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[SCSI] scsi_dh: Implement common device table handling 

Instead of having each and every driver implement its own
device table scanning code we should rather implement a common
routine and scan the device tables there.
This allows us also to implement a general notifier chain
callback for all device handler instead for one per handler.

[sekharan: Fix rejections caused by conflicting bug fix]
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
This commit is contained in:
Hannes Reinecke 2008-07-17 16:52:51 -07:00 committed by James Bottomley
parent 6d49f63b41
commit 765cbc6dad
5 changed files with 305 additions and 228 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

202
drivers/scsi/device_handler/scsi_dh.c
View File

@ -33,7 +33,7 @@ static struct scsi_device_handler *get_device_handler(const char *name)
spin_lock(&list_lock);
list_for_each_entry(tmp, &scsi_dh_list, list) {
if (!strcmp(tmp->name, name)) {
if (!strncmp(tmp->name, name, strlen(tmp->name))) {
found = tmp;
break;
}
@ -42,11 +42,147 @@ static struct scsi_device_handler *get_device_handler(const char *name)
return found;
}
static int device_handler_match(struct scsi_device_handler *tmp,
struct scsi_device *sdev)
{
int i;
for(i = 0; tmp->devlist[i].vendor; i++) {
if (!strncmp(sdev->vendor, tmp->devlist[i].vendor,
strlen(tmp->devlist[i].vendor)) &&
!strncmp(sdev->model, tmp->devlist[i].model,
strlen(tmp->devlist[i].model))) {
return 1;
}
}
return 0;
}
/*
* scsi_dh_handler_attach - Attach a device handler to a device
* @sdev - SCSI device the device handler should attach to
* @scsi_dh - The device handler to attach
*/
static int scsi_dh_handler_attach(struct scsi_device *sdev,
struct scsi_device_handler *scsi_dh)
{
int err = 0;
if (sdev->scsi_dh_data) {
if (sdev->scsi_dh_data->scsi_dh != scsi_dh)
err = -EBUSY;
} else if (scsi_dh->attach)
err = scsi_dh->attach(sdev);
return err;
}
/*
* scsi_dh_handler_detach - Detach a device handler from a device
* @sdev - SCSI device the device handler should be detached from
* @scsi_dh - Device handler to be detached
*
* Detach from a device handler. If a device handler is specified,
* only detach if the currently attached handler is equal to it.
*/
static void scsi_dh_handler_detach(struct scsi_device *sdev,
struct scsi_device_handler *scsi_dh)
{
if (!sdev->scsi_dh_data)
return;
if (scsi_dh && scsi_dh != sdev->scsi_dh_data->scsi_dh)
return;
if (!scsi_dh)
scsi_dh = sdev->scsi_dh_data->scsi_dh;
if (scsi_dh && scsi_dh->detach)
scsi_dh->detach(sdev);
}
/*
* scsi_dh_notifier - notifier chain callback
*/
static int scsi_dh_notifier(struct notifier_block *nb,
unsigned long action, void *data)
{
struct device *dev = data;
struct scsi_device *sdev;
int err = 0;
struct scsi_device_handler *tmp, *devinfo = NULL;
if (!scsi_is_sdev_device(dev))
return 0;
sdev = to_scsi_device(dev);
spin_lock(&list_lock);
list_for_each_entry(tmp, &scsi_dh_list, list) {
if (device_handler_match(tmp, sdev)) {
devinfo = tmp;
break;
}
}
spin_unlock(&list_lock);
if (!devinfo)
goto out;
if (action == BUS_NOTIFY_ADD_DEVICE) {
err = scsi_dh_handler_attach(sdev, devinfo);
} else if (action == BUS_NOTIFY_DEL_DEVICE) {
scsi_dh_handler_detach(sdev, NULL);
}
out:
