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         bool extbuf;
  44         bool linearbuf;
  45
  46         /*
  47          * The "supported_features" indicates the feature bits the
  48          * vhost driver supports. The "features" indicates the feature
  49          * bits after the rte_vhost_driver_features_disable/enable().
  50          * It is also the final feature bits used for vhost-user
  51          * features negotiation.
  52          */
  53         uint64_t supported_features;
  54         uint64_t features;
  55
  56         uint64_t protocol_features;
  57
  58         /*
  59          * Device id to identify a specific backend device.
  60          * It's set to -1 for the default software implementation.
  61          * If valid, one socket can have 1 connection only.
  62          */
  63         int vdpa_dev_id;
  64
  65         struct vhost_device_ops const *notify_ops;
  66 };
  67
  68 struct vhost_user_connection {
  69         struct vhost_user_socket *vsocket;
  70         int connfd;
  71         int vid;
  72
  73         TAILQ_ENTRY(vhost_user_connection) next;
  74 };
  75
  76 #define MAX_VHOST_SOCKET 1024
  77 struct vhost_user {
  78         struct vhost_user_socket *vsockets[MAX_VHOST_SOCKET];
  79         struct fdset fdset;
  80         int vsocket_cnt;
  81         pthread_mutex_t mutex;
  82 };
  83
  84 #define MAX_VIRTIO_BACKLOG 128
  85
  86 static void vhost_user_server_new_connection(int fd, void *data, int *remove);
  87 static void vhost_user_read_cb(int fd, void *dat, int *remove);
  88 static int create_unix_socket(struct vhost_user_socket *vsocket);
  89 static int vhost_user_start_client(struct vhost_user_socket *vsocket);
  90
  91 static struct vhost_user vhost_user = {
  92         .fdset = {
  93                 .fd = { [0 ... MAX_FDS - 1] = {-1, NULL, NULL, NULL, 0} },
  94                 .fd_mutex = PTHREAD_MUTEX_INITIALIZER,
  95                 .fd_pooling_mutex = PTHREAD_MUTEX_INITIALIZER,
  96                 .num = 0
  97         },
  98         .vsocket_cnt = 0,
  99         .mutex = PTHREAD_MUTEX_INITIALIZER,
 100 };
 101
 102 /*
 103  * return bytes# of read on success or negative val on failure. Update fdnum
 104  * with number of fds read.
 105  */
 106 int
 107 read_fd_message(int sockfd, char *buf, int buflen, int *fds, int max_fds,
 108                 int *fd_num)
 109 {
 110         struct iovec iov;
 111         struct msghdr msgh;
 112         char control[CMSG_SPACE(max_fds * sizeof(int))];
 113         struct cmsghdr *cmsg;
 114         int got_fds = 0;
 115         int ret;
 116
 117         *fd_num = 0;
 118
 119         memset(&msgh, 0, sizeof(msgh));
 120         iov.iov_base = buf;
 121         iov.iov_len  = buflen;
 122
 123         msgh.msg_iov = &iov;
 124         msgh.msg_iovlen = 1;
 125         msgh.msg_control = control;
 126         msgh.msg_controllen = sizeof(control);
 127
 128         ret = recvmsg(sockfd, &msgh, 0);
 129         if (ret <= 0) {
 130                 RTE_LOG(ERR, VHOST_CONFIG, "recvmsg failed\n");
 131                 return ret;
 132         }
 133
 134         if (msgh.msg_flags & (MSG_TRUNC | MSG_CTRUNC)) {
 135                 RTE_LOG(ERR, VHOST_CONFIG, "truncted msg\n");
 136                 return -1;
 137         }
 138
 139         for (cmsg = CMSG_FIRSTHDR(&msgh); cmsg != NULL;
 140                 cmsg = CMSG_NXTHDR(&msgh, cmsg)) {
 141                 if ((cmsg->cmsg_level == SOL_SOCKET) &&
 142                         (cmsg->cmsg_type == SCM_RIGHTS)) {
 143                         got_fds = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int);
 144                         *fd_num = got_fds;
 145                         memcpy(fds, CMSG_DATA(cmsg), got_fds * sizeof(int));
 146                         break;
 147                 }
 148         }
 149
 150         /* Clear out unused file descriptors */
 151         while (got_fds < max_fds)
 152                 fds[got_fds++] = -1;
 153
 154         return ret;
 155 }
 156
 157 int
 158 send_fd_message(int sockfd, char *buf, int buflen, int *fds, int fd_num)
 159 {
 160
 161         struct iovec iov;
 162         struct msghdr msgh;
 163         size_t fdsize = fd_num * sizeof(int);
 164         char control[CMSG_SPACE(fdsize)];
 165         struct cmsghdr *cmsg;
 166         int ret;
 167
 168         memset(&msgh, 0, sizeof(msgh));
 169         iov.iov_base = buf;
 170         iov.iov_len = buflen;
 171
 172         msgh.msg_iov = &iov;
 173         msgh.msg_iovlen = 1;
 174
 175         if (fds && fd_num > 0) {
 176                 msgh.msg_control = control;
 177                 msgh.msg_controllen = sizeof(control);
 178                 cmsg = CMSG_FIRSTHDR(&msgh);
 179                 if (cmsg == NULL) {
 180                         RTE_LOG(ERR, VHOST_CONFIG, "cmsg == NULL\n");
