xref: /dpdk/drivers/net/virtio/virtio_user/virtio_user_dev.c (revision 08aa6271c86a561b66c6dd91f9a54fa2f12bc859)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright(c) 2010-2016 Intel Corporation
3  */
4 
5 #include <stdint.h>
6 #include <stdio.h>
7 #include <fcntl.h>
8 #include <string.h>
9 #include <errno.h>
10 #include <sys/mman.h>
11 #include <unistd.h>
12 #include <sys/eventfd.h>
13 #include <sys/types.h>
14 #include <sys/stat.h>
15 
16 #include "vhost.h"
17 #include "virtio_user_dev.h"
18 #include "../virtio_ethdev.h"
19 
20 #define VIRTIO_USER_MEM_EVENT_CLB_NAME "virtio_user_mem_event_clb"
21 
22 static int
23 virtio_user_create_queue(struct virtio_user_dev *dev, uint32_t queue_sel)
24 {
25 	/* Of all per virtqueue MSGs, make sure VHOST_SET_VRING_CALL come
26 	 * firstly because vhost depends on this msg to allocate virtqueue
27 	 * pair.
28 	 */
29 	struct vhost_vring_file file;
30 
31 	file.index = queue_sel;
32 	file.fd = dev->callfds[queue_sel];
33 	dev->ops->send_request(dev, VHOST_USER_SET_VRING_CALL, &file);
34 
35 	return 0;
36 }
37 
38 static int
39 virtio_user_kick_queue(struct virtio_user_dev *dev, uint32_t queue_sel)
40 {
41 	struct vhost_vring_file file;
42 	struct vhost_vring_state state;
43 	struct vring *vring = &dev->vrings[queue_sel];
44 	struct vhost_vring_addr addr = {
45 		.index = queue_sel,
46 		.desc_user_addr = (uint64_t)(uintptr_t)vring->desc,
47 		.avail_user_addr = (uint64_t)(uintptr_t)vring->avail,
48 		.used_user_addr = (uint64_t)(uintptr_t)vring->used,
49 		.log_guest_addr = 0,
50 		.flags = 0, /* disable log */
51 	};
52 
53 	state.index = queue_sel;
54 	state.num = vring->num;
55 	dev->ops->send_request(dev, VHOST_USER_SET_VRING_NUM, &state);
56 
57 	state.index = queue_sel;
58 	state.num = 0; /* no reservation */
59 	dev->ops->send_request(dev, VHOST_USER_SET_VRING_BASE, &state);
60 
61 	dev->ops->send_request(dev, VHOST_USER_SET_VRING_ADDR, &addr);
62 
63 	/* Of all per virtqueue MSGs, make sure VHOST_USER_SET_VRING_KICK comes
64 	 * lastly because vhost depends on this msg to judge if
65 	 * virtio is ready.