return err;
}
/*
* scsi_dh_notifier_add - Callback for scsi_register_device_handler
*/
static int scsi_dh_notifier_add(struct device *dev, void *data)
{
struct scsi_device_handler *scsi_dh = data;
struct scsi_device *sdev;
if (!scsi_is_sdev_device(dev))
return 0;
if (!get_device(dev))
return 0;
sdev = to_scsi_device(dev);
if (device_handler_match(scsi_dh, sdev))
scsi_dh_handler_attach(sdev, scsi_dh);
put_device(dev);
return 0;
}
/*
* scsi_dh_notifier_remove - Callback for scsi_unregister_device_handler
*/
static int scsi_dh_notifier_remove(struct device *dev, void *data)
{
struct scsi_device_handler *scsi_dh = data;
struct scsi_device *sdev;
if (!scsi_is_sdev_device(dev))
return 0;
if (!get_device(dev))
return 0;
sdev = to_scsi_device(dev);
scsi_dh_handler_detach(sdev, scsi_dh);
put_device(dev);
scsi_dh->nb.notifier_call(&scsi_dh->nb, BUS_NOTIFY_ADD_DEVICE, dev);
return 0;
}
@ -59,33 +195,19 @@ static int scsi_dh_notifier_add(struct device *dev, void *data)
*/
int scsi_register_device_handler(struct scsi_device_handler *scsi_dh)
{
int ret = -EBUSY;
struct scsi_device_handler *tmp;
if (get_device_handler(scsi_dh->name))
return -EBUSY;
tmp = get_device_handler(scsi_dh->name);
if (tmp)
goto done;
ret = bus_register_notifier(&scsi_bus_type, &scsi_dh->nb);
bus_for_each_dev(&scsi_bus_type, NULL, scsi_dh, scsi_dh_notifier_add);
spin_lock(&list_lock);
list_add(&scsi_dh->list, &scsi_dh_list);
spin_unlock(&list_lock);
bus_for_each_dev(&scsi_bus_type, NULL, scsi_dh, scsi_dh_notifier_add);
printk(KERN_INFO "%s: device handler registered\n", scsi_dh->name);
done:
return ret;
return SCSI_DH_OK;
}
EXPORT_SYMBOL_GPL(scsi_register_device_handler);
static int scsi_dh_notifier_remove(struct device *dev, void *data)
{
struct scsi_device_handler *scsi_dh = data;
scsi_dh->nb.notifier_call(&scsi_dh->nb, BUS_NOTIFY_DEL_DEVICE, dev);
return 0;
}
/*
* scsi_unregister_device_handler - register a device handler personality
* module.
@ -95,23 +217,18 @@ static int scsi_dh_notifier_remove(struct device *dev, void *data)
*/
int scsi_unregister_device_handler(struct scsi_device_handler *scsi_dh)
{
int ret = -ENODEV;
struct scsi_device_handler *tmp;
tmp = get_device_handler(scsi_dh->name);
if (!tmp)
goto done;
ret = bus_unregister_notifier(&scsi_bus_type, &scsi_dh->nb);
if (!get_device_handler(scsi_dh->name))
return -ENODEV;
bus_for_each_dev(&scsi_bus_type, NULL, scsi_dh,
scsi_dh_notifier_remove);
scsi_dh_notifier_remove);
spin_lock(&list_lock);
list_del(&scsi_dh->list);
spin_unlock(&list_lock);
printk(KERN_INFO "%s: device handler unregistered\n", scsi_dh->name);
done:
return ret;
return SCSI_DH_OK;
}
EXPORT_SYMBOL_GPL(scsi_unregister_device_handler);
@ -157,6 +274,27 @@ int scsi_dh_handler_exist(const char *name)
}
EXPORT_SYMBOL_GPL(scsi_dh_handler_exist);
static struct notifier_block scsi_dh_nb = {
.notifier_call = scsi_dh_notifier
};
static int __init scsi_dh_init(void)
{
int r;
r = bus_register_notifier(&scsi_bus_type, &scsi_dh_nb);
return r;
}
static void __exit scsi_dh_exit(void)
{
bus_unregister_notifier(&scsi_bus_type, &scsi_dh_nb);
}
module_init(scsi_dh_init);
module_exit(scsi_dh_exit);
MODULE_DESCRIPTION("SCSI device handler");
MODULE_AUTHOR("Chandra Seetharaman <sekharan@us.ibm.com>");
MODULE_LICENSE("GPL");

