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   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/linux/magic.h"
  38
  39
  40#ifndef MAX_PATH
  41# define MAX_PATH 256
  42#endif
  43
  44#ifndef STR
  45# define _STR(x) #x
  46# define STR(x) _STR(x)
  47#endif
  48
  49/*
  50 * pagemap kernel ABI bits
  51 */
  52
  53#define PM_ENTRY_BYTES      sizeof(uint64_t)
  54#define PM_STATUS_BITS      3
  55#define PM_STATUS_OFFSET    (64 - PM_STATUS_BITS)
  56#define PM_STATUS_MASK      (((1LL << PM_STATUS_BITS) - 1) << PM_STATUS_OFFSET)
  57#define PM_STATUS(nr)       (((nr) << PM_STATUS_OFFSET) & PM_STATUS_MASK)
  58#define PM_PSHIFT_BITS      6
  59#define PM_PSHIFT_OFFSET    (PM_STATUS_OFFSET - PM_PSHIFT_BITS)
  60#define PM_PSHIFT_MASK      (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET)
  61#define PM_PSHIFT(x)        (((u64) (x) << PM_PSHIFT_OFFSET) & PM_PSHIFT_MASK)
  62#define PM_PFRAME_MASK      ((1LL << PM_PSHIFT_OFFSET) - 1)
  63#define PM_PFRAME(x)        ((x) & PM_PFRAME_MASK)
  64
  65#define PM_PRESENT          PM_STATUS(4LL)
  66#define PM_SWAP             PM_STATUS(2LL)
  67
  68
  69/*
  70 * kernel page flags
  71 */
  72
  73#define KPF_BYTES		8
  74#define PROC_KPAGEFLAGS		"/proc/kpageflags"
  75
  76/* copied from kpageflags_read() */
  77#define KPF_LOCKED		0
  78#define KPF_ERROR		1
  79#define KPF_REFERENCED		2
  80#define KPF_UPTODATE		3
  81#define KPF_DIRTY		4
  82#define KPF_LRU			5
  83#define KPF_ACTIVE		6
  84#define KPF_SLAB		7
  85#define KPF_WRITEBACK		8
  86#define KPF_RECLAIM		9
  87#define KPF_BUDDY		10
  88
  89/* [11-20] new additions in 2.6.31 */
  90#define KPF_MMAP		11
  91#define KPF_ANON		12
  92#define KPF_SWAPCACHE		13
  93#define KPF_SWAPBACKED		14
  94#define KPF_COMPOUND_HEAD	15
  95#define KPF_COMPOUND_TAIL	16
  96#define KPF_HUGE		17
  97#define KPF_UNEVICTABLE		18
  98#define KPF_HWPOISON		19
  99#define KPF_NOPAGE		20
 100#define KPF_KSM			21
 101
 102/* [32-] kernel hacking assistances */
 103#define KPF_RESERVED		32
 104#define KPF_MLOCKED		33
 105#define KPF_MAPPEDTODISK	34
 106#define KPF_PRIVATE		35
 107#define KPF_PRIVATE_2		36
 108#define KPF_OWNER_PRIVATE	37
 109#define KPF_ARCH		38
 110#define KPF_UNCACHED		39
 111
 112/* [48-] take some arbitrary free slots for expanding overloaded flags
 113 * not part of kernel API
 114 */
 115#define KPF_READAHEAD		48
 116#define KPF_SLOB_FREE		49
 117#define KPF_SLUB_FROZEN		50
 118#define KPF_SLUB_DEBUG		51
 119
 120#define KPF_ALL_BITS		((uint64_t)~0ULL)
 121#define KPF_HACKERS_BITS	(0xffffULL << 32)
 122#define KPF_OVERLOADED_BITS	(0xffffULL << 48)
 123#define BIT(name)		(1ULL << KPF_##name)
 124#define BITS_COMPOUND		(BIT(COMPOUND_HEAD) | BIT(COMPOUND_TAIL))
 125
 126static const char *page_flag_names[] = {
 127	[KPF_LOCKED]		= "L:locked",
 128	[KPF_ERROR]		= "E:error",
 129	[KPF_REFERENCED]	= "R:referenced",
 130	[KPF_UPTODATE]		= "U:uptodate",
 131	[KPF_DIRTY]		= "D:dirty",
 132	[KPF_LRU]		= "l:lru",
 133	[KPF_ACTIVE]		= "A:active",
