[patch 4/7] sh: Remove BKL from landisk gio

From: Thomas Gleixner
Date: Thu Oct 15 2009 - 04:43:51 EST


The open function got the BKL via the big push down. Replace it by
preempt_enable/disable as this is sufficient for an UP machine.

The ioctl can be unlocked because there is no functionality which
requires serialization. The usage by multiple callers is broken with
and without the BKL due to the local static variable addr.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Paul Mundt <lethal@xxxxxxxxxxxx>
---
arch/sh/boards/mach-landisk/gio.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)

Index: linux-2.6-tip/arch/sh/boards/mach-landisk/gio.c
===================================================================
--- linux-2.6-tip.orig/arch/sh/boards/mach-landisk/gio.c
+++ linux-2.6-tip/arch/sh/boards/mach-landisk/gio.c
@@ -14,7 +14,6 @@
*/
#include <linux/module.h>
#include <linux/init.h>
-#include <linux/smp_lock.h>
#include <linux/kdev_t.h>
#include <linux/cdev.h>
#include <linux/fs.h>
@@ -35,7 +34,7 @@ static int gio_open(struct inode *inode,
int minor;
int ret = -ENOENT;

- lock_kernel();
+ preempt_disable();
minor = MINOR(inode->i_rdev);
if (minor < DEVCOUNT) {
if (openCnt > 0) {
@@ -45,7 +44,7 @@ static int gio_open(struct inode *inode,
ret = 0;
}
}
- unlock_kernel();
+ preempt_enable();
return ret;
}

@@ -60,8 +59,7 @@ static int gio_close(struct inode *inode
return 0;
}

-static int gio_ioctl(struct inode *inode, struct file *filp,
- unsigned int cmd, unsigned long arg)
+static long gio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
unsigned int data;
static unsigned int addr = 0;
@@ -129,7 +127,7 @@ static const struct file_operations gio_
.owner = THIS_MODULE,
.open = gio_open, /* open */
.release = gio_close, /* release */
- .ioctl = gio_ioctl, /* ioctl */
+ .unlocked_ioctl = gio_ioctl,
};

static int __init gio_init(void)


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/