Commit | Line | Data |
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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 | ||
e1f00a69 WL |
50 | /* Provide an option to disable split event channels at load time as |
51 | * event channels are limited resource. Split event channels are | |
52 | * enabled by default. | |
53 | */ | |
54 | bool separate_tx_rx_irq = 1; | |
55 | module_param(separate_tx_rx_irq, bool, 0644); | |
56 | ||
2810e5b9 WL |
57 | /* |
58 | * This is the maximum slots a skb can have. If a guest sends a skb | |
59 | * which exceeds this limit it is considered malicious. | |
60 | */ | |
37641494 WL |
61 | #define FATAL_SKB_SLOTS_DEFAULT 20 |
62 | static unsigned int fatal_skb_slots = FATAL_SKB_SLOTS_DEFAULT; | |
63 | module_param(fatal_skb_slots, uint, 0444); | |
64 | ||
65 | /* | |
66 | * To avoid confusion, we define XEN_NETBK_LEGACY_SLOTS_MAX indicating | |
67 | * the maximum slots a valid packet can use. Now this value is defined | |
68 | * to be XEN_NETIF_NR_SLOTS_MIN, which is supposed to be supported by | |
69 | * all backend. | |
70 | */ | |
71 | #define XEN_NETBK_LEGACY_SLOTS_MAX XEN_NETIF_NR_SLOTS_MIN | |
2810e5b9 | 72 | |
2810e5b9 WL |
73 | /* |
74 | * If head != INVALID_PENDING_RING_IDX, it means this tx request is head of | |
75 | * one or more merged tx requests, otherwise it is the continuation of | |
76 | * previous tx request. | |
77 | */ | |
b3f980bd | 78 | static inline int pending_tx_is_head(struct xenvif *vif, RING_IDX idx) |
f942dc25 | 79 | { |
b3f980bd | 80 | return vif->pending_tx_info[idx].head != INVALID_PENDING_RING_IDX; |
f942dc25 IC |
81 | } |
82 | ||
7376419a WL |
83 | static void xenvif_idx_release(struct xenvif *vif, u16 pending_idx, |
84 | u8 status); | |
85 | ||
f942dc25 IC |
86 | static void make_tx_response(struct xenvif *vif, |
87 | struct xen_netif_tx_request *txp, | |
88 | s8 st); | |
b3f980bd WL |
89 | |
90 | static inline int tx_work_todo(struct xenvif *vif); | |
91 | static inline int rx_work_todo(struct xenvif *vif); | |
92 | ||
f942dc25 IC |
93 | static struct xen_netif_rx_response *make_rx_response(struct xenvif *vif, |
94 | u16 id, | |
95 | s8 st, | |
96 | u16 offset, | |
97 | u16 size, | |
98 | u16 flags); | |
99 | ||
b3f980bd | 100 | static inline unsigned long idx_to_pfn(struct xenvif *vif, |
ea066ad1 | 101 | u16 idx) |
f942dc25 | 102 | { |
b3f980bd | 103 | return page_to_pfn(vif->mmap_pages[idx]); |
f942dc25 IC |
104 | } |
105 | ||
b3f980bd | 106 | static inline unsigned long idx_to_kaddr(struct xenvif *vif, |
ea066ad1 | 107 | u16 idx) |
f942dc25 | 108 | { |
b3f980bd | 109 | return (unsigned long)pfn_to_kaddr(idx_to_pfn(vif, idx)); |
f942dc25 IC |
110 | } |
111 | ||
f942dc25 IC |
112 | /* |
113 | * This is the amount of packet we copy rather than map, so that the | |
114 | * guest can't fiddle with the contents of the headers while we do | |
115 | * packet processing on them (netfilter, routing, etc). | |
116 | */ | |
117 | #define PKT_PROT_LEN (ETH_HLEN + \ | |
118 | VLAN_HLEN + \ | |
119 | sizeof(struct iphdr) + MAX_IPOPTLEN + \ | |
120 | sizeof(struct tcphdr) + MAX_TCP_OPTION_SPACE) | |
121 | ||
ea066ad1 IC |
122 | static u16 frag_get_pending_idx(skb_frag_t *frag) |
123 | { | |
124 | return (u16)frag->page_offset; | |
125 | } | |
126 | ||
127 | static void frag_set_pending_idx(skb_frag_t *frag, u16 pending_idx) | |
128 | { | |
129 | frag->page_offset = pending_idx; | |
130 | } | |
131 | ||
f942dc25 IC |
132 | static inline pending_ring_idx_t pending_index(unsigned i) |
133 | { | |
134 | return i & (MAX_PENDING_REQS-1); | |
135 | } | |
136 | ||
b3f980bd | 137 | static inline pending_ring_idx_t nr_pending_reqs(struct xenvif *vif) |
f942dc25 IC |
138 | { |
139 | return MAX_PENDING_REQS - | |
b3f980bd | 140 | vif->pending_prod + vif->pending_cons; |
f942dc25 IC |
141 | } |
142 | ||
143 | static int max_required_rx_slots(struct xenvif *vif) | |
144 | { | |
145 | int max = DIV_ROUND_UP(vif->dev->mtu, PAGE_SIZE); | |
146 | ||
2810e5b9 | 147 | /* XXX FIXME: RX path dependent on MAX_SKB_FRAGS */ |
f942dc25 IC |
148 | if (vif->can_sg || vif->gso || vif->gso_prefix) |
149 | max += MAX_SKB_FRAGS + 1; /* extra_info + frags */ | |
150 | ||
151 | return max; | |
152 | } | |
153 | ||
7376419a | 154 | int xenvif_rx_ring_full(struct xenvif *vif) |
f942dc25 IC |
155 | { |
156 | RING_IDX peek = vif->rx_req_cons_peek; | |
157 | RING_IDX needed = max_required_rx_slots(vif); | |
158 | ||
159 | return ((vif->rx.sring->req_prod - peek) < needed) || | |
160 | ((vif->rx.rsp_prod_pvt + XEN_NETIF_RX_RING_SIZE - peek) < needed); | |
161 | } | |
162 | ||
7376419a | 163 | int xenvif_must_stop_queue(struct xenvif *vif) |
f942dc25 | 164 | { |
7376419a | 165 | if (!xenvif_rx_ring_full(vif)) |
f942dc25 IC |
166 | return 0; |
167 | ||
168 | vif->rx.sring->req_event = vif->rx_req_cons_peek + | |
169 | max_required_rx_slots(vif); | |
170 | mb(); /* request notification /then/ check the queue */ | |
171 | ||
7376419a | 172 | return xenvif_rx_ring_full(vif); |
f942dc25 IC |
173 | } |
174 | ||
175 | /* | |
176 | * Returns true if we should start a new receive buffer instead of | |
177 | * adding 'size' bytes to a buffer which currently contains 'offset' | |
178 | * bytes. | |
179 | */ | |
180 | static bool start_new_rx_buffer(int offset, unsigned long size, int head) | |
181 | { | |
182 | /* simple case: we have completely filled the current buffer. */ | |
183 | if (offset == MAX_BUFFER_OFFSET) | |
184 | return true; | |
185 | ||
186 | /* | |
187 | * complex case: start a fresh buffer if the current frag | |
188 | * would overflow the current buffer but only if: | |
189 | * (i) this frag would fit completely in the next buffer | |
190 | * and (ii) there is already some data in the current buffer | |
191 | * and (iii) this is not the head buffer. | |
192 | * | |
193 | * Where: | |
194 | * - (i) stops us splitting a frag into two copies | |
195 | * unless the frag is too large for a single buffer. | |
196 | * - (ii) stops us from leaving a buffer pointlessly empty. | |
197 | * - (iii) stops us leaving the first buffer | |
198 | * empty. Strictly speaking this is already covered | |
199 | * by (ii) but is explicitly checked because | |
200 | * netfront relies on the first buffer being | |
201 | * non-empty and can crash otherwise. | |
202 | * | |
203 | * This means we will effectively linearise small | |
204 | * frags but do not needlessly split large buffers | |
205 | * into multiple copies tend to give large frags their | |
206 | * own buffers as before. | |
207 | */ | |
208 | if ((offset + size > MAX_BUFFER_OFFSET) && | |
209 | (size <= MAX_BUFFER_OFFSET) && offset && !head) | |
210 | return true; | |
211 | ||
212 | return false; | |
213 | } | |
214 | ||
33bc801d WL |
215 | struct xenvif_count_slot_state { |
216 | unsigned long copy_off; | |
217 | bool head; | |
218 | }; | |
219 | ||
220 | unsigned int xenvif_count_frag_slots(struct xenvif *vif, | |
221 | unsigned long offset, unsigned long size, | |
222 | struct xenvif_count_slot_state *state) | |
223 | { | |
224 | unsigned count = 0; | |
225 | ||
226 | offset &= ~PAGE_MASK; | |
227 | ||
228 | while (size > 0) { | |
229 | unsigned long bytes; | |
230 | ||
231 | bytes = PAGE_SIZE - offset; | |
232 | ||
233 | if (bytes > size) | |
234 | bytes = size; | |
235 | ||
236 | if (start_new_rx_buffer(state->copy_off, bytes, state->head)) { | |
237 | count++; | |
238 | state->copy_off = 0; | |
239 | } | |
240 | ||
241 | if (state->copy_off + bytes > MAX_BUFFER_OFFSET) | |
242 | bytes = MAX_BUFFER_OFFSET - state->copy_off; | |
243 | ||
244 | state->copy_off += bytes; | |
