USB: drivers/block/ub.c: use list_for_each_entry()

Low performance USB storage driver: Use list_for_each_entry() instead
of list_for_each()

Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/block/ub.c

@@ -1547,10 +1547,8 @@ static void ub_reset_enter(struct ub_dev *sc, int try)
 #endif
 
 #if 0 /* We let them stop themselves. */
-	struct list_head *p;
 	struct ub_lun *lun;
-	list_for_each(p, &sc->luns) {
-		lun = list_entry(p, struct ub_lun, link);
+	list_for_each_entry(lun, &sc->luns, link) {
 		blk_stop_queue(lun->disk->queue);
 	}
 #endif
@@ -1562,7 +1560,6 @@ static void ub_reset_task(struct work_struct *work)
 {
 	struct ub_dev *sc = container_of(work, struct ub_dev, reset_work);
 	unsigned long flags;
-	struct list_head *p;
 	struct ub_lun *lun;
 	int lkr, rc;
 
@@ -1608,8 +1605,7 @@ static void ub_reset_task(struct work_struct *work)
 	spin_lock_irqsave(sc->lock, flags);
 	sc->reset = 0;
 	tasklet_schedule(&sc->tasklet);
-	list_for_each(p, &sc->luns) {
-		lun = list_entry(p, struct ub_lun, link);
+	list_for_each_entry(lun, &sc->luns, link) {
 		blk_start_queue(lun->disk->queue);
 	}
 	wake_up(&sc->reset_wait);
@@ -2348,7 +2344,6 @@ err_alloc:
 static void ub_disconnect(struct usb_interface *intf)
 {
 	struct ub_dev *sc = usb_get_intfdata(intf);
-	struct list_head *p;
 	struct ub_lun *lun;
 	unsigned long flags;
 
@@ -2403,8 +2398,7 @@ static void ub_disconnect(struct usb_interface *intf)
 	/*
 	 * Unregister the upper layer.
 	 */
-	list_for_each (p, &sc->luns) {
-		lun = list_entry(p, struct ub_lun, link);
+	list_for_each_entry(lun, &sc->luns, link) {
 		del_gendisk(lun->disk);
 		/*
 		 * I wish I could do: