diff options
Diffstat (limited to 'kernel/dma')
| -rw-r--r-- | kernel/dma/Kconfig | 12 | ||||
| -rw-r--r-- | kernel/dma/direct.c | 59 | ||||
| -rw-r--r-- | kernel/dma/mapping.c | 45 | ||||
| -rw-r--r-- | kernel/dma/remap.c | 6 |
4 files changed, 75 insertions, 47 deletions
diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig index 73c5c2b8e824..4c103a24e380 100644 --- a/kernel/dma/Kconfig +++ b/kernel/dma/Kconfig @@ -51,9 +51,6 @@ config ARCH_HAS_SYNC_DMA_FOR_CPU_ALL config ARCH_HAS_DMA_PREP_COHERENT bool -config ARCH_HAS_DMA_COHERENT_TO_PFN - bool - config ARCH_HAS_FORCE_DMA_UNENCRYPTED bool @@ -68,9 +65,18 @@ config SWIOTLB bool select NEED_DMA_MAP_STATE +# +# Should be selected if we can mmap non-coherent mappings to userspace. +# The only thing that is really required is a way to set an uncached bit +# in the pagetables +# +config DMA_NONCOHERENT_MMAP + bool + config DMA_REMAP depends on MMU select GENERIC_ALLOCATOR + select DMA_NONCOHERENT_MMAP bool config DMA_DIRECT_REMAP diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 724c282dd943..58beaa9ddd27 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -43,6 +43,12 @@ static inline dma_addr_t phys_to_dma_direct(struct device *dev, return phys_to_dma(dev, phys); } +static inline struct page *dma_direct_to_page(struct device *dev, + dma_addr_t dma_addr) +{ + return pfn_to_page(PHYS_PFN(dma_to_phys(dev, dma_addr))); +} + u64 dma_direct_get_required_mask(struct device *dev) { u64 max_dma = phys_to_dma_direct(dev, (max_pfn - 1) << PAGE_SHIFT); @@ -379,6 +385,59 @@ dma_addr_t dma_direct_map_resource(struct device *dev, phys_addr_t paddr, } EXPORT_SYMBOL(dma_direct_map_resource); +int dma_direct_get_sgtable(struct device *dev, struct sg_table *sgt, + void *cpu_addr, dma_addr_t dma_addr, size_t size, + unsigned long attrs) +{ + struct page *page = dma_direct_to_page(dev, dma_addr); + int ret; + + ret = sg_alloc_table(sgt, 1, GFP_KERNEL); + if (!ret) + sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0); + return ret; +} + +#ifdef CONFIG_MMU +bool dma_direct_can_mmap(struct device *dev) +{ + return dev_is_dma_coherent(dev) || + IS_ENABLED(CONFIG_DMA_NONCOHERENT_MMAP); +} + +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) +{ + unsigned long user_count = vma_pages(vma); + unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT; + unsigned long pfn = PHYS_PFN(dma_to_phys(dev, dma_addr)); + int ret = -ENXIO; + + vma->vm_page_prot = dma_pgprot(dev, vma->vm_page_prot, attrs); + + if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret)) + return ret; + + if (vma->vm_pgoff >= count || user_count > count - vma->vm_pgoff) + return -ENXIO; + return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff, + user_count << PAGE_SHIFT, vma->vm_page_prot); +} +#else /* CONFIG_MMU */ +bool dma_direct_can_mmap(struct device *dev) +{ + return false; +} + +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) +{ + return -ENXIO; +} +#endif /* CONFIG_MMU */ + /* * Because 32-bit DMA masks are so common we expect every architecture to be * able to satisfy them - either by not supporting more physical memory, or by diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index d9334f31a5af..12ff766ec1fa 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -112,24 +112,9 @@ int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt, void *cpu_addr, dma_addr_t dma_addr, size_t size, unsigned long attrs) { - struct page *page; + struct page *page = virt_to_page(cpu_addr); int ret; - if (!dev_is_dma_coherent(dev)) { - unsigned long pfn; - - if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_COHERENT_TO_PFN)) - return -ENXIO; - - /* If the PFN is not valid, we do not have a struct page */ - pfn = arch_dma_coherent_to_pfn(dev, cpu_addr, dma_addr); - if (!pfn_valid(pfn)) - return -ENXIO; - page = pfn_to_page(pfn); - } 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); @@ -154,7 +139,7 @@ int dma_get_sgtable_attrs(struct device *dev, struct sg_table *sgt, const struct dma_map_ops *ops = get_dma_ops(dev); if (dma_is_direct(ops)) - return dma_common_get_sgtable(dev, sgt, cpu_addr, dma_addr, + return dma_direct_get_sgtable(dev, sgt, cpu_addr, dma_addr, size, attrs); if (!ops->get_sgtable) return -ENXIO; @@ -192,7 +177,6 @@ int dma_common_mmap(struct device *dev, struct vm_area_struct *vma, unsigned long user_count = vma_pages(vma); unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT; unsigned long off = vma->vm_pgoff; - unsigned long pfn; int ret = -ENXIO; vma->vm_page_prot = dma_pgprot(dev, vma->vm_page_prot, attrs); @@ -203,19 +187,8 @@ int dma_common_mmap(struct device *dev, struct vm_area_struct *vma, if (off >= count || user_count > count - off) return -ENXIO; - if (!dev_is_dma_coherent(dev)) { - if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_COHERENT_TO_PFN)) - return -ENXIO; - - /* If the PFN is not valid, we do not have a struct page */ - pfn = arch_dma_coherent_to_pfn(dev, cpu_addr, dma_addr); - if (!pfn_valid(pfn)) - return -ENXIO; - } else { - pfn = page_to_pfn(virt_to_page(cpu_addr)); - } - - return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff, + return remap_pfn_range(vma, vma->vm_start, + page_to_pfn(virt_to_page(cpu_addr)) + vma->vm_pgoff, user_count << PAGE_SHIFT, vma->vm_page_prot); #else return -ENXIO; @@ -233,12 +206,8 @@ bool dma_can_mmap(struct device *dev) { const struct dma_map_ops *ops = get_dma_ops(dev); - if (dma_is_direct(ops)) { - return IS_ENABLED(CONFIG_MMU) && - (dev_is_dma_coherent(dev) || - IS_ENABLED(CONFIG_ARCH_HAS_DMA_COHERENT_TO_PFN)); - } - + if (dma_is_direct(ops)) + return dma_direct_can_mmap(dev); return ops->mmap != NULL; } EXPORT_SYMBOL_GPL(dma_can_mmap); @@ -263,7 +232,7 @@ int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma, const struct dma_map_ops *ops = get_dma_ops(dev); if (dma_is_direct(ops)) - return dma_common_mmap(dev, vma, cpu_addr, dma_addr, size, + return dma_direct_mmap(dev, vma, cpu_addr, dma_addr, size, attrs); if (!ops->mmap) return -ENXIO; diff --git a/kernel/dma/remap.c b/kernel/dma/remap.c index 90d5ce77c189..3c49499ee6b0 100644 --- a/kernel/dma/remap.c +++ b/kernel/dma/remap.c @@ -259,10 +259,4 @@ void arch_dma_free(struct device *dev, size_t size, void *vaddr, dma_free_contiguous(dev, page, size); } } - -long arch_dma_coherent_to_pfn(struct device *dev, void *cpu_addr, - dma_addr_t dma_addr) -{ - return __phys_to_pfn(dma_to_phys(dev, dma_addr)); -} #endif /* CONFIG_DMA_DIRECT_REMAP */ |