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Merge tag 'iommu-updates-v4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/joro...
[deliverable/linux.git] / fs / proc / task_mmu.c
1 #include <linux/mm.h>
2 #include <linux/vmacache.h>
3 #include <linux/hugetlb.h>
4 #include <linux/huge_mm.h>
5 #include <linux/mount.h>
6 #include <linux/seq_file.h>
7 #include <linux/highmem.h>
8 #include <linux/ptrace.h>
9 #include <linux/slab.h>
10 #include <linux/pagemap.h>
11 #include <linux/mempolicy.h>
12 #include <linux/rmap.h>
13 #include <linux/swap.h>
14 #include <linux/swapops.h>
15 #include <linux/mmu_notifier.h>
16
17 #include <asm/elf.h>
18 #include <asm/uaccess.h>
19 #include <asm/tlbflush.h>
20 #include "internal.h"
21
22 void task_mem(struct seq_file *m, struct mm_struct *mm)
23 {
24 unsigned long data, text, lib, swap, ptes, pmds;
25 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
26
27 /*
28 * Note: to minimize their overhead, mm maintains hiwater_vm and
29 * hiwater_rss only when about to *lower* total_vm or rss. Any
30 * collector of these hiwater stats must therefore get total_vm
31 * and rss too, which will usually be the higher. Barriers? not
32 * worth the effort, such snapshots can always be inconsistent.
33 */
34 hiwater_vm = total_vm = mm->total_vm;
35 if (hiwater_vm < mm->hiwater_vm)
36 hiwater_vm = mm->hiwater_vm;
37 hiwater_rss = total_rss = get_mm_rss(mm);
38 if (hiwater_rss < mm->hiwater_rss)
39 hiwater_rss = mm->hiwater_rss;
40
41 data = mm->total_vm - mm->shared_vm - mm->stack_vm;
42 text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10;
43 lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text;
44 swap = get_mm_counter(mm, MM_SWAPENTS);
45 ptes = PTRS_PER_PTE * sizeof(pte_t) * atomic_long_read(&mm->nr_ptes);
46 pmds = PTRS_PER_PMD * sizeof(pmd_t) * mm_nr_pmds(mm);
47 seq_printf(m,
48 "VmPeak:\t%8lu kB\n"
49 "VmSize:\t%8lu kB\n"
50 "VmLck:\t%8lu kB\n"
51 "VmPin:\t%8lu kB\n"
52 "VmHWM:\t%8lu kB\n"
53 "VmRSS:\t%8lu kB\n"
54 "VmData:\t%8lu kB\n"
55 "VmStk:\t%8lu kB\n"
56 "VmExe:\t%8lu kB\n"
57 "VmLib:\t%8lu kB\n"
58 "VmPTE:\t%8lu kB\n"
59 "VmPMD:\t%8lu kB\n"
60 "VmSwap:\t%8lu kB\n",
61 hiwater_vm << (PAGE_SHIFT-10),
62 total_vm << (PAGE_SHIFT-10),
63 mm->locked_vm << (PAGE_SHIFT-10),
64 mm->pinned_vm << (PAGE_SHIFT-10),
65 hiwater_rss << (PAGE_SHIFT-10),
66 total_rss << (PAGE_SHIFT-10),
67 data << (PAGE_SHIFT-10),
68 mm->stack_vm << (PAGE_SHIFT-10), text, lib,
69 ptes >> 10,
70 pmds >> 10,
71 swap << (PAGE_SHIFT-10));
72 }
73
74 unsigned long task_vsize(struct mm_struct *mm)
75 {
76 return PAGE_SIZE * mm->total_vm;
77 }
78
79 unsigned long task_statm(struct mm_struct *mm,
80 unsigned long *shared, unsigned long *text,
81 unsigned long *data, unsigned long *resident)
82 {
83 *shared = get_mm_counter(mm, MM_FILEPAGES);
84 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
85 >> PAGE_SHIFT;
86 *data = mm->total_vm - mm->shared_vm;
87 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
88 return mm->total_vm;
89 }
90
91 #ifdef CONFIG_NUMA
92 /*
93 * Save get_task_policy() for show_numa_map().
94 */
95 static void hold_task_mempolicy(struct proc_maps_private *priv)
96 {
97 struct task_struct *task = priv->task;
98
99 task_lock(task);
100 priv->task_mempolicy = get_task_policy(task);
101 mpol_get(priv->task_mempolicy);
102 task_unlock(task);
103 }
104 static void release_task_mempolicy(struct proc_maps_private *priv)
105 {
106 mpol_put(priv->task_mempolicy);
107 }
108 #else
109 static void hold_task_mempolicy(struct proc_maps_private *priv)
110 {
111 }
112 static void release_task_mempolicy(struct proc_maps_private *priv)
113 {
114 }
115 #endif
116
117 static void vma_stop(struct proc_maps_private *priv)
118 {
119 struct mm_struct *mm = priv->mm;
120
121 release_task_mempolicy(priv);
122 up_read(&mm->mmap_sem);
123 mmput(mm);
124 }
125
126 static struct vm_area_struct *
127 m_next_vma(struct proc_maps_private *priv, struct vm_area_struct *vma)
128 {
129 if (vma == priv->tail_vma)
130 return NULL;
131 return vma->vm_next ?: priv->tail_vma;
132 }
133
134 static void m_cache_vma(struct seq_file *m, struct vm_area_struct *vma)
135 {
136 if (m->count < m->size) /* vma is copied successfully */
137 m->version = m_next_vma(m->private, vma) ? vma->vm_start : -1UL;
138 }
139
140 static void *m_start(struct seq_file *m, loff_t *ppos)
141 {
142 struct proc_maps_private *priv = m->private;
143 unsigned long last_addr = m->version;
144 struct mm_struct *mm;
145 struct vm_area_struct *vma;
146 unsigned int pos = *ppos;
147
148 /* See m_cache_vma(). Zero at the start or after lseek. */
149 if (last_addr == -1UL)
150 return NULL;
151
152 priv->task = get_proc_task(priv->inode);
153 if (!priv->task)
154 return ERR_PTR(-ESRCH);
155
156 mm = priv->mm;
157 if (!mm || !atomic_inc_not_zero(&mm->mm_users))
158 return NULL;
159
160 down_read(&mm->mmap_sem);
161 hold_task_mempolicy(priv);
162 priv->tail_vma = get_gate_vma(mm);
163
164 if (last_addr) {
165 vma = find_vma(mm, last_addr);
166 if (vma && (vma = m_next_vma(priv, vma)))
167 return vma;
168 }
169
170 m->version = 0;
171 if (pos < mm->map_count) {
172 for (vma = mm->mmap; pos; pos--) {
173 m->version = vma->vm_start;
174 vma = vma->vm_next;
175 }
176 return vma;
177 }
178
179 /* we do not bother to update m->version in this case */
180 if (pos == mm->map_count && priv->tail_vma)
181 return priv->tail_vma;
182
183 vma_stop(priv);
184 return NULL;
185 }
186
187 static void *m_next(struct seq_file *m, void *v, loff_t *pos)
188 {
189 struct proc_maps_private *priv = m->private;
190 struct vm_area_struct *next;
191
192 (*pos)++;
193 next = m_next_vma(priv, v);
194 if (!next)
195 vma_stop(priv);
196 return next;
197 }
198
199 static void m_stop(struct seq_file *m, void *v)
