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/sched/task.h> 35 #include <linux/ethtool.h> 36 #include <linux/rtnetlink.h> 37 #include <linux/if_vlan.h> 38 #include <linux/vmalloc.h> 39 40 #include <xen/events.h> 41 #include <asm/xen/hypercall.h> 42 #include <xen/balloon.h> 43 44 #define XENVIF_QUEUE_LENGTH 32 45 #define XENVIF_NAPI_WEIGHT 64 46 47 /* Number of bytes allowed on the internal guest Rx queue. */ 48 #define XENVIF_RX_QUEUE_BYTES (XEN_NETIF_RX_RING_SIZE/2 * PAGE_SIZE) 49 50 /* This function is used to set SKBTX_DEV_ZEROCOPY as well as 51 * increasing the inflight counter. We need to increase the inflight 52 * counter because core driver calls into xenvif_zerocopy_callback 53 * which calls xenvif_skb_zerocopy_complete. 54 */ 55 void xenvif_skb_zerocopy_prepare(struct xenvif_queue *queue, 56 struct sk_buff *skb) 57 { 58 skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY; 59 atomic_inc(&queue->inflight_packets); 60 } 61 62 void xenvif_skb_zerocopy_complete(struct xenvif_queue *queue) 63 { 64 atomic_dec(&queue->inflight_packets); 65 66 /* Wake the dealloc thread _after_ decrementing inflight_packets so 67 * that if kthread_stop() has already been called, the dealloc thread 68 * does not wait forever with nothing to wake it. 69 */ 70 wake_up(&queue->dealloc_wq); 71 } 72 73 int xenvif_schedulable(struct xenvif *vif) 74 { 75 return netif_running(vif->dev) && 76 test_bit(VIF_STATUS_CONNECTED, &vif->status) && 77 !vif->disabled; 78 } 79 80 static irqreturn_t xenvif_tx_interrupt(int irq, void *dev_id) 81 { 82 struct xenvif_queue *queue = dev_id; 83 84 if (RING_HAS_UNCONSUMED_REQUESTS(&queue->tx)) 85 napi_schedule(&queue->napi); 86 87 return IRQ_HANDLED; 88 } 89 90 static int xenvif_poll(struct napi_struct *napi, int budget) 91 { 92 struct xenvif_queue *queue = 93 container_of(napi, struct xenvif_queue, napi); 94 int work_done; 95 96 /* This vif is rogue, we pretend we've there is nothing to do 97 * for this vif to deschedule it from NAPI. But this interface 98 * will be turned off in thread context later. 99 */ 100 if (unlikely(queue->vif->disabled)) { 101 napi_complete(napi); 102 return 0; 103 } 104 105 work_done = xenvif_tx_action(queue, budget); 106 107 if (work_done < budget) { 108 napi_complete_done(napi, work_done); 109 xenvif_napi_schedule_or_enable_events(queue); 110 } 111 112 return work_done; 113 } 114 115 static irqreturn_t xenvif_rx_interrupt(int irq, void *dev_id) 116 { 117 struct xenvif_queue *queue = dev_id; 118 119 xenvif_kick_thread(queue); 120 121 return IRQ_HANDLED; 122 } 123 124 irqreturn_t xenvif_interrupt(int irq, void *dev_id) 125 { 126 xenvif_tx_interrupt(irq, dev_id); 127 xenvif_rx_interrupt(irq, dev_id); 128 129 return IRQ_HANDLED; 130 } 131 132 int xenvif_queue_stopped(struct xenvif_queue *queue) 133 { 134 struct net_device *dev = queue->vif->dev; 135 unsigned int id = queue->id; 136 return netif_tx_queue_stopped(netdev_get_tx_queue(dev, id)); 137 } 138 139 void xenvif_wake_queue(struct xenvif_queue *queue) 140 { 141 struct net_device *dev = queue->vif->dev; 142 unsigned