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_string_fns.h>
  17 #include <rte_eal_memconfig.h>
  18
  19 #include "vhost.h"
  20 #include "virtio_user_dev.h"
  21 #include "../virtio_ethdev.h"
  22
  23 #define VIRTIO_USER_MEM_EVENT_CLB_NAME "virtio_user_mem_event_clb"
  24
  25 static int
  26 virtio_user_create_queue(struct virtio_user_dev *dev, uint32_t queue_sel)
  27 {
  28         /* Of all per virtqueue MSGs, make sure VHOST_SET_VRING_CALL come
  29          * firstly because vhost depends on this msg to allocate virtqueue
  30          * pair.
  31          */
  32         struct vhost_vring_file file;
  33
  34         file.index = queue_sel;
  35         file.fd = dev->callfds[queue_sel];
  36         dev->ops->send_request(dev, VHOST_USER_SET_VRING_CALL, &file);
  37
  38         return 0;
  39 }
  40
  41 static int
  42 virtio_user_kick_queue(struct virtio_user_dev *dev, uint32_t queue_sel)
  43 {
  44         struct vhost_vring_file file;
  45         struct vhost_vring_state state;
  46         struct vring *vring = &dev->vrings[queue_sel];
  47         struct vring_packed *pq_vring = &dev->packed_vrings[queue_sel];
  48         struct vhost_vring_addr addr = {
  49                 .index = queue_sel,
  50                 .log_guest_addr = 0,
  51                 .flags = 0, /* disable log */
  52         };
  53
  54         if (dev->features & (1ULL << VIRTIO_F_RING_PACKED)) {
  55                 addr.desc_user_addr =
  56                         (uint64_t)(uintptr_t)pq_vring->desc;
  57                 addr.avail_user_addr =
  58                         (uint64_t)(uintptr_t)pq_vring->driver;
  59                 addr.used_user_addr =
  60                         (uint64_t)(uintptr_t)pq_vring->device;
  61         } else {
  62                 addr.desc_user_addr = (uint64_t)(uintptr_t)vring->desc;
  63                 addr.avail_user_addr = (uint64_t)(uintptr_t)vring->avail;
  64                 addr.used_user_addr = (uint64_t)(uintptr_t)vring->used;
  65         }
  66
  67         state.index = queue_sel;
  68         state.num = vring->num;
  69         dev->ops->send_request(dev, VHOST_USER_SET_VRING_NUM, &state);
  70
  71         state.index = queue_sel;
  72         state.num = 0; /* no reservation */
  73         if (dev->features & (1ULL << VIRTIO_F_RING_PACKED))
  74                 state.num |= (1 << 15);
  75         dev->ops->send_request(dev, VHOST_USER_SET_VRING_BASE, &state);
  76
  77         dev->ops->send_request(dev, VHOST_USER_SET_VRING_ADDR, &addr);
  78
  79         /* Of all per virtqueue MSGs, make sure VHOST_USER_SET_VRING_KICK comes
  80          * lastly because vhost depends on this msg to judge if
  81          * virtio is ready.
  82          */
  83         file.index = queue_sel;
  84         file.fd = dev->kickfds[queue_sel];
  85         dev->ops->send_request(dev, VHOST_USER_SET_VRING_KICK, &file);
  86
  87         return 0;
  88 }
  89
  90 static int
  91 virtio_user_queue_setup(struct virtio_user_dev *dev,
  92                         int (*fn)(struct virtio_user_dev *, uint32_t))
  93 {
  94         uint32_t i, queue_sel;
  95
  96         for (i = 0; i < dev->max_queue_pairs; ++i) {
  97                 queue_sel = 2 * i + VTNET_SQ_RQ_QUEUE_IDX;
  98                 if (fn(dev, queue_sel) < 0) {
  99                         PMD_DRV_LOG(INFO, "setup rx vq fails: %u", i);
 100                         return -1;
 101                 }
 102         }
 103         for (i = 0; i < dev->max_queue_pairs; ++i) {
 104                 queue_sel = 2 * i + VTNET_SQ_TQ_QUEUE_IDX;
 105                 if (fn(dev, queue_sel) < 0) {
 106                         PMD_DRV_LOG(INFO, "setup tx vq fails: %u", i);
 107                         return -1;
 108                 }
 109         }
 110
 111         return 0;
 112 }
 113
 114 int
 115 is_vhost_user_by_type(const char *path)
 116 {
 117         struct stat sb;
 118
 119         if (stat(path, &sb) == -1)
 120                 return 0;
 121
 122         return S_ISSOCK(sb.st_mode);
 123 }
 124
 125 int
 126 virtio_user_start_device(struct virtio_user_dev *dev)
 127 {
 128         struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config;
 129         uint64_t features;
 130         int ret;
 131
 132         /*
 133          * XXX workaround!
