From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751091AbdAWBMG (ORCPT ); Sun, 22 Jan 2017 20:12:06 -0500 Received: from relay6-d.mail.gandi.net ([217.70.183.198]:60282 "EHLO relay6-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751029AbdAWBMD (ORCPT ); Sun, 22 Jan 2017 20:12:03 -0500 X-Originating-IP: 208.91.1.34 From: Joe Stringer To: acme@kernel.org Cc: wangnan0@huawei.com, ast@fb.com, daniel@iogearbox.net, linux-kernel@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCHv2 perf/core 7/7] tools lib bpf: Add bpf_object__pin() Date: Sun, 22 Jan 2017 17:11:28 -0800 Message-Id: <20170123011128.26534-8-joe@ovn.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170123011128.26534-1-joe@ovn.org> References: <20170123011128.26534-1-joe@ovn.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add a new API to pin a BPF object to the filesystem. The user can specify the path full path within a BPF filesystem to pin the object. Programs will be pinned under a subdirectory 'progs', and maps will be pinned under a subdirectory 'maps'. For example, with the directory '/sys/fs/bpf/foo': /sys/fs/bpf/foo/progs/PROG_NAME /sys/fs/bpf/foo/maps/MAP_NAME Signed-off-by: Joe Stringer --- v2: Don't automount BPF filesystem Split program, map, object pinning into separate APIs and separate patches. --- tools/lib/bpf/libbpf.c | 73 ++++++++++++++++++++++++++++++++++++++++++++++++++ tools/lib/bpf/libbpf.h | 1 + 2 files changed, 74 insertions(+) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index c1d8b07e21d2..41645dc51fa1 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -36,6 +36,7 @@ #include #include #include +#include #include #include #include @@ -1335,6 +1336,78 @@ int bpf_map__pin(struct bpf_map *map, const char *path) return 0; } +static int make_dir(const char *path, const char *dir) +{ + char buf[PATH_MAX]; + int len, err = 0; + + len = snprintf(buf, PATH_MAX, "%s/%s", path, dir); + if (len < 0) + err = -EINVAL; + else if (len >= PATH_MAX) + err = -ENAMETOOLONG; + if (!err && mkdir(buf, 0700) && errno != EEXIST) + err = -errno; + + if (err) + pr_warning("failed to make dir %s/%s: %s\n", path, dir, + strerror(-err)); + return err; +} + +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, "maps"); + if (err) + return err; + + bpf_map__for_each(map, obj) { + char buf[PATH_MAX]; + int len; + + len = snprintf(buf, PATH_MAX, "%s/maps/%s", path, + bpf_map__name(map)); + if (len < 0 || len > PATH_MAX) + return -EINVAL; + + err = bpf_map__pin(map, buf); + if (err) + return err; + } + + err = make_dir(path, "progs"); + if (err) + return err; + + bpf_object__for_each_program(prog, obj) { + char buf[PATH_MAX]; + int len; + + len = snprintf(buf, PATH_MAX, "%s/progs/%s", path, + prog->section_name); + if (len < 0 || len > PATH_MAX) + return -EINVAL; + + 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 524247cfd205..8363ee6db4a0 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 */ -- 2.11.0