117
drivers/scsi/device_handler/scsi_dh_emc.c
View File

@ -238,12 +238,12 @@ static int sp_info_endio(struct scsi_device *sdev, int result,
}
/*
* Get block request for REQ_BLOCK_PC command issued to path. Currently
* limited to MODE_SELECT (trespass) and INQUIRY (VPD page 0xC0) commands.
*
* Uses data and sense buffers in hardware handler context structure and
* assumes serial servicing of commands, both issuance and completion.
*/
* Get block request for REQ_BLOCK_PC command issued to path. Currently
* limited to MODE_SELECT (trespass) and INQUIRY (VPD page 0xC0) commands.
*
* Uses data and sense buffers in hardware handler context structure and
* assumes serial servicing of commands, both issuance and completion.
*/
static struct request *get_req(struct scsi_device *sdev, int cmd)
{
struct clariion_dh_data *csdev = get_clariion_data(sdev);
@ -390,21 +390,21 @@ static int clariion_check_sense(struct scsi_device *sdev,
return SUCCESS;
}
static const struct {
char *vendor;
char *model;
} clariion_dev_list[] = {
const struct scsi_dh_devlist clariion_dev_list[] = {
{"DGC", "RAID"},
{"DGC", "DISK"},
{NULL, NULL},
};
static int clariion_bus_notify(struct notifier_block *, unsigned long, void *);
static int clariion_bus_attach(struct scsi_device *sdev);
static void clariion_bus_detach(struct scsi_device *sdev);
static struct scsi_device_handler clariion_dh = {
.name = CLARIION_NAME,
.module = THIS_MODULE,
.nb.notifier_call = clariion_bus_notify,
.devlist = clariion_dev_list,
.attach = clariion_bus_attach,
.detach = clariion_bus_detach,
.check_sense = clariion_check_sense,
.activate = clariion_activate,
};
@ -412,75 +412,52 @@ static struct scsi_device_handler clariion_dh = {
/*
* TODO: need some interface so we can set trespass values
*/
static int clariion_bus_notify(struct notifier_block *nb,
unsigned long action, void *data)
static int clariion_bus_attach(struct scsi_device *sdev)
{
struct device *dev = data;
struct scsi_device *sdev;
struct scsi_dh_data *scsi_dh_data;
struct clariion_dh_data *h;
int i, found = 0;
unsigned long flags;
if (!scsi_is_sdev_device(dev))
return 0;
sdev = to_scsi_device(dev);
if (action == BUS_NOTIFY_ADD_DEVICE) {
for (i = 0; clariion_dev_list[i].vendor; i++) {
if (!strncmp(sdev->vendor, clariion_dev_list[i].vendor,
strlen(clariion_dev_list[i].vendor)) &&
!strncmp(sdev->model, clariion_dev_list[i].model,
strlen(clariion_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",
CLARIION_NAME);
goto out;
}
scsi_dh_data->scsi_dh = &clariion_dh;
h = (struct clariion_dh_data *) scsi_dh_data->buf;
h->default_sp = CLARIION_UNBOUND_LU;
h->current_sp = CLARIION_UNBOUND_LU;
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);
sdev_printk(KERN_NOTICE, sdev, "Attached %s.\n", CLARIION_NAME);
try_module_get(THIS_MODULE);
} else if (action == BUS_NOTIFY_DEL_DEVICE) {
if (sdev->scsi_dh_data == NULL ||
sdev->scsi_dh_data->scsi_dh != &clariion_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);
sdev_printk(KERN_NOTICE, sdev, "Dettached %s.\n",
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",
CLARIION_NAME);
kfree(scsi_dh_data);
module_put(THIS_MODULE);
return -ENOMEM;
}
out:
scsi_dh_data->scsi_dh = &clariion_dh;
h = (struct clariion_dh_data *) scsi_dh_data->buf;
h->default_sp = CLARIION_UNBOUND_LU;
h->current_sp = CLARIION_UNBOUND_LU;
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);
sdev_printk(KERN_NOTICE, sdev, "Attached %s.\n", CLARIION_NAME);
try_module_get(THIS_MODULE);
return 0;
}
static void clariion_bus_detach(struct scsi_device *sdev)
{
struct scsi_dh_data *scsi_dh_data;
unsigned long flags;
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);
sdev_printk(KERN_NOTICE, sdev, "Detached %s.\n",
CLARIION_NAME);
kfree(scsi_dh_data);
module_put(THIS_MODULE);
}
static int __init clariion_init(void)
{
int r;

