commit 31ebf94435f74294523683867fe0b89000e61521
author Russell King <rmk+kernel@arm.linux.org.uk> Thu Nov 19 21:12:17 2009 +0000
committer Russell King <rmk+kernel@arm.linux.org.uk> Tue Nov 24 17:41:35 2009 +0000
tree 57f587da490f9c8bbf987d4165a5ede7f7ad5d63
parent ebd7a845fa4332da3ebcbe8cf1b09bb43413420e

ARM: dma-mapping: Factor out noMMU dma buffer allocation code

This entirely separates the DMA coherent buffer remapping code from
the allocation code, and gets rid of the duplicate copy in the !MMU
section.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Ungerer <gerg@uclinux.org>

arch/arm/mm/dma-mapping.c

diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 3a8e527..707d812 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -183,27 +183,13 @@
 core_initcall(consistent_init);
 
 static void *
-__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp,
-	    pgprot_t prot)
+__dma_alloc_remap(struct page *page, size_t size, gfp_t gfp, pgprot_t prot)
 {
-	struct page *page;
 	struct arm_vmregion *c;
 
-	size = PAGE_ALIGN(size);
-
-	page = __dma_alloc_buffer(dev, size, gfp);
-	if (!page)
-		goto no_page;
-
-	if (arch_is_coherent()) {
-		*handle = page_to_dma(dev, page);
-		return page_address(page);
-	}
-
 	if (!consistent_pte[0]) {
 		printk(KERN_ERR "%s: not initialised\n", __func__);
 		dump_stack();
-		__dma_free_buffer(page, size);
 		return NULL;
 	}
 
@@ -220,11 +206,6 @@
 		pte = consistent_pte[idx] + off;
 		c->vm_pages = page;
 
-		/*
-		 * Set the "dma handle"
-		 */
-		*handle = page_to_dma(dev, page);
-
 		do {
 			BUG_ON(!pte_none(*pte));
 
@@ -244,11 +225,6 @@
 
 		return (void *)c->vm_start;
 	}
-
-	if (page)
-		__dma_free_buffer(page, size);
- no_page:
-	*handle = ~0;
 	return NULL;
 }
 
@@ -315,11 +291,17 @@
 
 #else	/* !CONFIG_MMU */
 
+#define __dma_alloc_remap(page, size, gfp, prot)	page_address(page)
+#define __dma_free_remap(addr, size)			do { } while (0)
+
+#endif	/* CONFIG_MMU */
+
 static void *
 __dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp,
 	    pgprot_t prot)
 {
 	struct page *page;
+	void *addr;
 
 	*handle = ~0;
 	size = PAGE_ALIGN(size);
@@ -328,14 +310,17 @@
 	if (!page)
 		return NULL;
 
-	*handle = page_to_dma(dev, page);
-	return page_address(page);
+	if (!arch_is_coherent())
+		addr = __dma_alloc_remap(page, size, gfp, prot);
+	else
+		addr = page_address(page);
+
+	if (addr)
+		*handle = page_to_dma(dev, page);
+
+	return addr;
 }
 
-#define __dma_free_remap(addr, size)	do { } while (0)
-
-#endif	/* CONFIG_MMU */
-
 /*
  * Allocate DMA-coherent memory space and return both the kernel remapped
  * virtual and bus address for that space.