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iommu/dma: Implement dma_{map,unmap}_resource()

PATCH New Robin Murphy 3 participants 4 messages Nov 14, 2016

Subsystems (3)
arm64 IOMMU IOMMU DMA-API layer
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Robin Murphy

author maintainer
#0 lore raw

PATCH v4 1/2 iommu/dma: Implement dma_{map,unmap}_resource()

With the new dma_{map,unmap}_resource() functions added to the DMA API for the benefit of cases like slave DMA, add suitable implementations to the arsenal of our generic layer. Since cache maintenance should not be a concern, these can both be standalone callback implementations without the need for arch code wrappers.

CC Joerg Roedel <[email protected]>
Signed-off-by Robin Murphy <[email protected]>

---

v4: Add the missed static qualifier (thanks Catalin)

 drivers/iommu/dma-iommu.c | 24 +++++++++++++++++++++---
 include/linux/dma-iommu.h |  4 ++++
 2 files changed, 25 insertions(+), 3 deletions(-)
drivers/iommu/dma-iommu.c +21 -3
index c5ab8667e6f2..2db0d641cf45 100644
@@ -432,13 +432,12 @@ int iommu_dma_mmap(struct page **pages, size_t size, struct vm_area_struct *vma)
 	return ret;
 }
 
-dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page,
-		unsigned long offset, size_t size, int prot)
+static dma_addr_t __iommu_dma_map(struct device *dev, phys_addr_t phys,
+		size_t size, int prot)
 {
 	dma_addr_t dma_addr;
 	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
 	struct iova_domain *iovad = cookie_iovad(domain);
-	phys_addr_t phys = page_to_phys(page) + offset;
 	size_t iova_off = iova_offset(iovad, phys);
 	size_t len = iova_align(iovad, size + iova_off);
 	struct iova *iova = __alloc_iova(domain, len, dma_get_mask(dev));

@@ -454,6 +453,12 @@ dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page,
 	return dma_addr + iova_off;
 }
 
+dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page,
+		unsigned long offset, size_t size, int prot)
+{
+	return __iommu_dma_map(dev, page_to_phys(page) + offset, size, prot);
+}
+
 void iommu_dma_unmap_page(struct device *dev, dma_addr_t handle, size_t size,
 		enum dma_data_direction dir, unsigned long attrs)
 {

@@ -624,6 +629,19 @@ void iommu_dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
 	__iommu_dma_unmap(iommu_get_domain_for_dev(dev), sg_dma_address(sg));
 }
 
+dma_addr_t iommu_dma_map_resource(struct device *dev, phys_addr_t phys,
+		size_t size, enum dma_data_direction dir, unsigned long attrs)
+{
+	return __iommu_dma_map(dev, phys, size,
+			dma_direction_to_prot(dir, false) | IOMMU_MMIO);
+}
+
+void iommu_dma_unmap_resource(struct device *dev, dma_addr_t handle,
+		size_t size, enum dma_data_direction dir, unsigned long attrs)
+{
+	__iommu_dma_unmap(iommu_get_domain_for_dev(dev), handle);
+}
+
 int iommu_dma_supported(struct device *dev, u64 mask)
 {
 	/*
include/linux/dma-iommu.h +4 -0
index 32c589062bd9..7f7e9a7e3839 100644
@@ -61,6 +61,10 @@ void iommu_dma_unmap_page(struct device *dev, dma_addr_t handle, size_t size,
 		enum dma_data_direction dir, unsigned long attrs);
 void iommu_dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
 		enum dma_data_direction dir, unsigned long attrs);
+dma_addr_t iommu_dma_map_resource(struct device *dev, phys_addr_t phys,
+		size_t size, enum dma_data_direction dir, unsigned long attrs);
+void iommu_dma_unmap_resource(struct device *dev, dma_addr_t handle,
+		size_t size, enum dma_data_direction dir, unsigned long attrs);
 int iommu_dma_supported(struct device *dev, u64 mask);
 int iommu_dma_mapping_error(struct device *dev, dma_addr_t dma_addr);
Signature · 1 line
2.10.2.dirty
author maintainer
#1 lore raw

PATCH v4 2/2 arm64: Wire up iommu_dma_{map, unmap}_resource()

With no coherency to worry about, just plug'em straight in.

Acked-by Catalin Marinas <[email protected]>
Signed-off-by Robin Murphy <[email protected]>
---
 arch/arm64/mm/dma-mapping.c | 2 ++
 1 file changed, 2 insertions(+)
arch/arm64/mm/dma-mapping.c +2 -0
index 3f74d0d98de6..5cd0a383b14b 100644
@@ -796,6 +796,8 @@ static struct dma_map_ops iommu_dma_ops = {
 	.sync_single_for_device = __iommu_sync_single_for_device,
 	.sync_sg_for_cpu = __iommu_sync_sg_for_cpu,
 	.sync_sg_for_device = __iommu_sync_sg_for_device,
+	.map_resource = iommu_dma_map_resource,
+	.unmap_resource = iommu_dma_unmap_resource,
 	.dma_supported = iommu_dma_supported,
 	.mapping_error = iommu_dma_mapping_error,
 };
Signature · 1 line
2.10.2.dirty
maintainer
#2 lore raw

PATCH v4 1/2 iommu/dma: Implement dma_{map,unmap}_resource()

In reply to Robin Murphy
Quoted 8 lines · Robin Murphy

With the new dma_{map,unmap}_resource() functions added to the DMA API for the benefit of cases like slave DMA, add suitable implementations to the arsenal of our generic layer. Since cache maintenance should not be a concern, these can both be standalone callback implementations without the need for arch code wrappers.

CC Joerg Roedel <[email protected]>
Signed-off-by Robin Murphy <[email protected]>

FWIW:

Reviewed-by Catalin Marinas <[email protected]>
maintainer Applied
#3 lore raw

PATCH v4 1/2 iommu/dma: Implement dma_{map,unmap}_resource()

In reply to Robin Murphy
Quoted 8 lines · Robin Murphy

With the new dma_{map,unmap}_resource() functions added to the DMA API for the benefit of cases like slave DMA, add suitable implementations to the arsenal of our generic layer. Since cache maintenance should not be a concern, these can both be standalone callback implementations without the need for arch code wrappers.

CC Joerg Roedel <[email protected]>
Signed-off-by Robin Murphy <[email protected]>
Quoted 7 lines

---

v4: Add the missed static qualifier (thanks Catalin)

 drivers/iommu/dma-iommu.c | 24 +++++++++++++++++++++---
 include/linux/dma-iommu.h |  4 ++++
 2 files changed, 25 insertions(+), 3 deletions(-)

Applied both, thanks Robin.