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 struct net_device *sb_dev) 152 { 153 struct xenvif *vif = netdev_priv(dev); 154 unsigned int size = vif->hash.size; 155 unsigned int num_queues; 156 157 /* If queues are not set up internally - always return 0 158 * as the packet going to be dropped anyway */ 159 num_queues = READ_ONCE(vif->num_queues); 160 if (num_queues < 1) 161 return 0; 162 163 if (vif->hash.alg == XEN_NETIF_CTRL_HASH_ALGORITHM_NONE) 164 return netdev_pick_tx(dev, skb, NULL) % 165 dev->real_num_tx_queues; 166 167 xenvif_set_skb_hash(vif, skb); 168 169 if (size == 0) 170 return skb_get_hash_raw(skb) % dev->real_num_tx_queues; 171 172 return vif->hash.mapping[vif->hash.mapping_sel] 173 [skb_get_hash_raw(skb) % size]; 174 } 175 176 static netdev_tx_t 177 xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev) 178 { 179 struct xenvif *vif = netdev_priv(dev); 180 struct xenvif_queue *queue = NULL; 181 unsigned int num_queues; 182 u16 index; 183 struct xenvif_rx_cb *cb; 184 185 BUG_ON(skb->dev != dev); 186 187 /* Drop the packet if queues are not set up. 188 * This handler should be called inside an RCU read section 189 * so we don't need to enter it here explicitly. 190 */ 191 num_queues = READ_ONCE(vif->num_queues); 192 if (num_queues < 1) 193 goto drop; 194 195 /* Obtain the queue to be used to transmit this packet */ 196 index = skb_get_queue_mapping(skb); 197 if (index >= num_queues) { 198 pr_warn_ratelimited("Invalid queue %hu for packet on interface %s\n", 199 index, vif->dev->name); 200 index %= num_queues; 201 } 202 queue = &vif->queues[index]; 203 204 /* Drop the packet if queue is not ready */ 205 if (queue->task == NULL || 206 queue->dealloc_task == NULL || 207 !xenvif_schedulable(vif)) 208 goto drop; 209 210 if (vif->multicast_control && skb->pkt_type == PACKET_MULTICAST) { 211 struct ethhdr *eth = (struct ethhdr *)skb->data; 212 213 if (!xenvif_mcast_match(vif, eth->h_dest)) 214 goto drop; 215 } 216 217 cb = XENVIF_RX_CB(skb); 218 cb->expires = jiffies + vif->drain_timeout; 219 220 /* If there is no hash algorithm configured then make sure there 221 * is no hash information in the socket buffer otherwise it 222 * would be incorrectly forwarded to the frontend. 223 */ 224 if (vif->hash.alg == XEN_NETIF_CTRL_HASH_ALGORITHM_NONE) 225 skb_clear_hash(skb); 226 227 xenvif_rx_queue_tail(queue, skb); 228 xenvif_kick_thread(queue); 229 230 return NETDEV_TX_OK; 231 232 drop: 233 vif->dev->stats.tx_dropped++; 234 dev_kfree_skb(skb); 235 return NETDEV_TX_OK; 236 } 237 238 static struct net_device_stats *xenvif_get_stats(struct net_device *dev) 239 { 240 struct xenvif *vif = netdev_priv(dev); 241 struct xenvif_queue *queue = NULL; 242 unsigned int num_queues; 243 u64 rx_bytes = 0; 244 u64 rx_packets = 0; 245 u64 tx_bytes = 0; 246 u64 tx_packets = 0; 247 unsigned int index; 248 249 rcu_read_lock(); 250 num_queues = READ_ONCE(vif->num_queues); 251 252 /* Aggregate tx and rx stats from each queue */ 253 for (index = 0; index < num_queues; ++index) { 254 queue = &vif->queues[index]; 255 rx_bytes += queue->stats.rx_bytes; 256 rx_packets += queue->stats.rx_packets; 257 tx_bytes += queue->stats.tx_bytes; 258 tx_packets += queue->stats.tx_packets; 259 } 260 261 rcu_read_unlock(); 262 263 vif->dev->stats.rx_bytes = rx_bytes; 264 vif->dev->stats.rx_packets = rx_packets; 265 vif->dev->stats.tx_bytes = tx_bytes; 266 vif->dev->stats.tx_packets = tx_packets; 267 268 return &vif->dev->stats; 269 } 270 271 static void xenvif_up(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 napi_enable(&queue->napi); 280 enable_irq(queue->tx_irq); 281 if (queue->tx_irq != queue->rx_irq) 282 enable_irq(queue->rx_irq); 283 xenvif_napi_schedule_or_enable_events(queue); 284 } 285 } 286 287 static void xenvif_down(struct xenvif *vif) 288 { 289 struct xenvif_queue *queue = NULL; 290 unsigned int num_queues = vif->num_queues; 291 unsigned int queue_index; 292 293 for (queue_index = 0; queue_index < num_queues; ++queue_index) { 294 queue = &vif->queues[queue_index]; 295 disable_irq(queue->tx_irq); 296 if (queue->tx_irq != queue->rx_irq) 297 disable_irq(queue->rx_irq); 298 napi_disable(&queue->napi); 299 del_timer_sync(&queue->credit_timeout); 300 } 301 } 302 303 static int xenvif_open(struct net_device *dev) 304 { 305 struct xenvif *vif = netdev_priv(dev); 306 if (test_bit(VIF_STATUS_CONNECTED, &vif->status)) 307 xenvif_up(vif); 308 netif_tx_start_all_queues(dev); 309 return 0; 310 } 311 312 static int xenvif_close(struct net_device *dev) 313 { 314 struct xenvif *vif = netdev_priv(dev); 315 if (test_bit(VIF_STATUS_CONNECTED, &vif->status)) 316 xenvif_down(vif); 317 netif_tx_stop_all_queues(dev); 318 return 0; 319 } 320 321 static int xenvif_change_mtu(struct net_device *dev, int mtu) 322 { 323 struct xenvif *vif = netdev_priv(dev); 324 int max = vif->can_sg ? ETH_MAX_MTU - VLAN_ETH_HLEN : ETH_DATA_LEN; 325 326 if (mtu > max) 327 return -EINVAL; 328 dev->mtu = mtu; 329 return 0; 330 } 331 332 static netdev_features_t xenvif_fix_features(struct net_device *dev, 333 netdev_features_t features) 334 { 335 struct xenvif *vif = netdev_priv(dev); 336 337 if (!vif->can_sg) 338 features &= ~NETIF_F_SG; 339 if (~(vif->gso_mask) & GSO_BIT(TCPV4)) 340 features &= ~NETIF_F_TSO; 341 if (~(vif->gso_mask) & GSO_BIT(TCPV6)) 342 features &= ~NETIF_F_TSO6; 343 if (!vif->ip_csum) 344 features &= ~NETIF_F_IP_CSUM; 345 if (!vif->ipv6_csum) 346 features &= ~NETIF_F_IPV6_CSUM; 347 348 return features; 349 } 350 351 static const struct xenvif_stat { 352 char name[ETH_GSTRING_LEN]; 353 u16 offset; 354 } xenvif_stats[] = { 355 { 356 "rx_gso_checksum_fixup", 357 offsetof(struct xenvif_stats, rx_gso_checksum_fixup) 358 }, 359 /* If (sent != success + fail), there are probably packets never 360 * freed up properly! 