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

[Christoph Hellwig <hch@infradead.org>]

On Wed, Jul 08, 2009 at 08:32:25AM +0200, Nick Piggin wrote:
> Thanks for the patch, I think I will fold it in to the series. I
> think we probably do need to call simple_setsize in inode_setattr
> though (unless you propose to eventually convert every filesystem
> to define a .setattr). This would also require eg. your ext2
> conversion to strip ATTR_SIZE before passing through to inode_setattr.

Yes, we should eventually make .setattr mandatory.  Doing a default
action when a method lacks tends to cause more issues than it solves.

I'm happy to help in doing that part of the conversion (and also other
bits)

> >  int ext2_setattr(struct dentry *dentry, struct iattr *iattr)
> >  {
> >  	struct inode *inode = dentry->d_inode;
> >  	int error;
> >  
> > +	if (iattr->ia_valid & ATTR_SIZE) {
> > +		error = ext2_setsize(inode, iattr->ia_size);
> > +		if (error)
> > +			return error;
> > +	}
> > +
> >  	error = inode_change_ok(inode, iattr);
> >  	if (error)
> >  		return error;
> 
> Probably want to call inode_change_ok first here.

Right now I tried to no reorder anything versus the previous patch.

But yes, we should do all the checks first.  Possibly we can even add
a call to inode_newsize_ok to inode_change_ok, but I'd like to defer
that until all conversions are done and we can easily audit it.