linux/tools/vm/page-types.c
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   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
  99static 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
 154static int              opt_raw;        /* for kernel developers */
 155static int              opt_list;       /* list pages (in ranges) */
 156static int              opt_mark_idle;  /* set accessed bit */
 157static int              opt_no_summary; /* don't show summary */
 158static pid_t            opt_pid;        /* process to walk */
 159const char              *opt_file;      /* file or directory path */
 160static uint64_t         opt_cgroup;     /* cgroup inode */
 161static int              opt_list_cgroup;/* list page cgroup */
 162static int              opt_list_mapcnt;/* list page map count */
 163static const char       *opt_kpageflags;/* kpageflags file to parse */
 164
 165#define MAX_ADDR_RANGES 1024
 166static int              nr_addr_ranges;
 167static unsigned long    opt_offset[MAX_ADDR_RANGES];
 168static unsigned long    opt_size[MAX_ADDR_RANGES];
 169
 170#define MAX_VMAS        10240
 171static int              nr_vmas;
 172static unsigned long    pg_start[MAX_VMAS];
 173static unsigned long    pg_end[MAX_VMAS];
 174
 175#define MAX_BIT_FILTERS 64
 176static int              nr_bit_filters;
 177static uint64_t         opt_mask[MAX_BIT_FILTERS];
 178static uint64_t         opt_bits[MAX_BIT_FILTERS];
 179
 180static int              page_size;
 181
 182static int              pagemap_fd;
 183static int              kpageflags_fd;
 184static int              kpagecount_fd = -1;
 185static int              kpagecgroup_fd = -1;
 186static int              page_idle_fd = -1;
 187
 188static int              opt_hwpoison;
 189static int              opt_unpoison;
 190
 191static const char       *hwpoison_debug_fs;
 192static int              hwpoison_inject_fd;
 193static 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
 200static unsigned long    total_pages;
 201static unsigned long    nr_pages[HASH_SIZE];
 202static 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
 221static unsigned long pages2mb(unsigned long pages)
 222{
 223        return (pages * page_size) >> 20;
 224}
 225
 226static 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
 236static 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
 252static 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
 273static 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
 280static 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
 290static 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
 299static 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
 306static 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
 318static 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
 327static 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
 346static 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
 370static 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
 408static void flush_page_range(void)
 409{
 410        show_page_range(0, 0, 0, 0, 0, 0);
 411}
 412
 413static 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
 428static 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
 454static 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
 471static 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
 499static 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
 511static 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
 525static 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
 548static 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
 562static 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
 576static 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
 604static 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
 631static 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 */
 661static 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
 704static 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)
 725static 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
 752static 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
 774static 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
 784static 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
 810static 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
 819static 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
 874static 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
 886static 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
 933static 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
 951static sigjmp_buf sigbus_jmp;
 952
 953static void * volatile sigbus_addr;
 954
 955static 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
 963static struct sigaction sigbus_action = {
 964        .sa_sigaction = sigbus_handler,
 965        .sa_flags = SA_SIGINFO,
 966};
 967
 968static 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                }
1013got_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
1048int 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
1063static 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
1088static void parse_file(const char *name)
1089{
1090        opt_file = name;
1091}
1092
1093static 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
1111static 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
1145static 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
1155static 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
1175static 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
1194static 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
1218static void parse_kpageflags(const char *name)
1219{
1220        opt_kpageflags = name;
1221}
1222
1223static 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
1233static 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
1254int 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