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f942dc25 IC |
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 | ||
43 | #include <xen/events.h> | |
44 | #include <xen/interface/memory.h> | |
45 | ||
46 | #include <asm/xen/hypercall.h> | |
47 | #include <asm/xen/page.h> | |
48 | ||
49 | struct pending_tx_info { | |
50 | struct xen_netif_tx_request req; | |
51 | struct xenvif *vif; | |
52 | }; | |
53 | typedef unsigned int pending_ring_idx_t; | |
54 | ||
55 | struct netbk_rx_meta { | |
56 | int id; | |
57 | int size; | |
58 | int gso_size; | |
59 | }; | |
60 | ||
61 | #define MAX_PENDING_REQS 256 | |
62 | ||
63 | #define MAX_BUFFER_OFFSET PAGE_SIZE | |
64 | ||
65 | /* extra field used in struct page */ | |
66 | union page_ext { | |
67 | struct { | |
68 | #if BITS_PER_LONG < 64 | |
69 | #define IDX_WIDTH 8 | |
70 | #define GROUP_WIDTH (BITS_PER_LONG - IDX_WIDTH) | |
71 | unsigned int group:GROUP_WIDTH; | |
72 | unsigned int idx:IDX_WIDTH; | |
73 | #else | |
74 | unsigned int group, idx; | |
75 | #endif | |
76 | } e; | |
77 | void *mapping; | |
78 | }; | |
79 | ||
80 | struct xen_netbk { | |
81 | wait_queue_head_t wq; | |
82 | struct task_struct *task; | |
83 | ||
84 | struct sk_buff_head rx_queue; | |
85 | struct sk_buff_head tx_queue; | |
86 | ||
87 | struct timer_list net_timer; | |
88 | ||
89 | struct page *mmap_pages[MAX_PENDING_REQS]; | |
90 | ||
91 | pending_ring_idx_t pending_prod; | |
92 | pending_ring_idx_t pending_cons; | |
93 | struct list_head net_schedule_list; | |
94 | ||
95 | /* Protect the net_schedule_list in netif. */ | |
96 | spinlock_t net_schedule_list_lock; | |
97 | ||
98 | atomic_t netfront_count; | |
99 | ||
100 | struct pending_tx_info pending_tx_info[MAX_PENDING_REQS]; | |
101 | struct gnttab_copy tx_copy_ops[MAX_PENDING_REQS]; | |
102 | ||
103 | u16 pending_ring[MAX_PENDING_REQS]; | |
104 | ||
105 | /* | |
106 | * Given MAX_BUFFER_OFFSET of 4096 the worst case is that each | |
107 | * head/fragment page uses 2 copy operations because it | |
108 | * straddles two buffers in the frontend. | |
109 | */ | |
110 | struct gnttab_copy grant_copy_op[2*XEN_NETIF_RX_RING_SIZE]; | |
111 | struct netbk_rx_meta meta[2*XEN_NETIF_RX_RING_SIZE]; | |
112 | }; | |
113 | ||
114 | static struct xen_netbk *xen_netbk; | |
115 | static int xen_netbk_group_nr; | |
116 | ||
117 | void xen_netbk_add_xenvif(struct xenvif *vif) | |
118 | { | |
119 | int i; | |
120 | int min_netfront_count; | |
121 | int min_group = 0; | |
122 | struct xen_netbk *netbk; | |
123 | ||
124 | min_netfront_count = atomic_read(&xen_netbk[0].netfront_count); | |
125 | for (i = 0; i < xen_netbk_group_nr; i++) { | |
126 | int netfront_count = atomic_read(&xen_netbk[i].netfront_count); | |
127 | if (netfront_count < min_netfront_count) { | |
128 | min_group = i; | |
129 | min_netfront_count = netfront_count; | |
130 | } | |
131 | } | |
132 | ||
133 | netbk = &xen_netbk[min_group]; | |
134 | ||
135 | vif->netbk = netbk; | |
136 | atomic_inc(&netbk->netfront_count); | |
137 | } | |
138 | ||
139 | void xen_netbk_remove_xenvif(struct xenvif *vif) | |
140 | { | |
141 | struct xen_netbk *netbk = vif->netbk; | |
142 | vif->netbk = NULL; | |
143 | atomic_dec(&netbk->netfront_count); | |
144 | } | |
145 | ||
146 | static void xen_netbk_idx_release(struct xen_netbk *netbk, u16 pending_idx); | |
147 | static void make_tx_response(struct xenvif *vif, | |
148 | struct xen_netif_tx_request *txp, | |
149 | s8 st); | |
150 | static struct xen_netif_rx_response *make_rx_response(struct xenvif *vif, | |
151 | u16 id, | |
152 | s8 st, | |
153 | u16 offset, | |
154 | u16 size, | |
155 | u16 flags); | |
156 | ||
157 | static inline unsigned long idx_to_pfn(struct xen_netbk *netbk, | |
158 | unsigned int idx) | |
159 | { | |
160 | return page_to_pfn(netbk->mmap_pages[idx]); | |
161 | } | |
162 | ||
163 | static inline unsigned long idx_to_kaddr(struct xen_netbk *netbk, | |
164 | unsigned int idx) | |
165 | { | |
166 | return (unsigned long)pfn_to_kaddr(idx_to_pfn(netbk, idx)); | |
167 | } | |
168 | ||
169 | /* extra field used in struct page */ | |
170 | static inline void set_page_ext(struct page *pg, struct xen_netbk *netbk, | |
171 | unsigned int idx) | |
172 | { | |
173 | unsigned int group = netbk - xen_netbk; | |
174 | union page_ext ext = { .e = { .group = group + 1, .idx = idx } }; | |
175 | ||
176 | BUILD_BUG_ON(sizeof(ext) > sizeof(ext.mapping)); | |
177 | pg->mapping = ext.mapping; | |
178 | } | |
179 | ||
180 | static int get_page_ext(struct page *pg, | |
181 | unsigned int *pgroup, unsigned int *pidx) | |
182 | { | |
183 | union page_ext ext = { .mapping = pg->mapping }; | |
184 | struct xen_netbk *netbk; | |
185 | unsigned int group, idx; | |
186 | ||
187 | group = ext.e.group - 1; | |
188 | ||
189 | if (group < 0 || group >= xen_netbk_group_nr) | |
190 | return 0; | |
191 | ||
192 | netbk = &xen_netbk[group]; | |
193 | ||
194 | idx = ext.e.idx; | |
195 | ||
196 | if ((idx < 0) || (idx >= MAX_PENDING_REQS)) | |
197 | return 0; | |
198 | ||
199 | if (netbk->mmap_pages[idx] != pg) | |
200 | return 0; | |
201 | ||
202 | *pgroup = group; | |
203 | *pidx = idx; | |
204 | ||
205 | return 1; | |
206 | } | |
207 | ||
208 | /* | |
209 | * This is the amount of packet we copy rather than map, so that the | |
210 | * guest can't fiddle with the contents of the headers while we do | |
211 | * packet processing on them (netfilter, routing, etc). | |
212 | */ | |
213 | #define PKT_PROT_LEN (ETH_HLEN + \ | |
214 | VLAN_HLEN + \ | |
215 | sizeof(struct iphdr) + MAX_IPOPTLEN + \ | |
216 | sizeof(struct tcphdr) + MAX_TCP_OPTION_SPACE) | |
217 | ||
218 | static inline pending_ring_idx_t pending_index(unsigned i) | |
219 | { | |
220 | return i & (MAX_PENDING_REQS-1); | |
221 | } | |
222 | ||
223 | static inline pending_ring_idx_t nr_pending_reqs(struct xen_netbk *netbk) | |
224 | { | |
225 | return MAX_PENDING_REQS - | |
226 | netbk->pending_prod + netbk->pending_cons; | |
227 | } | |
228 | ||
229 | static void xen_netbk_kick_thread(struct xen_netbk *netbk) | |
230 | { | |
231 | wake_up(&netbk->wq); | |
232 | } | |
233 | ||
234 | static int max_required_rx_slots(struct xenvif *vif) | |
235 | { | |
236 | int max = DIV_ROUND_UP(vif->dev->mtu, PAGE_SIZE); | |
237 | ||
238 | if (vif->can_sg || vif->gso || vif->gso_prefix) | |
239 | max += MAX_SKB_FRAGS + 1; /* extra_info + frags */ | |
240 | ||
241 | return max; | |
242 | } | |
243 | ||
244 | int xen_netbk_rx_ring_full(struct xenvif *vif) | |
245 | { | |
246 | RING_IDX peek = vif->rx_req_cons_peek; | |
247 | RING_IDX needed = max_required_rx_slots(vif); | |
248 | ||
249 | return ((vif->rx.sring->req_prod - peek) < needed) || | |
250 | ((vif->rx.rsp_prod_pvt + XEN_NETIF_RX_RING_SIZE - peek) < needed); | |
251 | } | |
252 | ||
253 | int xen_netbk_must_stop_queue(struct xenvif *vif) | |
254 | { | |
255 | if (!xen_netbk_rx_ring_full(vif)) | |
256 | return 0; | |
257 | ||
258 | vif->rx.sring->req_event = vif->rx_req_cons_peek + | |
259 | max_required_rx_slots(vif); | |
260 | mb(); /* request notification /then/ check the queue */ | |
261 | ||
262 | return xen_netbk_rx_ring_full(vif); | |
263 | } | |
264 | ||
