virtio.c revision 227652 
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: head/sys/dev/virtio/virtio.c 227652 2011-11-18 05:43:43Z grehan $");
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
48static int virtio_modevent(module_t, int, void *);
49static const char *virtio_feature_name(uint64_t, struct virtio_feature_desc *);
50
51static 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. */
67static 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
76const char *
77virtio_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
89int
90virtio_get_device_type(device_t dev)
91{
92	uintptr_t devtype;
93
94	devtype = -1;
95
96	BUS_READ_IVAR(device_get_parent(dev), dev,
97	    VIRTIO_IVAR_DEVTYPE, &devtype);
98
99	return ((int) devtype);
100}
101
102void
103virtio_set_feature_desc(device_t dev,
104    struct virtio_feature_desc *feature_desc)
105{
106
107	BUS_WRITE_IVAR(device_get_parent(dev), dev,
108	    VIRTIO_IVAR_FEATURE_DESC, (uintptr_t) feature_desc);
109}
110
111void
112virtio_describe(device_t dev, const char *msg,
113    uint64_t features, struct virtio_feature_desc *feature_desc)
114{
115	struct sbuf sb;
116	uint64_t val;
117	char *buf;
118	const char *name;
119	int n;
120
121	if ((buf = malloc(512, M_TEMP, M_NOWAIT)) == NULL) {
122		device_printf(dev, "%s features: 0x%"PRIx64"\n", msg,
123		    features);
124		return;
125	}
126
127	sbuf_new(&sb, buf, 512, SBUF_FIXEDLEN);
128	sbuf_printf(&sb, "%s features: 0x%"PRIx64, msg, 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 = NULL;
144		if (feature_desc != NULL)
145			name = virtio_feature_name(val, feature_desc);
146		if (name == NULL)
147			name = virtio_feature_name(val,
148			    virtio_common_feature_desc);
149
150		if (name == NULL)
151			sbuf_printf(&sb, "0x%"PRIx64, val);
152		else
153			sbuf_cat(&sb, name);
154	}
155
156	if (n > 0)
157		sbuf_cat(&sb, ">");
158
159#if __FreeBSD_version < 900020
160	sbuf_finish(&sb);
161	if (sbuf_overflowed(&sb) == 0)
162#else
163	if (sbuf_finish(&sb) == 0)
164#endif
165		device_printf(dev, "%s\n", sbuf_data(&sb));
166
167	sbuf_delete(&sb);
168	free(buf, M_TEMP);
169}
170
171static const char *
172virtio_feature_name(uint64_t val, struct virtio_feature_desc *feature_desc)
173{
174	int i;
175
176	for (i = 0; feature_desc[i].vfd_val != 0; i++)
177		if (val == feature_desc[i].vfd_val)
178			return (feature_desc[i].vfd_str);
179
180	return (NULL);
181}
182
183/*
184 * VirtIO bus method wrappers.
185 */
186
187uint64_t
188virtio_negotiate_features(device_t dev, uint64_t child_features)
189{
190
191	return (VIRTIO_BUS_NEGOTIATE_FEATURES(device_get_parent(dev),
192	    child_features));
193}
194
195int
196virtio_alloc_virtqueues(device_t dev, int flags, int nvqs,
197    struct vq_alloc_info *info)
198{
199
200	return (VIRTIO_BUS_ALLOC_VIRTQUEUES(device_get_parent(dev), flags,
201	    nvqs, info));
202}
203
204int
205virtio_setup_intr(device_t dev, enum intr_type type)
206{
207
208	return (VIRTIO_BUS_SETUP_INTR(device_get_parent(dev), type));
209}
210
211int
212virtio_with_feature(device_t dev, uint64_t feature)
213{
214
215	return (VIRTIO_BUS_WITH_FEATURE(device_get_parent(dev), feature));
216}
217
218void
219virtio_stop(device_t dev)
220{
221
222	VIRTIO_BUS_STOP(device_get_parent(dev));
223}
224
225int
226virtio_reinit(device_t dev, uint64_t features)
227{
228
229	return (VIRTIO_BUS_REINIT(device_get_parent(dev), features));
230}
231
232void
233virtio_reinit_complete(device_t dev)
234{
235
236	VIRTIO_BUS_REINIT_COMPLETE(device_get_parent(dev));
237}
238
239void
240virtio_read_device_config(device_t dev, bus_size_t offset, void *dst, int len)
241{
242
243	VIRTIO_BUS_READ_DEVICE_CONFIG(device_get_parent(dev),
244	    offset, dst, len);
245}
246
247void
248virtio_write_device_config(device_t dev, bus_size_t offset, void *dst, int len)
249{
250
251	VIRTIO_BUS_WRITE_DEVICE_CONFIG(device_get_parent(dev),
252	    offset, dst, len);
253}
254
255static int
256virtio_modevent(module_t mod, int type, void *unused)
257{
258	int error;
259
260	error = 0;
261
262	switch (type) {
263	case MOD_LOAD:
264	case MOD_QUIESCE:
265	case MOD_UNLOAD:
266	case MOD_SHUTDOWN:
267		break;
268	default:
269		error = EOPNOTSUPP;
270		break;
271	}
272
273	return (error);
274}
275
276static moduledata_t virtio_mod = {
277	"virtio",
278	virtio_modevent,
279	0
280};
281
282DECLARE_MODULE(virtio, virtio_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
283MODULE_VERSION(virtio, 1);
284