virtio.c revision 238360 
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 238360 2012-07-11 02:57:19Z 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
89void
90virtio_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
149static const char *
150virtio_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
165void
166virtio_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
173void
174virtio_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
180uint64_t
181virtio_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
188int
189virtio_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
197int
198virtio_setup_intr(device_t dev, enum intr_type type)
199{
200
201	return (VIRTIO_BUS_SETUP_INTR(device_get_parent(dev), type));
202}
203
204int
205virtio_with_feature(device_t dev, uint64_t feature)
206{
207
208	return (VIRTIO_BUS_WITH_FEATURE(device_get_parent(dev), feature));
209}
210
211void
212virtio_stop(device_t dev)
213{
214
215	VIRTIO_BUS_STOP(device_get_parent(dev));
216}
217
218int
219virtio_reinit(device_t dev, uint64_t features)
220{
221
222	return (VIRTIO_BUS_REINIT(device_get_parent(dev), features));
223}
224
225void
226virtio_reinit_complete(device_t dev)
227{
228
229	VIRTIO_BUS_REINIT_COMPLETE(device_get_parent(dev));
230}
231
232void
233virtio_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
240void
241virtio_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
248static int
249virtio_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
269static moduledata_t virtio_mod = {
270	"virtio",
271	virtio_modevent,
272	0
273};
274
275DECLARE_MODULE(virtio, virtio_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
276MODULE_VERSION(virtio, 1);
277