lib/librte_vhost/socket.c

   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 <limits.h>
   8 #include <stdlib.h>
   9 #include <unistd.h>
  10 #include <string.h>
  11 #include <sys/types.h>
  12 #include <sys/socket.h>
  13 #include <sys/un.h>
  14 #include <sys/queue.h>
  15 #include <errno.h>
  16 #include <fcntl.h>
  17 #include <pthread.h>
  18
  19 #include <rte_log.h>
  20
  21 #include "fd_man.h"
  22 #include "vhost.h"
  23 #include "vhost_user.h"
  24
  25
  26 TAILQ_HEAD(vhost_user_connection_list, vhost_user_connection);
  27
  28 /*
  29  * Every time rte_vhost_driver_register() is invoked, an associated
  30  * vhost_user_socket struct will be created.
  31  */
  32 struct vhost_user_socket {
  33         struct vhost_user_connection_list conn_list;
  34         pthread_mutex_t conn_mutex;
  35         char *path;
  36         int socket_fd;
  37         struct sockaddr_un un;
  38         bool is_server;
  39         bool reconnect;
  40         bool dequeue_zero_copy;
  41         bool iommu_support;
  42         bool use_builtin_virtio_net;
  43
  44         /*
  45          * The "supported_features" indicates the feature bits the
  46          * vhost driver supports. The "features" indicates the feature
  47          * bits after the rte_vhost_driver_features_disable/enable().
  48          * It is also the final feature bits used for vhost-user
  49          * features negotiation.
  50          */
  51         uint64_t supported_features;
  52         uint64_t features;
  53
  54         uint64_t protocol_features;
  55
  56         /*
  57          * Device id to identify a specific backend device.
  58          * It's set to -1 for the default software implementation.
  59          * If valid, one socket can have 1 connection only.
  60          */
  61         int vdpa_dev_id;
  62
  63         struct vhost_device_ops const *notify_ops;
  64 };
  65
  66 struct vhost_user_connection {
  67         struct vhost_user_socket *vsocket;
  68         int connfd;
  69         int vid;
  70
  71         TAILQ_ENTRY(vhost_user_connection) next;
  72 };
  73
  74 #define MAX_VHOST_SOCKET 1024
  75 struct vhost_user {
  76         struct vhost_user_socket *vsockets[MAX_VHOST_SOCKET];
  77         struct fdset fdset;
  78         int vsocket_cnt;
  79         pthread_mutex_t mutex;
  80 };
  81
  82 #define MAX_VIRTIO_BACKLOG 128
  83
  84 static void vhost_user_server_new_connection(int fd, void *data, int *remove);
  85 static void vhost_user_read_cb(int fd, void *dat, int *remove);
  86 static int create_unix_socket(struct vhost_user_socket *vsocket);
  87 static int vhost_user_start_client(struct vhost_user_socket *vsocket);
  88
  89 static struct vhost_user vhost_user = {
  90         .fdset = {
  91                 .fd = { [0 ... MAX_FDS - 1] = {-1, NULL, NULL, NULL, 0} },
  92                 .fd_mutex = PTHREAD_MUTEX_INITIALIZER,
  93                 .num = 0
  94         },
  95         .vsocket_cnt = 0,
  96         .mutex = PTHREAD_MUTEX_INITIALIZER,
  97 };
  98
  99 /*
 100  * return bytes# of read on success or negative val on failure. Update fdnum
 101  * with number of fds read.
 102  */
 103 int
 104 read_fd_message(int sockfd, char *buf, int buflen, int *fds, int max_fds,
 105                 int *fd_num)
 106 {
 107         struct iovec iov;
 108         struct msghdr msgh;
 109         char control[CMSG_SPACE(max_fds * sizeof(int))];
 110         struct cmsghdr *cmsg;
 111         int got_fds = 0;
 112         int ret;
 113
 114         *fd_num = 0;
 115
 116         memset(&msgh, 0, sizeof(msgh));
 117         iov.iov_base = buf;
 118         iov.iov_len  = buflen;
 119
 120         msgh.msg_iov = &iov;
 121         msgh.msg_iovlen = 1;
 122         msgh.msg_control = control;
 123         msgh.msg_controllen = sizeof(control);
 124
 125         ret = recvmsg(sockfd, &msgh, 0);
 126         if (ret <= 0) {
 127                 RTE_LOG(ERR, VHOST_CONFIG, "recvmsg failed\n");
 128                 return ret;
 129         }
 130
 131         if (msgh.msg_flags & (MSG_TRUNC | MSG_CTRUNC)) {
 132                 RTE_LOG(ERR, VHOST_CONFIG, "truncted msg\n");
 133                 return -1;
 134         }
 135
 136         for (cmsg = CMSG_FIRSTHDR(&msgh); cmsg != NULL;
 137                 cmsg = CMSG_NXTHDR(&msgh, cmsg)) {
 138                 if ((cmsg->cmsg_level == SOL_SOCKET) &&
 139                         (cmsg->cmsg_type == SCM_RIGHTS)) {
 140                         got_fds = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int);
 141                         *fd_num = got_fds;
 142                         memcpy(fds, CMSG_DATA(cmsg), got_fds * sizeof(int));
 143                         break;
 144                 }
 145         }
 146
 147         /* Clear out unused file descriptors */
 148         while (got_fds < max_fds)
 149                 fds[got_fds++] = -1;
 150
 151         return ret;
 152 }
 153
 154 int
 155 send_fd_message(int sockfd, char *buf, int buflen, int *fds, int fd_num)
