Commit | Line | Data |
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e456a18a ED |
1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | #include <net/gro.h> | |
587652bb ED |
3 | #include <net/dst_metadata.h> |
4 | #include <net/busy_poll.h> | |
5 | #include <trace/events/net.h> | |
f6d827b1 | 6 | #include <linux/skbuff_ref.h> |
587652bb ED |
7 | |
8 | #define MAX_GRO_SKBS 8 | |
9 | ||
10 | /* This should be increased if a protocol with a bigger head is added. */ | |
11 | #define GRO_MAX_HEAD (MAX_HEADER + 128) | |
12 | ||
13 | static DEFINE_SPINLOCK(offload_lock); | |
587652bb ED |
14 | |
15 | /** | |
16 | * dev_add_offload - register offload handlers | |
17 | * @po: protocol offload declaration | |
18 | * | |
19 | * Add protocol offload handlers to the networking stack. The passed | |
20 | * &proto_offload is linked into kernel lists and may not be freed until | |
21 | * it has been removed from the kernel lists. | |
22 | * | |
23 | * This call does not sleep therefore it can not | |
24 | * guarantee all CPU's that are in middle of receiving packets | |
25 | * will see the new offload handlers (until the next received packet). | |
26 | */ | |
27 | void dev_add_offload(struct packet_offload *po) | |
28 | { | |
29 | struct packet_offload *elem; | |
30 | ||
31 | spin_lock(&offload_lock); | |
2658b5a8 | 32 | list_for_each_entry(elem, &net_hotdata.offload_base, list) { |
587652bb ED |
33 | if (po->priority < elem->priority) |
34 | break; | |
35 | } | |
36 | list_add_rcu(&po->list, elem->list.prev); | |
37 | spin_unlock(&offload_lock); | |
38 | } | |
39 | EXPORT_SYMBOL(dev_add_offload); | |
40 | ||
41 | /** | |
42 | * __dev_remove_offload - remove offload handler | |
43 | * @po: packet offload declaration | |
44 | * | |
45 | * Remove a protocol offload handler that was previously added to the | |
46 | * kernel offload handlers by dev_add_offload(). The passed &offload_type | |
47 | * is removed from the kernel lists and can be freed or reused once this | |
48 | * function returns. | |
49 | * | |
50 | * The packet type might still be in use by receivers | |
51 | * and must not be freed until after all the CPU's have gone | |
52 | * through a quiescent state. | |
53 | */ | |
54 | static void __dev_remove_offload(struct packet_offload *po) | |
55 | { | |
2658b5a8 | 56 | struct list_head *head = &net_hotdata.offload_base; |
587652bb ED |
57 | struct packet_offload *po1; |
58 | ||
59 | spin_lock(&offload_lock); | |
60 | ||
61 | list_for_each_entry(po1, head, list) { | |
62 | if (po == po1) { | |
63 | list_del_rcu(&po->list); | |
64 | goto out; | |
65 | } | |
66 | } | |
67 | ||
68 | pr_warn("dev_remove_offload: %p not found\n", po); | |
69 | out: | |
70 | spin_unlock(&offload_lock); | |
71 | } | |
72 | ||
73 | /** | |
74 | * dev_remove_offload - remove packet offload handler | |
75 | * @po: packet offload declaration | |
76 | * | |
77 | * Remove a packet offload handler that was previously added to the kernel | |
78 | * offload handlers by dev_add_offload(). The passed &offload_type is | |
79 | * removed from the kernel lists and can be freed or reused once this | |
80 | * function returns. | |
81 | * | |
82 | * This call sleeps to guarantee that no CPU is looking at the packet | |
83 | * type after return. | |
84 | */ | |
85 | void dev_remove_offload(struct packet_offload *po) | |
86 | { | |
87 | __dev_remove_offload(po); | |
88 | ||
89 | synchronize_net(); | |
90 | } | |
91 | EXPORT_SYMBOL(dev_remove_offload); | |
