1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2010-2016 Intel Corporation
3 */
4
5 #include <sys/socket.h>
6 #include <sys/types.h>
7 #include <sys/stat.h>
8 #include <unistd.h>
9 #include <fcntl.h>
10 #include <sys/un.h>
11 #include <string.h>
12 #include <errno.h>
13
14 #include <rte_string_fns.h>
15 #include <rte_fbarray.h>
16
17 #include "vhost.h"
18 #include "virtio_user_dev.h"
19
20 /* The version of the protocol we support */
21 #define VHOST_USER_VERSION 0x1
22
23 #define VHOST_MEMORY_MAX_NREGIONS 8
24 struct vhost_memory {
25 uint32_t nregions;
26 uint32_t padding;
27 struct vhost_memory_region regions[VHOST_MEMORY_MAX_NREGIONS];
28 };
29
30 struct vhost_user_msg {
31 enum vhost_user_request request;
32
33 #define VHOST_USER_VERSION_MASK 0x3
34 #define VHOST_USER_REPLY_MASK (0x1 << 2)
35 #define VHOST_USER_NEED_REPLY_MASK (0x1 << 3)
36 uint32_t flags;
37 uint32_t size; /* the following payload size */
38 union {
39 #define VHOST_USER_VRING_IDX_MASK 0xff
40 #define VHOST_USER_VRING_NOFD_MASK (0x1 << 8)
41 uint64_t u64;
42 struct vhost_vring_state state;
43 struct vhost_vring_addr addr;
44 struct vhost_memory memory;
45 } payload;
46 int fds[VHOST_MEMORY_MAX_NREGIONS];
47 } __rte_packed;
48
49 #define VHOST_USER_HDR_SIZE offsetof(struct vhost_user_msg, payload.u64)
50 #define VHOST_USER_PAYLOAD_SIZE \
51 (sizeof(struct vhost_user_msg) - VHOST_USER_HDR_SIZE)
52
53 static int
vhost_user_write(int fd,void * buf,int len,int * fds,int fd_num)54 vhost_user_write(int fd, void *buf, int len, int *fds, int fd_num)
55 {
56 int r;
57 struct msghdr msgh;
58 struct iovec iov;
59 size_t fd_size = fd_num * sizeof(int);
60 char control[CMSG_SPACE(fd_size)];
61 struct cmsghdr *cmsg;
62
63 memset(&msgh, 0, sizeof(msgh));
64 memset(control, 0, sizeof(control));
65
66 iov.iov_base = (uint8_t *)buf;
67 iov.iov_len = len;
68
69 msgh.msg_iov = &iov;
70 msgh.msg_iovlen = 1;
71 msgh.msg_control = control;
72 msgh.msg_controllen = sizeof(control);
73
74 cmsg = CMSG_FIRSTHDR(&msgh);
75 cmsg->cmsg_len = CMSG_LEN(fd_size);
76 cmsg->cmsg_level = SOL_SOCKET;
77 cmsg->cmsg_type = SCM_RIGHTS;
78 memcpy(CMSG_DATA(cmsg), fds, fd_size);
79
80 do {
81 r = sendmsg(fd, &msgh, 0);
82 } while (r < 0 && errno == EINTR);
83
84 return r;
85 }
86
87 static int
vhost_user_read(int fd,struct vhost_user_msg * msg)88 vhost_user_read(int fd, struct vhost_user_msg *msg)
89 {
90 uint32_t valid_flags = VHOST_USER_REPLY_MASK | VHOST_USER_VERSION;
91 int ret, sz_hdr = VHOST_USER_HDR_SIZE, sz_payload;
92
93 ret = recv(fd, (void *)msg, sz_hdr, 0);
94 if (ret < sz_hdr) {
95 PMD_DRV_LOG(ERR, "Failed to recv msg hdr: %d instead of %d.",
96 ret, sz_hdr);
97 goto fail;
98 }
99
100 /* validate msg flags */
101 if (msg->flags != (valid_flags)) {
102 PMD_DRV_LOG(ERR, "Failed to recv msg: flags %x instead of %x.",
103 msg->flags, valid_flags);
104 goto fail;
