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/* Number of bytes allowed on the internal guest Rx queue. */ 45#define XENVIF_RX_QUEUE_BYTES (XEN_NETIF_RX_RING_SIZE/2 * PAGE_SIZE) 46 47/* This function is used to set SKBFL_ZEROCOPY_ENABLE as well as 48 * increasing the inflight counter. We need to increase the inflight 49 * counter because core driver calls into xenvif_zerocopy_callback 50 * which calls xenvif_skb_zerocopy_complete. 51 */ 52void xenvif_skb_zerocopy_prepare(struct xenvif_queue *queue, 53 struct sk_buff *skb) 54{ 55 skb_shinfo(skb)->flags |= SKBFL_ZEROCOPY_ENABLE; 56 atomic_inc(&queue->inflight_packets); 57} 58 59void xenvif_skb_zerocopy_complete(struct xenvif_queue *queue) 60{ 61 atomic_dec(&queue->inflight_packets); 62 63 /* Wake the dealloc thread _after_ decrementing inflight_packets so 64 * that if kthread_stop() has already been called, the dealloc thread 65 * does not wait forever with nothing to wake it. 66 */ 67 wake_up(&queue->dealloc_wq); 68} 69 70static int xenvif_schedulable(struct xenvif *vif) 71{ 72 return netif_running(vif->dev) && 73 test_bit(VIF_STATUS_CONNECTED, &vif->status) && 74 !vif->disabled; 75} 76 77static bool xenvif_handle_tx_interrupt(struct xenvif_queue *queue) 78{ 79 bool rc; 80 81 rc = RING_HAS_UNCONSUMED_REQUESTS(&queue->tx); 82 if (rc) 83 napi_schedule(&queue->napi); 84 return rc; 85} 86 87static irqreturn_t xenvif_tx_interrupt(int irq, void *dev_id) 88{ 89 struct xenvif_queue *queue = dev_id; 90 int old; 91 92 old = atomic_fetch_or(NETBK_TX_EOI, &queue->eoi_pending); 93 WARN(old & NETBK_TX_EOI, "Interrupt while EOI pending\n"); 94 95 if (!xenvif_handle_tx_interrupt(queue)) { 96 atomic_andnot(NETBK_TX_EOI, &queue->eoi_pending); 97 xen_irq_lateeoi(irq, XEN_EOI_FLAG_SPURIOUS); 98 } 99 100 return IRQ_HANDLED; 101} 102 103static int xenvif_poll(struct napi_struct *napi, int budget) 104{ 105 struct xenvif_queue *queue = 106 container_of(napi, struct xenvif_queue, napi); 107 int work_done; 108 109 /* This vif is rogue, we pretend we've there is nothing to do 110 * for this vif to deschedule it from NAPI. But this interface 111 * will be turned off in thread context later. 112 */ 113 if (unlikely(queue->vif->disabled)) { 114 napi_complete(napi); 115 return 0; 116 } 117 118 work_done = xenvif_tx_action(queue, budget); 119 120 if (work_done < budget) { 121 napi_complete_done(napi, work_done); 122 /* If the queue is rate-limited, it shall be 123 * rescheduled in the timer callback. 124 */ 125 if (likely(!queue->rate_limited)) 126 xenvif_napi_schedule_or_enable_events(queue); 127 } 128 129 return work_done; 130} 131 132static bool xenvif_handle_rx_interrupt(struct xenvif_queue *queue) 133{ 134 bool rc; 135 136 rc = xenvif_have_rx_work(queue, false); 137 if (rc) 138 xenvif_kick_thread(queue); 139 return rc; 140} 141 142static irqreturn_t xenvif_rx_interrupt(int irq, void *dev_id) 143{ 144 struct xenvif_queue *queue = dev_id; 145 int old; 146 147 old = atomic_fetch_or(NETBK_RX_EOI, &queue->eoi_pending); 148 WARN(old & NETBK_RX_EOI, "Interrupt while EOI pending\n"); 149 150 if (!xenvif_handle_rx_interrupt(queue)) { 151 atomic_andnot(NETBK_RX_EOI, &queue->eoi_pending); 152 xen_irq_lateeoi(irq, XEN_EOI_FLAG_SPURIOUS); 153 } 154 