From: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx>
Add functions to get XDP/XSK supported function of netdev over route
netlink interface. These functions provide functionalities that are
going to be used in upcoming change.
The newly added bpf_xdp_query_features takes a fflags_cnt parameter,
which denotes the number of elements in the output fflags array. This
must be at least 1 and maybe greater than XDP_FEATURES_WORDS. The
function only writes to words which is min of fflags_cnt and
XDP_FEATURES_WORDS.
Co-developed-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>
Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>
Co-developed-by: Marek Majtyka <alardam@xxxxxxxxx>
Signed-off-by: Marek Majtyka <alardam@xxxxxxxxx>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx>
---
tools/lib/bpf/libbpf.h | 1 +
tools/lib/bpf/libbpf.map | 1 +
tools/lib/bpf/netlink.c | 62 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 64 insertions(+)
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index eee883f007f9..9d102eb5007e 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -967,6 +967,7 @@ LIBBPF_API int bpf_xdp_detach(int ifindex, __u32 flags,
const struct bpf_xdp_attach_opts *opts);
LIBBPF_API int bpf_xdp_query(int ifindex, int flags, struct bpf_xdp_query_opts *opts);
LIBBPF_API int bpf_xdp_query_id(int ifindex, int flags, __u32 *prog_id);
+LIBBPF_API int bpf_xdp_query_features(int ifindex, __u32 *fflags, __u32 *fflags_cnt);
/* TC related API */
enum bpf_tc_attach_point {
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index 71bf5691a689..9c2abb58fa4b 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -362,6 +362,7 @@ LIBBPF_1.0.0 {
bpf_program__set_autoattach;
btf__add_enum64;
btf__add_enum64_value;
+ bpf_xdp_query_features;
libbpf_bpf_attach_type_str;
libbpf_bpf_link_type_str;
libbpf_bpf_map_type_str;
diff --git a/tools/lib/bpf/netlink.c b/tools/lib/bpf/netlink.c
index 35104580870c..6fd424cde58b 100644
--- a/tools/lib/bpf/netlink.c
+++ b/tools/lib/bpf/netlink.c
@@ -9,6 +9,7 @@
#include <linux/if_ether.h>
#include <linux/pkt_cls.h>
#include <linux/rtnetlink.h>
+#include <linux/xdp_features.h>
#include <sys/socket.h>
#include <errno.h>
#include <time.h>
@@ -41,6 +42,12 @@ struct xdp_id_md {
struct xdp_link_info info;
};
+struct xdp_features_md {
+ int ifindex;
+ __u32 *flags;
+ __u32 *flags_cnt;
+};
+
static int libbpf_netlink_open(__u32 *nl_pid)
{
struct sockaddr_nl sa;
@@ -357,6 +364,39 @@ static int get_xdp_info(void *cookie, void *msg, struct nlattr **tb)
return 0;
}
+static int bpf_get_xdp_features(void *cookie, void *msg, struct nlattr **tb)
+{
+ struct nlattr *xdp_tb[IFLA_XDP_FEATURES_BITS_WORD + 1];
+ struct xdp_features_md *md = cookie;
+ struct ifinfomsg *ifinfo = msg;
+ int ret, i, words;
+
+ if (md->ifindex && md->ifindex != ifinfo->ifi_index)
+ return 0;
+
+ if (!tb[IFLA_XDP_FEATURES])
+ return 0;
+
+ words = min(XDP_FEATURES_WORDS, *md->flags_cnt);
+ for (i = 0; i < words; ++i)
+ md->flags[i] = 0;
+
+ ret = libbpf_nla_parse_nested(xdp_tb, XDP_FEATURES_WORDS,
+ tb[IFLA_XDP_FEATURES], NULL);
+ if (ret)
+ return ret;
+
+ *md->flags_cnt = words;
+ for (i = 0; i < words; ++i) {
+ if (!xdp_tb[IFLA_XDP_FEATURES_BITS_WORD])
+ continue;
+
+ md->flags[i] = libbpf_nla_getattr_u32(xdp_tb[IFLA_XDP_FEATURES_BITS_WORD]);
+ }
+
+ return 0;
+}
+
int bpf_xdp_query(int ifindex, int xdp_flags, struct bpf_xdp_query_opts *opts)
{
struct libbpf_nla_req req = {
@@ -421,6 +461,28 @@ int bpf_xdp_query_id(int ifindex, int flags, __u32 *prog_id)
return 0;
}
+int bpf_xdp_query_features(int ifindex, __u32 *xdp_fflags, __u32 *fflags_cnt)
+{
+ struct libbpf_nla_req req = {
+ .nh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
+ .nh.nlmsg_type = RTM_GETLINK,
+ .nh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
+ .ifinfo.ifi_family = AF_PACKET,
+ };
+ struct xdp_features_md md = {};
+ int ret;
+
+ if (!xdp_fflags || !fflags_cnt)
+ return -EINVAL;
+
+ md.ifindex = ifindex;
+ md.flags = xdp_fflags;
+ md.flags_cnt = fflags_cnt;
+
+ ret = libbpf_netlink_send_recv(&req, __dump_link_nlmsg,
+ bpf_get_xdp_features, &md);
+ return libbpf_err(ret);
+}
typedef int (*qdisc_config_t)(struct libbpf_nla_req *req);
--
2.38.1
