| 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 | #include <linux/module.h> |
| 33 | #include <linux/kernel.h> |
| 34 | #include <linux/netdevice.h> |
| 35 | #include <linux/etherdevice.h> |
| 36 | #include <linux/skbuff.h> |
| 37 | #include <linux/ethtool.h> |
| 38 | #include <linux/if_ether.h> |
| 39 | #include <linux/tcp.h> |
| 40 | #include <linux/udp.h> |
| 41 | #include <linux/moduleparam.h> |
| 42 | #include <linux/mm.h> |
| 43 | #include <net/ip.h> |
| 44 | |
| 45 | #include <xen/xenbus.h> |
| 46 | #include <xen/events.h> |
| 47 | #include <xen/page.h> |
| 48 | #include <xen/grant_table.h> |
| 49 | |
| 50 | #include <xen/interface/io/netif.h> |
| 51 | #include <xen/interface/memory.h> |
| 52 | #include <xen/interface/grant_table.h> |
| 53 | |
| 54 | static const struct ethtool_ops xennet_ethtool_ops; |
| 55 | |
| 56 | struct netfront_cb { |
| 57 | struct page *page; |
| 58 | unsigned offset; |
| 59 | }; |
| 60 | |
| 61 | #define NETFRONT_SKB_CB(skb) ((struct netfront_cb *)((skb)->cb)) |
| 62 | |
| 63 | #define RX_COPY_THRESHOLD 256 |
| 64 | |
| 65 | #define GRANT_INVALID_REF 0 |
| 66 | |
| 67 | #define NET_TX_RING_SIZE __RING_SIZE((struct xen_netif_tx_sring *)0, PAGE_SIZE) |
| 68 | #define NET_RX_RING_SIZE __RING_SIZE((struct xen_netif_rx_sring *)0, PAGE_SIZE) |
| 69 | #define TX_MAX_TARGET min_t(int, NET_RX_RING_SIZE, 256) |
| 70 | |
| 71 | struct netfront_info { |
| 72 | struct list_head list; |
| 73 | struct net_device *netdev; |
| 74 | |
| 75 | struct napi_struct napi; |
| 76 | |
| 77 | unsigned int evtchn; |
| 78 | struct xenbus_device *xbdev; |
| 79 | |
| 80 | spinlock_t tx_lock; |
| 81 | struct xen_netif_tx_front_ring tx; |
| 82 | int tx_ring_ref; |
| 83 | |
| 84 | /* |
| 85 | * {tx,rx}_skbs store outstanding skbuffs. Free tx_skb entries |
| 86 | * are linked from tx_skb_freelist through skb_entry.link. |
| 87 | * |
| 88 | * NB. Freelist index entries are always going to be less than |
| 89 | * PAGE_OFFSET, whereas pointers to skbs will always be equal or |
| 90 | * greater than PAGE_OFFSET: we use this property to distinguish |
| 91 | * them. |
| 92 | */ |
| 93 | union skb_entry { |
| 94 | struct sk_buff *skb; |
| 95 | unsigned long link; |
| 96 | } tx_skbs[NET_TX_RING_SIZE]; |
| 97 | grant_ref_t gref_tx_head; |
| 98 | grant_ref_t grant_tx_ref[NET_TX_RING_SIZE]; |
| 99 | unsigned tx_skb_freelist; |
| 100 | |
| 101 | spinlock_t rx_lock ____cacheline_aligned_in_smp; |
| 102 | struct xen_netif_rx_front_ring rx; |
| 103 | int rx_ring_ref; |
| 104 | |
| 105 | /* Receive-ring batched refills. */ |
| 106 | #define RX_MIN_TARGET 8 |
| 107 | #define RX_DFL_MIN_TARGET 64 |
| 108 | #define RX_MAX_TARGET min_t(int, NET_RX_RING_SIZE, 256) |
| 109 | unsigned rx_min_target, rx_max_target, rx_target; |
| 110 | struct sk_buff_head rx_batch; |
| 111 | |
| 112 | struct timer_list rx_refill_timer; |
| 113 | |
| 114 | struct sk_buff *rx_skbs[NET_RX_RING_SIZE]; |
| 115 | grant_ref_t gref_rx_head; |
| 116 | grant_ref_t grant_rx_ref[NET_RX_RING_SIZE]; |
| 117 | |
| 118 | unsigned long rx_pfn_array[NET_RX_RING_SIZE]; |
| 119 | struct multicall_entry rx_mcl[NET_RX_RING_SIZE+1]; |
| 120 | struct mmu_update rx_mmu[NET_RX_RING_SIZE]; |
| 121 | }; |
| 122 | |
| 123 | struct netfront_rx_info { |
| 124 | struct xen_netif_rx_response rx; |
| 125 | struct xen_netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX - 1]; |
| 126 | }; |
| 127 | |
| 128 | static void skb_entry_set_link(union skb_entry *list, unsigned short id) |
| 129 | { |
| 130 | list->link = id; |
| 131 | } |
| 132 | |
| 133 | static int skb_entry_is_link(const union skb_entry *list) |
| 134 | { |
| 135 | BUILD_BUG_ON(sizeof(list->skb) != sizeof(list->link)); |
| 136 | return ((unsigned long)list->skb < PAGE_OFFSET); |
| 137 | } |
| 138 | |
| 139 | /* |
| 140 | * Access macros for acquiring freeing slots in tx_skbs[]. |
| 141 | */ |
| 142 | |
| 143 | static void add_id_to_freelist(unsigned *head, union skb_entry *list, |
| 144 | unsigned short id) |
| 145 | { |
| 146 | skb_entry_set_link(&list[id], *head); |
| 147 | *head = id; |
| 148 | } |
| 149 | |
| 150 | static unsigned short get_id_from_freelist(unsigned *head, |
| 151 | union skb_entry *list) |
| 152 | { |
| 153 | unsigned int id = *head; |
| 154 | *head = list[id].link; |
| 155 | return id; |
| 156 | } |
| 157 | |
| 158 | static int xennet_rxidx(RING_IDX idx) |
| 159 | { |
| 160 | return idx & (NET_RX_RING_SIZE - 1); |
| 161 | } |
| 162 | |
| 163 | static struct sk_buff *xennet_get_rx_skb(struct netfront_info *np, |
| 164 | RING_IDX ri) |
| 165 | { |
| 166 | int i = xennet_rxidx(ri); |
| 167 | struct sk_buff *skb = np->rx_skbs[i]; |
| 168 | np->rx_skbs[i] = NULL; |
| 169 | return skb; |
| 170 | } |
| 171 | |
| 172 | static grant_ref_t xennet_get_rx_ref(struct netfront_info *np, |
| 173 | RING_IDX ri) |
| 174 | { |
| 175 | int i = xennet_rxidx(ri); |
| 176 | grant_ref_t ref = np->grant_rx_ref[i]; |
| 177 | np->grant_rx_ref[i] = GRANT_INVALID_REF; |
| 178 | return ref; |
| 179 | } |
| 180 | |
| 181 | #ifdef CONFIG_SYSFS |
| 182 | static int xennet_sysfs_addif(struct net_device *netdev); |
| 183 | static void xennet_sysfs_delif(struct net_device *netdev); |
| 184 | #else /* !CONFIG_SYSFS */ |
| 185 | #define xennet_sysfs_addif(dev) (0) |
| 186 | #define xennet_sysfs_delif(dev) do { } while (0) |
| 187 | #endif |
| 188 | |
| 189 | static int xennet_can_sg(struct net_device *dev) |
| 190 | { |
| 191 | return dev->features & NETIF_F_SG; |
| 192 | } |
| 193 | |
| 194 | |
| 195 | static void rx_refill_timeout(unsigned long data) |
| 196 | { |
| 197 | struct net_device *dev = (struct net_device *)data; |
| 198 | struct netfront_info *np = netdev_priv(dev); |
| 199 | napi_schedule(&np->napi); |
| 200 | } |
| 201 | |
| 202 | static int netfront_tx_slot_available(struct netfront_info *np) |
| 203 | { |
| 204 | return ((np->tx.req_prod_pvt - np->tx.rsp_cons) < |
| 205 | (TX_MAX_TARGET - MAX_SKB_FRAGS - 2)); |
| 206 | } |
| 207 | |
| 208 | static void xennet_maybe_wake_tx(struct net_device *dev) |
| 209 | { |
| 210 | struct netfront_info *np = netdev_priv(dev); |
| 211 | |
| 212 | if (unlikely(netif_queue_stopped(dev)) && |
| 213 | netfront_tx_slot_available(np) && |
| 214 | likely(netif_running(dev))) |
| 215 | netif_wake_queue(dev); |
| 216 | } |
| 217 | |
| 218 | static void xennet_alloc_rx_buffers(struct net_device *dev) |
| 219 | { |
| 220 | unsigned short id; |
| 221 | struct netfront_info *np = netdev_priv(dev); |
| 222 | struct sk_buff *skb; |
| 223 | struct page *page; |
| 224 | int i, batch_target, notify; |
| 225 | RING_IDX req_prod = np->rx.req_prod_pvt; |
| 226 | grant_ref_t ref; |
| 227 | unsigned long pfn; |
| 228 | void *vaddr; |
| 229 | struct xen_netif_rx_request *req; |
| 230 | |
| 231 | if (unlikely(!netif_carrier_ok(dev))) |
| 232 | return; |
| 233 | |
| 234 | /* |
| 235 | * Allocate skbuffs greedily, even though we batch updates to the |
| 236 | * receive ring. This creates a less bursty demand on the memory |
| 237 | * allocator, so should reduce the chance of failed allocation requests |
| 238 | * both for ourself and for other kernel subsystems. |
| 239 | */ |
| 240 | batch_target = np->rx_target - (req_prod - np->rx.rsp_cons); |
| 241 | for (i = skb_queue_len(&np->rx_batch); i < batch_target; i++) { |
| 242 | skb = __netdev_alloc_skb(dev, RX_COPY_THRESHOLD + NET_IP_ALIGN, |
| 243 | GFP_ATOMIC | __GFP_NOWARN); |
| 244 | if (unlikely(!skb)) |
| 245 | goto no_skb; |
| 246 | |
| 247 | /* Align ip header to a 16 bytes boundary */ |
| 248 | skb_reserve(skb, NET_IP_ALIGN); |
