libbpf: Add support for BPF XDP link

Sync UAPI header and add support for using bpf_link-based XDP attachment.
Make xdp/ prog type set expected attach type. Kernel didn't enforce
attach_type for XDP programs before, so there is no backwards compatiblity
issues there.

Also fix section_names selftest to recognize that xdp prog types now have
expected attach type.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200722064603.3350758-8-andriin@fb.com
This commit is contained in:
Andrii Nakryiko
2020-07-21 23:46:00 -07:00
committed by Alexei Starovoitov
parent c1931c9784
commit dc8698cac7
5 changed files with 21 additions and 3 deletions

View File

@@ -230,6 +230,7 @@ enum bpf_attach_type {
BPF_CGROUP_INET_SOCK_RELEASE,
BPF_XDP_CPUMAP,
BPF_SK_LOOKUP,
BPF_XDP,
__MAX_BPF_ATTACH_TYPE
};
@@ -242,6 +243,7 @@ enum bpf_link_type {
BPF_LINK_TYPE_CGROUP = 3,
BPF_LINK_TYPE_ITER = 4,
BPF_LINK_TYPE_NETNS = 5,
BPF_LINK_TYPE_XDP = 6,
MAX_BPF_LINK_TYPE,
};
@@ -614,7 +616,10 @@ union bpf_attr {
struct { /* struct used by BPF_LINK_CREATE command */
__u32 prog_fd; /* eBPF program to attach */
__u32 target_fd; /* object to attach to */
union {
__u32 target_fd; /* object to attach to */
__u32 target_ifindex; /* target ifindex */
};
__u32 attach_type; /* attach type */
__u32 flags; /* extra flags */
} link_create;
@@ -4064,6 +4069,9 @@ struct bpf_link_info {
__u32 netns_ino;
__u32 attach_type;
} netns;
struct {
__u32 ifindex;
} xdp;
};
} __attribute__((aligned(8)));