1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/pagewalk.h>
3 #include <linux/vmacache.h>
4 #include <linux/hugetlb.h>
5 #include <linux/huge_mm.h>
6 #include <linux/mount.h>
7 #include <linux/seq_file.h>
8 #include <linux/highmem.h>
9 #include <linux/ptrace.h>
10 #include <linux/slab.h>
11 #include <linux/pagemap.h>
12 #include <linux/mempolicy.h>
13 #include <linux/rmap.h>
14 #include <linux/swap.h>
15 #include <linux/sched/mm.h>
16 #include <linux/swapops.h>
17 #include <linux/mmu_notifier.h>
18 #include <linux/page_idle.h>
19 #include <linux/shmem_fs.h>
20 #include <linux/uaccess.h>
21 #include <linux/pkeys.h>
25 #include <asm/tlbflush.h>
28 #define SEQ_PUT_DEC(str, val) \
29 seq_put_decimal_ull_width(m, str, (val) << (PAGE_SHIFT-10), 8)
30 void task_mem(struct seq_file
*m
, struct mm_struct
*mm
)
32 unsigned long text
, lib
, swap
, anon
, file
, shmem
;
33 unsigned long hiwater_vm
, total_vm
, hiwater_rss
, total_rss
;
35 anon
= get_mm_counter(mm
, MM_ANONPAGES
);
36 file
= get_mm_counter(mm
, MM_FILEPAGES
);
37 shmem
= get_mm_counter(mm
, MM_SHMEMPAGES
);
40 * Note: to minimize their overhead, mm maintains hiwater_vm and
41 * hiwater_rss only when about to *lower* total_vm or rss. Any
42 * collector of these hiwater stats must therefore get total_vm
43 * and rss too, which will usually be the higher. Barriers? not
44 * worth the effort, such snapshots can always be inconsistent.
46 hiwater_vm
= total_vm
= mm
->total_vm
;
47 if (hiwater_vm
< mm
->hiwater_vm
)
48 hiwater_vm
= mm
->hiwater_vm
;
49 hiwater_rss
= total_rss
= anon
+ file
+ shmem
;
50 if (hiwater_rss
< mm
->hiwater_rss
)
51 hiwater_rss
= mm
->hiwater_rss
;
53 /* split executable areas between text and lib */
54 text
= PAGE_ALIGN(mm
->end_code
) - (mm
->start_code
& PAGE_MASK
);
55 text
= min(text
, mm
->exec_vm
<< PAGE_SHIFT
);
56 lib
= (mm
->exec_vm
<< PAGE_SHIFT
) - text
;
58 swap
= get_mm_counter(mm
, MM_SWAPENTS
);
59 SEQ_PUT_DEC("VmPeak:\t", hiwater_vm
);
60 SEQ_PUT_DEC(" kB\nVmSize:\t", total_vm
);
61 SEQ_PUT_DEC(" kB\nVmLck:\t", mm
->locked_vm
);
62 SEQ_PUT_DEC(" kB\nVmPin:\t", atomic64_read(&mm
->pinned_vm
));
63 SEQ_PUT_DEC(" kB\nVmHWM:\t", hiwater_rss
);
64 SEQ_PUT_DEC(" kB\nVmRSS:\t", total_rss
);
65 SEQ_PUT_DEC(" kB\nRssAnon:\t", anon
);
66 SEQ_PUT_DEC(" kB\nRssFile:\t", file
);
67 SEQ_PUT_DEC(" kB\nRssShmem:\t", shmem
);
68 SEQ_PUT_DEC(" kB\nVmData:\t", mm
->data_vm
);
69 SEQ_PUT_DEC(" kB\nVmStk:\t", mm
->stack_vm
);
70 seq_put_decimal_ull_width(m
,
71 " kB\nVmExe:\t", text
>> 10, 8);
72 seq_put_decimal_ull_width(m
,
73 " kB\nVmLib:\t", lib
>> 10, 8);
74 seq_put_decimal_ull_width(m
,
75 " kB\nVmPTE:\t", mm_pgtables_bytes(mm
) >> 10, 8);
76 SEQ_PUT_DEC(" kB\nVmSwap:\t", swap
);
78 hugetlb_report_usage(m
, mm
);
82 unsigned long task_vsize(struct mm_struct
*mm
)
84 return PAGE_SIZE
* mm
->total_vm
;
87 unsigned long task_statm(struct mm_struct
*mm
,
88 unsigned long *shared
, unsigned long *text
,
89 unsigned long *data
, unsigned long *resident
)
91 *shared
= get_mm_counter(mm
, MM_FILEPAGES
) +
92 get_mm_counter(mm
, MM_SHMEMPAGES
);
93 *text
= (PAGE_ALIGN(mm
->end_code
) - (mm
->start_code
& PAGE_MASK
))
95 *data
= mm
->data_vm
+ mm
->stack_vm
;
96 *resident
= *shared
+ get_mm_counter(mm
, MM_ANONPAGES
);
102 * Save get_task_policy() for show_numa_map().
104 static void hold_task_mempolicy(struct proc_maps_private
*priv
)
106 struct task_struct
*task
= priv
->task
;
109 priv
->task_mempolicy
= get_task_policy(task
);
110 mpol_get(priv
->task_mempolicy
);
113 static void release_task_mempolicy(struct proc_maps_private
*priv
)
115 mpol_put(priv
->task_mempolicy
);
118 static void hold_task_mempolicy(struct proc_maps_private
*priv
)
121 static void release_task_mempolicy(struct proc_maps_private
*priv
)
126 static void vma_stop(struct proc_maps_private
*priv
)
128 struct mm_struct
*mm
= priv
->mm
;
130 release_task_mempolicy(priv
);
131 up_read(&mm
->mmap_sem
);
135 static struct vm_area_struct
*
136 m_next_vma(struct proc_maps_private
*priv
, struct vm_area_struct
*vma
)
138 if (vma
== priv
->tail_vma
)
140 return vma
->vm_next
?: priv
->tail_vma
;
143 static void m_cache_vma(struct seq_file
*m
, struct vm_area_struct
*vma
)
145 if (m
->count
< m
->size
) /* vma is copied successfully */
146 m
->version
= m_next_vma(m
->private, vma
) ? vma
->vm_end
: -1UL;
149 static void *m_start(struct seq_file
*m
, loff_t
*ppos
)
151 struct proc_maps_private
*priv
= m
->private;
152 unsigned long last_addr
= m
->version
;
153 struct mm_struct
*mm
;
154 struct vm_area_struct
*vma
;
155 unsigned int pos
= *ppos
;
157 /* See m_cache_vma(). Zero at the start or after lseek. */
158 if (last_addr
== -1UL)
161 priv
->task
= get_proc_task(priv
->inode
);
163 return ERR_PTR(-ESRCH
);
166 if (!mm
|| !mmget_not_zero(mm
))
169 if (down_read_killable(&mm
->mmap_sem
)) {
171 return ERR_PTR(-EINTR
);
174 hold_task_mempolicy(priv
);
175 priv
->tail_vma
= get_gate_vma(mm
);
178 vma
= find_vma(mm
, last_addr
- 1);
179 if (vma
&& vma
->vm_start
<= last_addr
)
180 vma
= m_next_vma(priv
, vma
);
186 if (pos
< mm
->map_count
) {
187 for (vma
= mm
->mmap
; pos
; pos
--) {
188 m
->version
= vma
->vm_start
;
194 /* we do not bother to update m->version in this case */
195 if (pos
== mm
->map_count
&& priv
->tail_vma
)
196 return priv
->tail_vma
;
202 static void *m_next(struct seq_file
*m
, void *v
, loff_t
*pos
)
204 struct proc_maps_private
*priv
= m
->private;
205 struct vm_area_struct
*next
;
208 next
= m_next_vma(priv
, v
);
214 static void m_stop(struct seq_file
*m
, void *v
)
216 struct proc_maps_private
*priv
= m
->private;
218 if (!IS_ERR_OR_NULL(v
))
221 put_task_struct(priv
->task
);
226 static int proc_maps_open(struct inode
*inode
, struct file
*file
,
227 const struct seq_operations
*ops
, int psize
)
229 struct proc_maps_private
*priv
= __seq_open_private(file
, ops
, psize
);
235 priv
->mm
= proc_mem_open(inode
, PTRACE_MODE_READ
);
236 if (IS_ERR(priv
->mm
)) {
237 int err
= PTR_ERR(priv
->mm
);
239 seq_release_private(inode
, file
);
246 static int proc_map_release(struct inode
*inode
, struct file
*file
)
248 struct seq_file
*seq
= file
->private_data
;
249 struct proc_maps_private
*priv
= seq
->private;
254 return seq_release_private(inode
, file
);
257 static int do_maps_open(struct inode
*inode
, struct file
*file
,
258 const struct seq_operations
*ops
)
260 return proc_maps_open(inode
, file
, ops
,
261 sizeof(struct proc_maps_private
));
265 * Indicate if the VMA is a stack for the given task; for
266 * /proc/PID/maps that is the stack of the main task.
