diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/dma/contiguous.c | 56 | ||||
| -rw-r--r-- | kernel/dma/direct.c | 55 | ||||
| -rw-r--r-- | kernel/dma/mapping.c | 12 | ||||
| -rw-r--r-- | kernel/dma/remap.c | 16 |
4 files changed, 106 insertions, 33 deletions
diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c index b2a87905846d..bfc0c17f2a3d 100644 --- a/kernel/dma/contiguous.c +++ b/kernel/dma/contiguous.c @@ -214,6 +214,62 @@ bool dma_release_from_contiguous(struct device *dev, struct page *pages, return cma_release(dev_get_cma_area(dev), pages, count); } +/** + * dma_alloc_contiguous() - allocate contiguous pages + * @dev: Pointer to device for which the allocation is performed. + * @size: Requested allocation size. + * @gfp: Allocation flags. + * + * This function allocates contiguous memory buffer for specified device. It + * first tries to use device specific contiguous memory area if available or + * the default global one, then tries a fallback allocation of normal pages. + * + * Note that it byapss one-page size of allocations from the global area as + * the addresses within one page are always contiguous, so there is no need + * to waste CMA pages for that kind; it also helps reduce fragmentations. + */ +struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp) +{ + int node = dev ? dev_to_node(dev) : NUMA_NO_NODE; + size_t count = PAGE_ALIGN(size) >> PAGE_SHIFT; + size_t align = get_order(PAGE_ALIGN(size)); + struct page *page = NULL; + struct cma *cma = NULL; + + if (dev && dev->cma_area) + cma = dev->cma_area; + else if (count > 1) + cma = dma_contiguous_default_area; + + /* CMA can be used only in the context which permits sleeping */ + if (cma && gfpflags_allow_blocking(gfp)) { + align = min_t(size_t, align, CONFIG_CMA_ALIGNMENT); + page = cma_alloc(cma, count, align, gfp & __GFP_NOWARN); + } + + /* Fallback allocation of normal pages */ + if (!page) + page = alloc_pages_node(node, gfp, align); + return page; +} + +/** + * dma_free_contiguous() - release allocated pages + * @dev: Pointer to device for which the pages were allocated. + * @page: Pointer to the allocated pages. + * @size: Size of allocated pages. + * + * This function releases memory allocated by dma_alloc_contiguous(). As the + * cma_release returns false when provided pages do not belong to contiguous + * area and true otherwise, this function then does a fallback __free_pages() + * upon a false-return. + */ +void dma_free_contiguous(struct device *dev, struct page *page, size_t size) +{ + if (!cma_release(dev_get_cma_area(dev), page, size >> PAGE_SHIFT)) + __free_pages(page, get_order(size)); +} + /* * Support for reserved memory regions defined in device tree */ diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 2c2772e9702a..b90e1aede743 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -96,8 +96,6 @@ static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size) struct page *__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); struct page *page = NULL; u64 phys_mask; @@ -109,20 +107,9 @@ struct page *__dma_direct_alloc_pages(struct device *dev, size_t size, gfp |= __dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask, &phys_mask); again: - /* CMA can be used only in the context which permits sleeping */ - if (gfpflags_allow_blocking(gfp)) { - page = dma_alloc_from_contiguous(dev, count, page_order, - gfp & __GFP_NOWARN); - if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) { - dma_release_from_contiguous(dev, page, count); - page = NULL; - } - } - if (!page) - page = alloc_pages_node(dev_to_node(dev), gfp, page_order); - + page = dma_alloc_contiguous(dev, size, gfp); if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) { - __free_pages(page, page_order); + dma_free_contiguous(dev, page, size); page = NULL; if (IS_ENABLED(CONFIG_ZONE_DMA32) && @@ -151,10 +138,18 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size, if (!page) return NULL; + if (attrs & DMA_ATTR_NO_KERNEL_MAPPING) { + /* remove any dirty cache lines on the kernel alias */ + if (!PageHighMem(page)) + arch_dma_prep_coherent(page, size); + /* return the page pointer as the opaque cookie */ + return page; + } + if (PageHighMem(page)) { /* * Depending on the cma= arguments