[I/OAT]: TCP recv offload to I/OAT

Locks down user pages and sets up for DMA in tcp_recvmsg, then calls
dma_async_try_early_copy in tcp_v4_do_rcv

Signed-off-by: Chris Leech <christopher.leech@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 2 deletions

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 301eee726b0f..a50eb306e9e2 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1218,8 +1218,16 @@ process:
         bh_lock_sock(sk);
         ret = 0;
         if (!sock_owned_by_user(sk)) {
-                if (!tcp_prequeue(sk, skb))
-                        ret = tcp_v6_do_rcv(sk, skb);
+#ifdef CONFIG_NET_DMA
+                struct tcp_sock *tp = tcp_sk(sk);
+                if (tp->ucopy.dma_chan)
+                        ret = tcp_v6_do_rcv(sk, skb);
+                else
+#endif
+                {
+                        if (!tcp_prequeue(sk, skb))
+                                ret = tcp_v6_do_rcv(sk, skb);
+                }
         } else
                 sk_add_backlog(sk, skb);
         bh_unlock_sock(sk);