forked from mirrors/linux
		
	bpftool: add ability to dump BTF types
Add new `btf dump` sub-command to bpftool. It allows to dump
human-readable low-level BTF types representation of BTF types. BTF can
be retrieved from few different sources:
  - from BTF object by ID;
  - from PROG, if it has associated BTF;
  - from MAP, if it has associated BTF data; it's possible to narrow
    down types to either key type, value type, both, or all BTF types;
  - from ELF file (.BTF section).
Output format mostly follows BPF verifier log format with few notable
exceptions:
  - all the type/field/param/etc names are enclosed in single quotes to
    allow easier grepping and to stand out a little bit more;
  - FUNC_PROTO output follows STRUCT/UNION/ENUM format of having one
    line per each argument; this is more uniform and allows easy
    grepping, as opposed to succinct, but inconvenient format that BPF
    verifier log is using.
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
			
			
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								tools/bpf/bpftool/btf.c
									
									
									
									
									
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								tools/bpf/bpftool/btf.c
									
									
									
									
									
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							|  | @ -0,0 +1,586 @@ | |||
| // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
 | ||||
| /* Copyright (C) 2019 Facebook */ | ||||
| 
 | ||||
| #include <errno.h> | ||||
| #include <fcntl.h> | ||||
| #include <linux/err.h> | ||||
| #include <stdbool.h> | ||||
| #include <stdio.h> | ||||
| #include <string.h> | ||||
| #include <unistd.h> | ||||
| #include <gelf.h> | ||||
| #include <bpf.h> | ||||
| #include <linux/btf.h> | ||||
| 
 | ||||
| #include "btf.h" | ||||
| #include "json_writer.h" | ||||
| #include "main.h" | ||||
| 
 | ||||
| static const char * const btf_kind_str[NR_BTF_KINDS] = { | ||||
| 	[BTF_KIND_UNKN]		= "UNKNOWN", | ||||
| 	[BTF_KIND_INT]		= "INT", | ||||
| 	[BTF_KIND_PTR]		= "PTR", | ||||
| 	[BTF_KIND_ARRAY]	= "ARRAY", | ||||
| 	[BTF_KIND_STRUCT]	= "STRUCT", | ||||
| 	[BTF_KIND_UNION]	= "UNION", | ||||
| 	[BTF_KIND_ENUM]		= "ENUM", | ||||
| 	[BTF_KIND_FWD]		= "FWD", | ||||
| 	[BTF_KIND_TYPEDEF]	= "TYPEDEF", | ||||
| 	[BTF_KIND_VOLATILE]	= "VOLATILE", | ||||
| 	[BTF_KIND_CONST]	= "CONST", | ||||
| 	[BTF_KIND_RESTRICT]	= "RESTRICT", | ||||
| 	[BTF_KIND_FUNC]		= "FUNC", | ||||
| 	[BTF_KIND_FUNC_PROTO]	= "FUNC_PROTO", | ||||
| 	[BTF_KIND_VAR]		= "VAR", | ||||
| 	[BTF_KIND_DATASEC]	= "DATASEC", | ||||
| }; | ||||
| 
 | ||||
| static const char *btf_int_enc_str(__u8 encoding) | ||||
| { | ||||
| 	switch (encoding) { | ||||
| 	case 0: | ||||
| 		return "(none)"; | ||||
| 	case BTF_INT_SIGNED: | ||||
| 		return "SIGNED"; | ||||
| 	case BTF_INT_CHAR: | ||||
| 		return "CHAR"; | ||||
| 	case BTF_INT_BOOL: | ||||
| 		return "BOOL"; | ||||
| 	default: | ||||
| 		return "UNKN"; | ||||
| 	} | ||||
| } | ||||
| 
 | ||||
