Loading...
1#include <linux/mm.h>
2#include <linux/hugetlb.h>
3#include <linux/huge_mm.h>
4#include <linux/mount.h>
5#include <linux/seq_file.h>
6#include <linux/highmem.h>
7#include <linux/ptrace.h>
8#include <linux/slab.h>
9#include <linux/pagemap.h>
10#include <linux/mempolicy.h>
11#include <linux/rmap.h>
12#include <linux/swap.h>
13#include <linux/swapops.h>
14
15#include <asm/elf.h>
16#include <asm/uaccess.h>
17#include <asm/tlbflush.h>
18#include "internal.h"
19
20void task_mem(struct seq_file *m, struct mm_struct *mm)
21{
22 unsigned long data, text, lib, swap;
23 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
24
25 /*
26 * Note: to minimize their overhead, mm maintains hiwater_vm and
27 * hiwater_rss only when about to *lower* total_vm or rss. Any
28 * collector of these hiwater stats must therefore get total_vm
29 * and rss too, which will usually be the higher. Barriers? not
30 * worth the effort, such snapshots can always be inconsistent.
31 */
32 hiwater_vm = total_vm = mm->total_vm;
33 if (hiwater_vm < mm->hiwater_vm)
34 hiwater_vm = mm->hiwater_vm;
35 hiwater_rss = total_rss = get_mm_rss(mm);
36 if (hiwater_rss < mm->hiwater_rss)
37 hiwater_rss = mm->hiwater_rss;
38
39 data = mm->total_vm - mm->shared_vm - mm->stack_vm;
40 text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10;
41 lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text;
42 swap = get_mm_counter(mm, MM_SWAPENTS);
43 seq_printf(m,
44 "VmPeak:\t%8lu kB\n"
45 "VmSize:\t%8lu kB\n"
46 "VmLck:\t%8lu kB\n"
47 "VmPin:\t%8lu kB\n"
48 "VmHWM:\t%8lu kB\n"
49 "VmRSS:\t%8lu kB\n"
50 "VmData:\t%8lu kB\n"
51 "VmStk:\t%8lu kB\n"
52 "VmExe:\t%8lu kB\n"
53 "VmLib:\t%8lu kB\n"
54 "VmPTE:\t%8lu kB\n"
55 "VmSwap:\t%8lu kB\n",
56 hiwater_vm << (PAGE_SHIFT-10),
57 (total_vm - mm->reserved_vm) << (PAGE_SHIFT-10),
58 mm->locked_vm << (PAGE_SHIFT-10),
59 mm->pinned_vm << (PAGE_SHIFT-10),
60 hiwater_rss << (PAGE_SHIFT-10),
61 total_rss << (PAGE_SHIFT-10),
62 data << (PAGE_SHIFT-10),
63 mm->stack_vm << (PAGE_SHIFT-10), text, lib,
64 (PTRS_PER_PTE*sizeof(pte_t)*mm->nr_ptes) >> 10,
65 swap << (PAGE_SHIFT-10));
66}
67
68unsigned long task_vsize(struct mm_struct *mm)
69{
70 return PAGE_SIZE * mm->total_vm;
71}
72
73unsigned long task_statm(struct mm_struct *mm,
74 unsigned long *shared, unsigned long *text,
75 unsigned long *data, unsigned long *resident)
76{
77 *shared = get_mm_counter(mm, MM_FILEPAGES);
78 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
79 >> PAGE_SHIFT;
80 *data = mm->total_vm - mm->shared_vm;
81 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
82 return mm->total_vm;
83}
84
85static void pad_len_spaces(struct seq_file *m, int len)
86{
87 len = 25 + sizeof(void*) * 6 - len;
88 if (len < 1)
89 len = 1;
90 seq_printf(m, "%*c", len, ' ');
91}
92
93static void vma_stop(struct proc_maps_private *priv, struct vm_area_struct *vma)
94{
95 if (vma && vma != priv->tail_vma) {
96 struct mm_struct *mm = vma->vm_mm;
97 up_read(&mm->mmap_sem);
98 mmput(mm);
99 }
100}
101
102static void *m_start(struct seq_file *m, loff_t *pos)
103{
104 struct proc_maps_private *priv = m->private;
105 unsigned long last_addr = m->version;
106 struct mm_struct *mm;
107 struct vm_area_struct *vma, *tail_vma = NULL;
108 loff_t l = *pos;
109
110 /* Clear the per syscall fields in priv */
111 priv->task = NULL;
112 priv->tail_vma = NULL;
113
114 /*
115 * We remember last_addr rather than next_addr to hit with
116 * mmap_cache most of the time. We have zero last_addr at
117 * the beginning and also after lseek. We will have -1 last_addr
118 * after the end of the vmas.
119 */
120
121 if (last_addr == -1UL)
122 return NULL;
123
124 priv->task = get_pid_task(priv->pid, PIDTYPE_PID);
125 if (!priv->task)
126 return ERR_PTR(-ESRCH);
127
128 mm = mm_access(priv->task, PTRACE_MODE_READ);
129 if (!mm || IS_ERR(mm))
130 return mm;
131 down_read(&mm->mmap_sem);
132
133 tail_vma = get_gate_vma(priv->task->mm);
134 priv->tail_vma = tail_vma;
135
136 /* Start with last addr hint */
137 vma = find_vma(mm, last_addr);
138 if (last_addr && vma) {
139 vma = vma->vm_next;
140 goto out;
141 }
142
143 /*
144 * Check the vma index is within the range and do
145 * sequential scan until m_index.
