arm: dma-mapping: fallback allocation for cma failure

Thanks for your advise, Michal Nazarewicz.

Having discuss with Joonsoo, I'm adding fallback allocation after __alloc_from_contiguous(). The fallback allocation works if CMA kernel options is turned on but CMA size is zero.

Quoted 5 lines

Thanks for your advise, Michal Nazarewicz.

Having discuss with Joonsoo, I'm adding fallback allocation after __alloc_from_contiguous(). The fallback allocation works if CMA kernel options is turned on but CMA size is zero.

Hello, Gioh.

I also mentioned the case where devices have their specific cma_area. It means that this device needs memory with some contraint. Although I'm not familiar with DMA infrastructure, I think that we should handle this case.

How about below patch?

------------>8----------------

arch/arm/mm/dma-mapping.c +12 -6

index 6b00be1..4023434 100644
@@ -379,7 +379,7 @@ static int __init atomic_pool_init(void)
  	unsigned long *bitmap;
  	struct page *page;
  	struct page **pages;
-	void *ptr;
+	void *ptr = NULL;
  	int bitmap_size = BITS_TO_LONGS(nr_pages) * sizeof(long);
 
  	bitmap = kzalloc(bitmap_size, GFP_KERNEL);

@@ -393,7 +393,8 @@ static int __init atomic_pool_init(void)
  	if (IS_ENABLED(CONFIG_DMA_CMA))
  		ptr = __alloc_from_contiguous(NULL, pool->size, prot, &page,
  					      atomic_pool_init);
-	else
+
+	if (!ptr)
  		ptr = __alloc_remap_buffer(NULL, pool->size, gfp, prot, &page,
  					   atomic_pool_init);
  	if (ptr) {

@@ -701,10 +702,22 @@ 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))
-		addr = __alloc_remap_buffer(dev, size, gfp, prot, &page, caller);
-	else
-		addr = __alloc_from_contiguous(dev, size, prot, &page, caller);
+	else {
+		if (IS_ENABLED(CONFIG_DMA_CMA)) {
+			addr = __alloc_from_contiguous(dev, size, prot,
+							&page, caller);
+			/*
+			 * Device specific cma_area means that
+			 * this device needs memory with some contraint.
+			 * So, we can't fall through general remap allocation.
+			 */

That case, device-specific coherent memory allocation, is handled at dma_alloc_coherent in arm_dma_alloc. __dma_alloc handles only general coherent memory allocation.

I'm sorry missing mention about it.

Quoted 5 lines

That case, device-specific coherent memory allocation, is handled at dma_alloc_coherent in arm_dma_alloc. __dma_alloc handles only general coherent memory allocation.

I'm sorry missing mention about it.

Hello,

AFAIK, *coherent* memory allocation is different with *contiguous* memory allocation(CMA). So we need to handle the case I mentioned.

Thanks.

Quoted 5 lines · Gioh Kim

Thanks for your advise, Michal Nazarewicz.

Having discuss with Joonsoo, I'm adding fallback allocation after __alloc_from_contiguous(). The fallback allocation works if CMA kernel options is turned on but CMA size is zero.

Hello, Gioh.

I also mentioned the case where devices have their specific cma_area. It means that this device needs memory with some contraint. Although I'm not familiar with DMA infrastructure, I think that we should handle this case.

How about below patch?

------------>8----------------

arch/arm/mm/dma-mapping.c +9 -6

index 6b00be1..4023434 100644
@@ -379,7 +379,7 @@ static int __init atomic_pool_init(void)
 	unsigned long *bitmap;
 	struct page *page;
 	struct page **pages;
-	void *ptr;
+	void *ptr = NULL;
 	int bitmap_size = BITS_TO_LONGS(nr_pages) * sizeof(long);
 
 	bitmap = kzalloc(bitmap_size, GFP_KERNEL);

@@ -393,7 +393,8 @@ static int __init atomic_pool_init(void)
 	if (IS_ENABLED(CONFIG_DMA_CMA))
 		ptr = __alloc_from_contiguous(NULL, pool->size, prot, &page,
 					      atomic_pool_init);
-	else
+
+	if (!ptr)
 		ptr = __alloc_remap_buffer(NULL, pool->size, gfp, prot, &page,
 					   atomic_pool_init);
 	if (ptr) {

@@ -701,10 +702,22 @@ 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))
-		addr = __alloc_remap_buffer(dev, size, gfp, prot, &page, caller);
-	else
-		addr = __alloc_from_contiguous(dev, size, prot, &page, caller);
+	else {
+		if (IS_ENABLED(CONFIG_DMA_CMA)) {
+			addr = __alloc_from_contiguous(dev, size, prot,
+							&page, caller);
+			/*
+			 * Device specific cma_area means that

arch/arm/mm/dma-mapping.c +0 -0

 	if (addr)
 		*handle = pfn_to_dma(dev, page_to_pfn(page));

Quoted 61 lines · Gioh Kim

Quoted 5 lines

Thanks for your advise, Michal Nazarewicz.

