2 * common eBPF ELF operations.
4 * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
5 * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
6 * Copyright (C) 2015 Huawei Inc.
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation;
11 * version 2.1 of the License (not later!)
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this program; if not, see <http://www.gnu.org/licenses>
25 #include <asm/unistd.h>
26 #include <linux/bpf.h>
30 * When building perf, unistd.h is overrided. __NR_bpf is
31 * required to be defined explicitly.
34 # if defined(__i386__)
36 # elif defined(__x86_64__)
38 # elif defined(__aarch64__)
41 # error __NR_bpf not defined. libbpf does not support your arch.
45 static __u64 ptr_to_u64(void *ptr)
47 return (__u64) (unsigned long) ptr;
50 static int sys_bpf(enum bpf_cmd cmd, union bpf_attr *attr,
53 return syscall(__NR_bpf, cmd, attr, size);
56 int bpf_create_map(enum bpf_map_type map_type, int key_size,
57 int value_size, int max_entries, __u32 map_flags)
61 memset(&attr, '\0', sizeof(attr));
63 attr.map_type = map_type;
64 attr.key_size = key_size;
65 attr.value_size = value_size;
66 attr.max_entries = max_entries;
67 attr.map_flags = map_flags;
69 return sys_bpf(BPF_MAP_CREATE, &attr, sizeof(attr));
72 int bpf_load_program(enum bpf_prog_type type, struct bpf_insn *insns,
73 size_t insns_cnt, char *license,
74 __u32 kern_version, char *log_buf, size_t log_buf_sz)
79 bzero(&attr, sizeof(attr));
80 attr.prog_type = type;
81 attr.insn_cnt = (__u32)insns_cnt;
82 attr.insns = ptr_to_u64(insns);
83 attr.license = ptr_to_u64(license);
84 attr.log_buf = ptr_to_u64(NULL);
87 attr.kern_version = kern_version;
89 fd = sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr));
90 if (fd >= 0 || !log_buf || !log_buf_sz)
93 /* Try again with log */
94 attr.log_buf = ptr_to_u64(log_buf);
95 attr.log_size = log_buf_sz;
98 return sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr));
101 int bpf_map_update_elem(int fd, void *key, void *value,
106 bzero(&attr, sizeof(attr));
108 attr.key = ptr_to_u64(key);
109 attr.value = ptr_to_u64(value);
112 return sys_bpf(BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr));
115 int bpf_map_lookup_elem(int fd, void *key, void *value)
119 bzero(&attr, sizeof(attr));
121 attr.key = ptr_to_u64(key);
122 attr.value = ptr_to_u64(value);
124 return sys_bpf(BPF_MAP_LOOKUP_ELEM, &attr, sizeof(attr));
127 int bpf_map_delete_elem(int fd, void *key)
131 bzero(&attr, sizeof(attr));
133 attr.key = ptr_to_u64(key);
135 return sys_bpf(BPF_MAP_DELETE_ELEM, &attr, sizeof(attr));
138 int bpf_map_get_next_key(int fd, void *key, void *next_key)
142 bzero(&attr, sizeof(attr));
144 attr.key = ptr_to_u64(key);
145 attr.next_key = ptr_to_u64(next_key);
147 return sys_bpf(BPF_MAP_GET_NEXT_KEY, &attr, sizeof(attr));
150 int bpf_obj_pin(int fd, const char *pathname)
154 bzero(&attr, sizeof(attr));
155 attr.pathname = ptr_to_u64((void *)pathname);
158 return sys_bpf(BPF_OBJ_PIN, &attr, sizeof(attr));
161 int bpf_obj_get(const char *pathname)
165 bzero(&attr, sizeof(attr));
166 attr.pathname = ptr_to_u64((void *)pathname);
168 return sys_bpf(BPF_OBJ_GET, &attr, sizeof(attr));
171 int bpf_prog_attach(int prog_fd, int target_fd, enum bpf_attach_type type,
176 bzero(&attr, sizeof(attr));
177 attr.target_fd = target_fd;
178 attr.attach_bpf_fd = prog_fd;
179 attr.attach_type = type;
180 attr.attach_flags = flags;
182 return sys_bpf(BPF_PROG_ATTACH, &attr, sizeof(attr));
185 int bpf_prog_detach(int target_fd, enum bpf_attach_type type)
189 bzero(&attr, sizeof(attr));
190 attr.target_fd = target_fd;
191 attr.attach_type = type;
193 return sys_bpf(BPF_PROG_DETACH, &attr, sizeof(attr));