From 249b812d8005ec38e351ee763ceb85d56b155064 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Mon, 1 Dec 2014 15:06:37 -0800 Subject: samples: bpf: elf_bpf file loader simple .o parser and loader using BPF syscall. .o is a standard ELF generated by LLVM backend It parses elf file compiled by llvm .c->.o - parses 'maps' section and creates maps via BPF syscall - parses 'license' section and passes it to syscall - parses elf relocations for BPF maps and adjusts BPF_LD_IMM64 insns by storing map_fd into insn->imm and marking such insns as BPF_PSEUDO_MAP_FD - loads eBPF programs via BPF syscall One ELF file can contain multiple BPF programs. int load_bpf_file(char *path); populates prog_fd[] and map_fd[] with FDs received from bpf syscall bpf_helpers.h - helper functions available to eBPF programs written in C Signed-off-by: Alexei Starovoitov Signed-off-by: David S. Miller --- samples/bpf/bpf_load.h | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) create mode 100644 samples/bpf/bpf_load.h (limited to 'samples/bpf/bpf_load.h') diff --git a/samples/bpf/bpf_load.h b/samples/bpf/bpf_load.h new file mode 100644 index 000000000000..27789a34f5e6 --- /dev/null +++ b/samples/bpf/bpf_load.h @@ -0,0 +1,24 @@ +#ifndef __BPF_LOAD_H +#define __BPF_LOAD_H + +#define MAX_MAPS 32 +#define MAX_PROGS 32 + +extern int map_fd[MAX_MAPS]; +extern int prog_fd[MAX_PROGS]; + +/* parses elf file compiled by llvm .c->.o + * . parses 'maps' section and creates maps via BPF syscall + * . parses 'license' section and passes it to syscall + * . parses elf relocations for BPF maps and adjusts BPF_LD_IMM64 insns by + * storing map_fd into insn->imm and marking such insns as BPF_PSEUDO_MAP_FD + * . loads eBPF programs via BPF syscall + * + * One ELF file can contain multiple BPF programs which will be loaded + * and their FDs stored stored in prog_fd array + * + * returns zero on success + */ +int load_bpf_file(char *path); + +#endif -- cgit