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/sched/mm.h>
15 #include <linux/swapops.h>
16 #include <linux/mmu_notifier.h>
17 #include <linux/page_idle.h>
18 #include <linux/shmem_fs.h>
21 #include <linux/uaccess.h>
22 #include <asm/tlbflush.h>
25 void task_mem(struct seq_file *m, struct mm_struct *mm)
27 unsigned long text, lib, swap, ptes, pmds, anon, file, shmem;
28 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
30 anon = get_mm_counter(mm, MM_ANONPAGES);
31 file = get_mm_counter(mm, MM_FILEPAGES);
32 shmem = get_mm_counter(mm, MM_SHMEMPAGES);
35 * Note: to minimize their overhead, mm maintains hiwater_vm and
36 * hiwater_rss only when about to *lower* total_vm or rss. Any
37 * collector of these hiwater stats must therefore get total_vm
38 * and rss too, which will usually be the higher. Barriers? not
39 * worth the effort, such snapshots can always be inconsistent.
41 hiwater_vm = total_vm = mm->total_vm;
42 if (hiwater_vm < mm->hiwater_vm)
43 hiwater_vm = mm->hiwater_vm;
44 hiwater_rss = total_rss = anon + file + shmem;
45 if (hiwater_rss < mm->hiwater_rss)
46 hiwater_rss = mm->hiwater_rss;
48 text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10;
49 lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text;
50 swap = get_mm_counter(mm, MM_SWAPENTS);
51 ptes = PTRS_PER_PTE * sizeof(pte_t) * atomic_long_read(&mm->nr_ptes);
52 pmds = PTRS_PER_PMD * sizeof(pmd_t) * mm_nr_pmds(mm);
62 "RssShmem:\t%8lu kB\n"
70 hiwater_vm << (PAGE_SHIFT-10),
71 total_vm << (PAGE_SHIFT-10),
72 mm->locked_vm << (PAGE_SHIFT-10),
73 mm->pinned_vm << (PAGE_SHIFT-10),
74 hiwater_rss << (PAGE_SHIFT-10),
75 total_rss << (PAGE_SHIFT-10),
76 anon << (PAGE_SHIFT-10),
77 file << (PAGE_SHIFT-10),
78 shmem << (PAGE_SHIFT-10),
79 mm->data_vm << (PAGE_SHIFT-10),
80 mm->stack_vm << (PAGE_SHIFT-10), text, lib,
83 swap << (PAGE_SHIFT-10));
84 hugetlb_report_usage(m, mm);
87 unsigned long task_vsize(struct mm_struct *mm)
89 return PAGE_SIZE * mm->total_vm;
92 unsigned long task_statm(struct mm_struct *mm,
93 unsigned long *shared, unsigned long *text,
94 unsigned long *data, unsigned long *resident)
96 *shared = get_mm_counter(mm, MM_FILEPAGES) +
97 get_mm_counter(mm, MM_SHMEMPAGES);
98 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
100 *data = mm->data_vm + mm->stack_vm;
101 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
107 * Save get_task_policy() for show_numa_map().
109 static void hold_task_mempolicy(struct proc_maps_private *priv)
111 struct task_struct *task = priv->task;
114 priv->task_mempolicy = get_task_policy(task);
115 mpol_get(priv->task_mempolicy);
118 static void release_task_mempolicy(struct proc_maps_private *priv)
120 mpol_put(priv->task_mempolicy);
123 static void hold_task_mempolicy(struct proc_maps_private *priv)
126 static void release_task_mempolicy(struct proc_maps_private *priv)
131 static void vma_stop(struct proc_maps_private *priv)
133 struct mm_struct *mm = priv->mm;
135 release_task_mempolicy(priv);
136 up_read(&mm->mmap_sem);
140 static struct vm_area_struct *
141 m_next_vma(struct proc_maps_private *priv, struct vm_area_struct *vma)
143 if (vma == priv->tail_vma)
145 return vma->vm_next ?: priv->tail_vma;
148 static void m_cache_vma(struct seq_file *m, struct vm_area_struct *vma)
150 if (m->count < m->size) /* vma is copied successfully */
151 m->version = m_next_vma(m->private, vma) ? vma->vm_end : -1UL;
154 static void *m_start(struct seq_file *m, loff_t *ppos)
156 struct proc_maps_private *priv = m->private;
157 unsigned long last_addr = m->version;
158 struct mm_struct *mm;
159 struct vm_area_struct *vma;
160 unsigned int pos = *ppos;
162 /* See m_cache_vma(). Zero at the start or after lseek. */
163 if (last_addr == -1UL)
166 priv->task = get_proc_task(priv->inode);
168 return ERR_PTR(-ESRCH);
171 if (!mm || !mmget_not_zero(mm))
174 down_read(&mm->mmap_sem);
175 hold_task_mempolicy(priv);
176 priv->tail_vma = get_gate_vma(mm);
179 vma = find_vma(mm, last_addr - 1);
180 if (vma && vma->vm_start <= last_addr)
181 vma = m_next_vma(priv, vma);
187 if (pos < mm->map_count) {
188 for (vma = mm->mmap; pos; pos--) {
189 m->version = vma->vm_start;
195 /* we do not bother to update m->version in this case */
196 if (pos == mm->map_count && priv->tail_vma)
197 return priv->tail_vma;
203 static void *m_next(struct seq_file *m, void *v, loff_t *pos)
205 struct proc_maps_private *priv = m->private;
206 struct vm_area_struct *next;
209 next = m_next_vma(priv, v);
215 static void m_stop(struct seq_file *m, void *v)
217 struct proc_maps_private *priv = m->private;
219 if (!IS_ERR_OR_NULL(v))
222 put_task_struct(priv->task);
227 static int proc_maps_open(struct inode *inode, struct file *file,
228 const struct seq_operations *ops, int psize)
230 struct proc_maps_private *priv = __seq_open_private(file, ops, psize);
236 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
237 if (IS_ERR(priv->mm)) {
238 int err = PTR_ERR(priv->mm);
240 seq_release_private(inode, file);
247 static int proc_map_release(struct inode *inode, struct file *file)
249 struct seq_file *seq = file->private_data;
250 struct proc_maps_private *priv = seq->private;
255 return seq_release_private(inode, file);
258 static int do_maps_open(struct inode *inode, struct file *file,
259 const struct seq_operations *ops)
261 return proc_maps_open(inode, file, ops,
262 sizeof(struct proc_maps_private));
266 * Indicate if the VMA is a stack for the given task; for
267 * /proc/PID/maps that is the stack of the main task.
