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 _LARGEFILE64_SOURCE
  23#include <stdio.h>
  24#include <stdlib.h>
  25#include <unistd.h>
  26#include <stdint.h>
  27#include <stdarg.h>
  28#include <string.h>
  29#include <getopt.h>
  30#include <limits.h>
  31#include <assert.h>
  32#include <sys/types.h>
  33#include <sys/errno.h>
  34#include <sys/fcntl.h>
  35#include <sys/mount.h>
  36#include <sys/statfs.h>
  37#include "../../include/uapi/linux/magic.h"
  38#include "../../include/uapi/linux/kernel-page-flags.h"
  39
  40
  41#ifndef MAX_PATH
  42# define MAX_PATH 256
  43#endif
  44
  45#ifndef STR
  46# define _STR(x) #x
  47# define STR(x) _STR(x)
  48#endif
  49
  50/*
  51 * pagemap kernel ABI bits
  52 */
  53
  54#define PM_ENTRY_BYTES      sizeof(uint64_t)
  55#define PM_STATUS_BITS      3
  56#define PM_STATUS_OFFSET    (64 - PM_STATUS_BITS)
  57#define PM_STATUS_MASK      (((1LL << PM_STATUS_BITS) - 1) << PM_STATUS_OFFSET)
  58#define PM_STATUS(nr)       (((nr) << PM_STATUS_OFFSET) & PM_STATUS_MASK)
  59#define PM_PSHIFT_BITS      6
  60#define PM_PSHIFT_OFFSET    (PM_STATUS_OFFSET - PM_PSHIFT_BITS)
  61#define PM_PSHIFT_MASK      (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET)
  62#define PM_PSHIFT(x)        (((u64) (x) << PM_PSHIFT_OFFSET) & PM_PSHIFT_MASK)
  63#define PM_PFRAME_MASK      ((1LL << PM_PSHIFT_OFFSET) - 1)
  64#define PM_PFRAME(x)        ((x) & PM_PFRAME_MASK)
  65
  66#define PM_PRESENT          PM_STATUS(4LL)
  67#define PM_SWAP             PM_STATUS(2LL)
  68
  69
  70/*
  71 * kernel page flags
  72 */
  73
  74#define KPF_BYTES               8
  75#define PROC_KPAGEFLAGS         "/proc/kpageflags"
  76
  77/* [32-] kernel hacking assistances */
  78#define KPF_RESERVED            32
  79#define KPF_MLOCKED             33
  80#define KPF_MAPPEDTODISK        34
  81#define KPF_PRIVATE             35
  82#define KPF_PRIVATE_2           36
  83#define KPF_OWNER_PRIVATE       37
  84#define KPF_ARCH                38
  85#define KPF_UNCACHED            39
  86
  87/* [48-] take some arbitrary free slots for expanding overloaded flags
  88 * not part of kernel API
  89 */
  90#define KPF_READAHEAD           48
  91#define KPF_SLOB_FREE           49
  92#define KPF_SLUB_FROZEN         50
  93#define KPF_SLUB_DEBUG          51
  94
  95#define KPF_ALL_BITS            ((uint64_t)~0ULL)
  96#define KPF_HACKERS_BITS        (0xffffULL << 32)
  97#define KPF_OVERLOADED_BITS     (0xffffULL << 48)
  98#define BIT(name)               (1ULL << KPF_##name)
  99#define BITS_COMPOUND           (BIT(COMPOUND_HEAD) | BIT(COMPOUND_TAIL))
 100
 101static const char * const page_flag_names[] = {
 102        [KPF_LOCKED]            = "L:locked",
 103        [KPF_ERROR]             = "E:error",
 104        [KPF_REFERENCED]        = "R:referenced",
 105        [KPF_UPTODATE]          = "U:uptodate",
 106        [KPF_DIRTY]             = "D:dirty",
 107        [KPF_LRU]               = "l:lru",
 108        [KPF_ACTIVE]            = "A:active",
 109        [KPF_SLAB]              = "S:slab",
 110        [KPF_WRITEBACK]         = "W:writeback",
 111        [KPF_RECLAIM]           = "I:reclaim",
 112        [KPF_BUDDY]             = "B:buddy",
 113
 114        [KPF_MMAP]              = "M:mmap",
 115        [KPF_ANON]              = "a:anonymous",
 116        [KPF_SWAPCACHE]         = "s:swapcache",
 117        [KPF_SWAPBACKED]        = "b:swapbacked",
 118        [KPF_COMPOUND_HEAD]     = "H:compound_head",
