xref: /freebsd/sys/dev/virtio/virtio.c (revision fe267a559009cbf34f9341666fe4d88a92c02d5e)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2011, Bryan Venteicher <bryanv@FreeBSD.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice unmodified, this list of conditions, and the following
12  *    disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kernel.h>
35 #include <sys/malloc.h>
36 #include <sys/module.h>
37 #include <sys/sbuf.h>
38 
39 #include <machine/bus.h>
40 #include <machine/resource.h>
41 #include <sys/bus.h>
42 #include <sys/rman.h>
43 
44 #include <dev/virtio/virtio.h>
45 #include <dev/virtio/virtio_config.h>
46 #include <dev/virtio/virtqueue.h>
47 
48 #include "virtio_bus_if.h"
49 
50 static int virtio_modevent(module_t, int, void *);
51 static const char *virtio_feature_name(uint64_t, struct virtio_feature_desc *);
52 
53 static struct virtio_ident {
54 	uint16_t	devid;
55 	const char	*name;
56 } virtio_ident_table[] = {
57 	{ VIRTIO_ID_NETWORK,	"Network"	},
58 	{ VIRTIO_ID_BLOCK,	"Block"		},
59 	{ VIRTIO_ID_CONSOLE,	"Console"	},
60 	{ VIRTIO_ID_ENTROPY,	"Entropy"	},
61 	{ VIRTIO_ID_BALLOON,	"Balloon"	},
62 	{ VIRTIO_ID_IOMEMORY,	"IOMemory"	},
63 	{ VIRTIO_ID_SCSI,	"SCSI"		},
64 	{ VIRTIO_ID_9P,		"9P Transport"	},
65 
66 	{ 0, NULL }
67 };
68 
69 /* Device independent features. */
70 static struct virtio_feature_desc virtio_common_feature_desc[] = {
71 	{ VIRTIO_F_NOTIFY_ON_EMPTY,	"NotifyOnEmpty"	},
72 	{ VIRTIO_RING_F_INDIRECT_DESC,	"RingIndirect"	},
73 	{ VIRTIO_RING_F_EVENT_IDX,	"EventIdx"	},
74 	{ VIRTIO_F_BAD_FEATURE,		"BadFeature"	},
75 
76 	{ 0, NULL }
77 };
78 
79 const char *
80 virtio_device_name(uint16_t devid)
81 {
82 	struct virtio_ident *ident;
83 
84 	for (ident = virtio_ident_table; ident->name != NULL; ident++) {
85 		if (ident->devid == devid)
86 			return (ident->name);
87 	}
88 
89 	return (NULL);
90 }
91 
92 static const char *
93 virtio_feature_name(uint64_t val, struct virtio_feature_desc *desc)
94 {
95 	int i, j;
96 	struct virtio_feature_desc *descs[2] = { desc,
97 	    virtio_common_feature_desc };
98 
99 	for (i = 0; i < 2; i++) {
100 		if (descs[i] == NULL)
101 			continue;
102 
103 		for (j = 0; descs[i][j].vfd_val != 0; j++) {
104 			if (val == descs[i][j].vfd_val)
105 				return (descs[i][j].vfd_str);
106 		}
107 	}
108 
109 	return (NULL);
110 }
111 
112 void
113 virtio_describe(device_t dev, const char *msg,
114     uint64_t features, struct virtio_feature_desc *desc)
115 {
116 	struct sbuf sb;
117 	uint64_t val;
118 	char *buf;
119 	const char *name;
120 	int n;
121 
122 	if ((buf = malloc(512, M_TEMP, M_NOWAIT)) == NULL) {
123 		device_printf(dev, "%s features: %#jx\n", msg, (uintmax_t) features);
124 		return;
125 	}
126 
127 	sbuf_new(&sb, buf, 512, SBUF_FIXEDLEN);
128 	sbuf_printf(&sb, "%s features: %#jx", msg, (uintmax_t) features);
129 
130 	for (n = 0, val = 1ULL << 63; val != 0; val >>= 1) {
131 		/*
132 		 * BAD_FEATURE is used to detect broken Linux clients
133 		 * and therefore is not applicable to FreeBSD.
