From cd31039a7347610863aa8b77a9162048999723d0 Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Thu, 23 Jul 2020 11:41:17 -0700 Subject: tools/libbpf: Add support for bpf map element iterator Add map_fd to bpf_iter_attach_opts and flags to bpf_link_create_opts. Later on, bpftool or selftest will be able to create a bpf map element iterator by passing map_fd to the kernel during link creation time. Signed-off-by: Yonghong Song Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200723184117.590673-1-yhs@fb.com --- tools/lib/bpf/bpf.c | 1 + tools/lib/bpf/bpf.h | 3 ++- tools/lib/bpf/libbpf.c | 10 +++++++++- tools/lib/bpf/libbpf.h | 3 ++- 4 files changed, 14 insertions(+), 3 deletions(-) (limited to 'tools/lib') diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index a7329b671c41..e1bdf214f75f 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -598,6 +598,7 @@ int bpf_link_create(int prog_fd, int target_fd, attr.link_create.prog_fd = prog_fd; attr.link_create.target_fd = target_fd; attr.link_create.attach_type = attach_type; + attr.link_create.flags = OPTS_GET(opts, flags, 0); return sys_bpf(BPF_LINK_CREATE, &attr, sizeof(attr)); } diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h index dbef24ebcfcb..6d367e01d05e 100644 --- a/tools/lib/bpf/bpf.h +++ b/tools/lib/bpf/bpf.h @@ -170,8 +170,9 @@ LIBBPF_API int bpf_prog_detach2(int prog_fd, int attachable_fd, struct bpf_link_create_opts { size_t sz; /* size of this struct for forward/backward compatibility */ + __u32 flags; }; -#define bpf_link_create_opts__last_field sz +#define bpf_link_create_opts__last_field flags LIBBPF_API int bpf_link_create(int prog_fd, int target_fd, enum bpf_attach_type attach_type, diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 846164c79df1..a05aa7e2bab6 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -8282,13 +8282,20 @@ struct bpf_link * bpf_program__attach_iter(struct bpf_program *prog, const struct bpf_iter_attach_opts *opts) { + DECLARE_LIBBPF_OPTS(bpf_link_create_opts, link_create_opts); char errmsg[STRERR_BUFSIZE]; struct bpf_link *link; int prog_fd, link_fd; + __u32 target_fd = 0; if (!OPTS_VALID(opts, bpf_iter_attach_opts)) return ERR_PTR(-EINVAL); + if (OPTS_HAS(opts, map_fd)) { + target_fd = opts->map_fd; + link_create_opts.flags = BPF_ITER_LINK_MAP_FD; + } + prog_fd = bpf_program__fd(prog); if (prog_fd < 0) { pr_warn("program '%s': can't attach before loaded\n", @@ -8301,7 +8308,8 @@ bpf_program__attach_iter(struct bpf_program *prog, return ERR_PTR(-ENOMEM); link->detach = &bpf_link__detach_fd; - link_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_ITER, NULL); + link_fd = bpf_link_create(prog_fd, target_fd, BPF_TRACE_ITER, + &link_create_opts); if (link_fd < 0) { link_fd = -errno; free(link); diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index c2272132e929..c6813791fa7e 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -264,8 +264,9 @@ LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(struct bpf_map *map); struct bpf_iter_attach_opts { size_t sz; /* size of this struct for forward/backward compatibility */ + __u32 map_fd; }; -#define bpf_iter_attach_opts__last_field sz +#define bpf_iter_attach_opts__last_field map_fd LIBBPF_API struct bpf_link * bpf_program__attach_iter(struct bpf_program *prog, -- cgit v1.2.3-58-ga151 From d4b4dd6ce7709c2d2fe56dcfc15074ee18505bcb Mon Sep 17 00:00:00 2001 From: Song Liu Date: Thu, 23 Jul 2020 11:06:46 -0700 Subject: libbpf: Print hint when PERF_EVENT_IOC_SET_BPF returns -EPROTO The kernel prevents potential unwinder warnings and crashes by blocking BPF program with bpf_get_[stack|stackid] on perf_event without PERF_SAMPLE_CALLCHAIN, or with exclude_callchain_[kernel|user]. Print a hint message in libbpf to help the user debug such issues. Signed-off-by: Song Liu Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200723180648.1429892-4-songliubraving@fb.com --- tools/lib/bpf/libbpf.