265 | /* | |
266 | * Returns true if we should start a new receive buffer instead of | |
267 | * adding 'size' bytes to a buffer which currently contains 'offset' | |
268 | * bytes. | |
269 | */ | |
270 | static bool start_new_rx_buffer(int offset, unsigned long size, int head) | |
271 | { | |
272 | /* simple case: we have completely filled the current buffer. */ | |
273 | if (offset == MAX_BUFFER_OFFSET) | |
274 | return true; | |
275 | ||
276 | /* | |
277 | * complex case: start a fresh buffer if the current frag | |
278 | * would overflow the current buffer but only if: | |
279 | * (i) this frag would fit completely in the next buffer | |
280 | * and (ii) there is already some data in the current buffer | |
281 | * and (iii) this is not the head buffer. | |
282 | * | |
283 | * Where: | |
284 | * - (i) stops us splitting a frag into two copies | |
285 | * unless the frag is too large for a single buffer. | |
286 | * - (ii) stops us from leaving a buffer pointlessly empty. | |
287 | * - (iii) stops us leaving the first buffer | |
288 | * empty. Strictly speaking this is already covered | |
289 | * by (ii) but is explicitly checked because | |
290 | * netfront relies on the first buffer being | |
291 | * non-empty and can crash otherwise. | |
292 | * | |
293 | * This means we will effectively linearise small | |
294 | * frags but do not needlessly split large buffers | |
295 | * into multiple copies tend to give large frags their | |
296 | * own buffers as before. | |
297 | */ | |
298 | if ((offset + size > MAX_BUFFER_OFFSET) && | |
299 | (size <= MAX_BUFFER_OFFSET) && offset && !head) | |
300 | return true; | |
301 | ||
302 | return false; | |
303 | } | |
304 | ||
305 | /* | |
306 | * Figure out how many ring slots we're going to need to send @skb to | |
307 | * the guest. This function is essentially a dry run of | |
308 | * netbk_gop_frag_copy. | |
309 | */ | |
310 | unsigned int xen_netbk_count_skb_slots(struct xenvif *vif, struct sk_buff *skb) | |
311 | { | |
312 | unsigned int count; | |
313 | int i, copy_off; | |
314 | ||
315 | count = DIV_ROUND_UP( | |
316 | offset_in_page(skb->data)+skb_headlen(skb), PAGE_SIZE); | |
317 | ||
318 | copy_off = skb_headlen(skb) % PAGE_SIZE; | |
319 | ||
320 | if (skb_shinfo(skb)->gso_size) | |
321 | count++; | |
322 | ||
323 | for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { | |
324 | unsigned long size = skb_shinfo(skb)->frags[i].size; | |
325 | unsigned long bytes; | |
326 | while (size > 0) { | |
327 | BUG_ON(copy_off > MAX_BUFFER_OFFSET); | |
328 | ||
329 | if (start_new_rx_buffer(copy_off, size, 0)) { | |
330 | count++; | |
331 | copy_off = 0; | |
332 | } | |
333 | ||
334 | bytes = size; | |
335 | if (copy_off + bytes > MAX_BUFFER_OFFSET) | |
336 | bytes = MAX_BUFFER_OFFSET - copy_off; | |
337 | ||
338 | copy_off += bytes; | |
339 | size -= bytes; | |
340 | } | |
341 | } | |
342 | return count; | |
343 | } | |
344 | ||
345 | struct netrx_pending_operations { | |
346 | unsigned copy_prod, copy_cons; | |
347 | unsigned meta_prod, meta_cons; | |
348 | struct gnttab_copy *copy; | |
349 | struct netbk_rx_meta *meta; | |
350 | int copy_off; | |
351 | grant_ref_t copy_gref; | |
352 | }; | |
353 | ||
354 | static struct netbk_rx_meta *get_next_rx_buffer(struct xenvif *vif, | |
355 | struct netrx_pending_operations *npo) | |
356 | { | |
357 | struct netbk_rx_meta *meta; | |
358 | struct xen_netif_rx_request *req; | |
359 | ||
360 | req = RING_GET_REQUEST(&vif->rx, vif->rx.req_cons++); | |
361 | ||
362 | meta = npo->meta + npo->meta_prod++; | |
363 | meta->gso_size = 0; | |
364 | meta->size = 0; | |
365 | meta->id = req->id; | |
366 | ||
367 | npo->copy_off = 0; | |
368 | npo->copy_gref = req->gref; | |
369 | ||
370 | return meta; | |
371 | } | |
372 | ||
373 | /* | |
374 | * Set up the grant operations for this fragment. If it's a flipping | |
375 | * interface, we also set up the unmap request from here. | |
376 | */ | |
377 | static void netbk_gop_frag_copy(struct xenvif *vif, struct sk_buff *skb, | |
378 | struct netrx_pending_operations *npo, | |
379 | struct page *page, unsigned long size, | |
380 | unsigned long offset, int *head) | |
381 | { | |
382 | struct gnttab_copy *copy_gop; | |
383 | struct netbk_rx_meta *meta; | |
384 | /* | |
385 | * These variables a used iff get_page_ext returns true, | |
386 | * in which case they are guaranteed to be initialized. | |
387 | */ | |
388 | unsigned int uninitialized_var(group), uninitialized_var(idx); | |
389 | int foreign = get_page_ext(page, &group, &idx); | |
390 | unsigned long bytes; | |
391 | ||
392 | /* Data must not cross a page boundary. */ | |
393 | BUG_ON(size + offset > PAGE_SIZE); | |
394 | ||
395 | meta = npo->meta + npo->meta_prod - 1; | |
396 | ||
397 | while (size > 0) { | |
398 | BUG_ON(npo->copy_off > MAX_BUFFER_OFFSET); | |
399 | ||
400 | if (start_new_rx_buffer(npo->copy_off, size, *head)) { | |
401 | /* | |
402 | * Netfront requires there to be some data in the head | |
403 | * buffer. | |
404 | */ | |
405 | BUG_ON(*head); | |
406 | ||
407 | meta = get_next_rx_buffer(vif, npo); | |
408 | } | |
409 | ||
410 | bytes = size; | |
411 | if (npo->copy_off + bytes > MAX_BUFFER_OFFSET) | |
412 | bytes = MAX_BUFFER_OFFSET - npo->copy_off; | |
413 | ||
414 | copy_gop = npo->copy + npo->copy_prod++; | |
415 | copy_gop->flags = GNTCOPY_dest_gref; | |
416 | if (foreign) { | |
417 | struct xen_netbk *netbk = &xen_netbk[group]; | |
418 | struct pending_tx_info *src_pend; | |
419 | ||
420 | src_pend = &netbk->pending_tx_info[idx]; | |
421 | ||
422 | copy_gop->source.domid = src_pend->vif->domid; | |
423 | copy_gop->source.u.ref = src_pend->req.gref; | |
424 | copy_gop->flags |= GNTCOPY_source_gref; | |
425 | } else { | |
426 | void *vaddr = page_address(page); | |
427 | copy_gop->source.domid = DOMID_SELF; | |
428 | copy_gop->source.u.gmfn = virt_to_mfn(vaddr); | |
429 | } | |
430 | copy_gop->source.offset = offset; | |
431 | copy_gop->dest.domid = vif->domid; | |
432 | ||
433 | copy_gop->dest.offset = npo->copy_off; | |
434 | copy_gop->dest.u.ref = npo->copy_gref; | |
435 | copy_gop->len = bytes; | |
436 | ||
437 | npo->copy_off += bytes; | |
438 | meta->size += bytes; | |
439 | ||
440 | offset += bytes; | |
441 | size -= bytes; | |
442 | ||
443 | /* Leave a gap for the GSO descriptor. */ | |
444 | if (*head && skb_shinfo(skb)->gso_size && !vif->gso_prefix) | |
445 | vif->rx.req_cons++; | |
446 | ||
447 | *head = 0; /* There must be something in this buffer now. */ | |
448 | ||
449 | } | |
450 | } | |
451 | ||
452 | /* | |
453 | * Prepare an SKB to be transmitted to the frontend. | |
454 | * | |
455 | * This function is responsible for allocating grant operations, meta | |
456 | * structures, etc. | |
457 | * | |
458 | * It returns the number of meta structures consumed. The number of | |
459 | * ring slots used is always equal to the number of meta slots used | |
460 | * plus the number of GSO descriptors used. Currently, we use either | |
461 | * zero GSO descriptors (for non-GSO packets) or one descriptor (for | |
462 | * frontend-side LRO). | |
463 | */ | |
464 | static int netbk_gop_skb(struct sk_buff *skb, | |
