scsi: iscsi: Add iscsi_cls_conn refcount helpers

[ Upstream commit b1d19e8c92cfb0ded180ef3376c20e130414e067 ]

There are a couple places where we could free the iscsi_cls_conn while it's
still in use. This adds some helpers to get/put a refcount on the struct
and converts an exiting user. Subsequent commits will then use the helpers
to fix 2 bugs in the eh code.

Link: https://lore.kernel.org/r/20210525181821.7617-11-michael.christie@oracle.com
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index 41023fc4bf2dcbf9bc1e6fcb05d306eca777ba4d..8c65fc268a40726f3bf3a8257463422600f616ff 100644 (file)
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -1348,7 +1348,6 @@ void iscsi_session_failure(struct iscsi_session *session,
                           enum iscsi_err err)
 {
        struct iscsi_conn *conn;
-       struct device *dev;
 
        spin_lock_bh(&session->frwd_lock);
        conn = session->leadconn;
@@ -1357,10 +1356,8 @@ void iscsi_session_failure(struct iscsi_session *session,
                return;
        }
 
-       dev = get_device(&conn->cls_conn->dev);
+       iscsi_get_conn(conn->cls_conn);
        spin_unlock_bh(&session->frwd_lock);
-       if (!dev)
-               return;
        /*
         * if the host is being removed bypass the connection
         * recovery initialization because we are going to kill
@@ -1370,7 +1367,7 @@ void iscsi_session_failure(struct iscsi_session *session,
                iscsi_conn_error_event(conn->cls_conn, err);
        else
                iscsi_conn_failure(conn, err);
-       put_device(dev);
+       iscsi_put_conn(conn->cls_conn);
 }
 EXPORT_SYMBOL_GPL(iscsi_session_failure);
 

diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index 2735178f15c739c1c54c930c244123dc259f1378..2171dab3e5dc87f0c859dde9c09fccbd7ebb05fb 100644 (file)
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -2353,6 +2353,18 @@ int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
 }
 EXPORT_SYMBOL_GPL(iscsi_destroy_conn);
 
+void iscsi_put_conn(struct iscsi_cls_conn *conn)
+{
+       put_device(&conn->dev);
+}
+EXPORT_SYMBOL_GPL(iscsi_put_conn);
+
+void iscsi_get_conn(struct iscsi_cls_conn *conn)
+{
+       get_device(&conn->dev);
+}
+EXPORT_SYMBOL_GPL(iscsi_get_conn);
+
 /*
  * iscsi interface functions
  */

diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h
index fc5a39839b4b02cc32642379f5eeeee662020af9..f28bb20d627134b7d072562cd4f816c824eabac7 100644 (file)
--- a/include/scsi/scsi_transport_iscsi.h
+++ b/include/scsi/scsi_transport_iscsi.h
@@ -434,6 +434,8 @@ extern void iscsi_remove_session(struct iscsi_cls_session *session);
 extern void iscsi_free_session(struct iscsi_cls_session *session);
 extern struct iscsi_cls_conn *iscsi_create_conn(struct iscsi_cls_session *sess,
                                                int dd_size, uint32_t cid);
+extern void iscsi_put_conn(struct iscsi_cls_conn *conn);
+extern void iscsi_get_conn(struct iscsi_cls_conn *conn);
 extern int iscsi_destroy_conn(struct iscsi_cls_conn *conn);
 extern void iscsi_unblock_session(struct iscsi_cls_session *session);
 extern void iscsi_block_session(struct iscsi_cls_session *session);