92 | ||
e456a18a ED |
93 | |
94 | int skb_gro_receive(struct sk_buff *p, struct sk_buff *skb) | |
95 | { | |
96 | struct skb_shared_info *pinfo, *skbinfo = skb_shinfo(skb); | |
97 | unsigned int offset = skb_gro_offset(skb); | |
98 | unsigned int headlen = skb_headlen(skb); | |
99 | unsigned int len = skb_gro_len(skb); | |
100 | unsigned int delta_truesize; | |
eac1b93c | 101 | unsigned int gro_max_size; |
e456a18a ED |
102 | unsigned int new_truesize; |
103 | struct sk_buff *lp; | |
5eddb249 | 104 | int segs; |
e456a18a | 105 | |
7d2c89b3 AD |
106 | /* Do not splice page pool based packets w/ non-page pool |
107 | * packets. This can result in reference count issues as page | |
108 | * pool pages will not decrement the reference count and will | |
109 | * instead be immediately returned to the pool or have frag | |
110 | * count decremented. | |
111 | */ | |
112 | if (p->pp_recycle != skb->pp_recycle) | |
113 | return -ETOOMANYREFS; | |
114 | ||
b1a78b9b XL |
115 | /* pairs with WRITE_ONCE() in netif_set_gro(_ipv4)_max_size() */ |
116 | gro_max_size = p->protocol == htons(ETH_P_IPV6) ? | |
117 | READ_ONCE(p->dev->gro_max_size) : | |
82b4a941 | 118 | READ_ONCE(p->dev->gro_ipv4_max_size); |
eac1b93c CL |
119 | |
120 | if (unlikely(p->len + len >= gro_max_size || NAPI_GRO_CB(skb)->flush)) | |
e456a18a ED |
121 | return -E2BIG; |
122 | ||
0fe79f28 | 123 | if (unlikely(p->len + len >= GRO_LEGACY_MAX_SIZE)) { |
b1a78b9b XL |
124 | if (NAPI_GRO_CB(skb)->proto != IPPROTO_TCP || |
125 | (p->protocol == htons(ETH_P_IPV6) && | |
126 | skb_headroom(p) < sizeof(struct hop_jumbo_hdr)) || | |
0fe79f28 AD |
127 | p->encapsulation) |
128 | return -E2BIG; | |
129 | } | |
130 | ||
5eddb249 | 131 | segs = NAPI_GRO_CB(skb)->count; |
e456a18a ED |
132 | lp = NAPI_GRO_CB(p)->last; |
133 | pinfo = skb_shinfo(lp); | |
134 | ||
135 | if (headlen <= offset) { | |
136 | skb_frag_t *frag; | |
137 | skb_frag_t *frag2; | |
138 | int i = skbinfo->nr_frags; | |
139 | int nr_frags = pinfo->nr_frags + i; | |
140 | ||
141 | if (nr_frags > MAX_SKB_FRAGS) | |
142 | goto merge; | |
143 | ||
144 | offset -= headlen; | |
145 | pinfo->nr_frags = nr_frags; | |
146 | skbinfo->nr_frags = 0; | |
147 | ||
148 | frag = pinfo->frags + nr_frags; | |
149 | frag2 = skbinfo->frags + i; | |
150 | do { | |
151 | *--frag = *--frag2; | |
152 | } while (--i); | |
153 | ||
154 | skb_frag_off_add(frag, offset); | |
155 | skb_frag_size_sub(frag, offset); | |
156 | ||
157 | /* all fragments truesize : remove (head size + sk_buff) */ | |
158 | new_truesize = SKB_TRUESIZE(skb_end_offset(skb)); | |
159 | delta_truesize = skb->truesize - new_truesize; | |
160 | ||
161 | skb->truesize = new_truesize; | |
162 | skb->len -= skb->data_len; | |
163 | skb->data_len = 0; | |
164 | ||
165 | NAPI_GRO_CB(skb)->free = NAPI_GRO_FREE; | |
166 | goto done; | |
167 | } else if (skb->head_frag) { | |
168 | int nr_frags = pinfo->nr_frags; | |
169 | skb_frag_t *frag = pinfo->frags + nr_frags; | |
170 | struct page *page = virt_to_head_page(skb->head); | |
171 | unsigned int first_size = headlen - offset; | |
172 | unsigned int first_offset; | |
173 | ||
174 | if (nr_frags + 1 + skbinfo->nr_frags > MAX_SKB_FRAGS) | |
175 | goto merge; | |
176 | ||
177 | first_offset = skb->data - | |
178 | (unsigned char *)page_address(page) + | |
179 | offset; | |
180 | ||
181 | pinfo->nr_frags = nr_frags + 1 + skbinfo->nr_frags; | |
182 | ||
b51f4113 | 183 | skb_frag_fill_page_desc(frag, page, first_offset, first_size); |
