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

From: Christoph Hellwig
Date: Fri Dec 29 2017 - 03:22:33 EST


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

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
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