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'tools/lib') diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index a05aa7e2bab6..e51479d60285 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -7833,6 +7833,9 @@ struct bpf_link *bpf_program__attach_perf_event(struct bpf_program *prog, pr_warn("program '%s': failed to attach to pfd %d: %s\n", bpf_program__title(prog, false), pfd, libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + if (err == -EPROTO) + pr_warn("program '%s': try add PERF_SAMPLE_CALLCHAIN to or remove exclude_callchain_[kernel|user] from pfd %d\n", + bpf_program__title(prog, false), pfd); return ERR_PTR(err); } if (ioctl(pfd, PERF_EVENT_IOC_ENABLE, 0) < 0) { -- cgit v1.2.3-58-ga151 From dc8698cac7aada9b61a612cb819341d84591163e Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Tue, 21 Jul 2020 23:46:00 -0700 Subject: libbpf: Add support for BPF XDP link Sync UAPI header and add support for using bpf_link-based XDP attachment. Make xdp/ prog type set expected attach type. Kernel didn't enforce attach_type for XDP programs before, so there is no backwards compatiblity issues there. Also fix section_names selftest to recognize that xdp prog types now have expected attach type. Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200722064603.3350758-8-andriin@fb.com --- tools/include/uapi/linux/bpf.h | 10 +++++++++- tools/lib/bpf/libbpf.c | 9 ++++++++- tools/lib/bpf/libbpf.h | 2 ++ tools/lib/bpf/libbpf.map | 1 + tools/testing/selftests/bpf/prog_tests/section_names.c | 2 +- 5 files changed, 21 insertions(+), 3 deletions(-) (limited to 'tools/lib') diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 828c2f6438f2..e1ba4ae6a916 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -230,6 +230,7 @@ enum bpf_attach_type { BPF_CGROUP_INET_SOCK_RELEASE, BPF_XDP_CPUMAP, BPF_SK_LOOKUP, + BPF_XDP, __MAX_BPF_ATTACH_TYPE }; @@ -242,6 +243,7 @@ enum bpf_link_type { BPF_LINK_TYPE_CGROUP = 3, BPF_LINK_TYPE_ITER = 4, BPF_LINK_TYPE_NETNS = 5, + BPF_LINK_TYPE_XDP = 6, MAX_BPF_LINK_TYPE, }; @@ -614,7 +616,10 @@ union bpf_attr { struct { /* struct used by BPF_LINK_CREATE command */ __u32 prog_fd; /* eBPF program to attach */ - __u32 target_fd; /* object to attach to */ + union { + __u32 target_fd; /* object to attach to */ + __u32 target_ifindex; /* target ifindex */ + }; __u32 attach_type; /* attach type */ __u32 flags; /* extra flags */ } link_create; @@ -4064,6 +4069,9 @@ struct bpf_link_info { __u32 netns_ino; __u32 attach_type; } netns; + struct { + __u32 ifindex; + } xdp; }; } __attribute__((aligned(8))); diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index e51479d60285..54830d603fee 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -6915,7 +6915,8 @@ static const struct bpf_sec_def section_defs[] = { BPF_XDP_DEVMAP), BPF_EAPROG_SEC("xdp_cpumap/", BPF_PROG_TYPE_XDP, BPF_XDP_CPUMAP), - BPF_PROG_SEC("xdp", BPF_PROG_TYPE_XDP), + BPF_EAPROG_SEC("xdp", BPF_PROG_TYPE_XDP, + BPF_XDP), BPF_PROG_SEC("perf_event", BPF_PROG_TYPE_PERF_EVENT), BPF_PROG_SEC("lwt_in", BPF_PROG_TYPE_LWT_IN), BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT), @@ -8281,6 +8282,12 @@ bpf_program__attach_netns(struct bpf_program *prog, int netns_fd) return bpf_program__attach_fd(prog, netns_fd, "netns"); } +struct bpf_link *bpf_program__attach_xdp(struct bpf_program *prog, int ifindex) +{ + /* target_fd/target_ifindex use the same field in LINK_CREATE */ + return bpf_program__attach_fd(prog, ifindex, "xdp"); +} + struct bpf_link * bpf_program__attach_iter(struct bpf_program *prog, const struct bpf_iter_attach_opts *opts) diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index c6813791fa7e..9924385462ab 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -257,6 +257,8 @@ LIBBPF_API struct bpf_link * bpf_program__attach_cgroup(struct bpf_program *prog, int cgroup_fd); LIBBPF_API struct bpf_link * bpf_program__attach_netns(struct bpf_program *prog, int netns_fd); +LIBBPF_API struct bpf_link * +bpf_program__attach_xdp(struct bpf_program *prog, int ifindex); struct bpf_map; diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index 6f0856abe299..ca49a6a7e5b2 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -286,6 +286,7 @@ LIBBPF_0.1.0 { bpf_map__set_value_size; bpf_map__type; bpf_map__value_size; + bpf_program__attach_xdp; bpf_program__autoload; bpf_program__is_sk_lookup; bpf_program__set_autoload; diff --git a/tools/testing/selftests/bpf/prog_tests/section_names.c b/tools/testing/selftests/bpf/prog_tests/section_names.c index 713167449c98..8b571890c57e 100644 --- a/tools/testing/selftests/bpf/prog_tests/section_names.c +++ b/tools/testing/selftests/bpf/prog_tests/section_names.c @@ -35,7 +35,7 @@ static struct sec_name_test tests[] = { {-EINVAL, 0}, }, {"raw_tp/", {0, BPF_PROG_TYPE_RAW_TRACEPOINT, 0}, {-EINVAL, 0} }, - {"xdp", {0, BPF_PROG_TYPE_XDP, 0}, {-EINVAL, 0} }, + {"xdp", {0, BPF_PROG_TYPE_XDP, BPF_XDP}, {0, BPF_XDP} }, {"perf_event", {0, BPF_PROG_TYPE_PERF_EVENT, 0}, {-EINVAL, 0} }, {"lwt_in", {0, BPF_PROG_TYPE_LWT_IN, 0}, {-EINVAL, 0} }, {"lwt_out", {0, BPF_PROG_TYPE_LWT_OUT, 0}, {-EINVAL, 0} }, -- cgit v1.2.3-58-ga151 From 50450fc716c1a570ee8d8bfe198ef5d3cfca36e4 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Wed, 29 Jul 2020 16:21:48 -0700 Subject: libbpf: Make destructors more robust by handling ERR_PTR(err) cases Most of libbpf "constructors" on failure return ERR_PTR(err) result encoded as a pointer. It's a common mistake to eventually pass such malformed pointers into xxx__destroy()/xxx__free() "destructors". So instead of fixing up clean up code in selftests and user programs, handle such error pointers in destructors themselves. This works beautifully for NULL pointers passed to destructors, so might as well just work for error pointers. Suggested-by: Song Liu Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20200729232148.896125-1-andriin@fb.com --- tools/lib/bpf/btf.c | 4 ++-- tools/lib/bpf/btf_dump.c | 2 +- tools/lib/bpf/libbpf.c | 9 ++++----- 3 files changed, 7 insertions(+), 8 deletions(-) (limited to 'tools/lib') diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c index c9e760e120dc..ded5b29965f9 100644 --- a/tools/lib/bpf/btf.c +++ b/tools/lib/bpf/btf.c @@ -386,7 +386,7 @@ __s32 btf__find_by_name_kind(const struct btf *btf, const char *type_name, void btf__free(struct btf *btf) { - if (!btf) + if (IS_ERR_OR_NULL(btf)) return; if (btf->fd >= 0) @@ -1025,7 +1025,7 @@ static int btf_ext_parse_hdr(__u8 *data, __u32 data_size) void btf_ext__free(struct btf_ext *btf_ext) { - if (!btf_ext) + if (IS_ERR_OR_NULL(btf_ext)) return; free(btf_ext->data); free(btf_ext); diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c