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         /* Wake the dealloc thread _after_ decrementing inflight_packets so
  66          * that if kthread_stop() has already been called, the dealloc thread
  67          * does not wait forever with nothing to wake it.
  68          */
  69         wake_up(&queue->dealloc_wq);
  70 }
  71
  72 int xenvif_schedulable(struct xenvif *vif)
  73 {
  74         return netif_running(vif->dev) &&
  75                 test_bit(VIF_STATUS_CONNECTED, &vif->status) &&
  76                 !vif->disabled;
  77 }
  78
  79 static irqreturn_t xenvif_tx_interrupt(int irq, void *dev_id)
  80 {
  81         struct xenvif_queue *queue = dev_id;
  82
  83         if (RING_HAS_UNCONSUMED_REQUESTS(&queue->tx))
  84                 napi_schedule(&queue->napi);
  85
  86         return IRQ_HANDLED;
  87 }
  88
  89 static int xenvif_poll(struct napi_struct *napi, int budget)
  90 {
  91         struct xenvif_queue *queue =
  92                 container_of(napi, struct xenvif_queue, napi);
  93         int work_done;
  94
  95         /* This vif is rogue, we pretend we've there is nothing to do
  96          * for this vif to deschedule it from NAPI. But this interface
  97          * will be turned off in thread context later.
  98          */
  99         if (unlikely(queue->vif->disabled)) {
 100                 napi_complete(napi);
 101                 return 0;
 102         }
 103
 104         work_done = xenvif_tx_action(queue, budget);
 105
 106         if (work_done < budget) {
 107                 napi_complete(napi);
 108                 xenvif_napi_schedule_or_enable_events(queue);
 109         }
 110
 111         return work_done;
 112 }
 113
 114 static irqreturn_t xenvif_rx_interrupt(int irq, void *dev_id)
 115 {
 116         struct xenvif_queue *queue = dev_id;
 117
 118         xenvif_kick_thread(queue);
 119
 120         return IRQ_HANDLED;
 121 }
 122
 123 irqreturn_t xenvif_interrupt(int irq, void *dev_id)
 124 {
 125         xenvif_tx_interrupt(irq, dev_id);
 126         xenvif_rx_interrupt(irq, dev_id);
 127
 128         return IRQ_HANDLED;
 129 }
 130
 131 int xenvif_queue_stopped(struct xenvif_queue *queue)
 132 {
 133         struct net_device *dev = queue->vif->dev;
 134         unsigned int id = queue->id;
 135         return netif_tx_queue_stopped(netdev_get_tx_queue(dev, id));
 136 }
 137
 138 void xenvif_wake_queue(struct xenvif_queue *queue)
 139 {
 140         struct net_device *dev = queue->vif->dev;
 141         unsigned int id = queue->id;
 142         netif_tx_wake_queue(netdev_get_tx_queue(dev, id));
 143 }
 144
 145 static int xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev)
 146 {
 147         struct xenvif *vif = netdev_priv(dev);
 148         struct xenvif_queue *queue = NULL;
 149         unsigned int num_queues = vif->num_queues;
 150         u16 index;
 151         struct xenvif_rx_cb *cb;
 152
 153         BUG_ON(skb->dev != dev);
 154
 155         /* Drop the packet if queues are not set up */
 156         if (num_queues < 1)
 157                 goto drop;
 158
 159         /* Obtain the queue to be used to transmit this packet */
 160         index = skb_get_queue_mapping(skb);
 161         if (index >= num_queues) {
 162                 pr_warn_ratelimited("Invalid queue %hu for packet on interface %s\n.",
 163                                     index, vif->dev->name);
 164                 index %= num_queues;
 165         }
 166         queue = &vif->queues[index];
 167
 168         /* Drop the packet if queue is not ready */
 169         if (queue->task == NULL ||
 170             queue->dealloc_task == NULL ||
 171             !xenvif_schedulable(vif))
 172                 goto drop;
 173
 174         if (vif->multicast_control && skb->pkt_type == PACKET_MULTICAST) {
 175                 struct ethhdr *eth = (struct ethhdr *)skb->data;
 176
 177                 if (!xenvif_mcast_match(vif, eth->h_dest))
 178                         goto drop;
 179         }
 180
 181         cb = XENVIF_RX_CB(skb);
 182         cb->expires = jiffies + vif->drain_timeout;
 183
