From 622a5b582cc27d3deedc38fcef68da2972e8e58d Mon Sep 17 00:00:00 2001 From: Mauricio Vásquez Date: Fri, 7 Jan 2022 10:26:20 -0500 Subject: bpftool: Fix error check when calling hashmap__new() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit hashmap__new() encodes errors with ERR_PTR(), hence it's not valid to check the returned pointer against NULL and IS_ERR() has to be used instead. libbpf_get_error() can't be used in this case as hashmap__new() is not part of the public libbpf API and it'll continue using ERR_PTR() after libbpf 1.0. Fixes: 8f184732b60b ("bpftool: Switch to libbpf's hashmap for pinned paths of BPF objects") Fixes: 2828d0d75b73 ("bpftool: Switch to libbpf's hashmap for programs/maps in BTF listing") Fixes: d6699f8e0f83 ("bpftool: Switch to libbpf's hashmap for PIDs/names references") Signed-off-by: Mauricio Vásquez Signed-off-by: Andrii Nakryiko Reviewed-by: Quentin Monnet Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20220107152620.192327-2-mauricio@kinvolk.io --- tools/bpf/bpftool/btf.c | 2 +- tools/bpf/bpftool/link.c | 3 ++- tools/bpf/bpftool/map.c | 2 +- tools/bpf/bpftool/pids.c | 3 ++- tools/bpf/bpftool/prog.c | 2 +- 5 files changed, 7 insertions(+), 5 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c index 59833125ac0a..a2c665beda87 100644 --- a/tools/bpf/bpftool/btf.c +++ b/tools/bpf/bpftool/btf.c @@ -902,7 +902,7 @@ static int do_show(int argc, char **argv) equal_fn_for_key_as_id, NULL); btf_map_table = hashmap__new(hash_fn_for_key_as_id, equal_fn_for_key_as_id, NULL); - if (!btf_prog_table || !btf_map_table) { + if (IS_ERR(btf_prog_table) || IS_ERR(btf_map_table)) { hashmap__free(btf_prog_table); hashmap__free(btf_map_table); if (fd >= 0) diff --git a/tools/bpf/bpftool/link.c b/tools/bpf/bpftool/link.c index 2c258db0d352..97dec81950e5 100644 --- a/tools/bpf/bpftool/link.c +++ b/tools/bpf/bpftool/link.c @@ -2,6 +2,7 @@ /* Copyright (C) 2020 Facebook */ #include +#include #include #include #include @@ -306,7 +307,7 @@ static int do_show(int argc, char **argv) if (show_pinned) { link_table = hashmap__new(hash_fn_for_key_as_id, equal_fn_for_key_as_id, NULL); - if (!link_table) { + if (IS_ERR(link_table)) { p_err("failed to create hashmap for pinned paths"); return -1; } diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c index cc530a229812..c66a3c979b7a 100644 --- a/tools/bpf/bpftool/map.c +++ b/tools/bpf/bpftool/map.c @@ -699,7 +699,7 @@ static int do_show(int argc, char **argv) if (show_pinned) { map_table = hashmap__new(hash_fn_for_key_as_id, equal_fn_for_key_as_id, NULL); - if (!map_table) { + if (IS_ERR(map_table)) { p_err("failed to create hashmap for pinned paths"); return -1; } diff --git a/tools/bpf/bpftool/pids.c b/tools/bpf/bpftool/pids.c index 56b598eee043..7c384d10e95f 100644 --- a/tools/bpf/bpftool/pids.c +++ b/tools/bpf/bpftool/pids.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) /* Copyright (C) 2020 Facebook */ #include +#include #include #include #include @@ -101,7 +102,7 @@ int build_obj_refs_table(struct hashmap **map, enum bpf_obj_type type) libbpf_print_fn_t default_print; *map = hashmap__new(hash_fn_for_key_as_id, equal_fn_for_key_as_id, NULL); - if (!*map) { + if (IS_ERR(*map)) { p_err("failed to create hashmap for PID references"); return -1; } diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 2a21d50516bc..33ca834d5f51 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -641,7 +641,7 @@ static int do_show(int argc, char **argv) if (show_pinned) { prog_table = hashmap__new(hash_fn_for_key_as_id, equal_fn_for_key_as_id, NULL); - if (!prog_table) { + if (IS_ERR(prog_table)) { p_err("failed to create hashmap for pinned paths"); return -1; } -- cgit v1.2.3 From 0991f6a38f576aa9a5e34713e23c998a3310d4d0 Mon Sep 17 00:00:00 2001 From: Wei Fu Date: Sat, 8 Jan 2022 16:40:08 +0800 Subject: bpftool: Only set obj->skeleton on complete success After `bpftool gen skeleton`, the ${bpf_app}.skel.h will provide that ${bpf_app_name}__open helper to load bpf. If there is some error like ENOMEM, the ${bpf_app_name}__open will rollback(free) the allocated object, including `bpf_object_skeleton`. Since the ${bpf_app_name}__create_skeleton set the obj->skeleton first and not rollback it when error, it will cause double-free in ${bpf_app_name}__destory at ${bpf_app_name}__open. Therefore, we should set the obj->skeleton before return 0; Fixes: 5dc7a8b21144 ("bpftool, selftests/bpf: Embed object file inside skeleton") Signed-off-by: Wei Fu Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220108084008.1053111-1-fuweid89@gmail.com --- tools/bpf/bpftool/gen.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index b4695df2ea3d..a7387c265e3c 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -927,7 +927,6 @@ static int do_skeleton(int argc, char **argv) s = (struct bpf_object_skeleton *)calloc(1, sizeof(*s));\n\ if (!s) \n\ goto err; \n\ - obj->skeleton = s; \n\ \n\ s->sz = sizeof(*s); \n\ s->name = \"%1$s\"; \n\ @@ -1000,6 +999,7 @@ static int do_skeleton(int argc, char **argv) \n\ s->data = (void *)%2$s__elf_bytes(&s->data_sz); \n\ \n\ + obj->skeleton = s; \n\ return 0; \n\ err: \n\ bpf_object__destroy_skeleton(s); \n\ -- cgit v1.2.3 From 3c28919f0652a1952333b88e1af5ce408fafe238 Mon Sep 17 00:00:00 2001 From: Christy Lee Date: Fri, 7 Jan 2022 16:42:15 -0800 Subject: bpftool: Stop using bpf_map__def() API libbpf bpf_map__def() API is being deprecated, replace bpftool's usage with the appropriate getters and setters Signed-off-by: Christy Lee Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220108004218.355761-3-christylee@fb.com --- tools/bpf/bpftool/gen.c | 12 ++++++------ tools/bpf/bpftool/struct_ops.c | 4 +--- 2 files changed, 7 insertions(+), 9 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index a7387c265e3c..43e3f8700ecc 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -227,7 +227,7 @@ static int codegen_datasecs(struct bpf_object *obj, const char *obj_name) /* only generate definitions for memory-mapped internal maps */ if (!bpf_map__is_internal(map)) continue; - if (!(bpf_map__def(map)->map_flags & BPF_F_MMAPABLE)) + if (!(bpf_map__map_flags(map) & BPF_F_MMAPABLE)) continue; if (!get_map_ident(map, map_ident, sizeof(map_ident))) @@ -468,7 +468,7 @@ static void codegen_destroy(struct bpf_object *obj, const char *obj_name) if (!get_map_ident(map, ident, sizeof(ident))) continue; if (bpf_map__is_internal(map) && - (bpf_map__def(map)->map_flags & BPF_F_MMAPABLE)) + (bpf_map__map_flags(map) & BPF_F_MMAPABLE)) printf("\tmunmap(skel->%1$s, %2$zd);\n", ident, bpf_map_mmap_sz(map)); codegen("\ @@ -536,7 +536,7 @@ static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h continue; if (!bpf_map__is_internal(map) || - !(bpf_map__def(map)->map_flags & BPF_F_MMAPABLE)) + !(bpf_map__map_flags(map) & BPF_F_MMAPABLE)) continue; codegen("\ @@ -600,10 +600,10 @@ static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h continue; if (!bpf_map__is_internal(map) || - !(bpf_map__def(map)->map_flags & BPF_F_MMAPABLE)) + !(bpf_map__map_flags(map) & BPF_F_MMAPABLE)) continue; - if (bpf_map__def(map)->map_flags & BPF_F_RDONLY_PROG) + if (bpf_map__map_flags(map) & BPF_F_RDONLY_PROG) mmap_flags = "PROT_READ"; else mmap_flags = "PROT_READ | PROT_WRITE"; @@ -961,7 +961,7 @@ static int do_skeleton(int argc, char **argv) i, bpf_map__name(map), i, ident); /* memory-mapped internal maps */ if (bpf_map__is_internal(map) && - (bpf_map__def(map)->map_flags & BPF_F_MMAPABLE)) { + (bpf_map__map_flags(map) & BPF_F_MMAPABLE)) { printf("\ts->maps[%zu].mmaped = (void **)&obj->%s;\n", i, ident); } diff --git a/tools/bpf/bpftool/struct_ops.c b/tools/bpf/bpftool/struct_ops.c index 2f693b082bdb..e08a6ff2866c 100644 --- a/tools/bpf/bpftool/struct_ops.c +++ b/tools/bpf/bpftool/struct_ops.c @@ -480,7 +480,6 @@ static int do_unregister(int argc, char **argv) static int do_register(int argc, char **argv) { LIBBPF_OPTS(bpf_object_open_opts, open_opts); - const struct bpf_map_def *def; struct bpf_map_info info = {}; __u32 info_len = sizeof(info); int nr_errs = 0, nr_maps = 0; @@ -510,8 +509,7 @@ static int do_register(int argc, char **argv) } bpf_object__for_each_map(map, obj) { - def = bpf_map__def(map); - if (def->type != BPF_MAP_TYPE_STRUCT_OPS) + if (bpf_map__type(map) != BPF_MAP_TYPE_STRUCT_OPS) continue; link = bpf_map__attach_struct_ops(map); -- cgit v1.2.3 From b662000aff84f2ca9660db15e5f8ac926681df27 Mon Sep 17 00:00:00 2001 From: Raman Shukhau Date: Wed, 19 Jan 2022 02:02:55 -0800 Subject: bpftool: Adding support for BTF program names `bpftool prog list` and other bpftool subcommands that show BPF program names currently get them from bpf_prog_info.name. That field is limited to 16 (BPF_OBJ_NAME_LEN) chars which leads to truncated names since many progs have much longer names. The idea of this change is to improve all bpftool commands that output prog name so that bpftool uses info from BTF to print program names if available. It tries bpf_prog_info.name first and fall back to btf only if the name is suspected to be truncated (has 15 chars length). Right now `bpftool p show id ` returns capped prog name : kprobe name example_cap_cap tag 712e... ... With this change it would return : kprobe name example_cap_capable tag 712e... ... Note, other commands that print prog names (e.g. "bpftool cgroup tree") are also addressed in this change. Signed-off-by: Raman Shukhau Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220119100255.1068997-1-ramasha@fb.com --- tools/bpf/bpftool/cgroup.c | 6 ++++-- tools/bpf/bpftool/common.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ tools/bpf/bpftool/main.h | 4 ++++ tools/bpf/bpftool/prog.c | 28 ++++++++++++++++++---------- 4 files changed, 70 insertions(+), 12 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/cgroup.c b/tools/bpf/bpftool/cgroup.c index 3571a281c43f..effe136119d7 100644 --- a/tools/bpf/bpftool/cgroup.c +++ b/tools/bpf/bpftool/cgroup.c @@ -50,6 +50,7 @@ static int show_bpf_prog(int id, enum bpf_attach_type attach_type, const char *attach_flags_str, int level) { + char prog_name[MAX_PROG_FULL_NAME]; struct bpf_prog_info info = {}; __u32 info_len = sizeof(info); int prog_fd; @@ -63,6 +64,7 @@ static int show_bpf_prog(int id, enum bpf_attach_type attach_type, return -1; } + get_prog_full_name(&info, prog_fd, prog_name, sizeof(prog_name)); if (json_output) { jsonw_start_object(json_wtr); jsonw_uint_field(json_wtr, "id", info.id); @@ -73,7 +75,7 @@ static int show_bpf_prog(int id, enum bpf_attach_type attach_type, jsonw_uint_field(json_wtr, "attach_type", attach_type); jsonw_string_field(json_wtr, "attach_flags", attach_flags_str); - jsonw_string_field(json_wtr, "name", info.name); + jsonw_string_field(json_wtr, "name", prog_name); jsonw_end_object(json_wtr); } else { printf("%s%-8u ", level ? " " : "", info.id); @@ -81,7 +83,7 @@ static int show_bpf_prog(int id, enum bpf_attach_type attach_type, printf("%-15s", attach_type_name[attach_type]); else printf("type %-10u", attach_type); - printf(" %-15s %-15s\n", attach_flags_str, info.name); + printf(" %-15s %-15s\n", attach_flags_str, prog_name); } close(prog_fd); diff --git a/tools/bpf/bpftool/common.c b/tools/bpf/bpftool/common.c index fa8eb8134344..111dff809c7b 100644 --- a/tools/bpf/bpftool/common.c +++ b/tools/bpf/bpftool/common.c @@ -24,6 +24,7 @@ #include #include #include /* libbpf_num_possible_cpus */ +#include #include "main.h" @@ -304,6 +305,49 @@ const char *get_fd_type_name(enum bpf_obj_type type) return names[type]; } +void get_prog_full_name(const struct bpf_prog_info *prog_info, int prog_fd, + char *name_buff, size_t buff_len) +{ + const char *prog_name = prog_info->name; + const struct btf_type *func_type; + const struct bpf_func_info finfo; + struct bpf_prog_info info = {}; + __u32 info_len = sizeof(info); + struct btf *prog_btf = NULL; + + if (buff_len <= BPF_OBJ_NAME_LEN || + strlen(prog_info->name) < BPF_OBJ_NAME_LEN - 1) + goto copy_name; + + if (!prog_info->btf_id || prog_info->nr_func_info == 0) + goto copy_name; + + info.nr_func_info = 1; + info.func_info_rec_size = prog_info->func_info_rec_size; + if (info.func_info_rec_size > sizeof(finfo)) + info.func_info_rec_size = sizeof(finfo); + info.func_info = ptr_to_u64(&finfo); + + if (bpf_obj_get_info_by_fd(prog_fd, &info, &info_len)) + goto copy_name; + + prog_btf = btf__load_from_kernel_by_id(info.btf_id); + if (!prog_btf) + goto copy_name; + + func_type = btf__type_by_id(prog_btf, finfo.type_id); + if (!func_type || !btf_is_func(func_type)) + goto copy_name; + + prog_name = btf__name_by_offset(prog_btf, func_type->name_off); + +copy_name: + snprintf(name_buff, buff_len, "%s", prog_name); + + if (prog_btf) + btf__free(prog_btf); +} + int get_fd_type(int fd) { char path[PATH_MAX]; diff --git a/tools/bpf/bpftool/main.h b/tools/bpf/bpftool/main.h index 8d76d937a62b..0c3840596b5a 100644 --- a/tools/bpf/bpftool/main.h +++ b/tools/bpf/bpftool/main.h @@ -140,6 +140,10 @@ struct cmd { int cmd_select(const struct cmd *cmds, int argc, char **argv, int (*help)(int argc, char **argv)); +#define MAX_PROG_FULL_NAME 128 +void get_prog_full_name(const struct bpf_prog_info *prog_info, int prog_fd, + char *name_buff, size_t buff_len); + int get_fd_type(int fd); const char *get_fd_type_name(enum bpf_obj_type type); char *get_fdinfo(int fd, const char *key); diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 33ca834d5f51..cf935c63e6f5 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -424,8 +424,10 @@ out_free: free(value); } -static void print_prog_header_json(struct bpf_prog_info *info) +static void print_prog_header_json(struct bpf_prog_info *info, int fd) { + char prog_name[MAX_PROG_FULL_NAME]; + jsonw_uint_field(json_wtr, "id", info->id); if (info->type < ARRAY_SIZE(prog_type_name)) jsonw_string_field(json_wtr, "type", @@ -433,8 +435,10 @@ static void print_prog_header_json(struct bpf_prog_info *info) else jsonw_uint_field(json_wtr, "type", info->type); - if (*info->name) - jsonw_string_field(json_wtr, "name", info->name); + if (*info->name) { + get_prog_full_name(info, fd, prog_name, sizeof(prog_name)); + jsonw_string_field(json_wtr, "name", prog_name); + } jsonw_name(json_wtr, "tag"); jsonw_printf(json_wtr, "\"" BPF_TAG_FMT "\"", @@ -455,7 +459,7 @@ static void print_prog_json(struct bpf_prog_info *info, int fd) char *memlock; jsonw_start_object(json_wtr); - print_prog_header_json(info); + print_prog_header_json(info, fd); print_dev_json(info->ifindex, info->netns_dev, info->netns_ino); if (info->load_time) { @@ -507,16 +511,20 @@ static void print_prog_json(struct bpf_prog_info *info, int fd) jsonw_end_object(json_wtr); } -static void print_prog_header_plain(struct bpf_prog_info *info) +static void print_prog_header_plain(struct bpf_prog_info *info, int fd) { + char prog_name[MAX_PROG_FULL_NAME]; + printf("%u: ", info->id); if (info->type < ARRAY_SIZE(prog_type_name)) printf("%s ", prog_type_name[info->type]); else printf("type %u ", info->type); - if (*info->name) - printf("name %s ", info->name); + if (*info->name) { + get_prog_full_name(info, fd, prog_name, sizeof(prog_name)); + printf("name %s ", prog_name); + } printf("tag "); fprint_hex(stdout, info->tag, BPF_TAG_SIZE, ""); @@ -534,7 +542,7 @@ static void print_prog_plain(struct bpf_prog_info *info, int fd) { char *memlock; - print_prog_header_plain(info); + print_prog_header_plain(info, fd); if (info->load_time) { char buf[32]; @@ -972,10 +980,10 @@ static int do_dump(int argc, char **argv) if (json_output && nb_fds > 1) { jsonw_start_object(json_wtr); /* prog object */ - print_prog_header_json(&info); + print_prog_header_json(&info, fds[i]); jsonw_name(json_wtr, "insns"); } else if (nb_fds > 1) { - print_prog_header_plain(&info); + print_prog_header_plain(&info, fds[i]); } err = prog_dump(&info, mode, filepath, opcodes, visual, linum); -- cgit v1.2.3 From 93b8952d223af03c51fba0c6258173d2ffbd2cb7 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Wed, 19 Jan 2022 22:05:28 -0800 Subject: libbpf: deprecate legacy BPF map definitions Enact deprecation of legacy BPF map definition in SEC("maps") ([0]). For the definitions themselves introduce LIBBPF_STRICT_MAP_DEFINITIONS flag for libbpf strict mode. If it is set, error out on any struct bpf_map_def-based map definition. If not set, libbpf will print out a warning for each legacy BPF map to raise awareness that it goes away. For any use of BPF_ANNOTATE_KV_PAIR() macro providing a legacy way to associate BTF key/value type information with legacy BPF map definition, warn through libbpf's pr_warn() error message (but don't fail BPF object open). BPF-side struct bpf_map_def is marked as deprecated. User-space struct bpf_map_def has to be used internally in libbpf, so it is left untouched. It should be enough for bpf_map__def() to be marked deprecated to raise awareness that it goes away. bpftool is an interesting case that utilizes libbpf to open BPF ELF object to generate skeleton. As such, even though bpftool itself uses full on strict libbpf mode (LIBBPF_STRICT_ALL), it has to relax it a bit for BPF map definition handling to minimize unnecessary