Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932556Ab2HXIab (ORCPT ); Fri, 24 Aug 2012 04:30:31 -0400 Received: from hqemgate03.nvidia.com ([216.228.121.140]:4120 "EHLO hqemgate03.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932463Ab2HXIaU (ORCPT ); Fri, 24 Aug 2012 04:30:20 -0400 X-PGP-Universal: processed; by hqnvupgp07.nvidia.com on Fri, 24 Aug 2012 01:24:20 -0700 From: Hiroshi Doyu To: CC: Hiroshi Doyu , , , , , , , , , , , , , Subject: [v3 4/4] ARM: dma-mapping: IOMMU allocates pages from atomic_pool with GFP_ATOMIC Date: Fri, 24 Aug 2012 11:29:05 +0300 Message-ID: <1345796945-21115-5-git-send-email-hdoyu@nvidia.com> X-Mailer: git-send-email 1.7.5.4 In-Reply-To: <1345796945-21115-1-git-send-email-hdoyu@nvidia.com> References: <1345796945-21115-1-git-send-email-hdoyu@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2276 Lines: 78 Make use of the same atomic pool as DMA does, and skip a kernel page mapping which can involve sleep'able operations at allocating a kernel page table. Signed-off-by: Hiroshi Doyu --- arch/arm/mm/dma-mapping.c | 36 ++++++++++++++++++++++++++++++++++++ 1 files changed, 36 insertions(+), 0 deletions(-) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 58a852b..3ce152a 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -1205,6 +1205,34 @@ static struct page **__iommu_get_pages(void *cpu_addr, struct dma_attrs *attrs) return NULL; } +static void *__iommu_alloc_atomic(struct device *dev, size_t size, + dma_addr_t *handle) +{ + struct page *page; + void *addr; + + addr = __alloc_from_pool(size, &page); + if (!addr) + return NULL; + + *handle = __iommu_create_mapping(dev, &page, size); + if (*handle == DMA_ERROR_CODE) + goto err_mapping; + + return addr; + +err_mapping: + __free_from_pool(addr, size); + return NULL; +} + +static void __iommu_free_atomic(struct device *dev, struct page **pages, + dma_addr_t handle, size_t size) +{ + __iommu_remove_mapping(dev, handle, size); + __free_from_pool(page_address(pages[0]), size); +} + static void *arm_iommu_alloc_attrs(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp, struct dma_attrs *attrs) { @@ -1215,6 +1243,9 @@ static void *arm_iommu_alloc_attrs(struct device *dev, size_t size, *handle = DMA_ERROR_CODE; size = PAGE_ALIGN(size); + if (gfp & GFP_ATOMIC) + return __iommu_alloc_atomic(dev, size, handle); + pages = __iommu_alloc_buffer(dev, size, gfp); if (!pages) return NULL; @@ -1281,6 +1312,11 @@ void arm_iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr, return; } + if (__in_atomic_pool(cpu_addr, size)) { + __iommu_free_atomic(dev, pages, handle, size); + return; + } + if (!dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs)) { unmap_kernel_range((unsigned long)cpu_addr, size); vunmap(cpu_addr); -- 1.7.5.4 -- 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/