361 */ 362 { 363 "tx_zerocopy_sent", 364 offsetof(struct xenvif_stats, tx_zerocopy_sent), 365 }, 366 { 367 "tx_zerocopy_success", 368 offsetof(struct xenvif_stats, tx_zerocopy_success), 369 }, 370 { 371 "tx_zerocopy_fail", 372 offsetof(struct xenvif_stats, tx_zerocopy_fail) 373 }, 374 /* Number of packets exceeding MAX_SKB_FRAG slots. You should use 375 * a guest with the same MAX_SKB_FRAG 376 */ 377 { 378 "tx_frag_overflow", 379 offsetof(struct xenvif_stats, tx_frag_overflow) 380 }, 381 }; 382 383 static int xenvif_get_sset_count(struct net_device *dev, int string_set) 384 { 385 switch (string_set) { 386 case ETH_SS_STATS: 387 return ARRAY_SIZE(xenvif_stats); 388 default: 389 return -EINVAL; 390 } 391 } 392 393 static void xenvif_get_ethtool_stats(struct net_device *dev, 394 struct ethtool_stats *stats, u64 * data) 395 { 396 struct xenvif *vif = netdev_priv(dev); 397 unsigned int num_queues; 398 int i; 399 unsigned int queue_index; 400 401 rcu_read_lock(); 402 num_queues = READ_ONCE(vif->num_queues); 403 404 for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++) { 405 unsigned long accum = 0; 406 for (queue_index = 0; queue_index < num_queues; ++queue_index) { 407 void *vif_stats = &vif->queues[queue_index].stats; 408 accum += *(unsigned long *)(vif_stats + xenvif_stats[i].offset); 409 } 410 data[i] = accum; 411 } 412 413 rcu_read_unlock(); 414 } 415 416 static void xenvif_get_strings(struct net_device *dev, u32 stringset, u8 * data) 417 { 418 int i; 419 420 switch (stringset) { 421 case ETH_SS_STATS: 422 for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++) 423 memcpy(data + i * ETH_GSTRING_LEN, 424 xenvif_stats[i].name, ETH_GSTRING_LEN); 425 break; 426 } 427 } 428 429 static const struct ethtool_ops xenvif_ethtool_ops = { 430 .get_link = ethtool_op_get_link, 431 432 .get_sset_count = xenvif_get_sset_count, 433 .get_ethtool_stats = xenvif_get_ethtool_stats, 434 .get_strings = xenvif_get_strings, 435 }; 436 437 static const struct net_device_ops xenvif_netdev_ops = { 438 .ndo_select_queue = xenvif_select_queue, 439 .ndo_start_xmit = xenvif_start_xmit, 440 .ndo_get_stats = xenvif_get_stats, 441 .ndo_open = xenvif_open, 442 .ndo_stop = xenvif_close, 443 .ndo_change_mtu = xenvif_change_mtu, 444 .ndo_fix_features = xenvif_fix_features, 445 .ndo_set_mac_address = eth_mac_addr, 446 .ndo_validate_addr = eth_validate_addr, 447 }; 448 449 struct xenvif *xenvif_alloc(struct device *parent, domid_t domid, 450 unsigned int handle) 451 { 452 int err; 453 struct net_device *dev; 454 struct xenvif *vif; 455 char name[IFNAMSIZ] = {}; 456 457 snprintf(name, IFNAMSIZ - 1, "vif%u.%u", domid, handle); 458 /* Allocate a netdev with the max. supported number of queues. 459 * When the guest selects the desired number, it will be updated 460 * via netif_set_real_num_*_queues(). 461 */ 462 dev = alloc_netdev_mq(sizeof(struct xenvif), name, NET_NAME_UNKNOWN, 463 ether_setup, xenvif_max_queues); 464 if (dev == NULL) { 465 pr_warn("Could not allocate netdev for %s\n", name); 466 return ERR_PTR(-ENOMEM); 467 } 468 469 SET_NETDEV_DEV(dev, parent); 470 471 vif = netdev_priv(dev); 472 473 vif->domid = domid; 474 vif->handle = handle; 475 vif->can_sg = 1; 476 vif->ip_csum = 1; 477 vif->dev = dev; 478 vif->disabled = false; 479 vif->drain_timeout = msecs_to_jiffies(rx_drain_timeout_msecs); 