269 static int is_stack(struct proc_maps_private *priv,
270 struct vm_area_struct *vma)
273 * We make no effort to guess what a given thread considers to be
274 * its "stack". It's not even well-defined for programs written
277 return vma->vm_start <= vma->vm_mm->start_stack &&
278 vma->vm_end >= vma->vm_mm->start_stack;
282 show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid)
284 struct mm_struct *mm = vma->vm_mm;
285 struct file *file = vma->vm_file;
286 struct proc_maps_private *priv = m->private;
287 vm_flags_t flags = vma->vm_flags;
288 unsigned long ino = 0;
289 unsigned long long pgoff = 0;
290 unsigned long start, end;
292 const char *name = NULL;
295 struct inode *inode = file_inode(vma->vm_file);
296 dev = inode->i_sb->s_dev;
298 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
301 /* We don't show the stack guard page in /proc/maps */
302 start = vma->vm_start;
303 if (stack_guard_page_start(vma, start))
306 if (stack_guard_page_end(vma, end))
309 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
310 seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu ",
313 flags & VM_READ ? 'r' : '-',
314 flags & VM_WRITE ? 'w' : '-',
315 flags & VM_EXEC ? 'x' : '-',
316 flags & VM_MAYSHARE ? 's' : 'p',
318 MAJOR(dev), MINOR(dev), ino);
321 * Print the dentry name for named mappings, and a
322 * special [heap] marker for the heap:
326 seq_file_path(m, file, "\n");
330 if (vma->vm_ops && vma->vm_ops->name) {
331 name = vma->vm_ops->name(vma);
336 name = arch_vma_name(vma);
343 if (vma->vm_start <= mm->brk &&
344 vma->vm_end >= mm->start_brk) {
349 if (is_stack(priv, vma))
361 static int show_map(struct seq_file *m, void *v, int is_pid)
363 show_map_vma(m, v, is_pid);
368 static int show_pid_map(struct seq_file *m, void *v)
370 return show_map(m, v, 1);
373 static int show_tid_map(struct seq_file *m, void *v)
375 return show_map(m, v, 0);
378 static const struct seq_operations proc_pid_maps_op = {
385 static const struct seq_operations proc_tid_maps_op = {
392 static int pid_maps_open(struct inode *inode, struct file *file)
394 return do_maps_open(inode, file, &proc_pid_maps_op);
397 static int tid_maps_open(struct inode *inode, struct file *file)
399 return do_maps_open(inode, file, &proc_tid_maps_op);
402 const struct file_operations proc_pid_maps_operations = {
403 .open = pid_maps_open,
406 .release = proc_map_release,
409 const struct file_operations proc_tid_maps_operations = {
410 .open = tid_maps_open,
413 .release = proc_map_release,
417 * Proportional Set Size(PSS): my share of RSS.
419 * PSS of a process is the count of pages it has in memory, where each
420 * page is divided by the number of processes sharing it. So if a
421 * process has 1000 pages all to itself, and 1000 shared with one other
422 * process, its PSS will be 1500.
424 * To keep (accumulated) division errors low, we adopt a 64bit
425 * fixed-point pss counter to minimize division errors. So (pss >>
426 * PSS_SHIFT) would be the real byte count.
428 * A shift of 12 before division means (assuming 4K page size):
429 * - 1M 3-user-pages add up to 8KB errors;
430 * - supports mapcount up to 2^24, or 16M;
431 * - supports PSS up to 2^52 bytes, or 4PB.
435 #ifdef CONFIG_PROC_PAGE_MONITOR
436 struct mem_size_stats {
437 unsigned long resident;
438 unsigned long shared_clean;
439 unsigned long shared_dirty;
440 unsigned long private_clean;
441 unsigned long private_dirty;
442 unsigned long referenced;
443 unsigned long anonymous;
444 unsigned long anonymous_thp;
445 unsigned long shmem_thp;
447 unsigned long shared_hugetlb;
448 unsigned long private_hugetlb;
451 bool check_shmem_swap;
454 static void smaps_account(struct mem_size_stats *mss, struct page *page,
455 bool compound, bool young, bool dirty)
457 int i, nr = compound ? 1 << compound_order(page) : 1;
458 unsigned long size = nr * PAGE_SIZE;
461 mss->anonymous += size;
463 mss->resident += size;
464 /* Accumulate the size in pages that have been accessed. */
465 if (young || page_is_young(page) || PageReferenced(page))
466 mss->referenced += size;
469 * page_count(page) == 1 guarantees the page is mapped exactly once.
470 * If any subpage of the compound page mapped with PTE it would elevate
473 if (page_count(page) == 1) {
474 if (dirty || PageDirty(page))
475 mss->private_dirty += size;
477 mss->private_clean += size;
478 mss->pss += (u64)size << PSS_SHIFT;
482 for (i = 0; i < nr; i++, page++) {
483 int mapcount = page_mapcount(page);
486 if (dirty || PageDirty(page))
487 mss->shared_dirty += PAGE_SIZE;
489 mss->shared_clean += PAGE_SIZE;
490 mss->pss += (PAGE_SIZE << PSS_SHIFT) / mapcount;
492 if (dirty || PageDirty(page))
493 mss->private_dirty += PAGE_SIZE;
495 mss->private_clean += PAGE_SIZE;
496 mss->pss += PAGE_SIZE << PSS_SHIFT;
502 static int smaps_pte_hole(unsigned long addr, unsigned long end,
503 struct mm_walk *walk)
505 struct mem_size_stats *mss = walk->private;
507 mss->swap += shmem_partial_swap_usage(
508 walk->vma->vm_file->f_mapping, addr, end);
514 static void smaps_pte_entry(pte_t *pte, unsigned long addr,
515 struct mm_walk *walk)
517 struct mem_size_stats *mss = walk->private;
518 struct vm_area_struct *vma = walk->vma;
519 struct page *page = NULL;
521 if (pte_present(*pte)) {
522 page = vm_normal_page(vma, addr, *pte);
523 } else if (is_swap_pte(*pte)) {
524 swp_entry_t swpent = pte_to_swp_entry(*pte);
526 if (!non_swap_entry(swpent)) {
529 mss->swap += PAGE_SIZE;
530 mapcount = swp_swapcount(swpent);
532 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT;
534 do_div(pss_delta, mapcount);
535 mss->swap_pss += pss_delta;
537 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT;
539 } else if (is_migration_entry(swpent))
540 page = migration_entry_to_page(swpent);
541 } else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap
542 && pte_none(*pte))) {
543 page = find_get_entry(vma->vm_file->f_mapping,
544 linear_page_index(vma, addr));
548 if (radix_tree_exceptional_entry(page))
549 mss->swap += PAGE_SIZE;
559 smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte));
562 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
563 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
564 struct mm_walk *walk)
566 struct mem_size_stats *mss = walk->private;
567 struct vm_area_struct *vma = walk->vma;
570 /* FOLL_DUMP will return -EFAULT on huge zero page */
571 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
572 if (IS_ERR_OR_NULL(page))
575 mss->anonymous_thp += HPAGE_PMD_SIZE;
576 else if (PageSwapBacked(page))
577 mss->shmem_thp += HPAGE_PMD_SIZE;
578 else if (is_zone_device_page(page))
581 VM_BUG_ON_PAGE(1, page);
582 smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd));
585 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
586 struct mm_walk *walk)
591 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
592 struct mm_walk *walk)
594 struct vm_area_struct *vma = walk->vma;
598 ptl = pmd_trans_huge_lock(pmd, vma);
600 smaps_pmd_entry(pmd, addr, walk);
605 if (pmd_trans_unstable(pmd))
608 * The mmap_sem held all the way back in m_start() is what
609 * keeps khugepaged out of here and from collapsing things
612 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
613 for (; addr != end; pte++, addr += PAGE_SIZE)
614 smaps_pte_entry(pte, addr, walk);
615 pte_unmap_unlock(pte - 1, ptl);
620 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
623 * Don't forget to update Documentation/ on changes.
625 static const char mnemonics[BITS_PER_LONG][2] = {
627 * In case if we meet a flag we don't know about.
629 [0 ... (BITS_PER_LONG-1)] = "??",
631 [ilog2(VM_READ)] = "rd",
632 [ilog2(VM_WRITE)] = "wr",
633 [ilog2(VM_EXEC)] = "ex",
634 [ilog2(VM_SHARED)] = "sh",
635 [ilog2(VM_MAYREAD)] = "mr",
636 [ilog2(VM_MAYWRITE)] = "mw",
637 [ilog2(VM_MAYEXEC)] = "me",
638 [ilog2(VM_MAYSHARE)] = "ms",
639 [ilog2(VM_GROWSDOWN)] = "gd",
640 [ilog2(VM_PFNMAP)] = "pf",
641 [ilog2(VM_DENYWRITE)] = "dw",
642 #ifdef CONFIG_X86_INTEL_MPX
643 [ilog2(VM_MPX)] = "mp",
645 [ilog2(VM_LOCKED)] = "lo",
646 [ilog2(VM_IO)] = "io",
647 [ilog2(VM_SEQ_READ)] = "sr",
648 [ilog2(VM_RAND_READ)] = "rr",
649 [ilog2(VM_DONTCOPY)] = "dc",
650 [ilog2(VM_DONTEXPAND)] = "de",
651 [ilog2(VM_ACCOUNT)] = "ac",
652 [ilog2(VM_NORESERVE)] = "nr",
653 [ilog2(VM_HUGETLB)] = "ht",
654 [ilog2(VM_ARCH_1)] = "ar",
655 [ilog2(VM_DONTDUMP)] = "dd",
656 #ifdef CONFIG_MEM_SOFT_DIRTY
657 [ilog2(VM_SOFTDIRTY)] = "sd",
659 [ilog2(VM_MIXEDMAP)] = "mm",
660 [ilog2(VM_HUGEPAGE)] = "hg",
661 [ilog2(VM_NOHUGEPAGE)] = "nh",
662 [ilog2(VM_MERGEABLE)] = "mg",
663 [ilog2(VM_UFFD_MISSING)]= "um",
664 [ilog2(VM_UFFD_WP)] = "uw",
665 #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
666 /* These come out via ProtectionKey: */
667 [ilog2(VM_PKEY_BIT0)] = "",
668 [ilog2(VM_PKEY_BIT1)] = "",
669 [ilog2(VM_PKEY_BIT2)] = "",
670 [ilog2(VM_PKEY_BIT3)] = "",
675 seq_puts(m, "VmFlags: ");
676 for (i = 0; i < BITS_PER_LONG; i++) {
677 if (!mnemonics[i][0])
679 if (vma->vm_flags & (1UL << i)) {
680 seq_printf(m, "%c%c ",
681 mnemonics[i][0], mnemonics[i][1]);
687 #ifdef CONFIG_HUGETLB_PAGE
688 static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,
689 unsigned long addr, unsigned long end,
690 struct mm_walk *walk)
692 struct mem_size_stats *mss = walk->private;
693 struct vm_area_struct *vma = walk->vma;
694 struct page *page = NULL;
696 if (pte_present(*pte)) {
697 page = vm_normal_page(vma, addr, *pte);
698 } else if (is_swap_pte(*pte)) {
699 swp_entry_t swpent = pte_to_swp_entry(*pte);
701 if (is_migration_entry(swpent))
702 page = migration_entry_to_page(swpent);
705 int mapcount = page_mapcount(page);
708 mss->shared_hugetlb += huge_page_size(hstate_vma(vma));
710 mss->private_hugetlb += huge_page_size(hstate_vma(vma));
714 #endif /* HUGETLB_PAGE */
716 void __weak arch_show_smap(struct seq_file *m, struct vm_area_struct *vma)
720 static int show_smap(struct seq_file *m, void *v, int is_pid)
722 struct vm_area_struct *vma = v;
723 struct mem_size_stats mss;
724 struct mm_walk smaps_walk = {
725 .pmd_entry = smaps_pte_range,
726 #ifdef CONFIG_HUGETLB_PAGE
727 .hugetlb_entry = smaps_hugetlb_range,
733 memset(&mss, 0, sizeof mss);
736 if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) {
738 * For shared or readonly shmem mappings we know that all
739 * swapped out pages belong to the shmem object, and we can
740 * obtain the swap value much more efficiently. For private
741 * writable mappings, we might have COW pages that are
742 * not affected by the parent swapped out pages of the shmem
743 * object, so we have to distinguish them during the page walk.
744 * Unless we know that the shmem object (or the part mapped by
745 * our VMA) has no swapped out pages at all.
747 unsigned long shmem_swapped = shmem_swap_usage(vma);
749 if (!shmem_swapped || (vma->vm_flags & VM_SHARED) ||
750 !(vma->vm_flags & VM_WRITE)) {
751 mss.swap = shmem_swapped;
753 mss.check_shmem_swap = true;
754 smaps_walk.pte_hole = smaps_pte_hole;
759 /* mmap_sem is held in m_start */
760 walk_page_vma(vma, &smaps_walk);
762 show_map_vma(m, vma, is_pid);
768 "Shared_Clean: %8lu kB\n"
769 "Shared_Dirty: %8lu kB\n"
770 "Private_Clean: %8lu kB\n"
771 "Private_Dirty: %8lu kB\n"
772 "Referenced: %8lu kB\n"
773 "Anonymous: %8lu kB\n"
774 "AnonHugePages: %8lu kB\n"
775 "ShmemPmdMapped: %8lu kB\n"
776 "Shared_Hugetlb: %8lu kB\n"
777 "Private_Hugetlb: %7lu kB\n"
780 "KernelPageSize: %8lu kB\n"
781 "MMUPageSize: %8lu kB\n"
783 (vma->vm_end - vma->vm_start) >> 10,
785 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)),
786 mss.shared_clean >> 10,
787 mss.shared_dirty >> 10,
788 mss.private_clean >> 10,
789 mss.private_dirty >> 10,
790 mss.referenced >> 10,
792 mss.anonymous_thp >> 10,
794 mss.shared_hugetlb >> 10,
795 mss.private_hugetlb >> 10,
797 (unsigned long)(mss.swap_pss >> (10 + PSS_SHIFT)),
798 vma_kernel_pagesize(vma) >> 10,
799 vma_mmu_pagesize(vma) >> 10,
800 (vma->vm_flags & VM_LOCKED) ?
801 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0);
803 arch_show_smap(m, vma);
804 show_smap_vma_flags(m, vma);
809 static int show_pid_smap(struct seq_file *m, void *v)
811 return show_smap(m, v, 1);
814 static int show_tid_smap(struct seq_file *m, void *v)
816 return show_smap(m, v, 0);
819 static const struct seq_operations proc_pid_smaps_op = {
823 .show = show_pid_smap
826 static const struct seq_operations proc_tid_smaps_op = {
830 .show = show_tid_smap
833 static int pid_smaps_open(struct inode *inode, struct file *file)
835 return do_maps_open(inode, file, &proc_pid_smaps_op);
838 static int tid_smaps_open(struct inode *inode, struct file *file)
840 return do_maps_open(inode, file, &proc_tid_smaps_op);
843 const struct file_operations proc_pid_smaps_operations = {
844 .open = pid_smaps_open,
847 .release = proc_map_release,
850 const struct file_operations proc_tid_smaps_operations = {
851 .open = tid_smaps_open,
854 .release = proc_map_release,
857 enum clear_refs_types {
861 CLEAR_REFS_SOFT_DIRTY,
862 CLEAR_REFS_MM_HIWATER_RSS,
866 struct clear_refs_private {
867 enum clear_refs_types type;
870 #ifdef CONFIG_MEM_SOFT_DIRTY
871 static inline void clear_soft_dirty(struct vm_area_struct *vma,
872 unsigned long addr, pte_t *pte)
875 * The soft-dirty tracker uses #PF-s to catch writes
876 * to pages, so write-protect the pte as well. See the
877 * Documentation/vm/soft-dirty.txt for full description
878 * of how soft-dirty works.
