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));
73 hugetlb_report_usage(m, mm);
76 unsigned long task_vsize(struct mm_struct *mm)
78 return PAGE_SIZE * mm->total_vm;
81 unsigned long task_statm(struct mm_struct *mm,
82 unsigned long *shared, unsigned long *text,
83 unsigned long *data, unsigned long *resident)
85 *shared = get_mm_counter(mm, MM_FILEPAGES);
86 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
88 *data = mm->total_vm - mm->shared_vm;
89 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
95 * Save get_task_policy() for show_numa_map().
97 static void hold_task_mempolicy(struct proc_maps_private *priv)
99 struct task_struct *task = priv->task;
102 priv->task_mempolicy = get_task_policy(task);
103 mpol_get(priv->task_mempolicy);
106 static void release_task_mempolicy(struct proc_maps_private *priv)
108 mpol_put(priv->task_mempolicy);
111 static void hold_task_mempolicy(struct proc_maps_private *priv)
114 static void release_task_mempolicy(struct proc_maps_private *priv)
119 static void vma_stop(struct proc_maps_private *priv)
121 struct mm_struct *mm = priv->mm;
123 release_task_mempolicy(priv);
124 up_read(&mm->mmap_sem);
128 static struct vm_area_struct *
129 m_next_vma(struct proc_maps_private *priv, struct vm_area_struct *vma)
131 if (vma == priv->tail_vma)
133 return vma->vm_next ?: priv->tail_vma;
136 static void m_cache_vma(struct seq_file *m, struct vm_area_struct *vma)
138 if (m->count < m->size) /* vma is copied successfully */
139 m->version = m_next_vma(m->private, vma) ? vma->vm_start : -1UL;
142 static void *m_start(struct seq_file *m, loff_t *ppos)
144 struct proc_maps_private *priv = m->private;
145 unsigned long last_addr = m->version;
146 struct mm_struct *mm;
147 struct vm_area_struct *vma;
148 unsigned int pos = *ppos;
150 /* See m_cache_vma(). Zero at the start or after lseek. */
151 if (last_addr == -1UL)
154 priv->task = get_proc_task(priv->inode);
156 return ERR_PTR(-ESRCH);
159 if (!mm || !atomic_inc_not_zero(&mm->mm_users))
162 down_read(&mm->mmap_sem);
163 hold_task_mempolicy(priv);
164 priv->tail_vma = get_gate_vma(mm);
167 vma = find_vma(mm, last_addr);
168 if (vma && (vma = m_next_vma(priv, vma)))
173 if (pos < mm->map_count) {
174 for (vma = mm->mmap; pos; pos--) {
175 m->version = vma->vm_start;
181 /* we do not bother to update m->version in this case */
182 if (pos == mm->map_count && priv->tail_vma)
183 return priv->tail_vma;
189 static void *m_next(struct seq_file *m, void *v, loff_t *pos)
191 struct proc_maps_private *priv = m->private;
192 struct vm_area_struct *next;
195 next = m_next_vma(priv, v);
201 static void m_stop(struct seq_file *m, void *v)
203 struct proc_maps_private *priv = m->private;
205 if (!IS_ERR_OR_NULL(v))
208 put_task_struct(priv->task);
213 static int proc_maps_open(struct inode *inode, struct file *file,
214 const struct seq_operations *ops, int psize)
216 struct proc_maps_private *priv = __seq_open_private(file, ops, psize);
222 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
223 if (IS_ERR(priv->mm)) {
224 int err = PTR_ERR(priv->mm);
226 seq_release_private(inode, file);
233 static int proc_map_release(struct inode *inode, struct file *file)
235 struct seq_file *seq = file->private_data;
236 struct proc_maps_private *priv = seq->private;
241 return seq_release_private(inode, file);
244 static int do_maps_open(struct inode *inode, struct file *file,
245 const struct seq_operations *ops)
247 return proc_maps_open(inode, file, ops,
248 sizeof(struct proc_maps_private));
251 static pid_t pid_of_stack(struct proc_maps_private *priv,
252 struct vm_area_struct *vma, bool is_pid)
254 struct inode *inode = priv->inode;
255 struct task_struct *task;
259 task = pid_task(proc_pid(inode), PIDTYPE_PID);
261 task = task_of_stack(task, vma, is_pid);
263 ret = task_pid_nr_ns(task, inode->i_sb->s_fs_info);
271 show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid)
273 struct mm_struct *mm = vma->vm_mm;
274 struct file *file = vma->vm_file;
275 struct proc_maps_private *priv = m->private;
276 vm_flags_t flags = vma->vm_flags;
277 unsigned long ino = 0;
278 unsigned long long pgoff = 0;
279 unsigned long start, end;
281 const char *name = NULL;
284 struct inode *inode = file_inode(vma->vm_file);
285 dev = inode->i_sb->s_dev;
287 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
290 /* We don't show the stack guard page in /proc/maps */
291 start = vma->vm_start;
292 if (stack_guard_page_start(vma, start))
295 if (stack_guard_page_end(vma, end))
298 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
299 seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu ",
302 flags & VM_READ ? 'r' : '-',
303 flags & VM_WRITE ? 'w' : '-',
304 flags & VM_EXEC ? 'x' : '-',
305 flags & VM_MAYSHARE ? 's' : 'p',
307 MAJOR(dev), MINOR(dev), ino);
310 * Print the dentry name for named mappings, and a
311 * special [heap] marker for the heap:
315 seq_file_path(m, file, "\n");
319 if (vma->vm_ops && vma->vm_ops->name) {
320 name = vma->vm_ops->name(vma);
325 name = arch_vma_name(vma);
334 if (vma->vm_start <= mm->brk &&
335 vma->vm_end >= mm->start_brk) {
340 tid = pid_of_stack(priv, vma, is_pid);
343 * Thread stack in /proc/PID/task/TID/maps or
344 * the main process stack.
