This patch (as1249c) adds an extra state, STARGET_NEW, to the SCSI
target state model. A target is in this state initially and changes
over to STARGET_CREATED when the hostt->target_alloc() call has been
made.
This simplifies target destruction. There's no need for a separate
scsi_target_destroy() function; everything can be handled within
scsi_target_reap(). The error paths are more robust because now it's
easy to verify that all the destructors are called along every
pathway.
Signed-off-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
---
The revision gets rid of an unnecessary spin_lock/spin_unlock pair
surrounding the line where starget->state is changed from STARGET_NEW
to STARGET_CREATED.
Index: usb-2.6/include/scsi/scsi_device.h
===================================================================
--- usb-2.6.orig/include/scsi/scsi_device.h
+++ usb-2.6/include/scsi/scsi_device.h
@@ -211,7 +211,8 @@ struct scsi_dh_data {
sdev_printk(prefix, (scmd)->device, fmt, ##a)
enum scsi_target_state {
- STARGET_CREATED = 1,
+ STARGET_NEW = 1,
+ STARGET_CREATED,
STARGET_RUNNING,
STARGET_DEL,
};
Index: usb-2.6/drivers/scsi/scsi_scan.c
===================================================================
--- usb-2.6.orig/drivers/scsi/scsi_scan.c
+++ usb-2.6/drivers/scsi/scsi_scan.c
@@ -324,21 +324,6 @@ out:
return NULL;
}
-static void scsi_target_destroy(struct scsi_target *starget)
-{
- struct device *dev = &starget->dev;
- struct Scsi_Host *shost = dev_to_shost(dev->parent);
- unsigned long flags;
-
- transport_destroy_device(dev);
- spin_lock_irqsave(shost->host_lock, flags);
- if (shost->hostt->target_destroy)
- shost->hostt->target_destroy(starget);
- list_del_init(&starget->siblings);
- spin_unlock_irqrestore(shost->host_lock, flags);
- put_device(dev);
-}
-
static void scsi_target_dev_release(struct device *dev)
{
struct device *parent = dev->parent;
@@ -423,7 +408,7 @@ static struct scsi_target *scsi_alloc_ta
starget->can_queue = 0;
INIT_LIST_HEAD(&starget->siblings);
INIT_LIST_HEAD(&starget->devices);
- starget->state = STARGET_CREATED;
+ starget->state = STARGET_NEW;
starget->scsi_level = SCSI_2;
starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED;
retry:
@@ -439,15 +424,14 @@ static struct scsi_target *scsi_alloc_ta
transport_setup_device(dev);
if (shost->hostt->target_alloc) {
error = shost->hostt->target_alloc(starget);
-
- if(error) {
- dev_printk(KERN_ERR, dev, "target allocation failed, error %d\n", error);
- /* don't want scsi_target_reap to do the final
- * put because it will be under the host lock */
- scsi_target_destroy(starget);
+ if (error) {
+ dev_printk(KERN_ERR, dev,
+ "target allocation failed, error %d\n", error);
+ scsi_target_reap(starget);
return NULL;
}
}
+ starget->state = STARGET_CREATED;
get_device(dev);
return starget;
@@ -456,8 +440,7 @@ static struct scsi_target *scsi_alloc_ta
found_target->reap_ref++;
spin_unlock_irqrestore(shost->host_lock, flags);
if (found_target->state != STARGET_DEL) {
- put_device(parent);
- kfree(starget);
+ scsi_target_reap(starget);
return found_target;
}
/* Unfortunately, we found a dying target; need to
@@ -477,7 +460,8 @@ static struct scsi_target *scsi_alloc_ta
*/
void scsi_target_reap(struct scsi_target *starget)
{
- struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
+ struct device *dev = &starget->dev;
+ struct Scsi_Host *shost = dev_to_shost(dev->parent);
unsigned long flags;
enum scsi_target_state state;
int empty;
@@ -493,10 +477,17 @@ void scsi_target_reap(struct scsi_target
BUG_ON(state == STARGET_DEL || !list_empty(&starget->devices));
starget->state = STARGET_DEL;
if (state == STARGET_RUNNING) {
- transport_remove_device(&starget->dev);
- device_del(&starget->dev);
+ transport_remove_device(dev);
+ device_del(dev);
}
- scsi_target_destroy(starget);
+
+ transport_destroy_device(dev);
+ spin_lock_irqsave(shost->host_lock, flags);
+ if (state != STARGET_NEW && shost->hostt->target_destroy)
+ shost->hostt->target_destroy(starget);
+ list_del_init(&starget->siblings);
+ spin_unlock_irqrestore(shost->host_lock, flags);
+ put_device(dev);
}
/**
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
