drivers/net/xen-netback/interface.c

   1 /*
   2  * Network-device interface management.
   3  *
   4  * Copyright (c) 2004-2005, Keir Fraser
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License version 2
   8  * as published by the Free Software Foundation; or, when distributed
   9  * separately from the Linux kernel or incorporated into other
  10  * software packages, subject to the following license:
  11  *
  12  * Permission is hereby granted, free of charge, to any person obtaining a copy
  13  * of this source file (the "Software"), to deal in the Software without
  14  * restriction, including without limitation the rights to use, copy, modify,
  15  * merge, publish, distribute, sublicense, and/or sell copies of the Software,
  16  * and to permit persons to whom the Software is furnished to do so, subject to
  17  * the following conditions:
  18  *
  19  * The above copyright notice and this permission notice shall be included in
  20  * all copies or substantial portions of the Software.
  21  *
  22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  23  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  25  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  26  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  27  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  28  * IN THE SOFTWARE.
  29  */
  30
  31 #include "common.h"
  32
  33 #include <linux/kthread.h>
  34 #include <linux/ethtool.h>
  35 #include <linux/rtnetlink.h>
  36 #include <linux/if_vlan.h>
  37 #include <linux/vmalloc.h>
  38
  39 #include <xen/events.h>
  40 #include <asm/xen/hypercall.h>
  41 #include <xen/balloon.h>
  42
  43 #define XENVIF_QUEUE_LENGTH 32
  44 #define XENVIF_NAPI_WEIGHT  64
  45
  46 /* Number of bytes allowed on the internal guest Rx queue. */
  47 #define XENVIF_RX_QUEUE_BYTES (XEN_NETIF_RX_RING_SIZE/2 * PAGE_SIZE)
  48
  49 /* This function is used to set SKBTX_DEV_ZEROCOPY as well as
  50  * increasing the inflight counter. We need to increase the inflight
  51  * counter because core driver calls into xenvif_zerocopy_callback
  52  * which calls xenvif_skb_zerocopy_complete.
  53  */
  54 void xenvif_skb_zerocopy_prepare(struct xenvif_queue *queue,
  55                                  struct sk_buff *skb)
  56 {
  57         skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY;
  58         atomic_inc(&queue->inflight_packets);
  59 }
  60
  61 void xenvif_skb_zerocopy_complete(struct xenvif_queue *queue)
  62 {
  63         atomic_dec(&queue->inflight_packets);
  64 }
  65
  66 int xenvif_schedulable(struct xenvif *vif)
  67 {
  68         return netif_running(vif->dev) &&
  69                 test_bit(VIF_STATUS_CONNECTED, &vif->status) &&
  70                 !vif->disabled;
  71 }
  72
  73 static irqreturn_t xenvif_tx_interrupt(int irq, void *dev_id)
  74 {
  75         struct xenvif_queue *queue = dev_id;
  76
  77         if (RING_HAS_UNCONSUMED_REQUESTS(&queue->tx))
  78                 napi_schedule(&queue->napi);
  79
  80         return IRQ_HANDLED;
  81 }
  82
  83 static int xenvif_poll(struct napi_struct *napi, int budget)
  84 {
  85         struct xenvif_queue *queue =
  86                 container_of(napi, struct xenvif_queue, napi);
  87         int work_done;
  88
  89         /* This vif is rogue, we pretend we've there is nothing to do
  90          * for this vif to deschedule it from NAPI. But this interface
  91          * will be turned off in thread context later.