 134          *
 135          * We need to make sure that the locks will be
 136          * taken in the correct order to avoid deadlocks.
 137          *
 138          * Before releasing this lock, this thread should
 139          * not trigger any memory hotplug events.
 140          *
 141          * This is a temporary workaround, and should be
 142          * replaced when we get proper supports from the
 143          * memory subsystem in the future.
 144          */
 145         rte_rwlock_read_lock(&mcfg->memory_hotplug_lock);
 146         pthread_mutex_lock(&dev->mutex);
 147
 148         if (is_vhost_user_by_type(dev->path) && dev->vhostfd < 0)
 149                 goto error;
 150
 151         /* Step 0: tell vhost to create queues */
 152         if (virtio_user_queue_setup(dev, virtio_user_create_queue) < 0)
 153                 goto error;
 154
 155         /* Step 1: set features */
 156         features = dev->features;
 157         /* Strip VIRTIO_NET_F_MAC, as MAC address is handled in vdev init */
 158         features &= ~(1ull << VIRTIO_NET_F_MAC);
 159         /* Strip VIRTIO_NET_F_CTRL_VQ, as devices do not really need to know */
 160         features &= ~(1ull << VIRTIO_NET_F_CTRL_VQ);
 161         features &= ~(1ull << VIRTIO_NET_F_STATUS);
 162         ret = dev->ops->send_request(dev, VHOST_USER_SET_FEATURES, &features);
 163         if (ret < 0)
 164                 goto error;
 165         PMD_DRV_LOG(INFO, "set features: %" PRIx64, features);
 166
 167         /* Step 2: share memory regions */
 168         ret = dev->ops->send_request(dev, VHOST_USER_SET_MEM_TABLE, NULL);
 169         if (ret < 0)
 170                 goto error;
 171
 172         /* Step 3: kick queues */
 173         if (virtio_user_queue_setup(dev, virtio_user_kick_queue) < 0)
 174                 goto error;
 175
 176         /* Step 4: enable queues
 177          * we enable the 1st queue pair by default.
 178          */
 179         dev->ops->enable_qp(dev, 0, 1);
 180
 181         dev->started = true;
 182         pthread_mutex_unlock(&dev->mutex);
 183         rte_rwlock_read_unlock(&mcfg->memory_hotplug_lock);
 184
 185         return 0;
 186 error:
 187         pthread_mutex_unlock(&dev->mutex);
 188         rte_rwlock_read_unlock(&mcfg->memory_hotplug_lock);
 189         /* TODO: free resource here or caller to check */
 190         return -1;
 191 }
 192
 193 int virtio_user_stop_device(struct virtio_user_dev *dev)
 194 {
 195         struct vhost_vring_state state;
 196         uint32_t i;
 197         int error = 0;
 198
 199         pthread_mutex_lock(&dev->mutex);
 200         if (!dev->started)
 201                 goto out;
 202
 203         for (i = 0; i < dev->max_queue_pairs; ++i)
 204                 dev->ops->enable_qp(dev, i, 0);
 205
 206         /* Stop the backend. */
 207         for (i = 0; i < dev->max_queue_pairs * 2; ++i) {
 208                 state.index = i;
 209                 if (dev->ops->send_request(dev, VHOST_USER_GET_VRING_BASE,
 210                                            &state) < 0) {
 211                         PMD_DRV_LOG(ERR, "get_vring_base failed, index=%u\n",
 212                                     i);
 213                         error = -1;
 214                         goto out;
 215                 }
 216         }
 217
 218         dev->started = false;
 219 out:
 220         pthread_mutex_unlock(&dev->mutex);
 221
 222         return error;
 223 }
 224
 225 static inline void
 226 parse_mac(struct virtio_user_dev *dev, const char *mac)
 227 {
 228         int i, r;
 229         uint32_t tmp[RTE_ETHER_ADDR_LEN];
 230
 231         if (!mac)
 232                 return;
 233
 234         r = sscanf(mac, "%x:%x:%x:%x:%x:%x", &tmp[0],
 235                         &tmp[1], &tmp[2], &tmp[3], &tmp[4], &tmp[5]);
 236         if (r == RTE_ETHER_ADDR_LEN) {
 237                 for (i = 0; i < RTE_ETHER_ADDR_LEN; ++i)
