On 14.06.19 16:44, Christoph Hellwig wrote:
> Only call into arch_dma_alloc if we require an uncached mapping,
> and remove the parisc code manually doing normal cached
> DMA_ATTR_NON_CONSISTENT allocations.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Acked-by: Helge Deller <deller@xxxxxx> # parisc
Boot-tested 32-bit kernel on PCX-L and PCX-W2 machines (although
the patches don't cleanly apply any longer against git head).
Helge
> ---
> arch/parisc/kernel/pci-dma.c | 48 ++++++++++--------------------------
> kernel/dma/direct.c | 4 +--
> 2 files changed, 15 insertions(+), 37 deletions(-)
>
> diff --git a/arch/parisc/kernel/pci-dma.c b/arch/parisc/kernel/pci-dma.c
> index 239162355b58..ca35d9a76e50 100644
> --- a/arch/parisc/kernel/pci-dma.c
> +++ b/arch/parisc/kernel/pci-dma.c
> @@ -394,17 +394,20 @@ pcxl_dma_init(void)
>
> __initcall(pcxl_dma_init);
>
> -static void *pcxl_dma_alloc(struct device *dev, size_t size,
> - dma_addr_t *dma_handle, gfp_t flag, unsigned long attrs)
> +void *arch_dma_alloc(struct device *dev, size_t size,
> + dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
> {
> unsigned long vaddr;
> unsigned long paddr;
> int order;
>
> + if (boot_cpu_data.cpu_type != pcxl2 && boot_cpu_data.cpu_type != pcxl)
> + return NULL;
> +
> order = get_order(size);
> size = 1 << (order + PAGE_SHIFT);
> vaddr = pcxl_alloc_range(size);
> - paddr = __get_free_pages(flag | __GFP_ZERO, order);
> + paddr = __get_free_pages(gfp | __GFP_ZERO, order);
> flush_kernel_dcache_range(paddr, size);
> paddr = __pa(paddr);
> map_uncached_pages(vaddr, size, paddr);
> @@ -421,44 +424,19 @@ static void *pcxl_dma_alloc(struct device *dev, size_t size,
> return (void *)vaddr;
> }
>
> -static void *pcx_dma_alloc(struct device *dev, size_t size,
> - dma_addr_t *dma_handle, gfp_t flag, unsigned long attrs)
> -{
> - void *addr;
> -
> - if ((attrs & DMA_ATTR_NON_CONSISTENT) == 0)
> - return NULL;
> -
> - addr = (void *)__get_free_pages(flag | __GFP_ZERO, get_order(size));
> - if (addr)
> - *dma_handle = (dma_addr_t)virt_to_phys(addr);
> -
> - return addr;
> -}
> -
> -void *arch_dma_alloc(struct device *dev, size_t size,
> - dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
> -{
> -
> - if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl)
> - return pcxl_dma_alloc(dev, size, dma_handle, gfp, attrs);
> - else
> - return pcx_dma_alloc(dev, size, dma_handle, gfp, attrs);
> -}
> -
> void arch_dma_free(struct device *dev, size_t size, void *vaddr,
> dma_addr_t dma_handle, unsigned long attrs)
> {
> int order = get_order(size);
>
> - if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl) {
> - size = 1 << (order + PAGE_SHIFT);
> - unmap_uncached_pages((unsigned long)vaddr, size);
> - pcxl_free_range((unsigned long)vaddr, size);
> + WARN_ON_ONCE(boot_cpu_data.cpu_type != pcxl2 &&
> + boot_cpu_data.cpu_type != pcxl);
>
> - vaddr = __va(dma_handle);
> - }
> - free_pages((unsigned long)vaddr, get_order(size));
> + size = 1 << (order + PAGE_SHIFT);
> + unmap_uncached_pages((unsigned long)vaddr, size);
> + pcxl_free_range((unsigned long)vaddr, size);
> +
> + free_pages((unsigned long)__va(dma_handle), order);
> }
>
> void arch_sync_dma_for_device(struct device *dev, phys_addr_t paddr,
> diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
> index c2893713bf80..fc354f4f490b 100644
> --- a/kernel/dma/direct.c
> +++ b/kernel/dma/direct.c
> @@ -191,7 +191,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
> dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
> {
> if (!IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) &&
> - !dev_is_dma_coherent(dev))
> + dma_alloc_need_uncached(dev, attrs))
> return arch_dma_alloc(dev, size, dma_handle, gfp, attrs);
> return dma_direct_alloc_pages(dev, size, dma_handle, gfp, attrs);
> }
> @@ -200,7 +200,7 @@ void dma_direct_free(struct device *dev, size_t size,
> void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs)
> {
> if (!IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) &&
> - !dev_is_dma_coherent(dev))
> + dma_alloc_need_uncached(dev, attrs))
> arch_dma_free(dev, size, cpu_addr, dma_addr, attrs);
> else
> dma_direct_free_pages(dev, size, cpu_addr, dma_addr, attrs);
>
