Linux Kernel  3.7.1
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
page-types.c
Go to the documentation of this file.
1 /*
2  * page-types: Tool for querying page flags
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms of the GNU General Public License as published by the Free
6  * Software Foundation; version 2.
7  *
8  * This program is distributed in the hope that it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
11  * more details.
12  *
13  * You should find a copy of v2 of the GNU General Public License somewhere on
14  * your Linux system; if not, write to the Free Software Foundation, Inc., 59
15  * Temple Place, Suite 330, Boston, MA 02111-1307 USA.
16  *
17  * Copyright (C) 2009 Intel corporation
18  *
19  * Authors: Wu Fengguang <[email protected]>
20  */
21 
22 #define _LARGEFILE64_SOURCE
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <unistd.h>
26 #include <stdint.h>
27 #include <stdarg.h>
28 #include <string.h>
29 #include <getopt.h>
30 #include <limits.h>
31 #include <assert.h>
32 #include <sys/types.h>
33 #include <sys/errno.h>
34 #include <sys/fcntl.h>
35 #include <sys/mount.h>
36 #include <sys/statfs.h>
37 #include "../../include/uapi/linux/magic.h"
38 #include "../../include/uapi/linux/kernel-page-flags.h"
39 
40 
41 #ifndef MAX_PATH
42 # define MAX_PATH 256
43 #endif
44 
45 #ifndef STR
46 # define _STR(x) #x
47 # define STR(x) _STR(x)
48 #endif
49 
50 /*
51  * pagemap kernel ABI bits
52  */
53 
54 #define PM_ENTRY_BYTES sizeof(uint64_t)
55 #define PM_STATUS_BITS 3
56 #define PM_STATUS_OFFSET (64 - PM_STATUS_BITS)
57 #define PM_STATUS_MASK (((1LL << PM_STATUS_BITS) - 1) << PM_STATUS_OFFSET)
58 #define PM_STATUS(nr) (((nr) << PM_STATUS_OFFSET) & PM_STATUS_MASK)
59 #define PM_PSHIFT_BITS 6
60 #define PM_PSHIFT_OFFSET (PM_STATUS_OFFSET - PM_PSHIFT_BITS)
61 #define PM_PSHIFT_MASK (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET)
62 #define PM_PSHIFT(x) (((u64) (x) << PM_PSHIFT_OFFSET) & PM_PSHIFT_MASK)
63 #define PM_PFRAME_MASK ((1LL << PM_PSHIFT_OFFSET) - 1)
64 #define PM_PFRAME(x) ((x) & PM_PFRAME_MASK)
65 
66 #define PM_PRESENT PM_STATUS(4LL)
67 #define PM_SWAP PM_STATUS(2LL)
68 
69 
70 /*
71  * kernel page flags
72  */
73 
74 #define KPF_BYTES 8
75 #define PROC_KPAGEFLAGS "/proc/kpageflags"
76 
77 /* [32-] kernel hacking assistances */
78 #define KPF_RESERVED 32
79 #define KPF_MLOCKED 33
80 #define KPF_MAPPEDTODISK 34
81 #define KPF_PRIVATE 35
82 #define KPF_PRIVATE_2 36
83 #define KPF_OWNER_PRIVATE 37
84 #define KPF_ARCH 38
85 #define KPF_UNCACHED 39
86 
87 /* [48-] take some arbitrary free slots for expanding overloaded flags
88  * not part of kernel API
89  */
90 #define KPF_READAHEAD 48
91 #define KPF_SLOB_FREE 49
92 #define KPF_SLUB_FROZEN 50
93 #define KPF_SLUB_DEBUG 51
94 
95 #define KPF_ALL_BITS ((uint64_t)~0ULL)
96 #define KPF_HACKERS_BITS (0xffffULL << 32)
97 #define KPF_OVERLOADED_BITS (0xffffULL << 48)
98 #define BIT(name) (1ULL << KPF_##name)
99 #define BITS_COMPOUND (BIT(COMPOUND_HEAD) | BIT(COMPOUND_TAIL))
100 
101 static const char * const page_flag_names[] = {
102  [KPF_LOCKED] = "L:locked",
103  [KPF_ERROR] = "E:error",
