File 0124-btrfs-progs-Add-utility-to-dump-all-superblocks-foun.patch of Package btrfsprogs
From db874f1e8924e86bbdee6600b0e5b3e6d11f9238 Mon Sep 17 00:00:00 2001
From: David Marcin <djmarcin@google.com>
Date: Tue, 22 Nov 2011 10:08:00 -0800
Subject: [PATCH 25/35] btrfs-progs: Add utility to dump all superblocks found
on a device.
Signed-off-by: David Marcin <djmarcin@google.com>
---
.gitignore | 4 ++
Makefile | 9 ++++-
btrfs-dump-super.c | 87 ++++++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 98 insertions(+), 2 deletions(-)
create mode 100644 btrfs-dump-super.c
Index: btrfs-progs-v0.19-117-g6da41f2/.gitignore
===================================================================
--- btrfs-progs-v0.19-117-g6da41f2.orig/.gitignore
+++ btrfs-progs-v0.19-117-g6da41f2/.gitignore
@@ -3,12 +3,16 @@
version.h
man/*.gz
btrfs
+btrfs-corrupt-block
btrfs-debug-tree
+btrfs-dump-super
btrfs-map-logical
+btrfs-select-super
btrfs-show
btrfs-vol
btrfsck
btrfsctl
+calc-size
find-root
mkfs.btrfs
repair
Index: btrfs-progs-v0.19-117-g6da41f2/Makefile
===================================================================
--- btrfs-progs-v0.19-117-g6da41f2.orig/Makefile
+++ btrfs-progs-v0.19-117-g6da41f2/Makefile
@@ -17,7 +17,8 @@ LIBS=-luuid
RESTORE_LIBS=-lz
progs = btrfsctl mkfs.btrfs btrfs-debug-tree btrfs-show btrfs-vol btrfsck \
- btrfs btrfs-map-logical restore find-root calc-size btrfs-corrupt-block
+ btrfs btrfs-map-logical restore find-root calc-size btrfs-corrupt-block \
+ btrfs-dump-super
btrfs_man_page_source = btrfs.c btrfs_cmds.c scrub.c
@@ -76,6 +77,9 @@ btrfs-zero-log: $(objects) btrfs-zero-lo
btrfs-select-super: $(objects) btrfs-select-super.o
$(CC) $(CFLAGS) -o btrfs-select-super $(objects) btrfs-select-super.o $(LDFLAGS) $(LIBS)
+btrfs-dump-super: $(objects) btrfs-dump-super.o
+ $(CC) $(CFLAGS) -o btrfs-dump-super $(objects) btrfs-dump-super.o $(LDFLAGS) $(LIBS)
+
btrfstune: $(objects) btrfstune.o
$(CC) $(CFLAGS) -o btrfstune $(objects) btrfstune.o $(LDFLAGS) $(LIBS)
@@ -128,7 +132,8 @@ install-man:
clean :
rm -f man/btrfs.8.in
rm -f $(progs) cscope.out *.o .*.d btrfs-convert btrfs-image btrfs-select-super \
- btrfs-zero-log btrfstune dir-test ioctl-test quick-test version.h
+ btrfs-dump-super btrfs-zero-log btrfstune dir-test ioctl-test quick-test \
+ version.h
rm -f helpmsg.c
cd man; make clean
Index: btrfs-progs-v0.19-117-g6da41f2/btrfs-dump-super.c
===================================================================
--- /dev/null
+++ btrfs-progs-v0.19-117-g6da41f2/btrfs-dump-super.c
@@ -0,0 +1,87 @@
+/*
+ * Copyright (C) 2011 Google. 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 "version.h"
+
+static void print_usage(void)
+{
+ fprintf(stderr, "usage: btrfs-dump-super dev\n");
+ fprintf(stderr, "%s\n", BTRFS_BUILD_VERSION);
+ exit(1);
+}
+
+static int read_block(const char* filename, u64 bytenr, struct btrfs_super_block* sb) {
+ int fd = open(filename, O_RDONLY, 0600);
+ int block_size = sizeof(struct btrfs_super_block);
+ int bytes_read = 0;
+
+ if (fd < 0) {
+ fprintf(stderr, "Could not open %s\n", filename);
+ return -1;
+ }
+
+ bytes_read = pread(fd, sb, block_size, bytenr);
+ if (bytes_read < block_size) {
+ fprintf(stderr, "Only read %d bytes of %d.\n", bytes_read, block_size);
+ }
+
+ close(fd);
+ return bytes_read;
+}
+
+int main(int ac, char **av)
+{
+ int i;
+
+ if (ac != 2)
+ print_usage();
+
+ for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
+ u64 bytenr = btrfs_sb_offset(i);
+ int fd;
+ struct btrfs_super_block sb;
+ int block_size = sizeof(struct btrfs_super_block);
+ char filename[1024];
+ int bytes_read = read_block(av[optind], bytenr, &sb);
+ if (bytes_read < block_size)
+ continue;
+
+ sprintf(filename, "/tmp/block.%s.%llu",
+ strrchr(av[optind], '/') + 1, bytenr);
+ fd = open(filename, O_CREAT|O_WRONLY, 0644);
+ if (block_size != pwrite(fd, &sb, block_size, 0)) {
+ fprintf(stderr, "Failed to dump superblock %d", i);
+ continue;
+ }
+ fprintf(stderr, "Dumped superblock %s:%d, gen %llu to %s.\n",
+ av[optind], i, sb.generation, filename);
+ close(fd);
+ }
+
+ return 0;
+}
