Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933332AbXJRTV2 (ORCPT ); Thu, 18 Oct 2007 15:21:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S933529AbXJRTUz (ORCPT ); Thu, 18 Oct 2007 15:20:55 -0400 Received: from srv5.dvmed.net ([207.36.208.214]:34934 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933499AbXJRTUy (ORCPT ); Thu, 18 Oct 2007 15:20:54 -0400 Message-ID: <4717B1FC.6040907@garzik.org> Date: Thu, 18 Oct 2007 15:20:28 -0400 From: Jeff Garzik User-Agent: Thunderbird 2.0.0.5 (X11/20070727) MIME-Version: 1.0 To: Linus Torvalds CC: Jens Axboe , David Miller , fujita.tomonori@lab.ntt.co.jp, mingo@elte.hu, linux-kernel@vger.kernel.org, alan@lxorguk.ukuu.org.uk, tomof@acm.org Subject: Re: [bug] ata subsystem related crash with latest -git References: <20071018080048O.fujita.tomonori@lab.ntt.co.jp> <20071017.181907.63126798.davem@davemloft.net> <20071018082145.GK5063@kernel.dk> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -4.4 (----) X-Spam-Report: SpamAssassin version 3.1.9 on srv5.dvmed.net summary: Content analysis details: (-4.4 points, 5.0 required) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 830 Lines: 20 Linus Torvalds wrote: > Very few drivers should care so much about the *page* itself (or the > offset). That's something that the generic allocation code etc cares > about, but the driver is almost bound to care mostly about the actual DMA > address, so adding that helper function that abstracts the sg access would > be helpful in hiding some of the cruft? FWIW libata cares about both. When doing DMA, it cares about the DMA address. When doing PIO, it cares about the actual page, because it does a kmap before sending the data through a 16-bit/32-bit data FIFO. Jeff - 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/