From: Alexei Starovoitov <ast@xxxxxxxxxx>
Introduce bpf_map__initial_value() to read initial contents
of mmaped data/rodata/bss maps.
Note that bpf_map__set_initial_value() doesn't allow modifying
kconfig map while bpf_map__initial_value() allows reading
its values.
Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
---
tools/lib/bpf/libbpf.c | 8 ++++++++
tools/lib/bpf/libbpf.h | 1 +
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 3f7d184c7e3a..a8089e3e4da4 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -9750,6 +9750,14 @@ int bpf_map__set_initial_value(struct bpf_map *map,
return 0;
}
+const void *bpf_map__initial_value(struct bpf_map *map, size_t *psize)
+{
+ if (!map->mmaped)
+ return NULL;
+ *psize = map->def.value_size;
+ return map->mmaped;
+}
+
bool bpf_map__is_offload_neutral(const struct bpf_map *map)
{
return map->def.type == BPF_MAP_TYPE_PERF_EVENT_ARRAY;
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index 8cf168f3717c..a50eab5fec0a 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -471,6 +471,7 @@ LIBBPF_API int bpf_map__set_priv(struct bpf_map *map, void *priv,
LIBBPF_API void *bpf_map__priv(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_initial_value(struct bpf_map *map,
const void *data, size_t size);
+LIBBPF_API const void *bpf_map__initial_value(struct bpf_map *map, size_t *psize);
LIBBPF_API bool bpf_map__is_offload_neutral(const struct bpf_map *map);
LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path);
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index 889ee2f3611c..dd0f24370939 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -359,6 +359,7 @@ LIBBPF_0.4.0 {
bpf_linker__finalize;
bpf_linker__free;
bpf_linker__new;
+ bpf_map__initial_value;
bpf_map__inner_map;
bpf_object__gen_loader;
bpf_object__set_kversion;
--
2.30.2