346 if (!is_pid || (vma->vm_start <= mm->start_stack &&
347 vma->vm_end >= mm->start_stack)) {
350 /* Thread stack in /proc/PID/maps */
352 seq_printf(m, "[stack:%d]", tid);
365 static int show_map(struct seq_file *m, void *v, int is_pid)
367 show_map_vma(m, v, is_pid);
372 static int show_pid_map(struct seq_file *m, void *v)
374 return show_map(m, v, 1);
377 static int show_tid_map(struct seq_file *m, void *v)
379 return show_map(m, v, 0);
382 static const struct seq_operations proc_pid_maps_op = {
389 static const struct seq_operations proc_tid_maps_op = {
396 static int pid_maps_open(struct inode *inode, struct file *file)
398 return do_maps_open(inode, file, &proc_pid_maps_op);
401 static int tid_maps_open(struct inode *inode, struct file *file)
403 return do_maps_open(inode, file, &proc_tid_maps_op);
406 const struct file_operations proc_pid_maps_operations = {
407 .open = pid_maps_open,
410 .release = proc_map_release,
413 const struct file_operations proc_tid_maps_operations = {
414 .open = tid_maps_open,
417 .release = proc_map_release,
421 * Proportional Set Size(PSS): my share of RSS.
423 * PSS of a process is the count of pages it has in memory, where each
424 * page is divided by the number of processes sharing it. So if a
425 * process has 1000 pages all to itself, and 1000 shared with one other
426 * process, its PSS will be 1500.
428 * To keep (accumulated) division errors low, we adopt a 64bit
429 * fixed-point pss counter to minimize division errors. So (pss >>
430 * PSS_SHIFT) would be the real byte count.
432 * A shift of 12 before division means (assuming 4K page size):
433 * - 1M 3-user-pages add up to 8KB errors;
434 * - supports mapcount up to 2^24, or 16M;
435 * - supports PSS up to 2^52 bytes, or 4PB.
439 #ifdef CONFIG_PROC_PAGE_MONITOR
440 struct mem_size_stats {
441 unsigned long resident;
442 unsigned long shared_clean;
443 unsigned long shared_dirty;
444 unsigned long private_clean;
445 unsigned long private_dirty;
446 unsigned long referenced;
447 unsigned long anonymous;
448 unsigned long anonymous_thp;
450 unsigned long shared_hugetlb;
451 unsigned long private_hugetlb;
456 static void smaps_account(struct mem_size_stats *mss, struct page *page,
457 bool compound, bool young, bool dirty)
459 int i, nr = compound ? HPAGE_PMD_NR : 1;
460 unsigned long size = nr * PAGE_SIZE;
463 mss->anonymous += size;
465 mss->resident += size;
466 /* Accumulate the size in pages that have been accessed. */
467 if (young || page_is_young(page) || PageReferenced(page))
468 mss->referenced += size;
471 * page_count(page) == 1 guarantees the page is mapped exactly once.
