xref: /netbsd-src/sys/external/bsd/drm2/include/linux/dma-buf.h (revision fb426d3c379e2c007704700308ff9f17d6a75dea)
1 /*	$NetBSD: dma-buf.h,v 1.12 2021/12/19 12:01:40 riastradh Exp $	*/
2 
3 /*-
4  * Copyright (c) 2018 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Taylor R. Campbell.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #ifndef _LINUX_DMA_BUF_H_
33 #define _LINUX_DMA_BUF_H_
34 
35 #include <sys/types.h>
36 #include <sys/bus.h>
37 #include <sys/mutex.h>
38 
39 #include <linux/err.h>
40 #include <linux/dma-mapping.h>
41 #include <linux/dma-resv.h>
42 #include <linux/scatterlist.h>
43 
44 struct device;
45 struct dma_buf;
46 struct dma_buf_attachment;
47 struct dma_buf_export_info;
48 struct dma_buf_ops;
49 struct file;
50 struct module;
51 struct dma_resv;
52 struct sg_table;
53 struct uvm_object;
54 
55 struct dma_buf_ops {
56 	bool	cache_sgt_mapping;
57 	bool	dynamic_mapping;
58 	int	(*attach)(struct dma_buf *, struct dma_buf_attachment *);
59 	void	(*detach)(struct dma_buf *, struct dma_buf_attachment *);
60 	struct sg_table *
61 		(*map_dma_buf)(struct dma_buf_attachment *,
62 		    enum dma_data_direction);
63 	void	(*unmap_dma_buf)(struct dma_buf_attachment *,
64 		    struct sg_table *, enum dma_data_direction);
65 	void	(*release)(struct dma_buf *);
66 	int	(*begin_cpu_access)(struct dma_buf *, enum dma_data_direction);
67 	int	(*end_cpu_access)(struct dma_buf *, enum dma_data_direction);
68 	int	(*mmap)(struct dma_buf *, off_t *, size_t, int, int *,
69 		    int *, struct uvm_object **, int *);
70 	void *	(*vmap)(struct dma_buf *);
71 	void	(*vunmap)(struct dma_buf *, void *);
72 };
73 
74 struct dma_buf {
75 	void				*priv;
76 	const struct dma_buf_ops	*ops;
77 	size_t				size;
78 	struct dma_resv			*resv;
79 
80 	kmutex_t			db_lock;
81 	volatile unsigned		db_refcnt;
82 	struct dma_resv_poll		db_resv_poll;
83 	struct dma_resv			db_resv_int[];
84 };
85 
86 struct dma_buf_attachment {
87 	void				*priv;
88 	struct dma_buf			*dmabuf;
89 	bus_dma_tag_t			dev; /* XXX expedient misnomer */
90 	bool				dynamic_mapping;
91 };
92 
93 struct dma_buf_export_info {
94 #if 0
95 	const char			*exp_name;
96 	struct module			*owner;
97 #endif
98 	const struct dma_buf_ops	*ops;
99 	size_t				size;
100 	int				flags;
101 	struct dma_resv			*resv;
102 	void				*priv;
103 };
104 
105 #define	DEFINE_DMA_BUF_EXPORT_INFO(info)				      \
106 	struct dma_buf_export_info info = { .priv = NULL }
107 
108 #define	dma_buf_attach		linux_dma_buf_attach
109 #define	dma_buf_detach		linux_dma_buf_detach
110 #define	dma_buf_dynamic_attach	linux_dma_buf_dynamic_attach
111 #define	dma_buf_export		linux_dma_buf_export
112 #define	dma_buf_fd		linux_dma_buf_fd
113 #define	dma_buf_get		linux_dma_buf_get
114 #define	dma_buf_map_attachment	linux_dma_buf_map_attachment
115 #define	dma_buf_put		linux_dma_buf_put
116 #define	dma_buf_unmap_attachment linux_dma_buf_unmap_attachment
117 #define	get_dma_buf		linux_get_dma_buf
118 
119 struct dma_buf *
120 	dma_buf_export(struct dma_buf_export_info *);
121 
122 int	dma_buf_fd(struct dma_buf *, int);
123 struct dma_buf *
124 	dma_buf_get(int);
125 void	get_dma_buf(struct dma_buf *);
126 void	dma_buf_put(struct dma_buf *);
127 
128 struct dma_buf_attachment *
129 	dma_buf_attach(struct dma_buf *, bus_dma_tag_t);
130 struct dma_buf_attachment *
131 	dma_buf_dynamic_attach(struct dma_buf *, bus_dma_tag_t, bool);
132 void	dma_buf_detach(struct dma_buf *, struct dma_buf_attachment *);
133 
134 struct sg_table *
135 	dma_buf_map_attachment(struct dma_buf_attachment *,
136 	    enum dma_data_direction);
137 void	dma_buf_unmap_attachment(struct dma_buf_attachment *,
138 	    struct sg_table *, enum dma_data_direction);
139 
140 #endif  /* _LINUX_DMA_BUF_H_ */
141