882 if (pte_present(ptent)) {
883 ptent = ptep_modify_prot_start(vma->vm_mm, addr, pte);
884 ptent = pte_wrprotect(ptent);
885 ptent = pte_clear_soft_dirty(ptent);
886 ptep_modify_prot_commit(vma->vm_mm, addr, pte, ptent);
887 } else if (is_swap_pte(ptent)) {
888 ptent = pte_swp_clear_soft_dirty(ptent);
889 set_pte_at(vma->vm_mm, addr, pte, ptent);
893 static inline void clear_soft_dirty(struct vm_area_struct *vma,
894 unsigned long addr, pte_t *pte)
899 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
900 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
901 unsigned long addr, pmd_t *pmdp)
905 /* See comment in change_huge_pmd() */
906 pmdp_invalidate(vma, addr, pmdp);
907 if (pmd_dirty(*pmdp))
908 pmd = pmd_mkdirty(pmd);
909 if (pmd_young(*pmdp))
910 pmd = pmd_mkyoung(pmd);
912 pmd = pmd_wrprotect(pmd);
913 pmd = pmd_clear_soft_dirty(pmd);
915 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
918 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
919 unsigned long addr, pmd_t *pmdp)
924 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
925 unsigned long end, struct mm_walk *walk)
927 struct clear_refs_private *cp = walk->private;
928 struct vm_area_struct *vma = walk->vma;
933 ptl = pmd_trans_huge_lock(pmd, vma);
935 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
936 clear_soft_dirty_pmd(vma, addr, pmd);
940 page = pmd_page(*pmd);
942 /* Clear accessed and referenced bits. */
943 pmdp_test_and_clear_young(vma, addr, pmd);
944 test_and_clear_page_young(page);
945 ClearPageReferenced(page);
951 if (pmd_trans_unstable(pmd))
954 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
955 for (; addr != end; pte++, addr += PAGE_SIZE) {
958 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
959 clear_soft_dirty(vma, addr, pte);
963 if (!pte_present(ptent))
966 page = vm_normal_page(vma, addr, ptent);
970 /* Clear accessed and referenced bits. */
971 ptep_test_and_clear_young(vma, addr, pte);
972 test_and_clear_page_young(page);
973 ClearPageReferenced(page);
975 pte_unmap_unlock(pte - 1, ptl);
980 static int clear_refs_test_walk(unsigned long start, unsigned long end,
981 struct mm_walk *walk)
983 struct clear_refs_private *cp = walk->private;
984 struct vm_area_struct *vma = walk->vma;
986 if (vma->vm_flags & VM_PFNMAP)
990 * Writing 1 to /proc/pid/clear_refs affects all pages.
991 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages.
992 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages.
993 * Writing 4 to /proc/pid/clear_refs affects all pages.
995 if (cp->type == CLEAR_REFS_ANON && vma->vm_file)
997 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file)
1002 static ssize_t clear_refs_write(struct file *file, const char __user *buf,
1003 size_t count, loff_t *ppos)
1005 struct task_struct *task;
1006 char buffer[PROC_NUMBUF];
1007 struct mm_struct *mm;
1008 struct vm_area_struct *vma;
1009 enum clear_refs_types type;
1013 memset(buffer, 0, sizeof(buffer));
1014 if (count > sizeof(buffer) - 1)
1015 count = sizeof(buffer) - 1;
1016 if (copy_from_user(buffer, buf, count))
1018 rv = kstrtoint(strstrip(buffer), 10, &itype);
1021 type = (enum clear_refs_types)itype;
1022 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
1025 task = get_proc_task(file_inode(file));
1028 mm = get_task_mm(task);
1030 struct clear_refs_private cp = {
1033 struct mm_walk clear_refs_walk = {
1034 .pmd_entry = clear_refs_pte_range,
1035 .test_walk = clear_refs_test_walk,
1040 if (type == CLEAR_REFS_MM_HIWATER_RSS) {
1041 if (down_write_killable(&mm->mmap_sem)) {
1047 * Writing 5 to /proc/pid/clear_refs resets the peak
1048 * resident set size to this mm's current rss value.
