xref: /freebsd/sys/dev/virtio/virtio.c (revision 1603881667360c015f6685131f2f25474fa67a72)
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("$FreeBSD$");
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 
50 static int virtio_modevent(module_t, int, void *);
51 static const char *virtio_feature_name(uint64_t, struct virtio_feature_desc *);
52 
53 static 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_RPMSG,		"Remote Processor Messaging"	},
64 	{ VIRTIO_ID_SCSI,		"SCSI"				},
65 	{ VIRTIO_ID_9P,			"9P Transport"			},
66 	{ VIRTIO_ID_RPROC_SERIAL,	"Remote Processor Serial"	},
67 	{ VIRTIO_ID_CAIF,		"CAIF"				},
68 	{ VIRTIO_ID_GPU,		"GPU"				},
69 	{ VIRTIO_ID_INPUT,		"Input"				},
70 	{ VIRTIO_ID_VSOCK,		"VSOCK Transport"		},
71 	{ VIRTIO_ID_CRYPTO,		"Crypto"			},
72 
73 	{ 0, NULL }
74 };
75 
76 /* Device independent features. */
77 static struct virtio_feature_desc virtio_common_feature_desc[] = {
78 	{ VIRTIO_F_NOTIFY_ON_EMPTY,	"NotifyOnEmpty"		}, /* Legacy */
79 	{ VIRTIO_F_ANY_LAYOUT,		"AnyLayout"		}, /* Legacy */
80 	{ VIRTIO_RING_F_INDIRECT_DESC,	"RingIndirectDesc"	},
81 	{ VIRTIO_RING_F_EVENT_IDX,	"RingEventIdx"		},
82 	{ VIRTIO_F_BAD_FEATURE,		"BadFeature"		}, /* Legacy */
83 	{ VIRTIO_F_VERSION_1,		"Version1"		},
84 	{ VIRTIO_F_IOMMU_PLATFORM,	"IOMMUPlatform"		},
85 
86 	{ 0, NULL }
87 };
88 
89 const char *
90 virtio_device_name(uint16_t devid)
91 {
92 	struct virtio_ident *ident;
93 
94 	for (ident = virtio_ident_table; ident->name != NULL; ident++) {
95 		if (ident->devid == devid)
96 			return (ident->name);
97 	}
98 
99 	return (NULL);
100 }
101 
102 static const char *
103 virtio_feature_name(uint64_t val, struct virtio_feature_desc *desc)
104 {
105 	int i, j;
106 	struct virtio_feature_desc *descs[2] = { desc,
107 	    virtio_common_feature_desc };
108 
109 	for (i = 0; i < 2; i++) {
110 		if (descs[i] == NULL)
111 			continue;
112 
113 		for (j = 0; descs[i][j].vfd_val != 0; j++) {
114 			if (val == descs[i][j].vfd_val)
115 				return (descs[i][j].vfd_str);
116 		}
117 	}
118 
119 	return (NULL);
120 }
121 
122 int
123 virtio_describe_sbuf(struct sbuf *sb, uint64_t features,
124     struct virtio_feature_desc *desc)
125 {
126 	const char *name;
127 	uint64_t val;
128 	int n;
129 
130 	sbuf_printf(sb, "%#jx", (uintmax_t) features);
131 
132 	for (n = 0, val = 1ULL << 63; val != 0; val >>= 1) {
133 		/*
134 		 * BAD_FEATURE is used to detect broken Linux clients
135 		 * and therefore is not applicable to FreeBSD.
136 		 */
137 		if (((features & val) == 0) || val == VIRTIO_F_BAD_FEATURE)
138 			continue;
139 
140 		if (n++ == 0)
141 			sbuf_cat(sb, " <");
142 		else
143 			sbuf_cat(sb, ",");
144 
145 		name = virtio_feature_name(val, desc);
146 		if (name == NULL)
147 			sbuf_printf(sb, "%#jx", (uintmax_t) val);
148 		else
149 			sbuf_cat(sb, name);
150 	}
151 
152 	if (n > 0)
153 		sbuf_cat(sb, ">");
154 
155 	return (sbuf_finish(sb));
156 }
157 
158 void
159 virtio_describe(device_t dev, const char *msg, uint64_t features,
160     struct virtio_feature_desc *desc)
161 {
162 	struct sbuf sb;
163 	char *buf;
164 	int error;
165 
166 	if ((buf = malloc(1024, M_TEMP, M_NOWAIT)) == NULL) {
167 		error = ENOMEM;
168 		goto out;
169 	}
170 
171 	sbuf_new(&sb, buf, 1024, SBUF_FIXEDLEN);
172 	sbuf_printf(&sb, "%s features: ", msg);
173 
174 	error = virtio_describe_sbuf(&sb, features, desc);
175 	if (error == 0)
176 		device_printf(dev, "%s\n", sbuf_data(&sb));
177 
178 	sbuf_delete(&sb);
179 	free(buf, M_TEMP);
180 
181 out:
182 	if (error != 0) {
183 		device_printf(dev, "%s features: %#jx\n", msg,
184 		    (uintmax_t) features);
185 	}
186 }
187 
188 uint64_t
189 virtio_filter_transport_features(uint64_t features)
190 {
191 	uint64_t transport, mask;
192 
193 	transport = (1ULL <<
194 	    (VIRTIO_TRANSPORT_F_END - VIRTIO_TRANSPORT_F_START)) - 1;
195 	transport <<= VIRTIO_TRANSPORT_F_START;
196 
197 	mask = -1ULL & ~transport;
198 	mask |= VIRTIO_RING_F_INDIRECT_DESC;
199 	mask |= VIRTIO_RING_F_EVENT_IDX;
200 	mask |= VIRTIO_F_VERSION_1;
201 
202 	return (features & mask);
203 }
204 
205 int
206 virtio_bus_is_modern(device_t dev)
207 {
208 	uintptr_t modern;
209 
210 	virtio_read_ivar(dev, VIRTIO_IVAR_MODERN, &modern);
211 	return (modern != 0);
212 }
213 
214 void
215 virtio_read_device_config_array(device_t dev, bus_size_t offset, void *dst,
216     int size, int count)
217 {
218 	int i, gen;
219 
220 	do {
221 		gen = virtio_config_generation(dev);
222 
223 		for (i = 0; i < count; i++) {
224 			virtio_read_device_config(dev, offset + i * size,
225 			    (uint8_t *) dst + i * size, size);
226 		}
227 	} while (gen != virtio_config_generation(dev));
228 }
229 
230 /*
231  * VirtIO bus method wrappers.
