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v6.13.7
  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
 14/* This should be increased if a protocol with a bigger head is added. */
 15#define GRO_MAX_HEAD (MAX_HEADER + 128)
 16
 17struct napi_gro_cb {
 18	union {
 19		struct {
 20			/* Virtual address of skb_shinfo(skb)->frags[0].page + offset. */
 21			void	*frag0;
 22
 23			/* Length of frag0. */
 24			unsigned int frag0_len;
 25		};
 26
 27		struct {
 28			/* used in skb_gro_receive() slow path */
 29			struct sk_buff *last;
 30
 31			/* jiffies when first packet was created/queued */
 32			unsigned long age;
 33		};
 34	};
 35
 36	/* This indicates where we are processing relative to skb->data. */
 37	int	data_offset;
 38
 39	/* This is non-zero if the packet cannot be merged with the new skb. */
 40	u16	flush;
 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	u16	pad;
 
 49
 50/* Used in napi_gro_cb::free */
 51#define NAPI_GRO_FREE             1
 52#define NAPI_GRO_FREE_STOLEN_HEAD 2
 53	/* portion of the cb set to zero at every gro iteration */
 54	struct_group(zeroed,
 55
 56		/* Start offset for remote checksum offload */
 57		u16	gro_remcsum_start;
 58
 59		/* This is non-zero if the packet may be of the same flow. */
 60		u8	same_flow:1;
 61
 62		/* Used in tunnel GRO receive */
 63		u8	encap_mark:1;
 64
 65		/* GRO checksum is valid */
 66		u8	csum_valid:1;
 67
 68		/* Number of checksums via CHECKSUM_UNNECESSARY */
 69		u8	csum_cnt:3;
 70
 71		/* Free the skb? */
 72		u8	free:2;
 73
 74		/* Used in foo-over-udp, set in udp[46]_gro_receive */
 75		u8	is_ipv6:1;
 76
 77		/* Used in GRE, set in fou/gue_gro_receive */
 78		u8	is_fou:1;
 79
 80		/* Used to determine if ipid_offset can be ignored */
 81		u8	ip_fixedid:1;
 82
 83		/* Number of gro_receive callbacks this packet already went through */
 84		u8 recursion_counter:4;
 85
 86		/* GRO is done by frag_list pointer chaining. */
 87		u8	is_flist:1;
 88	);
 89
 90	/* used to support CHECKSUM_COMPLETE for tunneling protocols */
 91	__wsum	csum;
 92
 93	/* L3 offsets */
 94	union {
 95		struct {
 96			u16 network_offset;
 97			u16 inner_network_offset;
 98		};
 99		u16 network_offsets[2];
100	};
101};
102
103#define NAPI_GRO_CB(skb) ((struct napi_gro_cb *)(skb)->cb)
104
105#define GRO_RECURSION_LIMIT 15
106static inline int gro_recursion_inc_test(struct sk_buff *skb)
107{
108	return ++NAPI_GRO_CB(skb)->recursion_counter == GRO_RECURSION_LIMIT;
109}
110
111typedef struct sk_buff *(*gro_receive_t)(struct list_head *, struct sk_buff *);
112static inline struct sk_buff *call_gro_receive(gro_receive_t cb,
113					       struct list_head *head,
114					       struct sk_buff *skb)
115{
116	if (unlikely(gro_recursion_inc_test(skb))) {
117		NAPI_GRO_CB(skb)->flush |= 1;
118		return NULL;
119	}
120
121	return cb(head, skb);
122}
123
124typedef struct sk_buff *(*gro_receive_sk_t)(struct sock *, struct list_head *,
125					    struct sk_buff *);
126static inline struct sk_buff *call_gro_receive_sk(gro_receive_sk_t cb,
127						  struct sock *sk,
128						  struct list_head *head,
129						  struct sk_buff *skb)
130{
131	if (unlikely(gro_recursion_inc_test(skb))) {
132		NAPI_GRO_CB(skb)->flush |= 1;
133		return NULL;
134	}
135
136	return cb(sk, head, skb);
137}
138
139static inline unsigned int skb_gro_offset(const struct sk_buff *skb)
140{
141	return NAPI_GRO_CB(skb)->data_offset;
142}
143
144static inline unsigned int skb_gro_len(const struct sk_buff *skb)
145{
146	return skb->len - NAPI_GRO_CB(skb)->data_offset;
147}
148
149static inline void skb_gro_pull(struct sk_buff *skb, unsigned int len)
150{
151	NAPI_GRO_CB(skb)->data_offset += len;
152}
153
154static inline void *skb_gro_header_fast(const struct sk_buff *skb,
155					unsigned int offset)
156{
157	return NAPI_GRO_CB(skb)->frag0 + offset;
158}
159
160static inline bool skb_gro_may_pull(const struct sk_buff *skb,
161				    unsigned int hlen)
 
 
 
 
162{
163	return likely(hlen <= NAPI_GRO_CB(skb)->frag0_len);
 
