USB: BKL removal from ioctl path of usbfs

Total removal from the ioctl code path except for the outcall
to external modules. Locking is ensured by the normal locks
of usbfs.

Signed-off-by: Oliver Neukum <oliver@neukum.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/core/devio.c

@@ -1636,7 +1636,10 @@ static int proc_ioctl(struct dev_state *ps, struct usbdevfs_ioctl *ctl)
 		if (driver == NULL || driver->ioctl == NULL) {
 			retval = -ENOTTY;
 		} else {
+			/* keep API that guarantees BKL */
+			lock_kernel();
 			retval = driver->ioctl(intf, ctl->ioctl_code, buf);
+			unlock_kernel();
 			if (retval == -ENOIOCTLCMD)
 				retval = -ENOTTY;
 		}
@@ -1720,11 +1723,9 @@ static long usbdev_do_ioctl(struct file *file, unsigned int cmd,
 	if (!(file->f_mode & FMODE_WRITE))
 		return -EPERM;
 
-	lock_kernel();
 	usb_lock_device(dev);
 	if (!connected(ps)) {
 		usb_unlock_device(dev);
-		unlock_kernel();
 		return -ENODEV;
 	}
 
@@ -1783,12 +1784,10 @@ static long usbdev_do_ioctl(struct file *file, unsigned int cmd,
 		break;
 
 	case USBDEVFS_SUBMITURB:
-		unlock_kernel();
 		snoop(&dev->dev, "%s: SUBMITURB\n", __func__);
 		ret = proc_submiturb(ps, p);
 		if (ret >= 0)
 			inode->i_mtime = CURRENT_TIME;
-		lock_kernel();
 		break;
 
 #ifdef CONFIG_COMPAT
@@ -1840,17 +1839,13 @@ static long usbdev_do_ioctl(struct file *file, unsigned int cmd,
 		break;
 
 	case USBDEVFS_REAPURB:
-		unlock_kernel();
 		snoop(&dev->dev, "%s: REAPURB\n", __func__);
 		ret = proc_reapurb(ps, p);
-		lock_kernel();
 		break;
 
 	case USBDEVFS_REAPURBNDELAY:
-		unlock_kernel();
 		snoop(&dev->dev, "%s: REAPURBNDELAY\n", __func__);
 		ret = proc_reapurbnonblock(ps, p);
-		lock_kernel();
 		break;
 
 	case USBDEVFS_DISCSIGNAL:
@@ -1884,7 +1879,6 @@ static long usbdev_do_ioctl(struct file *file, unsigned int cmd,
 		break;
 	}
 	usb_unlock_device(dev);
-	unlock_kernel();
 	if (ret >= 0)
 		inode->i_atime = CURRENT_TIME;
 	return ret;