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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * page-types: Tool for querying page flags
   4 *
   5 * Copyright (C) 2009 Intel corporation
   6 *
   7 * Authors: Wu Fengguang <fengguang.wu@intel.com>
   8 */
   9
  10#define _FILE_OFFSET_BITS 64
  11#define _GNU_SOURCE
  12#include <stdio.h>
  13#include <stdlib.h>
  14#include <unistd.h>
  15#include <stdint.h>
  16#include <stdarg.h>
  17#include <string.h>
  18#include <getopt.h>
  19#include <limits.h>
  20#include <assert.h>
  21#include <ftw.h>
  22#include <time.h>
  23#include <setjmp.h>
  24#include <signal.h>
  25#include <sys/types.h>
  26#include <sys/errno.h>
  27#include <sys/fcntl.h>
  28#include <sys/mount.h>
  29#include <sys/statfs.h>
  30#include <sys/mman.h>
  31#include "../../include/uapi/linux/magic.h"
  32#include "../../include/uapi/linux/kernel-page-flags.h"
  33#include <api/fs/fs.h>
  34
  35#ifndef MAX_PATH
  36# define MAX_PATH 256
  37#endif
  38
  39#ifndef STR
  40# define _STR(x) #x
  41# define STR(x) _STR(x)
  42#endif
  43
  44/*
  45 * pagemap kernel ABI bits
  46 */
  47
  48#define PM_ENTRY_BYTES		8
  49#define PM_PFRAME_BITS		55
  50#define PM_PFRAME_MASK		((1LL << PM_PFRAME_BITS) - 1)
  51#define PM_PFRAME(x)		((x) & PM_PFRAME_MASK)
  52#define MAX_SWAPFILES_SHIFT	5
  53#define PM_SWAP_OFFSET(x)	(((x) & PM_PFRAME_MASK) >> MAX_SWAPFILES_SHIFT)
  54#define PM_SOFT_DIRTY		(1ULL << 55)
  55#define PM_MMAP_EXCLUSIVE	(1ULL << 56)
  56#define PM_FILE			(1ULL << 61)
  57#define PM_SWAP			(1ULL << 62)
  58#define PM_PRESENT		(1ULL << 63)
  59
  60/*
  61 * kernel page flags
  62 */
  63
  64#define KPF_BYTES		8
  65#define PROC_KPAGEFLAGS		"/proc/kpageflags"
  66#define PROC_KPAGECOUNT		"/proc/kpagecount"
  67#define PROC_KPAGECGROUP	"/proc/kpagecgroup"
  68
  69#define SYS_KERNEL_MM_PAGE_IDLE "/sys/kernel/mm/page_idle/bitmap"
  70
  71/* [32-] kernel hacking assistances */
  72#define KPF_RESERVED		32
  73#define KPF_MLOCKED		33
  74#define KPF_MAPPEDTODISK	34
  75#define KPF_PRIVATE		35
  76#define KPF_PRIVATE_2		36
  77#define KPF_OWNER_PRIVATE	37
  78#define KPF_ARCH		38
  79#define KPF_UNCACHED		39
  80#define KPF_SOFTDIRTY		40
  81#define KPF_ARCH_2		41
  82
  83/* [47-] take some arbitrary free slots for expanding overloaded flags
  84 * not part of kernel API
  85 */
  86#define KPF_ANON_EXCLUSIVE	47
  87#define KPF_READAHEAD		48
  88#define KPF_SLUB_FROZEN		50
  89#define KPF_SLUB_DEBUG		51
  90#define KPF_FILE		61
  91#define KPF_SWAP		62
  92#define KPF_MMAP_EXCLUSIVE	63
  93
  94#define KPF_ALL_BITS		((uint64_t)~0ULL)
  95#define KPF_HACKERS_BITS	(0xffffULL << 32)
  96#define KPF_OVERLOADED_BITS	(0xffffULL << 48)
  97#define BIT(name)		(1ULL << KPF_##name)
  98#define BITS_COMPOUND		(BIT(COMPOUND_HEAD) | BIT(COMPOUND_TAIL))
  99
 100static const char * const page_flag_names[] = {
 101	[KPF_LOCKED]		= "L:locked",
 102	[KPF_ERROR]		= "E:error",
 103	[KPF_REFERENCED]	= "R:referenced",
 104	[KPF_UPTODATE]		= "U:uptodate",
 105	[KPF_DIRTY]		= "D:dirty",
 106	[KPF_LRU]		= "l:lru",
 107	[KPF_ACTIVE]		= "A:active",
 108	[KPF_SLAB]		= "S:slab",
 109	[KPF_WRITEBACK]		= "W:writeback",
 110	[KPF_RECLAIM]		= "I:reclaim",
 111	[KPF_BUDDY]		= "B:buddy",
 112
 113	[KPF_MMAP]		= "M:mmap",
 114	[KPF_ANON]		= "a:anonymous",
 115	[KPF_SWAPCACHE]		= "s:swapcache",
 116	[KPF_SWAPBACKED]	= "b:swapbacked",
 117	[KPF_COMPOUND_HEAD]	= "H:compound_head",
 118	[KPF_COMPOUND_TAIL]	= "T:compound_tail",
 119	[KPF_HUGE]		= "G:huge",
 120	[KPF_UNEVICTABLE]	= "u:unevictable",
 121	[KPF_HWPOISON]		= "X:hwpoison",
 122	[KPF_NOPAGE]		= "n:nopage",
 123	[KPF_KSM]		= "x:ksm",
 124	[KPF_THP]		= "t:thp",
 125	[KPF_OFFLINE]		= "o:offline",
 126	[KPF_PGTABLE]		= "g:pgtable",
 127	[KPF_ZERO_PAGE]		= "z:zero_page",
 128	[KPF_IDLE]              = "i:idle_page",
 129
 130	[KPF_RESERVED]		= "r:reserved",
 131	[KPF_MLOCKED]		= "m:mlocked",
 132	[KPF_MAPPEDTODISK]	= "d:mappedtodisk",
 133	[KPF_PRIVATE]		= "P:private",
 134	[KPF_PRIVATE_2]		= "p:private_2",
 135	[KPF_OWNER_PRIVATE]	= "O:owner_private",
 136	[KPF_ARCH]		= "h:arch",
 137	[KPF_UNCACHED]		= "c:uncached",
 138	[KPF_SOFTDIRTY]		= "f:softdirty",
 139	[KPF_ARCH_2]		= "H:arch_2",
 140
 141	[KPF_ANON_EXCLUSIVE]	= "d:anon_exclusive",
 142	[KPF_READAHEAD]		= "I:readahead",
 143	[KPF_SLUB_FROZEN]	= "A:slub_frozen",
 144	[KPF_SLUB_DEBUG]	= "E:slub_debug",
 145
 146	[KPF_FILE]		= "F:file",