94
drivers/scsi/device_handler/scsi_dh_hp_sw.c
View File

@ -108,87 +108,65 @@ static int hp_sw_activate(struct scsi_device *sdev)
return ret;
}
static const struct {
char *vendor;
char *model;
} hp_sw_dh_data_list[] = {
const struct scsi_dh_devlist hp_sw_dh_data_list[] = {
{"COMPAQ", "MSA"},
{"HP", "HSV"},
{"DEC", "HSG80"},
{NULL, NULL},
};
static int hp_sw_bus_notify(struct notifier_block *, unsigned long, void *);
static int hp_sw_bus_attach(struct scsi_device *sdev);
static void hp_sw_bus_detach(struct scsi_device *sdev);
static struct scsi_device_handler hp_sw_dh = {
.name = HP_SW_NAME,
.module = THIS_MODULE,
.nb.notifier_call = hp_sw_bus_notify,
.devlist = hp_sw_dh_data_list,
.attach = hp_sw_bus_attach,
.detach = hp_sw_bus_detach,
.activate = hp_sw_activate,
};
static int hp_sw_bus_notify(struct notifier_block *nb,
unsigned long action, void *data)
static int hp_sw_bus_attach(struct scsi_device *sdev)
{
struct device *dev = data;
struct scsi_device *sdev;
struct scsi_dh_data *scsi_dh_data;
int i, found = 0;
unsigned long flags;
if (!scsi_is_sdev_device(dev))
scsi_dh_data = kzalloc(sizeof(struct scsi_device_handler *)
+ sizeof(struct hp_sw_dh_data) , GFP_KERNEL);
if (!scsi_dh_data) {
sdev_printk(KERN_ERR, sdev, "Attach Failed %s.\n",
HP_SW_NAME);
return 0;
sdev = to_scsi_device(dev);
if (action == BUS_NOTIFY_ADD_DEVICE) {
for (i = 0; hp_sw_dh_data_list[i].vendor; i++) {
if (!strncmp(sdev->vendor, hp_sw_dh_data_list[i].vendor,
strlen(hp_sw_dh_data_list[i].vendor)) &&
!strncmp(sdev->model, hp_sw_dh_data_list[i].model,
strlen(hp_sw_dh_data_list[i].model))) {
found = 1;
break;
}
}
if (!found)
goto out;
scsi_dh_data = kzalloc(sizeof(struct scsi_device_handler *)
+ sizeof(struct hp_sw_dh_data) , GFP_KERNEL);
if (!scsi_dh_data) {
sdev_printk(KERN_ERR, sdev, "Attach Failed %s.\n",
HP_SW_NAME);
goto out;
}
scsi_dh_data->scsi_dh = &hp_sw_dh;
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", HP_SW_NAME);
} else if (action == BUS_NOTIFY_DEL_DEVICE) {
if (sdev->scsi_dh_data == NULL ||
sdev->scsi_dh_data->scsi_dh != &hp_sw_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);
module_put(THIS_MODULE);
sdev_printk(KERN_NOTICE, sdev, "Dettached %s.\n", HP_SW_NAME);
kfree(scsi_dh_data);
}
out:
scsi_dh_data->scsi_dh = &hp_sw_dh;
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", HP_SW_NAME);
return 0;
}
static void hp_sw_bus_detach( struct scsi_device *sdev )
{
struct scsi_dh_data *scsi_dh_data;
unsigned long flags;
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);
module_put(THIS_MODULE);
sdev_printk(KERN_NOTICE, sdev, "Detached %s\n", HP_SW_NAME);
kfree(scsi_dh_data);
}
static int __init hp_sw_init(void)
{
return scsi_register_device_handler(&hp_sw_dh);

111
drivers/scsi/device_handler/scsi_dh_rdac.c
View File

@ -569,10 +569,7 @@ static int rdac_check_sense(struct scsi_device *sdev,
return SCSI_RETURN_NOT_HANDLED;
}
static const struct {
char *vendor;
char *model;
} rdac_dev_list[] = {
const struct scsi_dh_devlist rdac_dev_list[] = {
{"IBM", "1722"},
{"IBM", "1724"},
{"IBM", "1726"},
@ -590,89 +587,69 @@ static const struct {
{NULL, NULL},
};
static int rdac_bus_notify(struct notifier_block *, unsigned long, void *);
static int rdac_bus_attach(struct scsi_device *sdev);
static void rdac_bus_detach(struct scsi_device *sdev);
static struct scsi_device_handler rdac_dh = {
.name = RDAC_NAME,
.module = THIS_MODULE,
.nb.notifier_call = rdac_bus_notify,
.devlist = rdac_dev_list,
.prep_fn = rdac_prep_fn,
.check_sense = rdac_check_sense,
.attach = rdac_bus_attach,
.detach = rdac_bus_detach,
.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)
static int rdac_bus_attach(struct scsi_device *sdev)
{
struct device *dev = data;
struct scsi_device *sdev;
struct scsi_dh_data *scsi_dh_data;
struct rdac_dh_data *h;
int i, found = 0;
unsigned long flags;
if (!scsi_is_sdev_device(dev))
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);
return 0;
sdev = to_scsi_device(dev);
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:
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);
return 0;
}
static void rdac_bus_detach( struct scsi_device *sdev )
{
struct scsi_dh_data *scsi_dh_data;
struct rdac_dh_data *h;
unsigned long flags;
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, "Detached %s\n", RDAC_NAME);
}
static int __init rdac_init(void)
{
int r;

9
include/scsi/scsi_device.h
View File

@ -167,15 +167,22 @@ struct scsi_device {
unsigned long sdev_data[0];
} __attribute__((aligned(sizeof(unsigned long))));
struct scsi_dh_devlist {
char *vendor;
char *model;
};
struct scsi_device_handler {
/* Used by the infrastructure */
struct list_head list; /* list of scsi_device_handlers */
struct notifier_block nb;
/* Filled by the hardware handler */
struct module *module;
const char *name;
const struct scsi_dh_devlist *devlist;
int (*check_sense)(struct scsi_device *, struct scsi_sense_hdr *);
int (*attach)(struct scsi_device *);
void (*detach)(struct scsi_device *);
int (*activate)(struct scsi_device *);
int (*prep_fn)(struct scsi_device *, struct request *);
};