472 * If any subpage of the compound page mapped with PTE it would elevate
475 if (page_count(page) == 1) {
476 if (dirty || PageDirty(page))
477 mss->private_dirty += size;
479 mss->private_clean += size;
480 mss->pss += (u64)size << PSS_SHIFT;
484 for (i = 0; i < nr; i++, page++) {
485 int mapcount = page_mapcount(page);
488 if (dirty || PageDirty(page))
489 mss->shared_dirty += PAGE_SIZE;
491 mss->shared_clean += PAGE_SIZE;
492 mss->pss += (PAGE_SIZE << PSS_SHIFT) / mapcount;
494 if (dirty || PageDirty(page))
495 mss->private_dirty += PAGE_SIZE;
497 mss->private_clean += PAGE_SIZE;
498 mss->pss += PAGE_SIZE << PSS_SHIFT;
503 static void smaps_pte_entry(pte_t *pte, unsigned long addr,
504 struct mm_walk *walk)
506 struct mem_size_stats *mss = walk->private;
507 struct vm_area_struct *vma = walk->vma;
508 struct page *page = NULL;
510 if (pte_present(*pte)) {
511 page = vm_normal_page(vma, addr, *pte);
512 } else if (is_swap_pte(*pte)) {
513 swp_entry_t swpent = pte_to_swp_entry(*pte);
515 if (!non_swap_entry(swpent)) {
518 mss->swap += PAGE_SIZE;
519 mapcount = swp_swapcount(swpent);
521 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT;
523 do_div(pss_delta, mapcount);
524 mss->swap_pss += pss_delta;
526 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT;
528 } else if (is_migration_entry(swpent))
529 page = migration_entry_to_page(swpent);
535 smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte));
538 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
539 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
540 struct mm_walk *walk)
542 struct mem_size_stats *mss = walk->private;
543 struct vm_area_struct *vma = walk->vma;
546 /* FOLL_DUMP will return -EFAULT on huge zero page */
547 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
548 if (IS_ERR_OR_NULL(page))
550 mss->anonymous_thp += HPAGE_PMD_SIZE;
551 smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd));
554 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
555 struct mm_walk *walk)
560 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
561 struct mm_walk *walk)
563 struct vm_area_struct *vma = walk->vma;
567 if (pmd_trans_huge_lock(pmd, vma, &ptl)) {
568 smaps_pmd_entry(pmd, addr, walk);
573 if (pmd_trans_unstable(pmd))
576 * The mmap_sem held all the way back in m_start() is what
577 * keeps khugepaged out of here and from collapsing things
580 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
581 for (; addr != end; pte++, addr += PAGE_SIZE)
582 smaps_pte_entry(pte, addr, walk);
583 pte_unmap_unlock(pte - 1, ptl);
588 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
591 * Don't forget to update Documentation/ on changes.
593 static const char mnemonics[BITS_PER_LONG][2] = {
595 * In case if we meet a flag we don't know about.
597 [0 ... (BITS_PER_LONG-1)] = "??",
599 [ilog2(VM_READ)] = "rd",
600 [ilog2(VM_WRITE)] = "wr",
601 [ilog2(VM_EXEC)] = "ex",
602 [ilog2(VM_SHARED)] = "sh",
603 [ilog2(VM_MAYREAD)] = "mr",
604 [ilog2(VM_MAYWRITE)] = "mw",
605 [ilog2(VM_MAYEXEC)] = "me",
606 [ilog2(VM_MAYSHARE)] = "ms",
607 [ilog2(VM_GROWSDOWN)] = "gd",
608 [ilog2(VM_PFNMAP)] = "pf",
609 [ilog2(VM_DENYWRITE)] = "dw",
610 #ifdef CONFIG_X86_INTEL_MPX
611 [ilog2(VM_MPX)] = "mp",
613 [ilog2(VM_LOCKED)] = "lo",
614 [ilog2(VM_IO)] = "io",
615 [ilog2(VM_SEQ_READ)] = "sr",
616 [ilog2(VM_RAND_READ)] = "rr",
617 [ilog2(VM_DONTCOPY)] = "dc",
618 [ilog2(VM_DONTEXPAND)] = "de",
619 [ilog2(VM_ACCOUNT)] = "ac",
620 [ilog2(VM_NORESERVE)] = "nr",
621 [ilog2(VM_HUGETLB)] = "ht",
622 [ilog2(VM_ARCH_1)] = "ar",
623 [ilog2(VM_DONTDUMP)] = "dd",
624 #ifdef CONFIG_MEM_SOFT_DIRTY
625 [ilog2(VM_SOFTDIRTY)] = "sd",
627 [ilog2(VM_MIXEDMAP)] = "mm",
628 [ilog2(VM_HUGEPAGE)] = "hg",
629 [ilog2(VM_NOHUGEPAGE)] = "nh",
630 [ilog2(VM_MERGEABLE)] = "mg",
631 [ilog2(VM_UFFD_MISSING)]= "um",
632 [ilog2(VM_UFFD_WP)] = "uw",
636 seq_puts(m, "VmFlags: ");
637 for (i = 0; i < BITS_PER_LONG; i++) {
638 if (vma->vm_flags & (1UL << i)) {
639 seq_printf(m, "%c%c ",
640 mnemonics[i][0], mnemonics[i][1]);
646 #ifdef CONFIG_HUGETLB_PAGE
647 static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,
648 unsigned long addr, unsigned long end,
649 struct mm_walk *walk)
651 struct mem_size_stats *mss = walk->private;
652 struct vm_area_struct *vma = walk->vma;
653 struct page *page = NULL;
655 if (pte_present(*pte)) {
656 page = vm_normal_page(vma, addr, *pte);
657 } else if (is_swap_pte(*pte)) {
658 swp_entry_t swpent = pte_to_swp_entry(*pte);
660 if (is_migration_entry(swpent))
661 page = migration_entry_to_page(swpent);
664 int mapcount = page_mapcount(page);
667 mss->shared_hugetlb += huge_page_size(hstate_vma(vma));
669 mss->private_hugetlb += huge_page_size(hstate_vma(vma));
673 #endif /* HUGETLB_PAGE */
675 static int show_smap(struct seq_file *m, void *v, int is_pid)
677 struct vm_area_struct *vma = v;
678 struct mem_size_stats mss;
