tools/vm/page-types.c

   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 <fengguang.wu@intel.com>
  20  */
  21
  22 #define _FILE_OFFSET_BITS 64
  23 #define _GNU_SOURCE
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <unistd.h>
  27 #include <stdint.h>
  28 #include <stdarg.h>
  29 #include <string.h>
  30 #include <getopt.h>
  31 #include <limits.h>
  32 #include <assert.h>
  33 #include <ftw.h>
  34 #include <time.h>
  35 #include <setjmp.h>
  36 #include <signal.h>
  37 #include <sys/types.h>
  38 #include <sys/errno.h>
  39 #include <sys/fcntl.h>
  40 #include <sys/mount.h>
  41 #include <sys/statfs.h>
  42 #include <sys/mman.h>
  43 #include "../../include/uapi/linux/magic.h"
  44 #include "../../include/uapi/linux/kernel-page-flags.h"
  45 #include <api/fs/fs.h>
  46
  47 #ifndef MAX_PATH
  48 # define MAX_PATH 256
  49 #endif
  50
  51 #ifndef STR
  52 # define _STR(x) #x
  53 # define STR(x) _STR(x)
  54 #endif
  55
  56 /*
  57  * pagemap kernel ABI bits
  58  */
  59
  60 #define PM_ENTRY_BYTES          8
  61 #define PM_PFRAME_BITS          55
  62 #define PM_PFRAME_MASK          ((1LL << PM_PFRAME_BITS) - 1)
  63 #define PM_PFRAME(x)            ((x) & PM_PFRAME_MASK)
  64 #define MAX_SWAPFILES_SHIFT     5
  65 #define PM_SWAP_OFFSET(x)       (((x) & PM_PFRAME_MASK) >> MAX_SWAPFILES_SHIFT)
  66 #define PM_SOFT_DIRTY           (1ULL << 55)
  67 #define PM_MMAP_EXCLUSIVE       (1ULL << 56)
  68 #define PM_FILE                 (1ULL << 61)
  69 #define PM_SWAP                 (1ULL << 62)
  70 #define PM_PRESENT              (1ULL << 63)
  71
  72 /*
  73  * kernel page flags
  74  */
  75
  76 #define KPF_BYTES               8
  77 #define PROC_KPAGEFLAGS         "/proc/kpageflags"
  78 #define PROC_KPAGECGROUP        "/proc/kpagecgroup"
  79
  80 /* [32-] kernel hacking assistances */
  81 #define KPF_RESERVED            32
  82 #define KPF_MLOCKED             33
  83 #define KPF_MAPPEDTODISK        34
  84 #define KPF_PRIVATE             35
  85 #define KPF_PRIVATE_2           36
  86 #define KPF_OWNER_PRIVATE       37
  87 #define KPF_ARCH                38
  88 #define KPF_UNCACHED            39
  89 #define KPF_SOFTDIRTY           40
  90
  91 /* [48-] take some arbitrary free slots for expanding overloaded flags
  92  * not part of kernel API
  93  */
  94 #define KPF_READAHEAD           48
  95 #define KPF_SLOB_FREE           49
  96 #define KPF_SLUB_FROZEN         50
  97 #define KPF_SLUB_DEBUG          51
  98 #define KPF_FILE                61
  99 #define KPF_SWAP                62
 100 #define KPF_MMAP_EXCLUSIVE      63
 101
 102 #define KPF_ALL_BITS            ((uint64_t)~0ULL)
 103 #define KPF_HACKERS_BITS        (0xffffULL << 32)
 104 #define KPF_OVERLOADED_BITS     (0xffffULL << 48)
 105 #define BIT(name)               (1ULL << KPF_##name)
 106 #define BITS_COMPOUND           (BIT(COMPOUND_HEAD) | BIT(COMPOUND_TAIL))
 107
 108 static const char * const page_flag_names[] = {
 109         [KPF_LOCKED]            = "L:locked",
 110         [KPF_ERROR]             = "E:error",
 111         [KPF_REFERENCED]        = "R:referenced",
 112         [KPF_UPTODATE]          = "U:uptodate",
 113         [KPF_DIRTY]             = "D:dirty",
 114         [KPF_LRU]               = "l:lru",
 115         [KPF_ACTIVE]            = "A:active",
 116         [KPF_SLAB]              = "S:slab",
 117         [KPF_WRITEBACK]         = "W:writeback",
 118         [KPF_RECLAIM]           = "I:reclaim",
 119         [KPF_BUDDY]             = "B:buddy",
 120
 121         [KPF_MMAP]              = "M:mmap",
 122         [KPF_ANON]              = "a:anonymous",
 123         [KPF_SWAPCACHE]         = "s:swapcache",
 124         [KPF_SWAPBACKED]        = "b:swapbacked",
 125         [KPF_COMPOUND_HEAD]     = "H:compound_head",
 126         [KPF_COMPOUND_TAIL]     = "T:compound_tail",
 127         [KPF_HUGE]              = "G:huge",
 128         [KPF_UNEVICTABLE]       = "u:unevictable",
 129         [KPF_HWPOISON]          = "X:hwpoison",
 130         [KPF_NOPAGE]            = "n:nopage",
 131         [KPF_KSM]               = "x:ksm",
 132         [KPF_THP]               = "t:thp",
 133         [KPF_BALLOON]           = "o:balloon",
 134         [KPF_ZERO_PAGE]         = "z:zero_page",
 135         [KPF_IDLE]              = "i:idle_page",
 136
 137         [KPF_RESERVED]          = "r:reserved",
 138         [KPF_MLOCKED]           = "m:mlocked",
 139         [KPF_MAPPEDTODISK]      = "d:mappedtodisk",
 140         [KPF_PRIVATE]           = "P:private",
 141         [KPF_PRIVATE_2]         = "p:private_2",
 142         [KPF_OWNER_PRIVATE]     = "O:owner_private",
 143         [KPF_ARCH]              = "h:arch",
 144         [KPF_UNCACHED]          = "c:uncached",
 145         [KPF_SOFTDIRTY]         = "f:softdirty",
 146
 147         [KPF_READAHEAD]         = "I:readahead",
 148         [KPF_SLOB_FREE]         = "P:slob_free",
 149         [KPF_SLUB_FROZEN]       = "A:slub_frozen",
 150         [KPF_SLUB_DEBUG]        = "E:slub_debug",
 151
 152         [KPF_FILE]              = "F:file",
 153         [KPF_SWAP]              = "w:swap",
 154         [KPF_MMAP_EXCLUSIVE]    = "1:mmap_exclusive",
