/*
* page-types: Tool for querying page flags
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; version 2.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should find a copy of v2 of the GNU General Public License somewhere on
* your Linux system; if not, write to the Free Software Foundation, Inc., 59
* Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*
* Copyright (C) 2009 Intel corporation
*
* Authors: Wu Fengguang <fengguang.wu@intel.com>
*/
#define _FILE_OFFSET_BITS 64
#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdint.h>
#include <stdarg.h>
#include <string.h>
#include <getopt.h>
#include <limits.h>
#include <assert.h>
#include <ftw.h>
#include <time.h>
#include <setjmp.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/errno.h>
#include <sys/fcntl.h>
#include <sys/mount.h>
#include <sys/statfs.h>
#include <sys/mman.h>
#include "../../include/uapi/linux/magic.h"
#include "../../include/uapi/linux/kernel-page-flags.h"
#include <api/fs/debugfs.h>
#ifndef MAX_PATH
# define MAX_PATH 256
#endif
#ifndef STR
# define _STR(x) #x
# define STR(x) _STR(x)
#endif
/*
* pagemap kernel ABI bits
*/
#define PM_ENTRY_BYTES sizeof(uint64_t)
#define PM_STATUS_BITS 3
#define PM_STATUS_OFFSET (64 - PM_STATUS_BITS)
#define PM_STATUS_MASK (((1LL << PM_STATUS_BITS) - 1) << PM_STATUS_OFFSET)
#define PM_STATUS(nr) (((nr) << PM_STATUS_OFFSET) & PM_STATUS_MASK)
#define PM_PSHIFT_BITS 6
#define PM_PSHIFT_OFFSET (PM_STATUS_OFFSET - PM_PSHIFT_BITS)
#define PM_PSHIFT_MASK (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET)
#define __PM_PSHIFT(x) (((uint64_t) (x) << PM_PSHIFT_OFFSET) & PM_PSHIFT_MASK)
#define PM_PFRAME_MASK ((1LL << PM_PSHIFT_OFFSET) - 1)
#define PM_PFRAME(x) ((x) & PM_PFRAME_MASK)
#define __PM_SOFT_DIRTY (1LL)
#define PM_PRESENT PM_STATUS(4LL)
#define PM_SWAP PM_STATUS(2LL)
#define PM_SOFT_DIRTY __PM_PSHIFT(__PM_SOFT_DIRTY)
/*
* kernel page flags
*/
#define KPF_BYTES 8
#define PROC_KPAGEFLAGS "/proc/kpageflags"
/* [32-] kernel hacking assistances */
#define KPF_RESERVED 32
#define KPF_MLOCKED 33
#define KPF_MAPPEDTODISK 34
#define KPF_PRIVATE 35
#define KPF_PRIVATE_2 36
#define KPF_OWNER_PRIVATE 37
#define KPF_ARCH 38
#define KPF_UNCACHED 39
#define KPF_SOFTDIRTY 40
/* [48-] take some arbitrary free slots for expanding overloaded flags
* not part of kernel API
*/
#define KPF_READAHEAD 48
#define KPF_SLOB_FREE 49
#define KPF_SLUB_FROZEN 50
#define KPF_SLUB_DEBUG 51
#define KPF_ALL_BITS ((uint64_t)~0ULL)
#define KPF_HACKERS_BITS (0xffffULL << 32)
#define KPF_OVERLOADED_BITS (0xffffULL << 48)
#define BIT(name) (1ULL << KPF_##name)
#define BITS_COMPOUND (BIT(COMPOUND_HEAD) | BIT(COMPOUND_TAIL))
static const char * const page_flag_names[] = {
[KPF_LOCKED] = "L:locked",
[KPF_ERROR] = "E:error",