66 	 */
67 	file.index = queue_sel;
68 	file.fd = dev->kickfds[queue_sel];
69 	dev->ops->send_request(dev, VHOST_USER_SET_VRING_KICK, &file);
70 
71 	return 0;
72 }
73 
74 static int
75 virtio_user_queue_setup(struct virtio_user_dev *dev,
76 			int (*fn)(struct virtio_user_dev *, uint32_t))
77 {
78 	uint32_t i, queue_sel;
79 
80 	for (i = 0; i < dev->max_queue_pairs; ++i) {
81 		queue_sel = 2 * i + VTNET_SQ_RQ_QUEUE_IDX;
82 		if (fn(dev, queue_sel) < 0) {
83 			PMD_DRV_LOG(INFO, "setup rx vq fails: %u", i);
84 			return -1;
85 		}
86 	}
87 	for (i = 0; i < dev->max_queue_pairs; ++i) {
88 		queue_sel = 2 * i + VTNET_SQ_TQ_QUEUE_IDX;
89 		if (fn(dev, queue_sel) < 0) {
90 			PMD_DRV_LOG(INFO, "setup tx vq fails: %u", i);
91 			return -1;
92 		}
93 	}
94 
95 	return 0;
96 }
97 
98 int
99 is_vhost_user_by_type(const char *path)
100 {
101 	struct stat sb;
102 
103 	if (stat(path, &sb) == -1)
104 		return 0;
105 
106 	return S_ISSOCK(sb.st_mode);
107 }
108 
109 int
110 virtio_user_start_device(struct virtio_user_dev *dev)
111 {
112 	uint64_t features;
113 	int ret;
114 
115 	pthread_mutex_lock(&dev->mutex);
116 
117 	if (is_vhost_user_by_type(dev->path) && dev->vhostfd < 0)
118 		goto error;
119 
120 	/* Do not check return as already done in init, or reset in stop */
121 	dev->ops->send_request(dev, VHOST_USER_SET_OWNER, NULL);
122 
123 	/* Step 0: tell vhost to create queues */
124 	if (virtio_user_queue_setup(dev, virtio_user_create_queue) < 0)
125 		goto error;
126 
127 	/* Step 1: set features */
128 	features = dev->features;
129 	/* Strip VIRTIO_NET_F_MAC, as MAC address is handled in vdev init */
130 	features &= ~(1ull << VIRTIO_NET_F_MAC);
131 	/* Strip VIRTIO_NET_F_CTRL_VQ, as devices do not really need to know */
132 	features &= ~(1ull << VIRTIO_NET_F_CTRL_VQ);
133 	features &= ~(1ull << VIRTIO_NET_F_STATUS);
134 	ret = dev->ops->send_request(dev, VHOST_USER_SET_FEATURES, &features);
135 	if (ret < 0)
136 		goto error;
137 	PMD_DRV_LOG(INFO, "set features: %" PRIx64, features);
138 
139 	/* Step 2: share memory regions */
140 	ret = dev->ops->send_request(dev, VHOST_USER_SET_MEM_TABLE, NULL);
141 	if (ret < 0)
142 		goto error;
143 
144 	/* Step 3: kick queues */
145 	if (virtio_user_queue_setup(dev, virtio_user_kick_queue) < 0)
146 		goto error;
147 
148 	/* Step 4: enable queues
149 	 * we enable the 1st queue pair by default.
150 	 */
151 	dev->ops->enable_qp(dev, 0, 1);
152 
153 	dev->started = true;
154 	pthread_mutex_unlock(&dev->mutex);
155 
156 	return 0;
157 error:
158 	pthread_mutex_unlock(&dev->mutex);
159 	/* TODO: free resource here or caller to check */
160 	return -1;
161 }
162 
163 int virtio_user_stop_device(struct virtio_user_dev *dev)
164 {
165 	uint32_t i;
166 
167 	pthread_mutex_lock(&dev->mutex);
168 	for (i = 0; i < dev->max_queue_pairs; ++i)
169 		dev->ops->enable_qp(dev, i, 0);
170 
171 	if (dev->ops->send_request(dev, VHOST_USER_RESET_OWNER, NULL) < 0) {
172 		PMD_DRV_LOG(INFO, "Failed to reset the device\n");
173 		pthread_mutex_unlock(&dev->mutex);
174 		return -1;
175 	}
176 	dev->started = false;
177 	pthread_mutex_unlock(&dev->mutex);
178 
179 	return 0;
180 }
181 
182 static inline void
183 parse_mac(struct virtio_user_dev *dev, const char *mac)
184 {
185 	int i, r;
186 	uint32_t tmp[ETHER_ADDR_LEN];
187 
188 	if (!mac)
189 		return;
190 
191 	r = sscanf(mac, "%x:%x:%x:%x:%x:%x", &tmp[0],
192 			&tmp[1], &tmp[2], &tmp[3], &tmp[4], &tmp[5]);
193 	if (r == ETHER_ADDR_LEN) {
194 		for (i = 0; i < ETHER_ADDR_LEN; ++i)
195 			dev->mac_addr[i] = (uint8_t)tmp[i];
196 		dev->mac_specified = 1;
197 	} else {
198 		/* ignore the wrong mac, use random mac */
199 		PMD_DRV_LOG(ERR, "wrong format of mac: %s", mac);
200 	}
201 }
202 
203 static int
204 virtio_user_dev_init_notify(struct virtio_user_dev *dev)
205 {
206 	uint32_t i, j;
207 	int callfd;
208 	int kickfd;
209 
210 	for (i = 0; i < VIRTIO_MAX_VIRTQUEUES; ++i) {
211 		if (i >= dev->max_queue_pairs * 2) {
212 			dev->kickfds[i] = -1;
213 			dev->callfds[i] = -1;
214 			continue;
215 		}
216 
217 		/* May use invalid flag, but some backend uses kickfd and
218 		 * callfd as criteria to judge if dev is alive. so finally we
219 		 * use real event_fd.
