[PATCH 0/2] btrfs-progs: read device fsid from the sysfs

[Anand Jain <anand.jain@oracle.com>]

The following test case fails as it trying to read the fsid from the sb
for a missing device.

   $ mkfs.btrfs -f -draid1 -mraid1 $DEV1 $DEV2 
   $ btrfstune -S 1 $DEV1 
   $ wipefs -a $DEV2 
   $ btrfs dev scan --forget 
   $ mount -o degraded $DEV1 /btrfs 
   $ btrfs device add $DEV3 /btrfs -f 

   $ btrfs fi us /btrfs 
     ERROR: unexpected number of devices: 1 >= 1 
     ERROR: if seed device is used, try running this command as root
 
The kernel patch [1] in the mailing list provided a sysfs interface
to read the fsid of the device, so use it instead.

 [1]  btrfs: sysfs add devinfo/fsid to retrieve fsid from the device

This patch also retains the old method that is to read the SB for
backward compatibility purposes.

Anand Jain (2):
  btrfs-progs: prepare helper device_is_seed
  btrfs-progs: read fsid from the sysfs in device_is_seed

 cmds/filesystem-usage.c | 47 ++++++++++++++++++++++++++++++++++++-----
 1 file changed, 42 insertions(+), 5 deletions(-)

-- 
2.31.1