Re: [PATCH 02/11] dma-mapping: replace dmam_alloc_noncoherent with dmam_alloc_attrs

[Christoph Hellwig <hch@infradead.org>]

Tejun, does this look ok to you?

On Fri, Jun 16, 2017 at 09:17:07AM +0200, Christoph Hellwig wrote:
> dmam_alloc_noncoherent is a trivial wrapper around dmam_alloc_attrs,
> that hardcodes one particular flag.  Make the devres code more
> flexible by allowing the callers to pass arbitrary flags.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>  Documentation/driver-model/devres.txt |  2 +-
>  drivers/base/dma-mapping.c            | 36 ++++++++++++++++-------------------
>  drivers/video/fbdev/au1200fb.c        |  5 +++--
>  include/linux/dma-mapping.h           |  5 +++--
>  4 files changed, 23 insertions(+), 25 deletions(-)
> 
> diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt
> index 9070ff06b558..7e08c02b5393 100644
> --- a/Documentation/driver-model/devres.txt
> +++ b/Documentation/driver-model/devres.txt
> @@ -240,7 +240,7 @@ CLOCK
>  
>  DMA
>    dmam_alloc_coherent()
> -  dmam_alloc_noncoherent()
> +  dmam_alloc_attrs()
>    dmam_declare_coherent_memory()
>    dmam_free_coherent()
>    dmam_pool_create()
> diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c
> index 5940c9dace36..10e7c022e8cf 100644
> --- a/drivers/base/dma-mapping.c
> +++ b/drivers/base/dma-mapping.c
> @@ -22,20 +22,15 @@ struct dma_devres {
>  	size_t		size;
>  	void		*vaddr;
>  	dma_addr_t	dma_handle;
> +	unsigned long	attrs;
>  };
>  
> -static void dmam_coherent_release(struct device *dev, void *res)
> +static void dmam_release(struct device *dev, void *res)
>  {
>  	struct dma_devres *this = res;
>  
> -	dma_free_coherent(dev, this->size, this->vaddr, this->dma_handle);
> -}
> -
> -static void dmam_noncoherent_release(struct device *dev, void *res)
> -{
> -	struct dma_devres *this = res;
> -
> -	dma_free_noncoherent(dev, this->size, this->vaddr, this->dma_handle);
> +	dma_free_attrs(dev, this->size, this->vaddr, this->dma_handle,
> +			this->attrs);
>  }
>  
>  static int dmam_match(struct device *dev, void *res, void *match_data)
> @@ -69,7 +64,7 @@ void *dmam_alloc_coherent(struct device *dev, size_t size,
>  	struct dma_devres *dr;
>  	void *vaddr;
>  
> -	dr = devres_alloc(dmam_coherent_release, sizeof(*dr), gfp);
> +	dr = devres_alloc(dmam_release, sizeof(*dr), gfp);
>  	if (!dr)
>  		return NULL;
>  
> @@ -104,35 +99,35 @@ void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
>  	struct dma_devres match_data = { size, vaddr, dma_handle };
>  
>  	dma_free_coherent(dev, size, vaddr, dma_handle);
> -	WARN_ON(devres_destroy(dev, dmam_coherent_release, dmam_match,
> -			       &match_data));
> +	WARN_ON(devres_destroy(dev, dmam_release, dmam_match, &match_data));
>  }
>  EXPORT_SYMBOL(dmam_free_coherent);
>  
>  /**
> - * dmam_alloc_non_coherent - Managed dma_alloc_noncoherent()
> + * dmam_alloc_attrs - Managed dma_alloc_attrs()
>   * @dev: Device to allocate non_coherent memory for
>   * @size: Size of allocation
>   * @dma_handle: Out argument for allocated DMA handle
>   * @gfp: Allocation flags
> + * @attrs: Flags in the DMA_ATTR_* namespace.
>   *
> - * Managed dma_alloc_noncoherent().  Memory allocated using this
> - * function will be automatically released on driver detach.
> + * Managed dma_alloc_attrs().  Memory allocated using this function will be
> + * automatically released on driver detach.
>   *
>   * RETURNS:
>   * Pointer to allocated memory on success, NULL on failure.
>   */
> -void *dmam_alloc_noncoherent(struct device *dev, size_t size,
> -			     dma_addr_t *dma_handle, gfp_t gfp)
> +void *dmam_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
> +		gfp_t gfp, unsigned long attrs)
>  {
>  	struct dma_devres *dr;
>  	void *vaddr;
>  
> -	dr = devres_alloc(dmam_noncoherent_release, sizeof(*dr), gfp);
> +	dr = devres_alloc(dmam_release, sizeof(*dr), gfp);
>  	if (!dr)
>  		return NULL;
>  
> -	vaddr = dma_alloc_noncoherent(dev, size, dma_handle, gfp);
> +	vaddr = dma_alloc_attrs(dev, size, dma_handle, gfp, attrs);
>  	if (!vaddr) {
>  		devres_free(dr);
>  		return NULL;
> @@ -141,12 +136,13 @@ void *dmam_alloc_noncoherent(struct device *dev, size_t size,
>  	dr->vaddr = vaddr;
>  	dr->dma_handle = *dma_handle;
>  	dr->size = size;
> +	dr->attrs = attrs;
>  
>  	devres_add(dev, dr);
>  
>  	return vaddr;
>  }
> -EXPORT_SYMBOL(dmam_alloc_noncoherent);
> +EXPORT_SYMBOL(dmam_alloc_attrs);
>  
>  #ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT
>  
> diff --git a/drivers/video/fbdev/au1200fb.c b/drivers/video/fbdev/au1200fb.c
> index 6c2b2ca4a909..5f04b4096c42 100644
> --- a/drivers/video/fbdev/au1200fb.c
> +++ b/drivers/video/fbdev/au1200fb.c
> @@ -1694,9 +1694,10 @@ static int au1200fb_drv_probe(struct platform_device *dev)
>  		/* Allocate the framebuffer to the maximum screen size */
>  		fbdev->fb_len = (win->w[plane].xres * win->w[plane].yres * bpp) / 8;
>  
> -		fbdev->fb_mem = dmam_alloc_noncoherent(&dev->dev,
> +		fbdev->fb_mem = dmam_alloc_attrs(&dev->dev,
>  				PAGE_ALIGN(fbdev->fb_len),
> -				&fbdev->fb_phys, GFP_KERNEL);
> +				&fbdev->fb_phys, GFP_KERNEL,
> +				DMA_ATTR_NON_CONSISTENT);
>  		if (!fbdev->fb_mem) {
>  			print_err("fail to allocate frambuffer (size: %dK))",
>  				  fbdev->fb_len / 1024);
> diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
> index 830ec5f06a4f..6cdf5634906d 100644
> --- a/include/linux/dma-mapping.h
> +++ b/include/linux/dma-mapping.h
> @@ -747,8 +747,9 @@ extern void *dmam_alloc_coherent(struct device *dev, size_t size,
>  				 dma_addr_t *dma_handle, gfp_t gfp);
>  extern void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
>  			       dma_addr_t dma_handle);
> -extern void *dmam_alloc_noncoherent(struct device *dev, size_t size,
> -				    dma_addr_t *dma_handle, gfp_t gfp);
> +extern void *dmam_alloc_attrs(struct device *dev, size_t size,
> +			      dma_addr_t *dma_handle, gfp_t gfp,
> +			      unsigned long attrs);
>  #ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT
>  extern int dmam_declare_coherent_memory(struct device *dev,
>  					phys_addr_t phys_addr,
> -- 
> 2.11.0
> 
---end quoted text---