| 1 | /* |
| 2 | * Virtual network driver for conversing with remote driver backends. |
| 3 | * |
| 4 | * Copyright (c) 2002-2005, K A Fraser |
| 5 | * Copyright (c) 2005, XenSource Ltd |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU General Public License version 2 |
| 9 | * as published by the Free Software Foundation; or, when distributed |
| 10 | * separately from the Linux kernel or incorporated into other |
| 11 | * software packages, subject to the following license: |
| 12 | * |
| 13 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 14 | * of this source file (the "Software"), to deal in the Software without |
| 15 | * restriction, including without limitation the rights to use, copy, modify, |
| 16 | * merge, publish, distribute, sublicense, and/or sell copies of the Software, |
| 17 | * and to permit persons to whom the Software is furnished to do so, subject to |
| 18 | * the following conditions: |
| 19 | * |
| 20 | * The above copyright notice and this permission notice shall be included in |
| 21 | * all copies or substantial portions of the Software. |
| 22 | * |
| 23 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 24 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 25 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| 26 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 27 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
| 28 | * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS |
| 29 | * IN THE SOFTWARE. |
| 30 | */ |
| 31 | |
| 32 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| 33 | |
| 34 | #include <linux/module.h> |
| 35 | #include <linux/kernel.h> |
| 36 | #include <linux/netdevice.h> |
| 37 | #include <linux/etherdevice.h> |
| 38 | #include <linux/skbuff.h> |
| 39 | #include <linux/ethtool.h> |
| 40 | #include <linux/if_ether.h> |
| 41 | #include <net/tcp.h> |
| 42 | #include <linux/udp.h> |
| 43 | #include <linux/moduleparam.h> |
| 44 | #include <linux/mm.h> |
| 45 | #include <linux/slab.h> |
| 46 | #include <net/ip.h> |
| 47 | |
| 48 | #include <xen/xen.h> |
| 49 | #include <xen/xenbus.h> |
| 50 | #include <xen/events.h> |
| 51 | #include <xen/page.h> |
| 52 | #include <xen/platform_pci.h> |
| 53 | #include <xen/grant_table.h> |
| 54 | |
| 55 | #include <xen/interface/io/netif.h> |
| 56 | #include <xen/interface/memory.h> |
| 57 | #include <xen/interface/grant_table.h> |
| 58 | |
| 59 | /* Module parameters */ |
| 60 | static unsigned int xennet_max_queues; |
| 61 | module_param_named(max_queues, xennet_max_queues, uint, 0644); |
| 62 | MODULE_PARM_DESC(max_queues, |
| 63 | "Maximum number of queues per virtual interface"); |
| 64 | |
| 65 | static const struct ethtool_ops xennet_ethtool_ops; |
| 66 | |
| 67 | struct netfront_cb { |
| 68 | int pull_to; |
| 69 | }; |
| 70 | |
| 71 | #define NETFRONT_SKB_CB(skb) ((struct netfront_cb *)((skb)->cb)) |
| 72 | |
| 73 | #define RX_COPY_THRESHOLD 256 |
| 74 | |
| 75 | #define GRANT_INVALID_REF 0 |
| 76 | |
| 77 | #define NET_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, XEN_PAGE_SIZE) |
| 78 | #define NET_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, XEN_PAGE_SIZE) |
| 79 | |
| 80 | /* Minimum number of Rx slots (includes slot for GSO metadata). */ |
| 81 | #define NET_RX_SLOTS_MIN (XEN_NETIF_NR_SLOTS_MIN + 1) |
| 82 | |
| 83 | /* Queue name is interface name with "-qNNN" appended */ |
| 84 | #define QUEUE_NAME_SIZE (IFNAMSIZ + 6) |
| 85 | |
| 86 | /* IRQ name is queue name with "-tx" or "-rx" appended */ |
| 87 | #define IRQ_NAME_SIZE (QUEUE_NAME_SIZE + 3) |
| 88 | |
| 89 | struct netfront_stats { |
| 90 | u64 packets; |
| 91 | u64 bytes; |
| 92 | struct u64_stats_sync syncp; |
| 93 | }; |
| 94 | |
| 95 | struct netfront_info; |
| 96 | |
| 97 | struct netfront_queue { |
| 98 | unsigned int id; /* Queue ID, 0-based */ |
| 99 | char name[QUEUE_NAME_SIZE]; /* DEVNAME-qN */ |
| 100 | struct netfront_info *info; |
| 101 | |
| 102 | struct napi_struct napi; |
| 103 | |
| 104 | /* Split event channels support, tx_* == rx_* when using |
| 105 | * single event channel. |
| 106 | */ |
| 107 | unsigned int tx_evtchn, rx_evtchn; |
| 108 | unsigned int tx_irq, rx_irq; |
| 109 | /* Only used when split event channels support is enabled */ |
| 110 | char tx_irq_name[IRQ_NAME_SIZE]; /* DEVNAME-qN-tx */ |
| 111 | char rx_irq_name[IRQ_NAME_SIZE]; /* DEVNAME-qN-rx */ |
| 112 | |
| 113 | spinlock_t tx_lock; |
| 114 | struct xen_netif_tx_front_ring tx; |
| 115 | int tx_ring_ref; |
| 116 | |
| 117 | /* |
| 118 | * {tx,rx}_skbs store outstanding skbuffs. Free tx_skb entries |
| 119 | * are linked from tx_skb_freelist through skb_entry.link. |
| 120 | * |
| 121 | * NB. Freelist index entries are always going to be less than |
| 122 | * PAGE_OFFSET, whereas pointers to skbs will always be equal or |
| 123 | * greater than PAGE_OFFSET: we use this property to distinguish |
| 124 | * them. |
| 125 | */ |
| 126 | union skb_entry { |
| 127 | struct sk_buff *skb; |
| 128 | unsigned long link; |
| 129 | } tx_skbs[NET_TX_RING_SIZE]; |
| 130 | grant_ref_t gref_tx_head; |
| 131 | grant_ref_t grant_tx_ref[NET_TX_RING_SIZE]; |
| 132 | struct page *grant_tx_page[NET_TX_RING_SIZE]; |
| 133 | unsigned tx_skb_freelist; |
| 134 | |
| 135 | spinlock_t rx_lock ____cacheline_aligned_in_smp; |
| 136 | struct xen_netif_rx_front_ring rx; |
| 137 | int rx_ring_ref; |
| 138 | |
| 139 | struct timer_list rx_refill_timer; |
| 140 | |
| 141 | struct sk_buff *rx_skbs[NET_RX_RING_SIZE]; |
| 142 | grant_ref_t gref_rx_head; |
| 143 | grant_ref_t grant_rx_ref[NET_RX_RING_SIZE]; |
| 144 | }; |
| 145 | |
| 146 | struct netfront_info { |
| 147 | struct list_head list; |
| 148 | struct net_device *netdev; |
| 149 | |
| 150 | struct xenbus_device *xbdev; |
| 151 | |
| 152 | /* Multi-queue support */ |
| 153 | struct netfront_queue *queues; |
| 154 | |
| 155 | /* Statistics */ |
| 156 | struct netfront_stats __percpu *rx_stats; |
| 157 | struct netfront_stats __percpu *tx_stats; |
| 158 | |
| 159 | atomic_t rx_gso_checksum_fixup; |
| 160 | }; |
| 161 | |
| 162 | struct netfront_rx_info { |
| 163 | struct xen_netif_rx_response rx; |
| 164 | struct xen_netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX - 1]; |
| 165 | }; |
| 166 | |
| 167 | static void skb_entry_set_link(union skb_entry *list, unsigned short id) |
| 168 | { |
| 169 | list->link = id; |
| 170 | } |
| 171 | |
| 172 | static int skb_entry_is_link(const union skb_entry *list) |
| 173 | { |
| 174 | BUILD_BUG_ON(sizeof(list->skb) != sizeof(list->link)); |
| 175 | return (unsigned long)list->skb < PAGE_OFFSET; |
| 176 | } |
| 177 | |
| 178 | /* |
| 179 | * Access macros for acquiring freeing slots in tx_skbs[]. |
| 180 | */ |
| 181 | |
| 182 | static void add_id_to_freelist(unsigned *head, union skb_entry *list, |
| 183 | unsigned short id) |
| 184 | { |
| 185 | skb_entry_set_link(&list[id], *head); |
| 186 | *head = id; |
| 187 | } |
| 188 | |
| 189 | static unsigned short get_id_from_freelist(unsigned *head, |
| 190 | union skb_entry *list) |
| 191 | { |
| 192 | unsigned int id = *head; |
| 193 | *head = list[id].link; |
| 194 | return id; |
| 195 | } |
| 196 | |
| 197 | static int xennet_rxidx(RING_IDX idx) |
| 198 | { |
| 199 | return idx & (NET_RX_RING_SIZE - 1); |
| 200 | } |
| 201 | |
| 202 | static struct sk_buff *xennet_get_rx_skb(struct netfront_queue *queue, |
| 203 | RING_IDX ri) |
| 204 | { |
| 205 | int i = xennet_rxidx(ri); |
| 206 | struct sk_buff *skb = queue->rx_skbs[i]; |
| 207 | queue->rx_skbs[i] = NULL; |
| 208 | return skb; |
| 209 | } |
| 210 | |
| 211 | static grant_ref_t xennet_get_rx_ref(struct netfront_queue *queue, |
| 212 | RING_IDX ri) |
| 213 | { |
| 214 | int i = xennet_rxidx(ri); |
| 215 | grant_ref_t ref = queue->grant_rx_ref[i]; |
| 216 | queue->grant_rx_ref[i] = GRANT_INVALID_REF; |
| 217 | return ref; |
| 218 | } |
| 219 | |
| 220 | #ifdef CONFIG_SYSFS |
| 221 | static const struct attribute_group xennet_dev_group; |
| 222 | #endif |
| 223 | |
| 224 | static bool xennet_can_sg(struct net_device *dev) |
| 225 | { |
| 226 | return dev->features & NETIF_F_SG; |
| 227 | } |
| 228 | |
| 229 | |
| 230 | static void rx_refill_timeout(unsigned long data) |
| 231 | { |
| 232 | struct netfront_queue *queue = (struct netfront_queue *)data; |
| 233 | napi_schedule(&queue->napi); |
| 234 | } |
| 235 | |
| 236 | static int netfront_tx_slot_available(struct netfront_queue *queue) |
| 237 | { |
| 238 | return (queue->tx.req_prod_pvt - queue->tx.rsp_cons) < |
| 239 | (NET_TX_RING_SIZE - MAX_SKB_FRAGS - 2); |
| 240 | } |
| 241 | |
| 242 | static void xennet_maybe_wake_tx(struct netfront_queue *queue) |
| 243 | { |
| 244 | struct net_device *dev = queue->info->netdev; |
| 245 | struct netdev_queue *dev_queue = netdev_get_tx_queue(dev, queue->id); |
| 246 | |
| 247 | if (unlikely(netif_tx_queue_stopped(dev_queue)) && |
| 248 | netfront_tx_slot_available(queue) && |
| 249 | likely(netif_running(dev))) |
| 250 | netif_tx_wake_queue(netdev_get_tx_queue(dev, queue->id)); |
| 251 | } |
| 252 | |
| 253 | |
| 254 | static struct sk_buff *xennet_alloc_one_rx_buffer(struct netfront_queue *queue) |
| 255 | { |
| 256 | struct sk_buff *skb; |
| 257 | struct page *page; |
| 258 | |
| 259 | skb = __netdev_alloc_skb(queue->info->netdev, |
| 260 | RX_COPY_THRESHOLD + NET_IP_ALIGN, |
| 261 | GFP_ATOMIC | __GFP_NOWARN); |
