From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jes Sorensen Date: Fri, 17 Mar 2006 09:15:32 +0000 Subject: Re: [patch] mspec - special memory driver and do_no_pfn handler Message-Id: <441A7E34.90508@sgi.com> List-Id: References: <20060316163728.06f49c00.akpm@osdl.org> <1142571490.9022.37.camel@localhost.localdomain> In-Reply-To: <1142571490.9022.37.camel@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Benjamin Herrenschmidt Cc: Linus Torvalds , Andrew Morton , linux-kernel@vger.kernel.org, linux-ia64@vger.kernel.org, hch@lst.de, cotte@de.ibm.com, Hugh Dickins Benjamin Herrenschmidt wrote: >> Quite frankly, I don't think nopfn() is a good interface. It's only usable >> for one single thing, so trying to claim that it's a generic VM op is >> really not valid. If (and that's a big if) we need this interface, we >> should just do it inside mm/memory.c instead of playing games as if it was >> generic. > > Or just use sparsemem and create struct pages for your hw :) we do that > for SPUs on Cell, works like a charm. Well then the question is, would it simplify the code using no_pfn in this case? Hacking up fake struct page entries seems even more of a hack to me. Cheers, Jes