155 return IRQ_HANDLED; 156} 157 158irqreturn_t xenvif_interrupt(int irq, void *dev_id) 159{ 160 struct xenvif_queue *queue = dev_id; 161 int old; 162 bool has_rx, has_tx; 163 164 old = atomic_fetch_or(NETBK_COMMON_EOI, &queue->eoi_pending); 165 WARN(old, "Interrupt while EOI pending\n"); 166 167 has_tx = xenvif_handle_tx_interrupt(queue); 168 has_rx = xenvif_handle_rx_interrupt(queue); 169 170 if (!has_rx && !has_tx) { 171 atomic_andnot(NETBK_COMMON_EOI, &queue->eoi_pending); 172 xen_irq_lateeoi(irq, XEN_EOI_FLAG_SPURIOUS); 173 } 174 175 return IRQ_HANDLED; 176} 177 178static u16 xenvif_select_queue(struct net_device *dev, struct sk_buff *skb, 179 struct net_device *sb_dev) 180{ 181 struct xenvif *vif = netdev_priv(dev); 182 unsigned int size = vif->hash.size; 183 unsigned int num_queues; 184 185 /* If queues are not set up internally - always return 0 186 * as the packet going to be dropped anyway */ 187 num_queues = READ_ONCE(vif->num_queues); 188 if (num_queues < 1) 189 return 0; 190 191 if (vif->hash.alg == XEN_NETIF_CTRL_HASH_ALGORITHM_NONE) 192 return netdev_pick_tx(dev, skb, NULL) % 193 dev->real_num_tx_queues; 194 195 xenvif_set_skb_hash(vif, skb); 196 197 if (size == 0) 198 return skb_get_hash_raw(skb) % dev->real_num_tx_queues; 199 200 return vif->hash.mapping[vif->hash.mapping_sel] 201 [skb_get_hash_raw(skb) % size]; 202} 203 204static netdev_tx_t 205xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev) 206{ 207 struct xenvif *vif = netdev_priv(dev); 208 struct xenvif_queue *queue = NULL; 209 unsigned int num_queues; 210 u16 index; 211 struct xenvif_rx_cb *cb; 212 213 BUG_ON(skb->dev != dev); 214 215 /* Drop the packet if queues are not set up. 216 * This handler should be called inside an RCU read section 217 * so we don't need to enter it here explicitly. 218 */ 219 num_queues = READ_ONCE(vif->num_queues); 220 if (num_queues < 1) 221 goto drop; 222 223 /* Obtain the queue to be used to transmit this packet */ 224 index = skb_get_queue_mapping(skb); 225 if (index >= num_queues) { 226 pr_warn_ratelimited("Invalid queue %hu for packet on interface %s\n", 227 index, vif->dev->name); 228 index %= num_queues; 229 } 230 queue = &vif->queues[index]; 231 232 /* Drop the packet if queue is not ready */ 233 if (queue->task == NULL || 234 queue->dealloc_task == NULL || 235 !xenvif_schedulable(vif)) 236 goto drop; 237 238 if (vif->multicast_control && skb->pkt_type == PACKET_MULTICAST) { 239 struct ethhdr *eth = (struct ethhdr *)skb->data; 240 241 if (!xenvif_mcast_match(vif, eth->h_dest)) 242 goto drop; 243 } 244 245 cb = XENVIF_RX_CB(skb); 246 cb->expires = jiffies + vif->drain_timeout; 247 248 /* If there is no hash algorithm configured then make sure there 249 * is no hash information in the socket buffer otherwise it 250 * would be incorrectly forwarded to the frontend. 