| 262 | if (unlikely(!skb)) |
| 263 | return NULL; |
| 264 | |
| 265 | page = alloc_page(GFP_ATOMIC | __GFP_NOWARN); |
| 266 | if (!page) { |
| 267 | kfree_skb(skb); |
| 268 | return NULL; |
| 269 | } |
| 270 | skb_add_rx_frag(skb, 0, page, 0, 0, PAGE_SIZE); |
| 271 | |
| 272 | /* Align ip header to a 16 bytes boundary */ |
| 273 | skb_reserve(skb, NET_IP_ALIGN); |
| 274 | skb->dev = queue->info->netdev; |
| 275 | |
| 276 | return skb; |
| 277 | } |
| 278 | |
| 279 | |
| 280 | static void xennet_alloc_rx_buffers(struct netfront_queue *queue) |
| 281 | { |
| 282 | RING_IDX req_prod = queue->rx.req_prod_pvt; |
| 283 | int notify; |
| 284 | |
| 285 | if (unlikely(!netif_carrier_ok(queue->info->netdev))) |
| 286 | return; |
| 287 | |
| 288 | for (req_prod = queue->rx.req_prod_pvt; |
| 289 | req_prod - queue->rx.rsp_cons < NET_RX_RING_SIZE; |
| 290 | req_prod++) { |
| 291 | struct sk_buff *skb; |
| 292 | unsigned short id; |
| 293 | grant_ref_t ref; |
| 294 | struct page *page; |
| 295 | struct xen_netif_rx_request *req; |
| 296 | |
| 297 | skb = xennet_alloc_one_rx_buffer(queue); |
| 298 | if (!skb) |
| 299 | break; |
| 300 | |
| 301 | id = xennet_rxidx(req_prod); |
| 302 | |
| 303 | BUG_ON(queue->rx_skbs[id]); |
| 304 | queue->rx_skbs[id] = skb; |
| 305 | |
| 306 | ref = gnttab_claim_grant_reference(&queue->gref_rx_head); |
| 307 | BUG_ON((signed short)ref < 0); |
| 308 | queue->grant_rx_ref[id] = ref; |
| 309 | |
| 310 | page = skb_frag_page(&skb_shinfo(skb)->frags[0]); |
| 311 | |
| 312 | req = RING_GET_REQUEST(&queue->rx, req_prod); |
| 313 | gnttab_page_grant_foreign_access_ref_one(ref, |
| 314 | queue->info->xbdev->otherend_id, |
| 315 | page, |
| 316 | 0); |
| 317 | req->id = id; |
| 318 | req->gref = ref; |
| 319 | } |
| 320 | |
| 321 | queue->rx.req_prod_pvt = req_prod; |
| 322 | |
| 323 | /* Not enough requests? Try again later. */ |
| 324 | if (req_prod - queue->rx.rsp_cons < NET_RX_SLOTS_MIN) { |
| 325 | mod_timer(&queue->rx_refill_timer, jiffies + (HZ/10)); |
| 326 | return; |
| 327 | } |
| 328 | |
| 329 | wmb(); /* barrier so backend seens requests */ |
| 330 | |
| 331 | RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&queue->rx, notify); |
| 332 | if (notify) |
| 333 | notify_remote_via_irq(queue->rx_irq); |
| 334 | } |
| 335 | |
| 336 | static int xennet_open(struct net_device *dev) |
| 337 | { |
| 338 | struct netfront_info *np = netdev_priv(dev); |
| 339 | unsigned int num_queues = dev->real_num_tx_queues; |
| 340 | unsigned int i = 0; |
| 341 | struct netfront_queue *queue = NULL; |
| 342 | |
| 343 | for (i = 0; i < num_queues; ++i) { |
| 344 | queue = &np->queues[i]; |
| 345 | napi_enable(&queue->napi); |
| 346 | |
| 347 | spin_lock_bh(&queue->rx_lock); |
| 348 | if (netif_carrier_ok(dev)) { |
| 349 | xennet_alloc_rx_buffers(queue); |
| 350 | queue->rx.sring->rsp_event = queue->rx.rsp_cons + 1; |
| 351 | if (RING_HAS_UNCONSUMED_RESPONSES(&queue->rx)) |
| 352 | napi_schedule(&queue->napi); |
| 353 | } |
| 354 | spin_unlock_bh(&queue->rx_lock); |
| 355 | } |
| 356 | |
| 357 | netif_tx_start_all_queues(dev); |
| 358 | |
| 359 | return 0; |
| 360 | } |
| 361 | |
| 362 | static void xennet_tx_buf_gc(struct netfront_queue *queue) |
| 363 | { |
| 364 | RING_IDX cons, prod; |
| 365 | unsigned short id; |
| 366 | struct sk_buff *skb; |
| 367 | bool more_to_do; |
| 368 | |
| 369 | BUG_ON(!netif_carrier_ok(queue->info->netdev)); |
| 370 | |
| 371 | do { |
| 372 | prod = queue->tx.sring->rsp_prod; |
| 373 | rmb(); /* Ensure we see responses up to 'rp'. */ |
| 374 | |
| 375 | for (cons = queue->tx.rsp_cons; cons != prod; cons++) { |
| 376 | struct xen_netif_tx_response *txrsp; |
| 377 | |
| 378 | txrsp = RING_GET_RESPONSE(&queue->tx, cons); |
| 379 | if (txrsp->status == XEN_NETIF_RSP_NULL) |
| 380 | continue; |
| 381 | |
| 382 | id = txrsp->id; |
| 383 | skb = queue->tx_skbs[id].skb; |
| 384 | if (unlikely(gnttab_query_foreign_access( |
| 385 | queue->grant_tx_ref[id]) != 0)) { |
| 386 | pr_alert("%s: warning -- grant still in use by backend domain\n", |
| 387 | __func__); |
| 388 | BUG(); |
| 389 | } |
| 390 | gnttab_end_foreign_access_ref( |
| 391 | queue->grant_tx_ref[id], GNTMAP_readonly); |
| 392 | gnttab_release_grant_reference( |
| 393 | &queue->gref_tx_head, queue->grant_tx_ref[id]); |
| 394 | queue->grant_tx_ref[id] = GRANT_INVALID_REF; |
| 395 | queue->grant_tx_page[id] = NULL; |
| 396 | add_id_to_freelist(&queue->tx_skb_freelist, queue->tx_skbs, id); |
| 397 | dev_kfree_skb_irq(skb); |
| 398 | } |
| 399 | |
| 400 | queue->tx.rsp_cons = prod; |
| 401 | |
| 402 | RING_FINAL_CHECK_FOR_RESPONSES(&queue->tx, more_to_do); |
| 403 | } while (more_to_do); |
| 404 | |
| 405 | xennet_maybe_wake_tx(queue); |
| 406 | } |
| 407 | |
| 408 | struct xennet_gnttab_make_txreq { |
| 409 | struct netfront_queue *queue; |
| 410 | struct sk_buff *skb; |
| 411 | struct page *page; |
| 412 | struct xen_netif_tx_request *tx; /* Last request */ |
| 413 | unsigned int size; |
| 414 | }; |
| 415 | |
| 416 | static void xennet_tx_setup_grant(unsigned long gfn, unsigned int offset, |
| 417 | unsigned int len, void *data) |
| 418 | { |
| 419 | struct xennet_gnttab_make_txreq *info = data; |
| 420 | unsigned int id; |
| 421 | struct xen_netif_tx_request *tx; |
| 422 | grant_ref_t ref; |
| 423 | /* convenient aliases */ |
| 424 | struct page *page = info->page; |
| 425 | struct netfront_queue *queue = info->queue; |
| 426 | struct sk_buff *skb = info->skb; |
| 427 | |
| 428 | id = get_id_from_freelist(&queue->tx_skb_freelist, queue->tx_skbs); |
| 429 | tx = RING_GET_REQUEST(&queue->tx, queue->tx.req_prod_pvt++); |
| 430 | ref = gnttab_claim_grant_reference(&queue->gref_tx_head); |
| 431 | BUG_ON((signed short)ref < 0); |
| 432 | |
| 433 | gnttab_grant_foreign_access_ref(ref, queue->info->xbdev->otherend_id, |
| 434 | gfn, GNTMAP_readonly); |
| 435 | |
| 436 | queue->tx_skbs[id].skb = skb; |
| 437 | queue->grant_tx_page[id] = page; |
| 438 | queue->grant_tx_ref[id] = ref; |
| 439 | |
| 440 | tx->id = id; |
| 441 | tx->gref = ref; |
| 442 | tx->offset = offset; |
| 443 | tx->size = len; |
| 444 | tx->flags = 0; |
| 445 | |
| 446 | info->tx = tx; |
| 447 | info->size += tx->size; |
| 448 | } |
| 449 | |
| 450 | static struct xen_netif_tx_request *xennet_make_first_txreq( |
| 451 | struct netfront_queue *queue, struct sk_buff *skb, |
| 452 | struct page *page, unsigned int offset, unsigned int len) |
| 453 | { |
| 454 | struct xennet_gnttab_make_txreq info = { |
| 455 | .queue = queue, |
| 456 | .skb = skb, |
| 457 | .page = page, |
| 458 | .size = 0, |
| 459 | }; |
| 460 | |
| 461 | gnttab_for_one_grant(page, offset, len, xennet_tx_setup_grant, &info); |
| 462 | |
| 463 | return info.tx; |
| 464 | } |
| 465 | |
| 466 | static void xennet_make_one_txreq(unsigned long gfn, unsigned int offset, |
| 467 | unsigned int len, void *data) |
| 468 | { |
| 469 | struct xennet_gnttab_make_txreq *info = data; |
| 470 | |
| 471 | info->tx->flags |= XEN_NETTXF_more_data; |
| 472 | skb_get(info->skb); |
| 473 | xennet_tx_setup_grant(gfn, offset, len, data); |
| 474 | } |
| 475 | |
| 476 | static struct xen_netif_tx_request *xennet_make_txreqs( |
| 477 | struct netfront_queue *queue, struct xen_netif_tx_request *tx, |
| 478 | struct sk_buff *skb, struct page *page, |
| 479 | unsigned int offset, unsigned int len) |
| 480 | { |
| 481 | struct xennet_gnttab_make_txreq info = { |
| 482 | .queue = queue, |
| 483 | .skb = skb, |
| 484 | .tx = tx, |
| 485 | }; |
| 486 | |
| 487 | /* Skip unused frames from start of page */ |
| 488 | page += offset >> PAGE_SHIFT; |
| 489 | offset &= ~PAGE_MASK; |
| 490 | |
| 491 | while (len) { |
| 492 | info.page = page; |
| 493 | info.size = 0; |
| 494 | |
| 495 | gnttab_foreach_grant_in_range(page, offset, len, |
| 496 | xennet_make_one_txreq, |
| 497 | &info); |
| 498 | |
| 499 | page++; |
| 500 | offset = 0; |
| 501 | len -= info.size; |
| 502 | } |
| 503 | |
| 504 | return info.tx; |
| 505 | } |
| 506 | |
| 507 | /* |
| 508 | * Count how many ring slots are required to send this skb. Each frag |
| 509 | * might be a compound page. |
| 510 | */ |
| 511 | static int xennet_count_skb_slots(struct sk_buff *skb) |
| 512 | { |
| 513 | int i, frags = skb_shinfo(skb)->nr_frags; |
| 514 | int slots; |
| 515 | |
| 516 | slots = gnttab_count_grant(offset_in_page(skb->data), |
| 517 | skb_headlen(skb)); |
| 518 | |
| 519 | for (i = 0; i < frags; i++) { |
| 520 | skb_frag_t *frag = skb_shinfo(skb)->frags + i; |
| 521 | unsigned long size = skb_frag_size(frag); |
| 522 | unsigned long offset = frag->page_offset; |
| 523 | |
| 524 | /* Skip unused frames from start of page */ |
| 525 | offset &= ~PAGE_MASK; |
| 526 | |
| 527 | slots += gnttab_count_grant(offset, size); |
| 528 | } |
| 529 | |
| 530 | return slots; |
| 531 | } |
| 532 | |
| 533 | static u16 xennet_select_queue(struct net_device *dev, struct sk_buff *skb, |
| 534 | void *accel_priv, select_queue_fallback_t fallback) |
| 535 | { |
| 536 | unsigned int num_queues = dev->real_num_tx_queues; |
| 537 | u32 hash; |
| 538 | u16 queue_idx; |
| 539 | |
| 540 | /* First, check if there is only one queue */ |
| 541 | if (num_queues == 1) { |
| 542 | queue_idx = 0; |
| 543 | } else { |
| 544 | hash = skb_get_hash(skb); |
| 545 | queue_idx = hash % num_queues; |
| 546 | } |
| 547 | |
| 548 | return queue_idx; |
| 549 | } |
| 550 | |