Having discuss with Joonsoo, I'm adding fallback allocation after __alloc_from_contiguous(). The fallback allocation works if CMA kernel options is turned on but CMA size is zero.

Hello, Gioh.

I also mentioned the case where devices have their specific cma_area. It means that this device needs memory with some contraint. Although I'm not familiar with DMA infrastructure, I think that we should handle this case.

How about below patch?

------------>8----------------

arch/arm/mm/dma-mapping.c +16 -6

index 6b00be1..4023434 100644
@@ -379,7 +379,7 @@ static int __init atomic_pool_init(void)
  	unsigned long *bitmap;
  	struct page *page;
  	struct page **pages;
-	void *ptr;
+	void *ptr = NULL;
  	int bitmap_size = BITS_TO_LONGS(nr_pages) * sizeof(long);
 
  	bitmap = kzalloc(bitmap_size, GFP_KERNEL);

@@ -393,7 +393,8 @@ static int __init atomic_pool_init(void)
  	if (IS_ENABLED(CONFIG_DMA_CMA))
  		ptr = __alloc_from_contiguous(NULL, pool->size, prot, &page,
  					      atomic_pool_init);
-	else
+
+	if (!ptr)
  		ptr = __alloc_remap_buffer(NULL, pool->size, gfp, prot, &page,
  					   atomic_pool_init);
  	if (ptr) {

@@ -701,10 +702,22 @@ 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))
-		addr = __alloc_remap_buffer(dev, size, gfp, prot, &page, caller);
-	else
-		addr = __alloc_from_contiguous(dev, size, prot, &page, caller);
+	else {
+		if (IS_ENABLED(CONFIG_DMA_CMA)) {
+			addr = __alloc_from_contiguous(dev, size, prot,
+							&page, caller);
+			/*
+			 * Device specific cma_area means that
+			 * this device needs memory with some contraint.
+			 * So, we can't fall through general remap allocation.
+			 */
+			if (!addr && dev && dev->cma_area)
+				return NULL;
+		}
+

arch/arm/mm/dma-mapping.c static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, · line 720

Quoted 3 lines

arch/arm/mm/dma-mapping.c +3 -0

+		addr = __alloc_remap_buffer(dev, size, gfp, prot,
+							&page, caller);
+	}

__arm_dma_free will have to be changed to handle the fallback as well. But perhaps Marek is right and there should be no fallback for regular allocations? Than again, non-CMA allocation should be performed at least in the case of cma=0.

arch/arm/mm/dma-mapping.c static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, · line 723

Quoted 4 lines

arch/arm/mm/dma-mapping.c +0 -0

  	if (addr)
  		*handle = pfn_to_dma(dev, page_to_pfn(page));

Quoted 61 lines · Gioh Kim

Quoted 5 lines

Thanks for your advise, Michal Nazarewicz.

Having discuss with Joonsoo, I'm adding fallback allocation after __alloc_from_contiguous(). The fallback allocation works if CMA kernel options is turned on but CMA size is zero.

Hello, Gioh.

I also mentioned the case where devices have their specific cma_area. It means that this device needs memory with some contraint. Although I'm not familiar with DMA infrastructure, I think that we should handle this case.

How about below patch?

------------>8----------------

arch/arm/mm/dma-mapping.c +16 -6

index 6b00be1..4023434 100644
@@ -379,7 +379,7 @@ static int __init atomic_pool_init(void)
  	unsigned long *bitmap;
  	struct page *page;
  	struct page **pages;
-	void *ptr;
+	void *ptr = NULL;
  	int bitmap_size = BITS_TO_LONGS(nr_pages) * sizeof(long);
 
  	bitmap = kzalloc(bitmap_size, GFP_KERNEL);

@@ -393,7 +393,8 @@ static int __init atomic_pool_init(void)
  	if (IS_ENABLED(CONFIG_DMA_CMA))
  		ptr = __alloc_from_contiguous(NULL, pool->size, prot, &page,
  					      atomic_pool_init);
-	else
+
+	if (!ptr)
  		ptr = __alloc_remap_buffer(NULL, pool->size, gfp, prot, &page,
  					   atomic_pool_init);
  	if (ptr) {

