27 	/* high-level spec: named fields and array indices only */
28 	struct bpf_core_accessor spec[BPF_CORE_SPEC_MAX_LEN];  member
33 	/* high-level spec length */
35 	/* raw, low-level spec: 1-to-1 with accessor spec string */
37 	/* raw spec length */
39 	/* field bit offset represented by spec */
117  * Turn bpf_core_relo into a low- and high-level spec representation,
119  * field bit offset, specified by accessor string. Low-level spec captures
138  * Low-level spec has 1:1 mapping with each element of access string (it's
141  * High-level spec will capture only 3 points:
143  *   - field 'a' access (corresponds to '2' in low-level spec);
144  *   - array element #3 access (corresponds to '3' in low-level spec).
148  * spec and raw_spec are kept empty.
157 			       struct bpf_core_spec *spec)  in bpf_core_parse_spec()  argument
169 	memset(spec, 0, sizeof(*spec));  in bpf_core_parse_spec()
170 	spec->btf = btf;  in bpf_core_parse_spec()
171 	spec->root_type_id = type_id;  in bpf_core_parse_spec()
172 	spec->relo_kind = relo_kind;  in bpf_core_parse_spec()
187 		if (spec->raw_len == BPF_CORE_SPEC_MAX_LEN)  in bpf_core_parse_spec()
190 		spec->raw_spec[spec->raw_len++] = access_idx;  in bpf_core_parse_spec()
193 	if (spec->raw_len == 0)  in bpf_core_parse_spec()
200 	access_idx = spec->raw_spec[0];  in bpf_core_parse_spec()
201 	acc = &spec->spec[0];  in bpf_core_parse_spec()
204 	spec->len++;  in bpf_core_parse_spec()
207 		if (!btf_is_enum(t) || spec->raw_len > 1 || access_idx >= btf_vlen(t))  in bpf_core_parse_spec()
221 	spec->bit_offset = access_idx * sz * 8;  in bpf_core_parse_spec()
223 	for (i = 1; i < spec->raw_len; i++) {  in bpf_core_parse_spec()
228 		access_idx = spec->raw_spec[i];  in bpf_core_parse_spec()
229 		acc = &spec->spec[spec->len];  in bpf_core_parse_spec()
239 			spec->bit_offset += bit_offset;  in bpf_core_parse_spec()
250 				spec->len++;  in bpf_core_parse_spec()
266 			spec->spec[spec->len].type_id = id;  in bpf_core_parse_spec()
267 			spec->spec[spec->len].idx = access_idx;  in bpf_core_parse_spec()
268 			spec->len++;  in bpf_core_parse_spec()
273 			spec->bit_offset += access_idx * sz * 8;  in bpf_core_parse_spec()
358  * maintain low-level spec for target as well. Also keep updating target
375 				 struct bpf_core_spec *spec,  in bpf_core_match_member()  argument
403 		if (spec->raw_len == BPF_CORE_SPEC_MAX_LEN)  in bpf_core_match_member()
407 		spec->bit_offset += bit_offset;  in bpf_core_match_member()
408 		spec->raw_spec[spec->raw_len++] = i;  in bpf_core_match_member()
415 						      spec, next_targ_id);  in bpf_core_match_member()
422 			targ_acc = &spec->spec[spec->len++];  in bpf_core_match_member()
432 				spec->len--; /* pop accessor */  in bpf_core_match_member()
436 		spec->bit_offset -= bit_offset;  in bpf_core_match_member()
437 		spec->raw_len--;  in bpf_core_match_member()
444  * Try to match local spec to a target type and, if successful, produce full
445  * target spec (high-level, low-level + bit offset).
