[v4 3/4] ARM: dma-mapping: Introduce __atomic_get_pages() for __iommu_get_pages()
From: Hiroshi Doyu <hidden>
Date: 2012-08-28 05:15:31
Also in:
linux-arm-kernel, linux-mm, lkml
Subsystem:
arm port, the rest · Maintainers:
Russell King, Linus Torvalds
Support atomic allocation in __iommu_get_pages(). Signed-off-by: Hiroshi Doyu <redacted> --- arch/arm/mm/dma-mapping.c | 12 ++++++++++++ 1 files changed, 12 insertions(+), 0 deletions(-)
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index a62f552..4ef2d7b 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c@@ -503,6 +503,15 @@ static void *__alloc_from_pool(size_t size, struct page **ret_page) return ptr; } +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 bool __in_atomic_pool(void *start, size_t size) { struct dma_pool *pool = &atomic_pool;
@@ -1288,6 +1297,9 @@ 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;
--
1.7.5.4