200 {
201 struct proc_maps_private *priv = m->private;
202
203 if (!IS_ERR_OR_NULL(v))
204 vma_stop(priv);
205 if (priv->task) {
206 put_task_struct(priv->task);
207 priv->task = NULL;
208 }
209 }
210
211 static int proc_maps_open(struct inode *inode, struct file *file,
212 const struct seq_operations *ops, int psize)
213 {
214 struct proc_maps_private *priv = __seq_open_private(file, ops, psize);
215
216 if (!priv)
217 return -ENOMEM;
218
219 priv->inode = inode;
220 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
221 if (IS_ERR(priv->mm)) {
222 int err = PTR_ERR(priv->mm);
223
224 seq_release_private(inode, file);
225 return err;
226 }
227
228 return 0;
229 }
230
231 static int proc_map_release(struct inode *inode, struct file *file)
232 {
233 struct seq_file *seq = file->private_data;
234 struct proc_maps_private *priv = seq->private;
235
236 if (priv->mm)
237 mmdrop(priv->mm);
238
239 return seq_release_private(inode, file);
240 }
241
242 static int do_maps_open(struct inode *inode, struct file *file,
243 const struct seq_operations *ops)
244 {
245 return proc_maps_open(inode, file, ops,
246 sizeof(struct proc_maps_private));
247 }
248
249 static pid_t pid_of_stack(struct proc_maps_private *priv,
250 struct vm_area_struct *vma, bool is_pid)
251 {
252 struct inode *inode = priv->inode;
253 struct task_struct *task;
254 pid_t ret = 0;
255
256 rcu_read_lock();
257 task = pid_task(proc_pid(inode), PIDTYPE_PID);
258 if (task) {
259 task = task_of_stack(task, vma, is_pid);
260 if (task)
261 ret = task_pid_nr_ns(task, inode->i_sb->s_fs_info);
262 }
263 rcu_read_unlock();
264
265 return ret;
266 }
267
268 static void
269 show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid)
270 {
271 struct mm_struct *mm = vma->vm_mm;
272 struct file *file = vma->vm_file;
273 struct proc_maps_private *priv = m->private;
274 vm_flags_t flags = vma->vm_flags;
275 unsigned long ino = 0;
276 unsigned long long pgoff = 0;
277 unsigned long start, end;
278 dev_t dev = 0;
279 const char *name = NULL;
280
281 if (file) {
282 struct inode *inode = file_inode(vma->vm_file);
283 dev = inode->i_sb->s_dev;
284 ino = inode->i_ino;
285 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
286 }
287
288 /* We don't show the stack guard page in /proc/maps */
289 start = vma->vm_start;
290 if (stack_guard_page_start(vma, start))
291 start += PAGE_SIZE;
292 end = vma->vm_end;
293 if (stack_guard_page_end(vma, end))
294 end -= PAGE_SIZE;
295
296 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
297 seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu ",
298 start,
299 end,
300 flags & VM_READ ? 'r' : '-',
301 flags & VM_WRITE ? 'w' : '-',
302 flags & VM_EXEC ? 'x' : '-',
303 flags & VM_MAYSHARE ? 's' : 'p',
304 pgoff,
305 MAJOR(dev), MINOR(dev), ino);
306
307 /*
308 * Print the dentry name for named mappings, and a
309 * special [heap] marker for the heap:
310 */
311 if (file) {
312 seq_pad(m, ' ');
313 seq_file_path(m, file, "\n");
314 goto done;
315 }
316
317 if (vma->vm_ops && vma->vm_ops->name) {
318 name = vma->vm_ops->name(vma);
319 if (name)
320 goto done;
321 }
322
323 name = arch_vma_name(vma);
324 if (!name) {
325 pid_t tid;
326
327 if (!mm) {
328 name = "[vdso]";
329 goto done;
330 }
331
332 if (vma->vm_start <= mm->brk &&
333 vma->vm_end >= mm->start_brk) {
334 name = "[heap]";
335 goto done;
336 }
337
338 tid = pid_of_stack(priv, vma, is_pid);
339 if (tid != 0) {
340 /*
341 * Thread stack in /proc/PID/task/TID/maps or
342 * the main process stack.
343 */
344 if (!is_pid || (vma->vm_start <= mm->start_stack &&
345 vma->vm_end >= mm->start_stack)) {
346 name = "[stack]";
347 } else {
348 /* Thread stack in /proc/PID/maps */
349 seq_pad(m, ' ');
350 seq_printf(m, "[stack:%d]", tid);
351 }
352 }
353 }
354
355 done:
356 if (name) {
357 seq_pad(m, ' ');
358 seq_puts(m, name);
359 }
360 seq_putc(m, '\n');
361 }
362
363 static int show_map(struct seq_file *m, void *v, int is_pid)
364 {
365 show_map_vma(m, v, is_pid);
366 m_cache_vma(m, v);
367 return 0;
368 }
369
370 static int show_pid_map(struct seq_file *m, void *v)
371 {
372 return show_map(m, v, 1);
373 }
374
375 static int show_tid_map(struct seq_file *m, void *v)
376 {
377 return show_map(m, v, 0);
378 }
379
380 static const struct seq_operations proc_pid_maps_op = {
381 .start = m_start,
382 .next = m_next,
383 .stop = m_stop,
384 .show = show_pid_map
385 };
386
387 static const struct seq_operations proc_tid_maps_op = {
388 .start = m_start,
389 .next = m_next,
390 .stop = m_stop,
391 .show = show_tid_map
392 };
393
394 static int pid_maps_open(struct inode *inode, struct file *file)
395 {
396 return do_maps_open(inode, file, &proc_pid_maps_op);
397 }
398
399 static int tid_maps_open(struct inode *inode, struct file *file)
400 {
401 return do_maps_open(inode, file, &proc_tid_maps_op);
402 }
403
404 const struct file_operations proc_pid_maps_operations = {
405 .open = pid_maps_open,
406 .read = seq_read,
407 .llseek = seq_lseek,
408 .release = proc_map_release,
409 };
410
411 const struct file_operations proc_tid_maps_operations = {
412 .open = tid_maps_open,
413 .read = seq_read,
414 .llseek = seq_lseek,
415 .release = proc_map_release,
416 };
417
418 /*
419 * Proportional Set Size(PSS): my share of RSS.
420 *
421 * PSS of a process is the count of pages it has in memory, where each
422 * page is divided by the number of processes sharing it. So if a
423 * process has 1000 pages all to itself, and 1000 shared with one other
424 * process, its PSS will be 1500.
425 *
426 * To keep (accumulated) division errors low, we adopt a 64bit
427 * fixed-point pss counter to minimize division errors. So (pss >>
428 * PSS_SHIFT) would be the real byte count.
