lkml.org 
[lkml]   [2008]   [Sep]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 4/5] x86: dma_alloc_coherent sets gfp flags properly
On Mon, Sep 08, 2008 at 06:10:13PM +0900, FUJITA Tomonori wrote:
> Non real IOMMU implemenations (which doesn't do virtual mappings,
> e.g. swiotlb, pci-nommu, etc) need to use proper gfp flags and
> dma_mask to allocate pages in their own dma_alloc_coherent()
> (allocated page need to be suitable for device's coherent_dma_mask).
>
> This patch makes dma_alloc_coherent do this job so that IOMMUs don't
> need to take care of it any more.
>
> Real IOMMU implemenataions can simply ignore the gfp flags.
>
> Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>

Acked-by: Joerg Roedel <joerg.roedel@amd.com>

> ---
> arch/x86/kernel/pci-nommu.c | 19 ++-----------------
> include/asm-x86/dma-mapping.h | 32 ++++++++++++++++++++++++++++----
> 2 files changed, 30 insertions(+), 21 deletions(-)
>
> diff --git a/arch/x86/kernel/pci-nommu.c b/arch/x86/kernel/pci-nommu.c
> index ada1c87..8e398b5 100644
> --- a/arch/x86/kernel/pci-nommu.c
> +++ b/arch/x86/kernel/pci-nommu.c
> @@ -80,26 +80,11 @@ nommu_alloc_coherent(struct device *hwdev, size_t size,
> int node;
> struct page *page;
>
> - gfp |= __GFP_ZERO;
> -
> - dma_mask = hwdev->coherent_dma_mask;
> - if (!dma_mask)
> - dma_mask = *(hwdev->dma_mask);
> + dma_mask = dma_alloc_coherent_mask(hwdev, gfp);
>
> - if (dma_mask < DMA_24BIT_MASK)
> - return NULL;
> + gfp |= __GFP_ZERO;
>
> node = dev_to_node(hwdev);
> -
> -#ifdef CONFIG_X86_64
> - if (dma_mask <= DMA_32BIT_MASK && !(gfp & GFP_DMA))
> - gfp |= GFP_DMA32;
> -#endif
> -
> - /* No alloc-free penalty for ISA devices */
> - if (dma_mask == DMA_24BIT_MASK)
> - gfp |= GFP_DMA;
> -
> again:
> page = alloc_pages_node(node, gfp, get_order(size));
> if (!page)
> diff --git a/include/asm-x86/dma-mapping.h b/include/asm-x86/dma-mapping.h
> index 9d6dcf4..a072ae6 100644
> --- a/include/asm-x86/dma-mapping.h
> +++ b/include/asm-x86/dma-mapping.h
> @@ -241,6 +241,29 @@ static inline int dma_get_cache_alignment(void)
> return boot_cpu_data.x86_clflush_size;
> }
>
> +static inline unsigned long dma_alloc_coherent_mask(struct device *dev,
> + gfp_t gfp)
> +{
> + unsigned long dma_mask = 0;
> +
> + dma_mask = dev->coherent_dma_mask;
> + if (!dma_mask)
> + dma_mask = (gfp & GFP_DMA) ? DMA_24BIT_MASK : DMA_32BIT_MASK;
> +
> + return dma_mask;
> +}
> +
> +static inline gfp_t dma_alloc_coherent_gfp_flags(struct device *dev, gfp_t gfp)
> +{
> + unsigned long dma_mask = dma_alloc_coherent_mask(dev, gfp);
> +
> +#ifdef CONFIG_X86_64
> + if (dma_mask <= DMA_32BIT_MASK && !(gfp & GFP_DMA))
> + gfp |= GFP_DMA32;
> +#endif
> + return gfp;
> +}
> +
> static inline void *
> dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle,
> gfp_t gfp)
> @@ -261,10 +284,11 @@ dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle,
> if (!dev->dma_mask)
> return NULL;
>
> - if (ops->alloc_coherent)
> - return ops->alloc_coherent(dev, size,
> - dma_handle, gfp);
> - return NULL;
> + if (!ops->alloc_coherent)
> + return NULL;
> +
> + return ops->alloc_coherent(dev, size, dma_handle,
> + dma_alloc_coherent_gfp_flags(dev, gfp));
> }
>
> static inline void dma_free_coherent(struct device *dev, size_t size,
> --
> 1.5.5.GIT
>
>

--
| AMD Saxony Limited Liability Company & Co. KG
Operating | Wilschdorfer Landstr. 101, 01109 Dresden, Germany
System | Register Court Dresden: HRA 4896
Research | General Partner authorized to represent:
Center | AMD Saxony LLC (Wilmington, Delaware, US)
| General Manager of AMD Saxony LLC: Dr. Hans-R. Deppe, Thomas McCoy


\
 
 \ /
  Last update: 2008-09-08 14:05    [from the cache]
©2003-2014 Jasper Spaans. hosted at Digital Ocean