245 | ||
246 | offset += bytes; | |
247 | size -= bytes; | |
248 | ||
249 | if (offset == PAGE_SIZE) | |
250 | offset = 0; | |
251 | ||
252 | state->head = false; | |
253 | } | |
254 | ||
255 | return count; | |
256 | } | |
257 | ||
f942dc25 IC |
258 | /* |
259 | * Figure out how many ring slots we're going to need to send @skb to | |
260 | * the guest. This function is essentially a dry run of | |
7376419a | 261 | * xenvif_gop_frag_copy. |
f942dc25 | 262 | */ |
7376419a | 263 | unsigned int xenvif_count_skb_slots(struct xenvif *vif, struct sk_buff *skb) |
f942dc25 | 264 | { |
33bc801d | 265 | struct xenvif_count_slot_state state; |
f942dc25 | 266 | unsigned int count; |
33bc801d WL |
267 | unsigned char *data; |
268 | unsigned i; | |
f942dc25 | 269 | |
33bc801d WL |
270 | state.head = true; |
271 | state.copy_off = 0; | |
f942dc25 | 272 | |
33bc801d WL |
273 | /* Slot for the first (partial) page of data. */ |
274 | count = 1; | |
f942dc25 | 275 | |
33bc801d | 276 | /* Need a slot for the GSO prefix for GSO extra data? */ |
f942dc25 IC |
277 | if (skb_shinfo(skb)->gso_size) |
278 | count++; | |
279 | ||
33bc801d WL |
280 | data = skb->data; |
281 | while (data < skb_tail_pointer(skb)) { | |
282 | unsigned long offset = offset_in_page(data); | |
283 | unsigned long size = PAGE_SIZE - offset; | |
4f0581d2 | 284 | |
33bc801d WL |
285 | if (data + size > skb_tail_pointer(skb)) |
286 | size = skb_tail_pointer(skb) - data; | |
6a8ed462 | 287 | |
33bc801d | 288 | count += xenvif_count_frag_slots(vif, offset, size, &state); |
4f0581d2 | 289 | |
33bc801d WL |
290 | data += size; |
291 | } | |
4f0581d2 | 292 | |
33bc801d WL |
293 | for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { |
294 | unsigned long size = skb_frag_size(&skb_shinfo(skb)->frags[i]); | |
295 | unsigned long offset = skb_shinfo(skb)->frags[i].page_offset; | |
4f0581d2 | 296 | |
33bc801d | 297 | count += xenvif_count_frag_slots(vif, offset, size, &state); |
f942dc25 IC |
298 | } |
299 | return count; | |
300 | } | |
301 | ||
302 | struct netrx_pending_operations { | |
303 | unsigned copy_prod, copy_cons; | |
304 | unsigned meta_prod, meta_cons; | |
305 | struct gnttab_copy *copy; | |
b3f980bd | 306 | struct xenvif_rx_meta *meta; |
f942dc25 IC |
307 | int copy_off; |
308 | grant_ref_t copy_gref; | |
309 | }; | |
310 | ||
b3f980bd WL |
311 | static struct xenvif_rx_meta *get_next_rx_buffer(struct xenvif *vif, |
312 | struct netrx_pending_operations *npo) | |
f942dc25 | 313 | { |
b3f980bd | 314 | struct xenvif_rx_meta *meta; |
f942dc25 IC |
315 | struct xen_netif_rx_request *req; |
316 | ||
317 | req = RING_GET_REQUEST(&vif->rx, vif->rx.req_cons++); | |
318 | ||
319 | meta = npo->meta + npo->meta_prod++; | |
320 | meta->gso_size = 0; | |
321 | meta->size = 0; | |
322 | meta->id = req->id; | |
323 | ||
324 | npo->copy_off = 0; | |
325 | npo->copy_gref = req->gref; | |
326 | ||
327 | return meta; | |
328 | } | |
329 | ||
33bc801d WL |
330 | /* |
331 | * Set up the grant operations for this fragment. If it's a flipping | |
332 | * interface, we also set up the unmap request from here. | |
333 | */ | |
7376419a WL |
334 | static void xenvif_gop_frag_copy(struct xenvif *vif, struct sk_buff *skb, |
335 | struct netrx_pending_operations *npo, | |
336 | struct page *page, unsigned long size, | |
33bc801d | 337 | unsigned long offset, int *head) |
f942dc25 IC |
338 | { |
339 | struct gnttab_copy *copy_gop; | |
b3f980bd | 340 | struct xenvif_rx_meta *meta; |
f942dc25 IC |
341 | unsigned long bytes; |
342 | ||
343 | /* Data must not cross a page boundary. */ | |
6a8ed462 | 344 | BUG_ON(size + offset > PAGE_SIZE<<compound_order(page)); |
f942dc25 IC |
345 | |
346 | meta = npo->meta + npo->meta_prod - 1; | |
347 | ||
6a8ed462 IC |
348 | /* Skip unused frames from start of page */ |
349 | page += offset >> PAGE_SHIFT; | |
350 | offset &= ~PAGE_MASK; | |
351 | ||
f942dc25 | 352 | while (size > 0) { |
6a8ed462 | 353 | BUG_ON(offset >= PAGE_SIZE); |
f942dc25 IC |
354 | BUG_ON(npo->copy_off > MAX_BUFFER_OFFSET); |
355 | ||
6a8ed462 IC |
356 | bytes = PAGE_SIZE - offset; |
357 | ||
358 | if (bytes > size) | |
359 | bytes = size; | |
360 | ||
33bc801d | 361 | if (start_new_rx_buffer(npo->copy_off, bytes, *head)) { |
f942dc25 IC |
362 | /* |
363 | * Netfront requires there to be some data in the head | |
364 | * buffer. | |
365 | */ | |
33bc801d | 366 | BUG_ON(*head); |
f942dc25 IC |
367 | |
368 | meta = get_next_rx_buffer(vif, npo); | |
369 | } | |
370 | ||
f942dc25 IC |
371 | if (npo->copy_off + bytes > MAX_BUFFER_OFFSET) |
372 | bytes = MAX_BUFFER_OFFSET - npo->copy_off; | |
373 | ||
374 | copy_gop = npo->copy + npo->copy_prod++; | |
375 | copy_gop->flags = GNTCOPY_dest_gref; | |
b3f980bd WL |
376 | copy_gop->len = bytes; |
377 | ||
43e9d194 WL |
378 | copy_gop->source.domid = DOMID_SELF; |
379 | copy_gop->source.u.gmfn = virt_to_mfn(page_address(page)); | |
f942dc25 | 380 | copy_gop->source.offset = offset; |
f942dc25 | 381 | |
b3f980bd | 382 | copy_gop->dest.domid = vif->domid; |
f942dc25 IC |
383 | copy_gop->dest.offset = npo->copy_off; |
384 | copy_gop->dest.u.ref = npo->copy_gref; | |
f942dc25 IC |
385 | |
386 | npo->copy_off += bytes; | |
387 | meta->size += bytes; | |
388 | ||
389 | offset += bytes; | |
390 | size -= bytes; | |
391 | ||
6a8ed462 IC |
392 | /* Next frame */ |
393 | if (offset == PAGE_SIZE && size) { | |
394 | BUG_ON(!PageCompound(page)); | |
395 | page++; | |
396 | offset = 0; | |
397 | } | |
398 | ||
f942dc25 | 399 | /* Leave a gap for the GSO descriptor. */ |
33bc801d | 400 | if (*head && skb_shinfo(skb)->gso_size && !vif->gso_prefix) |
f942dc25 IC |
401 | vif->rx.req_cons++; |
402 | ||
33bc801d | 403 | *head = 0; /* There must be something in this buffer now. */ |
f942dc25 IC |
404 | |
405 | } | |
406 | } | |
407 | ||
408 | /* | |
409 | * Prepare an SKB to be transmitted to the frontend. | |
410 | * | |
411 | * This function is responsible for allocating grant operations, meta | |
412 | * structures, etc. | |
413 | * | |
414 | * It returns the number of meta structures consumed. The number of | |
415 | * ring slots used is always equal to the number of meta slots used | |
416 | * plus the number of GSO descriptors used. Currently, we use either | |
417 | * zero GSO descriptors (for non-GSO packets) or one descriptor (for | |
418 | * frontend-side LRO). | |
419 | */ | |
7376419a WL |
420 | static int xenvif_gop_skb(struct sk_buff *skb, |
421 | struct netrx_pending_operations *npo) | |
f942dc25 IC |
422 | { |
423 | struct xenvif *vif = netdev_priv(skb->dev); | |
424 | int nr_frags = skb_shinfo(skb)->nr_frags; | |
425 | int i; | |
426 | struct xen_netif_rx_request *req; | |
b3f980bd | 427 | struct xenvif_rx_meta *meta; |
f942dc25 | 428 | unsigned char *data; |
33bc801d | 429 | int head = 1; |
f942dc25 IC |
430 | int old_meta_prod; |
431 | ||
432 | old_meta_prod = npo->meta_prod; | |
433 | ||
434 | /* Set up a GSO prefix descriptor, if necessary */ | |
435 | if (skb_shinfo(skb)->gso_size && vif->gso_prefix) { | |
436 | req = RING_GET_REQUEST(&vif->rx, vif->rx.req_cons++); | |
437 | meta = npo->meta + npo->meta_prod++; | |
438 | meta->gso_size = skb_shinfo(skb)->gso_size; | |
439 | meta->size = 0; | |
440 | meta->id = req->id; | |
441 | } | |
442 | ||
443 | req = RING_GET_REQUEST(&vif->rx, vif->rx.req_cons++); | |
444 | meta = npo->meta + npo->meta_prod++; | |
445 | ||
446 | if (!vif->gso_prefix) | |
447 | meta->gso_size = skb_shinfo(skb)->gso_size; | |
448 | else | |
449 | meta->gso_size = 0; | |
450 | ||
451 | meta->size = 0; | |
452 | meta->id = req->id; | |
