io/channel-socket.c

   1 /*
   2  * QEMU I/O channels sockets driver
   3  *
   4  * Copyright (c) 2015 Red Hat, Inc.
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "qemu/osdep.h"
  21 #include "qapi/error.h"
  22 #include "qapi/qapi-visit-sockets.h"
  23 #include "qemu/module.h"
  24 #include "io/channel-socket.h"
  25 #include "io/channel-watch.h"
  26 #include "trace.h"
  27 #include "qapi/clone-visitor.h"
  28 #ifdef CONFIG_LINUX
  29 #include <linux/errqueue.h>
  30 #include <sys/socket.h>
  31
  32 #if (defined(MSG_ZEROCOPY) && defined(SO_ZEROCOPY))
  33 #define QEMU_MSG_ZEROCOPY
  34 #endif
  35 #endif
  36
  37 #define SOCKET_MAX_FDS 16
  38
  39 SocketAddress *
  40 qio_channel_socket_get_local_address(QIOChannelSocket *ioc,
  41                                      Error **errp)
  42 {
  43     return socket_sockaddr_to_address(&ioc->localAddr,
  44                                       ioc->localAddrLen,
  45                                       errp);
  46 }
  47
  48 SocketAddress *
  49 qio_channel_socket_get_remote_address(QIOChannelSocket *ioc,
  50                                       Error **errp)
  51 {
  52     return socket_sockaddr_to_address(&ioc->remoteAddr,
  53                                       ioc->remoteAddrLen,
  54                                       errp);
  55 }
  56
  57 QIOChannelSocket *
  58 qio_channel_socket_new(void)
  59 {
  60     QIOChannelSocket *sioc;
  61     QIOChannel *ioc;
  62
  63     sioc = QIO_CHANNEL_SOCKET(object_new(TYPE_QIO_CHANNEL_SOCKET));
  64     sioc->fd = -1;
  65     sioc->zero_copy_queued = 0;
  66     sioc->zero_copy_sent = 0;
  67
  68     ioc = QIO_CHANNEL(sioc);
  69     qio_channel_set_feature(ioc, QIO_CHANNEL_FEATURE_SHUTDOWN);
  70
  71 #ifdef WIN32
  72     ioc->event = CreateEvent(NULL, FALSE, FALSE, NULL);
  73 #endif
  74
  75     trace_qio_channel_socket_new(sioc);
  76
  77     return sioc;
  78 }
  79
  80
  81 static int
  82 qio_channel_socket_set_fd(QIOChannelSocket *sioc,
  83                           int fd,
  84                           Error **errp)
  85 {
  86     if (sioc->fd != -1) {
  87         error_setg(errp, "Socket is already open");
  88         return -1;
  89     }
  90
  91     sioc->fd = fd;
  92     sioc->remoteAddrLen = sizeof(sioc->remoteAddr);
  93     sioc->localAddrLen = sizeof(sioc->localAddr);
  94
  95
  96     if (getpeername(fd, (struct sockaddr *)&sioc->remoteAddr,
  97                     &sioc->remoteAddrLen) < 0) {
  98         if (errno == ENOTCONN) {
  99             memset(&sioc->remoteAddr, 0, sizeof(sioc->remoteAddr));
 100             sioc->remoteAddrLen = sizeof(sioc->remoteAddr);
 101         } else {
 102             error_setg_errno(errp, errno,
 103                              "Unable to query remote socket address");
 104             goto error;
 105         }
 106     }
 107
 108     if (getsockname(fd, (struct sockaddr *)&sioc->localAddr,
 109                     &sioc->localAddrLen) < 0) {
 110         error_setg_errno(errp, errno,
 111                          "Unable to query local socket address");
 112         goto error;
 113     }
 114
 115 #ifndef WIN32
 116     if (sioc->localAddr.ss_family == AF_UNIX) {
 117         QIOChannel *ioc = QIO_CHANNEL(sioc);
 118         qio_channel_set_feature(ioc, QIO_CHANNEL_FEATURE_FD_PASS);
 119     }
 120 #endif /* WIN32 */
 121
 122     return 0;
 123
 124  error:
 125     sioc->fd = -1; /* Let the caller close FD on failure */
 126     return -1;
 127 }
 128
 129 QIOChannelSocket *
 130 qio_channel_socket_new_fd(int fd,
 131                           Error **errp)
 132 {
 133     QIOChannelSocket *ioc;
 134
 135     ioc = qio_channel_socket_new();
 136     if (qio_channel_socket_set_fd(ioc, fd, errp) < 0) {
 137         object_unref(OBJECT(ioc));
 138         return NULL;
 139     }
 140
 141     trace_qio_channel_socket_new_fd(ioc, fd);
 142