disruptions. So opt-out of LIBBPF_STRICT_MAP_DEFINITIONS for bpftool. User's code that will later use generated skeleton will make its own decision whether to enforce LIBBPF_STRICT_MAP_DEFINITIONS or not. There are few tests in selftests/bpf that are consciously using legacy BPF map definitions to test libbpf functionality. For those, temporary opt out of LIBBPF_STRICT_MAP_DEFINITIONS mode for the duration of those tests. [0] Closes: https://github.com/libbpf/libbpf/issues/272 Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/r/20220120060529.1890907-4-andrii@kernel.org Signed-off-by: Alexei Starovoitov --- tools/bpf/bpftool/main.c | 9 ++++++++- tools/lib/bpf/bpf_helpers.h | 2 +- tools/lib/bpf/libbpf.c | 8 ++++++++ tools/lib/bpf/libbpf_legacy.h | 5 +++++ tools/testing/selftests/bpf/prog_tests/btf.c | 4 ++++ 5 files changed, 26 insertions(+), 2 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c index 020e91a542d5..9d01fa9de033 100644 --- a/tools/bpf/bpftool/main.c +++ b/tools/bpf/bpftool/main.c @@ -478,7 +478,14 @@ int main(int argc, char **argv) } if (!legacy_libbpf) { - ret = libbpf_set_strict_mode(LIBBPF_STRICT_ALL); + enum libbpf_strict_mode mode; + + /* Allow legacy map definitions for skeleton generation. + * It will still be rejected if users use LIBBPF_STRICT_ALL + * mode for loading generated skeleton. + */ + mode = (__LIBBPF_STRICT_LAST - 1) & ~LIBBPF_STRICT_MAP_DEFINITIONS; + ret = libbpf_set_strict_mode(mode); if (ret) p_err("failed to enable libbpf strict mode: %d", ret); } diff --git a/tools/lib/bpf/bpf_helpers.h b/tools/lib/bpf/bpf_helpers.h index 963b1060d944..44df982d2a5c 100644 --- a/tools/lib/bpf/bpf_helpers.h +++ b/tools/lib/bpf/bpf_helpers.h @@ -133,7 +133,7 @@ struct bpf_map_def { unsigned int value_size; unsigned int max_entries; unsigned int map_flags; -}; +} __attribute__((deprecated("use BTF-defined maps in .maps section"))); enum libbpf_pin_type { LIBBPF_PIN_NONE, diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index fdb3536afa7d..fc6d530e20db 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -1937,6 +1937,11 @@ static int bpf_object__init_user_maps(struct bpf_object *obj, bool strict) if (obj->efile.maps_shndx < 0) return 0; + if (libbpf_mode & LIBBPF_STRICT_MAP_DEFINITIONS) { + pr_warn("legacy map definitions in SEC(\"maps\") are not supported\n"); + return -EOPNOTSUPP; + } + if (!symbols) return -EINVAL; @@ -1999,6 +2004,8 @@ static int bpf_object__init_user_maps(struct bpf_object *obj, bool strict) return -LIBBPF_ERRNO__FORMAT; } + pr_warn("map '%s' (legacy): legacy map definitions are deprecated, use BTF-defined maps instead\n", map_name); + if (ELF64_ST_BIND(sym->st_info) == STB_LOCAL) { pr_warn("map '%s' (legacy): static maps are not supported\n", map_name); return -ENOTSUP; @@ -4190,6 +4197,7 @@ static int bpf_map_find_btf_info(struct bpf_object *obj, struct bpf_map *map) return 0; if (!bpf_map__is_internal(map)) { + pr_warn("Use of BPF_ANNOTATE_KV_PAIR is deprecated, use BTF-defined maps in .maps section instead\n"); ret = btf__get_map_kv_tids(obj->btf, map->name, def->key_size, def->value_size, &key_type_id, &value_type_id); diff --git a/tools/lib/bpf/libbpf_legacy.h b/tools/lib/bpf/libbpf_legacy.h index 79131f761a27..3c2b281c2bc3 100644 --- a/tools/lib/bpf/libbpf_legacy.h +++ b/tools/lib/bpf/libbpf_legacy.h @@ -73,6 +73,11 @@ enum libbpf_strict_mode { * operation. */ LIBBPF_STRICT_AUTO_RLIMIT_MEMLOCK = 0x10, + /* + * Error out on any SEC("maps") map definition, which are deprecated + * in favor of BTF-defined map definitions in SEC(".maps"). + */ + LIBBPF_STRICT_MAP_DEFINITIONS = 0x20, __LIBBPF_STRICT_LAST, }; diff --git a/tools/testing/selftests/bpf/prog_tests/btf.c b/tools/testing/selftests/bpf/prog_tests/btf.c index 8ba53acf9eb4..14f9b6136794 100644 --- a/tools/testing/selftests/bpf/prog_tests/btf.c +++ b/tools/testing/selftests/bpf/prog_tests/btf.c @@ -4560,6 +4560,8 @@ static void do_test_file(unsigned int test_num) has_btf_ext = btf_ext != NULL; btf_ext__free(btf_ext); + /* temporary disable LIBBPF_STRICT_MAP_DEFINITIONS to test legacy maps */ + libbpf_set_strict_mode((__LIBBPF_STRICT_LAST - 1) & ~LIBBPF_STRICT_MAP_DEFINITIONS); obj = bpf_object__open(test->file); err = libbpf_get_error(obj); if (CHECK(err, "obj: %d", err)) @@ -4684,6 +4686,8 @@ skip: fprintf(stderr, "OK"); done: + libbpf_set_strict_mode(LIBBPF_STRICT_ALL); + btf__free(btf); free(func_info); bpf_object__close(obj); -- cgit v1.2.3 From c86575eccab24d583db0169ded342eb215b781c9 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Wed, 19 Jan 2022 22:14:20 -0800 Subject: bpftool: use new API for attaching XDP program Switch to new bpf_xdp_attach() API to avoid deprecation warnings. Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/r/20220120061422.2710637-3-andrii@kernel.org Signed-off-by: Alexei Starovoitov --- tools/bpf/bpftool/net.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/net.c b/tools/bpf/bpftool/net.c index 649053704bd7..526a332c48e6 100644 --- a/tools/bpf/bpftool/net.c +++ b/tools/bpf/bpftool/net.c @@ -551,7 +551,7 @@ static int do_attach_detach_xdp(int progfd, enum net_attach_type attach_type, if (attach_type == NET_ATTACH_TYPE_XDP_OFFLOAD) flags |= XDP_FLAGS_HW_MODE; - return bpf_set_link_xdp_fd(ifindex, progfd, flags); + return bpf_xdp_attach(ifindex, progfd, flags, NULL); } static int do_attach(int argc, char **argv) -- cgit v1.2.3 From 39748db1d6bc12b9f749a0aebe7ec71b00bd60eb Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Mon, 24 Jan 2022 11:42:51 -0800 Subject: bpftool: use preferred setters/getters instead of deprecated ones Use bpf_program__type() instead of discouraged bpf_program__get_type(). Also switch to bpf_map__set_max_entries() instead of bpf_map__resize(). Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/r/20220124194254.2051434-5-andrii@kernel.org Signed-off-by: Alexei Starovoitov --- tools/bpf/bpftool/gen.c | 2 +- tools/bpf/bpftool/prog.c | 8 ++++---- 2 files changed, 5 insertions(+), 5 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index 43e3f8700ecc..8f78c27d41f0 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -378,7 +378,7 @@ static void codegen_attach_detach(struct bpf_object *obj, const char *obj_name) int prog_fd = skel->progs.%2$s.prog_fd; \n\ ", obj_name, bpf_program__name(prog)); - switch (bpf_program__get_type(prog)) { + switch (bpf_program__type(prog)) { case BPF_PROG_TYPE_RAW_TRACEPOINT: tp_name = strchr(bpf_program__section_name(prog), '/') + 1; printf("\tint fd = bpf_raw_tracepoint_open(\"%s\", prog_fd);\n", tp_name); diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index cf935c63e6f5..87593f98d2d1 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -2283,10 +2283,10 @@ static int do_profile(int argc, char **argv) profile_obj->rodata->num_metric = num_metric; /* adjust map sizes */ - bpf_map__resize(profile_obj->maps.events, num_metric * num_cpu); - bpf_map__resize(profile_obj->maps.fentry_readings, num_metric); - bpf_map__resize(profile_obj->maps.accum_readings, num_metric); - bpf_map__resize(profile_obj->maps.counts, 1); + bpf_map__set_max_entries(profile_obj->maps.events, num_metric * num_cpu); + bpf_map__set_max_entries(profile_obj->maps.fentry_readings, num_metric); + bpf_map__set_max_entries(profile_obj->maps.accum_readings, num_metric); + bpf_map__set_max_entries(profile_obj->maps.counts, 1); /* change target name */ profile_tgt_name = profile_target_name(profile_tgt_fd); -- cgit v1.2.3 From 42d1d53fedc9980e8fed98a5a03762cba7d2e9f6 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Mon, 31 Jan 2022 14:05:22 -0800 Subject: libbpf: Add support for bpf iter in light skeleton. bpf iterator programs should use bpf_link_create to attach instead of bpf_raw_tracepoint_open like other tracing programs. Signed-off-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann Acked-by: Martin KaFai Lau Link: https://lore.kernel.org/bpf/20220131220528.98088-2-alexei.starovoitov@gmail.com --- tools/bpf/bpftool/gen.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index 8f78c27d41f0..8eacfc79ec43 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -384,7 +384,10 @@ static void codegen_attach_detach(struct bpf_object *obj, const char *obj_name) printf("\tint fd = bpf_raw_tracepoint_open(\"%s\", prog_fd);\n", tp_name); break; case BPF_PROG_TYPE_TRACING: - printf("\tint fd = bpf_raw_tracepoint_open(NULL, prog_fd);\n"); + if (bpf_program__expected_attach_type(prog) == BPF_TRACE_ITER) + printf("\tint fd = bpf_link_create(prog_fd, 0, BPF_TRACE_ITER, NULL);\n"); + else + printf("\tint fd = bpf_raw_tracepoint_open(NULL, prog_fd);\n"); break; default: printf("\tint fd = ((void)prog_fd, 0); /* auto-attach not supported */\n"); -- cgit v1.2.3 From c69f94a33d12a9c49f1800c54838ee19447ac176 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Mon, 31 Jan 2022 14:05:24 -0800 Subject: libbpf: Open code raw_tp_open and link_create commands. Open code raw_tracepoint_open and link_create used by light skeleton to be able to avoid full libbpf eventually. Signed-off-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann Acked-by: Martin KaFai Lau Link: https://lore.kernel.org/bpf/20220131220528.98088-4-alexei.starovoitov@gmail.com --- tools/bpf/bpftool/gen.c | 6 +++--- tools/lib/bpf/skel_internal.h | 26 ++++++++++++++++++++++++++ 2 files changed, 29 insertions(+), 3 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index 8eacfc79ec43..eacfc6a2060d 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -381,13 +381,13 @@ static void codegen_attach_detach(struct bpf_object *obj, const char *obj_name) switch (bpf_program__type(prog)) { case BPF_PROG_TYPE_RAW_TRACEPOINT: tp_name = strchr(bpf_program__section_name(prog), '/') + 1; - printf("\tint fd = bpf_raw_tracepoint_open(\"%s\", prog_fd);\n", tp_name); + printf("\tint fd = skel_raw_tracepoint_open(\"%s\", prog_fd);\n", tp_name); break; case BPF_PROG_TYPE_TRACING: if (bpf_program__expected_attach_type(prog) == BPF_TRACE_ITER) - printf("\tint fd = bpf_link_create(prog_fd, 0, BPF_TRACE_ITER, NULL);\n"); + printf("\tint fd = skel_link_create(prog_fd, 0, BPF_TRACE_ITER);\n"); else - printf("\tint fd = bpf_raw_tracepoint_open(NULL, prog_fd);\n"); + printf("\tint fd = skel_raw_tracepoint_open(NULL, prog_fd);\n"); break; default: printf("\tint fd = ((void)prog_fd, 0); /* auto-attach not supported */\n"); diff --git a/tools/lib/bpf/skel_internal.h b/tools/lib/bpf/skel_internal.h index 57507f1c1934..dcd3336512d4 100644 --- a/tools/lib/bpf/skel_internal.h +++ b/tools/lib/bpf/skel_internal.h @@ -110,6 +110,32 @@ static inline int skel_map_update_elem(int fd, const void *key, return skel_sys_bpf(BPF_MAP_UPDATE_ELEM, &attr, attr_sz); } +static inline int skel_raw_tracepoint_open(const char *name, int prog_fd) +{ + const size_t attr_sz = offsetofend(union bpf_attr, raw_tracepoint.prog_fd); + union bpf_attr attr; + + memset(&attr, 0, attr_sz); + attr.raw_tracepoint.name = (long) name; + attr.raw_tracepoint.prog_fd = prog_fd; + + return skel_sys_bpf(BPF_RAW_TRACEPOINT_OPEN, &attr, attr_sz); +} + +static inline int skel_link_create(int prog_fd, int target_fd, + enum bpf_attach_type attach_type) +{ + const size_t attr_sz = offsetofend(union bpf_attr, link_create.iter_info_len); + union bpf_attr attr; + + memset(&attr, 0, attr_sz); + attr.link_create.prog_fd = prog_fd; + attr.link_create.target_fd = target_fd; + attr.link_create.attach_type = attach_type; + + return skel_sys_bpf(BPF_LINK_CREATE, &attr, attr_sz); +} + static inline int bpf_load_and_run(struct bpf_load_and_run_opts *opts) { int map_fd = -1, prog_fd = -1, key = 0, err; -- cgit v1.2.3 From 9cce53138dd9ee8bd7354196297df24130f3529d Mon Sep 17 00:00:00 2001 From: Delyan Kratunov Date: Wed, 2 Feb 2022 15:54:22 -0800 Subject: bpftool: Migrate from bpf_prog_test_run_xattr bpf_prog_test_run is being deprecated in favor of the OPTS-based bpf_prog_test_run_opts. Signed-off-by: Delyan Kratunov Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220202235423.1097270-4-delyank@fb.com --- tools/bpf/bpftool/prog.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 87593f98d2d1..92a6f679ef7d 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -1272,12 +1272,12 @@ static int do_run(int argc, char **argv) { char *data_fname_in = NULL, *data_fname_out = NULL; char *ctx_fname_in = NULL, *ctx_fname_out = NULL; - struct bpf_prog_test_run_attr test_attr = {0}; const unsigned int default_size = SZ_32K; void *data_in = NULL, *data_out = NULL; void *ctx_in = NULL, *ctx_out = NULL; unsigned int repeat = 1; int fd, err; + LIBBPF_OPTS(bpf_test_run_opts, test_attr); if (!REQ_ARGS(4)) return -1; @@ -1395,14 +1395,13 @@ static int do_run(int argc, char **argv) goto free_ctx_in; } - test_attr.prog_fd = fd; test_attr.repeat = repeat; test_attr.data_in = data_in; test_attr.data_out = data_out; test_attr.ctx_in = ctx_in; test_attr.ctx_out = ctx_out; - err = bpf_prog_test_run_xattr(&test_attr); + err = bpf_prog_test_run_opts(fd, &test_attr); if (err) { p_err("failed to run program: %s", strerror(errno)); goto free_ctx_out; -- cgit v1.2.3 From 1a56c18e6c2e4e7482ac9e1a4ffe1770841dd6bd Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Wed, 2 Feb 2022 14:59:12 -0800 Subject: bpftool: Stop supporting BPF offload-enabled feature probing libbpf 1.0 is not going to support passing ifindex to BPF prog/map/helper feature probing APIs. Remove the support for BPF offload feature probing. Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Reviewed-by: Quentin Monnet Link: https://lore.kernel.org/bpf/20220202225916.3313522-3-andrii@kernel.org --- tools/bpf/bpftool/feature.c | 29 +++++++++++++++++------------ 1 file changed, 17 insertions(+), 12 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/feature.c b/tools/bpf/bpftool/feature.c index e999159fa28d..9c894b1447de 100644 --- a/tools/bpf/bpftool/feature.c +++ b/tools/bpf/bpftool/feature.c @@ -487,17 +487,12 @@ probe_prog_type(enum bpf_prog_type prog_type, bool *supported_types, size_t maxlen; bool res; - if (ifindex) - /* Only test offload-able program types */ - switch (prog_type) { - case BPF_PROG_TYPE_SCHED_CLS: - case BPF_PROG_TYPE_XDP: - break; - default: - return; - } + if (ifindex) { + p_info("BPF offload feature probing is not supported"); + return; + } - res = bpf_probe_prog_type(prog_type, ifindex); + res = libbpf_probe_bpf_prog_type(prog_type, NULL); #ifdef USE_LIBCAP /* Probe may succeed even if program load fails, for unprivileged users * check that we did not fail because of insufficient permissions @@ -535,7 +530,12 @@ probe_map_type(enum bpf_map_type map_type, const char *define_prefix, size_t maxlen; bool res; - res = bpf_probe_map_type(map_type, ifindex); + if (ifindex) { + p_info("BPF offload feature probing is not supported"); + return; + } + + res = libbpf_probe_bpf_map_type(map_type, NULL); /* Probe result depends on the success of map creation, no additional * check required for unprivileged users @@ -567,7 +567,12 @@ probe_helper_for_progtype(enum bpf_prog_type prog_type, bool supported_type, bool res = false; if (supported_type) { - res = bpf_probe_helper(id, prog_type, ifindex); + if (ifindex) { + p_info("BPF offload feature probing is not supported"); + return; + } + + res = libbpf_probe_bpf_helper(prog_type, id, NULL); #ifdef USE_LIBCAP /* Probe may succeed even if program load fails, for * unprivileged users check that we did not fail because of -- cgit v1.2.3 From a9a8ac592e47ff35363308ad4c66740724132aa3 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Wed, 2 Feb 2022 14:59:13 -0800 Subject: bpftool: Fix uninit variable compilation warning Newer GCC complains about capturing the address of unitialized variable. While there is nothing wrong with the code (the variable is filled out by the kernel), initialize the variable anyway to make compiler happy. Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Reviewed-by: Quentin Monnet Link: https://lore.kernel.org/bpf/20220202225916.3313522-4-andrii@kernel.org --- tools/bpf/bpftool/common.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/common.c b/tools/bpf/bpftool/common.c index 111dff809c7b..606743c6db41 100644 --- a/tools/bpf/bpftool/common.c +++ b/tools/bpf/bpftool/common.c @@ -310,7 +310,7 @@ void get_prog_full_name(const struct bpf_prog_info *prog_info, int prog_fd, { const char *prog_name = prog_info->name; const struct btf_type *func_type; - const struct bpf_func_info finfo; + const struct bpf_func_info finfo = {}; struct bpf_prog_info info = {}; __u32 info_len = sizeof(info); struct btf *prog_btf = NULL; -- cgit v1.2.3 From da7af0aa20f8ad89f09d50d262e44cd5eafab816 Mon Sep 17 00:00:00 2001 From: Mauricio Vásquez Date: Mon, 7 Feb 2022 09:50:51 -0500 Subject: bpftool: Fix strict mode calculation MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit "(__LIBBPF_STRICT_LAST - 1) & ~LIBBPF_STRICT_MAP_DEFINITIONS" is wrong as it is equal to 0 (LIBBPF_STRICT_NONE). Let's use "LIBBPF_STRICT_ALL & ~LIBBPF_STRICT_MAP_DEFINITIONS" now that the previous commit makes it possible in libbpf. Fixes: 93b8952d223a ("libbpf: deprecate legacy BPF map definitions") Signed-off-by: Mauricio Vásquez Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220207145052.124421-3-mauricio@kinvolk.io --- tools/bpf/bpftool/main.