Re: [PATCH bpf-next v1 3/4] LoongArch: Add BPF JIT support

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On 08/22/2022 09:58 AM, Youling Tang wrote:
On 08/20/2022 07:50 PM, Tiezhu Yang wrote:
BPF programs are normally handled by a BPF interpreter, add BPF JIT
support for LoongArch to allow the kernel to generate native code
when a program is loaded into the kernel, this will significantly
speed-up processing of BPF programs.

Co-developed-by: Youling Tang <tangyouling@xxxxxxxxxxx>
Signed-off-by: Youling Tang <tangyouling@xxxxxxxxxxx>
Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
---
 arch/loongarch/Kbuild             |    1 +
 arch/loongarch/Kconfig            |    1 +
 arch/loongarch/include/asm/inst.h |  185 ++++++
 arch/loongarch/net/Makefile       |    7 +
 arch/loongarch/net/bpf_jit.c      | 1113
+++++++++++++++++++++++++++++++++++++
 arch/loongarch/net/bpf_jit.h      |  308 ++++++++++
 6 files changed, 1615 insertions(+)
 create mode 100644 arch/loongarch/net/Makefile
 create mode 100644 arch/loongarch/net/bpf_jit.c
 create mode 100644 arch/loongarch/net/bpf_jit.h

diff --git a/arch/loongarch/Kbuild b/arch/loongarch/Kbuild
index ab5373d..b01f5cd 100644
--- a/arch/loongarch/Kbuild
+++ b/arch/loongarch/Kbuild
@@ -1,5 +1,6 @@
 obj-y += kernel/
 obj-y += mm/
+obj-y += net/
 obj-y += vdso/

 # for cleaning
diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
index 4abc9a2..6d9d846 100644
--- a/arch/loongarch/Kconfig
+++ b/arch/loongarch/Kconfig
@@ -82,6 +82,7 @@ config LOONGARCH
     select HAVE_CONTEXT_TRACKING_USER
     select HAVE_DEBUG_STACKOVERFLOW
     select HAVE_DMA_CONTIGUOUS
+    select HAVE_EBPF_JIT if 64BIT
     select HAVE_EXIT_THREAD
     select HAVE_FAST_GUP
     select HAVE_GENERIC_VDSO
diff --git a/arch/loongarch/include/asm/inst.h
b/arch/loongarch/include/asm/inst.h
index de19a96..ac06f2e 100644
--- a/arch/loongarch/include/asm/inst.h
+++ b/arch/loongarch/include/asm/inst.h
@@ -288,4 +288,189 @@ static inline bool unsigned_imm_check(unsigned
long val, unsigned int bit)
     return val < (1UL << bit);
 }

+#define DEF_EMIT_REG0I26_FORMAT(NAME, OP)                \
+static inline void emit_##NAME(union loongarch_instruction *insn,    \
+                   int offset)                \
+{                                    \
+    unsigned int immediate_l, immediate_h;                \
+                                    \
+    immediate_l = offset & 0xffff;                    \
+    offset >>= 16;                            \
+    immediate_h = offset & 0x3ff;                    \
+                                    \
+    insn->reg0i26_format.opcode = OP;                \
+    insn->reg0i26_format.immediate_l = immediate_l;            \
+    insn->reg0i26_format.immediate_h = immediate_h;            \
+}
+
+DEF_EMIT_REG0I26_FORMAT(b, b_op)
+
+#define DEF_EMIT_REG1I20_FORMAT(NAME, OP)                \
+static inline void emit_##NAME(union loongarch_instruction *insn,    \
+                   enum loongarch_gpr rd, int imm)        \
+{                                    \
+    insn->reg1i20_format.opcode = OP;                \
+    insn->reg1i20_format.immediate = imm;                \
+    insn->reg1i20_format.rd = rd;                    \
+}
+
+DEF_EMIT_REG1I20_FORMAT(lu12iw, lu12iw_op)
+DEF_EMIT_REG1I20_FORMAT(lu32id, lu32id_op)

We can delete the larch_insn_gen_{lu32id, lu52id, jirl} functions in
inst.c and use emit_xxx.

The implementation of emit_plt_entry() is similarly modified as follows:
struct plt_entry {
        union loongarch_instruction lu12iw;
        union loongarch_instruction lu32id;
        union loongarch_instruction lu52id;
        union loongarch_instruction jirl;
};

static inline struct plt_entry emit_plt_entry(unsigned long val)
{
        union loongarch_instruction *lu12iw, *lu32id, *lu52id, *jirl;

        emit_lu32id(lu12iw, LOONGARCH_GPR_T1, ADDR_IMM(val, LU12IW));

Sorry, this is emit_lu12iw.

        emit_lu32id(lu32id, LOONGARCH_GPR_T1, ADDR_IMM(val, LU32ID));
        emit_lu52id(lu52id, LOONGARCH_GPR_T1, LOONGARCH_GPR_T1,
ADDR_IMM(val, LU52ID));
        emit_jirl(jirl, LOONGARCH_GPR_T1, 0, (val & 0xfff) >> 2);