 156 {
 157
 158         struct iovec iov;
 159         struct msghdr msgh;
 160         size_t fdsize = fd_num * sizeof(int);
 161         char control[CMSG_SPACE(fdsize)];
 162         struct cmsghdr *cmsg;
 163         int ret;
 164
 165         memset(&msgh, 0, sizeof(msgh));
 166         iov.iov_base = buf;
 167         iov.iov_len = buflen;
 168
 169         msgh.msg_iov = &iov;
 170         msgh.msg_iovlen = 1;
 171
 172         if (fds && fd_num > 0) {
 173                 msgh.msg_control = control;
 174                 msgh.msg_controllen = sizeof(control);
 175                 cmsg = CMSG_FIRSTHDR(&msgh);
 176                 if (cmsg == NULL) {
 177                         RTE_LOG(ERR, VHOST_CONFIG, "cmsg == NULL\n");
 178                         errno = EINVAL;
 179                         return -1;
 180                 }
 181                 cmsg->cmsg_len = CMSG_LEN(fdsize);
 182                 cmsg->cmsg_level = SOL_SOCKET;
 183                 cmsg->cmsg_type = SCM_RIGHTS;
 184                 memcpy(CMSG_DATA(cmsg), fds, fdsize);
 185         } else {
 186                 msgh.msg_control = NULL;
 187                 msgh.msg_controllen = 0;
 188         }
 189
 190         do {
 191                 ret = sendmsg(sockfd, &msgh, MSG_NOSIGNAL);
 192         } while (ret < 0 && errno == EINTR);
 193
 194         if (ret < 0) {
 195                 RTE_LOG(ERR, VHOST_CONFIG,  "sendmsg error\n");
 196                 return ret;
 197         }
 198
 199         return ret;
 200 }
 201
 202 static void
 203 vhost_user_add_connection(int fd, struct vhost_user_socket *vsocket)
 204 {
 205         int vid;
 206         size_t size;
 207         struct vhost_user_connection *conn;
 208         int ret;
 209
 210         if (vsocket == NULL)
 211                 return;
 212
 213         conn = malloc(sizeof(*conn));
 214         if (conn == NULL) {
 215                 close(fd);
 216                 return;
 217         }
 218
 219         vid = vhost_new_device();
 220         if (vid == -1) {
 221                 goto err;
 222         }
 223
 224         size = strnlen(vsocket->path, PATH_MAX);
 225         vhost_set_ifname(vid, vsocket->path, size);
 226
 227         vhost_set_builtin_virtio_net(vid, vsocket->use_builtin_virtio_net);
 228
 229         vhost_attach_vdpa_device(vid, vsocket->vdpa_dev_id);
 230
 231         if (vsocket->dequeue_zero_copy)
 232                 vhost_enable_dequeue_zero_copy(vid);
 233
 234         RTE_LOG(INFO, VHOST_CONFIG, "new device, handle is %d\n", vid);
 235
 236         if (vsocket->notify_ops->new_connection) {
 237                 ret = vsocket->notify_ops->new_connection(vid);
 238                 if (ret < 0) {
 239                         RTE_LOG(ERR, VHOST_CONFIG,
 240                                 "failed to add vhost user connection with fd %d\n",
 241                                 fd);
 242                         goto err;
 243                 }
 244         }
 245
 246         conn->connfd = fd;
 247         conn->vsocket = vsocket;
 248         conn->vid = vid;
 249         ret = fdset_add(&vhost_user.fdset, fd, vhost_user_read_cb,
 250                         NULL, conn);
 251         if (ret < 0) {
 252                 RTE_LOG(ERR, VHOST_CONFIG,
 253                         "failed to add fd %d into vhost server fdset\n",
 254                         fd);
 255
 256                 if (vsocket->notify_ops->destroy_connection)
 257                         vsocket->notify_ops->destroy_connection(conn->vid);
 258
 259                 goto err;
 260         }
 261
 262         pthread_mutex_lock(&vsocket->conn_mutex);
 263         TAILQ_INSERT_TAIL(&vsocket->conn_list, conn, next);
 264         pthread_mutex_unlock(&vsocket->conn_mutex);
 265
 266         fdset_pipe_notify(&vhost_user.fdset);
 267         return;
 268
 269 err:
 270         free(conn);
 271         close(fd);
 272 }
 273
 274 /* call back when there is new vhost-user connection from client  */
 275 static void
 276 vhost_user_server_new_connection(int fd, void *dat, int *remove __rte_unused)
 277 {
 278         struct vhost_user_socket *vsocket = dat;
 279
 280         fd = accept(fd, NULL, NULL);
 281         if (fd < 0)
 282                 return;
 283
 284         RTE_LOG(INFO, VHOST_CONFIG, "new vhost user connection is %d\n", fd);
 285         vhost_user_add_connection(fd, vsocket);
 286 }
 287
 288 static void
 289 vhost_user_read_cb(int connfd, void *dat, int *remove)
 290 {
 291         struct vhost_user_connection *conn = dat;
 292         struct vhost_user_socket *vsocket = conn->vsocket;
 293         int ret;
 294
 295         ret = vhost_user_msg_handler(conn->vid, connfd);
 296         if (ret < 0) {
 297                 close(connfd);
 298                 *remove = 1;
 299                 vhost_destroy_device(conn->vid);
 300
 301                 if (vsocket->notify_ops->destroy_connection)
 302                         vsocket->notify_ops->destroy_connection(conn->vid);
 303
