From b88bb292821fd7742604ec4e280acebd9a049f62 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 12:36:22 +0200 Subject: Adding upstream version 3.0.5. Signed-off-by: Daniel Baumann --- src/contrib/libbpf/bpf/libbpf.h | 637 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 637 insertions(+) create mode 100644 src/contrib/libbpf/bpf/libbpf.h (limited to 'src/contrib/libbpf/bpf/libbpf.h') diff --git a/src/contrib/libbpf/bpf/libbpf.h b/src/contrib/libbpf/bpf/libbpf.h new file mode 100644 index 0000000..0dbf4bf --- /dev/null +++ b/src/contrib/libbpf/bpf/libbpf.h @@ -0,0 +1,637 @@ +/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ + +/* + * Common eBPF ELF object loading operations. + * + * Copyright (C) 2013-2015 Alexei Starovoitov + * Copyright (C) 2015 Wang Nan + * Copyright (C) 2015 Huawei Inc. + */ +#ifndef __LIBBPF_LIBBPF_H +#define __LIBBPF_LIBBPF_H + +#include +#include +#include +#include +#include // for size_t +#include + +#ifdef __cplusplus +extern "C" { +#endif + +#ifndef LIBBPF_API +#define LIBBPF_API __attribute__((visibility("default"))) +#endif + +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); + +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_attr { + const char *file; + enum bpf_prog_type prog_type; +}; + +/* Helper macro to declare and initialize libbpf options struct + * + * This dance with uninitialized declaration, followed by memset to zero, + * followed by assignment using compound literal syntax is done to preserve + * ability to use a nice struct field initialization syntax and **hopefully** + * have all the padding bytes initialized to zero. It's not guaranteed though, + * when copying literal, that compiler won't copy garbage in literal's padding + * bytes, but that's the best way I've found and it seems to work in practice. + * + * Macro declares opts struct of given type and name, zero-initializes, + * including any extra padding, it with memset() and then assigns initial + * values provided by users in struct initializer-syntax as varargs. + */ +#define DECLARE_LIBBPF_OPTS(TYPE, NAME, ...) \ + struct TYPE NAME = ({ \ + memset(&NAME, 0, sizeof(struct TYPE)); \ + (struct TYPE) { \ + .sz = sizeof(struct TYPE), \ + __VA_ARGS__ \ + }; \ + }) + +struct bpf_object_open_opts { + /* size of this struct, for forward/backward compatiblity */ + 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 "-" name; + */ + const char *object_name; + /* parse map definitions non-strictly, allowing extra attributes/data */ + bool relaxed_maps; + /* process CO-RE relocations non-strictly, allowing them to fail */ + bool relaxed_core_relocs; + /* 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 attach_prog_fd; +}; +#define bpf_object_open_opts__last_field attach_prog_fd + +LIBBPF_API struct bpf_object *bpf_object__open(const char *path); +LIBBPF_API struct bpf_object * +bpf_object__open_file(const char *path, struct bpf_object_open_opts *opts); +LIBBPF_API struct bpf_object * +bpf_object__open_mem(const void *obj_buf, size_t obj_buf_sz, + struct bpf_object_open_opts *opts); + +/* deprecated bpf_object__open variants */ +LIBBPF_API struct bpf_object * +bpf_object__open_buffer(const void *obj_buf, size_t obj_buf_sz, + const char *name); +LIBBPF_API struct bpf_object * +bpf_object__open_xattr(struct bpf_object_open_attr *attr); + +int bpf_object__section_size(const struct bpf_object *obj, const char *name, + __u32 *size); +int bpf_object__variable_offset(const struct bpf_object *obj, const char *name, + __u32 *off); + +enum libbpf_pin_type { + LIBBPF_PIN_NONE, + /* PIN_BY_NAME: pin maps by name (in /sys/fs/bpf by default) */ + LIBBPF_PIN_BY_NAME, +}; + +/* 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 void bpf_object__close(struct