libbpf: Allow for creating Rx or Tx only AF_XDP sockets

The libbpf AF_XDP code is extended to allow for the creation of Rx only or Tx only sockets. Previously it returned an error if the socket was not initialized for both Rx and Tx. Signed-off-by: Magnus Karlsson <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Tested-by: William Tu <[email protected]> Acked-by: Jonathan Lemon <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
ambv · Nov 11, 2019 · a68977d · a68977d
1 parent 2e5d72c
commit a68977d
Showing 1 changed file with 3 additions and 2 deletions.
diff --git a/tools/lib/bpf/xsk.c b/tools/lib/bpf/xsk.c
@@ -562,7 +562,8 @@ static int xsk_setup_xdp_prog(struct xsk_socket *xsk)
 		}
 	}
 
-	err = xsk_set_bpf_maps(xsk);
+	if (xsk->rx)
+		err = xsk_set_bpf_maps(xsk);
 	if (err) {
 		xsk_delete_bpf_maps(xsk);
 		close(xsk->prog_fd);
@@ -583,7 +584,7 @@ int xsk_socket__create(struct xsk_socket **xsk_ptr, const char *ifname,
 	struct xsk_socket *xsk;
 	int err;
 
-	if (!umem || !xsk_ptr || !rx || !tx)
+	if (!umem || !xsk_ptr || !(rx || tx))
 		return -EFAULT;
 
 	xsk = calloc(1, sizeof(*xsk));