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mm/gup_benchmark: fix unsigned comparison to zero in __gup_benchmark_ioctl
[linux/fpc-iii.git] / fs / proc / task_mmu.c
blob5ea1d64cb0b4c19c185ad67d5990c0ce03e82561
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/mm.h>
3 #include <linux/vmacache.h>
4 #include <linux/hugetlb.h>
5 #include <linux/huge_mm.h>
6 #include <linux/mount.h>
7 #include <linux/seq_file.h>
8 #include <linux/highmem.h>
9 #include <linux/ptrace.h>
10 #include <linux/slab.h>
11 #include <linux/pagemap.h>
12 #include <linux/mempolicy.h>
13 #include <linux/rmap.h>
14 #include <linux/swap.h>
15 #include <linux/sched/mm.h>
16 #include <linux/swapops.h>
17 #include <linux/mmu_notifier.h>
18 #include <linux/page_idle.h>
19 #include <linux/shmem_fs.h>
20 #include <linux/uaccess.h>
21 #include <linux/pkeys.h>
22
23 #include <asm/elf.h>
24 #include <asm/tlb.h>
25 #include <asm/tlbflush.h>
26 #include "internal.h"
27
28 #define SEQ_PUT_DEC(str, val) \
29 seq_put_decimal_ull_width(m, str, (val) << (PAGE_SHIFT-10), 8)
30 void task_mem(struct seq_file *m, struct mm_struct *mm)
31 {
32 unsigned long text, lib, swap, anon, file, shmem;
33 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
34
35 anon = get_mm_counter(mm, MM_ANONPAGES);
36 file = get_mm_counter(mm, MM_FILEPAGES);
37 shmem = get_mm_counter(mm, MM_SHMEMPAGES);
38
39 /*
40 * Note: to minimize their overhead, mm maintains hiwater_vm and
41 * hiwater_rss only when about to *lower* total_vm or rss. Any
42 * collector of these hiwater stats must therefore get total_vm
43 * and rss too, which will usually be the higher. Barriers? not
44 * worth the effort, such snapshots can always be inconsistent.
45 */
46 hiwater_vm = total_vm = mm->total_vm;
47 if (hiwater_vm < mm->hiwater_vm)
48 hiwater_vm = mm->hiwater_vm;
49 hiwater_rss = total_rss = anon + file + shmem;
50 if (hiwater_rss < mm->hiwater_rss)
51 hiwater_rss = mm->hiwater_rss;
52
53 /* split executable areas between text and lib */
54 text = PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK);
55 text = min(text, mm->exec_vm << PAGE_SHIFT);
56 lib = (mm->exec_vm << PAGE_SHIFT) - text;
57
58 swap = get_mm_counter(mm, MM_SWAPENTS);
59 SEQ_PUT_DEC("VmPeak:\t", hiwater_vm);
60 SEQ_PUT_DEC(" kB\nVmSize:\t", total_vm);
61 SEQ_PUT_DEC(" kB\nVmLck:\t", mm->locked_vm);
62 SEQ_PUT_DEC(" kB\nVmPin:\t", mm->pinned_vm);
63 SEQ_PUT_DEC(" kB\nVmHWM:\t", hiwater_rss);
64 SEQ_PUT_DEC(" kB\nVmRSS:\t", total_rss);
65 SEQ_PUT_DEC(" kB\nRssAnon:\t", anon);
66 SEQ_PUT_DEC(" kB\nRssFile:\t", file);
67 SEQ_PUT_DEC(" kB\nRssShmem:\t", shmem);
68 SEQ_PUT_DEC(" kB\nVmData:\t", mm->data_vm);
69 SEQ_PUT_DEC(" kB\nVmStk:\t", mm->stack_vm);
70 seq_put_decimal_ull_width(m,
71 " kB\nVmExe:\t", text >> 10, 8);
72 seq_put_decimal_ull_width(m,
73 " kB\nVmLib:\t", lib >> 10, 8);
74 seq_put_decimal_ull_width(m,
75 " kB\nVmPTE:\t", mm_pgtables_bytes(mm) >> 10, 8);
76 SEQ_PUT_DEC(" kB\nVmSwap:\t", swap);
77 seq_puts(m, " kB\n");
78 hugetlb_report_usage(m, mm);
79 }
80 #undef SEQ_PUT_DEC
81
82 unsigned long task_vsize(struct mm_struct *mm)
83 {
84 return PAGE_SIZE * mm->total_vm;
85 }
86
87 unsigned long task_statm(struct mm_struct *mm,
88 unsigned long *shared, unsigned long *text,
89 unsigned long *data, unsigned long *resident)
90 {
91 *shared = get_mm_counter(mm, MM_FILEPAGES) +
92 get_mm_counter(mm, MM_SHMEMPAGES);
93 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
94 >> PAGE_SHIFT;
95 *data = mm->data_vm + mm->stack_vm;
96 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
97 return mm->total_vm;
98 }
99
100 #ifdef CONFIG_NUMA
101 /*
102 * Save get_task_policy() for show_numa_map().
103 */
104 static void hold_task_mempolicy(struct proc_maps_private *priv)
105 {
106 struct task_struct *task = priv->task;
107
108 task_lock(task);
109 priv->task_mempolicy = get_task_policy(task);
110 mpol_get(priv->task_mempolicy);
111 task_unlock(task);
112 }
113 static void release_task_mempolicy(struct proc_maps_private *priv)
114 {
115 mpol_put(priv->task_mempolicy);
116 }
117 #else
118 static void hold_task_mempolicy(struct proc_maps_private *priv)
119 {
120 }
121 static void release_task_mempolicy(struct proc_maps_private *priv)
122 {
123 }
124 #endif
125
126 static void vma_stop(struct proc_maps_private *priv)
127 {
128 struct mm_struct *mm = priv->mm;
129
130 release_task_mempolicy(priv);
131 up_read(&mm->mmap_sem);
132 mmput(mm);
133 }
134
135 static struct vm_area_struct *
136 m_next_vma(struct proc_maps_private *priv, struct vm_area_struct *vma)
137 {
138 if (vma == priv->tail_vma)
139 return NULL;
140 return vma->vm_next ?: priv->tail_vma;
141 }
142
143 static void m_cache_vma(struct seq_file *m, struct vm_area_struct *vma)
144 {
145 if (m->count < m->size) /* vma is copied successfully */
146 m->version = m_next_vma(m->private, vma) ? vma->vm_end : -1UL;
147 }
148
149 static void *m_start(struct seq_file *m, loff_t *ppos)
150 {
151 struct proc_maps_private *priv = m->private;
152 unsigned long last_addr = m->version;
153 struct mm_struct *mm;
154 struct vm_area_struct *vma;
155 unsigned int pos = *ppos;
156
157 /* See m_cache_vma(). Zero at the start or after lseek. */
158 if (last_addr == -1UL)
159 return NULL;
160
161 priv->task = get_proc_task(priv->inode);
162 if (!priv->task)
163 return ERR_PTR(-ESRCH);
164
165 mm = priv->mm;
166 if (!mm || !mmget_not_zero(mm))
167 return NULL;
168
169 down_read(&mm->mmap_sem);
170 hold_task_mempolicy(priv);
171 priv->tail_vma = get_gate_vma(mm);
172
173 if (last_addr) {
174 vma = find_vma(mm, last_addr - 1);
175 if (vma && vma->vm_start <= last_addr)
176 vma = m_next_vma(priv, vma);
177 if (vma)
178 return vma;
179 }
180
181 m->version = 0;
182 if (pos < mm->map_count) {
183 for (vma = mm->mmap; pos; pos--) {
184 m->version = vma->vm_start;
185 vma = vma->vm_next;
186 }
187 return vma;
188 }
189
190 /* we do not bother to update m->version in this case */
191 if (pos == mm->map_count && priv->tail_vma)
192 return priv->tail_vma;
193
194 vma_stop(priv);
195 return NULL;
196 }
197
198 static void *m_next(struct seq_file *m, void *v, loff_t *pos)
199 {
200 struct proc_maps_private *priv = m->private;
201 struct vm_area_struct *next;
202
203 (*pos)++;
204 next = m_next_vma(priv, v);
205 if (!next)
206 vma_stop(priv);
207 return next;
208 }
209
210 static void m_stop(struct seq_file *m, void *v)
211 {
212 struct proc_maps_private *priv = m->private;
213
214 if (!IS_ERR_OR_NULL(v))
215 vma_stop(priv);
216 if (priv->task) {
217 put_task_struct(priv->task);
218 priv->task = NULL;
219 }
220 }
221
222 static int proc_maps_open(struct inode *inode, struct file *file,
223 const struct seq_operations *ops, int psize)
224 {
225 struct proc_maps_private *priv = __seq_open_private(file, ops, psize);
226
227 if (!priv)
228 return -ENOMEM;
229
230 priv->inode = inode;
231 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
232 if (IS_ERR(priv->mm)) {
233 int err = PTR_ERR(priv->mm);
234
235 seq_release_private(inode, file);
236 return err;
237 }
238
239 return 0;
240 }
241
242 static int proc_map_release(struct inode *inode, struct file *file)
243 {
244 struct seq_file *seq = file->private_data;
245 struct proc_maps_private *priv = seq->private;
246
247 if (priv->mm)
248 mmdrop(priv->mm);
249
250 return seq_release_private(inode, file);
251 }
252
253 static int do_maps_open(struct inode *inode, struct file *file,
254 const struct seq_operations *ops)
255 {
256 return proc_maps_open(inode, file, ops,
257 sizeof(struct proc_maps_private));
258 }
259
260 /*
261 * Indicate if the VMA is a stack for the given task; for
262 * /proc/PID/maps that is the stack of the main task.