 119        [KPF_COMPOUND_TAIL]     = "T:compound_tail",
 120        [KPF_HUGE]              = "G:huge",
 121        [KPF_UNEVICTABLE]       = "u:unevictable",
 122        [KPF_HWPOISON]          = "X:hwpoison",
 123        [KPF_NOPAGE]            = "n:nopage",
 124        [KPF_KSM]               = "x:ksm",
 125        [KPF_THP]               = "t:thp",
 126
 127        [KPF_RESERVED]          = "r:reserved",
 128        [KPF_MLOCKED]           = "m:mlocked",
 129        [KPF_MAPPEDTODISK]      = "d:mappedtodisk",
 130        [KPF_PRIVATE]           = "P:private",
 131        [KPF_PRIVATE_2]         = "p:private_2",
 132        [KPF_OWNER_PRIVATE]     = "O:owner_private",
 133        [KPF_ARCH]              = "h:arch",
 134        [KPF_UNCACHED]          = "c:uncached",
 135
 136        [KPF_READAHEAD]         = "I:readahead",
 137        [KPF_SLOB_FREE]         = "P:slob_free",
 138        [KPF_SLUB_FROZEN]       = "A:slub_frozen",
 139        [KPF_SLUB_DEBUG]        = "E:slub_debug",
 140};
 141
 142
 143static const char * const debugfs_known_mountpoints[] = {
 144        "/sys/kernel/debug",
 145        "/debug",
 146        0,
 147};
 148
 149/*
 150 * data structures
 151 */
 152
 153static int              opt_raw;        /* for kernel developers */
 154static int              opt_list;       /* list pages (in ranges) */
 155static int              opt_no_summary; /* don't show summary */
 156static pid_t            opt_pid;        /* process to walk */
 157
 158#define MAX_ADDR_RANGES 1024
 159static int              nr_addr_ranges;
 160static unsigned long    opt_offset[MAX_ADDR_RANGES];
 161static unsigned long    opt_size[MAX_ADDR_RANGES];
 162
 163#define MAX_VMAS        10240
 164static int              nr_vmas;
 165static unsigned long    pg_start[MAX_VMAS];
 166static unsigned long    pg_end[MAX_VMAS];
 167
 168#define MAX_BIT_FILTERS 64
 169static int              nr_bit_filters;
 170static uint64_t         opt_mask[MAX_BIT_FILTERS];
 171static uint64_t         opt_bits[MAX_BIT_FILTERS];
 172
 173static int              page_size;
 174
 175static int              pagemap_fd;
 176static int              kpageflags_fd;
 177
 178static int              opt_hwpoison;
 179static int              opt_unpoison;
 180
 181static char             hwpoison_debug_fs[MAX_PATH+1];
 182static int              hwpoison_inject_fd;
 183static int              hwpoison_forget_fd;
 184
 185#define HASH_SHIFT      13
 186#define HASH_SIZE       (1 << HASH_SHIFT)
 187#define HASH_MASK       (HASH_SIZE - 1)
 188#define HASH_KEY(flags) (flags & HASH_MASK)
 189
 190static unsigned long    total_pages;
 191static unsigned long    nr_pages[HASH_SIZE];
 192static uint64_t         page_flags[HASH_SIZE];
 193
 194
 195/*
 196 * helper functions
 197 */
 198
 199#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
 200
 201#define min_t(type, x, y) ({                    \
 202        type __min1 = (x);                      \
 203        type __min2 = (y);                      \
 204        __min1 < __min2 ? __min1 : __min2; })
 205
 206#define max_t(type, x, y) ({                    \
 207        type __max1 = (x);                      \
 208        type __max2 = (y);                      \
 209        __max1 > __max2 ? __max1 : __max2; })
 210
 211static unsigned long pages2mb(unsigned long pages)
 212{
 213        return (pages * page_size) >> 20;
 214}
 215
 216static void fatal(const char *x, ...)
