lib/librte_vhost/socket.c

   1 /*-
   2  *   BSD LICENSE
   3  *
   4  *   Copyright(c) 2010-2016 Intel Corporation. All rights reserved.
   5  *   All rights reserved.
   6  *
   7  *   Redistribution and use in source and binary forms, with or without
   8  *   modification, are permitted provided that the following conditions
   9  *   are met:
  10  *
  11  *     * Redistributions of source code must retain the above copyright
  12  *       notice, this list of conditions and the following disclaimer.
  13  *     * Redistributions in binary form must reproduce the above copyright
  14  *       notice, this list of conditions and the following disclaimer in
  15  *       the documentation and/or other materials provided with the
  16  *       distribution.
  17  *     * Neither the name of Intel Corporation nor the names of its
  18  *       contributors may be used to endorse or promote products derived
  19  *       from this software without specific prior written permission.
  20  *
  21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 #include <stdint.h>
  35 #include <stdio.h>
  36 #include <stdbool.h>
  37 #include <limits.h>
  38 #include <stdlib.h>
  39 #include <unistd.h>
  40 #include <string.h>
  41 #include <sys/types.h>
  42 #include <sys/socket.h>
  43 #include <sys/un.h>
  44 #include <sys/queue.h>
  45 #include <errno.h>
  46 #include <fcntl.h>
  47 #include <pthread.h>
  48
  49 #include <rte_log.h>
  50
  51 #include "fd_man.h"
  52 #include "vhost.h"
  53 #include "vhost_user.h"
  54
  55 /*
  56  * Every time rte_vhost_driver_register() is invoked, an associated
  57  * vhost_user_socket struct will be created.
  58  */
  59 struct vhost_user_socket {
  60         char *path;
  61         int listenfd;
  62         int connfd;
  63         bool is_server;
  64         bool reconnect;
  65         bool dequeue_zero_copy;
  66 };
  67
  68 struct vhost_user_connection {
  69         struct vhost_user_socket *vsocket;
  70         int vid;
  71 };
  72
  73 #define MAX_VHOST_SOCKET 1024
  74 struct vhost_user {
  75         struct vhost_user_socket *vsockets[MAX_VHOST_SOCKET];
  76         struct fdset fdset;
  77         int vsocket_cnt;
  78         pthread_mutex_t mutex;
  79 };
  80
  81 #define MAX_VIRTIO_BACKLOG 128
  82
  83 static void vhost_user_server_new_connection(int fd, void *data, int *remove);
  84 static void vhost_user_read_cb(int fd, void *dat, int *remove);
  85 static int vhost_user_create_client(struct vhost_user_socket *vsocket);
  86
  87 static struct vhost_user vhost_user = {
  88         .fdset = {
  89                 .fd = { [0 ... MAX_FDS - 1] = {-1, NULL, NULL, NULL, 0} },
  90                 .fd_mutex = PTHREAD_MUTEX_INITIALIZER,
  91                 .num = 0
  92         },
  93         .vsocket_cnt = 0,
  94         .mutex = PTHREAD_MUTEX_INITIALIZER,
  95 };
  96
  97 /* return bytes# of read on success or negative val on failure. */
  98 int
  99 read_fd_message(int sockfd, char *buf, int buflen, int *fds, int fd_num)
 100 {
 101         struct iovec iov;
 102         struct msghdr msgh;
 103         size_t fdsize = fd_num * sizeof(int);
 104         char control[CMSG_SPACE(fdsize)];
 105         struct cmsghdr *cmsg;
 106         int ret;
 107
 108         memset(&msgh, 0, sizeof(msgh));
 109         iov.iov_base = buf;
 110         iov.iov_len  = buflen;
 111
 112         msgh.msg_iov = &iov;
 113         msgh.msg_iovlen = 1;
 114         msgh.msg_control = control;
 115         msgh.msg_controllen = sizeof(control);
 116
 117         ret = recvmsg(sockfd, &msgh, 0);
 118         if (ret <= 0) {
 119                 RTE_LOG(ERR, VHOST_CONFIG, "recvmsg failed\n");
 120                 return ret;
 121         }
 122
 123         if (msgh.msg_flags & (MSG_TRUNC | MSG_CTRUNC)) {
 124                 RTE_LOG(ERR, VHOST_CONFIG, "truncted msg\n");
 125                 return -1;
 126         }
 127
 128         for (cmsg = CMSG_FIRSTHDR(&msgh); cmsg != NULL;
 129                 cmsg = CMSG_NXTHDR(&msgh, cmsg)) {
 130                 if ((cmsg->cmsg_level == SOL_SOCKET) &&