268 static int is_stack(struct vm_area_struct
*vma
)
271 * We make no effort to guess what a given thread considers to be
272 * its "stack". It's not even well-defined for programs written
275 return vma
->vm_start
<= vma
->vm_mm
->start_stack
&&
276 vma
->vm_end
>= vma
->vm_mm
->start_stack
;
279 static void show_vma_header_prefix(struct seq_file
*m
,
280 unsigned long start
, unsigned long end
,
281 vm_flags_t flags
, unsigned long long pgoff
,
282 dev_t dev
, unsigned long ino
)
284 seq_setwidth(m
, 25 + sizeof(void *) * 6 - 1);
285 seq_put_hex_ll(m
, NULL
, start
, 8);
286 seq_put_hex_ll(m
, "-", end
, 8);
288 seq_putc(m
, flags
& VM_READ
? 'r' : '-');
289 seq_putc(m
, flags
& VM_WRITE
? 'w' : '-');
290 seq_putc(m
, flags
& VM_EXEC
? 'x' : '-');
291 seq_putc(m
, flags
& VM_MAYSHARE
? 's' : 'p');
292 seq_put_hex_ll(m
, " ", pgoff
, 8);
293 seq_put_hex_ll(m
, " ", MAJOR(dev
), 2);
294 seq_put_hex_ll(m
, ":", MINOR(dev
), 2);
295 seq_put_decimal_ull(m
, " ", ino
);
300 show_map_vma(struct seq_file
*m
, struct vm_area_struct
*vma
)
302 struct mm_struct
*mm
= vma
->vm_mm
;
303 struct file
*file
= vma
->vm_file
;
304 vm_flags_t flags
= vma
->vm_flags
;
305 unsigned long ino
= 0;
306 unsigned long long pgoff
= 0;
307 unsigned long start
, end
;
309 const char *name
= NULL
;
312 struct inode
*inode
= file_inode(vma
->vm_file
);
313 dev
= inode
->i_sb
->s_dev
;
315 pgoff
= ((loff_t
)vma
->vm_pgoff
) << PAGE_SHIFT
;
318 start
= vma
->vm_start
;
320 show_vma_header_prefix(m
, start
, end
, flags
, pgoff
, dev
, ino
);
323 * Print the dentry name for named mappings, and a
324 * special [heap] marker for the heap:
328 seq_file_path(m
, file
, "\n");
332 if (vma
->vm_ops
&& vma
->vm_ops
->name
) {
333 name
= vma
->vm_ops
->name(vma
);
338 name
= arch_vma_name(vma
);
345 if (vma
->vm_start
<= mm
->brk
&&
346 vma
->vm_end
>= mm
->start_brk
) {
363 static int show_map(struct seq_file
*m
, void *v
)
370 static const struct seq_operations proc_pid_maps_op
= {
377 static int pid_maps_open(struct inode
*inode
, struct file
*file
)
379 return do_maps_open(inode
, file
, &proc_pid_maps_op
);
382 const struct file_operations proc_pid_maps_operations
= {
383 .open
= pid_maps_open
,
386 .release
= proc_map_release
,
390 * Proportional Set Size(PSS): my share of RSS.
392 * PSS of a process is the count of pages it has in memory, where each
393 * page is divided by the number of processes sharing it. So if a
394 * process has 1000 pages all to itself, and 1000 shared with one other
395 * process, its PSS will be 1500.
397 * To keep (accumulated) division errors low, we adopt a 64bit
398 * fixed-point pss counter to minimize division errors. So (pss >>
399 * PSS_SHIFT) would be the real byte count.
401 * A shift of 12 before division means (assuming 4K page size):
402 * - 1M 3-user-pages add up to 8KB errors;
403 * - supports mapcount up to 2^24, or 16M;
404 * - supports PSS up to 2^52 bytes, or 4PB.
408 #ifdef CONFIG_PROC_PAGE_MONITOR
409 struct mem_size_stats
{
410 unsigned long resident
;
411 unsigned long shared_clean
;
412 unsigned long shared_dirty
;
413 unsigned long private_clean
;
414 unsigned long private_dirty
;
415 unsigned long referenced
;
416 unsigned long anonymous
;
417 unsigned long lazyfree
;
418 unsigned long anonymous_thp
;
419 unsigned long shmem_thp
;
420 unsigned long file_thp
;
422 unsigned long shared_hugetlb
;
423 unsigned long private_hugetlb
;
430 bool check_shmem_swap
;
433 static void smaps_page_accumulate(struct mem_size_stats
*mss
,
434 struct page
*page
, unsigned long size
, unsigned long pss
,
435 bool dirty
, bool locked
, bool private)
440 mss
->pss_anon
+= pss
;
441 else if (PageSwapBacked(page
))
442 mss
->pss_shmem
+= pss
;
444 mss
->pss_file
+= pss
;
447 mss
->pss_locked
+= pss
;
449 if (dirty
|| PageDirty(page
)) {
451 mss
->private_dirty
+= size
;
453 mss
->shared_dirty
+= size
;
456 mss
->private_clean
+= size
;
458 mss
->shared_clean
+= size
;
462 static void smaps_account(struct mem_size_stats
*mss
, struct page
*page
,
463 bool compound
, bool young
, bool dirty
, bool locked
)
465 int i
, nr
= compound
? compound_nr(page
) : 1;
466 unsigned long size
= nr
* PAGE_SIZE
;
469 * First accumulate quantities that depend only on |size| and the type
470 * of the compound page.
472 if (PageAnon(page
)) {
473 mss
->anonymous
+= size
;
474 if (!PageSwapBacked(page
) && !dirty
&& !PageDirty(page
))
475 mss
->lazyfree
+= size
;
478 mss
->resident
+= size
;
479 /* Accumulate the size in pages that have been accessed. */
480 if (young
|| page_is_young(page
) || PageReferenced(page
))
481 mss
->referenced
+= size
;
484 * Then accumulate quantities that may depend on sharing, or that may
485 * differ page-by-page.
487 * page_count(page) == 1 guarantees the page is mapped exactly once.