 238                         dev->mac_addr[i] = (uint8_t)tmp[i];
 239                 dev->mac_specified = 1;
 240         } else {
 241                 /* ignore the wrong mac, use random mac */
 242                 PMD_DRV_LOG(ERR, "wrong format of mac: %s", mac);
 243         }
 244 }
 245
 246 static int
 247 virtio_user_dev_init_notify(struct virtio_user_dev *dev)
 248 {
 249         uint32_t i, j;
 250         int callfd;
 251         int kickfd;
 252
 253         for (i = 0; i < VIRTIO_MAX_VIRTQUEUES; ++i) {
 254                 if (i >= dev->max_queue_pairs * 2) {
 255                         dev->kickfds[i] = -1;
 256                         dev->callfds[i] = -1;
 257                         continue;
 258                 }
 259
 260                 /* May use invalid flag, but some backend uses kickfd and
 261                  * callfd as criteria to judge if dev is alive. so finally we
 262                  * use real event_fd.
 263                  */
 264                 callfd = eventfd(0, EFD_CLOEXEC | EFD_NONBLOCK);
 265                 if (callfd < 0) {
 266                         PMD_DRV_LOG(ERR, "callfd error, %s", strerror(errno));
 267                         break;
 268                 }
 269                 kickfd = eventfd(0, EFD_CLOEXEC | EFD_NONBLOCK);
 270                 if (kickfd < 0) {
 271                         PMD_DRV_LOG(ERR, "kickfd error, %s", strerror(errno));
 272                         break;
 273                 }
 274                 dev->callfds[i] = callfd;
 275                 dev->kickfds[i] = kickfd;
 276         }
 277
 278         if (i < VIRTIO_MAX_VIRTQUEUES) {
 279                 for (j = 0; j <= i; ++j) {
 280                         close(dev->callfds[j]);
 281                         close(dev->kickfds[j]);
 282                 }
 283
 284                 return -1;
 285         }
 286
 287         return 0;
 288 }
 289
 290 static int
 291 virtio_user_fill_intr_handle(struct virtio_user_dev *dev)
 292 {
 293         uint32_t i;
 294         struct rte_eth_dev *eth_dev = &rte_eth_devices[dev->port_id];
 295
 296         if (!eth_dev->intr_handle) {
 297                 eth_dev->intr_handle = malloc(sizeof(*eth_dev->intr_handle));
 298                 if (!eth_dev->intr_handle) {
 299                         PMD_DRV_LOG(ERR, "fail to allocate intr_handle");
 300                         return -1;
 301                 }
 302                 memset(eth_dev->intr_handle, 0, sizeof(*eth_dev->intr_handle));
 303         }
 304
 305         for (i = 0; i < dev->max_queue_pairs; ++i)
 306                 eth_dev->intr_handle->efds[i] = dev->callfds[i];
 307         eth_dev->intr_handle->nb_efd = dev->max_queue_pairs;
 308         eth_dev->intr_handle->max_intr = dev->max_queue_pairs + 1;
 309         eth_dev->intr_handle->type = RTE_INTR_HANDLE_VDEV;
 310         /* For virtio vdev, no need to read counter for clean */
 311         eth_dev->intr_handle->efd_counter_size = 0;
 312         eth_dev->intr_handle->fd = -1;
 313         if (dev->vhostfd >= 0)
 314                 eth_dev->intr_handle->fd = dev->vhostfd;
 315         else if (dev->is_server)
 316                 eth_dev->intr_handle->fd = dev->listenfd;
 317
 318         return 0;
 319 }
 320
 321 static void
 322 virtio_user_mem_event_cb(enum rte_mem_event type __rte_unused,
 323                                                  const void *addr __rte_unused,
 324                                                  size_t len __rte_unused,
 325                                                  void *arg)
 326 {
 327         struct virtio_user_dev *dev = arg;
 328         struct rte_memseg_list *msl;
 329         uint16_t i;
 330
 331         /* ignore externally allocated memory */
 332         msl = rte_mem_virt2memseg_list(addr);
 333         if (msl->external)
 334                 return;
 335
 336         pthread_mutex_lock(&dev->mutex);
 337
 338         if (dev->started == false)