@@ -701,10 +702,22 @@ 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))
-		addr = __alloc_remap_buffer(dev, size, gfp, prot, &page, caller);
-	else
-		addr = __alloc_from_contiguous(dev, size, prot, &page, caller);
+	else {
+		if (IS_ENABLED(CONFIG_DMA_CMA)) {
+			addr = __alloc_from_contiguous(dev, size, prot,
+							&page, caller);
+			/*
+			 * Device specific cma_area means that
+			 * this device needs memory with some contraint.
+			 * So, we can't fall through general remap allocation.
+			 */
+			if (!addr && dev && dev->cma_area)
+				return NULL;
+		}
+

arch/arm/mm/dma-mapping.c static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, · line 720

Quoted 3 lines

arch/arm/mm/dma-mapping.c +3 -0

+		addr = __alloc_remap_buffer(dev, size, gfp, prot,
+							&page, caller);
+	}

__arm_dma_free will have to be changed to handle the fallback as well. But perhaps Marek is right and there should be no fallback for regular allocations? Than again, non-CMA allocation should be performed at least in the case of cma=0.

Quoted 3 lines

arch/arm/mm/dma-mapping.c +0 -0

  	if (addr)
  		*handle = pfn_to_dma(dev, page_to_pfn(page));

Date: Tue, 20 May 2014 14:16:20 +0900
Subject: [PATCH] arm: dma-mapping: add checking cma area initialized

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 <[email protected]>

Signed-off-by Joonsoo Kim <[email protected]>

---
  arch/arm/mm/dma-mapping.c |   12 ++++++++----
  1 file changed, 8 insertions(+), 4 deletions(-)

arch/arm/mm/dma-mapping.c +0 -0

index 18e98df..61f7b93 100644

arch/arm/mm/dma-mapping.c +2 -0

                 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;
 

@@ -669,6 +670,7 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
         u64 mask = get_coherent_dma_mask(dev);
         struct page *page = NULL;
         void *addr;
+       struct cma *cma = dev_get_cma_area(dev);
 
  #ifdef CONFIG_DMA_API_DEBUG
         u64 limit = (mask + 1) & ~mask;

arch/arm/mm/dma-mapping.c +1 -0

                 addr = __alloc_remap_buffer(dev, size, gfp, prot, &page, caller);
         else
                 addr = __alloc_from_contiguous(dev, size, prot, &page, caller);

@@ -780,6 +782,7 @@ static void __arm_dma_free(struct device *dev, size_t size, void *cpu_addr,
                            bool is_coherent)
  {
         struct page *page = pfn_to_page(dma_to_pfn(dev, handle));
+       struct cma *cma = dev_get_cma_area(dev);
 
         if (dma_release_from_coherent(dev, get_order(size), cpu_addr))
                 return;

arch/arm/mm/dma-mapping.c +0 -1

                 __free_from_contiguous(dev, page, cpu_addr, size);
         }
  }
--

1.7.9.5

Quoted 10 lines

Date: Tue, 20 May 2014 14:16:20 +0900
Subject: [PATCH] arm: dma-mapping: add checking cma area initialized

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 <[email protected]>

Signed-off-by Joonsoo Kim <[email protected]>

Some minor comments. Also, I'd love for someone more experienced with ARM to take a look at this as well.

Quoted 9 lines

---
   arch/arm/mm/dma-mapping.c |   12 ++++++++----
   1 file changed, 8 insertions(+), 4 deletions(-)

arch/arm/mm/dma-mapping.c +0 -0

index 18e98df..61f7b93 100644

arch/arm/mm/dma-mapping.c static int __init atomic_pool_init(void) · line 382

Quoted 5 lines

arch/arm/mm/dma-mapping.c +1 -1

@@ -379,7 +379,7 @@ static int __init atomic_pool_init(void)
          unsigned long *bitmap;
          struct page *page;
          struct page **pages;
-       void *ptr;
+       void *ptr = NULL;

This is unnecessary any more.

Quoted 9 lines

arch/arm/mm/dma-mapping.c +1 -1

          int bitmap_size = BITS_TO_LONGS(nr_pages) * sizeof(long);
 
          bitmap = kzalloc(bitmap_size, GFP_KERNEL);

@@ -390,12 +390,13 @@ static int __init atomic_pool_init(void)
          if (!pages)
                  goto no_pages;
 
-       if (IS_ENABLED(CONFIG_DMA_CMA))
+       if (IS_ENABLED(CONFIG_DMA_CMA) && dma_contiguous_default_area)

(quoted diff) +1 -0

+	if (dev_get_cma_area(NULL))

dev_get_cma_area returns NULL if !IS_ENABLED(CONFIG_DMA_CMA) so there's no need to check it explicitly. And with NULL argument, deg_get_cma_area returns the default area.

