Re: [rfc][patch 3/4] fs: new truncate sequence

[Nick Piggin <npiggin@suse.de>]

On Wed, Jul 08, 2009 at 07:07:17PM +0300, Boaz Harrosh wrote:
> On 07/08/2009 03:34 PM, Nick Piggin wrote:
> > On Wed, Jul 08, 2009 at 06:47:01AM -0400, Christoph Hellwig wrote:
> > Index: linux-2.6/fs/attr.c
> > ===================================================================
> > --- linux-2.6.orig/fs/attr.c
> > +++ linux-2.6/fs/attr.c
> > @@ -112,7 +112,12 @@ int inode_setattr(struct inode * inode,
> >  
> >  	if (ia_valid & ATTR_SIZE &&
> >  	    attr->ia_size != i_size_read(inode)) {
> > -		int error = vmtruncate(inode, attr->ia_size);
> > +		int error;
> > +
> > +		if (inode->i_op->new_truncate)
> > +			error = simple_setsize(inode, attr->ia_size);
> 
> I don't understand this branch.
> If a filesystem has been converted to set "i_op->new_truncate=true"
> then it must have been converted to intersect ->setattr and has set
> the i_size (And needs to clear ATTR_SIZE, why?)
> 
> All other cases of systems not converted, or systems that do not have
> ->truncate will fall to the "else" part.
> 
> before the removal of i_op->new_truncate you will need to do something
> with the systems that do not have ->truncate which will be a 
> .setattr = simple_setattr or something
> 
> So I don't understand this conditional

inode_setattr *is* our "simple_setattr".