Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753878AbaDONKx (ORCPT ); Tue, 15 Apr 2014 09:10:53 -0400 Received: from mail-pd0-f169.google.com ([209.85.192.169]:47893 "EHLO mail-pd0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754900AbaDONJQ (ORCPT ); Tue, 15 Apr 2014 09:09:16 -0400 From: Akinobu Mita To: linux-kernel@vger.kernel.org, akpm@linux-foundation.org Cc: Akinobu Mita , Marek Szyprowski , Konrad Rzeszutek Wilk , David Woodhouse , Don Dutile , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Andi Kleen , x86@kernel.org, iommu@lists.linux-foundation.org Subject: [PATCH v3 3/5] intel-iommu: integrate DMA CMA Date: Tue, 15 Apr 2014 22:08:47 +0900 Message-Id: <1397567329-3771-4-git-send-email-akinobu.mita@gmail.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1397567329-3771-1-git-send-email-akinobu.mita@gmail.com> References: <1397567329-3771-1-git-send-email-akinobu.mita@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This adds support for the DMA Contiguous Memory Allocator for intel-iommu. This change enables dma_alloc_coherent() to allocate big contiguous memory. It is achieved in the same way as nommu_dma_ops currently does, i.e. trying to allocate memory by dma_alloc_from_contiguous() and alloc_pages() is used as a fallback. Cc: Marek Szyprowski Cc: Konrad Rzeszutek Wilk Cc: David Woodhouse Cc: Don Dutile Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Andi Kleen Cc: x86@kernel.org Cc: iommu@lists.linux-foundation.org Signed-off-by: Akinobu Mita --- * Changes from v2 - Fix gfp flags check for __GFP_ATOMIC, reported by Marek Szyprowski - Rebased on current Linus tree drivers/iommu/intel-iommu.c | 32 ++++++++++++++++++++++++-------- 1 file changed, 24 insertions(+), 8 deletions(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index cdb97c4..78c68cb 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -3185,7 +3185,7 @@ static void *intel_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t flags, struct dma_attrs *attrs) { - void *vaddr; + struct page *page = NULL; int order; size = PAGE_ALIGN(size); @@ -3200,17 +3200,31 @@ static void *intel_alloc_coherent(struct device *dev, size_t size, flags |= GFP_DMA32; } - vaddr = (void *)__get_free_pages(flags, order); - if (!vaddr) + if (flags & __GFP_WAIT) { + unsigned int count = size >> PAGE_SHIFT; + + page = dma_alloc_from_contiguous(dev, count, order); + if (page && iommu_no_mapping(dev) && + page_to_phys(page) + size > dev->coherent_dma_mask) { + dma_release_from_contiguous(dev, page, count); + page = NULL; + } + } + + if (!page) + page = alloc_pages(flags, order); + if (!page) return NULL; - memset(vaddr, 0, size); + memset(page_address(page), 0, size); - *dma_handle = __intel_map_single(dev, virt_to_bus(vaddr), size, + *dma_handle = __intel_map_single(dev, page_to_phys(page), size, DMA_BIDIRECTIONAL, dev->coherent_dma_mask); if (*dma_handle) - return vaddr; - free_pages((unsigned long)vaddr, order); + return page_address(page); + if (!dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT)) + __free_pages(page, order); + return NULL; } @@ -3218,12 +3232,14 @@ static void intel_free_coherent(struct device *dev, size_t size, void *vaddr, dma_addr_t dma_handle, struct dma_attrs *attrs) { int order; + struct page *page = virt_to_page(vaddr); size = PAGE_ALIGN(size); order = get_order(size); intel_unmap_page(dev, dma_handle, size, DMA_BIDIRECTIONAL, NULL); - free_pages((unsigned long)vaddr, order); + if (!dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT)) + __free_pages(page, order); } static void intel_unmap_sg(struct device *dev, struct scatterlist *sglist, -- 1.8.3.2 -- 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/