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 bool xenvif_handle_tx_interrupt(struct xenvif_queue *queue) 81 { 82 bool rc; 83 84 rc = RING_HAS_UNCONSUMED_REQUESTS(&queue->tx); 85 if (rc) 86 napi_schedule(&queue->napi); 87 return rc; 88 } 89 90 static irqreturn_t xenvif_tx_interrupt(int irq, void *dev_id) 91 { 92 struct xenvif_queue *queue = dev_id; 93 int old; 94 95 old = atomic_fetch_or(NETBK_TX_EOI, &queue->eoi_pending); 96 WARN(old & NETBK_TX_EOI, "Interrupt while EOI pending\n"); 97 98 if (!xenvif_handle_tx_interrupt(queue)) { 99 atomic_andnot(NETBK_TX_EOI, &queue->eoi_pending); 100 xen_irq_lateeoi(irq, XEN_EOI_FLAG_SPURIOUS); 101 } 102 103 return IRQ_HANDLED; 104 } 105 106 static int xenvif_poll(struct napi_struct *napi, int budget) 107 { 108 struct xenvif_queue *queue = 109 container_of(napi, struct xenvif_queue, napi); 110 int work_done; 111 112 /* This vif is rogue, we pretend we've there is nothing to do 113 * for this vif to deschedule it from NAPI. But this interface 114 * will be turned off in thread context later. 115 */ 116 if (unlikely(queue->vif->disabled)) { 117 napi_complete(napi); 118 return 0; 119 } 120 121 work_done = xenvif_tx_action(queue, budget); 122 123 if (work_done < budget) { 124 napi_complete_done(napi, work_done); 125 /* If the queue is rate-limited, it shall be 126 * rescheduled in the timer callback. 127 */ 128 if (likely(!queue->rate_limited)) 129 xenvif_napi_schedule_or_enable_events(queue); 130 } 131 132 return work_done; 133 } 134 135 static bool xenvif_handle_rx_interrupt(struct xenvif_queue *queue) 136 { 137 bool rc; 138 139 rc = xenvif_have_rx_work(queue, false); 140 if (rc) 141 xenvif_kick_thread(queue); 142 return rc; 143 } 144 145 static irqreturn_t xenvif_rx_interrupt(int irq, void *dev_id) 146 { 147 struct xenvif_queue *queue = dev_id; 148 int old; 149 150 old = atomic_fetch_or(NETBK_RX_EOI, &queue->eoi_pending); 151 WARN(old & NETBK_RX_EOI, "Interrupt while EOI pending\n"); 152 153 if (!xenvif_handle_rx_interrupt(queue)) { 154 atomic_andnot(NETBK_RX_EOI, &queue->eoi_pending); 155 xen_irq_lateeoi(irq, XEN_EOI_FLAG_SPURIOUS); 156 } 157 158 return IRQ_HANDLED; 159 } 160 161 irqreturn_t xenvif_interrupt(int irq, void *dev_id) 162 { 163 struct xenvif_queue *queue = dev_id; 164 int old; 165 166 old = atomic_fetch_or(NETBK_COMMON_EOI, &queue->eoi_pending); 167 WARN(old, "Interrupt while EOI pending\n"); 168 169 /* Use bitwise or as we need to call both functions. */ 170 if ((!xenvif_handle_tx_interrupt(queue) | 171 !xenvif_handle_rx_interrupt(queue))) { 172 atomic_andnot(NETBK_COMMON_EOI, &queue->eoi_pending); 173 xen_irq_lateeoi(irq, XEN_EOI_FLAG_SPURIOUS); 174 } 175 176 return IRQ_HANDLED; 177 } 178 179 int xenvif_queue_stopped(struct xenvif_queue *queue) 180 { 181 struct net_device *dev = queue->vif->dev; 182 unsigned int id = queue->id; 183 return netif_tx_queue_stopped(netdev_get_tx_queue(dev, id)); 184 } 185 186 void xenvif_wake_queue(struct xenvif_queue *queue) 187 { 188 struct net_device *dev = queue->vif->dev; 189 unsigned int id = queue->id; 190 netif_tx_wake_queue(netdev_get_tx_queue(dev, id)); 