[openwrt/openwrt] kernel: backport a rewrite of the mips eBPF JIT implementation

LEDE Commits lede-commits at lists.infradead.org
Thu Oct 14 11:30:07 PDT 2021


nbd pushed a commit to openwrt/openwrt.git, branch master:
https://git.openwrt.org/f2e1e156c0b64b7fae72940c0895b30266729b1e

commit f2e1e156c0b64b7fae72940c0895b30266729b1e
Author: Felix Fietkau <nbd at nbd.name>
AuthorDate: Wed Oct 13 17:49:31 2021 +0200

    kernel: backport a rewrite of the mips eBPF JIT implementation
    
    This adds support for eBPF JIT for 32 bit targets and significantly improves
    correctness.
    
    Signed-off-by: Felix Fietkau <nbd at nbd.name>
---
 ...-MIPS-uasm-Enable-muhu-opcode-for-MIPS-R6.patch |   65 +
 ...dd-workaround-for-Loongson-2F-nop-CPU-err.patch |   31 +
 ...-02-mips-bpf-Add-eBPF-JIT-for-32-bit-MIPS.patch | 3078 ++++++++++++++++++++
 ...mips-bpf-Add-new-eBPF-JIT-for-64-bit-MIPS.patch | 1005 +++++++
 ...ps-bpf-Add-JIT-workarounds-for-CPU-errata.patch |  120 +
 .../050-v5.16-05-mips-bpf-Enable-eBPF-JITs.patch   |   61 +
 ...ps-bpf-Remove-old-BPF-JIT-implementations.patch |  387 +++
 ...lect-CPU_MIPS64-for-remaining-MIPS64-CPUs.patch |    2 +-
 ...-MIPS-uasm-Enable-muhu-opcode-for-MIPS-R6.patch |   65 +
 ...dd-workaround-for-Loongson-2F-nop-CPU-err.patch |   31 +
 ...-02-mips-bpf-Add-eBPF-JIT-for-32-bit-MIPS.patch | 3078 ++++++++++++++++++++
 ...mips-bpf-Add-new-eBPF-JIT-for-64-bit-MIPS.patch | 1005 +++++++
 ...ps-bpf-Add-JIT-workarounds-for-CPU-errata.patch |  120 +
 .../071-v5.16-05-mips-bpf-Enable-eBPF-JITs.patch   |   54 +
 ...ps-bpf-Remove-old-BPF-JIT-implementations.patch |  387 +++
 ...-0072-net-WireGuard-secure-network-tunnel.patch |    2 +-
 .../hack-5.10/301-mips_image_cmdline_hack.patch    |    2 +-
 .../hack-5.4/301-mips_image_cmdline_hack.patch     |    2 +-
 .../pending-5.10/300-mips_expose_boot_raw.patch    |    4 +-
 ...lect-CPU_MIPS64-for-remaining-MIPS64-CPUs.patch |    2 +-
 .../pending-5.4/300-mips_expose_boot_raw.patch     |    4 +-
 .../0122-mips-ralink-enable-zboot-support.patch    |    2 +-
 22 files changed, 9497 insertions(+), 10 deletions(-)

diff --git a/target/linux/generic/backport-5.10/050-v5.16-00-MIPS-uasm-Enable-muhu-opcode-for-MIPS-R6.patch b/target/linux/generic/backport-5.10/050-v5.16-00-MIPS-uasm-Enable-muhu-opcode-for-MIPS-R6.patch
new file mode 100644
index 0000000000..82feb7421d
--- /dev/null
+++ b/target/linux/generic/backport-5.10/050-v5.16-00-MIPS-uasm-Enable-muhu-opcode-for-MIPS-R6.patch
@@ -0,0 +1,65 @@
+From: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+Date: Tue, 5 Oct 2021 18:54:02 +0200
+Subject: [PATCH] MIPS: uasm: Enable muhu opcode for MIPS R6
+
+Enable the 'muhu' instruction, complementing the existing 'mulu', needed
+to implement a MIPS32 BPF JIT.
+
+Also fix a typo in the existing definition of 'dmulu'.
+
+Signed-off-by: Tony Ambardar <Tony.Ambardar at gmail.com>
+
+This patch is a dependency for my 32-bit MIPS eBPF JIT.
+
+Signed-off-by: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+---
+
+--- a/arch/mips/include/asm/uasm.h
++++ b/arch/mips/include/asm/uasm.h
+@@ -145,6 +145,7 @@ Ip_u1(_mtlo);
+ Ip_u3u1u2(_mul);
+ Ip_u1u2(_multu);
+ Ip_u3u1u2(_mulu);
++Ip_u3u1u2(_muhu);
+ Ip_u3u1u2(_nor);
+ Ip_u3u1u2(_or);
+ Ip_u2u1u3(_ori);
+--- a/arch/mips/mm/uasm-mips.c
++++ b/arch/mips/mm/uasm-mips.c
+@@ -90,7 +90,7 @@ static const struct insn insn_table[insn
+ 				RS | RT | RD},
+ 	[insn_dmtc0]	= {M(cop0_op, dmtc_op, 0, 0, 0, 0), RT | RD | SET},
+ 	[insn_dmultu]	= {M(spec_op, 0, 0, 0, 0, dmultu_op), RS | RT},
+-	[insn_dmulu]	= {M(spec_op, 0, 0, 0, dmult_dmul_op, dmultu_op),
++	[insn_dmulu]	= {M(spec_op, 0, 0, 0, dmultu_dmulu_op, dmultu_op),
+ 				RS | RT | RD},
+ 	[insn_drotr]	= {M(spec_op, 1, 0, 0, 0, dsrl_op), RT | RD | RE},
+ 	[insn_drotr32]	= {M(spec_op, 1, 0, 0, 0, dsrl32_op), RT | RD | RE},
+@@ -150,6 +150,8 @@ static const struct insn insn_table[insn
+ 	[insn_mtlo]	= {M(spec_op, 0, 0, 0, 0, mtlo_op), RS},
+ 	[insn_mulu]	= {M(spec_op, 0, 0, 0, multu_mulu_op, multu_op),
+ 				RS | RT | RD},
++	[insn_muhu]	= {M(spec_op, 0, 0, 0, multu_muhu_op, multu_op),
++				RS | RT | RD},
+ #ifndef CONFIG_CPU_MIPSR6
+ 	[insn_mul]	= {M(spec2_op, 0, 0, 0, 0, mul_op), RS | RT | RD},
+ #else
+--- a/arch/mips/mm/uasm.c
++++ b/arch/mips/mm/uasm.c
+@@ -59,7 +59,7 @@ enum opcode {
+ 	insn_lddir, insn_ldpte, insn_ldx, insn_lh, insn_lhu, insn_ll, insn_lld,
+ 	insn_lui, insn_lw, insn_lwu, insn_lwx, insn_mfc0, insn_mfhc0, insn_mfhi,
+ 	insn_mflo, insn_modu, insn_movn, insn_movz, insn_mtc0, insn_mthc0,
+-	insn_mthi, insn_mtlo, insn_mul, insn_multu, insn_mulu, insn_nor,
++	insn_mthi, insn_mtlo, insn_mul, insn_multu, insn_mulu, insn_muhu, insn_nor,
+ 	insn_or, insn_ori, insn_pref, insn_rfe, insn_rotr, insn_sb, insn_sc,
+ 	insn_scd, insn_seleqz, insn_selnez, insn_sd, insn_sh, insn_sll,
+ 	insn_sllv, insn_slt, insn_slti, insn_sltiu, insn_sltu, insn_sra,
+@@ -344,6 +344,7 @@ I_u1(_mtlo)
+ I_u3u1u2(_mul)
+ I_u1u2(_multu)
+ I_u3u1u2(_mulu)
++I_u3u1u2(_muhu)
+ I_u3u1u2(_nor)
+ I_u3u1u2(_or)
+ I_u2u1u3(_ori)
diff --git a/target/linux/generic/backport-5.10/050-v5.16-01-mips-uasm-Add-workaround-for-Loongson-2F-nop-CPU-err.patch b/target/linux/generic/backport-5.10/050-v5.16-01-mips-uasm-Add-workaround-for-Loongson-2F-nop-CPU-err.patch
new file mode 100644
index 0000000000..3a4d573f80
--- /dev/null
+++ b/target/linux/generic/backport-5.10/050-v5.16-01-mips-uasm-Add-workaround-for-Loongson-2F-nop-CPU-err.patch
@@ -0,0 +1,31 @@
+From: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+Date: Tue, 5 Oct 2021 18:54:03 +0200
+Subject: [PATCH] mips: uasm: Add workaround for Loongson-2F nop CPU errata
+
+This patch implements a workaround for the Loongson-2F nop in generated,
+code, if the existing option CONFIG_CPU_NOP_WORKAROUND is set. Before,
+the binutils option -mfix-loongson2f-nop was enabled, but no workaround
+was done when emitting MIPS code. Now, the nop pseudo instruction is
+emitted as "or ax,ax,zero" instead of the default "sll zero,zero,0". This
+is consistent with the workaround implemented by binutils.
+
+Link: https://sourceware.org/legacy-ml/binutils/2009-11/msg00387.html
+
+Signed-off-by: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+Reviewed-by: Jiaxun Yang <jiaxun.yang at flygoat.com>
+---
+
+--- a/arch/mips/include/asm/uasm.h
++++ b/arch/mips/include/asm/uasm.h
+@@ -249,7 +249,11 @@ static inline void uasm_l##lb(struct uas
+ #define uasm_i_bnezl(buf, rs, off) uasm_i_bnel(buf, rs, 0, off)
+ #define uasm_i_ehb(buf) uasm_i_sll(buf, 0, 0, 3)
+ #define uasm_i_move(buf, a, b) UASM_i_ADDU(buf, a, 0, b)
++#ifdef CONFIG_CPU_NOP_WORKAROUNDS
++#define uasm_i_nop(buf) uasm_i_or(buf, 1, 1, 0)
++#else
+ #define uasm_i_nop(buf) uasm_i_sll(buf, 0, 0, 0)
++#endif
+ #define uasm_i_ssnop(buf) uasm_i_sll(buf, 0, 0, 1)
+ 
+ static inline void uasm_i_drotr_safe(u32 **p, unsigned int a1,
diff --git a/target/linux/generic/backport-5.10/050-v5.16-02-mips-bpf-Add-eBPF-JIT-for-32-bit-MIPS.patch b/target/linux/generic/backport-5.10/050-v5.16-02-mips-bpf-Add-eBPF-JIT-for-32-bit-MIPS.patch
new file mode 100644
index 0000000000..7980659961
--- /dev/null
+++ b/target/linux/generic/backport-5.10/050-v5.16-02-mips-bpf-Add-eBPF-JIT-for-32-bit-MIPS.patch
@@ -0,0 +1,3078 @@
+From: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+Date: Tue, 5 Oct 2021 18:54:04 +0200
+Subject: [PATCH] mips: bpf: Add eBPF JIT for 32-bit MIPS
+
+This is an implementation of an eBPF JIT for 32-bit MIPS I-V and MIPS32.
+The implementation supports all 32-bit and 64-bit ALU and JMP operations,
+including the recently-added atomics. 64-bit div/mod and 64-bit atomics
+are implemented using function calls to math64 and atomic64 functions,
+respectively. All 32-bit operations are implemented natively by the JIT,
+except if the CPU lacks ll/sc instructions.
+
+Register mapping
+================
+All 64-bit eBPF registers are mapped to native 32-bit MIPS register pairs,
+and does not use any stack scratch space for register swapping. This means
+that all eBPF register data is kept in CPU registers all the time, and
+this simplifies the register management a lot. It also reduces the JIT's
+pressure on temporary registers since we do not have to move data around.
+
+Native register pairs are ordered according to CPU endiannes, following
+the O32 calling convention for passing 64-bit arguments and return values.
+The eBPF return value, arguments and callee-saved registers are mapped to
+their native MIPS equivalents.
+
+Since the 32 highest bits in the eBPF FP (frame pointer) register are
+always zero, only one general-purpose register is actually needed for the
+mapping. The MIPS fp register is used for this purpose. The high bits are
+mapped to MIPS register r0. This saves us one CPU register, which is much
+needed for temporaries, while still allowing us to treat the R10 (FP)
+register just like any other eBPF register in the JIT.
+
+The MIPS gp (global pointer) and at (assembler temporary) registers are
+used as internal temporary registers for constant blinding. CPU registers
+t6-t9 are used internally by the JIT when constructing more complex 64-bit
+operations. This is precisely what is needed - two registers to store an
+operand value, and two more as scratch registers when performing the
+operation.
+
+The register mapping is shown below.
+
+    R0 - $v1, $v0   return value
+    R1 - $a1, $a0   argument 1, passed in registers
+    R2 - $a3, $a2   argument 2, passed in registers
+    R3 - $t1, $t0   argument 3, passed on stack
+    R4 - $t3, $t2   argument 4, passed on stack
+    R5 - $t4, $t3   argument 5, passed on stack
+    R6 - $s1, $s0   callee-saved
+    R7 - $s3, $s2   callee-saved
+    R8 - $s5, $s4   callee-saved
+    R9 - $s7, $s6   callee-saved
+    FP - $r0, $fp   32-bit frame pointer
+    AX - $gp, $at   constant-blinding
+         $t6 - $t9  unallocated, JIT temporaries
+
+Jump offsets
+============
+The JIT tries to map all conditional JMP operations to MIPS conditional
+PC-relative branches. The MIPS branch offset field is 18 bits, in bytes,
+which is equivalent to the eBPF 16-bit instruction offset. However, since
+the JIT may emit more than one CPU instruction per eBPF instruction, the
+field width may overflow. If that happens, the JIT converts the long
+conditional jump to a short PC-relative branch with the condition
+inverted, jumping over a long unconditional absolute jmp (j).
+
+This conversion will change the instruction offset mapping used for jumps,
+and may in turn result in more branch offset overflows. The JIT therefore
+dry-runs the translation until no more branches are converted and the
+offsets do not change anymore. There is an upper bound on this of course,
+and if the JIT hits that limit, the last two iterations are run with all
+branches being converted.
+
+Tail call count
+===============
+The current tail call count is stored in the 16-byte area of the caller's
+stack frame that is reserved for the callee in the o32 ABI. The value is
+initialized in the prologue, and propagated to the tail-callee by skipping
+the initialization instructions when emitting the tail call.
+
+Signed-off-by: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+---
+ create mode 100644 arch/mips/net/bpf_jit_comp.c
+ create mode 100644 arch/mips/net/bpf_jit_comp.h
+ create mode 100644 arch/mips/net/bpf_jit_comp32.c
+
+--- a/arch/mips/net/Makefile
++++ b/arch/mips/net/Makefile
+@@ -2,4 +2,9 @@
+ # MIPS networking code
+ 
+ obj-$(CONFIG_MIPS_CBPF_JIT) += bpf_jit.o bpf_jit_asm.o
+-obj-$(CONFIG_MIPS_EBPF_JIT) += ebpf_jit.o
++
++ifeq ($(CONFIG_32BIT),y)
++        obj-$(CONFIG_MIPS_EBPF_JIT) += bpf_jit_comp.o bpf_jit_comp32.o
++else
++        obj-$(CONFIG_MIPS_EBPF_JIT) += ebpf_jit.o
++endif
+--- /dev/null
++++ b/arch/mips/net/bpf_jit_comp.c
+@@ -0,0 +1,1020 @@
++// SPDX-License-Identifier: GPL-2.0-only
++/*
++ * Just-In-Time compiler for eBPF bytecode on MIPS.
++ * Implementation of JIT functions common to 32-bit and 64-bit CPUs.
++ *
++ * Copyright (c) 2021 Anyfi Networks AB.
++ * Author: Johan Almbladh <johan.almbladh at gmail.com>
++ *
++ * Based on code and ideas from
++ * Copyright (c) 2017 Cavium, Inc.
++ * Copyright (c) 2017 Shubham Bansal <illusionist.neo at gmail.com>
++ * Copyright (c) 2011 Mircea Gherzan <mgherzan at gmail.com>
++ */
++
++/*
++ * Code overview
++ * =============
++ *
++ * - bpf_jit_comp.h
++ *   Common definitions and utilities.
++ *
++ * - bpf_jit_comp.c
++ *   Implementation of JIT top-level logic and exported JIT API functions.
++ *   Implementation of internal operations shared by 32-bit and 64-bit code.
++ *   JMP and ALU JIT control code, register control code, shared ALU and
++ *   JMP/JMP32 JIT operations.
++ *
++ * - bpf_jit_comp32.c
++ *   Implementation of functions to JIT prologue, epilogue and a single eBPF
++ *   instruction for 32-bit MIPS CPUs. The functions use shared operations
++ *   where possible, and implement the rest for 32-bit MIPS such as ALU64
++ *   operations.
++ *
++ * - bpf_jit_comp64.c
++ *   Ditto, for 64-bit MIPS CPUs.
++ *
++ * Zero and sign extension
++ * ========================
++ * 32-bit MIPS instructions on 64-bit MIPS registers use sign extension,
++ * but the eBPF instruction set mandates zero extension. We let the verifier
++ * insert explicit zero-extensions after 32-bit ALU operations, both for
++ * 32-bit and 64-bit MIPS JITs. Conditional JMP32 operations on 64-bit MIPs
++ * are JITed with sign extensions inserted when so expected.
++ *
++ * ALU operations
++ * ==============
++ * ALU operations on 32/64-bit MIPS and ALU64 operations on 64-bit MIPS are
++ * JITed in the following steps. ALU64 operations on 32-bit MIPS are more
++ * complicated and therefore only processed by special implementations in
++ * step (3).
++ *
++ * 1) valid_alu_i:
++ *    Determine if an immediate operation can be emitted as such, or if
++ *    we must fall back to the register version.
++ *
++ * 2) rewrite_alu_i:
++ *    Convert BPF operation and immediate value to a canonical form for
++ *    JITing. In some degenerate cases this form may be a no-op.
++ *
++ * 3) emit_alu_{i,i64,r,64}:
++ *    Emit instructions for an ALU or ALU64 immediate or register operation.
++ *
++ * JMP operations
++ * ==============
++ * JMP and JMP32 operations require an JIT instruction offset table for
++ * translating the jump offset. This table is computed by dry-running the
++ * JIT without actually emitting anything. However, the computed PC-relative
++ * offset may overflow the 18-bit offset field width of the native MIPS
++ * branch instruction. In such cases, the long jump is converted into the
++ * following sequence.
++ *
++ *    <branch> !<cond> +2    Inverted PC-relative branch
++ *    nop                    Delay slot
++ *    j <offset>             Unconditional absolute long jump
++ *    nop                    Delay slot
++ *
++ * Since this converted sequence alters the offset table, all offsets must
++ * be re-calculated. This may in turn trigger new branch conversions, so
++ * the process is repeated until no further changes are made. Normally it
++ * completes in 1-2 iterations. If JIT_MAX_ITERATIONS should reached, we
++ * fall back to converting every remaining jump operation. The branch
++ * conversion is independent of how the JMP or JMP32 condition is JITed.
++ *
++ * JMP32 and JMP operations are JITed as follows.
++ *
++ * 1) setup_jmp_{i,r}:
++ *    Convert jump conditional and offset into a form that can be JITed.
++ *    This form may be a no-op, a canonical form, or an inverted PC-relative
++ *    jump if branch conversion is necessary.
++ *
++ * 2) valid_jmp_i:
++ *    Determine if an immediate operations can be emitted as such, or if
++ *    we must fall back to the register version. Applies to JMP32 for 32-bit
++ *    MIPS, and both JMP and JMP32 for 64-bit MIPS.
++ *
++ * 3) emit_jmp_{i,i64,r,r64}:
++ *    Emit instructions for an JMP or JMP32 immediate or register operation.
++ *
++ * 4) finish_jmp_{i,r}:
++ *    Emit any instructions needed to finish the jump. This includes a nop
++ *    for the delay slot if a branch was emitted, and a long absolute jump
++ *    if the branch was converted.
++ */
++
++#include <linux/limits.h>
++#include <linux/bitops.h>
++#include <linux/errno.h>
++#include <linux/filter.h>
++#include <linux/bpf.h>
++#include <linux/slab.h>
++#include <asm/bitops.h>
++#include <asm/cacheflush.h>
++#include <asm/cpu-features.h>
++#include <asm/isa-rev.h>
++#include <asm/uasm.h>
++
++#include "bpf_jit_comp.h"
++
++/* Convenience macros for descriptor access */
++#define CONVERTED(desc)	((desc) & JIT_DESC_CONVERT)
++#define INDEX(desc)	((desc) & ~JIT_DESC_CONVERT)
++
++/*
++ * Push registers on the stack, starting at a given depth from the stack
++ * pointer and increasing. The next depth to be written is returned.
++ */
++int push_regs(struct jit_context *ctx, u32 mask, u32 excl, int depth)
++{
++	int reg;
++
++	for (reg = 0; reg < BITS_PER_BYTE * sizeof(mask); reg++)
++		if (mask & BIT(reg)) {
++			if ((excl & BIT(reg)) == 0) {
++				if (sizeof(long) == 4)
++					emit(ctx, sw, reg, depth, MIPS_R_SP);
++				else /* sizeof(long) == 8 */
++					emit(ctx, sd, reg, depth, MIPS_R_SP);
++			}
++			depth += sizeof(long);
++		}
++
++	ctx->stack_used = max((int)ctx->stack_used, depth);
++	return depth;
++}
++
++/*
++ * Pop registers from the stack, starting at a given depth from the stack
++ * pointer and increasing. The next depth to be read is returned.
++ */
++int pop_regs(struct jit_context *ctx, u32 mask, u32 excl, int depth)
++{
++	int reg;
++
++	for (reg = 0; reg < BITS_PER_BYTE * sizeof(mask); reg++)
++		if (mask & BIT(reg)) {
++			if ((excl & BIT(reg)) == 0) {
++				if (sizeof(long) == 4)
++					emit(ctx, lw, reg, depth, MIPS_R_SP);
++				else /* sizeof(long) == 8 */
++					emit(ctx, ld, reg, depth, MIPS_R_SP);
++			}
++			depth += sizeof(long);
++		}
++
++	return depth;
++}
++
++/* Compute the 28-bit jump target address from a BPF program location */
++int get_target(struct jit_context *ctx, u32 loc)
++{
++	u32 index = INDEX(ctx->descriptors[loc]);
++	unsigned long pc = (unsigned long)&ctx->target[ctx->jit_index];
++	unsigned long addr = (unsigned long)&ctx->target[index];
++
++	if (!ctx->target)
++		return 0;
++
++	if ((addr ^ pc) & ~MIPS_JMP_MASK)
++		return -1;
++
++	return addr & MIPS_JMP_MASK;
++}
++
++/* Compute the PC-relative offset to relative BPF program offset */
++int get_offset(const struct jit_context *ctx, int off)
++{
++	return (INDEX(ctx->descriptors[ctx->bpf_index + off]) -
++		ctx->jit_index - 1) * sizeof(u32);
++}
++
++/* dst = imm (register width) */
++void emit_mov_i(struct jit_context *ctx, u8 dst, s32 imm)
++{
++	if (imm >= -0x8000 && imm <= 0x7fff) {
++		emit(ctx, addiu, dst, MIPS_R_ZERO, imm);
++	} else {
++		emit(ctx, lui, dst, (s16)((u32)imm >> 16));
++		emit(ctx, ori, dst, dst, (u16)(imm & 0xffff));
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* dst = src (register width) */
++void emit_mov_r(struct jit_context *ctx, u8 dst, u8 src)
++{
++	emit(ctx, ori, dst, src, 0);
++	clobber_reg(ctx, dst);
++}
++
++/* Validate ALU immediate range */
++bool valid_alu_i(u8 op, s32 imm)
++{
++	switch (BPF_OP(op)) {
++	case BPF_NEG:
++	case BPF_LSH:
++	case BPF_RSH:
++	case BPF_ARSH:
++		/* All legal eBPF values are valid */
++		return true;
++	case BPF_ADD:
++		/* imm must be 16 bits */
++		return imm >= -0x8000 && imm <= 0x7fff;
++	case BPF_SUB:
++		/* -imm must be 16 bits */
++		return imm >= -0x7fff && imm <= 0x8000;
++	case BPF_AND:
++	case BPF_OR:
++	case BPF_XOR:
++		/* imm must be 16 bits unsigned */
++		return imm >= 0 && imm <= 0xffff;
++	case BPF_MUL:
++		/* imm must be zero or a positive power of two */
++		return imm == 0 || (imm > 0 && is_power_of_2(imm));
++	case BPF_DIV:
++	case BPF_MOD:
++		/* imm must be an 17-bit power of two */
++		return (u32)imm <= 0x10000 && is_power_of_2((u32)imm);
++	}
++	return false;
++}
++
++/* Rewrite ALU immediate operation */
++bool rewrite_alu_i(u8 op, s32 imm, u8 *alu, s32 *val)
++{
++	bool act = true;
++
++	switch (BPF_OP(op)) {
++	case BPF_LSH:
++	case BPF_RSH:
++	case BPF_ARSH:
++	case BPF_ADD:
++	case BPF_SUB:
++	case BPF_OR:
++	case BPF_XOR:
++		/* imm == 0 is a no-op */
++		act = imm != 0;
++		break;
++	case BPF_MUL:
++		if (imm == 1) {
++			/* dst * 1 is a no-op */
++			act = false;
++		} else if (imm == 0) {
++			/* dst * 0 is dst & 0 */
++			op = BPF_AND;
++		} else {
++			/* dst * (1 << n) is dst << n */
++			op = BPF_LSH;
++			imm = ilog2(abs(imm));
++		}
++		break;
++	case BPF_DIV:
++		if (imm == 1) {
++			/* dst / 1 is a no-op */
++			act = false;
++		} else {
++			/* dst / (1 << n) is dst >> n */
++			op = BPF_RSH;
++			imm = ilog2(imm);
++		}
++		break;
++	case BPF_MOD:
++		/* dst % (1 << n) is dst & ((1 << n) - 1) */
++		op = BPF_AND;
++		imm--;
++		break;
++	}
++
++	*alu = op;
++	*val = imm;
++	return act;
++}
++
++/* ALU immediate operation (32-bit) */
++void emit_alu_i(struct jit_context *ctx, u8 dst, s32 imm, u8 op)
++{
++	switch (BPF_OP(op)) {
++	/* dst = -dst */
++	case BPF_NEG:
++		emit(ctx, subu, dst, MIPS_R_ZERO, dst);
++		break;
++	/* dst = dst & imm */
++	case BPF_AND:
++		emit(ctx, andi, dst, dst, (u16)imm);
++		break;
++	/* dst = dst | imm */
++	case BPF_OR:
++		emit(ctx, ori, dst, dst, (u16)imm);
++		break;
++	/* dst = dst ^ imm */
++	case BPF_XOR:
++		emit(ctx, xori, dst, dst, (u16)imm);
++		break;
++	/* dst = dst << imm */
++	case BPF_LSH:
++		emit(ctx, sll, dst, dst, imm);
++		break;
++	/* dst = dst >> imm */
++	case BPF_RSH:
++		emit(ctx, srl, dst, dst, imm);
++		break;
++	/* dst = dst >> imm (arithmetic) */
++	case BPF_ARSH:
++		emit(ctx, sra, dst, dst, imm);
++		break;
++	/* dst = dst + imm */
++	case BPF_ADD:
++		emit(ctx, addiu, dst, dst, imm);
++		break;
++	/* dst = dst - imm */
++	case BPF_SUB:
++		emit(ctx, addiu, dst, dst, -imm);
++		break;
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* ALU register operation (32-bit) */
++void emit_alu_r(struct jit_context *ctx, u8 dst, u8 src, u8 op)
++{
++	switch (BPF_OP(op)) {
++	/* dst = dst & src */
++	case BPF_AND:
++		emit(ctx, and, dst, dst, src);
++		break;
++	/* dst = dst | src */
++	case BPF_OR:
++		emit(ctx, or, dst, dst, src);
++		break;
++	/* dst = dst ^ src */
++	case BPF_XOR:
++		emit(ctx, xor, dst, dst, src);
++		break;
++	/* dst = dst << src */
++	case BPF_LSH:
++		emit(ctx, sllv, dst, dst, src);
++		break;
++	/* dst = dst >> src */
++	case BPF_RSH:
++		emit(ctx, srlv, dst, dst, src);
++		break;
++	/* dst = dst >> src (arithmetic) */
++	case BPF_ARSH:
++		emit(ctx, srav, dst, dst, src);
++		break;
++	/* dst = dst + src */
++	case BPF_ADD:
++		emit(ctx, addu, dst, dst, src);
++		break;
++	/* dst = dst - src */
++	case BPF_SUB:
++		emit(ctx, subu, dst, dst, src);
++		break;
++	/* dst = dst * src */
++	case BPF_MUL:
++		if (cpu_has_mips32r1 || cpu_has_mips32r6) {
++			emit(ctx, mul, dst, dst, src);
++		} else {
++			emit(ctx, multu, dst, src);
++			emit(ctx, mflo, dst);
++		}
++		break;
++	/* dst = dst / src */
++	case BPF_DIV:
++		if (cpu_has_mips32r6) {
++			emit(ctx, divu_r6, dst, dst, src);
++		} else {
++			emit(ctx, divu, dst, src);
++			emit(ctx, mflo, dst);
++		}
++		break;
++	/* dst = dst % src */
++	case BPF_MOD:
++		if (cpu_has_mips32r6) {
++			emit(ctx, modu, dst, dst, src);
++		} else {
++			emit(ctx, divu, dst, src);
++			emit(ctx, mfhi, dst);
++		}
++		break;
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* Atomic read-modify-write (32-bit) */
++void emit_atomic_r(struct jit_context *ctx, u8 dst, u8 src, s16 off, u8 code)
++{
++	emit(ctx, ll, MIPS_R_T9, off, dst);
++	switch (code) {
++	case BPF_ADD:
++		emit(ctx, addu, MIPS_R_T8, MIPS_R_T9, src);
++		break;
++	case BPF_AND:
++		emit(ctx, and, MIPS_R_T8, MIPS_R_T9, src);
++		break;
++	case BPF_OR:
++		emit(ctx, or, MIPS_R_T8, MIPS_R_T9, src);
++		break;
++	case BPF_XOR:
++		emit(ctx, xor, MIPS_R_T8, MIPS_R_T9, src);
++		break;
++	}
++	emit(ctx, sc, MIPS_R_T8, off, dst);
++	emit(ctx, beqz, MIPS_R_T8, -16);
++	emit(ctx, nop); /* Delay slot */
++}
++
++/* Atomic compare-and-exchange (32-bit) */
++void emit_cmpxchg_r(struct jit_context *ctx, u8 dst, u8 src, u8 res, s16 off)
++{
++	emit(ctx, ll, MIPS_R_T9, off, dst);
++	emit(ctx, bne, MIPS_R_T9, res, 12);
++	emit(ctx, move, MIPS_R_T8, src);     /* Delay slot */
++	emit(ctx, sc, MIPS_R_T8, off, dst);
++	emit(ctx, beqz, MIPS_R_T8, -20);
++	emit(ctx, move, res, MIPS_R_T9);     /* Delay slot */
++	clobber_reg(ctx, res);
++}
++
++/* Swap bytes and truncate a register word or half word */
++void emit_bswap_r(struct jit_context *ctx, u8 dst, u32 width)
++{
++	u8 tmp = MIPS_R_T8;
++	u8 msk = MIPS_R_T9;
++
++	switch (width) {
++	/* Swap bytes in a word */
++	case 32:
++		if (cpu_has_mips32r2 || cpu_has_mips32r6) {
++			emit(ctx, wsbh, dst, dst);
++			emit(ctx, rotr, dst, dst, 16);
++		} else {
++			emit(ctx, sll, tmp, dst, 16);    /* tmp  = dst << 16 */
++			emit(ctx, srl, dst, dst, 16);    /* dst = dst >> 16  */
++			emit(ctx, or, dst, dst, tmp);    /* dst = dst | tmp  */
++
++			emit(ctx, lui, msk, 0xff);       /* msk = 0x00ff0000 */
++			emit(ctx, ori, msk, msk, 0xff);  /* msk = msk | 0xff */
++
++			emit(ctx, and, tmp, dst, msk);   /* tmp = dst & msk  */
++			emit(ctx, sll, tmp, tmp, 8);     /* tmp = tmp << 8   */
++			emit(ctx, srl, dst, dst, 8);     /* dst = dst >> 8   */
++			emit(ctx, and, dst, dst, msk);   /* dst = dst & msk  */
++			emit(ctx, or, dst, dst, tmp);    /* reg = dst | tmp  */
++		}
++		break;
++	/* Swap bytes in a half word */
++	case 16:
++		if (cpu_has_mips32r2 || cpu_has_mips32r6) {
++			emit(ctx, wsbh, dst, dst);
++			emit(ctx, andi, dst, dst, 0xffff);
++		} else {
++			emit(ctx, andi, tmp, dst, 0xff00); /* t = d & 0xff00 */
++			emit(ctx, srl, tmp, tmp, 8);       /* t = t >> 8     */
++			emit(ctx, andi, dst, dst, 0x00ff); /* d = d & 0x00ff */
++			emit(ctx, sll, dst, dst, 8);       /* d = d << 8     */
++			emit(ctx, or,  dst, dst, tmp);     /* d = d | t      */
++		}
++		break;
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* Validate jump immediate range */
++bool valid_jmp_i(u8 op, s32 imm)
++{
++	switch (op) {
++	case JIT_JNOP:
++		/* Immediate value not used */
++		return true;
++	case BPF_JEQ:
++	case BPF_JNE:
++		/* No immediate operation */
++		return false;
++	case BPF_JSET:
++	case JIT_JNSET:
++		/* imm must be 16 bits unsigned */
++		return imm >= 0 && imm <= 0xffff;
++	case BPF_JGE:
++	case BPF_JLT:
++	case BPF_JSGE:
++	case BPF_JSLT:
++		/* imm must be 16 bits */
++		return imm >= -0x8000 && imm <= 0x7fff;
++	case BPF_JGT:
++	case BPF_JLE:
++	case BPF_JSGT:
++	case BPF_JSLE:
++		/* imm + 1 must be 16 bits */
++		return imm >= -0x8001 && imm <= 0x7ffe;
++	}
++	return false;
++}
++
++/* Invert a conditional jump operation */
++static u8 invert_jmp(u8 op)
++{
++	switch (op) {
++	case BPF_JA: return JIT_JNOP;
++	case BPF_JEQ: return BPF_JNE;
++	case BPF_JNE: return BPF_JEQ;
++	case BPF_JSET: return JIT_JNSET;
++	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 0;
++}
++
++/* Prepare a PC-relative jump operation */
++static void setup_jmp(struct jit_context *ctx, u8 bpf_op,
++		      s16 bpf_off, u8 *jit_op, s32 *jit_off)
++{
++	u32 *descp = &ctx->descriptors[ctx->bpf_index];
++	int op = bpf_op;
++	int offset = 0;
++
++	/* Do not compute offsets on the first pass */
++	if (INDEX(*descp) == 0)
++		goto done;
++
++	/* Skip jumps never taken */
++	if (bpf_op == JIT_JNOP)
++		goto done;
++
++	/* Convert jumps always taken */
++	if (bpf_op == BPF_JA)
++		*descp |= JIT_DESC_CONVERT;
++
++	/*
++	 * Current ctx->jit_index points to the start of the branch preamble.
++	 * Since the preamble differs among different branch conditionals,
++	 * the current index cannot be used to compute the branch offset.
++	 * Instead, we use the offset table value for the next instruction,
++	 * which gives the index immediately after the branch delay slot.
++	 */
++	if (!CONVERTED(*descp)) {
++		int target = ctx->bpf_index + bpf_off + 1;
++		int origin = ctx->bpf_index + 1;
++
++		offset = (INDEX(ctx->descriptors[target]) -
++			  INDEX(ctx->descriptors[origin]) + 1) * sizeof(u32);
++	}
++
++	/*
++	 * The PC-relative branch offset field on MIPS is 18 bits signed,
++	 * so if the computed offset is larger than this we generate a an
++	 * absolute jump that we skip with an inverted conditional branch.
++	 */
++	if (CONVERTED(*descp) || offset < -0x20000 || offset > 0x1ffff) {
++		offset = 3 * sizeof(u32);
++		op = invert_jmp(bpf_op);
++		ctx->changes += !CONVERTED(*descp);
++		*descp |= JIT_DESC_CONVERT;
++	}
++
++done:
++	*jit_off = offset;
++	*jit_op = op;
++}
++
++/* Prepare a PC-relative jump operation with immediate conditional */
++void setup_jmp_i(struct jit_context *ctx, s32 imm, u8 width,
++		 u8 bpf_op, s16 bpf_off, u8 *jit_op, s32 *jit_off)
++{
++	bool always = false;
++	bool never = false;
++
++	switch (bpf_op) {
++	case BPF_JEQ:
++	case BPF_JNE:
++		break;
++	case BPF_JSET:
++	case BPF_JLT:
++		never = imm == 0;
++		break;
++	case BPF_JGE:
++		always = imm == 0;
++		break;
++	case BPF_JGT:
++		never = (u32)imm == U32_MAX;
++		break;
++	case BPF_JLE:
++		always = (u32)imm == U32_MAX;
++		break;
++	case BPF_JSGT:
++		never = imm == S32_MAX && width == 32;
++		break;
++	case BPF_JSGE:
++		always = imm == S32_MIN && width == 32;
++		break;
++	case BPF_JSLT:
++		never = imm == S32_MIN && width == 32;
++		break;
++	case BPF_JSLE:
++		always = imm == S32_MAX && width == 32;
++		break;
++	}
++
++	if (never)
++		bpf_op = JIT_JNOP;
++	if (always)
++		bpf_op = BPF_JA;
++	setup_jmp(ctx, bpf_op, bpf_off, jit_op, jit_off);
++}
++
++/* Prepare a PC-relative jump operation with register conditional */
++void setup_jmp_r(struct jit_context *ctx, bool same_reg,
++		 u8 bpf_op, s16 bpf_off, u8 *jit_op, s32 *jit_off)
++{
++	switch (bpf_op) {
++	case BPF_JSET:
++		break;
++	case BPF_JEQ:
++	case BPF_JGE:
++	case BPF_JLE:
++	case BPF_JSGE:
++	case BPF_JSLE:
++		if (same_reg)
++			bpf_op = BPF_JA;
++		break;
++	case BPF_JNE:
++	case BPF_JLT:
++	case BPF_JGT:
++	case BPF_JSGT:
++	case BPF_JSLT:
++		if (same_reg)
++			bpf_op = JIT_JNOP;
++		break;
++	}
++	setup_jmp(ctx, bpf_op, bpf_off, jit_op, jit_off);
++}
++
++/* Finish a PC-relative jump operation */
++int finish_jmp(struct jit_context *ctx, u8 jit_op, s16 bpf_off)
++{
++	/* Emit conditional branch delay slot */
++	if (jit_op != JIT_JNOP)
++		emit(ctx, nop);
++	/*
++	 * Emit an absolute long jump with delay slot,
++	 * if the PC-relative branch was converted.