134 		 */
135 		if (((features & val) == 0) || val == VIRTIO_F_BAD_FEATURE)
136 			continue;
137 
138 		if (n++ == 0)
139 			sbuf_cat(&sb, " <");
140 		else
141 			sbuf_cat(&sb, ",");
142 
143 		name = virtio_feature_name(val, desc);
144 		if (name == NULL)
145 			sbuf_printf(&sb, "%#jx", (uintmax_t) val);
146 		else
147 			sbuf_cat(&sb, name);
148 	}
149 
150 	if (n > 0)
151 		sbuf_cat(&sb, ">");
152 
153 #if __FreeBSD_version < 900020
154 	sbuf_finish(&sb);
155 	if (sbuf_overflowed(&sb) == 0)
156 #else
157 	if (sbuf_finish(&sb) == 0)
158 #endif
159 		device_printf(dev, "%s\n", sbuf_data(&sb));
160 
161 	sbuf_delete(&sb);
162 	free(buf, M_TEMP);
163 }
164 
165 /*
166  * VirtIO bus method wrappers.
167  */
168 
169 void
170 virtio_read_ivar(device_t dev, int ivar, uintptr_t *val)
171 {
172 
173 	*val = -1;
174 	BUS_READ_IVAR(device_get_parent(dev), dev, ivar, val);
175 }
176 
177 void
178 virtio_write_ivar(device_t dev, int ivar, uintptr_t val)
179 {
180 
181 	BUS_WRITE_IVAR(device_get_parent(dev), dev, ivar, val);
182 }
183 
184 uint64_t
185 virtio_negotiate_features(device_t dev, uint64_t child_features)
186 {
187 
188 	return (VIRTIO_BUS_NEGOTIATE_FEATURES(device_get_parent(dev),
189 	    child_features));
190 }
191 
192 int
193 virtio_alloc_virtqueues(device_t dev, int flags, int nvqs,
194     struct vq_alloc_info *info)
195 {
196 
197 	return (VIRTIO_BUS_ALLOC_VIRTQUEUES(device_get_parent(dev), flags,
198 	    nvqs, info));
199 }
200 
201 int
202 virtio_setup_intr(device_t dev, enum intr_type type)
203 {
204 
205 	return (VIRTIO_BUS_SETUP_INTR(device_get_parent(dev), type));
206 }
207 
208 int
209 virtio_with_feature(device_t dev, uint64_t feature)
210 {
211 
212 	return (VIRTIO_BUS_WITH_FEATURE(device_get_parent(dev), feature));
213 }
214 
215 void
216 virtio_stop(device_t dev)
217 {
218 
219 	VIRTIO_BUS_STOP(device_get_parent(dev));
220 }
221 
222 int
223 virtio_reinit(device_t dev, uint64_t features)
224 {
225 
226 	return (VIRTIO_BUS_REINIT(device_get_parent(dev), features));
227 }
228 
229 void
230 virtio_reinit_complete(device_t dev)
231 {
232 
233 	VIRTIO_BUS_REINIT_COMPLETE(device_get_parent(dev));
234 }
235 
236 void
237 virtio_read_device_config(device_t dev, bus_size_t offset, void *dst, int len)
238 {
239 
240 	VIRTIO_BUS_READ_DEVICE_CONFIG(device_get_parent(dev),
241 	    offset, dst, len);
242 }
243 
244 void
245 virtio_write_device_config(device_t dev, bus_size_t offset, void *dst, int len)
246 {
247 
248 	VIRTIO_BUS_WRITE_DEVICE_CONFIG(device_get_parent(dev),
249 	    offset, dst, len);
250 }
251 
252 static int
253 virtio_modevent(module_t mod, int type, void *unused)
254 {
255 	int error;
256 
257 	switch (type) {
258 	case MOD_LOAD:
259 	case MOD_QUIESCE:
260 	case MOD_UNLOAD:
261 	case MOD_SHUTDOWN:
262 		error = 0;
263 		break;
264 	default:
265 		error = EOPNOTSUPP;
266 		break;
267 	}
268 
269 	return (error);
270 }
271 
272 static moduledata_t virtio_mod = {
273 	"virtio",
274 	virtio_modevent,
275 	0
276 };
277 
278 DECLARE_MODULE(virtio, virtio_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
279 MODULE_VERSION(virtio, 1);
280