 155 };
 156
 157
 158 /*
 159  * data structures
 160  */
 161
 162 static int              opt_raw;        /* for kernel developers */
 163 static int              opt_list;       /* list pages (in ranges) */
 164 static int              opt_no_summary; /* don't show summary */
 165 static pid_t            opt_pid;        /* process to walk */
 166 const char *            opt_file;       /* file or directory path */
 167 static uint64_t         opt_cgroup;     /* cgroup inode */
 168 static int              opt_list_cgroup;/* list page cgroup */
 169
 170 #define MAX_ADDR_RANGES 1024
 171 static int              nr_addr_ranges;
 172 static unsigned long    opt_offset[MAX_ADDR_RANGES];
 173 static unsigned long    opt_size[MAX_ADDR_RANGES];
 174
 175 #define MAX_VMAS        10240
 176 static int              nr_vmas;
 177 static unsigned long    pg_start[MAX_VMAS];
 178 static unsigned long    pg_end[MAX_VMAS];
 179
 180 #define MAX_BIT_FILTERS 64
 181 static int              nr_bit_filters;
 182 static uint64_t         opt_mask[MAX_BIT_FILTERS];
 183 static uint64_t         opt_bits[MAX_BIT_FILTERS];
 184
 185 static int              page_size;
 186
 187 static int              pagemap_fd;
 188 static int              kpageflags_fd;
 189 static int              kpagecgroup_fd = -1;
 190
 191 static int              opt_hwpoison;
 192 static int              opt_unpoison;
 193
 194 static const char       *hwpoison_debug_fs;
 195 static int              hwpoison_inject_fd;
 196 static int              hwpoison_forget_fd;
 197
 198 #define HASH_SHIFT      13
 199 #define HASH_SIZE       (1 << HASH_SHIFT)
 200 #define HASH_MASK       (HASH_SIZE - 1)
 201 #define HASH_KEY(flags) (flags & HASH_MASK)
 202
 203 static unsigned long    total_pages;
 204 static unsigned long    nr_pages[HASH_SIZE];
 205 static uint64_t         page_flags[HASH_SIZE];
 206
 207
 208 /*
 209  * helper functions
 210  */
 211
 212 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
 213
 214 #define min_t(type, x, y) ({                    \
 215         type __min1 = (x);                      \
 216         type __min2 = (y);                      \
 217         __min1 < __min2 ? __min1 : __min2; })
 218
 219 #define max_t(type, x, y) ({                    \
 220         type __max1 = (x);                      \
 221         type __max2 = (y);                      \
 222         __max1 > __max2 ? __max1 : __max2; })
 223
 224 static unsigned long pages2mb(unsigned long pages)
 225 {
 226         return (pages * page_size) >> 20;
 227 }
 228
 229 static void fatal(const char *x, ...)
 230 {
 231         va_list ap;
 232
 233         va_start(ap, x);
 234         vfprintf(stderr, x, ap);
 235         va_end(ap);
 236         exit(EXIT_FAILURE);
 237 }
 238
 239 static int checked_open(const char *pathname, int flags)
 240 {
 241         int fd = open(pathname, flags);
 242
 243         if (fd < 0) {
 244                 perror(pathname);
 245                 exit(EXIT_FAILURE);
 246         }
 247
 248         return fd;
 249 }
 250
 251 /*
 252  * pagemap/kpageflags routines
 253  */
 254
 255 static unsigned long do_u64_read(int fd, char *name,
 256                                  uint64_t *buf,
 257                                  unsigned long index,
 258                                  unsigned long count)
 259 {
 260         long bytes;
 261
 262         if (index > ULONG_MAX / 8)
 263                 fatal("index overflow: %lu\n", index);
 264
 265         bytes = pread(fd, buf, count * 8, (off_t)index * 8);
 266         if (bytes < 0) {
 267                 perror(name);
 268                 exit(EXIT_FAILURE);
 269         }
 270         if (bytes % 8)
 271                 fatal("partial read: %lu bytes\n", bytes);
 272
 273         return bytes / 8;
 274 }
 275
 276 static unsigned long kpageflags_read(uint64_t *buf,
 277                                      unsigned long index,
 278                                      unsigned long pages)
 279 {
 280         return do_u64_read(kpageflags_fd, PROC_KPAGEFLAGS, buf, index, pages);
 281 }
 282
 283 static unsigned long kpagecgroup_read(uint64_t *buf,
 284                                       unsigned long index,
 285                                       unsigned long pages)
 286 {
 287         if (kpagecgroup_fd < 0)
 288                 return pages;
 289
 290         return do_u64_read(kpagecgroup_fd, PROC_KPAGEFLAGS, buf, index, pages);
 291 }
 292
 293 static unsigned long pagemap_read(uint64_t *buf,
 294                                   unsigned long index,
 295                                   unsigned long pages)
 296 {
 297         return do_u64_read(pagemap_fd, "/proc/pid/pagemap", buf, index, pages);
 298 }
 299
 300 static unsigned long pagemap_pfn(uint64_t val)
 301 {
 302         unsigned long pfn;
 303
 304         if (val & PM_PRESENT)
 305                 pfn = PM_PFRAME(val);
 306         else
 307                 pfn = 0;
 308
 309         return pfn;
 310 }
 311
 312 static unsigned long pagemap_swap_offset(uint64_t val)
 313 {
 314         return val & PM_SWAP ? PM_SWAP_OFFSET(val) : 0;
 315 }