Quoted 18 lines

arch/arm/mm/dma-mapping.c +2 -0

                  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;
 

@@ -669,6 +670,7 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
          u64 mask = get_coherent_dma_mask(dev);
          struct page *page = NULL;
          void *addr;
+       struct cma *cma = dev_get_cma_area(dev);
 
   #ifdef CONFIG_DMA_API_DEBUG
          u64 limit = (mask + 1) & ~mask;

arch/arm/mm/dma-mapping.c static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, · line 706

Quoted 5 lines

arch/arm/mm/dma-mapping.c +1 -1

@@ -701,7 +703,7 @@ 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 (!IS_ENABLED(CONFIG_DMA_CMA) || !cma)

Like above, just do:

(quoted diff) +1 -0

+	else if (!dev_get_cma_area(dev))

This will also allow to drop the a??cmaa?? variable above.

Quoted 12 lines

arch/arm/mm/dma-mapping.c +1 -0

                  addr = __alloc_remap_buffer(dev, size, gfp, prot, &page, caller);
          else
                  addr = __alloc_from_contiguous(dev, size, prot, &page, caller);

@@ -780,6 +782,7 @@ static void __arm_dma_free(struct device *dev, size_t size, void *cpu_addr,
                             bool is_coherent)
   {
          struct page *page = pfn_to_page(dma_to_pfn(dev, handle));
+       struct cma *cma = dev_get_cma_area(dev);
 
          if (dma_release_from_coherent(dev, get_order(size), cpu_addr))
                  return;

arch/arm/mm/dma-mapping.c static void __arm_dma_free(struct device *dev, size_t size, void *cpu_addr, · line 796

Quoted 5 lines

arch/arm/mm/dma-mapping.c +1 -1

@@ -790,7 +793,7 @@ 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 (!IS_ENABLED(CONFIG_DMA_CMA) || !cma) {

Ditto.

arch/arm/mm/dma-mapping.c static void __arm_dma_free(struct device *dev, size_t size, void *cpu_addr, · line 804

Quoted 8 lines

arch/arm/mm/dma-mapping.c +1 -0

                  __dma_free_remap(cpu_addr, size);
                  __dma_free_buffer(page, size);
          } else {

@@ -798,6 +801,7 @@ static void __arm_dma_free(struct device *dev, size_t size, void *cpu_addr,
                   * Non-atomic allocations cannot be freed with IRQs disabled
                   */
                  WARN_ON(irqs_disabled());
+

Unrelated change.

Quoted 5 lines

arch/arm/mm/dma-mapping.c +0 -1

                  __free_from_contiguous(dev, page, cpu_addr, size);
          }
   }
--

1.7.9.5

I appreciate your comments.
The previous patch was ugly. But now it's beautiful! Just 3 lines!

I'm not familiar with kernel patch process.
Can I have your name at Signed-off-by: line?
What tag do I have to write your name in?

--------------------------------- 8< ----------------------------------------------
From 135c986cfaa5a7291519308b3d47e58bf9f5af25 Mon Sep 17 00:00:00 2001
From: Gioh Kim <[email protected]>
Date: Tue, 20 May 2014 14:16:20 +0900
Subject: [PATCH] arm: dma-mapping: add checking cma area initialized

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 <[email protected]>

Signed-off-by Joonsoo Kim <[email protected]>

---
  arch/arm/mm/dma-mapping.c |    7 ++++---
  1 file changed, 4 insertions(+), 3 deletions(-)

arch/arm/mm/dma-mapping.c +4 -4

index 18e98df..9173a13 100644
@@ -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

Quoted 6 lines

I appreciate your comments.
The previous patch was ugly. But now it's beautiful! Just 3 lines!

I'm not familiar with kernel patch process.
Can I have your name at Signed-off-by: line?
What tag do I have to write your name in?

My Signed-off-by line does not apply in this case. Documentation/SubmittingPatches describes what Signed-off-by means.

I've added Acked-by below. You may want to resend this patch using a??git-send-emaila??.

Quoted 6 lines

--------------------------------- 8< ----------------------------------------------
From 135c986cfaa5a7291519308b3d47e58bf9f5af25 Mon Sep 17 00:00:00 2001
From: Gioh Kim <[email protected]>
Date: Tue, 20 May 2014 14:16:20 +0900
Subject: [PATCH] arm: dma-mapping: add checking cma area initialized

Quoted 7 lines

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 <[email protected]>

Signed-off-by Joonsoo Kim <[email protected]>

Acked-by Michal Nazarewicz <[email protected]>

But like before, if someone with more ARM knowledge could take a look at it, it would be awesome.

Quoted 35 lines

---
   arch/arm/mm/dma-mapping.c |    7 ++++---
   1 file changed, 4 insertions(+), 3 deletions(-)

arch/arm/mm/dma-mapping.c +3 -2

index 18e98df..9173a13 100644
@@ -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)) {

Quoted 8 lines

arch/arm/mm/dma-mapping.c +1 -2

                  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