| 551 | #define MAX_XEN_SKB_FRAGS (65536 / XEN_PAGE_SIZE + 1) |
| 552 | |
| 553 | static int xennet_start_xmit(struct sk_buff *skb, struct net_device *dev) |
| 554 | { |
| 555 | struct netfront_info *np = netdev_priv(dev); |
| 556 | struct netfront_stats *tx_stats = this_cpu_ptr(np->tx_stats); |
| 557 | struct xen_netif_tx_request *tx, *first_tx; |
| 558 | unsigned int i; |
| 559 | int notify; |
| 560 | int slots; |
| 561 | struct page *page; |
| 562 | unsigned int offset; |
| 563 | unsigned int len; |
| 564 | unsigned long flags; |
| 565 | struct netfront_queue *queue = NULL; |
| 566 | unsigned int num_queues = dev->real_num_tx_queues; |
| 567 | u16 queue_index; |
| 568 | |
| 569 | /* Drop the packet if no queues are set up */ |
| 570 | if (num_queues < 1) |
| 571 | goto drop; |
| 572 | /* Determine which queue to transmit this SKB on */ |
| 573 | queue_index = skb_get_queue_mapping(skb); |
| 574 | queue = &np->queues[queue_index]; |
| 575 | |
| 576 | /* If skb->len is too big for wire format, drop skb and alert |
| 577 | * user about misconfiguration. |
| 578 | */ |
| 579 | if (unlikely(skb->len > XEN_NETIF_MAX_TX_SIZE)) { |
| 580 | net_alert_ratelimited( |
| 581 | "xennet: skb->len = %u, too big for wire format\n", |
| 582 | skb->len); |
| 583 | goto drop; |
| 584 | } |
| 585 | |
| 586 | slots = xennet_count_skb_slots(skb); |
| 587 | if (unlikely(slots > MAX_XEN_SKB_FRAGS + 1)) { |
| 588 | net_dbg_ratelimited("xennet: skb rides the rocket: %d slots, %d bytes\n", |
| 589 | slots, skb->len); |
| 590 | if (skb_linearize(skb)) |
| 591 | goto drop; |
| 592 | } |
| 593 | |
| 594 | page = virt_to_page(skb->data); |
| 595 | offset = offset_in_page(skb->data); |
| 596 | len = skb_headlen(skb); |
| 597 | |
| 598 | spin_lock_irqsave(&queue->tx_lock, flags); |
| 599 | |
| 600 | if (unlikely(!netif_carrier_ok(dev) || |
| 601 | (slots > 1 && !xennet_can_sg(dev)) || |
| 602 | netif_needs_gso(skb, netif_skb_features(skb)))) { |
| 603 | spin_unlock_irqrestore(&queue->tx_lock, flags); |
| 604 | goto drop; |
| 605 | } |
| 606 | |
| 607 | /* First request for the linear area. */ |
| 608 | first_tx = tx = xennet_make_first_txreq(queue, skb, |
| 609 | page, offset, len); |
| 610 | offset += tx->size; |
| 611 | if (offset == PAGE_SIZE) { |
| 612 | page++; |
| 613 | offset = 0; |
| 614 | } |
| 615 | len -= tx->size; |
| 616 | |
| 617 | if (skb->ip_summed == CHECKSUM_PARTIAL) |
| 618 | /* local packet? */ |
| 619 | tx->flags |= XEN_NETTXF_csum_blank | XEN_NETTXF_data_validated; |
| 620 | else if (skb->ip_summed == CHECKSUM_UNNECESSARY) |
| 621 | /* remote but checksummed. */ |
| 622 | tx->flags |= XEN_NETTXF_data_validated; |
| 623 | |
| 624 | /* Optional extra info after the first request. */ |
| 625 | if (skb_shinfo(skb)->gso_size) { |
| 626 | struct xen_netif_extra_info *gso; |
| 627 | |
| 628 | gso = (struct xen_netif_extra_info *) |
| 629 | RING_GET_REQUEST(&queue->tx, queue->tx.req_prod_pvt++); |
| 630 | |
| 631 | tx->flags |= XEN_NETTXF_extra_info; |
| 632 | |
| 633 | gso->u.gso.size = skb_shinfo(skb)->gso_size; |
| 634 | gso->u.gso.type = (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6) ? |
| 635 | XEN_NETIF_GSO_TYPE_TCPV6 : |
| 636 | XEN_NETIF_GSO_TYPE_TCPV4; |
| 637 | gso->u.gso.pad = 0; |
| 638 | gso->u.gso.features = 0; |
| 639 | |
| 640 | gso->type = XEN_NETIF_EXTRA_TYPE_GSO; |
| 641 | gso->flags = 0; |
| 642 | } |
| 643 | |
| 644 | /* Requests for the rest of the linear area. */ |
| 645 | tx = xennet_make_txreqs(queue, tx, skb, page, offset, len); |
| 646 | |
| 647 | /* Requests for all the frags. */ |
| 648 | for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { |
| 649 | skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; |
| 650 | tx = xennet_make_txreqs(queue, tx, skb, |
| 651 | skb_frag_page(frag), frag->page_offset, |
| 652 | skb_frag_size(frag)); |
| 653 | } |
| 654 | |
| 655 | /* First request has the packet length. */ |
| 656 | first_tx->size = skb->len; |
| 657 | |
| 658 | RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&queue->tx, notify); |
| 659 | if (notify) |
| 660 | notify_remote_via_irq(queue->tx_irq); |
| 661 | |
| 662 | u64_stats_update_begin(&tx_stats->syncp); |
| 663 | tx_stats->bytes += skb->len; |
| 664 | tx_stats->packets++; |
| 665 | u64_stats_update_end(&tx_stats->syncp); |
| 666 | |
| 667 | /* Note: It is not safe to access skb after xennet_tx_buf_gc()! */ |
| 668 | xennet_tx_buf_gc(queue); |
| 669 | |
| 670 | if (!netfront_tx_slot_available(queue)) |
| 671 | netif_tx_stop_queue(netdev_get_tx_queue(dev, queue->id)); |
| 672 | |
| 673 | spin_unlock_irqrestore(&queue->tx_lock, flags); |
| 674 | |
| 675 | return NETDEV_TX_OK; |
| 676 | |
| 677 | drop: |
| 678 | dev->stats.tx_dropped++; |
| 679 | dev_kfree_skb_any(skb); |
| 680 | return NETDEV_TX_OK; |
| 681 | } |
| 682 | |
| 683 | static int xennet_close(struct net_device *dev) |
| 684 | { |
| 685 | struct netfront_info *np = netdev_priv(dev); |
| 686 | unsigned int num_queues = dev->real_num_tx_queues; |
| 687 | unsigned int i; |
| 688 | struct netfront_queue *queue; |
| 689 | netif_tx_stop_all_queues(np->netdev); |
| 690 | for (i = 0; i < num_queues; ++i) { |
| 691 | queue = &np->queues[i]; |
| 692 | napi_disable(&queue->napi); |
| 693 | } |
| 694 | return 0; |
| 695 | } |
| 696 | |
| 697 | static void xennet_move_rx_slot(struct netfront_queue *queue, struct sk_buff *skb, |
| 698 | grant_ref_t ref) |
| 699 | { |
| 700 | int new = xennet_rxidx(queue->rx.req_prod_pvt); |
| 701 | |
| 702 | BUG_ON(queue->rx_skbs[new]); |
| 703 | queue->rx_skbs[new] = skb; |
| 704 | queue->grant_rx_ref[new] = ref; |
| 705 | RING_GET_REQUEST(&queue->rx, queue->rx.req_prod_pvt)->id = new; |
| 706 | RING_GET_REQUEST(&queue->rx, queue->rx.req_prod_pvt)->gref = ref; |
| 707 | queue->rx.req_prod_pvt++; |
| 708 | } |
| 709 | |
| 710 | static int xennet_get_extras(struct netfront_queue *queue, |
| 711 | struct xen_netif_extra_info *extras, |
| 712 | RING_IDX rp) |
| 713 | |
| 714 | { |
| 715 | struct xen_netif_extra_info *extra; |
| 716 | struct device *dev = &queue->info->netdev->dev; |
| 717 | RING_IDX cons = queue->rx.rsp_cons; |
| 718 | int err = 0; |
| 719 | |
| 720 | do { |
| 721 | struct sk_buff *skb; |
| 722 | grant_ref_t ref; |
| 723 | |
| 724 | if (unlikely(cons + 1 == rp)) { |
| 725 | if (net_ratelimit()) |
| 726 | dev_warn(dev, "Missing extra info\n"); |
| 727 | err = -EBADR; |
| 728 | break; |
| 729 | } |
| 730 | |
| 731 | extra = (struct xen_netif_extra_info *) |
| 732 | RING_GET_RESPONSE(&queue->rx, ++cons); |
| 733 | |
| 734 | if (unlikely(!extra->type || |
| 735 | extra->type >= XEN_NETIF_EXTRA_TYPE_MAX)) { |
| 736 | if (net_ratelimit()) |
| 737 | dev_warn(dev, "Invalid extra type: %d\n", |
| 738 | extra->type); |
| 739 | err = -EINVAL; |
| 740 | } else { |
| 741 | memcpy(&extras[extra->type - 1], extra, |
| 742 | sizeof(*extra)); |
| 743 | } |
| 744 | |
| 745 | skb = xennet_get_rx_skb(queue, cons); |
| 746 | ref = xennet_get_rx_ref(queue, cons); |
| 747 | xennet_move_rx_slot(queue, skb, ref); |
| 748 | } while (extra->flags & XEN_NETIF_EXTRA_FLAG_MORE); |
| 749 | |
| 750 | queue->rx.rsp_cons = cons; |
| 751 | return err; |
| 752 | } |
| 753 | |
| 754 | static int xennet_get_responses(struct netfront_queue *queue, |
| 755 | struct netfront_rx_info *rinfo, RING_IDX rp, |
| 756 | struct sk_buff_head *list) |
| 757 | { |
| 758 | struct xen_netif_rx_response *rx = &rinfo->rx; |
| 759 | struct xen_netif_extra_info *extras = rinfo->extras; |
| 760 | struct device *dev = &queue->info->netdev->dev; |
| 761 | RING_IDX cons = queue->rx.rsp_cons; |
| 762 | struct sk_buff *skb = xennet_get_rx_skb(queue, cons); |
| 763 | grant_ref_t ref = xennet_get_rx_ref(queue, cons); |
| 764 | int max = MAX_SKB_FRAGS + (rx->status <= RX_COPY_THRESHOLD); |
| 765 | int slots = 1; |
| 766 | int err = 0; |
| 767 | unsigned long ret; |
| 768 | |
| 769 | if (rx->flags & XEN_NETRXF_extra_info) { |
| 770 | err = xennet_get_extras(queue, extras, rp); |
| 771 | cons = queue->rx.rsp_cons; |
| 772 | } |
| 773 | |
| 774 | for (;;) { |
| 775 | if (unlikely(rx->status < 0 || |
| 776 | rx->offset + rx->status > XEN_PAGE_SIZE)) { |
| 777 | if (net_ratelimit()) |
| 778 | dev_warn(dev, "rx->offset: %u, size: %d\n", |
| 779 | rx->offset, rx->status); |
| 780 | xennet_move_rx_slot(queue, skb, ref); |
| 781 | err = -EINVAL; |
| 782 | goto next; |
| 783 | } |
| 784 | |
| 785 | /* |
| 786 | * This definitely indicates a bug, either in this driver or in |
| 787 | * the backend driver. In future this should flag the bad |
| 788 | * situation to the system controller to reboot the backend. |
| 789 | */ |
| 790 | if (ref == GRANT_INVALID_REF) { |
| 791 | if (net_ratelimit()) |
| 792 | dev_warn(dev, "Bad rx response id %d.\n", |
| 793 | rx->id); |
| 794 | err = -EINVAL; |
| 795 | goto next; |
| 796 | } |
| 797 | |
| 798 | ret = gnttab_end_foreign_access_ref(ref, 0); |
| 799 | BUG_ON(!ret); |
| 800 | |
| 801 | gnttab_release_grant_reference(&queue->gref_rx_head, ref); |
| 802 | |
| 803 | __skb_queue_tail(list, skb); |
| 804 | |
| 805 | next: |
| 806 | if (!(rx->flags & XEN_NETRXF_more_data)) |
| 807 | break; |
| 808 | |
| 809 | if (cons + slots == rp) { |
| 810 | if (net_ratelimit()) |
| 811 | dev_warn(dev, "Need more slots\n"); |
| 812 | err = -ENOENT; |
| 813 | break; |
| 814 | } |
| 815 | |
| 816 | rx = RING_GET_RESPONSE(&queue->rx, cons + slots); |
