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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 | ||
ca981633 | 43 | #include <xen/xen.h> |
f942dc25 IC |
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 | ||
ea066ad1 IC |
64 | /* Discriminate from any valid pending_idx value. */ |
65 | #define INVALID_PENDING_IDX 0xFFFF | |
66 | ||
f942dc25 IC |
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 | ||
7d5145d8 MD |
150 | static void xen_netbk_idx_release(struct xen_netbk *netbk, u16 pending_idx, |
151 | u8 status); | |
f942dc25 IC |
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, | |
ea066ad1 | 163 | u16 idx) |
f942dc25 IC |
164 | { |
165 | return page_to_pfn(netbk->mmap_pages[idx]); | |
166 | } | |
167 | ||
168 | static inline unsigned long idx_to_kaddr(struct xen_netbk *netbk, | |
ea066ad1 | 169 | u16 idx) |
f942dc25 IC |
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 | ||
ea066ad1 IC |
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 | ||
f942dc25 IC |
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 | ||
e26b203e | 330 | count = DIV_ROUND_UP(skb_headlen(skb), PAGE_SIZE); |
f942dc25 IC |
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++) { | |
9e903e08 | 338 | unsigned long size = skb_frag_size(&skb_shinfo(skb)->frags[i]); |
6a8ed462 | 339 | unsigned long offset = skb_shinfo(skb)->frags[i].page_offset; |
f942dc25 | 340 | unsigned long bytes; |
6a8ed462 IC |
341 | |
342 | offset &= ~PAGE_MASK; | |
343 | ||
f942dc25 | 344 | while (size > 0) { |
6a8ed462 | 345 | BUG_ON(offset >= PAGE_SIZE); |
f942dc25 IC |
346 | BUG_ON(copy_off > MAX_BUFFER_OFFSET); |
347 | ||
6a8ed462 IC |
348 | bytes = PAGE_SIZE - offset; |
349 | ||
350 | if (bytes > size) | |
351 | bytes = size; | |
352 | ||
353 | if (start_new_rx_buffer(copy_off, bytes, 0)) { | |
f942dc25 IC |
354 | count++; |
355 | copy_off = 0; | |
356 | } | |
357 | ||
f942dc25 IC |
358 | if (copy_off + bytes > MAX_BUFFER_OFFSET) |
359 | bytes = MAX_BUFFER_OFFSET - copy_off; | |
360 | ||
361 | copy_off += bytes; | |
6a8ed462 IC |
362 | |
363 | offset += bytes; | |
f942dc25 | 364 | size -= bytes; |
6a8ed462 IC |
365 | |
366 | if (offset == PAGE_SIZE) | |
367 | offset = 0; | |
f942dc25 IC |
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 | /* | |
e34c0246 | 413 | * These variables are used iff get_page_ext returns true, |
f942dc25 IC |
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. */ | |
6a8ed462 | 421 | BUG_ON(size + offset > PAGE_SIZE<<compound_order(page)); |
f942dc25 IC |
422 | |
423 | meta = npo->meta + npo->meta_prod - 1; | |
424 | ||
6a8ed462 IC |
425 | /* Skip unused frames from start of page */ |
426 | page += offset >> PAGE_SHIFT; | |
427 | offset &= ~PAGE_MASK; | |
428 | ||
f942dc25 | 429 | while (size > 0) { |
6a8ed462 | 430 | BUG_ON(offset >= PAGE_SIZE); |
f942dc25 IC |
431 | BUG_ON(npo->copy_off > MAX_BUFFER_OFFSET); |
432 | ||
6a8ed462 IC |
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)) { | |
f942dc25 IC |
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 | ||
f942dc25 IC |
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 | ||
6a8ed462 IC |
480 | /* Next frame */ |
481 | if (offset == PAGE_SIZE && size) { | |
482 | BUG_ON(!PageCompound(page)); | |
483 | page++; | |
484 | offset = 0; | |
485 | } | |
486 | ||
f942dc25 IC |
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, | |
ea066ad1 | 559 | skb_frag_page(&skb_shinfo(skb)->frags[i]), |
9e903e08 | 560 | skb_frag_size(&skb_shinfo(skb)->frags[i]), |
f942dc25 IC |
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)); | |
c571898f | 670 | gnttab_batch_copy(netbk->grant_copy_op, npo.copy_prod); |
f942dc25 IC |
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); | |
b9149729 | 883 | if (cons == end) |
f942dc25 IC |
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 | ||
48856286 IC |
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); | |
896 | xenvif_put(vif); | |
897 | } | |
898 | ||
f942dc25 IC |
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) { | |
48856286 IC |
912 | netdev_err(vif->dev, "Need more frags\n"); |
913 | netbk_fatal_tx_err(vif); | |
f942dc25 IC |
914 | return -frags; |
915 | } | |
916 | ||
917 | if (unlikely(frags >= MAX_SKB_FRAGS)) { | |
48856286 IC |
918 | netdev_err(vif->dev, "Too many frags\n"); |
919 | netbk_fatal_tx_err(vif); | |
f942dc25 IC |
