1 files changed, 714 insertions, 0 deletions

diff --git a/drivers/scsi/libsas/sas_init.c b/drivers/scsi/libsas/sas_init.c
new file mode 100644
index 000000000..e4f77072a
--- /dev/null
+++ b/drivers/scsi/libsas/sas_init.c
@@ -0,0 +1,714 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Serial Attached SCSI (SAS) Transport Layer initialization
+ *
+ * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
+ * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/spinlock.h>
+#include <scsi/sas_ata.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_transport.h>
+#include <scsi/scsi_transport_sas.h>
+
+#include "sas_internal.h"
+
+#include "scsi_sas_internal.h"
+
+static struct kmem_cache *sas_task_cache;
+static struct kmem_cache *sas_event_cache;
+
+struct sas_task *sas_alloc_task(gfp_t flags)
+{
+	struct sas_task *task = kmem_cache_zalloc(sas_task_cache, flags);
+
+	if (task) {
+		spin_lock_init(&task->task_state_lock);
+		task->task_state_flags = SAS_TASK_STATE_PENDING;
+	}
+
+	return task;
+}
+EXPORT_SYMBOL_GPL(sas_alloc_task);
+
+struct sas_task *sas_alloc_slow_task(gfp_t flags)
+{
+	struct sas_task *task = sas_alloc_task(flags);
+	struct sas_task_slow *slow = kmalloc(sizeof(*slow), flags);
+
+	if (!task || !slow) {
+		if (task)
+			kmem_cache_free(sas_task_cache, task);
+		kfree(slow);
+		return NULL;
+	}
+
+	task->slow_task = slow;
+	slow->task = task;
+	timer_setup(&slow->timer, NULL, 0);
+	init_completion(&slow->completion);
+
+	return task;
+}
+EXPORT_SYMBOL_GPL(sas_alloc_slow_task);
+
+void sas_free_task(struct sas_task *task)
+{
+	if (task) {
+		kfree(task->slow_task);
+		kmem_cache_free(sas_task_cache, task);
+	}
+}
+EXPORT_SYMBOL_GPL(sas_free_task);
+
+/*------------ SAS addr hash -----------*/
+void sas_hash_addr(u8 *hashed, const u8 *sas_addr)
+{
+	const u32 poly = 0x00DB2777;
+	u32 r = 0;
+	int i;
+
+	for (i = 0; i < SAS_ADDR_SIZE; i++) {
+		int b;
+
+		for (b = (SAS_ADDR_SIZE - 1); b >= 0; b--) {
+			r <<= 1;
+			if ((1 << b) & sas_addr[i]) {
+				if (!(r & 0x01000000))
+					r ^= poly;
+			} else if (r & 0x01000000) {
+				r ^= poly;
+			}
+		}
+	}
+
+	hashed[0] = (r >> 16) & 0xFF;
+	hashed[1] = (r >> 8) & 0xFF;
+	hashed[2] = r & 0xFF;
+}
+
+int sas_register_ha(struct sas_ha_struct *sas_ha)
+{
+	char name[64];
+	int error = 0;
+
+	mutex_init(&sas_ha->disco_mutex);
+	spin_lock_init(&sas_ha->phy_port_lock);
+	sas_hash_addr(sas_ha->hashed_sas_addr, sas_ha->sas_addr);
+
+	set_bit(SAS_HA_REGISTERED, &sas_ha->state);
+	spin_lock_init(&sas_ha->lock);
+	mutex_init(&sas_ha->drain_mutex);
+	init_waitqueue_head(&sas_ha->eh_wait_q);
+	INIT_LIST_HEAD(&sas_ha->defer_q);
+	INIT_LIST_HEAD(&sas_ha->eh_dev_q);
+
+	sas_ha->event_thres = SAS_PHY_SHUTDOWN_THRES;
+
+	error = sas_register_phys(sas_ha);
+	if (error) {
+		pr_notice("couldn't register sas phys:%d\n", error);
+		return error;
+	}
+
+	error = sas_register_ports(sas_ha);
+	if (error) {
+		pr_notice("couldn't register sas ports:%d\n", error);
+		goto Undo_phys;
+	}
+
+	error = -ENOMEM;
+	snprintf(name, sizeof(name), "%s_event_q", dev_name(sas_ha->dev));
