linux/tools/lib/bpf/bpf.h
Roberto Sassu 97c8f9dd5d libbpf: Introduce bpf_link_get_fd_by_id_opts()
Introduce bpf_link_get_fd_by_id_opts(), for symmetry with
bpf_map_get_fd_by_id_opts(), to let the caller pass the newly introduced
data structure bpf_get_fd_by_id_opts. Keep the existing
bpf_link_get_fd_by_id(), and call bpf_link_get_fd_by_id_opts() with NULL as
opts argument, to prevent setting open_flags.

Currently, the kernel does not support non-zero open_flags for
bpf_link_get_fd_by_id_opts(), and a call with them will result in an error
returned by the bpf() system call. The caller should always pass zero
open_flags.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221006110736.84253-6-roberto.sassu@huaweicloud.com
2022-10-10 16:49:20 -07:00

455 lines
16 KiB
C

/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
/*
* common eBPF ELF operations.
*
* Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
* Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
* Copyright (C) 2015 Huawei Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation;
* version 2.1 of the License (not later!)
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this program; if not, see <http://www.gnu.org/licenses>
*/
#ifndef __LIBBPF_BPF_H
#define __LIBBPF_BPF_H
#include <linux/bpf.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include "libbpf_common.h"
#include "libbpf_legacy.h"
#ifdef __cplusplus
extern "C" {
#endif
int libbpf_set_memlock_rlim(size_t memlock_bytes);
struct bpf_map_create_opts {
size_t sz; /* size of this struct for forward/backward compatibility */
__u32 btf_fd;
__u32 btf_key_type_id;
__u32 btf_value_type_id;
__u32 btf_vmlinux_value_type_id;
__u32 inner_map_fd;
__u32 map_flags;
__u64 map_extra;
__u32 numa_node;
__u32 map_ifindex;
};
#define bpf_map_create_opts__last_field map_ifindex
LIBBPF_API int bpf_map_create(enum bpf_map_type map_type,
const char *map_name,
__u32 key_size,
__u32 value_size,
__u32 max_entries,
const struct bpf_map_create_opts *opts);
struct bpf_prog_load_opts {
size_t sz; /* size of this struct for forward/backward compatibility */
/* libbpf can retry BPF_PROG_LOAD command if bpf() syscall returns
* -EAGAIN. This field determines how many attempts libbpf has to
* make. If not specified, libbpf will use default value of 5.
*/
int attempts;
enum bpf_attach_type expected_attach_type;
__u32 prog_btf_fd;
__u32 prog_flags;
__u32 prog_ifindex;
__u32 kern_version;
__u32 attach_btf_id;
__u32 attach_prog_fd;
__u32 attach_btf_obj_fd;
const int *fd_array;
/* .BTF.ext func info data */
const void *func_info;
__u32 func_info_cnt;
__u32 func_info_rec_size;
/* .BTF.ext line info data */
const void *line_info;
__u32 line_info_cnt;
__u32 line_info_rec_size;
/* verifier log options */
__u32 log_level;
__u32 log_size;
char *log_buf;
};
#define bpf_prog_load_opts__last_field log_buf
LIBBPF_API int bpf_prog_load(enum bpf_prog_type prog_type,
const char *prog_name, const char *license,
const struct bpf_insn *insns, size_t insn_cnt,
const struct bpf_prog_load_opts *opts);
/* Flags to direct loading requirements */
#define MAPS_RELAX_COMPAT 0x01
/* Recommended log buffer size */
#define BPF_LOG_BUF_SIZE (UINT32_MAX >> 8) /* verifier maximum in kernels <= 5.1 */
struct bpf_btf_load_opts {
size_t sz; /* size of this struct for forward/backward compatibility */
/* kernel log options */
char *log_buf;
__u32 log_level;
__u32 log_size;
};
#define bpf_btf_load_opts__last_field log_size
LIBBPF_API int bpf_btf_load(const void *btf_data, size_t btf_size,
const struct bpf_btf_load_opts *opts);
LIBBPF_API int bpf_map_update_elem(int fd, const void *key, const void *value,
__u64 flags);
LIBBPF_API int bpf_map_lookup_elem(int fd, const void *key, void *value);
LIBBPF_API int bpf_map_lookup_elem_flags(int fd, const void *key, void *value,
__u64 flags);
LIBBPF_API int bpf_map_lookup_and_delete_elem(int fd, const void *key,
void *value);
LIBBPF_API int bpf_map_lookup_and_delete_elem_flags(int fd, const void *key,
void *value, __u64 flags);
LIBBPF_API int bpf_map_delete_elem(int fd, const void *key);
LIBBPF_API int bpf_map_delete_elem_flags(int fd, const void *key, __u64 flags);
LIBBPF_API int bpf_map_get_next_key(int fd, const void *key, void *next_key);
LIBBPF_API int bpf_map_freeze(int fd);
struct bpf_map_batch_opts {
size_t sz; /* size of this struct for forward/backward compatibility */
__u64 elem_flags;
__u64 flags;
};
#define bpf_map_batch_opts__last_field flags
/**
* @brief **bpf_map_delete_batch()** allows for batch deletion of multiple
* elements in a BPF map.
