[PATCH 07/13] iommu/amd_iommu: use dma_direct_{alloc,free}

From: Christoph Hellwig
Date: Mon Mar 05 2018 - 12:48:59 EST


This cleans up the code a lot by removing duplicate logic.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
drivers/iommu/Kconfig | 1 +
drivers/iommu/amd_iommu.c | 68 +++++++++++++++--------------------------------
2 files changed, 22 insertions(+), 47 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 0bf19423b588..83819d0cbf90 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -2600,51 +2600,32 @@ static void *alloc_coherent(struct device *dev, size_t size,
unsigned long attrs)
{
u64 dma_mask = dev->coherent_dma_mask;
- struct protection_domain *domain;
- struct dma_ops_domain *dma_dom;
- 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))
- return NULL;
+ struct protection_domain *domain = get_domain(dev);
+ bool is_direct = false;
+ void *virt_addr;

- dma_dom = to_dma_ops_domain(domain);
- size = PAGE_ALIGN(size);
- dma_mask = dev->coherent_dma_mask;
- flag &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
- flag |= __GFP_ZERO;
-
- page = alloc_pages(flag | __GFP_NOWARN, get_order(size));
- if (!page) {
- if (!gfpflags_allow_blocking(flag))
- return NULL;
-
- page = dma_alloc_from_contiguous(dev, size >> PAGE_SHIFT,
- get_order(size), flag);
- if (!page)
+ if (IS_ERR(domain)) {
+ if (PTR_ERR(domain) != -EINVAL)
return NULL;
+ is_direct = true;
}

+ virt_addr = dma_direct_alloc(dev, size, dma_addr, flag, attrs);
+ if (!virt_addr || is_direct)
+ return virt_addr;
+
if (!dma_mask)
dma_mask = *dev->dma_mask;

- *dma_addr = __map_single(dev, dma_dom, page_to_phys(page),
- size, DMA_BIDIRECTIONAL, dma_mask);
-
+ *dma_addr = __map_single(dev, to_dma_ops_domain(domain),
+ virt_to_phys(virt_addr), PAGE_ALIGN(size),
+ DMA_BIDIRECTIONAL, dma_mask);
if (*dma_addr == AMD_IOMMU_MAPPING_ERROR)
goto out_free;
-
- return page_address(page);
+ return virt_addr;

out_free:
-
- 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);
return NULL;
}

@@ -2655,24 +2636,17 @@ 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;
+ if (!IS_ERR(domain)) {
+ struct dma_ops_domain *dma_dom = to_dma_ops_domain(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