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1// SPDX-License-Identifier: GPL-2.0
2#include <linux/pagewalk.h>
3#include <linux/mm_inline.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>
22
23#include <asm/elf.h>
24#include <asm/tlb.h>
25#include <asm/tlbflush.h>
26#include "internal.h"
27
28#define SEQ_PUT_DEC(str, val) \
29 seq_put_decimal_ull_width(m, str, (val) << (PAGE_SHIFT-10), 8)
30void task_mem(struct seq_file *m, struct mm_struct *mm)
31{
32 unsigned long text, lib, swap, anon, file, shmem;
33 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
34
35 anon = get_mm_counter(mm, MM_ANONPAGES);
36 file = get_mm_counter(mm, MM_FILEPAGES);
37 shmem = get_mm_counter(mm, MM_SHMEMPAGES);
38
39 /*
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.
45 */
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;
52
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;
57
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);
77 seq_puts(m, " kB\n");
78 hugetlb_report_usage(m, mm);
79}
80#undef SEQ_PUT_DEC
81
82unsigned long task_vsize(struct mm_struct *mm)
83{
84 return PAGE_SIZE * mm->total_vm;
85}
86
87unsigned long task_statm(struct mm_struct *mm,
88 unsigned long *shared, unsigned long *text,
89 unsigned long *data, unsigned long *resident)
90{
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))
94 >> PAGE_SHIFT;
95 *data = mm->data_vm + mm->stack_vm;
96 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
97 return mm->total_vm;
98}
99
100#ifdef CONFIG_NUMA
101/*
102 * Save get_task_policy() for show_numa_map().
103 */
104static void hold_task_mempolicy(struct proc_maps_private *priv)
105{
106 struct task_struct *task = priv->task;
107
108 task_lock(task);
109 priv->task_mempolicy = get_task_policy(task);
110 mpol_get(priv->task_mempolicy);
111 task_unlock(task);
112}
113static void release_task_mempolicy(struct proc_maps_private *priv)
114{
115 mpol_put(priv->task_mempolicy);
116}
117#else
118static void hold_task_mempolicy(struct proc_maps_private *priv)
119{
120}
121static void release_task_mempolicy(struct proc_maps_private *priv)
122{
123}
124#endif
125
126static struct vm_area_struct *proc_get_vma(struct proc_maps_private *priv,
127 loff_t *ppos)
128{
129 struct vm_area_struct *vma = vma_next(&priv->iter);
130
131 if (vma) {
132 *ppos = vma->vm_start;
133 } else {
134 *ppos = -2UL;
135 vma = get_gate_vma(priv->mm);
136 }
137
138 return vma;
139}
140
141static void *m_start(struct seq_file *m, loff_t *ppos)
142{
143 struct proc_maps_private *priv = m->private;
144 unsigned long last_addr = *ppos;
145 struct mm_struct *mm;
146
147 /* See m_next(). Zero at the start or after lseek. */
148 if (last_addr == -1UL)
149 return NULL;
150
151 priv->task = get_proc_task(priv->inode);
152 if (!priv->task)
153 return ERR_PTR(-ESRCH);
154
155 mm = priv->mm;
156 if (!mm || !mmget_not_zero(mm)) {
157 put_task_struct(priv->task);
158 priv->task = NULL;
159 return NULL;
160 }
161
162 if (mmap_read_lock_killable(mm)) {
163 mmput(mm);
164 put_task_struct(priv->task);
165 priv->task = NULL;
166 return ERR_PTR(-EINTR);
167 }
168
169 vma_iter_init(&priv->iter, mm, last_addr);
170 hold_task_mempolicy(priv);
171 if (last_addr == -2UL)
172 return get_gate_vma(mm);
173
174 return proc_get_vma(priv, ppos);
175}
176
177static void *m_next(struct seq_file *m, void *v, loff_t *ppos)
178{
179 if (*ppos == -2UL) {
180 *ppos = -1UL;
181 return NULL;
182 }
183 return proc_get_vma(m->private, ppos);
184}
185
186static void m_stop(struct seq_file *m, void *v)
187{
188 struct proc_maps_private *priv = m->private;
189 struct mm_struct *mm = priv->mm;
190
191 if (!priv->task)
192 return;
193
194 release_task_mempolicy(priv);
195 mmap_read_unlock(mm);
196 mmput(mm);
197 put_task_struct(priv->task);
198 priv->task = NULL;
199}
200
201static int proc_maps_open(struct inode *inode, struct file *file,
202 const struct seq_operations *ops, int psize)
203{
204 struct proc_maps_private *priv = __seq_open_private(file, ops, psize);
205
206 if (!priv)
207 return -ENOMEM;
208
209 priv->inode = inode;
210 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
211 if (IS_ERR(priv->mm)) {
212 int err = PTR_ERR(priv->mm);
213
214 seq_release_private(inode, file);
215 return err;
216 }
217
218 return 0;
219}
220
221static int proc_map_release(struct inode *inode, struct file *file)
222{
223 struct seq_file *seq = file->private_data;
224 struct proc_maps_private *priv = seq->private;
225
226 if (priv->mm)
227 mmdrop(priv->mm);
228
229 return seq_release_private(inode, file);
230}
231
232static int do_maps_open(struct inode *inode, struct file *file,
233 const struct seq_operations *ops)
234{
235 return proc_maps_open(inode, file, ops,
236 sizeof(struct proc_maps_private));
237}
238
239/*
240 * Indicate if the VMA is a stack for the given task; for
241 * /proc/PID/maps that is the stack of the main task.
242 */
243static int is_stack(struct vm_area_struct *vma)
244{
245 /*
246 * We make no effort to guess what a given thread considers to be
247 * its "stack". It's not even well-defined for programs written
248 * languages like Go.
249 */
250 return vma->vm_start <= vma->vm_mm->start_stack &&
251 vma->vm_end >= vma->vm_mm->start_stack;
252}
253
254static void show_vma_header_prefix(struct seq_file *m,
255 unsigned long start, unsigned long end,
256 vm_flags_t flags, unsigned long long pgoff,
257 dev_t dev, unsigned long ino)
258{
259 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
260 seq_put_hex_ll(m, NULL, start, 8);
261 seq_put_hex_ll(m, "-", end, 8);
262 seq_putc(m, ' ');
263 seq_putc(m, flags & VM_READ ? 'r' : '-');
264 seq_putc(m, flags & VM_WRITE ? 'w' : '-');
265 seq_putc(m, flags & VM_EXEC ? 'x' : '-');
266 seq_putc(m, flags & VM_MAYSHARE ? 's' : 'p');
267 seq_put_hex_ll(m, " ", pgoff, 8);
268 seq_put_hex_ll(m, " ", MAJOR(dev), 2);
269 seq_put_hex_ll(m, ":", MINOR(dev), 2);
270 seq_put_decimal_ull(m, " ", ino);
271 seq_putc(m, ' ');
272}
273
274static void
275show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
276{
277 struct anon_vma_name *anon_name = NULL;
278 struct mm_struct *mm = vma->vm_mm;
279 struct file *file = vma->vm_file;
280 vm_flags_t flags = vma->vm_flags;
281 unsigned long ino = 0;
282 unsigned long long pgoff = 0;
283 unsigned long start, end;
284 dev_t dev = 0;
285 const char *name = NULL;
286
287 if (file) {
288 struct inode *inode = file_inode(vma->vm_file);
289 dev = inode->i_sb->s_dev;
290 ino = inode->i_ino;
291 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
292 }
293
294 start = vma->vm_start;
295 end = vma->vm_end;
296 show_vma_header_prefix(m, start, end, flags, pgoff, dev, ino);
297 if (mm)
298 anon_name = anon_vma_name(vma);
299
300 /*
301 * Print the dentry name for named mappings, and a
302 * special [heap] marker for the heap:
303 */
304 if (file) {
305 seq_pad(m, ' ');
306 /*
307 * If user named this anon shared memory via
308 * prctl(PR_SET_VMA ..., use the provided name.
309 */
310 if (anon_name)
311 seq_printf(m, "[anon_shmem:%s]", anon_name->name);
312 else
313 seq_file_path(m, file, "\n");
314 goto done;
315 }
316
317 if (vma->vm_ops && vma->vm_ops->name) {
318 name = vma->vm_ops->name(vma);
319 if (name)
320 goto done;
321 }
322
323 name = arch_vma_name(vma);
324 if (!name) {
325 if (!mm) {
326 name = "[vdso]";
327 goto done;
328 }
329
330 if (vma->vm_start <= mm->brk &&
331 vma->vm_end >= mm->start_brk) {
332 name = "[heap]";
333 goto done;
334 }
335
336 if (is_stack(vma)) {
337 name = "[stack]";
338 goto done;
339 }
340
341 if (anon_name) {
342 seq_pad(m, ' ');
343 seq_printf(m, "[anon:%s]", anon_name->name);
344 }
345 }
346
347done:
348 if (name) {
349 seq_pad(m, ' ');
350 seq_puts(m, name);
351 }
352 seq_putc(m, '\n');
353}
354
355static int show_map(struct seq_file *m, void *v)
356{
357 show_map_vma(m, v);
358 return 0;
359}
360
361static const struct seq_operations proc_pid_maps_op = {
362 .start = m_start,
363 .next = m_next,
364 .stop = m_stop,
365 .show = show_map
366};
367
368static int pid_maps_open(struct inode *inode, struct file *file)
369{
370 return do_maps_open(inode, file, &proc_pid_maps_op);
371}
372
373const struct file_operations proc_pid_maps_operations = {
374 .open = pid_maps_open,
375 .read = seq_read,
376 .llseek = seq_lseek,
377 .release = proc_map_release,
378};
379
380/*
381 * Proportional Set Size(PSS): my share of RSS.
382 *
383 * PSS of a process is the count of pages it has in memory, where each
384 * page is divided by the number of processes sharing it. So if a
385 * process has 1000 pages all to itself, and 1000 shared with one other
386 * process, its PSS will be 1500.
387 *
388 * To keep (accumulated) division errors low, we adopt a 64bit
389 * fixed-point pss counter to minimize division errors. So (pss >>
390 * PSS_SHIFT) would be the real byte count.
391 *
392 * A shift of 12 before division means (assuming 4K page size):
393 * - 1M 3-user-pages add up to 8KB errors;
394 * - supports mapcount up to 2^24, or 16M;
395 * - supports PSS up to 2^52 bytes, or 4PB.
396 */
397#define PSS_SHIFT 12
398
399#ifdef CONFIG_PROC_PAGE_MONITOR
400struct mem_size_stats {
401 unsigned long resident;
402 unsigned long shared_clean;
403 unsigned long shared_dirty;
404 unsigned long private_clean;
405 unsigned long private_dirty;
406 unsigned long referenced;
407 unsigned long anonymous;
408 unsigned long lazyfree;
409 unsigned long anonymous_thp;
410 unsigned long shmem_thp;
411 unsigned long file_thp;
412 unsigned long swap;
413 unsigned long shared_hugetlb;
414 unsigned long private_hugetlb;
415 u64 pss;
416 u64 pss_anon;
417 u64 pss_file;
418 u64 pss_shmem;
419 u64 pss_dirty;
420 u64 pss_locked;
421 u64 swap_pss;
422};
423
424static void smaps_page_accumulate(struct mem_size_stats *mss,
425 struct page *page, unsigned long size, unsigned long pss,
426 bool dirty, bool locked, bool private)
427{
428 mss->pss += pss;
429
430 if (PageAnon(page))
431 mss->pss_anon += pss;
432 else if (PageSwapBacked(page))
433 mss->pss_shmem += pss;
434 else
435 mss->pss_file += pss;
436
437 if (locked)
438 mss->pss_locked += pss;
439
440 if (dirty || PageDirty(page)) {
441 mss->pss_dirty += pss;
442 if (private)
443 mss->private_dirty += size;
444 else
445 mss->shared_dirty += size;
446 } else {
447 if (private)
448 mss->private_clean += size;
449 else
450 mss->shared_clean += size;
451 }
452}
453
454static void smaps_account(struct mem_size_stats *mss, struct page *page,
455 bool compound, bool young, bool dirty, bool locked,
456 bool migration)
457{
458 int i, nr = compound ? compound_nr(page) : 1;
459 unsigned long size = nr * PAGE_SIZE;
460
461 /*
462 * First accumulate quantities that depend only on |size| and the type
463 * of the compound page.
464 */
465 if (PageAnon(page)) {
466 mss->anonymous += size;
467 if (!PageSwapBacked(page) && !dirty && !PageDirty(page))
468 mss->lazyfree += size;
469 }
470
471 mss->resident += size;
472 /* Accumulate the size in pages that have been accessed. */
473 if (young || page_is_young(page) || PageReferenced(page))
474 mss->referenced += size;
475
476 /*
477 * Then accumulate quantities that may depend on sharing, or that may
478 * differ page-by-page.
479 *
480 * page_count(page) == 1 guarantees the page is mapped exactly once.
481 * If any subpage of the compound page mapped with PTE it would elevate
482 * page_count().
483 *
484 * The page_mapcount() is called to get a snapshot of the mapcount.
485 * Without holding the page lock this snapshot can be slightly wrong as
486 * we cannot always read the mapcount atomically. It is not safe to
487 * call page_mapcount() even with PTL held if the page is not mapped,
488 * especially for migration entries. Treat regular migration entries
489 * as mapcount == 1.