 217{
 218        va_list ap;
 219
 220        va_start(ap, x);
 221        vfprintf(stderr, x, ap);
 222        va_end(ap);
 223        exit(EXIT_FAILURE);
 224}
 225
 226static int checked_open(const char *pathname, int flags)
 227{
 228        int fd = open(pathname, flags);
 229
 230        if (fd < 0) {
 231                perror(pathname);
 232                exit(EXIT_FAILURE);
 233        }
 234
 235        return fd;
 236}
 237
 238/*
 239 * pagemap/kpageflags routines
 240 */
 241
 242static unsigned long do_u64_read(int fd, char *name,
 243                                 uint64_t *buf,
 244                                 unsigned long index,
 245                                 unsigned long count)
 246{
 247        long bytes;
 248
 249        if (index > ULONG_MAX / 8)
 250                fatal("index overflow: %lu\n", index);
 251
 252        if (lseek(fd, index * 8, SEEK_SET) < 0) {
 253                perror(name);
 254                exit(EXIT_FAILURE);
 255        }
 256
 257        bytes = read(fd, buf, count * 8);
 258        if (bytes < 0) {
 259                perror(name);
 260                exit(EXIT_FAILURE);
 261        }
 262        if (bytes % 8)
 263                fatal("partial read: %lu bytes\n", bytes);
 264
 265        return bytes / 8;
 266}
 267
 268static unsigned long kpageflags_read(uint64_t *buf,
 269                                     unsigned long index,
 270                                     unsigned long pages)
 271{
 272        return do_u64_read(kpageflags_fd, PROC_KPAGEFLAGS, buf, index, pages);
 273}
 274
 275static unsigned long pagemap_read(uint64_t *buf,
 276                                  unsigned long index,
 277                                  unsigned long pages)
 278{
 279        return do_u64_read(pagemap_fd, "/proc/pid/pagemap", buf, index, pages);
 280}
 281
 282static unsigned long pagemap_pfn(uint64_t val)
 283{
 284        unsigned long pfn;
 285
 286        if (val & PM_PRESENT)
 287                pfn = PM_PFRAME(val);
 288        else
 289                pfn = 0;
 290
 291        return pfn;
 292}
 293
 294
 295/*
 296 * page flag names
 297 */
 298
 299static char *page_flag_name(uint64_t flags)
 300{
 301        static char buf[65];
 302        int present;
 303        size_t i, j;
 304
 305        for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
 306                present = (flags >> i) & 1;
 307                if (!page_flag_names[i]) {
 308                        if (present)
 309                                fatal("unknown flag bit %d\n", i);
 310                        continue;
 311                }
 312                buf[j++] = present ? page_flag_names[i][0] : '_';
 313        }
 314
 315        return buf;
 316}
 317
 318static char *page_flag_longname(uint64_t flags)
 319{
 320        static char buf[1024];
 321        size_t i, n;
 322
 323        for (i = 0, n = 0; i < ARRAY_SIZE(page_flag_names); i++) {
 324                if (!page_flag_names[i])
 325                        continue;
 326                if ((flags >> i) & 1)
 327                        n += snprintf(buf + n, sizeof(buf) - n, "%s,",
 328                                        page_flag_names[i] + 2);
 329        }
 330        if (n)
 331                n--;
 332        buf[n] = '\0';
 333
 334        return buf;
 335}
 336
 337
 338/*
 339 * page list and summary
 340 */
 341
 342static void show_page_range(unsigned long voffset,
 343                            unsigned long offset, uint64_t flags)
 344{
 345        static uint64_t      flags0;
 346        static unsigned long voff;
 347        static unsigned long index;
 348        static unsigned long count;
 349
 350        if (flags == flags0 && offset == index + count &&
 351            (!opt_pid || voffset == voff + count)) {
 352                count++;
 353                return;
 354        }
 355
 356        if (count) {
 357                if (opt_pid)
 358                        printf("%lx\t", voff);
 359                printf("%lx\t%lx\t%s\n",
 360                                index, count, page_flag_name(flags0));
 361        }
 362
 363        flags0 = flags;
 364        index  = offset;
 365        voff   = voffset;
 366        count  = 1;
 367}
 368
 369static void show_page(unsigned long voffset,
 370                      unsigned long offset, uint64_t flags)
 371{
 372        if (opt_pid)
 373                printf("%lx\t", voffset);
 374        printf("%lx\t%s\n", offset, page_flag_name(flags));
 375}
 376
 377static void show_summary(void)
 378{
 379        size_t i;
 380