146 */
147 vma = NULL;
148 if ((unsigned long)l < mm->map_count) {
149 vma = mm->mmap;
150 while (l-- && vma)
151 vma = vma->vm_next;
152 goto out;
153 }
154
155 if (l != mm->map_count)
156 tail_vma = NULL; /* After gate vma */
157
158out:
159 if (vma)
160 return vma;
161
162 /* End of vmas has been reached */
163 m->version = (tail_vma != NULL)? 0: -1UL;
164 up_read(&mm->mmap_sem);
165 mmput(mm);
166 return tail_vma;
167}
168
169static void *m_next(struct seq_file *m, void *v, loff_t *pos)
170{
171 struct proc_maps_private *priv = m->private;
172 struct vm_area_struct *vma = v;
173 struct vm_area_struct *tail_vma = priv->tail_vma;
174
175 (*pos)++;
176 if (vma && (vma != tail_vma) && vma->vm_next)
177 return vma->vm_next;
178 vma_stop(priv, vma);
179 return (vma != tail_vma)? tail_vma: NULL;
180}
181
182static void m_stop(struct seq_file *m, void *v)
183{
184 struct proc_maps_private *priv = m->private;
185 struct vm_area_struct *vma = v;
186
187 if (!IS_ERR(vma))
188 vma_stop(priv, vma);
189 if (priv->task)
190 put_task_struct(priv->task);
191}
192
193static int do_maps_open(struct inode *inode, struct file *file,
194 const struct seq_operations *ops)
195{
196 struct proc_maps_private *priv;
197 int ret = -ENOMEM;
198 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
199 if (priv) {
200 priv->pid = proc_pid(inode);
201 ret = seq_open(file, ops);
202 if (!ret) {
203 struct seq_file *m = file->private_data;
204 m->private = priv;
205 } else {
206 kfree(priv);
207 }
208 }
209 return ret;
210}
211
212static void
213show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid)
214{
215 struct mm_struct *mm = vma->vm_mm;
216 struct file *file = vma->vm_file;
217 struct proc_maps_private *priv = m->private;
218 struct task_struct *task = priv->task;
219 vm_flags_t flags = vma->vm_flags;
220 unsigned long ino = 0;
221 unsigned long long pgoff = 0;
222 unsigned long start, end;
223 dev_t dev = 0;
224 int len;
225 const char *name = NULL;
226
227 if (file) {
228 struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
229 dev = inode->i_sb->s_dev;
230 ino = inode->i_ino;
231 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
232 }
233
234 /* We don't show the stack guard page in /proc/maps */
235 start = vma->vm_start;
236 if (stack_guard_page_start(vma, start))
237 start += PAGE_SIZE;
238 end = vma->vm_end;
239 if (stack_guard_page_end(vma, end))
240 end -= PAGE_SIZE;
241
242 seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu %n",
243 start,
244 end,
245 flags & VM_READ ? 'r' : '-',
246 flags & VM_WRITE ? 'w' : '-',
247 flags & VM_EXEC ? 'x' : '-',
248 flags & VM_MAYSHARE ? 's' : 'p',
249 pgoff,
250 MAJOR(dev), MINOR(dev), ino, &len);
251
252 /*
253 * Print the dentry name for named mappings, and a
254 * special [heap] marker for the heap:
255 */
256 if (file) {
257 pad_len_spaces(m, len);
258 seq_path(m, &file->f_path, "\n");
259 goto done;
260 }
261
262 name = arch_vma_name(vma);
263 if (!name) {
264 pid_t tid;
265
266 if (!mm) {
267 name = "[vdso]";
268 goto done;
269 }
270
271 if (vma->vm_start <= mm->brk &&
272 vma->vm_end >= mm->start_brk) {
273 name = "[heap]";
274 goto done;
275 }
276
277 tid = vm_is_stack(task, vma, is_pid);
278
279 if (tid != 0) {
280 /*
281 * Thread stack in /proc/PID/task/TID/maps or
282 * the main process stack.
283 */
284 if (!is_pid || (vma->vm_start <= mm->start_stack &&
285 vma->vm_end >= mm->start_stack)) {
286 name = "[stack]";
287 } else {
288 /* Thread stack in /proc/PID/maps */
289 pad_len_spaces(m, len);
290 seq_printf(m, "[stack:%d]", tid);
291 }
292 }
293 }
294
295done:
296 if (name) {
297 pad_len_spaces(m, len);
298 seq_puts(m, name);
299 }
300 seq_putc(m, '\n');
301}
302
303static int show_map(struct seq_file *m, void *v, int is_pid)
304{
305 struct vm_area_struct *vma = v;
306 struct proc_maps_private *priv = m->private;
307 struct task_struct *task = priv->task;
308
309 show_map_vma(m, vma, is_pid);
310
311 if (m->count < m->size) /* vma is copied successfully */
312 m->version = (vma != get_gate_vma(task->mm))
313 ? vma->vm_start : 0;
314 return 0;
315}
316
317static int show_pid_map(struct seq_file *m, void *v)
318{
319 return show_map(m, v, 1);
320}
321
322static int show_tid_map(struct seq_file *m, void *v)
323{
324 return show_map(m, v, 0);
325}
326
327static const struct seq_operations proc_pid_maps_op = {
328 .start = m_start,
329 .next = m_next,
330 .stop = m_stop,
331 .show = show_pid_map
332};
333
334static const struct seq_operations proc_tid_maps_op = {
335 .start = m_start,
336 .next = m_next,
337 .stop = m_stop,
338 .show = show_tid_map
339};
340
341static int pid_maps_open(struct inode *inode, struct file *file)
342{
343 return do_maps_open(inode, file, &proc_pid_maps_op);
344}
345
346static int tid_maps_open(struct inode *inode, struct file *file)
347{
348 return do_maps_open(inode, file, &proc_tid_maps_op);
349}
350
351const struct file_operations proc_pid_maps_operations = {
352 .open = pid_maps_open,
353 .read = seq_read,
354 .llseek = seq_lseek,
355 .release = seq_release_private,
356};
357
358const struct file_operations proc_tid_maps_operations = {
359 .open = tid_maps_open,
360 .read = seq_read,
361 .llseek = seq_lseek,
362 .release = seq_release_private,
363};
364
365/*
366 * Proportional Set Size(PSS): my share of RSS.
