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path: root/drivers/scsi/device_handler/scsi_dh.c
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Diffstat (limited to 'drivers/scsi/device_handler/scsi_dh.c')
-rw-r--r--drivers/scsi/device_handler/scsi_dh.c55
1 files changed, 41 insertions, 14 deletions
diff --git a/drivers/scsi/device_handler/scsi_dh.c b/drivers/scsi/device_handler/scsi_dh.c
index 33e422e75835..1dba62c5cf6a 100644
--- a/drivers/scsi/device_handler/scsi_dh.c
+++ b/drivers/scsi/device_handler/scsi_dh.c
@@ -98,27 +98,51 @@ device_handler_match(struct scsi_device_handler *scsi_dh,
static int scsi_dh_handler_attach(struct scsi_device *sdev,
struct scsi_device_handler *scsi_dh)
{
- int err = 0;
+ struct scsi_dh_data *d;
if (sdev->scsi_dh_data) {
if (sdev->scsi_dh_data->scsi_dh != scsi_dh)
- err = -EBUSY;
- else
- kref_get(&sdev->scsi_dh_data->kref);
- } else if (scsi_dh->attach) {
- err = scsi_dh->attach(sdev);
- if (!err) {
- kref_init(&sdev->scsi_dh_data->kref);
- sdev->scsi_dh_data->sdev = sdev;
- }
+ return -EBUSY;
+
+ kref_get(&sdev->scsi_dh_data->kref);
+ return 0;
}
- return err;
+
+ if (!try_module_get(scsi_dh->module))
+ return -EINVAL;
+
+ d = scsi_dh->attach(sdev);
+ if (IS_ERR(d)) {
+ sdev_printk(KERN_ERR, sdev, "%s: Attach failed (%ld)\n",
+ scsi_dh->name, PTR_ERR(d));
+ module_put(scsi_dh->module);
+ return PTR_ERR(d);
+ }
+
+ d->scsi_dh = scsi_dh;
+ kref_init(&d->kref);
+ d->sdev = sdev;
+
+ spin_lock_irq(sdev->request_queue->queue_lock);
+ sdev->scsi_dh_data = d;
+ spin_unlock_irq(sdev->request_queue->queue_lock);
+ return 0;
}
static void __detach_handler (struct kref *kref)
{
- struct scsi_dh_data *scsi_dh_data = container_of(kref, struct scsi_dh_data, kref);
- scsi_dh_data->scsi_dh->detach(scsi_dh_data->sdev);
+ struct scsi_dh_data *scsi_dh_data =
+ container_of(kref, struct scsi_dh_data, kref);
+ struct scsi_device_handler *scsi_dh = scsi_dh_data->scsi_dh;
+ struct scsi_device *sdev = scsi_dh_data->sdev;
+
+ spin_lock_irq(sdev->request_queue->queue_lock);
+ sdev->scsi_dh_data = NULL;
+ spin_unlock_irq(sdev->request_queue->queue_lock);
+
+ scsi_dh->detach(sdev);
+ sdev_printk(KERN_NOTICE, sdev, "%s: Detached\n", scsi_dh->name);
+ module_put(scsi_dh->module);
}
/*
@@ -141,7 +165,7 @@ static void scsi_dh_handler_detach(struct scsi_device *sdev,
if (!scsi_dh)
scsi_dh = sdev->scsi_dh_data->scsi_dh;
- if (scsi_dh && scsi_dh->detach)
+ if (scsi_dh)
kref_put(&sdev->scsi_dh_data->kref, __detach_handler);
}
@@ -330,6 +354,9 @@ int scsi_register_device_handler(struct scsi_device_handler *scsi_dh)
if (get_device_handler(scsi_dh->name))
return -EBUSY;
+ if (!scsi_dh->attach || !scsi_dh->detach)
+ return -EINVAL;
+
spin_lock(&list_lock);
list_add(&scsi_dh->list, &scsi_dh_list);
spin_unlock(&list_lock);