232  */
233 
234 void
235 virtio_read_ivar(device_t dev, int ivar, uintptr_t *val)
236 {
237 
238 	*val = -1;
239 	BUS_READ_IVAR(device_get_parent(dev), dev, ivar, val);
240 }
241 
242 void
243 virtio_write_ivar(device_t dev, int ivar, uintptr_t val)
244 {
245 
246 	BUS_WRITE_IVAR(device_get_parent(dev), dev, ivar, val);
247 }
248 
249 uint64_t
250 virtio_negotiate_features(device_t dev, uint64_t child_features)
251 {
252 
253 	return (VIRTIO_BUS_NEGOTIATE_FEATURES(device_get_parent(dev),
254 	    child_features));
255 }
256 
257 int
258 virtio_finalize_features(device_t dev)
259 {
260 
261 	return (VIRTIO_BUS_FINALIZE_FEATURES(device_get_parent(dev)));
262 }
263 
264 int
265 virtio_alloc_virtqueues(device_t dev, int flags, int nvqs,
266     struct vq_alloc_info *info)
267 {
268 
269 	return (VIRTIO_BUS_ALLOC_VIRTQUEUES(device_get_parent(dev), flags,
270 	    nvqs, info));
271 }
272 
273 int
274 virtio_setup_intr(device_t dev, enum intr_type type)
275 {
276 
277 	return (VIRTIO_BUS_SETUP_INTR(device_get_parent(dev), type));
278 }
279 
280 int
281 virtio_with_feature(device_t dev, uint64_t feature)
282 {
283 
284 	return (VIRTIO_BUS_WITH_FEATURE(device_get_parent(dev), feature));
285 }
286 
287 void
288 virtio_stop(device_t dev)
289 {
290 
291 	VIRTIO_BUS_STOP(device_get_parent(dev));
292 }
293 
294 int
295 virtio_reinit(device_t dev, uint64_t features)
296 {
297 
298 	return (VIRTIO_BUS_REINIT(device_get_parent(dev), features));
299 }
300 
301 void
302 virtio_reinit_complete(device_t dev)
303 {
304 
305 	VIRTIO_BUS_REINIT_COMPLETE(device_get_parent(dev));
306 }
307 
308 int
309 virtio_config_generation(device_t dev)
310 {
311 
312 	return (VIRTIO_BUS_CONFIG_GENERATION(device_get_parent(dev)));
313 }
314 
315 void
316 virtio_read_device_config(device_t dev, bus_size_t offset, void *dst, int len)
317 {
318 
319 	VIRTIO_BUS_READ_DEVICE_CONFIG(device_get_parent(dev),
320 	    offset, dst, len);
321 }
322 
323 void
324 virtio_write_device_config(device_t dev, bus_size_t offset, void *dst, int len)
325 {
326 
327 	VIRTIO_BUS_WRITE_DEVICE_CONFIG(device_get_parent(dev),
328 	    offset, dst, len);
329 }
330 
331 int
332 virtio_child_pnpinfo_str(device_t busdev __unused, device_t child, char *buf,
333     size_t buflen)
334 {
335 
336 	/*
337 	 * All of these PCI fields will be only 16 bits, but on the vtmmio bus
338 	 * the corresponding fields (only "vendor" and "device_type") are 32
339 	 * bits.  Many virtio drivers can attach below either bus.
340 	 * Gratuitously expand these two fields to 32-bits to allow sharing PNP
341 	 * match table data between the mostly-similar buses.
342 	 *
343 	 * Subdevice and device_type are redundant in both buses, so I don't
344 	 * see a lot of PNP utility in exposing the same value under a
345 	 * different name.
346 	 */
347 	snprintf(buf, buflen, "vendor=0x%08x device=0x%04x subvendor=0x%04x "
348 	    "device_type=0x%08x", (unsigned)virtio_get_vendor(child),
349 	    (unsigned)virtio_get_device(child),
350 	    (unsigned)virtio_get_subvendor(child),
351 	    (unsigned)virtio_get_device_type(child));
352 	return (0);
353 }
354 
355 static int
356 virtio_modevent(module_t mod, int type, void *unused)
357 {
358 	int error;
359 
360 	switch (type) {
361 	case MOD_LOAD:
362 	case MOD_QUIESCE:
363 	case MOD_UNLOAD:
364 	case MOD_SHUTDOWN:
365 		error = 0;
366 		break;
367 	default:
368 		error = EOPNOTSUPP;
369 		break;
370 	}
371 
372 	return (error);
373 }
374 
375 static moduledata_t virtio_mod = {
376 	"virtio",
377 	virtio_modevent,
378 	0
379 };
380 
381 DECLARE_MODULE(virtio, virtio_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
382 MODULE_VERSION(virtio, 1);
383