diff options
| -rw-r--r-- | tools/bpf/bpftool/Documentation/bpftool-btf.rst | 7 | ||||
| -rw-r--r-- | tools/bpf/bpftool/bash-completion/bpftool | 20 | ||||
| -rw-r--r-- | tools/bpf/bpftool/btf.c | 342 |
3 files changed, 363 insertions, 6 deletions
diff --git a/tools/bpf/bpftool/Documentation/bpftool-btf.rst b/tools/bpf/bpftool/Documentation/bpftool-btf.rst index 6694a0fc8f99..39615f8e145b 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-btf.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-btf.rst @@ -19,6 +19,7 @@ SYNOPSIS BTF COMMANDS ============= +| **bpftool** **btf** { **show** | **list** } [**id** *BTF_ID*] | **bpftool** **btf dump** *BTF_SRC* [**format** *FORMAT*] | **bpftool** **btf help** | @@ -29,6 +30,12 @@ BTF COMMANDS DESCRIPTION =========== + **bpftool btf { show | list }** [**id** *BTF_ID*] + Show information about loaded BTF objects. If a BTF ID is + specified, show information only about given BTF object, + otherwise list all BTF objects currently loaded on the + system. + **bpftool btf dump** *BTF_SRC* Dump BTF entries from a given *BTF_SRC*. diff --git a/tools/bpf/bpftool/bash-completion/bpftool b/tools/bpf/bpftool/bash-completion/bpftool index 4549fd424069..2ffd351f9dbf 100644 --- a/tools/bpf/bpftool/bash-completion/bpftool +++ b/tools/bpf/bpftool/bash-completion/bpftool @@ -73,8 +73,8 @@ _bpftool_get_prog_tags() _bpftool_get_btf_ids() { - COMPREPLY+=( $( compgen -W "$( bpftool -jp prog 2>&1 | \ - command sed -n 's/.*"btf_id": \(.*\),\?$/\1/p' )" -- "$cur" ) ) + COMPREPLY+=( $( compgen -W "$( bpftool -jp btf 2>&1 | \ + command sed -n 's/.*"id": \(.*\),$/\1/p' )" -- "$cur" ) ) } _bpftool_get_obj_map_names() @@ -670,7 +670,7 @@ _bpftool() map) _bpftool_get_map_ids ;; - dump) + $command) _bpftool_get_btf_ids ;; esac @@ -698,9 +698,21 @@ _bpftool() ;; esac ;; + show|list) + case $prev in + $command) + COMPREPLY+=( $( compgen -W "id" -- "$cur" ) ) + ;; + id) + _bpftool_get_btf_ids + ;; + esac + return 0 + ;; *) [[ $prev == $object ]] && \ - COMPREPLY=( $( compgen -W 'dump help' -- "$cur" ) ) + COMPREPLY=( $( compgen -W 'dump help show list' \ + -- "$cur" ) ) ;; esac ;; diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c index 8805637f1a7e..9a9376d1d3df 100644 --- a/tools/bpf/bpftool/btf.c +++ b/tools/bpf/bpftool/btf.c @@ -11,6 +11,7 @@ #include <bpf.h> #include <libbpf.h> #include <linux/btf.h> +#include <linux/hashtable.h> #include "btf.h" #include "json_writer.h" @@ -35,6 +36,16 @@ static const char * const btf_kind_str[NR_BTF_KINDS] = { [BTF_KIND_DATASEC] = "DATASEC", }; +struct btf_attach_table { + DECLARE_HASHTABLE(table, 16); +}; + +struct btf_attach_point { + __u32 obj_id; + __u32 btf_id; + struct hlist_node hash; +}; + static const char *btf_int_enc_str(__u8 encoding) { switch (encoding) { @@ -522,6 +533,330 @@ done: return err; } +static int btf_parse_fd(int *argc, char ***argv) +{ + unsigned int id; + char *endptr; + int fd; + + if (!is_prefix(*argv[0], "id")) { + p_err("expected 'id', got: '%s'?", **argv); + return -1; + } + NEXT_ARGP(); + + id = strtoul(**argv, &endptr, 0); + if (*endptr) { + p_err("can't parse %s as ID", **argv); + return -1; + } + NEXT_ARGP(); + + fd = bpf_btf_get_fd_by_id(id); + if (fd < 0) + p_err("can't get BTF object by id (%u): %s", + id, strerror(errno)); + + return fd; +} + +static void delete_btf_table(struct btf_attach_table *tab) +{ + struct btf_attach_point *obj; + struct hlist_node *tmp; + + unsigned