| 817 | skb = xennet_get_rx_skb(queue, cons + slots); |
| 818 | ref = xennet_get_rx_ref(queue, cons + slots); |
| 819 | slots++; |
| 820 | } |
| 821 | |
| 822 | if (unlikely(slots > max)) { |
| 823 | if (net_ratelimit()) |
| 824 | dev_warn(dev, "Too many slots\n"); |
| 825 | err = -E2BIG; |
| 826 | } |
| 827 | |
| 828 | if (unlikely(err)) |
| 829 | queue->rx.rsp_cons = cons + slots; |
| 830 | |
| 831 | return err; |
| 832 | } |
| 833 | |
| 834 | static int xennet_set_skb_gso(struct sk_buff *skb, |
| 835 | struct xen_netif_extra_info *gso) |
| 836 | { |
| 837 | if (!gso->u.gso.size) { |
| 838 | if (net_ratelimit()) |
| 839 | pr_warn("GSO size must not be zero\n"); |
| 840 | return -EINVAL; |
| 841 | } |
| 842 | |
| 843 | if (gso->u.gso.type != XEN_NETIF_GSO_TYPE_TCPV4 && |
| 844 | gso->u.gso.type != XEN_NETIF_GSO_TYPE_TCPV6) { |
| 845 | if (net_ratelimit()) |
| 846 | pr_warn("Bad GSO type %d\n", gso->u.gso.type); |
| 847 | return -EINVAL; |
| 848 | } |
| 849 | |
| 850 | skb_shinfo(skb)->gso_size = gso->u.gso.size; |
| 851 | skb_shinfo(skb)->gso_type = |
| 852 | (gso->u.gso.type == XEN_NETIF_GSO_TYPE_TCPV4) ? |
| 853 | SKB_GSO_TCPV4 : |
| 854 | SKB_GSO_TCPV6; |
| 855 | |
| 856 | /* Header must be checked, and gso_segs computed. */ |
| 857 | skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; |
| 858 | skb_shinfo(skb)->gso_segs = 0; |
| 859 | |
| 860 | return 0; |
| 861 | } |
| 862 | |
| 863 | static RING_IDX xennet_fill_frags(struct netfront_queue *queue, |
| 864 | struct sk_buff *skb, |
| 865 | struct sk_buff_head *list) |
| 866 | { |
| 867 | struct skb_shared_info *shinfo = skb_shinfo(skb); |
| 868 | RING_IDX cons = queue->rx.rsp_cons; |
| 869 | struct sk_buff *nskb; |
| 870 | |
| 871 | while ((nskb = __skb_dequeue(list))) { |
| 872 | struct xen_netif_rx_response *rx = |
| 873 | RING_GET_RESPONSE(&queue->rx, ++cons); |
| 874 | skb_frag_t *nfrag = &skb_shinfo(nskb)->frags[0]; |
| 875 | |
| 876 | if (shinfo->nr_frags == MAX_SKB_FRAGS) { |
| 877 | unsigned int pull_to = NETFRONT_SKB_CB(skb)->pull_to; |
| 878 | |
| 879 | BUG_ON(pull_to <= skb_headlen(skb)); |
| 880 | __pskb_pull_tail(skb, pull_to - skb_headlen(skb)); |
| 881 | } |
| 882 | BUG_ON(shinfo->nr_frags >= MAX_SKB_FRAGS); |
| 883 | |
| 884 | skb_add_rx_frag(skb, shinfo->nr_frags, skb_frag_page(nfrag), |
| 885 | rx->offset, rx->status, PAGE_SIZE); |
| 886 | |
| 887 | skb_shinfo(nskb)->nr_frags = 0; |
| 888 | kfree_skb(nskb); |
| 889 | } |
| 890 | |
| 891 | return cons; |
| 892 | } |
| 893 | |
| 894 | static int checksum_setup(struct net_device *dev, struct sk_buff *skb) |
| 895 | { |
| 896 | bool recalculate_partial_csum = false; |
| 897 | |
| 898 | /* |
| 899 | * A GSO SKB must be CHECKSUM_PARTIAL. However some buggy |
| 900 | * peers can fail to set NETRXF_csum_blank when sending a GSO |
| 901 | * frame. In this case force the SKB to CHECKSUM_PARTIAL and |
| 902 | * recalculate the partial checksum. |
| 903 | */ |
| 904 | if (skb->ip_summed != CHECKSUM_PARTIAL && skb_is_gso(skb)) { |
| 905 | struct netfront_info *np = netdev_priv(dev); |
| 906 | atomic_inc(&np->rx_gso_checksum_fixup); |
| 907 | skb->ip_summed = CHECKSUM_PARTIAL; |
| 908 | recalculate_partial_csum = true; |
| 909 | } |
| 910 | |
| 911 | /* A non-CHECKSUM_PARTIAL SKB does not require setup. */ |
| 912 | if (skb->ip_summed != CHECKSUM_PARTIAL) |
| 913 | return 0; |
| 914 | |
| 915 | return skb_checksum_setup(skb, recalculate_partial_csum); |
| 916 | } |
| 917 | |
| 918 | static int handle_incoming_queue(struct netfront_queue *queue, |
| 919 | struct sk_buff_head *rxq) |
| 920 | { |
| 921 | struct netfront_stats *rx_stats = this_cpu_ptr(queue->info->rx_stats); |
| 922 | int packets_dropped = 0; |
| 923 | struct sk_buff *skb; |
| 924 | |
| 925 | while ((skb = __skb_dequeue(rxq)) != NULL) { |
| 926 | int pull_to = NETFRONT_SKB_CB(skb)->pull_to; |
| 927 | |
| 928 | if (pull_to > skb_headlen(skb)) |
| 929 | __pskb_pull_tail(skb, pull_to - skb_headlen(skb)); |
| 930 | |
| 931 | /* Ethernet work: Delayed to here as it peeks the header. */ |
| 932 | skb->protocol = eth_type_trans(skb, queue->info->netdev); |
| 933 | skb_reset_network_header(skb); |
| 934 | |
| 935 | if (checksum_setup(queue->info->netdev, skb)) { |
| 936 | kfree_skb(skb); |
| 937 | packets_dropped++; |
| 938 | queue->info->netdev->stats.rx_errors++; |
| 939 | continue; |
| 940 | } |
| 941 | |
| 942 | u64_stats_update_begin(&rx_stats->syncp); |
| 943 | rx_stats->packets++; |
| 944 | rx_stats->bytes += skb->len; |
| 945 | u64_stats_update_end(&rx_stats->syncp); |
| 946 | |
| 947 | /* Pass it up. */ |
| 948 | napi_gro_receive(&queue->napi, skb); |
| 949 | } |
| 950 | |
| 951 | return packets_dropped; |
| 952 | } |
| 953 | |
| 954 | static int xennet_poll(struct napi_struct *napi, int budget) |
| 955 | { |
| 956 | struct netfront_queue *queue = container_of(napi, struct netfront_queue, napi); |
| 957 | struct net_device *dev = queue->info->netdev; |
| 958 | struct sk_buff *skb; |
| 959 | struct netfront_rx_info rinfo; |
| 960 | struct xen_netif_rx_response *rx = &rinfo.rx; |
| 961 | struct xen_netif_extra_info *extras = rinfo.extras; |
| 962 | RING_IDX i, rp; |
| 963 | int work_done; |
| 964 | struct sk_buff_head rxq; |
| 965 | struct sk_buff_head errq; |
| 966 | struct sk_buff_head tmpq; |
| 967 | int err; |
| 968 | |
| 969 | spin_lock(&queue->rx_lock); |
| 970 | |
| 971 | skb_queue_head_init(&rxq); |
| 972 | skb_queue_head_init(&errq); |
| 973 | skb_queue_head_init(&tmpq); |
| 974 | |
| 975 | rp = queue->rx.sring->rsp_prod; |
| 976 | rmb(); /* Ensure we see queued responses up to 'rp'. */ |
| 977 | |
| 978 | i = queue->rx.rsp_cons; |
| 979 | work_done = 0; |
| 980 | while ((i != rp) && (work_done < budget)) { |
| 981 | memcpy(rx, RING_GET_RESPONSE(&queue->rx, i), sizeof(*rx)); |
| 982 | memset(extras, 0, sizeof(rinfo.extras)); |
| 983 | |
| 984 | err = xennet_get_responses(queue, &rinfo, rp, &tmpq); |
| 985 | |
| 986 | if (unlikely(err)) { |
| 987 | err: |
| 988 | while ((skb = __skb_dequeue(&tmpq))) |
| 989 | __skb_queue_tail(&errq, skb); |
| 990 | dev->stats.rx_errors++; |
| 991 | i = queue->rx.rsp_cons; |
| 992 | continue; |
| 993 | } |
| 994 | |
| 995 | skb = __skb_dequeue(&tmpq); |
| 996 | |
| 997 | if (extras[XEN_NETIF_EXTRA_TYPE_GSO - 1].type) { |
| 998 | struct xen_netif_extra_info *gso; |
| 999 | gso = &extras[XEN_NETIF_EXTRA_TYPE_GSO - 1]; |
| 1000 | |
| 1001 | if (unlikely(xennet_set_skb_gso(skb, gso))) { |
| 1002 | __skb_queue_head(&tmpq, skb); |
| 1003 | queue->rx.rsp_cons += skb_queue_len(&tmpq); |
| 1004 | goto err; |
| 1005 | } |
| 1006 | } |
| 1007 | |
| 1008 | NETFRONT_SKB_CB(skb)->pull_to = rx->status; |
| 1009 | if (NETFRONT_SKB_CB(skb)->pull_to > RX_COPY_THRESHOLD) |
| 1010 | NETFRONT_SKB_CB(skb)->pull_to = RX_COPY_THRESHOLD; |
| 1011 | |
| 1012 | skb_shinfo(skb)->frags[0].page_offset = rx->offset; |
| 1013 | skb_frag_size_set(&skb_shinfo(skb)->frags[0], rx->status); |
| 1014 | skb->data_len = rx->status; |
| 1015 | skb->len += rx->status; |
| 1016 | |
| 1017 | i = xennet_fill_frags(queue, skb, &tmpq); |
| 1018 | |
| 1019 | if (rx->flags & XEN_NETRXF_csum_blank) |
| 1020 | skb->ip_summed = CHECKSUM_PARTIAL; |
| 1021 | else if (rx->flags & XEN_NETRXF_data_validated) |
| 1022 | skb->ip_summed = CHECKSUM_UNNECESSARY; |
| 1023 | |
| 1024 | __skb_queue_tail(&rxq, skb); |
| 1025 | |
| 1026 | queue->rx.rsp_cons = ++i; |
| 1027 | work_done++; |
| 1028 | } |
| 1029 | |
| 1030 | __skb_queue_purge(&errq); |
| 1031 | |
| 1032 | work_done -= handle_incoming_queue(queue, &rxq); |
| 1033 | |
| 1034 | xennet_alloc_rx_buffers(queue); |
| 1035 | |
| 1036 | if (work_done < budget) { |
| 1037 | int more_to_do = 0; |
| 1038 | |
| 1039 | napi_complete(napi); |
| 1040 | |
| 1041 | RING_FINAL_CHECK_FOR_RESPONSES(&queue->rx, more_to_do); |
| 1042 | if (more_to_do) |
| 1043 | napi_schedule(napi); |
| 1044 | } |
| 1045 | |
| 1046 | spin_unlock(&queue->rx_lock); |
| 1047 | |
| 1048 | return work_done; |
| 1049 | } |
| 1050 | |
| 1051 | static int xennet_change_mtu(struct net_device *dev, int mtu) |
| 1052 | { |
| 1053 | int max = xennet_can_sg(dev) ? XEN_NETIF_MAX_TX_SIZE : ETH_DATA_LEN; |
| 1054 | |
| 1055 | if (mtu > max) |
| 1056 | return -EINVAL; |
| 1057 | dev->mtu = mtu; |
| 1058 | return 0; |
| 1059 | } |
| 1060 | |
| 1061 | static struct rtnl_link_stats64 *xennet_get_stats64(struct net_device *dev, |
| 1062 | struct rtnl_link_stats64 *tot) |
| 1063 | { |
| 1064 | struct netfront_info *np = netdev_priv(dev); |
| 1065 | int cpu; |
| 1066 | |
| 1067 | for_each_possible_cpu(cpu) { |
| 1068 | struct netfront_stats *rx_stats = per_cpu_ptr(np->rx_stats, cpu); |
| 1069 | struct netfront_stats *tx_stats = per_cpu_ptr(np->tx_stats, cpu); |
| 1070 | u64 rx_packets, rx_bytes, tx_packets, tx_bytes; |
| 1071 | unsigned int start; |
| 1072 | |
| 1073 | do { |
| 1074 | start = u64_stats_fetch_begin_irq(&tx_stats->syncp); |
| 1075 | tx_packets = tx_stats->packets; |
| 1076 | tx_bytes = tx_stats->bytes; |
| 1077 | } while (u64_stats_fetch_retry_irq(&tx_stats->syncp, start)); |
| 1078 | |
| 1079 | do { |
| 1080 | start = u64_stats_fetch_begin_irq(&rx_stats->syncp); |
| 1081 | rx_packets = rx_stats->packets; |
| 1082 | rx_bytes = rx_stats->bytes; |
| 1083 | } while (u64_stats_fetch_retry_irq(&rx_stats->syncp, start)); |
| 1084 | |
| 1085 | tot->rx_packets += rx_packets; |
| 1086 | tot->tx_packets += tx_packets; |
