Initial import

1 files changed, 937 insertions, 0 deletions

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 000000000..b46ace3d4
--- /dev/null
+++ b/drivers/scsi/device_handler/scsi_dh_rdac.c
@@ -0,0 +1,937 @@
+/*
+ * LSI/Engenio/NetApp E-Series 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>
+#include <linux/workqueue.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+
+#define RDAC_NAME "rdac"
+#define RDAC_RETRY_COUNT 5
+
+/*
+ * 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
+#define ARRAY_LABEL_LEN	31
+
+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];
+};
+
+#define UNIQUE_ID_LEN 16
+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[UNIQUE_ID_LEN];
+	u8	array_user_label_len;
+	u8	array_user_label[60];
+	u8	lun[8];
+};
+
+struct rdac_controller {
+	u8			array_id[UNIQUE_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;
+	u8	index;
+	u8	array_name[ARRAY_LABEL_LEN];
+	struct Scsi_Host	*host;
+	spinlock_t		ms_lock;
+	int			ms_queued;
+	struct work_struct	ms_work;
+	struct scsi_device	*ms_sdev;
+	struct list_head	ms_head;
+};
+
+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 scsi_dh_data	dh_data;
+	struct rdac_controller	*ctlr;
+#define UNINITIALIZED_LUN	(1 << 8)
+	unsigned		lun;
+
+#define RDAC_MODE		0
+#define RDAC_MODE_AVT		1
+#define RDAC_MODE_IOSHIP	2
+	unsigned char		mode;
+
+#define RDAC_STATE_ACTIVE	0
+#define RDAC_STATE_PASSIVE	1
+	unsigned char		state;
+
+#define RDAC_LUN_UNOWNED	0
+#define RDAC_LUN_OWNED		1
+	char			lun_state;
+
+#define RDAC_PREFERRED		0
+#define RDAC_NON_PREFERRED	1
+	char			preferred;
+
+	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 const char *mode[] = {
+	"RDAC",
+	"AVT",
+	"IOSHIP",
+};
+static const char *lun_state[] =
+{
+	"unowned",
+	"owned",
+};
+
+struct rdac_queue_data {
+	struct list_head	entry;
+	struct rdac_dh_data	*h;
+	activate_complete	callback_fn;
+	void			*callback_data;
+};
+
+static LIST_HEAD(ctlr_list);
+static DEFINE_SPINLOCK(list_lock);
+static struct workqueue_struct *kmpath_rdacd;
+static void send_mode_select(struct work_struct *work);
+
+/*
+ * module parameter to enable rdac debug logging.
+ * 2 bits for each type of logging, only two types defined for now
+ * Can be enhanced if required at later point
+ */
+static int rdac_logging = 1;
+module_param(rdac_logging, int, S_IRUGO|S_IWUSR);
+MODULE_PARM_DESC(rdac_logging, "A bit mask of rdac logging levels, "
+		"Default is 1 - failover logging enabled, "
+		"set it to 0xF to enable all the logs");
+
+#define RDAC_LOG_FAILOVER	0
+#define RDAC_LOG_SENSE		2
+
+#define RDAC_LOG_BITS		2
+
+#define RDAC_LOG_LEVEL(SHIFT)  \
+	((rdac_logging >> (SHIFT)) & ((1 << (RDAC_LOG_BITS)) - 1))
+
+#define RDAC_LOG(SHIFT, sdev, f, arg...) \
+do { \
+	if (unlikely(RDAC_LOG_LEVEL(SHIFT))) \
+		sdev_printk(KERN_INFO, sdev, RDAC_NAME ": " f "\n", ## arg); \
+} while (0);
+
+static inline struct rdac_dh_data *get_rdac_data(struct scsi_device *sdev)
+{
+	return container_of(sdev->scsi_dh_data, struct rdac_dh_data, dh_data);
+}
+
+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;
+
+	rq = blk_get_request(q, rw, GFP_NOIO);
+
+	if (IS_ERR(rq)) {
+		sdev_printk(KERN_INFO, sdev,
+				"get_rdac_req: blk_get_request failed.\n");
+		return NULL;
+	}
+	blk_rq_set_block_pc(rq);
+
+	if (buflen && blk_rq_map_kern(q, rq, buffer, buflen, GFP_NOIO)) {
+		blk_put_request(rq);
