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1/* SPDX-License-Identifier: GPL-2.0-or-later */
2
3#ifndef _NET_GRO_H
4#define _NET_GRO_H
5
6#include <linux/indirect_call_wrapper.h>
7#include <linux/ip.h>
8#include <linux/ipv6.h>
9#include <net/ip6_checksum.h>
10#include <linux/skbuff.h>
11#include <net/udp.h>
12#include <net/hotdata.h>
13
14struct napi_gro_cb {
15 union {
16 struct {
17 /* Virtual address of skb_shinfo(skb)->frags[0].page + offset. */
18 void *frag0;
19
20 /* Length of frag0. */
21 unsigned int frag0_len;
22 };
23
24 struct {
25 /* used in skb_gro_receive() slow path */
26 struct sk_buff *last;
27
28 /* jiffies when first packet was created/queued */
29 unsigned long age;
30 };
31 };
32
33 /* This indicates where we are processing relative to skb->data. */
34 int data_offset;
35
36 /* This is non-zero if the packet cannot be merged with the new skb. */
37 u16 flush;
38
39 /* Save the IP ID here and check when we get to the transport layer */
40 u16 flush_id;
41
42 /* Number of segments aggregated. */
43 u16 count;
44
45 /* Used in ipv6_gro_receive() and foo-over-udp and esp-in-udp */
46 u16 proto;
47
48/* Used in napi_gro_cb::free */
49#define NAPI_GRO_FREE 1
50#define NAPI_GRO_FREE_STOLEN_HEAD 2
51 /* portion of the cb set to zero at every gro iteration */
52 struct_group(zeroed,
53
54 /* Start offset for remote checksum offload */
55 u16 gro_remcsum_start;
56
57 /* This is non-zero if the packet may be of the same flow. */
58 u8 same_flow:1;
59
60 /* Used in tunnel GRO receive */
61 u8 encap_mark:1;
62
63 /* GRO checksum is valid */
64 u8 csum_valid:1;
65
66 /* Number of checksums via CHECKSUM_UNNECESSARY */
67 u8 csum_cnt:3;
68
69 /* Free the skb? */
70 u8 free:2;
71
72 /* Used in foo-over-udp, set in udp[46]_gro_receive */
73 u8 is_ipv6:1;
74
75 /* Used in GRE, set in fou/gue_gro_receive */
76 u8 is_fou:1;
77
78 /* Used to determine if flush_id can be ignored */
79 u8 is_atomic:1;
80
81 /* Number of gro_receive callbacks this packet already went through */
82 u8 recursion_counter:4;
83
84 /* GRO is done by frag_list pointer chaining. */
85 u8 is_flist:1;
86 );
87
88 /* used to support CHECKSUM_COMPLETE for tunneling protocols */
89 __wsum csum;
90
91 /* L3 offsets */
92 union {
93 struct {
94 u16 network_offset;
95 u16 inner_network_offset;
96 };
97 u16 network_offsets[2];
98 };
99};
100
101#define NAPI_GRO_CB(skb) ((struct napi_gro_cb *)(skb)->cb)
102
103#define GRO_RECURSION_LIMIT 15
104static inline int gro_recursion_inc_test(struct sk_buff *skb)
105{
106 return ++NAPI_GRO_CB(skb)->recursion_counter == GRO_RECURSION_LIMIT;
107}
108
109typedef struct sk_buff *(*gro_receive_t)(struct list_head *, struct sk_buff *);
110static inline struct sk_buff *call_gro_receive(gro_receive_t cb,
111 struct list_head *head,
112 struct sk_buff *skb)
113{
114 if (unlikely(gro_recursion_inc_test(skb))) {
115 NAPI_GRO_CB(skb)->flush |= 1;
116 return NULL;
117 }
118
119 return cb(head, skb);
120}
121
122typedef struct sk_buff *(*gro_receive_sk_t)(struct sock *, struct list_head *,
123 struct sk_buff *);
124static inline struct sk_buff *call_gro_receive_sk(gro_receive_sk_t cb,
125 struct sock *sk,
126 struct list_head *head,
127 struct sk_buff *skb)
128{
129 if (unlikely(gro_recursion_inc_test(skb))) {
130 NAPI_GRO_CB(skb)->flush |= 1;
131 return NULL;
132 }
133
134 return cb(sk, head, skb);
135}
136
137static inline unsigned int skb_gro_offset(const struct sk_buff *skb)