int id = queue->id; 143 netif_tx_wake_queue(netdev_get_tx_queue(dev, id)); 144 } 145 146 static u16 xenvif_select_queue(struct net_device *dev, struct sk_buff *skb, 147 void *accel_priv, 148 select_queue_fallback_t fallback) 149 { 150 struct xenvif *vif = netdev_priv(dev); 151 unsigned int size = vif->hash.size; 152 153 if (vif->hash.alg == XEN_NETIF_CTRL_HASH_ALGORITHM_NONE) 154 return fallback(dev, skb) % dev->real_num_tx_queues; 155 156 xenvif_set_skb_hash(vif, skb); 157 158 if (size == 0) 159 return skb_get_hash_raw(skb) % dev->real_num_tx_queues; 160 161 return vif->hash.mapping[skb_get_hash_raw(skb) % size]; 162 } 163 164 static int xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev) 165 { 166 struct xenvif *vif = netdev_priv(dev); 167 struct xenvif_queue *queue = NULL; 168 unsigned int num_queues; 169 u16 index; 170 struct xenvif_rx_cb *cb; 171 172 BUG_ON(skb->dev != dev); 173 174 /* Drop the packet if queues are not set up. 175 * This handler should be called inside an RCU read section 176 * so we don't need to enter it here explicitly. 177 */ 178 num_queues = READ_ONCE(vif->num_queues); 179 if (num_queues < 1) 180 goto drop; 181 182 /* Obtain the queue to be used to transmit this packet */ 183 index = skb_get_queue_mapping(skb); 184 if (index >= num_queues) { 185 pr_warn_ratelimited("Invalid queue %hu for packet on interface %s\n.", 186 index, vif->dev->name); 187 index %= num_queues; 188 } 189 queue = &vif->queues[index]; 190 191 /* Drop the packet if queue is not ready */ 192 if (queue->task == NULL || 193 queue->dealloc_task == NULL || 194 !xenvif_schedulable(vif)) 195 goto drop; 196 197 if (vif->multicast_control && skb->pkt_type == PACKET_MULTICAST) { 198 struct ethhdr *eth = (struct ethhdr *)skb->data; 199 200 if (!xenvif_mcast_match(vif, eth->h_dest)) 201 goto drop; 202 } 203 204 cb = XENVIF_RX_CB(skb); 205 cb->expires = jiffies + vif->drain_timeout; 206 207 /* If there is no hash algorithm configured then make sure there 208 * is no hash information in the socket buffer otherwise it 209 * would be incorrectly forwarded to the frontend. 210 */ 211 if (vif->hash.alg == XEN_NETIF_CTRL_HASH_ALGORITHM_NONE) 212 skb_clear_hash(skb); 213 214 xenvif_rx_queue_tail(queue, skb); 215 xenvif_kick_thread(queue); 216 217 return NETDEV_TX_OK; 218 219 drop: 220 vif->dev->stats.tx_dropped++; 221 dev_kfree_skb(skb); 222 return NETDEV_TX_OK; 223 } 224 225 static struct net_device_stats *xenvif_get_stats(struct net_device *dev) 226 { 227 struct xenvif *vif = netdev_priv(dev); 228 struct xenvif_queue *queue = NULL; 229 unsigned int num_queues; 230 u64 rx_bytes = 0; 231 u64 rx_packets = 0; 232 u64 tx_bytes = 0; 233 u64 tx_packets = 0; 234 unsigned int index; 235 236 rcu_read_lock(); 237 num_queues = READ_ONCE(vif->num_queues); 238 239 /* Aggregate tx and rx stats from each queue */ 240 for (index = 0; index < num_queues; ++index) { 241 queue = &vif->queues[index]; 242 rx_bytes += queue->stats.rx_bytes; 243 rx_packets += queue->stats.rx_packets; 244 tx_bytes += queue->stats.tx_bytes; 245 tx_packets += queue->stats.tx_packets; 