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author | Swen Schillig <swen@vnet.ibm.com> | 2009-11-24 16:54:00 +0100 |
---|---|---|
committer | James Bottomley <James.Bottomley@suse.de> | 2009-12-04 12:02:02 -0600 |
commit | de3dc57214a1466034ecc4d4ffb10331d34c09a3 (patch) | |
tree | 63eb490d66f9db2cf032041392fb2f4d5ac4785c /drivers/s390/scsi/zfcp_ccw.c | |
parent | f3450c7b917201bb49d67032e9f60d5125675d6a (diff) | |
download | op-kernel-dev-de3dc57214a1466034ecc4d4ffb10331d34c09a3.zip op-kernel-dev-de3dc57214a1466034ecc4d4ffb10331d34c09a3.tar.gz |
[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>
Diffstat (limited to 'drivers/s390/scsi/zfcp_ccw.c')
-rw-r--r-- | drivers/s390/scsi/zfcp_ccw.c | 138 |
1 files changed, 76 insertions, 62 deletions
diff --git a/drivers/s390/scsi/zfcp_ccw.c b/drivers/s390/scsi/zfcp_ccw.c index c89dbe2..2433eac 100644 --- a/drivers/s390/scsi/zfcp_ccw.c +++ b/drivers/s390/scsi/zfcp_ccw.c @@ -13,20 +13,42 @@ #define ZFCP_MODEL_PRIV 0x4 +static DEFINE_SPINLOCK(zfcp_ccw_adapter_ref_lock); + +struct zfcp_adapter *zfcp_ccw_adapter_by_cdev(struct ccw_device *cdev) +{ + struct zfcp_adapter *adapter; + unsigned long flags; + + spin_lock_irqsave(&zfcp_ccw_adapter_ref_lock, flags); + adapter = dev_get_drvdata(&cdev->dev); + if (adapter) + kref_get(&adapter->ref); + spin_unlock_irqrestore(&zfcp_ccw_adapter_ref_lock, flags); + return adapter; +} + +void zfcp_ccw_adapter_put(struct zfcp_adapter *adapter) +{ + unsigned long flags; + + spin_lock_irqsave(&zfcp_ccw_adapter_ref_lock, flags); + kref_put(&adapter->ref, zfcp_adapter_release); + spin_unlock_irqrestore(&zfcp_ccw_adapter_ref_lock, flags); +} + static int zfcp_ccw_suspend(struct ccw_device *cdev) { - struct zfcp_adapter *adapter = dev_get_drvdata(&cdev->dev); + struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev); if (!adapter) return 0; - mutex_lock(&zfcp_data.config_mutex); - zfcp_erp_adapter_shutdown(adapter, 0, "ccsusp1", NULL); zfcp_erp_wait(adapter); - mutex_unlock(&zfcp_data.config_mutex); + zfcp_ccw_adapter_put(adapter); return 0; } @@ -34,7 +56,7 @@ static int zfcp_ccw_suspend(struct ccw_device *cdev) static int zfcp_ccw_activate(struct ccw_device *cdev) { - struct zfcp_adapter *adapter = dev_get_drvdata(&cdev->dev); + struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev); if (!adapter) return 0; @@ -46,6 +68,8 @@ static int zfcp_ccw_activate(struct ccw_device *cdev) zfcp_erp_wait(adapter); flush_work(&adapter->scan_work); + zfcp_ccw_adapter_put(adapter); + return 0; } @@ -67,28 +91,28 @@ int zfcp_ccw_priv_sch(struct zfcp_adapter *adapter) /** * zfcp_ccw_probe - probe function of zfcp driver - * @ccw_device: pointer to belonging ccw device + * @cdev: pointer to belonging ccw device * * This function gets called by the common i/o layer for each FCP * device found on the current system. This is only a stub to make cio * work: To only allocate adapter resources for devices actually used, * the allocation is deferred to the first call to ccw_set_online. */ -static int zfcp_ccw_probe(struct ccw_device *ccw_device) +static int zfcp_ccw_probe(struct ccw_device *cdev) { return 0; } /** * zfcp_ccw_remove - remove function of zfcp driver - * @ccw_device: pointer to belonging ccw device + * @cdev: pointer to belonging ccw device * * This function gets called by the common i/o layer and removes an adapter * from the system. Task of this function is to get rid of all units and * ports that belong to this adapter. And in addition all resources of this * adapter will be freed too. */ -static void zfcp_ccw_remove(struct ccw_device *ccw_device) +static void zfcp_ccw_remove(struct ccw_device *cdev) { struct zfcp_adapter *adapter; struct zfcp_port *port, *p; @@ -96,22 +120,12 @@ static void zfcp_ccw_remove(struct ccw_device *ccw_device) LIST_HEAD(unit_remove_lh); LIST_HEAD(port_remove_lh); - ccw_device_set_offline(ccw_device); - - mutex_lock(&zfcp_data.config_mutex); - adapter = dev_get_drvdata(&ccw_device->dev); - mutex_unlock(&zfcp_data.config_mutex); + ccw_device_set_offline(cdev); + adapter = zfcp_ccw_adapter_by_cdev(cdev); if (!adapter) return; - cancel_work_sync(&adapter->scan_work); - - mutex_lock(&zfcp_data.config_mutex); - - /* this also removes the scsi devices, so call it first */ - zfcp_adapter_scsi_unregister(adapter); - write_lock_irq(&adapter->port_list_lock); list_for_each_entry_safe(port, p, &adapter->port_list, list) { write_lock(&port->unit_list_lock); @@ -126,7 +140,7 @@ static void zfcp_ccw_remove(struct ccw_device *ccw_device) } atomic_set_mask(ZFCP_STATUS_COMMON_REMOVE, &adapter->status); write_unlock_irq(&adapter->port_list_lock); - mutex_unlock(&zfcp_data.config_mutex); + zfcp_ccw_adapter_put(adapter); /* put from zfcp_ccw_adapter_by_cdev */ list_for_each_entry_safe(unit, u, &unit_remove_lh, list) zfcp_device_unregister(&unit->sysfs_device, @@ -136,12 +150,12 @@ static void zfcp_ccw_remove(struct ccw_device *ccw_device) zfcp_device_unregister(&port->sysfs_device, &zfcp_sysfs_port_attrs); - kref_put(&adapter->ref, zfcp_adapter_release); + zfcp_adapter_unregister(adapter); } /** * zfcp_ccw_set_online - set_online function of zfcp driver - * @ccw_device: pointer to belonging ccw device + * @cdev: pointer to belonging ccw device * * This function gets called by the common i/o layer and sets an * adapter into state online. The first call will allocate all @@ -152,23 +166,20 @@ static void zfcp_ccw_remove(struct ccw_device *ccw_device) * the SCSI stack, that the QDIO queues will be set up and that the * adapter will be opened. */ -static int zfcp_ccw_set_online(struct ccw_device *ccw_device) +static int zfcp_ccw_set_online(struct ccw_device *cdev) { - struct zfcp_adapter *adapter; - int ret = 0; - - mutex_lock(&zfcp_data.config_mutex); - adapter = dev_get_drvdata(&ccw_device->dev); + struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev); if (!adapter) { - ret = zfcp_adapter_enqueue(ccw_device); - if (ret) { - dev_err(&ccw_device->dev, + adapter = zfcp_adapter_enqueue(cdev); + + if (IS_ERR(adapter)) { + dev_err(&cdev->dev, "Setting up data structures for the " "FCP adapter failed\n"); - goto out; + return PTR_ERR(adapter); } - adapter = dev_get_drvdata(&ccw_device->dev); + kref_get(&adapter->ref); } /* initialize request counter */ @@ -180,58 +191,61 @@ static int zfcp_ccw_set_online(struct ccw_device *ccw_device) zfcp_erp_adapter_reopen(adapter, ZFCP_STATUS_COMMON_ERP_FAILED, "ccsonl2", NULL); zfcp_erp_wait(adapter); -out: - mutex_unlock(&zfcp_data.config_mutex); - if (!ret) - flush_work(&adapter->scan_work); - return ret; + + flush_work(&adapter->scan_work); + + zfcp_ccw_adapter_put(adapter); + return 0; } /** * zfcp_ccw_set_offline - set_offline function of zfcp driver - * @ccw_device: pointer to belonging ccw device + * @cdev: pointer to belonging ccw device * * This function gets called by the common i/o layer and sets an adapter * into state offline. */ -static int zfcp_ccw_set_offline(struct ccw_device *ccw_device) +static int zfcp_ccw_set_offline(struct ccw_device *cdev) { - struct zfcp_adapter *adapter; + struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev); + + if (!adapter) + return 0; - mutex_lock(&zfcp_data.config_mutex); - adapter = dev_get_drvdata(&ccw_device->dev); zfcp_erp_adapter_shutdown(adapter, 0, "ccsoff1", NULL); zfcp_erp_wait(adapter); - mutex_unlock(&zfcp_data.config_mutex); + + zfcp_ccw_adapter_put(adapter); return 0; } /** * zfcp_ccw_notify - ccw notify function - * @ccw_device: pointer to belonging ccw device + * @cdev: pointer to belonging ccw device * @event: indicates if adapter was detached or attached * * This function gets called by the common i/o layer if an adapter has gone * or reappeared. */ -static int zfcp_ccw_notify(struct ccw_device *ccw_device, int event) +static int zfcp_ccw_notify(struct ccw_device *cdev, int event) { - struct zfcp_adapter *adapter = dev_get_drvdata(&ccw_device->dev); + struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev); + + if (!adapter) + return 1; switch (event) { case CIO_GONE: - dev_warn(&adapter->ccw_device->dev, - "The FCP device has been detached\n"); + dev_warn(&cdev->dev, "The FCP device has been detached\n"); zfcp_erp_adapter_shutdown(adapter, 0, "ccnoti1", NULL); break; case CIO_NO_PATH: - dev_warn(&adapter->ccw_device->dev, + dev_warn(&cdev->dev, "The CHPID for the FCP device is offline\n"); zfcp_erp_adapter_shutdown(adapter, 0, "ccnoti2", NULL); break; case CIO_OPER: - dev_info(&adapter->ccw_device->dev, - "The FCP device is operational again\n"); + dev_info(&cdev->dev, "The FCP device is operational again\n"); zfcp_erp_modify_adapter_status(adapter, "ccnoti3", NULL, ZFCP_STATUS_COMMON_RUNNING, ZFCP_SET); @@ -239,11 +253,13 @@ static int zfcp_ccw_notify(struct ccw_device *ccw_device, int event) "ccnoti4", NULL); break; case CIO_BOXED: - dev_warn(&adapter->ccw_device->dev, "The FCP device " - "did not respond within the specified time\n"); + dev_warn(&cdev->dev, "The FCP device did not respond within " + "the specified time\n"); zfcp_erp_adapter_shutdown(adapter, 0, "ccnoti5", NULL); break; } + + zfcp_ccw_adapter_put(adapter); return 1; } @@ -253,18 +269,16 @@ static int zfcp_ccw_notify(struct ccw_device *ccw_device, int event) */ static void zfcp_ccw_shutdown(struct ccw_device *cdev) { - struct zfcp_adapter *adapter; + struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev); - mutex_lock(&zfcp_data.config_mutex); - adapter = dev_get_drvdata(&cdev->dev); if (!adapter) - goto out; + return; zfcp_erp_adapter_shutdown(adapter, 0, "ccshut1", NULL); zfcp_erp_wait(adapter); zfcp_erp_thread_kill(adapter); -out: - mutex_unlock(&zfcp_data.config_mutex); + + zfcp_ccw_adapter_put(adapter); } struct ccw_driver zfcp_ccw_driver = { |