429 *
430 * A shift of 12 before division means (assuming 4K page size):
431 * - 1M 3-user-pages add up to 8KB errors;
432 * - supports mapcount up to 2^24, or 16M;
433 * - supports PSS up to 2^52 bytes, or 4PB.
434 */
435 #define PSS_SHIFT 12
436
437 #ifdef CONFIG_PROC_PAGE_MONITOR
438 struct mem_size_stats {
439 unsigned long resident;
440 unsigned long shared_clean;
441 unsigned long shared_dirty;
442 unsigned long private_clean;
443 unsigned long private_dirty;
444 unsigned long referenced;
445 unsigned long anonymous;
446 unsigned long anonymous_thp;
447 unsigned long swap;
448 u64 pss;
449 };
450
451 static void smaps_account(struct mem_size_stats *mss, struct page *page,
452 unsigned long size, bool young, bool dirty)
453 {
454 int mapcount;
455
456 if (PageAnon(page))
457 mss->anonymous += size;
458
459 mss->resident += size;
460 /* Accumulate the size in pages that have been accessed. */
461 if (young || PageReferenced(page))
462 mss->referenced += size;
463 mapcount = page_mapcount(page);
464 if (mapcount >= 2) {
465 u64 pss_delta;
466
467 if (dirty || PageDirty(page))
468 mss->shared_dirty += size;
469 else
470 mss->shared_clean += size;
471 pss_delta = (u64)size << PSS_SHIFT;
472 do_div(pss_delta, mapcount);
473 mss->pss += pss_delta;
474 } else {
475 if (dirty || PageDirty(page))
476 mss->private_dirty += size;
477 else
478 mss->private_clean += size;
479 mss->pss += (u64)size << PSS_SHIFT;
480 }
481 }
482
483 static void smaps_pte_entry(pte_t *pte, unsigned long addr,
484 struct mm_walk *walk)
485 {
486 struct mem_size_stats *mss = walk->private;
487 struct vm_area_struct *vma = walk->vma;
488 struct page *page = NULL;
489
490 if (pte_present(*pte)) {
491 page = vm_normal_page(vma, addr, *pte);
492 } else if (is_swap_pte(*pte)) {
493 swp_entry_t swpent = pte_to_swp_entry(*pte);
494
495 if (!non_swap_entry(swpent))
496 mss->swap += PAGE_SIZE;
497 else if (is_migration_entry(swpent))
498 page = migration_entry_to_page(swpent);
499 }
500
501 if (!page)
502 return;
503 smaps_account(mss, page, PAGE_SIZE, pte_young(*pte), pte_dirty(*pte));
504 }
505
506 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
507 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
508 struct mm_walk *walk)
509 {
510 struct mem_size_stats *mss = walk->private;
511 struct vm_area_struct *vma = walk->vma;
512 struct page *page;
513
514 /* FOLL_DUMP will return -EFAULT on huge zero page */
515 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
516 if (IS_ERR_OR_NULL(page))
517 return;
518 mss->anonymous_thp += HPAGE_PMD_SIZE;
519 smaps_account(mss, page, HPAGE_PMD_SIZE,
520 pmd_young(*pmd), pmd_dirty(*pmd));
521 }
522 #else
523 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
524 struct mm_walk *walk)
525 {
526 }
527 #endif
528
529 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
530 struct mm_walk *walk)
531 {
532 struct vm_area_struct *vma = walk->vma;
533 pte_t *pte;
534 spinlock_t *ptl;
535
536 if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
537 smaps_pmd_entry(pmd, addr, walk);
538 spin_unlock(ptl);
539 return 0;
540 }
541
542 if (pmd_trans_unstable(pmd))
543 return 0;
544 /*
545 * The mmap_sem held all the way back in m_start() is what
546 * keeps khugepaged out of here and from collapsing things
547 * in here.
548 */
549 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
550 for (; addr != end; pte++, addr += PAGE_SIZE)
551 smaps_pte_entry(pte, addr, walk);
552 pte_unmap_unlock(pte - 1, ptl);
553 cond_resched();
554 return 0;
555 }
556
557 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
558 {
559 /*
560 * Don't forget to update Documentation/ on changes.
561 */
562 static const char mnemonics[BITS_PER_LONG][2] = {
563 /*
564 * In case if we meet a flag we don't know about.
565 */
566 [0 ... (BITS_PER_LONG-1)] = "??",
567
568 [ilog2(VM_READ)] = "rd",
569 [ilog2(VM_WRITE)] = "wr",
570 [ilog2(VM_EXEC)] = "ex",
571 [ilog2(VM_SHARED)] = "sh",
572 [ilog2(VM_MAYREAD)] = "mr",
573 [ilog2(VM_MAYWRITE)] = "mw",
574 [ilog2(VM_MAYEXEC)] = "me",
575 [ilog2(VM_MAYSHARE)] = "ms",
576 [ilog2(VM_GROWSDOWN)] = "gd",
577 [ilog2(VM_PFNMAP)] = "pf",
578 [ilog2(VM_DENYWRITE)] = "dw",
579 #ifdef CONFIG_X86_INTEL_MPX
580 [ilog2(VM_MPX)] = "mp",
581 #endif
582 [ilog2(VM_LOCKED)] = "lo",
583 [ilog2(VM_IO)] = "io",
584 [ilog2(VM_SEQ_READ)] = "sr",
585 [ilog2(VM_RAND_READ)] = "rr",
586 [ilog2(VM_DONTCOPY)] = "dc",
587 [ilog2(VM_DONTEXPAND)] = "de",
588 [ilog2(VM_ACCOUNT)] = "ac",
589 [ilog2(VM_NORESERVE)] = "nr",
590 [ilog2(VM_HUGETLB)] = "ht",
591 [ilog2(VM_ARCH_1)] = "ar",
592 [ilog2(VM_DONTDUMP)] = "dd",
593 #ifdef CONFIG_MEM_SOFT_DIRTY
594 [ilog2(VM_SOFTDIRTY)] = "sd",
595 #endif
596 [ilog2(VM_MIXEDMAP)] = "mm",
597 [ilog2(VM_HUGEPAGE)] = "hg",
598 [ilog2(VM_NOHUGEPAGE)] = "nh",
599 [ilog2(VM_MERGEABLE)] = "mg",
600 [ilog2(VM_UFFD_MISSING)]= "um",
601 [ilog2(VM_UFFD_WP)] = "uw",
602 };
603 size_t i;
604
605 seq_puts(m, "VmFlags: ");
606 for (i = 0; i < BITS_PER_LONG; i++) {
607 if (vma->vm_flags & (1UL << i)) {
608 seq_printf(m, "%c%c ",
609 mnemonics[i][0], mnemonics[i][1]);
610 }
611 }
612 seq_putc(m, '\n');
613 }
614
615 static int show_smap(struct seq_file *m, void *v, int is_pid)
616 {
617 struct vm_area_struct *vma = v;
618 struct mem_size_stats mss;
619 struct mm_walk smaps_walk = {
620 .pmd_entry = smaps_pte_range,
621 .mm = vma->vm_mm,
622 .private = &mss,
623 };
624
625 memset(&mss, 0, sizeof mss);
626 /* mmap_sem is held in m_start */
627 walk_page_vma(vma, &smaps_walk);
628
629 show_map_vma(m, vma, is_pid);
630
631 seq_printf(m,
632 "Size: %8lu kB\n"
633 "Rss: %8lu kB\n"
634 "Pss: %8lu kB\n"
635 "Shared_Clean: %8lu kB\n"
636 "Shared_Dirty: %8lu kB\n"
637 "Private_Clean: %8lu kB\n"
638 "Private_Dirty: %8lu kB\n"
639 "Referenced: %8lu kB\n"
640 "Anonymous: %8lu kB\n"
641 "AnonHugePages: %8lu kB\n"
642 "Swap: %8lu kB\n"
643 "KernelPageSize: %8lu kB\n"
644 "MMUPageSize: %8lu kB\n"
645 "Locked: %8lu kB\n",
646 (vma->vm_end - vma->vm_start) >> 10,
647 mss.resident >> 10,
648 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)),
649 mss.shared_clean >> 10,
650 mss.shared_dirty >> 10,
651 mss.private_clean >> 10,
652 mss.private_dirty >> 10,
653 mss.referenced >> 10,
654 mss.anonymous >> 10,
655 mss.anonymous_thp >> 10,
656 mss.swap >> 10,
657 vma_kernel_pagesize(vma) >> 10,
658 vma_mmu_pagesize(vma) >> 10,
659 (vma->vm_flags & VM_LOCKED) ?