480 vif->stall_timeout = msecs_to_jiffies(rx_stall_timeout_msecs); 481 482 /* Start out with no queues. */ 483 vif->queues = NULL; 484 vif->num_queues = 0; 485 486 spin_lock_init(&vif->lock); 487 INIT_LIST_HEAD(&vif->fe_mcast_addr); 488 489 dev->netdev_ops = &xenvif_netdev_ops; 490 dev->hw_features = NETIF_F_SG | 491 NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM | 492 NETIF_F_TSO | NETIF_F_TSO6 | NETIF_F_FRAGLIST; 493 dev->features = dev->hw_features | NETIF_F_RXCSUM; 494 dev->ethtool_ops = &xenvif_ethtool_ops; 495 496 dev->tx_queue_len = XENVIF_QUEUE_LENGTH; 497 498 dev->min_mtu = ETH_MIN_MTU; 499 dev->max_mtu = ETH_MAX_MTU - VLAN_ETH_HLEN; 500 501 /* 502 * Initialise a dummy MAC address. We choose the numerically 503 * largest non-broadcast address to prevent the address getting 504 * stolen by an Ethernet bridge for STP purposes. 505 * (FE:FF:FF:FF:FF:FF) 506 */ 507 eth_broadcast_addr(dev->dev_addr); 508 dev->dev_addr[0] &= ~0x01; 509 510 netif_carrier_off(dev); 511 512 err = register_netdev(dev); 513 if (err) { 514 netdev_warn(dev, "Could not register device: err=%d\n", err); 515 free_netdev(dev); 516 return ERR_PTR(err); 517 } 518 519 netdev_dbg(dev, "Successfully created xenvif\n"); 520 521 __module_get(THIS_MODULE); 522 523 return vif; 524 } 525 526 int xenvif_init_queue(struct xenvif_queue *queue) 527 { 528 int err, i; 529 530 queue->credit_bytes = queue->remaining_credit = ~0UL; 531 queue->credit_usec = 0UL; 532 timer_setup(&queue->credit_timeout, xenvif_tx_credit_callback, 0); 533 queue->credit_window_start = get_jiffies_64(); 534 535 queue->rx_queue_max = XENVIF_RX_QUEUE_BYTES; 536 537 skb_queue_head_init(&queue->rx_queue); 538 skb_queue_head_init(&queue->tx_queue); 539 540 queue->pending_cons = 0; 541 queue->pending_prod = MAX_PENDING_REQS; 542 for (i = 0; i < MAX_PENDING_REQS; ++i) 543 queue->pending_ring[i] = i; 544 545 spin_lock_init(&queue->callback_lock); 546 spin_lock_init(&queue->response_lock); 547 548 /* If ballooning is disabled, this will consume real memory, so you 549 * better enable it. The long term solution would be to use just a 550 * bunch of valid page descriptors, without dependency on ballooning 551 */ 552 err = gnttab_alloc_pages(MAX_PENDING_REQS, 553 queue->mmap_pages); 554 if (err) { 555 netdev_err(queue->vif->dev, "Could not reserve mmap_pages\n"); 556 return -ENOMEM; 557 } 558 559 for (i = 0; i < MAX_PENDING_REQS; i++) { 560 queue->pending_tx_info[i].callback_struct = (struct ubuf_info) 561 { .callback = xenvif_zerocopy_callback, 562 { { .ctx = NULL, 563 .desc = i } } }; 564 queue->grant_tx_handle[i] = NETBACK_INVALID_HANDLE; 565 } 566 567 return 0; 568 } 569 570 void xenvif_carrier_on(struct xenvif *vif) 571 { 572 rtnl_lock(); 573 if (!vif->can_sg && vif->dev->mtu > ETH_DATA_LEN) 574 dev_set_mtu(vif->dev, ETH_DATA_LEN); 575 netdev_update_features(vif->dev); 576 set_bit(VIF_STATUS_CONNECTED, &vif->status); 577 if (netif_running(vif->dev)) 578 xenvif_up(vif); 579 rtnl_unlock(); 580 } 581 582 int xenvif_connect_ctrl(struct