191 } 192 193 static u16 xenvif_select_queue(struct net_device *dev, struct sk_buff *skb, 194 struct net_device *sb_dev) 195 { 196 struct xenvif *vif = netdev_priv(dev); 197 unsigned int size = vif->hash.size; 198 unsigned int num_queues; 199 200 /* If queues are not set up internally - always return 0 201 * as the packet going to be dropped anyway */ 202 num_queues = READ_ONCE(vif->num_queues); 203 if (num_queues < 1) 204 return 0; 205 206 if (vif->hash.alg == XEN_NETIF_CTRL_HASH_ALGORITHM_NONE) 207 return netdev_pick_tx(dev, skb, NULL) % 208 dev->real_num_tx_queues; 209 210 xenvif_set_skb_hash(vif, skb); 211 212 if (size == 0) 213 return skb_get_hash_raw(skb) % dev->real_num_tx_queues; 214 215 return vif->hash.mapping[vif->hash.mapping_sel] 216 [skb_get_hash_raw(skb) % size]; 217 } 218 219 static netdev_tx_t 220 xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev) 221 { 222 struct xenvif *vif = netdev_priv(dev); 223 struct xenvif_queue *queue = NULL; 224 unsigned int num_queues; 225 u16 index; 226 struct xenvif_rx_cb *cb; 227 228 BUG_ON(skb->dev != dev); 229 230 /* Drop the packet if queues are not set up. 231 * This handler should be called inside an RCU read section 232 * so we don't need to enter it here explicitly. 233 */ 234 num_queues = READ_ONCE(vif->num_queues); 235 if (num_queues < 1) 236 goto drop; 237 238 /* Obtain the queue to be used to transmit this packet */ 239 index = skb_get_queue_mapping(skb); 240 if (index >= num_queues) { 241 pr_warn_ratelimited("Invalid queue %hu for packet on interface %s\n", 242 index, vif->dev->name); 243 index %= num_queues; 244 } 245 queue = &vif->queues[index]; 246 247 /* Drop the packet if queue is not ready */ 248 if (queue->task == NULL || 249 queue->dealloc_task == NULL || 250 !xenvif_schedulable(vif)) 251 goto drop; 252 253 if (vif->multicast_control && skb->pkt_type == PACKET_MULTICAST) { 254 struct ethhdr *eth = (struct ethhdr *)skb->data; 255 256 if (!xenvif_mcast_match(vif, eth->h_dest)) 257 goto drop; 258 } 259 260 cb = XENVIF_RX_CB(skb); 261 cb->expires = jiffies + vif->drain_timeout; 262 263 /* If there is no hash algorithm configured then make sure there 264 * is no hash information in the socket buffer otherwise it 265 * would be incorrectly forwarded to the frontend. 266 */ 267 if (vif->hash.alg == XEN_NETIF_CTRL_HASH_ALGORITHM_NONE) 268 skb_clear_hash(skb); 269 270 xenvif_rx_queue_tail(queue, skb); 271 xenvif_kick_thread(queue); 272 273 return NETDEV_TX_OK; 274 275 drop: 276 vif->dev->stats.tx_dropped++; 277 dev_kfree_skb(skb); 278 return NETDEV_TX_OK; 279 } 280 281 static struct net_device_stats *xenvif_get_stats(struct net_device *dev) 282 { 283 struct xenvif *vif = netdev_priv(dev); 284 struct xenvif_queue *queue = NULL; 285 unsigned int num_queues; 286 u64 rx_bytes = 0; 287 u64 rx_packets = 0; 288 u64 tx_bytes = 0; 289 u64 tx_packets = 0; 290 unsigned int index; 291 292 rcu_read_lock(); 293 num_queues = READ_ONCE(vif->num_queues); 294 295 /* Aggregate tx and rx stats from each queue */ 296 for (index = 0; index < num_queues; ++index) { 297 