679 struct mm_walk smaps_walk = {
680 .pmd_entry = smaps_pte_range,
681 #ifdef CONFIG_HUGETLB_PAGE
682 .hugetlb_entry = smaps_hugetlb_range,
688 memset(&mss, 0, sizeof mss);
689 /* mmap_sem is held in m_start */
690 walk_page_vma(vma, &smaps_walk);
692 show_map_vma(m, vma, is_pid);
698 "Shared_Clean: %8lu kB\n"
699 "Shared_Dirty: %8lu kB\n"
700 "Private_Clean: %8lu kB\n"
701 "Private_Dirty: %8lu kB\n"
702 "Referenced: %8lu kB\n"
703 "Anonymous: %8lu kB\n"
704 "AnonHugePages: %8lu kB\n"
705 "Shared_Hugetlb: %8lu kB\n"
706 "Private_Hugetlb: %8lu kB\n"
709 "KernelPageSize: %8lu kB\n"
710 "MMUPageSize: %8lu kB\n"
712 (vma->vm_end - vma->vm_start) >> 10,
714 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)),
715 mss.shared_clean >> 10,
716 mss.shared_dirty >> 10,
717 mss.private_clean >> 10,
718 mss.private_dirty >> 10,
719 mss.referenced >> 10,
721 mss.anonymous_thp >> 10,
722 mss.shared_hugetlb >> 10,
723 mss.private_hugetlb >> 10,
725 (unsigned long)(mss.swap_pss >> (10 + PSS_SHIFT)),
726 vma_kernel_pagesize(vma) >> 10,
727 vma_mmu_pagesize(vma) >> 10,
728 (vma->vm_flags & VM_LOCKED) ?
729 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0);
731 show_smap_vma_flags(m, vma);
736 static int show_pid_smap(struct seq_file *m, void *v)
738 return show_smap(m, v, 1);
741 static int show_tid_smap(struct seq_file *m, void *v)
743 return show_smap(m, v, 0);
746 static const struct seq_operations proc_pid_smaps_op = {
750 .show = show_pid_smap
753 static const struct seq_operations proc_tid_smaps_op = {
757 .show = show_tid_smap
760 static int pid_smaps_open(struct inode *inode, struct file *file)
762 return do_maps_open(inode, file, &proc_pid_smaps_op);
765 static int tid_smaps_open(struct inode *inode, struct file *file)
767 return do_maps_open(inode, file, &proc_tid_smaps_op);
770 const struct file_operations proc_pid_smaps_operations = {
771 .open = pid_smaps_open,
774 .release = proc_map_release,
777 const struct file_operations proc_tid_smaps_operations = {
778 .open = tid_smaps_open,
781 .release = proc_map_release,
784 enum clear_refs_types {
788 CLEAR_REFS_SOFT_DIRTY,
789 CLEAR_REFS_MM_HIWATER_RSS,
793 struct clear_refs_private {
794 enum clear_refs_types type;
797 #ifdef CONFIG_MEM_SOFT_DIRTY
798 static inline void clear_soft_dirty(struct vm_area_struct *vma,
799 unsigned long addr, pte_t *pte)
802 * The soft-dirty tracker uses #PF-s to catch writes
803 * to pages, so write-protect the pte as well. See the
804 * Documentation/vm/soft-dirty.txt for full description
805 * of how soft-dirty works.
809 if (pte_present(ptent)) {
810 ptent = ptep_modify_prot_start(vma->vm_mm, addr, pte);
811 ptent = pte_wrprotect(ptent);
812 ptent = pte_clear_soft_dirty(ptent);
813 ptep_modify_prot_commit(vma->vm_mm, addr, pte, ptent);
814 } else if (is_swap_pte(ptent)) {
815 ptent = pte_swp_clear_soft_dirty(ptent);
816 set_pte_at(vma->vm_mm, addr, pte, ptent);
820 static inline void clear_soft_dirty(struct vm_area_struct *vma,
821 unsigned long addr, pte_t *pte)
826 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
827 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
828 unsigned long addr, pmd_t *pmdp)
830 pmd_t pmd = pmdp_huge_get_and_clear(vma->vm_mm, addr, pmdp);
832 pmd = pmd_wrprotect(pmd);
833 pmd = pmd_clear_soft_dirty(pmd);
835 if (vma->vm_flags & VM_SOFTDIRTY)
836 vma->vm_flags &= ~VM_SOFTDIRTY;
838 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
841 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
842 unsigned long addr, pmd_t *pmdp)
847 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
848 unsigned long end, struct mm_walk *walk)
850 struct clear_refs_private *cp = walk->private;
851 struct vm_area_struct *vma = walk->vma;
856 if (pmd_trans_huge_lock(pmd, vma, &ptl)) {
857 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
858 clear_soft_dirty_pmd(vma, addr, pmd);
862 page = pmd_page(*pmd);
864 /* Clear accessed and referenced bits. */
865 pmdp_test_and_clear_young(vma, addr, pmd);
866 test_and_clear_page_young(page);
867 ClearPageReferenced(page);
873 if (pmd_trans_unstable(pmd))
876 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
877 for (; addr != end; pte++, addr += PAGE_SIZE) {
880 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
881 clear_soft_dirty(vma, addr, pte);
885 if (!pte_present(ptent))
888 page = vm_normal_page(vma, addr, ptent);
892 /* Clear accessed and referenced bits. */
893 ptep_test_and_clear_young(vma, addr, pte);
894 test_and_clear_page_young(page);
895 ClearPageReferenced(page);
897 pte_unmap_unlock(pte - 1, ptl);
902 static int clear_refs_test_walk(unsigned long start, unsigned long end,
903 struct mm_walk *walk)
905 struct clear_refs_private *cp = walk->private;
906 struct vm_area_struct *vma = walk->vma;
908 if (vma->vm_flags & VM_PFNMAP)
912 * Writing 1 to /proc/pid/clear_refs affects all pages.