xenvif *vif, grant_ref_t ring_ref, 583 unsigned int evtchn) 584 { 585 struct net_device *dev = vif->dev; 586 void *addr; 587 struct xen_netif_ctrl_sring *shared; 588 RING_IDX rsp_prod, req_prod; 589 int err; 590 591 err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(vif), 592 &ring_ref, 1, &addr); 593 if (err) 594 goto err; 595 596 shared = (struct xen_netif_ctrl_sring *)addr; 597 rsp_prod = READ_ONCE(shared->rsp_prod); 598 req_prod = READ_ONCE(shared->req_prod); 599 600 BACK_RING_ATTACH(&vif->ctrl, shared, rsp_prod, XEN_PAGE_SIZE); 601 602 err = -EIO; 603 if (req_prod - rsp_prod > RING_SIZE(&vif->ctrl)) 604 goto err_unmap; 605 606 err = bind_interdomain_evtchn_to_irq(vif->domid, evtchn); 607 if (err < 0) 608 goto err_unmap; 609 610 vif->ctrl_irq = err; 611 612 xenvif_init_hash(vif); 613 614 err = request_threaded_irq(vif->ctrl_irq, NULL, xenvif_ctrl_irq_fn, 615 IRQF_ONESHOT, "xen-netback-ctrl", vif); 616 if (err) { 617 pr_warn("Could not setup irq handler for %s\n", dev->name); 618 goto err_deinit; 619 } 620 621 return 0; 622 623 err_deinit: 624 xenvif_deinit_hash(vif); 625 unbind_from_irqhandler(vif->ctrl_irq, vif); 626 vif->ctrl_irq = 0; 627 628 err_unmap: 629 xenbus_unmap_ring_vfree(xenvif_to_xenbus_device(vif), 630 vif->ctrl.sring); 631 vif->ctrl.sring = NULL; 632 633 err: 634 return err; 635 } 636 637 static void xenvif_disconnect_queue(struct xenvif_queue *queue) 638 { 639 if (queue->task) { 640 kthread_stop(queue->task); 641 queue->task = NULL; 642 } 643 644 if (queue->dealloc_task) { 645 kthread_stop(queue->dealloc_task); 646 queue->dealloc_task = NULL; 647 } 648 649 if (queue->napi.poll) { 650 netif_napi_del(&queue->napi); 651 queue->napi.poll = NULL; 652 } 653 654 if (queue->tx_irq) { 655 unbind_from_irqhandler(queue->tx_irq, queue); 656 if (queue->tx_irq == queue->rx_irq) 657 queue->rx_irq = 0; 658 queue->tx_irq = 0; 659 } 660 661 if (queue->rx_irq) { 662 unbind_from_irqhandler(queue->rx_irq, queue); 663 queue->rx_irq = 0; 664 } 665 666 xenvif_unmap_frontend_data_rings(queue); 667 } 668 669 int xenvif_connect_data(struct xenvif_queue *queue, 670 unsigned long tx_ring_ref, 671 unsigned long rx_ring_ref, 672 unsigned int tx_evtchn, 673 unsigned int rx_evtchn) 674 { 675 struct task_struct *task; 676 int err; 677 678 BUG_ON(queue->tx_irq); 679 BUG_ON(queue->task); 680 BUG_ON(queue->dealloc_task); 681 682 err = xenvif_map_frontend_data_rings(queue, tx_ring_ref, 683 rx_ring_ref); 684 if (err < 0) 685 goto err; 686 687 init_waitqueue_head(&queue->wq); 688 init_waitqueue_head(&queue->dealloc_wq); 689 atomic_set(&queue->inflight_packets, 0); 690 691 netif_napi_add(queue->vif->dev, &queue->napi, xenvif_poll, 692 XENVIF_NAPI_WEIGHT); 693 694 queue->stalled = true; 695 696 task = kthread_run(xenvif_kthread_guest_rx, queue, 697 "%s-guest-rx", queue->name); 698 if (IS_ERR(task)) 699 goto kthread_err; 700 queue->task = task; 701 702 task = kthread_run(xenvif_dealloc_kthread, queue, 703 "%s-dealloc", queue->name); 704 if (IS_ERR(task)) 705 goto kthread_err; 706 queue->dealloc_task = task; 707 708 if (tx_evtchn == rx_evtchn) { 709 /* feature-split-event-channels == 0 */ 710 err = bind_interdomain_evtchn_to_irqhandler( 711 queue->vif->domid, tx_evtchn, xenvif_interrupt, 0, 712 queue->name, queue); 713 if (err < 0) 714 goto err; 715 queue->tx_irq = queue->rx_irq = err; 716 disable_irq(queue->tx_irq); 717 } else { 718 /* feature-split-event-channels == 1 */ 719 snprintf(queue->tx_irq_name, sizeof(queue->tx_irq_name), 720 "%s-tx", queue->name); 721 err = bind_interdomain_evtchn_to_irqhandler( 722 queue->vif->domid, tx_evtchn, xenvif_tx_interrupt, 0, 723 queue->tx_irq_name, queue); 724 if (err < 0) 725 goto err; 726 queue->tx_irq = err; 727 disable_irq(queue->tx_irq); 728 729 snprintf(queue->rx_irq_name, sizeof(queue->rx_irq_name), 730 "%s-rx", queue->name); 731 err = bind_interdomain_evtchn_to_irqhandler( 732 queue->vif->domid, rx_evtchn, xenvif_rx_interrupt, 0, 733 queue->rx_irq_name, queue); 734 if (err < 0) 735 goto err; 736 queue->rx_irq = err; 737 disable_irq(queue->rx_irq); 738 } 739 740 return 0; 741 742 kthread_err: 743 pr_warn("Could not allocate kthread for %s\n", queue->name); 744 err = PTR_ERR(task); 745 err: 746 xenvif_disconnect_queue(queue); 747 return err; 748 } 749 750 void xenvif_carrier_off(struct xenvif *vif) 751 { 752 struct net_device *dev = vif->dev; 753 754 rtnl_lock(); 755 if (test_and_clear_bit(VIF_STATUS_CONNECTED, &vif->status)) { 756 netif_carrier_off(dev); /* discard queued packets */ 757 if (netif_running(dev)) 758 xenvif_down(vif); 759 } 760 rtnl_unlock(); 761 } 762 763 void xenvif_disconnect_data(struct xenvif *vif) 764 { 765 struct xenvif_queue *queue = NULL; 766 unsigned int num_queues = vif->num_queues; 767 unsigned int queue_index; 768 769 xenvif_carrier_off(vif); 770 771 for (queue_index = 0; queue_index < num_queues; ++queue_index) { 772 queue = &vif->queues[queue_index]; 773 774 xenvif_disconnect_queue(queue); 775 } 776 777 xenvif_mcast_addr_list_free(vif); 778 } 779 780 void xenvif_disconnect_ctrl(struct xenvif *vif) 781 { 782 if (vif->ctrl_irq) { 783 xenvif_deinit_hash(vif); 784 unbind_from_irqhandler(vif->ctrl_irq, vif); 785 vif->ctrl_irq = 0; 786 } 787 788 if (vif->ctrl.sring) { 789 xenbus_unmap_ring_vfree(xenvif_to_xenbus_device(vif), 790 vif->ctrl.sring); 791 vif->ctrl.sring = NULL; 792 } 793 } 794 795 /* Reverse the relevant parts of xenvif_init_queue(). 796 * Used for queue teardown from xenvif_free(), and on the 797 * error handling paths in xenbus.c:connect(). 798 */ 799 void xenvif_deinit_queue(struct xenvif_queue *queue) 800 { 801 gnttab_free_pages(MAX_PENDING_REQS, queue->mmap_pages); 802 } 803 804 void xenvif_free(struct xenvif *vif) 805 { 806 struct xenvif_queue *queues = vif->queues; 807 unsigned int num_queues = vif->num_queues; 808 unsigned int queue_index; 809 810 unregister_netdev(vif->dev); 811 free_netdev(vif->dev); 812 813 for (queue_index = 0; queue_index < num_queues; ++queue_index) 814 xenvif_deinit_queue(&queues[queue_index]); 815 vfree(queues); 816 817 module_put(THIS_MODULE); 818 } 819