queue = &vif->queues[index]; 298 rx_bytes += queue->stats.rx_bytes; 299 rx_packets += queue->stats.rx_packets; 300 tx_bytes += queue->stats.tx_bytes; 301 tx_packets += queue->stats.tx_packets; 302 } 303 304 rcu_read_unlock(); 305 306 vif->dev->stats.rx_bytes = rx_bytes; 307 vif->dev->stats.rx_packets = rx_packets; 308 vif->dev->stats.tx_bytes = tx_bytes; 309 vif->dev->stats.tx_packets = tx_packets; 310 311 return &vif->dev->stats; 312 } 313 314 static void xenvif_up(struct xenvif *vif) 315 { 316 struct xenvif_queue *queue = NULL; 317 unsigned int num_queues = vif->num_queues; 318 unsigned int queue_index; 319 320 for (queue_index = 0; queue_index < num_queues; ++queue_index) { 321 queue = &vif->queues[queue_index]; 322 napi_enable(&queue->napi); 323 enable_irq(queue->tx_irq); 324 if (queue->tx_irq != queue->rx_irq) 325 enable_irq(queue->rx_irq); 326 xenvif_napi_schedule_or_enable_events(queue); 327 } 328 } 329 330 static void xenvif_down(struct xenvif *vif) 331 { 332 struct xenvif_queue *queue = NULL; 333 unsigned int num_queues = vif->num_queues; 334 unsigned int queue_index; 335 336 for (queue_index = 0; queue_index < num_queues; ++queue_index) { 337 queue = &vif->queues[queue_index]; 338 disable_irq(queue->tx_irq); 339 if (queue->tx_irq != queue->rx_irq) 340 disable_irq(queue->rx_irq); 341 napi_disable(&queue->napi); 342 del_timer_sync(&queue->credit_timeout); 343 } 344 } 345 346 static int xenvif_open(struct net_device *dev) 347 { 348 struct xenvif *vif = netdev_priv(dev); 349 if (test_bit(VIF_STATUS_CONNECTED, &vif->status)) 350 xenvif_up(vif); 351 netif_tx_start_all_queues(dev); 352 return 0; 353 } 354 355 static int xenvif_close(struct net_device *dev) 356 { 357 struct xenvif *vif = netdev_priv(dev); 358 if (test_bit(VIF_STATUS_CONNECTED, &vif->status)) 359 xenvif_down(vif); 360 netif_tx_stop_all_queues(dev); 361 return 0; 362 } 363 364 static int xenvif_change_mtu(struct net_device *dev, int mtu) 365 { 366 struct xenvif *vif = netdev_priv(dev); 367 int max = vif->can_sg ? ETH_MAX_MTU - VLAN_ETH_HLEN : ETH_DATA_LEN; 368 369 if (mtu > max) 370 return -EINVAL; 371 dev->mtu = mtu; 372 return 0; 373 } 374 375 static netdev_features_t xenvif_fix_features(struct net_device *dev, 376 netdev_features_t features) 377 { 378 struct xenvif *vif = netdev_priv(dev); 379 380 if (!vif->can_sg) 381 features &= ~NETIF_F_SG; 382 if (~(vif->gso_mask) & GSO_BIT(TCPV4)) 383 features &= ~NETIF_F_TSO; 384 if (~(vif->gso_mask) & GSO_BIT(TCPV6)) 385 features &= ~NETIF_F_TSO6; 386 if (!vif->ip_csum) 387 features &= ~NETIF_F_IP_CSUM; 388 if (!vif->ipv6_csum) 389 features &= ~NETIF_F_IPV6_CSUM; 390 391 return features; 392 } 393 394 static const struct xenvif_stat { 395 char name[ETH_GSTRING_LEN]; 396 u16 offset; 397 } xenvif_stats[] = { 398 { 399 "rx_gso_checksum_fixup", 400 offsetof(struct xenvif_stats, rx_gso_checksum_fixup) 401 }, 402 /* If (sent != success + fail), there are probably packets never 403 * freed up properly! 