263 */
264 static int is_stack(struct vm_area_struct *vma)
265 {
266 /*
267 * We make no effort to guess what a given thread considers to be
268 * its "stack". It's not even well-defined for programs written
269 * languages like Go.
270 */
271 return vma->vm_start <= vma->vm_mm->start_stack &&
272 vma->vm_end >= vma->vm_mm->start_stack;
273 }
274
275 static void show_vma_header_prefix(struct seq_file *m,
276 unsigned long start, unsigned long end,
277 vm_flags_t flags, unsigned long long pgoff,
278 dev_t dev, unsigned long ino)
279 {
280 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
281 seq_put_hex_ll(m, NULL, start, 8);
282 seq_put_hex_ll(m, "-", end, 8);
283 seq_putc(m, ' ');
284 seq_putc(m, flags & VM_READ ? 'r' : '-');
285 seq_putc(m, flags & VM_WRITE ? 'w' : '-');
286 seq_putc(m, flags & VM_EXEC ? 'x' : '-');
287 seq_putc(m, flags & VM_MAYSHARE ? 's' : 'p');
288 seq_put_hex_ll(m, " ", pgoff, 8);
289 seq_put_hex_ll(m, " ", MAJOR(dev), 2);
290 seq_put_hex_ll(m, ":", MINOR(dev), 2);
291 seq_put_decimal_ull(m, " ", ino);
292 seq_putc(m, ' ');
293 }
294
295 static void
296 show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
297 {
298 struct mm_struct *mm = vma->vm_mm;
299 struct file *file = vma->vm_file;
300 vm_flags_t flags = vma->vm_flags;
301 unsigned long ino = 0;
302 unsigned long long pgoff = 0;
303 unsigned long start, end;
304 dev_t dev = 0;
305 const char *name = NULL;
306
307 if (file) {
308 struct inode *inode = file_inode(vma->vm_file);
309 dev = inode->i_sb->s_dev;
310 ino = inode->i_ino;
311 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
312 }
313
314 start = vma->vm_start;
315 end = vma->vm_end;
316 show_vma_header_prefix(m, start, end, flags, pgoff, dev, ino);
317
318 /*
319 * Print the dentry name for named mappings, and a
320 * special [heap] marker for the heap:
321 */
322 if (file) {
323 seq_pad(m, ' ');
324 seq_file_path(m, file, "\n");
325 goto done;
326 }
327
328 if (vma->vm_ops && vma->vm_ops->name) {
329 name = vma->vm_ops->name(vma);
330 if (name)
331 goto done;
332 }
333
334 name = arch_vma_name(vma);
335 if (!name) {
336 if (!mm) {
337 name = "[vdso]";
338 goto done;
339 }
340
341 if (vma->vm_start <= mm->brk &&
342 vma->vm_end >= mm->start_brk) {
343 name = "[heap]";
344 goto done;
345 }
346
347 if (is_stack(vma))
348 name = "[stack]";
349 }
350
351 done:
352 if (name) {
353 seq_pad(m, ' ');
354 seq_puts(m, name);
355 }
356 seq_putc(m, '\n');
357 }
358
359 static int show_map(struct seq_file *m, void *v)
360 {
361 show_map_vma(m, v);
362 m_cache_vma(m, v);
363 return 0;
364 }
365
366 static const struct seq_operations proc_pid_maps_op = {
367 .start = m_start,
368 .next = m_next,
369 .stop = m_stop,
370 .show = show_map
371 };
372
373 static int pid_maps_open(struct inode *inode, struct file *file)
374 {
375 return do_maps_open(inode, file, &proc_pid_maps_op);
376 }
377
378 const struct file_operations proc_pid_maps_operations = {
379 .open = pid_maps_open,
380 .read = seq_read,
381 .llseek = seq_lseek,
382 .release = proc_map_release,
383 };
384
385 /*
386 * Proportional Set Size(PSS): my share of RSS.
387 *
388 * PSS of a process is the count of pages it has in memory, where each
389 * page is divided by the number of processes sharing it. So if a
390 * process has 1000 pages all to itself, and 1000 shared with one other
391 * process, its PSS will be 1500.
392 *
393 * To keep (accumulated) division errors low, we adopt a 64bit
394 * fixed-point pss counter to minimize division errors. So (pss >>
395 * PSS_SHIFT) would be the real byte count.
396 *
397 * A shift of 12 before division means (assuming 4K page size):
398 * - 1M 3-user-pages add up to 8KB errors;
399 * - supports mapcount up to 2^24, or 16M;
400 * - supports PSS up to 2^52 bytes, or 4PB.
401 */
402 #define PSS_SHIFT 12
403
404 #ifdef CONFIG_PROC_PAGE_MONITOR
405 struct mem_size_stats {
406 unsigned long resident;
407 unsigned long shared_clean;
408 unsigned long shared_dirty;
409 unsigned long private_clean;
410 unsigned long private_dirty;
411 unsigned long referenced;
412 unsigned long anonymous;
413 unsigned long lazyfree;
414 unsigned long anonymous_thp;
415 unsigned long shmem_thp;
416 unsigned long swap;
417 unsigned long shared_hugetlb;
418 unsigned long private_hugetlb;
419 u64 pss;
420 u64 pss_locked;
421 u64 swap_pss;
422 bool check_shmem_swap;
423 };
424
425 static void smaps_account(struct mem_size_stats *mss, struct page *page,
426 bool compound, bool young, bool dirty)
427 {
428 int i, nr = compound ? 1 << compound_order(page) : 1;
429 unsigned long size = nr * PAGE_SIZE;
430
431 if (PageAnon(page)) {
432 mss->anonymous += size;
433 if (!PageSwapBacked(page) && !dirty && !PageDirty(page))
434 mss->lazyfree += size;
435 }
436
437 mss->resident += size;
438 /* Accumulate the size in pages that have been accessed. */
439 if (young || page_is_young(page) || PageReferenced(page))
440 mss->referenced += size;
441
442 /*
443 * page_count(page) == 1 guarantees the page is mapped exactly once.