 134	[KPF_SLAB]		= "S:slab",
 135	[KPF_WRITEBACK]		= "W:writeback",
 136	[KPF_RECLAIM]		= "I:reclaim",
 137	[KPF_BUDDY]		= "B:buddy",
 138
 139	[KPF_MMAP]		= "M:mmap",
 140	[KPF_ANON]		= "a:anonymous",
 141	[KPF_SWAPCACHE]		= "s:swapcache",
 142	[KPF_SWAPBACKED]	= "b:swapbacked",
 143	[KPF_COMPOUND_HEAD]	= "H:compound_head",
 144	[KPF_COMPOUND_TAIL]	= "T:compound_tail",
 145	[KPF_HUGE]		= "G:huge",
 146	[KPF_UNEVICTABLE]	= "u:unevictable",
 147	[KPF_HWPOISON]		= "X:hwpoison",
 148	[KPF_NOPAGE]		= "n:nopage",
 149	[KPF_KSM]		= "x:ksm",
 150
 151	[KPF_RESERVED]		= "r:reserved",
 152	[KPF_MLOCKED]		= "m:mlocked",
 153	[KPF_MAPPEDTODISK]	= "d:mappedtodisk",
 154	[KPF_PRIVATE]		= "P:private",
 155	[KPF_PRIVATE_2]		= "p:private_2",
 156	[KPF_OWNER_PRIVATE]	= "O:owner_private",
 157	[KPF_ARCH]		= "h:arch",
 158	[KPF_UNCACHED]		= "c:uncached",
 159
 160	[KPF_READAHEAD]		= "I:readahead",
 161	[KPF_SLOB_FREE]		= "P:slob_free",
 162	[KPF_SLUB_FROZEN]	= "A:slub_frozen",
 163	[KPF_SLUB_DEBUG]	= "E:slub_debug",
 164};
 165
 166
 167static const char *debugfs_known_mountpoints[] = {
 168	"/sys/kernel/debug",
 169	"/debug",
 170	0,
 171};
 172
 173/*
 174 * data structures
 175 */
 176
 177static int		opt_raw;	/* for kernel developers */
 178static int		opt_list;	/* list pages (in ranges) */
 179static int		opt_no_summary;	/* don't show summary */
 180static pid_t		opt_pid;	/* process to walk */
 181
 182#define MAX_ADDR_RANGES	1024
 183static int		nr_addr_ranges;
 184static unsigned long	opt_offset[MAX_ADDR_RANGES];
 185static unsigned long	opt_size[MAX_ADDR_RANGES];
 186
 187#define MAX_VMAS	10240
 188static int		nr_vmas;
 189static unsigned long	pg_start[MAX_VMAS];
 190static unsigned long	pg_end[MAX_VMAS];
 191
 192#define MAX_BIT_FILTERS	64
 193static int		nr_bit_filters;
 194static uint64_t		opt_mask[MAX_BIT_FILTERS];
 195static uint64_t		opt_bits[MAX_BIT_FILTERS];
 196
 197static int		page_size;
 198
 199static int		pagemap_fd;
 200static int		kpageflags_fd;
 201
 202static int		opt_hwpoison;
 203static int		opt_unpoison;
 204
 205static char		hwpoison_debug_fs[MAX_PATH+1];
 206static int		hwpoison_inject_fd;
 207static int		hwpoison_forget_fd;
 208
 209#define HASH_SHIFT	13
 210#define HASH_SIZE	(1 << HASH_SHIFT)
 211#define HASH_MASK	(HASH_SIZE - 1)
 212#define HASH_KEY(flags)	(flags & HASH_MASK)
 213
 214static unsigned long	total_pages;
 215static unsigned long	nr_pages[HASH_SIZE];
 216static uint64_t 	page_flags[HASH_SIZE];
 217
 218
 219/*
 220 * helper functions
 221 */
 222
 223#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
 224
 225#define min_t(type, x, y) ({			\
 226	type __min1 = (x);			\
 227	type __min2 = (y);			\
 228	__min1 < __min2 ? __min1 : __min2; })
 229
 230#define max_t(type, x, y) ({			\
 231	type __max1 = (x);			\
 232	type __max2 = (y);			\
 233	__max1 > __max2 ? __max1 : __max2; })
 234
 235static unsigned long pages2mb(unsigned long pages)
 236{
 237	return (pages * page_size) >> 20;
 238}
 239
 240static void fatal(const char *x, ...)
