Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Back-end of the driver for virtual network devices. This portion of the |
| 3 | * driver exports a 'unified' network-device interface that can be accessed |
| 4 | * by any operating system that implements a compatible front end. A |
| 5 | * reference front-end implementation can be found in: |
| 6 | * drivers/net/xen-netfront.c |
| 7 | * |
| 8 | * Copyright (c) 2002-2005, K A Fraser |
| 9 | * |
| 10 | * This program is free software; you can redistribute it and/or |
| 11 | * modify it under the terms of the GNU General Public License version 2 |
| 12 | * as published by the Free Software Foundation; or, when distributed |
| 13 | * separately from the Linux kernel or incorporated into other |
| 14 | * software packages, subject to the following license: |
| 15 | * |
| 16 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 17 | * of this source file (the "Software"), to deal in the Software without |
| 18 | * restriction, including without limitation the rights to use, copy, modify, |
| 19 | * merge, publish, distribute, sublicense, and/or sell copies of the Software, |
| 20 | * and to permit persons to whom the Software is furnished to do so, subject to |
| 21 | * the following conditions: |
| 22 | * |
| 23 | * The above copyright notice and this permission notice shall be included in |
| 24 | * all copies or substantial portions of the Software. |
| 25 | * |
| 26 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 27 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 28 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| 29 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 30 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
| 31 | * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS |
| 32 | * IN THE SOFTWARE. |
| 33 | */ |
| 34 | |
| 35 | #include "common.h" |
| 36 | |
| 37 | #include <linux/kthread.h> |
| 38 | #include <linux/if_vlan.h> |
| 39 | #include <linux/udp.h> |
| 40 | |
| 41 | #include <net/tcp.h> |
| 42 | |
Stefano Stabellini | ca98163 | 2012-08-08 17:21:23 +0000 | [diff] [blame] | 43 | #include <xen/xen.h> |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 44 | #include <xen/events.h> |
| 45 | #include <xen/interface/memory.h> |
| 46 | |
| 47 | #include <asm/xen/hypercall.h> |
| 48 | #include <asm/xen/page.h> |
| 49 | |
| 50 | struct pending_tx_info { |
| 51 | struct xen_netif_tx_request req; |
| 52 | struct xenvif *vif; |
| 53 | }; |
| 54 | typedef unsigned int pending_ring_idx_t; |
| 55 | |
| 56 | struct netbk_rx_meta { |
| 57 | int id; |
| 58 | int size; |
| 59 | int gso_size; |
| 60 | }; |
| 61 | |
| 62 | #define MAX_PENDING_REQS 256 |
| 63 | |
Ian Campbell | ea066ad | 2011-10-05 00:28:46 +0000 | [diff] [blame] | 64 | /* Discriminate from any valid pending_idx value. */ |
| 65 | #define INVALID_PENDING_IDX 0xFFFF |
| 66 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 67 | #define MAX_BUFFER_OFFSET PAGE_SIZE |
| 68 | |
| 69 | /* extra field used in struct page */ |
| 70 | union page_ext { |
| 71 | struct { |
| 72 | #if BITS_PER_LONG < 64 |
| 73 | #define IDX_WIDTH 8 |
| 74 | #define GROUP_WIDTH (BITS_PER_LONG - IDX_WIDTH) |
| 75 | unsigned int group:GROUP_WIDTH; |
| 76 | unsigned int idx:IDX_WIDTH; |
| 77 | #else |
| 78 | unsigned int group, idx; |
| 79 | #endif |
| 80 | } e; |
| 81 | void *mapping; |
| 82 | }; |
| 83 | |
| 84 | struct xen_netbk { |
| 85 | wait_queue_head_t wq; |
| 86 | struct task_struct *task; |
| 87 | |
| 88 | struct sk_buff_head rx_queue; |
| 89 | struct sk_buff_head tx_queue; |
| 90 | |
| 91 | struct timer_list net_timer; |
| 92 | |
| 93 | struct page *mmap_pages[MAX_PENDING_REQS]; |
| 94 | |
| 95 | pending_ring_idx_t pending_prod; |
| 96 | pending_ring_idx_t pending_cons; |
| 97 | struct list_head net_schedule_list; |
| 98 | |
| 99 | /* Protect the net_schedule_list in netif. */ |
| 100 | spinlock_t net_schedule_list_lock; |
| 101 | |
| 102 | atomic_t netfront_count; |
| 103 | |
| 104 | struct pending_tx_info pending_tx_info[MAX_PENDING_REQS]; |
| 105 | struct gnttab_copy tx_copy_ops[MAX_PENDING_REQS]; |
| 106 | |
| 107 | u16 pending_ring[MAX_PENDING_REQS]; |
| 108 | |
| 109 | /* |
| 110 | * Given MAX_BUFFER_OFFSET of 4096 the worst case is that each |
| 111 | * head/fragment page uses 2 copy operations because it |
| 112 | * straddles two buffers in the frontend. |
| 113 | */ |
| 114 | struct gnttab_copy grant_copy_op[2*XEN_NETIF_RX_RING_SIZE]; |
| 115 | struct netbk_rx_meta meta[2*XEN_NETIF_RX_RING_SIZE]; |
| 116 | }; |
| 117 | |
| 118 | static struct xen_netbk *xen_netbk; |
| 119 | static int xen_netbk_group_nr; |
| 120 | |
| 121 | void xen_netbk_add_xenvif(struct xenvif *vif) |
| 122 | { |
| 123 | int i; |
| 124 | int min_netfront_count; |
| 125 | int min_group = 0; |
| 126 | struct xen_netbk *netbk; |
| 127 | |
| 128 | min_netfront_count = atomic_read(&xen_netbk[0].netfront_count); |
| 129 | for (i = 0; i < xen_netbk_group_nr; i++) { |
| 130 | int netfront_count = atomic_read(&xen_netbk[i].netfront_count); |
| 131 | if (netfront_count < min_netfront_count) { |
| 132 | min_group = i; |
| 133 | min_netfront_count = netfront_count; |
| 134 | } |
| 135 | } |
| 136 | |
| 137 | netbk = &xen_netbk[min_group]; |
| 138 | |
| 139 | vif->netbk = netbk; |
| 140 | atomic_inc(&netbk->netfront_count); |
| 141 | } |
| 142 | |
| 143 | void xen_netbk_remove_xenvif(struct xenvif *vif) |
| 144 | { |
| 145 | struct xen_netbk *netbk = vif->netbk; |
| 146 | vif->netbk = NULL; |
| 147 | atomic_dec(&netbk->netfront_count); |
| 148 | } |
| 149 | |
Matthew Daley | 7d5145d | 2013-02-06 23:41:36 +0000 | [diff] [blame] | 150 | static void xen_netbk_idx_release(struct xen_netbk *netbk, u16 pending_idx, |
| 151 | u8 status); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 152 | static void make_tx_response(struct xenvif *vif, |
| 153 | struct xen_netif_tx_request *txp, |
| 154 | s8 st); |
| 155 | static struct xen_netif_rx_response *make_rx_response(struct xenvif *vif, |
| 156 | u16 id, |
| 157 | s8 st, |
| 158 | u16 offset, |
| 159 | u16 size, |
| 160 | u16 flags); |
| 161 | |
| 162 | static inline unsigned long idx_to_pfn(struct xen_netbk *netbk, |
Ian Campbell | ea066ad | 2011-10-05 00:28:46 +0000 | [diff] [blame] | 163 | u16 idx) |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 164 | { |
| 165 | return page_to_pfn(netbk->mmap_pages[idx]); |
| 166 | } |
| 167 | |
| 168 | static inline unsigned long idx_to_kaddr(struct xen_netbk *netbk, |
Ian Campbell | ea066ad | 2011-10-05 00:28:46 +0000 | [diff] [blame] | 169 | u16 idx) |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 170 | { |
| 171 | return (unsigned long)pfn_to_kaddr(idx_to_pfn(netbk, idx)); |
| 172 | } |
| 173 | |
| 174 | /* extra field used in struct page */ |
| 175 | static inline void set_page_ext(struct page *pg, struct xen_netbk *netbk, |
| 176 | unsigned int idx) |
| 177 | { |
| 178 | unsigned int group = netbk - xen_netbk; |
| 179 | union page_ext ext = { .e = { .group = group + 1, .idx = idx } }; |
| 180 | |
| 181 | BUILD_BUG_ON(sizeof(ext) > sizeof(ext.mapping)); |
| 182 | pg->mapping = ext.mapping; |
| 183 | } |
| 184 | |
| 185 | static int get_page_ext(struct page *pg, |
| 186 | unsigned int *pgroup, unsigned int *pidx) |
| 187 | { |
| 188 | union page_ext ext = { .mapping = pg->mapping }; |
| 189 | struct xen_netbk *netbk; |
| 190 | unsigned int group, idx; |
| 191 | |
| 192 | group = ext.e.group - 1; |
| 193 | |
| 194 | if (group < 0 || group >= xen_netbk_group_nr) |
| 195 | return 0; |
| 196 | |
| 197 | netbk = &xen_netbk[group]; |
| 198 | |
| 199 | idx = ext.e.idx; |
| 200 | |
| 201 | if ((idx < 0) || (idx >= MAX_PENDING_REQS)) |
| 202 | return 0; |
| 203 | |
| 204 | if (netbk->mmap_pages[idx] != pg) |
| 205 | return 0; |
| 206 | |
| 207 | *pgroup = group; |
| 208 | *pidx = idx; |
| 209 | |
| 210 | return 1; |
| 211 | } |
| 212 | |
| 213 | /* |
| 214 | * This is the amount of packet we copy rather than map, so that the |
| 215 | * guest can't fiddle with the contents of the headers while we do |
| 216 | * packet processing on them (netfilter, routing, etc). |
| 217 | */ |
| 218 | #define PKT_PROT_LEN (ETH_HLEN + \ |
| 219 | VLAN_HLEN + \ |
| 220 | sizeof(struct iphdr) + MAX_IPOPTLEN + \ |
| 221 | sizeof(struct tcphdr) + MAX_TCP_OPTION_SPACE) |
| 222 | |
Ian Campbell | ea066ad | 2011-10-05 00:28:46 +0000 | [diff] [blame] | 223 | static u16 frag_get_pending_idx(skb_frag_t *frag) |
| 224 | { |
| 225 | return (u16)frag->page_offset; |
| 226 | } |
| 227 | |
| 228 | static void frag_set_pending_idx(skb_frag_t *frag, u16 pending_idx) |
| 229 | { |
| 230 | frag->page_offset = pending_idx; |
| 231 | } |