  92          */
  93         if (unlikely(queue->vif->disabled)) {
  94                 napi_complete(napi);
  95                 return 0;
  96         }
  97
  98         work_done = xenvif_tx_action(queue, budget);
  99
 100         if (work_done < budget) {
 101                 napi_complete(napi);
 102                 xenvif_napi_schedule_or_enable_events(queue);
 103         }
 104
 105         return work_done;
 106 }
 107
 108 static irqreturn_t xenvif_rx_interrupt(int irq, void *dev_id)
 109 {
 110         struct xenvif_queue *queue = dev_id;
 111
 112         xenvif_kick_thread(queue);
 113
 114         return IRQ_HANDLED;
 115 }
 116
 117 irqreturn_t xenvif_interrupt(int irq, void *dev_id)
 118 {
 119         xenvif_tx_interrupt(irq, dev_id);
 120         xenvif_rx_interrupt(irq, dev_id);
 121
 122         return IRQ_HANDLED;
 123 }
 124
 125 int xenvif_queue_stopped(struct xenvif_queue *queue)
 126 {
 127         struct net_device *dev = queue->vif->dev;
 128         unsigned int id = queue->id;
 129         return netif_tx_queue_stopped(netdev_get_tx_queue(dev, id));
 130 }
 131
 132 void xenvif_wake_queue(struct xenvif_queue *queue)
 133 {
 134         struct net_device *dev = queue->vif->dev;
 135         unsigned int id = queue->id;
 136         netif_tx_wake_queue(netdev_get_tx_queue(dev, id));
 137 }
 138
 139 static int xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev)
 140 {
 141         struct xenvif *vif = netdev_priv(dev);
 142         struct xenvif_queue *queue = NULL;
 143         unsigned int num_queues = vif->num_queues;
 144         u16 index;
 145         struct xenvif_rx_cb *cb;
 146
 147         BUG_ON(skb->dev != dev);
 148
 149         /* Drop the packet if queues are not set up */
 150         if (num_queues < 1)
 151                 goto drop;
 152
 153         /* Obtain the queue to be used to transmit this packet */
 154         index = skb_get_queue_mapping(skb);
 155         if (index >= num_queues) {
 156                 pr_warn_ratelimited("Invalid queue %hu for packet on interface %s\n.",
 157                                     index, vif->dev->name);
 158                 index %= num_queues;
 159         }
 160         queue = &vif->queues[index];
 161
 162         /* Drop the packet if queue is not ready */
 163         if (queue->task == NULL ||
 164             queue->dealloc_task == NULL ||
 165             !xenvif_schedulable(vif))
 166                 goto drop;
 167
 168         cb = XENVIF_RX_CB(skb);
 169         cb->expires = jiffies + vif->drain_timeout;
 170
 171         xenvif_rx_queue_tail(queue, skb);
 172         xenvif_kick_thread(queue);
 173
 174         return NETDEV_TX_OK;
 175
 176  drop:
 177         vif->dev->stats.tx_dropped++;
 178         dev_kfree_skb(skb);
 179         return NETDEV_TX_OK;
 180 }
 181
 182 static struct net_device_stats *xenvif_get_stats(struct net_device *dev)
 183 {
 184         struct xenvif *vif = netdev_priv(dev);
 185         struct xenvif_queue *queue = NULL;
 186         unsigned int num_queues = vif->num_queues;
 187         unsigned long rx_bytes = 0;
 188         unsigned long rx_packets = 0;
 189         unsigned long tx_bytes = 0;
 190         unsigned long tx_packets = 0;
 191         unsigned int index;
 192
 193         if (vif->queues == NULL)
 194                 goto out;
 195
 196         /* Aggregate tx and rx stats from each queue */
 197         for (index = 0; index < num_queues; ++index) {
 198                 queue = &vif->queues[index];
 199                 rx_bytes += queue->stats.rx_bytes;
 200                 rx_packets += queue->stats.rx_packets;
 201                 tx_bytes += queue->stats.tx_bytes;
 202                 tx_packets += queue->stats.tx_packets;
 203         }
 204
 205 out:
 206         vif->dev->stats.rx_bytes = rx_bytes;
 207         vif->dev->stats.rx_packets = rx_packets;
 208         vif->dev->stats.tx_bytes = tx_bytes;
 209         vif->dev->stats.tx_packets = tx_packets;
 210
 211         return &vif->dev->stats;
 212 }
 213
 214 static void xenvif_up(struct xenvif *vif)
 215 {
 216         struct xenvif_queue *queue = NULL;
 217         unsigned int num_queues = vif->num_queues;
