nfs3: Unref & unbind dir fd with inode lock on EOF

..so that when EOF is reached on this fd, any further
requests on the same inode do not get handled through this
fd but result in a new fd being opened.

Unbinding results in the fd getting deleted from the inode's fd list.

Signed-off-by: Shehjar Tikoo <shehjart@gluster.com>
Signed-off-by: Vijay Bellur <vijay@dev.gluster.com>

BUG: 1619 (glusterfs nfs server crashed on dht+replica(2x2))
URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=1619

1 files changed, 12 insertions, 6 deletions

diff --git a/xlators/nfs/server/src/nfs3.c b/xlators/nfs/server/src/nfs3.c
index 0a55e55c9..2d5df5369 100644
--- a/xlators/nfs/server/src/nfs3.c
+++ b/xlators/nfs/server/src/nfs3.c
@@ -3885,6 +3885,17 @@ nfs3svc_readdir_fstat_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
 
         stat = NFS3_OK;
 nfs3err:
+
+        /* On end-of-directory, unref the fd to have it removed from the cache
+         * and also unbind it from the fd so that any subsequent request on the
+         * on the directory do not get this fd when fd_lookup is called in
+         * dir open resume path.
+         */
+        if (is_eof) {
+                gf_log (GF_NFS3, GF_LOG_TRACE, "EOF REF: %d", cs->fd->refcount);
+                fd_unref_unbind (cs->fd);
+        }
+
         if (cs->maxcount == 0) {
                 nfs3_log_readdir_res (nfs_rpcsvc_request_xid (cs->req), stat,
                                       op_errno, (uintptr_t)cs->fd,
@@ -3902,11 +3913,6 @@ nfs3err:
                                      cs->maxcount, is_eof);
         }
 
-        if (is_eof) {
-                gf_log (GF_NFS3, GF_LOG_TRACE, "EOF REF: %d", cs->fd->refcount);
-                fd_unref (cs->fd);
-        }
-
         gf_log (GF_NFS3, GF_LOG_TRACE, "CS WIPE REF: %d", cs->fd->refcount);
         nfs3_call_state_wipe (cs);
         return 0;
@@ -3958,7 +3964,7 @@ err:
          * so that next time the dir is read, we'll get any changed directory
          * entries.
          */
-        fd_unref (cs->fd);
+        fd_unref_unbind (cs->fd);
         nfs3_call_state_wipe (cs);
 ret:
         return 0;