164}
165
166static inline void *skb_gro_header_slow(struct sk_buff *skb, unsigned int hlen,
167					unsigned int offset)
168{
169	if (!pskb_may_pull(skb, hlen))
170		return NULL;
171
 
172	return skb->data + offset;
173}
174
175static inline void *skb_gro_header(struct sk_buff *skb, unsigned int hlen,
176				   unsigned int offset)
177{
178	void *ptr;
179
180	ptr = skb_gro_header_fast(skb, offset);
181	if (!skb_gro_may_pull(skb, hlen))
182		ptr = skb_gro_header_slow(skb, hlen, offset);
183	return ptr;
184}
185
186static inline int skb_gro_receive_network_offset(const struct sk_buff *skb)
187{
188	return NAPI_GRO_CB(skb)->network_offsets[NAPI_GRO_CB(skb)->encap_mark];
 
189}
190
191static inline void *skb_gro_network_header(const struct sk_buff *skb)
192{
193	if (skb_gro_may_pull(skb, skb_gro_offset(skb)))
194		return skb_gro_header_fast(skb, skb_gro_receive_network_offset(skb));
195
196	return skb->data + skb_gro_receive_network_offset(skb);
197}
198
199static inline __wsum inet_gro_compute_pseudo(const struct sk_buff *skb,
200					     int proto)
201{
202	const struct iphdr *iph = skb_gro_network_header(skb);
203
204	return csum_tcpudp_nofold(iph->saddr, iph->daddr,
205				  skb_gro_len(skb), proto, 0);
206}
207
208static inline void skb_gro_postpull_rcsum(struct sk_buff *skb,
209					const void *start, unsigned int len)
210{
211	if (NAPI_GRO_CB(skb)->csum_valid)
212		NAPI_GRO_CB(skb)->csum = wsum_negate(csum_partial(start, len,
213						wsum_negate(NAPI_GRO_CB(skb)->csum)));
214}
215
216/* GRO checksum functions. These are logical equivalents of the normal
217 * checksum functions (in skbuff.h) except that they operate on the GRO
218 * offsets and fields in sk_buff.
219 */
220
221__sum16 __skb_gro_checksum_complete(struct sk_buff *skb);
222
223static inline bool skb_at_gro_remcsum_start(struct sk_buff *skb)
224{
225	return (NAPI_GRO_CB(skb)->gro_remcsum_start == skb_gro_offset(skb));
226}
227
228static inline bool __skb_gro_checksum_validate_needed(struct sk_buff *skb,
229						      bool zero_okay,
230						      __sum16 check)
231{
232	return ((skb->ip_summed != CHECKSUM_PARTIAL ||
233		skb_checksum_start_offset(skb) <
234		 skb_gro_offset(skb)) &&
235		!skb_at_gro_remcsum_start(skb) &&
236		NAPI_GRO_CB(skb)->csum_cnt == 0 &&
237		(!zero_okay || check));
238}
239
240static inline __sum16 __skb_gro_checksum_validate_complete(struct sk_buff *skb,
241							   __wsum psum)
242{
243	if (NAPI_GRO_CB(skb)->csum_valid &&
244	    !csum_fold(csum_add(psum, NAPI_GRO_CB(skb)->csum)))
245		return 0;
246
247	NAPI_GRO_CB(skb)->csum = psum;
248
249	return __skb_gro_checksum_complete(skb);
250}
251
252static inline void skb_gro_incr_csum_unnecessary(struct sk_buff *skb)
253{
254	if (NAPI_GRO_CB(skb)->csum_cnt > 0) {
255		/* Consume a checksum from CHECKSUM_UNNECESSARY */
256		NAPI_GRO_CB(skb)->csum_cnt--;
257	} else {
258		/* Update skb for CHECKSUM_UNNECESSARY and csum_level when we
259		 * verified a new top level checksum or an encapsulated one
260		 * during GRO. This saves work if we fallback to normal path.
261		 */
262		__skb_incr_checksum_unnecessary(skb);
263	}
264}
265
266#define __skb_gro_checksum_validate(skb, proto, zero_okay, check,	\
267				    compute_pseudo)			\
268({									\
269	__sum16 __ret = 0;						\
270	if (__skb_gro_checksum_validate_needed(skb, zero_okay, check))	\
271		__ret = __skb_gro_checksum_validate_complete(skb,	\
272				compute_pseudo(skb, proto));		\
273	if (!__ret)							\
274		skb_gro_incr_csum_unnecessary(skb);			\
275	__ret;								\
276})
277
278#define skb_gro_checksum_validate(skb, proto, compute_pseudo)		\
279	__skb_gro_checksum_validate(skb, proto, false, 0, compute_pseudo)
280
281#define skb_gro_checksum_validate_zero_check(skb, proto, check,		\
282					     compute_pseudo)		\
283	__skb_gro_checksum_validate(skb, proto, true, check, compute_pseudo)
284
285#define skb_gro_checksum_simple_validate(skb)				\
286	__skb_gro_checksum_validate(skb, 0, false, 0, null_compute_pseudo)
287
288static inline bool __skb_gro_checksum_convert_check(struct sk_buff *skb)
289{
290	return (NAPI_GRO_CB(skb)->csum_cnt == 0 &&
291		!NAPI_GRO_CB(skb)->csum_valid);
292}
293
294static inline void __skb_gro_checksum_convert(struct sk_buff *skb,
295					      __wsum pseudo)
296{
297	NAPI_GRO_CB(skb)->csum = ~pseudo;
298	NAPI_GRO_CB(skb)->csum_valid = 1;
299}
300
301#define skb_gro_checksum_try_convert(skb, proto, compute_pseudo)	\
302do {									\
303	if (__skb_gro_checksum_convert_check(skb))			\
304		__skb_gro_checksum_convert(skb, 			\
305					   compute_pseudo(skb, proto));	\
306} while (0)