 381        printf("             flags\tpage-count       MB"
 382                "  symbolic-flags\t\t\tlong-symbolic-flags\n");
 383
 384        for (i = 0; i < ARRAY_SIZE(nr_pages); i++) {
 385                if (nr_pages[i])
 386                        printf("0x%016llx\t%10lu %8lu  %s\t%s\n",
 387                                (unsigned long long)page_flags[i],
 388                                nr_pages[i],
 389                                pages2mb(nr_pages[i]),
 390                                page_flag_name(page_flags[i]),
 391                                page_flag_longname(page_flags[i]));
 392        }
 393
 394        printf("             total\t%10lu %8lu\n",
 395                        total_pages, pages2mb(total_pages));
 396}
 397
 398
 399/*
 400 * page flag filters
 401 */
 402
 403static int bit_mask_ok(uint64_t flags)
 404{
 405        int i;
 406
 407        for (i = 0; i < nr_bit_filters; i++) {
 408                if (opt_bits[i] == KPF_ALL_BITS) {
 409                        if ((flags & opt_mask[i]) == 0)
 410                                return 0;
 411                } else {
 412                        if ((flags & opt_mask[i]) != opt_bits[i])
 413                                return 0;
 414                }
 415        }
 416
 417        return 1;
 418}
 419
 420static uint64_t expand_overloaded_flags(uint64_t flags)
 421{
 422        /* SLOB/SLUB overload several page flags */
 423        if (flags & BIT(SLAB)) {
 424                if (flags & BIT(PRIVATE))
 425                        flags ^= BIT(PRIVATE) | BIT(SLOB_FREE);
 426                if (flags & BIT(ACTIVE))
 427                        flags ^= BIT(ACTIVE) | BIT(SLUB_FROZEN);
 428                if (flags & BIT(ERROR))
 429                        flags ^= BIT(ERROR) | BIT(SLUB_DEBUG);
 430        }
 431
 432        /* PG_reclaim is overloaded as PG_readahead in the read path */
 433        if ((flags & (BIT(RECLAIM) | BIT(WRITEBACK))) == BIT(RECLAIM))
 434                flags ^= BIT(RECLAIM) | BIT(READAHEAD);
 435
 436        return flags;
 437}
 438
 439static uint64_t well_known_flags(uint64_t flags)
 440{
 441        /* hide flags intended only for kernel hacker */
 442        flags &= ~KPF_HACKERS_BITS;
 443
 444        /* hide non-hugeTLB compound pages */
 445        if ((flags & BITS_COMPOUND) && !(flags & BIT(HUGE)))
 446                flags &= ~BITS_COMPOUND;
 447
 448        return flags;
 449}
 450
 451static uint64_t kpageflags_flags(uint64_t flags)
 452{
 453        flags = expand_overloaded_flags(flags);
 454
 455        if (!opt_raw)
 456                flags = well_known_flags(flags);
 457
 458        return flags;
 459}
 460
 461/* verify that a mountpoint is actually a debugfs instance */
 462static int debugfs_valid_mountpoint(const char *debugfs)
 463{
 464        struct statfs st_fs;
 465
 466        if (statfs(debugfs, &st_fs) < 0)
 467                return -ENOENT;
 468        else if (st_fs.f_type != (long) DEBUGFS_MAGIC)
 469                return -ENOENT;
 470
 471        return 0;
 472}
 473
 474/* find the path to the mounted debugfs */
 475static const char *debugfs_find_mountpoint(void)
 476{
 477        const char *const *ptr;
 478        char type[100];
 479        FILE *fp;
 480
 481        ptr = debugfs_known_mountpoints;
 482        while (*ptr) {
 483                if (debugfs_valid_mountpoint(*ptr) == 0) {
 484                        strcpy(hwpoison_debug_fs, *ptr);
 485                        return hwpoison_debug_fs;
 486                }
 487                ptr++;
 488        }
 489
 490        /* give up and parse /proc/mounts */
 491        fp = fopen("/proc/mounts", "r");
 492        if (fp == NULL)
 493                perror("Can't open /proc/mounts for read");
 494
 495        while (fscanf(fp, "%*s %"
 496                      STR(MAX_PATH)
 497                      "s %99s %*s %*d %*d\n",
 498                      hwpoison_debug_fs, type) == 2) {
 499                if (strcmp(type, "debugfs") == 0)
 500                        break;
 501        }
 502        fclose(fp);
 503
 504        if (strcmp(type, "debugfs") != 0)
 505                return NULL;
 506
 507        return hwpoison_debug_fs;
 508}
 509
 510/* mount the debugfs somewhere if it's not mounted */
 511
 512static void debugfs_mount(void)
 513{
 514        const char *const *ptr;
 515
 516        /* see if it's already mounted */
 517        if (debugfs_find_mountpoint())
 518                return;
 519
 520        ptr = debugfs_known_mountpoints;
 521        while (*ptr) {
 522                if (mount(NULL, *ptr, "debugfs", 0, NULL) == 0) {
