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
82 /* [48-] take some arbitrary free slots for expanding overloaded flags
83 * not part of kernel API
84 */
85 #define KPF_READAHEAD 48
86 #define KPF_SLOB_FREE 49
87 #define KPF_SLUB_FROZEN 50
88 #define KPF_SLUB_DEBUG 51
89 #define KPF_FILE 61
90 #define KPF_SWAP 62
91 #define KPF_MMAP_EXCLUSIVE 63
92
93 #define KPF_ALL_BITS ((uint64_t)~0ULL)
94 #define KPF_HACKERS_BITS (0xffffULL << 32)
95 #define KPF_OVERLOADED_BITS (0xffffULL << 48)
96 #define BIT(name) (1ULL << KPF_##name)
97 #define BITS_COMPOUND (BIT(COMPOUND_HEAD) | BIT(COMPOUND_TAIL))
98
99 static const char * const page_flag_names[] = {
100 [KPF_LOCKED] = "L:locked",
101 [KPF_ERROR] = "E:error",
102 [KPF_REFERENCED] = "R:referenced",
103 [KPF_UPTODATE] = "U:uptodate",
104 [KPF_DIRTY] = "D:dirty",
105 [KPF_LRU] = "l:lru",
106 [KPF_ACTIVE] = "A:active",
107 [KPF_SLAB] = "S:slab",
108 [KPF_WRITEBACK] = "W:writeback",
109 [KPF_RECLAIM] = "I:reclaim",
110 [KPF_BUDDY] = "B:buddy",
111
112 [KPF_MMAP] = "M:mmap",
113 [KPF_ANON] = "a:anonymous",
114 [KPF_SWAPCACHE] = "s:swapcache",
115 [KPF_SWAPBACKED] = "b:swapbacked",
116 [KPF_COMPOUND_HEAD] = "H:compound_head",
117 [KPF_COMPOUND_TAIL] = "T:compound_tail",
118 [KPF_HUGE] = "G:huge",
119 [KPF_UNEVICTABLE] = "u:unevictable",
120 [KPF_HWPOISON] = "X:hwpoison",
121 [KPF_NOPAGE] = "n:nopage",
122 [KPF_KSM] = "x:ksm",
123 [KPF_THP] = "t:thp",
124 [KPF_OFFLINE] = "o:offline",
125 [KPF_PGTABLE] = "g:pgtable",
126 [KPF_ZERO_PAGE] = "z:zero_page",
127 [KPF_IDLE] = "i:idle_page",
128
129 [KPF_RESERVED] = "r:reserved",
130 [KPF_MLOCKED] = "m:mlocked",
131 [KPF_MAPPEDTODISK] = "d:mappedtodisk",
132 [KPF_PRIVATE] = "P:private",
133 [KPF_PRIVATE_2] = "p:private_2",
134 [KPF_OWNER_PRIVATE] = "O:owner_private",
135 [KPF_ARCH] = "h:arch",
136 [KPF_UNCACHED] = "c:uncached",
137 [KPF_SOFTDIRTY] = "f:softdirty",
138
139 [KPF_READAHEAD] = "I:readahead",
140 [KPF_SLOB_FREE] = "P:slob_free",
141 [KPF_SLUB_FROZEN] = "A:slub_frozen",
142 [KPF_SLUB_DEBUG] = "E:slub_debug",
143
144 [KPF_FILE] = "F:file",
145 [KPF_SWAP] = "w:swap",
146 [KPF_MMAP_EXCLUSIVE] = "1:mmap_exclusive",
147 };
148
149
150 /*
151 * data structures
152 */
153
154 static int opt_raw; /* for kernel developers */
155 static int opt_list; /* list pages (in ranges) */
156 static int opt_mark_idle; /* set accessed bit */
157 static int opt_no_summary; /* don't show summary */
158 static pid_t opt_pid; /* process to walk */
159 const char *opt_file; /* file or directory path */
160 static uint64_t opt_cgroup; /* cgroup inode */
161 static int opt_list_cgroup;/* list page cgroup */
162 static int opt_list_mapcnt;/* list page map count */
163 static const char *opt_kpageflags;/* kpageflags file to parse */
164
165 #define MAX_ADDR_RANGES 1024
166 static int nr_addr_ranges;
167 static unsigned long opt_offset[MAX_ADDR_RANGES];
168 static unsigned long opt_size[MAX_ADDR_RANGES];
169
170 #define MAX_VMAS 10240
171 static int nr_vmas;
172 static unsigned long pg_start[MAX_VMAS];
173 static unsigned long pg_end[MAX_VMAS];
174
175 #define MAX_BIT_FILTERS 64
176 static int nr_bit_filters;
177 static uint64_t opt_mask[MAX_BIT_FILTERS];
178 static uint64_t opt_bits[MAX_BIT_FILTERS];
179
180 static int page_size;
181
182 static int pagemap_fd;
183 static int kpageflags_fd;
184 static int kpagecount_fd = -1;
185 static int kpagecgroup_fd = -1;
186 static int page_idle_fd = -1;
187
188 static int opt_hwpoison;
189 static int opt_unpoison;
190
191 static const char *hwpoison_debug_fs;
192 static int hwpoison_inject_fd;
193 static int hwpoison_forget_fd;
194
195 #define HASH_SHIFT 13
196 #define HASH_SIZE (1 << HASH_SHIFT)
197 #define HASH_MASK (HASH_SIZE - 1)
198 #define HASH_KEY(flags) (flags & HASH_MASK)
199
200 static unsigned long total_pages;
201 static unsigned long nr_pages[HASH_SIZE];
202 static uint64_t page_flags[HASH_SIZE];
203
204
205 /*
206 * helper functions
207 */
208
209 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
210
211 #define min_t(type, x, y) ({ \
212 type __min1 = (x); \
213 type __min2 = (y); \
214 __min1 < __min2 ? __min1 : __min2; })
215
216 #define max_t(type, x, y) ({ \
217 type __max1 = (x); \
218 type __max2 = (y); \
219 __max1 > __max2 ? __max1 : __max2; })
220
pages2mb(unsigned long pages)221 static unsigned long pages2mb(unsigned long pages)
222 {
223 return (pages * page_size) >> 20;
224 }
225
fatal(const char * x,...)226 static void fatal(const char *x, ...)
