cluster/dht : Ftruncate on migrating file fails with EINVAL

What:
If dht_open is called on a migrating file after the inode_ctx is set,
subsequent FOPs on that fd do not open the fd on the dst subvol.
This is seen when the open-ftruncate-close sequence is repeatedly
called on a migrating file.
A second call to the sequence described above causes dht_truncate_cbk
to call dht_truncate2 as the dht_inode_ctx was already set by the first
call. As dht_rebalance_in_progress_check is not called, the fd is not
opened on the dst subvol.
On a distributed-replicate volume, this causes AFR to
open the fd using afr_fix_open, but with the wrong flags, causing
posix_ftruncate to fail with EINVAL.
The fix: We require fd specific information to make a decision while
handling migrating files.
Set the fd_ctx to indicate the fd has been opened on the dst subvol
and check if it has been set while processing Phase1/Phase2 checks
in the FOP callback functions.

Change-Id: I43cdcd8017b4a11e18afdd210469de7cd9a5ef14
BUG: 1284823
Signed-off-by: N Balachandran <nbalacha@redhat.com>
Reviewed-on: http://review.gluster.org/12985
Reviewed-by: Raghavendra G <rgowdapp@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Dan Lambright <dlambrig@redhat.com>
Tested-by: Dan Lambright <dlambrig@redhat.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/xlators/cluster/dht/src/dht-mem-types.h b/xlators/cluster/dht/src/dht-mem-types.h
index a90b5710745..27ebf9dc501 100644
--- a/xlators/cluster/dht/src/dht-mem-types.h
+++ b/xlators/cluster/dht/src/dht-mem-types.h
@@ -36,6 +36,7 @@ enum gf_dht_mem_types_ {
         gf_dht_mt_miginfo_t,
         gf_tier_mt_bricklist_t,
         gf_tier_mt_ipc_ctr_params_t,
+        gf_dht_mt_fd_ctx_t,
         gf_dht_mt_end
 };
 #endif