Commit 68b18191 authored by Xu Kuohai's avatar Xu Kuohai Committed by Daniel Borkmann
Browse files

bpf, arm64: Support signed div/mod instructions 



Add JIT for signed div/mod instructions.

Signed-off-by: default avatarXu Kuohai <xukuohai@huawei.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Tested-by: default avatarFlorent Revest <revest@chromium.org>
Acked-by: default avatarFlorent Revest <revest@chromium.org>
Link: https://lore.kernel.org/bpf/20230815154158.717901-7-xukuohai@huaweicloud.com
parent c32b6ee5

arch/arm64/net/bpf_jit.h

+1 −0
Original line number Diff line number Diff line
@@ -234,6 +234,7 @@ 
#define A64_DATA2(sf, Rd, Rn, Rm, type) aarch64_insn_gen_data2(Rd, Rn, Rm, \

	A64_VARIANT(sf), AARCH64_INSN_DATA2_##type)

#define A64_UDIV(sf, Rd, Rn, Rm) A64_DATA2(sf, Rd, Rn, Rm, UDIV)

#define A64_SDIV(sf, Rd, Rn, Rm) A64_DATA2(sf, Rd, Rn, Rm, SDIV)

#define A64_LSLV(sf, Rd, Rn, Rm) A64_DATA2(sf, Rd, Rn, Rm, LSLV)

#define A64_LSRV(sf, Rd, Rn, Rm) A64_DATA2(sf, Rd, Rn, Rm, LSRV)

#define A64_ASRV(sf, Rd, Rn, Rm) A64_DATA2(sf, Rd, Rn, Rm, ASRV)

arch/arm64/net/bpf_jit_comp.c

+16 −4
Original line number Diff line number Diff line
@@ -828,11 +828,17 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, 
		break;

	case BPF_ALU | BPF_DIV | BPF_X:

	case BPF_ALU64 | BPF_DIV | BPF_X:

		if (!off)

			emit(A64_UDIV(is64, dst, dst, src), ctx);

		else

			emit(A64_SDIV(is64, dst, dst, src), ctx);

		break;

	case BPF_ALU | BPF_MOD | BPF_X:

	case BPF_ALU64 | BPF_MOD | BPF_X:

		if (!off)

			emit(A64_UDIV(is64, tmp, dst, src), ctx);

		else

			emit(A64_SDIV(is64, tmp, dst, src), ctx);

		emit(A64_MSUB(is64, dst, dst, tmp, src), ctx);

		break;

	case BPF_ALU | BPF_LSH | BPF_X:
@@ -959,12 +965,18 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, 
	case BPF_ALU | BPF_DIV | BPF_K:

	case BPF_ALU64 | BPF_DIV | BPF_K:

		emit_a64_mov_i(is64, tmp, imm, ctx);

		if (!off)

			emit(A64_UDIV(is64, dst, dst, tmp), ctx);

		else

			emit(A64_SDIV(is64, dst, dst, tmp), ctx);

		break;

	case BPF_ALU | BPF_MOD | BPF_K:

	case BPF_ALU64 | BPF_MOD | BPF_K:

		emit_a64_mov_i(is64, tmp2, imm, ctx);

		if (!off)

			emit(A64_UDIV(is64, tmp, dst, tmp2), ctx);

		else

			emit(A64_SDIV(is64, tmp, dst, tmp2), ctx);

		emit(A64_MSUB(is64, dst, dst, tmp, tmp2), ctx);

		break;

	case BPF_ALU | BPF_LSH | BPF_K: