xref: /netbsd-src/sys/external/bsd/drm2/include/linux/dma-buf.h (revision 627f7eb200a4419d89b531d55fccd2ee3ffdcde0)
1 /*	$NetBSD: dma-buf.h,v 1.4 2018/08/27 15:25:13 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/reservation.h>
40 
41 struct device;
42 struct dma_buf;
43 struct dma_buf_attachment;
44 struct dma_buf_export_info;
45 struct dma_buf_ops;
46 struct file;
47 struct module;
48 struct reservation_object;
49 struct sg_table;
50 struct uvm_object;
51 
52 enum dma_data_direction {
53 	DMA_NONE		= 0,
54 	DMA_TO_DEVICE		= 1,
55 	DMA_FROM_DEVICE		= 2,
56 	DMA_BIDIRECTIONAL	= 3,
57 };
58 
59 struct dma_buf_ops {
60 	int	(*attach)(struct dma_buf *, struct device *,
61 		    struct dma_buf_attachment *);
62 	void	(*detach)(struct dma_buf *, struct dma_buf_attachment *);
63 	struct sg_table *
64 		(*map_dma_buf)(struct dma_buf_attachment *,
65 		    enum dma_data_direction);
66 	void	(*unmap_dma_buf)(struct dma_buf_attachment *,
67 		    struct sg_table *, enum dma_data_direction);
68 	void	(*release)(struct dma_buf *);
69 	int	(*begin_cpu_access)(struct dma_buf *, size_t, size_t,
70 		    enum dma_data_direction);
71 	int	(*end_cpu_access)(struct dma_buf *, size_t, size_t,
72 		    enum dma_data_direction);
73 	void *	(*kmap_atomic)(struct dma_buf *, unsigned long);
74 	void	(*kunmap_atomic)(struct dma_buf *, unsigned long, void *);
75 	void *	(*kmap)(struct dma_buf *, unsigned long);
76 	void	(*kunmap)(struct dma_buf *, unsigned long, void *);
77 	int	(*mmap)(struct dma_buf *, off_t *, size_t, int, int *,
78 		    int *, struct uvm_object **, int *);
79 	void *	(*vmap)(struct dma_buf *);
80 	void	(*vunmap)(struct dma_buf *, void *);
81 };
82 
83 struct dma_buf {
84 	void				*priv;
85 	const struct dma_buf_ops	*ops;
86 	size_t				size;
87 	struct reservation_object	*resv;
88 
89 	kmutex_t			db_lock;
90 	volatile unsigned		db_refcnt;
91 	struct reservation_poll		db_resv_poll;
92 	struct reservation_object	db_resv_int[];
93 };
94 
95 struct dma_buf_attachment {
96 	void				*priv;
97 	struct dma_buf			*dmabuf;
98 };
99 
100 struct dma_buf_export_info {
101 #if 0
102 	const char			*exp_name;
103 	struct module			*owner;
104 #endif
105 	const struct dma_buf_ops	*ops;
106 	size_t				size;
107 	int				flags;
108 	struct reservation_object	*resv;
109 	void				*priv;
110 };
111 
112 #define	DEFINE_DMA_BUF_EXPORT_INFO(info)				      \
113 	struct dma_buf_export_info info = { .priv = NULL }
114 
115 #define	dma_buf_attach		linux_dma_buf_attach
116 #define	dma_buf_detach		linux_dma_buf_detach
117 #define	dma_buf_export		linux_dma_buf_export
118 #define	dma_buf_fd		linux_dma_buf_fd
119 #define	dma_buf_get		linux_dma_buf_get
120 #define	dma_buf_map_attachment	linux_dma_buf_map_attachment
121 #define	dma_buf_put		linux_dma_buf_put
122 #define	dma_buf_unmap_attachment linux_dma_buf_unmap_attachment
123 #define	get_dma_buf		linux_get_dma_buf
124 
125 struct dma_buf *
126 	dma_buf_export(struct dma_buf_export_info *);
127 
128 int	dma_buf_fd(struct dma_buf *, int);
129 struct dma_buf *
130 	dma_buf_get(int);
131 void	get_dma_buf(struct dma_buf *);
132 void	dma_buf_put(struct dma_buf *);
133 
134 struct dma_buf_attachment *
135 	dma_buf_attach(struct dma_buf *, struct device *);
136 void	dma_buf_detach(struct dma_buf *, struct dma_buf_attachment *);
137 
138 struct sg_table *
139 	dma_buf_map_attachment(struct dma_buf_attachment *,
140 	    enum dma_data_direction);
141 void	dma_buf_unmap_attachment(struct dma_buf_attachment *,
142 	    struct sg_table *, enum dma_data_direction);
143 
144 #endif  /* _LINUX_DMA_BUF_H_ */
145