root/include/uapi/linux/dma-heap.h
/* 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 <linux/ioctl.h>
#include <linux/types.h>

/**
 * 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 (0ULL)

/**
 * struct dma_heap_allocation_data - metadata passed from userspace for
 *                                      allocations
 * @len:                size of the allocation
 * @fd:                 will be populated with a fd which provides 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;
};

#define DMA_HEAP_IOC_MAGIC              'H'

/**
 * DOC: DMA_HEAP_IOCTL_ALLOC - allocate memory from pool
 *
 * Takes a dma_heap_allocation_data struct and returns it with the fd field
 * populated with the dmabuf handle of the allocation.
 */
#define DMA_HEAP_IOCTL_ALLOC    _IOWR(DMA_HEAP_IOC_MAGIC, 0x0,\
                                      struct dma_heap_allocation_data)

#endif /* _UAPI_LINUX_DMABUF_POOL_H */