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/* SPDX-License-Identifier: GPL-2.0-or-later */ #ifndef _NET_GRO_H#define _NET_GRO_H #include <linux/indirect_call_wrapper.h>#include <linux/ip.h>#include <linux/ipv6.h>#include <net/ip6_checksum.h>#include <linux/skbuff.h>#include <net/udp.h>#include <net/hotdata.h> /* This should be increased if a protocol with a bigger head is added. */#define GRO_MAX_HEAD (MAX_HEADER + 128) struct napi_gro_cb {	union {		struct {			/* Virtual address of skb_shinfo(skb)->frags[0].page + offset. */			void	*frag0; 			/* Length of frag0. */			unsigned int frag0_len;		}; 		struct {			/* used in skb_gro_receive() slow path */			struct sk_buff *last; 			/* jiffies when first packet was created/queued */			unsigned long age;		};	}; 	/* This indicates where we are processing relative to skb->data. */	int	data_offset; 	/* This is non-zero if the packet cannot be merged with the new skb. */	u16	flush; 	/* Number of segments aggregated. */	u16	count; 	/* Used in ipv6_gro_receive() and foo-over-udp and esp-in-udp */	u16	proto; 	u16	pad; /* Used in napi_gro_cb::free */#define NAPI_GRO_FREE             1#define NAPI_GRO_FREE_STOLEN_HEAD 2	/* portion of the cb set to zero at every gro iteration */	struct_group(zeroed, 		/* Start offset for remote checksum offload */		u16	gro_remcsum_start; 		/* This is non-zero if the packet may be of the same flow. */		u8	same_flow:1; 		/* Used in tunnel GRO receive */		u8	encap_mark:1; 		/* GRO checksum is valid */		u8	csum_valid:1; 		/* Number of checksums via CHECKSUM_UNNECESSARY */		u8	csum_cnt:3; 		/* Free the skb? */		u8	free:2; 		/* Used in GRE, set in fou/gue_gro_receive */		u8	is_fou:1; 		/* Used to determine if ipid_offset can be ignored */		u8	ip_fixedid:2; 		/* Number of gro_receive callbacks this packet already went through */		u8 recursion_counter:4; 		/* GRO is done by frag_list pointer chaining. */		u8	is_flist:1;	); 	/* used to support CHECKSUM_COMPLETE for tunneling protocols */	__wsum	csum; 	/* L3 offsets */	union {		struct {			u16 network_offset;			u16 inner_network_offset;		};		u16 network_offsets[2];	};}; #define NAPI_GRO_CB(skb) ((struct napi_gro_cb *)(skb)->cb) #define GRO_RECURSION_LIMIT 15static inline int gro_recursion_inc_test(struct sk_buff *skb){	return ++NAPI_GRO_CB(skb)->recursion_counter == GRO_RECURSION_LIMIT;} typedef struct sk_buff *(*gro_receive_t)(struct list_head *, struct sk_buff *);static inline struct sk_buff *call_gro_receive(gro_receive_t cb,					       struct list_head *head,					       struct sk_buff *skb){	if (unlikely(gro_recursion_inc_test(skb))) {		NAPI_GRO_CB(skb)->flush |= 1;		return NULL;	} 	return cb(head, skb);} typedef struct sk_buff *(*gro_receive_sk_t)(struct sock *, struct list_head *,					    struct sk_buff *);static inline struct sk_buff *call_gro_receive_sk(gro_receive_sk_t cb,						  struct sock *sk,						  struct list_head *head,						  struct sk_buff *skb){	if (unlikely(gro_recursion_inc_test(skb))) {		NAPI_GRO_CB(skb)->flush |= 1;		return NULL;	} 	return cb(sk, head, skb);} static inline unsigned int skb_gro_offset(const struct sk_buff *skb){	return NAPI_GRO_CB(skb)->data_offset;} static inline unsigned int skb_gro_len(const struct sk_buff *skb){	return skb->len - NAPI_GRO_CB(skb)->data_offset;} static inline void