This patchset introduces a new dma heap, chunk heap that makes it easy to perform the bulk allocation of high order pages. It has been created to help optimize the 4K/8K HDR video playback with secure DRM HW to protect contents on memory. The HW needs physically contiguous memory chunks up to several hundred MB memory.
The chunk heap is registered by device tree with alignment and memory node of Contiguous Memory Allocator(CMA). Alignment defines chunk page size. For example, alignment 0x1_0000 means chunk page size is 64KB. The phandle to memory node indicates contiguous memory allocator(CMA). If device node doesn't have cma, the registration of chunk heap fails.
This patchset is against on next-20201110.
The patchset includes the following: - cma_alloc_bulk API - export dma-heap API to register kernel module dma heap. - add chunk heap implementation. - devicetree
Hyesoo Yu (3): dma-buf: add export symbol for dma-heap dma-buf: heaps: add chunk heap to dmabuf heaps dma-heap: Devicetree binding for chunk heap
Minchan Kim (1): mm: introduce cma_alloc_bulk API
.../bindings/dma-buf/chunk_heap.yaml | 52 ++ drivers/dma-buf/dma-heap.c | 2 + drivers/dma-buf/heaps/Kconfig | 9 + drivers/dma-buf/heaps/Makefile | 1 + drivers/dma-buf/heaps/chunk_heap.c | 458 ++++++++++++++++++ include/linux/cma.h | 5 + include/linux/page-isolation.h | 1 + mm/cma.c | 129 ++++- mm/page_alloc.c | 19 +- mm/page_isolation.c | 3 +- 10 files changed, 666 insertions(+), 13 deletions(-) create mode 100644 Documentation/devicetree/bindings/dma-buf/chunk_heap.yaml create mode 100644 drivers/dma-buf/heaps/chunk_heap.c