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 /* If the queue is rate-limited, it shall be 110 * rescheduled in the timer callback. 111 */ 112 if (likely(!queue->rate_limited)) 113 xenvif_napi_schedule_or_enable_events(queue); 114 } 115 116 return work_done; 117 } 118 119 static irqreturn_t xenvif_rx_interrupt(int irq, void *dev_id) 120 { 121 struct xenvif_queue *queue = dev_id; 122 123 xenvif_kick_thread(queue); 124 125 return IRQ_HANDLED; 126 } 127 128 irqreturn_t xenvif_interrupt(int irq, void *dev_id) 129 { 130 xenvif_tx_interrupt(irq, dev_id); 131 xenvif_rx_interrupt(irq, dev_id); 132 133 return IRQ_HANDLED; 134 } 135 136 int xenvif_queue_stopped(struct xenvif_queue *queue) 137 { 138 struct net_device *dev = queue->vif->dev; 139 unsigned int id = queue->id; 140 return netif_tx_queue_stopped(netdev_get_tx_queue(dev, id)); 141 } 142 143 void xenvif_wake_queue(struct xenvif_queue *queue) 144 { 145 struct net_device *dev = queue->vif->dev; 146 unsigned int id = queue->id; 147 netif_tx_wake_queue(netdev_get_tx_queue(dev, id)); 148 } 149 150 static u16 xenvif_select_queue(struct net_device *dev, struct sk_buff *skb, 151 void *accel_priv, 152 select_queue_fallback_t fallback) 153 { 154 struct xenvif *vif = netdev_priv(dev); 155 unsigned int size = vif->hash.size; 156 157 if (vif->hash.alg == XEN_NETIF_CTRL_HASH_ALGORITHM_NONE) 158 return fallback(dev, skb) % dev->real_num_tx_queues; 159 160 xenvif_set_skb_hash(vif, skb); 161 162 if (size == 0) 163 return skb_get_hash_raw(skb) % dev->real_num_tx_queues; 164 165 return vif->hash.mapping[skb_get_hash_raw(skb) % size]; 166 } 167 168 static int xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev) 169 { 170 struct xenvif *vif = netdev_priv(dev); 171 struct xenvif_queue *queue = NULL; 172 unsigned int num_queues; 173 u16 index; 174 struct xenvif_rx_cb *cb; 175 176 BUG_ON(skb->dev != dev); 177 178 /* Drop the packet if queues are not set up. 179 * This handler should be called inside an RCU read section 180 * so we don't need to enter it here explicitly. 181 */ 182 num_queues = READ_ONCE(vif->num_queues); 183 if (num_queues < 1) 184 goto drop; 185 186 /* Obtain the queue to be used to transmit this packet */ 187 index = skb_get_queue_mapping(skb); 188 if (index >= num_queues) { 189 pr_warn_ratelimited("Invalid queue %hu for packet on interface %s\n.", 190 index, vif->dev->name); 191 index %= num_queues; 192 } 193 queue = &vif->queues[index]; 194 195 /* Drop the packet if queue is not ready */ 196 if (queue->task == NULL || 197 queue->dealloc_task == NULL || 198 !xenvif_schedulable(vif)) 199 goto drop; 200 201 if (vif->multicast_control && skb->pkt_type == PACKET_MULTICAST) { 202 struct ethhdr *eth = (struct ethhdr *)skb->data; 203 204 if (!xenvif_mcast_match(vif, eth->h_dest)) 205 goto drop; 206 } 207 208 cb = XENVIF_RX_CB(skb); 209 cb->expires = jiffies + vif->drain_timeout; 210 211 /* If there is no hash algorithm configured then make sure there 212 * is no hash information in the socket buffer otherwise it 213 * would be incorrectly forwarded to the frontend. 