444 * If any subpage of the compound page mapped with PTE it would elevate
445 * page_count().
446 */
447 if (page_count(page) == 1) {
448 if (dirty || PageDirty(page))
449 mss->private_dirty += size;
450 else
451 mss->private_clean += size;
452 mss->pss += (u64)size << PSS_SHIFT;
453 return;
454 }
455
456 for (i = 0; i < nr; i++, page++) {
457 int mapcount = page_mapcount(page);
458
459 if (mapcount >= 2) {
460 if (dirty || PageDirty(page))
461 mss->shared_dirty += PAGE_SIZE;
462 else
463 mss->shared_clean += PAGE_SIZE;
464 mss->pss += (PAGE_SIZE << PSS_SHIFT) / mapcount;
465 } else {
466 if (dirty || PageDirty(page))
467 mss->private_dirty += PAGE_SIZE;
468 else
469 mss->private_clean += PAGE_SIZE;
470 mss->pss += PAGE_SIZE << PSS_SHIFT;
471 }
472 }
473 }
474
475 #ifdef CONFIG_SHMEM
476 static int smaps_pte_hole(unsigned long addr, unsigned long end,
477 struct mm_walk *walk)
478 {
479 struct mem_size_stats *mss = walk->private;
480
481 mss->swap += shmem_partial_swap_usage(
482 walk->vma->vm_file->f_mapping, addr, end);
483
484 return 0;
485 }
486 #endif
487
488 static void smaps_pte_entry(pte_t *pte, unsigned long addr,
489 struct mm_walk *walk)
490 {
491 struct mem_size_stats *mss = walk->private;
492 struct vm_area_struct *vma = walk->vma;
493 struct page *page = NULL;
494
495 if (pte_present(*pte)) {
496 page = vm_normal_page(vma, addr, *pte);
497 } else if (is_swap_pte(*pte)) {
498 swp_entry_t swpent = pte_to_swp_entry(*pte);
499
500 if (!non_swap_entry(swpent)) {
501 int mapcount;
502
503 mss->swap += PAGE_SIZE;
504 mapcount = swp_swapcount(swpent);
505 if (mapcount >= 2) {
506 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT;
507
508 do_div(pss_delta, mapcount);
509 mss->swap_pss += pss_delta;
510 } else {
511 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT;
512 }
513 } else if (is_migration_entry(swpent))
514 page = migration_entry_to_page(swpent);
515 else if (is_device_private_entry(swpent))
516 page = device_private_entry_to_page(swpent);
517 } else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap
518 && pte_none(*pte))) {
519 page = find_get_entry(vma->vm_file->f_mapping,
520 linear_page_index(vma, addr));
521 if (!page)
522 return;
523
524 if (radix_tree_exceptional_entry(page))
525 mss->swap += PAGE_SIZE;
526 else
527 put_page(page);
528
529 return;
530 }
531
532 if (!page)
533 return;
534
535 smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte));
536 }
537
538 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
539 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
540 struct mm_walk *walk)
541 {
542 struct mem_size_stats *mss = walk->private;
543 struct vm_area_struct *vma = walk->vma;
544 struct page *page;
545
546 /* FOLL_DUMP will return -EFAULT on huge zero page */
547 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
548 if (IS_ERR_OR_NULL(page))
549 return;
550 if (PageAnon(page))
551 mss->anonymous_thp += HPAGE_PMD_SIZE;
552 else if (PageSwapBacked(page))
553 mss->shmem_thp += HPAGE_PMD_SIZE;
554 else if (is_zone_device_page(page))
555 /* pass */;
556 else
557 VM_BUG_ON_PAGE(1, page);
558 smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd));
559 }
560 #else
561 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
562 struct mm_walk *walk)
563 {
564 }
565 #endif
566
567 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
568 struct mm_walk *walk)
569 {
570 struct vm_area_struct *vma = walk->vma;
571 pte_t *pte;
572 spinlock_t *ptl;
573
574 ptl = pmd_trans_huge_lock(pmd, vma);
575 if (ptl) {
576 if (pmd_present(*pmd))
577 smaps_pmd_entry(pmd, addr, walk);
578 spin_unlock(ptl);
579 goto out;
580 }
581
582 if (pmd_trans_unstable(pmd))
583 goto out;
584 /*
585 * The mmap_sem held all the way back in m_start() is what
586 * keeps khugepaged out of here and from collapsing things
587 * in here.
588 */
589 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
590 for (; addr != end; pte++, addr += PAGE_SIZE)
591 smaps_pte_entry(pte, addr, walk);
592 pte_unmap_unlock(pte - 1, ptl);
593 out:
594 cond_resched();
595 return 0;
596 }
597
598 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
599 {
600 /*
601 * Don't forget to update Documentation/ on changes.
602 */
603 static const char mnemonics[BITS_PER_LONG][2] = {
604 /*
605 * In case if we meet a flag we don't know about.
606 */
607 [0 ... (BITS_PER_LONG-1)] = "??",
608
609 [ilog2(VM_READ)] = "rd",
610 [ilog2(VM_WRITE)] = "wr",
611 [ilog2(VM_EXEC)] = "ex",
612 [ilog2(VM_SHARED)] = "sh",
613 [ilog2(VM_MAYREAD)] = "mr",
614 [ilog2(VM_MAYWRITE)] = "mw",
615 [ilog2(VM_MAYEXEC)] = "me",
616 [ilog2(VM_MAYSHARE)] = "ms",
617 [ilog2(VM_GROWSDOWN)] = "gd",
618 [ilog2(VM_PFNMAP)] = "pf",
619 [ilog2(VM_DENYWRITE)] = "dw",
620 #ifdef CONFIG_X86_INTEL_MPX
621 [ilog2(VM_MPX)] = "mp",
622 #endif
623 [ilog2(VM_LOCKED)] = "lo",
624 [ilog2(VM_IO)] = "io",
625 [ilog2(VM_SEQ_READ)] = "sr",
626 [ilog2(VM_RAND_READ)] = "rr",
627 [ilog2(VM_DONTCOPY)] = "dc",
628 [ilog2(VM_DONTEXPAND)] = "de",
629 [ilog2(VM_ACCOUNT)] = "ac",
630 [ilog2(VM_NORESERVE)] = "nr",
631 [ilog2(VM_HUGETLB)] = "ht",
632 [ilog2(VM_SYNC)] = "sf",
633 [ilog2(VM_ARCH_1)] = "ar",
634 [ilog2(VM_WIPEONFORK)] = "wf",
635 [ilog2(VM_DONTDUMP)] = "dd",
636 #ifdef CONFIG_MEM_SOFT_DIRTY
637 [ilog2(VM_SOFTDIRTY)] = "sd",
638 #endif
639 [ilog2(VM_MIXEDMAP)] = "mm",
640 [ilog2(VM_HUGEPAGE)] = "hg",
641 [ilog2(VM_NOHUGEPAGE)] = "nh",
642 [ilog2(VM_MERGEABLE)] = "mg",
643 [ilog2(VM_UFFD_MISSING)]= "um",
644 [ilog2(VM_UFFD_WP)] = "uw",
645 #ifdef CONFIG_ARCH_HAS_PKEYS
646 /* These come out via ProtectionKey: */
647 [ilog2(VM_PKEY_BIT0)] = "",
648 [ilog2(VM_PKEY_BIT1)] = "",
649 [ilog2(VM_PKEY_BIT2)] = "",
650 [ilog2(VM_PKEY_BIT3)] = "",
651 #if VM_PKEY_BIT4
652 [ilog2(VM_PKEY_BIT4)] = "",
653 #endif
654 #endif /* CONFIG_ARCH_HAS_PKEYS */
655 };
656 size_t i;
657
658 seq_puts(m, "VmFlags: ");
659 for (i = 0; i < BITS_PER_LONG; i++) {
660 if (!mnemonics[i][0])
661 continue;
662 if (vma->vm_flags & (1UL << i)) {
663 seq_putc(m, mnemonics[i][0]);
664 seq_putc(m, mnemonics[i][1]);
665 seq_putc(m, ' ');
666 }
667 }
668 seq_putc(m, '\n');
669 }
670
671 #ifdef CONFIG_HUGETLB_PAGE
672 static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,
673 unsigned long addr, unsigned long end,
674 struct mm_walk *walk)
675 {
676 struct mem_size_stats *mss = walk->private;
677 struct vm_area_struct *vma = walk->vma;
678 struct page *page = NULL;
679
680 if (pte_present(*pte)) {
681 page = vm_normal_page(vma, addr, *pte);
682 } else if (is_swap_pte(*pte)) {
683 swp_entry_t swpent = pte_to_swp_entry(*pte);
684
685 if (is_migration_entry(swpent))
686 page = migration_entry_to_page(swpent);
687 else if (is_device_private_entry(swpent))
688 page = device_private_entry_to_page(swpent);
689 }
690 if (page) {
691 int mapcount = page_mapcount(page);
692
693 if (mapcount >= 2)
694 mss->shared_hugetlb += huge_page_size(hstate_vma(vma));
695 else
696 mss->private_hugetlb += huge_page_size(hstate_vma(vma));
697 }
698 return 0;
699 }
700 #endif /* HUGETLB_PAGE */
701
702 static void smap_gather_stats(struct vm_area_struct *vma,
703 struct mem_size_stats *mss)
704 {
705 struct mm_walk smaps_walk = {
706 .pmd_entry = smaps_pte_range,
707 #ifdef CONFIG_HUGETLB_PAGE
708 .hugetlb_entry = smaps_hugetlb_range,
709 #endif
710 .mm = vma->vm_mm,
711 };
712
713 smaps_walk.private = mss;
714
715 #ifdef CONFIG_SHMEM
716 if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) {
717 /*
718 * For shared or readonly shmem mappings we know that all
719 * swapped out pages belong to the shmem object, and we can
720 * obtain the swap value much more efficiently. For private
721 * writable mappings, we might have COW pages that are
722 * not affected by the parent swapped out pages of the shmem
723 * object, so we have to distinguish them during the page walk.