e456a18a ED |
184 | |
185 | memcpy(frag + 1, skbinfo->frags, sizeof(*frag) * skbinfo->nr_frags); | |
186 | /* We dont need to clear skbinfo->nr_frags here */ | |
187 | ||
188 | new_truesize = SKB_DATA_ALIGN(sizeof(struct sk_buff)); | |
189 | delta_truesize = skb->truesize - new_truesize; | |
190 | skb->truesize = new_truesize; | |
191 | NAPI_GRO_CB(skb)->free = NAPI_GRO_FREE_STOLEN_HEAD; | |
192 | goto done; | |
193 | } | |
194 | ||
195 | merge: | |
ed4cccef | 196 | /* sk ownership - if any - completely transferred to the aggregated packet */ |
e456a18a | 197 | skb->destructor = NULL; |
ed4cccef | 198 | skb->sk = NULL; |
e456a18a ED |
199 | delta_truesize = skb->truesize; |
200 | if (offset > headlen) { | |
201 | unsigned int eat = offset - headlen; | |
202 | ||
203 | skb_frag_off_add(&skbinfo->frags[0], eat); | |
204 | skb_frag_size_sub(&skbinfo->frags[0], eat); | |
205 | skb->data_len -= eat; | |
206 | skb->len -= eat; | |
207 | offset = headlen; | |
208 | } | |
209 | ||
210 | __skb_pull(skb, offset); | |
211 | ||
212 | if (NAPI_GRO_CB(p)->last == p) | |
213 | skb_shinfo(p)->frag_list = skb; | |
214 | else | |
215 | NAPI_GRO_CB(p)->last->next = skb; | |
216 | NAPI_GRO_CB(p)->last = skb; | |
217 | __skb_header_release(skb); | |
218 | lp = p; | |
219 | ||
220 | done: | |
5eddb249 | 221 | NAPI_GRO_CB(p)->count += segs; |
e456a18a ED |
222 | p->data_len += len; |
223 | p->truesize += delta_truesize; | |
224 | p->len += len; | |
225 | if (lp != p) { | |
226 | lp->data_len += len; | |
227 | lp->truesize += delta_truesize; | |
228 | lp->len += len; | |
229 | } | |
230 | NAPI_GRO_CB(skb)->same_flow = 1; | |
231 | return 0; | |
232 | } | |
587652bb | 233 | |
8928756d FF |
234 | int skb_gro_receive_list(struct sk_buff *p, struct sk_buff *skb) |
235 | { | |
236 | if (unlikely(p->len + skb->len >= 65536)) | |
237 | return -E2BIG; | |
238 | ||
239 | if (NAPI_GRO_CB(p)->last == p) | |
240 | skb_shinfo(p)->frag_list = skb; | |
241 | else | |
242 | NAPI_GRO_CB(p)->last->next = skb; | |
243 | ||
244 | skb_pull(skb, skb_gro_offset(skb)); | |
245 | ||
246 | NAPI_GRO_CB(p)->last = skb; | |
247 | NAPI_GRO_CB(p)->count++; | |
248 | p->data_len += skb->len; | |
249 | ||
250 | /* sk ownership - if any - completely transferred to the aggregated packet */ | |
251 | skb->destructor = NULL; | |
252 | skb->sk = NULL; | |
253 | p->truesize += skb->truesize; | |
254 | p->len += skb->len; | |
255 | ||
256 | NAPI_GRO_CB(skb)->same_flow = 1; | |
257 | ||
258 | return 0; | |
259 | } | |
260 | ||
587652bb ED |
261 | |
262 | static void napi_gro_complete(struct napi_struct *napi, struct sk_buff *skb) | |
263 | { | |
2658b5a8 | 264 | struct list_head *head = &net_hotdata.offload_base; |
587652bb ED |
265 | struct packet_offload *ptype; |
266 | __be16 type = skb->protocol; | |
587652bb ED |
267 | int err = -ENOENT; |
268 | ||
269 | BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb)); | |
270 | ||
271 | if (NAPI_GRO_CB(skb)->count == 1) { | |
272 | skb_shinfo(skb)->gso_size = 0; | |
273 | goto out; | |
274 | } | |
275 | ||
276 | rcu_read_lock(); | |
277 | list_for_each_entry_rcu(ptype, head, list) { | |
278 | if (ptype->type != type || !ptype->callbacks.gro_complete) | |
279 | continue; | |
280 | ||
281 | err = INDIRECT_CALL_INET(ptype->callbacks.gro_complete, | |
282 | ipv6_gro_complete, inet_gro_complete, | |
283 | skb, 0); | |
284 | break; | |
285 | } | |
286 | rcu_read_unlock(); | |
287 | ||
288 | if (err) { | |
289 | WARN_ON(&ptype->list == head); | |