214 */ 215 if (vif->hash.alg == XEN_NETIF_CTRL_HASH_ALGORITHM_NONE) 216 skb_clear_hash(skb); 217 218 xenvif_rx_queue_tail(queue, skb); 219 xenvif_kick_thread(queue); 220 221 return NETDEV_TX_OK; 222 223 drop: 224 vif->dev->stats.tx_dropped++; 225 dev_kfree_skb(skb); 226 return NETDEV_TX_OK; 227 } 228 229 static struct net_device_stats *xenvif_get_stats(struct net_device *dev) 230 { 231 struct xenvif *vif = netdev_priv(dev); 232 struct xenvif_queue *queue = NULL; 233 unsigned int num_queues; 234 u64 rx_bytes = 0; 235 u64 rx_packets = 0; 236 u64 tx_bytes = 0; 237 u64 tx_packets = 0; 238 unsigned int index; 239 240 rcu_read_lock(); 241 num_queues = READ_ONCE(vif->num_queues); 242 243 /* Aggregate tx and rx stats from each queue */ 244 for (index = 0; index < num_queues; ++index) { 245 queue = &vif->queues[index]; 246 rx_bytes += queue->stats.rx_bytes; 247 rx_packets += queue->stats.rx_packets; 248 tx_bytes += queue->stats.tx_bytes; 249 tx_packets += queue->stats.tx_packets; 250 } 251 252 rcu_read_unlock(); 253 254 vif->dev->stats.rx_bytes = rx_bytes; 255 vif->dev->stats.rx_packets = rx_packets; 256 vif->dev->stats.tx_bytes = tx_bytes; 257 vif->dev->stats.tx_packets = tx_packets; 258 259 return &vif->dev->stats; 260 } 261 262 static void xenvif_up(struct xenvif *vif) 263 { 264 struct xenvif_queue *queue = NULL; 265 unsigned int num_queues = vif->num_queues; 266 unsigned int queue_index; 267 268 for (queue_index = 0; queue_index < num_queues; ++queue_index) { 269 queue = &vif->queues[queue_index]; 270 napi_enable(&queue->napi); 271 enable_irq(queue->tx_irq); 272 if (queue->tx_irq != queue->rx_irq) 273 enable_irq(queue->rx_irq); 274 xenvif_napi_schedule_or_enable_events(queue); 275 } 276 } 277 278 static void xenvif_down(struct xenvif *vif) 279 { 280 struct xenvif_queue *queue = NULL; 281 unsigned int num_queues = vif->num_queues; 282 unsigned int queue_index; 283 284 for (queue_index = 0; queue_index < num_queues; ++queue_index) { 285 queue = &vif->queues[queue_index]; 286 disable_irq(queue->tx_irq); 287 if (queue->tx_irq != queue->rx_irq) 288 disable_irq(queue->rx_irq); 289 napi_disable(&queue->napi); 290 del_timer_sync(&queue->credit_timeout); 291 } 292 } 293 294 static int xenvif_open(struct net_device *dev) 295 { 296 struct xenvif *vif = netdev_priv(dev); 297 if (test_bit(VIF_STATUS_CONNECTED, &vif->status)) 298 xenvif_up(vif); 299 netif_tx_start_all_queues(dev); 300 return 0; 301 } 302 303 static int xenvif_close(struct net_device *dev) 304 { 305 struct xenvif *vif = netdev_priv(dev); 306 if (test_bit(VIF_STATUS_CONNECTED, &vif->status)) 307 xenvif_down(vif); 308 netif_tx_stop_all_queues(dev); 309 return 0; 310 } 311 312 static int xenvif_change_mtu(struct net_device *dev, int mtu) 313 { 314 struct xenvif *vif = netdev_priv(dev); 315 int max = vif->can_sg ? ETH_MAX_MTU - VLAN_ETH_HLEN : ETH_DATA_LEN; 316 317 if (mtu > max) 318 return -EINVAL; 319 dev->mtu = mtu; 320 return 0; 321 } 322 323 static netdev_features_t xenvif_fix_features(struct net_device *dev, 324 netdev_features_t features) 325 { 326 struct xenvif *vif = netdev_priv(dev); 327 328 if (!vif->can_sg) 329 features &= ~NETIF_F_SG; 330 if (~(vif->gso_mask) & GSO_BIT(TCPV4)) 331 features &= ~NETIF_F_TSO; 332 if (~(vif->gso_mask) & GSO_BIT(TCPV6)) 333 features &= ~NETIF_F_TSO6; 334 if (!vif->ip_csum) 335 features &= ~NETIF_F_IP_CSUM; 336 if (!vif->ipv6_csum) 337 features &= ~NETIF_F_IPV6_CSUM; 338 339 return features; 340 } 341 342 static const struct xenvif_stat { 343 char name[ETH_GSTRING_LEN]; 344 u16 offset; 345 } xenvif_stats[] = { 346 { 347 "rx_gso_checksum_fixup", 348 offsetof(struct xenvif_stats, rx_gso_checksum_fixup) 349 }, 350 /* If (sent != success + fail), there are probably packets never 351 * freed up properly! 