cluster/afr: Preserve errno in case of failures on all subvols

        Backport of http://review.gluster.org/8984

Problem:
When quorum is enabled and the fop fails on all the subvolumes,
op_errno is set to EROFS which overrides the actual errno returned
from bricks.

Fix:
Don't override the errno when fop fails on all subvols.

Change-Id: I61e57bbf1a69407230ec172a983de18d1c624fd2
BUG: 1162122
Signed-off-by: Pranith Kumar K <pkarampu@redhat.com>
Reviewed-on: http://review.gluster.org/9087
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

1 files changed, 16 insertions, 5 deletions

diff --git a/xlators/cluster/afr/src/afr-transaction.c b/xlators/cluster/afr/src/afr-transaction.c
index d287e6ab66c..bb582b5940f 100644
--- a/xlators/cluster/afr/src/afr-transaction.c
+++ b/xlators/cluster/afr/src/afr-transaction.c
@@ -507,6 +507,10 @@ afr_handle_quorum (call_frame_t *frame)
         if (priv->quorum_count == 0)
                 return;
 
+        /* If the fop already failed return right away to preserve errno */
+        if (local->op_ret == -1)
+                return;
+
         /*
          * Network split may happen just after the fops are unwound, so check
          * if the fop succeeded in a way it still follows quorum. If it doesn't,
@@ -975,16 +979,23 @@ afr_changelog_pre_op (call_frame_t *frame, xlator_t *this)
 		}
 	}
 
-        if (priv->quorum_count && !afr_has_fop_quorum (frame)) {
-                op_errno = EROFS;
-                goto err;
-        }
-
+        /* This condition should not be met with present code, as
+         * transaction.done will be called if locks are not acquired on even a
+         * single node.
+         */
         if (call_count == 0) {
 		op_errno = ENOTCONN;
 		goto err;
 	}
 
+        /* Check if the fop can be performed on at least
+         * quorum number of nodes.
+         */
+        if (priv->quorum_count && !afr_has_fop_quorum (frame)) {
+                op_errno = EROFS;
+                goto err;
+        }
+
 	xdata_req = dict_new();
 	if (!xdata_req) {
 		op_errno = ENOMEM;