| 249 | |
| 250 | page = alloc_page(GFP_ATOMIC | __GFP_NOWARN); |
| 251 | if (!page) { |
| 252 | kfree_skb(skb); |
| 253 | no_skb: |
| 254 | /* Any skbuffs queued for refill? Force them out. */ |
| 255 | if (i != 0) |
| 256 | goto refill; |
| 257 | /* Could not allocate any skbuffs. Try again later. */ |
| 258 | mod_timer(&np->rx_refill_timer, |
| 259 | jiffies + (HZ/10)); |
| 260 | break; |
| 261 | } |
| 262 | |
| 263 | skb_shinfo(skb)->frags[0].page = page; |
| 264 | skb_shinfo(skb)->nr_frags = 1; |
| 265 | __skb_queue_tail(&np->rx_batch, skb); |
| 266 | } |
| 267 | |
| 268 | /* Is the batch large enough to be worthwhile? */ |
| 269 | if (i < (np->rx_target/2)) { |
| 270 | if (req_prod > np->rx.sring->req_prod) |
| 271 | goto push; |
| 272 | return; |
| 273 | } |
| 274 | |
| 275 | /* Adjust our fill target if we risked running out of buffers. */ |
| 276 | if (((req_prod - np->rx.sring->rsp_prod) < (np->rx_target / 4)) && |
| 277 | ((np->rx_target *= 2) > np->rx_max_target)) |
| 278 | np->rx_target = np->rx_max_target; |
| 279 | |
| 280 | refill: |
| 281 | for (i = 0; ; i++) { |
| 282 | skb = __skb_dequeue(&np->rx_batch); |
| 283 | if (skb == NULL) |
| 284 | break; |
| 285 | |
| 286 | skb->dev = dev; |
| 287 | |
| 288 | id = xennet_rxidx(req_prod + i); |
| 289 | |
| 290 | BUG_ON(np->rx_skbs[id]); |
| 291 | np->rx_skbs[id] = skb; |
| 292 | |
| 293 | ref = gnttab_claim_grant_reference(&np->gref_rx_head); |
| 294 | BUG_ON((signed short)ref < 0); |
| 295 | np->grant_rx_ref[id] = ref; |
| 296 | |
| 297 | pfn = page_to_pfn(skb_shinfo(skb)->frags[0].page); |
| 298 | vaddr = page_address(skb_shinfo(skb)->frags[0].page); |
| 299 | |
| 300 | req = RING_GET_REQUEST(&np->rx, req_prod + i); |
| 301 | gnttab_grant_foreign_access_ref(ref, |
| 302 | np->xbdev->otherend_id, |
| 303 | pfn_to_mfn(pfn), |
| 304 | 0); |
| 305 | |
| 306 | req->id = id; |
| 307 | req->gref = ref; |
| 308 | } |
| 309 | |
| 310 | wmb(); /* barrier so backend seens requests */ |
| 311 | |
| 312 | /* Above is a suitable barrier to ensure backend will see requests. */ |
| 313 | np->rx.req_prod_pvt = req_prod + i; |
| 314 | push: |
| 315 | RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&np->rx, notify); |
| 316 | if (notify) |
| 317 | notify_remote_via_irq(np->netdev->irq); |
| 318 | } |
| 319 | |
| 320 | static int xennet_open(struct net_device *dev) |
| 321 | { |
| 322 | struct netfront_info *np = netdev_priv(dev); |
| 323 | |
| 324 | napi_enable(&np->napi); |
| 325 | |
| 326 | spin_lock_bh(&np->rx_lock); |
| 327 | if (netif_carrier_ok(dev)) { |
| 328 | xennet_alloc_rx_buffers(dev); |
| 329 | np->rx.sring->rsp_event = np->rx.rsp_cons + 1; |
| 330 | if (RING_HAS_UNCONSUMED_RESPONSES(&np->rx)) |
| 331 | napi_schedule(&np->napi); |
| 332 | } |
| 333 | spin_unlock_bh(&np->rx_lock); |
| 334 | |
| 335 | netif_start_queue(dev); |
| 336 | |
| 337 | return 0; |
| 338 | } |
| 339 | |
| 340 | static void xennet_tx_buf_gc(struct net_device *dev) |
| 341 | { |
| 342 | RING_IDX cons, prod; |
| 343 | unsigned short id; |
| 344 | struct netfront_info *np = netdev_priv(dev); |
| 345 | struct sk_buff *skb; |
| 346 | |
| 347 | BUG_ON(!netif_carrier_ok(dev)); |
| 348 | |
| 349 | do { |
| 350 | prod = np->tx.sring->rsp_prod; |
| 351 | rmb(); /* Ensure we see responses up to 'rp'. */ |
| 352 | |
| 353 | for (cons = np->tx.rsp_cons; cons != prod; cons++) { |
| 354 | struct xen_netif_tx_response *txrsp; |
| 355 | |
| 356 | txrsp = RING_GET_RESPONSE(&np->tx, cons); |
| 357 | if (txrsp->status == NETIF_RSP_NULL) |
| 358 | continue; |
| 359 | |
| 360 | id = txrsp->id; |
| 361 | skb = np->tx_skbs[id].skb; |
| 362 | if (unlikely(gnttab_query_foreign_access( |
| 363 | np->grant_tx_ref[id]) != 0)) { |
| 364 | printk(KERN_ALERT "xennet_tx_buf_gc: warning " |
| 365 | "-- grant still in use by backend " |
| 366 | "domain.\n"); |
| 367 | BUG(); |
| 368 | } |
| 369 | gnttab_end_foreign_access_ref( |
| 370 | np->grant_tx_ref[id], GNTMAP_readonly); |
| 371 | gnttab_release_grant_reference( |
| 372 | &np->gref_tx_head, np->grant_tx_ref[id]); |
| 373 | np->grant_tx_ref[id] = GRANT_INVALID_REF; |
| 374 | add_id_to_freelist(&np->tx_skb_freelist, np->tx_skbs, id); |
| 375 | dev_kfree_skb_irq(skb); |
| 376 | } |
| 377 | |
| 378 | np->tx.rsp_cons = prod; |
| 379 | |
| 380 | /* |
| 381 | * Set a new event, then check for race with update of tx_cons. |
| 382 | * Note that it is essential to schedule a callback, no matter |
| 383 | * how few buffers are pending. Even if there is space in the |
| 384 | * transmit ring, higher layers may be blocked because too much |
| 385 | * data is outstanding: in such cases notification from Xen is |
| 386 | * likely to be the only kick that we'll get. |
| 387 | */ |
| 388 | np->tx.sring->rsp_event = |
| 389 | prod + ((np->tx.sring->req_prod - prod) >> 1) + 1; |
| 390 | mb(); /* update shared area */ |
| 391 | } while ((cons == prod) && (prod != np->tx.sring->rsp_prod)); |
| 392 | |
| 393 | xennet_maybe_wake_tx(dev); |
| 394 | } |
| 395 | |
| 396 | static void xennet_make_frags(struct sk_buff *skb, struct net_device *dev, |
| 397 | struct xen_netif_tx_request *tx) |
| 398 | { |
| 399 | struct netfront_info *np = netdev_priv(dev); |
| 400 | char *data = skb->data; |
| 401 | unsigned long mfn; |
| 402 | RING_IDX prod = np->tx.req_prod_pvt; |
| 403 | int frags = skb_shinfo(skb)->nr_frags; |
| 404 | unsigned int offset = offset_in_page(data); |
| 405 | unsigned int len = skb_headlen(skb); |
| 406 | unsigned int id; |
| 407 | grant_ref_t ref; |
| 408 | int i; |
| 409 | |
| 410 | /* While the header overlaps a page boundary (including being |
| 411 | larger than a page), split it it into page-sized chunks. */ |
| 412 | while (len > PAGE_SIZE - offset) { |
| 413 | tx->size = PAGE_SIZE - offset; |
| 414 | tx->flags |= NETTXF_more_data; |
| 415 | len -= tx->size; |
| 416 | data += tx->size; |
| 417 | offset = 0; |
| 418 | |
| 419 | id = get_id_from_freelist(&np->tx_skb_freelist, np->tx_skbs); |
| 420 | np->tx_skbs[id].skb = skb_get(skb); |
| 421 | tx = RING_GET_REQUEST(&np->tx, prod++); |
| 422 | tx->id = id; |
| 423 | ref = gnttab_claim_grant_reference(&np->gref_tx_head); |
| 424 | BUG_ON((signed short)ref < 0); |
| 425 | |
| 426 | mfn = virt_to_mfn(data); |
| 427 | gnttab_grant_foreign_access_ref(ref, np->xbdev->otherend_id, |
| 428 | mfn, GNTMAP_readonly); |
| 429 | |
| 430 | tx->gref = np->grant_tx_ref[id] = ref; |
| 431 | tx->offset = offset; |
| 432 | tx->size = len; |
| 433 | tx->flags = 0; |
| 434 | } |
| 435 | |
| 436 | /* Grant backend access to each skb fragment page. */ |
| 437 | for (i = 0; i < frags; i++) { |
| 438 | skb_frag_t *frag = skb_shinfo(skb)->frags + i; |
| 439 | |
| 440 | tx->flags |= NETTXF_more_data; |
| 441 | |
| 442 | id = get_id_from_freelist(&np->tx_skb_freelist, np->tx_skbs); |
| 443 | np->tx_skbs[id].skb = skb_get(skb); |
| 444 | tx = RING_GET_REQUEST(&np->tx, prod++); |
| 445 | tx->id = id; |
| 446 | ref = gnttab_claim_grant_reference(&np->gref_tx_head); |
| 447 | BUG_ON((signed short)ref < 0); |
| 448 | |
| 449 | mfn = pfn_to_mfn(page_to_pfn(frag->page)); |
| 450 | gnttab_grant_foreign_access_ref(ref, np->xbdev->otherend_id, |
| 451 | mfn, GNTMAP_readonly); |
| 452 | |
| 453 | tx->gref = np->grant_tx_ref[id] = ref; |
| 454 | tx->offset = frag->page_offset; |
| 455 | tx->size = frag->size; |
| 456 | tx->flags = 0; |
| 457 | } |
| 458 | |
| 459 | np->tx.req_prod_pvt = prod; |
| 460 | } |
| 461 | |
| 462 | static int xennet_start_xmit(struct sk_buff *skb, struct net_device *dev) |
| 463 | { |
| 464 | unsigned short id; |