490 */
491 if ((page_count(page) == 1) || migration) {
492 smaps_page_accumulate(mss, page, size, size << PSS_SHIFT, dirty,
493 locked, true);
494 return;
495 }
496 for (i = 0; i < nr; i++, page++) {
497 int mapcount = page_mapcount(page);
498 unsigned long pss = PAGE_SIZE << PSS_SHIFT;
499 if (mapcount >= 2)
500 pss /= mapcount;
501 smaps_page_accumulate(mss, page, PAGE_SIZE, pss, dirty, locked,
502 mapcount < 2);
503 }
504}
505
506#ifdef CONFIG_SHMEM
507static int smaps_pte_hole(unsigned long addr, unsigned long end,
508 __always_unused int depth, struct mm_walk *walk)
509{
510 struct mem_size_stats *mss = walk->private;
511 struct vm_area_struct *vma = walk->vma;
512
513 mss->swap += shmem_partial_swap_usage(walk->vma->vm_file->f_mapping,
514 linear_page_index(vma, addr),
515 linear_page_index(vma, end));
516
517 return 0;
518}
519#else
520#define smaps_pte_hole NULL
521#endif /* CONFIG_SHMEM */
522
523static void smaps_pte_hole_lookup(unsigned long addr, struct mm_walk *walk)
524{
525#ifdef CONFIG_SHMEM
526 if (walk->ops->pte_hole) {
527 /* depth is not used */
528 smaps_pte_hole(addr, addr + PAGE_SIZE, 0, walk);
529 }
530#endif
531}
532
533static void smaps_pte_entry(pte_t *pte, unsigned long addr,
534 struct mm_walk *walk)
535{
536 struct mem_size_stats *mss = walk->private;
537 struct vm_area_struct *vma = walk->vma;
538 bool locked = !!(vma->vm_flags & VM_LOCKED);
539 struct page *page = NULL;
540 bool migration = false, young = false, dirty = false;
541
542 if (pte_present(*pte)) {
543 page = vm_normal_page(vma, addr, *pte);
544 young = pte_young(*pte);
545 dirty = pte_dirty(*pte);
546 } else if (is_swap_pte(*pte)) {
547 swp_entry_t swpent = pte_to_swp_entry(*pte);
548
549 if (!non_swap_entry(swpent)) {
550 int mapcount;
551
552 mss->swap += PAGE_SIZE;
553 mapcount = swp_swapcount(swpent);
554 if (mapcount >= 2) {
555 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT;
556
557 do_div(pss_delta, mapcount);
558 mss->swap_pss += pss_delta;
559 } else {
560 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT;
561 }
562 } else if (is_pfn_swap_entry(swpent)) {
563 if (is_migration_entry(swpent))
564 migration = true;
565 page = pfn_swap_entry_to_page(swpent);
566 }
567 } else {
568 smaps_pte_hole_lookup(addr, walk);
569 return;
570 }
571
572 if (!page)
573 return;
574
575 smaps_account(mss, page, false, young, dirty, locked, migration);
576}
577
578#ifdef CONFIG_TRANSPARENT_HUGEPAGE
579static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
580 struct mm_walk *walk)
581{
582 struct mem_size_stats *mss = walk->private;
583 struct vm_area_struct *vma = walk->vma;
584 bool locked = !!(vma->vm_flags & VM_LOCKED);
585 struct page *page = NULL;
586 bool migration = false;
587
588 if (pmd_present(*pmd)) {
589 /* FOLL_DUMP will return -EFAULT on huge zero page */
590 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
591 } else if (unlikely(thp_migration_supported() && is_swap_pmd(*pmd))) {
592 swp_entry_t entry = pmd_to_swp_entry(*pmd);
593
594 if (is_migration_entry(entry)) {
595 migration = true;
596 page = pfn_swap_entry_to_page(entry);
597 }
598 }
599 if (IS_ERR_OR_NULL(page))
600 return;
601 if (PageAnon(page))
602 mss->anonymous_thp += HPAGE_PMD_SIZE;
603 else if (PageSwapBacked(page))
604 mss->shmem_thp += HPAGE_PMD_SIZE;
605 else if (is_zone_device_page(page))
606 /* pass */;
607 else
608 mss->file_thp += HPAGE_PMD_SIZE;
609
610 smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd),
611 locked, migration);
612}
613#else
614static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
615 struct mm_walk *walk)
616{
617}
618#endif
619
620static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
621 struct mm_walk *walk)
622{
623 struct vm_area_struct *vma = walk->vma;
624 pte_t *pte;
625 spinlock_t *ptl;
626
627 ptl = pmd_trans_huge_lock(pmd, vma);
628 if (ptl) {
629 smaps_pmd_entry(pmd, addr, walk);
630 spin_unlock(ptl);
631 goto out;
632 }
633
634 if (pmd_trans_unstable(pmd))
635 goto out;
636 /*
637 * The mmap_lock held all the way back in m_start() is what
638 * keeps khugepaged out of here and from collapsing things
639 * in here.
640 */
641 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
642 for (; addr != end; pte++, addr += PAGE_SIZE)
643 smaps_pte_entry(pte, addr, walk);
644 pte_unmap_unlock(pte - 1, ptl);
645out:
646 cond_resched();
647 return 0;
648}
649
650static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
651{
652 /*
653 * Don't forget to update Documentation/ on changes.
654 */
655 static const char mnemonics[BITS_PER_LONG][2] = {
656 /*
657 * In case if we meet a flag we don't know about.
658 */
659 [0 ... (BITS_PER_LONG-1)] = "??",
660
661 [ilog2(VM_READ)] = "rd",
662 [ilog2(VM_WRITE)] = "wr",
663 [ilog2(VM_EXEC)] = "ex",
664 [ilog2(VM_SHARED)] = "sh",
665 [ilog2(VM_MAYREAD)] = "mr",
666 [ilog2(VM_MAYWRITE)] = "mw",
667 [ilog2(VM_MAYEXEC)] = "me",
668 [ilog2(VM_MAYSHARE)] = "ms",
669 [ilog2(VM_GROWSDOWN)] = "gd",
670 [ilog2(VM_PFNMAP)] = "pf",
671 [ilog2(VM_LOCKED)] = "lo",
672 [ilog2(VM_IO)] = "io",
673 [ilog2(VM_SEQ_READ)] = "sr",
674 [ilog2(VM_RAND_READ)] = "rr",
675 [ilog2(VM_DONTCOPY)] = "dc",
676 [ilog2(VM_DONTEXPAND)] = "de",
677 [ilog2(VM_LOCKONFAULT)] = "lf",
678 [ilog2(VM_ACCOUNT)] = "ac",
679 [ilog2(VM_NORESERVE)] = "nr",
680 [ilog2(VM_HUGETLB)] = "ht",
681 [ilog2(VM_SYNC)] = "sf",
682 [ilog2(VM_ARCH_1)] = "ar",
683 [ilog2(VM_WIPEONFORK)] = "wf",
684 [ilog2(VM_DONTDUMP)] = "dd",
685#ifdef CONFIG_ARM64_BTI
686 [ilog2(VM_ARM64_BTI)] = "bt",
687#endif
688#ifdef CONFIG_MEM_SOFT_DIRTY
689 [ilog2(VM_SOFTDIRTY)] = "sd",
690#endif
691 [ilog2(VM_MIXEDMAP)] = "mm",
692 [ilog2(VM_HUGEPAGE)] = "hg",
693 [ilog2(VM_NOHUGEPAGE)] = "nh",
694 [ilog2(VM_MERGEABLE)] = "mg",
695 [ilog2(VM_UFFD_MISSING)]= "um",
696 [ilog2(VM_UFFD_WP)] = "uw",
697#ifdef CONFIG_ARM64_MTE
698 [ilog2(VM_MTE)] = "mt",
699 [ilog2(VM_MTE_ALLOWED)] = "",
700#endif
701#ifdef CONFIG_ARCH_HAS_PKEYS
702 /* These come out via ProtectionKey: */
703 [ilog2(VM_PKEY_BIT0)] = "",
704 [ilog2(VM_PKEY_BIT1)] = "",
705 [ilog2(VM_PKEY_BIT2)] = "",
706 [ilog2(VM_PKEY_BIT3)] = "",
707#if VM_PKEY_BIT4
708 [ilog2(VM_PKEY_BIT4)] = "",
709#endif
710#endif /* CONFIG_ARCH_HAS_PKEYS */
711#ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR
712 [ilog2(VM_UFFD_MINOR)] = "ui",
713#endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */
714 };
715 size_t i;
716
717 seq_puts(m, "VmFlags: ");
718 for (i = 0; i < BITS_PER_LONG; i++) {
719 if (!mnemonics[i][0])
720 continue;
721 if (vma->vm_flags & (1UL << i)) {
722 seq_putc(m, mnemonics[i][0]);
723 seq_putc(m, mnemonics[i][1]);
724 seq_putc(m, ' ');
725 }
726 }
727 seq_putc(m, '\n');
728}
729
730#ifdef CONFIG_HUGETLB_PAGE
731static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,
732 unsigned long addr, unsigned long end,
733 struct mm_walk *walk)
734{
735 struct mem_size_stats *mss = walk->private;
736 struct vm_area_struct *vma = walk->vma;
737 struct page *page = NULL;
738
739 if (pte_present(*pte)) {
740 page = vm_normal_page(vma, addr, *pte);
741 } else if (is_swap_pte(*pte)) {
742 swp_entry_t swpent = pte_to_swp_entry(*pte);
743
744 if (is_pfn_swap_entry(swpent))
745 page = pfn_swap_entry_to_page(swpent);
746 }
747 if (page) {
748 if (page_mapcount(page) >= 2 || hugetlb_pmd_shared(pte))
749 mss->shared_hugetlb += huge_page_size(hstate_vma(vma));
750 else
751 mss->private_hugetlb += huge_page_size(hstate_vma(vma));
752 }
753 return 0;
754}
755#else
756#define smaps_hugetlb_range NULL
757#endif /* HUGETLB_PAGE */
758
759static const struct mm_walk_ops smaps_walk_ops = {
760 .pmd_entry = smaps_pte_range,
761 .hugetlb_entry = smaps_hugetlb_range,
762};
763
764static const struct mm_walk_ops smaps_shmem_walk_ops = {
765 .pmd_entry = smaps_pte_range,
766 .hugetlb_entry = smaps_hugetlb_range,
767 .pte_hole = smaps_pte_hole,
768};
769
770/*
771 * Gather mem stats from @vma with the indicated beginning
772 * address @start, and keep them in @mss.
773 *
774 * Use vm_start of @vma as the beginning address if @start is 0.
775 */
776static void smap_gather_stats(struct vm_area_struct *vma,
777 struct mem_size_stats *mss, unsigned long start)
778{
779 const struct mm_walk_ops *ops = &smaps_walk_ops;
780
781 /* Invalid start */
782 if (start >= vma->vm_end)
783 return;
784
785#ifdef CONFIG_SHMEM
786 if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) {
787 /*
788 * For shared or readonly shmem mappings we know that all
789 * swapped out pages belong to the shmem object, and we can
790 * obtain the swap value much more efficiently. For private
791 * writable mappings, we might have COW pages that are
792 * not affected by the parent swapped out pages of the shmem
793 * object, so we have to distinguish them during the page walk.
794 * Unless we know that the shmem object (or the part mapped by
795 * our VMA) has no swapped out pages at all.
796 */
797 unsigned long shmem_swapped = shmem_swap_usage(vma);
798
799 if (!start && (!shmem_swapped || (vma->vm_flags & VM_SHARED) ||
800 !(vma->vm_flags & VM_WRITE))) {
801 mss->swap += shmem_swapped;
802 } else {
803 ops = &smaps_shmem_walk_ops;
804 }
805 }
806#endif
807 /* mmap_lock is held in m_start */
808 if (!start)
809 walk_page_vma(vma, ops, mss);
810 else
811 walk_page_range(vma->vm_mm, start, vma->vm_end, ops, mss);
812}
813
814#define SEQ_PUT_DEC(str, val) \
815 seq_put_decimal_ull_width(m, str, (val) >> 10, 8)
816
817/* Show the contents common for smaps and smaps_rollup */
818static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss,
819 bool rollup_mode)
820{
821 SEQ_PUT_DEC("Rss: ", mss->resident);
822 SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT);
823 SEQ_PUT_DEC(" kB\nPss_Dirty: ", mss->pss_dirty >> PSS_SHIFT);
824 if (rollup_mode) {
825 /*
826 * These are meaningful only for smaps_rollup, otherwise two of
827 * them are zero, and the other one is the same as Pss.
828 */
829 SEQ_PUT_DEC(" kB\nPss_Anon: ",
830 mss->pss_anon >> PSS_SHIFT);
831 SEQ_PUT_DEC(" kB\nPss_File: ",
832 mss->pss_file >> PSS_SHIFT);
833 SEQ_PUT_DEC(" kB\nPss_Shmem: ",
834 mss->pss_shmem >> PSS_SHIFT);
835 }
836 SEQ_PUT_DEC(" kB\nShared_Clean: ", mss->shared_clean);
837 SEQ_PUT_DEC(" kB\nShared_Dirty: ", mss->shared_dirty);
838 SEQ_PUT_DEC(" kB\nPrivate_Clean: ", mss->private_clean);
839 SEQ_PUT_DEC(" kB\nPrivate_Dirty: ", mss->private_dirty);
840 SEQ_PUT_DEC(" kB\nReferenced: ", mss->referenced);
841 SEQ_PUT_DEC(" kB\nAnonymous: ", mss->anonymous);
842 SEQ_PUT_DEC(" kB\nLazyFree: ", mss->lazyfree);
843 SEQ_PUT_DEC(" kB\nAnonHugePages: ", mss->anonymous_thp);
844 SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp);
845 SEQ_PUT_DEC(" kB\nFilePmdMapped: ", mss->file_thp);
846 SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb);
847 seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ",
848 mss->private_hugetlb >> 10, 7);
849 SEQ_PUT_DEC(" kB\nSwap: ", mss->swap);
850 SEQ_PUT_DEC(" kB\nSwapPss: ",
851 mss->swap_pss >> PSS_SHIFT);
852 SEQ_PUT_DEC(" kB\nLocked: ",
853 mss->pss_locked >> PSS_SHIFT);
854 seq_puts(m, " kB\n");
855}
856
857static int show_smap(struct seq_file *m, void *v)
858{
859 struct vm_area_struct *vma = v;
860 struct mem_size_stats mss;
861
862 memset(&mss, 0, sizeof(mss));
863
864 smap_gather_stats(vma, &mss, 0);
865
866 show_map_vma(m, vma);
867
868 SEQ_PUT_DEC("Size: ", vma->vm_end - vma->vm_start);
869 SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma));
870 SEQ_PUT_DEC(" kB\nMMUPageSize: ", vma_mmu_pagesize(vma));
871 seq_puts(m, " kB\n");
872
873 __show_smap(m, &mss, false);
874
875 seq_printf(m, "THPeligible: %d\n",
876 hugepage_vma_check(vma, vma->vm_flags, true, false, true));
877
878 if (arch_pkeys_enabled())
879 seq_printf(m, "ProtectionKey: %8u\n", vma_pkey(vma));
880 show_smap_vma_flags(m, vma);
881
882 return 0;
883}
884
885static int show_smaps_rollup(struct seq_file *m, void *v)
886{
887 struct proc_maps_private *priv = m->private;
888 struct mem_size_stats mss;
889 struct mm_struct *mm = priv->mm;
890 struct vm_area_struct *vma;
891 unsigned long vma_start = 0, last_vma_end = 0;
892 int ret = 0;
893 MA_STATE(mas, &mm->mm_mt, 0, 0);
894
895 priv->task = get_proc_task(priv->inode);
896 if (!priv->task)
897 return -ESRCH;
898
899 if (!mm || !mmget_not_zero(mm)) {
900 ret = -ESRCH;
901 goto out_put_task;
902 }
903
904 memset(&mss, 0, sizeof(mss));
905
906 ret = mmap_read_lock_killable(mm);
907 if (ret)
908 goto out_put_mm;
909
910 hold_task_mempolicy(priv);
911 vma = mas_find(&mas, ULONG_MAX);
912
913 if (unlikely(!vma))
914 goto empty_set;
915
916 vma_start = vma->vm_start;
917 do {
918 smap_gather_stats(vma, &mss, 0);
919 last_vma_end = vma->vm_end;
920
921 /*
922 * Release mmap_lock temporarily if someone wants to
923 * access it for write request.