skb_gro_pull(struct sk_buff *skb, unsigned int len){	NAPI_GRO_CB(skb)->data_offset += len;} static inline void *skb_gro_header_fast(const struct sk_buff *skb,					unsigned int offset){	return NAPI_GRO_CB(skb)->frag0 + offset;} static inline bool skb_gro_may_pull(const struct sk_buff *skb,				    unsigned int hlen){	return likely(hlen <= NAPI_GRO_CB(skb)->frag0_len);} static inline void *skb_gro_header_slow(struct sk_buff *skb, unsigned int hlen,					unsigned int offset){	if (!pskb_may_pull(skb, hlen))		return NULL; 	return skb->data + offset;} static inline void *skb_gro_header(struct sk_buff *skb, unsigned int hlen,				   unsigned int offset){	void *ptr; 	ptr = skb_gro_header_fast(skb, offset);	if (!skb_gro_may_pull(skb, hlen))		ptr = skb_gro_header_slow(skb, hlen, offset);	return ptr;} static inline int skb_gro_receive_network_offset(const struct sk_buff *skb){	return NAPI_GRO_CB(skb)->network_offsets[NAPI_GRO_CB(skb)->encap_mark];} static inline void *skb_gro_network_header(const struct sk_buff *skb){	if (skb_gro_may_pull(skb, skb_gro_offset(skb)))		return skb_gro_header_fast(skb, skb_gro_receive_network_offset(skb)); 	return skb->data + skb_gro_receive_network_offset(skb);} static inline __wsum inet_gro_compute_pseudo(const struct sk_buff *skb,					     int proto){	const struct iphdr *iph = skb_gro_network_header(skb); 	return csum_tcpudp_nofold(iph->saddr, iph->daddr,				  skb_gro_len(skb), proto, 0);} static inline void skb_gro_postpull_rcsum(struct sk_buff *skb,					const void *start, unsigned int len){	if (NAPI_GRO_CB(skb)->csum_valid)		NAPI_GRO_CB(skb)->csum = wsum_negate(csum_partial(start, len,						wsum_negate(NAPI_GRO_CB(skb)->csum)));} /* GRO checksum functions. These are logical equivalents of the normal * checksum functions (in skbuff.h) except that they operate on the GRO * offsets and fields in sk_buff. */ __sum16 __skb_gro_checksum_complete(struct sk_buff *skb); static inline bool skb_at_gro_remcsum_start(struct sk_buff *skb){	return (NAPI_GRO_CB(skb)->gro_remcsum_start == skb_gro_offset(skb));} static inline bool __skb_gro_checksum_validate_needed(struct sk_buff *skb,						      bool zero_okay,						      __sum16 check){	return ((skb->ip_summed != CHECKSUM_PARTIAL ||		skb_checksum_start_offset(skb) <		 skb_gro_offset(skb)) &&		!skb_at_gro_remcsum_start(skb) &&		NAPI_GRO_CB(skb)->csum_cnt == 0 &&		(!zero_okay || check));} static inline __sum16 __skb_gro_checksum_validate_complete(struct sk_buff *skb,							   __wsum psum){	if (NAPI_GRO_CB(skb)->csum_valid &&	    !csum_fold(csum_add(psum, NAPI_GRO_CB(skb)->csum)))		return 0; 	NAPI_GRO_CB(skb)->csum = psum; 	return __skb_gro_checksum_complete(skb);} static inline void skb_gro_incr_csum_unnecessary(struct sk_buff *skb){	if (NAPI_GRO_CB(skb)->csum_cnt > 0) {		/* Consume a checksum from CHECKSUM_UNNECESSARY */		NAPI_GRO_CB(skb)->csum_cnt--;	} else {		/* Update skb for CHECKSUM_UNNECESSARY and csum_level when we		 * verified a new top level checksum or an encapsulated one		 * during GRO. This saves work if we fallback to normal path.		 */		__skb_incr_checksum_unnecessary(skb);	}} #define __skb_gro_checksum_validate(skb, proto, zero_okay, check,	\				    compute_pseudo)			\({									\	__sum16 __ret = 0;						\	if (__skb_gro_checksum_validate_needed(skb, zero_okay, check))	\		__ret = __skb_gro_checksum_validate_complete(skb,	\				compute_pseudo(skb, proto));		\	if (!