913 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages.
914 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages.
915 * Writing 4 to /proc/pid/clear_refs affects all pages.
917 if (cp->type == CLEAR_REFS_ANON && vma->vm_file)
919 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file)
924 static ssize_t clear_refs_write(struct file *file, const char __user *buf,
925 size_t count, loff_t *ppos)
927 struct task_struct *task;
928 char buffer[PROC_NUMBUF];
929 struct mm_struct *mm;
930 struct vm_area_struct *vma;
931 enum clear_refs_types type;
935 memset(buffer, 0, sizeof(buffer));
936 if (count > sizeof(buffer) - 1)
937 count = sizeof(buffer) - 1;
938 if (copy_from_user(buffer, buf, count))
940 rv = kstrtoint(strstrip(buffer), 10, &itype);
943 type = (enum clear_refs_types)itype;
944 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
947 task = get_proc_task(file_inode(file));
950 mm = get_task_mm(task);
952 struct clear_refs_private cp = {
955 struct mm_walk clear_refs_walk = {
956 .pmd_entry = clear_refs_pte_range,
957 .test_walk = clear_refs_test_walk,
962 if (type == CLEAR_REFS_MM_HIWATER_RSS) {
964 * Writing 5 to /proc/pid/clear_refs resets the peak
965 * resident set size to this mm's current rss value.
967 down_write(&mm->mmap_sem);
968 reset_mm_hiwater_rss(mm);
969 up_write(&mm->mmap_sem);
973 down_read(&mm->mmap_sem);
974 if (type == CLEAR_REFS_SOFT_DIRTY) {
975 for (vma = mm->mmap; vma; vma = vma->vm_next) {
976 if (!(vma->vm_flags & VM_SOFTDIRTY))
978 up_read(&mm->mmap_sem);
979 down_write(&mm->mmap_sem);
980 for (vma = mm->mmap; vma; vma = vma->vm_next) {
981 vma->vm_flags &= ~VM_SOFTDIRTY;
982 vma_set_page_prot(vma);
984 downgrade_write(&mm->mmap_sem);
987 mmu_notifier_invalidate_range_start(mm, 0, -1);
989 walk_page_range(0, ~0UL, &clear_refs_walk);
990 if (type == CLEAR_REFS_SOFT_DIRTY)
991 mmu_notifier_invalidate_range_end(mm, 0, -1);
993 up_read(&mm->mmap_sem);
997 put_task_struct(task);
1002 const struct file_operations proc_clear_refs_operations = {
1003 .write = clear_refs_write,
1004 .llseek = noop_llseek,
1011 struct pagemapread {
1012 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */
1013 pagemap_entry_t *buffer;
1017 #define PAGEMAP_WALK_SIZE (PMD_SIZE)
1018 #define PAGEMAP_WALK_MASK (PMD_MASK)
1020 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t)
1021 #define PM_PFRAME_BITS 55
1022 #define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0)
1023 #define PM_SOFT_DIRTY BIT_ULL(55)
1024 #define PM_MMAP_EXCLUSIVE BIT_ULL(56)
1025 #define PM_FILE BIT_ULL(61)
1026 #define PM_SWAP BIT_ULL(62)
1027 #define PM_PRESENT BIT_ULL(63)
1029 #define PM_END_OF_BUFFER 1
1031 static inline pagemap_entry_t make_pme(u64 frame, u64 flags)
1033 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags };
1036 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme,
1037 struct pagemapread *pm)
1039 pm->buffer[pm->pos++] = *pme;
1040 if (pm->pos >= pm->len)
1041 return PM_END_OF_BUFFER;
1045 static int pagemap_pte_hole(unsigned long start, unsigned long end,
1046 struct mm_walk *walk)
1048 struct pagemapread *pm = walk->private;
1049 unsigned long addr = start;
1052 while (addr < end) {
1053 struct vm_area_struct *vma = find_vma(walk->mm, addr);
1054 pagemap_entry_t pme = make_pme(0, 0);
1055 /* End of address space hole, which we mark as non-present. */
1056 unsigned long hole_end;
1059 hole_end = min(end, vma->vm_start);
1063 for (; addr < hole_end; addr += PAGE_SIZE) {
1064 err = add_to_pagemap(addr, &pme, pm);
1072 /* Addresses in the VMA. */
1073 if (vma->vm_flags & VM_SOFTDIRTY)
1074 pme = make_pme(0, PM_SOFT_DIRTY);
1075 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) {
1076 err = add_to_pagemap(addr, &pme, pm);
1085 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm,
1086 struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1088 u64 frame = 0, flags = 0;
1089 struct page *page = NULL;
1091 if (pte_present(pte)) {
1093 frame = pte_pfn(pte);
