drivers/net/tap/tap_bpf.h

   1 /* SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
   2  * Copyright 2017 Mellanox Technologies, Ltd.
   3  */
   4
   5 #ifndef __TAP_BPF_H__
   6 #define __TAP_BPF_H__
   7
   8 #include <tap_autoconf.h>
   9
  10 /* Do not #include <linux/bpf.h> since eBPF must compile on different
  11  * distros which may include partial definitions for eBPF (while the
  12  * kernel itself may support eBPF). Instead define here all that is needed
  13  */
  14
  15 /* BPF_MAP_UPDATE_ELEM command flags */
  16 #define BPF_ANY 0 /* create a new element or update an existing */
  17
  18 /* BPF architecture instruction struct */
  19 struct bpf_insn {
  20         __u8    code;
  21         __u8    dst_reg:4;
  22         __u8    src_reg:4;
  23         __s16   off;
  24         __s32   imm; /* immediate value */
  25 };
  26
  27 /* BPF program types */
  28 enum bpf_prog_type {
  29         BPF_PROG_TYPE_UNSPEC,
  30         BPF_PROG_TYPE_SOCKET_FILTER,
  31         BPF_PROG_TYPE_KPROBE,
  32         BPF_PROG_TYPE_SCHED_CLS,
  33         BPF_PROG_TYPE_SCHED_ACT,
  34 };
  35
  36 /* BPF commands types */
  37 enum bpf_cmd {
  38         BPF_MAP_CREATE,
  39         BPF_MAP_LOOKUP_ELEM,
  40         BPF_MAP_UPDATE_ELEM,
  41         BPF_MAP_DELETE_ELEM,
  42         BPF_MAP_GET_NEXT_KEY,
  43         BPF_PROG_LOAD,
  44 };
  45
  46 /* BPF maps types */
  47 enum bpf_map_type {
  48         BPF_MAP_TYPE_UNSPEC,
  49         BPF_MAP_TYPE_HASH,
  50 };
  51
  52 /* union of anonymous structs used with TAP BPF commands */
  53 union bpf_attr {
  54         /* BPF_MAP_CREATE command */
  55         struct {
  56                 __u32   map_type;
  57                 __u32   key_size;
  58                 __u32   value_size;
  59                 __u32   max_entries;
  60                 __u32   map_flags;
  61                 __u32   inner_map_fd;
  62         };
  63
  64         /* BPF_MAP_UPDATE_ELEM, BPF_MAP_DELETE_ELEM commands */
  65         struct {
  66                 __u32           map_fd;
  67                 __aligned_u64   key;
  68                 union {
  69                         __aligned_u64 value;
  70                         __aligned_u64 next_key;
  71                 };
  72                 __u64           flags;
  73         };
  74
  75         /* BPF_PROG_LOAD command */
  76         struct {
  77                 __u32           prog_type;
  78                 __u32           insn_cnt;
  79                 __aligned_u64   insns;
  80                 __aligned_u64   license;
  81                 __u32           log_level;
  82                 __u32           log_size;
  83                 __aligned_u64   log_buf;
  84                 __u32           kern_version;
  85                 __u32           prog_flags;
  86         };
  87 } __attribute__((aligned(8)));
  88
  89 #ifndef __NR_bpf
  90 # if defined(__i386__)
  91 #  define __NR_bpf 357
  92 # elif defined(__x86_64__)
  93 #  define __NR_bpf 321
  94 # elif defined(__arm__)
  95 #  define __NR_bpf 386
  96 # elif defined(__aarch64__)
  97 #  define __NR_bpf 280
  98 # elif defined(__sparc__)
  99 #  define __NR_bpf 349
 100 # elif defined(__s390__)
 101 #  define __NR_bpf 351
 102 # elif defined(__powerpc__)
 103 #  define __NR_bpf 361
 104 # else
 105 #  error __NR_bpf not defined
 106 # endif
 107 #endif
 108
 109 enum {
 110         BPF_MAP_ID_KEY,
 111         BPF_MAP_ID_SIMPLE,
 112 };
 113
 114 static int bpf_load(enum bpf_prog_type type, const struct bpf_insn *insns,
 115                 size_t insns_cnt, const char *license);
 116
 117 #endif /* __TAP_BPF_H__ */