2 #include <linux/vmacache.h>
3 #include <linux/hugetlb.h>
4 #include <linux/huge_mm.h>
5 #include <linux/mount.h>
6 #include <linux/seq_file.h>
7 #include <linux/highmem.h>
8 #include <linux/ptrace.h>
9 #include <linux/slab.h>
10 #include <linux/pagemap.h>
11 #include <linux/mempolicy.h>
12 #include <linux/rmap.h>
13 #include <linux/swap.h>
14 #include <linux/swapops.h>
15 #include <linux/mmu_notifier.h>
18 #include <asm/uaccess.h>
19 #include <asm/tlbflush.h>
22 void task_mem(struct seq_file
*m
, struct mm_struct
*mm
)
24 unsigned long data
, text
, lib
, swap
;
25 unsigned long hiwater_vm
, total_vm
, hiwater_rss
, total_rss
;
28 * Note: to minimize their overhead, mm maintains hiwater_vm and
29 * hiwater_rss only when about to *lower* total_vm or rss. Any
30 * collector of these hiwater stats must therefore get total_vm
31 * and rss too, which will usually be the higher. Barriers? not
32 * worth the effort, such snapshots can always be inconsistent.
34 hiwater_vm
= total_vm
= mm
->total_vm
;
35 if (hiwater_vm
< mm
->hiwater_vm
)
36 hiwater_vm
= mm
->hiwater_vm
;
37 hiwater_rss
= total_rss
= get_mm_rss(mm
);
38 if (hiwater_rss
< mm
->hiwater_rss
)
39 hiwater_rss
= mm
->hiwater_rss
;
41 data
= mm
->total_vm
- mm
->shared_vm
- mm
->stack_vm
;
42 text
= (PAGE_ALIGN(mm
->end_code
) - (mm
->start_code
& PAGE_MASK
)) >> 10;
43 lib
= (mm
->exec_vm
<< (PAGE_SHIFT
-10)) - text
;
44 swap
= get_mm_counter(mm
, MM_SWAPENTS
);
58 hiwater_vm
<< (PAGE_SHIFT
-10),
59 total_vm
<< (PAGE_SHIFT
-10),
60 mm
->locked_vm
<< (PAGE_SHIFT
-10),
61 mm
->pinned_vm
<< (PAGE_SHIFT
-10),
62 hiwater_rss
<< (PAGE_SHIFT
-10),
63 total_rss
<< (PAGE_SHIFT
-10),
64 data
<< (PAGE_SHIFT
-10),
65 mm
->stack_vm
<< (PAGE_SHIFT
-10), text
, lib
,
66 (PTRS_PER_PTE
* sizeof(pte_t
) *
67 atomic_long_read(&mm
->nr_ptes
)) >> 10,
68 swap
<< (PAGE_SHIFT
-10));
71 unsigned long task_vsize(struct mm_struct
*mm
)
73 return PAGE_SIZE
* mm
->total_vm
;
76 unsigned long task_statm(struct mm_struct
*mm
,
77 unsigned long *shared
, unsigned long *text
,
78 unsigned long *data
, unsigned long *resident
)
80 *shared
= get_mm_counter(mm
, MM_FILEPAGES
);
81 *text
= (PAGE_ALIGN(mm
->end_code
) - (mm
->start_code
& PAGE_MASK
))
83 *data
= mm
->total_vm
- mm
->shared_vm
;
84 *resident
= *shared
+ get_mm_counter(mm
, MM_ANONPAGES
);
90 * Save get_task_policy() for show_numa_map().
92 static void hold_task_mempolicy(struct proc_maps_private
*priv
)
94 struct task_struct
*task
= priv
->task
;
97 priv
->task_mempolicy
= get_task_policy(task
);
98 mpol_get(priv
->task_mempolicy
);
101 static void release_task_mempolicy(struct proc_maps_private
*priv
)
103 mpol_put(priv
->task_mempolicy
);
106 static void hold_task_mempolicy(struct proc_maps_private
*priv
)
109 static void release_task_mempolicy(struct proc_maps_private
*priv
)
114 static void vma_stop(struct proc_maps_private
*priv
)
116 struct mm_struct
*mm
= priv
->mm
;
118 release_task_mempolicy(priv
);
119 up_read(&mm
->mmap_sem
);
123 static struct vm_area_struct
*
124 m_next_vma(struct proc_maps_private
*priv
, struct vm_area_struct
*vma
)
126 if (vma
== priv
->tail_vma
)
128 return vma
->vm_next
?: priv
->tail_vma
;
131 static void m_cache_vma(struct seq_file
*m
, struct vm_area_struct
*vma
)
133 if (m
->count
< m
->size
) /* vma is copied successfully */
134 m
->version
= m_next_vma(m
->private, vma
) ? vma
->vm_start
: -1UL;
137 static void *m_start(struct seq_file
*m
, loff_t
*ppos
)
139 struct proc_maps_private
*priv
= m
->private;
140 unsigned long last_addr
= m
->version
;
141 struct mm_struct
*mm
;
142 struct vm_area_struct
*vma
;
143 unsigned int pos
= *ppos
;
145 /* See m_cache_vma(). Zero at the start or after lseek. */
146 if (last_addr
== -1UL)
149 priv
->task
= get_proc_task(priv
->inode
);
151 return ERR_PTR(-ESRCH
);
154 if (!mm
|| !atomic_inc_not_zero(&mm
->mm_users
))
157 down_read(&mm
->mmap_sem
);
158 hold_task_mempolicy(priv
);
159 priv
->tail_vma
= get_gate_vma(mm
);
162 vma
= find_vma(mm
, last_addr
);
163 if (vma
&& (vma
= m_next_vma(priv
, vma
)))
168 if (pos
< mm
->map_count
) {
169 for (vma
= mm
->mmap
; pos
; pos
--) {
170 m
->version
= vma
->vm_start
;
176 /* we do not bother to update m->version in this case */
177 if (pos
== mm
->map_count
&& priv
->tail_vma
)
178 return priv
->tail_vma
;
184 static void *m_next(struct seq_file
*m
, void *v
, loff_t
*pos
)
186 struct proc_maps_private
*priv
= m
->private;
187 struct vm_area_struct
*next
;
190 next
= m_next_vma(priv
, v
);
196 static void m_stop(struct seq_file