        return (struct plt_entry) { *lu12iw, *lu32id, *lu52id, *jirl };
}

Thanks,
Youling

+DEF_EMIT_REG1I20_FORMAT(pcaddu18i, pcaddu18i_op)
+
+#define DEF_EMIT_REG2_FORMAT(NAME, OP)                    \
+static inline void emit_##NAME(union loongarch_instruction *insn,    \
+                   enum loongarch_gpr rd,            \
+                   enum loongarch_gpr rj)            \
+{                                    \
+    insn->reg2_format.opcode = OP;                    \
+    insn->reg2_format.rd = rd;                    \
+    insn->reg2_format.rj = rj;                    \
+}
+
+DEF_EMIT_REG2_FORMAT(revb2h, revb2h_op)
+DEF_EMIT_REG2_FORMAT(revb2w, revb2w_op)
+DEF_EMIT_REG2_FORMAT(revbd, revbd_op)
+
+#define DEF_EMIT_REG2I5_FORMAT(NAME, OP)                \
+static inline void emit_##NAME(union loongarch_instruction *insn,    \
+                   enum loongarch_gpr rd,            \
+                   enum loongarch_gpr rj,            \
+                   int imm)                    \
+{                                    \
+    insn->reg2i5_format.opcode = OP;                \
+    insn->reg2i5_format.immediate = imm;                \
+    insn->reg2i5_format.rd = rd;                    \
+    insn->reg2i5_format.rj = rj;                    \
+}
+
+DEF_EMIT_REG2I5_FORMAT(slliw, slliw_op)
+DEF_EMIT_REG2I5_FORMAT(srliw, srliw_op)
+DEF_EMIT_REG2I5_FORMAT(sraiw, sraiw_op)
+
+#define DEF_EMIT_REG2I6_FORMAT(NAME, OP)                \
+static inline void emit_##NAME(union loongarch_instruction *insn,    \
+                   enum loongarch_gpr rd,            \
+                   enum loongarch_gpr rj,            \
+                   int imm)                    \
+{                                    \
+    insn->reg2i6_format.opcode = OP;                \
+    insn->reg2i6_format.immediate = imm;                \
+    insn->reg2i6_format.rd = rd;                    \
+    insn->reg2i6_format.rj = rj;                    \
+}
+
+DEF_EMIT_REG2I6_FORMAT(sllid, sllid_op)
+DEF_EMIT_REG2I6_FORMAT(srlid, srlid_op)
+DEF_EMIT_REG2I6_FORMAT(sraid, sraid_op)
+
+#define DEF_EMIT_REG2I12_FORMAT(NAME, OP)                \
+static inline void emit_##NAME(union loongarch_instruction *insn,    \
+                   enum loongarch_gpr rd,            \
+                   enum loongarch_gpr rj,            \
+                   int imm)                    \
+{                                    \
+    insn->reg2i12_format.opcode = OP;                \
+    insn->reg2i12_format.immediate = imm;                \
+    insn->reg2i12_format.rd = rd;                    \
+    insn->reg2i12_format.rj = rj;                    \
+}
+
+DEF_EMIT_REG2I12_FORMAT(addiw, addiw_op)
+DEF_EMIT_REG2I12_FORMAT(addid, addid_op)
+DEF_EMIT_REG2I12_FORMAT(lu52id, lu52id_op)
+DEF_EMIT_REG2I12_FORMAT(andi, andi_op)
+DEF_EMIT_REG2I12_FORMAT(ori, ori_op)
+DEF_EMIT_REG2I12_FORMAT(xori, xori_op)
+DEF_EMIT_REG2I12_FORMAT(ldbu, ldbu_op)
+DEF_EMIT_REG2I12_FORMAT(ldhu, ldhu_op)
+DEF_EMIT_REG2I12_FORMAT(ldwu, ldwu_op)
+DEF_EMIT_REG2I12_FORMAT(ldd, ldd_op)
+DEF_EMIT_REG2I12_FORMAT(stb, stb_op)
+DEF_EMIT_REG2I12_FORMAT(sth, sth_op)
+DEF_EMIT_REG2I12_FORMAT(stw, stw_op)
+DEF_EMIT_REG2I12_FORMAT(std, std_op)
+
+#define DEF_EMIT_REG2I14_FORMAT(NAME, OP)                \
+static inline void emit_##NAME(union loongarch_instruction *insn,    \
+                   enum loongarch_gpr rd,            \
+                   enum loongarch_gpr rj,            \
+                   int imm)                    \
+{                                    \
+    insn->reg2i14_format.opcode = OP;                \
+    insn->reg2i14_format.immediate = imm;                \
+    insn->reg2i14_format.rd = rd;                    \
+    insn->reg2i14_format.rj = rj;                    \
+}
+
+DEF_EMIT_REG2I14_FORMAT(llw, llw_op)
+DEF_EMIT_REG2I14_FORMAT(scw, scw_op)
+DEF_EMIT_REG2I14_FORMAT(lld, lld_op)
+DEF_EMIT_REG2I14_FORMAT(scd, scd_op)
+
+#define DEF_EMIT_REG2I16_FORMAT(NAME, OP)                \
+static inline void emit_##NAME(union loongarch_instruction *insn,    \
+                   enum loongarch_gpr rj,            \
+                   enum loongarch_gpr rd,            \
+                   int offset)                \
+{                                    \
+    insn->reg2i16_format.opcode = OP;                \
+    insn->reg2i16_format.immediate = offset;            \
+    insn->reg2i16_format.rj = rj;                    \
+    insn->reg2i16_format.rd = rd;                    \
+}
+
+DEF_EMIT_REG2I16_FORMAT(beq, beq_op)
+DEF_EMIT_REG2I16_FORMAT(bne, bne_op)
+DEF_EMIT_REG2I16_FORMAT(blt, blt_op)
+DEF_EMIT_REG2I16_FORMAT(bge, bge_op)
+DEF_EMIT_REG2I16_FORMAT(bltu, bltu_op)
+DEF_EMIT_REG2I16_FORMAT(bgeu, bgeu_op)
+DEF_EMIT_REG2I16_FORMAT(jirl, jirl_op)
+
+#define DEF_EMIT_REG3_FORMAT(NAME, OP)                    \
+static inline void emit_##NAME(union loongarch_instruction *insn,    \
+                   enum loongarch_gpr rd,            \
+                   enum loongarch_gpr rj,            \
+                   enum loongarch_gpr rk)            \
+{                                    \
+    insn->reg3_format.opcode = OP;                    \
+    insn->reg3_format.rd = rd;                    \
+    insn->reg3_format.rj = rj;                    \
+    insn->reg3_format.rk = rk;                    \
+}
+
+DEF_EMIT_REG3_FORMAT(addd, addd_op)
+DEF_EMIT_REG3_FORMAT(subd, subd_op)
+DEF_EMIT_REG3_FORMAT(muld, muld_op)
+DEF_EMIT_REG3_FORMAT(divdu, divdu_op)
+DEF_EMIT_REG3_FORMAT(moddu, moddu_op)
+DEF_EMIT_REG3_FORMAT(and, and_op)
+DEF_EMIT_REG3_FORMAT(or, or_op)
+DEF_EMIT_REG3_FORMAT(xor, xor_op)
+DEF_EMIT_REG3_FORMAT(sllw, sllw_op)
+DEF_EMIT_REG3_FORMAT(slld, slld_op)
+DEF_EMIT_REG3_FORMAT(srlw, srlw_op)
+DEF_EMIT_REG3_FORMAT(srld, srld_op)
+DEF_EMIT_REG3_FORMAT(sraw, sraw_op)
+DEF_EMIT_REG3_FORMAT(srad, srad_op)
+DEF_EMIT_REG3_FORMAT(ldxbu, ldxbu_op)
+DEF_EMIT_REG3_FORMAT(ldxhu, ldxhu_op)
+DEF_EMIT_REG3_FORMAT(ldxwu, ldxwu_op)
+DEF_EMIT_REG3_FORMAT(ldxd, ldxd_op)
+DEF_EMIT_REG3_FORMAT(stxb, stxb_op)
+DEF_EMIT_REG3_FORMAT(stxh, stxh_op)
+DEF_EMIT_REG3_FORMAT(stxw, stxw_op)
+DEF_EMIT_REG3_FORMAT(stxd, stxd_op)
+DEF_EMIT_REG3_FORMAT(amaddw, amaddw_op)
+DEF_EMIT_REG3_FORMAT(amaddd, amaddd_op)
+DEF_EMIT_REG3_FORMAT(amandw, amandw_op)
+DEF_EMIT_REG3_FORMAT(amandd, amandd_op)
+DEF_EMIT_REG3_FORMAT(amorw, amorw_op)
+DEF_EMIT_REG3_FORMAT(amord, amord_op)
+DEF_EMIT_REG3_FORMAT(amxorw, amxorw_op)
+DEF_EMIT_REG3_FORMAT(amxord, amxord_op)
+DEF_EMIT_REG3_FORMAT(amswapw, amswapw_op)
+DEF_EMIT_REG3_FORMAT(amswapd, amswapd_op)
+
 #endif /* _ASM_INST_H */
diff --git a/arch/loongarch/net/Makefile b/arch/loongarch/net/Makefile
new file mode 100644
index 0000000..1ec12a0
--- /dev/null
+++ b/arch/loongarch/net/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Makefile for arch/loongarch/net
+#
+# Copyright (C) 2022 Loongson Technology Corporation Limited
+#
+obj-$(CONFIG_BPF_JIT) += bpf_jit.o
diff --git a/arch/loongarch/net/bpf_jit.c b/arch/loongarch/net/bpf_jit.c
new file mode 100644
index 0000000..2f41b9b
--- /dev/null
+++ b/arch/loongarch/net/bpf_jit.c
@@ -0,0 +1,1113 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * BPF JIT compiler for LoongArch
+ *
