[SCSI] scsi_dh: add lsi rdac device handler
This patch provides the device handler to support the LSI RDAC SCSI
based storage devices.
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/scsi/device_handler/Kconfig b/drivers/scsi/device_handler/Kconfig
index 228241d..404f377 100644
--- a/drivers/scsi/device_handler/Kconfig
+++ b/drivers/scsi/device_handler/Kconfig
@@ -10,3 +10,9 @@
SCSI Device Handlers provide device specific support for
devices utilized in multipath configurations. Say Y here to
select support for specific hardware.
+
+config SCSI_DH_RDAC
+ tristate "LSI RDAC Device Handler"
+ depends on SCSI_DH
+ help
+ If you have a LSI RDAC select y. Otherwise, say N.
diff --git a/drivers/scsi/device_handler/Makefile b/drivers/scsi/device_handler/Makefile
index f306e44..1a42b34 100644
--- a/drivers/scsi/device_handler/Makefile
+++ b/drivers/scsi/device_handler/Makefile
@@ -2,3 +2,4 @@
# SCSI Device Handler
#
obj-$(CONFIG_SCSI_DH) += scsi_dh.o
+obj-$(CONFIG_SCSI_DH_RDAC) += scsi_dh_rdac.o
diff --git a/drivers/scsi/device_handler/scsi_dh_rdac.c b/drivers/scsi/device_handler/scsi_dh_rdac.c
new file mode 100644
index 0000000..6fff077
--- /dev/null
+++ b/drivers/scsi/device_handler/scsi_dh_rdac.c
@@ -0,0 +1,691 @@
+/*
+ * Engenio/LSI RDAC SCSI Device Handler
+ *
+ * Copyright (C) 2005 Mike Christie. All rights reserved.
+ * Copyright (C) Chandra Seetharaman, IBM Corp. 2007
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ */
+#include <scsi/scsi.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_dh.h>
+
+#define RDAC_NAME "rdac"
+
+/*
+ * LSI mode page stuff
+ *
+ * These struct definitions and the forming of the
+ * mode page were taken from the LSI RDAC 2.4 GPL'd
+ * driver, and then converted to Linux conventions.
+ */
+#define RDAC_QUIESCENCE_TIME 20;
+/*
+ * Page Codes
+ */
+#define RDAC_PAGE_CODE_REDUNDANT_CONTROLLER 0x2c
+
+/*
+ * Controller modes definitions
+ */
+#define RDAC_MODE_TRANSFER_SPECIFIED_LUNS 0x02
+
+/*
+ * RDAC Options field
+ */
+#define RDAC_FORCED_QUIESENCE 0x02
+
+#define RDAC_TIMEOUT (60 * HZ)
+#define RDAC_RETRIES 3
+
+struct rdac_mode_6_hdr {
+ u8 data_len;
+ u8 medium_type;
+ u8 device_params;
+ u8 block_desc_len;
+};
+
+struct rdac_mode_10_hdr {
+ u16 data_len;
+ u8 medium_type;
+ u8 device_params;
+ u16 reserved;
+ u16 block_desc_len;
+};
+
+struct rdac_mode_common {
+ u8 controller_serial[16];
+ u8 alt_controller_serial[16];
+ u8 rdac_mode[2];
+ u8 alt_rdac_mode[2];
+ u8 quiescence_timeout;
+ u8 rdac_options;
+};
+
+struct rdac_pg_legacy {
+ struct rdac_mode_6_hdr hdr;
+ u8 page_code;
+ u8 page_len;
+ struct rdac_mode_common common;
+#define MODE6_MAX_LUN 32
+ u8 lun_table[MODE6_MAX_LUN];
+ u8 reserved2[32];
+ u8 reserved3;
+ u8 reserved4;
+};
+
+struct rdac_pg_expanded {
+ struct rdac_mode_10_hdr hdr;
+ u8 page_code;
+ u8 subpage_code;
