From f367540c8c13d65603c431e29a0b87a7db893d6c Mon Sep 17 00:00:00 2001 From: Joe Stringer Date: Thu, 26 Jan 2017 13:19:56 -0800 Subject: tools lib bpf: Add BPF program pinning APIs Add new APIs to pin a BPF program (or specific instances) to the filesystem. The user can specify the path full path within a BPF filesystem to pin the program. bpf_program__pin_instance(prog, path, n) will pin the nth instance of 'prog' to the specified path. bpf_program__pin(prog, path) will create the directory 'path' (if it does not exist) and pin each instance within that directory. For instance, path/0, path/1, path/2. Committer notes: - Add missing headers for mkdir() - Check strdup() for failure - Check snprintf >= size, not >, as == also means truncated, see 'man snprintf', return value. - Conditionally define BPF_FS_MAGIC, as it isn't in magic.h in older systems and we're not yet having a tools/include/uapi/linux/magic.h copy. - Do not include linux/magic.h, not present in older distros. Signed-off-by: Joe Stringer Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: Wang Nan Cc: netdev@vger.kernel.org Link: http://lkml.kernel.org/r/20170126212001.14103-2-joe@ovn.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/lib/bpf/libbpf.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'tools/lib/bpf/libbpf.h') diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 4014d1ba5e3d..9f8aa63b95f4 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -106,6 +106,9 @@ void *bpf_program__priv(struct bpf_program *prog); const char *bpf_program__title(struct bpf_program *prog, bool needs_copy); int bpf_program__fd(struct bpf_program *prog); +int bpf_program__pin_instance(struct bpf_program *prog, const char *path, + int instance); +int bpf_program__pin(struct bpf_program *prog, const char *path); struct bpf_insn; -- cgit v1.2.3 From b6989f35e80bf830f8dc97b74128d619faef0273 Mon Sep 17 00:00:00 2001 From: Joe Stringer Date: Thu, 26 Jan 2017 13:19:57 -0800 Subject: tools lib bpf: Add bpf_map__pin() Add a new API to pin a BPF map to the filesystem. The user can specify the path full path within a BPF filesystem to pin the map. Signed-off-by: Joe Stringer Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: Wang Nan Cc: netdev@vger.kernel.org Link: http://lkml.kernel.org/r/20170126212001.14103-3-joe@ovn.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/lib/bpf/libbpf.c | 22 ++++++++++++++++++++++ tools/lib/bpf/libbpf.h | 1 + 2 files changed, 23 insertions(+) (limited to 'tools/lib/bpf/libbpf.h') diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index c4465b2fddf6..6a8c8beeb291 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -1357,6 +1357,28 @@ int bpf_program__pin(struct bpf_program *prog, const char *path) return 0; } +int bpf_map__pin(struct bpf_map *map, const char *path) +{ + int err; + + err = check_path(path); + if (err) + return err; + + if (map == NULL) { + pr_warning("invalid map pointer\n"); + return -EINVAL; + } + + if (bpf_obj_pin(map->fd, path)) { + pr_warning("failed to pin map: %s\n", strerror(errno)); + return -errno; + } + + pr_debug("pinned map '%s'\n", path); + return 0; +} + void bpf_object__close(struct bpf_object *obj) { size_t i; diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 9f8aa63b95f4..2addf9d5b13c 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -236,6 +236,7 @@ typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *); int bpf_map__set_priv(struct bpf_map *map, void *priv, bpf_map_clear_priv_t clear_priv); void *bpf_map__priv(struct bpf_map *map); +int bpf_map__pin(struct bpf_map *map, const char *path); long libbpf_get_error(const void *ptr); -- cgit v1.2.3 From d5148d8554d08f03b3e34ecc286ab1729c35c24c Mon Sep 17 00:00:00 2001 From: Joe Stringer Date: Thu, 26 Jan 2017 13:19:58 -0800 Subject: tools lib bpf: Add bpf_object__pin() Add a new API to pin a BPF object to the filesystem. The user can specify the path within a BPF filesystem to pin the object. Programs will be pinned under a subdirectory named the same as the program, with each instance appearing as a numbered file under that directory, and maps will be pinned under the path using the name of the map as the file basename. For example, with the directory '/sys/fs/bpf/foo' and a BPF object which contains two instances of a program named 'bar', and a map named 'baz': /sys/fs/bpf/foo/bar/0 /sys/fs/bpf/foo/bar/1 /sys/fs/bpf/foo/baz Signed-off-by: Joe Stringer Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: Wang Nan Cc: netdev@vger.kernel.org Link: http://lkml.kernel.org/r/20170126212001.14103-4-joe@ovn.org [ Check snprintf >= for truncation, as snprintf(bf, size, ...) == size also means truncation ] Signed-off-by: Arnaldo Carvalho de Melo --- tools/lib/bpf/libbpf.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++++++ tools/lib/bpf/libbpf.h | 1 + 2 files changed, 54 insertions(+) (limited to 'tools/lib/bpf/libbpf.h') diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 6a8c8beeb291..ac6eb863b2a4 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -1379,6 +1379,59 @@ int bpf_map__pin(struct bpf_map *map, const char *path) return 0; } +int bpf_object__pin(struct bpf_object *obj, const char *path) +{ + struct bpf_program *prog; + struct bpf_map *map; + int err; + + if (!obj) + return -ENOENT; + + if (!obj->loaded) { + pr_warning("object not yet loaded; load it first\n"); + return -ENOENT; + } + + err = make_dir(path); + if (err) + return err; + + bpf_map__for_each(map, obj) { + char buf[PATH_MAX]; + int len; + + len = snprintf(buf, PATH_MAX, "%s/%s", path, + bpf_map__name(map)); + if (len < 0) + return -EINVAL; + else if (len >= PATH_MAX) + return -ENAMETOOLONG; + + err = bpf_map__pin(map, buf); + if (err) + return err; + } + + bpf_object__for_each_program(prog, obj) { + char buf[PATH_MAX]; + int len; + + len = snprintf(buf, PATH_MAX, "%s/%s", path, + prog->section_name); + if (len < 0) + return -EINVAL; + else if (len >= PATH_MAX) + return -ENAMETOOLONG; + + err = bpf_program__pin(prog, buf); + if (err) + return err; + } + + return 0; +} + void bpf_object__close(struct bpf_object *obj) { size_t i; diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 2addf9d5b13c..b30394f9947a 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -65,6 +65,7 @@ struct bpf_object *bpf_object__open(const char *path); struct bpf_object *bpf_object__open_buffer(void *obj_buf, size_t obj_buf_sz, const char *name); +int bpf_object__pin(struct bpf_object *object, const char *path); void bpf_object__close(struct bpf_object *object); /* Load/unload object into/from kernel */ -- cgit v1.2.3