From: Hengqi Chen <hengqi.chen@gmail.com>
Date: Wed, 8 Nov 2023 06:12:21 +0000 (+0800)
Subject: LoongArch: BPF: Support signed mod instructions
X-Git-Tag: v6.7-rc1~3^2~1
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=7b6b13d32965ad7f1eb889d1a7058868a88eb29f;p=users%2Fdwmw2%2Flinux.git

LoongArch: BPF: Support signed mod instructions

Add support for signed mod instructions.

Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
---

diff --git a/arch/loongarch/net/bpf_jit.c b/arch/loongarch/net/bpf_jit.c
index 7c0d129b82a4a..169ff8b3915e6 100644
--- a/arch/loongarch/net/bpf_jit.c
+++ b/arch/loongarch/net/bpf_jit.c
@@ -588,20 +588,36 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext
 	/* dst = dst % src */
 	case BPF_ALU | BPF_MOD | BPF_X:
 	case BPF_ALU64 | BPF_MOD | BPF_X:
-		emit_zext_32(ctx, dst, is32);
-		move_reg(ctx, t1, src);
-		emit_zext_32(ctx, t1, is32);
-		emit_insn(ctx, moddu, dst, dst, t1);
-		emit_zext_32(ctx, dst, is32);
+		if (!off) {
+			emit_zext_32(ctx, dst, is32);
+			move_reg(ctx, t1, src);
+			emit_zext_32(ctx, t1, is32);
+			emit_insn(ctx, moddu, dst, dst, t1);
+			emit_zext_32(ctx, dst, is32);
+		} else {
+			emit_sext_32(ctx, dst, is32);
+			move_reg(ctx, t1, src);
+			emit_sext_32(ctx, t1, is32);
+			emit_insn(ctx, modd, dst, dst, t1);
+			emit_sext_32(ctx, dst, is32);
+		}
 		break;
 
 	/* dst = dst % imm */
 	case BPF_ALU | BPF_MOD | BPF_K:
 	case BPF_ALU64 | BPF_MOD | BPF_K:
-		move_imm(ctx, t1, imm, is32);
-		emit_zext_32(ctx, dst, is32);
-		emit_insn(ctx, moddu, dst, dst, t1);
-		emit_zext_32(ctx, dst, is32);
+		if (!off) {
+			move_imm(ctx, t1, imm, is32);
+			emit_zext_32(ctx, dst, is32);
+			emit_insn(ctx, moddu, dst, dst, t1);
+			emit_zext_32(ctx, dst, is32);
+		} else {
+			move_imm(ctx, t1, imm, false);
+			emit_sext_32(ctx, t1, is32);
+			emit_sext_32(ctx, dst, is32);
+			emit_insn(ctx, modd, dst, dst, t1);
+			emit_sext_32(ctx, dst, is32);
+		}
 		break;
 
 	/* dst = -dst */