+ u8 page_len[2];
+ struct rdac_mode_common common;
+ u8 lun_table[256];
+ u8 reserved3;
+ u8 reserved4;
+};
+
+struct c9_inquiry {
+ u8 peripheral_info;
+ u8 page_code; /* 0xC9 */
+ u8 reserved1;
+ u8 page_len;
+ u8 page_id[4]; /* "vace" */
+ u8 avte_cvp;
+ u8 path_prio;
+ u8 reserved2[38];
+};
+
+#define SUBSYS_ID_LEN 16
+#define SLOT_ID_LEN 2
+
+struct c4_inquiry {
+ u8 peripheral_info;
+ u8 page_code; /* 0xC4 */
+ u8 reserved1;
+ u8 page_len;
+ u8 page_id[4]; /* "subs" */
+ u8 subsys_id[SUBSYS_ID_LEN];
+ u8 revision[4];
+ u8 slot_id[SLOT_ID_LEN];
+ u8 reserved[2];
+};
+
+struct rdac_controller {
+ u8 subsys_id[SUBSYS_ID_LEN];
+ u8 slot_id[SLOT_ID_LEN];
+ int use_ms10;
+ struct kref kref;
+ struct list_head node; /* list of all controllers */
+ union {
+ struct rdac_pg_legacy legacy;
+ struct rdac_pg_expanded expanded;
+ } mode_select;
+};
+struct c8_inquiry {
+ u8 peripheral_info;
+ u8 page_code; /* 0xC8 */
+ u8 reserved1;
+ u8 page_len;
+ u8 page_id[4]; /* "edid" */
+ u8 reserved2[3];
+ u8 vol_uniq_id_len;
+ u8 vol_uniq_id[16];
+ u8 vol_user_label_len;
+ u8 vol_user_label[60];
+ u8 array_uniq_id_len;
+ u8 array_unique_id[16];
+ u8 array_user_label_len;
+ u8 array_user_label[60];
+ u8 lun[8];
+};
+
+struct c2_inquiry {
+ u8 peripheral_info;
+ u8 page_code; /* 0xC2 */
+ u8 reserved1;
+ u8 page_len;
+ u8 page_id[4]; /* "swr4" */
+ u8 sw_version[3];
+ u8 sw_date[3];
+ u8 features_enabled;
+ u8 max_lun_supported;
+ u8 partitions[239]; /* Total allocation length should be 0xFF */
+};
+
+struct rdac_dh_data {
+ struct rdac_controller *ctlr;
+#define UNINITIALIZED_LUN (1 << 8)
+ unsigned lun;
+#define RDAC_STATE_ACTIVE 0
+#define RDAC_STATE_PASSIVE 1
+ unsigned char state;
+ unsigned char sense[SCSI_SENSE_BUFFERSIZE];
+ union {
+ struct c2_inquiry c2;
+ struct c4_inquiry c4;
+ struct c8_inquiry c8;
+ struct c9_inquiry c9;
+ } inq;
+};
+
+static LIST_HEAD(ctlr_list);
+static DEFINE_SPINLOCK(list_lock);
+
+static inline struct rdac_dh_data *get_rdac_data(struct scsi_device *sdev)
+{
+ struct scsi_dh_data *scsi_dh_data = sdev->scsi_dh_data;
+ BUG_ON(scsi_dh_data == NULL);
+ return ((struct rdac_dh_data *) scsi_dh_data->buf);
+}
+
+static struct request *get_rdac_req(struct scsi_device *sdev,
+ void *buffer, unsigned buflen, int rw)
+{
+ struct request *rq;
+ struct request_queue *q = sdev->request_queue;
+ struct rdac_dh_data *h = get_rdac_data(sdev);
+
+ rq = blk_get_request(q, rw, GFP_KERNEL);
+
+ if (!rq) {
+ sdev_printk(KERN_INFO, sdev,
+ "get_rdac_req: blk_get_request failed.\n");
+ return NULL;
+ }
+
+ if (buflen && blk_rq_map_kern(q, rq, buffer, buflen, GFP_KERNEL)) {
+ blk_put_request(rq);
+ sdev_printk(KERN_INFO, sdev,
+ "get_rdac_req: blk_rq_map_kern failed.\n");
+ return NULL;
+ }
+
+ memset(&rq->cmd, 0, BLK_MAX_CDB);
+ rq->sense = h->sense;
+ memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
+ rq->sense_len = 0;
+
+ rq->cmd_type = REQ_TYPE_BLOCK_PC;
+ rq->cmd_flags |= REQ_FAILFAST | REQ_NOMERGE;
+ rq->retries = RDAC_RETRIES;
+ rq->timeout = RDAC_TIMEOUT;
+
+ return rq;
+}
+
+static struct request *rdac_failover_get(struct scsi_device *sdev)
+{
+ struct request *rq;
+ struct rdac_mode_common *common;
+ unsigned data_size;
+ struct rdac_dh_data *h = get_rdac_data(sdev);
+
+ if (h->ctlr->use_ms10) {
+ struct rdac_pg_expanded *rdac_pg;
+
+ data_size = sizeof(struct rdac_pg_expanded);
+ rdac_pg = &h->ctlr->mode_select.expanded;
+ memset(rdac_pg, 0, data_size);
+ common = &rdac_pg->common;
+ rdac_pg->page_code = RDAC_PAGE_CODE_REDUNDANT_CONTROLLER + 0x40;
+ rdac_pg->subpage_code = 0x1;
+ rdac_pg->page_len[0] = 0x01;
+ rdac_pg->page_len[1] = 0x28;
+ rdac_pg->lun_table[h->lun] = 0x81;
+ } else {
+ struct rdac_pg_legacy *rdac_pg;
+
+ data_size = sizeof(struct rdac_pg_legacy);
+ rdac_pg = &h->ctlr->mode_select.legacy;
+ memset(rdac_pg, 0, data_size);
+ common = &rdac_pg->common;
+ rdac_pg->page_code = RDAC_PAGE_CODE_REDUNDANT_CONTROLLER;
+ rdac_pg->page_len = 0x68;
+ rdac_pg->lun_table[h->lun] = 0x81;
+ }
+ common->rdac_mode[1] = RDAC_MODE_TRANSFER_SPECIFIED_LUNS;
+ common->quiescence_timeout = RDAC_QUIESCENCE_TIME;
+ common->rdac_options = RDAC_FORCED_QUIESENCE;
+
+ /* get request for block layer packet command */
+ rq = get_rdac_req(sdev, &h->ctlr->mode_select, data_size, WRITE);
+ if (!rq)
+ return NULL;
+
+ /* Prepare the command. */
+ if (h->ctlr->use_ms10) {
+ rq->cmd[0] = MODE_SELECT_10;
+ rq->cmd[7] = data_size >> 8;
+ rq->cmd[8] = data_size & 0xff;
+ } else {
+ rq->cmd[0] = MODE_SELECT;
+ rq->cmd[4] = data_size;
+ }
+ rq->cmd_len = COMMAND_SIZE(rq->cmd[0]);
+
+ return rq;
+}
+
+static void release_controller(struct kref *kref)
+{
+ struct rdac_controller *ctlr;
+ ctlr = container_of(kref, struct rdac_controller, kref);
+
+ spin_lock(&list_lock);
+ list_del(&ctlr->node);
+ spin_unlock(&list_lock);
+ kfree(ctlr);
+}
+
+static struct rdac_controller *get_controller(u8 *subsys_id, u8 *slot_id)
+{
+ struct rdac_controller *ctlr, *tmp;
+
+ spin_lock(&list_lock);
+
+ list_for_each_entry(tmp, &ctlr_list, node) {
+ if ((memcmp(tmp->subsys_id, subsys_id, SUBSYS_ID_LEN) == 0) &&
+ (memcmp(tmp->slot_id, slot_id, SLOT_ID_LEN) == 0)) {
+ kref_get(&tmp->kref);
+ spin_unlock(&list_lock);
+ return tmp;
+ }
+ }
+ ctlr = kmalloc(sizeof(*ctlr), GFP_ATOMIC);
+ if (!ctlr)
+ goto done;
+
+ /* initialize fields of controller */
+ memcpy(ctlr->subsys_id, subsys_id, SUBSYS_ID_LEN);
+ memcpy(ctlr->slot_id, slot_id, SLOT_ID_LEN);
+ kref_init(&ctlr->kref);
+ ctlr->use_ms10 = -1;
+ list_add(&ctlr->node, &ctlr_list);
+done:
+ spin_unlock(&list_lock);
+ return ctlr;
+}
+
+static int submit_inquiry(struct scsi_device *sdev, int page_code,
+ unsigned int len)
+{
