Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261427AbUCUWmP (ORCPT ); Sun, 21 Mar 2004 17:42:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261430AbUCUWmP (ORCPT ); Sun, 21 Mar 2004 17:42:15 -0500 Received: from imladris.demon.co.uk ([193.237.130.41]:32408 "EHLO baythorne.infradead.org") by vger.kernel.org with ESMTP id S261427AbUCUWmO (ORCPT ); Sun, 21 Mar 2004 17:42:14 -0500 Subject: Re: can device drivers return non-ram via vm_ops->nopage? From: David Woodhouse To: Jeff Garzik Cc: Russell King , Linus Torvalds , Christoph Hellwig , William Lee Irwin III , Andrew Morton , Andrea Arcangeli , linux-kernel@vger.kernel.org In-Reply-To: <405E1859.5030906@pobox.com> References: <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> <20040321204931.A11519@infradead.org> <1079902670.17681.324.camel@imladris.demon.co.uk> <20040321222327.D26708@flint.arm.linux.org.uk> <405E1859.5030906@pobox.com> Content-Type: text/plain Message-Id: <1079908923.17681.453.camel@imladris.demon.co.uk> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.5 (1.4.5-8.dwmw2.2) Date: Sun, 21 Mar 2004 22:42:03 +0000 Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by baythorne.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 810 Lines: 20 On Sun, 2004-03-21 at 17:34 -0500, Jeff Garzik wrote: > Tell driver writers to call a standard platform function with a > {dma|mmio|pio|vmalloc} handle+size+len for {dma|mmio|pio|vmalloc} mmap > setup, and {fault|nopage} handler. ;-) IMO they shouldn't have to care > about the details. Don't let drivers see the {fault|nopage} handler. On most arches it can probably continue to be nopage(); other arches may use the newly-proposed fault() or perhaps just put all the PTEs in place up front. The driver shouldn't be given an opportunity to care. -- dwmw2 - 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/