367 *
368 * PSS of a process is the count of pages it has in memory, where each
369 * page is divided by the number of processes sharing it. So if a
370 * process has 1000 pages all to itself, and 1000 shared with one other
371 * process, its PSS will be 1500.
372 *
373 * To keep (accumulated) division errors low, we adopt a 64bit
374 * fixed-point pss counter to minimize division errors. So (pss >>
375 * PSS_SHIFT) would be the real byte count.
376 *
377 * A shift of 12 before division means (assuming 4K page size):
378 * - 1M 3-user-pages add up to 8KB errors;
379 * - supports mapcount up to 2^24, or 16M;
380 * - supports PSS up to 2^52 bytes, or 4PB.
381 */
382#define PSS_SHIFT 12
383
384#ifdef CONFIG_PROC_PAGE_MONITOR
385struct mem_size_stats {
386 struct vm_area_struct *vma;
387 unsigned long resident;
388 unsigned long shared_clean;
389 unsigned long shared_dirty;
390 unsigned long private_clean;
391 unsigned long private_dirty;
392 unsigned long referenced;
393 unsigned long anonymous;
394 unsigned long anonymous_thp;
395 unsigned long swap;
396 unsigned long nonlinear;
397 u64 pss;
398};
399
400
401static void smaps_pte_entry(pte_t ptent, unsigned long addr,
402 unsigned long ptent_size, struct mm_walk *walk)
403{
404 struct mem_size_stats *mss = walk->private;
405 struct vm_area_struct *vma = mss->vma;
406 pgoff_t pgoff = linear_page_index(vma, addr);
407 struct page *page = NULL;
408 int mapcount;
409
410 if (pte_present(ptent)) {
411 page = vm_normal_page(vma, addr, ptent);
412 } else if (is_swap_pte(ptent)) {
413 swp_entry_t swpent = pte_to_swp_entry(ptent);
414
415 if (!non_swap_entry(swpent))
416 mss->swap += ptent_size;
417 else if (is_migration_entry(swpent))
418 page = migration_entry_to_page(swpent);
419 } else if (pte_file(ptent)) {
420 if (pte_to_pgoff(ptent) != pgoff)
421 mss->nonlinear += ptent_size;
422 }
423
424 if (!page)
425 return;
426
427 if (PageAnon(page))
428 mss->anonymous += ptent_size;
429
430 if (page->index != pgoff)
431 mss->nonlinear += ptent_size;
432
433 mss->resident += ptent_size;
434 /* Accumulate the size in pages that have been accessed. */
435 if (pte_young(ptent) || PageReferenced(page))
436 mss->referenced += ptent_size;
437 mapcount = page_mapcount(page);
438 if (mapcount >= 2) {
439 if (pte_dirty(ptent) || PageDirty(page))
440 mss->shared_dirty += ptent_size;
441 else
442 mss->shared_clean += ptent_size;
443 mss->pss += (ptent_size << PSS_SHIFT) / mapcount;
444 } else {
445 if (pte_dirty(ptent) || PageDirty(page))
446 mss->private_dirty += ptent_size;
447 else
448 mss->private_clean += ptent_size;
449 mss->pss += (ptent_size << PSS_SHIFT);
450 }
451}
452
453static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
454 struct mm_walk *walk)
455{
456 struct mem_size_stats *mss = walk->private;
457 struct vm_area_struct *vma = mss->vma;
458 pte_t *pte;
459 spinlock_t *ptl;
460
461 if (pmd_trans_huge_lock(pmd, vma) == 1) {
462 smaps_pte_entry(*(pte_t *)pmd, addr, HPAGE_PMD_SIZE, walk);
463 spin_unlock(&walk->mm->page_table_lock);
464 mss->anonymous_thp += HPAGE_PMD_SIZE;
465 return 0;
466 }
467
468 if (pmd_trans_unstable(pmd))
469 return 0;
470 /*
471 * The mmap_sem held all the way back in m_start() is what
472 * keeps khugepaged out of here and from collapsing things
473 * in here.
