1917 lines
		
	
	
		
			73 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			1917 lines
		
	
	
		
			73 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
 | |
| 
 | |
| /*
 | |
|  * Common eBPF ELF object loading operations.
 | |
|  *
 | |
|  * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
 | |
|  * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
 | |
|  * Copyright (C) 2015 Huawei Inc.
 | |
|  */
 | |
| #ifndef __LIBBPF_LIBBPF_H
 | |
| #define __LIBBPF_LIBBPF_H
 | |
| 
 | |
| #include <stdarg.h>
 | |
| #include <stdio.h>
 | |
| #include <stdint.h>
 | |
| #include <stdbool.h>
 | |
| #include <sys/types.h>  // for size_t
 | |
| #include <linux/bpf.h>
 | |
| 
 | |
| #include "libbpf_common.h"
 | |
| #include "libbpf_legacy.h"
 | |
| 
 | |
| #ifdef __cplusplus
 | |
| extern "C" {
 | |
| #endif
 | |
| 
 | |
| LIBBPF_API __u32 libbpf_major_version(void);
 | |
| LIBBPF_API __u32 libbpf_minor_version(void);
 | |
| LIBBPF_API const char *libbpf_version_string(void);
 | |
| 
 | |
| enum libbpf_errno {
 | |
| 	__LIBBPF_ERRNO__START = 4000,
 | |
| 
 | |
| 	/* Something wrong in libelf */
 | |
| 	LIBBPF_ERRNO__LIBELF = __LIBBPF_ERRNO__START,
 | |
| 	LIBBPF_ERRNO__FORMAT,	/* BPF object format invalid */
 | |
| 	LIBBPF_ERRNO__KVERSION,	/* Incorrect or no 'version' section */
 | |
| 	LIBBPF_ERRNO__ENDIAN,	/* Endian mismatch */
 | |
| 	LIBBPF_ERRNO__INTERNAL,	/* Internal error in libbpf */
 | |
| 	LIBBPF_ERRNO__RELOC,	/* Relocation failed */
 | |
| 	LIBBPF_ERRNO__LOAD,	/* Load program failure for unknown reason */
 | |
| 	LIBBPF_ERRNO__VERIFY,	/* Kernel verifier blocks program loading */
 | |
| 	LIBBPF_ERRNO__PROG2BIG,	/* Program too big */
 | |
| 	LIBBPF_ERRNO__KVER,	/* Incorrect kernel version */
 | |
| 	LIBBPF_ERRNO__PROGTYPE,	/* Kernel doesn't support this program type */
 | |
| 	LIBBPF_ERRNO__WRNGPID,	/* Wrong pid in netlink message */
 | |
| 	LIBBPF_ERRNO__INVSEQ,	/* Invalid netlink sequence */
 | |
| 	LIBBPF_ERRNO__NLPARSE,	/* netlink parsing error */
 | |
| 	__LIBBPF_ERRNO__END,
 | |
| };
 | |
| 
 | |
| LIBBPF_API int libbpf_strerror(int err, char *buf, size_t size);
 | |
| 
 | |
| /**
 | |
|  * @brief **libbpf_bpf_attach_type_str()** converts the provided attach type
 | |
|  * value into a textual representation.
 | |
|  * @param t The attach type.
 | |
|  * @return Pointer to a static string identifying the attach type. NULL is
 | |
|  * returned for unknown **bpf_attach_type** values.
 | |
|  */
 | |
| LIBBPF_API const char *libbpf_bpf_attach_type_str(enum bpf_attach_type t);
 | |
| 
 | |
| /**
 | |
|  * @brief **libbpf_bpf_link_type_str()** converts the provided link type value
 | |
|  * into a textual representation.
 | |
|  * @param t The link type.
 | |
|  * @return Pointer to a static string identifying the link type. NULL is
 | |
|  * returned for unknown **bpf_link_type** values.
 | |
|  */
 | |
| LIBBPF_API const char *libbpf_bpf_link_type_str(enum bpf_link_type t);
 | |
| 
 | |
| /**
 | |
|  * @brief **libbpf_bpf_map_type_str()** converts the provided map type value
 | |
|  * into a textual representation.
 | |
|  * @param t The map type.
 | |
|  * @return Pointer to a static string identifying the map type. NULL is
 | |
|  * returned for unknown **bpf_map_type** values.
 | |
|  */
 | |
| LIBBPF_API const char *libbpf_bpf_map_type_str(enum bpf_map_type t);
 | |
| 
 | |
| /**
 | |
|  * @brief **libbpf_bpf_prog_type_str()** converts the provided program type
 | |
|  * value into a textual representation.
 | |
|  * @param t The program type.
 | |
|  * @return Pointer to a static string identifying the program type. NULL is
 | |
|  * returned for unknown **bpf_prog_type** values.
 | |
|  */
 | |
| LIBBPF_API const char *libbpf_bpf_prog_type_str(enum bpf_prog_type t);
 | |
| 
 | |
| enum libbpf_print_level {
 | |
|         LIBBPF_WARN,
 | |
|         LIBBPF_INFO,
 | |
|         LIBBPF_DEBUG,
 | |
| };
 | |
| 
 | |
| typedef int (*libbpf_print_fn_t)(enum libbpf_print_level level,
 | |
| 				 const char *, va_list ap);
 | |
| 
 | |
| /**
 | |
|  * @brief **libbpf_set_print()** sets user-provided log callback function to
 | |
|  * be used for libbpf warnings and informational messages. If the user callback
 | |
|  * is not set, messages are logged to stderr by default. The verbosity of these
 | |
|  * messages can be controlled by setting the environment variable
 | |
|  * LIBBPF_LOG_LEVEL to either warn, info, or debug.
 | |
|  * @param fn The log print function. If NULL, libbpf won't print anything.
 | |
|  * @return Pointer to old print function.
 | |
|  *
 | |
|  * This function is thread-safe.
 | |
|  */
 | |
| LIBBPF_API libbpf_print_fn_t libbpf_set_print(libbpf_print_fn_t fn);
 | |
| 
 | |
| /* Hide internal to user */
 | |
| struct bpf_object;
 | |
| 
 | |
| struct bpf_object_open_opts {
 | |
| 	/* size of this struct, for forward/backward compatibility */
 | |
| 	size_t sz;
 | |
| 	/* object name override, if provided:
 | |
| 	 * - for object open from file, this will override setting object
 | |
| 	 *   name from file path's base name;
 | |
| 	 * - for object open from memory buffer, this will specify an object
 | |
| 	 *   name and will override default "<addr>-<buf-size>" name;
 | |
| 	 */
 | |
| 	const char *object_name;
 | |
| 	/* parse map definitions non-strictly, allowing extra attributes/data */
 | |
| 	bool relaxed_maps;
 | |
| 	/* maps that set the 'pinning' attribute in their definition will have
 | |
| 	 * their pin_path attribute set to a file in this directory, and be
 | |
| 	 * auto-pinned to that path on load; defaults to "/sys/fs/bpf".
 | |
| 	 */
 | |
| 	const char *pin_root_path;
 | |
| 
 | |
| 	__u32 :32; /* stub out now removed attach_prog_fd */
 | |
| 
 | |
| 	/* Additional kernel config content that augments and overrides
 | |
| 	 * system Kconfig for CONFIG_xxx externs.
 | |
| 	 */
 | |
| 	const char *kconfig;
 | |
| 	/* Path to the custom BTF to be used for BPF CO-RE relocations.
 | |
| 	 * This custom BTF completely replaces the use of vmlinux BTF
 | |
| 	 * for the purpose of CO-RE relocations.
 | |
| 	 * NOTE: any other BPF feature (e.g., fentry/fexit programs,
 | |
| 	 * struct_ops, etc) will need actual kernel BTF at /sys/kernel/btf/vmlinux.
 | |
| 	 */
 | |
| 	const char *btf_custom_path;
 | |
| 	/* Pointer to a buffer for storing kernel logs for applicable BPF
 | |
| 	 * commands. Valid kernel_log_size has to be specified as well and are
 | |
| 	 * passed-through to bpf() syscall. Keep in mind that kernel might
 | |
| 	 * fail operation with -ENOSPC error if provided buffer is too small
 | |
| 	 * to contain entire log output.
 | |
| 	 * See the comment below for kernel_log_level for interaction between
 | |
| 	 * log_buf and log_level settings.
 | |
| 	 *
 | |
| 	 * If specified, this log buffer will be passed for:
 | |
| 	 *   - each BPF progral load (BPF_PROG_LOAD) attempt, unless overridden
 | |
| 	 *     with bpf_program__set_log() on per-program level, to get
 | |
| 	 *     BPF verifier log output.
 | |
| 	 *   - during BPF object's BTF load into kernel (BPF_BTF_LOAD) to get
 | |
| 	 *     BTF sanity checking log.
 | |
| 	 *
 | |
| 	 * Each BPF command (BPF_BTF_LOAD or BPF_PROG_LOAD) will overwrite
 | |
| 	 * previous contents, so if you need more fine-grained control, set
 | |
| 	 * per-program buffer with bpf_program__set_log_buf() to preserve each
 | |
| 	 * individual program's verification log. Keep using kernel_log_buf
 | |
| 	 * for BTF verification log, if necessary.
 | |
| 	 */
 | |
| 	char *kernel_log_buf;
 | |
| 	size_t kernel_log_size;
 | |
| 	/*
 | |
| 	 * Log level can be set independently from log buffer. Log_level=0
 | |
| 	 * means that libbpf will attempt loading BTF or program without any
 | |
| 	 * logging requested, but will retry with either its own or custom log
 | |
| 	 * buffer, if provided, and log_level=1 on any error.
 | |
| 	 * And vice versa, setting log_level>0 will request BTF or prog
 | |
| 	 * loading with verbose log from the first attempt (and as such also
 | |
| 	 * for successfully loaded BTF or program), and the actual log buffer
 | |
| 	 * could be either libbpf's own auto-allocated log buffer, if
 | |
| 	 * kernel_log_buffer is NULL, or user-provided custom kernel_log_buf.
 | |
| 	 * If user didn't provide custom log buffer, libbpf will emit captured
 | |
| 	 * logs through its print callback.
 | |
| 	 */
 | |
| 	__u32 kernel_log_level;
 | |
| 	/* Path to BPF FS mount point to derive BPF token from.
 | |
| 	 *
 | |
| 	 * Created BPF token will be used for all bpf() syscall operations
 | |
| 	 * that accept BPF token (e.g., map creation, BTF and program loads,
 | |
| 	 * etc) automatically within instantiated BPF object.
 | |
| 	 *
 | |
| 	 * If bpf_token_path is not specified, libbpf will consult
 | |
| 	 * LIBBPF_BPF_TOKEN_PATH environment variable. If set, it will be
 | |
| 	 * taken as a value of bpf_token_path option and will force libbpf to
 | |
| 	 * either create BPF token from provided custom BPF FS path, or will
 | |
| 	 * disable implicit BPF token creation, if envvar value is an empty
 | |
| 	 * string. bpf_token_path overrides LIBBPF_BPF_TOKEN_PATH, if both are
 | |
| 	 * set at the same time.
 | |
| 	 *
 | |
| 	 * Setting bpf_token_path option to empty string disables libbpf's
 | |
| 	 * automatic attempt to create BPF token from default BPF FS mount
 | |
| 	 * point (/sys/fs/bpf), in case this default behavior is undesirable.
 | |
| 	 */
 | |
| 	const char *bpf_token_path;
 | |
| 
 | |
| 	size_t :0;
 | |
| };
 | |
| #define bpf_object_open_opts__last_field bpf_token_path
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_object__open()** creates a bpf_object by opening
 | |
|  * the BPF ELF object file pointed to by the passed path and loading it
 | |
|  * into memory.
 | |
|  * @param path BPF object file path.
 | |
|  * @return pointer to the new bpf_object; or NULL is returned on error,
 | |
|  * error code is stored in errno
 | |
|  */
 | |
| LIBBPF_API struct bpf_object *bpf_object__open(const char *path);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_object__open_file()** creates a bpf_object by opening
 | |
|  * the BPF ELF object file pointed to by the passed path and loading it
 | |
|  * into memory.