+	sas_ha->event_q = create_singlethread_workqueue(name);
+	if (!sas_ha->event_q)
+		goto Undo_ports;
+
+	snprintf(name, sizeof(name), "%s_disco_q", dev_name(sas_ha->dev));
+	sas_ha->disco_q = create_singlethread_workqueue(name);
+	if (!sas_ha->disco_q)
+		goto Undo_event_q;
+
+	INIT_LIST_HEAD(&sas_ha->eh_done_q);
+	INIT_LIST_HEAD(&sas_ha->eh_ata_q);
+
+	return 0;
+
+Undo_event_q:
+	destroy_workqueue(sas_ha->event_q);
+Undo_ports:
+	sas_unregister_ports(sas_ha);
+Undo_phys:
+
+	return error;
+}
+EXPORT_SYMBOL_GPL(sas_register_ha);
+
+static void sas_disable_events(struct sas_ha_struct *sas_ha)
+{
+	/* Set the state to unregistered to avoid further unchained
+	 * events to be queued, and flush any in-progress drainers
+	 */
+	mutex_lock(&sas_ha->drain_mutex);
+	spin_lock_irq(&sas_ha->lock);
+	clear_bit(SAS_HA_REGISTERED, &sas_ha->state);
+	spin_unlock_irq(&sas_ha->lock);
+	__sas_drain_work(sas_ha);
+	mutex_unlock(&sas_ha->drain_mutex);
+}
+
+int sas_unregister_ha(struct sas_ha_struct *sas_ha)
+{
+	sas_disable_events(sas_ha);
+	sas_unregister_ports(sas_ha);
+
+	/* flush unregistration work */
+	mutex_lock(&sas_ha->drain_mutex);
+	__sas_drain_work(sas_ha);
+	mutex_unlock(&sas_ha->drain_mutex);
+
+	destroy_workqueue(sas_ha->disco_q);
+	destroy_workqueue(sas_ha->event_q);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(sas_unregister_ha);
+
+static int sas_get_linkerrors(struct sas_phy *phy)
+{
+	if (scsi_is_sas_phy_local(phy)) {
+		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
+		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
+		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
+		struct sas_internal *i =
+			to_sas_internal(sas_ha->core.shost->transportt);
+
+		return i->dft->lldd_control_phy(asd_phy, PHY_FUNC_GET_EVENTS, NULL);
+	}
+
+	return sas_smp_get_phy_events(phy);
+}
+
+int sas_try_ata_reset(struct asd_sas_phy *asd_phy)
+{
+	struct domain_device *dev = NULL;
+
+	/* try to route user requested link resets through libata */
+	if (asd_phy->port)
+		dev = asd_phy->port->port_dev;
+
+	/* validate that dev has been probed */
+	if (dev)
+		dev = sas_find_dev_by_rphy(dev->rphy);
+
+	if (dev && dev_is_sata(dev)) {
+		sas_ata_schedule_reset(dev);
+		sas_ata_wait_eh(dev);
+		return 0;
+	}
+
+	return -ENODEV;
+}
+
+/*
+ * transport_sas_phy_reset - reset a phy and permit libata to manage the link
+ *
+ * phy reset request via sysfs in host workqueue context so we know we
+ * can block on eh and safely traverse the domain_device topology
+ */
+static int transport_sas_phy_reset(struct sas_phy *phy, int hard_reset)
+{
+	enum phy_func reset_type;
+
+	if (hard_reset)
+		reset_type = PHY_FUNC_HARD_RESET;
+	else
+		reset_type = PHY_FUNC_LINK_RESET;
+
+	if (scsi_is_sas_phy_local(phy)) {
+		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
+		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
+		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
+		struct sas_internal *i =
+			to_sas_internal(sas_ha->core.shost->transportt);
+
+		if (!hard_reset && sas_try_ata_reset(asd_phy) == 0)
+			return 0;