474 */
475 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
476 for (; addr != end; pte++, addr += PAGE_SIZE)
477 smaps_pte_entry(*pte, addr, PAGE_SIZE, walk);
478 pte_unmap_unlock(pte - 1, ptl);
479 cond_resched();
480 return 0;
481}
482
483static int show_smap(struct seq_file *m, void *v, int is_pid)
484{
485 struct proc_maps_private *priv = m->private;
486 struct task_struct *task = priv->task;
487 struct vm_area_struct *vma = v;
488 struct mem_size_stats mss;
489 struct mm_walk smaps_walk = {
490 .pmd_entry = smaps_pte_range,
491 .mm = vma->vm_mm,
492 .private = &mss,
493 };
494
495 memset(&mss, 0, sizeof mss);
496 mss.vma = vma;
497 /* mmap_sem is held in m_start */
498 if (vma->vm_mm && !is_vm_hugetlb_page(vma))
499 walk_page_range(vma->vm_start, vma->vm_end, &smaps_walk);
500
501 show_map_vma(m, vma, is_pid);
502
503 seq_printf(m,
504 "Size: %8lu kB\n"
505 "Rss: %8lu kB\n"
506 "Pss: %8lu kB\n"
507 "Shared_Clean: %8lu kB\n"
508 "Shared_Dirty: %8lu kB\n"
509 "Private_Clean: %8lu kB\n"
510 "Private_Dirty: %8lu kB\n"
511 "Referenced: %8lu kB\n"
512 "Anonymous: %8lu kB\n"
513 "AnonHugePages: %8lu kB\n"
514 "Swap: %8lu kB\n"
515 "KernelPageSize: %8lu kB\n"
516 "MMUPageSize: %8lu kB\n"
517 "Locked: %8lu kB\n",
518 (vma->vm_end - vma->vm_start) >> 10,
519 mss.resident >> 10,
520 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)),
521 mss.shared_clean >> 10,
522 mss.shared_dirty >> 10,
523 mss.private_clean >> 10,
524 mss.private_dirty >> 10,
525 mss.referenced >> 10,
526 mss.anonymous >> 10,
527 mss.anonymous_thp >> 10,
528 mss.swap >> 10,
529 vma_kernel_pagesize(vma) >> 10,
530 vma_mmu_pagesize(vma) >> 10,
531 (vma->vm_flags & VM_LOCKED) ?
532 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0);
533
534 if (vma->vm_flags & VM_NONLINEAR)
535 seq_printf(m, "Nonlinear: %8lu kB\n",
536 mss.nonlinear >> 10);
537
538 if (m->count < m->size) /* vma is copied successfully */
539 m->version = (vma != get_gate_vma(task->mm))
540 ? vma->vm_start : 0;
541 return 0;
542}
543
544static int show_pid_smap(struct seq_file *m, void *v)
545{
546 return show_smap(m, v, 1);
547}
548
549static int show_tid_smap(struct seq_file *m, void *v)
550{
551 return show_smap(m, v, 0);
552}
553
554static const struct seq_operations proc_pid_smaps_op = {
555 .start = m_start,
556 .next = m_next,
557 .stop = m_stop,
558 .show = show_pid_smap
559};
560
561static const struct seq_operations proc_tid_smaps_op = {
562 .start = m_start,
563 .next = m_next,
564 .stop = m_stop,
565 .show = show_tid_smap
566};
567
568static int pid_smaps_open(struct inode *inode, struct file *file)
569{
570 return do_maps_open(inode, file, &proc_pid_smaps_op);
571}
572
573static int tid_smaps_open(struct inode *inode, struct file *file)
574{
575 return do_maps_open(inode, file, &proc_tid_smaps_op);
576}
577
578const struct file_operations proc_pid_smaps_operations = {
579 .open = pid_smaps_open,
580 .read = seq_read,
581 .llseek = seq_lseek,
582 .release = seq_release_private,
583};
584
585const struct file_operations proc_tid_smaps_operations = {
586 .open = tid_smaps_open,
587 .read = seq_read,
588 .llseek = seq_lseek,
589 .release = seq_release_private,
590};
591
592static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
593 unsigned long end, struct mm_walk *walk)
594{
595 struct vm_area_struct *vma = walk->private;
596 pte_t *pte, ptent;
597 spinlock_t *ptl;
598 struct page *page;
599
600 split_huge_page_pmd(walk->mm, pmd);
601 if (pmd_trans_unstable(pmd))
602 return 0;
603
604 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
605 for (; addr != end; pte++, addr += PAGE_SIZE) {
606 ptent = *pte;
607 if (!pte_present(ptent))
608 continue;
609
610 page = vm_normal_page(vma, addr, ptent);
611 if (!page)
612 continue;
613
614 /* Clear accessed and referenced bits. */
615 ptep_test_and_clear_young(vma, addr, pte);
616 ClearPageReferenced(page);
617 }
618 pte_unmap_unlock(pte - 1, ptl);
619 cond_resched();
620 return 0;
621}
622
623#define CLEAR_REFS_ALL 1
624#define CLEAR_REFS_ANON 2
625#define CLEAR_REFS_MAPPED 3
626
627static ssize_t clear_refs_write(struct file *file, const char __user *buf,
628 size_t count, loff_t *ppos)
629{
630 struct task_struct *task;
631 char buffer[PROC_NUMBUF];
632 struct mm_struct *mm;
633 struct vm_area_struct *vma;
634 int type;
635 int rv;
636
637 memset(buffer, 0, sizeof(buffer));
638 if (count > sizeof(buffer) - 1)
639 count = sizeof(buffer) - 1;
640 if (copy_from_user(buffer, buf, count))
641 return -EFAULT;
642 rv = kstrtoint(strstrip(buffer), 10, &type);
643 if (rv < 0)
644 return rv;
645 if (type < CLEAR_REFS_ALL || type > CLEAR_REFS_MAPPED)
646 return -EINVAL;
647 task = get_proc_task(file->f_path.dentry->d_inode);
648 if (!task)
649 return -ESRCH;
650 mm = get_task_mm(task);
651 if (mm) {
652 struct mm_walk clear_refs_walk = {
653 .pmd_entry = clear_refs_pte_range,
654 .mm = mm,
655 };
656 down_read(&mm->mmap_sem);
657 for (vma = mm->mmap; vma; vma = vma->vm_next) {
658 clear_refs_walk.private = vma;
659 if (is_vm_hugetlb_page(vma))
660 continue;
661 /*
662 * Writing 1 to /proc/pid/clear_refs affects all pages.
