From 189cf5a4a7d5e0349f3079f05a8ccf4e4a2f0c3e Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Mon, 15 Apr 2019 16:48:07 -0700 Subject: [PATCH] btf: add support for VAR and DATASEC in btf_dedup() This patch adds support for VAR and DATASEC in btf_dedup(). VAR/DATASEC are never deduplicated, but they need to be processed anyway as types they refer to might need to be remapped due to deduplication and compaction. Cc: Daniel Borkmann Cc: Yonghong Song Cc: Alexei Starovoitov Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann --- tools/lib/bpf/btf.c | 29 +++++++++++++++++++++++++++-- 1 file changed, 27 insertions(+), 2 deletions(-) diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c index 701e7e28ada3..75eaf10b9e1a 100644 --- a/tools/lib/bpf/btf.c +++ b/tools/lib/bpf/btf.c @@ -1354,8 +1354,16 @@ static struct btf_dedup *btf_dedup_new(struct btf *btf, struct btf_ext *btf_ext, } /* special BTF "void" type is made canonical immediately */ d->map[0] = 0; - for (i = 1; i <= btf->nr_types; i++) - d->map[i] = BTF_UNPROCESSED_ID; + for (i = 1; i <= btf->nr_types; i++) { + struct btf_type *t = d->btf->types[i]; + __u16 kind = BTF_INFO_KIND(t->info); + + /* VAR and DATASEC are never deduped and are self-canonical */ + if (kind == BTF_KIND_VAR || kind == BTF_KIND_DATASEC) + d->map[i] = i; + else + d->map[i] = BTF_UNPROCESSED_ID; + } d->hypot_map = malloc(sizeof(__u32) * (1 + btf->nr_types)); if (!d->hypot_map) { @@ -1946,6 +1954,8 @@ static int btf_dedup_prim_type(struct btf_dedup *d, __u32 type_id) case BTF_KIND_UNION: case BTF_KIND_FUNC: case BTF_KIND_FUNC_PROTO: + case BTF_KIND_VAR: + case BTF_KIND_DATASEC: return 0; case BTF_KIND_INT: @@ -2699,6 +2709,7 @@ static int btf_dedup_remap_type(struct btf_dedup *d, __u32 type_id) case BTF_KIND_PTR: case BTF_KIND_TYPEDEF: case BTF_KIND_FUNC: + case BTF_KIND_VAR: r = btf_dedup_remap_type_id(d, t->type); if (r < 0) return r; @@ -2753,6 +2764,20 @@ static int btf_dedup_remap_type(struct btf_dedup *d, __u32 type_id) break; } + case BTF_KIND_DATASEC: { + struct btf_var_secinfo *var = (struct btf_var_secinfo *)(t + 1); + __u16 vlen = BTF_INFO_VLEN(t->info); + + for (i = 0; i < vlen; i++) { + r = btf_dedup_remap_type_id(d, var->type); + if (r < 0) + return r; + var->type = r; + var++; + } + break; + } + default: return -EINVAL; }