453 | npo->copy_off = 0; | |
454 | npo->copy_gref = req->gref; | |
455 | ||
456 | data = skb->data; | |
457 | while (data < skb_tail_pointer(skb)) { | |
458 | unsigned int offset = offset_in_page(data); | |
459 | unsigned int len = PAGE_SIZE - offset; | |
460 | ||
461 | if (data + len > skb_tail_pointer(skb)) | |
462 | len = skb_tail_pointer(skb) - data; | |
463 | ||
7376419a | 464 | xenvif_gop_frag_copy(vif, skb, npo, |
33bc801d | 465 | virt_to_page(data), len, offset, &head); |
f942dc25 IC |
466 | data += len; |
467 | } | |
468 | ||
469 | for (i = 0; i < nr_frags; i++) { | |
7376419a WL |
470 | xenvif_gop_frag_copy(vif, skb, npo, |
471 | skb_frag_page(&skb_shinfo(skb)->frags[i]), | |
472 | skb_frag_size(&skb_shinfo(skb)->frags[i]), | |
473 | skb_shinfo(skb)->frags[i].page_offset, | |
33bc801d | 474 | &head); |
f942dc25 IC |
475 | } |
476 | ||
477 | return npo->meta_prod - old_meta_prod; | |
478 | } | |
479 | ||
480 | /* | |
7376419a | 481 | * This is a twin to xenvif_gop_skb. Assume that xenvif_gop_skb was |
f942dc25 IC |
482 | * used to set up the operations on the top of |
483 | * netrx_pending_operations, which have since been done. Check that | |
484 | * they didn't give any errors and advance over them. | |
485 | */ | |
7376419a WL |
486 | static int xenvif_check_gop(struct xenvif *vif, int nr_meta_slots, |
487 | struct netrx_pending_operations *npo) | |
f942dc25 IC |
488 | { |
489 | struct gnttab_copy *copy_op; | |
490 | int status = XEN_NETIF_RSP_OKAY; | |
491 | int i; | |
492 | ||
493 | for (i = 0; i < nr_meta_slots; i++) { | |
494 | copy_op = npo->copy + npo->copy_cons++; | |
495 | if (copy_op->status != GNTST_okay) { | |
496 | netdev_dbg(vif->dev, | |
497 | "Bad status %d from copy to DOM%d.\n", | |
498 | copy_op->status, vif->domid); | |
499 | status = XEN_NETIF_RSP_ERROR; | |
500 | } | |
501 | } | |
502 | ||
503 | return status; | |
504 | } | |
505 | ||
7376419a WL |
506 | static void xenvif_add_frag_responses(struct xenvif *vif, int status, |
507 | struct xenvif_rx_meta *meta, | |
508 | int nr_meta_slots) | |
f942dc25 IC |
509 | { |
510 | int i; | |
511 | unsigned long offset; | |
512 | ||
513 | /* No fragments used */ | |
514 | if (nr_meta_slots <= 1) | |
515 | return; | |
516 | ||
517 | nr_meta_slots--; | |
518 | ||
519 | for (i = 0; i < nr_meta_slots; i++) { | |
520 | int flags; | |
521 | if (i == nr_meta_slots - 1) | |
522 | flags = 0; | |
523 | else | |
524 | flags = XEN_NETRXF_more_data; | |
525 | ||
526 | offset = 0; | |
527 | make_rx_response(vif, meta[i].id, status, offset, | |
528 | meta[i].size, flags); | |
529 | } | |
530 | } | |
531 | ||
33bc801d WL |
532 | struct skb_cb_overlay { |
533 | int meta_slots_used; | |
534 | }; | |
535 | ||
7376419a | 536 | static void xenvif_kick_thread(struct xenvif *vif) |
b3f980bd WL |
537 | { |
538 | wake_up(&vif->wq); | |
539 | } | |
540 | ||
7376419a | 541 | void xenvif_rx_action(struct xenvif *vif) |
f942dc25 | 542 | { |
f942dc25 | 543 | s8 status; |
e1f00a69 | 544 | u16 flags; |
f942dc25 IC |
545 | struct xen_netif_rx_response *resp; |
546 | struct sk_buff_head rxq; | |
547 | struct sk_buff *skb; | |
548 | LIST_HEAD(notify); | |
549 | int ret; | |
550 | int nr_frags; | |
551 | int count; | |
552 | unsigned long offset; | |
553 | struct skb_cb_overlay *sco; | |
b3f980bd | 554 | int need_to_notify = 0; |
f942dc25 IC |
555 | |
556 | struct netrx_pending_operations npo = { | |
b3f980bd WL |
557 | .copy = vif->grant_copy_op, |
558 | .meta = vif->meta, | |
f942dc25 IC |
559 | }; |
560 | ||
561 | skb_queue_head_init(&rxq); | |
562 | ||
563 | count = 0; | |
564 | ||
b3f980bd | 565 | while ((skb = skb_dequeue(&vif->rx_queue)) != NULL) { |
f942dc25 IC |
566 | vif = netdev_priv(skb->dev); |
567 | nr_frags = skb_shinfo(skb)->nr_frags; | |
568 | ||
569 | sco = (struct skb_cb_overlay *)skb->cb; | |
7376419a | 570 | sco->meta_slots_used = xenvif_gop_skb(skb, &npo); |
f942dc25 | 571 | |
33bc801d | 572 | count += nr_frags + 1; |
f942dc25 IC |
573 | |
574 | __skb_queue_tail(&rxq, skb); | |
575 | ||
576 | /* Filled the batch queue? */ | |
33bc801d WL |
577 | /* XXX FIXME: RX path dependent on MAX_SKB_FRAGS */ |
578 | if (count + MAX_SKB_FRAGS >= XEN_NETIF_RX_RING_SIZE) | |
f942dc25 IC |
579 | break; |
580 | } | |
581 | ||
b3f980bd | 582 | BUG_ON(npo.meta_prod > ARRAY_SIZE(vif->meta)); |
f942dc25 IC |
583 | |
584 | if (!npo.copy_prod) | |
585 | return; | |
586 | ||
b3f980bd WL |
587 | BUG_ON(npo.copy_prod > ARRAY_SIZE(vif->grant_copy_op)); |
588 | gnttab_batch_copy(vif->grant_copy_op, npo.copy_prod); | |
f942dc25 IC |
589 | |
590 | while ((skb = __skb_dequeue(&rxq)) != NULL) { | |
591 | sco = (struct skb_cb_overlay *)skb->cb; | |
592 | ||
593 | vif = netdev_priv(skb->dev); | |
594 | ||
b3f980bd | 595 | if (vif->meta[npo.meta_cons].gso_size && vif->gso_prefix) { |
f942dc25 | 596 | resp = RING_GET_RESPONSE(&vif->rx, |
b3f980bd | 597 | vif->rx.rsp_prod_pvt++); |
f942dc25 IC |
598 | |
599 | resp->flags = XEN_NETRXF_gso_prefix | XEN_NETRXF_more_data; | |
600 | ||
b3f980bd WL |
601 | resp->offset = vif->meta[npo.meta_cons].gso_size; |
602 | resp->id = vif->meta[npo.meta_cons].id; | |
f942dc25 IC |
603 | resp->status = sco->meta_slots_used; |
604 | ||
605 | npo.meta_cons++; | |
606 | sco->meta_slots_used--; | |
607 | } | |
608 | ||
609 | ||
610 | vif->dev->stats.tx_bytes += skb->len; | |
611 | vif->dev->stats.tx_packets++; | |
612 | ||
7376419a | 613 | status = xenvif_check_gop(vif, sco->meta_slots_used, &npo); |
f942dc25 IC |
614 | |
615 | if (sco->meta_slots_used == 1) | |
616 | flags = 0; | |
617 | else | |
618 | flags = XEN_NETRXF_more_data; | |
619 | ||
620 | if (skb->ip_summed == CHECKSUM_PARTIAL) /* local packet? */ | |
621 | flags |= XEN_NETRXF_csum_blank | XEN_NETRXF_data_validated; | |
622 | else if (skb->ip_summed == CHECKSUM_UNNECESSARY) | |
623 | /* remote but checksummed. */ | |
624 | flags |= XEN_NETRXF_data_validated; | |
625 | ||
626 | offset = 0; | |
b3f980bd | 627 | resp = make_rx_response(vif, vif->meta[npo.meta_cons].id, |
f942dc25 | 628 | status, offset, |
b3f980bd | 629 | vif->meta[npo.meta_cons].size, |
f942dc25 IC |
630 | flags); |
631 | ||
b3f980bd | 632 | if (vif->meta[npo.meta_cons].gso_size && !vif->gso_prefix) { |
f942dc25 IC |
633 | struct xen_netif_extra_info *gso = |
634 | (struct xen_netif_extra_info *) | |
635 | RING_GET_RESPONSE(&vif->rx, | |
636 | vif->rx.rsp_prod_pvt++); | |
637 | ||
638 | resp->flags |= XEN_NETRXF_extra_info; | |
639 | ||
b3f980bd | 640 | gso->u.gso.size = vif->meta[npo.meta_cons].gso_size; |
f942dc25 IC |
641 | gso->u.gso.type = XEN_NETIF_GSO_TYPE_TCPV4; |
642 | gso->u.gso.pad = 0; | |
643 | gso->u.gso.features = 0; | |
644 | ||
645 | gso->type = XEN_NETIF_EXTRA_TYPE_GSO; | |
646 | gso->flags = 0; | |
647 | } | |
648 | ||
7376419a WL |
649 | xenvif_add_frag_responses(vif, status, |
650 | vif->meta + npo.meta_cons + 1, | |
651 | sco->meta_slots_used); | |
f942dc25 IC |
652 | |
653 | RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&vif->rx, ret); | |
f942dc25 | 654 | |
b3f980bd WL |
655 | if (ret) |
656 | need_to_notify = 1; | |
657 | ||
f942dc25 IC |
658 | xenvif_notify_tx_completion(vif); |
659 | ||
f942dc25 IC |
660 | npo.meta_cons += sco->meta_slots_used; |
661 | dev_kfree_skb(skb); | |
662 | } | |
663 | ||
b3f980bd | 664 | if (need_to_notify) |
e1f00a69 | 665 | notify_remote_via_irq(vif->rx_irq); |
f942dc25 IC |
666 | |
667 | /* More work to do? */ | |
b3f980bd | 668 | if (!skb_queue_empty(&vif->rx_queue)) |
7376419a | 669 | xenvif_kick_thread(vif); |
f942dc25 IC |
670 | } |
671 | ||
