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>

1 files changed, 7 insertions, 7 deletions

diff --git a/drivers/mtd/mtd_blkdevs.c b/drivers/mtd/mtd_blkdevs.c
index 62e68707b07..50ab431b24e 100644
--- a/drivers/mtd/mtd_blkdevs.c
+++ b/drivers/mtd/mtd_blkdevs.c
@@ -29,7 +29,6 @@
 #include <linux/blkdev.h>
 #include <linux/blkpg.h>
 #include <linux/spinlock.h>
-#include <linux/smp_lock.h>
 #include <linux/hdreg.h>
 #include <linux/init.h>
 #include <linux/mutex.h>
@@ -38,6 +37,7 @@
 
 #include "mtdcore.h"
 
+static DEFINE_MUTEX(mtd_blkdevs_mutex);
 static LIST_HEAD(blktrans_majors);
 static DEFINE_MUTEX(blktrans_ref_mutex);
 
@@ -181,7 +181,7 @@ static int blktrans_open(struct block_device *bdev, fmode_t mode)
 	if (!dev)
 		return -ERESTARTSYS; /* FIXME: busy loop! -arnd*/
 
-	lock_kernel();
+	mutex_lock(&mtd_blkdevs_mutex);
 	mutex_lock(&dev->lock);
 
 	if (!dev->mtd) {
@@ -198,7 +198,7 @@ static int blktrans_open(struct block_device *bdev, fmode_t mode)
 unlock:
 	mutex_unlock(&dev->lock);
 	blktrans_dev_put(dev);
-	unlock_kernel();
+	mutex_unlock(&mtd_blkdevs_mutex);
 	return ret;
 }
 
@@ -210,7 +210,7 @@ static int blktrans_release(struct gendisk *disk, fmode_t mode)
 	if (!dev)
 		return ret;
 
-	lock_kernel();
+	mutex_lock(&mtd_blkdevs_mutex);
 	mutex_lock(&dev->lock);
 
 	/* Release one reference, we sure its not the last one here*/
@@ -223,7 +223,7 @@ static int blktrans_release(struct gendisk *disk, fmode_t mode)
 unlock:
 	mutex_unlock(&dev->lock);
 	blktrans_dev_put(dev);
-	unlock_kernel();
+	mutex_unlock(&mtd_blkdevs_mutex);
 	return ret;
 }
 
@@ -256,7 +256,7 @@ static int blktrans_ioctl(struct block_device *bdev, fmode_t mode,
 	if (!dev)
 		return ret;
 
-	lock_kernel();
+	mutex_lock(&mtd_blkdevs_mutex);
 	mutex_lock(&dev->lock);
 
 	if (!dev->mtd)
@@ -271,7 +271,7 @@ static int blktrans_ioctl(struct block_device *bdev, fmode_t mode,
 	}
 unlock:
 	mutex_unlock(&dev->lock);
-	unlock_kernel();
+	mutex_unlock(&mtd_blkdevs_mutex);
 	blktrans_dev_put(dev);
 	return ret;
 }