488 * If any subpage of the compound page mapped with PTE it would elevate
491 if (page_count(page
) == 1) {
492 smaps_page_accumulate(mss
, page
, size
, size
<< PSS_SHIFT
, dirty
,
496 for (i
= 0; i
< nr
; i
++, page
++) {
497 int mapcount
= page_mapcount(page
);
498 unsigned long pss
= PAGE_SIZE
<< PSS_SHIFT
;
501 smaps_page_accumulate(mss
, page
, PAGE_SIZE
, pss
, dirty
, locked
,
507 static int smaps_pte_hole(unsigned long addr
, unsigned long end
,
508 __always_unused
int depth
, struct mm_walk
*walk
)
510 struct mem_size_stats
*mss
= walk
->private;
512 mss
->swap
+= shmem_partial_swap_usage(
513 walk
->vma
->vm_file
->f_mapping
, addr
, end
);
518 #define smaps_pte_hole NULL
519 #endif /* CONFIG_SHMEM */
521 static void smaps_pte_entry(pte_t
*pte
, unsigned long addr
,
522 struct mm_walk
*walk
)
524 struct mem_size_stats
*mss
= walk
->private;
525 struct vm_area_struct
*vma
= walk
->vma
;
526 bool locked
= !!(vma
->vm_flags
& VM_LOCKED
);
527 struct page
*page
= NULL
;
529 if (pte_present(*pte
)) {
530 page
= vm_normal_page(vma
, addr
, *pte
);
531 } else if (is_swap_pte(*pte
)) {
532 swp_entry_t swpent
= pte_to_swp_entry(*pte
);
534 if (!non_swap_entry(swpent
)) {
537 mss
->swap
+= PAGE_SIZE
;
538 mapcount
= swp_swapcount(swpent
);
540 u64 pss_delta
= (u64
)PAGE_SIZE
<< PSS_SHIFT
;
542 do_div(pss_delta
, mapcount
);
543 mss
->swap_pss
+= pss_delta
;
545 mss
->swap_pss
+= (u64
)PAGE_SIZE
<< PSS_SHIFT
;
547 } else if (is_migration_entry(swpent
))
548 page
= migration_entry_to_page(swpent
);
549 else if (is_device_private_entry(swpent
))
550 page
= device_private_entry_to_page(swpent
);
551 } else if (unlikely(IS_ENABLED(CONFIG_SHMEM
) && mss
->check_shmem_swap
552 && pte_none(*pte
))) {
553 page
= find_get_entry(vma
->vm_file
->f_mapping
,
554 linear_page_index(vma
, addr
));
558 if (xa_is_value(page
))
559 mss
->swap
+= PAGE_SIZE
;
569 smaps_account(mss
, page
, false, pte_young(*pte
), pte_dirty(*pte
), locked
);
572 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
573 static void smaps_pmd_entry(pmd_t
*pmd
, unsigned long addr
,
574 struct mm_walk
*walk
)
576 struct mem_size_stats
*mss
= walk
->private;
577 struct vm_area_struct
*vma
= walk
->vma
;
578 bool locked
= !!(vma
->vm_flags
& VM_LOCKED
);
581 /* FOLL_DUMP will return -EFAULT on huge zero page */
582 page
= follow_trans_huge_pmd(vma
, addr
, pmd
, FOLL_DUMP
);
583 if (IS_ERR_OR_NULL(page
))
586 mss
->anonymous_thp
+= HPAGE_PMD_SIZE
;
587 else if (PageSwapBacked(page
))
588 mss
->shmem_thp
+= HPAGE_PMD_SIZE
;
589 else if (is_zone_device_page(page
))
592 mss
->file_thp
+= HPAGE_PMD_SIZE
;
593 smaps_account(mss
, page
, true, pmd_young(*pmd
), pmd_dirty(*pmd
), locked
);
596 static void smaps_pmd_entry(pmd_t
*pmd
, unsigned long addr
,
597 struct mm_walk
*walk
)
602 static int smaps_pte_range(pmd_t
*pmd
, unsigned long addr
, unsigned long end
,
603 struct mm_walk
*walk
)
605 struct vm_area_struct
*vma
= walk
->vma
;
609 ptl
= pmd_trans_huge_lock(pmd
, vma
);
611 if (pmd_present(*pmd
))
612 smaps_pmd_entry(pmd
, addr
, walk
);
617 if (pmd_trans_unstable(pmd
))
620 * The mmap_sem held all the way back in m_start() is what
621 * keeps khugepaged out of here and from collapsing things
624 pte
= pte_offset_map_lock(vma
->vm_mm
, pmd
, addr
, &ptl
);
625 for (; addr
!= end
; pte
++, addr
+= PAGE_SIZE
)
626 smaps_pte_entry(pte
, addr
, walk
);
627 pte_unmap_unlock(pte
- 1, ptl
);
633 static void show_smap_vma_flags(struct seq_file
*m
, struct vm_area_struct
*vma
)
636 * Don't forget to update Documentation/ on changes.
638 static const char mnemonics
[BITS_PER_LONG
][2] = {
640 * In case if we meet a flag we don't know about.
642 [0 ... (BITS_PER_LONG
-1)] = "??",
644 [ilog2(VM_READ
)] = "rd",
645 [ilog2(VM_WRITE
)] = "wr",
646 [ilog2(VM_EXEC
)] = "ex",
647 [ilog2(VM_SHARED
)] = "sh",
648 [ilog2(VM_MAYREAD
)] = "mr",
649 [ilog2(VM_MAYWRITE
)] = "mw",
650 [ilog2(VM_MAYEXEC
)] = "me",
651 [ilog2(VM_MAYSHARE
)] = "ms",
652 [ilog2(VM_GROWSDOWN
)] = "gd",
653 [ilog2(VM_PFNMAP
)] = "pf",
654 [ilog2(VM_DENYWRITE
)] = "dw",
655 #ifdef CONFIG_X86_INTEL_MPX
656 [ilog2(VM_MPX
)] = "mp",
658 [ilog2(VM_LOCKED
)] = "lo",
659 [ilog2(VM_IO
)] = "io",
660 [ilog2(VM_SEQ_READ
)] = "sr",
661 [ilog2(VM_RAND_READ
)] = "rr",
662 [ilog2(VM_DONTCOPY
)] = "dc",
663 [ilog2(VM_DONTEXPAND
)] = "de",
664 [ilog2(VM_ACCOUNT
)] = "ac",
665 [ilog2(VM_NORESERVE
)] = "nr",
666 [ilog2(VM_HUGETLB
)] = "ht",
667 [ilog2(VM_SYNC
)] = "sf",
668 [ilog2(VM_ARCH_1
)] = "ar",
669 [ilog2(VM_WIPEONFORK
)] = "wf",
670 [ilog2(VM_DONTDUMP
)] = "dd",
671 #ifdef CONFIG_MEM_SOFT_DIRTY
672 [ilog2(VM_SOFTDIRTY
)] = "sd",
674 [ilog2(VM_MIXEDMAP
)] = "mm",
675 [ilog2(VM_HUGEPAGE
)] = "hg",
676 [ilog2(VM_NOHUGEPAGE
)] = "nh",
677 [ilog2(VM_MERGEABLE
)] = "mg",
678 [ilog2(VM_UFFD_MISSING
)]= "um",
679 [ilog2(VM_UFFD_WP
)] = "uw",
680 #ifdef CONFIG_ARCH_HAS_PKEYS
681 /* These come out via ProtectionKey: */
682 [ilog2(VM_PKEY_BIT0
)] = "",
683 [ilog2(VM_PKEY_BIT1
)] = "",
684 [ilog2(VM_PKEY_BIT2
)] = "",
685 [ilog2(VM_PKEY_BIT3
)] = "",
687 [ilog2(VM_PKEY_BIT4
)] = "",
689 #endif /* CONFIG_ARCH_HAS_PKEYS */
693 seq_puts(m
, "VmFlags: ");
694 for (i
= 0; i
< BITS_PER_LONG
; i
++) {
695 if (!mnemonics
[i
][0])
697 if (vma
->vm_flags
& (1UL << i
)) {
698 seq_putc(m
, mnemonics
[i
][0]);
699 seq_putc(m
, mnemonics
[i
][1]);
706 #ifdef CONFIG_HUGETLB_PAGE
707 static int smaps_hugetlb_range(pte_t
*pte
, unsigned long hmask
,
708 unsigned long addr
, unsigned long end
,
709 struct mm_walk
*walk
)