352 */ 353 { 354 "tx_zerocopy_sent", 355 offsetof(struct xenvif_stats, tx_zerocopy_sent), 356 }, 357 { 358 "tx_zerocopy_success", 359 offsetof(struct xenvif_stats, tx_zerocopy_success), 360 }, 361 { 362 "tx_zerocopy_fail", 363 offsetof(struct xenvif_stats, tx_zerocopy_fail) 364 }, 365 /* Number of packets exceeding MAX_SKB_FRAG slots. You should use 366 * a guest with the same MAX_SKB_FRAG 367 */ 368 { 369 "tx_frag_overflow", 370 offsetof(struct xenvif_stats, tx_frag_overflow) 371 }, 372 }; 373 374 static int xenvif_get_sset_count(struct net_device *dev, int string_set) 375 { 376 switch (string_set) { 377 case ETH_SS_STATS: 378 return ARRAY_SIZE(xenvif_stats); 379 default: 380 return -EINVAL; 381 } 382 } 383 384 static void xenvif_get_ethtool_stats(struct net_device *dev, 385 struct ethtool_stats *stats, u64 * data) 386 { 387 struct xenvif *vif = netdev_priv(dev); 388 unsigned int num_queues; 389 int i; 390 unsigned int queue_index; 391 392 rcu_read_lock(); 393 num_queues = READ_ONCE(vif->num_queues); 394 395 for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++) { 396 unsigned long accum = 0; 397 for (queue_index = 0; queue_index < num_queues; ++queue_index) { 398 void *vif_stats = &vif->queues[queue_index].stats; 399 accum += *(unsigned long *)(vif_stats + xenvif_stats[i].offset); 400 } 401 data[i] = accum; 402 } 403 404 rcu_read_unlock(); 405 } 406 407 static void xenvif_get_strings(struct net_device *dev, u32 stringset, u8 * data) 408 { 409 int i; 410 411 switch (stringset) { 412 case ETH_SS_STATS: 413 for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++) 414 memcpy(data + i * ETH_GSTRING_LEN, 415 xenvif_stats[i].name, ETH_GSTRING_LEN); 416 break; 417 } 418 } 419 420 static const struct ethtool_ops xenvif_ethtool_ops = { 421 .get_link = ethtool_op_get_link, 422 423 .get_sset_count = xenvif_get_sset_count, 424 .get_ethtool_stats = xenvif_get_ethtool_stats, 425 .get_strings = xenvif_get_strings, 426 }; 427 428 static const struct net_device_ops xenvif_netdev_ops = { 429 .ndo_select_queue = xenvif_select_queue, 430 .ndo_start_xmit = xenvif_start_xmit, 431 .ndo_get_stats = xenvif_get_stats, 432 .ndo_open = xenvif_open, 433 .ndo_stop = xenvif_close, 434 .ndo_change_mtu = xenvif_change_mtu, 435 .ndo_fix_features = xenvif_fix_features, 436 .ndo_set_mac_address = eth_mac_addr, 437 .ndo_validate_addr = eth_validate_addr, 438 }; 439 440 struct xenvif *xenvif_alloc(struct device *parent, domid_t domid, 441 unsigned int handle) 442 { 443 int err; 444 struct net_device *dev; 445 struct xenvif *vif; 446 char name[IFNAMSIZ] = {}; 447 448 snprintf(name, IFNAMSIZ - 1, "vif%u.%u", domid, handle); 449 /* Allocate a netdev with the max. supported number of queues. 450 * When the guest selects the desired number, it will be updated 451 * via netif_set_real_num_*_queues(). 