xref: /freebsd/sys/dev/virtio/virtio.c (revision 38f0b757fd84d17d0fc24739a7cda160c4516d81)
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/virtqueue.h>
44 
45 #include "virtio_bus_if.h"
46 
47 static int virtio_modevent(module_t, int, void *);
48 static const char *virtio_feature_name(uint64_t, struct virtio_feature_desc *);
49 
50 static struct virtio_ident {
51 	uint16_t	devid;
52 	const char	*name;
53 } virtio_ident_table[] = {
54 	{ VIRTIO_ID_NETWORK,	"Network"	},
55 	{ VIRTIO_ID_BLOCK,	"Block"		},
56 	{ VIRTIO_ID_CONSOLE,	"Console"	},
57 	{ VIRTIO_ID_ENTROPY,	"Entropy"	},
58 	{ VIRTIO_ID_BALLOON,	"Balloon"	},
59 	{ VIRTIO_ID_IOMEMORY,	"IOMemory"	},
60 	{ VIRTIO_ID_SCSI,	"SCSI"		},
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 static const char *
90 virtio_feature_name(uint64_t val, struct virtio_feature_desc *desc)
91 {
92 	int i, j;
93 	struct virtio_feature_desc *descs[2] = { desc,
94 	    virtio_common_feature_desc };
95 
96 	for (i = 0; i < 2; i++) {
97 		if (descs[i] == NULL)
98 			continue;
99 
100 		for (j = 0; descs[i][j].vfd_val != 0; j++) {
101 			if (val == descs[i][j].vfd_val)
102 				return (descs[i][j].vfd_str);
103 		}
104 	}
105 
106 	return (NULL);
107 }
108 
109 void
110 virtio_describe(device_t dev, const char *msg,
111     uint64_t features, struct virtio_feature_desc *desc)
112 {
113 	struct sbuf sb;
114 	uint64_t val;
115 	char *buf;
116 	const char *name;
117 	int n;
118 
119 	if ((buf = malloc(512, M_TEMP, M_NOWAIT)) == NULL) {
120 		device_printf(dev, "%s features: %#jx\n", msg, (uintmax_t) features);
121 		return;
122 	}
123 
124 	sbuf_new(&sb, buf, 512, SBUF_FIXEDLEN);
125 	sbuf_printf(&sb, "%s features: %#jx", msg, (uintmax_t) features);
126 
127 	for (n = 0, val = 1ULL << 63; val != 0; val >>= 1) {
128 		/*
129 		 * BAD_FEATURE is used to detect broken Linux clients
130 		 * and therefore is not applicable to FreeBSD.
131 		 */
132 		if (((features & val) == 0) || val == VIRTIO_F_BAD_FEATURE)
133 			continue;
134 
135 		if (n++ == 0)
136 			sbuf_cat(&sb, " <");
137 		else
138 			sbuf_cat(&sb, ",");
139 
140 		name = virtio_feature_name(val, desc);
141 		if (name == NULL)
142 			sbuf_printf(&sb, "%#jx", (uintmax_t) val);
143 		else
144 			sbuf_cat(&sb, name);
145 	}
146 
147 	if (n > 0)
148 		sbuf_cat(&sb, ">");
149 
150 #if __FreeBSD_version < 900020
151 	sbuf_finish(&sb);
152 	if (sbuf_overflowed(&sb) == 0)
153 #else
154 	if (sbuf_finish(&sb) == 0)
155 #endif
156 		device_printf(dev, "%s\n", sbuf_data(&sb));
157 
158 	sbuf_delete(&sb);
159 	free(buf, M_TEMP);
160 }
161 
162 /*
163  * VirtIO bus method wrappers.
164  */
165 
166 void
167 virtio_read_ivar(device_t dev, int ivar, uintptr_t *val)
168 {
169 
170 	*val = -1;
171 	BUS_READ_IVAR(device_get_parent(dev), dev, ivar, val);
172 }
173 
174 void
175 virtio_write_ivar(device_t dev, int ivar, uintptr_t val)
176 {
177 
178 	BUS_WRITE_IVAR(device_get_parent(dev), dev, ivar, val);
179 }
180 
181 uint64_t
182 virtio_negotiate_features(device_t dev, uint64_t child_features)
183 {
184 
185 	return (VIRTIO_BUS_NEGOTIATE_FEATURES(device_get_parent(dev),
186 	    child_features));
187 }
188 
189 int
190 virtio_alloc_virtqueues(device_t dev, int flags, int nvqs,
191     struct vq_alloc_info *info)
192 {
193 
194 	return (VIRTIO_BUS_ALLOC_VIRTQUEUES(device_get_parent(dev), flags,
195 	    nvqs, info));
196 }
197 
198 int
199 virtio_setup_intr(device_t dev, enum intr_type type)
200 {
201 
202 	return (VIRTIO_BUS_SETUP_INTR(device_get_parent(dev), type));
203 }
204 
205 int
206 virtio_with_feature(device_t dev, uint64_t feature)
207 {
208 
209 	return (VIRTIO_BUS_WITH_FEATURE(device_get_parent(dev), feature));
210 }
211 
212 void
213 virtio_stop(device_t dev)
214 {
215 
216 	VIRTIO_BUS_STOP(device_get_parent(dev));
217 }
218 
219 int
220 virtio_reinit(device_t dev, uint64_t features)
221 {
222 
223 	return (VIRTIO_BUS_REINIT(device_get_parent(dev), features));
224 }
225 
226 void
227 virtio_reinit_complete(device_t dev)
228 {
229 
230 	VIRTIO_BUS_REINIT_COMPLETE(device_get_parent(dev));
231 }
232 
233 void
234 virtio_read_device_config(device_t dev, bus_size_t offset, void *dst, int len)
235 {
236 
237 	VIRTIO_BUS_READ_DEVICE_CONFIG(device_get_parent(dev),
238 	    offset, dst, len);
239 }
240 
241 void
242 virtio_write_device_config(device_t dev, bus_size_t offset, void *dst, int len)
243 {
244 
245 	VIRTIO_BUS_WRITE_DEVICE_CONFIG(device_get_parent(dev),
246 	    offset, dst, len);
247 }
248 
249 static int
250 virtio_modevent(module_t mod, int type, void *unused)
251 {
252 	int error;
253 
254 	switch (type) {
255 	case MOD_LOAD:
256 	case MOD_QUIESCE:
257 	case MOD_UNLOAD:
258 	case MOD_SHUTDOWN:
259 		error = 0;
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