| 1087 | tot->rx_bytes += rx_bytes; |
| 1088 | tot->tx_bytes += tx_bytes; |
| 1089 | } |
| 1090 | |
| 1091 | tot->rx_errors = dev->stats.rx_errors; |
| 1092 | tot->tx_dropped = dev->stats.tx_dropped; |
| 1093 | |
| 1094 | return tot; |
| 1095 | } |
| 1096 | |
| 1097 | static void xennet_release_tx_bufs(struct netfront_queue *queue) |
| 1098 | { |
| 1099 | struct sk_buff *skb; |
| 1100 | int i; |
| 1101 | |
| 1102 | for (i = 0; i < NET_TX_RING_SIZE; i++) { |
| 1103 | /* Skip over entries which are actually freelist references */ |
| 1104 | if (skb_entry_is_link(&queue->tx_skbs[i])) |
| 1105 | continue; |
| 1106 | |
| 1107 | skb = queue->tx_skbs[i].skb; |
| 1108 | get_page(queue->grant_tx_page[i]); |
| 1109 | gnttab_end_foreign_access(queue->grant_tx_ref[i], |
| 1110 | GNTMAP_readonly, |
| 1111 | (unsigned long)page_address(queue->grant_tx_page[i])); |
| 1112 | queue->grant_tx_page[i] = NULL; |
| 1113 | queue->grant_tx_ref[i] = GRANT_INVALID_REF; |
| 1114 | add_id_to_freelist(&queue->tx_skb_freelist, queue->tx_skbs, i); |
| 1115 | dev_kfree_skb_irq(skb); |
| 1116 | } |
| 1117 | } |
| 1118 | |
| 1119 | static void xennet_release_rx_bufs(struct netfront_queue *queue) |
| 1120 | { |
| 1121 | int id, ref; |
| 1122 | |
| 1123 | spin_lock_bh(&queue->rx_lock); |
| 1124 | |
| 1125 | for (id = 0; id < NET_RX_RING_SIZE; id++) { |
| 1126 | struct sk_buff *skb; |
| 1127 | struct page *page; |
| 1128 | |
| 1129 | skb = queue->rx_skbs[id]; |
| 1130 | if (!skb) |
| 1131 | continue; |
| 1132 | |
| 1133 | ref = queue->grant_rx_ref[id]; |
| 1134 | if (ref == GRANT_INVALID_REF) |
| 1135 | continue; |
| 1136 | |
| 1137 | page = skb_frag_page(&skb_shinfo(skb)->frags[0]); |
| 1138 | |
| 1139 | /* gnttab_end_foreign_access() needs a page ref until |
| 1140 | * foreign access is ended (which may be deferred). |
| 1141 | */ |
| 1142 | get_page(page); |
| 1143 | gnttab_end_foreign_access(ref, 0, |
| 1144 | (unsigned long)page_address(page)); |
| 1145 | queue->grant_rx_ref[id] = GRANT_INVALID_REF; |
| 1146 | |
| 1147 | kfree_skb(skb); |
| 1148 | } |
| 1149 | |
| 1150 | spin_unlock_bh(&queue->rx_lock); |
| 1151 | } |
| 1152 | |
| 1153 | static netdev_features_t xennet_fix_features(struct net_device *dev, |
| 1154 | netdev_features_t features) |
| 1155 | { |
| 1156 | struct netfront_info *np = netdev_priv(dev); |
| 1157 | int val; |
| 1158 | |
| 1159 | if (features & NETIF_F_SG) { |
| 1160 | if (xenbus_scanf(XBT_NIL, np->xbdev->otherend, "feature-sg", |
| 1161 | "%d", &val) < 0) |
| 1162 | val = 0; |
| 1163 | |
| 1164 | if (!val) |
| 1165 | features &= ~NETIF_F_SG; |
| 1166 | } |
| 1167 | |
| 1168 | if (features & NETIF_F_IPV6_CSUM) { |
| 1169 | if (xenbus_scanf(XBT_NIL, np->xbdev->otherend, |
| 1170 | "feature-ipv6-csum-offload", "%d", &val) < 0) |
| 1171 | val = 0; |
| 1172 | |
| 1173 | if (!val) |
| 1174 | features &= ~NETIF_F_IPV6_CSUM; |
| 1175 | } |
| 1176 | |
| 1177 | if (features & NETIF_F_TSO) { |
| 1178 | if (xenbus_scanf(XBT_NIL, np->xbdev->otherend, |
| 1179 | "feature-gso-tcpv4", "%d", &val) < 0) |
| 1180 | val = 0; |
| 1181 | |
| 1182 | if (!val) |
| 1183 | features &= ~NETIF_F_TSO; |
| 1184 | } |
| 1185 | |
| 1186 | if (features & NETIF_F_TSO6) { |
| 1187 | if (xenbus_scanf(XBT_NIL, np->xbdev->otherend, |
| 1188 | "feature-gso-tcpv6", "%d", &val) < 0) |
| 1189 | val = 0; |
| 1190 | |
| 1191 | if (!val) |
| 1192 | features &= ~NETIF_F_TSO6; |
| 1193 | } |
| 1194 | |
| 1195 | return features; |
| 1196 | } |
| 1197 | |
| 1198 | static int xennet_set_features(struct net_device *dev, |
| 1199 | netdev_features_t features) |
| 1200 | { |
| 1201 | if (!(features & NETIF_F_SG) && dev->mtu > ETH_DATA_LEN) { |
| 1202 | netdev_info(dev, "Reducing MTU because no SG offload"); |
| 1203 | dev->mtu = ETH_DATA_LEN; |
| 1204 | } |
| 1205 | |
| 1206 | return 0; |
| 1207 | } |
| 1208 | |
| 1209 | static irqreturn_t xennet_tx_interrupt(int irq, void *dev_id) |
| 1210 | { |
| 1211 | struct netfront_queue *queue = dev_id; |
| 1212 | unsigned long flags; |
| 1213 | |
| 1214 | spin_lock_irqsave(&queue->tx_lock, flags); |
| 1215 | xennet_tx_buf_gc(queue); |
| 1216 | spin_unlock_irqrestore(&queue->tx_lock, flags); |
| 1217 | |
| 1218 | return IRQ_HANDLED; |
| 1219 | } |
| 1220 | |
| 1221 | static irqreturn_t xennet_rx_interrupt(int irq, void *dev_id) |
| 1222 | { |
| 1223 | struct netfront_queue *queue = dev_id; |
| 1224 | struct net_device *dev = queue->info->netdev; |
| 1225 | |
| 1226 | if (likely(netif_carrier_ok(dev) && |
| 1227 | RING_HAS_UNCONSUMED_RESPONSES(&queue->rx))) |
| 1228 | napi_schedule(&queue->napi); |
| 1229 | |
| 1230 | return IRQ_HANDLED; |
| 1231 | } |
| 1232 | |
| 1233 | static irqreturn_t xennet_interrupt(int irq, void *dev_id) |
| 1234 | { |
| 1235 | xennet_tx_interrupt(irq, dev_id); |
| 1236 | xennet_rx_interrupt(irq, dev_id); |
| 1237 | return IRQ_HANDLED; |
| 1238 | } |
| 1239 | |
| 1240 | #ifdef CONFIG_NET_POLL_CONTROLLER |
| 1241 | static void xennet_poll_controller(struct net_device *dev) |
| 1242 | { |
| 1243 | /* Poll each queue */ |
| 1244 | struct netfront_info *info = netdev_priv(dev); |
| 1245 | unsigned int num_queues = dev->real_num_tx_queues; |
| 1246 | unsigned int i; |
| 1247 | for (i = 0; i < num_queues; ++i) |
| 1248 | xennet_interrupt(0, &info->queues[i]); |
| 1249 | } |
| 1250 | #endif |
| 1251 | |
| 1252 | static const struct net_device_ops xennet_netdev_ops = { |
| 1253 | .ndo_open = xennet_open, |
| 1254 | .ndo_stop = xennet_close, |
| 1255 | .ndo_start_xmit = xennet_start_xmit, |
| 1256 | .ndo_change_mtu = xennet_change_mtu, |
| 1257 | .ndo_get_stats64 = xennet_get_stats64, |
| 1258 | .ndo_set_mac_address = eth_mac_addr, |
| 1259 | .ndo_validate_addr = eth_validate_addr, |
| 1260 | .ndo_fix_features = xennet_fix_features, |
| 1261 | .ndo_set_features = xennet_set_features, |
| 1262 | .ndo_select_queue = xennet_select_queue, |
| 1263 | #ifdef CONFIG_NET_POLL_CONTROLLER |
| 1264 | .ndo_poll_controller = xennet_poll_controller, |
| 1265 | #endif |
| 1266 | }; |
| 1267 | |
| 1268 | static void xennet_free_netdev(struct net_device *netdev) |
| 1269 | { |
| 1270 | struct netfront_info *np = netdev_priv(netdev); |
| 1271 | |
| 1272 | free_percpu(np->rx_stats); |
| 1273 | free_percpu(np->tx_stats); |
| 1274 | free_netdev(netdev); |
| 1275 | } |
| 1276 | |
| 1277 | static struct net_device *xennet_create_dev(struct xenbus_device *dev) |
| 1278 | { |
| 1279 | int err; |
| 1280 | struct net_device *netdev; |
| 1281 | struct netfront_info *np; |
| 1282 | |
| 1283 | netdev = alloc_etherdev_mq(sizeof(struct netfront_info), xennet_max_queues); |
| 1284 | if (!netdev) |
| 1285 | return ERR_PTR(-ENOMEM); |
| 1286 | |
| 1287 | np = netdev_priv(netdev); |
| 1288 | np->xbdev = dev; |
| 1289 | |
| 1290 | np->queues = NULL; |
| 1291 | |
| 1292 | err = -ENOMEM; |
| 1293 | np->rx_stats = netdev_alloc_pcpu_stats(struct netfront_stats); |
| 1294 | if (np->rx_stats == NULL) |
| 1295 | goto exit; |
| 1296 | np->tx_stats = netdev_alloc_pcpu_stats(struct netfront_stats); |
| 1297 | if (np->tx_stats == NULL) |
| 1298 | goto exit; |
| 1299 | |
| 1300 | netdev->netdev_ops = &xennet_netdev_ops; |
| 1301 | |
| 1302 | netdev->features = NETIF_F_IP_CSUM | NETIF_F_RXCSUM | |
| 1303 | NETIF_F_GSO_ROBUST; |
| 1304 | netdev->hw_features = NETIF_F_SG | |
| 1305 | NETIF_F_IPV6_CSUM | |
| 1306 | NETIF_F_TSO | NETIF_F_TSO6; |
| 1307 | |
| 1308 | /* |
| 1309 | * Assume that all hw features are available for now. This set |
| 1310 | * will be adjusted by the call to netdev_update_features() in |
| 1311 | * xennet_connect() which is the earliest point where we can |
| 1312 | * negotiate with the backend regarding supported features. |
| 1313 | */ |
| 1314 | netdev->features |= netdev->hw_features; |
| 1315 | |
| 1316 | netdev->ethtool_ops = &xennet_ethtool_ops; |
| 1317 | SET_NETDEV_DEV(netdev, &dev->dev); |
| 1318 | |
| 1319 | np->netdev = netdev; |
| 1320 | |
| 1321 | netif_carrier_off(netdev); |
| 1322 | |
| 1323 | return netdev; |
| 1324 | |
| 1325 | exit: |
| 1326 | xennet_free_netdev(netdev); |
| 1327 | return ERR_PTR(err); |
| 1328 | } |
| 1329 | |
| 1330 | /** |
| 1331 | * Entry point to this code when a new device is created. Allocate the basic |
| 1332 | * structures and the ring buffers for communication with the backend, and |
| 1333 | * inform the backend of the appropriate details for those. |
| 1334 | */ |
| 1335 | static int netfront_probe(struct xenbus_device *dev, |
| 1336 | const struct xenbus_device_id *id) |
| 1337 | { |
| 1338 | int err; |
| 1339 | struct net_device *netdev; |
| 1340 | struct netfront_info *info; |
| 1341 | |
| 1342 | netdev = xennet_create_dev(dev); |
| 1343 | if (IS_ERR(netdev)) { |
| 1344 | err = PTR_ERR(netdev); |
| 1345 | xenbus_dev_fatal(dev, err, "creating netdev"); |
| 1346 | return err; |
| 1347 | } |
| 1348 | |
| 1349 | info = netdev_priv(netdev); |
| 1350 | dev_set_drvdata(&dev->dev, info); |
| 1351 | #ifdef CONFIG_SYSFS |
| 1352 | info->netdev->sysfs_groups[0] = &xennet_dev_group; |
| 1353 | #endif |
| 1354 | err = register_netdev(info->netdev); |
| 1355 | if (err) { |
| 1356 | pr_warn("%s: register_netdev err=%d\n", __func__, err); |
| 1357 | goto fail; |
| 1358 | } |
| 1359 | |
| 1360 | return 0; |
| 1361 | |
| 1362 | fail: |
| 1363 | xennet_free_netdev(netdev); |
| 1364 | dev_set_drvdata(&dev->dev, NULL); |
| 1365 | return err; |
| 1366 | } |
| 1367 | |
