1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * page-types: Tool for querying page flags
4 *
5 * Copyright (C) 2009 Intel corporation
6 *
7 * Authors: Wu Fengguang <fengguang.wu@intel.com>
8 */
9
10 #define _FILE_OFFSET_BITS 64
11 #define _GNU_SOURCE
12 #include <stdio.h>
13 #include <stdlib.h>
14 #include <unistd.h>
15 #include <stdint.h>
16 #include <stdarg.h>
17 #include <string.h>
18 #include <getopt.h>
19 #include <limits.h>
20 #include <assert.h>
21 #include <ftw.h>
22 #include <time.h>
23 #include <setjmp.h>
24 #include <signal.h>
25 #include <sys/types.h>
26 #include <sys/errno.h>
27 #include <sys/fcntl.h>
28 #include <sys/mount.h>
29 #include <sys/statfs.h>
30 #include <sys/mman.h>
31 #include "../../include/uapi/linux/magic.h"
32 #include "../../include/uapi/linux/kernel-page-flags.h"
33 #include <api/fs/fs.h>
34
35 #ifndef MAX_PATH
36 # define MAX_PATH 256
37 #endif
38
39 #ifndef STR
40 # define _STR(x) #x
41 # define STR(x) _STR(x)
42 #endif
43
44 /*
45 * pagemap kernel ABI bits
46 */
47
48 #define PM_ENTRY_BYTES 8
49 #define PM_PFRAME_BITS 55
50 #define PM_PFRAME_MASK ((1LL << PM_PFRAME_BITS) - 1)
51 #define PM_PFRAME(x) ((x) & PM_PFRAME_MASK)
52 #define MAX_SWAPFILES_SHIFT 5
53 #define PM_SWAP_OFFSET(x) (((x) & PM_PFRAME_MASK) >> MAX_SWAPFILES_SHIFT)
54 #define PM_SOFT_DIRTY (1ULL << 55)
55 #define PM_MMAP_EXCLUSIVE (1ULL << 56)
56 #define PM_FILE (1ULL << 61)
57 #define PM_SWAP (1ULL << 62)
58 #define PM_PRESENT (1ULL << 63)
59
60 /*
61 * kernel page flags
62 */
63
64 #define KPF_BYTES 8
65 #define PROC_KPAGEFLAGS "/proc/kpageflags"
66 #define PROC_KPAGECOUNT "/proc/kpagecount"
67 #define PROC_KPAGECGROUP "/proc/kpagecgroup"
68
69 #define SYS_KERNEL_MM_PAGE_IDLE "/sys/kernel/mm/page_idle/bitmap"
70
71 /* [32-] kernel hacking assistances */
72 #define KPF_RESERVED 32
73 #define KPF_MLOCKED 33
74 #define KPF_MAPPEDTODISK 34
75 #define KPF_PRIVATE 35
76 #define KPF_PRIVATE_2 36
77 #define KPF_OWNER_PRIVATE 37
78 #define KPF_ARCH 38
79 #define KPF_UNCACHED 39
80 #define KPF_SOFTDIRTY 40
81 #define KPF_ARCH_2 41
82
83 /* [47-] take some arbitrary free slots for expanding overloaded flags
84 * not part of kernel API
85 */
86 #define KPF_ANON_EXCLUSIVE 47
87 #define KPF_READAHEAD 48
88 #define KPF_SLOB_FREE 49
89 #define KPF_SLUB_FROZEN 50
90 #define KPF_SLUB_DEBUG 51
91 #define KPF_FILE 61
92 #define KPF_SWAP 62
93 #define KPF_MMAP_EXCLUSIVE 63
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 [KPF_OFFLINE] = "o:offline",
127 [KPF_PGTABLE] = "g:pgtable",
128 [KPF_ZERO_PAGE] = "z:zero_page",
129 [KPF_IDLE] = "i:idle_page",
130
131 [KPF_RESERVED] = "r:reserved",
132 [KPF_MLOCKED] = "m:mlocked",
133 [KPF_MAPPEDTODISK] = "d:mappedtodisk",
134 [KPF_PRIVATE] = "P:private",
135 [KPF_PRIVATE_2] = "p:private_2",
136 [KPF_OWNER_PRIVATE] = "O:owner_private",
137 [KPF_ARCH] = "h:arch",
138 [KPF_UNCACHED] = "c:uncached",
139 [KPF_SOFTDIRTY] = "f:softdirty",
140 [KPF_ARCH_2] = "H:arch_2",
141
142 [KPF_ANON_EXCLUSIVE] = "d:anon_exclusive",
143 [KPF_READAHEAD] = "I:readahead",
144 [KPF_SLOB_FREE] = "P:slob_free",
145 [KPF_SLUB_FROZEN] = "A:slub_frozen",
146 [KPF_SLUB_DEBUG] = "E:slub_debug",
147
148 [KPF_FILE] = "F:file",
149 [KPF_SWAP] = "w:swap",
150 [KPF_MMAP_EXCLUSIVE] = "1:mmap_exclusive",
151 };
152
153
154 /*
155 * data structures
156 */
157
158 static int opt_raw; /* for kernel developers */
159 static int opt_list; /* list pages (in ranges) */
160 static int opt_mark_idle; /* set accessed bit */
161 static int opt_no_summary; /* don't show summary */
162 static pid_t opt_pid; /* process to walk */
163 const char *opt_file; /* file or directory path */
164 static uint64_t opt_cgroup; /* cgroup inode */
165 static int opt_list_cgroup;/* list page cgroup */
166 static int opt_list_mapcnt;/* list page map count */
167 static const char *opt_kpageflags;/* kpageflags file to parse */
168
169 #define MAX_ADDR_RANGES 1024
170 static int nr_addr_ranges;
171 static unsigned long opt_offset[MAX_ADDR_RANGES];
172 static unsigned long opt_size[MAX_ADDR_RANGES];
173
174 #define MAX_VMAS 10240
175 static int nr_vmas;
176 static unsigned long pg_start[MAX_VMAS];
177 static unsigned long pg_end[MAX_VMAS];
178
179 #define MAX_BIT_FILTERS 64
180 static int nr_bit_filters;
181 static uint64_t opt_mask[MAX_BIT_FILTERS];
182 static uint64_t opt_bits[MAX_BIT_FILTERS];
