drivers/net/virtio/virtio_user/virtio_user_dev.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 <fcntl.h>
   8 #include <string.h>
   9 #include <errno.h>
  10 #include <sys/mman.h>
  11 #include <unistd.h>
  12 #include <sys/eventfd.h>
  13 #include <sys/types.h>
  14 #include <sys/stat.h>
  15
  16 #include <rte_eal_memconfig.h>
  17
  18 #include "vhost.h"
  19 #include "virtio_user_dev.h"
  20 #include "../virtio_ethdev.h"
  21
  22 #define VIRTIO_USER_MEM_EVENT_CLB_NAME "virtio_user_mem_event_clb"
  23
  24 static int
  25 virtio_user_create_queue(struct virtio_user_dev *dev, uint32_t queue_sel)
  26 {
  27         /* Of all per virtqueue MSGs, make sure VHOST_SET_VRING_CALL come
  28          * firstly because vhost depends on this msg to allocate virtqueue
  29          * pair.
  30          */
  31         struct vhost_vring_file file;
  32
  33         file.index = queue_sel;
  34         file.fd = dev->callfds[queue_sel];
  35         dev->ops->send_request(dev, VHOST_USER_SET_VRING_CALL, &file);
  36
  37         return 0;
  38 }
  39
  40 static int
  41 virtio_user_kick_queue(struct virtio_user_dev *dev, uint32_t queue_sel)
  42 {
  43         struct vhost_vring_file file;
  44         struct vhost_vring_state state;
  45         struct vring *vring = &dev->vrings[queue_sel];
  46         struct vring_packed *pq_vring = &dev->packed_vrings[queue_sel];
  47         struct vhost_vring_addr addr = {
  48                 .index = queue_sel,
  49                 .log_guest_addr = 0,
  50                 .flags = 0, /* disable log */
  51         };
  52
  53         if (dev->features & (1ULL << VIRTIO_F_RING_PACKED)) {
  54                 addr.desc_user_addr =
  55                         (uint64_t)(uintptr_t)pq_vring->desc;
  56                 addr.avail_user_addr =
  57                         (uint64_t)(uintptr_t)pq_vring->driver;
  58                 addr.used_user_addr =
  59                         (uint64_t)(uintptr_t)pq_vring->device;
  60         } else {
  61                 addr.desc_user_addr = (uint64_t)(uintptr_t)vring->desc;
  62                 addr.avail_user_addr = (uint64_t)(uintptr_t)vring->avail;
  63                 addr.used_user_addr = (uint64_t)(uintptr_t)vring->used;
  64         }
  65
  66         state.index = queue_sel;
  67         state.num = vring->num;
  68         dev->ops->send_request(dev, VHOST_USER_SET_VRING_NUM, &state);
  69
  70         state.index = queue_sel;
  71         state.num = 0; /* no reservation */
  72         if (dev->features & (1ULL << VIRTIO_F_RING_PACKED))
  73                 state.num |= (1 << 15);
  74         dev->ops->send_request(dev, VHOST_USER_SET_VRING_BASE, &state);
  75
  76         dev->ops->send_request(dev, VHOST_USER_SET_VRING_ADDR, &addr);
  77
  78         /* Of all per virtqueue MSGs, make sure VHOST_USER_SET_VRING_KICK comes
  79          * lastly because vhost depends on this msg to judge if
  80          * virtio is ready.
  81          */
  82         file.index = queue_sel;
  83         file.fd = dev->kickfds[queue_sel];
  84         dev->ops->send_request(dev, VHOST_USER_SET_VRING_KICK, &file);
  85
  86         return 0;
  87 }
  88
  89 static int
  90 virtio_user_queue_setup(struct virtio_user_dev *dev,
  91                         int (*fn)(struct virtio_user_dev *, uint32_t))
  92 {
  93         uint32_t i, queue_sel;
  94
  95         for (i = 0; i < dev->max_queue_pairs; ++i) {
  96                 queue_sel = 2 * i + VTNET_SQ_RQ_QUEUE_IDX;
  97                 if (fn(dev, queue_sel) < 0) {
  98                         PMD_DRV_LOG(INFO, "setup rx vq fails: %u", i);
  99                         return -1;
 100                 }
 101         }
 102         for (i = 0; i < dev->max_queue_pairs; ++i) {
 103                 queue_sel = 2 * i + VTNET_SQ_TQ_QUEUE_IDX;
 104                 if (fn(dev, queue_sel) < 0) {
 105                         PMD_DRV_LOG(INFO, "setup tx vq fails: %u", i);
 106                         return -1;
 107                 }
 108         }
 109
 110         return 0;
 111 }
 112
 113 int
 114 is_vhost_user_by_type(const char *path)
 115 {
 116         struct stat sb;
 117
 118         if (stat(path, &sb) == -1)
 119                 return 0;
 120
 121         return S_ISSOCK(sb.st_mode);
 122 }
 123
 124 int
 125 virtio_user_start_device(struct virtio_user_dev *dev)
 126 {
 127         struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config;
 128         uint64_t features;
 129         int ret;
 130
 131         /*
 132          * XXX workaround!
