xref: /dpdk/drivers/net/virtio/virtio_user/virtio_user_dev.c (revision 6b72aad61f09b870427f4ebcedae525a985bb37a)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright(c) 2010-2016 Intel Corporation. All rights reserved.
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  *
11  *     * Redistributions of source code must retain the above copyright
12  *       notice, this list of conditions and the following disclaimer.
13  *     * Redistributions in binary form must reproduce the above copyright
14  *       notice, this list of conditions and the following disclaimer in
15  *       the documentation and/or other materials provided with the
16  *       distribution.
17  *     * Neither the name of Intel Corporation nor the names of its
18  *       contributors may be used to endorse or promote products derived
19  *       from this software without specific prior written permission.
20  *
21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <stdint.h>
35 #include <stdio.h>
36 #include <fcntl.h>
37 #include <string.h>
38 #include <errno.h>
39 #include <sys/mman.h>
40 #include <unistd.h>
41 #include <sys/eventfd.h>
42 #include <sys/types.h>
43 #include <sys/stat.h>
44 #include <unistd.h>
45 
46 #include "vhost.h"
47 #include "virtio_user_dev.h"
48 #include "../virtio_ethdev.h"
49 
50 static int
51 virtio_user_create_queue(struct virtio_user_dev *dev, uint32_t queue_sel)
52 {
53 	/* Of all per virtqueue MSGs, make sure VHOST_SET_VRING_CALL come
54 	 * firstly because vhost depends on this msg to allocate virtqueue
55 	 * pair.
56 	 */
57 	int callfd;
58 	struct vhost_vring_file file;
59 
60 	/* May use invalid flag, but some backend leverages kickfd and callfd as
61 	 * criteria to judge if dev is alive. so finally we use real event_fd.
62 	 */
63 	callfd = eventfd(0, EFD_CLOEXEC | EFD_NONBLOCK);
64 	if (callfd < 0) {
65 		PMD_DRV_LOG(ERR, "callfd error, %s", strerror(errno));
66 		return -1;
67 	}
68 	file.index = queue_sel;
69 	file.fd = callfd;
70 	dev->ops->send_request(dev, VHOST_USER_SET_VRING_CALL, &file);
71 	dev->callfds[queue_sel] = callfd;
72 
73 	return 0;
74 }
75 
76 static int
77 virtio_user_kick_queue(struct virtio_user_dev *dev, uint32_t queue_sel)
78 {
79 	int kickfd;
80 	struct vhost_vring_file file;
81 	struct vhost_vring_state state;
82 	struct vring *vring = &dev->vrings[queue_sel];
83 	struct vhost_vring_addr addr = {
84 		.index = queue_sel,
85 		.desc_user_addr = (uint64_t)(uintptr_t)vring->desc,
86 		.avail_user_addr = (uint64_t)(uintptr_t)vring->avail,
87 		.used_user_addr = (uint64_t)(uintptr_t)vring->used,
88 		.log_guest_addr = 0,
89 		.flags = 0, /* disable log */
90 	};
91 
92 	state.index = queue_sel;
93 	state.num = vring->num;
94 	dev->ops->send_request(dev, VHOST_USER_SET_VRING_NUM, &state);
95 
96 	state.index = queue_sel;
97 	state.num = 0; /* no reservation */
98 	dev->ops->send_request(dev, VHOST_USER_SET_VRING_BASE, &state);
99 
100 	dev->ops->send_request(dev, VHOST_USER_SET_VRING_ADDR, &addr);
101 
102 	/* Of all per virtqueue MSGs, make sure VHOST_USER_SET_VRING_KICK comes
103 	 * lastly because vhost depends on this msg to judge if
104 	 * virtio is ready.
