From 1bdb6c9a1c43fdf9b83b2331dfc6229bd2e71d9b Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Sat, 20 Jun 2020 23:21:12 -0700 Subject: libbpf: Add a bunch of attribute getters/setters for map definitions MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add a bunch of getter for various aspects of BPF map. Some of these attribute (e.g., key_size, value_size, type, etc) are available right now in struct bpf_map_def, but this patch adds getter allowing to fetch them individually. bpf_map_def approach isn't very scalable, when ABI stability requirements are taken into account. It's much easier to extend libbpf and add support for new features, when each aspect of BPF map has separate getter/setter. Getters follow the common naming convention of not explicitly having "get" in its name: bpf_map__type() returns map type, bpf_map__key_size() returns key_size. Setters, though, explicitly have set in their name: bpf_map__set_type(), bpf_map__set_key_size(). This patch ensures we now have a getter and a setter for the following map attributes: - type; - max_entries; - map_flags; - numa_node; - key_size; - value_size; - ifindex. bpf_map__resize() enforces unnecessary restriction of max_entries > 0. It is unnecessary, because libbpf actually supports zero max_entries for some cases (e.g., for PERF_EVENT_ARRAY map) and treats it specially during map creation time. To allow setting max_entries=0, new bpf_map__set_max_entries() setter is added. bpf_map__resize()'s behavior is preserved for backwards compatibility reasons. Map ifindex getter is added as well. There is a setter already, but no corresponding getter. Fix this assymetry as well. bpf_map__set_ifindex() itself is converted from void function into error-returning one, similar to other setters. The only error returned right now is -EBUSY, if BPF map is already loaded and has corresponding FD. One lacking attribute with no ability to get/set or even specify it declaratively is numa_node. This patch fixes this gap and both adds programmatic getter/setter, as well as adds support for numa_node field in BTF-defined map. Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Acked-by: Toke Høiland-Jørgensen Link: https://lore.kernel.org/bpf/20200621062112.3006313-1-andriin@fb.com --- tools/lib/bpf/libbpf.h | 30 +++++++++++++++++++++++++++--- 1 file changed, 27 insertions(+), 3 deletions(-) (limited to 'tools/lib/bpf/libbpf.h') diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 334437af3014..fdd279fb1866 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -418,11 +418,38 @@ bpf_map__next(const struct bpf_map *map, const struct bpf_object *obj); LIBBPF_API struct bpf_map * bpf_map__prev(const struct bpf_map *map, const struct bpf_object *obj); +/* get/set map FD */ LIBBPF_API int bpf_map__fd(const struct bpf_map *map); +LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd); +/* get map definition */ LIBBPF_API const struct bpf_map_def *bpf_map__def(const struct bpf_map *map); +/* get map name */ LIBBPF_API const char *bpf_map__name(const struct bpf_map *map); +/* get/set map type */ +LIBBPF_API enum bpf_map_type bpf_map__type(const struct bpf_map *map); +LIBBPF_API int bpf_map__set_type(struct bpf_map *map, enum bpf_map_type type); +/* get/set map size (max_entries) */ +LIBBPF_API __u32 bpf_map__max_entries(const struct bpf_map *map); +LIBBPF_API int bpf_map__set_max_entries(struct bpf_map *map, __u32 max_entries); +LIBBPF_API int bpf_map__resize(struct bpf_map *map, __u32 max_entries); +/* get/set map flags */ +LIBBPF_API __u32 bpf_map__map_flags(const struct bpf_map *map); +LIBBPF_API int bpf_map__set_map_flags(struct bpf_map *map, __u32 flags); +/* get/set map NUMA node */ +LIBBPF_API __u32 bpf_map__numa_node(const struct bpf_map *map); +LIBBPF_API int bpf_map__set_numa_node(struct bpf_map *map, __u32 numa_node); +/* get/set map key size */ +LIBBPF_API __u32 bpf_map__key_size(const struct bpf_map *map); +LIBBPF_API int bpf_map__set_key_size(struct bpf_map *map, __u32 size); +/* get/set map value size */ +LIBBPF_API __u32 bpf_map__value_size(const struct bpf_map *map); +LIBBPF_API int bpf_map__set_value_size(struct bpf_map *map, __u32 size); +/* get map key/value BTF type IDs */ LIBBPF_API __u32 bpf_map__btf_key_type_id(const struct bpf_map *map); LIBBPF_API __u32 bpf_map__btf_value_type_id(const struct bpf_map *map); +/* get/set map if_index */ +LIBBPF_API __u32 bpf_map__ifindex(const struct bpf_map *map); +LIBBPF_API int bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex); typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *); LIBBPF_API int bpf_map__set_priv(struct bpf_map *map, void *priv, @@ -430,11 +457,8 @@ LIBBPF_API int bpf_map__set_priv(struct bpf_map *map, void *priv, LIBBPF_API void *bpf_map__priv(const struct bpf_map *map); LIBBPF_API int bpf_map__set_initial_value(struct bpf_map *map, const void *data, size_t size); -LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd); -LIBBPF_API int bpf_map__resize(struct bpf_map *map, __u32 max_entries); LIBBPF_API bool bpf_map__is_offload_neutral(const struct bpf_map *map); LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map); -LIBBPF_API void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex); LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path); LIBBPF_API const char *bpf_map__get_pin_path(const struct bpf_map *map); LIBBPF_API bool bpf_map__is_pinned(const struct bpf_map *map); -- cgit v1.2.3 From d929758101fc0674008169dc1de963e3181c587b Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Thu, 25 Jun 2020 16:26:28 -0700 Subject: libbpf: Support disabling auto-loading BPF programs Currently, bpf_object__load() (and by induction skeleton's load), will always attempt to prepare, relocate, and load into kernel every single BPF program found inside the BPF object file. This is often convenient and the right thing to do and what users expect. But there are plenty of cases (especially with BPF development constantly picking up the pace), where BPF application is intended to work with old kernels, with potentially reduced set of features. But on kernels supporting extra features, it would like to take a full advantage of them, by employing extra BPF program. This could be a choice of using fentry/fexit over kprobe/kretprobe, if kernel is recent enough and is built with BTF. Or BPF program might be providing optimized bpf_iter-based solution that user-space might want to use, whenever available. And so on. With libbpf and BPF CO-RE in particular, it's advantageous to not have to maintain two separate BPF object files to achieve this. So to enable such use cases, this patch adds ability to request not auto-loading chosen BPF programs. In such case, libbpf won't attempt to perform relocations (which might fail due to old kernel), won't try to resolve BTF types for BTF-aware (tp_btf/fentry/fexit/etc) program types, because BTF might not be present, and so on. Skeleton will also automatically skip auto-attachment step for such not loaded BPF programs. Overall, this feature allows to simplify development and deployment of real-world BPF applications with complicated compatibility requirements. Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200625232629.3444003-2-andriin@fb.com --- tools/lib/bpf/libbpf.c | 48 ++++++++++++++++++++++++++++++++++++++++-------- tools/lib/bpf/libbpf.h | 2 ++ tools/lib/bpf/libbpf.map | 2 ++ 3 files changed, 44 insertions(+), 8 deletions(-) (limited to 'tools/lib/bpf/libbpf.h') diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 6b4955d170ff..4ea7f4f1a691 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -230,6 +230,7 @@ struct bpf_program { struct bpf_insn *insns; size_t insns_cnt, main_prog_cnt; enum bpf_prog_type type; + bool load; struct reloc_desc *reloc_desc; int nr_reloc; @@ -541,6 +542,7 @@ bpf_program__init(void *data, size_t size, char *section_name, int idx, prog->instances.fds = NULL; prog->instances.nr = -1; prog->type = BPF_PROG_TYPE_UNSPEC; + prog->load = true; return 0; errout: @@ -2513,6 +2515,8 @@ static int bpf_object__load_vmlinux_btf(struct bpf_object *obj) need_vmlinux_btf = true; bpf_object__for_each_program(prog, obj) { + if (!prog->load) + continue; if (libbpf_prog_needs_vmlinux_btf(prog)) { need_vmlinux_btf = true; break; @@ -5445,6 +5449,12 @@ int bpf_program__load(struct bpf_program *prog, char *license, __u32 kern_ver) { int err = 0, fd, i, btf_id; + if (prog->obj->loaded) { + pr_warn("prog '%s'('%s'): can't load after object was loaded\n", + prog->name, prog->section_name); + return -EINVAL; + } + if ((prog->type == BPF_PROG_TYPE_TRACING || prog->type == BPF_PROG_TYPE_LSM || prog->type == BPF_PROG_TYPE_EXT) && !prog->attach_btf_id) { @@ -5533,16 +5543,21 @@ static bool bpf_program__is_function_storage(const struct bpf_program *prog, static int bpf_object__load_progs(struct bpf_object *obj, int log_level) { + struct bpf_program *prog; size_t i; int err; for (i = 0; i < obj->nr_programs; i++) { - if (bpf_program__is_function_storage(&obj->programs[i], obj)) + prog = &obj->programs[i]; + if (bpf_program__is_function_storage(prog, obj)) continue; - obj->programs[i].log_level |= log_level; - err = bpf_program__load(&obj->programs[i], - obj->license, - obj->kern_version); + if (!prog->load) { + pr_debug("prog '%s'('%s'): skipped loading\n", + prog->name, prog->section_name); + continue; + } + prog->log_level |= log_level; + err = bpf_program__load(prog, obj->license, obj->kern_version); if (err) return err; } @@ -5869,12 +5884,10 @@ int bpf_object__load_xattr(struct bpf_object_load_attr *attr) return -EINVAL; if (obj->loaded) { - pr_warn("object should not be loaded twice\n"); + pr_warn("object '%s': load can't be attempted twice\n", obj->name); return -EINVAL; } - obj->loaded = true; - err = bpf_object__probe_loading(obj); err = err ? : bpf_object__probe_caps(obj); err = err ? : bpf_object__resolve_externs(obj, obj->kconfig); @@ -5889,6 +5902,8 @@ int bpf_object__load_xattr(struct bpf_object_load_attr *attr) btf__free(obj->btf_vmlinux); obj->btf_vmlinux = NULL; + obj->loaded = true; /* doesn't matter if successfully or not */ + if (err) goto out; @@ -6661,6 +6676,20 @@ const char *bpf_program__title(const struct bpf_program *prog, bool needs_copy) return title; } +bool bpf_program__autoload(const struct bpf_program *prog) +{ + return prog->load; +} + +int bpf_program__set_autoload(struct bpf_program *prog, bool autoload) +{ + if (prog->obj->loaded) + return -EINVAL; + + prog->load = autoload; + return 0; +} + int bpf_program__fd(const struct bpf_program *prog) { return bpf_program__nth_fd(prog, 0); @@ -9283,6 +9312,9 @@ int bpf_object__attach_skeleton(struct bpf_object_skeleton *s) const struct bpf_sec_def *sec_def; const char *sec_name = bpf_program__title(prog, false); + if (!prog->load) + continue; + sec_def = find_sec_def(sec_name); if (!sec_def || !sec_def->attach_fn) continue; diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index