| 232 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 233 | static inline pending_ring_idx_t pending_index(unsigned i) |
| 234 | { |
| 235 | return i & (MAX_PENDING_REQS-1); |
| 236 | } |
| 237 | |
| 238 | static inline pending_ring_idx_t nr_pending_reqs(struct xen_netbk *netbk) |
| 239 | { |
| 240 | return MAX_PENDING_REQS - |
| 241 | netbk->pending_prod + netbk->pending_cons; |
| 242 | } |
| 243 | |
| 244 | static void xen_netbk_kick_thread(struct xen_netbk *netbk) |
| 245 | { |
| 246 | wake_up(&netbk->wq); |
| 247 | } |
| 248 | |
| 249 | static int max_required_rx_slots(struct xenvif *vif) |
| 250 | { |
| 251 | int max = DIV_ROUND_UP(vif->dev->mtu, PAGE_SIZE); |
| 252 | |
| 253 | if (vif->can_sg || vif->gso || vif->gso_prefix) |
| 254 | max += MAX_SKB_FRAGS + 1; /* extra_info + frags */ |
| 255 | |
| 256 | return max; |
| 257 | } |
| 258 | |
| 259 | int xen_netbk_rx_ring_full(struct xenvif *vif) |
| 260 | { |
| 261 | RING_IDX peek = vif->rx_req_cons_peek; |
| 262 | RING_IDX needed = max_required_rx_slots(vif); |
| 263 | |
| 264 | return ((vif->rx.sring->req_prod - peek) < needed) || |
| 265 | ((vif->rx.rsp_prod_pvt + XEN_NETIF_RX_RING_SIZE - peek) < needed); |
| 266 | } |
| 267 | |
| 268 | int xen_netbk_must_stop_queue(struct xenvif *vif) |
| 269 | { |
| 270 | if (!xen_netbk_rx_ring_full(vif)) |
| 271 | return 0; |
| 272 | |
| 273 | vif->rx.sring->req_event = vif->rx_req_cons_peek + |
| 274 | max_required_rx_slots(vif); |
| 275 | mb(); /* request notification /then/ check the queue */ |
| 276 | |
| 277 | return xen_netbk_rx_ring_full(vif); |
| 278 | } |
| 279 | |
| 280 | /* |
| 281 | * Returns true if we should start a new receive buffer instead of |
| 282 | * adding 'size' bytes to a buffer which currently contains 'offset' |
| 283 | * bytes. |
| 284 | */ |
| 285 | static bool start_new_rx_buffer(int offset, unsigned long size, int head) |
| 286 | { |
| 287 | /* simple case: we have completely filled the current buffer. */ |
| 288 | if (offset == MAX_BUFFER_OFFSET) |
| 289 | return true; |
| 290 | |
| 291 | /* |
| 292 | * complex case: start a fresh buffer if the current frag |
| 293 | * would overflow the current buffer but only if: |
| 294 | * (i) this frag would fit completely in the next buffer |
| 295 | * and (ii) there is already some data in the current buffer |
| 296 | * and (iii) this is not the head buffer. |
| 297 | * |
| 298 | * Where: |
| 299 | * - (i) stops us splitting a frag into two copies |
| 300 | * unless the frag is too large for a single buffer. |
| 301 | * - (ii) stops us from leaving a buffer pointlessly empty. |
| 302 | * - (iii) stops us leaving the first buffer |
| 303 | * empty. Strictly speaking this is already covered |
| 304 | * by (ii) but is explicitly checked because |
| 305 | * netfront relies on the first buffer being |
| 306 | * non-empty and can crash otherwise. |
| 307 | * |
| 308 | * This means we will effectively linearise small |
| 309 | * frags but do not needlessly split large buffers |
| 310 | * into multiple copies tend to give large frags their |
| 311 | * own buffers as before. |
| 312 | */ |
| 313 | if ((offset + size > MAX_BUFFER_OFFSET) && |
| 314 | (size <= MAX_BUFFER_OFFSET) && offset && !head) |
| 315 | return true; |
| 316 | |
| 317 | return false; |
| 318 | } |
| 319 | |
| 320 | /* |
| 321 | * Figure out how many ring slots we're going to need to send @skb to |
| 322 | * the guest. This function is essentially a dry run of |
| 323 | * netbk_gop_frag_copy. |
| 324 | */ |
| 325 | unsigned int xen_netbk_count_skb_slots(struct xenvif *vif, struct sk_buff *skb) |
| 326 | { |
| 327 | unsigned int count; |
| 328 | int i, copy_off; |
| 329 | |
Simon Graham | e26b203 | 2012-05-24 06:26:07 +0000 | [diff] [blame] | 330 | count = DIV_ROUND_UP(skb_headlen(skb), PAGE_SIZE); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 331 | |
| 332 | copy_off = skb_headlen(skb) % PAGE_SIZE; |
| 333 | |
| 334 | if (skb_shinfo(skb)->gso_size) |
| 335 | count++; |
| 336 | |
| 337 | for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { |
Eric Dumazet | 9e903e0 | 2011-10-18 21:00:24 +0000 | [diff] [blame] | 338 | unsigned long size = skb_frag_size(&skb_shinfo(skb)->frags[i]); |
Ian Campbell | 6a8ed46 | 2012-10-10 03:48:42 +0000 | [diff] [blame] | 339 | unsigned long offset = skb_shinfo(skb)->frags[i].page_offset; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 340 | unsigned long bytes; |
Ian Campbell | 6a8ed46 | 2012-10-10 03:48:42 +0000 | [diff] [blame] | 341 | |
| 342 | offset &= ~PAGE_MASK; |
| 343 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 344 | while (size > 0) { |
Ian Campbell | 6a8ed46 | 2012-10-10 03:48:42 +0000 | [diff] [blame] | 345 | BUG_ON(offset >= PAGE_SIZE); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 346 | BUG_ON(copy_off > MAX_BUFFER_OFFSET); |
| 347 | |
Ian Campbell | 6a8ed46 | 2012-10-10 03:48:42 +0000 | [diff] [blame] | 348 | bytes = PAGE_SIZE - offset; |
| 349 | |
| 350 | if (bytes > size) |
| 351 | bytes = size; |
| 352 | |
| 353 | if (start_new_rx_buffer(copy_off, bytes, 0)) { |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 354 | count++; |
| 355 | copy_off = 0; |
| 356 | } |
| 357 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 358 | if (copy_off + bytes > MAX_BUFFER_OFFSET) |
| 359 | bytes = MAX_BUFFER_OFFSET - copy_off; |
| 360 | |
| 361 | copy_off += bytes; |
Ian Campbell | 6a8ed46 | 2012-10-10 03:48:42 +0000 | [diff] [blame] | 362 | |
| 363 | offset += bytes; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 364 | size -= bytes; |
Ian Campbell | 6a8ed46 | 2012-10-10 03:48:42 +0000 | [diff] [blame] | 365 | |
| 366 | if (offset == PAGE_SIZE) |
| 367 | offset = 0; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 368 | } |
| 369 | } |
| 370 | return count; |
| 371 | } |
| 372 | |
| 373 | struct netrx_pending_operations { |
| 374 | unsigned copy_prod, copy_cons; |
| 375 | unsigned meta_prod, meta_cons; |
| 376 | struct gnttab_copy *copy; |
| 377 | struct netbk_rx_meta *meta; |
| 378 | int copy_off; |
| 379 | grant_ref_t copy_gref; |
| 380 | }; |
| 381 | |
| 382 | static struct netbk_rx_meta *get_next_rx_buffer(struct xenvif *vif, |
| 383 | struct netrx_pending_operations *npo) |
| 384 | { |
| 385 | struct netbk_rx_meta *meta; |
| 386 | struct xen_netif_rx_request *req; |
| 387 | |
| 388 | req = RING_GET_REQUEST(&vif->rx, vif->rx.req_cons++); |
| 389 | |
| 390 | meta = npo->meta + npo->meta_prod++; |
| 391 | meta->gso_size = 0; |
| 392 | meta->size = 0; |
| 393 | meta->id = req->id; |
| 394 | |
| 395 | npo->copy_off = 0; |
| 396 | npo->copy_gref = req->gref; |
| 397 | |
| 398 | return meta; |
| 399 | } |
| 400 | |
| 401 | /* |
| 402 | * Set up the grant operations for this fragment. If it's a flipping |
| 403 | * interface, we also set up the unmap request from here. |
| 404 | */ |
| 405 | static void netbk_gop_frag_copy(struct xenvif *vif, struct sk_buff *skb, |
| 406 | struct netrx_pending_operations *npo, |
| 407 | struct page *page, unsigned long size, |
| 408 | unsigned long offset, int *head) |
| 409 | { |
| 410 | struct gnttab_copy *copy_gop; |
| 411 | struct netbk_rx_meta *meta; |
| 412 | /* |
Wei Liu | e34c024 | 2011-12-06 02:04:50 +0000 | [diff] [blame] | 413 | * These variables are used iff get_page_ext returns true, |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 414 | * in which case they are guaranteed to be initialized. |
| 415 | */ |
| 416 | unsigned int uninitialized_var(group), uninitialized_var(idx); |
| 417 | int foreign = get_page_ext(page, &group, &idx); |
| 418 | unsigned long bytes; |
| 419 | |
| 420 | /* Data must not cross a page boundary. */ |
Ian Campbell | 6a8ed46 | 2012-10-10 03:48:42 +0000 | [diff] [blame] | 421 | BUG_ON(size + offset > PAGE_SIZE<<compound_order(page)); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 422 | |
| 423 | meta = npo->meta + npo->meta_prod - 1; |
| 424 | |
Ian Campbell | 6a8ed46 | 2012-10-10 03:48:42 +0000 | [diff] [blame] | 425 | /* Skip unused frames from start of page */ |
| 426 | page += offset >> PAGE_SHIFT; |
| 427 | offset &= ~PAGE_MASK; |
| 428 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 429 | while (size > 0) { |
Ian Campbell | 6a8ed46 | 2012-10-10 03:48:42 +0000 | [diff] [blame] | 430 | BUG_ON(offset >= PAGE_SIZE); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 431 | BUG_ON(npo->copy_off > MAX_BUFFER_OFFSET); |
| 432 | |
Ian Campbell | 6a8ed46 | 2012-10-10 03:48:42 +0000 | [diff] [blame] | 433 | bytes = PAGE_SIZE - offset; |
| 434 | |
| 435 | if (bytes > size) |
| 436 | bytes = size; |
| 437 | |
| 438 | if (start_new_rx_buffer(npo->copy_off, bytes, *head)) { |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 439 | /* |