| static const char *btf_var_linkage_str(__u32 linkage) | ||||
| { | ||||
| 	switch (linkage) { | ||||
| 	case BTF_VAR_STATIC: | ||||
| 		return "static"; | ||||
| 	case BTF_VAR_GLOBAL_ALLOCATED: | ||||
| 		return "global-alloc"; | ||||
| 	default: | ||||
| 		return "(unknown)"; | ||||
| 	} | ||||
| } | ||||
| 
 | ||||
| static const char *btf_str(const struct btf *btf, __u32 off) | ||||
| { | ||||
| 	if (!off) | ||||
| 		return "(anon)"; | ||||
| 	return btf__name_by_offset(btf, off) ? : "(invalid)"; | ||||
| } | ||||
| 
 | ||||
| static int dump_btf_type(const struct btf *btf, __u32 id, | ||||
| 			 const struct btf_type *t) | ||||
| { | ||||
| 	json_writer_t *w = json_wtr; | ||||
| 	int kind, safe_kind; | ||||
| 
 | ||||
| 	kind = BTF_INFO_KIND(t->info); | ||||
| 	safe_kind = kind <= BTF_KIND_MAX ? kind : BTF_KIND_UNKN; | ||||
| 
 | ||||
| 	if (json_output) { | ||||
| 		jsonw_start_object(w); | ||||
| 		jsonw_uint_field(w, "id", id); | ||||
| 		jsonw_string_field(w, "kind", btf_kind_str[safe_kind]); | ||||
| 		jsonw_string_field(w, "name", btf_str(btf, t->name_off)); | ||||
| 	} else { | ||||
| 		printf("[%u] %s '%s'", id, btf_kind_str[safe_kind], | ||||
| 		       btf_str(btf, t->name_off)); | ||||
| 	} | ||||
| 
 | ||||
| 	switch (BTF_INFO_KIND(t->info)) { | ||||
| 	case BTF_KIND_INT: { | ||||
| 		__u32 v = *(__u32 *)(t + 1); | ||||
| 		const char *enc; | ||||
| 
 | ||||
| 		enc = btf_int_enc_str(BTF_INT_ENCODING(v)); | ||||
| 
 | ||||
| 		if (json_output) { | ||||
| 			jsonw_uint_field(w, "size", t->size); | ||||
| 			jsonw_uint_field(w, "bits_offset", BTF_INT_OFFSET(v)); | ||||
| 			jsonw_uint_field(w, "nr_bits", BTF_INT_BITS(v)); | ||||
| 			jsonw_string_field(w, "encoding", enc); | ||||
| 		} else { | ||||
| 			printf(" size=%u bits_offset=%u nr_bits=%u encoding=%s", | ||||
| 			       t->size, BTF_INT_OFFSET(v), BTF_INT_BITS(v), | ||||
| 			       enc); | ||||
| 		} | ||||
| 		break; | ||||
| 	} | ||||
| 	case BTF_KIND_PTR: | ||||
| 	case BTF_KIND_CONST: | ||||
| 	case BTF_KIND_VOLATILE: | ||||
| 	case BTF_KIND_RESTRICT: | ||||
| 	case BTF_KIND_TYPEDEF: | ||||
| 		if (json_output) | ||||
| 			jsonw_uint_field(w, "type_id", t->type); | ||||
| 		else | ||||
| 			printf(" type_id=%u", t->type); | ||||
| 		break; | ||||
| 	case BTF_KIND_ARRAY: { | ||||
| 		const struct btf_array *arr = (const void *)(t + 1); | ||||
| 
 | ||||
| 		if (json_output) { | ||||
| 			jsonw_uint_field(w, "type_id", arr->type); | ||||
| 			jsonw_uint_field(w, "index_type_id", arr->index_type); | ||||
| 			jsonw_uint_field(w, "nr_elems", arr->nelems); | ||||
| 		} else { | ||||
| 			printf(" type_id=%u index_type_id=%u nr_elems=%u", | ||||
| 			       arr->type, arr->index_type, arr->nelems); | ||||
| 		} | ||||
| 		break; | ||||
| 	} | ||||
| 	case BTF_KIND_STRUCT: | ||||
| 	case BTF_KIND_UNION: { | ||||
| 		const struct btf_member *m = (const void *)(t + 1); | ||||
| 		__u16 vlen = BTF_INFO_VLEN(t->info); | ||||
| 		int i; | ||||
| 
 | ||||
| 		if (json_output) { | ||||
