Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit a67b375f authored by David Daney's avatar David Daney Committed by David S. Miller
Browse files

MIPS, bpf: Implement JLT, JLE, JSLT and JSLE ops in the eBPF JIT. 



Signed-off-by: default avatarDavid Daney <david.daney@cavium.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 8d8d18c3

arch/mips/net/ebpf_jit.c

+72 −29
Original line number Diff line number Diff line
@@ -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;

				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;

			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 @@ static int build_one_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, 
		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 @@ static int build_one_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, 
				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;