183
184 static int page_size;
185
186 static int pagemap_fd;
187 static int kpageflags_fd;
188 static int kpagecount_fd = -1;
189 static int kpagecgroup_fd = -1;
190 static int page_idle_fd = -1;
191
192 static int opt_hwpoison;
193 static int opt_unpoison;
194
195 static const char *hwpoison_debug_fs;
196 static int hwpoison_inject_fd;
197 static int hwpoison_forget_fd;
198
199 #define HASH_SHIFT 13
200 #define HASH_SIZE (1 << HASH_SHIFT)
201 #define HASH_MASK (HASH_SIZE - 1)
202 #define HASH_KEY(flags) (flags & HASH_MASK)
203
204 static unsigned long total_pages;
205 static unsigned long nr_pages[HASH_SIZE];
206 static uint64_t page_flags[HASH_SIZE];
207
208
209 /*
210 * helper functions
211 */
212
213 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
214
215 #define min_t(type, x, y) ({ \
216 type __min1 = (x); \
217 type __min2 = (y); \
218 __min1 < __min2 ? __min1 : __min2; })
219
220 #define max_t(type, x, y) ({ \
221 type __max1 = (x); \
222 type __max2 = (y); \
223 __max1 > __max2 ? __max1 : __max2; })
224
pages2mb(unsigned long pages)225 static unsigned long pages2mb(unsigned long pages)
226 {
227 return (pages * page_size) >> 20;
228 }
229
fatal(const char * x,...)230 static void fatal(const char *x, ...)
231 {
232 va_list ap;
233
234 va_start(ap, x);
235 vfprintf(stderr, x, ap);
236 va_end(ap);
237 exit(EXIT_FAILURE);
238 }
239
checked_open(const char * pathname,int flags)240 static int checked_open(const char *pathname, int flags)
241 {
242 int fd = open(pathname, flags);
243
244 if (fd < 0) {
245 perror(pathname);
246 exit(EXIT_FAILURE);
247 }
248
249 return fd;
250 }
251
252 /*
253 * pagemap/kpageflags routines
254 */
255
do_u64_read(int fd,const char * name,uint64_t * buf,unsigned long index,unsigned long count)256 static unsigned long do_u64_read(int fd, const char *name,
257 uint64_t *buf,
258 unsigned long index,
259 unsigned long count)
260 {
261 long bytes;
262
263 if (index > ULONG_MAX / 8)
264 fatal("index overflow: %lu\n", index);
265
266 bytes = pread(fd, buf, count * 8, (off_t)index * 8);
267 if (bytes < 0) {
268 perror(name);
269 exit(EXIT_FAILURE);
270 }
271 if (bytes % 8)
272 fatal("partial read: %lu bytes\n", bytes);
273
274 return bytes / 8;
275 }
276
kpageflags_read(uint64_t * buf,unsigned long index,unsigned long pages)277 static unsigned long kpageflags_read(uint64_t *buf,
278 unsigned long index,
279 unsigned long pages)
280 {
281 return do_u64_read(kpageflags_fd, opt_kpageflags, buf, index, pages);
282 }
283
kpagecgroup_read(uint64_t * buf,unsigned long index,unsigned long pages)284 static unsigned long kpagecgroup_read(uint64_t *buf,
285 unsigned long index,
286 unsigned long pages)
287 {
288 if (kpagecgroup_fd < 0)
289 return pages;
290
291 return do_u64_read(kpagecgroup_fd, opt_kpageflags, buf, index, pages);
292 }
293
kpagecount_read(uint64_t * buf,unsigned long index,unsigned long pages)294 static unsigned long kpagecount_read(uint64_t *buf,
295 unsigned long index,
296 unsigned long pages)
297 {
298 return kpagecount_fd < 0 ? pages :
299 do_u64_read(kpagecount_fd, PROC_KPAGECOUNT,
300 buf, index, pages);
301 }
302
pagemap_read(uint64_t * buf,unsigned long index,unsigned long pages)303 static unsigned long pagemap_read(uint64_t *buf,
304 unsigned long index,
305 unsigned long pages)
306 {
307 return do_u64_read(pagemap_fd, "/proc/pid/pagemap", buf, index, pages);
308 }
309
pagemap_pfn(uint64_t val)310 static unsigned long pagemap_pfn(uint64_t val)
311 {
312 unsigned long pfn;
313
314 if (val & PM_PRESENT)
315 pfn = PM_PFRAME(val);
316 else
317 pfn = 0;
318
319 return pfn;
320 }
321
pagemap_swap_offset(uint64_t val)322 static unsigned long pagemap_swap_offset(uint64_t val)
323 {
324 return val & PM_SWAP ? PM_SWAP_OFFSET(val) : 0;
325 }
326
327 /*
328 * page flag names
329 */
330
page_flag_name(uint64_t flags)331 static char *page_flag_name(uint64_t flags)
332 {
333 static char buf[65];
334 int present;
335 size_t i, j;
336
337 for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
338 present = (flags >> i) & 1;
339 if (!page_flag_names[i]) {
340 if (present)
341 fatal("unknown flag bit %d\n", i);
342 continue;
343 }
344 buf[j++] = present ? page_flag_names[i][0] : '_';
345 }
346
347 return buf;
348 }
349
page_flag_longname(uint64_t flags)350 static char *page_flag_longname(uint64_t flags)
