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1#include <linux/mm.h>
2#include <linux/vmacache.h>
3#include <linux/hugetlb.h>
4#include <linux/huge_mm.h>
5#include <linux/mount.h>
6#include <linux/seq_file.h>
7#include <linux/highmem.h>
8#include <linux/ptrace.h>
9#include <linux/slab.h>
10#include <linux/pagemap.h>
11#include <linux/mempolicy.h>
12#include <linux/rmap.h>
13#include <linux/swap.h>
14#include <linux/swapops.h>
15#include <linux/mmu_notifier.h>
16#include <linux/page_idle.h>
17#include <linux/shmem_fs.h>
18
19#include <asm/elf.h>
20#include <asm/uaccess.h>
21#include <asm/tlbflush.h>
22#include "internal.h"
23
24void task_mem(struct seq_file *m, struct mm_struct *mm)
25{
26 unsigned long text, lib, swap, ptes, pmds, anon, file, shmem;
27 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
28
29 anon = get_mm_counter(mm, MM_ANONPAGES);
30 file = get_mm_counter(mm, MM_FILEPAGES);
31 shmem = get_mm_counter(mm, MM_SHMEMPAGES);
32
33 /*
34 * Note: to minimize their overhead, mm maintains hiwater_vm and
35 * hiwater_rss only when about to *lower* total_vm or rss. Any
36 * collector of these hiwater stats must therefore get total_vm
37 * and rss too, which will usually be the higher. Barriers? not
38 * worth the effort, such snapshots can always be inconsistent.
39 */
40 hiwater_vm = total_vm = mm->total_vm;
41 if (hiwater_vm < mm->hiwater_vm)
42 hiwater_vm = mm->hiwater_vm;
43 hiwater_rss = total_rss = anon + file + shmem;
44 if (hiwater_rss < mm->hiwater_rss)
45 hiwater_rss = mm->hiwater_rss;
46
47 text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10;
48 lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text;
49 swap = get_mm_counter(mm, MM_SWAPENTS);
50 ptes = PTRS_PER_PTE * sizeof(pte_t) * atomic_long_read(&mm->nr_ptes);
51 pmds = PTRS_PER_PMD * sizeof(pmd_t) * mm_nr_pmds(mm);
52 seq_printf(m,
53 "VmPeak:\t%8lu kB\n"
54 "VmSize:\t%8lu kB\n"
55 "VmLck:\t%8lu kB\n"
56 "VmPin:\t%8lu kB\n"
57 "VmHWM:\t%8lu kB\n"
58 "VmRSS:\t%8lu kB\n"
59 "RssAnon:\t%8lu kB\n"
60 "RssFile:\t%8lu kB\n"
61 "RssShmem:\t%8lu kB\n"
62 "VmData:\t%8lu kB\n"
63 "VmStk:\t%8lu kB\n"
64 "VmExe:\t%8lu kB\n"
65 "VmLib:\t%8lu kB\n"
66 "VmPTE:\t%8lu kB\n"
67 "VmPMD:\t%8lu kB\n"
68 "VmSwap:\t%8lu kB\n",
69 hiwater_vm << (PAGE_SHIFT-10),
70 total_vm << (PAGE_SHIFT-10),
71 mm->locked_vm << (PAGE_SHIFT-10),
72 mm->pinned_vm << (PAGE_SHIFT-10),
73 hiwater_rss << (PAGE_SHIFT-10),
74 total_rss << (PAGE_SHIFT-10),
75 anon << (PAGE_SHIFT-10),
76 file << (PAGE_SHIFT-10),
77 shmem << (PAGE_SHIFT-10),
78 mm->data_vm << (PAGE_SHIFT-10),
79 mm->stack_vm << (PAGE_SHIFT-10), text, lib,
80 ptes >> 10,
81 pmds >> 10,
82 swap << (PAGE_SHIFT-10));
83 hugetlb_report_usage(m, mm);
84}
85
86unsigned long task_vsize(struct mm_struct *mm)
87{
88 return PAGE_SIZE * mm->total_vm;
89}
90
91unsigned long task_statm(struct mm_struct *mm,
92 unsigned long *shared, unsigned long *text,
93 unsigned long *data, unsigned long *resident)
94{
95 *shared = get_mm_counter(mm, MM_FILEPAGES) +
96 get_mm_counter(mm, MM_SHMEMPAGES);
97 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
98 >> PAGE_SHIFT;
99 *data = mm->data_vm + mm->stack_vm;
100 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
101 return mm->total_vm;
102}
103
104#ifdef CONFIG_NUMA
105/*
106 * Save get_task_policy() for show_numa_map().
107 */
108static void hold_task_mempolicy(struct proc_maps_private *priv)
109{
110 struct task_struct *task = priv->task;
111
112 task_lock(task);
113 priv->task_mempolicy = get_task_policy(task);
114 mpol_get(priv->task_mempolicy);
115 task_unlock(task);
116}
117static void release_task_mempolicy(struct proc_maps_private *priv)
118{
119 mpol_put(priv->task_mempolicy);
120}
121#else
122static void hold_task_mempolicy(struct proc_maps_private *priv)
123{
124}
125static void release_task_mempolicy(struct proc_maps_private *priv)
126{
127}
128#endif
129
130static void vma_stop(struct proc_maps_private *priv)
131{
132 struct mm_struct *mm = priv->mm;
133
134 release_task_mempolicy(priv);
135 up_read(&mm->mmap_sem);
136 mmput(mm);
137}
138
139static struct vm_area_struct *
140m_next_vma(struct proc_maps_private *priv, struct vm_area_struct *vma)
141{
142 if (vma == priv->tail_vma)
143 return NULL;
144 return vma->vm_next ?: priv->tail_vma;
145}
146
147static void m_cache_vma(struct seq_file *m, struct vm_area_struct *vma)
148{
149 if (m->count < m->size) /* vma is copied successfully */
150 m->version = m_next_vma(m->private, vma) ? vma->vm_start : -1UL;
151}
152
153static void *m_start(struct seq_file *m, loff_t *ppos)
154{
155 struct proc_maps_private *priv = m->private;
156 unsigned long last_addr = m->version;
157 struct mm_struct *mm;
158 struct vm_area_struct *vma;
159 unsigned int pos = *ppos;
160
161 /* See m_cache_vma(). Zero at the start or after lseek. */
162 if (last_addr == -1UL)
163 return NULL;
164
165 priv->task = get_proc_task(priv->inode);
166 if (!priv->task)
167 return ERR_PTR(-ESRCH);
168
169 mm = priv->mm;
170 if (!mm || !atomic_inc_not_zero(&mm->mm_users))
171 return NULL;
172
173 down_read(&mm->mmap_sem);
174 hold_task_mempolicy(priv);
175 priv->tail_vma = get_gate_vma(mm);
176
177 if (last_addr) {
178 vma = find_vma(mm, last_addr);
179 if (vma && (vma = m_next_vma(priv, vma)))
180 return vma;
181 }
182
183 m->version = 0;
184 if (pos < mm->map_count) {
185 for (vma = mm->mmap; pos; pos--) {
186 m->version = vma->vm_start;
187 vma = vma->vm_next;
188 }
189 return vma;
190 }
191
192 /* we do not bother to update m->version in this case */
193 if (pos == mm->map_count && priv->tail_vma)
194 return priv->tail_vma;
195
196 vma_stop(priv);
197 return NULL;
198}
199
200static void *m_next(struct seq_file *m, void *v, loff_t *pos)
201{
202 struct proc_maps_private *priv = m->private;
203 struct vm_area_struct *next;
204
205 (*pos)++;
206 next = m_next_vma(priv, v);
207 if (!next)
208 vma_stop(priv);
209 return next;
210}
211
212static void m_stop(struct seq_file *m, void *v)
213{
214 struct proc_maps_private *priv = m->private;
215
216 if (!IS_ERR_OR_NULL(v))
217 vma_stop(priv);
218 if (priv->task) {
219 put_task_struct(priv->task);
220 priv->task = NULL;
221 }
222}
223
224static int proc_maps_open(struct inode *inode, struct file *file,
225 const struct seq_operations *ops, int psize)
226{
227 struct proc_maps_private *priv = __seq_open_private(file, ops, psize);
228
229 if (!priv)
230 return -ENOMEM;
231
232 priv->inode = inode;
233 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
234 if (IS_ERR(priv->mm)) {
235 int err = PTR_ERR(priv->mm);
236
237 seq_release_private(inode, file);
238 return err;
239 }
240
241 return 0;
242}
243
244static int proc_map_release(struct inode *inode, struct file *file)
245{
246 struct seq_file *seq = file->private_data;
247 struct proc_maps_private *priv = seq->private;
248
249 if (priv->mm)
250 mmdrop(priv->mm);
251
252 return seq_release_private(inode, file);
253}
254
255static int do_maps_open(struct inode *inode, struct file *file,
256 const struct seq_operations *ops)
257{
258 return proc_maps_open(inode, file, ops,
259 sizeof(struct proc_maps_private));
260}
261
262/*
263 * Indicate if the VMA is a stack for the given task; for
264 * /proc/PID/maps that is the stack of the main task.
265 */
266static int is_stack(struct proc_maps_private *priv,
267 struct vm_area_struct *vma, int is_pid)
268{
269 int stack = 0;
270
271 if (is_pid) {
272 stack = vma->vm_start <= vma->vm_mm->start_stack &&
273 vma->vm_end >= vma->vm_mm->start_stack;
274 } else {
275 struct inode *inode = priv->inode;
276 struct task_struct *task;
277
278 rcu_read_lock();
279 task = pid_task(proc_pid(inode), PIDTYPE_PID);
280 if (task)
281 stack = vma_is_stack_for_task(vma, task);
282 rcu_read_unlock();
283 }
284 return stack;
285}
286
287static void
288show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid)
289{
290 struct mm_struct *mm = vma->vm_mm;
291 struct file *file = vma->vm_file;
292 struct proc_maps_private *priv = m->private;
293 vm_flags_t flags = vma->vm_flags;
294 unsigned long ino = 0;
295 unsigned long long pgoff = 0;
296 unsigned long start, end;
297 dev_t dev = 0;
298 const char *name = NULL;
299
300 if (file) {
301 struct inode *inode = file_inode(vma->vm_file);
302 dev = inode->i_sb->s_dev;
303 ino = inode->i_ino;
304 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
305 }
306
307 /* We don't show the stack guard page in /proc/maps */
308 start = vma->vm_start;
309 if (stack_guard_page_start(vma, start))
310 start += PAGE_SIZE;
311 end = vma->vm_end;
312 if (stack_guard_page_end(vma, end))
313 end -= PAGE_SIZE;
314
315 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
316 seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu ",
317 start,
318 end,
319 flags & VM_READ ? 'r' : '-',
320 flags & VM_WRITE ? 'w' : '-',
321 flags & VM_EXEC ? 'x' : '-',
322 flags & VM_MAYSHARE ? 's' : 'p',
323 pgoff,
324 MAJOR(dev), MINOR(dev), ino);
325
326 /*
327 * Print the dentry name for named mappings, and a
328 * special [heap] marker for the heap:
329 */
330 if (file) {
331 seq_pad(m, ' ');
332 seq_file_path(m, file, "\n");
333 goto done;
334 }
335
336 if (vma->vm_ops && vma->vm_ops->name) {
337 name = vma->vm_ops->name(vma);
338 if (name)
339 goto done;
340 }
341
342 name = arch_vma_name(vma);
343 if (!name) {
344 if (!mm) {
345 name = "[vdso]";
346 goto done;
347 }
348
349 if (vma->vm_start <= mm->brk &&
350 vma->vm_end >= mm->start_brk) {
351 name = "[heap]";
352 goto done;
353 }
354
355 if (is_stack(priv, vma, is_pid))
356 name = "[stack]";
357 }
358
359done:
360 if (name) {
361 seq_pad(m, ' ');
362 seq_puts(m, name);
363 }
364 seq_putc(m, '\n');
365}
366
367static int show_map(struct seq_file *m, void *v, int is_pid)
368{
369 show_map_vma(m, v, is_pid);
370 m_cache_vma(m, v);
371 return 0;
372}
373
374static int show_pid_map(struct seq_file *m, void *v)
375{
376 return show_map(m, v, 1);
377}
378
379static int show_tid_map(struct seq_file *m, void *v)
380{
381 return show_map(m, v, 0);
382}
383
384static const struct seq_operations proc_pid_maps_op = {
385 .start = m_start,
386 .next = m_next,
387 .stop = m_stop,
388 .show = show_pid_map
389};
390
391static const struct seq_operations proc_tid_maps_op = {
392 .start = m_start,
393 .next = m_next,
394 .stop = m_stop,
395 .show = show_tid_map
396};
397
398static int pid_maps_open(struct inode *inode, struct file *file)
399{
400 return do_maps_open(inode, file, &proc_pid_maps_op);
401}
402
403static int tid_maps_open(struct inode *inode, struct file *file)
404{
405 return do_maps_open(inode, file, &proc_tid_maps_op);
406}
407
408const struct file_operations proc_pid_maps_operations = {
409 .open = pid_maps_open,
410 .read = seq_read,
411 .llseek = seq_lseek,
412 .release = proc_map_release,
413};
414
415const struct file_operations proc_tid_maps_operations = {
416 .open = tid_maps_open,
417 .read = seq_read,
418 .llseek = seq_lseek,
419 .release = proc_map_release,
420};
421
422/*
423 * Proportional Set Size(PSS): my share of RSS.
424 *
425 * PSS of a process is the count of pages it has in memory, where each
426 * page is divided by the number of processes sharing it. So if a
427 * process has 1000 pages all to itself, and 1000 shared with one other
428 * process, its PSS will be 1500.
429 *
430 * To keep (accumulated) division errors low, we adopt a 64bit
431 * fixed-point pss counter to minimize division errors. So (pss >>
432 * PSS_SHIFT) would be the real byte count.
433 *
434 * A shift of 12 before division means (assuming 4K page size):
435 * - 1M 3-user-pages add up to 8KB errors;
436 * - supports mapcount up to 2^24, or 16M;
437 * - supports PSS up to 2^52 bytes, or 4PB.
438 */
439#define PSS_SHIFT 12
440
441#ifdef CONFIG_PROC_PAGE_MONITOR
442struct mem_size_stats {
443 unsigned long resident;
444 unsigned long shared_clean;
445 unsigned long shared_dirty;
446 unsigned long private_clean;
447 unsigned long private_dirty;
448 unsigned long referenced;
449 unsigned long anonymous;
450 unsigned long anonymous_thp;
451 unsigned long swap;
452 unsigned long shared_hugetlb;
453 unsigned long private_hugetlb;
454 u64 pss;
455 u64 swap_pss;
456 bool check_shmem_swap;
457};
458
459static void smaps_account(struct mem_size_stats *mss, struct page *page,
460 bool compound, bool young, bool dirty)
461{
462 int i, nr = compound ? 1 << compound_order(page) : 1;
463 unsigned long size = nr * PAGE_SIZE;
464
465 if (PageAnon(page))
466 mss->anonymous += size;
467
468 mss->resident += size;
469 /* Accumulate the size in pages that have been accessed. */
470 if (young || page_is_young(page) || PageReferenced(page))
471 mss->referenced += size;
472
473 /*
474 * page_count(page) == 1 guarantees the page is mapped exactly once.
475 * If any subpage of the compound page mapped with PTE it would elevate
476 * page_count().
477 */
478 if (page_count(page) == 1) {
479 if (dirty || PageDirty(page))
480 mss->private_dirty += size;
481 else
482 mss->private_clean += size;
483 mss->pss += (u64)size << PSS_SHIFT;
484 return;
485 }
486
487 for (i = 0; i < nr; i++, page++) {
488 int mapcount = page_mapcount(page);
489
490 if (mapcount >= 2) {
491 if (dirty || PageDirty(page))
492 mss->shared_dirty += PAGE_SIZE;
493 else
494 mss->shared_clean += PAGE_SIZE;
495 mss->pss += (PAGE_SIZE << PSS_SHIFT) / mapcount;
496 } else {
497 if (dirty || PageDirty(page))
498 mss->private_dirty += PAGE_SIZE;
499 else
500 mss->private_clean += PAGE_SIZE;
501 mss->pss += PAGE_SIZE << PSS_SHIFT;
502 }
503 }
504}
505
506#ifdef CONFIG_SHMEM
507static int smaps_pte_hole(unsigned long addr, unsigned long end,
508 struct mm_walk *walk)
509{
510 struct mem_size_stats *mss = walk->private;
511
512 mss->swap += shmem_partial_swap_usage(
513 walk->vma->vm_file->f_mapping, addr, end);
514
515 return 0;
516}
517#endif
518
519static void smaps_pte_entry(pte_t *pte, unsigned long addr,
520 struct mm_walk *walk)
521{
522 struct mem_size_stats *mss = walk->private;
523 struct vm_area_struct *vma = walk->vma;
524 struct page *page = NULL;
525
526 if (pte_present(*pte)) {
527 page = vm_normal_page(vma, addr, *pte);
528 } else if (is_swap_pte(*pte)) {
529 swp_entry_t swpent = pte_to_swp_entry(*pte);
530
531 if (!non_swap_entry(swpent)) {
532 int mapcount;
533
534 mss->swap += PAGE_SIZE;
535 mapcount = swp_swapcount(swpent);
536 if (mapcount >= 2) {
537 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT;
538
539 do_div(pss_delta, mapcount);
540 mss->swap_pss += pss_delta;
541 } else {
542 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT;
543 }
544 } else if (is_migration_entry(swpent))
545 page = migration_entry_to_page(swpent);
546 } else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap
547 && pte_none(*pte))) {
548 page = find_get_entry(vma->vm_file->f_mapping,
549 linear_page_index(vma, addr));
550 if (!page)
551 return;
552
553 if (radix_tree_exceptional_entry(page))
554 mss->swap += PAGE_SIZE;
555 else
556 put_page(page);
557
558 return;
559 }
560
561 if (!page)
562 return;
563
564 smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte));
565}
566
567#ifdef CONFIG_TRANSPARENT_HUGEPAGE
568static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
569 struct mm_walk *walk)
570{
571 struct mem_size_stats *mss = walk->private;
572 struct vm_area_struct *vma = walk->vma;
573 struct page *page;
574
575 /* FOLL_DUMP will return -EFAULT on huge zero page */
576 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
577 if (IS_ERR_OR_NULL(page))
578 return;
579 mss->anonymous_thp += HPAGE_PMD_SIZE;
580 smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd));
581}
582#else
583static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
584 struct mm_walk *walk)
585{
586}
587#endif
588
589static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
590 struct mm_walk *walk)
591{
592 struct vm_area_struct *vma = walk->vma;
593 pte_t *pte;
594 spinlock_t *ptl;
595
596 ptl = pmd_trans_huge_lock(pmd, vma);
597 if (ptl) {
598 smaps_pmd_entry(pmd, addr, walk);
599 spin_unlock(ptl);
600 return 0;
601 }
602
603 if (pmd_trans_unstable(pmd))
604 return 0;
605 /*
606 * The mmap_sem held all the way back in m_start() is what
607 * keeps khugepaged out of here and from collapsing things
608 * in here.
609 */
610 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
611 for (; addr != end; pte++, addr += PAGE_SIZE)
612 smaps_pte_entry(pte, addr, walk);
613 pte_unmap_unlock(pte - 1, ptl);
614 cond_resched();
615 return 0;
616}
617
618static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
619{
620 /*
621 * Don't forget to update Documentation/ on changes.