924 */
925 if (mmap_lock_is_contended(mm)) {
926 mas_pause(&mas);
927 mmap_read_unlock(mm);
928 ret = mmap_read_lock_killable(mm);
929 if (ret) {
930 release_task_mempolicy(priv);
931 goto out_put_mm;
932 }
933
934 /*
935 * After dropping the lock, there are four cases to
936 * consider. See the following example for explanation.
937 *
938 * +------+------+-----------+
939 * | VMA1 | VMA2 | VMA3 |
940 * +------+------+-----------+
941 * | | | |
942 * 4k 8k 16k 400k
943 *
944 * Suppose we drop the lock after reading VMA2 due to
945 * contention, then we get:
946 *
947 * last_vma_end = 16k
948 *
949 * 1) VMA2 is freed, but VMA3 exists:
950 *
951 * find_vma(mm, 16k - 1) will return VMA3.
952 * In this case, just continue from VMA3.
953 *
954 * 2) VMA2 still exists:
955 *
956 * find_vma(mm, 16k - 1) will return VMA2.
957 * Iterate the loop like the original one.
958 *
959 * 3) No more VMAs can be found:
960 *
961 * find_vma(mm, 16k - 1) will return NULL.
962 * No more things to do, just break.
963 *
964 * 4) (last_vma_end - 1) is the middle of a vma (VMA'):
965 *
966 * find_vma(mm, 16k - 1) will return VMA' whose range
967 * contains last_vma_end.
968 * Iterate VMA' from last_vma_end.
969 */
970 vma = mas_find(&mas, ULONG_MAX);
971 /* Case 3 above */
972 if (!vma)
973 break;
974
975 /* Case 1 above */
976 if (vma->vm_start >= last_vma_end)
977 continue;
978
979 /* Case 4 above */
980 if (vma->vm_end > last_vma_end)
981 smap_gather_stats(vma, &mss, last_vma_end);
982 }
983 /* Case 2 above */
984 } while ((vma = mas_find(&mas, ULONG_MAX)) != NULL);
985
986empty_set:
987 show_vma_header_prefix(m, vma_start, last_vma_end, 0, 0, 0, 0);
988 seq_pad(m, ' ');
989 seq_puts(m, "[rollup]\n");
990
991 __show_smap(m, &mss, true);
992
993 release_task_mempolicy(priv);
994 mmap_read_unlock(mm);
995
996out_put_mm:
997 mmput(mm);
998out_put_task:
999 put_task_struct(priv->task);
1000 priv->task = NULL;
1001
1002 return ret;
1003}
1004#undef SEQ_PUT_DEC
1005
1006static const struct seq_operations proc_pid_smaps_op = {
1007 .start = m_start,
1008 .next = m_next,
1009 .stop = m_stop,
1010 .show = show_smap
1011};
1012
1013static int pid_smaps_open(struct inode *inode, struct file *file)
1014{
1015 return do_maps_open(inode, file, &proc_pid_smaps_op);
1016}
1017
1018static int smaps_rollup_open(struct inode *inode, struct file *file)
1019{
1020 int ret;
1021 struct proc_maps_private *priv;
1022
1023 priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT);
1024 if (!priv)
1025 return -ENOMEM;
1026
1027 ret = single_open(file, show_smaps_rollup, priv);
1028 if (ret)
1029 goto out_free;
1030
1031 priv->inode = inode;
1032 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
1033 if (IS_ERR(priv->mm)) {
1034 ret = PTR_ERR(priv->mm);
1035
1036 single_release(inode, file);
1037 goto out_free;
1038 }
1039
1040 return 0;
1041
1042out_free:
1043 kfree(priv);
1044 return ret;
1045}
1046
1047static int smaps_rollup_release(struct inode *inode, struct file *file)
1048{
1049 struct seq_file *seq = file->private_data;
1050 struct proc_maps_private *priv = seq->private;
1051
1052 if (priv->mm)
1053 mmdrop(priv->mm);
1054
1055 kfree(priv);
1056 return single_release(inode, file);
1057}
1058
1059const struct file_operations proc_pid_smaps_operations = {
1060 .open = pid_smaps_open,
1061 .read = seq_read,
1062 .llseek = seq_lseek,
1063 .release = proc_map_release,
1064};
1065
1066const struct file_operations proc_pid_smaps_rollup_operations = {
1067 .open = smaps_rollup_open,
1068 .read = seq_read,
1069 .llseek = seq_lseek,
1070 .release = smaps_rollup_release,
1071};
1072
1073enum clear_refs_types {
1074 CLEAR_REFS_ALL = 1,
1075 CLEAR_REFS_ANON,
1076 CLEAR_REFS_MAPPED,
1077 CLEAR_REFS_SOFT_DIRTY,
1078 CLEAR_REFS_MM_HIWATER_RSS,
1079 CLEAR_REFS_LAST,
1080};
1081
1082struct clear_refs_private {
1083 enum clear_refs_types type;
1084};
1085
1086#ifdef CONFIG_MEM_SOFT_DIRTY
1087
1088static inline bool pte_is_pinned(struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1089{
1090 struct page *page;
1091
1092 if (!pte_write(pte))
1093 return false;
1094 if (!is_cow_mapping(vma->vm_flags))
1095 return false;
1096 if (likely(!test_bit(MMF_HAS_PINNED, &vma->vm_mm->flags)))
1097 return false;
1098 page = vm_normal_page(vma, addr, pte);
1099 if (!page)
1100 return false;
1101 return page_maybe_dma_pinned(page);
1102}
1103
1104static inline void clear_soft_dirty(struct vm_area_struct *vma,
1105 unsigned long addr, pte_t *pte)
1106{
1107 /*
1108 * The soft-dirty tracker uses #PF-s to catch writes
1109 * to pages, so write-protect the pte as well. See the
1110 * Documentation/admin-guide/mm/soft-dirty.rst for full description
1111 * of how soft-dirty works.
1112 */
1113 pte_t ptent = *pte;
1114
1115 if (pte_present(ptent)) {
1116 pte_t old_pte;
1117
1118 if (pte_is_pinned(vma, addr, ptent))
1119 return;
1120 old_pte = ptep_modify_prot_start(vma, addr, pte);
1121 ptent = pte_wrprotect(old_pte);
1122 ptent = pte_clear_soft_dirty(ptent);
1123 ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent);
1124 } else if (is_swap_pte(ptent)) {
1125 ptent = pte_swp_clear_soft_dirty(ptent);
1126 set_pte_at(vma->vm_mm, addr, pte, ptent);
1127 }
1128}
1129#else
1130static inline void clear_soft_dirty(struct vm_area_struct *vma,
1131 unsigned long addr, pte_t *pte)
1132{
1133}
1134#endif
1135
1136#if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
1137static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
1138 unsigned long addr, pmd_t *pmdp)
1139{
1140 pmd_t old, pmd = *pmdp;
1141
1142 if (pmd_present(pmd)) {
1143 /* See comment in change_huge_pmd() */
1144 old = pmdp_invalidate(vma, addr, pmdp);
1145 if (pmd_dirty(old))
1146 pmd = pmd_mkdirty(pmd);
1147 if (pmd_young(old))
1148 pmd = pmd_mkyoung(pmd);
1149
1150 pmd = pmd_wrprotect(pmd);
1151 pmd = pmd_clear_soft_dirty(pmd);
1152
1153 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
1154 } else if (is_migration_entry(pmd_to_swp_entry(pmd))) {
1155 pmd = pmd_swp_clear_soft_dirty(pmd);
1156 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
1157 }
1158}
1159#else
1160static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
1161 unsigned long addr, pmd_t *pmdp)
1162{
1163}
1164#endif
1165
1166static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
1167 unsigned long end, struct mm_walk *walk)
1168{
1169 struct clear_refs_private *cp = walk->private;
1170 struct vm_area_struct *vma = walk->vma;
1171 pte_t *pte, ptent;
1172 spinlock_t *ptl;
1173 struct page *page;
1174
1175 ptl = pmd_trans_huge_lock(pmd, vma);
1176 if (ptl) {
1177 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
1178 clear_soft_dirty_pmd(vma, addr, pmd);
1179 goto out;
1180 }
1181
1182 if (!pmd_present(*pmd))
1183 goto out;
1184
1185 page = pmd_page(*pmd);
1186
1187 /* Clear accessed and referenced bits. */
1188 pmdp_test_and_clear_young(vma, addr, pmd);
1189 test_and_clear_page_young(page);
1190 ClearPageReferenced(page);
1191out:
1192 spin_unlock(ptl);
1193 return 0;
1194 }
1195
1196 if (pmd_trans_unstable(pmd))
1197 return 0;
1198
1199 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
1200 for (; addr != end; pte++, addr += PAGE_SIZE) {
1201 ptent = *pte;
1202
1203 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
1204 clear_soft_dirty(vma, addr, pte);
1205 continue;
1206 }
1207
1208 if (!pte_present(ptent))
1209 continue;
1210
1211 page = vm_normal_page(vma, addr, ptent);
1212 if (!page)
1213 continue;
1214
1215 /* Clear accessed and referenced bits. */
1216 ptep_test_and_clear_young(vma, addr, pte);
1217 test_and_clear_page_young(page);
1218 ClearPageReferenced(page);
1219 }
1220 pte_unmap_unlock(pte - 1, ptl);
1221 cond_resched();
1222 return 0;
1223}
1224
1225static int clear_refs_test_walk(unsigned long start, unsigned long end,
1226 struct mm_walk *walk)
1227{
1228 struct clear_refs_private *cp = walk->private;
1229 struct vm_area_struct *vma = walk->vma;
1230
1231 if (vma->vm_flags & VM_PFNMAP)
1232 return 1;
1233
1234 /*
1235 * Writing 1 to /proc/pid/clear_refs affects all pages.
1236 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages.
1237 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages.
1238 * Writing 4 to /proc/pid/clear_refs affects all pages.
1239 */
1240 if (cp->type == CLEAR_REFS_ANON && vma->vm_file)
1241 return 1;
1242 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file)
1243 return 1;
1244 return 0;
1245}
1246
1247static const struct mm_walk_ops clear_refs_walk_ops = {
1248 .pmd_entry = clear_refs_pte_range,
1249 .test_walk = clear_refs_test_walk,
1250};
1251
1252static ssize_t clear_refs_write(struct file *file, const char __user *buf,
1253 size_t count, loff_t *ppos)
1254{
1255 struct task_struct *task;
1256 char buffer[PROC_NUMBUF];
1257 struct mm_struct *mm;
1258 struct vm_area_struct *vma;
1259 enum clear_refs_types type;
1260 int itype;
1261 int rv;
1262
1263 memset(buffer, 0, sizeof(buffer));
1264 if (count > sizeof(buffer) - 1)
1265 count = sizeof(buffer) - 1;
1266 if (copy_from_user(buffer, buf, count))
1267 return -EFAULT;
1268 rv = kstrtoint(strstrip(buffer), 10, &itype);
1269 if (rv < 0)
1270 return rv;
1271 type = (enum clear_refs_types)itype;
1272 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
1273 return -EINVAL;
1274
1275 task = get_proc_task(file_inode(file));
1276 if (!task)
1277 return -ESRCH;
1278 mm = get_task_mm(task);
1279 if (mm) {
1280 MA_STATE(mas, &mm->mm_mt, 0, 0);
1281 struct mmu_notifier_range range;
1282 struct clear_refs_private cp = {
1283 .type = type,
1284 };
1285
1286 if (mmap_write_lock_killable(mm)) {
1287 count = -EINTR;
1288 goto out_mm;
1289 }
1290 if (type == CLEAR_REFS_MM_HIWATER_RSS) {
1291 /*
1292 * Writing 5 to /proc/pid/clear_refs resets the peak
1293 * resident set size to this mm's current rss value.
1294 */
1295 reset_mm_hiwater_rss(mm);
1296 goto out_unlock;
1297 }
1298
1299 if (type == CLEAR_REFS_SOFT_DIRTY) {
1300 mas_for_each(&mas, vma, ULONG_MAX) {
1301 if (!(vma->vm_flags & VM_SOFTDIRTY))
1302 continue;
1303 vma->vm_flags &= ~VM_SOFTDIRTY;
1304 vma_set_page_prot(vma);
1305 }
1306
1307 inc_tlb_flush_pending(mm);
1308 mmu_notifier_range_init(&range, MMU_NOTIFY_SOFT_DIRTY,
1309 0, NULL, mm, 0, -1UL);
1310 mmu_notifier_invalidate_range_start(&range);
1311 }
1312 walk_page_range(mm, 0, -1, &clear_refs_walk_ops, &cp);
1313 if (type == CLEAR_REFS_SOFT_DIRTY) {
1314 mmu_notifier_invalidate_range_end(&range);
1315 flush_tlb_mm(mm);
1316 dec_tlb_flush_pending(mm);
1317 }
1318out_unlock:
1319 mmap_write_unlock(mm);
1320out_mm:
1321 mmput(mm);
1322 }
1323 put_task_struct(task);
1324
1325 return count;
1326}
1327
1328const struct file_operations proc_clear_refs_operations = {
1329 .write = clear_refs_write,
1330 .llseek = noop_llseek,
1331};
1332
1333typedef struct {
1334 u64 pme;
1335} pagemap_entry_t;
1336
1337struct pagemapread {
1338 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */
1339 pagemap_entry_t *buffer;
1340 bool show_pfn;
1341};
1342
1343#define PAGEMAP_WALK_SIZE (PMD_SIZE)
1344#define PAGEMAP_WALK_MASK (PMD_MASK)
1345
1346#define PM_ENTRY_BYTES sizeof(pagemap_entry_t)
1347#define PM_PFRAME_BITS 55
1348#define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0)
1349#define PM_SOFT_DIRTY BIT_ULL(55)
1350#define PM_MMAP_EXCLUSIVE BIT_ULL(56)
1351#define PM_UFFD_WP BIT_ULL(57)
1352#define PM_FILE BIT_ULL(61)
1353#define PM_SWAP BIT_ULL(62)
1354#define PM_PRESENT BIT_ULL(63)
1355
1356#define PM_END_OF_BUFFER 1
1357
1358static inline pagemap_entry_t make_pme(u64 frame, u64 flags)
1359{
1360 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags };
1361}
1362
1363static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme,
1364 struct pagemapread *pm)
1365{
1366 pm->buffer[pm->pos++] = *pme;
1367 if (pm->pos >= pm->len)
1368 return PM_END_OF_BUFFER;
1369 return 0;
1370}
1371
1372static int pagemap_pte_hole(unsigned long start, unsigned long end,
1373 __always_unused int depth, struct mm_walk *walk)
1374{
1375 struct pagemapread *pm = walk->private;
1376 unsigned long addr = start;
1377 int err = 0;
1378
1379 while (addr < end) {
1380 struct vm_area_struct *vma = find_vma(walk->mm, addr);
1381 pagemap_entry_t pme = make_pme(0, 0);
1382 /* End of address space hole, which we mark as non-present. */
1383 unsigned long hole_end;
1384
1385 if (vma)
1386 hole_end = min(end, vma->vm_start);
1387 else
1388 hole_end = end;
1389
1390 for (; addr < hole_end; addr += PAGE_SIZE) {
1391 err = add_to_pagemap(addr, &pme, pm);
1392 if (err)
1393 goto out;
1394 }
1395
1396 if (!vma)
1397 break;
1398
1399 /* Addresses in the VMA. */
1400 if (vma->vm_flags & VM_SOFTDIRTY)
1401 pme = make_pme(0, PM_SOFT_DIRTY);
1402 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) {
1403 err = add_to_pagemap(addr, &pme, pm);
1404 if (err)
1405 goto out;
1406 }
1407 }
1408out:
1409 return err;
1410}
1411
1412static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm,
1413 struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1414{
1415 u64 frame = 0, flags = 0;
1416 struct page *page = NULL;
1417 bool migration = false;
1418
1419 if (pte_present(pte)) {
1420 if (pm->show_pfn)
1421 frame = pte_pfn(pte);
1422 flags |= PM_PRESENT;
1423 page = vm_normal_page(vma, addr, pte);
1424 if (pte_soft_dirty(pte))
1425 flags |= PM_SOFT_DIRTY;
1426 if (pte_uffd_wp(pte))
1427 flags |= PM_UFFD_WP;
1428 } else if (is_swap_pte(pte)) {
1429 swp_entry_t entry;
1430 if (pte_swp_soft_dirty(pte))
1431 flags |= PM_SOFT_DIRTY;
1432 if (pte_swp_uffd_wp(pte))
1433 flags |= PM_UFFD_WP;
1434 entry = pte_to_swp_entry(pte);
1435 if (pm->show_pfn) {
1436 pgoff_t offset;
1437 /*
1438 * For PFN swap offsets, keeping the offset field
1439 * to be PFN only to be compatible with old smaps.
