From 613655fa39ff6957754fa8ceb8559980920eb8ee Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Wed, 2 Jun 2010 14:28:52 +0200 Subject: 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.*/d' ${file} else sed -i 's/include.*.*$/include /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.*\/d' ${file} \ -e '/cycle_kernel_lock()/d' fi Signed-off-by: Arnd Bergmann --- drivers/char/nwflash.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'drivers/char/nwflash.c') 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 #include #include -#include #include #include @@ -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; } -- cgit v1.2.1