7376419a | 672 | void xenvif_queue_tx_skb(struct xenvif *vif, struct sk_buff *skb) |
f942dc25 | 673 | { |
b3f980bd | 674 | skb_queue_tail(&vif->rx_queue, skb); |
f942dc25 | 675 | |
7376419a | 676 | xenvif_kick_thread(vif); |
f942dc25 IC |
677 | } |
678 | ||
7376419a | 679 | void xenvif_check_rx_xenvif(struct xenvif *vif) |
f942dc25 IC |
680 | { |
681 | int more_to_do; | |
682 | ||
683 | RING_FINAL_CHECK_FOR_REQUESTS(&vif->tx, more_to_do); | |
684 | ||
685 | if (more_to_do) | |
b3f980bd | 686 | napi_schedule(&vif->napi); |
f942dc25 IC |
687 | } |
688 | ||
689 | static void tx_add_credit(struct xenvif *vif) | |
690 | { | |
691 | unsigned long max_burst, max_credit; | |
692 | ||
693 | /* | |
694 | * Allow a burst big enough to transmit a jumbo packet of up to 128kB. | |
695 | * Otherwise the interface can seize up due to insufficient credit. | |
696 | */ | |
697 | max_burst = RING_GET_REQUEST(&vif->tx, vif->tx.req_cons)->size; | |
698 | max_burst = min(max_burst, 131072UL); | |
699 | max_burst = max(max_burst, vif->credit_bytes); | |
700 | ||
701 | /* Take care that adding a new chunk of credit doesn't wrap to zero. */ | |
702 | max_credit = vif->remaining_credit + vif->credit_bytes; | |
703 | if (max_credit < vif->remaining_credit) | |
704 | max_credit = ULONG_MAX; /* wrapped: clamp to ULONG_MAX */ | |
705 | ||
706 | vif->remaining_credit = min(max_credit, max_burst); | |
707 | } | |
708 | ||
709 | static void tx_credit_callback(unsigned long data) | |
710 | { | |
711 | struct xenvif *vif = (struct xenvif *)data; | |
712 | tx_add_credit(vif); | |
7376419a | 713 | xenvif_check_rx_xenvif(vif); |
f942dc25 IC |
714 | } |
715 | ||
7376419a WL |
716 | static void xenvif_tx_err(struct xenvif *vif, |
717 | struct xen_netif_tx_request *txp, RING_IDX end) | |
f942dc25 IC |
718 | { |
719 | RING_IDX cons = vif->tx.req_cons; | |
720 | ||
721 | do { | |
722 | make_tx_response(vif, txp, XEN_NETIF_RSP_ERROR); | |
b9149729 | 723 | if (cons == end) |
f942dc25 IC |
724 | break; |
725 | txp = RING_GET_REQUEST(&vif->tx, cons++); | |
726 | } while (1); | |
727 | vif->tx.req_cons = cons; | |
f942dc25 IC |
728 | } |
729 | ||
7376419a | 730 | static void xenvif_fatal_tx_err(struct xenvif *vif) |
48856286 IC |
731 | { |
732 | netdev_err(vif->dev, "fatal error; disabling device\n"); | |
733 | xenvif_carrier_off(vif); | |
48856286 IC |
734 | } |
735 | ||
7376419a WL |
736 | static int xenvif_count_requests(struct xenvif *vif, |
737 | struct xen_netif_tx_request *first, | |
738 | struct xen_netif_tx_request *txp, | |
739 | int work_to_do) | |
f942dc25 IC |
740 | { |
741 | RING_IDX cons = vif->tx.req_cons; | |
2810e5b9 WL |
742 | int slots = 0; |
743 | int drop_err = 0; | |
59ccb4eb | 744 | int more_data; |
f942dc25 IC |
745 | |
746 | if (!(first->flags & XEN_NETTXF_more_data)) | |
747 | return 0; | |
748 | ||
749 | do { | |
59ccb4eb WL |
750 | struct xen_netif_tx_request dropped_tx = { 0 }; |
751 | ||
2810e5b9 WL |
752 | if (slots >= work_to_do) { |
753 | netdev_err(vif->dev, | |
754 | "Asked for %d slots but exceeds this limit\n", | |
755 | work_to_do); | |
7376419a | 756 | xenvif_fatal_tx_err(vif); |
35876b5f | 757 | return -ENODATA; |
f942dc25 IC |
758 | } |
759 | ||
2810e5b9 WL |
760 | /* This guest is really using too many slots and |
761 | * considered malicious. | |
762 | */ | |
37641494 | 763 | if (unlikely(slots >= fatal_skb_slots)) { |
2810e5b9 WL |
764 | netdev_err(vif->dev, |
765 | "Malicious frontend using %d slots, threshold %u\n", | |
37641494 | 766 | slots, fatal_skb_slots); |
7376419a | 767 | xenvif_fatal_tx_err(vif); |
35876b5f | 768 | return -E2BIG; |
f942dc25 IC |
769 | } |
770 | ||
2810e5b9 | 771 | /* Xen network protocol had implicit dependency on |
37641494 WL |
772 | * MAX_SKB_FRAGS. XEN_NETBK_LEGACY_SLOTS_MAX is set to |
773 | * the historical MAX_SKB_FRAGS value 18 to honor the | |
774 | * same behavior as before. Any packet using more than | |
775 | * 18 slots but less than fatal_skb_slots slots is | |
776 | * dropped | |
2810e5b9 | 777 | */ |
37641494 | 778 | if (!drop_err && slots >= XEN_NETBK_LEGACY_SLOTS_MAX) { |
2810e5b9 WL |
779 | if (net_ratelimit()) |
780 | netdev_dbg(vif->dev, | |
781 | "Too many slots (%d) exceeding limit (%d), dropping packet\n", | |
37641494 | 782 | slots, XEN_NETBK_LEGACY_SLOTS_MAX); |
2810e5b9 WL |
783 | drop_err = -E2BIG; |
784 | } | |
785 | ||
59ccb4eb WL |
786 | if (drop_err) |
787 | txp = &dropped_tx; | |
788 | ||
2810e5b9 | 789 | memcpy(txp, RING_GET_REQUEST(&vif->tx, cons + slots), |
f942dc25 | 790 | sizeof(*txp)); |
03393fd5 WL |
791 | |
792 | /* If the guest submitted a frame >= 64 KiB then | |
793 | * first->size overflowed and following slots will | |
794 | * appear to be larger than the frame. | |
795 | * | |
796 | * This cannot be fatal error as there are buggy | |
797 | * frontends that do this. | |
798 | * | |
799 | * Consume all slots and drop the packet. | |
800 | */ | |
801 | if (!drop_err && txp->size > first->size) { | |
802 | if (net_ratelimit()) | |
803 | netdev_dbg(vif->dev, | |
804 | "Invalid tx request, slot size %u > remaining size %u\n", | |
805 | txp->size, first->size); | |
806 | drop_err = -EIO; | |
f942dc25 IC |
807 | } |
808 | ||
809 | first->size -= txp->size; | |
2810e5b9 | 810 | slots++; |
f942dc25 IC |
811 | |
812 | if (unlikely((txp->offset + txp->size) > PAGE_SIZE)) { | |
2810e5b9 | 813 | netdev_err(vif->dev, "Cross page boundary, txp->offset: %x, size: %u\n", |
f942dc25 | 814 | txp->offset, txp->size); |
7376419a | 815 | xenvif_fatal_tx_err(vif); |
35876b5f | 816 | return -EINVAL; |
f942dc25 | 817 | } |
59ccb4eb WL |
818 | |
819 | more_data = txp->flags & XEN_NETTXF_more_data; | |
820 | ||
821 | if (!drop_err) | |
822 | txp++; | |
823 | ||
824 | } while (more_data); | |
2810e5b9 WL |
825 | |
826 | if (drop_err) { | |
7376419a | 827 | xenvif_tx_err(vif, first, cons + slots); |
2810e5b9 WL |
828 | return drop_err; |
829 | } | |
830 | ||
831 | return slots; | |
f942dc25 IC |
832 | } |
833 | ||
7376419a WL |
834 | static struct page *xenvif_alloc_page(struct xenvif *vif, |
835 | u16 pending_idx) | |
f942dc25 IC |
836 | { |
837 | struct page *page; | |
b3f980bd WL |
838 | |
839 | page = alloc_page(GFP_ATOMIC|__GFP_COLD); | |
f942dc25 IC |
840 | if (!page) |
841 | return NULL; | |
b3f980bd WL |
842 | vif->mmap_pages[pending_idx] = page; |
843 | ||
f942dc25 IC |
844 | return page; |
845 | } | |
846 | ||
7376419a WL |
847 | static struct gnttab_copy *xenvif_get_requests(struct xenvif *vif, |
848 | struct sk_buff *skb, | |
849 | struct xen_netif_tx_request *txp, | |
850 | struct gnttab_copy *gop) | |
f942dc25 IC |
851 | { |
852 | struct skb_shared_info *shinfo = skb_shinfo(skb); | |
853 | skb_frag_t *frags = shinfo->frags; | |
ea066ad1 | 854 | u16 pending_idx = *((u16 *)skb->data); |
2810e5b9 WL |
855 | u16 head_idx = 0; |
856 | int slot, start; | |
857 | struct page *page; | |
858 | pending_ring_idx_t index, start_idx = 0; | |
859 | uint16_t dst_offset; | |
860 | unsigned int nr_slots; | |
861 | struct pending_tx_info *first = NULL; | |
862 | ||
863 | /* At this point shinfo->nr_frags is in fact the number of | |
37641494 | 864 | * slots, which can be as large as XEN_NETBK_LEGACY_SLOTS_MAX. |
2810e5b9 WL |
865 | */ |
866 | nr_slots = shinfo->nr_frags; | |
f942dc25 IC |
867 | |
868 | /* Skip first skb fragment if it is on same page as header fragment. */ | |
ea066ad1 | 869 | start = (frag_get_pending_idx(&shinfo->frags[0]) == pending_idx); |
f942dc25 | 870 | |
2810e5b9 WL |
871 | /* Coalesce tx requests, at this point the packet passed in |
872 | * should be <= 64K. Any packets larger than 64K have been | |