404 */ 405 { 406 "tx_zerocopy_sent", 407 offsetof(struct xenvif_stats, tx_zerocopy_sent), 408 }, 409 { 410 "tx_zerocopy_success", 411 offsetof(struct xenvif_stats, tx_zerocopy_success), 412 }, 413 { 414 "tx_zerocopy_fail", 415 offsetof(struct xenvif_stats, tx_zerocopy_fail) 416 }, 417 /* Number of packets exceeding MAX_SKB_FRAG slots. You should use 418 * a guest with the same MAX_SKB_FRAG 419 */ 420 { 421 "tx_frag_overflow", 422 offsetof(struct xenvif_stats, tx_frag_overflow) 423 }, 424 }; 425 426 static int xenvif_get_sset_count(struct net_device *dev, int string_set) 427 { 428 switch (string_set) { 429 case ETH_SS_STATS: 430 return ARRAY_SIZE(xenvif_stats); 431 default: 432 return -EINVAL; 433 } 434 } 435 436 static void xenvif_get_ethtool_stats(struct net_device *dev, 437 struct ethtool_stats *stats, u64 * data) 438 { 439 struct xenvif *vif = netdev_priv(dev); 440 unsigned int num_queues; 441 int i; 442 unsigned int queue_index; 443 444 rcu_read_lock(); 445 num_queues = READ_ONCE(vif->num_queues); 446 447 for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++) { 448 unsigned long accum = 0; 449 for (queue_index = 0; queue_index < num_queues; ++queue_index) { 450 void *vif_stats = &vif->queues[queue_index].stats; 451 accum += *(unsigned long *)(vif_stats + xenvif_stats[i].offset); 452 } 453 data[i] = accum; 454 } 455 456 rcu_read_unlock(); 457 } 458 459 static void xenvif_get_strings(struct net_device *dev, u32 stringset, u8 * data) 460 { 461 int i; 462 463 switch (stringset) { 464 case ETH_SS_STATS: 465 for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++) 466 memcpy(data + i * ETH_GSTRING_LEN, 467 xenvif_stats[i].name, ETH_GSTRING_LEN); 468 break; 469 } 470 } 471 472 static const struct ethtool_ops xenvif_ethtool_ops = { 473 .get_link = ethtool_op_get_link, 474 475 .get_sset_count = xenvif_get_sset_count, 476 .get_ethtool_stats = xenvif_get_ethtool_stats, 477 .get_strings = xenvif_get_strings, 478 }; 479 480 static const struct net_device_ops xenvif_netdev_ops = { 481 .ndo_select_queue = xenvif_select_queue, 482 .ndo_start_xmit = xenvif_start_xmit, 483 .ndo_get_stats = xenvif_get_stats, 484 .ndo_open = xenvif_open, 485 .ndo_stop = xenvif_close, 486 .ndo_change_mtu = xenvif_change_mtu, 487 .ndo_fix_features = xenvif_fix_features, 488 .ndo_set_mac_address = eth_mac_addr, 489 .ndo_validate_addr = eth_validate_addr, 490 }; 491 492 struct xenvif *xenvif_alloc(struct device *parent, domid_t domid, 493 unsigned int handle) 494 { 495 int err; 496 struct net_device *dev; 497 struct xenvif *vif; 498 char name[IFNAMSIZ] = {}; 499 500 snprintf(name, IFNAMSIZ - 1, "vif%u.%u", domid, handle); 501 /* Allocate a netdev with the max. supported number of queues. 502 * When the guest selects the desired number, it will be updated 503 * via netif_set_real_num_*_queues(). 