 316
 317 /*
 318  * page flag names
 319  */
 320
 321 static char *page_flag_name(uint64_t flags)
 322 {
 323         static char buf[65];
 324         int present;
 325         size_t i, j;
 326
 327         for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
 328                 present = (flags >> i) & 1;
 329                 if (!page_flag_names[i]) {
 330                         if (present)
 331                                 fatal("unknown flag bit %d\n", i);
 332                         continue;
 333                 }
 334                 buf[j++] = present ? page_flag_names[i][0] : '_';
 335         }
 336
 337         return buf;
 338 }
 339
 340 static char *page_flag_longname(uint64_t flags)
 341 {
 342         static char buf[1024];
 343         size_t i, n;
 344
 345         for (i = 0, n = 0; i < ARRAY_SIZE(page_flag_names); i++) {
 346                 if (!page_flag_names[i])
 347                         continue;
 348                 if ((flags >> i) & 1)
 349                         n += snprintf(buf + n, sizeof(buf) - n, "%s,",
 350                                         page_flag_names[i] + 2);
 351         }
 352         if (n)
 353                 n--;
 354         buf[n] = '\0';
 355
 356         return buf;
 357 }
 358
 359
 360 /*
 361  * page list and summary
 362  */
 363
 364 static void show_page_range(unsigned long voffset, unsigned long offset,
 365                             unsigned long size, uint64_t flags, uint64_t cgroup)
 366 {
 367         static uint64_t      flags0;
 368         static uint64_t      cgroup0;
 369         static unsigned long voff;
 370         static unsigned long index;
 371         static unsigned long count;
 372
 373         if (flags == flags0 && cgroup == cgroup0 && offset == index + count &&
 374             size && voffset == voff + count) {
 375                 count += size;
 376                 return;
 377         }
 378
 379         if (count) {
 380                 if (opt_pid)
 381                         printf("%lx\t", voff);
 382                 if (opt_file)
 383                         printf("%lu\t", voff);
 384                 if (opt_list_cgroup)
 385                         printf("@%llu\t", (unsigned long long)cgroup0);
 386                 printf("%lx\t%lx\t%s\n",
 387                                 index, count, page_flag_name(flags0));
 388         }
 389
 390         flags0 = flags;
 391         cgroup0= cgroup;
 392         index  = offset;
 393         voff   = voffset;
 394         count  = size;
 395 }
 396
 397 static void flush_page_range(void)
 398 {
 399         show_page_range(0, 0, 0, 0, 0);
 400 }
 401
 402 static void show_page(unsigned long voffset, unsigned long offset,
 403                       uint64_t flags, uint64_t cgroup)
 404 {
 405         if (opt_pid)
 406                 printf("%lx\t", voffset);
 407         if (opt_file)
 408                 printf("%lu\t", voffset);
 409         if (opt_list_cgroup)
 410                 printf("@%llu\t", (unsigned long long)cgroup);
 411         printf("%lx\t%s\n", offset, page_flag_name(flags));
 412 }
 413
 414 static void show_summary(void)
 415 {
 416         size_t i;
 417
 418         printf("             flags\tpage-count       MB"
 419                 "  symbolic-flags\t\t\tlong-symbolic-flags\n");
 420
 421         for (i = 0; i < ARRAY_SIZE(nr_pages); i++) {
 422                 if (nr_pages[i])
 423                         printf("0x%016llx\t%10lu %8lu  %s\t%s\n",
 424                                 (unsigned long long)page_flags[i],
 425                                 nr_pages[i],
 426                                 pages2mb(nr_pages[i]),
 427                                 page_flag_name(page_flags[i]),
 428                                 page_flag_longname(page_flags[i]));
 429         }
 430
 431         printf("             total\t%10lu %8lu\n",
 432                         total_pages, pages2mb(total_pages));
 433 }
 434
 435
 436 /*
 437  * page flag filters
 438  */
 439
 440 static int bit_mask_ok(uint64_t flags)
 441 {
 442         int i;
 443
 444         for (i = 0; i < nr_bit_filters; i++) {
 445                 if (opt_bits[i] == KPF_ALL_BITS) {
 446                         if ((flags & opt_mask[i]) == 0)
 447                                 return 0;
 448                 } else {
 449                         if ((flags & opt_mask[i]) != opt_bits[i])
 450                                 return 0;
 451                 }
 452         }
 453
 454         return 1;
 455 }
 456
 457 static uint64_t expand_overloaded_flags(uint64_t flags, uint64_t pme)
 458 {
 459         /* SLOB/SLUB overload several page flags */
 460         if (flags & BIT(SLAB)) {
 461                 if (flags & BIT(PRIVATE))
 462                         flags ^= BIT(PRIVATE) | BIT(SLOB_FREE);
 463                 if (flags & BIT(ACTIVE))
 464                         flags ^= BIT(ACTIVE) | BIT(SLUB_FROZEN);
 465                 if (flags & BIT(ERROR))
 466                         flags ^= BIT(ERROR) | BIT(SLUB_DEBUG);
 467         }
 468
 469         /* PG_reclaim is overloaded as PG_readahead in the read path */