| 465 | struct netfront_info *np = netdev_priv(dev); |
| 466 | struct xen_netif_tx_request *tx; |
| 467 | struct xen_netif_extra_info *extra; |
| 468 | char *data = skb->data; |
| 469 | RING_IDX i; |
| 470 | grant_ref_t ref; |
| 471 | unsigned long mfn; |
| 472 | int notify; |
| 473 | int frags = skb_shinfo(skb)->nr_frags; |
| 474 | unsigned int offset = offset_in_page(data); |
| 475 | unsigned int len = skb_headlen(skb); |
| 476 | |
| 477 | frags += DIV_ROUND_UP(offset + len, PAGE_SIZE); |
| 478 | if (unlikely(frags > MAX_SKB_FRAGS + 1)) { |
| 479 | printk(KERN_ALERT "xennet: skb rides the rocket: %d frags\n", |
| 480 | frags); |
| 481 | dump_stack(); |
| 482 | goto drop; |
| 483 | } |
| 484 | |
| 485 | spin_lock_irq(&np->tx_lock); |
| 486 | |
| 487 | if (unlikely(!netif_carrier_ok(dev) || |
| 488 | (frags > 1 && !xennet_can_sg(dev)) || |
| 489 | netif_needs_gso(dev, skb))) { |
| 490 | spin_unlock_irq(&np->tx_lock); |
| 491 | goto drop; |
| 492 | } |
| 493 | |
| 494 | i = np->tx.req_prod_pvt; |
| 495 | |
| 496 | id = get_id_from_freelist(&np->tx_skb_freelist, np->tx_skbs); |
| 497 | np->tx_skbs[id].skb = skb; |
| 498 | |
| 499 | tx = RING_GET_REQUEST(&np->tx, i); |
| 500 | |
| 501 | tx->id = id; |
| 502 | ref = gnttab_claim_grant_reference(&np->gref_tx_head); |
| 503 | BUG_ON((signed short)ref < 0); |
| 504 | mfn = virt_to_mfn(data); |
| 505 | gnttab_grant_foreign_access_ref( |
| 506 | ref, np->xbdev->otherend_id, mfn, GNTMAP_readonly); |
| 507 | tx->gref = np->grant_tx_ref[id] = ref; |
| 508 | tx->offset = offset; |
| 509 | tx->size = len; |
| 510 | extra = NULL; |
| 511 | |
| 512 | tx->flags = 0; |
| 513 | if (skb->ip_summed == CHECKSUM_PARTIAL) |
| 514 | /* local packet? */ |
| 515 | tx->flags |= NETTXF_csum_blank | NETTXF_data_validated; |
| 516 | else if (skb->ip_summed == CHECKSUM_UNNECESSARY) |
| 517 | /* remote but checksummed. */ |
| 518 | tx->flags |= NETTXF_data_validated; |
| 519 | |
| 520 | if (skb_shinfo(skb)->gso_size) { |
| 521 | struct xen_netif_extra_info *gso; |
| 522 | |
| 523 | gso = (struct xen_netif_extra_info *) |
| 524 | RING_GET_REQUEST(&np->tx, ++i); |
| 525 | |
| 526 | if (extra) |
| 527 | extra->flags |= XEN_NETIF_EXTRA_FLAG_MORE; |
| 528 | else |
| 529 | tx->flags |= NETTXF_extra_info; |
| 530 | |
| 531 | gso->u.gso.size = skb_shinfo(skb)->gso_size; |
| 532 | gso->u.gso.type = XEN_NETIF_GSO_TYPE_TCPV4; |
| 533 | gso->u.gso.pad = 0; |
| 534 | gso->u.gso.features = 0; |
| 535 | |
| 536 | gso->type = XEN_NETIF_EXTRA_TYPE_GSO; |
| 537 | gso->flags = 0; |
| 538 | extra = gso; |
| 539 | } |
| 540 | |
| 541 | np->tx.req_prod_pvt = i + 1; |
| 542 | |
| 543 | xennet_make_frags(skb, dev, tx); |
| 544 | tx->size = skb->len; |
| 545 | |
| 546 | RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&np->tx, notify); |
| 547 | if (notify) |
| 548 | notify_remote_via_irq(np->netdev->irq); |
| 549 | |
| 550 | dev->stats.tx_bytes += skb->len; |
| 551 | dev->stats.tx_packets++; |
| 552 | |
| 553 | /* Note: It is not safe to access skb after xennet_tx_buf_gc()! */ |
| 554 | xennet_tx_buf_gc(dev); |
| 555 | |
| 556 | if (!netfront_tx_slot_available(np)) |
| 557 | netif_stop_queue(dev); |
| 558 | |
| 559 | spin_unlock_irq(&np->tx_lock); |
| 560 | |
| 561 | return NETDEV_TX_OK; |
| 562 | |
| 563 | drop: |
| 564 | dev->stats.tx_dropped++; |
| 565 | dev_kfree_skb(skb); |
| 566 | return NETDEV_TX_OK; |
| 567 | } |
| 568 | |
| 569 | static int xennet_close(struct net_device *dev) |
| 570 | { |
| 571 | struct netfront_info *np = netdev_priv(dev); |
| 572 | netif_stop_queue(np->netdev); |
| 573 | napi_disable(&np->napi); |
| 574 | return 0; |
| 575 | } |
| 576 | |
| 577 | static void xennet_move_rx_slot(struct netfront_info *np, struct sk_buff *skb, |
| 578 | grant_ref_t ref) |
| 579 | { |
| 580 | int new = xennet_rxidx(np->rx.req_prod_pvt); |
| 581 | |
| 582 | BUG_ON(np->rx_skbs[new]); |
| 583 | np->rx_skbs[new] = skb; |
| 584 | np->grant_rx_ref[new] = ref; |
| 585 | RING_GET_REQUEST(&np->rx, np->rx.req_prod_pvt)->id = new; |
| 586 | RING_GET_REQUEST(&np->rx, np->rx.req_prod_pvt)->gref = ref; |
| 587 | np->rx.req_prod_pvt++; |
| 588 | } |
| 589 | |
| 590 | static int xennet_get_extras(struct netfront_info *np, |
| 591 | struct xen_netif_extra_info *extras, |
| 592 | RING_IDX rp) |
| 593 | |
| 594 | { |
| 595 | struct xen_netif_extra_info *extra; |
| 596 | struct device *dev = &np->netdev->dev; |
| 597 | RING_IDX cons = np->rx.rsp_cons; |
| 598 | int err = 0; |
| 599 | |
| 600 | do { |
| 601 | struct sk_buff *skb; |
| 602 | grant_ref_t ref; |
| 603 | |
| 604 | if (unlikely(cons + 1 == rp)) { |
| 605 | if (net_ratelimit()) |
| 606 | dev_warn(dev, "Missing extra info\n"); |
| 607 | err = -EBADR; |
| 608 | break; |
| 609 | } |
| 610 | |
| 611 | extra = (struct xen_netif_extra_info *) |
| 612 | RING_GET_RESPONSE(&np->rx, ++cons); |
| 613 | |
| 614 | if (unlikely(!extra->type || |
| 615 | extra->type >= XEN_NETIF_EXTRA_TYPE_MAX)) { |
| 616 | if (net_ratelimit()) |
| 617 | dev_warn(dev, "Invalid extra type: %d\n", |
| 618 | extra->type); |
| 619 | err = -EINVAL; |
| 620 | } else { |
| 621 | memcpy(&extras[extra->type - 1], extra, |
| 622 | sizeof(*extra)); |
| 623 | } |
| 624 | |
| 625 | skb = xennet_get_rx_skb(np, cons); |
| 626 | ref = xennet_get_rx_ref(np, cons); |
| 627 | xennet_move_rx_slot(np, skb, ref); |
| 628 | } while (extra->flags & XEN_NETIF_EXTRA_FLAG_MORE); |
| 629 | |
| 630 | np->rx.rsp_cons = cons; |
| 631 | return err; |
| 632 | } |
| 633 | |
| 634 | static int xennet_get_responses(struct netfront_info *np, |
| 635 | struct netfront_rx_info *rinfo, RING_IDX rp, |
| 636 | struct sk_buff_head *list) |
| 637 | { |
| 638 | struct xen_netif_rx_response *rx = &rinfo->rx; |
| 639 | struct xen_netif_extra_info *extras = rinfo->extras; |
| 640 | struct device *dev = &np->netdev->dev; |
| 641 | RING_IDX cons = np->rx.rsp_cons; |
| 642 | struct sk_buff *skb = xennet_get_rx_skb(np, cons); |
| 643 | grant_ref_t ref = xennet_get_rx_ref(np, cons); |
| 644 | int max = MAX_SKB_FRAGS + (rx->status <= RX_COPY_THRESHOLD); |
| 645 | int frags = 1; |
| 646 | int err = 0; |
| 647 | unsigned long ret; |
| 648 | |
| 649 | if (rx->flags & NETRXF_extra_info) { |
| 650 | err = xennet_get_extras(np, extras, rp); |
| 651 | cons = np->rx.rsp_cons; |
| 652 | } |
| 653 | |
| 654 | for (;;) { |
| 655 | if (unlikely(rx->status < 0 || |
| 656 | rx->offset + rx->status > PAGE_SIZE)) { |
| 657 | if (net_ratelimit()) |
| 658 | dev_warn(dev, "rx->offset: %x, size: %u\n", |
| 659 | rx->offset, rx->status); |
| 660 | xennet_move_rx_slot(np, skb, ref); |
| 661 | err = -EINVAL; |
| 662 | goto next; |
| 663 | } |
| 664 | |
| 665 | /* |
| 666 | * This definitely indicates a bug, either in this driver or in |
| 667 | * the backend driver. In future this should flag the bad |
| 668 | * situation to the system controller to reboot the backed. |
| 669 | */ |
| 670 | if (ref == GRANT_INVALID_REF) { |
| 671 | if (net_ratelimit()) |
| 672 | dev_warn(dev, "Bad rx response id %d.\n", |
| 673 | rx->id); |
| 674 | err = -EINVAL; |
| 675 | goto next; |
| 676 | } |
| 677 | |
| 678 | ret = gnttab_end_foreign_access_ref(ref, 0); |
| 679 | BUG_ON(!ret); |
| 680 | |
| 681 | gnttab_release_grant_reference(&np->gref_rx_head, ref); |
| 682 | |
| 683 | __skb_queue_tail(list, skb); |
| 684 | |
| 685 | next: |
| 686 | if (!(rx->flags & NETRXF_more_data)) |
| 687 | break; |
| 688 | |
| 689 | if (cons + frags == rp) { |
| 690 | if (net_ratelimit()) |
| 691 | dev_warn(dev, "Need more frags\n"); |
| 692 | err = -ENOENT; |
| 693 | break; |
| 694 | } |
| 695 | |