7376419a | 873 | * handled in xenvif_count_requests(). |
2810e5b9 WL |
874 | */ |
875 | for (shinfo->nr_frags = slot = start; slot < nr_slots; | |
876 | shinfo->nr_frags++) { | |
f942dc25 | 877 | struct pending_tx_info *pending_tx_info = |
b3f980bd | 878 | vif->pending_tx_info; |
f942dc25 | 879 | |
b3f980bd | 880 | page = alloc_page(GFP_ATOMIC|__GFP_COLD); |
f942dc25 | 881 | if (!page) |
4cc7c1cb | 882 | goto err; |
f942dc25 | 883 | |
2810e5b9 WL |
884 | dst_offset = 0; |
885 | first = NULL; | |
886 | while (dst_offset < PAGE_SIZE && slot < nr_slots) { | |
887 | gop->flags = GNTCOPY_source_gref; | |
888 | ||
889 | gop->source.u.ref = txp->gref; | |
890 | gop->source.domid = vif->domid; | |
891 | gop->source.offset = txp->offset; | |
892 | ||
893 | gop->dest.domid = DOMID_SELF; | |
894 | ||
895 | gop->dest.offset = dst_offset; | |
896 | gop->dest.u.gmfn = virt_to_mfn(page_address(page)); | |
897 | ||
898 | if (dst_offset + txp->size > PAGE_SIZE) { | |
899 | /* This page can only merge a portion | |
900 | * of tx request. Do not increment any | |
901 | * pointer / counter here. The txp | |
902 | * will be dealt with in future | |
903 | * rounds, eventually hitting the | |
904 | * `else` branch. | |
905 | */ | |
906 | gop->len = PAGE_SIZE - dst_offset; | |
907 | txp->offset += gop->len; | |
908 | txp->size -= gop->len; | |
909 | dst_offset += gop->len; /* quit loop */ | |
910 | } else { | |
911 | /* This tx request can be merged in the page */ | |
912 | gop->len = txp->size; | |
913 | dst_offset += gop->len; | |
914 | ||
b3f980bd | 915 | index = pending_index(vif->pending_cons++); |
2810e5b9 | 916 | |
b3f980bd | 917 | pending_idx = vif->pending_ring[index]; |
2810e5b9 WL |
918 | |
919 | memcpy(&pending_tx_info[pending_idx].req, txp, | |
920 | sizeof(*txp)); | |
2810e5b9 WL |
921 | |
922 | /* Poison these fields, corresponding | |
923 | * fields for head tx req will be set | |
924 | * to correct values after the loop. | |
925 | */ | |
b3f980bd | 926 | vif->mmap_pages[pending_idx] = (void *)(~0UL); |
2810e5b9 WL |
927 | pending_tx_info[pending_idx].head = |
928 | INVALID_PENDING_RING_IDX; | |
929 | ||
930 | if (!first) { | |
931 | first = &pending_tx_info[pending_idx]; | |
932 | start_idx = index; | |
933 | head_idx = pending_idx; | |
934 | } | |
935 | ||
936 | txp++; | |
937 | slot++; | |
938 | } | |
f942dc25 | 939 | |
2810e5b9 WL |
940 | gop++; |
941 | } | |
f942dc25 | 942 | |
2810e5b9 WL |
943 | first->req.offset = 0; |
944 | first->req.size = dst_offset; | |
945 | first->head = start_idx; | |
b3f980bd | 946 | vif->mmap_pages[head_idx] = page; |
2810e5b9 | 947 | frag_set_pending_idx(&frags[shinfo->nr_frags], head_idx); |
f942dc25 IC |
948 | } |
949 | ||
2810e5b9 WL |
950 | BUG_ON(shinfo->nr_frags > MAX_SKB_FRAGS); |
951 | ||
f942dc25 | 952 | return gop; |
4cc7c1cb IC |
953 | err: |
954 | /* Unwind, freeing all pages and sending error responses. */ | |
2810e5b9 | 955 | while (shinfo->nr_frags-- > start) { |
7376419a | 956 | xenvif_idx_release(vif, |
2810e5b9 WL |
957 | frag_get_pending_idx(&frags[shinfo->nr_frags]), |
958 | XEN_NETIF_RSP_ERROR); | |
4cc7c1cb IC |
959 | } |
960 | /* The head too, if necessary. */ | |
961 | if (start) | |
7376419a | 962 | xenvif_idx_release(vif, pending_idx, XEN_NETIF_RSP_ERROR); |
4cc7c1cb IC |
963 | |
964 | return NULL; | |
f942dc25 IC |
965 | } |
966 | ||
7376419a WL |
967 | static int xenvif_tx_check_gop(struct xenvif *vif, |
968 | struct sk_buff *skb, | |
969 | struct gnttab_copy **gopp) | |
f942dc25 IC |
970 | { |
971 | struct gnttab_copy *gop = *gopp; | |
ea066ad1 | 972 | u16 pending_idx = *((u16 *)skb->data); |
f942dc25 | 973 | struct skb_shared_info *shinfo = skb_shinfo(skb); |
2810e5b9 | 974 | struct pending_tx_info *tx_info; |
f942dc25 IC |
975 | int nr_frags = shinfo->nr_frags; |
976 | int i, err, start; | |
2810e5b9 | 977 | u16 peek; /* peek into next tx request */ |
f942dc25 IC |
978 | |
979 | /* Check status of header. */ | |
980 | err = gop->status; | |
7d5145d8 | 981 | if (unlikely(err)) |
7376419a | 982 | xenvif_idx_release(vif, pending_idx, XEN_NETIF_RSP_ERROR); |
f942dc25 IC |
983 | |
984 | /* Skip first skb fragment if it is on same page as header fragment. */ | |
ea066ad1 | 985 | start = (frag_get_pending_idx(&shinfo->frags[0]) == pending_idx); |
f942dc25 IC |
986 | |
987 | for (i = start; i < nr_frags; i++) { | |
988 | int j, newerr; | |
2810e5b9 | 989 | pending_ring_idx_t head; |
f942dc25 | 990 | |
ea066ad1 | 991 | pending_idx = frag_get_pending_idx(&shinfo->frags[i]); |
b3f980bd | 992 | tx_info = &vif->pending_tx_info[pending_idx]; |
2810e5b9 | 993 | head = tx_info->head; |
f942dc25 IC |
994 | |
995 | /* Check error status: if okay then remember grant handle. */ | |
2810e5b9 WL |
996 | do { |
997 | newerr = (++gop)->status; | |
998 | if (newerr) | |
999 | break; | |
b3f980bd WL |
1000 | peek = vif->pending_ring[pending_index(++head)]; |
1001 | } while (!pending_tx_is_head(vif, peek)); | |
2810e5b9 | 1002 | |
f942dc25 IC |
1003 | if (likely(!newerr)) { |
1004 | /* Had a previous error? Invalidate this fragment. */ | |
1005 | if (unlikely(err)) | |
7376419a WL |
1006 | xenvif_idx_release(vif, pending_idx, |
1007 | XEN_NETIF_RSP_OKAY); | |
f942dc25 IC |
1008 | continue; |
1009 | } | |
1010 | ||
1011 | /* Error on this fragment: respond to client with an error. */ | |
7376419a | 1012 | xenvif_idx_release(vif, pending_idx, XEN_NETIF_RSP_ERROR); |
f942dc25 IC |
1013 | |
1014 | /* Not the first error? Preceding frags already invalidated. */ | |
1015 | if (err) | |
1016 | continue; | |
1017 | ||
1018 | /* First error: invalidate header and preceding fragments. */ | |
1019 | pending_idx = *((u16 *)skb->data); | |
7376419a | 1020 | xenvif_idx_release(vif, pending_idx, XEN_NETIF_RSP_OKAY); |
f942dc25 | 1021 | for (j = start; j < i; j++) { |
5ccb3ea7 | 1022 | pending_idx = frag_get_pending_idx(&shinfo->frags[j]); |
7376419a WL |
1023 | xenvif_idx_release(vif, pending_idx, |
1024 | XEN_NETIF_RSP_OKAY); | |
f942dc25 IC |
1025 | } |
1026 | ||
1027 | /* Remember the error: invalidate all subsequent fragments. */ | |
1028 | err = newerr; | |
1029 | } | |
1030 | ||
1031 | *gopp = gop + 1; | |
1032 | return err; | |
1033 | } | |
1034 | ||
7376419a | 1035 | static void xenvif_fill_frags(struct xenvif *vif, struct sk_buff *skb) |
f942dc25 IC |
1036 | { |
1037 | struct skb_shared_info *shinfo = skb_shinfo(skb); | |
1038 | int nr_frags = shinfo->nr_frags; | |
1039 | int i; | |
1040 | ||
1041 | for (i = 0; i < nr_frags; i++) { | |
1042 | skb_frag_t *frag = shinfo->frags + i; | |
1043 | struct xen_netif_tx_request *txp; | |
ea066ad1 IC |
1044 | struct page *page; |
1045 | u16 pending_idx; | |
f942dc25 | 1046 | |
ea066ad1 | 1047 | pending_idx = frag_get_pending_idx(frag); |
f942dc25 | 1048 | |
b3f980bd WL |
1049 | txp = &vif->pending_tx_info[pending_idx].req; |
1050 | page = virt_to_page(idx_to_kaddr(vif, pending_idx)); | |
ea066ad1 | 1051 | __skb_fill_page_desc(skb, i, page, txp->offset, txp->size); |
f942dc25 IC |
1052 | skb->len += txp->size; |
1053 | skb->data_len += txp->size; | |
1054 | skb->truesize += txp->size; | |
1055 | ||
7376419a | 1056 | /* Take an extra reference to offset xenvif_idx_release */ |
b3f980bd | 1057 | get_page(vif->mmap_pages[pending_idx]); |
7376419a | 1058 | xenvif_idx_release(vif, pending_idx, XEN_NETIF_RSP_OKAY); |
f942dc25 IC |
1059 | } |
1060 | } | |
1061 | ||
7376419a | 1062 | static int xenvif_get_extras(struct xenvif *vif, |
f942dc25 IC |
1063 | struct xen_netif_extra_info *extras, |
1064 | int work_to_do) | |
1065 | { | |
1066 | struct xen_netif_extra_info extra; | |
