xref: /freebsd/sys/dev/virtio/virtio.c (revision bc531a96c9b28b1cabcd5deb0c9f8f6d815cfebc)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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/param.h>
30 #include <sys/systm.h>
31 #include <sys/kernel.h>
32 #include <sys/malloc.h>
33 #include <sys/sysctl.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/virtio_config.h>
44 #include <dev/virtio/virtqueue.h>
45 
46 #include "virtio_bus_if.h"
47 
48 static int virtio_modevent(module_t, int, void *);
49 static const char *virtio_feature_name(uint64_t, struct virtio_feature_desc *);
50 
51 static struct virtio_ident {
52 	uint16_t	devid;
53 	const 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_RPMSG,		"Remote Processor Messaging"	},
62 	{ VIRTIO_ID_SCSI,		"SCSI"				},
63 	{ VIRTIO_ID_9P,			"9P Transport"			},
64 	{ VIRTIO_ID_RPROC_SERIAL,	"Remote Processor Serial"	},
65 	{ VIRTIO_ID_CAIF,		"CAIF"				},
66 	{ VIRTIO_ID_GPU,		"GPU"				},
67 	{ VIRTIO_ID_INPUT,		"Input"				},
68 	{ VIRTIO_ID_VSOCK,		"VSOCK Transport"		},
69 	{ VIRTIO_ID_CRYPTO,		"Crypto"			},
70 	{ VIRTIO_ID_IOMMU,		"IOMMU"				},
71 	{ VIRTIO_ID_SOUND,		"Sound"				},
72 	{ VIRTIO_ID_FS,			"Filesystem"			},
73 	{ VIRTIO_ID_PMEM,		"Persistent Memory"		},
74 	{ VIRTIO_ID_RPMB,		"RPMB"				},
75 	{ VIRTIO_ID_SCMI,		"SCMI"				},
76 	{ VIRTIO_ID_GPIO,		"GPIO"				},
77 
78 	{ 0, NULL }
79 };
80 
81 /* Device independent features. */
82 static struct virtio_feature_desc virtio_common_feature_desc[] = {
83 	{ VIRTIO_F_NOTIFY_ON_EMPTY,	"NotifyOnEmpty"		}, /* Legacy */
84 	{ VIRTIO_F_ANY_LAYOUT,		"AnyLayout"		}, /* Legacy */
85 	{ VIRTIO_RING_F_INDIRECT_DESC,	"RingIndirectDesc"	},
86 	{ VIRTIO_RING_F_EVENT_IDX,	"RingEventIdx"		},
87 	{ VIRTIO_F_BAD_FEATURE,		"BadFeature"		}, /* Legacy */
88 	{ VIRTIO_F_VERSION_1,		"Version1"		},
89 	{ VIRTIO_F_IOMMU_PLATFORM,	"IOMMUPlatform"		},
90 
91 	{ 0, NULL }
92 };
93 
94 SYSCTL_NODE(_hw, OID_AUTO, virtio, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
95     "VirtIO driver parameters");
96 
97 const char *
98 virtio_device_name(uint16_t devid)
99 {
100 	struct virtio_ident *ident;
101 
102 	for (ident = virtio_ident_table; ident->name != NULL; ident++) {
103 		if (ident->devid == devid)
104 			return (ident->name);
105 	}
106 
107 	return (NULL);
108 }
109 
110 static const char *
111 virtio_feature_name(uint64_t val, struct virtio_feature_desc *desc)
112 {
113 	int i, j;
114 	struct virtio_feature_desc *descs[2] = { desc,
115 	    virtio_common_feature_desc };
116 
117 	for (i = 0; i < 2; i++) {
118 		if (descs[i] == NULL)
119 			continue;
120 
121 		for (j = 0; descs[i][j].vfd_val != 0; j++) {
122 			if (val == descs[i][j].vfd_val)
123 				return (descs[i][j].vfd_str);
124 		}
125 	}
126 
127 	return (NULL);
128 }
129 
130 int
131 virtio_describe_sbuf(struct sbuf *sb, uint64_t features,
132     struct virtio_feature_desc *desc)
133 {
134 	const char *name;
135 	uint64_t val;
136 	int n;
137 
138 	sbuf_printf(sb, "%#jx", (uintmax_t) features);
139 
140 	for (n = 0, val = 1ULL << 63; val != 0; val >>= 1) {
141 		/*
142 		 * BAD_FEATURE is used to detect broken Linux clients
143 		 * and therefore is not applicable to FreeBSD.