 181                         errno = EINVAL;
 182                         return -1;
 183                 }
 184                 cmsg->cmsg_len = CMSG_LEN(fdsize);
 185                 cmsg->cmsg_level = SOL_SOCKET;
 186                 cmsg->cmsg_type = SCM_RIGHTS;
 187                 memcpy(CMSG_DATA(cmsg), fds, fdsize);
 188         } else {
 189                 msgh.msg_control = NULL;
 190                 msgh.msg_controllen = 0;
 191         }
 192
 193         do {
 194                 ret = sendmsg(sockfd, &msgh, MSG_NOSIGNAL);
 195         } while (ret < 0 && errno == EINTR);
 196
 197         if (ret < 0) {
 198                 RTE_LOG(ERR, VHOST_CONFIG,  "sendmsg error\n");
 199                 return ret;
 200         }
 201
 202         return ret;
 203 }
 204
 205 static void
 206 vhost_user_add_connection(int fd, struct vhost_user_socket *vsocket)
 207 {
 208         int vid;
 209         size_t size;
 210         struct vhost_user_connection *conn;
 211         int ret;
 212
 213         if (vsocket == NULL)
 214                 return;
 215
 216         conn = malloc(sizeof(*conn));
 217         if (conn == NULL) {
 218                 close(fd);
 219                 return;
 220         }
 221
 222         vid = vhost_new_device();
 223         if (vid == -1) {
 224                 goto err;
 225         }
 226
 227         size = strnlen(vsocket->path, PATH_MAX);
 228         vhost_set_ifname(vid, vsocket->path, size);
 229
 230         vhost_set_builtin_virtio_net(vid, vsocket->use_builtin_virtio_net);
 231
 232         vhost_attach_vdpa_device(vid, vsocket->vdpa_dev_id);
 233
 234         if (vsocket->dequeue_zero_copy)
 235                 vhost_enable_dequeue_zero_copy(vid);
 236
 237         if (vsocket->extbuf)
 238                 vhost_enable_extbuf(vid);
 239
 240         if (vsocket->linearbuf)
 241                 vhost_enable_linearbuf(vid);
 242
 243         RTE_LOG(INFO, VHOST_CONFIG, "new device, handle is %d\n", vid);
 244
 245         if (vsocket->notify_ops->new_connection) {
 246                 ret = vsocket->notify_ops->new_connection(vid);
 247                 if (ret < 0) {
 248                         RTE_LOG(ERR, VHOST_CONFIG,
 249                                 "failed to add vhost user connection with fd %d\n",
 250                                 fd);
 251                         goto err_cleanup;
 252                 }
 253         }
 254
 255         conn->connfd = fd;
 256         conn->vsocket = vsocket;
 257         conn->vid = vid;
 258         ret = fdset_add(&vhost_user.fdset, fd, vhost_user_read_cb,
 259                         NULL, conn);
 260         if (ret < 0) {
 261                 RTE_LOG(ERR, VHOST_CONFIG,
 262                         "failed to add fd %d into vhost server fdset\n",
 263                         fd);
 264
 265                 if (vsocket->notify_ops->destroy_connection)
 266                         vsocket->notify_ops->destroy_connection(conn->vid);
 267
 268                 goto err_cleanup;
 269         }
 270
 271         pthread_mutex_lock(&vsocket->conn_mutex);
 272         TAILQ_INSERT_TAIL(&vsocket->conn_list, conn, next);
 273         pthread_mutex_unlock(&vsocket->conn_mutex);
 274
 275         fdset_pipe_notify(&vhost_user.fdset);
 276         return;
 277
 278 err_cleanup:
 279         vhost_destroy_device(vid);
 280 err:
 281         free(conn);
 282         close(fd);
 283 }
 284
 285 /* call back when there is new vhost-user connection from client  */
 286 static void
 287 vhost_user_server_new_connection(int fd, void *dat, int *remove __rte_unused)
 288 {
 289         struct vhost_user_socket *vsocket = dat;
 290
 291         fd = accept(fd, NULL, NULL);
 292         if (fd < 0)
 293                 return;
 294
 295         RTE_LOG(INFO, VHOST_CONFIG, "new vhost user connection is %d\n", fd);
 296         vhost_user_add_connection(fd, vsocket);
 297 }
 298
 299 static void
 300 vhost_user_read_cb(int connfd, void *dat, int *remove)
 301 {
 302         struct vhost_user_connection *conn = dat;
 303         struct vhost_user_socket *vsocket = conn->vsocket;
 304         int ret;
 305
 306         ret = vhost_user_msg_handler(conn->vid, connfd);
 307         if (ret < 0) {
 308                 struct virtio_net *dev = get_device(conn->vid);
 309
 310                 close(connfd);
 311                 *remove = 1;
 312
 313                 if (dev)
 314                         vhost_destroy_device_notify(dev);
 315
 316                 if (vsocket->notify_ops->destroy_connection)
 317                         vsocket->notify_ops->destroy_connection(conn->vid);
 318
 319                 vhost_destroy_device(conn->vid);
 320
 321                 pthread_mutex_lock(&vsocket->conn_mutex);
 322                 TAILQ_REMOVE(&vsocket->conn_list, conn, next);
 323                 pthread_mutex_unlock(&vsocket->conn_mutex);
