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