If DMA_ATTR_NON_CONSISTENT is passed in the flags we can always just use the dma_direct_alloc_pages implementation given that the callers will take care of any cache maintainance on ownership transfers between the CPU and the device. Signed-off-by: Christoph Hellwig <hch@xxxxxx> --- arch/arc/mm/dma.c | 21 ++++++-------------- arch/mips/mm/dma-noncoherent.c | 5 ++--- arch/openrisc/kernel/dma.c | 23 +++++++++------------- arch/parisc/kernel/pci-dma.c | 35 ++++++++++++---------------------- kernel/dma/direct.c | 4 ++-- 5 files changed, 31 insertions(+), 57 deletions(-) diff --git a/arch/arc/mm/dma.c b/arch/arc/mm/dma.c index db203ff69ccf..135759d4ea8c 100644 --- a/arch/arc/mm/dma.c +++ b/arch/arc/mm/dma.c @@ -24,7 +24,6 @@ void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, struct page *page; phys_addr_t paddr; void *kvaddr; - bool need_coh = !(attrs & DMA_ATTR_NON_CONSISTENT); /* * __GFP_HIGHMEM flag is cleared by upper layer functions @@ -46,14 +45,10 @@ void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, * A coherent buffer needs MMU mapping to enforce non-cachability. * kvaddr is kernel Virtual address (0x7000_0000 based). */ - if (need_coh) { - kvaddr = ioremap_nocache(paddr, size); - if (kvaddr == NULL) { - __free_pages(page, order); - return NULL; - } - } else { - kvaddr = (void *)(u32)paddr; + kvaddr = ioremap_nocache(paddr, size); + if (kvaddr == NULL) { + __free_pages(page, order); + return NULL; } /* @@ -66,9 +61,7 @@ void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, * Currently flush_cache_vmap nukes the L1 cache completely which * will be optimized as a separate commit */ - if (need_coh) - dma_cache_wback_inv(paddr, size); - + dma_cache_wback_inv(paddr, size); return kvaddr; } @@ -78,9 +71,7 @@ void arch_dma_free(struct device *dev, size_t size, void *vaddr, phys_addr_t paddr = dma_handle; struct page *page = virt_to_page(paddr); - if (!(attrs & DMA_ATTR_NON_CONSISTENT)) - iounmap((void __force __iomem *)vaddr); - + iounmap((void __force __iomem *)vaddr); __free_pages(page, get_order(size)); } diff --git a/arch/mips/mm/dma-noncoherent.c b/arch/mips/mm/dma-noncoherent.c index cb38461391cb..7576cd7193ba 100644 --- a/arch/mips/mm/dma-noncoherent.c +++ b/arch/mips/mm/dma-noncoherent.c @@ -50,7 +50,7 @@ void *arch_dma_alloc(struct device *dev, size_t size, void *ret; ret = dma_direct_alloc_pages(dev, size, dma_handle, gfp, attrs); - if (ret && !(attrs & DMA_ATTR_NON_CONSISTENT)) { + if (ret) { dma_cache_wback_inv((unsigned long) ret, size); ret = (void *)UNCAC_ADDR(ret); } @@ -61,8 +61,7 @@ void *arch_dma_alloc(struct device *dev, size_t size, void arch_dma_free(struct device *dev, size_t size, void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs) { - if (!(attrs & DMA_ATTR_NON_CONSISTENT)) - cpu_addr = (void *)CAC_ADDR((unsigned long)cpu_addr); + cpu_addr = (void *)CAC_ADDR((unsigned long)cpu_addr); dma_direct_free_pages(dev, size, cpu_addr, dma_addr, attrs); } diff --git a/arch/openrisc/kernel/dma.c b/arch/openrisc/kernel/dma.c index 159336adfa2f..483adbb000bb 100644 --- a/arch/openrisc/kernel/dma.c +++ b/arch/openrisc/kernel/dma.c @@ -98,15 +98,13 @@ arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, va = (unsigned long)page; - if ((attrs & DMA_ATTR_NON_CONSISTENT) == 0) { - /* - * We need to iterate through the pages, clearing the dcache for - * them and setting the cache-inhibit bit. - */ - if (walk_page_range(va, va + size, &walk)) { - free_pages_exact(page, size); - return NULL; - } + /* + * We need to iterate through the pages, clearing the dcache for + * them and setting the cache-inhibit bit. + */ + if (walk_page_range(va, va + size, &walk)) { + free_pages_exact(page, size); + return NULL; } return (void *)va; @@ -122,11 +120,8 @@ arch_dma_free(struct device *dev, size_t size, void *vaddr, .mm = &init_mm }; - if ((attrs & DMA_ATTR_NON_CONSISTENT) == 0) { - /* walk_page_range shouldn't be able to fail here */ - WARN_ON(walk_page_range(va, va + size, &walk)); - } - + /* walk_page_range shouldn't be able to fail here */ + WARN_ON(walk_page_range(va, va + size, &walk)); free_pages_exact(vaddr, size); } diff --git a/arch/parisc/kernel/pci-dma.c b/arch/parisc/kernel/pci-dma.c index 04c48f1ef3fb..6780449e3e8b 100644 --- a/arch/parisc/kernel/pci-dma.c +++ b/arch/parisc/kernel/pci-dma.c @@ -421,29 +421,18 @@ 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) +static inline bool cpu_supports_coherent_area(void) { - void *addr; - - if ((attrs & DMA_ATTR_NON_CONSISTENT) == 0) - return NULL; - - addr = (void *)__get_free_pages(flag, get_order(size)); - if (addr) - *dma_handle = (dma_addr_t)virt_to_phys(addr); - - return addr; + return boot_cpu_data.cpu_type == pcxl2 || + boot_cpu_data.cpu_type == pcxl; } 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) + if (cpu_supports_coherent_area()) return pcxl_dma_alloc(dev, size, dma_handle, gfp, attrs); - else - return pcx_dma_alloc(dev, size, dma_handle, gfp, attrs); + return NULL; } void arch_dma_free(struct device *dev, size_t size, void *vaddr, @@ -451,14 +440,14 @@ void arch_dma_free(struct device *dev, size_t size, void *vaddr, { 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); + if (WARN_ON_ONCE(!cpu_supports_coherent_area())) + return; - 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), get_order(size)); } 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 308f88a750c8..4efe1188fd2e 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -206,7 +206,7 @@ void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr, void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs) { - if (!dev_is_dma_coherent(dev)) + if (!dev_is_dma_coherent(dev) && !(attrs & DMA_ATTR_NON_CONSISTENT)) return arch_dma_alloc(dev, size, dma_handle, gfp, attrs); return dma_direct_alloc_pages(dev, size, dma_handle, gfp, attrs); } @@ -214,7 +214,7 @@ void *dma_direct_alloc(struct device *dev, size_t size, void dma_direct_free(struct device *dev, size_t size, void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs) { - if (!dev_is_dma_coherent(dev)) + if (!dev_is_dma_coherent(dev) && !(attrs & DMA_ATTR_NON_CONSISTENT)) arch_dma_free(dev, size, cpu_addr, dma_addr, attrs); else dma_direct_free_pages(dev, size, cpu_addr, dma_addr, attrs); -- 2.19.2 _______________________________________________ linux-snps-arc mailing list linux-snps-arc@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/linux-snps-arc