+ * Copyright (C) 2022 Loongson Technology Corporation Limited
+ */
+#include "bpf_jit.h"
+
+#define REG_TCC        LOONGARCH_GPR_A6
+#define TCC_SAVED    LOONGARCH_GPR_S5
+
+#define SAVE_RA        BIT(0)
+#define SAVE_TCC    BIT(1)
+
+static const int regmap[] = {
+    /* return value from in-kernel function, and exit value for eBPF
program */
+    [BPF_REG_0] = LOONGARCH_GPR_A5,
+    /* arguments from eBPF program to in-kernel function */
+    [BPF_REG_1] = LOONGARCH_GPR_A0,
+    [BPF_REG_2] = LOONGARCH_GPR_A1,
+    [BPF_REG_3] = LOONGARCH_GPR_A2,
+    [BPF_REG_4] = LOONGARCH_GPR_A3,
+    [BPF_REG_5] = LOONGARCH_GPR_A4,
+    /* callee saved registers that in-kernel function will preserve */
+    [BPF_REG_6] = LOONGARCH_GPR_S0,
+    [BPF_REG_7] = LOONGARCH_GPR_S1,
+    [BPF_REG_8] = LOONGARCH_GPR_S2,
+    [BPF_REG_9] = LOONGARCH_GPR_S3,
+    /* read-only frame pointer to access stack */
+    [BPF_REG_FP] = LOONGARCH_GPR_S4,
+    /* temporary register for blinding constants */
+    [BPF_REG_AX] = LOONGARCH_GPR_T0,
+};
+
+static void mark_call(struct jit_ctx *ctx)
+{
+    ctx->flags |= SAVE_RA;
+}
+
+static void mark_tail_call(struct jit_ctx *ctx)
+{
+    ctx->flags |= SAVE_TCC;
+}
+
+static bool seen_call(struct jit_ctx *ctx)
+{
+    return (ctx->flags & SAVE_RA);
+}
+
+static bool seen_tail_call(struct jit_ctx *ctx)
+{
+    return (ctx->flags & SAVE_TCC);
+}
+
+static u8 tail_call_reg(struct jit_ctx *ctx)
+{
+    if (seen_call(ctx))
+        return TCC_SAVED;
+
+    return REG_TCC;
+}
+
+/*
+ * eBPF prog stack layout:
+ *
+ *                                        high
+ * original $sp ------------> +-------------------------+
<--LOONGARCH_GPR_FP
+ *                            |           $ra           |
+ *                            +-------------------------+
+ *                            |           $fp           |
+ *                            +-------------------------+
+ *                            |           $s0           |
+ *                            +-------------------------+
+ *                            |           $s1           |
+ *                            +-------------------------+
+ *                            |           $s2           |
+ *                            +-------------------------+
+ *                            |           $s3           |
+ *                            +-------------------------+
+ *                            |           $s4           |
+ *                            +-------------------------+
+ *                            |           $s5           |
+ *                            +-------------------------+ <--BPF_REG_FP
+ *                            |  prog->aux->stack_depth |
+ *                            |        (optional)       |
+ * current $sp -------------> +-------------------------+
+ *                                        low
+ */
+static void build_prologue(struct jit_ctx *ctx)
+{
+    int stack_adjust = 0, store_offset, bpf_stack_adjust;
+
+    bpf_stack_adjust = round_up(ctx->prog->aux->stack_depth, 16);
+
+    /* To store ra, fp, s0, s1, s2, s3, s4 and s5. */
+    stack_adjust += sizeof(long) * 8;
+
+    stack_adjust = round_up(stack_adjust, 16);
+    stack_adjust += bpf_stack_adjust;
+
+    /*
+     * First instruction initializes the tail call count (TCC).
+     * On tail call we skip this instruction, and the TCC is
+     * passed in REG_TCC from the caller.
+     */
+    emit_insn(ctx, addid, REG_TCC, LOONGARCH_GPR_ZERO,
MAX_TAIL_CALL_CNT);
+
+    emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP,
-stack_adjust);
+
+    store_offset = stack_adjust - sizeof(long);
+    emit_insn(ctx, std, LOONGARCH_GPR_RA, LOONGARCH_GPR_SP,
store_offset);
+
+    store_offset -= sizeof(long);
+    emit_insn(ctx, std, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP,
store_offset);
+
+    store_offset -= sizeof(long);
+    emit_insn(ctx, std, LOONGARCH_GPR_S0, LOONGARCH_GPR_SP,
store_offset);
+
+    store_offset -= sizeof(long);
+    emit_insn(ctx, std, LOONGARCH_GPR_S1, LOONGARCH_GPR_SP,
store_offset);
+
+    store_offset -= sizeof(long);
+    emit_insn(ctx, std, LOONGARCH_GPR_S2, LOONGARCH_GPR_SP,
store_offset);
+
+    store_offset -= sizeof(long);
+    emit_insn(ctx, std, LOONGARCH_GPR_S3, LOONGARCH_GPR_SP,
store_offset);
+
+    store_offset -= sizeof(long);
+    emit_insn(ctx, std, LOONGARCH_GPR_S4, LOONGARCH_GPR_SP,
store_offset);
+
+    store_offset -= sizeof(long);
+    emit_insn(ctx, std, LOONGARCH_GPR_S5, LOONGARCH_GPR_SP,
store_offset);
+
+    emit_insn(ctx, addid, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP,
stack_adjust);
+
+    if (bpf_stack_adjust)
+        emit_insn(ctx, addid, regmap[BPF_REG_FP], LOONGARCH_GPR_SP,
bpf_stack_adjust);
+
+    /*
+     * Program contains calls and tail calls, so REG_TCC need
+     * to be saved across calls.
+     */
+    if (seen_tail_call(ctx) && seen_call(ctx))
+        move_reg(ctx, TCC_SAVED, REG_TCC);
+
+    ctx->stack_size = stack_adjust;
+}
+
+static void __build_epilogue(struct jit_ctx *ctx, bool is_tail_call)
+{
+    int stack_adjust = ctx->stack_size;
+    int load_offset;
+
+    load_offset = stack_adjust - sizeof(long);
+    emit_insn(ctx, ldd, LOONGARCH_GPR_RA, LOONGARCH_GPR_SP,
load_offset);
+
+    load_offset -= sizeof(long);
+    emit_insn(ctx, ldd, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP,
load_offset);
+
+    load_offset -= sizeof(long);
+    emit_insn(ctx, ldd, LOONGARCH_GPR_S0, LOONGARCH_GPR_SP,
load_offset);
+
+    load_offset -= sizeof(long);
+    emit_insn(ctx, ldd, LOONGARCH_GPR_S1, LOONGARCH_GPR_SP,
load_offset);
+
+    load_offset -= sizeof(long);
+    emit_insn(ctx, ldd, LOONGARCH_GPR_S2, LOONGARCH_GPR_SP,
load_offset);
+
+    load_offset -= sizeof(long);
+    emit_insn(ctx, ldd, LOONGARCH_GPR_S3, LOONGARCH_GPR_SP,
load_offset);
+
+    load_offset -= sizeof(long);
+    emit_insn(ctx, ldd, LOONGARCH_GPR_S4, LOONGARCH_GPR_SP,
load_offset);
+
+    load_offset -= sizeof(long);
+    emit_insn(ctx, ldd, LOONGARCH_GPR_S5, LOONGARCH_GPR_SP,
load_offset);
+
+    emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP,
stack_adjust);
+
+    if (!is_tail_call) {
+        /* Set return value */
+        move_reg(ctx, LOONGARCH_GPR_A0, regmap[BPF_REG_0]);
+        /* Return to the caller */
+        emit_insn(ctx, jirl, LOONGARCH_GPR_RA, LOONGARCH_GPR_ZERO, 0);
+    } else {
+        /*
+         * Call the next bpf prog and skip the first instruction
+         * of TCC initialization.
+         */
+        emit_insn(ctx, jirl, LOONGARCH_GPR_T3, LOONGARCH_GPR_ZERO, 1);
+    }
+}
+
+void build_epilogue(struct jit_ctx *ctx)
+{
+    __build_epilogue(ctx, false);
+}
+
+bool bpf_jit_supports_kfunc_call(void)
+{
+    return true;
+}
+
+/* initialized on the first pass of build_body() */
+static int out_offset = -1;
+static int emit_bpf_tail_call(struct jit_ctx *ctx)
+{
+    int off;
+    u8 tcc = tail_call_reg(ctx);
+    u8 a1 = LOONGARCH_GPR_A1;
+    u8 a2 = LOONGARCH_GPR_A2;
+    u8 t1 = LOONGARCH_GPR_T1;
+    u8 t2 = LOONGARCH_GPR_T2;
+    u8 t3 = LOONGARCH_GPR_T3;
+    const int idx0 = ctx->idx;
+
+#define cur_offset (ctx->idx - idx0)
+#define jmp_offset (out_offset - (cur_offset))
+
+    /*
+     * a0: &ctx