1067 | RING_IDX cons = vif->tx.req_cons; | |
1068 | ||
1069 | do { | |
1070 | if (unlikely(work_to_do-- <= 0)) { | |
48856286 | 1071 | netdev_err(vif->dev, "Missing extra info\n"); |
7376419a | 1072 | xenvif_fatal_tx_err(vif); |
f942dc25 IC |
1073 | return -EBADR; |
1074 | } | |
1075 | ||
1076 | memcpy(&extra, RING_GET_REQUEST(&vif->tx, cons), | |
1077 | sizeof(extra)); | |
1078 | if (unlikely(!extra.type || | |
1079 | extra.type >= XEN_NETIF_EXTRA_TYPE_MAX)) { | |
1080 | vif->tx.req_cons = ++cons; | |
48856286 | 1081 | netdev_err(vif->dev, |
f942dc25 | 1082 | "Invalid extra type: %d\n", extra.type); |
7376419a | 1083 | xenvif_fatal_tx_err(vif); |
f942dc25 IC |
1084 | return -EINVAL; |
1085 | } | |
1086 | ||
1087 | memcpy(&extras[extra.type - 1], &extra, sizeof(extra)); | |
1088 | vif->tx.req_cons = ++cons; | |
1089 | } while (extra.flags & XEN_NETIF_EXTRA_FLAG_MORE); | |
1090 | ||
1091 | return work_to_do; | |
1092 | } | |
1093 | ||
7376419a WL |
1094 | static int xenvif_set_skb_gso(struct xenvif *vif, |
1095 | struct sk_buff *skb, | |
1096 | struct xen_netif_extra_info *gso) | |
f942dc25 IC |
1097 | { |
1098 | if (!gso->u.gso.size) { | |
48856286 | 1099 | netdev_err(vif->dev, "GSO size must not be zero.\n"); |
7376419a | 1100 | xenvif_fatal_tx_err(vif); |
f942dc25 IC |
1101 | return -EINVAL; |
1102 | } | |
1103 | ||
1104 | /* Currently only TCPv4 S.O. is supported. */ | |
1105 | if (gso->u.gso.type != XEN_NETIF_GSO_TYPE_TCPV4) { | |
48856286 | 1106 | netdev_err(vif->dev, "Bad GSO type %d.\n", gso->u.gso.type); |
7376419a | 1107 | xenvif_fatal_tx_err(vif); |
f942dc25 IC |
1108 | return -EINVAL; |
1109 | } | |
1110 | ||
1111 | skb_shinfo(skb)->gso_size = gso->u.gso.size; | |
1112 | skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4; | |
1113 | ||
1114 | /* Header must be checked, and gso_segs computed. */ | |
1115 | skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; | |
1116 | skb_shinfo(skb)->gso_segs = 0; | |
1117 | ||
1118 | return 0; | |
1119 | } | |
1120 | ||
1121 | static int checksum_setup(struct xenvif *vif, struct sk_buff *skb) | |
1122 | { | |
1123 | struct iphdr *iph; | |
f942dc25 IC |
1124 | int err = -EPROTO; |
1125 | int recalculate_partial_csum = 0; | |
1126 | ||
1127 | /* | |
1128 | * A GSO SKB must be CHECKSUM_PARTIAL. However some buggy | |
1129 | * peers can fail to set NETRXF_csum_blank when sending a GSO | |
1130 | * frame. In this case force the SKB to CHECKSUM_PARTIAL and | |
1131 | * recalculate the partial checksum. | |
1132 | */ | |
1133 | if (skb->ip_summed != CHECKSUM_PARTIAL && skb_is_gso(skb)) { | |
1134 | vif->rx_gso_checksum_fixup++; | |
1135 | skb->ip_summed = CHECKSUM_PARTIAL; | |
1136 | recalculate_partial_csum = 1; | |
1137 | } | |
1138 | ||
1139 | /* A non-CHECKSUM_PARTIAL SKB does not require setup. */ | |
1140 | if (skb->ip_summed != CHECKSUM_PARTIAL) | |
1141 | return 0; | |
1142 | ||
1143 | if (skb->protocol != htons(ETH_P_IP)) | |
1144 | goto out; | |
1145 | ||
1146 | iph = (void *)skb->data; | |
f942dc25 IC |
1147 | switch (iph->protocol) { |
1148 | case IPPROTO_TCP: | |
bea89336 JW |
1149 | if (!skb_partial_csum_set(skb, 4 * iph->ihl, |
1150 | offsetof(struct tcphdr, check))) | |
1151 | goto out; | |
f942dc25 IC |
1152 | |
1153 | if (recalculate_partial_csum) { | |
bea89336 | 1154 | struct tcphdr *tcph = tcp_hdr(skb); |
f942dc25 IC |
1155 | tcph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, |
1156 | skb->len - iph->ihl*4, | |
1157 | IPPROTO_TCP, 0); | |
1158 | } | |
1159 | break; | |
1160 | case IPPROTO_UDP: | |
bea89336 JW |
1161 | if (!skb_partial_csum_set(skb, 4 * iph->ihl, |
1162 | offsetof(struct udphdr, check))) | |
1163 | goto out; | |
f942dc25 IC |
1164 | |
1165 | if (recalculate_partial_csum) { | |
bea89336 | 1166 | struct udphdr *udph = udp_hdr(skb); |
f942dc25 IC |
1167 | udph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, |
1168 | skb->len - iph->ihl*4, | |
1169 | IPPROTO_UDP, 0); | |
1170 | } | |
1171 | break; | |
1172 | default: | |
1173 | if (net_ratelimit()) | |
1174 | netdev_err(vif->dev, | |
1175 | "Attempting to checksum a non-TCP/UDP packet, dropping a protocol %d packet\n", | |
1176 | iph->protocol); | |
1177 | goto out; | |
1178 | } | |
1179 | ||
f942dc25 IC |
1180 | err = 0; |
1181 | ||
1182 | out: | |
1183 | return err; | |
1184 | } | |
1185 | ||
1186 | static bool tx_credit_exceeded(struct xenvif *vif, unsigned size) | |
1187 | { | |
1188 | unsigned long now = jiffies; | |
1189 | unsigned long next_credit = | |
1190 | vif->credit_timeout.expires + | |
1191 | msecs_to_jiffies(vif->credit_usec / 1000); | |
1192 | ||
1193 | /* Timer could already be pending in rare cases. */ | |
1194 | if (timer_pending(&vif->credit_timeout)) | |
1195 | return true; | |
1196 | ||
1197 | /* Passed the point where we can replenish credit? */ | |
1198 | if (time_after_eq(now, next_credit)) { | |
1199 | vif->credit_timeout.expires = now; | |
1200 | tx_add_credit(vif); | |
1201 | } | |
1202 | ||
1203 | /* Still too big to send right now? Set a callback. */ | |
1204 | if (size > vif->remaining_credit) { | |
1205 | vif->credit_timeout.data = | |
1206 | (unsigned long)vif; | |
1207 | vif->credit_timeout.function = | |
1208 | tx_credit_callback; | |
1209 | mod_timer(&vif->credit_timeout, | |
1210 | next_credit); | |
1211 | ||
1212 | return true; | |
1213 | } | |
1214 | ||
1215 | return false; | |
1216 | } | |
1217 | ||
7376419a | 1218 | static unsigned xenvif_tx_build_gops(struct xenvif *vif) |
f942dc25 | 1219 | { |
b3f980bd | 1220 | struct gnttab_copy *gop = vif->tx_copy_ops, *request_gop; |
f942dc25 IC |
1221 | struct sk_buff *skb; |
1222 | int ret; | |
1223 | ||
b3f980bd WL |
1224 | while ((nr_pending_reqs(vif) + XEN_NETBK_LEGACY_SLOTS_MAX |
1225 | < MAX_PENDING_REQS)) { | |
f942dc25 | 1226 | struct xen_netif_tx_request txreq; |
37641494 | 1227 | struct xen_netif_tx_request txfrags[XEN_NETBK_LEGACY_SLOTS_MAX]; |
f942dc25 IC |
1228 | struct page *page; |
1229 | struct xen_netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX-1]; | |
1230 | u16 pending_idx; | |
1231 | RING_IDX idx; | |
1232 | int work_to_do; | |
1233 | unsigned int data_len; | |
1234 | pending_ring_idx_t index; | |
1235 | ||
48856286 IC |
1236 | if (vif->tx.sring->req_prod - vif->tx.req_cons > |
1237 | XEN_NETIF_TX_RING_SIZE) { | |
1238 | netdev_err(vif->dev, | |
1239 | "Impossible number of requests. " | |
1240 | "req_prod %d, req_cons %d, size %ld\n", | |
1241 | vif->tx.sring->req_prod, vif->tx.req_cons, | |
1242 | XEN_NETIF_TX_RING_SIZE); | |
7376419a | 1243 | xenvif_fatal_tx_err(vif); |
48856286 IC |
1244 | continue; |
1245 | } | |
1246 | ||
f942dc25 | 1247 | RING_FINAL_CHECK_FOR_REQUESTS(&vif->tx, work_to_do); |
b3f980bd WL |
1248 | if (!work_to_do) |
1249 | break; | |
f942dc25 IC |
1250 | |
1251 | idx = vif->tx.req_cons; | |
1252 | rmb(); /* Ensure that we see the request before we copy it. */ | |
1253 | memcpy(&txreq, RING_GET_REQUEST(&vif->tx, idx), sizeof(txreq)); | |
1254 | ||
1255 | /* Credit-based scheduling. */ | |
1256 | if (txreq.size > vif->remaining_credit && | |
b3f980bd WL |
1257 | tx_credit_exceeded(vif, txreq.size)) |
1258 | break; | |
f942dc25 IC |
1259 | |
1260 | vif->remaining_credit -= txreq.size; | |
1261 | ||
1262 | work_to_do--; | |
1263 | vif->tx.req_cons = ++idx; | |
1264 | ||
1265 | memset(extras, 0, sizeof(extras)); | |
1266 | if (txreq.flags & XEN_NETTXF_extra_info) { | |
7376419a WL |
1267 | work_to_do = xenvif_get_extras(vif, extras, |
1268 | work_to_do); | |
f942dc25 | 1269 | idx = vif->tx.req_cons; |
48856286 | 1270 | if (unlikely(work_to_do < 0)) |
