1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * DMABUF Heaps Allocation Infrastructure
4 *
5 * Copyright (C) 2011 Google, Inc.
6 * Copyright (C) 2019 Linaro Ltd.
7 */
8
9#ifndef DMA_HEAPS_H
10#define DMA_HEAPS_H
11
12#include <linux/cdev.h>
13#include <linux/types.h>
14
15struct dma_heap;
16
17/**
18 * struct dma_heap_ops - ops to operate on a given heap
19 * @allocate:        allocate dmabuf and return struct dma_buf ptr
20 * @get_pool_size:    if heap maintains memory pools, get pool size in bytes
21 *
22 * allocate returns dmabuf on success, ERR_PTR(-errno) on error.
23 */
24struct dma_heap_ops {
25    struct dma_buf *(*allocate)(struct dma_heap *heap, unsigned long len, unsigned long fd_flags,
26                                unsigned long heap_flags);
27    long (*get_pool_size)(struct dma_heap *heap);
28};
29
30/**
31 * struct dma_heap_export_info - information needed to export a new dmabuf heap
32 * @name:    used for debugging/device-node name
33 * @ops:    ops struct for this heap
34 * @priv:    heap exporter private data
35 *
36 * Information needed to export a new dmabuf heap.
37 */
38struct dma_heap_export_info {
39    const char *name;
40    const struct dma_heap_ops *ops;
41    void *priv;
42};
43
44/**
45 * dma_heap_get_drvdata() - get per-heap driver data
46 * @heap: DMA-Heap to retrieve private data for
47 *
48 * Returns:
49 * The per-heap data for the heap.
50 */
51void *dma_heap_get_drvdata(struct dma_heap *heap);
52
53/**
54 * dma_heap_get_dev() - get device struct for the heap
55 * @heap: DMA-Heap to retrieve device struct from
56 *
57 * Returns:
58 * The device struct for the heap.
59 */
60struct device *dma_heap_get_dev(struct dma_heap *heap);
61
62/**
63 * dma_heap_get_name() - get heap name
64 * @heap: DMA-Heap to retrieve private data for
65 *
66 * Returns:
67 * The char* for the heap name.
68 */
69const char *dma_heap_get_name(struct dma_heap *heap);
70
71/**
72 * dma_heap_add - adds a heap to dmabuf heaps
73 * @exp_info:        information needed to register this heap
74 */
75struct dma_heap *dma_heap_add(const struct dma_heap_export_info *exp_info);
76
77/**
78 * dma_heap_put - drops a reference to a dmabuf heaps, potentially freeing it
79 * @heap:        heap pointer
80 */
81void dma_heap_put(struct dma_heap *heap);
82
83/**
84 * dma_heap_find - Returns the registered dma_heap with the specified name
85 * @name: Name of the heap to find
86 *
87 * NOTE: dma_heaps returned from this function MUST be released
88 * using dma_heap_put() when the user is done.
89 */
90struct dma_heap *dma_heap_find(const char *name);
91
92/**
93 * dma_heap_buffer_alloc - Allocate dma-buf from a dma_heap
94 * @heap:    dma_heap to allocate from
95 * @len:    size to allocate
96 * @fd_flags:    flags to set on returned dma-buf fd
97 * @heap_flags:    flags to pass to the dma heap
98 *
99 * This is for internal dma-buf allocations only.
100 */
101struct dma_buf *dma_heap_buffer_alloc(struct dma_heap *heap, size_t len, unsigned int fd_flags,
102                                      unsigned int heap_flags);
103
104/** dma_heap_buffer_free - Free dma_buf allocated by dma_heap_buffer_alloc
105 * @dma_buf:    dma_buf to free
106 *
107 * This is really only a simple wrapper to dma_buf_put()
108 */
109void dma_heap_buffer_free(struct dma_buf *);
110
111/**
112 * dma_heap_bufferfd_alloc - Allocate dma-buf fd from a dma_heap
113 * @heap:    dma_heap to allocate from
114 * @len:    size to allocate
115 * @fd_flags:    flags to set on returned dma-buf fd
116 * @heap_flags:    flags to pass to the dma heap
117 */
118int dma_heap_bufferfd_alloc(struct dma_heap *heap, size_t len, unsigned int fd_flags, unsigned int heap_flags);
119#endif /* _DMA_HEAPS_H */
120