1094 flags |= PM_PRESENT;
1095 page = vm_normal_page(vma, addr, pte);
1096 if (pte_soft_dirty(pte))
1097 flags |= PM_SOFT_DIRTY;
1098 } else if (is_swap_pte(pte)) {
1100 if (pte_swp_soft_dirty(pte))
1101 flags |= PM_SOFT_DIRTY;
1102 entry = pte_to_swp_entry(pte);
1103 frame = swp_type(entry) |
1104 (swp_offset(entry) << MAX_SWAPFILES_SHIFT);
1106 if (is_migration_entry(entry))
1107 page = migration_entry_to_page(entry);
1110 if (page && !PageAnon(page))
1112 if (page && page_mapcount(page) == 1)
1113 flags |= PM_MMAP_EXCLUSIVE;
1114 if (vma->vm_flags & VM_SOFTDIRTY)
1115 flags |= PM_SOFT_DIRTY;
1117 return make_pme(frame, flags);
1120 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
1121 struct mm_walk *walk)
1123 struct vm_area_struct *vma = walk->vma;
1124 struct pagemapread *pm = walk->private;
1126 pte_t *pte, *orig_pte;
1129 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1130 if (pmd_trans_huge_lock(pmdp, vma, &ptl)) {
1131 u64 flags = 0, frame = 0;
1134 if ((vma->vm_flags & VM_SOFTDIRTY) || pmd_soft_dirty(pmd))
1135 flags |= PM_SOFT_DIRTY;
1138 * Currently pmd for thp is always present because thp
1139 * can not be swapped-out, migrated, or HWPOISONed
1140 * (split in such cases instead.)
1141 * This if-check is just to prepare for future implementation.
1143 if (pmd_present(pmd)) {
1144 struct page *page = pmd_page(pmd);
1146 if (page_mapcount(page) == 1)
1147 flags |= PM_MMAP_EXCLUSIVE;
1149 flags |= PM_PRESENT;
1151 frame = pmd_pfn(pmd) +
1152 ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1155 for (; addr != end; addr += PAGE_SIZE) {
1156 pagemap_entry_t pme = make_pme(frame, flags);
1158 err = add_to_pagemap(addr, &pme, pm);
1161 if (pm->show_pfn && (flags & PM_PRESENT))
1168 if (pmd_trans_unstable(pmdp))
1170 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1173 * We can assume that @vma always points to a valid one and @end never
1174 * goes beyond vma->vm_end.
1176 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl);
1177 for (; addr < end; pte++, addr += PAGE_SIZE) {
1178 pagemap_entry_t pme;
1180 pme = pte_to_pagemap_entry(pm, vma, addr, *pte);
1181 err = add_to_pagemap(addr, &pme, pm);
1185 pte_unmap_unlock(orig_pte, ptl);
1192 #ifdef CONFIG_HUGETLB_PAGE
1193 /* This function walks within one hugetlb entry in the single call */
1194 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask,
1195 unsigned long addr, unsigned long end,
1196 struct mm_walk *walk)
1198 struct pagemapread *pm = walk->private;
1199 struct vm_area_struct *vma = walk->vma;
1200 u64 flags = 0, frame = 0;
1204 if (vma->vm_flags & VM_SOFTDIRTY)
1205 flags |= PM_SOFT_DIRTY;
1207 pte = huge_ptep_get(ptep);
1208 if (pte_present(pte)) {
1209 struct page *page = pte_page(pte);
1211 if (!PageAnon(page))
1214 if (page_mapcount(page) == 1)
1215 flags |= PM_MMAP_EXCLUSIVE;
1217 flags |= PM_PRESENT;
1219 frame = pte_pfn(pte) +
1220 ((addr & ~hmask) >> PAGE_SHIFT);
1223 for (; addr != end; addr += PAGE_SIZE) {
1224 pagemap_entry_t pme = make_pme(frame, flags);
1226 err = add_to_pagemap(addr, &pme, pm);
1229 if (pm->show_pfn && (flags & PM_PRESENT))
1237 #endif /* HUGETLB_PAGE */
1240 * /proc/pid/pagemap - an array mapping virtual pages to pfns
1242 * For each page in the address space, this file contains one 64-bit entry
1243 * consisting of the following:
1245 * Bits 0-54 page frame number (PFN) if present
1246 * Bits 0-4 swap type if swapped
1247 * Bits 5-54 swap offset if swapped
1248 * Bit 55 pte is soft-dirty (see Documentation/vm/soft-dirty.txt)
1249 * Bit 56 page exclusively mapped
1251 * Bit 61 page is file-page or shared-anon
1252 * Bit 62 page swapped
1253 * Bit 63 page present
1255 * If the page is not present but in swap, then the PFN contains an
1256 * encoding of the swap file number and the page's offset into the
1257 * swap. Unmapped pages return a null PFN. This allows determining
1258 * precisely which pages are mapped (or in swap) and comparing mapped
1259 * pages between processes.