1050 reset_mm_hiwater_rss(mm);
1051 up_write(&mm->mmap_sem);
1055 down_read(&mm->mmap_sem);
1056 if (type == CLEAR_REFS_SOFT_DIRTY) {
1057 for (vma = mm->mmap; vma; vma = vma->vm_next) {
1058 if (!(vma->vm_flags & VM_SOFTDIRTY))
1060 up_read(&mm->mmap_sem);
1061 if (down_write_killable(&mm->mmap_sem)) {
1065 for (vma = mm->mmap; vma; vma = vma->vm_next) {
1066 vma->vm_flags &= ~VM_SOFTDIRTY;
1067 vma_set_page_prot(vma);
1069 downgrade_write(&mm->mmap_sem);
1072 mmu_notifier_invalidate_range_start(mm, 0, -1);
1074 walk_page_range(0, mm->highest_vm_end, &clear_refs_walk);
1075 if (type == CLEAR_REFS_SOFT_DIRTY)
1076 mmu_notifier_invalidate_range_end(mm, 0, -1);
1078 up_read(&mm->mmap_sem);
1082 put_task_struct(task);
1087 const struct file_operations proc_clear_refs_operations = {
1088 .write = clear_refs_write,
1089 .llseek = noop_llseek,
1096 struct pagemapread {
1097 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */
1098 pagemap_entry_t *buffer;
1102 #define PAGEMAP_WALK_SIZE (PMD_SIZE)
1103 #define PAGEMAP_WALK_MASK (PMD_MASK)
1105 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t)
1106 #define PM_PFRAME_BITS 55
1107 #define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0)
1108 #define PM_SOFT_DIRTY BIT_ULL(55)
1109 #define PM_MMAP_EXCLUSIVE BIT_ULL(56)
1110 #define PM_FILE BIT_ULL(61)
1111 #define PM_SWAP BIT_ULL(62)
1112 #define PM_PRESENT BIT_ULL(63)
1114 #define PM_END_OF_BUFFER 1
1116 static inline pagemap_entry_t make_pme(u64 frame, u64 flags)
1118 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags };
1121 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme,
1122 struct pagemapread *pm)
1124 pm->buffer[pm->pos++] = *pme;
1125 if (pm->pos >= pm->len)
1126 return PM_END_OF_BUFFER;
1130 static int pagemap_pte_hole(unsigned long start, unsigned long end,
1131 struct mm_walk *walk)
1133 struct pagemapread *pm = walk->private;
1134 unsigned long addr = start;
1137 while (addr < end) {
1138 struct vm_area_struct *vma = find_vma(walk->mm, addr);
1139 pagemap_entry_t pme = make_pme(0, 0);
1140 /* End of address space hole, which we mark as non-present. */
1141 unsigned long hole_end;
1144 hole_end = min(end, vma->vm_start);
1148 for (; addr < hole_end; addr += PAGE_SIZE) {
1149 err = add_to_pagemap(addr, &pme, pm);
1157 /* Addresses in the VMA. */
1158 if (vma->vm_flags & VM_SOFTDIRTY)
1159 pme = make_pme(0, PM_SOFT_DIRTY);
1160 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) {
1161 err = add_to_pagemap(addr, &pme, pm);
1170 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm,
1171 struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1173 u64 frame = 0, flags = 0;
1174 struct page *page = NULL;
1176 if (pte_present(pte)) {
1178 frame = pte_pfn(pte);
1179 flags |= PM_PRESENT;
1180 page = vm_normal_page(vma, addr, pte);
1181 if (pte_soft_dirty(pte))
1182 flags |= PM_SOFT_DIRTY;
1183 } else if (is_swap_pte(pte)) {
1185 if (pte_swp_soft_dirty(pte))
1186 flags |= PM_SOFT_DIRTY;
1187 entry = pte_to_swp_entry(pte);
1188 frame = swp_type(entry) |
1189 (swp_offset(entry) << MAX_SWAPFILES_SHIFT);
1191 if (is_migration_entry(entry))
1192 page = migration_entry_to_page(entry);
1195 if (page && !PageAnon(page))
1197 if (page && page_mapcount(page) == 1)
1198 flags |= PM_MMAP_EXCLUSIVE;
1199 if (vma->vm_flags & VM_SOFTDIRTY)
1200 flags |= PM_SOFT_DIRTY;
1202 return make_pme(frame, flags);
1205 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
1206 struct mm_walk *walk)
1208 struct vm_area_struct *vma = walk->vma;
1209 struct pagemapread *pm = walk->private;
1211 pte_t *pte, *orig_pte;
1214 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1215 ptl = pmd_trans_huge_lock(pmdp, vma);
1217 u64 flags = 0, frame = 0;
1220 if ((vma->vm_flags & VM_SOFTDIRTY) || pmd_soft_dirty(pmd))
1221 flags |= PM_SOFT_DIRTY;
1224 * Currently pmd for thp is always present because thp
1225 * can not be swapped-out, migrated, or HWPOISONed
1226 * (split in such cases instead.)
1227 * This if-check is just to prepare for future implementation.
1229 if (pmd_present(pmd)) {
1230 struct page *page = pmd_page(pmd);
1232 if (page_mapcount(page) == 1)
1233 flags |= PM_MMAP_EXCLUSIVE;
1235 flags |= PM_PRESENT;
1237 frame = pmd_pfn(pmd) +
1238 ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1241 for (; addr != end; addr += PAGE_SIZE) {
1242 pagemap_entry_t pme = make_pme(frame, flags);
1244 err = add_to_pagemap(addr, &pme, pm);
1247 if (pm->show_pfn && (flags & PM_PRESENT))
1254 if (pmd_trans_unstable(pmdp))
1256 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1259 * We can assume that @vma always points to a valid one and @end never
1260 * goes beyond vma->vm_end.
