diff options
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/lib/bpf/xsk.c | 42 |
1 files changed, 32 insertions, 10 deletions
diff --git a/tools/lib/bpf/xsk.c b/tools/lib/bpf/xsk.c index 78665005b6f7..9a2af445ef23 100644 --- a/tools/lib/bpf/xsk.c +++ b/tools/lib/bpf/xsk.c @@ -274,33 +274,55 @@ static int xsk_load_xdp_prog(struct xsk_socket *xsk) /* This is the C-program: * SEC("xdp_sock") int xdp_sock_prog(struct xdp_md *ctx) * { - * int index = ctx->rx_queue_index; + * int ret, index = ctx->rx_queue_index; * * // A set entry here means that the correspnding queue_id * // has an active AF_XDP socket bound to it. + * ret = bpf_redirect_map(&xsks_map, index, XDP_PASS); + * if (ret > 0) + * return ret; + * + * // Fallback for pre-5.3 kernels, not supporting default + * // action in the flags parameter. * if (bpf_map_lookup_elem(&xsks_map, &index)) * return bpf_redirect_map(&xsks_map, index, 0); - * * return XDP_PASS; * } */ struct bpf_insn prog[] = { - /* r1 = *(u32 *)(r1 + 16) */ - BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_1, 16), - /* *(u32 *)(r10 - 4) = r1 */ - BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_1, -4), + /* r2 = *(u32 *)(r1 + 16) */ + BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, 16), + /* *(u32 *)(r10 - 4) = r2 */ + BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_2, -4), + /* r1 = xskmap[] */ + BPF_LD_MAP_FD(BPF_REG_1, xsk->xsks_map_fd), + /* r3 = XDP_PASS */ + BPF_MOV64_IMM(BPF_REG_3, 2), + /* call bpf_redirect_map */ + BPF_EMIT_CALL(BPF_FUNC_redirect_map), + /* if w0 != 0 goto pc+13 */ + BPF_JMP32_IMM(BPF_JSGT, BPF_REG_0, 0, 13), + /* r2 = r10 */ BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), + /* r2 += -4 */ BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4), + /* r1 = xskmap[] */ BPF_LD_MAP_FD(BPF_REG_1, xsk->xsks_map_fd), + /* call bpf_map_lookup_elem */ BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem), + /* r1 = r0 */ BPF_MOV64_REG(BPF_REG_1, BPF_REG_0), - BPF_MOV32_IMM(BPF_REG_0, 2), - /* if r1 == 0 goto +5 */ + /* r0 = XDP_PASS */ + BPF_MOV64_IMM(BPF_REG_0, 2), + /* if r1 == 0 goto pc+5 */ BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 5), /* r2 = *(u32 *)(r10 - 4) */ - BPF_LD_MAP_FD(BPF_REG_1, xsk->xsks_map_fd), BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_10, -4), - BPF_MOV32_IMM(BPF_REG_3, 0), + /* r1 = xskmap[] */ + BPF_LD_MAP_FD(BPF_REG_1, xsk->xsks_map_fd), + /* r3 = 0 */ + BPF_MOV64_IMM(BPF_REG_3, 0), + /* call bpf_redirect_map */ BPF_EMIT_CALL(BPF_FUNC_redirect_map), /* The jumps are to this instruction */ BPF_EXIT_INSN(), |