virtio.c revision 330897 
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: stable/11/sys/dev/virtio/virtio.c 330897 2018-03-14 03:19:51Z eadler $");
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
50static int virtio_modevent(module_t, int, void *);
51static const char *virtio_feature_name(uint64_t, struct virtio_feature_desc *);
52
53static 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. */
70static 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
79const char *
80virtio_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
92static const char *
93virtio_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
112void
113virtio_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
169void
170virtio_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
177void
178virtio_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
184uint64_t
185virtio_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
192int
193virtio_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
201int
202virtio_setup_intr(device_t dev, enum intr_type type)
203{
204
205	return (VIRTIO_BUS_SETUP_INTR(device_get_parent(dev), type));
206}
207
208int
209virtio_with_feature(device_t dev, uint64_t feature)
210{
211
212	return (VIRTIO_BUS_WITH_FEATURE(device_get_parent(dev), feature));
213}
214
215void
216virtio_stop(device_t dev)
217{
218
219	VIRTIO_BUS_STOP(device_get_parent(dev));
220}
221
222int
223virtio_reinit(device_t dev, uint64_t features)
224{
225
226	return (VIRTIO_BUS_REINIT(device_get_parent(dev), features));
227}
228
229void
230virtio_reinit_complete(device_t dev)
231{
232
233	VIRTIO_BUS_REINIT_COMPLETE(device_get_parent(dev));
234}
235
236void
237virtio_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
244void
245virtio_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
252static int
253virtio_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
272static moduledata_t virtio_mod = {
273	"virtio",
274	virtio_modevent,
275	0
276};
277
278DECLARE_MODULE(virtio, virtio_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
279MODULE_VERSION(virtio, 1);
280