bpf-loader.h

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/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Copyright (C) 2015, Wang Nan <wangnan0@huawei.com>
 * Copyright (C) 2015, Huawei Inc.
 */
#ifndef __BPF_LOADER_H
#define __BPF_LOADER_H

#include <linux/compiler.h>
#include <linux/err.h>
#include <string.h>
#include <bpf/libbpf.h>
#include "probe-event.h"
#include "evlist.h"
#include "debug.h"

enum bpf_loader_errno {
    __BPF_LOADER_ERRNO__START = __LIBBPF_ERRNO__START - 100,
    /* Invalid config string */
    BPF_LOADER_ERRNO__CONFIG = __BPF_LOADER_ERRNO__START,
    BPF_LOADER_ERRNO__GROUP,    /* Invalid group name */
    BPF_LOADER_ERRNO__EVENTNAME,    /* Event name is missing */
    BPF_LOADER_ERRNO__INTERNAL, /* BPF loader internal error */
    BPF_LOADER_ERRNO__COMPILE,  /* Error when compiling BPF scriptlet */
    BPF_LOADER_ERRNO__PROGCONF_TERM,/* Invalid program config term in config string */
    BPF_LOADER_ERRNO__PROLOGUE, /* Failed to generate prologue */
    BPF_LOADER_ERRNO__PROLOGUE2BIG, /* Prologue too big for program */
    BPF_LOADER_ERRNO__PROLOGUEOOB,  /* Offset out of bound for prologue */
    BPF_LOADER_ERRNO__OBJCONF_OPT,  /* Invalid object config option */
    BPF_LOADER_ERRNO__OBJCONF_CONF, /* Config value not set (lost '=')) */
    BPF_LOADER_ERRNO__OBJCONF_MAP_OPT,  /* Invalid object map config option */
    BPF_LOADER_ERRNO__OBJCONF_MAP_NOTEXIST, /* Target map not exist */
    BPF_LOADER_ERRNO__OBJCONF_MAP_VALUE,    /* Incorrect value type for map */
    BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE, /* Incorrect map type */
    BPF_LOADER_ERRNO__OBJCONF_MAP_KEYSIZE,  /* Incorrect map key size */
    BPF_LOADER_ERRNO__OBJCONF_MAP_VALUESIZE,/* Incorrect map value size */
    BPF_LOADER_ERRNO__OBJCONF_MAP_NOEVT,    /* Event not found for map setting */
    BPF_LOADER_ERRNO__OBJCONF_MAP_MAPSIZE,  /* Invalid map size for event setting */
    BPF_LOADER_ERRNO__OBJCONF_MAP_EVTDIM,   /* Event dimension too large */
    BPF_LOADER_ERRNO__OBJCONF_MAP_EVTINH,   /* Doesn't support inherit event */
    BPF_LOADER_ERRNO__OBJCONF_MAP_EVTTYPE,  /* Wrong event type for map */
    BPF_LOADER_ERRNO__OBJCONF_MAP_IDX2BIG,  /* Index too large */
    __BPF_LOADER_ERRNO__END,
};

struct bpf_object;
struct parse_events_term;
#define PERF_BPF_PROBE_GROUP "perf_bpf_probe"

typedef int (*bpf_prog_iter_callback_t)(const char *group, const char *event,
                    int fd, void *arg);

#ifdef HAVE_LIBBPF_SUPPORT
struct bpf_object *bpf__prepare_load(const char *filename, bool source);
int bpf__strerror_prepare_load(const char *filename, bool source,
                   int err, char *buf, size_t size);

struct bpf_object *bpf__prepare_load_buffer(void *obj_buf, size_t obj_buf_sz,
                        const char *name);

void bpf__clear(void);

int bpf__probe(struct bpf_object *obj);
int bpf__unprobe(struct bpf_object *obj);
int bpf__strerror_probe(struct bpf_object *obj, int err,
            char *buf, size_t size);