465 | struct netrx_pending_operations *npo) | |
466 | { | |
467 | struct xenvif *vif = netdev_priv(skb->dev); | |
468 | int nr_frags = skb_shinfo(skb)->nr_frags; | |
469 | int i; | |
470 | struct xen_netif_rx_request *req; | |
471 | struct netbk_rx_meta *meta; | |
472 | unsigned char *data; | |
473 | int head = 1; | |
474 | int old_meta_prod; | |
475 | ||
476 | old_meta_prod = npo->meta_prod; | |
477 | ||
478 | /* Set up a GSO prefix descriptor, if necessary */ | |
479 | if (skb_shinfo(skb)->gso_size && vif->gso_prefix) { | |
480 | req = RING_GET_REQUEST(&vif->rx, vif->rx.req_cons++); | |
481 | meta = npo->meta + npo->meta_prod++; | |
482 | meta->gso_size = skb_shinfo(skb)->gso_size; | |
483 | meta->size = 0; | |
484 | meta->id = req->id; | |
485 | } | |
486 | ||
487 | req = RING_GET_REQUEST(&vif->rx, vif->rx.req_cons++); | |
488 | meta = npo->meta + npo->meta_prod++; | |
489 | ||
490 | if (!vif->gso_prefix) | |
491 | meta->gso_size = skb_shinfo(skb)->gso_size; | |
492 | else | |
493 | meta->gso_size = 0; | |
494 | ||
495 | meta->size = 0; | |
496 | meta->id = req->id; | |
497 | npo->copy_off = 0; | |
498 | npo->copy_gref = req->gref; | |
499 | ||
500 | data = skb->data; | |
501 | while (data < skb_tail_pointer(skb)) { | |
502 | unsigned int offset = offset_in_page(data); | |
503 | unsigned int len = PAGE_SIZE - offset; | |
504 | ||
505 | if (data + len > skb_tail_pointer(skb)) | |
506 | len = skb_tail_pointer(skb) - data; | |
507 | ||
508 | netbk_gop_frag_copy(vif, skb, npo, | |
509 | virt_to_page(data), len, offset, &head); | |
510 | data += len; | |
511 | } | |
512 | ||
513 | for (i = 0; i < nr_frags; i++) { | |
514 | netbk_gop_frag_copy(vif, skb, npo, | |
515 | skb_shinfo(skb)->frags[i].page, | |
516 | skb_shinfo(skb)->frags[i].size, | |
517 | skb_shinfo(skb)->frags[i].page_offset, | |
518 | &head); | |
519 | } | |
520 | ||
521 | return npo->meta_prod - old_meta_prod; | |
522 | } | |
523 | ||
524 | /* | |
525 | * This is a twin to netbk_gop_skb. Assume that netbk_gop_skb was | |
526 | * used to set up the operations on the top of | |
527 | * netrx_pending_operations, which have since been done. Check that | |
528 | * they didn't give any errors and advance over them. | |
529 | */ | |
530 | static int netbk_check_gop(struct xenvif *vif, int nr_meta_slots, | |
531 | struct netrx_pending_operations *npo) | |
532 | { | |
533 | struct gnttab_copy *copy_op; | |
534 | int status = XEN_NETIF_RSP_OKAY; | |
535 | int i; | |
536 | ||
537 | for (i = 0; i < nr_meta_slots; i++) { | |
538 | copy_op = npo->copy + npo->copy_cons++; | |
539 | if (copy_op->status != GNTST_okay) { | |
540 | netdev_dbg(vif->dev, | |
541 | "Bad status %d from copy to DOM%d.\n", | |
542 | copy_op->status, vif->domid); | |
543 | status = XEN_NETIF_RSP_ERROR; | |
544 | } | |
545 | } | |
546 | ||
547 | return status; | |
548 | } | |
549 | ||
550 | static void netbk_add_frag_responses(struct xenvif *vif, int status, | |
551 | struct netbk_rx_meta *meta, | |
552 | int nr_meta_slots) | |
553 | { | |
554 | int i; | |
555 | unsigned long offset; | |
556 | ||
557 | /* No fragments used */ | |
558 | if (nr_meta_slots <= 1) | |
559 | return; | |
560 | ||
561 | nr_meta_slots--; | |
562 | ||
563 | for (i = 0; i < nr_meta_slots; i++) { | |
564 | int flags; | |
565 | if (i == nr_meta_slots - 1) | |
566 | flags = 0; | |
567 | else | |
568 | flags = XEN_NETRXF_more_data; | |
569 | ||
570 | offset = 0; | |
571 | make_rx_response(vif, meta[i].id, status, offset, | |
572 | meta[i].size, flags); | |
573 | } | |
574 | } | |
575 | ||
576 | struct skb_cb_overlay { | |
577 | int meta_slots_used; | |
578 | }; | |
579 | ||
580 | static void xen_netbk_rx_action(struct xen_netbk *netbk) | |
581 | { | |
582 | struct xenvif *vif = NULL, *tmp; | |
583 | s8 status; | |
584 | u16 irq, flags; | |
585 | struct xen_netif_rx_response *resp; | |
586 | struct sk_buff_head rxq; | |
587 | struct sk_buff *skb; | |
588 | LIST_HEAD(notify); | |
589 | int ret; | |
590 | int nr_frags; | |
591 | int count; | |
592 | unsigned long offset; | |
593 | struct skb_cb_overlay *sco; | |
594 | ||
595 | struct netrx_pending_operations npo = { | |
596 | .copy = netbk->grant_copy_op, | |
597 | .meta = netbk->meta, | |
598 | }; | |
599 | ||
600 | skb_queue_head_init(&rxq); | |
601 | ||
602 | count = 0; | |
603 | ||
604 | while ((skb = skb_dequeue(&netbk->rx_queue)) != NULL) { | |
605 | vif = netdev_priv(skb->dev); | |
606 | nr_frags = skb_shinfo(skb)->nr_frags; | |
607 | ||
608 | sco = (struct skb_cb_overlay *)skb->cb; | |
609 | sco->meta_slots_used = netbk_gop_skb(skb, &npo); | |
610 | ||
611 | count += nr_frags + 1; | |
612 | ||
613 | __skb_queue_tail(&rxq, skb); | |
614 | ||
615 | /* Filled the batch queue? */ | |
616 | if (count + MAX_SKB_FRAGS >= XEN_NETIF_RX_RING_SIZE) | |
617 | break; | |
618 | } | |
619 | ||
620 | BUG_ON(npo.meta_prod > ARRAY_SIZE(netbk->meta)); | |
621 | ||
622 | if (!npo.copy_prod) | |
623 | return; | |
624 | ||
625 | BUG_ON(npo.copy_prod > ARRAY_SIZE(netbk->grant_copy_op)); | |
626 | ret = HYPERVISOR_grant_table_op(GNTTABOP_copy, &netbk->grant_copy_op, | |
627 | npo.copy_prod); | |
628 | BUG_ON(ret != 0); | |
629 | ||
630 | while ((skb = __skb_dequeue(&rxq)) != NULL) { | |
631 | sco = (struct skb_cb_overlay *)skb->cb; | |
632 | ||
633 | vif = netdev_priv(skb->dev); | |
634 | ||
635 | if (netbk->meta[npo.meta_cons].gso_size && vif->gso_prefix) { | |
636 | resp = RING_GET_RESPONSE(&vif->rx, | |
637 | vif->rx.rsp_prod_pvt++); | |
638 | ||
639 | resp->flags = XEN_NETRXF_gso_prefix | XEN_NETRXF_more_data; | |
640 | ||
641 | resp->offset = netbk->meta[npo.meta_cons].gso_size; | |
642 | resp->id = netbk->meta[npo.meta_cons].id; | |
643 | resp->status = sco->meta_slots_used; | |
644 | ||
645 | npo.meta_cons++; | |
646 | sco->meta_slots_used--; | |
647 | } | |
648 | ||
649 | ||
650 | vif->dev->stats.tx_bytes += skb->len; | |
651 | vif->dev->stats.tx_packets++; | |
652 | ||
653 | status = netbk_check_gop(vif, sco->meta_slots_used, &npo); | |
654 | ||
655 | if (sco->meta_slots_used == 1) | |
656 | flags = 0; | |
657 | else | |
658 | flags = XEN_NETRXF_more_data; | |
659 | ||
660 | if (skb->ip_summed == CHECKSUM_PARTIAL) /* local packet? */ | |
661 | flags |= XEN_NETRXF_csum_blank | XEN_NETRXF_data_validated; | |
662 | else if (skb->ip_summed == CHECKSUM_UNNECESSARY) | |
663 | /* remote but checksummed. */ | |
664 | flags |= XEN_NETRXF_data_validated; | |
665 | ||
666 | offset = 0; | |
667 | resp = make_rx_response(vif, netbk->meta[npo.meta_cons].id, | |
668 | status, offset, | |
669 | netbk->meta[npo.meta_cons].size, | |
670 | flags); | |
671 | ||
672 | if (netbk->meta[npo.meta_cons].gso_size && !vif->gso_prefix) { | |
673 | struct xen_netif_extra_info *gso = | |
674 | (struct xen_netif_extra_info *) | |
675 | RING_GET_RESPONSE(&vif->rx, | |
676 | vif->rx.rsp_prod_pvt++); | |
677 | ||
678 | resp->flags |= XEN_NETRXF_extra_info; | |
679 | ||
680 | gso->u.gso.size = netbk->meta[npo.meta_cons].gso_size; | |
681 | gso->u.gso.type = XEN_NETIF_GSO_TYPE_TCPV4; | |
682 | gso->u.gso.pad = 0; | |
683 | gso->u.gso.features = 0; | |
684 | ||
685 | gso->type = XEN_NETIF_EXTRA_TYPE_GSO; | |
