From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751434AbbJBUQ5 (ORCPT ); Fri, 2 Oct 2015 16:16:57 -0400 Received: from e32.co.us.ibm.com ([32.97.110.150]:35369 "EHLO e32.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751039AbbJBUQ4 (ORCPT ); Fri, 2 Oct 2015 16:16:56 -0400 X-IBM-Helo: d03dlp02.boulder.ibm.com X-IBM-MailFrom: nacc@linux.vnet.ibm.com X-IBM-RcptTo: linux-kernel@vger.kernel.org Date: Fri, 2 Oct 2015 13:16:47 -0700 From: Nishanth Aravamudan To: Matthew Wilcox Cc: Keith Busch , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Alexey Kardashevskiy , David Gibson , Christoph Hellwig , linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Subject: [PATCH 2/5 v2] powerpc/dma-mapping: override dma_get_page_shift Message-ID: <20151002201647.GH8040@linux.vnet.ibm.com> References: <20151002171606.GA41011@linux.vnet.ibm.com> <20151002200953.GB40695@linux.vnet.ibm.com> <20151002201142.GC40695@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20151002201142.GC40695@linux.vnet.ibm.com> X-Operating-System: Linux 3.13.0-40-generic (x86_64) User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15100220-0005-0000-0000-000018A6BCE0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Power, the kernel's page size can differ from the IOMMU's page size, so we need to override the generic implementation, which always returns the kernel's page size. Lookup the IOMMU's page size from struct iommu_table, if available. Fallback to the kernel's page size, otherwise. Signed-off-by: Nishanth Aravamudan diff --git a/arch/powerpc/include/asm/dma-mapping.h b/arch/powerpc/include/asm/dma-mapping.h index 7f522c0..c5638f4 100644 --- a/arch/powerpc/include/asm/dma-mapping.h +++ b/arch/powerpc/include/asm/dma-mapping.h @@ -125,6 +125,9 @@ static inline void set_dma_offset(struct device *dev, dma_addr_t off) #define HAVE_ARCH_DMA_SET_MASK 1 extern int dma_set_mask(struct device *dev, u64 dma_mask); +#define HAVE_ARCH_DMA_GET_PAGE_SHIFT 1 +extern unsigned long dma_get_page_shift(struct device *dev); + #include extern int __dma_set_mask(struct device *dev, u64 dma_mask); diff --git a/arch/powerpc/kernel/dma.c b/arch/powerpc/kernel/dma.c index 59503ed..e805af2 100644 --- a/arch/powerpc/kernel/dma.c +++ b/arch/powerpc/kernel/dma.c @@ -335,6 +335,15 @@ int dma_set_mask(struct device *dev, u64 dma_mask) } EXPORT_SYMBOL(dma_set_mask); +unsigned long dma_get_page_shift(struct device *dev) +{ + struct iommu_table *tbl = get_iommu_table_base(dev); + if (tbl) + return tbl->it_page_shift; + return PAGE_SHIFT; +} +EXPORT_SYMBOL(dma_get_page_shift); + u64 __dma_get_required_mask(struct device *dev) { struct dma_map_ops *dma_ops = get_dma_ops(dev);