251 */ 252 if (vif->hash.alg == XEN_NETIF_CTRL_HASH_ALGORITHM_NONE) 253 skb_clear_hash(skb); 254 255 /* timestamp packet in software */ 256 skb_tx_timestamp(skb); 257 258 if (!xenvif_rx_queue_tail(queue, skb)) 259 goto drop; 260 261 xenvif_kick_thread(queue); 262 263 return NETDEV_TX_OK; 264 265 drop: 266 vif->dev->stats.tx_dropped++; 267 dev_kfree_skb_any(skb); 268 return NETDEV_TX_OK; 269} 270 271static struct net_device_stats *xenvif_get_stats(struct net_device *dev) 272{ 273 struct xenvif *vif = netdev_priv(dev); 274 struct xenvif_queue *queue = NULL; 275 unsigned int num_queues; 276 u64 rx_bytes = 0; 277 u64 rx_packets = 0; 278 u64 tx_bytes = 0; 279 u64 tx_packets = 0; 280 unsigned int index; 281 282 rcu_read_lock(); 283 num_queues = READ_ONCE(vif->num_queues); 284 285 /* Aggregate tx and rx stats from each queue */ 286 for (index = 0; index < num_queues; ++index) { 287 queue = &vif->queues[index]; 288 rx_bytes += queue->stats.rx_bytes; 289 rx_packets += queue->stats.rx_packets; 290 tx_bytes += queue->stats.tx_bytes; 291 tx_packets += queue->stats.tx_packets; 292 } 293 294 rcu_read_unlock(); 295 296 vif->dev->stats.rx_bytes = rx_bytes; 297 vif->dev->stats.rx_packets = rx_packets; 298 vif->dev->stats.tx_bytes = tx_bytes; 299 vif->dev->stats.tx_packets = tx_packets; 300 301 return &vif->dev->stats; 302} 303 304static void xenvif_up(struct xenvif *vif) 305{ 306 struct xenvif_queue *queue = NULL; 307 unsigned int num_queues = vif->num_queues; 308 unsigned int queue_index; 309 310 for (queue_index = 0; queue_index < num_queues; ++queue_index) { 311 queue = &vif->queues[queue_index]; 312 napi_enable(&queue->napi); 313 enable_irq(queue->tx_irq); 314 if (queue->tx_irq != queue->rx_irq) 315 enable_irq(queue->rx_irq); 316 xenvif_napi_schedule_or_enable_events(queue); 317 } 318} 319 320static void xenvif_down(struct xenvif *vif) 321{ 322 struct xenvif_queue *queue = NULL; 323 unsigned int num_queues = vif->num_queues; 324 unsigned int queue_index; 325 326 for (queue_index = 0; queue_index < num_queues; ++queue_index) { 327 queue = &vif->queues[queue_index]; 328 disable_irq(queue->tx_irq); 329 if (queue->tx_irq != queue->rx_irq) 330 disable_irq(queue->rx_irq); 331 napi_disable(&queue->napi); 332 del_timer_sync(&queue->credit_timeout); 333 } 334} 335 336static int xenvif_open(struct net_device *dev) 337{ 338 struct xenvif *vif = netdev_priv(dev); 339 if (test_bit(VIF_STATUS_CONNECTED, &vif->status)) 340 xenvif_up(vif); 341 netif_tx_start_all_queues(dev); 342 return 0; 343} 344 345static int xenvif_close(struct net_device *dev) 346{ 347 struct xenvif *vif = netdev_priv(dev); 348 if (test_bit(VIF_STATUS_CONNECTED, &vif->status)) 349 xenvif_down(vif); 350 netif_tx_stop_all_queues(dev); 351 return 0; 352} 353 354static int xenvif_change_mtu(struct net_device *dev, int mtu) 355{ 356 struct xenvif *vif = netdev_priv(dev); 357 int max = vif->can_sg ? ETH_MAX_MTU - VLAN_ETH_HLEN : ETH_DATA_LEN; 358 359 if (mtu > max) 360 return -EINVAL; 361 dev->mtu = mtu; 362 return 0; 363} 364 365static netdev_features_t xenvif_fix_features(struct net_device *dev, 366 netdev_features_t features) 367{ 368 struct xenvif *vif = netdev_priv(dev); 369 370 if (!vif->can_sg) 371 features &= ~NETIF_F_SG; 372 if (~(vif->gso_mask) & GSO_BIT(TCPV4)) 373 features &= ~NETIF_F_TSO; 374 if (~(vif->gso_mask) & GSO_BIT(TCPV6)) 375 features &= ~NETIF_F_TSO6; 376 if (!vif->ip_csum) 377 features &= ~NETIF_F_IP_CSUM; 378 if (!vif->ipv6_csum) 379 features &= ~NETIF_F_IPV6_CSUM; 380 381 return features; 382} 383 384static const struct xenvif_stat { 385 char name[ETH_GSTRING_LEN]; 386 u16 offset; 387} xenvif_stats[] = { 388 { 389 "rx_gso_checksum_fixup", 390 offsetof(struct xenvif_stats, rx_gso_checksum_fixup) 391 }, 392 /* If (sent != success + fail), there are probably packets never 393 * freed up properly! 