| 1368 | static void xennet_end_access(int ref, void *page) |
| 1369 | { |
| 1370 | /* This frees the page as a side-effect */ |
| 1371 | if (ref != GRANT_INVALID_REF) |
| 1372 | gnttab_end_foreign_access(ref, 0, (unsigned long)page); |
| 1373 | } |
| 1374 | |
| 1375 | static void xennet_disconnect_backend(struct netfront_info *info) |
| 1376 | { |
| 1377 | unsigned int i = 0; |
| 1378 | unsigned int num_queues = info->netdev->real_num_tx_queues; |
| 1379 | |
| 1380 | netif_carrier_off(info->netdev); |
| 1381 | |
| 1382 | for (i = 0; i < num_queues && info->queues; ++i) { |
| 1383 | struct netfront_queue *queue = &info->queues[i]; |
| 1384 | |
| 1385 | if (queue->tx_irq && (queue->tx_irq == queue->rx_irq)) |
| 1386 | unbind_from_irqhandler(queue->tx_irq, queue); |
| 1387 | if (queue->tx_irq && (queue->tx_irq != queue->rx_irq)) { |
| 1388 | unbind_from_irqhandler(queue->tx_irq, queue); |
| 1389 | unbind_from_irqhandler(queue->rx_irq, queue); |
| 1390 | } |
| 1391 | queue->tx_evtchn = queue->rx_evtchn = 0; |
| 1392 | queue->tx_irq = queue->rx_irq = 0; |
| 1393 | |
| 1394 | if (netif_running(info->netdev)) |
| 1395 | napi_synchronize(&queue->napi); |
| 1396 | |
| 1397 | xennet_release_tx_bufs(queue); |
| 1398 | xennet_release_rx_bufs(queue); |
| 1399 | gnttab_free_grant_references(queue->gref_tx_head); |
| 1400 | gnttab_free_grant_references(queue->gref_rx_head); |
| 1401 | |
| 1402 | /* End access and free the pages */ |
| 1403 | xennet_end_access(queue->tx_ring_ref, queue->tx.sring); |
| 1404 | xennet_end_access(queue->rx_ring_ref, queue->rx.sring); |
| 1405 | |
| 1406 | queue->tx_ring_ref = GRANT_INVALID_REF; |
| 1407 | queue->rx_ring_ref = GRANT_INVALID_REF; |
| 1408 | queue->tx.sring = NULL; |
| 1409 | queue->rx.sring = NULL; |
| 1410 | } |
| 1411 | } |
| 1412 | |
| 1413 | /** |
| 1414 | * We are reconnecting to the backend, due to a suspend/resume, or a backend |
| 1415 | * driver restart. We tear down our netif structure and recreate it, but |
| 1416 | * leave the device-layer structures intact so that this is transparent to the |
| 1417 | * rest of the kernel. |
| 1418 | */ |
| 1419 | static int netfront_resume(struct xenbus_device *dev) |
| 1420 | { |
| 1421 | struct netfront_info *info = dev_get_drvdata(&dev->dev); |
| 1422 | |
| 1423 | dev_dbg(&dev->dev, "%s\n", dev->nodename); |
| 1424 | |
| 1425 | xennet_disconnect_backend(info); |
| 1426 | return 0; |
| 1427 | } |
| 1428 | |
| 1429 | static int xen_net_read_mac(struct xenbus_device *dev, u8 mac[]) |
| 1430 | { |
| 1431 | char *s, *e, *macstr; |
| 1432 | int i; |
| 1433 | |
| 1434 | macstr = s = xenbus_read(XBT_NIL, dev->nodename, "mac", NULL); |
| 1435 | if (IS_ERR(macstr)) |
| 1436 | return PTR_ERR(macstr); |
| 1437 | |
| 1438 | for (i = 0; i < ETH_ALEN; i++) { |
| 1439 | mac[i] = simple_strtoul(s, &e, 16); |
| 1440 | if ((s == e) || (*e != ((i == ETH_ALEN-1) ? '\0' : ':'))) { |
| 1441 | kfree(macstr); |
| 1442 | return -ENOENT; |
| 1443 | } |
| 1444 | s = e+1; |
| 1445 | } |
| 1446 | |
| 1447 | kfree(macstr); |
| 1448 | return 0; |
| 1449 | } |
| 1450 | |
| 1451 | static int setup_netfront_single(struct netfront_queue *queue) |
| 1452 | { |
| 1453 | int err; |
| 1454 | |
| 1455 | err = xenbus_alloc_evtchn(queue->info->xbdev, &queue->tx_evtchn); |
| 1456 | if (err < 0) |
| 1457 | goto fail; |
| 1458 | |
| 1459 | err = bind_evtchn_to_irqhandler(queue->tx_evtchn, |
| 1460 | xennet_interrupt, |
| 1461 | 0, queue->info->netdev->name, queue); |
| 1462 | if (err < 0) |
| 1463 | goto bind_fail; |
| 1464 | queue->rx_evtchn = queue->tx_evtchn; |
| 1465 | queue->rx_irq = queue->tx_irq = err; |
| 1466 | |
| 1467 | return 0; |
| 1468 | |
| 1469 | bind_fail: |
| 1470 | xenbus_free_evtchn(queue->info->xbdev, queue->tx_evtchn); |
| 1471 | queue->tx_evtchn = 0; |
| 1472 | fail: |
| 1473 | return err; |
| 1474 | } |
| 1475 | |
| 1476 | static int setup_netfront_split(struct netfront_queue *queue) |
| 1477 | { |
| 1478 | int err; |
| 1479 | |
| 1480 | err = xenbus_alloc_evtchn(queue->info->xbdev, &queue->tx_evtchn); |
| 1481 | if (err < 0) |
| 1482 | goto fail; |
| 1483 | err = xenbus_alloc_evtchn(queue->info->xbdev, &queue->rx_evtchn); |
| 1484 | if (err < 0) |
| 1485 | goto alloc_rx_evtchn_fail; |
| 1486 | |
| 1487 | snprintf(queue->tx_irq_name, sizeof(queue->tx_irq_name), |
| 1488 | "%s-tx", queue->name); |
| 1489 | err = bind_evtchn_to_irqhandler(queue->tx_evtchn, |
| 1490 | xennet_tx_interrupt, |
| 1491 | 0, queue->tx_irq_name, queue); |
| 1492 | if (err < 0) |
| 1493 | goto bind_tx_fail; |
| 1494 | queue->tx_irq = err; |
| 1495 | |
| 1496 | snprintf(queue->rx_irq_name, sizeof(queue->rx_irq_name), |
| 1497 | "%s-rx", queue->name); |
| 1498 | err = bind_evtchn_to_irqhandler(queue->rx_evtchn, |
| 1499 | xennet_rx_interrupt, |
| 1500 | 0, queue->rx_irq_name, queue); |
| 1501 | if (err < 0) |
| 1502 | goto bind_rx_fail; |
| 1503 | queue->rx_irq = err; |
| 1504 | |
| 1505 | return 0; |
| 1506 | |
| 1507 | bind_rx_fail: |
| 1508 | unbind_from_irqhandler(queue->tx_irq, queue); |
| 1509 | queue->tx_irq = 0; |
| 1510 | bind_tx_fail: |
| 1511 | xenbus_free_evtchn(queue->info->xbdev, queue->rx_evtchn); |
| 1512 | queue->rx_evtchn = 0; |
| 1513 | alloc_rx_evtchn_fail: |
| 1514 | xenbus_free_evtchn(queue->info->xbdev, queue->tx_evtchn); |
| 1515 | queue->tx_evtchn = 0; |
| 1516 | fail: |
| 1517 | return err; |
| 1518 | } |
| 1519 | |
| 1520 | static int setup_netfront(struct xenbus_device *dev, |
| 1521 | struct netfront_queue *queue, unsigned int feature_split_evtchn) |
| 1522 | { |
| 1523 | struct xen_netif_tx_sring *txs; |
| 1524 | struct xen_netif_rx_sring *rxs; |
| 1525 | grant_ref_t gref; |
| 1526 | int err; |
| 1527 | |
| 1528 | queue->tx_ring_ref = GRANT_INVALID_REF; |
| 1529 | queue->rx_ring_ref = GRANT_INVALID_REF; |
| 1530 | queue->rx.sring = NULL; |
| 1531 | queue->tx.sring = NULL; |
| 1532 | |
| 1533 | txs = (struct xen_netif_tx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH); |
| 1534 | if (!txs) { |
| 1535 | err = -ENOMEM; |
| 1536 | xenbus_dev_fatal(dev, err, "allocating tx ring page"); |
| 1537 | goto fail; |
| 1538 | } |
| 1539 | SHARED_RING_INIT(txs); |
| 1540 | FRONT_RING_INIT(&queue->tx, txs, XEN_PAGE_SIZE); |
| 1541 | |
| 1542 | err = xenbus_grant_ring(dev, txs, 1, &gref); |
| 1543 | if (err < 0) |
| 1544 | goto grant_tx_ring_fail; |
| 1545 | queue->tx_ring_ref = gref; |
| 1546 | |
| 1547 | rxs = (struct xen_netif_rx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH); |
| 1548 | if (!rxs) { |
| 1549 | err = -ENOMEM; |
| 1550 | xenbus_dev_fatal(dev, err, "allocating rx ring page"); |
| 1551 | goto alloc_rx_ring_fail; |
| 1552 | } |
| 1553 | SHARED_RING_INIT(rxs); |
| 1554 | FRONT_RING_INIT(&queue->rx, rxs, XEN_PAGE_SIZE); |
| 1555 | |
| 1556 | err = xenbus_grant_ring(dev, rxs, 1, &gref); |
| 1557 | if (err < 0) |
| 1558 | goto grant_rx_ring_fail; |
| 1559 | queue->rx_ring_ref = gref; |
| 1560 | |
| 1561 | if (feature_split_evtchn) |
| 1562 | err = setup_netfront_split(queue); |
| 1563 | /* setup single event channel if |
| 1564 | * a) feature-split-event-channels == 0 |
| 1565 | * b) feature-split-event-channels == 1 but failed to setup |
| 1566 | */ |
| 1567 | if (!feature_split_evtchn || (feature_split_evtchn && err)) |
| 1568 | err = setup_netfront_single(queue); |
| 1569 | |
| 1570 | if (err) |
| 1571 | goto alloc_evtchn_fail; |
| 1572 | |
| 1573 | return 0; |
| 1574 | |
| 1575 | /* If we fail to setup netfront, it is safe to just revoke access to |
| 1576 | * granted pages because backend is not accessing it at this point. |
| 1577 | */ |
| 1578 | alloc_evtchn_fail: |
| 1579 | gnttab_end_foreign_access_ref(queue->rx_ring_ref, 0); |
| 1580 | grant_rx_ring_fail: |
| 1581 | free_page((unsigned long)rxs); |
| 1582 | alloc_rx_ring_fail: |
| 1583 | gnttab_end_foreign_access_ref(queue->tx_ring_ref, 0); |
| 1584 | grant_tx_ring_fail: |
| 1585 | free_page((unsigned long)txs); |
| 1586 | fail: |
| 1587 | return err; |
| 1588 | } |
| 1589 | |
| 1590 | /* Queue-specific initialisation |
| 1591 | * This used to be done in xennet_create_dev() but must now |
| 1592 | * be run per-queue. |
| 1593 | */ |
| 1594 | static int xennet_init_queue(struct netfront_queue *queue) |
| 1595 | { |
| 1596 | unsigned short i; |
| 1597 | int err = 0; |
| 1598 | |
| 1599 | spin_lock_init(&queue->tx_lock); |
| 1600 | spin_lock_init(&queue->rx_lock); |
| 1601 | |
| 1602 | setup_timer(&queue->rx_refill_timer, rx_refill_timeout, |
| 1603 | (unsigned long)queue); |
| 1604 | |
| 1605 | snprintf(queue->name, sizeof(queue->name), "%s-q%u", |
| 1606 | queue->info->netdev->name, queue->id); |
| 1607 | |
| 1608 | /* Initialise tx_skbs as a free chain containing every entry. */ |
| 1609 | queue->tx_skb_freelist = 0; |
| 1610 | for (i = 0; i < NET_TX_RING_SIZE; i++) { |
| 1611 | skb_entry_set_link(&queue->tx_skbs[i], i+1); |
| 1612 | queue->grant_tx_ref[i] = GRANT_INVALID_REF; |
| 1613 | queue->grant_tx_page[i] = NULL; |
| 1614 | } |
| 1615 | |
| 1616 | /* Clear out rx_skbs */ |
| 1617 | for (i = 0; i < NET_RX_RING_SIZE; i++) { |
| 1618 | queue->rx_skbs[i] = NULL; |
| 1619 | queue->grant_rx_ref[i] = GRANT_INVALID_REF; |
| 1620 | } |
| 1621 | |
| 1622 | /* A grant for every tx ring slot */ |
| 1623 | if (gnttab_alloc_grant_references(NET_TX_RING_SIZE, |
| 1624 | &queue->gref_tx_head) < 0) { |
| 1625 | pr_alert("can't alloc tx grant refs\n"); |
