear_soft_dirty(ptent);
881 ptep_modify_prot_commit(vma->vm_mm, addr, pte, ptent);
882 } else if (is_swap_pte(ptent)) {
883 ptent = pte_swp_clear_soft_dirty(ptent);
884 set_pte_at(vma->vm_mm, addr, pte, ptent);
888 static inline void clear_soft_dirty(struct vm_area_struct *vma,
889 unsigned long addr, pte_t *pte)
894 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
895 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
896 unsigned long addr, pmd_t *pmdp)
900 /* See comment in change_huge_pmd() */
901 pmdp_invalidate(vma, addr, pmdp);
902 if (pmd_dirty(*pmdp))
903 pmd = pmd_mkdirty(pmd);
904 if (pmd_young(*pmdp))
905 pmd = pmd_mkyoung(pmd);
907 pmd = pmd_wrprotect(pmd);
908 pmd = pmd_clear_soft_dirty(pmd);
910 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
913 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
914 unsigned long addr, pmd_t *pmdp)
919 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
920 unsigned long end, struct mm_walk *walk)
922 struct clear_refs_private *cp = walk->private;
923 struct vm_area_struct *vma = walk->vma;
928 ptl = pmd_trans_huge_lock(pmd, vma);
930 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
931 clear_soft_dirty_pmd(vma, addr, pmd);
935 page = pmd_page(*pmd);
937 /* Clear accessed and referenced bits. */
938 pmdp_test_and_clear_young(vma, addr, pmd);
939 test_and_clear_page_young(page);
940 ClearPageReferenced(page);
946 if (pmd_trans_unstable(pmd))
949 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
950 for (; addr != end; pte++, addr += PAGE_SIZE) {
953 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
954 clear_soft_dirty(vma, addr, pte);
958 if (!pte_present(ptent))
961 page = vm_normal_page(vma, addr, ptent);
965 /* Clear accessed and referenced bits. */
966 ptep_test_and_clear_young(vma, addr, pte);
967 test_and_clear_page_young(page);
968 ClearPageReferenced(page);
970 pte_unmap_unlock(pte - 1, ptl);
975 static int clear_refs_test_walk(unsigned long start, unsigned long end,
976 struct mm_walk *walk)
978 struct clear_refs_private *cp = walk->private;
979 struct vm_area_struct *vma = walk->vma;
981 if (vma->vm_flags & VM_PFNMAP)
985 * Writing 1 to /proc/pid/clear_refs affects all pages.
986 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages.
987 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages.
988 * Writing 4 to /proc/pid/clear_refs affects all pages.
990 if (cp->type == CLEAR_REFS_ANON && vma->vm_file)
992 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file)
997 static ssize_t clear_refs_write(struct file *file, const char __user *buf,
998 size_t count, loff_t *ppos)
1000 struct task_struct *task;
1001 char buffer[PROC_NUMBUF];
1002 struct mm_struct *mm;
1003 struct vm_area_struct *vma;
1004 enum clear_refs_types type;
1008 memset(buffer, 0, sizeof(buffer));
1009 if (count > sizeof(buffer) - 1)
1010 count = sizeof(buffer) - 1;
1011 if (copy_from_user(buffer, buf, count))
1013 rv = kstrtoint(strstrip(buffer), 10, &itype);
1016 type = (enum clear_refs_types)itype;
1017 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
1020 task = get_proc_task(file_inode(file));
1023 mm = get_task_mm(task);
1025 struct clear_refs_private cp = {
1028 struct mm_walk clear_refs_walk = {
1029 .pmd_entry = clear_refs_pte_range,
1030 .test_walk = clear_refs_test_walk,
1035 if (type == CLEAR_REFS_MM_HIWATER_RSS) {
1036 if (down_write_killable(&mm->mmap_sem)) {
1042 * Writing 5 to /proc/pid/clear_refs resets the peak
1043 * resident set size to this mm's current rss value.
1045 reset_mm_hiwater_rss(mm);
1046 up_write(&mm->mmap_sem);
1050 down_read(&mm->mmap_sem);
1051 if (type == CLEAR_REFS_SOFT_DIRTY) {
1052 for (vma = mm->mmap; vma; vma = vma->vm_next) {
1053 if (!(vma->vm_flags & VM_SOFTDIRTY))
1055 up_read(&mm->mmap_sem);
1056 if (down_write_killable(&mm->mmap_sem)) {
1061 * Avoid to modify vma->vm_flags
1062 * without locked ops while the
1063 * coredump reads the vm_flags.