246 } 247 248 rcu_read_unlock(); 249 250 vif->dev->stats.rx_bytes = rx_bytes; 251 vif->dev->stats.rx_packets = rx_packets; 252 vif->dev->stats.tx_bytes = tx_bytes; 253 vif->dev->stats.tx_packets = tx_packets; 254 255 return &vif->dev->stats; 256 } 257 258 static void xenvif_up(struct xenvif *vif) 259 { 260 struct xenvif_queue *queue = NULL; 261 unsigned int num_queues = vif->num_queues; 262 unsigned int queue_index; 263 264 for (queue_index = 0; queue_index < num_queues; ++queue_index) { 265 queue = &vif->queues[queue_index]; 266 napi_enable(&queue->napi); 267 enable_irq(queue->tx_irq); 268 if (queue->tx_irq != queue->rx_irq) 269 enable_irq(queue->rx_irq); 270 xenvif_napi_schedule_or_enable_events(queue); 271 } 272 } 273 274 static void xenvif_down(struct xenvif *vif) 275 { 276 struct xenvif_queue *queue = NULL; 277 unsigned int num_queues = vif->num_queues; 278 unsigned int queue_index; 279 280 for (queue_index = 0; queue_index < num_queues; ++queue_index) { 281 queue = &vif->queues[queue_index]; 282 disable_irq(queue->tx_irq); 283 if (queue->tx_irq != queue->rx_irq) 284 disable_irq(queue->rx_irq); 285 napi_disable(&queue->napi); 286 del_timer_sync(&queue->credit_timeout); 287 } 288 } 289 290 static int xenvif_open(struct net_device *dev) 291 { 292 struct xenvif *vif = netdev_priv(dev); 293 if (test_bit(VIF_STATUS_CONNECTED, &vif->status)) 294 xenvif_up(vif); 295 netif_tx_start_all_queues(dev); 296 return 0; 297 } 298 299 static int xenvif_close(struct net_device *dev) 300 { 301 struct xenvif *vif = netdev_priv(dev); 302 if (test_bit(VIF_STATUS_CONNECTED, &vif->status)) 303 xenvif_down(vif); 304 netif_tx_stop_all_queues(dev); 305 return 0; 306 } 307 308 static int xenvif_change_mtu(struct net_device *dev, int mtu) 309 { 310 struct xenvif *vif = netdev_priv(dev); 311 int max = vif->can_sg ? ETH_MAX_MTU - VLAN_ETH_HLEN : ETH_DATA_LEN; 312 313 if (mtu > max) 314 return -EINVAL; 315 dev->mtu = mtu; 316 return 0; 317 } 318 319 static netdev_features_t xenvif_fix_features(struct net_device *dev, 320 netdev_features_t features) 321 { 322 struct xenvif *vif = netdev_priv(dev); 323 324 if (!vif->can_sg) 325 features &= ~NETIF_F_SG; 326 if (~(vif->gso_mask) & GSO_BIT(TCPV4)) 327 features &= ~NETIF_F_TSO; 328 if (~(vif->gso_mask) & GSO_BIT(TCPV6)) 329 features &= ~NETIF_F_TSO6; 330 if (!vif->ip_csum) 331 features &= ~NETIF_F_IP_CSUM; 332 if (!vif->ipv6_csum) 333 features &= ~NETIF_F_IPV6_CSUM; 334 335 return features; 336 } 337 338 static const struct xenvif_stat { 339 char name[ETH_GSTRING_LEN]; 340 u16 offset; 341 } xenvif_stats[] = { 342 { 343 "rx_gso_checksum_fixup", 344 offsetof(struct xenvif_stats, rx_gso_checksum_fixup) 345 }, 346 /* If (sent != success + fail), there are probably packets never 347 * freed up properly! 