| 440 | * Netfront requires there to be some data in the head |
| 441 | * buffer. |
| 442 | */ |
| 443 | BUG_ON(*head); |
| 444 | |
| 445 | meta = get_next_rx_buffer(vif, npo); |
| 446 | } |
| 447 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 448 | if (npo->copy_off + bytes > MAX_BUFFER_OFFSET) |
| 449 | bytes = MAX_BUFFER_OFFSET - npo->copy_off; |
| 450 | |
| 451 | copy_gop = npo->copy + npo->copy_prod++; |
| 452 | copy_gop->flags = GNTCOPY_dest_gref; |
| 453 | if (foreign) { |
| 454 | struct xen_netbk *netbk = &xen_netbk[group]; |
| 455 | struct pending_tx_info *src_pend; |
| 456 | |
| 457 | src_pend = &netbk->pending_tx_info[idx]; |
| 458 | |
| 459 | copy_gop->source.domid = src_pend->vif->domid; |
| 460 | copy_gop->source.u.ref = src_pend->req.gref; |
| 461 | copy_gop->flags |= GNTCOPY_source_gref; |
| 462 | } else { |
| 463 | void *vaddr = page_address(page); |
| 464 | copy_gop->source.domid = DOMID_SELF; |
| 465 | copy_gop->source.u.gmfn = virt_to_mfn(vaddr); |
| 466 | } |
| 467 | copy_gop->source.offset = offset; |
| 468 | copy_gop->dest.domid = vif->domid; |
| 469 | |
| 470 | copy_gop->dest.offset = npo->copy_off; |
| 471 | copy_gop->dest.u.ref = npo->copy_gref; |
| 472 | copy_gop->len = bytes; |
| 473 | |
| 474 | npo->copy_off += bytes; |
| 475 | meta->size += bytes; |
| 476 | |
| 477 | offset += bytes; |
| 478 | size -= bytes; |
| 479 | |
Ian Campbell | 6a8ed46 | 2012-10-10 03:48:42 +0000 | [diff] [blame] | 480 | /* Next frame */ |
| 481 | if (offset == PAGE_SIZE && size) { |
| 482 | BUG_ON(!PageCompound(page)); |
| 483 | page++; |
| 484 | offset = 0; |
| 485 | } |
| 486 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 487 | /* Leave a gap for the GSO descriptor. */ |
| 488 | if (*head && skb_shinfo(skb)->gso_size && !vif->gso_prefix) |
| 489 | vif->rx.req_cons++; |
| 490 | |
| 491 | *head = 0; /* There must be something in this buffer now. */ |
| 492 | |
| 493 | } |
| 494 | } |
| 495 | |
| 496 | /* |
| 497 | * Prepare an SKB to be transmitted to the frontend. |
| 498 | * |
| 499 | * This function is responsible for allocating grant operations, meta |
| 500 | * structures, etc. |
| 501 | * |
| 502 | * It returns the number of meta structures consumed. The number of |
| 503 | * ring slots used is always equal to the number of meta slots used |
| 504 | * plus the number of GSO descriptors used. Currently, we use either |
| 505 | * zero GSO descriptors (for non-GSO packets) or one descriptor (for |
| 506 | * frontend-side LRO). |
| 507 | */ |
| 508 | static int netbk_gop_skb(struct sk_buff *skb, |
| 509 | struct netrx_pending_operations *npo) |
| 510 | { |
| 511 | struct xenvif *vif = netdev_priv(skb->dev); |
| 512 | int nr_frags = skb_shinfo(skb)->nr_frags; |
| 513 | int i; |
| 514 | struct xen_netif_rx_request *req; |
| 515 | struct netbk_rx_meta *meta; |
| 516 | unsigned char *data; |
| 517 | int head = 1; |
| 518 | int old_meta_prod; |
| 519 | |
| 520 | old_meta_prod = npo->meta_prod; |
| 521 | |
| 522 | /* Set up a GSO prefix descriptor, if necessary */ |
| 523 | if (skb_shinfo(skb)->gso_size && vif->gso_prefix) { |
| 524 | req = RING_GET_REQUEST(&vif->rx, vif->rx.req_cons++); |
| 525 | meta = npo->meta + npo->meta_prod++; |
| 526 | meta->gso_size = skb_shinfo(skb)->gso_size; |
| 527 | meta->size = 0; |
| 528 | meta->id = req->id; |
| 529 | } |
| 530 | |
| 531 | req = RING_GET_REQUEST(&vif->rx, vif->rx.req_cons++); |
| 532 | meta = npo->meta + npo->meta_prod++; |
| 533 | |
| 534 | if (!vif->gso_prefix) |
| 535 | meta->gso_size = skb_shinfo(skb)->gso_size; |
| 536 | else |
| 537 | meta->gso_size = 0; |
| 538 | |
| 539 | meta->size = 0; |
| 540 | meta->id = req->id; |
| 541 | npo->copy_off = 0; |
| 542 | npo->copy_gref = req->gref; |
| 543 | |
| 544 | data = skb->data; |
| 545 | while (data < skb_tail_pointer(skb)) { |
| 546 | unsigned int offset = offset_in_page(data); |
| 547 | unsigned int len = PAGE_SIZE - offset; |
| 548 | |
| 549 | if (data + len > skb_tail_pointer(skb)) |
| 550 | len = skb_tail_pointer(skb) - data; |
| 551 | |
| 552 | netbk_gop_frag_copy(vif, skb, npo, |
| 553 | virt_to_page(data), len, offset, &head); |
| 554 | data += len; |
| 555 | } |
| 556 | |
| 557 | for (i = 0; i < nr_frags; i++) { |
| 558 | netbk_gop_frag_copy(vif, skb, npo, |
Ian Campbell | ea066ad | 2011-10-05 00:28:46 +0000 | [diff] [blame] | 559 | skb_frag_page(&skb_shinfo(skb)->frags[i]), |
Eric Dumazet | 9e903e0 | 2011-10-18 21:00:24 +0000 | [diff] [blame] | 560 | skb_frag_size(&skb_shinfo(skb)->frags[i]), |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 561 | skb_shinfo(skb)->frags[i].page_offset, |
| 562 | &head); |
| 563 | } |
| 564 | |
| 565 | return npo->meta_prod - old_meta_prod; |
| 566 | } |
| 567 | |
| 568 | /* |
| 569 | * This is a twin to netbk_gop_skb. Assume that netbk_gop_skb was |
| 570 | * used to set up the operations on the top of |
| 571 | * netrx_pending_operations, which have since been done. Check that |
| 572 | * they didn't give any errors and advance over them. |
| 573 | */ |
| 574 | static int netbk_check_gop(struct xenvif *vif, int nr_meta_slots, |
| 575 | struct netrx_pending_operations *npo) |
| 576 | { |
| 577 | struct gnttab_copy *copy_op; |
| 578 | int status = XEN_NETIF_RSP_OKAY; |
| 579 | int i; |
| 580 | |
| 581 | for (i = 0; i < nr_meta_slots; i++) { |
| 582 | copy_op = npo->copy + npo->copy_cons++; |
| 583 | if (copy_op->status != GNTST_okay) { |
| 584 | netdev_dbg(vif->dev, |
| 585 | "Bad status %d from copy to DOM%d.\n", |
| 586 | copy_op->status, vif->domid); |
| 587 | status = XEN_NETIF_RSP_ERROR; |
| 588 | } |
| 589 | } |
| 590 | |
| 591 | return status; |
| 592 | } |
| 593 | |
| 594 | static void netbk_add_frag_responses(struct xenvif *vif, int status, |
| 595 | struct netbk_rx_meta *meta, |
| 596 | int nr_meta_slots) |
| 597 | { |
| 598 | int i; |
| 599 | unsigned long offset; |
| 600 | |
| 601 | /* No fragments used */ |
| 602 | if (nr_meta_slots <= 1) |
| 603 | return; |
| 604 | |
| 605 | nr_meta_slots--; |
| 606 | |
| 607 | for (i = 0; i < nr_meta_slots; i++) { |
| 608 | int flags; |
| 609 | if (i == nr_meta_slots - 1) |
| 610 | flags = 0; |
| 611 | else |
| 612 | flags = XEN_NETRXF_more_data; |
| 613 | |
| 614 | offset = 0; |
| 615 | make_rx_response(vif, meta[i].id, status, offset, |
| 616 | meta[i].size, flags); |
| 617 | } |
| 618 | } |
| 619 | |
| 620 | struct skb_cb_overlay { |
| 621 | int meta_slots_used; |
| 622 | }; |
| 623 | |
| 624 | static void xen_netbk_rx_action(struct xen_netbk *netbk) |
| 625 | { |
| 626 | struct xenvif *vif = NULL, *tmp; |
| 627 | s8 status; |
| 628 | u16 irq, flags; |
| 629 | struct xen_netif_rx_response *resp; |
| 630 | struct sk_buff_head rxq; |
| 631 | struct sk_buff *skb; |
| 632 | LIST_HEAD(notify); |
| 633 | int ret; |
| 634 | int nr_frags; |
| 635 | int count; |
| 636 | unsigned long offset; |
| 637 | struct skb_cb_overlay *sco; |
| 638 | |
| 639 | struct netrx_pending_operations npo = { |
| 640 | .copy = netbk->grant_copy_op, |
| 641 | .meta = netbk->meta, |
| 642 | }; |
| 643 | |
| 644 | skb_queue_head_init(&rxq); |
| 645 | |
| 646 | count = 0; |
| 647 | |
| 648 | while ((skb = skb_dequeue(&netbk->rx_queue)) != NULL) { |
| 649 | vif = netdev_priv(skb->dev); |
| 650 | nr_frags = skb_shinfo(skb)->nr_frags; |
| 651 | |
| 652 | sco = (struct skb_cb_overlay *)skb->cb; |
| 653 | sco->meta_slots_used = netbk_gop_skb(skb, &npo); |
| 654 | |
| 655 | count += nr_frags + 1; |
| 656 | |
| 657 | __skb_queue_tail(&rxq, skb); |
| 658 | |
| 659 | /* Filled the batch queue? */ |
| 660 | if (count + MAX_SKB_FRAGS >= XEN_NETIF_RX_RING_SIZE) |
| 661 | break; |
| 662 | } |
| 663 | |
| 664 | BUG_ON(npo.meta_prod > ARRAY_SIZE(netbk->meta)); |
| 665 | |
| 666 | if (!npo.copy_prod) |
| 667 | return; |
| 668 | |
| 669 | BUG_ON(npo.copy_prod > ARRAY_SIZE(netbk->grant_copy_op)); |
Andres Lagar-Cavilla | c571898 | 2012-09-14 14:26:59 +0000 | [diff] [blame] | 670 | gnttab_batch_copy(netbk->grant_copy_op, npo.copy_prod); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 671 | |
| 672 | while ((skb = __skb_dequeue(&rxq)) != NULL) { |
| 673 | sco = (struct skb_cb_overlay *)skb->cb; |
| 674 | |
| 675 | vif = netdev_priv(skb->dev); |
| 676 | |
| 677 | if (netbk->meta[npo.meta_cons].gso_size && vif->gso_prefix) { |
| 678 | resp = RING_GET_RESPONSE(&vif->rx, |
| 679 | vif->rx.rsp_prod_pvt++); |
| 680 | |
| 681 | resp->flags = XEN_NETRXF_gso_prefix | XEN_NETRXF_more_data; |
| 682 | |
| 683 | resp->offset = netbk->meta[npo.meta_cons].gso_size; |
| 684 | resp->id = netbk->meta[npo.meta_cons].id; |
| 685 | resp->status = sco->meta_slots_used; |
| 686 | |
| 687 | npo.meta_cons++; |
| 688 | sco->meta_slots_used--; |
| 689 | } |
| 690 | |
| 691 | |
