From 9406a49fd1f4379409ed87b29fdaa259b0441912 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 23 Aug 2018 09:39:38 +0200 Subject: dma-mapping: support non-coherent devices in dma_common_get_sgtable We can use the arch_dma_coherent_to_pfn hook to provide a ->get_sgtable implementation. Note that this isn't an endorsement of this interface (which is a horrible bad idea), but it is required to move arm64 over to the generic code without a loss of functionality. Signed-off-by: Christoph Hellwig --- kernel/dma/mapping.c | 23 ++++++++++++++++------- 1 file changed, 16 insertions(+), 7 deletions(-) (limited to 'kernel/dma') diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index 42fd73aca305..58dec7a92b7b 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -202,17 +202,26 @@ EXPORT_SYMBOL(dmam_release_declared_memory); * Create scatter-list for the already allocated DMA buffer. */ int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt, - void *cpu_addr, dma_addr_t handle, size_t size) + void *cpu_addr, dma_addr_t dma_addr, size_t size, + unsigned long attrs) { - struct page *page = virt_to_page(cpu_addr); + struct page *page; int ret; - ret = sg_alloc_table(sgt, 1, GFP_KERNEL); - if (unlikely(ret)) - return ret; + if (!dev_is_dma_coherent(dev)) { + if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_COHERENT_TO_PFN)) + return -ENXIO; - sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0); - return 0; + page = pfn_to_page(arch_dma_coherent_to_pfn(dev, cpu_addr, + dma_addr)); + } else { + page = virt_to_page(cpu_addr); + } + + ret = sg_alloc_table(sgt, 1, GFP_KERNEL); + if (!ret) + sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0); + return ret; } EXPORT_SYMBOL(dma_common_get_sgtable); -- cgit v1.2.3-59-g8ed1b