bpf: Add type_id pointer as argument to __btf_resolve_size

Adding type_id pointer as argument to __btf_resolve_size
to return also BTF ID of the resolved type. It will be
used in following changes.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200825192124.710397-6-jolsa@kernel.org
This commit is contained in:
Jiri Olsa 2020-08-25 21:21:15 +02:00 committed by Alexei Starovoitov
parent 69ff304792
commit 887c31a39c

View File

@ -1082,6 +1082,7 @@ static const struct resolve_vertex *env_stack_peak(struct btf_verifier_env *env)
* *elem_id: id of u32
* *total_nelems: (x * y). Hence, individual elem size is
* (*type_size / *total_nelems)
* *type_id: id of type if it's changed within the function, 0 if not
*
* type: is not an array (e.g. const struct X)
* return type: type "struct X"
@ -1089,15 +1090,16 @@ static const struct resolve_vertex *env_stack_peak(struct btf_verifier_env *env)
* *elem_type: same as return type ("struct X")
* *elem_id: 0
* *total_nelems: 1
* *type_id: id of type if it's changed within the function, 0 if not
*/
static const struct btf_type *
__btf_resolve_size(const struct btf *btf, const struct btf_type *type,
u32 *type_size, const struct btf_type **elem_type,
u32 *elem_id, u32 *total_nelems)
u32 *elem_id, u32 *total_nelems, u32 *type_id)
{
const struct btf_type *array_type = NULL;
const struct btf_array *array = NULL;
u32 i, size, nelems = 1;
u32 i, size, nelems = 1, id = 0;
for (i = 0; i < MAX_RESOLVE_DEPTH; i++) {
switch (BTF_INFO_KIND(type->info)) {
@ -1118,6 +1120,7 @@ __btf_resolve_size(const struct btf *btf, const struct btf_type *type,
case BTF_KIND_VOLATILE:
case BTF_KIND_CONST:
case BTF_KIND_RESTRICT:
id = type->type;
type = btf_type_by_id(btf, type->type);
break;
@ -1150,6 +1153,8 @@ __btf_resolve_size(const struct btf *btf, const struct btf_type *type,
*elem_type = type;
if (elem_id)
*elem_id = array ? array->type : 0;
if (type_id && id)
*type_id = id;
return array_type ? : type;
}
@ -1158,7 +1163,7 @@ const struct btf_type *
btf_resolve_size(const struct btf *btf, const struct btf_type *type,
u32 *type_size)
{
return __btf_resolve_size(btf, type, type_size, NULL, NULL);
return __btf_resolve_size(btf, type, type_size, NULL, NULL, NULL, NULL);
}
/* The input param "type_id" must point to a needs_resolve type */
@ -3988,7 +3993,7 @@ int btf_struct_access(struct bpf_verifier_log *log,
mname = __btf_name_by_offset(btf_vmlinux, member->name_off);
mtype = __btf_resolve_size(btf_vmlinux, mtype, &msize,
&elem_type, NULL, &total_nelems);
&elem_type, NULL, &total_nelems, NULL);
if (IS_ERR(mtype)) {
bpf_log(log, "field %s doesn't have size\n", mname);
return -EFAULT;