 324
 325                 free(conn);
 326
 327                 if (vsocket->reconnect) {
 328                         create_unix_socket(vsocket);
 329                         vhost_user_start_client(vsocket);
 330                 }
 331         }
 332 }
 333
 334 static int
 335 create_unix_socket(struct vhost_user_socket *vsocket)
 336 {
 337         int fd;
 338         struct sockaddr_un *un = &vsocket->un;
 339
 340         fd = socket(AF_UNIX, SOCK_STREAM, 0);
 341         if (fd < 0)
 342                 return -1;
 343         RTE_LOG(INFO, VHOST_CONFIG, "vhost-user %s: socket created, fd: %d\n",
 344                 vsocket->is_server ? "server" : "client", fd);
 345
 346         if (!vsocket->is_server && fcntl(fd, F_SETFL, O_NONBLOCK)) {
 347                 RTE_LOG(ERR, VHOST_CONFIG,
 348                         "vhost-user: can't set nonblocking mode for socket, fd: "
 349                         "%d (%s)\n", fd, strerror(errno));
 350                 close(fd);
 351                 return -1;
 352         }
 353
 354         memset(un, 0, sizeof(*un));
 355         un->sun_family = AF_UNIX;
 356         strncpy(un->sun_path, vsocket->path, sizeof(un->sun_path));
 357         un->sun_path[sizeof(un->sun_path) - 1] = '\0';
 358
 359         vsocket->socket_fd = fd;
 360         return 0;
 361 }
 362
 363 static int
 364 vhost_user_start_server(struct vhost_user_socket *vsocket)
 365 {
 366         int ret;
 367         int fd = vsocket->socket_fd;
 368         const char *path = vsocket->path;
 369
 370         /*
 371          * bind () may fail if the socket file with the same name already
 372          * exists. But the library obviously should not delete the file
 373          * provided by the user, since we can not be sure that it is not
 374          * being used by other applications. Moreover, many applications form
 375          * socket names based on user input, which is prone to errors.
 376          *
 377          * The user must ensure that the socket does not exist before
 378          * registering the vhost driver in server mode.
 379          */
 380         ret = bind(fd, (struct sockaddr *)&vsocket->un, sizeof(vsocket->un));
 381         if (ret < 0) {
 382                 RTE_LOG(ERR, VHOST_CONFIG,
 383                         "failed to bind to %s: %s; remove it and try again\n",
 384                         path, strerror(errno));
 385                 goto err;
 386         }
 387         RTE_LOG(INFO, VHOST_CONFIG, "bind to %s\n", path);
 388
 389         ret = listen(fd, MAX_VIRTIO_BACKLOG);
 390         if (ret < 0)
 391                 goto err;
 392
 393         ret = fdset_add(&vhost_user.fdset, fd, vhost_user_server_new_connection,
 394                   NULL, vsocket);
 395         if (ret < 0) {
 396                 RTE_LOG(ERR, VHOST_CONFIG,
 397                         "failed to add listen fd %d to vhost server fdset\n",
 398                         fd);
 399                 goto err;
 400         }
 401
 402         return 0;
 403
 404 err:
 405         close(fd);
 406         return -1;
 407 }
 408
 409 struct vhost_user_reconnect {
 410         struct sockaddr_un un;
 411         int fd;
 412         struct vhost_user_socket *vsocket;
 413
 414         TAILQ_ENTRY(vhost_user_reconnect) next;
 415 };
 416
 417 TAILQ_HEAD(vhost_user_reconnect_tailq_list, vhost_user_reconnect);
 418 struct vhost_user_reconnect_list {
 419         struct vhost_user_reconnect_tailq_list head;
 420         pthread_mutex_t mutex;
 421 };
 422
 423 static struct vhost_user_reconnect_list reconn_list;
 424 static pthread_t reconn_tid;
 425
 426 static int
 427 vhost_user_connect_nonblock(int fd, struct sockaddr *un, size_t sz)
 428 {
 429         int ret, flags;
 430
 431         ret = connect(fd, un, sz);
 432         if (ret < 0 && errno != EISCONN)
 433                 return -1;
 434
 435         flags = fcntl(fd, F_GETFL, 0);
 436         if (flags < 0) {
 437                 RTE_LOG(ERR, VHOST_CONFIG,
 438                         "can't get flags for connfd %d\n", fd);
 439                 return -2;
 440         }
 441         if ((flags & O_NONBLOCK) && fcntl(fd, F_SETFL, flags & ~O_NONBLOCK)) {
 442                 RTE_LOG(ERR, VHOST_CONFIG,
 443                                 "can't disable nonblocking on fd %d\n", fd);
 444                 return -2;
 445         }
 446         return 0;
 447 }
 448
 449 static void *
 450 vhost_user_client_reconnect(void *arg __rte_unused)
 451 {
 452         int ret;
 453         struct vhost_user_reconnect *reconn, *next;
 454
 455         while (1) {
 456                 pthread_mutex_lock(&reconn_list.mutex);
 457
 458                 /*
 459                  * An equal implementation of TAILQ_FOREACH_SAFE,
 460                  * which does not exist on all platforms.