724 * Unless we know that the shmem object (or the part mapped by
725 * our VMA) has no swapped out pages at all.
726 */
727 unsigned long shmem_swapped = shmem_swap_usage(vma);
728
729 if (!shmem_swapped || (vma->vm_flags & VM_SHARED) ||
730 !(vma->vm_flags & VM_WRITE)) {
731 mss->swap = shmem_swapped;
732 } else {
733 mss->check_shmem_swap = true;
734 smaps_walk.pte_hole = smaps_pte_hole;
735 }
736 }
737 #endif
738
739 /* mmap_sem is held in m_start */
740 walk_page_vma(vma, &smaps_walk);
741 if (vma->vm_flags & VM_LOCKED)
742 mss->pss_locked += mss->pss;
743 }
744
745 #define SEQ_PUT_DEC(str, val) \
746 seq_put_decimal_ull_width(m, str, (val) >> 10, 8)
747
748 /* Show the contents common for smaps and smaps_rollup */
749 static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss)
750 {
751 SEQ_PUT_DEC("Rss: ", mss->resident);
752 SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT);
753 SEQ_PUT_DEC(" kB\nShared_Clean: ", mss->shared_clean);
754 SEQ_PUT_DEC(" kB\nShared_Dirty: ", mss->shared_dirty);
755 SEQ_PUT_DEC(" kB\nPrivate_Clean: ", mss->private_clean);
756 SEQ_PUT_DEC(" kB\nPrivate_Dirty: ", mss->private_dirty);
757 SEQ_PUT_DEC(" kB\nReferenced: ", mss->referenced);
758 SEQ_PUT_DEC(" kB\nAnonymous: ", mss->anonymous);
759 SEQ_PUT_DEC(" kB\nLazyFree: ", mss->lazyfree);
760 SEQ_PUT_DEC(" kB\nAnonHugePages: ", mss->anonymous_thp);
761 SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp);
762 SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb);
763 seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ",
764 mss->private_hugetlb >> 10, 7);
765 SEQ_PUT_DEC(" kB\nSwap: ", mss->swap);
766 SEQ_PUT_DEC(" kB\nSwapPss: ",
767 mss->swap_pss >> PSS_SHIFT);
768 SEQ_PUT_DEC(" kB\nLocked: ",
769 mss->pss_locked >> PSS_SHIFT);
770 seq_puts(m, " kB\n");
771 }
772
773 static int show_smap(struct seq_file *m, void *v)
774 {
775 struct vm_area_struct *vma = v;
776 struct mem_size_stats mss;
777
778 memset(&mss, 0, sizeof(mss));
779
780 smap_gather_stats(vma, &mss);
781
782 show_map_vma(m, vma);
783
784 SEQ_PUT_DEC("Size: ", vma->vm_end - vma->vm_start);
785 SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma));
786 SEQ_PUT_DEC(" kB\nMMUPageSize: ", vma_mmu_pagesize(vma));
787 seq_puts(m, " kB\n");
788
789 __show_smap(m, &mss);
790
791 if (arch_pkeys_enabled())
792 seq_printf(m, "ProtectionKey: %8u\n", vma_pkey(vma));
793 show_smap_vma_flags(m, vma);
794
795 m_cache_vma(m, vma);
796
797 return 0;
798 }
799
800 static int show_smaps_rollup(struct seq_file *m, void *v)
801 {
802 struct proc_maps_private *priv = m->private;
803 struct mem_size_stats mss;
804 struct mm_struct *mm;
805 struct vm_area_struct *vma;
806 unsigned long last_vma_end = 0;
807 int ret = 0;
808
809 priv->task = get_proc_task(priv->inode);
810 if (!priv->task)
811 return -ESRCH;
812
813 mm = priv->mm;
814 if (!mm || !mmget_not_zero(mm)) {
815 ret = -ESRCH;
816 goto out_put_task;
817 }
818
819 memset(&mss, 0, sizeof(mss));
820
821 down_read(&mm->mmap_sem);
822 hold_task_mempolicy(priv);
823
824 for (vma = priv->mm->mmap; vma; vma = vma->vm_next) {
825 smap_gather_stats(vma, &mss);
826 last_vma_end = vma->vm_end;
827 }
828
829 show_vma_header_prefix(m, priv->mm->mmap->vm_start,
830 last_vma_end, 0, 0, 0, 0);
831 seq_pad(m, ' ');
832 seq_puts(m, "[rollup]\n");
833
834 __show_smap(m, &mss);
835
836 release_task_mempolicy(priv);
837 up_read(&mm->mmap_sem);
838 mmput(mm);
839
840 out_put_task:
841 put_task_struct(priv->task);
842 priv->task = NULL;
843
844 return ret;
845 }
846 #undef SEQ_PUT_DEC
847
848 static const struct seq_operations proc_pid_smaps_op = {
849 .start = m_start,
850 .next = m_next,
851 .stop = m_stop,
852 .show = show_smap
853 };
854
855 static int pid_smaps_open(struct inode *inode, struct file *file)
856 {
857 return do_maps_open(inode, file, &proc_pid_smaps_op);
858 }
859
860 static int smaps_rollup_open(struct inode *inode, struct file *file)
861 {
862 int ret;
863 struct proc_maps_private *priv;
864
865 priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT);
866 if (!priv)
867 return -ENOMEM;
868
869 ret = single_open(file, show_smaps_rollup, priv);
870 if (ret)
871 goto out_free;
872
873 priv->inode = inode;
874 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
875 if (IS_ERR(priv->mm)) {
876 ret = PTR_ERR(priv->mm);
877
878 single_release(inode, file);
879 goto out_free;
880 }
881
882 return 0;
883
884 out_free:
885 kfree(priv);
886 return ret;
887 }
888
889 static int smaps_rollup_release(struct inode *inode, struct file *file)
890 {
891 struct seq_file *seq = file->private_data;
892 struct proc_maps_private *priv = seq->private;
893
894 if (priv->mm)
895 mmdrop(priv->mm);
896
897 kfree(priv);
898 return single_release(inode, file);
899 }
900
901 const struct file_operations proc_pid_smaps_operations = {
902 .open = pid_smaps_open,
903 .read = seq_read,
904 .llseek = seq_lseek,
905 .release = proc_map_release,
906 };
907
908 const struct file_operations proc_pid_smaps_rollup_operations = {
909 .open = smaps_rollup_open,
910 .read = seq_read,
911 .llseek = seq_lseek,
912 .release = smaps_rollup_release,
913 };
914
915 enum clear_refs_types {
916 CLEAR_REFS_ALL = 1,
917 CLEAR_REFS_ANON,
918 CLEAR_REFS_MAPPED,
919 CLEAR_REFS_SOFT_DIRTY,
920 CLEAR_REFS_MM_HIWATER_RSS,
921 CLEAR_REFS_LAST,
922 };
923
924 struct clear_refs_private {
925 enum clear_refs_types type;
926 };
927
928 #ifdef CONFIG_MEM_SOFT_DIRTY
929 static inline void clear_soft_dirty(struct vm_area_struct *vma,
930 unsigned long addr, pte_t *pte)
931 {
932 /*
933 * The soft-dirty tracker uses #PF-s to catch writes
934 * to pages, so write-protect the pte as well. See the
935 * Documentation/admin-guide/mm/soft-dirty.rst for full description
936 * of how soft-dirty works.
