[SCSI] zfcp: Remove global config_mutex
The global config_mutex was required for the serialization of a
configuration change within the zfcp driver. This global locking is
now obsolete and can be removed. The requirement of serializing the
access to a zfcp_adapter reference via a ccw_device is realized wth a
static spinlock.
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_aux.c b/drivers/s390/scsi/zfcp_aux.c
index 8492cea..ed31bd0 100644
--- a/drivers/s390/scsi/zfcp_aux.c
+++ b/drivers/s390/scsi/zfcp_aux.c
@@ -80,23 +80,21 @@
static void __init zfcp_init_device_configure(char *busid, u64 wwpn, u64 lun)
{
- struct ccw_device *ccwdev;
+ struct ccw_device *cdev;
struct zfcp_adapter *adapter;
struct zfcp_port *port;
struct zfcp_unit *unit;
- ccwdev = get_ccwdev_by_busid(&zfcp_ccw_driver, busid);
- if (!ccwdev)
+ cdev = get_ccwdev_by_busid(&zfcp_ccw_driver, busid);
+ if (!cdev)
return;
- if (ccw_device_set_online(ccwdev))
- goto out_ccwdev;
+ if (ccw_device_set_online(cdev))
+ goto out_ccw_device;
- mutex_lock(&zfcp_data.config_mutex);
- adapter = dev_get_drvdata(&ccwdev->dev);
+ adapter = zfcp_ccw_adapter_by_cdev(cdev);
if (!adapter)
- goto out_unlock;
- kref_get(&adapter->ref);
+ goto out_ccw_device;
port = zfcp_get_port_by_wwpn(adapter, wwpn);
if (!port)
@@ -105,21 +103,17 @@
unit = zfcp_unit_enqueue(port, lun);
if (IS_ERR(unit))
goto out_unit;
- mutex_unlock(&zfcp_data.config_mutex);
zfcp_erp_unit_reopen(unit, 0, "auidc_1", NULL);
zfcp_erp_wait(adapter);
flush_work(&unit->scsi_work);
- mutex_lock(&zfcp_data.config_mutex);
out_unit:
put_device(&port->sysfs_device);
out_port:
- kref_put(&adapter->ref, zfcp_adapter_release);
-out_unlock:
- mutex_unlock(&zfcp_data.config_mutex);
-out_ccwdev:
- put_device(&ccwdev->dev);
+ zfcp_ccw_adapter_put(adapter);
+out_ccw_device:
+ put_device(&cdev->dev);
return;
}
@@ -184,8 +178,6 @@
if (!zfcp_data.gid_pn_cache)
goto out_gid_cache;
- mutex_init(&zfcp_data.config_mutex);
-
zfcp_data.scsi_transport_template =
fc_attach_transport(&zfcp_transport_functions);
if (!zfcp_data.scsi_transport_template)
@@ -296,7 +288,6 @@
* @port: pointer to port where unit is added
* @fcp_lun: FCP LUN of unit to be enqueued
* Returns: pointer to enqueued unit on success, ERR_PTR on error
- * Locks: config_mutex must be held to serialize changes to the unit list
*
* Sets up some unit internal structures and creates sysfs entry.
*/
@@ -371,7 +362,6 @@
static int zfcp_allocate_low_mem_buffers(struct zfcp_adapter *adapter)
{
- /* must only be called with zfcp_data.config_mutex taken */
adapter->pool.erp_req =
mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
if (!adapter->pool.erp_req)
@@ -419,7 +409,6 @@
static void zfcp_free_low_mem_buffers(struct zfcp_adapter *adapter)
{
- /* zfcp_data.config_mutex must be held */
if (adapter->pool.erp_req)
mempool_destroy(adapter->pool.erp_req);
if (adapter->pool.scsi_req)
@@ -501,24 +490,22 @@
* zfcp_adapter_enqueue - enqueue a new adapter to the list
* @ccw_device: pointer to the struct cc_device
*
- * Returns: 0 if a new adapter was successfully enqueued
- * -ENOMEM if alloc failed
+ * Returns: struct zfcp_adapter*
* Enqueues an adapter at the end of the adapter list in the driver data.