*
* @param fd BPF map file descriptor
* @param keys pointer to an array of *count* keys
* @param count input and output parameter; on input **count** represents the
* number of elements in the map to delete in batch;
* on output if a non-EFAULT error is returned, **count** represents the number of deleted
* elements if the output **count** value is not equal to the input **count** value
* If EFAULT is returned, **count** should not be trusted to be correct.
* @param opts options for configuring the way the batch deletion works
* @return 0, on success; negative error code, otherwise (errno is also set to
* the error code)
*/
LIBBPF_API int bpf_map_delete_batch(int fd, const void *keys,
__u32 *count,
const struct bpf_map_batch_opts *opts);
/**
* @brief **bpf_map_lookup_batch()** allows for batch lookup of BPF map elements.
*
* The parameter *in_batch* is the address of the first element in the batch to read.
* *out_batch* is an output parameter that should be passed as *in_batch* to subsequent
* calls to **bpf_map_lookup_batch()**. NULL can be passed for *in_batch* to indicate
* that the batched lookup starts from the beginning of the map.
*
* The *keys* and *values* are output parameters which must point to memory large enough to
* hold *count* items based on the key and value size of the map *map_fd*. The *keys*
* buffer must be of *key_size* * *count*. The *values* buffer must be of
* *value_size* * *count*.
*
* @param fd BPF map file descriptor
* @param in_batch address of the first element in batch to read, can pass NULL to
* indicate that the batched lookup starts from the beginning of the map.
* @param out_batch output parameter that should be passed to next call as *in_batch*
* @param keys pointer to an array large enough for *count* keys
* @param values pointer to an array large enough for *count* values
* @param count input and output parameter; on input it's the number of elements
* in the map to read in batch; on output it's the number of elements that were
* successfully read.
* If a non-EFAULT error is returned, count will be set as the number of elements
* that were read before the error occurred.
* If EFAULT is returned, **count** should not be trusted to be correct.
* @param opts options for configuring the way the batch lookup works
* @return 0, on success; negative error code, otherwise (errno is also set to
* the error code)
*/
LIBBPF_API int bpf_map_lookup_batch(int fd, void *in_batch, void *out_batch,
void *keys, void *values, __u32 *count,
const struct bpf_map_batch_opts *opts);
/**
* @brief **bpf_map_lookup_and_delete_batch()** allows for batch lookup and deletion
* of BPF map elements where each element is deleted after being retrieved.
*
* @param fd BPF map file descriptor
* @param in_batch address of the first element in batch to read, can pass NULL to
* get address of the first element in *out_batch*
* @param out_batch output parameter that should be passed to next call as *in_batch*
* @param keys pointer to an array of *count* keys
* @param values pointer to an array large enough for *count* values
* @param count input and output parameter; on input it's the number of elements
* in the map to read and delete in batch; on output it represents the number of
* elements that were successfully read and deleted
* If a non-**EFAULT** error code is returned and if the output **count** value
* is not equal to the input **count** value, up to **count** elements may
* have been deleted.
* if **EFAULT** is returned up to *count* elements may have been deleted without
* being returned via the *keys* and *values* output parameters.
