bpf: selftests: Add kfunc_call test

This patch adds a few kernel function bpf_kfunc_call_test*() for the
selftest's test_run purpose.  They will be allowed for tc_cls prog.

The selftest calling the kernel function bpf_kfunc_call_test*()
is also added in this patch.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015252.1551395-1-kafai@fb.com

1 files changed, 6 insertions, 0 deletions

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index b5b7967e3ff3..9fdd839b418c 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1532,6 +1532,7 @@ int bpf_prog_test_run_raw_tp(struct bpf_prog *prog,
 int bpf_prog_test_run_sk_lookup(struct bpf_prog *prog,
 				const union bpf_attr *kattr,
 				union bpf_attr __user *uattr);
+bool bpf_prog_test_check_kfunc_call(u32 kfunc_id);
 bool btf_ctx_access(int off, int size, enum bpf_access_type type,
 		    const struct bpf_prog *prog,
 		    struct bpf_insn_access_aux *info);
@@ -1731,6 +1732,11 @@ static inline int bpf_prog_test_run_sk_lookup(struct bpf_prog *prog,
 	return -ENOTSUPP;
 }
 
+static inline bool bpf_prog_test_check_kfunc_call(u32 kfunc_id)
+{
+	return false;
+}
+
 static inline void bpf_map_put(struct bpf_map *map)
 {
 }