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c index 9d01fa9de033..490f7bd54e4c 100644 --- a/tools/bpf/bpftool/main.c +++ b/tools/bpf/bpftool/main.c @@ -478,14 +478,11 @@ int main(int argc, char **argv) } if (!legacy_libbpf) { - enum libbpf_strict_mode mode; - /* Allow legacy map definitions for skeleton generation. * It will still be rejected if users use LIBBPF_STRICT_ALL * mode for loading generated skeleton. */ - mode = (__LIBBPF_STRICT_LAST - 1) & ~LIBBPF_STRICT_MAP_DEFINITIONS; - ret = libbpf_set_strict_mode(mode); + ret = libbpf_set_strict_mode(LIBBPF_STRICT_ALL & ~LIBBPF_STRICT_MAP_DEFINITIONS); if (ret) p_err("failed to enable libbpf strict mode: %d", ret); } -- cgit v1.2.3 From 28d743f671272d7a5f676669c84438b0f9600936 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Wed, 9 Feb 2022 15:19:59 -0800 Subject: bpftool: Generalize light skeleton generation. Generealize light skeleton by hiding mmap details in skel_internal.h In this form generated lskel.h is usable both by user space and by the kernel. Note that previously #include was in *.lskel.h file. To avoid #ifdef-s in a generated lskel.h the include of bpf.h is moved to skel_internal.h, but skel_internal.h is also used by gen_loader.c which is part of libbpf. Therefore skel_internal.h does #include "bpf.h" in case of user space, so gen_loader.c and lskel.h have necessary definitions. Signed-off-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann Acked-by: Yonghong Song Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220209232001.27490-4-alexei.starovoitov@gmail.com --- tools/bpf/bpftool/gen.c | 39 ++++++++++++++++++++------------------- 1 file changed, 20 insertions(+), 19 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index eacfc6a2060d..6f2e20be0c62 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -472,7 +472,7 @@ static void codegen_destroy(struct bpf_object *obj, const char *obj_name) continue; if (bpf_map__is_internal(map) && (bpf_map__map_flags(map) & BPF_F_MMAPABLE)) - printf("\tmunmap(skel->%1$s, %2$zd);\n", + printf("\tskel_free_map_data(skel->%1$s, skel->maps.%1$s.initial_value, %2$zd);\n", ident, bpf_map_mmap_sz(map)); codegen("\ \n\ @@ -481,7 +481,7 @@ static void codegen_destroy(struct bpf_object *obj, const char *obj_name) } codegen("\ \n\ - free(skel); \n\ + skel_free(skel); \n\ } \n\ ", obj_name); @@ -525,7 +525,7 @@ static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h { \n\ struct %1$s *skel; \n\ \n\ - skel = calloc(sizeof(*skel), 1); \n\ + skel = skel_alloc(sizeof(*skel)); \n\ if (!skel) \n\ goto cleanup; \n\ skel->ctx.sz = (void *)&skel->links - (void *)skel; \n\ @@ -543,19 +543,18 @@ static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h continue; codegen("\ - \n\ - skel->%1$s = \n\ - mmap(NULL, %2$zd, PROT_READ | PROT_WRITE,\n\ - MAP_SHARED | MAP_ANONYMOUS, -1, 0); \n\ - if (skel->%1$s == (void *) -1) \n\ - goto cleanup; \n\ - memcpy(skel->%1$s, (void *)\"\\ \n\ - ", ident, bpf_map_mmap_sz(map)); + \n\ + skel->%1$s = skel_prep_map_data((void *)\"\\ \n\ + ", ident); mmap_data = bpf_map__initial_value(map, &mmap_size); print_hex(mmap_data, mmap_size); - printf("\", %2$zd);\n" - "\tskel->maps.%1$s.initial_value = (__u64)(long)skel->%1$s;\n", - ident, mmap_size); + codegen("\ + \n\ + \", %1$zd, %2$zd); \n\ + if (!skel->%3$s) \n\ + goto cleanup; \n\ + skel->maps.%3$s.initial_value = (__u64) (long) skel->%3$s;\n\ + ", bpf_map_mmap_sz(map), mmap_size, ident); } codegen("\ \n\ @@ -611,9 +610,13 @@ static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h else mmap_flags = "PROT_READ | PROT_WRITE"; - printf("\tskel->%1$s =\n" - "\t\tmmap(skel->%1$s, %2$zd, %3$s, MAP_SHARED | MAP_FIXED,\n" - "\t\t\tskel->maps.%1$s.map_fd, 0);\n", + codegen("\ + \n\ + skel->%1$s = skel_finalize_map_data(&skel->maps.%1$s.initial_value, \n\ + %2$zd, %3$s, skel->maps.%1$s.map_fd);\n\ + if (!skel->%1$s) \n\ + return -ENOMEM; \n\ + ", ident, bpf_map_mmap_sz(map), mmap_flags); } codegen("\ @@ -751,8 +754,6 @@ static int do_skeleton(int argc, char **argv) #ifndef %2$s \n\ #define %2$s \n\ \n\ - #include \n\ - #include \n\ #include \n\ \n\ struct %1$s { \n\ -- cgit v1.2.3 From 61fce9693f0311949c59cc62a8fdee6e36243553 Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Thu, 10 Feb 2022 10:42:36 +0000 Subject: bpftool: Add libbpf's version number to "bpftool version" output To help users check what version of libbpf is being used with bpftool, print the number along with bpftool's own version number. Output: $ ./bpftool version ./bpftool v5.16.0 using libbpf v0.7 features: libbfd, libbpf_strict, skeletons $ ./bpftool version --json --pretty { "version": "5.16.0", "libbpf_version": "0.7", "features": { "libbfd": true, "libbpf_strict": true, "skeletons": true } } Note that libbpf does not expose its patch number. Signed-off-by: Quentin Monnet Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220210104237.11649-2-quentin@isovalent.com --- tools/bpf/bpftool/Documentation/common_options.rst | 13 +++++++------ tools/bpf/bpftool/main.c | 4 ++++ 2 files changed, 11 insertions(+), 6 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/Documentation/common_options.rst b/tools/bpf/bpftool/Documentation/common_options.rst index 908487b9c2ad..4107a586b68b 100644 --- a/tools/bpf/bpftool/Documentation/common_options.rst +++ b/tools/bpf/bpftool/Documentation/common_options.rst @@ -4,12 +4,13 @@ Print short help message (similar to **bpftool help**). -V, --version - Print version number (similar to **bpftool version**), and optional - features that were included when bpftool was compiled. Optional - features include linking against libbfd to provide the disassembler - for JIT-ted programs (**bpftool prog dump jited**) and usage of BPF - skeletons (some features like **bpftool prog profile** or showing - pids associated to BPF objects may rely on it). + Print bpftool's version number (similar to **bpftool version**), the + number of the libbpf version in use, and optional features that were + included when bpftool was compiled. Optional features include linking + against libbfd to provide the disassembler for JIT-ted programs + (**bpftool prog dump jited**) and usage of BPF skeletons (some + features like **bpftool prog profile** or showing pids associated to + BPF objects may rely on it). -j, --json Generate JSON output. For commands that cannot produce JSON, this diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c index 490f7bd54e4c..0f2f8de514a4 100644 --- a/tools/bpf/bpftool/main.c +++ b/tools/bpf/bpftool/main.c @@ -89,6 +89,9 @@ static int do_version(int argc, char **argv) jsonw_name(json_wtr, "version"); jsonw_printf(json_wtr, "\"%s\"", BPFTOOL_VERSION); + jsonw_name(json_wtr, "libbpf_version"); + jsonw_printf(json_wtr, "\"%d.%d\"", + libbpf_major_version(), libbpf_minor_version()); jsonw_name(json_wtr, "features"); jsonw_start_object(json_wtr); /* features */ @@ -102,6 +105,7 @@ static int do_version(int argc, char **argv) unsigned int nb_features = 0; printf("%s v%s\n", bin_name, BPFTOOL_VERSION); + printf("using libbpf %s\n", libbpf_version_string()); printf("features:"); if (has_libbfd) { printf(" libbfd"); -- cgit v1.2.3 From 9910a74d6ebf6e35d7adfae665022674fb90ea78 Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Thu, 10 Feb 2022 10:42:37 +0000 Subject: bpftool: Update versioning scheme, align on libbpf's version number Since the notion of versions was introduced for bpftool, it has been following the version number of the kernel (using the version number corresponding to the tree in which bpftool's sources are located). The rationale was that bpftool's features are loosely tied to BPF features in the kernel, and that we could defer versioning to the kernel repository itself. But this versioning scheme is confusing today, because a bpftool binary should be able to work with both older and newer kernels, even if some of its recent features won't be available on older systems. Furthermore, if bpftool is ported to other systems in the future, keeping a Linux-based version number is not a good option. Looking at other options, we could either have a totally independent scheme for bpftool, or we could align it on libbpf's version number (with an offset on the major version number, to avoid going backwards). The latter comes with a few drawbacks: - We may want bpftool releases in-between two libbpf versions. We can always append pre-release numbers to distinguish versions, although those won't look as "official" as something with a proper release number. But at the same time, having bpftool with version numbers that look "official" hasn't really been an issue so far. - If no new feature lands in bpftool for some time, we may move from e.g. 6.7.0 to 6.8.0 when libbpf levels up and have two different versions which are in fact the same. - Following libbpf's versioning scheme sounds better than kernel's, but ultimately it doesn't make too much sense either, because even though bpftool uses the lib a lot, its behaviour is not that much conditioned by the internal evolution of the library (or by new APIs that it may not use). Having an independent versioning scheme solves the above, but at the cost of heavier maintenance. Developers will likely forget to increase the numbers when adding features or bug fixes, and we would take the risk of having to send occasional "catch-up" patches just to update the version number. Based on these considerations, this patch aligns bpftool's version number on libbpf's. This is not a perfect solution, but 1) it's certainly an improvement over the current scheme, 2) the issues raised above are all minor at the moment, and 3) we can still move to an independent scheme in the future if we realise we need it. Given that libbpf is currently at version 0.7.0, and bpftool, before this patch, was at 5.16, we use an offset of 6 for the major version, bumping bpftool to 6.7.0. Libbpf does not export its patch number; leave bpftool's patch number at 0 for now. It remains possible to manually override the version number by setting BPFTOOL_VERSION when calling make. Signed-off-by: Quentin Monnet Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220210104237.11649-3-quentin@isovalent.com --- tools/bpf/bpftool/Makefile | 6 ++---- tools/bpf/bpftool/main.c | 21 +++++++++++++++++++++ 2 files changed, 23 insertions(+), 4 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile index 83369f55df61..94b2c2f4ad43 100644 --- a/tools/bpf/bpftool/Makefile +++ b/tools/bpf/bpftool/Makefile @@ -39,10 +39,6 @@ LIBBPF_BOOTSTRAP := $(LIBBPF_BOOTSTRAP_OUTPUT)libbpf.a LIBBPF_INTERNAL_HDRS := $(addprefix $(LIBBPF_HDRS_DIR)/,hashmap.h nlattr.h) LIBBPF_BOOTSTRAP_INTERNAL_HDRS := $(addprefix $(LIBBPF_BOOTSTRAP_HDRS_DIR)/,hashmap.h) -ifeq ($(BPFTOOL_VERSION),) -BPFTOOL_VERSION := $(shell make -rR --no-print-directory -sC ../../.. kernelversion) -endif - $(LIBBPF_OUTPUT) $(BOOTSTRAP_OUTPUT) $(LIBBPF_BOOTSTRAP_OUTPUT) $(LIBBPF_HDRS_DIR) $(LIBBPF_BOOTSTRAP_HDRS_DIR): $(QUIET_MKDIR)mkdir -p $@ @@ -83,7 +79,9 @@ CFLAGS += -DPACKAGE='"bpftool"' -D__EXPORTED_HEADERS__ \ -I$(srctree)/kernel/bpf/ \ -I$(srctree)/tools/include \ -I$(srctree)/tools/include/uapi +ifneq ($(BPFTOOL_VERSION),) CFLAGS += -DBPFTOOL_VERSION='"$(BPFTOOL_VERSION)"' +endif ifneq ($(EXTRA_CFLAGS),) CFLAGS += $(EXTRA_CFLAGS) endif diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c index 0f2f8de514a4..e81227761f5d 100644 --- a/tools/bpf/bpftool/main.c +++ b/tools/bpf/bpftool/main.c @@ -71,6 +71,17 @@ static int do_help(int argc, char **argv) return 0; } +#ifndef BPFTOOL_VERSION +/* bpftool's major and minor version numbers are aligned on libbpf's. There is + * an offset of 6 for the version number, because bpftool's version was higher + * than libbpf's when we adopted this scheme. The patch number remains at 0 + * for now. Set BPFTOOL_VERSION to override. + */ +#define BPFTOOL_MAJOR_VERSION (LIBBPF_MAJOR_VERSION + 6) +#define BPFTOOL_MINOR_VERSION LIBBPF_MINOR_VERSION +#define BPFTOOL_PATCH_VERSION 0 +#endif + static int do_version(int argc, char **argv) { #ifdef HAVE_LIBBFD_SUPPORT @@ -88,7 +99,12 @@ static int do_version(int argc, char **argv) jsonw_start_object(json_wtr); /* root object */ jsonw_name(json_wtr, "version"); +#ifdef BPFTOOL_VERSION jsonw_printf(json_wtr, "\"%s\"", BPFTOOL_VERSION); +#else + jsonw_printf(json_wtr, "\"%d.%d.%d\"", BPFTOOL_MAJOR_VERSION, + BPFTOOL_MINOR_VERSION, BPFTOOL_PATCH_VERSION); +#endif jsonw_name(json_wtr, "libbpf_version"); jsonw_printf(json_wtr, "\"%d.%d\"", libbpf_major_version(), libbpf_minor_version()); @@ -104,7 +120,12 @@ static int do_version(int argc, char **argv) } else { unsigned int nb_features = 0; +#ifdef BPFTOOL_VERSION printf("%s v%s\n", bin_name, BPFTOOL_VERSION); +#else + printf("%s v%d.%d.%d\n", bin_name, BPFTOOL_MAJOR_VERSION, + BPFTOOL_MINOR_VERSION, BPFTOOL_PATCH_VERSION); +#endif printf("using libbpf %s\n", libbpf_version_string()); printf("features:"); if (has_libbfd) { -- cgit v1.2.3 From edc21dc909c6c133a2727f063eadd7907af51f94 Mon Sep 17 00:00:00 2001 From: Yinjun Zhang Date: Tue, 8 Feb 2022 00:00:25 +0800 Subject: bpftool: Fix the error when lookup in no-btf maps MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When reworking btf__get_from_id() in commit a19f93cfafdf the error handling when calling bpf_btf_get_fd_by_id() changed. Before the rework if bpf_btf_get_fd_by_id() failed the error would not be propagated to callers of btf__get_from_id(), after the rework it is. This lead to a change in behavior in print_key_value() that now prints an error when trying to lookup keys in maps with no btf available. Fix this by following the way used in dumping maps to allow to look up keys in no-btf maps, by which it decides whether and where to get the btf info according to the btf value type. Fixes: a19f93cfafdf ("libbpf: Add internal helper to load BTF data by FD") Signed-off-by: Yinjun Zhang Signed-off-by: Simon Horman Signed-off-by: Andrii Nakryiko Reviewed-by: Niklas Söderlund Acked-by: Jiri Olsa Link: https://lore.kernel.org/bpf/1644249625-22479-1-git-send-email-yinjun.zhang@corigine.com --- tools/bpf/bpftool/map.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c index c66a3c979b7a..7a341a472ea4 100644 --- a/tools/bpf/bpftool/map.c +++ b/tools/bpf/bpftool/map.c @@ -1054,11 +1054,9 @@ static void print_key_value(struct bpf_map_info *info, void *key, json_writer_t *btf_wtr; struct btf *btf; - btf = btf__load_from_kernel_by_id(info->btf_id); - if (libbpf_get_error(btf)) { - p_err("failed to get btf"); + btf = get_map_kv_btf(info); + if (libbpf_get_error(btf)) return; - } if (json_output) { print_entry_json(info, key, value, btf); -- cgit v1.2.3 From bb8ffe61ea454a565e4fb1f450ef71237c9f032c Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Fri, 11 Feb 2022 21:57:32 -0800 Subject: bpftool: Add C++-specific open/load/etc skeleton wrappers Add C++-specific static methods for code-generated BPF skeleton for each skeleton operation: open, open_opts, open_and_load, load, attach, detach, destroy, and elf_bytes. This is to facilitate easier C++ templating on top of pure C BPF skeleton. In C, open/load/destroy/etc "methods" are of the form __() to avoid name collision with similar "methods" of other skeletons withint the same application. This works well, but is very inconvenient for C++ applications that would like to write generic (templated) wrappers around BPF skeleton to fit in with C++ code base and take advantage of destructors and other convenient C++ constructs. This patch makes it easier to build such generic templated wrappers by additionally defining C++ static methods for skeleton's struct with fixed names. This allows to refer to, say, open method as `T::open()` instead of having to somehow generate `T__open()` function call. Next patch adds an example template to test_cpp selftest to demonstrate how it's possible to have all the operations wrapped in a generic Skeleton type without explicitly passing function references. An example of generated declaration section without %1$s placeholders: #ifdef __cplusplus static struct test_attach_probe *open(const struct bpf_object_open_opts *opts = nullptr); static struct test_attach_probe *open_and_load(); static int load(struct test_attach_probe *skel); static int attach(struct test_attach_probe *skel); static void detach(struct test_attach_probe *skel); static void destroy(struct test_attach_probe *skel); static const void *elf_bytes(size_t *sz); #endif /* __cplusplus */ Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20220212055733.539056-2-andrii@kernel.org --- tools/bpf/bpftool/gen.c | 24 ++++++++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index 6f2e20be0c62..022f30490567 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -831,6 +831,16 @@ static int do_skeleton(int argc, char **argv) codegen("\ \n\ + \n\ + #ifdef __cplusplus \n\ + static struct %1$s *open(const struct bpf_object_open_opts *opts = nullptr);\n\ + static struct %1$s *open_and_load(); \n\ + static int load(struct %1$s *skel); \n\ + static int attach(struct %1$s *skel); \n\ + static void detach(struct %1$s *skel); \n\ + static void destroy(struct %1$s *skel); \n\ + static const void *elf_bytes(size_t *sz); \n\ + #endif /* __cplusplus */ \n\ }; \n\ \n\ static void \n\ @@ -1025,9 +1035,19 @@ static int do_skeleton(int argc, char **argv) \"; \n\ } \n\ \n\ - #endif /* %s */ \n\ + #ifdef __cplusplus \n\ + struct %1$s *%1$s::open(const struct bpf_object_open_opts *opts) { return %1$s__open_opts(opts); }\n\ + struct %1$s *%1$s::open_and_load() { return %1$s__open_and_load(); } \n\ + int %1$s::load(struct %1$s *skel) { return %1$s__load(skel); } \n\ + int %1$s::attach(struct %1$s *skel) { return %1$s__attach(skel); } \n\ + void %1$s::detach(struct %1$s *skel) { %1$s__detach(skel); } \n\ + void %1$s::destroy(struct %1$s *skel) { %1$s__destroy(skel); } \n\ + const void *%1$s::elf_bytes(size_t *sz) { return %1$s__elf_bytes(sz); } \n\ + #endif /* __cplusplus */ \n\ + \n\ + #endif /* %2$s */ \n\ ", - header_guard); + obj_name, header_guard); err = 0; out: bpf_object__close(obj); -- cgit v1.2.3 From 0a9f4a20c6153d187c8ee58133357ac671372f5f Mon Sep 17 00:00:00 2001 From: Mauricio Vásquez Date: Tue, 15 Feb 2022 17:58:52 -0500 Subject: bpftool: Add gen min_core_btf command MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This command is implemented under the "gen" command in bpftool and the syntax is the following: $ bpftool gen min_core_btf INPUT OUTPUT OBJECT [OBJECT...] INPUT is the file that contains all the BTF types for a kernel and OUTPUT is the path of the minimize BTF file that will be created with only the types needed by the objects. Signed-off-by: Mauricio Vásquez Signed-off-by: Rafael David Tinoco Signed-off-by: Lorenzo Fontana Signed-off-by: Leonardo Di Donato Signed-off-by: Andrii Nakryiko Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220215225856.671072-4-mauricio@kinvolk.io --- tools/bpf/bpftool/bash-completion/bpftool | 6 ++++- tools/bpf/bpftool/gen.c | 42 ++++++++++++++++++++++++++++--- 2 files changed, 44 insertions(+), 4 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/bash-completion/bpftool b/tools/bpf/bpftool/bash-completion/bpftool index 493753a4962e..958e1fd71b5c 100644 --- a/tools/bpf/bpftool/bash-completion/bpftool +++ b/tools/bpf/bpftool/bash-completion/bpftool @@ -1003,9 +1003,13 @@ _bpftool() ;; esac ;; + min_core_btf) + _filedir + return 0 + ;; *) [[ $prev == $object ]] && \ - COMPREPLY=( $( compgen -W 'object skeleton help' -- "$cur" ) ) + COMPREPLY=( $( compgen -W 'object skeleton help min_core_btf' -- "$cur" ) ) ;; esac ;; diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index 022f30490567..8e066c747691 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -1108,6 +1108,7 @@ static int do_help(int argc, char **argv) fprintf(stderr, "Usage: %1$s %2$s object OUTPUT_FILE INPUT_FILE [INPUT_FILE...]\n" " %1$s %2$s skeleton FILE [name OBJECT_NAME]\n" + " %1$s %2$s min_core_btf INPUT OUTPUT OBJECT [OBJECT...]\n" " %1$s %2$s help\n" "\n" " " HELP_SPEC_OPTIONS " |\n" @@ -1118,10 +1119,45 @@ static int do_help(int argc, char **argv) return 0; } +/* Create minimized BTF file for a set of BPF objects */ +static int minimize_btf(const char *src_btf, const char *dst_btf, const char *objspaths[]) +{ + return -EOPNOTSUPP; +} + +static int do_min_core_btf(int argc, char **argv) +{ + const char *input, *output, **objs; + int i, err; + + if (!REQ_ARGS(3)) { + usage(); + return -1; + } + + input = GET_ARG(); + output = GET_ARG(); + + objs = (const char **) calloc(argc + 1, sizeof(*objs)); + if (!objs) { + p_err("failed to allocate array for object names"); + return -ENOMEM; + } + + i = 0; + while (argc) + objs[i++] = GET_ARG(); + + err = minimize_btf(input, output, objs); + free(objs); + return err; +} + static const struct cmd cmds[] = { - { "object", do_object }, - { "skeleton", do_skeleton }, - { "help", do_help }, + { "object", do_object }, + { "skeleton", do_skeleton }, + { "min_core_btf", do_min_core_btf}, + { "help", do_help }, { 0 } }; -- cgit v1.2.3 From a9caaba399f9cff34c6bffa1b1fd673d3d6043a0 Mon Sep 17 00:00:00 2001 From: Mauricio Vásquez Date: Tue, 15 Feb 2022 17:58:53 -0500 Subject: bpftool: Implement "gen min_core_btf" logic MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This commit implements the logic for the gen min_core_btf command. Specifically, it implements the following functions: - minimize_btf(): receives the path of a source and destination BTF files and a list of BPF objects. This function records the relocations for all objects and then generates the BTF file by calling btfgen_get_btf() (implemented in the following commit). - btfgen_record_obj(): loads the BTF and BTF.ext sections of the BPF objects and loops through all CO-RE relocations. It uses bpf_core_calc_relo_insn() from libbpf and passes the target spec to btfgen_record_reloc(), that calls one of the following functions depending on the relocation kind. - btfgen_record_field_relo(): uses the target specification to mark all the types that are involved in a field-based CO-RE relocation. In this case types resolved and marked recursively using btfgen_mark_type(). Only the struct and union members (and their types) involved in the relocation are marked to optimize the size of the generated BTF file. - btfgen_record_type_relo(): marks the types involved in a type-based CO-RE relocation. In this case no members for the struct and union types are marked as libbpf doesn't use them while performing this kind of relocation. Pointed types are marked as they are used by libbpf in this case. - btfgen_record_enumval_relo(): marks the whole enum type for enum-based relocations. Signed-off-by: Mauricio Vásquez Signed-off-by: Rafael David Tinoco Signed-off-by: Lorenzo Fontana Signed-off-by: Leonardo Di Donato Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220215225856.671072-5-mauricio@kinvolk.io --- tools/bpf/bpftool/Makefile | 8 +- tools/bpf/bpftool/gen.c | 455 ++++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 457 insertions(+), 6 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile index 94b2c2f4ad43..a137db96bd56 100644 --- a/tools/bpf/bpftool/Makefile +++ b/tools/bpf/bpftool/Makefile @@ -34,10 +34,10 @@ LIBBPF_BOOTSTRAP_INCLUDE := $(LIBBPF_BOOTSTRAP_DESTDIR)/include LIBBPF_BOOTSTRAP_HDRS_DIR := $(LIBBPF_BOOTSTRAP_INCLUDE)/bpf LIBBPF_BOOTSTRAP := $(LIBBPF_BOOTSTRAP_OUTPUT)libbpf.a -# We need to copy hashmap.h and nlattr.h which is not otherwise exported by -# libbpf, but still required by bpftool. -LIBBPF_INTERNAL_HDRS := $(addprefix $(LIBBPF_HDRS_DIR)/,hashmap.h nlattr.h) -LIBBPF_BOOTSTRAP_INTERNAL_HDRS := $(addprefix $(LIBBPF_BOOTSTRAP_HDRS_DIR)/,hashmap.h) +# We need to copy hashmap.h, nlattr.h, relo_core.h and libbpf_internal.h +# which are not otherwise exported by libbpf, but still required by bpftool. +LIBBPF_INTERNAL_HDRS := $(addprefix $(LIBBPF_HDRS_DIR)/,hashmap.h nlattr.h relo_core.h libbpf_internal.h) +LIBBPF_BOOTSTRAP_INTERNAL_HDRS := $(addprefix $(LIBBPF_BOOTSTRAP_HDRS_DIR)/,hashmap.h relo_core.h libbpf_internal.h) $(LIBBPF_OUTPUT) $(BOOTSTRAP_OUTPUT) $(LIBBPF_BOOTSTRAP_OUTPUT) $(LIBBPF_HDRS_DIR) $(LIBBPF_BOOTSTRAP_HDRS_DIR): $(QUIET_MKDIR)mkdir -p $@ diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index 8e066c747691..806001020841 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -1119,10 +1120,460 @@ static int do_help(int argc, char **argv) return 0; } -/* Create minimized BTF file for a set of BPF objects */ +static int btf_save_raw(const struct btf *btf, const char *path) +{ + const void *data; + FILE *f = NULL; + __u32 data_sz; + int err = 0; + + data = btf__raw_data(btf, &data_sz); + if (!data) + return -ENOMEM; + + f = fopen(path, "wb"); + if (!f) + return -errno; + + if (fwrite(data, 1, data_sz, f) != data_sz) + err = -errno; + + fclose(f); + return err; +} + +struct btfgen_info { + struct btf *src_btf; + struct btf *marked_btf; /* btf structure used to mark used types */ +}; + +static size_t btfgen_hash_fn(const void *key, void *ctx) +{ + return (size_t)key; +} + +static bool btfgen_equal_fn(const void *k1, const void *k2, void *ctx) +{ + return k1 == k2; +} + +static void *u32_as_hash_key(__u32 x) +{ + return (void *)(uintptr_t)x; +} + +static void btfgen_free_info(struct btfgen_info *info) +{ + if (!info) + return; + + btf__free(info->src_btf); + btf__free(info->marked_btf); + + free(info); +} + +static struct btfgen_info * +btfgen_new_info(const char *targ_btf_path) +{ + struct btfgen_info *info; + int err; + + info = calloc(1, sizeof(*info)); + if (!info) + return NULL; + + info->src_btf = btf__parse(targ_btf_path, NULL); + if (!info->src_btf) { + err = -errno; + p_err("failed parsing '%s' BTF file: %s", targ_btf_path, strerror(errno)); + goto err_out; + } + + info->marked_btf = btf__parse(targ_btf_path, NULL); + if (!info->marked_btf) { + err = -errno; + p_err("failed parsing '%s' BTF file: %s", targ_btf_path, strerror(errno)); + goto err_out; + } + + return info; + +err_out: + btfgen_free_info(info); + errno = -err; + return NULL; +} + +#define MARKED UINT32_MAX + +static void btfgen_mark_member(struct btfgen_info *info, int type_id, int idx) +{ + const struct btf_type *t = btf__type_by_id(info->marked_btf, type_id); + struct btf_member *m = btf_members(t) + idx; + + m->name_off = MARKED; +} + +static int +btfgen_mark_type(struct btfgen_info *info, unsigned int type_id, bool follow_pointers) +{ + const struct btf_type *btf_type = btf__type_by_id(info->src_btf, type_id); + struct btf_type *cloned_type; + struct btf_param *param; + struct btf_array *array; + int err, i; + + if (type_id == 0) + return 0; + + /* mark type on cloned BTF as used */ + cloned_type = (struct btf_type *) btf__type_by_id(info->marked_btf, type_id); + cloned_type->name_off = MARKED; + + /* recursively mark other types needed by it */ + switch (btf_kind(btf_type)) { + case BTF_KIND_UNKN: + case BTF_KIND_INT: + case BTF_KIND_FLOAT: + case BTF_KIND_ENUM: + case BTF_KIND_STRUCT: + case BTF_KIND_UNION: + break; + case BTF_KIND_PTR: + if (follow_pointers) { + err = btfgen_mark_type(info, btf_type->type, follow_pointers); + if (err) + return err; + } + break; + case BTF_KIND_CONST: + case BTF_KIND_VOLATILE: + case BTF_KIND_TYPEDEF: + err = btfgen_mark_type(info, btf_type->type, follow_pointers); + if (err) + return err; + break; + case BTF_KIND_ARRAY: + array = btf_array(btf_type); + + /* mark array type */ + err = btfgen_mark_type(info, array->type, follow_pointers); + /* mark array's index type */ + err = err ? : btfgen_mark_type(info, array->index_type, follow_pointers); + if (err) + return err; + break; + case BTF_KIND_FUNC_PROTO: + /* mark ret type */ + err = btfgen_mark_type(info, btf_type->type, follow_pointers); + if (err) + return err; + + /* mark parameters types */ + param = btf_params(btf_type); + for (i = 0; i < btf_vlen(btf_type); i++) { + err = btfgen_mark_type(info, param->type, follow_pointers); + if (err) + return err; + param++; + } + break; + /* tells if some other type needs to be handled */ + default: + p_err("unsupported kind: %s (%d)", btf_kind_str(btf_type), type_id); + return -EINVAL; + } + + return 0; +} + +static int btfgen_record_field_relo(struct btfgen_info *info, struct bpf_core_spec *targ_spec) +{ + struct btf *btf = info->src_btf; + const struct btf_type *btf_type; + struct btf_member *btf_member; + struct btf_array *array; + unsigned int type_id = targ_spec->root_type_id; + int idx, err; + + /* mark root type */ + btf_type = btf__type_by_id(btf, type_id); + err = btfgen_mark_type(info, type_id, false); + if (err) + return err; + + /* mark types for complex types (arrays, unions, structures) */ + for (int i = 1; i < targ_spec->raw_len; i++) { + /* skip typedefs and mods */ + while (btf_is_mod(btf_type) || btf_is_typedef(btf_type)) { + type_id = btf_type->type; + btf_type = btf__type_by_id(btf, type_id); + } + + switch (btf_kind(btf_type)) { + case BTF_KIND_STRUCT: + case BTF_KIND_UNION: + idx = targ_spec->raw_spec[i]; + btf_member = btf_members(btf_type) + idx; + + /* mark member */ + btfgen_mark_member(info, type_id, idx); + + /* mark member's type */ + type_id = btf_member->type; + btf_type = btf__type_by_id(btf, type_id); + err = btfgen_mark_type(info, type_id, false); + if (err) + return err; + break; + case BTF_KIND_ARRAY: + array = btf_array(btf_type); + type_id = array->type; + btf_type = btf__type_by_id(btf, type_id); + break; + default: + p_err("unsupported kind: %s (%d)", + btf_kind_str(btf_type), btf_type->type); + return -EINVAL; + } + } + + return 0; +} + +static int btfgen_record_type_relo(struct btfgen_info *info, struct bpf_core_spec *targ_spec) +{ + return btfgen_mark_type(info, targ_spec->root_type_id, true); +} + +static int btfgen_record_enumval_relo(struct btfgen_info *info, struct bpf_core_spec *targ_spec) +{ + return btfgen_mark_type(info, targ_spec->root_type_id, false); +} + +static int btfgen_record_reloc(struct btfgen_info *info, struct bpf_core_spec *res) +{ + switch (res->relo_kind) { + case BPF_CORE_FIELD_BYTE_OFFSET: + case BPF_CORE_FIELD_BYTE_SIZE: + case BPF_CORE_FIELD_EXISTS: + case BPF_CORE_FIELD_SIGNED: + case BPF_CORE_FIELD_LSHIFT_U64: + case BPF_CORE_FIELD_RSHIFT_U64: + return btfgen_record_field_relo(info, res); + case BPF_CORE_TYPE_ID_LOCAL: /* BPF_CORE_TYPE_ID_LOCAL doesn't require kernel BTF */ + return 0; + case BPF_CORE_TYPE_ID_TARGET: + case BPF_CORE_TYPE_EXISTS: + case BPF_CORE_TYPE_SIZE: + return btfgen_record_type_relo(info, res); + case BPF_CORE_ENUMVAL_EXISTS: + case BPF_CORE_ENUMVAL_VALUE: + return btfgen_record_enumval_relo(info, res); + default: + return -EINVAL; + } +} + +static struct bpf_core_cand_list * +btfgen_find_cands(const struct btf *local_btf, const struct btf *targ_btf, __u32 local_id) +{ + const struct btf_type *local_type; + struct bpf_core_cand_list *cands = NULL; + struct bpf_core_cand local_cand = {}; + size_t local_essent_len; + const char *local_name; + int err; + + local_cand.btf = local_btf; + local_cand.id = local_id; + + local_type = btf__type_by_id(local_btf, local_id); + if (!local_type) { + err = -EINVAL; + goto err_out; + } + + local_name = btf__name_by_offset(local_btf, local_type->name_off); + if (!local_name) { + err = -EINVAL; + goto err_out; + } + local_essent_len = bpf_core_essential_name_len(local_name); + + cands = calloc(1, sizeof(*cands)); + if (!cands) + return NULL; + + err = bpf_core_add_cands(&local_cand, local_essent_len, targ_btf, "vmlinux", 1, cands); + if (err) + goto err_out; + + return cands; + +err_out: + bpf_core_free_cands(cands); + errno = -err; + return NULL; +} + +/* Record relocation information for a single BPF object */ +static int btfgen_record_obj(struct btfgen_info *info, const char *obj_path) +{ + const struct btf_ext_info_sec *sec; + const struct bpf_core_relo *relo; + const struct btf_ext_info *seg; + struct hashmap_entry *entry; + struct hashmap *cand_cache = NULL; + struct btf_ext *btf_ext = NULL; + unsigned int relo_idx; + struct btf *btf = NULL; + size_t i; + int err; + + btf = btf__parse(obj_path, &btf_ext); + if (!btf) { + err = -errno; + p_err("failed to parse BPF object '%s': %s", obj_path, strerror(errno)); + return err; + } + + if (!btf_ext) { + p_err("failed to parse BPF object '%s': section %s not found", + obj_path, BTF_EXT_ELF_SEC); + err = -EINVAL; + goto out; + } + + if (btf_ext->core_relo_info.len == 0) { + err = 0; + goto out; + } + + cand_cache = hashmap__new(btfgen_hash_fn, btfgen_equal_fn, NULL); + if (IS_ERR(cand_cache)) { + err = PTR_ERR(cand_cache); + goto out; + } + + seg = &btf_ext->core_relo_info; + for_each_btf_ext_sec(seg, sec) { + for_each_btf_ext_rec(seg, sec, relo_idx, relo) { + struct bpf_core_spec specs_scratch[3] = {}; + struct bpf_core_relo_res targ_res = {}; + struct bpf_core_cand_list *cands = NULL; + const void *type_key = u32_as_hash_key(relo->type_id); + const char *sec_name = btf__name_by_offset(btf, sec->sec_name_off); + + if (relo->kind != BPF_CORE_TYPE_ID_LOCAL && + !hashmap__find(cand_cache, type_key, (void **)&cands)) { + cands = btfgen_find_cands(btf, info->src_btf, relo->type_id); + if (!cands) { + err = -errno; + goto out; + } + + err = hashmap__set(cand_cache, type_key, cands, NULL, NULL); + if (err) + goto out; + } + + err = bpf_core_calc_relo_insn(sec_name, relo, relo_idx, btf, cands, + specs_scratch, &targ_res); + if (err) + goto out; + + /* specs_scratch[2] is the target spec */ + err = btfgen_record_reloc(info, &specs_scratch[2]); + if (err) + goto out; + } + } + +out: + btf__free(btf); + btf_ext__free(btf_ext); + + if (!IS_ERR_OR_NULL(cand_cache)) { + hashmap__for_each_entry(cand_cache, entry, i) { + bpf_core_free_cands(entry->value); + } + hashmap__free(cand_cache); + } + + return err; +} + +/* Generate BTF from relocation information previously recorded */ +static struct btf *btfgen_get_btf(struct btfgen_info *info) +{ + return ERR_PTR(-EOPNOTSUPP); +} + +/* Create minimized BTF file for a set of BPF objects. + * + * The BTFGen algorithm is divided in two main parts: (1) collect the + * BTF types that are involved in relocations and (2) generate the BTF + * object using the