/*
* 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 list_head dh_list;
};
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 list_head node;
struct rdac_controller *ctlr;
struct scsi_device *sdev;
#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;
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 unsigned int rdac_failover_get(struct rdac_controller *ctlr,
struct list_head *list,
unsigned char *cdb)
{
struct rdac_mode_common *common;
unsigned data_size;
struct rdac_queue_data *qdata;
u8 *lun_table;
if (ctlr->use_ms10) {
struct rdac_pg_expanded *rdac_pg;
data_size = sizeof(struct rdac_pg_expanded);
rdac_pg = &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 = &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;
}
/* Prepare the command. */
if (ctlr->use_ms10) {
cdb[0] = MODE_SELECT_10;
cdb[7] = data_size >> 8;
cdb[8] = data_size & 0xff;
} else {
cdb[0] = MODE_SELECT;
cdb[4] = data_size;
}
return data_size;
}
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);
INIT_LIST_HEAD(&ctlr->dh_list);
return ctlr;
}
static int get_lun_info(struct scsi_device *sdev, struct rdac_dh_data *h,
char *array_name, u8 *array_id)
{
int err = SCSI_DH_IO, i;
struct c8_inquiry *inqp = &h->inq.c8;
if (!scsi_get_vpd_page(sdev, 0xC8, (unsigned char *)inqp,
sizeof(struct c8_inquiry))) {
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);
err = SCSI_DH_OK;
}
return err;
}
static int check_ownership(struct scsi_device *sdev, struct rdac_dh_data *h)
{
int err = SCSI_DH_IO, access_state;
struct rdac_dh_data *tmp;
struct c9_inquiry *inqp = &h->inq.c9;
h->state = RDAC_STATE_ACTIVE;
if (!scsi_get_vpd_page(sdev, 0xC9, (unsigned char *)inqp,
sizeof(struct c9_inquiry))) {
/* 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;
access_state = SCSI_ACCESS_STATE_OPTIMAL;
} else {
h->lun_state = RDAC_LUN_UNOWNED;
if (h->mode == RDAC_MODE) {
h->state = RDAC_STATE_PASSIVE;
access_state = SCSI_ACCESS_STATE_STANDBY;
} else
access_state = SCSI_ACCESS_STATE_ACTIVE;
}
/* Update path prio*/
if (inqp->path_prio & 0x1) {
h->preferred = RDAC_PREFERRED;
access_state |= SCSI_ACCESS_STATE_PREFERRED;
} else
h->preferred = RDAC_NON_PREFERRED;
rcu_read_lock();
list_for_each_entry_rcu(tmp, &h->ctlr->dh_list, node) {
/* h->sdev should always be valid */
BUG_ON(!tmp->sdev);
tmp->sdev->access_state = access_state;
}
rcu_read_unlock();
err = SCSI_DH_OK;
}
return err;
}
static int initialize_controller(struct scsi_device *sdev,
struct rdac_dh_data *h, char *array_name, u8 *array_id)
{
int err = SCSI_DH_IO, index;
struct c4_inquiry *inqp = &h->inq.c4;
if (!scsi_get_vpd_page(sdev, 0xC4, (unsigned char *)inqp,
sizeof(struct c4_inquiry))) {
/* 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;
else {
h->sdev = sdev;
list_add_rcu(&h->node, &h->ctlr->dh_list);
}
spin_unlock(&list_lock);
err = SCSI_DH_OK;
}
return err;
}
static int set_mode_select(struct scsi_device *sdev, struct rdac_dh_data *h)
{
int err = SCSI_DH_IO;
struct c2_inquiry *inqp = &h->inq.c2;
if (!scsi_get_vpd_page(sdev, 0xC2, (unsigned char *)inqp,
sizeof(struct c2_inquiry))) {
/*
* 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;
err = SCSI_DH_OK;
}
return err;
}
static int mode_select_handle_sense(struct scsi_device *sdev,
struct scsi_sense_hdr *sense_hdr)
{
int err = SCSI_DH_IO;
struct rdac_dh_data *h = sdev->handler_data;
if (!scsi_sense_valid(sense_hdr))
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_IMM_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 scsi_device *sdev = ctlr->ms_sdev;
struct rdac_dh_data *h = sdev->handler_data;
int err = SCSI_DH_OK, retry_cnt = RDAC_RETRY_COUNT;
struct rdac_queue_data *tmp, *qdata;
LIST_HEAD(list);
unsigned char cdb[MAX_COMMAND_SIZE];
struct scsi_sense_hdr sshdr;
unsigned int data_size;
u64 req_flags = REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
REQ_FAILFAST_DRIVER;
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:
memset(cdb, 0, sizeof(cdb));
data_size = rdac_failover_get(ctlr, &list, cdb);
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");
if (scsi_execute(sdev, cdb, DMA_TO_DEVICE, &h->ctlr->mode_select,
data_size, NULL, &sshdr, RDAC_TIMEOUT * HZ,
RDAC_RETRIES, req_flags, 0, NULL)) {
err = mode_select_handle_sense(sdev, &sshdr);
if (err == SCSI_DH_RETRY && retry_cnt--)
goto retry;
if (err == SCSI_DH_IMM_RETRY)
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);
}
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 = sdev->handler_data;
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 = sdev->handler_data;
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 blk_status_t rdac_prep_fn(struct scsi_device *sdev, struct request *req)
{
struct rdac_dh_data *h = sdev->handler_data;
if (h->state != RDAC_STATE_ACTIVE) {
req->rq_flags |= RQF_QUIET;
return BLK_STS_IOERR;
}
return BLK_STS_OK;
}
static int rdac_check_sense(struct scsi_device *sdev,
struct scsi_sense_hdr *sense_hdr)
{
struct rdac_dh_data *h = sdev->handler_data;
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 int 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 SCSI_DH_NOMEM;
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]);
sdev->handler_data = h;
return SCSI_DH_OK;
clean_ctlr:
spin_lock(&list_lock);
kref_put(&h->ctlr->kref, release_controller);
spin_unlock(&list_lock);
failed:
kfree(h);
return err;
}
static void rdac_bus_detach( struct scsi_device *sdev )
{
struct rdac_dh_data *h = sdev->handler_data;
if (h->ctlr && h->ctlr->ms_queued)
flush_workqueue(kmpath_rdacd);
spin_lock(&list_lock);
if (h->ctlr) {
list_del_rcu(&h->node);
kref_put(&h->ctlr->kref, release_controller);
}
spin_unlock(&list_lock);
sdev->handler_data = NULL;
synchronize_rcu();
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,
};
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");