b3f980bd | 1271 | break; |
f942dc25 IC |
1272 | } |
1273 | ||
7376419a | 1274 | ret = xenvif_count_requests(vif, &txreq, txfrags, work_to_do); |
48856286 | 1275 | if (unlikely(ret < 0)) |
b3f980bd | 1276 | break; |
48856286 | 1277 | |
f942dc25 IC |
1278 | idx += ret; |
1279 | ||
1280 | if (unlikely(txreq.size < ETH_HLEN)) { | |
1281 | netdev_dbg(vif->dev, | |
1282 | "Bad packet size: %d\n", txreq.size); | |
7376419a | 1283 | xenvif_tx_err(vif, &txreq, idx); |
b3f980bd | 1284 | break; |
f942dc25 IC |
1285 | } |
1286 | ||
1287 | /* No crossing a page as the payload mustn't fragment. */ | |
1288 | if (unlikely((txreq.offset + txreq.size) > PAGE_SIZE)) { | |
48856286 | 1289 | netdev_err(vif->dev, |
f942dc25 IC |
1290 | "txreq.offset: %x, size: %u, end: %lu\n", |
1291 | txreq.offset, txreq.size, | |
1292 | (txreq.offset&~PAGE_MASK) + txreq.size); | |
7376419a | 1293 | xenvif_fatal_tx_err(vif); |
b3f980bd | 1294 | break; |
f942dc25 IC |
1295 | } |
1296 | ||
b3f980bd WL |
1297 | index = pending_index(vif->pending_cons); |
1298 | pending_idx = vif->pending_ring[index]; | |
f942dc25 IC |
1299 | |
1300 | data_len = (txreq.size > PKT_PROT_LEN && | |
37641494 | 1301 | ret < XEN_NETBK_LEGACY_SLOTS_MAX) ? |
f942dc25 IC |
1302 | PKT_PROT_LEN : txreq.size; |
1303 | ||
1304 | skb = alloc_skb(data_len + NET_SKB_PAD + NET_IP_ALIGN, | |
1305 | GFP_ATOMIC | __GFP_NOWARN); | |
1306 | if (unlikely(skb == NULL)) { | |
1307 | netdev_dbg(vif->dev, | |
1308 | "Can't allocate a skb in start_xmit.\n"); | |
7376419a | 1309 | xenvif_tx_err(vif, &txreq, idx); |
f942dc25 IC |
1310 | break; |
1311 | } | |
1312 | ||
1313 | /* Packets passed to netif_rx() must have some headroom. */ | |
1314 | skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN); | |
1315 | ||
1316 | if (extras[XEN_NETIF_EXTRA_TYPE_GSO - 1].type) { | |
1317 | struct xen_netif_extra_info *gso; | |
1318 | gso = &extras[XEN_NETIF_EXTRA_TYPE_GSO - 1]; | |
1319 | ||
7376419a WL |
1320 | if (xenvif_set_skb_gso(vif, skb, gso)) { |
1321 | /* Failure in xenvif_set_skb_gso is fatal. */ | |
f942dc25 | 1322 | kfree_skb(skb); |
b3f980bd | 1323 | break; |
f942dc25 IC |
1324 | } |
1325 | } | |
1326 | ||
1327 | /* XXX could copy straight to head */ | |
7376419a | 1328 | page = xenvif_alloc_page(vif, pending_idx); |
f942dc25 IC |
1329 | if (!page) { |
1330 | kfree_skb(skb); | |
7376419a | 1331 | xenvif_tx_err(vif, &txreq, idx); |
b3f980bd | 1332 | break; |
f942dc25 IC |
1333 | } |
1334 | ||
f942dc25 IC |
1335 | gop->source.u.ref = txreq.gref; |
1336 | gop->source.domid = vif->domid; | |
1337 | gop->source.offset = txreq.offset; | |
1338 | ||
1339 | gop->dest.u.gmfn = virt_to_mfn(page_address(page)); | |
1340 | gop->dest.domid = DOMID_SELF; | |
1341 | gop->dest.offset = txreq.offset; | |
1342 | ||
1343 | gop->len = txreq.size; | |
1344 | gop->flags = GNTCOPY_source_gref; | |
1345 | ||
1346 | gop++; | |
1347 | ||
b3f980bd | 1348 | memcpy(&vif->pending_tx_info[pending_idx].req, |
f942dc25 | 1349 | &txreq, sizeof(txreq)); |
b3f980bd | 1350 | vif->pending_tx_info[pending_idx].head = index; |
f942dc25 IC |
1351 | *((u16 *)skb->data) = pending_idx; |
1352 | ||
1353 | __skb_put(skb, data_len); | |
1354 | ||
1355 | skb_shinfo(skb)->nr_frags = ret; | |
1356 | if (data_len < txreq.size) { | |
1357 | skb_shinfo(skb)->nr_frags++; | |
ea066ad1 IC |
1358 | frag_set_pending_idx(&skb_shinfo(skb)->frags[0], |
1359 | pending_idx); | |
f942dc25 | 1360 | } else { |
ea066ad1 IC |
1361 | frag_set_pending_idx(&skb_shinfo(skb)->frags[0], |
1362 | INVALID_PENDING_IDX); | |
f942dc25 IC |
1363 | } |
1364 | ||
b3f980bd | 1365 | vif->pending_cons++; |
f942dc25 | 1366 | |
7376419a | 1367 | request_gop = xenvif_get_requests(vif, skb, txfrags, gop); |
f942dc25 IC |
1368 | if (request_gop == NULL) { |
1369 | kfree_skb(skb); | |
7376419a | 1370 | xenvif_tx_err(vif, &txreq, idx); |
b3f980bd | 1371 | break; |
f942dc25 IC |
1372 | } |
1373 | gop = request_gop; | |
1374 | ||
b3f980bd | 1375 | __skb_queue_tail(&vif->tx_queue, skb); |
1e0b6eac | 1376 | |
f942dc25 | 1377 | vif->tx.req_cons = idx; |
f942dc25 | 1378 | |
b3f980bd | 1379 | if ((gop-vif->tx_copy_ops) >= ARRAY_SIZE(vif->tx_copy_ops)) |
f942dc25 IC |
1380 | break; |
1381 | } | |
1382 | ||
b3f980bd | 1383 | return gop - vif->tx_copy_ops; |
f942dc25 IC |
1384 | } |
1385 | ||
b3f980bd | 1386 | |
7376419a | 1387 | static int xenvif_tx_submit(struct xenvif *vif, int budget) |
f942dc25 | 1388 | { |
b3f980bd | 1389 | struct gnttab_copy *gop = vif->tx_copy_ops; |
f942dc25 | 1390 | struct sk_buff *skb; |
b3f980bd | 1391 | int work_done = 0; |
f942dc25 | 1392 | |
b3f980bd WL |
1393 | while (work_done < budget && |
1394 | (skb = __skb_dequeue(&vif->tx_queue)) != NULL) { | |
f942dc25 | 1395 | struct xen_netif_tx_request *txp; |
f942dc25 IC |
1396 | u16 pending_idx; |
1397 | unsigned data_len; | |
1398 | ||
1399 | pending_idx = *((u16 *)skb->data); | |
b3f980bd | 1400 | txp = &vif->pending_tx_info[pending_idx].req; |
f942dc25 IC |
1401 | |
1402 | /* Check the remap error code. */ | |
7376419a | 1403 | if (unlikely(xenvif_tx_check_gop(vif, skb, &gop))) { |
f942dc25 IC |
1404 | netdev_dbg(vif->dev, "netback grant failed.\n"); |
1405 | skb_shinfo(skb)->nr_frags = 0; | |
1406 | kfree_skb(skb); | |
1407 | continue; | |
1408 | } | |
1409 | ||
1410 | data_len = skb->len; | |
1411 | memcpy(skb->data, | |
b3f980bd | 1412 | (void *)(idx_to_kaddr(vif, pending_idx)|txp->offset), |
f942dc25 IC |
1413 | data_len); |
1414 | if (data_len < txp->size) { | |
1415 | /* Append the packet payload as a fragment. */ | |
1416 | txp->offset += data_len; | |
1417 | txp->size -= data_len; | |
1418 | } else { | |
1419 | /* Schedule a response immediately. */ | |
7376419a WL |
1420 | xenvif_idx_release(vif, pending_idx, |
1421 | XEN_NETIF_RSP_OKAY); | |
f942dc25 IC |
1422 | } |
1423 | ||
1424 | if (txp->flags & XEN_NETTXF_csum_blank) | |
1425 | skb->ip_summed = CHECKSUM_PARTIAL; | |
1426 | else if (txp->flags & XEN_NETTXF_data_validated) | |
1427 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
1428 | ||
7376419a | 1429 | xenvif_fill_frags(vif, skb); |
f942dc25 IC |
1430 | |
1431 | /* | |
1432 | * If the initial fragment was < PKT_PROT_LEN then | |
1433 | * pull through some bytes from the other fragments to | |
1434 | * increase the linear region to PKT_PROT_LEN bytes. | |
1435 | */ | |
1436 | if (skb_headlen(skb) < PKT_PROT_LEN && skb_is_nonlinear(skb)) { | |
1437 | int target = min_t(int, skb->len, PKT_PROT_LEN); | |
1438 | __pskb_pull_tail(skb, target - skb_headlen(skb)); | |
1439 | } | |
1440 | ||
1441 | skb->dev = vif->dev; | |
1442 | skb->protocol = eth_type_trans(skb, skb->dev); | |
f9ca8f74 | 1443 | skb_reset_network_header(skb); |
f942dc25 IC |
1444 | |
1445 | if (checksum_setup(vif, skb)) { | |
1446 | netdev_dbg(vif->dev, | |
1447 | "Can't setup checksum in net_tx_action\n"); | |
1448 | kfree_skb(skb); | |
1449 | continue; | |
1450 | } | |
1451 | ||
40893fd0 | 1452 | skb_probe_transport_header(skb, 0); |
f9ca8f74 | 1453 | |
f942dc25 IC |
1454 | vif->dev->stats.rx_bytes += skb->len; |
1455 | vif->dev->stats.rx_packets++; | |
1456 | ||
b3f980bd WL |
1457 | work_done++; |
1458 | ||
1459 | netif_receive_skb(skb); | |
f942dc25 | 1460 | } |
b3f980bd WL |
1461 | |
1462 | return work_done; | |
f942dc25 IC |
1463 | } |
1464 | ||
1465 | /* Called after netfront has transmitted */ | |
7376419a | 1466 | int xenvif_tx_action(struct xenvif *vif, int budget) |
f942dc25 IC |
1467 | { |
1468 | unsigned nr_gops; | |
b3f980bd | 1469 | int work_done; |
f942dc25 | 1470 | |
b3f980bd WL |
1471 | if (unlikely(!tx_work_todo(vif))) |
1472 | return 0; | |