 241{
 242	va_list ap;
 243
 244	va_start(ap, x);
 245	vfprintf(stderr, x, ap);
 246	va_end(ap);
 247	exit(EXIT_FAILURE);
 248}
 249
 250static int checked_open(const char *pathname, int flags)
 251{
 252	int fd = open(pathname, flags);
 253
 254	if (fd < 0) {
 255		perror(pathname);
 256		exit(EXIT_FAILURE);
 257	}
 258
 259	return fd;
 260}
 261
 262/*
 263 * pagemap/kpageflags routines
 264 */
 265
 266static unsigned long do_u64_read(int fd, char *name,
 267				 uint64_t *buf,
 268				 unsigned long index,
 269				 unsigned long count)
 270{
 271	long bytes;
 272
 273	if (index > ULONG_MAX / 8)
 274		fatal("index overflow: %lu\n", index);
 275
 276	if (lseek(fd, index * 8, SEEK_SET) < 0) {
 277		perror(name);
 278		exit(EXIT_FAILURE);
 279	}
 280
 281	bytes = read(fd, buf, count * 8);
 282	if (bytes < 0) {
 283		perror(name);
 284		exit(EXIT_FAILURE);
 285	}
 286	if (bytes % 8)
 287		fatal("partial read: %lu bytes\n", bytes);
 288
 289	return bytes / 8;
 290}
 291
 292static unsigned long kpageflags_read(uint64_t *buf,
 293				     unsigned long index,
 294				     unsigned long pages)
 295{
 296	return do_u64_read(kpageflags_fd, PROC_KPAGEFLAGS, 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
 318
 319/*
 320 * page flag names
 321 */
 322
 323static char *page_flag_name(uint64_t flags)
 324{
 325	static char buf[65];
 326	int present;
 327	int i, j;
 328
 329	for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
 330		present = (flags >> i) & 1;
 331		if (!page_flag_names[i]) {
 332			if (present)
 333				fatal("unknown flag bit %d\n", i);
 334			continue;
 335		}
 336		buf[j++] = present ? page_flag_names[i][0] : '_';
 337	}
 338
 339	return buf;
 340}
 341
 342static char *page_flag_longname(uint64_t flags)
 343{
 344	static char buf[1024];
 345	int i, n;
 346
 347	for (i = 0, n = 0; i < ARRAY_SIZE(page_flag_names); i++) {
 348		if (!page_flag_names[i])
 349			continue;
 350		if ((flags >> i) & 1)
 351			n += snprintf(buf + n, sizeof(buf) - n, "%s,",
 352					page_flag_names[i] + 2);
 353	}
 354	if (n)
 355		n--;
 356	buf[n] = '\0';
 357
 358	return buf;
 359}
 360
 361
 362/*
 363 * page list and summary
 364 */
 365
 366static void show_page_range(unsigned long voffset,
 367			    unsigned long offset, uint64_t flags)
 368{
 369	static uint64_t      flags0;
 370	static unsigned long voff;
 371	static unsigned long index;
 372	static unsigned long count;
 373
 374	if (flags == flags0 && offset == index + count &&
 375	    (!opt_pid || voffset == voff + count)) {
 376		count++;
 377		return;
 378	}
 379
 380	if (count) {
 381		if (opt_pid)
 382			printf("%lx\t", voff);
 383		printf("%lx\t%lx\t%s\n",
 384				index, count, page_flag_name(flags0));
 385	}
 386
 387	flags0 = flags;
 388	index  = offset;
 389	voff   = voffset;
 390	count  = 1;
 391}
 392
 393static void show_page(unsigned long voffset,
 394		      unsigned long offset, uint64_t flags)
 395{
 396	if (opt_pid)
 397		printf("%lx\t", voffset);
 398	printf("%lx\t%s\n", offset, page_flag_name(flags));
 399}
 400
 401static void show_summary(void)
 402{
 403	int i;
 404
 405	printf("             flags\tpage-count       MB"
 406		"  symbolic-flags\t\t\tlong-symbolic-flags\n");
 407
 408	for (i = 0; i < ARRAY_SIZE(nr_pages); i++) {
 409		if (nr_pages[i])
 410			printf("0x%016llx\t%10lu %8lu  %s\t%s\n",
 411				(unsigned long long)page_flags[i],
 412				nr_pages[i],
 413				pages2mb(nr_pages[i]),
