powerpc: Implement dma_mmap_coherent()

This is used by Alsa to mmap buffers allocated with dma_alloc_coherent()
into userspace. We need a special variant to handle machines with
non-coherent DMAs as those buffers have "special" virt addresses and
require non-cachable mappings

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Benjamin Herrenschmidt
2011-03-24 20:50:06 +00:00
parent 15d260b36f
commit 6090912c4a
3 changed files with 44 additions and 0 deletions

View File

@@ -42,6 +42,7 @@ extern void __dma_free_coherent(size_t size, void *vaddr);
extern void __dma_sync(void *vaddr, size_t size, int direction);
extern void __dma_sync_page(struct page *page, unsigned long offset,
size_t size, int direction);
extern unsigned long __dma_get_coherent_pfn(unsigned long cpu_addr);
#else /* ! CONFIG_NOT_COHERENT_CACHE */
/*
@@ -198,6 +199,11 @@ static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
#define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
#define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
extern int dma_mmap_coherent(struct device *, struct vm_area_struct *,
void *, dma_addr_t, size_t);
#define ARCH_HAS_DMA_MMAP_COHERENT
static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
enum dma_data_direction direction)
{