 523                        /* save the mountpoint */
 524                        strcpy(hwpoison_debug_fs, *ptr);
 525                        break;
 526                }
 527                ptr++;
 528        }
 529
 530        if (*ptr == NULL) {
 531                perror("mount debugfs");
 532                exit(EXIT_FAILURE);
 533        }
 534}
 535
 536/*
 537 * page actions
 538 */
 539
 540static void prepare_hwpoison_fd(void)
 541{
 542        char buf[MAX_PATH + 1];
 543
 544        debugfs_mount();
 545
 546        if (opt_hwpoison && !hwpoison_inject_fd) {
 547                snprintf(buf, MAX_PATH, "%s/hwpoison/corrupt-pfn",
 548                        hwpoison_debug_fs);
 549                hwpoison_inject_fd = checked_open(buf, O_WRONLY);
 550        }
 551
 552        if (opt_unpoison && !hwpoison_forget_fd) {
 553                snprintf(buf, MAX_PATH, "%s/hwpoison/unpoison-pfn",
 554                        hwpoison_debug_fs);
 555                hwpoison_forget_fd = checked_open(buf, O_WRONLY);
 556        }
 557}
 558
 559static int hwpoison_page(unsigned long offset)
 560{
 561        char buf[100];
 562        int len;
 563
 564        len = sprintf(buf, "0x%lx\n", offset);
 565        len = write(hwpoison_inject_fd, buf, len);
 566        if (len < 0) {
 567                perror("hwpoison inject");
 568                return len;
 569        }
 570        return 0;
 571}
 572
 573static int unpoison_page(unsigned long offset)
 574{
 575        char buf[100];
 576        int len;
 577
 578        len = sprintf(buf, "0x%lx\n", offset);
 579        len = write(hwpoison_forget_fd, buf, len);
 580        if (len < 0) {
 581                perror("hwpoison forget");
 582                return len;
 583        }
 584        return 0;
 585}
 586
 587/*
 588 * page frame walker
 589 */
 590
 591static size_t hash_slot(uint64_t flags)
 592{
 593        size_t k = HASH_KEY(flags);
 594        size_t i;
 595
 596        /* Explicitly reserve slot 0 for flags 0: the following logic
 597         * cannot distinguish an unoccupied slot from slot (flags==0).
 598         */
 599        if (flags == 0)
 600                return 0;
 601
 602        /* search through the remaining (HASH_SIZE-1) slots */
 603        for (i = 1; i < ARRAY_SIZE(page_flags); i++, k++) {
 604                if (!k || k >= ARRAY_SIZE(page_flags))
 605                        k = 1;
 606                if (page_flags[k] == 0) {
 607                        page_flags[k] = flags;
 608                        return k;
 609                }
 610                if (page_flags[k] == flags)
 611                        return k;
 612        }
 613
 614        fatal("hash table full: bump up HASH_SHIFT?\n");
 615        exit(EXIT_FAILURE);
 616}
 617
 618static void add_page(unsigned long voffset,
 619                     unsigned long offset, uint64_t flags)
 620{
 621        flags = kpageflags_flags(flags);
 622
 623        if (!bit_mask_ok(flags))
 624                return;
 625
 626        if (opt_hwpoison)
 627                hwpoison_page(offset);
 628        if (opt_unpoison)
 629                unpoison_page(offset);
 630
 631        if (opt_list == 1)
 632                show_page_range(voffset, offset, flags);
 633        else if (opt_list == 2)
 634                show_page(voffset, offset, flags);
 635
 636        nr_pages[hash_slot(flags)]++;
 637        total_pages++;
 638}
 639
 640#define KPAGEFLAGS_BATCH        (64 << 10)      /* 64k pages */
 641static void walk_pfn(unsigned long voffset,
 642                     unsigned long index,
 643                     unsigned long count)
 644{
 645        uint64_t buf[KPAGEFLAGS_BATCH];
 646        unsigned long batch;
 647        unsigned long pages;
 648        unsigned long i;
 649
 650        while (count) {
 651                batch = min_t(unsigned long, count, KPAGEFLAGS_BATCH);
 652                pages = kpageflags_read(buf, index, batch);
 653                if (pages == 0)
 654                        break;
 655
 656                for (i = 0; i < pages; i++)
 657                        add_page(voffset + i, index + i, buf[i]);
 658
 659                index += pages;
 660                count -= pages;
 661        }
 662}
 663
 664#define PAGEMAP_BATCH   (64 << 10)
 665static void walk_vma(unsigned long index, unsigned long count)
 666{
 667        uint64_t buf[PAGEMAP_BATCH];
 668        unsigned long batch;
 669        unsigned long pages;
 670        unsigned long pfn;
 671        unsigned long i;
 672
 673        while (count) {