 414				page_flag_name(page_flags[i]),
 415				page_flag_longname(page_flags[i]));
 416	}
 417
 418	printf("             total\t%10lu %8lu\n",
 419			total_pages, pages2mb(total_pages));
 420}
 421
 422
 423/*
 424 * page flag filters
 425 */
 426
 427static int bit_mask_ok(uint64_t flags)
 428{
 429	int i;
 430
 431	for (i = 0; i < nr_bit_filters; i++) {
 432		if (opt_bits[i] == KPF_ALL_BITS) {
 433			if ((flags & opt_mask[i]) == 0)
 434				return 0;
 435		} else {
 436			if ((flags & opt_mask[i]) != opt_bits[i])
 437				return 0;
 438		}
 439	}
 440
 441	return 1;
 442}
 443
 444static uint64_t expand_overloaded_flags(uint64_t flags)
 445{
 446	/* SLOB/SLUB overload several page flags */
 447	if (flags & BIT(SLAB)) {
 448		if (flags & BIT(PRIVATE))
 449			flags ^= BIT(PRIVATE) | BIT(SLOB_FREE);
 450		if (flags & BIT(ACTIVE))
 451			flags ^= BIT(ACTIVE) | BIT(SLUB_FROZEN);
 452		if (flags & BIT(ERROR))
 453			flags ^= BIT(ERROR) | BIT(SLUB_DEBUG);
 454	}
 455
 456	/* PG_reclaim is overloaded as PG_readahead in the read path */
 457	if ((flags & (BIT(RECLAIM) | BIT(WRITEBACK))) == BIT(RECLAIM))
 458		flags ^= BIT(RECLAIM) | BIT(READAHEAD);
 459
 460	return flags;
 461}
 462
 463static uint64_t well_known_flags(uint64_t flags)
 464{
 465	/* hide flags intended only for kernel hacker */
 466	flags &= ~KPF_HACKERS_BITS;
 467
 468	/* hide non-hugeTLB compound pages */
 469	if ((flags & BITS_COMPOUND) && !(flags & BIT(HUGE)))
 470		flags &= ~BITS_COMPOUND;
 471
 472	return flags;
 473}
 474
 475static uint64_t kpageflags_flags(uint64_t flags)
 476{
 477	flags = expand_overloaded_flags(flags);
 478
 479	if (!opt_raw)
 480		flags = well_known_flags(flags);
 481
 482	return flags;
 483}
 484
 485/* verify that a mountpoint is actually a debugfs instance */
 486static int debugfs_valid_mountpoint(const char *debugfs)
 487{
 488	struct statfs st_fs;
 489
 490	if (statfs(debugfs, &st_fs) < 0)
 491		return -ENOENT;
 492	else if (st_fs.f_type != (long) DEBUGFS_MAGIC)
 493		return -ENOENT;
 494
 495	return 0;
 496}
 497
 498/* find the path to the mounted debugfs */
 499static const char *debugfs_find_mountpoint(void)
 500{
 501	const char **ptr;
 502	char type[100];
 503	FILE *fp;
 504
 505	ptr = debugfs_known_mountpoints;
 506	while (*ptr) {
 507		if (debugfs_valid_mountpoint(*ptr) == 0) {
 508			strcpy(hwpoison_debug_fs, *ptr);
 509			return hwpoison_debug_fs;
 510		}
 511		ptr++;
 512	}
 513
 514	/* give up and parse /proc/mounts */
 515	fp = fopen("/proc/mounts", "r");
 516	if (fp == NULL)
 517		perror("Can't open /proc/mounts for read");
 518
 519	while (fscanf(fp, "%*s %"
 520		      STR(MAX_PATH)
 521		      "s %99s %*s %*d %*d\n",
 522		      hwpoison_debug_fs, type) == 2) {
 523		if (strcmp(type, "debugfs") == 0)
 524			break;
 525	}
 526	fclose(fp);
 527
 528	if (strcmp(type, "debugfs") != 0)
 529		return NULL;
 530
 531	return hwpoison_debug_fs;
 532}
 533
 534/* mount the debugfs somewhere if it's not mounted */
 535
 536static void debugfs_mount(void)
 537{
 538	const char **ptr;
 539
 540	/* see if it's already mounted */
 541	if (debugfs_find_mountpoint())
 542		return;
 543
 544	ptr = debugfs_known_mountpoints;
 545	while (*ptr) {
 546		if (mount(NULL, *ptr, "debugfs", 0, NULL) == 0) {
 547			/* save the mountpoint */
 548			strcpy(hwpoison_debug_fs, *ptr);
 549			break;
 550		}
 551		ptr++;
 552	}
 553
 554	if (*ptr == NULL) {
