udp, passt: Introduce socket packet buffer, avoid getsockname() for UDP

This is in preparation for scatter-gather IO on the UDP receive path:
save a getsockname() syscall by setting a flag if we get the numbering
of all bound sockets in a strict sequence (expected, in practice) and
repurpose the tap buffer to be also a socket receive buffer, passing
it down to protocol handlers.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/passt.h b/passt.h
index 009cedb..22a91d6 100644
--- a/passt.h
+++ b/passt.h
@@ -14,6 +14,8 @@ struct tap_msg {
 	size_t l4_len;
 };
 
+#define SOCK_BUF_BYTES		(ETH_MAX_MTU * 4)
+
 #include "icmp.h"
 #include "tcp.h"
 #include "udp.h"
@@ -62,5 +64,5 @@ struct ctx {
 
 	struct icmp_ctx icmp;
 	struct tcp_ctx tcp;
-	struct tcp_ctx udp;
+	struct udp_ctx udp;
 };