diff options
Diffstat (limited to 'kernel/dma-coherent.c')
| -rw-r--r-- | kernel/dma-coherent.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/kernel/dma-coherent.c b/kernel/dma-coherent.c index 56dff5cb0f2..7517115a8cc 100644 --- a/kernel/dma-coherent.c +++ b/kernel/dma-coherent.c @@ -92,6 +92,21 @@ void *dma_mark_declared_memory_occupied(struct device *dev, } EXPORT_SYMBOL(dma_mark_declared_memory_occupied); +/** + * Try to allocate memory from the per-device coherent area. + * + * @dev: device from which we allocate memory + * @size: size of requested memory area + * @dma_handle: This will be filled with the correct dma handle + * @ret: This pointer will be filled with the virtual address + * to allocated area. + * + * This function should be only called from per-arch %dma_alloc_coherent() + * to support allocation from per-device coherent memory pools. + * + * Returns 0 if dma_alloc_coherent should continue with allocating from + * generic memory areas, or !0 if dma_alloc_coherent should return %ret. + */ int dma_alloc_from_coherent(struct device *dev, ssize_t size, dma_addr_t *dma_handle, void **ret) { @@ -111,6 +126,19 @@ int dma_alloc_from_coherent(struct device *dev, ssize_t size, return (mem != NULL); } +/** + * Try to free the memory allocated from per-device coherent memory pool. + * @dev: device from which the memory was allocated + * @order: the order of pages allocated + * @vaddr: virtual address of allocated pages + * + * This checks whether the memory was allocated from the per-device + * coherent memory pool and if so, releases that memory. + * + * Returns 1 if we correctly released the memory, or 0 if + * %dma_release_coherent() should proceed with releasing memory from + * generic pools. + */ int dma_release_from_coherent(struct device *dev, int order, void *vaddr) { struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL; |