 555		perror("mount debugfs");
 556		exit(EXIT_FAILURE);
 557	}
 558}
 559
 560/*
 561 * page actions
 562 */
 563
 564static void prepare_hwpoison_fd(void)
 565{
 566	char buf[MAX_PATH + 1];
 567
 568	debugfs_mount();
 569
 570	if (opt_hwpoison && !hwpoison_inject_fd) {
 571		snprintf(buf, MAX_PATH, "%s/hwpoison/corrupt-pfn",
 572			hwpoison_debug_fs);
 573		hwpoison_inject_fd = checked_open(buf, O_WRONLY);
 574	}
 575
 576	if (opt_unpoison && !hwpoison_forget_fd) {
 577		snprintf(buf, MAX_PATH, "%s/hwpoison/unpoison-pfn",
 578			hwpoison_debug_fs);
 579		hwpoison_forget_fd = checked_open(buf, O_WRONLY);
 580	}
 581}
 582
 583static int hwpoison_page(unsigned long offset)
 584{
 585	char buf[100];
 586	int len;
 587
 588	len = sprintf(buf, "0x%lx\n", offset);
 589	len = write(hwpoison_inject_fd, buf, len);
 590	if (len < 0) {
 591		perror("hwpoison inject");
 592		return len;
 593	}
 594	return 0;
 595}
 596
 597static int unpoison_page(unsigned long offset)
 598{
 599	char buf[100];
 600	int len;
 601
 602	len = sprintf(buf, "0x%lx\n", offset);
 603	len = write(hwpoison_forget_fd, buf, len);
 604	if (len < 0) {
 605		perror("hwpoison forget");
 606		return len;
 607	}
 608	return 0;
 609}
 610
 611/*
 612 * page frame walker
 613 */
 614
 615static int hash_slot(uint64_t flags)
 616{
 617	int k = HASH_KEY(flags);
 618	int i;
 619
 620	/* Explicitly reserve slot 0 for flags 0: the following logic
 621	 * cannot distinguish an unoccupied slot from slot (flags==0).
 622	 */
 623	if (flags == 0)
 624		return 0;
 625
 626	/* search through the remaining (HASH_SIZE-1) slots */
 627	for (i = 1; i < ARRAY_SIZE(page_flags); i++, k++) {
 628		if (!k || k >= ARRAY_SIZE(page_flags))
 629			k = 1;
 630		if (page_flags[k] == 0) {
 631			page_flags[k] = flags;
 632			return k;
 633		}
 634		if (page_flags[k] == flags)
 635			return k;
 636	}
 637
 638	fatal("hash table full: bump up HASH_SHIFT?\n");
 639	exit(EXIT_FAILURE);
 640}
 641
 642static void add_page(unsigned long voffset,
 643		     unsigned long offset, uint64_t flags)
 644{
 645	flags = kpageflags_flags(flags);
 646
 647	if (!bit_mask_ok(flags))
 648		return;
 649
 650	if (opt_hwpoison)
 651		hwpoison_page(offset);
 652	if (opt_unpoison)
 653		unpoison_page(offset);
 654
 655	if (opt_list == 1)
 656		show_page_range(voffset, offset, flags);
 657	else if (opt_list == 2)
 658		show_page(voffset, offset, flags);
 659
 660	nr_pages[hash_slot(flags)]++;
 661	total_pages++;
 662}
 663
 664#define KPAGEFLAGS_BATCH	(64 << 10)	/* 64k pages */
 665static void walk_pfn(unsigned long voffset,
 666		     unsigned long index,
 667		     unsigned long count)
 668{
 669	uint64_t buf[KPAGEFLAGS_BATCH];
 670	unsigned long batch;
 671	long pages;
 672	unsigned long i;
 673
 674	while (count) {
 675		batch = min_t(unsigned long, count, KPAGEFLAGS_BATCH);
 676		pages = kpageflags_read(buf, index, batch);
 677		if (pages == 0)
 678			break;
 679
 680		for (i = 0; i < pages; i++)
 681			add_page(voffset + i, index + i, buf[i]);
 682
 683		index += pages;
 684		count -= pages;
 685	}
 686}
 687
 688#define PAGEMAP_BATCH	(64 << 10)
 689static void walk_vma(unsigned long index, unsigned long count)
 690{
 691	uint64_t buf[PAGEMAP_BATCH];
 692	unsigned long batch;
 693	unsigned long pages;
 694	unsigned long pfn;
 695	unsigned long i;
 696
 697	while (count) {
 698		batch = min_t(unsigned long, count, PAGEMAP_BATCH);