227 {
228 va_list ap;
229
230 va_start(ap, x);
231 vfprintf(stderr, x, ap);
232 va_end(ap);
233 exit(EXIT_FAILURE);
234 }
235
checked_open(const char * pathname,int flags)236 static int checked_open(const char *pathname, int flags)
237 {
238 int fd = open(pathname, flags);
239
240 if (fd < 0) {
241 perror(pathname);
242 exit(EXIT_FAILURE);
243 }
244
245 return fd;
246 }
247
248 /*
249 * pagemap/kpageflags routines
250 */
251
do_u64_read(int fd,const char * name,uint64_t * buf,unsigned long index,unsigned long count)252 static unsigned long do_u64_read(int fd, const char *name,
253 uint64_t *buf,
254 unsigned long index,
255 unsigned long count)
256 {
257 long bytes;
258
259 if (index > ULONG_MAX / 8)
260 fatal("index overflow: %lu\n", index);
261
262 bytes = pread(fd, buf, count * 8, (off_t)index * 8);
263 if (bytes < 0) {
264 perror(name);
265 exit(EXIT_FAILURE);
266 }
267 if (bytes % 8)
268 fatal("partial read: %lu bytes\n", bytes);
269
270 return bytes / 8;
271 }
272
kpageflags_read(uint64_t * buf,unsigned long index,unsigned long pages)273 static unsigned long kpageflags_read(uint64_t *buf,
274 unsigned long index,
275 unsigned long pages)
276 {
277 return do_u64_read(kpageflags_fd, opt_kpageflags, buf, index, pages);
278 }
279
kpagecgroup_read(uint64_t * buf,unsigned long index,unsigned long pages)280 static unsigned long kpagecgroup_read(uint64_t *buf,
281 unsigned long index,
282 unsigned long pages)
283 {
284 if (kpagecgroup_fd < 0)
285 return pages;
286
287 return do_u64_read(kpagecgroup_fd, opt_kpageflags, buf, index, pages);
288 }
289
kpagecount_read(uint64_t * buf,unsigned long index,unsigned long pages)290 static unsigned long kpagecount_read(uint64_t *buf,
291 unsigned long index,
292 unsigned long pages)
293 {
294 return kpagecount_fd < 0 ? pages :
295 do_u64_read(kpagecount_fd, PROC_KPAGECOUNT,
296 buf, index, pages);
297 }
298
pagemap_read(uint64_t * buf,unsigned long index,unsigned long pages)299 static unsigned long pagemap_read(uint64_t *buf,
300 unsigned long index,
301 unsigned long pages)
302 {
303 return do_u64_read(pagemap_fd, "/proc/pid/pagemap", buf, index, pages);
304 }
305
pagemap_pfn(uint64_t val)306 static unsigned long pagemap_pfn(uint64_t val)
307 {
308 unsigned long pfn;
309
310 if (val & PM_PRESENT)
311 pfn = PM_PFRAME(val);
312 else
313 pfn = 0;
314
315 return pfn;
316 }
317
pagemap_swap_offset(uint64_t val)318 static unsigned long pagemap_swap_offset(uint64_t val)
319 {
320 return val & PM_SWAP ? PM_SWAP_OFFSET(val) : 0;
321 }
322
323 /*
324 * page flag names
325 */
326
page_flag_name(uint64_t flags)327 static char *page_flag_name(uint64_t flags)
328 {
329 static char buf[65];
330 int present;
331 size_t i, j;
332
333 for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
334 present = (flags >> i) & 1;
335 if (!page_flag_names[i]) {
336 if (present)
337 fatal("unknown flag bit %d\n", i);
338 continue;
339 }
340 buf[j++] = present ? page_flag_names[i][0] : '_';
341 }
342
343 return buf;
344 }
345
page_flag_longname(uint64_t flags)346 static char *page_flag_longname(uint64_t flags)
347 {
348 static char buf[1024];
349 size_t i, n;
350
351 for (i = 0, n = 0; i < ARRAY_SIZE(page_flag_names); i++) {
352 if (!page_flag_names[i])
353 continue;
354 if ((flags >> i) & 1)
355 n += snprintf(buf + n, sizeof(buf) - n, "%s,",
356 page_flag_names[i] + 2);
357 }
358 if (n)
359 n--;
360 buf[n] = '\0';
361
362 return buf;
363 }
364
365
366 /*
367 * page list and summary
368 */
369
show_page_range(unsigned long voffset,unsigned long offset,unsigned long size,uint64_t flags,uint64_t cgroup,uint64_t mapcnt)370 static void show_page_range(unsigned long voffset, unsigned long offset,
371 unsigned long size, uint64_t flags,
372 uint64_t cgroup, uint64_t mapcnt)
373 {
374 static uint64_t flags0;
375 static uint64_t cgroup0;
376 static uint64_t mapcnt0;
