[Intel-wired-lan] [PATCH bpf-next 3/4] libbpf: handle AF_XDP sockets created with XDP_DIRECT bind flag.

[Sridhar Samudrala <sridhar.samudrala@intel.com>]

Don't allow an AF_XDP socket trying to bind with XDP_DIRECT bind
flag when a normal XDP program is already attached to the device,

Don't attach the default XDP program when AF_XDP socket is created
with XDP_DIRECT bind flag.

Signed-off-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
---
 tools/lib/bpf/xsk.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/tools/lib/bpf/xsk.c b/tools/lib/bpf/xsk.c
index d5f4900e5c54..953b479040cd 100644
--- a/tools/lib/bpf/xsk.c
+++ b/tools/lib/bpf/xsk.c
@@ -454,6 +454,9 @@ static int xsk_setup_xdp_prog(struct xsk_socket *xsk)
 		return err;
 
 	if (!prog_id) {
+		if (xsk->config.bind_flags & XDP_DIRECT)
+			return 0;
+
 		err = xsk_create_bpf_maps(xsk);
 		if (err)
 			return err;
@@ -464,6 +467,9 @@ static int xsk_setup_xdp_prog(struct xsk_socket *xsk)
 			return err;
 		}
 	} else {
+		if (xsk->config.bind_flags & XDP_DIRECT)
+			return -EEXIST;
+
 		xsk->prog_fd = bpf_prog_get_fd_by_id(prog_id);
 		err = xsk_lookup_bpf_maps(xsk);
 		if (err) {
-- 
2.14.5