394 */ 395 { 396 "tx_zerocopy_sent", 397 offsetof(struct xenvif_stats, tx_zerocopy_sent), 398 }, 399 { 400 "tx_zerocopy_success", 401 offsetof(struct xenvif_stats, tx_zerocopy_success), 402 }, 403 { 404 "tx_zerocopy_fail", 405 offsetof(struct xenvif_stats, tx_zerocopy_fail) 406 }, 407 /* Number of packets exceeding MAX_SKB_FRAG slots. You should use 408 * a guest with the same MAX_SKB_FRAG 409 */ 410 { 411 "tx_frag_overflow", 412 offsetof(struct xenvif_stats, tx_frag_overflow) 413 }, 414}; 415 416static int xenvif_get_sset_count(struct net_device *dev, int string_set) 417{ 418 switch (string_set) { 419 case ETH_SS_STATS: 420 return ARRAY_SIZE(xenvif_stats); 421 default: 422 return -EINVAL; 423 } 424} 425 426static void xenvif_get_ethtool_stats(struct net_device *dev, 427 struct ethtool_stats *stats, u64 * data) 428{ 429 struct xenvif *vif = netdev_priv(dev); 430 unsigned int num_queues; 431 int i; 432 unsigned int queue_index; 433 434 rcu_read_lock(); 435 num_queues = READ_ONCE(vif->num_queues); 436 437 for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++) { 438 unsigned long accum = 0; 439 for (queue_index = 0; queue_index < num_queues; ++queue_index) { 440 void *vif_stats = &vif->queues[queue_index].stats; 441 accum += *(unsigned long *)(vif_stats + xenvif_stats[i].offset); 442 } 443 data[i] = accum; 444 } 445 446 rcu_read_unlock(); 447} 448 449static void xenvif_get_strings(struct net_device *dev, u32 stringset, u8 * data) 450{ 451 int i; 452 453 switch (stringset) { 454 case ETH_SS_STATS: 455 for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++) 456 memcpy(data + i * ETH_GSTRING_LEN, 457 xenvif_stats[i].name, ETH_GSTRING_LEN); 458 break; 459 } 460} 461 462static const struct ethtool_ops xenvif_ethtool_ops = { 463 .get_link = ethtool_op_get_link, 464 .get_ts_info = ethtool_op_get_ts_info, 465 .get_sset_count = xenvif_get_sset_count, 466 .get_ethtool_stats = xenvif_get_ethtool_stats, 467 .get_strings = xenvif_get_strings, 468}; 469 470static const struct net_device_ops xenvif_netdev_ops = { 471 .ndo_select_queue = xenvif_select_queue, 472 .ndo_start_xmit = xenvif_start_xmit, 473 .ndo_get_stats = xenvif_get_stats, 474 .ndo_open = xenvif_open, 475 .ndo_stop = xenvif_close, 476 .ndo_change_mtu = xenvif_change_mtu, 477 .ndo_fix_features = xenvif_fix_features, 478 .ndo_set_mac_address = eth_mac_addr, 479 .ndo_validate_addr = eth_validate_addr, 480}; 481 482struct xenvif *xenvif_alloc(struct device *parent, domid_t domid, 483 unsigned int handle) 484{ 485 static const u8 dummy_addr[ETH_ALEN] = { 486 0xfe, 0xff, 0xff, 0xff, 0xff, 0xff, 487 }; 488 int err; 489 struct net_device *dev; 490 struct xenvif *vif; 491 char name[IFNAMSIZ] = {}; 492 493 snprintf(name, IFNAMSIZ - 1, "vif%u.%u", domid, handle); 494 /* Allocate a netdev with the max. supported number of queues. 495 * When the guest selects the desired number, it will be updated 496 * via netif_set_real_num_*_queues(). 