 184         xenvif_rx_queue_tail(queue, skb);
 185         xenvif_kick_thread(queue);
 186
 187         return NETDEV_TX_OK;
 188
 189  drop:
 190         vif->dev->stats.tx_dropped++;
 191         dev_kfree_skb(skb);
 192         return NETDEV_TX_OK;
 193 }
 194
 195 static struct net_device_stats *xenvif_get_stats(struct net_device *dev)
 196 {
 197         struct xenvif *vif = netdev_priv(dev);
 198         struct xenvif_queue *queue = NULL;
 199         unsigned int num_queues = vif->num_queues;
 200         unsigned long rx_bytes = 0;
 201         unsigned long rx_packets = 0;
 202         unsigned long tx_bytes = 0;
 203         unsigned long tx_packets = 0;
 204         unsigned int index;
 205
 206         if (vif->queues == NULL)
 207                 goto out;
 208
 209         /* Aggregate tx and rx stats from each queue */
 210         for (index = 0; index < num_queues; ++index) {
 211                 queue = &vif->queues[index];
 212                 rx_bytes += queue->stats.rx_bytes;
 213                 rx_packets += queue->stats.rx_packets;
 214                 tx_bytes += queue->stats.tx_bytes;
 215                 tx_packets += queue->stats.tx_packets;
 216         }
 217
 218 out:
 219         vif->dev->stats.rx_bytes = rx_bytes;
 220         vif->dev->stats.rx_packets = rx_packets;
 221         vif->dev->stats.tx_bytes = tx_bytes;
 222         vif->dev->stats.tx_packets = tx_packets;
 223
 224         return &vif->dev->stats;
 225 }
 226
 227 static void xenvif_up(struct xenvif *vif)
 228 {
 229         struct xenvif_queue *queue = NULL;
 230         unsigned int num_queues = vif->num_queues;
 231         unsigned int queue_index;
 232
 233         for (queue_index = 0; queue_index < num_queues; ++queue_index) {
 234                 queue = &vif->queues[queue_index];
 235                 napi_enable(&queue->napi);
 236                 enable_irq(queue->tx_irq);
 237                 if (queue->tx_irq != queue->rx_irq)
 238                         enable_irq(queue->rx_irq);
 239                 xenvif_napi_schedule_or_enable_events(queue);
 240         }
 241 }
 242
 243 static void xenvif_down(struct xenvif *vif)
 244 {
 245         struct xenvif_queue *queue = NULL;
 246         unsigned int num_queues = vif->num_queues;
 247         unsigned int queue_index;
 248
 249         for (queue_index = 0; queue_index < num_queues; ++queue_index) {
 250                 queue = &vif->queues[queue_index];
 251                 disable_irq(queue->tx_irq);
 252                 if (queue->tx_irq != queue->rx_irq)
 253                         disable_irq(queue->rx_irq);
 254                 napi_disable(&queue->napi);
 255                 del_timer_sync(&queue->credit_timeout);
 256         }
 257 }
 258
 259 static int xenvif_open(struct net_device *dev)
 260 {
 261         struct xenvif *vif = netdev_priv(dev);
 262         if (test_bit(VIF_STATUS_CONNECTED, &vif->status))
 263                 xenvif_up(vif);
 264         netif_tx_start_all_queues(dev);
 265         return 0;
 266 }
 267
 268 static int xenvif_close(struct net_device *dev)
 269 {
 270         struct xenvif *vif = netdev_priv(dev);
 271         if (test_bit(VIF_STATUS_CONNECTED, &vif->status))
 272                 xenvif_down(vif);
 273         netif_tx_stop_all_queues(dev);
 274         return 0;
 275 }
 276
 277 static int xenvif_change_mtu(struct net_device *dev, int mtu)
 278 {
 279         struct xenvif *vif = netdev_priv(dev);
 280         int max = vif->can_sg ? 65535 - VLAN_ETH_HLEN : ETH_DATA_LEN;
 281
 282         if (mtu > max)
 283                 return -EINVAL;
 284         dev->mtu = mtu;
 285         return 0;
 286 }
 287
 288 static netdev_features_t xenvif_fix_features(struct net_device *dev,
 289         netdev_features_t features)
 290 {
 291         struct xenvif *vif = netdev_priv(dev);
 292
 293         if (!vif->can_sg)
 294                 features &= ~NETIF_F_SG;
 295         if (~(vif->gso_mask | vif->gso_prefix_mask) & GSO_BIT(TCPV4))
 296                 features &= ~NETIF_F_TSO;
 297         if (~(vif->gso_mask | vif->gso_prefix_mask) & GSO_BIT(TCPV6))