138{
139 return NAPI_GRO_CB(skb)->data_offset;
140}
141
142static inline unsigned int skb_gro_len(const struct sk_buff *skb)
143{
144 return skb->len - NAPI_GRO_CB(skb)->data_offset;
145}
146
147static inline void skb_gro_pull(struct sk_buff *skb, unsigned int len)
148{
149 NAPI_GRO_CB(skb)->data_offset += len;
150}
151
152static inline void *skb_gro_header_fast(const struct sk_buff *skb,
153 unsigned int offset)
154{
155 return NAPI_GRO_CB(skb)->frag0 + offset;
156}
157
158static inline bool skb_gro_may_pull(const struct sk_buff *skb,
159 unsigned int hlen)
160{
161 return likely(hlen <= NAPI_GRO_CB(skb)->frag0_len);
162}
163
164static inline void *skb_gro_header_slow(struct sk_buff *skb, unsigned int hlen,
165 unsigned int offset)
166{
167 if (!pskb_may_pull(skb, hlen))
168 return NULL;
169
170 return skb->data + offset;
171}
172
173static inline void *skb_gro_header(struct sk_buff *skb, unsigned int hlen,
174 unsigned int offset)
175{
176 void *ptr;
177
178 ptr = skb_gro_header_fast(skb, offset);
179 if (!skb_gro_may_pull(skb, hlen))
180 ptr = skb_gro_header_slow(skb, hlen, offset);
181 return ptr;
182}
183
184static inline void *skb_gro_network_header(const struct sk_buff *skb)
185{
186 if (skb_gro_may_pull(skb, skb_gro_offset(skb)))
187 return skb_gro_header_fast(skb, skb_network_offset(skb));
188
189 return skb_network_header(skb);
190}
191
192static inline __wsum inet_gro_compute_pseudo(const struct sk_buff *skb,
193 int proto)
194{
195 const struct iphdr *iph = skb_gro_network_header(skb);
196
197 return csum_tcpudp_nofold(iph->saddr, iph->daddr,
198 skb_gro_len(skb), proto, 0);
199}
200
201static inline void skb_gro_postpull_rcsum(struct sk_buff *skb,
202 const void *start, unsigned int len)
203{
204 if (NAPI_GRO_CB(skb)->csum_valid)
205 NAPI_GRO_CB(skb)->csum = wsum_negate(csum_partial(start, len,
206 wsum_negate(NAPI_GRO_CB(skb)->csum)));
207}
208
209/* GRO checksum functions. These are logical equivalents of the normal
210 * checksum functions (in skbuff.h) except that they operate on the GRO
211 * offsets and fields in sk_buff.
212 */
213
214__sum16 __skb_gro_checksum_complete(struct sk_buff *skb);
215
216static inline bool skb_at_gro_remcsum_start(struct sk_buff *skb)
217{
218 return (NAPI_GRO_CB(skb)->gro_remcsum_start == skb_gro_offset(skb));
219}
220
221static inline bool __skb_gro_checksum_validate_needed(struct sk_buff *skb,
222 bool zero_okay,
223 __sum16 check)
224{
225 return ((skb->ip_summed != CHECKSUM_PARTIAL ||
226 skb_checksum_start_offset(skb) <
227 skb_gro_offset(skb)) &&
228 !skb_at_gro_remcsum_start(skb) &&
229 NAPI_GRO_CB(skb)->csum_cnt == 0 &&
230 (!zero_okay || check));
231}
232
233static inline __sum16 __skb_gro_checksum_validate_complete(struct sk_buff *skb,
234 __wsum psum)
235{
236 if (NAPI_GRO_CB(skb)->csum_valid &&
237 !csum_fold(csum_add(psum, NAPI_GRO_CB(skb)->csum)))
238 return 0;
239
240 NAPI_GRO_CB(skb)->csum = psum;
241
242 return __skb_gro_checksum_complete(skb);
243}
244
245static inline void skb_gro_incr_csum_unnecessary(struct sk_buff *skb)
246{
247 if (NAPI_GRO_CB(skb)->csum_cnt > 0) {
248 /* Consume a checksum from CHECKSUM_UNNECESSARY */
249 NAPI_GRO_CB(skb)->csum_cnt--;
250 } else {
251 /* Update skb for CHECKSUM_UNNECESSARY and csum_level when we
252 * verified a new top level checksum or an encapsulated one
253 * during GRO. This saves work if we fallback to normal path.