 143     return ioc;
 144 }
 145
 146
 147 int qio_channel_socket_connect_sync(QIOChannelSocket *ioc,
 148                                     SocketAddress *addr,
 149                                     Error **errp)
 150 {
 151     int fd;
 152
 153     trace_qio_channel_socket_connect_sync(ioc, addr);
 154     fd = socket_connect(addr, errp);
 155     if (fd < 0) {
 156         trace_qio_channel_socket_connect_fail(ioc);
 157         return -1;
 158     }
 159
 160     trace_qio_channel_socket_connect_complete(ioc, fd);
 161     if (qio_channel_socket_set_fd(ioc, fd, errp) < 0) {
 162         close(fd);
 163         return -1;
 164     }
 165
 166 #ifdef QEMU_MSG_ZEROCOPY
 167     int ret, v = 1;
 168     ret = setsockopt(fd, SOL_SOCKET, SO_ZEROCOPY, &v, sizeof(v));
 169     if (ret == 0) {
 170         /* Zero copy available on host */
 171         qio_channel_set_feature(QIO_CHANNEL(ioc),
 172                                 QIO_CHANNEL_FEATURE_WRITE_ZERO_COPY);
 173     }
 174 #endif
 175
 176     qio_channel_set_feature(QIO_CHANNEL(ioc),
 177                             QIO_CHANNEL_FEATURE_READ_MSG_PEEK);
 178
 179     return 0;
 180 }
 181
 182
 183 static void qio_channel_socket_connect_worker(QIOTask *task,
 184                                               gpointer opaque)
 185 {
 186     QIOChannelSocket *ioc = QIO_CHANNEL_SOCKET(qio_task_get_source(task));
 187     SocketAddress *addr = opaque;
 188     Error *err = NULL;
 189
 190     qio_channel_socket_connect_sync(ioc, addr, &err);
 191
 192     qio_task_set_error(task, err);
 193 }
 194
 195
 196 void qio_channel_socket_connect_async(QIOChannelSocket *ioc,
 197                                       SocketAddress *addr,
 198                                       QIOTaskFunc callback,
 199                                       gpointer opaque,
 200                                       GDestroyNotify destroy,
 201                                       GMainContext *context)
 202 {
 203     QIOTask *task = qio_task_new(
 204         OBJECT(ioc), callback, opaque, destroy);
 205     SocketAddress *addrCopy;
 206
 207     addrCopy = QAPI_CLONE(SocketAddress, addr);
 208
 209     /* socket_connect() does a non-blocking connect(), but it
 210      * still blocks in DNS lookups, so we must use a thread */
 211     trace_qio_channel_socket_connect_async(ioc, addr);
 212     qio_task_run_in_thread(task,
 213                            qio_channel_socket_connect_worker,
 214                            addrCopy,
 215                            (GDestroyNotify)qapi_free_SocketAddress,
 216                            context);
 217 }
 218
 219
 220 int qio_channel_socket_listen_sync(QIOChannelSocket *ioc,
 221                                    SocketAddress *addr,
 222                                    int num,
 223                                    Error **errp)
 224 {
 225     int fd;
 226
 227     trace_qio_channel_socket_listen_sync(ioc, addr, num);
 228     fd = socket_listen(addr, num, errp);
 229     if (fd < 0) {
 230         trace_qio_channel_socket_listen_fail(ioc);
 231         return -1;
 232     }
 233
 234     trace_qio_channel_socket_listen_complete(ioc, fd);
 235     if (qio_channel_socket_set_fd(ioc, fd, errp) < 0) {
 236         close(fd);
 237         return -1;
 238     }
 239     qio_channel_set_feature(QIO_CHANNEL(ioc), QIO_CHANNEL_FEATURE_LISTEN);
 240
 241     return 0;
 242 }
 243
 244
 245 struct QIOChannelListenWorkerData {
 246     SocketAddress *addr;
 247     int num; /* amount of expected connections */
 248 };
 249
 250 static void qio_channel_listen_worker_free(gpointer opaque)
 251 {
 252     struct QIOChannelListenWorkerData *data = opaque;
 253
 254     qapi_free_SocketAddress(data->addr);
 255     g_free(data);
 256 }
 257
 258 static void qio_channel_socket_listen_worker(QIOTask *task,
 259                                              gpointer opaque)
 260 {