collected types. + * + * In order to collect the types involved in the relocations, we parse + * the BTF and BTF.ext sections of the BPF objects and use + * bpf_core_calc_relo_insn() to get the target specification, this + * indicates how the types and fields are used in a relocation. + * + * Types are recorded in different ways according to the kind of the + * relocation. For field-based relocations only the members that are + * actually used are saved in order to reduce the size of the generated + * BTF file. For type-based relocations empty struct / unions are + * generated and for enum-based relocations the whole type is saved. + * + * The second part of the algorithm generates the BTF object. It creates + * an empty BTF object and fills it with the types recorded in the + * previous step. This function takes care of only adding the structure + * and union members that were marked as used and it also fixes up the + * type IDs on the generated BTF object. + */ static int minimize_btf(const char *src_btf, const char *dst_btf, const char *objspaths[]) { - return -EOPNOTSUPP; + struct btfgen_info *info; + struct btf *btf_new = NULL; + int err, i; + + info = btfgen_new_info(src_btf); + if (!info) { + err = -errno; + p_err("failed to allocate info structure: %s", strerror(errno)); + goto out; + } + + for (i = 0; objspaths[i] != NULL; i++) { + err = btfgen_record_obj(info, objspaths[i]); + if (err) { + p_err("error recording relocations for %s: %s", objspaths[i], + strerror(errno)); + goto out; + } + } + + btf_new = btfgen_get_btf(info); + if (!btf_new) { + err = -errno; + p_err("error generating BTF: %s", strerror(errno)); + goto out; + } + + err = btf_save_raw(btf_new, dst_btf); + if (err) { + p_err("error saving btf file: %s", strerror(errno)); + goto out; + } + +out: + btf__free(btf_new); + btfgen_free_info(info); + + return err; } static int do_min_core_btf(int argc, char **argv) -- cgit v1.2.3 From dc695516b6f5cb322b95de7ef3a6ec1db707ff8b Mon Sep 17 00:00:00 2001 From: Mauricio Vásquez Date: Tue, 15 Feb 2022 17:58:54 -0500 Subject: bpftool: Implement btfgen_get_btf() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The last part of the BTFGen algorithm is to create a new BTF object with all the types that were recorded in the previous steps. This function performs two different steps: 1. Add the types to the new BTF object by using btf__add_type(). Some special logic around struct and unions is implemented to only add the members that are really used in the field-based relocations. The type ID on the new and old BTF objects is stored on a map. 2. Fix all the type IDs on the new BTF object by using the IDs saved in the previous step. Signed-off-by: Mauricio Vásquez Signed-off-by: Rafael David Tinoco Signed-off-by: Lorenzo Fontana Signed-off-by: Leonardo Di Donato Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220215225856.671072-6-mauricio@kinvolk.io --- tools/bpf/bpftool/gen.c | 100 +++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 99 insertions(+), 1 deletion(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index 806001020841..e461059a72ee 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -1505,10 +1505,108 @@ out: return err; } +static int btfgen_remap_id(__u32 *type_id, void *ctx) +{ + unsigned int *ids = ctx; + + *type_id = ids[*type_id]; + + return 0; +} + /* Generate BTF from relocation information previously recorded */ static struct btf *btfgen_get_btf(struct btfgen_info *info) { - return ERR_PTR(-EOPNOTSUPP); + struct btf *btf_new = NULL; + unsigned int *ids = NULL; + unsigned int i, n = btf__type_cnt(info->marked_btf); + int err = 0; + + btf_new = btf__new_empty(); + if (!btf_new) { + err = -errno; + goto err_out; + } + + ids = calloc(n, sizeof(*ids)); + if (!ids) { + err = -errno; + goto err_out; + } + + /* first pass: add all marked types to btf_new and add their new ids to the ids map */ + for (i = 1; i < n; i++) { + const struct btf_type *cloned_type, *type; + const char *name; + int new_id; + + cloned_type = btf__type_by_id(info->marked_btf, i); + + if (cloned_type->name_off != MARKED) + continue; + + type = btf__type_by_id(info->src_btf, i); + + /* add members for struct and union */ + if (btf_is_composite(type)) { + struct btf_member *cloned_m, *m; + unsigned short vlen; + int idx_src; + + name = btf__str_by_offset(info->src_btf, type->name_off); + + if (btf_is_struct(type)) + err = btf__add_struct(btf_new, name, type->size); + else + err = btf__add_union(btf_new, name, type->size); + + if (err < 0) + goto err_out; + new_id = err; + + cloned_m = btf_members(cloned_type); + m = btf_members(type); + vlen = btf_vlen(cloned_type); + for (idx_src = 0; idx_src < vlen; idx_src++, cloned_m++, m++) { + /* add only members that are marked as used */ + if (cloned_m->name_off != MARKED) + continue; + + name = btf__str_by_offset(info->src_btf, m->name_off); + err = btf__add_field(btf_new, name, m->type, + btf_member_bit_offset(cloned_type, idx_src), + btf_member_bitfield_size(cloned_type, idx_src)); + if (err < 0) + goto err_out; + } + } else { + err = btf__add_type(btf_new, info->src_btf, type); + if (err < 0) + goto err_out; + new_id = err; + } + + /* add ID mapping */ + ids[i] = new_id; + } + + /* second pass: fix up type ids */ + for (i = 1; i < btf__type_cnt(btf_new); i++) { + struct btf_type *btf_type = (struct btf_type *) btf__type_by_id(btf_new, i); + + err = btf_type_visit_type_ids(btf_type, btfgen_remap_id, ids); + if (err) + goto err_out; + } + + free(ids); + return btf_new; + +err_out: + btf__free(btf_new); + free(ids); + errno = -err; + return NULL; } /* Create minimized BTF file for a set of BPF objects. -- cgit v1.2.3 From 1d1ffbf7f0b261fd5dcac2cd40a92b9394df08f6 Mon Sep 17 00:00:00 2001 From: Rafael David Tinoco Date: Tue, 15 Feb 2022 17:58:55 -0500 Subject: bpftool: Gen min_core_btf explanation and examples MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add "min_core_btf" feature explanation and one example of how to use it to bpftool-gen man page. Signed-off-by: Mauricio Vásquez Signed-off-by: Rafael David Tinoco Signed-off-by: Lorenzo Fontana Signed-off-by: Leonardo Di Donato Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220215225856.671072-7-mauricio@kinvolk.io --- tools/bpf/bpftool/Documentation/bpftool-gen.rst | 90 +++++++++++++++++++++++++ 1 file changed, 90 insertions(+) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/Documentation/bpftool-gen.rst b/tools/bpf/bpftool/Documentation/bpftool-gen.rst index bc276388f432..18d646b571ec 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-gen.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-gen.rst @@ -25,6 +25,7 @@ GEN COMMANDS | **bpftool** **gen object** *OUTPUT_FILE* *INPUT_FILE* [*INPUT_FILE*...] | **bpftool** **gen skeleton** *FILE* [**name** *OBJECT_NAME*] +| **bpftool** **gen min_core_btf** *INPUT* *OUTPUT* *OBJECT* [*OBJECT*...] | **bpftool** **gen help** DESCRIPTION @@ -149,6 +150,26 @@ DESCRIPTION (non-read-only) data from userspace, with same simplicity as for BPF side. + **bpftool** **gen min_core_btf** *INPUT* *OUTPUT* *OBJECT* [*OBJECT*...] + Generate a minimum BTF file as *OUTPUT*, derived from a given + *INPUT* BTF file, containing all needed BTF types so one, or + more, given eBPF objects CO-RE relocations may be satisfied. + + When kernels aren't compiled with CONFIG_DEBUG_INFO_BTF, + libbpf, when loading an eBPF object, has to rely on external + BTF files to be able to calculate CO-RE relocations. + + Usually, an external BTF file is built from existing kernel + DWARF data using pahole. It contains all the types used by + its respective kernel image and, because of that, is big. + + The min_core_btf feature builds smaller BTF files, customized + to one or multiple eBPF objects, so they can be distributed + together with an eBPF CO-RE based application, turning the + application portable to different kernel versions. + + Check examples bellow for more information how to use it. + **bpftool gen help** Print short help message. @@ -215,7 +236,9 @@ This is example BPF application with two BPF programs and a mix of BPF maps and global variables. Source code is split across two source code files. **$ clang -target bpf -g example1.bpf.c -o example1.bpf.o** + **$ clang -target bpf -g example2.bpf.c -o example2.bpf.o** + **$ bpftool gen object example.bpf.o example1.bpf.o example2.bpf.o** This set of commands compiles *example1.bpf.c* and *example2.bpf.c* @@ -329,3 +352,70 @@ BPF ELF object file *example.bpf.o*. my_static_var: 7 This is a stripped-out version of skeleton generated for above example code. + +min_core_btf +------------ + +**$ bpftool btf dump file 5.4.0-example.btf format raw** + +:: + + [1] INT 'long unsigned int' size=8 bits_offset=0 nr_bits=64 encoding=(none) + [2] CONST '(anon)' type_id=1 + [3] VOLATILE '(anon)' type_id=1 + [4] ARRAY '(anon)' type_id=1 index_type_id=21 nr_elems=2 + [5] PTR '(anon)' type_id=8 + [6] CONST '(anon)' type_id=5 + [7] INT 'char' size=1 bits_offset=0 nr_bits=8 encoding=(none) + [8] CONST '(anon)' type_id=7 + [9] INT 'unsigned int' size=4 bits_offset=0 nr_bits=32 encoding=(none) + + +**$ bpftool btf dump file one.bpf.o format raw** + +:: + + [1] PTR '(anon)' type_id=2 + [2] STRUCT 'trace_event_raw_sys_enter' size=64 vlen=4 + 'ent' type_id=3 bits_offset=0 + 'id' type_id=7 bits_offset=64 + 'args' type_id=9 bits_offset=128 + '__data' type_id=12 bits_offset=512 + [3] STRUCT 'trace_entry' size=8 vlen=4 + 'type' type_id=4 bits_offset=0 + 'flags' type_id=5 bits_offset=16 + 'preempt_count' type_id=5 bits_offset=24 + + +**$ bpftool gen min_core_btf 5.4.0-example.btf 5.4.0-smaller.btf one.bpf.o** + +**$ bpftool btf dump file 5.4.0-smaller.btf format raw** + +:: + + [1] TYPEDEF 'pid_t' type_id=6 + [2] STRUCT 'trace_event_raw_sys_enter' size=64 vlen=1 + 'args' type_id=4 bits_offset=128 + [3] STRUCT 'task_struct' size=9216 vlen=2 + 'pid' type_id=1 bits_offset=17920 + 'real_parent' type_id=7 bits_offset=18048 + [4] ARRAY '(anon)' type_id=5 index_type_id=8 nr_elems=6 + [5] INT 'long unsigned int' size=8 bits_offset=0 nr_bits=64 encoding=(none) + [6] TYPEDEF '__kernel_pid_t' type_id=8 + [7] PTR '(anon)' type_id=3 + [8] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED + + +Now, the "5.4.0-smaller.btf" file may be used by libbpf as an external BTF file +when loading the "one.bpf.o" object into the "5.4.0-example" kernel. Note that +the generated BTF file won't allow other eBPF objects to be loaded, just the +ones given to min_core_btf. + +:: + + LIBBPF_OPTS(bpf_object_open_opts, opts, .btf_custom_path = "5.4.0-smaller.btf"); + struct bpf_object *obj; + + obj = bpf_object__open_file("one.bpf.o", &opts); + + ... -- cgit v1.2.3 From f76d8507d23834f7e56b0fe95c82605e7d7e0efe Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Wed, 16 Feb 2022 10:21:02 +0100 Subject: bpftool: Fix pretty print dump for maps without BTF loaded The commit e5043894b21f ("bpftool: Use libbpf_get_error() to check error") fails to dump map without BTF loaded in pretty mode (-p option). Fixing this by making sure get_map_kv_btf won't fail in case there's no BTF available for the map. Fixes: e5043894b21f ("bpftool: Use libbpf_get_error() to check error") Suggested-by: Andrii Nakryiko Signed-off-by: Jiri Olsa Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220216092102.125448-1-jolsa@kernel.org --- tools/bpf/bpftool/map.c | 31 +++++++++++++++---------------- 1 file changed, 15 insertions(+), 16 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c index 7a341a472ea4..e746642de292 100644 --- a/tools/bpf/bpftool/map.c +++ b/tools/bpf/bpftool/map.c @@ -805,29 +805,30 @@ static int maps_have_btf(int *fds, int nb_fds) static struct btf *btf_vmlinux; -static struct btf *get_map_kv_btf(const struct bpf_map_info *info) +static int get_map_kv_btf(const struct bpf_map_info *info, struct btf **btf) { - struct btf *btf = NULL; + int err = 0; if (info->btf_vmlinux_value_type_id) { if (!btf_vmlinux) { btf_vmlinux = libbpf_find_kernel_btf(); - if (libbpf_get_error(btf_vmlinux)) + err = libbpf_get_error(btf_vmlinux); + if (err) { p_err("failed to get kernel btf"); + return err; + } } - return btf_vmlinux; + *btf = btf_vmlinux; } else if (info->btf_value_type_id) { - int err; - - btf = btf__load_from_kernel_by_id(info->btf_id); - err = libbpf_get_error(btf); - if (err) { + *btf = btf__load_from_kernel_by_id(info->btf_id); + err = libbpf_get_error(*btf); + if (err) p_err("failed to get btf"); - btf = ERR_PTR(err); - } + } else { + *btf = NULL; } - return btf; + return err; } static void free_map_kv_btf(struct btf *btf) @@ -862,8 +863,7 @@ map_dump(int fd, struct bpf_map_info *info, json_writer_t *wtr, prev_key = NULL; if (wtr) { - btf = get_map_kv_btf(info); - err = libbpf_get_error(btf); + err = get_map_kv_btf(info, &btf); if (err) { goto exit_free; } @@ -1054,8 +1054,7 @@ static void print_key_value(struct bpf_map_info *info, void *key, json_writer_t *btf_wtr; struct btf *btf; - btf = get_map_kv_btf(info); - if (libbpf_get_error(btf)) + if (get_map_kv_btf(info, &btf)) return; if (json_output) { -- cgit v1.2.3 From 9b6eb0478dfad3b0e7af6c73523d96826210f4fe Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Wed, 16 Feb 2022 15:35:40 -0800 Subject: bpftool: Fix C++ additions to skeleton Mark C++-specific T::open() and other methods as static inline to avoid symbol redefinition when multiple files use the same skeleton header in an application. Fixes: bb8ffe61ea45 ("bpftool: Add C++-specific open/load/etc skeleton wrappers") Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20220216233540.216642-1-andrii@kernel.org --- tools/bpf/bpftool/gen.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index e461059a72ee..f8c1413523a3 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -834,13 +834,13 @@ static int do_skeleton(int argc, char **argv) \n\ \n\ #ifdef __cplusplus \n\ - static struct %1$s *open(const struct bpf_object_open_opts *opts = nullptr);\n\ - static struct %1$s *open_and_load(); \n\ - static int load(struct %1$s *skel); \n\ - static int attach(struct %1$s *skel); \n\ - static void detach(struct %1$s *skel); \n\ - static void destroy(struct %1$s *skel); \n\ - static const void *elf_bytes(size_t *sz); \n\ + static inline struct %1$s *open(const struct bpf_object_open_opts *opts = nullptr);\n\ + static inline struct %1$s *open_and_load(); \n\ + static inline int load(struct %1$s *skel); \n\ + static inline int attach(struct %1$s *skel); \n\ + static inline void detach(struct %1$s *skel); \n\ + static inline void destroy(struct %1$s *skel); \n\ + static inline const void *elf_bytes(size_t *sz); \n\ #endif /* __cplusplus */ \n\ }; \n\ \n\ -- cgit v1.2.3 From a19df7139440258e02126f1c795ba64932a8e949 Mon Sep 17 00:00:00 2001 From: Mauricio Vásquez Date: Mon, 21 Feb 2022 07:56:17 -0500 Subject: bpftool: Remove usage of reallocarray() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This commit fixes a compilation error on systems with glibc < 2.26 [0]: ``` In file included from main.h:14:0, from gen.c:24: linux/tools/include/tools/libc_compat.h:11:21: error: attempt to use poisoned "reallocarray" static inline void *reallocarray(void *ptr, size_t nmemb, size_t size) ``` This happens because gen.c pulls , and then (through main.h). When COMPAT_NEED_REALLOCARRAY is set, libc_compat.h defines reallocarray() which libbpf_internal.h poisons with a GCC pragma. This commit reuses libbpf_reallocarray() implemented in commit 029258d7b228 ("libbpf: Remove any use of reallocarray() in libbpf"). v1 -> v2: - reuse libbpf_reallocarray() instead of reimplementing it Fixes: a9caaba399f9 ("bpftool: Implement "gen min_core_btf" logic") Reported-by: Quentin Monnet Signed-off-by: Mauricio Vásquez Signed-off-by: Andrii Nakryiko Reviewed-by: Quentin Monnet Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20220221125617.39610-1-mauricio@kinvolk.io [0]: https://lore.kernel.org/bpf/3bf2bd49-9f2d-a2df-5536-bc0dde70a83b@isovalent.com/ --- tools/bpf/bpftool/Makefile | 6 +----- tools/bpf/bpftool/main.h | 2 +- tools/bpf/bpftool/prog.c | 7 ++++--- tools/bpf/bpftool/xlated_dumper.c | 5 +++-- 4 files changed, 9 insertions(+), 11 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile index a137db96bd56..ba647aede0d6 100644 --- a/tools/bpf/bpftool/Makefile +++ b/tools/bpf/bpftool/Makefile @@ -93,7 +93,7 @@ INSTALL ?= install RM ?