1065 if (!mmget_still_valid(mm)) {
1067 * Silently return "count"
1068 * like if get_task_mm()
1069 * failed. FIXME: should this
1070 * function have returned
1071 * -ESRCH if get_task_mm()
1073 * get_proc_task() fails?
1075 up_write(&mm->mmap_sem);
1078 for (vma = mm->mmap; vma; vma = vma->vm_next) {
1079 vma->vm_flags &= ~VM_SOFTDIRTY;
1080 vma_set_page_prot(vma);
1082 downgrade_write(&mm->mmap_sem);
1085 mmu_notifier_invalidate_range_start(mm, 0, -1);
1087 walk_page_range(0, mm->highest_vm_end, &clear_refs_walk);
1088 if (type == CLEAR_REFS_SOFT_DIRTY)
1089 mmu_notifier_invalidate_range_end(mm, 0, -1);
1091 up_read(&mm->mmap_sem);
1095 put_task_struct(task);
1100 const struct file_operations proc_clear_refs_operations = {
1101 .write = clear_refs_write,
1102 .llseek = noop_llseek,
1109 struct pagemapread {
1110 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */
1111 pagemap_entry_t *buffer;
1115 #define PAGEMAP_WALK_SIZE (PMD_SIZE)
1116 #define PAGEMAP_WALK_MASK (PMD_MASK)
1118 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t)
1119 #define PM_PFRAME_BITS 55
1120 #define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0)
1121 #define PM_SOFT_DIRTY BIT_ULL(55)
1122 #define PM_MMAP_EXCLUSIVE BIT_ULL(56)
1123 #define PM_FILE BIT_ULL(61)
1124 #define PM_SWAP BIT_ULL(62)
1125 #define PM_PRESENT BIT_ULL(63)
1127 #define PM_END_OF_BUFFER 1
1129 static inline pagemap_entry_t make_pme(u64 frame, u64 flags)
1131 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags };
1134 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme,
1135 struct pagemapread *pm)
1137 pm->buffer[pm->pos++] = *pme;
1138 if (pm->pos >= pm->len)
1139 return PM_END_OF_BUFFER;
1143 static int pagemap_pte_hole(unsigned long start, unsigned long end,
1144 struct mm_walk *walk)
1146 struct pagemapread *pm = walk->private;
1147 unsigned long addr = start;
1150 while (addr < end) {
1151 struct vm_area_struct *vma = find_vma(walk->mm, addr);
1152 pagemap_entry_t pme = make_pme(0, 0);
1153 /* End of address space hole, which we mark as non-present. */
1154 unsigned long hole_end;
1157 hole_end = min(end, vma->vm_start);
1161 for (; addr < hole_end; addr += PAGE_SIZE) {
1162 err = add_to_pagemap(addr, &pme, pm);
1170 /* Addresses in the VMA. */
1171 if (vma->vm_flags & VM_SOFTDIRTY)
1172 pme = make_pme(0, PM_SOFT_DIRTY);
1173 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) {
1174 err = add_to_pagemap(addr, &pme, pm);
1183 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm,
1184 struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1186 u64 frame = 0, flags = 0;
1187 struct page *page = NULL;
1189 if (pte_present(pte)) {
1191 frame = pte_pfn(pte);
1192 flags |= PM_PRESENT;
1193 page = vm_normal_page(vma, addr, pte);
1194 if (pte_soft_dirty(pte))
1195 flags |= PM_SOFT_DIRTY;
1196 } else if (is_swap_pte(pte)) {
1198 if (pte_swp_soft_dirty(pte))
1199 flags |= PM_SOFT_DIRTY;
1200 entry = pte_to_swp_entry(pte);
1201 frame = swp_type(entry) |
1202 (swp_offset(entry) << MAX_SWAPFILES_SHIFT);
1204 if (is_migration_entry(entry))
1205 page = migration_entry_to_page(entry);
1208 if (page && !PageAnon(page))
1210 if (page && page_mapcount(page) == 1)
1211 flags |= PM_MMAP_EXCLUSIVE;
1212 if (vma->vm_flags & VM_SOFTDIRTY)
1213 flags |= PM_SOFT_DIRTY;
1215 return make_pme(frame, flags);
1218 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
1219 struct mm_walk *walk)
1221 struct vm_area_struct *vma = walk->vma;
1222 struct pagemapread *pm = walk->private;
1224 pte_t *pte, *orig_pte;
1227 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1228 ptl = pmd_trans_huge_lock(pmdp, vma);
1230 u64 flags = 0, frame = 0;
1233 if ((vma->vm_flags & VM_SOFTDIRTY) || pmd_soft_dirty(pmd))
1234 flags |= PM_SOFT_DIRTY;
1237 * Currently pmd for thp is always present because thp
1238 * can not be swapped-out, migrated, or HWPOISONed
1239 * (split in such cases instead.)
