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 + 1 file changed, 1 insertion(+) (limited to 'tools/lib/bpf/bpf.c') 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)); } -- 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/bpf.c') 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/bpf.c') 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