504 */ 505 dev = alloc_netdev_mq(sizeof(struct xenvif), name, NET_NAME_UNKNOWN, 506 ether_setup, xenvif_max_queues); 507 if (dev == NULL) { 508 pr_warn("Could not allocate netdev for %s\n", name); 509 return ERR_PTR(-ENOMEM); 510 } 511 512 SET_NETDEV_DEV(dev, parent); 513 514 vif = netdev_priv(dev); 515 516 vif->domid = domid; 517 vif->handle = handle; 518 vif->can_sg = 1; 519 vif->ip_csum = 1; 520 vif->dev = dev; 521 vif->disabled = false; 522 vif->drain_timeout = msecs_to_jiffies(rx_drain_timeout_msecs); 523 vif->stall_timeout = msecs_to_jiffies(rx_stall_timeout_msecs); 524 525 /* Start out with no queues. */ 526 vif->queues = NULL; 527 vif->num_queues = 0; 528 529 vif->xdp_headroom = 0; 530 531 spin_lock_init(&vif->lock); 532 INIT_LIST_HEAD(&vif->fe_mcast_addr); 533 534 dev->netdev_ops = &xenvif_netdev_ops; 535 dev->hw_features = NETIF_F_SG | 536 NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM | 537 NETIF_F_TSO | NETIF_F_TSO6 | NETIF_F_FRAGLIST; 538 dev->features = dev->hw_features | NETIF_F_RXCSUM; 539 dev->ethtool_ops = &xenvif_ethtool_ops; 540 541 dev->tx_queue_len = XENVIF_QUEUE_LENGTH; 542 543 dev->min_mtu = ETH_MIN_MTU; 544 dev->max_mtu = ETH_MAX_MTU - VLAN_ETH_HLEN; 545 546 /* 547 * Initialise a dummy MAC address. We choose the numerically 548 * largest non-broadcast address to prevent the address getting 549 * stolen by an Ethernet bridge for STP purposes. 550 * (FE:FF:FF:FF:FF:FF) 551 */ 552 eth_broadcast_addr(dev->dev_addr); 553 dev->dev_addr[0] &= ~0x01; 554 555 netif_carrier_off(dev); 556 557 err = register_netdev(dev); 558 if (err) { 559 netdev_warn(dev, "Could not register device: err=%d\n", err); 560 free_netdev(dev); 561 return ERR_PTR(err); 562 } 563 564 netdev_dbg(dev, "Successfully created xenvif\n"); 565 566 __module_get(THIS_MODULE); 567 568 return vif; 569 } 570 571 int xenvif_init_queue(struct xenvif_queue *queue) 572 { 573 int err, i; 574 575 queue->credit_bytes = queue->remaining_credit = ~0UL; 576 queue->credit_usec = 0UL; 577 timer_setup(&queue->credit_timeout, xenvif_tx_credit_callback, 0); 578 queue->credit_window_start = get_jiffies_64(); 579 580 queue->rx_queue_max = XENVIF_RX_QUEUE_BYTES; 581 582 skb_queue_head_init(&queue->rx_queue); 583 skb_queue_head_init(&queue->tx_queue); 584 585 queue->pending_cons = 0; 586 queue->pending_prod = MAX_PENDING_REQS; 587 for (i = 0; i < MAX_PENDING_REQS; ++i) 588 queue->pending_ring[i] = i; 589 590 spin_lock_init(&queue->callback_lock); 591 spin_lock_init(&queue->response_lock); 592 593 /* If ballooning is disabled, this will consume real memory, so you 594 * better enable it. The long term solution would be to use just a 595 * bunch of valid page descriptors, without dependency on ballooning 596 */ 597 err = gnttab_alloc_pages(MAX_PENDING_REQS, 598 queue->mmap_pages); 599 if (err) { 600 netdev_err(queue->vif->dev, "Could not reserve mmap_pages\n"); 601 return -ENOMEM; 602 } 603 604 for (i = 0; i < MAX_PENDING_REQS; i++) { 605 queue->pending_tx_info[i].callback_struct = (struct ubuf_info) 606 { .callback = xenvif_zerocopy_callback, 607 { { .ctx = NULL, 608 .desc = i } } }; 609 queue->grant_tx_handle[i] = NETBACK_INVALID_HANDLE; 610 } 611 612 return 0; 613 } 614 615 void xenvif_carrier_on(struct xenvif *vif) 616 { 617 rtnl_lock(); 618 if (!vif->can_sg && vif->dev->mtu > ETH_DATA_LEN) 619 dev_set_mtu(vif->dev, ETH_DATA_LEN); 620 netdev_update_features(vif->dev); 621 set_bit(VIF_STATUS_CONNECTED, &vif->status); 622 if (netif_running(vif->dev)) 623 