Introduce new alloc/free/mmap methods that take attributes argument. alloc/free_coherent can be implemented on top of the new alloc/free calls with NULL attributes. dma_alloc_non_coherent can be implemented using DMA_ATTR_NONCOHERENT attribute, dma_alloc_writecombine can also use separate DMA_ATTR_WRITECOMBINE attribute. This way the drivers will get more generic, platform independent way of allocating dma memory buffers with specific parameters.
One more attribute can be usefull: DMA_ATTR_NOKERNELVADDR. Buffers with such attribute will not have valid kernel virtual address. They might be usefull for drivers that only exports the DMA buffers to userspace (like for example V4L2 or ALSA).
mmap method is introduced to let the drivers create a user space mapping for a DMA buffer in generic, architecture independent way.
TODO: update all dma_map_ops clients for all architectures
Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com Signed-off-by: Kyungmin Park kyungmin.park@samsung.com --- include/linux/dma-mapping.h | 13 +++++++++---- 1 files changed, 9 insertions(+), 4 deletions(-)
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index ba8319a..08a6fa8 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -16,10 +16,15 @@ enum dma_data_direction { };
struct dma_map_ops { - void* (*alloc_coherent)(struct device *dev, size_t size, - dma_addr_t *dma_handle, gfp_t gfp); - void (*free_coherent)(struct device *dev, size_t size, - void *vaddr, dma_addr_t dma_handle); + void* (*alloc)(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp, + struct dma_attrs *attrs); + void (*free)(struct device *dev, size_t size, + void *vaddr, dma_addr_t dma_handle, + struct dma_attrs *attrs); + int (*mmap)(struct device *, struct vm_area_struct *, + void *, dma_addr_t, size_t, struct dma_attrs *attrs); + dma_addr_t (*map_page)(struct device *dev, struct page *page, unsigned long offset, size_t size, enum dma_data_direction dir,