104  [KPF_REFERENCED] = "R:referenced",
105  [KPF_UPTODATE] = "U:uptodate",
106  [KPF_DIRTY] = "D:dirty",
107  [KPF_LRU] = "l:lru",
108  [KPF_ACTIVE] = "A:active",
109  [KPF_SLAB] = "S:slab",
110  [KPF_WRITEBACK] = "W:writeback",
111  [KPF_RECLAIM] = "I:reclaim",
112  [KPF_BUDDY] = "B:buddy",
113 
114  [KPF_MMAP] = "M:mmap",
115  [KPF_ANON] = "a:anonymous",
116  [KPF_SWAPCACHE] = "s:swapcache",
117  [KPF_SWAPBACKED] = "b:swapbacked",
118  [KPF_COMPOUND_HEAD] = "H:compound_head",
119  [KPF_COMPOUND_TAIL] = "T:compound_tail",
120  [KPF_HUGE] = "G:huge",
121  [KPF_UNEVICTABLE] = "u:unevictable",
122  [KPF_HWPOISON] = "X:hwpoison",
123  [KPF_NOPAGE] = "n:nopage",
124  [KPF_KSM] = "x:ksm",
125  [KPF_THP] = "t:thp",
126 
127  [KPF_RESERVED] = "r:reserved",
128  [KPF_MLOCKED] = "m:mlocked",
129  [KPF_MAPPEDTODISK] = "d:mappedtodisk",
130  [KPF_PRIVATE] = "P:private",
131  [KPF_PRIVATE_2] = "p:private_2",
132  [KPF_OWNER_PRIVATE] = "O:owner_private",
133  [KPF_ARCH] = "h:arch",
134  [KPF_UNCACHED] = "c:uncached",
135 
136  [KPF_READAHEAD] = "I:readahead",
137  [KPF_SLOB_FREE] = "P:slob_free",
138  [KPF_SLUB_FROZEN] = "A:slub_frozen",
139  [KPF_SLUB_DEBUG] = "E:slub_debug",
140 };
141 
142 
143 static const char * const debugfs_known_mountpoints[] = {
144  "/sys/kernel/debug",
145  "/debug",
146  0,
147 };
148 
149 /*
150  * data structures
151  */
152 
153 static int opt_raw; /* for kernel developers */
154 static int opt_list; /* list pages (in ranges) */
155 static int opt_no_summary; /* don't show summary */
156 static pid_t opt_pid; /* process to walk */
157 
158 #define MAX_ADDR_RANGES 1024
159 static int nr_addr_ranges;
160 static unsigned long opt_offset[MAX_ADDR_RANGES];
161 static unsigned long opt_size[MAX_ADDR_RANGES];
162 
163 #define MAX_VMAS 10240
164 static int nr_vmas;
165 static unsigned long pg_start[MAX_VMAS];
166 static unsigned long pg_end[MAX_VMAS];
167 
168 #define MAX_BIT_FILTERS 64
169 static int nr_bit_filters;
170 static uint64_t opt_mask[MAX_BIT_FILTERS];
171 static uint64_t opt_bits[MAX_BIT_FILTERS];
172 
173 static int page_size;
174 
175 static int pagemap_fd;
176 static int kpageflags_fd;
177 
178 static int opt_hwpoison;
179 static int opt_unpoison;
180 
181 static char hwpoison_debug_fs[MAX_PATH+1];
182 static int hwpoison_inject_fd;
183 static int hwpoison_forget_fd;
184 
185 #define HASH_SHIFT 13
186 #define HASH_SIZE (1 << HASH_SHIFT)
187 #define HASH_MASK (HASH_SIZE - 1)
188 #define HASH_KEY(flags) (flags & HASH_MASK)
189 
190 static unsigned long total_pages;
191 static unsigned long nr_pages[HASH_SIZE];
192 static uint64_t page_flags[HASH_SIZE];
193 
194 
195 /*
196  * helper functions
197  */
198 
199 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
200 
201 #define min_t(type, x, y) ({ \
202  type __min1 = (x); \
203  type __min2 = (y); \
204  __min1 < __min2 ? __min1 : __min2; })
205 
206 #define max_t(type, x, y) ({ \
207  type __max1 = (x); \
208  type __max2 = (y); \
209  __max1 > __max2 ? __max1 : __max2; })
210 
211 static unsigned long pages2mb(unsigned long pages)
212 {
213  return (pages * page_size) >> 20;
214 }
215 
216 static void fatal(const char *x, ...)