351 {
352 static char buf[1024];
353 size_t i, n;
354
355 for (i = 0, n = 0; i < ARRAY_SIZE(page_flag_names); i++) {
356 if (!page_flag_names[i])
357 continue;
358 if ((flags >> i) & 1)
359 n += snprintf(buf + n, sizeof(buf) - n, "%s,",
360 page_flag_names[i] + 2);
361 }
362 if (n)
363 n--;
364 buf[n] = '\0';
365
366 return buf;
367 }
368
369
370 /*
371 * page list and summary
372 */
373
show_page_range(unsigned long voffset,unsigned long offset,unsigned long size,uint64_t flags,uint64_t cgroup,uint64_t mapcnt)374 static void show_page_range(unsigned long voffset, unsigned long offset,
375 unsigned long size, uint64_t flags,
376 uint64_t cgroup, uint64_t mapcnt)
377 {
378 static uint64_t flags0;
379 static uint64_t cgroup0;
380 static uint64_t mapcnt0;
381 static unsigned long voff;
382 static unsigned long index;
383 static unsigned long count;
384
385 if (flags == flags0 && cgroup == cgroup0 && mapcnt == mapcnt0 &&
386 offset == index + count && size && voffset == voff + count) {
387 count += size;
388 return;
389 }
390
391 if (count) {
392 if (opt_pid)
393 printf("%lx\t", voff);
394 if (opt_file)
395 printf("%lx\t", voff);
396 if (opt_list_cgroup)
397 printf("@%llu\t", (unsigned long long)cgroup0);
398 if (opt_list_mapcnt)
399 printf("%lu\t", mapcnt0);
400 printf("%lx\t%lx\t%s\n",
401 index, count, page_flag_name(flags0));
402 }
403
404 flags0 = flags;
405 cgroup0 = cgroup;
406 mapcnt0 = mapcnt;
407 index = offset;
408 voff = voffset;
409 count = size;
410 }
411
flush_page_range(void)412 static void flush_page_range(void)
413 {
414 show_page_range(0, 0, 0, 0, 0, 0);
415 }
416
show_page(unsigned long voffset,unsigned long offset,uint64_t flags,uint64_t cgroup,uint64_t mapcnt)417 static void show_page(unsigned long voffset, unsigned long offset,
418 uint64_t flags, uint64_t cgroup, uint64_t mapcnt)
419 {
420 if (opt_pid)
421 printf("%lx\t", voffset);
422 if (opt_file)
423 printf("%lx\t", voffset);
424 if (opt_list_cgroup)
425 printf("@%llu\t", (unsigned long long)cgroup);
426 if (opt_list_mapcnt)
427 printf("%lu\t", mapcnt);
428
429 printf("%lx\t%s\n", offset, page_flag_name(flags));
430 }
431
show_summary(void)432 static void show_summary(void)
433 {
434 size_t i;
435
436 printf(" flags\tpage-count MB"
437 " symbolic-flags\t\t\tlong-symbolic-flags\n");
438
439 for (i = 0; i < ARRAY_SIZE(nr_pages); i++) {
440 if (nr_pages[i])
441 printf("0x%016llx\t%10lu %8lu %s\t%s\n",
442 (unsigned long long)page_flags[i],
443 nr_pages[i],
444 pages2mb(nr_pages[i]),
445 page_flag_name(page_flags[i]),
446 page_flag_longname(page_flags[i]));
447 }
448
449 printf(" total\t%10lu %8lu\n",
450 total_pages, pages2mb(total_pages));
451 }
452
453
454 /*
455 * page flag filters
456 */
457
bit_mask_ok(uint64_t flags)458 static int bit_mask_ok(uint64_t flags)
459 {
460 int i;
461
462 for (i = 0; i < nr_bit_filters; i++) {
463 if (opt_bits[i] == KPF_ALL_BITS) {
464 if ((flags & opt_mask[i]) == 0)
465 return 0;
466 } else {
467 if ((flags & opt_mask[i]) != opt_bits[i])
468 return 0;
469 }
470 }
471
472 return 1;
473 }
474
expand_overloaded_flags(uint64_t flags,uint64_t pme)475 static uint64_t expand_overloaded_flags(uint64_t flags, uint64_t pme)
476 {
477 /* Anonymous pages overload PG_mappedtodisk */
478 if ((flags & BIT(ANON)) && (flags & BIT(MAPPEDTODISK)))
479 flags ^= BIT(MAPPEDTODISK) | BIT(ANON_EXCLUSIVE);
480
481 /* SLOB/SLUB overload several page flags */
482 if (flags & BIT(SLAB)) {
483 if (flags & BIT(PRIVATE))
484 flags ^= BIT(PRIVATE) | BIT(SLOB_FREE);
485 if (flags & BIT(ACTIVE))
486 flags ^= BIT(ACTIVE) | BIT(SLUB_FROZEN);
487 if (flags & BIT(ERROR))
488 flags ^= BIT(ERROR) | BIT(SLUB_DEBUG);
489 }
490
491 /* PG_reclaim is overloaded as PG_readahead in the read path */
492 if ((flags & (BIT(RECLAIM) | BIT(WRITEBACK))) == BIT(RECLAIM))
493 flags ^= BIT(RECLAIM) | BIT(READAHEAD);
494
495 if (pme & PM_SOFT_DIRTY)
496 flags |= BIT(SOFTDIRTY);
497 if (pme & PM_FILE)
498 flags |= BIT(FILE);
499 if (pme & PM_SWAP)
500 flags |= BIT(SWAP);
501 if (pme & PM_MMAP_EXCLUSIVE)
502 flags |= BIT(MMAP_EXCLUSIVE);
503
504 return flags;
505 }
506
well_known_flags(uint64_t flags)507 static uint64_t well_known_flags(uint64_t flags)
508 {
509 /* hide flags intended only for kernel hacker */
510 flags &= ~KPF_HACKERS_BITS;
511
512 /* hide non-hugeTLB compound pages */