307
308struct gro_remcsum {
309	int offset;
310	__wsum delta;
311};
312
313static inline void skb_gro_remcsum_init(struct gro_remcsum *grc)
314{
315	grc->offset = 0;
316	grc->delta = 0;
317}
318
319static inline void *skb_gro_remcsum_process(struct sk_buff *skb, void *ptr,
320					    unsigned int off, size_t hdrlen,
321					    int start, int offset,
322					    struct gro_remcsum *grc,
323					    bool nopartial)
324{
325	__wsum delta;
326	size_t plen = hdrlen + max_t(size_t, offset + sizeof(u16), start);
327
328	BUG_ON(!NAPI_GRO_CB(skb)->csum_valid);
329
330	if (!nopartial) {
331		NAPI_GRO_CB(skb)->gro_remcsum_start = off + hdrlen + start;
332		return ptr;
333	}
334
335	ptr = skb_gro_header(skb, off + plen, off);
336	if (!ptr)
337		return NULL;
338
339	delta = remcsum_adjust(ptr + hdrlen, NAPI_GRO_CB(skb)->csum,
340			       start, offset);
341
342	/* Adjust skb->csum since we changed the packet */
343	NAPI_GRO_CB(skb)->csum = csum_add(NAPI_GRO_CB(skb)->csum, delta);
344
345	grc->offset = off + hdrlen + offset;
346	grc->delta = delta;
347
348	return ptr;
349}
350
351static inline void skb_gro_remcsum_cleanup(struct sk_buff *skb,
352					   struct gro_remcsum *grc)
353{
354	void *ptr;
355	size_t plen = grc->offset + sizeof(u16);
356
357	if (!grc->delta)
358		return;
359
360	ptr = skb_gro_header(skb, plen, grc->offset);
361	if (!ptr)
362		return;
363
364	remcsum_unadjust((__sum16 *)ptr, grc->delta);
365}
366
367#ifdef CONFIG_XFRM_OFFLOAD
368static inline void skb_gro_flush_final(struct sk_buff *skb, struct sk_buff *pp, int flush)
369{
370	if (PTR_ERR(pp) != -EINPROGRESS)
371		NAPI_GRO_CB(skb)->flush |= flush;
372}
373static inline void skb_gro_flush_final_remcsum(struct sk_buff *skb,
374					       struct sk_buff *pp,
375					       int flush,
376					       struct gro_remcsum *grc)
377{
378	if (PTR_ERR(pp) != -EINPROGRESS) {
379		NAPI_GRO_CB(skb)->flush |= flush;
380		skb_gro_remcsum_cleanup(skb, grc);
381		skb->remcsum_offload = 0;
382	}
383}
384#else
385static inline void skb_gro_flush_final(struct sk_buff *skb, struct sk_buff *pp, int flush)
386{
387	NAPI_GRO_CB(skb)->flush |= flush;
388}
389static inline void skb_gro_flush_final_remcsum(struct sk_buff *skb,
390					       struct sk_buff *pp,
391					       int flush,
392					       struct gro_remcsum *grc)
393{
394	NAPI_GRO_CB(skb)->flush |= flush;
395	skb_gro_remcsum_cleanup(skb, grc);
396	skb->remcsum_offload = 0;
397}
398#endif
399
400INDIRECT_CALLABLE_DECLARE(struct sk_buff *ipv6_gro_receive(struct list_head *,
401							   struct sk_buff *));
402INDIRECT_CALLABLE_DECLARE(int ipv6_gro_complete(struct sk_buff *, int));
403INDIRECT_CALLABLE_DECLARE(struct sk_buff *inet_gro_receive(struct list_head *,
404							   struct sk_buff *));
405INDIRECT_CALLABLE_DECLARE(int inet_gro_complete(struct sk_buff *, int));
406
407INDIRECT_CALLABLE_DECLARE(struct sk_buff *udp4_gro_receive(struct list_head *,
408							   struct sk_buff *));
409INDIRECT_CALLABLE_DECLARE(int udp4_gro_complete(struct sk_buff *, int));
410
411INDIRECT_CALLABLE_DECLARE(struct sk_buff *udp6_gro_receive(struct list_head *,
412							   struct sk_buff *));
413INDIRECT_CALLABLE_DECLARE(int udp6_gro_complete(struct sk_buff *, int));
414
415#define indirect_call_gro_receive_inet(cb, f2, f1, head, skb)	\
416({								\
417	unlikely(gro_recursion_inc_test(skb)) ?			\
418		NAPI_GRO_CB(skb)->flush |= 1, NULL :		\
419		INDIRECT_CALL_INET(cb, f2, f1, head, skb);	\
420})
421
422struct sk_buff *udp_gro_receive(struct list_head *head, struct sk_buff *skb,
423				struct udphdr *uh, struct sock *sk);
424int udp_gro_complete(struct sk_buff *skb, int nhoff, udp_lookup_t lookup);
425
426static inline struct udphdr *udp_gro_udphdr(struct sk_buff *skb)
427{
428	struct udphdr *uh;
429	unsigned int hlen, off;
430
431	off  = skb_gro_offset(skb);
432	hlen = off + sizeof(*uh);
433	uh   = skb_gro_header(skb, hlen, off);
434
435	return uh;
436}
437
438static inline __wsum ip6_gro_compute_pseudo(const struct sk_buff *skb,
439					    int proto)
440{
441	const struct ipv6hdr *iph = skb_gro_network_header(skb);
442
443	return ~csum_unfold(csum_ipv6_magic(&iph->saddr, &iph->daddr,
444					    skb_gro_len(skb), proto, 0));
445}
446
447static inline int inet_gro_flush(const struct iphdr *iph, const struct iphdr *iph2,
448				 struct sk_buff *p, bool outer)
449{
450	const u32 id = ntohl(*(__be32 *)&iph->id);
451	const u32 id2 = ntohl(*(__be32 *)&iph2->id);
452	const u16 ipid_offset = (id >> 16) - (id2 >> 16);
453	const u16 count = NAPI_GRO_CB(p)->count;
454	const u32 df = id & IP_DF;
455	int flush;
456