++	 */
++	if (CONVERTED(ctx->descriptors[ctx->bpf_index])) {
++		int target = get_target(ctx, ctx->bpf_index + bpf_off + 1);
++
++		if (target < 0)
++			return -1;
++		emit(ctx, j, target);
++		emit(ctx, nop);
++	}
++	return 0;
++}
++
++/* Jump immediate (32-bit) */
++void emit_jmp_i(struct jit_context *ctx, u8 dst, s32 imm, s32 off, u8 op)
++{
++	switch (op) {
++	/* No-op, used internally for branch optimization */
++	case JIT_JNOP:
++		break;
++	/* PC += off if dst & imm */
++	case BPF_JSET:
++		emit(ctx, andi, MIPS_R_T9, dst, (u16)imm);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	/* PC += off if (dst & imm) == 0 (not in BPF, used for long jumps) */
++	case JIT_JNSET:
++		emit(ctx, andi, MIPS_R_T9, dst, (u16)imm);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst > imm */
++	case BPF_JGT:
++		emit(ctx, sltiu, MIPS_R_T9, dst, imm + 1);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst >= imm */
++	case BPF_JGE:
++		emit(ctx, sltiu, MIPS_R_T9, dst, imm);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst < imm */
++	case BPF_JLT:
++		emit(ctx, sltiu, MIPS_R_T9, dst, imm);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst <= imm */
++	case BPF_JLE:
++		emit(ctx, sltiu, MIPS_R_T9, dst, imm + 1);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst > imm (signed) */
++	case BPF_JSGT:
++		emit(ctx, slti, MIPS_R_T9, dst, imm + 1);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst >= imm (signed) */
++	case BPF_JSGE:
++		emit(ctx, slti, MIPS_R_T9, dst, imm);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst < imm (signed) */
++	case BPF_JSLT:
++		emit(ctx, slti, MIPS_R_T9, dst, imm);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst <= imm (signed) */
++	case BPF_JSLE:
++		emit(ctx, slti, MIPS_R_T9, dst, imm + 1);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	}
++}
++
++/* Jump register (32-bit) */
++void emit_jmp_r(struct jit_context *ctx, u8 dst, u8 src, s32 off, u8 op)
++{
++	switch (op) {
++	/* No-op, used internally for branch optimization */
++	case JIT_JNOP:
++		break;
++	/* PC += off if dst == src */
++	case BPF_JEQ:
++		emit(ctx, beq, dst, src, off);
++		break;
++	/* PC += off if dst != src */
++	case BPF_JNE:
++		emit(ctx, bne, dst, src, off);
++		break;
++	/* PC += off if dst & src */
++	case BPF_JSET:
++		emit(ctx, and, MIPS_R_T9, dst, src);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	/* PC += off if (dst & imm) == 0 (not in BPF, used for long jumps) */
++	case JIT_JNSET:
++		emit(ctx, and, MIPS_R_T9, dst, src);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst > src */
++	case BPF_JGT:
++		emit(ctx, sltu, MIPS_R_T9, src, dst);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst >= src */
++	case BPF_JGE:
++		emit(ctx, sltu, MIPS_R_T9, dst, src);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst < src */
++	case BPF_JLT:
++		emit(ctx, sltu, MIPS_R_T9, dst, src);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst <= src */
++	case BPF_JLE:
++		emit(ctx, sltu, MIPS_R_T9, src, dst);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst > src (signed) */
++	case BPF_JSGT:
++		emit(ctx, slt, MIPS_R_T9, src, dst);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst >= src (signed) */
++	case BPF_JSGE:
++		emit(ctx, slt, MIPS_R_T9, dst, src);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst < src (signed) */
++	case BPF_JSLT:
++		emit(ctx, slt, MIPS_R_T9, dst, src);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst <= src (signed) */
++	case BPF_JSLE:
++		emit(ctx, slt, MIPS_R_T9, src, dst);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	}
++}
++
++/* Jump always */
++int emit_ja(struct jit_context *ctx, s16 off)
++{
++	int target = get_target(ctx, ctx->bpf_index + off + 1);
++
++	if (target < 0)
++		return -1;
++	emit(ctx, j, target);
++	emit(ctx, nop);
++	return 0;
++}
++
++/* Jump to epilogue */
++int emit_exit(struct jit_context *ctx)
++{
++	int target = get_target(ctx, ctx->program->len);
++
++	if (target < 0)
++		return -1;
++	emit(ctx, j, target);
++	emit(ctx, nop);
++	return 0;
++}
++
++/* Build the program body from eBPF bytecode */
++static int build_body(struct jit_context *ctx)
++{
++	const struct bpf_prog *prog = ctx->program;
++	unsigned int i;
++
++	ctx->stack_used = 0;
++	for (i = 0; i < prog->len; i++) {
++		const struct bpf_insn *insn = &prog->insnsi[i];
++		u32 *descp = &ctx->descriptors[i];
++		int ret;
++
++		access_reg(ctx, insn->src_reg);
++		access_reg(ctx, insn->dst_reg);
++
++		ctx->bpf_index = i;
++		if (ctx->target == NULL) {
++			ctx->changes += INDEX(*descp) != ctx->jit_index;
++			*descp &= JIT_DESC_CONVERT;
++			*descp |= ctx->jit_index;
++		}
++
++		ret = build_insn(insn, ctx);
++		if (ret < 0)
++			return ret;
++
++		if (ret > 0) {
++			i++;
++			if (ctx->target == NULL)
++				descp[1] = ctx->jit_index;
++		}
++	}
++
++	/* Store the end offset, where the epilogue begins */
++	ctx->descriptors[prog->len] = ctx->jit_index;
++	return 0;
++}
++
++/* Set the branch conversion flag on all instructions */
++static void set_convert_flag(struct jit_context *ctx, bool enable)
++{
++	const struct bpf_prog *prog = ctx->program;
++	u32 flag = enable ? JIT_DESC_CONVERT : 0;
++	unsigned int i;
++
++	for (i = 0; i <= prog->len; i++)
++		ctx->descriptors[i] = INDEX(ctx->descriptors[i]) | flag;
++}
++
++static void jit_fill_hole(void *area, unsigned int size)
++{
++	u32 *p;
++
++	/* We are guaranteed to have aligned memory. */
++	for (p = area; size >= sizeof(u32); size -= sizeof(u32))
++		uasm_i_break(&p, BRK_BUG); /* Increments p */
++}
++
++bool bpf_jit_needs_zext(void)
++{
++	return true;
++}
++
++struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
++{
++	struct bpf_prog *tmp, *orig_prog = prog;
++	struct bpf_binary_header *header = NULL;
++	struct jit_context ctx;
++	bool tmp_blinded = false;
++	unsigned int tmp_idx;
++	unsigned int image_size;
++	u8 *image_ptr;
++	int tries;
++
++	/*
++	 * If BPF JIT was not enabled then we must fall back to
++	 * the interpreter.
++	 */
++	if (!prog->jit_requested)
++		return orig_prog;
++	/*
++	 * If constant blinding was enabled and we failed during blinding
++	 * then we must fall back to the interpreter. Otherwise, we save
++	 * the new JITed code.
++	 */
++	tmp = bpf_jit_blind_constants(prog);
++	if (IS_ERR(tmp))
++		return orig_prog;
++	if (tmp != prog) {
++		tmp_blinded = true;
++		prog = tmp;
++	}
++
++	memset(&ctx, 0, sizeof(ctx));
++	ctx.program = prog;
++
++	/*
++	 * Not able to allocate memory for descriptors[], then
++	 * we must fall back to the interpreter
++	 */
++	ctx.descriptors = kcalloc(prog->len + 1, sizeof(*ctx.descriptors),
++				  GFP_KERNEL);
++	if (ctx.descriptors == NULL)
++		goto out_err;
++
++	/* First pass discovers used resources */
++	if (build_body(&ctx) < 0)
++		goto out_err;
++	/*
++	 * Second pass computes instruction offsets.
++	 * If any PC-relative branches are out of range, a sequence of
++	 * a PC-relative branch + a jump is generated, and we have to
++	 * try again from the beginning to generate the new offsets.
++	 * This is done until no additional conversions are necessary.
++	 * The last two iterations are done with all branches being
++	 * converted, to guarantee offset table convergence within a
++	 * fixed number of iterations.
++	 */
++	ctx.jit_index = 0;
++	build_prologue(&ctx);
++	tmp_idx = ctx.jit_index;
++
++	tries = JIT_MAX_ITERATIONS;
++	do {
++		ctx.jit_index = tmp_idx;
++		ctx.changes = 0;
++		if (tries == 2)
++			set_convert_flag(&ctx, true);
++		if (build_body(&ctx) < 0)
++			goto out_err;
++	} while (ctx.changes > 0 && --tries > 0);
++
++	if (WARN_ONCE(ctx.changes > 0, "JIT offsets failed to converge"))
++		goto out_err;
++
++	build_epilogue(&ctx, MIPS_R_RA);
++
++	/* Now we know the size of the structure to make */
++	image_size = sizeof(u32) * ctx.jit_index;
++	header = bpf_jit_binary_alloc(image_size, &image_ptr,
++				      sizeof(u32), jit_fill_hole);
++	/*
++	 * Not able to allocate memory for the structure then
++	 * we must fall back to the interpretation
++	 */
++	if (header == NULL)
++		goto out_err;
++
++	/* Actual pass to generate final JIT code */
++	ctx.target = (u32 *)image_ptr;
++	ctx.jit_index = 0;
++
++	/*
++	 * If building the JITed code fails somehow,
++	 * we fall back to the interpretation.
++	 */
++	build_prologue(&ctx);
++	if (build_body(&ctx) < 0)
++		goto out_err;
++	build_epilogue(&ctx, MIPS_R_RA);
++
++	/* Populate line info meta data */
++	set_convert_flag(&ctx, false);
++	bpf_prog_fill_jited_linfo(prog, &ctx.descriptors[1]);
++
++	/* Set as read-only exec and flush instruction cache */
++	bpf_jit_binary_lock_ro(header);
++	flush_icache_range((unsigned long)header,
++			   (unsigned long)&ctx.target[ctx.jit_index]);
++
++	if (bpf_jit_enable > 1)
++		bpf_jit_dump(prog->len, image_size, 2, ctx.target);
++
++	prog->bpf_func = (void *)ctx.target;
++	prog->jited = 1;
++	prog->jited_len = image_size;
++
++out:
++	if (tmp_blinded)
++		bpf_jit_prog_release_other(prog, prog == orig_prog ?
++					   tmp : orig_prog);
++	kfree(ctx.descriptors);
++	return prog;
++
++out_err:
++	prog = orig_prog;
++	if (header)
++		bpf_jit_binary_free(header);
++	goto out;
++}
+--- /dev/null
++++ b/arch/mips/net/bpf_jit_comp.h
+@@ -0,0 +1,211 @@
++/* SPDX-License-Identifier: GPL-2.0-only */
++/*
++ * Just-In-Time compiler for eBPF bytecode on 32-bit and 64-bit MIPS.
++ *
++ * Copyright (c) 2021 Anyfi Networks AB.
++ * Author: Johan Almbladh <johan.almbladh at gmail.com>
++ *
++ * Based on code and ideas from
++ * Copyright (c) 2017 Cavium, Inc.
++ * Copyright (c) 2017 Shubham Bansal <illusionist.neo at gmail.com>
++ * Copyright (c) 2011 Mircea Gherzan <mgherzan at gmail.com>
++ */
++
++#ifndef _BPF_JIT_COMP_H
++#define _BPF_JIT_COMP_H
++
++/* MIPS registers */
++#define MIPS_R_ZERO	0   /* Const zero */
++#define MIPS_R_AT	1   /* Asm temp   */
++#define MIPS_R_V0	2   /* Result     */
++#define MIPS_R_V1	3   /* Result     */
++#define MIPS_R_A0	4   /* Argument   */
++#define MIPS_R_A1	5   /* Argument   */
++#define MIPS_R_A2	6   /* Argument   */
++#define MIPS_R_A3	7   /* Argument   */
++#define MIPS_R_A4	8   /* Arg (n64)  */
++#define MIPS_R_A5	9   /* Arg (n64)  */
++#define MIPS_R_A6	10  /* Arg (n64)  */
++#define MIPS_R_A7	11  /* Arg (n64)  */
++#define MIPS_R_T0	8   /* Temp (o32) */
++#define MIPS_R_T1	9   /* Temp (o32) */
++#define MIPS_R_T2	10  /* Temp (o32) */
++#define MIPS_R_T3	11  /* Temp (o32) */
++#define MIPS_R_T4	12  /* Temporary  */
++#define MIPS_R_T5	13  /* Temporary  */
++#define MIPS_R_T6	14  /* Temporary  */
++#define MIPS_R_T7	15  /* Temporary  */
++#define MIPS_R_S0	16  /* Saved      */
++#define MIPS_R_S1	17  /* Saved      */
++#define MIPS_R_S2	18  /* Saved      */
++#define MIPS_R_S3	19  /* Saved      */
++#define MIPS_R_S4	20  /* Saved      */
++#define MIPS_R_S5	21  /* Saved      */
++#define MIPS_R_S6	22  /* Saved      */
++#define MIPS_R_S7	23  /* Saved      */
++#define MIPS_R_T8	24  /* Temporary  */
++#define MIPS_R_T9	25  /* Temporary  */
++/*      MIPS_R_K0	26     Reserved   */
++/*      MIPS_R_K1	27     Reserved   */
++#define MIPS_R_GP	28  /* Global ptr */
++#define MIPS_R_SP	29  /* Stack ptr  */
++#define MIPS_R_FP	30  /* Frame ptr  */
++#define MIPS_R_RA	31  /* Return     */
++
++/*
++ * Jump address mask for immediate jumps. The four most significant bits
++ * must be equal to PC.
++ */
++#define MIPS_JMP_MASK	0x0fffffffUL
++
++/* Maximum number of iterations in offset table computation */
++#define JIT_MAX_ITERATIONS	8
++
++/*
++ * Jump pseudo-instructions used internally
++ * for branch conversion and branch optimization.
++ */
++#define JIT_JNSET	0xe0
++#define JIT_JNOP	0xf0
++
++/* Descriptor flag for PC-relative branch conversion */
++#define JIT_DESC_CONVERT	BIT(31)
++
++/* JIT context for an eBPF program */
++struct jit_context {
++	struct bpf_prog *program;     /* The eBPF program being JITed        */
++	u32 *descriptors;             /* eBPF to JITed CPU insn descriptors  */
++	u32 *target;                  /* JITed code buffer                   */
++	u32 bpf_index;                /* Index of current BPF program insn   */
++	u32 jit_index;                /* Index of current JIT target insn    */
++	u32 changes;                  /* Number of PC-relative branch conv   */
++	u32 accessed;                 /* Bit mask of read eBPF registers     */
++	u32 clobbered;                /* Bit mask of modified CPU registers  */
++	u32 stack_size;               /* Total allocated stack size in bytes */
++	u32 saved_size;               /* Size of callee-saved registers      */
++	u32 stack_used;               /* Stack size used for function calls  */
++};
++
++/* Emit the instruction if the JIT memory space has been allocated */
++#define emit(ctx, func, ...)					\
++do {								\
++	if ((ctx)->target != NULL) {				\
++		u32 *p = &(ctx)->target[ctx->jit_index];	\
++		uasm_i_##func(&p, ##__VA_ARGS__);		\
++	}							\
++	(ctx)->jit_index++;					\
++} while (0)
++
++/*
++ * Mark a BPF register as accessed, it needs to be
++ * initialized by the program if expected, e.g. FP.
++ */
++static inline void access_reg(struct jit_context *ctx, u8 reg)
++{
++	ctx->accessed |= BIT(reg);
++}
++
++/*
++ * Mark a CPU register as clobbered, it needs to be
++ * saved/restored by the program if callee-saved.
++ */
++static inline void clobber_reg(struct jit_context *ctx, u8 reg)
++{
++	ctx->clobbered |= BIT(reg);
++}
++
++/*
++ * Push registers on the stack, starting at a given depth from the stack
++ * pointer and increasing. The next depth to be written is returned.
++ */
++int push_regs(struct jit_context *ctx, u32 mask, u32 excl, int depth);
++
++/*
++ * Pop registers from the stack, starting at a given depth from the stack
++ * pointer and increasing. The next depth to be read is returned.
++ */
++int pop_regs(struct jit_context *ctx, u32 mask, u32 excl, int depth);
++
++/* Compute the 28-bit jump target address from a BPF program location */
++int get_target(struct jit_context *ctx, u32 loc);
++
++/* Compute the PC-relative offset to relative BPF program offset */
++int get_offset(const struct jit_context *ctx, int off);
++
++/* dst = imm (32-bit) */
++void emit_mov_i(struct jit_context *ctx, u8 dst, s32 imm);
++
++/* dst = src (32-bit) */
++void emit_mov_r(struct jit_context *ctx, u8 dst, u8 src);
++
++/* Validate ALU/ALU64 immediate range */
++bool valid_alu_i(u8 op, s32 imm);
++
++/* Rewrite ALU/ALU64 immediate operation */
++bool rewrite_alu_i(u8 op, s32 imm, u8 *alu, s32 *val);
++
++/* ALU immediate operation (32-bit) */
++void emit_alu_i(struct jit_context *ctx, u8 dst, s32 imm, u8 op);
++
++/* ALU register operation (32-bit) */
++void emit_alu_r(struct jit_context *ctx, u8 dst, u8 src, u8 op);
++
++/* Atomic read-modify-write (32-bit) */
++void emit_atomic_r(struct jit_context *ctx, u8 dst, u8 src, s16 off, u8 code);
++
++/* Atomic compare-and-exchange (32-bit) */
++void emit_cmpxchg_r(struct jit_context *ctx, u8 dst, u8 src, u8 res, s16 off);
++
++/* Swap bytes and truncate a register word or half word */
++void emit_bswap_r(struct jit_context *ctx, u8 dst, u32 width);
++
++/* Validate JMP/JMP32 immediate range */
++bool valid_jmp_i(u8 op, s32 imm);
++
++/* Prepare a PC-relative jump operation with immediate conditional */
++void setup_jmp_i(struct jit_context *ctx, s32 imm, u8 width,
++		 u8 bpf_op, s16 bpf_off, u8 *jit_op, s32 *jit_off);
++
++/* Prepare a PC-relative jump operation with register conditional */
++void setup_jmp_r(struct jit_context *ctx, bool same_reg,
++		 u8 bpf_op, s16 bpf_off, u8 *jit_op, s32 *jit_off);
++
++/* Finish a PC-relative jump operation */
++int finish_jmp(struct jit_context *ctx, u8 jit_op, s16 bpf_off);
++
++/* Conditional JMP/JMP32 immediate */
++void emit_jmp_i(struct jit_context *ctx, u8 dst, s32 imm, s32 off, u8 op);
++
++/* Conditional JMP/JMP32 register */
++void emit_jmp_r(struct jit_context *ctx, u8 dst, u8 src, s32 off, u8 op);
++
++/* Jump always */
++int emit_ja(struct jit_context *ctx, s16 off);
++
++/* Jump to epilogue */
++int emit_exit(struct jit_context *ctx);
++
++/*
++ * Build program prologue to set up the stack and registers.
++ * This function is implemented separately for 32-bit and 64-bit JITs.
++ */
++void build_prologue(struct jit_context *ctx);
++
++/*
++ * Build the program epilogue to restore the stack and registers.
++ * This function is implemented separately for 32-bit and 64-bit JITs.
++ */
++void build_epilogue(struct jit_context *ctx, int dest_reg);
++
++/*
++ * Convert an eBPF instruction to native instruction, i.e
++ * JITs an eBPF instruction.
++ * Returns :
++ *	0  - Successfully JITed an 8-byte eBPF instruction
++ *	>0 - Successfully JITed a 16-byte eBPF instruction
++ *	<0 - Failed to JIT.
++ * This function is implemented separately for 32-bit and 64-bit JITs.
++ */
++int build_insn(const struct bpf_insn *insn, struct jit_context *ctx);
++
++#endif /* _BPF_JIT_COMP_H */
+--- /dev/null
++++ b/arch/mips/net/bpf_jit_comp32.c
+@@ -0,0 +1,1741 @@
++// SPDX-License-Identifier: GPL-2.0-only
++/*
++ * Just-In-Time compiler for eBPF bytecode on MIPS.
++ * Implementation of JIT functions for 32-bit CPUs.
++ *
++ * Copyright (c) 2021 Anyfi Networks AB.
++ * Author: Johan Almbladh <johan.almbladh at gmail.com>
++ *
++ * Based on code and ideas from
++ * Copyright (c) 2017 Cavium, Inc.
++ * Copyright (c) 2017 Shubham Bansal <illusionist.neo at gmail.com>
++ * Copyright (c) 2011 Mircea Gherzan <mgherzan at gmail.com>
++ */
++
++#include <linux/math64.h>
++#include <linux/errno.h>
++#include <linux/filter.h>
++#include <linux/bpf.h>
++#include <asm/cpu-features.h>
++#include <asm/isa-rev.h>
++#include <asm/uasm.h>
++
++#include "bpf_jit_comp.h"
++
++/* MIPS a4-a7 are not available in the o32 ABI */
++#undef MIPS_R_A4
++#undef MIPS_R_A5
++#undef MIPS_R_A6
++#undef MIPS_R_A7
++
++/* Stack is 8-byte aligned in o32 ABI */
++#define MIPS_STACK_ALIGNMENT 8
++
++/*
++ * The top 16 bytes of a stack frame is reserved for the callee in O32 ABI.
++ * This corresponds to stack space for register arguments a0-a3.
++ */
++#define JIT_RESERVED_STACK 16
++
++/* Temporary 64-bit register used by JIT */
++#define JIT_REG_TMP MAX_BPF_JIT_REG
++
++/*
++ * Number of prologue bytes to skip when doing a tail call.
++ * Tail call count (TCC) initialization (8 bytes) always, plus
++ * R0-to-v0 assignment (4 bytes) if big endian.
++ */
++#ifdef __BIG_ENDIAN
++#define JIT_TCALL_SKIP 12
++#else
++#define JIT_TCALL_SKIP 8
++#endif
++
++/* CPU registers holding the callee return value */
++#define JIT_RETURN_REGS	  \
++	(BIT(MIPS_R_V0) | \
++	 BIT(MIPS_R_V1))
++
++/* CPU registers arguments passed to callee directly */
++#define JIT_ARG_REGS      \
++	(BIT(MIPS_R_A0) | \
++	 BIT(MIPS_R_A1) | \
++	 BIT(MIPS_R_A2) | \
++	 BIT(MIPS_R_A3))
++
++/* CPU register arguments passed to callee on stack */
++#define JIT_STACK_REGS    \
++	(BIT(MIPS_R_T0) | \
++	 BIT(MIPS_R_T1) | \
++	 BIT(MIPS_R_T2) | \
++	 BIT(MIPS_R_T3) | \
++	 BIT(MIPS_R_T4) | \
++	 BIT(MIPS_R_T5))
++
++/* Caller-saved CPU registers */
++#define JIT_CALLER_REGS    \
++	(JIT_RETURN_REGS | \
++	 JIT_ARG_REGS    | \
++	 JIT_STACK_REGS)
++
++/* Callee-saved CPU registers */
++#define JIT_CALLEE_REGS   \
++	(BIT(MIPS_R_S0) | \
++	 BIT(MIPS_R_S1) | \
++	 BIT(MIPS_R_S2) | \
++	 BIT(MIPS_R_S3) | \
++	 BIT(MIPS_R_S4) | \
++	 BIT(MIPS_R_S5) | \
++	 BIT(MIPS_R_S6) | \
++	 BIT(MIPS_R_S7) | \
++	 BIT(MIPS_R_GP) | \
++	 BIT(MIPS_R_FP) | \
++	 BIT(MIPS_R_RA))
++
++/*
++ * Mapping of 64-bit eBPF registers to 32-bit native MIPS registers.
++ *
++ * 1) Native register pairs are ordered according to CPU endiannes, following
++ *    the MIPS convention for passing 64-bit arguments and return values.
++ * 2) The eBPF return value, arguments and callee-saved registers are mapped
++ *    to their native MIPS equivalents.
++ * 3) Since the 32 highest bits in the eBPF FP register are always zero,
++ *    only one general-purpose register is actually needed for the mapping.
++ *    We use the fp register for this purpose, and map the highest bits to
++ *    the MIPS register r0 (zero).
++ * 4) We use the MIPS gp and at registers as internal temporary registers
++ *    for constant blinding. The gp register is callee-saved.
++ * 5) One 64-bit temporary register is mapped for use when sign-extending
++ *    immediate operands. MIPS registers t6-t9 are available to the JIT
++ *    for as temporaries when implementing complex 64-bit operations.
++ *
++ * With this scheme all eBPF registers are being mapped to native MIPS
++ * registers without having to use any stack scratch space. The direct
++ * register mapping (2) simplifies the handling of function calls.
++ */
++static const u8 bpf2mips32[][2] = {
++	/* Return value from in-kernel function, and exit value from eBPF */
++	[BPF_REG_0] = {MIPS_R_V1, MIPS_R_V0},
++	/* Arguments from eBPF program to in-kernel function */
++	[BPF_REG_1] = {MIPS_R_A1, MIPS_R_A0},
++	[BPF_REG_2] = {MIPS_R_A3, MIPS_R_A2},
++	/* Remaining arguments, to be passed on the stack per O32 ABI */
++	[BPF_REG_3] = {MIPS_R_T1, MIPS_R_T0},
++	[BPF_REG_4] = {MIPS_R_T3, MIPS_R_T2},
++	[BPF_REG_5] = {MIPS_R_T5, MIPS_R_T4},
++	/* Callee-saved registers that in-kernel function will preserve */
++	[BPF_REG_6] = {MIPS_R_S1, MIPS_R_S0},
++	[BPF_REG_7] = {MIPS_R_S3, MIPS_R_S2},
++	[BPF_REG_8] = {MIPS_R_S5, MIPS_R_S4},
++	[BPF_REG_9] = {MIPS_R_S7, MIPS_R_S6},
++	/* Read-only frame pointer to access the eBPF stack */
++#ifdef __BIG_ENDIAN
++	[BPF_REG_FP] = {MIPS_R_FP, MIPS_R_ZERO},
++#else
++	[BPF_REG_FP] = {MIPS_R_ZERO, MIPS_R_FP},
++#endif
++	/* Temporary register for blinding constants */
++	[BPF_REG_AX] = {MIPS_R_GP, MIPS_R_AT},
++	/* Temporary register for internal JIT use */
++	[JIT_REG_TMP] = {MIPS_R_T7, MIPS_R_T6},
++};
++
++/* Get low CPU register for a 64-bit eBPF register mapping */
++static inline u8 lo(const u8 reg[])
++{
++#ifdef __BIG_ENDIAN
++	return reg[0];
++#else
++	return reg[1];
++#endif
++}
++
++/* Get high CPU register for a 64-bit eBPF register mapping */
++static inline u8 hi(const u8 reg[])
++{
++#ifdef __BIG_ENDIAN
++	return reg[1];
++#else
++	return reg[0];
++#endif
++}
++
++/*
++ * Mark a 64-bit CPU register pair as clobbered, it needs to be
++ * saved/restored by the program if callee-saved.
++ */
++static void clobber_reg64(struct jit_context *ctx, const u8 reg[])
++{
++	clobber_reg(ctx, reg[0]);
++	clobber_reg(ctx, reg[1]);
++}
++
++/* dst = imm (sign-extended) */
++static void emit_mov_se_i64(struct jit_context *ctx, const u8 dst[], s32 imm)
++{
++	emit_mov_i(ctx, lo(dst), imm);
++	if (imm < 0)
++		emit(ctx, addiu, hi(dst), MIPS_R_ZERO, -1);
++	else
++		emit(ctx, move, hi(dst), MIPS_R_ZERO);
++	clobber_reg64(ctx, dst);
++}
++
++/* Zero extension, if verifier does not do it for us  */
++static void emit_zext_ver(struct jit_context *ctx, const u8 dst[])
++{
++	if (!ctx->program->aux->verifier_zext) {
++		emit(ctx, move, hi(dst), MIPS_R_ZERO);
++		clobber_reg(ctx, hi(dst));
++	}
++}
++
++/* Load delay slot, if ISA mandates it */
++static void emit_load_delay(struct jit_context *ctx)
++{
++	if (!cpu_has_mips_2_3_4_5_r)
++		emit(ctx, nop);
++}
++
++/* ALU immediate operation (64-bit) */
++static void emit_alu_i64(struct jit_context *ctx,
++			 const u8 dst[], s32 imm, u8 op)
++{
++	u8 src = MIPS_R_T6;
++
++	/*
++	 * ADD/SUB with all but the max negative imm can be handled by
++	 * inverting the operation and the imm value, saving one insn.
++	 */
++	if (imm > S32_MIN && imm < 0)
++		switch (op) {
++		case BPF_ADD:
++			op = BPF_SUB;
++			imm = -imm;
++			break;
++		case BPF_SUB:
++			op = BPF_ADD;
++			imm = -imm;
++			break;
++		}
++
++	/* Move immediate to temporary register */
++	emit_mov_i(ctx, src, imm);
++
++	switch (op) {
++	/* dst = dst + imm */
++	case BPF_ADD:
++		emit(ctx, addu, lo(dst), lo(dst), src);
++		emit(ctx, sltu, MIPS_R_T9, lo(dst), src);
++		emit(ctx, addu, hi(dst), hi(dst), MIPS_R_T9);
++		if (imm < 0)
++			emit(ctx, addiu, hi(dst), hi(dst), -1);
++		break;
++	/* dst = dst - imm */
++	case BPF_SUB:
++		emit(ctx, sltu, MIPS_R_T9, lo(dst), src);
++		emit(ctx, subu, lo(dst), lo(dst), src);
++		emit(ctx, subu, hi(dst), hi(dst), MIPS_R_T9);
++		if (imm < 0)
++			emit(ctx, addiu, hi(dst), hi(dst), 1);
++		break;
++	/* dst = dst | imm */
++	case BPF_OR:
++		emit(ctx, or, lo(dst), lo(dst), src);
++		if (imm < 0)
++			emit(ctx, addiu, hi(dst), MIPS_R_ZERO, -1);
++		break;
++	/* dst = dst & imm */
++	case BPF_AND:
++		emit(ctx, and, lo(dst), lo(dst), src);
++		if (imm >= 0)
++			emit(ctx, move, hi(dst), MIPS_R_ZERO);
++		break;
++	/* dst = dst ^ imm */
++	case BPF_XOR:
++		emit(ctx, xor, lo(dst), lo(dst), src);
++		if (imm < 0) {
++			emit(ctx, subu, hi(dst), MIPS_R_ZERO, hi(dst));
++			emit(ctx, addiu, hi(dst), hi(dst), -1);
++		}
++		break;
++	}
++	clobber_reg64(ctx, dst);
++}
++
++/* ALU register operation (64-bit) */
++static void emit_alu_r64(struct jit_context *ctx,
++			 const u8 dst[], const u8 src[], u8 op)
++{
++	switch (BPF_OP(op)) {
++	/* dst = dst + src */
++	case BPF_ADD:
++		if (src == dst) {
++			emit(ctx, srl, MIPS_R_T9, lo(dst), 31);
++			emit(ctx, addu, lo(dst), lo(dst), lo(dst));
++		} else {
++			emit(ctx, addu, lo(dst), lo(dst), lo(src));
++			emit(ctx, sltu, MIPS_R_T9, lo(dst), lo(src));
++		}
++		emit(ctx, addu, hi(dst), hi(dst), hi(src));
++		emit(ctx, addu, hi(dst), hi(dst), MIPS_R_T9);
++		break;
++	/* dst = dst - src */
++	case BPF_SUB:
++		emit(ctx, sltu, MIPS_R_T9, lo(dst), lo(src));
++		emit(ctx, subu, lo(dst), lo(dst), lo(src));
++		emit(ctx, subu, hi(dst), hi(dst), hi(src));
++		emit(ctx, subu, hi(dst), hi(dst), MIPS_R_T9);
++		break;
++	/* dst = dst | src */
++	case BPF_OR:
++		emit(ctx, or, lo(dst), lo(dst), lo(src));
++		emit(ctx, or, hi(dst), hi(dst), hi(src));
++		break;
++	/* dst = dst & src */
++	case BPF_AND:
++		emit(ctx, and, lo(dst), lo(dst), lo(src));
++		emit(ctx, and, hi(dst), hi(dst), hi(src));
++		break;
++	/* dst = dst ^ src */
++	case BPF_XOR:
++		emit(ctx, xor, lo(dst), lo(dst), lo(src));
++		emit(ctx, xor, hi(dst), hi(dst), hi(src));
++		break;
++	}
++	clobber_reg64(ctx, dst);
++}
++
++/* ALU invert (64-bit) */
++static void emit_neg_i64(struct jit_context *ctx, const u8 dst[])
++{
++	emit(ctx, sltu, MIPS_R_T9, MIPS_R_ZERO, lo(dst));
++	emit(ctx, subu, lo(dst), MIPS_R_ZERO, lo(dst));
++	emit(ctx, subu, hi(dst), MIPS_R_ZERO, hi(dst));
++	emit(ctx, subu, hi(dst), hi(dst), MIPS_R_T9);
++
++	clobber_reg64(ctx, dst);
++}
++
++/* ALU shift immediate (64-bit) */
++static void emit_shift_i64(struct jit_context *ctx,
++			   const u8 dst[], u32 imm, u8 op)
++{
++	switch (BPF_OP(op)) {
++	/* dst = dst << imm */
++	case BPF_LSH:
++		if (imm < 32) {
++			emit(ctx, srl, MIPS_R_T9, lo(dst), 32 - imm);
++			emit(ctx, sll, lo(dst), lo(dst), imm);
++			emit(ctx, sll, hi(dst), hi(dst), imm);
++			emit(ctx, or, hi(dst), hi(dst), MIPS_R_T9);
++		} else {
++			emit(ctx, sll, hi(dst), lo(dst), imm - 32);
++			emit(ctx, move, lo(dst), MIPS_R_ZERO);
++		}
++		break;
++	/* dst = dst >> imm */
++	case BPF_RSH:
++		if (imm < 32) {
++			emit(ctx, sll, MIPS_R_T9, hi(dst), 32 - imm);
++			emit(ctx, srl, lo(dst), lo(dst), imm);
++			emit(ctx, srl, hi(dst), hi(dst), imm);
++			emit(ctx, or, lo(dst), lo(dst), MIPS_R_T9);
++		} else {
++			emit(ctx, srl, lo(dst), hi(dst), imm - 32);
++			emit(ctx, move, hi(dst), MIPS_R_ZERO);
++		}
++		break;
++	/* dst = dst >> imm (arithmetic) */
++	case BPF_ARSH:
++		if (imm < 32) {
++			emit(ctx, sll, MIPS_R_T9, hi(dst), 32 - imm);
++			emit(ctx, srl, lo(dst), lo(dst), imm);
++			emit(ctx, sra, hi(dst), hi(dst), imm);
++			emit(ctx, or, lo(dst), lo(dst), MIPS_R_T9);
++		} else {
++			emit(ctx, sra, lo(dst), hi(dst), imm - 32);
++			emit(ctx, sra, hi(dst), hi(dst), 31);
++		}
++		break;
++	}
++	clobber_reg64(ctx, dst);
++}
++
++/* ALU shift register (64-bit) */
++static void emit_shift_r64(struct jit_context *ctx,
++			   const u8 dst[], u8 src, u8 op)
++{
++	u8 t1 = MIPS_R_T8;
++	u8 t2 = MIPS_R_T9;
++
++	emit(ctx, andi, t1, src, 32);              /* t1 = src & 32          */
++	emit(ctx, beqz, t1, 16);                   /* PC += 16 if t1 == 0    */
++	emit(ctx, nor, t2, src, MIPS_R_ZERO);      /* t2 = ~src (delay slot) */
++
++	switch (BPF_OP(op)) {
++	/* dst = dst << src */
++	case BPF_LSH:
++		/* Next: shift >= 32 */
++		emit(ctx, sllv, hi(dst), lo(dst), src);    /* dh = dl << src */
++		emit(ctx, move, lo(dst), MIPS_R_ZERO);     /* dl = 0         */
++		emit(ctx, b, 20);                          /* PC += 20       */
++		/* +16: shift < 32 */
++		emit(ctx, srl, t1, lo(dst), 1);            /* t1 = dl >> 1   */
++		emit(ctx, srlv, t1, t1, t2);               /* t1 = t1 >> t2  */
++		emit(ctx, sllv, lo(dst), lo(dst), src);    /* dl = dl << src */
++		emit(ctx, sllv, hi(dst), hi(dst), src);    /* dh = dh << src */
++		emit(ctx, or, hi(dst), hi(dst), t1);       /* dh = dh | t1   */
++		break;
++	/* dst = dst >> src */
++	case BPF_RSH:
++		/* Next: shift >= 32 */
++		emit(ctx, srlv, lo(dst), hi(dst), src);    /* dl = dh >> src */
++		emit(ctx, move, hi(dst), MIPS_R_ZERO);     /* dh = 0         */
++		emit(ctx, b, 20);                          /* PC += 20       */
++		/* +16: shift < 32 */
++		emit(ctx, sll, t1, hi(dst), 1);            /* t1 = dl << 1   */
++		emit(ctx, sllv, t1, t1, t2);               /* t1 = t1 << t2  */
++		emit(ctx, srlv, lo(dst), lo(dst), src);    /* dl = dl >> src */
++		emit(ctx, srlv, hi(dst), hi(dst), src);    /* dh = dh >> src */
++		emit(ctx, or, lo(dst), lo(dst), t1);       /* dl = dl | t1   */
++		break;
++	/* dst = dst >> src (arithmetic) */
++	case BPF_ARSH:
++		/* Next: shift >= 32 */
++		emit(ctx, srav, lo(dst), hi(dst), src);   /* dl = dh >>a src */
++		emit(ctx, sra, hi(dst), hi(dst), 31);     /* dh = dh >>a 31  */
++		emit(ctx, b, 20);                         /* PC += 20        */
++		/* +16: shift < 32 */
++		emit(ctx, sll, t1, hi(dst), 1);           /* t1 = dl << 1    */
++		emit(ctx, sllv, t1, t1, t2);              /* t1 = t1 << t2   */
++		emit(ctx, srlv, lo(dst), lo(dst), src);   /* dl = dl >>a src */
++		emit(ctx, srav, hi(dst), hi(dst), src);   /* dh = dh >> src  */
++		emit(ctx, or, lo(dst), lo(dst), t1);      /* dl = dl | t1    */
++		break;
++	}
++
++	/* +20: Done */
++	clobber_reg64(ctx, dst);
++}
++
++/* ALU mul immediate (64x32-bit) */
++static void emit_mul_i64(struct jit_context *ctx, const u8 dst[], s32 imm)
++{
++	u8 src = MIPS_R_T6;
++	u8 tmp = MIPS_R_T9;
++
++	switch (imm) {
++	/* dst = dst * 1 is a no-op */
++	case 1:
++		break;
++	/* dst = dst * -1 */
++	case -1:
++		emit_neg_i64(ctx, dst);
++		break;
++	case 0:
++		emit_mov_r(ctx, lo(dst), MIPS_R_ZERO);
++		emit_mov_r(ctx, hi(dst), MIPS_R_ZERO);
++		break;
++	/* Full 64x32 multiply */
++	default:
++		/* hi(dst) = hi(dst) * src(imm) */
++		emit_mov_i(ctx, src, imm);
++		if (cpu_has_mips32r1 || cpu_has_mips32r6) {
++			emit(ctx, mul, hi(dst), hi(dst), src);
++		} else {
++			emit(ctx, multu, hi(dst), src);
++			emit(ctx, mflo, hi(dst));
++		}
++
++		/* hi(dst) = hi(dst) - lo(dst) */
++		if (imm < 0)
++			emit(ctx, subu, hi(dst), hi(dst), lo(dst));
++
++		/* tmp = lo(dst) * src(imm) >> 32 */
++		/* lo(dst) = lo(dst) * src(imm) */
++		if (cpu_has_mips32r6) {
++			emit(ctx, muhu, tmp, lo(dst), src);
++			emit(ctx, mulu, lo(dst), lo(dst), src);
++		} else {
++			emit(ctx, multu, lo(dst), src);
++			emit(ctx, mflo, lo(dst));
++			emit(ctx, mfhi, tmp);
++		}
++
++		/* hi(dst) += tmp */
++		emit(ctx, addu, hi(dst), hi(dst), tmp);
++		clobber_reg64(ctx, dst);
++		break;
++	}
++}
++
++/* ALU mul register (64x64-bit) */
++static void emit_mul_r64(struct jit_context *ctx,
++			 const u8 dst[], const u8 src[])
++{
++	u8 acc = MIPS_R_T8;
++	u8 tmp = MIPS_R_T9;
++
++	/* acc = hi(dst) * lo(src) */
++	if (cpu_has_mips32r1 || cpu_has_mips32r6) {
++		emit(ctx, mul, acc, hi(dst), lo(src));
++	} else {
++		emit(ctx, multu, hi(dst), lo(src));
++		emit(ctx, mflo, acc);
++	}
++
++	/* tmp = lo(dst) * hi(src) */
++	if (cpu_has_mips32r1 || cpu_has_mips32r6) {
++		emit(ctx, mul, tmp, lo(dst), hi(src));
++	} else {
++		emit(ctx, multu, lo(dst), hi(src));
++		emit(ctx, mflo, tmp);
++	}
++
++	/* acc += tmp */
++	emit(ctx, addu, acc, acc, tmp);
++
++	/* tmp = lo(dst) * lo(src) >> 32 */
++	/* lo(dst) = lo(dst) * lo(src) */
++	if (cpu_has_mips32r6) {
++		emit(ctx, muhu, tmp, lo(dst), lo(src));
++		emit(ctx, mulu, lo(dst), lo(dst), lo(src));
++	} else {
++		emit(ctx, multu, lo(dst), lo(src));
++		emit(ctx, mflo, lo(dst));
++		emit(ctx, mfhi, tmp);
++	}
++
++	/* hi(dst) = acc + tmp */
++	emit(ctx, addu, hi(dst), acc, tmp);
++	clobber_reg64(ctx, dst);
++}
++
++/* Helper function for 64-bit modulo */
++static u64 jit_mod64(u64 a, u64 b)
++{
++	u64 rem;
++
++	div64_u64_rem(a, b, &rem);
++	return rem;
++}
++
++/* ALU div/mod register (64-bit) */
++static void emit_divmod_r64(struct jit_context *ctx,
++			    const u8 dst[], const u8 src[], u8 op)
++{
++	const u8 *r0 = bpf2mips32[BPF_REG_0]; /* Mapped to v0-v1 */
++	const u8 *r1 = bpf2mips32[BPF_REG_1]; /* Mapped to a0-a1 */
++	const u8 *r2 = bpf2mips32[BPF_REG_2]; /* Mapped to a2-a3 */
++	int exclude, k;
++	u32 addr = 0;
++
++	/* Push caller-saved registers on stack */
++	push_regs(ctx, ctx->clobbered & JIT_CALLER_REGS,
++		  0, JIT_RESERVED_STACK);
++
++	/* Put 64-bit arguments 1 and 2 in registers a0-a3 */
++	for (k = 0; k < 2; k++) {
++		emit(ctx, move, MIPS_R_T9, src[k]);
++		emit(ctx, move, r1[k], dst[k]);
++		emit(ctx, move, r2[k], MIPS_R_T9);
++	}
++
++	/* Emit function call */
++	switch (BPF_OP(op)) {
++	/* dst = dst / src */
++	case BPF_DIV:
++		addr = (u32)&div64_u64;
++		break;
++	/* dst = dst % src */
++	case BPF_MOD:
++		addr = (u32)&jit_mod64;
++		break;
++	}
++	emit_mov_i(ctx, MIPS_R_T9, addr);
++	emit(ctx, jalr, MIPS_R_RA, MIPS_R_T9);
++	emit(ctx, nop); /* Delay slot */
++
++	/* Store the 64-bit result in dst */
++	emit(ctx, move, dst[0], r0[0]);
++	emit(ctx, move, dst[1], r0[1]);
++
++	/* Restore caller-saved registers, excluding the computed result */
++	exclude = BIT(lo(dst)) | BIT(hi(dst));
++	pop_regs(ctx, ctx->clobbered & JIT_CALLER_REGS,
++		 exclude, JIT_RESERVED_STACK);
++	emit_load_delay(ctx);
++
++	clobber_reg64(ctx, dst);
++	clobber_reg(ctx, MIPS_R_V0);
++	clobber_reg(ctx, MIPS_R_V1);
++	clobber_reg(ctx, MIPS_R_RA);
++}
++
++/* Swap bytes in a register word */
++static void emit_swap8_r(struct jit_context *ctx, u8 dst, u8 src, u8 mask)
++{
++	u8 tmp = MIPS_R_T9;
++
++	emit(ctx, and, tmp, src, mask); /* tmp = src & 0x00ff00ff */
++	emit(ctx, sll, tmp, tmp, 8);    /* tmp = tmp << 8         */
++	emit(ctx, srl, dst, src, 8);    /* dst = src >> 8         */
++	emit(ctx, and, dst, dst, mask); /* dst = dst & 0x00ff00ff */
++	emit(ctx, or,  dst, dst, tmp);  /* dst = dst | tmp        */
++}
++
++/* Swap half words in a register word */
++static void emit_swap16_r(struct jit_context *ctx, u8 dst, u8 src)
++{
++	u8 tmp = MIPS_R_T9;
++
++	emit(ctx, sll, tmp, src, 16);  /* tmp = src << 16 */
++	emit(ctx, srl, dst, src, 16);  /* dst = src >> 16 */
++	emit(ctx, or,  dst, dst, tmp); /* dst = dst | tmp */
++}
++
++/* Swap bytes and truncate a register double word, word or half word */
++static void emit_bswap_r64(struct jit_context *ctx, const u8 dst[], u32 width)
++{
++	u8 tmp = MIPS_R_T8;
++
++	switch (width) {
++	/* Swap bytes in a double word */
++	case 64:
++		if (cpu_has_mips32r2 || cpu_has_mips32r6) {
++			emit(ctx, rotr, tmp, hi(dst), 16);
++			emit(ctx, rotr, hi(dst), lo(dst), 16);
++			emit(ctx, wsbh, lo(dst), tmp);
++			emit(ctx, wsbh, hi(dst), hi(dst));
++		} else {
++			emit_swap16_r(ctx, tmp, lo(dst));
++			emit_swap16_r(ctx, lo(dst), hi(dst));
++			emit(ctx, move, hi(dst), tmp);
++
++			emit(ctx, lui, tmp, 0xff);      /* tmp = 0x00ff0000 */
++			emit(ctx, ori, tmp, tmp, 0xff); /* tmp = 0x00ff00ff */
++			emit_swap8_r(ctx, lo(dst), lo(dst), tmp);
++			emit_swap8_r(ctx, hi(dst), hi(dst), tmp);
++		}
++		break;
++	/* Swap bytes in a word */
++	/* Swap bytes in a half word */
++	case 32:
++	case 16:
++		emit_bswap_r(ctx, lo(dst), width);
++		emit(ctx, move, hi(dst), MIPS_R_ZERO);
++		break;
++	}
++	clobber_reg64(ctx, dst);
++}
++
++/* Truncate a register double word, word or half word */
++static void emit_trunc_r64(struct jit_context *ctx, const u8 dst[], u32 width)
++{
++	switch (width) {
++	case 64:
++		break;
++	/* Zero-extend a word */
++	case 32:
++		emit(ctx, move, hi(dst), MIPS_R_ZERO);
++		clobber_reg(ctx, hi(dst));
++		break;
++	/* Zero-extend a half word */
++	case 16:
++		emit(ctx, move, hi(dst), MIPS_R_ZERO);
++		emit(ctx, andi, lo(dst), lo(dst), 0xffff);
++		clobber_reg64(ctx, dst);
++		break;
++	}
++}
++
++/* Load operation: dst = *(size*)(src + off) */
++static void emit_ldx(struct jit_context *ctx,
++		     const u8 dst[], u8 src, s16 off, u8 size)
++{
++	switch (size) {
++	/* Load a byte */
++	case BPF_B:
++		emit(ctx, lbu, lo(dst), off, src);
++		emit(ctx, move, hi(dst), MIPS_R_ZERO);
++		break;
++	/* Load a half word */
++	case BPF_H:
++		emit(ctx, lhu, lo(dst), off, src);
++		emit(ctx, move, hi(dst), MIPS_R_ZERO);
++		break;
++	/* Load a word */
++	case BPF_W:
++		emit(ctx, lw, lo(dst), off, src);
++		emit(ctx, move, hi(dst), MIPS_R_ZERO);
++		break;
++	/* Load a double word */
++	case BPF_DW:
++		if (dst[1] == src) {
++			emit(ctx, lw, dst[0], off + 4, src);
++			emit(ctx, lw, dst[1], off, src);
++		} else {
++			emit(ctx, lw, dst[1], off, src);
++			emit(ctx, lw, dst[0], off + 4, src);
++		}
++		emit_load_delay(ctx);
++		break;
++	}
++	clobber_reg64(ctx, dst);
++}
++
++/* Store operation: *(size *)(dst + off) = src */
++static void emit_stx(struct jit_context *ctx,
++		     const u8 dst, const u8 src[], s16 off, u8 size)
++{
++	switch (size) {
++	/* Store a byte */
++	case BPF_B:
++		emit(ctx, sb, lo(src), off, dst);
++		break;
++	/* Store a half word */
++	case BPF_H:
++		emit(ctx, sh, lo(src), off, dst);
++		break;
++	/* Store a word */
++	case BPF_W:
++		emit(ctx, sw, lo(src), off, dst);
++		break;
++	/* Store a double word */
++	case BPF_DW:
++		emit(ctx, sw, src[1], off, dst);
++		emit(ctx, sw, src[0], off + 4, dst);
++		break;
++	}
++}
++
++/* Atomic read-modify-write (32-bit, non-ll/sc fallback) */
++static void emit_atomic_r32(struct jit_context *ctx,
++			    u8 dst, u8 src, s16 off, u8 code)
++{
++	u32 exclude = 0;
++	u32 addr = 0;
++
++	/* Push caller-saved registers on stack */
++	push_regs(ctx, ctx->clobbered & JIT_CALLER_REGS,
++		  0, JIT_RESERVED_STACK);
++	/*
++	 * Argument 1: dst+off if xchg, otherwise src, passed in register a0
++	 * Argument 2: src if xchg, othersize dst+off, passed in register a1
++	 */
++	emit(ctx, move, MIPS_R_T9, dst);
++	emit(ctx, move, MIPS_R_A0, src);
++	emit(ctx, addiu, MIPS_R_A1, MIPS_R_T9, off);
++
++	/* Emit function call */
++	switch (code) {
++	case BPF_ADD:
++		addr = (u32)&atomic_add;
++		break;
++	case BPF_SUB:
++		addr = (u32)&atomic_sub;
++		break;
++	case BPF_OR:
++		addr = (u32)&atomic_or;
++		break;
++	case BPF_AND:
++		addr = (u32)&atomic_and;
++		break;
++	case BPF_XOR:
++		addr = (u32)&atomic_xor;
++		break;
++	}
++	emit_mov_i(ctx, MIPS_R_T9, addr);
++	emit(ctx, jalr, MIPS_R_RA, MIPS_R_T9);
++	emit(ctx, nop); /* Delay slot */
++
++	/* Restore caller-saved registers, except any fetched value */
++	pop_regs(ctx, ctx->clobbered & JIT_CALLER_REGS,
++		 exclude, JIT_RESERVED_STACK);
++	emit_load_delay(ctx);
++	clobber_reg(ctx, MIPS_R_RA);
++}
++
++/* Atomic read-modify-write (64-bit) */
++static void emit_atomic_r64(struct jit_context *ctx,
++			    u8 dst, const u8 src[], s16 off, u8 code)
++{
++	const u8 *r1 = bpf2mips32[BPF_REG_1]; /* Mapped to a0-a1 */
++	u32 exclude = 0;
++	u32 addr = 0;
++
++	/* Push caller-saved registers on stack */
++	push_regs(ctx, ctx->clobbered & JIT_CALLER_REGS,
++		  0, JIT_RESERVED_STACK);
++	/*
++	 * Argument 1: 64-bit src, passed in registers a0-a1
++	 * Argument 2: 32-bit dst+off, passed in register a2
++	 */
++	emit(ctx, move, MIPS_R_T9, dst);
++	emit(ctx, move, r1[0], src[0]);
++	emit(ctx, move, r1[1], src[1]);
++	emit(ctx, addiu, MIPS_R_A2, MIPS_R_T9, off);
++
++	/* Emit function call */
++	switch (code) {
++	case BPF_ADD:
++		addr = (u32)&atomic64_add;
++		break;
++	case BPF_SUB:
++		addr = (u32)&atomic64_sub;
++		break;
++	case BPF_OR:
++		addr = (u32)&atomic64_or;
++		break;
++	case BPF_AND:
++		addr = (u32)&atomic64_and;
++		break;
++	case BPF_XOR:
++		addr = (u32)&atomic64_xor;
++		break;
++	}
++	emit_mov_i(ctx, MIPS_R_T9, addr);
++	emit(ctx, jalr, MIPS_R_RA, MIPS_R_T9);
++	emit(ctx, nop); /* Delay slot */
++
++	/* Restore caller-saved registers, except any fetched value */
++	pop_regs(ctx, ctx->clobbered & JIT_CALLER_REGS,
++		 exclude, JIT_RESERVED_STACK);
++	emit_load_delay(ctx);
++	clobber_reg(ctx, MIPS_R_RA);
++}
++
++/*
++ * Conditional movz or an emulated equivalent.
