afr: fix bug-1363721.t failure

Problem:
In the .t, when the only good brick was brought down, writes on the fd were
still succeeding on the bad bricks. The inflight split-brain check was
marking the write as failure but since the write succeeded on all the
bad bricks, afr_txn_nothing_failed() was set to true and we were
unwinding writev with success to DHT and then catching the failure in
post-op in the background.

Fix:
Don't wind the FOP phase if the write_subvol (which is populated with readable
subvols obtained in pre-op cbk) does not have at least 1 good brick which was up
when the transaction started.

Note: This fix is not related to brick muliplexing. I ran the .t
10 times with this fix and brick-mux enabled without any failures.

Change-Id: I915c9c366aa32cd342b1565827ca2d83cb02ae85
updates: bz#1577672
Signed-off-by: Ravishankar N <ravishankar@redhat.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/xlators/cluster/afr/src/afr-common.c b/xlators/cluster/afr/src/afr-common.c
index c313294961f..ad037cd7060 100644
--- a/xlators/cluster/afr/src/afr-common.c
+++ b/xlators/cluster/afr/src/afr-common.c
@@ -6631,6 +6631,20 @@ out:
         return ret;
 }
 
+uint64_t
+afr_write_subvol_get (call_frame_t *frame, xlator_t *this)
+{
+        afr_local_t *local = NULL;
+        uint64_t write_subvol = 0;
+
+        local = frame->local;
+        LOCK(&local->inode->lock);
+                write_subvol = local->inode_ctx->write_subvol;
+        UNLOCK (&local->inode->lock);
+
+        return write_subvol;
+}
+
 int
 afr_write_subvol_set (call_frame_t *frame, xlator_t *this)
 {