Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765120AbXJRRBl (ORCPT ); Thu, 18 Oct 2007 13:01:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756776AbXJRRBe (ORCPT ); Thu, 18 Oct 2007 13:01:34 -0400 Received: from brick.kernel.dk ([87.55.233.238]:21549 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756754AbXJRRBd (ORCPT ); Thu, 18 Oct 2007 13:01:33 -0400 Date: Thu, 18 Oct 2007 19:01:29 +0200 From: Jens Axboe To: Linus Torvalds Cc: David Miller , fujita.tomonori@lab.ntt.co.jp, mingo@elte.hu, linux-kernel@vger.kernel.org, jgarzik@pobox.com, alan@lxorguk.ukuu.org.uk, tomof@acm.org Subject: Re: [bug] ata subsystem related crash with latest -git Message-ID: <20071018170128.GF10674@kernel.dk> References: <20071018080048O.fujita.tomonori@lab.ntt.co.jp> <20071017.181907.63126798.davem@davemloft.net> <20071018082145.GK5063@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1152 Lines: 35 On Thu, Oct 18 2007, Linus Torvalds wrote: > > > On Thu, 18 Oct 2007, Jens Axboe wrote: > > - unsigned long addr = page_to_phys(s->page) + s->offset; > > + unsigned long addr = page_to_phys(sg_page(s)) + s->offset; > > Umm. May I suggest (I haven't read the whole thread yet, maybe somebody > else already did) that > > static inline unsigned long sg_phys(struct scatterlist *sg) > { > return page_to_phys(sg_page(sg)) + sg->offset; > } > > would be a good thing to have? Sure thing, it's used quite a lot. > 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? I'll add it to the mix. -- Jens Axboe - 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/