| 696 | rx = RING_GET_RESPONSE(&np->rx, cons + frags); |
| 697 | skb = xennet_get_rx_skb(np, cons + frags); |
| 698 | ref = xennet_get_rx_ref(np, cons + frags); |
| 699 | frags++; |
| 700 | } |
| 701 | |
| 702 | if (unlikely(frags > max)) { |
| 703 | if (net_ratelimit()) |
| 704 | dev_warn(dev, "Too many frags\n"); |
| 705 | err = -E2BIG; |
| 706 | } |
| 707 | |
| 708 | if (unlikely(err)) |
| 709 | np->rx.rsp_cons = cons + frags; |
| 710 | |
| 711 | return err; |
| 712 | } |
| 713 | |
| 714 | static int xennet_set_skb_gso(struct sk_buff *skb, |
| 715 | struct xen_netif_extra_info *gso) |
| 716 | { |
| 717 | if (!gso->u.gso.size) { |
| 718 | if (net_ratelimit()) |
| 719 | printk(KERN_WARNING "GSO size must not be zero.\n"); |
| 720 | return -EINVAL; |
| 721 | } |
| 722 | |
| 723 | /* Currently only TCPv4 S.O. is supported. */ |
| 724 | if (gso->u.gso.type != XEN_NETIF_GSO_TYPE_TCPV4) { |
| 725 | if (net_ratelimit()) |
| 726 | printk(KERN_WARNING "Bad GSO type %d.\n", gso->u.gso.type); |
| 727 | return -EINVAL; |
| 728 | } |
| 729 | |
| 730 | skb_shinfo(skb)->gso_size = gso->u.gso.size; |
| 731 | skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4; |
| 732 | |
| 733 | /* Header must be checked, and gso_segs computed. */ |
| 734 | skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; |
| 735 | skb_shinfo(skb)->gso_segs = 0; |
| 736 | |
| 737 | return 0; |
| 738 | } |
| 739 | |
| 740 | static RING_IDX xennet_fill_frags(struct netfront_info *np, |
| 741 | struct sk_buff *skb, |
| 742 | struct sk_buff_head *list) |
| 743 | { |
| 744 | struct skb_shared_info *shinfo = skb_shinfo(skb); |
| 745 | int nr_frags = shinfo->nr_frags; |
| 746 | RING_IDX cons = np->rx.rsp_cons; |
| 747 | skb_frag_t *frag = shinfo->frags + nr_frags; |
| 748 | struct sk_buff *nskb; |
| 749 | |
| 750 | while ((nskb = __skb_dequeue(list))) { |
| 751 | struct xen_netif_rx_response *rx = |
| 752 | RING_GET_RESPONSE(&np->rx, ++cons); |
| 753 | |
| 754 | frag->page = skb_shinfo(nskb)->frags[0].page; |
| 755 | frag->page_offset = rx->offset; |
| 756 | frag->size = rx->status; |
| 757 | |
| 758 | skb->data_len += rx->status; |
| 759 | |
| 760 | skb_shinfo(nskb)->nr_frags = 0; |
| 761 | kfree_skb(nskb); |
| 762 | |
| 763 | frag++; |
| 764 | nr_frags++; |
| 765 | } |
| 766 | |
| 767 | shinfo->nr_frags = nr_frags; |
| 768 | return cons; |
| 769 | } |
| 770 | |
| 771 | static int skb_checksum_setup(struct sk_buff *skb) |
| 772 | { |
| 773 | struct iphdr *iph; |
| 774 | unsigned char *th; |
| 775 | int err = -EPROTO; |
| 776 | |
| 777 | if (skb->protocol != htons(ETH_P_IP)) |
| 778 | goto out; |
| 779 | |
| 780 | iph = (void *)skb->data; |
| 781 | th = skb->data + 4 * iph->ihl; |
| 782 | if (th >= skb_tail_pointer(skb)) |
| 783 | goto out; |
| 784 | |
| 785 | skb->csum_start = th - skb->head; |
| 786 | switch (iph->protocol) { |
| 787 | case IPPROTO_TCP: |
| 788 | skb->csum_offset = offsetof(struct tcphdr, check); |
| 789 | break; |
| 790 | case IPPROTO_UDP: |
| 791 | skb->csum_offset = offsetof(struct udphdr, check); |
| 792 | break; |
| 793 | default: |
| 794 | if (net_ratelimit()) |
| 795 | printk(KERN_ERR "Attempting to checksum a non-" |
| 796 | "TCP/UDP packet, dropping a protocol" |
| 797 | " %d packet", iph->protocol); |
| 798 | goto out; |
| 799 | } |
| 800 | |
| 801 | if ((th + skb->csum_offset + 2) > skb_tail_pointer(skb)) |
| 802 | goto out; |
| 803 | |
| 804 | err = 0; |
| 805 | |
| 806 | out: |
| 807 | return err; |
| 808 | } |
| 809 | |
| 810 | static int handle_incoming_queue(struct net_device *dev, |
| 811 | struct sk_buff_head *rxq) |
| 812 | { |
| 813 | int packets_dropped = 0; |
| 814 | struct sk_buff *skb; |
| 815 | |
| 816 | while ((skb = __skb_dequeue(rxq)) != NULL) { |
| 817 | struct page *page = NETFRONT_SKB_CB(skb)->page; |
| 818 | void *vaddr = page_address(page); |
| 819 | unsigned offset = NETFRONT_SKB_CB(skb)->offset; |
| 820 | |
| 821 | memcpy(skb->data, vaddr + offset, |
| 822 | skb_headlen(skb)); |
| 823 | |
| 824 | if (page != skb_shinfo(skb)->frags[0].page) |
| 825 | __free_page(page); |
| 826 | |
| 827 | /* Ethernet work: Delayed to here as it peeks the header. */ |
| 828 | skb->protocol = eth_type_trans(skb, dev); |
| 829 | |
| 830 | if (skb->ip_summed == CHECKSUM_PARTIAL) { |
| 831 | if (skb_checksum_setup(skb)) { |
| 832 | kfree_skb(skb); |
| 833 | packets_dropped++; |
| 834 | dev->stats.rx_errors++; |
| 835 | continue; |
| 836 | } |
| 837 | } |
| 838 | |
| 839 | dev->stats.rx_packets++; |
| 840 | dev->stats.rx_bytes += skb->len; |
| 841 | |
| 842 | /* Pass it up. */ |
| 843 | netif_receive_skb(skb); |
| 844 | } |
| 845 | |
| 846 | return packets_dropped; |
| 847 | } |
| 848 | |
| 849 | static int xennet_poll(struct napi_struct *napi, int budget) |
| 850 | { |
| 851 | struct netfront_info *np = container_of(napi, struct netfront_info, napi); |
| 852 | struct net_device *dev = np->netdev; |
| 853 | struct sk_buff *skb; |
| 854 | struct netfront_rx_info rinfo; |
| 855 | struct xen_netif_rx_response *rx = &rinfo.rx; |
| 856 | struct xen_netif_extra_info *extras = rinfo.extras; |
| 857 | RING_IDX i, rp; |
| 858 | int work_done; |
| 859 | struct sk_buff_head rxq; |
| 860 | struct sk_buff_head errq; |
| 861 | struct sk_buff_head tmpq; |
| 862 | unsigned long flags; |
| 863 | unsigned int len; |
| 864 | int err; |
| 865 | |
| 866 | spin_lock(&np->rx_lock); |
| 867 | |
| 868 | skb_queue_head_init(&rxq); |
| 869 | skb_queue_head_init(&errq); |
| 870 | skb_queue_head_init(&tmpq); |
| 871 | |
| 872 | rp = np->rx.sring->rsp_prod; |
| 873 | rmb(); /* Ensure we see queued responses up to 'rp'. */ |
| 874 | |
| 875 | i = np->rx.rsp_cons; |
| 876 | work_done = 0; |
| 877 | while ((i != rp) && (work_done < budget)) { |
| 878 | memcpy(rx, RING_GET_RESPONSE(&np->rx, i), sizeof(*rx)); |
| 879 | memset(extras, 0, sizeof(rinfo.extras)); |
| 880 | |
| 881 | err = xennet_get_responses(np, &rinfo, rp, &tmpq); |
| 882 | |
| 883 | if (unlikely(err)) { |
| 884 | err: |
| 885 | while ((skb = __skb_dequeue(&tmpq))) |
| 886 | __skb_queue_tail(&errq, skb); |
| 887 | dev->stats.rx_errors++; |
| 888 | i = np->rx.rsp_cons; |
| 889 | continue; |
| 890 | } |
| 891 | |
| 892 | skb = __skb_dequeue(&tmpq); |
| 893 | |
| 894 | if (extras[XEN_NETIF_EXTRA_TYPE_GSO - 1].type) { |
| 895 | struct xen_netif_extra_info *gso; |
| 896 | gso = &extras[XEN_NETIF_EXTRA_TYPE_GSO - 1]; |
| 897 | |
| 898 | if (unlikely(xennet_set_skb_gso(skb, gso))) { |
| 899 | __skb_queue_head(&tmpq, skb); |
| 900 | np->rx.rsp_cons += skb_queue_len(&tmpq); |
| 901 | goto err; |
| 902 | } |
| 903 | } |
| 904 | |
| 905 | NETFRONT_SKB_CB(skb)->page = skb_shinfo(skb)->frags[0].page; |
| 906 | NETFRONT_SKB_CB(skb)->offset = rx->offset; |
| 907 | |
| 908 | len = rx->status; |
| 909 | if (len > RX_COPY_THRESHOLD) |
| 910 | len = RX_COPY_THRESHOLD; |
| 911 | skb_put(skb, len); |
| 912 | |
| 913 | if (rx->status > len) { |
| 914 | skb_shinfo(skb)->frags[0].page_offset = |
| 915 | rx->offset + len; |
| 916 | skb_shinfo(skb)->frags[0].size = rx->status - len; |
| 917 | skb->data_len = rx->status - len; |
| 918 | } else { |
| 919 | skb_shinfo(skb)->frags[0].page = NULL; |
| 920 | skb_shinfo(skb)->nr_frags = 0; |
| 921 | } |
| 922 | |
| 923 | i = xennet_fill_frags(np, skb, &tmpq); |
| 924 | |
| 925 | /* |
| 926 | * Truesize approximates the size of true data plus |
| 927 | * any supervisor overheads. Adding hypervisor |
| 928 | * overheads has been shown to significantly reduce |
| 929 | * achievable bandwidth with the default receive |
| 930 | * buffer size. It is therefore not wise to account |