377 static unsigned long voff;
378 static unsigned long index;
379 static unsigned long count;
380
381 if (flags == flags0 && cgroup == cgroup0 && mapcnt == mapcnt0 &&
382 offset == index + count && size && voffset == voff + count) {
383 count += size;
384 return;
385 }
386
387 if (count) {
388 if (opt_pid)
389 printf("%lx\t", voff);
390 if (opt_file)
391 printf("%lu\t", voff);
392 if (opt_list_cgroup)
393 printf("@%llu\t", (unsigned long long)cgroup0);
394 if (opt_list_mapcnt)
395 printf("%lu\t", mapcnt0);
396 printf("%lx\t%lx\t%s\n",
397 index, count, page_flag_name(flags0));
398 }
399
400 flags0 = flags;
401 cgroup0 = cgroup;
402 mapcnt0 = mapcnt;
403 index = offset;
404 voff = voffset;
405 count = size;
406 }
407
flush_page_range(void)408 static void flush_page_range(void)
409 {
410 show_page_range(0, 0, 0, 0, 0, 0);
411 }
412
show_page(unsigned long voffset,unsigned long offset,uint64_t flags,uint64_t cgroup,uint64_t mapcnt)413 static void show_page(unsigned long voffset, unsigned long offset,
414 uint64_t flags, uint64_t cgroup, uint64_t mapcnt)
415 {
416 if (opt_pid)
417 printf("%lx\t", voffset);
418 if (opt_file)
419 printf("%lu\t", voffset);
420 if (opt_list_cgroup)
421 printf("@%llu\t", (unsigned long long)cgroup);
422 if (opt_list_mapcnt)
423 printf("%lu\t", mapcnt);
424
425 printf("%lx\t%s\n", offset, page_flag_name(flags));
426 }
427
show_summary(void)428 static void show_summary(void)
429 {
430 size_t i;
431
432 printf(" flags\tpage-count MB"
433 " symbolic-flags\t\t\tlong-symbolic-flags\n");
434
435 for (i = 0; i < ARRAY_SIZE(nr_pages); i++) {
436 if (nr_pages[i])
437 printf("0x%016llx\t%10lu %8lu %s\t%s\n",
438 (unsigned long long)page_flags[i],
439 nr_pages[i],
440 pages2mb(nr_pages[i]),
441 page_flag_name(page_flags[i]),
442 page_flag_longname(page_flags[i]));
443 }
444
445 printf(" total\t%10lu %8lu\n",
446 total_pages, pages2mb(total_pages));
447 }
448
449
450 /*
451 * page flag filters
452 */
453
bit_mask_ok(uint64_t flags)454 static int bit_mask_ok(uint64_t flags)
455 {
456 int i;
457
458 for (i = 0; i < nr_bit_filters; i++) {
459 if (opt_bits[i] == KPF_ALL_BITS) {
460 if ((flags & opt_mask[i]) == 0)
461 return 0;
462 } else {
463 if ((flags & opt_mask[i]) != opt_bits[i])
464 return 0;
465 }
466 }
467
468 return 1;
469 }
470
expand_overloaded_flags(uint64_t flags,uint64_t pme)471 static uint64_t expand_overloaded_flags(uint64_t flags, uint64_t pme)
472 {
473 /* SLOB/SLUB overload several page flags */
474 if (flags & BIT(SLAB)) {
475 if (flags & BIT(PRIVATE))
476 flags ^= BIT(PRIVATE) | BIT(SLOB_FREE);
477 if (flags & BIT(ACTIVE))
478 flags ^= BIT(ACTIVE) | BIT(SLUB_FROZEN);
479 if (flags & BIT(ERROR))
480 flags ^= BIT(ERROR) | BIT(SLUB_DEBUG);
481 }
482
483 /* PG_reclaim is overloaded as PG_readahead in the read path */
484 if ((flags & (BIT(RECLAIM) | BIT(WRITEBACK))) == BIT(RECLAIM))
485 flags ^= BIT(RECLAIM) | BIT(READAHEAD);
486
487 if (pme & PM_SOFT_DIRTY)
488 flags |= BIT(SOFTDIRTY);
489 if (pme & PM_FILE)
490 flags |= BIT(FILE);
491 if (pme & PM_SWAP)
492 flags |= BIT(SWAP);
493 if (pme & PM_MMAP_EXCLUSIVE)
494 flags |= BIT(MMAP_EXCLUSIVE);
495
496 return flags;
497 }
498
well_known_flags(uint64_t flags)499 static uint64_t well_known_flags(uint64_t flags)
500 {
501 /* hide flags intended only for kernel hacker */
502 flags &= ~KPF_HACKERS_BITS;
503
504 /* hide non-hugeTLB compound pages */
505 if ((flags & BITS_COMPOUND) && !(flags & BIT(HUGE)))
506 flags &= ~BITS_COMPOUND;
507
508 return flags;
509 }
510
kpageflags_flags(uint64_t flags,uint64_t pme)511 static uint64_t kpageflags_flags(uint64_t flags, uint64_t pme)
512 {
513 if (opt_raw)
514 flags = expand_overloaded_flags(flags, pme);
515 else
516 flags = well_known_flags(flags);
517
518 return flags;
519 }
520
521 /*
522 * page actions
523 */
524
prepare_hwpoison_fd(void)525 static void prepare_hwpoison_fd(void)
