block: autoconvert trivial BKL users to private mutex
The block device drivers have all gained new lock_kernel
calls from a recent pushdown, and some of the drivers
were already using the BKL before.
This turns the BKL into a set of per-driver mutexes.
Still need to check whether this is safe to do.
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>
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 91797bb..a10c8c9 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -67,7 +67,7 @@
#include <linux/compat.h>
#include <linux/suspend.h>
#include <linux/freezer.h>
-#include <linux/smp_lock.h>
+#include <linux/mutex.h>
#include <linux/writeback.h>
#include <linux/buffer_head.h> /* for invalidate_bdev() */
#include <linux/completion.h>
@@ -77,6 +77,7 @@
#include <asm/uaccess.h>
+static DEFINE_MUTEX(loop_mutex);
static LIST_HEAD(loop_devices);
static DEFINE_MUTEX(loop_devices_mutex);
@@ -1409,11 +1410,11 @@
{
struct loop_device *lo = bdev->bd_disk->private_data;
- lock_kernel();
+ mutex_lock(&loop_mutex);
mutex_lock(&lo->lo_ctl_mutex);
lo->lo_refcnt++;
mutex_unlock(&lo->lo_ctl_mutex);
- unlock_kernel();
+ mutex_unlock(&loop_mutex);
return 0;
}
@@ -1423,7 +1424,7 @@
struct loop_device *lo = disk->private_data;
int err;
- lock_kernel();
+ mutex_lock(&loop_mutex);
mutex_lock(&lo->lo_ctl_mutex);
if (--lo->lo_refcnt)
@@ -1448,7 +1449,7 @@
out:
mutex_unlock(&lo->lo_ctl_mutex);
out_unlocked:
- lock_kernel();
+ mutex_unlock(&loop_mutex);
return 0;
}