xref: /kernel/linux/linux-5.10/drivers/dma-buf/heaps/heap-helpers.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * DMABUF Heaps helper code
 *
 * Copyright (C) 2011 Google, Inc.
 * Copyright (C) 2019 Linaro Ltd.
 */

#ifndef _HEAP_HELPERS_H
#define _HEAP_HELPERS_H

#include <linux/dma-heap.h>
#include <linux/list.h>

/**
 * struct heap_helper_buffer - helper buffer metadata
 * @heap:		back pointer to the heap the buffer came from
 * @dmabuf:		backing dma-buf for this buffer
 * @size:		size of the buffer
 * @priv_virt		pointer to heap specific private value
 * @lock		mutext to protect the data in this structure
 * @vmap_cnt		count of vmap references on the buffer
 * @vaddr		vmap'ed virtual address
 * @pagecount		number of pages in the buffer
 * @pages		list of page pointers
 * @attachments		list of device attachments
 *
 * @free		heap callback to free the buffer
 */
struct heap_helper_buffer {
	struct dma_heap *heap;
	struct dma_buf *dmabuf;
	size_t size;

	void *priv_virt;
	struct mutex lock;
	int vmap_cnt;
	void *vaddr;
	pgoff_t pagecount;
	struct page **pages;
	struct list_head attachments;

	void (*free)(struct heap_helper_buffer *buffer);
};

void init_heap_helper_buffer(struct heap_helper_buffer *buffer,
			     void (*free)(struct heap_helper_buffer *));

struct dma_buf *heap_helper_export_dmabuf(struct heap_helper_buffer *buffer,
					  int fd_flags);

extern const struct dma_buf_ops heap_helper_ops;
#endif /* _HEAP_HELPERS_H */