fdd279fb1866..2335971ed0bd 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -200,6 +200,8 @@ LIBBPF_API void bpf_program__set_ifindex(struct bpf_program *prog, LIBBPF_API const char *bpf_program__name(const struct bpf_program *prog); LIBBPF_API const char *bpf_program__title(const struct bpf_program *prog, bool needs_copy); +LIBBPF_API bool bpf_program__autoload(const struct bpf_program *prog); +LIBBPF_API int bpf_program__set_autoload(struct bpf_program *prog, bool autoload); /* returns program size in bytes */ LIBBPF_API size_t bpf_program__size(const struct bpf_program *prog); diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index 9914e0db4859..6544d2cd1ed6 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -286,4 +286,6 @@ LIBBPF_0.1.0 { bpf_map__set_value_size; bpf_map__type; bpf_map__value_size; + bpf_program__autoload; + bpf_program__set_autoload; } LIBBPF_0.0.9; -- cgit v1.2.3 From 499dd29d90bb78d4ac4f0d6648e26f4a339829b1 Mon Sep 17 00:00:00 2001 From: Jakub Sitnicki Date: Fri, 17 Jul 2020 12:35:33 +0200 Subject: libbpf: Add support for SK_LOOKUP program type Make libbpf aware of the newly added program type, and assign it a section name. Signed-off-by: Jakub Sitnicki Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200717103536.397595-13-jakub@cloudflare.com --- tools/lib/bpf/libbpf.c | 3 +++ tools/lib/bpf/libbpf.h | 2 ++ tools/lib/bpf/libbpf.map | 2 ++ tools/lib/bpf/libbpf_probes.c | 3 +++ 4 files changed, 10 insertions(+) (limited to 'tools/lib/bpf/libbpf.h') diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index f55fd8a5c008..846164c79df1 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -6799,6 +6799,7 @@ BPF_PROG_TYPE_FNS(perf_event, BPF_PROG_TYPE_PERF_EVENT); BPF_PROG_TYPE_FNS(tracing, BPF_PROG_TYPE_TRACING); BPF_PROG_TYPE_FNS(struct_ops, BPF_PROG_TYPE_STRUCT_OPS); BPF_PROG_TYPE_FNS(extension, BPF_PROG_TYPE_EXT); +BPF_PROG_TYPE_FNS(sk_lookup, BPF_PROG_TYPE_SK_LOOKUP); enum bpf_attach_type bpf_program__get_expected_attach_type(struct bpf_program *prog) @@ -6981,6 +6982,8 @@ static const struct bpf_sec_def section_defs[] = { BPF_EAPROG_SEC("cgroup/setsockopt", BPF_PROG_TYPE_CGROUP_SOCKOPT, BPF_CGROUP_SETSOCKOPT), BPF_PROG_SEC("struct_ops", BPF_PROG_TYPE_STRUCT_OPS), + BPF_EAPROG_SEC("sk_lookup/", BPF_PROG_TYPE_SK_LOOKUP, + BPF_SK_LOOKUP), }; #undef BPF_PROG_SEC_IMPL diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 2335971ed0bd..c2272132e929 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -350,6 +350,7 @@ LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog); LIBBPF_API int bpf_program__set_tracing(struct bpf_program *prog); LIBBPF_API int bpf_program__set_struct_ops(struct bpf_program *prog); LIBBPF_API int bpf_program__set_extension(struct bpf_program *prog); +LIBBPF_API int bpf_program__set_sk_lookup(struct bpf_program *prog); LIBBPF_API enum bpf_prog_type bpf_program__get_type(struct bpf_program *prog); LIBBPF_API void bpf_program__set_type(struct bpf_program *prog, @@ -377,6 +378,7 @@ LIBBPF_API bool bpf_program__is_perf_event(const struct bpf_program *prog); LIBBPF_API bool bpf_program__is_tracing(const struct bpf_program *prog); LIBBPF_API bool bpf_program__is_struct_ops(const struct bpf_program *prog); LIBBPF_API bool bpf_program__is_extension(const struct bpf_program *prog); +LIBBPF_API bool bpf_program__is_sk_lookup(const struct bpf_program *prog); /* * No need for __attribute__((packed)), all members of 'bpf_map_def' diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index c5d5c7664c3b..6f0856abe299 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -287,6 +287,8 @@ LIBBPF_0.1.0 { bpf_map__type; bpf_map__value_size; bpf_program__autoload; + bpf_program__is_sk_lookup; bpf_program__set_autoload; + bpf_program__set_sk_lookup; btf__set_fd; } LIBBPF_0.0.9; diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c index 10cd8d1891f5..5a3d3f078408 100644 --- a/tools/lib/bpf/libbpf_probes.c +++ b/tools/lib/bpf/libbpf_probes.c @@ -78,6 +78,9 @@ probe_load(enum bpf_prog_type prog_type, const struct bpf_insn *insns, case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: xattr.expected_attach_type = BPF_CGROUP_INET4_CONNECT; break; + case BPF_PROG_TYPE_SK_LOOKUP: + xattr.expected_attach_type = BPF_SK_LOOKUP; + break; case BPF_PROG_TYPE_KPROBE: xattr.kern_version = get_kernel_version(); break; -- cgit v1.2.3 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/bpf/libbpf.h') 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 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/bpf/libbpf.h') 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 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/bpf/libbpf.h') 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 From 74fc097de327b37e8fe3ff580ce7ffaa7c1740dd Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Tue, 4 Aug 2020 22:50:58 -0700 Subject: tools/bpf: Support new uapi for map element bpf iterator Previous commit adjusted kernel uapi for map element bpf iterator. This patch adjusted libbpf API due to uapi change. bpftool and bpf_iter selftests are also changed accordingly. Signed-off-by: Yonghong Song Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Acked-by: John Fastabend Link: https://lore.kernel.org/bpf/20200805055058.1457623-1-yhs@fb.com --- tools/bpf/bpftool/iter.c | 9 +++-- tools/include/uapi/linux/bpf.h | 15 +++++---- tools/lib/bpf/bpf.c | 3 ++ tools/lib/bpf/bpf.h | 5 ++- tools/lib/bpf/libbpf.c | 6 ++-- tools/lib/bpf/libbpf.h | 5 +-- tools/testing/selftests/bpf/prog_tests/bpf_iter.c | 40 ++++++++++++++++++----- 7 files changed, 58 insertions(+), 25 deletions(-) (limited to 'tools/lib/bpf/libbpf.h') diff --git a/tools/bpf/bpftool/iter.c b/tools/bpf/bpftool/iter.c index c9dba7543dba..3b1aad7535dd 100644 --- a/tools/bpf/bpftool/iter.c +++ b/tools/bpf/bpftool/iter.c @@ -11,6 +11,7 @@ static int do_pin(int argc, char **argv) { DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, iter_opts); + union bpf_iter_link_info linfo; const char *objfile, *path; struct bpf_program *prog; struct bpf_object *obj; @@ -36,6 +37,11 @@ static int do_pin(int argc, char **argv) map_fd = map_parse_fd(&argc, &argv); if (map_fd < 0) return -1; + + memset(&linfo, 0, sizeof(linfo)); + linfo.map.map_fd = map_fd; + iter_opts.link_info = &linfo; + iter_opts.link_info_len = sizeof(linfo); } } @@ -57,9 +63,6 @@ static int do_pin(int argc, char **argv) goto close_obj; } - if (map_fd >= 0) - iter_opts.map_fd = map_fd; - link = bpf_program__attach_iter(prog, &iter_opts); if (IS_ERR(link)) { err = PTR_ERR(link); diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index b134e679e9db..0480f893facd 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -81,6 +81,12 @@ struct bpf_cgroup_storage_key { __u32 attach_type; /* program attach type */ }; +union bpf_iter_link_info { + struct { + __u32 map_fd; + } map; +}; + /* BPF syscall commands, see bpf(2) man-page for details. */ enum bpf_cmd { BPF_MAP_CREATE, @@ -249,13 +255,6 @@ enum bpf_link_type { MAX_BPF_LINK_TYPE, }; -enum bpf_iter_link_info { - BPF_ITER_LINK_UNSPEC = 0, - BPF_ITER_LINK_MAP_FD = 1, - - MAX_BPF_ITER_LINK_INFO, -}; - /* cgroup-bpf attach flags used in BPF_PROG_ATTACH command * * NONE(default): No further bpf programs allowed in the subtree. @@ -623,6 +622,8 @@ union bpf_attr { }; __u32 