 339                 goto exit;
 340
 341         /* Step 1: pause the active queues */
 342         for (i = 0; i < dev->queue_pairs; i++)
 343                 dev->ops->enable_qp(dev, i, 0);
 344
 345         /* Step 2: update memory regions */
 346         dev->ops->send_request(dev, VHOST_USER_SET_MEM_TABLE, NULL);
 347
 348         /* Step 3: resume the active queues */
 349         for (i = 0; i < dev->queue_pairs; i++)
 350                 dev->ops->enable_qp(dev, i, 1);
 351
 352 exit:
 353         pthread_mutex_unlock(&dev->mutex);
 354 }
 355
 356 static int
 357 virtio_user_dev_setup(struct virtio_user_dev *dev)
 358 {
 359         uint32_t q;
 360
 361         dev->vhostfd = -1;
 362         dev->vhostfds = NULL;
 363         dev->tapfds = NULL;
 364
 365         if (dev->is_server) {
 366                 if (access(dev->path, F_OK) == 0 &&
 367                     !is_vhost_user_by_type(dev->path)) {
 368                         PMD_DRV_LOG(ERR, "Server mode doesn't support vhost-kernel!");
 369                         return -1;
 370                 }
 371                 dev->ops = &virtio_ops_user;
 372         } else {
 373                 if (is_vhost_user_by_type(dev->path)) {
 374                         dev->ops = &virtio_ops_user;
 375                 } else {
 376                         dev->ops = &virtio_ops_kernel;
 377
 378                         dev->vhostfds = malloc(dev->max_queue_pairs *
 379                                                sizeof(int));
 380                         dev->tapfds = malloc(dev->max_queue_pairs *
 381                                              sizeof(int));
 382                         if (!dev->vhostfds || !dev->tapfds) {
 383                                 PMD_INIT_LOG(ERR, "Failed to malloc");
 384                                 return -1;
 385                         }
 386
 387                         for (q = 0; q < dev->max_queue_pairs; ++q) {
 388                                 dev->vhostfds[q] = -1;
 389                                 dev->tapfds[q] = -1;
 390                         }
 391                 }
 392         }
 393
 394         if (dev->ops->setup(dev) < 0)
 395                 return -1;
 396
 397         if (virtio_user_dev_init_notify(dev) < 0)
 398                 return -1;
 399
 400         if (virtio_user_fill_intr_handle(dev) < 0)
 401                 return -1;
 402
 403         return 0;
 404 }
 405
 406 /* Use below macro to filter features from vhost backend */
 407 #define VIRTIO_USER_SUPPORTED_FEATURES                  \
 408         (1ULL << VIRTIO_NET_F_MAC               |       \
 409          1ULL << VIRTIO_NET_F_STATUS            |       \
 410          1ULL << VIRTIO_NET_F_MQ                |       \
 411          1ULL << VIRTIO_NET_F_CTRL_MAC_ADDR     |       \
 412          1ULL << VIRTIO_NET_F_CTRL_VQ           |       \
 413          1ULL << VIRTIO_NET_F_CTRL_RX           |       \
 414          1ULL << VIRTIO_NET_F_CTRL_VLAN         |       \
 415          1ULL << VIRTIO_NET_F_CSUM              |       \
 416          1ULL << VIRTIO_NET_F_HOST_TSO4         |       \
 417          1ULL << VIRTIO_NET_F_HOST_TSO6         |       \
 418          1ULL << VIRTIO_NET_F_MRG_RXBUF         |       \
 419          1ULL << VIRTIO_RING_F_INDIRECT_DESC    |       \
 420          1ULL << VIRTIO_NET_F_GUEST_CSUM        |       \
 421          1ULL << VIRTIO_NET_F_GUEST_TSO4        |       \
 422          1ULL << VIRTIO_NET_F_GUEST_TSO6        |       \
 423          1ULL << VIRTIO_F_IN_ORDER              |       \
 424          1ULL << VIRTIO_F_VERSION_1             |       \
 425          1ULL << VIRTIO_F_RING_PACKED)
 426
 427 int
 428 virtio_user_dev_init(struct virtio_user_dev *dev, char *path, int queues,
 429                      int cq, int queue_size, const char *mac, char **ifname,
 430                      int server, int mrg_rxbuf, int in_order, int packed_vq)
