2 * Copyright (C) 2009 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
19 #define _XOPEN_SOURCE 500
26 #include "kerncompat.h"
30 #include "print-tree.h"
31 #include "transaction.h"
36 /* we write the mirror info to stdout unless they are dumping the data
39 static FILE *info_file
;
41 static struct extent_buffer
* debug_read_block(struct btrfs_root
*root
,
42 u64 bytenr
, u32 blocksize
, u64 copy
)
45 struct extent_buffer
*eb
;
47 struct btrfs_multi_bio
*multi
= NULL
;
48 struct btrfs_device
*device
;
52 eb
= btrfs_find_create_tree_block(root
, bytenr
, blocksize
);
58 ret
= btrfs_map_block(&root
->fs_info
->mapping_tree
, READ
,
59 eb
->start
, &length
, &multi
,
63 "Error: fails to map mirror%d logical %llu: %s\n",
64 mirror_num
, (unsigned long long)eb
->start
,
66 free_extent_buffer(eb
);
69 device
= multi
->stripes
[0].dev
;
72 eb
->dev_bytenr
= multi
->stripes
[0].physical
;
74 fprintf(info_file
, "mirror %d logical %Lu physical %Lu "
75 "device %s\n", mirror_num
, (unsigned long long)bytenr
,
76 (unsigned long long)eb
->dev_bytenr
, device
->name
);
79 if (!copy
|| mirror_num
== copy
) {
80 ret
= read_extent_from_disk(eb
, 0, eb
->len
);
83 "Error: failed to read extent: mirror %d logical %llu: %s\n",
84 mirror_num
, (unsigned long long)eb
->start
,
86 free_extent_buffer(eb
);
92 num_copies
= btrfs_num_copies(&root
->fs_info
->mapping_tree
,
98 if (mirror_num
> num_copies
)
104 static void print_usage(void) __attribute__((noreturn
));
105 static void print_usage(void)
107 fprintf(stderr
, "usage: btrfs-map-logical [options] device\n");
108 fprintf(stderr
, "\t-l Logical extent to map\n");
109 fprintf(stderr
, "\t-c Copy of the extent to read (usually 1 or 2)\n");
110 fprintf(stderr
, "\t-o Output file to hold the extent\n");
111 fprintf(stderr
, "\t-b Number of bytes to read\n");
115 static struct option long_options
[] = {
116 /* { "byte-count", 1, NULL, 'b' }, */
117 { "logical", 1, NULL
, 'l' },
118 { "copy", 1, NULL
, 'c' },
119 { "output", 1, NULL
, 'o' },
120 { "bytes", 1, NULL
, 'b' },
124 int main(int ac
, char **av
)
126 struct cache_tree root_cache
;
127 struct btrfs_root
*root
;
128 struct extent_buffer
*eb
;
130 char *output_file
= NULL
;
133 int option_index
= 0;
140 c
= getopt_long(ac
, av
, "l:c:o:b:", long_options
,
146 logical
= arg_strtou64(optarg
);
149 copy
= arg_strtou64(optarg
);
152 bytes
= arg_strtou64(optarg
);
155 output_file
= strdup(optarg
);
163 if (check_argc_min(ac
, 1))
171 cache_tree_init(&root_cache
);
173 root
= open_ctree(dev
, 0, 0);
175 fprintf(stderr
, "Open ctree failed\n");
181 if (strcmp(output_file
, "-") == 0) {
185 out_fd
= open(output_file
, O_RDWR
| O_CREAT
, 0600);
188 ret
= ftruncate(out_fd
, 0);
199 bytes
= root
->sectorsize
;
201 bytes
= (bytes
+ root
->sectorsize
- 1) / root
->sectorsize
;
202 bytes
*= root
->sectorsize
;
205 eb
= debug_read_block(root
, logical
, root
->sectorsize
, copy
);
206 if (eb
&& output_file
) {
207 ret
= write(out_fd
, eb
->data
, eb
->len
);
208 if (ret
< 0 || ret
!= eb
->len
) {
210 fprintf(stderr
, "output file write failed\n");
214 free_extent_buffer(eb
);
215 logical
+= root
->sectorsize
;
216 bytes
-= root
->sectorsize
;
220 if (output_file
&& out_fd
!= 1)