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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>
This commit is contained in:
Russell King 2009-11-19 21:12:17 +00:00
parent ebd7a845fa
commit 31ebf94435
1 changed files with 16 additions and 31 deletions
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47
arch/arm/mm/dma-mapping.c
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@ -183,27 +183,13 @@ static int __init consistent_init(void)
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 @@ __dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp,
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 @@ __dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp,
return (void *)c->vm_start;
}
if (page)
__dma_free_buffer(page, size);
no_page:
*handle = ~0;
return NULL;
}
@ -315,11 +291,17 @@ static void __dma_free_remap(void *cpu_addr, size_t size)
#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 @@ __dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp,
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.