 131                         (cmsg->cmsg_type == SCM_RIGHTS)) {
 132                         memcpy(fds, CMSG_DATA(cmsg), fdsize);
 133                         break;
 134                 }
 135         }
 136
 137         return ret;
 138 }
 139
 140 int
 141 send_fd_message(int sockfd, char *buf, int buflen, int *fds, int fd_num)
 142 {
 143
 144         struct iovec iov;
 145         struct msghdr msgh;
 146         size_t fdsize = fd_num * sizeof(int);
 147         char control[CMSG_SPACE(fdsize)];
 148         struct cmsghdr *cmsg;
 149         int ret;
 150
 151         memset(&msgh, 0, sizeof(msgh));
 152         iov.iov_base = buf;
 153         iov.iov_len = buflen;
 154
 155         msgh.msg_iov = &iov;
 156         msgh.msg_iovlen = 1;
 157
 158         if (fds && fd_num > 0) {
 159                 msgh.msg_control = control;
 160                 msgh.msg_controllen = sizeof(control);
 161                 cmsg = CMSG_FIRSTHDR(&msgh);
 162                 cmsg->cmsg_len = CMSG_LEN(fdsize);
 163                 cmsg->cmsg_level = SOL_SOCKET;
 164                 cmsg->cmsg_type = SCM_RIGHTS;
 165                 memcpy(CMSG_DATA(cmsg), fds, fdsize);
 166         } else {
 167                 msgh.msg_control = NULL;
 168                 msgh.msg_controllen = 0;
 169         }
 170
 171         do {
 172                 ret = sendmsg(sockfd, &msgh, 0);
 173         } while (ret < 0 && errno == EINTR);
 174
 175         if (ret < 0) {
 176                 RTE_LOG(ERR, VHOST_CONFIG,  "sendmsg error\n");
 177                 return ret;
 178         }
 179
 180         return ret;
 181 }
 182
 183 static void
 184 vhost_user_add_connection(int fd, struct vhost_user_socket *vsocket)
 185 {
 186         int vid;
 187         size_t size;
 188         struct vhost_user_connection *conn;
 189         int ret;
 190
 191         conn = malloc(sizeof(*conn));
 192         if (conn == NULL) {
 193                 close(fd);
 194                 return;
 195         }
 196
 197         vid = vhost_new_device();
 198         if (vid == -1) {
 199                 close(fd);
 200                 free(conn);
 201                 return;
 202         }
 203
 204         size = strnlen(vsocket->path, PATH_MAX);
 205         vhost_set_ifname(vid, vsocket->path, size);
 206
 207         if (vsocket->dequeue_zero_copy)
 208                 vhost_enable_dequeue_zero_copy(vid);
 209
 210         RTE_LOG(INFO, VHOST_CONFIG, "new device, handle is %d\n", vid);
 211
 212         vsocket->connfd = fd;
 213         conn->vsocket = vsocket;
 214         conn->vid = vid;
 215         ret = fdset_add(&vhost_user.fdset, fd, vhost_user_read_cb,
 216                         NULL, conn);
 217         if (ret < 0) {
 218                 vsocket->connfd = -1;
 219                 free(conn);
 220                 close(fd);
 221                 RTE_LOG(ERR, VHOST_CONFIG,
 222                         "failed to add fd %d into vhost server fdset\n",
 223                         fd);
 224         }
 225 }
 226
 227 /* call back when there is new vhost-user connection from client  */
 228 static void
 229 vhost_user_server_new_connection(int fd, void *dat, int *remove __rte_unused)
 230 {
 231         struct vhost_user_socket *vsocket = dat;
 232
 233         fd = accept(fd, NULL, NULL);
 234         if (fd < 0)
 235                 return;
 236
 237         RTE_LOG(INFO, VHOST_CONFIG, "new vhost user connection is %d\n", fd);
 238         vhost_user_add_connection(fd, vsocket);
 239 }
 240
 241 static void
 242 vhost_user_read_cb(int connfd, void *dat, int *remove)
 243 {
 244         struct vhost_user_connection *conn = dat;
 245         struct vhost_user_socket *vsocket = conn->vsocket;
 246         int ret;
 247
 248         ret = vhost_user_msg_handler(conn->vid, connfd);
 249         if (ret < 0) {
 250                 vsocket->connfd = -1;
 251                 close(connfd);
 252                 *remove = 1;
 253                 vhost_destroy_device(conn->vid);
 254                 free(conn);
 255
 256                 if (vsocket->reconnect)
 257                         vhost_user_create_client(vsocket);