 | |
|  * @param path BPF object file path
 | |
|  * @param opts options for how to load the bpf object, this parameter is
 | |
|  * optional and can be set to NULL
 | |
|  * @return pointer to the new bpf_object; or NULL is returned on error,
 | |
|  * error code is stored in errno
 | |
|  */
 | |
| LIBBPF_API struct bpf_object *
 | |
| bpf_object__open_file(const char *path, const struct bpf_object_open_opts *opts);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_object__open_mem()** creates a bpf_object by reading
 | |
|  * the BPF objects raw bytes from a memory buffer containing a valid
 | |
|  * BPF ELF object file.
 | |
|  * @param obj_buf pointer to the buffer containing ELF file bytes
 | |
|  * @param obj_buf_sz number of bytes in the buffer
 | |
|  * @param opts options for how to load the bpf object
 | |
|  * @return pointer to the new bpf_object; or NULL is returned on error,
 | |
|  * error code is stored in errno
 | |
|  */
 | |
| LIBBPF_API struct bpf_object *
 | |
| bpf_object__open_mem(const void *obj_buf, size_t obj_buf_sz,
 | |
| 		     const struct bpf_object_open_opts *opts);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_object__load()** loads BPF object into kernel.
 | |
|  * @param obj Pointer to a valid BPF object instance returned by
 | |
|  * **bpf_object__open*()** APIs
 | |
|  * @return 0, on success; negative error code, otherwise, error code is
 | |
|  * stored in errno
 | |
|  */
 | |
| LIBBPF_API int bpf_object__load(struct bpf_object *obj);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_object__close()** closes a BPF object and releases all
 | |
|  * resources.
 | |
|  * @param obj Pointer to a valid BPF object
 | |
|  */
 | |
| LIBBPF_API void bpf_object__close(struct bpf_object *obj);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_object__pin_maps()** pins each map contained within
 | |
|  * the BPF object at the passed directory.
 | |
|  * @param obj Pointer to a valid BPF object
 | |
|  * @param path A directory where maps should be pinned.
 | |
|  * @return 0, on success; negative error code, otherwise
 | |
|  *
 | |
|  * If `path` is NULL `bpf_map__pin` (which is being used on each map)
 | |
|  * will use the pin_path attribute of each map. In this case, maps that
 | |
|  * don't have a pin_path set will be ignored.
 | |
|  */
 | |
| LIBBPF_API int bpf_object__pin_maps(struct bpf_object *obj, const char *path);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_object__unpin_maps()** unpins each map contained within
 | |
|  * the BPF object found in the passed directory.
 | |
|  * @param obj Pointer to a valid BPF object
 | |
|  * @param path A directory where pinned maps should be searched for.
 | |
|  * @return 0, on success; negative error code, otherwise
 | |
|  *
 | |
|  * If `path` is NULL `bpf_map__unpin` (which is being used on each map)
 | |
|  * will use the pin_path attribute of each map. In this case, maps that
 | |
|  * don't have a pin_path set will be ignored.
 | |
|  */
 | |
| LIBBPF_API int bpf_object__unpin_maps(struct bpf_object *obj,
 | |
| 				      const char *path);
 | |
| LIBBPF_API int bpf_object__pin_programs(struct bpf_object *obj,
 | |
| 					const char *path);
 | |
| LIBBPF_API int bpf_object__unpin_programs(struct bpf_object *obj,
 | |
| 					  const char *path);
 | |
| LIBBPF_API int bpf_object__pin(struct bpf_object *object, const char *path);
 | |
| LIBBPF_API int bpf_object__unpin(struct bpf_object *object, const char *path);
 | |
| 
 | |
| LIBBPF_API const char *bpf_object__name(const struct bpf_object *obj);
 | |
| LIBBPF_API unsigned int bpf_object__kversion(const struct bpf_object *obj);
 | |
| LIBBPF_API int bpf_object__set_kversion(struct bpf_object *obj, __u32 kern_version);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_object__token_fd** is an accessor for BPF token FD associated
 | |
|  * with BPF object.
 | |
|  * @param obj Pointer to a valid BPF object
 | |
|  * @return BPF token FD or -1, if it wasn't set
 | |
|  */
 | |
| LIBBPF_API int bpf_object__token_fd(const struct bpf_object *obj);
 | |
| 
 | |
| struct btf;
 | |
| LIBBPF_API struct btf *bpf_object__btf(const struct bpf_object *obj);
 | |
| LIBBPF_API int bpf_object__btf_fd(const struct bpf_object *obj);
 | |
| 
 | |
| LIBBPF_API struct bpf_program *
 | |
| bpf_object__find_program_by_name(const struct bpf_object *obj,
 | |
| 				 const char *name);
 | |
| 
 | |
| LIBBPF_API int
 | |
| libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
 | |
| 			 enum bpf_attach_type *expected_attach_type);
 | |
| LIBBPF_API int libbpf_attach_type_by_name(const char *name,
 | |
| 					  enum bpf_attach_type *attach_type);
 | |
| LIBBPF_API int libbpf_find_vmlinux_btf_id(const char *name,
 | |
| 					  enum bpf_attach_type attach_type);
 | |
| 
 | |
| /* Accessors of bpf_program */
 | |
| struct bpf_program;
 | |
| 
 | |
| LIBBPF_API struct bpf_program *
 | |
| bpf_object__next_program(const struct bpf_object *obj, struct bpf_program *prog);
 | |
| 
 | |
| #define bpf_object__for_each_program(pos, obj)			\
 | |
| 	for ((pos) = bpf_object__next_program((obj), NULL);	\
 | |
| 	     (pos) != NULL;					\
 | |
| 	     (pos) = bpf_object__next_program((obj), (pos)))
 | |
| 
 | |
| LIBBPF_API struct bpf_program *
 | |
| bpf_object__prev_program(const struct bpf_object *obj, struct bpf_program *prog);
 | |
| 
 | |
| LIBBPF_API void bpf_program__set_ifindex(struct bpf_program *prog,
 | |
| 					 __u32 ifindex);
 | |
| 
 | |
| LIBBPF_API const char *bpf_program__name(const struct bpf_program *prog);
 | |
| LIBBPF_API const char *bpf_program__section_name(const struct bpf_program *prog);
 | |
| LIBBPF_API bool bpf_program__autoload(const struct bpf_program *prog);
 | |
| LIBBPF_API int bpf_program__set_autoload(struct bpf_program *prog, bool autoload);
 | |
| LIBBPF_API bool bpf_program__autoattach(const struct bpf_program *prog);
 | |
| LIBBPF_API void bpf_program__set_autoattach(struct bpf_program *prog, bool autoattach);
 | |
| 
 | |
| struct bpf_insn;
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_program__insns()** gives read-only access to BPF program's
 | |
|  * underlying BPF instructions.
 | |
|  * @param prog BPF program for which to return instructions
 | |
|  * @return a pointer to an array of BPF instructions that belong to the
 | |
|  * specified BPF program
 | |
|  *
 | |
|  * Returned pointer is always valid and not NULL. Number of `struct bpf_insn`
 | |
|  * pointed to can be fetched using **bpf_program__insn_cnt()** API.
 | |
|  *
 | |
|  * Keep in mind, libbpf can modify and append/delete BPF program's
 | |
|  * instructions as it processes BPF object file and prepares everything for
 | |
|  * uploading into the kernel. So depending on the point in BPF object
 | |
|  * lifetime, **bpf_program__insns()** can return different sets of
 | |
|  * instructions. As an example, during BPF object load phase BPF program
 | |
|  * instructions will be CO-RE-relocated, BPF subprograms instructions will be
 | |
|  * appended, ldimm64 instructions will have FDs embedded, etc. So instructions
 | |
|  * returned before **bpf_object__load()** and after it might be quite
 | |
|  * different.
 | |
|  */
 | |
| LIBBPF_API const struct bpf_insn *bpf_program__insns(const struct bpf_program *prog);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_program__set_insns()** can set BPF program's underlying
 | |
|  * BPF instructions.
 | |
|  *
 | |
|  * WARNING: This is a very advanced libbpf API and users need to know
 | |
|  * what they are doing. This should be used from prog_prepare_load_fn
 | |
|  * callback only.
 | |
|  *
 | |
|  * @param prog BPF program for which to return instructions
 | |
|  * @param new_insns a pointer to an array of BPF instructions
 | |
|  * @param new_insn_cnt number of `struct bpf_insn`'s that form
 | |
|  * specified BPF program
 | |
|  * @return 0, on success; negative error code, otherwise
 | |
|  */
 | |
| LIBBPF_API int bpf_program__set_insns(struct bpf_program *prog,
 | |
| 				      struct bpf_insn *new_insns, size_t new_insn_cnt);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_program__insn_cnt()** returns number of `struct bpf_insn`'s
 | |
|  * that form specified BPF program.
 | |
|  * @param prog BPF program for which to return number of BPF instructions
 | |
|  *
 | |
|  * See **bpf_program__insns()** documentation for notes on how libbpf can
 | |
|  * change instructions and their count during different phases of
 | |
|  * **bpf_object** lifetime.
 | |
|  */
 | |
| LIBBPF_API size_t bpf_program__insn_cnt(const struct bpf_program *prog);
 | |
| 
 | |
| LIBBPF_API int bpf_program__fd(const struct bpf_program *prog);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_program__pin()** pins the BPF program to a file
 | |
|  * in the BPF FS specified by a path. This increments the programs
 | |
|  * reference count, allowing it to stay loaded after the process
 | |
|  * which loaded it has exited.
 | |
|  *
 | |
|  * @param prog BPF program to pin, must already be loaded
 | |
|  * @param path file path in a BPF file system
 | |
|  * @return 0, on success; negative error code, otherwise
 | |
|  */
 | |
| LIBBPF_API int bpf_program__pin(struct bpf_program *prog, const char *path);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_program__unpin()** unpins the BPF program from a file
 | |
|  * in the BPFFS specified by a path. This decrements the programs
 | |
|  * reference count.
 | |
|  *
 | |
|  * The file pinning the BPF program can also be unlinked by a different
 | |
|  * process in which case this function will return an error.
 | |
|  *
 | |
|  * @param prog BPF program to unpin
 | |
|  * @param path file path to the pin in a BPF file system
 | |
|  * @return 0, on success; negative error code, otherwise
 | |
|  */
 | |
| LIBBPF_API int bpf_program__unpin(struct bpf_program *prog, const char *path);
 | |
| LIBBPF_API void bpf_program__unload(struct bpf_program *prog);
 | |
| 
 | |
| struct bpf_link;
 | |
| 
 | |
| LIBBPF_API struct bpf_link *bpf_link__open(const char *path);
 | |
| LIBBPF_API int bpf_link__fd(const struct bpf_link *link);
 | |
| LIBBPF_API const char *bpf_link__pin_path(const struct bpf_link *link);
 | |
| /**
 | |
|  * @brief **bpf_link__pin()** pins the BPF link to a file
 | |
|  * in the BPF FS specified by a path. This increments the links
 | |
|  * reference count, allowing it to stay loaded after the process
 | |
|  * which loaded it has exited.
 | |
|  *
 | |
|  * @param link BPF link to pin, must already be loaded
 | |
|  * @param path file path in a BPF file system
 | |
|  * @return 0, on success; negative error code, otherwise
 | |
|  */
 | |
| 
 | |
| LIBBPF_API int bpf_link__pin(struct bpf_link *link, const char *path);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_link__unpin()** unpins the BPF link from a file
 | |
|  * in the BPFFS specified by a path. This decrements the links
 | |
|  * reference count.
 | |
|  *
 | |
|  * The file pinning the BPF link can also be unlinked by a different
 | |
|  * process in which case this function will return an error.
 | |
|  *
 | |
|  * @param prog BPF program to unpin
 | |
|  * @param path file path to the pin in a BPF file system
 | |
|  * @return 0, on success; negative error code, otherwise
 | |
|  */
 | |
| LIBBPF_API int bpf_link__unpin(struct bpf_link *link);
 | |
| LIBBPF_API int bpf_link__update_program(struct bpf_link *link,
 | |
| 					struct bpf_program *prog);
 | |
| LIBBPF_API void bpf_link__disconnect(struct bpf_link *link);
 | |
| LIBBPF_API int bpf_link__detach(struct bpf_link *link);
 | |
| LIBBPF_API int bpf_link__destroy(struct bpf_link *link);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_program__attach()** is a generic function for attaching
 | |
|  * a BPF program based on auto-detection of program type, attach type,
 | |
|  * and extra parameters, where applicable.