526 {
527 char buf[MAX_PATH + 1];
528
529 hwpoison_debug_fs = debugfs__mount();
530 if (!hwpoison_debug_fs) {
531 perror("mount debugfs");
532 exit(EXIT_FAILURE);
533 }
534
535 if (opt_hwpoison && !hwpoison_inject_fd) {
536 snprintf(buf, MAX_PATH, "%s/hwpoison/corrupt-pfn",
537 hwpoison_debug_fs);
538 hwpoison_inject_fd = checked_open(buf, O_WRONLY);
539 }
540
541 if (opt_unpoison && !hwpoison_forget_fd) {
542 snprintf(buf, MAX_PATH, "%s/hwpoison/unpoison-pfn",
543 hwpoison_debug_fs);
544 hwpoison_forget_fd = checked_open(buf, O_WRONLY);
545 }
546 }
547
hwpoison_page(unsigned long offset)548 static int hwpoison_page(unsigned long offset)
549 {
550 char buf[100];
551 int len;
552
553 len = sprintf(buf, "0x%lx\n", offset);
554 len = write(hwpoison_inject_fd, buf, len);
555 if (len < 0) {
556 perror("hwpoison inject");
557 return len;
558 }
559 return 0;
560 }
561
unpoison_page(unsigned long offset)562 static int unpoison_page(unsigned long offset)
563 {
564 char buf[100];
565 int len;
566
567 len = sprintf(buf, "0x%lx\n", offset);
568 len = write(hwpoison_forget_fd, buf, len);
569 if (len < 0) {
570 perror("hwpoison forget");
571 return len;
572 }
573 return 0;
574 }
575
mark_page_idle(unsigned long offset)576 static int mark_page_idle(unsigned long offset)
577 {
578 static unsigned long off;
579 static uint64_t buf;
580 int len;
581
582 if ((offset / 64 == off / 64) || buf == 0) {
583 buf |= 1UL << (offset % 64);
584 off = offset;
585 return 0;
586 }
587
588 len = pwrite(page_idle_fd, &buf, 8, 8 * (off / 64));
589 if (len < 0) {
590 perror("mark page idle");
591 return len;
592 }
593
594 buf = 1UL << (offset % 64);
595 off = offset;
596
597 return 0;
598 }
599
600 /*
601 * page frame walker
602 */
603
hash_slot(uint64_t flags)604 static size_t hash_slot(uint64_t flags)
605 {
606 size_t k = HASH_KEY(flags);
607 size_t i;
608
609 /* Explicitly reserve slot 0 for flags 0: the following logic
610 * cannot distinguish an unoccupied slot from slot (flags==0).
611 */
612 if (flags == 0)
613 return 0;
614
615 /* search through the remaining (HASH_SIZE-1) slots */
616 for (i = 1; i < ARRAY_SIZE(page_flags); i++, k++) {
617 if (!k || k >= ARRAY_SIZE(page_flags))
618 k = 1;
619 if (page_flags[k] == 0) {
620 page_flags[k] = flags;
621 return k;
622 }
623 if (page_flags[k] == flags)
624 return k;
625 }
626
627 fatal("hash table full: bump up HASH_SHIFT?\n");
628 exit(EXIT_FAILURE);
629 }
630
add_page(unsigned long voffset,unsigned long offset,uint64_t flags,uint64_t cgroup,uint64_t mapcnt,uint64_t pme)631 static void add_page(unsigned long voffset, unsigned long offset,
632 uint64_t flags, uint64_t cgroup, uint64_t mapcnt,
633 uint64_t pme)
634 {
635 flags = kpageflags_flags(flags, pme);
636
637 if (!bit_mask_ok(flags))
638 return;
639
640 if (opt_cgroup && cgroup != (uint64_t)opt_cgroup)
641 return;
642
643 if (opt_hwpoison)
644 hwpoison_page(offset);
645 if (opt_unpoison)
646 unpoison_page(offset);
647
648 if (opt_mark_idle)
649 mark_page_idle(offset);
650
651 if (opt_list == 1)
652 show_page_range(voffset, offset, 1, flags, cgroup, mapcnt);
653 else if (opt_list == 2)
654 show_page(voffset, offset, flags, cgroup, mapcnt);
655
656 nr_pages[hash_slot(flags)]++;
657 total_pages++;
658 }
659
660 #define KPAGEFLAGS_BATCH (64 << 10) /* 64k pages */
walk_pfn(unsigned long voffset,unsigned long index,unsigned long count,uint64_t pme)661 static void walk_pfn(unsigned long voffset,
662 unsigned long index,
663 unsigned long count,
664 uint64_t pme)
665 {
666 uint64_t buf[KPAGEFLAGS_BATCH];
667 uint64_t cgi[KPAGEFLAGS_BATCH];
668 uint64_t cnt[KPAGEFLAGS_BATCH];
669 unsigned long batch;
670 unsigned long pages;
671 unsigned long i;
672
673 /*
674 * kpagecgroup_read() reads only if kpagecgroup were opened, but
675 * /proc/kpagecgroup might even not exist, so it's better to fill
676 * them with zeros here.