 147	[KPF_SWAP]		= "w:swap",
 148	[KPF_MMAP_EXCLUSIVE]	= "1:mmap_exclusive",
 149};
 150
 151
 152/*
 153 * data structures
 154 */
 155
 156static int		opt_raw;	/* for kernel developers */
 157static int		opt_list;	/* list pages (in ranges) */
 158static int		opt_mark_idle;	/* set accessed bit */
 159static int		opt_no_summary;	/* don't show summary */
 160static pid_t		opt_pid;	/* process to walk */
 161const char		*opt_file;	/* file or directory path */
 162static uint64_t		opt_cgroup;	/* cgroup inode */
 163static int		opt_list_cgroup;/* list page cgroup */
 164static int		opt_list_mapcnt;/* list page map count */
 165static const char	*opt_kpageflags;/* kpageflags file to parse */
 166
 167#define MAX_ADDR_RANGES	1024
 168static int		nr_addr_ranges;
 169static unsigned long	opt_offset[MAX_ADDR_RANGES];
 170static unsigned long	opt_size[MAX_ADDR_RANGES];
 171
 172#define MAX_VMAS	10240
 173static int		nr_vmas;
 174static unsigned long	pg_start[MAX_VMAS];
 175static unsigned long	pg_end[MAX_VMAS];
 176
 177#define MAX_BIT_FILTERS	64
 178static int		nr_bit_filters;
 179static uint64_t		opt_mask[MAX_BIT_FILTERS];
 180static uint64_t		opt_bits[MAX_BIT_FILTERS];
 181
 182static int		page_size;
 183
 184static int		pagemap_fd;
 185static int		kpageflags_fd;
 186static int		kpagecount_fd = -1;
 187static int		kpagecgroup_fd = -1;
 188static int		page_idle_fd = -1;
 189
 190static int		opt_hwpoison;
 191static int		opt_unpoison;
 192
 193static const char	*hwpoison_debug_fs;
 194static int		hwpoison_inject_fd;
 195static int		hwpoison_forget_fd;
 196
 197#define HASH_SHIFT	13
 198#define HASH_SIZE	(1 << HASH_SHIFT)
 199#define HASH_MASK	(HASH_SIZE - 1)
 200#define HASH_KEY(flags)	(flags & HASH_MASK)
 201
 202static unsigned long	total_pages;
 203static unsigned long	nr_pages[HASH_SIZE];
 204static uint64_t		page_flags[HASH_SIZE];
 205
 206
 207/*
 208 * helper functions
 209 */
 210
 211#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
 212
 213#define min_t(type, x, y) ({			\
 214	type __min1 = (x);			\
 215	type __min2 = (y);			\
 216	__min1 < __min2 ? __min1 : __min2; })
 217
 218#define max_t(type, x, y) ({			\
 219	type __max1 = (x);			\
 220	type __max2 = (y);			\
 221	__max1 > __max2 ? __max1 : __max2; })
 222
 223static unsigned long pages2mb(unsigned long pages)
 224{
 225	return (pages * page_size) >> 20;
 226}
 227
 228static void fatal(const char *x, ...)
 229{
 230	va_list ap;
 231
 232	va_start(ap, x);
 233	vfprintf(stderr, x, ap);
 234	va_end(ap);
 235	exit(EXIT_FAILURE);
 236}
 237
 238static int checked_open(const char *pathname, int flags)
 239{
 240	int fd = open(pathname, flags);
 241
 242	if (fd < 0) {
 243		perror(pathname);
 244		exit(EXIT_FAILURE);
 245	}
 246
 247	return fd;
 248}
 249
 250/*
 251 * pagemap/kpageflags routines
 252 */
 253
 254static unsigned long do_u64_read(int fd, const char *name,
 255				 uint64_t *buf,
 256				 unsigned long index,
 257				 unsigned long count)
 258{
 259	long bytes;
 260
 261	if (index > ULONG_MAX / 8)
 262		fatal("index overflow: %lu\n", index);
 263
 264	bytes = pread(fd, buf, count * 8, (off_t)index * 8);
 265	if (bytes < 0) {
 266		perror(name);
 267		exit(EXIT_FAILURE);
 268	}
 269	if (bytes % 8)
 270		fatal("partial read: %lu bytes\n", bytes);
 271
 272	return bytes / 8;
 273}
 274
 275static unsigned long kpageflags_read(uint64_t *buf,
 276				     unsigned long index,
 277				     unsigned long pages)
 278{
 279	return do_u64_read(kpageflags_fd, opt_kpageflags, buf, index, pages);
 280}
 281
 282static unsigned long kpagecgroup_read(uint64_t *buf,
 283				      unsigned long index,
 284				      unsigned long pages)
 285{
 286	if (kpagecgroup_fd < 0)
 287		return pages;
 288
 289	return do_u64_read(kpagecgroup_fd, opt_kpageflags, buf, index, pages);
 290}
 291
 292static unsigned long kpagecount_read(uint64_t *buf,
 293				     unsigned long index,
 294				     unsigned long pages)
 295{
 296	return kpagecount_fd < 0 ? pages :
 297		do_u64_read(kpagecount_fd, PROC_KPAGECOUNT,
 298			    buf, index, pages);
 299}
 300
 301static unsigned long pagemap_read(uint64_t *buf,
 302				  unsigned long index,
 303				  unsigned long pages)
 304{
 305	return do_u64_read(pagemap_fd, "/proc/pid/pagemap", buf, index, pages);
 306}
 307
 308static unsigned long pagemap_pfn(uint64_t val)
 309{
 310	unsigned long pfn;
 311
 312	if (val & PM_PRESENT)
 313		pfn = PM_PFRAME(val);