686 | gso->flags = 0; | |
687 | } | |
688 | ||
689 | netbk_add_frag_responses(vif, status, | |
690 | netbk->meta + npo.meta_cons + 1, | |
691 | sco->meta_slots_used); | |
692 | ||
693 | RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&vif->rx, ret); | |
694 | irq = vif->irq; | |
695 | if (ret && list_empty(&vif->notify_list)) | |
696 | list_add_tail(&vif->notify_list, ¬ify); | |
697 | ||
698 | xenvif_notify_tx_completion(vif); | |
699 | ||
700 | xenvif_put(vif); | |
701 | npo.meta_cons += sco->meta_slots_used; | |
702 | dev_kfree_skb(skb); | |
703 | } | |
704 | ||
705 | list_for_each_entry_safe(vif, tmp, ¬ify, notify_list) { | |
706 | notify_remote_via_irq(vif->irq); | |
707 | list_del_init(&vif->notify_list); | |
708 | } | |
709 | ||
710 | /* More work to do? */ | |
711 | if (!skb_queue_empty(&netbk->rx_queue) && | |
712 | !timer_pending(&netbk->net_timer)) | |
713 | xen_netbk_kick_thread(netbk); | |
714 | } | |
715 | ||
716 | void xen_netbk_queue_tx_skb(struct xenvif *vif, struct sk_buff *skb) | |
717 | { | |
718 | struct xen_netbk *netbk = vif->netbk; | |
719 | ||
720 | skb_queue_tail(&netbk->rx_queue, skb); | |
721 | ||
722 | xen_netbk_kick_thread(netbk); | |
723 | } | |
724 | ||
725 | static void xen_netbk_alarm(unsigned long data) | |
726 | { | |
727 | struct xen_netbk *netbk = (struct xen_netbk *)data; | |
728 | xen_netbk_kick_thread(netbk); | |
729 | } | |
730 | ||
731 | static int __on_net_schedule_list(struct xenvif *vif) | |
732 | { | |
733 | return !list_empty(&vif->schedule_list); | |
734 | } | |
735 | ||
736 | /* Must be called with net_schedule_list_lock held */ | |
737 | static void remove_from_net_schedule_list(struct xenvif *vif) | |
738 | { | |
739 | if (likely(__on_net_schedule_list(vif))) { | |
740 | list_del_init(&vif->schedule_list); | |
741 | xenvif_put(vif); | |
742 | } | |
743 | } | |
744 | ||
745 | static struct xenvif *poll_net_schedule_list(struct xen_netbk *netbk) | |
746 | { | |
747 | struct xenvif *vif = NULL; | |
748 | ||
749 | spin_lock_irq(&netbk->net_schedule_list_lock); | |
750 | if (list_empty(&netbk->net_schedule_list)) | |
751 | goto out; | |
752 | ||
753 | vif = list_first_entry(&netbk->net_schedule_list, | |
754 | struct xenvif, schedule_list); | |
755 | if (!vif) | |
756 | goto out; | |
757 | ||
758 | xenvif_get(vif); | |
759 | ||
760 | remove_from_net_schedule_list(vif); | |
761 | out: | |
762 | spin_unlock_irq(&netbk->net_schedule_list_lock); | |
763 | return vif; | |
764 | } | |
765 | ||
766 | void xen_netbk_schedule_xenvif(struct xenvif *vif) | |
767 | { | |
768 | unsigned long flags; | |
769 | struct xen_netbk *netbk = vif->netbk; | |
770 | ||
771 | if (__on_net_schedule_list(vif)) | |
772 | goto kick; | |
773 | ||
774 | spin_lock_irqsave(&netbk->net_schedule_list_lock, flags); | |
775 | if (!__on_net_schedule_list(vif) && | |
776 | likely(xenvif_schedulable(vif))) { | |
777 | list_add_tail(&vif->schedule_list, &netbk->net_schedule_list); | |
778 | xenvif_get(vif); | |
779 | } | |
780 | spin_unlock_irqrestore(&netbk->net_schedule_list_lock, flags); | |
781 | ||
782 | kick: | |
783 | smp_mb(); | |
784 | if ((nr_pending_reqs(netbk) < (MAX_PENDING_REQS/2)) && | |
785 | !list_empty(&netbk->net_schedule_list)) | |
786 | xen_netbk_kick_thread(netbk); | |
787 | } | |
788 | ||
789 | void xen_netbk_deschedule_xenvif(struct xenvif *vif) | |
790 | { | |
791 | struct xen_netbk *netbk = vif->netbk; | |
792 | spin_lock_irq(&netbk->net_schedule_list_lock); | |
793 | remove_from_net_schedule_list(vif); | |
794 | spin_unlock_irq(&netbk->net_schedule_list_lock); | |
795 | } | |
796 | ||
797 | void xen_netbk_check_rx_xenvif(struct xenvif *vif) | |
798 | { | |
799 | int more_to_do; | |
800 | ||
801 | RING_FINAL_CHECK_FOR_REQUESTS(&vif->tx, more_to_do); | |
802 | ||
803 | if (more_to_do) | |
804 | xen_netbk_schedule_xenvif(vif); | |
805 | } | |
806 | ||
807 | static void tx_add_credit(struct xenvif *vif) | |
808 | { | |
809 | unsigned long max_burst, max_credit; | |
810 | ||
811 | /* | |
812 | * Allow a burst big enough to transmit a jumbo packet of up to 128kB. | |
813 | * Otherwise the interface can seize up due to insufficient credit. | |
814 | */ | |
815 | max_burst = RING_GET_REQUEST(&vif->tx, vif->tx.req_cons)->size; | |
816 | max_burst = min(max_burst, 131072UL); | |
817 | max_burst = max(max_burst, vif->credit_bytes); | |
818 | ||
819 | /* Take care that adding a new chunk of credit doesn't wrap to zero. */ | |
820 | max_credit = vif->remaining_credit + vif->credit_bytes; | |
821 | if (max_credit < vif->remaining_credit) | |
822 | max_credit = ULONG_MAX; /* wrapped: clamp to ULONG_MAX */ | |
823 | ||
824 | vif->remaining_credit = min(max_credit, max_burst); | |
825 | } | |
826 | ||
827 | static void tx_credit_callback(unsigned long data) | |
828 | { | |
829 | struct xenvif *vif = (struct xenvif *)data; | |
830 | tx_add_credit(vif); | |
831 | xen_netbk_check_rx_xenvif(vif); | |
832 | } | |
833 | ||
834 | static void netbk_tx_err(struct xenvif *vif, | |
835 | struct xen_netif_tx_request *txp, RING_IDX end) | |
836 | { | |
837 | RING_IDX cons = vif->tx.req_cons; | |
838 | ||
839 | do { | |
840 | make_tx_response(vif, txp, XEN_NETIF_RSP_ERROR); | |
841 | if (cons >= end) | |
842 | break; | |
843 | txp = RING_GET_REQUEST(&vif->tx, cons++); | |
844 | } while (1); | |
845 | vif->tx.req_cons = cons; | |
846 | xen_netbk_check_rx_xenvif(vif); | |
847 | xenvif_put(vif); | |
848 | } | |
849 | ||
850 | static int netbk_count_requests(struct xenvif *vif, | |
851 | struct xen_netif_tx_request *first, | |
852 | struct xen_netif_tx_request *txp, | |
853 | int work_to_do) | |
854 | { | |
855 | RING_IDX cons = vif->tx.req_cons; | |
856 | int frags = 0; | |
857 | ||
858 | if (!(first->flags & XEN_NETTXF_more_data)) | |
859 | return 0; | |
860 | ||
861 | do { | |
862 | if (frags >= work_to_do) { | |
863 | netdev_dbg(vif->dev, "Need more frags\n"); | |
864 | return -frags; | |
865 | } | |
866 | ||
867 | if (unlikely(frags >= MAX_SKB_FRAGS)) { | |
868 | netdev_dbg(vif->dev, "Too many frags\n"); | |
869 | return -frags; | |
870 | } | |
871 | ||
872 | memcpy(txp, RING_GET_REQUEST(&vif->tx, cons + frags), | |
873 | sizeof(*txp)); | |
874 | if (txp->size > first->size) { | |
875 | netdev_dbg(vif->dev, "Frags galore\n"); | |
876 | return -frags; | |
877 | } | |
878 | ||
879 | first->size -= txp->size; | |
880 | frags++; | |
881 | ||
882 | if (unlikely((txp->offset + txp->size) > PAGE_SIZE)) { | |
883 | netdev_dbg(vif->dev, "txp->offset: %x, size: %u\n", | |
884 | txp->offset, txp->size); | |
885 | return -frags; | |
886 | } | |
887 | } while ((txp++)->flags & XEN_NETTXF_more_data); | |
888 | return frags; | |
889 | } | |
890 | ||
891 | static struct page *xen_netbk_alloc_page(struct xen_netbk *netbk, | |
892 | struct sk_buff *skb, | |
893 | unsigned long pending_idx) | |
894 | { | |
895 | struct page *page; | |
896 | page = alloc_page(GFP_KERNEL|__GFP_COLD); | |
897 | if (!page) | |
898 | return NULL; | |
899 | set_page_ext(page, netbk, pending_idx); | |
900 | netbk->mmap_pages[pending_idx] = page; | |
901 | return page; | |
902 | } | |
903 | ||