 261     QIOChannelSocket *ioc = QIO_CHANNEL_SOCKET(qio_task_get_source(task));
 262     struct QIOChannelListenWorkerData *data = opaque;
 263     Error *err = NULL;
 264
 265     qio_channel_socket_listen_sync(ioc, data->addr, data->num, &err);
 266
 267     qio_task_set_error(task, err);
 268 }
 269
 270
 271 void qio_channel_socket_listen_async(QIOChannelSocket *ioc,
 272                                      SocketAddress *addr,
 273                                      int num,
 274                                      QIOTaskFunc callback,
 275                                      gpointer opaque,
 276                                      GDestroyNotify destroy,
 277                                      GMainContext *context)
 278 {
 279     QIOTask *task = qio_task_new(
 280         OBJECT(ioc), callback, opaque, destroy);
 281     struct QIOChannelListenWorkerData *data;
 282
 283     data = g_new0(struct QIOChannelListenWorkerData, 1);
 284     data->addr = QAPI_CLONE(SocketAddress, addr);
 285     data->num = num;
 286
 287     /* socket_listen() blocks in DNS lookups, so we must use a thread */
 288     trace_qio_channel_socket_listen_async(ioc, addr, num);
 289     qio_task_run_in_thread(task,
 290                            qio_channel_socket_listen_worker,
 291                            data,
 292                            qio_channel_listen_worker_free,
 293                            context);
 294 }
 295
 296
 297 int qio_channel_socket_dgram_sync(QIOChannelSocket *ioc,
 298                                   SocketAddress *localAddr,
 299                                   SocketAddress *remoteAddr,
 300                                   Error **errp)
 301 {
 302     int fd;
 303
 304     trace_qio_channel_socket_dgram_sync(ioc, localAddr, remoteAddr);
 305     fd = socket_dgram(remoteAddr, localAddr, errp);
 306     if (fd < 0) {
 307         trace_qio_channel_socket_dgram_fail(ioc);
 308         return -1;
 309     }
 310
 311     trace_qio_channel_socket_dgram_complete(ioc, fd);
 312     if (qio_channel_socket_set_fd(ioc, fd, errp) < 0) {
 313         close(fd);
 314         return -1;
 315     }
 316
 317     return 0;
 318 }
 319
 320
 321 struct QIOChannelSocketDGramWorkerData {
 322     SocketAddress *localAddr;
 323     SocketAddress *remoteAddr;
 324 };
 325
 326
 327 static void qio_channel_socket_dgram_worker_free(gpointer opaque)
 328 {
 329     struct QIOChannelSocketDGramWorkerData *data = opaque;
 330     qapi_free_SocketAddress(data->localAddr);
 331     qapi_free_SocketAddress(data->remoteAddr);
 332     g_free(data);
 333 }
 334
 335 static void qio_channel_socket_dgram_worker(QIOTask *task,
 336                                             gpointer opaque)
 337 {
 338     QIOChannelSocket *ioc = QIO_CHANNEL_SOCKET(qio_task_get_source(task));
 339     struct QIOChannelSocketDGramWorkerData *data = opaque;
 340     Error *err = NULL;
 341
 342     /* socket_dgram() blocks in DNS lookups, so we must use a thread */
 343     qio_channel_socket_dgram_sync(ioc, data->localAddr,
 344                                   data->remoteAddr, &err);
 345
 346     qio_task_set_error(task, err);
 347 }
 348
 349
 350 void qio_channel_socket_dgram_async(QIOChannelSocket *ioc,
 351                                     SocketAddress *localAddr,
 352                                     SocketAddress *remoteAddr,
 353                                     QIOTaskFunc callback,
 354                                     gpointer opaque,
 355                                     GDestroyNotify destroy,
 356                                     GMainContext *context)
 357 {
 358     QIOTask *task = qio_task_new(
 359         OBJECT(ioc), callback, opaque, destroy);
 360     struct QIOChannelSocketDGramWorkerData *data = g_new0(
 361         struct QIOChannelSocketDGramWorkerData, 1);
 362
 363     data->localAddr = QAPI_CLONE(SocketAddress, localAddr);