| 692 | vif->dev->stats.tx_bytes += skb->len; |
| 693 | vif->dev->stats.tx_packets++; |
| 694 | |
| 695 | status = netbk_check_gop(vif, sco->meta_slots_used, &npo); |
| 696 | |
| 697 | if (sco->meta_slots_used == 1) |
| 698 | flags = 0; |
| 699 | else |
| 700 | flags = XEN_NETRXF_more_data; |
| 701 | |
| 702 | if (skb->ip_summed == CHECKSUM_PARTIAL) /* local packet? */ |
| 703 | flags |= XEN_NETRXF_csum_blank | XEN_NETRXF_data_validated; |
| 704 | else if (skb->ip_summed == CHECKSUM_UNNECESSARY) |
| 705 | /* remote but checksummed. */ |
| 706 | flags |= XEN_NETRXF_data_validated; |
| 707 | |
| 708 | offset = 0; |
| 709 | resp = make_rx_response(vif, netbk->meta[npo.meta_cons].id, |
| 710 | status, offset, |
| 711 | netbk->meta[npo.meta_cons].size, |
| 712 | flags); |
| 713 | |
| 714 | if (netbk->meta[npo.meta_cons].gso_size && !vif->gso_prefix) { |
| 715 | struct xen_netif_extra_info *gso = |
| 716 | (struct xen_netif_extra_info *) |
| 717 | RING_GET_RESPONSE(&vif->rx, |
| 718 | vif->rx.rsp_prod_pvt++); |
| 719 | |
| 720 | resp->flags |= XEN_NETRXF_extra_info; |
| 721 | |
| 722 | gso->u.gso.size = netbk->meta[npo.meta_cons].gso_size; |
| 723 | gso->u.gso.type = XEN_NETIF_GSO_TYPE_TCPV4; |
| 724 | gso->u.gso.pad = 0; |
| 725 | gso->u.gso.features = 0; |
| 726 | |
| 727 | gso->type = XEN_NETIF_EXTRA_TYPE_GSO; |
| 728 | gso->flags = 0; |
| 729 | } |
| 730 | |
| 731 | netbk_add_frag_responses(vif, status, |
| 732 | netbk->meta + npo.meta_cons + 1, |
| 733 | sco->meta_slots_used); |
| 734 | |
| 735 | RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&vif->rx, ret); |
| 736 | irq = vif->irq; |
| 737 | if (ret && list_empty(&vif->notify_list)) |
| 738 | list_add_tail(&vif->notify_list, ¬ify); |
| 739 | |
| 740 | xenvif_notify_tx_completion(vif); |
| 741 | |
| 742 | xenvif_put(vif); |
| 743 | npo.meta_cons += sco->meta_slots_used; |
| 744 | dev_kfree_skb(skb); |
| 745 | } |
| 746 | |
| 747 | list_for_each_entry_safe(vif, tmp, ¬ify, notify_list) { |
| 748 | notify_remote_via_irq(vif->irq); |
| 749 | list_del_init(&vif->notify_list); |
| 750 | } |
| 751 | |
| 752 | /* More work to do? */ |
| 753 | if (!skb_queue_empty(&netbk->rx_queue) && |
| 754 | !timer_pending(&netbk->net_timer)) |
| 755 | xen_netbk_kick_thread(netbk); |
| 756 | } |
| 757 | |
| 758 | void xen_netbk_queue_tx_skb(struct xenvif *vif, struct sk_buff *skb) |
| 759 | { |
| 760 | struct xen_netbk *netbk = vif->netbk; |
| 761 | |
| 762 | skb_queue_tail(&netbk->rx_queue, skb); |
| 763 | |
| 764 | xen_netbk_kick_thread(netbk); |
| 765 | } |
| 766 | |
| 767 | static void xen_netbk_alarm(unsigned long data) |
| 768 | { |
| 769 | struct xen_netbk *netbk = (struct xen_netbk *)data; |
| 770 | xen_netbk_kick_thread(netbk); |
| 771 | } |
| 772 | |
| 773 | static int __on_net_schedule_list(struct xenvif *vif) |
| 774 | { |
| 775 | return !list_empty(&vif->schedule_list); |
| 776 | } |
| 777 | |
| 778 | /* Must be called with net_schedule_list_lock held */ |
| 779 | static void remove_from_net_schedule_list(struct xenvif *vif) |
| 780 | { |
| 781 | if (likely(__on_net_schedule_list(vif))) { |
| 782 | list_del_init(&vif->schedule_list); |
| 783 | xenvif_put(vif); |
| 784 | } |
| 785 | } |
| 786 | |
| 787 | static struct xenvif *poll_net_schedule_list(struct xen_netbk *netbk) |
| 788 | { |
| 789 | struct xenvif *vif = NULL; |
| 790 | |
| 791 | spin_lock_irq(&netbk->net_schedule_list_lock); |
| 792 | if (list_empty(&netbk->net_schedule_list)) |
| 793 | goto out; |
| 794 | |
| 795 | vif = list_first_entry(&netbk->net_schedule_list, |
| 796 | struct xenvif, schedule_list); |
| 797 | if (!vif) |
| 798 | goto out; |
| 799 | |
| 800 | xenvif_get(vif); |
| 801 | |
| 802 | remove_from_net_schedule_list(vif); |
| 803 | out: |
| 804 | spin_unlock_irq(&netbk->net_schedule_list_lock); |
| 805 | return vif; |
| 806 | } |
| 807 | |
| 808 | void xen_netbk_schedule_xenvif(struct xenvif *vif) |
| 809 | { |
| 810 | unsigned long flags; |
| 811 | struct xen_netbk *netbk = vif->netbk; |
| 812 | |
| 813 | if (__on_net_schedule_list(vif)) |
| 814 | goto kick; |
| 815 | |
| 816 | spin_lock_irqsave(&netbk->net_schedule_list_lock, flags); |
| 817 | if (!__on_net_schedule_list(vif) && |
| 818 | likely(xenvif_schedulable(vif))) { |
| 819 | list_add_tail(&vif->schedule_list, &netbk->net_schedule_list); |
| 820 | xenvif_get(vif); |
| 821 | } |
| 822 | spin_unlock_irqrestore(&netbk->net_schedule_list_lock, flags); |
| 823 | |
| 824 | kick: |
| 825 | smp_mb(); |
| 826 | if ((nr_pending_reqs(netbk) < (MAX_PENDING_REQS/2)) && |
| 827 | !list_empty(&netbk->net_schedule_list)) |
| 828 | xen_netbk_kick_thread(netbk); |
| 829 | } |
| 830 | |
| 831 | void xen_netbk_deschedule_xenvif(struct xenvif *vif) |
| 832 | { |
| 833 | struct xen_netbk *netbk = vif->netbk; |
| 834 | spin_lock_irq(&netbk->net_schedule_list_lock); |
| 835 | remove_from_net_schedule_list(vif); |
| 836 | spin_unlock_irq(&netbk->net_schedule_list_lock); |
| 837 | } |
| 838 | |
| 839 | void xen_netbk_check_rx_xenvif(struct xenvif *vif) |
| 840 | { |
| 841 | int more_to_do; |
| 842 | |
| 843 | RING_FINAL_CHECK_FOR_REQUESTS(&vif->tx, more_to_do); |
| 844 | |
| 845 | if (more_to_do) |
| 846 | xen_netbk_schedule_xenvif(vif); |
| 847 | } |
| 848 | |
| 849 | static void tx_add_credit(struct xenvif *vif) |
| 850 | { |
| 851 | unsigned long max_burst, max_credit; |
| 852 | |
| 853 | /* |
| 854 | * Allow a burst big enough to transmit a jumbo packet of up to 128kB. |
| 855 | * Otherwise the interface can seize up due to insufficient credit. |
| 856 | */ |
| 857 | max_burst = RING_GET_REQUEST(&vif->tx, vif->tx.req_cons)->size; |
| 858 | max_burst = min(max_burst, 131072UL); |
| 859 | max_burst = max(max_burst, vif->credit_bytes); |
| 860 | |
| 861 | /* Take care that adding a new chunk of credit doesn't wrap to zero. */ |
| 862 | max_credit = vif->remaining_credit + vif->credit_bytes; |
| 863 | if (max_credit < vif->remaining_credit) |
| 864 | max_credit = ULONG_MAX; /* wrapped: clamp to ULONG_MAX */ |
| 865 | |
| 866 | vif->remaining_credit = min(max_credit, max_burst); |
| 867 | } |
| 868 | |
| 869 | static void tx_credit_callback(unsigned long data) |
| 870 | { |
| 871 | struct xenvif *vif = (struct xenvif *)data; |
| 872 | tx_add_credit(vif); |
| 873 | xen_netbk_check_rx_xenvif(vif); |
| 874 | } |
| 875 | |
| 876 | static void netbk_tx_err(struct xenvif *vif, |
| 877 | struct xen_netif_tx_request *txp, RING_IDX end) |
| 878 | { |
| 879 | RING_IDX cons = vif->tx.req_cons; |
| 880 | |
| 881 | do { |
| 882 | make_tx_response(vif, txp, XEN_NETIF_RSP_ERROR); |
Ian Campbell | b914972 | 2013-02-06 23:41:38 +0000 | [diff] [blame] | 883 | if (cons == end) |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 884 | break; |
| 885 | txp = RING_GET_REQUEST(&vif->tx, cons++); |
| 886 | } while (1); |
| 887 | vif->tx.req_cons = cons; |
| 888 | xen_netbk_check_rx_xenvif(vif); |
| 889 | xenvif_put(vif); |
| 890 | } |
| 891 | |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 892 | static void netbk_fatal_tx_err(struct xenvif *vif) |
| 893 | { |
| 894 | netdev_err(vif->dev, "fatal error; disabling device\n"); |
| 895 | xenvif_carrier_off(vif); |
David S. Miller | 629821d | 2013-02-19 13:04:34 -0500 | [diff] [blame] | 896 | xenvif_put(vif); |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 897 | } |
| 898 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 899 | static int netbk_count_requests(struct xenvif *vif, |
| 900 | struct xen_netif_tx_request *first, |
| 901 | struct xen_netif_tx_request *txp, |
| 902 | int work_to_do) |
| 903 | { |
| 904 | RING_IDX cons = vif->tx.req_cons; |
| 905 | int frags = 0; |
| 906 | |
| 907 | if (!(first->flags & XEN_NETTXF_more_data)) |
| 908 | return 0; |
| 909 | |
| 910 | do { |
| 911 | if (frags >= work_to_do) { |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 912 | netdev_err(vif->dev, "Need more frags\n"); |
| 913 | netbk_fatal_tx_err(vif); |
David Vrabel | 35876b5 | 2013-02-14 03:18:57 +0000 | [diff] [blame] | 914 | return -ENODATA; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 915 | } |
| 916 | |
| 917 | if (unlikely(frags >= MAX_SKB_FRAGS)) { |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 918 | netdev_err(vif->dev, "Too many frags\n"); |
| 919 | netbk_fatal_tx_err(vif); |
David Vrabel | 35876b5 | 2013-02-14 03:18:57 +0000 | [diff] [blame] | 920 | return -E2BIG; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 921 | } |
| 922 | |
| 923 | memcpy(txp, RING_GET_REQUEST(&vif->tx, cons + frags), |
| 924 | sizeof(*txp)); |
| 925 | if (txp->size > first->size) { |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 926 | netdev_err(vif->dev, "Frag is bigger than frame.\n"); |