* All adapter internal structures are set up.
* Proc-fs entries are also created.
- * locks: config_mutex must be held to serialize changes to the adapter list
*/
-int zfcp_adapter_enqueue(struct ccw_device *ccw_device)
+struct zfcp_adapter *zfcp_adapter_enqueue(struct ccw_device *ccw_device)
{
struct zfcp_adapter *adapter;
if (!get_device(&ccw_device->dev))
- return -ENODEV;
+ return ERR_PTR(-ENODEV);
adapter = kzalloc(sizeof(struct zfcp_adapter), GFP_KERNEL);
if (!adapter) {
put_device(&ccw_device->dev);
- return -ENOMEM;
+ return ERR_PTR(-ENOMEM);
}
kref_init(&adapter->ref);
@@ -578,11 +565,30 @@
atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &adapter->status);
if (!zfcp_adapter_scsi_register(adapter))
- return 0;
+ return adapter;
failed:
- kref_put(&adapter->ref, zfcp_adapter_release);
- return -ENOMEM;
+ zfcp_adapter_unregister(adapter);
+ return ERR_PTR(-ENOMEM);
+}
+
+void zfcp_adapter_unregister(struct zfcp_adapter *adapter)
+{
+ struct ccw_device *cdev = adapter->ccw_device;
+
+ cancel_work_sync(&adapter->scan_work);
+ cancel_work_sync(&adapter->stat_work);
+ zfcp_destroy_adapter_work_queue(adapter);
+
+ zfcp_fc_wka_ports_force_offline(adapter->gs);
+ zfcp_adapter_scsi_unregister(adapter);
+ sysfs_remove_group(&cdev->dev.kobj, &zfcp_sysfs_adapter_attrs);
+
+ zfcp_erp_thread_kill(adapter);
+ zfcp_dbf_adapter_unregister(adapter->dbf);
+ zfcp_qdio_destroy(adapter->qdio);
+
+ zfcp_ccw_adapter_put(adapter); /* final put to release */
}
/**
@@ -594,27 +600,16 @@
{
struct zfcp_adapter *adapter = container_of(ref, struct zfcp_adapter,
ref);
- struct ccw_device *ccw_device = adapter->ccw_device;
-
- cancel_work_sync(&adapter->stat_work);
-
- zfcp_fc_wka_ports_force_offline(adapter->gs);
- sysfs_remove_group(&ccw_device->dev.kobj, &zfcp_sysfs_adapter_attrs);
-
- dev_set_drvdata(&ccw_device->dev, NULL);
+ struct ccw_device *cdev = adapter->ccw_device;
dev_set_drvdata(&adapter->ccw_device->dev, NULL);
zfcp_fc_gs_destroy(adapter);
- zfcp_erp_thread_kill(adapter);
- zfcp_destroy_adapter_work_queue(adapter);
- zfcp_dbf_adapter_unregister(adapter->dbf);
zfcp_free_low_mem_buffers(adapter);
- zfcp_qdio_destroy(adapter->qdio);
kfree(adapter->req_list);
kfree(adapter->fc_stats);
kfree(adapter->stats_reset_data);
kfree(adapter);
- put_device(&ccw_device->dev);
+ put_device(&cdev->dev);
}
/**
@@ -636,7 +631,7 @@
struct zfcp_port *port = container_of(dev, struct zfcp_port,
sysfs_device);
- kref_put(&port->adapter->ref, zfcp_adapter_release);
+ zfcp_ccw_adapter_put(port->adapter);
kfree(port);
}
@@ -647,7 +642,6 @@
* @status: initial status for the port
* @d_id: destination id of the remote port to be enqueued
* Returns: pointer to enqueued port on success, ERR_PTR on error
- * Locks: config_mutex must be held to serialize changes to the port list
*
* All port internal structures are set up and the sysfs entry is generated.
* d_id is used to enqueue ports with a well known address like the Directory
@@ -718,7 +712,7 @@
err_out_put:
device_unregister(&port->sysfs_device);
err_out:
- kref_put(&adapter->ref, zfcp_adapter_release);
+ zfcp_ccw_adapter_put(adapter);
return ERR_PTR(retval);
}