 431 {
 432         pthread_mutex_init(&dev->mutex, NULL);
 433         strlcpy(dev->path, path, PATH_MAX);
 434         dev->started = 0;
 435         dev->max_queue_pairs = queues;
 436         dev->queue_pairs = 1; /* mq disabled by default */
 437         dev->queue_size = queue_size;
 438         dev->is_server = server;
 439         dev->mac_specified = 0;
 440         dev->frontend_features = 0;
 441         dev->unsupported_features = ~VIRTIO_USER_SUPPORTED_FEATURES;
 442         parse_mac(dev, mac);
 443
 444         if (*ifname) {
 445                 dev->ifname = *ifname;
 446                 *ifname = NULL;
 447         }
 448
 449         if (virtio_user_dev_setup(dev) < 0) {
 450                 PMD_INIT_LOG(ERR, "backend set up fails");
 451                 return -1;
 452         }
 453
 454         if (!dev->is_server) {
 455                 if (dev->ops->send_request(dev, VHOST_USER_SET_OWNER,
 456                                            NULL) < 0) {
 457                         PMD_INIT_LOG(ERR, "set_owner fails: %s",
 458                                      strerror(errno));
 459                         return -1;
 460                 }
 461
 462                 if (dev->ops->send_request(dev, VHOST_USER_GET_FEATURES,
 463                                            &dev->device_features) < 0) {
 464                         PMD_INIT_LOG(ERR, "get_features failed: %s",
 465                                      strerror(errno));
 466                         return -1;
 467                 }
 468         } else {
 469                 /* We just pretend vhost-user can support all these features.
 470                  * Note that this could be problematic that if some feature is
 471                  * negotiated but not supported by the vhost-user which comes
 472                  * later.
 473                  */
 474                 dev->device_features = VIRTIO_USER_SUPPORTED_FEATURES;
 475         }
 476
 477         if (!mrg_rxbuf)
 478                 dev->unsupported_features |= (1ull << VIRTIO_NET_F_MRG_RXBUF);
 479
 480         if (!in_order)
 481                 dev->unsupported_features |= (1ull << VIRTIO_F_IN_ORDER);
 482
 483         if (!packed_vq)
 484                 dev->unsupported_features |= (1ull << VIRTIO_F_RING_PACKED);
 485
 486         if (dev->mac_specified)
 487                 dev->frontend_features |= (1ull << VIRTIO_NET_F_MAC);
 488         else
 489                 dev->unsupported_features |= (1ull << VIRTIO_NET_F_MAC);
 490
 491         if (cq) {
 492                 /* device does not really need to know anything about CQ,
 493                  * so if necessary, we just claim to support CQ
 494                  */
 495                 dev->frontend_features |= (1ull << VIRTIO_NET_F_CTRL_VQ);
 496         } else {
 497                 dev->unsupported_features |= (1ull << VIRTIO_NET_F_CTRL_VQ);
 498                 /* Also disable features that depend on VIRTIO_NET_F_CTRL_VQ */
 499                 dev->unsupported_features |= (1ull << VIRTIO_NET_F_CTRL_RX);
 500                 dev->unsupported_features |= (1ull << VIRTIO_NET_F_CTRL_VLAN);
 501                 dev->unsupported_features |=
 502                         (1ull << VIRTIO_NET_F_GUEST_ANNOUNCE);
 503                 dev->unsupported_features |= (1ull << VIRTIO_NET_F_MQ);
 504                 dev->unsupported_features |=
 505                         (1ull << VIRTIO_NET_F_CTRL_MAC_ADDR);
 506         }
 507
 508         /* The backend will not report this feature, we add it explicitly */
 509         if (is_vhost_user_by_type(dev->path))
 510                 dev->frontend_features |= (1ull << VIRTIO_NET_F_STATUS);
 511
 512         /*
 513          * Device features =
 514          *     (frontend_features | backend_features) & ~unsupported_features;
 515          */
 516         dev->device_features |= dev->frontend_features;
 517         dev->device_features &= ~dev->unsupported_features;