105 }
106
107 sz_payload = msg->size;
108
109 if ((size_t)sz_payload > sizeof(msg->payload))
110 goto fail;
111
112 if (sz_payload) {
113 ret = recv(fd, (void *)((char *)msg + sz_hdr), sz_payload, 0);
114 if (ret < sz_payload) {
115 PMD_DRV_LOG(ERR,
116 "Failed to recv msg payload: %d instead of %d.",
117 ret, msg->size);
118 goto fail;
119 }
120 }
121
122 return 0;
123
124 fail:
125 return -1;
126 }
127
128 struct walk_arg {
129 struct vhost_memory *vm;
130 int *fds;
131 int region_nr;
132 };
133
134 static int
update_memory_region(const struct rte_memseg_list * msl __rte_unused,const struct rte_memseg * ms,void * arg)135 update_memory_region(const struct rte_memseg_list *msl __rte_unused,
136 const struct rte_memseg *ms, void *arg)
137 {
138 struct walk_arg *wa = arg;
139 struct vhost_memory_region *mr;
140 uint64_t start_addr, end_addr;
141 size_t offset;
142 int i, fd;
143
144 fd = rte_memseg_get_fd_thread_unsafe(ms);
145 if (fd < 0) {
146 PMD_DRV_LOG(ERR, "Failed to get fd, ms=%p rte_errno=%d",
147 ms, rte_errno);
148 return -1;
149 }
150
151 if (rte_memseg_get_fd_offset_thread_unsafe(ms, &offset) < 0) {
152 PMD_DRV_LOG(ERR, "Failed to get offset, ms=%p rte_errno=%d",
153 ms, rte_errno);
154 return -1;
155 }
156
157 start_addr = (uint64_t)(uintptr_t)ms->addr;
158 end_addr = start_addr + ms->len;
159
160 for (i = 0; i < wa->region_nr; i++) {
161 if (wa->fds[i] != fd)
162 continue;
163
164 mr = &wa->vm->regions[i];
165
166 if (mr->userspace_addr + mr->memory_size < end_addr)
167 mr->memory_size = end_addr - mr->userspace_addr;
168
169 if (mr->userspace_addr > start_addr) {
170 mr->userspace_addr = start_addr;
171 mr->guest_phys_addr = start_addr;
172 }
173
174 if (mr->mmap_offset > offset)
175 mr->mmap_offset = offset;
176
177 PMD_DRV_LOG(DEBUG, "index=%d fd=%d offset=0x%" PRIx64
178 " addr=0x%" PRIx64 " len=%" PRIu64, i, fd,
179 mr->mmap_offset, mr->userspace_addr,
180 mr->memory_size);
181
182 return 0;
183 }
184
185 if (i >= VHOST_MEMORY_MAX_NREGIONS) {
186 PMD_DRV_LOG(ERR, "Too many memory regions");
187 return -1;
188 }
189
190 mr = &wa->vm->regions[i];
191 wa->fds[i] = fd;
192
193 mr->guest_phys_addr = start_addr;
194 mr->userspace_addr = start_addr;
195 mr->memory_size = ms->len;
196 mr->mmap_offset = offset;
197
198 PMD_DRV_LOG(DEBUG, "index=%d fd=%d offset=0x%" PRIx64
199 " addr=0x%" PRIx64 " len=%" PRIu64, i, fd,
200 mr->mmap_offset, mr->userspace_addr,
201 mr->memory_size);
202
203 wa->region_nr++;
204
205 return 0;
206 }
207
208 static int
prepare_vhost_memory_user(struct vhost_user_msg * msg,int fds[])209 prepare_vhost_memory_user(struct vhost_user_msg *msg, int fds[])
210 {
211 struct walk_arg wa;
212
213 wa.region_nr = 0;
214 wa.vm = &msg->payload.memory;
215 wa.fds = fds;
216
217 /*
218 * The memory lock has already been taken by memory subsystem
219 * or virtio_user_start_device().
