xref: /dragonfly/sys/dev/virtual/virtio/virtio/virtio.h (revision 9b9cf381)
1 /*-
2  * This header is BSD licensed so anyone can use the definitions to implement
3  * compatible drivers/servers.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of IBM nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD: src/sys/dev/virtio/virtio.h,v 1.2 2011/12/06 06:28:32 grehan Exp $
29  */
30 
31 #ifndef _VIRTIO_H_
32 #define _VIRTIO_H_
33 
34 #include <sys/types.h>
35 
36 struct vq_alloc_info;
37 
38 /* VirtIO device IDs. */
39 #define VIRTIO_ID_NETWORK	0x01
40 #define VIRTIO_ID_BLOCK		0x02
41 #define VIRTIO_ID_CONSOLE	0x03
42 #define VIRTIO_ID_ENTROPY	0x04
43 #define VIRTIO_ID_BALLOON	0x05
44 #define VIRTIO_ID_IOMEMORY	0x06
45 #define VIRTIO_ID_9P		0x09
46 
47 /* Status byte for guest to report progress. */
48 #define VIRTIO_CONFIG_STATUS_RESET	0x00
49 #define VIRTIO_CONFIG_STATUS_ACK	0x01
50 #define VIRTIO_CONFIG_STATUS_DRIVER	0x02
51 #define VIRTIO_CONFIG_STATUS_DRIVER_OK	0x04
52 #define VIRTIO_CONFIG_STATUS_FAILED	0x80
53 
54 /*
55  * Generate interrupt when the virtqueue ring is
56  * completely used, even if we've suppressed them.
57  */
58 #define VIRTIO_F_NOTIFY_ON_EMPTY (1 << 24)
59 
60 /*
61  * The guest should never negotiate this feature; it
62  * is used to detect faulty drivers.
63  */
64 #define VIRTIO_F_BAD_FEATURE (1 << 30)
65 
66 /*
67  * Some VirtIO feature bits (currently bits 28 through 31) are
68  * reserved for the transport being used (eg. virtio_ring), the
69  * rest are per-device feature bits.
70  */
71 #define VIRTIO_TRANSPORT_F_START	28
72 #define VIRTIO_TRANSPORT_F_END		32
73 
74 /*
75  * Maximum number of virtqueues per device.
76  */
77 #define VIRTIO_MAX_VIRTQUEUES 8
78 
79 /*
80  * VirtIO instance variables indices.
81  */
82 #define VIRTIO_IVAR_DEVTYPE		1
83 #define VIRTIO_IVAR_FEATURE_DESC	2
84 
85 struct virtio_feature_desc {
86 	uint64_t	 vfd_val;
87 	char		*vfd_str;
88 };
89 
90 const char *virtio_device_name(uint16_t devid);
91 int	 virtio_get_device_type(device_t dev);
92 void	 virtio_set_feature_desc(device_t dev,
93 	     struct virtio_feature_desc *feature_desc);
94 void	 virtio_describe(device_t dev, const char *msg,
95 	     uint64_t features, struct virtio_feature_desc *feature_desc);
96 
97 /*
98  * VirtIO Bus Methods.
99  */
100 uint64_t virtio_negotiate_features(device_t dev, uint64_t child_features);
101 int	 virtio_alloc_virtqueues(device_t dev, int flags, int nvqs,
102 	     struct vq_alloc_info *info);
103 int	 virtio_setup_intr(device_t dev);
104 int	 virtio_with_feature(device_t dev, uint64_t feature);
105 void	 virtio_stop(device_t dev);
106 int	 virtio_reinit(device_t dev, uint64_t features);
107 void	 virtio_reinit_complete(device_t dev);
108 
109 /*
110  * Read/write a variable amount from the device specific (ie, network)
111  * configuration region. This region is encoded in the same endian as
112  * the guest.
113  */
114 void	 virtio_read_device_config(device_t dev, bus_size_t offset,
115 	     void *dst, int length);
116 void	 virtio_write_device_config(device_t dev, bus_size_t offset,
117 	     void *src, int length);
118 
119 /* Inlined device specific read/write functions for common lengths. */
120 #define VIRTIO_RDWR_DEVICE_CONFIG(size, type)				\
121 static inline type							\
122 __CONCAT(virtio_read_dev_config_,size)(device_t dev,			\
123     bus_size_t offset)							\
124 {									\
125 	type val;							\
126 	virtio_read_device_config(dev, offset, &val, sizeof(type));	\
127 	return (val);							\
128 }									\
129 									\
130 static inline void							\
131 __CONCAT(virtio_write_dev_config_,size)(device_t dev,			\
132     bus_size_t offset, type val)					\
133 {									\
134 	virtio_write_device_config(dev, offset, &val, sizeof(type));	\
135 }
136 
137 VIRTIO_RDWR_DEVICE_CONFIG(1, uint8_t);
138 VIRTIO_RDWR_DEVICE_CONFIG(2, uint16_t);
139 VIRTIO_RDWR_DEVICE_CONFIG(4, uint32_t);
140 
141 #endif /* _VIRTIO_H_ */
142