 218         unsigned int queue_index;
 219
 220         for (queue_index = 0; queue_index < num_queues; ++queue_index) {
 221                 queue = &vif->queues[queue_index];
 222                 napi_enable(&queue->napi);
 223                 enable_irq(queue->tx_irq);
 224                 if (queue->tx_irq != queue->rx_irq)
 225                         enable_irq(queue->rx_irq);
 226                 xenvif_napi_schedule_or_enable_events(queue);
 227         }
 228 }
 229
 230 static void xenvif_down(struct xenvif *vif)
 231 {
 232         struct xenvif_queue *queue = NULL;
 233         unsigned int num_queues = vif->num_queues;
 234         unsigned int queue_index;
 235
 236         for (queue_index = 0; queue_index < num_queues; ++queue_index) {
 237                 queue = &vif->queues[queue_index];
 238                 disable_irq(queue->tx_irq);
 239                 if (queue->tx_irq != queue->rx_irq)
 240                         disable_irq(queue->rx_irq);
 241                 napi_disable(&queue->napi);
 242                 del_timer_sync(&queue->credit_timeout);
 243         }
 244 }
 245
 246 static int xenvif_open(struct net_device *dev)
 247 {
 248         struct xenvif *vif = netdev_priv(dev);
 249         if (test_bit(VIF_STATUS_CONNECTED, &vif->status))
 250                 xenvif_up(vif);
 251         netif_tx_start_all_queues(dev);
 252         return 0;
 253 }
 254
 255 static int xenvif_close(struct net_device *dev)
 256 {
 257         struct xenvif *vif = netdev_priv(dev);
 258         if (test_bit(VIF_STATUS_CONNECTED, &vif->status))
 259                 xenvif_down(vif);
 260         netif_tx_stop_all_queues(dev);
 261         return 0;
 262 }
 263
 264 static int xenvif_change_mtu(struct net_device *dev, int mtu)
 265 {
 266         struct xenvif *vif = netdev_priv(dev);
 267         int max = vif->can_sg ? 65535 - VLAN_ETH_HLEN : ETH_DATA_LEN;
 268
 269         if (mtu > max)
 270                 return -EINVAL;
 271         dev->mtu = mtu;
 272         return 0;
 273 }
 274
 275 static netdev_features_t xenvif_fix_features(struct net_device *dev,
 276         netdev_features_t features)
 277 {
 278         struct xenvif *vif = netdev_priv(dev);
 279
 280         if (!vif->can_sg)
 281                 features &= ~NETIF_F_SG;
 282         if (~(vif->gso_mask | vif->gso_prefix_mask) & GSO_BIT(TCPV4))
 283                 features &= ~NETIF_F_TSO;
 284         if (~(vif->gso_mask | vif->gso_prefix_mask) & GSO_BIT(TCPV6))
 285                 features &= ~NETIF_F_TSO6;
 286         if (!vif->ip_csum)
 287                 features &= ~NETIF_F_IP_CSUM;
 288         if (!vif->ipv6_csum)
 289                 features &= ~NETIF_F_IPV6_CSUM;
 290
 291         return features;
 292 }
 293
 294 static const struct xenvif_stat {
 295         char name[ETH_GSTRING_LEN];
 296         u16 offset;
 297 } xenvif_stats[] = {
 298         {
 299                 "rx_gso_checksum_fixup",
 300                 offsetof(struct xenvif_stats, rx_gso_checksum_fixup)
 301         },
 302         /* If (sent != success + fail), there are probably packets never
 303          * freed up properly!
 304          */
 305         {
 306                 "tx_zerocopy_sent",
 307                 offsetof(struct xenvif_stats, tx_zerocopy_sent),
 308         },
 309         {
 310                 "tx_zerocopy_success",
 311                 offsetof(struct xenvif_stats, tx_zerocopy_success),
 312         },
 313         {
 314                 "tx_zerocopy_fail",
 315                 offsetof(struct xenvif_stats, tx_zerocopy_fail)
 316         },
 317         /* Number of packets exceeding MAX_SKB_FRAG slots. You should use
 318          * a guest with the same MAX_SKB_FRAG
 319          */
 320         {
 321                 "tx_frag_overflow",
 322                 offsetof(struct xenvif_stats, tx_frag_overflow)
 323         },
 324 };
 325
 326 static int xenvif_get_sset_count(struct net_device *dev, int string_set)
 327 {
 328         switch (string_set) {
 329         case ETH_SS_STATS:
 330                 return ARRAY_SIZE(xenvif_stats);
 331         default:
 332                 return -EINVAL;
