From 32e3e58e4c5910bb0d6024d151c2f559bb7e973c Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Mon, 7 Oct 2019 15:56:04 -0700 Subject: bpftool: Fix bpftool build by switching to bpf_object__open_file() As part of libbpf in 5e61f2707029 ("libbpf: stop enforcing kern_version, populate it for users") non-LIBBPF_API __bpf_object__open_xattr() API was removed from libbpf.h header. This broke bpftool, which relied on that function. This patch fixes the build by switching to newly added bpf_object__open_file() which provides the same capabilities, but is official and future-proof API. v1->v2: - fix prog_type shadowing (Stanislav). Fixes: 5e61f2707029 ("libbpf: stop enforcing kern_version, populate it for users") Reported-by: Stanislav Fomichev Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Reviewed-by: Stanislav Fomichev Link: https://lore.kernel.org/bpf/20191007225604.2006146-1-andriin@fb.com --- tools/bpf/bpftool/prog.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) (limited to 'tools/bpf/bpftool/prog.c') diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 43fdbbfe41bb..27da96a797ab 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -1092,9 +1092,7 @@ free_data_in: static int load_with_options(int argc, char **argv, bool first_prog_only) { struct bpf_object_load_attr load_attr = { 0 }; - struct bpf_object_open_attr open_attr = { - .prog_type = BPF_PROG_TYPE_UNSPEC, - }; + enum bpf_prog_type common_prog_type = BPF_PROG_TYPE_UNSPEC; enum bpf_attach_type expected_attach_type; struct map_replace *map_replace = NULL; struct bpf_program *prog = NULL, *pos; @@ -1105,11 +1103,16 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) const char *pinfile; unsigned int i, j; __u32 ifindex = 0; + const char *file; int idx, err; + LIBBPF_OPTS(bpf_object_open_opts, open_opts, + .relaxed_maps = relaxed_maps, + ); + if (!REQ_ARGS(2)) return -1; - open_attr.file = GET_ARG(); + file = GET_ARG(); pinfile = GET_ARG(); while (argc) { @@ -1118,7 +1121,7 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) NEXT_ARG(); - if (open_attr.prog_type != BPF_PROG_TYPE_UNSPEC) { + if (common_prog_type != BPF_PROG_TYPE_UNSPEC) { p_err("program type already specified"); goto err_free_reuse_maps; } @@ -1135,8 +1138,7 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) strcat(type, *argv); strcat(type, "/"); - err = libbpf_prog_type_by_name(type, - &open_attr.prog_type, + err = libbpf_prog_type_by_name(type, &common_prog_type, &expected_attach_type); free(type); if (err < 0) @@ -1224,16 +1226,16 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) set_max_rlimit(); - obj = __bpf_object__open_xattr(&open_attr, bpf_flags); + obj = bpf_object__open_file(file, &open_opts); if (IS_ERR_OR_NULL(obj)) { p_err("failed to open object file"); goto err_free_reuse_maps; } bpf_object__for_each_program(pos, obj) { - enum bpf_prog_type prog_type = open_attr.prog_type; + enum bpf_prog_type prog_type = common_prog_type; - if (open_attr.prog_type == BPF_PROG_TYPE_UNSPEC) { + if (prog_type == BPF_PROG_TYPE_UNSPEC) { const char *sec_name = bpf_program__title(pos, false); err = libbpf_prog_type_by_name(sec_name, &prog_type, -- cgit v1.2.3 From e00aca65e646da08f8dce31c9b89f11dab76198c Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Tue, 22 Oct 2019 10:21:00 -0700 Subject: libbpf: Make DECLARE_LIBBPF_OPTS macro strictly a variable declaration MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit LIBBPF_OPTS is implemented as a mix of field declaration and memset + assignment. This makes it neither variable declaration nor purely statements, which is a problem, because you can't mix it with either other variable declarations nor other function statements, because C90 compiler mode emits warning on mixing all that together. This patch changes LIBBPF_OPTS into a strictly declaration of variable and solves this problem, as can be seen in case of bpftool, which previously would emit compiler warning, if done this way (LIBBPF_OPTS as part of function variables declaration block). This patch also renames LIBBPF_OPTS into DECLARE_LIBBPF_OPTS to follow kernel convention for similar macros more closely. v1->v2: - rename LIBBPF_OPTS into DECLARE_LIBBPF_OPTS (Jakub Sitnicki). Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Acked-by: Toke Høiland-Jørgensen Link: https://lore.kernel.org/bpf/20191022172100.3281465-1-andriin@fb.com --- tools/bpf/bpftool/prog.c | 8 ++++---- tools/lib/bpf/libbpf.c | 4 ++-- tools/lib/bpf/libbpf.h | 19 ++++++++++++------- tools/testing/selftests/bpf/prog_tests/attach_probe.c | 2 +- tools/testing/selftests/bpf/prog_tests/core_reloc.c | 2 +- .../selftests/bpf/prog_tests/reference_tracking.c | 2 +- 6 files changed, 21 insertions(+), 16 deletions(-) (limited to 'tools/bpf/bpftool/prog.c') diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 27da96a797ab..4535c863d2cd 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -1091,8 +1091,11 @@ free_data_in: static int load_with_options(int argc, char **argv, bool first_prog_only) { - struct bpf_object_load_attr load_attr = { 0 }; enum bpf_prog_type common_prog_type = BPF_PROG_TYPE_UNSPEC; + DECLARE_LIBBPF_OPTS(bpf_object_open_opts, open_opts, + .relaxed_maps = relaxed_maps, + ); + struct bpf_object_load_attr load_attr = { 0 }; enum bpf_attach_type expected_attach_type; struct map_replace *map_replace = NULL; struct bpf_program *prog = NULL, *pos; @@ -1106,9 +1109,6 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) const char *file; int idx, err; - LIBBPF_OPTS(bpf_object_open_opts, open_opts, - .relaxed_maps = relaxed_maps, - ); if (!REQ_ARGS(2)) return -1; diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 803219d6898c..8b4d765c422b 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -3678,7 +3678,7 @@ out: static struct bpf_object * __bpf_object__open_xattr(struct bpf_object_open_attr *attr, int flags) { - LIBBPF_OPTS(bpf_object_open_opts, opts, + DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts, .relaxed_maps = flags & MAPS_RELAX_COMPAT, ); @@ -3730,7 +3730,7 @@ struct bpf_object * bpf_object__open_buffer(const void *obj_buf, size_t obj_buf_sz, const char *name) { - LIBBPF_OPTS(bpf_object_open_opts, opts, + DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts, .object_name = name, /* wrong default, but backwards-compatible */ .relaxed_maps = true, diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 0fdf086beba7..c63e2ff84abc 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -75,14 +75,19 @@ struct bpf_object_open_attr { * have all the padding bytes initialized to zero. It's not guaranteed though, * when copying literal, that compiler won't copy garbage in literal's padding * bytes, but that's the best way I've found and it seems to work in practice. + * + * Macro declares opts struct of given type and name, zero-initializes, + * including any extra padding, it with memset() and then assigns initial + * values provided by users in struct initializer-syntax as varargs. */ -#define LIBBPF_OPTS(TYPE, NAME, ...) \ - struct TYPE NAME; \ - memset(&NAME, 0, sizeof(struct TYPE)); \ - NAME = (struct TYPE) { \ - .sz = sizeof(struct TYPE), \ - __VA_ARGS__ \ - } +#define DECLARE_LIBBPF_OPTS(TYPE, NAME, ...) \ + struct TYPE NAME = ({ \ + memset(&NAME, 0, sizeof(struct TYPE)); \ + (struct TYPE) { \ + .sz = sizeof(struct TYPE), \ + __VA_ARGS__ \ + }; \ + }) struct bpf_object_open_opts { /* size of this struct, for forward/backward compatiblity */ diff --git a/tools/testing/selftests/bpf/prog_tests/attach_probe.c b/tools/testing/selftests/bpf/prog_tests/attach_probe.c index 0ee1ce100a4a..a83111a32d4a 100644 --- a/tools/testing/selftests/bpf/prog_tests/attach_probe.c +++ b/tools/testing/selftests/bpf/prog_tests/attach_probe.c @@ -50,7 +50,7 @@ void test_attach_probe(void) const int kprobe_idx = 0, kretprobe_idx = 1; const int uprobe_idx = 2, uretprobe_idx = 3; const char *obj_name = "attach_probe"; - LIBBPF_OPTS(bpf_object_open_opts, open_opts, + DECLARE_LIBBPF_OPTS(bpf_object_open_opts, open_opts, .object_name = obj_name, .relaxed_maps = true, ); diff --git a/tools/testing/selftests/bpf/prog_tests/core_reloc.c b/tools/testing/selftests/bpf/prog_tests/core_reloc.c index 523dca82dc82..09dfa75fe948 100644 --- a/tools/testing/selftests/bpf/prog_tests/core_reloc.c +++ b/tools/testing/selftests/bpf/prog_tests/core_reloc.c @@ -377,7 +377,7 @@ void test_core_reloc(void) if (!test__start_subtest(test_case->case_name)) continue; - LIBBPF_OPTS(bpf_object_open_opts, opts, + DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts, .relaxed_core_relocs = test_case->relaxed_core_relocs, ); diff --git a/tools/testing/selftests/bpf/prog_tests/reference_tracking.c b/tools/testing/selftests/bpf/prog_tests/reference_tracking.c index 4493ba277bd7..fc0d7f4f02cf 100644 --- a/tools/testing/selftests/bpf/prog_tests/reference_tracking.c +++ b/tools/testing/selftests/bpf/prog_tests/reference_tracking.c @@ -5,7 +5,7 @@ void test_reference_tracking(void) { const char *file = "test_sk_lookup_kern.o"; const char *obj_name = "ref_track"; - LIBBPF_OPTS(bpf_object_open_opts, open_opts, + DECLARE_LIBBPF_OPTS(bpf_object_open_opts, open_opts, .object_name = obj_name, .relaxed_maps = true, ); -- cgit v1.2.3