[PATCH 5.10 057/243] scsi: iscsi: Add iscsi_cls_conn refcount helpers

Greg Kroah-Hartman
2021-07-19T17:08:27Z

From: Mike Christie <michael.christie@oracle.com>

[ 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>
---
drivers/scsi/libiscsi.c | 7 ++-----
drivers/scsi/scsi_transport_iscsi.c | 12 ++++++++++++
include/scsi/scsi_transport_iscsi.h | 2 ++
3 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index 41023fc4bf2d..8c65fc268a40 100644
--- 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 2735178f15c7..2171dab3e5dc 100644
--- 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 fc5a39839b4b..f28bb20d6271 100644
--- 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);
--
2.30.2