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>

drivers/ide/ide-cd.c

@@ -31,7 +31,6 @@
 #include <linux/delay.h>
 #include <linux/timer.h>
 #include <linux/seq_file.h>
-#include <linux/smp_lock.h>
 #include <linux/slab.h>
 #include <linux/interrupt.h>
 #include <linux/errno.h>
@@ -52,6 +51,7 @@
 
 #include "ide-cd.h"
 
+static DEFINE_MUTEX(ide_cd_mutex);
 static DEFINE_MUTEX(idecd_ref_mutex);
 
 static void ide_cd_release(struct device *);
@@ -1602,7 +1602,7 @@ static int idecd_open(struct block_device *bdev, fmode_t mode)
 	struct cdrom_info *info;
 	int rc = -ENXIO;
 
-	lock_kernel();
+	mutex_lock(&ide_cd_mutex);
 	info = ide_cd_get(bdev->bd_disk);
 	if (!info)
 		goto out;
@@ -1611,7 +1611,7 @@ static int idecd_open(struct block_device *bdev, fmode_t mode)
 	if (rc < 0)
 		ide_cd_put(info);
 out:
-	unlock_kernel();
+	mutex_unlock(&ide_cd_mutex);
 	return rc;
 }
 
@@ -1619,11 +1619,11 @@ static int idecd_release(struct gendisk *disk, fmode_t mode)
 {
 	struct cdrom_info *info = ide_drv_g(disk, cdrom_info);
 
-	lock_kernel();
+	mutex_lock(&ide_cd_mutex);
 	cdrom_release(&info->devinfo, mode);
 
 	ide_cd_put(info);
-	unlock_kernel();
+	mutex_unlock(&ide_cd_mutex);
 
 	return 0;
 }
@@ -1694,9 +1694,9 @@ static int idecd_ioctl(struct block_device *bdev, fmode_t mode,
 {
 	int ret;
 
-	lock_kernel();
+	mutex_lock(&ide_cd_mutex);
 	ret = idecd_locked_ioctl(bdev, mode, cmd, arg);
-	unlock_kernel();
+	mutex_unlock(&ide_cd_mutex);
 
 	return ret;
 }