677 */
678 if (count == 1)
679 cgi[0] = 0;
680 else
681 memset(cgi, 0, sizeof cgi);
682
683 while (count) {
684 batch = min_t(unsigned long, count, KPAGEFLAGS_BATCH);
685 pages = kpageflags_read(buf, index, batch);
686 if (pages == 0)
687 break;
688
689 if (kpagecgroup_read(cgi, index, pages) != pages)
690 fatal("kpagecgroup returned fewer pages than expected");
691
692 if (kpagecount_read(cnt, index, pages) != pages)
693 fatal("kpagecount returned fewer pages than expected");
694
695 for (i = 0; i < pages; i++)
696 add_page(voffset + i, index + i,
697 buf[i], cgi[i], cnt[i], pme);
698
699 index += pages;
700 count -= pages;
701 }
702 }
703
walk_swap(unsigned long voffset,uint64_t pme)704 static void walk_swap(unsigned long voffset, uint64_t pme)
705 {
706 uint64_t flags = kpageflags_flags(0, pme);
707
708 if (!bit_mask_ok(flags))
709 return;
710
711 if (opt_cgroup)
712 return;
713
714 if (opt_list == 1)
715 show_page_range(voffset, pagemap_swap_offset(pme),
716 1, flags, 0, 0);
717 else if (opt_list == 2)
718 show_page(voffset, pagemap_swap_offset(pme), flags, 0, 0);
719
720 nr_pages[hash_slot(flags)]++;
721 total_pages++;
722 }
723
724 #define PAGEMAP_BATCH (64 << 10)
walk_vma(unsigned long index,unsigned long count)725 static void walk_vma(unsigned long index, unsigned long count)
726 {
727 uint64_t buf[PAGEMAP_BATCH];
728 unsigned long batch;
729 unsigned long pages;
730 unsigned long pfn;
731 unsigned long i;
732
733 while (count) {
734 batch = min_t(unsigned long, count, PAGEMAP_BATCH);
735 pages = pagemap_read(buf, index, batch);
736 if (pages == 0)
737 break;
738
739 for (i = 0; i < pages; i++) {
740 pfn = pagemap_pfn(buf[i]);
741 if (pfn)
742 walk_pfn(index + i, pfn, 1, buf[i]);
743 if (buf[i] & PM_SWAP)
744 walk_swap(index + i, buf[i]);
745 }
746
747 index += pages;
748 count -= pages;
749 }
750 }
751
walk_task(unsigned long index,unsigned long count)752 static void walk_task(unsigned long index, unsigned long count)
753 {
754 const unsigned long end = index + count;
755 unsigned long start;
756 int i = 0;
757
758 while (index < end) {
759
760 while (pg_end[i] <= index)
761 if (++i >= nr_vmas)
762 return;
763 if (pg_start[i] >= end)
764 return;
765
766 start = max_t(unsigned long, pg_start[i], index);
767 index = min_t(unsigned long, pg_end[i], end);
768
769 assert(start < index);
770 walk_vma(start, index - start);
771 }
772 }
773
add_addr_range(unsigned long offset,unsigned long size)774 static void add_addr_range(unsigned long offset, unsigned long size)
775 {
776 if (nr_addr_ranges >= MAX_ADDR_RANGES)
777 fatal("too many addr ranges\n");
778
779 opt_offset[nr_addr_ranges] = offset;
780 opt_size[nr_addr_ranges] = min_t(unsigned long, size, ULONG_MAX-offset);
781 nr_addr_ranges++;
782 }
783
walk_addr_ranges(void)784 static void walk_addr_ranges(void)
785 {
786 int i;
787
788 kpageflags_fd = checked_open(opt_kpageflags, O_RDONLY);
789
790 if (!nr_addr_ranges)
791 add_addr_range(0, ULONG_MAX);
792
793 for (i = 0; i < nr_addr_ranges; i++)
794 if (!opt_pid)
795 walk_pfn(opt_offset[i], opt_offset[i], opt_size[i], 0);
796 else
797 walk_task(opt_offset[i], opt_size[i]);
798
799 if (opt_mark_idle)
800 mark_page_idle(0);
801
802 close(kpageflags_fd);
803 }
804
805
806 /*
807 * user interface
808 */
809
page_flag_type(uint64_t flag)810 static const char *page_flag_type(uint64_t flag)
811 {
812 if (flag & KPF_HACKERS_BITS)
813 return "(r)";
814 if (flag & KPF_OVERLOADED_BITS)
815 return "(o)";
816 return " ";
817 }
818
usage(void)819 static void usage(void)
820 {
821 size_t i, j;
822
823 printf(
824 "page-types [options]\n"
825 " -r|--raw Raw mode, for kernel developers\n"
826 " -d|--describe flags Describe flags\n"
827 " -a|--addr addr-spec Walk a range of pages\n"
828 " -b|--bits bits-spec Walk pages with specified bits\n"
829 " -c|--cgroup path|@inode Walk pages within memory cgroup\n"
830 " -p|--pid pid Walk process address space\n"
831 " -f|--file filename Walk file address space\n"
832 " -i|--mark-idle Mark pages idle\n"
833 " -l|--list Show page details in ranges\n"
834 " -L|--list-each Show page details one by one\n"
835 " -C|--list-cgroup Show cgroup inode for pages\n"
836 " -M|--list-mapcnt Show page map count\n"
837 " -N|--no-summary Don't show summary info\n"
838 " -X|--hwpoison hwpoison pages\n"
839 " -x|--unpoison unpoison pages\n"
840 " -F|--kpageflags filename kpageflags file to parse\n"
841 " -h|--help Show this usage message\n"
842 "flags:\n"