217 {
218  va_list ap;
219 
220  va_start(ap, x);
221  vfprintf(stderr, x, ap);
222  va_end(ap);
223  exit(EXIT_FAILURE);
224 }
225 
226 static int checked_open(const char *pathname, int flags)
227 {
228  int fd = open(pathname, flags);
229 
230  if (fd < 0) {
231  perror(pathname);
232  exit(EXIT_FAILURE);
233  }
234 
235  return fd;
236 }
237 
238 /*
239  * pagemap/kpageflags routines
240  */
241 
242 static unsigned long do_u64_read(int fd, char *name,
243  uint64_t *buf,
244  unsigned long index,
245  unsigned long count)
246 {
247  long bytes;
248 
249  if (index > ULONG_MAX / 8)
250  fatal("index overflow: %lu\n", index);
251 
252  if (lseek(fd, index * 8, SEEK_SET) < 0) {
253  perror(name);
254  exit(EXIT_FAILURE);
255  }
256 
257  bytes = read(fd, buf, count * 8);
258  if (bytes < 0) {
259  perror(name);
260  exit(EXIT_FAILURE);
261  }
262  if (bytes % 8)
263  fatal("partial read: %lu bytes\n", bytes);
264 
265  return bytes / 8;
266 }
267 
268 static unsigned long kpageflags_read(uint64_t *buf,
269  unsigned long index,
270  unsigned long pages)
271 {
272  return do_u64_read(kpageflags_fd, PROC_KPAGEFLAGS, buf, index, pages);
273 }
274 
275 static unsigned long pagemap_read(uint64_t *buf,
276  unsigned long index,
277  unsigned long pages)
278 {
279  return do_u64_read(pagemap_fd, "/proc/pid/pagemap", buf, index, pages);
280 }
281 
282 static unsigned long pagemap_pfn(uint64_t val)
283 {
284  unsigned long pfn;
285 
286  if (val & PM_PRESENT)
287  pfn = PM_PFRAME(val);
288  else
289  pfn = 0;
290 
291  return pfn;
292 }
293 
294 
295 /*
296  * page flag names
297  */
298 
299 static char *page_flag_name(uint64_t flags)
300 {
301  static char buf[65];
302  int present;
303  size_t i, j;
304 
305  for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
306  present = (flags >> i) & 1;
307  if (!page_flag_names[i]) {
308  if (present)
309  fatal("unknown flag bit %d\n", i);
310  continue;
311  }
312  buf[j++] = present ? page_flag_names[i][0] : '_';
313  }
314 
315  return buf;
316 }
317 
318 static char *page_flag_longname(uint64_t flags)
319 {
320  static char buf[1024];
321  size_t i, n;
322 
323  for (i = 0, n = 0; i < ARRAY_SIZE(page_flag_names); i++) {
324  if (!page_flag_names[i])
325  continue;
326  if ((flags >> i) & 1)
327  n += snprintf(buf + n, sizeof(buf) - n, "%s,",
328  page_flag_names[i] + 2);
329  }
330  if (n)
331  n--;
332  buf[n] = '\0';
333 
334  return buf;
335 }
336 
337 
338 /*
339  * page list and summary
340  */
341 
342 static void show_page_range(unsigned long voffset,
343  unsigned long offset, uint64_t flags)
344 {
345  static uint64_t flags0;
346  static unsigned long voff;
347  static unsigned long index;
348  static unsigned long count;
349 
350  if (flags == flags0 && offset == index + count &&
351  (!opt_pid || voffset == voff + count)) {
352  count++;
353  return;
354  }
355 
356  if (count) {
357  if (opt_pid)
358  printf("%lx\t", voff);
359  printf("%lx\t%lx\t%s\n",
360  index, count, page_flag_name(flags0));
361  }
362 
363  flags0 = flags;
364  index = offset;
365  voff = voffset;
366  count = 1;
367 }
368 
369 static void show_page(unsigned long voffset,
370  unsigned long offset, uint64_t flags)
371 {
372  if (opt_pid)
373  printf("%lx\t", voffset);
