[SCSI] libfc: avoid exchanges collision during lport reset

Currently timer delay is large and is using msleep to avoid
avoid exchanges collision across lport reset, so instead
do this by initializing exches pool indexes during
reset also.

Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Tested-by: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

drivers/scsi/libfc/fc_exch.c

@@ -1793,6 +1793,9 @@ restart:
 			goto restart;
 		}
 	}
+	pool->next_index = 0;
+	pool->left = FC_XID_UNKNOWN;
+	pool->right = FC_XID_UNKNOWN;
 	spin_unlock_bh(&pool->lock);
 }
 
@@ -2281,6 +2284,7 @@ struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *lport,
 		goto free_mempool;
 	for_each_possible_cpu(cpu) {
 		pool = per_cpu_ptr(mp->pool, cpu);
+		pool->next_index = 0;
 		pool->left = FC_XID_UNKNOWN;
 		pool->right = FC_XID_UNKNOWN;
 		spin_lock_init(&pool->lock);

drivers/scsi/libfc/fc_lport.c

@@ -1030,16 +1030,8 @@ static void fc_lport_enter_reset(struct fc_lport *lport)
 			   FCH_EVT_LIPRESET, 0);
 	fc_vports_linkchange(lport);
 	fc_lport_reset_locked(lport);
-	if (lport->link_up) {
-		/*
-		 * Wait upto resource allocation time out before
-		 * doing re-login since incomplete FIP exchanged
-		 * from last session may collide with exchanges
-		 * in new session.
-		 */
-		msleep(lport->r_a_tov);
+	if (lport->link_up)
 		fc_lport_enter_flogi(lport);
-	}
 }
 
 /**