663 *
664 * Writing 2 to /proc/pid/clear_refs only affects
665 * Anonymous pages.
666 *
667 * Writing 3 to /proc/pid/clear_refs only affects file
668 * mapped pages.
669 */
670 if (type == CLEAR_REFS_ANON && vma->vm_file)
671 continue;
672 if (type == CLEAR_REFS_MAPPED && !vma->vm_file)
673 continue;
674 walk_page_range(vma->vm_start, vma->vm_end,
675 &clear_refs_walk);
676 }
677 flush_tlb_mm(mm);
678 up_read(&mm->mmap_sem);
679 mmput(mm);
680 }
681 put_task_struct(task);
682
683 return count;
684}
685
686const struct file_operations proc_clear_refs_operations = {
687 .write = clear_refs_write,
688 .llseek = noop_llseek,
689};
690
691typedef struct {
692 u64 pme;
693} pagemap_entry_t;
694
695struct pagemapread {
696 int pos, len;
697 pagemap_entry_t *buffer;
698};
699
700#define PAGEMAP_WALK_SIZE (PMD_SIZE)
701#define PAGEMAP_WALK_MASK (PMD_MASK)
702
703#define PM_ENTRY_BYTES sizeof(u64)
704#define PM_STATUS_BITS 3
705#define PM_STATUS_OFFSET (64 - PM_STATUS_BITS)
706#define PM_STATUS_MASK (((1LL << PM_STATUS_BITS) - 1) << PM_STATUS_OFFSET)
707#define PM_STATUS(nr) (((nr) << PM_STATUS_OFFSET) & PM_STATUS_MASK)
708#define PM_PSHIFT_BITS 6
709#define PM_PSHIFT_OFFSET (PM_STATUS_OFFSET - PM_PSHIFT_BITS)
710#define PM_PSHIFT_MASK (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET)
711#define PM_PSHIFT(x) (((u64) (x) << PM_PSHIFT_OFFSET) & PM_PSHIFT_MASK)
712#define PM_PFRAME_MASK ((1LL << PM_PSHIFT_OFFSET) - 1)
713#define PM_PFRAME(x) ((x) & PM_PFRAME_MASK)
714
715#define PM_PRESENT PM_STATUS(4LL)
716#define PM_SWAP PM_STATUS(2LL)
717#define PM_FILE PM_STATUS(1LL)
718#define PM_NOT_PRESENT PM_PSHIFT(PAGE_SHIFT)
719#define PM_END_OF_BUFFER 1
720
721static inline pagemap_entry_t make_pme(u64 val)
722{
723 return (pagemap_entry_t) { .pme = val };
724}
725
726static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme,
727 struct pagemapread *pm)
728{
729 pm->buffer[pm->pos++] = *pme;
730 if (pm->pos >= pm->len)
731 return PM_END_OF_BUFFER;
732 return 0;
733}
734
735static int pagemap_pte_hole(unsigned long start, unsigned long end,
736 struct mm_walk *walk)
737{
738 struct pagemapread *pm = walk->private;
739 unsigned long addr;
740 int err = 0;
741 pagemap_entry_t pme = make_pme(PM_NOT_PRESENT);
742
743 for (addr = start; addr < end; addr += PAGE_SIZE) {
744 err = add_to_pagemap(addr, &pme, pm);
745 if (err)
746 break;
747 }
748 return err;
749}
750
751static void pte_to_pagemap_entry(pagemap_entry_t *pme,
752 struct vm_area_struct *vma, unsigned long addr, pte_t pte)
753{
754 u64 frame, flags;
755 struct page *page = NULL;
756
757 if (pte_present(pte)) {
758 frame = pte_pfn(pte);
759 flags = PM_PRESENT;
760 page = vm_normal_page(vma, addr, pte);
761 } else if (is_swap_pte(pte)) {
762 swp_entry_t entry = pte_to_swp_entry(pte);
763
764 frame = swp_type(entry) |
765 (swp_offset(entry) << MAX_SWAPFILES_SHIFT);
766 flags = PM_SWAP;
767 if (is_migration_entry(entry))
768 page = migration_entry_to_page(entry);
769 } else {
770 *pme = make_pme(PM_NOT_PRESENT);
771 return;
772 }
773
774 if (page && !PageAnon(page))
775 flags |= PM_FILE;
776
777 *pme = make_pme(PM_PFRAME(frame) | PM_PSHIFT(PAGE_SHIFT) | flags);
778}
779
780#ifdef CONFIG_TRANSPARENT_HUGEPAGE
781static void thp_pmd_to_pagemap_entry(pagemap_entry_t *pme,
782 pmd_t pmd, int offset)
783{
784 /*
785 * Currently pmd for thp is always present because thp can not be
786 * swapped-out, migrated, or HWPOISONed (split in such cases instead.)
787 * This if-check is just to prepare for future implementation.