 470         if ((flags & (BIT(RECLAIM) | BIT(WRITEBACK))) == BIT(RECLAIM))
 471                 flags ^= BIT(RECLAIM) | BIT(READAHEAD);
 472
 473         if (pme & PM_SOFT_DIRTY)
 474                 flags |= BIT(SOFTDIRTY);
 475         if (pme & PM_FILE)
 476                 flags |= BIT(FILE);
 477         if (pme & PM_SWAP)
 478                 flags |= BIT(SWAP);
 479         if (pme & PM_MMAP_EXCLUSIVE)
 480                 flags |= BIT(MMAP_EXCLUSIVE);
 481
 482         return flags;
 483 }
 484
 485 static uint64_t well_known_flags(uint64_t flags)
 486 {
 487         /* hide flags intended only for kernel hacker */
 488         flags &= ~KPF_HACKERS_BITS;
 489
 490         /* hide non-hugeTLB compound pages */
 491         if ((flags & BITS_COMPOUND) && !(flags & BIT(HUGE)))
 492                 flags &= ~BITS_COMPOUND;
 493
 494         return flags;
 495 }
 496
 497 static uint64_t kpageflags_flags(uint64_t flags, uint64_t pme)
 498 {
 499         if (opt_raw)
 500                 flags = expand_overloaded_flags(flags, pme);
 501         else
 502                 flags = well_known_flags(flags);
 503
 504         return flags;
 505 }
 506
 507 /*
 508  * page actions
 509  */
 510
 511 static void prepare_hwpoison_fd(void)
 512 {
 513         char buf[MAX_PATH + 1];
 514
 515         hwpoison_debug_fs = debugfs__mount();
 516         if (!hwpoison_debug_fs) {
 517                 perror("mount debugfs");
 518                 exit(EXIT_FAILURE);
 519         }
 520
 521         if (opt_hwpoison && !hwpoison_inject_fd) {
 522                 snprintf(buf, MAX_PATH, "%s/hwpoison/corrupt-pfn",
 523                         hwpoison_debug_fs);
 524                 hwpoison_inject_fd = checked_open(buf, O_WRONLY);
 525         }
 526
 527         if (opt_unpoison && !hwpoison_forget_fd) {
 528                 snprintf(buf, MAX_PATH, "%s/hwpoison/unpoison-pfn",
 529                         hwpoison_debug_fs);
 530                 hwpoison_forget_fd = checked_open(buf, O_WRONLY);
 531         }
 532 }
 533
 534 static int hwpoison_page(unsigned long offset)
 535 {
 536         char buf[100];
 537         int len;
 538
 539         len = sprintf(buf, "0x%lx\n", offset);
 540         len = write(hwpoison_inject_fd, buf, len);
 541         if (len < 0) {
 542                 perror("hwpoison inject");
 543                 return len;
 544         }
 545         return 0;
 546 }
 547
 548 static int unpoison_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_forget_fd, buf, len);
 555         if (len < 0) {
 556                 perror("hwpoison forget");
 557                 return len;
 558         }
 559         return 0;
 560 }
 561
 562 /*
 563  * page frame walker
 564  */
 565
 566 static size_t hash_slot(uint64_t flags)
 567 {
 568         size_t k = HASH_KEY(flags);
 569         size_t i;
 570
 571         /* Explicitly reserve slot 0 for flags 0: the following logic
 572          * cannot distinguish an unoccupied slot from slot (flags==0).
 573          */
 574         if (flags == 0)
 575                 return 0;
 576
 577         /* search through the remaining (HASH_SIZE-1) slots */
 578         for (i = 1; i < ARRAY_SIZE(page_flags); i++, k++) {
 579                 if (!k || k >= ARRAY_SIZE(page_flags))
 580                         k = 1;
 581                 if (page_flags[k] == 0) {
 582                         page_flags[k] = flags;
 583                         return k;
 584                 }
 585                 if (page_flags[k] == flags)
 586                         return k;
 587         }
 588
 589         fatal("hash table full: bump up HASH_SHIFT?\n");
 590         exit(EXIT_FAILURE);
 591 }
 592
 593 static void add_page(unsigned long voffset, unsigned long offset,
 594                      uint64_t flags, uint64_t cgroup, uint64_t pme)
 595 {
 596         flags = kpageflags_flags(flags, pme);
 597
 598         if (!bit_mask_ok(flags))
 599                 return;
 600
 601         if (opt_cgroup && cgroup != (uint64_t)opt_cgroup)
 602                 return;
 603
 604         if (opt_hwpoison)
 605                 hwpoison_page(offset);
 606         if (opt_unpoison)
 607                 unpoison_page(offset);
 608
 609         if (opt_list == 1)
 610                 show_page_range(voffset, offset, 1, flags, cgroup);
 611         else if (opt_list == 2)
 612                 show_page(voffset, offset, flags, cgroup);
 613
 614         nr_pages[hash_slot(flags)]++;
 615         total_pages++;
 616 }
 617
 618 #define KPAGEFLAGS_BATCH        (64 << 10)      /* 64k pages */
 619 static void walk_pfn(unsigned long voffset,
 620                      unsigned long index,
 621                      unsigned long count,
 622                      uint64_t pme)
 623 {
 624         uint64_t buf[KPAGEFLAGS_BATCH];
 625         uint64_t cgi[KPAGEFLAGS_BATCH];
 626         unsigned long batch;
 627         unsigned long pages;
 628         unsigned long i;
 629
 630         /*
 631          * kpagecgroup_read() reads only if kpagecgroup were opened, but
 632          * /proc/kpagecgroup might even not exist, so it's better to fill
 633          * them with zeros here.