105 	 */
106 	kickfd = eventfd(0, EFD_CLOEXEC | EFD_NONBLOCK);
107 	if (kickfd < 0) {
108 		PMD_DRV_LOG(ERR, "kickfd error, %s", strerror(errno));
109 		return -1;
110 	}
111 	file.index = queue_sel;
112 	file.fd = kickfd;
113 	dev->ops->send_request(dev, VHOST_USER_SET_VRING_KICK, &file);
114 	dev->kickfds[queue_sel] = kickfd;
115 
116 	return 0;
117 }
118 
119 static int
120 virtio_user_queue_setup(struct virtio_user_dev *dev,
121 			int (*fn)(struct virtio_user_dev *, uint32_t))
122 {
123 	uint32_t i, queue_sel;
124 
125 	for (i = 0; i < dev->max_queue_pairs; ++i) {
126 		queue_sel = 2 * i + VTNET_SQ_RQ_QUEUE_IDX;
127 		if (fn(dev, queue_sel) < 0) {
128 			PMD_DRV_LOG(INFO, "setup rx vq fails: %u", i);
129 			return -1;
130 		}
131 	}
132 	for (i = 0; i < dev->max_queue_pairs; ++i) {
133 		queue_sel = 2 * i + VTNET_SQ_TQ_QUEUE_IDX;
134 		if (fn(dev, queue_sel) < 0) {
135 			PMD_DRV_LOG(INFO, "setup tx vq fails: %u", i);
136 			return -1;
137 		}
138 	}
139 
140 	return 0;
141 }
142 
143 int
144 virtio_user_start_device(struct virtio_user_dev *dev)
145 {
146 	uint64_t features;
147 	int ret;
148 
149 	/* Step 0: tell vhost to create queues */
150 	if (virtio_user_queue_setup(dev, virtio_user_create_queue) < 0)
151 		goto error;
152 
153 	/* Step 1: set features */
154 	features = dev->features;
155 	/* Strip VIRTIO_NET_F_MAC, as MAC address is handled in vdev init */
156 	features &= ~(1ull << VIRTIO_NET_F_MAC);
157 	/* Strip VIRTIO_NET_F_CTRL_VQ, as devices do not really need to know */
158 	features &= ~(1ull << VIRTIO_NET_F_CTRL_VQ);
159 	ret = dev->ops->send_request(dev, VHOST_USER_SET_FEATURES, &features);
160 	if (ret < 0)
161 		goto error;
162 	PMD_DRV_LOG(INFO, "set features: %" PRIx64, features);
163 
164 	/* Step 2: share memory regions */
165 	ret = dev->ops->send_request(dev, VHOST_USER_SET_MEM_TABLE, NULL);
166 	if (ret < 0)
167 		goto error;
168 
169 	/* Step 3: kick queues */
170 	if (virtio_user_queue_setup(dev, virtio_user_kick_queue) < 0)
171 		goto error;
172 
173 	/* Step 4: enable queues
174 	 * we enable the 1st queue pair by default.
175 	 */
176 	dev->ops->enable_qp(dev, 0, 1);
177 
178 	return 0;
179 error:
180 	/* TODO: free resource here or caller to check */
181 	return -1;
182 }
183 
184 int virtio_user_stop_device(struct virtio_user_dev *dev)
185 {
186 	uint32_t i;
187 
188 	for (i = 0; i < dev->max_queue_pairs * 2; ++i) {
189 		close(dev->callfds[i]);
190 		close(dev->kickfds[i]);
191 	}
192 
193 	for (i = 0; i < dev->max_queue_pairs; ++i)
194 		dev->ops->enable_qp(dev, i, 0);
195 
196 	free(dev->ifname);
197 	dev->ifname = NULL;
198 
199 	return 0;
200 }
201 
202 static inline void
203 parse_mac(struct virtio_user_dev *dev, const char *mac)
204 {
205 	int i, r;
206 	uint32_t tmp[ETHER_ADDR_LEN];
207 
208 	if (!mac)
209 		return;
210 
211 	r = sscanf(mac, "%x:%x:%x:%x:%x:%x", &tmp[0],