 298                 features &= ~NETIF_F_TSO6;
 299         if (!vif->ip_csum)
 300                 features &= ~NETIF_F_IP_CSUM;
 301         if (!vif->ipv6_csum)
 302                 features &= ~NETIF_F_IPV6_CSUM;
 303
 304         return features;
 305 }
 306
 307 static const struct xenvif_stat {
 308         char name[ETH_GSTRING_LEN];
 309         u16 offset;
 310 } xenvif_stats[] = {
 311         {
 312                 "rx_gso_checksum_fixup",
 313                 offsetof(struct xenvif_stats, rx_gso_checksum_fixup)
 314         },
 315         /* If (sent != success + fail), there are probably packets never
 316          * freed up properly!
 317          */
 318         {
 319                 "tx_zerocopy_sent",
 320                 offsetof(struct xenvif_stats, tx_zerocopy_sent),
 321         },
 322         {
 323                 "tx_zerocopy_success",
 324                 offsetof(struct xenvif_stats, tx_zerocopy_success),
 325         },
 326         {
 327                 "tx_zerocopy_fail",
 328                 offsetof(struct xenvif_stats, tx_zerocopy_fail)
 329         },
 330         /* Number of packets exceeding MAX_SKB_FRAG slots. You should use
 331          * a guest with the same MAX_SKB_FRAG
 332          */
 333         {
 334                 "tx_frag_overflow",
 335                 offsetof(struct xenvif_stats, tx_frag_overflow)
 336         },
 337 };
 338
 339 static int xenvif_get_sset_count(struct net_device *dev, int string_set)
 340 {
 341         switch (string_set) {
 342         case ETH_SS_STATS:
 343                 return ARRAY_SIZE(xenvif_stats);
 344         default:
 345                 return -EINVAL;
 346         }
 347 }
 348
 349 static void xenvif_get_ethtool_stats(struct net_device *dev,
 350                                      struct ethtool_stats *stats, u64 * data)
 351 {
 352         struct xenvif *vif = netdev_priv(dev);
 353         unsigned int num_queues = vif->num_queues;
 354         int i;
 355         unsigned int queue_index;
 356
 357         for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++) {
 358                 unsigned long accum = 0;
 359                 for (queue_index = 0; queue_index < num_queues; ++queue_index) {
 360                         void *vif_stats = &vif->queues[queue_index].stats;
 361                         accum += *(unsigned long *)(vif_stats + xenvif_stats[i].offset);
 362                 }
 363                 data[i] = accum;
 364         }
 365 }
 366
 367 static void xenvif_get_strings(struct net_device *dev, u32 stringset, u8 * data)
 368 {
 369         int i;
 370
 371         switch (stringset) {
 372         case ETH_SS_STATS:
 373                 for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++)
 374                         memcpy(data + i * ETH_GSTRING_LEN,
 375                                xenvif_stats[i].name, ETH_GSTRING_LEN);
 376                 break;
 377         }
 378 }
 379
 380 static const struct ethtool_ops xenvif_ethtool_ops = {
 381         .get_link       = ethtool_op_get_link,
 382
 383         .get_sset_count = xenvif_get_sset_count,
 384         .get_ethtool_stats = xenvif_get_ethtool_stats,
 385         .get_strings = xenvif_get_strings,
 386 };
 387
 388 static const struct net_device_ops xenvif_netdev_ops = {
 389         .ndo_start_xmit = xenvif_start_xmit,
 390         .ndo_get_stats  = xenvif_get_stats,
 391         .ndo_open       = xenvif_open,
 392         .ndo_stop       = xenvif_close,
 393         .ndo_change_mtu = xenvif_change_mtu,
 394         .ndo_fix_features = xenvif_fix_features,
 395         .ndo_set_mac_address = eth_mac_addr,
 396         .ndo_validate_addr   = eth_validate_addr,
 397 };
 398
 399 struct xenvif *xenvif_alloc(struct device *parent, domid_t domid,
 400                             unsigned int handle)
 401 {
 402         int err;
 403         struct net_device *dev;
 404         struct xenvif *vif;
 405         char name[IFNAMSIZ] = {};
 406
 407         snprintf(name, IFNAMSIZ - 1, "vif%u.%u", domid, handle);
 408         /* Allocate a netdev with the max. supported number of queues.