* @param opts options for configuring the way the batch lookup and delete works
* @return 0, on success; negative error code, otherwise (errno is also set to
* the error code)
*/
LIBBPF_API int bpf_map_lookup_and_delete_batch(int fd, void *in_batch,
void *out_batch, void *keys,
void *values, __u32 *count,
const struct bpf_map_batch_opts *opts);
/**
* @brief **bpf_map_update_batch()** updates multiple elements in a map
* by specifying keys and their corresponding values.
*
* The *keys* and *values* parameters must point to memory large enough
* to hold *count* items based on the key and value size of the map.
*
* The *opts* parameter can be used to control how *bpf_map_update_batch()*
* should handle keys that either do or do not already exist in the map.
* In particular the *flags* parameter of *bpf_map_batch_opts* can be
* one of the following:
*
* Note that *count* is an input and output parameter, where on output it
* represents how many elements were successfully updated. Also note that if
* **EFAULT** then *count* should not be trusted to be correct.
*
* **BPF_ANY**
* Create new elements or update existing.
*
* **BPF_NOEXIST**
* Create new elements only if they do not exist.
*
* **BPF_EXIST**
* Update existing elements.
*
* **BPF_F_LOCK**
* Update spin_lock-ed map elements. This must be
* specified if the map value contains a spinlock.
*
* @param fd BPF map file descriptor
* @param keys pointer to an array of *count* keys
* @param values pointer to an array of *count* values
* @param count input and output parameter; on input it's the number of elements
* in the map to update in batch; on output if a non-EFAULT error is returned,
* **count** represents the number of updated elements if the output **count**
* value is not equal to the input **count** value.
* If EFAULT is returned, **count** should not be trusted to be correct.
* @param opts options for configuring the way the batch update works
* @return 0, on success; negative error code, otherwise (errno is also set to
* the error code)
*/
LIBBPF_API int bpf_map_update_batch(int fd, const void *keys, const void *values,
__u32 *count,
const struct bpf_map_batch_opts *opts);
struct bpf_obj_get_opts {
size_t sz; /* size of this struct for forward/backward compatibility */
__u32 file_flags;
size_t :0;
};
#define bpf_obj_get_opts__last_field file_flags
LIBBPF_API int bpf_obj_pin(int fd, const char *pathname);
LIBBPF_API int bpf_obj_get(const char *pathname);
LIBBPF_API int bpf_obj_get_opts(const char *pathname,
const struct bpf_obj_get_opts *opts);
struct bpf_prog_attach_opts {
size_t sz; /* size of this struct for forward/backward compatibility */
unsigned int flags;
int replace_prog_fd;
};
#define bpf_prog_attach_opts__last_field replace_prog_fd
LIBBPF_API int bpf_prog_attach(int prog_fd, int attachable_fd,
enum bpf_attach_type type, unsigned int flags);
LIBBPF_API int bpf_prog_attach_opts(int prog_fd, int attachable_fd,
enum bpf_attach_type type,
const struct bpf_prog_attach_opts *opts);
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;
__u32 target_btf_id;
union {
struct {
__u64 bpf_cookie;
} perf_event;
struct {
__u32 flags;
__u32 cnt;
const char **syms;
const unsigned long *addrs;
const __u64 *cookies;
} kprobe_multi;
struct {
__u64 cookie;
} tracing;
};
size_t :0;
};
#define bpf_link_create_opts__last_field kprobe_multi.cookies
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 */
__u32 old_prog_fd; /* expected old program FD */
};
#define bpf_link_update_opts__last_field old_prog_fd
LIBBPF_API int bpf_link_update(int link_fd, int new_prog_fd,
const struct bpf_link_update_opts *opts);
LIBBPF_API int bpf_iter_create(int link_fd);