220 		 */
221 		callfd = eventfd(0, EFD_CLOEXEC | EFD_NONBLOCK);
222 		if (callfd < 0) {
223 			PMD_DRV_LOG(ERR, "callfd error, %s", strerror(errno));
224 			break;
225 		}
226 		kickfd = eventfd(0, EFD_CLOEXEC | EFD_NONBLOCK);
227 		if (kickfd < 0) {
228 			PMD_DRV_LOG(ERR, "kickfd error, %s", strerror(errno));
229 			break;
230 		}
231 		dev->callfds[i] = callfd;
232 		dev->kickfds[i] = kickfd;
233 	}
234 
235 	if (i < VIRTIO_MAX_VIRTQUEUES) {
236 		for (j = 0; j <= i; ++j) {
237 			close(dev->callfds[j]);
238 			close(dev->kickfds[j]);
239 		}
240 
241 		return -1;
242 	}
243 
244 	return 0;
245 }
246 
247 static int
248 virtio_user_fill_intr_handle(struct virtio_user_dev *dev)
249 {
250 	uint32_t i;
251 	struct rte_eth_dev *eth_dev = &rte_eth_devices[dev->port_id];
252 
253 	if (!eth_dev->intr_handle) {
254 		eth_dev->intr_handle = malloc(sizeof(*eth_dev->intr_handle));
255 		if (!eth_dev->intr_handle) {
256 			PMD_DRV_LOG(ERR, "fail to allocate intr_handle");
257 			return -1;
258 		}
259 		memset(eth_dev->intr_handle, 0, sizeof(*eth_dev->intr_handle));
260 	}
261 
262 	for (i = 0; i < dev->max_queue_pairs; ++i)
263 		eth_dev->intr_handle->efds[i] = dev->callfds[i];
264 	eth_dev->intr_handle->nb_efd = dev->max_queue_pairs;
265 	eth_dev->intr_handle->max_intr = dev->max_queue_pairs + 1;
266 	eth_dev->intr_handle->type = RTE_INTR_HANDLE_VDEV;
267 	/* For virtio vdev, no need to read counter for clean */
268 	eth_dev->intr_handle->efd_counter_size = 0;
269 	eth_dev->intr_handle->fd = -1;
270 	if (dev->vhostfd >= 0)
271 		eth_dev->intr_handle->fd = dev->vhostfd;
272 	else if (dev->is_server)
273 		eth_dev->intr_handle->fd = dev->listenfd;
274 
275 	return 0;
276 }
277 
278 static void
279 virtio_user_mem_event_cb(enum rte_mem_event type __rte_unused,
280 						 const void *addr __rte_unused,
281 						 size_t len __rte_unused,
282 						 void *arg)
283 {
284 	struct virtio_user_dev *dev = arg;
285 	uint16_t i;
286 
287 	pthread_mutex_lock(&dev->mutex);
288 
289 	if (dev->started == false)
290 		goto exit;
291 
292 	/* Step 1: pause the active queues */
293 	for (i = 0; i < dev->queue_pairs; i++)
294 		dev->ops->enable_qp(dev, i, 0);
295 
296 	/* Step 2: update memory regions */
297 	dev->ops->send_request(dev, VHOST_USER_SET_MEM_TABLE, NULL);
298 
299 	/* Step 3: resume the active queues */
300 	for (i = 0; i < dev->queue_pairs; i++)
301 		dev->ops->enable_qp(dev, i, 1);
302 
303 exit:
304 	pthread_mutex_unlock(&dev->mutex);
305 }
306 
307 static int
308 virtio_user_dev_setup(struct virtio_user_dev *dev)
309 {
310 	uint32_t q;
311 
312 	dev->vhostfd = -1;
313 	dev->vhostfds = NULL;
314 	dev->tapfds = NULL;
315 
316 	if (dev->is_server) {
317 		if (access(dev->path, F_OK) == 0 &&
318 		    !is_vhost_user_by_type(dev->path)) {
319 			PMD_DRV_LOG(ERR, "Server mode doesn't support vhost-kernel!");