290 | kfree_skb(skb); | |
291 | return; | |
292 | } | |
293 | ||
294 | out: | |
295 | gro_normal_one(napi, skb, NAPI_GRO_CB(skb)->count); | |
296 | } | |
297 | ||
298 | static void __napi_gro_flush_chain(struct napi_struct *napi, u32 index, | |
299 | bool flush_old) | |
300 | { | |
301 | struct list_head *head = &napi->gro_hash[index].list; | |
302 | struct sk_buff *skb, *p; | |
303 | ||
304 | list_for_each_entry_safe_reverse(skb, p, head, list) { | |
305 | if (flush_old && NAPI_GRO_CB(skb)->age == jiffies) | |
306 | return; | |
307 | skb_list_del_init(skb); | |
308 | napi_gro_complete(napi, skb); | |
309 | napi->gro_hash[index].count--; | |
310 | } | |
311 | ||
312 | if (!napi->gro_hash[index].count) | |
313 | __clear_bit(index, &napi->gro_bitmask); | |
314 | } | |
315 | ||
316 | /* napi->gro_hash[].list contains packets ordered by age. | |
317 | * youngest packets at the head of it. | |
318 | * Complete skbs in reverse order to reduce latencies. | |
319 | */ | |
320 | void napi_gro_flush(struct napi_struct *napi, bool flush_old) | |
321 | { | |
322 | unsigned long bitmask = napi->gro_bitmask; | |
323 | unsigned int i, base = ~0U; | |
324 | ||
325 | while ((i = ffs(bitmask)) != 0) { | |
326 | bitmask >>= i; | |
327 | base += i; | |
328 | __napi_gro_flush_chain(napi, base, flush_old); | |
329 | } | |
330 | } | |
331 | EXPORT_SYMBOL(napi_gro_flush); | |
332 | ||
2dc6af8b JK |
333 | static unsigned long gro_list_prepare_tc_ext(const struct sk_buff *skb, |
334 | const struct sk_buff *p, | |
335 | unsigned long diffs) | |
336 | { | |
337 | #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT) | |
338 | struct tc_skb_ext *skb_ext; | |
339 | struct tc_skb_ext *p_ext; | |
340 | ||
341 | skb_ext = skb_ext_find(skb, TC_SKB_EXT); | |
342 | p_ext = skb_ext_find(p, TC_SKB_EXT); | |
343 | ||
344 | diffs |= (!!p_ext) ^ (!!skb_ext); | |
345 | if (!diffs && unlikely(skb_ext)) | |
346 | diffs |= p_ext->chain ^ skb_ext->chain; | |
347 | #endif | |
348 | return diffs; | |
349 | } | |
350 | ||
587652bb ED |
351 | static void gro_list_prepare(const struct list_head *head, |
352 | const struct sk_buff *skb) | |
353 | { | |
354 | unsigned int maclen = skb->dev->hard_header_len; | |
355 | u32 hash = skb_get_hash_raw(skb); | |
356 | struct sk_buff *p; | |
357 | ||
358 | list_for_each_entry(p, head, list) { | |
359 | unsigned long diffs; | |
360 | ||
587652bb ED |
361 | if (hash != skb_get_hash_raw(p)) { |
362 | NAPI_GRO_CB(p)->same_flow = 0; | |
363 | continue; | |
364 | } | |
365 | ||
366 | diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev; | |
be3ed486 | 367 | diffs |= p->vlan_all ^ skb->vlan_all; |
587652bb ED |
368 | diffs |= skb_metadata_differs(p, skb); |
369 | if (maclen == ETH_HLEN) | |
370 | diffs |= compare_ether_header(skb_mac_header(p), | |
371 | skb_mac_header(skb)); | |
372 | else if (!diffs) | |
373 | diffs = memcmp(skb_mac_header(p), | |
374 | skb_mac_header(skb), | |
375 | maclen); | |
376 | ||
377 | /* in most common scenarions 'slow_gro' is 0 | |
378 | * otherwise we are already on some slower paths | |
379 | * either skip all the infrequent tests altogether or | |
380 | * avoid trying too hard to skip each of them individually | |
381 | */ | |
382 | if (!diffs && unlikely(skb->slow_gro | p->slow_gro)) { | |
587652bb ED |
383 | diffs |= p->sk != skb->sk; |
384 | diffs |= skb_metadata_dst_cmp(p, skb); | |
385 | diffs |= skb_get_nfct(p) ^ skb_get_nfct(skb); | |
386 | ||
