[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_qdio.c b/drivers/s390/scsi/zfcp_qdio.c
index fb218dd..24e16ec 100644
--- a/drivers/s390/scsi/zfcp_qdio.c
+++ b/drivers/s390/scsi/zfcp_qdio.c
@@ -446,37 +446,37 @@
zfcp_qdio_reqid_check(struct zfcp_adapter *adapter, void *sbale_addr)
{
struct zfcp_fsf_req *fsf_req;
- int retval = 0;
/* invalid (per convention used in this driver) */
if (unlikely(!sbale_addr)) {
ZFCP_LOG_NORMAL("bug: invalid reqid\n");
- retval = -EINVAL;
- goto out;
+ return -EINVAL;
}
/* valid request id and thus (hopefully :) valid fsf_req address */
fsf_req = (struct zfcp_fsf_req *) sbale_addr;
+ /* serialize with zfcp_fsf_req_dismiss_all */
+ spin_lock(&adapter->fsf_req_list_lock);
+ if (list_empty(&adapter->fsf_req_list_head)) {
+ spin_unlock(&adapter->fsf_req_list_lock);
+ return 0;
+ }
+ list_del(&fsf_req->list);
+ atomic_dec(&adapter->fsf_reqs_active);
+ spin_unlock(&adapter->fsf_req_list_lock);
+
if (unlikely(adapter != fsf_req->adapter)) {
ZFCP_LOG_NORMAL("bug: invalid reqid (fsf_req=%p, "
"fsf_req->adapter=%p, adapter=%p)\n",
fsf_req, fsf_req->adapter, adapter);
- retval = -EINVAL;
- goto out;
- }
-
- ZFCP_LOG_TRACE("fsf_req at %p, QTCB at %p\n", fsf_req, fsf_req->qtcb);
- if (likely(fsf_req->qtcb)) {
- ZFCP_LOG_TRACE("hex dump of QTCB:\n");
- ZFCP_HEX_DUMP(ZFCP_LOG_LEVEL_TRACE, (char *) fsf_req->qtcb,
- sizeof(struct fsf_qtcb));
+ return -EINVAL;
}
/* finish the FSF request */
zfcp_fsf_req_complete(fsf_req);
- out:
- return retval;
+
+ return 0;
}
/**