[PATCH 1/2] drm/ttm: Implement and export ttm_dma_page_alloc_enabled

[Koenig, Christian]

Am 25.01.19 um 14:05 schrieb Thomas Hellstrom:
> The vmwgfx driver needs to know whether the dma page pool is enabled
> to determine whether to refuse loading if the dma mode logic
> requests coherent memory from the dma page pool.
>
> Cc: "Koenig, Christian" <Christian.Koenig at amd.com>
> Signed-off-by: Thomas Hellstrom <thellstrom at vmware.com>
> ---
>   drivers/gpu/drm/ttm/ttm_page_alloc_dma.c | 11 +++++++++++
>   include/drm/ttm/ttm_page_alloc.h         |  4 ++++
>   2 files changed, 15 insertions(+)
>
> diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c
> index d594f7520b7b..adf8cc189ecc 100644
> --- a/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c
> +++ b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c
> @@ -1235,4 +1235,15 @@ int ttm_dma_page_alloc_debugfs(struct seq_file *m, void *data)
>   }
>   EXPORT_SYMBOL_GPL(ttm_dma_page_alloc_debugfs);
>   
> +/**
> + * ttm_dma_page_alloc_enabled - Is the dma page pool enabled?
> + *
> + * Returns true if the dma page pool is enabled. false otherwise.
> + */
> +bool ttm_dma_page_alloc_enabled(void)
> +{
> +	return !!_manager;
> +}
> +EXPORT_SYMBOL(ttm_dma_page_alloc_enabled);
> +

This is completely superfluous cause the manager is enabled as soon as 
it is compiled in.

You could just use "#if defined(CONFIG_SWIOTLB) || 
defined(CONFIG_INTEL_IOMMU)" instead.

Christian.

>   #endif
> diff --git a/include/drm/ttm/ttm_page_alloc.h b/include/drm/ttm/ttm_page_alloc.h
> index 4d9b019d253c..f810d389f5ad 100644
> --- a/include/drm/ttm/ttm_page_alloc.h
> +++ b/include/drm/ttm/ttm_page_alloc.h
> @@ -94,6 +94,8 @@ int ttm_dma_populate(struct ttm_dma_tt *ttm_dma, struct device *dev,
>   			struct ttm_operation_ctx *ctx);
>   void ttm_dma_unpopulate(struct ttm_dma_tt *ttm_dma, struct device *dev);
>   
> +bool ttm_dma_page_alloc_enabled(void);
> +
>   #else
>   static inline int ttm_dma_page_alloc_init(struct ttm_mem_global *glob,
>   					  unsigned max_pages)
> @@ -117,6 +119,8 @@ static inline void ttm_dma_unpopulate(struct ttm_dma_tt *ttm_dma,
>   				      struct device *dev)
>   {
>   }
> +
> +static inline bool ttm_dma_page_alloc_enabled(void) { return false; }
>   #endif
>   
>   #endif