| 			jsonw_uint_field(w, "size", t->size); | ||||
| 			jsonw_uint_field(w, "vlen", vlen); | ||||
| 			jsonw_name(w, "members"); | ||||
| 			jsonw_start_array(w); | ||||
| 		} else { | ||||
| 			printf(" size=%u vlen=%u", t->size, vlen); | ||||
| 		} | ||||
| 		for (i = 0; i < vlen; i++, m++) { | ||||
| 			const char *name = btf_str(btf, m->name_off); | ||||
| 			__u32 bit_off, bit_sz; | ||||
| 
 | ||||
| 			if (BTF_INFO_KFLAG(t->info)) { | ||||
| 				bit_off = BTF_MEMBER_BIT_OFFSET(m->offset); | ||||
| 				bit_sz = BTF_MEMBER_BITFIELD_SIZE(m->offset); | ||||
| 			} else { | ||||
| 				bit_off = m->offset; | ||||
| 				bit_sz = 0; | ||||
| 			} | ||||
| 
 | ||||
| 			if (json_output) { | ||||
| 				jsonw_start_object(w); | ||||
| 				jsonw_string_field(w, "name", name); | ||||
| 				jsonw_uint_field(w, "type_id", m->type); | ||||
| 				jsonw_uint_field(w, "bits_offset", bit_off); | ||||
| 				if (bit_sz) { | ||||
| 					jsonw_uint_field(w, "bitfield_size", | ||||
| 							 bit_sz); | ||||
| 				} | ||||
| 				jsonw_end_object(w); | ||||
| 			} else { | ||||
| 				printf("\n\t'%s' type_id=%u bits_offset=%u", | ||||
| 				       name, m->type, bit_off); | ||||
| 				if (bit_sz) | ||||
| 					printf(" bitfield_size=%u", bit_sz); | ||||
| 			} | ||||
| 		} | ||||
| 		if (json_output) | ||||
| 			jsonw_end_array(w); | ||||
| 		break; | ||||
| 	} | ||||
| 	case BTF_KIND_ENUM: { | ||||
| 		const struct btf_enum *v = (const void *)(t + 1); | ||||
| 		__u16 vlen = BTF_INFO_VLEN(t->info); | ||||
| 		int i; | ||||
| 
 | ||||
| 		if (json_output) { | ||||
| 			jsonw_uint_field(w, "size", t->size); | ||||
| 			jsonw_uint_field(w, "vlen", vlen); | ||||
| 			jsonw_name(w, "values"); | ||||
| 			jsonw_start_array(w); | ||||
| 		} else { | ||||
| 			printf(" size=%u vlen=%u", t->size, vlen); | ||||
| 		} | ||||
| 		for (i = 0; i < vlen; i++, v++) { | ||||
| 			const char *name = btf_str(btf, v->name_off); | ||||
| 
 | ||||
| 			if (json_output) { | ||||
| 				jsonw_start_object(w); | ||||
| 				jsonw_string_field(w, "name", name); | ||||
| 				jsonw_uint_field(w, "val", v->val); | ||||
| 				jsonw_end_object(w); | ||||
| 			} else { | ||||
| 				printf("\n\t'%s' val=%u", name, v->val); | ||||
| 			} | ||||
| 		} | ||||
| 		if (json_output) | ||||
| 			jsonw_end_array(w); | ||||
| 		break; | ||||
| 	} | ||||
| 	case BTF_KIND_FWD: { | ||||
| 		const char *fwd_kind = BTF_INFO_KIND(t->info) ? "union" | ||||
| 							      : "struct"; | ||||
| 
 | ||||
| 		if (json_output) | ||||
| 			jsonw_string_field(w, "fwd_kind", fwd_kind); | ||||
| 		else | ||||
| 			printf(" fwd_kind=%s", fwd_kind); | ||||
| 		break; | ||||
| 	} | ||||
| 	case BTF_KIND_FUNC: | ||||
| 		if (json_output) | ||||
| 			jsonw_uint_field(w, "type_id", t->type); | ||||
| 		else | ||||
| 			printf(" type_id=%u", t->type); | ||||
| 		break; | ||||
| 	case BTF_KIND_FUNC_PROTO: { | ||||
| 		const struct btf_param *p = (const void *)(t + 1); | ||||
| 		__u16 vlen = BTF_INFO_VLEN(t->info); | ||||