 364     data->remoteAddr = QAPI_CLONE(SocketAddress, remoteAddr);
 365
 366     trace_qio_channel_socket_dgram_async(ioc, localAddr, remoteAddr);
 367     qio_task_run_in_thread(task,
 368                            qio_channel_socket_dgram_worker,
 369                            data,
 370                            qio_channel_socket_dgram_worker_free,
 371                            context);
 372 }
 373
 374
 375 QIOChannelSocket *
 376 qio_channel_socket_accept(QIOChannelSocket *ioc,
 377                           Error **errp)
 378 {
 379     QIOChannelSocket *cioc;
 380
 381     cioc = qio_channel_socket_new();
 382     cioc->remoteAddrLen = sizeof(ioc->remoteAddr);
 383     cioc->localAddrLen = sizeof(ioc->localAddr);
 384
 385  retry:
 386     trace_qio_channel_socket_accept(ioc);
 387     cioc->fd = qemu_accept(ioc->fd, (struct sockaddr *)&cioc->remoteAddr,
 388                            &cioc->remoteAddrLen);
 389     if (cioc->fd < 0) {
 390         if (errno == EINTR) {
 391             goto retry;
 392         }
 393         error_setg_errno(errp, errno, "Unable to accept connection");
 394         trace_qio_channel_socket_accept_fail(ioc);
 395         goto error;
 396     }
 397
 398     if (getsockname(cioc->fd, (struct sockaddr *)&cioc->localAddr,
 399                     &cioc->localAddrLen) < 0) {
 400         error_setg_errno(errp, errno,
 401                          "Unable to query local socket address");
 402         goto error;
 403     }
 404
 405 #ifndef WIN32
 406     if (cioc->localAddr.ss_family == AF_UNIX) {
 407         QIOChannel *ioc_local = QIO_CHANNEL(cioc);
 408         qio_channel_set_feature(ioc_local, QIO_CHANNEL_FEATURE_FD_PASS);
 409     }
 410 #endif /* WIN32 */
 411
 412     qio_channel_set_feature(QIO_CHANNEL(cioc),
 413                             QIO_CHANNEL_FEATURE_READ_MSG_PEEK);
 414
 415     trace_qio_channel_socket_accept_complete(ioc, cioc, cioc->fd);
 416     return cioc;
 417
 418  error:
 419     object_unref(OBJECT(cioc));
 420     return NULL;
 421 }
 422
 423 static void qio_channel_socket_init(Object *obj)
 424 {
 425     QIOChannelSocket *ioc = QIO_CHANNEL_SOCKET(obj);
 426     ioc->fd = -1;
 427 }
 428
 429 static void qio_channel_socket_finalize(Object *obj)
 430 {
 431     QIOChannelSocket *ioc = QIO_CHANNEL_SOCKET(obj);
 432
 433     if (ioc->fd != -1) {
 434         QIOChannel *ioc_local = QIO_CHANNEL(ioc);
 435         if (qio_channel_has_feature(ioc_local, QIO_CHANNEL_FEATURE_LISTEN)) {
 436             Error *err = NULL;
 437
 438             socket_listen_cleanup(ioc->fd, &err);
 439             if (err) {
 440                 error_report_err(err);
 441                 err = NULL;
 442             }
 443         }
 444 #ifdef WIN32
 445         WSAEventSelect(ioc->fd, NULL, 0);
 446 #endif
 447         closesocket(ioc->fd);
 448         ioc->fd = -1;
 449     }
 450 }
 451
 452
 453 #ifndef WIN32
 454 static void qio_channel_socket_copy_fds(struct msghdr *msg,
 455                                         int **fds, size_t *nfds)
 456 {
 457     struct cmsghdr *cmsg;
 458
 459     *nfds = 0;
 460     *fds = NULL;
 461
 462     for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
 463         int fd_size, i;
 464         int gotfds;
 465
 466         if (cmsg->cmsg_len < CMSG_LEN(sizeof(int)) ||
 467             cmsg->cmsg_level != SOL_SOCKET ||
 468             cmsg->cmsg_type != SCM_RIGHTS) {
 469             continue;
 470         }
 471
 472         fd_size = cmsg->cmsg_len - CMSG_LEN(0);
 473
 474         if (!fd_size) {
 475             continue;
 476         }
 477
 478         gotfds = fd_size / sizeof(int);
 479         *fds = g_renew(int, *fds, *nfds + gotfds);
 480         memcpy(*fds + *nfds, CMSG_DATA(cmsg), fd_size);
 481
 482         for (i = 0; i < gotfds; i++) {
 483             int fd = (*fds)[*nfds + i];
 484             if (fd < 0) {