= rm -f FEATURE_USER = .bpftool -FEATURE_TESTS = libbfd disassembler-four-args reallocarray zlib libcap \ +FEATURE_TESTS = libbfd disassembler-four-args zlib libcap \ clang-bpf-co-re FEATURE_DISPLAY = libbfd disassembler-four-args zlib libcap \ clang-bpf-co-re @@ -118,10 +118,6 @@ ifeq ($(feature-disassembler-four-args), 1) CFLAGS += -DDISASM_FOUR_ARGS_SIGNATURE endif -ifeq ($(feature-reallocarray), 0) -CFLAGS += -DCOMPAT_NEED_REALLOCARRAY -endif - LIBS = $(LIBBPF) -lelf -lz LIBS_BOOTSTRAP = $(LIBBPF_BOOTSTRAP) -lelf -lz ifeq ($(feature-libcap), 1) diff --git a/tools/bpf/bpftool/main.h b/tools/bpf/bpftool/main.h index 0c3840596b5a..0468e5b24bd4 100644 --- a/tools/bpf/bpftool/main.h +++ b/tools/bpf/bpftool/main.h @@ -8,10 +8,10 @@ #undef GCC_VERSION #include #include +#include #include #include #include -#include #include #include diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 92a6f679ef7d..8a52eed19fa2 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include "cfg.h" @@ -1558,9 +1559,9 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) if (fd < 0) goto err_free_reuse_maps; - new_map_replace = reallocarray(map_replace, - old_map_fds + 1, - sizeof(*map_replace)); + new_map_replace = libbpf_reallocarray(map_replace, + old_map_fds + 1, + sizeof(*map_replace)); if (!new_map_replace) { p_err("mem alloc failed"); goto err_free_reuse_maps; diff --git a/tools/bpf/bpftool/xlated_dumper.c b/tools/bpf/bpftool/xlated_dumper.c index f1f32e21d5cd..2d9cd6a7b3c8 100644 --- a/tools/bpf/bpftool/xlated_dumper.c +++ b/tools/bpf/bpftool/xlated_dumper.c @@ -8,6 +8,7 @@ #include #include #include +#include #include "disasm.h" #include "json_writer.h" @@ -32,8 +33,8 @@ void kernel_syms_load(struct dump_data *dd) return; while (fgets(buff, sizeof(buff), fp)) { - tmp = reallocarray(dd->sym_mapping, dd->sym_count + 1, - sizeof(*dd->sym_mapping)); + tmp = libbpf_reallocarray(dd->sym_mapping, dd->sym_count + 1, + sizeof(*dd->sym_mapping)); if (!tmp) { out: free(dd->sym_mapping); -- cgit v1.2.3 From 08d4dba6ae77aaec0e0c79dcfcb0613cb7426b2c Mon Sep 17 00:00:00 2001 From: Delyan Kratunov Date: Wed, 23 Feb 2022 22:01:58 +0000 Subject: bpftool: Bpf skeletons assert type sizes When emitting type declarations in skeletons, bpftool will now also emit static assertions on the size of the data/bss/rodata/etc fields. This ensures that in situations where userspace and kernel types have the same name but differ in size we do not silently produce incorrect results but instead break the build. This was reported in [1] and as expected the repro in [2] fails to build on the new size assert after this change. [1]: Closes: https://github.com/libbpf/libbpf/issues/433 [2]: https://github.com/fuweid/iovisor-bcc-pr-3777 Signed-off-by: Delyan Kratunov Signed-off-by: Andrii Nakryiko Tested-by: Hengqi Chen Acked-by: Hengqi Chen Link: https://lore.kernel.org/bpf/f562455d7b3cf338e59a7976f4690ec5a0057f7f.camel@fb.com --- tools/bpf/bpftool/gen.c | 127 +++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 105 insertions(+), 22 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index f8c1413523a3..145734b4fe41 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -209,15 +209,36 @@ static int codegen_datasec_def(struct bpf_object *obj, return 0; } +static const struct btf_type *find_type_for_map(struct btf *btf, const char *map_ident) +{ + int n = btf__type_cnt(btf), i; + char sec_ident[256]; + + for (i = 1; i < n; i++) { + const struct btf_type *t = btf__type_by_id(btf, i); + const char *name; + + if (!btf_is_datasec(t)) + continue; + + name = btf__str_by_offset(btf, t->name_off); + if (!get_datasec_ident(name, sec_ident, sizeof(sec_ident))) + continue; + + if (strcmp(sec_ident, map_ident) == 0) + return t; + } + return NULL; +} + static int codegen_datasecs(struct bpf_object *obj, const char *obj_name) { struct btf *btf = bpf_object__btf(obj); - int n = btf__type_cnt(btf); struct btf_dump *d; struct bpf_map *map; const struct btf_type *sec; - char sec_ident[256], map_ident[256]; - int i, err = 0; + char map_ident[256]; + int err = 0; d = btf_dump__new(btf, codegen_btf_dump_printf, NULL, NULL); err = libbpf_get_error(d); @@ -234,23 +255,7 @@ static int codegen_datasecs(struct bpf_object *obj, const char *obj_name) if (!get_map_ident(map, map_ident, sizeof(map_ident))) continue; - sec = NULL; - for (i = 1; i < n; i++) { - const struct btf_type *t = btf__type_by_id(btf, i); - const char *name; - - if (!btf_is_datasec(t)) - continue; - - name = btf__str_by_offset(btf, t->name_off); - if (!get_datasec_ident(name, sec_ident, sizeof(sec_ident))) - continue; - - if (strcmp(sec_ident, map_ident) == 0) { - sec = t; - break; - } - } + sec = find_type_for_map(btf, map_ident); /* In some cases (e.g., sections like .rodata.cst16 containing * compiler allocated string constants only) there will be @@ -363,6 +368,73 @@ static size_t bpf_map_mmap_sz(const struct bpf_map *map) return map_sz; } +/* Emit type size asserts for all top-level fields in memory-mapped internal maps. */ +static void codegen_asserts(struct bpf_object *obj, const char *obj_name) +{ + struct btf *btf = bpf_object__btf(obj); + struct bpf_map *map; + struct btf_var_secinfo *sec_var; + int i, vlen; + const struct btf_type *sec; + char map_ident[256], var_ident[256]; + + codegen("\ + \n\ + __attribute__((unused)) static void \n\ + %1$s__assert(struct %1$s *s) \n\ + { \n\ + #ifdef __cplusplus \n\ + #define _Static_assert static_assert \n\ + #endif \n\ + ", obj_name); + + bpf_object__for_each_map(map, obj) { + if (!bpf_map__is_internal(map)) + continue; + if (!(bpf_map__map_flags(map) & BPF_F_MMAPABLE)) + continue; + if (!get_map_ident(map, map_ident, sizeof(map_ident))) + continue; + + sec = find_type_for_map(btf, map_ident); + if (!sec) { + /* best effort, couldn't find the type for this map */ + continue; + } + + sec_var = btf_var_secinfos(sec); + vlen = btf_vlen(sec); + + for (i = 0; i < vlen; i++, sec_var++) { + const struct btf_type *var = btf__type_by_id(btf, sec_var->type); + const char *var_name = btf__name_by_offset(btf, var->name_off); + long var_size; + + /* static variables are not exposed through BPF skeleton */ + if (btf_var(var)->linkage == BTF_VAR_STATIC) + continue; + + var_size = btf__resolve_size(btf, var->type); + if (var_size < 0) + continue; + + var_ident[0] = '\0'; + strncat(var_ident, var_name, sizeof(var_ident) - 1); + sanitize_identifier(var_ident); + + printf("\t_Static_assert(sizeof(s->%s->%s) == %ld, \"unexpected size of '%s'\");\n", + map_ident, var_ident, var_size, var_ident); + } + } + codegen("\ + \n\ + #ifdef __cplusplus \n\ + #undef _Static_assert \n\ + #endif \n\ + } \n\ + "); +} + static void codegen_attach_detach(struct bpf_object *obj, const char *obj_name) { struct bpf_program *prog; @@ -639,8 +711,11 @@ static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h } \n\ return skel; \n\ } \n\ + \n\ ", obj_name); + codegen_asserts(obj, obj_name); + codegen("\ \n\ \n\ @@ -1046,9 +1121,17 @@ static int do_skeleton(int argc, char **argv) const void *%1$s::elf_bytes(size_t *sz) { return %1$s__elf_bytes(sz); } \n\ #endif /* __cplusplus */ \n\ \n\ - #endif /* %2$s */ \n\ ", - obj_name, header_guard); + obj_name); + + codegen_asserts(obj, obj_name); + + codegen("\ + \n\ + \n\ + #endif /* %1$s */ \n\ + ", + header_guard); err = 0; out: bpf_object__close(obj); -- cgit v1.2.3 From c62dd8a58d19fa35b60c84ab2435ac3ad0d3777e Mon Sep 17 00:00:00 2001 From: Yuntao Wang Date: Sun, 27 Feb 2022 00:38:15 +0800 Subject: bpftool: Remove redundant slashes Because the OUTPUT variable ends with a slash but CURDIR doesn't, to keep the _OUTPUT value consistent, we add a trailing slash to CURDIR when defining _OUTPUT variable. Since the _OUTPUT variable holds a value ending with a trailing slash, there is no need to add another one when defining BOOTSTRAP_OUTPUT and LIBBPF_OUTPUT variables. Likewise, when defining LIBBPF_INCLUDE and LIBBPF_BOOTSTRAP_INCLUDE, we shouldn't add an extra slash either for the same reason. When building libbpf, the value of the DESTDIR argument should also not end with a trailing slash. Signed-off-by: Yuntao Wang Signed-off-by: Daniel Borkmann Reviewed-by: Quentin Monnet Link: https://lore.kernel.org/bpf/20220226163815.520133-1-ytcoode@gmail.com --- tools/bpf/bpftool/Makefile | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile index ba647aede0d6..9800f966fd51 100644 --- a/tools/bpf/bpftool/Makefile +++ b/tools/bpf/bpftool/Makefile @@ -18,19 +18,19 @@ BPF_DIR = $(srctree)/tools/lib/bpf ifneq ($(OUTPUT),) _OUTPUT := $(OUTPUT) else - _OUTPUT := $(CURDIR) + _OUTPUT := $(CURDIR)/ endif -BOOTSTRAP_OUTPUT := $(_OUTPUT)/bootstrap/ +BOOTSTRAP_OUTPUT := $(_OUTPUT)bootstrap/ -LIBBPF_OUTPUT := $(_OUTPUT)/libbpf/ +LIBBPF_OUTPUT := $(_OUTPUT)libbpf/ LIBBPF_DESTDIR := $(LIBBPF_OUTPUT) -LIBBPF_INCLUDE := $(LIBBPF_DESTDIR)/include +LIBBPF_INCLUDE := $(LIBBPF_DESTDIR)include LIBBPF_HDRS_DIR := $(LIBBPF_INCLUDE)/bpf LIBBPF := $(LIBBPF_OUTPUT)libbpf.a LIBBPF_BOOTSTRAP_OUTPUT := $(BOOTSTRAP_OUTPUT)libbpf/ LIBBPF_BOOTSTRAP_DESTDIR := $(LIBBPF_BOOTSTRAP_OUTPUT) -LIBBPF_BOOTSTRAP_INCLUDE := $(LIBBPF_BOOTSTRAP_DESTDIR)/include +LIBBPF_BOOTSTRAP_INCLUDE := $(LIBBPF_BOOTSTRAP_DESTDIR)include LIBBPF_BOOTSTRAP_HDRS_DIR := $(LIBBPF_BOOTSTRAP_INCLUDE)/bpf LIBBPF_BOOTSTRAP := $(LIBBPF_BOOTSTRAP_OUTPUT)libbpf.a @@ -44,7 +44,7 @@ $(LIBBPF_OUTPUT) $(BOOTSTRAP_OUTPUT) $(LIBBPF_BOOTSTRAP_OUTPUT) $(LIBBPF_HDRS_DI $(LIBBPF): $(wildcard $(BPF_DIR)/*.[ch] $(BPF_DIR)/Makefile) | $(LIBBPF_OUTPUT) $(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(LIBBPF_OUTPUT) \ - DESTDIR=$(LIBBPF_DESTDIR) prefix= $(LIBBPF) install_headers + DESTDIR=$(LIBBPF_DESTDIR:/=) prefix= $(LIBBPF) install_headers $(LIBBPF_INTERNAL_HDRS): $(LIBBPF_HDRS_DIR)/%.h: $(BPF_DIR)/%.h | $(LIBBPF_HDRS_DIR) $(call QUIET_INSTALL, $@) @@ -52,7 +52,7 @@ $(LIBBPF_INTERNAL_HDRS): $(LIBBPF_HDRS_DIR)/%.h: $(BPF_DIR)/%.h | $(LIBBPF_HDRS_ $(LIBBPF_BOOTSTRAP): $(wildcard $(BPF_DIR)/*.[ch] $(BPF_DIR)/Makefile) | $(LIBBPF_BOOTSTRAP_OUTPUT) $(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(LIBBPF_BOOTSTRAP_OUTPUT) \ - DESTDIR=$(LIBBPF_BOOTSTRAP_DESTDIR) prefix= \ + DESTDIR=$(LIBBPF_BOOTSTRAP_DESTDIR:/=) prefix= \ ARCH= CROSS_COMPILE= CC=$(HOSTCC) LD=$(HOSTLD) $@ install_headers $(LIBBPF_BOOTSTRAP_INTERNAL_HDRS): $(LIBBPF_BOOTSTRAP_HDRS_DIR)/%.h: $(BPF_DIR)/%.h | $(LIBBPF_BOOTSTRAP_HDRS_DIR) -- cgit v1.2.3 From f655c088e74f4681134f650b5743174586a61016 Mon Sep 17 00:00:00 2001 From: Niklas Söderlund Date: Thu, 10 Mar 2022 13:18:46 +0100 Subject: bpftool: Restore support for BPF offload-enabled feature probing MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Commit 1a56c18e6c2e4e74 ("bpftool: Stop supporting BPF offload-enabled feature probing") removed the support to probe for BPF offload features. This is still something that is useful for NFP NIC that can support offloading of BPF programs. The reason for the dropped support was that libbpf starting with v1.0 would drop support for passing the ifindex to the BPF prog/map/helper feature probing APIs. In order to keep this useful feature for NFP restore the functionality by moving it directly into bpftool. The code restored is a simplified version of the code that existed in libbpf which supposed passing the ifindex. The simplification is that it only targets the cases where ifindex is given and call into libbpf for the cases where it's not. Before restoring support for probing offload features: # bpftool feature probe dev ens4np0 Scanning system call availability... bpf() syscall is available Scanning eBPF program types... Scanning eBPF map types... Scanning eBPF helper functions... eBPF helpers supported for program type sched_cls: eBPF helpers supported for program type xdp: Scanning miscellaneous eBPF features... Large program size limit is NOT available Bounded loop support is NOT available ISA extension v2 is NOT available ISA extension v3 is NOT available With support for probing offload features restored: # bpftool feature probe dev ens4np0 Scanning system call availability... bpf() syscall is available Scanning eBPF program types... eBPF program_type sched_cls is available eBPF program_type xdp is available Scanning eBPF map types... eBPF map_type hash is available eBPF map_type array is available Scanning eBPF helper functions... eBPF helpers supported for program type sched_cls: - bpf_map_lookup_elem - bpf_get_prandom_u32 - bpf_perf_event_output eBPF helpers supported for program type xdp: - bpf_map_lookup_elem - bpf_get_prandom_u32 - bpf_perf_event_output - bpf_xdp_adjust_head - bpf_xdp_adjust_tail Scanning miscellaneous eBPF features... Large program size limit is NOT available Bounded loop support is NOT available ISA extension v2 is NOT available ISA extension v3 is NOT available Signed-off-by: Niklas Söderlund Signed-off-by: Simon Horman Signed-off-by: Daniel Borkmann Reviewed-by: Quentin Monnet Link: https://lore.kernel.org/bpf/20220310121846.921256-1-niklas.soderlund@corigine.com --- tools/bpf/bpftool/feature.c | 152 ++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 139 insertions(+), 13 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/feature.c b/tools/bpf/bpftool/feature.c index 9c894b1447de..c2f43a5d38e0 100644 --- a/tools/bpf/bpftool/feature.c +++ b/tools/bpf/bpftool/feature.c @@ -3,6 +3,7 @@ #include #include +#include #include #include #include @@ -45,6 +46,11 @@ static bool run_as_unprivileged; /* Miscellaneous utility functions */ +static bool grep(const char *buffer, const char *pattern) +{ + return !!strstr(buffer, pattern); +} + static bool check_procfs(void) { struct statfs st_fs; @@ -135,6 +141,32 @@ static void print_end_section(void) /* Probing functions */ +static int get_vendor_id(int ifindex) +{ + char ifname[IF_NAMESIZE], path[64], buf[8]; + ssize_t len; + int fd; + + if (!if_indextoname(ifindex, ifname)) + return -1; + + snprintf(path, sizeof(path), "/sys/class/net/%s/device/vendor", ifname); + + fd = open(path, O_RDONLY | O_CLOEXEC); + if (fd < 0) + return -1; + + len = read(fd, buf, sizeof(buf)); + close(fd); + if (len < 0) + return -1; + if (len >= (ssize_t)sizeof(buf)) + return -1; + buf[len] = '\0'; + + return strtol(buf, NULL, 0); +} + static int read_procfs(const char *path) { char *endptr, *line = NULL; @@ -478,6 +510,40 @@ static bool probe_bpf_syscall(const char *define_prefix) return res; } +static bool +probe_prog_load_ifindex(enum bpf_prog_type prog_type, + const struct bpf_insn *insns, size_t insns_cnt, + char *log_buf, size_t log_buf_sz, + __u32 ifindex) +{ + LIBBPF_OPTS(bpf_prog_load_opts, opts, + .log_buf = log_buf, + .log_size = log_buf_sz, + .log_level = log_buf ? 1 : 0, + .prog_ifindex = ifindex, + ); + int fd; + + errno = 0; + fd = bpf_prog_load(prog_type, NULL, "GPL", insns, insns_cnt, &opts); + if (fd >= 0) + close(fd); + + return fd >= 0 && errno != EINVAL && errno != EOPNOTSUPP; +} + +static bool probe_prog_type_ifindex(enum bpf_prog_type prog_type, __u32 ifindex) +{ + /* nfp returns -EINVAL on exit(0) with TC offload */ + struct bpf_insn insns[2] = { + BPF_MOV64_IMM(BPF_REG_0, 2), + BPF_EXIT_INSN() + }; + + return probe_prog_load_ifindex(prog_type, insns, ARRAY_SIZE(insns), + NULL, 0, ifindex); +} + static void probe_prog_type(enum bpf_prog_type prog_type, bool *supported_types, const char *define_prefix, __u32 ifindex) @@ -488,11 +554,19 @@ probe_prog_type(enum bpf_prog_type prog_type, bool *supported_types, bool res; if (ifindex) { - p_info("BPF offload feature probing is not supported"); - return; + switch (prog_type) { + case BPF_PROG_TYPE_SCHED_CLS: + case BPF_PROG_TYPE_XDP: + break; + default: + return; + } + + res = probe_prog_type_ifindex(prog_type, ifindex); + } else { + res = libbpf_probe_bpf_prog_type(prog_type, NULL); } - res = libbpf_probe_bpf_prog_type(prog_type, NULL); #ifdef USE_LIBCAP /* Probe may succeed even if program load fails, for unprivileged users * check that we did not fail because of insufficient permissions @@ -521,6 +595,26 @@ probe_prog_type(enum bpf_prog_type prog_type, bool *supported_types, define_prefix); } +static bool probe_map_type_ifindex(enum bpf_map_type map_type, __u32 ifindex) +{ + LIBBPF_OPTS(bpf_map_create_opts, opts); + int key_size, value_size, max_entries; + int fd; + + opts.map_ifindex = ifindex; + + key_size = sizeof(__u32); + value_size = sizeof(__u32); + max_entries = 1; + + fd = bpf_map_create(map_type, NULL, key_size, value_size, max_entries, + &opts); + if (fd >= 0) + close(fd); + + return fd >= 0; +} + static void probe_map_type(enum bpf_map_type map_type, const char *define_prefix, __u32 ifindex) @@ -531,11 +625,18 @@ probe_map_type(enum bpf_map_type map_type, const char *define_prefix, bool res; if (ifindex) { - p_info("BPF offload feature probing is not supported"); - return; - } + switch (map_type) { + case BPF_MAP_TYPE_HASH: + case BPF_MAP_TYPE_ARRAY: + break; + default: + return; + } - res = libbpf_probe_bpf_map_type(map_type, NULL); + res = probe_map_type_ifindex(map_type, ifindex); + } else { + res = libbpf_probe_bpf_map_type(map_type, NULL); + } /* Probe result depends on the success of map creation, no additional * check required for unprivileged users @@ -559,6 +660,33 @@ probe_map_type(enum bpf_map_type map_type, const char *define_prefix, define_prefix); } +static bool +probe_helper_ifindex(enum bpf_func_id id, enum bpf_prog_type prog_type, + __u32 ifindex) +{ + struct bpf_insn insns[2] = { + BPF_EMIT_CALL(id), + BPF_EXIT_INSN() + }; + char buf[4096] = {}; + bool res; + + probe_prog_load_ifindex(prog_type, insns, ARRAY_SIZE(insns), buf, + sizeof(buf), ifindex); + res = !grep(buf, "invalid func ") && !grep(buf, "unknown func "); + + switch (get_vendor_id(ifindex)) { + case 0x19ee: /* Netronome specific */ + res = res && !grep(buf, "not supported by FW") && + !grep(buf, "unsupported function id"); + break; + default: + break; + } + + return res; +} + static void probe_helper_for_progtype(enum bpf_prog_type prog_type, bool supported_type, const char *define_prefix, unsigned int id, @@ -567,12 +695,10 @@ probe_helper_for_progtype(enum bpf_prog_type prog_type, bool supported_type, bool res = false; if (supported_type) { - if (ifindex) { - p_info("BPF offload feature probing is not supported"); - return; - } - - res = libbpf_probe_bpf_helper(prog_type, id, NULL); + if (ifindex) + res = probe_helper_ifindex(id, prog_type, ifindex); + else + res = libbpf_probe_bpf_helper(prog_type, id, NULL); #ifdef USE_LIBCAP /* Probe may succeed even if program load fails, for * unprivileged users check that we did not fail because of -- cgit v1.2.3 From 357b3cc3c0467b2f7cd6c4a87f7a18bfd779ce5b Mon Sep 17 00:00:00 2001 From: Chris J Arges Date: Wed, 9 Mar 2022 15:41:58 -0600 Subject: bpftool: Ensure bytes_memlock json output is correct If a BPF map is created over 2^32 the memlock value as displayed in JSON format will be incorrect. Use atoll instead of atoi so that the correct number is displayed. ``` $ bpftool map create /sys/fs/bpf/test_bpfmap type hash key 4 \ value 1024 entries 4194304 name test_bpfmap $ bpftool map list 1: hash name test_bpfmap flags 0x0 key 4B value 1024B max_entries 4194304 memlock 4328521728B $ sudo bpftool map list -j | jq .