| 927 | netbk_fatal_tx_err(vif); |
David Vrabel | 35876b5 | 2013-02-14 03:18:57 +0000 | [diff] [blame] | 928 | return -EIO; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 929 | } |
| 930 | |
| 931 | first->size -= txp->size; |
| 932 | frags++; |
| 933 | |
| 934 | if (unlikely((txp->offset + txp->size) > PAGE_SIZE)) { |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 935 | netdev_err(vif->dev, "txp->offset: %x, size: %u\n", |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 936 | txp->offset, txp->size); |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 937 | netbk_fatal_tx_err(vif); |
David Vrabel | 35876b5 | 2013-02-14 03:18:57 +0000 | [diff] [blame] | 938 | return -EINVAL; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 939 | } |
| 940 | } while ((txp++)->flags & XEN_NETTXF_more_data); |
| 941 | return frags; |
| 942 | } |
| 943 | |
| 944 | static struct page *xen_netbk_alloc_page(struct xen_netbk *netbk, |
| 945 | struct sk_buff *skb, |
Ian Campbell | ea066ad | 2011-10-05 00:28:46 +0000 | [diff] [blame] | 946 | u16 pending_idx) |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 947 | { |
| 948 | struct page *page; |
| 949 | page = alloc_page(GFP_KERNEL|__GFP_COLD); |
| 950 | if (!page) |
| 951 | return NULL; |
| 952 | set_page_ext(page, netbk, pending_idx); |
| 953 | netbk->mmap_pages[pending_idx] = page; |
| 954 | return page; |
| 955 | } |
| 956 | |
| 957 | static struct gnttab_copy *xen_netbk_get_requests(struct xen_netbk *netbk, |
| 958 | struct xenvif *vif, |
| 959 | struct sk_buff *skb, |
| 960 | struct xen_netif_tx_request *txp, |
| 961 | struct gnttab_copy *gop) |
| 962 | { |
| 963 | struct skb_shared_info *shinfo = skb_shinfo(skb); |
| 964 | skb_frag_t *frags = shinfo->frags; |
Ian Campbell | ea066ad | 2011-10-05 00:28:46 +0000 | [diff] [blame] | 965 | u16 pending_idx = *((u16 *)skb->data); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 966 | int i, start; |
| 967 | |
| 968 | /* Skip first skb fragment if it is on same page as header fragment. */ |
Ian Campbell | ea066ad | 2011-10-05 00:28:46 +0000 | [diff] [blame] | 969 | start = (frag_get_pending_idx(&shinfo->frags[0]) == pending_idx); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 970 | |
| 971 | for (i = start; i < shinfo->nr_frags; i++, txp++) { |
| 972 | struct page *page; |
| 973 | pending_ring_idx_t index; |
| 974 | struct pending_tx_info *pending_tx_info = |
| 975 | netbk->pending_tx_info; |
| 976 | |
| 977 | index = pending_index(netbk->pending_cons++); |
| 978 | pending_idx = netbk->pending_ring[index]; |
| 979 | page = xen_netbk_alloc_page(netbk, skb, pending_idx); |
| 980 | if (!page) |
Ian Campbell | 4cc7c1c | 2013-02-06 23:41:37 +0000 | [diff] [blame] | 981 | goto err; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 982 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 983 | gop->source.u.ref = txp->gref; |
| 984 | gop->source.domid = vif->domid; |
| 985 | gop->source.offset = txp->offset; |
| 986 | |
| 987 | gop->dest.u.gmfn = virt_to_mfn(page_address(page)); |
| 988 | gop->dest.domid = DOMID_SELF; |
| 989 | gop->dest.offset = txp->offset; |
| 990 | |
| 991 | gop->len = txp->size; |
| 992 | gop->flags = GNTCOPY_source_gref; |
| 993 | |
| 994 | gop++; |
| 995 | |
| 996 | memcpy(&pending_tx_info[pending_idx].req, txp, sizeof(*txp)); |
| 997 | xenvif_get(vif); |
| 998 | pending_tx_info[pending_idx].vif = vif; |
Ian Campbell | ea066ad | 2011-10-05 00:28:46 +0000 | [diff] [blame] | 999 | frag_set_pending_idx(&frags[i], pending_idx); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1000 | } |
| 1001 | |
| 1002 | return gop; |
Ian Campbell | 4cc7c1c | 2013-02-06 23:41:37 +0000 | [diff] [blame] | 1003 | err: |
| 1004 | /* Unwind, freeing all pages and sending error responses. */ |
| 1005 | while (i-- > start) { |
| 1006 | xen_netbk_idx_release(netbk, frag_get_pending_idx(&frags[i]), |
| 1007 | XEN_NETIF_RSP_ERROR); |
| 1008 | } |
| 1009 | /* The head too, if necessary. */ |
| 1010 | if (start) |
| 1011 | xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_ERROR); |
| 1012 | |
| 1013 | return NULL; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1014 | } |
| 1015 | |
| 1016 | static int xen_netbk_tx_check_gop(struct xen_netbk *netbk, |
| 1017 | struct sk_buff *skb, |
| 1018 | struct gnttab_copy **gopp) |
| 1019 | { |
| 1020 | struct gnttab_copy *gop = *gopp; |
Ian Campbell | ea066ad | 2011-10-05 00:28:46 +0000 | [diff] [blame] | 1021 | u16 pending_idx = *((u16 *)skb->data); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1022 | struct skb_shared_info *shinfo = skb_shinfo(skb); |
| 1023 | int nr_frags = shinfo->nr_frags; |
| 1024 | int i, err, start; |
| 1025 | |
| 1026 | /* Check status of header. */ |
| 1027 | err = gop->status; |
Matthew Daley | 7d5145d | 2013-02-06 23:41:36 +0000 | [diff] [blame] | 1028 | if (unlikely(err)) |
| 1029 | xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_ERROR); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1030 | |
| 1031 | /* Skip first skb fragment if it is on same page as header fragment. */ |
Ian Campbell | ea066ad | 2011-10-05 00:28:46 +0000 | [diff] [blame] | 1032 | start = (frag_get_pending_idx(&shinfo->frags[0]) == pending_idx); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1033 | |
| 1034 | for (i = start; i < nr_frags; i++) { |
| 1035 | int j, newerr; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1036 | |
Ian Campbell | ea066ad | 2011-10-05 00:28:46 +0000 | [diff] [blame] | 1037 | pending_idx = frag_get_pending_idx(&shinfo->frags[i]); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1038 | |
| 1039 | /* Check error status: if okay then remember grant handle. */ |
| 1040 | newerr = (++gop)->status; |
| 1041 | if (likely(!newerr)) { |
| 1042 | /* Had a previous error? Invalidate this fragment. */ |
| 1043 | if (unlikely(err)) |
Matthew Daley | 7d5145d | 2013-02-06 23:41:36 +0000 | [diff] [blame] | 1044 | xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_OKAY); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1045 | continue; |
| 1046 | } |
| 1047 | |
| 1048 | /* Error on this fragment: respond to client with an error. */ |
Matthew Daley | 7d5145d | 2013-02-06 23:41:36 +0000 | [diff] [blame] | 1049 | xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_ERROR); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1050 | |
| 1051 | /* Not the first error? Preceding frags already invalidated. */ |
| 1052 | if (err) |
| 1053 | continue; |
| 1054 | |
| 1055 | /* First error: invalidate header and preceding fragments. */ |
| 1056 | pending_idx = *((u16 *)skb->data); |
Matthew Daley | 7d5145d | 2013-02-06 23:41:36 +0000 | [diff] [blame] | 1057 | xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_OKAY); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1058 | for (j = start; j < i; j++) { |
Jan Beulich | 5ccb3ea | 2011-11-18 05:42:05 +0000 | [diff] [blame] | 1059 | pending_idx = frag_get_pending_idx(&shinfo->frags[j]); |
Matthew Daley | 7d5145d | 2013-02-06 23:41:36 +0000 | [diff] [blame] | 1060 | xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_OKAY); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1061 | } |
| 1062 | |
| 1063 | /* Remember the error: invalidate all subsequent fragments. */ |
| 1064 | err = newerr; |
| 1065 | } |
| 1066 | |
| 1067 | *gopp = gop + 1; |
| 1068 | return err; |
| 1069 | } |
| 1070 | |
| 1071 | static void xen_netbk_fill_frags(struct xen_netbk *netbk, struct sk_buff *skb) |
| 1072 | { |
| 1073 | struct skb_shared_info *shinfo = skb_shinfo(skb); |
| 1074 | int nr_frags = shinfo->nr_frags; |
| 1075 | int i; |
| 1076 | |
| 1077 | for (i = 0; i < nr_frags; i++) { |
| 1078 | skb_frag_t *frag = shinfo->frags + i; |
| 1079 | struct xen_netif_tx_request *txp; |
Ian Campbell | ea066ad | 2011-10-05 00:28:46 +0000 | [diff] [blame] | 1080 | struct page *page; |
| 1081 | u16 pending_idx; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1082 | |
Ian Campbell | ea066ad | 2011-10-05 00:28:46 +0000 | [diff] [blame] | 1083 | pending_idx = frag_get_pending_idx(frag); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1084 | |
| 1085 | txp = &netbk->pending_tx_info[pending_idx].req; |
Ian Campbell | ea066ad | 2011-10-05 00:28:46 +0000 | [diff] [blame] | 1086 | page = virt_to_page(idx_to_kaddr(netbk, pending_idx)); |
| 1087 | __skb_fill_page_desc(skb, i, page, txp->offset, txp->size); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1088 | skb->len += txp->size; |
| 1089 | skb->data_len += txp->size; |
| 1090 | skb->truesize += txp->size; |
| 1091 | |
| 1092 | /* Take an extra reference to offset xen_netbk_idx_release */ |
| 1093 | get_page(netbk->mmap_pages[pending_idx]); |