374  printf("%lx\t%s\n", offset, page_flag_name(flags));
375 }
376 
377 static void show_summary(void)
378 {
379  size_t i;
380 
381  printf(" flags\tpage-count MB"
382  " symbolic-flags\t\t\tlong-symbolic-flags\n");
383 
384  for (i = 0; i < ARRAY_SIZE(nr_pages); i++) {
385  if (nr_pages[i])
386  printf("0x%016llx\t%10lu %8lu %s\t%s\n",
387  (unsigned long long)page_flags[i],
388  nr_pages[i],
389  pages2mb(nr_pages[i]),
390  page_flag_name(page_flags[i]),
391  page_flag_longname(page_flags[i]));
392  }
393 
394  printf(" total\t%10lu %8lu\n",
395  total_pages, pages2mb(total_pages));
396 }
397 
398 
399 /*
400  * page flag filters
401  */
402 
403 static int bit_mask_ok(uint64_t flags)
404 {
405  int i;
406 
407  for (i = 0; i < nr_bit_filters; i++) {
408  if (opt_bits[i] == KPF_ALL_BITS) {
409  if ((flags & opt_mask[i]) == 0)
410  return 0;
411  } else {
412  if ((flags & opt_mask[i]) != opt_bits[i])
413  return 0;
414  }
415  }
416 
417  return 1;
418 }
419 
420 static uint64_t expand_overloaded_flags(uint64_t flags)
421 {
422  /* SLOB/SLUB overload several page flags */
423  if (flags & BIT(SLAB)) {
424  if (flags & BIT(PRIVATE))
425  flags ^= BIT(PRIVATE) | BIT(SLOB_FREE);
426  if (flags & BIT(ACTIVE))
427  flags ^= BIT(ACTIVE) | BIT(SLUB_FROZEN);
428  if (flags & BIT(ERROR))
429  flags ^= BIT(ERROR) | BIT(SLUB_DEBUG);
430  }
431 
432  /* PG_reclaim is overloaded as PG_readahead in the read path */
433  if ((flags & (BIT(RECLAIM) | BIT(WRITEBACK))) == BIT(RECLAIM))
434  flags ^= BIT(RECLAIM) | BIT(READAHEAD);
435 
436  return flags;
437 }
438 
439 static uint64_t well_known_flags(uint64_t flags)
440 {
441  /* hide flags intended only for kernel hacker */
442  flags &= ~KPF_HACKERS_BITS;
443 
444  /* hide non-hugeTLB compound pages */
445  if ((flags & BITS_COMPOUND) && !(flags & BIT(HUGE)))
446  flags &= ~BITS_COMPOUND;
447 
448  return flags;
449 }
450 
451 static uint64_t kpageflags_flags(uint64_t flags)
452 {
453  flags = expand_overloaded_flags(flags);
454 
455  if (!opt_raw)
456  flags = well_known_flags(flags);
457 
458  return flags;
459 }
460 
461 /* verify that a mountpoint is actually a debugfs instance */
462 static int debugfs_valid_mountpoint(const char *debugfs)
463 {
464  struct statfs st_fs;
465 
466  if (statfs(debugfs, &st_fs) < 0)
467  return -ENOENT;
468  else if (st_fs.f_type != (long) DEBUGFS_MAGIC)
469  return -ENOENT;
470 
471  return 0;
472 }
473 
474 /* find the path to the mounted debugfs */
475 static const char *debugfs_find_mountpoint(void)
476 {
477  const char *const *ptr;
478  char type[100];
479  FILE *fp;
480 
481  ptr = debugfs_known_mountpoints;
482  while (*ptr) {
483  if (debugfs_valid_mountpoint(*ptr) == 0) {
484  strcpy(hwpoison_debug_fs, *ptr);
485  return hwpoison_debug_fs;
486  }
487  ptr++;
488  }
489 
490  /* give up and parse /proc/mounts */
491  fp = fopen("/proc/mounts", "r");
492  if (fp == NULL)
493  perror("Can't open /proc/mounts for read");
494 
495  while (fscanf(fp, "%*s %"
496  STR(MAX_PATH)
497  "s %99s %*s %*d %*d\n",
498  hwpoison_debug_fs, type) == 2) {
499  if (strcmp(type, "debugfs") == 0)
500  break;
501  }
502  fclose(fp);
503 
504  if (strcmp(type, "debugfs") != 0)
505  return NULL;
506 
507  return hwpoison_debug_fs;
508 }
509 