[KPF_REFERENCED] = "R:referenced",
[KPF_UPTODATE] = "U:uptodate",
[KPF_DIRTY] = "D:dirty",
[KPF_LRU] = "l:lru",
[KPF_ACTIVE] = "A:active",
[KPF_SLAB] = "S:slab",
[KPF_WRITEBACK] = "W:writeback",
[KPF_RECLAIM] = "I:reclaim",
[KPF_BUDDY] = "B:buddy",
[KPF_MMAP] = "M:mmap",
[KPF_ANON] = "a:anonymous",
[KPF_SWAPCACHE] = "s:swapcache",
[KPF_SWAPBACKED] = "b:swapbacked",
[KPF_COMPOUND_HEAD] = "H:compound_head",
[KPF_COMPOUND_TAIL] = "T:compound_tail",
[KPF_HUGE] = "G:huge",
[KPF_UNEVICTABLE] = "u:unevictable",
[KPF_HWPOISON] = "X:hwpoison",
[KPF_NOPAGE] = "n:nopage",
[KPF_KSM] = "x:ksm",
[KPF_THP] = "t:thp",
[KPF_BALLOON] = "o:balloon",
[KPF_ZERO_PAGE] = "z:zero_page",
[KPF_RESERVED] = "r:reserved",
[KPF_MLOCKED] = "m:mlocked",
[KPF_MAPPEDTODISK] = "d:mappedtodisk",
[KPF_PRIVATE] = "P:private",
[KPF_PRIVATE_2] = "p:private_2",
[KPF_OWNER_PRIVATE] = "O:owner_private",
[KPF_ARCH] = "h:arch",
[KPF_UNCACHED] = "c:uncached",
[KPF_SOFTDIRTY] = "f:softdirty",
[KPF_READAHEAD] = "I:readahead",
[KPF_SLOB_FREE] = "P:slob_free",
[KPF_SLUB_FROZEN] = "A:slub_frozen",
[KPF_SLUB_DEBUG] = "E:slub_debug",
};
static const char * const debugfs_known_mountpoints[] = {
"/sys/kernel/debug",
"/debug",
0,
};
/*
* data structures
*/
static int opt_raw; /* for kernel developers */
static int opt_list; /* list pages (in ranges) */
static int opt_no_summary; /* don't show summary */
static pid_t opt_pid; /* process to walk */
const char * opt_file;
#define MAX_ADDR_RANGES 1024
static int nr_addr_ranges;
static unsigned long opt_offset[MAX_ADDR_RANGES];
static unsigned long opt_size[MAX_ADDR_RANGES];
#define MAX_VMAS 10240
static int nr_vmas;
static unsigned long pg_start[MAX_VMAS];
static unsigned long pg_end[MAX_VMAS];
#define MAX_BIT_FILTERS 64
static int nr_bit_filters;
static uint64_t opt_mask[MAX_BIT_FILTERS];
static uint64_t opt_bits[MAX_BIT_FILTERS];
static int page_size;
static int pagemap_fd;
static int kpageflags_fd;
static int opt_hwpoison;
static int opt_unpoison;
static char *hwpoison_debug_fs;
static int hwpoison_inject_fd;
static int hwpoison_forget_fd;
#define HASH_SHIFT 13
#define HASH_SIZE (1 << HASH_SHIFT)
#define HASH_MASK (HASH_SIZE - 1)
#define HASH_KEY(flags) (flags & HASH_MASK)
static unsigned long total_pages;
static unsigned long nr_pages[HASH_SIZE];
static uint64_t page_flags[HASH_SIZE];
/*
* helper functions
*/
#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
#define min_t(type, x, y) ({ \
type __min1 = (x); \
type __min2 = (y); \
__min1 < __min2 ? __min1 : __min2; })
#define max_t(type, x, y) ({ \
type __max1 = (x); \
type __max2 = (y); \
__max1 > __max2 ? __max1 : __max2; })
static unsigned long pages2mb(unsigned long pages)
{
return (pages * page_size) >> 20;
}
static void fatal(const char *x, ...)