++ * Note that the rs register may be modified.
++ */
++static void emit_movz_r(struct jit_context *ctx, u8 rd, u8 rs, u8 rt)
++{
++	if (cpu_has_mips_2) {
++		emit(ctx, movz, rd, rs, rt);           /* rd = rt ? rd : rs  */
++	} else if (cpu_has_mips32r6) {
++		if (rs != MIPS_R_ZERO)
++			emit(ctx, seleqz, rs, rs, rt); /* rs = 0 if rt == 0  */
++		emit(ctx, selnez, rd, rd, rt);         /* rd = 0 if rt != 0  */
++		if (rs != MIPS_R_ZERO)
++			emit(ctx, or, rd, rd, rs);     /* rd = rd | rs       */
++	} else {
++		emit(ctx, bnez, rt, 8);                /* PC += 8 if rd != 0 */
++		emit(ctx, nop);                        /* +0: delay slot     */
++		emit(ctx, or, rd, rs, MIPS_R_ZERO);    /* +4: rd = rs        */
++	}
++	clobber_reg(ctx, rd);
++	clobber_reg(ctx, rs);
++}
++
++/*
++ * Conditional movn or an emulated equivalent.
++ * Note that the rs register may be modified.
++ */
++static void emit_movn_r(struct jit_context *ctx, u8 rd, u8 rs, u8 rt)
++{
++	if (cpu_has_mips_2) {
++		emit(ctx, movn, rd, rs, rt);           /* rd = rt ? rs : rd  */
++	} else if (cpu_has_mips32r6) {
++		if (rs != MIPS_R_ZERO)
++			emit(ctx, selnez, rs, rs, rt); /* rs = 0 if rt == 0  */
++		emit(ctx, seleqz, rd, rd, rt);         /* rd = 0 if rt != 0  */
++		if (rs != MIPS_R_ZERO)
++			emit(ctx, or, rd, rd, rs);     /* rd = rd | rs       */
++	} else {
++		emit(ctx, beqz, rt, 8);                /* PC += 8 if rd == 0 */
++		emit(ctx, nop);                        /* +0: delay slot     */
++		emit(ctx, or, rd, rs, MIPS_R_ZERO);    /* +4: rd = rs        */
++	}
++	clobber_reg(ctx, rd);
++	clobber_reg(ctx, rs);
++}
++
++/* Emulation of 64-bit sltiu rd, rs, imm, where imm may be S32_MAX + 1 */
++static void emit_sltiu_r64(struct jit_context *ctx, u8 rd,
++			   const u8 rs[], s64 imm)
++{
++	u8 tmp = MIPS_R_T9;
++
++	if (imm < 0) {
++		emit_mov_i(ctx, rd, imm);                 /* rd = imm        */
++		emit(ctx, sltu, rd, lo(rs), rd);          /* rd = rsl < rd   */
++		emit(ctx, sltiu, tmp, hi(rs), -1);        /* tmp = rsh < ~0U */
++		emit(ctx, or, rd, rd, tmp);               /* rd = rd | tmp   */
++	} else { /* imm >= 0 */
++		if (imm > 0x7fff) {
++			emit_mov_i(ctx, rd, (s32)imm);     /* rd = imm       */
++			emit(ctx, sltu, rd, lo(rs), rd);   /* rd = rsl < rd  */
++		} else {
++			emit(ctx, sltiu, rd, lo(rs), imm); /* rd = rsl < imm */
++		}
++		emit_movn_r(ctx, rd, MIPS_R_ZERO, hi(rs)); /* rd = 0 if rsh  */
++	}
++}
++
++/* Emulation of 64-bit sltu rd, rs, rt */
++static void emit_sltu_r64(struct jit_context *ctx, u8 rd,
++			  const u8 rs[], const u8 rt[])
++{
++	u8 tmp = MIPS_R_T9;
++
++	emit(ctx, sltu, rd, lo(rs), lo(rt));           /* rd = rsl < rtl     */
++	emit(ctx, subu, tmp, hi(rs), hi(rt));          /* tmp = rsh - rth    */
++	emit_movn_r(ctx, rd, MIPS_R_ZERO, tmp);        /* rd = 0 if tmp != 0 */
++	emit(ctx, sltu, tmp, hi(rs), hi(rt));          /* tmp = rsh < rth    */
++	emit(ctx, or, rd, rd, tmp);                    /* rd = rd | tmp      */
++}
++
++/* Emulation of 64-bit slti rd, rs, imm, where imm may be S32_MAX + 1 */
++static void emit_slti_r64(struct jit_context *ctx, u8 rd,
++			  const u8 rs[], s64 imm)
++{
++	u8 t1 = MIPS_R_T8;
++	u8 t2 = MIPS_R_T9;
++	u8 cmp;
++
++	/*
++	 * if ((rs < 0) ^ (imm < 0)) t1 = imm >u rsl
++	 * else                      t1 = rsl <u imm
++	 */
++	emit_mov_i(ctx, rd, (s32)imm);
++	emit(ctx, sltu, t1, lo(rs), rd);               /* t1 = rsl <u imm   */
++	emit(ctx, sltu, t2, rd, lo(rs));               /* t2 = imm <u rsl   */
++	emit(ctx, srl, rd, hi(rs), 31);                /* rd = rsh >> 31    */
++	if (imm < 0)
++		emit_movz_r(ctx, t1, t2, rd);          /* t1 = rd ? t1 : t2 */
++	else
++		emit_movn_r(ctx, t1, t2, rd);          /* t1 = rd ? t2 : t1 */
++	/*
++	 * if ((imm < 0 && rsh != 0xffffffff) ||
++	 *     (imm >= 0 && rsh != 0))
++	 *      t1 = 0
++	 */
++	if (imm < 0) {
++		emit(ctx, addiu, rd, hi(rs), 1);       /* rd = rsh + 1 */
++		cmp = rd;
++	} else { /* imm >= 0 */
++		cmp = hi(rs);
++	}
++	emit_movn_r(ctx, t1, MIPS_R_ZERO, cmp);        /* t1 = 0 if cmp != 0 */
++
++	/*
++	 * if (imm < 0) rd = rsh < -1
++	 * else         rd = rsh != 0
++	 * rd = rd | t1
++	 */
++	emit(ctx, slti, rd, hi(rs), imm < 0 ? -1 : 0); /* rd = rsh < hi(imm) */
++	emit(ctx, or, rd, rd, t1);                     /* rd = rd | t1       */
++}
++
++/* Emulation of 64-bit(slt rd, rs, rt) */
++static void emit_slt_r64(struct jit_context *ctx, u8 rd,
++			 const u8 rs[], const u8 rt[])
++{
++	u8 t1 = MIPS_R_T7;
++	u8 t2 = MIPS_R_T8;
++	u8 t3 = MIPS_R_T9;
++
++	/*
++	 * if ((rs < 0) ^ (rt < 0)) t1 = rtl <u rsl
++	 * else                     t1 = rsl <u rtl
++	 * if (rsh == rth)          t1 = 0
++	 */
++	emit(ctx, sltu, t1, lo(rs), lo(rt));           /* t1 = rsl <u rtl   */
++	emit(ctx, sltu, t2, lo(rt), lo(rs));           /* t2 = rtl <u rsl   */
++	emit(ctx, xor, t3, hi(rs), hi(rt));            /* t3 = rlh ^ rth    */
++	emit(ctx, srl, rd, t3, 31);                    /* rd = t3 >> 31     */
++	emit_movn_r(ctx, t1, t2, rd);                  /* t1 = rd ? t2 : t1 */
++	emit_movn_r(ctx, t1, MIPS_R_ZERO, t3);         /* t1 = 0 if t3 != 0 */
++
++	/* rd = (rsh < rth) | t1 */
++	emit(ctx, slt, rd, hi(rs), hi(rt));            /* rd = rsh <s rth   */
++	emit(ctx, or, rd, rd, t1);                     /* rd = rd | t1      */
++}
++
++/* Jump immediate (64-bit) */
++static void emit_jmp_i64(struct jit_context *ctx,
++			 const u8 dst[], s32 imm, s32 off, u8 op)
++{
++	u8 tmp = MIPS_R_T6;
++
++	switch (op) {
++	/* No-op, used internally for branch optimization */
++	case JIT_JNOP:
++		break;
++	/* PC += off if dst == imm */
++	/* PC += off if dst != imm */
++	case BPF_JEQ:
++	case BPF_JNE:
++		if (imm >= -0x7fff && imm <= 0x8000) {
++			emit(ctx, addiu, tmp, lo(dst), -imm);
++		} else if ((u32)imm <= 0xffff) {
++			emit(ctx, xori, tmp, lo(dst), imm);
++		} else {       /* Register fallback */
++			emit_mov_i(ctx, tmp, imm);
++			emit(ctx, xor, tmp, lo(dst), tmp);
++		}
++		if (imm < 0) { /* Compare sign extension */
++			emit(ctx, addu, MIPS_R_T9, hi(dst), 1);
++			emit(ctx, or, tmp, tmp, MIPS_R_T9);
++		} else {       /* Compare zero extension */
++			emit(ctx, or, tmp, tmp, hi(dst));
++		}
++		if (op == BPF_JEQ)
++			emit(ctx, beqz, tmp, off);
++		else   /* BPF_JNE */
++			emit(ctx, bnez, tmp, off);
++		break;
++	/* PC += off if dst & imm */
++	/* PC += off if (dst & imm) == 0 (not in BPF, used for long jumps) */
++	case BPF_JSET:
++	case JIT_JNSET:
++		if ((u32)imm <= 0xffff) {
++			emit(ctx, andi, tmp, lo(dst), imm);
++		} else {     /* Register fallback */
++			emit_mov_i(ctx, tmp, imm);
++			emit(ctx, and, tmp, lo(dst), tmp);
++		}
++		if (imm < 0) /* Sign-extension pulls in high word */
++			emit(ctx, or, tmp, tmp, hi(dst));
++		if (op == BPF_JSET)
++			emit(ctx, bnez, tmp, off);
++		else   /* JIT_JNSET */
++			emit(ctx, beqz, tmp, off);
++		break;
++	/* PC += off if dst > imm */
++	case BPF_JGT:
++		emit_sltiu_r64(ctx, tmp, dst, (s64)imm + 1);
++		emit(ctx, beqz, tmp, off);
++		break;
++	/* PC += off if dst >= imm */
++	case BPF_JGE:
++		emit_sltiu_r64(ctx, tmp, dst, imm);
++		emit(ctx, beqz, tmp, off);
++		break;
++	/* PC += off if dst < imm */
++	case BPF_JLT:
++		emit_sltiu_r64(ctx, tmp, dst, imm);
++		emit(ctx, bnez, tmp, off);
++		break;
++	/* PC += off if dst <= imm */
++	case BPF_JLE:
++		emit_sltiu_r64(ctx, tmp, dst, (s64)imm + 1);
++		emit(ctx, bnez, tmp, off);
++		break;
++	/* PC += off if dst > imm (signed) */
++	case BPF_JSGT:
++		emit_slti_r64(ctx, tmp, dst, (s64)imm + 1);
++		emit(ctx, beqz, tmp, off);
++		break;
++	/* PC += off if dst >= imm (signed) */
++	case BPF_JSGE:
++		emit_slti_r64(ctx, tmp, dst, imm);
++		emit(ctx, beqz, tmp, off);
++		break;
++	/* PC += off if dst < imm (signed) */
++	case BPF_JSLT:
++		emit_slti_r64(ctx, tmp, dst, imm);
++		emit(ctx, bnez, tmp, off);
++		break;
++	/* PC += off if dst <= imm (signed) */
++	case BPF_JSLE:
++		emit_slti_r64(ctx, tmp, dst, (s64)imm + 1);
++		emit(ctx, bnez, tmp, off);
++		break;
++	}
++}
++
++/* Jump register (64-bit) */
++static void emit_jmp_r64(struct jit_context *ctx,
++			 const u8 dst[], const u8 src[], s32 off, u8 op)
++{
++	u8 t1 = MIPS_R_T6;
++	u8 t2 = MIPS_R_T7;
++
++	switch (op) {
++	/* No-op, used internally for branch optimization */
++	case JIT_JNOP:
++		break;
++	/* PC += off if dst == src */
++	/* PC += off if dst != src */
++	case BPF_JEQ:
++	case BPF_JNE:
++		emit(ctx, subu, t1, lo(dst), lo(src));
++		emit(ctx, subu, t2, hi(dst), hi(src));
++		emit(ctx, or, t1, t1, t2);
++		if (op == BPF_JEQ)
++			emit(ctx, beqz, t1, off);
++		else   /* BPF_JNE */
++			emit(ctx, bnez, t1, off);
++		break;
++	/* PC += off if dst & src */
++	/* PC += off if (dst & imm) == 0 (not in BPF, used for long jumps) */
++	case BPF_JSET:
++	case JIT_JNSET:
++		emit(ctx, and, t1, lo(dst), lo(src));
++		emit(ctx, and, t2, hi(dst), hi(src));
++		emit(ctx, or, t1, t1, t2);
++		if (op == BPF_JSET)
++			emit(ctx, bnez, t1, off);
++		else   /* JIT_JNSET */
++			emit(ctx, beqz, t1, off);
++		break;
++	/* PC += off if dst > src */
++	case BPF_JGT:
++		emit_sltu_r64(ctx, t1, src, dst);
++		emit(ctx, bnez, t1, off);
++		break;
++	/* PC += off if dst >= src */
++	case BPF_JGE:
++		emit_sltu_r64(ctx, t1, dst, src);
++		emit(ctx, beqz, t1, off);
++		break;
++	/* PC += off if dst < src */
++	case BPF_JLT:
++		emit_sltu_r64(ctx, t1, dst, src);
++		emit(ctx, bnez, t1, off);
++		break;
++	/* PC += off if dst <= src */
++	case BPF_JLE:
++		emit_sltu_r64(ctx, t1, src, dst);
++		emit(ctx, beqz, t1, off);
++		break;
++	/* PC += off if dst > src (signed) */
++	case BPF_JSGT:
++		emit_slt_r64(ctx, t1, src, dst);
++		emit(ctx, bnez, t1, off);
++		break;
++	/* PC += off if dst >= src (signed) */
++	case BPF_JSGE:
++		emit_slt_r64(ctx, t1, dst, src);
++		emit(ctx, beqz, t1, off);
++		break;
++	/* PC += off if dst < src (signed) */
++	case BPF_JSLT:
++		emit_slt_r64(ctx, t1, dst, src);
++		emit(ctx, bnez, t1, off);
++		break;
++	/* PC += off if dst <= src (signed) */
++	case BPF_JSLE:
++		emit_slt_r64(ctx, t1, src, dst);
++		emit(ctx, beqz, t1, off);
++		break;
++	}
++}
++
++/* Function call */
++static int emit_call(struct jit_context *ctx, const struct bpf_insn *insn)
++{
++	bool fixed;
++	u64 addr;
++
++	/* Decode the call address */
++	if (bpf_jit_get_func_addr(ctx->program, insn, false,
++				  &addr, &fixed) < 0)
++		return -1;
++	if (!fixed)
++		return -1;
++
++	/* Push stack arguments */
++	push_regs(ctx, JIT_STACK_REGS, 0, JIT_RESERVED_STACK);
++
++	/* Emit function call */
++	emit_mov_i(ctx, MIPS_R_T9, addr);
++	emit(ctx, jalr, MIPS_R_RA, MIPS_R_T9);
++	emit(ctx, nop); /* Delay slot */
++
++	clobber_reg(ctx, MIPS_R_RA);
++	clobber_reg(ctx, MIPS_R_V0);
++	clobber_reg(ctx, MIPS_R_V1);
++	return 0;
++}
++
++/* Function tail call */
++static int emit_tail_call(struct jit_context *ctx)
++{
++	u8 ary = lo(bpf2mips32[BPF_REG_2]);
++	u8 ind = lo(bpf2mips32[BPF_REG_3]);
++	u8 t1 = MIPS_R_T8;
++	u8 t2 = MIPS_R_T9;
++	int off;
++
++	/*
++	 * Tail call:
++	 * eBPF R1   - function argument (context ptr), passed in a0-a1
++	 * eBPF R2   - ptr to object with array of function entry points
++	 * eBPF R3   - array index of function to be called
++	 * stack[sz] - remaining tail call count, initialized in prologue
++	 */
++
++	/* if (ind >= ary->map.max_entries) goto out */
++	off = offsetof(struct bpf_array, map.max_entries);
++	if (off > 0x7fff)
++		return -1;
++	emit(ctx, lw, t1, off, ary);             /* t1 = ary->map.max_entries*/
++	emit_load_delay(ctx);                    /* Load delay slot          */
++	emit(ctx, sltu, t1, ind, t1);            /* t1 = ind < t1            */
++	emit(ctx, beqz, t1, get_offset(ctx, 1)); /* PC += off(1) if t1 == 0  */
++						 /* (next insn delay slot)   */
++	/* if (TCC-- <= 0) goto out */
++	emit(ctx, lw, t2, ctx->stack_size, MIPS_R_SP);  /* t2 = *(SP + size) */
++	emit_load_delay(ctx);                     /* Load delay slot         */
++	emit(ctx, blez, t2, get_offset(ctx, 1));  /* PC += off(1) if t2 < 0  */
++	emit(ctx, addiu, t2, t2, -1);             /* t2-- (delay slot)       */
++	emit(ctx, sw, t2, ctx->stack_size, MIPS_R_SP);  /* *(SP + size) = t2 */
++
++	/* prog = ary->ptrs[ind] */
++	off = offsetof(struct bpf_array, ptrs);
++	if (off > 0x7fff)
++		return -1;
++	emit(ctx, sll, t1, ind, 2);               /* t1 = ind << 2           */
++	emit(ctx, addu, t1, t1, ary);             /* t1 += ary               */
++	emit(ctx, lw, t2, off, t1);               /* t2 = *(t1 + off)        */
++	emit_load_delay(ctx);                     /* Load delay slot         */
++
++	/* if (prog == 0) goto out */
++	emit(ctx, beqz, t2, get_offset(ctx, 1));  /* PC += off(1) if t2 == 0 */
++	emit(ctx, nop);                           /* Delay slot              */
++
++	/* func = prog->bpf_func + 8 (prologue skip offset) */
++	off = offsetof(struct bpf_prog, bpf_func);
++	if (off > 0x7fff)
++		return -1;
++	emit(ctx, lw, t1, off, t2);                /* t1 = *(t2 + off)       */
++	emit_load_delay(ctx);                      /* Load delay slot        */
++	emit(ctx, addiu, t1, t1, JIT_TCALL_SKIP);  /* t1 += skip (8 or 12)   */
++
++	/* goto func */
++	build_epilogue(ctx, t1);
++	return 0;
++}
++
++/*
++ * Stack frame layout for a JITed program (stack grows down).
++ *
++ * Higher address  : Caller's stack frame       :
++ *                 :----------------------------:
++ *                 : 64-bit eBPF args r3-r5     :
++ *                 :----------------------------:
++ *                 : Reserved / tail call count :
++ *                 +============================+  <--- MIPS sp before call
++ *                 | Callee-saved registers,    |
++ *                 | including RA and FP        |
++ *                 +----------------------------+  <--- eBPF FP (MIPS zero,fp)
++ *                 | Local eBPF variables       |
++ *                 | allocated by program       |
++ *                 +----------------------------+
++ *                 | Reserved for caller-saved  |
++ *                 | registers                  |
++ *                 +----------------------------+
++ *                 | Reserved for 64-bit eBPF   |
++ *                 | args r3-r5 & args passed   |
++ *                 | on stack in kernel calls   |
++ * Lower address   +============================+  <--- MIPS sp
++ */
++
++/* Build program prologue to set up the stack and registers */
++void build_prologue(struct jit_context *ctx)
++{
++	const u8 *r1 = bpf2mips32[BPF_REG_1];
++	const u8 *fp = bpf2mips32[BPF_REG_FP];
++	int stack, saved, locals, reserved;
++
++	/*
++	 * The first two instructions initialize TCC in the reserved (for us)
++	 * 16-byte area in the parent's stack frame. On a tail call, the
++	 * calling function jumps into the prologue after these instructions.
++	 */
++	emit(ctx, ori, MIPS_R_T9, MIPS_R_ZERO,
++	     min(MAX_TAIL_CALL_CNT + 1, 0xffff));
++	emit(ctx, sw, MIPS_R_T9, 0, MIPS_R_SP);
++
++	/*
++	 * Register eBPF R1 contains the 32-bit context pointer argument.
++	 * A 32-bit argument is always passed in MIPS register a0, regardless
++	 * of CPU endianness. Initialize R1 accordingly and zero-extend.
++	 */
++#ifdef __BIG_ENDIAN
++	emit(ctx, move, lo(r1), MIPS_R_A0);
++#endif
++
++	/* === Entry-point for tail calls === */
++
++	/* Zero-extend the 32-bit argument */
++	emit(ctx, move, hi(r1), MIPS_R_ZERO);
++
++	/* If the eBPF frame pointer was accessed it must be saved */
++	if (ctx->accessed & BIT(BPF_REG_FP))
++		clobber_reg64(ctx, fp);
++
++	/* Compute the stack space needed for callee-saved registers */
++	saved = hweight32(ctx->clobbered & JIT_CALLEE_REGS) * sizeof(u32);
++	saved = ALIGN(saved, MIPS_STACK_ALIGNMENT);
++
++	/* Stack space used by eBPF program local data */
++	locals = ALIGN(ctx->program->aux->stack_depth, MIPS_STACK_ALIGNMENT);
++
++	/*
++	 * If we are emitting function calls, reserve extra stack space for
++	 * caller-saved registers and function arguments passed on the stack.
++	 * The required space is computed automatically during resource
++	 * usage discovery (pass 1).
++	 */
++	reserved = ctx->stack_used;
++
++	/* Allocate the stack frame */
++	stack = ALIGN(saved + locals + reserved, MIPS_STACK_ALIGNMENT);
++	emit(ctx, addiu, MIPS_R_SP, MIPS_R_SP, -stack);
++
++	/* Store callee-saved registers on stack */
++	push_regs(ctx, ctx->clobbered & JIT_CALLEE_REGS, 0, stack - saved);
++
++	/* Initialize the eBPF frame pointer if accessed */
++	if (ctx->accessed & BIT(BPF_REG_FP))
++		emit(ctx, addiu, lo(fp), MIPS_R_SP, stack - saved);
++
++	ctx->saved_size = saved;
++	ctx->stack_size = stack;
++}
++
++/* Build the program epilogue to restore the stack and registers */
++void build_epilogue(struct jit_context *ctx, int dest_reg)
++{
++	/* Restore callee-saved registers from stack */
++	pop_regs(ctx, ctx->clobbered & JIT_CALLEE_REGS, 0,
++		 ctx->stack_size - ctx->saved_size);
++	/*
++	 * A 32-bit return value is always passed in MIPS register v0,
++	 * but on big-endian targets the low part of R0 is mapped to v1.
++	 */
++#ifdef __BIG_ENDIAN
++	emit(ctx, move, MIPS_R_V0, MIPS_R_V1);
++#endif
++
++	/* Jump to the return address and adjust the stack pointer */
++	emit(ctx, jr, dest_reg);
++	emit(ctx, addiu, MIPS_R_SP, MIPS_R_SP, ctx->stack_size);
++}
++
++/* Build one eBPF instruction */
++int build_insn(const struct bpf_insn *insn, struct jit_context *ctx)
++{
++	const u8 *dst = bpf2mips32[insn->dst_reg];
++	const u8 *src = bpf2mips32[insn->src_reg];
++	const u8 *tmp = bpf2mips32[JIT_REG_TMP];
++	u8 code = insn->code;
++	s16 off = insn->off;
++	s32 imm = insn->imm;
++	s32 val, rel;
++	u8 alu, jmp;
++
++	switch (code) {
++	/* ALU operations */
++	/* dst = imm */
++	case BPF_ALU | BPF_MOV | BPF_K:
++		emit_mov_i(ctx, lo(dst), imm);
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = src */
++	case BPF_ALU | BPF_MOV | BPF_X:
++		if (imm == 1) {
++			/* Special mov32 for zext */
++			emit_mov_i(ctx, hi(dst), 0);
++		} else {
++			emit_mov_r(ctx, lo(dst), lo(src));
++			emit_zext_ver(ctx, dst);
++		}
++		break;
++	/* dst = -dst */
++	case BPF_ALU | BPF_NEG:
++		emit_alu_i(ctx, lo(dst), 0, BPF_NEG);
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = dst & imm */
++	/* dst = dst | imm */
++	/* dst = dst ^ imm */
++	/* dst = dst << imm */
++	/* dst = dst >> imm */
++	/* dst = dst >> imm (arithmetic) */
++	/* dst = dst + imm */
++	/* dst = dst - imm */
++	/* dst = dst * imm */
++	/* dst = dst / imm */
++	/* dst = dst % imm */
++	case BPF_ALU | BPF_OR | BPF_K:
++	case BPF_ALU | BPF_AND | BPF_K:
++	case BPF_ALU | BPF_XOR | BPF_K:
++	case BPF_ALU | BPF_LSH | BPF_K:
++	case BPF_ALU | BPF_RSH | BPF_K:
++	case BPF_ALU | BPF_ARSH | BPF_K:
++	case BPF_ALU | BPF_ADD | BPF_K:
++	case BPF_ALU | BPF_SUB | BPF_K:
++	case BPF_ALU | BPF_MUL | BPF_K:
++	case BPF_ALU | BPF_DIV | BPF_K:
++	case BPF_ALU | BPF_MOD | BPF_K:
++		if (!valid_alu_i(BPF_OP(code), imm)) {
++			emit_mov_i(ctx, MIPS_R_T6, imm);
++			emit_alu_r(ctx, lo(dst), MIPS_R_T6, BPF_OP(code));
++		} else if (rewrite_alu_i(BPF_OP(code), imm, &alu, &val)) {
++			emit_alu_i(ctx, lo(dst), val, alu);
++		}
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = dst & src */
++	/* dst = dst | src */
++	/* dst = dst ^ src */
++	/* dst = dst << src */
++	/* dst = dst >> src */
++	/* dst = dst >> src (arithmetic) */
++	/* dst = dst + src */
++	/* dst = dst - src */
++	/* dst = dst * src */
++	/* dst = dst / src */
++	/* dst = dst % src */
++	case BPF_ALU | BPF_AND | BPF_X:
++	case BPF_ALU | BPF_OR | BPF_X:
++	case BPF_ALU | BPF_XOR | BPF_X:
++	case BPF_ALU | BPF_LSH | BPF_X:
++	case BPF_ALU | BPF_RSH | BPF_X:
++	case BPF_ALU | BPF_ARSH | BPF_X:
++	case BPF_ALU | BPF_ADD | BPF_X:
++	case BPF_ALU | BPF_SUB | BPF_X:
++	case BPF_ALU | BPF_MUL | BPF_X:
++	case BPF_ALU | BPF_DIV | BPF_X:
++	case BPF_ALU | BPF_MOD | BPF_X:
++		emit_alu_r(ctx, lo(dst), lo(src), BPF_OP(code));
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = imm (64-bit) */
++	case BPF_ALU64 | BPF_MOV | BPF_K:
++		emit_mov_se_i64(ctx, dst, imm);
++		break;
++	/* dst = src (64-bit) */
++	case BPF_ALU64 | BPF_MOV | BPF_X:
++		emit_mov_r(ctx, lo(dst), lo(src));
++		emit_mov_r(ctx, hi(dst), hi(src));
++		break;
++	/* dst = -dst (64-bit) */
++	case BPF_ALU64 | BPF_NEG:
++		emit_neg_i64(ctx, dst);
++		break;
++	/* dst = dst & imm (64-bit) */
++	case BPF_ALU64 | BPF_AND | BPF_K:
++		emit_alu_i64(ctx, dst, imm, BPF_OP(code));
++		break;
++	/* dst = dst | imm (64-bit) */
++	/* dst = dst ^ imm (64-bit) */
++	/* dst = dst + imm (64-bit) */
++	/* dst = dst - imm (64-bit) */
++	case BPF_ALU64 | BPF_OR | BPF_K:
++	case BPF_ALU64 | BPF_XOR | BPF_K:
++	case BPF_ALU64 | BPF_ADD | BPF_K:
++	case BPF_ALU64 | BPF_SUB | BPF_K:
++		if (imm)
++			emit_alu_i64(ctx, dst, imm, BPF_OP(code));
++		break;
++	/* dst = dst << imm (64-bit) */
++	/* dst = dst >> imm (64-bit) */
++	/* dst = dst >> imm (64-bit, arithmetic) */
++	case BPF_ALU64 | BPF_LSH | BPF_K:
++	case BPF_ALU64 | BPF_RSH | BPF_K:
++	case BPF_ALU64 | BPF_ARSH | BPF_K:
++		if (imm)
++			emit_shift_i64(ctx, dst, imm, BPF_OP(code));
++		break;
++	/* dst = dst * imm (64-bit) */
++	case BPF_ALU64 | BPF_MUL | BPF_K:
++		emit_mul_i64(ctx, dst, imm);
++		break;
++	/* dst = dst / imm (64-bit) */
++	/* dst = dst % imm (64-bit) */
++	case BPF_ALU64 | BPF_DIV | BPF_K:
++	case BPF_ALU64 | BPF_MOD | BPF_K:
++		/*
++		 * Sign-extend the immediate value into a temporary register,
++		 * and then do the operation on this register.
++		 */
++		emit_mov_se_i64(ctx, tmp, imm);
++		emit_divmod_r64(ctx, dst, tmp, BPF_OP(code));
++		break;
++	/* dst = dst & src (64-bit) */
++	/* dst = dst | src (64-bit) */
++	/* dst = dst ^ src (64-bit) */
++	/* dst = dst + src (64-bit) */
++	/* dst = dst - src (64-bit) */
++	case BPF_ALU64 | BPF_AND | BPF_X:
++	case BPF_ALU64 | BPF_OR | BPF_X:
++	case BPF_ALU64 | BPF_XOR | BPF_X:
++	case BPF_ALU64 | BPF_ADD | BPF_X:
++	case BPF_ALU64 | BPF_SUB | BPF_X:
++		emit_alu_r64(ctx, dst, src, BPF_OP(code));
++		break;
++	/* dst = dst << src (64-bit) */
++	/* dst = dst >> src (64-bit) */
++	/* dst = dst >> src (64-bit, arithmetic) */
++	case BPF_ALU64 | BPF_LSH | BPF_X:
++	case BPF_ALU64 | BPF_RSH | BPF_X:
++	case BPF_ALU64 | BPF_ARSH | BPF_X:
++		emit_shift_r64(ctx, dst, lo(src), BPF_OP(code));
++		break;
++	/* dst = dst * src (64-bit) */
++	case BPF_ALU64 | BPF_MUL | BPF_X:
++		emit_mul_r64(ctx, dst, src);
++		break;
++	/* dst = dst / src (64-bit) */
++	/* dst = dst % src (64-bit) */
++	case BPF_ALU64 | BPF_DIV | BPF_X:
++	case BPF_ALU64 | BPF_MOD | BPF_X:
++		emit_divmod_r64(ctx, dst, src, BPF_OP(code));
++		break;
++	/* dst = htole(dst) */
++	/* dst = htobe(dst) */
++	case BPF_ALU | BPF_END | BPF_FROM_LE:
++	case BPF_ALU | BPF_END | BPF_FROM_BE:
++		if (BPF_SRC(code) ==
++#ifdef __BIG_ENDIAN
++		    BPF_FROM_LE
++#else
++		    BPF_FROM_BE
++#endif
++		    )
++			emit_bswap_r64(ctx, dst, imm);
++		else
++			emit_trunc_r64(ctx, dst, imm);
++		break;
++	/* dst = imm64 */
++	case BPF_LD | BPF_IMM | BPF_DW:
++		emit_mov_i(ctx, lo(dst), imm);
++		emit_mov_i(ctx, hi(dst), insn[1].imm);
++		return 1;
++	/* LDX: dst = *(size *)(src + off) */
++	case BPF_LDX | BPF_MEM | BPF_W:
++	case BPF_LDX | BPF_MEM | BPF_H:
++	case BPF_LDX | BPF_MEM | BPF_B:
++	case BPF_LDX | BPF_MEM | BPF_DW:
++		emit_ldx(ctx, dst, lo(src), off, BPF_SIZE(code));
++		break;
++	/* ST: *(size *)(dst + off) = imm */
++	case BPF_ST | BPF_MEM | BPF_W:
++	case BPF_ST | BPF_MEM | BPF_H:
++	case BPF_ST | BPF_MEM | BPF_B:
++	case BPF_ST | BPF_MEM | BPF_DW:
++		switch (BPF_SIZE(code)) {
++		case BPF_DW:
++			/* Sign-extend immediate value into temporary reg */
++			emit_mov_se_i64(ctx, tmp, imm);
++			break;
++		case BPF_W:
++		case BPF_H:
++		case BPF_B:
++			emit_mov_i(ctx, lo(tmp), imm);
++			break;
++		}
++		emit_stx(ctx, lo(dst), tmp, off, BPF_SIZE(code));
++		break;
++	/* STX: *(size *)(dst + off) = src */
++	case BPF_STX | BPF_MEM | BPF_W:
++	case BPF_STX | BPF_MEM | BPF_H:
++	case BPF_STX | BPF_MEM | BPF_B:
++	case BPF_STX | BPF_MEM | BPF_DW:
++		emit_stx(ctx, lo(dst), src, off, BPF_SIZE(code));
++		break;
++	/* Speculation barrier */
++	case BPF_ST | BPF_NOSPEC:
++		break;
++	/* Atomics */
++	case BPF_STX | BPF_XADD | BPF_W:
++		switch (imm) {
++		case BPF_ADD:
++		case BPF_AND:
++		case BPF_OR:
++		case BPF_XOR:
++			if (cpu_has_llsc)
++				emit_atomic_r(ctx, lo(dst), lo(src), off, imm);
++			else /* Non-ll/sc fallback */
++				emit_atomic_r32(ctx, lo(dst), lo(src),
++						off, imm);
++			break;
++		default:
++			goto notyet;
++		}
++		break;
++	/* Atomics (64-bit) */
++	case BPF_STX | BPF_XADD | BPF_DW:
++		switch (imm) {
++		case BPF_ADD:
++		case BPF_AND:
++		case BPF_OR:
++		case BPF_XOR:
++			emit_atomic_r64(ctx, lo(dst), src, off, imm);
++			break;
++		default:
++			goto notyet;
++		}
++		break;
++	/* PC += off if dst == src */
++	/* PC += off if dst != src */
++	/* PC += off if dst & src */
++	/* PC += off if dst > src */
++	/* PC += off if dst >= src */
++	/* PC += off if dst < src */
++	/* PC += off if dst <= src */
++	/* PC += off if dst > src (signed) */
++	/* PC += off if dst >= src (signed) */
++	/* PC += off if dst < src (signed) */
++	/* PC += off if dst <= src (signed) */
++	case BPF_JMP32 | BPF_JEQ | BPF_X:
++	case BPF_JMP32 | BPF_JNE | BPF_X:
++	case BPF_JMP32 | BPF_JSET | 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:
++		if (off == 0)
++			break;
++		setup_jmp_r(ctx, dst == src, BPF_OP(code), off, &jmp, &rel);
++		emit_jmp_r(ctx, lo(dst), lo(src), rel, jmp);
++		if (finish_jmp(ctx, jmp, off) < 0)
++			goto toofar;
++		break;
++	/* PC += off if dst == imm */
++	/* PC += off if dst != imm */
++	/* PC += off if dst & imm */
++	/* PC += off if dst > imm */
++	/* PC += off if dst >= imm */
++	/* PC += off if dst < imm */
++	/* PC += off if dst <= imm */
++	/* PC += off if dst > imm (signed) */
++	/* PC += off if dst >= imm (signed) */
++	/* PC += off if dst < imm (signed) */
++	/* PC += off if dst <= imm (signed) */
++	case BPF_JMP32 | BPF_JEQ | BPF_K:
++	case BPF_JMP32 | BPF_JNE | BPF_K:
++	case BPF_JMP32 | BPF_JSET | 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:
++		if (off == 0)
++			break;
++		setup_jmp_i(ctx, imm, 32, BPF_OP(code), off, &jmp, &rel);
++		if (valid_jmp_i(jmp, imm)) {
++			emit_jmp_i(ctx, lo(dst), imm, rel, jmp);
++		} else {
++			/* Move large immediate to register */
++			emit_mov_i(ctx, MIPS_R_T6, imm);
++			emit_jmp_r(ctx, lo(dst), MIPS_R_T6, rel, jmp);
++		}
++		if (finish_jmp(ctx, jmp, off) < 0)
++			goto toofar;
++		break;
++	/* PC += off if dst == src */
++	/* PC += off if dst != src */
++	/* PC += off if dst & src */
++	/* PC += off if dst > src */
++	/* PC += off if dst >= src */
++	/* PC += off if dst < src */
++	/* PC += off if dst <= src */
++	/* PC += off if dst > src (signed) */
++	/* PC += off if dst >= src (signed) */
++	/* PC += off if dst < src (signed) */
++	/* PC += off if dst <= src (signed) */
++	case BPF_JMP | BPF_JEQ | BPF_X:
++	case BPF_JMP | BPF_JNE | BPF_X:
++	case BPF_JMP | BPF_JSET | 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:
++		if (off == 0)
++			break;
++		setup_jmp_r(ctx, dst == src, BPF_OP(code), off, &jmp, &rel);
++		emit_jmp_r64(ctx, dst, src, rel, jmp);
++		if (finish_jmp(ctx, jmp, off) < 0)
++			goto toofar;
++		break;
++	/* PC += off if dst == imm */
++	/* PC += off if dst != imm */
++	/* PC += off if dst & imm */
++	/* PC += off if dst > imm */
++	/* PC += off if dst >= imm */
++	/* PC += off if dst < imm */
++	/* PC += off if dst <= imm */
++	/* PC += off if dst > imm (signed) */
++	/* PC += off if dst >= imm (signed) */
++	/* PC += off if dst < imm (signed) */
++	/* PC += off if dst <= imm (signed) */
++	case BPF_JMP | BPF_JEQ | BPF_K:
++	case BPF_JMP | BPF_JNE | BPF_K:
++	case BPF_JMP | BPF_JSET | 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:
++		if (off == 0)
++			break;
++		setup_jmp_i(ctx, imm, 64, BPF_OP(code), off, &jmp, &rel);
++		emit_jmp_i64(ctx, dst, imm, rel, jmp);
++		if (finish_jmp(ctx, jmp, off) < 0)
++			goto toofar;
++		break;
++	/* PC += off */
++	case BPF_JMP | BPF_JA:
++		if (off == 0)
++			break;
++		if (emit_ja(ctx, off) < 0)
++			goto toofar;
++		break;
++	/* Tail call */
++	case BPF_JMP | BPF_TAIL_CALL:
++		if (emit_tail_call(ctx) < 0)
++			goto invalid;
++		break;
++	/* Function call */
++	case BPF_JMP | BPF_CALL:
++		if (emit_call(ctx, insn) < 0)
++			goto invalid;
++		break;
++	/* Function return */
++	case BPF_JMP | BPF_EXIT:
++		/*
++		 * Optimization: when last instruction is EXIT
++		 * simply continue to epilogue.
++		 */
++		if (ctx->bpf_index == ctx->program->len - 1)
++			break;
++		if (emit_exit(ctx) < 0)
++			goto toofar;
++		break;
++
++	default:
++invalid:
++		pr_err_once("unknown opcode %02x\n", code);
++		return -EINVAL;
++notyet:
++		pr_info_once("*** NOT YET: opcode %02x ***\n", code);
++		return -EFAULT;
++toofar:
++		pr_info_once("*** TOO FAR: jump at %u opcode %02x ***\n",
++			     ctx->bpf_index, code);
++		return -E2BIG;
++	}
++	return 0;
++}
diff --git a/target/linux/generic/backport-5.10/050-v5.16-03-mips-bpf-Add-new-eBPF-JIT-for-64-bit-MIPS.patch b/target/linux/generic/backport-5.10/050-v5.16-03-mips-bpf-Add-new-eBPF-JIT-for-64-bit-MIPS.patch
new file mode 100644
index 0000000000..38b46c0b76
--- /dev/null
+++ b/target/linux/generic/backport-5.10/050-v5.16-03-mips-bpf-Add-new-eBPF-JIT-for-64-bit-MIPS.patch
@@ -0,0 +1,1005 @@
+From: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+Date: Tue, 5 Oct 2021 18:54:05 +0200
+Subject: [PATCH] mips: bpf: Add new eBPF JIT for 64-bit MIPS
+
+This is an implementation on of an eBPF JIT for 64-bit MIPS III-V and
+MIPS64r1-r6. It uses the same framework introduced by the 32-bit JIT.
+
+Signed-off-by: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+---
+ create mode 100644 arch/mips/net/bpf_jit_comp64.c
+
+--- /dev/null
++++ b/arch/mips/net/bpf_jit_comp64.c
+@@ -0,0 +1,991 @@
++// SPDX-License-Identifier: GPL-2.0-only
++/*
++ * Just-In-Time compiler for eBPF bytecode on MIPS.
++ * Implementation of JIT functions for 64-bit CPUs.
++ *
++ * Copyright (c) 2021 Anyfi Networks AB.
++ * Author: Johan Almbladh <johan.almbladh at gmail.com>
++ *
++ * Based on code and ideas from
++ * Copyright (c) 2017 Cavium, Inc.
++ * Copyright (c) 2017 Shubham Bansal <illusionist.neo at gmail.com>
++ * Copyright (c) 2011 Mircea Gherzan <mgherzan at gmail.com>
++ */
++
++#include <linux/errno.h>
++#include <linux/filter.h>
++#include <linux/bpf.h>
++#include <asm/cpu-features.h>
++#include <asm/isa-rev.h>
++#include <asm/uasm.h>
++
++#include "bpf_jit_comp.h"
++
++/* MIPS t0-t3 are not available in the n64 ABI */
++#undef MIPS_R_T0
++#undef MIPS_R_T1
++#undef MIPS_R_T2
++#undef MIPS_R_T3
++
++/* Stack is 16-byte aligned in n64 ABI */
++#define MIPS_STACK_ALIGNMENT 16
++
++/* Extra 64-bit eBPF registers used by JIT */
++#define JIT_REG_TC (MAX_BPF_JIT_REG + 0)
++#define JIT_REG_ZX (MAX_BPF_JIT_REG + 1)
++
++/* Number of prologue bytes to skip when doing a tail call */
++#define JIT_TCALL_SKIP 4
++
++/* Callee-saved CPU registers that the JIT must preserve */
++#define JIT_CALLEE_REGS   \
++	(BIT(MIPS_R_S0) | \
++	 BIT(MIPS_R_S1) | \
++	 BIT(MIPS_R_S2) | \
++	 BIT(MIPS_R_S3) | \
++	 BIT(MIPS_R_S4) | \
++	 BIT(MIPS_R_S5) | \
++	 BIT(MIPS_R_S6) | \
++	 BIT(MIPS_R_S7) | \
++	 BIT(MIPS_R_GP) | \
++	 BIT(MIPS_R_FP) | \
++	 BIT(MIPS_R_RA))
++
++/* Caller-saved CPU registers available for JIT use */
++#define JIT_CALLER_REGS	  \
++	(BIT(MIPS_R_A5) | \
++	 BIT(MIPS_R_A6) | \
++	 BIT(MIPS_R_A7))
++/*
++ * Mapping of 64-bit eBPF registers to 64-bit native MIPS registers.
++ * MIPS registers t4 - t7 may be used by the JIT as temporary registers.
++ * MIPS registers t8 - t9 are reserved for single-register common functions.
++ */
++static const u8 bpf2mips64[] = {
++	/* Return value from in-kernel function, and exit value from eBPF */
++	[BPF_REG_0] = MIPS_R_V0,
++	/* Arguments from eBPF program to in-kernel function */
++	[BPF_REG_1] = MIPS_R_A0,
++	[BPF_REG_2] = MIPS_R_A1,
++	[BPF_REG_3] = MIPS_R_A2,
++	[BPF_REG_4] = MIPS_R_A3,
++	[BPF_REG_5] = MIPS_R_A4,
++	/* Callee-saved registers that in-kernel function will preserve */
++	[BPF_REG_6] = MIPS_R_S0,
++	[BPF_REG_7] = MIPS_R_S1,
++	[BPF_REG_8] = MIPS_R_S2,
++	[BPF_REG_9] = MIPS_R_S3,
++	/* Read-only frame pointer to access the eBPF stack */
++	[BPF_REG_FP] = MIPS_R_FP,
++	/* Temporary register for blinding constants */
++	[BPF_REG_AX] = MIPS_R_AT,
++	/* Tail call count register, caller-saved */
++	[JIT_REG_TC] = MIPS_R_A5,
++	/* Constant for register zero-extension */
++	[JIT_REG_ZX] = MIPS_R_V1,
++};
++
++/*
++ * MIPS 32-bit operations on 64-bit registers generate a sign-extended
++ * result. However, the eBPF ISA mandates zero-extension, so we rely on the
++ * verifier to add that for us (emit_zext_ver). In addition, ALU arithmetic
++ * operations, right shift and byte swap require properly sign-extended
++ * operands or the result is unpredictable. We emit explicit sign-extensions
++ * in those cases.
++ */
++
++/* Sign extension */
++static void emit_sext(struct jit_context *ctx, u8 dst, u8 src)
++{
++	emit(ctx, sll, dst, src, 0);
++	clobber_reg(ctx, dst);
++}
++
++/* Zero extension */
++static void emit_zext(struct jit_context *ctx, u8 dst)
++{
++	if (cpu_has_mips64r2 || cpu_has_mips64r6) {
++		emit(ctx, dinsu, dst, MIPS_R_ZERO, 32, 32);
++	} else {
++		emit(ctx, and, dst, dst, bpf2mips64[JIT_REG_ZX]);
++		access_reg(ctx, JIT_REG_ZX); /* We need the ZX register */
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* Zero extension, if verifier does not do it for us  */
++static void emit_zext_ver(struct jit_context *ctx, u8 dst)
++{
++	if (!ctx->program->aux->verifier_zext)
++		emit_zext(ctx, dst);
++}
++
++/* dst = imm (64-bit) */
++static void emit_mov_i64(struct jit_context *ctx, u8 dst, u64 imm64)
++{
++	if (imm64 >= 0xffffffffffff8000ULL || imm64 < 0x8000ULL) {
++		emit(ctx, daddiu, dst, MIPS_R_ZERO, (s16)imm64);
++	} else if (imm64 >= 0xffffffff80000000ULL ||
++		   (imm64 < 0x80000000 && imm64 > 0xffff)) {
++		emit(ctx, lui, dst, (s16)(imm64 >> 16));
++		emit(ctx, ori, dst, dst, (u16)imm64 & 0xffff);
++	} else {
++		u8 acc = MIPS_R_ZERO;
++		int k;
++
++		for (k = 0; k < 4; k++) {
++			u16 half = imm64 >> (48 - 16 * k);
++
++			if (acc == dst)
++				emit(ctx, dsll, dst, dst, 16);
++
++			if (half) {
++				emit(ctx, ori, dst, acc, half);
++				acc = dst;
++			}
++		}
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* ALU immediate operation (64-bit) */
++static void emit_alu_i64(struct jit_context *ctx, u8 dst, s32 imm, u8 op)
++{
++	switch (BPF_OP(op)) {
++	/* dst = dst | imm */
++	case BPF_OR:
++		emit(ctx, ori, dst, dst, (u16)imm);
++		break;
++	/* dst = dst ^ imm */
++	case BPF_XOR:
++		emit(ctx, xori, dst, dst, (u16)imm);
++		break;
++	/* dst = -dst */
++	case BPF_NEG:
++		emit(ctx, dsubu, dst, MIPS_R_ZERO, dst);
++		break;
++	/* dst = dst << imm */
++	case BPF_LSH:
++		emit(ctx, dsll_safe, dst, dst, imm);
++		break;
++	/* dst = dst >> imm */
++	case BPF_RSH:
++		emit(ctx, dsrl_safe, dst, dst, imm);
++		break;
++	/* dst = dst >> imm (arithmetic) */
++	case BPF_ARSH:
++		emit(ctx, dsra_safe, dst, dst, imm);
++		break;
++	/* dst = dst + imm */
++	case BPF_ADD:
++		emit(ctx, daddiu, dst, dst, imm);
++		break;
++	/* dst = dst - imm */
++	case BPF_SUB:
++		emit(ctx, daddiu, dst, dst, -imm);
++		break;
++	default:
++		/* Width-generic operations */
++		emit_alu_i(ctx, dst, imm, op);
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* ALU register operation (64-bit) */
++static void emit_alu_r64(struct jit_context *ctx, u8 dst, u8 src, u8 op)
++{
++	switch (BPF_OP(op)) {
++	/* dst = dst << src */
++	case BPF_LSH:
++		emit(ctx, dsllv, dst, dst, src);
++		break;
++	/* dst = dst >> src */
++	case BPF_RSH:
++		emit(ctx, dsrlv, dst, dst, src);
++		break;
++	/* dst = dst >> src (arithmetic) */
++	case BPF_ARSH:
++		emit(ctx, dsrav, dst, dst, src);
++		break;
++	/* dst = dst + src */
++	case BPF_ADD:
++		emit(ctx, daddu, dst, dst, src);
++		break;
++	/* dst = dst - src */
++	case BPF_SUB:
++		emit(ctx, dsubu, dst, dst, src);
++		break;
++	/* dst = dst * src */
++	case BPF_MUL:
++		if (cpu_has_mips64r6) {
++			emit(ctx, dmulu, dst, dst, src);
++		} else {
++			emit(ctx, dmultu, dst, src);
++			emit(ctx, mflo, dst);
++		}
++		break;
++	/* dst = dst / src */
++	case BPF_DIV:
++		if (cpu_has_mips64r6) {
++			emit(ctx, ddivu_r6, dst, dst, src);
++		} else {
++			emit(ctx, ddivu, dst, src);
++			emit(ctx, mflo, dst);
++		}
++		break;
++	/* dst = dst % src */
++	case BPF_MOD:
++		if (cpu_has_mips64r6) {
++			emit(ctx, dmodu, dst, dst, src);
++		} else {
++			emit(ctx, ddivu, dst, src);
++			emit(ctx, mfhi, dst);
++		}
++		break;
++	default:
++		/* Width-generic operations */
++		emit_alu_r(ctx, dst, src, op);
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* Swap sub words in a register double word */
++static void emit_swap_r64(struct jit_context *ctx, u8 dst, u8 mask, u32 bits)
++{
++	u8 tmp = MIPS_R_T9;
++
++	emit(ctx, and, tmp, dst, mask);  /* tmp = dst & mask  */
++	emit(ctx, dsll, tmp, tmp, bits); /* tmp = tmp << bits */
++	emit(ctx, dsrl, dst, dst, bits); /* dst = dst >> bits */
++	emit(ctx, and, dst, dst, mask);  /* dst = dst & mask  */
++	emit(ctx, or, dst, dst, tmp);    /* dst = dst | tmp   */
++}
++
++/* Swap bytes and truncate a register double word, word or half word */
++static void emit_bswap_r64(struct jit_context *ctx, u8 dst, u32 width)
++{
++	switch (width) {
++	/* Swap bytes in a double word */
++	case 64:
++		if (cpu_has_mips64r2 || cpu_has_mips64r6) {
++			emit(ctx, dsbh, dst, dst);
++			emit(ctx, dshd, dst, dst);
++		} else {
++			u8 t1 = MIPS_R_T6;
++			u8 t2 = MIPS_R_T7;
++
++			emit(ctx, dsll32, t2, dst, 0);  /* t2 = dst << 32    */
++			emit(ctx, dsrl32, dst, dst, 0); /* dst = dst >> 32   */
++			emit(ctx, or, dst, dst, t2);    /* dst = dst | t2    */
++
++			emit(ctx, ori, t2, MIPS_R_ZERO, 0xffff);
++			emit(ctx, dsll32, t1, t2, 0);   /* t1 = t2 << 32     */
++			emit(ctx, or, t1, t1, t2);      /* t1 = t1 | t2      */
++			emit_swap_r64(ctx, dst, t1, 16);/* dst = swap16(dst) */
++
++			emit(ctx, lui, t2, 0xff);       /* t2 = 0x00ff0000   */
++			emit(ctx, ori, t2, t2, 0xff);   /* t2 = t2 | 0x00ff  */
++			emit(ctx, dsll32, t1, t2, 0);   /* t1 = t2 << 32     */
++			emit(ctx, or, t1, t1, t2);      /* t1 = t1 | t2      */
++			emit_swap_r64(ctx, dst, t1, 8); /* dst = swap8(dst)  */
++		}
++		break;
++	/* Swap bytes in a half word */
++	/* Swap bytes in a word */
++	case 32:
++	case 16:
++		emit_sext(ctx, dst, dst);
++		emit_bswap_r(ctx, dst, width);
++		if (cpu_has_mips64r2 || cpu_has_mips64r6)
++			emit_zext(ctx, dst);
++		break;
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* Truncate a register double word, word or half word */
++static void emit_trunc_r64(struct jit_context *ctx, u8 dst, u32 width)
++{
++	switch (width) {
++	case 64:
++		break;
++	/* Zero-extend a word */
++	case 32:
++		emit_zext(ctx, dst);
++		break;
++	/* Zero-extend a half word */
++	case 16:
++		emit(ctx, andi, dst, dst, 0xffff);
++		break;
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* Load operation: dst = *(size*)(src + off) */
++static void emit_ldx(struct jit_context *ctx, u8 dst, u8 src, s16 off, u8 size)
++{
++	switch (size) {
++	/* Load a byte */
++	case BPF_B:
++		emit(ctx, lbu, dst, off, src);
++		break;
++	/* Load a half word */
++	case BPF_H:
++		emit(ctx, lhu, dst, off, src);
++		break;
++	/* Load a word */
++	case BPF_W:
++		emit(ctx, lwu, dst, off, src);
++		break;
++	/* Load a double word */
++	case BPF_DW:
++		emit(ctx, ld, dst, off, src);
++		break;
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* Store operation: *(size *)(dst + off) = src */
++static void emit_stx(struct jit_context *ctx, u8 dst, u8 src, s16 off, u8 size)
++{
++	switch (size) {
++	/* Store a byte */
++	case BPF_B:
++		emit(ctx, sb, src, off, dst);
++		break;
++	/* Store a half word */
++	case BPF_H:
++		emit(ctx, sh, src, off, dst);
++		break;
++	/* Store a word */
++	case BPF_W:
++		emit(ctx, sw, src, off, dst);
++		break;
++	/* Store a double word */
++	case BPF_DW:
++		emit(ctx, sd, src, off, dst);
++		break;
++	}
++}
++
++/* Atomic read-modify-write */
++static void emit_atomic_r64(struct jit_context *ctx,
++			    u8 dst, u8 src, s16 off, u8 code)
++{
++	u8 t1 = MIPS_R_T6;
++	u8 t2 = MIPS_R_T7;
++
++	emit(ctx, lld, t1, off, dst);
++	switch (code) {
++	case BPF_ADD:
++		emit(ctx, daddu, t2, t1, src);
++		break;
++	case BPF_AND:
++		emit(ctx, and, t2, t1, src);
++		break;
++	case BPF_OR:
++		emit(ctx, or, t2, t1, src);
++		break;
++	case BPF_XOR:
++		emit(ctx, xor, t2, t1, src);
++		break;
++	}
++	emit(ctx, scd, t2, off, dst);
++	emit(ctx, beqz, t2, -16);
++	emit(ctx, nop); /* Delay slot */
++}
++
++/* Function call */
++static int emit_call(struct jit_context *ctx, const struct bpf_insn *insn)
++{
++	u8 zx = bpf2mips64[JIT_REG_ZX];
++	u8 tmp = MIPS_R_T6;
++	bool fixed;
++	u64 addr;
++
++	/* Decode the call address */
++	if (bpf_jit_get_func_addr(ctx->program, insn, false,
++				  &addr, &fixed) < 0)
++		return -1;
++	if (!fixed)
++		return -1;
++
++	/* Push caller-saved registers on stack */
++	push_regs(ctx, ctx->clobbered & JIT_CALLER_REGS, 0, 0);
++
++	/* Emit function call */
++	emit_mov_i64(ctx, tmp, addr);
++	emit(ctx, jalr, MIPS_R_RA, tmp);
++	emit(ctx, nop); /* Delay slot */
++
++	/* Restore caller-saved registers */
++	pop_regs(ctx, ctx->clobbered & JIT_CALLER_REGS, 0, 0);
++
++	/* Re-initialize the JIT zero-extension register if accessed */
++	if (ctx->accessed & BIT(JIT_REG_ZX)) {
++		emit(ctx, daddiu, zx, MIPS_R_ZERO, -1);
++		emit(ctx, dsrl32, zx, zx, 0);
++	}
++
++	clobber_reg(ctx, MIPS_R_RA);
++	clobber_reg(ctx, MIPS_R_V0);
++	clobber_reg(ctx, MIPS_R_V1);
++	return 0;
++}
++
++/* Function tail call */
++static int emit_tail_call(struct jit_context *ctx)
++{
++	u8 ary = bpf2mips64[BPF_REG_2];
++	u8 ind = bpf2mips64[BPF_REG_3];
++	u8 tcc = bpf2mips64[JIT_REG_TC];
++	u8 tmp = MIPS_R_T6;
++	int off;
++
++	/*
++	 * Tail call:
++	 * eBPF R1 - function argument (context ptr), passed in a0-a1
++	 * eBPF R2 - ptr to object with array of function entry points
++	 * eBPF R3 - array index of function to be called
++	 */
++
++	/* if (ind >= ary->map.max_entries) goto out */
++	off = offsetof(struct bpf_array, map.max_entries);
++	if (off > 0x7fff)
++		return -1;
++	emit(ctx, lwu, tmp, off, ary);            /* tmp = ary->map.max_entrs*/
++	emit(ctx, sltu, tmp, ind, tmp);           /* tmp = ind < t1          */
++	emit(ctx, beqz, tmp, get_offset(ctx, 1)); /* PC += off(1) if tmp == 0*/
++
++	/* if (--TCC < 0) goto out */
++	emit(ctx, daddiu, tcc, tcc, -1);          /* tcc-- (delay slot)      */
++	emit(ctx, bltz, tcc, get_offset(ctx, 1)); /* PC += off(1) if tcc < 0 */
++						  /* (next insn delay slot)  */
++	/* prog = ary->ptrs[ind] */
++	off = offsetof(struct bpf_array, ptrs);
++	if (off > 0x7fff)
++		return -1;
++	emit(ctx, dsll, tmp, ind, 3);             /* tmp = ind << 3          */
++	emit(ctx, daddu, tmp, tmp, ary);          /* tmp += ary              */
++	emit(ctx, ld, tmp, off, tmp);             /* tmp = *(tmp + off)      */
++
++	/* if (prog == 0) goto out */
++	emit(ctx, beqz, tmp, get_offset(ctx, 1)); /* PC += off(1) if tmp == 0*/
++	emit(ctx, nop);                           /* Delay slot              */
++
++	/* func = prog->bpf_func + 8 (prologue skip offset) */
++	off = offsetof(struct bpf_prog, bpf_func);
++	if (off > 0x7fff)
++		return -1;
++	emit(ctx, ld, tmp, off, tmp);                /* tmp = *(tmp + off)   */
++	emit(ctx, daddiu, tmp, tmp, JIT_TCALL_SKIP); /* tmp += skip (4)      */
++
++	/* goto func */
++	build_epilogue(ctx, tmp);
++	access_reg(ctx, JIT_REG_TC);
++	return 0;
++}
++
++/*
++ * Stack frame layout for a JITed program (stack grows down).
++ *
++ * Higher address  : Previous stack frame      :
++ *                 +===========================+  <--- MIPS sp before call
++ *                 | Callee-saved registers,   |
++ *                 | including RA and FP       |
++ *                 +---------------------------+  <--- eBPF FP (MIPS fp)
++ *                 | Local eBPF variables      |
++ *                 | allocated by program      |
++ *                 +---------------------------+
++ *                 | Reserved for caller-saved |
++ *                 | registers                 |
++ * Lower address   +===========================+  <--- MIPS sp
++ */
++
++/* Build program prologue to set up the stack and registers */
++void build_prologue(struct jit_context *ctx)
++{
++	u8 fp = bpf2mips64[BPF_REG_FP];
++	u8 tc = bpf2mips64[JIT_REG_TC];
++	u8 zx = bpf2mips64[JIT_REG_ZX];
++	int stack, saved, locals, reserved;
++
++	/*
++	 * The first instruction initializes the tail call count register.
++	 * On a tail call, the calling function jumps into the prologue
++	 * after this instruction.
++	 */
++	emit(ctx, addiu, tc, MIPS_R_ZERO, min(MAX_TAIL_CALL_CNT + 1, 0xffff));
++
++	/* === Entry-point for tail calls === */
++
++	/*
++	 * If the eBPF frame pointer and tail call count registers were
++	 * accessed they must be preserved. Mark them as clobbered here
++	 * to save and restore them on the stack as needed.
++	 */
++	if (ctx->accessed & BIT(BPF_REG_FP))
++		clobber_reg(ctx, fp);
++	if (ctx->accessed & BIT(JIT_REG_TC))
++		clobber_reg(ctx, tc);
++	if (ctx->accessed & BIT(JIT_REG_ZX))
++		clobber_reg(ctx, zx);
++
++	/* Compute the stack space needed for callee-saved registers */
++	saved = hweight32(ctx->clobbered & JIT_CALLEE_REGS) * sizeof(u64);
++	saved = ALIGN(saved, MIPS_STACK_ALIGNMENT);
++
++	/* Stack space used by eBPF program local data */
++	locals = ALIGN(ctx->program->aux->stack_depth, MIPS_STACK_ALIGNMENT);
++
++	/*
++	 * If we are emitting function calls, reserve extra stack space for
++	 * caller-saved registers needed by the JIT. The required space is
++	 * computed automatically during resource usage discovery (pass 1).
++	 */
++	reserved = ctx->stack_used;
++
++	/* Allocate the stack frame */
++	stack = ALIGN(saved + locals + reserved, MIPS_STACK_ALIGNMENT);
++	if (stack)
++		emit(ctx, daddiu, MIPS_R_SP, MIPS_R_SP, -stack);
++
++	/* Store callee-saved registers on stack */
++	push_regs(ctx, ctx->clobbered & JIT_CALLEE_REGS, 0, stack - saved);
++
++	/* Initialize the eBPF frame pointer if accessed */
++	if (ctx->accessed & BIT(BPF_REG_FP))
++		emit(ctx, daddiu, fp, MIPS_R_SP, stack - saved);
++
++	/* Initialize the ePF JIT zero-extension register if accessed */
++	if (ctx->accessed & BIT(JIT_REG_ZX)) {
++		emit(ctx, daddiu, zx, MIPS_R_ZERO, -1);
++		emit(ctx, dsrl32, zx, zx, 0);
++	}
++
++	ctx->saved_size = saved;
++	ctx->stack_size = stack;
++}
++
++/* Build the program epilogue to restore the stack and registers */
++void build_epilogue(struct jit_context *ctx, int dest_reg)
++{
++	/* Restore callee-saved registers from stack */
++	pop_regs(ctx, ctx->clobbered & JIT_CALLEE_REGS, 0,
++		 ctx->stack_size - ctx->saved_size);
++
++	/* Release the stack frame */
++	if (ctx->stack_size)
++		emit(ctx, daddiu, MIPS_R_SP, MIPS_R_SP, ctx->stack_size);
++
++	/* Jump to return address and sign-extend the 32-bit return value */
++	emit(ctx, jr, dest_reg);
++	emit(ctx, sll, MIPS_R_V0, MIPS_R_V0, 0); /* Delay slot */
++}
++
++/* Build one eBPF instruction */
++int build_insn(const struct bpf_insn *insn, struct jit_context *ctx)
++{
++	u8 dst = bpf2mips64[insn->dst_reg];
++	u8 src = bpf2mips64[insn->src_reg];
++	u8 code = insn->code;
++	s16 off = insn->off;
++	s32 imm = insn->imm;
++	s32 val, rel;
++	u8 alu, jmp;
++
++	switch (code) {
++	/* ALU operations */
++	/* dst = imm */
++	case BPF_ALU | BPF_MOV | BPF_K:
++		emit_mov_i(ctx, dst, imm);
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = src */
++	case BPF_ALU | BPF_MOV | BPF_X:
++		if (imm == 1) {
++			/* Special mov32 for zext */
++			emit_zext(ctx, dst);
++		} else {
++			emit_mov_r(ctx, dst, src);
++			emit_zext_ver(ctx, dst);
++		}
++		break;
++	/* dst = -dst */
++	case BPF_ALU | BPF_NEG:
++		emit_sext(ctx, dst, dst);
++		emit_alu_i(ctx, dst, 0, BPF_NEG);
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = dst & imm */
++	/* dst = dst | imm */
++	/* dst = dst ^ imm */
++	/* dst = dst << imm */
++	case BPF_ALU | BPF_OR | BPF_K:
++	case BPF_ALU | BPF_AND | BPF_K:
++	case BPF_ALU | BPF_XOR | BPF_K:
++	case BPF_ALU | BPF_LSH | BPF_K:
++		if (!valid_alu_i(BPF_OP(code), imm)) {
++			emit_mov_i(ctx, MIPS_R_T4, imm);
++			emit_alu_r(ctx, dst, MIPS_R_T4, BPF_OP(code));
++		} else if (rewrite_alu_i(BPF_OP(code), imm, &alu, &val)) {
++			emit_alu_i(ctx, dst, val, alu);
++		}
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = dst >> imm */
++	/* dst = dst >> imm (arithmetic) */
++	/* dst = dst + imm */
++	/* dst = dst - imm */
++	/* dst = dst * imm */
++	/* dst = dst / imm */
++	/* dst = dst % imm */
++	case BPF_ALU | BPF_RSH | BPF_K:
++	case BPF_ALU | BPF_ARSH | BPF_K:
++	case BPF_ALU | BPF_ADD | BPF_K:
++	case BPF_ALU | BPF_SUB | BPF_K:
++	case BPF_ALU | BPF_MUL | BPF_K:
++	case BPF_ALU | BPF_DIV | BPF_K:
++	case BPF_ALU | BPF_MOD | BPF_K:
++		if (!valid_alu_i(BPF_OP(code), imm)) {
++			emit_sext(ctx, dst, dst);
++			emit_mov_i(ctx, MIPS_R_T4, imm);
++			emit_alu_r(ctx, dst, MIPS_R_T4, BPF_OP(code));
++		} else if (rewrite_alu_i(BPF_OP(code), imm, &alu, &val)) {
++			emit_sext(ctx, dst, dst);
++			emit_alu_i(ctx, dst, val, alu);
++		}
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = dst & src */
++	/* dst = dst | src */
++	/* dst = dst ^ src */
++	/* dst = dst << src */
++	case BPF_ALU | BPF_AND | BPF_X:
++	case BPF_ALU | BPF_OR | BPF_X:
++	case BPF_ALU | BPF_XOR | BPF_X:
++	case BPF_ALU | BPF_LSH | BPF_X:
++		emit_alu_r(ctx, dst, src, BPF_OP(code));
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = dst >> src */
++	/* dst = dst >> src (arithmetic) */
++	/* dst = dst + src */
++	/* dst = dst - src */
++	/* dst = dst * src */
++	/* dst = dst / src */
++	/* dst = dst % src */
++	case BPF_ALU | BPF_RSH | BPF_X:
++	case BPF_ALU | BPF_ARSH | BPF_X:
++	case BPF_ALU | BPF_ADD | BPF_X:
++	case BPF_ALU | BPF_SUB | BPF_X:
++	case BPF_ALU | BPF_MUL | BPF_X:
++	case BPF_ALU | BPF_DIV | BPF_X:
++	case BPF_ALU | BPF_MOD | BPF_X:
++		emit_sext(ctx, dst, dst);
++		emit_sext(ctx, MIPS_R_T4, src);
++		emit_alu_r(ctx, dst, MIPS_R_T4, BPF_OP(code));
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = imm (64-bit) */
++	case BPF_ALU64 | BPF_MOV | BPF_K:
++		emit_mov_i(ctx, dst, imm);
++		break;
++	/* dst = src (64-bit) */
++	case BPF_ALU64 | BPF_MOV | BPF_X:
++		emit_mov_r(ctx, dst, src);
++		break;
++	/* dst = -dst (64-bit) */
++	case BPF_ALU64 | BPF_NEG:
++		emit_alu_i64(ctx, dst, 0, BPF_NEG);
++		break;
++	/* dst = dst & imm (64-bit) */
++	/* dst = dst | imm (64-bit) */
++	/* dst = dst ^ imm (64-bit) */
++	/* dst = dst << imm (64-bit) */
++	/* dst = dst >> imm (64-bit) */
++	/* dst = dst >> imm ((64-bit, arithmetic) */
++	/* dst = dst + imm (64-bit) */
++	/* dst = dst - imm (64-bit) */
++	/* dst = dst * imm (64-bit) */
++	/* dst = dst / imm (64-bit) */
++	/* dst = dst % imm (64-bit) */
++	case BPF_ALU64 | BPF_AND | BPF_K:
++	case BPF_ALU64 | BPF_OR | BPF_K:
++	case BPF_ALU64 | BPF_XOR | BPF_K:
++	case BPF_ALU64 | BPF_LSH | BPF_K:
++	case BPF_ALU64 | BPF_RSH | BPF_K:
++	case BPF_ALU64 | BPF_ARSH | BPF_K:
++	case BPF_ALU64 | BPF_ADD | BPF_K:
++	case BPF_ALU64 | BPF_SUB | BPF_K:
++	case BPF_ALU64 | BPF_MUL | BPF_K:
++	case BPF_ALU64 | BPF_DIV | BPF_K:
++	case BPF_ALU64 | BPF_MOD | BPF_K:
++		if (!valid_alu_i(BPF_OP(code), imm)) {
++			emit_mov_i(ctx, MIPS_R_T4, imm);
++			emit_alu_r64(ctx, dst, MIPS_R_T4, BPF_OP(code));
++		} else if (rewrite_alu_i(BPF_OP(code), imm, &alu, &val)) {
++			emit_alu_i64(ctx, dst, val, alu);
++		}
++		break;
++	/* dst = dst & src (64-bit) */
++	/* dst = dst | src (64-bit) */
++	/* dst = dst ^ src (64-bit) */
++	/* dst = dst << src (64-bit) */
++	/* dst = dst >> src (64-bit) */
++	/* dst = dst >> src (64-bit, arithmetic) */
++	/* dst = dst + src (64-bit) */
++	/* dst = dst - src (64-bit) */
++	/* dst = dst * src (64-bit) */
++	/* dst = dst / src (64-bit) */
++	/* dst = dst % src (64-bit) */
++	case BPF_ALU64 | BPF_AND | BPF_X:
++	case BPF_ALU64 | BPF_OR | BPF_X:
++	case BPF_ALU64 | BPF_XOR | BPF_X:
++	case BPF_ALU64 | BPF_LSH | BPF_X:
++	case BPF_ALU64 | BPF_RSH | BPF_X:
++	case BPF_ALU64 | BPF_ARSH | BPF_X:
++	case BPF_ALU64 | BPF_ADD | BPF_X:
++	case BPF_ALU64 | BPF_SUB | BPF_X:
++	case BPF_ALU64 | BPF_MUL | BPF_X:
++	case BPF_ALU64 | BPF_DIV | BPF_X:
++	case BPF_ALU64 | BPF_MOD | BPF_X:
++		emit_alu_r64(ctx, dst, src, BPF_OP(code));
++		break;
++	/* dst = htole(dst) */
++	/* dst = htobe(dst) */
++	case BPF_ALU | BPF_END | BPF_FROM_LE:
++	case BPF_ALU | BPF_END | BPF_FROM_BE:
++		if (BPF_SRC(code) ==
++#ifdef __BIG_ENDIAN
++		    BPF_FROM_LE
++#else
++		    BPF_FROM_BE
++#endif
++		    )
++			emit_bswap_r64(ctx, dst, imm);
++		else
++			emit_trunc_r64(ctx, dst, imm);
++		break;
++	/* dst = imm64 */
++	case BPF_LD | BPF_IMM | BPF_DW:
++		emit_mov_i64(ctx, dst, (u32)imm | ((u64)insn[1].imm << 32));
++		return 1;
++	/* LDX: dst = *(size *)(src + off) */
++	case BPF_LDX | BPF_MEM | BPF_W:
++	case BPF_LDX | BPF_MEM | BPF_H:
++	case BPF_LDX | BPF_MEM | BPF_B:
++	case BPF_LDX | BPF_MEM | BPF_DW:
++		emit_ldx(ctx, dst, src, off, BPF_SIZE(code));
++		break;
++	/* ST: *(size *)(dst + off) = imm */
++	case BPF_ST | BPF_MEM | BPF_W:
++	case BPF_ST | BPF_MEM | BPF_H:
++	case BPF_ST | BPF_MEM | BPF_B:
++	case BPF_ST | BPF_MEM | BPF_DW:
++		emit_mov_i(ctx, MIPS_R_T4, imm);
++		emit_stx(ctx, dst, MIPS_R_T4, off, BPF_SIZE(code));
++		break;
++	/* STX: *(size *)(dst + off) = src */
++	case BPF_STX | BPF_MEM | BPF_W:
++	case BPF_STX | BPF_MEM | BPF_H:
++	case BPF_STX | BPF_MEM | BPF_B:
++	case BPF_STX | BPF_MEM | BPF_DW:
++		emit_stx(ctx, dst, src, off, BPF_SIZE(code));
++		break;
++	/* Speculation barrier */
++	case BPF_ST | BPF_NOSPEC:
++		break;
++	/* Atomics */
++	case BPF_STX | BPF_XADD | BPF_W:
++	case BPF_STX | BPF_XADD | BPF_DW:
++		switch (imm) {
++		case BPF_ADD:
++		case BPF_AND:
++		case BPF_OR:
++		case BPF_XOR:
++			if (BPF_SIZE(code) == BPF_DW) {
++				emit_atomic_r64(ctx, dst, src, off, imm);
++			} else { /* 32-bit, no fetch */
++				emit_sext(ctx, MIPS_R_T4, src);
++				emit_atomic_r(ctx, dst, MIPS_R_T4, off, imm);
++			}
++			break;
++		default:
++			goto notyet;
++		}
++		break;
++	/* PC += off if dst == src */
++	/* PC += off if dst != src */
++	/* PC += off if dst & src */
++	/* PC += off if dst > src */
++	/* PC += off if dst >= src */
++	/* PC += off if dst < src */
++	/* PC += off if dst <= src */
++	/* PC += off if dst > src (signed) */
++	/* PC += off if dst >= src (signed) */
++	/* PC += off if dst < src (signed) */
++	/* PC += off if dst <= src (signed) */
++	case BPF_JMP32 | BPF_JEQ | BPF_X:
++	case BPF_JMP32 | BPF_JNE | BPF_X:
++	case BPF_JMP32 | BPF_JSET | 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:
++		if (off == 0)
++			break;
++		setup_jmp_r(ctx, dst == src, BPF_OP(code), off, &jmp, &rel);
++		emit_sext(ctx, MIPS_R_T4, dst); /* Sign-extended dst */
++		emit_sext(ctx, MIPS_R_T5, src); /* Sign-extended src */
++		emit_jmp_r(ctx, MIPS_R_T4, MIPS_R_T5, rel, jmp);
++		if (finish_jmp(ctx, jmp, off) < 0)
++			goto toofar;
++		break;
++	/* PC += off if dst == imm */
++	/* PC += off if dst != imm */
++	/* PC += off if dst & imm */
++	/* PC += off if dst > imm */
++	/* PC += off if dst >= imm */
++	/* PC += off if dst < imm */
++	/* PC += off if dst <= imm */
++	/* PC += off if dst > imm (signed) */
++	/* PC += off if dst >= imm (signed) */
++	/* PC += off if dst < imm (signed) */
++	/* PC += off if dst <= imm (signed) */
++	case BPF_JMP32 | BPF_JEQ | BPF_K:
++	case BPF_JMP32 | BPF_JNE | BPF_K:
++	case BPF_JMP32 | BPF_JSET | 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:
++		if (off == 0)
++			break;
++		setup_jmp_i(ctx, imm, 32, BPF_OP(code), off, &jmp, &rel);
++		emit_sext(ctx, MIPS_R_T4, dst); /* Sign-extended dst */
++		if (valid_jmp_i(jmp, imm)) {
++			emit_jmp_i(ctx, MIPS_R_T4, imm, rel, jmp);
++		} else {
++			/* Move large immediate to register, sign-extended */
++			emit_mov_i(ctx, MIPS_R_T5, imm);
++			emit_jmp_r(ctx, MIPS_R_T4, MIPS_R_T5, rel, jmp);
++		}
++		if (finish_jmp(ctx, jmp, off) < 0)
++			goto toofar;
++		break;
++	/* PC += off if dst == src */
++	/* PC += off if dst != src */
++	/* PC += off if dst & src */
++	/* PC += off if dst > src */
++	/* PC += off if dst >= src */
++	/* PC += off if dst < src */
++	/* PC += off if dst <= src */
++	/* PC += off if dst > src (signed) */
++	/* PC += off if dst >= src (signed) */
++	/* PC += off if dst < src (signed) */
++	/* PC += off if dst <= src (signed) */
++	case BPF_JMP | BPF_JEQ | BPF_X:
++	case BPF_JMP | BPF_JNE | BPF_X:
++	case BPF_JMP | BPF_JSET | 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:
++		if (off == 0)
++			break;
++		setup_jmp_r(ctx, dst == src, BPF_OP(code), off, &jmp, &rel);
++		emit_jmp_r(ctx, dst, src, rel, jmp);
++		if (finish_jmp(ctx, jmp, off) < 0)
++			goto toofar;
++		break;
++	/* PC += off if dst == imm */
++	/* PC += off if dst != imm */
++	/* PC += off if dst & imm */
++	/* PC += off if dst > imm */
++	/* PC += off if dst >= imm */
++	/* PC += off if dst < imm */
++	/* PC += off if dst <= imm */
++	/* PC += off if dst > imm (signed) */
++	/* PC += off if dst >= imm (signed) */
++	/* PC += off if dst < imm (signed) */
++	/* PC += off if dst <= imm (signed) */
++	case BPF_JMP | BPF_JEQ | BPF_K:
++	case BPF_JMP | BPF_JNE | BPF_K:
++	case BPF_JMP | BPF_JSET | 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:
++		if (off == 0)
++			break;
++		setup_jmp_i(ctx, imm, 64, BPF_OP(code), off, &jmp, &rel);
++		if (valid_jmp_i(jmp, imm)) {
++			emit_jmp_i(ctx, dst, imm, rel, jmp);
++		} else {
++			/* Move large immediate to register */
++			emit_mov_i(ctx, MIPS_R_T4, imm);
++			emit_jmp_r(ctx, dst, MIPS_R_T4, rel, jmp);
++		}
++		if (finish_jmp(ctx, jmp, off) < 0)
++			goto toofar;
++		break;
++	/* PC += off */
++	case BPF_JMP | BPF_JA:
++		if (off == 0)
++			break;
++		if (emit_ja(ctx, off) < 0)
++			goto toofar;
++		break;
++	/* Tail call */
++	case BPF_JMP | BPF_TAIL_CALL:
++		if (emit_tail_call(ctx) < 0)
++			goto invalid;
++		break;
++	/* Function call */
++	case BPF_JMP | BPF_CALL:
++		if (emit_call(ctx, insn) < 0)
++			goto invalid;
++		break;
++	/* Function return */
++	case BPF_JMP | BPF_EXIT:
++		/*
++		 * Optimization: when last instruction is EXIT
++		 * simply continue to epilogue.
