linux/samples/bpf/bpf_helpers.h

54 lines
1.9 KiB
C

#ifndef __BPF_HELPERS_H
#define __BPF_HELPERS_H
/* helper macro to place programs, maps, license in
* different sections in elf_bpf file. Section names
* are interpreted by elf_bpf loader
*/
#define SEC(NAME) __attribute__((section(NAME), used))
/* helper functions called from eBPF programs written in C */
static void *(*bpf_map_lookup_elem)(void *map, void *key) =
(void *) BPF_FUNC_map_lookup_elem;
static int (*bpf_map_update_elem)(void *map, void *key, void *value,
unsigned long long flags) =
(void *) BPF_FUNC_map_update_elem;
static int (*bpf_map_delete_elem)(void *map, void *key) =
(void *) BPF_FUNC_map_delete_elem;
static int (*bpf_probe_read)(void *dst, int size, void *unsafe_ptr) =
(void *) BPF_FUNC_probe_read;
static unsigned long long (*bpf_ktime_get_ns)(void) =
(void *) BPF_FUNC_ktime_get_ns;
static int (*bpf_trace_printk)(const char *fmt, int fmt_size, ...) =
(void *) BPF_FUNC_trace_printk;
/* llvm builtin functions that eBPF C program may use to
* emit BPF_LD_ABS and BPF_LD_IND instructions
*/
struct sk_buff;
unsigned long long load_byte(void *skb,
unsigned long long off) asm("llvm.bpf.load.byte");
unsigned long long load_half(void *skb,
unsigned long long off) asm("llvm.bpf.load.half");
unsigned long long load_word(void *skb,
unsigned long long off) asm("llvm.bpf.load.word");
/* a helper structure used by eBPF C program
* to describe map attributes to elf_bpf loader
*/
struct bpf_map_def {
unsigned int type;
unsigned int key_size;
unsigned int value_size;
unsigned int max_entries;
};
static int (*bpf_skb_store_bytes)(void *ctx, int off, void *from, int len, int flags) =
(void *) BPF_FUNC_skb_store_bytes;
static int (*bpf_l3_csum_replace)(void *ctx, int off, int from, int to, int flags) =
(void *) BPF_FUNC_l3_csum_replace;
static int (*bpf_l4_csum_replace)(void *ctx, int off, int from, int to, int flags) =
(void *) BPF_FUNC_l4_csum_replace;
#endif