 304                 pthread_mutex_lock(&vsocket->conn_mutex);
 305                 TAILQ_REMOVE(&vsocket->conn_list, conn, next);
 306                 pthread_mutex_unlock(&vsocket->conn_mutex);
 307
 308                 free(conn);
 309
 310                 if (vsocket->reconnect) {
 311                         create_unix_socket(vsocket);
 312                         vhost_user_start_client(vsocket);
 313                 }
 314         }
 315 }
 316
 317 static int
 318 create_unix_socket(struct vhost_user_socket *vsocket)
 319 {
 320         int fd;
 321         struct sockaddr_un *un = &vsocket->un;
 322
 323         fd = socket(AF_UNIX, SOCK_STREAM, 0);
 324         if (fd < 0)
 325                 return -1;
 326         RTE_LOG(INFO, VHOST_CONFIG, "vhost-user %s: socket created, fd: %d\n",
 327                 vsocket->is_server ? "server" : "client", fd);
 328
 329         if (!vsocket->is_server && fcntl(fd, F_SETFL, O_NONBLOCK)) {
 330                 RTE_LOG(ERR, VHOST_CONFIG,
 331                         "vhost-user: can't set nonblocking mode for socket, fd: "
 332                         "%d (%s)\n", fd, strerror(errno));
 333                 close(fd);
 334                 return -1;
 335         }
 336
 337         memset(un, 0, sizeof(*un));
 338         un->sun_family = AF_UNIX;
 339         strncpy(un->sun_path, vsocket->path, sizeof(un->sun_path));
 340         un->sun_path[sizeof(un->sun_path) - 1] = '\0';
 341
 342         vsocket->socket_fd = fd;
 343         return 0;
 344 }
 345
 346 static int
 347 vhost_user_start_server(struct vhost_user_socket *vsocket)
 348 {
 349         int ret;
 350         int fd = vsocket->socket_fd;
 351         const char *path = vsocket->path;
 352
 353         /*
 354          * bind () may fail if the socket file with the same name already
 355          * exists. But the library obviously should not delete the file
 356          * provided by the user, since we can not be sure that it is not
 357          * being used by other applications. Moreover, many applications form
 358          * socket names based on user input, which is prone to errors.
 359          *
 360          * The user must ensure that the socket does not exist before
 361          * registering the vhost driver in server mode.
 362          */
 363         ret = bind(fd, (struct sockaddr *)&vsocket->un, sizeof(vsocket->un));
 364         if (ret < 0) {
 365                 RTE_LOG(ERR, VHOST_CONFIG,
 366                         "failed to bind to %s: %s; remove it and try again\n",
 367                         path, strerror(errno));
 368                 goto err;
 369         }
 370         RTE_LOG(INFO, VHOST_CONFIG, "bind to %s\n", path);
 371
 372         ret = listen(fd, MAX_VIRTIO_BACKLOG);
 373         if (ret < 0)
 374                 goto err;
 375
 376         ret = fdset_add(&vhost_user.fdset, fd, vhost_user_server_new_connection,
 377                   NULL, vsocket);
 378         if (ret < 0) {
 379                 RTE_LOG(ERR, VHOST_CONFIG,
 380                         "failed to add listen fd %d to vhost server fdset\n",
 381                         fd);
 382                 goto err;
 383         }
 384
 385         return 0;
 386
 387 err:
 388         close(fd);
 389         return -1;
 390 }
 391
 392 struct vhost_user_reconnect {
 393         struct sockaddr_un un;
 394         int fd;
 395         struct vhost_user_socket *vsocket;
 396
 397         TAILQ_ENTRY(vhost_user_reconnect) next;
 398 };
 399
 400 TAILQ_HEAD(vhost_user_reconnect_tailq_list, vhost_user_reconnect);
 401 struct vhost_user_reconnect_list {
 402         struct vhost_user_reconnect_tailq_list head;
 403         pthread_mutex_t mutex;
 404 };
 405
 406 static struct vhost_user_reconnect_list reconn_list;
 407 static pthread_t reconn_tid;
 408
 409 static int
 410 vhost_user_connect_nonblock(int fd, struct sockaddr *un, size_t sz)
 411 {
 412         int ret, flags;
 413
 414         ret = connect(fd, un, sz);
 415         if (ret < 0 && errno != EISCONN)
 416                 return -1;
 417
 418         flags = fcntl(fd, F_GETFL, 0);
 419         if (flags < 0) {
 420                 RTE_LOG(ERR, VHOST_CONFIG,
 421                         "can't get flags for connfd %d\n", fd);
 422                 return -2;
 423         }
 424         if ((flags & O_NONBLOCK) && fcntl(fd, F_SETFL, flags & ~O_NONBLOCK)) {
 425                 RTE_LOG(ERR, VHOST_CONFIG,
 426                                 "can't disable nonblocking on fd %d\n", fd);
 427                 return -2;
 428         }
 429         return 0;
 430 }
 431
 432 static void *
 433 vhost_user_client_reconnect(void *arg __rte_unused)
 434 {
 435         int ret;
 436         struct vhost_user_reconnect *reconn, *next;
 437
 438         while (1) {
 439                 pthread_mutex_lock(&reconn_list.mutex);
 440
 441                 /*
 442                  * An equal implementation of TAILQ_FOREACH_SAFE,
 443                  * which does not exist on all platforms.