660 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0);
661
662 show_smap_vma_flags(m, vma);
663 m_cache_vma(m, vma);
664 return 0;
665 }
666
667 static int show_pid_smap(struct seq_file *m, void *v)
668 {
669 return show_smap(m, v, 1);
670 }
671
672 static int show_tid_smap(struct seq_file *m, void *v)
673 {
674 return show_smap(m, v, 0);
675 }
676
677 static const struct seq_operations proc_pid_smaps_op = {
678 .start = m_start,
679 .next = m_next,
680 .stop = m_stop,
681 .show = show_pid_smap
682 };
683
684 static const struct seq_operations proc_tid_smaps_op = {
685 .start = m_start,
686 .next = m_next,
687 .stop = m_stop,
688 .show = show_tid_smap
689 };
690
691 static int pid_smaps_open(struct inode *inode, struct file *file)
692 {
693 return do_maps_open(inode, file, &proc_pid_smaps_op);
694 }
695
696 static int tid_smaps_open(struct inode *inode, struct file *file)
697 {
698 return do_maps_open(inode, file, &proc_tid_smaps_op);
699 }
700
701 const struct file_operations proc_pid_smaps_operations = {
702 .open = pid_smaps_open,
703 .read = seq_read,
704 .llseek = seq_lseek,
705 .release = proc_map_release,
706 };
707
708 const struct file_operations proc_tid_smaps_operations = {
709 .open = tid_smaps_open,
710 .read = seq_read,
711 .llseek = seq_lseek,
712 .release = proc_map_release,
713 };
714
715 /*
716 * We do not want to have constant page-shift bits sitting in
717 * pagemap entries and are about to reuse them some time soon.
718 *
719 * Here's the "migration strategy":
720 * 1. when the system boots these bits remain what they are,
721 * but a warning about future change is printed in log;
722 * 2. once anyone clears soft-dirty bits via clear_refs file,
723 * these flag is set to denote, that user is aware of the
724 * new API and those page-shift bits change their meaning.
725 * The respective warning is printed in dmesg;
726 * 3. In a couple of releases we will remove all the mentions
727 * of page-shift in pagemap entries.
728 */
729
730 static bool soft_dirty_cleared __read_mostly;
731
732 enum clear_refs_types {
733 CLEAR_REFS_ALL = 1,
734 CLEAR_REFS_ANON,
735 CLEAR_REFS_MAPPED,
736 CLEAR_REFS_SOFT_DIRTY,
737 CLEAR_REFS_MM_HIWATER_RSS,
738 CLEAR_REFS_LAST,
739 };
740
741 struct clear_refs_private {
742 enum clear_refs_types type;
743 };
744
745 #ifdef CONFIG_MEM_SOFT_DIRTY
746 static inline void clear_soft_dirty(struct vm_area_struct *vma,
747 unsigned long addr, pte_t *pte)
748 {
749 /*
750 * The soft-dirty tracker uses #PF-s to catch writes
751 * to pages, so write-protect the pte as well. See the
752 * Documentation/vm/soft-dirty.txt for full description
753 * of how soft-dirty works.
754 */
755 pte_t ptent = *pte;
756
757 if (pte_present(ptent)) {
758 ptent = pte_wrprotect(ptent);
759 ptent = pte_clear_flags(ptent, _PAGE_SOFT_DIRTY);
760 } else if (is_swap_pte(ptent)) {
761 ptent = pte_swp_clear_soft_dirty(ptent);
762 }
763
764 set_pte_at(vma->vm_mm, addr, pte, ptent);
765 }
766
767 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
768 unsigned long addr, pmd_t *pmdp)
769 {
770 pmd_t pmd = *pmdp;
771
772 pmd = pmd_wrprotect(pmd);
773 pmd = pmd_clear_flags(pmd, _PAGE_SOFT_DIRTY);
774
775 if (vma->vm_flags & VM_SOFTDIRTY)
776 vma->vm_flags &= ~VM_SOFTDIRTY;
777
778 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
779 }
780
781 #else
782
783 static inline void clear_soft_dirty(struct vm_area_struct *vma,
784 unsigned long addr, pte_t *pte)
785 {
786 }
787
788 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
789 unsigned long addr, pmd_t *pmdp)
790 {
791 }
792 #endif
793
794 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
795 unsigned long end, struct mm_walk *walk)
796 {
797 struct clear_refs_private *cp = walk->private;
798 struct vm_area_struct *vma = walk->vma;
799 pte_t *pte, ptent;
800 spinlock_t *ptl;
801 struct page *page;
802
803 if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
804 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
805 clear_soft_dirty_pmd(vma, addr, pmd);
806 goto out;
807 }
808
809 page = pmd_page(*pmd);
810
811 /* Clear accessed and referenced bits. */
812 pmdp_test_and_clear_young(vma, addr, pmd);
813 ClearPageReferenced(page);
814 out:
815 spin_unlock(ptl);
816 return 0;
817 }
818
819 if (pmd_trans_unstable(pmd))
820 return 0;
821
822 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
823 for (; addr != end; pte++, addr += PAGE_SIZE) {
824 ptent = *pte;
825
826 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
827 clear_soft_dirty(vma, addr, pte);
828 continue;
829 }
830
831 if (!pte_present(ptent))
832 continue;
833
834 page = vm_normal_page(vma, addr, ptent);
835 if (!page)
836 continue;
837
838 /* Clear accessed and referenced bits. */
839 ptep_test_and_clear_young(vma, addr, pte);
840 ClearPageReferenced(page);
841 }
842 pte_unmap_unlock(pte - 1, ptl);
843 cond_resched();
844 return 0;
845 }
846
847 static int clear_refs_test_walk(unsigned long start, unsigned long end,
848 struct mm_walk *walk)
849 {
850 struct clear_refs_private *cp = walk->private;
851 struct vm_area_struct *vma = walk->vma;
852
853 if (vma->vm_flags & VM_PFNMAP)
854 return 1;
855
856 /*
857 * Writing 1 to /proc/pid/clear_refs affects all pages.