220 */
221 if (rte_memseg_walk_thread_unsafe(update_memory_region, &wa) < 0)
222 return -1;
223
224 msg->payload.memory.nregions = wa.region_nr;
225 msg->payload.memory.padding = 0;
226
227 return 0;
228 }
229
230 static struct vhost_user_msg m;
231
232 const char * const vhost_msg_strings[] = {
233 [VHOST_USER_SET_OWNER] = "VHOST_SET_OWNER",
234 [VHOST_USER_RESET_OWNER] = "VHOST_RESET_OWNER",
235 [VHOST_USER_SET_FEATURES] = "VHOST_SET_FEATURES",
236 [VHOST_USER_GET_FEATURES] = "VHOST_GET_FEATURES",
237 [VHOST_USER_SET_VRING_CALL] = "VHOST_SET_VRING_CALL",
238 [VHOST_USER_SET_VRING_NUM] = "VHOST_SET_VRING_NUM",
239 [VHOST_USER_SET_VRING_BASE] = "VHOST_SET_VRING_BASE",
240 [VHOST_USER_GET_VRING_BASE] = "VHOST_GET_VRING_BASE",
241 [VHOST_USER_SET_VRING_ADDR] = "VHOST_SET_VRING_ADDR",
242 [VHOST_USER_SET_VRING_KICK] = "VHOST_SET_VRING_KICK",
243 [VHOST_USER_SET_MEM_TABLE] = "VHOST_SET_MEM_TABLE",
244 [VHOST_USER_SET_VRING_ENABLE] = "VHOST_SET_VRING_ENABLE",
245 [VHOST_USER_GET_PROTOCOL_FEATURES] = "VHOST_USER_GET_PROTOCOL_FEATURES",
246 [VHOST_USER_SET_PROTOCOL_FEATURES] = "VHOST_USER_SET_PROTOCOL_FEATURES",
247 [VHOST_USER_SET_STATUS] = "VHOST_SET_STATUS",
248 [VHOST_USER_GET_STATUS] = "VHOST_GET_STATUS",
249 };
250
251 static int
vhost_user_sock(struct virtio_user_dev * dev,enum vhost_user_request req,void * arg)252 vhost_user_sock(struct virtio_user_dev *dev,
253 enum vhost_user_request req,
254 void *arg)
255 {
256 struct vhost_user_msg msg;
257 struct vhost_vring_file *file = 0;
258 int need_reply = 0;
259 int has_reply_ack = 0;
260 int fds[VHOST_MEMORY_MAX_NREGIONS];
261 int fd_num = 0;
262 int len;
263 int vhostfd = dev->vhostfd;
264
265 RTE_SET_USED(m);
266
267 PMD_DRV_LOG(INFO, "%s", vhost_msg_strings[req]);
268
269 if (dev->is_server && vhostfd < 0)
270 return -1;
271
272 if (dev->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_REPLY_ACK))
273 has_reply_ack = 1;
274
275 msg.request = req;
276 msg.flags = VHOST_USER_VERSION;
277 msg.size = 0;
278
279 switch (req) {
280 case VHOST_USER_GET_STATUS:
281 if (!(dev->status & VIRTIO_CONFIG_STATUS_FEATURES_OK) ||
282 (!(dev->protocol_features &
283 (1ULL << VHOST_USER_PROTOCOL_F_STATUS))))
284 return -ENOTSUP;
285 /* Fallthrough */
286 case VHOST_USER_GET_FEATURES:
287 case VHOST_USER_GET_PROTOCOL_FEATURES:
288 need_reply = 1;
289 break;
290
291 case VHOST_USER_SET_STATUS:
292 if (!(dev->status & VIRTIO_CONFIG_STATUS_FEATURES_OK) ||
293 (!(dev->protocol_features &
294 (1ULL << VHOST_USER_PROTOCOL_F_STATUS))))
295 return -ENOTSUP;
296
297 if (has_reply_ack)
298 msg.flags |= VHOST_USER_NEED_REPLY_MASK;
299 /* Fallthrough */
300 case VHOST_USER_SET_FEATURES:
301 case VHOST_USER_SET_PROTOCOL_FEATURES:
302 case VHOST_USER_SET_LOG_BASE:
303 msg.payload.u64 = *((__u64 *)arg);
304 msg.size = sizeof(m.payload.u64);
