1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
|
Upstream-Status: Inappropriate [Backport]
From 70c6c10134b502fa69955746554031939b85fb0c Mon Sep 17 00:00:00 2001
From: Chris Mason <chris.mason@oracle.com>
Date: Thu, 9 Dec 2010 16:36:29 -0500
Subject: [PATCH 01/15] Btrfs-progs: add a btrfs-select-super command to overwrite the super
Btrfs stores multiple copies of the superblock, and for common power-failure
crashes where barriers were not in use, one of the super copies is often
valid while the first copy is not.
This adds a btrfs-select-super -s N /dev/xxx command, which can
overwrite all the super blocks with a copy that you have already
determined is valid with btrfsck -s
Signed-off-by: Chris Mason <chris.mason@oracle.com>
---
Makefile | 3 ++
btrfs-select-super.c | 99 ++++++++++++++++++++++++++++++++++++++++++++++++++
disk-io.c | 2 +-
disk-io.h | 1 +
4 files changed, 104 insertions(+), 1 deletions(-)
create mode 100644 btrfs-select-super.c
diff --git a/Makefile b/Makefile
index 6e6f6c6..d65f6a2 100644
--- a/Makefile
+++ b/Makefile
@@ -62,6 +62,9 @@ btrfs-debug-tree: $(objects) debug-tree.o
btrfs-zero-log: $(objects) btrfs-zero-log.o
gcc $(CFLAGS) -o btrfs-zero-log $(objects) btrfs-zero-log.o $(LDFLAGS) $(LIBS)
+btrfs-select-super: $(objects) btrfs-select-super.o
+ gcc $(CFLAGS) -o btrfs-select-super $(objects) btrfs-select-super.o $(LDFLAGS) $(LIBS)
+
btrfstune: $(objects) btrfstune.o
gcc $(CFLAGS) -o btrfstune $(objects) btrfstune.o $(LDFLAGS) $(LIBS)
diff --git a/btrfs-select-super.c b/btrfs-select-super.c
new file mode 100644
index 0000000..f12f36c
--- /dev/null
+++ b/btrfs-select-super.c
@@ -0,0 +1,99 @@
+/*
+ * Copyright (C) 2007 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 <unistd.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include "kerncompat.h"
+#include "ctree.h"
+#include "disk-io.h"
+#include "print-tree.h"
+#include "transaction.h"
+#include "list.h"
+#include "version.h"
+#include "utils.h"
+
+static void print_usage(void)
+{
+ fprintf(stderr, "usage: btrfs-select-super -s number dev\n");
+ fprintf(stderr, "%s\n", BTRFS_BUILD_VERSION);
+ exit(1);
+}
+
+int main(int ac, char **av)
+{
+ struct btrfs_root *root;
+ int ret;
+ int num;
+ u64 bytenr = 0;
+
+ while(1) {
+ int c;
+ c = getopt(ac, av, "s:");
+ if (c < 0)
+ break;
+ switch(c) {
+ case 's':
+ num = atol(optarg);
+ bytenr = btrfs_sb_offset(num);
+ printf("using SB copy %d, bytenr %llu\n", num,
+ (unsigned long long)bytenr);
+ break;
+ default:
+ print_usage();
+ }
+ }
+ ac = ac - optind;
+
+ if (ac != 1)
+ print_usage();
+
+ if (bytenr == 0) {
+ fprintf(stderr, "Please select the super copy with -s\n");
+ print_usage();
+ }
+
+ radix_tree_init();
+
+ if((ret = check_mounted(av[optind])) < 0) {
+ fprintf(stderr, "Could not check mount status: %s\n", strerror(ret));
+ return ret;
+ } else if(ret) {
+ fprintf(stderr, "%s is currently mounted. Aborting.\n", av[optind]);
+ return -EBUSY;
+ }
+
+ root = open_ctree(av[optind], bytenr, 1);
+
+ if (root == NULL)
+ return 1;
+
+ /* make the super writing code think we've read the first super */
+ root->fs_info->super_bytenr = BTRFS_SUPER_INFO_OFFSET;
+ ret = write_all_supers(root);
+
+ /* we don't close the ctree or anything, because we don't want a real
+ * transaction commit. We just want the super copy we pulled off the
+ * disk to overwrite all the other copies
+ */
+ return ret;
+}
diff --git a/disk-io.c b/disk-io.c
index a6e1000..5bd9cfc 100644
--- a/disk-io.c
+++ b/disk-io.c
@@ -828,7 +828,7 @@ int write_dev_supers(struct btrfs_root *root, struct btrfs_super_block *sb,
if (root->fs_info->super_bytenr != BTRFS_SUPER_INFO_OFFSET) {
btrfs_set_super_bytenr(sb, root->fs_info->super_bytenr);
-
+printk("speiiiiiiiiiiiiiiiiiiiiiiiiiiiii\n");
crc = ~(u32)0;
crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE, crc,
BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
diff --git a/disk-io.h b/disk-io.h
index 49e5692..7ebec24 100644
--- a/disk-io.h
+++ b/disk-io.h
@@ -47,6 +47,7 @@ struct btrfs_root *open_ctree(const char *filename, u64 sb_bytenr, int writes);
struct btrfs_root *open_ctree_fd(int fp, const char *path, u64 sb_bytenr,
int writes);
int close_ctree(struct btrfs_root *root);
+int write_all_supers(struct btrfs_root *root);
int write_ctree_super(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr);
--
1.7.2.3
|