711 struct mem_size_stats
*mss
= walk
->private;
712 struct vm_area_struct
*vma
= walk
->vma
;
713 struct page
*page
= NULL
;
715 if (pte_present(*pte
)) {
716 page
= vm_normal_page(vma
, addr
, *pte
);
717 } else if (is_swap_pte(*pte
)) {
718 swp_entry_t swpent
= pte_to_swp_entry(*pte
);
720 if (is_migration_entry(swpent
))
721 page
= migration_entry_to_page(swpent
);
722 else if (is_device_private_entry(swpent
))
723 page
= device_private_entry_to_page(swpent
);
726 int mapcount
= page_mapcount(page
);
729 mss
->shared_hugetlb
+= huge_page_size(hstate_vma(vma
));
731 mss
->private_hugetlb
+= huge_page_size(hstate_vma(vma
));
736 #define smaps_hugetlb_range NULL
737 #endif /* HUGETLB_PAGE */
739 static const struct mm_walk_ops smaps_walk_ops
= {
740 .pmd_entry
= smaps_pte_range
,
741 .hugetlb_entry
= smaps_hugetlb_range
,
744 static const struct mm_walk_ops smaps_shmem_walk_ops
= {
745 .pmd_entry
= smaps_pte_range
,
746 .hugetlb_entry
= smaps_hugetlb_range
,
747 .pte_hole
= smaps_pte_hole
,
750 static void smap_gather_stats(struct vm_area_struct
*vma
,
751 struct mem_size_stats
*mss
)
754 /* In case of smaps_rollup, reset the value from previous vma */
755 mss
->check_shmem_swap
= false;
756 if (vma
->vm_file
&& shmem_mapping(vma
->vm_file
->f_mapping
)) {
758 * For shared or readonly shmem mappings we know that all
759 * swapped out pages belong to the shmem object, and we can
760 * obtain the swap value much more efficiently. For private
761 * writable mappings, we might have COW pages that are
762 * not affected by the parent swapped out pages of the shmem
763 * object, so we have to distinguish them during the page walk.
764 * Unless we know that the shmem object (or the part mapped by
765 * our VMA) has no swapped out pages at all.
767 unsigned long shmem_swapped
= shmem_swap_usage(vma
);
769 if (!shmem_swapped
|| (vma
->vm_flags
& VM_SHARED
) ||
770 !(vma
->vm_flags
& VM_WRITE
)) {
771 mss
->swap
+= shmem_swapped
;
773 mss
->check_shmem_swap
= true;
774 walk_page_vma(vma
, &smaps_shmem_walk_ops
, mss
);
779 /* mmap_sem is held in m_start */
780 walk_page_vma(vma
, &smaps_walk_ops
, mss
);
783 #define SEQ_PUT_DEC(str, val) \
784 seq_put_decimal_ull_width(m, str, (val) >> 10, 8)
786 /* Show the contents common for smaps and smaps_rollup */
787 static void __show_smap(struct seq_file
*m
, const struct mem_size_stats
*mss
,
790 SEQ_PUT_DEC("Rss: ", mss
->resident
);
791 SEQ_PUT_DEC(" kB\nPss: ", mss
->pss
>> PSS_SHIFT
);
794 * These are meaningful only for smaps_rollup, otherwise two of
795 * them are zero, and the other one is the same as Pss.
797 SEQ_PUT_DEC(" kB\nPss_Anon: ",
798 mss
->pss_anon
>> PSS_SHIFT
);
799 SEQ_PUT_DEC(" kB\nPss_File: ",
800 mss
->pss_file
>> PSS_SHIFT
);
801 SEQ_PUT_DEC(" kB\nPss_Shmem: ",
802 mss
->pss_shmem
>> PSS_SHIFT
);
804 SEQ_PUT_DEC(" kB\nShared_Clean: ", mss
->shared_clean
);
805 SEQ_PUT_DEC(" kB\nShared_Dirty: ", mss
->shared_dirty
);
806 SEQ_PUT_DEC(" kB\nPrivate_Clean: ", mss
->private_clean
);
807 SEQ_PUT_DEC(" kB\nPrivate_Dirty: ", mss
->private_dirty
);
808 SEQ_PUT_DEC(" kB\nReferenced: ", mss
->referenced
);
809 SEQ_PUT_DEC(" kB\nAnonymous: ", mss
->anonymous
);
810 SEQ_PUT_DEC(" kB\nLazyFree: ", mss
->lazyfree
);
811 SEQ_PUT_DEC(" kB\nAnonHugePages: ", mss
->anonymous_thp
);
812 SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss
->shmem_thp
);
813 SEQ_PUT_DEC(" kB\nFilePmdMapped: ", mss
->file_thp
);
814 SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss
->shared_hugetlb
);
815 seq_put_decimal_ull_width(m
, " kB\nPrivate_Hugetlb: ",
816 mss
->private_hugetlb
>> 10, 7);
817 SEQ_PUT_DEC(" kB\nSwap: ", mss
->swap
);
818 SEQ_PUT_DEC(" kB\nSwapPss: ",
819 mss
->swap_pss
>> PSS_SHIFT
);
820 SEQ_PUT_DEC(" kB\nLocked: ",
821 mss
->pss_locked
>> PSS_SHIFT
);
822 seq_puts(m
, " kB\n");
825 static int show_smap(struct seq_file
*m
, void *v
)
827 struct vm_area_struct
*vma
= v
;
828 struct mem_size_stats mss
;
830 memset(&mss
, 0, sizeof(mss
));
832 smap_gather_stats(vma
, &mss
);
834 show_map_vma(m
, vma
);
836 SEQ_PUT_DEC("Size: ", vma
->vm_end
- vma
->vm_start
);
837 SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma
));
838 SEQ_PUT_DEC(" kB\nMMUPageSize: ", vma_mmu_pagesize(vma
));
839 seq_puts(m
, " kB\n");
841 __show_smap(m
, &mss
, false);
843 seq_printf(m
, "THPeligible: %d\n",
844 transparent_hugepage_enabled(vma
));
846 if (arch_pkeys_enabled())
847 seq_printf(m
, "ProtectionKey: %8u\n", vma_pkey(vma
));
848 show_smap_vma_flags(m
, vma
);
855 static int show_smaps_rollup(struct seq_file
*m
, void *v
)
857 struct proc_maps_private
*priv
= m
->private;
858 struct mem_size_stats mss
;
859 struct mm_struct
*mm
;
860 struct vm_area_struct
*vma
;
861 unsigned long last_vma_end
= 0;
864 priv
->task
= get_proc_task(priv
->inode
);
869 if (!mm
|| !mmget_not_zero(mm
)) {
874 memset(&mss
, 0, sizeof(mss
));
876 ret
= down_read_killable(&mm
->mmap_sem
);
880 hold_task_mempolicy(priv
);
882 for (vma
= priv
->mm
->mmap
; vma
; vma
= vma
->vm_next
) {
883 smap_gather_stats(vma
, &mss
);
884 last_vma_end
= vma
->vm_end
;
887 show_vma_header_prefix(m
, priv
->mm
->mmap
->vm_start
,
888 last_vma_end
, 0, 0, 0, 0);
890 seq_puts(m
, "[rollup]\n");
892 __show_smap(m
, &mss
, true);
894 release_task_mempolicy(priv
);
895 up_read(&mm
->mmap_sem
);
900 put_task_struct(priv
->task
);
907 static const struct seq_operations proc_pid_smaps_op
= {
914 static int pid_smaps_open(struct inode
*inode
, struct file
*file
)
916 return do_maps_open(inode
, file
, &proc_pid_smaps_op