622 */
623 static const char mnemonics[BITS_PER_LONG][2] = {
624 /*
625 * In case if we meet a flag we don't know about.
626 */
627 [0 ... (BITS_PER_LONG-1)] = "??",
628
629 [ilog2(VM_READ)] = "rd",
630 [ilog2(VM_WRITE)] = "wr",
631 [ilog2(VM_EXEC)] = "ex",
632 [ilog2(VM_SHARED)] = "sh",
633 [ilog2(VM_MAYREAD)] = "mr",
634 [ilog2(VM_MAYWRITE)] = "mw",
635 [ilog2(VM_MAYEXEC)] = "me",
636 [ilog2(VM_MAYSHARE)] = "ms",
637 [ilog2(VM_GROWSDOWN)] = "gd",
638 [ilog2(VM_PFNMAP)] = "pf",
639 [ilog2(VM_DENYWRITE)] = "dw",
640#ifdef CONFIG_X86_INTEL_MPX
641 [ilog2(VM_MPX)] = "mp",
642#endif
643 [ilog2(VM_LOCKED)] = "lo",
644 [ilog2(VM_IO)] = "io",
645 [ilog2(VM_SEQ_READ)] = "sr",
646 [ilog2(VM_RAND_READ)] = "rr",
647 [ilog2(VM_DONTCOPY)] = "dc",
648 [ilog2(VM_DONTEXPAND)] = "de",
649 [ilog2(VM_ACCOUNT)] = "ac",
650 [ilog2(VM_NORESERVE)] = "nr",
651 [ilog2(VM_HUGETLB)] = "ht",
652 [ilog2(VM_ARCH_1)] = "ar",
653 [ilog2(VM_DONTDUMP)] = "dd",
654#ifdef CONFIG_MEM_SOFT_DIRTY
655 [ilog2(VM_SOFTDIRTY)] = "sd",
656#endif
657 [ilog2(VM_MIXEDMAP)] = "mm",
658 [ilog2(VM_HUGEPAGE)] = "hg",
659 [ilog2(VM_NOHUGEPAGE)] = "nh",
660 [ilog2(VM_MERGEABLE)] = "mg",
661 [ilog2(VM_UFFD_MISSING)]= "um",
662 [ilog2(VM_UFFD_WP)] = "uw",
663#ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
664 /* These come out via ProtectionKey: */
665 [ilog2(VM_PKEY_BIT0)] = "",
666 [ilog2(VM_PKEY_BIT1)] = "",
667 [ilog2(VM_PKEY_BIT2)] = "",
668 [ilog2(VM_PKEY_BIT3)] = "",
669#endif
670 };
671 size_t i;
672
673 seq_puts(m, "VmFlags: ");
674 for (i = 0; i < BITS_PER_LONG; i++) {
675 if (!mnemonics[i][0])
676 continue;
677 if (vma->vm_flags & (1UL << i)) {
678 seq_printf(m, "%c%c ",
679 mnemonics[i][0], mnemonics[i][1]);
680 }
681 }
682 seq_putc(m, '\n');
683}
684
685#ifdef CONFIG_HUGETLB_PAGE
686static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,
687 unsigned long addr, unsigned long end,
688 struct mm_walk *walk)
689{
690 struct mem_size_stats *mss = walk->private;
691 struct vm_area_struct *vma = walk->vma;
692 struct page *page = NULL;
693
694 if (pte_present(*pte)) {
695 page = vm_normal_page(vma, addr, *pte);
696 } else if (is_swap_pte(*pte)) {
697 swp_entry_t swpent = pte_to_swp_entry(*pte);
698
699 if (is_migration_entry(swpent))
700 page = migration_entry_to_page(swpent);
701 }
702 if (page) {
703 int mapcount = page_mapcount(page);
704
705 if (mapcount >= 2)
706 mss->shared_hugetlb += huge_page_size(hstate_vma(vma));
707 else
708 mss->private_hugetlb += huge_page_size(hstate_vma(vma));
709 }
710 return 0;
711}
712#endif /* HUGETLB_PAGE */
713
714void __weak arch_show_smap(struct seq_file *m, struct vm_area_struct *vma)
715{
716}
717
718static int show_smap(struct seq_file *m, void *v, int is_pid)
719{
720 struct vm_area_struct *vma = v;
721 struct mem_size_stats mss;
722 struct mm_walk smaps_walk = {
723 .pmd_entry = smaps_pte_range,
724#ifdef CONFIG_HUGETLB_PAGE
725 .hugetlb_entry = smaps_hugetlb_range,
726#endif
727 .mm = vma->vm_mm,
728 .private = &mss,
729 };
730
731 memset(&mss, 0, sizeof mss);
732
733#ifdef CONFIG_SHMEM
734 if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) {
735 /*
736 * For shared or readonly shmem mappings we know that all
737 * swapped out pages belong to the shmem object, and we can
738 * obtain the swap value much more efficiently. For private
739 * writable mappings, we might have COW pages that are
740 * not affected by the parent swapped out pages of the shmem
741 * object, so we have to distinguish them during the page walk.
742 * Unless we know that the shmem object (or the part mapped by
743 * our VMA) has no swapped out pages at all.
744 */
745 unsigned long shmem_swapped = shmem_swap_usage(vma);
746
747 if (!shmem_swapped || (vma->vm_flags & VM_SHARED) ||
748 !(vma->vm_flags & VM_WRITE)) {
749 mss.swap = shmem_swapped;
750 } else {
751 mss.check_shmem_swap = true;
752 smaps_walk.pte_hole = smaps_pte_hole;
753 }
754 }
755#endif
756
757 /* mmap_sem is held in m_start */
758 walk_page_vma(vma, &smaps_walk);
759
760 show_map_vma(m, vma, is_pid);
761
762 seq_printf(m,
763 "Size: %8lu kB\n"
764 "Rss: %8lu kB\n"
765 "Pss: %8lu kB\n"
766 "Shared_Clean: %8lu kB\n"
767 "Shared_Dirty: %8lu kB\n"
768 "Private_Clean: %8lu kB\n"
769 "Private_Dirty: %8lu kB\n"
770 "Referenced: %8lu kB\n"
771 "Anonymous: %8lu kB\n"
772 "AnonHugePages: %8lu kB\n"
773 "Shared_Hugetlb: %8lu kB\n"
774 "Private_Hugetlb: %7lu kB\n"
775 "Swap: %8lu kB\n"
776 "SwapPss: %8lu kB\n"
777 "KernelPageSize: %8lu kB\n"
778 "MMUPageSize: %8lu kB\n"
779 "Locked: %8lu kB\n",
780 (vma->vm_end - vma->vm_start) >> 10,
781 mss.resident >> 10,
782 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)),
783 mss.shared_clean >> 10,
784 mss.shared_dirty >> 10,
785 mss.private_clean >> 10,
786 mss.private_dirty >> 10,
787 mss.referenced >> 10,
788 mss.anonymous >> 10,
789 mss.anonymous_thp >> 10,
790 mss.shared_hugetlb >> 10,
791 mss.private_hugetlb >> 10,
792 mss.swap >> 10,
793 (unsigned long)(mss.swap_pss >> (10 + PSS_SHIFT)),
794 vma_kernel_pagesize(vma) >> 10,
795 vma_mmu_pagesize(vma) >> 10,
796 (vma->vm_flags & VM_LOCKED) ?
797 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0);
798
799 arch_show_smap(m, vma);
800 show_smap_vma_flags(m, vma);
801 m_cache_vma(m, vma);
802 return 0;
803}
804
805static int show_pid_smap(struct seq_file *m, void *v)
806{
807 return show_smap(m, v, 1);
808}
809
810static int show_tid_smap(struct seq_file *m, void *v)
811{
812 return show_smap(m, v, 0);
813}
814
815static const struct seq_operations proc_pid_smaps_op = {
816 .start = m_start,
817 .next = m_next,
818 .stop = m_stop,
819 .show = show_pid_smap
820};
821
822static const struct seq_operations proc_tid_smaps_op = {
823 .start = m_start,
824 .next = m_next,
825 .stop = m_stop,
826 .show = show_tid_smap
827};
828
829static int pid_smaps_open(struct inode *inode, struct file *file)
830{
831 return do_maps_open(inode, file, &proc_pid_smaps_op);
832}
833
834static int tid_smaps_open(struct inode *inode, struct file *file)
835{
836 return do_maps_open(inode, file, &proc_tid_smaps_op);
837}
838
839const struct file_operations proc_pid_smaps_operations = {
840 .open = pid_smaps_open,
841 .read = seq_read,
842 .llseek = seq_lseek,
843 .release = proc_map_release,
844};
845
846const struct file_operations proc_tid_smaps_operations = {
847 .open = tid_smaps_open,
848 .read = seq_read,
849 .llseek = seq_lseek,
850 .release = proc_map_release,
851};
852
853enum clear_refs_types {
854 CLEAR_REFS_ALL = 1,
855 CLEAR_REFS_ANON,
856 CLEAR_REFS_MAPPED,
857 CLEAR_REFS_SOFT_DIRTY,
858 CLEAR_REFS_MM_HIWATER_RSS,
859 CLEAR_REFS_LAST,
860};
861
862struct clear_refs_private {
863 enum clear_refs_types type;
864};
865
866#ifdef CONFIG_MEM_SOFT_DIRTY
867static inline void clear_soft_dirty(struct vm_area_struct *vma,
868 unsigned long addr, pte_t *pte)
869{
870 /*
871 * The soft-dirty tracker uses #PF-s to catch writes
872 * to pages, so write-protect the pte as well. See the
873 * Documentation/vm/soft-dirty.txt for full description
874 * of how soft-dirty works.
875 */
876 pte_t ptent = *pte;
877
878 if (pte_present(ptent)) {
879 ptent = ptep_modify_prot_start(vma->vm_mm, addr, pte);
880 ptent = pte_wrprotect(ptent);
881 ptent = pte_clear_soft_dirty(ptent);
882 ptep_modify_prot_commit(vma->vm_mm, addr, pte, ptent);
883 } else if (is_swap_pte(ptent)) {
884 ptent = pte_swp_clear_soft_dirty(ptent);
885 set_pte_at(vma->vm_mm, addr, pte, ptent);
886 }
887}
888#else
889static inline void clear_soft_dirty(struct vm_area_struct *vma,
890 unsigned long addr, pte_t *pte)
891{
892}
893#endif
894
895#if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
896static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
897 unsigned long addr, pmd_t *pmdp)
898{
899 pmd_t pmd = pmdp_huge_get_and_clear(vma->vm_mm, addr, pmdp);
900
901 pmd = pmd_wrprotect(pmd);
902 pmd = pmd_clear_soft_dirty(pmd);
903
904 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
905}
906#else
907static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
908 unsigned long addr, pmd_t *pmdp)
909{
910}
911#endif
912
913static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
914 unsigned long end, struct mm_walk *walk)
915{
916 struct clear_refs_private *cp = walk->private;
917 struct vm_area_struct *vma = walk->vma;
918 pte_t *pte, ptent;
919 spinlock_t *ptl;
920 struct page *page;
921
922 ptl = pmd_trans_huge_lock(pmd, vma);
923 if (ptl) {
924 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
925 clear_soft_dirty_pmd(vma, addr, pmd);
926 goto out;
927 }
928
929 page = pmd_page(*pmd);
930
931 /* Clear accessed and referenced bits. */
932 pmdp_test_and_clear_young(vma, addr, pmd);
933 test_and_clear_page_young(page);
934 ClearPageReferenced(page);
935out:
936 spin_unlock(ptl);
937 return 0;
938 }
939
940 if (pmd_trans_unstable(pmd))
941 return 0;
942
943 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
944 for (; addr != end; pte++, addr += PAGE_SIZE) {
945 ptent = *pte;
946
947 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
948 clear_soft_dirty(vma, addr, pte);
949 continue;
950 }
951
952 if (!pte_present(ptent))
953 continue;
954
955 page = vm_normal_page(vma, addr, ptent);
956 if (!page)
957 continue;
958
959 /* Clear accessed and referenced bits. */
960 ptep_test_and_clear_young(vma, addr, pte);
961 test_and_clear_page_young(page);
962 ClearPageReferenced(page);
963 }
964 pte_unmap_unlock(pte - 1, ptl);
965 cond_resched();
966 return 0;
967}
968
969static int clear_refs_test_walk(unsigned long start, unsigned long end,
970 struct mm_walk *walk)
971{
972 struct clear_refs_private *cp = walk->private;
973 struct vm_area_struct *vma = walk->vma;
974
975 if (vma->vm_flags & VM_PFNMAP)
976 return 1;
977
978 /*
979 * Writing 1 to /proc/pid/clear_refs affects all pages.
980 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages.
981 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages.
982 * Writing 4 to /proc/pid/clear_refs affects all pages.
983 */
984 if (cp->type == CLEAR_REFS_ANON && vma->vm_file)
985 return 1;
986 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file)
987 return 1;
988 return 0;
989}
990
991static ssize_t clear_refs_write(struct file *file, const char __user *buf,
992 size_t count, loff_t *ppos)
993{
994 struct task_struct *task;
995 char buffer[PROC_NUMBUF];
996 struct mm_struct *mm;
997 struct vm_area_struct *vma;
998 enum clear_refs_types type;
999 int itype;
1000 int rv;
1001
1002 memset(buffer, 0, sizeof(buffer));
1003 if (count > sizeof(buffer) - 1)
1004 count = sizeof(buffer) - 1;
1005 if (copy_from_user(buffer, buf, count))
1006 return -EFAULT;
1007 rv = kstrtoint(strstrip(buffer), 10, &itype);
1008 if (rv < 0)
1009 return rv;
1010 type = (enum clear_refs_types)itype;
1011 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
1012 return -EINVAL;
1013
1014 task = get_proc_task(file_inode(file));
1015 if (!task)
1016 return -ESRCH;
1017 mm = get_task_mm(task);
1018 if (mm) {
1019 struct clear_refs_private cp = {
1020 .type = type,
1021 };
1022 struct mm_walk clear_refs_walk = {
1023 .pmd_entry = clear_refs_pte_range,
1024 .test_walk = clear_refs_test_walk,
1025 .mm = mm,
1026 .private = &cp,
1027 };
1028
1029 if (type == CLEAR_REFS_MM_HIWATER_RSS) {
1030 /*
1031 * Writing 5 to /proc/pid/clear_refs resets the peak
1032 * resident set size to this mm's current rss value.
1033 */
1034 down_write(&mm->mmap_sem);
1035 reset_mm_hiwater_rss(mm);
1036 up_write(&mm->mmap_sem);
1037 goto out_mm;
1038 }
1039
1040 down_read(&mm->mmap_sem);
1041 if (type == CLEAR_REFS_SOFT_DIRTY) {
1042 for (vma = mm->mmap; vma; vma = vma->vm_next) {
1043 if (!(vma->vm_flags & VM_SOFTDIRTY))
1044 continue;
1045 up_read(&mm->mmap_sem);
1046 down_write(&mm->mmap_sem);
1047 for (vma = mm->mmap; vma; vma = vma->vm_next) {
1048 vma->vm_flags &= ~VM_SOFTDIRTY;
1049 vma_set_page_prot(vma);
1050 }
1051 downgrade_write(&mm->mmap_sem);
1052 break;
1053 }
1054 mmu_notifier_invalidate_range_start(mm, 0, -1);
1055 }
1056 walk_page_range(0, ~0UL, &clear_refs_walk);
1057 if (type == CLEAR_REFS_SOFT_DIRTY)
1058 mmu_notifier_invalidate_range_end(mm, 0, -1);
1059 flush_tlb_mm(mm);
1060 up_read(&mm->mmap_sem);
1061out_mm:
1062 mmput(mm);
1063 }
1064 put_task_struct(task);
1065
1066 return count;
1067}
1068
1069const struct file_operations proc_clear_refs_operations = {
1070 .write = clear_refs_write,
1071 .llseek = noop_llseek,
1072};
1073
1074typedef struct {
1075 u64 pme;
1076} pagemap_entry_t;
1077
1078struct pagemapread {
1079 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */
1080 pagemap_entry_t *buffer;
1081 bool show_pfn;
1082};
1083
1084#define PAGEMAP_WALK_SIZE (PMD_SIZE)
1085#define PAGEMAP_WALK_MASK (PMD_MASK)
1086
1087#define PM_ENTRY_BYTES sizeof(pagemap_entry_t)
1088#define PM_PFRAME_BITS 55
1089#define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0)
1090#define PM_SOFT_DIRTY BIT_ULL(55)
1091#define PM_MMAP_EXCLUSIVE BIT_ULL(56)
1092#define PM_FILE BIT_ULL(61)
1093#define PM_SWAP BIT_ULL(62)
1094#define PM_PRESENT BIT_ULL(63)
1095
1096#define PM_END_OF_BUFFER 1
1097
1098static inline pagemap_entry_t make_pme(u64 frame, u64 flags)
1099{
1100 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags };
1101}
1102
1103static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme,
1104 struct pagemapread *pm)
1105{
1106 pm->buffer[pm->pos++] = *pme;
1107 if (pm->pos >= pm->len)
1108 return PM_END_OF_BUFFER;
1109 return 0;
1110}
1111
1112static int pagemap_pte_hole(unsigned long start, unsigned long end,
1113 struct mm_walk *walk)
1114{
1115 struct pagemapread *pm = walk->private;
1116 unsigned long addr = start;
1117 int err = 0;
1118
1119 while (addr < end) {
1120 struct vm_area_struct *vma = find_vma(walk->mm, addr);
1121 pagemap_entry_t pme = make_pme(0, 0);
1122 /* End of address space hole, which we mark as non-present. */
1123 unsigned long hole_end;
1124
1125 if (vma)
1126 hole_end = min(end, vma->vm_start);
1127 else
1128 hole_end = end;
1129
1130 for (; addr < hole_end; addr += PAGE_SIZE) {
1131 err = add_to_pagemap(addr, &pme, pm);
1132 if (err)
1133 goto out;
1134 }
1135
1136 if (!vma)
1137 break;
1138
1139 /* Addresses in the VMA. */
1140 if (vma->vm_flags & VM_SOFTDIRTY)
1141 pme = make_pme(0, PM_SOFT_DIRTY);
1142 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) {
1143 err = add_to_pagemap(addr, &pme, pm);
1144 if (err)
1145 goto out;
1146 }
1147 }
1148out:
1149 return err;
1150}
1151
1152static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm,
1153 struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1154{
1155 u64 frame = 0, flags = 0;
1156 struct page *page = NULL;
1157
1158 if (pte_present(pte)) {
1159 if (pm->show_pfn)
1160 frame = pte_pfn(pte);
1161 flags |= PM_PRESENT;
1162 page = vm_normal_page(vma, addr, pte);
1163 if (pte_soft_dirty(pte))
1164 flags |= PM_SOFT_DIRTY;
1165 } else if (is_swap_pte(pte)) {
1166 swp_entry_t entry;
1167 if (pte_swp_soft_dirty(pte))
1168 flags |= PM_SOFT_DIRTY;
1169 entry = pte_to_swp_entry(pte);
1170 frame = swp_type(entry) |
1171 (swp_offset(entry) << MAX_SWAPFILES_SHIFT);
1172 flags |= PM_SWAP;
1173 if (is_migration_entry(entry))
1174 page = migration_entry_to_page(entry);
1175 }
1176
1177 if (page && !PageAnon(page))
1178 flags |= PM_FILE;
1179 if (page && page_mapcount(page) == 1)
1180 flags |= PM_MMAP_EXCLUSIVE;
1181 if (vma->vm_flags & VM_SOFTDIRTY)
1182 flags |= PM_SOFT_DIRTY;
1183
1184 return make_pme(frame, flags);
1185}
1186
1187static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
1188 struct mm_walk *walk)
1189{
1190 struct vm_area_struct *vma = walk->vma;
1191 struct pagemapread *pm = walk->private;
1192 spinlock_t *ptl;
1193 pte_t *pte, *orig_pte;
1194 int err = 0;
1195
1196#ifdef CONFIG_TRANSPARENT_HUGEPAGE
1197 ptl = pmd_trans_huge_lock(pmdp, vma);
1198 if (ptl) {
1199 u64 flags = 0, frame = 0;
1200 pmd_t pmd = *pmdp;
1201
1202 if ((vma->vm_flags & VM_SOFTDIRTY) || pmd_soft_dirty(pmd))
1203 flags |= PM_SOFT_DIRTY;
1204
1205 /*
1206 * Currently pmd for thp is always present because thp
1207 * can not be swapped-out, migrated, or HWPOISONed
1208 * (split in such cases instead.)