++		 */
++		if (ctx->bpf_index == ctx->program->len - 1)
++			break;
++		if (emit_exit(ctx) < 0)
++			goto toofar;
++		break;
++
++	default:
++invalid:
++		pr_err_once("unknown opcode %02x\n", code);
++		return -EINVAL;
++notyet:
++		pr_info_once("*** NOT YET: opcode %02x ***\n", code);
++		return -EFAULT;
++toofar:
++		pr_info_once("*** TOO FAR: jump at %u opcode %02x ***\n",
++			     ctx->bpf_index, code);
++		return -E2BIG;
++	}
++	return 0;
++}
diff --git a/target/linux/generic/backport-5.10/050-v5.16-04-mips-bpf-Add-JIT-workarounds-for-CPU-errata.patch b/target/linux/generic/backport-5.10/050-v5.16-04-mips-bpf-Add-JIT-workarounds-for-CPU-errata.patch
new file mode 100644
index 0000000000..63553ebe58
--- /dev/null
+++ b/target/linux/generic/backport-5.10/050-v5.16-04-mips-bpf-Add-JIT-workarounds-for-CPU-errata.patch
@@ -0,0 +1,120 @@
+From: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+Date: Tue, 5 Oct 2021 18:54:06 +0200
+Subject: [PATCH] mips: bpf: Add JIT workarounds for CPU errata
+
+This patch adds workarounds for the following CPU errata to the MIPS
+eBPF JIT, if enabled in the kernel configuration.
+
+  - R10000 ll/sc weak ordering
+  - Loongson-3 ll/sc weak ordering
+  - Loongson-2F jump hang
+
+The Loongson-2F nop errata is implemented in uasm, which the JIT uses,
+so no additional mitigations are needed for that.
+
+Signed-off-by: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+Reviewed-by: Jiaxun Yang <jiaxun.yang at flygoat.com>
+---
+
+--- a/arch/mips/net/bpf_jit_comp.c
++++ b/arch/mips/net/bpf_jit_comp.c
+@@ -404,6 +404,7 @@ void emit_alu_r(struct jit_context *ctx,
+ /* Atomic read-modify-write (32-bit) */
+ void emit_atomic_r(struct jit_context *ctx, u8 dst, u8 src, s16 off, u8 code)
+ {
++	LLSC_sync(ctx);
+ 	emit(ctx, ll, MIPS_R_T9, off, dst);
+ 	switch (code) {
+ 	case BPF_ADD:
+@@ -420,18 +421,19 @@ void emit_atomic_r(struct jit_context *c
+ 		break;
+ 	}
+ 	emit(ctx, sc, MIPS_R_T8, off, dst);
+-	emit(ctx, beqz, MIPS_R_T8, -16);
++	emit(ctx, LLSC_beqz, MIPS_R_T8, -16 - LLSC_offset);
+ 	emit(ctx, nop); /* Delay slot */
+ }
+ 
+ /* Atomic compare-and-exchange (32-bit) */
+ void emit_cmpxchg_r(struct jit_context *ctx, u8 dst, u8 src, u8 res, s16 off)
+ {
++	LLSC_sync(ctx);
+ 	emit(ctx, ll, MIPS_R_T9, off, dst);
+ 	emit(ctx, bne, MIPS_R_T9, res, 12);
+ 	emit(ctx, move, MIPS_R_T8, src);     /* Delay slot */
+ 	emit(ctx, sc, MIPS_R_T8, off, dst);
+-	emit(ctx, beqz, MIPS_R_T8, -20);
++	emit(ctx, LLSC_beqz, MIPS_R_T8, -20 - LLSC_offset);
+ 	emit(ctx, move, res, MIPS_R_T9);     /* Delay slot */
+ 	clobber_reg(ctx, res);
+ }
+--- a/arch/mips/net/bpf_jit_comp.h
++++ b/arch/mips/net/bpf_jit_comp.h
+@@ -87,7 +87,7 @@ struct jit_context {
+ };
+ 
+ /* Emit the instruction if the JIT memory space has been allocated */
+-#define emit(ctx, func, ...)					\
++#define __emit(ctx, func, ...)					\
+ do {								\
+ 	if ((ctx)->target != NULL) {				\
+ 		u32 *p = &(ctx)->target[ctx->jit_index];	\
+@@ -95,6 +95,30 @@ do {								\
+ 	}							\
+ 	(ctx)->jit_index++;					\
+ } while (0)
++#define emit(...) __emit(__VA_ARGS__)
++
++/* Workaround for R10000 ll/sc errata */
++#ifdef CONFIG_WAR_R10000
++#define LLSC_beqz	beqzl
++#else
++#define LLSC_beqz	beqz
++#endif
++
++/* Workaround for Loongson-3 ll/sc errata */
++#ifdef CONFIG_CPU_LOONGSON3_WORKAROUNDS
++#define LLSC_sync(ctx)	emit(ctx, sync, 0)
++#define LLSC_offset	4
++#else
++#define LLSC_sync(ctx)
++#define LLSC_offset	0
++#endif
++
++/* Workaround for Loongson-2F jump errata */
++#ifdef CONFIG_CPU_JUMP_WORKAROUNDS
++#define JALR_MASK	0xffffffffcfffffffULL
++#else
++#define JALR_MASK	(~0ULL)
++#endif
+ 
+ /*
+  * Mark a BPF register as accessed, it needs to be
+--- a/arch/mips/net/bpf_jit_comp64.c
++++ b/arch/mips/net/bpf_jit_comp64.c
+@@ -375,6 +375,7 @@ static void emit_atomic_r64(struct jit_c
+ 	u8 t1 = MIPS_R_T6;
+ 	u8 t2 = MIPS_R_T7;
+ 
++	LLSC_sync(ctx);
+ 	emit(ctx, lld, t1, off, dst);
+ 	switch (code) {
+ 	case BPF_ADD:
+@@ -391,7 +392,7 @@ static void emit_atomic_r64(struct jit_c
+ 		break;
+ 	}
+ 	emit(ctx, scd, t2, off, dst);
+-	emit(ctx, beqz, t2, -16);
++	emit(ctx, LLSC_beqz, t2, -16 - LLSC_offset);
+ 	emit(ctx, nop); /* Delay slot */
+ }
+ 
+@@ -414,7 +415,7 @@ static int emit_call(struct jit_context
+ 	push_regs(ctx, ctx->clobbered & JIT_CALLER_REGS, 0, 0);
+ 
+ 	/* Emit function call */
+-	emit_mov_i64(ctx, tmp, addr);
++	emit_mov_i64(ctx, tmp, addr & JALR_MASK);
+ 	emit(ctx, jalr, MIPS_R_RA, tmp);
+ 	emit(ctx, nop); /* Delay slot */
+ 
diff --git a/target/linux/generic/backport-5.10/050-v5.16-05-mips-bpf-Enable-eBPF-JITs.patch b/target/linux/generic/backport-5.10/050-v5.16-05-mips-bpf-Enable-eBPF-JITs.patch
new file mode 100644
index 0000000000..10685c5f3c
--- /dev/null
+++ b/target/linux/generic/backport-5.10/050-v5.16-05-mips-bpf-Enable-eBPF-JITs.patch
@@ -0,0 +1,61 @@
+From: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+Date: Tue, 5 Oct 2021 18:54:07 +0200
+Subject: [PATCH] mips: bpf: Enable eBPF JITs
+
+This patch enables the new eBPF JITs for 32-bit and 64-bit MIPS. It also
+disables the old cBPF JIT to so cBPF programs are converted to use the
+new JIT.
+
+Workarounds for R4000 CPU errata are not implemented by the JIT, so the
+JIT is disabled if any of those workarounds are configured.
+
+Signed-off-by: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+---
+
+--- a/MAINTAINERS
++++ b/MAINTAINERS
+@@ -3294,6 +3294,7 @@ S:	Supported
+ F:	arch/arm64/net/
+ 
+ BPF JIT for MIPS (32-BIT AND 64-BIT)
++M:	Johan Almbladh <johan.almbladh at anyfinetworks.com>
+ M:	Paul Burton <paulburton at kernel.org>
+ L:	netdev at vger.kernel.org
+ L:	bpf at vger.kernel.org
+--- a/arch/mips/Kconfig
++++ b/arch/mips/Kconfig
+@@ -49,7 +49,6 @@ config MIPS
+ 	select HAVE_ARCH_TRACEHOOK
+ 	select HAVE_ARCH_TRANSPARENT_HUGEPAGE if CPU_SUPPORTS_HUGEPAGES
+ 	select HAVE_ASM_MODVERSIONS
+-	select HAVE_CBPF_JIT if !64BIT && !CPU_MICROMIPS
+ 	select HAVE_CONTEXT_TRACKING
+ 	select HAVE_TIF_NOHZ
+ 	select HAVE_C_RECORDMCOUNT
+@@ -57,7 +56,10 @@ config MIPS
+ 	select HAVE_DEBUG_STACKOVERFLOW
+ 	select HAVE_DMA_CONTIGUOUS
+ 	select HAVE_DYNAMIC_FTRACE
+-	select HAVE_EBPF_JIT if 64BIT && !CPU_MICROMIPS && TARGET_ISA_REV >= 2
++	select HAVE_EBPF_JIT if !CPU_MICROMIPS && \
++				!CPU_DADDI_WORKAROUNDS && \
++				!CPU_R4000_WORKAROUNDS && \
++				!CPU_R4400_WORKAROUNDS
+ 	select HAVE_EXIT_THREAD
+ 	select HAVE_FAST_GUP
+ 	select HAVE_FTRACE_MCOUNT_RECORD
+--- a/arch/mips/net/Makefile
++++ b/arch/mips/net/Makefile
+@@ -2,9 +2,10 @@
+ # MIPS networking code
+ 
+ obj-$(CONFIG_MIPS_CBPF_JIT) += bpf_jit.o bpf_jit_asm.o
++obj-$(CONFIG_MIPS_EBPF_JIT) += bpf_jit_comp.o
+ 
+ ifeq ($(CONFIG_32BIT),y)
+-        obj-$(CONFIG_MIPS_EBPF_JIT) += bpf_jit_comp.o bpf_jit_comp32.o
++        obj-$(CONFIG_MIPS_EBPF_JIT) += bpf_jit_comp32.o
+ else
+-        obj-$(CONFIG_MIPS_EBPF_JIT) += ebpf_jit.o
++        obj-$(CONFIG_MIPS_EBPF_JIT) += bpf_jit_comp64.o
+ endif
diff --git a/target/linux/generic/backport-5.10/050-v5.16-06-mips-bpf-Remove-old-BPF-JIT-implementations.patch b/target/linux/generic/backport-5.10/050-v5.16-06-mips-bpf-Remove-old-BPF-JIT-implementations.patch
new file mode 100644
index 0000000000..e25c336831
--- /dev/null
+++ b/target/linux/generic/backport-5.10/050-v5.16-06-mips-bpf-Remove-old-BPF-JIT-implementations.patch
@@ -0,0 +1,387 @@
+From: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+Date: Tue, 5 Oct 2021 18:54:08 +0200
+Subject: [PATCH] mips: bpf: Remove old BPF JIT implementations
+
+This patch removes the old 32-bit cBPF and 64-bit eBPF JIT implementations.
+They are replaced by a new eBPF implementation that supports both 32-bit
+and 64-bit MIPS CPUs.
+
+Signed-off-by: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+---
+ delete mode 100644 arch/mips/net/bpf_jit.c
+ delete mode 100644 arch/mips/net/bpf_jit.h
+ delete mode 100644 arch/mips/net/bpf_jit_asm.S
+ delete mode 100644 arch/mips/net/ebpf_jit.c
+
+--- a/arch/mips/net/bpf_jit.h
++++ /dev/null
+@@ -1,81 +0,0 @@
+-/* SPDX-License-Identifier: GPL-2.0-only */
+-/*
+- * Just-In-Time compiler for BPF filters on MIPS
+- *
+- * Copyright (c) 2014 Imagination Technologies Ltd.
+- * Author: Markos Chandras <markos.chandras at imgtec.com>
+- */
+-
+-#ifndef BPF_JIT_MIPS_OP_H
+-#define BPF_JIT_MIPS_OP_H
+-
+-/* Registers used by JIT */
+-#define MIPS_R_ZERO	0
+-#define MIPS_R_V0	2
+-#define MIPS_R_A0	4
+-#define MIPS_R_A1	5
+-#define MIPS_R_T4	12
+-#define MIPS_R_T5	13
+-#define MIPS_R_T6	14
+-#define MIPS_R_T7	15
+-#define MIPS_R_S0	16
+-#define MIPS_R_S1	17
+-#define MIPS_R_S2	18
+-#define MIPS_R_S3	19
+-#define MIPS_R_S4	20
+-#define MIPS_R_S5	21
+-#define MIPS_R_S6	22
+-#define MIPS_R_S7	23
+-#define MIPS_R_SP	29
+-#define MIPS_R_RA	31
+-
+-/* Conditional codes */
+-#define MIPS_COND_EQ	0x1
+-#define MIPS_COND_GE	(0x1 << 1)
+-#define MIPS_COND_GT	(0x1 << 2)
+-#define MIPS_COND_NE	(0x1 << 3)
+-#define MIPS_COND_ALL	(0x1 << 4)
+-/* Conditionals on X register or K immediate */
+-#define MIPS_COND_X	(0x1 << 5)
+-#define MIPS_COND_K	(0x1 << 6)
+-
+-#define r_ret	MIPS_R_V0
+-
+-/*
+- * Use 2 scratch registers to avoid pipeline interlocks.
+- * There is no overhead during epilogue and prologue since
+- * any of the $s0-$s6 registers will only be preserved if
+- * they are going to actually be used.
+- */
+-#define r_skb_hl	MIPS_R_S0 /* skb header length */
+-#define r_skb_data	MIPS_R_S1 /* skb actual data */
+-#define r_off		MIPS_R_S2
+-#define r_A		MIPS_R_S3
+-#define r_X		MIPS_R_S4
+-#define r_skb		MIPS_R_S5
+-#define r_M		MIPS_R_S6
+-#define r_skb_len	MIPS_R_S7
+-#define r_s0		MIPS_R_T4 /* scratch reg 1 */
+-#define r_s1		MIPS_R_T5 /* scratch reg 2 */
+-#define r_tmp_imm	MIPS_R_T6 /* No need to preserve this */
+-#define r_tmp		MIPS_R_T7 /* No need to preserve this */
+-#define r_zero		MIPS_R_ZERO
+-#define r_sp		MIPS_R_SP
+-#define r_ra		MIPS_R_RA
+-
+-#ifndef __ASSEMBLY__
+-
+-/* Declare ASM helpers */
+-
+-#define DECLARE_LOAD_FUNC(func) \
+-	extern u8 func(unsigned long *skb, int offset); \
+-	extern u8 func##_negative(unsigned long *skb, int offset); \
+-	extern u8 func##_positive(unsigned long *skb, int offset)
+-
+-DECLARE_LOAD_FUNC(sk_load_word);
+-DECLARE_LOAD_FUNC(sk_load_half);
+-DECLARE_LOAD_FUNC(sk_load_byte);
+-
+-#endif
+-
+-#endif /* BPF_JIT_MIPS_OP_H */
+--- a/arch/mips/net/bpf_jit_asm.S
++++ /dev/null
+@@ -1,285 +0,0 @@
+-/*
+- * bpf_jib_asm.S: Packet/header access helper functions for MIPS/MIPS64 BPF
+- * compiler.
+- *
+- * Copyright (C) 2015 Imagination Technologies Ltd.
+- * Author: Markos Chandras <markos.chandras at imgtec.com>
+- *
+- * This program is free software; you can redistribute it and/or modify it
+- * under the terms of the GNU General Public License as published by the
+- * Free Software Foundation; version 2 of the License.
+- */
+-
+-#include <asm/asm.h>
+-#include <asm/isa-rev.h>
+-#include <asm/regdef.h>
+-#include "bpf_jit.h"
+-
+-/* ABI
+- *
+- * r_skb_hl	skb header length
+- * r_skb_data	skb data
+- * r_off(a1)	offset register
+- * r_A		BPF register A
+- * r_X		PF register X
+- * r_skb(a0)	*skb
+- * r_M		*scratch memory
+- * r_skb_le	skb length
+- * r_s0		Scratch register 0
+- * r_s1		Scratch register 1
+- *
+- * On entry:
+- * a0: *skb
+- * a1: offset (imm or imm + X)
+- *
+- * All non-BPF-ABI registers are free for use. On return, we only
+- * care about r_ret. The BPF-ABI registers are assumed to remain
+- * unmodified during the entire filter operation.
+- */
+-
+-#define skb	a0
+-#define offset	a1
+-#define SKF_LL_OFF  (-0x200000) /* Can't include linux/filter.h in assembly */
+-
+-	/* We know better :) so prevent assembler reordering etc */
+-	.set 	noreorder
+-
+-#define is_offset_negative(TYPE)				\
+-	/* If offset is negative we have more work to do */	\
+-	slti	t0, offset, 0;					\
+-	bgtz	t0, bpf_slow_path_##TYPE##_neg;			\
+-	/* Be careful what follows in DS. */
+-
+-#define is_offset_in_header(SIZE, TYPE)				\
+-	/* Reading from header? */				\
+-	addiu	$r_s0, $r_skb_hl, -SIZE;			\
+-	slt	t0, $r_s0, offset;				\
+-	bgtz	t0, bpf_slow_path_##TYPE;			\
+-
+-LEAF(sk_load_word)
+-	is_offset_negative(word)
+-FEXPORT(sk_load_word_positive)
+-	is_offset_in_header(4, word)
+-	/* Offset within header boundaries */
+-	PTR_ADDU t1, $r_skb_data, offset
+-	.set	reorder
+-	lw	$r_A, 0(t1)
+-	.set	noreorder
+-#ifdef CONFIG_CPU_LITTLE_ENDIAN
+-# if MIPS_ISA_REV >= 2
+-	wsbh	t0, $r_A
+-	rotr	$r_A, t0, 16
+-# else
+-	sll	t0, $r_A, 24
+-	srl	t1, $r_A, 24
+-	srl	t2, $r_A, 8
+-	or	t0, t0, t1
+-	andi	t2, t2, 0xff00
+-	andi	t1, $r_A, 0xff00
+-	or	t0, t0, t2
+-	sll	t1, t1, 8
+-	or	$r_A, t0, t1
+-# endif
+-#endif
+-	jr	$r_ra
+-	 move	$r_ret, zero
+-	END(sk_load_word)
+-
+-LEAF(sk_load_half)
+-	is_offset_negative(half)
+-FEXPORT(sk_load_half_positive)
+-	is_offset_in_header(2, half)
+-	/* Offset within header boundaries */
+-	PTR_ADDU t1, $r_skb_data, offset
+-	lhu	$r_A, 0(t1)
+-#ifdef CONFIG_CPU_LITTLE_ENDIAN
+-# if MIPS_ISA_REV >= 2
+-	wsbh	$r_A, $r_A
+-# else
+-	sll	t0, $r_A, 8
+-	srl	t1, $r_A, 8
+-	andi	t0, t0, 0xff00
+-	or	$r_A, t0, t1
+-# endif
+-#endif
+-	jr	$r_ra
+-	 move	$r_ret, zero
+-	END(sk_load_half)
+-
+-LEAF(sk_load_byte)
+-	is_offset_negative(byte)
+-FEXPORT(sk_load_byte_positive)
+-	is_offset_in_header(1, byte)
+-	/* Offset within header boundaries */
+-	PTR_ADDU t1, $r_skb_data, offset
+-	lbu	$r_A, 0(t1)
+-	jr	$r_ra
+-	 move	$r_ret, zero
+-	END(sk_load_byte)
+-
+-/*
+- * call skb_copy_bits:
+- * (prototype in linux/skbuff.h)
+- *
+- * int skb_copy_bits(sk_buff *skb, int offset, void *to, int len)
+- *
+- * o32 mandates we leave 4 spaces for argument registers in case
+- * the callee needs to use them. Even though we don't care about
+- * the argument registers ourselves, we need to allocate that space
+- * to remain ABI compliant since the callee may want to use that space.
+- * We also allocate 2 more spaces for $r_ra and our return register (*to).
+- *
+- * n64 is a bit different. The *caller* will allocate the space to preserve
+- * the arguments. So in 64-bit kernels, we allocate the 4-arg space for no
+- * good reason but it does not matter that much really.
+- *
+- * (void *to) is returned in r_s0
+- *
+- */
+-#ifdef CONFIG_CPU_LITTLE_ENDIAN
+-#define DS_OFFSET(SIZE) (4 * SZREG)
+-#else
+-#define DS_OFFSET(SIZE) ((4 * SZREG) + (4 - SIZE))
+-#endif
+-#define bpf_slow_path_common(SIZE)				\
+-	/* Quick check. Are we within reasonable boundaries? */ \
+-	LONG_ADDIU	$r_s1, $r_skb_len, -SIZE;		\
+-	sltu		$r_s0, offset, $r_s1;			\
+-	beqz		$r_s0, fault;				\
+-	/* Load 4th argument in DS */				\
+-	 LONG_ADDIU	a3, zero, SIZE;				\
+-	PTR_ADDIU	$r_sp, $r_sp, -(6 * SZREG);		\
+-	PTR_LA		t0, skb_copy_bits;			\
+-	PTR_S		$r_ra, (5 * SZREG)($r_sp);		\
+-	/* Assign low slot to a2 */				\
+-	PTR_ADDIU	a2, $r_sp, DS_OFFSET(SIZE);		\
+-	jalr		t0;					\
+-	/* Reset our destination slot (DS but it's ok) */	\
+-	 INT_S		zero, (4 * SZREG)($r_sp);		\
+-	/*							\
+-	 * skb_copy_bits returns 0 on success and -EFAULT	\
+-	 * on error. Our data live in a2. Do not bother with	\
+-	 * our data if an error has been returned.		\
+-	 */							\
+-	/* Restore our frame */					\
+-	PTR_L		$r_ra, (5 * SZREG)($r_sp);		\
+-	INT_L		$r_s0, (4 * SZREG)($r_sp);		\
+-	bltz		v0, fault;				\
+-	 PTR_ADDIU	$r_sp, $r_sp, 6 * SZREG;		\
+-	move		$r_ret, zero;				\
+-
+-NESTED(bpf_slow_path_word, (6 * SZREG), $r_sp)
+-	bpf_slow_path_common(4)
+-#ifdef CONFIG_CPU_LITTLE_ENDIAN
+-# if MIPS_ISA_REV >= 2
+-	wsbh	t0, $r_s0
+-	jr	$r_ra
+-	 rotr	$r_A, t0, 16
+-# else
+-	sll	t0, $r_s0, 24
+-	srl	t1, $r_s0, 24
+-	srl	t2, $r_s0, 8
+-	or	t0, t0, t1
+-	andi	t2, t2, 0xff00
+-	andi	t1, $r_s0, 0xff00
+-	or	t0, t0, t2
+-	sll	t1, t1, 8
+-	jr	$r_ra
+-	 or	$r_A, t0, t1
+-# endif
+-#else
+-	jr	$r_ra
+-	 move	$r_A, $r_s0
+-#endif
+-
+-	END(bpf_slow_path_word)
+-
+-NESTED(bpf_slow_path_half, (6 * SZREG), $r_sp)
+-	bpf_slow_path_common(2)
+-#ifdef CONFIG_CPU_LITTLE_ENDIAN
+-# if MIPS_ISA_REV >= 2
+-	jr	$r_ra
+-	 wsbh	$r_A, $r_s0
+-# else
+-	sll	t0, $r_s0, 8
+-	andi	t1, $r_s0, 0xff00
+-	andi	t0, t0, 0xff00
+-	srl	t1, t1, 8
+-	jr	$r_ra
+-	 or	$r_A, t0, t1
+-# endif
+-#else
+-	jr	$r_ra
+-	 move	$r_A, $r_s0
+-#endif
+-
+-	END(bpf_slow_path_half)
+-
+-NESTED(bpf_slow_path_byte, (6 * SZREG), $r_sp)
+-	bpf_slow_path_common(1)
+-	jr	$r_ra
+-	 move	$r_A, $r_s0
+-
+-	END(bpf_slow_path_byte)
+-
+-/*
+- * Negative entry points
+- */
+-	.macro bpf_is_end_of_data
+-	li	t0, SKF_LL_OFF
+-	/* Reading link layer data? */
+-	slt	t1, offset, t0
+-	bgtz	t1, fault
+-	/* Be careful what follows in DS. */
+-	.endm
+-/*
+- * call skb_copy_bits:
+- * (prototype in linux/filter.h)
+- *
+- * void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb,
+- *                                            int k, unsigned int size)
+- *
+- * see above (bpf_slow_path_common) for ABI restrictions
+- */
+-#define bpf_negative_common(SIZE)					\
+-	PTR_ADDIU	$r_sp, $r_sp, -(6 * SZREG);			\
+-	PTR_LA		t0, bpf_internal_load_pointer_neg_helper;	\
+-	PTR_S		$r_ra, (5 * SZREG)($r_sp);			\
+-	jalr		t0;						\
+-	 li		a2, SIZE;					\
+-	PTR_L		$r_ra, (5 * SZREG)($r_sp);			\
+-	/* Check return pointer */					\
+-	beqz		v0, fault;					\
+-	 PTR_ADDIU	$r_sp, $r_sp, 6 * SZREG;			\
+-	/* Preserve our pointer */					\
+-	move		$r_s0, v0;					\
+-	/* Set return value */						\
+-	move		$r_ret, zero;					\
+-
+-bpf_slow_path_word_neg:
+-	bpf_is_end_of_data
+-NESTED(sk_load_word_negative, (6 * SZREG), $r_sp)
+-	bpf_negative_common(4)
+-	jr	$r_ra
+-	 lw	$r_A, 0($r_s0)
+-	END(sk_load_word_negative)
+-
+-bpf_slow_path_half_neg:
+-	bpf_is_end_of_data
+-NESTED(sk_load_half_negative, (6 * SZREG), $r_sp)
+-	bpf_negative_common(2)
+-	jr	$r_ra
+-	 lhu	$r_A, 0($r_s0)
+-	END(sk_load_half_negative)
+-
+-bpf_slow_path_byte_neg:
+-	bpf_is_end_of_data
+-NESTED(sk_load_byte_negative, (6 * SZREG), $r_sp)
+-	bpf_negative_common(1)
+-	jr	$r_ra
+-	 lbu	$r_A, 0($r_s0)
+-	END(sk_load_byte_negative)
+-
+-fault:
+-	jr	$r_ra
+-	 addiu $r_ret, zero, 1
diff --git a/target/linux/generic/backport-5.10/103-v5.13-MIPS-select-CPU_MIPS64-for-remaining-MIPS64-CPUs.patch b/target/linux/generic/backport-5.10/103-v5.13-MIPS-select-CPU_MIPS64-for-remaining-MIPS64-CPUs.patch
index 83bfd733d6..7e34bae8b4 100644
--- a/target/linux/generic/backport-5.10/103-v5.13-MIPS-select-CPU_MIPS64-for-remaining-MIPS64-CPUs.patch
+++ b/target/linux/generic/backport-5.10/103-v5.13-MIPS-select-CPU_MIPS64-for-remaining-MIPS64-CPUs.patch
@@ -25,7 +25,7 @@ Signed-off-by: Jason A. Donenfeld <Jason at zx2c4.com>
 
 --- a/arch/mips/Kconfig
 +++ b/arch/mips/Kconfig
-@@ -2078,7 +2078,7 @@ config CPU_MIPS32
+@@ -2080,7 +2080,7 @@ config CPU_MIPS32
  config CPU_MIPS64
  	bool
  	default y if CPU_MIPS64_R1 || CPU_MIPS64_R2 || CPU_MIPS64_R5 || \
diff --git a/target/linux/generic/backport-5.4/071-v5.16-00-MIPS-uasm-Enable-muhu-opcode-for-MIPS-R6.patch b/target/linux/generic/backport-5.4/071-v5.16-00-MIPS-uasm-Enable-muhu-opcode-for-MIPS-R6.patch
new file mode 100644
index 0000000000..82feb7421d
--- /dev/null
+++ b/target/linux/generic/backport-5.4/071-v5.16-00-MIPS-uasm-Enable-muhu-opcode-for-MIPS-R6.patch
@@ -0,0 +1,65 @@
+From: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+Date: Tue, 5 Oct 2021 18:54:02 +0200
+Subject: [PATCH] MIPS: uasm: Enable muhu opcode for MIPS R6
+
+Enable the 'muhu' instruction, complementing the existing 'mulu', needed
+to implement a MIPS32 BPF JIT.
+
+Also fix a typo in the existing definition of 'dmulu'.
+
+Signed-off-by: Tony Ambardar <Tony.Ambardar at gmail.com>
+
+This patch is a dependency for my 32-bit MIPS eBPF JIT.
+
+Signed-off-by: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+---
+
+--- a/arch/mips/include/asm/uasm.h
++++ b/arch/mips/include/asm/uasm.h
+@@ -145,6 +145,7 @@ Ip_u1(_mtlo);
+ Ip_u3u1u2(_mul);
+ Ip_u1u2(_multu);
+ Ip_u3u1u2(_mulu);
++Ip_u3u1u2(_muhu);
+ Ip_u3u1u2(_nor);
+ Ip_u3u1u2(_or);
+ Ip_u2u1u3(_ori);
+--- a/arch/mips/mm/uasm-mips.c
++++ b/arch/mips/mm/uasm-mips.c
+@@ -90,7 +90,7 @@ static const struct insn insn_table[insn
+ 				RS | RT | RD},
+ 	[insn_dmtc0]	= {M(cop0_op, dmtc_op, 0, 0, 0, 0), RT | RD | SET},
+ 	[insn_dmultu]	= {M(spec_op, 0, 0, 0, 0, dmultu_op), RS | RT},
+-	[insn_dmulu]	= {M(spec_op, 0, 0, 0, dmult_dmul_op, dmultu_op),
++	[insn_dmulu]	= {M(spec_op, 0, 0, 0, dmultu_dmulu_op, dmultu_op),
+ 				RS | RT | RD},
+ 	[insn_drotr]	= {M(spec_op, 1, 0, 0, 0, dsrl_op), RT | RD | RE},
+ 	[insn_drotr32]	= {M(spec_op, 1, 0, 0, 0, dsrl32_op), RT | RD | RE},
+@@ -150,6 +150,8 @@ static const struct insn insn_table[insn
+ 	[insn_mtlo]	= {M(spec_op, 0, 0, 0, 0, mtlo_op), RS},
+ 	[insn_mulu]	= {M(spec_op, 0, 0, 0, multu_mulu_op, multu_op),
+ 				RS | RT | RD},
++	[insn_muhu]	= {M(spec_op, 0, 0, 0, multu_muhu_op, multu_op),
++				RS | RT | RD},
+ #ifndef CONFIG_CPU_MIPSR6
+ 	[insn_mul]	= {M(spec2_op, 0, 0, 0, 0, mul_op), RS | RT | RD},
+ #else
+--- a/arch/mips/mm/uasm.c
++++ b/arch/mips/mm/uasm.c
+@@ -59,7 +59,7 @@ enum opcode {
+ 	insn_lddir, insn_ldpte, insn_ldx, insn_lh, insn_lhu, insn_ll, insn_lld,
+ 	insn_lui, insn_lw, insn_lwu, insn_lwx, insn_mfc0, insn_mfhc0, insn_mfhi,
+ 	insn_mflo, insn_modu, insn_movn, insn_movz, insn_mtc0, insn_mthc0,
+-	insn_mthi, insn_mtlo, insn_mul, insn_multu, insn_mulu, insn_nor,
++	insn_mthi, insn_mtlo, insn_mul, insn_multu, insn_mulu, insn_muhu, insn_nor,
+ 	insn_or, insn_ori, insn_pref, insn_rfe, insn_rotr, insn_sb, insn_sc,
+ 	insn_scd, insn_seleqz, insn_selnez, insn_sd, insn_sh, insn_sll,
+ 	insn_sllv, insn_slt, insn_slti, insn_sltiu, insn_sltu, insn_sra,
+@@ -344,6 +344,7 @@ I_u1(_mtlo)
+ I_u3u1u2(_mul)
+ I_u1u2(_multu)
+ I_u3u1u2(_mulu)
++I_u3u1u2(_muhu)
+ I_u3u1u2(_nor)
+ I_u3u1u2(_or)
+ I_u2u1u3(_ori)
diff --git a/target/linux/generic/backport-5.4/071-v5.16-01-mips-uasm-Add-workaround-for-Loongson-2F-nop-CPU-err.patch b/target/linux/generic/backport-5.4/071-v5.16-01-mips-uasm-Add-workaround-for-Loongson-2F-nop-CPU-err.patch
new file mode 100644
index 0000000000..3a4d573f80
--- /dev/null
+++ b/target/linux/generic/backport-5.4/071-v5.16-01-mips-uasm-Add-workaround-for-Loongson-2F-nop-CPU-err.patch
@@ -0,0 +1,31 @@
+From: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+Date: Tue, 5 Oct 2021 18:54:03 +0200
+Subject: [PATCH] mips: uasm: Add workaround for Loongson-2F nop CPU errata
+
+This patch implements a workaround for the Loongson-2F nop in generated,
+code, if the existing option CONFIG_CPU_NOP_WORKAROUND is set. Before,
+the binutils option -mfix-loongson2f-nop was enabled, but no workaround
+was done when emitting MIPS code. Now, the nop pseudo instruction is
+emitted as "or ax,ax,zero" instead of the default "sll zero,zero,0". This
+is consistent with the workaround implemented by binutils.
+
+Link: https://sourceware.org/legacy-ml/binutils/2009-11/msg00387.html
+
+Signed-off-by: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+Reviewed-by: Jiaxun Yang <jiaxun.yang at flygoat.com>
+---
+
+--- a/arch/mips/include/asm/uasm.h
++++ b/arch/mips/include/asm/uasm.h
+@@ -249,7 +249,11 @@ static inline void uasm_l##lb(struct uas
+ #define uasm_i_bnezl(buf, rs, off) uasm_i_bnel(buf, rs, 0, off)
+ #define uasm_i_ehb(buf) uasm_i_sll(buf, 0, 0, 3)
+ #define uasm_i_move(buf, a, b) UASM_i_ADDU(buf, a, 0, b)
++#ifdef CONFIG_CPU_NOP_WORKAROUNDS
++#define uasm_i_nop(buf) uasm_i_or(buf, 1, 1, 0)
++#else
+ #define uasm_i_nop(buf) uasm_i_sll(buf, 0, 0, 0)
++#endif
+ #define uasm_i_ssnop(buf) uasm_i_sll(buf, 0, 0, 1)
+ 
+ static inline void uasm_i_drotr_safe(u32 **p, unsigned int a1,
diff --git a/target/linux/generic/backport-5.4/071-v5.16-02-mips-bpf-Add-eBPF-JIT-for-32-bit-MIPS.patch b/target/linux/generic/backport-5.4/071-v5.16-02-mips-bpf-Add-eBPF-JIT-for-32-bit-MIPS.patch
new file mode 100644
index 0000000000..7980659961
--- /dev/null
+++ b/target/linux/generic/backport-5.4/071-v5.16-02-mips-bpf-Add-eBPF-JIT-for-32-bit-MIPS.patch
@@ -0,0 +1,3078 @@
+From: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+Date: Tue, 5 Oct 2021 18:54:04 +0200
+Subject: [PATCH] mips: bpf: Add eBPF JIT for 32-bit MIPS
+
+This is an implementation of an eBPF JIT for 32-bit MIPS I-V and MIPS32.
+The implementation supports all 32-bit and 64-bit ALU and JMP operations,
+including the recently-added atomics. 64-bit div/mod and 64-bit atomics
+are implemented using function calls to math64 and atomic64 functions,
+respectively. All 32-bit operations are implemented natively by the JIT,
+except if the CPU lacks ll/sc instructions.