920 | return -frags; |
921 | } | |
922 | ||
923 | memcpy(txp, RING_GET_REQUEST(&vif->tx, cons + frags), | |
924 | sizeof(*txp)); | |
925 | if (txp->size > first->size) { | |
48856286 IC |
926 | netdev_err(vif->dev, "Frag is bigger than frame.\n"); |
927 | netbk_fatal_tx_err(vif); | |
f942dc25 IC |
928 | return -frags; |
929 | } | |
930 | ||
931 | first->size -= txp->size; | |
932 | frags++; | |
933 | ||
934 | if (unlikely((txp->offset + txp->size) > PAGE_SIZE)) { | |
48856286 | 935 | netdev_err(vif->dev, "txp->offset: %x, size: %u\n", |
f942dc25 | 936 | txp->offset, txp->size); |
48856286 | 937 | netbk_fatal_tx_err(vif); |
f942dc25 IC |
938 | return -frags; |
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, | |
ea066ad1 | 946 | u16 pending_idx) |
f942dc25 IC |
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; | |
ea066ad1 | 965 | u16 pending_idx = *((u16 *)skb->data); |
f942dc25 IC |
966 | int i, start; |
967 | ||
968 | /* Skip first skb fragment if it is on same page as header fragment. */ | |
ea066ad1 | 969 | start = (frag_get_pending_idx(&shinfo->frags[0]) == pending_idx); |
f942dc25 IC |
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) | |
4cc7c1cb | 981 | goto err; |
f942dc25 | 982 | |
f942dc25 IC |
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; | |
ea066ad1 | 999 | frag_set_pending_idx(&frags[i], pending_idx); |
f942dc25 IC |
1000 | } |
1001 | ||
1002 | return gop; | |
4cc7c1cb IC |
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; | |
f942dc25 IC |
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; | |
ea066ad1 | 1021 | u16 pending_idx = *((u16 *)skb->data); |
f942dc25 IC |
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; | |
7d5145d8 MD |
1028 | if (unlikely(err)) |
1029 | xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_ERROR); | |
f942dc25 IC |
1030 | |
1031 | /* Skip first skb fragment if it is on same page as header fragment. */ | |
ea066ad1 | 1032 | start = (frag_get_pending_idx(&shinfo->frags[0]) == pending_idx); |
f942dc25 IC |
1033 | |
1034 | for (i = start; i < nr_frags; i++) { | |
1035 | int j, newerr; | |
f942dc25 | 1036 | |
ea066ad1 | 1037 | pending_idx = frag_get_pending_idx(&shinfo->frags[i]); |
f942dc25 IC |
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)) | |
7d5145d8 | 1044 | xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_OKAY); |
f942dc25 IC |
1045 | continue; |
1046 | } | |
1047 | ||
1048 | /* Error on this fragment: respond to client with an error. */ | |
7d5145d8 | 1049 | xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_ERROR); |
f942dc25 IC |
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); | |
7d5145d8 | 1057 | xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_OKAY); |
f942dc25 | 1058 | for (j = start; j < i; j++) { |
5ccb3ea7 | 1059 | pending_idx = frag_get_pending_idx(&shinfo->frags[j]); |
7d5145d8 | 1060 | xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_OKAY); |
f942dc25 IC |
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; | |
ea066ad1 IC |
1080 | struct page *page; |
1081 | u16 pending_idx; | |
f942dc25 | 1082 | |
ea066ad1 | 1083 | pending_idx = frag_get_pending_idx(frag); |
f942dc25 IC |
1084 | |
1085 | txp = &netbk->pending_tx_info[pending_idx].req; | |
ea066ad1 IC |
1086 | page = virt_to_page(idx_to_kaddr(netbk, pending_idx)); |
1087 | __skb_fill_page_desc(skb, i, page, txp->offset, txp->size); | |
f942dc25 IC |
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]); | |
7d5145d8 | 1094 | xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_OKAY); |
f942dc25 IC |
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)) { | |
48856286 IC |
1107 | netdev_err(vif->dev, "Missing extra info\n"); |
1108 | netbk_fatal_tx_err(vif); | |
f942dc25 IC |
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; | |
48856286 | 1117 | netdev_err(vif->dev, |
f942dc25 | 1118 | "Invalid extra type: %d\n", extra.type); |
48856286 | 1119 | netbk_fatal_tx_err(vif); |
f942dc25 IC |
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) { | |
48856286 IC |
1135 | netdev_err(vif->dev, "GSO size must not be zero.\n"); |
1136 | netbk_fatal_tx_err(vif); | |
f942dc25 IC |
1137 | return -EINVAL; |
1138 | } | |
1139 | ||
1140 | /* Currently only TCPv4 S.O. is supported. */ | |
1141 | if (gso->u.gso.type != XEN_NETIF_GSO_TYPE_TCPV4) { | |
48856286 IC |
