[SCSI] zfcp: Replace global config_lock with local list locks
The global config_lock was used to protect the configuration organized
in independent lists. It is not necessary to have a lock on driver
level for this purpose. This patch replaces the global config_lock
with a set of local list locks.
Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
diff --git a/drivers/s390/scsi/zfcp_scsi.c b/drivers/s390/scsi/zfcp_scsi.c
index f546559..6feece3 100644
--- a/drivers/s390/scsi/zfcp_scsi.c
+++ b/drivers/s390/scsi/zfcp_scsi.c
@@ -128,49 +128,44 @@
}
static struct zfcp_unit *zfcp_unit_lookup(struct zfcp_adapter *adapter,
- int channel, unsigned int id,
- unsigned int lun)
+ unsigned int id, u64 lun)
{
+ unsigned long flags;
struct zfcp_port *port;
- struct zfcp_unit *unit;
- int scsi_lun;
+ struct zfcp_unit *unit = NULL;
- list_for_each_entry(port, &adapter->port_list_head, list) {
+ read_lock_irqsave(&adapter->port_list_lock, flags);
+ list_for_each_entry(port, &adapter->port_list, list) {
if (!port->rport || (id != port->rport->scsi_target_id))
continue;
- list_for_each_entry(unit, &port->unit_list_head, list) {
- scsi_lun = scsilun_to_int(
- (struct scsi_lun *)&unit->fcp_lun);
- if (lun == scsi_lun)
- return unit;
- }
+ unit = zfcp_get_unit_by_lun(port, lun);
+ if (unit)
+ break;
}
+ read_unlock_irqrestore(&adapter->port_list_lock, flags);
- return NULL;
+ return unit;
}
static int zfcp_scsi_slave_alloc(struct scsi_device *sdp)
{
struct zfcp_adapter *adapter;
struct zfcp_unit *unit;
- unsigned long flags;
- int retval = -ENXIO;
+ u64 lun;
adapter = (struct zfcp_adapter *) sdp->host->hostdata[0];
if (!adapter)
goto out;
- read_lock_irqsave(&zfcp_data.config_lock, flags);
- unit = zfcp_unit_lookup(adapter, sdp->channel, sdp->id, sdp->lun);
+ int_to_scsilun(sdp->lun, (struct scsi_lun *)&lun);
+ unit = zfcp_unit_lookup(adapter, sdp->id, lun);
if (unit) {
sdp->hostdata = unit;
unit->device = sdp;
- zfcp_unit_get(unit);
- retval = 0;
+ return 0;
}
- read_unlock_irqrestore(&zfcp_data.config_lock, flags);
out:
- return retval;
+ return -ENXIO;
}
static int zfcp_scsi_eh_abort_handler(struct scsi_cmnd *scpnt)
@@ -338,12 +333,12 @@
if (!shost)
return;
- read_lock_irq(&zfcp_data.config_lock);
- list_for_each_entry(port, &adapter->port_list_head, list)
+ read_lock_irq(&adapter->port_list_lock);
+ list_for_each_entry(port, &adapter->port_list, list)
if (port->rport)
port->rport = NULL;
+ read_unlock_irq(&adapter->port_list_lock);
- read_unlock_irq(&zfcp_data.config_lock);
fc_remove_host(shost);
scsi_remove_host(shost);
scsi_host_put(shost);
@@ -508,7 +503,7 @@
* @rport: The FC rport where to teminate I/O
*
* Abort all pending SCSI commands for a port by closing the
- * port. Using a reopen for avoids a conflict with a shutdown
+ * port. Using a reopen avoiding a conflict with a shutdown
* overwriting a reopen.
*/
static void zfcp_scsi_terminate_rport_io(struct fc_rport *rport)
@@ -518,11 +513,7 @@
struct zfcp_adapter *adapter =
(struct zfcp_adapter *)shost->hostdata[0];
- write_lock_irq(&zfcp_data.config_lock);
port = zfcp_get_port_by_wwpn(adapter, rport->port_name);
- if (port)
- zfcp_port_get(port);
- write_unlock_irq(&zfcp_data.config_lock);
if (port) {
zfcp_erp_port_reopen(port, 0, "sctrpi1", NULL);
@@ -589,10 +580,13 @@
void zfcp_scsi_schedule_rports_block(struct zfcp_adapter *adapter)
{
+ unsigned long flags;
struct zfcp_port *port;
- list_for_each_entry(port, &adapter->port_list_head, list)
+ read_lock_irqsave(&adapter->port_list_lock, flags);
+ list_for_each_entry(port, &adapter->port_list, list)
zfcp_scsi_schedule_rport_block(port);
+ read_unlock_irqrestore(&adapter->port_list_lock, flags);
}
void zfcp_scsi_rport_work(struct work_struct *work)