int bkt; + + hash_for_each_safe(tab->table, bkt, tmp, obj, hash) { + hash_del(&obj->hash); + free(obj); + } +} + +static int +build_btf_type_table(struct btf_attach_table *tab, enum bpf_obj_type type, + void *info, __u32 *len) +{ + static const char * const names[] = { + [BPF_OBJ_UNKNOWN] = "unknown", + [BPF_OBJ_PROG] = "prog", + [BPF_OBJ_MAP] = "map", + }; + struct btf_attach_point *obj_node; + __u32 btf_id, id = 0; + int err; + int fd; + + while (true) { + switch (type) { + case BPF_OBJ_PROG: + err = bpf_prog_get_next_id(id, &id); + break; + case BPF_OBJ_MAP: + err = bpf_map_get_next_id(id, &id); + break; + default: + err = -1; + p_err("unexpected object type: %d", type); + goto err_free; + } + if (err) { + if (errno == ENOENT) { + err = 0; + break; + } + p_err("can't get next %s: %s%s", names[type], + strerror(errno), + errno == EINVAL ? " -- kernel too old?" : ""); + goto err_free; + } + + switch (type) { + case BPF_OBJ_PROG: + fd = bpf_prog_get_fd_by_id(id); + break; + case BPF_OBJ_MAP: + fd = bpf_map_get_fd_by_id(id); + break; + default: + err = -1; + p_err("unexpected object type: %d", type); + goto err_free; + } + if (fd < 0) { + if (errno == ENOENT) + continue; + p_err("can't get %s by id (%u): %s", names[type], id, + strerror(errno)); + err = -1; + goto err_free; + } + + memset(info, 0, *len); + err = bpf_obj_get_info_by_fd(fd, info, len); + close(fd); + if (err) { + p_err("can't get %s info: %s", names[type], + strerror(errno)); + goto err_free; + } + + switch (type) { + case BPF_OBJ_PROG: + btf_id = ((struct bpf_prog_info *)info)->btf_id; + break; + case BPF_OBJ_MAP: + btf_id = ((struct bpf_map_info *)info)->btf_id; + break; + default: + err = -1; + p_err("unexpected object type: %d", type); + goto err_free; + } + if (!btf_id) + continue; + + obj_node = calloc(1, sizeof(*obj_node)); + if (!obj_node) { + p_err("failed to allocate memory: %s", strerror(errno)); + goto err_free; + } + + obj_node->obj_id = id; + obj_node->btf_id = btf_id; + hash_add(tab->table, &obj_node->hash, obj_node->btf_id); + } + + return 0; + +err_free: + delete_btf_table(tab); + return err; +} + +static int +build_btf_tables(struct btf_attach_table *btf_prog_table, + struct btf_attach_table *btf_map_table) +{ + struct bpf_prog_info prog_info; + __u32 prog_len = sizeof(prog_info); + struct bpf_map_info map_info; + __u32 map_len = sizeof(map_info); + int err = 0; + + err = build_btf_type_table(btf_prog_table, BPF_OBJ_PROG, &prog_info, + &prog_len); + if (err) + return err; + + err = build_btf_type_table(btf_map_table, BPF_OBJ_MAP, &map_info, + &map_len); + if (err) { + delete_btf_table(btf_prog_table); + return err; + } + + return 0; +} + +static void +show_btf_plain(struct bpf_btf_info *info, int fd, + struct btf_attach_table *btf_prog_table, + struct btf_attach_table *btf_map_table) +{ + struct btf_attach_point *obj; + int n; + + printf("%u: ", info->id); + printf("size %uB", info->btf_size); + + n = 0; + hash_for_each_possible(btf_prog_table->table, obj, hash, info->id) { + if (obj->btf_id == info->id) + printf("%s%u", n++ == 0 ? " prog_ids " : ",", + obj->obj_id); + } + + n = 0; + hash_for_each_possible(btf_map_table->table, obj, hash, info->id) { + if (obj->btf_id == info->id) + printf("%s%u", n++ == 0 ? " map_ids " : ",", + obj->obj_id); + } + + printf("\n"); +} + +static void +show_btf_json(struct bpf_btf_info *info, int fd, + struct btf_attach_table *btf_prog_table, + struct