int bpf__load(struct bpf_object *obj);
int bpf__strerror_load(struct bpf_object *obj, int err,
               char *buf, size_t size);
int bpf__foreach_event(struct bpf_object *obj,
               bpf_prog_iter_callback_t func, void *arg);

int bpf__config_obj(struct bpf_object *obj, struct parse_events_term *term,
            struct perf_evlist *evlist, int *error_pos);
int bpf__strerror_config_obj(struct bpf_object *obj,
                 struct parse_events_term *term,
                 struct perf_evlist *evlist,
                 int *error_pos, int err, char *buf,
                 size_t size);
int bpf__apply_obj_config(void);
int bpf__strerror_apply_obj_config(int err, char *buf, size_t size);

int bpf__setup_stdout(struct perf_evlist *evlist);
int bpf__strerror_setup_stdout(struct perf_evlist *evlist, int err,
                   char *buf, size_t size);

#else
#include <errno.h>

static inline struct bpf_object *
bpf__prepare_load(const char *filename __maybe_unused,
          bool source __maybe_unused)
{
    pr_debug("ERROR: eBPF object loading is disabled during compiling.\n");
    return ERR_PTR(-ENOTSUP);
}

static inline struct bpf_object *
bpf__prepare_load_buffer(void *obj_buf __maybe_unused,
                       size_t obj_buf_sz __maybe_unused)
{
    return ERR_PTR(-ENOTSUP);
}

static inline void bpf__clear(void) { }

static inline int bpf__probe(struct bpf_object *obj __maybe_unused) { return 0;}
static inline int bpf__unprobe(struct bpf_object *obj __maybe_unused) { return 0;}
static inline int bpf__load(struct bpf_object *obj __maybe_unused) { return 0; }

static inline int
bpf__foreach_event(struct bpf_object *obj __maybe_unused,
           bpf_prog_iter_callback_t func __maybe_unused,
           void *arg __maybe_unused)
{
    return 0;
}

static inline int
bpf__config_obj(struct bpf_object *obj __maybe_unused,
        struct parse_events_term *term __maybe_unused,
        struct perf_evlist *evlist __maybe_unused,
        int *error_pos __maybe_unused)
{
    return 0;
}

static inline int
bpf__apply_obj_config(void)
{
    return 0;
}

static inline int
bpf__setup_stdout(struct perf_evlist *evlist __maybe_unused)
{
    return 0;
}

static inline int
__bpf_strerror(char *buf, size_t size)
{
    if (!size)
        return 0;
    strncpy(buf,
        "ERROR: eBPF object loading is disabled during compiling.\n",
        size);
    buf[size - 1] = '\0';
    return 0;
}

static inline
int bpf__strerror_prepare_load(const char *filename __maybe_unused,
                   bool source __maybe_unused,
                   int err __maybe_unused,
                   char *buf, size_t size)
{
    return __bpf_strerror(buf, size);
}

static inline int
bpf__strerror_probe(struct bpf_object *obj __maybe_unused,
            int err __maybe_unused,
            char *buf, size_t size)
{
    return __bpf_strerror(buf, size);
}

static inline int bpf__strerror_load(struct bpf_object *obj __maybe_unused,
                     int err __maybe_unused,
                     char *buf, size_t size)
{
    return __bpf_strerror(buf, size);
}

static inline int
bpf__strerror_config_obj(struct bpf_object *obj __maybe_unused,
             struct parse_events_term *term __maybe_unused,
             struct perf_evlist *evlist __maybe_unused,
             int *error_pos __maybe_unused,
             int err __maybe_unused,
             char *buf, size_t size)
{
    return __bpf_strerror(buf, size);
}

static inline int
bpf__strerror_apply_obj_config(int err __maybe_unused,
                   char *buf, size_t size)
{
    return __bpf_strerror(buf, size);
}

static inline int
bpf__strerror_setup_stdout(struct perf_evlist *evlist __maybe_unused,
               int err __maybe_unused, char *buf,
               size_t size)
{
    return __bpf_strerror(buf, size);
}
#endif
#endif