1209 * This if-check is just to prepare for future implementation.
1210 */
1211 if (pmd_present(pmd)) {
1212 struct page *page = pmd_page(pmd);
1213
1214 if (page_mapcount(page) == 1)
1215 flags |= PM_MMAP_EXCLUSIVE;
1216
1217 flags |= PM_PRESENT;
1218 if (pm->show_pfn)
1219 frame = pmd_pfn(pmd) +
1220 ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1221 }
1222
1223 for (; addr != end; addr += PAGE_SIZE) {
1224 pagemap_entry_t pme = make_pme(frame, flags);
1225
1226 err = add_to_pagemap(addr, &pme, pm);
1227 if (err)
1228 break;
1229 if (pm->show_pfn && (flags & PM_PRESENT))
1230 frame++;
1231 }
1232 spin_unlock(ptl);
1233 return err;
1234 }
1235
1236 if (pmd_trans_unstable(pmdp))
1237 return 0;
1238#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1239
1240 /*
1241 * We can assume that @vma always points to a valid one and @end never
1242 * goes beyond vma->vm_end.
1243 */
1244 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl);
1245 for (; addr < end; pte++, addr += PAGE_SIZE) {
1246 pagemap_entry_t pme;
1247
1248 pme = pte_to_pagemap_entry(pm, vma, addr, *pte);
1249 err = add_to_pagemap(addr, &pme, pm);
1250 if (err)
1251 break;
1252 }
1253 pte_unmap_unlock(orig_pte, ptl);
1254
1255 cond_resched();
1256
1257 return err;
1258}
1259
1260#ifdef CONFIG_HUGETLB_PAGE
1261/* This function walks within one hugetlb entry in the single call */
1262static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask,
1263 unsigned long addr, unsigned long end,
1264 struct mm_walk *walk)
1265{
1266 struct pagemapread *pm = walk->private;
1267 struct vm_area_struct *vma = walk->vma;
1268 u64 flags = 0, frame = 0;
1269 int err = 0;
1270 pte_t pte;
1271
1272 if (vma->vm_flags & VM_SOFTDIRTY)
1273 flags |= PM_SOFT_DIRTY;
1274
1275 pte = huge_ptep_get(ptep);
1276 if (pte_present(pte)) {
1277 struct page *page = pte_page(pte);
1278
1279 if (!PageAnon(page))
1280 flags |= PM_FILE;
1281
1282 if (page_mapcount(page) == 1)
1283 flags |= PM_MMAP_EXCLUSIVE;
1284
1285 flags |= PM_PRESENT;
1286 if (pm->show_pfn)
1287 frame = pte_pfn(pte) +
1288 ((addr & ~hmask) >> PAGE_SHIFT);
1289 }
1290
1291 for (; addr != end; addr += PAGE_SIZE) {
1292 pagemap_entry_t pme = make_pme(frame, flags);
1293
1294 err = add_to_pagemap(addr, &pme, pm);
1295 if (err)
1296 return err;
1297 if (pm->show_pfn && (flags & PM_PRESENT))
1298 frame++;
1299 }
1300
1301 cond_resched();
1302
1303 return err;
1304}
1305#endif /* HUGETLB_PAGE */
1306
1307/*
1308 * /proc/pid/pagemap - an array mapping virtual pages to pfns
1309 *
1310 * For each page in the address space, this file contains one 64-bit entry
1311 * consisting of the following:
1312 *
1313 * Bits 0-54 page frame number (PFN) if present
1314 * Bits 0-4 swap type if swapped
1315 * Bits 5-54 swap offset if swapped
1316 * Bit 55 pte is soft-dirty (see Documentation/vm/soft-dirty.txt)
1317 * Bit 56 page exclusively mapped
1318 * Bits 57-60 zero
1319 * Bit 61 page is file-page or shared-anon
1320 * Bit 62 page swapped
1321 * Bit 63 page present
1322 *
1323 * If the page is not present but in swap, then the PFN contains an
1324 * encoding of the swap file number and the page's offset into the
1325 * swap. Unmapped pages return a null PFN. This allows determining
1326 * precisely which pages are mapped (or in swap) and comparing mapped
1327 * pages between processes.
1328 *
1329 * Efficient users of this interface will use /proc/pid/maps to
1330 * determine which areas of memory are actually mapped and llseek to
1331 * skip over unmapped regions.
1332 */
1333static ssize_t pagemap_read(struct file *file, char __user *buf,
1334 size_t count, loff_t *ppos)
1335{
1336 struct mm_struct *mm = file->private_data;
1337 struct pagemapread pm;
1338 struct mm_walk pagemap_walk = {};
1339 unsigned long src;
1340 unsigned long svpfn;
1341 unsigned long start_vaddr;
1342 unsigned long end_vaddr;
1343 int ret = 0, copied = 0;
1344
1345 if (!mm || !atomic_inc_not_zero(&mm->mm_users))
1346 goto out;
1347
1348 ret = -EINVAL;
1349 /* file position must be aligned */
1350 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
1351 goto out_mm;
1352
1353 ret = 0;
1354 if (!count)
1355 goto out_mm;
1356
1357 /* do not disclose physical addresses: attack vector */
1358 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN);
1359
1360 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
1361 pm.buffer = kmalloc(pm.len * PM_ENTRY_BYTES, GFP_TEMPORARY);
1362 ret = -ENOMEM;
1363 if (!pm.buffer)
1364 goto out_mm;
1365
1366 pagemap_walk.pmd_entry = pagemap_pmd_range;
1367 pagemap_walk.pte_hole = pagemap_pte_hole;
1368#ifdef CONFIG_HUGETLB_PAGE
1369 pagemap_walk.hugetlb_entry = pagemap_hugetlb_range;
1370#endif
1371 pagemap_walk.mm = mm;
1372 pagemap_walk.private = ±
1373
1374 src = *ppos;
1375 svpfn = src / PM_ENTRY_BYTES;
1376 start_vaddr = svpfn << PAGE_SHIFT;
1377 end_vaddr = mm->task_size;
1378
1379 /* watch out for wraparound */
1380 if (svpfn > mm->task_size >> PAGE_SHIFT)
1381 start_vaddr = end_vaddr;
1382
1383 /*
1384 * The odds are that this will stop walking way
1385 * before end_vaddr, because the length of the
1386 * user buffer is tracked in "pm", and the walk
1387 * will stop when we hit the end of the buffer.
1388 */
1389 ret = 0;
1390 while (count && (start_vaddr < end_vaddr)) {
1391 int len;
1392 unsigned long end;
1393
1394 pm.pos = 0;
1395 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
1396 /* overflow ? */
1397 if (end < start_vaddr || end > end_vaddr)
1398 end = end_vaddr;
1399 down_read(&mm->mmap_sem);
1400 ret = walk_page_range(start_vaddr, end, &pagemap_walk);
1401 up_read(&mm->mmap_sem);
1402 start_vaddr = end;
1403
1404 len = min(count, PM_ENTRY_BYTES * pm.pos);
1405 if (copy_to_user(buf, pm.buffer, len)) {
1406 ret = -EFAULT;
1407 goto out_free;
1408 }
1409 copied += len;
1410 buf += len;
1411 count -= len;
1412 }
1413 *ppos += copied;
1414 if (!ret || ret == PM_END_OF_BUFFER)
1415 ret = copied;
1416
1417out_free:
1418 kfree(pm.buffer);
1419out_mm:
1420 mmput(mm);
1421out:
1422 return ret;
1423}
1424
1425static int pagemap_open(struct inode *inode, struct file *file)
1426{
1427 struct mm_struct *mm;
1428
1429 mm = proc_mem_open(inode, PTRACE_MODE_READ);
1430 if (IS_ERR(mm))
1431 return PTR_ERR(mm);
1432 file->private_data = mm;
1433 return 0;
1434}
1435
1436static int pagemap_release(struct inode *inode, struct file *file)
1437{
1438 struct mm_struct *mm = file->private_data;
1439
1440 if (mm)
1441 mmdrop(mm);
1442 return 0;
1443}
1444
1445const struct file_operations proc_pagemap_operations = {
1446 .llseek = mem_lseek, /* borrow this */
1447 .read = pagemap_read,
1448 .open = pagemap_open,
1449 .release = pagemap_release,
1450};
1451#endif /* CONFIG_PROC_PAGE_MONITOR */
1452
1453#ifdef CONFIG_NUMA
1454
1455struct numa_maps {
1456 unsigned long pages;
1457 unsigned long anon;
1458 unsigned long active;
1459 unsigned long writeback;
1460 unsigned long mapcount_max;
1461 unsigned long dirty;
1462 unsigned long swapcache;
1463 unsigned long node[MAX_NUMNODES];
1464};
1465
1466struct numa_maps_private {
1467 struct proc_maps_private proc_maps;
1468 struct numa_maps md;
1469};
1470
1471static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
1472 unsigned long nr_pages)
1473{
1474 int count = page_mapcount(page);
1475
1476 md->pages += nr_pages;
1477 if (pte_dirty || PageDirty(page))
1478 md->dirty += nr_pages;
1479
1480 if (PageSwapCache(page))
1481 md->swapcache += nr_pages;
1482
1483 if (PageActive(page) || PageUnevictable(page))
1484 md->active += nr_pages;
1485
1486 if (PageWriteback(page))
1487 md->writeback += nr_pages;
1488
1489 if (PageAnon(page))
1490 md->anon += nr_pages;
1491
1492 if (count > md->mapcount_max)
1493 md->mapcount_max = count;
1494
1495 md->node[page_to_nid(page)] += nr_pages;
1496}
1497
1498static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
1499 unsigned long addr)
1500{
1501 struct page *page;
1502 int nid;
1503
1504 if (!pte_present(pte))
1505 return NULL;
1506
1507 page = vm_normal_page(vma, addr, pte);
1508 if (!page)
1509 return NULL;
1510
1511 if (PageReserved(page))
1512 return NULL;
1513
1514 nid = page_to_nid(page);
1515 if (!node_isset(nid, node_states[N_MEMORY]))
1516 return NULL;
1517
1518 return page;
1519}
1520
1521#ifdef CONFIG_TRANSPARENT_HUGEPAGE
1522static struct page *can_gather_numa_stats_pmd(pmd_t pmd,
1523 struct vm_area_struct *vma,
1524 unsigned long addr)
1525{
1526 struct page *page;
1527 int nid;
1528
1529 if (!pmd_present(pmd))
1530 return NULL;
1531
1532 page = vm_normal_page_pmd(vma, addr, pmd);
1533 if (!page)
1534 return NULL;
1535
1536 if (PageReserved(page))
1537 return NULL;
1538
1539 nid = page_to_nid(page);
1540 if (!node_isset(nid, node_states[N_MEMORY]))
1541 return NULL;
1542
1543 return page;
1544}
1545#endif
1546
1547static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
1548 unsigned long end, struct mm_walk *walk)
1549{
1550 struct numa_maps *md = walk->private;
1551 struct vm_area_struct *vma = walk->vma;
1552 spinlock_t *ptl;
1553 pte_t *orig_pte;
1554 pte_t *pte;
1555
1556#ifdef CONFIG_TRANSPARENT_HUGEPAGE
1557 ptl = pmd_trans_huge_lock(pmd, vma);
1558 if (ptl) {
1559 struct page *page;
1560
1561 page = can_gather_numa_stats_pmd(*pmd, vma, addr);
1562 if (page)
1563 gather_stats(page, md, pmd_dirty(*pmd),
1564 HPAGE_PMD_SIZE/PAGE_SIZE);
1565 spin_unlock(ptl);
1566 return 0;
1567 }
1568
1569 if (pmd_trans_unstable(pmd))
1570 return 0;
1571#endif
1572 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
1573 do {
1574 struct page *page = can_gather_numa_stats(*pte, vma, addr);
1575 if (!page)
1576 continue;
1577 gather_stats(page, md, pte_dirty(*pte), 1);
1578
1579 } while (pte++, addr += PAGE_SIZE, addr != end);
1580 pte_unmap_unlock(orig_pte, ptl);
1581 return 0;
1582}
1583#ifdef CONFIG_HUGETLB_PAGE
1584static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1585 unsigned long addr, unsigned long end, struct mm_walk *walk)
1586{
1587 pte_t huge_pte = huge_ptep_get(pte);
1588 struct numa_maps *md;
1589 struct page *page;
1590
1591 if (!pte_present(huge_pte))
1592 return 0;
1593
1594 page = pte_page(huge_pte);
1595 if (!page)
1596 return 0;
1597
1598 md = walk->private;
1599 gather_stats(page, md, pte_dirty(huge_pte), 1);
1600 return 0;
1601}
1602
1603#else
1604static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1605 unsigned long addr, unsigned long end, struct mm_walk *walk)
1606{
1607 return 0;
1608}
1609#endif
1610
1611/*
1612 * Display pages allocated per node and memory policy via /proc.
1613 */
1614static int show_numa_map(struct seq_file *m, void *v, int is_pid)
1615{
1616 struct numa_maps_private *numa_priv = m->private;
1617 struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
1618 struct vm_area_struct *vma = v;
1619 struct numa_maps *md = &numa_priv->md;
1620 struct file *file = vma->vm_file;
1621 struct mm_struct *mm = vma->vm_mm;
1622 struct mm_walk walk = {
1623 .hugetlb_entry = gather_hugetlb_stats,
1624 .pmd_entry = gather_pte_stats,
1625 .private = md,
1626 .mm = mm,
1627 };
1628 struct mempolicy *pol;
1629 char buffer[64];
1630 int nid;
1631
1632 if (!mm)
1633 return 0;
1634
1635 /* Ensure we start with an empty set of numa_maps statistics. */
1636 memset(md, 0, sizeof(*md));
1637
1638 pol = __get_vma_policy(vma, vma->vm_start);
1639 if (pol) {
1640 mpol_to_str(buffer, sizeof(buffer), pol);
1641 mpol_cond_put(pol);
1642 } else {
1643 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy);
1644 }
1645
1646 seq_printf(m, "%08lx %s", vma->vm_start, buffer);
1647
1648 if (file) {
1649 seq_puts(m, " file=");
1650 seq_file_path(m, file, "\n\t= ");
1651 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1652 seq_puts(m, " heap");
1653 } else if (is_stack(proc_priv, vma, is_pid)) {
1654 seq_puts(m, " stack");
1655 }
1656
1657 if (is_vm_hugetlb_page(vma))
1658 seq_puts(m, " huge");
1659
1660 /* mmap_sem is held by m_start */
1661 walk_page_vma(vma, &walk);
1662
1663 if (!md->pages)
1664 goto out;
1665
1666 if (md->anon)
1667 seq_printf(m, " anon=%lu", md->anon);
1668
1669 if (md->dirty)
1670 seq_printf(m, " dirty=%lu", md->dirty);
1671
1672 if (md->pages != md->anon && md->pages != md->dirty)
1673 seq_printf(m, " mapped=%lu", md->pages);
1674
1675 if (md->mapcount_max > 1)
1676 seq_printf(m, " mapmax=%lu", md->mapcount_max);
1677
1678 if (md->swapcache)
1679 seq_printf(m, " swapcache=%lu", md->swapcache);
1680
1681 if (md->active < md->pages && !is_vm_hugetlb_page(vma))
1682 seq_printf(m, " active=%lu", md->active);
1683
1684 if (md->writeback)
1685 seq_printf(m, " writeback=%lu", md->writeback);
1686
1687 for_each_node_state(nid, N_MEMORY)
1688 if (md->node[nid])
1689 seq_printf(m, " N%d=%lu", nid, md->node[nid]);
1690
1691 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10);
1692out:
1693 seq_putc(m, '\n');
1694 m_cache_vma(m, vma);
1695 return 0;
1696}
1697
1698static int show_pid_numa_map(struct seq_file *m, void *v)
1699{
1700 return show_numa_map(m, v, 1);
1701}
1702
1703static int show_tid_numa_map(struct seq_file *m, void *v)
1704{
1705 return show_numa_map(m, v, 0);
1706}
1707
1708static const struct seq_operations proc_pid_numa_maps_op = {
1709 .start = m_start,
1710 .next = m_next,
1711 .stop = m_stop,
1712 .show = show_pid_numa_map,
1713};
1714
1715static const struct seq_operations proc_tid_numa_maps_op = {
1716 .start = m_start,
1717 .next = m_next,
1718 .stop = m_stop,
1719 .show = show_tid_numa_map,
1720};
1721
1722static int numa_maps_open(struct inode *inode, struct file *file,
1723 const struct seq_operations *ops)
1724{
1725 return proc_maps_open(inode, file, ops,
1726 sizeof(struct numa_maps_private));
1727}
1728
1729static int pid_numa_maps_open(struct inode *inode, struct file *file)
1730{
1731 return numa_maps_open(inode, file, &proc_pid_numa_maps_op);
1732}
1733
1734static int tid_numa_maps_open(struct inode *inode, struct file *file)
1735{
1736 return numa_maps_open(inode, file, &proc_tid_numa_maps_op);
1737}
1738
1739const struct file_operations proc_pid_numa_maps_operations = {
1740 .open = pid_numa_maps_open,
1741 .read = seq_read,
1742 .llseek = seq_lseek,
1743 .release = proc_map_release,
1744};
1745
1746const struct file_operations proc_tid_numa_maps_operations = {
1747 .open = tid_numa_maps_open,
1748 .read = seq_read,
1749 .llseek = seq_lseek,
1750 .release = proc_map_release,
1751};
1752#endif /* CONFIG_NUMA */
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/ksm.h>
8#include <linux/seq_file.h>
9#include <linux/highmem.h>
10#include <linux/ptrace.h>
11#include <linux/slab.h>
12#include <linux/pagemap.h>
13#include <linux/mempolicy.h>
14#include <linux/rmap.h>
15#include <linux/swap.h>
16#include <linux/sched/mm.h>
17#include <linux/swapops.h>
18#include <linux/mmu_notifier.h>
19#include <linux/page_idle.h>
20#include <linux/shmem_fs.h>
21#include <linux/uaccess.h>
22#include <linux/pkeys.h>
23#include <linux/minmax.h>
24#include <linux/overflow.h>
25
26#include <asm/elf.h>
27#include <asm/tlb.h>
28#include <asm/tlbflush.h>
29#include "internal.h"
30
31#define SEQ_PUT_DEC(str, val) \
32 seq_put_decimal_ull_width(m, str, (val) << (PAGE_SHIFT-10), 8)
33void task_mem(struct seq_file *m, struct mm_struct *mm)
34{
35 unsigned long text, lib, swap, anon, file, shmem;
36 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
37
38 anon = get_mm_counter(mm, MM_ANONPAGES);
39 file = get_mm_counter(mm, MM_FILEPAGES);
40 shmem = get_mm_counter(mm, MM_SHMEMPAGES);
41
42 /*
43 * Note: to minimize their overhead, mm maintains hiwater_vm and
44 * hiwater_rss only when about to *lower* total_vm or rss. Any
45 * collector of these hiwater stats must therefore get total_vm
46 * and rss too, which will usually be the higher. Barriers? not
47 * worth the effort, such snapshots can always be inconsistent.