btf_attach_table *btf_map_table) +{ + struct btf_attach_point *obj; + + jsonw_start_object(json_wtr); /* btf object */ + jsonw_uint_field(json_wtr, "id", info->id); + jsonw_uint_field(json_wtr, "size", info->btf_size); + + jsonw_name(json_wtr, "prog_ids"); + jsonw_start_array(json_wtr); /* prog_ids */ + hash_for_each_possible(btf_prog_table->table, obj, hash, + info->id) { + if (obj->btf_id == info->id) + jsonw_uint(json_wtr, obj->obj_id); + } + jsonw_end_array(json_wtr); /* prog_ids */ + + jsonw_name(json_wtr, "map_ids"); + jsonw_start_array(json_wtr); /* map_ids */ + hash_for_each_possible(btf_map_table->table, obj, hash, + info->id) { + if (obj->btf_id == info->id) + jsonw_uint(json_wtr, obj->obj_id); + } + jsonw_end_array(json_wtr); /* map_ids */ + jsonw_end_object(json_wtr); /* btf object */ +} + +static int +show_btf(int fd, struct btf_attach_table *btf_prog_table, + struct btf_attach_table *btf_map_table) +{ + struct bpf_btf_info info = {}; + __u32 len = sizeof(info); + int err; + + err = bpf_obj_get_info_by_fd(fd, &info, &len); + if (err) { + p_err("can't get BTF object info: %s", strerror(errno)); + return -1; + } + + if (json_output) + show_btf_json(&info, fd, btf_prog_table, btf_map_table); + else + show_btf_plain(&info, fd, btf_prog_table, btf_map_table); + + return 0; +} + +static int do_show(int argc, char **argv) +{ + struct btf_attach_table btf_prog_table; + struct btf_attach_table btf_map_table; + int err, fd = -1; + __u32 id = 0; + + if (argc == 2) { + fd = btf_parse_fd(&argc, &argv); + if (fd < 0) + return -1; + } + + if (argc) { + if (fd >= 0) + close(fd); + return BAD_ARG(); + } + + hash_init(btf_prog_table.table); + hash_init(btf_map_table.table); + err = build_btf_tables(&btf_prog_table, &btf_map_table); + if (err) { + if (fd >= 0) + close(fd); + return err; + } + + if (fd >= 0) { + err = show_btf(fd, &btf_prog_table, &btf_map_table); + close(fd); + goto exit_free; + } + + if (json_output) + jsonw_start_array(json_wtr); /* root array */ + + while (true) { + err = bpf_btf_get_next_id(id, &id); + if (err) { + if (errno == ENOENT) { + err = 0; + break; + } + p_err("can't get next BTF object: %s%s", + strerror(errno), + errno == EINVAL ? " -- kernel too old?" : ""); + err = -1; + break; + } + + fd = bpf_btf_get_fd_by_id(id); + if (fd < 0) { + if (errno == ENOENT) + continue; + p_err("can't get BTF object by id (%u): %s", + id, strerror(errno)); + err = -1; + break; + } + + err = show_btf(fd, &btf_prog_table, &btf_map_table); + close(fd); + if (err) + break; + } + + if (json_output) + jsonw_end_array(json_wtr); /* root array */ + +exit_free: + delete_btf_table(&btf_prog_table); + delete_btf_table(&btf_map_table); + + return err; +} + static int do_help(int argc, char **argv) { if (json_output) { @@ -530,7 +865,8 @@ static int do_help(int argc, char **argv) } fprintf(stderr, - "Usage: %s btf dump BTF_SRC [format FORMAT]\n" + "Usage: %s btf { show | list } [id BTF_ID]\n" + " %s btf dump BTF_SRC [format FORMAT]\n" " %s btf help\n" "\n" " BTF_SRC := { id BTF_ID | prog PROG | map MAP [{key | value | kv | all}] | file FILE }\n" @@ -539,12 +875,14 @@ static int do_help(int argc, char **argv) " " HELP_SPEC_PROGRAM "\n" " " HELP_SPEC_OPTIONS "\n" "", - bin_name, bin_name); + bin_name, bin_name, bin_name); return 0; } static const struct cmd cmds[] = { + { "show", do_show }, + { "list", do_show }, { "help", do_help }, { "dump", do_dump }, { 0 } |