148 				    struct sk_buff *skb, unsigned int mtu)  in ip6_finish_output_gso_slowpath_drop()  argument
156 	 * egress MTU.  in ip6_finish_output_gso_slowpath_drop()
171 		/* Last GSO segment can be smaller than gso_size (and MTU).  in ip6_finish_output_gso_slowpath_drop()
175 		err = segs->len > mtu ?  in ip6_finish_output_gso_slowpath_drop()
186 				 struct sk_buff *skb, unsigned int mtu)  in ip6_finish_output_gso()  argument
189 	    !skb_gso_validate_network_len(skb, mtu))  in ip6_finish_output_gso()
190 		return ip6_finish_output_gso_slowpath_drop(net, sk, skb, mtu);  in ip6_finish_output_gso()
197 	unsigned int mtu;  in __ip6_finish_output()  local
207 	mtu = ip6_skb_dst_mtu(skb);  in __ip6_finish_output()
209 		return ip6_finish_output_gso(net, sk, skb, mtu);  in __ip6_finish_output()
211 	if (skb->len > mtu ||  in __ip6_finish_output()
283 	u32 mtu;  in ip6_xmit()  local
352 	mtu = dst_mtu(dst);  in ip6_xmit()
353 	if ((skb->len <= mtu) || skb->ignore_df || skb_is_gso(skb)) {  in ip6_xmit()
375 	ipv6_local_error((struct sock *)sk, EMSGSIZE, fl6, mtu);  in ip6_xmit()
483 static bool ip6_pkt_too_big(const struct sk_buff *skb, unsigned int mtu)  in ip6_pkt_too_big()  argument
485 	if (skb->len <= mtu)  in ip6_pkt_too_big()
489 	if (IP6CB(skb)->frag_max_size && IP6CB(skb)->frag_max_size > mtu)  in ip6_pkt_too_big()
495 	if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu))  in ip6_pkt_too_big()
509 	u32 mtu;  in ip6_forward()  local
641 	mtu = ip6_dst_mtu_maybe_forward(dst, true);  in ip6_forward()
642 	if (mtu < IPV6_MIN_MTU)  in ip6_forward()
643 		mtu = IPV6_MIN_MTU;  in ip6_forward()
645 	if (ip6_pkt_too_big(skb, mtu)) {  in ip6_forward()
648 		icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);  in ip6_forward()
766 void ip6_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int mtu,  in ip6_frag_init()  argument
775 	state->mtu = mtu;  in ip6_frag_init()
795 	/* IF: it doesn't fit, use 'mtu' - the data space left */  in ip6_frag_next()
796 	if (len > state->mtu)  in ip6_frag_next()
797 		len = state->mtu;  in ip6_frag_next()
872 	unsigned int mtu, hlen, nexthdr_offset;  in ip6_fragment()  local
885 	mtu = ip6_skb_dst_mtu(skb);  in ip6_fragment()
887 	/* We must not fragment if the socket is set to force MTU discovery  in ip6_fragment()
890 	if (unlikely(!skb->ignore_df && skb->len > mtu))  in ip6_fragment()
894 		if (IP6CB(skb)->frag_max_size > mtu)  in ip6_fragment()
898 		mtu = IP6CB(skb)->frag_max_size;  in ip6_fragment()
899 		if (mtu < IPV6_MIN_MTU)  in ip6_fragment()
900 			mtu = IPV6_MIN_MTU;  in ip6_fragment()
906 		if (frag_size && frag_size < mtu)  in ip6_fragment()
907 			mtu = frag_size;  in ip6_fragment()
909 	if (mtu < hlen + sizeof(struct frag_hdr) + 8)  in ip6_fragment()
911 	mtu -= hlen + sizeof(struct frag_hdr);  in ip6_fragment()
927 		if (first_len - hlen > mtu ||  in ip6_fragment()
935 			if (frag->len > mtu ||  in ip6_fragment()
1009 	ip6_frag_init(skb, hlen, mtu, rt->dst.dev->needed_tailroom,  in ip6_fragment()
1041 	icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);  in ip6_fragment()
1317 static void ip6_append_data_mtu(unsigned int *mtu,  in ip6_append_data_mtu()  argument
1327 			*mtu = orig_mtu - rt->dst.header_len;  in ip6_append_data_mtu()
1334 			*mtu = orig_mtu;  in ip6_append_data_mtu()
1336 		*maxfraglen = ((*mtu - fragheaderlen) & ~7)  in ip6_append_data_mtu()
1346 	unsigned int mtu, frag_size;  in ip6_setup_cork()  local
1390 		mtu = READ_ONCE(np->pmtudisc) >= IPV6_PMTUDISC_PROBE ?  in ip6_setup_cork()
1391 		      READ_ONCE(rt->dst.dev->mtu) : dst_mtu(&rt->dst);  in ip6_setup_cork()
1393 		mtu = READ_ONCE(np->pmtudisc) >= IPV6_PMTUDISC_PROBE ?  in ip6_setup_cork()
1394 			READ_ONCE(rt->dst.dev->mtu) : dst_mtu(xfrm_dst_path(&rt->dst));  in ip6_setup_cork()
1397 	if (frag_size && frag_size < mtu)  in ip6_setup_cork()
1398 		mtu = frag_size;  in ip6_setup_cork()
1400 	cork->base.fragsize = mtu;  in ip6_setup_cork()
1425 	unsigned int maxfraglen, fragheaderlen, mtu, orig_mtu, pmtu;  in __ip6_append_data()  local
1449 	mtu = cork->gso_size ? IP6_MAX_MTU : cork->fragsize;  in __ip6_append_data()
1450 	orig_mtu = mtu;  in __ip6_append_data()
1461 	if (mtu <= fragheaderlen ||  in __ip6_append_data()
1462 	    ((mtu - fragheaderlen) & ~7) + fragheaderlen <= sizeof(struct frag_hdr))  in __ip6_append_data()
1465 	maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen -  in __ip6_append_data()
1471 	if (headersize + transhdrlen > mtu)  in __ip6_append_data()
1474 	if (cork->length + length > mtu - headersize && ipc6->dontfrag &&  in __ip6_append_data()
1478 		ipv6_local_rxpmtu(sk, fl6, mtu - headersize +  in __ip6_append_data()
1486 		maxnonfragsize = mtu;  in __ip6_append_data()
1490 		pmtu = max_t(int, mtu - headersize + sizeof(struct ipv6hdr), 0);  in __ip6_append_data()
1500 	    length <= mtu - headersize &&  in __ip6_append_data()
1553 	 * Use MTU if total length of the message fits into the MTU.  in __ip6_append_data()
1573 		copy = (cork->length <= mtu ? mtu : maxfraglen) - skb->len;  in __ip6_append_data()
1590 			/* update mtu and maxfraglen if necessary */  in __ip6_append_data()
1592 				ip6_append_data_mtu(&mtu, &maxfraglen,  in __ip6_append_data()
1599 			 * If remaining data exceeds the mtu,  in __ip6_append_data()
1604 			if (datalen > (cork->length <= mtu ? mtu : maxfraglen) - fragheaderlen)  in __ip6_append_data()
1615 			 * (without MSG_MORE) fits into the MTU.  in __ip6_append_data()
1621 				alloclen = mtu;  in __ip6_append_data()