 333         }
 334 }
 335
 336 static void xenvif_get_ethtool_stats(struct net_device *dev,
 337                                      struct ethtool_stats *stats, u64 * data)
 338 {
 339         struct xenvif *vif = netdev_priv(dev);
 340         unsigned int num_queues = vif->num_queues;
 341         int i;
 342         unsigned int queue_index;
 343
 344         for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++) {
 345                 unsigned long accum = 0;
 346                 for (queue_index = 0; queue_index < num_queues; ++queue_index) {
 347                         void *vif_stats = &vif->queues[queue_index].stats;
 348                         accum += *(unsigned long *)(vif_stats + xenvif_stats[i].offset);
 349                 }
 350                 data[i] = accum;
 351         }
 352 }
 353
 354 static void xenvif_get_strings(struct net_device *dev, u32 stringset, u8 * data)
 355 {
 356         int i;
 357
 358         switch (stringset) {
 359         case ETH_SS_STATS:
 360                 for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++)
 361                         memcpy(data + i * ETH_GSTRING_LEN,
 362                                xenvif_stats[i].name, ETH_GSTRING_LEN);
 363                 break;
 364         }
 365 }
 366
 367 static const struct ethtool_ops xenvif_ethtool_ops = {
 368         .get_link       = ethtool_op_get_link,
 369
 370         .get_sset_count = xenvif_get_sset_count,
 371         .get_ethtool_stats = xenvif_get_ethtool_stats,
 372         .get_strings = xenvif_get_strings,
 373 };
 374
 375 static const struct net_device_ops xenvif_netdev_ops = {
 376         .ndo_start_xmit = xenvif_start_xmit,
 377         .ndo_get_stats  = xenvif_get_stats,
 378         .ndo_open       = xenvif_open,
 379         .ndo_stop       = xenvif_close,
 380         .ndo_change_mtu = xenvif_change_mtu,
 381         .ndo_fix_features = xenvif_fix_features,
 382         .ndo_set_mac_address = eth_mac_addr,
 383         .ndo_validate_addr   = eth_validate_addr,
 384 };
 385
 386 struct xenvif *xenvif_alloc(struct device *parent, domid_t domid,
 387                             unsigned int handle)
 388 {
 389         int err;
 390         struct net_device *dev;
 391         struct xenvif *vif;
 392         char name[IFNAMSIZ] = {};
 393
 394         snprintf(name, IFNAMSIZ - 1, "vif%u.%u", domid, handle);
 395         /* Allocate a netdev with the max. supported number of queues.
 396          * When the guest selects the desired number, it will be updated
 397          * via netif_set_real_num_*_queues().
 398          */
 399         dev = alloc_netdev_mq(sizeof(struct xenvif), name, NET_NAME_UNKNOWN,
 400                               ether_setup, xenvif_max_queues);
 401         if (dev == NULL) {
 402                 pr_warn("Could not allocate netdev for %s\n", name);
 403                 return ERR_PTR(-ENOMEM);
 404         }
 405
 406         SET_NETDEV_DEV(dev, parent);
 407
 408         vif = netdev_priv(dev);
 409
 410         vif->domid  = domid;
 411         vif->handle = handle;
 412         vif->can_sg = 1;
 413         vif->ip_csum = 1;
 414         vif->dev = dev;
 415         vif->disabled = false;
 416         vif->drain_timeout = msecs_to_jiffies(rx_drain_timeout_msecs);
 417         vif->stall_timeout = msecs_to_jiffies(rx_stall_timeout_msecs);
 418
 419         /* Start out with no queues. */
 420         vif->queues = NULL;
 421         vif->num_queues = 0;
 422
 423         spin_lock_init(&vif->lock);
 424
 425         dev->netdev_ops = &xenvif_netdev_ops;
 426         dev->hw_features = NETIF_F_SG |
 427                 NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM |
 428                 NETIF_F_TSO | NETIF_F_TSO6;
 429         dev->features = dev->hw_features | NETIF_F_RXCSUM;
 430         dev->ethtool_ops = &xenvif_ethtool_ops;
 431
 432         dev->tx_queue_len = XENVIF_QUEUE_LENGTH;
 433
 434         /*
 435          * Initialise a dummy MAC address. We choose the numerically
 436          * largest non-broadcast address to prevent the address getting
 437          * stolen by an Ethernet bridge for STP purposes.