2dc6af8b | 387 | diffs |= gro_list_prepare_tc_ext(skb, p, diffs); |
587652bb ED |
388 | } |
389 | ||
390 | NAPI_GRO_CB(p)->same_flow = !diffs; | |
391 | } | |
392 | } | |
393 | ||
394 | static inline void skb_gro_reset_offset(struct sk_buff *skb, u32 nhoff) | |
395 | { | |
c7583e9f ED |
396 | const struct skb_shared_info *pinfo; |
397 | const skb_frag_t *frag0; | |
398 | unsigned int headlen; | |
587652bb | 399 | |
5ef31ea5 | 400 | NAPI_GRO_CB(skb)->network_offset = 0; |
587652bb | 401 | NAPI_GRO_CB(skb)->data_offset = 0; |
c7583e9f ED |
402 | headlen = skb_headlen(skb); |
403 | NAPI_GRO_CB(skb)->frag0 = skb->data; | |
404 | NAPI_GRO_CB(skb)->frag0_len = headlen; | |
405 | if (headlen) | |
406 | return; | |
407 | ||
408 | pinfo = skb_shinfo(skb); | |
409 | frag0 = &pinfo->frags[0]; | |
587652bb | 410 | |
c7583e9f | 411 | if (pinfo->nr_frags && !PageHighMem(skb_frag_page(frag0)) && |
587652bb ED |
412 | (!NET_IP_ALIGN || !((skb_frag_off(frag0) + nhoff) & 3))) { |
413 | NAPI_GRO_CB(skb)->frag0 = skb_frag_address(frag0); | |
414 | NAPI_GRO_CB(skb)->frag0_len = min_t(unsigned int, | |
415 | skb_frag_size(frag0), | |
416 | skb->end - skb->tail); | |
417 | } | |
418 | } | |
419 | ||
420 | static void gro_pull_from_frag0(struct sk_buff *skb, int grow) | |
421 | { | |
422 | struct skb_shared_info *pinfo = skb_shinfo(skb); | |
423 | ||
424 | BUG_ON(skb->end - skb->tail < grow); | |
425 | ||
426 | memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow); | |
427 | ||
428 | skb->data_len -= grow; | |
429 | skb->tail += grow; | |
430 | ||
431 | skb_frag_off_add(&pinfo->frags[0], grow); | |
432 | skb_frag_size_sub(&pinfo->frags[0], grow); | |
433 | ||
434 | if (unlikely(!skb_frag_size(&pinfo->frags[0]))) { | |
435 | skb_frag_unref(skb, 0); | |
436 | memmove(pinfo->frags, pinfo->frags + 1, | |
437 | --pinfo->nr_frags * sizeof(pinfo->frags[0])); | |
438 | } | |
439 | } | |
440 | ||
7b355b76 RG |
441 | static void gro_try_pull_from_frag0(struct sk_buff *skb) |
442 | { | |
443 | int grow = skb_gro_offset(skb) - skb_headlen(skb); | |
444 | ||
445 | if (grow > 0) | |
446 | gro_pull_from_frag0(skb, grow); | |
447 | } | |
448 | ||
587652bb ED |
449 | static void gro_flush_oldest(struct napi_struct *napi, struct list_head *head) |
450 | { | |
451 | struct sk_buff *oldest; | |
452 | ||
453 | oldest = list_last_entry(head, struct sk_buff, list); | |
454 | ||
455 | /* We are called with head length >= MAX_GRO_SKBS, so this is | |
456 | * impossible. | |
457 | */ | |
458 | if (WARN_ON_ONCE(!oldest)) | |
459 | return; | |
460 | ||
461 | /* Do not adjust napi->gro_hash[].count, caller is adding a new | |
462 | * SKB to the chain. | |
463 | */ | |
464 | skb_list_del_init(oldest); | |
465 | napi_gro_complete(napi, oldest); | |
466 | } | |
467 | ||
468 | static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb) | |
469 | { | |
470 | u32 bucket = skb_get_hash_raw(skb) & (GRO_HASH_BUCKETS - 1); | |
471 | struct gro_list *gro_list = &napi->gro_hash[bucket]; | |
2658b5a8 | 472 | struct list_head *head = &net_hotdata.offload_base; |
587652bb ED |
473 | struct packet_offload *ptype; |
474 | __be16 type = skb->protocol; | |
475 | struct sk_buff *pp = NULL; | |
476 | enum gro_result ret; | |
477 | int same_flow; | |
587652bb ED |
478 | |
479 | if (netif_elide_gro(skb->dev)) | |
480 | goto normal; | |
481 | ||
482 | gro_list_prepare(&gro_list->list, skb); | |
483 | ||
484 | rcu_read_lock(); | |
485 | list_for_each_entry_rcu(ptype, head, list) { | |
e081ecf0 RG |
