[PATCH bpf-next v5 1/8] libbpf: Add a helper for retrieving a map fd for a given name
From: Maciej Fijalkowski <hidden>
Date: 2019-02-01 00:20:20
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [library] (libbpf), the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Linus Torvalds
XDP samples are mostly cooperating with eBPF maps through their file descriptors. In case of a eBPF program that contains multiple maps it might be tiresome to iterate through them and call bpf_map__fd for each one. Add a helper mostly based on bpf_object__find_map_by_name, but instead of returning the struct bpf_map pointer, return map fd. Suggested-by: Jakub Kicinski <redacted> Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Reviewed-by: Jakub Kicinski <redacted> Acked-by: John Fastabend <john.fastabend@gmail.com> --- tools/lib/bpf/libbpf.c | 6 ++++++ tools/lib/bpf/libbpf.h | 3 +++ tools/lib/bpf/libbpf.map | 1 + 3 files changed, 10 insertions(+)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 2ccde17957e6..03bc01ca2577 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c@@ -2884,6 +2884,12 @@ bpf_object__find_map_by_name(struct bpf_object *obj, const char *name) return NULL; } +int +bpf_object__find_map_fd_by_name(struct bpf_object *obj, const char *name) +{ + return bpf_map__fd(bpf_object__find_map_by_name(obj, name)); +} + struct bpf_map * bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset) {
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index 62ae6cb93da1..931be6f3408c 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h@@ -264,6 +264,9 @@ struct bpf_map; LIBBPF_API struct bpf_map * bpf_object__find_map_by_name(struct bpf_object *obj, const char *name); +LIBBPF_API int +bpf_object__find_map_fd_by_name(struct bpf_object *obj, const char *name); + /* * Get bpf_map through the offset of corresponding struct bpf_map_def * in the BPF object file.
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index 266bc95d0142..b183c6c3b990 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map@@ -130,4 +130,5 @@ LIBBPF_0.0.2 { bpf_probe_helper; bpf_probe_map_type; bpf_probe_prog_type; + bpf_object__find_map_fd_by_name; } LIBBPF_0.0.1;
--
2.16.1