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>

1 files changed, 1 insertions, 1 deletions

diff --git a/disk-io.c b/disk-io.c
index fef3edab..f4368f3d 100644
--- a/disk-io.c
+++ b/disk-io.c
@@ -829,7 +829,7 @@ 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);