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