| 		int i; | ||||
| 
 | ||||
| 		if (json_output) { | ||||
| 			jsonw_uint_field(w, "ret_type_id", t->type); | ||||
| 			jsonw_uint_field(w, "vlen", vlen); | ||||
| 			jsonw_name(w, "params"); | ||||
| 			jsonw_start_array(w); | ||||
| 		} else { | ||||
| 			printf(" ret_type_id=%u vlen=%u", t->type, vlen); | ||||
| 		} | ||||
| 		for (i = 0; i < vlen; i++, p++) { | ||||
| 			const char *name = btf_str(btf, p->name_off); | ||||
| 
 | ||||
| 			if (json_output) { | ||||
| 				jsonw_start_object(w); | ||||
| 				jsonw_string_field(w, "name", name); | ||||
| 				jsonw_uint_field(w, "type_id", p->type); | ||||
| 				jsonw_end_object(w); | ||||
| 			} else { | ||||
| 				printf("\n\t'%s' type_id=%u", name, p->type); | ||||
| 			} | ||||
| 		} | ||||
| 		if (json_output) | ||||
| 			jsonw_end_array(w); | ||||
| 		break; | ||||
| 	} | ||||
| 	case BTF_KIND_VAR: { | ||||
| 		const struct btf_var *v = (const void *)(t + 1); | ||||
| 		const char *linkage; | ||||
| 
 | ||||
| 		linkage = btf_var_linkage_str(v->linkage); | ||||
| 
 | ||||
| 		if (json_output) { | ||||
| 			jsonw_uint_field(w, "type_id", t->type); | ||||
| 			jsonw_string_field(w, "linkage", linkage); | ||||
| 		} else { | ||||
| 			printf(" type_id=%u, linkage=%s", t->type, linkage); | ||||
| 		} | ||||
| 		break; | ||||
| 	} | ||||
| 	case BTF_KIND_DATASEC: { | ||||
| 		const struct btf_var_secinfo *v = (const void *)(t+1); | ||||
| 		__u16 vlen = BTF_INFO_VLEN(t->info); | ||||
| 		int i; | ||||
| 
 | ||||
| 		if (json_output) { | ||||
| 			jsonw_uint_field(w, "size", t->size); | ||||
| 			jsonw_uint_field(w, "vlen", vlen); | ||||
| 			jsonw_name(w, "vars"); | ||||
| 			jsonw_start_array(w); | ||||
| 		} else { | ||||
| 			printf(" size=%u vlen=%u", t->size, vlen); | ||||
| 		} | ||||
| 		for (i = 0; i < vlen; i++, v++) { | ||||
| 			if (json_output) { | ||||
| 				jsonw_start_object(w); | ||||
| 				jsonw_uint_field(w, "type_id", v->type); | ||||
| 				jsonw_uint_field(w, "offset", v->offset); | ||||
| 				jsonw_uint_field(w, "size", v->size); | ||||
| 				jsonw_end_object(w); | ||||
| 			} else { | ||||
| 				printf("\n\ttype_id=%u offset=%u size=%u", | ||||
| 				       v->type, v->offset, v->size); | ||||
| 			} | ||||
| 		} | ||||
| 		if (json_output) | ||||
| 			jsonw_end_array(w); | ||||
| 		break; | ||||
| 	} | ||||
| 	default: | ||||
| 		break; | ||||
| 	} | ||||
| 
 | ||||
| 	if (json_output) | ||||
| 		jsonw_end_object(json_wtr); | ||||
| 	else | ||||
| 		printf("\n"); | ||||
| 
 | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| static int dump_btf_raw(const struct btf *btf, | ||||
| 			__u32 *root_type_ids, int root_type_cnt) | ||||
| { | ||||
| 	const struct btf_type *t; | ||||
| 	int i; | ||||
| 
 | ||||
| 	if (json_output) { | ||||
| 		jsonw_start_object(json_wtr); | ||||
| 		jsonw_name(json_wtr, "types"); | ||||
| 		jsonw_start_array(json_wtr); | ||||
| 	} | ||||
| 
 | ||||
| 	if (root_type_cnt) { | ||||
| 		for (i = 0; i < root_type_cnt; i++) { | ||||