 133          *
 134          * We need to make sure that the locks will be
 135          * taken in the correct order to avoid deadlocks.
 136          *
 137          * Before releasing this lock, this thread should
 138          * not trigger any memory hotplug events.
 139          *
 140          * This is a temporary workaround, and should be
 141          * replaced when we get proper supports from the
 142          * memory subsystem in the future.
 143          */
 144         rte_rwlock_read_lock(&mcfg->memory_hotplug_lock);
 145         pthread_mutex_lock(&dev->mutex);
 146
 147         if (is_vhost_user_by_type(dev->path) && dev->vhostfd < 0)
 148                 goto error;
 149
 150         /* Step 0: tell vhost to create queues */
 151         if (virtio_user_queue_setup(dev, virtio_user_create_queue) < 0)
 152                 goto error;
 153
 154         /* Step 1: set features */
 155         features = dev->features;
 156         /* Strip VIRTIO_NET_F_MAC, as MAC address is handled in vdev init */
 157         features &= ~(1ull << VIRTIO_NET_F_MAC);
 158         /* Strip VIRTIO_NET_F_CTRL_VQ, as devices do not really need to know */
 159         features &= ~(1ull << VIRTIO_NET_F_CTRL_VQ);
 160         features &= ~(1ull << VIRTIO_NET_F_STATUS);
 161         ret = dev->ops->send_request(dev, VHOST_USER_SET_FEATURES, &features);
 162         if (ret < 0)
 163                 goto error;
 164         PMD_DRV_LOG(INFO, "set features: %" PRIx64, features);
 165
 166         /* Step 2: share memory regions */
 167         ret = dev->ops->send_request(dev, VHOST_USER_SET_MEM_TABLE, NULL);
 168         if (ret < 0)
 169                 goto error;
 170
 171         /* Step 3: kick queues */
 172         if (virtio_user_queue_setup(dev, virtio_user_kick_queue) < 0)
 173                 goto error;
 174
 175         /* Step 4: enable queues
 176          * we enable the 1st queue pair by default.
 177          */
 178         dev->ops->enable_qp(dev, 0, 1);
 179
 180         dev->started = true;
 181         pthread_mutex_unlock(&dev->mutex);
 182         rte_rwlock_read_unlock(&mcfg->memory_hotplug_lock);
 183
 184         return 0;
 185 error:
 186         pthread_mutex_unlock(&dev->mutex);
 187         rte_rwlock_read_unlock(&mcfg->memory_hotplug_lock);
 188         /* TODO: free resource here or caller to check */
 189         return -1;
 190 }
 191
 192 int virtio_user_stop_device(struct virtio_user_dev *dev)
 193 {
 194         struct vhost_vring_state state;
 195         uint32_t i;
 196         int error = 0;
 197
 198         pthread_mutex_lock(&dev->mutex);
 199         if (!dev->started)
 200                 goto out;
 201
 202         for (i = 0; i < dev->max_queue_pairs; ++i)
 203                 dev->ops->enable_qp(dev, i, 0);
 204
 205         /* Stop the backend. */
 206         for (i = 0; i < dev->max_queue_pairs * 2; ++i) {
 207                 state.index = i;
 208                 if (dev->ops->send_request(dev, VHOST_USER_GET_VRING_BASE,
 209                                            &state) < 0) {
 210                         PMD_DRV_LOG(ERR, "get_vring_base failed, index=%u\n",
 211                                     i);
 212                         error = -1;
 213                         goto out;
 214                 }
 215         }
 216
 217         dev->started = false;
 218 out:
 219         pthread_mutex_unlock(&dev->mutex);
 220
 221         return error;
 222 }
 223
 224 static inline void
 225 parse_mac(struct virtio_user_dev *dev, const char *mac)
 226 {
 227         int i, r;
 228         uint32_t tmp[ETHER_ADDR_LEN];
 229
 230         if (!mac)
 231                 return;
 232
 233         r = sscanf(mac, "%x:%x:%x:%x:%x:%x", &tmp[0],
 234                         &tmp[1], &tmp[2], &tmp[3], &tmp[4], &tmp[5]);
 235         if (r == ETHER_ADDR_LEN) {
 236                 for (i = 0; i < ETHER_ADDR_LEN; ++i)