510 /* mount the debugfs somewhere if it's not mounted */
511 
512 static void debugfs_mount(void)
513 {
514  const char *const *ptr;
515 
516  /* see if it's already mounted */
518  return;
519 
520  ptr = debugfs_known_mountpoints;
521  while (*ptr) {
522  if (mount(NULL, *ptr, "debugfs", 0, NULL) == 0) {
523  /* save the mountpoint */
524  strcpy(hwpoison_debug_fs, *ptr);
525  break;
526  }
527  ptr++;
528  }
529 
530  if (*ptr == NULL) {
531  perror("mount debugfs");
532  exit(EXIT_FAILURE);
533  }
534 }
535 
536 /*
537  * page actions
538  */
539 
540 static void prepare_hwpoison_fd(void)
541 {
542  char buf[MAX_PATH + 1];
543 
544  debugfs_mount();
545 
546  if (opt_hwpoison && !hwpoison_inject_fd) {
547  snprintf(buf, MAX_PATH, "%s/hwpoison/corrupt-pfn",
548  hwpoison_debug_fs);
549  hwpoison_inject_fd = checked_open(buf, O_WRONLY);
550  }
551 
552  if (opt_unpoison && !hwpoison_forget_fd) {
553  snprintf(buf, MAX_PATH, "%s/hwpoison/unpoison-pfn",
554  hwpoison_debug_fs);
555  hwpoison_forget_fd = checked_open(buf, O_WRONLY);
556  }
557 }
558 
559 static int hwpoison_page(unsigned long offset)
560 {
561  char buf[100];
562  int len;
563 
564  len = sprintf(buf, "0x%lx\n", offset);
565  len = write(hwpoison_inject_fd, buf, len);
566  if (len < 0) {
567  perror("hwpoison inject");
568  return len;
569  }
570  return 0;
571 }
572 
573 static int unpoison_page(unsigned long offset)
574 {
575  char buf[100];
576  int len;
577 
578  len = sprintf(buf, "0x%lx\n", offset);
579  len = write(hwpoison_forget_fd, buf, len);
580  if (len < 0) {
581  perror("hwpoison forget");
582  return len;
583  }
584  return 0;
585 }
586 
587 /*
588  * page frame walker
589  */
590 
591 static size_t hash_slot(uint64_t flags)
592 {
593  size_t k = HASH_KEY(flags);
594  size_t i;
595 
596  /* Explicitly reserve slot 0 for flags 0: the following logic
597  * cannot distinguish an unoccupied slot from slot (flags==0).
598  */
599  if (flags == 0)
600  return 0;
601 
602  /* search through the remaining (HASH_SIZE-1) slots */
603  for (i = 1; i < ARRAY_SIZE(page_flags); i++, k++) {
604  if (!k || k >= ARRAY_SIZE(page_flags))
605  k = 1;
606  if (page_flags[k] == 0) {
607  page_flags[k] = flags;
608  return k;
609  }
610  if (page_flags[k] == flags)
611  return k;
612  }
613 
614  fatal("hash table full: bump up HASH_SHIFT?\n");
615  exit(EXIT_FAILURE);
616 }
617 
618 static void add_page(unsigned long voffset,
619  unsigned long offset, uint64_t flags)
620 {
621  flags = kpageflags_flags(flags);
622 
623  if (!bit_mask_ok(flags))
624  return;
625 
626  if (opt_hwpoison)
627  hwpoison_page(offset);
628  if (opt_unpoison)
629  unpoison_page(offset);
630 
631  if (opt_list == 1)
632  show_page_range(voffset, offset, flags);
633  else if (opt_list == 2)
634  show_page(voffset, offset, flags);
635 
636  nr_pages[hash_slot(flags)]++;
637  total_pages++;
638 }
639 
640 #define KPAGEFLAGS_BATCH (64 << 10) /* 64k pages */
641 static void walk_pfn(unsigned long voffset,
642  unsigned long index,
643  unsigned long count)
644 {
646  unsigned long batch;
647  unsigned long pages;
648  unsigned long i;
649 
650  while (count) {
651  batch = min_t(unsigned long, count, KPAGEFLAGS_BATCH);
652  pages = kpageflags_read(buf, index, batch);
653  if (pages == 0)
654  break;
655 