320 			return -1;
321 		}
322 		dev->ops = &ops_user;
323 	} else {
324 		if (is_vhost_user_by_type(dev->path)) {
325 			dev->ops = &ops_user;
326 		} else {
327 			dev->ops = &ops_kernel;
328 
329 			dev->vhostfds = malloc(dev->max_queue_pairs *
330 					       sizeof(int));
331 			dev->tapfds = malloc(dev->max_queue_pairs *
332 					     sizeof(int));
333 			if (!dev->vhostfds || !dev->tapfds) {
334 				PMD_INIT_LOG(ERR, "Failed to malloc");
335 				return -1;
336 			}
337 
338 			for (q = 0; q < dev->max_queue_pairs; ++q) {
339 				dev->vhostfds[q] = -1;
340 				dev->tapfds[q] = -1;
341 			}
342 		}
343 	}
344 
345 	if (dev->ops->setup(dev) < 0)
346 		return -1;
347 
348 	if (virtio_user_dev_init_notify(dev) < 0)
349 		return -1;
350 
351 	if (virtio_user_fill_intr_handle(dev) < 0)
352 		return -1;
353 
354 	return 0;
355 }
356 
357 /* Use below macro to filter features from vhost backend */
358 #define VIRTIO_USER_SUPPORTED_FEATURES			\
359 	(1ULL << VIRTIO_NET_F_MAC		|	\
360 	 1ULL << VIRTIO_NET_F_STATUS		|	\
361 	 1ULL << VIRTIO_NET_F_MQ		|	\
362 	 1ULL << VIRTIO_NET_F_CTRL_MAC_ADDR	|	\
363 	 1ULL << VIRTIO_NET_F_CTRL_VQ		|	\
364 	 1ULL << VIRTIO_NET_F_CTRL_RX		|	\
365 	 1ULL << VIRTIO_NET_F_CTRL_VLAN		|	\
366 	 1ULL << VIRTIO_NET_F_CSUM		|	\
367 	 1ULL << VIRTIO_NET_F_HOST_TSO4		|	\
368 	 1ULL << VIRTIO_NET_F_HOST_TSO6		|	\
369 	 1ULL << VIRTIO_NET_F_MRG_RXBUF		|	\
370 	 1ULL << VIRTIO_RING_F_INDIRECT_DESC	|	\
371 	 1ULL << VIRTIO_NET_F_GUEST_CSUM	|	\
372 	 1ULL << VIRTIO_NET_F_GUEST_TSO4	|	\
373 	 1ULL << VIRTIO_NET_F_GUEST_TSO6	|	\
374 	 1ULL << VIRTIO_F_VERSION_1)
375 
376 int
377 virtio_user_dev_init(struct virtio_user_dev *dev, char *path, int queues,
378 		     int cq, int queue_size, const char *mac, char **ifname)
379 {
380 	pthread_mutex_init(&dev->mutex, NULL);
381 	snprintf(dev->path, PATH_MAX, "%s", path);
382 	dev->started = 0;
383 	dev->max_queue_pairs = queues;
384 	dev->queue_pairs = 1; /* mq disabled by default */
385 	dev->queue_size = queue_size;
386 	dev->mac_specified = 0;
387 	parse_mac(dev, mac);
388 
389 	if (*ifname) {
390 		dev->ifname = *ifname;
391 		*ifname = NULL;
392 	}
393 
394 	if (virtio_user_dev_setup(dev) < 0) {
395 		PMD_INIT_LOG(ERR, "backend set up fails");
396 		return -1;
397 	}
398 
399 	if (!dev->is_server) {
400 		if (dev->ops->send_request(dev, VHOST_USER_SET_OWNER,
401 					   NULL) < 0) {
402 			PMD_INIT_LOG(ERR, "set_owner fails: %s",
403 				     strerror(errno));
404 			return -1;
405 		}
406 
407 		if (dev->ops->send_request(dev, VHOST_USER_GET_FEATURES,
408 					   &dev->device_features) < 0) {
409 			PMD_INIT_LOG(ERR, "get_features failed: %s",
410 				     strerror(errno));
411 			return -1;
412 		}
413 	} else {
414 		/* We just pretend vhost-user can support all these features.