1440 */
1441 if (is_pfn_swap_entry(entry))
1442 offset = swp_offset_pfn(entry);
1443 else
1444 offset = swp_offset(entry);
1445 frame = swp_type(entry) |
1446 (offset << MAX_SWAPFILES_SHIFT);
1447 }
1448 flags |= PM_SWAP;
1449 migration = is_migration_entry(entry);
1450 if (is_pfn_swap_entry(entry))
1451 page = pfn_swap_entry_to_page(entry);
1452 if (pte_marker_entry_uffd_wp(entry))
1453 flags |= PM_UFFD_WP;
1454 }
1455
1456 if (page && !PageAnon(page))
1457 flags |= PM_FILE;
1458 if (page && !migration && page_mapcount(page) == 1)
1459 flags |= PM_MMAP_EXCLUSIVE;
1460 if (vma->vm_flags & VM_SOFTDIRTY)
1461 flags |= PM_SOFT_DIRTY;
1462
1463 return make_pme(frame, flags);
1464}
1465
1466static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
1467 struct mm_walk *walk)
1468{
1469 struct vm_area_struct *vma = walk->vma;
1470 struct pagemapread *pm = walk->private;
1471 spinlock_t *ptl;
1472 pte_t *pte, *orig_pte;
1473 int err = 0;
1474#ifdef CONFIG_TRANSPARENT_HUGEPAGE
1475 bool migration = false;
1476
1477 ptl = pmd_trans_huge_lock(pmdp, vma);
1478 if (ptl) {
1479 u64 flags = 0, frame = 0;
1480 pmd_t pmd = *pmdp;
1481 struct page *page = NULL;
1482
1483 if (vma->vm_flags & VM_SOFTDIRTY)
1484 flags |= PM_SOFT_DIRTY;
1485
1486 if (pmd_present(pmd)) {
1487 page = pmd_page(pmd);
1488
1489 flags |= PM_PRESENT;
1490 if (pmd_soft_dirty(pmd))
1491 flags |= PM_SOFT_DIRTY;
1492 if (pmd_uffd_wp(pmd))
1493 flags |= PM_UFFD_WP;
1494 if (pm->show_pfn)
1495 frame = pmd_pfn(pmd) +
1496 ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1497 }
1498#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
1499 else if (is_swap_pmd(pmd)) {
1500 swp_entry_t entry = pmd_to_swp_entry(pmd);
1501 unsigned long offset;
1502
1503 if (pm->show_pfn) {
1504 if (is_pfn_swap_entry(entry))
1505 offset = swp_offset_pfn(entry);
1506 else
1507 offset = swp_offset(entry);
1508 offset = offset +
1509 ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1510 frame = swp_type(entry) |
1511 (offset << MAX_SWAPFILES_SHIFT);
1512 }
1513 flags |= PM_SWAP;
1514 if (pmd_swp_soft_dirty(pmd))
1515 flags |= PM_SOFT_DIRTY;
1516 if (pmd_swp_uffd_wp(pmd))
1517 flags |= PM_UFFD_WP;
1518 VM_BUG_ON(!is_pmd_migration_entry(pmd));
1519 migration = is_migration_entry(entry);
1520 page = pfn_swap_entry_to_page(entry);
1521 }
1522#endif
1523
1524 if (page && !migration && page_mapcount(page) == 1)
1525 flags |= PM_MMAP_EXCLUSIVE;
1526
1527 for (; addr != end; addr += PAGE_SIZE) {
1528 pagemap_entry_t pme = make_pme(frame, flags);
1529
1530 err = add_to_pagemap(addr, &pme, pm);
1531 if (err)
1532 break;
1533 if (pm->show_pfn) {
1534 if (flags & PM_PRESENT)
1535 frame++;
1536 else if (flags & PM_SWAP)
1537 frame += (1 << MAX_SWAPFILES_SHIFT);
1538 }
1539 }
1540 spin_unlock(ptl);
1541 return err;
1542 }
1543
1544 if (pmd_trans_unstable(pmdp))
1545 return 0;
1546#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1547
1548 /*
1549 * We can assume that @vma always points to a valid one and @end never
1550 * goes beyond vma->vm_end.
1551 */
1552 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl);
1553 for (; addr < end; pte++, addr += PAGE_SIZE) {
1554 pagemap_entry_t pme;
1555
1556 pme = pte_to_pagemap_entry(pm, vma, addr, *pte);
1557 err = add_to_pagemap(addr, &pme, pm);
1558 if (err)
1559 break;
1560 }
1561 pte_unmap_unlock(orig_pte, ptl);
1562
1563 cond_resched();
1564
1565 return err;
1566}
1567
1568#ifdef CONFIG_HUGETLB_PAGE
1569/* This function walks within one hugetlb entry in the single call */
1570static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask,
1571 unsigned long addr, unsigned long end,
1572 struct mm_walk *walk)
1573{
1574 struct pagemapread *pm = walk->private;
1575 struct vm_area_struct *vma = walk->vma;
1576 u64 flags = 0, frame = 0;
1577 int err = 0;
1578 pte_t pte;
1579
1580 if (vma->vm_flags & VM_SOFTDIRTY)
1581 flags |= PM_SOFT_DIRTY;
1582
1583 pte = huge_ptep_get(ptep);
1584 if (pte_present(pte)) {
1585 struct page *page = pte_page(pte);
1586
1587 if (!PageAnon(page))
1588 flags |= PM_FILE;
1589
1590 if (page_mapcount(page) == 1)
1591 flags |= PM_MMAP_EXCLUSIVE;
1592
1593 if (huge_pte_uffd_wp(pte))
1594 flags |= PM_UFFD_WP;
1595
1596 flags |= PM_PRESENT;
1597 if (pm->show_pfn)
1598 frame = pte_pfn(pte) +
1599 ((addr & ~hmask) >> PAGE_SHIFT);
1600 } else if (pte_swp_uffd_wp_any(pte)) {
1601 flags |= PM_UFFD_WP;
1602 }
1603
1604 for (; addr != end; addr += PAGE_SIZE) {
1605 pagemap_entry_t pme = make_pme(frame, flags);
1606
1607 err = add_to_pagemap(addr, &pme, pm);
1608 if (err)
1609 return err;
1610 if (pm->show_pfn && (flags & PM_PRESENT))
1611 frame++;
1612 }
1613
1614 cond_resched();
1615
1616 return err;
1617}
1618#else
1619#define pagemap_hugetlb_range NULL
1620#endif /* HUGETLB_PAGE */
1621
1622static const struct mm_walk_ops pagemap_ops = {
1623 .pmd_entry = pagemap_pmd_range,
1624 .pte_hole = pagemap_pte_hole,
1625 .hugetlb_entry = pagemap_hugetlb_range,
1626};
1627
1628/*
1629 * /proc/pid/pagemap - an array mapping virtual pages to pfns
1630 *
1631 * For each page in the address space, this file contains one 64-bit entry
1632 * consisting of the following:
1633 *
1634 * Bits 0-54 page frame number (PFN) if present
1635 * Bits 0-4 swap type if swapped
1636 * Bits 5-54 swap offset if swapped
1637 * Bit 55 pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst)
1638 * Bit 56 page exclusively mapped
1639 * Bit 57 pte is uffd-wp write-protected
1640 * Bits 58-60 zero
1641 * Bit 61 page is file-page or shared-anon
1642 * Bit 62 page swapped
1643 * Bit 63 page present
1644 *
1645 * If the page is not present but in swap, then the PFN contains an
1646 * encoding of the swap file number and the page's offset into the
1647 * swap. Unmapped pages return a null PFN. This allows determining
1648 * precisely which pages are mapped (or in swap) and comparing mapped
1649 * pages between processes.
1650 *
1651 * Efficient users of this interface will use /proc/pid/maps to
1652 * determine which areas of memory are actually mapped and llseek to
1653 * skip over unmapped regions.
1654 */
1655static ssize_t pagemap_read(struct file *file, char __user *buf,
1656 size_t count, loff_t *ppos)
1657{
1658 struct mm_struct *mm = file->private_data;
1659 struct pagemapread pm;
1660 unsigned long src;
1661 unsigned long svpfn;
1662 unsigned long start_vaddr;
1663 unsigned long end_vaddr;
1664 int ret = 0, copied = 0;
1665
1666 if (!mm || !mmget_not_zero(mm))
1667 goto out;
1668
1669 ret = -EINVAL;
1670 /* file position must be aligned */
1671 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
1672 goto out_mm;
1673
1674 ret = 0;
1675 if (!count)
1676 goto out_mm;
1677
1678 /* do not disclose physical addresses: attack vector */
1679 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN);
1680
1681 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
1682 pm.buffer = kmalloc_array(pm.len, PM_ENTRY_BYTES, GFP_KERNEL);
1683 ret = -ENOMEM;
1684 if (!pm.buffer)
1685 goto out_mm;
1686
1687 src = *ppos;
1688 svpfn = src / PM_ENTRY_BYTES;
1689 end_vaddr = mm->task_size;
1690
1691 /* watch out for wraparound */
1692 start_vaddr = end_vaddr;
1693 if (svpfn <= (ULONG_MAX >> PAGE_SHIFT))
1694 start_vaddr = untagged_addr(svpfn << PAGE_SHIFT);
1695
1696 /* Ensure the address is inside the task */
1697 if (start_vaddr > mm->task_size)
1698 start_vaddr = end_vaddr;
1699
1700 /*
1701 * The odds are that this will stop walking way
1702 * before end_vaddr, because the length of the
1703 * user buffer is tracked in "pm", and the walk
1704 * will stop when we hit the end of the buffer.