{
va_list ap;
va_start(ap, x);
vfprintf(stderr, x, ap);
va_end(ap);
exit(EXIT_FAILURE);
}
static int checked_open(const char *pathname, int flags)
{
int fd = open(pathname, flags);
if (fd < 0) {
perror(pathname);
exit(EXIT_FAILURE);
}
return fd;
}
/*
* pagemap/kpageflags routines
*/
static unsigned long do_u64_read(int fd, char *name,
uint64_t *buf,
unsigned long index,
unsigned long count)
{
long bytes;
if (index > ULONG_MAX / 8)
fatal("index overflow: %lu\n", index);
bytes = pread(fd, buf, count * 8, (off_t)index * 8);
if (bytes < 0) {
perror(name);
exit(EXIT_FAILURE);
}
if (bytes % 8)
fatal("partial read: %lu bytes\n", bytes);
return bytes / 8;
}
static unsigned long kpageflags_read(uint64_t *buf,
unsigned long index,
unsigned long pages)
{
return do_u64_read(kpageflags_fd, PROC_KPAGEFLAGS, buf, index, pages);
}
static unsigned long pagemap_read(uint64_t *buf,
unsigned long index,
unsigned long pages)
{
return do_u64_read(pagemap_fd, "/proc/pid/pagemap", buf, index, pages);
}
static unsigned long pagemap_pfn(uint64_t val)
{
unsigned long pfn;
if (val & PM_PRESENT)
pfn = PM_PFRAME(val);
else
pfn = 0;
return pfn;
}
/*
* page flag names
*/
static char *page_flag_name(uint64_t flags)
{
static char buf[65];
int present;
size_t i, j;
for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
present = (flags >> i) & 1;
if (!page_flag_names[i]) {
if (present)
fatal("unknown flag bit %d\n", i);
continue;
}
buf[j++] = present ? page_flag_names[i][0] : '_';
}
return buf;
}
static char *page_flag_longname(uint64_t flags)
{
static char buf[1024];
size_t i, n;
for (i = 0, n = 0; i < ARRAY_SIZE(page_flag_names); i++) {
if (!page_flag_names[i])
continue;
if ((flags >> i) & 1)
n += snprintf(buf + n, sizeof(buf) - n, "%s,",
page_flag_names[i] + 2);
}
if (n)
n--;
buf[n] = '\0';
return buf;
}
/*
* page list and summary
*/
static void show_page_range(unsigned long voffset, unsigned long offset,
unsigned long size, uint64_t flags)
{
static uint64_t flags0;
static unsigned long voff;
static unsigned long index;
static unsigned long count;
if (flags == flags0 && offset == index + count &&
size && voffset == voff + count) {
count += size;
return;
}
if (count) {
if (opt_pid)
printf("%lx\t", voff);
if (opt_file)
printf("%lu\t", voff);
printf("%lx\t%lx\t%s\n",
index, count, page_flag_name(flags0));
}
flags0 = flags;
index = offset;
voff = voffset;
count = size;
}
static void flush_page_range(void)
{
show_page_range(0, 0, 0, 0);
}
static void show_page(unsigned long voffset,
unsigned long offset, uint64_t flags)
{
if (opt_pid)
printf("%lx\t", voffset);
if (opt_file)
printf("%lu\t", voffset);
printf("%lx\t%s\n", offset, page_flag_name(flags));
}
static void show_summary(void)
{
size_t i;
printf(" flags\tpage-count MB"
" symbolic-flags\t\t\tlong-symbolic-flags\n");