 237                         dev->mac_addr[i] = (uint8_t)tmp[i];
 238                 dev->mac_specified = 1;
 239         } else {
 240                 /* ignore the wrong mac, use random mac */
 241                 PMD_DRV_LOG(ERR, "wrong format of mac: %s", mac);
 242         }
 243 }
 244
 245 static int
 246 virtio_user_dev_init_notify(struct virtio_user_dev *dev)
 247 {
 248         uint32_t i, j;
 249         int callfd;
 250         int kickfd;
 251
 252         for (i = 0; i < VIRTIO_MAX_VIRTQUEUES; ++i) {
 253                 if (i >= dev->max_queue_pairs * 2) {
 254                         dev->kickfds[i] = -1;
 255                         dev->callfds[i] = -1;
 256                         continue;
 257                 }
 258
 259                 /* May use invalid flag, but some backend uses kickfd and
 260                  * callfd as criteria to judge if dev is alive. so finally we
 261                  * use real event_fd.
 262                  */
 263                 callfd = eventfd(0, EFD_CLOEXEC | EFD_NONBLOCK);
 264                 if (callfd < 0) {
 265                         PMD_DRV_LOG(ERR, "callfd error, %s", strerror(errno));
 266                         break;
 267                 }
 268                 kickfd = eventfd(0, EFD_CLOEXEC | EFD_NONBLOCK);
 269                 if (kickfd < 0) {
 270                         PMD_DRV_LOG(ERR, "kickfd error, %s", strerror(errno));
 271                         break;
 272                 }
 273                 dev->callfds[i] = callfd;
 274                 dev->kickfds[i] = kickfd;
 275         }
 276
 277         if (i < VIRTIO_MAX_VIRTQUEUES) {
 278                 for (j = 0; j <= i; ++j) {
 279                         close(dev->callfds[j]);
 280                         close(dev->kickfds[j]);
 281                 }
 282
 283                 return -1;
 284         }
 285
 286         return 0;
 287 }
 288
 289 static int
 290 virtio_user_fill_intr_handle(struct virtio_user_dev *dev)
 291 {
 292         uint32_t i;
 293         struct rte_eth_dev *eth_dev = &rte_eth_devices[dev->port_id];
 294
 295         if (!eth_dev->intr_handle) {
 296                 eth_dev->intr_handle = malloc(sizeof(*eth_dev->intr_handle));
 297                 if (!eth_dev->intr_handle) {
 298                         PMD_DRV_LOG(ERR, "fail to allocate intr_handle");
 299                         return -1;
 300                 }
 301                 memset(eth_dev->intr_handle, 0, sizeof(*eth_dev->intr_handle));
 302         }
 303
 304         for (i = 0; i < dev->max_queue_pairs; ++i)
 305                 eth_dev->intr_handle->efds[i] = dev->callfds[i];
 306         eth_dev->intr_handle->nb_efd = dev->max_queue_pairs;
 307         eth_dev->intr_handle->max_intr = dev->max_queue_pairs + 1;
 308         eth_dev->intr_handle->type = RTE_INTR_HANDLE_VDEV;
 309         /* For virtio vdev, no need to read counter for clean */
 310         eth_dev->intr_handle->efd_counter_size = 0;
 311         eth_dev->intr_handle->fd = -1;
 312         if (dev->vhostfd >= 0)
 313                 eth_dev->intr_handle->fd = dev->vhostfd;
 314         else if (dev->is_server)
 315                 eth_dev->intr_handle->fd = dev->listenfd;
 316
 317         return 0;
 318 }
 319
 320 static void
 321 virtio_user_mem_event_cb(enum rte_mem_event type __rte_unused,
 322                                                  const void *addr __rte_unused,
 323                                                  size_t len __rte_unused,
 324                                                  void *arg)
 325 {
 326         struct virtio_user_dev *dev = arg;
 327         struct rte_memseg_list *msl;
 328         uint16_t i;
 329
 330         /* ignore externally allocated memory */
 331         msl = rte_mem_virt2memseg_list(addr);
 332         if (msl->external)
 333                 return;
 334
 335         pthread_mutex_lock(&dev->mutex);
 336
 337         if (dev->started == false)
