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struct napi_gro_cb {	/* Virtual address of skb_shinfo(skb)->frags[0].page + offset. */	void	*frag0;	/* Length of frag0. */	unsigned int frag0_len;	/* 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;	/* Save the IP ID here and check when we get to the transport layer */	u16	flush_id;	/* Number of segments aggregated. */	u16	count;	/* Start offset for remote checksum offload */	u16	gro_remcsum_start;	/* jiffies when first packet was created/queued */	unsigned long age;	/* Used in ipv6_gro_receive() and foo-over-udp */	u16	proto;	/* 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;#define NAPI_GRO_FREE		  1#define NAPI_GRO_FREE_STOLEN_HEAD 2	/* Used in foo-over-udp, set in udp[46]_gro_receive */	u8	is_ipv6:1;	/* Used in GRE, set in fou/gue_gro_receive */	u8	is_fou:1;	/* Used to determine if flush_id can be ignored */	u8	is_atomic:1;	/* Number of gro_receive callbacks this packet already went through */	u8 recursion_counter:4;	/* 1 bit hole */	/* used to support CHECKSUM_COMPLETE for tunneling protocols */	__wsum	csum;	/* used in skb_gro_receive() slow path */	struct sk_buff *last;};

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