for (i = 0; i < ARRAY_SIZE(nr_pages); i++) {
if (nr_pages[i])
printf("0x%016llx\t%10lu %8lu %s\t%s\n",
(unsigned long long)page_flags[i],
nr_pages[i],
pages2mb(nr_pages[i]),
page_flag_name(page_flags[i]),
page_flag_longname(page_flags[i]));
}
printf(" total\t%10lu %8lu\n",
total_pages, pages2mb(total_pages));
}
/*
* page flag filters
*/
static int bit_mask_ok(uint64_t flags)
{
int i;
for (i = 0; i < nr_bit_filters; i++) {
if (opt_bits[i] == KPF_ALL_BITS) {
if ((flags & opt_mask[i]) == 0)
return 0;
} else {
if ((flags & opt_mask[i]) != opt_bits[i])
return 0;
}
}
return 1;
}
static uint64_t expand_overloaded_flags(uint64_t flags, uint64_t pme)
{
/* SLOB/SLUB overload several page flags */
if (flags & BIT(SLAB)) {
if (flags & BIT(PRIVATE))
flags ^= BIT(PRIVATE) | BIT(SLOB_FREE);
if (flags & BIT(ACTIVE))
flags ^= BIT(ACTIVE) | BIT(SLUB_FROZEN);
if (flags & BIT(ERROR))
flags ^= BIT(ERROR) | BIT(SLUB_DEBUG);
}
/* PG_reclaim is overloaded as PG_readahead in the read path */
if ((flags & (BIT(RECLAIM) | BIT(WRITEBACK))) == BIT(RECLAIM))
flags ^= BIT(RECLAIM) | BIT(READAHEAD);
if (pme & PM_SOFT_DIRTY)
flags |= BIT(SOFTDIRTY);
return flags;
}
static uint64_t well_known_flags(uint64_t flags)
{
/* hide flags intended only for kernel hacker */
flags &= ~KPF_HACKERS_BITS;
/* hide non-hugeTLB compound pages */
if ((flags & BITS_COMPOUND) && !(flags & BIT(HUGE)))
flags &= ~BITS_COMPOUND;
return flags;
}
static uint64_t kpageflags_flags(uint64_t flags, uint64_t pme)
{
if (opt_raw)
flags = expand_overloaded_flags(flags, pme);
else
flags = well_known_flags(flags);
return flags;
}
/*
* page actions
*/
static void prepare_hwpoison_fd(void)
{
char buf[MAX_PATH + 1];
hwpoison_debug_fs = debugfs_mount(NULL);
if (!hwpoison_debug_fs) {
perror("mount debugfs");
exit(EXIT_FAILURE);
}
if (opt_hwpoison && !hwpoison_inject_fd) {
snprintf(buf, MAX_PATH, "%s/hwpoison/corrupt-pfn",
hwpoison_debug_fs);
hwpoison_inject_fd = checked_open(buf, O_WRONLY);
}
if (opt_unpoison && !hwpoison_forget_fd) {
snprintf(buf, MAX_PATH, "%s/hwpoison/unpoison-pfn",
hwpoison_debug_fs);
hwpoison_forget_fd = checked_open(buf, O_WRONLY);
}
}
static int hwpoison_page(unsigned long offset)
{
char buf[100];
int len;
len = sprintf(buf, "0x%lx\n", offset);
len = write(hwpoison_inject_fd, buf, len);
if (len < 0) {
perror("hwpoison inject");
return len;
}
return 0;
}
static int unpoison_page(unsigned long offset)
{
char buf[100];
int len;
len = sprintf(buf, "0x%lx\n", offset);
len = write(hwpoison_forget_fd, buf, len);
if (len < 0) {
perror("hwpoison forget");
return len;
}
return 0;
}
/*
* page frame walker
*/
static size_t hash_slot(uint64_t flags)
{
size_t k = HASH_KEY(flags);
size_t i;
/* Explicitly reserve slot 0 for flags 0: the following logic
* cannot distinguish an unoccupied slot from slot (flags==0).