 409          * When the guest selects the desired number, it will be updated
 410          * via netif_set_real_num_*_queues().
 411          */
 412         dev = alloc_netdev_mq(sizeof(struct xenvif), name, NET_NAME_UNKNOWN,
 413                               ether_setup, xenvif_max_queues);
 414         if (dev == NULL) {
 415                 pr_warn("Could not allocate netdev for %s\n", name);
 416                 return ERR_PTR(-ENOMEM);
 417         }
 418
 419         SET_NETDEV_DEV(dev, parent);
 420
 421         vif = netdev_priv(dev);
 422
 423         vif->domid  = domid;
 424         vif->handle = handle;
 425         vif->can_sg = 1;
 426         vif->ip_csum = 1;
 427         vif->dev = dev;
 428         vif->disabled = false;
 429         vif->drain_timeout = msecs_to_jiffies(rx_drain_timeout_msecs);
 430         vif->stall_timeout = msecs_to_jiffies(rx_stall_timeout_msecs);
 431
 432         /* Start out with no queues. */
 433         vif->queues = NULL;
 434         vif->num_queues = 0;
 435
 436         spin_lock_init(&vif->lock);
 437         INIT_LIST_HEAD(&vif->fe_mcast_addr);
 438
 439         dev->netdev_ops = &xenvif_netdev_ops;
 440         dev->hw_features = NETIF_F_SG |
 441                 NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM |
 442                 NETIF_F_TSO | NETIF_F_TSO6;
 443         dev->features = dev->hw_features | NETIF_F_RXCSUM;
 444         dev->ethtool_ops = &xenvif_ethtool_ops;
 445
 446         dev->tx_queue_len = XENVIF_QUEUE_LENGTH;
 447
 448         /*
 449          * Initialise a dummy MAC address. We choose the numerically
 450          * largest non-broadcast address to prevent the address getting
 451          * stolen by an Ethernet bridge for STP purposes.
 452          * (FE:FF:FF:FF:FF:FF)
 453          */
 454         eth_broadcast_addr(dev->dev_addr);
 455         dev->dev_addr[0] &= ~0x01;
 456
 457         netif_carrier_off(dev);
 458
 459         err = register_netdev(dev);
 460         if (err) {
 461                 netdev_warn(dev, "Could not register device: err=%d\n", err);
 462                 free_netdev(dev);
 463                 return ERR_PTR(err);
 464         }
 465
 466         netdev_dbg(dev, "Successfully created xenvif\n");
 467
 468         __module_get(THIS_MODULE);
 469
 470         return vif;
 471 }
 472
 473 int xenvif_init_queue(struct xenvif_queue *queue)
 474 {
 475         int err, i;
 476
 477         queue->credit_bytes = queue->remaining_credit = ~0UL;
 478         queue->credit_usec  = 0UL;
 479         init_timer(&queue->credit_timeout);
 480         queue->credit_timeout.function = xenvif_tx_credit_callback;
 481         queue->credit_window_start = get_jiffies_64();
 482
 483         queue->rx_queue_max = XENVIF_RX_QUEUE_BYTES;
 484
 485         skb_queue_head_init(&queue->rx_queue);
 486         skb_queue_head_init(&queue->tx_queue);
 487
 488         queue->pending_cons = 0;
 489         queue->pending_prod = MAX_PENDING_REQS;
 490         for (i = 0; i < MAX_PENDING_REQS; ++i)
 491                 queue->pending_ring[i] = i;
 492
 493         spin_lock_init(&queue->callback_lock);
 494         spin_lock_init(&queue->response_lock);
 495
 496         /* If ballooning is disabled, this will consume real memory, so you
 497          * better enable it. The long term solution would be to use just a
 498          * bunch of valid page descriptors, without dependency on ballooning
 499          */
 500         err = gnttab_alloc_pages(MAX_PENDING_REQS,
 501                                  queue->mmap_pages);
 502         if (err) {
 503                 netdev_err(queue->vif->dev, "Could not reserve mmap_pages\n");
 504                 return -ENOMEM;
 505         }
 506