 258         }
 259 }
 260
 261 static int
 262 create_unix_socket(const char *path, struct sockaddr_un *un, bool is_server)
 263 {
 264         int fd;
 265
 266         fd = socket(AF_UNIX, SOCK_STREAM, 0);
 267         if (fd < 0)
 268                 return -1;
 269         RTE_LOG(INFO, VHOST_CONFIG, "vhost-user %s: socket created, fd: %d\n",
 270                 is_server ? "server" : "client", fd);
 271
 272         if (!is_server && fcntl(fd, F_SETFL, O_NONBLOCK)) {
 273                 RTE_LOG(ERR, VHOST_CONFIG,
 274                         "vhost-user: can't set nonblocking mode for socket, fd: "
 275                         "%d (%s)\n", fd, strerror(errno));
 276                 close(fd);
 277                 return -1;
 278         }
 279
 280         memset(un, 0, sizeof(*un));
 281         un->sun_family = AF_UNIX;
 282         strncpy(un->sun_path, path, sizeof(un->sun_path));
 283         un->sun_path[sizeof(un->sun_path) - 1] = '\0';
 284
 285         return fd;
 286 }
 287
 288 static int
 289 vhost_user_create_server(struct vhost_user_socket *vsocket)
 290 {
 291         int fd;
 292         int ret;
 293         struct sockaddr_un un;
 294         const char *path = vsocket->path;
 295
 296         fd = create_unix_socket(path, &un, vsocket->is_server);
 297         if (fd < 0)
 298                 return -1;
 299
 300         ret = bind(fd, (struct sockaddr *)&un, sizeof(un));
 301         if (ret < 0) {
 302                 RTE_LOG(ERR, VHOST_CONFIG,
 303                         "failed to bind to %s: %s; remove it and try again\n",
 304                         path, strerror(errno));
 305                 goto err;
 306         }
 307         RTE_LOG(INFO, VHOST_CONFIG, "bind to %s\n", path);
 308
 309         ret = listen(fd, MAX_VIRTIO_BACKLOG);
 310         if (ret < 0)
 311                 goto err;
 312
 313         vsocket->listenfd = fd;
 314         ret = fdset_add(&vhost_user.fdset, fd, vhost_user_server_new_connection,
 315                   NULL, vsocket);
 316         if (ret < 0) {
 317                 RTE_LOG(ERR, VHOST_CONFIG,
 318                         "failed to add listen fd %d to vhost server fdset\n",
 319                         fd);
 320                 goto err;
 321         }
 322
 323         return 0;
 324
 325 err:
 326         close(fd);
 327         return -1;
 328 }
 329
 330 struct vhost_user_reconnect {
 331         struct sockaddr_un un;
 332         int fd;
 333         struct vhost_user_socket *vsocket;
 334
 335         TAILQ_ENTRY(vhost_user_reconnect) next;
 336 };
 337
 338 TAILQ_HEAD(vhost_user_reconnect_tailq_list, vhost_user_reconnect);
 339 struct vhost_user_reconnect_list {
 340         struct vhost_user_reconnect_tailq_list head;
 341         pthread_mutex_t mutex;
 342 };
 343
 344 static struct vhost_user_reconnect_list reconn_list;
 345 static pthread_t reconn_tid;
 346
 347 static int
 348 vhost_user_connect_nonblock(int fd, struct sockaddr *un, size_t sz)
 349 {
 350         int ret, flags;
 351
 352         ret = connect(fd, un, sz);
 353         if (ret < 0 && errno != EISCONN)
 354                 return -1;
 355
 356         flags = fcntl(fd, F_GETFL, 0);
 357         if (flags < 0) {
 358                 RTE_LOG(ERR, VHOST_CONFIG,
 359                         "can't get flags for connfd %d\n", fd);
 360                 return -2;
 361         }
 362         if ((flags & O_NONBLOCK) && fcntl(fd, F_SETFL, flags & ~O_NONBLOCK)) {
 363                 RTE_LOG(ERR, VHOST_CONFIG,
 364                                 "can't disable nonblocking on fd %d\n", fd);
 365                 return -2;
 366         }
 367         return 0;
 368 }
 369
 370 static void *
 371 vhost_user_client_reconnect(void *arg __rte_unused)
 372 {
 373         int ret;
 374         struct vhost_user_reconnect *reconn, *next;
 375
 376         while (1) {
 377                 pthread_mutex_lock(&reconn_list.mutex);
 378
 379                 /*
 380                  * An equal implementation of TAILQ_FOREACH_SAFE,
 381                  * which does not exist on all platforms.