788 */
789 if (pmd_present(pmd))
790 *pme = make_pme(PM_PFRAME(pmd_pfn(pmd) + offset)
791 | PM_PSHIFT(PAGE_SHIFT) | PM_PRESENT);
792 else
793 *pme = make_pme(PM_NOT_PRESENT);
794}
795#else
796static inline void thp_pmd_to_pagemap_entry(pagemap_entry_t *pme,
797 pmd_t pmd, int offset)
798{
799}
800#endif
801
802static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
803 struct mm_walk *walk)
804{
805 struct vm_area_struct *vma;
806 struct pagemapread *pm = walk->private;
807 pte_t *pte;
808 int err = 0;
809 pagemap_entry_t pme = make_pme(PM_NOT_PRESENT);
810
811 /* find the first VMA at or above 'addr' */
812 vma = find_vma(walk->mm, addr);
813 if (vma && pmd_trans_huge_lock(pmd, vma) == 1) {
814 for (; addr != end; addr += PAGE_SIZE) {
815 unsigned long offset;
816
817 offset = (addr & ~PAGEMAP_WALK_MASK) >>
818 PAGE_SHIFT;
819 thp_pmd_to_pagemap_entry(&pme, *pmd, offset);
820 err = add_to_pagemap(addr, &pme, pm);
821 if (err)
822 break;
823 }
824 spin_unlock(&walk->mm->page_table_lock);
825 return err;
826 }
827
828 if (pmd_trans_unstable(pmd))
829 return 0;
830 for (; addr != end; addr += PAGE_SIZE) {
831
832 /* check to see if we've left 'vma' behind
833 * and need a new, higher one */
834 if (vma && (addr >= vma->vm_end)) {
835 vma = find_vma(walk->mm, addr);
836 pme = make_pme(PM_NOT_PRESENT);
837 }
838
839 /* check that 'vma' actually covers this address,
840 * and that it isn't a huge page vma */
841 if (vma && (vma->vm_start <= addr) &&
842 !is_vm_hugetlb_page(vma)) {
843 pte = pte_offset_map(pmd, addr);
844 pte_to_pagemap_entry(&pme, vma, addr, *pte);
845 /* unmap before userspace copy */
846 pte_unmap(pte);
847 }
848 err = add_to_pagemap(addr, &pme, pm);
849 if (err)
850 return err;
851 }
852
853 cond_resched();
854
855 return err;
856}
857
858#ifdef CONFIG_HUGETLB_PAGE
859static void huge_pte_to_pagemap_entry(pagemap_entry_t *pme,
860 pte_t pte, int offset)
861{
862 if (pte_present(pte))
863 *pme = make_pme(PM_PFRAME(pte_pfn(pte) + offset)
864 | PM_PSHIFT(PAGE_SHIFT) | PM_PRESENT);
865 else
866 *pme = make_pme(PM_NOT_PRESENT);
867}
868
869/* This function walks within one hugetlb entry in the single call */
870static int pagemap_hugetlb_range(pte_t *pte, unsigned long hmask,
871 unsigned long addr, unsigned long end,
872 struct mm_walk *walk)
873{
874 struct pagemapread *pm = walk->private;
875 int err = 0;
876 pagemap_entry_t pme;
877
878 for (; addr != end; addr += PAGE_SIZE) {
879 int offset = (addr & ~hmask) >> PAGE_SHIFT;
880 huge_pte_to_pagemap_entry(&pme, *pte, offset);
881 err = add_to_pagemap(addr, &pme, pm);
882 if (err)
883 return err;
884 }
885
886 cond_resched();
887
888 return err;
889}
890#endif /* HUGETLB_PAGE */
891
892/*
893 * /proc/pid/pagemap - an array mapping virtual pages to pfns
894 *
895 * For each page in the address space, this file contains one 64-bit entry
896 * consisting of the following:
897 *
898 * Bits 0-54 page frame number (PFN) if present
899 * Bits 0-4 swap type if swapped
900 * Bits 5-54 swap offset if swapped
901 * Bits 55-60 page shift (page size = 1<<page shift)
902 * Bit 61 page is file-page or shared-anon
903 * Bit 62 page swapped
904 * Bit 63 page present
905 *
906 * If the page is not present but in swap, then the PFN contains an
907 * encoding of the swap file number and the page's offset into the
908 * swap. Unmapped pages return a null PFN. This allows determining
909 * precisely which pages are mapped (or in swap) and comparing mapped
910 * pages between processes.
911 *
912 * Efficient users of this interface will use /proc/pid/maps to
913 * determine which areas of memory are actually mapped and llseek to
914 * skip over unmapped regions.
915 */
916static ssize_t pagemap_read(struct file *file, char __user *buf,
917 size_t count, loff_t *ppos)
918{
919 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
920 struct mm_struct *mm;
921 struct pagemapread pm;
922 int ret = -ESRCH;
923 struct mm_walk pagemap_walk = {};
924 unsigned long src;
925 unsigned long svpfn;
926 unsigned long start_vaddr;
927 unsigned long end_vaddr;
928 int copied = 0;
929
930 if (!task)
931 goto out;
932
933 ret = -EINVAL;
934 /* file position must be aligned */
935 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
936 goto out_task;
937
938 ret = 0;
939 if (!count)
940 goto out_task;
941
942 pm.len = PM_ENTRY_BYTES * (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
943 pm.buffer = kmalloc(pm.len, GFP_TEMPORARY);
944 ret = -ENOMEM;
945 if (!pm.buffer)
946 goto out_task;
947
948 mm = mm_access(task, PTRACE_MODE_READ);
949 ret = PTR_ERR(mm);
950 if (!mm || IS_ERR(mm))
951 goto out_free;
952
953 pagemap_walk.pmd_entry = pagemap_pte_range;
954 pagemap_walk.pte_hole = pagemap_pte_hole;
955#ifdef CONFIG_HUGETLB_PAGE
956 pagemap_walk.hugetlb_entry = pagemap_hugetlb_range;
957#endif
958 pagemap_walk.mm = mm;
959 pagemap_walk.private = ±
960
961 src = *ppos;
962 svpfn = src / PM_ENTRY_BYTES;
963 start_vaddr = svpfn << PAGE_SHIFT;
964 end_vaddr = TASK_SIZE_OF(task);
965
966 /* watch out for wraparound */
967 if (svpfn > TASK_SIZE_OF(task) >> PAGE_SHIFT)
968 start_vaddr = end_vaddr;
969
970 /*
971 * The odds are that this will stop walking way
972 * before end_vaddr, because the length of the
973 * user buffer is tracked in "pm", and the walk
974 * will stop when we hit the end of the buffer.