 314	else
 315		pfn = 0;
 316
 317	return pfn;
 318}
 319
 320static unsigned long pagemap_swap_offset(uint64_t val)
 321{
 322	return val & PM_SWAP ? PM_SWAP_OFFSET(val) : 0;
 323}
 324
 325/*
 326 * page flag names
 327 */
 328
 329static char *page_flag_name(uint64_t flags)
 330{
 331	static char buf[65];
 332	int present;
 333	size_t i, j;
 334
 335	for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
 336		present = (flags >> i) & 1;
 337		if (!page_flag_names[i]) {
 338			if (present)
 339				fatal("unknown flag bit %d\n", i);
 340			continue;
 341		}
 342		buf[j++] = present ? page_flag_names[i][0] : '_';
 343	}
 344
 345	return buf;
 346}
 347
 348static char *page_flag_longname(uint64_t flags)
 349{
 350	static char buf[1024];
 351	size_t i, n;
 352
 353	for (i = 0, n = 0; i < ARRAY_SIZE(page_flag_names); i++) {
 354		if (!page_flag_names[i])
 355			continue;
 356		if ((flags >> i) & 1)
 357			n += snprintf(buf + n, sizeof(buf) - n, "%s,",
 358					page_flag_names[i] + 2);
 359	}
 360	if (n)
 361		n--;
 362	buf[n] = '\0';
 363
 364	return buf;
 365}
 366
 367
 368/*
 369 * page list and summary
 370 */
 371
 372static void show_page_range(unsigned long voffset, unsigned long offset,
 373			    unsigned long size, uint64_t flags,
 374			    uint64_t cgroup, uint64_t mapcnt)
 375{
 376	static uint64_t      flags0;
 377	static uint64_t	     cgroup0;
 378	static uint64_t      mapcnt0;
 379	static unsigned long voff;
 380	static unsigned long index;
 381	static unsigned long count;
 382
 383	if (flags == flags0 && cgroup == cgroup0 && mapcnt == mapcnt0 &&
 384	    offset == index + count && size && voffset == voff + count) {
 385		count += size;
 386		return;
 387	}
 388
 389	if (count) {
 390		if (opt_pid)
 391			printf("%lx\t", voff);
 392		if (opt_file)
 393			printf("%lx\t", voff);
 394		if (opt_list_cgroup)
 395			printf("@%llu\t", (unsigned long long)cgroup0);
 396		if (opt_list_mapcnt)
 397			printf("%lu\t", mapcnt0);
 398		printf("%lx\t%lx\t%s\n",
 399				index, count, page_flag_name(flags0));
 400	}
 401
 402	flags0 = flags;
 403	cgroup0 = cgroup;
 404	mapcnt0 = mapcnt;
 405	index  = offset;
 406	voff   = voffset;
 407	count  = size;
 408}
 409
 410static void flush_page_range(void)
 411{
 412	show_page_range(0, 0, 0, 0, 0, 0);
 413}
 414
 415static void show_page(unsigned long voffset, unsigned long offset,
 416		      uint64_t flags, uint64_t cgroup, uint64_t mapcnt)
 417{
 418	if (opt_pid)
 419		printf("%lx\t", voffset);
 420	if (opt_file)
 421		printf("%lx\t", voffset);
 422	if (opt_list_cgroup)
 423		printf("@%llu\t", (unsigned long long)cgroup);
 424	if (opt_list_mapcnt)
 425		printf("%lu\t", mapcnt);
 426
 427	printf("%lx\t%s\n", offset, page_flag_name(flags));
 428}
 429
 430static void show_summary(void)
 431{
 432	size_t i;
 433
 434	printf("             flags\tpage-count       MB"
 435		"  symbolic-flags\t\t\tlong-symbolic-flags\n");
 436
 437	for (i = 0; i < ARRAY_SIZE(nr_pages); i++) {
 438		if (nr_pages[i])
 439			printf("0x%016llx\t%10lu %8lu  %s\t%s\n",
 440				(unsigned long long)page_flags[i],
 441				nr_pages[i],
 442				pages2mb(nr_pages[i]),
 443				page_flag_name(page_flags[i]),
 444				page_flag_longname(page_flags[i]));
 445	}
 446
 447	printf("             total\t%10lu %8lu\n",
 448			total_pages, pages2mb(total_pages));
 449}
 450
 451
 452/*
 453 * page flag filters
 454 */
 455
 456static int bit_mask_ok(uint64_t flags)
 457{
 458	int i;
 459
 460	for (i = 0; i < nr_bit_filters; i++) {
 461		if (opt_bits[i] == KPF_ALL_BITS) {
 462			if ((flags & opt_mask[i]) == 0)
 463				return 0;
 464		} else {
 465			if ((flags & opt_mask[i]) != opt_bits[i])
 466				return 0;
 467		}
 468	}
 469
 470	return 1;
 471}
 472
 473static uint64_t expand_overloaded_flags(uint64_t flags, uint64_t pme)
 474{
 475	/* Anonymous pages overload PG_mappedtodisk */
 476	if ((flags & BIT(ANON)) && (flags & BIT(MAPPEDTODISK)))
 477		flags ^= BIT(MAPPEDTODISK) | BIT(ANON_EXCLUSIVE);
 478
 479	/* SLUB overloads several page flags */
 480	if (flags & BIT(SLAB)) {
 481		if (flags & BIT(ACTIVE))
 482			flags ^= BIT(ACTIVE) | BIT(SLUB_FROZEN);
 483		if (flags & BIT(ERROR))
 484			flags ^= BIT(ERROR) | BIT(SLUB_DEBUG);
 485	}
 486
 487	/* PG_reclaim is overloaded as PG_readahead in the read path */
 488	if ((flags & (BIT(RECLAIM) | BIT(WRITEBACK))) == BIT(RECLAIM))
 489		flags ^= BIT(RECLAIM) | BIT(READAHEAD);
 490