+
+Register mapping
+================
+All 64-bit eBPF registers are mapped to native 32-bit MIPS register pairs,
+and does not use any stack scratch space for register swapping. This means
+that all eBPF register data is kept in CPU registers all the time, and
+this simplifies the register management a lot. It also reduces the JIT's
+pressure on temporary registers since we do not have to move data around.
+
+Native register pairs are ordered according to CPU endiannes, following
+the O32 calling convention for passing 64-bit arguments and return values.
+The eBPF return value, arguments and callee-saved registers are mapped to
+their native MIPS equivalents.
+
+Since the 32 highest bits in the eBPF FP (frame pointer) register are
+always zero, only one general-purpose register is actually needed for the
+mapping. The MIPS fp register is used for this purpose. The high bits are
+mapped to MIPS register r0. This saves us one CPU register, which is much
+needed for temporaries, while still allowing us to treat the R10 (FP)
+register just like any other eBPF register in the JIT.
+
+The MIPS gp (global pointer) and at (assembler temporary) registers are
+used as internal temporary registers for constant blinding. CPU registers
+t6-t9 are used internally by the JIT when constructing more complex 64-bit
+operations. This is precisely what is needed - two registers to store an
+operand value, and two more as scratch registers when performing the
+operation.
+
+The register mapping is shown below.
+
+    R0 - $v1, $v0   return value
+    R1 - $a1, $a0   argument 1, passed in registers
+    R2 - $a3, $a2   argument 2, passed in registers
+    R3 - $t1, $t0   argument 3, passed on stack
+    R4 - $t3, $t2   argument 4, passed on stack
+    R5 - $t4, $t3   argument 5, passed on stack
+    R6 - $s1, $s0   callee-saved
+    R7 - $s3, $s2   callee-saved
+    R8 - $s5, $s4   callee-saved
+    R9 - $s7, $s6   callee-saved
+    FP - $r0, $fp   32-bit frame pointer
+    AX - $gp, $at   constant-blinding
+         $t6 - $t9  unallocated, JIT temporaries
+
+Jump offsets
+============
+The JIT tries to map all conditional JMP operations to MIPS conditional
+PC-relative branches. The MIPS branch offset field is 18 bits, in bytes,
+which is equivalent to the eBPF 16-bit instruction offset. However, since
+the JIT may emit more than one CPU instruction per eBPF instruction, the
+field width may overflow. If that happens, the JIT converts the long
+conditional jump to a short PC-relative branch with the condition
+inverted, jumping over a long unconditional absolute jmp (j).
+
+This conversion will change the instruction offset mapping used for jumps,
+and may in turn result in more branch offset overflows. The JIT therefore
+dry-runs the translation until no more branches are converted and the
+offsets do not change anymore. There is an upper bound on this of course,
+and if the JIT hits that limit, the last two iterations are run with all
+branches being converted.
+
+Tail call count
+===============
+The current tail call count is stored in the 16-byte area of the caller's
+stack frame that is reserved for the callee in the o32 ABI. The value is
+initialized in the prologue, and propagated to the tail-callee by skipping
+the initialization instructions when emitting the tail call.
+
+Signed-off-by: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+---
+ create mode 100644 arch/mips/net/bpf_jit_comp.c
+ create mode 100644 arch/mips/net/bpf_jit_comp.h
+ create mode 100644 arch/mips/net/bpf_jit_comp32.c
+
+--- a/arch/mips/net/Makefile
++++ b/arch/mips/net/Makefile
+@@ -2,4 +2,9 @@
+ # MIPS networking code
+ 
+ obj-$(CONFIG_MIPS_CBPF_JIT) += bpf_jit.o bpf_jit_asm.o
+-obj-$(CONFIG_MIPS_EBPF_JIT) += ebpf_jit.o
++
++ifeq ($(CONFIG_32BIT),y)
++        obj-$(CONFIG_MIPS_EBPF_JIT) += bpf_jit_comp.o bpf_jit_comp32.o
++else
++        obj-$(CONFIG_MIPS_EBPF_JIT) += ebpf_jit.o
++endif
+--- /dev/null
++++ b/arch/mips/net/bpf_jit_comp.c
+@@ -0,0 +1,1020 @@
++// SPDX-License-Identifier: GPL-2.0-only
++/*
++ * Just-In-Time compiler for eBPF bytecode on MIPS.
++ * Implementation of JIT functions common to 32-bit and 64-bit CPUs.
++ *
++ * Copyright (c) 2021 Anyfi Networks AB.
++ * Author: Johan Almbladh <johan.almbladh at gmail.com>
++ *
++ * Based on code and ideas from
++ * Copyright (c) 2017 Cavium, Inc.
++ * Copyright (c) 2017 Shubham Bansal <illusionist.neo at gmail.com>
++ * Copyright (c) 2011 Mircea Gherzan <mgherzan at gmail.com>
++ */
++
++/*
++ * Code overview
++ * =============
++ *
++ * - bpf_jit_comp.h
++ *   Common definitions and utilities.
++ *
++ * - bpf_jit_comp.c
++ *   Implementation of JIT top-level logic and exported JIT API functions.
++ *   Implementation of internal operations shared by 32-bit and 64-bit code.
++ *   JMP and ALU JIT control code, register control code, shared ALU and
++ *   JMP/JMP32 JIT operations.
++ *
++ * - bpf_jit_comp32.c
++ *   Implementation of functions to JIT prologue, epilogue and a single eBPF
++ *   instruction for 32-bit MIPS CPUs. The functions use shared operations
++ *   where possible, and implement the rest for 32-bit MIPS such as ALU64
++ *   operations.
++ *
++ * - bpf_jit_comp64.c
++ *   Ditto, for 64-bit MIPS CPUs.
++ *
++ * Zero and sign extension
++ * ========================
++ * 32-bit MIPS instructions on 64-bit MIPS registers use sign extension,
++ * but the eBPF instruction set mandates zero extension. We let the verifier
++ * insert explicit zero-extensions after 32-bit ALU operations, both for
++ * 32-bit and 64-bit MIPS JITs. Conditional JMP32 operations on 64-bit MIPs
++ * are JITed with sign extensions inserted when so expected.
++ *
++ * ALU operations
++ * ==============
++ * ALU operations on 32/64-bit MIPS and ALU64 operations on 64-bit MIPS are
++ * JITed in the following steps. ALU64 operations on 32-bit MIPS are more
++ * complicated and therefore only processed by special implementations in
++ * step (3).
++ *
++ * 1) valid_alu_i:
++ *    Determine if an immediate operation can be emitted as such, or if
++ *    we must fall back to the register version.
++ *
++ * 2) rewrite_alu_i:
++ *    Convert BPF operation and immediate value to a canonical form for
++ *    JITing. In some degenerate cases this form may be a no-op.
++ *
++ * 3) emit_alu_{i,i64,r,64}:
++ *    Emit instructions for an ALU or ALU64 immediate or register operation.
++ *
++ * JMP operations
++ * ==============
++ * JMP and JMP32 operations require an JIT instruction offset table for
++ * translating the jump offset. This table is computed by dry-running the
++ * JIT without actually emitting anything. However, the computed PC-relative
++ * offset may overflow the 18-bit offset field width of the native MIPS
++ * branch instruction. In such cases, the long jump is converted into the
++ * following sequence.
++ *
++ *    <branch> !<cond> +2    Inverted PC-relative branch
++ *    nop                    Delay slot
++ *    j <offset>             Unconditional absolute long jump
++ *    nop                    Delay slot
++ *
++ * Since this converted sequence alters the offset table, all offsets must
++ * be re-calculated. This may in turn trigger new branch conversions, so
++ * the process is repeated until no further changes are made. Normally it
++ * completes in 1-2 iterations. If JIT_MAX_ITERATIONS should reached, we
++ * fall back to converting every remaining jump operation. The branch
++ * conversion is independent of how the JMP or JMP32 condition is JITed.
++ *
++ * JMP32 and JMP operations are JITed as follows.
++ *
++ * 1) setup_jmp_{i,r}:
++ *    Convert jump conditional and offset into a form that can be JITed.
++ *    This form may be a no-op, a canonical form, or an inverted PC-relative
++ *    jump if branch conversion is necessary.
++ *
++ * 2) valid_jmp_i:
++ *    Determine if an immediate operations can be emitted as such, or if
++ *    we must fall back to the register version. Applies to JMP32 for 32-bit
++ *    MIPS, and both JMP and JMP32 for 64-bit MIPS.
++ *
++ * 3) emit_jmp_{i,i64,r,r64}:
++ *    Emit instructions for an JMP or JMP32 immediate or register operation.
++ *
++ * 4) finish_jmp_{i,r}:
++ *    Emit any instructions needed to finish the jump. This includes a nop
++ *    for the delay slot if a branch was emitted, and a long absolute jump
++ *    if the branch was converted.
++ */
++
++#include <linux/limits.h>
++#include <linux/bitops.h>
++#include <linux/errno.h>
++#include <linux/filter.h>
++#include <linux/bpf.h>
++#include <linux/slab.h>
++#include <asm/bitops.h>
++#include <asm/cacheflush.h>
++#include <asm/cpu-features.h>
++#include <asm/isa-rev.h>
++#include <asm/uasm.h>
++
++#include "bpf_jit_comp.h"
++
++/* Convenience macros for descriptor access */
++#define CONVERTED(desc)	((desc) & JIT_DESC_CONVERT)
++#define INDEX(desc)	((desc) & ~JIT_DESC_CONVERT)
++
++/*
++ * Push registers on the stack, starting at a given depth from the stack
++ * pointer and increasing. The next depth to be written is returned.
++ */
++int push_regs(struct jit_context *ctx, u32 mask, u32 excl, int depth)
++{
++	int reg;
++
++	for (reg = 0; reg < BITS_PER_BYTE * sizeof(mask); reg++)
++		if (mask & BIT(reg)) {
++			if ((excl & BIT(reg)) == 0) {
++				if (sizeof(long) == 4)
++					emit(ctx, sw, reg, depth, MIPS_R_SP);
++				else /* sizeof(long) == 8 */
++					emit(ctx, sd, reg, depth, MIPS_R_SP);
++			}
++			depth += sizeof(long);
++		}
++
++	ctx->stack_used = max((int)ctx->stack_used, depth);
++	return depth;
++}
++
++/*
++ * Pop registers from the stack, starting at a given depth from the stack
++ * pointer and increasing. The next depth to be read is returned.
++ */
++int pop_regs(struct jit_context *ctx, u32 mask, u32 excl, int depth)
++{
++	int reg;
++
++	for (reg = 0; reg < BITS_PER_BYTE * sizeof(mask); reg++)
++		if (mask & BIT(reg)) {
++			if ((excl & BIT(reg)) == 0) {
++				if (sizeof(long) == 4)
++					emit(ctx, lw, reg, depth, MIPS_R_SP);
++				else /* sizeof(long) == 8 */
++					emit(ctx, ld, reg, depth, MIPS_R_SP);
++			}
++			depth += sizeof(long);
++		}
++
++	return depth;
++}
++
++/* Compute the 28-bit jump target address from a BPF program location */
++int get_target(struct jit_context *ctx, u32 loc)
++{
++	u32 index = INDEX(ctx->descriptors[loc]);
++	unsigned long pc = (unsigned long)&ctx->target[ctx->jit_index];
++	unsigned long addr = (unsigned long)&ctx->target[index];
++
++	if (!ctx->target)
++		return 0;
++
++	if ((addr ^ pc) & ~MIPS_JMP_MASK)
++		return -1;
++
++	return addr & MIPS_JMP_MASK;
++}
++
++/* Compute the PC-relative offset to relative BPF program offset */
++int get_offset(const struct jit_context *ctx, int off)
++{
++	return (INDEX(ctx->descriptors[ctx->bpf_index + off]) -
++		ctx->jit_index - 1) * sizeof(u32);
++}
++
++/* dst = imm (register width) */
++void emit_mov_i(struct jit_context *ctx, u8 dst, s32 imm)
++{
++	if (imm >= -0x8000 && imm <= 0x7fff) {
++		emit(ctx, addiu, dst, MIPS_R_ZERO, imm);
++	} else {
++		emit(ctx, lui, dst, (s16)((u32)imm >> 16));
++		emit(ctx, ori, dst, dst, (u16)(imm & 0xffff));
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* dst = src (register width) */
++void emit_mov_r(struct jit_context *ctx, u8 dst, u8 src)
++{
++	emit(ctx, ori, dst, src, 0);
++	clobber_reg(ctx, dst);
++}
++
++/* Validate ALU immediate range */
++bool valid_alu_i(u8 op, s32 imm)
++{
++	switch (BPF_OP(op)) {
++	case BPF_NEG:
++	case BPF_LSH:
++	case BPF_RSH:
++	case BPF_ARSH:
++		/* All legal eBPF values are valid */
++		return true;
++	case BPF_ADD:
++		/* imm must be 16 bits */
++		return imm >= -0x8000 && imm <= 0x7fff;
++	case BPF_SUB:
++		/* -imm must be 16 bits */
++		return imm >= -0x7fff && imm <= 0x8000;
++	case BPF_AND:
++	case BPF_OR:
++	case BPF_XOR:
++		/* imm must be 16 bits unsigned */
++		return imm >= 0 && imm <= 0xffff;
++	case BPF_MUL:
++		/* imm must be zero or a positive power of two */
++		return imm == 0 || (imm > 0 && is_power_of_2(imm));
++	case BPF_DIV:
++	case BPF_MOD:
++		/* imm must be an 17-bit power of two */
++		return (u32)imm <= 0x10000 && is_power_of_2((u32)imm);
++	}
++	return false;
++}
++
++/* Rewrite ALU immediate operation */
++bool rewrite_alu_i(u8 op, s32 imm, u8 *alu, s32 *val)
++{
++	bool act = true;
++
++	switch (BPF_OP(op)) {
++	case BPF_LSH:
++	case BPF_RSH:
++	case BPF_ARSH:
++	case BPF_ADD:
++	case BPF_SUB:
++	case BPF_OR:
++	case BPF_XOR:
++		/* imm == 0 is a no-op */
++		act = imm != 0;
++		break;
++	case BPF_MUL:
++		if (imm == 1) {
++			/* dst * 1 is a no-op */
++			act = false;
++		} else if (imm == 0) {
++			/* dst * 0 is dst & 0 */
++			op = BPF_AND;
++		} else {
++			/* dst * (1 << n) is dst << n */
++			op = BPF_LSH;
++			imm = ilog2(abs(imm));
++		}
++		break;
++	case BPF_DIV:
++		if (imm == 1) {
++			/* dst / 1 is a no-op */
++			act = false;
++		} else {
++			/* dst / (1 << n) is dst >> n */
++			op = BPF_RSH;
++			imm = ilog2(imm);
++		}
++		break;
++	case BPF_MOD:
++		/* dst % (1 << n) is dst & ((1 << n) - 1) */
++		op = BPF_AND;
++		imm--;
++		break;
++	}
++
++	*alu = op;
++	*val = imm;
++	return act;
++}
++
++/* ALU immediate operation (32-bit) */
++void emit_alu_i(struct jit_context *ctx, u8 dst, s32 imm, u8 op)
++{
++	switch (BPF_OP(op)) {
++	/* dst = -dst */
++	case BPF_NEG:
++		emit(ctx, subu, dst, MIPS_R_ZERO, dst);
++		break;
++	/* dst = dst & imm */
++	case BPF_AND:
++		emit(ctx, andi, dst, dst, (u16)imm);
++		break;
++	/* dst = dst | imm */
++	case BPF_OR:
++		emit(ctx, ori, dst, dst, (u16)imm);
++		break;
++	/* dst = dst ^ imm */
++	case BPF_XOR:
++		emit(ctx, xori, dst, dst, (u16)imm);
++		break;
++	/* dst = dst << imm */
++	case BPF_LSH:
++		emit(ctx, sll, dst, dst, imm);
++		break;
++	/* dst = dst >> imm */
++	case BPF_RSH:
++		emit(ctx, srl, dst, dst, imm);
++		break;
++	/* dst = dst >> imm (arithmetic) */
++	case BPF_ARSH:
++		emit(ctx, sra, dst, dst, imm);
++		break;
++	/* dst = dst + imm */
++	case BPF_ADD:
++		emit(ctx, addiu, dst, dst, imm);
++		break;
++	/* dst = dst - imm */
++	case BPF_SUB:
++		emit(ctx, addiu, dst, dst, -imm);
++		break;
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* ALU register operation (32-bit) */
++void emit_alu_r(struct jit_context *ctx, u8 dst, u8 src, u8 op)
++{
++	switch (BPF_OP(op)) {
++	/* dst = dst & src */
++	case BPF_AND:
++		emit(ctx, and, dst, dst, src);
++		break;
++	/* dst = dst | src */
++	case BPF_OR:
++		emit(ctx, or, dst, dst, src);
++		break;
++	/* dst = dst ^ src */
++	case BPF_XOR:
++		emit(ctx, xor, dst, dst, src);
++		break;
++	/* dst = dst << src */
++	case BPF_LSH:
++		emit(ctx, sllv, dst, dst, src);
++		break;
++	/* dst = dst >> src */
++	case BPF_RSH:
++		emit(ctx, srlv, dst, dst, src);
++		break;
++	/* dst = dst >> src (arithmetic) */
++	case BPF_ARSH:
++		emit(ctx, srav, dst, dst, src);
++		break;
++	/* dst = dst + src */
++	case BPF_ADD:
++		emit(ctx, addu, dst, dst, src);
++		break;
++	/* dst = dst - src */
++	case BPF_SUB:
++		emit(ctx, subu, dst, dst, src);
++		break;
++	/* dst = dst * src */
++	case BPF_MUL:
++		if (cpu_has_mips32r1 || cpu_has_mips32r6) {
++			emit(ctx, mul, dst, dst, src);
++		} else {
++			emit(ctx, multu, dst, src);
++			emit(ctx, mflo, dst);
++		}
++		break;
++	/* dst = dst / src */
++	case BPF_DIV:
++		if (cpu_has_mips32r6) {
++			emit(ctx, divu_r6, dst, dst, src);
++		} else {
++			emit(ctx, divu, dst, src);
++			emit(ctx, mflo, dst);
++		}
++		break;
++	/* dst = dst % src */
++	case BPF_MOD:
++		if (cpu_has_mips32r6) {
++			emit(ctx, modu, dst, dst, src);
++		} else {
++			emit(ctx, divu, dst, src);
++			emit(ctx, mfhi, dst);
++		}
++		break;
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* Atomic read-modify-write (32-bit) */
++void emit_atomic_r(struct jit_context *ctx, u8 dst, u8 src, s16 off, u8 code)
++{
++	emit(ctx, ll, MIPS_R_T9, off, dst);
++	switch (code) {
++	case BPF_ADD:
++		emit(ctx, addu, MIPS_R_T8, MIPS_R_T9, src);
++		break;
++	case BPF_AND:
++		emit(ctx, and, MIPS_R_T8, MIPS_R_T9, src);
++		break;
++	case BPF_OR:
++		emit(ctx, or, MIPS_R_T8, MIPS_R_T9, src);
++		break;
++	case BPF_XOR:
++		emit(ctx, xor, MIPS_R_T8, MIPS_R_T9, src);
++		break;
++	}
++	emit(ctx, sc, MIPS_R_T8, off, dst);
++	emit(ctx, beqz, MIPS_R_T8, -16);
++	emit(ctx, nop); /* Delay slot */
++}
++
++/* Atomic compare-and-exchange (32-bit) */
++void emit_cmpxchg_r(struct jit_context *ctx, u8 dst, u8 src, u8 res, s16 off)
++{
++	emit(ctx, ll, MIPS_R_T9, off, dst);
++	emit(ctx, bne, MIPS_R_T9, res, 12);
++	emit(ctx, move, MIPS_R_T8, src);     /* Delay slot */
++	emit(ctx, sc, MIPS_R_T8, off, dst);
++	emit(ctx, beqz, MIPS_R_T8, -20);
++	emit(ctx, move, res, MIPS_R_T9);     /* Delay slot */
++	clobber_reg(ctx, res);
++}
++
++/* Swap bytes and truncate a register word or half word */
++void emit_bswap_r(struct jit_context *ctx, u8 dst, u32 width)
++{
++	u8 tmp = MIPS_R_T8;
++	u8 msk = MIPS_R_T9;
++
++	switch (width) {
++	/* Swap bytes in a word */
++	case 32:
++		if (cpu_has_mips32r2 || cpu_has_mips32r6) {
++			emit(ctx, wsbh, dst, dst);
++			emit(ctx, rotr, dst, dst, 16);
++		} else {
++			emit(ctx, sll, tmp, dst, 16);    /* tmp  = dst << 16 */
++			emit(ctx, srl, dst, dst, 16);    /* dst = dst >> 16  */
++			emit(ctx, or, dst, dst, tmp);    /* dst = dst | tmp  */
++
++			emit(ctx, lui, msk, 0xff);       /* msk = 0x00ff0000 */
++			emit(ctx, ori, msk, msk, 0xff);  /* msk = msk | 0xff */
++
++			emit(ctx, and, tmp, dst, msk);   /* tmp = dst & msk  */
++			emit(ctx, sll, tmp, tmp, 8);     /* tmp = tmp << 8   */
++			emit(ctx, srl, dst, dst, 8);     /* dst = dst >> 8   */
++			emit(ctx, and, dst, dst, msk);   /* dst = dst & msk  */
++			emit(ctx, or, dst, dst, tmp);    /* reg = dst | tmp  */
++		}
++		break;
++	/* Swap bytes in a half word */
++	case 16:
++		if (cpu_has_mips32r2 || cpu_has_mips32r6) {
++			emit(ctx, wsbh, dst, dst);
++			emit(ctx, andi, dst, dst, 0xffff);
++		} else {
++			emit(ctx, andi, tmp, dst, 0xff00); /* t = d & 0xff00 */
++			emit(ctx, srl, tmp, tmp, 8);       /* t = t >> 8     */
++			emit(ctx, andi, dst, dst, 0x00ff); /* d = d & 0x00ff */
++			emit(ctx, sll, dst, dst, 8);       /* d = d << 8     */
++			emit(ctx, or,  dst, dst, tmp);     /* d = d | t      */
++		}
++		break;
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* Validate jump immediate range */
++bool valid_jmp_i(u8 op, s32 imm)
++{
++	switch (op) {
++	case JIT_JNOP:
++		/* Immediate value not used */
++		return true;
++	case BPF_JEQ:
++	case BPF_JNE:
++		/* No immediate operation */
++		return false;
++	case BPF_JSET:
++	case JIT_JNSET:
++		/* imm must be 16 bits unsigned */
++		return imm >= 0 && imm <= 0xffff;
++	case BPF_JGE:
++	case BPF_JLT:
++	case BPF_JSGE:
++	case BPF_JSLT:
++		/* imm must be 16 bits */
++		return imm >= -0x8000 && imm <= 0x7fff;
++	case BPF_JGT:
++	case BPF_JLE:
++	case BPF_JSGT:
++	case BPF_JSLE:
++		/* imm + 1 must be 16 bits */
++		return imm >= -0x8001 && imm <= 0x7ffe;
++	}
++	return false;
++}
++
++/* Invert a conditional jump operation */
++static u8 invert_jmp(u8 op)
++{
++	switch (op) {
++	case BPF_JA: return JIT_JNOP;
++	case BPF_JEQ: return BPF_JNE;
++	case BPF_JNE: return BPF_JEQ;
++	case BPF_JSET: return JIT_JNSET;
++	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 0;
++}
++
++/* Prepare a PC-relative jump operation */
++static void setup_jmp(struct jit_context *ctx, u8 bpf_op,
++		      s16 bpf_off, u8 *jit_op, s32 *jit_off)
++{
++	u32 *descp = &ctx->descriptors[ctx->bpf_index];
++	int op = bpf_op;
++	int offset = 0;
++
++	/* Do not compute offsets on the first pass */
++	if (INDEX(*descp) == 0)
++		goto done;
++
++	/* Skip jumps never taken */
++	if (bpf_op == JIT_JNOP)
++		goto done;
++
++	/* Convert jumps always taken */
++	if (bpf_op == BPF_JA)
++		*descp |= JIT_DESC_CONVERT;
++
++	/*
++	 * Current ctx->jit_index points to the start of the branch preamble.
++	 * Since the preamble differs among different branch conditionals,
++	 * the current index cannot be used to compute the branch offset.
++	 * Instead, we use the offset table value for the next instruction,
++	 * which gives the index immediately after the branch delay slot.
++	 */
++	if (!CONVERTED(*descp)) {
++		int target = ctx->bpf_index + bpf_off + 1;
++		int origin = ctx->bpf_index + 1;
++
++		offset = (INDEX(ctx->descriptors[target]) -
++			  INDEX(ctx->descriptors[origin]) + 1) * sizeof(u32);
++	}
++
++	/*
++	 * The PC-relative branch offset field on MIPS is 18 bits signed,
++	 * so if the computed offset is larger than this we generate a an
++	 * absolute jump that we skip with an inverted conditional branch.
++	 */
++	if (CONVERTED(*descp) || offset < -0x20000 || offset > 0x1ffff) {
++		offset = 3 * sizeof(u32);
++		op = invert_jmp(bpf_op);
++		ctx->changes += !CONVERTED(*descp);
++		*descp |= JIT_DESC_CONVERT;
++	}
++
++done:
++	*jit_off = offset;
++	*jit_op = op;
++}
++
++/* Prepare a PC-relative jump operation with immediate conditional */
++void setup_jmp_i(struct jit_context *ctx, s32 imm, u8 width,
++		 u8 bpf_op, s16 bpf_off, u8 *jit_op, s32 *jit_off)
++{
++	bool always = false;
++	bool never = false;
++
++	switch (bpf_op) {
++	case BPF_JEQ:
++	case BPF_JNE:
++		break;
++	case BPF_JSET:
++	case BPF_JLT:
++		never = imm == 0;
++		break;
++	case BPF_JGE:
++		always = imm == 0;
++		break;
++	case BPF_JGT:
++		never = (u32)imm == U32_MAX;
++		break;
++	case BPF_JLE:
++		always = (u32)imm == U32_MAX;
++		break;
++	case BPF_JSGT:
++		never = imm == S32_MAX && width == 32;
++		break;
++	case BPF_JSGE:
++		always = imm == S32_MIN && width == 32;
++		break;
++	case BPF_JSLT:
++		never = imm == S32_MIN && width == 32;
++		break;
++	case BPF_JSLE:
++		always = imm == S32_MAX && width == 32;
++		break;
++	}
++
++	if (never)
++		bpf_op = JIT_JNOP;
++	if (always)
++		bpf_op = BPF_JA;
++	setup_jmp(ctx, bpf_op, bpf_off, jit_op, jit_off);
++}
++
++/* Prepare a PC-relative jump operation with register conditional */
++void setup_jmp_r(struct jit_context *ctx, bool same_reg,
++		 u8 bpf_op, s16 bpf_off, u8 *jit_op, s32 *jit_off)
++{
++	switch (bpf_op) {
++	case BPF_JSET:
++		break;
++	case BPF_JEQ:
++	case BPF_JGE:
++	case BPF_JLE:
++	case BPF_JSGE:
++	case BPF_JSLE:
++		if (same_reg)
++			bpf_op = BPF_JA;
++		break;
++	case BPF_JNE:
++	case BPF_JLT:
++	case BPF_JGT:
++	case BPF_JSGT:
++	case BPF_JSLT:
++		if (same_reg)
++			bpf_op = JIT_JNOP;
++		break;
++	}
++	setup_jmp(ctx, bpf_op, bpf_off, jit_op, jit_off);
++}
++
++/* Finish a PC-relative jump operation */
++int finish_jmp(struct jit_context *ctx, u8 jit_op, s16 bpf_off)
++{
++	/* Emit conditional branch delay slot */
++	if (jit_op != JIT_JNOP)
++		emit(ctx, nop);
++	/*
++	 * Emit an absolute long jump with delay slot,
++	 * if the PC-relative branch was converted.
++	 */
++	if (CONVERTED(ctx->descriptors[ctx->bpf_index])) {
++		int target = get_target(ctx, ctx->bpf_index + bpf_off + 1);
++
++		if (target < 0)
++			return -1;
++		emit(ctx, j, target);
++		emit(ctx, nop);
++	}
++	return 0;
++}
++
++/* Jump immediate (32-bit) */
++void emit_jmp_i(struct jit_context *ctx, u8 dst, s32 imm, s32 off, u8 op)
++{
++	switch (op) {
++	/* No-op, used internally for branch optimization */
++	case JIT_JNOP:
++		break;
++	/* PC += off if dst & imm */
++	case BPF_JSET:
++		emit(ctx, andi, MIPS_R_T9, dst, (u16)imm);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	/* PC += off if (dst & imm) == 0 (not in BPF, used for long jumps) */
++	case JIT_JNSET:
++		emit(ctx, andi, MIPS_R_T9, dst, (u16)imm);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst > imm */
++	case BPF_JGT:
++		emit(ctx, sltiu, MIPS_R_T9, dst, imm + 1);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst >= imm */
++	case BPF_JGE:
++		emit(ctx, sltiu, MIPS_R_T9, dst, imm);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst < imm */
++	case BPF_JLT:
++		emit(ctx, sltiu, MIPS_R_T9, dst, imm);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst <= imm */
++	case BPF_JLE:
++		emit(ctx, sltiu, MIPS_R_T9, dst, imm + 1);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst > imm (signed) */
++	case BPF_JSGT:
++		emit(ctx, slti, MIPS_R_T9, dst, imm + 1);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst >= imm (signed) */
++	case BPF_JSGE:
++		emit(ctx, slti, MIPS_R_T9, dst, imm);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst < imm (signed) */
++	case BPF_JSLT:
++		emit(ctx, slti, MIPS_R_T9, dst, imm);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst <= imm (signed) */
++	case BPF_JSLE:
++		emit(ctx, slti, MIPS_R_T9, dst, imm + 1);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	}
++}
++
++/* Jump register (32-bit) */
++void emit_jmp_r(struct jit_context *ctx, u8 dst, u8 src, s32 off, u8 op)
++{
++	switch (op) {
++	/* No-op, used internally for branch optimization */
++	case JIT_JNOP:
++		break;
++	/* PC += off if dst == src */
++	case BPF_JEQ:
++		emit(ctx, beq, dst, src, off);
++		break;
++	/* PC += off if dst != src */
++	case BPF_JNE:
++		emit(ctx, bne, dst, src, off);
++		break;
++	/* PC += off if dst & src */
++	case BPF_JSET:
++		emit(ctx, and, MIPS_R_T9, dst, src);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	/* PC += off if (dst & imm) == 0 (not in BPF, used for long jumps) */
++	case JIT_JNSET:
++		emit(ctx, and, MIPS_R_T9, dst, src);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst > src */
++	case BPF_JGT:
++		emit(ctx, sltu, MIPS_R_T9, src, dst);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst >= src */
++	case BPF_JGE:
++		emit(ctx, sltu, MIPS_R_T9, dst, src);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst < src */
++	case BPF_JLT:
++		emit(ctx, sltu, MIPS_R_T9, dst, src);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst <= src */
++	case BPF_JLE:
++		emit(ctx, sltu, MIPS_R_T9, src, dst);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst > src (signed) */
++	case BPF_JSGT:
++		emit(ctx, slt, MIPS_R_T9, src, dst);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst >= src (signed) */
++	case BPF_JSGE:
++		emit(ctx, slt, MIPS_R_T9, dst, src);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst < src (signed) */
++	case BPF_JSLT:
++		emit(ctx, slt, MIPS_R_T9, dst, src);
++		emit(ctx, bnez, MIPS_R_T9, off);
++		break;
++	/* PC += off if dst <= src (signed) */
++	case BPF_JSLE:
++		emit(ctx, slt, MIPS_R_T9, src, dst);
++		emit(ctx, beqz, MIPS_R_T9, off);
++		break;
++	}
++}
++
++/* Jump always */
++int emit_ja(struct jit_context *ctx, s16 off)
++{
++	int target = get_target(ctx, ctx->bpf_index + off + 1);
++
++	if (target < 0)
++		return -1;
++	emit(ctx, j, target);
++	emit(ctx, nop);
++	return 0;
++}
++
++/* Jump to epilogue */
++int emit_exit(struct jit_context *ctx)
++{
++	int target = get_target(ctx, ctx->program->len);
++
++	if (target < 0)
++		return -1;
++	emit(ctx, j, target);
++	emit(ctx, nop);
++	return 0;
++}
++
++/* Build the program body from eBPF bytecode */
++static int build_body(struct jit_context *ctx)
++{
++	const struct bpf_prog *prog = ctx->program;
++	unsigned int i;
++
++	ctx->stack_used = 0;
++	for (i = 0; i < prog->len; i++) {
++		const struct bpf_insn *insn = &prog->insnsi[i];
++		u32 *descp = &ctx->descriptors[i];
++		int ret;
++
++		access_reg(ctx, insn->src_reg);
++		access_reg(ctx, insn->dst_reg);
++
++		ctx->bpf_index = i;
++		if (ctx->target == NULL) {
++			ctx->changes += INDEX(*descp) != ctx->jit_index;
++			*descp &= JIT_DESC_CONVERT;
++			*descp |= ctx->jit_index;
++		}
++
++		ret = build_insn(insn, ctx);
++		if (ret < 0)
++			return ret;
++
++		if (ret > 0) {
++			i++;
++			if (ctx->target == NULL)
++				descp[1] = ctx->jit_index;
++		}
++	}
++
++	/* Store the end offset, where the epilogue begins */
++	ctx->descriptors[prog->len] = ctx->jit_index;
++	return 0;
++}
++
++/* Set the branch conversion flag on all instructions */
++static void set_convert_flag(struct jit_context *ctx, bool enable)
++{
++	const struct bpf_prog *prog = ctx->program;
++	u32 flag = enable ? JIT_DESC_CONVERT : 0;
++	unsigned int i;
++
++	for (i = 0; i <= prog->len; i++)
++		ctx->descriptors[i] = INDEX(ctx->descriptors[i]) | flag;
++}
++
++static void jit_fill_hole(void *area, unsigned int size)
++{
++	u32 *p;
++
++	/* We are guaranteed to have aligned memory. */
++	for (p = area; size >= sizeof(u32); size -= sizeof(u32))
++		uasm_i_break(&p, BRK_BUG); /* Increments p */
++}
++
++bool bpf_jit_needs_zext(void)
++{
++	return true;
++}
++
++struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
++{
++	struct bpf_prog *tmp, *orig_prog = prog;
++	struct bpf_binary_header *header = NULL;
++	struct jit_context ctx;
++	bool tmp_blinded = false;
++	unsigned int tmp_idx;
++	unsigned int image_size;
++	u8 *image_ptr;
++	int tries;
++
++	/*
++	 * If BPF JIT was not enabled then we must fall back to
++	 * the interpreter.
++	 */
++	if (!prog->jit_requested)
++		return orig_prog;
++	/*
++	 * If constant blinding was enabled and we failed during blinding
++	 * then we must fall back to the interpreter. Otherwise, we save
++	 * the new JITed code.
++	 */
++	tmp = bpf_jit_blind_constants(prog);
++	if (IS_ERR(tmp))
++		return orig_prog;
++	if (tmp != prog) {
++		tmp_blinded = true;
++		prog = tmp;
++	}
++
++	memset(&ctx, 0, sizeof(ctx));
++	ctx.program = prog;
++
++	/*
++	 * Not able to allocate memory for descriptors[], then
++	 * we must fall back to the interpreter
++	 */
++	ctx.descriptors = kcalloc(prog->len + 1, sizeof(*ctx.descriptors),
++				  GFP_KERNEL);
++	if (ctx.descriptors == NULL)
++		goto out_err;
++
++	/* First pass discovers used resources */
++	if (build_body(&ctx) < 0)
++		goto out_err;
++	/*
++	 * Second pass computes instruction offsets.
++	 * If any PC-relative branches are out of range, a sequence of
++	 * a PC-relative branch + a jump is generated, and we have to
++	 * try again from the beginning to generate the new offsets.
++	 * This is done until no additional conversions are necessary.
++	 * The last two iterations are done with all branches being
++	 * converted, to guarantee offset table convergence within a
++	 * fixed number of iterations.
++	 */
++	ctx.jit_index = 0;
++	build_prologue(&ctx);
++	tmp_idx = ctx.jit_index;
++
++	tries = JIT_MAX_ITERATIONS;
++	do {
++		ctx.jit_index = tmp_idx;
++		ctx.changes = 0;
++		if (tries == 2)
++			set_convert_flag(&ctx, true);
++		if (build_body(&ctx) < 0)
++			goto out_err;
++	} while (ctx.changes > 0 && --tries > 0);
++
++	if (WARN_ONCE(ctx.changes > 0, "JIT offsets failed to converge"))
++		goto out_err;
++
++	build_epilogue(&ctx, MIPS_R_RA);
++
++	/* Now we know the size of the structure to make */
++	image_size = sizeof(u32) * ctx.jit_index;
++	header = bpf_jit_binary_alloc(image_size, &image_ptr,
++				      sizeof(u32), jit_fill_hole);
++	/*
++	 * Not able to allocate memory for the structure then
++	 * we must fall back to the interpretation
++	 */
++	if (header == NULL)
++		goto out_err;
++
++	/* Actual pass to generate final JIT code */
++	ctx.target = (u32 *)image_ptr;
++	ctx.jit_index = 0;
++
++	/*
++	 * If building the JITed code fails somehow,
++	 * we fall back to the interpretation.
++	 */
++	build_prologue(&ctx);
++	if (build_body(&ctx) < 0)
++		goto out_err;
++	build_epilogue(&ctx, MIPS_R_RA);
++
++	/* Populate line info meta data */
++	set_convert_flag(&ctx, false);
++	bpf_prog_fill_jited_linfo(prog, &ctx.descriptors[1]);
++
++	/* Set as read-only exec and flush instruction cache */
++	bpf_jit_binary_lock_ro(header);
++	flush_icache_range((unsigned long)header,
++			   (unsigned long)&ctx.target[ctx.jit_index]);
++
++	if (bpf_jit_enable > 1)
++		bpf_jit_dump(prog->len, image_size, 2, ctx.target);
++
++	prog->bpf_func = (void *)ctx.target;
++	prog->jited = 1;
++	prog->jited_len = image_size;
++
++out:
++	if (tmp_blinded)
++		bpf_jit_prog_release_other(prog, prog == orig_prog ?
++					   tmp : orig_prog);
++	kfree(ctx.descriptors);
++	return prog;
++
++out_err:
++	prog = orig_prog;
++	if (header)
++		bpf_jit_binary_free(header);
++	goto out;
++}
+--- /dev/null
++++ b/arch/mips/net/bpf_jit_comp.h
+@@ -0,0 +1,211 @@
++/* SPDX-License-Identifier: GPL-2.0-only */
++/*
++ * Just-In-Time compiler for eBPF bytecode on 32-bit and 64-bit MIPS.
++ *
++ * Copyright (c) 2021 Anyfi Networks AB.
++ * Author: Johan Almbladh <johan.almbladh at gmail.com>
++ *
++ * Based on code and ideas from
++ * Copyright (c) 2017 Cavium, Inc.
++ * Copyright (c) 2017 Shubham Bansal <illusionist.neo at gmail.com>
++ * Copyright (c) 2011 Mircea Gherzan <mgherzan at gmail.com>
++ */
++
++#ifndef _BPF_JIT_COMP_H
++#define _BPF_JIT_COMP_H
++
++/* MIPS registers */
++#define MIPS_R_ZERO	0   /* Const zero */
++#define MIPS_R_AT	1   /* Asm temp   */
++#define MIPS_R_V0	2   /* Result     */
++#define MIPS_R_V1	3   /* Result     */
++#define MIPS_R_A0	4   /* Argument   */
++#define MIPS_R_A1	5   /* Argument   */
++#define MIPS_R_A2	6   /* Argument   */
++#define MIPS_R_A3	7   /* Argument   */
++#define MIPS_R_A4	8   /* Arg (n64)  */
++#define MIPS_R_A5	9   /* Arg (n64)  */
++#define MIPS_R_A6	10  /* Arg (n64)  */
++#define MIPS_R_A7	11  /* Arg (n64)  */
++#define MIPS_R_T0	8   /* Temp (o32) */
++#define MIPS_R_T1	9   /* Temp (o32) */
++#define MIPS_R_T2	10  /* Temp (o32) */
++#define MIPS_R_T3	11  /* Temp (o32) */
++#define MIPS_R_T4	12  /* Temporary  */
++#define MIPS_R_T5	13  /* Temporary  */
++#define MIPS_R_T6	14  /* Temporary  */
++#define MIPS_R_T7	15  /* Temporary  */
++#define MIPS_R_S0	16  /* Saved      */
++#define MIPS_R_S1	17  /* Saved      */
++#define MIPS_R_S2	18  /* Saved      */
++#define MIPS_R_S3	19  /* Saved      */
++#define MIPS_R_S4	20  /* Saved      */
++#define MIPS_R_S5	21  /* Saved      */
++#define MIPS_R_S6	22  /* Saved      */
++#define MIPS_R_S7	23  /* Saved      */
++#define MIPS_R_T8	24  /* Temporary  */
++#define MIPS_R_T9	25  /* Temporary  */
++/*      MIPS_R_K0	26     Reserved   */
++/*      MIPS_R_K1	27     Reserved   */
++#define MIPS_R_GP	28  /* Global ptr */
++#define MIPS_R_SP	29  /* Stack ptr  */
++#define MIPS_R_FP	30  /* Frame ptr  */
++#define MIPS_R_RA	31  /* Return     */
++
++/*
++ * Jump address mask for immediate jumps. The four most significant bits
++ * must be equal to PC.
++ */
++#define MIPS_JMP_MASK	0x0fffffffUL
++
++/* Maximum number of iterations in offset table computation */
++#define JIT_MAX_ITERATIONS	8
++
++/*
++ * Jump pseudo-instructions used internally
++ * for branch conversion and branch optimization.