*m
, void *v
)
198 struct proc_maps_private
*priv
= m
->private;
200 if (!IS_ERR_OR_NULL(v
))
203 put_task_struct(priv
->task
);
208 static int proc_maps_open(struct inode
*inode
, struct file
*file
,
209 const struct seq_operations
*ops
, int psize
)
211 struct proc_maps_private
*priv
= __seq_open_private(file
, ops
, psize
);
217 priv
->mm
= proc_mem_open(inode
, PTRACE_MODE_READ
);
218 if (IS_ERR(priv
->mm
)) {
219 int err
= PTR_ERR(priv
->mm
);
221 seq_release_private(inode
, file
);
228 static int proc_map_release(struct inode
*inode
, struct file
*file
)
230 struct seq_file
*seq
= file
->private_data
;
231 struct proc_maps_private
*priv
= seq
->private;
236 return seq_release_private(inode
, file
);
239 static int do_maps_open(struct inode
*inode
, struct file
*file
,
240 const struct seq_operations
*ops
)
242 return proc_maps_open(inode
, file
, ops
,
243 sizeof(struct proc_maps_private
));
246 static pid_t
pid_of_stack(struct proc_maps_private
*priv
,
247 struct vm_area_struct
*vma
, bool is_pid
)
249 struct inode
*inode
= priv
->inode
;
250 struct task_struct
*task
;
254 task
= pid_task(proc_pid(inode
), PIDTYPE_PID
);
256 task
= task_of_stack(task
, vma
, is_pid
);
258 ret
= task_pid_nr_ns(task
, inode
->i_sb
->s_fs_info
);
266 show_map_vma(struct seq_file
*m
, struct vm_area_struct
*vma
, int is_pid
)
268 struct mm_struct
*mm
= vma
->vm_mm
;
269 struct file
*file
= vma
->vm_file
;
270 struct proc_maps_private
*priv
= m
->private;
271 vm_flags_t flags
= vma
->vm_flags
;
272 unsigned long ino
= 0;
273 unsigned long long pgoff
= 0;
274 unsigned long start
, end
;
276 const char *name
= NULL
;
279 struct inode
*inode
= file_inode(vma
->vm_file
);
280 dev
= inode
->i_sb
->s_dev
;
282 pgoff
= ((loff_t
)vma
->vm_pgoff
) << PAGE_SHIFT
;
285 /* We don't show the stack guard page in /proc/maps */
286 start
= vma
->vm_start
;
287 if (stack_guard_page_start(vma
, start
))
290 if (stack_guard_page_end(vma
, end
))
293 seq_setwidth(m
, 25 + sizeof(void *) * 6 - 1);
294 seq_printf(m
, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu ",
297 flags
& VM_READ
? 'r' : '-',
298 flags
& VM_WRITE
? 'w' : '-',
299 flags
& VM_EXEC
? 'x' : '-',
300 flags
& VM_MAYSHARE
? 's' : 'p',
302 MAJOR(dev
), MINOR(dev
), ino
);
305 * Print the dentry name for named mappings, and a
306 * special [heap] marker for the heap:
310 seq_path(m
, &file
->f_path
, "\n");
314 if (vma
->vm_ops
&& vma
->vm_ops
->name
) {
315 name
= vma
->vm_ops
->name(vma
);
320 name
= arch_vma_name(vma
);
329 if (vma
->vm_start
<= mm
->brk
&&
330 vma
->vm_end
>= mm
->start_brk
) {
335 tid
= pid_of_stack(priv
, vma
, is_pid
);
338 * Thread stack in /proc/PID/task/TID/maps or
339 * the main process stack.
341 if (!is_pid
|| (vma
->vm_start
<= mm
->start_stack
&&
342 vma
->vm_end
>= mm
->start_stack
)) {
345 /* Thread stack in /proc/PID/maps */
347 seq_printf(m
, "[stack:%d]", tid
);
360 static int show_map(struct seq_file
*m
, void *v
, int is_pid
)
362 show_map_vma(m
, v
, is_pid
);
367 static int show_pid_map(struct seq_file
*m
, void *v
)
369 return show_map(m
, v
, 1);
372 static int show_tid_map(struct seq_file
*m
, void *v
)
374 return show_map(m
, v
, 0);
377 static const struct seq_operations proc_pid_maps_op
= {
384 static const struct seq_operations proc_tid_maps_op
= {
391 static int pid_maps_open(struct inode
*inode
, struct file
*file
)
393 return do_maps_open(inode
, file
, &proc_pid_maps_op
);
396 static int tid_maps_open(struct inode
*inode
, struct file
*file
)
398 return do_maps_open(inode
, file
, &proc_tid_maps_op
);
401 const struct file_operations proc_pid_maps_operations
= {
402 .open
= pid_maps_open
,
405 .release
= proc_map_release
,
408 const struct file_operations proc_tid_maps_operations
= {
409 .open
= tid_maps_open
,
412 .release
= proc_map_release
,
416 * Proportional Set Size(PSS): my share of RSS.
418 * PSS of a process is the count of pages it has in memory, where each
419 * page is divided by the number of processes sharing it. So if a
420 * process has 1000 pages all to itself, and 1000 shared with one other
421 * process, its PSS will be 1500.
423 * To keep (accumulated) division errors low, we adopt a 64bit
424 * fixed-point pss counter to minimize division errors. So (pss >>
425 * PSS_SHIFT) would be the real byte count.
427 * A shift of 12 before division means (assuming 4K page size):
428 * - 1M 3-user-pages add up to 8KB errors;
429 * - supports mapcount up to 2^24, or 16M;
430 * - supports PSS up to 2^52 bytes, or 4PB.