656  for (i = 0; i < pages; i++)
657  add_page(voffset + i, index + i, buf[i]);
658 
659  index += pages;
660  count -= pages;
661  }
662 }
663 
664 #define PAGEMAP_BATCH (64 << 10)
665 static void walk_vma(unsigned long index, unsigned long count)
666 {
667  uint64_t buf[PAGEMAP_BATCH];
668  unsigned long batch;
669  unsigned long pages;
670  unsigned long pfn;
671  unsigned long i;
672 
673  while (count) {
674  batch = min_t(unsigned long, count, PAGEMAP_BATCH);
675  pages = pagemap_read(buf, index, batch);
676  if (pages == 0)
677  break;
678 
679  for (i = 0; i < pages; i++) {
680  pfn = pagemap_pfn(buf[i]);
681  if (pfn)
682  walk_pfn(index + i, pfn, 1);
683  }
684 
685  index += pages;
686  count -= pages;
687  }
688 }
689 
690 static void walk_task(unsigned long index, unsigned long count)
691 {
692  const unsigned long end = index + count;
693  unsigned long start;
694  int i = 0;
695 
696  while (index < end) {
697 
698  while (pg_end[i] <= index)
699  if (++i >= nr_vmas)
700  return;
701  if (pg_start[i] >= end)
702  return;
703 
704  start = max_t(unsigned long, pg_start[i], index);
705  index = min_t(unsigned long, pg_end[i], end);
706 
707  assert(start < index);
708  walk_vma(start, index - start);
709  }
710 }
711 
712 static void add_addr_range(unsigned long offset, unsigned long size)
713 {
714  if (nr_addr_ranges >= MAX_ADDR_RANGES)
715  fatal("too many addr ranges\n");
716 
717  opt_offset[nr_addr_ranges] = offset;
718  opt_size[nr_addr_ranges] = min_t(unsigned long, size, ULONG_MAX-offset);
719  nr_addr_ranges++;
720 }
721 
722 static void walk_addr_ranges(void)
723 {
724  int i;
725 
726  kpageflags_fd = checked_open(PROC_KPAGEFLAGS, O_RDONLY);
727 
728  if (!nr_addr_ranges)
729  add_addr_range(0, ULONG_MAX);
730 
731  for (i = 0; i < nr_addr_ranges; i++)
732  if (!opt_pid)
733  walk_pfn(0, opt_offset[i], opt_size[i]);
734  else
735  walk_task(opt_offset[i], opt_size[i]);
736 
737  close(kpageflags_fd);
738 }
739 
740 
741 /*
742  * user interface
743  */
744 
745 static const char *page_flag_type(uint64_t flag)
746 {
747  if (flag & KPF_HACKERS_BITS)
748  return "(r)";
749  if (flag & KPF_OVERLOADED_BITS)
750  return "(o)";
751  return " ";
752 }
753 
754 static void usage(void)
755 {
756  size_t i, j;
757 
758  printf(
759 "page-types [options]\n"
760 " -r|--raw Raw mode, for kernel developers\n"
761 " -d|--describe flags Describe flags\n"
762 " -a|--addr addr-spec Walk a range of pages\n"
763 " -b|--bits bits-spec Walk pages with specified bits\n"
764 " -p|--pid pid Walk process address space\n"
765 #if 0 /* planned features */
766 " -f|--file filename Walk file address space\n"
767 #endif
768 " -l|--list Show page details in ranges\n"
769 " -L|--list-each Show page details one by one\n"
770 " -N|--no-summary Don't show summary info\n"
771 " -X|--hwpoison hwpoison pages\n"
772 " -x|--unpoison unpoison pages\n"
773 " -h|--help Show this usage message\n"
774 "flags:\n"
775 " 0x10 bitfield format, e.g.\n"
776 " anon bit-name, e.g.\n"
777 " 0x10,anon comma-separated list, e.g.\n"
778 "addr-spec:\n"
779 " N one page at offset N (unit: pages)\n"
780 " N+M pages range from N to N+M-1\n"
781 " N,M pages range from N to M-1\n"
782 " N, pages range from N to end\n"
783 " ,M pages range from 0 to M-1\n"