937 */
938 pte_t ptent = *pte;
939
940 if (pte_present(ptent)) {
941 ptent = ptep_modify_prot_start(vma->vm_mm, addr, pte);
942 ptent = pte_wrprotect(ptent);
943 ptent = pte_clear_soft_dirty(ptent);
944 ptep_modify_prot_commit(vma->vm_mm, addr, pte, ptent);
945 } else if (is_swap_pte(ptent)) {
946 ptent = pte_swp_clear_soft_dirty(ptent);
947 set_pte_at(vma->vm_mm, addr, pte, ptent);
948 }
949 }
950 #else
951 static inline void clear_soft_dirty(struct vm_area_struct *vma,
952 unsigned long addr, pte_t *pte)
953 {
954 }
955 #endif
956
957 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
958 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
959 unsigned long addr, pmd_t *pmdp)
960 {
961 pmd_t old, pmd = *pmdp;
962
963 if (pmd_present(pmd)) {
964 /* See comment in change_huge_pmd() */
965 old = pmdp_invalidate(vma, addr, pmdp);
966 if (pmd_dirty(old))
967 pmd = pmd_mkdirty(pmd);
968 if (pmd_young(old))
969 pmd = pmd_mkyoung(pmd);
970
971 pmd = pmd_wrprotect(pmd);
972 pmd = pmd_clear_soft_dirty(pmd);
973
974 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
975 } else if (is_migration_entry(pmd_to_swp_entry(pmd))) {
976 pmd = pmd_swp_clear_soft_dirty(pmd);
977 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
978 }
979 }
980 #else
981 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
982 unsigned long addr, pmd_t *pmdp)
983 {
984 }
985 #endif
986
987 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
988 unsigned long end, struct mm_walk *walk)
989 {
990 struct clear_refs_private *cp = walk->private;
991 struct vm_area_struct *vma = walk->vma;
992 pte_t *pte, ptent;
993 spinlock_t *ptl;
994 struct page *page;
995
996 ptl = pmd_trans_huge_lock(pmd, vma);
997 if (ptl) {
998 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
999 clear_soft_dirty_pmd(vma, addr, pmd);
1000 goto out;
1001 }
1002
1003 if (!pmd_present(*pmd))
1004 goto out;
1005
1006 page = pmd_page(*pmd);
1007
1008 /* Clear accessed and referenced bits. */
1009 pmdp_test_and_clear_young(vma, addr, pmd);
1010 test_and_clear_page_young(page);
1011 ClearPageReferenced(page);
1012 out:
1013 spin_unlock(ptl);
1014 return 0;
1015 }
1016
1017 if (pmd_trans_unstable(pmd))
1018 return 0;
1019
1020 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
1021 for (; addr != end; pte++, addr += PAGE_SIZE) {
1022 ptent = *pte;
1023
1024 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
1025 clear_soft_dirty(vma, addr, pte);
1026 continue;
1027 }
1028
1029 if (!pte_present(ptent))
1030 continue;
1031
1032 page = vm_normal_page(vma, addr, ptent);
1033 if (!page)
1034 continue;
1035
1036 /* Clear accessed and referenced bits. */
1037 ptep_test_and_clear_young(vma, addr, pte);
1038 test_and_clear_page_young(page);
1039 ClearPageReferenced(page);
1040 }
1041 pte_unmap_unlock(pte - 1, ptl);
1042 cond_resched();
1043 return 0;
1044 }
1045
1046 static int clear_refs_test_walk(unsigned long start, unsigned long end,
1047 struct mm_walk *walk)
1048 {
1049 struct clear_refs_private *cp = walk->private;
1050 struct vm_area_struct *vma = walk->vma;
1051
1052 if (vma->vm_flags & VM_PFNMAP)
1053 return 1;
1054
1055 /*
1056 * Writing 1 to /proc/pid/clear_refs affects all pages.
1057 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages.
1058 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages.
1059 * Writing 4 to /proc/pid/clear_refs affects all pages.
1060 */
1061 if (cp->type == CLEAR_REFS_ANON && vma->vm_file)
1062 return 1;
1063 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file)
1064 return 1;
1065 return 0;
1066 }
1067
1068 static ssize_t clear_refs_write(struct file *file, const char __user *buf,
1069 size_t count, loff_t *ppos)
1070 {
1071 struct task_struct *task;
1072 char buffer[PROC_NUMBUF];
1073 struct mm_struct *mm;
1074 struct vm_area_struct *vma;
1075 enum clear_refs_types type;
1076 struct mmu_gather tlb;
1077 int itype;
1078 int rv;
1079
1080 memset(buffer, 0, sizeof(buffer));
1081 if (count > sizeof(buffer) - 1)
1082 count = sizeof(buffer) - 1;
1083 if (copy_from_user(buffer, buf, count))
1084 return -EFAULT;
1085 rv = kstrtoint(strstrip(buffer), 10, &itype);
1086 if (rv < 0)
1087 return rv;
1088 type = (enum clear_refs_types)itype;
1089 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
1090 return -EINVAL;
1091
1092 task = get_proc_task(file_inode(file));
1093 if (!task)
1094 return -ESRCH;
1095 mm = get_task_mm(task);
1096 if (mm) {
1097 struct clear_refs_private cp = {
1098 .type = type,
1099 };
1100 struct mm_walk clear_refs_walk = {
1101 .pmd_entry = clear_refs_pte_range,
1102 .test_walk = clear_refs_test_walk,
1103 .mm = mm,
1104 .private = &cp,
1105 };
1106
1107 if (type == CLEAR_REFS_MM_HIWATER_RSS) {
1108 if (down_write_killable(&mm->mmap_sem)) {
1109 count = -EINTR;
1110 goto out_mm;
1111 }
1112
1113 /*
1114 * Writing 5 to /proc/pid/clear_refs resets the peak
1115 * resident set size to this mm's current rss value.