348 */ 349 { 350 "tx_zerocopy_sent", 351 offsetof(struct xenvif_stats, tx_zerocopy_sent), 352 }, 353 { 354 "tx_zerocopy_success", 355 offsetof(struct xenvif_stats, tx_zerocopy_success), 356 }, 357 { 358 "tx_zerocopy_fail", 359 offsetof(struct xenvif_stats, tx_zerocopy_fail) 360 }, 361 /* Number of packets exceeding MAX_SKB_FRAG slots. You should use 362 * a guest with the same MAX_SKB_FRAG 363 */ 364 { 365 "tx_frag_overflow", 366 offsetof(struct xenvif_stats, tx_frag_overflow) 367 }, 368 }; 369 370 static int xenvif_get_sset_count(struct net_device *dev, int string_set) 371 { 372 switch (string_set) { 373 case ETH_SS_STATS: 374 return ARRAY_SIZE(xenvif_stats); 375 default: 376 return -EINVAL; 377 } 378 } 379 380 static void xenvif_get_ethtool_stats(struct net_device *dev, 381 struct ethtool_stats *stats, u64 * data) 382 { 383 struct xenvif *vif = netdev_priv(dev); 384 unsigned int num_queues; 385 int i; 386 unsigned int queue_index; 387 388 rcu_read_lock(); 389 num_queues = READ_ONCE(vif->num_queues); 390 391 for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++) { 392 unsigned long accum = 0; 393 for (queue_index = 0; queue_index < num_queues; ++queue_index) { 394 void *vif_stats = &vif->queues[queue_index].stats; 395 accum += *(unsigned long *)(vif_stats + xenvif_stats[i].offset); 396 } 397 data[i] = accum; 398 } 399 400 rcu_read_unlock(); 401 } 402 403 static void xenvif_get_strings(struct net_device *dev, u32 stringset, u8 * data) 404 { 405 int i; 406 407 switch (stringset) { 408 case ETH_SS_STATS: 409 for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++) 410 memcpy(data + i * ETH_GSTRING_LEN, 411 xenvif_stats[i].name, ETH_GSTRING_LEN); 412 break; 413 } 414 } 415 416 static const struct ethtool_ops xenvif_ethtool_ops = { 417 .get_link = ethtool_op_get_link, 418 419 .get_sset_count = xenvif_get_sset_count, 420 .get_ethtool_stats = xenvif_get_ethtool_stats, 421 .get_strings = xenvif_get_strings, 422 }; 423 424 static const struct net_device_ops xenvif_netdev_ops = { 425 .ndo_select_queue = xenvif_select_queue, 426 .ndo_start_xmit = xenvif_start_xmit, 427 .ndo_get_stats = xenvif_get_stats, 428 .ndo_open = xenvif_open, 429 .ndo_stop = xenvif_close, 430 .ndo_change_mtu = xenvif_change_mtu, 431 .ndo_fix_features = xenvif_fix_features, 432 .ndo_set_mac_address = eth_mac_addr, 433 .ndo_validate_addr = eth_validate_addr, 434 }; 435 436 struct xenvif *xenvif_alloc(struct device *parent, domid_t domid, 437 unsigned int handle) 438 { 439 int err; 440 struct net_device *dev; 441 struct xenvif *vif; 442 char name[IFNAMSIZ] = {}; 443 444 snprintf(name, IFNAMSIZ - 1, "vif%u.%u", domid, handle); 445 /* Allocate a netdev with the max. supported number of queues. 446 * When the guest selects the desired number, it will be updated 447 * via netif_set_real_num_*_queues(). 448 */ 449 dev = alloc_netdev_mq(sizeof(struct xenvif), name, NET_NAME_UNKNOWN, 450 ether_setup, xenvif_max_queues); 451 if (dev == NULL) { 452 pr_warn("Could not allocate netdev for %s\n", name); 453 return ERR_PTR(-ENOMEM); 454 } 455 456 SET_NETDEV_DEV(dev, parent); 457 458 vif = netdev_priv(dev); 459 460 vif->domid = domid; 461 vif->handle = handle; 462 vif->can_sg = 1; 463 vif->ip_csum = 1; 464 vif->dev = dev; 465 vif->disabled = false; 466 vif->drain_timeout = msecs_to_jiffies(rx_drain_timeout_msecs); 467 vif->stall_timeout = msecs_to_jiffies(rx_stall_timeout_msecs); 468 469 /* Start out with no queues. */ 470 vif->queues = NULL; 471 vif->num_queues = 0; 472 473 spin_lock_init(&vif->lock); 474 INIT_LIST_HEAD(&vif->fe_mcast_addr); 475 476 dev->netdev_ops = &xenvif_netdev_ops; 477 dev->hw_features = NETIF_F_SG | 478 NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM | 479 NETIF_F_TSO | NETIF_F_TSO6 | NETIF_F_FRAGLIST; 480 dev->features = dev->hw_features | NETIF_F_RXCSUM; 481 dev->ethtool_ops = &xenvif_ethtool_ops; 482 483 dev->tx_queue_len = XENVIF_QUEUE_LENGTH; 484 485 dev->min_mtu = 0; 486 dev->max_mtu = ETH_MAX_MTU - VLAN_ETH_HLEN; 487 488 /* 489 * Initialise a dummy MAC address. We choose the numerically 490 * largest non-broadcast address to prevent the address getting 491 * stolen by an Ethernet bridge for STP purposes. 492 * (FE:FF:FF:FF:FF:FF) 493 */ 494 eth_broadcast_addr(dev->dev_addr); 495 dev->dev_addr[0] &= ~0x01; 496 497 netif_carrier_off(dev); 498 499 err = register_netdev(dev); 500 if (err) { 501 netdev_warn(dev, "Could not register device: err=%d\n", err); 502 free_netdev(dev); 503 return ERR_PTR(err); 504 } 505 506 netdev_dbg(dev, "Successfully created xenvif\n"); 507 508 __module_get(THIS_MODULE); 509 510 return vif; 511 } 512 513 int xenvif_init_queue(struct xenvif_queue *queue) 514 { 515 int err, i; 516 517 queue->credit_bytes = queue->remaining_credit = ~0UL; 518 queue->credit_usec = 0UL; 519 init_timer(&queue->credit_timeout); 520 queue->credit_timeout.function = xenvif_tx_credit_callback; 521 queue->credit_window_start = get_jiffies_64(); 522 523 queue->rx_queue_max = XENVIF_RX_QUEUE_BYTES; 524 525 skb_queue_head_init(&queue->rx_queue); 526 skb_queue_head_init(&queue->tx_queue); 527 528 queue->pending_cons = 0; 529 queue->pending_prod = MAX_PENDING_REQS; 530 for (i = 0; i < MAX_PENDING_REQS; ++i) 531 queue->pending_ring[i] = i; 532 533 spin_lock_init(&queue->callback_lock); 534 spin_lock_init(&queue->response_lock); 535 536 /* If ballooning is disabled, this will consume real memory, so you 537 * better enable it. The long term solution would be to use just a 538 * bunch of valid page descriptors, without dependency on ballooning 539 */ 540 err = gnttab_alloc_pages(MAX_PENDING_REQS, 541 queue->mmap_pages); 542 if (err) { 543 netdev_err(queue->vif->dev, "Could not reserve mmap_pages\n"); 544 return -ENOMEM; 545 } 546 547 for (i = 0; i < MAX_PENDING_REQS; i++) { 548 queue->pending_tx_info[i].callback_struct = (struct ubuf_info) 549 { .callback = xenvif_zerocopy_callback, 550 .ctx = NULL, 551 .desc = i }; 552 queue->grant_tx_handle[i] = NETBACK_INVALID_HANDLE; 553 } 554 555 return 0; 556 } 557 558 void xenvif_carrier_on(struct xenvif *vif) 559 { 560 rtnl_lock(); 561 if (!vif->can_sg && vif->dev->mtu > ETH_DATA_LEN) 562 dev_set_mtu(vif->dev, ETH_DATA_LEN); 563 netdev_update_features(vif->dev); 564 set_bit(VIF_STATUS_CONNECTED, &vif->status); 565 if (netif_running(vif->dev)) 566 xenvif_up(vif); 567 rtnl_unlock(); 568 } 569 570 int xenvif_connect_ctrl(struct xenvif *vif, grant_ref_t ring_ref, 571 unsigned int evtchn) 