843 " 0x10 bitfield format, e.g.\n"
844 " anon bit-name, e.g.\n"
845 " 0x10,anon comma-separated list, e.g.\n"
846 "addr-spec:\n"
847 " N one page at offset N (unit: pages)\n"
848 " N+M pages range from N to N+M-1\n"
849 " N,M pages range from N to M-1\n"
850 " N, pages range from N to end\n"
851 " ,M pages range from 0 to M-1\n"
852 "bits-spec:\n"
853 " bit1,bit2 (flags & (bit1|bit2)) != 0\n"
854 " bit1,bit2=bit1 (flags & (bit1|bit2)) == bit1\n"
855 " bit1,~bit2 (flags & (bit1|bit2)) == bit1\n"
856 " =bit1,bit2 flags == (bit1|bit2)\n"
857 "bit-names:\n"
858 );
859
860 for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
861 if (!page_flag_names[i])
862 continue;
863 printf("%16s%s", page_flag_names[i] + 2,
864 page_flag_type(1ULL << i));
865 if (++j > 3) {
866 j = 0;
867 putchar('\n');
868 }
869 }
870 printf("\n "
871 "(r) raw mode bits (o) overloaded bits\n");
872 }
873
parse_number(const char * str)874 static unsigned long long parse_number(const char *str)
875 {
876 unsigned long long n;
877
878 n = strtoll(str, NULL, 0);
879
880 if (n == 0 && str[0] != '0')
881 fatal("invalid name or number: %s\n", str);
882
883 return n;
884 }
885
parse_pid(const char * str)886 static void parse_pid(const char *str)
887 {
888 FILE *file;
889 char buf[5000];
890
891 opt_pid = parse_number(str);
892
893 sprintf(buf, "/proc/%d/pagemap", opt_pid);
894 pagemap_fd = checked_open(buf, O_RDONLY);
895
896 sprintf(buf, "/proc/%d/maps", opt_pid);
897 file = fopen(buf, "r");
898 if (!file) {
899 perror(buf);
900 exit(EXIT_FAILURE);
901 }
902
903 while (fgets(buf, sizeof(buf), file) != NULL) {
904 unsigned long vm_start;
905 unsigned long vm_end;
906 unsigned long long pgoff;
907 int major, minor;
908 char r, w, x, s;
909 unsigned long ino;
910 int n;
911
912 n = sscanf(buf, "%lx-%lx %c%c%c%c %llx %x:%x %lu",
913 &vm_start,
914 &vm_end,
915 &r, &w, &x, &s,
916 &pgoff,
917 &major, &minor,
918 &ino);
919 if (n < 10) {
920 fprintf(stderr, "unexpected line: %s\n", buf);
921 continue;
922 }
923 pg_start[nr_vmas] = vm_start / page_size;
924 pg_end[nr_vmas] = vm_end / page_size;
925 if (++nr_vmas >= MAX_VMAS) {
926 fprintf(stderr, "too many VMAs\n");
927 break;
928 }
929 }
930 fclose(file);
931 }
932
show_file(const char * name,const struct stat * st)933 static void show_file(const char *name, const struct stat *st)
934 {
935 unsigned long long size = st->st_size;
936 char atime[64], mtime[64];
937 long now = time(NULL);
938
939 printf("%s\tInode: %u\tSize: %llu (%llu pages)\n",
940 name, (unsigned)st->st_ino,
941 size, (size + page_size - 1) / page_size);
942
943 strftime(atime, sizeof(atime), "%c", localtime(&st->st_atime));
944 strftime(mtime, sizeof(mtime), "%c", localtime(&st->st_mtime));
945
946 printf("Modify: %s (%ld seconds ago)\nAccess: %s (%ld seconds ago)\n",
947 mtime, now - st->st_mtime,
948 atime, now - st->st_atime);
949 }
950
951 static sigjmp_buf sigbus_jmp;
952
953 static void * volatile sigbus_addr;
954
sigbus_handler(int sig,siginfo_t * info,void * ucontex)955 static void sigbus_handler(int sig, siginfo_t *info, void *ucontex)
956 {
957 (void)sig;
958 (void)ucontex;
959 sigbus_addr = info ? info->si_addr : NULL;
960 siglongjmp(sigbus_jmp, 1);
961 }
962
963 static struct sigaction sigbus_action = {
964 .sa_sigaction = sigbus_handler,
965 .sa_flags = SA_SIGINFO,
966 };
967
walk_file(const char * name,const struct stat * st)968 static void walk_file(const char *name, const struct stat *st)
969 {
970 uint8_t vec[PAGEMAP_BATCH];
971 uint64_t buf[PAGEMAP_BATCH], flags;
972 uint64_t cgroup = 0;
973 uint64_t mapcnt = 0;
974 unsigned long nr_pages, pfn, i;
975 off_t off, end = st->st_size;
976 int fd;
977 ssize_t len;
978 void *ptr;
979 int first = 1;
980
981 fd = checked_open(name, O_RDONLY|O_NOATIME|O_NOFOLLOW);
982
983 for (off = 0; off < end; off += len) {
984 nr_pages = (end - off + page_size - 1) / page_size;
985 if (nr_pages > PAGEMAP_BATCH)
986 nr_pages = PAGEMAP_BATCH;
987 len = nr_pages * page_size;
988
989 ptr = mmap(NULL, len, PROT_READ, MAP_SHARED, fd, off);
990 if (ptr == MAP_FAILED)
991 fatal("mmap failed: %s", name);
992
993 /* determine cached pages */
994 if (mincore(ptr, len, vec))
995 fatal("mincore failed: %s", name);
996
997 /* turn off readahead */
998 if (madvise(ptr, len, MADV_RANDOM))
999 fatal("madvice failed: %s", name);
1000
1001 if (sigsetjmp(sigbus_jmp, 1)) {
1002 end = off + sigbus_addr ? sigbus_addr - ptr : 0;
1003 fprintf(stderr, "got sigbus at offset %lld: %s\n",