434 #ifdef CONFIG_PROC_PAGE_MONITOR
435 struct mem_size_stats
{
436 struct vm_area_struct
*vma
;
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
;
446 unsigned long nonlinear
;
451 static void smaps_pte_entry(pte_t ptent
, unsigned long addr
,
452 unsigned long ptent_size
, struct mm_walk
*walk
)
454 struct mem_size_stats
*mss
= walk
->private;
455 struct vm_area_struct
*vma
= mss
->vma
;
456 pgoff_t pgoff
= linear_page_index(vma
, addr
);
457 struct page
*page
= NULL
;
460 if (pte_present(ptent
)) {
461 page
= vm_normal_page(vma
, addr
, ptent
);
462 } else if (is_swap_pte(ptent
)) {
463 swp_entry_t swpent
= pte_to_swp_entry(ptent
);
465 if (!non_swap_entry(swpent
))
466 mss
->swap
+= ptent_size
;
467 else if (is_migration_entry(swpent
))
468 page
= migration_entry_to_page(swpent
);
469 } else if (pte_file(ptent
)) {
470 if (pte_to_pgoff(ptent
) != pgoff
)
471 mss
->nonlinear
+= ptent_size
;
478 mss
->anonymous
+= ptent_size
;
480 if (page
->index
!= pgoff
)
481 mss
->nonlinear
+= ptent_size
;
483 mss
->resident
+= ptent_size
;
484 /* Accumulate the size in pages that have been accessed. */
485 if (pte_young(ptent
) || PageReferenced(page
))
486 mss
->referenced
+= ptent_size
;
487 mapcount
= page_mapcount(page
);
489 if (pte_dirty(ptent
) || PageDirty(page
))
490 mss
->shared_dirty
+= ptent_size
;
492 mss
->shared_clean
+= ptent_size
;
493 mss
->pss
+= (ptent_size
<< PSS_SHIFT
) / mapcount
;
495 if (pte_dirty(ptent
) || PageDirty(page
))
496 mss
->private_dirty
+= ptent_size
;
498 mss
->private_clean
+= ptent_size
;
499 mss
->pss
+= (ptent_size
<< PSS_SHIFT
);
503 static int smaps_pte_range(pmd_t
*pmd
, unsigned long addr
, unsigned long end
,
504 struct mm_walk
*walk
)
506 struct mem_size_stats
*mss
= walk
->private;
507 struct vm_area_struct
*vma
= mss
->vma
;
511 if (pmd_trans_huge_lock(pmd
, vma
, &ptl
) == 1) {
512 smaps_pte_entry(*(pte_t
*)pmd
, addr
, HPAGE_PMD_SIZE
, walk
);
514 mss
->anonymous_thp
+= HPAGE_PMD_SIZE
;
518 if (pmd_trans_unstable(pmd
))
521 * The mmap_sem held all the way back in m_start() is what
522 * keeps khugepaged out of here and from collapsing things
525 pte
= pte_offset_map_lock(vma
->vm_mm
, pmd
, addr
, &ptl
);
526 for (; addr
!= end
; pte
++, addr
+= PAGE_SIZE
)
527 smaps_pte_entry(*pte
, addr
, PAGE_SIZE
, walk
);
528 pte_unmap_unlock(pte
- 1, ptl
);
533 static void show_smap_vma_flags(struct seq_file
*m
, struct vm_area_struct
*vma
)
536 * Don't forget to update Documentation/ on changes.
538 static const char mnemonics
[BITS_PER_LONG
][2] = {
540 * In case if we meet a flag we don't know about.
542 [0 ... (BITS_PER_LONG
-1)] = "??",
544 [ilog2(VM_READ
)] = "rd",
545 [ilog2(VM_WRITE
)] = "wr",
546 [ilog2(VM_EXEC
)] = "ex",
547 [ilog2(VM_SHARED
)] = "sh",
548 [ilog2(VM_MAYREAD
)] = "mr",
549 [ilog2(VM_MAYWRITE
)] = "mw",
550 [ilog2(VM_MAYEXEC
)] = "me",
551 [ilog2(VM_MAYSHARE
)] = "ms",
552 [ilog2(VM_GROWSDOWN
)] = "gd",
553 [ilog2(VM_PFNMAP
)] = "pf",
554 [ilog2(VM_DENYWRITE
)] = "dw",
555 [ilog2(VM_LOCKED
)] = "lo",
556 [ilog2(VM_IO
)] = "io",
557 [ilog2(VM_SEQ_READ
)] = "sr",
558 [ilog2(VM_RAND_READ
)] = "rr",
559 [ilog2(VM_DONTCOPY
)] = "dc",
560 [ilog2(VM_DONTEXPAND
)] = "de",
561 [ilog2(VM_ACCOUNT
)] = "ac",
562 [ilog2(VM_NORESERVE
)] = "nr",
563 [ilog2(VM_HUGETLB
)] = "ht",
564 [ilog2(VM_NONLINEAR
)] = "nl",
565 [ilog2(VM_ARCH_1
)] = "ar",
566 [ilog2(VM_DONTDUMP
)] = "dd",
567 #ifdef CONFIG_MEM_SOFT_DIRTY
568 [ilog2(VM_SOFTDIRTY
)] = "sd",
570 [ilog2(VM_MIXEDMAP
)] = "mm",
571 [ilog2(VM_HUGEPAGE
)] = "hg",
572 [ilog2(VM_NOHUGEPAGE
)] = "nh",
573 [ilog2(VM_MERGEABLE
)] = "mg",
577 seq_puts(m
, "VmFlags: ");
578 for (i
= 0; i
< BITS_PER_LONG
; i
++) {
579 if (vma
->vm_flags
& (1UL << i
)) {
580 seq_printf(m
, "%c%c ",
581 mnemonics
[i
][0], mnemonics
[i
][1]);
587 static int show_smap(struct seq_file
*m
, void *v
, int is_pid
)
589 struct vm_area_struct
*vma
= v
;
590 struct mem_size_stats mss
;
591 struct mm_walk smaps_walk
= {
592 .pmd_entry
= smaps_pte_range
,
597 memset(&mss
, 0, sizeof mss
);
599 /* mmap_sem is held in m_start */
600 if (vma
->vm_mm
&& !is_vm_hugetlb_page(vma
))
601 walk_page_range(vma
->vm_start
, vma
->vm_end
, &smaps_walk
);
603 show_map_vma(m
, vma
, is_pid
);
609 "Shared_Clean: %8lu kB\n"
610 "Shared_Dirty: %8lu kB\n"
611 "Private_Clean: %8lu kB\n"
612 "Private_Dirty: %8lu kB\n"
613 "Referenced: %8lu kB\n"
614 "Anonymous: %8lu kB\n"
615 "AnonHugePages: %8lu kB\n"
617 "KernelPageSize: %8lu kB\n"
618 "MMUPageSize: %8lu kB\n"
620 (vma
->vm_end
- vma
->vm_start
) >> 10,
622 (unsigned long)(mss
.pss
>> (10 + PSS_SHIFT
)),
623 mss
.shared_clean
>> 10,
624 mss
.shared_dirty
>> 10,
625 mss
.private_clean
>> 10,
626 mss
.private_dirty
>> 10,
627 mss
.referenced
>> 10,
629 mss
.anonymous_thp
>> 10,
631 vma_kernel_pagesize(vma
) >> 10,
632 vma_mmu_pagesize(vma
) >> 10,
633 (vma
->vm_flags
& VM_LOCKED
) ?