 461                  */
 462                 for (reconn = TAILQ_FIRST(&reconn_list.head);
 463                      reconn != NULL; reconn = next) {
 464                         next = TAILQ_NEXT(reconn, next);
 465
 466                         ret = vhost_user_connect_nonblock(reconn->fd,
 467                                                 (struct sockaddr *)&reconn->un,
 468                                                 sizeof(reconn->un));
 469                         if (ret == -2) {
 470                                 close(reconn->fd);
 471                                 RTE_LOG(ERR, VHOST_CONFIG,
 472                                         "reconnection for fd %d failed\n",
 473                                         reconn->fd);
 474                                 goto remove_fd;
 475                         }
 476                         if (ret == -1)
 477                                 continue;
 478
 479                         RTE_LOG(INFO, VHOST_CONFIG,
 480                                 "%s: connected\n", reconn->vsocket->path);
 481                         vhost_user_add_connection(reconn->fd, reconn->vsocket);
 482 remove_fd:
 483                         TAILQ_REMOVE(&reconn_list.head, reconn, next);
 484                         free(reconn);
 485                 }
 486
 487                 pthread_mutex_unlock(&reconn_list.mutex);
 488                 sleep(1);
 489         }
 490
 491         return NULL;
 492 }
 493
 494 static int
 495 vhost_user_reconnect_init(void)
 496 {
 497         int ret;
 498
 499         ret = pthread_mutex_init(&reconn_list.mutex, NULL);
 500         if (ret < 0) {
 501                 RTE_LOG(ERR, VHOST_CONFIG, "failed to initialize mutex");
 502                 return ret;
 503         }
 504         TAILQ_INIT(&reconn_list.head);
 505
 506         ret = rte_ctrl_thread_create(&reconn_tid, "vhost_reconn", NULL,
 507                              vhost_user_client_reconnect, NULL);
 508         if (ret != 0) {
 509                 RTE_LOG(ERR, VHOST_CONFIG, "failed to create reconnect thread");
 510                 if (pthread_mutex_destroy(&reconn_list.mutex)) {
 511                         RTE_LOG(ERR, VHOST_CONFIG,
 512                                 "failed to destroy reconnect mutex");
 513                 }
 514         }
 515
 516         return ret;
 517 }
 518
 519 static int
 520 vhost_user_start_client(struct vhost_user_socket *vsocket)
 521 {
 522         int ret;
 523         int fd = vsocket->socket_fd;
 524         const char *path = vsocket->path;
 525         struct vhost_user_reconnect *reconn;
 526
 527         ret = vhost_user_connect_nonblock(fd, (struct sockaddr *)&vsocket->un,
 528                                           sizeof(vsocket->un));
 529         if (ret == 0) {
 530                 vhost_user_add_connection(fd, vsocket);
 531                 return 0;
 532         }
 533
 534         RTE_LOG(WARNING, VHOST_CONFIG,
 535                 "failed to connect to %s: %s\n",
 536                 path, strerror(errno));
 537
 538         if (ret == -2 || !vsocket->reconnect) {
 539                 close(fd);
 540                 return -1;
 541         }
 542
 543         RTE_LOG(INFO, VHOST_CONFIG, "%s: reconnecting...\n", path);
 544         reconn = malloc(sizeof(*reconn));
 545         if (reconn == NULL) {
 546                 RTE_LOG(ERR, VHOST_CONFIG,
 547                         "failed to allocate memory for reconnect\n");
 548                 close(fd);
 549                 return -1;
 550         }
 551         reconn->un = vsocket->un;
 552         reconn->fd = fd;
 553         reconn->vsocket = vsocket;
 554         pthread_mutex_lock(&reconn_list.mutex);
 555         TAILQ_INSERT_TAIL(&reconn_list.head, reconn, next);
 556         pthread_mutex_unlock(&reconn_list.mutex);
 557
 558         return 0;
 559 }
 560
 561 static struct vhost_user_socket *
 562 find_vhost_user_socket(const char *path)
 563 {
 564         int i;
 565
 566         if (path == NULL)
 567                 return NULL;
 568
 569         for (i = 0; i < vhost_user.vsocket_cnt; i++) {
 570                 struct vhost_user_socket *vsocket = vhost_user.vsockets[i];
 571
 572                 if (!strcmp(vsocket->path, path))
 573                         return vsocket;
 574         }
 575
 576         return NULL;
 577 }
 578
 579 int
 580 rte_vhost_driver_attach_vdpa_device(const char *path, int did)
 581 {
 582         struct vhost_user_socket *vsocket;
 583
 584         if (rte_vdpa_get_device(did) == NULL || path == NULL)
 585                 return -1;
 586
 587         pthread_mutex_lock(&vhost_user.mutex);
 588         vsocket = find_vhost_user_socket(path);
 589         if (vsocket)
 590                 vsocket->vdpa_dev_id = did;
 591         pthread_mutex_unlock(&vhost_user.mutex);
 592
 593         return vsocket ? 0 : -1;
 594 }
 595
 596 int
 597 rte_vhost_driver_detach_vdpa_device(const char *path)
 598 {
 599         struct vhost_user_socket *vsocket;
 600
 601         pthread_mutex_lock(&vhost_user.mutex);
 602         vsocket = find_vhost_user_socket(path);
 603         if (vsocket)
 604                 vsocket->vdpa_dev_id = -1;
 605         pthread_mutex_unlock(&vhost_user.mutex);
 606
 607         return vsocket ? 0 : -1;
 608 }
 609
 610 int
 611 rte_vhost_driver_get_vdpa_device_id(const char *path)
 612 {
 613         struct vhost_user_socket *vsocket;
 614         int did = -1;
 615
 616         pthread_mutex_lock(&vhost_user.mutex);
 617         vsocket = find_vhost_user_socket(path);
 618         if (vsocket)
 619                 did = vsocket->vdpa_dev_id;
 620         pthread_mutex_unlock(&vhost_user.mutex);
 621
 622         return did;
 623 }
 624
 625 int
 626 rte_vhost_driver_disable_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
 633         /* Note that use_builtin_virtio_net is not affected by this function
 634          * since callers may want to selectively disable features of the
 635          * built-in vhost net device backend.