 491	if (pme & PM_SOFT_DIRTY)
 492		flags |= BIT(SOFTDIRTY);
 493	if (pme & PM_FILE)
 494		flags |= BIT(FILE);
 495	if (pme & PM_SWAP)
 496		flags |= BIT(SWAP);
 497	if (pme & PM_MMAP_EXCLUSIVE)
 498		flags |= BIT(MMAP_EXCLUSIVE);
 499
 500	return flags;
 501}
 502
 503static uint64_t well_known_flags(uint64_t flags)
 504{
 505	/* hide flags intended only for kernel hacker */
 506	flags &= ~KPF_HACKERS_BITS;
 507
 508	/* hide non-hugeTLB compound pages */
 509	if ((flags & BITS_COMPOUND) && !(flags & BIT(HUGE)))
 510		flags &= ~BITS_COMPOUND;
 511
 512	return flags;
 513}
 514
 515static uint64_t kpageflags_flags(uint64_t flags, uint64_t pme)
 516{
 517	if (opt_raw)
 518		flags = expand_overloaded_flags(flags, pme);
 519	else
 520		flags = well_known_flags(flags);
 521
 522	return flags;
 523}
 524
 525/*
 526 * page actions
 527 */
 528
 529static void prepare_hwpoison_fd(void)
 530{
 531	char buf[MAX_PATH + 1];
 532
 533	hwpoison_debug_fs = debugfs__mount();
 534	if (!hwpoison_debug_fs) {
 535		perror("mount debugfs");
 536		exit(EXIT_FAILURE);
 537	}
 538
 539	if (opt_hwpoison && !hwpoison_inject_fd) {
 540		snprintf(buf, MAX_PATH, "%s/hwpoison/corrupt-pfn",
 541			hwpoison_debug_fs);
 542		hwpoison_inject_fd = checked_open(buf, O_WRONLY);
 543	}
 544
 545	if (opt_unpoison && !hwpoison_forget_fd) {
 546		snprintf(buf, MAX_PATH, "%s/hwpoison/unpoison-pfn",
 547			hwpoison_debug_fs);
 548		hwpoison_forget_fd = checked_open(buf, O_WRONLY);
 549	}
 550}
 551
 552static int hwpoison_page(unsigned long offset)
 553{
 554	char buf[100];
 555	int len;
 556
 557	len = sprintf(buf, "0x%lx\n", offset);
 558	len = write(hwpoison_inject_fd, buf, len);
 559	if (len < 0) {
 560		perror("hwpoison inject");
 561		return len;
 562	}
 563	return 0;
 564}
 565
 566static int unpoison_page(unsigned long offset)
 567{
 568	char buf[100];
 569	int len;
 570
 571	len = sprintf(buf, "0x%lx\n", offset);
 572	len = write(hwpoison_forget_fd, buf, len);
 573	if (len < 0) {
 574		perror("hwpoison forget");
 575		return len;
 576	}
 577	return 0;
 578}
 579
 580static int mark_page_idle(unsigned long offset)
 581{
 582	static unsigned long off;
 583	static uint64_t buf;
 584	int len;
 585
 586	if ((offset / 64 == off / 64) || buf == 0) {
 587		buf |= 1UL << (offset % 64);
 588		off = offset;
 589		return 0;
 590	}
 591
 592	len = pwrite(page_idle_fd, &buf, 8, 8 * (off / 64));
 593	if (len < 0) {
 594		perror("mark page idle");
 595		return len;
 596	}
 597
 598	buf = 1UL << (offset % 64);
 599	off = offset;
 600
 601	return 0;
 602}
 603
 604/*
 605 * page frame walker
 606 */
 607
 608static size_t hash_slot(uint64_t flags)
 609{
 610	size_t k = HASH_KEY(flags);
 611	size_t i;
 612
 613	/* Explicitly reserve slot 0 for flags 0: the following logic
 614	 * cannot distinguish an unoccupied slot from slot (flags==0).
 615	 */
 616	if (flags == 0)
 617		return 0;
 618
 619	/* search through the remaining (HASH_SIZE-1) slots */
 620	for (i = 1; i < ARRAY_SIZE(page_flags); i++, k++) {
 621		if (!k || k >= ARRAY_SIZE(page_flags))
 622			k = 1;
 623		if (page_flags[k] == 0) {
 624			page_flags[k] = flags;
 625			return k;
 626		}
 627		if (page_flags[k] == flags)
 628			return k;
 629	}
 630
 631	fatal("hash table full: bump up HASH_SHIFT?\n");
 632	exit(EXIT_FAILURE);
 633}
 634
 635static void add_page(unsigned long voffset, unsigned long offset,
 636		     uint64_t flags, uint64_t cgroup, uint64_t mapcnt,
 637		     uint64_t pme)
 638{
 639	flags = kpageflags_flags(flags, pme);
 640
 641	if (!bit_mask_ok(flags))
 642		return;
 643
 644	if (opt_cgroup && cgroup != (uint64_t)opt_cgroup)
 645		return;
 646
 647	if (opt_hwpoison)
 648		hwpoison_page(offset);
 649	if (opt_unpoison)
 650		unpoison_page(offset);
 651
 652	if (opt_mark_idle)
 653		mark_page_idle(offset);
 654
 655	if (opt_list == 1)
 656		show_page_range(voffset, offset, 1, flags, cgroup, mapcnt);
 657	else if (opt_list == 2)
 658		show_page(voffset, offset, flags, cgroup, mapcnt);
 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		     uint64_t pme)
 669{
 670	uint64_t buf[KPAGEFLAGS_BATCH];
 671	uint64_t cgi[KPAGEFLAGS_BATCH];
 672	uint64_t cnt[KPAGEFLAGS_BATCH];
 673	unsigned long batch;
 674	unsigned long pages;
 675	unsigned long i;
 676
 677	/*
 678	 * kpagecgroup_read() reads only if kpagecgroup were opened, but
 679	 * /proc/kpagecgroup might even not exist, so it's better to fill
 680	 * them with zeros here.