+ struct request *rq;
+ struct request_queue *q = sdev->request_queue;
+ struct rdac_dh_data *h = get_rdac_data(sdev);
+ int err = SCSI_DH_RES_TEMP_UNAVAIL;
+
+ rq = get_rdac_req(sdev, &h->inq, len, READ);
+ if (!rq)
+ goto done;
+
+ /* Prepare the command. */
+ rq->cmd[0] = INQUIRY;
+ rq->cmd[1] = 1;
+ rq->cmd[2] = page_code;
+ rq->cmd[4] = len;
+ rq->cmd_len = COMMAND_SIZE(INQUIRY);
+ err = blk_execute_rq(q, NULL, rq, 1);
+ if (err == -EIO)
+ err = SCSI_DH_IO;
+done:
+ return err;
+}
+
+static int get_lun(struct scsi_device *sdev)
+{
+ int err;
+ struct c8_inquiry *inqp;
+ struct rdac_dh_data *h = get_rdac_data(sdev);
+
+ err = submit_inquiry(sdev, 0xC8, sizeof(struct c8_inquiry));
+ if (err == SCSI_DH_OK) {
+ inqp = &h->inq.c8;
+ h->lun = inqp->lun[7]; /* currently it uses only one byte */
+ }
+ return err;
+}
+
+#define RDAC_OWNED 0
+#define RDAC_UNOWNED 1
+#define RDAC_FAILED 2
+static int check_ownership(struct scsi_device *sdev)
+{
+ int err;
+ struct c9_inquiry *inqp;
+ struct rdac_dh_data *h = get_rdac_data(sdev);
+
+ err = submit_inquiry(sdev, 0xC9, sizeof(struct c9_inquiry));
+ if (err == SCSI_DH_OK) {
+ err = RDAC_UNOWNED;
+ inqp = &h->inq.c9;
+ /*
+ * If in AVT mode or if the path already owns the LUN,
+ * return RDAC_OWNED;
+ */
+ if (((inqp->avte_cvp >> 7) == 0x1) ||
+ ((inqp->avte_cvp & 0x1) != 0))
+ err = RDAC_OWNED;
+ } else
+ err = RDAC_FAILED;
+ return err;
+}
+
+static int initialize_controller(struct scsi_device *sdev)
+{
+ int err;
+ struct c4_inquiry *inqp;
+ struct rdac_dh_data *h = get_rdac_data(sdev);
+
+ err = submit_inquiry(sdev, 0xC4, sizeof(struct c4_inquiry));
+ if (err == SCSI_DH_OK) {
+ inqp = &h->inq.c4;
+ h->ctlr = get_controller(inqp->subsys_id, inqp->slot_id);
+ if (!h->ctlr)
+ err = SCSI_DH_RES_TEMP_UNAVAIL;
+ }
+ return err;
+}
+
+static int set_mode_select(struct scsi_device *sdev)
+{
+ int err;
+ struct c2_inquiry *inqp;
+ struct rdac_dh_data *h = get_rdac_data(sdev);
+
+ err = submit_inquiry(sdev, 0xC2, sizeof(struct c2_inquiry));
+ if (err == SCSI_DH_OK) {
+ inqp = &h->inq.c2;
+ /*
+ * If more than MODE6_MAX_LUN luns are supported, use
+ * mode select 10
+ */
+ if (inqp->max_lun_supported >= MODE6_MAX_LUN)
+ h->ctlr->use_ms10 = 1;
+ else
+ h->ctlr->use_ms10 = 0;
+ }
+ return err;
+}
+
+static int mode_select_handle_sense(struct scsi_device *sdev)
+{
+ struct scsi_sense_hdr sense_hdr;
+ struct rdac_dh_data *h = get_rdac_data(sdev);
+ int sense, err = SCSI_DH_IO, ret;
+
+ ret = scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE, &sense_hdr);
+ if (!ret)
+ goto done;
+
+ err = SCSI_DH_OK;
+ sense = (sense_hdr.sense_key << 16) | (sense_hdr.asc << 8) |
+ sense_hdr.ascq;
+ /* If it is retryable failure, submit the c9 inquiry again */
+ if (sense == 0x59136 || sense == 0x68b02 || sense == 0xb8b02 ||
+ sense == 0x62900) {