1004 (long long)end, name);
1005 goto got_sigbus;
1006 }
1007
1008 /* populate ptes */
1009 for (i = 0; i < nr_pages ; i++) {
1010 if (vec[i] & 1)
1011 (void)*(volatile int *)(ptr + i * page_size);
1012 }
1013 got_sigbus:
1014
1015 /* turn off harvesting reference bits */
1016 if (madvise(ptr, len, MADV_SEQUENTIAL))
1017 fatal("madvice failed: %s", name);
1018
1019 if (pagemap_read(buf, (unsigned long)ptr / page_size,
1020 nr_pages) != nr_pages)
1021 fatal("cannot read pagemap");
1022
1023 munmap(ptr, len);
1024
1025 for (i = 0; i < nr_pages; i++) {
1026 pfn = pagemap_pfn(buf[i]);
1027 if (!pfn)
1028 continue;
1029 if (!kpageflags_read(&flags, pfn, 1))
1030 continue;
1031 if (!kpagecgroup_read(&cgroup, pfn, 1))
1032 fatal("kpagecgroup_read failed");
1033 if (!kpagecount_read(&mapcnt, pfn, 1))
1034 fatal("kpagecount_read failed");
1035 if (first && opt_list) {
1036 first = 0;
1037 flush_page_range();
1038 show_file(name, st);
1039 }
1040 add_page(off / page_size + i, pfn,
1041 flags, cgroup, mapcnt, buf[i]);
1042 }
1043 }
1044
1045 close(fd);
1046 }
1047
walk_tree(const char * name,const struct stat * st,int type,struct FTW * f)1048 int walk_tree(const char *name, const struct stat *st, int type, struct FTW *f)
1049 {
1050 (void)f;
1051 switch (type) {
1052 case FTW_F:
1053 if (S_ISREG(st->st_mode))
1054 walk_file(name, st);
1055 break;
1056 case FTW_DNR:
1057 fprintf(stderr, "cannot read dir: %s\n", name);
1058 break;
1059 }
1060 return 0;
1061 }
1062
walk_page_cache(void)1063 static void walk_page_cache(void)
1064 {
1065 struct stat st;
1066
1067 kpageflags_fd = checked_open(opt_kpageflags, O_RDONLY);
1068 pagemap_fd = checked_open("/proc/self/pagemap", O_RDONLY);
1069 sigaction(SIGBUS, &sigbus_action, NULL);
1070
1071 if (stat(opt_file, &st))
1072 fatal("stat failed: %s\n", opt_file);
1073
1074 if (S_ISREG(st.st_mode)) {
1075 walk_file(opt_file, &st);
1076 } else if (S_ISDIR(st.st_mode)) {
1077 /* do not follow symlinks and mountpoints */
1078 if (nftw(opt_file, walk_tree, 64, FTW_MOUNT | FTW_PHYS) < 0)
1079 fatal("nftw failed: %s\n", opt_file);
1080 } else
1081 fatal("unhandled file type: %s\n", opt_file);
1082
1083 close(kpageflags_fd);
1084 close(pagemap_fd);
1085 signal(SIGBUS, SIG_DFL);
1086 }
1087
parse_file(const char * name)1088 static void parse_file(const char *name)
1089 {
1090 opt_file = name;
1091 }
1092
parse_cgroup(const char * path)1093 static void parse_cgroup(const char *path)
1094 {
1095 if (path[0] == '@') {
1096 opt_cgroup = parse_number(path + 1);
1097 return;
1098 }
1099
1100 struct stat st;
1101
1102 if (stat(path, &st))
1103 fatal("stat failed: %s: %m\n", path);
1104
1105 if (!S_ISDIR(st.st_mode))
1106 fatal("cgroup supposed to be a directory: %s\n", path);
1107
1108 opt_cgroup = st.st_ino;
1109 }
1110
parse_addr_range(const char * optarg)1111 static void parse_addr_range(const char *optarg)
1112 {
1113 unsigned long offset;
1114 unsigned long size;
1115 char *p;
1116
1117 p = strchr(optarg, ',');
1118 if (!p)
1119 p = strchr(optarg, '+');
1120
1121 if (p == optarg) {
1122 offset = 0;
1123 size = parse_number(p + 1);
1124 } else if (p) {
1125 offset = parse_number(optarg);
1126 if (p[1] == '\0')
1127 size = ULONG_MAX;
1128 else {
1129 size = parse_number(p + 1);
1130 if (*p == ',') {
1131 if (size < offset)
1132 fatal("invalid range: %lu,%lu\n",
1133 offset, size);
1134 size -= offset;
1135 }
1136 }
1137 } else {
1138 offset = parse_number(optarg);
1139 size = 1;
1140 }
1141
1142 add_addr_range(offset, size);
1143 }
1144
add_bits_filter(uint64_t mask,uint64_t bits)1145 static void add_bits_filter(uint64_t mask, uint64_t bits)
1146 {
1147 if (nr_bit_filters >= MAX_BIT_FILTERS)
1148 fatal("too much bit filters\n");
1149
1150 opt_mask[nr_bit_filters] = mask;
1151 opt_bits[nr_bit_filters] = bits;
1152 nr_bit_filters++;
1153 }
1154
parse_flag_name(const char * str,int len)1155 static uint64_t parse_flag_name(const char *str, int len)
1156 {
1157 size_t i;
1158
1159 if (!*str || !len)
1160 return 0;
1161
1162 if (len <= 8 && !strncmp(str, "compound", len))
1163 return BITS_COMPOUND;
1164
1165 for (i = 0; i < ARRAY_SIZE(page_flag_names); i++) {
1166 if (!page_flag_names[i])
1167 continue;
1168 if (!strncmp(str, page_flag_names[i] + 2, len))
1169 return 1ULL << i;
1170 }
1171
1172 return parse_number(str);
1173 }
1174
parse_flag_names(const char * str,int all)1175 static uint64_t parse_flag_names(const char *str, int all)
1176 {
1177 const char *p = str;
