diff options
Diffstat (limited to 'tools/vm/page-types.c')
| -rw-r--r-- | tools/vm/page-types.c | 1176 |
1 files changed, 1176 insertions, 0 deletions
diff --git a/tools/vm/page-types.c b/tools/vm/page-types.c new file mode 100644 index 00000000000..c4d6d2e20e0 --- /dev/null +++ b/tools/vm/page-types.c @@ -0,0 +1,1176 @@ +/* + * 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_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; +} |