1705 */
1706 ret = 0;
1707 while (count && (start_vaddr < end_vaddr)) {
1708 int len;
1709 unsigned long end;
1710
1711 pm.pos = 0;
1712 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
1713 /* overflow ? */
1714 if (end < start_vaddr || end > end_vaddr)
1715 end = end_vaddr;
1716 ret = mmap_read_lock_killable(mm);
1717 if (ret)
1718 goto out_free;
1719 ret = walk_page_range(mm, start_vaddr, end, &pagemap_ops, &pm);
1720 mmap_read_unlock(mm);
1721 start_vaddr = end;
1722
1723 len = min(count, PM_ENTRY_BYTES * pm.pos);
1724 if (copy_to_user(buf, pm.buffer, len)) {
1725 ret = -EFAULT;
1726 goto out_free;
1727 }
1728 copied += len;
1729 buf += len;
1730 count -= len;
1731 }
1732 *ppos += copied;
1733 if (!ret || ret == PM_END_OF_BUFFER)
1734 ret = copied;
1735
1736out_free:
1737 kfree(pm.buffer);
1738out_mm:
1739 mmput(mm);
1740out:
1741 return ret;
1742}
1743
1744static int pagemap_open(struct inode *inode, struct file *file)
1745{
1746 struct mm_struct *mm;
1747
1748 mm = proc_mem_open(inode, PTRACE_MODE_READ);
1749 if (IS_ERR(mm))
1750 return PTR_ERR(mm);
1751 file->private_data = mm;
1752 return 0;
1753}
1754
1755static int pagemap_release(struct inode *inode, struct file *file)
1756{
1757 struct mm_struct *mm = file->private_data;
1758
1759 if (mm)
1760 mmdrop(mm);
1761 return 0;
1762}
1763
1764const struct file_operations proc_pagemap_operations = {
1765 .llseek = mem_lseek, /* borrow this */
1766 .read = pagemap_read,
1767 .open = pagemap_open,
1768 .release = pagemap_release,
1769};
1770#endif /* CONFIG_PROC_PAGE_MONITOR */
1771
1772#ifdef CONFIG_NUMA
1773
1774struct numa_maps {
1775 unsigned long pages;
1776 unsigned long anon;
1777 unsigned long active;
1778 unsigned long writeback;
1779 unsigned long mapcount_max;
1780 unsigned long dirty;
1781 unsigned long swapcache;
1782 unsigned long node[MAX_NUMNODES];
1783};
1784
1785struct numa_maps_private {
1786 struct proc_maps_private proc_maps;
1787 struct numa_maps md;
1788};
1789
1790static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
1791 unsigned long nr_pages)
1792{
1793 int count = page_mapcount(page);
1794
1795 md->pages += nr_pages;
1796 if (pte_dirty || PageDirty(page))
1797 md->dirty += nr_pages;
1798
1799 if (PageSwapCache(page))
1800 md->swapcache += nr_pages;
1801
1802 if (PageActive(page) || PageUnevictable(page))
1803 md->active += nr_pages;
1804
1805 if (PageWriteback(page))
1806 md->writeback += nr_pages;
1807
1808 if (PageAnon(page))
1809 md->anon += nr_pages;
1810
1811 if (count > md->mapcount_max)
1812 md->mapcount_max = count;
1813
1814 md->node[page_to_nid(page)] += nr_pages;
1815}
1816
1817static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
1818 unsigned long addr)
1819{
1820 struct page *page;
1821 int nid;
1822
1823 if (!pte_present(pte))
1824 return NULL;
1825
1826 page = vm_normal_page(vma, addr, pte);
1827 if (!page || is_zone_device_page(page))
1828 return NULL;
1829
1830 if (PageReserved(page))
1831 return NULL;
1832
1833 nid = page_to_nid(page);
1834 if (!node_isset(nid, node_states[N_MEMORY]))
1835 return NULL;
1836
1837 return page;
1838}
1839
1840#ifdef CONFIG_TRANSPARENT_HUGEPAGE
1841static struct page *can_gather_numa_stats_pmd(pmd_t pmd,
1842 struct vm_area_struct *vma,
1843 unsigned long addr)
1844{
1845 struct page *page;
1846 int nid;
1847
1848 if (!pmd_present(pmd))
1849 return NULL;
1850
1851 page = vm_normal_page_pmd(vma, addr, pmd);
1852 if (!page)
1853 return NULL;
1854
1855 if (PageReserved(page))
1856 return NULL;
1857
1858 nid = page_to_nid(page);
1859 if (!node_isset(nid, node_states[N_MEMORY]))
1860 return NULL;
1861
1862 return page;
1863}
1864#endif
1865
1866static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
1867 unsigned long end, struct mm_walk *walk)
1868{
1869 struct numa_maps *md = walk->private;
1870 struct vm_area_struct *vma = walk->vma;
1871 spinlock_t *ptl;
1872 pte_t *orig_pte;
1873 pte_t *pte;
1874
1875#ifdef CONFIG_TRANSPARENT_HUGEPAGE
1876 ptl = pmd_trans_huge_lock(pmd, vma);
1877 if (ptl) {
1878 struct page *page;
1879
1880 page = can_gather_numa_stats_pmd(*pmd, vma, addr);
1881 if (page)
1882 gather_stats(page, md, pmd_dirty(*pmd),
1883 HPAGE_PMD_SIZE/PAGE_SIZE);
1884 spin_unlock(ptl);
1885 return 0;
1886 }
1887
1888 if (pmd_trans_unstable(pmd))
1889 return 0;
1890#endif
1891 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
1892 do {
1893 struct page *page = can_gather_numa_stats(*pte, vma, addr);
1894 if (!page)
1895 continue;
1896 gather_stats(page, md, pte_dirty(*pte), 1);
1897
1898 } while (pte++, addr += PAGE_SIZE, addr != end);
1899 pte_unmap_unlock(orig_pte, ptl);
1900 cond_resched();
1901 return 0;
1902}
1903#ifdef CONFIG_HUGETLB_PAGE
1904static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1905 unsigned long addr, unsigned long end, struct mm_walk *walk)
1906{
1907 pte_t huge_pte = huge_ptep_get(pte);
1908 struct numa_maps *md;
1909 struct page *page;
1910
1911 if (!pte_present(huge_pte))
1912 return 0;
1913
1914 page = pte_page(huge_pte);
1915
1916 md = walk->private;
1917 gather_stats(page, md, pte_dirty(huge_pte), 1);
1918 return 0;
1919}
1920
1921#else
1922static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1923 unsigned long addr, unsigned long end, struct mm_walk *walk)
1924{
1925 return 0;
1926}
1927#endif
1928
1929static const struct mm_walk_ops show_numa_ops = {
1930 .hugetlb_entry = gather_hugetlb_stats,
1931 .pmd_entry = gather_pte_stats,
1932};
1933
1934/*
1935 * Display pages allocated per node and memory policy via /proc.
1936 */
1937static int show_numa_map(struct seq_file *m, void *v)
1938{
1939 struct numa_maps_private *numa_priv = m->private;
1940 struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
1941 struct vm_area_struct *vma = v;
1942 struct numa_maps *md = &numa_priv->md;
1943 struct file *file = vma->vm_file;
1944 struct mm_struct *mm = vma->vm_mm;
1945 struct mempolicy *pol;
1946 char buffer[64];
1947 int nid;
1948
1949 if (!mm)
1950 return 0;
1951
1952 /* Ensure we start with an empty set of numa_maps statistics. */
1953 memset(md, 0, sizeof(*md));
1954
1955 pol = __get_vma_policy(vma, vma->vm_start);
1956 if (pol) {
1957 mpol_to_str(buffer, sizeof(buffer), pol);
1958 mpol_cond_put(pol);
1959 } else {
1960 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy);
1961 }
1962
1963 seq_printf(m, "%08lx %s", vma->vm_start, buffer);
1964
1965 if (file) {
1966 seq_puts(m, " file=");
1967 seq_file_path(m, file, "\n\t= ");
1968 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1969 seq_puts(m, " heap");
1970 } else if (is_stack(vma)) {
1971 seq_puts(m, " stack");
1972 }
1973
1974 if (is_vm_hugetlb_page(vma))
1975 seq_puts(m, " huge");
1976
1977 /* mmap_lock is held by m_start */
1978 walk_page_vma(vma, &show_numa_ops, md);
1979
1980 if (!md->pages)
1981 goto out;
1982
1983 if (md->anon)
1984 seq_printf(m, " anon=%lu", md->anon);
1985
1986 if (md->dirty)
1987 seq_printf(m, " dirty=%lu", md->dirty);
1988
1989 if (md->pages != md->anon && md->pages != md->dirty)
1990 seq_printf(m, " mapped=%lu", md->pages);
1991
1992 if (md->mapcount_max > 1)
1993 seq_printf(m, " mapmax=%lu", md->mapcount_max);
1994
1995 if (md->swapcache)
1996 seq_printf(m, " swapcache=%lu", md->swapcache);
1997
1998 if (md->active < md->pages && !is_vm_hugetlb_page(vma))
1999 seq_printf(m, " active=%lu", md->active);
2000
2001 if (md->writeback)
2002 seq_printf(m, " writeback=%lu", md->writeback);
2003
2004 for_each_node_state(nid, N_MEMORY)
2005 if (md->node[nid])
2006 seq_printf(m, " N%d=%lu", nid, md->node[nid]);
2007
2008 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10);
2009out:
2010 seq_putc(m, '\n');
2011 return 0;
2012}
2013
2014static const struct seq_operations proc_pid_numa_maps_op = {
2015 .start = m_start,
2016 .next = m_next,
2017 .stop = m_stop,
2018 .show = show_numa_map,
2019};
2020
2021static int pid_numa_maps_open(struct inode *inode, struct file *file)
2022{
2023 return proc_maps_open(inode, file, &proc_pid_numa_maps_op,
2024 sizeof(struct numa_maps_private));
2025}
2026
2027const struct file_operations proc_pid_numa_maps_operations = {
2028 .open = pid_numa_maps_open,
2029 .read = seq_read,
2030 .llseek = seq_lseek,
2031 .release = proc_map_release,
2032};
2033
2034#endif /* CONFIG_NUMA */
1#include <linux/mm.h>
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
17#include <asm/elf.h>
18#include <asm/uaccess.h>
19#include <asm/tlbflush.h>
20#include "internal.h"
21
22void task_mem(struct seq_file *m, struct mm_struct *mm)
23{
24 unsigned long data, text, lib, swap;
25 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
26
27 /*
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.
33 */
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;
40
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);
45 seq_printf(m,
46 "VmPeak:\t%8lu kB\n"
47 "VmSize:\t%8lu kB\n"
48 "VmLck:\t%8lu kB\n"
49 "VmPin:\t%8lu kB\n"
50 "VmHWM:\t%8lu kB\n"
51 "VmRSS:\t%8lu kB\n"
52 "VmData:\t%8lu kB\n"
53 "VmStk:\t%8lu kB\n"
54 "VmExe:\t%8lu kB\n"
55 "VmLib:\t%8lu kB\n"
56 "VmPTE:\t%8lu kB\n"
57 "VmSwap:\t%8lu kB\n",
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));
69}
70
71unsigned long task_vsize(struct mm_struct *mm)
72{
73 return PAGE_SIZE * mm->total_vm;
74}
75
76unsigned long task_statm(struct mm_struct *mm,
77 unsigned long *shared, unsigned long *text,
78 unsigned long *data, unsigned long *resident)
79{
80 *shared = get_mm_counter(mm, MM_FILEPAGES);
81 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
82 >> PAGE_SHIFT;
83 *data = mm->total_vm - mm->shared_vm;
84 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
85 return mm->total_vm;
86}
87
88#ifdef CONFIG_NUMA
89/*
90 * These functions are for numa_maps but called in generic **maps seq_file
91 * ->start(), ->stop() ops.
92 *
93 * numa_maps scans all vmas under mmap_sem and checks their mempolicy.
94 * Each mempolicy object is controlled by reference counting. The problem here
95 * is how to avoid accessing dead mempolicy object.
96 *
97 * Because we're holding mmap_sem while reading seq_file, it's safe to access
98 * each vma's mempolicy, no vma objects will never drop refs to mempolicy.
99 *
100 * A task's mempolicy (task->mempolicy) has different behavior. task->mempolicy
101 * is set and replaced under mmap_sem but unrefed and cleared under task_lock().
102 * So, without task_lock(), we cannot trust get_vma_policy() because we cannot
103 * gurantee the task never exits under us. But taking task_lock() around
104 * get_vma_plicy() causes lock order problem.
105 *
106 * To access task->mempolicy without lock, we hold a reference count of an
107 * object pointed by task->mempolicy and remember it. This will guarantee
108 * that task->mempolicy points to an alive object or NULL in numa_maps accesses.
109 */
110static void hold_task_mempolicy(struct proc_maps_private *priv)
111{
112 struct task_struct *task = priv->task;
113
114 task_lock(task);
115 priv->task_mempolicy = task->mempolicy;
116 mpol_get(priv->task_mempolicy);
117 task_unlock(task);
118}
119static void release_task_mempolicy(struct proc_maps_private *priv)
120{
121 mpol_put(priv->task_mempolicy);
122}
123#else
124static void hold_task_mempolicy(struct proc_maps_private *priv)
125{
126}
127static void release_task_mempolicy(struct proc_maps_private *priv)
128{
129}
130#endif
131
132static void vma_stop(struct proc_maps_private *priv, struct vm_area_struct *vma)
133{
134 if (vma && vma != priv->tail_vma) {
135 struct mm_struct *mm = vma->vm_mm;
136 release_task_mempolicy(priv);
137 up_read(&mm->mmap_sem);
138 mmput(mm);
139 }
140}
141
142static void *m_start(struct seq_file *m, loff_t *pos)
143{
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, *tail_vma = NULL;
148 loff_t l = *pos;
149
150 /* Clear the per syscall fields in priv */
151 priv->task = NULL;
152 priv->tail_vma = NULL;
153
154 /*
155 * We remember last_addr rather than next_addr to hit with
156 * vmacache most of the time. We have zero last_addr at
157 * the beginning and also after lseek. We will have -1 last_addr
158 * after the end of the vmas.
159 */
160
161 if (last_addr == -1UL)
162 return NULL;
163
164 priv->task = get_pid_task(priv->pid, PIDTYPE_PID);
165 if (!priv->task)
166 return ERR_PTR(-ESRCH);
167
168 mm = mm_access(priv->task, PTRACE_MODE_READ);
169 if (!mm || IS_ERR(mm))
170 return mm;
171 down_read(&mm->mmap_sem);
172
173 tail_vma = get_gate_vma(priv->task->mm);
174 priv->tail_vma = tail_vma;
175 hold_task_mempolicy(priv);
176 /* Start with last addr hint */
177 vma = find_vma(mm, last_addr);
178 if (last_addr && vma) {
179 vma = vma->vm_next;
180 goto out;
181 }
182
183 /*
184 * Check the vma index is within the range and do
185 * sequential scan until m_index.
186 */
187 vma = NULL;
188 if ((unsigned long)l < mm->map_count) {
189 vma = mm->mmap;
190 while (l-- && vma)
191 vma = vma->vm_next;
192 goto out;
193 }
194
195 if (l != mm->map_count)
196 tail_vma = NULL; /* After gate vma */
197
198out:
199 if (vma)
200 return vma;
201
202 release_task_mempolicy(priv);
203 /* End of vmas has been reached */
204 m->version = (tail_vma != NULL)? 0: -1UL;
205 up_read(&mm->mmap_sem);
206 mmput(mm);
207 return tail_vma;
208}
209
210static void *m_next(struct seq_file *m, void *v, loff_t *pos)
211{
212 struct proc_maps_private *priv = m->private;
213 struct vm_area_struct *vma = v;
214 struct vm_area_struct *tail_vma = priv->tail_vma;
215
216 (*pos)++;
217 if (vma && (vma != tail_vma) && vma->vm_next)
218 return vma->vm_next;
219 vma_stop(priv, vma);
220 return (vma != tail_vma)? tail_vma: NULL;
221}
222
223static void m_stop(struct seq_file *m, void *v)
224{
225 struct proc_maps_private *priv = m->private;
226 struct vm_area_struct *vma = v;
227
228 if (!IS_ERR(vma))
229 vma_stop(priv, vma);
230 if (priv->task)
231 put_task_struct(priv->task);
232}
233
234static int do_maps_open(struct inode *inode, struct file *file,
235 const struct seq_operations *ops)
236{
237 struct proc_maps_private *priv;
238 int ret = -ENOMEM;
239 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
240 if (priv) {
241 priv->pid = proc_pid(inode);
242 ret = seq_open(file, ops);
243 if (!ret) {
244 struct seq_file *m = file->private_data;
245 m->private = priv;
246 } else {
247 kfree(priv);
248 }
249 }
250 return ret;
251}
252
253static void
254show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid)
255{
256 struct mm_struct *mm = vma->vm_mm;
257 struct file *file = vma->vm_file;
258 struct proc_maps_private *priv = m->private;
259 struct task_struct *task = priv->task;
260 vm_flags_t flags = vma->vm_flags;
261 unsigned long ino = 0;
262 unsigned long long pgoff = 0;
263 unsigned long start, end;
264 dev_t dev = 0;
265 const char *name = NULL;
266
267 if (file) {
268 struct inode *inode = file_inode(vma->vm_file);
269 dev = inode->i_sb->s_dev;
270 ino = inode->i_ino;
271 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
272 }
273
274 /* We don't show the stack guard page in /proc/maps */
275 start = vma->vm_start;
276 if (stack_guard_page_start(vma, start))
277 start += PAGE_SIZE;
278 end = vma->vm_end;
279 if (stack_guard_page_end(vma, end))
280 end -= PAGE_SIZE;
281
282 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
283 seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu ",
284 start,
285 end,
286 flags & VM_READ ? 'r' : '-',
287 flags & VM_WRITE ? 'w' : '-',
288 flags & VM_EXEC ? 'x' : '-',
289 flags & VM_MAYSHARE ? 's' : 'p',
290 pgoff,
291 MAJOR(dev), MINOR(dev), ino);
292
293 /*
294 * Print the dentry name for named mappings, and a
295 * special [heap] marker for the heap:
296 */
297 if (file) {
298 seq_pad(m, ' ');
299 seq_path(m, &file->f_path, "\n");
300 goto done;
301 }
302
303 name = arch_vma_name(vma);
304 if (!name) {
305 pid_t tid;
306
307 if (!mm) {
308 name = "[vdso]";
309 goto done;
310 }
311
312 if (vma->vm_start <= mm->brk &&
313 vma->vm_end >= mm->start_brk) {
314 name = "[heap]";
315 goto done;
316 }
317
318 tid = vm_is_stack(task, vma, is_pid);
319
320 if (tid != 0) {
321 /*
322 * Thread stack in /proc/PID/task/TID/maps or
323 * the main process stack.
