From: =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= <toke@redhat.com>
Date: Mon, 16 Sep 2019 14:33:42 +0200
Subject: libbpf: Remove getsockopt() check for XDP_OPTIONS
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Patch-mainline: v5.4-rc1
Git-commit: e0973a421c6e9d268db2157bcb8756e7ab4b4313
References: bsc#1154353

The xsk_socket__create() function fails and returns an error if it cannot
get the XDP_OPTIONS through getsockopt(). However, support for XDP_OPTIONS
was not added until kernel 5.3, so this means that creating XSK sockets
always fails on older kernels.

Since the option is just used to set the zero-copy flag in the xsk struct,
and that flag is not really used for anything yet, just remove the
getsockopt() call until a proper use for it is introduced.

Suggested-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 tools/lib/bpf/xsk.c |   11 -----------
 1 file changed, 11 deletions(-)

--- a/tools/lib/bpf/xsk.c
+++ b/tools/lib/bpf/xsk.c
@@ -65,7 +65,6 @@ struct xsk_socket {
 	int xsks_map_fd;
 	__u32 queue_id;
 	char ifname[IFNAMSIZ];
-	bool zc;
 };
 
 struct xsk_nl_info {
@@ -491,7 +490,6 @@ int xsk_socket__create(struct xsk_socket
 	void *rx_map = NULL, *tx_map = NULL;
 	struct sockaddr_xdp sxdp = {};
 	struct xdp_mmap_offsets off;
-	struct xdp_options opts;
 	struct xsk_socket *xsk;
 	socklen_t optlen;
 	int err;
@@ -611,15 +609,6 @@ int xsk_socket__create(struct xsk_socket
 
 	xsk->prog_fd = -1;
 
-	optlen = sizeof(opts);
-	err = getsockopt(xsk->fd, SOL_XDP, XDP_OPTIONS, &opts, &optlen);
-	if (err) {
-		err = -errno;
-		goto out_mmap_tx;
-	}
-
-	xsk->zc = opts.flags & XDP_OPTIONS_ZEROCOPY;
-
 	if (!(xsk->config.libbpf_flags & XSK_LIBBPF_FLAGS__INHIBIT_PROG_LOAD)) {
 		err = xsk_setup_xdp_prog(xsk);
 		if (err)