 444                  */
 445                 for (reconn = TAILQ_FIRST(&reconn_list.head);
 446                      reconn != NULL; reconn = next) {
 447                         next = TAILQ_NEXT(reconn, next);
 448
 449                         ret = vhost_user_connect_nonblock(reconn->fd,
 450                                                 (struct sockaddr *)&reconn->un,
 451                                                 sizeof(reconn->un));
 452                         if (ret == -2) {
 453                                 close(reconn->fd);
 454                                 RTE_LOG(ERR, VHOST_CONFIG,
 455                                         "reconnection for fd %d failed\n",
 456                                         reconn->fd);
 457                                 goto remove_fd;
 458                         }
 459                         if (ret == -1)
 460                                 continue;
 461
 462                         RTE_LOG(INFO, VHOST_CONFIG,
 463                                 "%s: connected\n", reconn->vsocket->path);
 464                         vhost_user_add_connection(reconn->fd, reconn->vsocket);
 465 remove_fd:
 466                         TAILQ_REMOVE(&reconn_list.head, reconn, next);
 467                         free(reconn);
 468                 }
 469
 470                 pthread_mutex_unlock(&reconn_list.mutex);
 471                 sleep(1);
 472         }
 473
 474         return NULL;
 475 }
 476
 477 static int
 478 vhost_user_reconnect_init(void)
 479 {
 480         int ret;
 481
 482         ret = pthread_mutex_init(&reconn_list.mutex, NULL);
 483         if (ret < 0) {
 484                 RTE_LOG(ERR, VHOST_CONFIG, "failed to initialize mutex");
 485                 return ret;
 486         }
 487         TAILQ_INIT(&reconn_list.head);
 488
 489         ret = rte_ctrl_thread_create(&reconn_tid, "vhost_reconn", NULL,
 490                              vhost_user_client_reconnect, NULL);
 491         if (ret != 0) {
 492                 RTE_LOG(ERR, VHOST_CONFIG, "failed to create reconnect thread");
 493                 if (pthread_mutex_destroy(&reconn_list.mutex)) {
 494                         RTE_LOG(ERR, VHOST_CONFIG,
 495                                 "failed to destroy reconnect mutex");
 496                 }
 497         }
 498
 499         return ret;
 500 }
 501
 502 static int
 503 vhost_user_start_client(struct vhost_user_socket *vsocket)
 504 {
 505         int ret;
 506         int fd = vsocket->socket_fd;
 507         const char *path = vsocket->path;
 508         struct vhost_user_reconnect *reconn;
 509
 510         ret = vhost_user_connect_nonblock(fd, (struct sockaddr *)&vsocket->un,
 511                                           sizeof(vsocket->un));
 512         if (ret == 0) {
 513                 vhost_user_add_connection(fd, vsocket);
 514                 return 0;
 515         }
 516
 517         RTE_LOG(WARNING, VHOST_CONFIG,
 518                 "failed to connect to %s: %s\n",
 519                 path, strerror(errno));
 520
 521         if (ret == -2 || !vsocket->reconnect) {
 522                 close(fd);
 523                 return -1;
 524         }
 525
 526         RTE_LOG(INFO, VHOST_CONFIG, "%s: reconnecting...\n", path);
 527         reconn = malloc(sizeof(*reconn));
 528         if (reconn == NULL) {
 529                 RTE_LOG(ERR, VHOST_CONFIG,
 530                         "failed to allocate memory for reconnect\n");
 531                 close(fd);
 532                 return -1;
 533         }
 534         reconn->un = vsocket->un;
 535         reconn->fd = fd;
 536         reconn->vsocket = vsocket;
 537         pthread_mutex_lock(&reconn_list.mutex);
 538         TAILQ_INSERT_TAIL(&reconn_list.head, reconn, next);
 539         pthread_mutex_unlock(&reconn_list.mutex);
 540
 541         return 0;
 542 }
 543
 544 static struct vhost_user_socket *
 545 find_vhost_user_socket(const char *path)
 546 {
 547         int i;
 548
 549         for (i = 0; i < vhost_user.vsocket_cnt; i++) {
 550                 struct vhost_user_socket *vsocket = vhost_user.vsockets[i];
 551
 552                 if (!strcmp(vsocket->path, path))
 553                         return vsocket;
 554         }
 555
 556         return NULL;
 557 }
 558
 559 int
 560 rte_vhost_driver_attach_vdpa_device(const char *path, int did)
 561 {
 562         struct vhost_user_socket *vsocket;
 563
 564         if (rte_vdpa_get_device(did) == NULL)
 565                 return -1;
 566
 567         pthread_mutex_lock(&vhost_user.mutex);
 568         vsocket = find_vhost_user_socket(path);
 569         if (vsocket)
 570                 vsocket->vdpa_dev_id = did;
 571         pthread_mutex_unlock(&vhost_user.mutex);
 572
 573         return vsocket ? 0 : -1;
 574 }
 575
 576 int
