staging/lustre/ptlrpc: fix import state during replay

Client doesn't restore import state correctly
on reconnect during replay. It resends lock replay
when final ping was queued by server.
Server fails with "target_queue_recovery_request())
ASSERTION( req->rq_export->exp_lock_replay_needed ) failed"

Add imp_replay_state to store last replay state.
imp_state is restored from imp_replay_state
during reconnect.
Signed-off-by: Andriy Skulysh <Andriy_Skulysh@xyratex.com>
Signed-off-by: Bob Glossman <bob.glossman@intel.com>
Xyratex-bug-id: MRP-2022
Reviewed-on: http://review.whamcloud.com/12163
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-5651Reviewed-by: Jian Yu <jian.yu@intel.com>
Reviewed-by: James Simmons <uja.ornl@gmail.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/include/lustre_import.h

@@ -218,6 +218,8 @@ struct obd_import {
 	atomic_t	      imp_timeouts;
 	/** Current import state */
 	enum lustre_imp_state     imp_state;
+	/** Last replay state */
+	enum lustre_imp_state	  imp_replay_state;
 	/** History of import states */
 	struct import_state_hist  imp_state_hist[IMP_STATE_HIST_LEN];
 	int		       imp_state_hist_idx;

drivers/staging/lustre/lustre/ptlrpc/import.c

@@ -63,6 +63,19 @@ struct ptlrpc_connect_async_args {
 static void __import_set_state(struct obd_import *imp,
 			       enum lustre_imp_state state)
 {
+	switch (state) {
+	case LUSTRE_IMP_CLOSED:
+	case LUSTRE_IMP_NEW:
+	case LUSTRE_IMP_DISCON:
+	case LUSTRE_IMP_CONNECTING:
+		break;
+	case LUSTRE_IMP_REPLAY_WAIT:
+		imp->imp_replay_state = LUSTRE_IMP_REPLAY_LOCKS;
+		break;
+	default:
+		imp->imp_replay_state = LUSTRE_IMP_REPLAY;
+	}
+
 	imp->imp_state = state;
 	imp->imp_state_hist[imp->imp_state_hist_idx].ish_state = state;
 	imp->imp_state_hist[imp->imp_state_hist_idx].ish_time =
@@ -966,7 +979,7 @@ static int ptlrpc_connect_interpret(const struct lu_env *env,
 			imp->imp_resend_replay = 1;
 			spin_unlock(&imp->imp_lock);
 
-			IMPORT_SET_STATE(imp, LUSTRE_IMP_REPLAY);
+			IMPORT_SET_STATE(imp, imp->imp_replay_state);
 		} else {
 			IMPORT_SET_STATE(imp, LUSTRE_IMP_RECOVER);
 		}