dht: lock on subvols to prevent lookup vs rmdir race

There is a possibility that while an rmdir is completed on
some non-hashed subvol and proceeding to others, a lookup
selfheal can recreate the same directory on those subvols
for which the rmdir had succeeded. Now the deletion of the
parent directory will fail with an ENOTEMPTY.

To fix this take blocking inodelk on the subvols before
starting rmdir. Selfheal must also take blocking inodelk
before creating the entry.

Backport of http://review.gluster.org/13528

> Change-Id: I168a195c35ac1230ba7124d3b0ca157755b3df96
> BUG: 1245065
> Signed-off-by: Sakshi <sabansal@redhat.com>
> Reviewed-on: http://review.gluster.org/13528
> CentOS-regression: Gluster Build System <jenkins@build.gluster.com>
> NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
> Smoke: Gluster Build System <jenkins@build.gluster.com>
> Reviewed-by: Raghavendra G <rgowdapp@redhat.com>
> Tested-by: Raghavendra G <rgowdapp@redhat.com>

Change-Id: I168a195c35ac1230ba7124d3b0ca157755b3df96
BUG: 1257894
Signed-off-by: Sakshi <sabansal@redhat.com>
Reviewed-on: http://review.gluster.org/13915
Smoke: Gluster Build System <jenkins@build.gluster.com>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
Reviewed-by: Raghavendra G <rgowdapp@redhat.com>
CentOS-regression: Gluster Build System <jenkins@build.gluster.com>

0 files changed, 0 insertions, 0 deletions