+		sdev_printk(KERN_INFO, sdev,
+				"get_rdac_req: blk_rq_map_kern failed.\n");
+		return NULL;
+	}
+
+	rq->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
+			 REQ_FAILFAST_DRIVER;
+	rq->retries = RDAC_RETRIES;
+	rq->timeout = RDAC_TIMEOUT;
+
+	return rq;
+}
+
+static struct request *rdac_failover_get(struct scsi_device *sdev,
+			struct rdac_dh_data *h, struct list_head *list)
+{
+	struct request *rq;
+	struct rdac_mode_common *common;
+	unsigned data_size;
+	struct rdac_queue_data *qdata;
+	u8 *lun_table;
+
+	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;
+		lun_table = rdac_pg->lun_table;
+	} 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;
+		lun_table = rdac_pg->lun_table;
+	}
+	common->rdac_mode[1] = RDAC_MODE_TRANSFER_SPECIFIED_LUNS;
+	common->quiescence_timeout = RDAC_QUIESCENCE_TIME;
+	common->rdac_options = RDAC_FORCED_QUIESENCE;
+
+	list_for_each_entry(qdata, list, entry) {
+		lun_table[qdata->h->lun] = 0x81;
+	}
+
+	/* 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]);
+
+	rq->sense = h->sense;
+	memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
+	rq->sense_len = 0;
+
+	return rq;
+}
+
+static void release_controller(struct kref *kref)
+{
+	struct rdac_controller *ctlr;
+	ctlr = container_of(kref, struct rdac_controller, kref);
+
+	list_del(&ctlr->node);
+	kfree(ctlr);
+}
+
+static struct rdac_controller *get_controller(int index, char *array_name,
+			u8 *array_id, struct scsi_device *sdev)
+{
+	struct rdac_controller *ctlr, *tmp;
+
+	list_for_each_entry(tmp, &ctlr_list, node) {
+		if ((memcmp(tmp->array_id, array_id, UNIQUE_ID_LEN) == 0) &&
+			  (tmp->index == index) &&
+			  (tmp->host == sdev->host)) {
+			kref_get(&tmp->kref);
+			return tmp;
+		}
+	}
+	ctlr = kmalloc(sizeof(*ctlr), GFP_ATOMIC);
+	if (!ctlr)
+		return NULL;
+
+	/* initialize fields of controller */
+	memcpy(ctlr->array_id, array_id, UNIQUE_ID_LEN);
+	ctlr->index = index;
+	ctlr->host = sdev->host;
+	memcpy(ctlr->array_name, array_name, ARRAY_LABEL_LEN);
+
+	kref_init(&ctlr->kref);
+	ctlr->use_ms10 = -1;
+	ctlr->ms_queued = 0;
+	ctlr->ms_sdev = NULL;
+	spin_lock_init(&ctlr->ms_lock);
+	INIT_WORK(&ctlr->ms_work, send_mode_select);
+	INIT_LIST_HEAD(&ctlr->ms_head);
+	list_add(&ctlr->node, &ctlr_list);
+
+	return ctlr;
+}
+
+static int submit_inquiry(struct scsi_device *sdev, int page_code,
+			  unsigned int len, struct rdac_dh_data *h)
+{
+	struct request *rq;
+	struct request_queue *q = sdev->request_queue;
+	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);
+
+	rq->sense = h->sense;
+	memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
+	rq->sense_len = 0;
+
+	err = blk_execute_rq(q, NULL, rq, 1);
+	if (err == -EIO)
+		err = SCSI_DH_IO;
+
+	blk_put_request(rq);
+done:
+	return err;
+}
+
+static int get_lun_info(struct scsi_device *sdev, struct rdac_dh_data *h,
+			char *array_name, u8 *array_id)
+{
+	int err, i;
+	struct c8_inquiry *inqp;
+
+	err = submit_inquiry(sdev, 0xC8, sizeof(struct c8_inquiry), h);
+	if (err == SCSI_DH_OK) {
+		inqp = &h->inq.c8;
+		if (inqp->page_code != 0xc8)
+			return SCSI_DH_NOSYS;
+		if (inqp->page_id[0] != 'e' || inqp->page_id[1] != 'd' ||
+		    inqp->page_id[2] != 'i' || inqp->page_id[3] != 'd')
+			return SCSI_DH_NOSYS;
+		h->lun = inqp->lun[7]; /* Uses only the last byte */
+
+		for(i=0; i<ARRAY_LABEL_LEN-1; ++i)
+			*(array_name+i) = inqp->array_user_label[(2*i)+1];
+