513 if ((flags & BITS_COMPOUND) && !(flags & BIT(HUGE)))
514 flags &= ~BITS_COMPOUND;
515
516 return flags;
517 }
518
kpageflags_flags(uint64_t flags,uint64_t pme)519 static uint64_t kpageflags_flags(uint64_t flags, uint64_t pme)
520 {
521 if (opt_raw)
522 flags = expand_overloaded_flags(flags, pme);
523 else
524 flags = well_known_flags(flags);
525
526 return flags;
527 }
528
529 /*
530 * page actions
531 */
532
prepare_hwpoison_fd(void)533 static void prepare_hwpoison_fd(void)
534 {
535 char buf[MAX_PATH + 1];
536
537 hwpoison_debug_fs = debugfs__mount();
538 if (!hwpoison_debug_fs) {
539 perror("mount debugfs");
540 exit(EXIT_FAILURE);
541 }
542
543 if (opt_hwpoison && !hwpoison_inject_fd) {
544 snprintf(buf, MAX_PATH, "%s/hwpoison/corrupt-pfn",
545 hwpoison_debug_fs);
546 hwpoison_inject_fd = checked_open(buf, O_WRONLY);
547 }
548
549 if (opt_unpoison && !hwpoison_forget_fd) {
550 snprintf(buf, MAX_PATH, "%s/hwpoison/unpoison-pfn",
551 hwpoison_debug_fs);
552 hwpoison_forget_fd = checked_open(buf, O_WRONLY);
553 }
554 }
555
hwpoison_page(unsigned long offset)556 static int hwpoison_page(unsigned long offset)
557 {
558 char buf[100];
559 int len;
560
561 len = sprintf(buf, "0x%lx\n", offset);
562 len = write(hwpoison_inject_fd, buf, len);
563 if (len < 0) {
564 perror("hwpoison inject");
565 return len;
566 }
567 return 0;
568 }
569
unpoison_page(unsigned long offset)570 static int unpoison_page(unsigned long offset)
571 {
572 char buf[100];
573 int len;
574
575 len = sprintf(buf, "0x%lx\n", offset);
576 len = write(hwpoison_forget_fd, buf, len);
577 if (len < 0) {
578 perror("hwpoison forget");
579 return len;
580 }
581 return 0;
582 }
583
mark_page_idle(unsigned long offset)584 static int mark_page_idle(unsigned long offset)
585 {
586 static unsigned long off;
587 static uint64_t buf;
588 int len;
589
590 if ((offset / 64 == off / 64) || buf == 0) {
591 buf |= 1UL << (offset % 64);
592 off = offset;
593 return 0;
594 }
595
596 len = pwrite(page_idle_fd, &buf, 8, 8 * (off / 64));
597 if (len < 0) {
598 perror("mark page idle");
599 return len;
600 }
601
602 buf = 1UL << (offset % 64);
603 off = offset;
604
605 return 0;
606 }
607
608 /*
609 * page frame walker
610 */
611
hash_slot(uint64_t flags)612 static size_t hash_slot(uint64_t flags)
613 {
614 size_t k = HASH_KEY(flags);
615 size_t i;
616
617 /* Explicitly reserve slot 0 for flags 0: the following logic
618 * cannot distinguish an unoccupied slot from slot (flags==0).
619 */
620 if (flags == 0)
621 return 0;
622
623 /* search through the remaining (HASH_SIZE-1) slots */
624 for (i = 1; i < ARRAY_SIZE(page_flags); i++, k++) {
625 if (!k || k >= ARRAY_SIZE(page_flags))
626 k = 1;
627 if (page_flags[k] == 0) {
628 page_flags[k] = flags;
629 return k;
630 }
631 if (page_flags[k] == flags)
632 return k;
633 }
634
635 fatal("hash table full: bump up HASH_SHIFT?\n");
636 exit(EXIT_FAILURE);
637 }
638
add_page(unsigned long voffset,unsigned long offset,uint64_t flags,uint64_t cgroup,uint64_t mapcnt,uint64_t pme)639 static void add_page(unsigned long voffset, unsigned long offset,
640 uint64_t flags, uint64_t cgroup, uint64_t mapcnt,
641 uint64_t pme)
642 {
643 flags = kpageflags_flags(flags, pme);
644
645 if (!bit_mask_ok(flags))
646 return;
647
648 if (opt_cgroup && cgroup != (uint64_t)opt_cgroup)
649 return;
650
651 if (opt_hwpoison)
652 hwpoison_page(offset);
653 if (opt_unpoison)
654 unpoison_page(offset);
655
656 if (opt_mark_idle)
657 mark_page_idle(offset);
658
659 if (opt_list == 1)
660 show_page_range(voffset, offset, 1, flags, cgroup, mapcnt);
661 else if (opt_list == 2)
662 show_page(voffset, offset, flags, cgroup, mapcnt);
663
664 nr_pages[hash_slot(flags)]++;
665 total_pages++;
666 }
667
668 #define KPAGEFLAGS_BATCH (64 << 10) /* 64k pages */
walk_pfn(unsigned long voffset,unsigned long index,unsigned long count,uint64_t pme)669 static void walk_pfn(unsigned long voffset,
670 unsigned long index,
671 unsigned long count,
672 uint64_t pme)
673 {
674 uint64_t buf[KPAGEFLAGS_BATCH];
675 uint64_t cgi[KPAGEFLAGS_BATCH];
676 uint64_t cnt[KPAGEFLAGS_BATCH];
677 unsigned long batch;
678 unsigned long pages;
679 unsigned long i;
680
681 /*
682 * kpagecgroup_read() reads only if kpagecgroup were opened, but
683 * /proc/kpagecgroup might even not exist, so it's better to fill
684 * them with zeros here.