1240 * This if-check is just to prepare for future implementation.
1242 if (pmd_present(pmd)) {
1243 struct page *page = pmd_page(pmd);
1245 if (page_mapcount(page) == 1)
1246 flags |= PM_MMAP_EXCLUSIVE;
1248 flags |= PM_PRESENT;
1250 frame = pmd_pfn(pmd) +
1251 ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1254 for (; addr != end; addr += PAGE_SIZE) {
1255 pagemap_entry_t pme = make_pme(frame, flags);
1257 err = add_to_pagemap(addr, &pme, pm);
1260 if (pm->show_pfn && (flags & PM_PRESENT))
1267 if (pmd_trans_unstable(pmdp))
1269 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1272 * We can assume that @vma always points to a valid one and @end never
1273 * goes beyond vma->vm_end.
1275 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl);
1276 for (; addr < end; pte++, addr += PAGE_SIZE) {
1277 pagemap_entry_t pme;
1279 pme = pte_to_pagemap_entry(pm, vma, addr, *pte);
1280 err = add_to_pagemap(addr, &pme, pm);
1284 pte_unmap_unlock(orig_pte, ptl);
1291 #ifdef CONFIG_HUGETLB_PAGE
1292 /* This function walks within one hugetlb entry in the single call */
1293 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask,
1294 unsigned long addr, unsigned long end,
1295 struct mm_walk *walk)
1297 struct pagemapread *pm = walk->private;
1298 struct vm_area_struct *vma = walk->vma;
1299 u64 flags = 0, frame = 0;
1303 if (vma->vm_flags & VM_SOFTDIRTY)
1304 flags |= PM_SOFT_DIRTY;
1306 pte = huge_ptep_get(ptep);
1307 if (pte_present(pte)) {
1308 struct page *page = pte_page(pte);
1310 if (!PageAnon(page))
1313 if (page_mapcount(page) == 1)
1314 flags |= PM_MMAP_EXCLUSIVE;
1316 flags |= PM_PRESENT;
1318 frame = pte_pfn(pte) +
1319 ((addr & ~hmask) >> PAGE_SHIFT);
1322 for (; addr != end; addr += PAGE_SIZE) {
1323 pagemap_entry_t pme = make_pme(frame, flags);
1325 err = add_to_pagemap(addr, &pme, pm);
1328 if (pm->show_pfn && (flags & PM_PRESENT))
1336 #endif /* HUGETLB_PAGE */
1339 * /proc/pid/pagemap - an array mapping virtual pages to pfns
1341 * For each page in the address space, this file contains one 64-bit entry
1342 * consisting of the following:
1344 * Bits 0-54 page frame number (PFN) if present
1345 * Bits 0-4 swap type if swapped
1346 * Bits 5-54 swap offset if swapped
1347 * Bit 55 pte is soft-dirty (see Documentation/vm/soft-dirty.txt)
1348 * Bit 56 page exclusively mapped
1350 * Bit 61 page is file-page or shared-anon
1351 * Bit 62 page swapped
1352 * Bit 63 page present
1354 * If the page is not present but in swap, then the PFN contains an
1355 * encoding of the swap file number and the page's offset into the
1356 * swap. Unmapped pages return a null PFN. This allows determining
1357 * precisely which pages are mapped (or in swap) and comparing mapped
1358 * pages between processes.
1360 * Efficient users of this interface will use /proc/pid/maps to
1361 * determine which areas of memory are actually mapped and llseek to
1362 * skip over unmapped regions.
