LXR linux/tools/bpf/bpftool/skeleton/pid

   1// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
   2/* Copyright (c) 2020 Facebook */
   3#include <vmlinux.h>
   4#include <bpf/bpf_helpers.h>
   5#include <bpf/bpf_core_read.h>
   6#include <bpf/bpf_tracing.h>
   7#include "pid_iter.h"
   8
   9/* keep in sync with the definition in main.h */
  10enum bpf_obj_type {
  11        BPF_OBJ_UNKNOWN,
  12        BPF_OBJ_PROG,
  13        BPF_OBJ_MAP,
  14        BPF_OBJ_LINK,
  15        BPF_OBJ_BTF,
  16};
  17
  18extern const void bpf_link_fops __ksym;
  19extern const void bpf_map_fops __ksym;
  20extern const void bpf_prog_fops __ksym;
  21extern const void btf_fops __ksym;
  22
  23const volatile enum bpf_obj_type obj_type = BPF_OBJ_UNKNOWN;
  24
  25static __always_inline __u32 get_obj_id(void *ent, enum bpf_obj_type type)
  26{
  27        switch (type) {
  28        case BPF_OBJ_PROG:
  29                return BPF_CORE_READ((struct bpf_prog *)ent, aux, id);
  30        case BPF_OBJ_MAP:
  31                return BPF_CORE_READ((struct bpf_map *)ent, id);
  32        case BPF_OBJ_BTF:
  33                return BPF_CORE_READ((struct btf *)ent, id);
  34        case BPF_OBJ_LINK:
  35                return BPF_CORE_READ((struct bpf_link *)ent, id);
  36        default:
  37                return 0;
  38        }
  39}
  40
  41SEC("iter/task_file")
  42int iter(struct bpf_iter__task_file *ctx)
  43{
  44        struct file *file = ctx->file;
  45        struct task_struct *task = ctx->task;
  46        struct pid_iter_entry e;
  47        const void *fops;
  48
  49        if (!file || !task)
  50                return 0;
  51
  52        switch (obj_type) {
  53        case BPF_OBJ_PROG:
  54                fops = &bpf_prog_fops;
  55                break;
  56        case BPF_OBJ_MAP:
  57                fops = &bpf_map_fops;
  58                break;
  59        case BPF_OBJ_BTF:
  60                fops = &btf_fops;
  61                break;
  62        case BPF_OBJ_LINK:
  63                fops = &bpf_link_fops;
  64                break;
  65        default:
  66                return 0;
  67        }
  68
  69        if (file->f_op != fops)
  70                return 0;
  71
  72        e.pid = task->tgid;
  73        e.id = get_obj_id(file->private_data, obj_type);
  74        bpf_probe_read_kernel(&e.comm, sizeof(e.comm),
  75                              task->group_leader->comm);
  76        bpf_seq_write(ctx->meta->seq, &e, sizeof(e));
  77
  78        return 0;
  79}
  80
  81char LICENSE[] SEC("license") = "Dual BSD/GPL";
  82