Re: [PATCHv9 2/6] dma-debug: add support for resource mappings

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Niklas,

Thank you for the patch.

On Wednesday 10 Aug 2016 13:22:15 Niklas Söderlund wrote:
> A MMIO mapped resource can not be represented by a struct page so a new
> debug type is needed to handle this. This patch add such type and
> functionality to add/remove entries and how to translate them to a
> physical address.
> 
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>

Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

> ---
>  include/linux/dma-debug.h | 19 +++++++++++++++++
>  lib/dma-debug.c           | 52 +++++++++++++++++++++++++++++++++++++++++--
>  2 files changed, 69 insertions(+), 2 deletions(-)
> 
> diff --git a/include/linux/dma-debug.h b/include/linux/dma-debug.h
> index fe8cb61..c7d844f 100644
> --- a/include/linux/dma-debug.h
> +++ b/include/linux/dma-debug.h
> @@ -56,6 +56,13 @@ extern void debug_dma_alloc_coherent(struct device *dev,
> size_t size, extern void debug_dma_free_coherent(struct device *dev, size_t
> size, void *virt, dma_addr_t addr);
> 
> +extern void debug_dma_map_resource(struct device *dev, phys_addr_t addr,
> +				   size_t size, int direction,
> +				   dma_addr_t dma_addr);
> +
> +extern void debug_dma_unmap_resource(struct device *dev, dma_addr_t
> dma_addr, +				     size_t size, int direction);
> +
>  extern void debug_dma_sync_single_for_cpu(struct device *dev,
>  					  dma_addr_t dma_handle, size_t size,
>  					  int direction);
> @@ -141,6 +148,18 @@ static inline void debug_dma_free_coherent(struct
> device *dev, size_t size, {
>  }
> 
> +static inline void debug_dma_map_resource(struct device *dev, phys_addr_t
> addr, +					  size_t size, int direction,
> +					  dma_addr_t dma_addr)
> +{
> +}
> +
> +static inline void debug_dma_unmap_resource(struct device *dev,
> +					    dma_addr_t dma_addr, size_t size,
> +					    int direction)
> +{
> +}
> +
>  static inline void debug_dma_sync_single_for_cpu(struct device *dev,
>  						 dma_addr_t dma_handle,
>  						 size_t size, int direction)
> diff --git a/lib/dma-debug.c b/lib/dma-debug.c
> index fcfa193..2ba086b 100644
> --- a/lib/dma-debug.c
> +++ b/lib/dma-debug.c
> @@ -43,6 +43,7 @@ enum {
>  	dma_debug_page,
>  	dma_debug_sg,
>  	dma_debug_coherent,
> +	dma_debug_resource,
>  };
> 
>  enum map_err_types {
> @@ -150,8 +151,9 @@ static const char *const maperr2str[] = {
>  	[MAP_ERR_CHECKED] = "dma map error checked",
>  };
> 
> -static const char *type2name[4] = { "single", "page",
> -				    "scather-gather", "coherent" };
> +static const char *type2name[5] = { "single", "page",
> +				    "scather-gather", "coherent",
> +				    "resource" };
> 
>  static const char *dir2name[4] = { "DMA_BIDIRECTIONAL", "DMA_TO_DEVICE",
>  				   "DMA_FROM_DEVICE", "DMA_NONE" };
> @@ -399,6 +401,9 @@ static void hash_bucket_del(struct dma_debug_entry
> *entry)
> 
>  static unsigned long long phys_addr(struct dma_debug_entry *entry)
>  {
> +	if (entry->type == dma_debug_resource)
> +		return __pfn_to_phys(entry->pfn) + entry->offset;
> +
>  	return page_to_phys(pfn_to_page(entry->pfn)) + entry->offset;
>  }
> 
> @@ -1495,6 +1500,49 @@ void debug_dma_free_coherent(struct device *dev,
> size_t size, }
>  EXPORT_SYMBOL(debug_dma_free_coherent);
> 
> +void debug_dma_map_resource(struct device *dev, phys_addr_t addr, size_t
> size, +			    int direction, dma_addr_t dma_addr)
> +{
> +	struct dma_debug_entry *entry;
> +
> +	if (unlikely(dma_debug_disabled()))
> +		return;
> +
> +	entry = dma_entry_alloc();
> +	if (!entry)
> +		return;
> +
> +	entry->type		= dma_debug_resource;
> +	entry->dev		= dev;
> +	entry->pfn		= __phys_to_pfn(addr);
> +	entry->offset		= offset_in_page(addr);
> +	entry->size		= size;
> +	entry->dev_addr		= dma_addr;
> +	entry->direction	= direction;
> +	entry->map_err_type	= MAP_ERR_NOT_CHECKED;
> +
> +	add_dma_entry(entry);
> +}
> +EXPORT_SYMBOL(debug_dma_map_resource);
> +
> +void debug_dma_unmap_resource(struct device *dev, dma_addr_t dma_addr,
> +			      size_t size, int direction)
> +{
> +	struct dma_debug_entry ref = {
> +		.type           = dma_debug_resource,
> +		.dev            = dev,
> +		.dev_addr       = dma_addr,
> +		.size           = size,
> +		.direction      = direction,
> +	};
> +
> +	if (unlikely(dma_debug_disabled()))
> +		return;
> +
> +	check_unmap(&ref);
> +}
> +EXPORT_SYMBOL(debug_dma_unmap_resource);
> +
>  void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t
> dma_handle, size_t size, int direction)
>  {

-- 
Regards,

Laurent Pinchart