144 		 */
145 		if (((features & val) == 0) || val == VIRTIO_F_BAD_FEATURE)
146 			continue;
147 
148 		if (n++ == 0)
149 			sbuf_cat(sb, " <");
150 		else
151 			sbuf_cat(sb, ",");
152 
153 		name = virtio_feature_name(val, desc);
154 		if (name == NULL)
155 			sbuf_printf(sb, "%#jx", (uintmax_t) val);
156 		else
157 			sbuf_cat(sb, name);
158 	}
159 
160 	if (n > 0)
161 		sbuf_cat(sb, ">");
162 
163 	return (sbuf_finish(sb));
164 }
165 
166 void
167 virtio_describe(device_t dev, const char *msg, uint64_t features,
168     struct virtio_feature_desc *desc)
169 {
170 	struct sbuf sb;
171 	char *buf;
172 	int error;
173 
174 	if ((buf = malloc(1024, M_TEMP, M_NOWAIT)) == NULL) {
175 		error = ENOMEM;
176 		goto out;
177 	}
178 
179 	sbuf_new(&sb, buf, 1024, SBUF_FIXEDLEN);
180 	sbuf_printf(&sb, "%s features: ", msg);
181 
182 	error = virtio_describe_sbuf(&sb, features, desc);
183 	if (error == 0)
184 		device_printf(dev, "%s\n", sbuf_data(&sb));
185 
186 	sbuf_delete(&sb);
187 	free(buf, M_TEMP);
188 
189 out:
190 	if (error != 0) {
191 		device_printf(dev, "%s features: %#jx\n", msg,
192 		    (uintmax_t) features);
193 	}
194 }
195 
196 uint64_t
197 virtio_filter_transport_features(uint64_t features)
198 {
199 	uint64_t transport, mask;
200 
201 	transport = (1ULL <<
202 	    (VIRTIO_TRANSPORT_F_END - VIRTIO_TRANSPORT_F_START)) - 1;
203 	transport <<= VIRTIO_TRANSPORT_F_START;
204 
205 	mask = -1ULL & ~transport;
206 	mask |= VIRTIO_RING_F_INDIRECT_DESC;
207 	mask |= VIRTIO_RING_F_EVENT_IDX;
208 	mask |= VIRTIO_F_VERSION_1;
209 
210 	return (features & mask);
211 }
212 
213 bool
214 virtio_bus_is_modern(device_t dev)
215 {
216 	uintptr_t modern;
217 
218 	virtio_read_ivar(dev, VIRTIO_IVAR_MODERN, &modern);
219 	return (modern != 0);
220 }
221 
222 void
223 virtio_read_device_config_array(device_t dev, bus_size_t offset, void *dst,
224     int size, int count)
225 {
226 	int i, gen;
227 
228 	do {
229 		gen = virtio_config_generation(dev);
230 
231 		for (i = 0; i < count; i++) {
232 			virtio_read_device_config(dev, offset + i * size,
233 			    (uint8_t *) dst + i * size, size);
234 		}
235 	} while (gen != virtio_config_generation(dev));
236 }
237 
238 /*
239  * VirtIO bus method wrappers.