*/
if (flags == 0)
return 0;
/* search through the remaining (HASH_SIZE-1) slots */
for (i = 1; i < ARRAY_SIZE(page_flags); i++, k++) {
if (!k || k >= ARRAY_SIZE(page_flags))
k = 1;
if (page_flags[k] == 0) {
page_flags[k] = flags;
return k;
}
if (page_flags[k] == flags)
return k;
}
fatal("hash table full: bump up HASH_SHIFT?\n");
exit(EXIT_FAILURE);
}
static void add_page(unsigned long voffset,
unsigned long offset, uint64_t flags, uint64_t pme)
{
flags = kpageflags_flags(flags, pme);
if (!bit_mask_ok(flags))
return;
if (opt_hwpoison)
hwpoison_page(offset);
if (opt_unpoison)
unpoison_page(offset);
if (opt_list == 1)
show_page_range(voffset, offset, 1, flags);
else if (opt_list == 2)
show_page(voffset, offset, flags);
nr_pages[hash_slot(flags)]++;
total_pages++;
}
#define KPAGEFLAGS_BATCH (64 << 10) /* 64k pages */
static void walk_pfn(unsigned long voffset,
unsigned long index,
unsigned long count,
uint64_t pme)
{
uint64_t buf[KPAGEFLAGS_BATCH];
unsigned long batch;
unsigned long pages;
unsigned long i;
while (count) {
batch = min_t(unsigned long, count, KPAGEFLAGS_BATCH);
pages = kpageflags_read(buf, index, batch);
if (pages == 0)
break;
for (i = 0; i < pages; i++)
add_page(voffset + i, index + i, buf[i], pme);
index += pages;
count -= pages;
}
}
#define PAGEMAP_BATCH (64 << 10)
static void walk_vma(unsigned long index, unsigned long count)
{
uint64_t buf[PAGEMAP_BATCH];
unsigned long batch;
unsigned long pages;
unsigned long pfn;
unsigned long i;
while (count) {
batch = min_t(unsigned long, count, PAGEMAP_BATCH);
pages = pagemap_read(buf, index, batch);
if (pages == 0)
break;
for (i = 0; i < pages; i++) {
pfn = pagemap_pfn(buf[i]);
if (pfn)
walk_pfn(index + i, pfn, 1, buf[i]);
}
index += pages;
count -= pages;
}
}
static void walk_task(unsigned long index, unsigned long count)
{
const unsigned long end = index + count;
unsigned long start;
int i = 0;
while (index < end) {
while (pg_end[i] <= index)
if (++i >= nr_vmas)
return;
if (pg_start[i] >= end)
return;
start = max_t(unsigned long, pg_start[i], index);
index = min_t(unsigned long, pg_end[i], end);
assert(start < index);
walk_vma(start, index - start);
}
}
static void add_addr_range(unsigned long offset, unsigned long size)
{
if (nr_addr_ranges >= MAX_ADDR_RANGES)
fatal("too many addr ranges\n");
opt_offset[nr_addr_ranges] = offset;
opt_size[nr_addr_ranges] = min_t(unsigned long, size, ULONG_MAX-offset);
nr_addr_ranges++;
}
static void walk_addr_ranges(void)
{
int i;
kpageflags_fd = checked_open(PROC_KPAGEFLAGS, O_RDONLY);
if (!nr_addr_ranges)
add_addr_range(0, ULONG_MAX);
for (i = 0; i < nr_addr_ranges; i++)
if (!opt_pid)
walk_pfn(opt_offset[i], opt_offset[i], opt_size[i], 0);
else
walk_task(opt_offset[i], opt_size[i]);
close(kpageflags_fd);
}
/*
* user interface
*/
static const char *page_flag_type(uint64_t flag)
{
if (flag & KPF_HACKERS_BITS)
return "(r)";
if (flag & KPF_OVERLOADED_BITS)
return "(o)";
return " ";
}
static void usage(void)
{
size_t i, j;
printf(
"page-types [options]\n"
" -r|--raw Raw mode, for kernel developers\n"
" -d|--describe flags Describe flags\n"