572 { 573 struct net_device *dev = vif->dev; 574 void *addr; 575 struct xen_netif_ctrl_sring *shared; 576 int err; 577 578 err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(vif), 579 &ring_ref, 1, &addr); 580 if (err) 581 goto err; 582 583 shared = (struct xen_netif_ctrl_sring *)addr; 584 BACK_RING_INIT(&vif->ctrl, shared, XEN_PAGE_SIZE); 585 586 err = bind_interdomain_evtchn_to_irq(vif->domid, evtchn); 587 if (err < 0) 588 goto err_unmap; 589 590 vif->ctrl_irq = err; 591 592 xenvif_init_hash(vif); 593 594 err = request_threaded_irq(vif->ctrl_irq, NULL, xenvif_ctrl_irq_fn, 595 IRQF_ONESHOT, "xen-netback-ctrl", vif); 596 if (err) { 597 pr_warn("Could not setup irq handler for %s\n", dev->name); 598 goto err_deinit; 599 } 600 601 return 0; 602 603 err_deinit: 604 xenvif_deinit_hash(vif); 605 unbind_from_irqhandler(vif->ctrl_irq, vif); 606 vif->ctrl_irq = 0; 607 608 err_unmap: 609 xenbus_unmap_ring_vfree(xenvif_to_xenbus_device(vif), 610 vif->ctrl.sring); 611 vif->ctrl.sring = NULL; 612 613 err: 614 return err; 615 } 616 617 int xenvif_connect_data(struct xenvif_queue *queue, 618 unsigned long tx_ring_ref, 619 unsigned long rx_ring_ref, 620 unsigned int tx_evtchn, 621 unsigned int rx_evtchn) 622 { 623 struct task_struct *task; 624 int err = -ENOMEM; 625 626 BUG_ON(queue->tx_irq); 627 BUG_ON(queue->task); 628 BUG_ON(queue->dealloc_task); 629 630 err = xenvif_map_frontend_data_rings(queue, tx_ring_ref, 631 rx_ring_ref); 632 if (err < 0) 633 goto err; 634 635 init_waitqueue_head(&queue->wq); 636 init_waitqueue_head(&queue->dealloc_wq); 637 atomic_set(&queue->inflight_packets, 0); 638 639 netif_napi_add(queue->vif->dev, &queue->napi, xenvif_poll, 640 XENVIF_NAPI_WEIGHT); 641 642 if (tx_evtchn == rx_evtchn) { 643 /* feature-split-event-channels == 0 */ 644 err = bind_interdomain_evtchn_to_irqhandler( 645 queue->vif->domid, tx_evtchn, xenvif_interrupt, 0, 646 queue->name, queue); 647 if (err < 0) 648 goto err_unmap; 649 queue->tx_irq = queue->rx_irq = err; 650 disable_irq(queue->tx_irq); 651 } else { 652 /* feature-split-event-channels == 1 */ 653 snprintf(queue->tx_irq_name, sizeof(queue->tx_irq_name), 654 "%s-tx", queue->name); 655 err = bind_interdomain_evtchn_to_irqhandler( 656 queue->vif->domid, tx_evtchn, xenvif_tx_interrupt, 0, 657 queue->tx_irq_name, queue); 658 if (err < 0) 659 goto err_unmap; 660 queue->tx_irq = err; 661 disable_irq(queue->tx_irq); 662 663 snprintf(queue->rx_irq_name, sizeof(queue->rx_irq_name), 664 "%s-rx", queue->name); 665 err = bind_interdomain_evtchn_to_irqhandler( 666 queue->vif->domid, rx_evtchn, xenvif_rx_interrupt, 0, 667 queue->rx_irq_name, queue); 668 if (err < 0) 669 goto err_tx_unbind; 670 queue->rx_irq = err; 671 disable_irq(queue->rx_irq); 672 } 673 674 queue->stalled = true; 675 676 task = kthread_create(xenvif_kthread_guest_rx, 677 (void *)queue, "%s-guest-rx", queue->name); 678 if (IS_ERR(task)) { 679 pr_warn("Could not allocate kthread for %s\n", queue->name); 680 err = PTR_ERR(task); 681 goto err_rx_unbind; 682 } 683 queue->task = task; 684 get_task_struct(task); 685 