The current user might not be able to peek into the loop files directly,
use the helper. Discovered by running tests in travis.
Signed-off-by: David Sterba <dsterba@suse.com>
We use a device mapper device on top of a loop device, the change in
rotational status does not always propagate if change it at the loop
device sysfs node.
Signed-off-by: David Sterba <dsterba@suse.com>
A test for "btrfs-progs: mkfs: increase buffer size in is_ssd". Create a
device with a long name through loop device wrapped to a device mapper
linear device, switch it to the "ssd" mode status.
Signed-off-by: David Sterba <dsterba@suse.com>
