path: root/drivers/char/toshiba.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/char/toshiba.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/char/toshiba.c')
1 files changed, 5 insertions, 4 deletions
diff --git a/drivers/char/toshiba.c b/drivers/char/toshiba.c
index f8bc79f6de34..f8f09ab0b170 100644
--- a/drivers/char/toshiba.c
+++ b/drivers/char/toshiba.c
@@ -68,7 +68,7 @@
#include <linux/stat.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
-#include <linux/smp_lock.h>
+#include <linux/mutex.h>
#include <linux/toshiba.h>
#define TOSH_MINOR_DEV 181
@@ -78,6 +78,7 @@ MODULE_AUTHOR("Jonathan Buzzard <jonathan@buzzard.org.uk>");
MODULE_DESCRIPTION("Toshiba laptop SMM driver");
+static DEFINE_MUTEX(tosh_mutex);
static int tosh_fn;
module_param_named(fn, tosh_fn, int, 0);
MODULE_PARM_DESC(fn, "User specified Fn key detection port");
@@ -274,16 +275,16 @@ static long tosh_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
return -EINVAL;
/* do we need to emulate the fan ? */
- lock_kernel();
+ mutex_lock(&tosh_mutex);
if (tosh_fan==1) {
if (((ax==0xf300) || (ax==0xf400)) && (bx==0x0004)) {
err = tosh_emulate_fan(&regs);
- unlock_kernel();
+ mutex_unlock(&tosh_mutex);
err = tosh_smm(&regs);
- unlock_kernel();
+ mutex_unlock(&tosh_mutex);
return -EINVAL;