" -a|--addr addr-spec Walk a range of pages\n"
" -b|--bits bits-spec Walk pages with specified bits\n"
" -p|--pid pid Walk process address space\n"
" -f|--file filename Walk file address space\n"
" -l|--list Show page details in ranges\n"
" -L|--list-each Show page details one by one\n"
" -N|--no-summary Don't show summary info\n"
" -X|--hwpoison hwpoison pages\n"
" -x|--unpoison unpoison pages\n"
" -h|--help Show this usage message\n"
"flags:\n"
" 0x10 bitfield format, e.g.\n"
" anon bit-name, e.g.\n"
" 0x10,anon comma-separated list, e.g.\n"
"addr-spec:\n"
" N one page at offset N (unit: pages)\n"
" N+M pages range from N to N+M-1\n"
" N,M pages range from N to M-1\n"
" N, pages range from N to end\n"
" ,M pages range from 0 to M-1\n"
"bits-spec:\n"
" bit1,bit2 (flags & (bit1|bit2)) != 0\n"
" bit1,bit2=bit1 (flags & (bit1|bit2)) == bit1\n"
" bit1,~bit2 (flags & (bit1|bit2)) == bit1\n"
" =bit1,bit2 flags == (bit1|bit2)\n"
"bit-names:\n"
);
for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) {
if (!page_flag_names[i])
continue;
printf("%16s%s", page_flag_names[i] + 2,
page_flag_type(1ULL << i));
if (++j > 3) {
j = 0;
putchar('\n');
}
}
printf("\n "
"(r) raw mode bits (o) overloaded bits\n");
}
static unsigned long long parse_number(const char *str)
{
unsigned long long n;
n = strtoll(str, NULL, 0);
if (n == 0 && str[0] != '0')
fatal("invalid name or number: %s\n", str);
return n;
}
static void parse_pid(const char *str)
{
FILE *file;
char buf[5000];
opt_pid = parse_number(str);
sprintf(buf, "/proc/%d/pagemap", opt_pid);
pagemap_fd = checked_open(buf, O_RDONLY);
sprintf(buf, "/proc/%d/maps", opt_pid);
file = fopen(buf, "r");
if (!file) {
perror(buf);
exit(EXIT_FAILURE);
}
while (fgets(buf, sizeof(buf), file) != NULL) {
unsigned long vm_start;
unsigned long vm_end;
unsigned long long pgoff;
int major, minor;
char r, w, x, s;
unsigned long ino;
int n;
n = sscanf(buf, "%lx-%lx %c%c%c%c %llx %x:%x %lu",
&vm_start,
&vm_end,
&r, &w, &x, &s,
&pgoff,
&major, &minor,
&ino);
if (n < 10) {
fprintf(stderr, "unexpected line: %s\n", buf);
continue;
}
pg_start[nr_vmas] = vm_start / page_size;
pg_end[nr_vmas] = vm_end / page_size;
if (++nr_vmas >= MAX_VMAS) {
fprintf(stderr, "too many VMAs\n");
break;
}
}
fclose(file);
}
static void show_file(const char *name, const struct stat *st)
{
unsigned long long size = st->st_size;
char atime[64], mtime[64];
long now = time(NULL);
printf("%s\tInode: %u\tSize: %llu (%llu pages)\n",
name, (unsigned)st->st_ino,
size, (size + page_size - 1) / page_size);
strftime(atime, sizeof(atime), "%c", localtime(&st->st_atime));
strftime(mtime, sizeof(mtime), "%c", localtime(&st->st_mtime));
printf("Modify: %s (%ld seconds ago)\nAccess: %s (%ld seconds ago)\n",
mtime, now - st->st_mtime,
atime, now - st->st_atime);
}
static sigjmp_buf sigbus_jmp;
static void * volatile sigbus_addr;
static void sigbus_handler(int sig, siginfo_t *info, void *ucontex)
{
(void)sig;
(void)ucontex;
sigbus_addr = info ? info->si_addr : NULL;
siglongjmp(sigbus_jmp, 1);
}
static struct sigaction sigbus_action = {