685 */
686 if (count == 1)
687 cgi[0] = 0;
688 else
689 memset(cgi, 0, sizeof cgi);
690
691 while (count) {
692 batch = min_t(unsigned long, count, KPAGEFLAGS_BATCH);
693 pages = kpageflags_read(buf, index, batch);
694 if (pages == 0)
695 break;
696
697 if (kpagecgroup_read(cgi, index, pages) != pages)
698 fatal("kpagecgroup returned fewer pages than expected");
699
700 if (kpagecount_read(cnt, index, pages) != pages)
701 fatal("kpagecount returned fewer pages than expected");
702
703 for (i = 0; i < pages; i++)
704 add_page(voffset + i, index + i,
705 buf[i], cgi[i], cnt[i], pme);
706
707 index += pages;
708 count -= pages;
709 }
710 }
711
walk_swap(unsigned long voffset,uint64_t pme)712 static void walk_swap(unsigned long voffset, uint64_t pme)
713 {
714 uint64_t flags = kpageflags_flags(0, pme);
715
716 if (!bit_mask_ok(flags))
717 return;
718
719 if (opt_cgroup)
720 return;
721
722 if (opt_list == 1)
723 show_page_range(voffset, pagemap_swap_offset(pme),
724 1, flags, 0, 0);
725 else if (opt_list == 2)
726 show_page(voffset, pagemap_swap_offset(pme), flags, 0, 0);
727
728 nr_pages[hash_slot(flags)]++;
729 total_pages++;
730 }
731
732 #define PAGEMAP_BATCH (64 << 10)
walk_vma(unsigned long index,unsigned long count)733 static void walk_vma(unsigned long index, unsigned long count)
734 {
735 uint64_t buf[PAGEMAP_BATCH];
736 unsigned long batch;
737 unsigned long pages;
738 unsigned long pfn;
739 unsigned long i;
740
741 while (count) {
742 batch = min_t(unsigned long, count, PAGEMAP_BATCH);
743 pages = pagemap_read(buf, index, batch);
744 if (pages == 0)
745 break;
746
747 for (i = 0; i < pages; i++) {
748 pfn = pagemap_pfn(buf[i]);
749 if (pfn)
750 walk_pfn(index + i, pfn, 1, buf[i]);
751 if (buf[i] & PM_SWAP)
752 walk_swap(index + i, buf[i]);
753 }
754
755 index += pages;
756 count -= pages;
757 }
758 }
759
walk_task(unsigned long index,unsigned long count)760 static void walk_task(unsigned long index, unsigned long count)
761 {
762 const unsigned long end = index + count;
763 unsigned long start;
764 int i = 0;
765
766 while (index < end) {
767
768 while (pg_end[i] <= index)
769 if (++i >= nr_vmas)
770 return;
771 if (pg_start[i] >= end)
772 return;
773
774 start = max_t(unsigned long, pg_start[i], index);
775 index = min_t(unsigned long, pg_end[i], end);
776
777 assert(start < index);
778 walk_vma(start, index - start);
779 }
780 }
781
add_addr_range(unsigned long offset,unsigned long size)782 static void add_addr_range(unsigned long offset, unsigned long size)
783 {
784 if (nr_addr_ranges >= MAX_ADDR_RANGES)
785 fatal("too many addr ranges\n");
786
787 opt_offset[nr_addr_ranges] = offset;
788 opt_size[nr_addr_ranges] = min_t(unsigned long, size, ULONG_MAX-offset);
789 nr_addr_ranges++;
790 }
791
walk_addr_ranges(void)792 static void walk_addr_ranges(void)
793 {
794 int i;
795
796 kpageflags_fd = checked_open(opt_kpageflags, O_RDONLY);
797
798 if (!nr_addr_ranges)
799 add_addr_range(0, ULONG_MAX);
800
801 for (i = 0; i < nr_addr_ranges; i++)
802 if (!opt_pid)
803 walk_pfn(opt_offset[i], opt_offset[i], opt_size[i], 0);
804 else
805 walk_task(opt_offset[i], opt_size[i]);
806
807 if (opt_mark_idle)
808 mark_page_idle(0);
809
810 close(kpageflags_fd);
811 }
812
813
814 /*
815 * user interface
816 */
817
page_flag_type(uint64_t flag)818 static const char *page_flag_type(uint64_t flag)
819 {
820 if (flag & KPF_HACKERS_BITS)
821 return "(r)";
822 if (flag & KPF_OVERLOADED_BITS)
823 return "(o)";
824 return " ";
825 }
826
usage(void)827 static void usage(void)
828 {
829 size_t i, j;
830
831 printf(
832 "page-types [options]\n"
833 " -r|--raw Raw mode, for kernel developers\n"
834 " -d|--describe flags Describe flags\n"
835 " -a|--addr addr-spec Walk a range of pages\n"
836 " -b|--bits bits-spec Walk pages with specified bits\n"
837 " -c|--cgroup path|@inode Walk pages within memory cgroup\n"
838 " -p|--pid pid Walk process address space\n"
839 " -f|--file filename Walk file address space\n"
840 " -i|--mark-idle Mark pages idle\n"
841 " -l|--list Show page details in ranges\n"
842 " -L|--list-each Show page details one by one\n"
843 " -C|--list-cgroup Show cgroup inode for pages\n"
844 " -M|--list-mapcnt Show page map count\n"
845 " -N|--no-summary Don't show summary info\n"
846 " -X|--hwpoison hwpoison pages\n"
847 " -x|--unpoison unpoison pages\n"
848 " -F|--kpageflags filename kpageflags file to parse\n"
849 " -h|--help Show this usage message\n"
850 "flags:\n"
851 " 0x10 bitfield format, e.g.\n"
852 " anon bit-name, e.g.\n"
853 " 0x10,anon comma-separated list, e.g.\n"
854 "addr-spec:\n"