634 (unsigned long)(mss
.pss
>> (10 + PSS_SHIFT
)) : 0);
636 if (vma
->vm_flags
& VM_NONLINEAR
)
637 seq_printf(m
, "Nonlinear: %8lu kB\n",
638 mss
.nonlinear
>> 10);
640 show_smap_vma_flags(m
, vma
);
645 static int show_pid_smap(struct seq_file
*m
, void *v
)
647 return show_smap(m
, v
, 1);
650 static int show_tid_smap(struct seq_file
*m
, void *v
)
652 return show_smap(m
, v
, 0);
655 static const struct seq_operations proc_pid_smaps_op
= {
659 .show
= show_pid_smap
662 static const struct seq_operations proc_tid_smaps_op
= {
666 .show
= show_tid_smap
669 static int pid_smaps_open(struct inode
*inode
, struct file
*file
)
671 return do_maps_open(inode
, file
, &proc_pid_smaps_op
);
674 static int tid_smaps_open(struct inode
*inode
, struct file
*file
)
676 return do_maps_open(inode
, file
, &proc_tid_smaps_op
);
679 const struct file_operations proc_pid_smaps_operations
= {
680 .open
= pid_smaps_open
,
683 .release
= proc_map_release
,
686 const struct file_operations proc_tid_smaps_operations
= {
687 .open
= tid_smaps_open
,
690 .release
= proc_map_release
,
694 * We do not want to have constant page-shift bits sitting in
695 * pagemap entries and are about to reuse them some time soon.
697 * Here's the "migration strategy":
698 * 1. when the system boots these bits remain what they are,
699 * but a warning about future change is printed in log;
700 * 2. once anyone clears soft-dirty bits via clear_refs file,
701 * these flag is set to denote, that user is aware of the
702 * new API and those page-shift bits change their meaning.
703 * The respective warning is printed in dmesg;
704 * 3. In a couple of releases we will remove all the mentions
705 * of page-shift in pagemap entries.
708 static bool soft_dirty_cleared __read_mostly
;
710 enum clear_refs_types
{
714 CLEAR_REFS_SOFT_DIRTY
,
718 struct clear_refs_private
{
719 struct vm_area_struct
*vma
;
720 enum clear_refs_types type
;
723 static inline void clear_soft_dirty(struct vm_area_struct
*vma
,
724 unsigned long addr
, pte_t
*pte
)
726 #ifdef CONFIG_MEM_SOFT_DIRTY
728 * The soft-dirty tracker uses #PF-s to catch writes
729 * to pages, so write-protect the pte as well. See the
730 * Documentation/vm/soft-dirty.txt for full description
731 * of how soft-dirty works.
735 if (pte_present(ptent
)) {
736 ptent
= pte_wrprotect(ptent
);
737 ptent
= pte_clear_flags(ptent
, _PAGE_SOFT_DIRTY
);
738 } else if (is_swap_pte(ptent
)) {
739 ptent
= pte_swp_clear_soft_dirty(ptent
);
740 } else if (pte_file(ptent
)) {
741 ptent
= pte_file_clear_soft_dirty(ptent
);
744 set_pte_at(vma
->vm_mm
, addr
, pte
, ptent
);
748 static int clear_refs_pte_range(pmd_t
*pmd
, unsigned long addr
,
749 unsigned long end
, struct mm_walk
*walk
)
751 struct clear_refs_private
*cp
= walk
->private;
752 struct vm_area_struct
*vma
= cp
->vma
;
757 split_huge_page_pmd(vma
, addr
, pmd
);
758 if (pmd_trans_unstable(pmd
))
761 pte
= pte_offset_map_lock(vma
->vm_mm
, pmd
, addr
, &ptl
);
762 for (; addr
!= end
; pte
++, addr
+= PAGE_SIZE
) {
765 if (cp
->type
== CLEAR_REFS_SOFT_DIRTY
) {
766 clear_soft_dirty(vma
, addr
, pte
);
770 if (!pte_present(ptent
))
773 page
= vm_normal_page(vma
, addr
, ptent
);
777 /* Clear accessed and referenced bits. */
778 ptep_test_and_clear_young(vma
, addr
, pte
);
779 ClearPageReferenced(page
);
781 pte_unmap_unlock(pte
- 1, ptl
);
786 static ssize_t
clear_refs_write(struct file
*file
, const char __user
*buf
,
787 size_t count
, loff_t
*ppos
)
789 struct task_struct
*task
;
790 char buffer
[PROC_NUMBUF
];
791 struct mm_struct
*mm
;
792 struct vm_area_struct
*vma
;
793 enum clear_refs_types type
;
797 memset(buffer
, 0, sizeof(buffer
));
798 if (count
> sizeof(buffer
) - 1)
799 count
= sizeof(buffer
) - 1;
800 if (copy_from_user(buffer
, buf
, count
))
802 rv
= kstrtoint(strstrip(buffer
), 10, &itype
);
805 type
= (enum clear_refs_types
)itype
;
806 if (type
< CLEAR_REFS_ALL
|| type
>= CLEAR_REFS_LAST
)
809 if (type
== CLEAR_REFS_SOFT_DIRTY
) {
810 soft_dirty_cleared
= true;
811 pr_warn_once("The pagemap bits 55-60 has changed their meaning!"
