Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753310AbZFDUL3 (ORCPT ); Thu, 4 Jun 2009 16:11:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752423AbZFDULV (ORCPT ); Thu, 4 Jun 2009 16:11:21 -0400 Received: from mail-bw0-f213.google.com ([209.85.218.213]:41651 "EHLO mail-bw0-f213.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752331AbZFDULU (ORCPT ); Thu, 4 Jun 2009 16:11:20 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=V/AwmCvtkT8B60llUa998aqr04yWG8UbBr245V59vgmubkAGOjORH/khI+ATp9a35K zo+fL5c2/8MavwwAMUOiKU8U4dA5xamR85UAafA4BTq4lucUGkhUDE/VQH1Jif16FbCc U+y2C46TKDZiJAiqQzuAPQJxc2i/NTILyLi7k= MIME-Version: 1.0 In-Reply-To: <200906041747.04310.arnd@arndb.de> References: <200906011111.28521.arnd@arndb.de> <200906041235.34686.arnd@arndb.de> <20090605000424E.fujita.tomonori@lab.ntt.co.jp> <200906041747.04310.arnd@arndb.de> Date: Thu, 4 Jun 2009 22:11:20 +0200 Message-ID: <10f740e80906041311r1b9f870at308b56ac392cb5b8@mail.gmail.com> Subject: Re: [PATCH] asm-generic: add dma-mapping-linear.h From: Geert Uytterhoeven To: Arnd Bergmann Cc: FUJITA Tomonori , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1497 Lines: 36 On Thu, Jun 4, 2009 at 18:47, Arnd Bergmann wrote: > On Thursday 04 June 2009, FUJITA Tomonori wrote: >> On Thu, 4 Jun 2009 12:35:34 +0000 >> Arnd Bergmann wrote: >> If I correctly understand DMA-API.txt, dma_alloc_noncoherent can >> return either consistent or non-consistent memory. On architectures >> that return consistent memory via dma_alloc_noncoherent, >> dma_cache_sync should be null. dma_cache_sync() is supposed to be used >> only with the returned buffers of dma_alloc_noncoherent(). > > Good point. This is unfortunately not what is implemented on many > architectures, which #define dma_alloc_noncoherent dma_alloc_coherent > but still provide a synchronizing operation in dma_cache_sync(). > > dma_alloc_noncoherent is actually only implemented on parisc, mips > and m68k. And m68k is a false positive, as it just uses a static inline wrapper instead of a define to map it to dma_alloc_coherent(). Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- 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/