[SCSI] zfcp: fix bug during adapter shutdown
Fixes a race between zfcp_fsf_req_dismiss_all and
zfcp_qdio_reqid_check. During adapter shutdown it occurred that a
request was cleaned up twice. First during its normal
completion. Second when dismiss_all was called. The fix is to
serialize access to fsf request list between zfcp_fsf_req_dismiss_all
and zfcp_qdio_reqid_check and delete a fsf request from the list if
its completion is triggered. (Additionally a rwlock was replaced by a
spinlock and fsf_req_cleanup was eliminated.)
Signed-off-by: Andreas Herrmann <aherrman@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/drivers/s390/scsi/zfcp_erp.c b/drivers/s390/scsi/zfcp_erp.c
index 41c67e1..6d73891 100644
--- a/drivers/s390/scsi/zfcp_erp.c
+++ b/drivers/s390/scsi/zfcp_erp.c
@@ -891,7 +891,7 @@
if (erp_action->fsf_req) {
/* take lock to ensure that request is not being deleted meanwhile */
- write_lock(&adapter->fsf_req_list_lock);
+ spin_lock(&adapter->fsf_req_list_lock);
/* check whether fsf req does still exist */
list_for_each_entry(fsf_req, &adapter->fsf_req_list_head, list)
if (fsf_req == erp_action->fsf_req)
@@ -934,7 +934,7 @@
*/
erp_action->fsf_req = NULL;
}
- write_unlock(&adapter->fsf_req_list_lock);
+ spin_unlock(&adapter->fsf_req_list_lock);
} else
debug_text_event(adapter->erp_dbf, 3, "a_ca_noreq");