Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261292AbUCUUtk (ORCPT ); Sun, 21 Mar 2004 15:49:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261296AbUCUUtk (ORCPT ); Sun, 21 Mar 2004 15:49:40 -0500 Received: from phoenix.infradead.org ([213.86.99.234]:13317 "EHLO phoenix.infradead.org") by vger.kernel.org with ESMTP id S261292AbUCUUtg (ORCPT ); Sun, 21 Mar 2004 15:49:36 -0500 Date: Sun, 21 Mar 2004 20:49:31 +0000 From: Christoph Hellwig To: David Woodhouse Cc: William Lee Irwin III , rmk@arm.linux.org.uk, Andrew Morton , Andrea Arcangeli , linux-kernel@vger.kernel.org, torvalds@osdl.org Subject: Re: can device drivers return non-ram via vm_ops->nopage? Message-ID: <20040321204931.A11519@infradead.org> Mail-Followup-To: Christoph Hellwig , David Woodhouse , William Lee Irwin III , rmk@arm.linux.org.uk, Andrew Morton , Andrea Arcangeli , linux-kernel@vger.kernel.org, torvalds@osdl.org References: <20040320133025.GH9009@dualathlon.random> <20040320144022.GC2045@holomorphy.com> <20040320150621.GO9009@dualathlon.random> <20040320121345.2a80e6a0.akpm@osdl.org> <20040320205053.GJ2045@holomorphy.com> <20040320222639.K6726@flint.arm.linux.org.uk> <20040320224500.GP2045@holomorphy.com> <1079901914.17681.317.camel@imladris.demon.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <1079901914.17681.317.camel@imladris.demon.co.uk>; from dwmw2@infradead.org on Sun, Mar 21, 2004 at 08:45:14PM +0000 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 731 Lines: 16 On Sun, Mar 21, 2004 at 08:45:14PM +0000, David Woodhouse wrote: > There are machines where DMA to/from main memory _cannot_ be coherent > but we have some memory elsewhere, perhaps some SRAM which itself is > hanging off an I/O bus somewhere, which can be used. One of my toys is > currently running with dma_alloc_coherent() giving out memory from a PCI > video card, in fact. > > Using a PFN should be OK. And what exactly is a PFN without associated struct page supposed to mean? - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/