block: push down BKL into .locked_ioctl

As a preparation for the removal of the big kernel
lock in the block layer, this removes the BKL
from the common ioctl handling code, moving it
into every single driver still using it.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

drivers/scsi/sr.c

@@ -44,6 +44,7 @@
 #include <linux/init.h>
 #include <linux/blkdev.h>
 #include <linux/mutex.h>
+#include <linux/smp_lock.h>
 #include <linux/slab.h>
 #include <asm/uaccess.h>
 
@@ -493,6 +494,8 @@ static int sr_block_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
 	void __user *argp = (void __user *)arg;
 	int ret;
 
+	lock_kernel();
+
 	/*
 	 * Send SCSI addressing ioctls directly to mid level, send other
 	 * ioctls to cdrom/block level.
@@ -500,12 +503,13 @@ static int sr_block_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
 	switch (cmd) {
 	case SCSI_IOCTL_GET_IDLUN:
 	case SCSI_IOCTL_GET_BUS_NUMBER:
-		return scsi_ioctl(sdev, cmd, argp);
+		ret = scsi_ioctl(sdev, cmd, argp);
+		goto out;
 	}
 
 	ret = cdrom_ioctl(&cd->cdi, bdev, mode, cmd, arg);
 	if (ret != -ENOSYS)
-		return ret;
+		goto out;
 
 	/*
 	 * ENODEV means that we didn't recognise the ioctl, or that we
@@ -516,8 +520,12 @@ static int sr_block_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
 	ret = scsi_nonblockable_ioctl(sdev, cmd, argp,
 					(mode & FMODE_NDELAY) != 0);
 	if (ret != -ENODEV)
-		return ret;
-	return scsi_ioctl(sdev, cmd, argp);
+		goto out;
+	ret = scsi_ioctl(sdev, cmd, argp);
+
+out:
+	unlock_kernel();
+	return ret;
 }
 
 static int sr_block_media_changed(struct gendisk *disk)
@@ -531,7 +539,7 @@ static const struct block_device_operations sr_bdops =
 	.owner		= THIS_MODULE,
 	.open		= sr_block_open,
 	.release	= sr_block_release,
-	.locked_ioctl	= sr_block_ioctl,
+	.ioctl		= sr_block_ioctl,
 	.media_changed	= sr_block_media_changed,
 	/* 
 	 * No compat_ioctl for now because sr_block_ioctl never