[PATCH v4 1/6] dma-mapping: prepare dma_map_ops to conversion to physical address

[Leon Romanovsky <leon@xxxxxxxxxx>]

From: Leon Romanovsky <leonro@xxxxxxxxxx>

Add new .map_phys() and .unmap_phys() callbacks to dma_map_ops as a
preparation to replace .map_page() and .unmap_page() respectively.

Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxx>
---
 include/linux/dma-map-ops.h |  7 +++++++
 kernel/dma/mapping.c        |  4 ++++
 kernel/dma/ops_helpers.c    | 12 ++++++++++--
 3 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/include/linux/dma-map-ops.h b/include/linux/dma-map-ops.h
index 71f5b30254159..25603cb273769 100644
--- a/include/linux/dma-map-ops.h
+++ b/include/linux/dma-map-ops.h
@@ -37,6 +37,13 @@ struct dma_map_ops {
        void (*unmap_page)(struct device *dev, dma_addr_t dma_handle,
                        size_t size, enum dma_data_direction dir,
                        unsigned long attrs);
+
+       dma_addr_t (*map_phys)(struct device *dev, phys_addr_t phys,
+                       size_t size, enum dma_data_direction dir,
+                       unsigned long attrs);
+       void (*unmap_phys)(struct device *dev, dma_addr_t dma_handle,
+                       size_t size, enum dma_data_direction dir,
+                       unsigned long attrs);
        /*
         * map_sg should return a negative error code on error. See
         * dma_map_sgtable() for a list of appropriate error codes
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index fe7472f13b106..4080aebe5debb 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -169,6 +169,8 @@ dma_addr_t dma_map_phys(struct device *dev, phys_addr_t 
phys, size_t size,
                addr = dma_direct_map_phys(dev, phys, size, dir, attrs);
        else if (use_dma_iommu(dev))
                addr = iommu_dma_map_phys(dev, phys, size, dir, attrs);
+       else if (ops->map_phys)
+               addr = ops->map_phys(dev, phys, size, dir, attrs);
        else if (is_mmio) {
                if (!ops->map_resource)
                        return DMA_MAPPING_ERROR;
@@ -223,6 +225,8 @@ void dma_unmap_phys(struct device *dev, dma_addr_t addr, 
size_t size,
                dma_direct_unmap_phys(dev, addr, size, dir, attrs);
        else if (use_dma_iommu(dev))
                iommu_dma_unmap_phys(dev, addr, size, dir, attrs);
+       else if (ops->unmap_phys)
+               ops->unmap_phys(dev, addr, size, dir, attrs);
        else if (is_mmio) {
                if (ops->unmap_resource)
                        ops->unmap_resource(dev, addr, size, dir, attrs);
diff --git a/kernel/dma/ops_helpers.c b/kernel/dma/ops_helpers.c
index 6f9d604d9d406..1eccbdbc99c1e 100644
--- a/kernel/dma/ops_helpers.c
+++ b/kernel/dma/ops_helpers.c
@@ -64,6 +64,7 @@ struct page *dma_common_alloc_pages(struct device *dev, 
size_t size,
 {
        const struct dma_map_ops *ops = get_dma_ops(dev);
        struct page *page;
+       phys_addr_t phys;
 
        page = dma_alloc_contiguous(dev, size, gfp);
        if (!page)
@@ -71,9 +72,13 @@ struct page *dma_common_alloc_pages(struct device *dev, 
size_t size,
        if (!page)
                return NULL;
 
+       phys = page_to_phys(page);
        if (use_dma_iommu(dev))
-               *dma_handle = iommu_dma_map_phys(dev, page_to_phys(page), size,
-                                                dir, DMA_ATTR_SKIP_CPU_SYNC);
+               *dma_handle = iommu_dma_map_phys(dev, phys, size, dir,
+                                                DMA_ATTR_SKIP_CPU_SYNC);
+       else if (ops->map_phys)
+               *dma_handle = ops->map_phys(dev, phys, size, dir,
+                                           DMA_ATTR_SKIP_CPU_SYNC);
        else
                *dma_handle = ops->map_page(dev, page, 0, size, dir,
                                            DMA_ATTR_SKIP_CPU_SYNC);
@@ -94,6 +99,9 @@ void dma_common_free_pages(struct device *dev, size_t size, 
struct page *page,
        if (use_dma_iommu(dev))
                iommu_dma_unmap_phys(dev, dma_handle, size, dir,
                                     DMA_ATTR_SKIP_CPU_SYNC);
+       else if (ops->unmap_phys)
+               ops->unmap_phys(dev, dma_handle, size, dir,
+                               DMA_ATTR_SKIP_CPU_SYNC);
        else if (ops->unmap_page)
                ops->unmap_page(dev, dma_handle, size, dir,
                                DMA_ATTR_SKIP_CPU_SYNC);
-- 
2.51.0