+		return i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
+	} else {
+		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
+		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
+		struct domain_device *ata_dev = sas_ex_to_ata(ddev, phy->number);
+
+		if (ata_dev && !hard_reset) {
+			sas_ata_schedule_reset(ata_dev);
+			sas_ata_wait_eh(ata_dev);
+			return 0;
+		} else
+			return sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
+	}
+}
+
+int sas_phy_enable(struct sas_phy *phy, int enable)
+{
+	int ret;
+	enum phy_func cmd;
+
+	if (enable)
+		cmd = PHY_FUNC_LINK_RESET;
+	else
+		cmd = PHY_FUNC_DISABLE;
+
+	if (scsi_is_sas_phy_local(phy)) {
+		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
+		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
+		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
+		struct sas_internal *i =
+			to_sas_internal(sas_ha->core.shost->transportt);
+
+		if (enable)
+			ret = transport_sas_phy_reset(phy, 0);
+		else
+			ret = i->dft->lldd_control_phy(asd_phy, cmd, NULL);
+	} else {
+		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
+		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
+
+		if (enable)
+			ret = transport_sas_phy_reset(phy, 0);
+		else
+			ret = sas_smp_phy_control(ddev, phy->number, cmd, NULL);
+	}
+	return ret;
+}
+EXPORT_SYMBOL_GPL(sas_phy_enable);
+
+int sas_phy_reset(struct sas_phy *phy, int hard_reset)
+{
+	int ret;
+	enum phy_func reset_type;
+
+	if (!phy->enabled)
+		return -ENODEV;
+
+	if (hard_reset)
+		reset_type = PHY_FUNC_HARD_RESET;
+	else
+		reset_type = PHY_FUNC_LINK_RESET;
+
+	if (scsi_is_sas_phy_local(phy)) {
+		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
+		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
+		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
+		struct sas_internal *i =
+			to_sas_internal(sas_ha->core.shost->transportt);
+
+		ret = i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
+	} else {
+		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
+		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
+		ret = sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
+	}
+	return ret;
+}
+EXPORT_SYMBOL_GPL(sas_phy_reset);
+
+int sas_set_phy_speed(struct sas_phy *phy,
+		      struct sas_phy_linkrates *rates)
+{
+	int ret;
+
+	if ((rates->minimum_linkrate &&
+	     rates->minimum_linkrate > phy->maximum_linkrate) ||
+	    (rates->maximum_linkrate &&
+	     rates->maximum_linkrate < phy->minimum_linkrate))
+		return -EINVAL;
+
+	if (rates->minimum_linkrate &&
+	    rates->minimum_linkrate < phy->minimum_linkrate_hw)
+		rates->minimum_linkrate = phy->minimum_linkrate_hw;
+
+	if (rates->maximum_linkrate &&
+	    rates->maximum_linkrate > phy->maximum_linkrate_hw)
+		rates->maximum_linkrate = phy->maximum_linkrate_hw;
+
+	if (scsi_is_sas_phy_local(phy)) {
+		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
+		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
+		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
+		struct sas_internal *i =
+			to_sas_internal(sas_ha->core.shost->transportt);
+