497 */ 498 dev = alloc_netdev_mq(sizeof(struct xenvif), name, NET_NAME_UNKNOWN, 499 ether_setup, xenvif_max_queues); 500 if (dev == NULL) { 501 pr_warn("Could not allocate netdev for %s\n", name); 502 return ERR_PTR(-ENOMEM); 503 } 504 505 SET_NETDEV_DEV(dev, parent); 506 507 vif = netdev_priv(dev); 508 509 vif->domid = domid; 510 vif->handle = handle; 511 vif->can_sg = 1; 512 vif->ip_csum = 1; 513 vif->dev = dev; 514 vif->disabled = false; 515 vif->drain_timeout = msecs_to_jiffies(rx_drain_timeout_msecs); 516 vif->stall_timeout = msecs_to_jiffies(rx_stall_timeout_msecs); 517 518 /* Start out with no queues. */ 519 vif->queues = NULL; 520 vif->num_queues = 0; 521 522 vif->xdp_headroom = 0; 523 524 spin_lock_init(&vif->lock); 525 INIT_LIST_HEAD(&vif->fe_mcast_addr); 526 527 dev->netdev_ops = &xenvif_netdev_ops; 528 dev->hw_features = NETIF_F_SG | 529 NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM | 530 NETIF_F_TSO | NETIF_F_TSO6 | NETIF_F_FRAGLIST; 531 dev->features = dev->hw_features | NETIF_F_RXCSUM; 532 dev->ethtool_ops = &xenvif_ethtool_ops; 533 534 dev->min_mtu = ETH_MIN_MTU; 535 dev->max_mtu = ETH_MAX_MTU - VLAN_ETH_HLEN; 536 537 /* 538 * Initialise a dummy MAC address. We choose the numerically 539 * largest non-broadcast address to prevent the address getting 540 * stolen by an Ethernet bridge for STP purposes. 541 * (FE:FF:FF:FF:FF:FF) 542 */ 543 eth_hw_addr_set(dev, dummy_addr); 544 545 netif_carrier_off(dev); 546 547 err = register_netdev(dev); 548 if (err) { 549 netdev_warn(dev, "Could not register device: err=%d\n", err); 550 free_netdev(dev); 551 return ERR_PTR(err); 552 } 553 554 netdev_dbg(dev, "Successfully created xenvif\n"); 555 556 __module_get(THIS_MODULE); 557 558 return vif; 559} 560 561int xenvif_init_queue(struct xenvif_queue *queue) 562{ 563 int err, i; 564 565 queue->credit_bytes = queue->remaining_credit = ~0UL; 566 queue->credit_usec = 0UL; 567 timer_setup(&queue->credit_timeout, xenvif_tx_credit_callback, 0); 568 queue->credit_window_start = get_jiffies_64(); 569 570 queue->rx_queue_max = XENVIF_RX_QUEUE_BYTES; 571 572 skb_queue_head_init(&queue->rx_queue); 573 skb_queue_head_init(&queue->tx_queue); 574 575 queue->pending_cons = 0; 576 queue->pending_prod = MAX_PENDING_REQS; 577 for (i = 0; i < MAX_PENDING_REQS; ++i) 578 queue->pending_ring[i] = i; 579 580 spin_lock_init(&queue->callback_lock); 581 spin_lock_init(&queue->response_lock); 582 583 /* If ballooning is disabled, this will consume real memory, so you 584 * better enable it. The long term solution would be to use just a 585 * bunch of valid page descriptors, without dependency on ballooning 586 */ 587 err = gnttab_alloc_pages(MAX_PENDING_REQS, 588 queue->mmap_pages); 589 if (err) { 590 netdev_err(queue->vif->dev, "Could not reserve mmap_pages\n"); 591 return -ENOMEM; 592 } 593 594 for (i = 0; i < MAX_PENDING_REQS; i++) { 595 queue->pending_tx_info[i].callback_struct = (struct ubuf_info_msgzc) 596 { { .callback = xenvif_zerocopy_callback }, 597 { { .ctx = NULL, 598 .desc = i } } }; 599 queue->grant_tx_handle[i] = NETBACK_INVALID_HANDLE; 600 } 601 602 return 0; 603} 604 605void xenvif_carrier_on(struct xenvif *vif) 606{ 607 rtnl_lock(); 608 if (!vif->can_sg && vif->dev->mtu > ETH_DATA_LEN) 609 dev_set_mtu(vif->dev, ETH_DATA_LEN); 610 