xref: /freebsd/sys/dev/virtio/virtio.c (revision f5f47d5068fb97df18eb114a66ae8ef51a0b3c8c)
1 /*-
2  * Copyright (c) 2011, Bryan Venteicher <bryanv@daemoninthecloset.org>
3  * All rights reserved.
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 unmodified, this list of conditions, and the following
10  *    disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/malloc.h>
34 #include <sys/module.h>
35 #include <sys/sbuf.h>
36 
37 #include <machine/bus.h>
38 #include <machine/resource.h>
39 #include <machine/_inttypes.h>
40 #include <sys/bus.h>
41 #include <sys/rman.h>
42 
43 #include <dev/virtio/virtio.h>
44 #include <dev/virtio/virtqueue.h>
45 
46 #include "virtio_bus_if.h"
47 
48 static int virtio_modevent(module_t, int, void *);
49 static const char *virtio_feature_name(uint64_t, struct virtio_feature_desc *);
50 
51 static struct virtio_ident {
52 	uint16_t devid;
53 	char	*name;
54 } virtio_ident_table[] = {
55 	{ VIRTIO_ID_NETWORK,	"Network"	},
56 	{ VIRTIO_ID_BLOCK,	"Block"		},
57 	{ VIRTIO_ID_CONSOLE,	"Console"	},
58 	{ VIRTIO_ID_ENTROPY,	"Entropy"	},
59 	{ VIRTIO_ID_BALLOON,	"Balloon"	},
60 	{ VIRTIO_ID_IOMEMORY,	"IOMemory"	},
61 	{ VIRTIO_ID_9P,		"9P Transport"	},
62 
63 	{ 0, NULL }
64 };
65 
66 /* Device independent features. */
67 static struct virtio_feature_desc virtio_common_feature_desc[] = {
68 	{ VIRTIO_F_NOTIFY_ON_EMPTY,	"NotifyOnEmpty"	},
69 	{ VIRTIO_RING_F_INDIRECT_DESC,	"RingIndirect"	},
70 	{ VIRTIO_RING_F_EVENT_IDX,	"EventIdx"	},
71 	{ VIRTIO_F_BAD_FEATURE,		"BadFeature"	},
72 
73 	{ 0, NULL }
74 };
75 
76 const char *
77 virtio_device_name(uint16_t devid)
78 {
79 	struct virtio_ident *ident;
80 
81 	for (ident = virtio_ident_table; ident->name != NULL; ident++) {
82 		if (ident->devid == devid)
83 			return (ident->name);
84 	}
85 
86 	return (NULL);
87 }
88 
89 void
90 virtio_describe(device_t dev, const char *msg,
91     uint64_t features, struct virtio_feature_desc *feature_desc)
92 {
93 	struct sbuf sb;
94 	uint64_t val;
95 	char *buf;
96 	const char *name;
97 	int n;
98 
99 	if ((buf = malloc(512, M_TEMP, M_NOWAIT)) == NULL) {
100 		device_printf(dev, "%s features: 0x%"PRIx64"\n", msg,
101 		    features);
102 		return;
103 	}
104 
105 	sbuf_new(&sb, buf, 512, SBUF_FIXEDLEN);
106 	sbuf_printf(&sb, "%s features: 0x%"PRIx64, msg, features);
107 
108 	for (n = 0, val = 1ULL << 63; val != 0; val >>= 1) {
109 		/*
110 		 * BAD_FEATURE is used to detect broken Linux clients
111 		 * and therefore is not applicable to FreeBSD.
