target: Make target_put_sess_cmd use target_release_cmd_kref
This patch moves target_put_sess_cmd() to use a se_cmd->cmd_kref
callback target_release_cmd_kref when performing driver release of
fabric->se_cmd descriptor memory. It sets the default cmd_kref
count value to '2' within target_get_sess_cmd() setup, and
currently assumes TFO->check_stop_free() usage.
It drops se_tfo->check_release_cmd() usage in the main
transport_release_cmd codepath.
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index 1229256..176f956 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -3349,13 +3349,13 @@
if (cmd->t_task_cdb != cmd->__t_task_cdb)
kfree(cmd->t_task_cdb);
/*
- * Check if target_wait_for_sess_cmds() is expecting to
- * release se_cmd directly here..
+ * 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 && cmd->se_tfo->check_release_cmd)
- if (cmd->se_tfo->check_release_cmd(cmd) != 0)
- return;
-
+ if (cmd->check_release != 0) {
+ target_put_sess_cmd(cmd->se_sess, cmd);
+ return;
+ }
cmd->se_tfo->release_cmd(cmd);
}
@@ -3915,6 +3915,9 @@
{
unsigned long flags;
+ kref_init(&se_cmd->cmd_kref);
+ kref_get(&se_cmd->cmd_kref);
+
spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
se_cmd->check_release = 1;
@@ -3922,30 +3925,36 @@
}
EXPORT_SYMBOL(target_get_sess_cmd);
-/* target_put_sess_cmd - Check for active I/O shutdown or list delete
- * @se_sess: session to reference
- * @se_cmd: command descriptor to drop
- */
-int target_put_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd)
+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;
unsigned long flags;
spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
if (list_empty(&se_cmd->se_cmd_list)) {
spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
WARN_ON(1);
- return 0;
+ return;
}
-
if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
complete(&se_cmd->cmd_wait_comp);
- return 1;
+ return;
}
list_del(&se_cmd->se_cmd_list);
spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
- return 0;
+ se_cmd->se_tfo->release_cmd(se_cmd);
+}
+
+/* target_put_sess_cmd - Check for active I/O shutdown via kref_put
+ * @se_sess: session to reference
+ * @se_cmd: command descriptor to drop
+ */
+int target_put_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd)
+{
+ return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
}
EXPORT_SYMBOL(target_put_sess_cmd);