858 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages.
859 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages.
860 * Writing 4 to /proc/pid/clear_refs affects all pages.
861 */
862 if (cp->type == CLEAR_REFS_ANON && vma->vm_file)
863 return 1;
864 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file)
865 return 1;
866 return 0;
867 }
868
869 static ssize_t clear_refs_write(struct file *file, const char __user *buf,
870 size_t count, loff_t *ppos)
871 {
872 struct task_struct *task;
873 char buffer[PROC_NUMBUF];
874 struct mm_struct *mm;
875 struct vm_area_struct *vma;
876 enum clear_refs_types type;
877 int itype;
878 int rv;
879
880 memset(buffer, 0, sizeof(buffer));
881 if (count > sizeof(buffer) - 1)
882 count = sizeof(buffer) - 1;
883 if (copy_from_user(buffer, buf, count))
884 return -EFAULT;
885 rv = kstrtoint(strstrip(buffer), 10, &itype);
886 if (rv < 0)
887 return rv;
888 type = (enum clear_refs_types)itype;
889 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
890 return -EINVAL;
891
892 if (type == CLEAR_REFS_SOFT_DIRTY) {
893 soft_dirty_cleared = true;
894 pr_warn_once("The pagemap bits 55-60 has changed their meaning!"
895 " See the linux/Documentation/vm/pagemap.txt for "
896 "details.\n");
897 }
898
899 task = get_proc_task(file_inode(file));
900 if (!task)
901 return -ESRCH;
902 mm = get_task_mm(task);
903 if (mm) {
904 struct clear_refs_private cp = {
905 .type = type,
906 };
907 struct mm_walk clear_refs_walk = {
908 .pmd_entry = clear_refs_pte_range,
909 .test_walk = clear_refs_test_walk,
910 .mm = mm,
911 .private = &cp,
912 };
913
914 if (type == CLEAR_REFS_MM_HIWATER_RSS) {
915 /*
916 * Writing 5 to /proc/pid/clear_refs resets the peak
917 * resident set size to this mm's current rss value.
918 */
919 down_write(&mm->mmap_sem);
920 reset_mm_hiwater_rss(mm);
921 up_write(&mm->mmap_sem);
922 goto out_mm;
923 }
924
925 down_read(&mm->mmap_sem);
926 if (type == CLEAR_REFS_SOFT_DIRTY) {
927 for (vma = mm->mmap; vma; vma = vma->vm_next) {
928 if (!(vma->vm_flags & VM_SOFTDIRTY))
929 continue;
930 up_read(&mm->mmap_sem);
931 down_write(&mm->mmap_sem);
932 for (vma = mm->mmap; vma; vma = vma->vm_next) {
933 vma->vm_flags &= ~VM_SOFTDIRTY;
934 vma_set_page_prot(vma);
935 }
936 downgrade_write(&mm->mmap_sem);
937 break;
938 }
939 mmu_notifier_invalidate_range_start(mm, 0, -1);
940 }
941 walk_page_range(0, ~0UL, &clear_refs_walk);
942 if (type == CLEAR_REFS_SOFT_DIRTY)
943 mmu_notifier_invalidate_range_end(mm, 0, -1);
944 flush_tlb_mm(mm);
945 up_read(&mm->mmap_sem);
946 out_mm:
947 mmput(mm);
948 }
949 put_task_struct(task);
950
951 return count;
952 }
953
954 const struct file_operations proc_clear_refs_operations = {
955 .write = clear_refs_write,
956 .llseek = noop_llseek,
957 };
958
959 typedef struct {
960 u64 pme;
961 } pagemap_entry_t;
962
963 struct pagemapread {
964 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */
965 pagemap_entry_t *buffer;
966 bool v2;
967 };
968
969 #define PAGEMAP_WALK_SIZE (PMD_SIZE)
970 #define PAGEMAP_WALK_MASK (PMD_MASK)
971
972 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t)
973 #define PM_STATUS_BITS 3
974 #define PM_STATUS_OFFSET (64 - PM_STATUS_BITS)
975 #define PM_STATUS_MASK (((1LL << PM_STATUS_BITS) - 1) << PM_STATUS_OFFSET)
976 #define PM_STATUS(nr) (((nr) << PM_STATUS_OFFSET) & PM_STATUS_MASK)
977 #define PM_PSHIFT_BITS 6
978 #define PM_PSHIFT_OFFSET (PM_STATUS_OFFSET - PM_PSHIFT_BITS)
979 #define PM_PSHIFT_MASK (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET)
980 #define __PM_PSHIFT(x) (((u64) (x) << PM_PSHIFT_OFFSET) & PM_PSHIFT_MASK)
981 #define PM_PFRAME_MASK ((1LL << PM_PSHIFT_OFFSET) - 1)
982 #define PM_PFRAME(x) ((x) & PM_PFRAME_MASK)
983 /* in "new" pagemap pshift bits are occupied with more status bits */
984 #define PM_STATUS2(v2, x) (__PM_PSHIFT(v2 ? x : PAGE_SHIFT))
985
986 #define __PM_SOFT_DIRTY (1LL)
987 #define PM_PRESENT PM_STATUS(4LL)
988 #define PM_SWAP PM_STATUS(2LL)
989 #define PM_FILE PM_STATUS(1LL)
990 #define PM_NOT_PRESENT(v2) PM_STATUS2(v2, 0)
991 #define PM_END_OF_BUFFER 1
992
993 static inline pagemap_entry_t make_pme(u64 val)
994 {
995 return (pagemap_entry_t) { .pme = val };
996 }
997
998 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme,
999 struct pagemapread *pm)
1000 {
1001 pm->buffer[pm->pos++] = *pme;
1002 if (pm->pos >= pm->len)
1003 return PM_END_OF_BUFFER;
1004 return 0;
1005 }
1006
1007 static int pagemap_pte_hole(unsigned long start, unsigned long end,
1008 struct mm_walk *walk)
1009 {
1010 struct pagemapread *pm = walk->private;
1011 unsigned long addr = start;
1012 int err = 0;
1013
1014 while (addr < end) {
1015 struct vm_area_struct *vma = find_vma(walk->mm, addr);
1016 pagemap_entry_t pme = make_pme(PM_NOT_PRESENT(pm->v2));
1017 /* End of address space hole, which we mark as non-present. */
1018 unsigned long hole_end;
1019
1020 if (vma)
1021 hole_end = min(end, vma->vm_start);
1022 else
1023 hole_end = end;
1024
1025 for (; addr < hole_end; addr += PAGE_SIZE) {
1026 err = add_to_pagemap(addr, &pme, pm);
1027 if (err)
1028 goto out;
1029 }
1030
1031 if (!vma)
1032 break;
1033
1034 /* Addresses in the VMA. */
1035 if (vma->vm_flags & VM_SOFTDIRTY)
1036 pme.pme |= PM_STATUS2(pm->v2, __PM_SOFT_DIRTY);
1037 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) {
1038 err = add_to_pagemap(addr, &pme, pm);
1039 if (err)
1040 goto out;
1041 }
1042 }
1043 out:
1044 return err;