netdev_update_features(vif->dev); 611 set_bit(VIF_STATUS_CONNECTED, &vif->status); 612 if (netif_running(vif->dev)) 613 xenvif_up(vif); 614 rtnl_unlock(); 615} 616 617int xenvif_connect_ctrl(struct xenvif *vif, grant_ref_t ring_ref, 618 unsigned int evtchn) 619{ 620 struct net_device *dev = vif->dev; 621 struct xenbus_device *xendev = xenvif_to_xenbus_device(vif); 622 void *addr; 623 struct xen_netif_ctrl_sring *shared; 624 RING_IDX rsp_prod, req_prod; 625 int err; 626 627 err = xenbus_map_ring_valloc(xendev, &ring_ref, 1, &addr); 628 if (err) 629 goto err; 630 631 shared = (struct xen_netif_ctrl_sring *)addr; 632 rsp_prod = READ_ONCE(shared->rsp_prod); 633 req_prod = READ_ONCE(shared->req_prod); 634 635 BACK_RING_ATTACH(&vif->ctrl, shared, rsp_prod, XEN_PAGE_SIZE); 636 637 err = -EIO; 638 if (req_prod - rsp_prod > RING_SIZE(&vif->ctrl)) 639 goto err_unmap; 640 641 err = bind_interdomain_evtchn_to_irq_lateeoi(xendev, evtchn); 642 if (err < 0) 643 goto err_unmap; 644 645 vif->ctrl_irq = err; 646 647 xenvif_init_hash(vif); 648 649 err = request_threaded_irq(vif->ctrl_irq, NULL, xenvif_ctrl_irq_fn, 650 IRQF_ONESHOT, "xen-netback-ctrl", vif); 651 if (err) { 652 pr_warn("Could not setup irq handler for %s\n", dev->name); 653 goto err_deinit; 654 } 655 656 return 0; 657 658err_deinit: 659 xenvif_deinit_hash(vif); 660 unbind_from_irqhandler(vif->ctrl_irq, vif); 661 vif->ctrl_irq = 0; 662 663err_unmap: 664 xenbus_unmap_ring_vfree(xendev, vif->ctrl.sring); 665 vif->ctrl.sring = NULL; 666 667err: 668 return err; 669} 670 671static void xenvif_disconnect_queue(struct xenvif_queue *queue) 672{ 673 if (queue->task) { 674 kthread_stop_put(queue->task); 675 queue->task = NULL; 676 } 677 678 if (queue->dealloc_task) { 679 kthread_stop(queue->dealloc_task); 680 queue->dealloc_task = NULL; 681 } 682 683 if (queue->napi.poll) { 684 netif_napi_del(&queue->napi); 685 queue->napi.poll = NULL; 686 } 687 688 if (queue->tx_irq) { 689 unbind_from_irqhandler(queue->tx_irq, queue); 690 if (queue->tx_irq == queue->rx_irq) 691 queue->rx_irq = 0; 692 queue->tx_irq = 0; 693 } 694 695 if (queue->rx_irq) { 696 unbind_from_irqhandler(queue->rx_irq, queue); 697 queue->rx_irq = 0; 698 } 699 700 xenvif_unmap_frontend_data_rings(queue); 701} 702 703int xenvif_connect_data(struct xenvif_queue *queue, 704 unsigned long tx_ring_ref, 705 unsigned long rx_ring_ref, 706 unsigned int tx_evtchn, 707 unsigned int rx_evtchn) 708{ 709 struct xenbus_device *dev = xenvif_to_xenbus_device(queue->vif); 710 struct task_struct *task; 711 int err; 712 713 BUG_ON(queue->tx_irq); 714 BUG_ON(queue->task); 715 BUG_ON(queue->dealloc_task); 716 717 err = xenvif_map_frontend_data_rings(queue, tx_ring_ref, 718 rx_ring_ref); 719 if (err < 0) 720 goto err; 721 722 init_waitqueue_head(&queue->wq); 723 init_waitqueue_head(&queue->dealloc_wq); 724 atomic_set(&queue->inflight_packets, 0); 725 726 netif_napi_add(queue->vif->dev, &queue->napi, xenvif_poll); 727 728 queue->stalled = true; 729 730 task = kthread_run(xenvif_kthread_guest_rx, queue, 731 "%s-guest-rx", queue->name); 732 if (IS_ERR(task)) 733 goto kthread_err; 734 queue->task = task; 735 /* 736 * Take a reference to the task in order to prevent it from being freed 737 * if the thread function returns before kthread_stop is called. 