305 break;
306
307 case VHOST_USER_SET_OWNER:
308 case VHOST_USER_RESET_OWNER:
309 break;
310
311 case VHOST_USER_SET_MEM_TABLE:
312 if (prepare_vhost_memory_user(&msg, fds) < 0)
313 return -1;
314 fd_num = msg.payload.memory.nregions;
315 msg.size = sizeof(m.payload.memory.nregions);
316 msg.size += sizeof(m.payload.memory.padding);
317 msg.size += fd_num * sizeof(struct vhost_memory_region);
318
319 if (has_reply_ack)
320 msg.flags |= VHOST_USER_NEED_REPLY_MASK;
321 break;
322
323 case VHOST_USER_SET_LOG_FD:
324 fds[fd_num++] = *((int *)arg);
325 break;
326
327 case VHOST_USER_SET_VRING_NUM:
328 case VHOST_USER_SET_VRING_BASE:
329 case VHOST_USER_SET_VRING_ENABLE:
330 memcpy(&msg.payload.state, arg, sizeof(msg.payload.state));
331 msg.size = sizeof(m.payload.state);
332 break;
333
334 case VHOST_USER_GET_VRING_BASE:
335 memcpy(&msg.payload.state, arg, sizeof(msg.payload.state));
336 msg.size = sizeof(m.payload.state);
337 need_reply = 1;
338 break;
339
340 case VHOST_USER_SET_VRING_ADDR:
341 memcpy(&msg.payload.addr, arg, sizeof(msg.payload.addr));
342 msg.size = sizeof(m.payload.addr);
343 break;
344
345 case VHOST_USER_SET_VRING_KICK:
346 case VHOST_USER_SET_VRING_CALL:
347 case VHOST_USER_SET_VRING_ERR:
348 file = arg;
349 msg.payload.u64 = file->index & VHOST_USER_VRING_IDX_MASK;
350 msg.size = sizeof(m.payload.u64);
351 if (file->fd > 0)
352 fds[fd_num++] = file->fd;
353 else
354 msg.payload.u64 |= VHOST_USER_VRING_NOFD_MASK;
355 break;
356
357 default:
358 PMD_DRV_LOG(ERR, "trying to send unhandled msg type");
359 return -1;
360 }
361
362 len = VHOST_USER_HDR_SIZE + msg.size;
363 if (vhost_user_write(vhostfd, &msg, len, fds, fd_num) < 0) {
364 PMD_DRV_LOG(ERR, "%s failed: %s",
365 vhost_msg_strings[req], strerror(errno));
366 return -1;
367 }
368
369 if (need_reply || msg.flags & VHOST_USER_NEED_REPLY_MASK) {
370 if (vhost_user_read(vhostfd, &msg) < 0) {
371 PMD_DRV_LOG(ERR, "Received msg failed: %s",
372 strerror(errno));
373 return -1;
374 }
375
376 if (req != msg.request) {
377 PMD_DRV_LOG(ERR, "Received unexpected msg type");
378 return -1;
379 }
380
381 switch (req) {
382 case VHOST_USER_GET_FEATURES:
383 case VHOST_USER_GET_STATUS:
384 case VHOST_USER_GET_PROTOCOL_FEATURES:
385 if (msg.size != sizeof(m.payload.u64)) {
386 PMD_DRV_LOG(ERR, "Received bad msg size");
387 return -1;
388 }
389 *((__u64 *)arg) = msg.payload.u64;
390 break;
391 case VHOST_USER_GET_VRING_BASE:
392 if (msg.size != sizeof(m.payload.state)) {
393 PMD_DRV_LOG(ERR, "Received bad msg size");
394 return -1;
395 }
396 memcpy(arg, &msg.payload.state,
397 sizeof(struct vhost_vring_state));
398 break;
399 default:
400 /* Reply-ack handling */
401 if (msg.size != sizeof(m.payload.u64)) {
402 PMD_DRV_LOG(ERR, "Received bad msg size");
403 return -1;
404 }
405
406 if (msg.payload.u64 != 0) {
