From 13d9fead3daa0efa1b8bb6ae59650e4453b39128 Mon Sep 17 00:00:00 2001 From: FUJITA Tomonori Date: Wed, 10 Sep 2008 20:19:40 +0900 Subject: [PATCH] AMD IOMMU: avoid unnecessary low zone allocation in alloc_coherent x86's common alloc_coherent (dma_alloc_coherent in dma-mapping.h) sets up the gfp flag according to the device dma_mask but AMD IOMMU doesn't need it for devices that the IOMMU can do virtual mappings for. This patch avoids unnecessary low zone allocation. Signed-off-by: FUJITA Tomonori Signed-off-by: Joerg Roedel Signed-off-by: Ingo Molnar --- arch/x86/kernel/amd_iommu.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index a34d8e9..e486666 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -1173,6 +1173,9 @@ static void *alloc_coherent(struct device *dev, size_t size, if (!check_device(dev)) return NULL; + if (!get_device_resources(dev, &iommu, &domain, &devid)) + flag &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32); + virt_addr = (void *)__get_free_pages(flag, get_order(size)); if (!virt_addr) return 0; @@ -1180,8 +1183,6 @@ static void *alloc_coherent(struct device *dev, size_t size, memset(virt_addr, 0, size); paddr = virt_to_phys(virt_addr); - get_device_resources(dev, &iommu, &domain, &devid); - if (!iommu || !domain) { *dma_addr = (dma_addr_t)paddr; return virt_addr; -- 2.7.4