 | |
|  *
 | |
|  * @param prog BPF program to attach
 | |
|  * @return Reference to the newly created BPF link; or NULL is returned on error,
 | |
|  * error code is stored in errno
 | |
|  *
 | |
|  * This is supported for:
 | |
|  *   - kprobe/kretprobe (depends on SEC() definition)
 | |
|  *   - uprobe/uretprobe (depends on SEC() definition)
 | |
|  *   - tracepoint
 | |
|  *   - raw tracepoint
 | |
|  *   - tracing programs (typed raw TP/fentry/fexit/fmod_ret)
 | |
|  */
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach(const struct bpf_program *prog);
 | |
| 
 | |
| struct bpf_perf_event_opts {
 | |
| 	/* size of this struct, for forward/backward compatibility */
 | |
| 	size_t sz;
 | |
| 	/* custom user-provided value fetchable through bpf_get_attach_cookie() */
 | |
| 	__u64 bpf_cookie;
 | |
| 	/* don't use BPF link when attach BPF program */
 | |
| 	bool force_ioctl_attach;
 | |
| 	size_t :0;
 | |
| };
 | |
| #define bpf_perf_event_opts__last_field force_ioctl_attach
 | |
| 
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_perf_event(const struct bpf_program *prog, int pfd);
 | |
| 
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_perf_event_opts(const struct bpf_program *prog, int pfd,
 | |
| 				    const struct bpf_perf_event_opts *opts);
 | |
| 
 | |
| /**
 | |
|  * enum probe_attach_mode - the mode to attach kprobe/uprobe
 | |
|  *
 | |
|  * force libbpf to attach kprobe/uprobe in specific mode, -ENOTSUP will
 | |
|  * be returned if it is not supported by the kernel.
 | |
|  */
 | |
| enum probe_attach_mode {
 | |
| 	/* attach probe in latest supported mode by kernel */
 | |
| 	PROBE_ATTACH_MODE_DEFAULT = 0,
 | |
| 	/* attach probe in legacy mode, using debugfs/tracefs */
 | |
| 	PROBE_ATTACH_MODE_LEGACY,
 | |
| 	/* create perf event with perf_event_open() syscall */
 | |
| 	PROBE_ATTACH_MODE_PERF,
 | |
| 	/* attach probe with BPF link */
 | |
| 	PROBE_ATTACH_MODE_LINK,
 | |
| };
 | |
| 
 | |
| struct bpf_kprobe_opts {
 | |
| 	/* size of this struct, for forward/backward compatibility */
 | |
| 	size_t sz;
 | |
| 	/* custom user-provided value fetchable through bpf_get_attach_cookie() */
 | |
| 	__u64 bpf_cookie;
 | |
| 	/* function's offset to install kprobe to */
 | |
| 	size_t offset;
 | |
| 	/* kprobe is return probe */
 | |
| 	bool retprobe;
 | |
| 	/* kprobe attach mode */
 | |
| 	enum probe_attach_mode attach_mode;
 | |
| 	size_t :0;
 | |
| };
 | |
| #define bpf_kprobe_opts__last_field attach_mode
 | |
| 
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_kprobe(const struct bpf_program *prog, bool retprobe,
 | |
| 			   const char *func_name);
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_kprobe_opts(const struct bpf_program *prog,
 | |
|                                 const char *func_name,
 | |
|                                 const struct bpf_kprobe_opts *opts);
 | |
| 
 | |
| struct bpf_kprobe_multi_opts {
 | |
| 	/* size of this struct, for forward/backward compatibility */
 | |
| 	size_t sz;
 | |
| 	/* array of function symbols to attach */
 | |
| 	const char **syms;
 | |
| 	/* array of function addresses to attach */
 | |
| 	const unsigned long *addrs;
 | |
| 	/* array of user-provided values fetchable through bpf_get_attach_cookie */
 | |
| 	const __u64 *cookies;
 | |
| 	/* number of elements in syms/addrs/cookies arrays */
 | |
| 	size_t cnt;
 | |
| 	/* create return kprobes */
 | |
| 	bool retprobe;
 | |
| 	/* create session kprobes */
 | |
| 	bool session;
 | |
| 	size_t :0;
 | |
| };
 | |
| 
 | |
| #define bpf_kprobe_multi_opts__last_field session
 | |
| 
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog,
 | |
| 				      const char *pattern,
 | |
| 				      const struct bpf_kprobe_multi_opts *opts);
 | |
| 
 | |
| struct bpf_uprobe_multi_opts {
 | |
| 	/* size of this struct, for forward/backward compatibility */
 | |
| 	size_t sz;
 | |
| 	/* array of function symbols to attach to */
 | |
| 	const char **syms;
 | |
| 	/* array of function addresses to attach to */
 | |
| 	const unsigned long *offsets;
 | |
| 	/* optional, array of associated ref counter offsets */
 | |
| 	const unsigned long *ref_ctr_offsets;
 | |
| 	/* optional, array of associated BPF cookies */
 | |
| 	const __u64 *cookies;
 | |
| 	/* number of elements in syms/addrs/cookies arrays */
 | |
| 	size_t cnt;
 | |
| 	/* create return uprobes */
 | |
| 	bool retprobe;
 | |
| 	size_t :0;
 | |
| };
 | |
| 
 | |
| #define bpf_uprobe_multi_opts__last_field retprobe
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_program__attach_uprobe_multi()** attaches a BPF program
 | |
|  * to multiple uprobes with uprobe_multi link.
 | |
|  *
 | |
|  * User can specify 2 mutually exclusive set of inputs:
 | |
|  *
 | |
|  *   1) use only path/func_pattern/pid arguments
 | |
|  *
 | |
|  *   2) use path/pid with allowed combinations of
 | |
|  *      syms/offsets/ref_ctr_offsets/cookies/cnt
 | |
|  *
 | |
|  *      - syms and offsets are mutually exclusive
 | |
|  *      - ref_ctr_offsets and cookies are optional
 | |
|  *
 | |
|  *
 | |
|  * @param prog BPF program to attach
 | |
|  * @param pid Process ID to attach the uprobe to, 0 for self (own process),
 | |
|  * -1 for all processes
 | |
|  * @param binary_path Path to binary
 | |
|  * @param func_pattern Regular expression to specify functions to attach
 | |
|  * BPF program to
 | |
|  * @param opts Additional options (see **struct bpf_uprobe_multi_opts**)
 | |
|  * @return 0, on success; negative error code, otherwise
 | |
|  */
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_uprobe_multi(const struct bpf_program *prog,
 | |
| 				 pid_t pid,
 | |
| 				 const char *binary_path,
 | |
| 				 const char *func_pattern,
 | |
| 				 const struct bpf_uprobe_multi_opts *opts);
 | |
| 
 | |
| struct bpf_ksyscall_opts {
 | |
| 	/* size of this struct, for forward/backward compatibility */
 | |
| 	size_t sz;
 | |
| 	/* custom user-provided value fetchable through bpf_get_attach_cookie() */
 | |
| 	__u64 bpf_cookie;
 | |
| 	/* attach as return probe? */
 | |
| 	bool retprobe;
 | |
| 	size_t :0;
 | |
| };
 | |
| #define bpf_ksyscall_opts__last_field retprobe
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_program__attach_ksyscall()** attaches a BPF program
 | |
|  * to kernel syscall handler of a specified syscall. Optionally it's possible
 | |
|  * to request to install retprobe that will be triggered at syscall exit. It's
 | |
|  * also possible to associate BPF cookie (though options).
 | |
|  *
 | |
|  * Libbpf automatically will determine correct full kernel function name,
 | |
|  * which depending on system architecture and kernel version/configuration
 | |
|  * could be of the form __<arch>_sys_<syscall> or __se_sys_<syscall>, and will
 | |
|  * attach specified program using kprobe/kretprobe mechanism.
 | |
|  *
 | |
|  * **bpf_program__attach_ksyscall()** is an API counterpart of declarative
 | |
|  * **SEC("ksyscall/<syscall>")** annotation of BPF programs.
 | |
|  *
 | |
|  * At the moment **SEC("ksyscall")** and **bpf_program__attach_ksyscall()** do
 | |
|  * not handle all the calling convention quirks for mmap(), clone() and compat
 | |
|  * syscalls. It also only attaches to "native" syscall interfaces. If host
 | |
|  * system supports compat syscalls or defines 32-bit syscalls in 64-bit
 | |
|  * kernel, such syscall interfaces won't be attached to by libbpf.
 | |
|  *
 | |
|  * These limitations may or may not change in the future. Therefore it is
 | |
|  * recommended to use SEC("kprobe") for these syscalls or if working with
 | |
|  * compat and 32-bit interfaces is required.
 | |
|  *
 | |
|  * @param prog BPF program to attach
 | |
|  * @param syscall_name Symbolic name of the syscall (e.g., "bpf")
 | |
|  * @param opts Additional options (see **struct bpf_ksyscall_opts**)
 | |
|  * @return Reference to the newly created BPF link; or NULL is returned on
 | |
|  * error, error code is stored in errno
 | |
|  */
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_ksyscall(const struct bpf_program *prog,
 | |
| 			     const char *syscall_name,
 | |
| 			     const struct bpf_ksyscall_opts *opts);
 | |
| 
 | |
| struct bpf_uprobe_opts {
 | |
| 	/* size of this struct, for forward/backward compatibility */
 | |
| 	size_t sz;
 | |
| 	/* offset of kernel reference counted USDT semaphore, added in
 | |
| 	 * a6ca88b241d5 ("trace_uprobe: support reference counter in fd-based uprobe")
 | |
| 	 */
 | |
| 	size_t ref_ctr_offset;
 | |
| 	/* custom user-provided value fetchable through bpf_get_attach_cookie() */
 | |
| 	__u64 bpf_cookie;
 | |
| 	/* uprobe is return probe, invoked at function return time */
 | |
| 	bool retprobe;
 | |
| 	/* Function name to attach to.  Could be an unqualified ("abc") or library-qualified
 | |
| 	 * "abc@LIBXYZ" name.  To specify function entry, func_name should be set while
 | |
| 	 * func_offset argument to bpf_prog__attach_uprobe_opts() should be 0.  To trace an
 | |
| 	 * offset within a function, specify func_name and use func_offset argument to specify
 | |
| 	 * offset within the function.  Shared library functions must specify the shared library
 | |
| 	 * binary_path.
 | |
| 	 */
 | |
| 	const char *func_name;
 | |
| 	/* uprobe attach mode */
 | |
| 	enum probe_attach_mode attach_mode;
 | |
| 	size_t :0;
 | |
| };
 | |
| #define bpf_uprobe_opts__last_field attach_mode
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_program__attach_uprobe()** attaches a BPF program
 | |
|  * to the userspace function which is found by binary path and
 | |
|  * offset. You can optionally specify a particular process to attach
 | |
|  * to. You can also optionally attach the program to the function
 | |
|  * exit instead of entry.
 | |
|  *
 | |
|  * @param prog BPF program to attach
 | |
|  * @param retprobe Attach to function exit
 | |
|  * @param pid Process ID to attach the uprobe to, 0 for self (own process),
 | |
|  * -1 for all processes
 | |
|  * @param binary_path Path to binary that contains the function symbol
 | |
|  * @param func_offset Offset within the binary of the function symbol
 | |
|  * @return Reference to the newly created BPF link; or NULL is returned on error,
 | |
|  * error code is stored in errno
 | |
|  */
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_uprobe(const struct bpf_program *prog, bool retprobe,
 | |
| 			   pid_t pid, const char *binary_path,
 | |
| 			   size_t func_offset);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_program__attach_uprobe_opts()** is just like
 | |
|  * bpf_program__attach_uprobe() except with a options struct
 | |
|  * for various configurations.
 | |
|  *
 | |
|  * @param prog BPF program to attach
 | |
|  * @param pid Process ID to attach the uprobe to, 0 for self (own process),
 | |
|  * -1 for all processes
 | |
|  * @param binary_path Path to binary that contains the function symbol
 | |
|  * @param func_offset Offset within the binary of the function symbol
 | |
|  * @param opts Options for altering program attachment
 | |
|  * @return Reference to the newly created BPF link; or NULL is returned on error,
 | |
|  * error code is stored in errno
 | |
|  */
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid,
 | |
| 				const char *binary_path, size_t func_offset,
 | |
| 				const struct bpf_uprobe_opts *opts);
 | |
| 
 | |
| struct bpf_usdt_opts {
 | |
| 	/* size of this struct, for forward/backward compatibility */
 | |
| 	size_t sz;
 | |
| 	/* custom user-provided value accessible through usdt_cookie() */
 | |
| 	__u64 usdt_cookie;
 | |
| 	size_t :0;
 | |
| };
 | |
| #define bpf_usdt_opts__last_field usdt_cookie
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_program__attach_usdt()** is just like
 | |
|  * bpf_program__attach_uprobe_opts() except it covers USDT (User-space
 | |
|  * Statically Defined Tracepoint) attachment, instead of attaching to
 | |
|  * user-space function entry or exit.