324 */
325 if (!is_pid || (vma->vm_start <= mm->start_stack &&
326 vma->vm_end >= mm->start_stack)) {
327 name = "[stack]";
328 } else {
329 /* Thread stack in /proc/PID/maps */
330 seq_pad(m, ' ');
331 seq_printf(m, "[stack:%d]", tid);
332 }
333 }
334 }
335
336done:
337 if (name) {
338 seq_pad(m, ' ');
339 seq_puts(m, name);
340 }
341 seq_putc(m, '\n');
342}
343
344static int show_map(struct seq_file *m, void *v, int is_pid)
345{
346 struct vm_area_struct *vma = v;
347 struct proc_maps_private *priv = m->private;
348 struct task_struct *task = priv->task;
349
350 show_map_vma(m, vma, is_pid);
351
352 if (m->count < m->size) /* vma is copied successfully */
353 m->version = (vma != get_gate_vma(task->mm))
354 ? vma->vm_start : 0;
355 return 0;
356}
357
358static int show_pid_map(struct seq_file *m, void *v)
359{
360 return show_map(m, v, 1);
361}
362
363static int show_tid_map(struct seq_file *m, void *v)
364{
365 return show_map(m, v, 0);
366}
367
368static const struct seq_operations proc_pid_maps_op = {
369 .start = m_start,
370 .next = m_next,
371 .stop = m_stop,
372 .show = show_pid_map
373};
374
375static const struct seq_operations proc_tid_maps_op = {
376 .start = m_start,
377 .next = m_next,
378 .stop = m_stop,
379 .show = show_tid_map
380};
381
382static int pid_maps_open(struct inode *inode, struct file *file)
383{
384 return do_maps_open(inode, file, &proc_pid_maps_op);
385}
386
387static int tid_maps_open(struct inode *inode, struct file *file)
388{
389 return do_maps_open(inode, file, &proc_tid_maps_op);
390}
391
392const struct file_operations proc_pid_maps_operations = {
393 .open = pid_maps_open,
394 .read = seq_read,
395 .llseek = seq_lseek,
396 .release = seq_release_private,
397};
398
399const struct file_operations proc_tid_maps_operations = {
400 .open = tid_maps_open,
401 .read = seq_read,
402 .llseek = seq_lseek,
403 .release = seq_release_private,
404};
405
406/*
407 * Proportional Set Size(PSS): my share of RSS.
408 *
409 * PSS of a process is the count of pages it has in memory, where each
410 * page is divided by the number of processes sharing it. So if a
411 * process has 1000 pages all to itself, and 1000 shared with one other
412 * process, its PSS will be 1500.
413 *
414 * To keep (accumulated) division errors low, we adopt a 64bit
415 * fixed-point pss counter to minimize division errors. So (pss >>
416 * PSS_SHIFT) would be the real byte count.
417 *
418 * A shift of 12 before division means (assuming 4K page size):
419 * - 1M 3-user-pages add up to 8KB errors;
420 * - supports mapcount up to 2^24, or 16M;
421 * - supports PSS up to 2^52 bytes, or 4PB.
422 */
423#define PSS_SHIFT 12
424
425#ifdef CONFIG_PROC_PAGE_MONITOR
426struct mem_size_stats {
427 struct vm_area_struct *vma;
428 unsigned long resident;
429 unsigned long shared_clean;
430 unsigned long shared_dirty;
431 unsigned long private_clean;
432 unsigned long private_dirty;
433 unsigned long referenced;
434 unsigned long anonymous;
435 unsigned long anonymous_thp;
436 unsigned long swap;
437 unsigned long nonlinear;
438 u64 pss;
439};
440
441
442static void smaps_pte_entry(pte_t ptent, unsigned long addr,
443 unsigned long ptent_size, struct mm_walk *walk)
444{
445 struct mem_size_stats *mss = walk->private;
446 struct vm_area_struct *vma = mss->vma;
447 pgoff_t pgoff = linear_page_index(vma, addr);
448 struct page *page = NULL;
449 int mapcount;
450
451 if (pte_present(ptent)) {
452 page = vm_normal_page(vma, addr, ptent);
453 } else if (is_swap_pte(ptent)) {
454 swp_entry_t swpent = pte_to_swp_entry(ptent);
455
456 if (!non_swap_entry(swpent))
457 mss->swap += ptent_size;
458 else if (is_migration_entry(swpent))
459 page = migration_entry_to_page(swpent);
460 } else if (pte_file(ptent)) {
461 if (pte_to_pgoff(ptent) != pgoff)
462 mss->nonlinear += ptent_size;
463 }
464
465 if (!page)
466 return;
467
468 if (PageAnon(page))
469 mss->anonymous += ptent_size;
470
471 if (page->index != pgoff)
472 mss->nonlinear += ptent_size;
473
474 mss->resident += ptent_size;
475 /* Accumulate the size in pages that have been accessed. */
476 if (pte_young(ptent) || PageReferenced(page))
477 mss->referenced += ptent_size;
478 mapcount = page_mapcount(page);
479 if (mapcount >= 2) {
480 if (pte_dirty(ptent) || PageDirty(page))
481 mss->shared_dirty += ptent_size;
482 else
483 mss->shared_clean += ptent_size;
484 mss->pss += (ptent_size << PSS_SHIFT) / mapcount;
485 } else {
486 if (pte_dirty(ptent) || PageDirty(page))
487 mss->private_dirty += ptent_size;
488 else
489 mss->private_clean += ptent_size;
490 mss->pss += (ptent_size << PSS_SHIFT);
491 }
492}
493
494static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
495 struct mm_walk *walk)
496{
497 struct mem_size_stats *mss = walk->private;
498 struct vm_area_struct *vma = mss->vma;
499 pte_t *pte;
500 spinlock_t *ptl;
501
502 if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
503 smaps_pte_entry(*(pte_t *)pmd, addr, HPAGE_PMD_SIZE, walk);
504 spin_unlock(ptl);
505 mss->anonymous_thp += HPAGE_PMD_SIZE;
506 return 0;
507 }
508
509 if (pmd_trans_unstable(pmd))
510 return 0;
511 /*
512 * The mmap_sem held all the way back in m_start() is what
513 * keeps khugepaged out of here and from collapsing things
514 * in here.
515 */
516 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
517 for (; addr != end; pte++, addr += PAGE_SIZE)
518 smaps_pte_entry(*pte, addr, PAGE_SIZE, walk);
519 pte_unmap_unlock(pte - 1, ptl);
520 cond_resched();
521 return 0;
522}
523
524static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
525{
526 /*
527 * Don't forget to update Documentation/ on changes.
528 */
529 static const char mnemonics[BITS_PER_LONG][2] = {
530 /*
531 * In case if we meet a flag we don't know about.
532 */
533 [0 ... (BITS_PER_LONG-1)] = "??",
534
535 [ilog2(VM_READ)] = "rd",
536 [ilog2(VM_WRITE)] = "wr",
537 [ilog2(VM_EXEC)] = "ex",
538 [ilog2(VM_SHARED)] = "sh",
539 [ilog2(VM_MAYREAD)] = "mr",
540 [ilog2(VM_MAYWRITE)] = "mw",
541 [ilog2(VM_MAYEXEC)] = "me",
542 [ilog2(VM_MAYSHARE)] = "ms",
543 [ilog2(VM_GROWSDOWN)] = "gd",
544 [ilog2(VM_PFNMAP)] = "pf",
545 [ilog2(VM_DENYWRITE)] = "dw",
546 [ilog2(VM_LOCKED)] = "lo",
547 [ilog2(VM_IO)] = "io",
548 [ilog2(VM_SEQ_READ)] = "sr",
549 [ilog2(VM_RAND_READ)] = "rr",
550 [ilog2(VM_DONTCOPY)] = "dc",
551 [ilog2(VM_DONTEXPAND)] = "de",
552 [ilog2(VM_ACCOUNT)] = "ac",
553 [ilog2(VM_NORESERVE)] = "nr",
554 [ilog2(VM_HUGETLB)] = "ht",
555 [ilog2(VM_NONLINEAR)] = "nl",
556 [ilog2(VM_ARCH_1)] = "ar",
557 [ilog2(VM_DONTDUMP)] = "dd",
558#ifdef CONFIG_MEM_SOFT_DIRTY
559 [ilog2(VM_SOFTDIRTY)] = "sd",
560#endif
561 [ilog2(VM_MIXEDMAP)] = "mm",
562 [ilog2(VM_HUGEPAGE)] = "hg",
563 [ilog2(VM_NOHUGEPAGE)] = "nh",
564 [ilog2(VM_MERGEABLE)] = "mg",
565 };
566 size_t i;
567
568 seq_puts(m, "VmFlags: ");
569 for (i = 0; i < BITS_PER_LONG; i++) {
570 if (vma->vm_flags & (1UL << i)) {
571 seq_printf(m, "%c%c ",
572 mnemonics[i][0], mnemonics[i][1]);
573 }
574 }
575 seq_putc(m, '\n');
576}
577
578static int show_smap(struct seq_file *m, void *v, int is_pid)
579{
580 struct proc_maps_private *priv = m->private;
581 struct task_struct *task = priv->task;
582 struct vm_area_struct *vma = v;
583 struct mem_size_stats mss;
584 struct mm_walk smaps_walk = {
585 .pmd_entry = smaps_pte_range,
586 .mm = vma->vm_mm,
587 .private = &mss,
588 };
589
590 memset(&mss, 0, sizeof mss);
591 mss.vma = vma;
592 /* mmap_sem is held in m_start */
593 if (vma->vm_mm && !is_vm_hugetlb_page(vma))
594 walk_page_range(vma->vm_start, vma->vm_end, &smaps_walk);
595
596 show_map_vma(m, vma, is_pid);
597
598 seq_printf(m,
599 "Size: %8lu kB\n"
600 "Rss: %8lu kB\n"
601 "Pss: %8lu kB\n"
602 "Shared_Clean: %8lu kB\n"
603 "Shared_Dirty: %8lu kB\n"
604 "Private_Clean: %8lu kB\n"
605 "Private_Dirty: %8lu kB\n"
606 "Referenced: %8lu kB\n"
607 "Anonymous: %8lu kB\n"
608 "AnonHugePages: %8lu kB\n"
609 "Swap: %8lu kB\n"
610 "KernelPageSize: %8lu kB\n"
611 "MMUPageSize: %8lu kB\n"
612 "Locked: %8lu kB\n",
613 (vma->vm_end - vma->vm_start) >> 10,
614 mss.resident >> 10,
615 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)),
616 mss.shared_clean >> 10,
617 mss.shared_dirty >> 10,
618 mss.private_clean >> 10,
619 mss.private_dirty >> 10,
620 mss.referenced >> 10,
621 mss.anonymous >> 10,
622 mss.anonymous_thp >> 10,
623 mss.swap >> 10,
624 vma_kernel_pagesize(vma) >> 10,
625 vma_mmu_pagesize(vma) >> 10,
626 (vma->vm_flags & VM_LOCKED) ?
627 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0);
628
629 if (vma->vm_flags & VM_NONLINEAR)
630 seq_printf(m, "Nonlinear: %8lu kB\n",
631 mss.nonlinear >> 10);
632
633 show_smap_vma_flags(m, vma);
634
635 if (m->count < m->size) /* vma is copied successfully */
636 m->version = (vma != get_gate_vma(task->mm))
637 ? vma->vm_start : 0;
638 return 0;
639}
640
641static int show_pid_smap(struct seq_file *m, void *v)
642{
643 return show_smap(m, v, 1);
644}
645
646static int show_tid_smap(struct seq_file *m, void *v)
647{
648 return show_smap(m, v, 0);
649}
650
651static const struct seq_operations proc_pid_smaps_op = {
652 .start = m_start,
653 .next = m_next,
654 .stop = m_stop,
655 .show = show_pid_smap
656};
657
658static const struct seq_operations proc_tid_smaps_op = {
659 .start = m_start,
660 .next = m_next,
661 .stop = m_stop,
662 .show = show_tid_smap
663};
664
665static int pid_smaps_open(struct inode *inode, struct file *file)
666{
667 return do_maps_open(inode, file, &proc_pid_smaps_op);
668}
669
670static int tid_smaps_open(struct inode *inode, struct file *file)
671{
672 return do_maps_open(inode, file, &proc_tid_smaps_op);
673}
674
675const struct file_operations proc_pid_smaps_operations = {
676 .open = pid_smaps_open,
677 .read = seq_read,
678 .llseek = seq_lseek,
679 .release = seq_release_private,
680};
681
682const struct file_operations proc_tid_smaps_operations = {
683 .open = tid_smaps_open,
684 .read = seq_read,
685 .llseek = seq_lseek,
686 .release = seq_release_private,
687};
688
689/*
690 * We do not want to have constant page-shift bits sitting in
691 * pagemap entries and are about to reuse them some time soon.
692 *
693 * Here's the "migration strategy":
694 * 1. when the system boots these bits remain what they are,
695 * but a warning about future change is printed in log;
696 * 2. once anyone clears soft-dirty bits via clear_refs file,
697 * these flag is set to denote, that user is aware of the
698 * new API and those page-shift bits change their meaning.
