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, 8 insertions, 7 deletions

diff --git a/drivers/block/z2ram.c b/drivers/block/z2ram.c
index d75b2bb..dcd4cfc 100644
--- a/drivers/block/z2ram.c
+++ b/drivers/block/z2ram.c
@@ -33,7 +33,7 @@
 #include <linux/module.h>
 #include <linux/blkdev.h>
 #include <linux/bitops.h>
-#include <linux/smp_lock.h>
+#include <linux/mutex.h>
 #include <linux/slab.h>
 
 #include <asm/setup.h>
@@ -57,6 +57,7 @@ extern struct mem_info m68k_memory[NUM_MEMINFO];
 
 #define Z2RAM_CHUNK1024       ( Z2RAM_CHUNKSIZE >> 10 )
 
+static DEFINE_MUTEX(z2ram_mutex);
 static u_long *z2ram_map    = NULL;
 static u_long z2ram_size    = 0;
 static int z2_count         = 0;
@@ -154,7 +155,7 @@ static int z2_open(struct block_device *bdev, fmode_t mode)
 
     device = MINOR(bdev->bd_dev);
 
-    lock_kernel();
+    mutex_lock(&z2ram_mutex);
     if ( current_device != -1 && current_device != device )
     {
 	rc = -EBUSY;
@@ -296,25 +297,25 @@ static int z2_open(struct block_device *bdev, fmode_t mode)
 	set_capacity(z2ram_gendisk, z2ram_size >> 9);
     }
 
-    unlock_kernel();
+    mutex_unlock(&z2ram_mutex);
     return 0;
 
 err_out_kfree:
     kfree(z2ram_map);
 err_out:
-    unlock_kernel();
+    mutex_unlock(&z2ram_mutex);
     return rc;
 }
 
 static int
 z2_release(struct gendisk *disk, fmode_t mode)
 {
-    lock_kernel();
+    mutex_lock(&z2ram_mutex);
     if ( current_device == -1 ) {
-    	unlock_kernel();
+    	mutex_unlock(&z2ram_mutex);
     	return 0;
     }
-    unlock_kernel();
+    mutex_unlock(&z2ram_mutex);
     /*
      * FIXME: unmap memory
      */