855 " N one page at offset N (unit: pages)\n"
856 " N+M pages range from N to N+M-1\n"
857 " N,M pages range from N to M-1\n"
858 " N, pages range from N to end\n"
859 " ,M pages range from 0 to M-1\n"
860 "bits-spec:\n"
861 " bit1,bit2 (flags & (bit1|bit2)) != 0\n"
862 " bit1,bit2=bit1 (flags & (bit1|bit2)) == bit1\n"
863 " bit1,~bit2 (flags & (bit1|bit2)) == bit1\n"
864 " =bit1,bit2 flags == (bit1|bit2)\n"
865 "bit-names:\n"
866 );
867
868 for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
869 if (!page_flag_names[i])
870 continue;
871 printf("%16s%s", page_flag_names[i] + 2,
872 page_flag_type(1ULL << i));
873 if (++j > 3) {
874 j = 0;
875 putchar('\n');
876 }
877 }
878 printf("\n "
879 "(r) raw mode bits (o) overloaded bits\n");
880 }
881
parse_number(const char * str)882 static unsigned long long parse_number(const char *str)
883 {
884 unsigned long long n;
885
886 n = strtoll(str, NULL, 0);
887
888 if (n == 0 && str[0] != '0')
889 fatal("invalid name or number: %s\n", str);
890
891 return n;
892 }
893
parse_pid(const char * str)894 static void parse_pid(const char *str)
895 {
896 FILE *file;
897 char buf[5000];
898
899 opt_pid = parse_number(str);
900
901 sprintf(buf, "/proc/%d/pagemap", opt_pid);
902 pagemap_fd = checked_open(buf, O_RDONLY);
903
904 sprintf(buf, "/proc/%d/maps", opt_pid);
905 file = fopen(buf, "r");
906 if (!file) {
907 perror(buf);
908 exit(EXIT_FAILURE);
909 }
910
911 while (fgets(buf, sizeof(buf), file) != NULL) {
912 unsigned long vm_start;
913 unsigned long vm_end;
914 unsigned long long pgoff;
915 int major, minor;
916 char r, w, x, s;
917 unsigned long ino;
918 int n;
919
920 n = sscanf(buf, "%lx-%lx %c%c%c%c %llx %x:%x %lu",
921 &vm_start,
922 &vm_end,
923 &r, &w, &x, &s,
924 &pgoff,
925 &major, &minor,
926 &ino);
927 if (n < 10) {
928 fprintf(stderr, "unexpected line: %s\n", buf);
929 continue;
930 }
931 pg_start[nr_vmas] = vm_start / page_size;
932 pg_end[nr_vmas] = vm_end / page_size;
933 if (++nr_vmas >= MAX_VMAS) {
934 fprintf(stderr, "too many VMAs\n");
935 break;
936 }
937 }
938 fclose(file);
939 }
940
show_file(const char * name,const struct stat * st)941 static void show_file(const char *name, const struct stat *st)
942 {
943 unsigned long long size = st->st_size;
944 char atime[64], mtime[64];
945 long now = time(NULL);
946
947 printf("%s\tInode: %u\tSize: %llu (%llu pages)\n",
948 name, (unsigned)st->st_ino,
949 size, (size + page_size - 1) / page_size);
950
951 strftime(atime, sizeof(atime), "%c", localtime(&st->st_atime));
952 strftime(mtime, sizeof(mtime), "%c", localtime(&st->st_mtime));
953
954 printf("Modify: %s (%ld seconds ago)\nAccess: %s (%ld seconds ago)\n",
955 mtime, now - st->st_mtime,
956 atime, now - st->st_atime);
957 }
958
959 static sigjmp_buf sigbus_jmp;
960
961 static void * volatile sigbus_addr;
962
sigbus_handler(int sig,siginfo_t * info,void * ucontex)963 static void sigbus_handler(int sig, siginfo_t *info, void *ucontex)
964 {
965 (void)sig;
966 (void)ucontex;
967 sigbus_addr = info ? info->si_addr : NULL;
968 siglongjmp(sigbus_jmp, 1);
969 }
970
971 static struct sigaction sigbus_action = {
972 .sa_sigaction = sigbus_handler,
973 .sa_flags = SA_SIGINFO,
974 };
975
walk_file_range(const char * name,int fd,unsigned long off,unsigned long end)976 static void walk_file_range(const char *name, int fd,
977 unsigned long off, unsigned long end)
978 {
979 uint8_t vec[PAGEMAP_BATCH];
980 uint64_t buf[PAGEMAP_BATCH], flags;
981 uint64_t cgroup = 0;
982 uint64_t mapcnt = 0;
983 unsigned long nr_pages, pfn, i;
984 ssize_t len;
985 void *ptr;
986 int first = 1;
987
988 for (; off < end; off += len) {
989 nr_pages = (end - off + page_size - 1) / page_size;
990 if (nr_pages > PAGEMAP_BATCH)
991 nr_pages = PAGEMAP_BATCH;
992 len = nr_pages * page_size;
993
994 ptr = mmap(NULL, len, PROT_READ, MAP_SHARED, fd, off);
995 if (ptr == MAP_FAILED)
996 fatal("mmap failed: %s", name);
997
998 /* determine cached pages */
999 if (mincore(ptr, len, vec))
1000 fatal("mincore failed: %s", name);
1001
1002 /* turn off readahead */
1003 if (madvise(ptr, len, MADV_RANDOM))
1004 fatal("madvice failed: %s", name);
1005
1006 if (sigsetjmp(sigbus_jmp, 1)) {
1007 end = off + sigbus_addr ? sigbus_addr - ptr : 0;
1008 fprintf(stderr, "got sigbus at offset %lld: %s\n",
1009 (long long)end, name);
1010 goto got_sigbus;
1011 }
1012
1013 /* populate ptes */
1014 for (i = 0; i < nr_pages ; i++) {
1015 if (vec[i] & 1)
1016 (void)*(volatile int *)(ptr + i * page_size);
1017 }
1018 got_sigbus:
1019
1020 /* turn off harvesting reference bits */
