blob: 6b475fc69eab11cca3a80328099b9ab49d86bdde [file] [log] [blame]
/*
* Copyright (C) 2009 Oracle. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* 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 have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#define _XOPEN_SOURCE 500
#define _GNU_SOURCE 1
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <getopt.h>
#include "kerncompat.h"
#include "ctree.h"
#include "volumes.h"
#include "disk-io.h"
#include "print-tree.h"
#include "transaction.h"
#include "list.h"
#include "version.h"
#include "utils.h"
/* we write the mirror info to stdout unless they are dumping the data
* to stdout
* */
static FILE *info_file;
static struct extent_buffer * debug_read_block(struct btrfs_root *root,
u64 bytenr, u32 blocksize, u64 copy)
{
int ret;
struct extent_buffer *eb;
u64 length;
struct btrfs_multi_bio *multi = NULL;
struct btrfs_device *device;
int num_copies;
int mirror_num = 1;
eb = btrfs_find_create_tree_block(root, bytenr, blocksize);
if (!eb)
return NULL;
length = blocksize;
while (1) {
ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
eb->start, &length, &multi,
mirror_num, NULL);
if (ret) {
fprintf(info_file,
"Error: fails to map mirror%d logical %llu: %s\n",
mirror_num, (unsigned long long)eb->start,
strerror(-ret));
free_extent_buffer(eb);
return NULL;
}
device = multi->stripes[0].dev;
eb->fd = device->fd;
device->total_ios++;
eb->dev_bytenr = multi->stripes[0].physical;
fprintf(info_file, "mirror %d logical %Lu physical %Lu "
"device %s\n", mirror_num, (unsigned long long)bytenr,
(unsigned long long)eb->dev_bytenr, device->name);
kfree(multi);
if (!copy || mirror_num == copy)
ret = read_extent_from_disk(eb, 0, eb->len);
num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
eb->start, eb->len);
if (num_copies == 1)
break;
mirror_num++;
if (mirror_num > num_copies)
break;
}
return eb;
}
static void print_usage(void) __attribute__((noreturn));
static void print_usage(void)
{
fprintf(stderr, "usage: btrfs-map-logical [options] device\n");
fprintf(stderr, "\t-l Logical extent to map\n");
fprintf(stderr, "\t-c Copy of the extent to read (usually 1 or 2)\n");
fprintf(stderr, "\t-o Output file to hold the extent\n");
fprintf(stderr, "\t-b Number of bytes to read\n");
exit(1);
}
static struct option long_options[] = {
/* { "byte-count", 1, NULL, 'b' }, */
{ "logical", 1, NULL, 'l' },
{ "copy", 1, NULL, 'c' },
{ "output", 1, NULL, 'o' },
{ "bytes", 1, NULL, 'b' },
{ NULL, 0, NULL, 0}
};
int main(int ac, char **av)
{
struct cache_tree root_cache;
struct btrfs_root *root;
struct extent_buffer *eb;
char *dev;
char *output_file = NULL;
u64 logical = 0;
int ret = 0;
int option_index = 0;
u64 copy = 0;
u64 bytes = 0;
int out_fd = 0;
while(1) {
int c;
c = getopt_long(ac, av, "l:c:o:b:", long_options,
&option_index);
if (c < 0)
break;
switch(c) {
case 'l':
logical = arg_strtou64(optarg);
break;
case 'c':
copy = arg_strtou64(optarg);
break;
case 'b':
bytes = arg_strtou64(optarg);
break;
case 'o':
output_file = strdup(optarg);
break;
default:
print_usage();
}
}
set_argv0(av);
ac = ac - optind;
if (check_argc_min(ac, 1))
print_usage();
if (logical == 0)
print_usage();
dev = av[optind];
radix_tree_init();
cache_tree_init(&root_cache);
root = open_ctree(dev, 0, 0);
if (!root) {
fprintf(stderr, "Open ctree failed\n");
exit(1);
}
info_file = stdout;
if (output_file) {
if (strcmp(output_file, "-") == 0) {
out_fd = 1;
info_file = stderr;
} else {
out_fd = open(output_file, O_RDWR | O_CREAT, 0600);
if (out_fd < 0)
goto close;
ret = ftruncate(out_fd, 0);
if (ret) {
ret = 1;
close(out_fd);
goto close;
}
info_file = stdout;
}
}
if (bytes == 0)
bytes = root->sectorsize;
bytes = (bytes + root->sectorsize - 1) / root->sectorsize;
bytes *= root->sectorsize;
while (bytes > 0) {
eb = debug_read_block(root, logical, root->sectorsize, copy);
if (eb && output_file) {
ret = write(out_fd, eb->data, eb->len);
if (ret < 0 || ret != eb->len) {
ret = 1;
fprintf(stderr, "output file write failed\n");
goto out_close_fd;
}
}
free_extent_buffer(eb);
logical += root->sectorsize;
bytes -= root->sectorsize;
}
out_close_fd:
if (output_file && out_fd != 1)
close(out_fd);
close:
close_ctree(root);
return ret;
}