 636          */
 637
 638         if (vsocket)
 639                 vsocket->features &= ~features;
 640         pthread_mutex_unlock(&vhost_user.mutex);
 641
 642         return vsocket ? 0 : -1;
 643 }
 644
 645 int
 646 rte_vhost_driver_enable_features(const char *path, uint64_t features)
 647 {
 648         struct vhost_user_socket *vsocket;
 649
 650         pthread_mutex_lock(&vhost_user.mutex);
 651         vsocket = find_vhost_user_socket(path);
 652         if (vsocket) {
 653                 if ((vsocket->supported_features & features) != features) {
 654                         /*
 655                          * trying to enable features the driver doesn't
 656                          * support.
 657                          */
 658                         pthread_mutex_unlock(&vhost_user.mutex);
 659                         return -1;
 660                 }
 661                 vsocket->features |= features;
 662         }
 663         pthread_mutex_unlock(&vhost_user.mutex);
 664
 665         return vsocket ? 0 : -1;
 666 }
 667
 668 int
 669 rte_vhost_driver_set_features(const char *path, uint64_t features)
 670 {
 671         struct vhost_user_socket *vsocket;
 672
 673         pthread_mutex_lock(&vhost_user.mutex);
 674         vsocket = find_vhost_user_socket(path);
 675         if (vsocket) {
 676                 vsocket->supported_features = features;
 677                 vsocket->features = features;
 678
 679                 /* Anyone setting feature bits is implementing their own vhost
 680                  * device backend.
 681                  */
 682                 vsocket->use_builtin_virtio_net = false;
 683         }
 684         pthread_mutex_unlock(&vhost_user.mutex);
 685
 686         return vsocket ? 0 : -1;
 687 }
 688
 689 int
 690 rte_vhost_driver_get_features(const char *path, uint64_t *features)
 691 {
 692         struct vhost_user_socket *vsocket;
 693         uint64_t vdpa_features;
 694         struct rte_vdpa_device *vdpa_dev;
 695         int did = -1;
 696         int ret = 0;
 697
 698         pthread_mutex_lock(&vhost_user.mutex);
 699         vsocket = find_vhost_user_socket(path);
 700         if (!vsocket) {
 701                 RTE_LOG(ERR, VHOST_CONFIG,
 702                         "socket file %s is not registered yet.\n", path);
 703                 ret = -1;
 704                 goto unlock_exit;
 705         }
 706
 707         did = vsocket->vdpa_dev_id;
 708         vdpa_dev = rte_vdpa_get_device(did);
 709         if (!vdpa_dev || !vdpa_dev->ops->get_features) {
 710                 *features = vsocket->features;
 711                 goto unlock_exit;
 712         }
 713
 714         if (vdpa_dev->ops->get_features(did, &vdpa_features) < 0) {
 715                 RTE_LOG(ERR, VHOST_CONFIG,
 716                                 "failed to get vdpa features "
 717                                 "for socket file %s.\n", path);
 718                 ret = -1;
 719                 goto unlock_exit;
 720         }
 721
 722         *features = vsocket->features & vdpa_features;
 723
 724 unlock_exit:
 725         pthread_mutex_unlock(&vhost_user.mutex);
 726         return ret;
 727 }
 728
 729 int
 730 rte_vhost_driver_set_protocol_features(const char *path,
 731                 uint64_t protocol_features)
 732 {
 733         struct vhost_user_socket *vsocket;
 734
 735         pthread_mutex_lock(&vhost_user.mutex);
 736         vsocket = find_vhost_user_socket(path);
 737         if (vsocket)
 738                 vsocket->protocol_features = protocol_features;
 739         pthread_mutex_unlock(&vhost_user.mutex);
 740         return vsocket ? 0 : -1;
 741 }
 742
 743 int
 744 rte_vhost_driver_get_protocol_features(const char *path,
 745                 uint64_t *protocol_features)
 746 {
 747         struct vhost_user_socket *vsocket;
 748         uint64_t vdpa_protocol_features;
 749         struct rte_vdpa_device *vdpa_dev;
 750         int did = -1;
 751         int ret = 0;
 752
 753         pthread_mutex_lock(&vhost_user.mutex);
 754         vsocket = find_vhost_user_socket(path);
 755         if (!vsocket) {
 756                 RTE_LOG(ERR, VHOST_CONFIG,
 757                         "socket file %s is not registered yet.\n", path);
 758                 ret = -1;
 759                 goto unlock_exit;
 760         }
 761
 762         did = vsocket->vdpa_dev_id;
 763         vdpa_dev = rte_vdpa_get_device(did);
 764         if (!vdpa_dev || !vdpa_dev->ops->get_protocol_features) {
 765                 *protocol_features = vsocket->protocol_features;
 766                 goto unlock_exit;
 767         }
 768
 769         if (vdpa_dev->ops->get_protocol_features(did,
 770                                 &vdpa_protocol_features) < 0) {
 771                 RTE_LOG(ERR, VHOST_CONFIG,
 772                                 "failed to get vdpa protocol features "