index e1c344504cae..cf711168d34a 100644 --- a/tools/lib/bpf/btf_dump.c +++ b/tools/lib/bpf/btf_dump.c @@ -183,7 +183,7 @@ void btf_dump__free(struct btf_dump *d) { int i, cnt; - if (!d) + if (IS_ERR_OR_NULL(d)) return; free(d->type_states); diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 54830d603fee..b9f11f854985 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -6504,7 +6504,7 @@ void bpf_object__close(struct bpf_object *obj) { size_t i; - if (!obj) + if (IS_ERR_OR_NULL(obj)) return; if (obj->clear_priv) @@ -7690,7 +7690,7 @@ int bpf_link__destroy(struct bpf_link *link) { int err = 0; - if (!link) + if (IS_ERR_OR_NULL(link)) return 0; if (!link->disconnected && link->detach) @@ -8502,7 +8502,7 @@ void perf_buffer__free(struct perf_buffer *pb) { int i; - if (!pb) + if (IS_ERR_OR_NULL(pb)) return; if (pb->cpu_bufs) { for (i = 0; i < pb->cpu_cnt; i++) { @@ -9379,8 +9379,7 @@ void bpf_object__detach_skeleton(struct bpf_object_skeleton *s) for (i = 0; i < s->prog_cnt; i++) { struct bpf_link **link = s->progs[i].link; - if (!IS_ERR_OR_NULL(*link)) - bpf_link__destroy(*link); + bpf_link__destroy(*link); *link = NULL; } } -- cgit v1.2.3-58-ga151 From 1acf8f90ea7ee59006d0474275922145ac291331 Mon Sep 17 00:00:00 2001 From: Jerry Crunchtime Date: Fri, 31 Jul 2020 17:08:01 +0200 Subject: libbpf: Fix register in PT_REGS MIPS macros The o32, n32 and n64 calling conventions require the return value to be stored in $v0 which maps to $2 register, i.e., the register 2. Fixes: c1932cd ("bpf: Add MIPS support to samples/bpf.") Signed-off-by: Jerry Crunchtime Signed-off-by: Daniel Borkmann Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/43707d31-0210-e8f0-9226-1af140907641@web.de --- tools/lib/bpf/bpf_tracing.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'tools/lib') diff --git a/tools/lib/bpf/bpf_tracing.h b/tools/lib/bpf/bpf_tracing.h index 58eceb884df3..eebf020cbe3e 100644 --- a/tools/lib/bpf/bpf_tracing.h +++ b/tools/lib/bpf/bpf_tracing.h @@ -215,7 +215,7 @@ struct pt_regs; #define PT_REGS_PARM5(x) ((x)->regs[8]) #define PT_REGS_RET(x) ((x)->regs[31]) #define PT_REGS_FP(x) ((x)->regs[30]) /* Works only with CONFIG_FRAME_POINTER */ -#define PT_REGS_RC(x) ((x)->regs[1]) +#define PT_REGS_RC(x) ((x)->regs[2]) #define PT_REGS_SP(x) ((x)->regs[29]) #define PT_REGS_IP(x) ((x)->cp0_epc) @@ -226,7 +226,7 @@ struct pt_regs; #define PT_REGS_PARM5_CORE(x) BPF_CORE_READ((x), regs[8]) #define PT_REGS_RET_CORE(x) BPF_CORE_READ((x), regs[31]) #define PT_REGS_FP_CORE(x) BPF_CORE_READ((x), regs[30]) -#define PT_REGS_RC_CORE(x) BPF_CORE_READ((x), regs[1]) +#define PT_REGS_RC_CORE(x) BPF_CORE_READ((x), regs[2]) #define PT_REGS_SP_CORE(x) BPF_CORE_READ((x), regs[29]) #define PT_REGS_IP_CORE(x) BPF_CORE_READ((x), cp0_epc) -- cgit v1.2.3-58-ga151 From 2e49527e52486dac910460b1b3f6fce6e21c6b48 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Fri, 31 Jul 2020 11:28:27 -0700 Subject: libbpf: Add bpf_link detach APIs Add low-level bpf_link_detach() API. Also add higher-level bpf_link__detach() one. Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Acked-by: Song Liu Acked-by: John Fastabend Link: https://lore.kernel.org/bpf/20200731182830.286260-3-andriin@fb.com --- tools/include/uapi/linux/bpf.h | 5 +++++ tools/lib/bpf/bpf.c | 10 ++++++++++ tools/lib/bpf/bpf.h | 2 ++ tools/lib/bpf/libbpf.c | 5 +++++ tools/lib/bpf/libbpf.h | 1 + tools/lib/bpf/libbpf.map | 2 ++ 6 files changed, 25 insertions(+) (limited to 'tools/lib') diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index eb5e0c38eb2c..b134e679e9db 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -117,6 +117,7 @@ enum bpf_cmd { BPF_LINK_GET_NEXT_ID, BPF_ENABLE_STATS, BPF_ITER_CREATE, + BPF_LINK_DETACH, }; enum bpf_map_type { @@ -634,6 +635,10 @@ union bpf_attr { __u32 old_prog_fd; } link_update; + struct { + __u32 link_fd; + } link_detach; + struct { /* struct used by BPF_ENABLE_STATS command */ __u32 type; } enable_stats; diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index e1bdf214f75f..eab14c97c15d 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -603,6 +603,16 @@ int bpf_link_create(int prog_fd, int target_fd, return sys_bpf(BPF_LINK_CREATE, &attr, sizeof(attr)); } +int bpf_link_detach(int link_fd) +{ + union bpf_attr attr; + + memset(&attr, 0, sizeof(attr)); + attr.link_detach.link_fd = link_fd; + + return sys_bpf(BPF_LINK_DETACH, &attr, sizeof(attr)); +} + int bpf_link_update(int link_fd, int new_prog_fd, const struct bpf_link_update_opts *opts) { diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h index 6d367e01d05e..28855fd5b5f4 100644 --- a/tools/lib/bpf/bpf.h +++ b/tools/lib/bpf/bpf.h @@ -178,6 +178,8 @@ LIBBPF_API int bpf_link_create(int prog_fd, int target_fd, enum bpf_attach_type attach_type, const struct bpf_link_create_opts *opts); +LIBBPF_API int bpf_link_detach(int link_fd); + struct bpf_link_update_opts { size_t sz; /* size of this struct for forward/backward compatibility */ __u32 flags; /* extra flags */ diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index b9f11f854985..7be04e45d29c 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -7748,6 +7748,11 @@ struct bpf_link *bpf_link__open(const char *path) return link; } +int bpf_link__detach(struct bpf_link *link) +{ + return bpf_link_detach(link->fd) ? -errno : 0; +} + int bpf_link__pin(struct bpf_link *link, const char *path) { int err; diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 9924385462ab..3ed1399bfbbc 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -229,6 +229,7 @@ LIBBPF_API int bpf_link__unpin(struct bpf_link *link); LIBBPF_API int bpf_link__update_program(struct bpf_link *link, struct bpf_program *prog); LIBBPF_API void bpf_link__disconnect(struct bpf_link *link); +LIBBPF_API int bpf_link__detach(struct bpf_link *link); LIBBPF_API int bpf_link__destroy(struct bpf_link *link); LIBBPF_API struct bpf_link * diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index ca49a6a7e5b2..099863411f7d 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -273,6 +273,8 @@ LIBBPF_0.0.9 { LIBBPF_0.1.0 { global: + bpf_link__detach; + bpf_link_detach; bpf_map__ifindex; bpf_map__key_size; bpf_map__map_flags; -- cgit v1.2.3-58-ga151 From 94a1fedd63edb672933bef44ca9213937e377c05 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Sat, 1 Aug 2020 18:32:17 -0700 Subject: libbpf: Add btf__parse_raw() and generic btf__parse() APIs Add public APIs to parse BTF from raw data file (e.g., /sys/kernel/btf/vmlinux), as well as generic btf__parse(), which will try to determine correct format, currently either raw or ELF. Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20200802013219.864880-2-andriin@fb.com --- tools/lib/bpf/btf.c | 114 ++++++++++++++++++++++++++++++++--------------- tools/lib/bpf/btf.h | 5 ++- tools/lib/bpf/libbpf.map | 2 + 3 files changed, 83 insertions(+), 38 deletions(-) (limited to 'tools/lib') diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c index ded5b29965f9..856b09a04563 100644 --- a/tools/lib/bpf/btf.c +++ b/tools/lib/bpf/btf.c @@ -562,6 +562,83 @@ done: return btf; } +struct btf *btf__parse_raw(const char *path) +{ + void *data = NULL; + struct btf *btf; + FILE *f = NULL; + __u16 magic; + int err = 0; + long sz; + + f = fopen(path, "rb"); + if (!f) { + err = -errno; + goto err_out; + } + + /* check BTF magic */ + if (fread(&magic, 1, sizeof(magic), f) < sizeof(magic)) { + err = -EIO; + goto err_out; + } + if (magic != BTF_MAGIC) { + /* definitely not a raw BTF */ + err = -EPROTO; + goto err_out; + } + + /* get file size */ + if (fseek(f, 0, SEEK_END)) { + err = -errno; + goto err_out; + } + sz = ftell(f); + if (sz < 0) { + err = -errno; + goto err_out; + } + /* rewind to the start */ + if (fseek(f, 0, SEEK_SET)) { + err = -errno; + goto err_out; + } + + /* pre-alloc memory and read all of BTF data */ + data = malloc(sz); + if (!data) { + err = -ENOMEM; + goto err_out; + } + if (fread(data, 1, sz, f) < sz) { + err = -EIO; + goto err_out; + } + + /* finally parse BTF data */ + btf = btf__new(data, sz); + +err_out: + free(data); + if (f) + fclose(f); + return err ? ERR_PTR(err) : btf; +} + +struct btf *btf__parse(const char *path, struct btf_ext **btf_ext) +{ + struct btf *btf; + + if (btf_ext) + *btf_ext = NULL; + + btf = btf__parse_raw(path); + if (!IS_ERR(btf) || PTR_ERR(btf) != -EPROTO) + return btf; + + return btf__parse_elf(path, btf_ext); +} + static int compare_vsi_off(const void *_a, const void *_b) { const struct btf_var_secinfo *a = _a; @@ -2951,41 +3028,6 @@ static int btf_dedup_remap_types(struct btf_dedup *d) return 0; } -static struct btf *btf_load_raw(const char *path) -{ - struct btf *btf; - size_t read_cnt; - struct stat st; - void *data; - FILE *f; - - if (stat(path, &st)) - return ERR_PTR(-errno); - - data = malloc(st.st_size); - if (!data) - return ERR_PTR(-ENOMEM); - - f = fopen(path, "rb"); - if (!f) { - btf = ERR_PTR(-errno); - goto cleanup; - } - - read_cnt = fread(data, 1, st.st_size, f); - fclose(f); - if (read_cnt < st.st_size) { - btf = ERR_PTR(-EBADF); - goto cleanup; - } - - btf = btf__new(data, read_cnt); - -cleanup: - free(data); - return btf; -} - /* * Probe few well-known locations for vmlinux kernel image and try to load BTF * data out of it to use for target BTF. @@ -3021,7 +3063,7 @@ struct btf *libbpf_find_kernel_btf(void) continue; if (locations[i].raw_btf) - btf = btf_load_raw(path); + btf = btf__parse_raw(path); else btf = btf__parse_elf(path, NULL); diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h index 491c7b41ffdc..f4a1a1d2b9a3 100644 --- a/tools/lib/bpf/btf.h +++ b/tools/lib/bpf/btf.h @@ -64,8 +64,9 @@ struct btf_ext_header { LIBBPF_API void btf__free(struct btf *btf); LIBBPF_API struct btf *btf__new(const void *data, __u32 size); -LIBBPF_API struct btf *btf__parse_elf(const char *path, - struct btf_ext **btf_ext); +LIBBPF_API struct btf *btf__parse(const char *path, struct btf_ext **btf_ext); +LIBBPF_API struct btf *btf__parse_elf(const char *path, struct btf_ext **btf_ext); +LIBBPF_API struct btf *btf__parse_raw(const char *path); LIBBPF_API int btf__finalize_data(struct bpf_object *obj, struct btf *btf); LIBBPF_API int btf__load(struct btf *btf); LIBBPF_API __s32 btf__find_by_name(const struct btf *btf, diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index 099863411f7d..0c4722bfdd0a 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -293,5 +293,7 @@ LIBBPF_0.1.0 { bpf_program__is_sk_lookup; bpf_program__set_autoload; bpf_program__set_sk_lookup; + btf__parse; + btf__parse_raw; btf__set_fd; } LIBBPF_0.0.9; -- cgit v1.2.3-58-ga151