784 "bits-spec:\n"
785 " bit1,bit2 (flags & (bit1|bit2)) != 0\n"
786 " bit1,bit2=bit1 (flags & (bit1|bit2)) == bit1\n"
787 " bit1,~bit2 (flags & (bit1|bit2)) == bit1\n"
788 " =bit1,bit2 flags == (bit1|bit2)\n"
789 "bit-names:\n"
790  );
791 
792  for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
793  if (!page_flag_names[i])
794  continue;
795  printf("%16s%s", page_flag_names[i] + 2,
796  page_flag_type(1ULL << i));
797  if (++j > 3) {
798  j = 0;
799  putchar('\n');
800  }
801  }
802  printf("\n "
803  "(r) raw mode bits (o) overloaded bits\n");
804 }
805 
806 static unsigned long long parse_number(const char *str)
807 {
808  unsigned long long n;
809 
810  n = strtoll(str, NULL, 0);
811 
812  if (n == 0 && str[0] != '0')
813  fatal("invalid name or number: %s\n", str);
814 
815  return n;
816 }
817 
818 static void parse_pid(const char *str)
819 {
820  FILE *file;
821  char buf[5000];
822 
823  opt_pid = parse_number(str);
824 
825  sprintf(buf, "/proc/%d/pagemap", opt_pid);
826  pagemap_fd = checked_open(buf, O_RDONLY);
827 
828  sprintf(buf, "/proc/%d/maps", opt_pid);
829  file = fopen(buf, "r");
830  if (!file) {
831  perror(buf);
832  exit(EXIT_FAILURE);
833  }
834 
835  while (fgets(buf, sizeof(buf), file) != NULL) {
836  unsigned long vm_start;
837  unsigned long vm_end;
838  unsigned long long pgoff;
839  int major, minor;
840  char r, w, x, s;
841  unsigned long ino;
842  int n;
843 
844  n = sscanf(buf, "%lx-%lx %c%c%c%c %llx %x:%x %lu",
845  &vm_start,
846  &vm_end,
847  &r, &w, &x, &s,
848  &pgoff,
849  &major, &minor,
850  &ino);
851  if (n < 10) {
852  fprintf(stderr, "unexpected line: %s\n", buf);
853  continue;
854  }
855  pg_start[nr_vmas] = vm_start / page_size;
856  pg_end[nr_vmas] = vm_end / page_size;
857  if (++nr_vmas >= MAX_VMAS) {
858  fprintf(stderr, "too many VMAs\n");
859  break;
860  }
861  }
862  fclose(file);
863 }
864 
865 static void parse_file(const char *name)
866 {
867 }
868 
869 static void parse_addr_range(const char *optarg)
870 {
871  unsigned long offset;
872  unsigned long size;
873  char *p;
874 
875  p = strchr(optarg, ',');
876  if (!p)
877  p = strchr(optarg, '+');
878 
879  if (p == optarg) {
880  offset = 0;
881  size = parse_number(p + 1);
882  } else if (p) {
883  offset = parse_number(optarg);
884  if (p[1] == '\0')
885  size = ULONG_MAX;
886  else {
887  size = parse_number(p + 1);
888  if (*p == ',') {
889  if (size < offset)
890  fatal("invalid range: %lu,%lu\n",
891  offset, size);
892  size -= offset;
893  }
894  }
895  } else {
896  offset = parse_number(optarg);
897  size = 1;
898  }
899 
900  add_addr_range(offset, size);
901 }
902 
903 static void add_bits_filter(uint64_t mask, uint64_t bits)
904 {
905  if (nr_bit_filters >= MAX_BIT_FILTERS)
906  fatal("too much bit filters\n");
907 
908  opt_mask[nr_bit_filters] = mask;
909  opt_bits[nr_bit_filters] = bits;
910  nr_bit_filters++;
911 }
912 
913 static uint64_t parse_flag_name(const char *str, int len)
914 {
915  size_t i;
916 
917  if (!*str || !len)
918  return 0;
919 
920  if (len <= 8 && !strncmp(str, "compound", len))
921  return BITS_COMPOUND;
922 
923  for (i = 0; i < ARRAY_SIZE(page_flag_names); i++) {
924  if (!page_flag_names[i])
925  continue;
926  if (!strncmp(str, page_flag_names[i] + 2, len))