+		ret = i->dft->lldd_control_phy(asd_phy, PHY_FUNC_SET_LINK_RATE,
+					       rates);
+	} else {
+		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
+		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
+		ret = sas_smp_phy_control(ddev, phy->number,
+					  PHY_FUNC_LINK_RESET, rates);
+
+	}
+
+	return ret;
+}
+
+void sas_prep_resume_ha(struct sas_ha_struct *ha)
+{
+	int i;
+
+	set_bit(SAS_HA_REGISTERED, &ha->state);
+	set_bit(SAS_HA_RESUMING, &ha->state);
+
+	/* clear out any stale link events/data from the suspension path */
+	for (i = 0; i < ha->num_phys; i++) {
+		struct asd_sas_phy *phy = ha->sas_phy[i];
+
+		memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
+		phy->frame_rcvd_size = 0;
+	}
+}
+EXPORT_SYMBOL(sas_prep_resume_ha);
+
+static int phys_suspended(struct sas_ha_struct *ha)
+{
+	int i, rc = 0;
+
+	for (i = 0; i < ha->num_phys; i++) {
+		struct asd_sas_phy *phy = ha->sas_phy[i];
+
+		if (phy->suspended)
+			rc++;
+	}
+
+	return rc;
+}
+
+static void sas_resume_insert_broadcast_ha(struct sas_ha_struct *ha)
+{
+	int i;
+
+	for (i = 0; i < ha->num_phys; i++) {
+		struct asd_sas_port *port = ha->sas_port[i];
+		struct domain_device *dev = port->port_dev;
+
+		if (dev && dev_is_expander(dev->dev_type)) {
+			struct asd_sas_phy *first_phy;
+
+			spin_lock(&port->phy_list_lock);
+			first_phy = list_first_entry_or_null(
+				&port->phy_list, struct asd_sas_phy,
+				port_phy_el);
+			spin_unlock(&port->phy_list_lock);
+
+			if (first_phy)
+				sas_notify_port_event(first_phy,
+					PORTE_BROADCAST_RCVD, GFP_KERNEL);
+		}
+	}
+}
+
+static void _sas_resume_ha(struct sas_ha_struct *ha, bool drain)
+{
+	const unsigned long tmo = msecs_to_jiffies(25000);
+	int i;
+
+	/* deform ports on phys that did not resume
+	 * at this point we may be racing the phy coming back (as posted
+	 * by the lldd).  So we post the event and once we are in the
+	 * libsas context check that the phy remains suspended before
+	 * tearing it down.
+	 */
+	i = phys_suspended(ha);
+	if (i)
+		dev_info(ha->dev, "waiting up to 25 seconds for %d phy%s to resume\n",
+			 i, i > 1 ? "s" : "");
+	wait_event_timeout(ha->eh_wait_q, phys_suspended(ha) == 0, tmo);
+	for (i = 0; i < ha->num_phys; i++) {
+		struct asd_sas_phy *phy = ha->sas_phy[i];
+
+		if (phy->suspended) {
+			dev_warn(&phy->phy->dev, "resume timeout\n");
+			sas_notify_phy_event(phy, PHYE_RESUME_TIMEOUT,
+					     GFP_KERNEL);
+		}
+	}
+
+	/* all phys are back up or timed out, turn on i/o so we can
+	 * flush out disks that did not return
+	 */
+	scsi_unblock_requests(ha->core.shost);
+	if (drain)
+		sas_drain_work(ha);
+	clear_bit(SAS_HA_RESUMING, &ha->state);
+
+	sas_queue_deferred_work(ha);
+	/* send event PORTE_BROADCAST_RCVD to identify some new inserted
+	 * disks for expander
+	 */
+	sas_resume_insert_broadcast_ha(ha);
+}
+
+void sas_resume_ha(struct sas_ha_struct *ha)
+{
+	_sas_resume_ha(ha, true);
+}
+EXPORT_SYMBOL(sas_resume_ha);
+
+/* A no-sync variant, which does not call sas_drain_ha(). */
+void sas_resume_ha_no_sync(struct sas_ha_struct *ha)
+{
+	_sas_resume_ha(ha, false);