112 		 */
113 		if (((features & val) == 0) || val == VIRTIO_F_BAD_FEATURE)
114 			continue;
115 
116 		if (n++ == 0)
117 			sbuf_cat(&sb, " <");
118 		else
119 			sbuf_cat(&sb, ",");
120 
121 		name = NULL;
122 		if (feature_desc != NULL)
123 			name = virtio_feature_name(val, feature_desc);
124 		if (name == NULL)
125 			name = virtio_feature_name(val,
126 			    virtio_common_feature_desc);
127 
128 		if (name == NULL)
129 			sbuf_printf(&sb, "0x%"PRIx64, val);
130 		else
131 			sbuf_cat(&sb, name);
132 	}
133 
134 	if (n > 0)
135 		sbuf_cat(&sb, ">");
136 
137 #if __FreeBSD_version < 900020
138 	sbuf_finish(&sb);
139 	if (sbuf_overflowed(&sb) == 0)
140 #else
141 	if (sbuf_finish(&sb) == 0)
142 #endif
143 		device_printf(dev, "%s\n", sbuf_data(&sb));
144 
145 	sbuf_delete(&sb);
146 	free(buf, M_TEMP);
147 }
148 
149 static const char *
150 virtio_feature_name(uint64_t val, struct virtio_feature_desc *feature_desc)
151 {
152 	int i;
153 
154 	for (i = 0; feature_desc[i].vfd_val != 0; i++)
155 		if (val == feature_desc[i].vfd_val)
156 			return (feature_desc[i].vfd_str);
157 
158 	return (NULL);
159 }
160 
161 /*
162  * VirtIO bus method wrappers.
163  */
164 
165 void
166 virtio_read_ivar(device_t dev, int ivar, uintptr_t *val)
167 {
168 
169 	*val = -1;
170 	BUS_READ_IVAR(device_get_parent(dev), dev, ivar, val);
171 }
172 
173 void
174 virtio_write_ivar(device_t dev, int ivar, uintptr_t val)
175 {
176 
177 	BUS_WRITE_IVAR(device_get_parent(dev), dev, ivar, val);
178 }
179 
180 uint64_t
181 virtio_negotiate_features(device_t dev, uint64_t child_features)
182 {
183 
184 	return (VIRTIO_BUS_NEGOTIATE_FEATURES(device_get_parent(dev),
185 	    child_features));
186 }
187 
188 int
189 virtio_alloc_virtqueues(device_t dev, int flags, int nvqs,
190     struct vq_alloc_info *info)
191 {
192 
193 	return (VIRTIO_BUS_ALLOC_VIRTQUEUES(device_get_parent(dev), flags,
194 	    nvqs, info));
195 }
196 
197 int
198 virtio_setup_intr(device_t dev, enum intr_type type)
199 {
200 
201 	return (VIRTIO_BUS_SETUP_INTR(device_get_parent(dev), type));
202 }
203 
204 int
205 virtio_with_feature(device_t dev, uint64_t feature)
206 {
207 
208 	return (VIRTIO_BUS_WITH_FEATURE(device_get_parent(dev), feature));
209 }
210 
211 void
212 virtio_stop(device_t dev)
213 {
214 
215 	VIRTIO_BUS_STOP(device_get_parent(dev));
216 }
217 
218 int
219 virtio_reinit(device_t dev, uint64_t features)
220 {
221 
222 	return (VIRTIO_BUS_REINIT(device_get_parent(dev), features));
223 }
224 
225 void
226 virtio_reinit_complete(device_t dev)
227 {
228 
229 	VIRTIO_BUS_REINIT_COMPLETE(device_get_parent(dev));
230 }
231 
232 void
233 virtio_read_device_config(device_t dev, bus_size_t offset, void *dst, int len)
234 {
235 
236 	VIRTIO_BUS_READ_DEVICE_CONFIG(device_get_parent(dev),
237 	    offset, dst, len);
238 }
239 
240 void
241 virtio_write_device_config(device_t dev, bus_size_t offset, void *dst, int len)
242 {
243 
244 	VIRTIO_BUS_WRITE_DEVICE_CONFIG(device_get_parent(dev),
245 	    offset, dst, len);
246 }
247 
248 static int
249 virtio_modevent(module_t mod, int type, void *unused)
250 {
251 	int error;
252 
253 	error = 0;
254 
255 	switch (type) {
256 	case MOD_LOAD:
257 	case MOD_QUIESCE:
258 	case MOD_UNLOAD:
259 	case MOD_SHUTDOWN:
260 		break;
261 	default:
262 		error = EOPNOTSUPP;
263 		break;
264 	}
265 
266 	return (error);
267 }
268 
269 static moduledata_t virtio_mod = {
270 	"virtio",
271 	virtio_modevent,
272 	0
273 };
274 
275 DECLARE_MODULE(virtio, virtio_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
276 MODULE_VERSION(virtio, 1);
277