Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755869AbYJWOXS (ORCPT ); Thu, 23 Oct 2008 10:23:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752928AbYJWOXA (ORCPT ); Thu, 23 Oct 2008 10:23:00 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:51565 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752772AbYJWOW7 (ORCPT ); Thu, 23 Oct 2008 10:22:59 -0400 Date: Thu, 23 Oct 2008 16:22:43 +0200 From: Ingo Molnar To: FUJITA Tomonori Cc: linux-kernel@vger.kernel.org, tiwai@suse.de, joerg.roedel@amd.com Subject: Re: [PATCH] x86: restore the old swiotlb alloc_coherent behavior Message-ID: <20081023142243.GA22088@elte.hu> References: <20081023231230V.fujita.tomonori@lab.ntt.co.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20081023231230V.fujita.tomonori@lab.ntt.co.jp> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00,DNS_FROM_SECURITYSAGE autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] 0.0 DNS_FROM_SECURITYSAGE RBL: Envelope sender in blackholes.securitysage.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1535 Lines: 39 * FUJITA Tomonori wrote: > This restores the old swiotlb alloc_coherent behavior (before the > alloc_coherent rewrite): > > http://lkml.org/lkml/2008/8/12/200 > > The old alloc_coherent avoids GFP_DMA allocation first and if the > allocated address is not fit for the device's coherent_dma_mask, then > dma_alloc_coherent does GFP_DMA allocation. If it fails, > alloc_coherent calls swiotlb_alloc_coherent (in short, we rarely used > swiotlb_alloc_coherent). > > After the alloc_coherent rewrite, dma_alloc_coherent > (include/asm-x86/dma-mapping.h) directly calls swiotlb_alloc_coherent. > It means that we possibly can't handle a device having dma_masks > > 24bit < 32bits since swiotlb_alloc_coherent doesn't have the above > GFP_DMA retry mechanism. > > This patch fixes x86's swiotlb alloc_coherent to use the GFP_DMA retry > mechanism, which dma_generic_alloc_coherent() provides now > (pci-nommu.c and GART IOMMU driver also use > dma_generic_alloc_coherent). > > Signed-off-by: FUJITA Tomonori > --- > arch/x86/kernel/pci-swiotlb_64.c | 14 +++++++++++++- > 1 files changed, 13 insertions(+), 1 deletions(-) applied to tip/core/urgent (to after the two other iommu related patches) - thanks Fujita! Ingo -- 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/