 338                 goto exit;
 339
 340         /* Step 1: pause the active queues */
 341         for (i = 0; i < dev->queue_pairs; i++)
 342                 dev->ops->enable_qp(dev, i, 0);
 343
 344         /* Step 2: update memory regions */
 345         dev->ops->send_request(dev, VHOST_USER_SET_MEM_TABLE, NULL);
 346
 347         /* Step 3: resume the active queues */
 348         for (i = 0; i < dev->queue_pairs; i++)
 349                 dev->ops->enable_qp(dev, i, 1);
 350
 351 exit:
 352         pthread_mutex_unlock(&dev->mutex);
 353 }
 354
 355 static int
 356 virtio_user_dev_setup(struct virtio_user_dev *dev)
 357 {
 358         uint32_t q;
 359
 360         dev->vhostfd = -1;
 361         dev->vhostfds = NULL;
 362         dev->tapfds = NULL;
 363
 364         if (dev->is_server) {
 365                 if (access(dev->path, F_OK) == 0 &&
 366                     !is_vhost_user_by_type(dev->path)) {
 367                         PMD_DRV_LOG(ERR, "Server mode doesn't support vhost-kernel!");
 368                         return -1;
 369                 }
 370                 dev->ops = &virtio_ops_user;
 371         } else {
 372                 if (is_vhost_user_by_type(dev->path)) {
 373                         dev->ops = &virtio_ops_user;
 374                 } else {
 375                         dev->ops = &virtio_ops_kernel;
 376
 377                         dev->vhostfds = malloc(dev->max_queue_pairs *
 378                                                sizeof(int));
 379                         dev->tapfds = malloc(dev->max_queue_pairs *
 380                                              sizeof(int));
 381                         if (!dev->vhostfds || !dev->tapfds) {
 382                                 PMD_INIT_LOG(ERR, "Failed to malloc");
 383                                 return -1;
 384                         }
 385
 386                         for (q = 0; q < dev->max_queue_pairs; ++q) {
 387                                 dev->vhostfds[q] = -1;
 388                                 dev->tapfds[q] = -1;
 389                         }
 390                 }
 391         }
 392
 393         if (dev->ops->setup(dev) < 0)
 394                 return -1;
 395
 396         if (virtio_user_dev_init_notify(dev) < 0)
 397                 return -1;
 398
 399         if (virtio_user_fill_intr_handle(dev) < 0)
 400                 return -1;
 401
 402         return 0;
 403 }
 404
 405 /* Use below macro to filter features from vhost backend */
 406 #define VIRTIO_USER_SUPPORTED_FEATURES                  \
 407         (1ULL << VIRTIO_NET_F_MAC               |       \
 408          1ULL << VIRTIO_NET_F_STATUS            |       \
 409          1ULL << VIRTIO_NET_F_MQ                |       \
 410          1ULL << VIRTIO_NET_F_CTRL_MAC_ADDR     |       \
 411          1ULL << VIRTIO_NET_F_CTRL_VQ           |       \
 412          1ULL << VIRTIO_NET_F_CTRL_RX           |       \
 413          1ULL << VIRTIO_NET_F_CTRL_VLAN         |       \
 414          1ULL << VIRTIO_NET_F_CSUM              |       \
 415          1ULL << VIRTIO_NET_F_HOST_TSO4         |       \
 416          1ULL << VIRTIO_NET_F_HOST_TSO6         |       \
 417          1ULL << VIRTIO_NET_F_MRG_RXBUF         |       \
 418          1ULL << VIRTIO_RING_F_INDIRECT_DESC    |       \
 419          1ULL << VIRTIO_NET_F_GUEST_CSUM        |       \
 420          1ULL << VIRTIO_NET_F_GUEST_TSO4        |       \
 421          1ULL << VIRTIO_NET_F_GUEST_TSO6        |       \
 422          1ULL << VIRTIO_F_IN_ORDER              |       \
 423          1ULL << VIRTIO_F_VERSION_1             |       \
 424          1ULL << VIRTIO_F_RING_PACKED)
 425
 426 int
 427 virtio_user_dev_init(struct virtio_user_dev *dev, char *path, int queues,
 428                      int cq, int queue_size, const char *mac, char **ifname,
 429                      int server, int mrg_rxbuf, int in_order, int packed_vq)
