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

From: Christoph Hellwig
Date: Mon Jun 26 2017 - 03:08:01 EST


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@xxxxxx>
> ---
> 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---