 681	 */
 682	if (count == 1)
 683		cgi[0] = 0;
 684	else
 685		memset(cgi, 0, sizeof cgi);
 686
 687	while (count) {
 688		batch = min_t(unsigned long, count, KPAGEFLAGS_BATCH);
 689		pages = kpageflags_read(buf, index, batch);
 690		if (pages == 0)
 691			break;
 692
 693		if (kpagecgroup_read(cgi, index, pages) != pages)
 694			fatal("kpagecgroup returned fewer pages than expected");
 695
 696		if (kpagecount_read(cnt, index, pages) != pages)
 697			fatal("kpagecount returned fewer pages than expected");
 698
 699		for (i = 0; i < pages; i++)
 700			add_page(voffset + i, index + i,
 701				 buf[i], cgi[i], cnt[i], pme);
 702
 703		index += pages;
 704		count -= pages;
 705	}
 706}
 707
 708static void walk_swap(unsigned long voffset, uint64_t pme)
 709{
 710	uint64_t flags = kpageflags_flags(0, pme);
 711
 712	if (!bit_mask_ok(flags))
 713		return;
 714
 715	if (opt_cgroup)
 716		return;
 717
 718	if (opt_list == 1)
 719		show_page_range(voffset, pagemap_swap_offset(pme),
 720				1, flags, 0, 0);
 721	else if (opt_list == 2)
 722		show_page(voffset, pagemap_swap_offset(pme), flags, 0, 0);
 723
 724	nr_pages[hash_slot(flags)]++;
 725	total_pages++;
 726}
 727
 728#define PAGEMAP_BATCH	(64 << 10)
 729static void walk_vma(unsigned long index, unsigned long count)
 730{
 731	uint64_t buf[PAGEMAP_BATCH];
 732	unsigned long batch;
 733	unsigned long pages;
 734	unsigned long pfn;
 735	unsigned long i;
 736
 737	while (count) {
 738		batch = min_t(unsigned long, count, PAGEMAP_BATCH);
 739		pages = pagemap_read(buf, index, batch);
 740		if (pages == 0)
 741			break;
 742
 743		for (i = 0; i < pages; i++) {
 744			pfn = pagemap_pfn(buf[i]);
 745			if (pfn)
 746				walk_pfn(index + i, pfn, 1, buf[i]);
 747			if (buf[i] & PM_SWAP)
 748				walk_swap(index + i, buf[i]);
 749		}
 750
 751		index += pages;
 752		count -= pages;
 753	}
 754}
 755
 756static void walk_task(unsigned long index, unsigned long count)
 757{
 758	const unsigned long end = index + count;
 759	unsigned long start;
 760	int i = 0;
 761
 762	while (index < end) {
 763
 764		while (pg_end[i] <= index)
 765			if (++i >= nr_vmas)
 766				return;
 767		if (pg_start[i] >= end)
 768			return;
 769
 770		start = max_t(unsigned long, pg_start[i], index);
 771		index = min_t(unsigned long, pg_end[i], end);
 772
 773		assert(start < index);
 774		walk_vma(start, index - start);
 775	}
 776}
 777
 778static void add_addr_range(unsigned long offset, unsigned long size)
 779{
 780	if (nr_addr_ranges >= MAX_ADDR_RANGES)
 781		fatal("too many addr ranges\n");
 782
 783	opt_offset[nr_addr_ranges] = offset;
 784	opt_size[nr_addr_ranges] = min_t(unsigned long, size, ULONG_MAX-offset);
 785	nr_addr_ranges++;
 786}
 787
 788static void walk_addr_ranges(void)
 789{
 790	int i;
 791
 792	kpageflags_fd = checked_open(opt_kpageflags, O_RDONLY);
 793
 794	if (!nr_addr_ranges)
 795		add_addr_range(0, ULONG_MAX);
 796
 797	for (i = 0; i < nr_addr_ranges; i++)
 798		if (!opt_pid)
 799			walk_pfn(opt_offset[i], opt_offset[i], opt_size[i], 0);
 800		else
 801			walk_task(opt_offset[i], opt_size[i]);
 802
 803	if (opt_mark_idle)
 804		mark_page_idle(0);
 805
 806	close(kpageflags_fd);
 807}
 808
 809
 810/*
 811 * user interface
 812 */
 813
 814static const char *page_flag_type(uint64_t flag)
 815{
 816	if (flag & KPF_HACKERS_BITS)
 817		return "(r)";
 818	if (flag & KPF_OVERLOADED_BITS)
 819		return "(o)";
 820	return "   ";
 821}
 822
 823static void usage(void)
 824{
 825	size_t i, j;
 826
 827	printf(
 828"page-types [options]\n"
 829"            -r|--raw                   Raw mode, for kernel developers\n"
 830"            -d|--describe flags        Describe flags\n"
 831"            -a|--addr    addr-spec     Walk a range of pages\n"
 832"            -b|--bits    bits-spec     Walk pages with specified bits\n"
 833"            -c|--cgroup  path|@inode   Walk pages within memory cgroup\n"
 834"            -p|--pid     pid           Walk process address space\n"
 835"            -f|--file    filename      Walk file address space\n"
 836"            -i|--mark-idle             Mark pages idle\n"
 837"            -l|--list                  Show page details in ranges\n"
 838"            -L|--list-each             Show page details one by one\n"
 839"            -C|--list-cgroup           Show cgroup inode for pages\n"
 840"            -M|--list-mapcnt           Show page map count\n"
 841"            -N|--no-summary            Don't show summary info\n"
 842"            -X|--hwpoison              hwpoison pages\n"
 843"            -x|--unpoison              unpoison pages\n"
 844"            -F|--kpageflags filename   kpageflags file to parse\n"