+}
+EXPORT_SYMBOL(sas_resume_ha_no_sync);
+
+void sas_suspend_ha(struct sas_ha_struct *ha)
+{
+	int i;
+
+	sas_disable_events(ha);
+	scsi_block_requests(ha->core.shost);
+	for (i = 0; i < ha->num_phys; i++) {
+		struct asd_sas_port *port = ha->sas_port[i];
+
+		sas_discover_event(port, DISCE_SUSPEND);
+	}
+
+	/* flush suspend events while unregistered */
+	mutex_lock(&ha->drain_mutex);
+	__sas_drain_work(ha);
+	mutex_unlock(&ha->drain_mutex);
+}
+EXPORT_SYMBOL(sas_suspend_ha);
+
+static void sas_phy_release(struct sas_phy *phy)
+{
+	kfree(phy->hostdata);
+	phy->hostdata = NULL;
+}
+
+static void phy_reset_work(struct work_struct *work)
+{
+	struct sas_phy_data *d = container_of(work, typeof(*d), reset_work.work);
+
+	d->reset_result = transport_sas_phy_reset(d->phy, d->hard_reset);
+}
+
+static void phy_enable_work(struct work_struct *work)
+{
+	struct sas_phy_data *d = container_of(work, typeof(*d), enable_work.work);
+
+	d->enable_result = sas_phy_enable(d->phy, d->enable);
+}
+
+static int sas_phy_setup(struct sas_phy *phy)
+{
+	struct sas_phy_data *d = kzalloc(sizeof(*d), GFP_KERNEL);
+
+	if (!d)
+		return -ENOMEM;
+
+	mutex_init(&d->event_lock);
+	INIT_SAS_WORK(&d->reset_work, phy_reset_work);
+	INIT_SAS_WORK(&d->enable_work, phy_enable_work);
+	d->phy = phy;
+	phy->hostdata = d;
+
+	return 0;
+}
+
+static int queue_phy_reset(struct sas_phy *phy, int hard_reset)
+{
+	struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
+	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
+	struct sas_phy_data *d = phy->hostdata;
+	int rc;
+
+	if (!d)
+		return -ENOMEM;
+
+	pm_runtime_get_sync(ha->dev);
+	/* libsas workqueue coordinates ata-eh reset with discovery */
+	mutex_lock(&d->event_lock);
+	d->reset_result = 0;
+	d->hard_reset = hard_reset;
+
+	spin_lock_irq(&ha->lock);
+	sas_queue_work(ha, &d->reset_work);
+	spin_unlock_irq(&ha->lock);
+
+	rc = sas_drain_work(ha);
+	if (rc == 0)
+		rc = d->reset_result;
+	mutex_unlock(&d->event_lock);
+	pm_runtime_put_sync(ha->dev);
+
+	return rc;
+}
+
+static int queue_phy_enable(struct sas_phy *phy, int enable)
+{
+	struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
+	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
+	struct sas_phy_data *d = phy->hostdata;
+	int rc;
+
+	if (!d)
+		return -ENOMEM;
+
+	pm_runtime_get_sync(ha->dev);
+	/* libsas workqueue coordinates ata-eh reset with discovery */
+	mutex_lock(&d->event_lock);
+	d->enable_result = 0;
+	d->enable = enable;
+
+	spin_lock_irq(&ha->lock);
+	sas_queue_work(ha, &d->enable_work);
+	spin_unlock_irq(&ha->lock);
+
+	rc = sas_drain_work(ha);
+	if (rc == 0)
+		rc = d->enable_result;
+	mutex_unlock(&d->event_lock);
+	pm_runtime_put_sync(ha->dev);
+
+	return rc;
+}
+
+static struct sas_function_template sft = {
+	.phy_enable = queue_phy_enable,
+	.phy_reset = queue_phy_reset,
+	.phy_setup = sas_phy_setup,
+	.phy_release = sas_phy_release,
+	.set_phy_speed = sas_set_phy_speed,
+	.get_linkerrors = sas_get_linkerrors,
+	.smp_handler = sas_smp_handler,
+};
+