.sa_sigaction = sigbus_handler,
.sa_flags = SA_SIGINFO,
};
static void walk_file(const char *name, const struct stat *st)
{
uint8_t vec[PAGEMAP_BATCH];
uint64_t buf[PAGEMAP_BATCH], flags;
unsigned long nr_pages, pfn, i;
off_t off, end = st->st_size;
int fd;
ssize_t len;
void *ptr;
int first = 1;
fd = checked_open(name, O_RDONLY|O_NOATIME|O_NOFOLLOW);
for (off = 0; off < end; off += len) {
nr_pages = (end - off + page_size - 1) / page_size;
if (nr_pages > PAGEMAP_BATCH)
nr_pages = PAGEMAP_BATCH;
len = nr_pages * page_size;
ptr = mmap(NULL, len, PROT_READ, MAP_SHARED, fd, off);
if (ptr == MAP_FAILED)
fatal("mmap failed: %s", name);
/* determine cached pages */
if (mincore(ptr, len, vec))
fatal("mincore failed: %s", name);
/* turn off readahead */
if (madvise(ptr, len, MADV_RANDOM))
fatal("madvice failed: %s", name);
if (sigsetjmp(sigbus_jmp, 1)) {
end = off + sigbus_addr ? sigbus_addr - ptr : 0;
fprintf(stderr, "got sigbus at offset %lld: %s\n",
(long long)end, name);
goto got_sigbus;
}
/* populate ptes */
for (i = 0; i < nr_pages ; i++) {
if (vec[i] & 1)
(void)*(volatile int *)(ptr + i * page_size);
}
got_sigbus:
/* turn off harvesting reference bits */
if (madvise(ptr, len, MADV_SEQUENTIAL))
fatal("madvice failed: %s", name);
if (pagemap_read(buf, (unsigned long)ptr / page_size,
nr_pages) != nr_pages)
fatal("cannot read pagemap");
munmap(ptr, len);
for (i = 0; i < nr_pages; i++) {
pfn = pagemap_pfn(buf[i]);
if (!pfn)
continue;
if (!kpageflags_read(&flags, pfn, 1))
continue;
if (first && opt_list) {
first = 0;
flush_page_range();
show_file(name, st);
}
add_page(off / page_size + i, pfn, flags, buf[i]);
}
}
close(fd);
}
int walk_tree(const char *name, const struct stat *st, int type, struct FTW *f)
{
(void)f;
switch (type) {
case FTW_F:
if (S_ISREG(st->st_mode))
walk_file(name, st);
break;
case FTW_DNR:
fprintf(stderr, "cannot read dir: %s\n", name);
break;
}
return 0;
}
static void walk_page_cache(void)
{
struct stat st;
kpageflags_fd = checked_open(PROC_KPAGEFLAGS, O_RDONLY);
pagemap_fd = checked_open("/proc/self/pagemap", O_RDONLY);
sigaction(SIGBUS, &sigbus_action, NULL);
if (stat(opt_file, &st))
fatal("stat failed: %s\n", opt_file);
if (S_ISREG(st.st_mode)) {
walk_file(opt_file, &st);
} else if (S_ISDIR(st.st_mode)) {
/* do not follow symlinks and mountpoints */
if (nftw(opt_file, walk_tree, 64, FTW_MOUNT | FTW_PHYS) < 0)
fatal("nftw failed: %s\n", opt_file);
} else
fatal("unhandled file type: %s\n", opt_file);
close(kpageflags_fd);
close(pagemap_fd);
signal(SIGBUS, SIG_DFL);
}
static void parse_file(const char *name)
{
opt_file = name;
}
static void parse_addr_range(const char *optarg)
{
unsigned long offset;
unsigned long size;
char *p;
p = strchr(optarg, ',');
if (!p)
p = strchr(optarg, '+');
if (p == optarg) {
offset = 0;
size = parse_number(p + 1);
} else if (p) {
offset = parse_number(optarg);
if (p[1] == '\0')
size = ULONG_MAX;
else {
size = parse_number(p + 1);
if (*p == ',') {
if (size < offset)
fatal("invalid range: %lu,%lu\n",
offset, size);
size -= offset;
}
}
} else {
offset = parse_number(optarg);
