[PATCH 39/67] iommu/amd_iommu: use dma_direct_* helpers for the direct mapping case

Christoph Hellwig hch at lst.de
Fri Dec 29 19:18:43 AEDT 2017


This adds support for CMA allocations, but is otherwise identical.

Signed-off-by: Christoph Hellwig <hch at lst.de>
---
 drivers/iommu/Kconfig     |  1 +
 drivers/iommu/amd_iommu.c | 27 +++++++++------------------
 2 files changed, 10 insertions(+), 18 deletions(-)

diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index f3a21343e636..dc7c1914645d 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -107,6 +107,7 @@ config IOMMU_PGTABLES_L2
 # AMD IOMMU support
 config AMD_IOMMU
 	bool "AMD IOMMU support"
+	select DMA_DIRECT_OPS
 	select SWIOTLB
 	select PCI_MSI
 	select PCI_ATS
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index ea4734de5357..a2ad149ab0bf 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -2592,11 +2592,9 @@ static void *alloc_coherent(struct device *dev, size_t size,
 	struct page *page;
 
 	domain = get_domain(dev);
-	if (PTR_ERR(domain) == -EINVAL) {
-		page = alloc_pages(flag, get_order(size));
-		*dma_addr = page_to_phys(page);
-		return page_address(page);
-	} else if (IS_ERR(domain))
+	if (PTR_ERR(domain) == -EINVAL)
+		return dma_direct_alloc(dev, size, dma_addr, flag, attrs);
+	else if (IS_ERR(domain))
 		return NULL;
 
 	dma_dom   = to_dma_ops_domain(domain);
@@ -2642,24 +2640,17 @@ static void free_coherent(struct device *dev, size_t size,
 			  void *virt_addr, dma_addr_t dma_addr,
 			  unsigned long attrs)
 {
-	struct protection_domain *domain;
-	struct dma_ops_domain *dma_dom;
-	struct page *page;
+	struct protection_domain *domain = get_domain(dev);
 
-	page = virt_to_page(virt_addr);
 	size = PAGE_ALIGN(size);
 
-	domain = get_domain(dev);
-	if (IS_ERR(domain))
-		goto free_mem;
-
-	dma_dom = to_dma_ops_domain(domain);
+	if (!IS_ERR(domain)) {
+		struct dma_ops_domain *dma_dom = to_dma_ops_domain(domain);
 
-	__unmap_single(dma_dom, dma_addr, size, DMA_BIDIRECTIONAL);
+		__unmap_single(dma_dom, dma_addr, size, DMA_BIDIRECTIONAL);
+	}
 
-free_mem:
-	if (!dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT))
-		__free_pages(page, get_order(size));
+	dma_direct_free(dev, size, virt_addr, dma_addr, attrs);
 }
 
 /*
-- 
2.14.2



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