Trivial patch:
./btrfs-progs/btrfs-select-super -s 0 /dev/sdc
using SB copy 0, bytenr 65536
No valid Btrfs found on /dev/sdc
Open ctree failed
The line 'using..' is confusing which gives an
indication that command is successful
This patch will avoid that when command fails
Signed-off-by: Anand Jain <anand.jain@oracle.com>
check_mounted() returns kernel-style negative errors.
Patch drops sign for strerror().
Before the patch:
check_mounted(): Could not open /dev/sdb2
Could not check mount status: Unknown error 18446744073709551603
After the patch:
check_mounted(): Could not open /dev/sdb2
Could not check mount status: Permission denied
Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
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>