 773                                 "for socket file %s.\n", path);
 774                 ret = -1;
 775                 goto unlock_exit;
 776         }
 777
 778         *protocol_features = vsocket->protocol_features
 779                 & vdpa_protocol_features;
 780
 781 unlock_exit:
 782         pthread_mutex_unlock(&vhost_user.mutex);
 783         return ret;
 784 }
 785
 786 int
 787 rte_vhost_driver_get_queue_num(const char *path, uint32_t *queue_num)
 788 {
 789         struct vhost_user_socket *vsocket;
 790         uint32_t vdpa_queue_num;
 791         struct rte_vdpa_device *vdpa_dev;
 792         int did = -1;
 793         int ret = 0;
 794
 795         pthread_mutex_lock(&vhost_user.mutex);
 796         vsocket = find_vhost_user_socket(path);
 797         if (!vsocket) {
 798                 RTE_LOG(ERR, VHOST_CONFIG,
 799                         "socket file %s is not registered yet.\n", path);
 800                 ret = -1;
 801                 goto unlock_exit;
 802         }
 803
 804         did = vsocket->vdpa_dev_id;
 805         vdpa_dev = rte_vdpa_get_device(did);
 806         if (!vdpa_dev || !vdpa_dev->ops->get_queue_num) {
 807                 *queue_num = VHOST_MAX_QUEUE_PAIRS;
 808                 goto unlock_exit;
 809         }
 810
 811         if (vdpa_dev->ops->get_queue_num(did, &vdpa_queue_num) < 0) {
 812                 RTE_LOG(ERR, VHOST_CONFIG,
 813                                 "failed to get vdpa queue number "
 814                                 "for socket file %s.\n", path);
 815                 ret = -1;
 816                 goto unlock_exit;
 817         }
 818
 819         *queue_num = RTE_MIN((uint32_t)VHOST_MAX_QUEUE_PAIRS, vdpa_queue_num);
 820
 821 unlock_exit:
 822         pthread_mutex_unlock(&vhost_user.mutex);
 823         return ret;
 824 }
 825
 826 static void
 827 vhost_user_socket_mem_free(struct vhost_user_socket *vsocket)
 828 {
 829         if (vsocket && vsocket->path) {
 830                 free(vsocket->path);
 831                 vsocket->path = NULL;
 832         }
 833
 834         if (vsocket) {
 835                 free(vsocket);
 836                 vsocket = NULL;
 837         }
 838 }
 839
 840 /*
 841  * Register a new vhost-user socket; here we could act as server
 842  * (the default case), or client (when RTE_VHOST_USER_CLIENT) flag
 843  * is set.
 844  */
 845 int
 846 rte_vhost_driver_register(const char *path, uint64_t flags)
 847 {
 848         int ret = -1;
 849         struct vhost_user_socket *vsocket;
 850
 851         if (!path)
 852                 return -1;
 853
 854         pthread_mutex_lock(&vhost_user.mutex);
 855
 856         if (vhost_user.vsocket_cnt == MAX_VHOST_SOCKET) {
 857                 RTE_LOG(ERR, VHOST_CONFIG,
 858                         "error: the number of vhost sockets reaches maximum\n");
 859                 goto out;
 860         }
 861
 862         vsocket = malloc(sizeof(struct vhost_user_socket));
 863         if (!vsocket)
 864                 goto out;
 865         memset(vsocket, 0, sizeof(struct vhost_user_socket));
 866         vsocket->path = strdup(path);
 867         if (vsocket->path == NULL) {
 868                 RTE_LOG(ERR, VHOST_CONFIG,
 869                         "error: failed to copy socket path string\n");
 870                 vhost_user_socket_mem_free(vsocket);
 871                 goto out;
 872         }
 873         TAILQ_INIT(&vsocket->conn_list);
 874         ret = pthread_mutex_init(&vsocket->conn_mutex, NULL);
 875         if (ret) {
 876                 RTE_LOG(ERR, VHOST_CONFIG,
 877                         "error: failed to init connection mutex\n");
 878                 goto out_free;
 879         }
 880         vsocket->dequeue_zero_copy = flags & RTE_VHOST_USER_DEQUEUE_ZERO_COPY;
 881         vsocket->extbuf = flags & RTE_VHOST_USER_EXTBUF_SUPPORT;
 882         vsocket->linearbuf = flags & RTE_VHOST_USER_LINEARBUF_SUPPORT;
 883
 884         if (vsocket->dequeue_zero_copy &&
 885             (flags & RTE_VHOST_USER_IOMMU_SUPPORT)) {
 886                 RTE_LOG(ERR, VHOST_CONFIG,
 887                         "error: enabling dequeue zero copy and IOMMU features "
 888                         "simultaneously is not supported\n");
 889                 goto out_mutex;
 890         }
 891
 892         /*
 893          * Set the supported features correctly for the builtin vhost-user
 894          * net driver.
 895          *
 896          * Applications know nothing about features the builtin virtio net
 897          * driver (virtio_net.c) supports, thus it's not possible for them
 898          * to invoke rte_vhost_driver_set_features(). To workaround it, here
 899          * we set it unconditionally. If the application want to implement
 900          * another vhost-user driver (say SCSI), it should call the
 901          * rte_vhost_driver_set_features(), which will overwrite following
 902          * two values.
