dvb/bt8xx: kill the big kernel lock

The bt8xx driver only uses the big kernel lock in its dst_ca_ioctl
function and never to serialize against other code, so we can
trivially replace it with a private mutex.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: linux-media@vger.kernel.org
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
This commit is contained in:
Arnd Bergmann 2010-09-11 19:53:25 +02:00
Родитель efbec1cd04
Коммит adfedd216d
1 изменённых файлов: 4 добавлений и 3 удалений

Просмотреть файл

@ -22,7 +22,7 @@
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/smp_lock.h>
#include <linux/mutex.h>
#include <linux/string.h>
#include <linux/dvb/ca.h>
#include "dvbdev.h"
@ -52,6 +52,7 @@
} while(0)
static DEFINE_MUTEX(dst_ca_mutex);
static unsigned int verbose = 5;
module_param(verbose, int, 0644);
MODULE_PARM_DESC(verbose, "verbose startup messages, default is 1 (yes)");
@ -564,7 +565,7 @@ static long dst_ca_ioctl(struct file *file, unsigned int cmd, unsigned long ioct
void __user *arg = (void __user *)ioctl_arg;
int result = 0;
lock_kernel();
mutex_lock(&dst_ca_mutex);
dvbdev = file->private_data;
state = (struct dst_state *)dvbdev->priv;
p_ca_message = kmalloc(sizeof (struct ca_msg), GFP_KERNEL);
@ -652,7 +653,7 @@ static long dst_ca_ioctl(struct file *file, unsigned int cmd, unsigned long ioct
kfree (p_ca_slot_info);
kfree (p_ca_caps);
unlock_kernel();
mutex_unlock(&dst_ca_mutex);
return result;
}