904 | static struct gnttab_copy *xen_netbk_get_requests(struct xen_netbk *netbk, | |
905 | struct xenvif *vif, | |
906 | struct sk_buff *skb, | |
907 | struct xen_netif_tx_request *txp, | |
908 | struct gnttab_copy *gop) | |
909 | { | |
910 | struct skb_shared_info *shinfo = skb_shinfo(skb); | |
911 | skb_frag_t *frags = shinfo->frags; | |
912 | unsigned long pending_idx = *((u16 *)skb->data); | |
913 | int i, start; | |
914 | ||
915 | /* Skip first skb fragment if it is on same page as header fragment. */ | |
916 | start = ((unsigned long)shinfo->frags[0].page == pending_idx); | |
917 | ||
918 | for (i = start; i < shinfo->nr_frags; i++, txp++) { | |
919 | struct page *page; | |
920 | pending_ring_idx_t index; | |
921 | struct pending_tx_info *pending_tx_info = | |
922 | netbk->pending_tx_info; | |
923 | ||
924 | index = pending_index(netbk->pending_cons++); | |
925 | pending_idx = netbk->pending_ring[index]; | |
926 | page = xen_netbk_alloc_page(netbk, skb, pending_idx); | |
927 | if (!page) | |
928 | return NULL; | |
929 | ||
930 | netbk->mmap_pages[pending_idx] = page; | |
931 | ||
932 | gop->source.u.ref = txp->gref; | |
933 | gop->source.domid = vif->domid; | |
934 | gop->source.offset = txp->offset; | |
935 | ||
936 | gop->dest.u.gmfn = virt_to_mfn(page_address(page)); | |
937 | gop->dest.domid = DOMID_SELF; | |
938 | gop->dest.offset = txp->offset; | |
939 | ||
940 | gop->len = txp->size; | |
941 | gop->flags = GNTCOPY_source_gref; | |
942 | ||
943 | gop++; | |
944 | ||
945 | memcpy(&pending_tx_info[pending_idx].req, txp, sizeof(*txp)); | |
946 | xenvif_get(vif); | |
947 | pending_tx_info[pending_idx].vif = vif; | |
948 | frags[i].page = (void *)pending_idx; | |
949 | } | |
950 | ||
951 | return gop; | |
952 | } | |
953 | ||
954 | static int xen_netbk_tx_check_gop(struct xen_netbk *netbk, | |
955 | struct sk_buff *skb, | |
956 | struct gnttab_copy **gopp) | |
957 | { | |
958 | struct gnttab_copy *gop = *gopp; | |
959 | int pending_idx = *((u16 *)skb->data); | |
960 | struct pending_tx_info *pending_tx_info = netbk->pending_tx_info; | |
961 | struct xenvif *vif = pending_tx_info[pending_idx].vif; | |
962 | struct xen_netif_tx_request *txp; | |
963 | struct skb_shared_info *shinfo = skb_shinfo(skb); | |
964 | int nr_frags = shinfo->nr_frags; | |
965 | int i, err, start; | |
966 | ||
967 | /* Check status of header. */ | |
968 | err = gop->status; | |
969 | if (unlikely(err)) { | |
970 | pending_ring_idx_t index; | |
971 | index = pending_index(netbk->pending_prod++); | |
972 | txp = &pending_tx_info[pending_idx].req; | |
973 | make_tx_response(vif, txp, XEN_NETIF_RSP_ERROR); | |
974 | netbk->pending_ring[index] = pending_idx; | |
975 | xenvif_put(vif); | |
976 | } | |
977 | ||
978 | /* Skip first skb fragment if it is on same page as header fragment. */ | |
979 | start = ((unsigned long)shinfo->frags[0].page == pending_idx); | |
980 | ||
981 | for (i = start; i < nr_frags; i++) { | |
982 | int j, newerr; | |
983 | pending_ring_idx_t index; | |
984 | ||
985 | pending_idx = (unsigned long)shinfo->frags[i].page; | |
986 | ||
987 | /* Check error status: if okay then remember grant handle. */ | |
988 | newerr = (++gop)->status; | |
989 | if (likely(!newerr)) { | |
990 | /* Had a previous error? Invalidate this fragment. */ | |
991 | if (unlikely(err)) | |
992 | xen_netbk_idx_release(netbk, pending_idx); | |
993 | continue; | |
994 | } | |
995 | ||
996 | /* Error on this fragment: respond to client with an error. */ | |
997 | txp = &netbk->pending_tx_info[pending_idx].req; | |
998 | make_tx_response(vif, txp, XEN_NETIF_RSP_ERROR); | |
999 | index = pending_index(netbk->pending_prod++); | |
1000 | netbk->pending_ring[index] = pending_idx; | |
1001 | xenvif_put(vif); | |
1002 | ||
1003 | /* Not the first error? Preceding frags already invalidated. */ | |
1004 | if (err) | |
1005 | continue; | |
1006 | ||
1007 | /* First error: invalidate header and preceding fragments. */ | |
1008 | pending_idx = *((u16 *)skb->data); | |
1009 | xen_netbk_idx_release(netbk, pending_idx); | |
1010 | for (j = start; j < i; j++) { | |
1011 | pending_idx = (unsigned long)shinfo->frags[i].page; | |
1012 | xen_netbk_idx_release(netbk, pending_idx); | |
1013 | } | |
1014 | ||
1015 | /* Remember the error: invalidate all subsequent fragments. */ | |
1016 | err = newerr; | |
1017 | } | |
1018 | ||
1019 | *gopp = gop + 1; | |
1020 | return err; | |
1021 | } | |
1022 | ||
1023 | static void xen_netbk_fill_frags(struct xen_netbk *netbk, struct sk_buff *skb) | |
1024 | { | |
1025 | struct skb_shared_info *shinfo = skb_shinfo(skb); | |
1026 | int nr_frags = shinfo->nr_frags; | |
1027 | int i; | |
1028 | ||
1029 | for (i = 0; i < nr_frags; i++) { | |
1030 | skb_frag_t *frag = shinfo->frags + i; | |
1031 | struct xen_netif_tx_request *txp; | |
1032 | unsigned long pending_idx; | |
1033 | ||
1034 | pending_idx = (unsigned long)frag->page; | |
1035 | ||
1036 | txp = &netbk->pending_tx_info[pending_idx].req; | |
1037 | frag->page = virt_to_page(idx_to_kaddr(netbk, pending_idx)); | |
1038 | frag->size = txp->size; | |
1039 | frag->page_offset = txp->offset; | |
1040 | ||
1041 | skb->len += txp->size; | |
1042 | skb->data_len += txp->size; | |
1043 | skb->truesize += txp->size; | |
1044 | ||
1045 | /* Take an extra reference to offset xen_netbk_idx_release */ | |
1046 | get_page(netbk->mmap_pages[pending_idx]); | |
1047 | xen_netbk_idx_release(netbk, pending_idx); | |
1048 | } | |
1049 | } | |
1050 | ||
1051 | static int xen_netbk_get_extras(struct xenvif *vif, | |
1052 | struct xen_netif_extra_info *extras, | |
1053 | int work_to_do) | |
1054 | { | |
1055 | struct xen_netif_extra_info extra; | |
1056 | RING_IDX cons = vif->tx.req_cons; | |
1057 | ||
1058 | do { | |
1059 | if (unlikely(work_to_do-- <= 0)) { | |
1060 | netdev_dbg(vif->dev, "Missing extra info\n"); | |
1061 | return -EBADR; | |
1062 | } | |
1063 | ||
1064 | memcpy(&extra, RING_GET_REQUEST(&vif->tx, cons), | |
1065 | sizeof(extra)); | |
1066 | if (unlikely(!extra.type || | |
1067 | extra.type >= XEN_NETIF_EXTRA_TYPE_MAX)) { | |
1068 | vif->tx.req_cons = ++cons; | |
1069 | netdev_dbg(vif->dev, | |
1070 | "Invalid extra type: %d\n", extra.type); | |
1071 | return -EINVAL; | |
1072 | } | |
1073 | ||
1074 | memcpy(&extras[extra.type - 1], &extra, sizeof(extra)); | |
1075 | vif->tx.req_cons = ++cons; | |
1076 | } while (extra.flags & XEN_NETIF_EXTRA_FLAG_MORE); | |
1077 | ||
1078 | return work_to_do; | |
1079 | } | |
1080 | ||
1081 | static int netbk_set_skb_gso(struct xenvif *vif, | |
1082 | struct sk_buff *skb, | |
1083 | struct xen_netif_extra_info *gso) | |
1084 | { | |
1085 | if (!gso->u.gso.size) { | |
1086 | netdev_dbg(vif->dev, "GSO size must not be zero.\n"); | |
1087 | return -EINVAL; | |
1088 | } | |
1089 | ||
1090 | /* Currently only TCPv4 S.O. is supported. */ | |
1091 | if (gso->u.gso.type != XEN_NETIF_GSO_TYPE_TCPV4) { | |
1092 | netdev_dbg(vif->dev, "Bad GSO type %d.\n", gso->u.gso.type); | |
1093 | return -EINVAL; | |
1094 | } | |
1095 | ||
1096 | skb_shinfo(skb)->gso_size = gso->u.gso.size; | |
1097 | skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4; | |
1098 | ||