 518
 519         if (rte_mem_event_callback_register(VIRTIO_USER_MEM_EVENT_CLB_NAME,
 520                                 virtio_user_mem_event_cb, dev)) {
 521                 if (rte_errno != ENOTSUP) {
 522                         PMD_INIT_LOG(ERR, "Failed to register mem event"
 523                                         " callback\n");
 524                         return -1;
 525                 }
 526         }
 527
 528         return 0;
 529 }
 530
 531 void
 532 virtio_user_dev_uninit(struct virtio_user_dev *dev)
 533 {
 534         uint32_t i;
 535
 536         virtio_user_stop_device(dev);
 537
 538         rte_mem_event_callback_unregister(VIRTIO_USER_MEM_EVENT_CLB_NAME, dev);
 539
 540         for (i = 0; i < dev->max_queue_pairs * 2; ++i) {
 541                 close(dev->callfds[i]);
 542                 close(dev->kickfds[i]);
 543         }
 544
 545         close(dev->vhostfd);
 546
 547         if (dev->is_server && dev->listenfd >= 0) {
 548                 close(dev->listenfd);
 549                 dev->listenfd = -1;
 550         }
 551
 552         if (dev->vhostfds) {
 553                 for (i = 0; i < dev->max_queue_pairs; ++i)
 554                         close(dev->vhostfds[i]);
 555                 free(dev->vhostfds);
 556                 free(dev->tapfds);
 557         }
 558
 559         free(dev->ifname);
 560
 561         if (dev->is_server)
 562                 unlink(dev->path);
 563 }
 564
 565 uint8_t
 566 virtio_user_handle_mq(struct virtio_user_dev *dev, uint16_t q_pairs)
 567 {
 568         uint16_t i;
 569         uint8_t ret = 0;
 570
 571         if (q_pairs > dev->max_queue_pairs) {
 572                 PMD_INIT_LOG(ERR, "multi-q config %u, but only %u supported",
 573                              q_pairs, dev->max_queue_pairs);
 574                 return -1;
 575         }
 576
 577         /* Server mode can't enable queue pairs if vhostfd is invalid,
 578          * always return 0 in this case.
 579          */
 580         if (!dev->is_server || dev->vhostfd >= 0) {
 581                 for (i = 0; i < q_pairs; ++i)
 582                         ret |= dev->ops->enable_qp(dev, i, 1);
 583                 for (i = q_pairs; i < dev->max_queue_pairs; ++i)
 584                         ret |= dev->ops->enable_qp(dev, i, 0);
 585         }
 586         dev->queue_pairs = q_pairs;
 587
 588         return ret;
 589 }
 590
 591 static uint32_t
 592 virtio_user_handle_ctrl_msg(struct virtio_user_dev *dev, struct vring *vring,
 593                             uint16_t idx_hdr)
 594 {
 595         struct virtio_net_ctrl_hdr *hdr;
 596         virtio_net_ctrl_ack status = ~0;
 597         uint16_t i, idx_data, idx_status;
 598         uint32_t n_descs = 0;
 599
 600         /* locate desc for header, data, and status */
 601         idx_data = vring->desc[idx_hdr].next;
 602         n_descs++;
 603
 604         i = idx_data;
 605         while (vring->desc[i].flags == VRING_DESC_F_NEXT) {
 606                 i = vring->desc[i].next;
 607                 n_descs++;
 608         }
 609
 610         /* locate desc for status */
 611         idx_status = i;
 612         n_descs++;
 613
 614         hdr = (void *)(uintptr_t)vring->desc[idx_hdr].addr;
 615         if (hdr->class == VIRTIO_NET_CTRL_MQ &&
 616             hdr->cmd == VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET) {
 617                 uint16_t queues;
 618
 619                 queues = *(uint16_t *)(uintptr_t)vring->desc[idx_data].addr;
 620                 status = virtio_user_handle_mq(dev, queues);
 621         }
 622
 623         /* Update status */
 624         *(virtio_net_ctrl_ack *)(uintptr_t)vring->desc[idx_status].addr = status;
 625
 626         return n_descs;
 627 }
 628
 629 static inline int
 630 desc_is_avail(struct vring_packed_desc *desc, bool wrap_counter)
 631 {
 632         uint16_t flags = desc->flags;
 633
