Re: [JANITOR PROPOSAL] Switch ioctl functions to ->unlocked_ioctl

Vadim Lobanov
2008-01-09T23:42:39Z

On Wednesday 09 January 2008 03:05:45 pm Alasdair G Kergon wrote:
> On Wed, Jan 09, 2008 at 04:58:46PM -0600, Chris Friesen wrote:
> > Alasdair G Kergon wrote:
> > >On Wed, Jan 09, 2008 at 11:46:03PM +0100, Andi Kleen wrote:
> > >>struct inode *inode = file->f_dentry->d_inode;
> > >
> > >And oops if that's not defined?
> >
> > Isn't this basically identical to what was being passed in to .ioctl()?
>
> Not in every case, unless someone's been through and created fake
> structures in all the remaining places that pass in a NULL 'file' because
> there isn't one available.

>From 2.6.23's fs/ioctl.c - do_ioctl():

if (filp->f_op->unlocked_ioctl) {
error = filp->f_op->unlocked_ioctl(filp, cmd, arg);
if (error == -ENOIOCTLCMD)
error = -EINVAL;
goto out;
} else if (filp->f_op->ioctl) {
lock_kernel();
error = filp->f_op->ioctl(filp->f_path.dentry->d_inode,
filp, cmd, arg);
unlock_kernel();
}

As a sidenote, please don't use f_dentry and f_vfsmnt, since they are just
#defines for the correct fields. They were meant to be temporary transition
helpers, but (alas) have refused to die thus far. If noone beats me to it,
I'll take a look-see at deprecating them all the way.

-- Vadim Lobanov