975 */
976 ret = 0;
977 while (count && (start_vaddr < end_vaddr)) {
978 int len;
979 unsigned long end;
980
981 pm.pos = 0;
982 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
983 /* overflow ? */
984 if (end < start_vaddr || end > end_vaddr)
985 end = end_vaddr;
986 down_read(&mm->mmap_sem);
987 ret = walk_page_range(start_vaddr, end, &pagemap_walk);
988 up_read(&mm->mmap_sem);
989 start_vaddr = end;
990
991 len = min(count, PM_ENTRY_BYTES * pm.pos);
992 if (copy_to_user(buf, pm.buffer, len)) {
993 ret = -EFAULT;
994 goto out_mm;
995 }
996 copied += len;
997 buf += len;
998 count -= len;
999 }
1000 *ppos += copied;
1001 if (!ret || ret == PM_END_OF_BUFFER)
1002 ret = copied;
1003
1004out_mm:
1005 mmput(mm);
1006out_free:
1007 kfree(pm.buffer);
1008out_task:
1009 put_task_struct(task);
1010out:
1011 return ret;
1012}
1013
1014const struct file_operations proc_pagemap_operations = {
1015 .llseek = mem_lseek, /* borrow this */
1016 .read = pagemap_read,
1017};
1018#endif /* CONFIG_PROC_PAGE_MONITOR */
1019
1020#ifdef CONFIG_NUMA
1021
1022struct numa_maps {
1023 struct vm_area_struct *vma;
1024 unsigned long pages;
1025 unsigned long anon;
1026 unsigned long active;
1027 unsigned long writeback;
1028 unsigned long mapcount_max;
1029 unsigned long dirty;
1030 unsigned long swapcache;
1031 unsigned long node[MAX_NUMNODES];
1032};
1033
1034struct numa_maps_private {
1035 struct proc_maps_private proc_maps;
1036 struct numa_maps md;
1037};
1038
1039static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
1040 unsigned long nr_pages)
1041{
1042 int count = page_mapcount(page);
1043
1044 md->pages += nr_pages;
1045 if (pte_dirty || PageDirty(page))
1046 md->dirty += nr_pages;
1047
1048 if (PageSwapCache(page))
1049 md->swapcache += nr_pages;
1050
1051 if (PageActive(page) || PageUnevictable(page))
1052 md->active += nr_pages;
1053
1054 if (PageWriteback(page))
1055 md->writeback += nr_pages;
1056
1057 if (PageAnon(page))
1058 md->anon += nr_pages;
1059
1060 if (count > md->mapcount_max)
1061 md->mapcount_max = count;
1062
1063 md->node[page_to_nid(page)] += nr_pages;
1064}
1065
1066static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
1067 unsigned long addr)
1068{
1069 struct page *page;
1070 int nid;
1071
1072 if (!pte_present(pte))
1073 return NULL;
1074
1075 page = vm_normal_page(vma, addr, pte);
1076 if (!page)
1077 return NULL;
1078
1079 if (PageReserved(page))
1080 return NULL;
1081
1082 nid = page_to_nid(page);
1083 if (!node_isset(nid, node_states[N_HIGH_MEMORY]))
1084 return NULL;
1085
1086 return page;
1087}
1088
1089static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
1090 unsigned long end, struct mm_walk *walk)
1091{
1092 struct numa_maps *md;
1093 spinlock_t *ptl;
1094 pte_t *orig_pte;
1095 pte_t *pte;
1096
1097 md = walk->private;
1098
1099 if (pmd_trans_huge_lock(pmd, md->vma) == 1) {
1100 pte_t huge_pte = *(pte_t *)pmd;
1101 struct page *page;
1102
1103 page = can_gather_numa_stats(huge_pte, md->vma, addr);
1104 if (page)
1105 gather_stats(page, md, pte_dirty(huge_pte),
1106 HPAGE_PMD_SIZE/PAGE_SIZE);
1107 spin_unlock(&walk->mm->page_table_lock);
1108 return 0;
1109 }
1110
1111 if (pmd_trans_unstable(pmd))
1112 return 0;
1113 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
1114 do {
1115 struct page *page = can_gather_numa_stats(*pte, md->vma, addr);
1116 if (!page)
1117 continue;
1118 gather_stats(page, md, pte_dirty(*pte), 1);
1119
1120 } while (pte++, addr += PAGE_SIZE, addr != end);
1121 pte_unmap_unlock(orig_pte, ptl);
1122 return 0;
1123}
1124#ifdef CONFIG_HUGETLB_PAGE
1125static int gather_hugetbl_stats(pte_t *pte, unsigned long hmask,
1126 unsigned long addr, unsigned long end, struct mm_walk *walk)
1127{
1128 struct numa_maps *md;
1129 struct page *page;
1130
1131 if (pte_none(*pte))
1132 return 0;
1133
1134 page = pte_page(*pte);
1135 if (!page)
1136 return 0;
1137
1138 md = walk->private;
1139 gather_stats(page, md, pte_dirty(*pte), 1);
1140 return 0;
1141}
1142
1143#else
1144static int gather_hugetbl_stats(pte_t *pte, unsigned long hmask,
1145 unsigned long addr, unsigned long end, struct mm_walk *walk)
1146{
1147 return 0;
1148}
1149#endif
1150
1151/*
1152 * Display pages allocated per node and memory policy via /proc.