812 " See the linux/Documentation/vm/pagemap.txt for "
816 task
= get_proc_task(file_inode(file
));
819 mm
= get_task_mm(task
);
821 struct clear_refs_private cp
= {
824 struct mm_walk clear_refs_walk
= {
825 .pmd_entry
= clear_refs_pte_range
,
829 down_read(&mm
->mmap_sem
);
830 if (type
== CLEAR_REFS_SOFT_DIRTY
) {
831 for (vma
= mm
->mmap
; vma
; vma
= vma
->vm_next
) {
832 if (!(vma
->vm_flags
& VM_SOFTDIRTY
))
834 up_read(&mm
->mmap_sem
);
835 down_write(&mm
->mmap_sem
);
836 for (vma
= mm
->mmap
; vma
; vma
= vma
->vm_next
) {
837 vma
->vm_flags
&= ~VM_SOFTDIRTY
;
838 vma_set_page_prot(vma
);
840 downgrade_write(&mm
->mmap_sem
);
843 mmu_notifier_invalidate_range_start(mm
, 0, -1);
845 for (vma
= mm
->mmap
; vma
; vma
= vma
->vm_next
) {
847 if (is_vm_hugetlb_page(vma
))
850 * Writing 1 to /proc/pid/clear_refs affects all pages.
852 * Writing 2 to /proc/pid/clear_refs only affects
855 * Writing 3 to /proc/pid/clear_refs only affects file
858 * Writing 4 to /proc/pid/clear_refs affects all pages.
860 if (type
== CLEAR_REFS_ANON
&& vma
->vm_file
)
862 if (type
== CLEAR_REFS_MAPPED
&& !vma
->vm_file
)
864 walk_page_range(vma
->vm_start
, vma
->vm_end
,
867 if (type
== CLEAR_REFS_SOFT_DIRTY
)
868 mmu_notifier_invalidate_range_end(mm
, 0, -1);
870 up_read(&mm
->mmap_sem
);
873 put_task_struct(task
);
878 const struct file_operations proc_clear_refs_operations
= {
879 .write
= clear_refs_write
,
880 .llseek
= noop_llseek
,
888 int pos
, len
; /* units: PM_ENTRY_BYTES, not bytes */
889 pagemap_entry_t
*buffer
;
893 #define PAGEMAP_WALK_SIZE (PMD_SIZE)
894 #define PAGEMAP_WALK_MASK (PMD_MASK)
896 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t)
897 #define PM_STATUS_BITS 3
898 #define PM_STATUS_OFFSET (64 - PM_STATUS_BITS)
899 #define PM_STATUS_MASK (((1LL << PM_STATUS_BITS) - 1) << PM_STATUS_OFFSET)
900 #define PM_STATUS(nr) (((nr) << PM_STATUS_OFFSET) & PM_STATUS_MASK)
901 #define PM_PSHIFT_BITS 6
902 #define PM_PSHIFT_OFFSET (PM_STATUS_OFFSET - PM_PSHIFT_BITS)
903 #define PM_PSHIFT_MASK (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET)
904 #define __PM_PSHIFT(x) (((u64) (x) << PM_PSHIFT_OFFSET) & PM_PSHIFT_MASK)
905 #define PM_PFRAME_MASK ((1LL << PM_PSHIFT_OFFSET) - 1)
906 #define PM_PFRAME(x) ((x) & PM_PFRAME_MASK)
907 /* in "new" pagemap pshift bits are occupied with more status bits */
908 #define PM_STATUS2(v2, x) (__PM_PSHIFT(v2 ? x : PAGE_SHIFT))
910 #define __PM_SOFT_DIRTY (1LL)
911 #define PM_PRESENT PM_STATUS(4LL)
912 #define PM_SWAP PM_STATUS(2LL)
913 #define PM_FILE PM_STATUS(1LL)
914 #define PM_NOT_PRESENT(v2) PM_STATUS2(v2, 0)
915 #define PM_END_OF_BUFFER 1
917 static inline pagemap_entry_t
make_pme(u64 val
)
919 return (pagemap_entry_t
) { .pme
= val
};
922 static int add_to_pagemap(unsigned long addr
, pagemap_entry_t
*pme
,
923 struct pagemapread
*pm
)
925 pm
->buffer
[pm
->pos
++] = *pme
;
926 if (pm
->pos
>= pm
->len
)
927 return PM_END_OF_BUFFER
;
931 static int pagemap_pte_hole(unsigned long start
, unsigned long end
,
932 struct mm_walk
*walk
)
934 struct pagemapread
*pm
= walk
->private;
935 unsigned long addr
= start
;
939 struct vm_area_struct
*vma
= find_vma(walk
->mm
, addr
);
940 pagemap_entry_t pme
= make_pme(PM_NOT_PRESENT(pm
->v2
));
941 /* End of address space hole, which we mark as non-present. */
942 unsigned long hole_end
;
945 hole_end
= min(end
, vma
->vm_start
);
949 for (; addr
< hole_end
; addr
+= PAGE_SIZE
) {
950 err
= add_to_pagemap(addr
, &pme
, pm
);
958 /* Addresses in the VMA. */
959 if (vma
->vm_flags
& VM_SOFTDIRTY
)
960 pme
.pme
|= PM_STATUS2(pm
->v2
, __PM_SOFT_DIRTY
);
961 for (; addr
< min(end
, vma
->vm_end
); addr
+= PAGE_SIZE
) {
962 err
= add_to_pagemap(addr
, &pme
, pm
);
971 static void pte_to_pagemap_entry(pagemap_entry_t
*pme
, struct pagemapread
*pm
,
972 struct vm_area_struct
*vma
, unsigned long addr
, pte_t pte
)
975 struct page
*page
= NULL
;
978 if (pte_present(pte
)) {
979 frame
= pte_pfn(pte
);
981 page
= vm_normal_page(vma
, addr
, pte
);
982 if (pte_soft_dirty(pte
))
983 flags2
|= __PM_SOFT_DIRTY
;
984 } else if (is_swap_pte(pte
)) {
986 if (pte_swp_soft_dirty(pte
))
987 flags2
|= __PM_SOFT_DIRTY
;
988 entry
= pte_to_swp_entry(pte
);
989 frame
= swp_type(entry
) |
990 (swp_offset(entry
) << MAX_SWAPFILES_SHIFT
);
992 if (is_migration_entry(entry
))
993 page
= migration_entry_to_page(entry
);
995 if (vma
->vm_flags
& VM_SOFTDIRTY
)
996 flags2
|= __PM_SOFT_DIRTY
;
997 *pme
= make_pme(PM_NOT_PRESENT(pm
->v2
) | PM_STATUS2(pm
->v2
, flags2
));
1001 if (page
&& !PageAnon(page
))
1003 if ((vma
->vm_flags
& VM_SOFTDIRTY
))
1004 flags2
|= __PM_SOFT_DIRTY
;
1006 *pme
= make_pme(PM_PFRAME(frame
) | PM_STATUS2(pm
->v2
, flags2
) | flags
);
1009 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1010 static void thp_pmd_to_pagemap_entry(pagemap_entry_t
*pme
, struct pagemapread
*pm
,
1011 pmd_t pmd
, int offset
, int pmd_flags2
)
1014 * Currently pmd for thp is always present because thp can not be
1015 * swapped-out, migrated, or HWPOISONed (split in such cases instead.)
