diff options
| -rw-r--r-- | tools/bpf/bpftool/cfg.c | 147 | ||||
| -rw-r--r-- | tools/bpf/bpftool/cfg.h | 43 |
2 files changed, 190 insertions, 0 deletions
diff --git a/tools/bpf/bpftool/cfg.c b/tools/bpf/bpftool/cfg.c new file mode 100644 index 000000000000..8330dedb3576 --- /dev/null +++ b/tools/bpf/bpftool/cfg.c @@ -0,0 +1,147 @@ +// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +/* + * Copyright (C) 2018 Netronome Systems, Inc. + * + * This software is dual licensed under the GNU General License Version 2, + * June 1991 as shown in the file COPYING in the top-level directory of this + * source tree or the BSD 2-Clause License provided below. You have the + * option to license this software under the complete terms of either license. + * + * The BSD 2-Clause License: + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * 1. Redistributions of source code must retain the above + * copyright notice, this list of conditions and the following + * disclaimer. + * + * 2. Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#include <linux/list.h> +#include <stdlib.h> +#include <string.h> + +#include "cfg.h" +#include "main.h" + +struct cfg { + struct list_head funcs; + int func_num; +}; + +struct func_node { + struct list_head l; + struct bpf_insn *start; + struct bpf_insn *end; + int idx; +}; + +#define func_prev(func) list_prev_entry(func, l) +#define func_next(func) list_next_entry(func, l) +#define cfg_first_func(cfg) \ + list_first_entry(&cfg->funcs, struct func_node, l) +#define cfg_last_func(cfg) \ + list_last_entry(&cfg->funcs, struct func_node, l) + +static struct func_node *cfg_append_func(struct cfg *cfg, struct bpf_insn *insn) +{ + struct func_node *new_func, *func; + + list_for_each_entry(func, &cfg->funcs, l) { + if (func->start == insn) + return func; + else if (func->start > insn) + break; + } + + func = func_prev(func); + new_func = calloc(1, sizeof(*new_func)); + if (!new_func) { + p_err("OOM when allocating FUNC node"); + return NULL; + } + new_func->start = insn; + new_func->idx = cfg->func_num; + list_add(&new_func->l, &func->l); + cfg->func_num++; + + return new_func; +} + +static bool cfg_partition_funcs(struct cfg *cfg, struct bpf_insn *cur, + struct bpf_insn *end) +{ + struct func_node *func, *last_func; + + func = cfg_append_func(cfg, cur); + if (!func) + return true; + + for (; cur < end; cur++) { + if (cur->code != (BPF_JMP | BPF_CALL)) + continue; + if (cur->src_reg != BPF_PSEUDO_CALL) + continue; + func = cfg_append_func(cfg, cur + cur->off + 1); + if (!func) + return true; + } + + last_func = cfg_last_func(cfg); + last_func->end = end - 1; + func = cfg_first_func(cfg); + list_for_each_entry_from(func, &last_func->l, l) { + func->end = func_next(func)->start - 1; + } + + return false; +} + +static bool cfg_build(struct cfg *cfg, struct bpf_insn *insn, unsigned int len) +{ + int cnt = len / sizeof(*insn); + + INIT_LIST_HEAD(&cfg->funcs); + + return cfg_partition_funcs(cfg, insn, insn + cnt); +} + +static void cfg_destroy(struct cfg *cfg) +{ + struct func_node *func, *func2; + + list_for_each_entry_safe(func, func2, &cfg->funcs, l) { + list_del(&func->l); + free(func); + } +} + +void dump_xlated_cfg(void *buf, unsigned int len) +{ + struct bpf_insn *insn = buf; + struct cfg cfg; + + memset(&cfg, 0, sizeof(cfg)); + if (cfg_build(&cfg, insn, len)) + return; + + cfg_destroy(&cfg); +} diff --git a/tools/bpf/bpftool/cfg.h b/tools/bpf/bpftool/cfg.h new file mode 100644 index 000000000000..2cc9bd990b13 --- /dev/null +++ b/tools/bpf/bpftool/cfg.h @@ -0,0 +1,43 @@ +// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +/* + * Copyright (C) 2018 Netronome Systems, Inc. + * + * This software is dual licensed under the GNU General License Version 2, + * June 1991 as shown in the file COPYING in the top-level directory of this + * source tree or the BSD 2-Clause License provided below. You have the + * option to license this software under the complete terms of either license. + * + * The BSD 2-Clause License: + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * 1. Redistributions of source code must retain the above + * copyright notice, this list of conditions and the following + * disclaimer. + * + * 2. Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#ifndef __BPF_TOOL_CFG_H +#define __BPF_TOOL_CFG_H + +void dump_xlated_cfg(void *buf, unsigned int len); + +#endif /* __BPF_TOOL_CFG_H */ |