Re: [PATCH] deprecate (un)register_ioctl32_conversion

[Christoph Hellwig]

On Thu, Jan 06, 2005 at 05:22:48PM +0200, Michael S. Tsirkin wrote:
> > +	if (!filp->f_op || !filp->f_op->ioctl)
> > +		goto do_ioctl;
> > +
> > +	if (filp->f_op || filp->f_op->compat_ioctl) {
> >  		error = filp->f_op->compat_ioctl(filp, cmd, arg);
> >  		goto out_fput;
> >  	}
> 
> So now if I dont have ->ioctl the ioctl_compat wont be called.
> What if I only have unlocked_ioctl?

Indeed.  In my test setup I didn't have a driver using both.  So let's
think a little more what checks we want.

The original intention (pre-patch) was that without an ioctl entry
we'd skip the hash table lookup and skip right to trying the few standard
ioctls.

So with ->compat_ioctl we should try that one first, then checking
for either ->ioctl or ->unlocked_ioctl beeing there.  Like the patch
below (this time it's actually untested because all my 64bit machines
are in use):


--- linux-2.6.10-mm2.orig/fs/compat.c	2005-01-06 11:40:18.831900000 +0100
+++ linux-2.6.10-mm2/fs/compat.c	2005-01-06 16:36:17.340977664 +0100
@@ -436,14 +436,15 @@
 	if (!filp)
 		goto out;
 
-	if (!filp->f_op) {
-		if (!filp->f_op->ioctl)
-			goto do_ioctl;
-	} else if (filp->f_op->compat_ioctl) {
+	if (filp->f_op && filp->f_op->compat_ioctl) {
 		error = filp->f_op->compat_ioctl(filp, cmd, arg);
 		goto out_fput;
 	}
 
+	if (!filp->f_op ||
+	    (!filp->f_op->ioctl && !filp->f_op->unlocked_ioctl))
+		goto do_ioctl;
+
 	down_read(&ioctl32_sem);
 	for (t = ioctl32_hash_table[ioctl32_hash(cmd)]; t; t = t->next) {
 		if (t->cmd == cmd)

> 
> 
> MST
---end quoted text---
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/