 674                batch = min_t(unsigned long, count, PAGEMAP_BATCH);
 675                pages = pagemap_read(buf, index, batch);
 676                if (pages == 0)
 677                        break;
 678
 679                for (i = 0; i < pages; i++) {
 680                        pfn = pagemap_pfn(buf[i]);
 681                        if (pfn)
 682                                walk_pfn(index + i, pfn, 1);
 683                }
 684
 685                index += pages;
 686                count -= pages;
 687        }
 688}
 689
 690static void walk_task(unsigned long index, unsigned long count)
 691{
 692        const unsigned long end = index + count;
 693        unsigned long start;
 694        int i = 0;
 695
 696        while (index < end) {
 697
 698                while (pg_end[i] <= index)
 699                        if (++i >= nr_vmas)
 700                                return;
 701                if (pg_start[i] >= end)
 702                        return;
 703
 704                start = max_t(unsigned long, pg_start[i], index);
 705                index = min_t(unsigned long, pg_end[i], end);
 706
 707                assert(start < index);
 708                walk_vma(start, index - start);
 709        }
 710}
 711
 712static void add_addr_range(unsigned long offset, unsigned long size)
 713{
 714        if (nr_addr_ranges >= MAX_ADDR_RANGES)
 715                fatal("too many addr ranges\n");
 716
 717        opt_offset[nr_addr_ranges] = offset;
 718        opt_size[nr_addr_ranges] = min_t(unsigned long, size, ULONG_MAX-offset);
 719        nr_addr_ranges++;
 720}
 721
 722static void walk_addr_ranges(void)
 723{
 724        int i;
 725
 726        kpageflags_fd = checked_open(PROC_KPAGEFLAGS, O_RDONLY);
 727
 728        if (!nr_addr_ranges)
 729                add_addr_range(0, ULONG_MAX);
 730
 731        for (i = 0; i < nr_addr_ranges; i++)
 732                if (!opt_pid)
 733                        walk_pfn(0, opt_offset[i], opt_size[i]);
 734                else
 735                        walk_task(opt_offset[i], opt_size[i]);
 736
 737        close(kpageflags_fd);
 738}
 739
 740
 741/*
 742 * user interface
 743 */
 744
 745static const char *page_flag_type(uint64_t flag)
 746{
 747        if (flag & KPF_HACKERS_BITS)
 748                return "(r)";
 749        if (flag & KPF_OVERLOADED_BITS)
 750                return "(o)";
 751        return "   ";
 752}
 753
 754static void usage(void)
 755{
 756        size_t i, j;
 757
 758        printf(
 759"page-types [options]\n"
 760"            -r|--raw                   Raw mode, for kernel developers\n"
 761"            -d|--describe flags        Describe flags\n"
 762"            -a|--addr    addr-spec     Walk a range of pages\n"
 763"            -b|--bits    bits-spec     Walk pages with specified bits\n"
 764"            -p|--pid     pid           Walk process address space\n"
 765#if 0 /* planned features */
 766"            -f|--file    filename      Walk file address space\n"
 767#endif
 768"            -l|--list                  Show page details in ranges\n"
 769"            -L|--list-each             Show page details one by one\n"
 770"            -N|--no-summary            Don't show summary info\n"
 771"            -X|--hwpoison              hwpoison pages\n"
 772"            -x|--unpoison              unpoison pages\n"
 773"            -h|--help                  Show this usage message\n"
 774"flags:\n"
 775"            0x10                       bitfield format, e.g.\n"
 776"            anon                       bit-name, e.g.\n"
 777"            0x10,anon                  comma-separated list, e.g.\n"
 778"addr-spec:\n"
 779"            N                          one page at offset N (unit: pages)\n"
 780"            N+M                        pages range from N to N+M-1\n"
 781"            N,M                        pages range from N to M-1\n"
 782"            N,                         pages range from N to end\n"
 783"            ,M                         pages range from 0 to M-1\n"
 784"bits-spec:\n"
 785"            bit1,bit2                  (flags & (bit1|bit2)) != 0\n"
 786"            bit1,bit2=bit1             (flags & (bit1|bit2)) == bit1\n"
 787"            bit1,~bit2                 (flags & (bit1|bit2)) == bit1\n"
 788"            =bit1,bit2                 flags == (bit1|bit2)\n"
 789"bit-names:\n"
 790        );
 791
 792        for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
 793                if (!page_flag_names[i])
 794                        continue;
 795                printf("%16s%s", page_flag_names[i] + 2,
