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