path: root/drivers/rtc/rtc-m41t80.c
diff options
authorArnd Bergmann <arnd@arndb.de>2010-06-02 14:28:52 +0200
committerArnd Bergmann <arnd@arndb.de>2010-10-05 15:01:04 +0200
commit613655fa39ff6957754fa8ceb8559980920eb8ee (patch)
treead19600cb81207b24188683d7fc4ae88013339d1 /drivers/rtc/rtc-m41t80.c
parentipmi: autoconvert trivial BKL users to private mutex (diff)
drivers: autoconvert trivial BKL users to private mutex
All these files use the big kernel lock in a trivial way to serialize their private file operations, typically resulting from an earlier semi-automatic pushdown from VFS. None of these drivers appears to want to lock against other code, and they all use the BKL as the top-level lock in their file operations, meaning that there is no lock-order inversion problem. Consequently, we can remove the BKL completely, replacing it with a per-file mutex in every case. Using a scripted approach means we can avoid typos. These drivers do not seem to be under active maintainance from my brief investigation. Apologies to those maintainers that I have missed. file=$1 name=$2 if grep -q lock_kernel ${file} ; then if grep -q 'include.*linux.mutex.h' ${file} ; then sed -i '/include.*<linux\/smp_lock.h>/d' ${file} else sed -i 's/include.*<linux\/smp_lock.h>.*$/include <linux\/mutex.h>/g' ${file} fi sed -i ${file} \ -e "/^#include.*linux.mutex.h/,$ { 1,/^\(static\|int\|long\)/ { /^\(static\|int\|long\)/istatic DEFINE_MUTEX(${name}_mutex); } }" \ -e "s/\(un\)*lock_kernel\>[ ]*()/mutex_\1lock(\&${name}_mutex)/g" \ -e '/[ ]*cycle_kernel_lock();/d' else sed -i -e '/include.*\<smp_lock.h\>/d' ${file} \ -e '/cycle_kernel_lock()/d' fi Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'drivers/rtc/rtc-m41t80.c')
1 files changed, 7 insertions, 6 deletions
diff --git a/drivers/rtc/rtc-m41t80.c b/drivers/rtc/rtc-m41t80.c
index d60557cae8ef..512dca16a42c 100644
--- a/drivers/rtc/rtc-m41t80.c
+++ b/drivers/rtc/rtc-m41t80.c
@@ -20,7 +20,7 @@
#include <linux/module.h>
#include <linux/rtc.h>
#include <linux/slab.h>
-#include <linux/smp_lock.h>
+#include <linux/mutex.h>
#include <linux/string.h>
#include <linux/fs.h>
@@ -68,6 +68,7 @@
#define DRV_VERSION "0.05"
+static DEFINE_MUTEX(m41t80_rtc_mutex);
static const struct i2c_device_id m41t80_id[] = {
{ "m41t62", M41T80_FEATURE_SQ | M41T80_FEATURE_SQ_ALT },
{ "m41t65", M41T80_FEATURE_HT | M41T80_FEATURE_WD },
@@ -677,9 +678,9 @@ static long wdt_unlocked_ioctl(struct file *file, unsigned int cmd,
int ret;
- lock_kernel();
+ mutex_lock(&m41t80_rtc_mutex);
ret = wdt_ioctl(file, cmd, arg);
- unlock_kernel();
+ mutex_unlock(&m41t80_rtc_mutex);
return ret;
@@ -693,16 +694,16 @@ static long wdt_unlocked_ioctl(struct file *file, unsigned int cmd,
static int wdt_open(struct inode *inode, struct file *file)
if (MINOR(inode->i_rdev) == WATCHDOG_MINOR) {
- lock_kernel();
+ mutex_lock(&m41t80_rtc_mutex);
if (test_and_set_bit(0, &wdt_is_open)) {
- unlock_kernel();
+ mutex_unlock(&m41t80_rtc_mutex);
return -EBUSY;
* Activate
wdt_is_open = 1;
- unlock_kernel();
+ mutex_unlock(&m41t80_rtc_mutex);
return nonseekable_open(inode, file);
return -ENODEV;