240  */
241 
242 void
243 virtio_read_ivar(device_t dev, int ivar, uintptr_t *val)
244 {
245 
246 	*val = -1;
247 	BUS_READ_IVAR(device_get_parent(dev), dev, ivar, val);
248 }
249 
250 void
251 virtio_write_ivar(device_t dev, int ivar, uintptr_t val)
252 {
253 
254 	BUS_WRITE_IVAR(device_get_parent(dev), dev, ivar, val);
255 }
256 
257 uint64_t
258 virtio_negotiate_features(device_t dev, uint64_t child_features)
259 {
260 
261 	return (VIRTIO_BUS_NEGOTIATE_FEATURES(device_get_parent(dev),
262 	    child_features));
263 }
264 
265 int
266 virtio_finalize_features(device_t dev)
267 {
268 
269 	return (VIRTIO_BUS_FINALIZE_FEATURES(device_get_parent(dev)));
270 }
271 
272 int
273 virtio_alloc_virtqueues(device_t dev, int nvqs,
274     struct vq_alloc_info *info)
275 {
276 
277 	return (VIRTIO_BUS_ALLOC_VIRTQUEUES(device_get_parent(dev), nvqs, info));
278 }
279 
280 int
281 virtio_setup_intr(device_t dev, enum intr_type type)
282 {
283 
284 	return (VIRTIO_BUS_SETUP_INTR(device_get_parent(dev), type));
285 }
286 
287 bool
288 virtio_with_feature(device_t dev, uint64_t feature)
289 {
290 
291 	return (VIRTIO_BUS_WITH_FEATURE(device_get_parent(dev), feature));
292 }
293 
294 void
295 virtio_stop(device_t dev)
296 {
297 
298 	VIRTIO_BUS_STOP(device_get_parent(dev));
299 }
300 
301 int
302 virtio_reinit(device_t dev, uint64_t features)
303 {
304 
305 	return (VIRTIO_BUS_REINIT(device_get_parent(dev), features));
306 }
307 
308 void
309 virtio_reinit_complete(device_t dev)
310 {
311 
312 	VIRTIO_BUS_REINIT_COMPLETE(device_get_parent(dev));
313 }
314 
315 int
316 virtio_config_generation(device_t dev)
317 {
318 
319 	return (VIRTIO_BUS_CONFIG_GENERATION(device_get_parent(dev)));
320 }
321 
322 void
323 virtio_read_device_config(device_t dev, bus_size_t offset, void *dst, int len)
324 {
325 
326 	VIRTIO_BUS_READ_DEVICE_CONFIG(device_get_parent(dev),
327 	    offset, dst, len);
328 }
329 
330 void
331 virtio_write_device_config(device_t dev, bus_size_t offset, const void *dst, int len)
332 {
333 
334 	VIRTIO_BUS_WRITE_DEVICE_CONFIG(device_get_parent(dev),
335 	    offset, dst, len);
336 }
337 
338 int
339 virtio_child_pnpinfo(device_t busdev __unused, device_t child, struct sbuf *sb)
340 {
341 
342 	/*
343 	 * All of these PCI fields will be only 16 bits, but on the vtmmio bus
344 	 * the corresponding fields (only "vendor" and "device_type") are 32
345 	 * bits.  Many virtio drivers can attach below either bus.
346 	 * Gratuitously expand these two fields to 32-bits to allow sharing PNP
347 	 * match table data between the mostly-similar buses.
348 	 *
349 	 * Subdevice and device_type are redundant in both buses, so I don't
350 	 * see a lot of PNP utility in exposing the same value under a
351 	 * different name.
352 	 */
353 	sbuf_printf(sb, "vendor=0x%08x device=0x%04x subvendor=0x%04x "
354 	    "device_type=0x%08x", (unsigned)virtio_get_vendor(child),
355 	    (unsigned)virtio_get_device(child),
356 	    (unsigned)virtio_get_subvendor(child),
357 	    (unsigned)virtio_get_device_type(child));
358 	return (0);
359 }
360 
361 static int
362 virtio_modevent(module_t mod, int type, void *unused)
363 {
364 	int error;
365 
366 	switch (type) {
367 	case MOD_LOAD:
368 	case MOD_QUIESCE:
369 	case MOD_UNLOAD:
370 	case MOD_SHUTDOWN:
371 		error = 0;
372 		break;
373 	default:
374 		error = EOPNOTSUPP;
375 		break;
376 	}
377 
378 	return (error);
379 }
380 
381 static moduledata_t virtio_mod = {
382 	"virtio",
383 	virtio_modevent,
384 	0
385 };
386 
387 DECLARE_MODULE(virtio, virtio_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
388 MODULE_VERSION(virtio, 1);
389