48 */
49 hiwater_vm = total_vm = mm->total_vm;
50 if (hiwater_vm < mm->hiwater_vm)
51 hiwater_vm = mm->hiwater_vm;
52 hiwater_rss = total_rss = anon + file + shmem;
53 if (hiwater_rss < mm->hiwater_rss)
54 hiwater_rss = mm->hiwater_rss;
55
56 /* split executable areas between text and lib */
57 text = PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK);
58 text = min(text, mm->exec_vm << PAGE_SHIFT);
59 lib = (mm->exec_vm << PAGE_SHIFT) - text;
60
61 swap = get_mm_counter(mm, MM_SWAPENTS);
62 SEQ_PUT_DEC("VmPeak:\t", hiwater_vm);
63 SEQ_PUT_DEC(" kB\nVmSize:\t", total_vm);
64 SEQ_PUT_DEC(" kB\nVmLck:\t", mm->locked_vm);
65 SEQ_PUT_DEC(" kB\nVmPin:\t", atomic64_read(&mm->pinned_vm));
66 SEQ_PUT_DEC(" kB\nVmHWM:\t", hiwater_rss);
67 SEQ_PUT_DEC(" kB\nVmRSS:\t", total_rss);
68 SEQ_PUT_DEC(" kB\nRssAnon:\t", anon);
69 SEQ_PUT_DEC(" kB\nRssFile:\t", file);
70 SEQ_PUT_DEC(" kB\nRssShmem:\t", shmem);
71 SEQ_PUT_DEC(" kB\nVmData:\t", mm->data_vm);
72 SEQ_PUT_DEC(" kB\nVmStk:\t", mm->stack_vm);
73 seq_put_decimal_ull_width(m,
74 " kB\nVmExe:\t", text >> 10, 8);
75 seq_put_decimal_ull_width(m,
76 " kB\nVmLib:\t", lib >> 10, 8);
77 seq_put_decimal_ull_width(m,
78 " kB\nVmPTE:\t", mm_pgtables_bytes(mm) >> 10, 8);
79 SEQ_PUT_DEC(" kB\nVmSwap:\t", swap);
80 seq_puts(m, " kB\n");
81 hugetlb_report_usage(m, mm);
82}
83#undef SEQ_PUT_DEC
84
85unsigned long task_vsize(struct mm_struct *mm)
86{
87 return PAGE_SIZE * mm->total_vm;
88}
89
90unsigned long task_statm(struct mm_struct *mm,
91 unsigned long *shared, unsigned long *text,
92 unsigned long *data, unsigned long *resident)
93{
94 *shared = get_mm_counter(mm, MM_FILEPAGES) +
95 get_mm_counter(mm, MM_SHMEMPAGES);
96 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
97 >> PAGE_SHIFT;
98 *data = mm->data_vm + mm->stack_vm;
99 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
100 return mm->total_vm;
101}
102
103#ifdef CONFIG_NUMA
104/*
105 * Save get_task_policy() for show_numa_map().
106 */
107static void hold_task_mempolicy(struct proc_maps_private *priv)
108{
109 struct task_struct *task = priv->task;
110
111 task_lock(task);
112 priv->task_mempolicy = get_task_policy(task);
113 mpol_get(priv->task_mempolicy);
114 task_unlock(task);
115}
116static void release_task_mempolicy(struct proc_maps_private *priv)
117{
118 mpol_put(priv->task_mempolicy);
119}
120#else
121static void hold_task_mempolicy(struct proc_maps_private *priv)
122{
123}
124static void release_task_mempolicy(struct proc_maps_private *priv)
125{
126}
127#endif
128
129static struct vm_area_struct *proc_get_vma(struct proc_maps_private *priv,
130 loff_t *ppos)
131{
132 struct vm_area_struct *vma = vma_next(&priv->iter);
133
134 if (vma) {
135 *ppos = vma->vm_start;
136 } else {
137 *ppos = -2UL;
138 vma = get_gate_vma(priv->mm);
139 }
140
141 return vma;
142}
143
144static void *m_start(struct seq_file *m, loff_t *ppos)
145{
146 struct proc_maps_private *priv = m->private;
147 unsigned long last_addr = *ppos;
148 struct mm_struct *mm;
149
150 /* See m_next(). Zero at the start or after lseek. */
151 if (last_addr == -1UL)
152 return NULL;
153
154 priv->task = get_proc_task(priv->inode);
155 if (!priv->task)
156 return ERR_PTR(-ESRCH);
157
158 mm = priv->mm;
159 if (!mm || !mmget_not_zero(mm)) {
160 put_task_struct(priv->task);
161 priv->task = NULL;
162 return NULL;
163 }
164
165 if (mmap_read_lock_killable(mm)) {
166 mmput(mm);
167 put_task_struct(priv->task);
168 priv->task = NULL;
169 return ERR_PTR(-EINTR);
170 }
171
172 vma_iter_init(&priv->iter, mm, last_addr);
173 hold_task_mempolicy(priv);
174 if (last_addr == -2UL)
175 return get_gate_vma(mm);
176
177 return proc_get_vma(priv, ppos);
178}
179
180static void *m_next(struct seq_file *m, void *v, loff_t *ppos)
181{
182 if (*ppos == -2UL) {
183 *ppos = -1UL;
184 return NULL;
185 }
186 return proc_get_vma(m->private, ppos);
187}
188
189static void m_stop(struct seq_file *m, void *v)
190{
191 struct proc_maps_private *priv = m->private;
192 struct mm_struct *mm = priv->mm;
193
194 if (!priv->task)
195 return;
196
197 release_task_mempolicy(priv);
198 mmap_read_unlock(mm);
199 mmput(mm);
200 put_task_struct(priv->task);
201 priv->task = NULL;
202}
203
204static int proc_maps_open(struct inode *inode, struct file *file,
205 const struct seq_operations *ops, int psize)
206{
207 struct proc_maps_private *priv = __seq_open_private(file, ops, psize);
208
209 if (!priv)
210 return -ENOMEM;
211
212 priv->inode = inode;
213 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
214 if (IS_ERR(priv->mm)) {
215 int err = PTR_ERR(priv->mm);
216
217 seq_release_private(inode, file);
218 return err;
219 }
220
221 return 0;
222}
223
224static int proc_map_release(struct inode *inode, struct file *file)
225{
226 struct seq_file *seq = file->private_data;
227 struct proc_maps_private *priv = seq->private;
228
229 if (priv->mm)
230 mmdrop(priv->mm);
231
232 return seq_release_private(inode, file);
233}
234
235static int do_maps_open(struct inode *inode, struct file *file,
236 const struct seq_operations *ops)
237{
238 return proc_maps_open(inode, file, ops,
239 sizeof(struct proc_maps_private));
240}
241
242static void show_vma_header_prefix(struct seq_file *m,
243 unsigned long start, unsigned long end,
244 vm_flags_t flags, unsigned long long pgoff,
245 dev_t dev, unsigned long ino)
246{
247 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
248 seq_put_hex_ll(m, NULL, start, 8);
249 seq_put_hex_ll(m, "-", end, 8);
250 seq_putc(m, ' ');
251 seq_putc(m, flags & VM_READ ? 'r' : '-');
252 seq_putc(m, flags & VM_WRITE ? 'w' : '-');
253 seq_putc(m, flags & VM_EXEC ? 'x' : '-');
254 seq_putc(m, flags & VM_MAYSHARE ? 's' : 'p');
255 seq_put_hex_ll(m, " ", pgoff, 8);
256 seq_put_hex_ll(m, " ", MAJOR(dev), 2);
257 seq_put_hex_ll(m, ":", MINOR(dev), 2);
258 seq_put_decimal_ull(m, " ", ino);
259 seq_putc(m, ' ');
260}
261
262static void
263show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
264{
265 struct anon_vma_name *anon_name = NULL;
266 struct mm_struct *mm = vma->vm_mm;
267 struct file *file = vma->vm_file;
268 vm_flags_t flags = vma->vm_flags;
269 unsigned long ino = 0;
270 unsigned long long pgoff = 0;
271 unsigned long start, end;
272 dev_t dev = 0;
273 const char *name = NULL;
274
275 if (file) {
276 const struct inode *inode = file_user_inode(vma->vm_file);
277
278 dev = inode->i_sb->s_dev;
279 ino = inode->i_ino;
280 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
281 }
282
283 start = vma->vm_start;
284 end = vma->vm_end;
285 show_vma_header_prefix(m, start, end, flags, pgoff, dev, ino);
286 if (mm)
287 anon_name = anon_vma_name(vma);
288
289 /*
290 * Print the dentry name for named mappings, and a
291 * special [heap] marker for the heap:
292 */
293 if (file) {
294 seq_pad(m, ' ');
295 /*
296 * If user named this anon shared memory via
297 * prctl(PR_SET_VMA ..., use the provided name.
298 */
299 if (anon_name)
300 seq_printf(m, "[anon_shmem:%s]", anon_name->name);
301 else
302 seq_path(m, file_user_path(file), "\n");
303 goto done;
304 }
305
306 if (vma->vm_ops && vma->vm_ops->name) {
307 name = vma->vm_ops->name(vma);
308 if (name)
309 goto done;
310 }
311
312 name = arch_vma_name(vma);
313 if (!name) {
314 if (!mm) {
315 name = "[vdso]";
316 goto done;
317 }
318
319 if (vma_is_initial_heap(vma)) {
320 name = "[heap]";
321 goto done;
322 }
323
324 if (vma_is_initial_stack(vma)) {
325 name = "[stack]";
326 goto done;
327 }
328
329 if (anon_name) {
330 seq_pad(m, ' ');
331 seq_printf(m, "[anon:%s]", anon_name->name);
332 }
333 }
334
335done:
336 if (name) {
337 seq_pad(m, ' ');
338 seq_puts(m, name);
339 }
340 seq_putc(m, '\n');
341}
342
343static int show_map(struct seq_file *m, void *v)
344{
345 show_map_vma(m, v);
346 return 0;
347}
348
349static const struct seq_operations proc_pid_maps_op = {
350 .start = m_start,
351 .next = m_next,
352 .stop = m_stop,
353 .show = show_map
354};
355
356static int pid_maps_open(struct inode *inode, struct file *file)
357{
358 return do_maps_open(inode, file, &proc_pid_maps_op);
359}
360
361const struct file_operations proc_pid_maps_operations = {
362 .open = pid_maps_open,
363 .read = seq_read,
364 .llseek = seq_lseek,
365 .release = proc_map_release,
366};
367
368/*
369 * Proportional Set Size(PSS): my share of RSS.
370 *
371 * PSS of a process is the count of pages it has in memory, where each
372 * page is divided by the number of processes sharing it. So if a
373 * process has 1000 pages all to itself, and 1000 shared with one other
374 * process, its PSS will be 1500.
375 *
376 * To keep (accumulated) division errors low, we adopt a 64bit
377 * fixed-point pss counter to minimize division errors. So (pss >>
378 * PSS_SHIFT) would be the real byte count.
379 *
380 * A shift of 12 before division means (assuming 4K page size):
381 * - 1M 3-user-pages add up to 8KB errors;
382 * - supports mapcount up to 2^24, or 16M;
383 * - supports PSS up to 2^52 bytes, or 4PB.
384 */
385#define PSS_SHIFT 12
386
387#ifdef CONFIG_PROC_PAGE_MONITOR
388struct mem_size_stats {
389 unsigned long resident;
390 unsigned long shared_clean;
391 unsigned long shared_dirty;
392 unsigned long private_clean;
393 unsigned long private_dirty;
394 unsigned long referenced;
395 unsigned long anonymous;
396 unsigned long lazyfree;
397 unsigned long anonymous_thp;
398 unsigned long shmem_thp;
399 unsigned long file_thp;
400 unsigned long swap;
401 unsigned long shared_hugetlb;
402 unsigned long private_hugetlb;
403 unsigned long ksm;
404 u64 pss;
405 u64 pss_anon;
406 u64 pss_file;
407 u64 pss_shmem;
408 u64 pss_dirty;
409 u64 pss_locked;
410 u64 swap_pss;
411};
412
413static void smaps_page_accumulate(struct mem_size_stats *mss,
414 struct page *page, unsigned long size, unsigned long pss,
415 bool dirty, bool locked, bool private)
416{
417 mss->pss += pss;
418
419 if (PageAnon(page))
420 mss->pss_anon += pss;
421 else if (PageSwapBacked(page))
422 mss->pss_shmem += pss;
423 else
424 mss->pss_file += pss;
425
426 if (locked)
427 mss->pss_locked += pss;
428
429 if (dirty || PageDirty(page)) {
430 mss->pss_dirty += pss;
431 if (private)
432 mss->private_dirty += size;
433 else
434 mss->shared_dirty += size;
435 } else {
436 if (private)
437 mss->private_clean += size;
438 else
439 mss->shared_clean += size;
440 }
441}
442
443static void smaps_account(struct mem_size_stats *mss, struct page *page,
444 bool compound, bool young, bool dirty, bool locked,
445 bool migration)
446{
447 int i, nr = compound ? compound_nr(page) : 1;
448 unsigned long size = nr * PAGE_SIZE;
449
450 /*
451 * First accumulate quantities that depend only on |size| and the type
452 * of the compound page.
453 */
454 if (PageAnon(page)) {
455 mss->anonymous += size;
456 if (!PageSwapBacked(page) && !dirty && !PageDirty(page))
457 mss->lazyfree += size;
458 }
459
460 if (PageKsm(page))
461 mss->ksm += size;
462
463 mss->resident += size;
464 /* Accumulate the size in pages that have been accessed. */
465 if (young || page_is_young(page) || PageReferenced(page))
466 mss->referenced += size;
467
468 /*
469 * Then accumulate quantities that may depend on sharing, or that may
470 * differ page-by-page.
471 *
472 * page_count(page) == 1 guarantees the page is mapped exactly once.
473 * If any subpage of the compound page mapped with PTE it would elevate
474 * page_count().
475 *
476 * The page_mapcount() is called to get a snapshot of the mapcount.
477 * Without holding the page lock this snapshot can be slightly wrong as
478 * we cannot always read the mapcount atomically. It is not safe to
479 * call page_mapcount() even with PTL held if the page is not mapped,
480 * especially for migration entries. Treat regular migration entries
481 * as mapcount == 1.
482 */
483 if ((page_count(page) == 1) || migration) {
484 smaps_page_accumulate(mss, page, size, size << PSS_SHIFT, dirty,
485 locked, true);
486 return;
487 }
488 for (i = 0; i < nr; i++, page++) {
489 int mapcount = page_mapcount(page);
490 unsigned long pss = PAGE_SIZE << PSS_SHIFT;
491 if (mapcount >= 2)
492 pss /= mapcount;
493 smaps_page_accumulate(mss, page, PAGE_SIZE, pss, dirty, locked,
494 mapcount < 2);
495 }
496}
497
498#ifdef CONFIG_SHMEM
499static int smaps_pte_hole(unsigned long addr, unsigned long end,
500 __always_unused int depth, struct mm_walk *walk)
501{
502 struct mem_size_stats *mss = walk->private;
503 struct vm_area_struct *vma = walk->vma;
504
505 mss->swap += shmem_partial_swap_usage(walk->vma->vm_file->f_mapping,
506 linear_page_index(vma, addr),
507 linear_page_index(vma, end));
508
509 return 0;
510}
511#else
512#define smaps_pte_hole NULL
513#endif /* CONFIG_SHMEM */
514
515static void smaps_pte_hole_lookup(unsigned long addr, struct mm_walk *walk)
516{
517#ifdef CONFIG_SHMEM
518 if (walk->ops->pte_hole) {
519 /* depth is not used */
520 smaps_pte_hole(addr, addr + PAGE_SIZE, 0, walk);
521 }
522#endif
523}
524
525static void smaps_pte_entry(pte_t *pte, unsigned long addr,
526 struct mm_walk *walk)
527{
528 struct mem_size_stats *mss = walk->private;
529 struct vm_area_struct *vma = walk->vma;
530 bool locked = !!(vma->vm_flags & VM_LOCKED);
531 struct page *page = NULL;
532 bool migration = false, young = false, dirty = false;
533 pte_t ptent = ptep_get(pte);
534
535 if (pte_present(ptent)) {
536 page = vm_normal_page(vma, addr, ptent);
537 young = pte_young(ptent);
538 dirty = pte_dirty(ptent);
539 } else if (is_swap_pte(ptent)) {
540 swp_entry_t swpent = pte_to_swp_entry(ptent);
541
542 if (!non_swap_entry(swpent)) {
543 int mapcount;
544
545 mss->swap += PAGE_SIZE;
546 mapcount = swp_swapcount(swpent);
547 if (mapcount >= 2) {
548 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT;
549
550 do_div(pss_delta, mapcount);
551 mss->swap_pss += pss_delta;
552 } else {
553 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT;
554 }
555 } else if (is_pfn_swap_entry(swpent)) {
556 if (is_migration_entry(swpent))
557 migration = true;
558 page = pfn_swap_entry_to_page(swpent);
559 }
560 } else {
561 smaps_pte_hole_lookup(addr, walk);
562 return;
563 }
564
565 if (!page)
566 return;
567
568 smaps_account(mss, page, false, young, dirty, locked, migration);
569}
570
571#ifdef CONFIG_TRANSPARENT_HUGEPAGE
572static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
573 struct mm_walk *walk)
574{
575 struct mem_size_stats *mss = walk->private;
576 struct vm_area_struct *vma = walk->vma;
577 bool locked = !!(vma->vm_flags & VM_LOCKED);
578 struct page *page = NULL;
579 bool migration = false;
580
581 if (pmd_present(*pmd)) {
582 page = vm_normal_page_pmd(vma, addr, *pmd);
583 } else if (unlikely(thp_migration_supported() && is_swap_pmd(*pmd))) {
584 swp_entry_t entry = pmd_to_swp_entry(*pmd);
585
586 if (is_migration_entry(entry)) {
587 migration = true;
588 page = pfn_swap_entry_to_page(entry);
589 }
590 }
591 if (IS_ERR_OR_NULL(page))
592 return;
593 if (PageAnon(page))
594 mss->anonymous_thp += HPAGE_PMD_SIZE;
595 else if (PageSwapBacked(page))
596 mss->shmem_thp += HPAGE_PMD_SIZE;
597 else if (is_zone_device_page(page))
598 /* pass */;
599 else
600 mss->file_thp += HPAGE_PMD_SIZE;
601
602 smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd),
603 locked, migration);
604}
605#else
606static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
607 struct mm_walk *walk)
608{
609}
610#endif
611
612static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
613 struct mm_walk *walk)
614{
615 struct vm_area_struct *vma = walk->vma;
616 pte_t *pte;
617 spinlock_t *ptl;
618
619 ptl = pmd_trans_huge_lock(pmd, vma);
620 if (ptl) {
621 smaps_pmd_entry(pmd, addr, walk);
622 spin_unlock(ptl);
623 goto out;
624 }
625
626 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
627 if (!pte) {
628 walk->action = ACTION_AGAIN;
629 return 0;
630 }
631 for (; addr != end; pte++, addr += PAGE_SIZE)
632 smaps_pte_entry(pte, addr, walk);
633 pte_unmap_unlock(pte - 1, ptl);
634out:
635 cond_resched();
636 return 0;
637}
638
639static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
640{
641 /*
642 * Don't forget to update Documentation/ on changes.