1116 */
1117 reset_mm_hiwater_rss(mm);
1118 up_write(&mm->mmap_sem);
1119 goto out_mm;
1120 }
1121
1122 down_read(&mm->mmap_sem);
1123 tlb_gather_mmu(&tlb, mm, 0, -1);
1124 if (type == CLEAR_REFS_SOFT_DIRTY) {
1125 for (vma = mm->mmap; vma; vma = vma->vm_next) {
1126 if (!(vma->vm_flags & VM_SOFTDIRTY))
1127 continue;
1128 up_read(&mm->mmap_sem);
1129 if (down_write_killable(&mm->mmap_sem)) {
1130 count = -EINTR;
1131 goto out_mm;
1132 }
1133 for (vma = mm->mmap; vma; vma = vma->vm_next) {
1134 vma->vm_flags &= ~VM_SOFTDIRTY;
1135 vma_set_page_prot(vma);
1136 }
1137 downgrade_write(&mm->mmap_sem);
1138 break;
1139 }
1140 mmu_notifier_invalidate_range_start(mm, 0, -1);
1141 }
1142 walk_page_range(0, mm->highest_vm_end, &clear_refs_walk);
1143 if (type == CLEAR_REFS_SOFT_DIRTY)
1144 mmu_notifier_invalidate_range_end(mm, 0, -1);
1145 tlb_finish_mmu(&tlb, 0, -1);
1146 up_read(&mm->mmap_sem);
1147 out_mm:
1148 mmput(mm);
1149 }
1150 put_task_struct(task);
1151
1152 return count;
1153 }
1154
1155 const struct file_operations proc_clear_refs_operations = {
1156 .write = clear_refs_write,
1157 .llseek = noop_llseek,
1158 };
1159
1160 typedef struct {
1161 u64 pme;
1162 } pagemap_entry_t;
1163
1164 struct pagemapread {
1165 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */
1166 pagemap_entry_t *buffer;
1167 bool show_pfn;
1168 };
1169
1170 #define PAGEMAP_WALK_SIZE (PMD_SIZE)
1171 #define PAGEMAP_WALK_MASK (PMD_MASK)
1172
1173 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t)
1174 #define PM_PFRAME_BITS 55
1175 #define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0)
1176 #define PM_SOFT_DIRTY BIT_ULL(55)
1177 #define PM_MMAP_EXCLUSIVE BIT_ULL(56)
1178 #define PM_FILE BIT_ULL(61)
1179 #define PM_SWAP BIT_ULL(62)
1180 #define PM_PRESENT BIT_ULL(63)
1181
1182 #define PM_END_OF_BUFFER 1
1183
1184 static inline pagemap_entry_t make_pme(u64 frame, u64 flags)
1185 {
1186 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags };
1187 }
1188
1189 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme,
1190 struct pagemapread *pm)
1191 {
1192 pm->buffer[pm->pos++] = *pme;
1193 if (pm->pos >= pm->len)
1194 return PM_END_OF_BUFFER;
1195 return 0;
1196 }
1197
1198 static int pagemap_pte_hole(unsigned long start, unsigned long end,
1199 struct mm_walk *walk)
1200 {
1201 struct pagemapread *pm = walk->private;
1202 unsigned long addr = start;
1203 int err = 0;
1204
1205 while (addr < end) {
1206 struct vm_area_struct *vma = find_vma(walk->mm, addr);
1207 pagemap_entry_t pme = make_pme(0, 0);
1208 /* End of address space hole, which we mark as non-present. */
1209 unsigned long hole_end;
1210
1211 if (vma)
1212 hole_end = min(end, vma->vm_start);
1213 else
1214 hole_end = end;
1215
1216 for (; addr < hole_end; addr += PAGE_SIZE) {
1217 err = add_to_pagemap(addr, &pme, pm);
1218 if (err)
1219 goto out;
1220 }
1221
1222 if (!vma)
1223 break;
1224
1225 /* Addresses in the VMA. */
1226 if (vma->vm_flags & VM_SOFTDIRTY)
1227 pme = make_pme(0, PM_SOFT_DIRTY);
1228 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) {
1229 err = add_to_pagemap(addr, &pme, pm);
1230 if (err)
1231 goto out;
1232 }
1233 }
1234 out:
1235 return err;
1236 }
1237
1238 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm,
1239 struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1240 {
1241 u64 frame = 0, flags = 0;
1242 struct page *page = NULL;
1243
1244 if (pte_present(pte)) {
1245 if (pm->show_pfn)
1246 frame = pte_pfn(pte);
1247 flags |= PM_PRESENT;
1248 page = _vm_normal_page(vma, addr, pte, true);
1249 if (pte_soft_dirty(pte))
1250 flags |= PM_SOFT_DIRTY;
1251 } else if (is_swap_pte(pte)) {
1252 swp_entry_t entry;
1253 if (pte_swp_soft_dirty(pte))
1254 flags |= PM_SOFT_DIRTY;
1255 entry = pte_to_swp_entry(pte);
1256 if (pm->show_pfn)
1257 frame = swp_type(entry) |
1258 (swp_offset(entry) << MAX_SWAPFILES_SHIFT);
1259 flags |= PM_SWAP;
1260 if (is_migration_entry(entry))
1261 page = migration_entry_to_page(entry);
1262
1263 if (is_device_private_entry(entry))
1264 page = device_private_entry_to_page(entry);
1265 }
1266
1267 if (page && !PageAnon(page))
1268 flags |= PM_FILE;
1269 if (page && page_mapcount(page) == 1)
1270 flags |= PM_MMAP_EXCLUSIVE;
1271 if (vma->vm_flags & VM_SOFTDIRTY)
1272 flags |= PM_SOFT_DIRTY;
1273
1274 return make_pme(frame, flags);
1275 }
1276
1277 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
1278 struct mm_walk *walk)
1279 {
1280 struct vm_area_struct *vma = walk->vma;
1281 struct pagemapread *pm = walk->private;
1282 spinlock_t *ptl;
1283 pte_t *pte, *orig_pte;
1284 int err = 0;
1285
1286 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1287 ptl = pmd_trans_huge_lock(pmdp, vma);
1288 if (ptl) {
1289 u64 flags = 0, frame = 0;
1290 pmd_t pmd = *pmdp;
1291 struct page *page = NULL;
1292
1293 if (vma->vm_flags & VM_SOFTDIRTY)
1294 flags |= PM_SOFT_DIRTY;
1295
1296 if (pmd_present(pmd)) {
1297 page = pmd_page(pmd);
1298
1299 flags |= PM_PRESENT;
1300 if (pmd_soft_dirty(pmd))
1301 flags |= PM_SOFT_DIRTY;
1302 if (pm->show_pfn)
1303 frame = pmd_pfn(pmd) +
1304 ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1305 }
1306 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
1307 else if (is_swap_pmd(pmd)) {
1308 swp_entry_t entry = pmd_to_swp_entry(pmd);
1309 unsigned long offset;
1310
1311 if (pm->show_pfn) {
1312 offset = swp_offset(entry) +
1313 ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1314 frame = swp_type(entry) |
1315 (offset << MAX_SWAPFILES_SHIFT);
1316 }
1317 flags |= PM_SWAP;
1318 if (pmd_swp_soft_dirty(pmd))
1319 flags |= PM_SOFT_DIRTY;
1320 VM_BUG_ON(!is_pmd_migration_entry(pmd));
1321 page = migration_entry_to_page(entry);
1322 }
1323 #endif
1324
1325 if (page && page_mapcount(page) == 1)
1326 flags |= PM_MMAP_EXCLUSIVE;
1327
1328 for (; addr != end; addr += PAGE_SIZE) {
1329 pagemap_entry_t pme = make_pme(frame, flags);
1330
1331 err = add_to_pagemap(addr, &pme, pm);
1332 if (err)
1333 break;
1334 if (pm->show_pfn) {
1335 if (flags & PM_PRESENT)
1336 frame++;
1337 else if (flags & PM_SWAP)
1338 frame += (1 << MAX_SWAPFILES_SHIFT);
1339 }
1340 }
1341 spin_unlock(ptl);
1342 return err;
1343 }
1344
1345 if (pmd_trans_unstable(pmdp))
1346 return 0;
1347 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1348
1349 /*
1350 * We can assume that @vma always points to a valid one and @end never
1351 * goes beyond vma->vm_end.