 438          * (FE:FF:FF:FF:FF:FF)
 439          */
 440         eth_broadcast_addr(dev->dev_addr);
 441         dev->dev_addr[0] &= ~0x01;
 442
 443         netif_carrier_off(dev);
 444
 445         err = register_netdev(dev);
 446         if (err) {
 447                 netdev_warn(dev, "Could not register device: err=%d\n", err);
 448                 free_netdev(dev);
 449                 return ERR_PTR(err);
 450         }
 451
 452         netdev_dbg(dev, "Successfully created xenvif\n");
 453
 454         __module_get(THIS_MODULE);
 455
 456         return vif;
 457 }
 458
 459 int xenvif_init_queue(struct xenvif_queue *queue)
 460 {
 461         int err, i;
 462
 463         queue->credit_bytes = queue->remaining_credit = ~0UL;
 464         queue->credit_usec  = 0UL;
 465         init_timer(&queue->credit_timeout);
 466         queue->credit_timeout.function = xenvif_tx_credit_callback;
 467         queue->credit_window_start = get_jiffies_64();
 468
 469         queue->rx_queue_max = XENVIF_RX_QUEUE_BYTES;
 470
 471         skb_queue_head_init(&queue->rx_queue);
 472         skb_queue_head_init(&queue->tx_queue);
 473
 474         queue->pending_cons = 0;
 475         queue->pending_prod = MAX_PENDING_REQS;
 476         for (i = 0; i < MAX_PENDING_REQS; ++i)
 477                 queue->pending_ring[i] = i;
 478
 479         spin_lock_init(&queue->callback_lock);
 480         spin_lock_init(&queue->response_lock);
 481
 482         /* If ballooning is disabled, this will consume real memory, so you
 483          * better enable it. The long term solution would be to use just a
 484          * bunch of valid page descriptors, without dependency on ballooning
 485          */
 486         err = gnttab_alloc_pages(MAX_PENDING_REQS,
 487                                  queue->mmap_pages);
 488         if (err) {
 489                 netdev_err(queue->vif->dev, "Could not reserve mmap_pages\n");
 490                 return -ENOMEM;
 491         }
 492
 493         for (i = 0; i < MAX_PENDING_REQS; i++) {
 494                 queue->pending_tx_info[i].callback_struct = (struct ubuf_info)
 495                         { .callback = xenvif_zerocopy_callback,
 496                           .ctx = NULL,
 497                           .desc = i };
 498                 queue->grant_tx_handle[i] = NETBACK_INVALID_HANDLE;
 499         }
 500
 501         return 0;
 502 }
 503
 504 void xenvif_carrier_on(struct xenvif *vif)
 505 {
 506         rtnl_lock();
 507         if (!vif->can_sg && vif->dev->mtu > ETH_DATA_LEN)
 508                 dev_set_mtu(vif->dev, ETH_DATA_LEN);
 509         netdev_update_features(vif->dev);
 510         set_bit(VIF_STATUS_CONNECTED, &vif->status);
 511         if (netif_running(vif->dev))
 512                 xenvif_up(vif);
 513         rtnl_unlock();
 514 }
 515
 516 int xenvif_connect(struct xenvif_queue *queue, unsigned long tx_ring_ref,
 517                    unsigned long rx_ring_ref, unsigned int tx_evtchn,
 518                    unsigned int rx_evtchn)
 519 {
 520         struct task_struct *task;
 521         int err = -ENOMEM;
 522
 523         BUG_ON(queue->tx_irq);
 524         BUG_ON(queue->task);
 525         BUG_ON(queue->dealloc_task);
 526
 527         err = xenvif_map_frontend_rings(queue, tx_ring_ref, rx_ring_ref);
 528         if (err < 0)
 529                 goto err;
 530
 531         init_waitqueue_head(&queue->wq);
 532         init_waitqueue_head(&queue->dealloc_wq);
 533         atomic_set(&queue->inflight_packets, 0);
 534
 535         netif_napi_add(queue->vif->dev, &queue->napi, xenvif_poll,
 536                         XENVIF_NAPI_WEIGHT);
 537
 538         if (tx_evtchn == rx_evtchn) {
 539                 /* feature-split-event-channels == 0 */
 540                 err = bind_interdomain_evtchn_to_irqhandler(
 541                         queue->vif->domid, tx_evtchn, xenvif_interrupt, 0,
 542                         queue->name, queue);
 543                 if (err < 0)
 544                         goto err_unmap;
 545                 queue->tx_irq = queue->rx_irq = err;
 546                 disable_irq(queue->tx_irq);
 547         } else {
 548                 /* feature-split-event-channels == 1 */
 549                 snprintf(queue->tx_irq_name, sizeof(queue->tx_irq_name),
 550                          "%s-tx", queue->name);
 551                 err = bind_interdomain_evtchn_to_irqhandler(
 552                         queue->vif->domid, tx_evtchn, xenvif_tx_interrupt, 0,
 553                         queue->tx_irq_name, queue);
 554                 if (err < 0)
 555                         goto err_unmap;
 556                 queue->tx_irq = err;
 557                 disable_irq(queue->tx_irq);
