If CMA is turned on and CMA size is set to zero, kernel should behave as if CMA was not enabled at compile time. Every dma allocation should check existence of cma area before requesting memory. Signed-off-by: Gioh Kim <gioh.kim@xxxxxxx> Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Acked-by: Michal Nazarewicz <mina86@xxxxxxxxxx> --- arch/arm/mm/dma-mapping.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 18e98df..9173a13 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -390,12 +390,13 @@ static int __init atomic_pool_init(void) if (!pages) goto no_pages; - if (IS_ENABLED(CONFIG_DMA_CMA)) + if (dev_get_cma_area(NULL)) ptr = __alloc_from_contiguous(NULL, pool->size, prot, &page, atomic_pool_init); else ptr = __alloc_remap_buffer(NULL, pool->size, gfp, prot, &page, atomic_pool_init); + if (ptr) { int i; @@ -701,7 +702,7 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, addr = __alloc_simple_buffer(dev, size, gfp, &page); else if (!(gfp & __GFP_WAIT)) addr = __alloc_from_pool(size, &page); - else if (!IS_ENABLED(CONFIG_DMA_CMA)) + else if (!dev_get_cma_area(dev)) addr = __alloc_remap_buffer(dev, size, gfp, prot, &page, caller); else addr = __alloc_from_contiguous(dev, size, prot, &page, caller); @@ -790,7 +791,7 @@ static void __arm_dma_free(struct device *dev, size_t size, void *cpu_addr, __dma_free_buffer(page, size); } else if (__free_from_pool(cpu_addr, size)) { return; - } else if (!IS_ENABLED(CONFIG_DMA_CMA)) { + } else if (!dev_get_cma_area(dev)) { __dma_free_remap(cpu_addr, size); __dma_free_buffer(page, size); } else { -- 1.7.9.5 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>