diff options
Diffstat (limited to 'Documentation/vm/page-types.c')
-rw-r--r-- | Documentation/vm/page-types.c | 388 |
1 files changed, 332 insertions, 56 deletions
diff --git a/Documentation/vm/page-types.c b/Documentation/vm/page-types.c index 3eda8ea0085..3ec4f2a2258 100644 --- a/Documentation/vm/page-types.c +++ b/Documentation/vm/page-types.c @@ -2,9 +2,13 @@ * page-types: Tool for querying page flags * * Copyright (C) 2009 Intel corporation - * Copyright (C) 2009 Wu Fengguang <fengguang.wu@intel.com> + * + * Authors: Wu Fengguang <fengguang.wu@intel.com> + * + * Released under the General Public License (GPL). */ +#define _LARGEFILE64_SOURCE #include <stdio.h> #include <stdlib.h> #include <unistd.h> @@ -13,12 +17,33 @@ #include <string.h> #include <getopt.h> #include <limits.h> +#include <assert.h> #include <sys/types.h> #include <sys/errno.h> #include <sys/fcntl.h> /* + * 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) (((u64) (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_PRESENT PM_STATUS(4LL) +#define PM_SWAP PM_STATUS(2LL) + + +/* * kernel page flags */ @@ -47,7 +72,9 @@ #define KPF_COMPOUND_TAIL 16 #define KPF_HUGE 17 #define KPF_UNEVICTABLE 18 +#define KPF_HWPOISON 19 #define KPF_NOPAGE 20 +#define KPF_KSM 21 /* [32-] kernel hacking assistances */ #define KPF_RESERVED 32 @@ -94,7 +121,9 @@ static char *page_flag_names[] = { [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_RESERVED] = "r:reserved", [KPF_MLOCKED] = "m:mlocked", @@ -126,6 +155,11 @@ 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]; @@ -133,9 +167,15 @@ static uint64_t opt_bits[MAX_BIT_FILTERS]; static int page_size; -#define PAGES_BATCH (64 << 10) /* 64k pages */ +static int pagemap_fd; static int kpageflags_fd; -static uint64_t kpageflags_buf[KPF_BYTES * PAGES_BATCH]; + +static int opt_hwpoison; +static int opt_unpoison; + +static char *hwpoison_debug_fs = "/debug/hwpoison"; +static int hwpoison_inject_fd; +static int hwpoison_forget_fd; #define HASH_SHIFT 13 #define HASH_SIZE (1 << HASH_SHIFT) @@ -158,6 +198,11 @@ static uint64_t page_flags[HASH_SIZE]; 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; @@ -173,6 +218,74 @@ static void fatal(const char *x, ...) exit(EXIT_FAILURE); } +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); + + if (lseek(fd, index * 8, SEEK_SET) < 0) { + perror(name); + exit(EXIT_FAILURE); + } + + bytes = read(fd, buf, count * 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 @@ -221,29 +334,39 @@ static char *page_flag_longname(uint64_t flags) * page list and summary */ -static void show_page_range(unsigned long offset, uint64_t flags) +static void show_page_range(unsigned long voffset, + unsigned long offset, 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) { + if (flags == flags0 && offset == index + count && + (!opt_pid || voffset == voff + count)) { count++; return; } - if (count) - printf("%lu\t%lu\t%s\n", + if (count) { + if (opt_pid) + printf("%lx\t", voff); + printf("%lx\t%lx\t%s\n", index, count, page_flag_name(flags0)); + } flags0 = flags; index = offset; + voff = voffset; count = 1; } -static void show_page(unsigned long offset, uint64_t flags) +static void show_page(unsigned long voffset, + unsigned long offset, uint64_t flags) { - printf("%lu\t%s\n", offset, page_flag_name(flags)); + if (opt_pid) + printf("%lx\t", voffset); + printf("%lx\t%s\n", offset, page_flag_name(flags)); } static void show_summary(void) @@ -320,6 +443,62 @@ static uint64_t well_known_flags(uint64_t flags) return flags; } +static uint64_t kpageflags_flags(uint64_t flags) +{ + flags = expand_overloaded_flags(flags); + + if (!opt_raw) + flags = well_known_flags(flags); + + return flags; +} + +/* + * page actions + */ + +static void prepare_hwpoison_fd(void) +{ + char buf[100]; + + if (opt_hwpoison && !hwpoison_inject_fd) { + sprintf(buf, "%s/corrupt-pfn", hwpoison_debug_fs); + hwpoison_inject_fd = checked_open(buf, O_WRONLY); + } + + if (opt_unpoison && !hwpoison_forget_fd) { + sprintf(buf, "%s/renew-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 @@ -352,73 +531,124 @@ static int hash_slot(uint64_t flags) exit(EXIT_FAILURE); } -static void add_page(unsigned long offset, uint64_t flags) +static void add_page(unsigned long voffset, + unsigned long offset, uint64_t flags) { - flags = expand_overloaded_flags(flags); - - if (!opt_raw) - flags = well_known_flags(flags); + flags = kpageflags_flags(flags); 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(offset, flags); + show_page_range(voffset, offset, flags); else if (opt_list == 2) - show_page(offset, flags); + show_page(voffset, offset, flags); nr_pages[hash_slot(flags)]++; total_pages++; } -static void walk_pfn(unsigned long index, unsigned long count) +#define KPAGEFLAGS_BATCH (64 << 10) /* 64k pages */ +static void walk_pfn(unsigned long voffset, + unsigned long index, + unsigned long count) { + uint64_t buf[KPAGEFLAGS_BATCH]; unsigned long batch; - unsigned long n; + unsigned long pages; unsigned long i; - if (index > ULONG_MAX / KPF_BYTES) - fatal("index overflow: %lu\n", index); + 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]); + + index += pages; + count -= pages; + } +} - lseek(kpageflags_fd, index * KPF_BYTES, SEEK_SET); +#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, PAGES_BATCH); - n = read(kpageflags_fd, kpageflags_buf, batch * KPF_BYTES); - if (n == 0) + batch = min_t(unsigned long, count, PAGEMAP_BATCH); + pages = pagemap_read(buf, index, batch); + if (pages == 0) break; - if (n < 0) { - perror(PROC_KPAGEFLAGS); - exit(EXIT_FAILURE); + + for (i = 0; i < pages; i++) { + pfn = pagemap_pfn(buf[i]); + if (pfn) + walk_pfn(index + i, pfn, 1); } - if (n % KPF_BYTES != 0) - fatal("partial read: %lu bytes\n", n); - n = n / KPF_BYTES; + 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) { - for (i = 0; i < n; i++) - add_page(index + i, kpageflags_buf[i]); + while (pg_end[i] <= index) + if (++i >= nr_vmas) + return; + if (pg_start[i] >= end) + return; - index += batch; - count -= batch; + 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 = open(PROC_KPAGEFLAGS, O_RDONLY); - if (kpageflags_fd < 0) { - perror(PROC_KPAGEFLAGS); - exit(EXIT_FAILURE); - } + kpageflags_fd = checked_open(PROC_KPAGEFLAGS, O_RDONLY); if (!nr_addr_ranges) - walk_pfn(0, ULONG_MAX); + add_addr_range(0, ULONG_MAX); for (i = 0; i < nr_addr_ranges; i++) - walk_pfn(opt_offset[i], opt_size[i]); + if (!opt_pid) + walk_pfn(0, opt_offset[i], opt_size[i]); + else + walk_task(opt_offset[i], opt_size[i]); close(kpageflags_fd); } @@ -446,20 +676,22 @@ static void usage(void) " -r|--raw Raw mode, for kernel developers\n" " -a|--addr addr-spec Walk a range of pages\n" " -b|--bits bits-spec Walk pages with specified bits\n" -#if 0 /* planned features */ " -p|--pid pid Walk process address space\n" +#if 0 /* planned features */ " -f|--file filename Walk file address space\n" #endif " -l|--list Show page details in ranges\n" " -L|--list-each Show page details one by one\n" " -N|--no-summary Don't show summay info\n" +" -X|--hwpoison hwpoison pages\n" +" -x|--unpoison unpoison pages\n" " -h|--help Show this usage message\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\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" @@ -496,21 +728,53 @@ static unsigned long long parse_number(const char *str) static void parse_pid(const char *str) { + FILE *file; + char buf[5000]; + opt_pid = parse_number(str); -} -static void parse_file(const char *name) -{ + 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 add_addr_range(unsigned long offset, unsigned long size) +static void parse_file(const char *name) { - if (nr_addr_ranges >= MAX_ADDR_RANGES) - fatal("too much addr ranges\n"); - - opt_offset[nr_addr_ranges] = offset; - opt_size[nr_addr_ranges] = size; - nr_addr_ranges++; } static void parse_addr_range(const char *optarg) @@ -630,6 +894,8 @@ static struct option opts[] = { { "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 } }; @@ -641,7 +907,7 @@ int main(int argc, char *argv[]) page_size = getpagesize(); while ((c = getopt_long(argc, argv, - "rp:f:a:b:lLNh", opts, NULL)) != -1) { + "rp:f:a:b:lLNXxh", opts, NULL)) != -1) { switch (c) { case 'r': opt_raw = 1; @@ -667,6 +933,14 @@ int main(int argc, char *argv[]) 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); @@ -676,15 +950,17 @@ int main(int argc, char *argv[]) } } + if (opt_list && opt_pid) + printf("voffset\t"); if (opt_list == 1) - printf("offset\tcount\tflags\n"); + printf("offset\tlen\tflags\n"); if (opt_list == 2) printf("offset\tflags\n"); walk_addr_ranges(); if (opt_list == 1) - show_page_range(0, 0); /* drain the buffer */ + show_page_range(0, 0, 0); /* drain the buffer */ if (opt_no_summary) return 0; |