| 931 | * for it here. |
| 932 | * |
| 933 | * After alloc_skb(RX_COPY_THRESHOLD), truesize is set |
| 934 | * to RX_COPY_THRESHOLD + the supervisor |
| 935 | * overheads. Here, we add the size of the data pulled |
| 936 | * in xennet_fill_frags(). |
| 937 | * |
| 938 | * We also adjust for any unused space in the main |
| 939 | * data area by subtracting (RX_COPY_THRESHOLD - |
| 940 | * len). This is especially important with drivers |
| 941 | * which split incoming packets into header and data, |
| 942 | * using only 66 bytes of the main data area (see the |
| 943 | * e1000 driver for example.) On such systems, |
| 944 | * without this last adjustement, our achievable |
| 945 | * receive throughout using the standard receive |
| 946 | * buffer size was cut by 25%(!!!). |
| 947 | */ |
| 948 | skb->truesize += skb->data_len - (RX_COPY_THRESHOLD - len); |
| 949 | skb->len += skb->data_len; |
| 950 | |
| 951 | if (rx->flags & NETRXF_csum_blank) |
| 952 | skb->ip_summed = CHECKSUM_PARTIAL; |
| 953 | else if (rx->flags & NETRXF_data_validated) |
| 954 | skb->ip_summed = CHECKSUM_UNNECESSARY; |
| 955 | |
| 956 | __skb_queue_tail(&rxq, skb); |
| 957 | |
| 958 | np->rx.rsp_cons = ++i; |
| 959 | work_done++; |
| 960 | } |
| 961 | |
| 962 | __skb_queue_purge(&errq); |
| 963 | |
| 964 | work_done -= handle_incoming_queue(dev, &rxq); |
| 965 | |
| 966 | /* If we get a callback with very few responses, reduce fill target. */ |
| 967 | /* NB. Note exponential increase, linear decrease. */ |
| 968 | if (((np->rx.req_prod_pvt - np->rx.sring->rsp_prod) > |
| 969 | ((3*np->rx_target) / 4)) && |
| 970 | (--np->rx_target < np->rx_min_target)) |
| 971 | np->rx_target = np->rx_min_target; |
| 972 | |
| 973 | xennet_alloc_rx_buffers(dev); |
| 974 | |
| 975 | if (work_done < budget) { |
| 976 | int more_to_do = 0; |
| 977 | |
| 978 | local_irq_save(flags); |
| 979 | |
| 980 | RING_FINAL_CHECK_FOR_RESPONSES(&np->rx, more_to_do); |
| 981 | if (!more_to_do) |
| 982 | __napi_complete(napi); |
| 983 | |
| 984 | local_irq_restore(flags); |
| 985 | } |
| 986 | |
| 987 | spin_unlock(&np->rx_lock); |
| 988 | |
| 989 | return work_done; |
| 990 | } |
| 991 | |
| 992 | static int xennet_change_mtu(struct net_device *dev, int mtu) |
| 993 | { |
| 994 | int max = xennet_can_sg(dev) ? 65535 - ETH_HLEN : ETH_DATA_LEN; |
| 995 | |
| 996 | if (mtu > max) |
| 997 | return -EINVAL; |
| 998 | dev->mtu = mtu; |
| 999 | return 0; |
| 1000 | } |
| 1001 | |
| 1002 | static void xennet_release_tx_bufs(struct netfront_info *np) |
| 1003 | { |
| 1004 | struct sk_buff *skb; |
| 1005 | int i; |
| 1006 | |
| 1007 | for (i = 0; i < NET_TX_RING_SIZE; i++) { |
| 1008 | /* Skip over entries which are actually freelist references */ |
| 1009 | if (skb_entry_is_link(&np->tx_skbs[i])) |
| 1010 | continue; |
| 1011 | |
| 1012 | skb = np->tx_skbs[i].skb; |
| 1013 | gnttab_end_foreign_access_ref(np->grant_tx_ref[i], |
| 1014 | GNTMAP_readonly); |
| 1015 | gnttab_release_grant_reference(&np->gref_tx_head, |
| 1016 | np->grant_tx_ref[i]); |
| 1017 | np->grant_tx_ref[i] = GRANT_INVALID_REF; |
| 1018 | add_id_to_freelist(&np->tx_skb_freelist, np->tx_skbs, i); |
| 1019 | dev_kfree_skb_irq(skb); |
| 1020 | } |
| 1021 | } |
| 1022 | |
| 1023 | static void xennet_release_rx_bufs(struct netfront_info *np) |
| 1024 | { |
| 1025 | struct mmu_update *mmu = np->rx_mmu; |
| 1026 | struct multicall_entry *mcl = np->rx_mcl; |
| 1027 | struct sk_buff_head free_list; |
| 1028 | struct sk_buff *skb; |
| 1029 | unsigned long mfn; |
| 1030 | int xfer = 0, noxfer = 0, unused = 0; |
| 1031 | int id, ref; |
| 1032 | |
| 1033 | dev_warn(&np->netdev->dev, "%s: fix me for copying receiver.\n", |
| 1034 | __func__); |
| 1035 | return; |
| 1036 | |
| 1037 | skb_queue_head_init(&free_list); |
| 1038 | |
| 1039 | spin_lock_bh(&np->rx_lock); |
| 1040 | |
| 1041 | for (id = 0; id < NET_RX_RING_SIZE; id++) { |
| 1042 | ref = np->grant_rx_ref[id]; |
| 1043 | if (ref == GRANT_INVALID_REF) { |
| 1044 | unused++; |
| 1045 | continue; |
| 1046 | } |
| 1047 | |
| 1048 | skb = np->rx_skbs[id]; |
| 1049 | mfn = gnttab_end_foreign_transfer_ref(ref); |
| 1050 | gnttab_release_grant_reference(&np->gref_rx_head, ref); |
| 1051 | np->grant_rx_ref[id] = GRANT_INVALID_REF; |
| 1052 | |
| 1053 | if (0 == mfn) { |
| 1054 | skb_shinfo(skb)->nr_frags = 0; |
| 1055 | dev_kfree_skb(skb); |
| 1056 | noxfer++; |
| 1057 | continue; |
| 1058 | } |
| 1059 | |
| 1060 | if (!xen_feature(XENFEAT_auto_translated_physmap)) { |
| 1061 | /* Remap the page. */ |
| 1062 | struct page *page = skb_shinfo(skb)->frags[0].page; |
| 1063 | unsigned long pfn = page_to_pfn(page); |
| 1064 | void *vaddr = page_address(page); |
| 1065 | |
| 1066 | MULTI_update_va_mapping(mcl, (unsigned long)vaddr, |
| 1067 | mfn_pte(mfn, PAGE_KERNEL), |
| 1068 | 0); |
| 1069 | mcl++; |
| 1070 | mmu->ptr = ((u64)mfn << PAGE_SHIFT) |
| 1071 | | MMU_MACHPHYS_UPDATE; |
| 1072 | mmu->val = pfn; |
| 1073 | mmu++; |
| 1074 | |
| 1075 | set_phys_to_machine(pfn, mfn); |
| 1076 | } |
| 1077 | __skb_queue_tail(&free_list, skb); |
| 1078 | xfer++; |
| 1079 | } |
| 1080 | |
| 1081 | dev_info(&np->netdev->dev, "%s: %d xfer, %d noxfer, %d unused\n", |
| 1082 | __func__, xfer, noxfer, unused); |
| 1083 | |
| 1084 | if (xfer) { |
| 1085 | if (!xen_feature(XENFEAT_auto_translated_physmap)) { |
| 1086 | /* Do all the remapping work and M2P updates. */ |
| 1087 | MULTI_mmu_update(mcl, np->rx_mmu, mmu - np->rx_mmu, |
| 1088 | NULL, DOMID_SELF); |
| 1089 | mcl++; |
| 1090 | HYPERVISOR_multicall(np->rx_mcl, mcl - np->rx_mcl); |
| 1091 | } |
| 1092 | } |
| 1093 | |
| 1094 | __skb_queue_purge(&free_list); |
| 1095 | |
| 1096 | spin_unlock_bh(&np->rx_lock); |
| 1097 | } |
| 1098 | |
| 1099 | static void xennet_uninit(struct net_device *dev) |
| 1100 | { |
| 1101 | struct netfront_info *np = netdev_priv(dev); |
| 1102 | xennet_release_tx_bufs(np); |
| 1103 | xennet_release_rx_bufs(np); |
| 1104 | gnttab_free_grant_references(np->gref_tx_head); |
| 1105 | gnttab_free_grant_references(np->gref_rx_head); |
| 1106 | } |
| 1107 | |
| 1108 | static const struct net_device_ops xennet_netdev_ops = { |
| 1109 | .ndo_open = xennet_open, |
| 1110 | .ndo_uninit = xennet_uninit, |
| 1111 | .ndo_stop = xennet_close, |
| 1112 | .ndo_start_xmit = xennet_start_xmit, |
| 1113 | .ndo_change_mtu = xennet_change_mtu, |
| 1114 | .ndo_set_mac_address = eth_mac_addr, |
| 1115 | .ndo_validate_addr = eth_validate_addr, |
| 1116 | }; |
| 1117 | |
| 1118 | static struct net_device * __devinit xennet_create_dev(struct xenbus_device *dev) |
| 1119 | { |
| 1120 | int i, err; |
| 1121 | struct net_device *netdev; |
| 1122 | struct netfront_info *np; |
| 1123 | |
| 1124 | netdev = alloc_etherdev(sizeof(struct netfront_info)); |
| 1125 | if (!netdev) { |
| 1126 | printk(KERN_WARNING "%s> alloc_etherdev failed.\n", |
| 1127 | __func__); |
| 1128 | return ERR_PTR(-ENOMEM); |
| 1129 | } |
| 1130 | |
| 1131 | np = netdev_priv(netdev); |
| 1132 | np->xbdev = dev; |
| 1133 | |
| 1134 | spin_lock_init(&np->tx_lock); |
| 1135 | spin_lock_init(&np->rx_lock); |
| 1136 | |
| 1137 | skb_queue_head_init(&np->rx_batch); |
| 1138 | np->rx_target = RX_DFL_MIN_TARGET; |
| 1139 | np->rx_min_target = RX_DFL_MIN_TARGET; |
| 1140 | np->rx_max_target = RX_MAX_TARGET; |
| 1141 | |
| 1142 | init_timer(&np->rx_refill_timer); |
| 1143 | np->rx_refill_timer.data = (unsigned long)netdev; |
| 1144 | np->rx_refill_timer.function = rx_refill_timeout; |
| 1145 | |
| 1146 | /* Initialise tx_skbs as a free chain containing every entry. */ |