);
919 static int smaps_rollup_open(struct inode
*inode
, struct file
*file
)
922 struct proc_maps_private
*priv
;
924 priv
= kzalloc(sizeof(*priv
), GFP_KERNEL_ACCOUNT
);
928 ret
= single_open(file
, show_smaps_rollup
, priv
);
933 priv
->mm
= proc_mem_open(inode
, PTRACE_MODE_READ
);
934 if (IS_ERR(priv
->mm
)) {
935 ret
= PTR_ERR(priv
->mm
);
937 single_release(inode
, file
);
948 static int smaps_rollup_release(struct inode
*inode
, struct file
*file
)
950 struct seq_file
*seq
= file
->private_data
;
951 struct proc_maps_private
*priv
= seq
->private;
957 return single_release(inode
, file
);
960 const struct file_operations proc_pid_smaps_operations
= {
961 .open
= pid_smaps_open
,
964 .release
= proc_map_release
,
967 const struct file_operations proc_pid_smaps_rollup_operations
= {
968 .open
= smaps_rollup_open
,
971 .release
= smaps_rollup_release
,
974 enum clear_refs_types
{
978 CLEAR_REFS_SOFT_DIRTY
,
979 CLEAR_REFS_MM_HIWATER_RSS
,
983 struct clear_refs_private
{
984 enum clear_refs_types type
;
987 #ifdef CONFIG_MEM_SOFT_DIRTY
988 static inline void clear_soft_dirty(struct vm_area_struct
*vma
,
989 unsigned long addr
, pte_t
*pte
)
992 * The soft-dirty tracker uses #PF-s to catch writes
993 * to pages, so write-protect the pte as well. See the
994 * Documentation/admin-guide/mm/soft-dirty.rst for full description
995 * of how soft-dirty works.
999 if (pte_present(ptent
)) {
1002 old_pte
= ptep_modify_prot_start(vma
, addr
, pte
);
1003 ptent
= pte_wrprotect(old_pte
);
1004 ptent
= pte_clear_soft_dirty(ptent
);
1005 ptep_modify_prot_commit(vma
, addr
, pte
, old_pte
, ptent
);
1006 } else if (is_swap_pte(ptent
)) {
1007 ptent
= pte_swp_clear_soft_dirty(ptent
);
1008 set_pte_at(vma
->vm_mm
, addr
, pte
, ptent
);
1012 static inline void clear_soft_dirty(struct vm_area_struct
*vma
,
1013 unsigned long addr
, pte_t
*pte
)
1018 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
1019 static inline void clear_soft_dirty_pmd(struct vm_area_struct
*vma
,
1020 unsigned long addr
, pmd_t
*pmdp
)
1022 pmd_t old
, pmd
= *pmdp
;
1024 if (pmd_present(pmd
)) {
1025 /* See comment in change_huge_pmd() */
1026 old
= pmdp_invalidate(vma
, addr
, pmdp
);
1028 pmd
= pmd_mkdirty(pmd
);
1030 pmd
= pmd_mkyoung(pmd
);
1032 pmd
= pmd_wrprotect(pmd
);
1033 pmd
= pmd_clear_soft_dirty(pmd
);
1035 set_pmd_at(vma
->vm_mm
, addr
, pmdp
, pmd
);
1036 } else if (is_migration_entry(pmd_to_swp_entry(pmd
))) {
1037 pmd
= pmd_swp_clear_soft_dirty(pmd
);
1038 set_pmd_at(vma
->vm_mm
, addr
, pmdp
, pmd
);
1042 static inline void clear_soft_dirty_pmd(struct vm_area_struct
*vma
,
1043 unsigned long addr
, pmd_t
*pmdp
)
1048 static int clear_refs_pte_range(pmd_t
*pmd
, unsigned long addr
,
1049 unsigned long end
, struct mm_walk
*walk
)
1051 struct clear_refs_private
*cp
= walk
->private;
1052 struct vm_area_struct
*vma
= walk
->vma
;
1057 ptl
= pmd_trans_huge_lock(pmd
, vma
);
1059 if (cp
->type
== CLEAR_REFS_SOFT_DIRTY
) {
1060 clear_soft_dirty_pmd(vma
, addr
, pmd
);
1064 if (!pmd_present(*pmd
))
1067 page
= pmd_page(*pmd
);
1069 /* Clear accessed and referenced bits. */
1070 pmdp_test_and_clear_young(vma
, addr
, pmd
);
1071 test_and_clear_page_young(page
);
1072 ClearPageReferenced(page
);
1078 if (pmd_trans_unstable(pmd
))
1081 pte
= pte_offset_map_lock(vma
->vm_mm
, pmd
, addr
, &ptl
);
1082 for (; addr
!= end
; pte
++, addr
+= PAGE_SIZE
) {
1085 if (cp
->type
== CLEAR_REFS_SOFT_DIRTY
) {
1086 clear_soft_dirty(vma
, addr
, pte
);
1090 if (!pte_present(ptent
))
1093 page
= vm_normal_page(vma
, addr
, ptent
);
1097 /* Clear accessed and referenced bits. */
1098 ptep_test_and_clear_young(vma
, addr
, pte
);
1099 test_and_clear_page_young(page
);
1100 ClearPageReferenced(page
);
1102 pte_unmap_unlock(pte
- 1, ptl
);
1107 static int clear_refs_test_walk(unsigned long start
, unsigned long end
,
1108 struct mm_walk
*walk
)
1110 struct clear_refs_private
*cp
= walk
->private;
1111 struct vm_area_struct
*vma
= walk
->vma
;
1113 if (vma
->vm_flags
& VM_PFNMAP
)
1117 * Writing 1 to /proc/pid/clear_refs affects all pages.
1118 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages.
1119 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages.
1120 * Writing 4 to /proc/pid/clear_refs affects all pages.
1122 if (cp
->type
== CLEAR_REFS_ANON
&& vma
->vm_file
)
1124 if (cp
->type
== CLEAR_REFS_MAPPED
&& !vma
->vm_file
)
1129 static const struct mm_walk_ops clear_refs_walk_ops
= {
1130 .pmd_entry
= clear_refs_pte_range
,
1131 .test_walk
= clear_refs_test_walk
,
1134 static ssize_t
clear_refs_write(struct file
*file
, const char __user
*buf
,
1135 size_t count
, loff_t
*ppos
)
1137 struct task_struct
*task
;
1138 char buffer
[PROC_NUMBUF
];
1139 struct mm_struct
*mm
;
1140 struct vm_area_struct
*vma
;
1141 enum clear_refs_types type
;
1142 struct mmu_gather tlb
;
1146 memset(buffer
, 0, sizeof(buffer
));
1147 if (count
> sizeof(buffer
) - 1)
1148 count
= sizeof(buffer
) - 1;
1149 if (copy_from_user(buffer
, buf
, count
))
1151 rv
= kstrtoint(strstrip(buffer
), 10, &itype
);
1154 type
= (enum clear_refs_types
)itype
;
1155 if (type
< CLEAR_REFS_ALL
|| type
>= CLEAR_REFS_LAST
)
1158 task
= get_proc_task(file_inode(file
));
1161 mm
= get_task_mm(task
);
1163 struct mmu_notifier_range range
;
1164 struct clear_refs_private cp
= {
1168 if (type
== CLEAR_REFS_MM_HIWATER_RSS
) {
1169 if (down_write_killable(&mm
->mmap_sem
)) {
1175 * Writing 5 to /proc/pid/clear_refs resets the peak
1176 * resident set size to this mm's current rss value.