 796                                 page_flag_type(1ULL << i));
 797                if (++j > 3) {
 798                        j = 0;
 799                        putchar('\n');
 800                }
 801        }
 802        printf("\n                                   "
 803                "(r) raw mode bits  (o) overloaded bits\n");
 804}
 805
 806static unsigned long long parse_number(const char *str)
 807{
 808        unsigned long long n;
 809
 810        n = strtoll(str, NULL, 0);
 811
 812        if (n == 0 && str[0] != '0')
 813                fatal("invalid name or number: %s\n", str);
 814
 815        return n;
 816}
 817
 818static void parse_pid(const char *str)
 819{
 820        FILE *file;
 821        char buf[5000];
 822
 823        opt_pid = parse_number(str);
 824
 825        sprintf(buf, "/proc/%d/pagemap", opt_pid);
 826        pagemap_fd = checked_open(buf, O_RDONLY);
 827
 828        sprintf(buf, "/proc/%d/maps", opt_pid);
 829        file = fopen(buf, "r");
 830        if (!file) {
 831                perror(buf);
 832                exit(EXIT_FAILURE);
 833        }
 834
 835        while (fgets(buf, sizeof(buf), file) != NULL) {
 836                unsigned long vm_start;
 837                unsigned long vm_end;
 838                unsigned long long pgoff;
 839                int major, minor;
 840                char r, w, x, s;
 841                unsigned long ino;
 842                int n;
 843
 844                n = sscanf(buf, "%lx-%lx %c%c%c%c %llx %x:%x %lu",
 845                           &vm_start,
 846                           &vm_end,
 847                           &r, &w, &x, &s,
 848                           &pgoff,
 849                           &major, &minor,
 850                           &ino);
 851                if (n < 10) {
 852                        fprintf(stderr, "unexpected line: %s\n", buf);
 853                        continue;
 854                }
 855                pg_start[nr_vmas] = vm_start / page_size;
 856                pg_end[nr_vmas] = vm_end / page_size;
 857                if (++nr_vmas >= MAX_VMAS) {
 858                        fprintf(stderr, "too many VMAs\n");
 859                        break;
 860                }
 861        }
 862        fclose(file);
 863}
 864
 865static void parse_file(const char *name)
 866{
 867}
 868
 869static void parse_addr_range(const char *optarg)
 870{
 871        unsigned long offset;
 872        unsigned long size;
 873        char *p;
 874
 875        p = strchr(optarg, ',');
 876        if (!p)
 877                p = strchr(optarg, '+');
 878
 879        if (p == optarg) {
 880                offset = 0;
 881                size   = parse_number(p + 1);
 882        } else if (p) {
 883                offset = parse_number(optarg);
 884                if (p[1] == '\0')
 885                        size = ULONG_MAX;
 886                else {
 887                        size = parse_number(p + 1);
 888                        if (*p == ',') {
 889                                if (size < offset)
 890                                        fatal("invalid range: %lu,%lu\n",
 891                                                        offset, size);
 892                                size -= offset;
 893                        }
 894                }
 895        } else {
 896                offset = parse_number(optarg);
 897                size   = 1;
 898        }
 899
 900        add_addr_range(offset, size);
 901}
 902
 903static void add_bits_filter(uint64_t mask, uint64_t bits)
 904{
 905        if (nr_bit_filters >= MAX_BIT_FILTERS)
 906                fatal("too much bit filters\n");
 907
 908        opt_mask[nr_bit_filters] = mask;
 909        opt_bits[nr_bit_filters] = bits;
 910        nr_bit_filters++;
 911}
 912
 913static uint64_t parse_flag_name(const char *str, int len)
 914{
 915        size_t i;
 916
 917        if (!*str || !len)
 918                return 0;
 919
 920        if (len <= 8 && !strncmp(str, "compound", len))
 921                return BITS_COMPOUND;
 922
 923        for (i = 0; i < ARRAY_SIZE(page_flag_names); i++) {
 924                if (!page_flag_names[i])
 925                        continue;
 926                if (!strncmp(str, page_flag_names[i] + 2, len))
 927                        return 1ULL << i;
 928        }
 929
 930        return parse_number(str);
 931}
 932
 933static uint64_t parse_flag_names(const char *str, int all)
 934{
 935        const char *p    = str;
 936        uint64_t   flags = 0;
 937
 938        while (1) {
 939                if (*p == ',' || *p == '=' || *p == '\0') {