+		*(array_name+ARRAY_LABEL_LEN-1) = '\0';
+		memset(array_id, 0, UNIQUE_ID_LEN);
+		memcpy(array_id, inqp->array_unique_id, inqp->array_uniq_id_len);
+	}
+	return err;
+}
+
+static int check_ownership(struct scsi_device *sdev, struct rdac_dh_data *h)
+{
+	int err;
+	struct c9_inquiry *inqp;
+
+	h->state = RDAC_STATE_ACTIVE;
+	err = submit_inquiry(sdev, 0xC9, sizeof(struct c9_inquiry), h);
+	if (err == SCSI_DH_OK) {
+		inqp = &h->inq.c9;
+		/* detect the operating mode */
+		if ((inqp->avte_cvp >> 5) & 0x1)
+			h->mode = RDAC_MODE_IOSHIP; /* LUN in IOSHIP mode */
+		else if (inqp->avte_cvp >> 7)
+			h->mode = RDAC_MODE_AVT; /* LUN in AVT mode */
+		else
+			h->mode = RDAC_MODE; /* LUN in RDAC mode */
+
+		/* Update ownership */
+		if (inqp->avte_cvp & 0x1)
+			h->lun_state = RDAC_LUN_OWNED;
+		else {
+			h->lun_state = RDAC_LUN_UNOWNED;
+			if (h->mode == RDAC_MODE)
+				h->state = RDAC_STATE_PASSIVE;
+		}
+
+		/* Update path prio*/
+		if (inqp->path_prio & 0x1)
+			h->preferred = RDAC_PREFERRED;
+		else
+			h->preferred = RDAC_NON_PREFERRED;
+	}
+
+	return err;
+}
+
+static int initialize_controller(struct scsi_device *sdev,
+		struct rdac_dh_data *h, char *array_name, u8 *array_id)
+{
+	int err, index;
+	struct c4_inquiry *inqp;
+
+	err = submit_inquiry(sdev, 0xC4, sizeof(struct c4_inquiry), h);
+	if (err == SCSI_DH_OK) {
+		inqp = &h->inq.c4;
+		/* get the controller index */
+		if (inqp->slot_id[1] == 0x31)
+			index = 0;
+		else
+			index = 1;
+
+		spin_lock(&list_lock);
+		h->ctlr = get_controller(index, array_name, array_id, sdev);
+		if (!h->ctlr)
+			err = SCSI_DH_RES_TEMP_UNAVAIL;
+		spin_unlock(&list_lock);
+	}
+	return err;
+}
+
+static int set_mode_select(struct scsi_device *sdev, struct rdac_dh_data *h)
+{
+	int err;
+	struct c2_inquiry *inqp;
+
+	err = submit_inquiry(sdev, 0xC2, sizeof(struct c2_inquiry), h);
+	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,
+					unsigned char *sensebuf)
+{
+	struct scsi_sense_hdr sense_hdr;
+	int err = SCSI_DH_IO, ret;
+	struct rdac_dh_data *h = get_rdac_data(sdev);
+
+	ret = scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE, &sense_hdr);
+	if (!ret)
+		goto done;
+
+	switch (sense_hdr.sense_key) {
+	case NO_SENSE:
+	case ABORTED_COMMAND:
+	case UNIT_ATTENTION:
+		err = SCSI_DH_RETRY;
+		break;
+	case NOT_READY:
+		if (sense_hdr.asc == 0x04 && sense_hdr.ascq == 0x01)
+			/* LUN Not Ready and is in the Process of Becoming
+			 * Ready
+			 */
+			err = SCSI_DH_RETRY;
+		break;
+	case ILLEGAL_REQUEST:
+		if (sense_hdr.asc == 0x91 && sense_hdr.ascq == 0x36)
+			/*
+			 * Command Lock contention
+			 */
+			err = SCSI_DH_RETRY;
+		break;
+	default:
+		break;
+	}
+
+	RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, "
+		"MODE_SELECT returned with sense %02x/%02x/%02x",
+		(char *) h->ctlr->array_name, h->ctlr->index,
+		sense_hdr.sense_key, sense_hdr.asc, sense_hdr.ascq);
+
+done:
+	return err;
+}
+
+static void send_mode_select(struct work_struct *work)
+{
+	struct rdac_controller *ctlr =
+		container_of(work, struct rdac_controller, ms_work);
+	struct request *rq;
+	struct scsi_device *sdev = ctlr->ms_sdev;
+	struct rdac_dh_data *h = get_rdac_data(sdev);
+	struct request_queue *q = sdev->request_queue;
+	int err, retry_cnt = RDAC_RETRY_COUNT;
+	struct rdac_queue_data *tmp, *qdata;
+	LIST_HEAD(list);
+
+	spin_lock(&ctlr->ms_lock);