[].bytes_memlock 33554432 ``` Signed-off-by: Chris J Arges Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/b6601087-0b11-33cc-904a-1133d1500a10@cloudflare.com --- tools/bpf/bpftool/map.c | 2 +- tools/bpf/bpftool/prog.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c index e746642de292..f91d9bf9054e 100644 --- a/tools/bpf/bpftool/map.c +++ b/tools/bpf/bpftool/map.c @@ -504,7 +504,7 @@ static int show_map_close_json(int fd, struct bpf_map_info *info) jsonw_uint_field(json_wtr, "max_entries", info->max_entries); if (memlock) - jsonw_int_field(json_wtr, "bytes_memlock", atoi(memlock)); + jsonw_int_field(json_wtr, "bytes_memlock", atoll(memlock)); free(memlock); if (info->type == BPF_MAP_TYPE_PROG_ARRAY) { diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 8a52eed19fa2..bc4e05542c2b 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -485,7 +485,7 @@ static void print_prog_json(struct bpf_prog_info *info, int fd) memlock = get_fdinfo(fd, "memlock"); if (memlock) - jsonw_int_field(json_wtr, "bytes_memlock", atoi(memlock)); + jsonw_int_field(json_wtr, "bytes_memlock", atoll(memlock)); free(memlock); if (info->nr_map_ids) -- cgit v1.2.3 From cbdaf71f7e65a45d6e96378ee7bfe3da39c30908 Mon Sep 17 00:00:00 2001 From: Dmitrii Dolgov <9erthalion6@gmail.com> Date: Wed, 9 Mar 2022 17:31:12 +0100 Subject: bpftool: Add bpf_cookie to link output Commit 82e6b1eee6a8 ("bpf: Allow to specify user-provided bpf_cookie for BPF perf links") introduced the concept of user specified bpf_cookie, which could be accessed by BPF programs using bpf_get_attach_cookie(). For troubleshooting purposes it is convenient to expose bpf_cookie via bpftool as well, so there is no need to meddle with the target BPF program itself. Implemented using the pid iterator BPF program to actually fetch bpf_cookies, which allows constraining code changes only to bpftool. $ bpftool link 1: type 7 prog 5 bpf_cookie 123 pids bootstrap(81) Signed-off-by: Dmitrii Dolgov <9erthalion6@gmail.com> Signed-off-by: Andrii Nakryiko Acked-by: Yonghong Song Acked-by: Quentin Monnet Link: https://lore.kernel.org/bpf/20220309163112.24141-1-9erthalion6@gmail.com --- tools/bpf/bpftool/main.h | 2 ++ tools/bpf/bpftool/pids.c | 8 ++++++++ tools/bpf/bpftool/skeleton/pid_iter.bpf.c | 22 ++++++++++++++++++++++ tools/bpf/bpftool/skeleton/pid_iter.h | 2 ++ 4 files changed, 34 insertions(+) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/main.h b/tools/bpf/bpftool/main.h index 0468e5b24bd4..6e9277ffc68c 100644 --- a/tools/bpf/bpftool/main.h +++ b/tools/bpf/bpftool/main.h @@ -113,7 +113,9 @@ struct obj_ref { struct obj_refs { int ref_cnt; + bool has_bpf_cookie; struct obj_ref *refs; + __u64 bpf_cookie; }; struct btf; diff --git a/tools/bpf/bpftool/pids.c b/tools/bpf/bpftool/pids.c index 7c384d10e95f..bb6c969a114a 100644 --- a/tools/bpf/bpftool/pids.c +++ b/tools/bpf/bpftool/pids.c @@ -78,6 +78,8 @@ static void add_ref(struct hashmap *map, struct pid_iter_entry *e) ref->pid = e->pid; memcpy(ref->comm, e->comm, sizeof(ref->comm)); refs->ref_cnt = 1; + refs->has_bpf_cookie = e->has_bpf_cookie; + refs->bpf_cookie = e->bpf_cookie; err = hashmap__append(map, u32_as_hash_field(e->id), refs); if (err) @@ -205,6 +207,9 @@ void emit_obj_refs_json(struct hashmap *map, __u32 id, if (refs->ref_cnt == 0) break; + if (refs->has_bpf_cookie) + jsonw_lluint_field(json_writer, "bpf_cookie", refs->bpf_cookie); + jsonw_name(json_writer, "pids"); jsonw_start_array(json_writer); for (i = 0; i < refs->ref_cnt; i++) { @@ -234,6 +239,9 @@ void emit_obj_refs_plain(struct hashmap *map, __u32 id, const char *prefix) if (refs->ref_cnt == 0) break; + if (refs->has_bpf_cookie) + printf("\n\tbpf_cookie %llu", (unsigned long long) refs->bpf_cookie); + printf("%s", prefix); for (i = 0; i < refs->ref_cnt; i++) { struct obj_ref *ref = &refs->refs[i]; diff --git a/tools/bpf/bpftool/skeleton/pid_iter.bpf.c b/tools/bpf/bpftool/skeleton/pid_iter.bpf.c index f70702fcb224..eb05ea53afb1 100644 --- a/tools/bpf/bpftool/skeleton/pid_iter.bpf.c +++ b/tools/bpf/bpftool/skeleton/pid_iter.bpf.c @@ -38,6 +38,17 @@ static __always_inline __u32 get_obj_id(void *ent, enum bpf_obj_type type) } } +/* could be used only with BPF_LINK_TYPE_PERF_EVENT links */ +static __u64 get_bpf_cookie(struct bpf_link *link) +{ + struct bpf_perf_link *perf_link; + struct perf_event *event; + + perf_link = container_of(link, struct bpf_perf_link, link); + event = BPF_CORE_READ(perf_link, perf_file, private_data); + return BPF_CORE_READ(event, bpf_cookie); +} + SEC("iter/task_file") int iter(struct bpf_iter__task_file *ctx) { @@ -69,8 +80,19 @@ int iter(struct bpf_iter__task_file *ctx) if (file->f_op != fops) return 0; + __builtin_memset(&e, 0, sizeof(e)); e.pid = task->tgid; e.id = get_obj_id(file->private_data, obj_type); + + if (obj_type == BPF_OBJ_LINK) { + struct bpf_link *link = (struct bpf_link *) file->private_data; + + if (BPF_CORE_READ(link, type) == BPF_LINK_TYPE_PERF_EVENT) { + e.has_bpf_cookie = true; + e.bpf_cookie = get_bpf_cookie(link); + } + } + bpf_probe_read_kernel_str(&e.comm, sizeof(e.comm), task->group_leader->comm); bpf_seq_write(ctx->meta->seq, &e, sizeof(e)); diff --git a/tools/bpf/bpftool/skeleton/pid_iter.h b/tools/bpf/bpftool/skeleton/pid_iter.h index 5692cf257adb..bbb570d4cca6 100644 --- a/tools/bpf/bpftool/skeleton/pid_iter.h +++ b/tools/bpf/bpftool/skeleton/pid_iter.h @@ -6,6 +6,8 @@ struct pid_iter_entry { __u32 id; int pid; + __u64 bpf_cookie; + bool has_bpf_cookie; char comm[16]; }; -- cgit v1.2.3 From 6585abea98ae5f750358a6427f2ddf7715393f69 Mon Sep 17 00:00:00 2001 From: Daniel Xu Date: Sun, 13 Mar 2022 16:19:46 -0700 Subject: bpftool: man: Add missing top level docs The top-level (bpftool.8) man page was missing docs for a few subcommands and their respective sub-sub-commands. This commit brings the top level man page up to date. Note that I've kept the ordering of the subcommands the same as in `bpftool help`. Signed-off-by: Daniel Xu Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/3049ef5dc509c0d1832f0a8b2dba2ccaad0af688.1647213551.git.dxu@dxuuu.xyz --- tools/bpf/bpftool/Documentation/bpftool.rst | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/Documentation/bpftool.rst b/tools/bpf/bpftool/Documentation/bpftool.rst index 7084dd9fa2f8..6965c94dfdaf 100644 --- a/tools/bpf/bpftool/Documentation/bpftool.rst +++ b/tools/bpf/bpftool/Documentation/bpftool.rst @@ -20,7 +20,8 @@ SYNOPSIS **bpftool** **version** - *OBJECT* := { **map** | **program** | **cgroup** | **perf** | **net** | **feature** } + *OBJECT* := { **map** | **program** | **link** | **cgroup** | **perf** | **net** | **feature** | + **btf** | **gen** | **struct_ops** | **iter** } *OPTIONS* := { { **-V** | **--version** } | |COMMON_OPTIONS| } @@ -31,6 +32,8 @@ SYNOPSIS *PROG-COMMANDS* := { **show** | **list** | **dump jited** | **dump xlated** | **pin** | **load** | **attach** | **detach** | **help** } + *LINK-COMMANDS* := { **show** | **list** | **pin** | **detach** | **help** } + *CGROUP-COMMANDS* := { **show** | **list** | **attach** | **detach** | **help** } *PERF-COMMANDS* := { **show** | **list** | **help** } @@ -39,6 +42,14 @@ SYNOPSIS *FEATURE-COMMANDS* := { **probe** | **help** } + *BTF-COMMANDS* := { **show** | **list** | **dump** | **help** } + + *GEN-COMMANDS* := { **object** | **skeleton** | **min_core_btf** | **help** } + + *STRUCT-OPS-COMMANDS* := { **show** | **list** | **dump** | **register** | **unregister** | **help** } + + *ITER-COMMANDS* := { **pin** | **help** } + DESCRIPTION =========== *bpftool* allows for inspection and simple modification of BPF objects -- cgit v1.2.3 From 00389c58ffe993782a8ba4bb5a34a102b1f6fe24 Mon Sep 17 00:00:00 2001 From: Delyan Kratunov Date: Wed, 16 Mar 2022 23:37:28 +0000 Subject: bpftool: Add support for subskeletons Subskeletons are headers which require an already loaded program to operate. For example, when a BPF library is linked into a larger BPF object file, the library userspace needs a way to access its own global variables without requiring knowledge about the larger program at build time. As a result, subskeletons require a loaded bpf_object to open(). Further, they find their own symbols in the larger program by walking BTF type data at run time. At this time, programs, maps, and globals are supported through non-owning pointers. Signed-off-by: Delyan Kratunov Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/ca8a48b4841c72d285ecce82371bef4a899756cb.1647473511.git.delyank@fb.com --- tools/bpf/bpftool/Documentation/bpftool-gen.rst | 25 + tools/bpf/bpftool/bash-completion/bpftool | 14 +- tools/bpf/bpftool/gen.c | 588 ++++++++++++++++++++---- 3 files changed, 542 insertions(+), 85 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/Documentation/bpftool-gen.rst b/tools/bpf/bpftool/Documentation/bpftool-gen.rst index 18d646b571ec..68454ef28f58 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-gen.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-gen.rst @@ -25,6 +25,7 @@ GEN COMMANDS | **bpftool** **gen object** *OUTPUT_FILE* *INPUT_FILE* [*INPUT_FILE*...] | **bpftool** **gen skeleton** *FILE* [**name** *OBJECT_NAME*] +| **bpftool** **gen subskeleton** *FILE* [**name** *OBJECT_NAME*] | **bpftool** **gen min_core_btf** *INPUT* *OUTPUT* *OBJECT* [*OBJECT*...] | **bpftool** **gen help** @@ -150,6 +151,30 @@ DESCRIPTION (non-read-only) data from userspace, with same simplicity as for BPF side. + **bpftool gen subskeleton** *FILE* + Generate BPF subskeleton C header file for a given *FILE*. + + Subskeletons are similar to skeletons, except they do not own + the corresponding maps, programs, or global variables. They + require that the object file used to generate them is already + loaded into a *bpf_object* by some other means. + + This functionality is useful when a library is included into a + larger BPF program. A subskeleton for the library would have + access to all objects and globals defined in it, without + having to know about the larger program. + + Consequently, there are only two functions defined + for subskeletons: + + - **example__open(bpf_object\*)** + Instantiates a subskeleton from an already opened (but not + necessarily loaded) **bpf_object**. + + - **example__destroy()** + Frees the storage for the subskeleton but *does not* unload + any BPF programs or maps. + **bpftool** **gen min_core_btf** *INPUT* *OUTPUT* *OBJECT* [*OBJECT*...] Generate a minimum BTF file as *OUTPUT*, derived from a given *INPUT* BTF file, containing all needed BTF types so one, or diff --git a/tools/bpf/bpftool/bash-completion/bpftool b/tools/bpf/bpftool/bash-completion/bpftool index 958e1fd71b5c..5df8d72c5179 100644 --- a/tools/bpf/bpftool/bash-completion/bpftool +++ b/tools/bpf/bpftool/bash-completion/bpftool @@ -1003,13 +1003,25 @@ _bpftool() ;; esac ;; + subskeleton) + case $prev in + $command) + _filedir + return 0 + ;; + *) + _bpftool_once_attr 'name' + return 0 + ;; + esac + ;; min_core_btf) _filedir return 0 ;; *) [[ $prev == $object ]] && \ - COMPREPLY=( $( compgen -W 'object skeleton help min_core_btf' -- "$cur" ) ) + COMPREPLY=( $( compgen -W 'object skeleton subskeleton help min_core_btf' -- "$cur" ) ) ;; esac ;; diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index 145734b4fe41..96bd2b33ccf6 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -64,11 +64,11 @@ static void get_obj_name(char *name, const char *file) sanitize_identifier(name); } -static void get_header_guard(char *guard, const char *obj_name) +static void get_header_guard(char *guard, const char *obj_name, const char *suffix) { int i; - sprintf(guard, "__%s_SKEL_H__", obj_name); + sprintf(guard, "__%s_%s__", obj_name, suffix); for (i = 0; guard[i]; i++) guard[i] = toupper(guard[i]); } @@ -231,6 +231,17 @@ static const struct btf_type *find_type_for_map(struct btf *btf, const char *map return NULL; } +static bool is_internal_mmapable_map(const struct bpf_map *map, char *buf, size_t sz) +{ + if (!bpf_map__is_internal(map) || !(bpf_map__map_flags(map) & BPF_F_MMAPABLE)) + return false; + + if (!get_map_ident(map, buf, sz)) + return false; + + return true; +} + static int codegen_datasecs(struct bpf_object *obj, const char *obj_name) { struct btf *btf = bpf_object__btf(obj); @@ -247,12 +258,7 @@ static int codegen_datasecs(struct bpf_object *obj, const char *obj_name) bpf_object__for_each_map(map, obj) { /* only generate definitions for memory-mapped internal maps */ - if (!bpf_map__is_internal(map)) - continue; - if (!(bpf_map__map_flags(map) & BPF_F_MMAPABLE)) - continue; - - if (!get_map_ident(map, map_ident, sizeof(map_ident))) + if (!is_internal_mmapable_map(map, map_ident, sizeof(map_ident))) continue; sec = find_type_for_map(btf, map_ident); @@ -280,6 +286,96 @@ out: return err; } +static bool btf_is_ptr_to_func_proto(const struct btf *btf, + const struct btf_type *v) +{ + return btf_is_ptr(v) && btf_is_func_proto(btf__type_by_id(btf, v->type)); +} + +static int codegen_subskel_datasecs(struct bpf_object *obj, const char *obj_name) +{ + struct btf *btf = bpf_object__btf(obj); + struct btf_dump *d; + struct bpf_map *map; + const struct btf_type *sec, *var; + const struct btf_var_secinfo *sec_var; + int i, err = 0, vlen; + char map_ident[256], sec_ident[256]; + bool strip_mods = false, needs_typeof = false; + const char *sec_name, *var_name; + __u32 var_type_id; + + d = btf_dump__new(btf, codegen_btf_dump_printf, NULL, NULL); + if (!d) + return -errno; + + bpf_object__for_each_map(map, obj) { + /* only generate definitions for memory-mapped internal maps */ + if (!is_internal_mmapable_map(map, map_ident, sizeof(map_ident))) + continue; + + sec = find_type_for_map(btf, map_ident); + if (!sec) + continue; + + sec_name = btf__name_by_offset(btf, sec->name_off); + if (!get_datasec_ident(sec_name, sec_ident, sizeof(sec_ident))) + continue; + + strip_mods = strcmp(sec_name, ".kconfig") != 0; + printf(" struct %s__%s {\n", obj_name, sec_ident); + + sec_var = btf_var_secinfos(sec); + vlen = btf_vlen(sec); + for (i = 0; i < vlen; i++, sec_var++) { + DECLARE_LIBBPF_OPTS(btf_dump_emit_type_decl_opts, opts, + .indent_level = 2, + .strip_mods = strip_mods, + /* we'll print the name separately */ + .field_name = "", + ); + + var = btf__type_by_id(btf, sec_var->type); + var_name = btf__name_by_offset(btf, var->name_off); + var_type_id = var->type; + + /* static variables are not exposed through BPF skeleton */ + if (btf_var(var)->linkage == BTF_VAR_STATIC) + continue; + + /* The datasec member has KIND_VAR but we want the + * underlying type of the variable (e.g. KIND_INT). + */ + var = skip_mods_and_typedefs(btf, var->type, NULL); + + printf("\t\t"); + /* Func and array members require special handling. + * Instead of producing `typename *var`, they produce + * `typeof(typename) *var`. This allows us to keep a + * similar syntax where the identifier is just prefixed + * by *, allowing us to ignore C declaration minutiae. + */ + needs_typeof = btf_is_array(var) || btf_is_ptr_to_func_proto(btf, var); + if (needs_typeof) + printf("typeof("); + + err = btf_dump__emit_type_decl(d, var_type_id, &opts); + if (err) + goto out; + + if (needs_typeof) + printf(")"); + + printf(" *%s;\n", var_name); + } + printf(" } %s;\n", sec_ident); + } + +out: + btf_dump__free(d); + return err; +} + static void codegen(const char *template, ...) { const char *src, *end; @@ -389,11 +485,7 @@ static void codegen_asserts(struct bpf_object *obj, const char *obj_name) ", obj_name); bpf_object__for_each_map(map, obj) { - if (!bpf_map__is_internal(map)) - continue; - if (!(bpf_map__map_flags(map) & BPF_F_MMAPABLE)) - continue; - if (!get_map_ident(map, map_ident, sizeof(map_ident))) + if (!is_internal_mmapable_map(map, map_ident, sizeof(map_ident))) continue; sec = find_type_for_map(btf, map_ident); @@ -608,11 +700,7 @@ static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h const void *mmap_data = NULL; size_t mmap_size = 0; - if (!get_map_ident(map, ident, sizeof(ident))) - continue; - - if (!bpf_map__is_internal(map) || - !