1352 */
1353 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl);
1354 for (; addr < end; pte++, addr += PAGE_SIZE) {
1355 pagemap_entry_t pme;
1356
1357 pme = pte_to_pagemap_entry(pm, vma, addr, *pte);
1358 err = add_to_pagemap(addr, &pme, pm);
1359 if (err)
1360 break;
1361 }
1362 pte_unmap_unlock(orig_pte, ptl);
1363
1364 cond_resched();
1365
1366 return err;
1367 }
1368
1369 #ifdef CONFIG_HUGETLB_PAGE
1370 /* This function walks within one hugetlb entry in the single call */
1371 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask,
1372 unsigned long addr, unsigned long end,
1373 struct mm_walk *walk)
1374 {
1375 struct pagemapread *pm = walk->private;
1376 struct vm_area_struct *vma = walk->vma;
1377 u64 flags = 0, frame = 0;
1378 int err = 0;
1379 pte_t pte;
1380
1381 if (vma->vm_flags & VM_SOFTDIRTY)
1382 flags |= PM_SOFT_DIRTY;
1383
1384 pte = huge_ptep_get(ptep);
1385 if (pte_present(pte)) {
1386 struct page *page = pte_page(pte);
1387
1388 if (!PageAnon(page))
1389 flags |= PM_FILE;
1390
1391 if (page_mapcount(page) == 1)
1392 flags |= PM_MMAP_EXCLUSIVE;
1393
1394 flags |= PM_PRESENT;
1395 if (pm->show_pfn)
1396 frame = pte_pfn(pte) +
1397 ((addr & ~hmask) >> PAGE_SHIFT);
1398 }
1399
1400 for (; addr != end; addr += PAGE_SIZE) {
1401 pagemap_entry_t pme = make_pme(frame, flags);
1402
1403 err = add_to_pagemap(addr, &pme, pm);
1404 if (err)
1405 return err;
1406 if (pm->show_pfn && (flags & PM_PRESENT))
1407 frame++;
1408 }
1409
1410 cond_resched();
1411
1412 return err;
1413 }
1414 #endif /* HUGETLB_PAGE */
1415
1416 /*
1417 * /proc/pid/pagemap - an array mapping virtual pages to pfns
1418 *
1419 * For each page in the address space, this file contains one 64-bit entry
1420 * consisting of the following:
1421 *
1422 * Bits 0-54 page frame number (PFN) if present
1423 * Bits 0-4 swap type if swapped
1424 * Bits 5-54 swap offset if swapped
1425 * Bit 55 pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst)
1426 * Bit 56 page exclusively mapped
1427 * Bits 57-60 zero
1428 * Bit 61 page is file-page or shared-anon
1429 * Bit 62 page swapped
1430 * Bit 63 page present
1431 *
1432 * If the page is not present but in swap, then the PFN contains an
1433 * encoding of the swap file number and the page's offset into the
1434 * swap. Unmapped pages return a null PFN. This allows determining
1435 * precisely which pages are mapped (or in swap) and comparing mapped
1436 * pages between processes.
1437 *
1438 * Efficient users of this interface will use /proc/pid/maps to
1439 * determine which areas of memory are actually mapped and llseek to
1440 * skip over unmapped regions.
1441 */
1442 static ssize_t pagemap_read(struct file *file, char __user *buf,
1443 size_t count, loff_t *ppos)
1444 {
1445 struct mm_struct *mm = file->private_data;
1446 struct pagemapread pm;
1447 struct mm_walk pagemap_walk = {};
1448 unsigned long src;
1449 unsigned long svpfn;
1450 unsigned long start_vaddr;
1451 unsigned long end_vaddr;
1452 int ret = 0, copied = 0;
1453
1454 if (!mm || !mmget_not_zero(mm))
1455 goto out;
1456
1457 ret = -EINVAL;
1458 /* file position must be aligned */
1459 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
1460 goto out_mm;
1461
1462 ret = 0;
1463 if (!count)
1464 goto out_mm;
1465
1466 /* do not disclose physical addresses: attack vector */
1467 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN);
1468
1469 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
1470 pm.buffer = kmalloc_array(pm.len, PM_ENTRY_BYTES, GFP_KERNEL);
1471 ret = -ENOMEM;
1472 if (!pm.buffer)
1473 goto out_mm;
1474
1475 pagemap_walk.pmd_entry = pagemap_pmd_range;
1476 pagemap_walk.pte_hole = pagemap_pte_hole;
1477 #ifdef CONFIG_HUGETLB_PAGE
1478 pagemap_walk.hugetlb_entry = pagemap_hugetlb_range;
1479 #endif
1480 pagemap_walk.mm = mm;
1481 pagemap_walk.private = &pm;
1482
1483 src = *ppos;
1484 svpfn = src / PM_ENTRY_BYTES;
1485 start_vaddr = svpfn << PAGE_SHIFT;
1486 end_vaddr = mm->task_size;
1487
1488 /* watch out for wraparound */
1489 if (svpfn > mm->task_size >> PAGE_SHIFT)
1490 start_vaddr = end_vaddr;
1491
1492 /*
1493 * The odds are that this will stop walking way
1494 * before end_vaddr, because the length of the
1495 * user buffer is tracked in "pm", and the walk
1496 * will stop when we hit the end of the buffer.
1497 */
1498 ret = 0;
1499 while (count && (start_vaddr < end_vaddr)) {
1500 int len;
1501 unsigned long end;
1502
1503 pm.pos = 0;
1504 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
1505 /* overflow ? */
1506 if (end < start_vaddr || end > end_vaddr)
1507 end = end_vaddr;
1508 down_read(&mm->mmap_sem);
1509 ret = walk_page_range(start_vaddr, end, &pagemap_walk);
1510 up_read(&mm->mmap_sem);
1511 start_vaddr = end;
1512
1513 len = min(count, PM_ENTRY_BYTES * pm.pos);
1514 if (copy_to_user(buf, pm.buffer, len)) {
1515 ret = -EFAULT;
1516 goto out_free;
1517 }
1518 copied += len;
1519 buf += len;
1520 count -= len;
1521 }
1522 *ppos += copied;
1523 if (!ret || ret == PM_END_OF_BUFFER)
1524 ret = copied;
1525
1526 out_free:
1527 kfree(pm.buffer);
1528 out_mm:
1529 mmput(mm);
1530 out:
1531 return ret;
1532 }
1533
1534 static int pagemap_open(struct inode *inode, struct file *file)
1535 {
1536 struct mm_struct *mm;
1537
1538 mm = proc_mem_open(inode, PTRACE_MODE_READ);
1539 if (IS_ERR(mm))
1540 return PTR_ERR(mm);
1541 file->private_data = mm;
1542 return 0;
1543 }
1544
1545 static int pagemap_release(struct inode *inode, struct file *file)
1546 {
1547 struct mm_struct *mm = file->private_data;
1548
1549 if (mm)
1550 mmdrop(mm);
1551 return 0;
1552 }
1553
1554 const struct file_operations proc_pagemap_operations = {
1555 .llseek = mem_lseek, /* borrow this */
1556 .read = pagemap_read,
1557 .open = pagemap_open,
1558 .release = pagemap_release,
1559 };
1560 #endif /* CONFIG_PROC_PAGE_MONITOR */
1561
1562 #ifdef CONFIG_NUMA
1563
1564 struct numa_maps {
1565 unsigned long pages;
1566 unsigned long anon;
1567 unsigned long active;
1568 unsigned long writeback;
1569 unsigned long mapcount_max;
1570 unsigned long dirty;
1571 unsigned long swapcache;
1572 unsigned long node[MAX_NUMNODES];
1573 };
1574
1575 struct numa_maps_private {
1576 struct proc_maps_private proc_maps;
1577 struct numa_maps md;
1578 };
1579
1580 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