699 * The respective warning is printed in dmesg;
700 * 3. In a couple of releases we will remove all the mentions
701 * of page-shift in pagemap entries.
702 */
703
704static bool soft_dirty_cleared __read_mostly;
705
706enum clear_refs_types {
707 CLEAR_REFS_ALL = 1,
708 CLEAR_REFS_ANON,
709 CLEAR_REFS_MAPPED,
710 CLEAR_REFS_SOFT_DIRTY,
711 CLEAR_REFS_LAST,
712};
713
714struct clear_refs_private {
715 struct vm_area_struct *vma;
716 enum clear_refs_types type;
717};
718
719static inline void clear_soft_dirty(struct vm_area_struct *vma,
720 unsigned long addr, pte_t *pte)
721{
722#ifdef CONFIG_MEM_SOFT_DIRTY
723 /*
724 * The soft-dirty tracker uses #PF-s to catch writes
725 * to pages, so write-protect the pte as well. See the
726 * Documentation/vm/soft-dirty.txt for full description
727 * of how soft-dirty works.
728 */
729 pte_t ptent = *pte;
730
731 if (pte_present(ptent)) {
732 ptent = pte_wrprotect(ptent);
733 ptent = pte_clear_flags(ptent, _PAGE_SOFT_DIRTY);
734 } else if (is_swap_pte(ptent)) {
735 ptent = pte_swp_clear_soft_dirty(ptent);
736 } else if (pte_file(ptent)) {
737 ptent = pte_file_clear_soft_dirty(ptent);
738 }
739
740 if (vma->vm_flags & VM_SOFTDIRTY)
741 vma->vm_flags &= ~VM_SOFTDIRTY;
742
743 set_pte_at(vma->vm_mm, addr, pte, ptent);
744#endif
745}
746
747static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
748 unsigned long end, struct mm_walk *walk)
749{
750 struct clear_refs_private *cp = walk->private;
751 struct vm_area_struct *vma = cp->vma;
752 pte_t *pte, ptent;
753 spinlock_t *ptl;
754 struct page *page;
755
756 split_huge_page_pmd(vma, addr, pmd);
757 if (pmd_trans_unstable(pmd))
758 return 0;
759
760 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
761 for (; addr != end; pte++, addr += PAGE_SIZE) {
762 ptent = *pte;
763
764 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
765 clear_soft_dirty(vma, addr, pte);
766 continue;
767 }
768
769 if (!pte_present(ptent))
770 continue;
771
772 page = vm_normal_page(vma, addr, ptent);
773 if (!page)
774 continue;
775
776 /* Clear accessed and referenced bits. */
777 ptep_test_and_clear_young(vma, addr, pte);
778 ClearPageReferenced(page);
779 }
780 pte_unmap_unlock(pte - 1, ptl);
781 cond_resched();
782 return 0;
783}
784
785static ssize_t clear_refs_write(struct file *file, const char __user *buf,
786 size_t count, loff_t *ppos)
787{
788 struct task_struct *task;
789 char buffer[PROC_NUMBUF];
790 struct mm_struct *mm;
791 struct vm_area_struct *vma;
792 enum clear_refs_types type;
793 int itype;
794 int rv;
795
796 memset(buffer, 0, sizeof(buffer));
797 if (count > sizeof(buffer) - 1)
798 count = sizeof(buffer) - 1;
799 if (copy_from_user(buffer, buf, count))
800 return -EFAULT;
801 rv = kstrtoint(strstrip(buffer), 10, &itype);
802 if (rv < 0)
803 return rv;
804 type = (enum clear_refs_types)itype;
805 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
806 return -EINVAL;
807
808 if (type == CLEAR_REFS_SOFT_DIRTY) {
809 soft_dirty_cleared = true;
810 pr_warn_once("The pagemap bits 55-60 has changed their meaning! "
811 "See the linux/Documentation/vm/pagemap.txt for details.\n");
812 }
813
814 task = get_proc_task(file_inode(file));
815 if (!task)
816 return -ESRCH;
817 mm = get_task_mm(task);
818 if (mm) {
819 struct clear_refs_private cp = {
820 .type = type,
821 };
822 struct mm_walk clear_refs_walk = {
823 .pmd_entry = clear_refs_pte_range,
824 .mm = mm,
825 .private = &cp,
826 };
827 down_read(&mm->mmap_sem);
828 if (type == CLEAR_REFS_SOFT_DIRTY)
829 mmu_notifier_invalidate_range_start(mm, 0, -1);
830 for (vma = mm->mmap; vma; vma = vma->vm_next) {
831 cp.vma = vma;
832 if (is_vm_hugetlb_page(vma))
833 continue;
834 /*
835 * Writing 1 to /proc/pid/clear_refs affects all pages.
836 *
837 * Writing 2 to /proc/pid/clear_refs only affects
838 * Anonymous pages.
839 *
840 * Writing 3 to /proc/pid/clear_refs only affects file
841 * mapped pages.
842 */
843 if (type == CLEAR_REFS_ANON && vma->vm_file)
844 continue;
845 if (type == CLEAR_REFS_MAPPED && !vma->vm_file)
846 continue;
847 walk_page_range(vma->vm_start, vma->vm_end,
848 &clear_refs_walk);
849 }
850 if (type == CLEAR_REFS_SOFT_DIRTY)
851 mmu_notifier_invalidate_range_end(mm, 0, -1);
852 flush_tlb_mm(mm);
853 up_read(&mm->mmap_sem);
854 mmput(mm);
855 }
856 put_task_struct(task);
857
858 return count;
859}
860
861const struct file_operations proc_clear_refs_operations = {
862 .write = clear_refs_write,
863 .llseek = noop_llseek,
864};
865
866typedef struct {
867 u64 pme;
868} pagemap_entry_t;
869
870struct pagemapread {
871 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */
872 pagemap_entry_t *buffer;
873 bool v2;
874};
875
876#define PAGEMAP_WALK_SIZE (PMD_SIZE)
877#define PAGEMAP_WALK_MASK (PMD_MASK)
878
879#define PM_ENTRY_BYTES sizeof(pagemap_entry_t)
880#define PM_STATUS_BITS 3
881#define PM_STATUS_OFFSET (64 - PM_STATUS_BITS)
882#define PM_STATUS_MASK (((1LL << PM_STATUS_BITS) - 1) << PM_STATUS_OFFSET)
883#define PM_STATUS(nr) (((nr) << PM_STATUS_OFFSET) & PM_STATUS_MASK)
884#define PM_PSHIFT_BITS 6
885#define PM_PSHIFT_OFFSET (PM_STATUS_OFFSET - PM_PSHIFT_BITS)
886#define PM_PSHIFT_MASK (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET)
887#define __PM_PSHIFT(x) (((u64) (x) << PM_PSHIFT_OFFSET) & PM_PSHIFT_MASK)
888#define PM_PFRAME_MASK ((1LL << PM_PSHIFT_OFFSET) - 1)
889#define PM_PFRAME(x) ((x) & PM_PFRAME_MASK)
890/* in "new" pagemap pshift bits are occupied with more status bits */
891#define PM_STATUS2(v2, x) (__PM_PSHIFT(v2 ? x : PAGE_SHIFT))
892
893#define __PM_SOFT_DIRTY (1LL)
894#define PM_PRESENT PM_STATUS(4LL)
895#define PM_SWAP PM_STATUS(2LL)
896#define PM_FILE PM_STATUS(1LL)
897#define PM_NOT_PRESENT(v2) PM_STATUS2(v2, 0)
898#define PM_END_OF_BUFFER 1
899
900static inline pagemap_entry_t make_pme(u64 val)
901{
902 return (pagemap_entry_t) { .pme = val };
903}
904
905static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme,
906 struct pagemapread *pm)
907{
908 pm->buffer[pm->pos++] = *pme;
909 if (pm->pos >= pm->len)
910 return PM_END_OF_BUFFER;
911 return 0;
912}
913
914static int pagemap_pte_hole(unsigned long start, unsigned long end,
915 struct mm_walk *walk)
916{
917 struct pagemapread *pm = walk->private;
918 unsigned long addr;
919 int err = 0;
920 pagemap_entry_t pme = make_pme(PM_NOT_PRESENT(pm->v2));
921
922 for (addr = start; addr < end; addr += PAGE_SIZE) {
923 err = add_to_pagemap(addr, &pme, pm);
924 if (err)
925 break;
926 }
927 return err;
928}
929
930static void pte_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm,
931 struct vm_area_struct *vma, unsigned long addr, pte_t pte)
932{
933 u64 frame, flags;
934 struct page *page = NULL;
935 int flags2 = 0;
936
937 if (pte_present(pte)) {
938 frame = pte_pfn(pte);
939 flags = PM_PRESENT;
940 page = vm_normal_page(vma, addr, pte);
941 if (pte_soft_dirty(pte))
942 flags2 |= __PM_SOFT_DIRTY;
943 } else if (is_swap_pte(pte)) {
944 swp_entry_t entry;
945 if (pte_swp_soft_dirty(pte))
946 flags2 |= __PM_SOFT_DIRTY;
947 entry = pte_to_swp_entry(pte);
948 frame = swp_type(entry) |
949 (swp_offset(entry) << MAX_SWAPFILES_SHIFT);
950 flags = PM_SWAP;
951 if (is_migration_entry(entry))
952 page = migration_entry_to_page(entry);
953 } else {
954 if (vma->vm_flags & VM_SOFTDIRTY)
955 flags2 |= __PM_SOFT_DIRTY;
956 *pme = make_pme(PM_NOT_PRESENT(pm->v2) | PM_STATUS2(pm->v2, flags2));
957 return;
958 }
959
960 if (page && !PageAnon(page))
961 flags |= PM_FILE;
962 if ((vma->vm_flags & VM_SOFTDIRTY))
963 flags2 |= __PM_SOFT_DIRTY;
964
965 *pme = make_pme(PM_PFRAME(frame) | PM_STATUS2(pm->v2, flags2) | flags);
966}
967
968#ifdef CONFIG_TRANSPARENT_HUGEPAGE
969static void thp_pmd_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm,
970 pmd_t pmd, int offset, int pmd_flags2)
971{
972 /*
973 * Currently pmd for thp is always present because thp can not be
974 * swapped-out, migrated, or HWPOISONed (split in such cases instead.)
975 * This if-check is just to prepare for future implementation.
976 */
977 if (pmd_present(pmd))
978 *pme = make_pme(PM_PFRAME(pmd_pfn(pmd) + offset)
979 | PM_STATUS2(pm->v2, pmd_flags2) | PM_PRESENT);
980 else
981 *pme = make_pme(PM_NOT_PRESENT(pm->v2) | PM_STATUS2(pm->v2, pmd_flags2));
982}
983#else
984static inline void thp_pmd_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm,
985 pmd_t pmd, int offset, int pmd_flags2)
986{
987}
988#endif
989
990static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
991 struct mm_walk *walk)
992{
993 struct vm_area_struct *vma;
994 struct pagemapread *pm = walk->private;
995 spinlock_t *ptl;
996 pte_t *pte;
997 int err = 0;
998 pagemap_entry_t pme = make_pme(PM_NOT_PRESENT(pm->v2));
999
1000 /* find the first VMA at or above 'addr' */
1001 vma = find_vma(walk->mm, addr);
1002 if (vma && pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
1003 int pmd_flags2;
1004
1005 if ((vma->vm_flags & VM_SOFTDIRTY) || pmd_soft_dirty(*pmd))
1006 pmd_flags2 = __PM_SOFT_DIRTY;
1007 else
1008 pmd_flags2 = 0;
1009
1010 for (; addr != end; addr += PAGE_SIZE) {
1011 unsigned long offset;
1012
1013 offset = (addr & ~PAGEMAP_WALK_MASK) >>
1014 PAGE_SHIFT;
1015 thp_pmd_to_pagemap_entry(&pme, pm, *pmd, offset, pmd_flags2);
1016 err = add_to_pagemap(addr, &pme, pm);
1017 if (err)
1018 break;
1019 }
1020 spin_unlock(ptl);
1021 return err;
1022 }
1023
1024 if (pmd_trans_unstable(pmd))
1025 return 0;
1026 for (; addr != end; addr += PAGE_SIZE) {
1027 int flags2;
1028
1029 /* check to see if we've left 'vma' behind
1030 * and need a new, higher one */
1031 if (vma && (addr >= vma->vm_end)) {
1032 vma = find_vma(walk->mm, addr);
1033 if (vma && (vma->vm_flags & VM_SOFTDIRTY))
1034 flags2 = __PM_SOFT_DIRTY;
1035 else
1036 flags2 = 0;
1037 pme = make_pme(PM_NOT_PRESENT(pm->v2) | PM_STATUS2(pm->v2, flags2));
1038 }
1039
1040 /* check that 'vma' actually covers this address,
1041 * and that it isn't a huge page vma */
1042 if (vma && (vma->vm_start <= addr) &&
1043 !is_vm_hugetlb_page(vma)) {
1044 pte = pte_offset_map(pmd, addr);
1045 pte_to_pagemap_entry(&pme, pm, vma, addr, *pte);
1046 /* unmap before userspace copy */
1047 pte_unmap(pte);
1048 }
1049 err = add_to_pagemap(addr, &pme, pm);
1050 if (err)
1051 return err;
1052 }
1053
1054 cond_resched();
1055
1056 return err;
1057}
1058
1059#ifdef CONFIG_HUGETLB_PAGE
1060static void huge_pte_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm,
1061 pte_t pte, int offset, int flags2)
1062{
1063 if (pte_present(pte))
1064 *pme = make_pme(PM_PFRAME(pte_pfn(pte) + offset) |
1065 PM_STATUS2(pm->v2, flags2) |
1066 PM_PRESENT);
1067 else
1068 *pme = make_pme(PM_NOT_PRESENT(pm->v2) |
1069 PM_STATUS2(pm->v2, flags2));
1070}
1071
1072/* This function walks within one hugetlb entry in the single call */
1073static int pagemap_hugetlb_range(pte_t *pte, unsigned long hmask,
1074 unsigned long addr, unsigned long end,
1075 struct mm_walk *walk)
1076{
1077 struct pagemapread *pm = walk->private;
1078 struct vm_area_struct *vma;
1079 int err = 0;
1080 int flags2;
1081 pagemap_entry_t pme;
1082
1083 vma = find_vma(walk->mm, addr);
1084 WARN_ON_ONCE(!vma);
1085
1086 if (vma && (vma->vm_flags & VM_SOFTDIRTY))
1087 flags2 = __PM_SOFT_DIRTY;
1088 else
1089 flags2 = 0;
1090
1091 for (; addr != end; addr += PAGE_SIZE) {
1092 int offset = (addr & ~hmask) >> PAGE_SHIFT;
1093 huge_pte_to_pagemap_entry(&pme, pm, *pte, offset, flags2);
1094 err = add_to_pagemap(addr, &pme, pm);
1095 if (err)
1096 return err;
1097 }
1098
1099 cond_resched();
1100
1101 return err;
1102}
1103#endif /* HUGETLB_PAGE */
1104
1105/*
1106 * /proc/pid/pagemap - an array mapping virtual pages to pfns
1107 *
1108 * For each page in the address space, this file contains one 64-bit entry
1109 * consisting of the following:
1110 *
1111 * Bits 0-54 page frame number (PFN) if present
1112 * Bits 0-4 swap type if swapped
1113 * Bits 5-54 swap offset if swapped
1114 * Bits 55-60 page shift (page size = 1<<page shift)
1115 * Bit 61 page is file-page or shared-anon
1116 * Bit 62 page swapped
1117 * Bit 63 page present
1118 *
1119 * If the page is not present but in swap, then the PFN contains an
1120 * encoding of the swap file number and the page's offset into the
1121 * swap. Unmapped pages return a null PFN. This allows determining
1122 * precisely which pages are mapped (or in swap) and comparing mapped
1123 * pages between processes.
