Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755309AbaBTQVa (ORCPT ); Thu, 20 Feb 2014 11:21:30 -0500 Received: from mail-ea0-f180.google.com ([209.85.215.180]:50713 "EHLO mail-ea0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754132AbaBTQV3 (ORCPT ); Thu, 20 Feb 2014 11:21:29 -0500 From: Julien Grall To: linux-kernel@vger.kernel.org, stefano.stabellini@eu.citrix.com Cc: linux-arm-kernel@lists.infradead.org, ian.campbell@citrix.com, xen-devel@lists.xenproject.org, Julien Grall , Russell King Subject: [PATCH 1/2] arm/xen: Introduce need_xen_dma_ops and use it in get_dma_ops Date: Thu, 20 Feb 2014 16:21:21 +0000 Message-Id: <1392913281-25483-1-git-send-email-julien.grall@linaro.org> X-Mailer: git-send-email 1.7.10.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If Xen programs the IOMMU to protect a device, it can safely use it's own DMA ops. Some devices may use DMA but are not protected by an IOMMU. A such device still need to use xen-swiotlb. This patch introduces need_xen_dma_ops which will check if a device needs to use xen DMA ops. For now, it's only check if Linux is running as DOM0. Signed-off-by: Julien Grall Cc: Russell King --- arch/arm/include/asm/dma-mapping.h | 5 ++--- arch/arm/include/asm/xen/dma-mapping.h | 13 +++++++++++++ arch/arm/include/asm/xen/hypervisor.h | 2 -- 3 files changed, 15 insertions(+), 5 deletions(-) create mode 100644 arch/arm/include/asm/xen/dma-mapping.h diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h index e701a4d..a40d077 100644 --- a/arch/arm/include/asm/dma-mapping.h +++ b/arch/arm/include/asm/dma-mapping.h @@ -11,8 +11,7 @@ #include #include -#include -#include +#include #define DMA_ERROR_CODE (~0) extern struct dma_map_ops arm_dma_ops; @@ -27,7 +26,7 @@ static inline struct dma_map_ops *__generic_dma_ops(struct device *dev) static inline struct dma_map_ops *get_dma_ops(struct device *dev) { - if (xen_initial_domain()) + if (need_xen_dma_ops(dev)) return xen_dma_ops; else return __generic_dma_ops(dev); diff --git a/arch/arm/include/asm/xen/dma-mapping.h b/arch/arm/include/asm/xen/dma-mapping.h new file mode 100644 index 0000000..002fc57 --- /dev/null +++ b/arch/arm/include/asm/xen/dma-mapping.h @@ -0,0 +1,13 @@ +#ifndef _ASM_ARM_XEN_DMA_MAPPING_H +#define _ASM_ARM_XEN_DMA_MAPPING_H + +#include + +extern struct dma_map_ops *xen_dma_ops; + +static inline bool need_xen_dma_ops(struct device *dev) +{ + return xen_initial_domain(); +} + +#endif /* _ASM_ARM_XEN_DMA_MAPPING_H */ diff --git a/arch/arm/include/asm/xen/hypervisor.h b/arch/arm/include/asm/xen/hypervisor.h index 1317ee4..d7ab99a 100644 --- a/arch/arm/include/asm/xen/hypervisor.h +++ b/arch/arm/include/asm/xen/hypervisor.h @@ -16,6 +16,4 @@ static inline enum paravirt_lazy_mode paravirt_get_lazy_mode(void) return PARAVIRT_LAZY_NONE; } -extern struct dma_map_ops *xen_dma_ops; - #endif /* _ASM_ARM_XEN_HYPERVISOR_H */ -- 1.7.10.4 -- 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/