From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4600BD9F.8030609@yahoo.com.au> Date: Wed, 21 Mar 2007 16:07:43 +1100 From: Nick Piggin MIME-Version: 1.0 Subject: Re: [PATCH 1/7] Introduce the pagetable_operations and associated helper macros. References: <20070319200502.17168.17175.stgit@localhost.localdomain> <20070319200513.17168.52238.stgit@localhost.localdomain> <4600B216.3010505@yahoo.com.au> <20070321045214.GE2986@holomorphy.com> In-Reply-To: <20070321045214.GE2986@holomorphy.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: William Lee Irwin III Cc: Adam Litke , Andrew Morton , Arjan van de Ven , Christoph Hellwig , Ken Chen , linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: William Lee Irwin III wrote: > Adam Litke wrote: > >>> struct vm_operations_struct * vm_ops; >>>+ const struct pagetable_operations_struct * pagetable_ops; > > > On Wed, Mar 21, 2007 at 03:18:30PM +1100, Nick Piggin wrote: > >>Can you remind me why this isn't in vm_ops? >>Also, it is going to be hugepage-only, isn't it? So should the naming be >>changed to reflect that? And #ifdef it... > > > ISTR potential ppc64 users coming out of the woodwork for something I > didn't recognize the name of, but I may be confusing that with your > patch. I can implement additional users (and useful ones at that) > needing this in particular if desired. Yes I would be interested in seeing useful additional users of this that cannot use our regular virtual memory, before making it a general thing. I just don't want to see proliferation of these things, if possible. > Adam Litke wrote: > >>>+struct pagetable_operations_struct { >>>+ int (*fault)(struct mm_struct *mm, > > > On Wed, Mar 21, 2007 at 03:18:30PM +1100, Nick Piggin wrote: > >>I got dibs on fault ;) >>My callback is a sanitised one that basically abstracts the details of the >>virtual memory mapping away, so it is usable by drivers and filesystems. >>You actually want to bypass the normal fault handling because it doesn't >>know how to deal with your virtual memory mapping. Hmm, the best suggestion >>I can come up with is handle_mm_fault... unless you can think of a better >>name for me to use. > > > Two fault handling methods callbacks raise an eyebrow over here at least. > I was vaguely hoping for unification of the fault handling callbacks. I don't know if it would be so clean to do that as they are at different levels. Adam's fault is before the VM translation (and bypasses it), and mine is after. -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org