 634         return wrap_counter == !!(flags & VRING_PACKED_DESC_F_AVAIL) &&
 635                 wrap_counter != !!(flags & VRING_PACKED_DESC_F_USED);
 636 }
 637
 638 static uint32_t
 639 virtio_user_handle_ctrl_msg_packed(struct virtio_user_dev *dev,
 640                                    struct vring_packed *vring,
 641                                    uint16_t idx_hdr)
 642 {
 643         struct virtio_net_ctrl_hdr *hdr;
 644         virtio_net_ctrl_ack status = ~0;
 645         uint16_t idx_data, idx_status;
 646         /* initialize to one, header is first */
 647         uint32_t n_descs = 1;
 648
 649         /* locate desc for header, data, and status */
 650         idx_data = idx_hdr + 1;
 651         if (idx_data >= dev->queue_size)
 652                 idx_data -= dev->queue_size;
 653
 654         n_descs++;
 655
 656         idx_status = idx_data;
 657         while (vring->desc[idx_status].flags & VRING_DESC_F_NEXT) {
 658                 idx_status++;
 659                 if (idx_status >= dev->queue_size)
 660                         idx_status -= dev->queue_size;
 661                 n_descs++;
 662         }
 663
 664         hdr = (void *)(uintptr_t)vring->desc[idx_hdr].addr;
 665         if (hdr->class == VIRTIO_NET_CTRL_MQ &&
 666             hdr->cmd == VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET) {
 667                 uint16_t queues;
 668
 669                 queues = *(uint16_t *)(uintptr_t)
 670                                 vring->desc[idx_data].addr;
 671                 status = virtio_user_handle_mq(dev, queues);
 672         }
 673
 674         /* Update status */
 675         *(virtio_net_ctrl_ack *)(uintptr_t)
 676                 vring->desc[idx_status].addr = status;
 677
 678         /* Update used descriptor */
 679         vring->desc[idx_hdr].id = vring->desc[idx_status].id;
 680         vring->desc[idx_hdr].len = sizeof(status);
 681
 682         return n_descs;
 683 }
 684
 685 void
 686 virtio_user_handle_cq_packed(struct virtio_user_dev *dev, uint16_t queue_idx)
 687 {
 688         struct virtio_user_queue *vq = &dev->packed_queues[queue_idx];
 689         struct vring_packed *vring = &dev->packed_vrings[queue_idx];
 690         uint16_t n_descs, flags;
 691
 692         while (desc_is_avail(&vring->desc[vq->used_idx],
 693                              vq->used_wrap_counter)) {
 694
 695                 n_descs = virtio_user_handle_ctrl_msg_packed(dev, vring,
 696                                 vq->used_idx);
 697
 698                 flags = VRING_DESC_F_WRITE;
 699                 if (vq->used_wrap_counter)
 700                         flags |= VRING_PACKED_DESC_F_AVAIL_USED;
 701
 702                 rte_smp_wmb();
 703                 vring->desc[vq->used_idx].flags = flags;
 704
 705                 vq->used_idx += n_descs;
 706                 if (vq->used_idx >= dev->queue_size) {
 707                         vq->used_idx -= dev->queue_size;
 708                         vq->used_wrap_counter ^= 1;
 709                 }
 710         }
 711 }
 712
 713 void
 714 virtio_user_handle_cq(struct virtio_user_dev *dev, uint16_t queue_idx)
 715 {
 716         uint16_t avail_idx, desc_idx;
 717         struct vring_used_elem *uep;
 718         uint32_t n_descs;
 719         struct vring *vring = &dev->vrings[queue_idx];
 720
 721         /* Consume avail ring, using used ring idx as first one */
 722         while (vring->used->idx != vring->avail->idx) {
 723                 avail_idx = (vring->used->idx) & (vring->num - 1);
 724                 desc_idx = vring->avail->ring[avail_idx];
 725
 726                 n_descs = virtio_user_handle_ctrl_msg(dev, vring, desc_idx);
 727
 728                 /* Update used ring */
 729                 uep = &vring->used->ring[avail_idx];
 730                 uep->id = desc_idx;
 731                 uep->len = n_descs;
 732
 733                 vring->used->idx++;
 734         }
 735 }