This change merges the two existing implementations of the
bpf_core_types_are_compat() function into relo_core.c, inheriting the
recursion tracking from the kernel and the usage of
btf_kind_core_compat() from libbpf. The kernel is left untouched and
will be adjusted subsequently.
Signed-off-by: Daniel Müller <deso@xxxxxxxxxx>
---
tools/lib/bpf/libbpf.c | 72 +-----------------------------------
tools/lib/bpf/relo_core.c | 78 +++++++++++++++++++++++++++++++++++++++
tools/lib/bpf/relo_core.h | 2 +
3 files changed, 81 insertions(+), 71 deletions(-)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 49e359c..ca912c 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -5732,77 +5732,7 @@ bpf_core_find_cands(struct bpf_object *obj, const struct btf *local_btf, __u32 l
int bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id,
const struct btf *targ_btf, __u32 targ_id)
{
- const struct btf_type *local_type, *targ_type;
- int depth = 32; /* max recursion depth */
-
- /* caller made sure that names match (ignoring flavor suffix) */
- local_type = btf__type_by_id(local_btf, local_id);
- targ_type = btf__type_by_id(targ_btf, targ_id);
- if (!btf_kind_core_compat(local_type, targ_type))
- return 0;
-
-recur:
- depth--;
- if (depth < 0)
- return -EINVAL;
-
- local_type = skip_mods_and_typedefs(local_btf, local_id, &local_id);
- targ_type = skip_mods_and_typedefs(targ_btf, targ_id, &targ_id);
- if (!local_type || !targ_type)
- return -EINVAL;
-
- if (!btf_kind_core_compat(local_type, targ_type))
- return 0;
-
- switch (btf_kind(local_type)) {
- case BTF_KIND_UNKN:
- case BTF_KIND_STRUCT:
- case BTF_KIND_UNION:
- case BTF_KIND_ENUM:
- case BTF_KIND_ENUM64:
- case BTF_KIND_FWD:
- return 1;
- case BTF_KIND_INT:
- /* just reject deprecated bitfield-like integers; all other
- * integers are by default compatible between each other
- */
- return btf_int_offset(local_type) == 0 && btf_int_offset(targ_type) == 0;
- case BTF_KIND_PTR:
- local_id = local_type->type;
- targ_id = targ_type->type;
- goto recur;
- case BTF_KIND_ARRAY:
- local_id = btf_array(local_type)->type;
- targ_id = btf_array(targ_type)->type;
- goto recur;
- case BTF_KIND_FUNC_PROTO: {
- struct btf_param *local_p = btf_params(local_type);
- struct btf_param *targ_p = btf_params(targ_type);
- __u16 local_vlen = btf_vlen(local_type);
- __u16 targ_vlen = btf_vlen(targ_type);
- int i, err;
-
- if (local_vlen != targ_vlen)
- return 0;
-
- for (i = 0; i < local_vlen; i++, local_p++, targ_p++) {
- skip_mods_and_typedefs(local_btf, local_p->type, &local_id);
- skip_mods_and_typedefs(targ_btf, targ_p->type, &targ_id);
- err = bpf_core_types_are_compat(local_btf, local_id, targ_btf, targ_id);
- if (err <= 0)
- return err;
- }
-
- /* tail recurse for return type check */
- skip_mods_and_typedefs(local_btf, local_type->type, &local_id);
- skip_mods_and_typedefs(targ_btf, targ_type->type, &targ_id);
- goto recur;
- }
- default:
- pr_warn("unexpected kind %s relocated, local [%d], target [%d]\n",
- btf_kind_str(local_type), local_id, targ_id);
- return 0;
- }
+ return bpf_core_types_are_compat_recur(local_btf, local_id, targ_btf, targ_id, INT_MAX);
}