1045 }
1046
1047 static void pte_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm,
1048 struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1049 {
1050 u64 frame, flags;
1051 struct page *page = NULL;
1052 int flags2 = 0;
1053
1054 if (pte_present(pte)) {
1055 frame = pte_pfn(pte);
1056 flags = PM_PRESENT;
1057 page = vm_normal_page(vma, addr, pte);
1058 if (pte_soft_dirty(pte))
1059 flags2 |= __PM_SOFT_DIRTY;
1060 } else if (is_swap_pte(pte)) {
1061 swp_entry_t entry;
1062 if (pte_swp_soft_dirty(pte))
1063 flags2 |= __PM_SOFT_DIRTY;
1064 entry = pte_to_swp_entry(pte);
1065 frame = swp_type(entry) |
1066 (swp_offset(entry) << MAX_SWAPFILES_SHIFT);
1067 flags = PM_SWAP;
1068 if (is_migration_entry(entry))
1069 page = migration_entry_to_page(entry);
1070 } else {
1071 if (vma->vm_flags & VM_SOFTDIRTY)
1072 flags2 |= __PM_SOFT_DIRTY;
1073 *pme = make_pme(PM_NOT_PRESENT(pm->v2) | PM_STATUS2(pm->v2, flags2));
1074 return;
1075 }
1076
1077 if (page && !PageAnon(page))
1078 flags |= PM_FILE;
1079 if ((vma->vm_flags & VM_SOFTDIRTY))
1080 flags2 |= __PM_SOFT_DIRTY;
1081
1082 *pme = make_pme(PM_PFRAME(frame) | PM_STATUS2(pm->v2, flags2) | flags);
1083 }
1084
1085 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1086 static void thp_pmd_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm,
1087 pmd_t pmd, int offset, int pmd_flags2)
1088 {
1089 /*
1090 * Currently pmd for thp is always present because thp can not be
1091 * swapped-out, migrated, or HWPOISONed (split in such cases instead.)
1092 * This if-check is just to prepare for future implementation.
1093 */
1094 if (pmd_present(pmd))
1095 *pme = make_pme(PM_PFRAME(pmd_pfn(pmd) + offset)
1096 | PM_STATUS2(pm->v2, pmd_flags2) | PM_PRESENT);
1097 else
1098 *pme = make_pme(PM_NOT_PRESENT(pm->v2) | PM_STATUS2(pm->v2, pmd_flags2));
1099 }
1100 #else
1101 static inline void thp_pmd_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm,
1102 pmd_t pmd, int offset, int pmd_flags2)
1103 {
1104 }
1105 #endif
1106
1107 static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
1108 struct mm_walk *walk)
1109 {
1110 struct vm_area_struct *vma = walk->vma;
1111 struct pagemapread *pm = walk->private;
1112 spinlock_t *ptl;
1113 pte_t *pte, *orig_pte;
1114 int err = 0;
1115
1116 if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
1117 int pmd_flags2;
1118
1119 if ((vma->vm_flags & VM_SOFTDIRTY) || pmd_soft_dirty(*pmd))
1120 pmd_flags2 = __PM_SOFT_DIRTY;
1121 else
1122 pmd_flags2 = 0;
1123
1124 for (; addr != end; addr += PAGE_SIZE) {
1125 unsigned long offset;
1126 pagemap_entry_t pme;
1127
1128 offset = (addr & ~PAGEMAP_WALK_MASK) >>
1129 PAGE_SHIFT;
1130 thp_pmd_to_pagemap_entry(&pme, pm, *pmd, offset, pmd_flags2);
1131 err = add_to_pagemap(addr, &pme, pm);
1132 if (err)
1133 break;
1134 }
1135 spin_unlock(ptl);
1136 return err;
1137 }
1138
1139 if (pmd_trans_unstable(pmd))
1140 return 0;
1141
1142 /*
1143 * We can assume that @vma always points to a valid one and @end never
1144 * goes beyond vma->vm_end.
1145 */
1146 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
1147 for (; addr < end; pte++, addr += PAGE_SIZE) {
1148 pagemap_entry_t pme;
1149
1150 pte_to_pagemap_entry(&pme, pm, vma, addr, *pte);
1151 err = add_to_pagemap(addr, &pme, pm);
1152 if (err)
1153 break;
1154 }
1155 pte_unmap_unlock(orig_pte, ptl);
1156
1157 cond_resched();
1158
1159 return err;
1160 }
1161
1162 #ifdef CONFIG_HUGETLB_PAGE
1163 static void huge_pte_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm,
1164 pte_t pte, int offset, int flags2)
1165 {
1166 if (pte_present(pte))
1167 *pme = make_pme(PM_PFRAME(pte_pfn(pte) + offset) |
1168 PM_STATUS2(pm->v2, flags2) |
1169 PM_PRESENT);
1170 else
1171 *pme = make_pme(PM_NOT_PRESENT(pm->v2) |
1172 PM_STATUS2(pm->v2, flags2));
1173 }
1174
1175 /* This function walks within one hugetlb entry in the single call */
1176 static int pagemap_hugetlb_range(pte_t *pte, unsigned long hmask,
1177 unsigned long addr, unsigned long end,
1178 struct mm_walk *walk)
1179 {
1180 struct pagemapread *pm = walk->private;
1181 struct vm_area_struct *vma = walk->vma;
1182 int err = 0;
1183 int flags2;
1184 pagemap_entry_t pme;
1185
1186 if (vma->vm_flags & VM_SOFTDIRTY)
1187 flags2 = __PM_SOFT_DIRTY;
1188 else
1189 flags2 = 0;
1190
1191 for (; addr != end; addr += PAGE_SIZE) {
1192 int offset = (addr & ~hmask) >> PAGE_SHIFT;
1193 huge_pte_to_pagemap_entry(&pme, pm, *pte, offset, flags2);
1194 err = add_to_pagemap(addr, &pme, pm);
1195 if (err)
1196 return err;
1197 }
1198
1199 cond_resched();
1200
1201 return err;
1202 }
1203 #endif /* HUGETLB_PAGE */
1204
1205 /*
1206 * /proc/pid/pagemap - an array mapping virtual pages to pfns
1207 *
1208 * For each page in the address space, this file contains one 64-bit entry
1209 * consisting of the following:
1210 *
1211 * Bits 0-54 page frame number (PFN) if present
1212 * Bits 0-4 swap type if swapped
1213 * Bits 5-54 swap offset if swapped
1214 * Bits 55-60 page shift (page size = 1<<page shift)
1215 * Bit 61 page is file-page or shared-anon
1216 * Bit 62 page swapped
1217 * Bit 63 page present
1218 *
1219 * If the page is not present but in swap, then the PFN contains an
1220 * encoding of the swap file number and the page's offset into the
1221 * swap. Unmapped pages return a null PFN. This allows determining
1222 * precisely which pages are mapped (or in swap) and comparing mapped
1223 * pages between processes.