| 1626 | err = -ENOMEM; |
| 1627 | goto exit; |
| 1628 | } |
| 1629 | |
| 1630 | /* A grant for every rx ring slot */ |
| 1631 | if (gnttab_alloc_grant_references(NET_RX_RING_SIZE, |
| 1632 | &queue->gref_rx_head) < 0) { |
| 1633 | pr_alert("can't alloc rx grant refs\n"); |
| 1634 | err = -ENOMEM; |
| 1635 | goto exit_free_tx; |
| 1636 | } |
| 1637 | |
| 1638 | return 0; |
| 1639 | |
| 1640 | exit_free_tx: |
| 1641 | gnttab_free_grant_references(queue->gref_tx_head); |
| 1642 | exit: |
| 1643 | return err; |
| 1644 | } |
| 1645 | |
| 1646 | static int write_queue_xenstore_keys(struct netfront_queue *queue, |
| 1647 | struct xenbus_transaction *xbt, int write_hierarchical) |
| 1648 | { |
| 1649 | /* Write the queue-specific keys into XenStore in the traditional |
| 1650 | * way for a single queue, or in a queue subkeys for multiple |
| 1651 | * queues. |
| 1652 | */ |
| 1653 | struct xenbus_device *dev = queue->info->xbdev; |
| 1654 | int err; |
| 1655 | const char *message; |
| 1656 | char *path; |
| 1657 | size_t pathsize; |
| 1658 | |
| 1659 | /* Choose the correct place to write the keys */ |
| 1660 | if (write_hierarchical) { |
| 1661 | pathsize = strlen(dev->nodename) + 10; |
| 1662 | path = kzalloc(pathsize, GFP_KERNEL); |
| 1663 | if (!path) { |
| 1664 | err = -ENOMEM; |
| 1665 | message = "out of memory while writing ring references"; |
| 1666 | goto error; |
| 1667 | } |
| 1668 | snprintf(path, pathsize, "%s/queue-%u", |
| 1669 | dev->nodename, queue->id); |
| 1670 | } else { |
| 1671 | path = (char *)dev->nodename; |
| 1672 | } |
| 1673 | |
| 1674 | /* Write ring references */ |
| 1675 | err = xenbus_printf(*xbt, path, "tx-ring-ref", "%u", |
| 1676 | queue->tx_ring_ref); |
| 1677 | if (err) { |
| 1678 | message = "writing tx-ring-ref"; |
| 1679 | goto error; |
| 1680 | } |
| 1681 | |
| 1682 | err = xenbus_printf(*xbt, path, "rx-ring-ref", "%u", |
| 1683 | queue->rx_ring_ref); |
| 1684 | if (err) { |
| 1685 | message = "writing rx-ring-ref"; |
| 1686 | goto error; |
| 1687 | } |
| 1688 | |
| 1689 | /* Write event channels; taking into account both shared |
| 1690 | * and split event channel scenarios. |
| 1691 | */ |
| 1692 | if (queue->tx_evtchn == queue->rx_evtchn) { |
| 1693 | /* Shared event channel */ |
| 1694 | err = xenbus_printf(*xbt, path, |
| 1695 | "event-channel", "%u", queue->tx_evtchn); |
| 1696 | if (err) { |
| 1697 | message = "writing event-channel"; |
| 1698 | goto error; |
| 1699 | } |
| 1700 | } else { |
| 1701 | /* Split event channels */ |
| 1702 | err = xenbus_printf(*xbt, path, |
| 1703 | "event-channel-tx", "%u", queue->tx_evtchn); |
| 1704 | if (err) { |
| 1705 | message = "writing event-channel-tx"; |
| 1706 | goto error; |
| 1707 | } |
| 1708 | |
| 1709 | err = xenbus_printf(*xbt, path, |
| 1710 | "event-channel-rx", "%u", queue->rx_evtchn); |
| 1711 | if (err) { |
| 1712 | message = "writing event-channel-rx"; |
| 1713 | goto error; |
| 1714 | } |
| 1715 | } |
| 1716 | |
| 1717 | if (write_hierarchical) |
| 1718 | kfree(path); |
| 1719 | return 0; |
| 1720 | |
| 1721 | error: |
| 1722 | if (write_hierarchical) |
| 1723 | kfree(path); |
| 1724 | xenbus_dev_fatal(dev, err, "%s", message); |
| 1725 | return err; |
| 1726 | } |
| 1727 | |
| 1728 | static void xennet_destroy_queues(struct netfront_info *info) |
| 1729 | { |
| 1730 | unsigned int i; |
| 1731 | |
| 1732 | rtnl_lock(); |
| 1733 | |
| 1734 | for (i = 0; i < info->netdev->real_num_tx_queues; i++) { |
| 1735 | struct netfront_queue *queue = &info->queues[i]; |
| 1736 | |
| 1737 | if (netif_running(info->netdev)) |
| 1738 | napi_disable(&queue->napi); |
| 1739 | del_timer_sync(&queue->rx_refill_timer); |
| 1740 | netif_napi_del(&queue->napi); |
| 1741 | } |
| 1742 | |
| 1743 | rtnl_unlock(); |
| 1744 | |
| 1745 | kfree(info->queues); |
| 1746 | info->queues = NULL; |
| 1747 | } |
| 1748 | |
| 1749 | static int xennet_create_queues(struct netfront_info *info, |
| 1750 | unsigned int *num_queues) |
| 1751 | { |
| 1752 | unsigned int i; |
| 1753 | int ret; |
| 1754 | |
| 1755 | info->queues = kcalloc(*num_queues, sizeof(struct netfront_queue), |
| 1756 | GFP_KERNEL); |
| 1757 | if (!info->queues) |
| 1758 | return -ENOMEM; |
| 1759 | |
| 1760 | rtnl_lock(); |
| 1761 | |
| 1762 | for (i = 0; i < *num_queues; i++) { |
| 1763 | struct netfront_queue *queue = &info->queues[i]; |
| 1764 | |
| 1765 | queue->id = i; |
| 1766 | queue->info = info; |
| 1767 | |
| 1768 | ret = xennet_init_queue(queue); |
| 1769 | if (ret < 0) { |
| 1770 | dev_warn(&info->netdev->dev, |
| 1771 | "only created %d queues\n", i); |
| 1772 | *num_queues = i; |
| 1773 | break; |
| 1774 | } |
| 1775 | |
| 1776 | netif_napi_add(queue->info->netdev, &queue->napi, |
| 1777 | xennet_poll, 64); |
| 1778 | if (netif_running(info->netdev)) |
| 1779 | napi_enable(&queue->napi); |
| 1780 | } |
| 1781 | |
| 1782 | netif_set_real_num_tx_queues(info->netdev, *num_queues); |
| 1783 | |
| 1784 | rtnl_unlock(); |
| 1785 | |
| 1786 | if (*num_queues == 0) { |
| 1787 | dev_err(&info->netdev->dev, "no queues\n"); |
| 1788 | return -EINVAL; |
| 1789 | } |
| 1790 | return 0; |
| 1791 | } |
| 1792 | |
| 1793 | /* Common code used when first setting up, and when resuming. */ |
| 1794 | static int talk_to_netback(struct xenbus_device *dev, |
| 1795 | struct netfront_info *info) |
| 1796 | { |
| 1797 | const char *message; |
| 1798 | struct xenbus_transaction xbt; |
| 1799 | int err; |
| 1800 | unsigned int feature_split_evtchn; |
| 1801 | unsigned int i = 0; |
| 1802 | unsigned int max_queues = 0; |
| 1803 | struct netfront_queue *queue = NULL; |
| 1804 | unsigned int num_queues = 1; |
| 1805 | |
| 1806 | info->netdev->irq = 0; |
| 1807 | |
| 1808 | /* Check if backend supports multiple queues */ |
| 1809 | err = xenbus_scanf(XBT_NIL, info->xbdev->otherend, |
| 1810 | "multi-queue-max-queues", "%u", &max_queues); |
| 1811 | if (err < 0) |
| 1812 | max_queues = 1; |
| 1813 | num_queues = min(max_queues, xennet_max_queues); |
| 1814 | |
| 1815 | /* Check feature-split-event-channels */ |
| 1816 | err = xenbus_scanf(XBT_NIL, info->xbdev->otherend, |
| 1817 | "feature-split-event-channels", "%u", |
| 1818 | &feature_split_evtchn); |
| 1819 | if (err < 0) |
| 1820 | feature_split_evtchn = 0; |
| 1821 | |
| 1822 | /* Read mac addr. */ |
| 1823 | err = xen_net_read_mac(dev, info->netdev->dev_addr); |
| 1824 | if (err) { |
| 1825 | xenbus_dev_fatal(dev, err, "parsing %s/mac", dev->nodename); |
| 1826 | goto out; |
| 1827 | } |
| 1828 | |
| 1829 | if (info->queues) |
| 1830 | xennet_destroy_queues(info); |
| 1831 | |
| 1832 | err = xennet_create_queues(info, &num_queues); |
| 1833 | if (err < 0) |
| 1834 | goto destroy_ring; |
| 1835 | |
| 1836 | /* Create shared ring, alloc event channel -- for each queue */ |
| 1837 | for (i = 0; i < num_queues; ++i) { |
| 1838 | queue = &info->queues[i]; |
| 1839 | err = setup_netfront(dev, queue, feature_split_evtchn); |
| 1840 | if (err) { |
| 1841 | /* setup_netfront() will tidy up the current |
| 1842 | * queue on error, but we need to clean up |
| 1843 | * those already allocated. |
| 1844 | */ |
| 1845 | if (i > 0) { |
| 1846 | rtnl_lock(); |
| 1847 | netif_set_real_num_tx_queues(info->netdev, i); |
| 1848 | rtnl_unlock(); |
| 1849 | goto destroy_ring; |
| 1850 | } else { |
| 1851 | goto out; |
| 1852 | } |
| 1853 | } |
| 1854 | } |
| 1855 | |
| 1856 | again: |
| 1857 | err = xenbus_transaction_start(&xbt); |
| 1858 | if (err) { |
| 1859 | xenbus_dev_fatal(dev, err, "starting transaction"); |
| 1860 | goto destroy_ring; |
| 1861 | } |
| 1862 | |
| 1863 | if (xenbus_exists(XBT_NIL, |
| 1864 | info->xbdev->otherend, "multi-queue-max-queues")) { |
| 1865 | /* Write the number of queues */ |
| 1866 | err = xenbus_printf(xbt, dev->nodename, |
| 1867 | "multi-queue-num-queues", "%u", num_queues); |
| 1868 | if (err) { |
| 1869 | message = "writing multi-queue-num-queues"; |
| 1870 | goto abort_transaction_no_dev_fatal; |
| 1871 | } |
| 1872 | } |
| 1873 | |
| 1874 | if (num_queues == 1) { |
| 1875 | err = write_queue_xenstore_keys(&info->queues[0], &xbt, 0); /* flat */ |
| 1876 | if (err) |
| 1877 | goto abort_transaction_no_dev_fatal; |
| 1878 | } else { |
| 1879 | /* Write the keys for each queue */ |
| 1880 | for (i = 0; i < num_queues; ++i) { |
| 1881 | queue = &info->queues[i]; |
| 1882 | err = write_queue_xenstore_keys(queue, &xbt, 1); /* hierarchical */ |
| 1883 | if (err) |
| 1884 | goto abort_transaction_no_dev_fatal; |
| 1885 | } |
| 1886 | } |
| 1887 | |
| 1888 | /* The remaining keys are not queue-specific */ |
| 1889 | err = xenbus_printf(xbt, dev->nodename, "request-rx-copy", "%u", |
| 1890 | 1); |
| 1891 | if (err) { |
| 1892 | message = "writing request-rx-copy"; |
| 1893 | goto abort_transaction; |
| 1894 | } |
| 1895 | |
| 1896 | err = xenbus_printf(xbt, dev->nodename, "feature-rx-notify", "%d", 1); |
| 1897 | if (err) { |
| 1898 | message = "writing feature-rx-notify"; |
| 1899 | goto abort_transaction; |
| 1900 | } |
| 1901 | |
| 1902 | err = xenbus_printf(xbt, dev->nodename, "feature-sg", "%d", 1); |
| 1903 | if (err) { |
| 1904 | message = "writing feature-sg"; |
| 1905 | goto abort_transaction; |
| 1906 | } |
| 1907 | |
| 1908 | err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv4", "%d", 1); |
| 1909 | if (err) { |
| 1910 | message = "writing feature-gso-tcpv4"; |