1473 | ||
7376419a | 1474 | nr_gops = xenvif_tx_build_gops(vif); |
f942dc25 IC |
1475 | |
1476 | if (nr_gops == 0) | |
b3f980bd WL |
1477 | return 0; |
1478 | ||
1479 | gnttab_batch_copy(vif->tx_copy_ops, nr_gops); | |
f942dc25 | 1480 | |
7376419a | 1481 | work_done = xenvif_tx_submit(vif, nr_gops); |
f942dc25 | 1482 | |
b3f980bd | 1483 | return work_done; |
f942dc25 IC |
1484 | } |
1485 | ||
7376419a WL |
1486 | static void xenvif_idx_release(struct xenvif *vif, u16 pending_idx, |
1487 | u8 status) | |
f942dc25 | 1488 | { |
f942dc25 | 1489 | struct pending_tx_info *pending_tx_info; |
2810e5b9 WL |
1490 | pending_ring_idx_t head; |
1491 | u16 peek; /* peek into next tx request */ | |
1492 | ||
b3f980bd | 1493 | BUG_ON(vif->mmap_pages[pending_idx] == (void *)(~0UL)); |
f942dc25 IC |
1494 | |
1495 | /* Already complete? */ | |
b3f980bd | 1496 | if (vif->mmap_pages[pending_idx] == NULL) |
f942dc25 IC |
1497 | return; |
1498 | ||
b3f980bd | 1499 | pending_tx_info = &vif->pending_tx_info[pending_idx]; |
f942dc25 | 1500 | |
2810e5b9 | 1501 | head = pending_tx_info->head; |
f942dc25 | 1502 | |
b3f980bd WL |
1503 | BUG_ON(!pending_tx_is_head(vif, head)); |
1504 | BUG_ON(vif->pending_ring[pending_index(head)] != pending_idx); | |
f942dc25 | 1505 | |
2810e5b9 WL |
1506 | do { |
1507 | pending_ring_idx_t index; | |
1508 | pending_ring_idx_t idx = pending_index(head); | |
b3f980bd | 1509 | u16 info_idx = vif->pending_ring[idx]; |
f942dc25 | 1510 | |
b3f980bd | 1511 | pending_tx_info = &vif->pending_tx_info[info_idx]; |
2810e5b9 WL |
1512 | make_tx_response(vif, &pending_tx_info->req, status); |
1513 | ||
1514 | /* Setting any number other than | |
1515 | * INVALID_PENDING_RING_IDX indicates this slot is | |
1516 | * starting a new packet / ending a previous packet. | |
1517 | */ | |
1518 | pending_tx_info->head = 0; | |
1519 | ||
b3f980bd WL |
1520 | index = pending_index(vif->pending_prod++); |
1521 | vif->pending_ring[index] = vif->pending_ring[info_idx]; | |
f942dc25 | 1522 | |
b3f980bd | 1523 | peek = vif->pending_ring[pending_index(++head)]; |
2810e5b9 | 1524 | |
b3f980bd | 1525 | } while (!pending_tx_is_head(vif, peek)); |
2810e5b9 | 1526 | |
b3f980bd WL |
1527 | put_page(vif->mmap_pages[pending_idx]); |
1528 | vif->mmap_pages[pending_idx] = NULL; | |
f942dc25 IC |
1529 | } |
1530 | ||
2810e5b9 | 1531 | |
f942dc25 IC |
1532 | static void make_tx_response(struct xenvif *vif, |
1533 | struct xen_netif_tx_request *txp, | |
1534 | s8 st) | |
1535 | { | |
1536 | RING_IDX i = vif->tx.rsp_prod_pvt; | |
1537 | struct xen_netif_tx_response *resp; | |
1538 | int notify; | |
1539 | ||
1540 | resp = RING_GET_RESPONSE(&vif->tx, i); | |
1541 | resp->id = txp->id; | |
1542 | resp->status = st; | |
1543 | ||
1544 | if (txp->flags & XEN_NETTXF_extra_info) | |
1545 | RING_GET_RESPONSE(&vif->tx, ++i)->status = XEN_NETIF_RSP_NULL; | |
1546 | ||
1547 | vif->tx.rsp_prod_pvt = ++i; | |
1548 | RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&vif->tx, notify); | |
1549 | if (notify) | |
e1f00a69 | 1550 | notify_remote_via_irq(vif->tx_irq); |
f942dc25 IC |
1551 | } |
1552 | ||
1553 | static struct xen_netif_rx_response *make_rx_response(struct xenvif *vif, | |
1554 | u16 id, | |
1555 | s8 st, | |
1556 | u16 offset, | |
1557 | u16 size, | |
1558 | u16 flags) | |
1559 | { | |
1560 | RING_IDX i = vif->rx.rsp_prod_pvt; | |
1561 | struct xen_netif_rx_response *resp; | |
1562 | ||
1563 | resp = RING_GET_RESPONSE(&vif->rx, i); | |
1564 | resp->offset = offset; | |
1565 | resp->flags = flags; | |
1566 | resp->id = id; | |
1567 | resp->status = (s16)size; | |
1568 | if (st < 0) | |
1569 | resp->status = (s16)st; | |
1570 | ||
1571 | vif->rx.rsp_prod_pvt = ++i; | |
1572 | ||
1573 | return resp; | |
1574 | } | |
1575 | ||
b3f980bd | 1576 | static inline int rx_work_todo(struct xenvif *vif) |
f942dc25 | 1577 | { |
b3f980bd | 1578 | return !skb_queue_empty(&vif->rx_queue); |
f942dc25 IC |
1579 | } |
1580 | ||
b3f980bd | 1581 | static inline int tx_work_todo(struct xenvif *vif) |
f942dc25 IC |
1582 | { |
1583 | ||
b3f980bd WL |
1584 | if (likely(RING_HAS_UNCONSUMED_REQUESTS(&vif->tx)) && |
1585 | (nr_pending_reqs(vif) + XEN_NETBK_LEGACY_SLOTS_MAX | |
1586 | < MAX_PENDING_REQS)) | |
f942dc25 IC |
1587 | return 1; |
1588 | ||
1589 | return 0; | |
1590 | } | |
1591 | ||
7376419a | 1592 | void xenvif_unmap_frontend_rings(struct xenvif *vif) |
f942dc25 | 1593 | { |
c9d63699 DV |
1594 | if (vif->tx.sring) |
1595 | xenbus_unmap_ring_vfree(xenvif_to_xenbus_device(vif), | |
1596 | vif->tx.sring); | |
1597 | if (vif->rx.sring) | |
1598 | xenbus_unmap_ring_vfree(xenvif_to_xenbus_device(vif), | |
1599 | vif->rx.sring); | |
f942dc25 IC |
1600 | } |
1601 | ||
7376419a WL |
1602 | int xenvif_map_frontend_rings(struct xenvif *vif, |
1603 | grant_ref_t tx_ring_ref, | |
1604 | grant_ref_t rx_ring_ref) | |
f942dc25 | 1605 | { |
c9d63699 | 1606 | void *addr; |
f942dc25 IC |
1607 | struct xen_netif_tx_sring *txs; |
1608 | struct xen_netif_rx_sring *rxs; | |
1609 | ||
1610 | int err = -ENOMEM; | |
1611 | ||
c9d63699 DV |
1612 | err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(vif), |
1613 | tx_ring_ref, &addr); | |
1614 | if (err) | |
f942dc25 IC |
1615 | goto err; |
1616 | ||
c9d63699 | 1617 | txs = (struct xen_netif_tx_sring *)addr; |
f942dc25 IC |
1618 | BACK_RING_INIT(&vif->tx, txs, PAGE_SIZE); |
1619 | ||
c9d63699 DV |
1620 | err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(vif), |
1621 | rx_ring_ref, &addr); | |
1622 | if (err) | |
f942dc25 | 1623 | goto err; |
f942dc25 | 1624 | |
c9d63699 | 1625 | rxs = (struct xen_netif_rx_sring *)addr; |
f942dc25 IC |
1626 | BACK_RING_INIT(&vif->rx, rxs, PAGE_SIZE); |
1627 | ||
c9d63699 DV |
1628 | vif->rx_req_cons_peek = 0; |
1629 | ||
f942dc25 IC |
1630 | return 0; |
1631 | ||
1632 | err: | |
7376419a | 1633 | xenvif_unmap_frontend_rings(vif); |
f942dc25 IC |
1634 | return err; |
1635 | } | |
1636 | ||
7376419a | 1637 | int xenvif_kthread(void *data) |
b3f980bd WL |
1638 | { |
1639 | struct xenvif *vif = data; | |
1640 | ||
1641 | while (!kthread_should_stop()) { | |
1642 | wait_event_interruptible(vif->wq, | |
1643 | rx_work_todo(vif) || | |
1644 | kthread_should_stop()); | |
1645 | if (kthread_should_stop()) | |
1646 | break; | |
1647 | ||
1648 | if (rx_work_todo(vif)) | |
7376419a | 1649 | xenvif_rx_action(vif); |
b3f980bd WL |
1650 | |
1651 | cond_resched(); | |
1652 | } | |
1653 | ||
1654 | return 0; | |
1655 | } | |
1656 | ||
f942dc25 IC |
1657 | static int __init netback_init(void) |
1658 | { | |
f942dc25 | 1659 | int rc = 0; |
f942dc25 | 1660 | |
2a14b244 | 1661 | if (!xen_domain()) |
f942dc25 IC |
1662 | return -ENODEV; |
1663 | ||
37641494 | 1664 | if (fatal_skb_slots < XEN_NETBK_LEGACY_SLOTS_MAX) { |
383eda32 JP |
1665 | pr_info("fatal_skb_slots too small (%d), bump it to XEN_NETBK_LEGACY_SLOTS_MAX (%d)\n", |
1666 | fatal_skb_slots, XEN_NETBK_LEGACY_SLOTS_MAX); | |
37641494 | 1667 | fatal_skb_slots = XEN_NETBK_LEGACY_SLOTS_MAX; |
2810e5b9 WL |
1668 | } |
1669 | ||
f942dc25 IC |
1670 | rc = xenvif_xenbus_init(); |
1671 | if (rc) | |
1672 | goto failed_init; | |
1673 | ||
1674 | return 0; | |
1675 | ||
1676 | failed_init: | |
f942dc25 | 1677 | return rc; |
f942dc25 IC |
1678 | } |
1679 | ||
1680 | module_init(netback_init); | |
1681 | ||
b103f358 WL |
1682 | static void __exit netback_fini(void) |
1683 | { | |
b103f358 | 1684 | xenvif_xenbus_fini(); |
b103f358 WL |
1685 | } |
1686 | module_exit(netback_fini); | |
1687 | ||
f942dc25 | 1688 | MODULE_LICENSE("Dual BSD/GPL"); |
f984cec6 | 1689 | MODULE_ALIAS("xen-backend:vif"); |