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, 5 insertions, 4 deletions

diff --git a/drivers/block/aoe/aoeblk.c b/drivers/block/aoe/aoeblk.c
index a946929..f21c237 100644
--- a/drivers/block/aoe/aoeblk.c
+++ b/drivers/block/aoe/aoeblk.c
@@ -12,9 +12,10 @@
 #include <linux/slab.h>
 #include <linux/genhd.h>
 #include <linux/netdevice.h>
-#include <linux/smp_lock.h>
+#include <linux/mutex.h>
 #include "aoe.h"
 
+static DEFINE_MUTEX(aoeblk_mutex);
 static struct kmem_cache *buf_pool_cache;
 
 static ssize_t aoedisk_show_state(struct device *dev,
@@ -125,16 +126,16 @@ aoeblk_open(struct block_device *bdev, fmode_t mode)
 	struct aoedev *d = bdev->bd_disk->private_data;
 	ulong flags;
 
-	lock_kernel();
+	mutex_lock(&aoeblk_mutex);
 	spin_lock_irqsave(&d->lock, flags);
 	if (d->flags & DEVFL_UP) {
 		d->nopen++;
 		spin_unlock_irqrestore(&d->lock, flags);
-		unlock_kernel();
+		mutex_unlock(&aoeblk_mutex);
 		return 0;
 	}
 	spin_unlock_irqrestore(&d->lock, flags);
-	unlock_kernel();
+	mutex_unlock(&aoeblk_mutex);
 	return -ENODEV;
 }