 | |
|  *
 | |
|  * @param prog BPF program to attach
 | |
|  * @param pid Process ID to attach the uprobe to, 0 for self (own process),
 | |
|  * -1 for all processes
 | |
|  * @param binary_path Path to binary that contains provided USDT probe
 | |
|  * @param usdt_provider USDT provider name
 | |
|  * @param usdt_name USDT probe name
 | |
|  * @param opts Options for altering program attachment
 | |
|  * @return Reference to the newly created BPF link; or NULL is returned on error,
 | |
|  * error code is stored in errno
 | |
|  */
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_usdt(const struct bpf_program *prog,
 | |
| 			 pid_t pid, const char *binary_path,
 | |
| 			 const char *usdt_provider, const char *usdt_name,
 | |
| 			 const struct bpf_usdt_opts *opts);
 | |
| 
 | |
| struct bpf_tracepoint_opts {
 | |
| 	/* size of this struct, for forward/backward compatibility */
 | |
| 	size_t sz;
 | |
| 	/* custom user-provided value fetchable through bpf_get_attach_cookie() */
 | |
| 	__u64 bpf_cookie;
 | |
| };
 | |
| #define bpf_tracepoint_opts__last_field bpf_cookie
 | |
| 
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_tracepoint(const struct bpf_program *prog,
 | |
| 			       const char *tp_category,
 | |
| 			       const char *tp_name);
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_tracepoint_opts(const struct bpf_program *prog,
 | |
| 				    const char *tp_category,
 | |
| 				    const char *tp_name,
 | |
| 				    const struct bpf_tracepoint_opts *opts);
 | |
| 
 | |
| struct bpf_raw_tracepoint_opts {
 | |
| 	size_t sz; /* size of this struct for forward/backward compatibility */
 | |
| 	__u64 cookie;
 | |
| 	size_t :0;
 | |
| };
 | |
| #define bpf_raw_tracepoint_opts__last_field cookie
 | |
| 
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_raw_tracepoint(const struct bpf_program *prog,
 | |
| 				   const char *tp_name);
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_raw_tracepoint_opts(const struct bpf_program *prog,
 | |
| 					const char *tp_name,
 | |
| 					struct bpf_raw_tracepoint_opts *opts);
 | |
| 
 | |
| struct bpf_trace_opts {
 | |
| 	/* size of this struct, for forward/backward compatibility */
 | |
| 	size_t sz;
 | |
| 	/* custom user-provided value fetchable through bpf_get_attach_cookie() */
 | |
| 	__u64 cookie;
 | |
| };
 | |
| #define bpf_trace_opts__last_field cookie
 | |
| 
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_trace(const struct bpf_program *prog);
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_trace_opts(const struct bpf_program *prog, const struct bpf_trace_opts *opts);
 | |
| 
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_lsm(const struct bpf_program *prog);
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_cgroup(const struct bpf_program *prog, int cgroup_fd);
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_netns(const struct bpf_program *prog, int netns_fd);
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_sockmap(const struct bpf_program *prog, int map_fd);
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_xdp(const struct bpf_program *prog, int ifindex);
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_freplace(const struct bpf_program *prog,
 | |
| 			     int target_fd, const char *attach_func_name);
 | |
| 
 | |
| struct bpf_netfilter_opts {
 | |
| 	/* size of this struct, for forward/backward compatibility */
 | |
| 	size_t sz;
 | |
| 
 | |
| 	__u32 pf;
 | |
| 	__u32 hooknum;
 | |
| 	__s32 priority;
 | |
| 	__u32 flags;
 | |
| };
 | |
| #define bpf_netfilter_opts__last_field flags
 | |
| 
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_netfilter(const struct bpf_program *prog,
 | |
| 			      const struct bpf_netfilter_opts *opts);
 | |
| 
 | |
| struct bpf_tcx_opts {
 | |
| 	/* size of this struct, for forward/backward compatibility */
 | |
| 	size_t sz;
 | |
| 	__u32 flags;
 | |
| 	__u32 relative_fd;
 | |
| 	__u32 relative_id;
 | |
| 	__u64 expected_revision;
 | |
| 	size_t :0;
 | |
| };
 | |
| #define bpf_tcx_opts__last_field expected_revision
 | |
| 
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_tcx(const struct bpf_program *prog, int ifindex,
 | |
| 			const struct bpf_tcx_opts *opts);
 | |
| 
 | |
| struct bpf_netkit_opts {
 | |
| 	/* size of this struct, for forward/backward compatibility */
 | |
| 	size_t sz;
 | |
| 	__u32 flags;
 | |
| 	__u32 relative_fd;
 | |
| 	__u32 relative_id;
 | |
| 	__u64 expected_revision;
 | |
| 	size_t :0;
 | |
| };
 | |
| #define bpf_netkit_opts__last_field expected_revision
 | |
| 
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_netkit(const struct bpf_program *prog, int ifindex,
 | |
| 			   const struct bpf_netkit_opts *opts);
 | |
| 
 | |
| struct bpf_map;
 | |
| 
 | |
| LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map);
 | |
| LIBBPF_API int bpf_link__update_map(struct bpf_link *link, const struct bpf_map *map);
 | |
| 
 | |
| struct bpf_iter_attach_opts {
 | |
| 	size_t sz; /* size of this struct for forward/backward compatibility */
 | |
| 	union bpf_iter_link_info *link_info;
 | |
| 	__u32 link_info_len;
 | |
| };
 | |
| #define bpf_iter_attach_opts__last_field link_info_len
 | |
| 
 | |
| LIBBPF_API struct bpf_link *
 | |
| bpf_program__attach_iter(const struct bpf_program *prog,
 | |
| 			 const struct bpf_iter_attach_opts *opts);
 | |
| 
 | |
| LIBBPF_API enum bpf_prog_type bpf_program__type(const struct bpf_program *prog);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_program__set_type()** sets the program
 | |
|  * type of the passed BPF program.
 | |
|  * @param prog BPF program to set the program type for
 | |
|  * @param type program type to set the BPF map to have
 | |
|  * @return error code; or 0 if no error. An error occurs
 | |
|  * if the object is already loaded.
 | |
|  *
 | |
|  * This must be called before the BPF object is loaded,
 | |
|  * otherwise it has no effect and an error is returned.
 | |
|  */
 | |
| LIBBPF_API int bpf_program__set_type(struct bpf_program *prog,
 | |
| 				     enum bpf_prog_type type);
 | |
| 
 | |
| LIBBPF_API enum bpf_attach_type
 | |
| bpf_program__expected_attach_type(const struct bpf_program *prog);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_program__set_expected_attach_type()** sets the
 | |
|  * attach type of the passed BPF program. This is used for
 | |
|  * auto-detection of attachment when programs are loaded.
 | |
|  * @param prog BPF program to set the attach type for
 | |
|  * @param type attach type to set the BPF map to have
 | |
|  * @return error code; or 0 if no error. An error occurs
 | |
|  * if the object is already loaded.
 | |
|  *
 | |
|  * This must be called before the BPF object is loaded,
 | |
|  * otherwise it has no effect and an error is returned.
 | |
|  */
 | |
| LIBBPF_API int
 | |
| bpf_program__set_expected_attach_type(struct bpf_program *prog,
 | |
| 				      enum bpf_attach_type type);
 | |
| 
 | |
| LIBBPF_API __u32 bpf_program__flags(const struct bpf_program *prog);
 | |
| LIBBPF_API int bpf_program__set_flags(struct bpf_program *prog, __u32 flags);
 | |
| 
 | |
| /* Per-program log level and log buffer getters/setters.
 | |
|  * See bpf_object_open_opts comments regarding log_level and log_buf
 | |
|  * interactions.
 | |
|  */
 | |
| LIBBPF_API __u32 bpf_program__log_level(const struct bpf_program *prog);
 | |
| LIBBPF_API int bpf_program__set_log_level(struct bpf_program *prog, __u32 log_level);
 | |
| LIBBPF_API const char *bpf_program__log_buf(const struct bpf_program *prog, size_t *log_size);
 | |
| LIBBPF_API int bpf_program__set_log_buf(struct bpf_program *prog, char *log_buf, size_t log_size);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_program__set_attach_target()** sets BTF-based attach target
 | |
|  * for supported BPF program types:
 | |
|  *   - BTF-aware raw tracepoints (tp_btf);
 | |
|  *   - fentry/fexit/fmod_ret;
 | |
|  *   - lsm;
 | |
|  *   - freplace.
 | |
|  * @param prog BPF program to set the attach type for
 | |
|  * @param type attach type to set the BPF map to have
 | |
|  * @return error code; or 0 if no error occurred.
 | |
|  */
 | |
| LIBBPF_API int
 | |
| bpf_program__set_attach_target(struct bpf_program *prog, int attach_prog_fd,
 | |
| 			       const char *attach_func_name);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_object__find_map_by_name()** returns BPF map of
 | |
|  * the given name, if it exists within the passed BPF object
 | |
|  * @param obj BPF object
 | |
|  * @param name name of the BPF map
 | |
|  * @return BPF map instance, if such map exists within the BPF object;
 | |
|  * or NULL otherwise.
 | |
|  */
 | |
| LIBBPF_API struct bpf_map *
 | |
| bpf_object__find_map_by_name(const struct bpf_object *obj, const char *name);
 | |
| 
 | |
| LIBBPF_API int
 | |
| bpf_object__find_map_fd_by_name(const struct bpf_object *obj, const char *name);
 | |
| 
 | |
| LIBBPF_API struct bpf_map *
 | |
| bpf_object__next_map(const struct bpf_object *obj, const struct bpf_map *map);
 | |
| 
 | |
| #define bpf_object__for_each_map(pos, obj)		\
 | |
| 	for ((pos) = bpf_object__next_map((obj), NULL);	\
 | |
| 	     (pos) != NULL;				\
 | |
| 	     (pos) = bpf_object__next_map((obj), (pos)))
 | |
| #define bpf_map__for_each bpf_object__for_each_map
 | |
| 
 | |
| LIBBPF_API struct bpf_map *
 | |
| bpf_object__prev_map(const struct bpf_object *obj, const struct bpf_map *map);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_map__set_autocreate()** sets whether libbpf has to auto-create
 | |
|  * BPF map during BPF object load phase.
 | |
|  * @param map the BPF map instance
 | |
|  * @param autocreate whether to create BPF map during BPF object load
 | |
|  * @return 0 on success; -EBUSY if BPF object was already loaded
 | |
|  *
 | |
|  * **bpf_map__set_autocreate()** allows to opt-out from libbpf auto-creating
 | |
|  * BPF map. By default, libbpf will attempt to create every single BPF map
 | |
|  * defined in BPF object file using BPF_MAP_CREATE command of bpf() syscall
 | |
|  * and fill in map FD in BPF instructions.
 | |
|  *
 | |
|  * This API allows to opt-out of this process for specific map instance. This
 | |
|  * can be useful if host kernel doesn't support such BPF map type or used
 | |
|  * combination of flags and user application wants to avoid creating such
 | |
|  * a map in the first place. User is still responsible to make sure that their
 | |
|  * BPF-side code that expects to use such missing BPF map is recognized by BPF
 | |
|  * verifier as dead code, otherwise BPF verifier will reject such BPF program.
 | |
|  */
 | |
| LIBBPF_API int bpf_map__set_autocreate(struct bpf_map *map, bool autocreate);
 | |
| LIBBPF_API bool bpf_map__autocreate(const struct bpf_map *map);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_map__set_autoattach()** sets whether libbpf has to auto-attach
 | |
|  * map during BPF skeleton attach phase.
 | |
|  * @param map the BPF map instance
 | |
|  * @param autoattach whether to attach map during BPF skeleton attach phase
 | |
|  * @return 0 on success; negative error code, otherwise
 | |
|  */
 | |
| LIBBPF_API int bpf_map__set_autoattach(struct bpf_map *map, bool autoattach);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_map__autoattach()** returns whether BPF map is configured to
 | |
|  * auto-attach during BPF skeleton attach phase.