1016 * This if-check is just to prepare for future implementation.
1018 if (pmd_present(pmd
))
1019 *pme
= make_pme(PM_PFRAME(pmd_pfn(pmd
) + offset
)
1020 | PM_STATUS2(pm
->v2
, pmd_flags2
) | PM_PRESENT
);
1022 *pme
= make_pme(PM_NOT_PRESENT(pm
->v2
) | PM_STATUS2(pm
->v2
, pmd_flags2
));
1025 static inline void thp_pmd_to_pagemap_entry(pagemap_entry_t
*pme
, struct pagemapread
*pm
,
1026 pmd_t pmd
, int offset
, int pmd_flags2
)
1031 static int pagemap_pte_range(pmd_t
*pmd
, unsigned long addr
, unsigned long end
,
1032 struct mm_walk
*walk
)
1034 struct vm_area_struct
*vma
;
1035 struct pagemapread
*pm
= walk
->private;
1040 /* find the first VMA at or above 'addr' */
1041 vma
= find_vma(walk
->mm
, addr
);
1042 if (vma
&& pmd_trans_huge_lock(pmd
, vma
, &ptl
) == 1) {
1045 if ((vma
->vm_flags
& VM_SOFTDIRTY
) || pmd_soft_dirty(*pmd
))
1046 pmd_flags2
= __PM_SOFT_DIRTY
;
1050 for (; addr
!= end
; addr
+= PAGE_SIZE
) {
1051 unsigned long offset
;
1052 pagemap_entry_t pme
;
1054 offset
= (addr
& ~PAGEMAP_WALK_MASK
) >>
1056 thp_pmd_to_pagemap_entry(&pme
, pm
, *pmd
, offset
, pmd_flags2
);
1057 err
= add_to_pagemap(addr
, &pme
, pm
);
1065 if (pmd_trans_unstable(pmd
))
1069 /* End of address space hole, which we mark as non-present. */
1070 unsigned long hole_end
;
1073 hole_end
= min(end
, vma
->vm_start
);
1077 for (; addr
< hole_end
; addr
+= PAGE_SIZE
) {
1078 pagemap_entry_t pme
= make_pme(PM_NOT_PRESENT(pm
->v2
));
1080 err
= add_to_pagemap(addr
, &pme
, pm
);
1085 if (!vma
|| vma
->vm_start
>= end
)
1088 * We can't possibly be in a hugetlb VMA. In general,
1089 * for a mm_walk with a pmd_entry and a hugetlb_entry,
1090 * the pmd_entry can only be called on addresses in a
1091 * hugetlb if the walk starts in a non-hugetlb VMA and
1092 * spans a hugepage VMA. Since pagemap_read walks are
1093 * PMD-sized and PMD-aligned, this will never be true.
1095 BUG_ON(is_vm_hugetlb_page(vma
));
1097 /* Addresses in the VMA. */
1098 for (; addr
< min(end
, vma
->vm_end
); addr
+= PAGE_SIZE
) {
1099 pagemap_entry_t pme
;
1100 pte
= pte_offset_map(pmd
, addr
);
1101 pte_to_pagemap_entry(&pme
, pm
, vma
, addr
, *pte
);
1103 err
= add_to_pagemap(addr
, &pme
, pm
);
1111 vma
= find_vma(walk
->mm
, addr
);
1119 #ifdef CONFIG_HUGETLB_PAGE
1120 static void huge_pte_to_pagemap_entry(pagemap_entry_t
*pme
, struct pagemapread
*pm
,
1121 pte_t pte
, int offset
, int flags2
)
1123 if (pte_present(pte
))
1124 *pme
= make_pme(PM_PFRAME(pte_pfn(pte
) + offset
) |
1125 PM_STATUS2(pm
->v2
, flags2
) |
1128 *pme
= make_pme(PM_NOT_PRESENT(pm
->v2
) |
1129 PM_STATUS2(pm
->v2
, flags2
));
1132 /* This function walks within one hugetlb entry in the single call */
1133 static int pagemap_hugetlb_range(pte_t
*pte
, unsigned long hmask
,
1134 unsigned long addr
, unsigned long end
,
1135 struct mm_walk
*walk
)
1137 struct pagemapread
*pm
= walk
->private;
1138 struct vm_area_struct
*vma
;
1141 pagemap_entry_t pme
;
1143 vma
= find_vma(walk
->mm
, addr
);
1146 if (vma
&& (vma
->vm_flags
& VM_SOFTDIRTY
))
1147 flags2
= __PM_SOFT_DIRTY
;
1151 for (; addr
!= end
; addr
+= PAGE_SIZE
) {
1152 int offset
= (addr
& ~hmask
) >> PAGE_SHIFT
;
1153 huge_pte_to_pagemap_entry(&pme
, pm
, *pte
, offset
, flags2
);
1154 err
= add_to_pagemap(addr
, &pme
, pm
);
1163 #endif /* HUGETLB_PAGE */
1166 * /proc/pid/pagemap - an array mapping virtual pages to pfns
1168 * For each page in the address space, this file contains one 64-bit entry
1169 * consisting of the following:
1171 * Bits 0-54 page frame number (PFN) if present
1172 * Bits 0-4 swap type if swapped
1173 * Bits 5-54 swap offset if swapped
1174 * Bits 55-60 page shift (page size = 1<<page shift)
1175 * Bit 61 page is file-page or shared-anon
1176 * Bit 62 page swapped
1177 * Bit 63 page present
1179 * If the page is not present but in swap, then the PFN contains an
1180 * encoding of the swap file number and the page's offset into the
1181 * swap. Unmapped pages return a null PFN. This allows determining
1182 * precisely which pages are mapped (or in swap) and comparing mapped
1183 * pages between processes.