 634          */
 635         if (count == 1)
 636                 cgi[0] = 0;
 637         else
 638                 memset(cgi, 0, sizeof cgi);
 639
 640         while (count) {
 641                 batch = min_t(unsigned long, count, KPAGEFLAGS_BATCH);
 642                 pages = kpageflags_read(buf, index, batch);
 643                 if (pages == 0)
 644                         break;
 645
 646                 if (kpagecgroup_read(cgi, index, pages) != pages)
 647                         fatal("kpagecgroup returned fewer pages than expected");
 648
 649                 for (i = 0; i < pages; i++)
 650                         add_page(voffset + i, index + i, buf[i], cgi[i], pme);
 651
 652                 index += pages;
 653                 count -= pages;
 654         }
 655 }
 656
 657 static void walk_swap(unsigned long voffset, uint64_t pme)
 658 {
 659         uint64_t flags = kpageflags_flags(0, pme);
 660
 661         if (!bit_mask_ok(flags))
 662                 return;
 663
 664         if (opt_cgroup)
 665                 return;
 666
 667         if (opt_list == 1)
 668                 show_page_range(voffset, pagemap_swap_offset(pme), 1, flags, 0);
 669         else if (opt_list == 2)
 670                 show_page(voffset, pagemap_swap_offset(pme), flags, 0);
 671
 672         nr_pages[hash_slot(flags)]++;
 673         total_pages++;
 674 }
 675
 676 #define PAGEMAP_BATCH   (64 << 10)
 677 static void walk_vma(unsigned long index, unsigned long count)
 678 {
 679         uint64_t buf[PAGEMAP_BATCH];
 680         unsigned long batch;
 681         unsigned long pages;
 682         unsigned long pfn;
 683         unsigned long i;
 684
 685         while (count) {
 686                 batch = min_t(unsigned long, count, PAGEMAP_BATCH);
 687                 pages = pagemap_read(buf, index, batch);
 688                 if (pages == 0)
 689                         break;
 690
 691                 for (i = 0; i < pages; i++) {
 692                         pfn = pagemap_pfn(buf[i]);
 693                         if (pfn)
 694                                 walk_pfn(index + i, pfn, 1, buf[i]);
 695                         if (buf[i] & PM_SWAP)
 696                                 walk_swap(index + i, buf[i]);
 697                 }
 698
 699                 index += pages;
 700                 count -= pages;
 701         }
 702 }
 703
 704 static void walk_task(unsigned long index, unsigned long count)
 705 {
 706         const unsigned long end = index + count;
 707         unsigned long start;
 708         int i = 0;
 709
 710         while (index < end) {
 711
 712                 while (pg_end[i] <= index)
 713                         if (++i >= nr_vmas)
 714                                 return;
 715                 if (pg_start[i] >= end)
 716                         return;
 717
 718                 start = max_t(unsigned long, pg_start[i], index);
 719                 index = min_t(unsigned long, pg_end[i], end);
 720
 721                 assert(start < index);
 722                 walk_vma(start, index - start);
 723         }
 724 }
 725
 726 static void add_addr_range(unsigned long offset, unsigned long size)
 727 {
 728         if (nr_addr_ranges >= MAX_ADDR_RANGES)
 729                 fatal("too many addr ranges\n");
 730
 731         opt_offset[nr_addr_ranges] = offset;
 732         opt_size[nr_addr_ranges] = min_t(unsigned long, size, ULONG_MAX-offset);
 733         nr_addr_ranges++;
 734 }
 735
 736 static void walk_addr_ranges(void)
 737 {
 738         int i;
 739
 740         kpageflags_fd = checked_open(PROC_KPAGEFLAGS, O_RDONLY);
 741
 742         if (!nr_addr_ranges)
 743                 add_addr_range(0, ULONG_MAX);
 744
 745         for (i = 0; i < nr_addr_ranges; i++)
 746                 if (!opt_pid)
 747                         walk_pfn(opt_offset[i], opt_offset[i], opt_size[i], 0);
 748                 else
 749                         walk_task(opt_offset[i], opt_size[i]);
 750
 751         close(kpageflags_fd);
 752 }
 753
 754
 755 /*
 756  * user interface
 757  */
 758
 759 static const char *page_flag_type(uint64_t flag)
 760 {
 761         if (flag & KPF_HACKERS_BITS)
 762                 return "(r)";
 763         if (flag & KPF_OVERLOADED_BITS)
 764                 return "(o)";
 765         return "   ";
 766 }
 767
 768 static void usage(void)
 769 {
 770         size_t i, j;
 771
 772         printf(
 773 "page-types [options]\n"
 774 "            -r|--raw                   Raw mode, for kernel developers\n"
 775 "            -d|--describe flags        Describe flags\n"
 776 "            -a|--addr    addr-spec     Walk a range of pages\n"
 777 "            -b|--bits    bits-spec     Walk pages with specified bits\n"
 778 "            -c|--cgroup  path|@inode   Walk pages within memory cgroup\n"
 779 "            -p|--pid     pid           Walk process address space\n"
 780 "            -f|--file    filename      Walk file address space\n"
 781 "            -l|--list                  Show page details in ranges\n"
 782 "            -L|--list-each             Show page details one by one\n"
 783 "            -C|--list-cgroup           Show cgroup inode for pages\n"
 784 "            -N|--no-summary            Don't show summary info\n"
 785 "            -X|--hwpoison              hwpoison pages\n"
 786 "            -x|--unpoison              unpoison pages\n"
 787 "            -h|--help                  Show this usage message\n"
 788 "flags:\n"
 789 "            0x10                       bitfield format, e.g.\n"
 790 "            anon                       bit-name, e.g.\n"
 791 "            0x10,anon                  comma-separated list, e.g.\n"
 792 "addr-spec:\n"
 793 "            N                          one page at offset N (unit: pages)\n"
