diff options
Diffstat (limited to 'kernel/dma/direct.c')
| -rw-r--r-- | kernel/dma/direct.c | 121 |
1 files changed, 115 insertions, 6 deletions
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index de87b0282e74..09e85f6aa4ba 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -1,13 +1,15 @@ // SPDX-License-Identifier: GPL-2.0 /* - * DMA operations that map physical memory directly without using an IOMMU or - * flushing caches. + * Copyright (C) 2018 Christoph Hellwig. + * + * DMA operations that map physical memory directly without using an IOMMU. */ #include <linux/export.h> #include <linux/mm.h> #include <linux/dma-direct.h> #include <linux/scatterlist.h> #include <linux/dma-contiguous.h> +#include <linux/dma-noncoherent.h> #include <linux/pfn.h> #include <linux/set_memory.h> @@ -58,8 +60,8 @@ static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size) return addr + size - 1 <= dev->coherent_dma_mask; } -void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, - gfp_t gfp, unsigned long attrs) +void *dma_direct_alloc_pages(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs) { unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT; int page_order = get_order(size); @@ -124,7 +126,7 @@ again: * NOTE: this function must never look at the dma_addr argument, because we want * to be able to use it as a helper for iommu implementations as well. */ -void dma_direct_free(struct device *dev, size_t size, void *cpu_addr, +void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs) { unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT; @@ -136,14 +138,106 @@ void dma_direct_free(struct device *dev, size_t size, void *cpu_addr, free_pages((unsigned long)cpu_addr, page_order); } +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)) + return arch_dma_alloc(dev, size, dma_handle, gfp, attrs); + return dma_direct_alloc_pages(dev, size, dma_handle, gfp, attrs); +} + +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)) + arch_dma_free(dev, size, cpu_addr, dma_addr, attrs); + else + dma_direct_free_pages(dev, size, cpu_addr, dma_addr, attrs); +} + +static int dma_direct_mmap(struct device *dev, struct vm_area_struct *vma, + void *cpu_addr, dma_addr_t dma_addr, size_t size, + unsigned long attrs) +{ + if (!dev_is_dma_coherent(dev) && + IS_ENABLED(CONFIG_DMA_NONCOHERENT_MMAP)) + return arch_dma_mmap(dev, vma, cpu_addr, dma_addr, size, attrs); + return dma_common_mmap(dev, vma, cpu_addr, dma_addr, size); +} + +static void dma_direct_sync_single_for_device(struct device *dev, + dma_addr_t addr, size_t size, enum dma_data_direction dir) +{ + if (dev_is_dma_coherent(dev)) + return; + arch_sync_dma_for_device(dev, dma_to_phys(dev, addr), size, dir); +} + +static void dma_direct_sync_sg_for_device(struct device *dev, + struct scatterlist *sgl, int nents, enum dma_data_direction dir) +{ + struct scatterlist *sg; + int i; + + if (dev_is_dma_coherent(dev)) + return; + + for_each_sg(sgl, sg, nents, i) + arch_sync_dma_for_device(dev, sg_phys(sg), sg->length, dir); +} + +#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \ + defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL) +static void dma_direct_sync_single_for_cpu(struct device *dev, + dma_addr_t addr, size_t size, enum dma_data_direction dir) +{ + if (dev_is_dma_coherent(dev)) + return; + arch_sync_dma_for_cpu(dev, dma_to_phys(dev, addr), size, dir); + arch_sync_dma_for_cpu_all(dev); +} + +static void dma_direct_sync_sg_for_cpu(struct device *dev, + struct scatterlist *sgl, int nents, enum dma_data_direction dir) +{ + struct scatterlist *sg; + int i; + + if (dev_is_dma_coherent(dev)) + return; + + for_each_sg(sgl, sg, nents, i) + arch_sync_dma_for_cpu(dev, sg_phys(sg), sg->length, dir); + arch_sync_dma_for_cpu_all(dev); +} + +static void dma_direct_unmap_page(struct device *dev, dma_addr_t addr, + size_t size, enum dma_data_direction dir, unsigned long attrs) +{ + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + dma_direct_sync_single_for_cpu(dev, addr, size, dir); +} + +static void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sgl, + int nents, enum dma_data_direction dir, unsigned long attrs) +{ + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + dma_direct_sync_sg_for_cpu(dev, sgl, nents, dir); +} +#endif + dma_addr_t dma_direct_map_page(struct device *dev, struct page *page, unsigned long offset, size_t size, enum dma_data_direction dir, unsigned long attrs) { - dma_addr_t dma_addr = phys_to_dma(dev, page_to_phys(page)) + offset; + phys_addr_t phys = page_to_phys(page) + offset; + dma_addr_t dma_addr = phys_to_dma(dev, phys); if (!check_addr(dev, dma_addr, size, __func__)) return DIRECT_MAPPING_ERROR; + + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + dma_direct_sync_single_for_device(dev, dma_addr, size, dir); return dma_addr; } @@ -162,6 +256,8 @@ int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents, sg_dma_len(sg) = sg->length; } + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + dma_direct_sync_sg_for_device(dev, sgl, nents, dir); return nents; } @@ -197,9 +293,22 @@ int dma_direct_mapping_error(struct device *dev, dma_addr_t dma_addr) const struct dma_map_ops dma_direct_ops = { .alloc = dma_direct_alloc, .free = dma_direct_free, + .mmap = dma_direct_mmap, .map_page = dma_direct_map_page, .map_sg = dma_direct_map_sg, +#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) + .sync_single_for_device = dma_direct_sync_single_for_device, + .sync_sg_for_device = dma_direct_sync_sg_for_device, +#endif +#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \ + defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL) + .sync_single_for_cpu = dma_direct_sync_single_for_cpu, + .sync_sg_for_cpu = dma_direct_sync_sg_for_cpu, + .unmap_page = dma_direct_unmap_page, + .unmap_sg = dma_direct_unmap_sg, +#endif .dma_supported = dma_direct_supported, .mapping_error = dma_direct_mapping_error, + .cache_sync = arch_dma_cache_sync, }; EXPORT_SYMBOL(dma_direct_ops); |