457	/* All fields must match except length and checksum. */
458	flush = (iph->ttl ^ iph2->ttl) | (iph->tos ^ iph2->tos) | (df ^ (id2 & IP_DF));
459
460	if (flush | (outer && df))
461		return flush;
462
463	/* When we receive our second frame we can make a decision on if we
464	 * continue this flow as an atomic flow with a fixed ID or if we use
465	 * an incrementing ID.
466	 */
467	if (count == 1 && df && !ipid_offset)
468		NAPI_GRO_CB(p)->ip_fixedid = true;
469
470	return ipid_offset ^ (count * !NAPI_GRO_CB(p)->ip_fixedid);
471}
472
473static inline int ipv6_gro_flush(const struct ipv6hdr *iph, const struct ipv6hdr *iph2)
474{
475	/* <Version:4><Traffic_Class:8><Flow_Label:20> */
476	__be32 first_word = *(__be32 *)iph ^ *(__be32 *)iph2;
477
478	/* Flush if Traffic Class fields are different. */
479	return !!((first_word & htonl(0x0FF00000)) |
480		(__force __be32)(iph->hop_limit ^ iph2->hop_limit));
481}
482
483static inline int __gro_receive_network_flush(const void *th, const void *th2,
484					      struct sk_buff *p, const u16 diff,
485					      bool outer)
486{
487	const void *nh = th - diff;
488	const void *nh2 = th2 - diff;
489
490	if (((struct iphdr *)nh)->version == 6)
491		return ipv6_gro_flush(nh, nh2);
492	else
493		return inet_gro_flush(nh, nh2, p, outer);
494}
495
496static inline int gro_receive_network_flush(const void *th, const void *th2,
497					    struct sk_buff *p)
498{
499	const bool encap_mark = NAPI_GRO_CB(p)->encap_mark;
500	int off = skb_transport_offset(p);
501	int flush;
502
503	flush = __gro_receive_network_flush(th, th2, p, off - NAPI_GRO_CB(p)->network_offset, encap_mark);
504	if (encap_mark)
505		flush |= __gro_receive_network_flush(th, th2, p, off - NAPI_GRO_CB(p)->inner_network_offset, false);
506
507	return flush;
508}
509
510int skb_gro_receive(struct sk_buff *p, struct sk_buff *skb);
511int skb_gro_receive_list(struct sk_buff *p, struct sk_buff *skb);
512
513/* Pass the currently batched GRO_NORMAL SKBs up to the stack. */
514static inline void gro_normal_list(struct napi_struct *napi)
515{
516	if (!napi->rx_count)
517		return;
518	netif_receive_skb_list_internal(&napi->rx_list);
519	INIT_LIST_HEAD(&napi->rx_list);
520	napi->rx_count = 0;
521}
522
523/* Queue one GRO_NORMAL SKB up for list processing. If batch size exceeded,
524 * pass the whole batch up to the stack.
525 */
526static inline void gro_normal_one(struct napi_struct *napi, struct sk_buff *skb, int segs)
527{
528	list_add_tail(&skb->list, &napi->rx_list);
529	napi->rx_count += segs;
530	if (napi->rx_count >= READ_ONCE(net_hotdata.gro_normal_batch))
531		gro_normal_list(napi);
532}
533
534/* This function is the alternative of 'inet_iif' and 'inet_sdif'
535 * functions in case we can not rely on fields of IPCB.
536 *
537 * The caller must verify skb_valid_dst(skb) is false and skb->dev is initialized.
538 * The caller must hold the RCU read lock.
539 */
540static inline void inet_get_iif_sdif(const struct sk_buff *skb, int *iif, int *sdif)
541{
542	*iif = inet_iif(skb) ?: skb->dev->ifindex;
543	*sdif = 0;
544
545#if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
546	if (netif_is_l3_slave(skb->dev)) {
547		struct net_device *master = netdev_master_upper_dev_get_rcu(skb->dev);
548
549		*sdif = *iif;
550		*iif = master ? master->ifindex : 0;
551	}
552#endif
553}
554
555/* This function is the alternative of 'inet6_iif' and 'inet6_sdif'
556 * functions in case we can not rely on fields of IP6CB.
557 *
558 * The caller must verify skb_valid_dst(skb) is false and skb->dev is initialized.
559 * The caller must hold the RCU read lock.
560 */
561static inline void inet6_get_iif_sdif(const struct sk_buff *skb, int *iif, int *sdif)
562{
563	/* using skb->dev->ifindex because skb_dst(skb) is not initialized */
564	*iif = skb->dev->ifindex;
565	*sdif = 0;
566
567#if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
568	if (netif_is_l3_slave(skb->dev)) {
569		struct net_device *master = netdev_master_upper_dev_get_rcu(skb->dev);
570
571		*sdif = *iif;
572		*iif = master ? master->ifindex : 0;
573	}
574#endif
575}
576
577struct packet_offload *gro_find_receive_by_type(__be16 type);
578struct packet_offload *gro_find_complete_by_type(__be16 type);
579
580#endif /* _NET_GRO_H */
v6.2
  1/* SPDX-License-Identifier: GPL-2.0-or-later */
  2
  3#ifndef _NET_IPV6_GRO_H
  4#define _NET_IPV6_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
 13struct napi_gro_cb {
 14	/* Virtual address of skb_shinfo(skb)->frags[0].page + offset. */
 15	void	*frag0;
 16
 17	/* Length of frag0. */
 18	unsigned int frag0_len;
 