 430 {
 431         pthread_mutex_init(&dev->mutex, NULL);
 432         snprintf(dev->path, PATH_MAX, "%s", path);
 433         dev->started = 0;
 434         dev->max_queue_pairs = queues;
 435         dev->queue_pairs = 1; /* mq disabled by default */
 436         dev->queue_size = queue_size;
 437         dev->is_server = server;
 438         dev->mac_specified = 0;
 439         dev->frontend_features = 0;
 440         dev->unsupported_features = ~VIRTIO_USER_SUPPORTED_FEATURES;
 441         parse_mac(dev, mac);
 442
 443         if (*ifname) {
 444                 dev->ifname = *ifname;
 445                 *ifname = NULL;
 446         }
 447
 448         if (virtio_user_dev_setup(dev) < 0) {
 449                 PMD_INIT_LOG(ERR, "backend set up fails");
 450                 return -1;
 451         }
 452
 453         if (!dev->is_server) {
 454                 if (dev->ops->send_request(dev, VHOST_USER_SET_OWNER,
 455                                            NULL) < 0) {
 456                         PMD_INIT_LOG(ERR, "set_owner fails: %s",
 457                                      strerror(errno));
 458                         return -1;
 459                 }
 460
 461                 if (dev->ops->send_request(dev, VHOST_USER_GET_FEATURES,
 462                                            &dev->device_features) < 0) {
 463                         PMD_INIT_LOG(ERR, "get_features failed: %s",
 464                                      strerror(errno));
 465                         return -1;
 466                 }
 467         } else {
 468                 /* We just pretend vhost-user can support all these features.
 469                  * Note that this could be problematic that if some feature is
 470                  * negotiated but not supported by the vhost-user which comes
 471                  * later.
 472                  */
 473                 dev->device_features = VIRTIO_USER_SUPPORTED_FEATURES;
 474         }
 475
 476         if (!mrg_rxbuf)
 477                 dev->unsupported_features |= (1ull << VIRTIO_NET_F_MRG_RXBUF);
 478
 479         if (!in_order)
 480                 dev->unsupported_features |= (1ull << VIRTIO_F_IN_ORDER);
 481
 482         if (!packed_vq)
 483                 dev->unsupported_features |= (1ull << VIRTIO_F_RING_PACKED);
 484
 485         if (dev->mac_specified)
 486                 dev->frontend_features |= (1ull << VIRTIO_NET_F_MAC);
 487         else
 488                 dev->unsupported_features |= (1ull << VIRTIO_NET_F_MAC);
 489
 490         if (cq) {
 491                 /* device does not really need to know anything about CQ,
 492                  * so if necessary, we just claim to support CQ
 493                  */
 494                 dev->frontend_features |= (1ull << VIRTIO_NET_F_CTRL_VQ);
 495         } else {
 496                 dev->unsupported_features |= (1ull << VIRTIO_NET_F_CTRL_VQ);
 497                 /* Also disable features that depend on VIRTIO_NET_F_CTRL_VQ */
 498                 dev->unsupported_features |= (1ull << VIRTIO_NET_F_CTRL_RX);
 499                 dev->unsupported_features |= (1ull << VIRTIO_NET_F_CTRL_VLAN);
 500                 dev->unsupported_features |=
 501                         (1ull << VIRTIO_NET_F_GUEST_ANNOUNCE);
 502                 dev->unsupported_features |= (1ull << VIRTIO_NET_F_MQ);
 503                 dev->unsupported_features |=
 504                         (1ull << VIRTIO_NET_F_CTRL_MAC_ADDR);
 505         }
 506
 507         /* The backend will not report this feature, we add it explicitly */
 508         if (is_vhost_user_by_type(dev->path))
 509                 dev->frontend_features |= (1ull << VIRTIO_NET_F_STATUS);
 510
 511         /*
 512          * Device features =
 513          *     (frontend_features | backend_features) & ~unsupported_features;
 514          */
 515         dev->device_features |= dev->frontend_features;