 845"            -h|--help                  Show this usage message\n"
 846"flags:\n"
 847"            0x10                       bitfield format, e.g.\n"
 848"            anon                       bit-name, e.g.\n"
 849"            0x10,anon                  comma-separated list, e.g.\n"
 850"addr-spec:\n"
 851"            N                          one page at offset N (unit: pages)\n"
 852"            N+M                        pages range from N to N+M-1\n"
 853"            N,M                        pages range from N to M-1\n"
 854"            N,                         pages range from N to end\n"
 855"            ,M                         pages range from 0 to M-1\n"
 856"bits-spec:\n"
 857"            bit1,bit2                  (flags & (bit1|bit2)) != 0\n"
 858"            bit1,bit2=bit1             (flags & (bit1|bit2)) == bit1\n"
 859"            bit1,~bit2                 (flags & (bit1|bit2)) == bit1\n"
 860"            =bit1,bit2                 flags == (bit1|bit2)\n"
 861"bit-names:\n"
 862	);
 863
 864	for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
 865		if (!page_flag_names[i])
 866			continue;
 867		printf("%16s%s", page_flag_names[i] + 2,
 868				 page_flag_type(1ULL << i));
 869		if (++j > 3) {
 870			j = 0;
 871			putchar('\n');
 872		}
 873	}
 874	printf("\n                                   "
 875		"(r) raw mode bits  (o) overloaded bits\n");
 876}
 877
 878static unsigned long long parse_number(const char *str)
 879{
 880	unsigned long long n;
 881
 882	n = strtoll(str, NULL, 0);
 883
 884	if (n == 0 && str[0] != '0')
 885		fatal("invalid name or number: %s\n", str);
 886
 887	return n;
 888}
 889
 890static void parse_pid(const char *str)
 891{
 892	FILE *file;
 893	char buf[5000];
 894
 895	opt_pid = parse_number(str);
 896
 897	sprintf(buf, "/proc/%d/pagemap", opt_pid);
 898	pagemap_fd = checked_open(buf, O_RDONLY);
 899
 900	sprintf(buf, "/proc/%d/maps", opt_pid);
 901	file = fopen(buf, "r");
 902	if (!file) {
 903		perror(buf);
 904		exit(EXIT_FAILURE);
 905	}
 906
 907	while (fgets(buf, sizeof(buf), file) != NULL) {
 908		unsigned long vm_start;
 909		unsigned long vm_end;
 910		unsigned long long pgoff;
 911		int major, minor;
 912		char r, w, x, s;
 913		unsigned long ino;
 914		int n;
 915
 916		n = sscanf(buf, "%lx-%lx %c%c%c%c %llx %x:%x %lu",
 917			   &vm_start,
 918			   &vm_end,
 919			   &r, &w, &x, &s,
 920			   &pgoff,
 921			   &major, &minor,
 922			   &ino);
 923		if (n < 10) {
 924			fprintf(stderr, "unexpected line: %s\n", buf);
 925			continue;
 926		}
 927		pg_start[nr_vmas] = vm_start / page_size;
 928		pg_end[nr_vmas] = vm_end / page_size;
 929		if (++nr_vmas >= MAX_VMAS) {
 930			fprintf(stderr, "too many VMAs\n");
 931			break;
 932		}
 933	}
 934	fclose(file);
 935}
 936
 937static void show_file(const char *name, const struct stat *st)
 938{
 939	unsigned long long size = st->st_size;
 940	char atime[64], mtime[64];
 941	long now = time(NULL);
 942
 943	printf("%s\tInode: %u\tSize: %llu (%llu pages)\n",
 944			name, (unsigned)st->st_ino,
 945			size, (size + page_size - 1) / page_size);
 946
 947	strftime(atime, sizeof(atime), "%c", localtime(&st->st_atime));
 948	strftime(mtime, sizeof(mtime), "%c", localtime(&st->st_mtime));
 949
 950	printf("Modify: %s (%ld seconds ago)\nAccess: %s (%ld seconds ago)\n",
 951			mtime, now - st->st_mtime,
 952			atime, now - st->st_atime);
 953}
 954
 955static sigjmp_buf sigbus_jmp;
 956
 957static void * volatile sigbus_addr;
 958
 959static void sigbus_handler(int sig, siginfo_t *info, void *ucontex)
 960{
 961	(void)sig;
 962	(void)ucontex;
 963	sigbus_addr = info ? info->si_addr : NULL;
 964	siglongjmp(sigbus_jmp, 1);
 965}
 966
 967static struct sigaction sigbus_action = {
 968	.sa_sigaction = sigbus_handler,
 969	.sa_flags = SA_SIGINFO,
 970};
 971
 972static void walk_file_range(const char *name, int fd,
 973			    unsigned long off, unsigned long end)
 974{
 975	uint8_t vec[PAGEMAP_BATCH];
 976	uint64_t buf[PAGEMAP_BATCH], flags;
 977	uint64_t cgroup = 0;
 978	uint64_t mapcnt = 0;
 979	unsigned long nr_pages, pfn, i;
 980	ssize_t len;
 981	void *ptr;
 982	int first = 1;
 983
 984	for (; off < end; off += len) {
 985		nr_pages = (end - off + page_size - 1) / page_size;
 986		if (nr_pages > PAGEMAP_BATCH)
 987			nr_pages = PAGEMAP_BATCH;
 988		len = nr_pages * page_size;
 989
 990		ptr = mmap(NULL, len, PROT_READ, MAP_SHARED, fd, off);
 991		if (ptr == MAP_FAILED)
 992			fatal("mmap failed: %s", name);
 993
 994		/* determine cached pages */
 995		if (mincore(ptr, len, vec))
 996			fatal("mincore failed: %s", name);
 997
 998		/* turn off readahead */
 999		if (madvise(ptr, len, MADV_RANDOM))