486 | if (ptype->type == type && ptype->callbacks.gro_receive) |
487 | goto found_ptype; | |
488 | } | |
489 | rcu_read_unlock(); | |
490 | goto normal; | |
491 | ||
492 | found_ptype: | |
493 | skb_set_network_header(skb, skb_gro_offset(skb)); | |
494 | skb_reset_mac_len(skb); | |
495 | BUILD_BUG_ON(sizeof_field(struct napi_gro_cb, zeroed) != sizeof(u32)); | |
496 | BUILD_BUG_ON(!IS_ALIGNED(offsetof(struct napi_gro_cb, zeroed), | |
497 | sizeof(u32))); /* Avoid slow unaligned acc */ | |
498 | *(u32 *)&NAPI_GRO_CB(skb)->zeroed = 0; | |
499 | NAPI_GRO_CB(skb)->flush = skb_has_frag_list(skb); | |
e081ecf0 RG |
500 | NAPI_GRO_CB(skb)->count = 1; |
501 | if (unlikely(skb_is_gso(skb))) { | |
502 | NAPI_GRO_CB(skb)->count = skb_shinfo(skb)->gso_segs; | |
7871f54e ED |
503 | /* Only support TCP and non DODGY users. */ |
504 | if (!skb_is_gso_tcp(skb) || | |
505 | (skb_shinfo(skb)->gso_type & SKB_GSO_DODGY)) | |
e081ecf0 RG |
506 | NAPI_GRO_CB(skb)->flush = 1; |
507 | } | |
587652bb | 508 | |
e081ecf0 RG |
509 | /* Setup for GRO checksum validation */ |
510 | switch (skb->ip_summed) { | |
511 | case CHECKSUM_COMPLETE: | |
512 | NAPI_GRO_CB(skb)->csum = skb->csum; | |
513 | NAPI_GRO_CB(skb)->csum_valid = 1; | |
514 | break; | |
515 | case CHECKSUM_UNNECESSARY: | |
516 | NAPI_GRO_CB(skb)->csum_cnt = skb->csum_level + 1; | |
587652bb ED |
517 | break; |
518 | } | |
587652bb | 519 | |
e081ecf0 RG |
520 | pp = INDIRECT_CALL_INET(ptype->callbacks.gro_receive, |
521 | ipv6_gro_receive, inet_gro_receive, | |
522 | &gro_list->list, skb); | |
523 | ||
524 | rcu_read_unlock(); | |
587652bb ED |
525 | |
526 | if (PTR_ERR(pp) == -EINPROGRESS) { | |
527 | ret = GRO_CONSUMED; | |
528 | goto ok; | |
529 | } | |
530 | ||
531 | same_flow = NAPI_GRO_CB(skb)->same_flow; | |
532 | ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED; | |
533 | ||
534 | if (pp) { | |
535 | skb_list_del_init(pp); | |
536 | napi_gro_complete(napi, pp); | |
537 | gro_list->count--; | |
538 | } | |
539 | ||
540 | if (same_flow) | |
541 | goto ok; | |
542 | ||
543 | if (NAPI_GRO_CB(skb)->flush) | |
544 | goto normal; | |
545 | ||
546 | if (unlikely(gro_list->count >= MAX_GRO_SKBS)) | |
547 | gro_flush_oldest(napi, &gro_list->list); | |
548 | else | |
549 | gro_list->count++; | |
550 | ||
7b355b76 RG |
551 | /* Must be called before setting NAPI_GRO_CB(skb)->{age|last} */ |
552 | gro_try_pull_from_frag0(skb); | |
587652bb ED |
553 | NAPI_GRO_CB(skb)->age = jiffies; |
554 | NAPI_GRO_CB(skb)->last = skb; | |
5eddb249 CL |
555 | if (!skb_is_gso(skb)) |
556 | skb_shinfo(skb)->gso_size = skb_gro_len(skb); | |
587652bb ED |
557 | list_add(&skb->list, &gro_list->list); |
558 | ret = GRO_HELD; | |
587652bb ED |
559 | ok: |
560 | if (gro_list->count) { | |
561 | if (!test_bit(bucket, &napi->gro_bitmask)) | |
562 | __set_bit(bucket, &napi->gro_bitmask); | |
563 | } else if (test_bit(bucket, &napi->gro_bitmask)) { | |
564 | __clear_bit(bucket, &napi->gro_bitmask); | |
565 | } | |
566 | ||
567 | return ret; | |
568 | ||
569 | normal: | |
570 | ret = GRO_NORMAL; | |
7b355b76 RG |
571 | gro_try_pull_from_frag0(skb); |
572 | goto ok; | |
587652bb ED |
573 | } |
574 | ||
575 | struct packet_offload *gro_find_receive_by_type(__be16 type) | |
576 | { | |
2658b5a8 | 577 | struct list_head *offload_head = &net_hotdata.offload_base; |
587652bb ED |
578 | struct packet_offload *ptype; |
579 | ||
580 | list_for_each_entry_rcu(ptype, offload_head, list) { | |
581 | if (ptype->type != type || !ptype->callbacks.gro_receive) | |
