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/pcmcia/cm4000_cs.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'drivers/char/pcmcia/cm4000_cs.c') diff --git a/drivers/char/pcmcia/cm4000_cs.c b/drivers/char/pcmcia/cm4000_cs.c index ec73d9f6d9ed..7d091b68d247 100644 --- a/drivers/char/pcmcia/cm4000_cs.c +++ b/drivers/char/pcmcia/cm4000_cs.c @@ -30,7 +30,7 @@ #include #include #include -#include +#include #include #include @@ -55,6 +55,7 @@ __func__ , ## args); \ } while (0) +static DEFINE_MUTEX(cmm_mutex); static char *version = "cm4000_cs.c v2.4.0gm6 - All bugs added by Harald Welte"; #define T_1SEC (HZ) @@ -1418,7 +1419,7 @@ static long cmm_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) iminor(inode), ioctl_names[_IOC_NR(cmd)]); #endif - lock_kernel(); + mutex_lock(&cmm_mutex); rc = -ENODEV; link = dev_table[iminor(inode)]; if (!pcmcia_dev_present(link)) { @@ -1626,7 +1627,7 @@ static long cmm_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) rc = -ENOTTY; } out: - unlock_kernel(); + mutex_unlock(&cmm_mutex); return rc; } @@ -1640,7 +1641,7 @@ static int cmm_open(struct inode *inode, struct file *filp) if (minor >= CM4000_MAX_DEV) return -ENODEV; - lock_kernel(); + mutex_lock(&cmm_mutex); link = dev_table[minor]; if (link == NULL || !pcmcia_dev_present(link)) { ret = -ENODEV; @@ -1685,7 +1686,7 @@ static int cmm_open(struct inode *inode, struct file *filp) DEBUGP(2, dev, "<- cmm_open\n"); ret = nonseekable_open(inode, filp); out: - unlock_kernel(); + mutex_unlock(&cmm_mutex); return ret; } -- cgit v1.2.3-59-g8ed1b