Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932317Ab3GaRpP (ORCPT ); Wed, 31 Jul 2013 13:45:15 -0400 Received: from smtp02.citrix.com ([66.165.176.63]:18346 "EHLO SMTP02.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754918Ab3GaRpM (ORCPT ); Wed, 31 Jul 2013 13:45:12 -0400 X-IronPort-AV: E=Sophos;i="4.89,788,1367971200"; d="scan'208";a="38588059" Date: Wed, 31 Jul 2013 18:44:59 +0100 From: Stefano Stabellini X-X-Sender: sstabellini@kaball.uk.xensource.com To: CC: , , Konrad Rzeszutek Wilk , Stefano Stabellini , Ian Campbell Subject: [PATCH RFC 0/8] enable swiotlb-xen on arm and arm64 Message-ID: User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2925 Lines: 70 Hi all, this patch series enables xen-swiotlb on arm and arm64. Considering that all guests, including dom0, run on xen on arm with second stage translation enabled, it follows that without an IOMMU no guests could actually drive the hardware. The solution for platforms without an IOMMU is to use swiotlb-xen, adapted to autotranslate guests. swiotlb-xen provides a set of dma_ops that can be used by Linux to setup a contiguous buffer in stage-2 addresses and use it for dma operations. Basically Linux asks Xen to make a buffer contiguous and gets the machine address for it. This buffer is going to be used by lib/swiotlb.c to allocate bounce buffers. The first 3 patches lay the groundwork on arm and arm64 to have alternative dma_ops and swiotlb. The forth patch moves Xen initialization earlier so that we already know whether we are running on Xen at the time of initializing dma_ops on the platform. The following patches adapt swiotlb-xen to autotranslate guests (guest with second stage translation in hardware) and provide an arm implementation of xen_create_contiguous_region. Feedback is very welcome. Cheers, Stefano Stefano Stabellini (8): arm: make SWIOTLB available arm: introduce a global dma_ops pointer arm64: do not initialize arm64_swiotlb if dma_ops is already set xen/arm,arm64: move Xen initialization earlier xen: introduce XENMEM_get_dma_buf and xen_put_dma_buf xen: make xen_create_contiguous_region return the dma address swiotlb-xen: support autotranslate guests xen/arm,arm64: enable SWIOTLB_XEN arch/arm/Kconfig | 8 ++ arch/arm/common/dmabounce.c | 10 +- arch/arm/include/asm/dma-mapping.h | 27 ++++++- arch/arm/include/asm/xen/hypervisor.h | 6 ++ arch/arm/include/asm/xen/page.h | 2 + arch/arm/kernel/setup.c | 2 + arch/arm/mm/dma-mapping.c | 3 + arch/arm/xen/Makefile | 2 +- arch/arm/xen/enlighten.c | 24 ++++-- arch/arm/xen/mm.c | 118 ++++++++++++++++++++++++++ arch/arm64/Kconfig | 1 + arch/arm64/kernel/setup.c | 2 + arch/arm64/mm/dma-mapping.c | 2 + arch/arm64/xen/Makefile | 2 +- arch/x86/xen/mmu.c | 4 +- drivers/xen/Kconfig | 1 - drivers/xen/swiotlb-xen.c | 147 +++++++++++++++++++++++++++++---- include/xen/interface/memory.h | 62 ++++++++++++++ include/xen/xen-ops.h | 3 +- 19 files changed, 391 insertions(+), 35 deletions(-) create mode 100644 arch/arm/xen/mm.c -- 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/