 | |
|  * @param map the BPF map instance
 | |
|  * @return true if map is set to auto-attach during skeleton attach phase; false, otherwise
 | |
|  */
 | |
| LIBBPF_API bool bpf_map__autoattach(const struct bpf_map *map);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_map__fd()** gets the file descriptor of the passed
 | |
|  * BPF map
 | |
|  * @param map the BPF map instance
 | |
|  * @return the file descriptor; or -EINVAL in case of an error
 | |
|  */
 | |
| LIBBPF_API int bpf_map__fd(const struct bpf_map *map);
 | |
| LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd);
 | |
| /* get map name */
 | |
| LIBBPF_API const char *bpf_map__name(const struct bpf_map *map);
 | |
| /* get/set map type */
 | |
| LIBBPF_API enum bpf_map_type bpf_map__type(const struct bpf_map *map);
 | |
| LIBBPF_API int bpf_map__set_type(struct bpf_map *map, enum bpf_map_type type);
 | |
| /* get/set map size (max_entries) */
 | |
| LIBBPF_API __u32 bpf_map__max_entries(const struct bpf_map *map);
 | |
| LIBBPF_API int bpf_map__set_max_entries(struct bpf_map *map, __u32 max_entries);
 | |
| /* get/set map flags */
 | |
| LIBBPF_API __u32 bpf_map__map_flags(const struct bpf_map *map);
 | |
| LIBBPF_API int bpf_map__set_map_flags(struct bpf_map *map, __u32 flags);
 | |
| /* get/set map NUMA node */
 | |
| LIBBPF_API __u32 bpf_map__numa_node(const struct bpf_map *map);
 | |
| LIBBPF_API int bpf_map__set_numa_node(struct bpf_map *map, __u32 numa_node);
 | |
| /* get/set map key size */
 | |
| LIBBPF_API __u32 bpf_map__key_size(const struct bpf_map *map);
 | |
| LIBBPF_API int bpf_map__set_key_size(struct bpf_map *map, __u32 size);
 | |
| /* get map value size */
 | |
| LIBBPF_API __u32 bpf_map__value_size(const struct bpf_map *map);
 | |
| /**
 | |
|  * @brief **bpf_map__set_value_size()** sets map value size.
 | |
|  * @param map the BPF map instance
 | |
|  * @return 0, on success; negative error, otherwise
 | |
|  *
 | |
|  * There is a special case for maps with associated memory-mapped regions, like
 | |
|  * the global data section maps (bss, data, rodata). When this function is used
 | |
|  * on such a map, the mapped region is resized. Afterward, an attempt is made to
 | |
|  * adjust the corresponding BTF info. This attempt is best-effort and can only
 | |
|  * succeed if the last variable of the data section map is an array. The array
 | |
|  * BTF type is replaced by a new BTF array type with a different length.
 | |
|  * Any previously existing pointers returned from bpf_map__initial_value() or
 | |
|  * corresponding data section skeleton pointer must be reinitialized.
 | |
|  */
 | |
| LIBBPF_API int bpf_map__set_value_size(struct bpf_map *map, __u32 size);
 | |
| /* get map key/value BTF type IDs */
 | |
| LIBBPF_API __u32 bpf_map__btf_key_type_id(const struct bpf_map *map);
 | |
| LIBBPF_API __u32 bpf_map__btf_value_type_id(const struct bpf_map *map);
 | |
| /* get/set map if_index */
 | |
| LIBBPF_API __u32 bpf_map__ifindex(const struct bpf_map *map);
 | |
| LIBBPF_API int bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex);
 | |
| /* get/set map map_extra flags */
 | |
| LIBBPF_API __u64 bpf_map__map_extra(const struct bpf_map *map);
 | |
| LIBBPF_API int bpf_map__set_map_extra(struct bpf_map *map, __u64 map_extra);
 | |
| 
 | |
| LIBBPF_API int bpf_map__set_initial_value(struct bpf_map *map,
 | |
| 					  const void *data, size_t size);
 | |
| LIBBPF_API void *bpf_map__initial_value(const struct bpf_map *map, size_t *psize);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_map__is_internal()** tells the caller whether or not the
 | |
|  * passed map is a special map created by libbpf automatically for things like
 | |
|  * global variables, __ksym externs, Kconfig values, etc
 | |
|  * @param map the bpf_map
 | |
|  * @return true, if the map is an internal map; false, otherwise
 | |
|  */
 | |
| LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_map__set_pin_path()** sets the path attribute that tells where the
 | |
|  * BPF map should be pinned. This does not actually create the 'pin'.
 | |
|  * @param map The bpf_map
 | |
|  * @param path The path
 | |
|  * @return 0, on success; negative error, otherwise
 | |
|  */
 | |
| LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_map__pin_path()** gets the path attribute that tells where the
 | |
|  * BPF map should be pinned.
 | |
|  * @param map The bpf_map
 | |
|  * @return The path string; which can be NULL
 | |
|  */
 | |
| LIBBPF_API const char *bpf_map__pin_path(const struct bpf_map *map);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_map__is_pinned()** tells the caller whether or not the
 | |
|  * passed map has been pinned via a 'pin' file.
 | |
|  * @param map The bpf_map
 | |
|  * @return true, if the map is pinned; false, otherwise
 | |
|  */
 | |
| LIBBPF_API bool bpf_map__is_pinned(const struct bpf_map *map);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_map__pin()** creates a file that serves as a 'pin'
 | |
|  * for the BPF map. This increments the reference count on the
 | |
|  * BPF map which will keep the BPF map loaded even after the
 | |
|  * userspace process which loaded it has exited.
 | |
|  * @param map The bpf_map to pin
 | |
|  * @param path A file path for the 'pin'
 | |
|  * @return 0, on success; negative error, otherwise
 | |
|  *
 | |
|  * If `path` is NULL the maps `pin_path` attribute will be used. If this is
 | |
|  * also NULL, an error will be returned and the map will not be pinned.
 | |
|  */
 | |
| LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_map__unpin()** removes the file that serves as a
 | |
|  * 'pin' for the BPF map.
 | |
|  * @param map The bpf_map to unpin
 | |
|  * @param path A file path for the 'pin'
 | |
|  * @return 0, on success; negative error, otherwise
 | |
|  *
 | |
|  * The `path` parameter can be NULL, in which case the `pin_path`
 | |
|  * map attribute is unpinned. If both the `path` parameter and
 | |
|  * `pin_path` map attribute are set, they must be equal.
 | |
|  */
 | |
| LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path);
 | |
| 
 | |
| LIBBPF_API int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd);
 | |
| LIBBPF_API struct bpf_map *bpf_map__inner_map(struct bpf_map *map);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_map__lookup_elem()** allows to lookup BPF map value
 | |
|  * corresponding to provided key.
 | |
|  * @param map BPF map to lookup element in
 | |
|  * @param key pointer to memory containing bytes of the key used for lookup
 | |
|  * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size**
 | |
|  * @param value pointer to memory in which looked up value will be stored
 | |
|  * @param value_sz size in byte of value data memory; it has to match BPF map
 | |
|  * definition's **value_size**. For per-CPU BPF maps value size has to be
 | |
|  * a product of BPF map value size and number of possible CPUs in the system
 | |
|  * (could be fetched with **libbpf_num_possible_cpus()**). Note also that for
 | |
|  * per-CPU values value size has to be aligned up to closest 8 bytes for
 | |
|  * alignment reasons, so expected size is: `round_up(value_size, 8)
 | |
|  * * libbpf_num_possible_cpus()`.
 | |
|  * @flags extra flags passed to kernel for this operation
 | |
|  * @return 0, on success; negative error, otherwise
 | |
|  *
 | |
|  * **bpf_map__lookup_elem()** is high-level equivalent of
 | |
|  * **bpf_map_lookup_elem()** API with added check for key and value size.
 | |
|  */
 | |
| LIBBPF_API int bpf_map__lookup_elem(const struct bpf_map *map,
 | |
| 				    const void *key, size_t key_sz,
 | |
| 				    void *value, size_t value_sz, __u64 flags);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_map__update_elem()** allows to insert or update value in BPF
 | |
|  * map that corresponds to provided key.
 | |
|  * @param map BPF map to insert to or update element in
 | |
|  * @param key pointer to memory containing bytes of the key
 | |
|  * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size**
 | |
|  * @param value pointer to memory containing bytes of the value
 | |
|  * @param value_sz size in byte of value data memory; it has to match BPF map
 | |
|  * definition's **value_size**. For per-CPU BPF maps value size has to be
 | |
|  * a product of BPF map value size and number of possible CPUs in the system
 | |
|  * (could be fetched with **libbpf_num_possible_cpus()**). Note also that for
 | |
|  * per-CPU values value size has to be aligned up to closest 8 bytes for
 | |
|  * alignment reasons, so expected size is: `round_up(value_size, 8)
 | |
|  * * libbpf_num_possible_cpus()`.
 | |
|  * @flags extra flags passed to kernel for this operation
 | |
|  * @return 0, on success; negative error, otherwise
 | |
|  *
 | |
|  * **bpf_map__update_elem()** is high-level equivalent of
 | |
|  * **bpf_map_update_elem()** API with added check for key and value size.
 | |
|  */
 | |
| LIBBPF_API int bpf_map__update_elem(const struct bpf_map *map,
 | |
| 				    const void *key, size_t key_sz,
 | |
| 				    const void *value, size_t value_sz, __u64 flags);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_map__delete_elem()** allows to delete element in BPF map that
 | |
|  * corresponds to provided key.
 | |
|  * @param map BPF map to delete element from
 | |
|  * @param key pointer to memory containing bytes of the key
 | |
|  * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size**
 | |
|  * @flags extra flags passed to kernel for this operation
 | |
|  * @return 0, on success; negative error, otherwise
 | |
|  *
 | |
|  * **bpf_map__delete_elem()** is high-level equivalent of
 | |
|  * **bpf_map_delete_elem()** API with added check for key size.
 | |
|  */
 | |
| LIBBPF_API int bpf_map__delete_elem(const struct bpf_map *map,
 | |
| 				    const void *key, size_t key_sz, __u64 flags);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_map__lookup_and_delete_elem()** allows to lookup BPF map value
 | |
|  * corresponding to provided key and atomically delete it afterwards.
 | |
|  * @param map BPF map to lookup element in
 | |
|  * @param key pointer to memory containing bytes of the key used for lookup
 | |
|  * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size**
 | |
|  * @param value pointer to memory in which looked up value will be stored
 | |
|  * @param value_sz size in byte of value data memory; it has to match BPF map
 | |
|  * definition's **value_size**. For per-CPU BPF maps value size has to be
 | |
|  * a product of BPF map value size and number of possible CPUs in the system
 | |
|  * (could be fetched with **libbpf_num_possible_cpus()**). Note also that for
 | |
|  * per-CPU values value size has to be aligned up to closest 8 bytes for
 | |
|  * alignment reasons, so expected size is: `round_up(value_size, 8)
 | |
|  * * libbpf_num_possible_cpus()`.
 | |
|  * @flags extra flags passed to kernel for this operation
 | |
|  * @return 0, on success; negative error, otherwise
 | |
|  *
 | |
|  * **bpf_map__lookup_and_delete_elem()** is high-level equivalent of
 | |
|  * **bpf_map_lookup_and_delete_elem()** API with added check for key and value size.
 | |
|  */
 | |
| LIBBPF_API int bpf_map__lookup_and_delete_elem(const struct bpf_map *map,
 | |
| 					       const void *key, size_t key_sz,
 | |
| 					       void *value, size_t value_sz, __u64 flags);
 | |
| 
 | |
| /**
 | |
|  * @brief **bpf_map__get_next_key()** allows to iterate BPF map keys by
 | |
|  * fetching next key that follows current key.
 | |
|  * @param map BPF map to fetch next key from
 | |
|  * @param cur_key pointer to memory containing bytes of current key or NULL to
 | |
|  * fetch the first key
 | |
|  * @param next_key pointer to memory to write next key into
 | |
|  * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size**
 | |
|  * @return 0, on success; -ENOENT if **cur_key** is the last key in BPF map;
 | |
|  * negative error, otherwise
 | |
|  *
 | |
|  * **bpf_map__get_next_key()** is high-level equivalent of
 | |
|  * **bpf_map_get_next_key()** API with added check for key size.