1021 if (madvise(ptr, len, MADV_SEQUENTIAL))
1022 fatal("madvice failed: %s", name);
1023
1024 if (pagemap_read(buf, (unsigned long)ptr / page_size,
1025 nr_pages) != nr_pages)
1026 fatal("cannot read pagemap");
1027
1028 munmap(ptr, len);
1029
1030 for (i = 0; i < nr_pages; i++) {
1031 pfn = pagemap_pfn(buf[i]);
1032 if (!pfn)
1033 continue;
1034 if (!kpageflags_read(&flags, pfn, 1))
1035 continue;
1036 if (!kpagecgroup_read(&cgroup, pfn, 1))
1037 fatal("kpagecgroup_read failed");
1038 if (!kpagecount_read(&mapcnt, pfn, 1))
1039 fatal("kpagecount_read failed");
1040 if (first && opt_list) {
1041 first = 0;
1042 flush_page_range();
1043 }
1044 add_page(off / page_size + i, pfn,
1045 flags, cgroup, mapcnt, buf[i]);
1046 }
1047 }
1048 }
1049
walk_file(const char * name,const struct stat * st)1050 static void walk_file(const char *name, const struct stat *st)
1051 {
1052 int i;
1053 int fd;
1054
1055 fd = checked_open(name, O_RDONLY|O_NOATIME|O_NOFOLLOW);
1056
1057 if (!nr_addr_ranges)
1058 add_addr_range(0, st->st_size / page_size);
1059
1060 for (i = 0; i < nr_addr_ranges; i++)
1061 walk_file_range(name, fd, opt_offset[i] * page_size,
1062 (opt_offset[i] + opt_size[i]) * page_size);
1063
1064 close(fd);
1065 }
1066
walk_tree(const char * name,const struct stat * st,int type,struct FTW * f)1067 int walk_tree(const char *name, const struct stat *st, int type, struct FTW *f)
1068 {
1069 (void)f;
1070 switch (type) {
1071 case FTW_F:
1072 if (S_ISREG(st->st_mode))
1073 walk_file(name, st);
1074 break;
1075 case FTW_DNR:
1076 fprintf(stderr, "cannot read dir: %s\n", name);
1077 break;
1078 }
1079 return 0;
1080 }
1081
1082 struct stat st;
1083
walk_page_cache(void)1084 static void walk_page_cache(void)
1085 {
1086 kpageflags_fd = checked_open(opt_kpageflags, O_RDONLY);
1087 pagemap_fd = checked_open("/proc/self/pagemap", O_RDONLY);
1088 sigaction(SIGBUS, &sigbus_action, NULL);
1089
1090 if (stat(opt_file, &st))
1091 fatal("stat failed: %s\n", opt_file);
1092
1093 if (S_ISREG(st.st_mode)) {
1094 walk_file(opt_file, &st);
1095 } else if (S_ISDIR(st.st_mode)) {
1096 /* do not follow symlinks and mountpoints */
1097 if (nftw(opt_file, walk_tree, 64, FTW_MOUNT | FTW_PHYS) < 0)
1098 fatal("nftw failed: %s\n", opt_file);
1099 } else
1100 fatal("unhandled file type: %s\n", opt_file);
1101
1102 close(kpageflags_fd);
1103 close(pagemap_fd);
1104 signal(SIGBUS, SIG_DFL);
1105 }
1106
parse_file(const char * name)1107 static void parse_file(const char *name)
1108 {
1109 opt_file = name;
1110 }
1111
parse_cgroup(const char * path)1112 static void parse_cgroup(const char *path)
1113 {
1114 if (path[0] == '@') {
1115 opt_cgroup = parse_number(path + 1);
1116 return;
1117 }
1118
1119 struct stat st;
1120
1121 if (stat(path, &st))
1122 fatal("stat failed: %s: %m\n", path);
1123
1124 if (!S_ISDIR(st.st_mode))
1125 fatal("cgroup supposed to be a directory: %s\n", path);
1126
1127 opt_cgroup = st.st_ino;
1128 }
1129
parse_addr_range(const char * optarg)1130 static void parse_addr_range(const char *optarg)
1131 {
1132 unsigned long offset;
1133 unsigned long size;
1134 char *p;
1135
1136 p = strchr(optarg, ',');
1137 if (!p)
1138 p = strchr(optarg, '+');
1139
1140 if (p == optarg) {
1141 offset = 0;
1142 size = parse_number(p + 1);
1143 } else if (p) {
1144 offset = parse_number(optarg);
1145 if (p[1] == '\0')
1146 size = ULONG_MAX;
1147 else {
1148 size = parse_number(p + 1);
1149 if (*p == ',') {
1150 if (size < offset)
1151 fatal("invalid range: %lu,%lu\n",
1152 offset, size);
1153 size -= offset;
1154 }
1155 }
1156 } else {
1157 offset = parse_number(optarg);
1158 size = 1;
1159 }
1160
1161 add_addr_range(offset, size);
1162 }
1163
add_bits_filter(uint64_t mask,uint64_t bits)1164 static void add_bits_filter(uint64_t mask, uint64_t bits)
1165 {
1166 if (nr_bit_filters >= MAX_BIT_FILTERS)
1167 fatal("too much bit filters\n");
1168
1169 opt_mask[nr_bit_filters] = mask;
1170 opt_bits[nr_bit_filters] = bits;
1171 nr_bit_filters++;
1172 }
1173
parse_flag_name(const char * str,int len)1174 static uint64_t parse_flag_name(const char *str, int len)
1175 {
1176 size_t i;
1177
1178 if (!*str || !len)
1179 return 0;
1180
1181 if (len <= 8 && !strncmp(str, "compound", len))
1182 return BITS_COMPOUND;
1183
1184 for (i = 0; i < ARRAY_SIZE(page_flag_names); i++) {
1185 if (!page_flag_names[i])
1186 continue;
1187 if (!strncmp(str, page_flag_names[i] + 2, len))
1188 return 1ULL << i;
1189 }
1190
1191 return parse_number(str);
1192 }
1193
parse_flag_names(const char * str,int all)1194 static uint64_t parse_flag_names(const char *str, int all)