 
 
 
 
 
 
 
 
 
 
 
 19
 20	/* This indicates where we are processing relative to skb->data. */
 21	int	data_offset;
 22
 23	/* This is non-zero if the packet cannot be merged with the new skb. */
 24	u16	flush;
 25
 26	/* Save the IP ID here and check when we get to the transport layer */
 27	u16	flush_id;
 28
 29	/* Number of segments aggregated. */
 30	u16	count;
 31
 32	/* Used in ipv6_gro_receive() and foo-over-udp */
 33	u16	proto;
 34
 35	/* jiffies when first packet was created/queued */
 36	unsigned long age;
 37
 38/* Used in napi_gro_cb::free */
 39#define NAPI_GRO_FREE             1
 40#define NAPI_GRO_FREE_STOLEN_HEAD 2
 41	/* portion of the cb set to zero at every gro iteration */
 42	struct_group(zeroed,
 43
 44		/* Start offset for remote checksum offload */
 45		u16	gro_remcsum_start;
 46
 47		/* This is non-zero if the packet may be of the same flow. */
 48		u8	same_flow:1;
 49
 50		/* Used in tunnel GRO receive */
 51		u8	encap_mark:1;
 52
 53		/* GRO checksum is valid */
 54		u8	csum_valid:1;
 55
 56		/* Number of checksums via CHECKSUM_UNNECESSARY */
 57		u8	csum_cnt:3;
 58
 59		/* Free the skb? */
 60		u8	free:2;
 61
 62		/* Used in foo-over-udp, set in udp[46]_gro_receive */
 63		u8	is_ipv6:1;
 64
 65		/* Used in GRE, set in fou/gue_gro_receive */
 66		u8	is_fou:1;
 67
 68		/* Used to determine if flush_id can be ignored */
 69		u8	is_atomic:1;
 70
 71		/* Number of gro_receive callbacks this packet already went through */
 72		u8 recursion_counter:4;
 73
 74		/* GRO is done by frag_list pointer chaining. */
 75		u8	is_flist:1;
 76	);
 77
 78	/* used to support CHECKSUM_COMPLETE for tunneling protocols */
 79	__wsum	csum;
 80
 81	/* used in skb_gro_receive() slow path */
 82	struct sk_buff *last;
 
