From: Roman Gushchin <[email protected]> Introduce bpf_map__attach_struct_ops_opts(), an extended version of bpf_map__attach_struct_ops(), which takes additional struct bpf_struct_ops_opts argument.
This allows to pass a target_fd argument and the BPF_F_CGROUP_FD flag and attach the struct ops to a cgroup as a result. Signed-off-by: Roman Gushchin <[email protected]> --- tools/lib/bpf/libbpf.c | 20 +++++++++++++++++--- tools/lib/bpf/libbpf.h | 14 ++++++++++++++ tools/lib/bpf/libbpf.map | 1 + 3 files changed, 32 insertions(+), 3 deletions(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 1e8688975d16..a1b54da1ded2 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -13683,11 +13683,18 @@ static int bpf_link__detach_struct_ops(struct bpf_link *link) return close(link->fd); } -struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map) +struct bpf_link *bpf_map__attach_struct_ops_opts(const struct bpf_map *map, + const struct bpf_struct_ops_opts *opts) { + DECLARE_LIBBPF_OPTS(bpf_link_create_opts, link_opts); struct bpf_link_struct_ops *link; + int err, fd, target_fd; __u32 zero = 0; - int err, fd; + + if (!OPTS_VALID(opts, bpf_struct_ops_opts)) { + pr_warn("map '%s': invalid opts\n", map->name); + return libbpf_err_ptr(-EINVAL); + } if (!bpf_map__is_struct_ops(map)) { pr_warn("map '%s': can't attach non-struct_ops map\n", map->name); @@ -13724,7 +13731,9 @@ struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map) return &link->link; } - fd = bpf_link_create(map->fd, 0, BPF_STRUCT_OPS, NULL); + link_opts.flags = OPTS_GET(opts, flags, 0); + target_fd = OPTS_GET(opts, target_fd, 0); + fd = bpf_link_create(map->fd, target_fd, BPF_STRUCT_OPS, &link_opts); if (fd < 0) { free(link); return libbpf_err_ptr(fd); @@ -13736,6 +13745,11 @@ struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map) return &link->link; } +struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map) +{ + return bpf_map__attach_struct_ops_opts(map, NULL); +} + /* * Swap the back struct_ops of a link with a new struct_ops map. */ diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index bba4e8464396..18af178547ad 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -945,6 +945,20 @@ bpf_program__attach_cgroup_opts(const struct bpf_program *prog, int cgroup_fd, struct bpf_map; LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map); + +struct bpf_struct_ops_opts { + /* size of this struct, for forward/backward compatibility */ + size_t sz; + __u32 flags; + __u32 target_fd; + __u64 expected_revision; + size_t :0; +}; +#define bpf_struct_ops_opts__last_field expected_revision + +LIBBPF_API struct bpf_link * +bpf_map__attach_struct_ops_opts(const struct bpf_map *map, + const struct bpf_struct_ops_opts *opts); LIBBPF_API int bpf_link__update_map(struct bpf_link *link, const struct bpf_map *map); struct bpf_iter_attach_opts { diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index dfed8d60af05..6105619b5ecf 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -454,6 +454,7 @@ LIBBPF_1.7.0 { bpf_prog_assoc_struct_ops; bpf_program__assoc_struct_ops; btf__permute; + bpf_map__attach_struct_ops_opts; } LIBBPF_1.6.0; LIBBPF_1.8.0 { -- 2.43.0