 577 rte_vhost_driver_detach_vdpa_device(const char *path)
 578 {
 579         struct vhost_user_socket *vsocket;
 580
 581         pthread_mutex_lock(&vhost_user.mutex);
 582         vsocket = find_vhost_user_socket(path);
 583         if (vsocket)
 584                 vsocket->vdpa_dev_id = -1;
 585         pthread_mutex_unlock(&vhost_user.mutex);
 586
 587         return vsocket ? 0 : -1;
 588 }
 589
 590 int
 591 rte_vhost_driver_get_vdpa_device_id(const char *path)
 592 {
 593         struct vhost_user_socket *vsocket;
 594         int did = -1;
 595
 596         pthread_mutex_lock(&vhost_user.mutex);
 597         vsocket = find_vhost_user_socket(path);
 598         if (vsocket)
 599                 did = vsocket->vdpa_dev_id;
 600         pthread_mutex_unlock(&vhost_user.mutex);
 601
 602         return did;
 603 }
 604
 605 int
 606 rte_vhost_driver_disable_features(const char *path, uint64_t features)
 607 {
 608         struct vhost_user_socket *vsocket;
 609
 610         pthread_mutex_lock(&vhost_user.mutex);
 611         vsocket = find_vhost_user_socket(path);
 612
 613         /* Note that use_builtin_virtio_net is not affected by this function
 614          * since callers may want to selectively disable features of the
 615          * built-in vhost net device backend.
 616          */
 617
 618         if (vsocket)
 619                 vsocket->features &= ~features;
 620         pthread_mutex_unlock(&vhost_user.mutex);
 621
 622         return vsocket ? 0 : -1;
 623 }
 624
 625 int
 626 rte_vhost_driver_enable_features(const char *path, uint64_t features)
 627 {
 628         struct vhost_user_socket *vsocket;
 629
 630         pthread_mutex_lock(&vhost_user.mutex);
 631         vsocket = find_vhost_user_socket(path);
 632         if (vsocket) {
 633                 if ((vsocket->supported_features & features) != features) {
 634                         /*
 635                          * trying to enable features the driver doesn't
 636                          * support.
 637                          */
 638                         pthread_mutex_unlock(&vhost_user.mutex);
 639                         return -1;
 640                 }
 641                 vsocket->features |= features;
 642         }
 643         pthread_mutex_unlock(&vhost_user.mutex);
 644
 645         return vsocket ? 0 : -1;
 646 }
 647
 648 int
 649 rte_vhost_driver_set_features(const char *path, uint64_t features)
 650 {
 651         struct vhost_user_socket *vsocket;
 652
 653         pthread_mutex_lock(&vhost_user.mutex);
 654         vsocket = find_vhost_user_socket(path);
 655         if (vsocket) {
 656                 vsocket->supported_features = features;
 657                 vsocket->features = features;
 658
 659                 /* Anyone setting feature bits is implementing their own vhost
 660                  * device backend.
 661                  */
 662                 vsocket->use_builtin_virtio_net = false;
 663         }
 664         pthread_mutex_unlock(&vhost_user.mutex);
 665
 666         return vsocket ? 0 : -1;
 667 }
 668
 669 int
 670 rte_vhost_driver_get_features(const char *path, uint64_t *features)
 671 {
 672         struct vhost_user_socket *vsocket;
 673         uint64_t vdpa_features;
 674         struct rte_vdpa_device *vdpa_dev;
 675         int did = -1;
 676         int ret = 0;
 677
 678         pthread_mutex_lock(&vhost_user.mutex);
 679         vsocket = find_vhost_user_socket(path);
 680         if (!vsocket) {
 681                 RTE_LOG(ERR, VHOST_CONFIG,
 682                         "socket file %s is not registered yet.\n", path);
 683                 ret = -1;
 684                 goto unlock_exit;
 685         }
 686
 687         did = vsocket->vdpa_dev_id;
 688         vdpa_dev = rte_vdpa_get_device(did);
 689         if (!vdpa_dev || !vdpa_dev->ops->get_features) {
 690                 *features = vsocket->features;
 691                 goto unlock_exit;
 692         }
 693
 694         if (vdpa_dev->ops->get_features(did, &vdpa_features) < 0) {
 695                 RTE_LOG(ERR, VHOST_CONFIG,
 696                                 "failed to get vdpa features "
 697                                 "for socket file %s.\n", path);
 698                 ret = -1;
 699                 goto unlock_exit;
 700         }
 701
 702         *features = vsocket->features & vdpa_features;
 703
 704 unlock_exit:
 705         pthread_mutex_unlock(&vhost_user.mutex);
 706         return ret;
 707 }
 708
 709 int
 710 rte_vhost_driver_get_protocol_features(const char *path,
 711                 uint64_t *protocol_features)
 712 {
 713         struct vhost_user_socket *vsocket;
 714         uint64_t vdpa_protocol_features;
 715         struct rte_vdpa_device *vdpa_dev;
 716         int did = -1;
 717         int ret = 0;
 718