attach_type; /* attach type */ __u32 flags; /* extra flags */ + __aligned_u64 iter_info; /* extra bpf_iter_link_info */ + __u32 iter_info_len; /* iter_info length */ } link_create; struct { /* struct used by BPF_LINK_UPDATE command */ diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index eab14c97c15d..0750681057c2 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -599,6 +599,9 @@ int bpf_link_create(int prog_fd, int target_fd, attr.link_create.target_fd = target_fd; attr.link_create.attach_type = attach_type; attr.link_create.flags = OPTS_GET(opts, flags, 0); + attr.link_create.iter_info = + ptr_to_u64(OPTS_GET(opts, iter_info, (void *)0)); + attr.link_create.iter_info_len = OPTS_GET(opts, iter_info_len, 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 28855fd5b5f4..015d13f25fcc 100644 --- a/tools/lib/bpf/bpf.h +++ b/tools/lib/bpf/bpf.h @@ -168,11 +168,14 @@ LIBBPF_API int bpf_prog_detach(int attachable_fd, enum bpf_attach_type type); LIBBPF_API int bpf_prog_detach2(int prog_fd, int attachable_fd, enum bpf_attach_type type); +union bpf_iter_link_info; /* defined in up-to-date linux/bpf.h */ struct bpf_link_create_opts { size_t sz; /* size of this struct for forward/backward compatibility */ __u32 flags; + union bpf_iter_link_info *iter_info; + __u32 iter_info_len; }; -#define bpf_link_create_opts__last_field flags +#define bpf_link_create_opts__last_field iter_info_len 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 7be04e45d29c..0a06124f7999 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -8306,10 +8306,8 @@ bpf_program__attach_iter(struct bpf_program *prog, 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; - } + link_create_opts.iter_info = OPTS_GET(opts, link_info, (void *)0); + link_create_opts.iter_info_len = OPTS_GET(opts, link_info_len, 0); prog_fd = bpf_program__fd(prog); if (prog_fd < 0) { diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 3ed1399bfbbc..5ecb4069a9f0 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -267,9 +267,10 @@ 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; + union bpf_iter_link_info *link_info; + __u32 link_info_len; }; -#define bpf_iter_attach_opts__last_field map_fd +#define bpf_iter_attach_opts__last_field link_info_len LIBBPF_API struct bpf_link * bpf_program__attach_iter(struct bpf_program *prog, diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c index 4ffefdc1130f..7375d9a6d242 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c @@ -468,6 +468,7 @@ static void test_bpf_hash_map(void) DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts); struct bpf_iter_bpf_hash_map *skel; int err, i, len, map_fd, iter_fd; + union bpf_iter_link_info linfo; __u64 val, expected_val = 0; struct bpf_link *link; struct key_t { @@ -490,13 +491,16 @@ static void test_bpf_hash_map(void) goto out; /* iterator with hashmap2 and hashmap3 should fail */ - opts.map_fd = bpf_map__fd(skel->maps.hashmap2); + memset(&linfo, 0, sizeof(linfo)); + linfo.map.map_fd = bpf_map__fd(skel->maps.hashmap2); + opts.link_info = &linfo; + opts.link_info_len = sizeof(linfo); link = bpf_program__attach_iter(skel->progs.dump_bpf_hash_map, &opts); if (CHECK(!IS_ERR(link), "attach_iter", "attach_iter for hashmap2 unexpected succeeded\n")) goto out; - opts.map_fd = bpf_map__fd(skel->maps.hashmap3); + linfo.map.map_fd = bpf_map__fd(skel->maps.hashmap3); link = bpf_program__attach_iter(skel->progs.dump_bpf_hash_map, &opts); if (CHECK(!IS_ERR(link), "attach_iter", "attach_iter for hashmap3 unexpected succeeded\n")) @@ -519,7 +523,7 @@ static void test_bpf_hash_map(void) goto out; } - opts.map_fd = map_fd; + linfo.map.map_fd = map_fd; link = bpf_program__attach_iter(skel->progs.dump_bpf_hash_map, &opts); if (CHECK(IS_ERR(link), "attach_iter", "attach_iter failed\n")) goto out; @@ -562,6 +566,7 @@ static void test_bpf_percpu_hash_map(void) DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts); struct bpf_iter_bpf_percpu_hash_map *skel; int err, i, j, len, map_fd, iter_fd; + union bpf_iter_link_info linfo; __u32 expected_val = 0; struct bpf_link *link; struct key_t { @@ -606,7 +611,10 @@ static void test_bpf_percpu_hash_map(void) goto out; } - opts.map_fd = map_fd; + memset(&linfo, 0, sizeof(linfo)); + linfo.map.map_fd = map_fd; + opts.link_info = &linfo; + opts.link_info_len = sizeof(linfo); link = bpf_program__attach_iter(skel->progs.dump_bpf_percpu_hash_map, &opts); if (CHECK(IS_ERR(link), "attach_iter", "attach_iter failed\n")) goto out; @@ -649,6 +657,7 @@ static void test_bpf_array_map(void) DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts); __u32 expected_key = 0, res_first_key; struct bpf_iter_bpf_array_map *skel; + union bpf_iter_link_info linfo; int err, i, map_fd, iter_fd; struct bpf_link *link; char buf[64] = {}; @@ -673,7 +682,10 @@ static void test_bpf_array_map(void) goto out; } - opts.map_fd = map_fd; + memset(&linfo, 0, sizeof(linfo)); + linfo.map.map_fd = map_fd; + opts.link_info = &linfo; + opts.link_info_len = sizeof(linfo); link = bpf_program__attach_iter(skel->progs.dump_bpf_array_map, &opts); if (CHECK(IS_ERR(link), "attach_iter", "attach_iter failed\n")) goto out; @@ -730,6 +742,7 @@ static void test_bpf_percpu_array_map(void) DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts); struct bpf_iter_bpf_percpu_array_map *skel; __u32 expected_key = 0, expected_val = 0; + union bpf_iter_link_info linfo; int err, i, j, map_fd, iter_fd; struct bpf_link *link; char buf[64]; @@ -765,7 +778,10 @@ static void test_bpf_percpu_array_map(void) goto out; } - opts.map_fd = map_fd; + memset(&linfo, 0, sizeof(linfo)); + linfo.map.map_fd = map_fd; + opts.link_info = &linfo; + opts.link_info_len = sizeof(linfo); link = bpf_program__attach_iter(skel->progs.dump_bpf_percpu_array_map, &opts); if (CHECK(IS_ERR(link), "attach_iter", "attach_iter failed\n")) goto out; @@ -803,6 +819,7 @@ static void test_bpf_sk_storage_map(void) DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts); int err, i, len, map_fd, iter_fd, num_sockets; struct bpf_iter_bpf_sk_storage_map *skel; + union bpf_iter_link_info linfo; int sock_fd[3] = {-1, -1, -1}; __u32 val, expected_val = 0; struct bpf_link *link; @@ -829,7 +846,10 @@ static void test_bpf_sk_storage_map(void) goto out; } - opts.map_fd = map_fd; + memset(&linfo, 0, sizeof(linfo)); + linfo.map.map_fd = map_fd; + opts.link_info = &linfo; + opts.link_info_len = sizeof(linfo); link = bpf_program__attach_iter(skel->progs.dump_bpf_sk_storage_map, &opts); if (CHECK(IS_ERR(link), "attach_iter", "attach_iter failed\n")) goto out; @@ -871,6 +891,7 @@ static void test_rdonly_buf_out_of_bound(void) { DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts); struct bpf_iter_test_kern5 *skel; + union bpf_iter_link_info linfo; struct bpf_link *link; skel = bpf_iter_test_kern5__open_and_load(); @@ -878,7 +899,10 @@ static void test_rdonly_buf_out_of_bound(void) "skeleton open_and_load failed\n")) return; - opts.map_fd = bpf_map__fd(skel->maps.hashmap1); + memset(&linfo, 0, sizeof(linfo)); + linfo.map.map_fd = bpf_map__fd(skel->maps.hashmap1); + opts.link_info = &linfo; + opts.link_info_len = sizeof(linfo); link = bpf_program__attach_iter(skel->progs.dump_bpf_hash_map, &opts); if (CHECK(!IS_ERR(link), "attach_iter", "unexpected success\n")) bpf_link__destroy(link); -- cgit v1.2.3