1142 | netdev_err(vif->dev, "Bad GSO type %d.\n", gso->u.gso.type); |
1143 | netbk_fatal_tx_err(vif); | |
f942dc25 IC |
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); | |
48856286 IC |
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 | */ | |
f942dc25 IC |
1285 | if (!vif) |
1286 | continue; | |
1287 | ||
48856286 IC |
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 | ||
f942dc25 IC |
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; | |
48856286 | 1326 | if (unlikely(work_to_do < 0)) |
f942dc25 | 1327 | continue; |
f942dc25 IC |
1328 | } |
1329 | ||
1330 | ret = netbk_count_requests(vif, &txreq, txfrags, work_to_do); | |
48856286 | 1331 | if (unlikely(ret < 0)) |
f942dc25 | 1332 | continue; |
48856286 | 1333 | |
f942dc25 IC |
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)) { | |
48856286 | 1345 | netdev_err(vif->dev, |
f942dc25 IC |
1346 | "txreq.offset: %x, size: %u, end: %lu\n", |
1347 | txreq.offset, txreq.size, | |
1348 | (txreq.offset&~PAGE_MASK) + txreq.size); | |
48856286 | 1349 | netbk_fatal_tx_err(vif); |
f942dc25 IC |
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)) { | |
48856286 | 1377 | /* Failure in netbk_set_skb_gso is fatal. */ |
f942dc25 | 1378 | kfree_skb(skb); |
f942dc25 IC |
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 | ||
f942dc25 IC |
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++; | |
ea066ad1 IC |
1414 | frag_set_pending_idx(&skb_shinfo(skb)->frags[0], |
1415 | pending_idx); | |
f942dc25 | 1416 | } else { |
ea066ad1 IC |
1417 | frag_set_pending_idx(&skb_shinfo(skb)->frags[0], |
1418 | INVALID_PENDING_IDX); | |
f942dc25 IC |
1419 | } |
1420 | ||
f942dc25 IC |
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 | ||
1e0b6eac AL |
1432 | __skb_queue_tail(&netbk->tx_queue, skb); |
1433 | ||
f942dc25 IC |
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. */ | |
7d5145d8 | 1477 | xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_OKAY); |
f942dc25 IC |
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; | |
f942dc25 IC |
1518 | |
1519 | nr_gops = xen_netbk_tx_build_gops(netbk); | |
1520 | ||
1521 | if (nr_gops == 0) | |
1522 | return; | |
f942dc25 | 1523 | |
c571898f | 1524 | gnttab_batch_copy(netbk->tx_copy_ops, nr_gops); |
f942dc25 | 1525 | |
c571898f | 1526 | xen_netbk_tx_submit(netbk); |
f942dc25 IC |
1527 | } |
1528 | ||
7d5145d8 MD |
1529 | static void xen_netbk_idx_release(struct xen_netbk *netbk, u16 pending_idx, |
1530 | u8 status) | |
f942dc25 IC |
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 | ||
7d5145d8 | 1544 | make_tx_response(vif, &pending_tx_info->req, status); |
f942dc25 IC |
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 | { | |
c9d63699 DV |
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); | |
f942dc25 IC |
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 | { | |
c9d63699 | 1652 | void *addr; |
f942dc25 IC |
1653 | struct xen_netif_tx_sring *txs; |
1654 | struct xen_netif_rx_sring *rxs; | |
1655 | ||
1656 | int err = -ENOMEM; | |
1657 | ||
c9d63699 DV |
1658 | err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(vif), |
1659 | tx_ring_ref, &addr); | |
1660 | if (err) | |
f942dc25 IC |
1661 | goto err; |
1662 | ||
c9d63699 | 1663 | txs = (struct xen_netif_tx_sring *)addr; |
f942dc25 IC |
1664 | BACK_RING_INIT(&vif->tx, txs, PAGE_SIZE); |
1665 | ||
c9d63699 DV |
1666 | err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(vif), |
1667 | rx_ring_ref, &addr); | |
1668 | if (err) | |
f942dc25 | 1669 | goto err; |
f942dc25 | 1670 | |
c9d63699 | 1671 | rxs = (struct xen_netif_rx_sring *)addr; |
f942dc25 IC |
1672 | BACK_RING_INIT(&vif->rx, rxs, PAGE_SIZE); |
1673 | ||
c9d63699 DV |
1674 | vif->rx_req_cons_peek = 0; |
1675 | ||
f942dc25 IC |
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 | ||
2a14b244 | 1689 | if (!xen_domain()) |
f942dc25 IC |
1690 | return -ENODEV; |
1691 | ||
1692 | xen_netbk_group_nr = num_online_cpus(); | |
1693 | xen_netbk = vzalloc(sizeof(struct xen_netbk) * xen_netbk_group_nr); | |
e404decb | 1694 | if (!xen_netbk) |
f942dc25 | 1695 | return -ENOMEM; |
f942dc25 IC |
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)) { | |
6b84bd16 | 1717 | printk(KERN_ALERT "kthread_create() fails at netback\n"); |
f942dc25 IC |
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"); | |
f984cec6 | 1758 | MODULE_ALIAS("xen-backend:vif"); |