407 PMD_DRV_LOG(ERR, "Slave replied NACK");
408 return -1;
409 }
410
411 break;
412 }
413 }
414
415 return 0;
416 }
417
418 #define MAX_VIRTIO_USER_BACKLOG 1
419 static int
virtio_user_start_server(struct virtio_user_dev * dev,struct sockaddr_un * un)420 virtio_user_start_server(struct virtio_user_dev *dev, struct sockaddr_un *un)
421 {
422 int ret;
423 int flag;
424 int fd = dev->listenfd;
425
426 ret = bind(fd, (struct sockaddr *)un, sizeof(*un));
427 if (ret < 0) {
428 PMD_DRV_LOG(ERR, "failed to bind to %s: %s; remove it and try again\n",
429 dev->path, strerror(errno));
430 return -1;
431 }
432 ret = listen(fd, MAX_VIRTIO_USER_BACKLOG);
433 if (ret < 0)
434 return -1;
435
436 flag = fcntl(fd, F_GETFL);
437 if (fcntl(fd, F_SETFL, flag | O_NONBLOCK) < 0) {
438 PMD_DRV_LOG(ERR, "fcntl failed, %s", strerror(errno));
439 return -1;
440 }
441
442 return 0;
443 }
444
445 /**
446 * Set up environment to talk with a vhost user backend.
447 *
448 * @return
449 * - (-1) if fail;
450 * - (0) if succeed.
451 */
452 static int
vhost_user_setup(struct virtio_user_dev * dev)453 vhost_user_setup(struct virtio_user_dev *dev)
454 {
455 int fd;
456 int flag;
457 struct sockaddr_un un;
458
459 fd = socket(AF_UNIX, SOCK_STREAM, 0);
460 if (fd < 0) {
461 PMD_DRV_LOG(ERR, "socket() error, %s", strerror(errno));
462 return -1;
463 }
464
465 flag = fcntl(fd, F_GETFD);
466 if (fcntl(fd, F_SETFD, flag | FD_CLOEXEC) < 0)
467 PMD_DRV_LOG(WARNING, "fcntl failed, %s", strerror(errno));
468
469 memset(&un, 0, sizeof(un));
470 un.sun_family = AF_UNIX;
471 strlcpy(un.sun_path, dev->path, sizeof(un.sun_path));
472
473 if (dev->is_server) {
474 dev->listenfd = fd;
475 if (virtio_user_start_server(dev, &un) < 0) {
476 PMD_DRV_LOG(ERR, "virtio-user startup fails in server mode");
477 close(fd);
478 return -1;
479 }
480 dev->vhostfd = -1;
481 } else {
482 if (connect(fd, (struct sockaddr *)&un, sizeof(un)) < 0) {
483 PMD_DRV_LOG(ERR, "connect error, %s", strerror(errno));
484 close(fd);
485 return -1;
486 }
487 dev->vhostfd = fd;
488 }
489
490 return 0;
491 }
492
493 static int
vhost_user_enable_queue_pair(struct virtio_user_dev * dev,uint16_t pair_idx,int enable)494 vhost_user_enable_queue_pair(struct virtio_user_dev *dev,
495 uint16_t pair_idx,
496 int enable)
497 {
498 int i;
499
500 if (dev->qp_enabled[pair_idx] == enable)
501 return 0;
502
503 for (i = 0; i < 2; ++i) {
504 struct vhost_vring_state state = {
505 .index = pair_idx * 2 + i,
506 .num = enable,
507 };
508
509 if (vhost_user_sock(dev, VHOST_USER_SET_VRING_ENABLE, &state))
510 return -1;
511 }
512
513 dev->qp_enabled[pair_idx] = enable;
514 return 0;
515 }
516
517 struct virtio_user_backend_ops virtio_ops_user = {
518 .setup = vhost_user_setup,
519 .send_request = vhost_user_sock,
520 .enable_qp = vhost_user_enable_queue_pair
521 };
522