 
 
 
 
 
 83};
 84
 85#define NAPI_GRO_CB(skb) ((struct napi_gro_cb *)(skb)->cb)
 86
 87#define GRO_RECURSION_LIMIT 15
 88static inline int gro_recursion_inc_test(struct sk_buff *skb)
 89{
 90	return ++NAPI_GRO_CB(skb)->recursion_counter == GRO_RECURSION_LIMIT;
 91}
 92
 93typedef struct sk_buff *(*gro_receive_t)(struct list_head *, struct sk_buff *);
 94static inline struct sk_buff *call_gro_receive(gro_receive_t cb,
 95					       struct list_head *head,
 96					       struct sk_buff *skb)
 97{
 98	if (unlikely(gro_recursion_inc_test(skb))) {
 99		NAPI_GRO_CB(skb)->flush |= 1;
100		return NULL;
101	}
102
103	return cb(head, skb);
104}
105
106typedef struct sk_buff *(*gro_receive_sk_t)(struct sock *, struct list_head *,
107					    struct sk_buff *);
108static inline struct sk_buff *call_gro_receive_sk(gro_receive_sk_t cb,
109						  struct sock *sk,
110						  struct list_head *head,
111						  struct sk_buff *skb)
112{
113	if (unlikely(gro_recursion_inc_test(skb))) {
114		NAPI_GRO_CB(skb)->flush |= 1;
115		return NULL;
116	}
117
118	return cb(sk, head, skb);
119}
120
121static inline unsigned int skb_gro_offset(const struct sk_buff *skb)
122{
123	return NAPI_GRO_CB(skb)->data_offset;
124}
125
126static inline unsigned int skb_gro_len(const struct sk_buff *skb)
127{
128	return skb->len - NAPI_GRO_CB(skb)->data_offset;
129}
130
131static inline void skb_gro_pull(struct sk_buff *skb, unsigned int len)
132{
133	NAPI_GRO_CB(skb)->data_offset += len;
134}
135
136static inline void *skb_gro_header_fast(struct sk_buff *skb,
137					unsigned int offset)
138{
139	return NAPI_GRO_CB(skb)->frag0 + offset;
140}
141
142static inline int skb_gro_header_hard(struct sk_buff *skb, unsigned int hlen)
143{
144	return NAPI_GRO_CB(skb)->frag0_len < hlen;
145}
146
147static inline void skb_gro_frag0_invalidate(struct sk_buff *skb)
148{
149	NAPI_GRO_CB(skb)->frag0 = NULL;
150	NAPI_GRO_CB(skb)->frag0_len = 0;
151}
152
153static inline void *skb_gro_header_slow(struct sk_buff *skb, unsigned int hlen,
154					unsigned int offset)
155{
156	if (!pskb_may_pull(skb, hlen))
157		return NULL;
158
159	skb_gro_frag0_invalidate(skb);
160	return skb->data + offset;
161}
162
163static inline void *skb_gro_header(struct sk_buff *skb,
164					unsigned int hlen, unsigned int offset)
165{
166	void *ptr;
167
168	ptr = skb_gro_header_fast(skb, offset);
169	if (skb_gro_header_hard(skb, hlen))
170		ptr = skb_gro_header_slow(skb, hlen, offset);
171	return ptr;
172}
173
174static inline void *skb_gro_network_header(struct sk_buff *skb)
175{
176	return (NAPI_GRO_CB(skb)->frag0 ?: skb->data) +
177	       skb_network_offset(skb);
178}
179
180static inline __wsum inet_gro_compute_pseudo(struct sk_buff *skb, int proto)
 
 
 
 
 
 
 
 
 