738 */ 739 get_task_struct(task); 740 741 task = kthread_run(xenvif_dealloc_kthread, queue, 742 "%s-dealloc", queue->name); 743 if (IS_ERR(task)) 744 goto kthread_err; 745 queue->dealloc_task = task; 746 747 if (tx_evtchn == rx_evtchn) { 748 /* feature-split-event-channels == 0 */ 749 err = bind_interdomain_evtchn_to_irqhandler_lateeoi( 750 dev, tx_evtchn, xenvif_interrupt, 0, 751 queue->name, queue); 752 if (err < 0) 753 goto err; 754 queue->tx_irq = queue->rx_irq = err; 755 disable_irq(queue->tx_irq); 756 } else { 757 /* feature-split-event-channels == 1 */ 758 snprintf(queue->tx_irq_name, sizeof(queue->tx_irq_name), 759 "%s-tx", queue->name); 760 err = bind_interdomain_evtchn_to_irqhandler_lateeoi( 761 dev, tx_evtchn, xenvif_tx_interrupt, 0, 762 queue->tx_irq_name, queue); 763 if (err < 0) 764 goto err; 765 queue->tx_irq = err; 766 disable_irq(queue->tx_irq); 767 768 snprintf(queue->rx_irq_name, sizeof(queue->rx_irq_name), 769 "%s-rx", queue->name); 770 err = bind_interdomain_evtchn_to_irqhandler_lateeoi( 771 dev, rx_evtchn, xenvif_rx_interrupt, 0, 772 queue->rx_irq_name, queue); 773 if (err < 0) 774 goto err; 775 queue->rx_irq = err; 776 disable_irq(queue->rx_irq); 777 } 778 779 return 0; 780 781kthread_err: 782 pr_warn("Could not allocate kthread for %s\n", queue->name); 783 err = PTR_ERR(task); 784err: 785 xenvif_disconnect_queue(queue); 786 return err; 787} 788 789void xenvif_carrier_off(struct xenvif *vif) 790{ 791 struct net_device *dev = vif->dev; 792 793 rtnl_lock(); 794 if (test_and_clear_bit(VIF_STATUS_CONNECTED, &vif->status)) { 795 netif_carrier_off(dev); /* discard queued packets */ 796 if (netif_running(dev)) 797 xenvif_down(vif); 798 } 799 rtnl_unlock(); 800} 801 802void xenvif_disconnect_data(struct xenvif *vif) 803{ 804 struct xenvif_queue *queue = NULL; 805 unsigned int num_queues = vif->num_queues; 806 unsigned int queue_index; 807 808 xenvif_carrier_off(vif); 809 810 for (queue_index = 0; queue_index < num_queues; ++queue_index) { 811 queue = &vif->queues[queue_index]; 812 813 xenvif_disconnect_queue(queue); 814 } 815 816 xenvif_mcast_addr_list_free(vif); 817} 818 819void xenvif_disconnect_ctrl(struct xenvif *vif) 820{ 821 if (vif->ctrl_irq) { 822 xenvif_deinit_hash(vif); 823 unbind_from_irqhandler(vif->ctrl_irq, vif); 824 vif->ctrl_irq = 0; 825 } 826 827 if (vif->ctrl.sring) { 828 xenbus_unmap_ring_vfree(xenvif_to_xenbus_device(vif), 829 vif->ctrl.sring); 830 vif->ctrl.sring = NULL; 831 } 832} 833 834/* Reverse the relevant parts of xenvif_init_queue(). 835 * Used for queue teardown from xenvif_free(), and on the 836 * error handling paths in xenbus.c:connect(). 837 */ 838void xenvif_deinit_queue(struct xenvif_queue *queue) 839{ 840 gnttab_free_pages(MAX_PENDING_REQS, queue->mmap_pages); 841} 842 843void xenvif_free(struct xenvif *vif) 844{ 845 struct xenvif_queue *queues = vif->queues; 846 unsigned int num_queues = vif->num_queues; 847 unsigned int queue_index; 848 849 unregister_netdev(vif->dev); 850 free_netdev(vif->dev); 851 852 for (queue_index = 0; queue_index < num_queues; ++queue_index) 853 xenvif_deinit_queue(&queues[queue_index]); 854 vfree(queues); 855 856 module_put(THIS_MODULE); 857} 858