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authorArnd Bergmann <arnd@arndb.de>2010-06-02 16:28:52 +0400
committerArnd Bergmann <arnd@arndb.de>2010-10-05 17:01:04 +0400
commit613655fa39ff6957754fa8ceb8559980920eb8ee (patch)
treead19600cb81207b24188683d7fc4ae88013339d1 /drivers/char/i8k.c
parent609146fdb319cebce93be550938ab852f7bade90 (diff)
downloadlinux-613655fa39ff6957754fa8ceb8559980920eb8ee.tar.xz
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/i8k.c')
-rw-r--r--drivers/char/i8k.c7
1 files changed, 4 insertions, 3 deletions
diff --git a/drivers/char/i8k.c b/drivers/char/i8k.c
index 4cd8b227c11f..3bc0eef88717 100644
--- a/drivers/char/i8k.c
+++ b/drivers/char/i8k.c
@@ -23,7 +23,7 @@
#include <linux/seq_file.h>
#include <linux/dmi.h>
#include <linux/capability.h>
-#include <linux/smp_lock.h>
+#include <linux/mutex.h>
#include <asm/uaccess.h>
#include <asm/io.h>
@@ -56,6 +56,7 @@
#define I8K_TEMPERATURE_BUG 1
+static DEFINE_MUTEX(i8k_mutex);
static char bios_version[4];
MODULE_AUTHOR("Massimo Dal Zotto (dz@debian.org)");
@@ -399,9 +400,9 @@ static long i8k_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
{
long ret;
- lock_kernel();
+ mutex_lock(&i8k_mutex);
ret = i8k_ioctl_unlocked(fp, cmd, arg);
- unlock_kernel();
+ mutex_unlock(&i8k_mutex);
return ret;
}