 507         for (i = 0; i < MAX_PENDING_REQS; i++) {
 508                 queue->pending_tx_info[i].callback_struct = (struct ubuf_info)
 509                         { .callback = xenvif_zerocopy_callback,
 510                           .ctx = NULL,
 511                           .desc = i };
 512                 queue->grant_tx_handle[i] = NETBACK_INVALID_HANDLE;
 513         }
 514
 515         return 0;
 516 }
 517
 518 void xenvif_carrier_on(struct xenvif *vif)
 519 {
 520         rtnl_lock();
 521         if (!vif->can_sg && vif->dev->mtu > ETH_DATA_LEN)
 522                 dev_set_mtu(vif->dev, ETH_DATA_LEN);
 523         netdev_update_features(vif->dev);
 524         set_bit(VIF_STATUS_CONNECTED, &vif->status);
 525         if (netif_running(vif->dev))
 526                 xenvif_up(vif);
 527         rtnl_unlock();
 528 }
 529
 530 int xenvif_connect(struct xenvif_queue *queue, unsigned long tx_ring_ref,
 531                    unsigned long rx_ring_ref, unsigned int tx_evtchn,
 532                    unsigned int rx_evtchn)
 533 {
 534         struct task_struct *task;
 535         int err = -ENOMEM;
 536
 537         BUG_ON(queue->tx_irq);
 538         BUG_ON(queue->task);
 539         BUG_ON(queue->dealloc_task);
 540
 541         err = xenvif_map_frontend_rings(queue, tx_ring_ref, rx_ring_ref);
 542         if (err < 0)
 543                 goto err;
 544
 545         init_waitqueue_head(&queue->wq);
 546         init_waitqueue_head(&queue->dealloc_wq);
 547         atomic_set(&queue->inflight_packets, 0);
 548
 549         netif_napi_add(queue->vif->dev, &queue->napi, xenvif_poll,
 550                         XENVIF_NAPI_WEIGHT);
 551
 552         if (tx_evtchn == rx_evtchn) {
 553                 /* feature-split-event-channels == 0 */
 554                 err = bind_interdomain_evtchn_to_irqhandler(
 555                         queue->vif->domid, tx_evtchn, xenvif_interrupt, 0,
 556                         queue->name, queue);
 557                 if (err < 0)
 558                         goto err_unmap;
 559                 queue->tx_irq = queue->rx_irq = err;
 560                 disable_irq(queue->tx_irq);
 561         } else {
 562                 /* feature-split-event-channels == 1 */
 563                 snprintf(queue->tx_irq_name, sizeof(queue->tx_irq_name),
 564                          "%s-tx", queue->name);
 565                 err = bind_interdomain_evtchn_to_irqhandler(
 566                         queue->vif->domid, tx_evtchn, xenvif_tx_interrupt, 0,
 567                         queue->tx_irq_name, queue);
 568                 if (err < 0)
 569                         goto err_unmap;
 570                 queue->tx_irq = err;
 571                 disable_irq(queue->tx_irq);
 572
 573                 snprintf(queue->rx_irq_name, sizeof(queue->rx_irq_name),
 574                          "%s-rx", queue->name);
 575                 err = bind_interdomain_evtchn_to_irqhandler(
 576                         queue->vif->domid, rx_evtchn, xenvif_rx_interrupt, 0,
 577                         queue->rx_irq_name, queue);
 578                 if (err < 0)
 579                         goto err_tx_unbind;
 580                 queue->rx_irq = err;
 581                 disable_irq(queue->rx_irq);
 582         }
 583
 584         queue->stalled = true;
 585
 586         task = kthread_create(xenvif_kthread_guest_rx,
 587                               (void *)queue, "%s-guest-rx", queue->name);
 588         if (IS_ERR(task)) {
 589                 pr_warn("Could not allocate kthread for %s\n", queue->name);
 590                 err = PTR_ERR(task);
 591                 goto err_rx_unbind;
 592         }
 593         queue->task = task;
 594         get_task_struct(task);
 595
 596         task = kthread_create(xenvif_dealloc_kthread,