struct bpf_prog_test_run_attr {
int prog_fd;
int repeat;
const void *data_in;
__u32 data_size_in;
void *data_out; /* optional */
__u32 data_size_out; /* in: max length of data_out
* out: length of data_out */
__u32 retval; /* out: return code of the BPF program */
__u32 duration; /* out: average per repetition in ns */
const void *ctx_in; /* optional */
__u32 ctx_size_in;
void *ctx_out; /* optional */
__u32 ctx_size_out; /* in: max length of ctx_out
* out: length of cxt_out */
};
LIBBPF_API int bpf_prog_get_next_id(__u32 start_id, __u32 *next_id);
LIBBPF_API int bpf_map_get_next_id(__u32 start_id, __u32 *next_id);
LIBBPF_API int bpf_btf_get_next_id(__u32 start_id, __u32 *next_id);
LIBBPF_API int bpf_link_get_next_id(__u32 start_id, __u32 *next_id);
struct bpf_get_fd_by_id_opts {
size_t sz; /* size of this struct for forward/backward compatibility */
__u32 open_flags; /* permissions requested for the operation on fd */
size_t :0;
};
#define bpf_get_fd_by_id_opts__last_field open_flags
LIBBPF_API int bpf_prog_get_fd_by_id(__u32 id);
LIBBPF_API int bpf_prog_get_fd_by_id_opts(__u32 id,
const struct bpf_get_fd_by_id_opts *opts);
LIBBPF_API int bpf_map_get_fd_by_id(__u32 id);
LIBBPF_API int bpf_map_get_fd_by_id_opts(__u32 id,
const struct bpf_get_fd_by_id_opts *opts);
LIBBPF_API int bpf_btf_get_fd_by_id(__u32 id);
LIBBPF_API int bpf_btf_get_fd_by_id_opts(__u32 id,
const struct bpf_get_fd_by_id_opts *opts);
LIBBPF_API int bpf_link_get_fd_by_id(__u32 id);
LIBBPF_API int bpf_link_get_fd_by_id_opts(__u32 id,
const struct bpf_get_fd_by_id_opts *opts);
LIBBPF_API int bpf_obj_get_info_by_fd(int bpf_fd, void *info, __u32 *info_len);
struct bpf_prog_query_opts {
size_t sz; /* size of this struct for forward/backward compatibility */
__u32 query_flags;
__u32 attach_flags; /* output argument */
__u32 *prog_ids;
__u32 prog_cnt; /* input+output argument */
__u32 *prog_attach_flags;
};
#define bpf_prog_query_opts__last_field prog_attach_flags
LIBBPF_API int bpf_prog_query_opts(int target_fd,
enum bpf_attach_type type,
struct bpf_prog_query_opts *opts);
LIBBPF_API int bpf_prog_query(int target_fd, enum bpf_attach_type type,
__u32 query_flags, __u32 *attach_flags,
__u32 *prog_ids, __u32 *prog_cnt);
LIBBPF_API int bpf_raw_tracepoint_open(const char *name, int prog_fd);
LIBBPF_API int bpf_task_fd_query(int pid, int fd, __u32 flags, char *buf,
__u32 *buf_len, __u32 *prog_id, __u32 *fd_type,
__u64 *probe_offset, __u64 *probe_addr);
enum bpf_stats_type; /* defined in up-to-date linux/bpf.h */
LIBBPF_API int bpf_enable_stats(enum bpf_stats_type type);
struct bpf_prog_bind_opts {
size_t sz; /* size of this struct for forward/backward compatibility */
__u32 flags;
};
#define bpf_prog_bind_opts__last_field flags
LIBBPF_API int bpf_prog_bind_map(int prog_fd, int map_fd,
const struct bpf_prog_bind_opts *opts);
struct bpf_test_run_opts {
size_t sz; /* size of this struct for forward/backward compatibility */
const void *data_in; /* optional */
void *data_out; /* optional */
__u32 data_size_in;
__u32 data_size_out; /* in: max length of data_out
* out: length of data_out
*/
const void *ctx_in; /* optional */
void *ctx_out; /* optional */
__u32 ctx_size_in;
__u32 ctx_size_out; /* in: max length of ctx_out
* out: length of cxt_out
*/
__u32 retval; /* out: return code of the BPF program */
int repeat;
__u32 duration; /* out: average per repetition in ns */
__u32 flags;
__u32 cpu;
__u32 batch_size;
};
#define bpf_test_run_opts__last_field batch_size
LIBBPF_API int bpf_prog_test_run_opts(int prog_fd,
struct bpf_test_run_opts *opts);
#ifdef __cplusplus
} /* extern "C" */
#endif
#endif /* __LIBBPF_BPF_H */