 699		pages = pagemap_read(buf, index, batch);
 700		if (pages == 0)
 701			break;
 702
 703		for (i = 0; i < pages; i++) {
 704			pfn = pagemap_pfn(buf[i]);
 705			if (pfn)
 706				walk_pfn(index + i, pfn, 1);
 707		}
 708
 709		index += pages;
 710		count -= pages;
 711	}
 712}
 713
 714static void walk_task(unsigned long index, unsigned long count)
 715{
 716	const unsigned long end = index + count;
 717	unsigned long start;
 718	int i = 0;
 719
 720	while (index < end) {
 721
 722		while (pg_end[i] <= index)
 723			if (++i >= nr_vmas)
 724				return;
 725		if (pg_start[i] >= end)
 726			return;
 727
 728		start = max_t(unsigned long, pg_start[i], index);
 729		index = min_t(unsigned long, pg_end[i], end);
 730
 731		assert(start < index);
 732		walk_vma(start, index - start);
 733	}
 734}
 735
 736static void add_addr_range(unsigned long offset, unsigned long size)
 737{
 738	if (nr_addr_ranges >= MAX_ADDR_RANGES)
 739		fatal("too many addr ranges\n");
 740
 741	opt_offset[nr_addr_ranges] = offset;
 742	opt_size[nr_addr_ranges] = min_t(unsigned long, size, ULONG_MAX-offset);
 743	nr_addr_ranges++;
 744}
 745
 746static void walk_addr_ranges(void)
 747{
 748	int i;
 749
 750	kpageflags_fd = checked_open(PROC_KPAGEFLAGS, O_RDONLY);
 751
 752	if (!nr_addr_ranges)
 753		add_addr_range(0, ULONG_MAX);
 754
 755	for (i = 0; i < nr_addr_ranges; i++)
 756		if (!opt_pid)
 757			walk_pfn(0, opt_offset[i], opt_size[i]);
 758		else
 759			walk_task(opt_offset[i], opt_size[i]);
 760
 761	close(kpageflags_fd);
 762}
 763
 764
 765/*
 766 * user interface
 767 */
 768
 769static const char *page_flag_type(uint64_t flag)
 770{
 771	if (flag & KPF_HACKERS_BITS)
 772		return "(r)";
 773	if (flag & KPF_OVERLOADED_BITS)
 774		return "(o)";
 775	return "   ";
 776}
 777
 778static void usage(void)
 779{
 780	int i, j;
 781
 782	printf(
 783"page-types [options]\n"
 784"            -r|--raw                   Raw mode, for kernel developers\n"
 785"            -d|--describe flags        Describe flags\n"
 786"            -a|--addr    addr-spec     Walk a range of pages\n"
 787"            -b|--bits    bits-spec     Walk pages with specified bits\n"
 788"            -p|--pid     pid           Walk process address space\n"
 789#if 0 /* planned features */
 790"            -f|--file    filename      Walk file address space\n"
 791#endif
 792"            -l|--list                  Show page details in ranges\n"
 793"            -L|--list-each             Show page details one by one\n"
 794"            -N|--no-summary            Don't show summary info\n"
 795"            -X|--hwpoison              hwpoison pages\n"
 796"            -x|--unpoison              unpoison pages\n"
 797"            -h|--help                  Show this usage message\n"
 798"flags:\n"
 799"            0x10                       bitfield format, e.g.\n"
 800"            anon                       bit-name, e.g.\n"
 801"            0x10,anon                  comma-separated list, e.g.\n"
 802"addr-spec:\n"
 803"            N                          one page at offset N (unit: pages)\n"
 804"            N+M                        pages range from N to N+M-1\n"
 805"            N,M                        pages range from N to M-1\n"
 806"            N,                         pages range from N to end\n"
 807"            ,M                         pages range from 0 to M-1\n"
 808"bits-spec:\n"