1153 */
1154static int show_numa_map(struct seq_file *m, void *v, int is_pid)
1155{
1156 struct numa_maps_private *numa_priv = m->private;
1157 struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
1158 struct vm_area_struct *vma = v;
1159 struct numa_maps *md = &numa_priv->md;
1160 struct file *file = vma->vm_file;
1161 struct mm_struct *mm = vma->vm_mm;
1162 struct mm_walk walk = {};
1163 struct mempolicy *pol;
1164 int n;
1165 char buffer[50];
1166
1167 if (!mm)
1168 return 0;
1169
1170 /* Ensure we start with an empty set of numa_maps statistics. */
1171 memset(md, 0, sizeof(*md));
1172
1173 md->vma = vma;
1174
1175 walk.hugetlb_entry = gather_hugetbl_stats;
1176 walk.pmd_entry = gather_pte_stats;
1177 walk.private = md;
1178 walk.mm = mm;
1179
1180 pol = get_vma_policy(proc_priv->task, vma, vma->vm_start);
1181 mpol_to_str(buffer, sizeof(buffer), pol, 0);
1182 mpol_cond_put(pol);
1183
1184 seq_printf(m, "%08lx %s", vma->vm_start, buffer);
1185
1186 if (file) {
1187 seq_printf(m, " file=");
1188 seq_path(m, &file->f_path, "\n\t= ");
1189 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1190 seq_printf(m, " heap");
1191 } else {
1192 pid_t tid = vm_is_stack(proc_priv->task, vma, is_pid);
1193 if (tid != 0) {
1194 /*
1195 * Thread stack in /proc/PID/task/TID/maps or
1196 * the main process stack.
1197 */
1198 if (!is_pid || (vma->vm_start <= mm->start_stack &&
1199 vma->vm_end >= mm->start_stack))
1200 seq_printf(m, " stack");
1201 else
1202 seq_printf(m, " stack:%d", tid);
1203 }
1204 }
1205
1206 if (is_vm_hugetlb_page(vma))
1207 seq_printf(m, " huge");
1208
1209 walk_page_range(vma->vm_start, vma->vm_end, &walk);
1210
1211 if (!md->pages)
1212 goto out;
1213
1214 if (md->anon)
1215 seq_printf(m, " anon=%lu", md->anon);
1216
1217 if (md->dirty)
1218 seq_printf(m, " dirty=%lu", md->dirty);
1219
1220 if (md->pages != md->anon && md->pages != md->dirty)
1221 seq_printf(m, " mapped=%lu", md->pages);
1222
1223 if (md->mapcount_max > 1)
1224 seq_printf(m, " mapmax=%lu", md->mapcount_max);
1225
1226 if (md->swapcache)
1227 seq_printf(m, " swapcache=%lu", md->swapcache);
1228
1229 if (md->active < md->pages && !is_vm_hugetlb_page(vma))
1230 seq_printf(m, " active=%lu", md->active);
1231
1232 if (md->writeback)
1233 seq_printf(m, " writeback=%lu", md->writeback);
1234
1235 for_each_node_state(n, N_HIGH_MEMORY)
1236 if (md->node[n])
1237 seq_printf(m, " N%d=%lu", n, md->node[n]);
1238out:
1239 seq_putc(m, '\n');
1240
1241 if (m->count < m->size)
1242 m->version = (vma != proc_priv->tail_vma) ? vma->vm_start : 0;
1243 return 0;
1244}
1245
1246static int show_pid_numa_map(struct seq_file *m, void *v)
1247{
1248 return show_numa_map(m, v, 1);
1249}
1250
1251static int show_tid_numa_map(struct seq_file *m, void *v)
1252{
1253 return show_numa_map(m, v, 0);
1254}
1255
1256static const struct seq_operations proc_pid_numa_maps_op = {
1257 .start = m_start,
1258 .next = m_next,
1259 .stop = m_stop,
1260 .show = show_pid_numa_map,
1261};
1262
1263static const struct seq_operations proc_tid_numa_maps_op = {
1264 .start = m_start,
1265 .next = m_next,
1266 .stop = m_stop,
1267 .show = show_tid_numa_map,
1268};
1269
1270static int numa_maps_open(struct inode *inode, struct file *file,
1271 const struct seq_operations *ops)
1272{
1273 struct numa_maps_private *priv;
1274 int ret = -ENOMEM;
1275 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1276 if (priv) {
1277 priv->proc_maps.pid = proc_pid(inode);
1278 ret = seq_open(file, ops);
1279 if (!ret) {
1280 struct seq_file *m = file->private_data;
1281 m->private = priv;
1282 } else {
1283 kfree(priv);
1284 }
1285 }
1286 return ret;
1287}
1288
1289static int pid_numa_maps_open(struct inode *inode, struct file *file)
1290{
1291 return numa_maps_open(inode, file, &proc_pid_numa_maps_op);
1292}
1293
1294static int tid_numa_maps_open(struct inode *inode, struct file *file)
1295{
1296 return numa_maps_open(inode, file, &proc_tid_numa_maps_op);
1297}
1298
1299const struct file_operations proc_pid_numa_maps_operations = {
1300 .open = pid_numa_maps_open,
1301 .read = seq_read,
1302 .llseek = seq_lseek,
1303 .release = seq_release_private,
1304};
1305
1306const struct file_operations proc_tid_numa_maps_operations = {
1307 .open = tid_numa_maps_open,
1308 .read = seq_read,
1309 .llseek = seq_lseek,
1310 .release = seq_release_private,
1311};
1312#endif /* CONFIG_NUMA */