From ba9cc453c400049f632d4eb2f2835e2f96654ddc Mon Sep 17 00:00:00 2001
From: Jisheng Zhang <jszhang@marvell.com>
Date: Fri, 11 Sep 2015 08:49:47 +0100
Subject: [PATCH] arm64: dma-mapping: check whether cma area is initialized or
 not

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.

Arm has done this by commit e464ef16c4f0 ("arm: dma-mapping: add
checking cma area initialized"), also do this for arm64.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
---
 arch/arm64/mm/dma-mapping.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index 0bcc4bc94b4a..99224dcebdc5 100644
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -100,7 +100,7 @@ static void *__dma_alloc_coherent(struct device *dev, size_t size,
 	if (IS_ENABLED(CONFIG_ZONE_DMA) &&
 	    dev->coherent_dma_mask <= DMA_BIT_MASK(32))
 		flags |= GFP_DMA;
-	if (IS_ENABLED(CONFIG_DMA_CMA) && (flags & __GFP_WAIT)) {
+	if (dev_get_cma_area(dev) && (flags & __GFP_WAIT)) {
 		struct page *page;
 		void *addr;
 
-- 
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