Matthew Daley | 7d5145d | 2013-02-06 23:41:36 +0000 | [diff] [blame] | 1094 | xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_OKAY); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1095 | } |
| 1096 | } |
| 1097 | |
| 1098 | static int xen_netbk_get_extras(struct xenvif *vif, |
| 1099 | struct xen_netif_extra_info *extras, |
| 1100 | int work_to_do) |
| 1101 | { |
| 1102 | struct xen_netif_extra_info extra; |
| 1103 | RING_IDX cons = vif->tx.req_cons; |
| 1104 | |
| 1105 | do { |
| 1106 | if (unlikely(work_to_do-- <= 0)) { |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 1107 | netdev_err(vif->dev, "Missing extra info\n"); |
| 1108 | netbk_fatal_tx_err(vif); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1109 | return -EBADR; |
| 1110 | } |
| 1111 | |
| 1112 | memcpy(&extra, RING_GET_REQUEST(&vif->tx, cons), |
| 1113 | sizeof(extra)); |
| 1114 | if (unlikely(!extra.type || |
| 1115 | extra.type >= XEN_NETIF_EXTRA_TYPE_MAX)) { |
| 1116 | vif->tx.req_cons = ++cons; |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 1117 | netdev_err(vif->dev, |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1118 | "Invalid extra type: %d\n", extra.type); |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 1119 | netbk_fatal_tx_err(vif); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1120 | return -EINVAL; |
| 1121 | } |
| 1122 | |
| 1123 | memcpy(&extras[extra.type - 1], &extra, sizeof(extra)); |
| 1124 | vif->tx.req_cons = ++cons; |
| 1125 | } while (extra.flags & XEN_NETIF_EXTRA_FLAG_MORE); |
| 1126 | |
| 1127 | return work_to_do; |
| 1128 | } |
| 1129 | |
| 1130 | static int netbk_set_skb_gso(struct xenvif *vif, |
| 1131 | struct sk_buff *skb, |
| 1132 | struct xen_netif_extra_info *gso) |
| 1133 | { |
| 1134 | if (!gso->u.gso.size) { |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 1135 | netdev_err(vif->dev, "GSO size must not be zero.\n"); |
| 1136 | netbk_fatal_tx_err(vif); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1137 | return -EINVAL; |
| 1138 | } |
| 1139 | |
| 1140 | /* Currently only TCPv4 S.O. is supported. */ |
| 1141 | if (gso->u.gso.type != XEN_NETIF_GSO_TYPE_TCPV4) { |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 1142 | netdev_err(vif->dev, "Bad GSO type %d.\n", gso->u.gso.type); |
| 1143 | netbk_fatal_tx_err(vif); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1144 | return -EINVAL; |
| 1145 | } |
| 1146 | |
| 1147 | skb_shinfo(skb)->gso_size = gso->u.gso.size; |
| 1148 | skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4; |
| 1149 | |
| 1150 | /* Header must be checked, and gso_segs computed. */ |
| 1151 | skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; |
| 1152 | skb_shinfo(skb)->gso_segs = 0; |
| 1153 | |
| 1154 | return 0; |
| 1155 | } |
| 1156 | |
| 1157 | static int checksum_setup(struct xenvif *vif, struct sk_buff *skb) |
| 1158 | { |
| 1159 | struct iphdr *iph; |
| 1160 | unsigned char *th; |
| 1161 | int err = -EPROTO; |
| 1162 | int recalculate_partial_csum = 0; |
| 1163 | |
| 1164 | /* |
| 1165 | * A GSO SKB must be CHECKSUM_PARTIAL. However some buggy |
| 1166 | * peers can fail to set NETRXF_csum_blank when sending a GSO |
| 1167 | * frame. In this case force the SKB to CHECKSUM_PARTIAL and |
| 1168 | * recalculate the partial checksum. |
| 1169 | */ |
| 1170 | if (skb->ip_summed != CHECKSUM_PARTIAL && skb_is_gso(skb)) { |
| 1171 | vif->rx_gso_checksum_fixup++; |
| 1172 | skb->ip_summed = CHECKSUM_PARTIAL; |
| 1173 | recalculate_partial_csum = 1; |
| 1174 | } |
| 1175 | |
| 1176 | /* A non-CHECKSUM_PARTIAL SKB does not require setup. */ |
| 1177 | if (skb->ip_summed != CHECKSUM_PARTIAL) |
| 1178 | return 0; |
| 1179 | |
| 1180 | if (skb->protocol != htons(ETH_P_IP)) |
| 1181 | goto out; |
| 1182 | |
| 1183 | iph = (void *)skb->data; |
| 1184 | th = skb->data + 4 * iph->ihl; |
| 1185 | if (th >= skb_tail_pointer(skb)) |
| 1186 | goto out; |
| 1187 | |
| 1188 | skb->csum_start = th - skb->head; |
| 1189 | switch (iph->protocol) { |
| 1190 | case IPPROTO_TCP: |
| 1191 | skb->csum_offset = offsetof(struct tcphdr, check); |
| 1192 | |
| 1193 | if (recalculate_partial_csum) { |
| 1194 | struct tcphdr *tcph = (struct tcphdr *)th; |
| 1195 | tcph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, |
| 1196 | skb->len - iph->ihl*4, |
| 1197 | IPPROTO_TCP, 0); |
| 1198 | } |
| 1199 | break; |
| 1200 | case IPPROTO_UDP: |
| 1201 | skb->csum_offset = offsetof(struct udphdr, check); |
| 1202 | |
| 1203 | if (recalculate_partial_csum) { |
| 1204 | struct udphdr *udph = (struct udphdr *)th; |
| 1205 | udph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, |
| 1206 | skb->len - iph->ihl*4, |
| 1207 | IPPROTO_UDP, 0); |
| 1208 | } |
| 1209 | break; |
| 1210 | default: |
| 1211 | if (net_ratelimit()) |
| 1212 | netdev_err(vif->dev, |
| 1213 | "Attempting to checksum a non-TCP/UDP packet, dropping a protocol %d packet\n", |
| 1214 | iph->protocol); |
| 1215 | goto out; |
| 1216 | } |
| 1217 | |
| 1218 | if ((th + skb->csum_offset + 2) > skb_tail_pointer(skb)) |
| 1219 | goto out; |
| 1220 | |
| 1221 | err = 0; |
| 1222 | |
| 1223 | out: |
| 1224 | return err; |
| 1225 | } |
| 1226 | |
| 1227 | static bool tx_credit_exceeded(struct xenvif *vif, unsigned size) |
| 1228 | { |
| 1229 | unsigned long now = jiffies; |
| 1230 | unsigned long next_credit = |
| 1231 | vif->credit_timeout.expires + |
| 1232 | msecs_to_jiffies(vif->credit_usec / 1000); |
| 1233 | |
| 1234 | /* Timer could already be pending in rare cases. */ |
| 1235 | if (timer_pending(&vif->credit_timeout)) |
| 1236 | return true; |
| 1237 | |
| 1238 | /* Passed the point where we can replenish credit? */ |
| 1239 | if (time_after_eq(now, next_credit)) { |
| 1240 | vif->credit_timeout.expires = now; |
| 1241 | tx_add_credit(vif); |
| 1242 | } |
| 1243 | |
| 1244 | /* Still too big to send right now? Set a callback. */ |
| 1245 | if (size > vif->remaining_credit) { |
| 1246 | vif->credit_timeout.data = |
| 1247 | (unsigned long)vif; |
| 1248 | vif->credit_timeout.function = |
| 1249 | tx_credit_callback; |
| 1250 | mod_timer(&vif->credit_timeout, |
| 1251 | next_credit); |
| 1252 | |
| 1253 | return true; |
| 1254 | } |
| 1255 | |
| 1256 | return false; |
| 1257 | } |
| 1258 | |
| 1259 | static unsigned xen_netbk_tx_build_gops(struct xen_netbk *netbk) |
| 1260 | { |
| 1261 | struct gnttab_copy *gop = netbk->tx_copy_ops, *request_gop; |
| 1262 | struct sk_buff *skb; |
| 1263 | int ret; |
| 1264 | |
| 1265 | while (((nr_pending_reqs(netbk) + MAX_SKB_FRAGS) < MAX_PENDING_REQS) && |
| 1266 | !list_empty(&netbk->net_schedule_list)) { |
| 1267 | struct xenvif *vif; |
| 1268 | struct xen_netif_tx_request txreq; |
| 1269 | struct xen_netif_tx_request txfrags[MAX_SKB_FRAGS]; |
| 1270 | struct page *page; |
| 1271 | struct xen_netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX-1]; |
| 1272 | u16 pending_idx; |
| 1273 | RING_IDX idx; |
| 1274 | int work_to_do; |
| 1275 | unsigned int data_len; |
| 1276 | pending_ring_idx_t index; |
| 1277 | |
| 1278 | /* Get a netif from the list with work to do. */ |
| 1279 | vif = poll_net_schedule_list(netbk); |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 1280 | /* This can sometimes happen because the test of |
| 1281 | * list_empty(net_schedule_list) at the top of the |
| 1282 | * loop is unlocked. Just go back and have another |
| 1283 | * look. |
| 1284 | */ |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1285 | if (!vif) |
| 1286 | continue; |
| 1287 | |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 1288 | if (vif->tx.sring->req_prod - vif->tx.req_cons > |
| 1289 | XEN_NETIF_TX_RING_SIZE) { |
| 1290 | netdev_err(vif->dev, |
| 1291 | "Impossible number of requests. " |
| 1292 | "req_prod %d, req_cons %d, size %ld\n", |
| 1293 | vif->tx.sring->req_prod, vif->tx.req_cons, |
| 1294 | XEN_NETIF_TX_RING_SIZE); |
| 1295 | netbk_fatal_tx_err(vif); |
| 1296 | continue; |
| 1297 | } |
| 1298 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1299 | RING_FINAL_CHECK_FOR_REQUESTS(&vif->tx, work_to_do); |
| 1300 | if (!work_to_do) { |
| 1301 | xenvif_put(vif); |
| 1302 | continue; |
| 1303 | } |
| 1304 | |
| 1305 | idx = vif->tx.req_cons; |
| 1306 | rmb(); /* Ensure that we see the request before we copy it. */ |
| 1307 | memcpy(&txreq, RING_GET_REQUEST(&vif->tx, idx), sizeof(txreq)); |
| 1308 | |
| 1309 | /* Credit-based scheduling. */ |
| 1310 | if (txreq.size > vif->remaining_credit && |
| 1311 | tx_credit_exceeded(vif, txreq.size)) { |
| 1312 | xenvif_put(vif); |
| 1313 | continue; |
| 1314 | } |
| 1315 | |
| 1316 | vif->remaining_credit -= txreq.size; |
| 1317 | |
| 1318 | work_to_do--; |
| 1319 | vif->tx.req_cons = ++idx; |
| 1320 | |
