diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index c5f9ae5dbd1ad04da804d68e475d3b4b230832f6..2f88d8d9770116014f7ff55e80d98c65fbb191ed 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -6,7 +6,7 @@ config ARM select HAVE_DMA_API_DEBUG select HAVE_IDE if PCI || ISA || PCMCIA select HAVE_DMA_ATTRS - select HAVE_DMA_CONTIGUOUS if (CPU_V6 || CPU_V6K || CPU_V7) + select HAVE_DMA_CONTIGUOUS if MMU select HAVE_MEMBLOCK select RTC_LIB select SYS_SUPPORTS_APM_EMULATION diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h index 2ae842df455180d3bcd445d339ecd332d3b36c4e..5c44dcb0987bd31418298f7932baaa5a82320477 100644 --- a/arch/arm/include/asm/dma-mapping.h +++ b/arch/arm/include/asm/dma-mapping.h @@ -202,6 +202,13 @@ static inline void dma_free_writecombine(struct device *dev, size_t size, return dma_free_attrs(dev, size, cpu_addr, dma_handle, &attrs); } +/* + * This can be called during early boot to increase the size of the atomic + * coherent DMA pool above the default value of 256KiB. It must be called + * before postcore_initcall. + */ +extern void __init init_dma_coherent_pool_size(unsigned long size); + /* * This can be called during boot to increase the size of the consistent * DMA region above it's default value of 2MB. It must be called before the diff --git a/arch/arm/mach-kirkwood/common.c b/arch/arm/mach-kirkwood/common.c index 3226077735b1d7104627f8f40307e84c97d4ca5b..1201191d7f1bb24c386df88f5fe4de14e172b006 100644 --- a/arch/arm/mach-kirkwood/common.c +++ b/arch/arm/mach-kirkwood/common.c @@ -517,6 +517,13 @@ void __init kirkwood_wdt_init(void) void __init kirkwood_init_early(void) { orion_time_set_base(TIMER_VIRT_BASE); + + /* + * Some Kirkwood devices allocate their coherent buffers from atomic + * context. Increase size of atomic coherent pool to make sure such + * the allocations won't fail. + */ + init_dma_coherent_pool_size(SZ_1M); } int kirkwood_tclk; diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 4e7d1182e8a3a59270073b5cb3b348e0bd690ef8..051204fc4617670321bfa5fa7c1f3621cb49a33c 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -267,17 +267,19 @@ static void __dma_free_remap(void *cpu_addr, size_t size) vunmap(cpu_addr); } +#define DEFAULT_DMA_COHERENT_POOL_SIZE SZ_256K + struct dma_pool { size_t size; spinlock_t lock; unsigned long *bitmap; unsigned long nr_pages; void *vaddr; - struct page *page; + struct page **pages; }; static struct dma_pool atomic_pool = { - .size = SZ_256K, + .size = DEFAULT_DMA_COHERENT_POOL_SIZE, }; static int __init early_coherent_pool(char *p) @@ -287,6 +289,21 @@ static int __init early_coherent_pool(char *p) } early_param("coherent_pool", early_coherent_pool); +void __init init_dma_coherent_pool_size(unsigned long size) +{ + /* + * Catch any attempt to set the pool size too late. + */ + BUG_ON(atomic_pool.vaddr); + + /* + * Set architecture specific coherent pool size only if + * it has not been changed by kernel command line parameter. + */ + if (atomic_pool.size == DEFAULT_DMA_COHERENT_POOL_SIZE) + atomic_pool.size = size; +} + /* * Initialise the coherent pool for atomic allocations. */ @@ -297,6 +314,7 @@ static int __init atomic_pool_init(void) unsigned long nr_pages = pool->size >> PAGE_SHIFT; unsigned long *bitmap; struct page *page; + struct page **pages; void *ptr; int bitmap_size = BITS_TO_LONGS(nr_pages) * sizeof(long); @@ -304,21 +322,31 @@ static int __init atomic_pool_init(void) if (!bitmap) goto no_bitmap; + pages = kzalloc(nr_pages * sizeof(struct page *), GFP_KERNEL); + if (!pages) + goto no_pages; + if (IS_ENABLED(CONFIG_CMA)) ptr = __alloc_from_contiguous(NULL, pool->size, prot, &page); else ptr = __alloc_remap_buffer(NULL, pool->size, GFP_KERNEL, prot, &page, NULL); if (ptr) { + int i; + + for (i = 0; i < nr_pages; i++) + pages[i] = page + i; + spin_lock_init(&pool->lock); pool->vaddr = ptr; - pool->page = page; + pool->pages = pages; pool->bitmap = bitmap; pool->nr_pages = nr_pages; pr_info("DMA: preallocated %u KiB pool for atomic coherent allocations\n", (unsigned)pool->size / 1024); return 0; } +no_pages: kfree(bitmap); no_bitmap: pr_err("DMA: failed to allocate %u KiB pool for atomic coherent allocation\n", @@ -443,27 +471,45 @@ static void *__alloc_from_pool(size_t size, struct page **ret_page) if (pageno < pool->nr_pages) { bitmap_set(pool->bitmap, pageno, count); ptr = pool->vaddr + PAGE_SIZE * pageno; - *ret_page = pool->page + pageno; + *ret_page = pool->pages[pageno]; + } else { + pr_err_once("ERROR: %u KiB atomic DMA coherent pool is too small!