1124 *
1125 * Efficient users of this interface will use /proc/pid/maps to
1126 * determine which areas of memory are actually mapped and llseek to
1127 * skip over unmapped regions.
1128 */
1129static ssize_t pagemap_read(struct file *file, char __user *buf,
1130 size_t count, loff_t *ppos)
1131{
1132 struct task_struct *task = get_proc_task(file_inode(file));
1133 struct mm_struct *mm;
1134 struct pagemapread pm;
1135 int ret = -ESRCH;
1136 struct mm_walk pagemap_walk = {};
1137 unsigned long src;
1138 unsigned long svpfn;
1139 unsigned long start_vaddr;
1140 unsigned long end_vaddr;
1141 int copied = 0;
1142
1143 if (!task)
1144 goto out;
1145
1146 ret = -EINVAL;
1147 /* file position must be aligned */
1148 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
1149 goto out_task;
1150
1151 ret = 0;
1152 if (!count)
1153 goto out_task;
1154
1155 pm.v2 = soft_dirty_cleared;
1156 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
1157 pm.buffer = kmalloc(pm.len * PM_ENTRY_BYTES, GFP_TEMPORARY);
1158 ret = -ENOMEM;
1159 if (!pm.buffer)
1160 goto out_task;
1161
1162 mm = mm_access(task, PTRACE_MODE_READ);
1163 ret = PTR_ERR(mm);
1164 if (!mm || IS_ERR(mm))
1165 goto out_free;
1166
1167 pagemap_walk.pmd_entry = pagemap_pte_range;
1168 pagemap_walk.pte_hole = pagemap_pte_hole;
1169#ifdef CONFIG_HUGETLB_PAGE
1170 pagemap_walk.hugetlb_entry = pagemap_hugetlb_range;
1171#endif
1172 pagemap_walk.mm = mm;
1173 pagemap_walk.private = ±
1174
1175 src = *ppos;
1176 svpfn = src / PM_ENTRY_BYTES;
1177 start_vaddr = svpfn << PAGE_SHIFT;
1178 end_vaddr = TASK_SIZE_OF(task);
1179
1180 /* watch out for wraparound */
1181 if (svpfn > TASK_SIZE_OF(task) >> PAGE_SHIFT)
1182 start_vaddr = end_vaddr;
1183
1184 /*
1185 * The odds are that this will stop walking way
1186 * before end_vaddr, because the length of the
1187 * user buffer is tracked in "pm", and the walk
1188 * will stop when we hit the end of the buffer.
1189 */
1190 ret = 0;
1191 while (count && (start_vaddr < end_vaddr)) {
1192 int len;
1193 unsigned long end;
1194
1195 pm.pos = 0;
1196 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
1197 /* overflow ? */
1198 if (end < start_vaddr || end > end_vaddr)
1199 end = end_vaddr;
1200 down_read(&mm->mmap_sem);
1201 ret = walk_page_range(start_vaddr, end, &pagemap_walk);
1202 up_read(&mm->mmap_sem);
1203 start_vaddr = end;
1204
1205 len = min(count, PM_ENTRY_BYTES * pm.pos);
1206 if (copy_to_user(buf, pm.buffer, len)) {
1207 ret = -EFAULT;
1208 goto out_mm;
1209 }
1210 copied += len;
1211 buf += len;
1212 count -= len;
1213 }
1214 *ppos += copied;
1215 if (!ret || ret == PM_END_OF_BUFFER)
1216 ret = copied;
1217
1218out_mm:
1219 mmput(mm);
1220out_free:
1221 kfree(pm.buffer);
1222out_task:
1223 put_task_struct(task);
1224out:
1225 return ret;
1226}
1227
1228static int pagemap_open(struct inode *inode, struct file *file)
1229{
1230 pr_warn_once("Bits 55-60 of /proc/PID/pagemap entries are about "
1231 "to stop being page-shift some time soon. See the "
1232 "linux/Documentation/vm/pagemap.txt for details.\n");
1233 return 0;
1234}
1235
1236const struct file_operations proc_pagemap_operations = {
1237 .llseek = mem_lseek, /* borrow this */
1238 .read = pagemap_read,
1239 .open = pagemap_open,
1240};
1241#endif /* CONFIG_PROC_PAGE_MONITOR */
1242
1243#ifdef CONFIG_NUMA
1244
1245struct numa_maps {
1246 struct vm_area_struct *vma;
1247 unsigned long pages;
1248 unsigned long anon;
1249 unsigned long active;
1250 unsigned long writeback;
1251 unsigned long mapcount_max;
1252 unsigned long dirty;
1253 unsigned long swapcache;
1254 unsigned long node[MAX_NUMNODES];
1255};
1256
1257struct numa_maps_private {
1258 struct proc_maps_private proc_maps;
1259 struct numa_maps md;
1260};
1261
1262static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
1263 unsigned long nr_pages)
1264{
1265 int count = page_mapcount(page);
1266
1267 md->pages += nr_pages;
1268 if (pte_dirty || PageDirty(page))
1269 md->dirty += nr_pages;
1270
1271 if (PageSwapCache(page))
1272 md->swapcache += nr_pages;
1273
1274 if (PageActive(page) || PageUnevictable(page))
1275 md->active += nr_pages;
1276
1277 if (PageWriteback(page))
1278 md->writeback += nr_pages;
1279
1280 if (PageAnon(page))
1281 md->anon += nr_pages;
1282
1283 if (count > md->mapcount_max)
1284 md->mapcount_max = count;
1285
1286 md->node[page_to_nid(page)] += nr_pages;
1287}
1288
1289static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
1290 unsigned long addr)
1291{
1292 struct page *page;
1293 int nid;
1294
1295 if (!pte_present(pte))
1296 return NULL;
1297
1298 page = vm_normal_page(vma, addr, pte);
1299 if (!page)
1300 return NULL;
1301
1302 if (PageReserved(page))
1303 return NULL;
1304
1305 nid = page_to_nid(page);
1306 if (!node_isset(nid, node_states[N_MEMORY]))
1307 return NULL;
1308
1309 return page;
1310}
1311
1312static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
1313 unsigned long end, struct mm_walk *walk)
1314{
1315 struct numa_maps *md;
1316 spinlock_t *ptl;
1317 pte_t *orig_pte;
1318 pte_t *pte;
1319
1320 md = walk->private;
1321
1322 if (pmd_trans_huge_lock(pmd, md->vma, &ptl) == 1) {
1323 pte_t huge_pte = *(pte_t *)pmd;
1324 struct page *page;
1325
1326 page = can_gather_numa_stats(huge_pte, md->vma, addr);
1327 if (page)
1328 gather_stats(page, md, pte_dirty(huge_pte),
1329 HPAGE_PMD_SIZE/PAGE_SIZE);
1330 spin_unlock(ptl);
1331 return 0;
1332 }
1333
1334 if (pmd_trans_unstable(pmd))
1335 return 0;
1336 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
1337 do {
1338 struct page *page = can_gather_numa_stats(*pte, md->vma, addr);
1339 if (!page)
1340 continue;
1341 gather_stats(page, md, pte_dirty(*pte), 1);
1342
1343 } while (pte++, addr += PAGE_SIZE, addr != end);
1344 pte_unmap_unlock(orig_pte, ptl);
1345 return 0;
1346}
1347#ifdef CONFIG_HUGETLB_PAGE
1348static int gather_hugetbl_stats(pte_t *pte, unsigned long hmask,
1349 unsigned long addr, unsigned long end, struct mm_walk *walk)
1350{
1351 struct numa_maps *md;
1352 struct page *page;
1353
1354 if (!pte_present(*pte))
1355 return 0;
1356
1357 page = pte_page(*pte);
1358 if (!page)
1359 return 0;
1360
1361 md = walk->private;
1362 gather_stats(page, md, pte_dirty(*pte), 1);
1363 return 0;
1364}
1365
1366#else
1367static int gather_hugetbl_stats(pte_t *pte, unsigned long hmask,
1368 unsigned long addr, unsigned long end, struct mm_walk *walk)
1369{
1370 return 0;
1371}
1372#endif
1373
1374/*
1375 * Display pages allocated per node and memory policy via /proc.
1376 */
1377static int show_numa_map(struct seq_file *m, void *v, int is_pid)
1378{
1379 struct numa_maps_private *numa_priv = m->private;
1380 struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
1381 struct vm_area_struct *vma = v;
1382 struct numa_maps *md = &numa_priv->md;
1383 struct file *file = vma->vm_file;
1384 struct task_struct *task = proc_priv->task;
1385 struct mm_struct *mm = vma->vm_mm;
1386 struct mm_walk walk = {};
1387 struct mempolicy *pol;
1388 char buffer[64];
1389 int nid;
1390
1391 if (!mm)
1392 return 0;
1393
1394 /* Ensure we start with an empty set of numa_maps statistics. */
1395 memset(md, 0, sizeof(*md));
1396
1397 md->vma = vma;
1398
1399 walk.hugetlb_entry = gather_hugetbl_stats;
1400 walk.pmd_entry = gather_pte_stats;
1401 walk.private = md;
1402 walk.mm = mm;
1403
1404 pol = get_vma_policy(task, vma, vma->vm_start);
1405 mpol_to_str(buffer, sizeof(buffer), pol);
1406 mpol_cond_put(pol);
1407
1408 seq_printf(m, "%08lx %s", vma->vm_start, buffer);
1409
1410 if (file) {
1411 seq_printf(m, " file=");
1412 seq_path(m, &file->f_path, "\n\t= ");
1413 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1414 seq_printf(m, " heap");
1415 } else {
1416 pid_t tid = vm_is_stack(task, vma, is_pid);
1417 if (tid != 0) {
1418 /*
1419 * Thread stack in /proc/PID/task/TID/maps or
1420 * the main process stack.
1421 */
1422 if (!is_pid || (vma->vm_start <= mm->start_stack &&
1423 vma->vm_end >= mm->start_stack))
1424 seq_printf(m, " stack");
1425 else
1426 seq_printf(m, " stack:%d", tid);
1427 }
1428 }
1429
1430 if (is_vm_hugetlb_page(vma))
1431 seq_printf(m, " huge");
1432
1433 walk_page_range(vma->vm_start, vma->vm_end, &walk);
1434
1435 if (!md->pages)
1436 goto out;
1437
1438 if (md->anon)
1439 seq_printf(m, " anon=%lu", md->anon);
1440
1441 if (md->dirty)
1442 seq_printf(m, " dirty=%lu", md->dirty);
1443
1444 if (md->pages != md->anon && md->pages != md->dirty)
1445 seq_printf(m, " mapped=%lu", md->pages);
1446
1447 if (md->mapcount_max > 1)
1448 seq_printf(m, " mapmax=%lu", md->mapcount_max);
1449
1450 if (md->swapcache)
1451 seq_printf(m, " swapcache=%lu", md->swapcache);
1452
1453 if (md->active < md->pages && !is_vm_hugetlb_page(vma))
1454 seq_printf(m, " active=%lu", md->active);
1455
1456 if (md->writeback)
1457 seq_printf(m, " writeback=%lu", md->writeback);
1458
1459 for_each_node_state(nid, N_MEMORY)
1460 if (md->node[nid])
1461 seq_printf(m, " N%d=%lu", nid, md->node[nid]);
1462out:
1463 seq_putc(m, '\n');
1464
1465 if (m->count < m->size)
1466 m->version = (vma != proc_priv->tail_vma) ? vma->vm_start : 0;
1467 return 0;
1468}
1469
1470static int show_pid_numa_map(struct seq_file *m, void *v)
1471{
1472 return show_numa_map(m, v, 1);
1473}
1474
1475static int show_tid_numa_map(struct seq_file *m, void *v)
1476{
1477 return show_numa_map(m, v, 0);
1478}
1479
1480static const struct seq_operations proc_pid_numa_maps_op = {
1481 .start = m_start,
1482 .next = m_next,
1483 .stop = m_stop,
1484 .show = show_pid_numa_map,
1485};
1486
1487static const struct seq_operations proc_tid_numa_maps_op = {
1488 .start = m_start,
1489 .next = m_next,
1490 .stop = m_stop,
1491 .show = show_tid_numa_map,
1492};
1493
1494static int numa_maps_open(struct inode *inode, struct file *file,
1495 const struct seq_operations *ops)
1496{
1497 struct numa_maps_private *priv;
1498 int ret = -ENOMEM;
1499 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1500 if (priv) {
1501 priv->proc_maps.pid = proc_pid(inode);
1502 ret = seq_open(file, ops);
1503 if (!ret) {
1504 struct seq_file *m = file->private_data;
1505 m->private = priv;
1506 } else {
1507 kfree(priv);
1508 }
1509 }
1510 return ret;
1511}
1512
1513static int pid_numa_maps_open(struct inode *inode, struct file *file)
1514{
1515 return numa_maps_open(inode, file, &proc_pid_numa_maps_op);
1516}
1517
1518static int tid_numa_maps_open(struct inode *inode, struct file *file)
1519{
1520 return numa_maps_open(inode, file, &proc_tid_numa_maps_op);
1521}
1522
1523const struct file_operations proc_pid_numa_maps_operations = {
1524 .open = pid_numa_maps_open,
1525 .read = seq_read,
1526 .llseek = seq_lseek,
1527 .release = seq_release_private,
1528};
1529
1530const struct file_operations proc_tid_numa_maps_operations = {
1531 .open = tid_numa_maps_open,
1532 .read = seq_read,
1533 .llseek = seq_lseek,
1534 .release = seq_release_private,
1535};
1536#endif /* CONFIG_NUMA */