 719         pthread_mutex_lock(&vhost_user.mutex);
 720         vsocket = find_vhost_user_socket(path);
 721         if (!vsocket) {
 722                 RTE_LOG(ERR, VHOST_CONFIG,
 723                         "socket file %s is not registered yet.\n", path);
 724                 ret = -1;
 725                 goto unlock_exit;
 726         }
 727
 728         did = vsocket->vdpa_dev_id;
 729         vdpa_dev = rte_vdpa_get_device(did);
 730         if (!vdpa_dev || !vdpa_dev->ops->get_protocol_features) {
 731                 *protocol_features = vsocket->protocol_features;
 732                 goto unlock_exit;
 733         }
 734
 735         if (vdpa_dev->ops->get_protocol_features(did,
 736                                 &vdpa_protocol_features) < 0) {
 737                 RTE_LOG(ERR, VHOST_CONFIG,
 738                                 "failed to get vdpa protocol features "
 739                                 "for socket file %s.\n", path);
 740                 ret = -1;
 741                 goto unlock_exit;
 742         }
 743
 744         *protocol_features = vsocket->protocol_features
 745                 & vdpa_protocol_features;
 746
 747 unlock_exit:
 748         pthread_mutex_unlock(&vhost_user.mutex);
 749         return ret;
 750 }
 751
 752 int
 753 rte_vhost_driver_get_queue_num(const char *path, uint32_t *queue_num)
 754 {
 755         struct vhost_user_socket *vsocket;
 756         uint32_t vdpa_queue_num;
 757         struct rte_vdpa_device *vdpa_dev;
 758         int did = -1;
 759         int ret = 0;
 760
 761         pthread_mutex_lock(&vhost_user.mutex);
 762         vsocket = find_vhost_user_socket(path);
 763         if (!vsocket) {
 764                 RTE_LOG(ERR, VHOST_CONFIG,
 765                         "socket file %s is not registered yet.\n", path);
 766                 ret = -1;
 767                 goto unlock_exit;
 768         }
 769
 770         did = vsocket->vdpa_dev_id;
 771         vdpa_dev = rte_vdpa_get_device(did);
 772         if (!vdpa_dev || !vdpa_dev->ops->get_queue_num) {
 773                 *queue_num = VHOST_MAX_QUEUE_PAIRS;
 774                 goto unlock_exit;
 775         }
 776
 777         if (vdpa_dev->ops->get_queue_num(did, &vdpa_queue_num) < 0) {
 778                 RTE_LOG(ERR, VHOST_CONFIG,
 779                                 "failed to get vdpa queue number "
 780                                 "for socket file %s.\n", path);
 781                 ret = -1;
 782                 goto unlock_exit;
 783         }
 784
 785         *queue_num = RTE_MIN((uint32_t)VHOST_MAX_QUEUE_PAIRS, vdpa_queue_num);
 786
 787 unlock_exit:
 788         pthread_mutex_unlock(&vhost_user.mutex);
 789         return ret;
 790 }
 791
 792 static void
 793 vhost_user_socket_mem_free(struct vhost_user_socket *vsocket)
 794 {
 795         if (vsocket && vsocket->path) {
 796                 free(vsocket->path);
 797                 vsocket->path = NULL;
 798         }
 799
 800         if (vsocket) {
 801                 free(vsocket);
 802                 vsocket = NULL;
 803         }
 804 }
 805
 806 /*
 807  * Register a new vhost-user socket; here we could act as server
 808  * (the default case), or client (when RTE_VHOST_USER_CLIENT) flag
 809  * is set.
 810  */
 811 int
 812 rte_vhost_driver_register(const char *path, uint64_t flags)
 813 {
 814         int ret = -1;
 815         struct vhost_user_socket *vsocket;
 816
 817         if (!path)
 818                 return -1;
 819
 820         pthread_mutex_lock(&vhost_user.mutex);
 821
 822         if (vhost_user.vsocket_cnt == MAX_VHOST_SOCKET) {
 823                 RTE_LOG(ERR, VHOST_CONFIG,
 824                         "error: the number of vhost sockets reaches maximum\n");
 825                 goto out;
 826         }
 827
 828         vsocket = malloc(sizeof(struct vhost_user_socket));
 829         if (!vsocket)
 830                 goto out;
 831         memset(vsocket, 0, sizeof(struct vhost_user_socket));
 832         vsocket->path = strdup(path);
 833         if (vsocket->path == NULL) {
 834                 RTE_LOG(ERR, VHOST_CONFIG,
 835                         "error: failed to copy socket path string\n");
 836                 vhost_user_socket_mem_free(vsocket);
 837                 goto out;
 838         }
 839         TAILQ_INIT(&vsocket->conn_list);
 840         ret = pthread_mutex_init(&vsocket->conn_mutex, NULL);
 841         if (ret) {
 842                 RTE_LOG(ERR, VHOST_CONFIG,
 843                         "error: failed to init connection mutex\n");
 844                 goto out_free;
 845         }
 846         vsocket->dequeue_zero_copy = flags & RTE_VHOST_USER_DEQUEUE_ZERO_COPY;
 847
 848         /*
 849          * Set the supported features correctly for the builtin vhost-user
 850          * net driver.