1178 reset_mm_hiwater_rss(mm
);
1179 up_write(&mm
->mmap_sem
);
1183 if (down_read_killable(&mm
->mmap_sem
)) {
1187 tlb_gather_mmu(&tlb
, mm
, 0, -1);
1188 if (type
== CLEAR_REFS_SOFT_DIRTY
) {
1189 for (vma
= mm
->mmap
; vma
; vma
= vma
->vm_next
) {
1190 if (!(vma
->vm_flags
& VM_SOFTDIRTY
))
1192 up_read(&mm
->mmap_sem
);
1193 if (down_write_killable(&mm
->mmap_sem
)) {
1198 * Avoid to modify vma->vm_flags
1199 * without locked ops while the
1200 * coredump reads the vm_flags.
1202 if (!mmget_still_valid(mm
)) {
1204 * Silently return "count"
1205 * like if get_task_mm()
1206 * failed. FIXME: should this
1207 * function have returned
1208 * -ESRCH if get_task_mm()
1210 * get_proc_task() fails?
1212 up_write(&mm
->mmap_sem
);
1215 for (vma
= mm
->mmap
; vma
; vma
= vma
->vm_next
) {
1216 vma
->vm_flags
&= ~VM_SOFTDIRTY
;
1217 vma_set_page_prot(vma
);
1219 downgrade_write(&mm
->mmap_sem
);
1223 mmu_notifier_range_init(&range
, MMU_NOTIFY_SOFT_DIRTY
,
1224 0, NULL
, mm
, 0, -1UL);
1225 mmu_notifier_invalidate_range_start(&range
);
1227 walk_page_range(mm
, 0, mm
->highest_vm_end
, &clear_refs_walk_ops
,
1229 if (type
== CLEAR_REFS_SOFT_DIRTY
)
1230 mmu_notifier_invalidate_range_end(&range
);
1231 tlb_finish_mmu(&tlb
, 0, -1);
1232 up_read(&mm
->mmap_sem
);
1236 put_task_struct(task
);
1241 const struct file_operations proc_clear_refs_operations
= {
1242 .write
= clear_refs_write
,
1243 .llseek
= noop_llseek
,
1250 struct pagemapread
{
1251 int pos
, len
; /* units: PM_ENTRY_BYTES, not bytes */
1252 pagemap_entry_t
*buffer
;
1256 #define PAGEMAP_WALK_SIZE (PMD_SIZE)
1257 #define PAGEMAP_WALK_MASK (PMD_MASK)
1259 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t)
1260 #define PM_PFRAME_BITS 55
1261 #define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0)
1262 #define PM_SOFT_DIRTY BIT_ULL(55)
1263 #define PM_MMAP_EXCLUSIVE BIT_ULL(56)
1264 #define PM_FILE BIT_ULL(61)
1265 #define PM_SWAP BIT_ULL(62)
1266 #define PM_PRESENT BIT_ULL(63)
1268 #define PM_END_OF_BUFFER 1
1270 static inline pagemap_entry_t
make_pme(u64 frame
, u64 flags
)
1272 return (pagemap_entry_t
) { .pme
= (frame
& PM_PFRAME_MASK
) | flags
};
1275 static int add_to_pagemap(unsigned long addr
, pagemap_entry_t
*pme
,
1276 struct pagemapread
*pm
)
1278 pm
->buffer
[pm
->pos
++] = *pme
;
1279 if (pm
->pos
>= pm
->len
)
1280 return PM_END_OF_BUFFER
;
1284 static int pagemap_pte_hole(unsigned long start
, unsigned long end
,
1285 __always_unused
int depth
, struct mm_walk
*walk
)
1287 struct pagemapread
*pm
= walk
->private;
1288 unsigned long addr
= start
;
1291 while (addr
< end
) {
1292 struct vm_area_struct
*vma
= find_vma(walk
->mm
, addr
);
1293 pagemap_entry_t pme
= make_pme(0, 0);
1294 /* End of address space hole, which we mark as non-present. */
1295 unsigned long hole_end
;
1298 hole_end
= min(end
, vma
->vm_start
);
1302 for (; addr
< hole_end
; addr
+= PAGE_SIZE
) {
1303 err
= add_to_pagemap(addr
, &pme
, pm
);
1311 /* Addresses in the VMA. */
1312 if (vma
->vm_flags
& VM_SOFTDIRTY
)
1313 pme
= make_pme(0, PM_SOFT_DIRTY
);
1314 for (; addr
< min(end
, vma
->vm_end
); addr
+= PAGE_SIZE
) {
1315 err
= add_to_pagemap(addr
, &pme
, pm
);
1324 static pagemap_entry_t
pte_to_pagemap_entry(struct pagemapread
*pm
,
1325 struct vm_area_struct
*vma
, unsigned long addr
, pte_t pte
)
1327 u64 frame
= 0, flags
= 0;
1328 struct page
*page
= NULL
;
1330 if (pte_present(pte
)) {
1332 frame
= pte_pfn(pte
);
1333 flags
|= PM_PRESENT
;
1334 page
= vm_normal_page(vma
, addr
, pte
);
1335 if (pte_soft_dirty(pte
))
1336 flags
|= PM_SOFT_DIRTY
;
1337 } else if (is_swap_pte(pte
)) {
1339 if (pte_swp_soft_dirty(pte
))
1340 flags
|= PM_SOFT_DIRTY
;
1341 entry
= pte_to_swp_entry(pte
);
1343 frame
= swp_type(entry
) |
1344 (swp_offset(entry
) << MAX_SWAPFILES_SHIFT
);
1346 if (is_migration_entry(entry
))
1347 page
= migration_entry_to_page(entry
);
1349 if (is_device_private_entry(entry
))
1350 page
= device_private_entry_to_page(entry
);
1353 if (page
&& !PageAnon(page
))
1355 if (page
&& page_mapcount(page
) == 1)
1356 flags
|= PM_MMAP_EXCLUSIVE
;
1357 if (vma
->vm_flags
& VM_SOFTDIRTY
)
1358 flags
|= PM_SOFT_DIRTY
;
1360 return make_pme(frame
, flags
);
1363 static int pagemap_pmd_range(pmd_t
*pmdp
, unsigned long addr
, unsigned long end
,
1364 struct mm_walk
*walk
)
1366 struct vm_area_struct
*vma
= walk
->vma
;
1367 struct pagemapread
*pm
= walk
->private;
1369 pte_t
*pte
, *orig_pte
;
1372 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1373 ptl
= pmd_trans_huge_lock(pmdp
, vma
);
1375 u64 flags
= 0, frame
= 0;
1377 struct page
*page
= NULL
;
1379 if (vma
->vm_flags
& VM_SOFTDIRTY
)
1380 flags
|= PM_SOFT_DIRTY
;
1382 if (pmd_present(pmd
)) {
1383 page
= pmd_page(pmd
);
1385 flags
|= PM_PRESENT
;
1386 if (pmd_soft_dirty(pmd
))
1387 flags
|= PM_SOFT_DIRTY
;
1389 frame
= pmd_pfn(pmd
) +
1390 ((addr
& ~PMD_MASK
) >> PAGE_SHIFT
);
1392 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
1393 else if (is_swap_pmd(pmd
)) {
1394 swp_entry_t entry
= pmd_to_swp_entry(pmd
);
1395 unsigned long offset
;
1398 offset
= swp_offset(entry
) +
1399 ((addr
& ~PMD_MASK
) >> PAGE_SHIFT
);
1400 frame
= swp_type(entry
) |
1401 (offset
<< MAX_SWAPFILES_SHIFT
);
1404 if (pmd_swp_soft_dirty(pmd
))
1405 flags
|= PM_SOFT_DIRTY
;
1406 VM_BUG_ON(!is_pmd_migration_entry(pmd
));
1407 page
= migration_entry_to_page(entry
);
1411 if (page
&& page_mapcount(page
) == 1)
1412 flags
|= PM_MMAP_EXCLUSIVE
;
1414 for (; addr
!= end
; addr
+= PAGE_SIZE
) {
1415 pagemap_entry_t pme
= make_pme(frame
, flags
);
1417 err
= add_to_pagemap(addr
, &pme
, pm
);
1421 if (flags
& PM_PRESENT
)
1423 else if (flags
& PM_SWAP
)
1424 frame
+= (1 << MAX_SWAPFILES_SHIFT
);
1431 if (pmd_trans_unstable(pmdp
))
1433 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1436 * We can assume that @vma always points to a valid one and @end never
1437 * goes beyond vma->vm_end.