++ */
++#define JIT_JNSET	0xe0
++#define JIT_JNOP	0xf0
++
++/* Descriptor flag for PC-relative branch conversion */
++#define JIT_DESC_CONVERT	BIT(31)
++
++/* JIT context for an eBPF program */
++struct jit_context {
++	struct bpf_prog *program;     /* The eBPF program being JITed        */
++	u32 *descriptors;             /* eBPF to JITed CPU insn descriptors  */
++	u32 *target;                  /* JITed code buffer                   */
++	u32 bpf_index;                /* Index of current BPF program insn   */
++	u32 jit_index;                /* Index of current JIT target insn    */
++	u32 changes;                  /* Number of PC-relative branch conv   */
++	u32 accessed;                 /* Bit mask of read eBPF registers     */
++	u32 clobbered;                /* Bit mask of modified CPU registers  */
++	u32 stack_size;               /* Total allocated stack size in bytes */
++	u32 saved_size;               /* Size of callee-saved registers      */
++	u32 stack_used;               /* Stack size used for function calls  */
++};
++
++/* Emit the instruction if the JIT memory space has been allocated */
++#define emit(ctx, func, ...)					\
++do {								\
++	if ((ctx)->target != NULL) {				\
++		u32 *p = &(ctx)->target[ctx->jit_index];	\
++		uasm_i_##func(&p, ##__VA_ARGS__);		\
++	}							\
++	(ctx)->jit_index++;					\
++} while (0)
++
++/*
++ * Mark a BPF register as accessed, it needs to be
++ * initialized by the program if expected, e.g. FP.
++ */
++static inline void access_reg(struct jit_context *ctx, u8 reg)
++{
++	ctx->accessed |= BIT(reg);
++}
++
++/*
++ * Mark a CPU register as clobbered, it needs to be
++ * saved/restored by the program if callee-saved.
++ */
++static inline void clobber_reg(struct jit_context *ctx, u8 reg)
++{
++	ctx->clobbered |= BIT(reg);
++}
++
++/*
++ * Push registers on the stack, starting at a given depth from the stack
++ * pointer and increasing. The next depth to be written is returned.
++ */
++int push_regs(struct jit_context *ctx, u32 mask, u32 excl, int depth);
++
++/*
++ * Pop registers from the stack, starting at a given depth from the stack
++ * pointer and increasing. The next depth to be read is returned.
++ */
++int pop_regs(struct jit_context *ctx, u32 mask, u32 excl, int depth);
++
++/* Compute the 28-bit jump target address from a BPF program location */
++int get_target(struct jit_context *ctx, u32 loc);
++
++/* Compute the PC-relative offset to relative BPF program offset */
++int get_offset(const struct jit_context *ctx, int off);
++
++/* dst = imm (32-bit) */
++void emit_mov_i(struct jit_context *ctx, u8 dst, s32 imm);
++
++/* dst = src (32-bit) */
++void emit_mov_r(struct jit_context *ctx, u8 dst, u8 src);
++
++/* Validate ALU/ALU64 immediate range */
++bool valid_alu_i(u8 op, s32 imm);
++
++/* Rewrite ALU/ALU64 immediate operation */
++bool rewrite_alu_i(u8 op, s32 imm, u8 *alu, s32 *val);
++
++/* ALU immediate operation (32-bit) */
++void emit_alu_i(struct jit_context *ctx, u8 dst, s32 imm, u8 op);
++
++/* ALU register operation (32-bit) */
++void emit_alu_r(struct jit_context *ctx, u8 dst, u8 src, u8 op);
++
++/* Atomic read-modify-write (32-bit) */
++void emit_atomic_r(struct jit_context *ctx, u8 dst, u8 src, s16 off, u8 code);
++
++/* Atomic compare-and-exchange (32-bit) */
++void emit_cmpxchg_r(struct jit_context *ctx, u8 dst, u8 src, u8 res, s16 off);
++
++/* Swap bytes and truncate a register word or half word */
++void emit_bswap_r(struct jit_context *ctx, u8 dst, u32 width);
++
++/* Validate JMP/JMP32 immediate range */
++bool valid_jmp_i(u8 op, s32 imm);
++
++/* Prepare a PC-relative jump operation with immediate conditional */
++void setup_jmp_i(struct jit_context *ctx, s32 imm, u8 width,
++		 u8 bpf_op, s16 bpf_off, u8 *jit_op, s32 *jit_off);
++
++/* Prepare a PC-relative jump operation with register conditional */
++void setup_jmp_r(struct jit_context *ctx, bool same_reg,
++		 u8 bpf_op, s16 bpf_off, u8 *jit_op, s32 *jit_off);
++
++/* Finish a PC-relative jump operation */
++int finish_jmp(struct jit_context *ctx, u8 jit_op, s16 bpf_off);
++
++/* Conditional JMP/JMP32 immediate */
++void emit_jmp_i(struct jit_context *ctx, u8 dst, s32 imm, s32 off, u8 op);
++
++/* Conditional JMP/JMP32 register */
++void emit_jmp_r(struct jit_context *ctx, u8 dst, u8 src, s32 off, u8 op);
++
++/* Jump always */
++int emit_ja(struct jit_context *ctx, s16 off);
++
++/* Jump to epilogue */
++int emit_exit(struct jit_context *ctx);
++
++/*
++ * Build program prologue to set up the stack and registers.
++ * This function is implemented separately for 32-bit and 64-bit JITs.
++ */
++void build_prologue(struct jit_context *ctx);
++
++/*
++ * Build the program epilogue to restore the stack and registers.
++ * This function is implemented separately for 32-bit and 64-bit JITs.
++ */
++void build_epilogue(struct jit_context *ctx, int dest_reg);
++
++/*
++ * Convert an eBPF instruction to native instruction, i.e
++ * JITs an eBPF instruction.
++ * Returns :
++ *	0  - Successfully JITed an 8-byte eBPF instruction
++ *	>0 - Successfully JITed a 16-byte eBPF instruction
++ *	<0 - Failed to JIT.
++ * This function is implemented separately for 32-bit and 64-bit JITs.
++ */
++int build_insn(const struct bpf_insn *insn, struct jit_context *ctx);
++
++#endif /* _BPF_JIT_COMP_H */
+--- /dev/null
++++ b/arch/mips/net/bpf_jit_comp32.c
+@@ -0,0 +1,1741 @@
++// SPDX-License-Identifier: GPL-2.0-only
++/*
++ * Just-In-Time compiler for eBPF bytecode on MIPS.
++ * Implementation of JIT functions for 32-bit CPUs.
++ *
++ * Copyright (c) 2021 Anyfi Networks AB.
++ * Author: Johan Almbladh <johan.almbladh at gmail.com>
++ *
++ * Based on code and ideas from
++ * Copyright (c) 2017 Cavium, Inc.
++ * Copyright (c) 2017 Shubham Bansal <illusionist.neo at gmail.com>
++ * Copyright (c) 2011 Mircea Gherzan <mgherzan at gmail.com>
++ */
++
++#include <linux/math64.h>
++#include <linux/errno.h>
++#include <linux/filter.h>
++#include <linux/bpf.h>
++#include <asm/cpu-features.h>
++#include <asm/isa-rev.h>
++#include <asm/uasm.h>
++
++#include "bpf_jit_comp.h"
++
++/* MIPS a4-a7 are not available in the o32 ABI */
++#undef MIPS_R_A4
++#undef MIPS_R_A5
++#undef MIPS_R_A6
++#undef MIPS_R_A7
++
++/* Stack is 8-byte aligned in o32 ABI */
++#define MIPS_STACK_ALIGNMENT 8
++
++/*
++ * The top 16 bytes of a stack frame is reserved for the callee in O32 ABI.
++ * This corresponds to stack space for register arguments a0-a3.
++ */
++#define JIT_RESERVED_STACK 16
++
++/* Temporary 64-bit register used by JIT */
++#define JIT_REG_TMP MAX_BPF_JIT_REG
++
++/*
++ * Number of prologue bytes to skip when doing a tail call.
++ * Tail call count (TCC) initialization (8 bytes) always, plus
++ * R0-to-v0 assignment (4 bytes) if big endian.
++ */
++#ifdef __BIG_ENDIAN
++#define JIT_TCALL_SKIP 12
++#else
++#define JIT_TCALL_SKIP 8
++#endif
++
++/* CPU registers holding the callee return value */
++#define JIT_RETURN_REGS	  \
++	(BIT(MIPS_R_V0) | \
++	 BIT(MIPS_R_V1))
++
++/* CPU registers arguments passed to callee directly */
++#define JIT_ARG_REGS      \
++	(BIT(MIPS_R_A0) | \
++	 BIT(MIPS_R_A1) | \
++	 BIT(MIPS_R_A2) | \
++	 BIT(MIPS_R_A3))
++
++/* CPU register arguments passed to callee on stack */
++#define JIT_STACK_REGS    \
++	(BIT(MIPS_R_T0) | \
++	 BIT(MIPS_R_T1) | \
++	 BIT(MIPS_R_T2) | \
++	 BIT(MIPS_R_T3) | \
++	 BIT(MIPS_R_T4) | \
++	 BIT(MIPS_R_T5))
++
++/* Caller-saved CPU registers */
++#define JIT_CALLER_REGS    \
++	(JIT_RETURN_REGS | \
++	 JIT_ARG_REGS    | \
++	 JIT_STACK_REGS)
++
++/* Callee-saved CPU registers */
++#define JIT_CALLEE_REGS   \
++	(BIT(MIPS_R_S0) | \
++	 BIT(MIPS_R_S1) | \
++	 BIT(MIPS_R_S2) | \
++	 BIT(MIPS_R_S3) | \
++	 BIT(MIPS_R_S4) | \
++	 BIT(MIPS_R_S5) | \
++	 BIT(MIPS_R_S6) | \
++	 BIT(MIPS_R_S7) | \
++	 BIT(MIPS_R_GP) | \
++	 BIT(MIPS_R_FP) | \
++	 BIT(MIPS_R_RA))
++
++/*
++ * Mapping of 64-bit eBPF registers to 32-bit native MIPS registers.
++ *
++ * 1) Native register pairs are ordered according to CPU endiannes, following
++ *    the MIPS convention for passing 64-bit arguments and return values.
++ * 2) The eBPF return value, arguments and callee-saved registers are mapped
++ *    to their native MIPS equivalents.
++ * 3) Since the 32 highest bits in the eBPF FP register are always zero,
++ *    only one general-purpose register is actually needed for the mapping.
++ *    We use the fp register for this purpose, and map the highest bits to
++ *    the MIPS register r0 (zero).
++ * 4) We use the MIPS gp and at registers as internal temporary registers
++ *    for constant blinding. The gp register is callee-saved.
++ * 5) One 64-bit temporary register is mapped for use when sign-extending
++ *    immediate operands. MIPS registers t6-t9 are available to the JIT
++ *    for as temporaries when implementing complex 64-bit operations.
++ *
++ * With this scheme all eBPF registers are being mapped to native MIPS
++ * registers without having to use any stack scratch space. The direct
++ * register mapping (2) simplifies the handling of function calls.
++ */
++static const u8 bpf2mips32[][2] = {
++	/* Return value from in-kernel function, and exit value from eBPF */
++	[BPF_REG_0] = {MIPS_R_V1, MIPS_R_V0},
++	/* Arguments from eBPF program to in-kernel function */
++	[BPF_REG_1] = {MIPS_R_A1, MIPS_R_A0},
++	[BPF_REG_2] = {MIPS_R_A3, MIPS_R_A2},
++	/* Remaining arguments, to be passed on the stack per O32 ABI */
++	[BPF_REG_3] = {MIPS_R_T1, MIPS_R_T0},
++	[BPF_REG_4] = {MIPS_R_T3, MIPS_R_T2},
++	[BPF_REG_5] = {MIPS_R_T5, MIPS_R_T4},
++	/* Callee-saved registers that in-kernel function will preserve */
++	[BPF_REG_6] = {MIPS_R_S1, MIPS_R_S0},
++	[BPF_REG_7] = {MIPS_R_S3, MIPS_R_S2},
++	[BPF_REG_8] = {MIPS_R_S5, MIPS_R_S4},
++	[BPF_REG_9] = {MIPS_R_S7, MIPS_R_S6},
++	/* Read-only frame pointer to access the eBPF stack */
++#ifdef __BIG_ENDIAN
++	[BPF_REG_FP] = {MIPS_R_FP, MIPS_R_ZERO},
++#else
++	[BPF_REG_FP] = {MIPS_R_ZERO, MIPS_R_FP},
++#endif
++	/* Temporary register for blinding constants */
++	[BPF_REG_AX] = {MIPS_R_GP, MIPS_R_AT},
++	/* Temporary register for internal JIT use */
++	[JIT_REG_TMP] = {MIPS_R_T7, MIPS_R_T6},
++};
++
++/* Get low CPU register for a 64-bit eBPF register mapping */
++static inline u8 lo(const u8 reg[])
++{
++#ifdef __BIG_ENDIAN
++	return reg[0];
++#else
++	return reg[1];
++#endif
++}
++
++/* Get high CPU register for a 64-bit eBPF register mapping */
++static inline u8 hi(const u8 reg[])
++{
++#ifdef __BIG_ENDIAN
++	return reg[1];
++#else
++	return reg[0];
++#endif
++}
++
++/*
++ * Mark a 64-bit CPU register pair as clobbered, it needs to be
++ * saved/restored by the program if callee-saved.
++ */
++static void clobber_reg64(struct jit_context *ctx, const u8 reg[])
++{
++	clobber_reg(ctx, reg[0]);
++	clobber_reg(ctx, reg[1]);
++}
++
++/* dst = imm (sign-extended) */
++static void emit_mov_se_i64(struct jit_context *ctx, const u8 dst[], s32 imm)
++{
++	emit_mov_i(ctx, lo(dst), imm);
++	if (imm < 0)
++		emit(ctx, addiu, hi(dst), MIPS_R_ZERO, -1);
++	else
++		emit(ctx, move, hi(dst), MIPS_R_ZERO);
++	clobber_reg64(ctx, dst);
++}
++
++/* Zero extension, if verifier does not do it for us  */
++static void emit_zext_ver(struct jit_context *ctx, const u8 dst[])
++{
++	if (!ctx->program->aux->verifier_zext) {
++		emit(ctx, move, hi(dst), MIPS_R_ZERO);
++		clobber_reg(ctx, hi(dst));
++	}
++}
++
++/* Load delay slot, if ISA mandates it */
++static void emit_load_delay(struct jit_context *ctx)
++{
++	if (!cpu_has_mips_2_3_4_5_r)
++		emit(ctx, nop);
++}
++
++/* ALU immediate operation (64-bit) */
++static void emit_alu_i64(struct jit_context *ctx,
++			 const u8 dst[], s32 imm, u8 op)
++{
++	u8 src = MIPS_R_T6;
++
++	/*
++	 * ADD/SUB with all but the max negative imm can be handled by
++	 * inverting the operation and the imm value, saving one insn.
++	 */
++	if (imm > S32_MIN && imm < 0)
++		switch (op) {
++		case BPF_ADD:
++			op = BPF_SUB;
++			imm = -imm;
++			break;
++		case BPF_SUB:
++			op = BPF_ADD;
++			imm = -imm;
++			break;
++		}
++
++	/* Move immediate to temporary register */
++	emit_mov_i(ctx, src, imm);
++
++	switch (op) {
++	/* dst = dst + imm */
++	case BPF_ADD:
++		emit(ctx, addu, lo(dst), lo(dst), src);
++		emit(ctx, sltu, MIPS_R_T9, lo(dst), src);
++		emit(ctx, addu, hi(dst), hi(dst), MIPS_R_T9);
++		if (imm < 0)
++			emit(ctx, addiu, hi(dst), hi(dst), -1);
++		break;
++	/* dst = dst - imm */
++	case BPF_SUB:
++		emit(ctx, sltu, MIPS_R_T9, lo(dst), src);
++		emit(ctx, subu, lo(dst), lo(dst), src);
++		emit(ctx, subu, hi(dst), hi(dst), MIPS_R_T9);
++		if (imm < 0)
++			emit(ctx, addiu, hi(dst), hi(dst), 1);
++		break;
++	/* dst = dst | imm */
++	case BPF_OR:
++		emit(ctx, or, lo(dst), lo(dst), src);
++		if (imm < 0)
++			emit(ctx, addiu, hi(dst), MIPS_R_ZERO, -1);
++		break;
++	/* dst = dst & imm */
++	case BPF_AND:
++		emit(ctx, and, lo(dst), lo(dst), src);
++		if (imm >= 0)
++			emit(ctx, move, hi(dst), MIPS_R_ZERO);
++		break;
++	/* dst = dst ^ imm */
++	case BPF_XOR:
++		emit(ctx, xor, lo(dst), lo(dst), src);
++		if (imm < 0) {
++			emit(ctx, subu, hi(dst), MIPS_R_ZERO, hi(dst));
++			emit(ctx, addiu, hi(dst), hi(dst), -1);
++		}
++		break;
++	}
++	clobber_reg64(ctx, dst);
++}
++
++/* ALU register operation (64-bit) */
++static void emit_alu_r64(struct jit_context *ctx,
++			 const u8 dst[], const u8 src[], u8 op)
++{
++	switch (BPF_OP(op)) {
++	/* dst = dst + src */
++	case BPF_ADD:
++		if (src == dst) {
++			emit(ctx, srl, MIPS_R_T9, lo(dst), 31);
++			emit(ctx, addu, lo(dst), lo(dst), lo(dst));
++		} else {
++			emit(ctx, addu, lo(dst), lo(dst), lo(src));
++			emit(ctx, sltu, MIPS_R_T9, lo(dst), lo(src));
++		}
++		emit(ctx, addu, hi(dst), hi(dst), hi(src));
++		emit(ctx, addu, hi(dst), hi(dst), MIPS_R_T9);
++		break;
++	/* dst = dst - src */
++	case BPF_SUB:
++		emit(ctx, sltu, MIPS_R_T9, lo(dst), lo(src));
++		emit(ctx, subu, lo(dst), lo(dst), lo(src));
++		emit(ctx, subu, hi(dst), hi(dst), hi(src));
++		emit(ctx, subu, hi(dst), hi(dst), MIPS_R_T9);
++		break;
++	/* dst = dst | src */
++	case BPF_OR:
++		emit(ctx, or, lo(dst), lo(dst), lo(src));
++		emit(ctx, or, hi(dst), hi(dst), hi(src));
++		break;
++	/* dst = dst & src */
++	case BPF_AND:
++		emit(ctx, and, lo(dst), lo(dst), lo(src));
++		emit(ctx, and, hi(dst), hi(dst), hi(src));
++		break;
++	/* dst = dst ^ src */
++	case BPF_XOR:
++		emit(ctx, xor, lo(dst), lo(dst), lo(src));
++		emit(ctx, xor, hi(dst), hi(dst), hi(src));
++		break;
++	}
++	clobber_reg64(ctx, dst);
++}
++
++/* ALU invert (64-bit) */
++static void emit_neg_i64(struct jit_context *ctx, const u8 dst[])
++{
++	emit(ctx, sltu, MIPS_R_T9, MIPS_R_ZERO, lo(dst));
++	emit(ctx, subu, lo(dst), MIPS_R_ZERO, lo(dst));
++	emit(ctx, subu, hi(dst), MIPS_R_ZERO, hi(dst));
++	emit(ctx, subu, hi(dst), hi(dst), MIPS_R_T9);
++
++	clobber_reg64(ctx, dst);
++}
++
++/* ALU shift immediate (64-bit) */
++static void emit_shift_i64(struct jit_context *ctx,
++			   const u8 dst[], u32 imm, u8 op)
++{
++	switch (BPF_OP(op)) {
++	/* dst = dst << imm */
++	case BPF_LSH:
++		if (imm < 32) {
++			emit(ctx, srl, MIPS_R_T9, lo(dst), 32 - imm);
++			emit(ctx, sll, lo(dst), lo(dst), imm);
++			emit(ctx, sll, hi(dst), hi(dst), imm);
++			emit(ctx, or, hi(dst), hi(dst), MIPS_R_T9);
++		} else {
++			emit(ctx, sll, hi(dst), lo(dst), imm - 32);
++			emit(ctx, move, lo(dst), MIPS_R_ZERO);
++		}
++		break;
++	/* dst = dst >> imm */
++	case BPF_RSH:
++		if (imm < 32) {
++			emit(ctx, sll, MIPS_R_T9, hi(dst), 32 - imm);
++			emit(ctx, srl, lo(dst), lo(dst), imm);
++			emit(ctx, srl, hi(dst), hi(dst), imm);
++			emit(ctx, or, lo(dst), lo(dst), MIPS_R_T9);
++		} else {
++			emit(ctx, srl, lo(dst), hi(dst), imm - 32);
++			emit(ctx, move, hi(dst), MIPS_R_ZERO);
++		}
++		break;
++	/* dst = dst >> imm (arithmetic) */
++	case BPF_ARSH:
++		if (imm < 32) {
++			emit(ctx, sll, MIPS_R_T9, hi(dst), 32 - imm);
++			emit(ctx, srl, lo(dst), lo(dst), imm);
++			emit(ctx, sra, hi(dst), hi(dst), imm);
++			emit(ctx, or, lo(dst), lo(dst), MIPS_R_T9);
++		} else {
++			emit(ctx, sra, lo(dst), hi(dst), imm - 32);
++			emit(ctx, sra, hi(dst), hi(dst), 31);
++		}
++		break;
++	}
++	clobber_reg64(ctx, dst);
++}
++
++/* ALU shift register (64-bit) */
++static void emit_shift_r64(struct jit_context *ctx,
++			   const u8 dst[], u8 src, u8 op)
++{
++	u8 t1 = MIPS_R_T8;
++	u8 t2 = MIPS_R_T9;
++
++	emit(ctx, andi, t1, src, 32);              /* t1 = src & 32          */
++	emit(ctx, beqz, t1, 16);                   /* PC += 16 if t1 == 0    */
++	emit(ctx, nor, t2, src, MIPS_R_ZERO);      /* t2 = ~src (delay slot) */
++
++	switch (BPF_OP(op)) {
++	/* dst = dst << src */
++	case BPF_LSH:
++		/* Next: shift >= 32 */
++		emit(ctx, sllv, hi(dst), lo(dst), src);    /* dh = dl << src */
++		emit(ctx, move, lo(dst), MIPS_R_ZERO);     /* dl = 0         */
++		emit(ctx, b, 20);                          /* PC += 20       */
++		/* +16: shift < 32 */
++		emit(ctx, srl, t1, lo(dst), 1);            /* t1 = dl >> 1   */
++		emit(ctx, srlv, t1, t1, t2);               /* t1 = t1 >> t2  */
++		emit(ctx, sllv, lo(dst), lo(dst), src);    /* dl = dl << src */
++		emit(ctx, sllv, hi(dst), hi(dst), src);    /* dh = dh << src */
++		emit(ctx, or, hi(dst), hi(dst), t1);       /* dh = dh | t1   */
++		break;
++	/* dst = dst >> src */
++	case BPF_RSH:
++		/* Next: shift >= 32 */
++		emit(ctx, srlv, lo(dst), hi(dst), src);    /* dl = dh >> src */
++		emit(ctx, move, hi(dst), MIPS_R_ZERO);     /* dh = 0         */
++		emit(ctx, b, 20);                          /* PC += 20       */
++		/* +16: shift < 32 */
++		emit(ctx, sll, t1, hi(dst), 1);            /* t1 = dl << 1   */
++		emit(ctx, sllv, t1, t1, t2);               /* t1 = t1 << t2  */
++		emit(ctx, srlv, lo(dst), lo(dst), src);    /* dl = dl >> src */
++		emit(ctx, srlv, hi(dst), hi(dst), src);    /* dh = dh >> src */
++		emit(ctx, or, lo(dst), lo(dst), t1);       /* dl = dl | t1   */
++		break;
++	/* dst = dst >> src (arithmetic) */
++	case BPF_ARSH:
++		/* Next: shift >= 32 */
++		emit(ctx, srav, lo(dst), hi(dst), src);   /* dl = dh >>a src */
++		emit(ctx, sra, hi(dst), hi(dst), 31);     /* dh = dh >>a 31  */
++		emit(ctx, b, 20);                         /* PC += 20        */
++		/* +16: shift < 32 */
++		emit(ctx, sll, t1, hi(dst), 1);           /* t1 = dl << 1    */
++		emit(ctx, sllv, t1, t1, t2);              /* t1 = t1 << t2   */
++		emit(ctx, srlv, lo(dst), lo(dst), src);   /* dl = dl >>a src */
++		emit(ctx, srav, hi(dst), hi(dst), src);   /* dh = dh >> src  */
++		emit(ctx, or, lo(dst), lo(dst), t1);      /* dl = dl | t1    */
++		break;
++	}
++
++	/* +20: Done */
++	clobber_reg64(ctx, dst);
++}
++
++/* ALU mul immediate (64x32-bit) */
++static void emit_mul_i64(struct jit_context *ctx, const u8 dst[], s32 imm)
++{
++	u8 src = MIPS_R_T6;
++	u8 tmp = MIPS_R_T9;
++
++	switch (imm) {
++	/* dst = dst * 1 is a no-op */
++	case 1:
++		break;
++	/* dst = dst * -1 */
++	case -1:
++		emit_neg_i64(ctx, dst);
++		break;
++	case 0:
++		emit_mov_r(ctx, lo(dst), MIPS_R_ZERO);
++		emit_mov_r(ctx, hi(dst), MIPS_R_ZERO);
++		break;
++	/* Full 64x32 multiply */
++	default:
++		/* hi(dst) = hi(dst) * src(imm) */
++		emit_mov_i(ctx, src, imm);
++		if (cpu_has_mips32r1 || cpu_has_mips32r6) {
++			emit(ctx, mul, hi(dst), hi(dst), src);
++		} else {
++			emit(ctx, multu, hi(dst), src);
++			emit(ctx, mflo, hi(dst));
++		}
++
++		/* hi(dst) = hi(dst) - lo(dst) */
++		if (imm < 0)
++			emit(ctx, subu, hi(dst), hi(dst), lo(dst));
++
++		/* tmp = lo(dst) * src(imm) >> 32 */
++		/* lo(dst) = lo(dst) * src(imm) */
++		if (cpu_has_mips32r6) {
++			emit(ctx, muhu, tmp, lo(dst), src);
++			emit(ctx, mulu, lo(dst), lo(dst), src);
++		} else {
++			emit(ctx, multu, lo(dst), src);
++			emit(ctx, mflo, lo(dst));
++			emit(ctx, mfhi, tmp);
++		}
++
++		/* hi(dst) += tmp */
++		emit(ctx, addu, hi(dst), hi(dst), tmp);
++		clobber_reg64(ctx, dst);
++		break;
++	}
++}
++
++/* ALU mul register (64x64-bit) */
++static void emit_mul_r64(struct jit_context *ctx,
++			 const u8 dst[], const u8 src[])
++{
++	u8 acc = MIPS_R_T8;
++	u8 tmp = MIPS_R_T9;
++
++	/* acc = hi(dst) * lo(src) */
++	if (cpu_has_mips32r1 || cpu_has_mips32r6) {
++		emit(ctx, mul, acc, hi(dst), lo(src));
++	} else {
++		emit(ctx, multu, hi(dst), lo(src));
++		emit(ctx, mflo, acc);
++	}
++
++	/* tmp = lo(dst) * hi(src) */
++	if (cpu_has_mips32r1 || cpu_has_mips32r6) {
++		emit(ctx, mul, tmp, lo(dst), hi(src));
++	} else {
++		emit(ctx, multu, lo(dst), hi(src));
++		emit(ctx, mflo, tmp);
++	}
++
++	/* acc += tmp */
++	emit(ctx, addu, acc, acc, tmp);
++
++	/* tmp = lo(dst) * lo(src) >> 32 */
++	/* lo(dst) = lo(dst) * lo(src) */
++	if (cpu_has_mips32r6) {
++		emit(ctx, muhu, tmp, lo(dst), lo(src));
++		emit(ctx, mulu, lo(dst), lo(dst), lo(src));
++	} else {
++		emit(ctx, multu, lo(dst), lo(src));
++		emit(ctx, mflo, lo(dst));
++		emit(ctx, mfhi, tmp);
++	}
++
++	/* hi(dst) = acc + tmp */
++	emit(ctx, addu, hi(dst), acc, tmp);
++	clobber_reg64(ctx, dst);
++}
++
++/* Helper function for 64-bit modulo */
++static u64 jit_mod64(u64 a, u64 b)
++{
++	u64 rem;
++
++	div64_u64_rem(a, b, &rem);
++	return rem;
++}
++
++/* ALU div/mod register (64-bit) */
++static void emit_divmod_r64(struct jit_context *ctx,
++			    const u8 dst[], const u8 src[], u8 op)
++{
++	const u8 *r0 = bpf2mips32[BPF_REG_0]; /* Mapped to v0-v1 */
++	const u8 *r1 = bpf2mips32[BPF_REG_1]; /* Mapped to a0-a1 */
++	const u8 *r2 = bpf2mips32[BPF_REG_2]; /* Mapped to a2-a3 */
++	int exclude, k;
++	u32 addr = 0;
++
++	/* Push caller-saved registers on stack */
++	push_regs(ctx, ctx->clobbered & JIT_CALLER_REGS,
++		  0, JIT_RESERVED_STACK);
++
++	/* Put 64-bit arguments 1 and 2 in registers a0-a3 */
++	for (k = 0; k < 2; k++) {
++		emit(ctx, move, MIPS_R_T9, src[k]);
++		emit(ctx, move, r1[k], dst[k]);
++		emit(ctx, move, r2[k], MIPS_R_T9);
++	}
++
++	/* Emit function call */
++	switch (BPF_OP(op)) {
++	/* dst = dst / src */
++	case BPF_DIV:
++		addr = (u32)&div64_u64;
++		break;
++	/* dst = dst % src */
++	case BPF_MOD:
++		addr = (u32)&jit_mod64;
++		break;
++	}
++	emit_mov_i(ctx, MIPS_R_T9, addr);
++	emit(ctx, jalr, MIPS_R_RA, MIPS_R_T9);
++	emit(ctx, nop); /* Delay slot */
++
++	/* Store the 64-bit result in dst */
++	emit(ctx, move, dst[0], r0[0]);
++	emit(ctx, move, dst[1], r0[1]);
++
++	/* Restore caller-saved registers, excluding the computed result */
++	exclude = BIT(lo(dst)) | BIT(hi(dst));
++	pop_regs(ctx, ctx->clobbered & JIT_CALLER_REGS,
++		 exclude, JIT_RESERVED_STACK);
++	emit_load_delay(ctx);
++
++	clobber_reg64(ctx, dst);
++	clobber_reg(ctx, MIPS_R_V0);
++	clobber_reg(ctx, MIPS_R_V1);
++	clobber_reg(ctx, MIPS_R_RA);
++}
++
++/* Swap bytes in a register word */
++static void emit_swap8_r(struct jit_context *ctx, u8 dst, u8 src, u8 mask)
++{
++	u8 tmp = MIPS_R_T9;
++
++	emit(ctx, and, tmp, src, mask); /* tmp = src & 0x00ff00ff */
++	emit(ctx, sll, tmp, tmp, 8);    /* tmp = tmp << 8         */
++	emit(ctx, srl, dst, src, 8);    /* dst = src >> 8         */
++	emit(ctx, and, dst, dst, mask); /* dst = dst & 0x00ff00ff */
++	emit(ctx, or,  dst, dst, tmp);  /* dst = dst | tmp        */
++}
++
++/* Swap half words in a register word */
++static void emit_swap16_r(struct jit_context *ctx, u8 dst, u8 src)
++{
++	u8 tmp = MIPS_R_T9;
++
++	emit(ctx, sll, tmp, src, 16);  /* tmp = src << 16 */
++	emit(ctx, srl, dst, src, 16);  /* dst = src >> 16 */
++	emit(ctx, or,  dst, dst, tmp); /* dst = dst | tmp */
++}
++
++/* Swap bytes and truncate a register double word, word or half word */
++static void emit_bswap_r64(struct jit_context *ctx, const u8 dst[], u32 width)
++{
++	u8 tmp = MIPS_R_T8;
++
++	switch (width) {
++	/* Swap bytes in a double word */
++	case 64:
++		if (cpu_has_mips32r2 || cpu_has_mips32r6) {
++			emit(ctx, rotr, tmp, hi(dst), 16);
++			emit(ctx, rotr, hi(dst), lo(dst), 16);
++			emit(ctx, wsbh, lo(dst), tmp);
++			emit(ctx, wsbh, hi(dst), hi(dst));
++		} else {
++			emit_swap16_r(ctx, tmp, lo(dst));
++			emit_swap16_r(ctx, lo(dst), hi(dst));
++			emit(ctx, move, hi(dst), tmp);
++
++			emit(ctx, lui, tmp, 0xff);      /* tmp = 0x00ff0000 */
++			emit(ctx, ori, tmp, tmp, 0xff); /* tmp = 0x00ff00ff */
++			emit_swap8_r(ctx, lo(dst), lo(dst), tmp);
++			emit_swap8_r(ctx, hi(dst), hi(dst), tmp);
++		}
++		break;
++	/* Swap bytes in a word */
++	/* Swap bytes in a half word */
++	case 32:
++	case 16:
++		emit_bswap_r(ctx, lo(dst), width);
++		emit(ctx, move, hi(dst), MIPS_R_ZERO);
++		break;
++	}
++	clobber_reg64(ctx, dst);
++}
++
++/* Truncate a register double word, word or half word */
++static void emit_trunc_r64(struct jit_context *ctx, const u8 dst[], u32 width)
++{
++	switch (width) {
++	case 64:
++		break;
++	/* Zero-extend a word */
++	case 32:
++		emit(ctx, move, hi(dst), MIPS_R_ZERO);
++		clobber_reg(ctx, hi(dst));
++		break;
++	/* Zero-extend a half word */
++	case 16:
++		emit(ctx, move, hi(dst), MIPS_R_ZERO);
++		emit(ctx, andi, lo(dst), lo(dst), 0xffff);
++		clobber_reg64(ctx, dst);
++		break;
++	}
++}
++
++/* Load operation: dst = *(size*)(src + off) */
++static void emit_ldx(struct jit_context *ctx,
++		     const u8 dst[], u8 src, s16 off, u8 size)
++{
++	switch (size) {
++	/* Load a byte */
++	case BPF_B:
++		emit(ctx, lbu, lo(dst), off, src);
++		emit(ctx, move, hi(dst), MIPS_R_ZERO);
++		break;
++	/* Load a half word */
++	case BPF_H:
++		emit(ctx, lhu, lo(dst), off, src);
++		emit(ctx, move, hi(dst), MIPS_R_ZERO);
++		break;
++	/* Load a word */
++	case BPF_W:
++		emit(ctx, lw, lo(dst), off, src);
++		emit(ctx, move, hi(dst), MIPS_R_ZERO);
++		break;
++	/* Load a double word */
++	case BPF_DW:
++		if (dst[1] == src) {
++			emit(ctx, lw, dst[0], off + 4, src);
++			emit(ctx, lw, dst[1], off, src);
++		} else {
++			emit(ctx, lw, dst[1], off, src);
++			emit(ctx, lw, dst[0], off + 4, src);
++		}
++		emit_load_delay(ctx);
++		break;
++	}
++	clobber_reg64(ctx, dst);
++}
++
++/* Store operation: *(size *)(dst + off) = src */
++static void emit_stx(struct jit_context *ctx,
++		     const u8 dst, const u8 src[], s16 off, u8 size)
++{
++	switch (size) {
++	/* Store a byte */
++	case BPF_B:
++		emit(ctx, sb, lo(src), off, dst);
++		break;
++	/* Store a half word */
++	case BPF_H:
++		emit(ctx, sh, lo(src), off, dst);
++		break;
++	/* Store a word */
++	case BPF_W:
++		emit(ctx, sw, lo(src), off, dst);
++		break;
++	/* Store a double word */
++	case BPF_DW:
++		emit(ctx, sw, src[1], off, dst);
++		emit(ctx, sw, src[0], off + 4, dst);
++		break;
++	}
++}
++
++/* Atomic read-modify-write (32-bit, non-ll/sc fallback) */
++static void emit_atomic_r32(struct jit_context *ctx,
++			    u8 dst, u8 src, s16 off, u8 code)
++{
++	u32 exclude = 0;
++	u32 addr = 0;
++
++	/* Push caller-saved registers on stack */
++	push_regs(ctx, ctx->clobbered & JIT_CALLER_REGS,
++		  0, JIT_RESERVED_STACK);
++	/*
++	 * Argument 1: dst+off if xchg, otherwise src, passed in register a0
++	 * Argument 2: src if xchg, othersize dst+off, passed in register a1
++	 */
++	emit(ctx, move, MIPS_R_T9, dst);
++	emit(ctx, move, MIPS_R_A0, src);
++	emit(ctx, addiu, MIPS_R_A1, MIPS_R_T9, off);
++
++	/* Emit function call */
++	switch (code) {
++	case BPF_ADD:
++		addr = (u32)&atomic_add;
++		break;
++	case BPF_SUB:
++		addr = (u32)&atomic_sub;
++		break;
++	case BPF_OR:
++		addr = (u32)&atomic_or;
++		break;
++	case BPF_AND:
++		addr = (u32)&atomic_and;
++		break;
++	case BPF_XOR:
++		addr = (u32)&atomic_xor;
++		break;
++	}
++	emit_mov_i(ctx, MIPS_R_T9, addr);
++	emit(ctx, jalr, MIPS_R_RA, MIPS_R_T9);
++	emit(ctx, nop); /* Delay slot */
++
++	/* Restore caller-saved registers, except any fetched value */
++	pop_regs(ctx, ctx->clobbered & JIT_CALLER_REGS,
++		 exclude, JIT_RESERVED_STACK);
++	emit_load_delay(ctx);
++	clobber_reg(ctx, MIPS_R_RA);
++}
++
++/* Atomic read-modify-write (64-bit) */
++static void emit_atomic_r64(struct jit_context *ctx,
++			    u8 dst, const u8 src[], s16 off, u8 code)
++{
++	const u8 *r1 = bpf2mips32[BPF_REG_1]; /* Mapped to a0-a1 */
++	u32 exclude = 0;
++	u32 addr = 0;
++
++	/* Push caller-saved registers on stack */
++	push_regs(ctx, ctx->clobbered & JIT_CALLER_REGS,
++		  0, JIT_RESERVED_STACK);
++	/*
++	 * Argument 1: 64-bit src, passed in registers a0-a1
++	 * Argument 2: 32-bit dst+off, passed in register a2
++	 */
++	emit(ctx, move, MIPS_R_T9, dst);
++	emit(ctx, move, r1[0], src[0]);
++	emit(ctx, move, r1[1], src[1]);
++	emit(ctx, addiu, MIPS_R_A2, MIPS_R_T9, off);
++
++	/* Emit function call */
++	switch (code) {
++	case BPF_ADD:
++		addr = (u32)&atomic64_add;
++		break;
++	case BPF_SUB:
++		addr = (u32)&atomic64_sub;
++		break;
++	case BPF_OR:
++		addr = (u32)&atomic64_or;
++		break;
++	case BPF_AND:
++		addr = (u32)&atomic64_and;
++		break;
++	case BPF_XOR:
++		addr = (u32)&atomic64_xor;
++		break;
++	}
++	emit_mov_i(ctx, MIPS_R_T9, addr);
++	emit(ctx, jalr, MIPS_R_RA, MIPS_R_T9);
++	emit(ctx, nop); /* Delay slot */
++
++	/* Restore caller-saved registers, except any fetched value */
++	pop_regs(ctx, ctx->clobbered & JIT_CALLER_REGS,
++		 exclude, JIT_RESERVED_STACK);
++	emit_load_delay(ctx);
++	clobber_reg(ctx, MIPS_R_RA);
++}
++
++/*
++ * Conditional movz or an emulated equivalent.
++ * Note that the rs register may be modified.
++ */
++static void emit_movz_r(struct jit_context *ctx, u8 rd, u8 rs, u8 rt)
++{
++	if (cpu_has_mips_2) {
++		emit(ctx, movz, rd, rs, rt);           /* rd = rt ? rd : rs  */
++	} else if (cpu_has_mips32r6) {
++		if (rs != MIPS_R_ZERO)
++			emit(ctx, seleqz, rs, rs, rt); /* rs = 0 if rt == 0  */
++		emit(ctx, selnez, rd, rd, rt);         /* rd = 0 if rt != 0  */
++		if (rs != MIPS_R_ZERO)
++			emit(ctx, or, rd, rd, rs);     /* rd = rd | rs       */
++	} else {
++		emit(ctx, bnez, rt, 8);                /* PC += 8 if rd != 0 */
++		emit(ctx, nop);                        /* +0: delay slot     */
++		emit(ctx, or, rd, rs, MIPS_R_ZERO);    /* +4: rd = rs        */
++	}
++	clobber_reg(ctx, rd);
++	clobber_reg(ctx, rs);
++}
++
++/*
++ * Conditional movn or an emulated equivalent.
++ * Note that the rs register may be modified.