| 1147 | np->tx_skb_freelist = 0; |
| 1148 | for (i = 0; i < NET_TX_RING_SIZE; i++) { |
| 1149 | skb_entry_set_link(&np->tx_skbs[i], i+1); |
| 1150 | np->grant_tx_ref[i] = GRANT_INVALID_REF; |
| 1151 | } |
| 1152 | |
| 1153 | /* Clear out rx_skbs */ |
| 1154 | for (i = 0; i < NET_RX_RING_SIZE; i++) { |
| 1155 | np->rx_skbs[i] = NULL; |
| 1156 | np->grant_rx_ref[i] = GRANT_INVALID_REF; |
| 1157 | } |
| 1158 | |
| 1159 | /* A grant for every tx ring slot */ |
| 1160 | if (gnttab_alloc_grant_references(TX_MAX_TARGET, |
| 1161 | &np->gref_tx_head) < 0) { |
| 1162 | printk(KERN_ALERT "#### netfront can't alloc tx grant refs\n"); |
| 1163 | err = -ENOMEM; |
| 1164 | goto exit; |
| 1165 | } |
| 1166 | /* A grant for every rx ring slot */ |
| 1167 | if (gnttab_alloc_grant_references(RX_MAX_TARGET, |
| 1168 | &np->gref_rx_head) < 0) { |
| 1169 | printk(KERN_ALERT "#### netfront can't alloc rx grant refs\n"); |
| 1170 | err = -ENOMEM; |
| 1171 | goto exit_free_tx; |
| 1172 | } |
| 1173 | |
| 1174 | netdev->netdev_ops = &xennet_netdev_ops; |
| 1175 | |
| 1176 | netif_napi_add(netdev, &np->napi, xennet_poll, 64); |
| 1177 | netdev->features = NETIF_F_IP_CSUM; |
| 1178 | |
| 1179 | SET_ETHTOOL_OPS(netdev, &xennet_ethtool_ops); |
| 1180 | SET_NETDEV_DEV(netdev, &dev->dev); |
| 1181 | |
| 1182 | np->netdev = netdev; |
| 1183 | |
| 1184 | netif_carrier_off(netdev); |
| 1185 | |
| 1186 | return netdev; |
| 1187 | |
| 1188 | exit_free_tx: |
| 1189 | gnttab_free_grant_references(np->gref_tx_head); |
| 1190 | exit: |
| 1191 | free_netdev(netdev); |
| 1192 | return ERR_PTR(err); |
| 1193 | } |
| 1194 | |
| 1195 | /** |
| 1196 | * Entry point to this code when a new device is created. Allocate the basic |
| 1197 | * structures and the ring buffers for communication with the backend, and |
| 1198 | * inform the backend of the appropriate details for those. |
| 1199 | */ |
| 1200 | static int __devinit netfront_probe(struct xenbus_device *dev, |
| 1201 | const struct xenbus_device_id *id) |
| 1202 | { |
| 1203 | int err; |
| 1204 | struct net_device *netdev; |
| 1205 | struct netfront_info *info; |
| 1206 | |
| 1207 | netdev = xennet_create_dev(dev); |
| 1208 | if (IS_ERR(netdev)) { |
| 1209 | err = PTR_ERR(netdev); |
| 1210 | xenbus_dev_fatal(dev, err, "creating netdev"); |
| 1211 | return err; |
| 1212 | } |
| 1213 | |
| 1214 | info = netdev_priv(netdev); |
| 1215 | dev_set_drvdata(&dev->dev, info); |
| 1216 | |
| 1217 | err = register_netdev(info->netdev); |
| 1218 | if (err) { |
| 1219 | printk(KERN_WARNING "%s: register_netdev err=%d\n", |
| 1220 | __func__, err); |
| 1221 | goto fail; |
| 1222 | } |
| 1223 | |
| 1224 | err = xennet_sysfs_addif(info->netdev); |
| 1225 | if (err) { |
| 1226 | unregister_netdev(info->netdev); |
| 1227 | printk(KERN_WARNING "%s: add sysfs failed err=%d\n", |
| 1228 | __func__, err); |
| 1229 | goto fail; |
| 1230 | } |
| 1231 | |
| 1232 | return 0; |
| 1233 | |
| 1234 | fail: |
| 1235 | free_netdev(netdev); |
| 1236 | dev_set_drvdata(&dev->dev, NULL); |
| 1237 | return err; |
| 1238 | } |
| 1239 | |
| 1240 | static void xennet_end_access(int ref, void *page) |
| 1241 | { |
| 1242 | /* This frees the page as a side-effect */ |
| 1243 | if (ref != GRANT_INVALID_REF) |
| 1244 | gnttab_end_foreign_access(ref, 0, (unsigned long)page); |
| 1245 | } |
| 1246 | |
| 1247 | static void xennet_disconnect_backend(struct netfront_info *info) |
| 1248 | { |
| 1249 | /* Stop old i/f to prevent errors whilst we rebuild the state. */ |
| 1250 | spin_lock_bh(&info->rx_lock); |
| 1251 | spin_lock_irq(&info->tx_lock); |
| 1252 | netif_carrier_off(info->netdev); |
| 1253 | spin_unlock_irq(&info->tx_lock); |
| 1254 | spin_unlock_bh(&info->rx_lock); |
| 1255 | |
| 1256 | if (info->netdev->irq) |
| 1257 | unbind_from_irqhandler(info->netdev->irq, info->netdev); |
| 1258 | info->evtchn = info->netdev->irq = 0; |
| 1259 | |
| 1260 | /* End access and free the pages */ |
| 1261 | xennet_end_access(info->tx_ring_ref, info->tx.sring); |
| 1262 | xennet_end_access(info->rx_ring_ref, info->rx.sring); |
| 1263 | |
| 1264 | info->tx_ring_ref = GRANT_INVALID_REF; |
| 1265 | info->rx_ring_ref = GRANT_INVALID_REF; |
| 1266 | info->tx.sring = NULL; |
| 1267 | info->rx.sring = NULL; |
| 1268 | } |
| 1269 | |
| 1270 | /** |
| 1271 | * We are reconnecting to the backend, due to a suspend/resume, or a backend |
| 1272 | * driver restart. We tear down our netif structure and recreate it, but |
| 1273 | * leave the device-layer structures intact so that this is transparent to the |
| 1274 | * rest of the kernel. |
| 1275 | */ |
| 1276 | static int netfront_resume(struct xenbus_device *dev) |
| 1277 | { |
| 1278 | struct netfront_info *info = dev_get_drvdata(&dev->dev); |
| 1279 | |
| 1280 | dev_dbg(&dev->dev, "%s\n", dev->nodename); |
| 1281 | |
| 1282 | xennet_disconnect_backend(info); |
| 1283 | return 0; |
| 1284 | } |
| 1285 | |
| 1286 | static int xen_net_read_mac(struct xenbus_device *dev, u8 mac[]) |
| 1287 | { |
| 1288 | char *s, *e, *macstr; |
| 1289 | int i; |
| 1290 | |
| 1291 | macstr = s = xenbus_read(XBT_NIL, dev->nodename, "mac", NULL); |
| 1292 | if (IS_ERR(macstr)) |
| 1293 | return PTR_ERR(macstr); |
| 1294 | |
| 1295 | for (i = 0; i < ETH_ALEN; i++) { |
| 1296 | mac[i] = simple_strtoul(s, &e, 16); |
| 1297 | if ((s == e) || (*e != ((i == ETH_ALEN-1) ? '\0' : ':'))) { |
| 1298 | kfree(macstr); |
| 1299 | return -ENOENT; |
| 1300 | } |
| 1301 | s = e+1; |
| 1302 | } |
| 1303 | |
| 1304 | kfree(macstr); |
| 1305 | return 0; |
| 1306 | } |
| 1307 | |
| 1308 | static irqreturn_t xennet_interrupt(int irq, void *dev_id) |
| 1309 | { |
| 1310 | struct net_device *dev = dev_id; |
| 1311 | struct netfront_info *np = netdev_priv(dev); |
| 1312 | unsigned long flags; |
| 1313 | |
| 1314 | spin_lock_irqsave(&np->tx_lock, flags); |
| 1315 | |
| 1316 | if (likely(netif_carrier_ok(dev))) { |
| 1317 | xennet_tx_buf_gc(dev); |
| 1318 | /* Under tx_lock: protects access to rx shared-ring indexes. */ |
| 1319 | if (RING_HAS_UNCONSUMED_RESPONSES(&np->rx)) |
| 1320 | napi_schedule(&np->napi); |
| 1321 | } |
| 1322 | |
| 1323 | spin_unlock_irqrestore(&np->tx_lock, flags); |
| 1324 | |
| 1325 | return IRQ_HANDLED; |
| 1326 | } |
| 1327 | |
| 1328 | static int setup_netfront(struct xenbus_device *dev, struct netfront_info *info) |
| 1329 | { |
| 1330 | struct xen_netif_tx_sring *txs; |
| 1331 | struct xen_netif_rx_sring *rxs; |
| 1332 | int err; |
| 1333 | struct net_device *netdev = info->netdev; |
| 1334 | |
| 1335 | info->tx_ring_ref = GRANT_INVALID_REF; |
| 1336 | info->rx_ring_ref = GRANT_INVALID_REF; |
| 1337 | info->rx.sring = NULL; |
| 1338 | info->tx.sring = NULL; |
| 1339 | netdev->irq = 0; |
| 1340 | |
| 1341 | err = xen_net_read_mac(dev, netdev->dev_addr); |
| 1342 | if (err) { |
| 1343 | xenbus_dev_fatal(dev, err, "parsing %s/mac", dev->nodename); |
| 1344 | goto fail; |
| 1345 | } |
| 1346 | |
| 1347 | txs = (struct xen_netif_tx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH); |
| 1348 | if (!txs) { |
| 1349 | err = -ENOMEM; |
| 1350 | xenbus_dev_fatal(dev, err, "allocating tx ring page"); |
| 1351 | goto fail; |
| 1352 | } |
| 1353 | SHARED_RING_INIT(txs); |
| 1354 | FRONT_RING_INIT(&info->tx, txs, PAGE_SIZE); |
| 1355 | |
| 1356 | err = xenbus_grant_ring(dev, virt_to_mfn(txs)); |
| 1357 | if (err < 0) { |
| 1358 | free_page((unsigned long)txs); |
| 1359 | goto fail; |
| 1360 | } |
| 1361 | |
| 1362 | info->tx_ring_ref = err; |
| 1363 | rxs = (struct xen_netif_rx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH); |