 516         dev->device_features &= ~dev->unsupported_features;
 517
 518         if (rte_mem_event_callback_register(VIRTIO_USER_MEM_EVENT_CLB_NAME,
 519                                 virtio_user_mem_event_cb, dev)) {
 520                 if (rte_errno != ENOTSUP) {
 521                         PMD_INIT_LOG(ERR, "Failed to register mem event"
 522                                         " callback\n");
 523                         return -1;
 524                 }
 525         }
 526
 527         return 0;
 528 }
 529
 530 void
 531 virtio_user_dev_uninit(struct virtio_user_dev *dev)
 532 {
 533         uint32_t i;
 534
 535         virtio_user_stop_device(dev);
 536
 537         rte_mem_event_callback_unregister(VIRTIO_USER_MEM_EVENT_CLB_NAME, dev);
 538
 539         for (i = 0; i < dev->max_queue_pairs * 2; ++i) {
 540                 close(dev->callfds[i]);
 541                 close(dev->kickfds[i]);
 542         }
 543
 544         close(dev->vhostfd);
 545
 546         if (dev->is_server && dev->listenfd >= 0) {
 547                 close(dev->listenfd);
 548                 dev->listenfd = -1;
 549         }
 550
 551         if (dev->vhostfds) {
 552                 for (i = 0; i < dev->max_queue_pairs; ++i)
 553                         close(dev->vhostfds[i]);
 554                 free(dev->vhostfds);
 555                 free(dev->tapfds);
 556         }
 557
 558         free(dev->ifname);
 559
 560         if (dev->is_server)
 561                 unlink(dev->path);
 562 }
 563
 564 uint8_t
 565 virtio_user_handle_mq(struct virtio_user_dev *dev, uint16_t q_pairs)
 566 {
 567         uint16_t i;
 568         uint8_t ret = 0;
 569
 570         if (q_pairs > dev->max_queue_pairs) {
 571                 PMD_INIT_LOG(ERR, "multi-q config %u, but only %u supported",
 572                              q_pairs, dev->max_queue_pairs);
 573                 return -1;
 574         }
 575
 576         /* Server mode can't enable queue pairs if vhostfd is invalid,
 577          * always return 0 in this case.
 578          */
 579         if (!dev->is_server || dev->vhostfd >= 0) {
 580                 for (i = 0; i < q_pairs; ++i)
 581                         ret |= dev->ops->enable_qp(dev, i, 1);
 582                 for (i = q_pairs; i < dev->max_queue_pairs; ++i)
 583                         ret |= dev->ops->enable_qp(dev, i, 0);
 584         }
 585         dev->queue_pairs = q_pairs;
 586
 587         return ret;
 588 }
 589
 590 static uint32_t
 591 virtio_user_handle_ctrl_msg(struct virtio_user_dev *dev, struct vring *vring,
 592                             uint16_t idx_hdr)
 593 {
 594         struct virtio_net_ctrl_hdr *hdr;
 595         virtio_net_ctrl_ack status = ~0;
 596         uint16_t i, idx_data, idx_status;
 597         uint32_t n_descs = 0;
 598
 599         /* locate desc for header, data, and status */
 600         idx_data = vring->desc[idx_hdr].next;
 601         n_descs++;
 602
 603         i = idx_data;
 604         while (vring->desc[i].flags == VRING_DESC_F_NEXT) {
 605                 i = vring->desc[i].next;
 606                 n_descs++;
 607         }
 608
 609         /* locate desc for status */
 610         idx_status = i;
 611         n_descs++;
 612
 613         hdr = (void *)(uintptr_t)vring->desc[idx_hdr].addr;
 614         if (hdr->class == VIRTIO_NET_CTRL_MQ &&
 615             hdr->cmd == VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET) {
 616                 uint16_t queues;
 617
 618                 queues = *(uint16_t *)(uintptr_t)vring->desc[idx_data].addr;
 619                 status = virtio_user_handle_mq(dev, queues);
 620         }
 621
 622         /* Update status */
 623         *(virtio_net_ctrl_ack *)(uintptr_t)vring->desc[idx_status].addr = status;
 624
 625         return n_descs;
 626 }
 627
 628 static inline int
 629 desc_is_avail(struct vring_packed_desc *desc, bool wrap_counter)
 630 {