xenvif_up(vif); 624 rtnl_unlock(); 625 } 626 627 int xenvif_connect_ctrl(struct xenvif *vif, grant_ref_t ring_ref, 628 unsigned int evtchn) 629 { 630 struct net_device *dev = vif->dev; 631 void *addr; 632 struct xen_netif_ctrl_sring *shared; 633 RING_IDX rsp_prod, req_prod; 634 int err; 635 636 err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(vif), 637 &ring_ref, 1, &addr); 638 if (err) 639 goto err; 640 641 shared = (struct xen_netif_ctrl_sring *)addr; 642 rsp_prod = READ_ONCE(shared->rsp_prod); 643 req_prod = READ_ONCE(shared->req_prod); 644 645 BACK_RING_ATTACH(&vif->ctrl, shared, rsp_prod, XEN_PAGE_SIZE); 646 647 err = -EIO; 648 if (req_prod - rsp_prod > RING_SIZE(&vif->ctrl)) 649 goto err_unmap; 650 651 err = bind_interdomain_evtchn_to_irq_lateeoi(vif->domid, evtchn); 652 if (err < 0) 653 goto err_unmap; 654 655 vif->ctrl_irq = err; 656 657 xenvif_init_hash(vif); 658 659 err = request_threaded_irq(vif->ctrl_irq, NULL, xenvif_ctrl_irq_fn, 660 IRQF_ONESHOT, "xen-netback-ctrl", vif); 661 if (err) { 662 pr_warn("Could not setup irq handler for %s\n", dev->name); 663 goto err_deinit; 664 } 665 666 return 0; 667 668 err_deinit: 669 xenvif_deinit_hash(vif); 670 unbind_from_irqhandler(vif->ctrl_irq, vif); 671 vif->ctrl_irq = 0; 672 673 err_unmap: 674 xenbus_unmap_ring_vfree(xenvif_to_xenbus_device(vif), 675 vif->ctrl.sring); 676 vif->ctrl.sring = NULL; 677 678 err: 679 return err; 680 } 681 682 static void xenvif_disconnect_queue(struct xenvif_queue *queue) 683 { 684 if (queue->task) { 685 kthread_stop(queue->task); 686 queue->task = NULL; 687 } 688 689 if (queue->dealloc_task) { 690 kthread_stop(queue->dealloc_task); 691 queue->dealloc_task = NULL; 692 } 693 694 if (queue->napi.poll) { 695 netif_napi_del(&queue->napi); 696 queue->napi.poll = NULL; 697 } 698 699 if (queue->tx_irq) { 700 unbind_from_irqhandler(queue->tx_irq, queue); 701 if (queue->tx_irq == queue->rx_irq) 702 queue->rx_irq = 0; 703 queue->tx_irq = 0; 704 } 705 706 if (queue->rx_irq) { 707 unbind_from_irqhandler(queue->rx_irq, queue); 708 queue->rx_irq = 0; 709 } 710 711 xenvif_unmap_frontend_data_rings(queue); 712 } 713 714 int xenvif_connect_data(struct xenvif_queue *queue, 715 unsigned long tx_ring_ref, 716 unsigned long rx_ring_ref, 717 unsigned int tx_evtchn, 718 unsigned int rx_evtchn) 719 { 720 struct task_struct *task; 721 int err; 722 723 BUG_ON(queue->tx_irq); 724 BUG_ON(queue->task); 725 BUG_ON(queue->dealloc_task); 726 727 err = xenvif_map_frontend_data_rings(queue, tx_ring_ref, 728 rx_ring_ref); 729 if (err < 0) 730 goto err; 731 732 init_waitqueue_head(&queue->wq); 733 init_waitqueue_head(&queue->dealloc_wq); 734 atomic_set(&queue->inflight_packets, 0); 735 736 netif_napi_add(queue->vif->dev, &queue->napi, xenvif_poll, 737 XENVIF_NAPI_WEIGHT); 738 739 queue->stalled = true; 740 741 task = kthread_run(xenvif_kthread_guest_rx, queue, 742 "%s-guest-rx", queue->name); 743 if (IS_ERR(task)) 744 goto kthread_err; 745 queue->task = task; 746 747 task = kthread_run(xenvif_dealloc_kthread, queue, 748 "%s-dealloc", queue->name); 749 if (IS_ERR(task)) 750 goto