 903          */
 904         vsocket->use_builtin_virtio_net = true;
 905         vsocket->supported_features = VIRTIO_NET_SUPPORTED_FEATURES;
 906         vsocket->features           = VIRTIO_NET_SUPPORTED_FEATURES;
 907         vsocket->protocol_features  = VHOST_USER_PROTOCOL_FEATURES;
 908
 909         /*
 910          * Dequeue zero copy can't assure descriptors returned in order.
 911          * Also, it requires that the guest memory is populated, which is
 912          * not compatible with postcopy.
 913          */
 914         if (vsocket->dequeue_zero_copy) {
 915                 if (vsocket->extbuf) {
 916                         RTE_LOG(ERR, VHOST_CONFIG,
 917                         "error: zero copy is incompatible with external buffers\n");
 918                         ret = -1;
 919                         goto out_mutex;
 920                 }
 921                 if (vsocket->linearbuf) {
 922                         RTE_LOG(ERR, VHOST_CONFIG,
 923                         "error: zero copy is incompatible with linear buffers\n");
 924                         ret = -1;
 925                         goto out_mutex;
 926                 }
 927                 vsocket->supported_features &= ~(1ULL << VIRTIO_F_IN_ORDER);
 928                 vsocket->features &= ~(1ULL << VIRTIO_F_IN_ORDER);
 929
 930                 RTE_LOG(INFO, VHOST_CONFIG,
 931                         "Dequeue zero copy requested, disabling postcopy support\n");
 932                 vsocket->protocol_features &=
 933                         ~(1ULL << VHOST_USER_PROTOCOL_F_PAGEFAULT);
 934         }
 935
 936         /*
 937          * We'll not be able to receive a buffer from guest in linear mode
 938          * without external buffer if it will not fit in a single mbuf, which is
 939          * likely if segmentation offloading enabled.
 940          */
 941         if (vsocket->linearbuf && !vsocket->extbuf) {
 942                 uint64_t seg_offload_features =
 943                                 (1ULL << VIRTIO_NET_F_HOST_TSO4) |
 944                                 (1ULL << VIRTIO_NET_F_HOST_TSO6) |
 945                                 (1ULL << VIRTIO_NET_F_HOST_UFO);
 946
 947                 RTE_LOG(INFO, VHOST_CONFIG,
 948                         "Linear buffers requested without external buffers, "
 949                         "disabling host segmentation offloading support\n");
 950                 vsocket->supported_features &= ~seg_offload_features;
 951                 vsocket->features &= ~seg_offload_features;
 952         }
 953
 954         if (!(flags & RTE_VHOST_USER_IOMMU_SUPPORT)) {
 955                 vsocket->supported_features &= ~(1ULL << VIRTIO_F_IOMMU_PLATFORM);
 956                 vsocket->features &= ~(1ULL << VIRTIO_F_IOMMU_PLATFORM);
 957         }
 958
 959         if (!(flags & RTE_VHOST_USER_POSTCOPY_SUPPORT)) {
 960                 vsocket->protocol_features &=
 961                         ~(1ULL << VHOST_USER_PROTOCOL_F_PAGEFAULT);
 962         } else {
 963 #ifndef RTE_LIBRTE_VHOST_POSTCOPY
 964                 RTE_LOG(ERR, VHOST_CONFIG,
 965                         "Postcopy requested but not compiled\n");
 966                 ret = -1;
 967                 goto out_mutex;
 968 #endif
 969         }
 970
 971         if ((flags & RTE_VHOST_USER_CLIENT) != 0) {
 972                 vsocket->reconnect = !(flags & RTE_VHOST_USER_NO_RECONNECT);
 973                 if (vsocket->reconnect && reconn_tid == 0) {
 974                         if (vhost_user_reconnect_init() != 0)
 975                                 goto out_mutex;
 976                 }
 977         } else {
 978                 vsocket->is_server = true;
 979         }
 980         ret = create_unix_socket(vsocket);
 981         if (ret < 0) {
 982                 goto out_mutex;
 983         }
 984
 985         vhost_user.vsockets[vhost_user.vsocket_cnt++] = vsocket;
 986
 987         pthread_mutex_unlock(&vhost_user.mutex);
 988         return ret;
 989
 990 out_mutex:
 991         if (pthread_mutex_destroy(&vsocket->conn_mutex)) {
 992                 RTE_LOG(ERR, VHOST_CONFIG,
 993                         "error: failed to destroy connection mutex\n");
 994         }
 995 out_free:
 996         vhost_user_socket_mem_free(vsocket);
 997 out:
 998         pthread_mutex_unlock(&vhost_user.mutex);
 999
1000         return ret;
1001 }
1002
1003 static bool
1004 vhost_user_remove_reconnect(struct vhost_user_socket *vsocket)
1005 {
1006         int found = false;
1007         struct vhost_user_reconnect *reconn, *next;
1008
1009         pthread_mutex_lock(&reconn_list.mutex);
1010
1011         for (reconn = TAILQ_FIRST(&reconn_list.head);
1012              reconn != NULL; reconn = next) {
1013                 next = TAILQ_NEXT(reconn, next);
1014
1015                 if (reconn->vsocket == vsocket) {
1016                         TAILQ_REMOVE(&reconn_list.head, reconn, next);
1017                         close(reconn->fd);
1018                         free(reconn);
1019                         found = true;
1020                         break;
1021                 }
1022         }
1023         pthread_mutex_unlock(&reconn_list.mutex);
1024         return found;
1025 }
1026
1027 /**
1028  * Unregister the specified vhost socket
1029  */
1030 int
1031 rte_vhost_driver_unregister(const char *path)
1032 {
1033         int i;
1034         int count;
1035         struct vhost_user_connection *conn, *next;
1036
1037         if (path == NULL)
1038                 return -1;
1039
1040 again:
1041         pthread_mutex_lock(&vhost_user.mutex);
1042
1043         for (i = 0; i < vhost_user.vsocket_cnt; i++) {
1044                 struct vhost_user_socket *vsocket = vhost_user.vsockets[i];
1045
1046                 if (!strcmp(vsocket->path, path)) {
1047                         pthread_mutex_lock(&vsocket->conn_mutex);
1048                         for (conn = TAILQ_FIRST(&vsocket->conn_list);
1049                              conn != NULL;
1050                              conn = next) {
1051                                 next = TAILQ_NEXT(conn, next);
1052
1053                                 /*
1054                                  * If r/wcb is executing, release the
1055                                  * conn_mutex lock, and try again since
1056                                  * the r/wcb may use the conn_mutex lock.
