Commit 5fa12739 authored by Edward Cree's avatar Edward Cree Committed by David S. Miller
Browse files

net: ipv4: listify ip_rcv_finish 



ip_rcv_finish_core(), if it does not drop, sets skb->dst by either early
 demux or route lookup.  The last step, calling dst_input(skb), is left to
 the caller; in the listified case, we split to form sublists with a common
 dst, but then ip_sublist_rcv_finish() just calls dst_input(skb) in a loop.
The next step in listification would thus be to add a list_input() method
 to struct dst_entry.

Early demux is an indirect call based on iph->protocol; this is another
 opportunity for listification which is not taken here (it would require
 slicing up ip_rcv_finish_core() to allow splitting on protocol changes).

Signed-off-by: default avatarEdward Cree <ecree@solarflare.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 17266ee9

net/ipv4/ip_input.c

+48 −6
Original line number Diff line number Diff line
@@ -307,7 +307,8 @@ drop: 
	return true;

}



static int ip_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb)

static int ip_rcv_finish_core(struct net *net, struct sock *sk,

			      struct sk_buff *skb)

{

	const struct iphdr *iph = ip_hdr(skb);

	int (*edemux)(struct sk_buff *skb);
@@ -393,7 +394,7 @@ static int ip_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb) 
			goto drop;

	}



	return dst_input(skb);

	return NET_RX_SUCCESS;



drop:

	kfree_skb(skb);
@@ -405,6 +406,15 @@ drop_error: 
	goto drop;

}



static int ip_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb)

{

	int ret = ip_rcv_finish_core(net, sk, skb);



	if (ret != NET_RX_DROP)

		ret = dst_input(skb);

	return ret;

}



/*

 * 	Main IP Receive routine.

 */
@@ -515,15 +525,47 @@ int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, 
		       ip_rcv_finish);

}



static void ip_sublist_rcv(struct list_head *head, struct net_device *dev,

			   struct net *net)

static void ip_sublist_rcv_finish(struct list_head *head)

{

	struct sk_buff *skb, *next;



	list_for_each_entry_safe(skb, next, head, list)

		dst_input(skb);

}



static void ip_list_rcv_finish(struct net *net, struct sock *sk,

			       struct list_head *head)

{

	struct dst_entry *curr_dst = NULL;

	struct sk_buff *skb, *next;

	struct list_head sublist;



	list_for_each_entry_safe(skb, next, head, list) {

		struct dst_entry *dst;



		if (ip_rcv_finish_core(net, sk, skb) == NET_RX_DROP)

			continue;



		dst = skb_dst(skb);

		if (curr_dst != dst) {

			/* dispatch old sublist */

			list_cut_before(&sublist, head, &skb->list);

			if (!list_empty(&sublist))

				ip_sublist_rcv_finish(&sublist);

			/* start new sublist */

			curr_dst = dst;

		}

	}

	/* dispatch final sublist */

	ip_sublist_rcv_finish(head);

}



static void ip_sublist_rcv(struct list_head *head, struct net_device *dev,

			   struct net *net)

{

	NF_HOOK_LIST(NFPROTO_IPV4, NF_INET_PRE_ROUTING, net, NULL,

		     head, dev, NULL, ip_rcv_finish);

	list_for_each_entry_safe(skb, next, head, list)

		ip_rcv_finish(net, NULL, skb);

	ip_list_rcv_finish(net, NULL, head);

}



/* Receive a list of IP packets */

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