From 402ab352c2c00ba8f90c724565f8cf31210d99cf Mon Sep 17 00:00:00 2001
From: Arnd Bergmann <arnd@relay.de.ibm.com>
Date: Thu, 12 Aug 2010 04:13:57 +0100
Subject: [PATCH] dm ioctl: use nonseekable_open

The dm control device does not implement read/write, so it has no use for
seeking.  Using no_llseek prevents falling back to default_llseek, which
requires the BKL.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
---
 drivers/md/dm-ioctl.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index feb64d65fbfb..3fd8f0e169e7 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -1602,6 +1602,7 @@ static long dm_compat_ctl_ioctl(struct file *file, uint command, ulong u)
 #endif
 
 static const struct file_operations _ctl_fops = {
+	.open = nonseekable_open,
 	.unlocked_ioctl	 = dm_ctl_ioctl,
 	.compat_ioctl = dm_compat_ctl_ioctl,
 	.owner	 = THIS_MODULE,
-- 
2.20.1