scsi: target/core: Make it possible to wait from more than one context for command completion

This patch does not change any functionality but makes the patch that makes
TMF handling synchronous easier to read.

Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Cc: Mike Christie <mchristi@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Disseldorp <ddiss@suse.de>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/target/target_core_transport.c

@@ -1328,7 +1328,8 @@ void transport_init_se_cmd(
 	INIT_LIST_HEAD(&cmd->se_cmd_list);
 	INIT_LIST_HEAD(&cmd->state_list);
 	init_completion(&cmd->t_transport_stop_comp);
-	cmd->compl = NULL;
+	cmd->free_compl = NULL;
+	cmd->abrt_compl = NULL;
 	spin_lock_init(&cmd->t_state_lock);
 	INIT_WORK(&cmd->work, NULL);
 	kref_init(&cmd->cmd_kref);
@@ -2689,7 +2690,7 @@ int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
 			transport_lun_remove_cmd(cmd);
 	}
 	if (aborted)
-		cmd->compl = &compl;
+		cmd->free_compl = &compl;
 	if (!aborted || tas)
 		ret = target_put_sess_cmd(cmd);
 	if (aborted) {
@@ -2756,7 +2757,8 @@ static void target_release_cmd_kref(struct kref *kref)
 {
 	struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
 	struct se_session *se_sess = se_cmd->se_sess;
-	struct completion *compl = se_cmd->compl;
+	struct completion *free_compl = se_cmd->free_compl;
+	struct completion *abrt_compl = se_cmd->abrt_compl;
 	unsigned long flags;
 
 	if (se_sess) {
@@ -2767,8 +2769,10 @@ static void target_release_cmd_kref(struct kref *kref)
 
 	target_free_cmd_mem(se_cmd);
 	se_cmd->se_tfo->release_cmd(se_cmd);
-	if (compl)
-		complete(compl);
+	if (free_compl)
+		complete(free_compl);
+	if (abrt_compl)
+		complete(abrt_compl);
 
 	percpu_ref_put(&se_sess->cmd_count);
 }

include/target/target_core_base.h

@@ -476,7 +476,8 @@ struct se_cmd {
 	struct se_session	*se_sess;
 	struct se_tmr_req	*se_tmr_req;
 	struct list_head	se_cmd_list;
-	struct completion	*compl;
+	struct completion	*free_compl;
+	struct completion	*abrt_compl;
 	const struct target_core_fabric_ops *se_tfo;
 	sense_reason_t		(*execute_cmd)(struct se_cmd *);
 	sense_reason_t (*transport_complete_callback)(struct se_cmd *, bool, int *);