1581 unsigned long nr_pages)
1582 {
1583 int count = page_mapcount(page);
1584
1585 md->pages += nr_pages;
1586 if (pte_dirty || PageDirty(page))
1587 md->dirty += nr_pages;
1588
1589 if (PageSwapCache(page))
1590 md->swapcache += nr_pages;
1591
1592 if (PageActive(page) || PageUnevictable(page))
1593 md->active += nr_pages;
1594
1595 if (PageWriteback(page))
1596 md->writeback += nr_pages;
1597
1598 if (PageAnon(page))
1599 md->anon += nr_pages;
1600
1601 if (count > md->mapcount_max)
1602 md->mapcount_max = count;
1603
1604 md->node[page_to_nid(page)] += nr_pages;
1605 }
1606
1607 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
1608 unsigned long addr)
1609 {
1610 struct page *page;
1611 int nid;
1612
1613 if (!pte_present(pte))
1614 return NULL;
1615
1616 page = vm_normal_page(vma, addr, pte);
1617 if (!page)
1618 return NULL;
1619
1620 if (PageReserved(page))
1621 return NULL;
1622
1623 nid = page_to_nid(page);
1624 if (!node_isset(nid, node_states[N_MEMORY]))
1625 return NULL;
1626
1627 return page;
1628 }
1629
1630 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1631 static struct page *can_gather_numa_stats_pmd(pmd_t pmd,
1632 struct vm_area_struct *vma,
1633 unsigned long addr)
1634 {
1635 struct page *page;
1636 int nid;
1637
1638 if (!pmd_present(pmd))
1639 return NULL;
1640
1641 page = vm_normal_page_pmd(vma, addr, pmd);
1642 if (!page)
1643 return NULL;
1644
1645 if (PageReserved(page))
1646 return NULL;
1647
1648 nid = page_to_nid(page);
1649 if (!node_isset(nid, node_states[N_MEMORY]))
1650 return NULL;
1651
1652 return page;
1653 }
1654 #endif
1655
1656 static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
1657 unsigned long end, struct mm_walk *walk)
1658 {
1659 struct numa_maps *md = walk->private;
1660 struct vm_area_struct *vma = walk->vma;
1661 spinlock_t *ptl;
1662 pte_t *orig_pte;
1663 pte_t *pte;
1664
1665 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1666 ptl = pmd_trans_huge_lock(pmd, vma);
1667 if (ptl) {
1668 struct page *page;
1669
1670 page = can_gather_numa_stats_pmd(*pmd, vma, addr);
1671 if (page)
1672 gather_stats(page, md, pmd_dirty(*pmd),
1673 HPAGE_PMD_SIZE/PAGE_SIZE);
1674 spin_unlock(ptl);
1675 return 0;
1676 }
1677
1678 if (pmd_trans_unstable(pmd))
1679 return 0;
1680 #endif
1681 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
1682 do {
1683 struct page *page = can_gather_numa_stats(*pte, vma, addr);
1684 if (!page)
1685 continue;
1686 gather_stats(page, md, pte_dirty(*pte), 1);
1687
1688 } while (pte++, addr += PAGE_SIZE, addr != end);
1689 pte_unmap_unlock(orig_pte, ptl);
1690 cond_resched();
1691 return 0;
1692 }
1693 #ifdef CONFIG_HUGETLB_PAGE
1694 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1695 unsigned long addr, unsigned long end, struct mm_walk *walk)
1696 {
1697 pte_t huge_pte = huge_ptep_get(pte);
1698 struct numa_maps *md;
1699 struct page *page;
1700
1701 if (!pte_present(huge_pte))
1702 return 0;
1703
1704 page = pte_page(huge_pte);
1705 if (!page)
1706 return 0;
1707
1708 md = walk->private;
1709 gather_stats(page, md, pte_dirty(huge_pte), 1);
1710 return 0;
1711 }
1712
1713 #else
1714 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1715 unsigned long addr, unsigned long end, struct mm_walk *walk)
1716 {
1717 return 0;
1718 }
1719 #endif
1720
1721 /*
1722 * Display pages allocated per node and memory policy via /proc.
1723 */
1724 static int show_numa_map(struct seq_file *m, void *v)
1725 {
1726 struct numa_maps_private *numa_priv = m->private;
1727 struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
1728 struct vm_area_struct *vma = v;
1729 struct numa_maps *md = &numa_priv->md;
1730 struct file *file = vma->vm_file;
1731 struct mm_struct *mm = vma->vm_mm;
1732 struct mm_walk walk = {
1733 .hugetlb_entry = gather_hugetlb_stats,
1734 .pmd_entry = gather_pte_stats,
1735 .private = md,
1736 .mm = mm,
1737 };
1738 struct mempolicy *pol;
1739 char buffer[64];
1740 int nid;
1741
1742 if (!mm)
1743 return 0;
1744
1745 /* Ensure we start with an empty set of numa_maps statistics. */
1746 memset(md, 0, sizeof(*md));
1747
1748 pol = __get_vma_policy(vma, vma->vm_start);
1749 if (pol) {
1750 mpol_to_str(buffer, sizeof(buffer), pol);
1751 mpol_cond_put(pol);
1752 } else {
1753 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy);
1754 }
1755
1756 seq_printf(m, "%08lx %s", vma->vm_start, buffer);
1757
1758 if (file) {
1759 seq_puts(m, " file=");
1760 seq_file_path(m, file, "\n\t= ");
1761 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1762 seq_puts(m, " heap");
1763 } else if (is_stack(vma)) {
1764 seq_puts(m, " stack");
1765 }
1766
1767 if (is_vm_hugetlb_page(vma))
1768 seq_puts(m, " huge");
1769
1770 /* mmap_sem is held by m_start */
1771 walk_page_vma(vma, &walk);
1772
1773 if (!md->pages)
1774 goto out;
1775
1776 if (md->anon)
1777 seq_printf(m, " anon=%lu", md->anon);
1778
1779 if (md->dirty)
1780 seq_printf(m, " dirty=%lu", md->dirty);
1781
1782 if (md->pages != md->anon && md->pages != md->dirty)
1783 seq_printf(m, " mapped=%lu", md->pages);
1784
1785 if (md->mapcount_max > 1)
1786 seq_printf(m, " mapmax=%lu", md->mapcount_max);
1787
1788 if (md->swapcache)
1789 seq_printf(m, " swapcache=%lu", md->swapcache);
1790
1791 if (md->active < md->pages && !is_vm_hugetlb_page(vma))
1792 seq_printf(m, " active=%lu", md->active);
1793
1794 if (md->writeback)
1795 seq_printf(m, " writeback=%lu", md->writeback);
1796
1797 for_each_node_state(nid, N_MEMORY)
1798 if (md->node[nid])
1799 seq_printf(m, " N%d=%lu", nid, md->node[nid]);
1800
1801 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10);
1802 out:
1803 seq_putc(m, '\n');
1804 m_cache_vma(m, vma);
1805 return 0;
1806 }
1807
1808 static const struct seq_operations proc_pid_numa_maps_op = {
1809 .start = m_start,
1810 .next = m_next,
1811 .stop = m_stop,
1812 .show = show_numa_map,
1813 };
1814
1815 static int pid_numa_maps_open(struct inode *inode, struct file *file)
1816 {
1817 return proc_maps_open(inode, file, &proc_pid_numa_maps_op,
1818 sizeof(struct numa_maps_private));
1819 }
1820
1821 const struct file_operations proc_pid_numa_maps_operations = {
1822 .open = pid_numa_maps_open,
1823 .read = seq_read,
1824 .llseek = seq_lseek,
1825 .release = proc_map_release,
1826 };
1827
1828 #endif /* CONFIG_NUMA */
Linux with added FPC-III support