+	list_splice_init(&ctlr->ms_head, &list);
+	ctlr->ms_queued = 0;
+	ctlr->ms_sdev = NULL;
+	spin_unlock(&ctlr->ms_lock);
+
+retry:
+	err = SCSI_DH_RES_TEMP_UNAVAIL;
+	rq = rdac_failover_get(sdev, h, &list);
+	if (!rq)
+		goto done;
+
+	RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, "
+		"%s MODE_SELECT command",
+		(char *) h->ctlr->array_name, h->ctlr->index,
+		(retry_cnt == RDAC_RETRY_COUNT) ? "queueing" : "retrying");
+
+	err = blk_execute_rq(q, NULL, rq, 1);
+	blk_put_request(rq);
+	if (err != SCSI_DH_OK) {
+		err = mode_select_handle_sense(sdev, h->sense);
+		if (err == SCSI_DH_RETRY && retry_cnt--)
+			goto retry;
+	}
+	if (err == SCSI_DH_OK) {
+		h->state = RDAC_STATE_ACTIVE;
+		RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, "
+				"MODE_SELECT completed",
+				(char *) h->ctlr->array_name, h->ctlr->index);
+	}
+
+done:
+	list_for_each_entry_safe(qdata, tmp, &list, entry) {
+		list_del(&qdata->entry);
+		if (err == SCSI_DH_OK)
+			qdata->h->state = RDAC_STATE_ACTIVE;
+		if (qdata->callback_fn)
+			qdata->callback_fn(qdata->callback_data, err);
+		kfree(qdata);
+	}
+	return;
+}
+
+static int queue_mode_select(struct scsi_device *sdev,
+				activate_complete fn, void *data)
+{
+	struct rdac_queue_data *qdata;
+	struct rdac_controller *ctlr;
+
+	qdata = kzalloc(sizeof(*qdata), GFP_KERNEL);
+	if (!qdata)
+		return SCSI_DH_RETRY;
+
+	qdata->h = get_rdac_data(sdev);
+	qdata->callback_fn = fn;
+	qdata->callback_data = data;
+
+	ctlr = qdata->h->ctlr;
+	spin_lock(&ctlr->ms_lock);
+	list_add_tail(&qdata->entry, &ctlr->ms_head);
+	if (!ctlr->ms_queued) {
+		ctlr->ms_queued = 1;
+		ctlr->ms_sdev = sdev;
+		queue_work(kmpath_rdacd, &ctlr->ms_work);
+	}
+	spin_unlock(&ctlr->ms_lock);
+	return SCSI_DH_OK;
+}
+
+static int rdac_activate(struct scsi_device *sdev,
+			activate_complete fn, void *data)
+{
+	struct rdac_dh_data *h = get_rdac_data(sdev);
+	int err = SCSI_DH_OK;
+	int act = 0;
+
+	err = check_ownership(sdev, h);
+	if (err != SCSI_DH_OK)
+		goto done;
+
+	switch (h->mode) {
+	case RDAC_MODE:
+		if (h->lun_state == RDAC_LUN_UNOWNED)
+			act = 1;
+		break;
+	case RDAC_MODE_IOSHIP:
+		if ((h->lun_state == RDAC_LUN_UNOWNED) &&
+		    (h->preferred == RDAC_PREFERRED))
+			act = 1;
+		break;
+	default:
+		break;
+	}
+
+	if (act) {
+		err = queue_mode_select(sdev, fn, data);
+		if (err == SCSI_DH_OK)
+			return 0;
+	}
+done:
+	if (fn)
+		fn(data, err);
+	return 0;
+}
+
+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);
+
+	RDAC_LOG(RDAC_LOG_SENSE, sdev, "array %s, ctlr %d, "
+			"I/O returned with sense %02x/%02x/%02x",
+			(char *) h->ctlr->array_name, h->ctlr->index,
+			sense_hdr->sense_key, sense_hdr->asc, sense_hdr->ascq);
+
+	switch (sense_hdr->sense_key) {
+	case NOT_READY:
+		if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x01)
+			/* LUN Not Ready - Logical Unit Not Ready and is in
+			* the process of becoming ready
+			* Just retry.
+			*/
+			return ADD_TO_MLQUEUE;
+		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 ADD_TO_MLQUEUE;
+		if (sense_hdr->asc == 0xA1  && sense_hdr->ascq == 0x02)
+			/* LUN Not Ready - Quiescense in progress
+			 * or has been achieved
+			 * Just retry.
+			 */
+			return ADD_TO_MLQUEUE;
+		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 ADD_TO_MLQUEUE;
+		if (sense_hdr->asc == 0x8b && sense_hdr->ascq == 0x02)
+			/*
+			 * Quiescence in progress , just retry.