(bpf_map__map_flags(map) & BPF_F_MMAPABLE)) + if (!is_internal_mmapable_map(map, ident, sizeof(ident))) continue; codegen("\ @@ -671,11 +759,7 @@ static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h bpf_object__for_each_map(map, obj) { const char *mmap_flags; - if (!get_map_ident(map, ident, sizeof(ident))) - continue; - - if (!bpf_map__is_internal(map) || - !(bpf_map__map_flags(map) & BPF_F_MMAPABLE)) + if (!is_internal_mmapable_map(map, ident, sizeof(ident))) continue; if (bpf_map__map_flags(map) & BPF_F_RDONLY_PROG) @@ -727,10 +811,95 @@ out: return err; } +static void +codegen_maps_skeleton(struct bpf_object *obj, size_t map_cnt, bool mmaped) +{ + struct bpf_map *map; + char ident[256]; + size_t i; + + if (!map_cnt) + return; + + codegen("\ + \n\ + \n\ + /* maps */ \n\ + s->map_cnt = %zu; \n\ + s->map_skel_sz = sizeof(*s->maps); \n\ + s->maps = (struct bpf_map_skeleton *)calloc(s->map_cnt, s->map_skel_sz);\n\ + if (!s->maps) \n\ + goto err; \n\ + ", + map_cnt + ); + i = 0; + bpf_object__for_each_map(map, obj) { + if (!get_map_ident(map, ident, sizeof(ident))) + continue; + + codegen("\ + \n\ + \n\ + s->maps[%zu].name = \"%s\"; \n\ + s->maps[%zu].map = &obj->maps.%s; \n\ + ", + i, bpf_map__name(map), i, ident); + /* memory-mapped internal maps */ + if (mmaped && is_internal_mmapable_map(map, ident, sizeof(ident))) { + printf("\ts->maps[%zu].mmaped = (void **)&obj->%s;\n", + i, ident); + } + i++; + } +} + +static void +codegen_progs_skeleton(struct bpf_object *obj, size_t prog_cnt, bool populate_links) +{ + struct bpf_program *prog; + int i; + + if (!prog_cnt) + return; + + codegen("\ + \n\ + \n\ + /* programs */ \n\ + s->prog_cnt = %zu; \n\ + s->prog_skel_sz = sizeof(*s->progs); \n\ + s->progs = (struct bpf_prog_skeleton *)calloc(s->prog_cnt, s->prog_skel_sz);\n\ + if (!s->progs) \n\ + goto err; \n\ + ", + prog_cnt + ); + i = 0; + bpf_object__for_each_program(prog, obj) { + codegen("\ + \n\ + \n\ + s->progs[%1$zu].name = \"%2$s\"; \n\ + s->progs[%1$zu].prog = &obj->progs.%2$s;\n\ + ", + i, bpf_program__name(prog)); + + if (populate_links) { + codegen("\ + \n\ + s->progs[%1$zu].link = &obj->links.%2$s;\n\ + ", + i, bpf_program__name(prog)); + } + i++; + } +} + static int do_skeleton(int argc, char **argv) { char header_guard[MAX_OBJ_NAME_LEN + sizeof("__SKEL_H__")]; - size_t i, map_cnt = 0, prog_cnt = 0, file_sz, mmap_sz; + size_t map_cnt = 0, prog_cnt = 0, file_sz, mmap_sz; DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts); char obj_name[MAX_OBJ_NAME_LEN] = "", *obj_data; struct bpf_object *obj = NULL; @@ -821,7 +990,7 @@ static int do_skeleton(int argc, char **argv) prog_cnt++; } - get_header_guard(header_guard, obj_name); + get_header_guard(header_guard, obj_name, "SKEL_H"); if (use_loader) { codegen("\ \n\ @@ -1024,66 +1193,10 @@ static int do_skeleton(int argc, char **argv) ", obj_name ); - if (map_cnt) { - codegen("\ - \n\ - \n\ - /* maps */ \n\ - s->map_cnt = %zu; \n\ - s->map_skel_sz = sizeof(*s->maps); \n\ - s->maps = (struct bpf_map_skeleton *)calloc(s->map_cnt, s->map_skel_sz);\n\ - if (!s->maps) \n\ - goto err; \n\ - ", - map_cnt - ); - i = 0; - bpf_object__for_each_map(map, obj) { - if (!get_map_ident(map, ident, sizeof(ident))) - continue; - codegen("\ - \n\ - \n\ - s->maps[%zu].name = \"%s\"; \n\ - s->maps[%zu].map = &obj->maps.%s; \n\ - ", - i, bpf_map__name(map), i, ident); - /* memory-mapped internal maps */ - if (bpf_map__is_internal(map) && - (bpf_map__map_flags(map) & BPF_F_MMAPABLE)) { - printf("\ts->maps[%zu].mmaped = (void **)&obj->%s;\n", - i, ident); - } - i++; - } - } - if (prog_cnt) { - codegen("\ - \n\ - \n\ - /* programs */ \n\ - s->prog_cnt = %zu; \n\ - s->prog_skel_sz = sizeof(*s->progs); \n\ - s->progs = (struct bpf_prog_skeleton *)calloc(s->prog_cnt, s->prog_skel_sz);\n\ - if (!s->progs) \n\ - goto err; \n\ - ", - prog_cnt - ); - i = 0; - bpf_object__for_each_program(prog, obj) { - codegen("\ - \n\ - \n\ - s->progs[%1$zu].name = \"%2$s\"; \n\ - s->progs[%1$zu].prog = &obj->progs.%2$s;\n\ - s->progs[%1$zu].link = &obj->links.%2$s;\n\ - ", - i, bpf_program__name(prog)); - i++; - } - } + codegen_maps_skeleton(obj, map_cnt, true /*mmaped*/); + codegen_progs_skeleton(obj, prog_cnt, true /*populate_links*/); + codegen("\ \n\ \n\ @@ -1141,6 +1254,311 @@ out: return err; } +/* Subskeletons are like skeletons, except they don't own the bpf_object, + * associated maps, links, etc. Instead, they know about the existence of + * variables, maps, programs and are able to find their locations + * _at runtime_ from an already loaded bpf_object. + * + * This allows for library-like BPF objects to have userspace counterparts + * with access to their own items without having to know anything about the + * final BPF object that the library was linked into. + */ +static int do_subskeleton(int argc, char **argv) +{ + char header_guard[MAX_OBJ_NAME_LEN + sizeof("__SUBSKEL_H__")]; + size_t i, len, file_sz, map_cnt = 0, prog_cnt = 0, mmap_sz, var_cnt = 0, var_idx = 0; + DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts); + char obj_name[MAX_OBJ_NAME_LEN] = "", *obj_data; + struct bpf_object *obj = NULL; + const char *file, *var_name; + char ident[256]; + int fd, err = -1, map_type_id; + const struct bpf_map *map; + struct bpf_program *prog; + struct btf *btf; + const struct btf_type *map_type, *var_type; + const struct btf_var_secinfo *var; + struct stat st; + + if (!REQ_ARGS(1)) { + usage(); + return -1; + } + file = GET_ARG(); + + while (argc) { + if (!REQ_ARGS(2)) + return -1; + + if (is_prefix(*argv, "name")) { + NEXT_ARG(); + + if (obj_name[0] != '\0') { + p_err("object name already specified"); + return -1; + } + + strncpy(obj_name, *argv, MAX_OBJ_NAME_LEN - 1); + obj_name[MAX_OBJ_NAME_LEN - 1] = '\0'; + } else { + p_err("unknown arg %s", *argv); + return -1; + } + + NEXT_ARG(); + } + + if (argc) { + p_err("extra unknown arguments"); + return -1; + } + + if (use_loader) { + p_err("cannot use loader for subskeletons"); + return -1; + } + + if (stat(file, &st)) { + p_err("failed to stat() %s: %s", file, strerror(errno)); + return -1; + } + file_sz = st.st_size; + mmap_sz = roundup(file_sz, sysconf(_SC_PAGE_SIZE)); + fd = open(file, O_RDONLY); + if (fd < 0) { + p_err("failed to open() %s: %s", file, strerror(errno)); + return -1; + } + obj_data = mmap(NULL, mmap_sz, PROT_READ, MAP_PRIVATE, fd, 0); + if (obj_data == MAP_FAILED) { + obj_data = NULL; + p_err("failed to mmap() %s: %s", file, strerror(errno)); + goto out; + } + if (obj_name[0] == '\0') + get_obj_name(obj_name, file); + + /* The empty object name allows us to use bpf_map__name and produce + * ELF section names out of it. (".data" instead of "obj.data") + */ + opts.object_name = ""; + obj = bpf_object__open_mem(obj_data, file_sz, &opts); + if (!obj) { + char err_buf[256]; + + libbpf_strerror(errno, err_buf, sizeof(err_buf)); + p_err("failed to open BPF object file: %s", err_buf); + obj = NULL; + goto out; + } + + btf = bpf_object__btf(obj); + if (!btf) { + err = -1; + p_err("need btf type information for %s", obj_name); + goto out; + } + + bpf_object__for_each_program(prog, obj) { + prog_cnt++; + } + + /* First, count how many variables we have to find. + * We need this in advance so the subskel can allocate the right + * amount of storage. + */ + bpf_object__for_each_map(map, obj) { + if (!get_map_ident(map, ident, sizeof(ident))) + continue; + + /* Also count all maps that have a name */ + map_cnt++; + + if (!is_internal_mmapable_map(map, ident, sizeof(ident))) + continue; + + map_type_id = bpf_map__btf_value_type_id(map); + if (map_type_id <= 0) { + err = map_type_id; + goto out; + } + map_type = btf__type_by_id(btf, map_type_id); + + var = btf_var_secinfos(map_type); + len = btf_vlen(map_type); + for (i = 0; i < len; i++, var++) { + var_type = btf__type_by_id(btf, var->type); + + if (btf_var(var_type)->linkage == BTF_VAR_STATIC) + continue; + + var_cnt++; + } + } + + get_header_guard(header_guard, obj_name, "SUBSKEL_H"); + codegen("\ + \n\ + /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ \n\ + \n\ + /* THIS FILE IS AUTOGENERATED! */ \n\ + #ifndef %2$s \n\ + #define %2$s \n\ + \n\ + #include \n\ + #include \n\ + #include \n\ + \n\ + struct %1$s { \n\ + struct bpf_object *obj; \n\ + struct bpf_object_subskeleton *subskel; \n\ + ", obj_name, header_guard); + + if (map_cnt) { + printf("\tstruct {\n"); + bpf_object__for_each_map(map, obj) { + if (!get_map_ident(map, ident, sizeof(ident))) + continue; + printf("\t\tstruct bpf_map *%s;\n", ident); + } + printf("\t} maps;\n"); + } + + if (prog_cnt) { + printf("\tstruct {\n"); + bpf_object__for_each_program(prog, obj) { + printf("\t\tstruct bpf_program *%s;\n", + bpf_program__name(prog)); + } + printf("\t} progs;\n"); + } + + err = codegen_subskel_datasecs(obj, obj_name); + if (err) + goto out; + + /* emit code that will allocate enough storage for all symbols */ + codegen("\ + \n\ + \n\ + #ifdef __cplusplus \n\ + static inline struct %1$s *open(const struct bpf_object *src);\n\ + static inline void destroy(struct %1$s *skel); \n\ + #endif /* __cplusplus */ \n\ + }; \n\ + \n\ + static inline void \n\ + %1$s__destroy(struct %1$s *skel) \n\ + { \n\ + if (!skel) \n\ + return; \n\ + if (skel->subskel) \n\ + bpf_object__destroy_subskeleton(skel->subskel);\n\ + free(skel); \n\ + } \n\ + \n\ + static inline struct %1$s * \n\ + %1$s__open(const struct bpf_object *src) \n\ + { \n\ + struct %1$s *obj; \n\ + struct bpf_object_subskeleton *s; \n\ + int err; \n\ + \n\ + obj = (struct %1$s *)calloc(1, sizeof(*obj)); \n\ + if (!obj) { \n\ + errno = ENOMEM; \n\ + goto err; \n\ + } \n\ + s = (struct bpf_object_subskeleton *)calloc(1, sizeof(*s));\n\ + if (!s) { \n\ + errno = ENOMEM; \n\ + goto err; \n\ + } \n\ + s->sz = sizeof(*s); \n\ + s->obj = src; \n\ + s->var_skel_sz = sizeof(*s->vars); \n\ + obj->subskel = s; \n\ + \n\ + /* vars */ \n\ + s->var_cnt = %2$d; \n\ + s->vars = (struct bpf_var_skeleton *)calloc(%2$d, sizeof(*s->vars));\n\ + if (!s->vars) { \n\ + errno = ENOMEM; \n\ + goto err; \n\ + } \n\ + ", + obj_name, var_cnt + ); + + /* walk through each symbol and emit the runtime representation */ + bpf_object__for_each_map(map, obj) { + if (!is_internal_mmapable_map(map, ident, sizeof(ident))) + continue; + + map_type_id = bpf_map__btf_value_type_id(map); + if (map_type_id <= 0) + /* skip over internal maps with no type*/ + continue; + + map_type = btf__type_by_id(btf, map_type_id); + var = btf_var_secinfos(map_type); + len = btf_vlen(map_type); + for (i = 0; i < len; i++, var++) { + var_type = btf__type_by_id(btf, var->type); + var_name = btf__name_by_offset(btf, var_type->name_off); + + if (btf_var(var_type)->linkage == BTF_VAR_STATIC) + continue; + + /* Note that we use the dot prefix in .data as the + * field access operator i.e. maps%s becomes maps.data + */ + codegen("\ + \n\ + \n\ + s->vars[%3$d].name = \"%1$s\"; \n\ + s->vars[%3$d].map = &obj->maps.%2$s; \n\ + s->vars[%3$d].addr = (void **) &obj->%2$s.%1$s;\n\ + ", var_name, ident, var_idx); + + var_idx++; + } + } + + codegen_maps_skeleton(obj, map_cnt, false /*mmaped*/); + codegen_progs_skeleton(obj, prog_cnt, false /*links*/); + + codegen("\ + \n\ + \n\ + err = bpf_object__open_subskeleton(s); \n\ + if (err) \n\ + goto err; \n\ + \n\ + return obj; \n\ + err: \n\ + %1$s__destroy(obj); \n\ + errno = -err; \n\ + return NULL; \n\ + } \n\ + \n\ + #ifdef __cplusplus \n\ + struct %1$s *%1$s::open(const struct bpf_object *src) { return %1$s__open(src); }\n\ + void %1$s::destroy(struct %1$s *skel) { %1$s__destroy(skel); }\n\ + #endif /* __cplusplus */ \n\ + \n\ + #endif /* %2$s */ \n\ + ", + obj_name, header_guard); + err = 0; +out: + bpf_object__close(obj); + if (obj_data) + munmap(obj_data, mmap_sz); + close(fd); + return err; +} + static int do_object(int argc, char **argv) { struct bpf_linker *linker; @@ -1192,6 +1610,7 @@ static int do_help(int argc, char **argv) fprintf(stderr, "Usage: %1$s %2$s object OUTPUT_FILE INPUT_FILE [INPUT_FILE...]\n" " %1$s %2$s skeleton FILE [name OBJECT_NAME]\n" + " %1$s %2$s subskeleton FILE [name OBJECT_NAME]\n" " %1$s %2$s min_core_btf INPUT OUTPUT OBJECT [OBJECT...]\n" " %1$s %2$s help\n" "\n" @@ -1788,6 +2207,7 @@ static int do_min_core_btf(int argc, char **argv) static const struct cmd cmds[] = { { "object", do_object }, { "skeleton", do_skeleton }, + { "subskeleton", do_subskeleton }, { "min_core_btf", do_min_core_btf}, { "help", do_help }, { 0 } -- cgit v1.2.3 From 08063b4bc1581bbdcae99da4a54f546a50045fc0 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Fri, 18 Mar 2022 08:01:06 -0700 Subject: bpftool: Add BPF_TRACE_KPROBE_MULTI to attach type names table BPF_TRACE_KPROBE_MULTI is a new attach type name, add it to bpftool's table. This fixes a currently failing CI bpftool check. Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20220318150106.2933343-1-andrii@kernel.org --- tools/bpf/bpftool/common.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/common.c b/tools/bpf/bpftool/common.c index 606743c6db41..0c1e06cf50b9 100644 --- a/tools/bpf/bpftool/common.c +++ b/tools/bpf/bpftool/common.c @@ -56,7 +56,6 @@ const char * const attach_type_name[__MAX_BPF_ATTACH_TYPE] = { [BPF_CGROUP_UDP6_RECVMSG] = "recvmsg6", [BPF_CGROUP_GETSOCKOPT] = "getsockopt", [BPF_CGROUP_SETSOCKOPT] = "setsockopt", - [BPF_SK_SKB_STREAM_PARSER] = "sk_skb_stream_parser", [BPF_SK_SKB_STREAM_VERDICT] = "sk_skb_stream_verdict", [BPF_SK_SKB_VERDICT] = "sk_skb_verdict", @@ -76,6 +75,7 @@ const char * const attach_type_name[__MAX_BPF_ATTACH_TYPE] = { [BPF_SK_REUSEPORT_SELECT] = "sk_skb_reuseport_select", [BPF_SK_REUSEPORT_SELECT_OR_MIGRATE] = "sk_skb_reuseport_select_or_migrate", [BPF_PERF_EVENT] = "perf_event", + [BPF_TRACE_KPROBE_MULTI] = "trace_kprobe_multi", }; void p_err(const char *fmt, ...) -- cgit v1.2.3 From 1824d8ea75f275a5e69e5f6bc0ffe122ea9b938c Mon Sep 17 00:00:00 2001 From: Yafang Shao Date: Sun, 20 Mar 2022 06:08:14 +0000 Subject: bpftool: Fix print error when show bpf map If there is no btf_id or frozen, it will not show the pids, but the pids don't depend on any one of them. Below is the result after this change: $ ./bpftool map show 2: lpm_trie flags 0x1 key 8B value 8B max_entries 1 memlock 4096B pids systemd(1) 3: lpm_trie flags 0x1 key 20B value 8B max_entries 1 memlock 4096B pids systemd(1) While before this change, the 'pids systemd(1)' can't be displayed. Fixes: 9330986c0300 ("bpf: Add bloom filter map implementation") Signed-off-by: Yafang Shao Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20220320060815.7716-1-laoar.shao@gmail.com --- tools/bpf/bpftool/map.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c index f91d9bf9054e..c26378f20831 100644 --- a/tools/bpf/bpftool/map.c +++ b/tools/bpf/bpftool/map.c @@ -620,17 +620,14 @@ static int show_map_close_plain(int fd, struct bpf_map_info *info) u32_as_hash_field(info->id)) printf("\n\tpinned %s", (char *)entry->value); } - printf("\n"); if (frozen_str) { frozen = atoi(frozen_str); free(frozen_str); } - if (!info->btf_id && !frozen) - return 0; - - printf("\t"); + if (info->btf_id || frozen) + printf("\n\t"); if (info->btf_id) printf("btf_id %d", info->btf_id); -- cgit v1.2.3 From f97b8b9bd630fb76c0e9e11cbf390e3d64a144d7 Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Sat, 19 Mar 2022 20:20:09 -0700 Subject: bpftool: Fix a bug in subskeleton code generation Compiled with clang by adding LLVM=1 both kernel and selftests/bpf build, I hit the following compilation error: In file included from /.../tools/testing/selftests/bpf/prog_tests/subskeleton.c:6: ./test_subskeleton_lib.subskel.h:168:6: error: variable 'err' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized] if (!s->progs) ^~~~~~~~~ ./test_subskeleton_lib.subskel.h:181:11: note: uninitialized use occurs here errno = -err; ^~~ ./test_subskeleton_lib.subskel.h:168:2: note: remove the 'if' if its condition is always false if (!s->progs) ^~~~~~~~~~~~~~ The compilation error is triggered by the following code ... int err; obj = (struct test_subskeleton_lib *)calloc(1, sizeof(*obj)); if (!obj) { errno = ENOMEM; goto err; } ... err: test_subskeleton_lib__destroy(obj); errno = -err; ... in test_subskeleton_lib__open(). The 'err' is not initialized, yet it is used in 'errno = -err' later. The fix is to remove 'errno = -err' since errno has been set properly in all incoming branches. Fixes: 00389c58ffe9 ("bpftool: Add support for subskeletons") Signed-off-by: Yonghong Song Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20220320032009.3106133-1-yhs@fb.com --- tools/bpf/bpftool/gen.c | 1 - 1 file changed, 1 deletion(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index 96bd2b33ccf6..7ba7ff55d2ea 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -1538,7 +1538,6 @@ static int do_subskeleton(int argc, char **argv) return obj; \n\ err: \n\ %1$s__destroy(obj); \n\ - errno = -err; \n\ return NULL; \n\ } \n\ \n\ -- cgit v1.2.3