+     * a1: &array
+     * a2: index
+     *
+     * if (index >= array->map.max_entries)
+     *     goto out;
+     */
+    off = offsetof(struct bpf_array, map.max_entries);
+    emit_insn(ctx, ldwu, t1, a1, off);
+    /* bgeu $a2, $t1, jmp_offset */
+    emit_tailcall_jmp(ctx, BPF_JGE, a2, t1, jmp_offset);
+
+    /*
+     * if (--TCC < 0)
+     *     goto out;
+     */
+    emit_insn(ctx, addid, REG_TCC, tcc, -1);
+    emit_tailcall_jmp(ctx, BPF_JSLT, REG_TCC, LOONGARCH_GPR_ZERO,
jmp_offset);
+
+    /*
+     * prog = array->ptrs[index];
+     * if (!prog)
+     *     goto out;
+     */
+    emit_insn(ctx, sllid, t2, a2, 3);
+    emit_insn(ctx, addd, t2, t2, a1);
+    off = offsetof(struct bpf_array, ptrs);
+    emit_insn(ctx, ldd, t2, t2, off);
+    /* beq $t2, $zero, jmp_offset */
+    emit_tailcall_jmp(ctx, BPF_JEQ, t2, LOONGARCH_GPR_ZERO, jmp_offset);
+
+    /* goto *(prog->bpf_func + 4); */
+    off = offsetof(struct bpf_prog, bpf_func);
+    emit_insn(ctx, ldd, t3, t2, off);
+    __build_epilogue(ctx, true);
+
+    /* out: */
+    if (out_offset == -1)
+        out_offset = cur_offset;
+    if (cur_offset != out_offset) {
+        pr_err_once("tail_call out_offset = %d, expected %d!\n",
+                cur_offset, out_offset);
+        return -1;
+    }
+
+    return 0;
+#undef cur_offset
+#undef jmp_offset
+}
+
+static void emit_atomic(const struct bpf_insn *insn, struct jit_ctx
*ctx)
+{
+    const u8 dst = regmap[insn->dst_reg];
+    const u8 src = regmap[insn->src_reg];
+    const u8 t1 = LOONGARCH_GPR_T1;
+    const u8 t2 = LOONGARCH_GPR_T2;
+    const u8 t3 = LOONGARCH_GPR_T3;
+    const s16 off = insn->off;
+    const s32 imm = insn->imm;
+    const bool isdw = BPF_SIZE(insn->code) == BPF_DW;
+
+    move_imm32(ctx, t1, off, false);
+    emit_insn(ctx, addd, t1, dst, t1);
+    move_reg(ctx, t3, src);
+
+    switch (imm) {
+    /* lock *(size *)(dst + off) <op>= src */
+    case BPF_ADD:
+        if (isdw)
+            emit_insn(ctx, amaddd, t2, t1, src);
+        else
+            emit_insn(ctx, amaddw, t2, t1, src);
+        break;
+    case BPF_AND:
+        if (isdw)
+            emit_insn(ctx, amandd, t2, t1, src);
+        else
+            emit_insn(ctx, amandw, t2, t1, src);
+        break;
+    case BPF_OR:
+        if (isdw)
+            emit_insn(ctx, amord, t2, t1, src);
+        else
+            emit_insn(ctx, amorw, t2, t1, src);
+        break;
+    case BPF_XOR:
+        if (isdw)
+            emit_insn(ctx, amxord, t2, t1, src);
+        else
+            emit_insn(ctx, amxorw, t2, t1, src);
+        break;
+    /* src = atomic_fetch_<op>(dst + off, src) */
+    case BPF_ADD | BPF_FETCH:
+        if (isdw) {
+            emit_insn(ctx, amaddd, src, t1, t3);
+        } else {
+            emit_insn(ctx, amaddw, src, t1, t3);
+            emit_zext_32(ctx, src, true);
+        }
+        break;
+    case BPF_AND | BPF_FETCH:
+        if (isdw) {
+            emit_insn(ctx, amandd, src, t1, t3);
+        } else {
+            emit_insn(ctx, amandw, src, t1, t3);
+            emit_zext_32(ctx, src, true);
+        }
+        break;
+    case BPF_OR | BPF_FETCH:
+        if (isdw) {
+            emit_insn(ctx, amord, src, t1, t3);
+        } else {
+            emit_insn(ctx, amorw, src, t1, t3);
+            emit_zext_32(ctx, src, true);
+        }
+        break;
+    case BPF_XOR | BPF_FETCH:
+        if (isdw) {
+            emit_insn(ctx, amxord, src, t1, t3);
+        } else {
+            emit_insn(ctx, amxorw, src, t1, t3);
+            emit_zext_32(ctx, src, true);
+        }
+        break;
+    /* src = atomic_xchg(dst + off, src); */
+    case BPF_XCHG:
+        if (isdw) {
+            emit_insn(ctx, amswapd, src, t1, t3);
+        } else {
+            emit_insn(ctx, amswapw, src, t1, t3);
+            emit_zext_32(ctx, src, true);
+        }
+        break;
+    /* r0 = atomic_cmpxchg(dst + off, r0, src); */
+    case BPF_CMPXCHG:
+        u8 r0 = regmap[BPF_REG_0];
+
+        move_reg(ctx, t2, r0);
+        if (isdw) {
+            emit_insn(ctx, lld, r0, t1, 0);
+            emit_insn(ctx, bne, t2, r0, 4);
+            move_reg(ctx, t3, src);
+            emit_insn(ctx, scd, t3, t1, 0);
+            emit_insn(ctx, beq, t3, LOONGARCH_GPR_ZERO, -4);
+        } else {
+            emit_insn(ctx, llw, r0, t1, 0);
+            emit_zext_32(ctx, t2, true);
+            emit_zext_32(ctx, r0, true);
+            emit_insn(ctx, bne, t2, r0, 4);
+            move_reg(ctx, t3, src);
+            emit_insn(ctx, scw, t3, t1, 0);
+            emit_insn(ctx, beq, t3, LOONGARCH_GPR_ZERO, -6);
+            emit_zext_32(ctx, r0, true);
+        }
+        break;
+    }
+}
+
+static bool is_signed_bpf_cond(u8 cond)
+{
+    return cond == BPF_JSGT || cond == BPF_JSLT ||
+           cond == BPF_JSGE || cond == BPF_JSLE;
+}
+
+static int build_insn(const struct bpf_insn *insn, struct jit_ctx
*ctx, bool extra_pass)
+{
+    const bool is32 = BPF_CLASS(insn->code) == BPF_ALU ||
+              BPF_CLASS(insn->code) == BPF_JMP32;
+    const u8 code = insn->code;
+    const u8 cond = BPF_OP(code);
+    const u8 dst = regmap[insn->dst_reg];
+    const u8 src = regmap[insn->src_reg];
+    const u8 t1 = LOONGARCH_GPR_T1;
+    const u8 t2 = LOONGARCH_GPR_T2;
+    const s16 off = insn->off;
+    const s32 imm = insn->imm;
+    int i = insn - ctx->prog->insnsi;
+    int jmp_offset;
+
+    switch (code) {
+    /* dst = src */
+    case BPF_ALU | BPF_MOV | BPF_X:
+    case BPF_ALU64 | BPF_MOV | BPF_X:
+        move_reg(ctx, dst, src);
+        emit_zext_32(ctx, dst, is32);
+        break;
+    /* dst = imm */
+    case BPF_ALU | BPF_MOV | BPF_K:
+    case BPF_ALU64 | BPF_MOV | BPF_K:
+        move_imm32(ctx, dst, imm, is32);
+        break;
+
+    /* dst = dst + src */
+    case BPF_ALU | BPF_ADD | BPF_X:
+    case BPF_ALU64 | BPF_ADD | BPF_X:
+        emit_insn(ctx, addd, dst, dst, src);
+        emit_zext_32(ctx, dst, is32);
+        break;
+    /* dst = dst + imm */
+    case BPF_ALU | BPF_ADD | BPF_K:
+    case BPF_ALU64 | BPF_ADD | BPF_K:
+        if (is_signed_imm12(imm)) {
+            emit_insn(ctx, addid, dst, dst, imm);
+        } else {
+            move_imm32(ctx, t1, imm, is32);
+            emit_insn(ctx, addd, dst, dst, t1);
+        }
+        emit_zext_32(ctx, dst, is32);
+        break;
+
+    /* dst = dst - src */
+    case BPF_ALU | BPF_SUB | BPF_X:
+    case BPF_ALU64 | BPF_SUB | BPF_X:
+        emit_insn(ctx, subd, dst, dst, src);
+        emit_zext_32(ctx, dst, is32);
+        break;
+    /* dst = dst - imm */
+    case BPF_ALU | BPF_SUB | BPF_K:
+    case BPF_ALU64 | BPF_SUB | BPF_K:
+        if (is_signed_imm12(-imm)) {
+            emit_insn(ctx, addid, dst, dst, -imm);
+        } else {
+            move_imm32(ctx, t1, imm, is32);
+            emit_insn(ctx, subd, dst, dst, t1);
+        }
+        emit_zext_32(ctx, dst, is32);
+        break;
+
+    /* dst = dst * src */
+    case BPF_ALU | BPF_MUL | BPF_X:
+    case BPF_ALU64 | BPF_MUL | BPF_X:
+        emit_insn(ctx, muld, dst, dst, src);
+        emit_zext_32(ctx, dst, is32);
+        break;
+    /* dst = dst * imm */
+    case BPF_ALU | BPF_MUL | BPF_K:
+    case BPF_ALU64 | BPF_MUL | BPF_K:
+        move_imm32(ctx, t1, imm, is32);
+        emit_insn(ctx, muld, dst, dst, t1);
+        emit_zext_32(ctx, dst, is32);
+        break;
+
+    /* dst = dst / src */
+    case BPF_ALU | BPF_DIV | BPF_X:
+    case BPF_ALU64 | BPF_DIV | BPF_X:
+        emit_zext_32(ctx, dst, is32);
+        move_reg(ctx, t1, src);
+        emit_zext_32(ctx, t1, is32);
+        emit_insn(ctx, divdu, dst, dst, t1);
+        emit_zext_32(ctx, dst, is32);
+        break;
+    /* dst = dst / imm */
+    case BPF_ALU | BPF_DIV | BPF_K:
+    case BPF_ALU64 | BPF_DIV | BPF_K:
+        move_imm32(ctx, t1, imm, is32);
+        emit_zext_32(ctx, dst, is32);
+        emit_insn(ctx, divdu, dst, dst, t1);
+        emit_zext_32(ctx, dst, is32);
+        break;
+
+    /* 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);
+        break;
+    /* dst = dst % imm */
+    case BPF_ALU | BPF_MOD | BPF_K:
+    case BPF_ALU64 | BPF_MOD | BPF_K:
+        move_imm32(ctx, t1, imm, is32);
+        emit_zext_32(ctx, dst, is32);
+        emit_insn(ctx, moddu, dst, dst, t1);
+        emit_zext_32(ctx, dst, is32);
+        break;
+
+    /* dst = -dst */
+    case BPF_ALU | BPF_NEG:
+    case BPF_ALU64 | BPF_NEG:
+        move_imm32(ctx, t1, imm, is32);
+        emit_insn(ctx, subd, dst, LOONGARCH_GPR_ZERO, dst);
+        emit_zext_32(ctx, dst, is32);
+        break;
+
+    /* dst = dst & src */
+    case BPF_ALU | BPF_AND | BPF_X:
+    case BPF_ALU64 | BPF_AND | BPF_X:
+        emit_insn(ctx, and, dst, dst, src);
+        emit_zext_32(ctx, dst, is32);
+        break;
+    /* dst = dst & imm */
+    case BPF_ALU | BPF_AND | BPF_K:
+    case BPF_ALU64 | BPF_AND | BPF_K:
+        if (is_unsigned_imm12(imm)) {
+            emit_insn(ctx, andi, dst, dst, imm);
+        } else {
+            move_imm32(ctx, t1, imm, is32);
+            emit_insn(ctx, and, dst, dst, t1);
+        }
+        emit_zext_32(ctx, dst, is32);
+        break;
+
+    /* dst = dst | src */
+    case BPF_ALU | BPF_OR | BPF_X:
+    case BPF_ALU64 | BPF_OR | BPF_X:
+        emit_insn(ctx, or, dst, dst, src);
+        emit_zext_32(ctx, dst, is32);
+        break;
+    /* dst = dst | imm */
+    case BPF_ALU | BPF_OR | BPF_K:
+    case BPF_ALU64 | BPF_OR | BPF_K:
+        if (is_unsigned_imm12(imm)) {
+            emit_insn(ctx, ori, dst, dst, imm);
+        } else {
+            move_imm32(ctx, t1, imm, is32);
+            emit_insn(ctx, or, dst, dst, t1);
+        }
+        emit_zext_32(ctx, dst, is32);
+        break;
+
+    /* dst = dst ^ src */
+    case BPF_ALU | BPF_XOR | BPF_X:
+    case BPF_ALU64 | BPF_XOR | BPF_X:
+        emit_insn(ctx, xor, dst, dst, src);
+        emit_zext_32(ctx, dst, is32);
+        break;
+    /* dst = dst ^ imm */
+    case BPF_ALU | BPF_XOR | BPF_K:
+    case BPF_ALU64 | BPF_XOR | BPF_K:
+        if (is_unsigned_imm12(imm)) {
+            emit_insn(ctx, xori, dst, dst, imm);
+        } else {
+            move_imm32(ctx, t1, imm, is32);
+            emit_insn(ctx, xor, dst, dst, t1);
+        }
+        emit_zext_32(ctx, dst, is32);
+        break;
+
+    /* dst = dst << src (logical) */
+    case BPF_ALU | BPF_LSH | BPF_X:
+        emit_insn(ctx, sllw, dst, dst, src);
+        emit_zext_32(ctx, dst, is32);
+        break;
+    case BPF_ALU64 | BPF_LSH | BPF_X:
+        emit_insn(ctx, slld, dst, dst, src);
+        break;
+    /* dst = dst << imm (logical) */
+    case BPF_ALU | BPF_LSH | BPF_K:
+        emit_insn(ctx, slliw, dst, dst, imm);
+        emit_zext_32(ctx, dst, is32);
+        break;
+    case BPF_ALU64 | BPF_LSH | BPF_K:
+        emit_insn(ctx, sllid, dst, dst, imm);
+        break;
+
+    /* dst = dst >> src (logical) */
+    case BPF_ALU | BPF_RSH | BPF_X:
+        emit_insn(ctx, srlw, dst, dst, src);
+        emit_zext_32(ctx, dst, is32);
+        break;
+    case BPF_ALU64 | BPF_RSH | BPF_X:
+        emit_insn(ctx, srld, dst, dst, src);
+        break;
+    /* dst = dst >> imm (logical) */
+    case BPF_ALU | BPF_RSH | BPF_K:
+        emit_insn(ctx, srliw, dst, dst, imm);
+        emit_zext_32(ctx, dst, is32);
+        break;
+    case BPF_ALU64 | BPF_RSH | BPF_K:
+        emit_insn(ctx, srlid, dst, dst, imm);
+        break;
+
+    /* dst = dst >> src (arithmetic) */
+    case BPF_ALU | BPF_ARSH | BPF_X:
+        emit_insn(ctx, sraw, dst, dst, src);
+        emit_zext_32(ctx, dst, is32);
+        break;
+    case BPF_ALU64 | BPF_ARSH | BPF_X:
+        emit_insn(ctx, srad, dst, dst, src);
+        break;
+    /* dst = dst >> imm (arithmetic) */
+    case BPF_ALU | BPF_ARSH | BPF_K:
+        emit_insn(ctx, sraiw, dst, dst, imm);
+        emit_zext_32(ctx, dst, is32);
+        break;
+    case BPF_ALU64 | BPF_ARSH | BPF_K:
+        emit_insn(ctx, sraid, dst, dst, imm);
+        break;
+
+    /* dst = BSWAP##imm(dst) */
+    case BPF_ALU | BPF_END | BPF_FROM_LE:
+        switch (imm) {
+        case 16:
+            /* zero-extend 16 bits into 64 bits */
+            emit_insn(ctx, sllid, dst, dst, 48);
+            emit_insn(ctx, srlid, dst, dst, 48);
+            break;
+        case 32:
+            /* zero-extend 32 bits into 64 bits */
+            emit_zext_32(ctx, dst, is32);
+            break;
+        case 64:
+            /* do nothing */
+            break;
+        }
+        break;
+    case BPF_ALU | BPF_END | BPF_FROM_BE:
+        switch (imm) {
+        case 16:
+            emit_insn(ctx, revb2h, dst, dst);
+            /* zero-extend 16 bits into 64 bits */
+            emit_insn(ctx, sllid, dst, dst, 48);
+            emit_insn(ctx, srlid, dst, dst, 48);
+            break;
+        case 32:
+            emit_insn(ctx, revb2w, dst, dst);
+            /* zero-extend 32 bits into 64 bits */
+            emit_zext_32(ctx, dst, is32);
+            break;
+        case 64:
+            emit_insn(ctx, revbd, dst, dst);
+            break;
+        }
+        break;
+
+    /* PC += off if dst cond src */
+    case BPF_JMP | BPF_JEQ | BPF_X:
+    case BPF_JMP | BPF_JNE | BPF_X:
+    case BPF_JMP | BPF_JGT | BPF_X:
+    case BPF_JMP | BPF_JGE | BPF_X:
+    case BPF_JMP | BPF_JLT | BPF_X:
+    case BPF_JMP | BPF_JLE | BPF_X:
+    case BPF_JMP | BPF_JSGT | BPF_X:
+    case BPF_JMP | BPF_JSGE | BPF_X:
+    case BPF_JMP | BPF_JSLT | BPF_X:
+    case BPF_JMP | BPF_JSLE | BPF_X:
+    case BPF_JMP32 | BPF_JEQ | BPF_X:
+    case BPF_JMP32 | BPF_JNE | BPF_X:
+    case BPF_JMP32 | BPF_JGT | BPF_X:
+    case BPF_JMP32 | BPF_JGE | BPF_X:
+    case BPF_JMP32 | BPF_JLT | BPF_X:
+    case BPF_JMP32 | BPF_JLE | BPF_X:
+    case BPF_JMP32 | BPF_JSGT | BPF_X:
+    case BPF_JMP32 | BPF_JSGE | BPF_X:
+    case BPF_JMP32 | BPF_JSLT | BPF_X:
+    case BPF_JMP32 | BPF_JSLE | BPF_X:
+        jmp_offset = bpf2la_offset(i, off, ctx);
+        move_reg(ctx, t1, dst);
+        move_reg(ctx, t2, src);
+        if (is_signed_bpf_cond(BPF_OP(code))) {
+            emit_sext_32(ctx, t1, is32);
+            emit_sext_32(ctx, t2, is32);
+        } else {
+            emit_zext_32(ctx, t1, is32);
+            emit_zext_32(ctx, t2, is32);
+        }
+        emit_cond_jmp(ctx, cond, t1, t2, jmp_offset);
+        break;
+
+    /* PC += off if dst cond imm */
+    case BPF_JMP | BPF_JEQ | BPF_K:
+    case BPF_JMP | BPF_JNE | BPF_K:
+    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:
+    case BPF_JMP | BPF_JSGT | BPF_K:
+    case BPF_JMP | BPF_JSGE | BPF_K:
+    case BPF_JMP | BPF_JSLT | BPF_K:
+    case BPF_JMP | BPF_JSLE | BPF_K:
+    case BPF_JMP32 | BPF_JEQ | BPF_K:
+    case BPF_JMP32 | BPF_JNE | BPF_K:
+    case BPF_JMP32 | BPF_JGT | BPF_K:
+    case BPF_JMP32 | BPF_JGE | BPF_K:
+    case BPF_JMP32 | BPF_JLT | BPF_K:
+    case BPF_JMP32 | BPF_JLE | BPF_K:
+    case BPF_JMP32 | BPF_JSGT | BPF_K:
+    case BPF_JMP32 | BPF_JSGE | BPF_K:
+    case BPF_JMP32 | BPF_JSLT | BPF_K:
+    case BPF_JMP32 | BPF_JSLE | BPF_K:
+        jmp_offset = bpf2la_offset(i, off, ctx);
+        move_imm32(ctx, t1, imm, false);
+        move_reg(ctx, t2, dst);
+        if (is_signed_bpf_cond(BPF_OP(code))) {
+            emit_sext_32(ctx, t1, is32);
+            emit_sext_32(ctx, t2, is32);
+        } else {
+            emit_zext_32(ctx, t1, is32);
+            emit_zext_32(ctx, t2, is32);
+        }
+        emit_cond_jmp(ctx, cond, t2, t1, jmp_offset);
+        break;
+
+    /* PC += off if dst & src */
+    case BPF_JMP | BPF_JSET | BPF_X:
+    case BPF_JMP32 | BPF_JSET | BPF_X:
+        jmp_offset = bpf2la_offset(i, off, ctx);
+        emit_insn(ctx, and, t1, dst, src);
+        emit_zext_32(ctx, t1, is32);
+        emit_cond_jmp(ctx, cond, t1, LOONGARCH_GPR_ZERO, jmp_offset);
+        break;
+    /* PC += off if dst & imm */
+    case BPF_JMP | BPF_JSET | BPF_K:
+    case BPF_JMP32 | BPF_JSET | BPF_K:
+        jmp_offset = bpf2la_offset(i, off, ctx);
+        move_imm32(ctx, t1, imm, is32);
+        emit_insn(ctx, and, t1, dst, t1);
+        emit_zext_32(ctx, t1, is32);
+        emit_cond_jmp(ctx, cond, t1, LOONGARCH_GPR_ZERO, jmp_offset);
+        break;
+
+    /* PC += off */
+    case BPF_JMP | BPF_JA:
+        jmp_offset = bpf2la_offset(i, off, ctx);
+        emit_uncond_jmp(ctx, jmp_offset, is32);
+        break;
+
+    /* function call */
+    case BPF_JMP | BPF_CALL:
+        bool func_addr_fixed;
+        u64 func_addr;
+        int ret;
+
+        mark_call(ctx);
+        ret = bpf_jit_get_func_addr(ctx->prog, insn, extra_pass,
+                        &func_addr, &func_addr_fixed);
+        if (ret < 0)
+            return ret;
+
+        move_imm64(ctx, t1, func_addr, is32);
+        emit_insn(ctx, jirl, t1, LOONGARCH_GPR_RA, 0);
+        move_reg(ctx, regmap[BPF_REG_0], LOONGARCH_GPR_A0);
+        break;
+
+    /* tail call */
+    case BPF_JMP | BPF_TAIL_CALL:
+        mark_tail_call(ctx);
+        if (emit_bpf_tail_call(ctx))
+            return -EINVAL;
+        break;
+
+    /* function return */
+    case BPF_JMP | BPF_EXIT:
+        emit_sext_32(ctx, regmap[BPF_REG_0], true);
+
+        if (i == ctx->prog->len - 1)
+            break;
+
+        jmp_offset = epilogue_offset(ctx);
+        emit_uncond_jmp(ctx, jmp_offset, true);
+        break;
+
+    /* dst = imm64 */
+    case BPF_LD | BPF_IMM | BPF_DW:
+        u64 imm64 = (u64)(insn + 1)->imm << 32 | (u32)insn->imm;
+
+        move_imm64(ctx, dst, imm64, is32);
+        return 1;
+
+    /* dst = *(size *)(src + off) */
+    case BPF_LDX | BPF_MEM | BPF_B:
+    case BPF_LDX | BPF_MEM | BPF_H:
+    case BPF_LDX | BPF_MEM | BPF_W:
+    case BPF_LDX | BPF_MEM | BPF_DW:
+        if (is_signed_imm12(off)) {
+            switch (BPF_SIZE(code)) {
+            case BPF_B:
+                emit_insn(ctx, ldbu, dst, src, off);
+                break;
+            case BPF_H:
+                emit_insn(ctx, ldhu, dst, src, off);
+                break;
+            case BPF_W:
+                emit_insn(ctx, ldwu, dst, src, off);
+                break;
+            case BPF_DW:
+                emit_insn(ctx, ldd, dst, src, off);
+                break;
+            }
+        } else {
+            move_imm32(ctx, t1, off, is32);
+            switch (BPF_SIZE(code)) {
+            case BPF_B:
+                emit_insn(ctx, ldxbu, dst, src, t1);
+                break;
+            case BPF_H:
+                emit_insn(ctx, ldxhu, dst, src, t1);
+                break;
+            case BPF_W:
+                emit_insn(ctx, ldxwu, dst, src, t1);
+                break;
+            case BPF_DW:
+                emit_insn(ctx, ldxd, dst, src, t1);
+                break;
+            }
+        }
+        break;
+
+    /* *(size *)(dst + off) = imm */
+    case BPF_ST | BPF_MEM | BPF_B:
+    case BPF_ST | BPF_MEM | BPF_H:
+    case BPF_ST | BPF_MEM | BPF_W:
+    case BPF_ST | BPF_MEM | BPF_DW:
+        move_imm32(ctx, t1, imm, is32);
+        if (is_signed_imm12(off)) {
+            switch (BPF_SIZE(code)) {
+            case BPF_B:
+                emit_insn(ctx, stb, t1, dst, off);
+                break;
+            case BPF_H:
+                emit_insn(ctx, sth, t1, dst, off);
+                break;
+            case BPF_W:
+                emit_insn(ctx, stw, t1, dst, off);
+                break;
+            case BPF_DW:
+                emit_insn(ctx, std, t1, dst, off);
+                break;
+            }
+        } else {
+            move_imm32(ctx, t2, off, is32);
+            switch (BPF_SIZE(code)) {
+            case BPF_B:
+                emit_insn(ctx, stxb, t1, dst, t2);
+                break;
+            case BPF_H:
+                emit_insn(ctx, stxh, t1, dst, t2);
+                break;
+            case BPF_W:
+                emit_insn(ctx, stxw, t1, dst, t2);
+                break;
+            case BPF_DW:
+                emit_insn(ctx, stxd, t1, dst, t2);
+                break;
+            }
+        }
+        break;
+
+    /* *(size *)(dst + off) = src */
+    case BPF_STX | BPF_MEM | BPF_B:
+    case BPF_STX | BPF_MEM | BPF_H:
+    case BPF_STX | BPF_MEM | BPF_W:
+    case BPF_STX | BPF_MEM | BPF_DW:
+        if (is_signed_imm12(off)) {
+            switch (BPF_SIZE(code)) {
+            case BPF_B:
+                emit_insn(ctx, stb, src, dst, off);
+                break;
+            case BPF_H:
+                emit_insn(ctx, sth, src, dst, off);
+                break;
+            case BPF_W:
+                emit_insn(ctx, stw, src, dst, off);
+                break;
+            case BPF_DW:
+                emit_insn(ctx, std, src, dst, off);
+                break;
+            }
+        } else {
+            move_imm32(ctx, t1, off, is32);
+            switch (BPF_SIZE(code)) {
+            case BPF_B:
+                emit_insn(ctx, stxb, src, dst, t1);
+                break;
+            case BPF_H:
+                emit_insn(ctx, stxh, src, dst, t1);
+                break;
+            case BPF_W:
+                emit_insn(ctx, stxw, src, dst, t1);
+                break;
+            case BPF_DW:
+                emit_insn(ctx, stxd, src, dst, t1);
+                break;
+            }
+        }
+        break;
+
+    case BPF_STX | BPF_ATOMIC | BPF_W:
+    case BPF_STX | BPF_ATOMIC | BPF_DW:
+        emit_atomic(insn, ctx);
+        break;
+
+    default:
+        pr_err("bpf_jit: unknown opcode %02x\n", code);
+        return -EINVAL;
+    }
+
+    return 0;
+}
+
+static int build_body(struct jit_ctx *ctx, bool extra_pass)
+{
+    const struct bpf_prog *prog = ctx->prog;