1057                                  */
1058                                 if (fdset_try_del(&vhost_user.fdset,
1059                                                   conn->connfd) == -1) {
1060                                         pthread_mutex_unlock(
1061                                                         &vsocket->conn_mutex);
1062                                         pthread_mutex_unlock(&vhost_user.mutex);
1063                                         goto again;
1064                                 }
1065
1066                                 RTE_LOG(INFO, VHOST_CONFIG,
1067                                         "free connfd = %d for device '%s'\n",
1068                                         conn->connfd, path);
1069                                 close(conn->connfd);
1070                                 vhost_destroy_device(conn->vid);
1071                                 TAILQ_REMOVE(&vsocket->conn_list, conn, next);
1072                                 free(conn);
1073                         }
1074                         pthread_mutex_unlock(&vsocket->conn_mutex);
1075
1076                         if (vsocket->is_server) {
1077                                 fdset_del(&vhost_user.fdset,
1078                                                 vsocket->socket_fd);
1079                                 close(vsocket->socket_fd);
1080                                 unlink(path);
1081                         } else if (vsocket->reconnect) {
1082                                 vhost_user_remove_reconnect(vsocket);
1083                         }
1084
1085                         pthread_mutex_destroy(&vsocket->conn_mutex);
1086                         vhost_user_socket_mem_free(vsocket);
1087
1088                         count = --vhost_user.vsocket_cnt;
1089                         vhost_user.vsockets[i] = vhost_user.vsockets[count];
1090                         vhost_user.vsockets[count] = NULL;
1091                         pthread_mutex_unlock(&vhost_user.mutex);
1092
1093                         return 0;
1094                 }
1095         }
1096         pthread_mutex_unlock(&vhost_user.mutex);
1097
1098         return -1;
1099 }
1100
1101 /*
1102  * Register ops so that we can add/remove device to data core.
1103  */
1104 int
1105 rte_vhost_driver_callback_register(const char *path,
1106         struct vhost_device_ops const * const ops)
1107 {
1108         struct vhost_user_socket *vsocket;
1109
1110         pthread_mutex_lock(&vhost_user.mutex);
1111         vsocket = find_vhost_user_socket(path);
1112         if (vsocket)
1113                 vsocket->notify_ops = ops;
1114         pthread_mutex_unlock(&vhost_user.mutex);
1115
1116         return vsocket ? 0 : -1;
1117 }
1118
1119 struct vhost_device_ops const *
1120 vhost_driver_callback_get(const char *path)
1121 {
1122         struct vhost_user_socket *vsocket;
1123
1124         pthread_mutex_lock(&vhost_user.mutex);
1125         vsocket = find_vhost_user_socket(path);
1126         pthread_mutex_unlock(&vhost_user.mutex);
1127
1128         return vsocket ? vsocket->notify_ops : NULL;
1129 }
1130
1131 int
1132 rte_vhost_driver_start(const char *path)
1133 {
1134         struct vhost_user_socket *vsocket;
1135         static pthread_t fdset_tid;
1136
1137         pthread_mutex_lock(&vhost_user.mutex);
1138         vsocket = find_vhost_user_socket(path);
1139         pthread_mutex_unlock(&vhost_user.mutex);
1140
1141         if (!vsocket)
1142                 return -1;
1143
1144         if (fdset_tid == 0) {
1145                 /**
1146                  * create a pipe which will be waited by poll and notified to
1147                  * rebuild the wait list of poll.
1148                  */
1149                 if (fdset_pipe_init(&vhost_user.fdset) < 0) {
1150                         RTE_LOG(ERR, VHOST_CONFIG,
1151                                 "failed to create pipe for vhost fdset\n");
1152                         return -1;
1153                 }
1154
1155                 int ret = rte_ctrl_thread_create(&fdset_tid,
1156                         "vhost-events", NULL, fdset_event_dispatch,
1157                         &vhost_user.fdset);
1158                 if (ret != 0) {
1159                         RTE_LOG(ERR, VHOST_CONFIG,
1160                                 "failed to create fdset handling thread");
1161
1162                         fdset_pipe_uninit(&vhost_user.fdset);
1163                         return -1;
1164                 }
1165         }
1166
1167         if (vsocket->is_server)
1168                 return vhost_user_start_server(vsocket);
1169         else
1170                 return vhost_user_start_client(vsocket);
1171 }