 851          *
 852          * Applications know nothing about features the builtin virtio net
 853          * driver (virtio_net.c) supports, thus it's not possible for them
 854          * to invoke rte_vhost_driver_set_features(). To workaround it, here
 855          * we set it unconditionally. If the application want to implement
 856          * another vhost-user driver (say SCSI), it should call the
 857          * rte_vhost_driver_set_features(), which will overwrite following
 858          * two values.
 859          */
 860         vsocket->use_builtin_virtio_net = true;
 861         vsocket->supported_features = VIRTIO_NET_SUPPORTED_FEATURES;
 862         vsocket->features           = VIRTIO_NET_SUPPORTED_FEATURES;
 863         vsocket->protocol_features  = VHOST_USER_PROTOCOL_FEATURES;
 864
 865         /*
 866          * Dequeue zero copy can't assure descriptors returned in order.
 867          * Also, it requires that the guest memory is populated, which is
 868          * not compatible with postcopy.
 869          */
 870         if (vsocket->dequeue_zero_copy) {
 871                 vsocket->supported_features &= ~(1ULL << VIRTIO_F_IN_ORDER);
 872                 vsocket->features &= ~(1ULL << VIRTIO_F_IN_ORDER);
 873
 874                 RTE_LOG(INFO, VHOST_CONFIG,
 875                         "Dequeue zero copy requested, disabling postcopy support\n");
 876                 vsocket->protocol_features &=
 877                         ~(1ULL << VHOST_USER_PROTOCOL_F_PAGEFAULT);
 878         }
 879
 880         if (!(flags & RTE_VHOST_USER_IOMMU_SUPPORT)) {
 881                 vsocket->supported_features &= ~(1ULL << VIRTIO_F_IOMMU_PLATFORM);
 882                 vsocket->features &= ~(1ULL << VIRTIO_F_IOMMU_PLATFORM);
 883         }
 884
 885         if (!(flags & RTE_VHOST_USER_POSTCOPY_SUPPORT)) {
 886                 vsocket->protocol_features &=
 887                         ~(1ULL << VHOST_USER_PROTOCOL_F_PAGEFAULT);
 888         } else {
 889 #ifndef RTE_LIBRTE_VHOST_POSTCOPY
 890                 RTE_LOG(ERR, VHOST_CONFIG,
 891                         "Postcopy requested but not compiled\n");
 892                 ret = -1;
 893                 goto out_mutex;
 894 #endif
 895         }
 896
 897         if ((flags & RTE_VHOST_USER_CLIENT) != 0) {
 898                 vsocket->reconnect = !(flags & RTE_VHOST_USER_NO_RECONNECT);
 899                 if (vsocket->reconnect && reconn_tid == 0) {
 900                         if (vhost_user_reconnect_init() != 0)
 901                                 goto out_mutex;
 902                 }
 903         } else {
 904                 vsocket->is_server = true;
 905         }
 906         ret = create_unix_socket(vsocket);
 907         if (ret < 0) {
 908                 goto out_mutex;
 909         }
 910
 911         vhost_user.vsockets[vhost_user.vsocket_cnt++] = vsocket;
 912
 913         pthread_mutex_unlock(&vhost_user.mutex);
 914         return ret;
 915
 916 out_mutex:
 917         if (pthread_mutex_destroy(&vsocket->conn_mutex)) {
 918                 RTE_LOG(ERR, VHOST_CONFIG,
 919                         "error: failed to destroy connection mutex\n");
 920         }
 921 out_free:
 922         vhost_user_socket_mem_free(vsocket);
 923 out:
 924         pthread_mutex_unlock(&vhost_user.mutex);
 925
 926         return ret;
 927 }
 928
 929 static bool
 930 vhost_user_remove_reconnect(struct vhost_user_socket *vsocket)
 931 {
 932         int found = false;
 933         struct vhost_user_reconnect *reconn, *next;
 934
 935         pthread_mutex_lock(&reconn_list.mutex);
 936
 937         for (reconn = TAILQ_FIRST(&reconn_list.head);
 938              reconn != NULL; reconn = next) {
 939                 next = TAILQ_NEXT(reconn, next);
 940
 941                 if (reconn->vsocket == vsocket) {
 942                         TAILQ_REMOVE(&reconn_list.head, reconn, next);
 943                         close(reconn->fd);
 944                         free(reconn);
 945                         found = true;
 946                         break;
 947                 }
 948         }
 949         pthread_mutex_unlock(&reconn_list.mutex);
 950         return found;
 951 }
 952
 953 /**
 954  * Unregister the specified vhost socket
 955  */
 956 int
 957 rte_vhost_driver_unregister(const char *path)
 958 {
 959         int i;
 960         int count;
 961         struct vhost_user_connection *conn, *next;
 962
 963         pthread_mutex_lock(&vhost_user.mutex);
 964
 965         for (i = 0; i < vhost_user.vsocket_cnt; i++) {
 966                 struct vhost_user_socket *vsocket = vhost_user.vsockets[i];
 967
 968                 if (!strcmp(vsocket->path, path)) {
 969 again:
 970                         pthread_mutex_lock(&vsocket->conn_mutex);
 971                         for (conn = TAILQ_FIRST(&vsocket->conn_list);
 972                              conn != NULL;
 973                              conn = next) {
 974                                 next = TAILQ_NEXT(conn, next);
 975
 976                                 /*
 977                                  * If r/wcb is executing, release the
 978                                  * conn_mutex lock, and try again since
 979                                  * the r/wcb may use the conn_mutex lock.