1185 * Efficient users of this interface will use /proc/pid/maps to
1186 * determine which areas of memory are actually mapped and llseek to
1187 * skip over unmapped regions.
1189 static ssize_t
pagemap_read(struct file
*file
, char __user
*buf
,
1190 size_t count
, loff_t
*ppos
)
1192 struct task_struct
*task
= get_proc_task(file_inode(file
));
1193 struct mm_struct
*mm
;
1194 struct pagemapread pm
;
1196 struct mm_walk pagemap_walk
= {};
1198 unsigned long svpfn
;
1199 unsigned long start_vaddr
;
1200 unsigned long end_vaddr
;
1207 /* file position must be aligned */
1208 if ((*ppos
% PM_ENTRY_BYTES
) || (count
% PM_ENTRY_BYTES
))
1215 pm
.v2
= soft_dirty_cleared
;
1216 pm
.len
= (PAGEMAP_WALK_SIZE
>> PAGE_SHIFT
);
1217 pm
.buffer
= kmalloc(pm
.len
* PM_ENTRY_BYTES
, GFP_TEMPORARY
);
1222 mm
= mm_access(task
, PTRACE_MODE_READ
);
1224 if (!mm
|| IS_ERR(mm
))
1227 pagemap_walk
.pmd_entry
= pagemap_pte_range
;
1228 pagemap_walk
.pte_hole
= pagemap_pte_hole
;
1229 #ifdef CONFIG_HUGETLB_PAGE
1230 pagemap_walk
.hugetlb_entry
= pagemap_hugetlb_range
;
1232 pagemap_walk
.mm
= mm
;
1233 pagemap_walk
.private = &pm
;
1236 svpfn
= src
/ PM_ENTRY_BYTES
;
1237 start_vaddr
= svpfn
<< PAGE_SHIFT
;
1238 end_vaddr
= TASK_SIZE_OF(task
);
1240 /* watch out for wraparound */
1241 if (svpfn
> TASK_SIZE_OF(task
) >> PAGE_SHIFT
)
1242 start_vaddr
= end_vaddr
;
1245 * The odds are that this will stop walking way
1246 * before end_vaddr, because the length of the
1247 * user buffer is tracked in "pm", and the walk
1248 * will stop when we hit the end of the buffer.
1251 while (count
&& (start_vaddr
< end_vaddr
)) {
1256 end
= (start_vaddr
+ PAGEMAP_WALK_SIZE
) & PAGEMAP_WALK_MASK
;
1258 if (end
< start_vaddr
|| end
> end_vaddr
)
1260 down_read(&mm
->mmap_sem
);
1261 ret
= walk_page_range(start_vaddr
, end
, &pagemap_walk
);
1262 up_read(&mm
->mmap_sem
);
1265 len
= min(count
, PM_ENTRY_BYTES
* pm
.pos
);
1266 if (copy_to_user(buf
, pm
.buffer
, len
)) {
1275 if (!ret
|| ret
== PM_END_OF_BUFFER
)
1283 put_task_struct(task
);
1288 static int pagemap_open(struct inode
*inode
, struct file
*file
)
1290 pr_warn_once("Bits 55-60 of /proc/PID/pagemap entries are about "
1291 "to stop being page-shift some time soon. See the "
1292 "linux/Documentation/vm/pagemap.txt for details.\n");
1296 const struct file_operations proc_pagemap_operations
= {
1297 .llseek
= mem_lseek
, /* borrow this */
1298 .read
= pagemap_read
,
1299 .open
= pagemap_open
,
1301 #endif /* CONFIG_PROC_PAGE_MONITOR */
1306 struct vm_area_struct
*vma
;
1307 unsigned long pages
;
1309 unsigned long active
;
1310 unsigned long writeback
;
1311 unsigned long mapcount_max
;
1312 unsigned long dirty
;
1313 unsigned long swapcache
;
1314 unsigned long node
[MAX_NUMNODES
];
1317 struct numa_maps_private
{
1318 struct proc_maps_private proc_maps
;
1319 struct numa_maps md
;
1322 static void gather_stats(struct page
*page
, struct numa_maps
*md
, int pte_dirty
,
1323 unsigned long nr_pages
)
1325 int count
= page_mapcount(page
);
1327 md
->pages
+= nr_pages
;
1328 if (pte_dirty
|| PageDirty(page
))
1329 md
->dirty
+= nr_pages
;
1331 if (PageSwapCache(page
))
1332 md
->swapcache
+= nr_pages
;
1334 if (PageActive(page
) || PageUnevictable(page
))
1335 md
->active
+= nr_pages
;
1337 if (PageWriteback(page
))
1338 md
->writeback
+= nr_pages
;
1341 md
->anon
+= nr_pages
;
1343 if (count
> md
->mapcount_max
)
1344 md
->mapcount_max
= count
;
1346 md
->node
[page_to_nid(page
)] += nr_pages
;
1349 static struct page
*can_gather_numa_stats(pte_t pte
, struct vm_area_struct
*vma
,
1355 if (!pte_present(pte
))
1358 page
= vm_normal_page(vma
, addr
, pte
);
1362 if (PageReserved(page
))
1365 nid
= page_to_nid(page
);
1366 if (!node_isset(nid
, node_states
[N_MEMORY
]))
1372 static int gather_pte_stats(pmd_t
*pmd
, unsigned long addr
,
1373 unsigned long end
, struct mm_walk
*walk
)
1375 struct numa_maps
*md
;
1382 if (pmd_trans_huge_lock(pmd
, md
->vma
, &ptl
) == 1) {
1383 pte_t huge_pte
= *(pte_t
*)pmd
;
1386 page
= can_gather_numa_stats(huge_pte
, md
->vma
, addr
);
1388 gather_stats(page
, md
, pte_dirty(huge_pte
),
1389 HPAGE_PMD_SIZE
/PAGE_SIZE
);
1394 if (pmd_trans_unstable(pmd
))
1396 orig_pte
= pte
= pte_offset_map_lock(walk
->mm
, pmd
, addr
, &ptl
);
1398 struct page
*page
= can_gather_numa_stats(*pte
, md
->vma
, addr
);
1401 gather_stats(page
, md
, pte_dirty(*pte
), 1);
1403 } while (pte
++, addr
+= PAGE_SIZE
, addr
!= end
);
1404 pte_unmap_unlock(orig_pte
, ptl
);
1407 #ifdef CONFIG_HUGETLB_PAGE
1408 static int gather_hugetbl_stats(pte_t
*pte
, unsigned long hmask
,
1409 unsigned long addr
, unsigned long end
, struct mm_walk
*walk
)
1411 struct numa_maps
*md
;
1414 if (!pte_present(*pte
))
1417 page
= pte_page(*pte
);
1422 gather_stats(page
, md
, pte_dirty(*pte
), 1);
1427 static int gather_hugetbl_stats(pte_t
*pte
, unsigned long hmask
,
1428 unsigned long addr
, unsigned long end
, struct mm_walk
*walk
)
1435 * Display pages allocated per node and memory policy via /proc.