582 | continue; | |
583 | return ptype; | |
584 | } | |
585 | return NULL; | |
586 | } | |
587 | EXPORT_SYMBOL(gro_find_receive_by_type); | |
588 | ||
589 | struct packet_offload *gro_find_complete_by_type(__be16 type) | |
590 | { | |
2658b5a8 | 591 | struct list_head *offload_head = &net_hotdata.offload_base; |
587652bb ED |
592 | struct packet_offload *ptype; |
593 | ||
594 | list_for_each_entry_rcu(ptype, offload_head, list) { | |
595 | if (ptype->type != type || !ptype->callbacks.gro_complete) | |
596 | continue; | |
597 | return ptype; | |
598 | } | |
599 | return NULL; | |
600 | } | |
601 | EXPORT_SYMBOL(gro_find_complete_by_type); | |
602 | ||
603 | static gro_result_t napi_skb_finish(struct napi_struct *napi, | |
604 | struct sk_buff *skb, | |
605 | gro_result_t ret) | |
606 | { | |
607 | switch (ret) { | |
608 | case GRO_NORMAL: | |
609 | gro_normal_one(napi, skb, 1); | |
610 | break; | |
611 | ||
612 | case GRO_MERGED_FREE: | |
613 | if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD) | |
614 | napi_skb_free_stolen_head(skb); | |
615 | else if (skb->fclone != SKB_FCLONE_UNAVAILABLE) | |
616 | __kfree_skb(skb); | |
617 | else | |
8fa66e4a | 618 | __napi_kfree_skb(skb, SKB_CONSUMED); |
587652bb ED |
619 | break; |
620 | ||
621 | case GRO_HELD: | |
622 | case GRO_MERGED: | |
623 | case GRO_CONSUMED: | |
624 | break; | |
625 | } | |
626 | ||
627 | return ret; | |
628 | } | |
629 | ||
630 | gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb) | |
631 | { | |
632 | gro_result_t ret; | |
633 | ||
634 | skb_mark_napi_id(skb, napi); | |
635 | trace_napi_gro_receive_entry(skb); | |
636 | ||
637 | skb_gro_reset_offset(skb, 0); | |
638 | ||
639 | ret = napi_skb_finish(napi, skb, dev_gro_receive(napi, skb)); | |
640 | trace_napi_gro_receive_exit(ret); | |
641 | ||
642 | return ret; | |
643 | } | |
644 | EXPORT_SYMBOL(napi_gro_receive); | |
645 | ||
646 | static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb) | |
647 | { | |
648 | if (unlikely(skb->pfmemalloc)) { | |
649 | consume_skb(skb); | |
650 | return; | |
651 | } | |
652 | __skb_pull(skb, skb_headlen(skb)); | |
653 | /* restore the reserve we had after netdev_alloc_skb_ip_align() */ | |
654 | skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb)); | |
655 | __vlan_hwaccel_clear_tag(skb); | |
656 | skb->dev = napi->dev; | |
657 | skb->skb_iif = 0; | |
658 | ||
659 | /* eth_type_trans() assumes pkt_type is PACKET_HOST */ | |
660 | skb->pkt_type = PACKET_HOST; | |
661 | ||
662 | skb->encapsulation = 0; | |
663 | skb_shinfo(skb)->gso_type = 0; | |
5eddb249 | 664 | skb_shinfo(skb)->gso_size = 0; |
587652bb ED |
665 | if (unlikely(skb->slow_gro)) { |
666 | skb_orphan(skb); | |
667 | skb_ext_reset(skb); | |
668 | nf_reset_ct(skb); | |
669 | skb->slow_gro = 0; | |
670 | } | |
671 | ||
672 | napi->skb = skb; | |
673 | } | |
674 | ||
675 | struct sk_buff *napi_get_frags(struct napi_struct *napi) | |
676 | { | |
677 | struct sk_buff *skb = napi->skb; | |
678 | ||
679 | if (!skb) { | |
680 | skb = napi_alloc_skb(napi, GRO_MAX_HEAD); | |
681 | if (skb) { | |
682 | napi->skb = skb; | |
683 | skb_mark_napi_id(skb, napi); | |
684 | } | |
685 | } | |
686 | return skb; | |
687 | } | |
688 | EXPORT_SYMBOL(napi_get_frags); | |
689 | ||
690 | static gro_result_t napi_frags_finish(struct napi_struct *napi, | |
691 | struct sk_buff *skb, | |
692 | gro_result_t ret) | |
693 | { | |
694 | switch (ret) { | |
695 | case GRO_NORMAL: | |
696 | case GRO_HELD: | |