415 		 * Note that this could be problematic that if some feature is
416 		 * negotiated but not supported by the vhost-user which comes
417 		 * later.
418 		 */
419 		dev->device_features = VIRTIO_USER_SUPPORTED_FEATURES;
420 	}
421 
422 	if (dev->mac_specified)
423 		dev->device_features |= (1ull << VIRTIO_NET_F_MAC);
424 	else
425 		dev->device_features &= ~(1ull << VIRTIO_NET_F_MAC);
426 
427 	if (cq) {
428 		/* device does not really need to know anything about CQ,
429 		 * so if necessary, we just claim to support CQ
430 		 */
431 		dev->device_features |= (1ull << VIRTIO_NET_F_CTRL_VQ);
432 	} else {
433 		dev->device_features &= ~(1ull << VIRTIO_NET_F_CTRL_VQ);
434 		/* Also disable features depends on VIRTIO_NET_F_CTRL_VQ */
435 		dev->device_features &= ~(1ull << VIRTIO_NET_F_CTRL_RX);
436 		dev->device_features &= ~(1ull << VIRTIO_NET_F_CTRL_VLAN);
437 		dev->device_features &= ~(1ull << VIRTIO_NET_F_GUEST_ANNOUNCE);
438 		dev->device_features &= ~(1ull << VIRTIO_NET_F_MQ);
439 		dev->device_features &= ~(1ull << VIRTIO_NET_F_CTRL_MAC_ADDR);
440 	}
441 
442 	/* The backend will not report this feature, we add it explicitly */
443 	if (is_vhost_user_by_type(dev->path))
444 		dev->device_features |= (1ull << VIRTIO_NET_F_STATUS);
445 
446 	dev->device_features &= VIRTIO_USER_SUPPORTED_FEATURES;
447 
448 	if (rte_mem_event_callback_register(VIRTIO_USER_MEM_EVENT_CLB_NAME,
449 				virtio_user_mem_event_cb, dev)) {
450 		if (rte_errno != ENOTSUP) {
451 			PMD_INIT_LOG(ERR, "Failed to register mem event"
452 					" callback\n");
453 			return -1;
454 		}
455 	}
456 
457 	return 0;
458 }
459 
460 void
461 virtio_user_dev_uninit(struct virtio_user_dev *dev)
462 {
463 	uint32_t i;
464 
465 	virtio_user_stop_device(dev);
466 
467 	rte_mem_event_callback_unregister(VIRTIO_USER_MEM_EVENT_CLB_NAME, dev);
468 
469 	for (i = 0; i < dev->max_queue_pairs * 2; ++i) {
470 		close(dev->callfds[i]);
471 		close(dev->kickfds[i]);
472 	}
473 
474 	close(dev->vhostfd);
475 
476 	if (dev->is_server && dev->listenfd >= 0) {
477 		close(dev->listenfd);
478 		dev->listenfd = -1;
479 	}
480 
481 	if (dev->vhostfds) {
482 		for (i = 0; i < dev->max_queue_pairs; ++i)
483 			close(dev->vhostfds[i]);
484 		free(dev->vhostfds);
485 		free(dev->tapfds);
486 	}
487 
488 	free(dev->ifname);
489 
490 	if (dev->is_server)
491 		unlink(dev->path);
492 }
493 
494 uint8_t
495 virtio_user_handle_mq(struct virtio_user_dev *dev, uint16_t q_pairs)
496 {
497 	uint16_t i;
498 	uint8_t ret = 0;
499 
500 	if (q_pairs > dev->max_queue_pairs) {
501 		PMD_INIT_LOG(ERR, "multi-q config %u, but only %u supported",
502 			     q_pairs, dev->max_queue_pairs);
503 		return -1;
504 	}
505 
506 	/* Server mode can't enable queue pairs if vhostfd is invalid,
507 	 * always return 0 in this case.