 809"            bit1,bit2                  (flags & (bit1|bit2)) != 0\n"
 810"            bit1,bit2=bit1             (flags & (bit1|bit2)) == bit1\n"
 811"            bit1,~bit2                 (flags & (bit1|bit2)) == bit1\n"
 812"            =bit1,bit2                 flags == (bit1|bit2)\n"
 813"bit-names:\n"
 814	);
 815
 816	for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
 817		if (!page_flag_names[i])
 818			continue;
 819		printf("%16s%s", page_flag_names[i] + 2,
 820				 page_flag_type(1ULL << i));
 821		if (++j > 3) {
 822			j = 0;
 823			putchar('\n');
 824		}
 825	}
 826	printf("\n                                   "
 827		"(r) raw mode bits  (o) overloaded bits\n");
 828}
 829
 830static unsigned long long parse_number(const char *str)
 831{
 832	unsigned long long n;
 833
 834	n = strtoll(str, NULL, 0);
 835
 836	if (n == 0 && str[0] != '0')
 837		fatal("invalid name or number: %s\n", str);
 838
 839	return n;
 840}
 841
 842static void parse_pid(const char *str)
 843{
 844	FILE *file;
 845	char buf[5000];
 846
 847	opt_pid = parse_number(str);
 848
 849	sprintf(buf, "/proc/%d/pagemap", opt_pid);
 850	pagemap_fd = checked_open(buf, O_RDONLY);
 851
 852	sprintf(buf, "/proc/%d/maps", opt_pid);
 853	file = fopen(buf, "r");
 854	if (!file) {
 855		perror(buf);
 856		exit(EXIT_FAILURE);
 857	}
 858
 859	while (fgets(buf, sizeof(buf), file) != NULL) {
 860		unsigned long vm_start;
 861		unsigned long vm_end;
 862		unsigned long long pgoff;
 863		int major, minor;
 864		char r, w, x, s;
 865		unsigned long ino;
 866		int n;
 867
 868		n = sscanf(buf, "%lx-%lx %c%c%c%c %llx %x:%x %lu",
 869			   &vm_start,
 870			   &vm_end,
 871			   &r, &w, &x, &s,
 872			   &pgoff,
 873			   &major, &minor,
 874			   &ino);
 875		if (n < 10) {
 876			fprintf(stderr, "unexpected line: %s\n", buf);
 877			continue;
 878		}
 879		pg_start[nr_vmas] = vm_start / page_size;
 880		pg_end[nr_vmas] = vm_end / page_size;
 881		if (++nr_vmas >= MAX_VMAS) {
 882			fprintf(stderr, "too many VMAs\n");
 883			break;
 884		}
 885	}
 886	fclose(file);
 887}
 888
 889static void parse_file(const char *name)
 890{
 891}
 892
 893static void parse_addr_range(const char *optarg)
 894{
 895	unsigned long offset;
 896	unsigned long size;
 897	char *p;
 898
 899	p = strchr(optarg, ',');
 900	if (!p)
 901		p = strchr(optarg, '+');
 902
 903	if (p == optarg) {
 904		offset = 0;
 905		size   = parse_number(p + 1);
 906	} else if (p) {
 907		offset = parse_number(optarg);
 908		if (p[1] == '\0')
 909			size = ULONG_MAX;
 910		else {
 911			size = parse_number(p + 1);
 912			if (*p == ',') {
 913				if (size < offset)
 914					fatal("invalid range: %lu,%lu\n",
 915							offset, size);
 916				size -= offset;
 917			}
 918		}
 919	} else {
 920		offset = parse_number(optarg);
 921		size   = 1;
 922	}
 923
 924	add_addr_range(offset, size);
 925}
 926
 927static void add_bits_filter(uint64_t mask, uint64_t bits)
 928{
 929	if (nr_bit_filters >= MAX_BIT_FILTERS)
 930		fatal("too much bit filters\n");
 931
 932	opt_mask[nr_bit_filters] = mask;
 933	opt_bits[nr_bit_filters] = bits;
 934	nr_bit_filters++;
 935}
 936
 937static uint64_t parse_flag_name(const char *str, int len)
 938{
 939	int i;
 940
 941	if (!*str || !len)
 942		return 0;
 943
 944	if (len <= 8 && !strncmp(str, "compound", len))
 945		return BITS_COMPOUND;
 946
 947	for (i = 0; i < ARRAY_SIZE(page_flag_names); i++) {
 948		if (!page_flag_names[i])