 485                 continue;
 486             }
 487
 488             /* O_NONBLOCK is preserved across SCM_RIGHTS so reset it */
 489             qemu_socket_set_block(fd);
 490
 491 #ifndef MSG_CMSG_CLOEXEC
 492             qemu_set_cloexec(fd);
 493 #endif
 494         }
 495         *nfds += gotfds;
 496     }
 497 }
 498
 499
 500 static ssize_t qio_channel_socket_readv(QIOChannel *ioc,
 501                                         const struct iovec *iov,
 502                                         size_t niov,
 503                                         int **fds,
 504                                         size_t *nfds,
 505                                         int flags,
 506                                         Error **errp)
 507 {
 508     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
 509     ssize_t ret;
 510     struct msghdr msg = { NULL, };
 511     char control[CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS)];
 512     int sflags = 0;
 513
 514     memset(control, 0, CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS));
 515
 516     msg.msg_iov = (struct iovec *)iov;
 517     msg.msg_iovlen = niov;
 518     if (fds && nfds) {
 519         msg.msg_control = control;
 520         msg.msg_controllen = sizeof(control);
 521 #ifdef MSG_CMSG_CLOEXEC
 522         sflags |= MSG_CMSG_CLOEXEC;
 523 #endif
 524
 525     }
 526
 527     if (flags & QIO_CHANNEL_READ_FLAG_MSG_PEEK) {
 528         sflags |= MSG_PEEK;
 529     }
 530
 531  retry:
 532     ret = recvmsg(sioc->fd, &msg, sflags);
 533     if (ret < 0) {
 534         if (errno == EAGAIN) {
 535             return QIO_CHANNEL_ERR_BLOCK;
 536         }
 537         if (errno == EINTR) {
 538             goto retry;
 539         }
 540
 541         error_setg_errno(errp, errno,
 542                          "Unable to read from socket");
 543         return -1;
 544     }
 545
 546     if (fds && nfds) {
 547         qio_channel_socket_copy_fds(&msg, fds, nfds);
 548     }
 549
 550     return ret;
 551 }
 552
 553 static ssize_t qio_channel_socket_writev(QIOChannel *ioc,
 554                                          const struct iovec *iov,
 555                                          size_t niov,
 556                                          int *fds,
 557                                          size_t nfds,
 558                                          int flags,
 559                                          Error **errp)
 560 {
 561     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
 562     ssize_t ret;
 563     struct msghdr msg = { NULL, };
 564     char control[CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS)];
 565     size_t fdsize = sizeof(int) * nfds;
 566     struct cmsghdr *cmsg;
 567     int sflags = 0;
 568
 569     memset(control, 0, CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS));
 570
 571     msg.msg_iov = (struct iovec *)iov;
 572     msg.msg_iovlen = niov;
 573
 574     if (nfds) {
 575         if (nfds > SOCKET_MAX_FDS) {
 576             error_setg_errno(errp, EINVAL,
 577                              "Only %d FDs can be sent, got %zu",
 578                              SOCKET_MAX_FDS, nfds);
 579             return -1;
 580         }
 581
 582         msg.msg_control = control;
 583         msg.msg_controllen = CMSG_SPACE(sizeof(int) * nfds);
 584
 585         cmsg = CMSG_FIRSTHDR(&msg);
 586         cmsg->cmsg_len = CMSG_LEN(fdsize);
 587         cmsg->cmsg_level = SOL_SOCKET;
 588         cmsg->cmsg_type = SCM_RIGHTS;
 589         memcpy(CMSG_DATA(cmsg), fds, fdsize);
 590     }
 591
 592     if (flags & QIO_CHANNEL_WRITE_FLAG_ZERO_COPY) {
 593 #ifdef QEMU_MSG_ZEROCOPY
 594         sflags = MSG_ZEROCOPY;
 595 #else
 596         /*
 597          * We expect QIOChannel class entry point to have
 598          * blocked this code path already
 599          */
 600         g_assert_not_reached();