| 1364 | if (!rxs) { |
| 1365 | err = -ENOMEM; |
| 1366 | xenbus_dev_fatal(dev, err, "allocating rx ring page"); |
| 1367 | goto fail; |
| 1368 | } |
| 1369 | SHARED_RING_INIT(rxs); |
| 1370 | FRONT_RING_INIT(&info->rx, rxs, PAGE_SIZE); |
| 1371 | |
| 1372 | err = xenbus_grant_ring(dev, virt_to_mfn(rxs)); |
| 1373 | if (err < 0) { |
| 1374 | free_page((unsigned long)rxs); |
| 1375 | goto fail; |
| 1376 | } |
| 1377 | info->rx_ring_ref = err; |
| 1378 | |
| 1379 | err = xenbus_alloc_evtchn(dev, &info->evtchn); |
| 1380 | if (err) |
| 1381 | goto fail; |
| 1382 | |
| 1383 | err = bind_evtchn_to_irqhandler(info->evtchn, xennet_interrupt, |
| 1384 | IRQF_SAMPLE_RANDOM, netdev->name, |
| 1385 | netdev); |
| 1386 | if (err < 0) |
| 1387 | goto fail; |
| 1388 | netdev->irq = err; |
| 1389 | return 0; |
| 1390 | |
| 1391 | fail: |
| 1392 | return err; |
| 1393 | } |
| 1394 | |
| 1395 | /* Common code used when first setting up, and when resuming. */ |
| 1396 | static int talk_to_backend(struct xenbus_device *dev, |
| 1397 | struct netfront_info *info) |
| 1398 | { |
| 1399 | const char *message; |
| 1400 | struct xenbus_transaction xbt; |
| 1401 | int err; |
| 1402 | |
| 1403 | /* Create shared ring, alloc event channel. */ |
| 1404 | err = setup_netfront(dev, info); |
| 1405 | if (err) |
| 1406 | goto out; |
| 1407 | |
| 1408 | again: |
| 1409 | err = xenbus_transaction_start(&xbt); |
| 1410 | if (err) { |
| 1411 | xenbus_dev_fatal(dev, err, "starting transaction"); |
| 1412 | goto destroy_ring; |
| 1413 | } |
| 1414 | |
| 1415 | err = xenbus_printf(xbt, dev->nodename, "tx-ring-ref", "%u", |
| 1416 | info->tx_ring_ref); |
| 1417 | if (err) { |
| 1418 | message = "writing tx ring-ref"; |
| 1419 | goto abort_transaction; |
| 1420 | } |
| 1421 | err = xenbus_printf(xbt, dev->nodename, "rx-ring-ref", "%u", |
| 1422 | info->rx_ring_ref); |
| 1423 | if (err) { |
| 1424 | message = "writing rx ring-ref"; |
| 1425 | goto abort_transaction; |
| 1426 | } |
| 1427 | err = xenbus_printf(xbt, dev->nodename, |
| 1428 | "event-channel", "%u", info->evtchn); |
| 1429 | if (err) { |
| 1430 | message = "writing event-channel"; |
| 1431 | goto abort_transaction; |
| 1432 | } |
| 1433 | |
| 1434 | err = xenbus_printf(xbt, dev->nodename, "request-rx-copy", "%u", |
| 1435 | 1); |
| 1436 | if (err) { |
| 1437 | message = "writing request-rx-copy"; |
| 1438 | goto abort_transaction; |
| 1439 | } |
| 1440 | |
| 1441 | err = xenbus_printf(xbt, dev->nodename, "feature-rx-notify", "%d", 1); |
| 1442 | if (err) { |
| 1443 | message = "writing feature-rx-notify"; |
| 1444 | goto abort_transaction; |
| 1445 | } |
| 1446 | |
| 1447 | err = xenbus_printf(xbt, dev->nodename, "feature-sg", "%d", 1); |
| 1448 | if (err) { |
| 1449 | message = "writing feature-sg"; |
| 1450 | goto abort_transaction; |
| 1451 | } |
| 1452 | |
| 1453 | err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv4", "%d", 1); |
| 1454 | if (err) { |
| 1455 | message = "writing feature-gso-tcpv4"; |
| 1456 | goto abort_transaction; |
| 1457 | } |
| 1458 | |
| 1459 | err = xenbus_transaction_end(xbt, 0); |
| 1460 | if (err) { |
| 1461 | if (err == -EAGAIN) |
| 1462 | goto again; |
| 1463 | xenbus_dev_fatal(dev, err, "completing transaction"); |
| 1464 | goto destroy_ring; |
| 1465 | } |
| 1466 | |
| 1467 | return 0; |
| 1468 | |
| 1469 | abort_transaction: |
| 1470 | xenbus_transaction_end(xbt, 1); |
| 1471 | xenbus_dev_fatal(dev, err, "%s", message); |
| 1472 | destroy_ring: |
| 1473 | xennet_disconnect_backend(info); |
| 1474 | out: |
| 1475 | return err; |
| 1476 | } |
| 1477 | |
| 1478 | static int xennet_set_sg(struct net_device *dev, u32 data) |
| 1479 | { |
| 1480 | if (data) { |
| 1481 | struct netfront_info *np = netdev_priv(dev); |
| 1482 | int val; |
| 1483 | |
| 1484 | if (xenbus_scanf(XBT_NIL, np->xbdev->otherend, "feature-sg", |
| 1485 | "%d", &val) < 0) |
| 1486 | val = 0; |
| 1487 | if (!val) |
| 1488 | return -ENOSYS; |
| 1489 | } else if (dev->mtu > ETH_DATA_LEN) |
| 1490 | dev->mtu = ETH_DATA_LEN; |
| 1491 | |
| 1492 | return ethtool_op_set_sg(dev, data); |
| 1493 | } |
| 1494 | |
| 1495 | static int xennet_set_tso(struct net_device *dev, u32 data) |
| 1496 | { |
| 1497 | if (data) { |
| 1498 | struct netfront_info *np = netdev_priv(dev); |
| 1499 | int val; |
| 1500 | |
| 1501 | if (xenbus_scanf(XBT_NIL, np->xbdev->otherend, |
| 1502 | "feature-gso-tcpv4", "%d", &val) < 0) |
| 1503 | val = 0; |
| 1504 | if (!val) |
| 1505 | return -ENOSYS; |
| 1506 | } |
| 1507 | |
| 1508 | return ethtool_op_set_tso(dev, data); |
| 1509 | } |
| 1510 | |
| 1511 | static void xennet_set_features(struct net_device *dev) |
| 1512 | { |
| 1513 | /* Turn off all GSO bits except ROBUST. */ |
| 1514 | dev->features &= ~NETIF_F_GSO_MASK; |
| 1515 | dev->features |= NETIF_F_GSO_ROBUST; |
| 1516 | xennet_set_sg(dev, 0); |
| 1517 | |
| 1518 | /* We need checksum offload to enable scatter/gather and TSO. */ |
| 1519 | if (!(dev->features & NETIF_F_IP_CSUM)) |
| 1520 | return; |
| 1521 | |
| 1522 | if (!xennet_set_sg(dev, 1)) |
| 1523 | xennet_set_tso(dev, 1); |
| 1524 | } |
| 1525 | |
| 1526 | static int xennet_connect(struct net_device *dev) |
| 1527 | { |
| 1528 | struct netfront_info *np = netdev_priv(dev); |
| 1529 | int i, requeue_idx, err; |
| 1530 | struct sk_buff *skb; |
| 1531 | grant_ref_t ref; |
| 1532 | struct xen_netif_rx_request *req; |
| 1533 | unsigned int feature_rx_copy; |
| 1534 | |
| 1535 | err = xenbus_scanf(XBT_NIL, np->xbdev->otherend, |
| 1536 | "feature-rx-copy", "%u", &feature_rx_copy); |
| 1537 | if (err != 1) |
| 1538 | feature_rx_copy = 0; |
| 1539 | |
| 1540 | if (!feature_rx_copy) { |
| 1541 | dev_info(&dev->dev, |
| 1542 | "backend does not support copying receive path\n"); |
| 1543 | return -ENODEV; |
| 1544 | } |
| 1545 | |
| 1546 | err = talk_to_backend(np->xbdev, np); |
| 1547 | if (err) |
| 1548 | return err; |
| 1549 | |
| 1550 | xennet_set_features(dev); |
| 1551 | |
| 1552 | spin_lock_bh(&np->rx_lock); |
| 1553 | spin_lock_irq(&np->tx_lock); |
| 1554 | |
| 1555 | /* Step 1: Discard all pending TX packet fragments. */ |
| 1556 | xennet_release_tx_bufs(np); |
| 1557 | |
| 1558 | /* Step 2: Rebuild the RX buffer freelist and the RX ring itself. */ |
| 1559 | for (requeue_idx = 0, i = 0; i < NET_RX_RING_SIZE; i++) { |
| 1560 | if (!np->rx_skbs[i]) |
| 1561 | continue; |
| 1562 | |
| 1563 | skb = np->rx_skbs[requeue_idx] = xennet_get_rx_skb(np, i); |
| 1564 | ref = np->grant_rx_ref[requeue_idx] = xennet_get_rx_ref(np, i); |
| 1565 | req = RING_GET_REQUEST(&np->rx, requeue_idx); |
| 1566 | |
| 1567 | gnttab_grant_foreign_access_ref( |
| 1568 | ref, np->xbdev->otherend_id, |
| 1569 | pfn_to_mfn(page_to_pfn(skb_shinfo(skb)-> |
| 1570 | frags->page)), |
| 1571 | 0); |
| 1572 | req->gref = ref; |
| 1573 | req->id = requeue_idx; |
| 1574 | |
| 1575 | requeue_idx++; |
| 1576 | } |
| 1577 | |
| 1578 | np->rx.req_prod_pvt = requeue_idx; |
| 1579 | |
| 1580 | /* |
| 1581 | * Step 3: All public and private state should now be sane. Get |
| 1582 | * ready to start sending and receiving packets and give the driver |
| 1583 | * domain a kick because we've probably just requeued some |
| 1584 | * packets. |
| 1585 | */ |
| 1586 | netif_carrier_on(np->netdev); |
| 1587 | notify_remote_via_irq(np->netdev->irq); |
| 1588 | xennet_tx_buf_gc(dev); |
| 1589 | xennet_alloc_rx_buffers(dev); |
| 1590 | |
| 1591 | spin_unlock_irq(&np->tx_lock); |
| 1592 | spin_unlock_bh(&np->rx_lock); |
| 1593 | |
| 1594 | return 0; |
| 1595 | } |
| 1596 | |