 558
 559                 snprintf(queue->rx_irq_name, sizeof(queue->rx_irq_name),
 560                          "%s-rx", queue->name);
 561                 err = bind_interdomain_evtchn_to_irqhandler(
 562                         queue->vif->domid, rx_evtchn, xenvif_rx_interrupt, 0,
 563                         queue->rx_irq_name, queue);
 564                 if (err < 0)
 565                         goto err_tx_unbind;
 566                 queue->rx_irq = err;
 567                 disable_irq(queue->rx_irq);
 568         }
 569
 570         queue->stalled = true;
 571
 572         task = kthread_create(xenvif_kthread_guest_rx,
 573                               (void *)queue, "%s-guest-rx", queue->name);
 574         if (IS_ERR(task)) {
 575                 pr_warn("Could not allocate kthread for %s\n", queue->name);
 576                 err = PTR_ERR(task);
 577                 goto err_rx_unbind;
 578         }
 579         queue->task = task;
 580         get_task_struct(task);
 581
 582         task = kthread_create(xenvif_dealloc_kthread,
 583                               (void *)queue, "%s-dealloc", queue->name);
 584         if (IS_ERR(task)) {
 585                 pr_warn("Could not allocate kthread for %s\n", queue->name);
 586                 err = PTR_ERR(task);
 587                 goto err_rx_unbind;
 588         }
 589         queue->dealloc_task = task;
 590
 591         wake_up_process(queue->task);
 592         wake_up_process(queue->dealloc_task);
 593
 594         return 0;
 595
 596 err_rx_unbind:
 597         unbind_from_irqhandler(queue->rx_irq, queue);
 598         queue->rx_irq = 0;
 599 err_tx_unbind:
 600         unbind_from_irqhandler(queue->tx_irq, queue);
 601         queue->tx_irq = 0;
 602 err_unmap:
 603         xenvif_unmap_frontend_rings(queue);
 604 err:
 605         module_put(THIS_MODULE);
 606         return err;
 607 }
 608
 609 void xenvif_carrier_off(struct xenvif *vif)
 610 {
 611         struct net_device *dev = vif->dev;
 612
 613         rtnl_lock();
 614         if (test_and_clear_bit(VIF_STATUS_CONNECTED, &vif->status)) {
 615                 netif_carrier_off(dev); /* discard queued packets */
 616                 if (netif_running(dev))
 617                         xenvif_down(vif);
 618         }
 619         rtnl_unlock();
 620 }
 621
 622 void xenvif_disconnect(struct xenvif *vif)
 623 {
 624         struct xenvif_queue *queue = NULL;
 625         unsigned int num_queues = vif->num_queues;
 626         unsigned int queue_index;
 627
 628         xenvif_carrier_off(vif);
 629
 630         for (queue_index = 0; queue_index < num_queues; ++queue_index) {
 631                 queue = &vif->queues[queue_index];
 632
 633                 netif_napi_del(&queue->napi);
 634
 635                 if (queue->task) {
 636                         kthread_stop(queue->task);
 637                         put_task_struct(queue->task);
 638                         queue->task = NULL;
 639                 }
 640
 641                 if (queue->dealloc_task) {
 642                         kthread_stop(queue->dealloc_task);
 643                         queue->dealloc_task = NULL;
 644                 }
 645
 646                 if (queue->tx_irq) {
 647                         if (queue->tx_irq == queue->rx_irq)
 648                                 unbind_from_irqhandler(queue->tx_irq, queue);
 649                         else {
 650                                 unbind_from_irqhandler(queue->tx_irq, queue);
 651                                 unbind_from_irqhandler(queue->rx_irq, queue);
 652                         }
 653                         queue->tx_irq = 0;
 654                 }
 655
 656                 xenvif_unmap_frontend_rings(queue);
 657         }
 658 }
 659
 660 /* Reverse the relevant parts of xenvif_init_queue().
 661  * Used for queue teardown from xenvif_free(), and on the
 662  * error handling paths in xenbus.c:connect().
 663  */
 664 void xenvif_deinit_queue(struct xenvif_queue *queue)
 665 {
 666         gnttab_free_pages(MAX_PENDING_REQS, queue->mmap_pages);
 667 }
 668
 669 void xenvif_free(struct xenvif *vif)
 670 {
 671         struct xenvif_queue *queue = NULL;
 672         unsigned int num_queues = vif->num_queues;
 673         unsigned int queue_index;
 674
 675         unregister_netdev(vif->dev);
 676
 677         for (queue_index = 0; queue_index < num_queues; ++queue_index) {
 678                 queue = &vif->queues[queue_index];
 679                 xenvif_deinit_queue(queue);
 680         }
 681
 682         vfree(vif->queues);
 683         vif->queues = NULL;
 684         vif->num_queues = 0;
 685
 686         free_netdev(vif->dev);
 687
 688         module_put(THIS_MODULE);
 689 }