 794 "            N+M                        pages range from N to N+M-1\n"
 795 "            N,M                        pages range from N to M-1\n"
 796 "            N,                         pages range from N to end\n"
 797 "            ,M                         pages range from 0 to M-1\n"
 798 "bits-spec:\n"
 799 "            bit1,bit2                  (flags & (bit1|bit2)) != 0\n"
 800 "            bit1,bit2=bit1             (flags & (bit1|bit2)) == bit1\n"
 801 "            bit1,~bit2                 (flags & (bit1|bit2)) == bit1\n"
 802 "            =bit1,bit2                 flags == (bit1|bit2)\n"
 803 "bit-names:\n"
 804         );
 805
 806         for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
 807                 if (!page_flag_names[i])
 808                         continue;
 809                 printf("%16s%s", page_flag_names[i] + 2,
 810                                  page_flag_type(1ULL << i));
 811                 if (++j > 3) {
 812                         j = 0;
 813                         putchar('\n');
 814                 }
 815         }
 816         printf("\n                                   "
 817                 "(r) raw mode bits  (o) overloaded bits\n");
 818 }
 819
 820 static unsigned long long parse_number(const char *str)
 821 {
 822         unsigned long long n;
 823
 824         n = strtoll(str, NULL, 0);
 825
 826         if (n == 0 && str[0] != '0')
 827                 fatal("invalid name or number: %s\n", str);
 828
 829         return n;
 830 }
 831
 832 static void parse_pid(const char *str)
 833 {
 834         FILE *file;
 835         char buf[5000];
 836
 837         opt_pid = parse_number(str);
 838
 839         sprintf(buf, "/proc/%d/pagemap", opt_pid);
 840         pagemap_fd = checked_open(buf, O_RDONLY);
 841
 842         sprintf(buf, "/proc/%d/maps", opt_pid);
 843         file = fopen(buf, "r");
 844         if (!file) {
 845                 perror(buf);
 846                 exit(EXIT_FAILURE);
 847         }
 848
 849         while (fgets(buf, sizeof(buf), file) != NULL) {
 850                 unsigned long vm_start;
 851                 unsigned long vm_end;
 852                 unsigned long long pgoff;
 853                 int major, minor;
 854                 char r, w, x, s;
 855                 unsigned long ino;
 856                 int n;
 857
 858                 n = sscanf(buf, "%lx-%lx %c%c%c%c %llx %x:%x %lu",
 859                            &vm_start,
 860                            &vm_end,
 861                            &r, &w, &x, &s,
 862                            &pgoff,
 863                            &major, &minor,
 864                            &ino);
 865                 if (n < 10) {
 866                         fprintf(stderr, "unexpected line: %s\n", buf);
 867                         continue;
 868                 }
 869                 pg_start[nr_vmas] = vm_start / page_size;
 870                 pg_end[nr_vmas] = vm_end / page_size;
 871                 if (++nr_vmas >= MAX_VMAS) {
 872                         fprintf(stderr, "too many VMAs\n");
 873                         break;
 874                 }
 875         }
 876         fclose(file);
 877 }
 878
 879 static void show_file(const char *name, const struct stat *st)
 880 {
 881         unsigned long long size = st->st_size;
 882         char atime[64], mtime[64];
 883         long now = time(NULL);
 884
 885         printf("%s\tInode: %u\tSize: %llu (%llu pages)\n",
 886                         name, (unsigned)st->st_ino,
 887                         size, (size + page_size - 1) / page_size);
 888
 889         strftime(atime, sizeof(atime), "%c", localtime(&st->st_atime));
 890         strftime(mtime, sizeof(mtime), "%c", localtime(&st->st_mtime));
 891
 892         printf("Modify: %s (%ld seconds ago)\nAccess: %s (%ld seconds ago)\n",
 893                         mtime, now - st->st_mtime,
 894                         atime, now - st->st_atime);
 895 }
 896
 897 static sigjmp_buf sigbus_jmp;
 898
 899 static void * volatile sigbus_addr;
 900
 901 static void sigbus_handler(int sig, siginfo_t *info, void *ucontex)
 902 {
 903         (void)sig;
 904         (void)ucontex;
 905         sigbus_addr = info ? info->si_addr : NULL;
 906         siglongjmp(sigbus_jmp, 1);
 907 }
 908
 909 static struct sigaction sigbus_action = {
 910         .sa_sigaction = sigbus_handler,
 911         .sa_flags = SA_SIGINFO,
 912 };
 913
 914 static void walk_file(const char *name, const struct stat *st)
 915 {
 916         uint8_t vec[PAGEMAP_BATCH];
 917         uint64_t buf[PAGEMAP_BATCH], flags;
 918         uint64_t cgroup = 0;
 919         unsigned long nr_pages, pfn, i;
 920         off_t off, end = st->st_size;
 921         int fd;
 922         ssize_t len;
 923         void *ptr;
 924         int first = 1;
 925
 926         fd = checked_open(name, O_RDONLY|O_NOATIME|O_NOFOLLOW);
 927
 928         for (off = 0; off < end; off += len) {
 929                 nr_pages = (end - off + page_size - 1) / page_size;
 930                 if (nr_pages > PAGEMAP_BATCH)
 931                         nr_pages = PAGEMAP_BATCH;
 932                 len = nr_pages * page_size;
 933
 934                 ptr = mmap(NULL, len, PROT_READ, MAP_SHARED, fd, off);
 935                 if (ptr == MAP_FAILED)
 936                         fatal("mmap failed: %s", name);
 937
 938                 /* determine cached pages */
 939                 if (mincore(ptr, len, vec))
 940                         fatal("mincore failed: %s", name);
 941
 942                 /* turn off readahead */
 943                 if (madvise(ptr, len, MADV_RANDOM))
 944                         fatal("madvice failed: %s", name);
 945
 946                 if (sigsetjmp(sigbus_jmp, 1)) {