| 1597 | /** |
| 1598 | * Callback received when the backend's state changes. |
| 1599 | */ |
| 1600 | static void backend_changed(struct xenbus_device *dev, |
| 1601 | enum xenbus_state backend_state) |
| 1602 | { |
| 1603 | struct netfront_info *np = dev_get_drvdata(&dev->dev); |
| 1604 | struct net_device *netdev = np->netdev; |
| 1605 | |
| 1606 | dev_dbg(&dev->dev, "%s\n", xenbus_strstate(backend_state)); |
| 1607 | |
| 1608 | switch (backend_state) { |
| 1609 | case XenbusStateInitialising: |
| 1610 | case XenbusStateInitialised: |
| 1611 | case XenbusStateConnected: |
| 1612 | case XenbusStateUnknown: |
| 1613 | case XenbusStateClosed: |
| 1614 | break; |
| 1615 | |
| 1616 | case XenbusStateInitWait: |
| 1617 | if (dev->state != XenbusStateInitialising) |
| 1618 | break; |
| 1619 | if (xennet_connect(netdev) != 0) |
| 1620 | break; |
| 1621 | xenbus_switch_state(dev, XenbusStateConnected); |
| 1622 | break; |
| 1623 | |
| 1624 | case XenbusStateClosing: |
| 1625 | xenbus_frontend_closed(dev); |
| 1626 | break; |
| 1627 | } |
| 1628 | } |
| 1629 | |
| 1630 | static const struct ethtool_ops xennet_ethtool_ops = |
| 1631 | { |
| 1632 | .set_tx_csum = ethtool_op_set_tx_csum, |
| 1633 | .set_sg = xennet_set_sg, |
| 1634 | .set_tso = xennet_set_tso, |
| 1635 | .get_link = ethtool_op_get_link, |
| 1636 | }; |
| 1637 | |
| 1638 | #ifdef CONFIG_SYSFS |
| 1639 | static ssize_t show_rxbuf_min(struct device *dev, |
| 1640 | struct device_attribute *attr, char *buf) |
| 1641 | { |
| 1642 | struct net_device *netdev = to_net_dev(dev); |
| 1643 | struct netfront_info *info = netdev_priv(netdev); |
| 1644 | |
| 1645 | return sprintf(buf, "%u\n", info->rx_min_target); |
| 1646 | } |
| 1647 | |
| 1648 | static ssize_t store_rxbuf_min(struct device *dev, |
| 1649 | struct device_attribute *attr, |
| 1650 | const char *buf, size_t len) |
| 1651 | { |
| 1652 | struct net_device *netdev = to_net_dev(dev); |
| 1653 | struct netfront_info *np = netdev_priv(netdev); |
| 1654 | char *endp; |
| 1655 | unsigned long target; |
| 1656 | |
| 1657 | if (!capable(CAP_NET_ADMIN)) |
| 1658 | return -EPERM; |
| 1659 | |
| 1660 | target = simple_strtoul(buf, &endp, 0); |
| 1661 | if (endp == buf) |
| 1662 | return -EBADMSG; |
| 1663 | |
| 1664 | if (target < RX_MIN_TARGET) |
| 1665 | target = RX_MIN_TARGET; |
| 1666 | if (target > RX_MAX_TARGET) |
| 1667 | target = RX_MAX_TARGET; |
| 1668 | |
| 1669 | spin_lock_bh(&np->rx_lock); |
| 1670 | if (target > np->rx_max_target) |
| 1671 | np->rx_max_target = target; |
| 1672 | np->rx_min_target = target; |
| 1673 | if (target > np->rx_target) |
| 1674 | np->rx_target = target; |
| 1675 | |
| 1676 | xennet_alloc_rx_buffers(netdev); |
| 1677 | |
| 1678 | spin_unlock_bh(&np->rx_lock); |
| 1679 | return len; |
| 1680 | } |
| 1681 | |
| 1682 | static ssize_t show_rxbuf_max(struct device *dev, |
| 1683 | struct device_attribute *attr, char *buf) |
| 1684 | { |
| 1685 | struct net_device *netdev = to_net_dev(dev); |
| 1686 | struct netfront_info *info = netdev_priv(netdev); |
| 1687 | |
| 1688 | return sprintf(buf, "%u\n", info->rx_max_target); |
| 1689 | } |
| 1690 | |
| 1691 | static ssize_t store_rxbuf_max(struct device *dev, |
| 1692 | struct device_attribute *attr, |
| 1693 | const char *buf, size_t len) |
| 1694 | { |
| 1695 | struct net_device *netdev = to_net_dev(dev); |
| 1696 | struct netfront_info *np = netdev_priv(netdev); |
| 1697 | char *endp; |
| 1698 | unsigned long target; |
| 1699 | |
| 1700 | if (!capable(CAP_NET_ADMIN)) |
| 1701 | return -EPERM; |
| 1702 | |
| 1703 | target = simple_strtoul(buf, &endp, 0); |
| 1704 | if (endp == buf) |
| 1705 | return -EBADMSG; |
| 1706 | |
| 1707 | if (target < RX_MIN_TARGET) |
| 1708 | target = RX_MIN_TARGET; |
| 1709 | if (target > RX_MAX_TARGET) |
| 1710 | target = RX_MAX_TARGET; |
| 1711 | |
| 1712 | spin_lock_bh(&np->rx_lock); |
| 1713 | if (target < np->rx_min_target) |
| 1714 | np->rx_min_target = target; |
| 1715 | np->rx_max_target = target; |
| 1716 | if (target < np->rx_target) |
| 1717 | np->rx_target = target; |
| 1718 | |
| 1719 | xennet_alloc_rx_buffers(netdev); |
| 1720 | |
| 1721 | spin_unlock_bh(&np->rx_lock); |
| 1722 | return len; |
| 1723 | } |
| 1724 | |
| 1725 | static ssize_t show_rxbuf_cur(struct device *dev, |
| 1726 | struct device_attribute *attr, char *buf) |
| 1727 | { |
| 1728 | struct net_device *netdev = to_net_dev(dev); |
| 1729 | struct netfront_info *info = netdev_priv(netdev); |
| 1730 | |
| 1731 | return sprintf(buf, "%u\n", info->rx_target); |
| 1732 | } |
| 1733 | |
| 1734 | static struct device_attribute xennet_attrs[] = { |
| 1735 | __ATTR(rxbuf_min, S_IRUGO|S_IWUSR, show_rxbuf_min, store_rxbuf_min), |
| 1736 | __ATTR(rxbuf_max, S_IRUGO|S_IWUSR, show_rxbuf_max, store_rxbuf_max), |
| 1737 | __ATTR(rxbuf_cur, S_IRUGO, show_rxbuf_cur, NULL), |
| 1738 | }; |
| 1739 | |
| 1740 | static int xennet_sysfs_addif(struct net_device *netdev) |
| 1741 | { |
| 1742 | int i; |
| 1743 | int err; |
| 1744 | |
| 1745 | for (i = 0; i < ARRAY_SIZE(xennet_attrs); i++) { |
| 1746 | err = device_create_file(&netdev->dev, |
| 1747 | &xennet_attrs[i]); |
| 1748 | if (err) |
| 1749 | goto fail; |
| 1750 | } |
| 1751 | return 0; |
| 1752 | |
| 1753 | fail: |
| 1754 | while (--i >= 0) |
| 1755 | device_remove_file(&netdev->dev, &xennet_attrs[i]); |
| 1756 | return err; |
| 1757 | } |
| 1758 | |
| 1759 | static void xennet_sysfs_delif(struct net_device *netdev) |
| 1760 | { |
| 1761 | int i; |
| 1762 | |
| 1763 | for (i = 0; i < ARRAY_SIZE(xennet_attrs); i++) |
| 1764 | device_remove_file(&netdev->dev, &xennet_attrs[i]); |
| 1765 | } |
| 1766 | |
| 1767 | #endif /* CONFIG_SYSFS */ |
| 1768 | |
| 1769 | static struct xenbus_device_id netfront_ids[] = { |
| 1770 | { "vif" }, |
| 1771 | { "" } |
| 1772 | }; |
| 1773 | |
| 1774 | |
| 1775 | static int __devexit xennet_remove(struct xenbus_device *dev) |
| 1776 | { |
| 1777 | struct netfront_info *info = dev_get_drvdata(&dev->dev); |
| 1778 | |
| 1779 | dev_dbg(&dev->dev, "%s\n", dev->nodename); |
| 1780 | |
| 1781 | unregister_netdev(info->netdev); |
| 1782 | |
| 1783 | xennet_disconnect_backend(info); |
| 1784 | |
| 1785 | del_timer_sync(&info->rx_refill_timer); |
| 1786 | |
| 1787 | xennet_sysfs_delif(info->netdev); |
| 1788 | |
| 1789 | free_netdev(info->netdev); |
| 1790 | |
| 1791 | return 0; |
| 1792 | } |
| 1793 | |
| 1794 | static struct xenbus_driver netfront_driver = { |
| 1795 | .name = "vif", |
| 1796 | .owner = THIS_MODULE, |
| 1797 | .ids = netfront_ids, |
| 1798 | .probe = netfront_probe, |
| 1799 | .remove = __devexit_p(xennet_remove), |
| 1800 | .resume = netfront_resume, |
| 1801 | .otherend_changed = backend_changed, |
| 1802 | }; |
| 1803 | |
| 1804 | static int __init netif_init(void) |
| 1805 | { |
| 1806 | if (!xen_domain()) |
| 1807 | return -ENODEV; |
| 1808 | |
| 1809 | if (xen_initial_domain()) |
| 1810 | return 0; |
| 1811 | |
| 1812 | printk(KERN_INFO "Initialising Xen virtual ethernet driver.\n"); |
| 1813 | |
| 1814 | return xenbus_register_frontend(&netfront_driver); |
| 1815 | } |
| 1816 | module_init(netif_init); |
| 1817 | |
| 1818 | |
| 1819 | static void __exit netif_exit(void) |
| 1820 | { |
| 1821 | if (xen_initial_domain()) |
| 1822 | return; |
| 1823 | |
| 1824 | xenbus_unregister_driver(&netfront_driver); |
| 1825 | } |
| 1826 | module_exit(netif_exit); |
| 1827 | |
| 1828 | MODULE_DESCRIPTION("Xen virtual network device frontend"); |
| 1829 | MODULE_LICENSE("GPL"); |
| 1830 | MODULE_ALIAS("xen:vif"); |
| 1831 | MODULE_ALIAS("xennet"); |