Register the bpf_map_sum_elem_count func for all programs, and update the map_ptr subtest of the test_progs test to test the new functionality.
The usage is allowed as long as the pointer to the map is trusted (when using tracing programs) or is a const pointer to map, as in the following example:
struct { __uint(type, BPF_MAP_TYPE_HASH); ... } hash SEC(".maps");
...
static inline int some_bpf_prog(void) { struct bpf_map *map = (struct bpf_map *)&hash; __s64 count;
count = bpf_map_sum_elem_count(map);
... }
Signed-off-by: Anton Protopopov aspsk@isovalent.com --- kernel/bpf/map_iter.c | 2 +- tools/testing/selftests/bpf/progs/map_ptr_kern.c | 5 +++++ 2 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/kernel/bpf/map_iter.c b/kernel/bpf/map_iter.c index 011adb41858e..6fc9dae9edc8 100644 --- a/kernel/bpf/map_iter.c +++ b/kernel/bpf/map_iter.c @@ -226,6 +226,6 @@ static const struct btf_kfunc_id_set bpf_map_iter_kfunc_set = {
static int init_subsystem(void) { - return register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, &bpf_map_iter_kfunc_set); + return register_btf_kfunc_id_set(BPF_PROG_TYPE_UNSPEC, &bpf_map_iter_kfunc_set); } late_initcall(init_subsystem); diff --git a/tools/testing/selftests/bpf/progs/map_ptr_kern.c b/tools/testing/selftests/bpf/progs/map_ptr_kern.c index db388f593d0a..3325da17ec81 100644 --- a/tools/testing/selftests/bpf/progs/map_ptr_kern.c +++ b/tools/testing/selftests/bpf/progs/map_ptr_kern.c @@ -103,6 +103,8 @@ struct { __type(value, __u32); } m_hash SEC(".maps");
+__s64 bpf_map_sum_elem_count(struct bpf_map *map) __ksym; + static inline int check_hash(void) { struct bpf_htab *hash = (struct bpf_htab *)&m_hash; @@ -115,6 +117,8 @@ static inline int check_hash(void) VERIFY(hash->elem_size == 64);
VERIFY(hash->count.counter == 0); + VERIFY(bpf_map_sum_elem_count(map) == 0); + for (i = 0; i < HALF_ENTRIES; ++i) { const __u32 key = i; const __u32 val = 1; @@ -123,6 +127,7 @@ static inline int check_hash(void) return 0; } VERIFY(hash->count.counter == HALF_ENTRIES); + VERIFY(bpf_map_sum_elem_count(map) == HALF_ENTRIES);
return 1; }