| 1911 | goto abort_transaction; |
| 1912 | } |
| 1913 | |
| 1914 | err = xenbus_write(xbt, dev->nodename, "feature-gso-tcpv6", "1"); |
| 1915 | if (err) { |
| 1916 | message = "writing feature-gso-tcpv6"; |
| 1917 | goto abort_transaction; |
| 1918 | } |
| 1919 | |
| 1920 | err = xenbus_write(xbt, dev->nodename, "feature-ipv6-csum-offload", |
| 1921 | "1"); |
| 1922 | if (err) { |
| 1923 | message = "writing feature-ipv6-csum-offload"; |
| 1924 | goto abort_transaction; |
| 1925 | } |
| 1926 | |
| 1927 | err = xenbus_transaction_end(xbt, 0); |
| 1928 | if (err) { |
| 1929 | if (err == -EAGAIN) |
| 1930 | goto again; |
| 1931 | xenbus_dev_fatal(dev, err, "completing transaction"); |
| 1932 | goto destroy_ring; |
| 1933 | } |
| 1934 | |
| 1935 | return 0; |
| 1936 | |
| 1937 | abort_transaction: |
| 1938 | xenbus_dev_fatal(dev, err, "%s", message); |
| 1939 | abort_transaction_no_dev_fatal: |
| 1940 | xenbus_transaction_end(xbt, 1); |
| 1941 | destroy_ring: |
| 1942 | xennet_disconnect_backend(info); |
| 1943 | kfree(info->queues); |
| 1944 | info->queues = NULL; |
| 1945 | out: |
| 1946 | return err; |
| 1947 | } |
| 1948 | |
| 1949 | static int xennet_connect(struct net_device *dev) |
| 1950 | { |
| 1951 | struct netfront_info *np = netdev_priv(dev); |
| 1952 | unsigned int num_queues = 0; |
| 1953 | int err; |
| 1954 | unsigned int feature_rx_copy; |
| 1955 | unsigned int j = 0; |
| 1956 | struct netfront_queue *queue = NULL; |
| 1957 | |
| 1958 | err = xenbus_scanf(XBT_NIL, np->xbdev->otherend, |
| 1959 | "feature-rx-copy", "%u", &feature_rx_copy); |
| 1960 | if (err != 1) |
| 1961 | feature_rx_copy = 0; |
| 1962 | |
| 1963 | if (!feature_rx_copy) { |
| 1964 | dev_info(&dev->dev, |
| 1965 | "backend does not support copying receive path\n"); |
| 1966 | return -ENODEV; |
| 1967 | } |
| 1968 | |
| 1969 | err = talk_to_netback(np->xbdev, np); |
| 1970 | if (err) |
| 1971 | return err; |
| 1972 | |
| 1973 | /* talk_to_netback() sets the correct number of queues */ |
| 1974 | num_queues = dev->real_num_tx_queues; |
| 1975 | |
| 1976 | rtnl_lock(); |
| 1977 | netdev_update_features(dev); |
| 1978 | rtnl_unlock(); |
| 1979 | |
| 1980 | /* |
| 1981 | * All public and private state should now be sane. Get |
| 1982 | * ready to start sending and receiving packets and give the driver |
| 1983 | * domain a kick because we've probably just requeued some |
| 1984 | * packets. |
| 1985 | */ |
| 1986 | netif_carrier_on(np->netdev); |
| 1987 | for (j = 0; j < num_queues; ++j) { |
| 1988 | queue = &np->queues[j]; |
| 1989 | |
| 1990 | notify_remote_via_irq(queue->tx_irq); |
| 1991 | if (queue->tx_irq != queue->rx_irq) |
| 1992 | notify_remote_via_irq(queue->rx_irq); |
| 1993 | |
| 1994 | spin_lock_irq(&queue->tx_lock); |
| 1995 | xennet_tx_buf_gc(queue); |
| 1996 | spin_unlock_irq(&queue->tx_lock); |
| 1997 | |
| 1998 | spin_lock_bh(&queue->rx_lock); |
| 1999 | xennet_alloc_rx_buffers(queue); |
| 2000 | spin_unlock_bh(&queue->rx_lock); |
| 2001 | } |
| 2002 | |
| 2003 | return 0; |
| 2004 | } |
| 2005 | |
| 2006 | /** |
| 2007 | * Callback received when the backend's state changes. |
| 2008 | */ |
| 2009 | static void netback_changed(struct xenbus_device *dev, |
| 2010 | enum xenbus_state backend_state) |
| 2011 | { |
| 2012 | struct netfront_info *np = dev_get_drvdata(&dev->dev); |
| 2013 | struct net_device *netdev = np->netdev; |
| 2014 | |
| 2015 | dev_dbg(&dev->dev, "%s\n", xenbus_strstate(backend_state)); |
| 2016 | |
| 2017 | switch (backend_state) { |
| 2018 | case XenbusStateInitialising: |
| 2019 | case XenbusStateInitialised: |
| 2020 | case XenbusStateReconfiguring: |
| 2021 | case XenbusStateReconfigured: |
| 2022 | case XenbusStateUnknown: |
| 2023 | break; |
| 2024 | |
| 2025 | case XenbusStateInitWait: |
| 2026 | if (dev->state != XenbusStateInitialising) |
| 2027 | break; |
| 2028 | if (xennet_connect(netdev) != 0) |
| 2029 | break; |
| 2030 | xenbus_switch_state(dev, XenbusStateConnected); |
| 2031 | break; |
| 2032 | |
| 2033 | case XenbusStateConnected: |
| 2034 | netdev_notify_peers(netdev); |
| 2035 | break; |
| 2036 | |
| 2037 | case XenbusStateClosed: |
| 2038 | if (dev->state == XenbusStateClosed) |
| 2039 | break; |
| 2040 | /* Missed the backend's CLOSING state -- fallthrough */ |
| 2041 | case XenbusStateClosing: |
| 2042 | xenbus_frontend_closed(dev); |
| 2043 | break; |
| 2044 | } |
| 2045 | } |
| 2046 | |
| 2047 | static const struct xennet_stat { |
| 2048 | char name[ETH_GSTRING_LEN]; |
| 2049 | u16 offset; |
| 2050 | } xennet_stats[] = { |
| 2051 | { |
| 2052 | "rx_gso_checksum_fixup", |
| 2053 | offsetof(struct netfront_info, rx_gso_checksum_fixup) |
| 2054 | }, |
| 2055 | }; |
| 2056 | |
| 2057 | static int xennet_get_sset_count(struct net_device *dev, int string_set) |
| 2058 | { |
| 2059 | switch (string_set) { |
| 2060 | case ETH_SS_STATS: |
| 2061 | return ARRAY_SIZE(xennet_stats); |
| 2062 | default: |
| 2063 | return -EINVAL; |
| 2064 | } |
| 2065 | } |
| 2066 | |
| 2067 | static void xennet_get_ethtool_stats(struct net_device *dev, |
| 2068 | struct ethtool_stats *stats, u64 * data) |
| 2069 | { |
| 2070 | void *np = netdev_priv(dev); |
| 2071 | int i; |
| 2072 | |
| 2073 | for (i = 0; i < ARRAY_SIZE(xennet_stats); i++) |
| 2074 | data[i] = atomic_read((atomic_t *)(np + xennet_stats[i].offset)); |
| 2075 | } |
| 2076 | |
| 2077 | static void xennet_get_strings(struct net_device *dev, u32 stringset, u8 * data) |
| 2078 | { |
| 2079 | int i; |
| 2080 | |
| 2081 | switch (stringset) { |
| 2082 | case ETH_SS_STATS: |
| 2083 | for (i = 0; i < ARRAY_SIZE(xennet_stats); i++) |
| 2084 | memcpy(data + i * ETH_GSTRING_LEN, |
| 2085 | xennet_stats[i].name, ETH_GSTRING_LEN); |
| 2086 | break; |
| 2087 | } |
| 2088 | } |
| 2089 | |
| 2090 | static const struct ethtool_ops xennet_ethtool_ops = |
| 2091 | { |
| 2092 | .get_link = ethtool_op_get_link, |
| 2093 | |
| 2094 | .get_sset_count = xennet_get_sset_count, |
| 2095 | .get_ethtool_stats = xennet_get_ethtool_stats, |
| 2096 | .get_strings = xennet_get_strings, |
| 2097 | }; |
| 2098 | |
| 2099 | #ifdef CONFIG_SYSFS |
| 2100 | static ssize_t show_rxbuf(struct device *dev, |
| 2101 | struct device_attribute *attr, char *buf) |
| 2102 | { |
| 2103 | return sprintf(buf, "%lu\n", NET_RX_RING_SIZE); |
| 2104 | } |
| 2105 | |
| 2106 | static ssize_t store_rxbuf(struct device *dev, |
| 2107 | struct device_attribute *attr, |
| 2108 | const char *buf, size_t len) |
| 2109 | { |
| 2110 | char *endp; |
| 2111 | unsigned long target; |
| 2112 | |
| 2113 | if (!capable(CAP_NET_ADMIN)) |
| 2114 | return -EPERM; |
| 2115 | |
| 2116 | target = simple_strtoul(buf, &endp, 0); |
| 2117 | if (endp == buf) |
| 2118 | return -EBADMSG; |
| 2119 | |
| 2120 | /* rxbuf_min and rxbuf_max are no longer configurable. */ |
| 2121 | |
| 2122 | return len; |
| 2123 | } |
| 2124 | |
| 2125 | static DEVICE_ATTR(rxbuf_min, S_IRUGO|S_IWUSR, show_rxbuf, store_rxbuf); |
| 2126 | static DEVICE_ATTR(rxbuf_max, S_IRUGO|S_IWUSR, show_rxbuf, store_rxbuf); |
| 2127 | static DEVICE_ATTR(rxbuf_cur, S_IRUGO, show_rxbuf, NULL); |
| 2128 | |
| 2129 | static struct attribute *xennet_dev_attrs[] = { |
| 2130 | &dev_attr_rxbuf_min.attr, |
| 2131 | &dev_attr_rxbuf_max.attr, |
| 2132 | &dev_attr_rxbuf_cur.attr, |
| 2133 | NULL |
| 2134 | }; |
| 2135 | |
| 2136 | static const struct attribute_group xennet_dev_group = { |
| 2137 | .attrs = xennet_dev_attrs |
| 2138 | }; |
| 2139 | #endif /* CONFIG_SYSFS */ |
| 2140 | |
| 2141 | static int xennet_remove(struct xenbus_device *dev) |
| 2142 | { |
| 2143 | struct netfront_info *info = dev_get_drvdata(&dev->dev); |
| 2144 | |
| 2145 | dev_dbg(&dev->dev, "%s\n", dev->nodename); |
| 2146 | |
| 2147 | xennet_disconnect_backend(info); |
| 2148 | |
| 2149 | unregister_netdev(info->netdev); |
| 2150 | |
| 2151 | if (info->queues) |
| 2152 | xennet_destroy_queues(info); |
| 2153 | xennet_free_netdev(info->netdev); |
| 2154 | |
| 2155 | return 0; |
| 2156 | } |
| 2157 | |
| 2158 | static const struct xenbus_device_id netfront_ids[] = { |
| 2159 | { "vif" }, |
| 2160 | { "" } |
| 2161 | }; |
| 2162 | |
| 2163 | static struct xenbus_driver netfront_driver = { |
| 2164 | .ids = netfront_ids, |
| 2165 | .probe = netfront_probe, |
| 2166 | .remove = xennet_remove, |
| 2167 | .resume = netfront_resume, |
| 2168 | .otherend_changed = netback_changed, |
| 2169 | }; |
| 2170 | |
| 2171 | static int __init netif_init(void) |
| 2172 | { |
| 2173 | if (!xen_domain()) |
| 2174 | return -ENODEV; |
| 2175 | |
| 2176 | if (!xen_has_pv_nic_devices()) |
| 2177 | return -ENODEV; |
| 2178 | |
| 2179 | pr_info("Initialising Xen virtual ethernet driver\n"); |
| 2180 | |
| 2181 | /* Allow as many queues as there are CPUs if user has not |
| 2182 | * specified a value. |
| 2183 | */ |
| 2184 | if (xennet_max_queues == 0) |
| 2185 | xennet_max_queues = num_online_cpus(); |
| 2186 | |
| 2187 | return xenbus_register_frontend(&netfront_driver); |
| 2188 | } |
| 2189 | module_init(netif_init); |
| 2190 | |
| 2191 | |
| 2192 | static void __exit netif_exit(void) |
| 2193 | { |
| 2194 | xenbus_unregister_driver(&netfront_driver); |
| 2195 | } |
| 2196 | module_exit(netif_exit); |
| 2197 | |
| 2198 | MODULE_DESCRIPTION("Xen virtual network device frontend"); |
| 2199 | MODULE_LICENSE("GPL"); |
| 2200 | MODULE_ALIAS("xen:vif"); |
| 2201 | MODULE_ALIAS("xennet"); |