bpf_object *object); + +struct bpf_object_load_attr { + struct bpf_object *obj; + int log_level; + const char *target_btf_path; +}; + +/* Load/unload object into/from kernel */ +LIBBPF_API int bpf_object__load(struct bpf_object *obj); +LIBBPF_API int bpf_object__load_xattr(struct bpf_object_load_attr *attr); +LIBBPF_API int bpf_object__unload(struct bpf_object *obj); +LIBBPF_API const char *bpf_object__name(const struct bpf_object *obj); +LIBBPF_API unsigned int bpf_object__kversion(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_title(const struct bpf_object *obj, + const char *title); + +LIBBPF_API struct bpf_object *bpf_object__next(struct bpf_object *prev); +#define bpf_object__for_each_safe(pos, tmp) \ + for ((pos) = bpf_object__next(NULL), \ + (tmp) = bpf_object__next(pos); \ + (pos) != NULL; \ + (pos) = (tmp), (tmp) = bpf_object__next(tmp)) + +typedef void (*bpf_object_clear_priv_t)(struct bpf_object *, void *); +LIBBPF_API int bpf_object__set_priv(struct bpf_object *obj, void *priv, + bpf_object_clear_priv_t clear_priv); +LIBBPF_API void *bpf_object__priv(const struct bpf_object *prog); + +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_program__next(struct bpf_program *prog, + const struct bpf_object *obj); + +#define bpf_object__for_each_program(pos, obj) \ + for ((pos) = bpf_program__next(NULL, (obj)); \ + (pos) != NULL; \ + (pos) = bpf_program__next((pos), (obj))) + +LIBBPF_API struct bpf_program *bpf_program__prev(struct bpf_program *prog, + const struct bpf_object *obj); + +typedef void (*bpf_program_clear_priv_t)(struct bpf_program *, void *); + +LIBBPF_API int bpf_program__set_priv(struct bpf_program *prog, void *priv, + bpf_program_clear_priv_t clear_priv); + +LIBBPF_API void *bpf_program__priv(const struct bpf_program *prog); +LIBBPF_API void bpf_program__set_ifindex(struct bpf_program *prog, + __u32 ifindex); + +LIBBPF_API const char *bpf_program__title(const struct bpf_program *prog, + bool needs_copy); + +/* returns program size in bytes */ +LIBBPF_API size_t bpf_program__size(const struct bpf_program *prog); + +LIBBPF_API int bpf_program__load(struct bpf_program *prog, char *license, + __u32 kern_version); +LIBBPF_API int bpf_program__fd(const struct bpf_program *prog); +LIBBPF_API int bpf_program__pin_instance(struct bpf_program *prog, + const char *path, + int instance); +LIBBPF_API int bpf_program__unpin_instance(struct bpf_program *prog, + const char *path, + int instance); +LIBBPF_API int bpf_program__pin(struct bpf_program *prog, const char *path); +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 int bpf_link__destroy(struct bpf_link *link); + +LIBBPF_API struct bpf_link * +bpf_program__attach_perf_event(struct bpf_program *prog, int pfd); +LIBBPF_API struct bpf_link * +bpf_program__attach_kprobe(struct bpf_program *prog, bool retprobe, + const char *func_name); +LIBBPF_API struct bpf_link * +bpf_program__attach_uprobe(struct bpf_program *prog, bool retprobe, + pid_t pid, const char *binary_path, + size_t func_offset); +LIBBPF_API struct bpf_link * +bpf_program__attach_tracepoint(struct bpf_program *prog, + const char *tp_category, + const char *tp_name); +LIBBPF_API struct bpf_link * +bpf_program__attach_raw_tracepoint(struct bpf_program *prog, + const char *tp_name); + +LIBBPF_API struct bpf_link * +bpf_program__attach_trace(struct bpf_program *prog); +struct bpf_insn; + +/* + * Libbpf allows callers to adjust BPF programs before being loaded + * into kernel. One program in an object file can be transformed into + * multiple variants to be attached to different hooks. + * + * bpf_program_prep_t, bpf_program__set_prep and bpf_program__nth_fd + * form an API for this purpose. + * + * - bpf_program_prep_t: + * Defines a 'preprocessor', which is a caller defined function + * passed to libbpf through bpf_program__set_prep(), and will be + * called before program is loaded. The processor should adjust + * the program one time for each instance according to the instance id + * passed to it. + * + * - bpf_program__set_prep: + * Attaches a preprocessor to a BPF program. The number of instances + * that should be created is also passed through this function. + * + * - bpf_program__nth_fd: + * After the program is loaded, get resulting FD of a given instance + * of the BPF program. + * + * If bpf_program__set_prep() is not used, the program would be loaded + * without adjustment during bpf_object__load(). The program has only + * one instance. In this case bpf_program__fd(prog) is equal to + * bpf_program__nth_fd(prog, 0). + */ + +struct bpf_prog_prep_result { + /* + * If not NULL, load new instruction array. + * If set to NULL, don't load this instance. + */ + struct bpf_insn *new_insn_ptr; + int new_insn_cnt; + + /* If not NULL, result FD is written to it. */ + int *pfd; +}; + +/* + * Parameters of bpf_program_prep_t: + * - prog: The bpf_program being loaded. + * - n: Index of instance being generated. + * - insns: BPF instructions array. + * - insns_cnt:Number of instructions in insns. + * - res: Output parameter, result of transformation. + * + * Return value: + * - Zero: pre-processing success. + * - Non-zero: pre-processing error, stop loading. + */ +typedef int (*bpf_program_prep_t)(struct bpf_program *prog, int n, + struct bpf_insn *insns, int insns_cnt, + struct bpf_prog_prep_result *res); + +LIBBPF_API int bpf_program__set_prep(struct bpf_program *prog, int nr_instance, + bpf_program_prep_t prep); + +LIBBPF_API int bpf_program__nth_fd(const struct bpf_program *prog, int n); + +/* + * Adjust type of BPF program. Default is kprobe. + */ +LIBBPF_API int bpf_program__set_socket_filter(struct bpf_program *prog); +LIBBPF_API int bpf_program__set_tracepoint(struct bpf_program *prog); +LIBBPF_API int bpf_program__set_raw_tracepoint(struct bpf_program *prog); +LIBBPF_API int bpf_program__set_kprobe(struct bpf_program *prog); +LIBBPF_API int bpf_program__set_sched_cls(struct bpf_program *prog); +LIBBPF_API int bpf_program__set_sched_act(struct bpf_program *prog); +LIBBPF_API int bpf_program__set_xdp(struct bpf_program *prog); +LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog); +LIBBPF_API int bpf_program__set_tracing(struct bpf_program *prog); + +LIBBPF_API enum bpf_prog_type bpf_program__get_type(struct bpf_program *prog); +LIBBPF_API void bpf_program__set_type(struct bpf_program *prog, + enum bpf_prog_type type); + +LIBBPF_API enum bpf_attach_type +bpf_program__get_expected_attach_type(struct bpf_program *prog); +LIBBPF_API void +bpf_program__set_expected_attach_type(struct bpf_program *prog, + enum bpf_attach_type type); + +LIBBPF_API bool bpf_program__is_socket_filter(const struct bpf_program *prog); +LIBBPF_API bool bpf_program__is_tracepoint(const struct bpf_program *prog); +LIBBPF_API bool bpf_program__is_raw_tracepoint(const struct bpf_program *prog); +LIBBPF_API bool bpf_program__is_kprobe(const struct bpf_program *prog); +LIBBPF_API bool bpf_program__is_sched_cls(const struct bpf_program *prog); +LIBBPF_API bool bpf_program__is_sched_act(const struct bpf_program *prog); +LIBBPF_API bool bpf_program__is_xdp(const struct bpf_program *prog); +LIBBPF_API bool bpf_program__is_perf_event(const struct bpf_program *prog); +LIBBPF_API bool bpf_program__is_tracing(const struct bpf_program *prog); + +/* + * No need for __attribute__((packed)), all members of 'bpf_map_def' + * are all aligned. In addition, using __attribute__((packed)) + * would trigger a -Wpacked warning