643 */
644 static const char mnemonics[BITS_PER_LONG][2] = {
645 /*
646 * In case if we meet a flag we don't know about.
647 */
648 [0 ... (BITS_PER_LONG-1)] = "??",
649
650 [ilog2(VM_READ)] = "rd",
651 [ilog2(VM_WRITE)] = "wr",
652 [ilog2(VM_EXEC)] = "ex",
653 [ilog2(VM_SHARED)] = "sh",
654 [ilog2(VM_MAYREAD)] = "mr",
655 [ilog2(VM_MAYWRITE)] = "mw",
656 [ilog2(VM_MAYEXEC)] = "me",
657 [ilog2(VM_MAYSHARE)] = "ms",
658 [ilog2(VM_GROWSDOWN)] = "gd",
659 [ilog2(VM_PFNMAP)] = "pf",
660 [ilog2(VM_LOCKED)] = "lo",
661 [ilog2(VM_IO)] = "io",
662 [ilog2(VM_SEQ_READ)] = "sr",
663 [ilog2(VM_RAND_READ)] = "rr",
664 [ilog2(VM_DONTCOPY)] = "dc",
665 [ilog2(VM_DONTEXPAND)] = "de",
666 [ilog2(VM_LOCKONFAULT)] = "lf",
667 [ilog2(VM_ACCOUNT)] = "ac",
668 [ilog2(VM_NORESERVE)] = "nr",
669 [ilog2(VM_HUGETLB)] = "ht",
670 [ilog2(VM_SYNC)] = "sf",
671 [ilog2(VM_ARCH_1)] = "ar",
672 [ilog2(VM_WIPEONFORK)] = "wf",
673 [ilog2(VM_DONTDUMP)] = "dd",
674#ifdef CONFIG_ARM64_BTI
675 [ilog2(VM_ARM64_BTI)] = "bt",
676#endif
677#ifdef CONFIG_MEM_SOFT_DIRTY
678 [ilog2(VM_SOFTDIRTY)] = "sd",
679#endif
680 [ilog2(VM_MIXEDMAP)] = "mm",
681 [ilog2(VM_HUGEPAGE)] = "hg",
682 [ilog2(VM_NOHUGEPAGE)] = "nh",
683 [ilog2(VM_MERGEABLE)] = "mg",
684 [ilog2(VM_UFFD_MISSING)]= "um",
685 [ilog2(VM_UFFD_WP)] = "uw",
686#ifdef CONFIG_ARM64_MTE
687 [ilog2(VM_MTE)] = "mt",
688 [ilog2(VM_MTE_ALLOWED)] = "",
689#endif
690#ifdef CONFIG_ARCH_HAS_PKEYS
691 /* These come out via ProtectionKey: */
692 [ilog2(VM_PKEY_BIT0)] = "",
693 [ilog2(VM_PKEY_BIT1)] = "",
694 [ilog2(VM_PKEY_BIT2)] = "",
695 [ilog2(VM_PKEY_BIT3)] = "",
696#if VM_PKEY_BIT4
697 [ilog2(VM_PKEY_BIT4)] = "",
698#endif
699#endif /* CONFIG_ARCH_HAS_PKEYS */
700#ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR
701 [ilog2(VM_UFFD_MINOR)] = "ui",
702#endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */
703#ifdef CONFIG_X86_USER_SHADOW_STACK
704 [ilog2(VM_SHADOW_STACK)] = "ss",
705#endif
706 };
707 size_t i;
708
709 seq_puts(m, "VmFlags: ");
710 for (i = 0; i < BITS_PER_LONG; i++) {
711 if (!mnemonics[i][0])
712 continue;
713 if (vma->vm_flags & (1UL << i)) {
714 seq_putc(m, mnemonics[i][0]);
715 seq_putc(m, mnemonics[i][1]);
716 seq_putc(m, ' ');
717 }
718 }
719 seq_putc(m, '\n');
720}
721
722#ifdef CONFIG_HUGETLB_PAGE
723static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,
724 unsigned long addr, unsigned long end,
725 struct mm_walk *walk)
726{
727 struct mem_size_stats *mss = walk->private;
728 struct vm_area_struct *vma = walk->vma;
729 struct page *page = NULL;
730 pte_t ptent = ptep_get(pte);
731
732 if (pte_present(ptent)) {
733 page = vm_normal_page(vma, addr, ptent);
734 } else if (is_swap_pte(ptent)) {
735 swp_entry_t swpent = pte_to_swp_entry(ptent);
736
737 if (is_pfn_swap_entry(swpent))
738 page = pfn_swap_entry_to_page(swpent);
739 }
740 if (page) {
741 if (page_mapcount(page) >= 2 || hugetlb_pmd_shared(pte))
742 mss->shared_hugetlb += huge_page_size(hstate_vma(vma));
743 else
744 mss->private_hugetlb += huge_page_size(hstate_vma(vma));
745 }
746 return 0;
747}
748#else
749#define smaps_hugetlb_range NULL
750#endif /* HUGETLB_PAGE */
751
752static const struct mm_walk_ops smaps_walk_ops = {
753 .pmd_entry = smaps_pte_range,
754 .hugetlb_entry = smaps_hugetlb_range,
755 .walk_lock = PGWALK_RDLOCK,
756};
757
758static const struct mm_walk_ops smaps_shmem_walk_ops = {
759 .pmd_entry = smaps_pte_range,
760 .hugetlb_entry = smaps_hugetlb_range,
761 .pte_hole = smaps_pte_hole,
762 .walk_lock = PGWALK_RDLOCK,
763};
764
765/*
766 * Gather mem stats from @vma with the indicated beginning
767 * address @start, and keep them in @mss.
768 *
769 * Use vm_start of @vma as the beginning address if @start is 0.
770 */
771static void smap_gather_stats(struct vm_area_struct *vma,
772 struct mem_size_stats *mss, unsigned long start)
773{
774 const struct mm_walk_ops *ops = &smaps_walk_ops;
775
776 /* Invalid start */
777 if (start >= vma->vm_end)
778 return;
779
780 if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) {
781 /*
782 * For shared or readonly shmem mappings we know that all
783 * swapped out pages belong to the shmem object, and we can
784 * obtain the swap value much more efficiently. For private
785 * writable mappings, we might have COW pages that are
786 * not affected by the parent swapped out pages of the shmem
787 * object, so we have to distinguish them during the page walk.
788 * Unless we know that the shmem object (or the part mapped by
789 * our VMA) has no swapped out pages at all.
790 */
791 unsigned long shmem_swapped = shmem_swap_usage(vma);
792
793 if (!start && (!shmem_swapped || (vma->vm_flags & VM_SHARED) ||
794 !(vma->vm_flags & VM_WRITE))) {
795 mss->swap += shmem_swapped;
796 } else {
797 ops = &smaps_shmem_walk_ops;
798 }
799 }
800
801 /* mmap_lock is held in m_start */
802 if (!start)
803 walk_page_vma(vma, ops, mss);
804 else
805 walk_page_range(vma->vm_mm, start, vma->vm_end, ops, mss);
806}
807
808#define SEQ_PUT_DEC(str, val) \
809 seq_put_decimal_ull_width(m, str, (val) >> 10, 8)
810
811/* Show the contents common for smaps and smaps_rollup */
812static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss,
813 bool rollup_mode)
814{
815 SEQ_PUT_DEC("Rss: ", mss->resident);
816 SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT);
817 SEQ_PUT_DEC(" kB\nPss_Dirty: ", mss->pss_dirty >> PSS_SHIFT);
818 if (rollup_mode) {
819 /*
820 * These are meaningful only for smaps_rollup, otherwise two of
821 * them are zero, and the other one is the same as Pss.
822 */
823 SEQ_PUT_DEC(" kB\nPss_Anon: ",
824 mss->pss_anon >> PSS_SHIFT);
825 SEQ_PUT_DEC(" kB\nPss_File: ",
826 mss->pss_file >> PSS_SHIFT);
827 SEQ_PUT_DEC(" kB\nPss_Shmem: ",
828 mss->pss_shmem >> PSS_SHIFT);
829 }
830 SEQ_PUT_DEC(" kB\nShared_Clean: ", mss->shared_clean);
831 SEQ_PUT_DEC(" kB\nShared_Dirty: ", mss->shared_dirty);
832 SEQ_PUT_DEC(" kB\nPrivate_Clean: ", mss->private_clean);
833 SEQ_PUT_DEC(" kB\nPrivate_Dirty: ", mss->private_dirty);
834 SEQ_PUT_DEC(" kB\nReferenced: ", mss->referenced);
835 SEQ_PUT_DEC(" kB\nAnonymous: ", mss->anonymous);
836 SEQ_PUT_DEC(" kB\nKSM: ", mss->ksm);
837 SEQ_PUT_DEC(" kB\nLazyFree: ", mss->lazyfree);
838 SEQ_PUT_DEC(" kB\nAnonHugePages: ", mss->anonymous_thp);
839 SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp);
840 SEQ_PUT_DEC(" kB\nFilePmdMapped: ", mss->file_thp);
841 SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb);
842 seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ",
843 mss->private_hugetlb >> 10, 7);
844 SEQ_PUT_DEC(" kB\nSwap: ", mss->swap);
845 SEQ_PUT_DEC(" kB\nSwapPss: ",
846 mss->swap_pss >> PSS_SHIFT);
847 SEQ_PUT_DEC(" kB\nLocked: ",
848 mss->pss_locked >> PSS_SHIFT);
849 seq_puts(m, " kB\n");
850}
851
852static int show_smap(struct seq_file *m, void *v)
853{
854 struct vm_area_struct *vma = v;
855 struct mem_size_stats mss = {};
856
857 smap_gather_stats(vma, &mss, 0);
858
859 show_map_vma(m, vma);
860
861 SEQ_PUT_DEC("Size: ", vma->vm_end - vma->vm_start);
862 SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma));
863 SEQ_PUT_DEC(" kB\nMMUPageSize: ", vma_mmu_pagesize(vma));
864 seq_puts(m, " kB\n");
865
866 __show_smap(m, &mss, false);
867
868 seq_printf(m, "THPeligible: %8u\n",
869 !!thp_vma_allowable_orders(vma, vma->vm_flags, true, false,
870 true, THP_ORDERS_ALL));
871
872 if (arch_pkeys_enabled())
873 seq_printf(m, "ProtectionKey: %8u\n", vma_pkey(vma));
874 show_smap_vma_flags(m, vma);
875
876 return 0;
877}
878
879static int show_smaps_rollup(struct seq_file *m, void *v)
880{
881 struct proc_maps_private *priv = m->private;
882 struct mem_size_stats mss = {};
883 struct mm_struct *mm = priv->mm;
884 struct vm_area_struct *vma;
885 unsigned long vma_start = 0, last_vma_end = 0;
886 int ret = 0;
887 VMA_ITERATOR(vmi, mm, 0);
888
889 priv->task = get_proc_task(priv->inode);
890 if (!priv->task)
891 return -ESRCH;
892
893 if (!mm || !mmget_not_zero(mm)) {
894 ret = -ESRCH;
895 goto out_put_task;
896 }
897
898 ret = mmap_read_lock_killable(mm);
899 if (ret)
900 goto out_put_mm;
901
902 hold_task_mempolicy(priv);
903 vma = vma_next(&vmi);
904
905 if (unlikely(!vma))
906 goto empty_set;
907
908 vma_start = vma->vm_start;
909 do {
910 smap_gather_stats(vma, &mss, 0);
911 last_vma_end = vma->vm_end;
912
913 /*
914 * Release mmap_lock temporarily if someone wants to
915 * access it for write request.
916 */
917 if (mmap_lock_is_contended(mm)) {
918 vma_iter_invalidate(&vmi);
919 mmap_read_unlock(mm);
920 ret = mmap_read_lock_killable(mm);
921 if (ret) {
922 release_task_mempolicy(priv);
923 goto out_put_mm;
924 }
925
926 /*
927 * After dropping the lock, there are four cases to
928 * consider. See the following example for explanation.
929 *
930 * +------+------+-----------+
931 * | VMA1 | VMA2 | VMA3 |
932 * +------+------+-----------+
933 * | | | |
934 * 4k 8k 16k 400k
935 *
936 * Suppose we drop the lock after reading VMA2 due to
937 * contention, then we get:
938 *
939 * last_vma_end = 16k
940 *
941 * 1) VMA2 is freed, but VMA3 exists:
942 *
943 * vma_next(vmi) will return VMA3.
944 * In this case, just continue from VMA3.
945 *
946 * 2) VMA2 still exists:
947 *
948 * vma_next(vmi) will return VMA3.
949 * In this case, just continue from VMA3.
950 *
951 * 3) No more VMAs can be found:
952 *
953 * vma_next(vmi) will return NULL.
954 * No more things to do, just break.
955 *
956 * 4) (last_vma_end - 1) is the middle of a vma (VMA'):
957 *
958 * vma_next(vmi) will return VMA' whose range
959 * contains last_vma_end.
960 * Iterate VMA' from last_vma_end.
961 */
962 vma = vma_next(&vmi);
963 /* Case 3 above */
964 if (!vma)
965 break;
966
967 /* Case 1 and 2 above */
968 if (vma->vm_start >= last_vma_end)
969 continue;
970
971 /* Case 4 above */
972 if (vma->vm_end > last_vma_end)
973 smap_gather_stats(vma, &mss, last_vma_end);
974 }
975 } for_each_vma(vmi, vma);
976
977empty_set:
978 show_vma_header_prefix(m, vma_start, last_vma_end, 0, 0, 0, 0);
979 seq_pad(m, ' ');
980 seq_puts(m, "[rollup]\n");
981
982 __show_smap(m, &mss, true);
983
984 release_task_mempolicy(priv);
985 mmap_read_unlock(mm);
986
987out_put_mm:
988 mmput(mm);
989out_put_task:
990 put_task_struct(priv->task);
991 priv->task = NULL;
992
993 return ret;
994}
995#undef SEQ_PUT_DEC
996
997static const struct seq_operations proc_pid_smaps_op = {
998 .start = m_start,
999 .next = m_next,
1000 .stop = m_stop,
1001 .show = show_smap
1002};
1003
1004static int pid_smaps_open(struct inode *inode, struct file *file)
1005{
1006 return do_maps_open(inode, file, &proc_pid_smaps_op);
1007}
1008
1009static int smaps_rollup_open(struct inode *inode, struct file *file)
1010{
1011 int ret;
1012 struct proc_maps_private *priv;
1013
1014 priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT);
1015 if (!priv)
1016 return -ENOMEM;
1017
1018 ret = single_open(file, show_smaps_rollup, priv);
1019 if (ret)
1020 goto out_free;
1021
1022 priv->inode = inode;
1023 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
1024 if (IS_ERR(priv->mm)) {
1025 ret = PTR_ERR(priv->mm);
1026
1027 single_release(inode, file);
1028 goto out_free;
1029 }
1030
1031 return 0;
1032
1033out_free:
1034 kfree(priv);
1035 return ret;
1036}
1037
1038static int smaps_rollup_release(struct inode *inode, struct file *file)
1039{
1040 struct seq_file *seq = file->private_data;
1041 struct proc_maps_private *priv = seq->private;
1042
1043 if (priv->mm)
1044 mmdrop(priv->mm);
1045
1046 kfree(priv);
1047 return single_release(inode, file);
1048}
1049
1050const struct file_operations proc_pid_smaps_operations = {
1051 .open = pid_smaps_open,
1052 .read = seq_read,
1053 .llseek = seq_lseek,
1054 .release = proc_map_release,
1055};
1056
1057const struct file_operations proc_pid_smaps_rollup_operations = {
1058 .open = smaps_rollup_open,
1059 .read = seq_read,
1060 .llseek = seq_lseek,
1061 .release = smaps_rollup_release,
1062};
1063
1064enum clear_refs_types {
1065 CLEAR_REFS_ALL = 1,
1066 CLEAR_REFS_ANON,
1067 CLEAR_REFS_MAPPED,
1068 CLEAR_REFS_SOFT_DIRTY,
1069 CLEAR_REFS_MM_HIWATER_RSS,
1070 CLEAR_REFS_LAST,
1071};
1072
1073struct clear_refs_private {
1074 enum clear_refs_types type;
1075};
1076
1077#ifdef CONFIG_MEM_SOFT_DIRTY
1078
1079static inline bool pte_is_pinned(struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1080{
1081 struct page *page;
1082
1083 if (!pte_write(pte))
1084 return false;
1085 if (!is_cow_mapping(vma->vm_flags))
1086 return false;
1087 if (likely(!test_bit(MMF_HAS_PINNED, &vma->vm_mm->flags)))
1088 return false;
1089 page = vm_normal_page(vma, addr, pte);
1090 if (!page)
1091 return false;
1092 return page_maybe_dma_pinned(page);
1093}
1094
1095static inline void clear_soft_dirty(struct vm_area_struct *vma,
1096 unsigned long addr, pte_t *pte)
1097{
1098 /*
1099 * The soft-dirty tracker uses #PF-s to catch writes
1100 * to pages, so write-protect the pte as well. See the
1101 * Documentation/admin-guide/mm/soft-dirty.rst for full description
1102 * of how soft-dirty works.
