[PATCH 04/19] dma-iommu: remove the flush_page callback

From: Christoph Hellwig
Date: Mon Jan 14 2019 - 04:42:26 EST


We now have a arch_dma_prep_coherent architecture hook that is used
for the generic DMA remap allocator, and we should use the same
interface for the dma-iommu code.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
arch/arm64/mm/dma-mapping.c | 8 +-------
drivers/iommu/dma-iommu.c | 14 ++++----------
include/linux/dma-iommu.h | 3 +--
3 files changed, 6 insertions(+), 19 deletions(-)

diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index fb0908456a1f..75fe7273a1e4 100644
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -104,12 +104,6 @@ arch_initcall(arm64_dma_init);
#include <linux/platform_device.h>
#include <linux/amba/bus.h>

-/* Thankfully, all cache ops are by VA so we can ignore phys here */
-static void flush_page(struct device *dev, const void *virt, phys_addr_t phys)
-{
- __dma_flush_area(virt, PAGE_SIZE);
-}
-
static void *__iommu_alloc_attrs(struct device *dev, size_t size,
dma_addr_t *handle, gfp_t gfp,
unsigned long attrs)
@@ -186,7 +180,7 @@ static void *__iommu_alloc_attrs(struct device *dev, size_t size,
struct page **pages;

pages = iommu_dma_alloc(dev, iosize, gfp, attrs, ioprot,
- handle, flush_page);
+ handle);
if (!pages)
return NULL;

diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 4f5546a103d8..d6a437385b26 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -22,6 +22,7 @@
#include <linux/acpi_iort.h>
#include <linux/device.h>
#include <linux/dma-iommu.h>
+#include <linux/dma-noncoherent.h>
#include <linux/gfp.h>
#include <linux/huge_mm.h>
#include <linux/iommu.h>
@@ -533,8 +534,6 @@ void iommu_dma_free(struct device *dev, struct page **pages, size_t size,
* @attrs: DMA attributes for this allocation
* @prot: IOMMU mapping flags
* @handle: Out argument for allocated DMA handle
- * @flush_page: Arch callback which must ensure PAGE_SIZE bytes from the
- * given VA/PA are visible to the given non-coherent device.
*
* If @size is less than PAGE_SIZE, then a full CPU page will be allocated,
* but an IOMMU which supports smaller pages might not map the whole thing.
@@ -543,8 +542,7 @@ void iommu_dma_free(struct device *dev, struct page **pages, size_t size,
* or NULL on failure.
*/
struct page **iommu_dma_alloc(struct device *dev, size_t size, gfp_t gfp,
- unsigned long attrs, int prot, dma_addr_t *handle,
- void (*flush_page)(struct device *, const void *, phys_addr_t))
+ unsigned long attrs, int prot, dma_addr_t *handle)
{
struct iommu_domain *domain = iommu_get_dma_domain(dev);
struct iommu_dma_cookie *cookie = domain->iova_cookie;
@@ -580,12 +578,8 @@ struct page **iommu_dma_alloc(struct device *dev, size_t size, gfp_t gfp,
for (i = 0; i < count; i++) {
phys_addr_t phys = page_to_phys(pages[i]);

- if (!(prot & IOMMU_CACHE)) {
- void *vaddr = kmap_atomic(pages[i]);
-
- flush_page(dev, vaddr, phys);
- kunmap_atomic(vaddr);
- }
+ if (!(prot & IOMMU_CACHE))
+ arch_dma_prep_coherent(pages[i], PAGE_SIZE);

if (iommu_map(domain, iova + mapped, phys, PAGE_SIZE, prot))
goto out_unmap;
diff --git a/include/linux/dma-iommu.h b/include/linux/dma-iommu.h
index 65aa888c2768..59e606f78626 100644
--- a/include/linux/dma-iommu.h
+++ b/include/linux/dma-iommu.h
@@ -43,8 +43,7 @@ int dma_info_to_prot(enum dma_data_direction dir, bool coherent,
* the arch code to take care of attributes and cache maintenance
*/
struct page **iommu_dma_alloc(struct device *dev, size_t size, gfp_t gfp,
- unsigned long attrs, int prot, dma_addr_t *handle,
- void (*flush_page)(struct device *, const void *, phys_addr_t));
+ unsigned long attrs, int prot, dma_addr_t *handle);
void iommu_dma_free(struct device *dev, struct page **pages, size_t size,
dma_addr_t *handle);

--
2.20.1