| 			t = btf__type_by_id(btf, root_type_ids[i]); | ||||
| 			dump_btf_type(btf, root_type_ids[i], t); | ||||
| 		} | ||||
| 	} else { | ||||
| 		int cnt = btf__get_nr_types(btf); | ||||
| 
 | ||||
| 		for (i = 1; i <= cnt; i++) { | ||||
| 			t = btf__type_by_id(btf, i); | ||||
| 			dump_btf_type(btf, i, t); | ||||
| 		} | ||||
| 	} | ||||
| 
 | ||||
| 	if (json_output) { | ||||
| 		jsonw_end_array(json_wtr); | ||||
| 		jsonw_end_object(json_wtr); | ||||
| 	} | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| static bool check_btf_endianness(GElf_Ehdr *ehdr) | ||||
| { | ||||
| 	static unsigned int const endian = 1; | ||||
| 
 | ||||
| 	switch (ehdr->e_ident[EI_DATA]) { | ||||
| 	case ELFDATA2LSB: | ||||
| 		return *(unsigned char const *)&endian == 1; | ||||
| 	case ELFDATA2MSB: | ||||
| 		return *(unsigned char const *)&endian == 0; | ||||
| 	default: | ||||
| 		return 0; | ||||
| 	} | ||||
| } | ||||
| 
 | ||||
| static int btf_load_from_elf(const char *path, struct btf **btf) | ||||
| { | ||||
| 	int err = -1, fd = -1, idx = 0; | ||||
| 	Elf_Data *btf_data = NULL; | ||||
| 	Elf_Scn *scn = NULL; | ||||
| 	Elf *elf = NULL; | ||||
| 	GElf_Ehdr ehdr; | ||||
| 
 | ||||
| 	if (elf_version(EV_CURRENT) == EV_NONE) { | ||||
| 		p_err("failed to init libelf for %s", path); | ||||
| 		return -1; | ||||
| 	} | ||||
| 
 | ||||
| 	fd = open(path, O_RDONLY); | ||||
| 	if (fd < 0) { | ||||
| 		p_err("failed to open %s: %s", path, strerror(errno)); | ||||
| 		return -1; | ||||
| 	} | ||||
| 
 | ||||
| 	elf = elf_begin(fd, ELF_C_READ, NULL); | ||||
| 	if (!elf) { | ||||
| 		p_err("failed to open %s as ELF file", path); | ||||
| 		goto done; | ||||
| 	} | ||||
| 	if (!gelf_getehdr(elf, &ehdr)) { | ||||
| 		p_err("failed to get EHDR from %s", path); | ||||
| 		goto done; | ||||
| 	} | ||||
| 	if (!check_btf_endianness(&ehdr)) { | ||||
| 		p_err("non-native ELF endianness is not supported"); | ||||
| 		goto done; | ||||
| 	} | ||||
| 	if (!elf_rawdata(elf_getscn(elf, ehdr.e_shstrndx), NULL)) { | ||||
| 		p_err("failed to get e_shstrndx from %s\n", path); | ||||
| 		goto done; | ||||
| 	} | ||||
| 
 | ||||
| 	while ((scn = elf_nextscn(elf, scn)) != NULL) { | ||||
| 		GElf_Shdr sh; | ||||
| 		char *name; | ||||
| 
 | ||||
| 		idx++; | ||||
| 		if (gelf_getshdr(scn, &sh) != &sh) { | ||||
| 			p_err("failed to get section(%d) header from %s", | ||||
| 			      idx, path); | ||||
| 			goto done; | ||||
| 		} | ||||
| 		name = elf_strptr(elf, ehdr.e_shstrndx, sh.sh_name); | ||||
| 		if (!name) { | ||||
| 			p_err("failed to get section(%d) name from %s", | ||||
| 			      idx, path); | ||||
| 			goto done; | ||||
| 		} | ||||
| 		if (strcmp(name, BTF_ELF_SEC) == 0) { | ||||
| 			btf_data = elf_getdata(scn, 0); | ||||
| 			if (!btf_data) { | ||||
| 				p_err("failed to get section(%d, %s) data from %s", | ||||
| 				      idx, name, path); | ||||
| 				goto done; | ||||
| 			} | ||||
| 			break; | ||||
| 		} | ||||
| 	} | ||||
| 
 | ||||
| 	if (!btf_data) { | ||||