 382                  */
 383                 for (reconn = TAILQ_FIRST(&reconn_list.head);
 384                      reconn != NULL; reconn = next) {
 385                         next = TAILQ_NEXT(reconn, next);
 386
 387                         ret = vhost_user_connect_nonblock(reconn->fd,
 388                                                 (struct sockaddr *)&reconn->un,
 389                                                 sizeof(reconn->un));
 390                         if (ret == -2) {
 391                                 close(reconn->fd);
 392                                 RTE_LOG(ERR, VHOST_CONFIG,
 393                                         "reconnection for fd %d failed\n",
 394                                         reconn->fd);
 395                                 goto remove_fd;
 396                         }
 397                         if (ret == -1)
 398                                 continue;
 399
 400                         RTE_LOG(INFO, VHOST_CONFIG,
 401                                 "%s: connected\n", reconn->vsocket->path);
 402                         vhost_user_add_connection(reconn->fd, reconn->vsocket);
 403 remove_fd:
 404                         TAILQ_REMOVE(&reconn_list.head, reconn, next);
 405                         free(reconn);
 406                 }
 407
 408                 pthread_mutex_unlock(&reconn_list.mutex);
 409                 sleep(1);
 410         }
 411
 412         return NULL;
 413 }
 414
 415 static int
 416 vhost_user_reconnect_init(void)
 417 {
 418         int ret;
 419
 420         pthread_mutex_init(&reconn_list.mutex, NULL);
 421         TAILQ_INIT(&reconn_list.head);
 422
 423         ret = pthread_create(&reconn_tid, NULL,
 424                              vhost_user_client_reconnect, NULL);
 425         if (ret < 0)
 426                 RTE_LOG(ERR, VHOST_CONFIG, "failed to create reconnect thread");
 427
 428         return ret;
 429 }
 430
 431 static int
 432 vhost_user_create_client(struct vhost_user_socket *vsocket)
 433 {
 434         int fd;
 435         int ret;
 436         struct sockaddr_un un;
 437         const char *path = vsocket->path;
 438         struct vhost_user_reconnect *reconn;
 439
 440         fd = create_unix_socket(path, &un, vsocket->is_server);
 441         if (fd < 0)
 442                 return -1;
 443
 444         ret = vhost_user_connect_nonblock(fd, (struct sockaddr *)&un,
 445                                           sizeof(un));
 446         if (ret == 0) {
 447                 vhost_user_add_connection(fd, vsocket);
 448                 return 0;
 449         }
 450
 451         RTE_LOG(ERR, VHOST_CONFIG,
 452                 "failed to connect to %s: %s\n",
 453                 path, strerror(errno));
 454
 455         if (ret == -2 || !vsocket->reconnect) {
 456                 close(fd);
 457                 return -1;
 458         }
 459
 460         RTE_LOG(ERR, VHOST_CONFIG, "%s: reconnecting...\n", path);
 461         reconn = malloc(sizeof(*reconn));
 462         if (reconn == NULL) {
 463                 RTE_LOG(ERR, VHOST_CONFIG,
 464                         "failed to allocate memory for reconnect\n");
 465                 close(fd);
 466                 return -1;
 467         }
 468         reconn->un = un;
 469         reconn->fd = fd;
 470         reconn->vsocket = vsocket;
 471         pthread_mutex_lock(&reconn_list.mutex);
 472         TAILQ_INSERT_TAIL(&reconn_list.head, reconn, next);
 473         pthread_mutex_unlock(&reconn_list.mutex);
 474
 475         return 0;
 476 }
 477
 478 /*
 479  * Register a new vhost-user socket; here we could act as server
 480  * (the default case), or client (when RTE_VHOST_USER_CLIENT) flag
 481  * is set.
 482  */
 483 int
 484 rte_vhost_driver_register(const char *path, uint64_t flags)
 485 {
 486         int ret = -1;
 487         struct vhost_user_socket *vsocket;
 488
 489         if (!path)
 490                 return -1;
 491
 492         pthread_mutex_lock(&vhost_user.mutex);
 493
 494         if (vhost_user.vsocket_cnt == MAX_VHOST_SOCKET) {
 495                 RTE_LOG(ERR, VHOST_CONFIG,
 496                         "error: the number of vhost sockets reaches maximum\n");
 497                 goto out;
 498         }
 499
 500         vsocket = malloc(sizeof(struct vhost_user_socket));
 501         if (!vsocket)
 502                 goto out;
 503         memset(vsocket, 0, sizeof(struct vhost_user_socket));
 504         vsocket->path = strdup(path);
 505         vsocket->connfd = -1;
 506         vsocket->dequeue_zero_copy = flags & RTE_VHOST_USER_DEQUEUE_ZERO_COPY;
 507
 508         if ((flags & RTE_VHOST_USER_CLIENT) != 0) {
 509                 vsocket->reconnect = !(flags & RTE_VHOST_USER_NO_RECONNECT);
 510                 if (vsocket->reconnect && reconn_tid == 0) {
 511                         if (vhost_user_reconnect_init() < 0) {
 512                                 free(vsocket->path);
 513                                 free(vsocket);
 514                                 goto out;
 515                         }
 516                 }
 517                 ret = vhost_user_create_client(vsocket);
 518         } else {
 519                 vsocket->is_server = true;
 520                 ret = vhost_user_create_server(vsocket);
 521         }
 522         if (ret < 0) {
 523                 free(vsocket->path);
 524                 free(vsocket);
 525                 goto out;
 526         }
 527
 528         vhost_user.vsockets[vhost_user.vsocket_cnt++] = vsocket;
 529
 530 out:
 531         pthread_mutex_unlock(&vhost_user.mutex);
 532
 533         return ret;
 534 }
 535
 536 static bool
 537 vhost_user_remove_reconnect(struct vhost_user_socket *vsocket)
 538 {
 539         int found = false;
 540         struct vhost_user_reconnect *reconn, *next;
 541
 542         pthread_mutex_lock(&reconn_list.mutex);
 543
 544         for (reconn = TAILQ_FIRST(&reconn_list.head);
 545              reconn != NULL; reconn = next) {
 546                 next = TAILQ_NEXT(reconn, next);
 547
 548                 if (reconn->vsocket == vsocket) {
 549                         TAILQ_REMOVE(&reconn_list.head, reconn, next);
 550                         close(reconn->fd);
 551                         free(reconn);
 552                         found = true;
 553                         break;
 554                 }
 555         }
 556         pthread_mutex_unlock(&reconn_list.mutex);
 557         return found;
 558 }
 559
 560 /**
 561  * Unregister the specified vhost socket
 562  */
 563 int
 564 rte_vhost_driver_unregister(const char *path)
 565 {
 566         int i;
 567         int count;
 568         struct vhost_user_connection *conn;
 569
 570         pthread_mutex_lock(&vhost_user.mutex);
 571
 572         for (i = 0; i < vhost_user.vsocket_cnt; i++) {
 573                 struct vhost_user_socket *vsocket = vhost_user.vsockets[i];
 574
 575                 if (!strcmp(vsocket->path, path)) {
 576                         if (vsocket->is_server) {
 577                                 fdset_del(&vhost_user.fdset, vsocket->listenfd);
 578                                 close(vsocket->listenfd);
 579                                 unlink(path);
 580                         } else if (vsocket->reconnect) {
 581                                 vhost_user_remove_reconnect(vsocket);
 582                         }
 583
 584                         conn = fdset_del(&vhost_user.fdset, vsocket->connfd);
 585                         if (conn) {
 586                                 RTE_LOG(INFO, VHOST_CONFIG,
 587                                         "free connfd = %d for device '%s'\n",
 588                                         vsocket->connfd, path);
 589                                 close(vsocket->connfd);
 590                                 vhost_destroy_device(conn->vid);
 591                                 free(conn);
 592                         }
 593
 594                         free(vsocket->path);
 595                         free(vsocket);
 596
 597                         count = --vhost_user.vsocket_cnt;
 598                         vhost_user.vsockets[i] = vhost_user.vsockets[count];
 599                         vhost_user.vsockets[count] = NULL;
 600                         pthread_mutex_unlock(&vhost_user.mutex);
 601
 602                         return 0;
 603                 }
 604         }
 605         pthread_mutex_unlock(&vhost_user.mutex);
 606
 607         return -1;
 608 }
 609
 610 int
 611 rte_vhost_driver_session_start(void)
 612 {
 613         fdset_event_dispatch(&vhost_user.fdset);
 614         return 0;
 615 }