From patchwork Wed Jan 10 08:00:25 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 10154235 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 9C9A560231 for ; Wed, 10 Jan 2018 08:03:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 92E2320500 for ; Wed, 10 Jan 2018 08:03:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 87747223A0; Wed, 10 Jan 2018 08:03:21 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2B56A20500 for ; Wed, 10 Jan 2018 08:03:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754597AbeAJIDP (ORCPT ); Wed, 10 Jan 2018 03:03:15 -0500 Received: from bombadil.infradead.org ([65.50.211.133]:55594 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965536AbeAJICM (ORCPT ); Wed, 10 Jan 2018 03:02:12 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=References:In-Reply-To:Message-Id: Date:Subject:Cc:To:From:Sender:Reply-To:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=6gHJAzejuzPCxSNHlsCF3La5tUazsQTiDBdJCkzFyac=; b=aUWBZrXjqFzIDymQbAhGCCCFm e3/nQMzcienQMt2GfaWOb6QQEHyIgE5vFbjlcuZ+k6Ic+oZ/ferRmFMTUHfxAMpqBYSol4I6tl5jI am9D212a32y6OQW3+TeTBGaSgvz4iPJmf2CXciRZrOGzvd4KlOlHn9QC01BOq3n0h0EvP2RZFCt9J 6OVnW/uiGg0PFOtf8xUYdMCFXtjXV6fRNI3DmFtm7CGI1Fx4fr2+I3u/zMOwI2YIYPFL0EIkvF0DW +Qu+8QFo2Eakd5AXMZq700vDe7TprtqMwvKaMsnyCv63/IsUXEfyetkixVAFnf7ooU6VqnRk1vf58 CIswrA+WQ==; Received: from clnet-p099-196.ikbnet.co.at ([83.175.99.196] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.89 #1 (Red Hat Linux)) id 1eZBKl-0005p1-Ox; Wed, 10 Jan 2018 08:02:04 +0000 From: Christoph Hellwig To: iommu@lists.linux-foundation.org Cc: Konrad Rzeszutek Wilk , linux-alpha@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-c6x-dev@linux-c6x.org, linux-cris-kernel@axis.com, linux-hexagon@vger.kernel.org, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-metag@vger.kernel.org, Michal Simek , linux-mips@linux-mips.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, patches@groups.riscv.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, Guan Xuetao , x86@kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 31/33] dma-direct: reject too small dma masks Date: Wed, 10 Jan 2018 09:00:25 +0100 Message-Id: <20180110080027.13879-32-hch@lst.de> X-Mailer: git-send-email 2.14.2 In-Reply-To: <20180110080027.13879-1-hch@lst.de> References: <20180110080027.13879-1-hch@lst.de> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Signed-off-by: Christoph Hellwig Reviewed-by: Robin Murphy --- include/linux/dma-direct.h | 1 + lib/dma-direct.c | 19 +++++++++++++++++++ 2 files changed, 20 insertions(+) diff --git a/include/linux/dma-direct.h b/include/linux/dma-direct.h index 4788bf0bf683..bcdb1a3e4b1f 100644 --- a/include/linux/dma-direct.h +++ b/include/linux/dma-direct.h @@ -42,5 +42,6 @@ void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs); void dma_direct_free(struct device *dev, size_t size, void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs); +int dma_direct_supported(struct device *dev, u64 mask); #endif /* _LINUX_DMA_DIRECT_H */ diff --git a/lib/dma-direct.c b/lib/dma-direct.c index 784a68dfdbe3..40b1f92f2214 100644 --- a/lib/dma-direct.c +++ b/lib/dma-direct.c @@ -122,6 +122,24 @@ static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, return nents; } +int dma_direct_supported(struct device *dev, u64 mask) +{ +#ifdef CONFIG_ZONE_DMA + if (mask < DMA_BIT_MASK(ARCH_ZONE_DMA_BITS)) + return 0; +#else + /* + * Because 32-bit DMA masks are so common we expect every architecture + * to be able to satisfy them - either by not supporting more physical + * memory, or by providing a ZONE_DMA32. If neither is the case, the + * architecture needs to use an IOMMU instead of the direct mapping. + */ + if (mask < DMA_BIT_MASK(32)) + return 0; +#endif + return 1; +} + static int dma_direct_mapping_error(struct device *dev, dma_addr_t dma_addr) { return dma_addr == DIRECT_MAPPING_ERROR; @@ -132,6 +150,7 @@ const struct dma_map_ops dma_direct_ops = { .free = dma_direct_free, .map_page = dma_direct_map_page, .map_sg = dma_direct_map_sg, + .dma_supported = dma_direct_supported, .mapping_error = dma_direct_mapping_error, }; EXPORT_SYMBOL(dma_direct_ops);