xref: /freebsd/sys/dev/virtio/virtio.c (revision b2d48be1bc7df45ddd13b143a160d0acb5a383c5)
1 /*-
2  * Copyright (c) 2011, Bryan Venteicher <bryanv@FreeBSD.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 <sys/bus.h>
40 #include <sys/rman.h>
41 
42 #include <dev/virtio/virtio.h>
43 #include <dev/virtio/virtio_config.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 	const 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_SCSI,	"SCSI"		},
62 	{ VIRTIO_ID_9P,		"9P Transport"	},
63 
64 	{ 0, NULL }
65 };
66 
67 /* Device independent features. */
68 static struct virtio_feature_desc virtio_common_feature_desc[] = {
69 	{ VIRTIO_F_NOTIFY_ON_EMPTY,	"NotifyOnEmpty"	},
70 	{ VIRTIO_RING_F_INDIRECT_DESC,	"RingIndirect"	},
71 	{ VIRTIO_RING_F_EVENT_IDX,	"EventIdx"	},
72 	{ VIRTIO_F_BAD_FEATURE,		"BadFeature"	},
73 
74 	{ 0, NULL }
75 };
76 
77 const char *
78 virtio_device_name(uint16_t devid)
79 {
80 	struct virtio_ident *ident;
81 
82 	for (ident = virtio_ident_table; ident->name != NULL; ident++) {
83 		if (ident->devid == devid)
84 			return (ident->name);
85 	}
86 
87 	return (NULL);
88 }
89 
90 static const char *
91 virtio_feature_name(uint64_t val, struct virtio_feature_desc *desc)
92 {
93 	int i, j;
94 	struct virtio_feature_desc *descs[2] = { desc,
95 	    virtio_common_feature_desc };
96 
97 	for (i = 0; i < 2; i++) {
98 		if (descs[i] == NULL)
99 			continue;
100 
101 		for (j = 0; descs[i][j].vfd_val != 0; j++) {
102 			if (val == descs[i][j].vfd_val)
103 				return (descs[i][j].vfd_str);
104 		}
105 	}
106 
107 	return (NULL);
108 }
109 
110 void
111 virtio_describe(device_t dev, const char *msg,
112     uint64_t features, struct virtio_feature_desc *desc)
113 {
114 	struct sbuf sb;
115 	uint64_t val;
116 	char *buf;
117 	const char *name;
118 	int n;
119 
120 	if ((buf = malloc(512, M_TEMP, M_NOWAIT)) == NULL) {
121 		device_printf(dev, "%s features: %#jx\n", msg, (uintmax_t) features);
122 		return;
123 	}
124 
125 	sbuf_new(&sb, buf, 512, SBUF_FIXEDLEN);
126 	sbuf_printf(&sb, "%s features: %#jx", msg, (uintmax_t) features);
127 
128 	for (n = 0, val = 1ULL << 63; val != 0; val >>= 1) {
129 		/*
130 		 * BAD_FEATURE is used to detect broken Linux clients
131 		 * and therefore is not applicable to FreeBSD.
132 		 */
133 		if (((features & val) == 0) || val == VIRTIO_F_BAD_FEATURE)
134 			continue;
135 
136 		if (n++ == 0)
137 			sbuf_cat(&sb, " <");
138 		else
139 			sbuf_cat(&sb, ",");
140 
141 		name = virtio_feature_name(val, desc);
142 		if (name == NULL)
143 			sbuf_printf(&sb, "%#jx", (uintmax_t) val);
144 		else
145 			sbuf_cat(&sb, name);
146 	}
147 
148 	if (n > 0)
149 		sbuf_cat(&sb, ">");
150 
151 #if __FreeBSD_version < 900020
152 	sbuf_finish(&sb);
153 	if (sbuf_overflowed(&sb) == 0)
154 #else
155 	if (sbuf_finish(&sb) == 0)
156 #endif
157 		device_printf(dev, "%s\n", sbuf_data(&sb));
158 
159 	sbuf_delete(&sb);
160 	free(buf, M_TEMP);
161 }
162 
163 /*
164  * VirtIO bus method wrappers.
165  */
166 
167 void
168 virtio_read_ivar(device_t dev, int ivar, uintptr_t *val)
169 {
170 
171 	*val = -1;
172 	BUS_READ_IVAR(device_get_parent(dev), dev, ivar, val);
173 }
174 
175 void
176 virtio_write_ivar(device_t dev, int ivar, uintptr_t val)
177 {
178 
179 	BUS_WRITE_IVAR(device_get_parent(dev), dev, ivar, val);
180 }
181 
182 uint64_t
183 virtio_negotiate_features(device_t dev, uint64_t child_features)
184 {
185 
186 	return (VIRTIO_BUS_NEGOTIATE_FEATURES(device_get_parent(dev),
187 	    child_features));
188 }
189 
190 int
191 virtio_alloc_virtqueues(device_t dev, int flags, int nvqs,
192     struct vq_alloc_info *info)
193 {
194 
195 	return (VIRTIO_BUS_ALLOC_VIRTQUEUES(device_get_parent(dev), flags,
196 	    nvqs, info));
197 }
198 
199 int
200 virtio_setup_intr(device_t dev, enum intr_type type)
201 {
202 
203 	return (VIRTIO_BUS_SETUP_INTR(device_get_parent(dev), type));
204 }
205 
206 int
207 virtio_with_feature(device_t dev, uint64_t feature)
208 {
209 
210 	return (VIRTIO_BUS_WITH_FEATURE(device_get_parent(dev), feature));
211 }
212 
213 void
214 virtio_stop(device_t dev)
215 {
216 
217 	VIRTIO_BUS_STOP(device_get_parent(dev));
218 }
219 
220 int
221 virtio_reinit(device_t dev, uint64_t features)
222 {
223 
224 	return (VIRTIO_BUS_REINIT(device_get_parent(dev), features));
225 }
226 
227 void
228 virtio_reinit_complete(device_t dev)
229 {
230 
231 	VIRTIO_BUS_REINIT_COMPLETE(device_get_parent(dev));
232 }
233 
234 void
235 virtio_read_device_config(device_t dev, bus_size_t offset, void *dst, int len)
236 {
237 
238 	VIRTIO_BUS_READ_DEVICE_CONFIG(device_get_parent(dev),
239 	    offset, dst, len);
240 }
241 
242 void
243 virtio_write_device_config(device_t dev, bus_size_t offset, void *dst, int len)
244 {
245 
246 	VIRTIO_BUS_WRITE_DEVICE_CONFIG(device_get_parent(dev),
247 	    offset, dst, len);
248 }
249 
250 static int
251 virtio_modevent(module_t mod, int type, void *unused)
252 {
253 	int error;
254 
255 	switch (type) {
256 	case MOD_LOAD:
257 	case MOD_QUIESCE:
258 	case MOD_UNLOAD:
259 	case MOD_SHUTDOWN:
260 		error = 0;
261 		break;
262 	default:
263 		error = EOPNOTSUPP;
264 		break;
265 	}
266 
267 	return (error);
268 }
269 
270 static moduledata_t virtio_mod = {
271 	"virtio",
272 	virtio_modevent,
273 	0
274 };
275 
276 DECLARE_MODULE(virtio, virtio_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
277 MODULE_VERSION(virtio, 1);
278