+    int i;
+
+    for (i = 0; i < prog->len; i++) {
+        const struct bpf_insn *insn = &prog->insnsi[i];
+        int ret;
+
+        if (ctx->image == NULL)
+            ctx->offset[i] = ctx->idx;
+
+        ret = build_insn(insn, ctx, extra_pass);
+        if (ret > 0) {
+            i++;
+            if (ctx->image == NULL)
+                ctx->offset[i] = ctx->idx;
+            continue;
+        }
+        if (ret)
+            return ret;
+    }
+
+    if (ctx->image == NULL)
+        ctx->offset[i] = ctx->idx;
+
+    return 0;
+}
+
+static inline void bpf_flush_icache(void *start, void *end)
+{
+    flush_icache_range((unsigned long)start, (unsigned long)end);
+}
+
+/* Fill space with illegal instructions */
+static void jit_fill_hole(void *area, unsigned int size)
+{
+    u32 *ptr;
+
+    /* We are guaranteed to have aligned memory */
+    for (ptr = area; size >= sizeof(u32); size -= sizeof(u32))
+        *ptr++ = INSN_BREAK;
+}
+
+static int validate_code(struct jit_ctx *ctx)
+{
+    int i;
+    union loongarch_instruction insn;
+
+    for (i = 0; i < ctx->idx; i++) {
+        insn = ctx->image[i];
+        /* Check INSN_BREAK */
+        if (insn.word == INSN_BREAK)
+            return -1;
+    }
+
+    return 0;
+}
+
+struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
+{
+    struct bpf_prog *tmp, *orig_prog = prog;
+    struct bpf_binary_header *header;
+    struct jit_data *jit_data;
+    struct jit_ctx ctx;
+    bool tmp_blinded = false;
+    bool extra_pass = false;
+    int image_size;
+    u8 *image_ptr;
+
+    /*
+     * If BPF JIT was not enabled then we must fall back to
+     * the interpreter.
+     */
+    if (!prog->jit_requested)
+        return orig_prog;
+
+    tmp = bpf_jit_blind_constants(prog);
+    /*
+     * If blinding was requested and we failed during blinding,
+     * we must fall back to the interpreter. Otherwise, we save
+     * the new JITed code.
+     */
+    if (IS_ERR(tmp))
+        return orig_prog;
+    if (tmp != prog) {
+        tmp_blinded = true;
+        prog = tmp;
+    }
+
+    jit_data = prog->aux->jit_data;
+    if (!jit_data) {
+        jit_data = kzalloc(sizeof(*jit_data), GFP_KERNEL);
+        if (!jit_data) {
+            prog = orig_prog;
+            goto out;
+        }
+        prog->aux->jit_data = jit_data;
+    }
+    if (jit_data->ctx.offset) {
+        ctx = jit_data->ctx;
+        image_ptr = jit_data->image;
+        header = jit_data->header;
+        extra_pass = true;
+        image_size = sizeof(u32) * ctx.idx;
+        goto skip_init_ctx;
+    }
+
+    memset(&ctx, 0, sizeof(ctx));
+    ctx.prog = prog;
+
+    ctx.offset = kcalloc(prog->len + 1, sizeof(u32), GFP_KERNEL);
+    if (ctx.offset == NULL) {
+        prog = orig_prog;
+        goto out_off;
+    }
+
+    /* 1. Initial fake pass to compute ctx->idx and set ctx->flags */
+    if (build_body(&ctx, extra_pass)) {
+        prog = orig_prog;
+        goto out_off;
+    }
+    build_prologue(&ctx);
+    ctx.epilogue_offset = ctx.idx;
+    build_epilogue(&ctx);
+
+    /* Now we know the actual image size.
+     * As each LoongArch instruction is of length 32bit,
+     * we are translating number of JITed intructions into
+     * the size required to store these JITed code.
+     */
+    image_size = sizeof(u32) * ctx.idx;
+    /* Now we know the size of the structure to make */
+    header = bpf_jit_binary_alloc(image_size, &image_ptr,
+                      sizeof(u32), jit_fill_hole);
+    if (header == NULL) {
+        prog = orig_prog;
+        goto out_off;
+    }
+
+    /* 2. Now, the actual pass to generate final JIT code */
+    ctx.image = (union loongarch_instruction *)image_ptr;
+skip_init_ctx:
+    ctx.idx = 0;
+
+    build_prologue(&ctx);
+    if (build_body(&ctx, extra_pass)) {
+        bpf_jit_binary_free(header);
+        prog = orig_prog;
+        goto out_off;
+    }
+    build_epilogue(&ctx);
+
+    /* 3. Extra pass to validate JITed code */
+    if (validate_code(&ctx)) {
+        bpf_jit_binary_free(header);
+        prog = orig_prog;
+        goto out_off;
+    }
+
+    /* And we're done */
+    if (bpf_jit_enable > 1)
+        bpf_jit_dump(prog->len, image_size, 2, ctx.image);
+
+    /* Update the icache */
+    bpf_flush_icache(header, ctx.image + ctx.idx);
+
+    if (!prog->is_func || extra_pass) {
+        if (extra_pass && ctx.idx != jit_data->ctx.idx) {
+            pr_err_once("multi-func JIT bug %d != %d\n",
+                    ctx.idx, jit_data->ctx.idx);
+            bpf_jit_binary_free(header);
+            prog->bpf_func = NULL;
+            prog->jited = 0;
+            prog->jited_len = 0;
+            goto out_off;
+        }
+        bpf_jit_binary_lock_ro(header);
+    } else {
+        jit_data->ctx = ctx;
+        jit_data->image = image_ptr;
+        jit_data->header = header;
+    }
+    prog->bpf_func = (void *)ctx.image;
+    prog->jited = 1;
+    prog->jited_len = image_size;
+
+    if (!prog->is_func || extra_pass) {
+out_off:
+        kfree(ctx.offset);
+        kfree(jit_data);
+        prog->aux->jit_data = NULL;
+    }
+out:
+    if (tmp_blinded)
+        bpf_jit_prog_release_other(prog, prog == orig_prog ?
+                       tmp : orig_prog);
+
+    out_offset = -1;
+    return prog;
+}
diff --git a/arch/loongarch/net/bpf_jit.h b/arch/loongarch/net/bpf_jit.h
new file mode 100644
index 0000000..9c735f3
--- /dev/null
+++ b/arch/loongarch/net/bpf_jit.h
@@ -0,0 +1,308 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * BPF JIT compiler for LoongArch
+ *
+ * Copyright (C) 2022 Loongson Technology Corporation Limited
+ */
+#include <linux/bpf.h>
+#include <linux/filter.h>
+#include <asm/cacheflush.h>
+#include <asm/inst.h>
+
+struct jit_ctx {
+    const struct bpf_prog *prog;
+    unsigned int idx;
+    unsigned int flags;
+    unsigned int epilogue_offset;
+    u32 *offset;
+    union loongarch_instruction *image;
+    u32 stack_size;
+};
+
+struct jit_data {
+    struct bpf_binary_header *header;
+    u8 *image;
+    struct jit_ctx ctx;
+};
+
+#define emit_insn(ctx, func, ...)                        \
+do {                                        \
+    if (ctx->image != NULL) {                        \
+        union loongarch_instruction *insn = &ctx->image[ctx->idx];    \
+        emit_##func(insn, ##__VA_ARGS__);                \
+    }                                    \
+    ctx->idx++;                                \
+} while (0)
+
+#define is_signed_imm12(val)    signed_imm_check(val, 12)
+#define is_signed_imm16(val)    signed_imm_check(val, 16)
+#define is_signed_imm26(val)    signed_imm_check(val, 26)
+#define is_signed_imm32(val)    signed_imm_check(val, 32)
+#define is_signed_imm52(val)    signed_imm_check(val, 52)
+#define is_unsigned_imm12(val)    unsigned_imm_check(val, 12)
+
+static inline int bpf2la_offset(int bpf_insn, int off, const struct
jit_ctx *ctx)
+{
+    /* BPF JMP offset is relative to the next instruction */
+    bpf_insn++;
+    /*
+     * Whereas loongarch branch instructions encode the offset
+     * from the branch itself, so we must subtract 1 from the
+     * instruction offset.
+     */
+    return (ctx->offset[bpf_insn + off] - (ctx->offset[bpf_insn] - 1));