1103 */
1104 pte_t ptent = ptep_get(pte);
1105
1106 if (pte_present(ptent)) {
1107 pte_t old_pte;
1108
1109 if (pte_is_pinned(vma, addr, ptent))
1110 return;
1111 old_pte = ptep_modify_prot_start(vma, addr, pte);
1112 ptent = pte_wrprotect(old_pte);
1113 ptent = pte_clear_soft_dirty(ptent);
1114 ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent);
1115 } else if (is_swap_pte(ptent)) {
1116 ptent = pte_swp_clear_soft_dirty(ptent);
1117 set_pte_at(vma->vm_mm, addr, pte, ptent);
1118 }
1119}
1120#else
1121static inline void clear_soft_dirty(struct vm_area_struct *vma,
1122 unsigned long addr, pte_t *pte)
1123{
1124}
1125#endif
1126
1127#if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
1128static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
1129 unsigned long addr, pmd_t *pmdp)
1130{
1131 pmd_t old, pmd = *pmdp;
1132
1133 if (pmd_present(pmd)) {
1134 /* See comment in change_huge_pmd() */
1135 old = pmdp_invalidate(vma, addr, pmdp);
1136 if (pmd_dirty(old))
1137 pmd = pmd_mkdirty(pmd);
1138 if (pmd_young(old))
1139 pmd = pmd_mkyoung(pmd);
1140
1141 pmd = pmd_wrprotect(pmd);
1142 pmd = pmd_clear_soft_dirty(pmd);
1143
1144 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
1145 } else if (is_migration_entry(pmd_to_swp_entry(pmd))) {
1146 pmd = pmd_swp_clear_soft_dirty(pmd);
1147 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
1148 }
1149}
1150#else
1151static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
1152 unsigned long addr, pmd_t *pmdp)
1153{
1154}
1155#endif
1156
1157static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
1158 unsigned long end, struct mm_walk *walk)
1159{
1160 struct clear_refs_private *cp = walk->private;
1161 struct vm_area_struct *vma = walk->vma;
1162 pte_t *pte, ptent;
1163 spinlock_t *ptl;
1164 struct page *page;
1165
1166 ptl = pmd_trans_huge_lock(pmd, vma);
1167 if (ptl) {
1168 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
1169 clear_soft_dirty_pmd(vma, addr, pmd);
1170 goto out;
1171 }
1172
1173 if (!pmd_present(*pmd))
1174 goto out;
1175
1176 page = pmd_page(*pmd);
1177
1178 /* Clear accessed and referenced bits. */
1179 pmdp_test_and_clear_young(vma, addr, pmd);
1180 test_and_clear_page_young(page);
1181 ClearPageReferenced(page);
1182out:
1183 spin_unlock(ptl);
1184 return 0;
1185 }
1186
1187 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
1188 if (!pte) {
1189 walk->action = ACTION_AGAIN;
1190 return 0;
1191 }
1192 for (; addr != end; pte++, addr += PAGE_SIZE) {
1193 ptent = ptep_get(pte);
1194
1195 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
1196 clear_soft_dirty(vma, addr, pte);
1197 continue;
1198 }
1199
1200 if (!pte_present(ptent))
1201 continue;
1202
1203 page = vm_normal_page(vma, addr, ptent);
1204 if (!page)
1205 continue;
1206
1207 /* Clear accessed and referenced bits. */
1208 ptep_test_and_clear_young(vma, addr, pte);
1209 test_and_clear_page_young(page);
1210 ClearPageReferenced(page);
1211 }
1212 pte_unmap_unlock(pte - 1, ptl);
1213 cond_resched();
1214 return 0;
1215}
1216
1217static int clear_refs_test_walk(unsigned long start, unsigned long end,
1218 struct mm_walk *walk)
1219{
1220 struct clear_refs_private *cp = walk->private;
1221 struct vm_area_struct *vma = walk->vma;
1222
1223 if (vma->vm_flags & VM_PFNMAP)
1224 return 1;
1225
1226 /*
1227 * Writing 1 to /proc/pid/clear_refs affects all pages.
1228 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages.
1229 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages.
1230 * Writing 4 to /proc/pid/clear_refs affects all pages.
1231 */
1232 if (cp->type == CLEAR_REFS_ANON && vma->vm_file)
1233 return 1;
1234 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file)
1235 return 1;
1236 return 0;
1237}
1238
1239static const struct mm_walk_ops clear_refs_walk_ops = {
1240 .pmd_entry = clear_refs_pte_range,
1241 .test_walk = clear_refs_test_walk,
1242 .walk_lock = PGWALK_WRLOCK,
1243};
1244
1245static ssize_t clear_refs_write(struct file *file, const char __user *buf,
1246 size_t count, loff_t *ppos)
1247{
1248 struct task_struct *task;
1249 char buffer[PROC_NUMBUF] = {};
1250 struct mm_struct *mm;
1251 struct vm_area_struct *vma;
1252 enum clear_refs_types type;
1253 int itype;
1254 int rv;
1255
1256 if (count > sizeof(buffer) - 1)
1257 count = sizeof(buffer) - 1;
1258 if (copy_from_user(buffer, buf, count))
1259 return -EFAULT;
1260 rv = kstrtoint(strstrip(buffer), 10, &itype);
1261 if (rv < 0)
1262 return rv;
1263 type = (enum clear_refs_types)itype;
1264 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
1265 return -EINVAL;
1266
1267 task = get_proc_task(file_inode(file));
1268 if (!task)
1269 return -ESRCH;
1270 mm = get_task_mm(task);
1271 if (mm) {
1272 VMA_ITERATOR(vmi, mm, 0);
1273 struct mmu_notifier_range range;
1274 struct clear_refs_private cp = {
1275 .type = type,
1276 };
1277
1278 if (mmap_write_lock_killable(mm)) {
1279 count = -EINTR;
1280 goto out_mm;
1281 }
1282 if (type == CLEAR_REFS_MM_HIWATER_RSS) {
1283 /*
1284 * Writing 5 to /proc/pid/clear_refs resets the peak
1285 * resident set size to this mm's current rss value.
1286 */
1287 reset_mm_hiwater_rss(mm);
1288 goto out_unlock;
1289 }
1290
1291 if (type == CLEAR_REFS_SOFT_DIRTY) {
1292 for_each_vma(vmi, vma) {
1293 if (!(vma->vm_flags & VM_SOFTDIRTY))
1294 continue;
1295 vm_flags_clear(vma, VM_SOFTDIRTY);
1296 vma_set_page_prot(vma);
1297 }
1298
1299 inc_tlb_flush_pending(mm);
1300 mmu_notifier_range_init(&range, MMU_NOTIFY_SOFT_DIRTY,
1301 0, mm, 0, -1UL);
1302 mmu_notifier_invalidate_range_start(&range);
1303 }
1304 walk_page_range(mm, 0, -1, &clear_refs_walk_ops, &cp);
1305 if (type == CLEAR_REFS_SOFT_DIRTY) {
1306 mmu_notifier_invalidate_range_end(&range);
1307 flush_tlb_mm(mm);
1308 dec_tlb_flush_pending(mm);
1309 }
1310out_unlock:
1311 mmap_write_unlock(mm);
1312out_mm:
1313 mmput(mm);
1314 }
1315 put_task_struct(task);
1316
1317 return count;
1318}
1319
1320const struct file_operations proc_clear_refs_operations = {
1321 .write = clear_refs_write,
1322 .llseek = noop_llseek,
1323};
1324
1325typedef struct {
1326 u64 pme;
1327} pagemap_entry_t;
1328
1329struct pagemapread {
1330 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */
1331 pagemap_entry_t *buffer;
1332 bool show_pfn;
1333};
1334
1335#define PAGEMAP_WALK_SIZE (PMD_SIZE)
1336#define PAGEMAP_WALK_MASK (PMD_MASK)
1337
1338#define PM_ENTRY_BYTES sizeof(pagemap_entry_t)
1339#define PM_PFRAME_BITS 55
1340#define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0)
1341#define PM_SOFT_DIRTY BIT_ULL(55)
1342#define PM_MMAP_EXCLUSIVE BIT_ULL(56)
1343#define PM_UFFD_WP BIT_ULL(57)
1344#define PM_FILE BIT_ULL(61)
1345#define PM_SWAP BIT_ULL(62)
1346#define PM_PRESENT BIT_ULL(63)
1347
1348#define PM_END_OF_BUFFER 1
1349
1350static inline pagemap_entry_t make_pme(u64 frame, u64 flags)
1351{
1352 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags };
1353}
1354
1355static int add_to_pagemap(pagemap_entry_t *pme, struct pagemapread *pm)
1356{
1357 pm->buffer[pm->pos++] = *pme;
1358 if (pm->pos >= pm->len)
1359 return PM_END_OF_BUFFER;
1360 return 0;
1361}
1362
1363static int pagemap_pte_hole(unsigned long start, unsigned long end,
1364 __always_unused int depth, struct mm_walk *walk)
1365{
1366 struct pagemapread *pm = walk->private;
1367 unsigned long addr = start;
1368 int err = 0;
1369
1370 while (addr < end) {
1371 struct vm_area_struct *vma = find_vma(walk->mm, addr);
1372 pagemap_entry_t pme = make_pme(0, 0);
1373 /* End of address space hole, which we mark as non-present. */
1374 unsigned long hole_end;
1375
1376 if (vma)
1377 hole_end = min(end, vma->vm_start);
1378 else
1379 hole_end = end;
1380
1381 for (; addr < hole_end; addr += PAGE_SIZE) {
1382 err = add_to_pagemap(&pme, pm);
1383 if (err)
1384 goto out;
1385 }
1386
1387 if (!vma)
1388 break;
1389
1390 /* Addresses in the VMA. */
1391 if (vma->vm_flags & VM_SOFTDIRTY)
1392 pme = make_pme(0, PM_SOFT_DIRTY);
1393 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) {
1394 err = add_to_pagemap(&pme, pm);
1395 if (err)
1396 goto out;
1397 }
1398 }
1399out:
1400 return err;
1401}
1402
1403static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm,
1404 struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1405{
1406 u64 frame = 0, flags = 0;
1407 struct page *page = NULL;
1408 bool migration = false;
1409
1410 if (pte_present(pte)) {
1411 if (pm->show_pfn)
1412 frame = pte_pfn(pte);
1413 flags |= PM_PRESENT;
1414 page = vm_normal_page(vma, addr, pte);
1415 if (pte_soft_dirty(pte))
1416 flags |= PM_SOFT_DIRTY;
1417 if (pte_uffd_wp(pte))
1418 flags |= PM_UFFD_WP;
1419 } else if (is_swap_pte(pte)) {
1420 swp_entry_t entry;
1421 if (pte_swp_soft_dirty(pte))
1422 flags |= PM_SOFT_DIRTY;
1423 if (pte_swp_uffd_wp(pte))
1424 flags |= PM_UFFD_WP;
1425 entry = pte_to_swp_entry(pte);
1426 if (pm->show_pfn) {
1427 pgoff_t offset;
1428 /*
1429 * For PFN swap offsets, keeping the offset field
1430 * to be PFN only to be compatible with old smaps.
1431 */
1432 if (is_pfn_swap_entry(entry))
1433 offset = swp_offset_pfn(entry);
1434 else
1435 offset = swp_offset(entry);
1436 frame = swp_type(entry) |
1437 (offset << MAX_SWAPFILES_SHIFT);
1438 }
1439 flags |= PM_SWAP;
1440 migration = is_migration_entry(entry);
1441 if (is_pfn_swap_entry(entry))
1442 page = pfn_swap_entry_to_page(entry);
1443 if (pte_marker_entry_uffd_wp(entry))
1444 flags |= PM_UFFD_WP;
1445 }
1446
1447 if (page && !PageAnon(page))
1448 flags |= PM_FILE;
1449 if (page && !migration && page_mapcount(page) == 1)
1450 flags |= PM_MMAP_EXCLUSIVE;
1451 if (vma->vm_flags & VM_SOFTDIRTY)
1452 flags |= PM_SOFT_DIRTY;
1453
1454 return make_pme(frame, flags);
1455}
1456
1457static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
1458 struct mm_walk *walk)
1459{
1460 struct vm_area_struct *vma = walk->vma;
1461 struct pagemapread *pm = walk->private;
1462 spinlock_t *ptl;
1463 pte_t *pte, *orig_pte;
1464 int err = 0;
1465#ifdef CONFIG_TRANSPARENT_HUGEPAGE
1466 bool migration = false;
1467
1468 ptl = pmd_trans_huge_lock(pmdp, vma);
1469 if (ptl) {
1470 u64 flags = 0, frame = 0;
1471 pmd_t pmd = *pmdp;
1472 struct page *page = NULL;
1473
1474 if (vma->vm_flags & VM_SOFTDIRTY)
1475 flags |= PM_SOFT_DIRTY;
1476
1477 if (pmd_present(pmd)) {
1478 page = pmd_page(pmd);
1479
1480 flags |= PM_PRESENT;
1481 if (pmd_soft_dirty(pmd))
1482 flags |= PM_SOFT_DIRTY;
1483 if (pmd_uffd_wp(pmd))
1484 flags |= PM_UFFD_WP;
1485 if (pm->show_pfn)
1486 frame = pmd_pfn(pmd) +
1487 ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1488 }
1489#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
1490 else if (is_swap_pmd(pmd)) {
1491 swp_entry_t entry = pmd_to_swp_entry(pmd);
1492 unsigned long offset;
1493
1494 if (pm->show_pfn) {
1495 if (is_pfn_swap_entry(entry))
1496 offset = swp_offset_pfn(entry);
1497 else
1498 offset = swp_offset(entry);
1499 offset = offset +
1500 ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1501 frame = swp_type(entry) |
1502 (offset << MAX_SWAPFILES_SHIFT);
1503 }
1504 flags |= PM_SWAP;
1505 if (pmd_swp_soft_dirty(pmd))
1506 flags |= PM_SOFT_DIRTY;
1507 if (pmd_swp_uffd_wp(pmd))
1508 flags |= PM_UFFD_WP;
1509 VM_BUG_ON(!is_pmd_migration_entry(pmd));
1510 migration = is_migration_entry(entry);
1511 page = pfn_swap_entry_to_page(entry);
1512 }
1513#endif
1514
1515 if (page && !migration && page_mapcount(page) == 1)
1516 flags |= PM_MMAP_EXCLUSIVE;
1517
1518 for (; addr != end; addr += PAGE_SIZE) {
1519 pagemap_entry_t pme = make_pme(frame, flags);
1520
1521 err = add_to_pagemap(&pme, pm);
1522 if (err)
1523 break;
1524 if (pm->show_pfn) {
1525 if (flags & PM_PRESENT)
1526 frame++;
1527 else if (flags & PM_SWAP)
1528 frame += (1 << MAX_SWAPFILES_SHIFT);
1529 }
1530 }
1531 spin_unlock(ptl);
1532 return err;
1533 }
1534#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1535
1536 /*
1537 * We can assume that @vma always points to a valid one and @end never
1538 * goes beyond vma->vm_end.
1539 */
1540 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl);
1541 if (!pte) {
1542 walk->action = ACTION_AGAIN;
1543 return err;
1544 }
1545 for (; addr < end; pte++, addr += PAGE_SIZE) {
1546 pagemap_entry_t pme;
1547
1548 pme = pte_to_pagemap_entry(pm, vma, addr, ptep_get(pte));
1549 err = add_to_pagemap(&pme, pm);
1550 if (err)
1551 break;
1552 }
1553 pte_unmap_unlock(orig_pte, ptl);
1554
1555 cond_resched();
1556
1557 return err;
1558}
1559
1560#ifdef CONFIG_HUGETLB_PAGE
1561/* This function walks within one hugetlb entry in the single call */
1562static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask,
1563 unsigned long addr, unsigned long end,
1564 struct mm_walk *walk)
1565{
1566 struct pagemapread *pm = walk->private;
1567 struct vm_area_struct *vma = walk->vma;
1568 u64 flags = 0, frame = 0;
1569 int err = 0;
1570 pte_t pte;
1571
1572 if (vma->vm_flags & VM_SOFTDIRTY)
1573 flags |= PM_SOFT_DIRTY;
1574
1575 pte = huge_ptep_get(ptep);
1576 if (pte_present(pte)) {
1577 struct page *page = pte_page(pte);
1578
1579 if (!PageAnon(page))
1580 flags |= PM_FILE;
1581
1582 if (page_mapcount(page) == 1)
1583 flags |= PM_MMAP_EXCLUSIVE;
1584
1585 if (huge_pte_uffd_wp(pte))
1586 flags |= PM_UFFD_WP;
1587
1588 flags |= PM_PRESENT;
1589 if (pm->show_pfn)
1590 frame = pte_pfn(pte) +
1591 ((addr & ~hmask) >> PAGE_SHIFT);
1592 } else if (pte_swp_uffd_wp_any(pte)) {
1593 flags |= PM_UFFD_WP;
1594 }
1595
1596 for (; addr != end; addr += PAGE_SIZE) {
1597 pagemap_entry_t pme = make_pme(frame, flags);
1598
1599 err = add_to_pagemap(&pme, pm);
1600 if (err)
1601 return err;
1602 if (pm->show_pfn && (flags & PM_PRESENT))
1603 frame++;
1604 }
1605
1606 cond_resched();
1607
1608 return err;
1609}
1610#else
1611#define pagemap_hugetlb_range NULL
1612#endif /* HUGETLB_PAGE */
1613
1614static const struct mm_walk_ops pagemap_ops = {
1615 .pmd_entry = pagemap_pmd_range,
1616 .pte_hole = pagemap_pte_hole,
1617 .hugetlb_entry = pagemap_hugetlb_range,
1618 .walk_lock = PGWALK_RDLOCK,
1619};
1620
1621/*
1622 * /proc/pid/pagemap - an array mapping virtual pages to pfns
1623 *
1624 * For each page in the address space, this file contains one 64-bit entry
1625 * consisting of the following:
1626 *
1627 * Bits 0-54 page frame number (PFN) if present
1628 * Bits 0-4 swap type if swapped
1629 * Bits 5-54 swap offset if swapped
1630 * Bit 55 pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst)
1631 * Bit 56 page exclusively mapped
1632 * Bit 57 pte is uffd-wp write-protected
1633 * Bits 58-60 zero
1634 * Bit 61 page is file-page or shared-anon
1635 * Bit 62 page swapped
1636 * Bit 63 page present
1637 *
1638 * If the page is not present but in swap, then the PFN contains an
1639 * encoding of the swap file number and the page's offset into the
1640 * swap. Unmapped pages return a null PFN. This allows determining
1641 * precisely which pages are mapped (or in swap) and comparing mapped
1642 * pages between processes.
1643 *
1644 * Efficient users of this interface will use /proc/pid/maps to
1645 * determine which areas of memory are actually mapped and llseek to
1646 * skip over unmapped regions.