1437 static int show_numa_map(struct seq_file
*m
, void *v
, int is_pid
)
1439 struct numa_maps_private
*numa_priv
= m
->private;
1440 struct proc_maps_private
*proc_priv
= &numa_priv
->proc_maps
;
1441 struct vm_area_struct
*vma
= v
;
1442 struct numa_maps
*md
= &numa_priv
->md
;
1443 struct file
*file
= vma
->vm_file
;
1444 struct mm_struct
*mm
= vma
->vm_mm
;
1445 struct mm_walk walk
= {};
1446 struct mempolicy
*pol
;
1453 /* Ensure we start with an empty set of numa_maps statistics. */
1454 memset(md
, 0, sizeof(*md
));
1458 walk
.hugetlb_entry
= gather_hugetbl_stats
;
1459 walk
.pmd_entry
= gather_pte_stats
;
1463 pol
= __get_vma_policy(vma
, vma
->vm_start
);
1465 mpol_to_str(buffer
, sizeof(buffer
), pol
);
1468 mpol_to_str(buffer
, sizeof(buffer
), proc_priv
->task_mempolicy
);
1471 seq_printf(m
, "%08lx %s", vma
->vm_start
, buffer
);
1474 seq_puts(m
, " file=");
1475 seq_path(m
, &file
->f_path
, "\n\t= ");
1476 } else if (vma
->vm_start
<= mm
->brk
&& vma
->vm_end
>= mm
->start_brk
) {
1477 seq_puts(m
, " heap");
1479 pid_t tid
= pid_of_stack(proc_priv
, vma
, is_pid
);
1482 * Thread stack in /proc/PID/task/TID/maps or
1483 * the main process stack.
1485 if (!is_pid
|| (vma
->vm_start
<= mm
->start_stack
&&
1486 vma
->vm_end
>= mm
->start_stack
))
1487 seq_puts(m
, " stack");
1489 seq_printf(m
, " stack:%d", tid
);
1493 if (is_vm_hugetlb_page(vma
))
1494 seq_puts(m
, " huge");
1496 walk_page_range(vma
->vm_start
, vma
->vm_end
, &walk
);
1502 seq_printf(m
, " anon=%lu", md
->anon
);
1505 seq_printf(m
, " dirty=%lu", md
->dirty
);
1507 if (md
->pages
!= md
->anon
&& md
->pages
!= md
->dirty
)
1508 seq_printf(m
, " mapped=%lu", md
->pages
);
1510 if (md
->mapcount_max
> 1)
1511 seq_printf(m
, " mapmax=%lu", md
->mapcount_max
);
1514 seq_printf(m
, " swapcache=%lu", md
->swapcache
);
1516 if (md
->active
< md
->pages
&& !is_vm_hugetlb_page(vma
))
1517 seq_printf(m
, " active=%lu", md
->active
);
1520 seq_printf(m
, " writeback=%lu", md
->writeback
);
1522 for_each_node_state(nid
, N_MEMORY
)
1524 seq_printf(m
, " N%d=%lu", nid
, md
->node
[nid
]);
1527 m_cache_vma(m
, vma
);
1531 static int show_pid_numa_map(struct seq_file
*m
, void *v
)
1533 return show_numa_map(m
, v
, 1);
1536 static int show_tid_numa_map(struct seq_file
*m
, void *v
)
1538 return show_numa_map(m
, v
, 0);
1541 static const struct seq_operations proc_pid_numa_maps_op
= {
1545 .show
= show_pid_numa_map
,
1548 static const struct seq_operations proc_tid_numa_maps_op
= {
1552 .show
= show_tid_numa_map
,
1555 static int numa_maps_open(struct inode
*inode
, struct file
*file
,
1556 const struct seq_operations
*ops
)
1558 return proc_maps_open(inode
, file
, ops
,
1559 sizeof(struct numa_maps_private
));
1562 static int pid_numa_maps_open(struct inode
*inode
, struct file
*file
)
1564 return numa_maps_open(inode
, file
, &proc_pid_numa_maps_op
);
1567 static int tid_numa_maps_open(struct inode
*inode
, struct file
*file
)
1569 return numa_maps_open(inode
, file
, &proc_tid_numa_maps_op
);
1572 const struct file_operations proc_pid_numa_maps_operations
= {
1573 .open
= pid_numa_maps_open
,
1575 .llseek
= seq_lseek
,
1576 .release
= proc_map_release
,
1579 const struct file_operations proc_tid_numa_maps_operations
= {
1580 .open
= tid_numa_maps_open
,
1582 .llseek
= seq_lseek
,
1583 .release
= proc_map_release
,
1585 #endif /* CONFIG_NUMA */