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