254 */
255 __skb_incr_checksum_unnecessary(skb);
256 }
257}
258
259#define __skb_gro_checksum_validate(skb, proto, zero_okay, check, \
260 compute_pseudo) \
261({ \
262 __sum16 __ret = 0; \
263 if (__skb_gro_checksum_validate_needed(skb, zero_okay, check)) \
264 __ret = __skb_gro_checksum_validate_complete(skb, \
265 compute_pseudo(skb, proto)); \
266 if (!__ret) \
267 skb_gro_incr_csum_unnecessary(skb); \
268 __ret; \
269})
270
271#define skb_gro_checksum_validate(skb, proto, compute_pseudo) \
272 __skb_gro_checksum_validate(skb, proto, false, 0, compute_pseudo)
273
274#define skb_gro_checksum_validate_zero_check(skb, proto, check, \
275 compute_pseudo) \
276 __skb_gro_checksum_validate(skb, proto, true, check, compute_pseudo)
277
278#define skb_gro_checksum_simple_validate(skb) \
279 __skb_gro_checksum_validate(skb, 0, false, 0, null_compute_pseudo)
280
281static inline bool __skb_gro_checksum_convert_check(struct sk_buff *skb)
282{
283 return (NAPI_GRO_CB(skb)->csum_cnt == 0 &&
284 !NAPI_GRO_CB(skb)->csum_valid);
285}
286
287static inline void __skb_gro_checksum_convert(struct sk_buff *skb,
288 __wsum pseudo)
289{
290 NAPI_GRO_CB(skb)->csum = ~pseudo;
291 NAPI_GRO_CB(skb)->csum_valid = 1;
292}
293
294#define skb_gro_checksum_try_convert(skb, proto, compute_pseudo) \
295do { \
296 if (__skb_gro_checksum_convert_check(skb)) \
297 __skb_gro_checksum_convert(skb, \
298 compute_pseudo(skb, proto)); \
299} while (0)
300
301struct gro_remcsum {
302 int offset;
303 __wsum delta;
304};
305
306static inline void skb_gro_remcsum_init(struct gro_remcsum *grc)
307{
308 grc->offset = 0;
309 grc->delta = 0;
310}
311
312static inline void *skb_gro_remcsum_process(struct sk_buff *skb, void *ptr,
313 unsigned int off, size_t hdrlen,
314 int start, int offset,
315 struct gro_remcsum *grc,
316 bool nopartial)
317{
318 __wsum delta;
319 size_t plen = hdrlen + max_t(size_t, offset + sizeof(u16), start);
320
321 BUG_ON(!NAPI_GRO_CB(skb)->csum_valid);
322
323 if (!nopartial) {
324 NAPI_GRO_CB(skb)->gro_remcsum_start = off + hdrlen + start;
325 return ptr;
326 }
327
328 ptr = skb_gro_header(skb, off + plen, off);
329 if (!ptr)
330 return NULL;
331
332 delta = remcsum_adjust(ptr + hdrlen, NAPI_GRO_CB(skb)->csum,
333 start, offset);
334
335 /* Adjust skb->csum since we changed the packet */
336 NAPI_GRO_CB(skb)->csum = csum_add(NAPI_GRO_CB(skb)->csum, delta);
337
338 grc->offset = off + hdrlen + offset;
339 grc->delta = delta;
340
341 return ptr;
342}
343
344static inline void skb_gro_remcsum_cleanup(struct sk_buff *skb,
345 struct gro_remcsum *grc)
346{
347 void *ptr;
348 size_t plen = grc->offset + sizeof(u16);
349
350 if (!grc->delta)
351 return;
352
353 ptr = skb_gro_header(skb, plen, grc->offset);
354 if (!ptr)
355 return;
356
357 remcsum_unadjust((__sum16 *)ptr, grc->delta);
358}
359
360#ifdef CONFIG_XFRM_OFFLOAD
361static inline void skb_gro_flush_final(struct sk_buff *skb, struct sk_buff *pp, int flush)
362{
363 if (PTR_ERR(pp) != -EINPROGRESS)
364 NAPI_GRO_CB(skb)->flush |= flush;
365}
366static inline void skb_gro_flush_final_remcsum(struct sk_buff *skb,
367 struct sk_buff *pp,
368 int flush,
369 struct gro_remcsum *grc)
370{
371 if (PTR_ERR(pp) != -EINPROGRESS) {
372 NAPI_GRO_CB(skb)->flush |= flush;
373 skb_gro_remcsum_cleanup(skb, grc);
374 skb->remcsum_offload = 0;
375 }
376}
377#else
378static inline void skb_gro_flush_final(struct sk_buff *skb, struct sk_buff *pp, int flush)
379{
380 NAPI_GRO_CB(skb)->flush |= flush;
381}
382static inline void skb_gro_flush_final_remcsum(struct sk_buff *skb,
383 struct sk_buff *pp,
384 int flush,
385 struct gro_remcsum *grc)
386{
387 NAPI_GRO_CB(skb)->flush |= flush;
388 skb_gro_remcsum_cleanup(skb, grc);
389 skb->remcsum_offload = 0;
390}
391#endif
392
393INDIRECT_CALLABLE_DECLARE(struct sk_buff *ipv6_gro_receive(struct list_head *,
394 struct sk_buff *));
395INDIRECT_CALLABLE_DECLARE(int ipv6_gro_complete(struct sk_buff *, int));