kthread_err; 751 queue->dealloc_task = task; 752 753 if (tx_evtchn == rx_evtchn) { 754 /* feature-split-event-channels == 0 */ 755 err = bind_interdomain_evtchn_to_irqhandler_lateeoi( 756 queue->vif->domid, tx_evtchn, xenvif_interrupt, 0, 757 queue->name, queue); 758 if (err < 0) 759 goto err; 760 queue->tx_irq = queue->rx_irq = err; 761 disable_irq(queue->tx_irq); 762 } else { 763 /* feature-split-event-channels == 1 */ 764 snprintf(queue->tx_irq_name, sizeof(queue->tx_irq_name), 765 "%s-tx", queue->name); 766 err = bind_interdomain_evtchn_to_irqhandler_lateeoi( 767 queue->vif->domid, tx_evtchn, xenvif_tx_interrupt, 0, 768 queue->tx_irq_name, queue); 769 if (err < 0) 770 goto err; 771 queue->tx_irq = err; 772 disable_irq(queue->tx_irq); 773 774 snprintf(queue->rx_irq_name, sizeof(queue->rx_irq_name), 775 "%s-rx", queue->name); 776 err = bind_interdomain_evtchn_to_irqhandler_lateeoi( 777 queue->vif->domid, rx_evtchn, xenvif_rx_interrupt, 0, 778 queue->rx_irq_name, queue); 779 if (err < 0) 780 goto err; 781 queue->rx_irq = err; 782 disable_irq(queue->rx_irq); 783 } 784 785 return 0; 786 787 kthread_err: 788 pr_warn("Could not allocate kthread for %s\n", queue->name); 789 err = PTR_ERR(task); 790 err: 791 xenvif_disconnect_queue(queue); 792 return err; 793 } 794 795 void xenvif_carrier_off(struct xenvif *vif) 796 { 797 struct net_device *dev = vif->dev; 798 799 rtnl_lock(); 800 if (test_and_clear_bit(VIF_STATUS_CONNECTED, &vif->status)) { 801 netif_carrier_off(dev); /* discard queued packets */ 802 if (netif_running(dev)) 803 xenvif_down(vif); 804 } 805 rtnl_unlock(); 806 } 807 808 void xenvif_disconnect_data(struct xenvif *vif) 809 { 810 struct xenvif_queue *queue = NULL; 811 unsigned int num_queues = vif->num_queues; 812 unsigned int queue_index; 813 814 xenvif_carrier_off(vif); 815 816 for (queue_index = 0; queue_index < num_queues; ++queue_index) { 817 queue = &vif->queues[queue_index]; 818 819 xenvif_disconnect_queue(queue); 820 } 821 822 xenvif_mcast_addr_list_free(vif); 823 } 824 825 void xenvif_disconnect_ctrl(struct xenvif *vif) 826 { 827 if (vif->ctrl_irq) { 828 xenvif_deinit_hash(vif); 829 unbind_from_irqhandler(vif->ctrl_irq, vif); 830 vif->ctrl_irq = 0; 831 } 832 833 if (vif->ctrl.sring) { 834 xenbus_unmap_ring_vfree(xenvif_to_xenbus_device(vif), 835 vif->ctrl.sring); 836 vif->ctrl.sring = NULL; 837 } 838 } 839 840 /* Reverse the relevant parts of xenvif_init_queue(). 841 * Used for queue teardown from xenvif_free(), and on the 842 * error handling paths in xenbus.c:connect(). 843 */ 844 void xenvif_deinit_queue(struct xenvif_queue *queue) 845 { 846 gnttab_free_pages(MAX_PENDING_REQS, queue->mmap_pages); 847 } 848 849 void xenvif_free(struct xenvif *vif) 850 { 851 struct xenvif_queue *queues = vif->queues; 852 unsigned int num_queues = vif->num_queues; 853 unsigned int queue_index; 854 855 unregister_netdev(vif->dev); 856 free_netdev(vif->dev); 857 858 for (queue_index = 0; queue_index < num_queues; ++queue_index) 859 xenvif_deinit_queue(&queues[queue_index]); 860 vfree(queues); 861 862 module_put(THIS_MODULE); 863 } 864