[dm-devel] Re: [PATCH] remove unneded lock_kernel in drivers/md/dm.c and use unlocked_ioctl.

[Alasdair G Kergon <agk redhat com>]

On Mon, Jul 30, 2007 at 11:23:49PM -0300, Diego Woitasen wrote:
> -static int dm_blk_ioctl(struct inode *inode, struct file *file,
> -			unsigned int cmd, unsigned long arg)
> +static long dm_blk_ioctl(struct file *file, unsigned int cmd, unsigned long arg)

> -	/* We don't really need this lock, but we do need 'inode'. */
> -	unlock_kernel();
> +	inode = file->f_path.dentry->d_inode;

Have the call paths that pass a NULL 'file' parameter down all been
changed?  If not, perhaps pass the 'inode' parameter into
unlocked_ioctl(), as happens with ioctl(), to get rid of the lock.

Alasdair
-- 
agk redhat com