 940                        if ((*str != '~') || (*str == '~' && all && *++str))
 941                                flags |= parse_flag_name(str, p - str);
 942                        if (*p != ',')
 943                                break;
 944                        str = p + 1;
 945                }
 946                p++;
 947        }
 948
 949        return flags;
 950}
 951
 952static void parse_bits_mask(const char *optarg)
 953{
 954        uint64_t mask;
 955        uint64_t bits;
 956        const char *p;
 957
 958        p = strchr(optarg, '=');
 959        if (p == optarg) {
 960                mask = KPF_ALL_BITS;
 961                bits = parse_flag_names(p + 1, 0);
 962        } else if (p) {
 963                mask = parse_flag_names(optarg, 0);
 964                bits = parse_flag_names(p + 1, 0);
 965        } else if (strchr(optarg, '~')) {
 966                mask = parse_flag_names(optarg, 1);
 967                bits = parse_flag_names(optarg, 0);
 968        } else {
 969                mask = parse_flag_names(optarg, 0);
 970                bits = KPF_ALL_BITS;
 971        }
 972
 973        add_bits_filter(mask, bits);
 974}
 975
 976static void describe_flags(const char *optarg)
 977{
 978        uint64_t flags = parse_flag_names(optarg, 0);
 979
 980        printf("0x%016llx\t%s\t%s\n",
 981                (unsigned long long)flags,
 982                page_flag_name(flags),
 983                page_flag_longname(flags));
 984}
 985
 986static const struct option opts[] = {
 987        { "raw"       , 0, NULL, 'r' },
 988        { "pid"       , 1, NULL, 'p' },
 989        { "file"      , 1, NULL, 'f' },
 990        { "addr"      , 1, NULL, 'a' },
 991        { "bits"      , 1, NULL, 'b' },
 992        { "describe"  , 1, NULL, 'd' },
 993        { "list"      , 0, NULL, 'l' },
 994        { "list-each" , 0, NULL, 'L' },
 995        { "no-summary", 0, NULL, 'N' },
 996        { "hwpoison"  , 0, NULL, 'X' },
 997        { "unpoison"  , 0, NULL, 'x' },
 998        { "help"      , 0, NULL, 'h' },
 999        { NULL        , 0, NULL, 0 }
1000};
1001
1002int main(int argc, char *argv[])
1003{
1004        int c;
1005
1006        page_size = getpagesize();
1007
1008        while ((c = getopt_long(argc, argv,
1009                                "rp:f:a:b:d:lLNXxh", opts, NULL)) != -1) {
1010                switch (c) {
1011                case 'r':
1012                        opt_raw = 1;
1013                        break;
1014                case 'p':
1015                        parse_pid(optarg);
1016                        break;
1017                case 'f':
1018                        parse_file(optarg);
1019                        break;
1020                case 'a':
1021                        parse_addr_range(optarg);
1022                        break;
1023                case 'b':
1024                        parse_bits_mask(optarg);
1025                        break;
1026                case 'd':
1027                        describe_flags(optarg);
1028                        exit(0);
1029                case 'l':
1030                        opt_list = 1;
1031                        break;
1032                case 'L':
1033                        opt_list = 2;
1034                        break;
1035                case 'N':
1036                        opt_no_summary = 1;
1037                        break;
1038                case 'X':
1039                        opt_hwpoison = 1;
1040                        prepare_hwpoison_fd();
1041                        break;
1042                case 'x':
1043                        opt_unpoison = 1;
1044                        prepare_hwpoison_fd();
1045                        break;
1046                case 'h':
1047                        usage();
1048                        exit(0);
1049                default:
1050                        usage();
1051                        exit(1);
1052                }
1053        }
1054
1055        if (opt_list && opt_pid)
1056                printf("voffset\t");
1057        if (opt_list == 1)
1058                printf("offset\tlen\tflags\n");
1059        if (opt_list == 2)
1060                printf("offset\tflags\n");
1061
1062        walk_addr_ranges();
1063
1064        if (opt_list == 1)
1065                show_page_range(0, 0, 0);  /* drain the buffer */
1066
1067        if (opt_no_summary)
1068                return 0;
1069
1070        if (opt_list)
1071                printf("\n\n");
1072
1073        show_summary();
1074
1075        return 0;
1076}
1077
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.