and per-arch setup - * dma_alloc_from_contiguous could return highmem pages. + * dma_alloc_contiguous could return highmem pages. * Without remapping there is no way to return them here, * so log an error and fail. */ @@ -171,15 +166,19 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size, *dma_handle = phys_to_dma(dev, page_to_phys(page)); } memset(ret, 0, size); + + if (IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) && + dma_alloc_need_uncached(dev, attrs)) { + arch_dma_prep_coherent(page, size); + ret = uncached_kernel_address(ret); + } + return ret; } void __dma_direct_free_pages(struct device *dev, size_t size, struct page *page) { - unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT; - - if (!dma_release_from_contiguous(dev, page, count)) - __free_pages(page, get_order(size)); + dma_free_contiguous(dev, page, size); } void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr, @@ -187,15 +186,26 @@ void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr, { unsigned int page_order = get_order(size); + if (attrs & DMA_ATTR_NO_KERNEL_MAPPING) { + /* cpu_addr is a struct page cookie, not a kernel address */ + __dma_direct_free_pages(dev, size, cpu_addr); + return; + } + if (force_dma_unencrypted()) set_memory_encrypted((unsigned long)cpu_addr, 1 << page_order); + + if (IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) && + dma_alloc_need_uncached(dev, attrs)) + cpu_addr = cached_kernel_address(cpu_addr); __dma_direct_free_pages(dev, size, virt_to_page(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 (!IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) && + 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); } @@ -203,7 +213,8 @@ 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 (!IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) && + 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); diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index f7afdadb6770..1f628e7ac709 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -317,6 +317,12 @@ void arch_dma_set_mask(struct device *dev, u64 mask); int dma_set_mask(struct device *dev, u64 mask) { + /* + * Truncate the mask to the actually supported dma_addr_t width to + * avoid generating unsupportable addresses. + */ + mask = (dma_addr_t)mask; + if (!dev->dma_mask || !dma_supported(dev, mask)) return -EIO; @@ -330,6 +336,12 @@ EXPORT_SYMBOL(dma_set_mask); #ifndef CONFIG_ARCH_HAS_DMA_SET_COHERENT_MASK int dma_set_coherent_mask(struct device *dev, u64 mask) { + /* + * Truncate the mask to the actually supported dma_addr_t width to + * avoid generating unsupportable addresses. + */ + mask = (dma_addr_t)mask; + if (!dma_supported(dev, mask)) return -EIO; diff --git a/kernel/dma/remap.c b/kernel/dma/remap.c index 7a723194ecbe..a594aec07882 100644 --- a/kernel/dma/remap.c +++ b/kernel/dma/remap.c @@ -158,6 +158,9 @@ out: bool dma_in_atomic_pool(void *start, size_t size) { + if (unlikely(!atomic_pool)) + return false; + return addr_in_gen_pool(atomic_pool, (unsigned long)start, size); } @@ -199,8 +202,7 @@ void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, size = PAGE_ALIGN(size); - if (!gfpflags_allow_blocking(flags) && - !(attrs & DMA_ATTR_NO_KERNEL_MAPPING)) { + if (!gfpflags_allow_blocking(flags)) { ret = dma_alloc_from_pool(size, &page, flags); if (!ret) return NULL; @@ -214,11 +216,6 @@ void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, /* remove any dirty cache lines on the kernel alias */ arch_dma_prep_coherent(page, size); - if (attrs & DMA_ATTR_NO_KERNEL_MAPPING) { - ret = page; /* opaque cookie */ - goto done; - } - /* create a coherent mapping */ ret = dma_common_contiguous_remap(page, size, VM_USERMAP, arch_dma_mmap_pgprot(dev, PAGE_KERNEL, attrs), @@ -237,10 +234,7 @@ done: void arch_dma_free(struct device *dev, size_t size, void *vaddr, dma_addr_t dma_handle, unsigned long attrs) { - if (attrs & DMA_ATTR_NO_KERNEL_MAPPING) { - /* vaddr is a struct page cookie, not a kernel address */ - __dma_direct_free_pages(dev, size, vaddr); - } else if (!dma_free_from_pool(vaddr, PAGE_ALIGN(size))) { + if (!dma_free_from_pool(vaddr, PAGE_ALIGN(size))) { phys_addr_t phys = dma_to_phys(dev, dma_handle); struct page *page = pfn_to_page(__phys_to_pfn(phys)); |