181{
182	const struct iphdr *iph = skb_gro_network_header(skb);
183
184	return csum_tcpudp_nofold(iph->saddr, iph->daddr,
185				  skb_gro_len(skb), proto, 0);
186}
187
188static inline void skb_gro_postpull_rcsum(struct sk_buff *skb,
189					const void *start, unsigned int len)
190{
191	if (NAPI_GRO_CB(skb)->csum_valid)
192		NAPI_GRO_CB(skb)->csum = wsum_negate(csum_partial(start, len,
193						wsum_negate(NAPI_GRO_CB(skb)->csum)));
194}
195
196/* GRO checksum functions. These are logical equivalents of the normal
197 * checksum functions (in skbuff.h) except that they operate on the GRO
198 * offsets and fields in sk_buff.
199 */
200
201__sum16 __skb_gro_checksum_complete(struct sk_buff *skb);
202
203static inline bool skb_at_gro_remcsum_start(struct sk_buff *skb)
204{
205	return (NAPI_GRO_CB(skb)->gro_remcsum_start == skb_gro_offset(skb));
206}
207
208static inline bool __skb_gro_checksum_validate_needed(struct sk_buff *skb,
209						      bool zero_okay,
210						      __sum16 check)
211{
212	return ((skb->ip_summed != CHECKSUM_PARTIAL ||
213		skb_checksum_start_offset(skb) <
214		 skb_gro_offset(skb)) &&
215		!skb_at_gro_remcsum_start(skb) &&
216		NAPI_GRO_CB(skb)->csum_cnt == 0 &&
217		(!zero_okay || check));
218}
219
220static inline __sum16 __skb_gro_checksum_validate_complete(struct sk_buff *skb,
221							   __wsum psum)
222{
223	if (NAPI_GRO_CB(skb)->csum_valid &&
224	    !csum_fold(csum_add(psum, NAPI_GRO_CB(skb)->csum)))
225		return 0;
226
227	NAPI_GRO_CB(skb)->csum = psum;
228
229	return __skb_gro_checksum_complete(skb);
230}
231
232static inline void skb_gro_incr_csum_unnecessary(struct sk_buff *skb)
233{
234	if (NAPI_GRO_CB(skb)->csum_cnt > 0) {
235		/* Consume a checksum from CHECKSUM_UNNECESSARY */
236		NAPI_GRO_CB(skb)->csum_cnt--;
237	} else {
238		/* Update skb for CHECKSUM_UNNECESSARY and csum_level when we
239		 * verified a new top level checksum or an encapsulated one
240		 * during GRO. This saves work if we fallback to normal path.
241		 */
242		__skb_incr_checksum_unnecessary(skb);
243	}
244}
245
246#define __skb_gro_checksum_validate(skb, proto, zero_okay, check,	\
247				    compute_pseudo)			\
248({									\
249	__sum16 __ret = 0;						\
250	if (__skb_gro_checksum_validate_needed(skb, zero_okay, check))	\
251		__ret = __skb_gro_checksum_validate_complete(skb,	\
252				compute_pseudo(skb, proto));		\
253	if (!__ret)							\
254		skb_gro_incr_csum_unnecessary(skb);			\
255	__ret;								\
256})
257
258#define skb_gro_checksum_validate(skb, proto, compute_pseudo)		\
259	__skb_gro_checksum_validate(skb, proto, false, 0, compute_pseudo)
260
261#define skb_gro_checksum_validate_zero_check(skb, proto, check,		\
262					     compute_pseudo)		\
263	__skb_gro_checksum_validate(skb, proto, true, check, compute_pseudo)
264
265#define skb_gro_checksum_simple_validate(skb)				\
266	__skb_gro_checksum_validate(skb, 0, false, 0, null_compute_pseudo)
267
268static inline bool __skb_gro_checksum_convert_check(struct sk_buff *skb)
269{
270	return (NAPI_GRO_CB(skb)->csum_cnt == 0 &&
271		!NAPI_GRO_CB(skb)->csum_valid);
272}
273
274static inline void __skb_gro_checksum_convert(struct sk_buff *skb,
275					      __wsum pseudo)
276{
277	NAPI_GRO_CB(skb)->csum = ~pseudo;
278	NAPI_GRO_CB(skb)->csum_valid = 1;
279}
280
281#define skb_gro_checksum_try_convert(skb, proto, compute_pseudo)	\
282do {									\
283	if (__skb_gro_checksum_convert_check(skb))			\
284		__skb_gro_checksum_convert(skb, 			\
285					   compute_pseudo(skb, proto));	\
286} while (0)
287
288struct gro_remcsum {
289	int offset;
290	__wsum delta;
291};
292
293static inline void skb_gro_remcsum_init(struct gro_remcsum *grc)
294{
295	grc->offset = 0;
296	grc->delta = 0;
297}
298
299static inline void *skb_gro_remcsum_process(struct sk_buff *skb, void *ptr,
300					    unsigned int off, size_t hdrlen,
301					    int start, int offset,
302					    struct gro_remcsum *grc,
303					    bool nopartial)
304{
305	__wsum delta;
306	size_t plen = hdrlen + max_t(size_t, offset + sizeof(u16), start);
307
308	BUG_ON(!NAPI_GRO_CB(skb)->csum_valid);
309
310	if (!nopartial) {
311		NAPI_GRO_CB(skb)->gro_remcsum_start = off + hdrlen + start;
312		return ptr;
313	}
314
315	ptr = skb_gro_header(skb, off + plen, off);
316	if (!ptr)
317		return NULL;
318