message, and lead to an error + * if -Werror is set. + */ +struct bpf_map_def { + unsigned int type; + unsigned int key_size; + unsigned int value_size; + unsigned int max_entries; + unsigned int map_flags; +}; + +/* + * The 'struct bpf_map' in include/linux/bpf.h is internal to the kernel, + * so no need to worry about a name clash. + */ +struct bpf_map; +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); + +/* + * Get bpf_map through the offset of corresponding struct bpf_map_def + * in the BPF object file. + */ +LIBBPF_API struct bpf_map * +bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset); + +LIBBPF_API struct bpf_map * +bpf_map__next(const struct bpf_map *map, const struct bpf_object *obj); +#define bpf_object__for_each_map(pos, obj) \ + for ((pos) = bpf_map__next(NULL, (obj)); \ + (pos) != NULL; \ + (pos) = bpf_map__next((pos), (obj))) +#define bpf_map__for_each bpf_object__for_each_map + +LIBBPF_API struct bpf_map * +bpf_map__prev(const struct bpf_map *map, const struct bpf_object *obj); + +LIBBPF_API int bpf_map__fd(const struct bpf_map *map); +LIBBPF_API const struct bpf_map_def *bpf_map__def(const struct bpf_map *map); +LIBBPF_API const char *bpf_map__name(const struct bpf_map *map); +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); + +typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *); +LIBBPF_API int bpf_map__set_priv(struct bpf_map *map, void *priv, + bpf_map_clear_priv_t clear_priv); +LIBBPF_API void *bpf_map__priv(const struct bpf_map *map); +LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd); +LIBBPF_API int bpf_map__resize(struct bpf_map *map, __u32 max_entries); +LIBBPF_API bool bpf_map__is_offload_neutral(const struct bpf_map *map); +LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map); +LIBBPF_API void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex); +LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path); +LIBBPF_API const char *bpf_map__get_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 long libbpf_get_error(const void *ptr); + +struct bpf_prog_load_attr { + const char *file; + enum bpf_prog_type prog_type; + enum bpf_attach_type expected_attach_type; + int ifindex; + int log_level; + int prog_flags; +}; + +LIBBPF_API int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr, + struct bpf_object **pobj, int *prog_fd); +LIBBPF_API int bpf_prog_load(const char *file, enum bpf_prog_type type, + struct bpf_object **pobj, int *prog_fd); + +struct xdp_link_info { + __u32 prog_id; + __u32 drv_prog_id; + __u32 hw_prog_id; + __u32 skb_prog_id; + __u8 attach_mode; +}; + +LIBBPF_API int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags); +LIBBPF_API int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags); +LIBBPF_API int bpf_get_link_xdp_info(int ifindex, struct xdp_link_info *info, + size_t info_size, __u32 flags); + +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 { + /* if specified, sample_cb is called for each sample */ + perf_buffer_sample_fn sample_cb; + /* if specified, lost_cb is called for each batch of lost samples */ + perf_buffer_lost_fn lost_cb; + /* ctx is provided to sample_cb and lost_cb */ + void *ctx; +}; + +LIBBPF_API struct perf_buffer * +perf_buffer__new(int map_fd, size_t page_cnt, + 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 { + /* perf event attrs passed directly into perf_event_open() */ + struct perf_event_attr *attr; + /* raw event callback */ + perf_buffer_event_fn event_cb; + /* ctx is provided to event_cb */ + void *ctx; + /* 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; +}; + +LIBBPF_API struct perf_buffer * +perf_buffer__new_raw(int map_fd, size_t page_cnt, + const struct perf_buffer_raw_opts *opts); + +LIBBPF_API void