| 		p_err("%s ELF section not found in %s", BTF_ELF_SEC, path); | ||||
| 		goto done; | ||||
| 	} | ||||
| 
 | ||||
| 	*btf = btf__new(btf_data->d_buf, btf_data->d_size); | ||||
| 	if (IS_ERR(*btf)) { | ||||
| 		err = PTR_ERR(*btf); | ||||
| 		*btf = NULL; | ||||
| 		p_err("failed to load BTF data from %s: %s", | ||||
| 		      path, strerror(err)); | ||||
| 		goto done; | ||||
| 	} | ||||
| 
 | ||||
| 	err = 0; | ||||
| done: | ||||
| 	if (err) { | ||||
| 		if (*btf) { | ||||
| 			btf__free(*btf); | ||||
| 			*btf = NULL; | ||||
| 		} | ||||
| 	} | ||||
| 	if (elf) | ||||
| 		elf_end(elf); | ||||
| 	close(fd); | ||||
| 	return err; | ||||
| } | ||||
| 
 | ||||
| static int do_dump(int argc, char **argv) | ||||
| { | ||||
| 	struct btf *btf = NULL; | ||||
| 	__u32 root_type_ids[2]; | ||||
| 	int root_type_cnt = 0; | ||||
| 	__u32 btf_id = -1; | ||||
| 	const char *src; | ||||
| 	int fd = -1; | ||||
| 	int err; | ||||
| 
 | ||||
| 	if (!REQ_ARGS(2)) { | ||||
| 		usage(); | ||||
| 		return -1; | ||||
| 	} | ||||
| 	src = GET_ARG(); | ||||
| 
 | ||||
| 	if (is_prefix(src, "map")) { | ||||
| 		struct bpf_map_info info = {}; | ||||
| 		__u32 len = sizeof(info); | ||||
| 
 | ||||
| 		if (!REQ_ARGS(2)) { | ||||
| 			usage(); | ||||
| 			return -1; | ||||
| 		} | ||||
| 
 | ||||
| 		fd = map_parse_fd_and_info(&argc, &argv, &info, &len); | ||||
| 		if (fd < 0) | ||||
| 			return -1; | ||||
| 
 | ||||
| 		btf_id = info.btf_id; | ||||
| 		if (argc && is_prefix(*argv, "key")) { | ||||
| 			root_type_ids[root_type_cnt++] = info.btf_key_type_id; | ||||
| 			NEXT_ARG(); | ||||
| 		} else if (argc && is_prefix(*argv, "value")) { | ||||
| 			root_type_ids[root_type_cnt++] = info.btf_value_type_id; | ||||
| 			NEXT_ARG(); | ||||
| 		} else if (argc && is_prefix(*argv, "all")) { | ||||
| 			NEXT_ARG(); | ||||
| 		} else if (argc && is_prefix(*argv, "kv")) { | ||||
| 			root_type_ids[root_type_cnt++] = info.btf_key_type_id; | ||||
| 			root_type_ids[root_type_cnt++] = info.btf_value_type_id; | ||||
| 			NEXT_ARG(); | ||||
| 		} else { | ||||
| 			root_type_ids[root_type_cnt++] = info.btf_key_type_id; | ||||
| 			root_type_ids[root_type_cnt++] = info.btf_value_type_id; | ||||
| 		} | ||||
| 	} else if (is_prefix(src, "prog")) { | ||||
| 		struct bpf_prog_info info = {}; | ||||
| 		__u32 len = sizeof(info); | ||||
| 
 | ||||
| 		if (!REQ_ARGS(2)) { | ||||
| 			usage(); | ||||
| 			return -1; | ||||
| 		} | ||||
| 
 | ||||
| 		fd = prog_parse_fd(&argc, &argv); | ||||
| 		if (fd < 0) | ||||
| 			return -1; | ||||
| 
 | ||||
| 		err = bpf_obj_get_info_by_fd(fd, &info, &len); | ||||
| 		if (err) { | ||||
| 			p_err("can't get prog info: %s", strerror(errno)); | ||||
| 			goto done; | ||||
| 		} | ||||
| 
 | ||||
| 		btf_id = info.btf_id; | ||||
| 	} else if (is_prefix(src, "id")) { | ||||
| 		char *endptr; | ||||
| 
 | ||||
| 		btf_id = strtoul(*argv, &endptr, 0); | ||||
| 		if (*endptr) { | ||||
| 			p_err("can't parse %s as ID", **argv); | ||||
| 			return -1; | ||||
| 		} | ||||
