1/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
  2/* Copyright (c) 2021 Facebook */
  3#ifndef __SKEL_INTERNAL_H
  4#define __SKEL_INTERNAL_H
  5
  6#include <unistd.h>
  7#include <sys/syscall.h>
  8#include <sys/mman.h>
  9
 10/* This file is a base header for auto-generated *.lskel.h files.
 11 * Its contents will change and may become part of auto-generation in the future.
 12 *
 13 * The layout of bpf_[map|prog]_desc and bpf_loader_ctx is feature dependent
 14 * and will change from one version of libbpf to another and features
 15 * requested during loader program generation.
 16 */
 17struct bpf_map_desc {
 18	union {
 19		/* input for the loader prog */
 20		struct {
 21			__aligned_u64 initial_value;
 22			__u32 max_entries;
 23		};
 24		/* output of the loader prog */
 25		struct {
 26			int map_fd;
 27		};
 28	};
 29};
 30struct bpf_prog_desc {
 31	int prog_fd;
 32};
 33
 34struct bpf_loader_ctx {
 35	size_t sz;
 36	__u32 log_level;
 37	__u32 log_size;
 38	__u64 log_buf;
 39};
 40
 41struct bpf_load_and_run_opts {
 42	struct bpf_loader_ctx *ctx;
 43	const void *data;
 44	const void *insns;
 45	__u32 data_sz;
 46	__u32 insns_sz;
 47	const char *errstr;
 48};
 49
 50static inline int skel_sys_bpf(enum bpf_cmd cmd, union bpf_attr *attr,
 51			  unsigned int size)
 52{
 53	return syscall(__NR_bpf, cmd, attr, size);
 54}
 55
 56static inline int skel_closenz(int fd)
 57{
 58	if (fd > 0)
 59		return close(fd);
 60	return -EINVAL;
 61}
 62
 63static inline int bpf_load_and_run(struct bpf_load_and_run_opts *opts)
 64{
 65	int map_fd = -1, prog_fd = -1, key = 0, err;
 66	union bpf_attr attr;
 67
 68	map_fd = bpf_create_map_name(BPF_MAP_TYPE_ARRAY, "__loader.map", 4,
 69				     opts->data_sz, 1, 0);
 70	if (map_fd < 0) {
 71		opts->errstr = "failed to create loader map";
 72		err = -errno;
 73		goto out;
 74	}
 75
 76	err = bpf_map_update_elem(map_fd, &key, opts->data, 0);
 77	if (err < 0) {
 78		opts->errstr = "failed to update loader map";
 79		err = -errno;
 80		goto out;
 81	}
 82
 83	memset(&attr, 0, sizeof(attr));
 84	attr.prog_type = BPF_PROG_TYPE_SYSCALL;
 85	attr.insns = (long) opts->insns;
 86	attr.insn_cnt = opts->insns_sz / sizeof(struct bpf_insn);
 87	attr.license = (long) "Dual BSD/GPL";
 88	memcpy(attr.prog_name, "__loader.prog", sizeof("__loader.prog"));
 89	attr.fd_array = (long) &map_fd;
 90	attr.log_level = opts->ctx->log_level;
 91	attr.log_size = opts->ctx->log_size;
 92	attr.log_buf = opts->ctx->log_buf;
 93	attr.prog_flags = BPF_F_SLEEPABLE;
 94	prog_fd = skel_sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr));
 95	if (prog_fd < 0) {
 96		opts->errstr = "failed to load loader prog";
 97		err = -errno;
 98		goto out;
 99	}
100
101	memset(&attr, 0, sizeof(attr));
102	attr.test.prog_fd = prog_fd;
103	attr.test.ctx_in = (long) opts->ctx;
104	attr.test.ctx_size_in = opts->ctx->sz;
105	err = skel_sys_bpf(BPF_PROG_RUN, &attr, sizeof(attr));
106	if (err < 0 || (int)attr.test.retval < 0) {
107		opts->errstr = "failed to execute loader prog";
108		if (err < 0)
109			err = -errno;
110		else
111			err = (int)attr.test.retval;
112		goto out;
113	}
114	err = 0;
115out:
116	if (map_fd >= 0)
117		close(map_fd);
118	if (prog_fd >= 0)
119		close(prog_fd);
120	return err;
121}
122
123#endif