927  return 1ULL << i;
928  }
929 
930  return parse_number(str);
931 }
932 
933 static uint64_t parse_flag_names(const char *str, int all)
934 {
935  const char *p = str;
936  uint64_t flags = 0;
937 
938  while (1) {
939  if (*p == ',' || *p == '=' || *p == '\0') {
940  if ((*str != '~') || (*str == '~' && all && *++str))
941  flags |= parse_flag_name(str, p - str);
942  if (*p != ',')
943  break;
944  str = p + 1;
945  }
946  p++;
947  }
948 
949  return flags;
950 }
951 
952 static void parse_bits_mask(const char *optarg)
953 {
954  uint64_t mask;
955  uint64_t bits;
956  const char *p;
957 
958  p = strchr(optarg, '=');
959  if (p == optarg) {
960  mask = KPF_ALL_BITS;
961  bits = parse_flag_names(p + 1, 0);
962  } else if (p) {
963  mask = parse_flag_names(optarg, 0);
964  bits = parse_flag_names(p + 1, 0);
965  } else if (strchr(optarg, '~')) {
966  mask = parse_flag_names(optarg, 1);
967  bits = parse_flag_names(optarg, 0);
968  } else {
969  mask = parse_flag_names(optarg, 0);
970  bits = KPF_ALL_BITS;
971  }
972 
973  add_bits_filter(mask, bits);
974 }
975 
976 static void describe_flags(const char *optarg)
977 {
978  uint64_t flags = parse_flag_names(optarg, 0);
979 
980  printf("0x%016llx\t%s\t%s\n",
981  (unsigned long long)flags,
982  page_flag_name(flags),
983  page_flag_longname(flags));
984 }
985 
986 static const struct option opts[] = {
987  { "raw" , 0, NULL, 'r' },
988  { "pid" , 1, NULL, 'p' },
989  { "file" , 1, NULL, 'f' },
990  { "addr" , 1, NULL, 'a' },
991  { "bits" , 1, NULL, 'b' },
992  { "describe" , 1, NULL, 'd' },
993  { "list" , 0, NULL, 'l' },
994  { "list-each" , 0, NULL, 'L' },
995  { "no-summary", 0, NULL, 'N' },
996  { "hwpoison" , 0, NULL, 'X' },
997  { "unpoison" , 0, NULL, 'x' },
998  { "help" , 0, NULL, 'h' },
999  { NULL , 0, NULL, 0 }
1000 };
1001 
1002 int main(int argc, char *argv[])
1003 {
1004  int c;
1005 
1006  page_size = getpagesize();
1007 
1008  while ((c = getopt_long(argc, argv,
1009  "rp:f:a:b:d:lLNXxh", opts, NULL)) != -1) {
1010  switch (c) {
1011  case 'r':
1012  opt_raw = 1;
1013  break;
1014  case 'p':
1015  parse_pid(optarg);
1016  break;
1017  case 'f':
1018  parse_file(optarg);
1019  break;
1020  case 'a':
1021  parse_addr_range(optarg);
1022  break;
1023  case 'b':
1024  parse_bits_mask(optarg);
1025  break;
1026  case 'd':
1027  describe_flags(optarg);
1028  exit(0);
1029  case 'l':
1030  opt_list = 1;
1031  break;
1032  case 'L':
1033  opt_list = 2;
1034  break;
1035  case 'N':
1036  opt_no_summary = 1;
1037  break;
1038  case 'X':
1039  opt_hwpoison = 1;
1040  prepare_hwpoison_fd();
1041  break;
1042  case 'x':
1043  opt_unpoison = 1;
1044  prepare_hwpoison_fd();
1045  break;
1046  case 'h':
1047  usage();
1048  exit(0);
1049  default:
1050  usage();
1051  exit(1);
1052  }
1053  }
1054 
1055  if (opt_list && opt_pid)
1056  printf("voffset\t");
1057  if (opt_list == 1)
1058  printf("offset\tlen\tflags\n");
1059  if (opt_list == 2)
1060  printf("offset\tflags\n");
1061 
1062  walk_addr_ranges();
1063 
1064  if (opt_list == 1)
1065  show_page_range(0, 0, 0); /* drain the buffer */
1066 
1067  if (opt_no_summary)
1068  return 0;
1069 
1070  if (opt_list)
1071  printf("\n\n");
1072 
1073  show_summary();
1074 
1075  return 0;
1076 }