 601 #endif
 602     }
 603
 604  retry:
 605     ret = sendmsg(sioc->fd, &msg, sflags);
 606     if (ret <= 0) {
 607         switch (errno) {
 608         case EAGAIN:
 609             return QIO_CHANNEL_ERR_BLOCK;
 610         case EINTR:
 611             goto retry;
 612         case ENOBUFS:
 613             if (flags & QIO_CHANNEL_WRITE_FLAG_ZERO_COPY) {
 614                 error_setg_errno(errp, errno,
 615                                  "Process can't lock enough memory for using MSG_ZEROCOPY");
 616                 return -1;
 617             }
 618             break;
 619         }
 620
 621         error_setg_errno(errp, errno,
 622                          "Unable to write to socket");
 623         return -1;
 624     }
 625
 626     if (flags & QIO_CHANNEL_WRITE_FLAG_ZERO_COPY) {
 627         sioc->zero_copy_queued++;
 628     }
 629
 630     return ret;
 631 }
 632 #else /* WIN32 */
 633 static ssize_t qio_channel_socket_readv(QIOChannel *ioc,
 634                                         const struct iovec *iov,
 635                                         size_t niov,
 636                                         int **fds,
 637                                         size_t *nfds,
 638                                         int flags,
 639                                         Error **errp)
 640 {
 641     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
 642     ssize_t done = 0;
 643     ssize_t i;
 644     int sflags = 0;
 645
 646     if (flags & QIO_CHANNEL_READ_FLAG_MSG_PEEK) {
 647         sflags |= MSG_PEEK;
 648     }
 649
 650     for (i = 0; i < niov; i++) {
 651         ssize_t ret;
 652     retry:
 653         ret = recv(sioc->fd,
 654                    iov[i].iov_base,
 655                    iov[i].iov_len,
 656                    sflags);
 657         if (ret < 0) {
 658             if (errno == EAGAIN) {
 659                 if (done) {
 660                     return done;
 661                 } else {
 662                     return QIO_CHANNEL_ERR_BLOCK;
 663                 }
 664             } else if (errno == EINTR) {
 665                 goto retry;
 666             } else {
 667                 error_setg_errno(errp, errno,
 668                                  "Unable to read from socket");
 669                 return -1;
 670             }
 671         }
 672         done += ret;
 673         if (ret < iov[i].iov_len) {
 674             return done;
 675         }
 676     }
 677
 678     return done;
 679 }
 680
 681 static ssize_t qio_channel_socket_writev(QIOChannel *ioc,
 682                                          const struct iovec *iov,
 683                                          size_t niov,
 684                                          int *fds,
 685                                          size_t nfds,
 686                                          int flags,
 687                                          Error **errp)
 688 {
 689     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
 690     ssize_t done = 0;
 691     ssize_t i;
 692
 693     for (i = 0; i < niov; i++) {
 694         ssize_t ret;
 695     retry:
 696         ret = send(sioc->fd,
 697                    iov[i].iov_base,
 698                    iov[i].iov_len,
 699                    0);
 700         if (ret < 0) {
 701             if (errno == EAGAIN) {
 702                 if (done) {
 703                     return done;
 704                 } else {
 705                     return QIO_CHANNEL_ERR_BLOCK;
 706                 }
 707             } else if (errno == EINTR) {
 708                 goto retry;
 709             } else {
 710                 error_setg_errno(errp, errno,
 711                                  "Unable to write to socket");
 712                 return -1;
 713             }
 714         }
 715         done += ret;
 716         if (ret < iov[i].iov_len) {
 717             return done;