 947                         end = off + sigbus_addr ? sigbus_addr - ptr : 0;
 948                         fprintf(stderr, "got sigbus at offset %lld: %s\n",
 949                                         (long long)end, name);
 950                         goto got_sigbus;
 951                 }
 952
 953                 /* populate ptes */
 954                 for (i = 0; i < nr_pages ; i++) {
 955                         if (vec[i] & 1)
 956                                 (void)*(volatile int *)(ptr + i * page_size);
 957                 }
 958 got_sigbus:
 959
 960                 /* turn off harvesting reference bits */
 961                 if (madvise(ptr, len, MADV_SEQUENTIAL))
 962                         fatal("madvice failed: %s", name);
 963
 964                 if (pagemap_read(buf, (unsigned long)ptr / page_size,
 965                                         nr_pages) != nr_pages)
 966                         fatal("cannot read pagemap");
 967
 968                 munmap(ptr, len);
 969
 970                 for (i = 0; i < nr_pages; i++) {
 971                         pfn = pagemap_pfn(buf[i]);
 972                         if (!pfn)
 973                                 continue;
 974                         if (!kpageflags_read(&flags, pfn, 1))
 975                                 continue;
 976                         if (!kpagecgroup_read(&cgroup, pfn, 1))
 977                                 fatal("kpagecgroup_read failed");
 978                         if (first && opt_list) {
 979                                 first = 0;
 980                                 flush_page_range();
 981                                 show_file(name, st);
 982                         }
 983                         add_page(off / page_size + i, pfn,
 984                                  flags, cgroup, buf[i]);
 985                 }
 986         }
 987
 988         close(fd);
 989 }
 990
 991 int walk_tree(const char *name, const struct stat *st, int type, struct FTW *f)
 992 {
 993         (void)f;
 994         switch (type) {
 995         case FTW_F:
 996                 if (S_ISREG(st->st_mode))
 997                         walk_file(name, st);
 998                 break;
 999         case FTW_DNR:
1000                 fprintf(stderr, "cannot read dir: %s\n", name);
1001                 break;
1002         }
1003         return 0;
1004 }
1005
1006 static void walk_page_cache(void)
1007 {
1008         struct stat st;
1009
1010         kpageflags_fd = checked_open(PROC_KPAGEFLAGS, O_RDONLY);
1011         pagemap_fd = checked_open("/proc/self/pagemap", O_RDONLY);
1012         sigaction(SIGBUS, &sigbus_action, NULL);
1013
1014         if (stat(opt_file, &st))
1015                 fatal("stat failed: %s\n", opt_file);
1016
1017         if (S_ISREG(st.st_mode)) {
1018                 walk_file(opt_file, &st);
1019         } else if (S_ISDIR(st.st_mode)) {
1020                 /* do not follow symlinks and mountpoints */
1021                 if (nftw(opt_file, walk_tree, 64, FTW_MOUNT | FTW_PHYS) < 0)
1022                         fatal("nftw failed: %s\n", opt_file);
1023         } else
1024                 fatal("unhandled file type: %s\n", opt_file);
1025
1026         close(kpageflags_fd);
1027         close(pagemap_fd);
1028         signal(SIGBUS, SIG_DFL);
1029 }
1030
1031 static void parse_file(const char *name)
1032 {
1033         opt_file = name;
1034 }
1035
1036 static void parse_cgroup(const char *path)
1037 {
1038         if (path[0] == '@') {
1039                 opt_cgroup = parse_number(path + 1);
1040                 return;
1041         }
1042
1043         struct stat st;
1044
1045         if (stat(path, &st))
1046                 fatal("stat failed: %s: %m\n", path);
1047
1048         if (!S_ISDIR(st.st_mode))
1049                 fatal("cgroup supposed to be a directory: %s\n", path);
1050
1051         opt_cgroup = st.st_ino;
1052 }
1053
1054 static void parse_addr_range(const char *optarg)
1055 {
1056         unsigned long offset;
1057         unsigned long size;
1058         char *p;
1059
1060         p = strchr(optarg, ',');
1061         if (!p)
1062                 p = strchr(optarg, '+');
1063
1064         if (p == optarg) {
1065                 offset = 0;
1066                 size   = parse_number(p + 1);
1067         } else if (p) {
1068                 offset = parse_number(optarg);
1069                 if (p[1] == '\0')
1070                         size = ULONG_MAX;
1071                 else {
1072                         size = parse_number(p + 1);
1073                         if (*p == ',') {
1074                                 if (size < offset)
1075                                         fatal("invalid range: %lu,%lu\n",
1076                                                         offset, size);
1077                                 size -= offset;
1078                         }
1079                 }
1080         } else {
1081                 offset = parse_number(optarg);
1082                 size   = 1;
1083         }
1084
1085         add_addr_range(offset, size);
1086 }
1087
1088 static void add_bits_filter(uint64_t mask, uint64_t bits)
1089 {
1090         if (nr_bit_filters >= MAX_BIT_FILTERS)
1091                 fatal("too much bit filters\n");
1092
1093         opt_mask[nr_bit_filters] = mask;
1094         opt_bits[nr_bit_filters] = bits;
1095         nr_bit_filters++;
1096 }
1097
1098 static uint64_t parse_flag_name(const char *str, int len)
1099 {
1100         size_t i;
1101
1102         if (!*str || !len)
1103                 return 0;
1104
1105         if (len <= 8 && !strncmp(str, "compound", len))
1106                 return BITS_COMPOUND;
1107
1108         for (i = 0; i < ARRAY_SIZE(page_flag_names); i++) {
1109                 if (!page_flag_names[i])
1110                         continue;