 | |
|  */
 | |
| LIBBPF_API int bpf_map__get_next_key(const struct bpf_map *map,
 | |
| 				     const void *cur_key, void *next_key, size_t key_sz);
 | |
| 
 | |
| struct bpf_xdp_set_link_opts {
 | |
| 	size_t sz;
 | |
| 	int old_fd;
 | |
| 	size_t :0;
 | |
| };
 | |
| #define bpf_xdp_set_link_opts__last_field old_fd
 | |
| 
 | |
| struct bpf_xdp_attach_opts {
 | |
| 	size_t sz;
 | |
| 	int old_prog_fd;
 | |
| 	size_t :0;
 | |
| };
 | |
| #define bpf_xdp_attach_opts__last_field old_prog_fd
 | |
| 
 | |
| struct bpf_xdp_query_opts {
 | |
| 	size_t sz;
 | |
| 	__u32 prog_id;		/* output */
 | |
| 	__u32 drv_prog_id;	/* output */
 | |
| 	__u32 hw_prog_id;	/* output */
 | |
| 	__u32 skb_prog_id;	/* output */
 | |
| 	__u8 attach_mode;	/* output */
 | |
| 	__u64 feature_flags;	/* output */
 | |
| 	__u32 xdp_zc_max_segs;	/* output */
 | |
| 	size_t :0;
 | |
| };
 | |
| #define bpf_xdp_query_opts__last_field xdp_zc_max_segs
 | |
| 
 | |
| LIBBPF_API int bpf_xdp_attach(int ifindex, int prog_fd, __u32 flags,
 | |
| 			      const struct bpf_xdp_attach_opts *opts);
 | |
| LIBBPF_API int bpf_xdp_detach(int ifindex, __u32 flags,
 | |
| 			      const struct bpf_xdp_attach_opts *opts);
 | |
| LIBBPF_API int bpf_xdp_query(int ifindex, int flags, struct bpf_xdp_query_opts *opts);
 | |
| LIBBPF_API int bpf_xdp_query_id(int ifindex, int flags, __u32 *prog_id);
 | |
| 
 | |
| /* TC related API */
 | |
| enum bpf_tc_attach_point {
 | |
| 	BPF_TC_INGRESS = 1 << 0,
 | |
| 	BPF_TC_EGRESS  = 1 << 1,
 | |
| 	BPF_TC_CUSTOM  = 1 << 2,
 | |
| };
 | |
| 
 | |
| #define BPF_TC_PARENT(a, b) 	\
 | |
| 	((((a) << 16) & 0xFFFF0000U) | ((b) & 0x0000FFFFU))
 | |
| 
 | |
| enum bpf_tc_flags {
 | |
| 	BPF_TC_F_REPLACE = 1 << 0,
 | |
| };
 | |
| 
 | |
| struct bpf_tc_hook {
 | |
| 	size_t sz;
 | |
| 	int ifindex;
 | |
| 	enum bpf_tc_attach_point attach_point;
 | |
| 	__u32 parent;
 | |
| 	size_t :0;
 | |
| };
 | |
| #define bpf_tc_hook__last_field parent
 | |
| 
 | |
| struct bpf_tc_opts {
 | |
| 	size_t sz;
 | |
| 	int prog_fd;
 | |
| 	__u32 flags;
 | |
| 	__u32 prog_id;
 | |
| 	__u32 handle;
 | |
| 	__u32 priority;
 | |
| 	size_t :0;
 | |
| };
 | |
| #define bpf_tc_opts__last_field priority
 | |
| 
 | |
| LIBBPF_API int bpf_tc_hook_create(struct bpf_tc_hook *hook);
 | |
| LIBBPF_API int bpf_tc_hook_destroy(struct bpf_tc_hook *hook);
 | |
| LIBBPF_API int bpf_tc_attach(const struct bpf_tc_hook *hook,
 | |
| 			     struct bpf_tc_opts *opts);
 | |
| LIBBPF_API int bpf_tc_detach(const struct bpf_tc_hook *hook,
 | |
| 			     const struct bpf_tc_opts *opts);
 | |
| LIBBPF_API int bpf_tc_query(const struct bpf_tc_hook *hook,
 | |
| 			    struct bpf_tc_opts *opts);
 | |
| 
 | |
| /* Ring buffer APIs */
 | |
| struct ring_buffer;
 | |
| struct ring;
 | |
| struct user_ring_buffer;
 | |
| 
 | |
| typedef int (*ring_buffer_sample_fn)(void *ctx, void *data, size_t size);
 | |
| 
 | |
| struct ring_buffer_opts {
 | |
| 	size_t sz; /* size of this struct, for forward/backward compatibility */
 | |
| };
 | |
| 
 | |
| #define ring_buffer_opts__last_field sz
 | |
| 
 | |
| LIBBPF_API struct ring_buffer *
 | |
| ring_buffer__new(int map_fd, ring_buffer_sample_fn sample_cb, void *ctx,
 | |
| 		 const struct ring_buffer_opts *opts);
 | |
| LIBBPF_API void ring_buffer__free(struct ring_buffer *rb);
 | |
| LIBBPF_API int ring_buffer__add(struct ring_buffer *rb, int map_fd,
 | |
| 				ring_buffer_sample_fn sample_cb, void *ctx);
 | |
| LIBBPF_API int ring_buffer__poll(struct ring_buffer *rb, int timeout_ms);
 | |
| LIBBPF_API int ring_buffer__consume(struct ring_buffer *rb);
 | |
| LIBBPF_API int ring_buffer__consume_n(struct ring_buffer *rb, size_t n);
 | |
| LIBBPF_API int ring_buffer__epoll_fd(const struct ring_buffer *rb);
 | |
| 
 | |
| /**
 | |
|  * @brief **ring_buffer__ring()** returns the ringbuffer object inside a given
 | |
|  * ringbuffer manager representing a single BPF_MAP_TYPE_RINGBUF map instance.
 | |
|  *
 | |
|  * @param rb A ringbuffer manager object.
 | |
|  * @param idx An index into the ringbuffers contained within the ringbuffer
 | |
|  * manager object. The index is 0-based and corresponds to the order in which
 | |
|  * ring_buffer__add was called.
 | |
|  * @return A ringbuffer object on success; NULL and errno set if the index is
 | |
|  * invalid.
 | |
|  */
 | |
| LIBBPF_API struct ring *ring_buffer__ring(struct ring_buffer *rb,
 | |
| 					  unsigned int idx);
 | |
| 
 | |
| /**
 | |
|  * @brief **ring__consumer_pos()** returns the current consumer position in the
 | |
|  * given ringbuffer.
 | |
|  *
 | |
|  * @param r A ringbuffer object.
 | |
|  * @return The current consumer position.
 | |
|  */
 | |
| LIBBPF_API unsigned long ring__consumer_pos(const struct ring *r);
 | |
| 
 | |
| /**
 | |
|  * @brief **ring__producer_pos()** returns the current producer position in the
 | |
|  * given ringbuffer.
 | |
|  *
 | |
|  * @param r A ringbuffer object.
 | |
|  * @return The current producer position.
 | |
|  */
 | |
| LIBBPF_API unsigned long ring__producer_pos(const struct ring *r);
 | |
| 
 | |
| /**
 | |
|  * @brief **ring__avail_data_size()** returns the number of bytes in the
 | |
|  * ringbuffer not yet consumed. This has no locking associated with it, so it
 | |
|  * can be inaccurate if operations are ongoing while this is called. However, it
 | |
|  * should still show the correct trend over the long-term.
 | |
|  *
 | |
|  * @param r A ringbuffer object.
 | |
|  * @return The number of bytes not yet consumed.
 | |
|  */
 | |
| LIBBPF_API size_t ring__avail_data_size(const struct ring *r);
 | |
| 
 | |
| /**
 | |
|  * @brief **ring__size()** returns the total size of the ringbuffer's map data
 | |
|  * area (excluding special producer/consumer pages). Effectively this gives the
 | |
|  * amount of usable bytes of data inside the ringbuffer.
 | |
|  *
 | |
|  * @param r A ringbuffer object.
 | |
|  * @return The total size of the ringbuffer map data area.
 | |
|  */
 | |
| LIBBPF_API size_t ring__size(const struct ring *r);
 | |
| 
 | |
| /**
 | |
|  * @brief **ring__map_fd()** returns the file descriptor underlying the given
 | |
|  * ringbuffer.
 | |
|  *
 | |
|  * @param r A ringbuffer object.
 | |
|  * @return The underlying ringbuffer file descriptor
 | |
|  */
 | |
| LIBBPF_API int ring__map_fd(const struct ring *r);
 | |
| 
 | |
| /**
 | |
|  * @brief **ring__consume()** consumes available ringbuffer data without event
 | |
|  * polling.
 | |
|  *
 | |
|  * @param r A ringbuffer object.
 | |
|  * @return The number of records consumed (or INT_MAX, whichever is less), or
 | |
|  * a negative number if any of the callbacks return an error.
 | |
|  */
 | |
| LIBBPF_API int ring__consume(struct ring *r);
 | |
| 
 | |
| /**
 | |
|  * @brief **ring__consume_n()** consumes up to a requested amount of items from
 | |
|  * a ringbuffer without event polling.
 | |
|  *
 | |
|  * @param r A ringbuffer object.
 | |
|  * @param n Maximum amount of items to consume.
 | |
|  * @return The number of items consumed, or a negative number if any of the
 | |
|  * callbacks return an error.
 | |
|  */
 | |
| LIBBPF_API int ring__consume_n(struct ring *r, size_t n);
 | |
| 
 | |
| struct user_ring_buffer_opts {
 | |
| 	size_t sz; /* size of this struct, for forward/backward compatibility */
 | |
| };
 | |
| 
 | |
| #define user_ring_buffer_opts__last_field sz
 | |
| 
 | |
| /**
 | |
|  * @brief **user_ring_buffer__new()** creates a new instance of a user ring
 | |
|  * buffer.
 | |
|  *
 | |
|  * @param map_fd A file descriptor to a BPF_MAP_TYPE_USER_RINGBUF map.
 | |
|  * @param opts Options for how the ring buffer should be created.
 | |
|  * @return A user ring buffer on success; NULL and errno being set on a
 | |
|  * failure.
 | |
|  */
 | |
| LIBBPF_API struct user_ring_buffer *
 | |
| user_ring_buffer__new(int map_fd, const struct user_ring_buffer_opts *opts);
 | |
| 
 | |
| /**
 | |
|  * @brief **user_ring_buffer__reserve()** reserves a pointer to a sample in the
 | |
|  * user ring buffer.
 | |
|  * @param rb A pointer to a user ring buffer.
 | |
|  * @param size The size of the sample, in bytes.
 | |
|  * @return A pointer to an 8-byte aligned reserved region of the user ring
 | |
|  * buffer; NULL, and errno being set if a sample could not be reserved.
 | |
|  *
 | |
|  * This function is *not* thread safe, and callers must synchronize accessing
 | |
|  * this function if there are multiple producers.  If a size is requested that
 | |
|  * is larger than the size of the entire ring buffer, errno will be set to
 | |
|  * E2BIG and NULL is returned. If the ring buffer could accommodate the size,
 | |
|  * but currently does not have enough space, errno is set to ENOSPC and NULL is
 | |
|  * returned.
 | |
|  *
 | |
|  * After initializing the sample, callers must invoke
 | |
|  * **user_ring_buffer__submit()** to post the sample to the kernel. Otherwise,
 | |
|  * the sample must be freed with **user_ring_buffer__discard()**.
 | |
|  */
 | |
| LIBBPF_API void *user_ring_buffer__reserve(struct user_ring_buffer *rb, __u32 size);
 | |
| 
 | |
| /**
 | |
|  * @brief **user_ring_buffer__reserve_blocking()** reserves a record in the
 | |
|  * ring buffer, possibly blocking for up to @timeout_ms until a sample becomes
 | |
|  * available.
 | |
|  * @param rb The user ring buffer.
 | |
|  * @param size The size of the sample, in bytes.
 | |
|  * @param timeout_ms The amount of time, in milliseconds, for which the caller
 | |
|  * should block when waiting for a sample. -1 causes the caller to block
 | |
|  * indefinitely.
 | |
|  * @return A pointer to an 8-byte aligned reserved region of the user ring
 | |
|  * buffer; NULL, and errno being set if a sample could not be reserved.