212 			&tmp[1], &tmp[2], &tmp[3], &tmp[4], &tmp[5]);
213 	if (r == ETHER_ADDR_LEN) {
214 		for (i = 0; i < ETHER_ADDR_LEN; ++i)
215 			dev->mac_addr[i] = (uint8_t)tmp[i];
216 		dev->mac_specified = 1;
217 	} else {
218 		/* ignore the wrong mac, use random mac */
219 		PMD_DRV_LOG(ERR, "wrong format of mac: %s", mac);
220 	}
221 }
222 
223 static int
224 is_vhost_user_by_type(const char *path)
225 {
226 	struct stat sb;
227 
228 	if (stat(path, &sb) == -1)
229 		return 0;
230 
231 	return S_ISSOCK(sb.st_mode);
232 }
233 
234 static int
235 virtio_user_dev_setup(struct virtio_user_dev *dev)
236 {
237 	uint32_t i, q;
238 
239 	dev->vhostfd = -1;
240 	for (i = 0; i < VIRTIO_MAX_VIRTQUEUES * 2 + 1; ++i) {
241 		dev->kickfds[i] = -1;
242 		dev->callfds[i] = -1;
243 	}
244 
245 	dev->vhostfds = NULL;
246 	dev->tapfds = NULL;
247 
248 	if (is_vhost_user_by_type(dev->path)) {
249 		dev->ops = &ops_user;
250 	} else {
251 		dev->ops = &ops_kernel;
252 
253 		dev->vhostfds = malloc(dev->max_queue_pairs * sizeof(int));
254 		dev->tapfds = malloc(dev->max_queue_pairs * sizeof(int));
255 		if (!dev->vhostfds || !dev->tapfds) {
256 			PMD_INIT_LOG(ERR, "Failed to malloc");
257 			return -1;
258 		}
259 
260 		for (q = 0; q < dev->max_queue_pairs; ++q) {
261 			dev->vhostfds[q] = -1;
262 			dev->tapfds[q] = -1;
263 		}
264 	}
265 
266 	return dev->ops->setup(dev);
267 }
268 
269 int
270 virtio_user_dev_init(struct virtio_user_dev *dev, char *path, int queues,
271 		     int cq, int queue_size, const char *mac)
272 {
273 	snprintf(dev->path, PATH_MAX, "%s", path);
274 	dev->max_queue_pairs = queues;
275 	dev->queue_pairs = 1; /* mq disabled by default */
276 	dev->queue_size = queue_size;
277 	dev->mac_specified = 0;
278 	parse_mac(dev, mac);
279 
280 	if (virtio_user_dev_setup(dev) < 0) {
281 		PMD_INIT_LOG(ERR, "backend set up fails");
282 		return -1;
283 	}
284 	if (dev->ops->send_request(dev, VHOST_USER_SET_OWNER, NULL) < 0) {
285 		PMD_INIT_LOG(ERR, "set_owner fails: %s", strerror(errno));
286 		return -1;
287 	}
288 
289 	if (dev->ops->send_request(dev, VHOST_USER_GET_FEATURES,
290 			    &dev->device_features) < 0) {
291 		PMD_INIT_LOG(ERR, "get_features failed: %s", strerror(errno));
292 		return -1;
293 	}
294 	if (dev->mac_specified)
295 		dev->device_features |= (1ull << VIRTIO_NET_F_MAC);
296 
297 	if (cq) {
298 		/* device does not really need to know anything about CQ,
299 		 * so if necessary, we just claim to support CQ
300 		 */
301 		dev->device_features |= (1ull << VIRTIO_NET_F_CTRL_VQ);
302 	} else {
303 		dev->device_features &= ~(1ull << VIRTIO_NET_F_CTRL_VQ);
304 		/* Also disable features depends on VIRTIO_NET_F_CTRL_VQ */
305 		dev->device_features &= ~(1ull << VIRTIO_NET_F_CTRL_RX);
306 		dev->device_features &= ~(1ull << VIRTIO_NET_F_CTRL_VLAN);
307 		dev->device_features &= ~(1ull << VIRTIO_NET_F_GUEST_ANNOUNCE);