396INDIRECT_CALLABLE_DECLARE(struct sk_buff *inet_gro_receive(struct list_head *,
397 struct sk_buff *));
398INDIRECT_CALLABLE_DECLARE(int inet_gro_complete(struct sk_buff *, int));
399
400INDIRECT_CALLABLE_DECLARE(struct sk_buff *udp4_gro_receive(struct list_head *,
401 struct sk_buff *));
402INDIRECT_CALLABLE_DECLARE(int udp4_gro_complete(struct sk_buff *, int));
403
404INDIRECT_CALLABLE_DECLARE(struct sk_buff *udp6_gro_receive(struct list_head *,
405 struct sk_buff *));
406INDIRECT_CALLABLE_DECLARE(int udp6_gro_complete(struct sk_buff *, int));
407
408#define indirect_call_gro_receive_inet(cb, f2, f1, head, skb) \
409({ \
410 unlikely(gro_recursion_inc_test(skb)) ? \
411 NAPI_GRO_CB(skb)->flush |= 1, NULL : \
412 INDIRECT_CALL_INET(cb, f2, f1, head, skb); \
413})
414
415struct sk_buff *udp_gro_receive(struct list_head *head, struct sk_buff *skb,
416 struct udphdr *uh, struct sock *sk);
417int udp_gro_complete(struct sk_buff *skb, int nhoff, udp_lookup_t lookup);
418
419static inline struct udphdr *udp_gro_udphdr(struct sk_buff *skb)
420{
421 struct udphdr *uh;
422 unsigned int hlen, off;
423
424 off = skb_gro_offset(skb);
425 hlen = off + sizeof(*uh);
426 uh = skb_gro_header(skb, hlen, off);
427
428 return uh;
429}
430
431static inline __wsum ip6_gro_compute_pseudo(const struct sk_buff *skb,
432 int proto)
433{
434 const struct ipv6hdr *iph = skb_gro_network_header(skb);
435
436 return ~csum_unfold(csum_ipv6_magic(&iph->saddr, &iph->daddr,
437 skb_gro_len(skb), proto, 0));
438}
439
440int skb_gro_receive(struct sk_buff *p, struct sk_buff *skb);
441
442/* Pass the currently batched GRO_NORMAL SKBs up to the stack. */
443static inline void gro_normal_list(struct napi_struct *napi)
444{
445 if (!napi->rx_count)
446 return;
447 netif_receive_skb_list_internal(&napi->rx_list);
448 INIT_LIST_HEAD(&napi->rx_list);
449 napi->rx_count = 0;
450}
451
452/* Queue one GRO_NORMAL SKB up for list processing. If batch size exceeded,
453 * pass the whole batch up to the stack.
454 */
455static inline void gro_normal_one(struct napi_struct *napi, struct sk_buff *skb, int segs)
456{
457 list_add_tail(&skb->list, &napi->rx_list);
458 napi->rx_count += segs;
459 if (napi->rx_count >= READ_ONCE(net_hotdata.gro_normal_batch))
460 gro_normal_list(napi);
461}
462
463/* This function is the alternative of 'inet_iif' and 'inet_sdif'
464 * functions in case we can not rely on fields of IPCB.
465 *
466 * The caller must verify skb_valid_dst(skb) is false and skb->dev is initialized.
467 * The caller must hold the RCU read lock.
468 */
469static inline void inet_get_iif_sdif(const struct sk_buff *skb, int *iif, int *sdif)
470{
471 *iif = inet_iif(skb) ?: skb->dev->ifindex;
472 *sdif = 0;
473
474#if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
475 if (netif_is_l3_slave(skb->dev)) {
476 struct net_device *master = netdev_master_upper_dev_get_rcu(skb->dev);
477
478 *sdif = *iif;
479 *iif = master ? master->ifindex : 0;
480 }
481#endif
482}
483
484/* This function is the alternative of 'inet6_iif' and 'inet6_sdif'
485 * functions in case we can not rely on fields of IP6CB.
486 *
487 * The caller must verify skb_valid_dst(skb) is false and skb->dev is initialized.
488 * The caller must hold the RCU read lock.
489 */
490static inline void inet6_get_iif_sdif(const struct sk_buff *skb, int *iif, int *sdif)
491{
492 /* using skb->dev->ifindex because skb_dst(skb) is not initialized */
493 *iif = skb->dev->ifindex;
494 *sdif = 0;
495
496#if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
497 if (netif_is_l3_slave(skb->dev)) {
498 struct net_device *master = netdev_master_upper_dev_get_rcu(skb->dev);
499
500 *sdif = *iif;
501 *iif = master ? master->ifindex : 0;
502 }
503#endif
504}
505
506struct packet_offload *gro_find_receive_by_type(__be16 type);
507struct packet_offload *gro_find_complete_by_type(__be16 type);
508
509#endif /* _NET_GRO_H */