diff options
author | Arnd Bergmann <arnd@arndb.de> | 2010-06-02 14:28:52 +0200 |
---|---|---|
committer | Arnd Bergmann <arnd@arndb.de> | 2010-10-05 15:01:04 +0200 |
commit | 613655fa39ff6957754fa8ceb8559980920eb8ee (patch) | |
tree | ad19600cb81207b24188683d7fc4ae88013339d1 /drivers/char/nwflash.c | |
parent | 609146fdb319cebce93be550938ab852f7bade90 (diff) | |
download | lwn-613655fa39ff6957754fa8ceb8559980920eb8ee.tar.gz lwn-613655fa39ff6957754fa8ceb8559980920eb8ee.zip |
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/nwflash.c')
-rw-r--r-- | drivers/char/nwflash.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/drivers/char/nwflash.c b/drivers/char/nwflash.c index 043a1c7b86be..a12f52400dbc 100644 --- a/drivers/char/nwflash.c +++ b/drivers/char/nwflash.c @@ -25,7 +25,6 @@ #include <linux/spinlock.h> #include <linux/rwsem.h> #include <linux/init.h> -#include <linux/smp_lock.h> #include <linux/mutex.h> #include <linux/jiffies.h> @@ -41,6 +40,7 @@ #define NWFLASH_VERSION "6.4" +static DEFINE_MUTEX(flash_mutex); static void kick_open(void); static int get_flash_id(void); static int erase_block(int nBlock); @@ -96,7 +96,7 @@ static int get_flash_id(void) static long flash_ioctl(struct file *filep, unsigned int cmd, unsigned long arg) { - lock_kernel(); + mutex_lock(&flash_mutex); switch (cmd) { case CMD_WRITE_DISABLE: gbWriteBase64Enable = 0; @@ -114,10 +114,10 @@ static long flash_ioctl(struct file *filep, unsigned int cmd, unsigned long arg) default: gbWriteBase64Enable = 0; gbWriteEnable = 0; - unlock_kernel(); + mutex_unlock(&flash_mutex); return -EINVAL; } - unlock_kernel(); + mutex_unlock(&flash_mutex); return 0; } @@ -282,7 +282,7 @@ static loff_t flash_llseek(struct file *file, loff_t offset, int orig) { loff_t ret; - lock_kernel(); + mutex_lock(&flash_mutex); if (flashdebug) printk(KERN_DEBUG "flash_llseek: offset=0x%X, orig=0x%X.\n", (unsigned int) offset, orig); @@ -317,7 +317,7 @@ static loff_t flash_llseek(struct file *file, loff_t offset, int orig) default: ret = -EINVAL; } - unlock_kernel(); + mutex_unlock(&flash_mutex); return ret; } |