1000			fatal("madvice failed: %s", name);
1001
1002		if (sigsetjmp(sigbus_jmp, 1)) {
1003			end = off + sigbus_addr ? sigbus_addr - ptr : 0;
1004			fprintf(stderr, "got sigbus at offset %lld: %s\n",
1005					(long long)end, name);
1006			goto got_sigbus;
1007		}
1008
1009		/* populate ptes */
1010		for (i = 0; i < nr_pages ; i++) {
1011			if (vec[i] & 1)
1012				(void)*(volatile int *)(ptr + i * page_size);
1013		}
1014got_sigbus:
1015
1016		/* turn off harvesting reference bits */
1017		if (madvise(ptr, len, MADV_SEQUENTIAL))
1018			fatal("madvice failed: %s", name);
1019
1020		if (pagemap_read(buf, (unsigned long)ptr / page_size,
1021					nr_pages) != nr_pages)
1022			fatal("cannot read pagemap");
1023
1024		munmap(ptr, len);
1025
1026		for (i = 0; i < nr_pages; i++) {
1027			pfn = pagemap_pfn(buf[i]);
1028			if (!pfn)
1029				continue;
1030			if (!kpageflags_read(&flags, pfn, 1))
1031				continue;
1032			if (!kpagecgroup_read(&cgroup, pfn, 1))
1033				fatal("kpagecgroup_read failed");
1034			if (!kpagecount_read(&mapcnt, pfn, 1))
1035				fatal("kpagecount_read failed");
1036			if (first && opt_list) {
1037				first = 0;
1038				flush_page_range();
1039			}
1040			add_page(off / page_size + i, pfn,
1041				 flags, cgroup, mapcnt, buf[i]);
1042		}
1043	}
1044}
1045
1046static void walk_file(const char *name, const struct stat *st)
1047{
1048	int i;
1049	int fd;
1050
1051	fd = checked_open(name, O_RDONLY|O_NOATIME|O_NOFOLLOW);
1052
1053	if (!nr_addr_ranges)
1054		add_addr_range(0, st->st_size / page_size);
1055
1056	for (i = 0; i < nr_addr_ranges; i++)
1057		walk_file_range(name, fd, opt_offset[i] * page_size,
1058				(opt_offset[i] + opt_size[i]) * page_size);
1059
1060	close(fd);
1061}
1062
1063int walk_tree(const char *name, const struct stat *st, int type, struct FTW *f)
1064{
1065	(void)f;
1066	switch (type) {
1067	case FTW_F:
1068		if (S_ISREG(st->st_mode))
1069			walk_file(name, st);
1070		break;
1071	case FTW_DNR:
1072		fprintf(stderr, "cannot read dir: %s\n", name);
1073		break;
1074	}
1075	return 0;
1076}
1077
1078struct stat st;
1079
1080static void walk_page_cache(void)
1081{
1082	kpageflags_fd = checked_open(opt_kpageflags, O_RDONLY);
1083	pagemap_fd = checked_open("/proc/self/pagemap", O_RDONLY);
1084	sigaction(SIGBUS, &sigbus_action, NULL);
1085
1086	if (stat(opt_file, &st))
1087		fatal("stat failed: %s\n", opt_file);
1088
1089	if (S_ISREG(st.st_mode)) {
1090		walk_file(opt_file, &st);
1091	} else if (S_ISDIR(st.st_mode)) {
1092		/* do not follow symlinks and mountpoints */
1093		if (nftw(opt_file, walk_tree, 64, FTW_MOUNT | FTW_PHYS) < 0)
1094			fatal("nftw failed: %s\n", opt_file);
1095	} else
1096		fatal("unhandled file type: %s\n", opt_file);
1097
1098	close(kpageflags_fd);
1099	close(pagemap_fd);
1100	signal(SIGBUS, SIG_DFL);
1101}
1102
1103static void parse_file(const char *name)
1104{
1105	opt_file = name;
1106}
1107
1108static void parse_cgroup(const char *path)
1109{
1110	if (path[0] == '@') {
1111		opt_cgroup = parse_number(path + 1);
1112		return;
1113	}
1114
1115	struct stat st;
1116
1117	if (stat(path, &st))
1118		fatal("stat failed: %s: %m\n", path);
1119
1120	if (!S_ISDIR(st.st_mode))
1121		fatal("cgroup supposed to be a directory: %s\n", path);
1122
1123	opt_cgroup = st.st_ino;
1124}
1125
1126static void parse_addr_range(const char *optarg)
1127{
1128	unsigned long offset;
1129	unsigned long size;
1130	char *p;
1131
1132	p = strchr(optarg, ',');
1133	if (!p)
1134		p = strchr(optarg, '+');
1135
1136	if (p == optarg) {
1137		offset = 0;
1138		size   = parse_number(p + 1);
1139	} else if (p) {
1140		offset = parse_number(optarg);
1141		if (p[1] == '\0')
1142			size = ULONG_MAX;
1143		else {
1144			size = parse_number(p + 1);
1145			if (*p == ',') {
1146				if (size < offset)
1147					fatal("invalid range: %lu,%lu\n",
1148							offset, size);
1149				size -= offset;
1150			}
1151		}
1152	} else {
1153		offset = parse_number(optarg);
1154		size   = 1;
1155	}
1156
1157	add_addr_range(offset, size);
1158}
1159
1160static void add_bits_filter(uint64_t mask, uint64_t bits)
1161{
1162	if (nr_bit_filters >= MAX_BIT_FILTERS)
1163		fatal("too much bit filters\n");
1164
1165	opt_mask[nr_bit_filters] = mask;
1166	opt_bits[nr_bit_filters] = bits;
1167	nr_bit_filters++;
1168}
1169
1170static uint64_t parse_flag_name(const char *str, int len)
1171{
1172	size_t i;
1173
1174	if (!*str || !len)
1175		return 0;
1176
1177	if (len <= 8 && !strncmp(str, "compound", len))
1178		return BITS_COMPOUND;
1179
1180	for (i = 0; i < ARRAY_SIZE(page_flag_names); i++) {
1181		if (!page_flag_names[i])
1182			continue;
1183		if (!strncmp(str, page_flag_names[i] + 2, len))
1184			return 1ULL << i;
1185	}
1186
