net: Convert GRO SKB handling to list_head.

Manage pending per-NAPI GRO packets via list_head.

Return an SKB pointer from the GRO receive handlers.  When GRO receive
handlers return non-NULL, it means that this SKB needs to be completed
at this time and removed from the NAPI queue.

Several operations are greatly simplified by this transformation,
especially timing out the oldest SKB in the list when gro_count
exceeds MAX_GRO_SKBS, and napi_gro_flush() which walks the queue
in reverse order.

Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 14 insertions, 14 deletions

diff --git a/net/ipv6/esp6_offload.c b/net/ipv6/esp6_offload.c
index 27f59b61f70f..ddfa533a84e5 100644
--- a/net/ipv6/esp6_offload.c
+++ b/net/ipv6/esp6_offload.c
@@ -49,8 +49,8 @@ static __u16 esp6_nexthdr_esp_offset(struct ipv6hdr *ipv6_hdr, int nhlen)
 	return 0;
 }
 
-static struct sk_buff **esp6_gro_receive(struct sk_buff **head,
-					 struct sk_buff *skb)
+static struct sk_buff *esp6_gro_receive(struct list_head *head,
+					struct sk_buff *skb)
 {
 	int offset = skb_gro_offset(skb);
 	struct xfrm_offload *xo;
diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c
index 5b3f2f89ef41..37ff4805b20c 100644
--- a/net/ipv6/ip6_offload.c
+++ b/net/ipv6/ip6_offload.c
@@ -163,11 +163,11 @@ static int ipv6_exthdrs_len(struct ipv6hdr *iph,
 	return len;
 }
 
-static struct sk_buff **ipv6_gro_receive(struct sk_buff **head,
-					 struct sk_buff *skb)
+static struct sk_buff *ipv6_gro_receive(struct list_head *head,
+					struct sk_buff *skb)
 {
 	const struct net_offload *ops;
-	struct sk_buff **pp = NULL;
+	struct sk_buff *pp = NULL;
 	struct sk_buff *p;
 	struct ipv6hdr *iph;
 	unsigned int nlen;
@@ -214,7 +214,7 @@ static struct sk_buff **ipv6_gro_receive(struct sk_buff **head,
 	flush--;
 	nlen = skb_network_header_len(skb);
 
-	for (p = *head; p; p = p->next) {
+	list_for_each_entry(p, head, list) {
 		const struct ipv6hdr *iph2;
 		__be32 first_word; /* <Version:4><Traffic_Class:8><Flow_Label:20> */
 
@@ -263,8 +263,8 @@ out:
 	return pp;
 }
 
-static struct sk_buff **sit_ip6ip6_gro_receive(struct sk_buff **head,
-					       struct sk_buff *skb)
+static struct sk_buff *sit_ip6ip6_gro_receive(struct list_head *head,
+					      struct sk_buff *skb)
 {
 	/* Common GRO receive for SIT and IP6IP6 */
 
@@ -278,8 +278,8 @@ static struct sk_buff **sit_ip6ip6_gro_receive(struct sk_buff **head,
 	return ipv6_gro_receive(head, skb);
 }
 
-static struct sk_buff **ip4ip6_gro_receive(struct sk_buff **head,
-					   struct sk_buff *skb)
+static struct sk_buff *ip4ip6_gro_receive(struct list_head *head,
+					  struct sk_buff *skb)
 {
 	/* Common GRO receive for SIT and IP6IP6 */
 
diff --git a/net/ipv6/tcpv6_offload.c b/net/ipv6/tcpv6_offload.c
index 278e49cd67d4..e72947c99454 100644
--- a/net/ipv6/tcpv6_offload.c
+++ b/net/ipv6/tcpv6_offload.c
@@ -15,8 +15,8 @@
 #include <net/ip6_checksum.h>
 #include "ip6_offload.h"
 
-static struct sk_buff **tcp6_gro_receive(struct sk_buff **head,
-					 struct sk_buff *skb)
+static struct sk_buff *tcp6_gro_receive(struct list_head *head,
+					struct sk_buff *skb)
 {
 	/* Don't bother verifying checksum if we're going to flush anyway. */
 	if (!NAPI_GRO_CB(skb)->flush &&
diff --git a/net/ipv6/udp_offload.c b/net/ipv6/udp_offload.c
index 03a2ff3fe1e6..95dee9ca8d22 100644
--- a/net/ipv6/udp_offload.c
+++ b/net/ipv6/udp_offload.c
@@ -114,8 +114,8 @@ out:
 	return segs;
 }
 
-static struct sk_buff **udp6_gro_receive(struct sk_buff **head,
-					 struct sk_buff *skb)
+static struct sk_buff *udp6_gro_receive(struct list_head *head,
+					struct sk_buff *skb)
 {
 	struct udphdr *uh = udp_gro_udphdr(skb);