452 */ 453 dev = alloc_netdev_mq(sizeof(struct xenvif), name, NET_NAME_UNKNOWN, 454 ether_setup, xenvif_max_queues); 455 if (dev == NULL) { 456 pr_warn("Could not allocate netdev for %s\n", name); 457 return ERR_PTR(-ENOMEM); 458 } 459 460 SET_NETDEV_DEV(dev, parent); 461 462 vif = netdev_priv(dev); 463 464 vif->domid = domid; 465 vif->handle = handle; 466 vif->can_sg = 1; 467 vif->ip_csum = 1; 468 vif->dev = dev; 469 vif->disabled = false; 470 vif->drain_timeout = msecs_to_jiffies(rx_drain_timeout_msecs); 471 vif->stall_timeout = msecs_to_jiffies(rx_stall_timeout_msecs); 472 473 /* Start out with no queues. */ 474 vif->queues = NULL; 475 vif->num_queues = 0; 476 477 spin_lock_init(&vif->lock); 478 INIT_LIST_HEAD(&vif->fe_mcast_addr); 479 480 dev->netdev_ops = &xenvif_netdev_ops; 481 dev->hw_features = NETIF_F_SG | 482 NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM | 483 NETIF_F_TSO | NETIF_F_TSO6 | NETIF_F_FRAGLIST; 484 dev->features = dev->hw_features | NETIF_F_RXCSUM; 485 dev->ethtool_ops = &xenvif_ethtool_ops; 486 487 dev->tx_queue_len = XENVIF_QUEUE_LENGTH; 488 489 dev->min_mtu = 0; 490 dev->max_mtu = ETH_MAX_MTU - VLAN_ETH_HLEN; 491 492 /* 493 * Initialise a dummy MAC address. We choose the numerically 494 * largest non-broadcast address to prevent the address getting 495 * stolen by an Ethernet bridge for STP purposes. 496 * (FE:FF:FF:FF:FF:FF) 497 */ 498 eth_broadcast_addr(dev->dev_addr); 499 dev->dev_addr[0] &= ~0x01; 500 501 netif_carrier_off(dev); 502 503 err = register_netdev(dev); 504 if (err) { 505 netdev_warn(dev, "Could not register device: err=%d\n", err); 506 free_netdev(dev); 507 return ERR_PTR(err); 508 } 509 510 netdev_dbg(dev, "Successfully created xenvif\n"); 511 512 __module_get(THIS_MODULE); 513 514 return vif; 515 } 516 517 int xenvif_init_queue(struct xenvif_queue *queue) 518 { 519 int err, i; 520 521 queue->credit_bytes = queue->remaining_credit = ~0UL; 522 queue->credit_usec = 0UL; 523 init_timer(&queue->credit_timeout); 524 queue->credit_timeout.function = xenvif_tx_credit_callback; 525 queue->credit_window_start = get_jiffies_64(); 526 527 queue->rx_queue_max = XENVIF_RX_QUEUE_BYTES; 528 529 skb_queue_head_init(&queue->rx_queue); 530 skb_queue_head_init(&queue->tx_queue); 531 532 queue->pending_cons = 0; 533 queue->pending_prod = MAX_PENDING_REQS; 534 for (i = 0; i < MAX_PENDING_REQS; ++i) 535 queue->pending_ring[i] = i; 536 537 spin_lock_init(&queue->callback_lock); 538 spin_lock_init(&queue->response_lock); 539 540 /* If ballooning is disabled, this will consume real memory, so you 541 * better enable it. The long term solution would be to use just a 542 * bunch of valid page descriptors, without dependency on ballooning 543 */ 544 err = gnttab_alloc_pages(MAX_PENDING_REQS, 545 queue->mmap_pages); 546 if (err) { 547 netdev_err(queue->vif->dev, "Could not reserve mmap_pages\n"); 548 return -ENOMEM; 549 } 550 551 for (i = 0; i < MAX_PENDING_REQS; i++) { 552 queue->pending_tx_info[i].callback_struct = (struct ubuf_info) 553 { .callback = xenvif_zerocopy_callback, 554 { { .ctx = NULL, 555 .desc = i } } }; 556 queue->grant_tx_handle[i] = NETBACK_INVALID_HANDLE; 557 } 558 559 return 0; 560 } 561 562 void xenvif_carrier_on(struct xenvif *vif) 563 { 564 rtnl_lock(); 565 if (!vif->can_sg && vif->dev->mtu > ETH_DATA_LEN) 566 dev_set_mtu(vif->dev, ETH_DATA_LEN); 567 netdev_update_features(vif->dev); 568 set_bit(VIF_STATUS_CONNECTED, &vif->status); 569 if (netif_running(vif->dev)) 570 xenvif_up(vif); 571 rtnl_unlock(); 572 } 573 574 int xenvif_connect_ctrl(struct xenvif *vif, grant_ref_t ring_ref, 575 unsigned int evtchn) 576 { 577 struct net_device *dev = vif->dev; 578 void *addr; 579 struct xen_netif_ctrl_sring *shared; 580 int err; 581 582 err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(vif), 583 &ring_ref, 1, &addr); 584 if (err) 585 goto err; 586 587 shared = (struct xen_netif_ctrl_sring *)addr; 588 BACK_RING_INIT(&vif->ctrl, shared, XEN_PAGE_SIZE); 589 590 err = bind_interdomain_evtchn_to_irq(vif->domid, evtchn); 591 if (err < 0) 592 goto err_unmap; 593 594 vif->ctrl_irq = err; 595 596 xenvif_init_hash(vif); 597 598 err = request_threaded_irq(vif->ctrl_irq, NULL, xenvif_ctrl_irq_fn, 599 IRQF_ONESHOT, "xen-netback-ctrl", vif); 600 if (err) { 601 pr_warn("Could not setup irq handler for %s\n", dev->name); 602 goto err_deinit; 603 } 604 605 return 0; 606 607 err_deinit: 608 xenvif_deinit_hash(vif); 609 unbind_from_irqhandler(vif->ctrl_irq, vif); 610 vif->ctrl_irq = 0; 611 612 err_unmap: 613 xenbus_unmap_ring_vfree(xenvif_to_xenbus_device(vif), 614 vif->ctrl.sring); 615 vif->ctrl.sring = NULL; 616 617 err: 618 return err; 619 } 620 621 int xenvif_connect_data(struct xenvif_queue *queue, 622 unsigned long tx_ring_ref, 623 unsigned long rx_ring_ref, 624 unsigned int tx_evtchn, 625 unsigned int rx_evtchn) 626 { 627 struct task_struct *task; 628 int err = -ENOMEM; 629 630 BUG_ON(queue->tx_irq); 631 BUG_ON(queue->task); 632 BUG_ON(queue->dealloc_task); 633 634 err = xenvif_map_frontend_data_rings(queue, tx_ring_ref, 635 rx_ring_ref); 636 if (err < 0) 637 goto err; 638 639 init_waitqueue_head(&queue->wq); 640 init_waitqueue_head(&queue->dealloc_wq); 641 atomic_set(&queue->inflight_packets, 0); 642 643 netif_napi_add(queue->vif->dev, &queue->napi, xenvif_poll, 644 XENVIF_NAPI_WEIGHT); 645 646 if (tx_evtchn == rx_evtchn) { 647 /* feature-split-event-channels == 0 */ 648 err = bind_interdomain_evtchn_to_irqhandler( 649 queue->vif->domid, tx_evtchn, xenvif_interrupt, 0, 650 queue->name, queue); 651 if (err < 0) 652 goto err_unmap; 653 queue->tx_irq = queue->rx_irq = err; 654 disable_irq(queue->tx_irq); 655 } else { 656 /* feature-split-event-channels == 1 */ 657 snprintf(queue->tx_irq_name, sizeof(queue->tx_irq_name), 658 "%s-tx", queue->name); 659 err = bind_interdomain_evtchn_to_irqhandler( 660 queue->vif->domid, tx_evtchn, xenvif_tx_interrupt, 0, 661 queue->tx_irq_name, queue); 662 if (err < 0) 663 goto err_unmap; 664 queue->tx_irq = err; 665 disable_irq(queue->tx_irq); 666 667 snprintf(queue->rx_irq_name, sizeof(queue->rx_irq_name), 668 "%s-rx", queue->name); 669 err = bind_interdomain_evtchn_to_irqhandler( 670 queue->vif->domid, rx_evtchn, xenvif_rx_interrupt, 0, 671 queue->rx_irq_name, queue); 672 if (err < 0) 673 goto err_tx_unbind; 674 queue->rx_irq = err; 675 disable_irq(queue->rx_irq); 676 } 677 678 queue->stalled = true; 679 680 task = kthread_create(xenvif_kthread_guest_rx, 681 (void *)queue, "%s-guest-rx", queue->name); 682 if (IS_ERR(task)) { 683 pr_warn("Could