1178 uint64_t flags = 0;
1179
1180 while (1) {
1181 if (*p == ',' || *p == '=' || *p == '\0') {
1182 if ((*str != '~') || (*str == '~' && all && *++str))
1183 flags |= parse_flag_name(str, p - str);
1184 if (*p != ',')
1185 break;
1186 str = p + 1;
1187 }
1188 p++;
1189 }
1190
1191 return flags;
1192 }
1193
parse_bits_mask(const char * optarg)1194 static void parse_bits_mask(const char *optarg)
1195 {
1196 uint64_t mask;
1197 uint64_t bits;
1198 const char *p;
1199
1200 p = strchr(optarg, '=');
1201 if (p == optarg) {
1202 mask = KPF_ALL_BITS;
1203 bits = parse_flag_names(p + 1, 0);
1204 } else if (p) {
1205 mask = parse_flag_names(optarg, 0);
1206 bits = parse_flag_names(p + 1, 0);
1207 } else if (strchr(optarg, '~')) {
1208 mask = parse_flag_names(optarg, 1);
1209 bits = parse_flag_names(optarg, 0);
1210 } else {
1211 mask = parse_flag_names(optarg, 0);
1212 bits = KPF_ALL_BITS;
1213 }
1214
1215 add_bits_filter(mask, bits);
1216 }
1217
parse_kpageflags(const char * name)1218 static void parse_kpageflags(const char *name)
1219 {
1220 opt_kpageflags = name;
1221 }
1222
describe_flags(const char * optarg)1223 static void describe_flags(const char *optarg)
1224 {
1225 uint64_t flags = parse_flag_names(optarg, 0);
1226
1227 printf("0x%016llx\t%s\t%s\n",
1228 (unsigned long long)flags,
1229 page_flag_name(flags),
1230 page_flag_longname(flags));
1231 }
1232
1233 static const struct option opts[] = {
1234 { "raw" , 0, NULL, 'r' },
1235 { "pid" , 1, NULL, 'p' },
1236 { "file" , 1, NULL, 'f' },
1237 { "addr" , 1, NULL, 'a' },
1238 { "bits" , 1, NULL, 'b' },
1239 { "cgroup" , 1, NULL, 'c' },
1240 { "describe" , 1, NULL, 'd' },
1241 { "mark-idle" , 0, NULL, 'i' },
1242 { "list" , 0, NULL, 'l' },
1243 { "list-each" , 0, NULL, 'L' },
1244 { "list-cgroup", 0, NULL, 'C' },
1245 { "list-mapcnt", 0, NULL, 'M' },
1246 { "no-summary", 0, NULL, 'N' },
1247 { "hwpoison" , 0, NULL, 'X' },
1248 { "unpoison" , 0, NULL, 'x' },
1249 { "kpageflags", 0, NULL, 'F' },
1250 { "help" , 0, NULL, 'h' },
1251 { NULL , 0, NULL, 0 }
1252 };
1253
main(int argc,char * argv[])1254 int main(int argc, char *argv[])
1255 {
1256 int c;
1257
1258 page_size = getpagesize();
1259
1260 while ((c = getopt_long(argc, argv,
1261 "rp:f:a:b:d:c:CilLMNXxF:h",
1262 opts, NULL)) != -1) {
1263 switch (c) {
1264 case 'r':
1265 opt_raw = 1;
1266 break;
1267 case 'p':
1268 parse_pid(optarg);
1269 break;
1270 case 'f':
1271 parse_file(optarg);
1272 break;
1273 case 'a':
1274 parse_addr_range(optarg);
1275 break;
1276 case 'b':
1277 parse_bits_mask(optarg);
1278 break;
1279 case 'c':
1280 parse_cgroup(optarg);
1281 break;
1282 case 'C':
1283 opt_list_cgroup = 1;
1284 break;
1285 case 'd':
1286 describe_flags(optarg);
1287 exit(0);
1288 case 'i':
1289 opt_mark_idle = 1;
1290 break;
1291 case 'l':
1292 opt_list = 1;
1293 break;
1294 case 'L':
1295 opt_list = 2;
1296 break;
1297 case 'M':
1298 opt_list_mapcnt = 1;
1299 break;
1300 case 'N':
1301 opt_no_summary = 1;
1302 break;
1303 case 'X':
1304 opt_hwpoison = 1;
1305 prepare_hwpoison_fd();
1306 break;
1307 case 'x':
1308 opt_unpoison = 1;
1309 prepare_hwpoison_fd();
1310 break;
1311 case 'F':
1312 parse_kpageflags(optarg);
1313 break;
1314 case 'h':
1315 usage();
1316 exit(0);
1317 default:
1318 usage();
1319 exit(1);
1320 }
1321 }
1322
1323 if (!opt_kpageflags)
1324 opt_kpageflags = PROC_KPAGEFLAGS;
1325
1326 if (opt_cgroup || opt_list_cgroup)
1327 kpagecgroup_fd = checked_open(PROC_KPAGECGROUP, O_RDONLY);
1328
1329 if (opt_list && opt_list_mapcnt)
1330 kpagecount_fd = checked_open(PROC_KPAGECOUNT, O_RDONLY);
1331
1332 if (opt_mark_idle && opt_file)
1333 page_idle_fd = checked_open(SYS_KERNEL_MM_PAGE_IDLE, O_RDWR);
1334
1335 if (opt_list && opt_pid)
1336 printf("voffset\t");
1337 if (opt_list && opt_file)
1338 printf("foffset\t");
1339 if (opt_list && opt_list_cgroup)
1340 printf("cgroup\t");
1341 if (opt_list && opt_list_mapcnt)
1342 printf("map-cnt\t");
1343
1344 if (opt_list == 1)
1345 printf("offset\tlen\tflags\n");
1346 if (opt_list == 2)
1347 printf("offset\tflags\n");
1348
1349 if (opt_file)
1350 walk_page_cache();
1351 else
1352 walk_addr_ranges();
1353
1354 if (opt_list == 1)
1355 flush_page_range();
1356
1357 if (opt_no_summary)
1358 return 0;
1359
1360 if (opt_list)
1361 printf("\n\n");
1362
1363 show_summary();
1364
1365 if (opt_list_mapcnt)
1366 close(kpagecount_fd);
1367
1368 if (page_idle_fd >= 0)
1369 close(page_idle_fd);
1370
1371 return 0;
1372 }
1373