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+/* 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);
+
+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 overriden
+ * 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;
+
+ size_t :0;
+};
+#define bpf_object_open_opts__last_field kernel_log_level
+
+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);
+
+/* Load/unload object into/from kernel */
+LIBBPF_API int bpf_object__load(struct bpf_object *obj);
+
+LIBBPF_API void bpf_object__close(struct bpf_object *object);
+
+/* pin_maps and unpin_maps can both be called with a NULL path, in which case
+ * they will use the pin_path attribute of each map (and ignore all maps that
+ * don't have a pin_path set).
+ */
+LIBBPF_API int bpf_object__pin_maps(struct bpf_object *obj, const char *path);
+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 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);
+
+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 paremeters, 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 compatiblity */
+ size_t sz;
+ /* custom user-provided value fetchable through bpf_get_attach_cookie() */
+ __u64 bpf_cookie;
+};
+#define bpf_perf_event_opts__last_field bpf_cookie
+
+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);
+
+struct bpf_kprobe_opts {
+ /* size of this struct, for forward/backward compatiblity */
+ 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;
+ size_t :0;
+};
+#define bpf_kprobe_opts__last_field retprobe
+
+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;
+ size_t :0;
+};
+
+#define bpf_kprobe_multi_opts__last_field retprobe
+
+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_ksyscall_opts {
+ /* size of this struct, for forward/backward compatiblity */
+ 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 compatiblity */
+ 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;
+ size_t :0;
+};
+#define bpf_uprobe_opts__last_field func_name
+
+/**
+ * @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 proccess 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 compatiblity */
+ 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);
+
+LIBBPF_API struct bpf_link *
+bpf_program__attach_raw_tracepoint(const struct bpf_program *prog,
+ const char *tp_name);
+
+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_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_map;
+
+LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(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__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/set map value size */
+LIBBPF_API __u32 bpf_map__value_size(const struct bpf_map *map);
+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 const void *bpf_map__initial_value(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);
+LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path);
+LIBBPF_API const char *bpf_map__pin_path(const struct bpf_map *map);
+LIBBPF_API bool bpf_map__is_pinned(const struct bpf_map *map);
+LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path);
+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 */
+ size_t :0;
+};
+#define bpf_xdp_query_opts__last_field attach_mode
+
+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 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 compatiblity */
+};
+
+#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__epoll_fd(const struct ring_buffer *rb);
+
+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;
+};
+#define perf_buffer_opts__last_field sz
+
+/**
+ * @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 managment 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 retreive
+ * @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_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 compatiblity */
+ 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 compatiblity */
+ size_t sz;
+};
+#define bpf_linker_opts__last_field sz
+
+struct bpf_linker_file_opts {
+ /* size of this struct, for forward/backward compatiblity */
+ 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 compatiblity */
+ 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 */