From 6f3189f38a3e995232e028a4c341164c4aca1b20 Mon Sep 17 00:00:00 2001 From: Daniel Xu Date: Sun, 28 Jan 2024 18:24:08 -0700 Subject: bpf: treewide: Annotate BPF kfuncs in BTF This commit marks kfuncs as such inside the .BTF_ids section. The upshot of these annotations is that we'll be able to automatically generate kfunc prototypes for downstream users. The process is as follows: 1. In source, use BTF_KFUNCS_START/END macro pair to mark kfuncs 2. During build, pahole injects into BTF a "bpf_kfunc" BTF_DECL_TAG for each function inside BTF_KFUNCS sets 3. At runtime, vmlinux or module BTF is made available in sysfs 4. At runtime, bpftool (or similar) can look at provided BTF and generate appropriate prototypes for functions with "bpf_kfunc" tag To ensure future kfunc are similarly tagged, we now also return error inside kfunc registration for untagged kfuncs. For vmlinux kfuncs, we also WARN(), as initcall machinery does not handle errors. Signed-off-by: Daniel Xu Acked-by: Benjamin Tissoires Link: https://lore.kernel.org/r/e55150ceecbf0a5d961e608941165c0bee7bc943.1706491398.git.dxu@dxuuu.xyz Signed-off-by: Alexei Starovoitov --- fs/verity/measure.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/verity/measure.c') diff --git a/fs/verity/measure.c b/fs/verity/measure.c index bf7a5f4cccaf..3969d54158d1 100644 --- a/fs/verity/measure.c +++ b/fs/verity/measure.c @@ -159,9 +159,9 @@ __bpf_kfunc int bpf_get_fsverity_digest(struct file *file, struct bpf_dynptr_ker __bpf_kfunc_end_defs(); -BTF_SET8_START(fsverity_set_ids) +BTF_KFUNCS_START(fsverity_set_ids) BTF_ID_FLAGS(func, bpf_get_fsverity_digest, KF_TRUSTED_ARGS) -BTF_SET8_END(fsverity_set_ids) +BTF_KFUNCS_END(fsverity_set_ids) static int bpf_get_fsverity_digest_filter(const struct bpf_prog *prog, u32 kfunc_id) { -- cgit v1.2.3