From a67b375fdc5b21ae3a15761f9c5ef7bd352b5f7d Mon Sep 17 00:00:00 2001 From: David Daney Date: Fri, 18 Aug 2017 16:40:32 -0700 Subject: [PATCH] MIPS, bpf: Implement JLT, JLE, JSLT and JSLE ops in the eBPF JIT. Signed-off-by: David Daney Signed-off-by: David S. Miller --- arch/mips/net/ebpf_jit.c | 101 ++++++++++++++++++++++++++++----------- 1 file changed, 72 insertions(+), 29 deletions(-) diff --git a/arch/mips/net/ebpf_jit.c b/arch/mips/net/ebpf_jit.c index 721216b0f8e4..c1e21cbdd336 100644 --- a/arch/mips/net/ebpf_jit.c +++ b/arch/mips/net/ebpf_jit.c @@ -990,8 +990,12 @@ static int build_one_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, goto jeq_common; case BPF_JMP | BPF_JEQ | BPF_X: /* JMP_REG */ case BPF_JMP | BPF_JNE | BPF_X: + case BPF_JMP | BPF_JSLT | BPF_X: + case BPF_JMP | BPF_JSLE | BPF_X: case BPF_JMP | BPF_JSGT | BPF_X: case BPF_JMP | BPF_JSGE | BPF_X: + case BPF_JMP | BPF_JLT | BPF_X: + case BPF_JMP | BPF_JLE | BPF_X: case BPF_JMP | BPF_JGT | BPF_X: case BPF_JMP | BPF_JGE | BPF_X: case BPF_JMP | BPF_JSET | BPF_X: @@ -1013,28 +1017,34 @@ static int build_one_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, cmp_eq = false; dst = MIPS_R_AT; src = MIPS_R_ZERO; - } else if (BPF_OP(insn->code) == BPF_JSGT) { + } else if (BPF_OP(insn->code) == BPF_JSGT || BPF_OP(insn->code) == BPF_JSLE) { emit_instr(ctx, dsubu, MIPS_R_AT, dst, src); if ((insn + 1)->code == (BPF_JMP | BPF_EXIT) && insn->off == 1) { b_off = b_imm(exit_idx, ctx); if (is_bad_offset(b_off)) return -E2BIG; - emit_instr(ctx, blez, MIPS_R_AT, b_off); + if (BPF_OP(insn->code) == BPF_JSGT) + emit_instr(ctx, blez, MIPS_R_AT, b_off); + else + emit_instr(ctx, bgtz, MIPS_R_AT, b_off); emit_instr(ctx, nop); return 2; /* We consumed the exit. */ } b_off = b_imm(this_idx + insn->off + 1, ctx); if (is_bad_offset(b_off)) return -E2BIG; - emit_instr(ctx, bgtz, MIPS_R_AT, b_off); + if (BPF_OP(insn->code) == BPF_JSGT) + emit_instr(ctx, bgtz, MIPS_R_AT, b_off); + else + emit_instr(ctx, blez, MIPS_R_AT, b_off); emit_instr(ctx, nop); break; - } else if (BPF_OP(insn->code) == BPF_JSGE) { + } else if (BPF_OP(insn->code) == BPF_JSGE || BPF_OP(insn->code) == BPF_JSLT) { emit_instr(ctx, slt, MIPS_R_AT, dst, src); - cmp_eq = true; + cmp_eq = BPF_OP(insn->code) == BPF_JSGE; dst = MIPS_R_AT; src = MIPS_R_ZERO; - } else if (BPF_OP(insn->code) == BPF_JGT) { + } else if (BPF_OP(insn->code) == BPF_JGT || BPF_OP(insn->code) == BPF_JLE) { /* dst or src could be AT */ emit_instr(ctx, dsubu, MIPS_R_T8, dst, src); emit_instr(ctx, sltu, MIPS_R_AT, dst, src); @@ -1042,12 +1052,12 @@ static int build_one_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, emit_instr(ctx, movz, MIPS_R_T9, MIPS_R_SP, MIPS_R_T8); emit_instr(ctx, movn, MIPS_R_T9, MIPS_R_ZERO, MIPS_R_T8); emit_instr(ctx, or, MIPS_R_AT, MIPS_R_T9, MIPS_R_AT); - cmp_eq = true; + cmp_eq = BPF_OP(insn->code) == BPF_JGT; dst = MIPS_R_AT; src = MIPS_R_ZERO; - } else if (BPF_OP(insn->code) == BPF_JGE) { + } else if (BPF_OP(insn->code) == BPF_JGE || BPF_OP(insn->code) == BPF_JLT) { emit_instr(ctx, sltu, MIPS_R_AT, dst, src); - cmp_eq = true; + cmp_eq = BPF_OP(insn->code) == BPF_JGE; dst = MIPS_R_AT; src = MIPS_R_ZERO; } else { /* JNE/JEQ case */ @@ -1110,6 +1120,8 @@ jeq_common: break; case BPF_JMP | BPF_JSGT | BPF_K: /* JMP_IMM */ case BPF_JMP | BPF_JSGE | BPF_K: /* JMP_IMM */ + case BPF_JMP | BPF_JSLT | BPF_K: /* JMP_IMM */ + case BPF_JMP | BPF_JSLE | BPF_K: /* JMP_IMM */ cmp_eq = (BPF_OP(insn->code) == BPF_JSGE); dst = ebpf_to_mips_reg(ctx, insn, dst_reg_fp_ok); if (dst < 0) @@ -1120,65 +1132,92 @@ jeq_common: b_off = b_imm(exit_idx, ctx); if (is_bad_offset(b_off)) return -E2BIG; - if (cmp_eq) - emit_instr(ctx, bltz, dst, b_off); - else + switch (BPF_OP(insn->code)) { + case BPF_JSGT: emit_instr(ctx, blez, dst, b_off); + break; + case BPF_JSGE: + emit_instr(ctx, bltz, dst, b_off); + break; + case BPF_JSLT: + emit_instr(ctx, bgez, dst, b_off); + break; + case BPF_JSLE: + emit_instr(ctx, bgtz, dst, b_off); + break; + } emit_instr(ctx, nop); return 2; /* We consumed the exit. */ } b_off = b_imm(this_idx + insn->off + 1, ctx); if (is_bad_offset(b_off)) return -E2BIG; - if (cmp_eq) - emit_instr(ctx, bgez, dst, b_off); - else + switch (BPF_OP(insn->code)) { + case BPF_JSGT: emit_instr(ctx, bgtz, dst, b_off); + break; + case BPF_JSGE: + emit_instr(ctx, bgez, dst, b_off); + break; + case BPF_JSLT: + emit_instr(ctx, bltz, dst, b_off); + break; + case BPF_JSLE: + emit_instr(ctx, blez, dst, b_off); + break; + } emit_instr(ctx, nop); break; } /* * only "LT" compare available, so we must use imm + 1 - * to generate "GT" + * to generate "GT" and imm -1 to generate LE */ - t64s = insn->imm + (cmp_eq ? 0 : 1); + if (BPF_OP(insn->code) == BPF_JSGT) + t64s = insn->imm + 1; + else if (BPF_OP(insn->code) == BPF_JSLE) + t64s = insn->imm + 1; + else + t64s = insn->imm; + + cmp_eq = BPF_OP(insn->code) == BPF_JSGT || BPF_OP(insn->code) == BPF_JSGE; if (t64s >= S16_MIN && t64s <= S16_MAX) { emit_instr(ctx, slti, MIPS_R_AT, dst, (int)t64s); src = MIPS_R_AT; dst = MIPS_R_ZERO; - cmp_eq = true; goto jeq_common; } emit_const_to_reg(ctx, MIPS_R_AT, (u64)t64s); emit_instr(ctx, slt, MIPS_R_AT, dst, MIPS_R_AT); src = MIPS_R_AT; dst = MIPS_R_ZERO; - cmp_eq = true; goto jeq_common; case BPF_JMP | BPF_JGT | BPF_K: case BPF_JMP | BPF_JGE | BPF_K: + case BPF_JMP | BPF_JLT | BPF_K: + case BPF_JMP | BPF_JLE | BPF_K: cmp_eq = (BPF_OP(insn->code) == BPF_JGE); dst = ebpf_to_mips_reg(ctx, insn, dst_reg_fp_ok); if (dst < 0) return dst; /* * only "LT" compare available, so we must use imm + 1 - * to generate "GT" + * to generate "GT" and imm -1 to generate LE */ - t64s = (u64)(u32)(insn->imm) + (cmp_eq ? 0 : 1); - if (t64s >= 0 && t64s <= S16_MAX) { - emit_instr(ctx, sltiu, MIPS_R_AT, dst, (int)t64s); - src = MIPS_R_AT; - dst = MIPS_R_ZERO; - cmp_eq = true; - goto jeq_common; - } + if (BPF_OP(insn->code) == BPF_JGT) + t64s = (u64)(u32)(insn->imm) + 1; + else if (BPF_OP(insn->code) == BPF_JLE) + t64s = (u64)(u32)(insn->imm) + 1; + else + t64s = (u64)(u32)(insn->imm); + + cmp_eq = BPF_OP(insn->code) == BPF_JGT || BPF_OP(insn->code) == BPF_JGE; + emit_const_to_reg(ctx, MIPS_R_AT, (u64)t64s); emit_instr(ctx, sltu, MIPS_R_AT, dst, MIPS_R_AT); src = MIPS_R_AT; dst = MIPS_R_ZERO; - cmp_eq = true; goto jeq_common; case BPF_JMP | BPF_JSET | BPF_K: /* JMP_IMM */ @@ -1712,10 +1751,14 @@ static int reg_val_propagate_range(struct jit_ctx *ctx, u64 initial_rvt, case BPF_JEQ: case BPF_JGT: case BPF_JGE: + case BPF_JLT: + case BPF_JLE: case BPF_JSET: case BPF_JNE: case BPF_JSGT: case BPF_JSGE: + case BPF_JSLT: + case BPF_JSLE: if (follow_taken) { rvt[idx] |= RVT_BRANCH_TAKEN; idx += insn->off;