diff options
author | Arnd Bergmann <arnd@arndb.de> | 2010-07-21 10:36:39 +0400 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2010-07-21 10:36:39 +0400 |
commit | a3108ca2323dec0f6321c3f7706cdaed51f694ea (patch) | |
tree | ae3ef899219893cf3de5d543d4e3dc7027c00212 /drivers/sbus/char/flash.c | |
parent | f8324e20f8289dffc646d64366332e05eaacab25 (diff) | |
download | linux-a3108ca2323dec0f6321c3f7706cdaed51f694ea.tar.xz |
sbus: 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.
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>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/sbus/char/flash.c')
-rw-r--r-- | drivers/sbus/char/flash.c | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/drivers/sbus/char/flash.c b/drivers/sbus/char/flash.c index 368d66294d83..ed9494e18859 100644 --- a/drivers/sbus/char/flash.c +++ b/drivers/sbus/char/flash.c @@ -10,7 +10,7 @@ #include <linux/fcntl.h> #include <linux/poll.h> #include <linux/init.h> -#include <linux/smp_lock.h> +#include <linux/mutex.h> #include <linux/spinlock.h> #include <linux/mm.h> #include <linux/of.h> @@ -22,6 +22,7 @@ #include <asm/io.h> #include <asm/upa.h> +static DEFINE_MUTEX(flash_mutex); static DEFINE_SPINLOCK(flash_lock); static struct { unsigned long read_base; /* Physical read address */ @@ -80,7 +81,7 @@ flash_mmap(struct file *file, struct vm_area_struct *vma) static long long flash_llseek(struct file *file, long long offset, int origin) { - lock_kernel(); + mutex_lock(&flash_mutex); switch (origin) { case 0: file->f_pos = offset; @@ -94,10 +95,10 @@ flash_llseek(struct file *file, long long offset, int origin) file->f_pos = flash.read_size; break; default: - unlock_kernel(); + mutex_unlock(&flash_mutex); return -EINVAL; } - unlock_kernel(); + mutex_unlock(&flash_mutex); return file->f_pos; } @@ -125,13 +126,13 @@ flash_read(struct file * file, char __user * buf, static int flash_open(struct inode *inode, struct file *file) { - lock_kernel(); + mutex_lock(&flash_mutex); if (test_and_set_bit(0, (void *)&flash.busy) != 0) { - unlock_kernel(); + mutex_unlock(&flash_mutex); return -EBUSY; } - unlock_kernel(); + mutex_unlock(&flash_mutex); return 0; } |