508 	 */
509 	if (dev->vhostfd >= 0) {
510 		for (i = 0; i < q_pairs; ++i)
511 			ret |= dev->ops->enable_qp(dev, i, 1);
512 		for (i = q_pairs; i < dev->max_queue_pairs; ++i)
513 			ret |= dev->ops->enable_qp(dev, i, 0);
514 	} else if (!dev->is_server) {
515 		ret = ~0;
516 	}
517 	dev->queue_pairs = q_pairs;
518 
519 	return ret;
520 }
521 
522 static uint32_t
523 virtio_user_handle_ctrl_msg(struct virtio_user_dev *dev, struct vring *vring,
524 			    uint16_t idx_hdr)
525 {
526 	struct virtio_net_ctrl_hdr *hdr;
527 	virtio_net_ctrl_ack status = ~0;
528 	uint16_t i, idx_data, idx_status;
529 	uint32_t n_descs = 0;
530 
531 	/* locate desc for header, data, and status */
532 	idx_data = vring->desc[idx_hdr].next;
533 	n_descs++;
534 
535 	i = idx_data;
536 	while (vring->desc[i].flags == VRING_DESC_F_NEXT) {
537 		i = vring->desc[i].next;
538 		n_descs++;
539 	}
540 
541 	/* locate desc for status */
542 	idx_status = i;
543 	n_descs++;
544 
545 	hdr = (void *)(uintptr_t)vring->desc[idx_hdr].addr;
546 	if (hdr->class == VIRTIO_NET_CTRL_MQ &&
547 	    hdr->cmd == VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET) {
548 		uint16_t queues;
549 
550 		queues = *(uint16_t *)(uintptr_t)vring->desc[idx_data].addr;
551 		status = virtio_user_handle_mq(dev, queues);
552 	}
553 
554 	/* Update status */
555 	*(virtio_net_ctrl_ack *)(uintptr_t)vring->desc[idx_status].addr = status;
556 
557 	return n_descs;
558 }
559 
560 void
561 virtio_user_handle_cq(struct virtio_user_dev *dev, uint16_t queue_idx)
562 {
563 	uint16_t avail_idx, desc_idx;
564 	struct vring_used_elem *uep;
565 	uint32_t n_descs;
566 	struct vring *vring = &dev->vrings[queue_idx];
567 
568 	/* Consume avail ring, using used ring idx as first one */
569 	while (vring->used->idx != vring->avail->idx) {
570 		avail_idx = (vring->used->idx) & (vring->num - 1);
571 		desc_idx = vring->avail->ring[avail_idx];
572 
573 		n_descs = virtio_user_handle_ctrl_msg(dev, vring, desc_idx);
574 
575 		/* Update used ring */
576 		uep = &vring->used->ring[avail_idx];
577 		uep->id = avail_idx;
578 		uep->len = n_descs;
579 
580 		vring->used->idx++;
581 	}
582 }
583