1111                 if (!strncmp(str, page_flag_names[i] + 2, len))
1112                         return 1ULL << i;
1113         }
1114
1115         return parse_number(str);
1116 }
1117
1118 static uint64_t parse_flag_names(const char *str, int all)
1119 {
1120         const char *p    = str;
1121         uint64_t   flags = 0;
1122
1123         while (1) {
1124                 if (*p == ',' || *p == '=' || *p == '\0') {
1125                         if ((*str != '~') || (*str == '~' && all && *++str))
1126                                 flags |= parse_flag_name(str, p - str);
1127                         if (*p != ',')
1128                                 break;
1129                         str = p + 1;
1130                 }
1131                 p++;
1132         }
1133
1134         return flags;
1135 }
1136
1137 static void parse_bits_mask(const char *optarg)
1138 {
1139         uint64_t mask;
1140         uint64_t bits;
1141         const char *p;
1142
1143         p = strchr(optarg, '=');
1144         if (p == optarg) {
1145                 mask = KPF_ALL_BITS;
1146                 bits = parse_flag_names(p + 1, 0);
1147         } else if (p) {
1148                 mask = parse_flag_names(optarg, 0);
1149                 bits = parse_flag_names(p + 1, 0);
1150         } else if (strchr(optarg, '~')) {
1151                 mask = parse_flag_names(optarg, 1);
1152                 bits = parse_flag_names(optarg, 0);
1153         } else {
1154                 mask = parse_flag_names(optarg, 0);
1155                 bits = KPF_ALL_BITS;
1156         }
1157
1158         add_bits_filter(mask, bits);
1159 }
1160
1161 static void describe_flags(const char *optarg)
1162 {
1163         uint64_t flags = parse_flag_names(optarg, 0);
1164
1165         printf("0x%016llx\t%s\t%s\n",
1166                 (unsigned long long)flags,
1167                 page_flag_name(flags),
1168                 page_flag_longname(flags));
1169 }
1170
1171 static const struct option opts[] = {
1172         { "raw"       , 0, NULL, 'r' },
1173         { "pid"       , 1, NULL, 'p' },
1174         { "file"      , 1, NULL, 'f' },
1175         { "addr"      , 1, NULL, 'a' },
1176         { "bits"      , 1, NULL, 'b' },
1177         { "cgroup"    , 1, NULL, 'c' },
1178         { "describe"  , 1, NULL, 'd' },
1179         { "list"      , 0, NULL, 'l' },
1180         { "list-each" , 0, NULL, 'L' },
1181         { "list-cgroup", 0, NULL, 'C' },
1182         { "no-summary", 0, NULL, 'N' },
1183         { "hwpoison"  , 0, NULL, 'X' },
1184         { "unpoison"  , 0, NULL, 'x' },
1185         { "help"      , 0, NULL, 'h' },
1186         { NULL        , 0, NULL, 0 }
1187 };
1188
1189 int main(int argc, char *argv[])
1190 {
1191         int c;
1192
1193         page_size = getpagesize();
1194
1195         while ((c = getopt_long(argc, argv,
1196                                 "rp:f:a:b:d:c:ClLNXxh", opts, NULL)) != -1) {
1197                 switch (c) {
1198                 case 'r':
1199                         opt_raw = 1;
1200                         break;
1201                 case 'p':
1202                         parse_pid(optarg);
1203                         break;
1204                 case 'f':
1205                         parse_file(optarg);
1206                         break;
1207                 case 'a':
1208                         parse_addr_range(optarg);
1209                         break;
1210                 case 'b':
1211                         parse_bits_mask(optarg);
1212                         break;
1213                 case 'c':
1214                         parse_cgroup(optarg);
1215                         break;
1216                 case 'C':
1217                         opt_list_cgroup = 1;
1218                         break;
1219                 case 'd':
1220                         describe_flags(optarg);
1221                         exit(0);
1222                 case 'l':
1223                         opt_list = 1;
1224                         break;
1225                 case 'L':
1226                         opt_list = 2;
1227                         break;
1228                 case 'N':
1229                         opt_no_summary = 1;
1230                         break;
1231                 case 'X':
1232                         opt_hwpoison = 1;
1233                         prepare_hwpoison_fd();
1234                         break;
1235                 case 'x':
1236                         opt_unpoison = 1;
1237                         prepare_hwpoison_fd();
1238                         break;
1239                 case 'h':
1240                         usage();
1241                         exit(0);
1242                 default:
1243                         usage();
1244                         exit(1);
1245                 }
1246         }
1247
1248         if (opt_cgroup || opt_list_cgroup)
1249                 kpagecgroup_fd = checked_open(PROC_KPAGECGROUP, O_RDONLY);
1250
1251         if (opt_list && opt_pid)
1252                 printf("voffset\t");
1253         if (opt_list && opt_file)
1254                 printf("foffset\t");
1255         if (opt_list && opt_list_cgroup)
1256                 printf("cgroup\t");
1257         if (opt_list == 1)
1258                 printf("offset\tlen\tflags\n");
1259         if (opt_list == 2)
1260                 printf("offset\tflags\n");
1261
1262         if (opt_file)
1263                 walk_page_cache();
1264         else
1265                 walk_addr_ranges();
1266
1267         if (opt_list == 1)
1268                 flush_page_range();
1269
1270         if (opt_no_summary)
1271                 return 0;
1272
1273         if (opt_list)
1274                 printf("\n\n");
1275
1276         show_summary();
1277
1278         return 0;
1279 }