1261 * Efficient users of this interface will use /proc/pid/maps to
1262 * determine which areas of memory are actually mapped and llseek to
1263 * skip over unmapped regions.
1265 static ssize_t pagemap_read(struct file *file, char __user *buf,
1266 size_t count, loff_t *ppos)
1268 struct mm_struct *mm = file->private_data;
1269 struct pagemapread pm;
1270 struct mm_walk pagemap_walk = {};
1272 unsigned long svpfn;
1273 unsigned long start_vaddr;
1274 unsigned long end_vaddr;
1275 int ret = 0, copied = 0;
1277 if (!mm || !atomic_inc_not_zero(&mm->mm_users))
1281 /* file position must be aligned */
1282 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
1289 /* do not disclose physical addresses: attack vector */
1290 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN);
1292 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
1293 pm.buffer = kmalloc(pm.len * PM_ENTRY_BYTES, GFP_TEMPORARY);
1298 pagemap_walk.pmd_entry = pagemap_pmd_range;
1299 pagemap_walk.pte_hole = pagemap_pte_hole;
1300 #ifdef CONFIG_HUGETLB_PAGE
1301 pagemap_walk.hugetlb_entry = pagemap_hugetlb_range;
1303 pagemap_walk.mm = mm;
1304 pagemap_walk.private = ±
1307 svpfn = src / PM_ENTRY_BYTES;
1308 start_vaddr = svpfn << PAGE_SHIFT;
1309 end_vaddr = mm->task_size;
1311 /* watch out for wraparound */
1312 if (svpfn > mm->task_size >> PAGE_SHIFT)
1313 start_vaddr = end_vaddr;
1316 * The odds are that this will stop walking way
1317 * before end_vaddr, because the length of the
1318 * user buffer is tracked in "pm", and the walk
1319 * will stop when we hit the end of the buffer.
1322 while (count && (start_vaddr < end_vaddr)) {
1327 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
1329 if (end < start_vaddr || end > end_vaddr)
1331 down_read(&mm->mmap_sem);
1332 ret = walk_page_range(start_vaddr, end, &pagemap_walk);
1333 up_read(&mm->mmap_sem);
1336 len = min(count, PM_ENTRY_BYTES * pm.pos);
1337 if (copy_to_user(buf, pm.buffer, len)) {
1346 if (!ret || ret == PM_END_OF_BUFFER)
1357 static int pagemap_open(struct inode *inode, struct file *file)
1359 struct mm_struct *mm;
1361 mm = proc_mem_open(inode, PTRACE_MODE_READ);
1364 file->private_data = mm;
1368 static int pagemap_release(struct inode *inode, struct file *file)
1370 struct mm_struct *mm = file->private_data;
1377 const struct file_operations proc_pagemap_operations = {
1378 .llseek = mem_lseek, /* borrow this */
1379 .read = pagemap_read,
1380 .open = pagemap_open,
1381 .release = pagemap_release,
1383 #endif /* CONFIG_PROC_PAGE_MONITOR */
1388 unsigned long pages;
1390 unsigned long active;
1391 unsigned long writeback;
1392 unsigned long mapcount_max;
1393 unsigned long dirty;
1394 unsigned long swapcache;
1395 unsigned long node[MAX_NUMNODES];
1398 struct numa_maps_private {
1399 struct proc_maps_private proc_maps;
1400 struct numa_maps md;
1403 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
1404 unsigned long nr_pages)
1406 int count = page_mapcount(page);
1408 md->pages += nr_pages;
1409 if (pte_dirty || PageDirty(page))
1410 md->dirty += nr_pages;
1412 if (PageSwapCache(page))
1413 md->swapcache += nr_pages;
1415 if (PageActive(page) || PageUnevictable(page))
1416 md->active += nr_pages;
1418 if (PageWriteback(page))
1419 md->writeback += nr_pages;
1422 md->anon += nr_pages;
1424 if (count > md->mapcount_max)
1425 md->mapcount_max = count;
1427 md->node[page_to_nid(page)] += nr_pages;
1430 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
1436 if (!pte_present(pte))
1439 page = vm_normal_page(vma, addr, pte);
1443 if (PageReserved(page))
1446 nid = page_to_nid(page);
1447 if (!node_isset(nid, node_states[N_MEMORY]))
1453 static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
1454 unsigned long end, struct mm_walk *walk)
1456 struct numa_maps *md = walk->private;
1457 struct vm_area_struct *vma = walk->vma;
1462 if (pmd_trans_huge_lock(pmd, vma, &ptl)) {
1463 pte_t huge_pte = *(pte_t *)pmd;
1466 page = can_gather_numa_stats(huge_pte, vma, addr);
1468 gather_stats(page, md, pte_dirty(huge_pte),
1469 HPAGE_PMD_SIZE/PAGE_SIZE);
1474 if (pmd_trans_unstable(pmd))
1476 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
1478 struct page *page = can_gather_numa_stats(*pte, vma, addr);
1481 gather_stats(page, md, pte_dirty(*pte), 1);
1483 } while (pte++, addr += PAGE_SIZE, addr != end);
1484 pte_unmap_unlock(orig_pte, ptl);
1487 #ifdef CONFIG_HUGETLB_PAGE
1488 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1489 unsigned long addr, unsigned long end, struct mm_walk *walk)
1491 struct numa_maps *md;
1494 if (!pte_present(*pte))
1497 page = pte_page(*pte);
1502 gather_stats(page, md, pte_dirty(*pte), 1);
1507 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1508 unsigned long addr, unsigned long end, struct mm_walk *walk)
1515 * Display pages allocated per node and memory policy via /proc.