1439 orig_pte
= pte
= pte_offset_map_lock(walk
->mm
, pmdp
, addr
, &ptl
);
1440 for (; addr
< end
; pte
++, addr
+= PAGE_SIZE
) {
1441 pagemap_entry_t pme
;
1443 pme
= pte_to_pagemap_entry(pm
, vma
, addr
, *pte
);
1444 err
= add_to_pagemap(addr
, &pme
, pm
);
1448 pte_unmap_unlock(orig_pte
, ptl
);
1455 #ifdef CONFIG_HUGETLB_PAGE
1456 /* This function walks within one hugetlb entry in the single call */
1457 static int pagemap_hugetlb_range(pte_t
*ptep
, unsigned long hmask
,
1458 unsigned long addr
, unsigned long end
,
1459 struct mm_walk
*walk
)
1461 struct pagemapread
*pm
= walk
->private;
1462 struct vm_area_struct
*vma
= walk
->vma
;
1463 u64 flags
= 0, frame
= 0;
1467 if (vma
->vm_flags
& VM_SOFTDIRTY
)
1468 flags
|= PM_SOFT_DIRTY
;
1470 pte
= huge_ptep_get(ptep
);
1471 if (pte_present(pte
)) {
1472 struct page
*page
= pte_page(pte
);
1474 if (!PageAnon(page
))
1477 if (page_mapcount(page
) == 1)
1478 flags
|= PM_MMAP_EXCLUSIVE
;
1480 flags
|= PM_PRESENT
;
1482 frame
= pte_pfn(pte
) +
1483 ((addr
& ~hmask
) >> PAGE_SHIFT
);
1486 for (; addr
!= end
; addr
+= PAGE_SIZE
) {
1487 pagemap_entry_t pme
= make_pme(frame
, flags
);
1489 err
= add_to_pagemap(addr
, &pme
, pm
);
1492 if (pm
->show_pfn
&& (flags
& PM_PRESENT
))
1501 #define pagemap_hugetlb_range NULL
1502 #endif /* HUGETLB_PAGE */
1504 static const struct mm_walk_ops pagemap_ops
= {
1505 .pmd_entry
= pagemap_pmd_range
,
1506 .pte_hole
= pagemap_pte_hole
,
1507 .hugetlb_entry
= pagemap_hugetlb_range
,
1511 * /proc/pid/pagemap - an array mapping virtual pages to pfns
1513 * For each page in the address space, this file contains one 64-bit entry
1514 * consisting of the following:
1516 * Bits 0-54 page frame number (PFN) if present
1517 * Bits 0-4 swap type if swapped
1518 * Bits 5-54 swap offset if swapped
1519 * Bit 55 pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst)
1520 * Bit 56 page exclusively mapped
1522 * Bit 61 page is file-page or shared-anon
1523 * Bit 62 page swapped
1524 * Bit 63 page present
1526 * If the page is not present but in swap, then the PFN contains an
1527 * encoding of the swap file number and the page's offset into the
1528 * swap. Unmapped pages return a null PFN. This allows determining
1529 * precisely which pages are mapped (or in swap) and comparing mapped
1530 * pages between processes.
1532 * Efficient users of this interface will use /proc/pid/maps to
1533 * determine which areas of memory are actually mapped and llseek to
1534 * skip over unmapped regions.
1536 static ssize_t
pagemap_read(struct file
*file
, char __user
*buf
,
1537 size_t count
, loff_t
*ppos
)
1539 struct mm_struct
*mm
= file
->private_data
;
1540 struct pagemapread pm
;
1542 unsigned long svpfn
;
1543 unsigned long start_vaddr
;
1544 unsigned long end_vaddr
;
1545 int ret
= 0, copied
= 0;
1547 if (!mm
|| !mmget_not_zero(mm
))
1551 /* file position must be aligned */
1552 if ((*ppos
% PM_ENTRY_BYTES
) || (count
% PM_ENTRY_BYTES
))
1559 /* do not disclose physical addresses: attack vector */
1560 pm
.show_pfn
= file_ns_capable(file
, &init_user_ns
, CAP_SYS_ADMIN
);
1562 pm
.len
= (PAGEMAP_WALK_SIZE
>> PAGE_SHIFT
);
1563 pm
.buffer
= kmalloc_array(pm
.len
, PM_ENTRY_BYTES
, GFP_KERNEL
);
1569 svpfn
= src
/ PM_ENTRY_BYTES
;
1570 start_vaddr
= svpfn
<< PAGE_SHIFT
;
1571 end_vaddr
= mm
->task_size
;
1573 /* watch out for wraparound */
1574 if (svpfn
> mm
->task_size
>> PAGE_SHIFT
)
1575 start_vaddr
= end_vaddr
;
1578 * The odds are that this will stop walking way
1579 * before end_vaddr, because the length of the
1580 * user buffer is tracked in "pm", and the walk
1581 * will stop when we hit the end of the buffer.