1187	return parse_number(str);
1188}
1189
1190static uint64_t parse_flag_names(const char *str, int all)
1191{
1192	const char *p    = str;
1193	uint64_t   flags = 0;
1194
1195	while (1) {
1196		if (*p == ',' || *p == '=' || *p == '\0') {
1197			if ((*str != '~') || (*str == '~' && all && *++str))
1198				flags |= parse_flag_name(str, p - str);
1199			if (*p != ',')
1200				break;
1201			str = p + 1;
1202		}
1203		p++;
1204	}
1205
1206	return flags;
1207}
1208
1209static void parse_bits_mask(const char *optarg)
1210{
1211	uint64_t mask;
1212	uint64_t bits;
1213	const char *p;
1214
1215	p = strchr(optarg, '=');
1216	if (p == optarg) {
1217		mask = KPF_ALL_BITS;
1218		bits = parse_flag_names(p + 1, 0);
1219	} else if (p) {
1220		mask = parse_flag_names(optarg, 0);
1221		bits = parse_flag_names(p + 1, 0);
1222	} else if (strchr(optarg, '~')) {
1223		mask = parse_flag_names(optarg, 1);
1224		bits = parse_flag_names(optarg, 0);
1225	} else {
1226		mask = parse_flag_names(optarg, 0);
1227		bits = KPF_ALL_BITS;
1228	}
1229
1230	add_bits_filter(mask, bits);
1231}
1232
1233static void parse_kpageflags(const char *name)
1234{
1235	opt_kpageflags = name;
1236}
1237
1238static void describe_flags(const char *optarg)
1239{
1240	uint64_t flags = parse_flag_names(optarg, 0);
1241
1242	printf("0x%016llx\t%s\t%s\n",
1243		(unsigned long long)flags,
1244		page_flag_name(flags),
1245		page_flag_longname(flags));
1246}
1247
1248static const struct option opts[] = {
1249	{ "raw"       , 0, NULL, 'r' },
1250	{ "pid"       , 1, NULL, 'p' },
1251	{ "file"      , 1, NULL, 'f' },
1252	{ "addr"      , 1, NULL, 'a' },
1253	{ "bits"      , 1, NULL, 'b' },
1254	{ "cgroup"    , 1, NULL, 'c' },
1255	{ "describe"  , 1, NULL, 'd' },
1256	{ "mark-idle" , 0, NULL, 'i' },
1257	{ "list"      , 0, NULL, 'l' },
1258	{ "list-each" , 0, NULL, 'L' },
1259	{ "list-cgroup", 0, NULL, 'C' },
1260	{ "list-mapcnt", 0, NULL, 'M' },
1261	{ "no-summary", 0, NULL, 'N' },
1262	{ "hwpoison"  , 0, NULL, 'X' },
1263	{ "unpoison"  , 0, NULL, 'x' },
1264	{ "kpageflags", 0, NULL, 'F' },
1265	{ "help"      , 0, NULL, 'h' },
1266	{ NULL        , 0, NULL, 0 }
1267};
1268
1269int main(int argc, char *argv[])
1270{
1271	int c;
1272
1273	page_size = getpagesize();
1274
1275	while ((c = getopt_long(argc, argv,
1276				"rp:f:a:b:d:c:CilLMNXxF:h",
1277				opts, NULL)) != -1) {
1278		switch (c) {
1279		case 'r':
1280			opt_raw = 1;
1281			break;
1282		case 'p':
1283			parse_pid(optarg);
1284			break;
1285		case 'f':
1286			parse_file(optarg);
1287			break;
1288		case 'a':
1289			parse_addr_range(optarg);
1290			break;
1291		case 'b':
1292			parse_bits_mask(optarg);
1293			break;
1294		case 'c':
1295			parse_cgroup(optarg);
1296			break;
1297		case 'C':
1298			opt_list_cgroup = 1;
1299			break;
1300		case 'd':
1301			describe_flags(optarg);
1302			exit(0);
1303		case 'i':
1304			opt_mark_idle = 1;
1305			break;
1306		case 'l':
1307			opt_list = 1;
1308			break;
1309		case 'L':
1310			opt_list = 2;
1311			break;
1312		case 'M':
1313			opt_list_mapcnt = 1;
1314			break;
1315		case 'N':
1316			opt_no_summary = 1;
1317			break;
1318		case 'X':
1319			opt_hwpoison = 1;
1320			prepare_hwpoison_fd();
1321			break;
1322		case 'x':
1323			opt_unpoison = 1;
1324			prepare_hwpoison_fd();
1325			break;
1326		case 'F':
1327			parse_kpageflags(optarg);
1328			break;
1329		case 'h':
1330			usage();
1331			exit(0);
1332		default:
1333			usage();
1334			exit(1);
1335		}
1336	}
1337
1338	if (!opt_kpageflags)
1339		opt_kpageflags = PROC_KPAGEFLAGS;
1340
1341	if (opt_cgroup || opt_list_cgroup)
1342		kpagecgroup_fd = checked_open(PROC_KPAGECGROUP, O_RDONLY);
1343
1344	if (opt_list && opt_list_mapcnt)
1345		kpagecount_fd = checked_open(PROC_KPAGECOUNT, O_RDONLY);
1346
1347	if (opt_mark_idle)
1348		page_idle_fd = checked_open(SYS_KERNEL_MM_PAGE_IDLE, O_RDWR);
1349
1350	if (opt_list && opt_pid)
1351		printf("voffset\t");
1352	if (opt_list && opt_file)
1353		printf("foffset\t");
1354	if (opt_list && opt_list_cgroup)
1355		printf("cgroup\t");
1356	if (opt_list && opt_list_mapcnt)
1357		printf("map-cnt\t");
1358
1359	if (opt_list == 1)
1360		printf("offset\tlen\tflags\n");
1361	if (opt_list == 2)
1362		printf("offset\tflags\n");
1363
1364	if (opt_file)
1365		walk_page_cache();
1366	else
1367		walk_addr_ranges();
1368
1369	if (opt_list == 1)
1370		flush_page_range();
1371
1372	if (opt_no_summary)
1373		return 0;
1374
1375	if (opt_list)
1376		printf("\n\n");
1377
1378	if (opt_file) {
1379		show_file(opt_file, &st);
1380		printf("\n");
1381	}
1382
1383	show_summary();
1384
1385	if (opt_list_mapcnt)
1386		close(kpagecount_fd);
1387
1388	if (page_idle_fd >= 0)
1389		close(page_idle_fd);
1390
1391	return 0;
1392}