static size_t bpf_core_hash_fn(const void *key, void *ctx)
diff --git a/tools/lib/bpf/relo_core.c b/tools/lib/bpf/relo_core.c
index 6ad3c3..e54370 100644
--- a/tools/lib/bpf/relo_core.c
+++ b/tools/lib/bpf/relo_core.c
@@ -141,6 +141,84 @@ static bool core_relo_is_enumval_based(enum bpf_core_relo_kind kind)
}
}
+int bpf_core_types_are_compat_recur(const struct btf *local_btf, __u32 local_id,
+ const struct btf *targ_btf, __u32 targ_id, int level)
+{
+ const struct btf_type *local_type, *targ_type;
+ int depth = 32; /* max recursion depth */
+
+ /* caller made sure that names match (ignoring flavor suffix) */
+ local_type = btf_type_by_id(local_btf, local_id);
+ targ_type = btf_type_by_id(targ_btf, targ_id);
+ if (!btf_kind_core_compat(local_type, targ_type))
+ return 0;
+
+recur:
+ depth--;
+ if (depth < 0)
+ return -EINVAL;
+
+ local_type = skip_mods_and_typedefs(local_btf, local_id, &local_id);
+ targ_type = skip_mods_and_typedefs(targ_btf, targ_id, &targ_id);
+ if (!local_type || !targ_type)
+ return -EINVAL;
+
+ if (!btf_kind_core_compat(local_type, targ_type))
+ return 0;
+
+ switch (btf_kind(local_type)) {
+ case BTF_KIND_UNKN:
+ case BTF_KIND_STRUCT:
+ case BTF_KIND_UNION:
+ case BTF_KIND_ENUM:
+ case BTF_KIND_FWD:
+ case BTF_KIND_ENUM64:
+ return 1;
+ case BTF_KIND_INT:
+ /* just reject deprecated bitfield-like integers; all other
+ * integers are by default compatible between each other
+ */
+ return btf_int_offset(local_type) == 0 && btf_int_offset(targ_type) == 0;
+ case BTF_KIND_PTR:
+ local_id = local_type->type;
+ targ_id = targ_type->type;
+ goto recur;
+ case BTF_KIND_ARRAY:
+ local_id = btf_array(local_type)->type;
+ targ_id = btf_array(targ_type)->type;
+ goto recur;
+ case BTF_KIND_FUNC_PROTO: {
+ struct btf_param *local_p = btf_params(local_type);
+ struct btf_param *targ_p = btf_params(targ_type);
+ __u16 local_vlen = btf_vlen(local_type);
+ __u16 targ_vlen = btf_vlen(targ_type);
+ int i, err;
+
+ if (local_vlen != targ_vlen)
+ return 0;
+
+ for (i = 0; i < local_vlen; i++, local_p++, targ_p++) {
+ if (level <= 0)
+ return -EINVAL;
+
+ skip_mods_and_typedefs(local_btf, local_p->type, &local_id);
+ skip_mods_and_typedefs(targ_btf, targ_p->type, &targ_id);
+ err = bpf_core_types_are_compat_recur(local_btf, local_id, targ_btf,
+ targ_id, level - 1);
+ if (err <= 0)
+ return err;
+ }
+
+ /* tail recurse for return type check */
+ skip_mods_and_typedefs(local_btf, local_type->type, &local_id);
+ skip_mods_and_typedefs(targ_btf, targ_type->type, &targ_id);
+ goto recur;
+ }
+ default:
+ return 0;
+ }
+}
+
/*
* Turn bpf_core_relo into a low- and high-level spec representation,
* validating correctness along the way, as well as calculating resulting
diff --git a/tools/lib/bpf/relo_core.h b/tools/lib/bpf/relo_core.h
index 7df0da0..b8998f 100644
--- a/tools/lib/bpf/relo_core.h
+++ b/tools/lib/bpf/relo_core.h
@@ -68,6 +68,8 @@ struct bpf_core_relo_res {
__u32 new_type_id;
};
+int bpf_core_types_are_compat_recur(const struct btf *local_btf, __u32 local_id,
+ const struct btf *targ_btf, __u32 targ_id, int level);
int bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id,
const struct btf *targ_btf, __u32 targ_id);
--
2.30.2