+ /* 0x59136 - Command lock contention
+ * 0x[6b]8b02 - Quiesense in progress or achieved
+ * 0x62900 - Power On, Reset, or Bus Device Reset
+ */
+ err = SCSI_DH_RETRY;
+ }
+
+ if (sense)
+ sdev_printk(KERN_INFO, sdev,
+ "MODE_SELECT failed with sense 0x%x.\n", sense);
+done:
+ return err;
+}
+
+static int send_mode_select(struct scsi_device *sdev)
+{
+ struct request *rq;
+ struct request_queue *q = sdev->request_queue;
+ struct rdac_dh_data *h = get_rdac_data(sdev);
+ int err = SCSI_DH_RES_TEMP_UNAVAIL;
+
+ rq = rdac_failover_get(sdev);
+ if (!rq)
+ goto done;
+
+ sdev_printk(KERN_INFO, sdev, "queueing MODE_SELECT command.\n");
+
+ err = blk_execute_rq(q, NULL, rq, 1);
+ if (err != SCSI_DH_OK)
+ err = mode_select_handle_sense(sdev);
+ if (err == SCSI_DH_OK)
+ h->state = RDAC_STATE_ACTIVE;
+done:
+ return err;
+}
+
+static int rdac_activate(struct scsi_device *sdev)
+{
+ struct rdac_dh_data *h = get_rdac_data(sdev);
+ int err = SCSI_DH_OK;
+
+ if (h->lun == UNINITIALIZED_LUN) {
+ err = get_lun(sdev);
+ if (err != SCSI_DH_OK)
+ goto done;
+ }
+
+ err = check_ownership(sdev);
+ switch (err) {
+ case RDAC_UNOWNED:
+ break;
+ case RDAC_OWNED:
+ err = SCSI_DH_OK;
+ goto done;
+ case RDAC_FAILED:
+ default:
+ err = SCSI_DH_IO;
+ goto done;
+ }
+
+ if (!h->ctlr) {
+ err = initialize_controller(sdev);
+ if (err != SCSI_DH_OK)
+ goto done;
+ }
+
+ if (h->ctlr->use_ms10 == -1) {
+ err = set_mode_select(sdev);
+ if (err != SCSI_DH_OK)
+ goto done;
+ }
+
+ err = send_mode_select(sdev);
+done:
+ return err;
+}
+
+static int rdac_prep_fn(struct scsi_device *sdev, struct request *req)
+{
+ struct rdac_dh_data *h = get_rdac_data(sdev);
+ int ret = BLKPREP_OK;
+
+ if (h->state != RDAC_STATE_ACTIVE) {
+ ret = BLKPREP_KILL;
+ req->cmd_flags |= REQ_QUIET;
+ }
+ return ret;
+
+}
+
+static int rdac_check_sense(struct scsi_device *sdev,
+ struct scsi_sense_hdr *sense_hdr)
+{
+ struct rdac_dh_data *h = get_rdac_data(sdev);
+ switch (sense_hdr->sense_key) {
+ case NOT_READY:
+ if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x81)
+ /* LUN Not Ready - Storage firmware incompatible
+ * Manual code synchonisation required.
+ *
+ * Nothing we can do here. Try to bypass the path.
+ */
+ return SUCCESS;
+ if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0xA1)
+ /* LUN Not Ready - Quiescense in progress
+ *
+ * Just retry and wait.
+ */
+ return NEEDS_RETRY;
+ break;
+ case ILLEGAL_REQUEST:
+ if (sense_hdr->asc == 0x94 && sense_hdr->ascq == 0x01) {
+ /* Invalid Request - Current Logical Unit Ownership.
+ * Controller is not the current owner of the LUN,
+ * Fail the path, so that the other path be used.
+ */
+ h->state = RDAC_STATE_PASSIVE;
+ return SUCCESS;
+ }
+ break;
+ case UNIT_ATTENTION:
+ if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00)
+ /*
+ * Power On, Reset, or Bus Device Reset, just retry.
