From a69b0e855d3fd278ff6f09a23e1edf929538e304 Mon Sep 17 00:00:00 2001 From: "Andrew F. Davis" Date: Mon, 21 Oct 2019 19:03:06 +0000 Subject: dma-buf: Add dma-buf heaps framework This framework allows a unified userspace interface for dma-buf exporters, allowing userland to allocate specific types of memory for use in dma-buf sharing. Each heap is given its own device node, which a user can allocate a dma-buf fd from using the DMA_HEAP_IOC_ALLOC. This code is an evoluiton of the Android ION implementation, and a big thanks is due to its authors/maintainers over time for their effort: Rebecca Schultz Zavin, Colin Cross, Benjamin Gaignard, Laura Abbott, and many other contributors! Cc: Laura Abbott Cc: Benjamin Gaignard Cc: Sumit Semwal Cc: Liam Mark Cc: Pratik Patel Cc: Brian Starkey Cc: Vincent Donnefort Cc: Sudipto Paul Cc: Andrew F. Davis Cc: Christoph Hellwig Cc: Chenbo Feng Cc: Alistair Strachan Cc: Hridya Valsaraju Cc: Hillf Danton Cc: dri-devel@lists.freedesktop.org Reviewed-by: Benjamin Gaignard Reviewed-by: Brian Starkey Acked-by: Laura Abbott Tested-by: Ayan Kumar Halder Signed-off-by: Andrew F. Davis Signed-off-by: John Stultz Signed-off-by: Sumit Semwal Link: https://patchwork.freedesktop.org/patch/msgid/20191021190310.85221-2-john.stultz@linaro.org --- include/linux/dma-heap.h | 59 +++++++++++++++++++++++++++++++++++++++++++ include/uapi/linux/dma-heap.h | 55 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 114 insertions(+) create mode 100644 include/linux/dma-heap.h create mode 100644 include/uapi/linux/dma-heap.h (limited to 'include') diff --git a/include/linux/dma-heap.h b/include/linux/dma-heap.h new file mode 100644 index 000000000000..454e354d1ffb --- /dev/null +++ b/include/linux/dma-heap.h @@ -0,0 +1,59 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * DMABUF Heaps Allocation Infrastructure + * + * Copyright (C) 2011 Google, Inc. + * Copyright (C) 2019 Linaro Ltd. + */ + +#ifndef _DMA_HEAPS_H +#define _DMA_HEAPS_H + +#include +#include + +struct dma_heap; + +/** + * struct dma_heap_ops - ops to operate on a given heap + * @allocate: allocate dmabuf and return fd + * + * allocate returns dmabuf fd on success, -errno on error. + */ +struct dma_heap_ops { + int (*allocate)(struct dma_heap *heap, + unsigned long len, + unsigned long fd_flags, + unsigned long heap_flags); +}; + +/** + * struct dma_heap_export_info - information needed to export a new dmabuf heap + * @name: used for debugging/device-node name + * @ops: ops struct for this heap + * @priv: heap exporter private data + * + * Information needed to export a new dmabuf heap. + */ +struct dma_heap_export_info { + const char *name; + const struct dma_heap_ops *ops; + void *priv; +}; + +/** + * dma_heap_get_drvdata() - get per-heap driver data + * @heap: DMA-Heap to retrieve private data for + * + * Returns: + * The per-heap data for the heap. + */ +void *dma_heap_get_drvdata(struct dma_heap *heap); + +/** + * dma_heap_add - adds a heap to dmabuf heaps + * @exp_info: information needed to register this heap + */ +struct dma_heap *dma_heap_add(const struct dma_heap_export_info *exp_info); + +#endif /* _DMA_HEAPS_H */ diff --git a/include/uapi/linux/dma-heap.h b/include/uapi/linux/dma-heap.h new file mode 100644 index 000000000000..6ce5cc68d238 --- /dev/null +++ b/include/uapi/linux/dma-heap.h @@ -0,0 +1,55 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* + * DMABUF Heaps Userspace API + * + * Copyright (C) 2011 Google, Inc. + * Copyright (C) 2019 Linaro Ltd. + */ +#ifndef _UAPI_LINUX_DMABUF_POOL_H +#define _UAPI_LINUX_DMABUF_POOL_H + +#include +#include + +/** + * DOC: DMABUF Heaps Userspace API + */ + +/* Valid FD_FLAGS are O_CLOEXEC, O_RDONLY, O_WRONLY, O_RDWR */ +#define DMA_HEAP_VALID_FD_FLAGS (O_CLOEXEC | O_ACCMODE) + +/* Currently no heap flags */ +#define DMA_HEAP_VALID_HEAP_FLAGS (0) + +/** + * struct dma_heap_allocation_data - metadata passed from userspace for + * allocations + * @len: size of the allocation + * @fd: will be populated with a fd which provdes the + * handle to the allocated dma-buf + * @fd_flags: file descriptor flags used when allocating + * @heap_flags: flags passed to heap + * + * Provided by userspace as an argument to the ioctl + */ +struct dma_heap_allocation_data { + __u64 len; + __u32 fd; + __u32 fd_flags; + __u64 heap_flags; + __u32 reserved0; + __u32 reserved1; +}; + +#define DMA_HEAP_IOC_MAGIC 'H' + +/** + * DOC: DMA_HEAP_IOC_ALLOC - allocate memory from pool + * + * Takes an dma_heap_allocation_data struct and returns it with the fd field + * populated with the dmabuf handle of the allocation. + */ +#define DMA_HEAP_IOC_ALLOC _IOWR(DMA_HEAP_IOC_MAGIC, 0, \ + struct dma_heap_allocation_data) + +#endif /* _UAPI_LINUX_DMABUF_POOL_H */ -- cgit v1.2.3-59-g8ed1b