 | |
|  *
 | |
|  * This function is *not* thread safe, and callers must synchronize
 | |
|  * accessing this function if there are multiple producers
 | |
|  *
 | |
|  * If **timeout_ms** is -1, the function will block indefinitely until a sample
 | |
|  * becomes available. Otherwise, **timeout_ms** must be non-negative, or errno
 | |
|  * is set to EINVAL, and NULL is returned. If **timeout_ms** is 0, no blocking
 | |
|  * will occur and the function will return immediately after attempting to
 | |
|  * reserve a sample.
 | |
|  *
 | |
|  * If **size** is larger than the size of the entire ring buffer, errno is set
 | |
|  * to E2BIG and NULL is returned. If the ring buffer could accommodate
 | |
|  * **size**, but currently does not have enough space, the caller will block
 | |
|  * until at most **timeout_ms** has elapsed. If insufficient space is available
 | |
|  * at that time, errno is set to ENOSPC, and NULL is returned.
 | |
|  *
 | |
|  * The kernel guarantees that it will wake up this thread to check if
 | |
|  * sufficient space is available in the ring buffer at least once per
 | |
|  * invocation of the **bpf_ringbuf_drain()** helper function, provided that at
 | |
|  * least one sample is consumed, and the BPF program did not invoke the
 | |
|  * function with BPF_RB_NO_WAKEUP. A wakeup may occur sooner than that, but the
 | |
|  * kernel does not guarantee this. If the helper function is invoked with
 | |
|  * BPF_RB_FORCE_WAKEUP, a wakeup event will be sent even if no sample is
 | |
|  * consumed.
 | |
|  *
 | |
|  * When a sample of size **size** is found within **timeout_ms**, a pointer to
 | |
|  * the sample is returned. After initializing the sample, callers must invoke
 | |
|  * **user_ring_buffer__submit()** to post the sample to the ring buffer.
 | |
|  * Otherwise, the sample must be freed with **user_ring_buffer__discard()**.
 | |
|  */
 | |
| LIBBPF_API void *user_ring_buffer__reserve_blocking(struct user_ring_buffer *rb,
 | |
| 						    __u32 size,
 | |
| 						    int timeout_ms);
 | |
| 
 | |
| /**
 | |
|  * @brief **user_ring_buffer__submit()** submits a previously reserved sample
 | |
|  * into the ring buffer.
 | |
|  * @param rb The user ring buffer.
 | |
|  * @param sample A reserved sample.
 | |
|  *
 | |
|  * It is not necessary to synchronize amongst multiple producers when invoking
 | |
|  * this function.
 | |
|  */
 | |
| LIBBPF_API void user_ring_buffer__submit(struct user_ring_buffer *rb, void *sample);
 | |
| 
 | |
| /**
 | |
|  * @brief **user_ring_buffer__discard()** discards a previously reserved sample.
 | |
|  * @param rb The user ring buffer.
 | |
|  * @param sample A reserved sample.
 | |
|  *
 | |
|  * It is not necessary to synchronize amongst multiple producers when invoking
 | |
|  * this function.
 | |
|  */
 | |
| LIBBPF_API void user_ring_buffer__discard(struct user_ring_buffer *rb, void *sample);
 | |
| 
 | |
| /**
 | |
|  * @brief **user_ring_buffer__free()** frees a ring buffer that was previously
 | |
|  * created with **user_ring_buffer__new()**.
 | |
|  * @param rb The user ring buffer being freed.
 | |
|  */
 | |
| LIBBPF_API void user_ring_buffer__free(struct user_ring_buffer *rb);
 | |
| 
 | |
| /* Perf buffer APIs */
 | |
| struct perf_buffer;
 | |
| 
 | |
| typedef void (*perf_buffer_sample_fn)(void *ctx, int cpu,
 | |
| 				      void *data, __u32 size);
 | |
| typedef void (*perf_buffer_lost_fn)(void *ctx, int cpu, __u64 cnt);
 | |
| 
 | |
| /* common use perf buffer options */
 | |
| struct perf_buffer_opts {
 | |
| 	size_t sz;
 | |
| 	__u32 sample_period;
 | |
| 	size_t :0;
 | |
| };
 | |
| #define perf_buffer_opts__last_field sample_period
 | |
| 
 | |
| /**
 | |
|  * @brief **perf_buffer__new()** creates BPF perfbuf manager for a specified
 | |
|  * BPF_PERF_EVENT_ARRAY map
 | |
|  * @param map_fd FD of BPF_PERF_EVENT_ARRAY BPF map that will be used by BPF
 | |
|  * code to send data over to user-space
 | |
|  * @param page_cnt number of memory pages allocated for each per-CPU buffer
 | |
|  * @param sample_cb function called on each received data record
 | |
|  * @param lost_cb function called when record loss has occurred
 | |
|  * @param ctx user-provided extra context passed into *sample_cb* and *lost_cb*
 | |
|  * @return a new instance of struct perf_buffer on success, NULL on error with
 | |
|  * *errno* containing an error code
 | |
|  */
 | |
| LIBBPF_API struct perf_buffer *
 | |
| perf_buffer__new(int map_fd, size_t page_cnt,
 | |
| 		 perf_buffer_sample_fn sample_cb, perf_buffer_lost_fn lost_cb, void *ctx,
 | |
| 		 const struct perf_buffer_opts *opts);
 | |
| 
 | |
| enum bpf_perf_event_ret {
 | |
| 	LIBBPF_PERF_EVENT_DONE	= 0,
 | |
| 	LIBBPF_PERF_EVENT_ERROR	= -1,
 | |
| 	LIBBPF_PERF_EVENT_CONT	= -2,
 | |
| };
 | |
| 
 | |
| struct perf_event_header;
 | |
| 
 | |
| typedef enum bpf_perf_event_ret
 | |
| (*perf_buffer_event_fn)(void *ctx, int cpu, struct perf_event_header *event);
 | |
| 
 | |
| /* raw perf buffer options, giving most power and control */
 | |
| struct perf_buffer_raw_opts {
 | |
| 	size_t sz;
 | |
| 	long :0;
 | |
| 	long :0;
 | |
| 	/* if cpu_cnt == 0, open all on all possible CPUs (up to the number of
 | |
| 	 * max_entries of given PERF_EVENT_ARRAY map)
 | |
| 	 */
 | |
| 	int cpu_cnt;
 | |
| 	/* if cpu_cnt > 0, cpus is an array of CPUs to open ring buffers on */
 | |
| 	int *cpus;
 | |
| 	/* if cpu_cnt > 0, map_keys specify map keys to set per-CPU FDs for */
 | |
| 	int *map_keys;
 | |
| };
 | |
| #define perf_buffer_raw_opts__last_field map_keys
 | |
| 
 | |
| struct perf_event_attr;
 | |
| 
 | |
| LIBBPF_API struct perf_buffer *
 | |
| perf_buffer__new_raw(int map_fd, size_t page_cnt, struct perf_event_attr *attr,
 | |
| 		     perf_buffer_event_fn event_cb, void *ctx,
 | |
| 		     const struct perf_buffer_raw_opts *opts);
 | |
| 
 | |
| LIBBPF_API void perf_buffer__free(struct perf_buffer *pb);
 | |
| LIBBPF_API int perf_buffer__epoll_fd(const struct perf_buffer *pb);
 | |
| LIBBPF_API int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms);
 | |
| LIBBPF_API int perf_buffer__consume(struct perf_buffer *pb);
 | |
| LIBBPF_API int perf_buffer__consume_buffer(struct perf_buffer *pb, size_t buf_idx);
 | |
| LIBBPF_API size_t perf_buffer__buffer_cnt(const struct perf_buffer *pb);
 | |
| LIBBPF_API int perf_buffer__buffer_fd(const struct perf_buffer *pb, size_t buf_idx);
 | |
| /**
 | |
|  * @brief **perf_buffer__buffer()** returns the per-cpu raw mmap()'ed underlying
 | |
|  * memory region of the ring buffer.
 | |
|  * This ring buffer can be used to implement a custom events consumer.
 | |
|  * The ring buffer starts with the *struct perf_event_mmap_page*, which
 | |
|  * holds the ring buffer management fields, when accessing the header
 | |
|  * structure it's important to be SMP aware.
 | |
|  * You can refer to *perf_event_read_simple* for a simple example.
 | |
|  * @param pb the perf buffer structure
 | |
|  * @param buf_idx the buffer index to retrieve
 | |
|  * @param buf (out) gets the base pointer of the mmap()'ed memory
 | |
|  * @param buf_size (out) gets the size of the mmap()'ed region
 | |
|  * @return 0 on success, negative error code for failure
 | |
|  */
 | |
| LIBBPF_API int perf_buffer__buffer(struct perf_buffer *pb, int buf_idx, void **buf,
 | |
| 				   size_t *buf_size);
 | |
| 
 | |
| struct bpf_prog_linfo;
 | |
| struct bpf_prog_info;
 | |
| 
 | |
| LIBBPF_API void bpf_prog_linfo__free(struct bpf_prog_linfo *prog_linfo);
 | |
| LIBBPF_API struct bpf_prog_linfo *
 | |
| bpf_prog_linfo__new(const struct bpf_prog_info *info);
 | |
| LIBBPF_API const struct bpf_line_info *
 | |
| bpf_prog_linfo__lfind_addr_func(const struct bpf_prog_linfo *prog_linfo,
 | |
| 				__u64 addr, __u32 func_idx, __u32 nr_skip);
 | |
| LIBBPF_API const struct bpf_line_info *
 | |
| bpf_prog_linfo__lfind(const struct bpf_prog_linfo *prog_linfo,
 | |
| 		      __u32 insn_off, __u32 nr_skip);
 | |
| 
 | |
| /*
 | |
|  * Probe for supported system features
 | |
|  *
 | |
|  * Note that running many of these probes in a short amount of time can cause
 | |
|  * the kernel to reach the maximal size of lockable memory allowed for the
 | |
|  * user, causing subsequent probes to fail. In this case, the caller may want
 | |
|  * to adjust that limit with setrlimit().
 | |
|  */
 | |
| 
 | |
| /**
 | |
|  * @brief **libbpf_probe_bpf_prog_type()** detects if host kernel supports
 | |
|  * BPF programs of a given type.
 | |
|  * @param prog_type BPF program type to detect kernel support for
 | |
|  * @param opts reserved for future extensibility, should be NULL
 | |
|  * @return 1, if given program type is supported; 0, if given program type is
 | |
|  * not supported; negative error code if feature detection failed or can't be
 | |
|  * performed
 | |
|  *
 | |
|  * Make sure the process has required set of CAP_* permissions (or runs as
 | |
|  * root) when performing feature checking.
 | |
|  */
 | |
| LIBBPF_API int libbpf_probe_bpf_prog_type(enum bpf_prog_type prog_type, const void *opts);
 | |
| /**
 | |
|  * @brief **libbpf_probe_bpf_map_type()** detects if host kernel supports
 | |
|  * BPF maps of a given type.
 | |
|  * @param map_type BPF map type to detect kernel support for
 | |
|  * @param opts reserved for future extensibility, should be NULL
 | |
|  * @return 1, if given map type is supported; 0, if given map type is
 | |
|  * not supported; negative error code if feature detection failed or can't be
 | |
|  * performed
 | |
|  *
 | |
|  * Make sure the process has required set of CAP_* permissions (or runs as
 | |
|  * root) when performing feature checking.
 | |
|  */
 | |
| LIBBPF_API int libbpf_probe_bpf_map_type(enum bpf_map_type map_type, const void *opts);
 | |
| /**
 | |
|  * @brief **libbpf_probe_bpf_helper()** detects if host kernel supports the
 | |
|  * use of a given BPF helper from specified BPF program type.
 | |
|  * @param prog_type BPF program type used to check the support of BPF helper
 | |
|  * @param helper_id BPF helper ID (enum bpf_func_id) to check support for
 | |
|  * @param opts reserved for future extensibility, should be NULL
 | |
|  * @return 1, if given combination of program type and helper is supported; 0,
 | |
|  * if the combination is not supported; negative error code if feature
 | |
|  * detection for provided input arguments failed or can't be performed
 | |
|  *
 | |
|  * Make sure the process has required set of CAP_* permissions (or runs as
 | |
|  * root) when performing feature checking.
 | |
|  */
 | |
| LIBBPF_API int libbpf_probe_bpf_helper(enum bpf_prog_type prog_type,
 | |
| 				       enum bpf_func_id helper_id, const void *opts);
 | |
| 
 | |
| /**
 | |
|  * @brief **libbpf_num_possible_cpus()** is a helper function to get the
 | |
|  * number of possible CPUs that the host kernel supports and expects.
