iommu/dma: Move domain lookup into __iommu_dma_{map,unmap}

Most of the callers don't care, and the couple that do already have the
domain to hand for other reasons are in slow paths where the (trivial)
overhead of a repeated lookup will be utterly immaterial.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
[hch: dropped the hunk touching iommu_dma_get_msi_page to avoid a
 conflict with another series]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/dma-iommu.c

@@ -448,9 +448,10 @@ static void iommu_dma_free_iova(struct iommu_dma_cookie *cookie,
 				size >> iova_shift(iovad));
 }
 
-static void __iommu_dma_unmap(struct iommu_domain *domain, dma_addr_t dma_addr,
+static void __iommu_dma_unmap(struct device *dev, dma_addr_t dma_addr,
 		size_t size)
 {
+	struct iommu_domain *domain = iommu_get_dma_domain(dev);
 	struct iommu_dma_cookie *cookie = domain->iova_cookie;
 	struct iova_domain *iovad = &cookie->iovad;
 	size_t iova_off = iova_offset(iovad, dma_addr);
@@ -465,8 +466,9 @@ static void __iommu_dma_unmap(struct iommu_domain *domain, dma_addr_t dma_addr,
 }
 
 static dma_addr_t __iommu_dma_map(struct device *dev, phys_addr_t phys,
-		size_t size, int prot, struct iommu_domain *domain)
+		size_t size, int prot)
 {
+	struct iommu_domain *domain = iommu_get_dma_domain(dev);
 	struct iommu_dma_cookie *cookie = domain->iova_cookie;
 	size_t iova_off = 0;
 	dma_addr_t iova;
@@ -565,7 +567,7 @@ static struct page **__iommu_dma_alloc_pages(struct device *dev,
 static void __iommu_dma_free(struct device *dev, struct page **pages,
 		size_t size, dma_addr_t *handle)
 {
-	__iommu_dma_unmap(iommu_get_dma_domain(dev), *handle, size);
+	__iommu_dma_unmap(dev, *handle, size);
 	__iommu_dma_free_pages(pages, PAGE_ALIGN(size) >> PAGE_SHIFT);
 	*handle = DMA_MAPPING_ERROR;
 }
@@ -718,14 +720,13 @@ static void iommu_dma_sync_sg_for_device(struct device *dev,
 static 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,
-			iommu_get_dma_domain(dev));
+	return __iommu_dma_map(dev, page_to_phys(page) + offset, size, prot);
 }
 
 static void __iommu_dma_unmap_page(struct device *dev, dma_addr_t handle,
 		size_t size, enum dma_data_direction dir, unsigned long attrs)
 {
-	__iommu_dma_unmap(iommu_get_dma_domain(dev), handle, size);
+	__iommu_dma_unmap(dev, handle, size);
 }
 
 static dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page,
@@ -734,11 +735,10 @@ static dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page,
 {
 	phys_addr_t phys = page_to_phys(page) + offset;
 	bool coherent = dev_is_dma_coherent(dev);
+	int prot = dma_info_to_prot(dir, coherent, attrs);
 	dma_addr_t dma_handle;
 
-	dma_handle =__iommu_dma_map(dev, phys, size,
-			dma_info_to_prot(dir, coherent, attrs),
-			iommu_get_dma_domain(dev));
+	dma_handle =__iommu_dma_map(dev, phys, size, prot);
 	if (!coherent && !(attrs & DMA_ATTR_SKIP_CPU_SYNC) &&
 	    dma_handle != DMA_MAPPING_ERROR)
 		arch_sync_dma_for_device(dev, phys, size, dir);
@@ -750,7 +750,7 @@ static void iommu_dma_unmap_page(struct device *dev, dma_addr_t dma_handle,
 {
 	if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
 		iommu_dma_sync_single_for_cpu(dev, dma_handle, size, dir);
-	__iommu_dma_unmap(iommu_get_dma_domain(dev), dma_handle, size);
+	__iommu_dma_unmap(dev, dma_handle, size);
 }
 
 /*
@@ -931,21 +931,20 @@ static void iommu_dma_unmap_sg(struct device *dev, struct scatterlist *sg,
 		sg = tmp;
 	}
 	end = sg_dma_address(sg) + sg_dma_len(sg);
-	__iommu_dma_unmap(iommu_get_dma_domain(dev), start, end - start);
+	__iommu_dma_unmap(dev, start, end - start);
 }
 
 static 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_info_to_prot(dir, false, attrs) | IOMMU_MMIO,
-			iommu_get_dma_domain(dev));
+			dma_info_to_prot(dir, false, attrs) | IOMMU_MMIO);
 }
 
 static 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_dma_domain(dev), handle, size);
+	__iommu_dma_unmap(dev, handle, size);
 }
 
 static void *iommu_dma_alloc(struct device *dev, size_t size,
@@ -1222,7 +1221,7 @@ static struct iommu_dma_msi_page *iommu_dma_get_msi_page(struct device *dev,
 	if (!msi_page)
 		return NULL;
 
-	iova = __iommu_dma_map(dev, msi_addr, size, prot, domain);
+	iova = __iommu_dma_map(dev, msi_addr, size, prot);
 	if (iova == DMA_MAPPING_ERROR)
 		goto out_free_page;