Re: [PATCH 02/11] xen/arm: use dev_is_dma_coherent

Stefano Stabellini
2019-08-29T22:42:51Z

On Mon, 26 Aug 2019, Christoph Hellwig wrote:
> Use the dma-noncoherent dev_is_dma_coherent helper instead of the home
> grown variant. Note that both are always initialized to the same
> value in arch_setup_dma_ops.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: Julien Grall <julien.grall@arm.com>

Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>

> ---
> arch/arm/include/asm/dma-mapping.h | 6 ------
> arch/arm/xen/mm.c | 12 ++++++------
> arch/arm64/include/asm/dma-mapping.h | 9 ---------
> 3 files changed, 6 insertions(+), 21 deletions(-)
>
> diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h
> index dba9355e2484..bdd80ddbca34 100644
> --- a/arch/arm/include/asm/dma-mapping.h
> +++ b/arch/arm/include/asm/dma-mapping.h
> @@ -91,12 +91,6 @@ static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
> }
> #endif
>
> -/* do not use this function in a driver */
> -static inline bool is_device_dma_coherent(struct device *dev)
> -{
> - return dev->archdata.dma_coherent;
> -}
> -
> /**
> * arm_dma_alloc - allocate consistent memory for DMA
> * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
> diff --git a/arch/arm/xen/mm.c b/arch/arm/xen/mm.c
> index d33b77e9add3..90574d89d0d4 100644
> --- a/arch/arm/xen/mm.c
> +++ b/arch/arm/xen/mm.c
> @@ -1,6 +1,6 @@
> // SPDX-License-Identifier: GPL-2.0-only
> #include <linux/cpu.h>
> -#include <linux/dma-mapping.h>
> +#include <linux/dma-noncoherent.h>
> #include <linux/gfp.h>
> #include <linux/highmem.h>
> #include <linux/export.h>
> @@ -99,7 +99,7 @@ void __xen_dma_map_page(struct device *hwdev, struct page *page,
> dma_addr_t dev_addr, unsigned long offset, size_t size,
> enum dma_data_direction dir, unsigned long attrs)
> {
> - if (is_device_dma_coherent(hwdev))
> + if (dev_is_dma_coherent(hwdev))
> return;
> if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
> return;
> @@ -112,7 +112,7 @@ void __xen_dma_unmap_page(struct device *hwdev, dma_addr_t handle,
> unsigned long attrs)
>
> {
> - if (is_device_dma_coherent(hwdev))
> + if (dev_is_dma_coherent(hwdev))
> return;
> if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
> return;
> @@ -123,7 +123,7 @@ void __xen_dma_unmap_page(struct device *hwdev, dma_addr_t handle,
> void __xen_dma_sync_single_for_cpu(struct device *hwdev,
> dma_addr_t handle, size_t size, enum dma_data_direction dir)
> {
> - if (is_device_dma_coherent(hwdev))
> + if (dev_is_dma_coherent(hwdev))
> return;
> __xen_dma_page_dev_to_cpu(hwdev, handle, size, dir);
> }
> @@ -131,7 +131,7 @@ void __xen_dma_sync_single_for_cpu(struct device *hwdev,
> void __xen_dma_sync_single_for_device(struct device *hwdev,
> dma_addr_t handle, size_t size, enum dma_data_direction dir)
> {
> - if (is_device_dma_coherent(hwdev))
> + if (dev_is_dma_coherent(hwdev))
> return;
> __xen_dma_page_cpu_to_dev(hwdev, handle, size, dir);
> }
> @@ -159,7 +159,7 @@ bool xen_arch_need_swiotlb(struct device *dev,
> * memory and we are not able to flush the cache.
> */
> return (!hypercall_cflush && (xen_pfn != bfn) &&
> - !is_device_dma_coherent(dev));
> + !dev_is_dma_coherent(dev));
> }
>
> int xen_create_contiguous_region(phys_addr_t pstart, unsigned int order,
> diff --git a/arch/arm64/include/asm/dma-mapping.h b/arch/arm64/include/asm/dma-mapping.h
> index bdcb0922a40c..67243255a858 100644
> --- a/arch/arm64/include/asm/dma-mapping.h
> +++ b/arch/arm64/include/asm/dma-mapping.h
> @@ -18,14 +18,5 @@ static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
> return NULL;
> }
>
> -/*
> - * Do not use this function in a driver, it is only provided for
> - * arch/arm/mm/xen.c, which is used by arm64 as well.
> - */
> -static inline bool is_device_dma_coherent(struct device *dev)
> -{
> - return dev->dma_coherent;
> -}
> -
> #endif /* __KERNEL__ */
> #endif /* __ASM_DMA_MAPPING_H */
> --
> 2.20.1