1224 *
1225 * Efficient users of this interface will use /proc/pid/maps to
1226 * determine which areas of memory are actually mapped and llseek to
1227 * skip over unmapped regions.
1228 */
1229 static ssize_t pagemap_read(struct file *file, char __user *buf,
1230 size_t count, loff_t *ppos)
1231 {
1232 struct task_struct *task = get_proc_task(file_inode(file));
1233 struct mm_struct *mm;
1234 struct pagemapread pm;
1235 int ret = -ESRCH;
1236 struct mm_walk pagemap_walk = {};
1237 unsigned long src;
1238 unsigned long svpfn;
1239 unsigned long start_vaddr;
1240 unsigned long end_vaddr;
1241 int copied = 0;
1242
1243 if (!task)
1244 goto out;
1245
1246 ret = -EINVAL;
1247 /* file position must be aligned */
1248 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
1249 goto out_task;
1250
1251 ret = 0;
1252 if (!count)
1253 goto out_task;
1254
1255 pm.v2 = soft_dirty_cleared;
1256 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
1257 pm.buffer = kmalloc(pm.len * PM_ENTRY_BYTES, GFP_TEMPORARY);
1258 ret = -ENOMEM;
1259 if (!pm.buffer)
1260 goto out_task;
1261
1262 mm = mm_access(task, PTRACE_MODE_READ);
1263 ret = PTR_ERR(mm);
1264 if (!mm || IS_ERR(mm))
1265 goto out_free;
1266
1267 pagemap_walk.pmd_entry = pagemap_pte_range;
1268 pagemap_walk.pte_hole = pagemap_pte_hole;
1269 #ifdef CONFIG_HUGETLB_PAGE
1270 pagemap_walk.hugetlb_entry = pagemap_hugetlb_range;
1271 #endif
1272 pagemap_walk.mm = mm;
1273 pagemap_walk.private = &pm;
1274
1275 src = *ppos;
1276 svpfn = src / PM_ENTRY_BYTES;
1277 start_vaddr = svpfn << PAGE_SHIFT;
1278 end_vaddr = TASK_SIZE_OF(task);
1279
1280 /* watch out for wraparound */
1281 if (svpfn > TASK_SIZE_OF(task) >> PAGE_SHIFT)
1282 start_vaddr = end_vaddr;
1283
1284 /*
1285 * The odds are that this will stop walking way
1286 * before end_vaddr, because the length of the
1287 * user buffer is tracked in "pm", and the walk
1288 * will stop when we hit the end of the buffer.
1289 */
1290 ret = 0;
1291 while (count && (start_vaddr < end_vaddr)) {
1292 int len;
1293 unsigned long end;
1294
1295 pm.pos = 0;
1296 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
1297 /* overflow ? */
1298 if (end < start_vaddr || end > end_vaddr)
1299 end = end_vaddr;
1300 down_read(&mm->mmap_sem);
1301 ret = walk_page_range(start_vaddr, end, &pagemap_walk);
1302 up_read(&mm->mmap_sem);
1303 start_vaddr = end;
1304
1305 len = min(count, PM_ENTRY_BYTES * pm.pos);
1306 if (copy_to_user(buf, pm.buffer, len)) {
1307 ret = -EFAULT;
1308 goto out_mm;
1309 }
1310 copied += len;
1311 buf += len;
1312 count -= len;
1313 }
1314 *ppos += copied;
1315 if (!ret || ret == PM_END_OF_BUFFER)
1316 ret = copied;
1317
1318 out_mm:
1319 mmput(mm);
1320 out_free:
1321 kfree(pm.buffer);
1322 out_task:
1323 put_task_struct(task);
1324 out:
1325 return ret;
1326 }
1327
1328 static int pagemap_open(struct inode *inode, struct file *file)
1329 {
1330 /* do not disclose physical addresses: attack vector */
1331 if (!capable(CAP_SYS_ADMIN))
1332 return -EPERM;
1333 pr_warn_once("Bits 55-60 of /proc/PID/pagemap entries are about "
1334 "to stop being page-shift some time soon. See the "
1335 "linux/Documentation/vm/pagemap.txt for details.\n");
1336 return 0;
1337 }
1338
1339 const struct file_operations proc_pagemap_operations = {
1340 .llseek = mem_lseek, /* borrow this */
1341 .read = pagemap_read,
1342 .open = pagemap_open,
1343 };
1344 #endif /* CONFIG_PROC_PAGE_MONITOR */
1345
1346 #ifdef CONFIG_NUMA
1347
1348 struct numa_maps {
1349 unsigned long pages;
1350 unsigned long anon;
1351 unsigned long active;
1352 unsigned long writeback;
1353 unsigned long mapcount_max;
1354 unsigned long dirty;
1355 unsigned long swapcache;
1356 unsigned long node[MAX_NUMNODES];
1357 };
1358
1359 struct numa_maps_private {
1360 struct proc_maps_private proc_maps;
1361 struct numa_maps md;
1362 };
1363
1364 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
1365 unsigned long nr_pages)
1366 {
1367 int count = page_mapcount(page);
1368
1369 md->pages += nr_pages;
1370 if (pte_dirty || PageDirty(page))
1371 md->dirty += nr_pages;
1372
1373 if (PageSwapCache(page))
1374 md->swapcache += nr_pages;
1375
1376 if (PageActive(page) || PageUnevictable(page))
1377 md->active += nr_pages;
1378
1379 if (PageWriteback(page))
1380 md->writeback += nr_pages;
1381
1382 if (PageAnon(page))
1383 md->anon += nr_pages;
1384
1385 if (count > md->mapcount_max)
1386 md->mapcount_max = count;
1387
1388 md->node[page_to_nid(page)] += nr_pages;
1389 }
1390
1391 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
1392 unsigned long addr)
1393 {
1394 struct page *page;
1395 int nid;
1396
1397 if (!pte_present(pte))
1398 return NULL;
1399
1400 page = vm_normal_page(vma, addr, pte);
1401 if (!page)
1402 return NULL;
1403
1404 if (PageReserved(page))
1405 return NULL;
1406
1407 nid = page_to_nid(page);
1408 if (!node_isset(nid, node_states[N_MEMORY]))
1409 return NULL;
1410
1411 return page;
1412 }
1413
1414 static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
1415 unsigned long end, struct mm_walk *walk)
1416 {
1417 struct numa_maps *md = walk->private;
1418 struct vm_area_struct *vma = walk->vma;
1419 spinlock_t *ptl;
1420 pte_t *orig_pte;
1421 pte_t *pte;
1422
1423 if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
1424 pte_t huge_pte = *(pte_t *)pmd;
1425 struct page *page;
1426
1427 page = can_gather_numa_stats(huge_pte, vma, addr);
1428 if (page)
1429 gather_stats(page, md, pte_dirty(huge_pte),
1430 HPAGE_PMD_SIZE/PAGE_SIZE);
1431 spin_unlock(ptl);
1432 return 0;
1433 }
1434
1435 if (pmd_trans_unstable(pmd))
1436 return 0;
1437 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
1438 do {
1439 struct page *page = can_gather_numa_stats(*pte, vma, addr);
1440 if (!page)
1441 continue;
1442 gather_stats(page, md, pte_dirty(*pte), 1);
1443
1444 } while (pte++, addr += PAGE_SIZE, addr != end);
1445 pte_unmap_unlock(orig_pte, ptl);
1446 return 0;
1447 }
1448 #ifdef CONFIG_HUGETLB_PAGE
1449 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1450 unsigned long addr, unsigned long end, struct mm_walk *walk)
1451 {
1452 struct numa_maps *md;
1453 struct page *page;
1454
1455 if (!pte_present(*pte))
1456 return 0;
1457
1458 page = pte_page(*pte);
1459 if (!page)
1460 return 0;
1461
1462 md = walk->private;
1463 gather_stats(page, md, pte_dirty(*pte), 1);
1464 return 0;
1465 }
1466
1467 #else
1468 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1469 unsigned long addr, unsigned long end, struct mm_walk *walk)
1470 {
1471 return 0;
1472 }
1473 #endif
1474
1475 /*
1476 * Display pages allocated per node and memory policy via /proc.