+}
+
+static inline int epilogue_offset(const struct jit_ctx *ctx)
+{
+    int to = ctx->epilogue_offset;
+    int from = ctx->idx;
+
+    return (to - from);
+}
+
+/* Zero-extend 32 bits into 64 bits */
+static inline void emit_zext_32(struct jit_ctx *ctx, enum
loongarch_gpr reg, bool is32)
+{
+    if (!is32)
+        return;
+
+    emit_insn(ctx, lu32id, reg, 0);
+}
+
+/* Signed-extend 32 bits into 64 bits */
+static inline void emit_sext_32(struct jit_ctx *ctx, enum
loongarch_gpr reg, bool is32)
+{
+    if (!is32)
+        return;
+
+    emit_insn(ctx, addiw, reg, reg, 0);
+}
+
+static inline void move_imm32(struct jit_ctx *ctx, enum loongarch_gpr
rd,
+                  int imm32, bool is32)
+{
+    int si20;
+    u32 ui12;
+
+    /* or rd, $zero, $zero */
+    if (imm32 == 0) {
+        emit_insn(ctx, or, rd, LOONGARCH_GPR_ZERO, LOONGARCH_GPR_ZERO);
+        return;
+    }
+
+    /* addiw rd, $zero, imm_11_0(signed) */
+    if (is_signed_imm12(imm32)) {
+        emit_insn(ctx, addiw, rd, LOONGARCH_GPR_ZERO, imm32);
+        goto zext;
+    }
+
+    /* ori rd, $zero, imm_11_0(unsigned) */
+    if (is_unsigned_imm12(imm32)) {
+        emit_insn(ctx, ori, rd, LOONGARCH_GPR_ZERO, imm32);
+        goto zext;
+    }
+
+    /* lu12iw rd, imm_31_12(signed) */
+    si20 = (imm32 >> 12) & 0xfffff;
+    emit_insn(ctx, lu12iw, rd, si20);
+
+    /* ori rd, rd, imm_11_0(unsigned) */
+    ui12 = imm32 & 0xfff;
+    if (ui12 != 0)
+        emit_insn(ctx, ori, rd, rd, ui12);
+
+zext:
+    emit_zext_32(ctx, rd, is32);
+}
+
+static inline void move_imm64(struct jit_ctx *ctx, enum loongarch_gpr
rd,
+                  long imm64, bool is32)
+{
+    int imm32, si20, si12;
+    long imm52;
+
+    si12 = (imm64 >> 52) & 0xfff;
+    imm52 = imm64 & 0xfffffffffffff;
+    /* lu52id rd, $zero, imm_63_52(signed) */
+    if (si12 != 0 && imm52 == 0) {
+        emit_insn(ctx, lu52id, rd, LOONGARCH_GPR_ZERO, si12);
+        return;
+    }
+
+    imm32 = imm64 & 0xffffffff;
+    move_imm32(ctx, rd, imm32, is32);
+
+    if (!is_signed_imm32(imm64)) {
+        if (imm52 != 0) {
+            /* lu32id rd, imm_51_32(signed) */
+            si20 = (imm64 >> 32) & 0xfffff;
+            emit_insn(ctx, lu32id, rd, si20);
+        }
+
+        /* lu52id rd, rd, imm_63_52(signed) */
+        if (!is_signed_imm52(imm64))
+            emit_insn(ctx, lu52id, rd, rd, si12);
+    }
+}
+
+static inline void move_reg(struct jit_ctx *ctx, enum loongarch_gpr rd,
+                enum loongarch_gpr rj)
+{
+    emit_insn(ctx, or, rd, rj, LOONGARCH_GPR_ZERO);
+}
+
+static inline int invert_jmp_cond(u8 cond)
+{
+    switch (cond) {
+    case BPF_JEQ:
+        return BPF_JNE;
+    case BPF_JNE:
+    case BPF_JSET:
+        return BPF_JEQ;
+    case BPF_JGT:
+        return BPF_JLE;
+    case BPF_JGE:
+        return BPF_JLT;
+    case BPF_JLT:
+        return BPF_JGE;
+    case BPF_JLE:
+        return BPF_JGT;
+    case BPF_JSGT:
+        return BPF_JSLE;
+    case BPF_JSGE:
+        return BPF_JSLT;
+    case BPF_JSLT:
+        return BPF_JSGE;
+    case BPF_JSLE:
+        return BPF_JSGT;
+    }
+    return -1;
+}
+
+static inline void cond_jmp_offs16(struct jit_ctx *ctx, u8 cond, enum
loongarch_gpr rj,
+                   enum loongarch_gpr rd, int jmp_offset)
+{
+    switch (cond) {
+    case BPF_JEQ:
+        /* PC += jmp_offset if rj == rd */
+        emit_insn(ctx, beq, rj, rd, jmp_offset);
+        return;
+    case BPF_JNE:
+    case BPF_JSET:
+        /* PC += jmp_offset if rj != rd */
+        emit_insn(ctx, bne, rj, rd, jmp_offset);
+        return;
+    case BPF_JGT:
+        /* PC += jmp_offset if rj > rd (unsigned) */
+        emit_insn(ctx, bltu, rd, rj, jmp_offset);
+        return;
+    case BPF_JLT:
+        /* PC += jmp_offset if rj < rd (unsigned) */
+        emit_insn(ctx, bltu, rj, rd, jmp_offset);
+        return;
+    case BPF_JGE:
+        /* PC += jmp_offset if rj >= rd (unsigned) */
+        emit_insn(ctx, bgeu, rj, rd, jmp_offset);
+        return;
+    case BPF_JLE:
+        /* PC += jmp_offset if rj <= rd (unsigned) */
+        emit_insn(ctx, bgeu, rd, rj, jmp_offset);
+        return;
+    case BPF_JSGT:
+        /* PC += jmp_offset if rj > rd (signed) */
+        emit_insn(ctx, blt, rd, rj, jmp_offset);
+        return;
+    case BPF_JSLT:
+        /* PC += jmp_offset if rj < rd (signed) */
+        emit_insn(ctx, blt, rj, rd, jmp_offset);
+        return;
+    case BPF_JSGE:
+        /* PC += jmp_offset if rj >= rd (signed) */
+        emit_insn(ctx, bge, rj, rd, jmp_offset);
+        return;
+    case BPF_JSLE:
+        /* PC += jmp_offset if rj <= rd (signed) */
+        emit_insn(ctx, bge, rd, rj, jmp_offset);
+        return;
+    }
+}
+
+static inline void cond_jmp_offs26(struct jit_ctx *ctx, u8 cond, enum
loongarch_gpr rj,
+                   enum loongarch_gpr rd, int jmp_offset)
+{
+    cond = invert_jmp_cond(cond);
+    cond_jmp_offs16(ctx, cond, rj, rd, 2);
+    emit_insn(ctx, b, jmp_offset);
+}
+
+static inline void cond_jmp_offs32(struct jit_ctx *ctx, u8 cond, enum
loongarch_gpr rj,
+                   enum loongarch_gpr rd, int jmp_offset)
+{
+    s64 upper, lower;
+
+    upper = (jmp_offset + (1 << 15)) >> 16;
+    lower = jmp_offset & 0xffff;
+
+    cond = invert_jmp_cond(cond);
+    cond_jmp_offs16(ctx, cond, rj, rd, 3);
+
+    /*
+     * jmp_addr = jmp_offset << 2
+     * tmp2 = PC + jmp_addr[31, 18] + 18'b0
+     */
+    emit_insn(ctx, pcaddu18i, LOONGARCH_GPR_T2, upper << 2);
+
+    /* jump to (tmp2 + jmp_addr[17, 2] + 2'b0) */
+    emit_insn(ctx, jirl, LOONGARCH_GPR_T2, LOONGARCH_GPR_ZERO, lower
+ 1);
+}
+
+static inline void uncond_jmp_offs26(struct jit_ctx *ctx, int
jmp_offset)
+{
+    emit_insn(ctx, b, jmp_offset);
+}
+
+static inline void uncond_jmp_offs32(struct jit_ctx *ctx, int
jmp_offset, bool is_exit)
+{
+    s64 upper, lower;
+
+    upper = (jmp_offset + (1 << 15)) >> 16;
+    lower = jmp_offset & 0xffff;
+
+    if (is_exit)
+        lower -= 1;
+
+    /*
+     * jmp_addr = jmp_offset << 2;
+     * tmp1 = PC + jmp_addr[31, 18] + 18'b0
+     */
+    emit_insn(ctx, pcaddu18i, LOONGARCH_GPR_T1, upper << 2);
+
+    /* jump to (tmp1 + jmp_addr[17, 2] + 2'b0) */
+    emit_insn(ctx, jirl, LOONGARCH_GPR_T1, LOONGARCH_GPR_ZERO, lower
+ 1);
+}
+
+static inline void emit_cond_jmp(struct jit_ctx *ctx, u8 cond, enum
loongarch_gpr rj,
+                 enum loongarch_gpr rd, int jmp_offset)
+{
+    cond_jmp_offs26(ctx, cond, rj, rd, jmp_offset);
+}
+
+static inline void emit_uncond_jmp(struct jit_ctx *ctx, int
jmp_offset, bool is_exit)
+{
+    if (is_signed_imm26(jmp_offset))
+        uncond_jmp_offs26(ctx, jmp_offset);
+    else
+        uncond_jmp_offs32(ctx, jmp_offset, is_exit);
+}
+
+static inline void emit_tailcall_jmp(struct jit_ctx *ctx, u8 cond,
enum loongarch_gpr rj,
+                     enum loongarch_gpr rd, int jmp_offset)
+{
+    if (is_signed_imm16(jmp_offset))
+        cond_jmp_offs16(ctx, cond, rj, rd, jmp_offset);
+    else if (is_signed_imm26(jmp_offset))
+        cond_jmp_offs26(ctx, cond, rj, rd, jmp_offset - 1);
+    else
+        cond_jmp_offs32(ctx, cond, rj, rd, jmp_offset - 2);
+}





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