1262 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl);
1263 for (; addr < end; pte++, addr += PAGE_SIZE) {
1264 pagemap_entry_t pme;
1266 pme = pte_to_pagemap_entry(pm, vma, addr, *pte);
1267 err = add_to_pagemap(addr, &pme, pm);
1271 pte_unmap_unlock(orig_pte, ptl);
1278 #ifdef CONFIG_HUGETLB_PAGE
1279 /* This function walks within one hugetlb entry in the single call */
1280 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask,
1281 unsigned long addr, unsigned long end,
1282 struct mm_walk *walk)
1284 struct pagemapread *pm = walk->private;
1285 struct vm_area_struct *vma = walk->vma;
1286 u64 flags = 0, frame = 0;
1290 if (vma->vm_flags & VM_SOFTDIRTY)
1291 flags |= PM_SOFT_DIRTY;
1293 pte = huge_ptep_get(ptep);
1294 if (pte_present(pte)) {
1295 struct page *page = pte_page(pte);
1297 if (!PageAnon(page))
1300 if (page_mapcount(page) == 1)
1301 flags |= PM_MMAP_EXCLUSIVE;
1303 flags |= PM_PRESENT;
1305 frame = pte_pfn(pte) +
1306 ((addr & ~hmask) >> PAGE_SHIFT);
1309 for (; addr != end; addr += PAGE_SIZE) {
1310 pagemap_entry_t pme = make_pme(frame, flags);
1312 err = add_to_pagemap(addr, &pme, pm);
1315 if (pm->show_pfn && (flags & PM_PRESENT))
1323 #endif /* HUGETLB_PAGE */
1326 * /proc/pid/pagemap - an array mapping virtual pages to pfns
1328 * For each page in the address space, this file contains one 64-bit entry
1329 * consisting of the following:
1331 * Bits 0-54 page frame number (PFN) if present
1332 * Bits 0-4 swap type if swapped
1333 * Bits 5-54 swap offset if swapped
1334 * Bit 55 pte is soft-dirty (see Documentation/vm/soft-dirty.txt)
1335 * Bit 56 page exclusively mapped
1337 * Bit 61 page is file-page or shared-anon
1338 * Bit 62 page swapped
1339 * Bit 63 page present
1341 * If the page is not present but in swap, then the PFN contains an
1342 * encoding of the swap file number and the page's offset into the
1343 * swap. Unmapped pages return a null PFN. This allows determining
1344 * precisely which pages are mapped (or in swap) and comparing mapped
1345 * pages between processes.
1347 * Efficient users of this interface will use /proc/pid/maps to
1348 * determine which areas of memory are actually mapped and llseek to
1349 * skip over unmapped regions.
1351 static ssize_t pagemap_read(struct file *file, char __user *buf,
1352 size_t count, loff_t *ppos)
1354 struct mm_struct *mm = file->private_data;
1355 struct pagemapread pm;
1356 struct mm_walk pagemap_walk = {};
1358 unsigned long svpfn;
1359 unsigned long start_vaddr;
1360 unsigned long end_vaddr;
1361 int ret = 0, copied = 0;
1363 if (!mm || !mmget_not_zero(mm))
1367 /* file position must be aligned */
1368 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
1375 /* do not disclose physical addresses: attack vector */
1376 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN);
1378 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
1379 pm.buffer = kmalloc(pm.len * PM_ENTRY_BYTES, GFP_TEMPORARY);
1384 pagemap_walk.pmd_entry = pagemap_pmd_range;
1385 pagemap_walk.pte_hole = pagemap_pte_hole;
1386 #ifdef CONFIG_HUGETLB_PAGE
1387 pagemap_walk.hugetlb_entry = pagemap_hugetlb_range;
1389 pagemap_walk.mm = mm;
1390 pagemap_walk.private = ±
1393 svpfn = src / PM_ENTRY_BYTES;
1394 start_vaddr = svpfn << PAGE_SHIFT;
1395 end_vaddr = mm->task_size;
1397 /* watch out for wraparound */
1398 if (svpfn > mm->task_size >> PAGE_SHIFT)
1399 start_vaddr = end_vaddr;
1402 * The odds are that this will stop walking way
1403 * before end_vaddr, because the length of the
1404 * user buffer is tracked in "pm", and the walk
1405 * will stop when we hit the end of the buffer.
1408 while (count && (start_vaddr < end_vaddr)) {
1413 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
1415 if (end < start_vaddr || end > end_vaddr)
1417 down_read(&mm->mmap_sem);
1418 ret = walk_page_range(start_vaddr, end, &pagemap_walk);
1419 up_read(&mm->mmap_sem);
1422 len = min(count, PM_ENTRY_BYTES * pm.pos);
1423 if (copy_to_user(buf, pm.buffer, len)) {
1432 if (!ret || ret == PM_END_OF_BUFFER)
1443 static int pagemap_open(struct inode *inode, struct file *file)
1445 struct mm_struct *mm;
1447 mm = proc_mem_open(inode, PTRACE_MODE_READ);
1450 file->private_data = mm;
1454 static int pagemap_release(struct inode *inode, struct file *file)
1456 struct mm_struct *mm = file->private_data;
1463 const struct file_operations proc_pagemap_operations = {
1464 .llseek = mem_lseek, /* borrow this */
1465 .read = pagemap_read,
1466 .open = pagemap_open,
1467 .release = pagemap_release,
1469 #endif /* CONFIG_PROC_PAGE_MONITOR */
1474 unsigned long pages;
1476 unsigned long active;
1477 unsigned long writeback;
1478 unsigned long mapcount_max;
1479 unsigned long dirty;
1480 unsigned long swapcache;
1481 unsigned long node[MAX_NUMNODES];
1484 struct numa_maps_private {
1485 struct proc_maps_private proc_maps;
1486 struct numa_maps md;
1489 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
1490 unsigned long nr_pages)
1492 int count = page_mapcount(page);
1494 md->pages += nr_pages;
1495 if (pte_dirty || PageDirty(page))
1496 md->dirty += nr_pages;
1498 if (PageSwapCache(page))
1499 md->swapcache += nr_pages;
