[PATCH] block: add unlocked_ioctl support for block devices

This patch allows block device drivers to convert their ioctl functions to
unlocked_ioctl() like character devices and other subsystems.  All
functions that were called with the BKL held before are still used that
way, but I would not be surprised if it could be removed from the ioctl
functions in drivers/block/ioctl.c themselves.

As a side note, I found that compat_blkdev_ioctl() acquires the BKL as
well, which looks like a bug.  I have checked that every user of
disk->fops->compat_ioctl() in the current git tree gets the BKL itself, so
it could easily be removed from compat_blkdev_ioctl().

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 3622e952e98c..9b1278e21279 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -884,6 +884,7 @@ struct block_device_operations {
         int (*open) (struct inode *, struct file *);
         int (*release) (struct inode *, struct file *);
         int (*ioctl) (struct inode *, struct file *, unsigned, unsigned long);
+        long (*unlocked_ioctl) (struct file *, unsigned, unsigned long);
         long (*compat_ioctl) (struct file *, unsigned, unsigned long);
         int (*media_changed) (struct gendisk *);
         int (*revalidate_disk) (struct gendisk *);