319	delta = remcsum_adjust(ptr + hdrlen, NAPI_GRO_CB(skb)->csum,
320			       start, offset);
321
322	/* Adjust skb->csum since we changed the packet */
323	NAPI_GRO_CB(skb)->csum = csum_add(NAPI_GRO_CB(skb)->csum, delta);
324
325	grc->offset = off + hdrlen + offset;
326	grc->delta = delta;
327
328	return ptr;
329}
330
331static inline void skb_gro_remcsum_cleanup(struct sk_buff *skb,
332					   struct gro_remcsum *grc)
333{
334	void *ptr;
335	size_t plen = grc->offset + sizeof(u16);
336
337	if (!grc->delta)
338		return;
339
340	ptr = skb_gro_header(skb, plen, grc->offset);
341	if (!ptr)
342		return;
343
344	remcsum_unadjust((__sum16 *)ptr, grc->delta);
345}
346
347#ifdef CONFIG_XFRM_OFFLOAD
348static inline void skb_gro_flush_final(struct sk_buff *skb, struct sk_buff *pp, int flush)
349{
350	if (PTR_ERR(pp) != -EINPROGRESS)
351		NAPI_GRO_CB(skb)->flush |= flush;
352}
353static inline void skb_gro_flush_final_remcsum(struct sk_buff *skb,
354					       struct sk_buff *pp,
355					       int flush,
356					       struct gro_remcsum *grc)
357{
358	if (PTR_ERR(pp) != -EINPROGRESS) {
359		NAPI_GRO_CB(skb)->flush |= flush;
360		skb_gro_remcsum_cleanup(skb, grc);
361		skb->remcsum_offload = 0;
362	}
363}
364#else
365static inline void skb_gro_flush_final(struct sk_buff *skb, struct sk_buff *pp, int flush)
366{
367	NAPI_GRO_CB(skb)->flush |= flush;
368}
369static inline void skb_gro_flush_final_remcsum(struct sk_buff *skb,
370					       struct sk_buff *pp,
371					       int flush,
372					       struct gro_remcsum *grc)
373{
374	NAPI_GRO_CB(skb)->flush |= flush;
375	skb_gro_remcsum_cleanup(skb, grc);
376	skb->remcsum_offload = 0;
377}
378#endif
379
380INDIRECT_CALLABLE_DECLARE(struct sk_buff *ipv6_gro_receive(struct list_head *,
381							   struct sk_buff *));
382INDIRECT_CALLABLE_DECLARE(int ipv6_gro_complete(struct sk_buff *, int));
383INDIRECT_CALLABLE_DECLARE(struct sk_buff *inet_gro_receive(struct list_head *,
384							   struct sk_buff *));
385INDIRECT_CALLABLE_DECLARE(int inet_gro_complete(struct sk_buff *, int));
386
387INDIRECT_CALLABLE_DECLARE(struct sk_buff *udp4_gro_receive(struct list_head *,
388							   struct sk_buff *));
389INDIRECT_CALLABLE_DECLARE(int udp4_gro_complete(struct sk_buff *, int));
390
391INDIRECT_CALLABLE_DECLARE(struct sk_buff *udp6_gro_receive(struct list_head *,
392							   struct sk_buff *));
393INDIRECT_CALLABLE_DECLARE(int udp6_gro_complete(struct sk_buff *, int));
394
395#define indirect_call_gro_receive_inet(cb, f2, f1, head, skb)	\
396({								\
397	unlikely(gro_recursion_inc_test(skb)) ?			\
398		NAPI_GRO_CB(skb)->flush |= 1, NULL :		\
399		INDIRECT_CALL_INET(cb, f2, f1, head, skb);	\
400})
401
402struct sk_buff *udp_gro_receive(struct list_head *head, struct sk_buff *skb,
403				struct udphdr *uh, struct sock *sk);
404int udp_gro_complete(struct sk_buff *skb, int nhoff, udp_lookup_t lookup);
405
406static inline struct udphdr *udp_gro_udphdr(struct sk_buff *skb)
407{
408	struct udphdr *uh;
409	unsigned int hlen, off;
410
411	off  = skb_gro_offset(skb);
412	hlen = off + sizeof(*uh);
413	uh   = skb_gro_header(skb, hlen, off);
414
415	return uh;
416}
417
418static inline __wsum ip6_gro_compute_pseudo(struct sk_buff *skb, int proto)
 
419{
420	const struct ipv6hdr *iph = skb_gro_network_header(skb);
421
422	return ~csum_unfold(csum_ipv6_magic(&iph->saddr, &iph->daddr,
423					    skb_gro_len(skb), proto, 0));
424}
425
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
426int skb_gro_receive(struct sk_buff *p, struct sk_buff *skb);
 
427
428/* Pass the currently batched GRO_NORMAL SKBs up to the stack. */
429static inline void gro_normal_list(struct napi_struct *napi)
430{
431	if (!napi->rx_count)
432		return;
433	netif_receive_skb_list_internal(&napi->rx_list);
434	INIT_LIST_HEAD(&napi->rx_list);
435	napi->rx_count = 0;
436}
437
438/* Queue one GRO_NORMAL SKB up for list processing. If batch size exceeded,
439 * pass the whole batch up to the stack.
440 */
441static inline void gro_normal_one(struct napi_struct *napi, struct sk_buff *skb, int segs)
442{
443	list_add_tail(&skb->list, &napi->rx_list);
444	napi->rx_count += segs;
445	if (napi->rx_count >= READ_ONCE(gro_normal_batch))
446		gro_normal_list(napi);
447}
448
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
449
450#endif /* _NET_IPV6_GRO_H */