1501 if (PageActive(page) || PageUnevictable(page))
1502 md->active += nr_pages;
1504 if (PageWriteback(page))
1505 md->writeback += nr_pages;
1508 md->anon += nr_pages;
1510 if (count > md->mapcount_max)
1511 md->mapcount_max = count;
1513 md->node[page_to_nid(page)] += nr_pages;
1516 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
1522 if (!pte_present(pte))
1525 page = vm_normal_page(vma, addr, pte);
1529 if (PageReserved(page))
1532 nid = page_to_nid(page);
1533 if (!node_isset(nid, node_states[N_MEMORY]))
1539 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1540 static struct page *can_gather_numa_stats_pmd(pmd_t pmd,
1541 struct vm_area_struct *vma,
1547 if (!pmd_present(pmd))
1550 page = vm_normal_page_pmd(vma, addr, pmd);
1554 if (PageReserved(page))
1557 nid = page_to_nid(page);
1558 if (!node_isset(nid, node_states[N_MEMORY]))
1565 static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
1566 unsigned long end, struct mm_walk *walk)
1568 struct numa_maps *md = walk->private;
1569 struct vm_area_struct *vma = walk->vma;
1574 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1575 ptl = pmd_trans_huge_lock(pmd, vma);
1579 page = can_gather_numa_stats_pmd(*pmd, vma, addr);
1581 gather_stats(page, md, pmd_dirty(*pmd),
1582 HPAGE_PMD_SIZE/PAGE_SIZE);
1587 if (pmd_trans_unstable(pmd))
1590 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
1592 struct page *page = can_gather_numa_stats(*pte, vma, addr);
1595 gather_stats(page, md, pte_dirty(*pte), 1);
1597 } while (pte++, addr += PAGE_SIZE, addr != end);
1598 pte_unmap_unlock(orig_pte, ptl);
1602 #ifdef CONFIG_HUGETLB_PAGE
1603 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1604 unsigned long addr, unsigned long end, struct mm_walk *walk)
1606 pte_t huge_pte = huge_ptep_get(pte);
1607 struct numa_maps *md;
1610 if (!pte_present(huge_pte))
1613 page = pte_page(huge_pte);
1618 gather_stats(page, md, pte_dirty(huge_pte), 1);
1623 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1624 unsigned long addr, unsigned long end, struct mm_walk *walk)
1631 * Display pages allocated per node and memory policy via /proc.
1633 static int show_numa_map(struct seq_file *m, void *v, int is_pid)
1635 struct numa_maps_private *numa_priv = m->private;
1636 struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
1637 struct vm_area_struct *vma = v;
1638 struct numa_maps *md = &numa_priv->md;
1639 struct file *file = vma->vm_file;
1640 struct mm_struct *mm = vma->vm_mm;
1641 struct mm_walk walk = {
1642 .hugetlb_entry = gather_hugetlb_stats,
1643 .pmd_entry = gather_pte_stats,
1647 struct mempolicy *pol;
1654 /* Ensure we start with an empty set of numa_maps statistics. */
1655 memset(md, 0, sizeof(*md));
1657 pol = __get_vma_policy(vma, vma->vm_start);
1659 mpol_to_str(buffer, sizeof(buffer), pol);
1662 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy);
1665 seq_printf(m, "%08lx %s", vma->vm_start, buffer);
1668 seq_puts(m, " file=");
1669 seq_file_path(m, file, "\n\t= ");
1670 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1671 seq_puts(m, " heap");
1672 } else if (is_stack(proc_priv, vma)) {
1673 seq_puts(m, " stack");
1676 if (is_vm_hugetlb_page(vma))
1677 seq_puts(m, " huge");
1679 /* mmap_sem is held by m_start */
1680 walk_page_vma(vma, &walk);
1686 seq_printf(m, " anon=%lu", md->anon);
1689 seq_printf(m, " dirty=%lu", md->dirty);
1691 if (md->pages != md->anon && md->pages != md->dirty)
1692 seq_printf(m, " mapped=%lu", md->pages);
1694 if (md->mapcount_max > 1)
1695 seq_printf(m, " mapmax=%lu", md->mapcount_max);
1698 seq_printf(m, " swapcache=%lu", md->swapcache);
1700 if (md->active < md->pages && !is_vm_hugetlb_page(vma))
1701 seq_printf(m, " active=%lu", md->active);
1704 seq_printf(m, " writeback=%lu", md->writeback);
1706 for_each_node_state(nid, N_MEMORY)
1708 seq_printf(m, " N%d=%lu", nid, md->node[nid]);
1710 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10);
1713 m_cache_vma(m, vma);
1717 static int show_pid_numa_map(struct seq_file *m, void *v)
1719 return show_numa_map(m, v, 1);
1722 static int show_tid_numa_map(struct seq_file *m, void *v)
1724 return show_numa_map(m, v, 0);
1727 static const struct seq_operations proc_pid_numa_maps_op = {
1731 .show = show_pid_numa_map,
1734 static const struct seq_operations proc_tid_numa_maps_op = {
1738 .show = show_tid_numa_map,
1741 static int numa_maps_open(struct inode *inode, struct file *file,
1742 const struct seq_operations *ops)
1744 return proc_maps_open(inode, file, ops,
1745 sizeof(struct numa_maps_private));
1748 static int pid_numa_maps_open(struct inode *inode, struct file *file)
1750 return numa_maps_open(inode, file, &proc_pid_numa_maps_op);
1753 static int tid_numa_maps_open(struct inode *inode, struct file *file)
1755 return numa_maps_open(inode, file, &proc_tid_numa_maps_op);
1758 const struct file_operations proc_pid_numa_maps_operations = {
1759 .open = pid_numa_maps_open,
1761 .llseek = seq_lseek,
1762 .release = proc_map_release,
1765 const struct file_operations proc_tid_numa_maps_operations = {
1766 .open = tid_numa_maps_open,
1768 .llseek = seq_lseek,
1769 .release = proc_map_release,
1771 #endif /* CONFIG_NUMA */