 631         return wrap_counter == !!(desc->flags & VRING_DESC_F_AVAIL(1)) &&
 632                 wrap_counter != !!(desc->flags & VRING_DESC_F_USED(1));
 633 }
 634
 635 static uint32_t
 636 virtio_user_handle_ctrl_msg_packed(struct virtio_user_dev *dev,
 637                                    struct vring_packed *vring,
 638                                    uint16_t idx_hdr)
 639 {
 640         struct virtio_net_ctrl_hdr *hdr;
 641         virtio_net_ctrl_ack status = ~0;
 642         uint16_t idx_data, idx_status;
 643         /* initialize to one, header is first */
 644         uint32_t n_descs = 1;
 645
 646         /* locate desc for header, data, and status */
 647         idx_data = idx_hdr + 1;
 648         if (idx_data >= dev->queue_size)
 649                 idx_data -= dev->queue_size;
 650
 651         n_descs++;
 652
 653         idx_status = idx_data;
 654         while (vring->desc[idx_status].flags & VRING_DESC_F_NEXT) {
 655                 idx_status++;
 656                 if (idx_status >= dev->queue_size)
 657                         idx_status -= dev->queue_size;
 658                 n_descs++;
 659         }
 660
 661         hdr = (void *)(uintptr_t)vring->desc[idx_hdr].addr;
 662         if (hdr->class == VIRTIO_NET_CTRL_MQ &&
 663             hdr->cmd == VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET) {
 664                 uint16_t queues;
 665
 666                 queues = *(uint16_t *)(uintptr_t)
 667                                 vring->desc[idx_data].addr;
 668                 status = virtio_user_handle_mq(dev, queues);
 669         }
 670
 671         /* Update status */
 672         *(virtio_net_ctrl_ack *)(uintptr_t)
 673                 vring->desc[idx_status].addr = status;
 674
 675         /* Update used descriptor */
 676         vring->desc[idx_hdr].id = vring->desc[idx_status].id;
 677         vring->desc[idx_hdr].len = sizeof(status);
 678
 679         return n_descs;
 680 }
 681
 682 void
 683 virtio_user_handle_cq_packed(struct virtio_user_dev *dev, uint16_t queue_idx)
 684 {
 685         struct virtio_user_queue *vq = &dev->packed_queues[queue_idx];
 686         struct vring_packed *vring = &dev->packed_vrings[queue_idx];
 687         uint16_t n_descs;
 688
 689         while (desc_is_avail(&vring->desc[vq->used_idx],
 690                              vq->used_wrap_counter)) {
 691
 692                 n_descs = virtio_user_handle_ctrl_msg_packed(dev, vring,
 693                                 vq->used_idx);
 694
 695                 rte_smp_wmb();
 696                 vring->desc[vq->used_idx].flags =
 697                         VRING_DESC_F_WRITE |
 698                         VRING_DESC_F_AVAIL(vq->used_wrap_counter) |
 699                         VRING_DESC_F_USED(vq->used_wrap_counter);
 700
 701                 vq->used_idx += n_descs;
 702                 if (vq->used_idx >= dev->queue_size) {
 703                         vq->used_idx -= dev->queue_size;
 704                         vq->used_wrap_counter ^= 1;
 705                 }
 706         }
 707 }
 708
 709 void
 710 virtio_user_handle_cq(struct virtio_user_dev *dev, uint16_t queue_idx)
 711 {
 712         uint16_t avail_idx, desc_idx;
 713         struct vring_used_elem *uep;
 714         uint32_t n_descs;
 715         struct vring *vring = &dev->vrings[queue_idx];
 716
 717         /* Consume avail ring, using used ring idx as first one */
 718         while (vring->used->idx != vring->avail->idx) {
 719                 avail_idx = (vring->used->idx) & (vring->num - 1);
 720                 desc_idx = vring->avail->ring[avail_idx];
 721
 722                 n_descs = virtio_user_handle_ctrl_msg(dev, vring, desc_idx);
 723
 724                 /* Update used ring */
 725                 uep = &vring->used->ring[avail_idx];
 726                 uep->id = desc_idx;
 727                 uep->len = n_descs;
 728
 729                 vring->used->idx++;
 730         }
 731 }