gfapi: Skip and delete the upcall entry if not found

We could run into situations where in gfapi received a upcall
notification for a file and the file may have got deleted by then.
Hence, incase of error while trying to create handle from gfid,
log it, delete the entry and return with CBK_NULL reason.

Change-Id: I191f10f44d6804be07734a6be63a3ca08f455f0e
BUG: 1218566
Signed-off-by: Soumya Koduri <skoduri@redhat.com>
Reviewed-on: http://review.gluster.org/10341
Reviewed-by: Kaleb KEITHLEY <kkeithle@redhat.com>
Reviewed-on: http://review.gluster.org/10565
Tested-by: NetBSD Build System

1 files changed, 32 insertions, 20 deletions

diff --git a/api/src/glfs-handleops.c b/api/src/glfs-handleops.c
index e22b541b4ac..b02aefc7477 100644
--- a/api/src/glfs-handleops.c
+++ b/api/src/glfs-handleops.c
@@ -1756,26 +1756,38 @@ pub_glfs_h_poll_upcall (struct glfs *fs, struct callback_arg *up_arg)
                                                     NULL);
 
                 if (!object) {
-                        errno = ENOMEM;
-                        goto out;
-                }
-
-                upcall_data = &u_list->upcall_data;
-
-                switch (upcall_data->event_type) {
-                case GF_UPCALL_CACHE_INVALIDATION:
-                        /* XXX: Need to revisit this to support
-                         * GFAPI_INODE_UPDATE if required.
-                         */
-                        ca_data = upcall_data->data;
-                        GF_VALIDATE_OR_GOTO ("glfs_h_poll_upcall",
-                                             ca_data, out);
-                        reason = GFAPI_INODE_INVALIDATE;
-                        up_arg->flags = ca_data->flags;
-                        up_arg->expire_time_attr = ca_data->expire_time_attr;
-                        break;
-                default:
-                        break;
+                        /* It could so happen that the file which got
+                         * upcall notification may have got deleted
+                         * by other thread. Irrespective of the error,
+                         * log it and return with CBK_NULL reason.
+                         *
+                         * Applications will ignore this notification
+                         * as up_arg->object will be NULL */
+                        gf_log (subvol->name, GF_LOG_WARNING,
+                                "handle creation of %s failed: %s",
+                                uuid_utoa (gfid), strerror (errno));
+
+                        reason = GFAPI_CBK_EVENT_NULL;
+                } else {
+
+                        upcall_data = &u_list->upcall_data;
+
+                        switch (upcall_data->event_type) {
+                        case GF_UPCALL_CACHE_INVALIDATION:
+                                /* XXX: Need to revisit this to support
+                                 * GFAPI_INODE_UPDATE if required.
+                                 */
+                                ca_data = upcall_data->data;
+                                GF_VALIDATE_OR_GOTO ("glfs_h_poll_upcall",
+                                                     ca_data, out);
+                                reason = GFAPI_INODE_INVALIDATE;
+                                up_arg->flags = ca_data->flags;
+                                up_arg->expire_time_attr = ca_data->expire_time_attr;
+
+                                break;
+                        default:
+                                break;
+                        }
                 }
 
                 up_arg->object = object;