1647 */
1648static ssize_t pagemap_read(struct file *file, char __user *buf,
1649 size_t count, loff_t *ppos)
1650{
1651 struct mm_struct *mm = file->private_data;
1652 struct pagemapread pm;
1653 unsigned long src;
1654 unsigned long svpfn;
1655 unsigned long start_vaddr;
1656 unsigned long end_vaddr;
1657 int ret = 0, copied = 0;
1658
1659 if (!mm || !mmget_not_zero(mm))
1660 goto out;
1661
1662 ret = -EINVAL;
1663 /* file position must be aligned */
1664 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
1665 goto out_mm;
1666
1667 ret = 0;
1668 if (!count)
1669 goto out_mm;
1670
1671 /* do not disclose physical addresses: attack vector */
1672 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN);
1673
1674 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
1675 pm.buffer = kmalloc_array(pm.len, PM_ENTRY_BYTES, GFP_KERNEL);
1676 ret = -ENOMEM;
1677 if (!pm.buffer)
1678 goto out_mm;
1679
1680 src = *ppos;
1681 svpfn = src / PM_ENTRY_BYTES;
1682 end_vaddr = mm->task_size;
1683
1684 /* watch out for wraparound */
1685 start_vaddr = end_vaddr;
1686 if (svpfn <= (ULONG_MAX >> PAGE_SHIFT)) {
1687 unsigned long end;
1688
1689 ret = mmap_read_lock_killable(mm);
1690 if (ret)
1691 goto out_free;
1692 start_vaddr = untagged_addr_remote(mm, svpfn << PAGE_SHIFT);
1693 mmap_read_unlock(mm);
1694
1695 end = start_vaddr + ((count / PM_ENTRY_BYTES) << PAGE_SHIFT);
1696 if (end >= start_vaddr && end < mm->task_size)
1697 end_vaddr = end;
1698 }
1699
1700 /* Ensure the address is inside the task */
1701 if (start_vaddr > mm->task_size)
1702 start_vaddr = end_vaddr;
1703
1704 ret = 0;
1705 while (count && (start_vaddr < end_vaddr)) {
1706 int len;
1707 unsigned long end;
1708
1709 pm.pos = 0;
1710 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
1711 /* overflow ? */
1712 if (end < start_vaddr || end > end_vaddr)
1713 end = end_vaddr;
1714 ret = mmap_read_lock_killable(mm);
1715 if (ret)
1716 goto out_free;
1717 ret = walk_page_range(mm, start_vaddr, end, &pagemap_ops, &pm);
1718 mmap_read_unlock(mm);
1719 start_vaddr = end;
1720
1721 len = min(count, PM_ENTRY_BYTES * pm.pos);
1722 if (copy_to_user(buf, pm.buffer, len)) {
1723 ret = -EFAULT;
1724 goto out_free;
1725 }
1726 copied += len;
1727 buf += len;
1728 count -= len;
1729 }
1730 *ppos += copied;
1731 if (!ret || ret == PM_END_OF_BUFFER)
1732 ret = copied;
1733
1734out_free:
1735 kfree(pm.buffer);
1736out_mm:
1737 mmput(mm);
1738out:
1739 return ret;
1740}
1741
1742static int pagemap_open(struct inode *inode, struct file *file)
1743{
1744 struct mm_struct *mm;
1745
1746 mm = proc_mem_open(inode, PTRACE_MODE_READ);
1747 if (IS_ERR(mm))
1748 return PTR_ERR(mm);
1749 file->private_data = mm;
1750 return 0;
1751}
1752
1753static int pagemap_release(struct inode *inode, struct file *file)
1754{
1755 struct mm_struct *mm = file->private_data;
1756
1757 if (mm)
1758 mmdrop(mm);
1759 return 0;
1760}
1761
1762#define PM_SCAN_CATEGORIES (PAGE_IS_WPALLOWED | PAGE_IS_WRITTEN | \
1763 PAGE_IS_FILE | PAGE_IS_PRESENT | \
1764 PAGE_IS_SWAPPED | PAGE_IS_PFNZERO | \
1765 PAGE_IS_HUGE | PAGE_IS_SOFT_DIRTY)
1766#define PM_SCAN_FLAGS (PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC)
1767
1768struct pagemap_scan_private {
1769 struct pm_scan_arg arg;
1770 unsigned long masks_of_interest, cur_vma_category;
1771 struct page_region *vec_buf;
1772 unsigned long vec_buf_len, vec_buf_index, found_pages;
1773 struct page_region __user *vec_out;
1774};
1775
1776static unsigned long pagemap_page_category(struct pagemap_scan_private *p,
1777 struct vm_area_struct *vma,
1778 unsigned long addr, pte_t pte)
1779{
1780 unsigned long categories = 0;
1781
1782 if (pte_present(pte)) {
1783 struct page *page;
1784
1785 categories |= PAGE_IS_PRESENT;
1786 if (!pte_uffd_wp(pte))
1787 categories |= PAGE_IS_WRITTEN;
1788
1789 if (p->masks_of_interest & PAGE_IS_FILE) {
1790 page = vm_normal_page(vma, addr, pte);
1791 if (page && !PageAnon(page))
1792 categories |= PAGE_IS_FILE;
1793 }
1794
1795 if (is_zero_pfn(pte_pfn(pte)))
1796 categories |= PAGE_IS_PFNZERO;
1797 if (pte_soft_dirty(pte))
1798 categories |= PAGE_IS_SOFT_DIRTY;
1799 } else if (is_swap_pte(pte)) {
1800 swp_entry_t swp;
1801
1802 categories |= PAGE_IS_SWAPPED;
1803 if (!pte_swp_uffd_wp_any(pte))
1804 categories |= PAGE_IS_WRITTEN;
1805
1806 if (p->masks_of_interest & PAGE_IS_FILE) {
1807 swp = pte_to_swp_entry(pte);
1808 if (is_pfn_swap_entry(swp) &&
1809 !folio_test_anon(pfn_swap_entry_folio(swp)))
1810 categories |= PAGE_IS_FILE;
1811 }
1812 if (pte_swp_soft_dirty(pte))
1813 categories |= PAGE_IS_SOFT_DIRTY;
1814 }
1815
1816 return categories;
1817}
1818
1819static void make_uffd_wp_pte(struct vm_area_struct *vma,
1820 unsigned long addr, pte_t *pte, pte_t ptent)
1821{
1822 if (pte_present(ptent)) {
1823 pte_t old_pte;
1824
1825 old_pte = ptep_modify_prot_start(vma, addr, pte);
1826 ptent = pte_mkuffd_wp(old_pte);
1827 ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent);
1828 } else if (is_swap_pte(ptent)) {
1829 ptent = pte_swp_mkuffd_wp(ptent);
1830 set_pte_at(vma->vm_mm, addr, pte, ptent);
1831 } else {
1832 set_pte_at(vma->vm_mm, addr, pte,
1833 make_pte_marker(PTE_MARKER_UFFD_WP));
1834 }
1835}
1836
1837#ifdef CONFIG_TRANSPARENT_HUGEPAGE
1838static unsigned long pagemap_thp_category(struct pagemap_scan_private *p,
1839 struct vm_area_struct *vma,
1840 unsigned long addr, pmd_t pmd)
1841{
1842 unsigned long categories = PAGE_IS_HUGE;
1843
1844 if (pmd_present(pmd)) {
1845 struct page *page;
1846
1847 categories |= PAGE_IS_PRESENT;
1848 if (!pmd_uffd_wp(pmd))
1849 categories |= PAGE_IS_WRITTEN;
1850
1851 if (p->masks_of_interest & PAGE_IS_FILE) {
1852 page = vm_normal_page_pmd(vma, addr, pmd);
1853 if (page && !PageAnon(page))
1854 categories |= PAGE_IS_FILE;
1855 }
1856
1857 if (is_zero_pfn(pmd_pfn(pmd)))
1858 categories |= PAGE_IS_PFNZERO;
1859 if (pmd_soft_dirty(pmd))
1860 categories |= PAGE_IS_SOFT_DIRTY;
1861 } else if (is_swap_pmd(pmd)) {
1862 swp_entry_t swp;
1863
1864 categories |= PAGE_IS_SWAPPED;
1865 if (!pmd_swp_uffd_wp(pmd))
1866 categories |= PAGE_IS_WRITTEN;
1867 if (pmd_swp_soft_dirty(pmd))
1868 categories |= PAGE_IS_SOFT_DIRTY;
1869
1870 if (p->masks_of_interest & PAGE_IS_FILE) {
1871 swp = pmd_to_swp_entry(pmd);
1872 if (is_pfn_swap_entry(swp) &&
1873 !folio_test_anon(pfn_swap_entry_folio(swp)))
1874 categories |= PAGE_IS_FILE;
1875 }
1876 }
1877
1878 return categories;
1879}
1880
1881static void make_uffd_wp_pmd(struct vm_area_struct *vma,
1882 unsigned long addr, pmd_t *pmdp)
1883{
1884 pmd_t old, pmd = *pmdp;
1885
1886 if (pmd_present(pmd)) {
1887 old = pmdp_invalidate_ad(vma, addr, pmdp);
1888 pmd = pmd_mkuffd_wp(old);
1889 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
1890 } else if (is_migration_entry(pmd_to_swp_entry(pmd))) {
1891 pmd = pmd_swp_mkuffd_wp(pmd);
1892 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
1893 }
1894}
1895#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1896
1897#ifdef CONFIG_HUGETLB_PAGE
1898static unsigned long pagemap_hugetlb_category(pte_t pte)
1899{
1900 unsigned long categories = PAGE_IS_HUGE;
1901
1902 /*
1903 * According to pagemap_hugetlb_range(), file-backed HugeTLB
1904 * page cannot be swapped. So PAGE_IS_FILE is not checked for
1905 * swapped pages.
1906 */
1907 if (pte_present(pte)) {
1908 categories |= PAGE_IS_PRESENT;
1909 if (!huge_pte_uffd_wp(pte))
1910 categories |= PAGE_IS_WRITTEN;
1911 if (!PageAnon(pte_page(pte)))
1912 categories |= PAGE_IS_FILE;
1913 if (is_zero_pfn(pte_pfn(pte)))
1914 categories |= PAGE_IS_PFNZERO;
1915 if (pte_soft_dirty(pte))
1916 categories |= PAGE_IS_SOFT_DIRTY;
1917 } else if (is_swap_pte(pte)) {
1918 categories |= PAGE_IS_SWAPPED;
1919 if (!pte_swp_uffd_wp_any(pte))
1920 categories |= PAGE_IS_WRITTEN;
1921 if (pte_swp_soft_dirty(pte))
1922 categories |= PAGE_IS_SOFT_DIRTY;
1923 }
1924
1925 return categories;
1926}
1927
1928static void make_uffd_wp_huge_pte(struct vm_area_struct *vma,
1929 unsigned long addr, pte_t *ptep,
1930 pte_t ptent)
1931{
1932 unsigned long psize;
1933
1934 if (is_hugetlb_entry_hwpoisoned(ptent) || is_pte_marker(ptent))
1935 return;
1936
1937 psize = huge_page_size(hstate_vma(vma));
1938
1939 if (is_hugetlb_entry_migration(ptent))
1940 set_huge_pte_at(vma->vm_mm, addr, ptep,
1941 pte_swp_mkuffd_wp(ptent), psize);
1942 else if (!huge_pte_none(ptent))
1943 huge_ptep_modify_prot_commit(vma, addr, ptep, ptent,
1944 huge_pte_mkuffd_wp(ptent));
1945 else
1946 set_huge_pte_at(vma->vm_mm, addr, ptep,
1947 make_pte_marker(PTE_MARKER_UFFD_WP), psize);
1948}
1949#endif /* CONFIG_HUGETLB_PAGE */
1950
1951#if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLB_PAGE)
1952static void pagemap_scan_backout_range(struct pagemap_scan_private *p,
1953 unsigned long addr, unsigned long end)
1954{
1955 struct page_region *cur_buf = &p->vec_buf[p->vec_buf_index];
1956
1957 if (cur_buf->start != addr)
1958 cur_buf->end = addr;
1959 else
1960 cur_buf->start = cur_buf->end = 0;
1961
1962 p->found_pages -= (end - addr) / PAGE_SIZE;
1963}
1964#endif
1965
1966static bool pagemap_scan_is_interesting_page(unsigned long categories,
1967 const struct pagemap_scan_private *p)
1968{
1969 categories ^= p->arg.category_inverted;
1970 if ((categories & p->arg.category_mask) != p->arg.category_mask)
1971 return false;
1972 if (p->arg.category_anyof_mask && !(categories & p->arg.category_anyof_mask))
1973 return false;
1974
1975 return true;
1976}
1977
1978static bool pagemap_scan_is_interesting_vma(unsigned long categories,
1979 const struct pagemap_scan_private *p)
1980{
1981 unsigned long required = p->arg.category_mask & PAGE_IS_WPALLOWED;
1982
1983 categories ^= p->arg.category_inverted;
1984 if ((categories & required) != required)
1985 return false;
1986
1987 return true;
1988}
1989
1990static int pagemap_scan_test_walk(unsigned long start, unsigned long end,
1991 struct mm_walk *walk)
1992{
1993 struct pagemap_scan_private *p = walk->private;
1994 struct vm_area_struct *vma = walk->vma;
1995 unsigned long vma_category = 0;
1996 bool wp_allowed = userfaultfd_wp_async(vma) &&
1997 userfaultfd_wp_use_markers(vma);
1998
1999 if (!wp_allowed) {
2000 /* User requested explicit failure over wp-async capability */
2001 if (p->arg.flags & PM_SCAN_CHECK_WPASYNC)
2002 return -EPERM;
2003 /*
2004 * User requires wr-protect, and allows silently skipping
2005 * unsupported vmas.
2006 */
2007 if (p->arg.flags & PM_SCAN_WP_MATCHING)
2008 return 1;
2009 /*
2010 * Then the request doesn't involve wr-protects at all,
2011 * fall through to the rest checks, and allow vma walk.
2012 */
2013 }
2014
2015 if (vma->vm_flags & VM_PFNMAP)
2016 return 1;
2017
2018 if (wp_allowed)
2019 vma_category |= PAGE_IS_WPALLOWED;
2020
2021 if (vma->vm_flags & VM_SOFTDIRTY)
2022 vma_category |= PAGE_IS_SOFT_DIRTY;
2023
2024 if (!pagemap_scan_is_interesting_vma(vma_category, p))
2025 return 1;
2026
2027 p->cur_vma_category = vma_category;
2028
2029 return 0;
2030}
2031
2032static bool pagemap_scan_push_range(unsigned long categories,
2033 struct pagemap_scan_private *p,
2034 unsigned long addr, unsigned long end)
2035{
2036 struct page_region *cur_buf = &p->vec_buf[p->vec_buf_index];
2037
2038 /*
2039 * When there is no output buffer provided at all, the sentinel values
2040 * won't match here. There is no other way for `cur_buf->end` to be
2041 * non-zero other than it being non-empty.
2042 */
2043 if (addr == cur_buf->end && categories == cur_buf->categories) {
2044 cur_buf->end = end;
2045 return true;
2046 }
2047
2048 if (cur_buf->end) {
2049 if (p->vec_buf_index >= p->vec_buf_len - 1)
2050 return false;
2051
2052 cur_buf = &p->vec_buf[++p->vec_buf_index];
2053 }
2054
2055 cur_buf->start = addr;
2056 cur_buf->end = end;
2057 cur_buf->categories = categories;
2058
2059 return true;
2060}
2061
2062static int pagemap_scan_output(unsigned long categories,
2063 struct pagemap_scan_private *p,
2064 unsigned long addr, unsigned long *end)
2065{
2066 unsigned long n_pages, total_pages;
2067 int ret = 0;
2068
2069 if (!p->vec_buf)
2070 return 0;
2071
2072 categories &= p->arg.return_mask;
2073
2074 n_pages = (*end - addr) / PAGE_SIZE;
2075 if (check_add_overflow(p->found_pages, n_pages, &total_pages) ||
2076 total_pages > p->arg.max_pages) {
2077 size_t n_too_much = total_pages - p->arg.max_pages;
2078 *end -= n_too_much * PAGE_SIZE;
2079 n_pages -= n_too_much;
2080 ret = -ENOSPC;
2081 }
2082
2083 if (!pagemap_scan_push_range(categories, p, addr, *end)) {
2084 *end = addr;
2085 n_pages = 0;
2086 ret = -ENOSPC;
2087 }
2088
2089 p->found_pages += n_pages;
2090 if (ret)
2091 p->arg.walk_end = *end;
2092
2093 return ret;
2094}
2095
2096static int pagemap_scan_thp_entry(pmd_t *pmd, unsigned long start,
2097 unsigned long end, struct mm_walk *walk)
2098{
2099#ifdef CONFIG_TRANSPARENT_HUGEPAGE
2100 struct pagemap_scan_private *p = walk->private;
2101 struct vm_area_struct *vma = walk->vma;
2102 unsigned long categories;
2103 spinlock_t *ptl;
2104 int ret = 0;
2105
2106 ptl = pmd_trans_huge_lock(pmd, vma);
2107 if (!ptl)
2108 return -ENOENT;
2109
2110 categories = p->cur_vma_category |
2111 pagemap_thp_category(p, vma, start, *pmd);
2112
2113 if (!pagemap_scan_is_interesting_page(categories, p))
2114 goto out_unlock;
2115
2116 ret = pagemap_scan_output(categories, p, start, &end);
2117 if (start == end)
2118 goto out_unlock;
2119
2120 if (~p->arg.flags & PM_SCAN_WP_MATCHING)
2121 goto out_unlock;
2122 if (~categories & PAGE_IS_WRITTEN)
2123 goto out_unlock;
2124
2125 /*
2126 * Break huge page into small pages if the WP operation
2127 * needs to be performed on a portion of the huge page.