686 task = kthread_create(xenvif_dealloc_kthread, 687 (void *)queue, "%s-dealloc", queue->name); 688 if (IS_ERR(task)) { 689 pr_warn("Could not allocate kthread for %s\n", queue->name); 690 err = PTR_ERR(task); 691 goto err_rx_unbind; 692 } 693 queue->dealloc_task = task; 694 695 wake_up_process(queue->task); 696 wake_up_process(queue->dealloc_task); 697 698 return 0; 699 700 err_rx_unbind: 701 unbind_from_irqhandler(queue->rx_irq, queue); 702 queue->rx_irq = 0; 703 err_tx_unbind: 704 unbind_from_irqhandler(queue->tx_irq, queue); 705 queue->tx_irq = 0; 706 err_unmap: 707 xenvif_unmap_frontend_data_rings(queue); 708 netif_napi_del(&queue->napi); 709 err: 710 module_put(THIS_MODULE); 711 return err; 712 } 713 714 void xenvif_carrier_off(struct xenvif *vif) 715 { 716 struct net_device *dev = vif->dev; 717 718 rtnl_lock(); 719 if (test_and_clear_bit(VIF_STATUS_CONNECTED, &vif->status)) { 720 netif_carrier_off(dev); /* discard queued packets */ 721 if (netif_running(dev)) 722 xenvif_down(vif); 723 } 724 rtnl_unlock(); 725 } 726 727 void xenvif_disconnect_data(struct xenvif *vif) 728 { 729 struct xenvif_queue *queue = NULL; 730 unsigned int num_queues = vif->num_queues; 731 unsigned int queue_index; 732 733 xenvif_carrier_off(vif); 734 735 for (queue_index = 0; queue_index < num_queues; ++queue_index) { 736 queue = &vif->queues[queue_index]; 737 738 netif_napi_del(&queue->napi); 739 740 if (queue->task) { 741 kthread_stop(queue->task); 742 put_task_struct(queue->task); 743 queue->task = NULL; 744 } 745 746 if (queue->dealloc_task) { 747 kthread_stop(queue->dealloc_task); 748 queue->dealloc_task = NULL; 749 } 750 751 if (queue->tx_irq) { 752 if (queue->tx_irq == queue->rx_irq) 753 unbind_from_irqhandler(queue->tx_irq, queue); 754 else { 755 unbind_from_irqhandler(queue->tx_irq, queue); 756 unbind_from_irqhandler(queue->rx_irq, queue); 757 } 758 queue->tx_irq = 0; 759 } 760 761 xenvif_unmap_frontend_data_rings(queue); 762 } 763 764 xenvif_mcast_addr_list_free(vif); 765 } 766 767 void xenvif_disconnect_ctrl(struct xenvif *vif) 768 { 769 if (vif->ctrl_irq) { 770 xenvif_deinit_hash(vif); 771 unbind_from_irqhandler(vif->ctrl_irq, vif); 772 vif->ctrl_irq = 0; 773 } 774 775 if (vif->ctrl.sring) { 776 xenbus_unmap_ring_vfree(xenvif_to_xenbus_device(vif), 777 vif->ctrl.sring); 778 vif->ctrl.sring = NULL; 779 } 780 } 781 782 /* Reverse the relevant parts of xenvif_init_queue(). 783 * Used for queue teardown from xenvif_free(), and on the 784 * error handling paths in xenbus.c:connect(). 785 */ 786 void xenvif_deinit_queue(struct xenvif_queue *queue) 787 { 788 gnttab_free_pages(MAX_PENDING_REQS, queue->mmap_pages); 789 } 790 791 void xenvif_free(struct xenvif *vif) 792 { 793 struct xenvif_queue *queues = vif->queues; 794 unsigned int num_queues = vif->num_queues; 795 unsigned int queue_index; 796 797 unregister_netdev(vif->dev); 798 free_netdev(vif->dev); 799 800 for (queue_index = 0; queue_index < num_queues; ++queue_index) 801 xenvif_deinit_queue(&queues[queue_index]); 802 vfree(queues); 803 804 module_put(THIS_MODULE); 805 } 806