perf_buffer__free(struct perf_buffer *pb); +LIBBPF_API int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms); + +typedef enum bpf_perf_event_ret + (*bpf_perf_event_print_t)(struct perf_event_header *hdr, + void *private_data); +LIBBPF_API enum bpf_perf_event_ret +bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size, + void **copy_mem, size_t *copy_size, + bpf_perf_event_print_t fn, void *private_data); + +struct nlattr; +typedef int (*libbpf_dump_nlmsg_t)(void *cookie, void *msg, struct nlattr **tb); +int libbpf_netlink_open(unsigned int *nl_pid); +int libbpf_nl_get_link(int sock, unsigned int nl_pid, + libbpf_dump_nlmsg_t dump_link_nlmsg, void *cookie); +int libbpf_nl_get_class(int sock, unsigned int nl_pid, int ifindex, + libbpf_dump_nlmsg_t dump_class_nlmsg, void *cookie); +int libbpf_nl_get_qdisc(int sock, unsigned int nl_pid, int ifindex, + libbpf_dump_nlmsg_t dump_qdisc_nlmsg, void *cookie); +int libbpf_nl_get_filter(int sock, unsigned int nl_pid, int ifindex, int handle, + libbpf_dump_nlmsg_t dump_filter_nlmsg, void *cookie); + +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(). + */ +LIBBPF_API bool bpf_probe_prog_type(enum bpf_prog_type prog_type, + __u32 ifindex); +LIBBPF_API bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex); +LIBBPF_API bool bpf_probe_helper(enum bpf_func_id id, + enum bpf_prog_type prog_type, __u32 ifindex); + +/* + * Get bpf_prog_info in continuous memory + * + * struct bpf_prog_info has multiple arrays. The user has option to choose + * arrays to fetch from kernel. The following APIs provide an uniform way to + * fetch these data. All arrays in bpf_prog_info are stored in a single + * continuous memory region. This makes it easy to store the info in a + * file. + * + * Before writing bpf_prog_info_linear to files, it is necessary to + * translate pointers in bpf_prog_info to offsets. Helper functions + * bpf_program__bpil_addr_to_offs() and bpf_program__bpil_offs_to_addr() + * are introduced to switch between pointers and offsets. + * + * Examples: + * # To fetch map_ids and prog_tags: + * __u64 arrays = (1UL << BPF_PROG_INFO_MAP_IDS) | + * (1UL << BPF_PROG_INFO_PROG_TAGS); + * struct bpf_prog_info_linear *info_linear = + * bpf_program__get_prog_info_linear(fd, arrays); + * + * # To save data in file + * bpf_program__bpil_addr_to_offs(info_linear); + * write(f, info_linear, sizeof(*info_linear) + info_linear->data_len); + * + * # To read data from file + * read(f, info_linear, ); + * bpf_program__bpil_offs_to_addr(info_linear); + */ +enum bpf_prog_info_array { + BPF_PROG_INFO_FIRST_ARRAY = 0, + BPF_PROG_INFO_JITED_INSNS = 0, + BPF_PROG_INFO_XLATED_INSNS, + BPF_PROG_INFO_MAP_IDS, + BPF_PROG_INFO_JITED_KSYMS, + BPF_PROG_INFO_JITED_FUNC_LENS, + BPF_PROG_INFO_FUNC_INFO, + BPF_PROG_INFO_LINE_INFO, + BPF_PROG_INFO_JITED_LINE_INFO, + BPF_PROG_INFO_PROG_TAGS, + BPF_PROG_INFO_LAST_ARRAY, +}; + +struct bpf_prog_info_linear { + /* size of struct bpf_prog_info, when the tool is compiled */ + __u32 info_len; + /* total bytes allocated for data, round up to 8 bytes */ + __u32 data_len; + /* which arrays are included in data */ + __u64 arrays; + struct bpf_prog_info info; + __u8 data[]; +}; + +LIBBPF_API struct bpf_prog_info_linear * +bpf_program__get_prog_info_linear(int fd, __u64 arrays); + +LIBBPF_API void +bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear); + +LIBBPF_API void +bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear); + +/* + * A helper function to get the number of possible CPUs before looking up + * per-CPU maps. Negative errno is returned 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); + +#ifdef __cplusplus +} /* extern "C" */ +#endif + +#endif /* __LIBBPF_LIBBPF_H */ -- cgit v1.2.3