308 		dev->device_features &= ~(1ull << VIRTIO_NET_F_MQ);
309 		dev->device_features &= ~(1ull << VIRTIO_NET_F_CTRL_MAC_ADDR);
310 	}
311 
312 	return 0;
313 }
314 
315 void
316 virtio_user_dev_uninit(struct virtio_user_dev *dev)
317 {
318 	uint32_t i;
319 
320 	virtio_user_stop_device(dev);
321 
322 	close(dev->vhostfd);
323 
324 	if (dev->vhostfds) {
325 		for (i = 0; i < dev->max_queue_pairs; ++i)
326 			close(dev->vhostfds[i]);
327 		free(dev->vhostfds);
328 		free(dev->tapfds);
329 	}
330 }
331 
332 static uint8_t
333 virtio_user_handle_mq(struct virtio_user_dev *dev, uint16_t q_pairs)
334 {
335 	uint16_t i;
336 	uint8_t ret = 0;
337 
338 	if (q_pairs > dev->max_queue_pairs) {
339 		PMD_INIT_LOG(ERR, "multi-q config %u, but only %u supported",
340 			     q_pairs, dev->max_queue_pairs);
341 		return -1;
342 	}
343 
344 	for (i = 0; i < q_pairs; ++i)
345 		ret |= dev->ops->enable_qp(dev, i, 1);
346 	for (i = q_pairs; i < dev->max_queue_pairs; ++i)
347 		ret |= dev->ops->enable_qp(dev, i, 0);
348 
349 	dev->queue_pairs = q_pairs;
350 
351 	return ret;
352 }
353 
354 static uint32_t
355 virtio_user_handle_ctrl_msg(struct virtio_user_dev *dev, struct vring *vring,
356 			    uint16_t idx_hdr)
357 {
358 	struct virtio_net_ctrl_hdr *hdr;
359 	virtio_net_ctrl_ack status = ~0;
360 	uint16_t i, idx_data, idx_status;
361 	uint32_t n_descs = 0;
362 
363 	/* locate desc for header, data, and status */
364 	idx_data = vring->desc[idx_hdr].next;
365 	n_descs++;
366 
367 	i = idx_data;
368 	while (vring->desc[i].flags == VRING_DESC_F_NEXT) {
369 		i = vring->desc[i].next;
370 		n_descs++;
371 	}
372 
373 	/* locate desc for status */
374 	idx_status = i;
375 	n_descs++;
376 
377 	hdr = (void *)(uintptr_t)vring->desc[idx_hdr].addr;
378 	if (hdr->class == VIRTIO_NET_CTRL_MQ &&
379 	    hdr->cmd == VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET) {
380 		uint16_t queues;
381 
382 		queues = *(uint16_t *)(uintptr_t)vring->desc[idx_data].addr;
383 		status = virtio_user_handle_mq(dev, queues);
384 	}
385 
386 	/* Update status */
387 	*(virtio_net_ctrl_ack *)(uintptr_t)vring->desc[idx_status].addr = status;
388 
389 	return n_descs;
390 }
391 
392 void
393 virtio_user_handle_cq(struct virtio_user_dev *dev, uint16_t queue_idx)
394 {
395 	uint16_t avail_idx, desc_idx;
396 	struct vring_used_elem *uep;
397 	uint32_t n_descs;
398 	struct vring *vring = &dev->vrings[queue_idx];
399 
400 	/* Consume avail ring, using used ring idx as first one */
401 	while (vring->used->idx != vring->avail->idx) {
402 		avail_idx = (vring->used->idx) & (vring->num - 1);
403 		desc_idx = vring->avail->ring[avail_idx];
404 
405 		n_descs = virtio_user_handle_ctrl_msg(dev, vring, desc_idx);
406 
407 		/* Update used ring */
408 		uep = &vring->used->ring[avail_idx];
409 		uep->id = avail_idx;
410 		uep->len = n_descs;
411 
412 		vring->used->idx++;
413 	}
414 }
415