\n" + "Please increase it with coherent_pool= kernel parameter!\n", + (unsigned)pool->size / 1024); } spin_unlock_irqrestore(&pool->lock, flags); return ptr; } +static bool __in_atomic_pool(void *start, size_t size) +{ + struct dma_pool *pool = &atomic_pool; + void *end = start + size; + void *pool_start = pool->vaddr; + void *pool_end = pool->vaddr + pool->size; + + if (start < pool_start || start > pool_end) + return false; + + if (end <= pool_end) + return true; + + WARN(1, "Wrong coherent size(%p-%p) from atomic pool(%p-%p)\n", + start, end - 1, pool_start, pool_end - 1); + + return false; +} + static int __free_from_pool(void *start, size_t size) { struct dma_pool *pool = &atomic_pool; unsigned long pageno, count; unsigned long flags; - if (start < pool->vaddr || start > pool->vaddr + pool->size) + if (!__in_atomic_pool(start, size)) return 0; - if (start + size > pool->vaddr + pool->size) { - WARN(1, "freeing wrong coherent size from pool\n"); - return 0; - } - pageno = (start - pool->vaddr) >> PAGE_SHIFT; count = size >> PAGE_SHIFT; @@ -1090,10 +1136,22 @@ static int __iommu_remove_mapping(struct device *dev, dma_addr_t iova, size_t si return 0; } +static struct page **__atomic_get_pages(void *addr) +{ + struct dma_pool *pool = &atomic_pool; + struct page **pages = pool->pages; + int offs = (addr - pool->vaddr) >> PAGE_SHIFT; + + return pages + offs; +} + static struct page **__iommu_get_pages(void *cpu_addr, struct dma_attrs *attrs) { struct vm_struct *area; + if (__in_atomic_pool(cpu_addr, PAGE_SIZE)) + return __atomic_get_pages(cpu_addr); + if (dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs)) return cpu_addr; @@ -1103,6 +1161,34 @@ static struct page **__iommu_get_pages(void *cpu_addr, struct dma_attrs *attrs) return NULL; } +static void *__iommu_alloc_atomic(struct device *dev, size_t size, + dma_addr_t *handle) +{ + struct page *page; + void *addr; + + addr = __alloc_from_pool(size, &page); + if (!addr) + return NULL; + + *handle = __iommu_create_mapping(dev, &page, size); + if (*handle == DMA_ERROR_CODE) + goto err_mapping; + + return addr; + +err_mapping: + __free_from_pool(addr, size); + return NULL; +} + +static void __iommu_free_atomic(struct device *dev, struct page **pages, + dma_addr_t handle, size_t size) +{ + __iommu_remove_mapping(dev, handle, size); + __free_from_pool(page_address(pages[0]), size); +} + static void *arm_iommu_alloc_attrs(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp, struct dma_attrs *attrs) { @@ -1113,6 +1199,9 @@ static void *arm_iommu_alloc_attrs(struct device *dev, size_t size, *handle = DMA_ERROR_CODE; size = PAGE_ALIGN(size); + if (gfp & GFP_ATOMIC) + return __iommu_alloc_atomic(dev, size, handle); + pages = __iommu_alloc_buffer(dev, size, gfp); if (!pages) return NULL; @@ -1179,6 +1268,11 @@ void arm_iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr, return; } + if (__in_atomic_pool(cpu_addr, size)) { + __iommu_free_atomic(dev, pages, handle, size); + return; + } + if (!dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs)) { unmap_kernel_range((unsigned long)cpu_addr, size); vunmap(cpu_addr); diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c index 78efb0306a446027f7fce1019572902f5aaa805b..34d94c762a1e79415fc00b0fc59caf034a3e186a 100644 --- a/drivers/base/dma-contiguous.c +++ b/drivers/base/dma-contiguous.c @@ -250,7 +250,7 @@ int __init dma_declare_contiguous(struct device *dev, unsigned long size, return -EINVAL; /* Sanitise input arguments */ - alignment = PAGE_SIZE << max(MAX_ORDER, pageblock_order); + alignment = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order); base = ALIGN(base, alignment); size = ALIGN(size, alignment); limit &= ~(alignment - 1);