| 		NEXT_ARG(); | ||||
| 	} else if (is_prefix(src, "file")) { | ||||
| 		err = btf_load_from_elf(*argv, &btf); | ||||
| 		if (err) | ||||
| 			goto done; | ||||
| 		NEXT_ARG(); | ||||
| 	} else { | ||||
| 		err = -1; | ||||
| 		p_err("unrecognized BTF source specifier: '%s'", src); | ||||
| 		goto done; | ||||
| 	} | ||||
| 
 | ||||
| 	if (!btf) { | ||||
| 		err = btf__get_from_id(btf_id, &btf); | ||||
| 		if (err) { | ||||
| 			p_err("get btf by id (%u): %s", btf_id, strerror(err)); | ||||
| 			goto done; | ||||
| 		} | ||||
| 		if (!btf) { | ||||
| 			err = ENOENT; | ||||
| 			p_err("can't find btf with ID (%u)", btf_id); | ||||
| 			goto done; | ||||
| 		} | ||||
| 	} | ||||
| 
 | ||||
| 	dump_btf_raw(btf, root_type_ids, root_type_cnt); | ||||
| 
 | ||||
| done: | ||||
| 	close(fd); | ||||
| 	btf__free(btf); | ||||
| 	return err; | ||||
| } | ||||
| 
 | ||||
| static int do_help(int argc, char **argv) | ||||
| { | ||||
| 	if (json_output) { | ||||
| 		jsonw_null(json_wtr); | ||||
| 		return 0; | ||||
| 	} | ||||
| 
 | ||||
| 	fprintf(stderr, | ||||
| 		"Usage: %s btf dump BTF_SRC\n" | ||||
| 		"       %s btf help\n" | ||||
| 		"\n" | ||||
| 		"       BTF_SRC := { id BTF_ID | prog PROG | map MAP [{key | value | kv | all}] | file FILE }\n" | ||||
| 		"       " HELP_SPEC_MAP "\n" | ||||
| 		"       " HELP_SPEC_PROGRAM "\n" | ||||
| 		"       " HELP_SPEC_OPTIONS "\n" | ||||
| 		"", | ||||
| 		bin_name, bin_name); | ||||
| 
 | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| static const struct cmd cmds[] = { | ||||
| 	{ "help",	do_help }, | ||||
| 	{ "dump",	do_dump }, | ||||
| 	{ 0 } | ||||
| }; | ||||
| 
 | ||||
| int do_btf(int argc, char **argv) | ||||
| { | ||||
| 	return cmd_select(cmds, argc, argv, do_help); | ||||
| } | ||||
|  | @ -56,7 +56,7 @@ static int do_help(int argc, char **argv) | |||
| 		"       %s batch file FILE\n" | ||||
| 		"       %s version\n" | ||||
| 		"\n" | ||||
| 		"       OBJECT := { prog | map | cgroup | perf | net | feature }\n" | ||||
| 		"       OBJECT := { prog | map | cgroup | perf | net | feature | btf }\n" | ||||
| 		"       " HELP_SPEC_OPTIONS "\n" | ||||
| 		"", | ||||
| 		bin_name, bin_name, bin_name); | ||||
|  | @ -188,6 +188,7 @@ static const struct cmd cmds[] = { | |||
| 	{ "perf",	do_perf }, | ||||
| 	{ "net",	do_net }, | ||||
| 	{ "feature",	do_feature }, | ||||
| 	{ "btf",	do_btf }, | ||||
| 	{ "version",	do_version }, | ||||
| 	{ 0 } | ||||
| }; | ||||
|  |  | |||
|  | @ -150,6 +150,7 @@ int do_perf(int argc, char **arg); | |||
| int do_net(int argc, char **arg); | ||||
| int do_tracelog(int argc, char **arg); | ||||
| int do_feature(int argc, char **argv); | ||||
| int do_btf(int argc, char **argv); | ||||
| 
 | ||||
| int parse_u32_arg(int *argc, char ***argv, __u32 *val, const char *what); | ||||
| int prog_parse_fd(int *argc, char ***argv); | ||||
|  |  | |||
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		Reference in a new issue
	
	 Andrii Nakryiko
						Andrii Nakryiko