1364 static ssize_t pagemap_read(struct file *file, char __user *buf,
1365 size_t count, loff_t *ppos)
1367 struct mm_struct *mm = file->private_data;
1368 struct pagemapread pm;
1369 struct mm_walk pagemap_walk = {};
1371 unsigned long svpfn;
1372 unsigned long start_vaddr;
1373 unsigned long end_vaddr;
1374 int ret = 0, copied = 0;
1376 if (!mm || !atomic_inc_not_zero(&mm->mm_users))
1380 /* file position must be aligned */
1381 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
1388 /* do not disclose physical addresses: attack vector */
1389 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN);
1391 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
1392 pm.buffer = kmalloc(pm.len * PM_ENTRY_BYTES, GFP_TEMPORARY);
1397 pagemap_walk.pmd_entry = pagemap_pmd_range;
1398 pagemap_walk.pte_hole = pagemap_pte_hole;
1399 #ifdef CONFIG_HUGETLB_PAGE
1400 pagemap_walk.hugetlb_entry = pagemap_hugetlb_range;
1402 pagemap_walk.mm = mm;
1403 pagemap_walk.private = ±
1406 svpfn = src / PM_ENTRY_BYTES;
1407 start_vaddr = svpfn << PAGE_SHIFT;
1408 end_vaddr = mm->task_size;
1410 /* watch out for wraparound */
1411 if (svpfn > mm->task_size >> PAGE_SHIFT)
1412 start_vaddr = end_vaddr;
1415 * The odds are that this will stop walking way
1416 * before end_vaddr, because the length of the
1417 * user buffer is tracked in "pm", and the walk
1418 * will stop when we hit the end of the buffer.
1421 while (count && (start_vaddr < end_vaddr)) {
1426 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
1428 if (end < start_vaddr || end > end_vaddr)
1430 down_read(&mm->mmap_sem);
1431 ret = walk_page_range(start_vaddr, end, &pagemap_walk);
1432 up_read(&mm->mmap_sem);
1435 len = min(count, PM_ENTRY_BYTES * pm.pos);
1436 if (copy_to_user(buf, pm.buffer, len)) {
1445 if (!ret || ret == PM_END_OF_BUFFER)
1456 static int pagemap_open(struct inode *inode, struct file *file)
1458 struct mm_struct *mm;
1460 mm = proc_mem_open(inode, PTRACE_MODE_READ);
1463 file->private_data = mm;
1467 static int pagemap_release(struct inode *inode, struct file *file)
1469 struct mm_struct *mm = file->private_data;
1476 const struct file_operations proc_pagemap_operations = {
1477 .llseek = mem_lseek, /* borrow this */
1478 .read = pagemap_read,
1479 .open = pagemap_open,
1480 .release = pagemap_release,
1482 #endif /* CONFIG_PROC_PAGE_MONITOR */
1487 unsigned long pages;
1489 unsigned long active;
1490 unsigned long writeback;
1491 unsigned long mapcount_max;
1492 unsigned long dirty;
1493 unsigned long swapcache;
1494 unsigned long node[MAX_NUMNODES];
1497 struct numa_maps_private {
1498 struct proc_maps_private proc_maps;
1499 struct numa_maps md;
1502 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
1503 unsigned long nr_pages)
1505 int count = page_mapcount(page);
1507 md->pages += nr_pages;
1508 if (pte_dirty || PageDirty(page))
1509 md->dirty += nr_pages;
1511 if (PageSwapCache(page))
1512 md->swapcache += nr_pages;
1514 if (PageActive(page) || PageUnevictable(page))
1515 md->active += nr_pages;
1517 if (PageWriteback(page))
1518 md->writeback += nr_pages;
1521 md->anon += nr_pages;
1523 if (count > md->mapcount_max)
1524 md->mapcount_max = count;
1526 md->node[page_to_nid(page)] += nr_pages;
1529 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
1535 if (!pte_present(pte))
1538 page = vm_normal_page(vma, addr, pte);
1542 if (PageReserved(page))
1545 nid = page_to_nid(page);
1546 if (!node_isset(nid, node_states[N_MEMORY]))
1552 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1553 static struct page *can_gather_numa_stats_pmd(pmd_t pmd,
1554 struct vm_area_struct *vma,
1560 if (!pmd_present(pmd))
1563 page = vm_normal_page_pmd(vma, addr, pmd);
1567 if (PageReserved(page))
1570 nid = page_to_nid(page);
1571 if (!node_isset(nid, node_states[N_MEMORY]))
1578 static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
1579 unsigned long end, struct mm_walk *walk)
1581 struct numa_maps *md = walk->private;
1582 struct vm_area_struct *vma = walk->vma;
1587 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1588 ptl = pmd_trans_huge_lock(pmd, vma);
1592 page = can_gather_numa_stats_pmd(*pmd, vma, addr);
1594 gather_stats(page, md, pmd_dirty(*pmd),
1595 HPAGE_PMD_SIZE/PAGE_SIZE);
1600 if (pmd_trans_unstable(pmd))
1603 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
1605 struct page *page = can_gather_numa_stats(*pte, vma, addr);
1608 gather_stats(page, md, pte_dirty(*pte), 1);
1610 } while (pte++, addr += PAGE_SIZE, addr != end);
1611 pte_unmap_unlock(orig_pte, ptl);
1615 #ifdef CONFIG_HUGETLB_PAGE
1616 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1617 unsigned long addr, unsigned long end, struct mm_walk *walk)
1619 pte_t huge_pte = huge_ptep_get(pte);
1620 struct numa_maps *md;
1623 if (!pte_present(huge_pte))
1626 page = pte_page(huge_pte);
1631 gather_stats(page, md, pte_dirty(huge_pte), 1);
1636 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1637 unsigned long addr, unsigned long end, struct mm_walk *walk)
1644 * Display pages allocated per node and memory policy via /proc.