size = 1;
}
add_addr_range(offset, size);
}
static void add_bits_filter(uint64_t mask, uint64_t bits)
{
if (nr_bit_filters >= MAX_BIT_FILTERS)
fatal("too much bit filters\n");
opt_mask[nr_bit_filters] = mask;
opt_bits[nr_bit_filters] = bits;
nr_bit_filters++;
}
static uint64_t parse_flag_name(const char *str, int len)
{
size_t i;
if (!*str || !len)
return 0;
if (len <= 8 && !strncmp(str, "compound", len))
return BITS_COMPOUND;
for (i = 0; i < ARRAY_SIZE(page_flag_names); i++) {
if (!page_flag_names[i])
continue;
if (!strncmp(str, page_flag_names[i] + 2, len))
return 1ULL << i;
}
return parse_number(str);
}
static uint64_t parse_flag_names(const char *str, int all)
{
const char *p = str;
uint64_t flags = 0;
while (1) {
if (*p == ',' || *p == '=' || *p == '\0') {
if ((*str != '~') || (*str == '~' && all && *++str))
flags |= parse_flag_name(str, p - str);
if (*p != ',')
break;
str = p + 1;
}
p++;
}
return flags;
}
static void parse_bits_mask(const char *optarg)
{
uint64_t mask;
uint64_t bits;
const char *p;
p = strchr(optarg, '=');
if (p == optarg) {
mask = KPF_ALL_BITS;
bits = parse_flag_names(p + 1, 0);
} else if (p) {
mask = parse_flag_names(optarg, 0);
bits = parse_flag_names(p + 1, 0);
} else if (strchr(optarg, '~')) {
mask = parse_flag_names(optarg, 1);
bits = parse_flag_names(optarg, 0);
} else {
mask = parse_flag_names(optarg, 0);
bits = KPF_ALL_BITS;
}
add_bits_filter(mask, bits);
}
static void describe_flags(const char *optarg)
{
uint64_t flags = parse_flag_names(optarg, 0);
printf("0x%016llx\t%s\t%s\n",
(unsigned long long)flags,
page_flag_name(flags),
page_flag_longname(flags));
}
static const struct option opts[] = {
{ "raw" , 0, NULL, 'r' },
{ "pid" , 1, NULL, 'p' },
{ "file" , 1, NULL, 'f' },
{ "addr" , 1, NULL, 'a' },
{ "bits" , 1, NULL, 'b' },
{ "describe" , 1, NULL, 'd' },
{ "list" , 0, NULL, 'l' },
{ "list-each" , 0, NULL, 'L' },
{ "no-summary", 0, NULL, 'N' },
{ "hwpoison" , 0, NULL, 'X' },
{ "unpoison" , 0, NULL, 'x' },
{ "help" , 0, NULL, 'h' },
{ NULL , 0, NULL, 0 }
};
int main(int argc, char *argv[])
{
int c;
page_size = getpagesize();
while ((c = getopt_long(argc, argv,
"rp:f:a:b:d:lLNXxh", opts, NULL)) != -1) {
switch (c) {
case 'r':
opt_raw = 1;
break;
case 'p':
parse_pid(optarg);
break;
case 'f':
parse_file(optarg);
break;
case 'a':
parse_addr_range(optarg);
break;
case 'b':
parse_bits_mask(optarg);
break;
case 'd':
describe_flags(optarg);
exit(0);
case 'l':
opt_list = 1;
break;
case 'L':
opt_list = 2;
break;
case 'N':
opt_no_summary = 1;
break;
case 'X':
opt_hwpoison = 1;
prepare_hwpoison_fd();
break;
case 'x':
opt_unpoison = 1;
prepare_hwpoison_fd();
break;
case 'h':
usage();
exit(0);
default:
usage();
exit(1);
}
}
if (opt_list && opt_pid)
printf("voffset\t");
if (opt_list && opt_file)
printf("foffset\t");
if (opt_list == 1)
printf("offset\tlen\tflags\n");
if (opt_list == 2)
printf("offset\tflags\n");
if (opt_file)
walk_page_cache();
else
walk_addr_ranges();
if (opt_list == 1)
flush_page_range();
if (opt_no_summary)
return 0;
if (opt_list)
printf("\n\n");
show_summary();
return 0;
}