[PATCH v2 03/10] DMA, CMA: separate core cma management codes from DMA APIs

[Joonsoo Kim]

To prepare future generalization work on cma area management code,
we need to separate core cma management codes from DMA APIs.
We will extend these core functions to cover requirements of
ppc kvm's cma area management functionality in following patches.
This separation helps us not to touch DMA APIs while extending
core functions.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim at lge.com>

diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
index fb0cdce..8a44c82 100644
--- a/drivers/base/dma-contiguous.c
+++ b/drivers/base/dma-contiguous.c
@@ -231,9 +231,9 @@ core_initcall(cma_init_reserved_areas);
  * If @fixed is true, reserve contiguous area at exactly @base.  If false,
  * reserve in range from @base to @limit.
  */
-int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,
-				       phys_addr_t limit, struct cma **res_cma,
-				       bool fixed)
+static int __init __dma_contiguous_reserve_area(phys_addr_t size,
+				phys_addr_t base, phys_addr_t limit,
+				struct cma **res_cma, bool fixed)
 {
 	struct cma *cma = &cma_areas[cma_area_count];
 	phys_addr_t alignment;
@@ -288,16 +288,30 @@ int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,
 
 	pr_info("%s(): reserved %ld MiB at %08lx\n",
 		__func__, (unsigned long)size / SZ_1M, (unsigned long)base);
-
-	/* Architecture specific contiguous memory fixup. */
-	dma_contiguous_early_fixup(base, size);
 	return 0;
+
 err:
 	pr_err("%s(): failed to reserve %ld MiB\n",
 		__func__, (unsigned long)size / SZ_1M);
 	return ret;
 }
 
+int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,
+				       phys_addr_t limit, struct cma **res_cma,
+				       bool fixed)
+{
+	int ret;
+
+	ret = __dma_contiguous_reserve_area(size, base, limit, res_cma, fixed);
+	if (ret)
+		return ret;
+
+	/* Architecture specific contiguous memory fixup. */
+	dma_contiguous_early_fixup(base, size);
+
+	return 0;
+}
+
 static void clear_cma_bitmap(struct cma *cma, unsigned long pfn, int count)
 {
 	mutex_lock(&cma->lock);
@@ -316,20 +330,16 @@ static void clear_cma_bitmap(struct cma *cma, unsigned long pfn, int count)
  * global one. Requires architecture specific dev_get_cma_area() helper
  * function.
  */
-struct page *dma_alloc_from_contiguous(struct device *dev, int count,
+static struct page *__dma_alloc_from_contiguous(struct cma *cma, int count,
 				       unsigned int align)
 {
 	unsigned long mask, pfn, pageno, start = 0;
-	struct cma *cma = dev_get_cma_area(dev);
 	struct page *page = NULL;
 	int ret;
 
 	if (!cma || !cma->count)
 		return NULL;
 
-	if (align > CONFIG_CMA_ALIGNMENT)
-		align = CONFIG_CMA_ALIGNMENT;
-
 	pr_debug("%s(cma %p, count %d, align %d)\n", __func__, (void *)cma,
 		 count, align);
 
@@ -377,6 +387,17 @@ struct page *dma_alloc_from_contiguous(struct device *dev, int count,
 	return page;
 }
 
+struct page *dma_alloc_from_contiguous(struct device *dev, int count,
+				       unsigned int align)
+{
+	struct cma *cma = dev_get_cma_area(dev);
+
+	if (align > CONFIG_CMA_ALIGNMENT)
+		align = CONFIG_CMA_ALIGNMENT;
+
+	return __dma_alloc_from_contiguous(cma, count, align);
+}
+
 /**
  * dma_release_from_contiguous() - release allocated pages
  * @dev:   Pointer to device for which the pages were allocated.
@@ -387,10 +408,9 @@ struct page *dma_alloc_from_contiguous(struct device *dev, int count,
  * It returns false when provided pages do not belong to contiguous area and
  * true otherwise.
  */
-bool dma_release_from_contiguous(struct device *dev, struct page *pages,
+static bool __dma_release_from_contiguous(struct cma *cma, struct page *pages,
 				 int count)
 {
-	struct cma *cma = dev_get_cma_area(dev);
 	unsigned long pfn;
 
 	if (!cma || !pages)
@@ -410,3 +430,11 @@ bool dma_release_from_contiguous(struct device *dev, struct page *pages,
 
 	return true;
 }
+
+bool dma_release_from_contiguous(struct device *dev, struct page *pages,
+				 int count)
+{
+	struct cma *cma = dev_get_cma_area(dev);
+
+	return __dma_release_from_contiguous(cma, pages, count);
+}
-- 
1.7.9.5