[SCSI] zfcp: Block FC transport rports early on errors
Use the I/O blocking mechanism in the FC transport class to allow
faster failovers for multipathing:
- Call fc_remote_port_delete early to set the rport to BLOCKED.
- Check the rport status in queuecommand with fc_remote_portchkready
to no longer accept new I/O for this port and fail the I/O with the
appropriate scsi_cmnd result.
- Implement the terminate_rport_io handler to abort all pending I/O
requests
- Return SCSI commands with DID_TRANSPORT_DISRUPTED while erp is
running.
- When updating the remote port status, check for late changes and
update the remote ports status accordingly.
Acked-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/s390/scsi/zfcp_fc.c b/drivers/s390/scsi/zfcp_fc.c
index 49a7a90..c22c478 100644
--- a/drivers/s390/scsi/zfcp_fc.c
+++ b/drivers/s390/scsi/zfcp_fc.c
@@ -3,7 +3,7 @@
*
* Fibre Channel related functions for the zfcp device driver.
*
- * Copyright IBM Corporation 2008
+ * Copyright IBM Corporation 2008, 2009
*/
#define KMSG_COMPONENT "zfcp"
@@ -376,10 +376,14 @@
port->wwnn = ls_adisc->wwnn;
if ((port->wwpn != ls_adisc->wwpn) ||
- !(atomic_read(&port->status) & ZFCP_STATUS_COMMON_OPEN))
+ !(atomic_read(&port->status) & ZFCP_STATUS_COMMON_OPEN)) {
zfcp_erp_port_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED,
"fcadh_2", NULL);
+ goto out;
+ }
+ /* port is good, unblock rport without going through erp */
+ zfcp_scsi_schedule_rport_register(port);
out:
zfcp_port_put(port);
kfree(adisc);
@@ -423,14 +427,23 @@
container_of(work, struct zfcp_port, test_link_work);
int retval;
+ if (!(atomic_read(&port->status) & ZFCP_STATUS_COMMON_UNBLOCKED)) {
+ zfcp_port_put(port);
+ return; /* port erp is running and will update rport status */
+ }
+
+ zfcp_port_get(port);
+ port->rport_task = RPORT_DEL;
+ zfcp_scsi_rport_work(&port->rport_work);
+
retval = zfcp_fc_adisc(port);
if (retval == 0)
return;
/* send of ADISC was not possible */
+ zfcp_erp_port_forced_reopen(port, 0, "fcltwk1", NULL);
+
zfcp_port_put(port);
- if (retval != -EBUSY)
- zfcp_erp_port_forced_reopen(port, 0, "fcltwk1", NULL);
}
/**