not allocate kthread for %s\n", queue->name); 684 err = PTR_ERR(task); 685 goto err_rx_unbind; 686 } 687 queue->task = task; 688 get_task_struct(task); 689 690 task = kthread_create(xenvif_dealloc_kthread, 691 (void *)queue, "%s-dealloc", queue->name); 692 if (IS_ERR(task)) { 693 pr_warn("Could not allocate kthread for %s\n", queue->name); 694 err = PTR_ERR(task); 695 goto err_rx_unbind; 696 } 697 queue->dealloc_task = task; 698 699 wake_up_process(queue->task); 700 wake_up_process(queue->dealloc_task); 701 702 return 0; 703 704 err_rx_unbind: 705 unbind_from_irqhandler(queue->rx_irq, queue); 706 queue->rx_irq = 0; 707 err_tx_unbind: 708 unbind_from_irqhandler(queue->tx_irq, queue); 709 queue->tx_irq = 0; 710 err_unmap: 711 xenvif_unmap_frontend_data_rings(queue); 712 netif_napi_del(&queue->napi); 713 err: 714 module_put(THIS_MODULE); 715 return err; 716 } 717 718 void xenvif_carrier_off(struct xenvif *vif) 719 { 720 struct net_device *dev = vif->dev; 721 722 rtnl_lock(); 723 if (test_and_clear_bit(VIF_STATUS_CONNECTED, &vif->status)) { 724 netif_carrier_off(dev); /* discard queued packets */ 725 if (netif_running(dev)) 726 xenvif_down(vif); 727 } 728 rtnl_unlock(); 729 } 730 731 void xenvif_disconnect_data(struct xenvif *vif) 732 { 733 struct xenvif_queue *queue = NULL; 734 unsigned int num_queues = vif->num_queues; 735 unsigned int queue_index; 736 737 xenvif_carrier_off(vif); 738 739 for (queue_index = 0; queue_index < num_queues; ++queue_index) { 740 queue = &vif->queues[queue_index]; 741 742 netif_napi_del(&queue->napi); 743 744 if (queue->task) { 745 kthread_stop(queue->task); 746 put_task_struct(queue->task); 747 queue->task = NULL; 748 } 749 750 if (queue->dealloc_task) { 751 kthread_stop(queue->dealloc_task); 752 queue->dealloc_task = NULL; 753 } 754 755 if (queue->tx_irq) { 756 if (queue->tx_irq == queue->rx_irq) 757 unbind_from_irqhandler(queue->tx_irq, queue); 758 else { 759 unbind_from_irqhandler(queue->tx_irq, queue); 760 unbind_from_irqhandler(queue->rx_irq, queue); 761 } 762 queue->tx_irq = 0; 763 } 764 765 xenvif_unmap_frontend_data_rings(queue); 766 } 767 768 xenvif_mcast_addr_list_free(vif); 769 } 770 771 void xenvif_disconnect_ctrl(struct xenvif *vif) 772 { 773 if (vif->ctrl_irq) { 774 xenvif_deinit_hash(vif); 775 unbind_from_irqhandler(vif->ctrl_irq, vif); 776 vif->ctrl_irq = 0; 777 } 778 779 if (vif->ctrl.sring) { 780 xenbus_unmap_ring_vfree(xenvif_to_xenbus_device(vif), 781 vif->ctrl.sring); 782 vif->ctrl.sring = NULL; 783 } 784 } 785 786 /* Reverse the relevant parts of xenvif_init_queue(). 787 * Used for queue teardown from xenvif_free(), and on the 788 * error handling paths in xenbus.c:connect(). 789 */ 790 void xenvif_deinit_queue(struct xenvif_queue *queue) 791 { 792 gnttab_free_pages(MAX_PENDING_REQS, queue->mmap_pages); 793 } 794 795 void xenvif_free(struct xenvif *vif) 796 { 797 struct xenvif_queue *queues = vif->queues; 798 unsigned int num_queues = vif->num_queues; 799 unsigned int queue_index; 800 801 unregister_netdev(vif->dev); 802 free_netdev(vif->dev); 803 804 for (queue_index = 0; queue_index < num_queues; ++queue_index) 805 xenvif_deinit_queue(&queues[queue_index]); 806 vfree(queues); 807 808 module_put(THIS_MODULE); 809 } 810