Commit ebd7a845 authored by Russell King's avatar Russell King
Browse files

ARM: dma-mapping: clean up coherent arch dma allocation 



IXP23xx added support for dma_alloc_coherent() for DMA arches with an
exception in dma_alloc_coherent().  This is a subset of what goes on
in __dma_alloc(), and there is no reason why dma_alloc_writecombine()
should not be given the same treatment (except, maybe, that IXP23xx
doesn't use it.)

We can better deal with this by moving the arch_is_coherent() test
inside __dma_alloc() and killing the code duplication.

Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
Acked-by: default avatarGreg Ungerer <gerg@uclinux.org>
parent 88c58f3b

arch/arm/mm/dma-mapping.c

+12 −19
Original line number Diff line number Diff line
@@ -189,18 +189,24 @@ __dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp, 
	struct page *page;

	struct arm_vmregion *c;



	if (!consistent_pte[0]) {

		printk(KERN_ERR "%s: not initialised\n", __func__);

		dump_stack();

		return NULL;

	}



	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;

	}



	/*

	 * Allocate a virtual address in the consistent mapping region.

	 */
@@ -342,19 +348,6 @@ dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gf 
	if (dma_alloc_from_coherent(dev, size, handle, &memory))

		return memory;



	if (arch_is_coherent()) {

		struct page *page;



		page = __dma_alloc_buffer(dev, PAGE_ALIGN(size), gfp);

		if (!page) {

			*handle = ~0;

			return NULL;

		}



		*handle = page_to_dma(dev, page);

		return page_address(page);

	}



	return __dma_alloc(dev, size, handle, gfp,

			   pgprot_noncached(pgprot_kernel));

}

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