gue: Use checksum partial with remote checksum offload

Change remote checksum handling to set checksum partial as default
behavior. Added an iflink parameter to configure not using
checksum partial (calling csum_partial to update checksum).

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 22 insertions, 6 deletions

diff --git a/net/ipv4/fou.c b/net/ipv4/fou.c
index d320f575cc62..ff069f6597ac 100644
--- a/net/ipv4/fou.c
+++ b/net/ipv4/fou.c
@@ -22,14 +22,18 @@ static LIST_HEAD(fou_list);
 struct fou {
         struct socket *sock;
         u8 protocol;
+        u8 flags;
         u16 port;
         struct udp_offload udp_offloads;
         struct list_head list;
 };
 
+#define FOU_F_REMCSUM_NOPARTIAL BIT(0)
+
 struct fou_cfg {
         u16 type;
         u8 protocol;
+        u8 flags;
         struct udp_port_cfg udp_config;
 };
 
@@ -64,7 +68,8 @@ static int fou_udp_recv(struct sock *sk, struct sk_buff *skb)
 }
 
 static struct guehdr *gue_remcsum(struct sk_buff *skb, struct guehdr *guehdr,
-                                  void *data, size_t hdrlen, u8 ipproto)
+                                  void *data, size_t hdrlen, u8 ipproto,
+                                  bool nopartial)
 {
         __be16 *pd = data;
         size_t start = ntohs(pd[0]);
@@ -75,7 +80,8 @@ static struct guehdr *gue_remcsum(struct sk_buff *skb, struct guehdr *guehdr,
                 return NULL;
         guehdr = (struct guehdr *)&udp_hdr(skb)[1];
 
-        skb_remcsum_process(skb, (void *)guehdr + hdrlen, start, offset, true);
+        skb_remcsum_process(skb, (void *)guehdr + hdrlen,
+                            start, offset, nopartial);
 
         return guehdr;
 }
@@ -136,7 +142,9 @@ static int gue_udp_recv(struct sock *sk, struct sk_buff *skb)
 
                 if (flags & GUE_PFLAG_REMCSUM) {
                         guehdr = gue_remcsum(skb, guehdr, data + doffset,
-                                             hdrlen, guehdr->proto_ctype);
+                                             hdrlen, guehdr->proto_ctype,
+                                             !!(fou->flags &
+                                                FOU_F_REMCSUM_NOPARTIAL));
                         if (!guehdr)
                                 goto drop;
 
@@ -209,7 +217,7 @@ out_unlock:
 static struct guehdr *gue_gro_remcsum(struct sk_buff *skb, unsigned int off,
                                       struct guehdr *guehdr, void *data,
                                       size_t hdrlen, u8 ipproto,
-                                      struct gro_remcsum *grc)
+                                      struct gro_remcsum *grc, bool nopartial)
 {
         __be16 *pd = data;
         size_t start = ntohs(pd[0]);
@@ -230,7 +238,7 @@ static struct guehdr *gue_gro_remcsum(struct sk_buff *skb, unsigned int off,
         }
 
         skb_gro_remcsum_process(skb, (void *)guehdr + hdrlen,
-                                start, offset, grc, true);
+                                start, offset, grc, nopartial);
 
         skb->remcsum_offload = 1;
 
@@ -250,6 +258,7 @@ static struct sk_buff **gue_gro_receive(struct sk_buff **head,
         void *data;
         u16 doffset = 0;
         int flush = 1;
+        struct fou *fou = container_of(uoff, struct fou, udp_offloads);
         struct gro_remcsum grc;
 
         skb_gro_remcsum_init(&grc);
@@ -294,7 +303,9 @@ static struct sk_buff **gue_gro_receive(struct sk_buff **head,
                 if (flags & GUE_PFLAG_REMCSUM) {
                         guehdr = gue_gro_remcsum(skb, off, guehdr,
                                                  data + doffset, hdrlen,
-                                                 guehdr->proto_ctype, &grc);
+                                                 guehdr->proto_ctype, &grc,
+                                                 !!(fou->flags &
+                                                    FOU_F_REMCSUM_NOPARTIAL));
                         if (!guehdr)
                                 goto out;
 
@@ -455,6 +466,7 @@ static int fou_create(struct net *net, struct fou_cfg *cfg,
 
         sk = sock->sk;
 
+        fou->flags = cfg->flags;
         fou->port = cfg->udp_config.local_udp_port;
 
         /* Initial for fou type */
@@ -541,6 +553,7 @@ static struct nla_policy fou_nl_policy[FOU_ATTR_MAX + 1] = {
         [FOU_ATTR_AF] = { .type = NLA_U8, },
         [FOU_ATTR_IPPROTO] = { .type = NLA_U8, },
         [FOU_ATTR_TYPE] = { .type = NLA_U8, },
+        [FOU_ATTR_REMCSUM_NOPARTIAL] = { .type = NLA_FLAG, },
 };
 
 static int parse_nl_config(struct genl_info *info,
@@ -571,6 +584,9 @@ static int parse_nl_config(struct genl_info *info,
         if (info->attrs[FOU_ATTR_TYPE])
                 cfg->type = nla_get_u8(info->attrs[FOU_ATTR_TYPE]);
 
+        if (info->attrs[FOU_ATTR_REMCSUM_NOPARTIAL])
+                cfg->flags |= FOU_F_REMCSUM_NOPARTIAL;
+
         return 0;
 }