Btrfs-progs: fix wrong arg sb_bytenr for btrfs_scan_fs_devices()

For most time, In open_ctree_*(), we use the first superblock
(BTRFS_SUPER_INFO_OFFSET). However, for btrfs-convert, we don't,
we should pass the correct sb_bytenr to btrfs_scan_fs_devices() rather
than always use BTRFS_SUPER_INFO_OFFSET.This patch fix the following
regression:

mkfs.ext2 <dev>
btrfs-convert <dev>

warning, device 1 is missing
Check tree block failed, want=2670592, have=0
read block failed check_tree_block
Couldn't read chunk root
Segmentation fault (core dumped)

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/disk-io.h b/disk-io.h
index effaa9f..bc749c3 100644
--- a/disk-io.h
+++ b/disk-io.h
@@ -59,7 +59,7 @@ int btrfs_setup_all_roots(struct btrfs_fs_info *fs_info,
 void btrfs_release_all_roots(struct btrfs_fs_info *fs_info);
 void btrfs_cleanup_all_caches(struct btrfs_fs_info *fs_info);
 int btrfs_scan_fs_devices(int fd, const char *path,
-			  struct btrfs_fs_devices **fs_devices);
+			  struct btrfs_fs_devices **fs_devices, u64 sb_bytenr);
 int btrfs_setup_chunk_tree_and_device_map(struct btrfs_fs_info *fs_info);
 
 struct btrfs_root *open_ctree(const char *filename, u64 sb_bytenr, int writes);