+ */
+ return NEEDS_RETRY;
+ break;
+ }
+ /* success just means we do not care what scsi-ml does */
+ return SCSI_RETURN_NOT_HANDLED;
+}
+
+static const struct {
+ char *vendor;
+ char *model;
+} rdac_dev_list[] = {
+ {"IBM", "1722"},
+ {"IBM", "1724"},
+ {"IBM", "1726"},
+ {"IBM", "1742"},
+ {"IBM", "1814"},
+ {"IBM", "1815"},
+ {"IBM", "1818"},
+ {"IBM", "3526"},
+ {"SGI", "TP9400"},
+ {"SGI", "TP9500"},
+ {"SGI", "IS"},
+ {"STK", "OPENstorage D280"},
+ {"SUN", "CSM200_R"},
+ {"SUN", "LCSM100_F"},
+ {NULL, NULL},
+};
+
+static int rdac_bus_notify(struct notifier_block *, unsigned long, void *);
+
+static struct scsi_device_handler rdac_dh = {
+ .name = RDAC_NAME,
+ .module = THIS_MODULE,
+ .nb.notifier_call = rdac_bus_notify,
+ .prep_fn = rdac_prep_fn,
+ .check_sense = rdac_check_sense,
+ .activate = rdac_activate,
+};
+
+/*
+ * TODO: need some interface so we can set trespass values
+ */
+static int rdac_bus_notify(struct notifier_block *nb,
+ unsigned long action, void *data)
+{
+ struct device *dev = data;
+ struct scsi_device *sdev = to_scsi_device(dev);
+ struct scsi_dh_data *scsi_dh_data;
+ struct rdac_dh_data *h;
+ int i, found = 0;
+ unsigned long flags;
+
+ if (action == BUS_NOTIFY_ADD_DEVICE) {
+ for (i = 0; rdac_dev_list[i].vendor; i++) {
+ if (!strncmp(sdev->vendor, rdac_dev_list[i].vendor,
+ strlen(rdac_dev_list[i].vendor)) &&
+ !strncmp(sdev->model, rdac_dev_list[i].model,
+ strlen(rdac_dev_list[i].model))) {
+ found = 1;
+ break;
+ }
+ }
+ if (!found)
+ goto out;
+
+ scsi_dh_data = kzalloc(sizeof(struct scsi_device_handler *)
+ + sizeof(*h) , GFP_KERNEL);
+ if (!scsi_dh_data) {
+ sdev_printk(KERN_ERR, sdev, "Attach failed %s.\n",
+ RDAC_NAME);
+ goto out;
+ }
+
+ scsi_dh_data->scsi_dh = &rdac_dh;
+ h = (struct rdac_dh_data *) scsi_dh_data->buf;
+ h->lun = UNINITIALIZED_LUN;
+ h->state = RDAC_STATE_ACTIVE;
+ spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
+ sdev->scsi_dh_data = scsi_dh_data;
+ spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
+ try_module_get(THIS_MODULE);
+
+ sdev_printk(KERN_NOTICE, sdev, "Attached %s.\n", RDAC_NAME);
+
+ } else if (action == BUS_NOTIFY_DEL_DEVICE) {
+ if (sdev->scsi_dh_data == NULL ||
+ sdev->scsi_dh_data->scsi_dh != &rdac_dh)
+ goto out;
+
+ spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
+ scsi_dh_data = sdev->scsi_dh_data;
+ sdev->scsi_dh_data = NULL;
+ spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
+
+ h = (struct rdac_dh_data *) scsi_dh_data->buf;
+ if (h->ctlr)
+ kref_put(&h->ctlr->kref, release_controller);
+ kfree(scsi_dh_data);
+ module_put(THIS_MODULE);
+ sdev_printk(KERN_NOTICE, sdev, "Dettached %s.\n", RDAC_NAME);
+ }
+
+out:
+ return 0;
+}
+
+static int __init rdac_init(void)
+{
+ int r;
+
+ r = scsi_register_device_handler(&rdac_dh);
+ if (r != 0)
+ printk(KERN_ERR "Failed to register scsi device handler.");
+ return r;
+}
+
+static void __exit rdac_exit(void)
+{
+ scsi_unregister_device_handler(&rdac_dh);
+}
+
+module_init(rdac_init);
+module_exit(rdac_exit);
+
+MODULE_DESCRIPTION("Multipath LSI/Engenio RDAC driver");
+MODULE_AUTHOR("Mike Christie, Chandra Seetharaman");
+MODULE_LICENSE("GPL");