 980                                  */
 981                                 if (fdset_try_del(&vhost_user.fdset,
 982                                                   conn->connfd) == -1) {
 983                                         pthread_mutex_unlock(
 984                                                         &vsocket->conn_mutex);
 985                                         goto again;
 986                                 }
 987
 988                                 RTE_LOG(INFO, VHOST_CONFIG,
 989                                         "free connfd = %d for device '%s'\n",
 990                                         conn->connfd, path);
 991                                 close(conn->connfd);
 992                                 vhost_destroy_device(conn->vid);
 993                                 TAILQ_REMOVE(&vsocket->conn_list, conn, next);
 994                                 free(conn);
 995                         }
 996                         pthread_mutex_unlock(&vsocket->conn_mutex);
 997
 998                         if (vsocket->is_server) {
 999                                 fdset_del(&vhost_user.fdset,
1000                                                 vsocket->socket_fd);
1001                                 close(vsocket->socket_fd);
1002                                 unlink(path);
1003                         } else if (vsocket->reconnect) {
1004                                 vhost_user_remove_reconnect(vsocket);
1005                         }
1006
1007                         pthread_mutex_destroy(&vsocket->conn_mutex);
1008                         vhost_user_socket_mem_free(vsocket);
1009
1010                         count = --vhost_user.vsocket_cnt;
1011                         vhost_user.vsockets[i] = vhost_user.vsockets[count];
1012                         vhost_user.vsockets[count] = NULL;
1013                         pthread_mutex_unlock(&vhost_user.mutex);
1014
1015                         return 0;
1016                 }
1017         }
1018         pthread_mutex_unlock(&vhost_user.mutex);
1019
1020         return -1;
1021 }
1022
1023 /*
1024  * Register ops so that we can add/remove device to data core.
1025  */
1026 int
1027 rte_vhost_driver_callback_register(const char *path,
1028         struct vhost_device_ops const * const ops)
1029 {
1030         struct vhost_user_socket *vsocket;
1031
1032         pthread_mutex_lock(&vhost_user.mutex);
1033         vsocket = find_vhost_user_socket(path);
1034         if (vsocket)
1035                 vsocket->notify_ops = ops;
1036         pthread_mutex_unlock(&vhost_user.mutex);
1037
1038         return vsocket ? 0 : -1;
1039 }
1040
1041 struct vhost_device_ops const *
1042 vhost_driver_callback_get(const char *path)
1043 {
1044         struct vhost_user_socket *vsocket;
1045
1046         pthread_mutex_lock(&vhost_user.mutex);
1047         vsocket = find_vhost_user_socket(path);
1048         pthread_mutex_unlock(&vhost_user.mutex);
1049
1050         return vsocket ? vsocket->notify_ops : NULL;
1051 }
1052
1053 int
1054 rte_vhost_driver_start(const char *path)
1055 {
1056         struct vhost_user_socket *vsocket;
1057         static pthread_t fdset_tid;
1058
1059         pthread_mutex_lock(&vhost_user.mutex);
1060         vsocket = find_vhost_user_socket(path);
1061         pthread_mutex_unlock(&vhost_user.mutex);
1062
1063         if (!vsocket)
1064                 return -1;
1065
1066         if (fdset_tid == 0) {
1067                 /**
1068                  * create a pipe which will be waited by poll and notified to
1069                  * rebuild the wait list of poll.
1070                  */
1071                 if (fdset_pipe_init(&vhost_user.fdset) < 0) {
1072                         RTE_LOG(ERR, VHOST_CONFIG,
1073                                 "failed to create pipe for vhost fdset\n");
1074                         return -1;
1075                 }
1076
1077                 int ret = rte_ctrl_thread_create(&fdset_tid,
1078                         "vhost-events", NULL, fdset_event_dispatch,
1079                         &vhost_user.fdset);
1080                 if (ret != 0) {
1081                         RTE_LOG(ERR, VHOST_CONFIG,
1082                                 "failed to create fdset handling thread");
1083
1084                         fdset_pipe_uninit(&vhost_user.fdset);
1085                         return -1;
1086                 }
1087         }
1088
1089         if (vsocket->is_server)
1090                 return vhost_user_start_server(vsocket);
1091         else
1092                 return vhost_user_start_client(vsocket);
1093 }