target: Propigate up ->cmd_kref put return via transport_generic_free_cmd

Go ahead and propigate up the ->cmd_kref put return value from
target_put_sess_cmd() -> transport_release_cmd() -> transport_put_cmd()
-> transport_generic_free_cmd().

This is useful for certain fabrics when determining the active I/O
shutdown case with SCF_ACK_KREF where a final target_put_sess_cmd()
is still required by the caller.

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

2 files changed, 16 insertions, 14 deletions

diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index bbca144821c5..21e315874a54 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -65,7 +65,7 @@ static void transport_complete_task_attr(struct se_cmd *cmd);
 static void transport_handle_queue_full(struct se_cmd *cmd,
                 struct se_device *dev);
 static int transport_generic_get_mem(struct se_cmd *cmd);
-static void transport_put_cmd(struct se_cmd *cmd);
+static int transport_put_cmd(struct se_cmd *cmd);
 static void target_complete_ok_work(struct work_struct *work);
 
 int init_se_kmem_caches(void)
@@ -1944,7 +1944,7 @@ static inline void transport_free_pages(struct se_cmd *cmd)
  * This routine unconditionally frees a command, and reference counting
  * or list removal must be done in the caller.
  */
-static void transport_release_cmd(struct se_cmd *cmd)
+static int transport_release_cmd(struct se_cmd *cmd)
 {
         BUG_ON(!cmd->se_tfo);
 
@@ -1956,11 +1956,11 @@ static void transport_release_cmd(struct se_cmd *cmd)
          * If this cmd has been setup with target_get_sess_cmd(), drop
          * the kref and call ->release_cmd() in kref callback.
          */
-         if (cmd->check_release != 0) {
-                target_put_sess_cmd(cmd->se_sess, cmd);
-                return;
-        }
+         if (cmd->check_release != 0)
+                return target_put_sess_cmd(cmd->se_sess, cmd);
+
         cmd->se_tfo->release_cmd(cmd);
+        return 1;
 }
 
 /**
@@ -1969,7 +1969,7 @@ static void transport_release_cmd(struct se_cmd *cmd)
  *
  * This routine releases our reference to the command and frees it if possible.
  */
-static void transport_put_cmd(struct se_cmd *cmd)
+static int transport_put_cmd(struct se_cmd *cmd)
 {
         unsigned long flags;
 
@@ -1977,7 +1977,7 @@ static void transport_put_cmd(struct se_cmd *cmd)
         if (atomic_read(&cmd->t_fe_count) &&
             !atomic_dec_and_test(&cmd->t_fe_count)) {
                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-                return;
+                return 0;
         }
 
         if (cmd->transport_state & CMD_T_DEV_ACTIVE) {
@@ -1987,8 +1987,7 @@ static void transport_put_cmd(struct se_cmd *cmd)
         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 
         transport_free_pages(cmd);
-        transport_release_cmd(cmd);
-        return;
+        return transport_release_cmd(cmd);
 }
 
 void *transport_kmap_data_sg(struct se_cmd *cmd)
@@ -2153,13 +2152,15 @@ static void transport_write_pending_qf(struct se_cmd *cmd)
         }
 }
 
-void transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
+int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
 {
+        int ret = 0;
+
         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
                 if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
                          transport_wait_for_tasks(cmd);
 
-                transport_release_cmd(cmd);
+                ret = transport_release_cmd(cmd);
         } else {
                 if (wait_for_tasks)
                         transport_wait_for_tasks(cmd);
@@ -2167,8 +2168,9 @@ void transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
                 if (cmd->se_lun)
                         transport_lun_remove_cmd(cmd);
 
-                transport_put_cmd(cmd);
+                ret = transport_put_cmd(cmd);
         }
+        return ret;
 }
 EXPORT_SYMBOL(transport_generic_free_cmd);
 
diff --git a/include/target/target_core_fabric.h b/include/target/target_core_fabric.h
index 8a26f0d55fd1..1dcce9cc99b9 100644
--- a/include/target/target_core_fabric.h
+++ b/include/target/target_core_fabric.h
@@ -114,7 +114,7 @@ sense_reason_t	transport_generic_new_cmd(struct se_cmd *);
 
 void    target_execute_cmd(struct se_cmd *cmd);
 
-void    transport_generic_free_cmd(struct se_cmd *, int);
+int     transport_generic_free_cmd(struct se_cmd *, int);
 
 bool    transport_wait_for_tasks(struct se_cmd *);
 int     transport_check_aborted_status(struct se_cmd *, int);