2128 */
2129 if (end != start + HPAGE_SIZE) {
2130 spin_unlock(ptl);
2131 split_huge_pmd(vma, pmd, start);
2132 pagemap_scan_backout_range(p, start, end);
2133 /* Report as if there was no THP */
2134 return -ENOENT;
2135 }
2136
2137 make_uffd_wp_pmd(vma, start, pmd);
2138 flush_tlb_range(vma, start, end);
2139out_unlock:
2140 spin_unlock(ptl);
2141 return ret;
2142#else /* !CONFIG_TRANSPARENT_HUGEPAGE */
2143 return -ENOENT;
2144#endif
2145}
2146
2147static int pagemap_scan_pmd_entry(pmd_t *pmd, unsigned long start,
2148 unsigned long end, struct mm_walk *walk)
2149{
2150 struct pagemap_scan_private *p = walk->private;
2151 struct vm_area_struct *vma = walk->vma;
2152 unsigned long addr, flush_end = 0;
2153 pte_t *pte, *start_pte;
2154 spinlock_t *ptl;
2155 int ret;
2156
2157 arch_enter_lazy_mmu_mode();
2158
2159 ret = pagemap_scan_thp_entry(pmd, start, end, walk);
2160 if (ret != -ENOENT) {
2161 arch_leave_lazy_mmu_mode();
2162 return ret;
2163 }
2164
2165 ret = 0;
2166 start_pte = pte = pte_offset_map_lock(vma->vm_mm, pmd, start, &ptl);
2167 if (!pte) {
2168 arch_leave_lazy_mmu_mode();
2169 walk->action = ACTION_AGAIN;
2170 return 0;
2171 }
2172
2173 if ((p->arg.flags & PM_SCAN_WP_MATCHING) && !p->vec_out) {
2174 /* Fast path for performing exclusive WP */
2175 for (addr = start; addr != end; pte++, addr += PAGE_SIZE) {
2176 pte_t ptent = ptep_get(pte);
2177
2178 if ((pte_present(ptent) && pte_uffd_wp(ptent)) ||
2179 pte_swp_uffd_wp_any(ptent))
2180 continue;
2181 make_uffd_wp_pte(vma, addr, pte, ptent);
2182 if (!flush_end)
2183 start = addr;
2184 flush_end = addr + PAGE_SIZE;
2185 }
2186 goto flush_and_return;
2187 }
2188
2189 if (!p->arg.category_anyof_mask && !p->arg.category_inverted &&
2190 p->arg.category_mask == PAGE_IS_WRITTEN &&
2191 p->arg.return_mask == PAGE_IS_WRITTEN) {
2192 for (addr = start; addr < end; pte++, addr += PAGE_SIZE) {
2193 unsigned long next = addr + PAGE_SIZE;
2194 pte_t ptent = ptep_get(pte);
2195
2196 if ((pte_present(ptent) && pte_uffd_wp(ptent)) ||
2197 pte_swp_uffd_wp_any(ptent))
2198 continue;
2199 ret = pagemap_scan_output(p->cur_vma_category | PAGE_IS_WRITTEN,
2200 p, addr, &next);
2201 if (next == addr)
2202 break;
2203 if (~p->arg.flags & PM_SCAN_WP_MATCHING)
2204 continue;
2205 make_uffd_wp_pte(vma, addr, pte, ptent);
2206 if (!flush_end)
2207 start = addr;
2208 flush_end = next;
2209 }
2210 goto flush_and_return;
2211 }
2212
2213 for (addr = start; addr != end; pte++, addr += PAGE_SIZE) {
2214 pte_t ptent = ptep_get(pte);
2215 unsigned long categories = p->cur_vma_category |
2216 pagemap_page_category(p, vma, addr, ptent);
2217 unsigned long next = addr + PAGE_SIZE;
2218
2219 if (!pagemap_scan_is_interesting_page(categories, p))
2220 continue;
2221
2222 ret = pagemap_scan_output(categories, p, addr, &next);
2223 if (next == addr)
2224 break;
2225
2226 if (~p->arg.flags & PM_SCAN_WP_MATCHING)
2227 continue;
2228 if (~categories & PAGE_IS_WRITTEN)
2229 continue;
2230
2231 make_uffd_wp_pte(vma, addr, pte, ptent);
2232 if (!flush_end)
2233 start = addr;
2234 flush_end = next;
2235 }
2236
2237flush_and_return:
2238 if (flush_end)
2239 flush_tlb_range(vma, start, addr);
2240
2241 pte_unmap_unlock(start_pte, ptl);
2242 arch_leave_lazy_mmu_mode();
2243
2244 cond_resched();
2245 return ret;
2246}
2247
2248#ifdef CONFIG_HUGETLB_PAGE
2249static int pagemap_scan_hugetlb_entry(pte_t *ptep, unsigned long hmask,
2250 unsigned long start, unsigned long end,
2251 struct mm_walk *walk)
2252{
2253 struct pagemap_scan_private *p = walk->private;
2254 struct vm_area_struct *vma = walk->vma;
2255 unsigned long categories;
2256 spinlock_t *ptl;
2257 int ret = 0;
2258 pte_t pte;
2259
2260 if (~p->arg.flags & PM_SCAN_WP_MATCHING) {
2261 /* Go the short route when not write-protecting pages. */
2262
2263 pte = huge_ptep_get(ptep);
2264 categories = p->cur_vma_category | pagemap_hugetlb_category(pte);
2265
2266 if (!pagemap_scan_is_interesting_page(categories, p))
2267 return 0;
2268
2269 return pagemap_scan_output(categories, p, start, &end);
2270 }
2271
2272 i_mmap_lock_write(vma->vm_file->f_mapping);
2273 ptl = huge_pte_lock(hstate_vma(vma), vma->vm_mm, ptep);
2274
2275 pte = huge_ptep_get(ptep);
2276 categories = p->cur_vma_category | pagemap_hugetlb_category(pte);
2277
2278 if (!pagemap_scan_is_interesting_page(categories, p))
2279 goto out_unlock;
2280
2281 ret = pagemap_scan_output(categories, p, start, &end);
2282 if (start == end)
2283 goto out_unlock;
2284
2285 if (~categories & PAGE_IS_WRITTEN)
2286 goto out_unlock;
2287
2288 if (end != start + HPAGE_SIZE) {
2289 /* Partial HugeTLB page WP isn't possible. */
2290 pagemap_scan_backout_range(p, start, end);
2291 p->arg.walk_end = start;
2292 ret = 0;
2293 goto out_unlock;
2294 }
2295
2296 make_uffd_wp_huge_pte(vma, start, ptep, pte);
2297 flush_hugetlb_tlb_range(vma, start, end);
2298
2299out_unlock:
2300 spin_unlock(ptl);
2301 i_mmap_unlock_write(vma->vm_file->f_mapping);
2302
2303 return ret;
2304}
2305#else
2306#define pagemap_scan_hugetlb_entry NULL
2307#endif
2308
2309static int pagemap_scan_pte_hole(unsigned long addr, unsigned long end,
2310 int depth, struct mm_walk *walk)
2311{
2312 struct pagemap_scan_private *p = walk->private;
2313 struct vm_area_struct *vma = walk->vma;
2314 int ret, err;
2315
2316 if (!vma || !pagemap_scan_is_interesting_page(p->cur_vma_category, p))
2317 return 0;
2318
2319 ret = pagemap_scan_output(p->cur_vma_category, p, addr, &end);
2320 if (addr == end)
2321 return ret;
2322
2323 if (~p->arg.flags & PM_SCAN_WP_MATCHING)
2324 return ret;
2325
2326 err = uffd_wp_range(vma, addr, end - addr, true);
2327 if (err < 0)
2328 ret = err;
2329
2330 return ret;
2331}
2332
2333static const struct mm_walk_ops pagemap_scan_ops = {
2334 .test_walk = pagemap_scan_test_walk,
2335 .pmd_entry = pagemap_scan_pmd_entry,
2336 .pte_hole = pagemap_scan_pte_hole,
2337 .hugetlb_entry = pagemap_scan_hugetlb_entry,
2338};
2339
2340static int pagemap_scan_get_args(struct pm_scan_arg *arg,
2341 unsigned long uarg)
2342{
2343 if (copy_from_user(arg, (void __user *)uarg, sizeof(*arg)))
2344 return -EFAULT;
2345
2346 if (arg->size != sizeof(struct pm_scan_arg))
2347 return -EINVAL;
2348
2349 /* Validate requested features */
2350 if (arg->flags & ~PM_SCAN_FLAGS)
2351 return -EINVAL;
2352 if ((arg->category_inverted | arg->category_mask |
2353 arg->category_anyof_mask | arg->return_mask) & ~PM_SCAN_CATEGORIES)
2354 return -EINVAL;
2355
2356 arg->start = untagged_addr((unsigned long)arg->start);
2357 arg->end = untagged_addr((unsigned long)arg->end);
2358 arg->vec = untagged_addr((unsigned long)arg->vec);
2359
2360 /* Validate memory pointers */
2361 if (!IS_ALIGNED(arg->start, PAGE_SIZE))
2362 return -EINVAL;
2363 if (!access_ok((void __user *)(long)arg->start, arg->end - arg->start))
2364 return -EFAULT;
2365 if (!arg->vec && arg->vec_len)
2366 return -EINVAL;
2367 if (arg->vec && !access_ok((void __user *)(long)arg->vec,
2368 arg->vec_len * sizeof(struct page_region)))
2369 return -EFAULT;
2370
2371 /* Fixup default values */
2372 arg->end = ALIGN(arg->end, PAGE_SIZE);
2373 arg->walk_end = 0;
2374 if (!arg->max_pages)
2375 arg->max_pages = ULONG_MAX;
2376
2377 return 0;
2378}
2379
2380static int pagemap_scan_writeback_args(struct pm_scan_arg *arg,
2381 unsigned long uargl)
2382{
2383 struct pm_scan_arg __user *uarg = (void __user *)uargl;
2384
2385 if (copy_to_user(&uarg->walk_end, &arg->walk_end, sizeof(arg->walk_end)))
2386 return -EFAULT;
2387
2388 return 0;
2389}
2390
2391static int pagemap_scan_init_bounce_buffer(struct pagemap_scan_private *p)
2392{
2393 if (!p->arg.vec_len)
2394 return 0;
2395
2396 p->vec_buf_len = min_t(size_t, PAGEMAP_WALK_SIZE >> PAGE_SHIFT,
2397 p->arg.vec_len);
2398 p->vec_buf = kmalloc_array(p->vec_buf_len, sizeof(*p->vec_buf),
2399 GFP_KERNEL);
2400 if (!p->vec_buf)
2401 return -ENOMEM;
2402
2403 p->vec_buf->start = p->vec_buf->end = 0;
2404 p->vec_out = (struct page_region __user *)(long)p->arg.vec;
2405
2406 return 0;
2407}
2408
2409static long pagemap_scan_flush_buffer(struct pagemap_scan_private *p)
2410{
2411 const struct page_region *buf = p->vec_buf;
2412 long n = p->vec_buf_index;
2413
2414 if (!p->vec_buf)
2415 return 0;
2416
2417 if (buf[n].end != buf[n].start)
2418 n++;
2419
2420 if (!n)
2421 return 0;
2422
2423 if (copy_to_user(p->vec_out, buf, n * sizeof(*buf)))
2424 return -EFAULT;
2425
2426 p->arg.vec_len -= n;
2427 p->vec_out += n;
2428
2429 p->vec_buf_index = 0;
2430 p->vec_buf_len = min_t(size_t, p->vec_buf_len, p->arg.vec_len);
2431 p->vec_buf->start = p->vec_buf->end = 0;
2432
2433 return n;
2434}
2435
2436static long do_pagemap_scan(struct mm_struct *mm, unsigned long uarg)
2437{
2438 struct pagemap_scan_private p = {0};
2439 unsigned long walk_start;
2440 size_t n_ranges_out = 0;
2441 int ret;
2442
2443 ret = pagemap_scan_get_args(&p.arg, uarg);
2444 if (ret)
2445 return ret;
2446
2447 p.masks_of_interest = p.arg.category_mask | p.arg.category_anyof_mask |
2448 p.arg.return_mask;
2449 ret = pagemap_scan_init_bounce_buffer(&p);
2450 if (ret)
2451 return ret;
2452
2453 for (walk_start = p.arg.start; walk_start < p.arg.end;
2454 walk_start = p.arg.walk_end) {
2455 struct mmu_notifier_range range;
2456 long n_out;
2457
2458 if (fatal_signal_pending(current)) {
2459 ret = -EINTR;
2460 break;
2461 }
2462
2463 ret = mmap_read_lock_killable(mm);
2464 if (ret)
2465 break;
2466
2467 /* Protection change for the range is going to happen. */
2468 if (p.arg.flags & PM_SCAN_WP_MATCHING) {
2469 mmu_notifier_range_init(&range, MMU_NOTIFY_PROTECTION_VMA, 0,
2470 mm, walk_start, p.arg.end);
2471 mmu_notifier_invalidate_range_start(&range);
2472 }
2473
2474 ret = walk_page_range(mm, walk_start, p.arg.end,
2475 &pagemap_scan_ops, &p);
2476
2477 if (p.arg.flags & PM_SCAN_WP_MATCHING)
2478 mmu_notifier_invalidate_range_end(&range);
2479
2480 mmap_read_unlock(mm);
2481
2482 n_out = pagemap_scan_flush_buffer(&p);
2483 if (n_out < 0)
2484 ret = n_out;
2485 else
2486 n_ranges_out += n_out;
2487
2488 if (ret != -ENOSPC)
2489 break;
2490
2491 if (p.arg.vec_len == 0 || p.found_pages == p.arg.max_pages)
2492 break;
2493 }
2494
2495 /* ENOSPC signifies early stop (buffer full) from the walk. */
2496 if (!ret || ret == -ENOSPC)
2497 ret = n_ranges_out;
2498
2499 /* The walk_end isn't set when ret is zero */
2500 if (!p.arg.walk_end)
2501 p.arg.walk_end = p.arg.end;
2502 if (pagemap_scan_writeback_args(&p.arg, uarg))
2503 ret = -EFAULT;
2504
2505 kfree(p.vec_buf);
2506 return ret;
2507}
2508
2509static long do_pagemap_cmd(struct file *file, unsigned int cmd,
2510 unsigned long arg)
2511{
2512 struct mm_struct *mm = file->private_data;
2513
2514 switch (cmd) {
2515 case PAGEMAP_SCAN:
2516 return do_pagemap_scan(mm, arg);
2517
2518 default:
2519 return -EINVAL;
2520 }
2521}
2522
2523const struct file_operations proc_pagemap_operations = {
2524 .llseek = mem_lseek, /* borrow this */
2525 .read = pagemap_read,
2526 .open = pagemap_open,
2527 .release = pagemap_release,
2528 .unlocked_ioctl = do_pagemap_cmd,
2529 .compat_ioctl = do_pagemap_cmd,
2530};
2531#endif /* CONFIG_PROC_PAGE_MONITOR */
2532
2533#ifdef CONFIG_NUMA
2534
2535struct numa_maps {
2536 unsigned long pages;
2537 unsigned long anon;
2538 unsigned long active;
2539 unsigned long writeback;
2540 unsigned long mapcount_max;
2541 unsigned long dirty;
2542 unsigned long swapcache;
2543 unsigned long node[MAX_NUMNODES];
2544};
2545
2546struct numa_maps_private {
2547 struct proc_maps_private proc_maps;
2548 struct numa_maps md;
2549};
2550
2551static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
2552 unsigned long nr_pages)
2553{
2554 int count = page_mapcount(page);
2555
2556 md->pages += nr_pages;
2557 if (pte_dirty || PageDirty(page))
2558 md->dirty += nr_pages;
2559
2560 if (PageSwapCache(page))
2561 md->swapcache += nr_pages;
2562
2563 if (PageActive(page) || PageUnevictable(page))
2564 md->active += nr_pages;
2565
2566 if (PageWriteback(page))
2567 md->writeback += nr_pages;
2568
2569 if (PageAnon(page))
2570 md->anon += nr_pages;
2571
2572 if (count > md->mapcount_max)
2573 md->mapcount_max = count;
2574
2575 md->node[page_to_nid(page)] += nr_pages;
2576}
2577
2578static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
2579 unsigned long addr)
2580{
2581 struct page *page;
2582 int nid;
2583
2584 if (!pte_present(pte))
2585 return NULL;
2586
2587 page = vm_normal_page(vma, addr, pte);
2588 if (!page || is_zone_device_page(page))
2589 return NULL;
2590
2591 if (PageReserved(page))
2592 return NULL;
2593
2594 nid = page_to_nid(page);
2595 if (!node_isset(nid, node_states[N_MEMORY]))
2596 return NULL;
2597
2598 return page;
2599}
2600
2601#ifdef CONFIG_TRANSPARENT_HUGEPAGE
2602static struct page *can_gather_numa_stats_pmd(pmd_t pmd,
2603 struct vm_area_struct *vma,
2604 unsigned long addr)
2605{
2606 struct page *page;
2607 int nid;
2608
2609 if (!pmd_present(pmd))
2610 return NULL;
2611
2612 page = vm_normal_page_pmd(vma, addr, pmd);
2613 if (!page)
2614 return NULL;
2615
2616 if (PageReserved(page))
2617 return NULL;
2618
2619 nid = page_to_nid(page);
2620 if (!node_isset(nid, node_states[N_MEMORY]))
2621 return NULL;
2622
2623 return page;
2624}
2625#endif
2626
2627static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
2628 unsigned long end, struct mm_walk *walk)
2629{
2630 struct numa_maps *md = walk->private;
2631 struct vm_area_struct *vma = walk->vma;
2632 spinlock_t *ptl;
2633 pte_t *orig_pte;
2634 pte_t *pte;
2635
2636#ifdef CONFIG_TRANSPARENT_HUGEPAGE
2637 ptl = pmd_trans_huge_lock(pmd, vma);
2638 if (ptl) {
2639 struct page *page;
2640
2641 page = can_gather_numa_stats_pmd(*pmd, vma, addr);
2642 if (page)
2643 gather_stats(page, md, pmd_dirty(*pmd),
2644 HPAGE_PMD_SIZE/PAGE_SIZE);
2645 spin_unlock(ptl);
2646 return 0;
2647 }
2648#endif
2649 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
2650 if (!pte) {
2651 walk->action = ACTION_AGAIN;
2652 return 0;
2653 }
2654 do {
2655 pte_t ptent = ptep_get(pte);
2656 struct page *page = can_gather_numa_stats(ptent, vma, addr);
2657 if (!page)
2658 continue;
2659 gather_stats(page, md, pte_dirty(ptent), 1);
2660
2661 } while (pte++, addr += PAGE_SIZE, addr != end);
2662 pte_unmap_unlock(orig_pte, ptl);
2663 cond_resched();
2664 return 0;
2665}
2666#ifdef CONFIG_HUGETLB_PAGE
2667static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
2668 unsigned long addr, unsigned long end, struct mm_walk *walk)
2669{
2670 pte_t huge_pte = huge_ptep_get(pte);
2671 struct numa_maps *md;
2672 struct page *page;
2673
2674 if (!pte_present(huge_pte))
2675 return 0;
2676
2677 page = pte_page(huge_pte);
2678
2679 md = walk->private;
2680 gather_stats(page, md, pte_dirty(huge_pte), 1);
2681 return 0;
2682}
2683
2684#else
2685static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
2686 unsigned long addr, unsigned long end, struct mm_walk *walk)
2687{
2688 return 0;
2689}
2690#endif
2691
2692static const struct mm_walk_ops show_numa_ops = {
2693 .hugetlb_entry = gather_hugetlb_stats,
2694 .pmd_entry = gather_pte_stats,
2695 .walk_lock = PGWALK_RDLOCK,
2696};
2697
2698/*
2699 * Display pages allocated per node and memory policy via /proc.
2700 */
2701static int show_numa_map(struct seq_file *m, void *v)
2702{
2703 struct numa_maps_private *numa_priv = m->private;
2704 struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
2705 struct vm_area_struct *vma = v;
2706 struct numa_maps *md = &numa_priv->md;
2707 struct file *file = vma->vm_file;
2708 struct mm_struct *mm = vma->vm_mm;
2709 char buffer[64];
2710 struct mempolicy *pol;
2711 pgoff_t ilx;
2712 int nid;
2713
2714 if (!mm)
2715 return 0;
2716
2717 /* Ensure we start with an empty set of numa_maps statistics. */
2718 memset(md, 0, sizeof(*md));
2719
2720 pol = __get_vma_policy(vma, vma->vm_start, &ilx);
2721 if (pol) {
2722 mpol_to_str(buffer, sizeof(buffer), pol);
2723 mpol_cond_put(pol);
2724 } else {
2725 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy);
2726 }
2727
2728 seq_printf(m, "%08lx %s", vma->vm_start, buffer);
2729
2730 if (file) {
2731 seq_puts(m, " file=");
2732 seq_path(m, file_user_path(file), "\n\t= ");
2733 } else if (vma_is_initial_heap(vma)) {
2734 seq_puts(m, " heap");
2735 } else if (vma_is_initial_stack(vma)) {
2736 seq_puts(m, " stack");
2737 }
2738
2739 if (is_vm_hugetlb_page(vma))
2740 seq_puts(m, " huge");
2741
2742 /* mmap_lock is held by m_start */
2743 walk_page_vma(vma, &show_numa_ops, md);
2744
2745 if (!md->pages)
2746 goto out;
2747
2748 if (md->anon)
2749 seq_printf(m, " anon=%lu", md->anon);
2750
2751 if (md->dirty)
2752 seq_printf(m, " dirty=%lu", md->dirty);
2753
2754 if (md->pages != md->anon && md->pages != md->dirty)
2755 seq_printf(m, " mapped=%lu", md->pages);
2756
2757 if (md->mapcount_max > 1)
2758 seq_printf(m, " mapmax=%lu", md->mapcount_max);
2759
2760 if (md->swapcache)
2761 seq_printf(m, " swapcache=%lu", md->swapcache);
2762
2763 if (md->active < md->pages && !is_vm_hugetlb_page(vma))
2764 seq_printf(m, " active=%lu", md->active);
2765
2766 if (md->writeback)
2767 seq_printf(m, " writeback=%lu", md->writeback);
2768
2769 for_each_node_state(nid, N_MEMORY)
2770 if (md->node[nid])
2771 seq_printf(m, " N%d=%lu", nid, md->node[nid]);
2772
2773 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10);
2774out:
2775 seq_putc(m, '\n');
2776 return 0;
2777}
2778
2779static const struct seq_operations proc_pid_numa_maps_op = {
2780 .start = m_start,
2781 .next = m_next,
2782 .stop = m_stop,
2783 .show = show_numa_map,
2784};
2785
2786static int pid_numa_maps_open(struct inode *inode, struct file *file)
2787{
2788 return proc_maps_open(inode, file, &proc_pid_numa_maps_op,
2789 sizeof(struct numa_maps_private));
2790}
2791
2792const struct file_operations proc_pid_numa_maps_operations = {
2793 .open = pid_numa_maps_open,
2794 .read = seq_read,
2795 .llseek = seq_lseek,
2796 .release = proc_map_release,
2797};
2798
2799#endif /* CONFIG_NUMA */