__ret)							\		skb_gro_incr_csum_unnecessary(skb);			\	__ret;								\}) #define skb_gro_checksum_validate(skb, proto, compute_pseudo)		\	__skb_gro_checksum_validate(skb, proto, false, 0, compute_pseudo) #define skb_gro_checksum_validate_zero_check(skb, proto, check,		\					     compute_pseudo)		\	__skb_gro_checksum_validate(skb, proto, true, check, compute_pseudo) #define skb_gro_checksum_simple_validate(skb)				\	__skb_gro_checksum_validate(skb, 0, false, 0, null_compute_pseudo) static inline bool __skb_gro_checksum_convert_check(struct sk_buff *skb){	return (NAPI_GRO_CB(skb)->csum_cnt == 0 &&		!NAPI_GRO_CB(skb)->csum_valid);} static inline void __skb_gro_checksum_convert(struct sk_buff *skb,					      __wsum pseudo){	NAPI_GRO_CB(skb)->csum = ~pseudo;	NAPI_GRO_CB(skb)->csum_valid = 1;} #define skb_gro_checksum_try_convert(skb, proto, compute_pseudo)	\do {									\	if (__skb_gro_checksum_convert_check(skb))			\		__skb_gro_checksum_convert(skb, 			\					   compute_pseudo(skb, proto));	\} while (0) struct gro_remcsum {	int offset;	__wsum delta;}; static inline void skb_gro_remcsum_init(struct gro_remcsum *grc){	grc->offset = 0;	grc->delta = 0;} static inline void *skb_gro_remcsum_process(struct sk_buff *skb, void *ptr,					    unsigned int off, size_t hdrlen,					    int start, int offset,					    struct gro_remcsum *grc,					    bool nopartial){	__wsum delta;	size_t plen = hdrlen + max_t(size_t, offset + sizeof(u16), start); 	BUG_ON(!NAPI_GRO_CB(skb)->csum_valid); 	if (!nopartial) {		NAPI_GRO_CB(skb)->gro_remcsum_start = off + hdrlen + start;		return ptr;	} 	ptr = skb_gro_header(skb, off + plen, off);	if (!ptr)		return NULL; 	delta = remcsum_adjust(ptr + hdrlen, NAPI_GRO_CB(skb)->csum,			       start, offset); 	/* Adjust skb->csum since we changed the packet */	NAPI_GRO_CB(skb)->csum = csum_add(NAPI_GRO_CB(skb)->csum, delta); 	grc->offset = off + hdrlen + offset;	grc->delta = delta; 	return ptr;} static inline void skb_gro_remcsum_cleanup(struct sk_buff *skb,					   struct gro_remcsum *grc){	void *ptr;	size_t plen = grc->offset + sizeof(u16); 	if (!grc->delta)		return; 	ptr = skb_gro_header(skb, plen, grc->offset);	if (!ptr)		return; 	remcsum_unadjust((__sum16 *)ptr, grc->delta);} #ifdef CONFIG_XFRM_OFFLOADstatic inline void skb_gro_flush_final(struct sk_buff *skb, struct sk_buff *pp, int flush){	if (PTR_ERR(pp) != -EINPROGRESS)		NAPI_GRO_CB(skb)->flush |= flush;}static inline void skb_gro_flush_final_remcsum(struct sk_buff *skb,					       struct sk_buff *pp,					       int flush,					       struct gro_remcsum *grc){	if (PTR_ERR(pp) != -EINPROGRESS) {		NAPI_GRO_CB(skb)->flush |= flush;		skb_gro_remcsum_cleanup(skb, grc);		skb->remcsum_offload = 0;	}}#elsestatic inline void skb_gro_flush_final(struct sk_buff *skb, struct sk_buff *pp, int flush){	NAPI_GRO_CB(skb)->flush |= flush;}static inline void skb_gro_flush_final_remcsum(struct sk_buff *skb,					       struct sk_buff *pp,					       int flush,					       struct gro_remcsum *grc){	NAPI_GRO_CB(skb)->flush |= flush;	skb_gro_remcsum_cleanup(skb, grc);	skb->remcsum_offload = 0;}#endif INDIRECT_CALLABLE_DECLARE(struct sk_buff *ipv6_gro_receive(struct list_head *,							   struct sk_buff *));INDIRECT_CALLABLE_DECLARE(int ipv6_gro_complete(struct sk_buff *, int));INDIRECT_CALLABLE_DECLARE(struct sk_buff *inet_gro_receive(struct list_head *,							   struct sk_buff *));INDIRECT_CALLABLE_DECLARE(int inet_gro_complete(struct sk_buff *, int)); INDIRECT_CALLABLE_DECLARE(struct sk_buff *udp4_gro_receive(struct list_head *,							   struct sk_buff *));INDIRECT_CALLABLE_DECLARE(int udp4_gro_complete(struct sk_buff *, int)); struct sk_buff *udp6_gro_receive(struct list_head *, struct sk_buff *);int udp6_gro_complete(struct sk_buff *, int); #define indirect_call_gro_receive_inet(cb, f2, f1, head, skb)	\({								\	unlikely(gro_recursion_inc_test(skb)) ?			\		NAPI_GRO_CB(skb)->flush |= 1, NULL :		\		INDIRECT_CALL_INET(cb, f2, f1, head, skb);	\}) struct sk_buff *udp_gro_receive(struct list_head *head, struct sk_buff *skb,				struct udphdr *uh, struct sock *sk);int udp_gro_complete(struct sk_buff *skb, int nhoff, udp_lookup_t lookup); static inline struct udphdr *udp_gro_udphdr(struct sk_buff *skb){	struct udphdr *uh;	unsigned int hlen, off; 	off  = skb_gro_offset(skb);	hlen = off + sizeof(*uh);	uh   = skb_gro_header(skb, hlen, off); 	return uh;} static inline __wsum ip6_gro_compute_pseudo(const struct sk_buff *skb,					    int proto){	const struct ipv6hdr *iph = skb_gro_network_header(skb); 	return ~csum_unfold(csum_ipv6_magic(&iph->saddr, &iph->daddr,					    skb_gro_len(skb), proto, 0));} static inline int inet_gro_flush(const struct iphdr *iph, const struct iphdr *iph2,				 struct sk_buff *p, bool inner){	const u32 id = ntohl(*(__be32 *)&iph->id);	const u32 id2 = ntohl(*(__be32 *)&iph2->id);	const u16 ipid_offset = (id >> 16) - (id2 >> 16);	const u16 count = NAPI_GRO_CB(p)->count; 	/* All fields must match except length and checksum. */	if ((iph->ttl ^ iph2->ttl) | (iph->tos ^ iph2->tos) | ((id ^ id2) & IP_DF))		return true; 	/* When we receive our second frame we can make a decision on if we	 * continue this flow as an atomic flow with a fixed ID or if we use	 * an incrementing ID.	 */	if (count == 1 && !ipid_offset)		NAPI_GRO_CB(p)->ip_fixedid |= 1 << inner; 	return ipid_offset ^ (count * !(NAPI_GRO_CB(p)->ip_fixedid & (1 << inner)));} static inline int ipv6_gro_flush(const struct ipv6hdr *iph, const struct ipv6hdr *iph2){	/* <Version:4><Traffic_Class:8><Flow_Label:20> */	__be32 first_word = *(__be32 *)iph ^ *(__be32 *)iph2; 	/* Flush if Traffic Class fields are different. */	return !!((first_word & htonl(0x0FF00000)) |		(__force __be32)(iph->hop_limit ^ iph2->hop_limit));} static inline int __gro_receive_network_flush(const void *th, const void *th2,					      struct sk_buff *p, const u16 diff,					      bool inner){	const void *nh = th - diff;	const void *nh2 = th2 - diff; 	if (((struct iphdr *)nh)->version == 6)		return ipv6_gro_flush(nh, nh2);	else		return inet_gro_flush(nh, nh2, p, inner);} static inline int gro_receive_network_flush(const void *th, const void *th2,					    struct sk_buff *p){	int off = skb_transport_offset(p);	int flush; 	flush = __gro_receive_network_flush(th, th2, p, off - NAPI_GRO_CB(p)->network_offset, false);	if (NAPI_GRO_CB(p)->encap_mark)		flush |= __gro_receive_network_flush(th, th2, p, off - NAPI_GRO_CB(p)->inner_network_offset, true); 	return flush;} 

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