1584 while (count
&& (start_vaddr
< end_vaddr
)) {
1589 end
= (start_vaddr
+ PAGEMAP_WALK_SIZE
) & PAGEMAP_WALK_MASK
;
1591 if (end
< start_vaddr
|| end
> end_vaddr
)
1593 ret
= down_read_killable(&mm
->mmap_sem
);
1596 ret
= walk_page_range(mm
, start_vaddr
, end
, &pagemap_ops
, &pm
);
1597 up_read(&mm
->mmap_sem
);
1600 len
= min(count
, PM_ENTRY_BYTES
* pm
.pos
);
1601 if (copy_to_user(buf
, pm
.buffer
, len
)) {
1610 if (!ret
|| ret
== PM_END_OF_BUFFER
)
1621 static int pagemap_open(struct inode
*inode
, struct file
*file
)
1623 struct mm_struct
*mm
;
1625 mm
= proc_mem_open(inode
, PTRACE_MODE_READ
);
1628 file
->private_data
= mm
;
1632 static int pagemap_release(struct inode
*inode
, struct file
*file
)
1634 struct mm_struct
*mm
= file
->private_data
;
1641 const struct file_operations proc_pagemap_operations
= {
1642 .llseek
= mem_lseek
, /* borrow this */
1643 .read
= pagemap_read
,
1644 .open
= pagemap_open
,
1645 .release
= pagemap_release
,
1647 #endif /* CONFIG_PROC_PAGE_MONITOR */
1652 unsigned long pages
;
1654 unsigned long active
;
1655 unsigned long writeback
;
1656 unsigned long mapcount_max
;
1657 unsigned long dirty
;
1658 unsigned long swapcache
;
1659 unsigned long node
[MAX_NUMNODES
];
1662 struct numa_maps_private
{
1663 struct proc_maps_private proc_maps
;
1664 struct numa_maps md
;
1667 static void gather_stats(struct page
*page
, struct numa_maps
*md
, int pte_dirty
,
1668 unsigned long nr_pages
)
1670 int count
= page_mapcount(page
);
1672 md
->pages
+= nr_pages
;
1673 if (pte_dirty
|| PageDirty(page
))
1674 md
->dirty
+= nr_pages
;
1676 if (PageSwapCache(page
))
1677 md
->swapcache
+= nr_pages
;
1679 if (PageActive(page
) || PageUnevictable(page
))
1680 md
->active
+= nr_pages
;
1682 if (PageWriteback(page
))
1683 md
->writeback
+= nr_pages
;
1686 md
->anon
+= nr_pages
;
1688 if (count
> md
->mapcount_max
)
1689 md
->mapcount_max
= count
;
1691 md
->node
[page_to_nid(page
)] += nr_pages
;
1694 static struct page
*can_gather_numa_stats(pte_t pte
, struct vm_area_struct
*vma
,
1700 if (!pte_present(pte
))
1703 page
= vm_normal_page(vma
, addr
, pte
);
1707 if (PageReserved(page
))
1710 nid
= page_to_nid(page
);
1711 if (!node_isset(nid
, node_states
[N_MEMORY
]))
1717 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1718 static struct page
*can_gather_numa_stats_pmd(pmd_t pmd
,
1719 struct vm_area_struct
*vma
,
1725 if (!pmd_present(pmd
))
1728 page
= vm_normal_page_pmd(vma
, addr
, pmd
);
1732 if (PageReserved(page
))
1735 nid
= page_to_nid(page
);
1736 if (!node_isset(nid
, node_states
[N_MEMORY
]))
1743 static int gather_pte_stats(pmd_t
*pmd
, unsigned long addr
,
1744 unsigned long end
, struct mm_walk
*walk
)
1746 struct numa_maps
*md
= walk
->private;
1747 struct vm_area_struct
*vma
= walk
->vma
;
1752 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1753 ptl
= pmd_trans_huge_lock(pmd
, vma
);
1757 page
= can_gather_numa_stats_pmd(*pmd
, vma
, addr
);
1759 gather_stats(page
, md
, pmd_dirty(*pmd
),
1760 HPAGE_PMD_SIZE
/PAGE_SIZE
);
1765 if (pmd_trans_unstable(pmd
))
1768 orig_pte
= pte
= pte_offset_map_lock(walk
->mm
, pmd
, addr
, &ptl
);
1770 struct page
*page
= can_gather_numa_stats(*pte
, vma
, addr
);
1773 gather_stats(page
, md
, pte_dirty(*pte
), 1);
1775 } while (pte
++, addr
+= PAGE_SIZE
, addr
!= end
);
1776 pte_unmap_unlock(orig_pte
, ptl
);
1780 #ifdef CONFIG_HUGETLB_PAGE
1781 static int gather_hugetlb_stats(pte_t
*pte
, unsigned long hmask
,
1782 unsigned long addr
, unsigned long end
, struct mm_walk
*walk
)
1784 pte_t huge_pte
= huge_ptep_get(pte
);
1785 struct numa_maps
*md
;
1788 if (!pte_present(huge_pte
))
1791 page
= pte_page(huge_pte
);
1796 gather_stats(page
, md
, pte_dirty(huge_pte
), 1);
1801 static int gather_hugetlb_stats(pte_t
*pte
, unsigned long hmask
,
1802 unsigned long addr
, unsigned long end
, struct mm_walk
*walk
)
1808 static const struct mm_walk_ops show_numa_ops
= {
1809 .hugetlb_entry
= gather_hugetlb_stats
,
1810 .pmd_entry
= gather_pte_stats
,
1814 * Display pages allocated per node and memory policy via /proc.
1816 static int show_numa_map(struct seq_file
*m
, void *v
)
1818 struct numa_maps_private
*numa_priv
= m
->private;
1819 struct proc_maps_private
*proc_priv
= &numa_priv
->proc_maps
;
1820 struct vm_area_struct
*vma
= v
;
1821 struct numa_maps
*md
= &numa_priv
->md
;
1822 struct file
*file
= vma
->vm_file
;
1823 struct mm_struct
*mm
= vma
->vm_mm
;
1824 struct mempolicy
*pol
;
1831 /* Ensure we start with an empty set of numa_maps statistics. */
1832 memset(md
, 0, sizeof(*md
));
1834 pol
= __get_vma_policy(vma
, vma
->vm_start
);
1836 mpol_to_str(buffer
, sizeof(buffer
), pol
);
1839 mpol_to_str(buffer
, sizeof(buffer
), proc_priv
->task_mempolicy
);
1842 seq_printf(m
, "%08lx %s", vma
->vm_start
, buffer
);
1845 seq_puts(m
, " file=");
1846 seq_file_path(m
, file
, "\n\t= ");
1847 } else if (vma
->vm_start
<= mm
->brk
&& vma
->vm_end
>= mm
->start_brk
) {
1848 seq_puts(m
, " heap");
1849 } else if (is_stack(vma
)) {
1850 seq_puts(m
, " stack");
1853 if (is_vm_hugetlb_page(vma
))
1854 seq_puts(m
, " huge");
1856 /* mmap_sem is held by m_start */
1857 walk_page_vma(vma
, &show_numa_ops
, md
);
1863 seq_printf(m
, " anon=%lu", md
->anon
);
1866 seq_printf(m
, " dirty=%lu", md
->dirty
);
1868 if (md
->pages
!= md
->anon
&& md
->pages
!= md
->dirty
)
1869 seq_printf(m
, " mapped=%lu", md
->pages
);
1871 if (md
->mapcount_max
> 1)
1872 seq_printf(m
, " mapmax=%lu", md
->mapcount_max
);
1875 seq_printf(m
, " swapcache=%lu", md
->swapcache
);
1877 if (md
->active
< md
->pages
&& !is_vm_hugetlb_page(vma
))
1878 seq_printf(m
, " active=%lu", md
->active
);
1881 seq_printf(m
, " writeback=%lu", md
->writeback
);
1883 for_each_node_state(nid
, N_MEMORY
)
1885 seq_printf(m
, " N%d=%lu", nid
, md
->node
[nid
]);
1887 seq_printf(m
, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma
) >> 10);
1890 m_cache_vma(m
, vma
);
1894 static const struct seq_operations proc_pid_numa_maps_op
= {
1898 .show
= show_numa_map
,
1901 static int pid_numa_maps_open(struct inode
*inode
, struct file
*file
)
1903 return proc_maps_open(inode
, file
, &proc_pid_numa_maps_op
,
1904 sizeof(struct numa_maps_private
));
1907 const struct file_operations proc_pid_numa_maps_operations
= {
1908 .open
= pid_numa_maps_open
,
1910 .llseek
= seq_lseek
,
1911 .release
= proc_map_release
,
1914 #endif /* CONFIG_NUMA */