[PATCH] get rid of struct file use in blkdev_ioctl() BLKBSZSET

We need to do bd_claim() only if file hadn't been opened with O_EXCL
and then we have no need to use file itself as owner.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

block/ioctl.c

@@ -343,10 +343,11 @@ int blkdev_ioctl(struct inode *inode, struct file *file, unsigned cmd,
 			return -EINVAL;
 		if (get_user(n, (int __user *) arg))
 			return -EFAULT;
-		if (bd_claim(bdev, file) < 0)
+		if (!(mode & FMODE_EXCL) && bd_claim(bdev, &bdev) < 0)
 			return -EBUSY;
 		ret = set_blocksize(bdev, n);
-		bd_release(bdev);
+		if (!(mode & FMODE_EXCL))
+			bd_release(bdev);
 		return ret;
 	case BLKPG:
 		lock_kernel();