 718         }
 719     }
 720
 721     return done;
 722 }
 723 #endif /* WIN32 */
 724
 725
 726 #ifdef QEMU_MSG_ZEROCOPY
 727 static int qio_channel_socket_flush(QIOChannel *ioc,
 728                                     Error **errp)
 729 {
 730     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
 731     struct msghdr msg = {};
 732     struct sock_extended_err *serr;
 733     struct cmsghdr *cm;
 734     char control[CMSG_SPACE(sizeof(*serr))];
 735     int received;
 736     int ret;
 737
 738     if (sioc->zero_copy_queued == sioc->zero_copy_sent) {
 739         return 0;
 740     }
 741
 742     msg.msg_control = control;
 743     msg.msg_controllen = sizeof(control);
 744     memset(control, 0, sizeof(control));
 745
 746     ret = 1;
 747
 748     while (sioc->zero_copy_sent < sioc->zero_copy_queued) {
 749         received = recvmsg(sioc->fd, &msg, MSG_ERRQUEUE);
 750         if (received < 0) {
 751             switch (errno) {
 752             case EAGAIN:
 753                 /* Nothing on errqueue, wait until something is available */
 754                 qio_channel_wait(ioc, G_IO_ERR);
 755                 continue;
 756             case EINTR:
 757                 continue;
 758             default:
 759                 error_setg_errno(errp, errno,
 760                                  "Unable to read errqueue");
 761                 return -1;
 762             }
 763         }
 764
 765         cm = CMSG_FIRSTHDR(&msg);
 766         if (cm->cmsg_level != SOL_IP   && cm->cmsg_type != IP_RECVERR &&
 767             cm->cmsg_level != SOL_IPV6 && cm->cmsg_type != IPV6_RECVERR) {
 768             error_setg_errno(errp, EPROTOTYPE,
 769                              "Wrong cmsg in errqueue");
 770             return -1;
 771         }
 772
 773         serr = (void *) CMSG_DATA(cm);
 774         if (serr->ee_errno != SO_EE_ORIGIN_NONE) {
 775             error_setg_errno(errp, serr->ee_errno,
 776                              "Error on socket");
 777             return -1;
 778         }
 779         if (serr->ee_origin != SO_EE_ORIGIN_ZEROCOPY) {
 780             error_setg_errno(errp, serr->ee_origin,
 781                              "Error not from zero copy");
 782             return -1;
 783         }
 784
 785         /* No errors, count successfully finished sendmsg()*/
 786         sioc->zero_copy_sent += serr->ee_data - serr->ee_info + 1;
 787
 788         /* If any sendmsg() succeeded using zero copy, return 0 at the end */
 789         if (serr->ee_code != SO_EE_CODE_ZEROCOPY_COPIED) {
 790             ret = 0;
 791         }
 792     }
 793
 794     return ret;
 795 }
 796
 797 #endif /* QEMU_MSG_ZEROCOPY */
 798
 799 static int
 800 qio_channel_socket_set_blocking(QIOChannel *ioc,
 801                                 bool enabled,
 802                                 Error **errp)
 803 {
 804     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
 805
 806     if (enabled) {
 807         qemu_socket_set_block(sioc->fd);
 808     } else {
 809         qemu_socket_set_nonblock(sioc->fd);
 810     }
 811     return 0;
 812 }
 813
 814
 815 static void
 816 qio_channel_socket_set_delay(QIOChannel *ioc,
 817                              bool enabled)
 818 {
 819     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
 820     int v = enabled ? 0 : 1;
 821
 822     setsockopt(sioc->fd,
 823                IPPROTO_TCP, TCP_NODELAY,
 824                &v, sizeof(v));
 825 }
 826
 827
 828 static void
 829 qio_channel_socket_set_cork(QIOChannel *ioc,
 830                             bool enabled)
 831 {
 832     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
 833     int v = enabled ? 1 : 0;
 834
 835     socket_set_cork(sioc->fd, v);
 836 }
 837
 838
 839 static int
 840 qio_channel_socket_close(QIOChannel *ioc,
 841                          Error **errp)
 842 {
 843     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
 844     int rc = 0;
 845     Error *err = NULL;
 846
 847     if (sioc->fd != -1) {
 848 #ifdef WIN32
 849         WSAEventSelect(sioc->fd, NULL, 0);
 850 #endif
 851         if (qio_channel_has_feature(ioc, QIO_CHANNEL_FEATURE_LISTEN)) {
 852             socket_listen_cleanup(sioc->fd, errp);
 853         }
 854
 855         if (closesocket(sioc->fd) < 0) {
 856             sioc->fd = -1;
 857             error_setg_errno(&err, errno, "Unable to close socket");
 858             error_propagate(errp, err);
 859             return -1;
 860         }
 861         sioc->fd = -1;
 862     }
 863     return rc;
 864 }
 865
 866 static int
 867 qio_channel_socket_shutdown(QIOChannel *ioc,
 868                             QIOChannelShutdown how,
 869                             Error **errp)
 870 {
 871     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
 872     int sockhow;
 873
 874     switch (how) {
 875     case QIO_CHANNEL_SHUTDOWN_READ:
 876         sockhow = SHUT_RD;
 877         break;
 878     case QIO_CHANNEL_SHUTDOWN_WRITE:
 879         sockhow = SHUT_WR;
 880         break;
 881     case QIO_CHANNEL_SHUTDOWN_BOTH:
 882     default:
 883         sockhow = SHUT_RDWR;
 884         break;
 885     }
 886
 887     if (shutdown(sioc->fd, sockhow) < 0) {
 888         error_setg_errno(errp, errno,
 889                          "Unable to shutdown socket");
 890         return -1;
 891     }
 892     return 0;
 893 }
 894
 895 static void qio_channel_socket_set_aio_fd_handler(QIOChannel *ioc,
 896                                                   AioContext *ctx,
 897                                                   IOHandler *io_read,
 898                                                   IOHandler *io_write,
 899                                                   void *opaque)
 900 {
 901     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
 902     aio_set_fd_handler(ctx, sioc->fd, false,
 903                        io_read, io_write, NULL, NULL, opaque);
 904 }
 905
 906 static GSource *qio_channel_socket_create_watch(QIOChannel *ioc,
 907                                                 GIOCondition condition)
 908 {
 909     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
 910     return qio_channel_create_socket_watch(ioc,
 911                                            sioc->fd,
 912                                            condition);
 913 }
 914
 915 static void qio_channel_socket_class_init(ObjectClass *klass,
 916                                           void *class_data G_GNUC_UNUSED)
 917 {
 918     QIOChannelClass *ioc_klass = QIO_CHANNEL_CLASS(klass);
 919
 920     ioc_klass->io_writev = qio_channel_socket_writev;
 921     ioc_klass->io_readv = qio_channel_socket_readv;
 922     ioc_klass->io_set_blocking = qio_channel_socket_set_blocking;
 923     ioc_klass->io_close = qio_channel_socket_close;
 924     ioc_klass->io_shutdown = qio_channel_socket_shutdown;
 925     ioc_klass->io_set_cork = qio_channel_socket_set_cork;
 926     ioc_klass->io_set_delay = qio_channel_socket_set_delay;
 927     ioc_klass->io_create_watch = qio_channel_socket_create_watch;
 928     ioc_klass->io_set_aio_fd_handler = qio_channel_socket_set_aio_fd_handler;
 929 #ifdef QEMU_MSG_ZEROCOPY
 930     ioc_klass->io_flush = qio_channel_socket_flush;
 931 #endif
 932 }
 933
 934 static const TypeInfo qio_channel_socket_info = {
 935     .parent = TYPE_QIO_CHANNEL,
 936     .name = TYPE_QIO_CHANNEL_SOCKET,
 937     .instance_size = sizeof(QIOChannelSocket),
 938     .instance_init = qio_channel_socket_init,
 939     .instance_finalize = qio_channel_socket_finalize,
 940     .class_init = qio_channel_socket_class_init,
 941 };
 942
 943 static void qio_channel_socket_register_types(void)
 944 {
 945     type_register_static(&qio_channel_socket_info);
 946 }
 947
 948 type_init(qio_channel_socket_register_types);