 | |
|  * @return number of possible CPUs; or error code on failure
 | |
|  *
 | |
|  * Example usage:
 | |
|  *
 | |
|  *     int ncpus = libbpf_num_possible_cpus();
 | |
|  *     if (ncpus < 0) {
 | |
|  *          // error handling
 | |
|  *     }
 | |
|  *     long values[ncpus];
 | |
|  *     bpf_map_lookup_elem(per_cpu_map_fd, key, values);
 | |
|  */
 | |
| LIBBPF_API int libbpf_num_possible_cpus(void);
 | |
| 
 | |
| struct bpf_map_skeleton {
 | |
| 	const char *name;
 | |
| 	struct bpf_map **map;
 | |
| 	void **mmaped;
 | |
| 	struct bpf_link **link;
 | |
| };
 | |
| 
 | |
| struct bpf_prog_skeleton {
 | |
| 	const char *name;
 | |
| 	struct bpf_program **prog;
 | |
| 	struct bpf_link **link;
 | |
| };
 | |
| 
 | |
| struct bpf_object_skeleton {
 | |
| 	size_t sz; /* size of this struct, for forward/backward compatibility */
 | |
| 
 | |
| 	const char *name;
 | |
| 	const void *data;
 | |
| 	size_t data_sz;
 | |
| 
 | |
| 	struct bpf_object **obj;
 | |
| 
 | |
| 	int map_cnt;
 | |
| 	int map_skel_sz; /* sizeof(struct bpf_map_skeleton) */
 | |
| 	struct bpf_map_skeleton *maps;
 | |
| 
 | |
| 	int prog_cnt;
 | |
| 	int prog_skel_sz; /* sizeof(struct bpf_prog_skeleton) */
 | |
| 	struct bpf_prog_skeleton *progs;
 | |
| };
 | |
| 
 | |
| LIBBPF_API int
 | |
| bpf_object__open_skeleton(struct bpf_object_skeleton *s,
 | |
| 			  const struct bpf_object_open_opts *opts);
 | |
| LIBBPF_API int bpf_object__load_skeleton(struct bpf_object_skeleton *s);
 | |
| LIBBPF_API int bpf_object__attach_skeleton(struct bpf_object_skeleton *s);
 | |
| LIBBPF_API void bpf_object__detach_skeleton(struct bpf_object_skeleton *s);
 | |
| LIBBPF_API void bpf_object__destroy_skeleton(struct bpf_object_skeleton *s);
 | |
| 
 | |
| struct bpf_var_skeleton {
 | |
| 	const char *name;
 | |
| 	struct bpf_map **map;
 | |
| 	void **addr;
 | |
| };
 | |
| 
 | |
| struct bpf_object_subskeleton {
 | |
| 	size_t sz; /* size of this struct, for forward/backward compatibility */
 | |
| 
 | |
| 	const struct bpf_object *obj;
 | |
| 
 | |
| 	int map_cnt;
 | |
| 	int map_skel_sz; /* sizeof(struct bpf_map_skeleton) */
 | |
| 	struct bpf_map_skeleton *maps;
 | |
| 
 | |
| 	int prog_cnt;
 | |
| 	int prog_skel_sz; /* sizeof(struct bpf_prog_skeleton) */
 | |
| 	struct bpf_prog_skeleton *progs;
 | |
| 
 | |
| 	int var_cnt;
 | |
| 	int var_skel_sz; /* sizeof(struct bpf_var_skeleton) */
 | |
| 	struct bpf_var_skeleton *vars;
 | |
| };
 | |
| 
 | |
| LIBBPF_API int
 | |
| bpf_object__open_subskeleton(struct bpf_object_subskeleton *s);
 | |
| LIBBPF_API void
 | |
| bpf_object__destroy_subskeleton(struct bpf_object_subskeleton *s);
 | |
| 
 | |
| struct gen_loader_opts {
 | |
| 	size_t sz; /* size of this struct, for forward/backward compatibility */
 | |
| 	const char *data;
 | |
| 	const char *insns;
 | |
| 	__u32 data_sz;
 | |
| 	__u32 insns_sz;
 | |
| };
 | |
| 
 | |
| #define gen_loader_opts__last_field insns_sz
 | |
| LIBBPF_API int bpf_object__gen_loader(struct bpf_object *obj,
 | |
| 				      struct gen_loader_opts *opts);
 | |
| 
 | |
| enum libbpf_tristate {
 | |
| 	TRI_NO = 0,
 | |
| 	TRI_YES = 1,
 | |
| 	TRI_MODULE = 2,
 | |
| };
 | |
| 
 | |
| struct bpf_linker_opts {
 | |
| 	/* size of this struct, for forward/backward compatibility */
 | |
| 	size_t sz;
 | |
| };
 | |
| #define bpf_linker_opts__last_field sz
 | |
| 
 | |
| struct bpf_linker_file_opts {
 | |
| 	/* size of this struct, for forward/backward compatibility */
 | |
| 	size_t sz;
 | |
| };
 | |
| #define bpf_linker_file_opts__last_field sz
 | |
| 
 | |
| struct bpf_linker;
 | |
| 
 | |
| LIBBPF_API struct bpf_linker *bpf_linker__new(const char *filename, struct bpf_linker_opts *opts);
 | |
| LIBBPF_API int bpf_linker__add_file(struct bpf_linker *linker,
 | |
| 				    const char *filename,
 | |
| 				    const struct bpf_linker_file_opts *opts);
 | |
| LIBBPF_API int bpf_linker__finalize(struct bpf_linker *linker);
 | |
| LIBBPF_API void bpf_linker__free(struct bpf_linker *linker);
 | |
| 
 | |
| /*
 | |
|  * Custom handling of BPF program's SEC() definitions
 | |
|  */
 | |
| 
 | |
| struct bpf_prog_load_opts; /* defined in bpf.h */
 | |
| 
 | |
| /* Called during bpf_object__open() for each recognized BPF program. Callback
 | |
|  * can use various bpf_program__set_*() setters to adjust whatever properties
 | |
|  * are necessary.
 | |
|  */
 | |
| typedef int (*libbpf_prog_setup_fn_t)(struct bpf_program *prog, long cookie);
 | |
| 
 | |
| /* Called right before libbpf performs bpf_prog_load() to load BPF program
 | |
|  * into the kernel. Callback can adjust opts as necessary.
 | |
|  */
 | |
| typedef int (*libbpf_prog_prepare_load_fn_t)(struct bpf_program *prog,
 | |
| 					     struct bpf_prog_load_opts *opts, long cookie);
 | |
| 
 | |
| /* Called during skeleton attach or through bpf_program__attach(). If
 | |
|  * auto-attach is not supported, callback should return 0 and set link to
 | |
|  * NULL (it's not considered an error during skeleton attach, but it will be
 | |
|  * an error for bpf_program__attach() calls). On error, error should be
 | |
|  * returned directly and link set to NULL. On success, return 0 and set link
 | |
|  * to a valid struct bpf_link.
 | |
|  */
 | |
| typedef int (*libbpf_prog_attach_fn_t)(const struct bpf_program *prog, long cookie,
 | |
| 				       struct bpf_link **link);
 | |
| 
 | |
| struct libbpf_prog_handler_opts {
 | |
| 	/* size of this struct, for forward/backward compatibility */
 | |
| 	size_t sz;
 | |
| 	/* User-provided value that is passed to prog_setup_fn,
 | |
| 	 * prog_prepare_load_fn, and prog_attach_fn callbacks. Allows user to
 | |
| 	 * register one set of callbacks for multiple SEC() definitions and
 | |
| 	 * still be able to distinguish them, if necessary. For example,
 | |
| 	 * libbpf itself is using this to pass necessary flags (e.g.,
 | |
| 	 * sleepable flag) to a common internal SEC() handler.
 | |
| 	 */
 | |
| 	long cookie;
 | |
| 	/* BPF program initialization callback (see libbpf_prog_setup_fn_t).
 | |
| 	 * Callback is optional, pass NULL if it's not necessary.
 | |
| 	 */
 | |
| 	libbpf_prog_setup_fn_t prog_setup_fn;
 | |
| 	/* BPF program loading callback (see libbpf_prog_prepare_load_fn_t).
 | |
| 	 * Callback is optional, pass NULL if it's not necessary.
 | |
| 	 */
 | |
| 	libbpf_prog_prepare_load_fn_t prog_prepare_load_fn;
 | |
| 	/* BPF program attach callback (see libbpf_prog_attach_fn_t).
 | |
| 	 * Callback is optional, pass NULL if it's not necessary.
 | |
| 	 */
 | |
| 	libbpf_prog_attach_fn_t prog_attach_fn;
 | |
| };
 | |
| #define libbpf_prog_handler_opts__last_field prog_attach_fn
 | |
| 
 | |
| /**
 | |
|  * @brief **libbpf_register_prog_handler()** registers a custom BPF program
 | |
|  * SEC() handler.
 | |
|  * @param sec section prefix for which custom handler is registered
 | |
|  * @param prog_type BPF program type associated with specified section
 | |
|  * @param exp_attach_type Expected BPF attach type associated with specified section
 | |
|  * @param opts optional cookie, callbacks, and other extra options
 | |
|  * @return Non-negative handler ID is returned on success. This handler ID has
 | |
|  * to be passed to *libbpf_unregister_prog_handler()* to unregister such
 | |
|  * custom handler. Negative error code is returned on error.
 | |
|  *
 | |
|  * *sec* defines which SEC() definitions are handled by this custom handler
 | |
|  * registration. *sec* can have few different forms:
 | |
|  *   - if *sec* is just a plain string (e.g., "abc"), it will match only
 | |
|  *   SEC("abc"). If BPF program specifies SEC("abc/whatever") it will result
 | |
|  *   in an error;
 | |
|  *   - if *sec* is of the form "abc/", proper SEC() form is
 | |
|  *   SEC("abc/something"), where acceptable "something" should be checked by
 | |
|  *   *prog_init_fn* callback, if there are additional restrictions;
 | |
|  *   - if *sec* is of the form "abc+", it will successfully match both
 | |
|  *   SEC("abc") and SEC("abc/whatever") forms;
 | |
|  *   - if *sec* is NULL, custom handler is registered for any BPF program that
 | |
|  *   doesn't match any of the registered (custom or libbpf's own) SEC()
 | |
|  *   handlers. There could be only one such generic custom handler registered
 | |
|  *   at any given time.
 | |
|  *
 | |
|  * All custom handlers (except the one with *sec* == NULL) are processed
 | |
|  * before libbpf's own SEC() handlers. It is allowed to "override" libbpf's
 | |
|  * SEC() handlers by registering custom ones for the same section prefix
 | |
|  * (i.e., it's possible to have custom SEC("perf_event/LLC-load-misses")
 | |
|  * handler).
 | |
|  *
 | |
|  * Note, like much of global libbpf APIs (e.g., libbpf_set_print(),
 | |
|  * libbpf_set_strict_mode(), etc)) these APIs are not thread-safe. User needs
 | |
|  * to ensure synchronization if there is a risk of running this API from
 | |
|  * multiple threads simultaneously.
 | |
|  */
 | |
| LIBBPF_API int libbpf_register_prog_handler(const char *sec,
 | |
| 					    enum bpf_prog_type prog_type,
 | |
| 					    enum bpf_attach_type exp_attach_type,
 | |
| 					    const struct libbpf_prog_handler_opts *opts);
 | |
| /**
 | |
|  * @brief *libbpf_unregister_prog_handler()* unregisters previously registered
 | |
|  * custom BPF program SEC() handler.
 | |
|  * @param handler_id handler ID returned by *libbpf_register_prog_handler()*
 | |
|  * after successful registration
 | |
|  * @return 0 on success, negative error code if handler isn't found
 | |
|  *
 | |
|  * Note, like much of global libbpf APIs (e.g., libbpf_set_print(),
 | |
|  * libbpf_set_strict_mode(), etc)) these APIs are not thread-safe. User needs
 | |
|  * to ensure synchronization if there is a risk of running this API from
 | |
|  * multiple threads simultaneously.
 | |
|  */
 | |
| LIBBPF_API int libbpf_unregister_prog_handler(int handler_id);
 | |
| 
 | |
| #ifdef __cplusplus
 | |
| } /* extern "C" */
 | |
| #endif
 | |
| 
 | |
| #endif /* __LIBBPF_LIBBPF_H */
 |