1099 | /* Header must be checked, and gso_segs computed. */ | |
1100 | skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; | |
1101 | skb_shinfo(skb)->gso_segs = 0; | |
1102 | ||
1103 | return 0; | |
1104 | } | |
1105 | ||
1106 | static int checksum_setup(struct xenvif *vif, struct sk_buff *skb) | |
1107 | { | |
1108 | struct iphdr *iph; | |
1109 | unsigned char *th; | |
1110 | int err = -EPROTO; | |
1111 | int recalculate_partial_csum = 0; | |
1112 | ||
1113 | /* | |
1114 | * A GSO SKB must be CHECKSUM_PARTIAL. However some buggy | |
1115 | * peers can fail to set NETRXF_csum_blank when sending a GSO | |
1116 | * frame. In this case force the SKB to CHECKSUM_PARTIAL and | |
1117 | * recalculate the partial checksum. | |
1118 | */ | |
1119 | if (skb->ip_summed != CHECKSUM_PARTIAL && skb_is_gso(skb)) { | |
1120 | vif->rx_gso_checksum_fixup++; | |
1121 | skb->ip_summed = CHECKSUM_PARTIAL; | |
1122 | recalculate_partial_csum = 1; | |
1123 | } | |
1124 | ||
1125 | /* A non-CHECKSUM_PARTIAL SKB does not require setup. */ | |
1126 | if (skb->ip_summed != CHECKSUM_PARTIAL) | |
1127 | return 0; | |
1128 | ||
1129 | if (skb->protocol != htons(ETH_P_IP)) | |
1130 | goto out; | |
1131 | ||
1132 | iph = (void *)skb->data; | |
1133 | th = skb->data + 4 * iph->ihl; | |
1134 | if (th >= skb_tail_pointer(skb)) | |
1135 | goto out; | |
1136 | ||
1137 | skb->csum_start = th - skb->head; | |
1138 | switch (iph->protocol) { | |
1139 | case IPPROTO_TCP: | |
1140 | skb->csum_offset = offsetof(struct tcphdr, check); | |
1141 | ||
1142 | if (recalculate_partial_csum) { | |
1143 | struct tcphdr *tcph = (struct tcphdr *)th; | |
1144 | tcph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, | |
1145 | skb->len - iph->ihl*4, | |
1146 | IPPROTO_TCP, 0); | |
1147 | } | |
1148 | break; | |
1149 | case IPPROTO_UDP: | |
1150 | skb->csum_offset = offsetof(struct udphdr, check); | |
1151 | ||
1152 | if (recalculate_partial_csum) { | |
1153 | struct udphdr *udph = (struct udphdr *)th; | |
1154 | udph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, | |
1155 | skb->len - iph->ihl*4, | |
1156 | IPPROTO_UDP, 0); | |
1157 | } | |
1158 | break; | |
1159 | default: | |
1160 | if (net_ratelimit()) | |
1161 | netdev_err(vif->dev, | |
1162 | "Attempting to checksum a non-TCP/UDP packet, dropping a protocol %d packet\n", | |
1163 | iph->protocol); | |
1164 | goto out; | |
1165 | } | |
1166 | ||
1167 | if ((th + skb->csum_offset + 2) > skb_tail_pointer(skb)) | |
1168 | goto out; | |
1169 | ||
1170 | err = 0; | |
1171 | ||
1172 | out: | |
1173 | return err; | |
1174 | } | |
1175 | ||
1176 | static bool tx_credit_exceeded(struct xenvif *vif, unsigned size) | |
1177 | { | |
1178 | unsigned long now = jiffies; | |
1179 | unsigned long next_credit = | |
1180 | vif->credit_timeout.expires + | |
1181 | msecs_to_jiffies(vif->credit_usec / 1000); | |
1182 | ||
1183 | /* Timer could already be pending in rare cases. */ | |
1184 | if (timer_pending(&vif->credit_timeout)) | |
1185 | return true; | |
1186 | ||
1187 | /* Passed the point where we can replenish credit? */ | |
1188 | if (time_after_eq(now, next_credit)) { | |
1189 | vif->credit_timeout.expires = now; | |
1190 | tx_add_credit(vif); | |
1191 | } | |
1192 | ||
1193 | /* Still too big to send right now? Set a callback. */ | |
1194 | if (size > vif->remaining_credit) { | |
1195 | vif->credit_timeout.data = | |
1196 | (unsigned long)vif; | |
1197 | vif->credit_timeout.function = | |
1198 | tx_credit_callback; | |
1199 | mod_timer(&vif->credit_timeout, | |
1200 | next_credit); | |
1201 | ||
1202 | return true; | |
1203 | } | |
1204 | ||
1205 | return false; | |
1206 | } | |
1207 | ||
1208 | static unsigned xen_netbk_tx_build_gops(struct xen_netbk *netbk) | |
1209 | { | |
1210 | struct gnttab_copy *gop = netbk->tx_copy_ops, *request_gop; | |
1211 | struct sk_buff *skb; | |
1212 | int ret; | |
1213 | ||
1214 | while (((nr_pending_reqs(netbk) + MAX_SKB_FRAGS) < MAX_PENDING_REQS) && | |
1215 | !list_empty(&netbk->net_schedule_list)) { | |
1216 | struct xenvif *vif; | |
1217 | struct xen_netif_tx_request txreq; | |
1218 | struct xen_netif_tx_request txfrags[MAX_SKB_FRAGS]; | |
1219 | struct page *page; | |
1220 | struct xen_netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX-1]; | |
1221 | u16 pending_idx; | |
1222 | RING_IDX idx; | |
1223 | int work_to_do; | |
1224 | unsigned int data_len; | |
1225 | pending_ring_idx_t index; | |
1226 | ||
1227 | /* Get a netif from the list with work to do. */ | |
1228 | vif = poll_net_schedule_list(netbk); | |
1229 | if (!vif) | |
1230 | continue; | |
1231 | ||
1232 | RING_FINAL_CHECK_FOR_REQUESTS(&vif->tx, work_to_do); | |
1233 | if (!work_to_do) { | |
1234 | xenvif_put(vif); | |
1235 | continue; | |
1236 | } | |
1237 | ||
1238 | idx = vif->tx.req_cons; | |
1239 | rmb(); /* Ensure that we see the request before we copy it. */ | |
1240 | memcpy(&txreq, RING_GET_REQUEST(&vif->tx, idx), sizeof(txreq)); | |
1241 | ||
1242 | /* Credit-based scheduling. */ | |
1243 | if (txreq.size > vif->remaining_credit && | |
1244 | tx_credit_exceeded(vif, txreq.size)) { | |
1245 | xenvif_put(vif); | |
1246 | continue; | |
1247 | } | |
1248 | ||
1249 | vif->remaining_credit -= txreq.size; | |
1250 | ||
1251 | work_to_do--; | |
1252 | vif->tx.req_cons = ++idx; | |
1253 | ||
1254 | memset(extras, 0, sizeof(extras)); | |
1255 | if (txreq.flags & XEN_NETTXF_extra_info) { | |
1256 | work_to_do = xen_netbk_get_extras(vif, extras, | |
1257 | work_to_do); | |
1258 | idx = vif->tx.req_cons; | |
1259 | if (unlikely(work_to_do < 0)) { | |
1260 | netbk_tx_err(vif, &txreq, idx); | |
1261 | continue; | |
1262 | } | |
1263 | } | |
1264 | ||
1265 | ret = netbk_count_requests(vif, &txreq, txfrags, work_to_do); | |
1266 | if (unlikely(ret < 0)) { | |
1267 | netbk_tx_err(vif, &txreq, idx - ret); | |
1268 | continue; | |
1269 | } | |
1270 | idx += ret; | |
1271 | ||
1272 | if (unlikely(txreq.size < ETH_HLEN)) { | |
1273 | netdev_dbg(vif->dev, | |
1274 | "Bad packet size: %d\n", txreq.size); | |
1275 | netbk_tx_err(vif, &txreq, idx); | |
1276 | continue; | |
1277 | } | |
1278 | ||
1279 | /* No crossing a page as the payload mustn't fragment. */ | |
1280 | if (unlikely((txreq.offset + txreq.size) > PAGE_SIZE)) { | |
1281 | netdev_dbg(vif->dev, | |
1282 | "txreq.offset: %x, size: %u, end: %lu\n", | |
1283 | txreq.offset, txreq.size, | |
1284 | (txreq.offset&~PAGE_MASK) + txreq.size); | |
1285 | netbk_tx_err(vif, &txreq, idx); | |
1286 | continue; | |
1287 | } | |
1288 | ||
1289 | index = pending_index(netbk->pending_cons); | |
1290 | pending_idx = netbk->pending_ring[index]; | |
1291 | ||
1292 | data_len = (txreq.size > PKT_PROT_LEN && | |
1293 | ret < MAX_SKB_FRAGS) ? | |
1294 | PKT_PROT_LEN : txreq.size; | |
1295 | ||
1296 | skb = alloc_skb(data_len + NET_SKB_PAD + NET_IP_ALIGN, | |
1297 | GFP_ATOMIC | __GFP_NOWARN); | |
1298 | if (unlikely(skb == NULL)) { | |
1299 | netdev_dbg(vif->dev, | |
1300 | "Can't allocate a skb in start_xmit.\n"); | |
1301 | netbk_tx_err(vif, &txreq, idx); | |
1302 | break; | |
1303 | } | |
1304 | ||
1305 | /* Packets passed to netif_rx() must have some headroom. */ | |