| 1321 | memset(extras, 0, sizeof(extras)); |
| 1322 | if (txreq.flags & XEN_NETTXF_extra_info) { |
| 1323 | work_to_do = xen_netbk_get_extras(vif, extras, |
| 1324 | work_to_do); |
| 1325 | idx = vif->tx.req_cons; |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 1326 | if (unlikely(work_to_do < 0)) |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1327 | continue; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1328 | } |
| 1329 | |
| 1330 | ret = netbk_count_requests(vif, &txreq, txfrags, work_to_do); |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 1331 | if (unlikely(ret < 0)) |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1332 | continue; |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 1333 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1334 | idx += ret; |
| 1335 | |
| 1336 | if (unlikely(txreq.size < ETH_HLEN)) { |
| 1337 | netdev_dbg(vif->dev, |
| 1338 | "Bad packet size: %d\n", txreq.size); |
| 1339 | netbk_tx_err(vif, &txreq, idx); |
| 1340 | continue; |
| 1341 | } |
| 1342 | |
| 1343 | /* No crossing a page as the payload mustn't fragment. */ |
| 1344 | if (unlikely((txreq.offset + txreq.size) > PAGE_SIZE)) { |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 1345 | netdev_err(vif->dev, |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1346 | "txreq.offset: %x, size: %u, end: %lu\n", |
| 1347 | txreq.offset, txreq.size, |
| 1348 | (txreq.offset&~PAGE_MASK) + txreq.size); |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 1349 | netbk_fatal_tx_err(vif); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1350 | continue; |
| 1351 | } |
| 1352 | |
| 1353 | index = pending_index(netbk->pending_cons); |
| 1354 | pending_idx = netbk->pending_ring[index]; |
| 1355 | |
| 1356 | data_len = (txreq.size > PKT_PROT_LEN && |
| 1357 | ret < MAX_SKB_FRAGS) ? |
| 1358 | PKT_PROT_LEN : txreq.size; |
| 1359 | |
| 1360 | skb = alloc_skb(data_len + NET_SKB_PAD + NET_IP_ALIGN, |
| 1361 | GFP_ATOMIC | __GFP_NOWARN); |
| 1362 | if (unlikely(skb == NULL)) { |
| 1363 | netdev_dbg(vif->dev, |
| 1364 | "Can't allocate a skb in start_xmit.\n"); |
| 1365 | netbk_tx_err(vif, &txreq, idx); |
| 1366 | break; |
| 1367 | } |
| 1368 | |
| 1369 | /* Packets passed to netif_rx() must have some headroom. */ |
| 1370 | skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN); |
| 1371 | |
| 1372 | if (extras[XEN_NETIF_EXTRA_TYPE_GSO - 1].type) { |
| 1373 | struct xen_netif_extra_info *gso; |
| 1374 | gso = &extras[XEN_NETIF_EXTRA_TYPE_GSO - 1]; |
| 1375 | |
| 1376 | if (netbk_set_skb_gso(vif, skb, gso)) { |
Ian Campbell | 48856286 | 2013-02-06 23:41:35 +0000 | [diff] [blame] | 1377 | /* Failure in netbk_set_skb_gso is fatal. */ |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1378 | kfree_skb(skb); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1379 | continue; |
| 1380 | } |
| 1381 | } |
| 1382 | |
| 1383 | /* XXX could copy straight to head */ |
| 1384 | page = xen_netbk_alloc_page(netbk, skb, pending_idx); |
| 1385 | if (!page) { |
| 1386 | kfree_skb(skb); |
| 1387 | netbk_tx_err(vif, &txreq, idx); |
| 1388 | continue; |
| 1389 | } |
| 1390 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1391 | gop->source.u.ref = txreq.gref; |
| 1392 | gop->source.domid = vif->domid; |
| 1393 | gop->source.offset = txreq.offset; |
| 1394 | |
| 1395 | gop->dest.u.gmfn = virt_to_mfn(page_address(page)); |
| 1396 | gop->dest.domid = DOMID_SELF; |
| 1397 | gop->dest.offset = txreq.offset; |
| 1398 | |
| 1399 | gop->len = txreq.size; |
| 1400 | gop->flags = GNTCOPY_source_gref; |
| 1401 | |
| 1402 | gop++; |
| 1403 | |
| 1404 | memcpy(&netbk->pending_tx_info[pending_idx].req, |
| 1405 | &txreq, sizeof(txreq)); |
| 1406 | netbk->pending_tx_info[pending_idx].vif = vif; |
| 1407 | *((u16 *)skb->data) = pending_idx; |
| 1408 | |
| 1409 | __skb_put(skb, data_len); |
| 1410 | |
| 1411 | skb_shinfo(skb)->nr_frags = ret; |
| 1412 | if (data_len < txreq.size) { |
| 1413 | skb_shinfo(skb)->nr_frags++; |
Ian Campbell | ea066ad | 2011-10-05 00:28:46 +0000 | [diff] [blame] | 1414 | frag_set_pending_idx(&skb_shinfo(skb)->frags[0], |
| 1415 | pending_idx); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1416 | } else { |
Ian Campbell | ea066ad | 2011-10-05 00:28:46 +0000 | [diff] [blame] | 1417 | frag_set_pending_idx(&skb_shinfo(skb)->frags[0], |
| 1418 | INVALID_PENDING_IDX); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1419 | } |
| 1420 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1421 | netbk->pending_cons++; |
| 1422 | |
| 1423 | request_gop = xen_netbk_get_requests(netbk, vif, |
| 1424 | skb, txfrags, gop); |
| 1425 | if (request_gop == NULL) { |
| 1426 | kfree_skb(skb); |
| 1427 | netbk_tx_err(vif, &txreq, idx); |
| 1428 | continue; |
| 1429 | } |
| 1430 | gop = request_gop; |
| 1431 | |
Annie Li | 1e0b6ea | 2012-06-27 00:46:58 +0000 | [diff] [blame] | 1432 | __skb_queue_tail(&netbk->tx_queue, skb); |
| 1433 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1434 | vif->tx.req_cons = idx; |
| 1435 | xen_netbk_check_rx_xenvif(vif); |
| 1436 | |
| 1437 | if ((gop-netbk->tx_copy_ops) >= ARRAY_SIZE(netbk->tx_copy_ops)) |
| 1438 | break; |
| 1439 | } |
| 1440 | |
| 1441 | return gop - netbk->tx_copy_ops; |
| 1442 | } |
| 1443 | |
| 1444 | static void xen_netbk_tx_submit(struct xen_netbk *netbk) |
| 1445 | { |
| 1446 | struct gnttab_copy *gop = netbk->tx_copy_ops; |
| 1447 | struct sk_buff *skb; |
| 1448 | |
| 1449 | while ((skb = __skb_dequeue(&netbk->tx_queue)) != NULL) { |
| 1450 | struct xen_netif_tx_request *txp; |
| 1451 | struct xenvif *vif; |
| 1452 | u16 pending_idx; |
| 1453 | unsigned data_len; |
| 1454 | |
| 1455 | pending_idx = *((u16 *)skb->data); |
| 1456 | vif = netbk->pending_tx_info[pending_idx].vif; |
| 1457 | txp = &netbk->pending_tx_info[pending_idx].req; |
| 1458 | |
| 1459 | /* Check the remap error code. */ |
| 1460 | if (unlikely(xen_netbk_tx_check_gop(netbk, skb, &gop))) { |
| 1461 | netdev_dbg(vif->dev, "netback grant failed.\n"); |
| 1462 | skb_shinfo(skb)->nr_frags = 0; |
| 1463 | kfree_skb(skb); |
| 1464 | continue; |
| 1465 | } |
| 1466 | |
| 1467 | data_len = skb->len; |
| 1468 | memcpy(skb->data, |
| 1469 | (void *)(idx_to_kaddr(netbk, pending_idx)|txp->offset), |
| 1470 | data_len); |
| 1471 | if (data_len < txp->size) { |
| 1472 | /* Append the packet payload as a fragment. */ |
| 1473 | txp->offset += data_len; |
| 1474 | txp->size -= data_len; |
| 1475 | } else { |
| 1476 | /* Schedule a response immediately. */ |
Matthew Daley | 7d5145d | 2013-02-06 23:41:36 +0000 | [diff] [blame] | 1477 | xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_OKAY); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1478 | } |
| 1479 | |
| 1480 | if (txp->flags & XEN_NETTXF_csum_blank) |
| 1481 | skb->ip_summed = CHECKSUM_PARTIAL; |
| 1482 | else if (txp->flags & XEN_NETTXF_data_validated) |
| 1483 | skb->ip_summed = CHECKSUM_UNNECESSARY; |
| 1484 | |
| 1485 | xen_netbk_fill_frags(netbk, skb); |
| 1486 | |
| 1487 | /* |
| 1488 | * If the initial fragment was < PKT_PROT_LEN then |
| 1489 | * pull through some bytes from the other fragments to |
| 1490 | * increase the linear region to PKT_PROT_LEN bytes. |
| 1491 | */ |
| 1492 | if (skb_headlen(skb) < PKT_PROT_LEN && skb_is_nonlinear(skb)) { |
| 1493 | int target = min_t(int, skb->len, PKT_PROT_LEN); |
| 1494 | __pskb_pull_tail(skb, target - skb_headlen(skb)); |
| 1495 | } |
| 1496 | |
| 1497 | skb->dev = vif->dev; |
| 1498 | skb->protocol = eth_type_trans(skb, skb->dev); |
| 1499 | |
| 1500 | if (checksum_setup(vif, skb)) { |
| 1501 | netdev_dbg(vif->dev, |
| 1502 | "Can't setup checksum in net_tx_action\n"); |
| 1503 | kfree_skb(skb); |
| 1504 | continue; |
| 1505 | } |
| 1506 | |
| 1507 | vif->dev->stats.rx_bytes += skb->len; |
| 1508 | vif->dev->stats.rx_packets++; |
| 1509 | |
| 1510 | xenvif_receive_skb(vif, skb); |
| 1511 | } |
| 1512 | } |
| 1513 | |
| 1514 | /* Called after netfront has transmitted */ |
| 1515 | static void xen_netbk_tx_action(struct xen_netbk *netbk) |
| 1516 | { |
| 1517 | unsigned nr_gops; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1518 | |
| 1519 | nr_gops = xen_netbk_tx_build_gops(netbk); |
| 1520 | |
| 1521 | if (nr_gops == 0) |
| 1522 | return; |
Andres Lagar-Cavilla | c571898 | 2012-09-14 14:26:59 +0000 | [diff] [blame] | 1523 | |
| 1524 | gnttab_batch_copy(netbk->tx_copy_ops, nr_gops); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1525 | |
| 1526 | xen_netbk_tx_submit(netbk); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1527 | } |
| 1528 | |
Matthew Daley | 7d5145d | 2013-02-06 23:41:36 +0000 | [diff] [blame] | 1529 | static void xen_netbk_idx_release(struct xen_netbk *netbk, u16 pending_idx, |