1195 {
1196 const char *p = str;
1197 uint64_t flags = 0;
1198
1199 while (1) {
1200 if (*p == ',' || *p == '=' || *p == '\0') {
1201 if ((*str != '~') || (*str == '~' && all && *++str))
1202 flags |= parse_flag_name(str, p - str);
1203 if (*p != ',')
1204 break;
1205 str = p + 1;
1206 }
1207 p++;
1208 }
1209
1210 return flags;
1211 }
1212
parse_bits_mask(const char * optarg)1213 static void parse_bits_mask(const char *optarg)
1214 {
1215 uint64_t mask;
1216 uint64_t bits;
1217 const char *p;
1218
1219 p = strchr(optarg, '=');
1220 if (p == optarg) {
1221 mask = KPF_ALL_BITS;
1222 bits = parse_flag_names(p + 1, 0);
1223 } else if (p) {
1224 mask = parse_flag_names(optarg, 0);
1225 bits = parse_flag_names(p + 1, 0);
1226 } else if (strchr(optarg, '~')) {
1227 mask = parse_flag_names(optarg, 1);
1228 bits = parse_flag_names(optarg, 0);
1229 } else {
1230 mask = parse_flag_names(optarg, 0);
1231 bits = KPF_ALL_BITS;
1232 }
1233
1234 add_bits_filter(mask, bits);
1235 }
1236
parse_kpageflags(const char * name)1237 static void parse_kpageflags(const char *name)
1238 {
1239 opt_kpageflags = name;
1240 }
1241
describe_flags(const char * optarg)1242 static void describe_flags(const char *optarg)
1243 {
1244 uint64_t flags = parse_flag_names(optarg, 0);
1245
1246 printf("0x%016llx\t%s\t%s\n",
1247 (unsigned long long)flags,
1248 page_flag_name(flags),
1249 page_flag_longname(flags));
1250 }
1251
1252 static const struct option opts[] = {
1253 { "raw" , 0, NULL, 'r' },
1254 { "pid" , 1, NULL, 'p' },
1255 { "file" , 1, NULL, 'f' },
1256 { "addr" , 1, NULL, 'a' },
1257 { "bits" , 1, NULL, 'b' },
1258 { "cgroup" , 1, NULL, 'c' },
1259 { "describe" , 1, NULL, 'd' },
1260 { "mark-idle" , 0, NULL, 'i' },
1261 { "list" , 0, NULL, 'l' },
1262 { "list-each" , 0, NULL, 'L' },
1263 { "list-cgroup", 0, NULL, 'C' },
1264 { "list-mapcnt", 0, NULL, 'M' },
1265 { "no-summary", 0, NULL, 'N' },
1266 { "hwpoison" , 0, NULL, 'X' },
1267 { "unpoison" , 0, NULL, 'x' },
1268 { "kpageflags", 0, NULL, 'F' },
1269 { "help" , 0, NULL, 'h' },
1270 { NULL , 0, NULL, 0 }
1271 };
1272
main(int argc,char * argv[])1273 int main(int argc, char *argv[])
1274 {
1275 int c;
1276
1277 page_size = getpagesize();
1278
1279 while ((c = getopt_long(argc, argv,
1280 "rp:f:a:b:d:c:CilLMNXxF:h",
1281 opts, NULL)) != -1) {
1282 switch (c) {
1283 case 'r':
1284 opt_raw = 1;
1285 break;
1286 case 'p':
1287 parse_pid(optarg);
1288 break;
1289 case 'f':
1290 parse_file(optarg);
1291 break;
1292 case 'a':
1293 parse_addr_range(optarg);
1294 break;
1295 case 'b':
1296 parse_bits_mask(optarg);
1297 break;
1298 case 'c':
1299 parse_cgroup(optarg);
1300 break;
1301 case 'C':
1302 opt_list_cgroup = 1;
1303 break;
1304 case 'd':
1305 describe_flags(optarg);
1306 exit(0);
1307 case 'i':
1308 opt_mark_idle = 1;
1309 break;
1310 case 'l':
1311 opt_list = 1;
1312 break;
1313 case 'L':
1314 opt_list = 2;
1315 break;
1316 case 'M':
1317 opt_list_mapcnt = 1;
1318 break;
1319 case 'N':
1320 opt_no_summary = 1;
1321 break;
1322 case 'X':
1323 opt_hwpoison = 1;
1324 prepare_hwpoison_fd();
1325 break;
1326 case 'x':
1327 opt_unpoison = 1;
1328 prepare_hwpoison_fd();
1329 break;
1330 case 'F':
1331 parse_kpageflags(optarg);
1332 break;
1333 case 'h':
1334 usage();
1335 exit(0);
1336 default:
1337 usage();
1338 exit(1);
1339 }
1340 }
1341
1342 if (!opt_kpageflags)
1343 opt_kpageflags = PROC_KPAGEFLAGS;
1344
1345 if (opt_cgroup || opt_list_cgroup)
1346 kpagecgroup_fd = checked_open(PROC_KPAGECGROUP, O_RDONLY);
1347
1348 if (opt_list && opt_list_mapcnt)
1349 kpagecount_fd = checked_open(PROC_KPAGECOUNT, O_RDONLY);
1350
1351 if (opt_mark_idle)
1352 page_idle_fd = checked_open(SYS_KERNEL_MM_PAGE_IDLE, O_RDWR);
1353
1354 if (opt_list && opt_pid)
1355 printf("voffset\t");
1356 if (opt_list && opt_file)
1357 printf("foffset\t");
1358 if (opt_list && opt_list_cgroup)
1359 printf("cgroup\t");
1360 if (opt_list && opt_list_mapcnt)
1361 printf("map-cnt\t");
1362
1363 if (opt_list == 1)
1364 printf("offset\tlen\tflags\n");
1365 if (opt_list == 2)
1366 printf("offset\tflags\n");
1367
1368 if (opt_file)
1369 walk_page_cache();
1370 else
1371 walk_addr_ranges();
1372
1373 if (opt_list == 1)
1374 flush_page_range();
1375
1376 if (opt_no_summary)
1377 return 0;
1378
1379 if (opt_list)
1380 printf("\n\n");
1381
1382 if (opt_file) {
1383 show_file(opt_file, &st);
1384 printf("\n");
1385 }
1386
1387 show_summary();
1388
1389 if (opt_list_mapcnt)
1390 close(kpagecount_fd);
1391
1392 if (page_idle_fd >= 0)
1393 close(page_idle_fd);
1394
1395 return 0;
1396 }
1397