 597                               (void *)queue, "%s-dealloc", queue->name);
 598         if (IS_ERR(task)) {
 599                 pr_warn("Could not allocate kthread for %s\n", queue->name);
 600                 err = PTR_ERR(task);
 601                 goto err_rx_unbind;
 602         }
 603         queue->dealloc_task = task;
 604
 605         wake_up_process(queue->task);
 606         wake_up_process(queue->dealloc_task);
 607
 608         return 0;
 609
 610 err_rx_unbind:
 611         unbind_from_irqhandler(queue->rx_irq, queue);
 612         queue->rx_irq = 0;
 613 err_tx_unbind:
 614         unbind_from_irqhandler(queue->tx_irq, queue);
 615         queue->tx_irq = 0;
 616 err_unmap:
 617         xenvif_unmap_frontend_rings(queue);
 618 err:
 619         module_put(THIS_MODULE);
 620         return err;
 621 }
 622
 623 void xenvif_carrier_off(struct xenvif *vif)
 624 {
 625         struct net_device *dev = vif->dev;
 626
 627         rtnl_lock();
 628         if (test_and_clear_bit(VIF_STATUS_CONNECTED, &vif->status)) {
 629                 netif_carrier_off(dev); /* discard queued packets */
 630                 if (netif_running(dev))
 631                         xenvif_down(vif);
 632         }
 633         rtnl_unlock();
 634 }
 635
 636 void xenvif_disconnect(struct xenvif *vif)
 637 {
 638         struct xenvif_queue *queue = NULL;
 639         unsigned int num_queues = vif->num_queues;
 640         unsigned int queue_index;
 641
 642         xenvif_carrier_off(vif);
 643
 644         for (queue_index = 0; queue_index < num_queues; ++queue_index) {
 645                 queue = &vif->queues[queue_index];
 646
 647                 netif_napi_del(&queue->napi);
 648
 649                 if (queue->task) {
 650                         kthread_stop(queue->task);
 651                         put_task_struct(queue->task);
 652                         queue->task = NULL;
 653                 }
 654
 655                 if (queue->dealloc_task) {
 656                         kthread_stop(queue->dealloc_task);
 657                         queue->dealloc_task = NULL;
 658                 }
 659
 660                 if (queue->tx_irq) {
 661                         if (queue->tx_irq == queue->rx_irq)
 662                                 unbind_from_irqhandler(queue->tx_irq, queue);
 663                         else {
 664                                 unbind_from_irqhandler(queue->tx_irq, queue);
 665                                 unbind_from_irqhandler(queue->rx_irq, queue);
 666                         }
 667                         queue->tx_irq = 0;
 668                 }
 669
 670                 xenvif_unmap_frontend_rings(queue);
 671         }
 672
 673         xenvif_mcast_addr_list_free(vif);
 674 }
 675
 676 /* Reverse the relevant parts of xenvif_init_queue().
 677  * Used for queue teardown from xenvif_free(), and on the
 678  * error handling paths in xenbus.c:connect().
 679  */
 680 void xenvif_deinit_queue(struct xenvif_queue *queue)
 681 {
 682         gnttab_free_pages(MAX_PENDING_REQS, queue->mmap_pages);
 683 }
 684
 685 void xenvif_free(struct xenvif *vif)
 686 {
 687         struct xenvif_queue *queue = NULL;
 688         unsigned int num_queues = vif->num_queues;
 689         unsigned int queue_index;
 690
 691         unregister_netdev(vif->dev);
 692
 693         for (queue_index = 0; queue_index < num_queues; ++queue_index) {
 694                 queue = &vif->queues[queue_index];
 695                 xenvif_deinit_queue(queue);
 696         }
 697
 698         vfree(vif->queues);
 699         vif->queues = NULL;
 700         vif->num_queues = 0;
 701
 702         free_netdev(vif->dev);
 703
 704         module_put(THIS_MODULE);
 705 }