1306 | skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN); | |
1307 | ||
1308 | if (extras[XEN_NETIF_EXTRA_TYPE_GSO - 1].type) { | |
1309 | struct xen_netif_extra_info *gso; | |
1310 | gso = &extras[XEN_NETIF_EXTRA_TYPE_GSO - 1]; | |
1311 | ||
1312 | if (netbk_set_skb_gso(vif, skb, gso)) { | |
1313 | kfree_skb(skb); | |
1314 | netbk_tx_err(vif, &txreq, idx); | |
1315 | continue; | |
1316 | } | |
1317 | } | |
1318 | ||
1319 | /* XXX could copy straight to head */ | |
1320 | page = xen_netbk_alloc_page(netbk, skb, pending_idx); | |
1321 | if (!page) { | |
1322 | kfree_skb(skb); | |
1323 | netbk_tx_err(vif, &txreq, idx); | |
1324 | continue; | |
1325 | } | |
1326 | ||
1327 | netbk->mmap_pages[pending_idx] = page; | |
1328 | ||
1329 | gop->source.u.ref = txreq.gref; | |
1330 | gop->source.domid = vif->domid; | |
1331 | gop->source.offset = txreq.offset; | |
1332 | ||
1333 | gop->dest.u.gmfn = virt_to_mfn(page_address(page)); | |
1334 | gop->dest.domid = DOMID_SELF; | |
1335 | gop->dest.offset = txreq.offset; | |
1336 | ||
1337 | gop->len = txreq.size; | |
1338 | gop->flags = GNTCOPY_source_gref; | |
1339 | ||
1340 | gop++; | |
1341 | ||
1342 | memcpy(&netbk->pending_tx_info[pending_idx].req, | |
1343 | &txreq, sizeof(txreq)); | |
1344 | netbk->pending_tx_info[pending_idx].vif = vif; | |
1345 | *((u16 *)skb->data) = pending_idx; | |
1346 | ||
1347 | __skb_put(skb, data_len); | |
1348 | ||
1349 | skb_shinfo(skb)->nr_frags = ret; | |
1350 | if (data_len < txreq.size) { | |
1351 | skb_shinfo(skb)->nr_frags++; | |
1352 | skb_shinfo(skb)->frags[0].page = | |
1353 | (void *)(unsigned long)pending_idx; | |
1354 | } else { | |
1355 | /* Discriminate from any valid pending_idx value. */ | |
1356 | skb_shinfo(skb)->frags[0].page = (void *)~0UL; | |
1357 | } | |
1358 | ||
1359 | __skb_queue_tail(&netbk->tx_queue, skb); | |
1360 | ||
1361 | netbk->pending_cons++; | |
1362 | ||
1363 | request_gop = xen_netbk_get_requests(netbk, vif, | |
1364 | skb, txfrags, gop); | |
1365 | if (request_gop == NULL) { | |
1366 | kfree_skb(skb); | |
1367 | netbk_tx_err(vif, &txreq, idx); | |
1368 | continue; | |
1369 | } | |
1370 | gop = request_gop; | |
1371 | ||
1372 | vif->tx.req_cons = idx; | |
1373 | xen_netbk_check_rx_xenvif(vif); | |
1374 | ||
1375 | if ((gop-netbk->tx_copy_ops) >= ARRAY_SIZE(netbk->tx_copy_ops)) | |
1376 | break; | |
1377 | } | |
1378 | ||
1379 | return gop - netbk->tx_copy_ops; | |
1380 | } | |
1381 | ||
1382 | static void xen_netbk_tx_submit(struct xen_netbk *netbk) | |
1383 | { | |
1384 | struct gnttab_copy *gop = netbk->tx_copy_ops; | |
1385 | struct sk_buff *skb; | |
1386 | ||
1387 | while ((skb = __skb_dequeue(&netbk->tx_queue)) != NULL) { | |
1388 | struct xen_netif_tx_request *txp; | |
1389 | struct xenvif *vif; | |
1390 | u16 pending_idx; | |
1391 | unsigned data_len; | |
1392 | ||
1393 | pending_idx = *((u16 *)skb->data); | |
1394 | vif = netbk->pending_tx_info[pending_idx].vif; | |
1395 | txp = &netbk->pending_tx_info[pending_idx].req; | |
1396 | ||
1397 | /* Check the remap error code. */ | |
1398 | if (unlikely(xen_netbk_tx_check_gop(netbk, skb, &gop))) { | |
1399 | netdev_dbg(vif->dev, "netback grant failed.\n"); | |
1400 | skb_shinfo(skb)->nr_frags = 0; | |
1401 | kfree_skb(skb); | |
1402 | continue; | |
1403 | } | |
1404 | ||
1405 | data_len = skb->len; | |
1406 | memcpy(skb->data, | |
1407 | (void *)(idx_to_kaddr(netbk, pending_idx)|txp->offset), | |
1408 | data_len); | |
1409 | if (data_len < txp->size) { | |
1410 | /* Append the packet payload as a fragment. */ | |
1411 | txp->offset += data_len; | |
1412 | txp->size -= data_len; | |
1413 | } else { | |
1414 | /* Schedule a response immediately. */ | |
1415 | xen_netbk_idx_release(netbk, pending_idx); | |
1416 | } | |
1417 | ||
1418 | if (txp->flags & XEN_NETTXF_csum_blank) | |
1419 | skb->ip_summed = CHECKSUM_PARTIAL; | |
1420 | else if (txp->flags & XEN_NETTXF_data_validated) | |
1421 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
1422 | ||
1423 | xen_netbk_fill_frags(netbk, skb); | |
1424 | ||
1425 | /* | |
1426 | * If the initial fragment was < PKT_PROT_LEN then | |
1427 | * pull through some bytes from the other fragments to | |
1428 | * increase the linear region to PKT_PROT_LEN bytes. | |
1429 | */ | |
1430 | if (skb_headlen(skb) < PKT_PROT_LEN && skb_is_nonlinear(skb)) { | |
1431 | int target = min_t(int, skb->len, PKT_PROT_LEN); | |
1432 | __pskb_pull_tail(skb, target - skb_headlen(skb)); | |
1433 | } | |
1434 | ||
1435 | skb->dev = vif->dev; | |
1436 | skb->protocol = eth_type_trans(skb, skb->dev); | |
1437 | ||
1438 | if (checksum_setup(vif, skb)) { | |
1439 | netdev_dbg(vif->dev, | |
1440 | "Can't setup checksum in net_tx_action\n"); | |
1441 | kfree_skb(skb); | |
1442 | continue; | |
1443 | } | |
1444 | ||
1445 | vif->dev->stats.rx_bytes += skb->len; | |
1446 | vif->dev->stats.rx_packets++; | |
1447 | ||
1448 | xenvif_receive_skb(vif, skb); | |
1449 | } | |
1450 | } | |
1451 | ||
1452 | /* Called after netfront has transmitted */ | |
1453 | static void xen_netbk_tx_action(struct xen_netbk *netbk) | |
1454 | { | |
1455 | unsigned nr_gops; | |
1456 | int ret; | |
1457 | ||
1458 | nr_gops = xen_netbk_tx_build_gops(netbk); | |
1459 | ||
1460 | if (nr_gops == 0) | |
1461 | return; | |
1462 | ret = HYPERVISOR_grant_table_op(GNTTABOP_copy, | |
1463 | netbk->tx_copy_ops, nr_gops); | |
1464 | BUG_ON(ret); | |
1465 | ||
1466 | xen_netbk_tx_submit(netbk); | |
1467 | ||
1468 | } | |
1469 | ||
1470 | static void xen_netbk_idx_release(struct xen_netbk *netbk, u16 pending_idx) | |
1471 | { | |
1472 | struct xenvif *vif; | |
1473 | struct pending_tx_info *pending_tx_info; | |
1474 | pending_ring_idx_t index; | |
1475 | ||
1476 | /* Already complete? */ | |
1477 | if (netbk->mmap_pages[pending_idx] == NULL) | |
1478 | return; | |
1479 | ||
1480 | pending_tx_info = &netbk->pending_tx_info[pending_idx]; | |
1481 | ||
1482 | vif = pending_tx_info->vif; | |
1483 | ||
1484 | make_tx_response(vif, &pending_tx_info->req, XEN_NETIF_RSP_OKAY); | |
1485 | ||
1486 | index = pending_index(netbk->pending_prod++); | |
1487 | netbk->pending_ring[index] = pending_idx; | |
1488 | ||
1489 | xenvif_put(vif); | |
1490 | ||
1491 | netbk->mmap_pages[pending_idx]->mapping = 0; | |
1492 | put_page(netbk->mmap_pages[pending_idx]); | |
1493 | netbk->mmap_pages[pending_idx] = NULL; | |
1494 | } | |
1495 | ||
1496 | static void make_tx_response(struct xenvif *vif, | |
1497 | struct xen_netif_tx_request *txp, | |
1498 | s8 st) | |
1499 | { | |
1500 | RING_IDX i = vif->tx.rsp_prod_pvt; | |
1501 | struct xen_netif_tx_response *resp; | |
1502 | int notify; | |
1503 | ||
1504 | resp = RING_GET_RESPONSE(&vif->tx, i); | |
1505 | resp->id = txp->id; | |
1506 | resp->status = st; | |
1507 | ||
1508 | if (txp->flags & XEN_NETTXF_extra_info) | |
1509 | RING_GET_RESPONSE(&vif->tx, ++i)->status = XEN_NETIF_RSP_NULL; | |
1510 | ||
1511 | vif->tx.rsp_prod_pvt = ++i; | |
1512 | RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&vif->tx, notify); | |
1513 | if (notify) | |
1514 | notify_remote_via_irq(vif->irq); | |
1515 | } | |
1516 | ||
1517 | static struct xen_netif_rx_response *make_rx_response(struct xenvif *vif, | |
1518 | u16 id, | |
1519 | s8 st, | |
1520 | u16 offset, | |
1521 | u16 size, | |
1522 | u16 flags) | |
1523 | { | |
1524 | RING_IDX i = vif->rx.rsp_prod_pvt; | |
1525 | struct xen_netif_rx_response *resp; | |
1526 | ||
1527 | resp = RING_GET_RESPONSE(&vif->rx, i); | |
1528 | resp->offset = offset; | |
1529 | resp->flags = flags; | |
1530 | resp->id = id; | |
1531 | resp->status = (s16)size; | |
1532 | if (st < 0) | |
1533 | resp->status = (s16)st; | |
1534 | ||
1535 | vif->rx.rsp_prod_pvt = ++i; | |
1536 | ||
1537 | return resp; | |
1538 | } | |
1539 | ||
1540 | static inline int rx_work_todo(struct xen_netbk *netbk) | |
1541 | { | |
1542 | return !skb_queue_empty(&netbk->rx_queue); | |
1543 | } | |
1544 | ||
1545 | static inline int tx_work_todo(struct xen_netbk *netbk) | |
1546 | { | |
1547 | ||
1548 | if (((nr_pending_reqs(netbk) + MAX_SKB_FRAGS) < MAX_PENDING_REQS) && | |
1549 | !list_empty(&netbk->net_schedule_list)) | |
1550 | return 1; | |
1551 | ||
1552 | return 0; | |
1553 | } | |
1554 | ||
1555 | static int xen_netbk_kthread(void *data) | |
1556 | { | |
1557 | struct xen_netbk *netbk = data; | |
1558 | while (!kthread_should_stop()) { | |
1559 | wait_event_interruptible(netbk->wq, | |
1560 | rx_work_todo(netbk) || | |
1561 | tx_work_todo(netbk) || | |
1562 | kthread_should_stop()); | |
1563 | cond_resched(); | |
1564 | ||
1565 | if (kthread_should_stop()) | |
1566 | break; | |
1567 | ||
1568 | if (rx_work_todo(netbk)) | |
1569 | xen_netbk_rx_action(netbk); | |
1570 | ||
1571 | if (tx_work_todo(netbk)) | |
1572 | xen_netbk_tx_action(netbk); | |
1573 | } | |
1574 | ||
1575 | return 0; | |
1576 | } | |
1577 | ||
1578 | void xen_netbk_unmap_frontend_rings(struct xenvif *vif) | |
1579 | { | |
1580 | struct gnttab_unmap_grant_ref op; | |
1581 | ||
1582 | if (vif->tx.sring) { | |
1583 | gnttab_set_unmap_op(&op, (unsigned long)vif->tx_comms_area->addr, | |
1584 | GNTMAP_host_map, vif->tx_shmem_handle); | |
1585 | ||
1586 | if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1)) | |
1587 | BUG(); | |
1588 | } | |
1589 | ||
1590 | if (vif->rx.sring) { | |
1591 | gnttab_set_unmap_op(&op, (unsigned long)vif->rx_comms_area->addr, | |
1592 | GNTMAP_host_map, vif->rx_shmem_handle); | |
1593 | ||
1594 | if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1)) | |
1595 | BUG(); | |
1596 | } | |
1597 | if (vif->rx_comms_area) | |
1598 | free_vm_area(vif->rx_comms_area); | |
1599 | if (vif->tx_comms_area) | |
1600 | free_vm_area(vif->tx_comms_area); | |
1601 | } | |
1602 | ||
1603 | int xen_netbk_map_frontend_rings(struct xenvif *vif, | |
1604 | grant_ref_t tx_ring_ref, | |
1605 | grant_ref_t rx_ring_ref) | |
1606 | { | |
1607 | struct gnttab_map_grant_ref op; | |
1608 | struct xen_netif_tx_sring *txs; | |
1609 | struct xen_netif_rx_sring *rxs; | |
1610 | ||
1611 | int err = -ENOMEM; | |
1612 | ||
1613 | vif->tx_comms_area = alloc_vm_area(PAGE_SIZE); | |
1614 | if (vif->tx_comms_area == NULL) | |
1615 | goto err; | |
1616 | ||
1617 | vif->rx_comms_area = alloc_vm_area(PAGE_SIZE); | |
1618 | if (vif->rx_comms_area == NULL) | |
1619 | goto err; | |
1620 | ||
1621 | gnttab_set_map_op(&op, (unsigned long)vif->tx_comms_area->addr, | |
1622 | GNTMAP_host_map, tx_ring_ref, vif->domid); | |
1623 | ||
1624 | if (HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1)) | |
1625 | BUG(); | |
1626 | ||
1627 | if (op.status) { | |
1628 | netdev_warn(vif->dev, | |
1629 | "failed to map tx ring. err=%d status=%d\n", | |
1630 | err, op.status); | |
1631 | err = op.status; | |
1632 | goto err; | |
1633 | } | |
1634 | ||
1635 | vif->tx_shmem_ref = tx_ring_ref; | |
1636 | vif->tx_shmem_handle = op.handle; | |
1637 | ||
1638 | txs = (struct xen_netif_tx_sring *)vif->tx_comms_area->addr; | |
1639 | BACK_RING_INIT(&vif->tx, txs, PAGE_SIZE); | |
1640 | ||
1641 | gnttab_set_map_op(&op, (unsigned long)vif->rx_comms_area->addr, | |
1642 | GNTMAP_host_map, rx_ring_ref, vif->domid); | |
1643 | ||
1644 | if (HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1)) | |
1645 | BUG(); | |
1646 | ||
1647 | if (op.status) { | |
1648 | netdev_warn(vif->dev, | |
1649 | "failed to map rx ring. err=%d status=%d\n", | |
1650 | err, op.status); | |
1651 | err = op.status; | |
1652 | goto err; | |
1653 | } | |
1654 | ||
1655 | vif->rx_shmem_ref = rx_ring_ref; | |
1656 | vif->rx_shmem_handle = op.handle; | |
1657 | vif->rx_req_cons_peek = 0; | |
1658 | ||
1659 | rxs = (struct xen_netif_rx_sring *)vif->rx_comms_area->addr; | |
1660 | BACK_RING_INIT(&vif->rx, rxs, PAGE_SIZE); | |
1661 | ||
1662 | return 0; | |
1663 | ||
1664 | err: | |
1665 | xen_netbk_unmap_frontend_rings(vif); | |
1666 | return err; | |
1667 | } | |
1668 | ||
1669 | static int __init netback_init(void) | |
1670 | { | |
1671 | int i; | |
1672 | int rc = 0; | |
1673 | int group; | |
1674 | ||
1675 | if (!xen_pv_domain()) | |
1676 | return -ENODEV; | |
1677 | ||
1678 | xen_netbk_group_nr = num_online_cpus(); | |
1679 | xen_netbk = vzalloc(sizeof(struct xen_netbk) * xen_netbk_group_nr); | |
1680 | if (!xen_netbk) { | |
1681 | printk(KERN_ALERT "%s: out of memory\n", __func__); | |
1682 | return -ENOMEM; | |
1683 | } | |
1684 | ||
1685 | for (group = 0; group < xen_netbk_group_nr; group++) { | |
1686 | struct xen_netbk *netbk = &xen_netbk[group]; | |
1687 | skb_queue_head_init(&netbk->rx_queue); | |
1688 | skb_queue_head_init(&netbk->tx_queue); | |
1689 | ||
1690 | init_timer(&netbk->net_timer); | |
1691 | netbk->net_timer.data = (unsigned long)netbk; | |
1692 | netbk->net_timer.function = xen_netbk_alarm; | |
1693 | ||
1694 | netbk->pending_cons = 0; | |
1695 | netbk->pending_prod = MAX_PENDING_REQS; | |
1696 | for (i = 0; i < MAX_PENDING_REQS; i++) | |
1697 | netbk->pending_ring[i] = i; | |
1698 | ||
1699 | init_waitqueue_head(&netbk->wq); | |
1700 | netbk->task = kthread_create(xen_netbk_kthread, | |
1701 | (void *)netbk, | |
1702 | "netback/%u", group); | |
1703 | ||
1704 | if (IS_ERR(netbk->task)) { | |
1705 | printk(KERN_ALERT "kthread_run() fails at netback\n"); | |
1706 | del_timer(&netbk->net_timer); | |
1707 | rc = PTR_ERR(netbk->task); | |
1708 | goto failed_init; | |
1709 | } | |
1710 | ||
1711 | kthread_bind(netbk->task, group); | |
1712 | ||
1713 | INIT_LIST_HEAD(&netbk->net_schedule_list); | |
1714 | ||
1715 | spin_lock_init(&netbk->net_schedule_list_lock); | |
1716 | ||
1717 | atomic_set(&netbk->netfront_count, 0); | |
1718 | ||
1719 | wake_up_process(netbk->task); | |
1720 | } | |
1721 | ||
1722 | rc = xenvif_xenbus_init(); | |
1723 | if (rc) | |
1724 | goto failed_init; | |
1725 | ||
1726 | return 0; | |
1727 | ||
1728 | failed_init: | |
1729 | while (--group >= 0) { | |
1730 | struct xen_netbk *netbk = &xen_netbk[group]; | |
1731 | for (i = 0; i < MAX_PENDING_REQS; i++) { | |
1732 | if (netbk->mmap_pages[i]) | |
1733 | __free_page(netbk->mmap_pages[i]); | |
1734 | } | |
1735 | del_timer(&netbk->net_timer); | |
1736 | kthread_stop(netbk->task); | |
1737 | } | |
1738 | vfree(xen_netbk); | |
1739 | return rc; | |
1740 | ||
1741 | } | |
1742 | ||
1743 | module_init(netback_init); | |
1744 | ||
1745 | MODULE_LICENSE("Dual BSD/GPL"); |