467 	local_acc = &local_spec->spec[0];  in bpf_core_spec_match()
468 	targ_acc = &targ_spec->spec[0];  in bpf_core_spec_match()
560 				    const struct bpf_core_spec *spec,  in bpf_core_calc_field_relo()  argument
575 		*val = spec ? 1 : 0;  in bpf_core_calc_field_relo()
579 	if (!spec)  in bpf_core_calc_field_relo()
582 	acc = &spec->spec[spec->len - 1];  in bpf_core_calc_field_relo()
583 	t = btf__type_by_id(spec->btf, acc->type_id);  in bpf_core_calc_field_relo()
588 			*val = spec->bit_offset / 8;  in bpf_core_calc_field_relo()
590 			sz = btf__resolve_size(spec->btf, acc->type_id);  in bpf_core_calc_field_relo()
596 			sz = btf__resolve_size(spec->btf, acc->type_id);  in bpf_core_calc_field_relo()
611 	mt = skip_mods_and_typedefs(spec->btf, m->type, &field_type_id);  in bpf_core_calc_field_relo()
612 	bit_off = spec->bit_offset;  in bpf_core_calc_field_relo()
631 		sz = btf__resolve_size(spec->btf, field_type_id);  in bpf_core_calc_field_relo()
635 		byte_off = spec->bit_offset / 8;  in bpf_core_calc_field_relo()
685 				   const struct bpf_core_spec *spec,  in bpf_core_calc_type_relo()  argument
691 	if (!spec) {  in bpf_core_calc_type_relo()
698 		*val = spec->root_type_id;  in bpf_core_calc_type_relo()
704 		sz = btf__resolve_size(spec->btf, spec->root_type_id);  in bpf_core_calc_type_relo()
719 				      const struct bpf_core_spec *spec,  in bpf_core_calc_enumval_relo()  argument
727 		*val = spec ? 1 : 0;  in bpf_core_calc_enumval_relo()
730 		if (!spec)  in bpf_core_calc_enumval_relo()
732 		t = btf__type_by_id(spec->btf, spec->spec[0].type_id);  in bpf_core_calc_enumval_relo()
733 		e = btf_enum(t) + spec->spec[0].idx;  in bpf_core_calc_enumval_relo()
906  * For existence relocations target spec will be NULL if field/type is not found.
908  * spec, and is checked before patching instruction. If actual insn->imm value
1044 /* Output spec definition in the format:
1045  * [<type-id>] (<type-name>) + <raw-spec> => <offset>@<spec>,
1046  * where <spec> is a C-syntax view of recorded field access, e.g.: x.a[3].b
1048 static void bpf_core_dump_spec(int level, const struct bpf_core_spec *spec)  in bpf_core_dump_spec()  argument
1056 	type_id = spec->root_type_id;  in bpf_core_dump_spec()
1057 	t = btf__type_by_id(spec->btf, type_id);  in bpf_core_dump_spec()
1058 	s = btf__name_by_offset(spec->btf, t->name_off);  in bpf_core_dump_spec()
1062 	if (core_relo_is_type_based(spec->relo_kind))  in bpf_core_dump_spec()
1065 	if (core_relo_is_enumval_based(spec->relo_kind)) {  in bpf_core_dump_spec()
1066 		t = skip_mods_and_typedefs(spec->btf, type_id, NULL);  in bpf_core_dump_spec()
1067 		e = btf_enum(t) + spec->raw_spec[0];  in bpf_core_dump_spec()
1068 		s = btf__name_by_offset(spec->btf, e->name_off);  in bpf_core_dump_spec()
1074 	if (core_relo_is_field_based(spec->relo_kind)) {  in bpf_core_dump_spec()
1075 		for (i = 0; i < spec->len; i++) {  in bpf_core_dump_spec()
1076 			if (spec->spec[i].name)  in bpf_core_dump_spec()
1077 				libbpf_print(level, ".%s", spec->spec[i].name);  in bpf_core_dump_spec()
1078 			else if (i > 0 || spec->spec[i].idx > 0)  in bpf_core_dump_spec()
1079 				libbpf_print(level, "[%u]", spec->spec[i].idx);  in bpf_core_dump_spec()
1083 		for (i = 0; i < spec->raw_len; i++)  in bpf_core_dump_spec()
1084 			libbpf_print(level, "%s%d", i == 0 ? "" : ":", spec->raw_spec[i]);  in bpf_core_dump_spec()
1086 		if (spec->bit_offset % 8)  in bpf_core_dump_spec()
1088 				     spec->bit_offset / 8, spec->bit_offset % 8);  in bpf_core_dump_spec()
1090 			libbpf_print(level, " @ offset %u)", spec->bit_offset / 8);  in bpf_core_dump_spec()
1121  *    high-level spec accessors, meaning that all named fields should match,
1125  *    matching the spec. As long as all the specs resolve to the same set of
1182 	pr_debug("prog '%s': relo #%d: kind <%s> (%d), spec is ", prog_name,  in bpf_core_apply_relo_insn()