1646 static int show_numa_map(struct seq_file *m, void *v, int is_pid)
1648 struct numa_maps_private *numa_priv = m->private;
1649 struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
1650 struct vm_area_struct *vma = v;
1651 struct numa_maps *md = &numa_priv->md;
1652 struct file *file = vma->vm_file;
1653 struct mm_struct *mm = vma->vm_mm;
1654 struct mm_walk walk = {
1655 .hugetlb_entry = gather_hugetlb_stats,
1656 .pmd_entry = gather_pte_stats,
1660 struct mempolicy *pol;
1667 /* Ensure we start with an empty set of numa_maps statistics. */
1668 memset(md, 0, sizeof(*md));
1670 pol = __get_vma_policy(vma, vma->vm_start);
1672 mpol_to_str(buffer, sizeof(buffer), pol);
1675 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy);
1678 seq_printf(m, "%08lx %s", vma->vm_start, buffer);
1681 seq_puts(m, " file=");
1682 seq_file_path(m, file, "\n\t= ");
1683 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1684 seq_puts(m, " heap");
1685 } else if (is_stack(proc_priv, vma)) {
1686 seq_puts(m, " stack");
1689 if (is_vm_hugetlb_page(vma))
1690 seq_puts(m, " huge");
1692 /* mmap_sem is held by m_start */
1693 walk_page_vma(vma, &walk);
1699 seq_printf(m, " anon=%lu", md->anon);
1702 seq_printf(m, " dirty=%lu", md->dirty);
1704 if (md->pages != md->anon && md->pages != md->dirty)
1705 seq_printf(m, " mapped=%lu", md->pages);
1707 if (md->mapcount_max > 1)
1708 seq_printf(m, " mapmax=%lu", md->mapcount_max);
1711 seq_printf(m, " swapcache=%lu", md->swapcache);
1713 if (md->active < md->pages && !is_vm_hugetlb_page(vma))
1714 seq_printf(m, " active=%lu", md->active);
1717 seq_printf(m, " writeback=%lu", md->writeback);
1719 for_each_node_state(nid, N_MEMORY)
1721 seq_printf(m, " N%d=%lu", nid, md->node[nid]);
1723 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10);
1726 m_cache_vma(m, vma);
1730 static int show_pid_numa_map(struct seq_file *m, void *v)
1732 return show_numa_map(m, v, 1);
1735 static int show_tid_numa_map(struct seq_file *m, void *v)
1737 return show_numa_map(m, v, 0);
1740 static const struct seq_operations proc_pid_numa_maps_op = {
1744 .show = show_pid_numa_map,
1747 static const struct seq_operations proc_tid_numa_maps_op = {
1751 .show = show_tid_numa_map,
1754 static int numa_maps_open(struct inode *inode, struct file *file,
1755 const struct seq_operations *ops)
1757 return proc_maps_open(inode, file, ops,
1758 sizeof(struct numa_maps_private));
1761 static int pid_numa_maps_open(struct inode *inode, struct file *file)
1763 return numa_maps_open(inode, file, &proc_pid_numa_maps_op);
1766 static int tid_numa_maps_open(struct inode *inode, struct file *file)
1768 return numa_maps_open(inode, file, &proc_tid_numa_maps_op);
1771 const struct file_operations proc_pid_numa_maps_operations = {
1772 .open = pid_numa_maps_open,
1774 .llseek = seq_lseek,
1775 .release = proc_map_release,
1778 const struct file_operations proc_tid_numa_maps_operations = {
1779 .open = tid_numa_maps_open,
1781 .llseek = seq_lseek,
1782 .release = proc_map_release,
1784 #endif /* CONFIG_NUMA */