+			 */
+			return ADD_TO_MLQUEUE;
+		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", "1745"},
+	{"IBM", "1746"},
+	{"IBM", "1813"},
+	{"IBM", "1814"},
+	{"IBM", "1815"},
+	{"IBM", "1818"},
+	{"IBM", "3526"},
+	{"SGI", "TP9"},
+	{"SGI", "IS"},
+	{"STK", "OPENstorage D280"},
+	{"STK", "FLEXLINE 380"},
+	{"SUN", "CSM"},
+	{"SUN", "LCSM100"},
+	{"SUN", "STK6580_6780"},
+	{"SUN", "SUN_6180"},
+	{"SUN", "ArrayStorage"},
+	{"DELL", "MD3"},
+	{"NETAPP", "INF-01-00"},
+	{"LSI", "INF-01-00"},
+	{"ENGENIO", "INF-01-00"},
+	{NULL, NULL},
+};
+
+static bool rdac_match(struct scsi_device *sdev)
+{
+	int i;
+
+	if (scsi_device_tpgs(sdev))
+		return false;
+
+	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))) {
+			return true;
+		}
+	}
+	return false;
+}
+
+static struct scsi_dh_data *rdac_bus_attach(struct scsi_device *sdev)
+{
+	struct rdac_dh_data *h;
+	int err;
+	char array_name[ARRAY_LABEL_LEN];
+	char array_id[UNIQUE_ID_LEN];
+
+	h = kzalloc(sizeof(*h) , GFP_KERNEL);
+	if (!h)
+		return ERR_PTR(-ENOMEM);
+	h->lun = UNINITIALIZED_LUN;
+	h->state = RDAC_STATE_ACTIVE;
+
+	err = get_lun_info(sdev, h, array_name, array_id);
+	if (err != SCSI_DH_OK)
+		goto failed;
+
+	err = initialize_controller(sdev, h, array_name, array_id);
+	if (err != SCSI_DH_OK)
+		goto failed;
+
+	err = check_ownership(sdev, h);
+	if (err != SCSI_DH_OK)
+		goto clean_ctlr;
+
+	err = set_mode_select(sdev, h);
+	if (err != SCSI_DH_OK)
+		goto clean_ctlr;
+
+	sdev_printk(KERN_NOTICE, sdev,
+		    "%s: LUN %d (%s) (%s)\n",
+		    RDAC_NAME, h->lun, mode[(int)h->mode],
+		    lun_state[(int)h->lun_state]);
+
+	return &h->dh_data;
+
+clean_ctlr:
+	spin_lock(&list_lock);
+	kref_put(&h->ctlr->kref, release_controller);
+	spin_unlock(&list_lock);
+
+failed:
+	kfree(h);
+	return ERR_PTR(-EINVAL);
+}
+
+static void rdac_bus_detach( struct scsi_device *sdev )
+{
+	struct rdac_dh_data *h = get_rdac_data(sdev);
+
+	if (h->ctlr && h->ctlr->ms_queued)
+		flush_workqueue(kmpath_rdacd);
+
+	spin_lock(&list_lock);
+	if (h->ctlr)
+		kref_put(&h->ctlr->kref, release_controller);
+	spin_unlock(&list_lock);
+	kfree(h);
+}
+
+static struct scsi_device_handler rdac_dh = {
+	.name = RDAC_NAME,
+	.module = THIS_MODULE,
+	.prep_fn = rdac_prep_fn,
+	.check_sense = rdac_check_sense,
+	.attach = rdac_bus_attach,
+	.detach = rdac_bus_detach,
+	.activate = rdac_activate,
+	.match = rdac_match,
+};
+
+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.");
+		goto done;
+	}
+
+	/*
+	 * Create workqueue to handle mode selects for rdac
+	 */
+	kmpath_rdacd = create_singlethread_workqueue("kmpath_rdacd");
+	if (!kmpath_rdacd) {
+		scsi_unregister_device_handler(&rdac_dh);
+		printk(KERN_ERR "kmpath_rdacd creation failed.\n");
+
+		r = -EINVAL;
+	}
+done:
+	return r;
+}
+
+static void __exit rdac_exit(void)
+{
+	destroy_workqueue(kmpath_rdacd);
+	scsi_unregister_device_handler(&rdac_dh);
+}
+
+module_init(rdac_init);
+module_exit(rdac_exit);
+
+MODULE_DESCRIPTION("Multipath LSI/Engenio/NetApp E-Series RDAC driver");
+MODULE_AUTHOR("Mike Christie, Chandra Seetharaman");
+MODULE_VERSION("01.00.0000.0000");
+MODULE_LICENSE("GPL");