1517 static int show_numa_map(struct seq_file *m, void *v, int is_pid)
1519 struct numa_maps_private *numa_priv = m->private;
1520 struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
1521 struct vm_area_struct *vma = v;
1522 struct numa_maps *md = &numa_priv->md;
1523 struct file *file = vma->vm_file;
1524 struct mm_struct *mm = vma->vm_mm;
1525 struct mm_walk walk = {
1526 .hugetlb_entry = gather_hugetlb_stats,
1527 .pmd_entry = gather_pte_stats,
1531 struct mempolicy *pol;
1538 /* Ensure we start with an empty set of numa_maps statistics. */
1539 memset(md, 0, sizeof(*md));
1541 pol = __get_vma_policy(vma, vma->vm_start);
1543 mpol_to_str(buffer, sizeof(buffer), pol);
1546 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy);
1549 seq_printf(m, "%08lx %s", vma->vm_start, buffer);
1552 seq_puts(m, " file=");
1553 seq_file_path(m, file, "\n\t= ");
1554 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1555 seq_puts(m, " heap");
1557 pid_t tid = pid_of_stack(proc_priv, vma, is_pid);
1560 * Thread stack in /proc/PID/task/TID/maps or
1561 * the main process stack.
1563 if (!is_pid || (vma->vm_start <= mm->start_stack &&
1564 vma->vm_end >= mm->start_stack))
1565 seq_puts(m, " stack");
1567 seq_printf(m, " stack:%d", tid);
1571 if (is_vm_hugetlb_page(vma))
1572 seq_puts(m, " huge");
1574 /* mmap_sem is held by m_start */
1575 walk_page_vma(vma, &walk);
1581 seq_printf(m, " anon=%lu", md->anon);
1584 seq_printf(m, " dirty=%lu", md->dirty);
1586 if (md->pages != md->anon && md->pages != md->dirty)
1587 seq_printf(m, " mapped=%lu", md->pages);
1589 if (md->mapcount_max > 1)
1590 seq_printf(m, " mapmax=%lu", md->mapcount_max);
1593 seq_printf(m, " swapcache=%lu", md->swapcache);
1595 if (md->active < md->pages && !is_vm_hugetlb_page(vma))
1596 seq_printf(m, " active=%lu", md->active);
1599 seq_printf(m, " writeback=%lu", md->writeback);
1601 for_each_node_state(nid, N_MEMORY)
1603 seq_printf(m, " N%d=%lu", nid, md->node[nid]);
1605 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10);
1608 m_cache_vma(m, vma);
1612 static int show_pid_numa_map(struct seq_file *m, void *v)
1614 return show_numa_map(m, v, 1);
1617 static int show_tid_numa_map(struct seq_file *m, void *v)
1619 return show_numa_map(m, v, 0);
1622 static const struct seq_operations proc_pid_numa_maps_op = {
1626 .show = show_pid_numa_map,
1629 static const struct seq_operations proc_tid_numa_maps_op = {
1633 .show = show_tid_numa_map,
1636 static int numa_maps_open(struct inode *inode, struct file *file,
1637 const struct seq_operations *ops)
1639 return proc_maps_open(inode, file, ops,
1640 sizeof(struct numa_maps_private));
1643 static int pid_numa_maps_open(struct inode *inode, struct file *file)
1645 return numa_maps_open(inode, file, &proc_pid_numa_maps_op);
1648 static int tid_numa_maps_open(struct inode *inode, struct file *file)
1650 return numa_maps_open(inode, file, &proc_tid_numa_maps_op);
1653 const struct file_operations proc_pid_numa_maps_operations = {
1654 .open = pid_numa_maps_open,
1656 .llseek = seq_lseek,
1657 .release = proc_map_release,
1660 const struct file_operations proc_tid_numa_maps_operations = {
1661 .open = tid_numa_maps_open,
1663 .llseek = seq_lseek,
1664 .release = proc_map_release,
1666 #endif /* CONFIG_NUMA */