697 | __skb_push(skb, ETH_HLEN); | |
698 | skb->protocol = eth_type_trans(skb, skb->dev); | |
699 | if (ret == GRO_NORMAL) | |
700 | gro_normal_one(napi, skb, 1); | |
701 | break; | |
702 | ||
703 | case GRO_MERGED_FREE: | |
704 | if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD) | |
705 | napi_skb_free_stolen_head(skb); | |
706 | else | |
707 | napi_reuse_skb(napi, skb); | |
708 | break; | |
709 | ||
710 | case GRO_MERGED: | |
711 | case GRO_CONSUMED: | |
712 | break; | |
713 | } | |
714 | ||
715 | return ret; | |
716 | } | |
717 | ||
718 | /* Upper GRO stack assumes network header starts at gro_offset=0 | |
719 | * Drivers could call both napi_gro_frags() and napi_gro_receive() | |
720 | * We copy ethernet header into skb->data to have a common layout. | |
721 | */ | |
722 | static struct sk_buff *napi_frags_skb(struct napi_struct *napi) | |
723 | { | |
724 | struct sk_buff *skb = napi->skb; | |
725 | const struct ethhdr *eth; | |
726 | unsigned int hlen = sizeof(*eth); | |
727 | ||
728 | napi->skb = NULL; | |
729 | ||
730 | skb_reset_mac_header(skb); | |
731 | skb_gro_reset_offset(skb, hlen); | |
732 | ||
93e16ea0 | 733 | if (unlikely(!skb_gro_may_pull(skb, hlen))) { |
587652bb ED |
734 | eth = skb_gro_header_slow(skb, hlen, 0); |
735 | if (unlikely(!eth)) { | |
736 | net_warn_ratelimited("%s: dropping impossible skb from %s\n", | |
737 | __func__, napi->dev->name); | |
738 | napi_reuse_skb(napi, skb); | |
739 | return NULL; | |
740 | } | |
741 | } else { | |
742 | eth = (const struct ethhdr *)skb->data; | |
c7583e9f ED |
743 | |
744 | if (NAPI_GRO_CB(skb)->frag0 != skb->data) | |
745 | gro_pull_from_frag0(skb, hlen); | |
746 | ||
587652bb ED |
747 | NAPI_GRO_CB(skb)->frag0 += hlen; |
748 | NAPI_GRO_CB(skb)->frag0_len -= hlen; | |
749 | } | |
750 | __skb_pull(skb, hlen); | |
751 | ||
752 | /* | |
753 | * This works because the only protocols we care about don't require | |
754 | * special handling. | |
755 | * We'll fix it up properly in napi_frags_finish() | |
756 | */ | |
757 | skb->protocol = eth->h_proto; | |
758 | ||
759 | return skb; | |
760 | } | |
761 | ||
762 | gro_result_t napi_gro_frags(struct napi_struct *napi) | |
763 | { | |
764 | gro_result_t ret; | |
765 | struct sk_buff *skb = napi_frags_skb(napi); | |
766 | ||
767 | trace_napi_gro_frags_entry(skb); | |
768 | ||
769 | ret = napi_frags_finish(napi, skb, dev_gro_receive(napi, skb)); | |
770 | trace_napi_gro_frags_exit(ret); | |
771 | ||
772 | return ret; | |
773 | } | |
774 | EXPORT_SYMBOL(napi_gro_frags); | |
775 | ||
776 | /* Compute the checksum from gro_offset and return the folded value | |
777 | * after adding in any pseudo checksum. | |
778 | */ | |
779 | __sum16 __skb_gro_checksum_complete(struct sk_buff *skb) | |
780 | { | |
781 | __wsum wsum; | |
782 | __sum16 sum; | |
783 | ||
784 | wsum = skb_checksum(skb, skb_gro_offset(skb), skb_gro_len(skb), 0); | |
785 | ||
786 | /* NAPI_GRO_CB(skb)->csum holds pseudo checksum */ | |
787 | sum = csum_fold(csum_add(NAPI_GRO_CB(skb)->csum, wsum)); | |
788 | /* See comments in __skb_checksum_complete(). */ | |
789 | if (likely(!sum)) { | |
790 | if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE) && | |
791 | !skb->csum_complete_sw) | |
792 | netdev_rx_csum_fault(skb->dev, skb); | |
793 | } | |
794 | ||
795 | NAPI_GRO_CB(skb)->csum = wsum; | |
796 | NAPI_GRO_CB(skb)->csum_valid = 1; | |
797 | ||
798 | return sum; | |
799 | } | |
800 | EXPORT_SYMBOL(__skb_gro_checksum_complete); |