 949			continue;
 950		if (!strncmp(str, page_flag_names[i] + 2, len))
 951			return 1ULL << i;
 952	}
 953
 954	return parse_number(str);
 955}
 956
 957static uint64_t parse_flag_names(const char *str, int all)
 958{
 959	const char *p    = str;
 960	uint64_t   flags = 0;
 961
 962	while (1) {
 963		if (*p == ',' || *p == '=' || *p == '\0') {
 964			if ((*str != '~') || (*str == '~' && all && *++str))
 965				flags |= parse_flag_name(str, p - str);
 966			if (*p != ',')
 967				break;
 968			str = p + 1;
 969		}
 970		p++;
 971	}
 972
 973	return flags;
 974}
 975
 976static void parse_bits_mask(const char *optarg)
 977{
 978	uint64_t mask;
 979	uint64_t bits;
 980	const char *p;
 981
 982	p = strchr(optarg, '=');
 983	if (p == optarg) {
 984		mask = KPF_ALL_BITS;
 985		bits = parse_flag_names(p + 1, 0);
 986	} else if (p) {
 987		mask = parse_flag_names(optarg, 0);
 988		bits = parse_flag_names(p + 1, 0);
 989	} else if (strchr(optarg, '~')) {
 990		mask = parse_flag_names(optarg, 1);
 991		bits = parse_flag_names(optarg, 0);
 992	} else {
 993		mask = parse_flag_names(optarg, 0);
 994		bits = KPF_ALL_BITS;
 995	}
 996
 997	add_bits_filter(mask, bits);
 998}
 999
1000static void describe_flags(const char *optarg)
1001{
1002	uint64_t flags = parse_flag_names(optarg, 0);
1003
1004	printf("0x%016llx\t%s\t%s\n",
1005		(unsigned long long)flags,
1006		page_flag_name(flags),
1007		page_flag_longname(flags));
1008}
1009
1010static const struct option opts[] = {
1011	{ "raw"       , 0, NULL, 'r' },
1012	{ "pid"       , 1, NULL, 'p' },
1013	{ "file"      , 1, NULL, 'f' },
1014	{ "addr"      , 1, NULL, 'a' },
1015	{ "bits"      , 1, NULL, 'b' },
1016	{ "describe"  , 1, NULL, 'd' },
1017	{ "list"      , 0, NULL, 'l' },
1018	{ "list-each" , 0, NULL, 'L' },
1019	{ "no-summary", 0, NULL, 'N' },
1020	{ "hwpoison"  , 0, NULL, 'X' },
1021	{ "unpoison"  , 0, NULL, 'x' },
1022	{ "help"      , 0, NULL, 'h' },
1023	{ NULL        , 0, NULL, 0 }
1024};
1025
1026int main(int argc, char *argv[])
1027{
1028	int c;
1029
1030	page_size = getpagesize();
1031
1032	while ((c = getopt_long(argc, argv,
1033				"rp:f:a:b:d:lLNXxh", opts, NULL)) != -1) {
1034		switch (c) {
1035		case 'r':
1036			opt_raw = 1;
1037			break;
1038		case 'p':
1039			parse_pid(optarg);
1040			break;
1041		case 'f':
1042			parse_file(optarg);
1043			break;
1044		case 'a':
1045			parse_addr_range(optarg);
1046			break;
1047		case 'b':
1048			parse_bits_mask(optarg);
1049			break;
1050		case 'd':
1051			describe_flags(optarg);
1052			exit(0);
1053		case 'l':
1054			opt_list = 1;
1055			break;
1056		case 'L':
1057			opt_list = 2;
1058			break;
1059		case 'N':
1060			opt_no_summary = 1;
1061			break;
1062		case 'X':
1063			opt_hwpoison = 1;
1064			prepare_hwpoison_fd();
1065			break;
1066		case 'x':
1067			opt_unpoison = 1;
1068			prepare_hwpoison_fd();
1069			break;
1070		case 'h':
1071			usage();
1072			exit(0);
1073		default:
1074			usage();
1075			exit(1);
1076		}
1077	}
1078
1079	if (opt_list && opt_pid)
1080		printf("voffset\t");
1081	if (opt_list == 1)
1082		printf("offset\tlen\tflags\n");
1083	if (opt_list == 2)
1084		printf("offset\tflags\n");
1085
1086	walk_addr_ranges();
1087
1088	if (opt_list == 1)
1089		show_page_range(0, 0, 0);  /* drain the buffer */
1090
1091	if (opt_no_summary)
1092		return 0;
1093
1094	if (opt_list)
1095		printf("\n\n");
1096
1097	show_summary();
1098
1099	return 0;
1100}