1477 */
1478 static int show_numa_map(struct seq_file *m, void *v, int is_pid)
1479 {
1480 struct numa_maps_private *numa_priv = m->private;
1481 struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
1482 struct vm_area_struct *vma = v;
1483 struct numa_maps *md = &numa_priv->md;
1484 struct file *file = vma->vm_file;
1485 struct mm_struct *mm = vma->vm_mm;
1486 struct mm_walk walk = {
1487 .hugetlb_entry = gather_hugetlb_stats,
1488 .pmd_entry = gather_pte_stats,
1489 .private = md,
1490 .mm = mm,
1491 };
1492 struct mempolicy *pol;
1493 char buffer[64];
1494 int nid;
1495
1496 if (!mm)
1497 return 0;
1498
1499 /* Ensure we start with an empty set of numa_maps statistics. */
1500 memset(md, 0, sizeof(*md));
1501
1502 pol = __get_vma_policy(vma, vma->vm_start);
1503 if (pol) {
1504 mpol_to_str(buffer, sizeof(buffer), pol);
1505 mpol_cond_put(pol);
1506 } else {
1507 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy);
1508 }
1509
1510 seq_printf(m, "%08lx %s", vma->vm_start, buffer);
1511
1512 if (file) {
1513 seq_puts(m, " file=");
1514 seq_file_path(m, file, "\n\t= ");
1515 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1516 seq_puts(m, " heap");
1517 } else {
1518 pid_t tid = pid_of_stack(proc_priv, vma, is_pid);
1519 if (tid != 0) {
1520 /*
1521 * Thread stack in /proc/PID/task/TID/maps or
1522 * the main process stack.
1523 */
1524 if (!is_pid || (vma->vm_start <= mm->start_stack &&
1525 vma->vm_end >= mm->start_stack))
1526 seq_puts(m, " stack");
1527 else
1528 seq_printf(m, " stack:%d", tid);
1529 }
1530 }
1531
1532 if (is_vm_hugetlb_page(vma))
1533 seq_puts(m, " huge");
1534
1535 /* mmap_sem is held by m_start */
1536 walk_page_vma(vma, &walk);
1537
1538 if (!md->pages)
1539 goto out;
1540
1541 if (md->anon)
1542 seq_printf(m, " anon=%lu", md->anon);
1543
1544 if (md->dirty)
1545 seq_printf(m, " dirty=%lu", md->dirty);
1546
1547 if (md->pages != md->anon && md->pages != md->dirty)
1548 seq_printf(m, " mapped=%lu", md->pages);
1549
1550 if (md->mapcount_max > 1)
1551 seq_printf(m, " mapmax=%lu", md->mapcount_max);
1552
1553 if (md->swapcache)
1554 seq_printf(m, " swapcache=%lu", md->swapcache);
1555
1556 if (md->active < md->pages && !is_vm_hugetlb_page(vma))
1557 seq_printf(m, " active=%lu", md->active);
1558
1559 if (md->writeback)
1560 seq_printf(m, " writeback=%lu", md->writeback);
1561
1562 for_each_node_state(nid, N_MEMORY)
1563 if (md->node[nid])
1564 seq_printf(m, " N%d=%lu", nid, md->node[nid]);
1565
1566 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10);
1567 out:
1568 seq_putc(m, '\n');
1569 m_cache_vma(m, vma);
1570 return 0;
1571 }
1572
1573 static int show_pid_numa_map(struct seq_file *m, void *v)
1574 {
1575 return show_numa_map(m, v, 1);
1576 }
1577
1578 static int show_tid_numa_map(struct seq_file *m, void *v)
1579 {
1580 return show_numa_map(m, v, 0);
1581 }
1582
1583 static const struct seq_operations proc_pid_numa_maps_op = {
1584 .start = m_start,
1585 .next = m_next,
1586 .stop = m_stop,
1587 .show = show_pid_numa_map,
1588 };
1589
1590 static const struct seq_operations proc_tid_numa_maps_op = {
1591 .start = m_start,
1592 .next = m_next,
1593 .stop = m_stop,
1594 .show = show_tid_numa_map,
1595 };
1596
1597 static int numa_maps_open(struct inode *inode, struct file *file,
1598 const struct seq_operations *ops)
1599 {
1600 return proc_maps_open(inode, file, ops,
1601 sizeof(struct numa_maps_private));
1602 }
1603
1604 static int pid_numa_maps_open(struct inode *inode, struct file *file)
1605 {
1606 return numa_maps_open(inode, file, &proc_pid_numa_maps_op);
1607 }
1608
1609 static int tid_numa_maps_open(struct inode *inode, struct file *file)
1610 {
1611 return numa_maps_open(inode, file, &proc_tid_numa_maps_op);
1612 }
1613
1614 const struct file_operations proc_pid_numa_maps_operations = {
1615 .open = pid_numa_maps_open,
1616 .read = seq_read,
1617 .llseek = seq_lseek,
1618 .release = proc_map_release,
1619 };
1620
1621 const struct file_operations proc_tid_numa_maps_operations = {
1622 .open = tid_numa_maps_open,
1623 .read = seq_read,
1624 .llseek = seq_lseek,
1625 .release = proc_map_release,
1626 };
1627 #endif /* CONFIG_NUMA */
Linux kernel - Deliverables
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