| 1530 | u8 status) |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1531 | { |
| 1532 | struct xenvif *vif; |
| 1533 | struct pending_tx_info *pending_tx_info; |
| 1534 | pending_ring_idx_t index; |
| 1535 | |
| 1536 | /* Already complete? */ |
| 1537 | if (netbk->mmap_pages[pending_idx] == NULL) |
| 1538 | return; |
| 1539 | |
| 1540 | pending_tx_info = &netbk->pending_tx_info[pending_idx]; |
| 1541 | |
| 1542 | vif = pending_tx_info->vif; |
| 1543 | |
Matthew Daley | 7d5145d | 2013-02-06 23:41:36 +0000 | [diff] [blame] | 1544 | make_tx_response(vif, &pending_tx_info->req, status); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1545 | |
| 1546 | index = pending_index(netbk->pending_prod++); |
| 1547 | netbk->pending_ring[index] = pending_idx; |
| 1548 | |
| 1549 | xenvif_put(vif); |
| 1550 | |
| 1551 | netbk->mmap_pages[pending_idx]->mapping = 0; |
| 1552 | put_page(netbk->mmap_pages[pending_idx]); |
| 1553 | netbk->mmap_pages[pending_idx] = NULL; |
| 1554 | } |
| 1555 | |
| 1556 | static void make_tx_response(struct xenvif *vif, |
| 1557 | struct xen_netif_tx_request *txp, |
| 1558 | s8 st) |
| 1559 | { |
| 1560 | RING_IDX i = vif->tx.rsp_prod_pvt; |
| 1561 | struct xen_netif_tx_response *resp; |
| 1562 | int notify; |
| 1563 | |
| 1564 | resp = RING_GET_RESPONSE(&vif->tx, i); |
| 1565 | resp->id = txp->id; |
| 1566 | resp->status = st; |
| 1567 | |
| 1568 | if (txp->flags & XEN_NETTXF_extra_info) |
| 1569 | RING_GET_RESPONSE(&vif->tx, ++i)->status = XEN_NETIF_RSP_NULL; |
| 1570 | |
| 1571 | vif->tx.rsp_prod_pvt = ++i; |
| 1572 | RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&vif->tx, notify); |
| 1573 | if (notify) |
| 1574 | notify_remote_via_irq(vif->irq); |
| 1575 | } |
| 1576 | |
| 1577 | static struct xen_netif_rx_response *make_rx_response(struct xenvif *vif, |
| 1578 | u16 id, |
| 1579 | s8 st, |
| 1580 | u16 offset, |
| 1581 | u16 size, |
| 1582 | u16 flags) |
| 1583 | { |
| 1584 | RING_IDX i = vif->rx.rsp_prod_pvt; |
| 1585 | struct xen_netif_rx_response *resp; |
| 1586 | |
| 1587 | resp = RING_GET_RESPONSE(&vif->rx, i); |
| 1588 | resp->offset = offset; |
| 1589 | resp->flags = flags; |
| 1590 | resp->id = id; |
| 1591 | resp->status = (s16)size; |
| 1592 | if (st < 0) |
| 1593 | resp->status = (s16)st; |
| 1594 | |
| 1595 | vif->rx.rsp_prod_pvt = ++i; |
| 1596 | |
| 1597 | return resp; |
| 1598 | } |
| 1599 | |
| 1600 | static inline int rx_work_todo(struct xen_netbk *netbk) |
| 1601 | { |
| 1602 | return !skb_queue_empty(&netbk->rx_queue); |
| 1603 | } |
| 1604 | |
| 1605 | static inline int tx_work_todo(struct xen_netbk *netbk) |
| 1606 | { |
| 1607 | |
| 1608 | if (((nr_pending_reqs(netbk) + MAX_SKB_FRAGS) < MAX_PENDING_REQS) && |
| 1609 | !list_empty(&netbk->net_schedule_list)) |
| 1610 | return 1; |
| 1611 | |
| 1612 | return 0; |
| 1613 | } |
| 1614 | |
| 1615 | static int xen_netbk_kthread(void *data) |
| 1616 | { |
| 1617 | struct xen_netbk *netbk = data; |
| 1618 | while (!kthread_should_stop()) { |
| 1619 | wait_event_interruptible(netbk->wq, |
| 1620 | rx_work_todo(netbk) || |
| 1621 | tx_work_todo(netbk) || |
| 1622 | kthread_should_stop()); |
| 1623 | cond_resched(); |
| 1624 | |
| 1625 | if (kthread_should_stop()) |
| 1626 | break; |
| 1627 | |
| 1628 | if (rx_work_todo(netbk)) |
| 1629 | xen_netbk_rx_action(netbk); |
| 1630 | |
| 1631 | if (tx_work_todo(netbk)) |
| 1632 | xen_netbk_tx_action(netbk); |
| 1633 | } |
| 1634 | |
| 1635 | return 0; |
| 1636 | } |
| 1637 | |
| 1638 | void xen_netbk_unmap_frontend_rings(struct xenvif *vif) |
| 1639 | { |
David Vrabel | c9d6369 | 2011-09-29 16:53:31 +0100 | [diff] [blame] | 1640 | if (vif->tx.sring) |
| 1641 | xenbus_unmap_ring_vfree(xenvif_to_xenbus_device(vif), |
| 1642 | vif->tx.sring); |
| 1643 | if (vif->rx.sring) |
| 1644 | xenbus_unmap_ring_vfree(xenvif_to_xenbus_device(vif), |
| 1645 | vif->rx.sring); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1646 | } |
| 1647 | |
| 1648 | int xen_netbk_map_frontend_rings(struct xenvif *vif, |
| 1649 | grant_ref_t tx_ring_ref, |
| 1650 | grant_ref_t rx_ring_ref) |
| 1651 | { |
David Vrabel | c9d6369 | 2011-09-29 16:53:31 +0100 | [diff] [blame] | 1652 | void *addr; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1653 | struct xen_netif_tx_sring *txs; |
| 1654 | struct xen_netif_rx_sring *rxs; |
| 1655 | |
| 1656 | int err = -ENOMEM; |
| 1657 | |
David Vrabel | c9d6369 | 2011-09-29 16:53:31 +0100 | [diff] [blame] | 1658 | err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(vif), |
| 1659 | tx_ring_ref, &addr); |
| 1660 | if (err) |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1661 | goto err; |
| 1662 | |
David Vrabel | c9d6369 | 2011-09-29 16:53:31 +0100 | [diff] [blame] | 1663 | txs = (struct xen_netif_tx_sring *)addr; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1664 | BACK_RING_INIT(&vif->tx, txs, PAGE_SIZE); |
| 1665 | |
David Vrabel | c9d6369 | 2011-09-29 16:53:31 +0100 | [diff] [blame] | 1666 | err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(vif), |
| 1667 | rx_ring_ref, &addr); |
| 1668 | if (err) |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1669 | goto err; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1670 | |
David Vrabel | c9d6369 | 2011-09-29 16:53:31 +0100 | [diff] [blame] | 1671 | rxs = (struct xen_netif_rx_sring *)addr; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1672 | BACK_RING_INIT(&vif->rx, rxs, PAGE_SIZE); |
| 1673 | |
David Vrabel | c9d6369 | 2011-09-29 16:53:31 +0100 | [diff] [blame] | 1674 | vif->rx_req_cons_peek = 0; |
| 1675 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1676 | return 0; |
| 1677 | |
| 1678 | err: |
| 1679 | xen_netbk_unmap_frontend_rings(vif); |
| 1680 | return err; |
| 1681 | } |
| 1682 | |
| 1683 | static int __init netback_init(void) |
| 1684 | { |
| 1685 | int i; |
| 1686 | int rc = 0; |
| 1687 | int group; |
| 1688 | |
Daniel De Graaf | 2a14b244 | 2011-12-14 15:12:13 -0500 | [diff] [blame] | 1689 | if (!xen_domain()) |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1690 | return -ENODEV; |
| 1691 | |
| 1692 | xen_netbk_group_nr = num_online_cpus(); |
| 1693 | xen_netbk = vzalloc(sizeof(struct xen_netbk) * xen_netbk_group_nr); |
Joe Perches | e404dec | 2012-01-29 12:56:23 +0000 | [diff] [blame] | 1694 | if (!xen_netbk) |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1695 | return -ENOMEM; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1696 | |
| 1697 | for (group = 0; group < xen_netbk_group_nr; group++) { |
| 1698 | struct xen_netbk *netbk = &xen_netbk[group]; |
| 1699 | skb_queue_head_init(&netbk->rx_queue); |
| 1700 | skb_queue_head_init(&netbk->tx_queue); |
| 1701 | |
| 1702 | init_timer(&netbk->net_timer); |
| 1703 | netbk->net_timer.data = (unsigned long)netbk; |
| 1704 | netbk->net_timer.function = xen_netbk_alarm; |
| 1705 | |
| 1706 | netbk->pending_cons = 0; |
| 1707 | netbk->pending_prod = MAX_PENDING_REQS; |
| 1708 | for (i = 0; i < MAX_PENDING_REQS; i++) |
| 1709 | netbk->pending_ring[i] = i; |
| 1710 | |
| 1711 | init_waitqueue_head(&netbk->wq); |
| 1712 | netbk->task = kthread_create(xen_netbk_kthread, |
| 1713 | (void *)netbk, |
| 1714 | "netback/%u", group); |
| 1715 | |
| 1716 | if (IS_ERR(netbk->task)) { |
Wei Liu | 6b84bd1 | 2011-12-05 06:57:44 +0000 | [diff] [blame] | 1717 | printk(KERN_ALERT "kthread_create() fails at netback\n"); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1718 | del_timer(&netbk->net_timer); |
| 1719 | rc = PTR_ERR(netbk->task); |
| 1720 | goto failed_init; |
| 1721 | } |
| 1722 | |
| 1723 | kthread_bind(netbk->task, group); |
| 1724 | |
| 1725 | INIT_LIST_HEAD(&netbk->net_schedule_list); |
| 1726 | |
| 1727 | spin_lock_init(&netbk->net_schedule_list_lock); |
| 1728 | |
| 1729 | atomic_set(&netbk->netfront_count, 0); |
| 1730 | |
| 1731 | wake_up_process(netbk->task); |
| 1732 | } |
| 1733 | |
| 1734 | rc = xenvif_xenbus_init(); |
| 1735 | if (rc) |
| 1736 | goto failed_init; |
| 1737 | |
| 1738 | return 0; |
| 1739 | |
| 1740 | failed_init: |
| 1741 | while (--group >= 0) { |
| 1742 | struct xen_netbk *netbk = &xen_netbk[group]; |
| 1743 | for (i = 0; i < MAX_PENDING_REQS; i++) { |
| 1744 | if (netbk->mmap_pages[i]) |
| 1745 | __free_page(netbk->mmap_pages[i]); |
| 1746 | } |
| 1747 | del_timer(&netbk->net_timer); |
| 1748 | kthread_stop(netbk->task); |
| 1749 | } |
| 1750 | vfree(xen_netbk); |
| 1751 | return rc; |
| 1752 | |
| 1753 | } |
| 1754 | |
| 1755 | module_init(netback_init); |
| 1756 | |
| 1757 | MODULE_LICENSE("Dual BSD/GPL"); |
Bastian Blank | f984cec | 2011-06-30 11:19:09 -0700 | [diff] [blame] | 1758 | MODULE_ALIAS("xen-backend:vif"); |