+static inline ssize_t phy_event_threshold_show(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	struct Scsi_Host *shost = class_to_shost(dev);
+	struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost);
+
+	return scnprintf(buf, PAGE_SIZE, "%u\n", sha->event_thres);
+}
+
+static inline ssize_t phy_event_threshold_store(struct device *dev,
+			struct device_attribute *attr,
+			const char *buf, size_t count)
+{
+	struct Scsi_Host *shost = class_to_shost(dev);
+	struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost);
+
+	sha->event_thres = simple_strtol(buf, NULL, 10);
+
+	/* threshold cannot be set too small */
+	if (sha->event_thres < 32)
+		sha->event_thres = 32;
+
+	return count;
+}
+
+DEVICE_ATTR(phy_event_threshold,
+	S_IRUGO|S_IWUSR,
+	phy_event_threshold_show,
+	phy_event_threshold_store);
+EXPORT_SYMBOL_GPL(dev_attr_phy_event_threshold);
+
+struct scsi_transport_template *
+sas_domain_attach_transport(struct sas_domain_function_template *dft)
+{
+	struct scsi_transport_template *stt = sas_attach_transport(&sft);
+	struct sas_internal *i;
+
+	if (!stt)
+		return stt;
+
+	i = to_sas_internal(stt);
+	i->dft = dft;
+	stt->create_work_queue = 1;
+	stt->eh_strategy_handler = sas_scsi_recover_host;
+
+	return stt;
+}
+EXPORT_SYMBOL_GPL(sas_domain_attach_transport);
+
+struct asd_sas_event *sas_alloc_event(struct asd_sas_phy *phy,
+				      gfp_t gfp_flags)
+{
+	struct asd_sas_event *event;
+	struct sas_ha_struct *sas_ha = phy->ha;
+	struct sas_internal *i =
+		to_sas_internal(sas_ha->core.shost->transportt);
+
+	event = kmem_cache_zalloc(sas_event_cache, gfp_flags);
+	if (!event)
+		return NULL;
+
+	atomic_inc(&phy->event_nr);
+
+	if (atomic_read(&phy->event_nr) > phy->ha->event_thres) {
+		if (i->dft->lldd_control_phy) {
+			if (cmpxchg(&phy->in_shutdown, 0, 1) == 0) {
+				pr_notice("The phy%d bursting events, shut it down.\n",
+					  phy->id);
+				sas_notify_phy_event(phy, PHYE_SHUTDOWN,
+						     gfp_flags);
+			}
+		} else {
+			/* Do not support PHY control, stop allocating events */
+			WARN_ONCE(1, "PHY control not supported.\n");
+			kmem_cache_free(sas_event_cache, event);
+			atomic_dec(&phy->event_nr);
+			event = NULL;
+		}
+	}
+
+	return event;
+}
+
+void sas_free_event(struct asd_sas_event *event)
+{
+	struct asd_sas_phy *phy = event->phy;
+
+	kmem_cache_free(sas_event_cache, event);
+	atomic_dec(&phy->event_nr);
+}
+
+/* ---------- SAS Class register/unregister ---------- */
+
+static int __init sas_class_init(void)
+{
+	sas_task_cache = KMEM_CACHE(sas_task, SLAB_HWCACHE_ALIGN);
+	if (!sas_task_cache)
+		goto out;
+
+	sas_event_cache = KMEM_CACHE(asd_sas_event, SLAB_HWCACHE_ALIGN);
+	if (!sas_event_cache)
+		goto free_task_kmem;
+
+	return 0;
+free_task_kmem:
+	kmem_cache_destroy(sas_task_cache);
+out:
+	return -ENOMEM;
+}
+
+static void __exit sas_class_exit(void)
+{
+	kmem_cache_destroy(sas_task_cache);
+	kmem_cache_destroy(sas_event_cache);
+}
+
+MODULE_AUTHOR("Luben Tuikov <luben_tuikov@adaptec.com>");
+MODULE_DESCRIPTION("SAS Transport Layer");
+MODULE_LICENSE("GPL v2");
+
+module_init(sas_class_init);
+module_exit(sas_class_exit);
+