++ */
++static void emit_movn_r(struct jit_context *ctx, u8 rd, u8 rs, u8 rt)
++{
++	if (cpu_has_mips_2) {
++		emit(ctx, movn, rd, rs, rt);           /* rd = rt ? rs : rd  */
++	} else if (cpu_has_mips32r6) {
++		if (rs != MIPS_R_ZERO)
++			emit(ctx, selnez, rs, rs, rt); /* rs = 0 if rt == 0  */
++		emit(ctx, seleqz, rd, rd, rt);         /* rd = 0 if rt != 0  */
++		if (rs != MIPS_R_ZERO)
++			emit(ctx, or, rd, rd, rs);     /* rd = rd | rs       */
++	} else {
++		emit(ctx, beqz, rt, 8);                /* PC += 8 if rd == 0 */
++		emit(ctx, nop);                        /* +0: delay slot     */
++		emit(ctx, or, rd, rs, MIPS_R_ZERO);    /* +4: rd = rs        */
++	}
++	clobber_reg(ctx, rd);
++	clobber_reg(ctx, rs);
++}
++
++/* Emulation of 64-bit sltiu rd, rs, imm, where imm may be S32_MAX + 1 */
++static void emit_sltiu_r64(struct jit_context *ctx, u8 rd,
++			   const u8 rs[], s64 imm)
++{
++	u8 tmp = MIPS_R_T9;
++
++	if (imm < 0) {
++		emit_mov_i(ctx, rd, imm);                 /* rd = imm        */
++		emit(ctx, sltu, rd, lo(rs), rd);          /* rd = rsl < rd   */
++		emit(ctx, sltiu, tmp, hi(rs), -1);        /* tmp = rsh < ~0U */
++		emit(ctx, or, rd, rd, tmp);               /* rd = rd | tmp   */
++	} else { /* imm >= 0 */
++		if (imm > 0x7fff) {
++			emit_mov_i(ctx, rd, (s32)imm);     /* rd = imm       */
++			emit(ctx, sltu, rd, lo(rs), rd);   /* rd = rsl < rd  */
++		} else {
++			emit(ctx, sltiu, rd, lo(rs), imm); /* rd = rsl < imm */
++		}
++		emit_movn_r(ctx, rd, MIPS_R_ZERO, hi(rs)); /* rd = 0 if rsh  */
++	}
++}
++
++/* Emulation of 64-bit sltu rd, rs, rt */
++static void emit_sltu_r64(struct jit_context *ctx, u8 rd,
++			  const u8 rs[], const u8 rt[])
++{
++	u8 tmp = MIPS_R_T9;
++
++	emit(ctx, sltu, rd, lo(rs), lo(rt));           /* rd = rsl < rtl     */
++	emit(ctx, subu, tmp, hi(rs), hi(rt));          /* tmp = rsh - rth    */
++	emit_movn_r(ctx, rd, MIPS_R_ZERO, tmp);        /* rd = 0 if tmp != 0 */
++	emit(ctx, sltu, tmp, hi(rs), hi(rt));          /* tmp = rsh < rth    */
++	emit(ctx, or, rd, rd, tmp);                    /* rd = rd | tmp      */
++}
++
++/* Emulation of 64-bit slti rd, rs, imm, where imm may be S32_MAX + 1 */
++static void emit_slti_r64(struct jit_context *ctx, u8 rd,
++			  const u8 rs[], s64 imm)
++{
++	u8 t1 = MIPS_R_T8;
++	u8 t2 = MIPS_R_T9;
++	u8 cmp;
++
++	/*
++	 * if ((rs < 0) ^ (imm < 0)) t1 = imm >u rsl
++	 * else                      t1 = rsl <u imm
++	 */
++	emit_mov_i(ctx, rd, (s32)imm);
++	emit(ctx, sltu, t1, lo(rs), rd);               /* t1 = rsl <u imm   */
++	emit(ctx, sltu, t2, rd, lo(rs));               /* t2 = imm <u rsl   */
++	emit(ctx, srl, rd, hi(rs), 31);                /* rd = rsh >> 31    */
++	if (imm < 0)
++		emit_movz_r(ctx, t1, t2, rd);          /* t1 = rd ? t1 : t2 */
++	else
++		emit_movn_r(ctx, t1, t2, rd);          /* t1 = rd ? t2 : t1 */
++	/*
++	 * if ((imm < 0 && rsh != 0xffffffff) ||
++	 *     (imm >= 0 && rsh != 0))
++	 *      t1 = 0
++	 */
++	if (imm < 0) {
++		emit(ctx, addiu, rd, hi(rs), 1);       /* rd = rsh + 1 */
++		cmp = rd;
++	} else { /* imm >= 0 */
++		cmp = hi(rs);
++	}
++	emit_movn_r(ctx, t1, MIPS_R_ZERO, cmp);        /* t1 = 0 if cmp != 0 */
++
++	/*
++	 * if (imm < 0) rd = rsh < -1
++	 * else         rd = rsh != 0
++	 * rd = rd | t1
++	 */
++	emit(ctx, slti, rd, hi(rs), imm < 0 ? -1 : 0); /* rd = rsh < hi(imm) */
++	emit(ctx, or, rd, rd, t1);                     /* rd = rd | t1       */
++}
++
++/* Emulation of 64-bit(slt rd, rs, rt) */
++static void emit_slt_r64(struct jit_context *ctx, u8 rd,
++			 const u8 rs[], const u8 rt[])
++{
++	u8 t1 = MIPS_R_T7;
++	u8 t2 = MIPS_R_T8;
++	u8 t3 = MIPS_R_T9;
++
++	/*
++	 * if ((rs < 0) ^ (rt < 0)) t1 = rtl <u rsl
++	 * else                     t1 = rsl <u rtl
++	 * if (rsh == rth)          t1 = 0
++	 */
++	emit(ctx, sltu, t1, lo(rs), lo(rt));           /* t1 = rsl <u rtl   */
++	emit(ctx, sltu, t2, lo(rt), lo(rs));           /* t2 = rtl <u rsl   */
++	emit(ctx, xor, t3, hi(rs), hi(rt));            /* t3 = rlh ^ rth    */
++	emit(ctx, srl, rd, t3, 31);                    /* rd = t3 >> 31     */
++	emit_movn_r(ctx, t1, t2, rd);                  /* t1 = rd ? t2 : t1 */
++	emit_movn_r(ctx, t1, MIPS_R_ZERO, t3);         /* t1 = 0 if t3 != 0 */
++
++	/* rd = (rsh < rth) | t1 */
++	emit(ctx, slt, rd, hi(rs), hi(rt));            /* rd = rsh <s rth   */
++	emit(ctx, or, rd, rd, t1);                     /* rd = rd | t1      */
++}
++
++/* Jump immediate (64-bit) */
++static void emit_jmp_i64(struct jit_context *ctx,
++			 const u8 dst[], s32 imm, s32 off, u8 op)
++{
++	u8 tmp = MIPS_R_T6;
++
++	switch (op) {
++	/* No-op, used internally for branch optimization */
++	case JIT_JNOP:
++		break;
++	/* PC += off if dst == imm */
++	/* PC += off if dst != imm */
++	case BPF_JEQ:
++	case BPF_JNE:
++		if (imm >= -0x7fff && imm <= 0x8000) {
++			emit(ctx, addiu, tmp, lo(dst), -imm);
++		} else if ((u32)imm <= 0xffff) {
++			emit(ctx, xori, tmp, lo(dst), imm);
++		} else {       /* Register fallback */
++			emit_mov_i(ctx, tmp, imm);
++			emit(ctx, xor, tmp, lo(dst), tmp);
++		}
++		if (imm < 0) { /* Compare sign extension */
++			emit(ctx, addu, MIPS_R_T9, hi(dst), 1);
++			emit(ctx, or, tmp, tmp, MIPS_R_T9);
++		} else {       /* Compare zero extension */
++			emit(ctx, or, tmp, tmp, hi(dst));
++		}
++		if (op == BPF_JEQ)
++			emit(ctx, beqz, tmp, off);
++		else   /* BPF_JNE */
++			emit(ctx, bnez, tmp, off);
++		break;
++	/* PC += off if dst & imm */
++	/* PC += off if (dst & imm) == 0 (not in BPF, used for long jumps) */
++	case BPF_JSET:
++	case JIT_JNSET:
++		if ((u32)imm <= 0xffff) {
++			emit(ctx, andi, tmp, lo(dst), imm);
++		} else {     /* Register fallback */
++			emit_mov_i(ctx, tmp, imm);
++			emit(ctx, and, tmp, lo(dst), tmp);
++		}
++		if (imm < 0) /* Sign-extension pulls in high word */
++			emit(ctx, or, tmp, tmp, hi(dst));
++		if (op == BPF_JSET)
++			emit(ctx, bnez, tmp, off);
++		else   /* JIT_JNSET */
++			emit(ctx, beqz, tmp, off);
++		break;
++	/* PC += off if dst > imm */
++	case BPF_JGT:
++		emit_sltiu_r64(ctx, tmp, dst, (s64)imm + 1);
++		emit(ctx, beqz, tmp, off);
++		break;
++	/* PC += off if dst >= imm */
++	case BPF_JGE:
++		emit_sltiu_r64(ctx, tmp, dst, imm);
++		emit(ctx, beqz, tmp, off);
++		break;
++	/* PC += off if dst < imm */
++	case BPF_JLT:
++		emit_sltiu_r64(ctx, tmp, dst, imm);
++		emit(ctx, bnez, tmp, off);
++		break;
++	/* PC += off if dst <= imm */
++	case BPF_JLE:
++		emit_sltiu_r64(ctx, tmp, dst, (s64)imm + 1);
++		emit(ctx, bnez, tmp, off);
++		break;
++	/* PC += off if dst > imm (signed) */
++	case BPF_JSGT:
++		emit_slti_r64(ctx, tmp, dst, (s64)imm + 1);
++		emit(ctx, beqz, tmp, off);
++		break;
++	/* PC += off if dst >= imm (signed) */
++	case BPF_JSGE:
++		emit_slti_r64(ctx, tmp, dst, imm);
++		emit(ctx, beqz, tmp, off);
++		break;
++	/* PC += off if dst < imm (signed) */
++	case BPF_JSLT:
++		emit_slti_r64(ctx, tmp, dst, imm);
++		emit(ctx, bnez, tmp, off);
++		break;
++	/* PC += off if dst <= imm (signed) */
++	case BPF_JSLE:
++		emit_slti_r64(ctx, tmp, dst, (s64)imm + 1);
++		emit(ctx, bnez, tmp, off);
++		break;
++	}
++}
++
++/* Jump register (64-bit) */
++static void emit_jmp_r64(struct jit_context *ctx,
++			 const u8 dst[], const u8 src[], s32 off, u8 op)
++{
++	u8 t1 = MIPS_R_T6;
++	u8 t2 = MIPS_R_T7;
++
++	switch (op) {
++	/* No-op, used internally for branch optimization */
++	case JIT_JNOP:
++		break;
++	/* PC += off if dst == src */
++	/* PC += off if dst != src */
++	case BPF_JEQ:
++	case BPF_JNE:
++		emit(ctx, subu, t1, lo(dst), lo(src));
++		emit(ctx, subu, t2, hi(dst), hi(src));
++		emit(ctx, or, t1, t1, t2);
++		if (op == BPF_JEQ)
++			emit(ctx, beqz, t1, off);
++		else   /* BPF_JNE */
++			emit(ctx, bnez, t1, off);
++		break;
++	/* PC += off if dst & src */
++	/* PC += off if (dst & imm) == 0 (not in BPF, used for long jumps) */
++	case BPF_JSET:
++	case JIT_JNSET:
++		emit(ctx, and, t1, lo(dst), lo(src));
++		emit(ctx, and, t2, hi(dst), hi(src));
++		emit(ctx, or, t1, t1, t2);
++		if (op == BPF_JSET)
++			emit(ctx, bnez, t1, off);
++		else   /* JIT_JNSET */
++			emit(ctx, beqz, t1, off);
++		break;
++	/* PC += off if dst > src */
++	case BPF_JGT:
++		emit_sltu_r64(ctx, t1, src, dst);
++		emit(ctx, bnez, t1, off);
++		break;
++	/* PC += off if dst >= src */
++	case BPF_JGE:
++		emit_sltu_r64(ctx, t1, dst, src);
++		emit(ctx, beqz, t1, off);
++		break;
++	/* PC += off if dst < src */
++	case BPF_JLT:
++		emit_sltu_r64(ctx, t1, dst, src);
++		emit(ctx, bnez, t1, off);
++		break;
++	/* PC += off if dst <= src */
++	case BPF_JLE:
++		emit_sltu_r64(ctx, t1, src, dst);
++		emit(ctx, beqz, t1, off);
++		break;
++	/* PC += off if dst > src (signed) */
++	case BPF_JSGT:
++		emit_slt_r64(ctx, t1, src, dst);
++		emit(ctx, bnez, t1, off);
++		break;
++	/* PC += off if dst >= src (signed) */
++	case BPF_JSGE:
++		emit_slt_r64(ctx, t1, dst, src);
++		emit(ctx, beqz, t1, off);
++		break;
++	/* PC += off if dst < src (signed) */
++	case BPF_JSLT:
++		emit_slt_r64(ctx, t1, dst, src);
++		emit(ctx, bnez, t1, off);
++		break;
++	/* PC += off if dst <= src (signed) */
++	case BPF_JSLE:
++		emit_slt_r64(ctx, t1, src, dst);
++		emit(ctx, beqz, t1, off);
++		break;
++	}
++}
++
++/* Function call */
++static int emit_call(struct jit_context *ctx, const struct bpf_insn *insn)
++{
++	bool fixed;
++	u64 addr;
++
++	/* Decode the call address */
++	if (bpf_jit_get_func_addr(ctx->program, insn, false,
++				  &addr, &fixed) < 0)
++		return -1;
++	if (!fixed)
++		return -1;
++
++	/* Push stack arguments */
++	push_regs(ctx, JIT_STACK_REGS, 0, JIT_RESERVED_STACK);
++
++	/* Emit function call */
++	emit_mov_i(ctx, MIPS_R_T9, addr);
++	emit(ctx, jalr, MIPS_R_RA, MIPS_R_T9);
++	emit(ctx, nop); /* Delay slot */
++
++	clobber_reg(ctx, MIPS_R_RA);
++	clobber_reg(ctx, MIPS_R_V0);
++	clobber_reg(ctx, MIPS_R_V1);
++	return 0;
++}
++
++/* Function tail call */
++static int emit_tail_call(struct jit_context *ctx)
++{
++	u8 ary = lo(bpf2mips32[BPF_REG_2]);
++	u8 ind = lo(bpf2mips32[BPF_REG_3]);
++	u8 t1 = MIPS_R_T8;
++	u8 t2 = MIPS_R_T9;
++	int off;
++
++	/*
++	 * Tail call:
++	 * eBPF R1   - function argument (context ptr), passed in a0-a1
++	 * eBPF R2   - ptr to object with array of function entry points
++	 * eBPF R3   - array index of function to be called
++	 * stack[sz] - remaining tail call count, initialized in prologue
++	 */
++
++	/* if (ind >= ary->map.max_entries) goto out */
++	off = offsetof(struct bpf_array, map.max_entries);
++	if (off > 0x7fff)
++		return -1;
++	emit(ctx, lw, t1, off, ary);             /* t1 = ary->map.max_entries*/
++	emit_load_delay(ctx);                    /* Load delay slot          */
++	emit(ctx, sltu, t1, ind, t1);            /* t1 = ind < t1            */
++	emit(ctx, beqz, t1, get_offset(ctx, 1)); /* PC += off(1) if t1 == 0  */
++						 /* (next insn delay slot)   */
++	/* if (TCC-- <= 0) goto out */
++	emit(ctx, lw, t2, ctx->stack_size, MIPS_R_SP);  /* t2 = *(SP + size) */
++	emit_load_delay(ctx);                     /* Load delay slot         */
++	emit(ctx, blez, t2, get_offset(ctx, 1));  /* PC += off(1) if t2 < 0  */
++	emit(ctx, addiu, t2, t2, -1);             /* t2-- (delay slot)       */
++	emit(ctx, sw, t2, ctx->stack_size, MIPS_R_SP);  /* *(SP + size) = t2 */
++
++	/* prog = ary->ptrs[ind] */
++	off = offsetof(struct bpf_array, ptrs);
++	if (off > 0x7fff)
++		return -1;
++	emit(ctx, sll, t1, ind, 2);               /* t1 = ind << 2           */
++	emit(ctx, addu, t1, t1, ary);             /* t1 += ary               */
++	emit(ctx, lw, t2, off, t1);               /* t2 = *(t1 + off)        */
++	emit_load_delay(ctx);                     /* Load delay slot         */
++
++	/* if (prog == 0) goto out */
++	emit(ctx, beqz, t2, get_offset(ctx, 1));  /* PC += off(1) if t2 == 0 */
++	emit(ctx, nop);                           /* Delay slot              */
++
++	/* func = prog->bpf_func + 8 (prologue skip offset) */
++	off = offsetof(struct bpf_prog, bpf_func);
++	if (off > 0x7fff)
++		return -1;
++	emit(ctx, lw, t1, off, t2);                /* t1 = *(t2 + off)       */
++	emit_load_delay(ctx);                      /* Load delay slot        */
++	emit(ctx, addiu, t1, t1, JIT_TCALL_SKIP);  /* t1 += skip (8 or 12)   */
++
++	/* goto func */
++	build_epilogue(ctx, t1);
++	return 0;
++}
++
++/*
++ * Stack frame layout for a JITed program (stack grows down).
++ *
++ * Higher address  : Caller's stack frame       :
++ *                 :----------------------------:
++ *                 : 64-bit eBPF args r3-r5     :
++ *                 :----------------------------:
++ *                 : Reserved / tail call count :
++ *                 +============================+  <--- MIPS sp before call
++ *                 | Callee-saved registers,    |
++ *                 | including RA and FP        |
++ *                 +----------------------------+  <--- eBPF FP (MIPS zero,fp)
++ *                 | Local eBPF variables       |
++ *                 | allocated by program       |
++ *                 +----------------------------+
++ *                 | Reserved for caller-saved  |
++ *                 | registers                  |
++ *                 +----------------------------+
++ *                 | Reserved for 64-bit eBPF   |
++ *                 | args r3-r5 & args passed   |
++ *                 | on stack in kernel calls   |
++ * Lower address   +============================+  <--- MIPS sp
++ */
++
++/* Build program prologue to set up the stack and registers */
++void build_prologue(struct jit_context *ctx)
++{
++	const u8 *r1 = bpf2mips32[BPF_REG_1];
++	const u8 *fp = bpf2mips32[BPF_REG_FP];
++	int stack, saved, locals, reserved;
++
++	/*
++	 * The first two instructions initialize TCC in the reserved (for us)
++	 * 16-byte area in the parent's stack frame. On a tail call, the
++	 * calling function jumps into the prologue after these instructions.
++	 */
++	emit(ctx, ori, MIPS_R_T9, MIPS_R_ZERO,
++	     min(MAX_TAIL_CALL_CNT + 1, 0xffff));
++	emit(ctx, sw, MIPS_R_T9, 0, MIPS_R_SP);
++
++	/*
++	 * Register eBPF R1 contains the 32-bit context pointer argument.
++	 * A 32-bit argument is always passed in MIPS register a0, regardless
++	 * of CPU endianness. Initialize R1 accordingly and zero-extend.
++	 */
++#ifdef __BIG_ENDIAN
++	emit(ctx, move, lo(r1), MIPS_R_A0);
++#endif
++
++	/* === Entry-point for tail calls === */
++
++	/* Zero-extend the 32-bit argument */
++	emit(ctx, move, hi(r1), MIPS_R_ZERO);
++
++	/* If the eBPF frame pointer was accessed it must be saved */
++	if (ctx->accessed & BIT(BPF_REG_FP))
++		clobber_reg64(ctx, fp);
++
++	/* Compute the stack space needed for callee-saved registers */
++	saved = hweight32(ctx->clobbered & JIT_CALLEE_REGS) * sizeof(u32);
++	saved = ALIGN(saved, MIPS_STACK_ALIGNMENT);
++
++	/* Stack space used by eBPF program local data */
++	locals = ALIGN(ctx->program->aux->stack_depth, MIPS_STACK_ALIGNMENT);
++
++	/*
++	 * If we are emitting function calls, reserve extra stack space for
++	 * caller-saved registers and function arguments passed on the stack.
++	 * The required space is computed automatically during resource
++	 * usage discovery (pass 1).
++	 */
++	reserved = ctx->stack_used;
++
++	/* Allocate the stack frame */
++	stack = ALIGN(saved + locals + reserved, MIPS_STACK_ALIGNMENT);
++	emit(ctx, addiu, MIPS_R_SP, MIPS_R_SP, -stack);
++
++	/* Store callee-saved registers on stack */
++	push_regs(ctx, ctx->clobbered & JIT_CALLEE_REGS, 0, stack - saved);
++
++	/* Initialize the eBPF frame pointer if accessed */
++	if (ctx->accessed & BIT(BPF_REG_FP))
++		emit(ctx, addiu, lo(fp), MIPS_R_SP, stack - saved);
++
++	ctx->saved_size = saved;
++	ctx->stack_size = stack;
++}
++
++/* Build the program epilogue to restore the stack and registers */
++void build_epilogue(struct jit_context *ctx, int dest_reg)
++{
++	/* Restore callee-saved registers from stack */
++	pop_regs(ctx, ctx->clobbered & JIT_CALLEE_REGS, 0,
++		 ctx->stack_size - ctx->saved_size);
++	/*
++	 * A 32-bit return value is always passed in MIPS register v0,
++	 * but on big-endian targets the low part of R0 is mapped to v1.
++	 */
++#ifdef __BIG_ENDIAN
++	emit(ctx, move, MIPS_R_V0, MIPS_R_V1);
++#endif
++
++	/* Jump to the return address and adjust the stack pointer */
++	emit(ctx, jr, dest_reg);
++	emit(ctx, addiu, MIPS_R_SP, MIPS_R_SP, ctx->stack_size);
++}
++
++/* Build one eBPF instruction */
++int build_insn(const struct bpf_insn *insn, struct jit_context *ctx)
++{
++	const u8 *dst = bpf2mips32[insn->dst_reg];
++	const u8 *src = bpf2mips32[insn->src_reg];
++	const u8 *tmp = bpf2mips32[JIT_REG_TMP];
++	u8 code = insn->code;
++	s16 off = insn->off;
++	s32 imm = insn->imm;
++	s32 val, rel;
++	u8 alu, jmp;
++
++	switch (code) {
++	/* ALU operations */
++	/* dst = imm */
++	case BPF_ALU | BPF_MOV | BPF_K:
++		emit_mov_i(ctx, lo(dst), imm);
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = src */
++	case BPF_ALU | BPF_MOV | BPF_X:
++		if (imm == 1) {
++			/* Special mov32 for zext */
++			emit_mov_i(ctx, hi(dst), 0);
++		} else {
++			emit_mov_r(ctx, lo(dst), lo(src));
++			emit_zext_ver(ctx, dst);
++		}
++		break;
++	/* dst = -dst */
++	case BPF_ALU | BPF_NEG:
++		emit_alu_i(ctx, lo(dst), 0, BPF_NEG);
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = dst & imm */
++	/* dst = dst | imm */
++	/* dst = dst ^ imm */
++	/* dst = dst << imm */
++	/* dst = dst >> imm */
++	/* dst = dst >> imm (arithmetic) */
++	/* dst = dst + imm */
++	/* dst = dst - imm */
++	/* dst = dst * imm */
++	/* dst = dst / imm */
++	/* dst = dst % imm */
++	case BPF_ALU | BPF_OR | BPF_K:
++	case BPF_ALU | BPF_AND | BPF_K:
++	case BPF_ALU | BPF_XOR | BPF_K:
++	case BPF_ALU | BPF_LSH | BPF_K:
++	case BPF_ALU | BPF_RSH | BPF_K:
++	case BPF_ALU | BPF_ARSH | BPF_K:
++	case BPF_ALU | BPF_ADD | BPF_K:
++	case BPF_ALU | BPF_SUB | BPF_K:
++	case BPF_ALU | BPF_MUL | BPF_K:
++	case BPF_ALU | BPF_DIV | BPF_K:
++	case BPF_ALU | BPF_MOD | BPF_K:
++		if (!valid_alu_i(BPF_OP(code), imm)) {
++			emit_mov_i(ctx, MIPS_R_T6, imm);
++			emit_alu_r(ctx, lo(dst), MIPS_R_T6, BPF_OP(code));
++		} else if (rewrite_alu_i(BPF_OP(code), imm, &alu, &val)) {
++			emit_alu_i(ctx, lo(dst), val, alu);
++		}
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = dst & src */
++	/* dst = dst | src */
++	/* dst = dst ^ src */
++	/* dst = dst << src */
++	/* dst = dst >> src */
++	/* dst = dst >> src (arithmetic) */
++	/* dst = dst + src */
++	/* dst = dst - src */
++	/* dst = dst * src */
++	/* dst = dst / src */
++	/* dst = dst % src */
++	case BPF_ALU | BPF_AND | BPF_X:
++	case BPF_ALU | BPF_OR | BPF_X:
++	case BPF_ALU | BPF_XOR | BPF_X:
++	case BPF_ALU | BPF_LSH | BPF_X:
++	case BPF_ALU | BPF_RSH | BPF_X:
++	case BPF_ALU | BPF_ARSH | BPF_X:
++	case BPF_ALU | BPF_ADD | BPF_X:
++	case BPF_ALU | BPF_SUB | BPF_X:
++	case BPF_ALU | BPF_MUL | BPF_X:
++	case BPF_ALU | BPF_DIV | BPF_X:
++	case BPF_ALU | BPF_MOD | BPF_X:
++		emit_alu_r(ctx, lo(dst), lo(src), BPF_OP(code));
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = imm (64-bit) */
++	case BPF_ALU64 | BPF_MOV | BPF_K:
++		emit_mov_se_i64(ctx, dst, imm);
++		break;
++	/* dst = src (64-bit) */
++	case BPF_ALU64 | BPF_MOV | BPF_X:
++		emit_mov_r(ctx, lo(dst), lo(src));
++		emit_mov_r(ctx, hi(dst), hi(src));
++		break;
++	/* dst = -dst (64-bit) */
++	case BPF_ALU64 | BPF_NEG:
++		emit_neg_i64(ctx, dst);
++		break;
++	/* dst = dst & imm (64-bit) */
++	case BPF_ALU64 | BPF_AND | BPF_K:
++		emit_alu_i64(ctx, dst, imm, BPF_OP(code));
++		break;
++	/* dst = dst | imm (64-bit) */
++	/* dst = dst ^ imm (64-bit) */
++	/* dst = dst + imm (64-bit) */
++	/* dst = dst - imm (64-bit) */
++	case BPF_ALU64 | BPF_OR | BPF_K:
++	case BPF_ALU64 | BPF_XOR | BPF_K:
++	case BPF_ALU64 | BPF_ADD | BPF_K:
++	case BPF_ALU64 | BPF_SUB | BPF_K:
++		if (imm)
++			emit_alu_i64(ctx, dst, imm, BPF_OP(code));
++		break;
++	/* dst = dst << imm (64-bit) */
++	/* dst = dst >> imm (64-bit) */
++	/* dst = dst >> imm (64-bit, arithmetic) */
++	case BPF_ALU64 | BPF_LSH | BPF_K:
++	case BPF_ALU64 | BPF_RSH | BPF_K:
++	case BPF_ALU64 | BPF_ARSH | BPF_K:
++		if (imm)
++			emit_shift_i64(ctx, dst, imm, BPF_OP(code));
++		break;
++	/* dst = dst * imm (64-bit) */
++	case BPF_ALU64 | BPF_MUL | BPF_K:
++		emit_mul_i64(ctx, dst, imm);
++		break;
++	/* dst = dst / imm (64-bit) */
++	/* dst = dst % imm (64-bit) */
++	case BPF_ALU64 | BPF_DIV | BPF_K:
++	case BPF_ALU64 | BPF_MOD | BPF_K:
++		/*
++		 * Sign-extend the immediate value into a temporary register,
++		 * and then do the operation on this register.
++		 */
++		emit_mov_se_i64(ctx, tmp, imm);
++		emit_divmod_r64(ctx, dst, tmp, BPF_OP(code));
++		break;
++	/* dst = dst & src (64-bit) */
++	/* dst = dst | src (64-bit) */
++	/* dst = dst ^ src (64-bit) */
++	/* dst = dst + src (64-bit) */
++	/* dst = dst - src (64-bit) */
++	case BPF_ALU64 | BPF_AND | BPF_X:
++	case BPF_ALU64 | BPF_OR | BPF_X:
++	case BPF_ALU64 | BPF_XOR | BPF_X:
++	case BPF_ALU64 | BPF_ADD | BPF_X:
++	case BPF_ALU64 | BPF_SUB | BPF_X:
++		emit_alu_r64(ctx, dst, src, BPF_OP(code));
++		break;
++	/* dst = dst << src (64-bit) */
++	/* dst = dst >> src (64-bit) */
++	/* dst = dst >> src (64-bit, arithmetic) */
++	case BPF_ALU64 | BPF_LSH | BPF_X:
++	case BPF_ALU64 | BPF_RSH | BPF_X:
++	case BPF_ALU64 | BPF_ARSH | BPF_X:
++		emit_shift_r64(ctx, dst, lo(src), BPF_OP(code));
++		break;
++	/* dst = dst * src (64-bit) */
++	case BPF_ALU64 | BPF_MUL | BPF_X:
++		emit_mul_r64(ctx, dst, src);
++		break;
++	/* dst = dst / src (64-bit) */
++	/* dst = dst % src (64-bit) */
++	case BPF_ALU64 | BPF_DIV | BPF_X:
++	case BPF_ALU64 | BPF_MOD | BPF_X:
++		emit_divmod_r64(ctx, dst, src, BPF_OP(code));
++		break;
++	/* dst = htole(dst) */
++	/* dst = htobe(dst) */
++	case BPF_ALU | BPF_END | BPF_FROM_LE:
++	case BPF_ALU | BPF_END | BPF_FROM_BE:
++		if (BPF_SRC(code) ==
++#ifdef __BIG_ENDIAN
++		    BPF_FROM_LE
++#else
++		    BPF_FROM_BE
++#endif
++		    )
++			emit_bswap_r64(ctx, dst, imm);
++		else
++			emit_trunc_r64(ctx, dst, imm);
++		break;
++	/* dst = imm64 */
++	case BPF_LD | BPF_IMM | BPF_DW:
++		emit_mov_i(ctx, lo(dst), imm);
++		emit_mov_i(ctx, hi(dst), insn[1].imm);
++		return 1;
++	/* LDX: dst = *(size *)(src + off) */
++	case BPF_LDX | BPF_MEM | BPF_W:
++	case BPF_LDX | BPF_MEM | BPF_H:
++	case BPF_LDX | BPF_MEM | BPF_B:
++	case BPF_LDX | BPF_MEM | BPF_DW:
++		emit_ldx(ctx, dst, lo(src), off, BPF_SIZE(code));
++		break;
++	/* ST: *(size *)(dst + off) = imm */
++	case BPF_ST | BPF_MEM | BPF_W:
++	case BPF_ST | BPF_MEM | BPF_H:
++	case BPF_ST | BPF_MEM | BPF_B:
++	case BPF_ST | BPF_MEM | BPF_DW:
++		switch (BPF_SIZE(code)) {
++		case BPF_DW:
++			/* Sign-extend immediate value into temporary reg */
++			emit_mov_se_i64(ctx, tmp, imm);
++			break;
++		case BPF_W:
++		case BPF_H:
++		case BPF_B:
++			emit_mov_i(ctx, lo(tmp), imm);
++			break;
++		}
++		emit_stx(ctx, lo(dst), tmp, off, BPF_SIZE(code));
++		break;
++	/* STX: *(size *)(dst + off) = src */
++	case BPF_STX | BPF_MEM | BPF_W:
++	case BPF_STX | BPF_MEM | BPF_H:
++	case BPF_STX | BPF_MEM | BPF_B:
++	case BPF_STX | BPF_MEM | BPF_DW:
++		emit_stx(ctx, lo(dst), src, off, BPF_SIZE(code));
++		break;
++	/* Speculation barrier */
++	case BPF_ST | BPF_NOSPEC:
++		break;
++	/* Atomics */
++	case BPF_STX | BPF_XADD | BPF_W:
++		switch (imm) {
++		case BPF_ADD:
++		case BPF_AND:
++		case BPF_OR:
++		case BPF_XOR:
++			if (cpu_has_llsc)
++				emit_atomic_r(ctx, lo(dst), lo(src), off, imm);
++			else /* Non-ll/sc fallback */
++				emit_atomic_r32(ctx, lo(dst), lo(src),
++						off, imm);
++			break;
++		default:
++			goto notyet;
++		}
++		break;
++	/* Atomics (64-bit) */
++	case BPF_STX | BPF_XADD | BPF_DW:
++		switch (imm) {
++		case BPF_ADD:
++		case BPF_AND:
++		case BPF_OR:
++		case BPF_XOR:
++			emit_atomic_r64(ctx, lo(dst), src, off, imm);
++			break;
++		default:
++			goto notyet;
++		}
++		break;
++	/* PC += off if dst == src */
++	/* PC += off if dst != src */
++	/* PC += off if dst & src */
++	/* PC += off if dst > src */
++	/* PC += off if dst >= src */
++	/* PC += off if dst < src */
++	/* PC += off if dst <= src */
++	/* PC += off if dst > src (signed) */
++	/* PC += off if dst >= src (signed) */
++	/* PC += off if dst < src (signed) */
++	/* PC += off if dst <= src (signed) */
++	case BPF_JMP32 | BPF_JEQ | BPF_X:
++	case BPF_JMP32 | BPF_JNE | BPF_X:
++	case BPF_JMP32 | BPF_JSET | 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:
++		if (off == 0)
++			break;
++		setup_jmp_r(ctx, dst == src, BPF_OP(code), off, &jmp, &rel);
++		emit_jmp_r(ctx, lo(dst), lo(src), rel, jmp);
++		if (finish_jmp(ctx, jmp, off) < 0)
++			goto toofar;
++		break;
++	/* PC += off if dst == imm */
++	/* PC += off if dst != imm */
++	/* PC += off if dst & imm */
++	/* PC += off if dst > imm */
++	/* PC += off if dst >= imm */
++	/* PC += off if dst < imm */
++	/* PC += off if dst <= imm */
++	/* PC += off if dst > imm (signed) */
++	/* PC += off if dst >= imm (signed) */
++	/* PC += off if dst < imm (signed) */
++	/* PC += off if dst <= imm (signed) */
++	case BPF_JMP32 | BPF_JEQ | BPF_K:
++	case BPF_JMP32 | BPF_JNE | BPF_K:
++	case BPF_JMP32 | BPF_JSET | 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:
++		if (off == 0)
++			break;
++		setup_jmp_i(ctx, imm, 32, BPF_OP(code), off, &jmp, &rel);
++		if (valid_jmp_i(jmp, imm)) {
++			emit_jmp_i(ctx, lo(dst), imm, rel, jmp);
++		} else {
++			/* Move large immediate to register */
++			emit_mov_i(ctx, MIPS_R_T6, imm);
++			emit_jmp_r(ctx, lo(dst), MIPS_R_T6, rel, jmp);
++		}
++		if (finish_jmp(ctx, jmp, off) < 0)
++			goto toofar;
++		break;
++	/* PC += off if dst == src */
++	/* PC += off if dst != src */
++	/* PC += off if dst & src */
++	/* PC += off if dst > src */
++	/* PC += off if dst >= src */
++	/* PC += off if dst < src */
++	/* PC += off if dst <= src */
++	/* PC += off if dst > src (signed) */
++	/* PC += off if dst >= src (signed) */
++	/* PC += off if dst < src (signed) */
++	/* PC += off if dst <= src (signed) */
++	case BPF_JMP | BPF_JEQ | BPF_X:
++	case BPF_JMP | BPF_JNE | BPF_X:
++	case BPF_JMP | BPF_JSET | 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:
++		if (off == 0)
++			break;
++		setup_jmp_r(ctx, dst == src, BPF_OP(code), off, &jmp, &rel);
++		emit_jmp_r64(ctx, dst, src, rel, jmp);
++		if (finish_jmp(ctx, jmp, off) < 0)
++			goto toofar;
++		break;
++	/* PC += off if dst == imm */
++	/* PC += off if dst != imm */
++	/* PC += off if dst & imm */
++	/* PC += off if dst > imm */
++	/* PC += off if dst >= imm */
++	/* PC += off if dst < imm */
++	/* PC += off if dst <= imm */
++	/* PC += off if dst > imm (signed) */
++	/* PC += off if dst >= imm (signed) */
++	/* PC += off if dst < imm (signed) */
++	/* PC += off if dst <= imm (signed) */
++	case BPF_JMP | BPF_JEQ | BPF_K:
++	case BPF_JMP | BPF_JNE | BPF_K:
++	case BPF_JMP | BPF_JSET | 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:
++		if (off == 0)
++			break;
++		setup_jmp_i(ctx, imm, 64, BPF_OP(code), off, &jmp, &rel);
++		emit_jmp_i64(ctx, dst, imm, rel, jmp);
++		if (finish_jmp(ctx, jmp, off) < 0)
++			goto toofar;
++		break;
++	/* PC += off */
++	case BPF_JMP | BPF_JA:
++		if (off == 0)
++			break;
++		if (emit_ja(ctx, off) < 0)
++			goto toofar;
++		break;
++	/* Tail call */
++	case BPF_JMP | BPF_TAIL_CALL:
++		if (emit_tail_call(ctx) < 0)
++			goto invalid;
++		break;
++	/* Function call */
++	case BPF_JMP | BPF_CALL:
++		if (emit_call(ctx, insn) < 0)
++			goto invalid;
++		break;
++	/* Function return */
++	case BPF_JMP | BPF_EXIT:
++		/*
++		 * Optimization: when last instruction is EXIT
++		 * simply continue to epilogue.
++		 */
++		if (ctx->bpf_index == ctx->program->len - 1)
++			break;
++		if (emit_exit(ctx) < 0)
++			goto toofar;
++		break;
++
++	default:
++invalid:
++		pr_err_once("unknown opcode %02x\n", code);
++		return -EINVAL;
++notyet:
++		pr_info_once("*** NOT YET: opcode %02x ***\n", code);
++		return -EFAULT;
++toofar:
++		pr_info_once("*** TOO FAR: jump at %u opcode %02x ***\n",
++			     ctx->bpf_index, code);
++		return -E2BIG;
++	}
++	return 0;
++}
diff --git a/target/linux/generic/backport-5.4/071-v5.16-03-mips-bpf-Add-new-eBPF-JIT-for-64-bit-MIPS.patch b/target/linux/generic/backport-5.4/071-v5.16-03-mips-bpf-Add-new-eBPF-JIT-for-64-bit-MIPS.patch
new file mode 100644
index 0000000000..38b46c0b76
--- /dev/null
+++ b/target/linux/generic/backport-5.4/071-v5.16-03-mips-bpf-Add-new-eBPF-JIT-for-64-bit-MIPS.patch
@@ -0,0 +1,1005 @@
+From: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+Date: Tue, 5 Oct 2021 18:54:05 +0200
+Subject: [PATCH] mips: bpf: Add new eBPF JIT for 64-bit MIPS
+
+This is an implementation on of an eBPF JIT for 64-bit MIPS III-V and
+MIPS64r1-r6. It uses the same framework introduced by the 32-bit JIT.
+
+Signed-off-by: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+---
+ create mode 100644 arch/mips/net/bpf_jit_comp64.c
+
+--- /dev/null
++++ b/arch/mips/net/bpf_jit_comp64.c
+@@ -0,0 +1,991 @@
++// SPDX-License-Identifier: GPL-2.0-only
++/*
++ * Just-In-Time compiler for eBPF bytecode on MIPS.
++ * Implementation of JIT functions for 64-bit CPUs.
++ *
++ * Copyright (c) 2021 Anyfi Networks AB.
++ * Author: Johan Almbladh <johan.almbladh at gmail.com>
++ *
++ * Based on code and ideas from
++ * Copyright (c) 2017 Cavium, Inc.
++ * Copyright (c) 2017 Shubham Bansal <illusionist.neo at gmail.com>
++ * Copyright (c) 2011 Mircea Gherzan <mgherzan at gmail.com>
++ */
++
++#include <linux/errno.h>
++#include <linux/filter.h>
++#include <linux/bpf.h>
++#include <asm/cpu-features.h>
++#include <asm/isa-rev.h>
++#include <asm/uasm.h>
++
++#include "bpf_jit_comp.h"
++
++/* MIPS t0-t3 are not available in the n64 ABI */
++#undef MIPS_R_T0
++#undef MIPS_R_T1
++#undef MIPS_R_T2
++#undef MIPS_R_T3
++
++/* Stack is 16-byte aligned in n64 ABI */
++#define MIPS_STACK_ALIGNMENT 16
++
++/* Extra 64-bit eBPF registers used by JIT */
++#define JIT_REG_TC (MAX_BPF_JIT_REG + 0)
++#define JIT_REG_ZX (MAX_BPF_JIT_REG + 1)
++
++/* Number of prologue bytes to skip when doing a tail call */
++#define JIT_TCALL_SKIP 4
++
++/* Callee-saved CPU registers that the JIT must preserve */
++#define JIT_CALLEE_REGS   \
++	(BIT(MIPS_R_S0) | \
++	 BIT(MIPS_R_S1) | \
++	 BIT(MIPS_R_S2) | \
++	 BIT(MIPS_R_S3) | \
++	 BIT(MIPS_R_S4) | \
++	 BIT(MIPS_R_S5) | \
++	 BIT(MIPS_R_S6) | \
++	 BIT(MIPS_R_S7) | \
++	 BIT(MIPS_R_GP) | \
++	 BIT(MIPS_R_FP) | \
++	 BIT(MIPS_R_RA))
++
++/* Caller-saved CPU registers available for JIT use */
++#define JIT_CALLER_REGS	  \
++	(BIT(MIPS_R_A5) | \
++	 BIT(MIPS_R_A6) | \
++	 BIT(MIPS_R_A7))
++/*
++ * Mapping of 64-bit eBPF registers to 64-bit native MIPS registers.
++ * MIPS registers t4 - t7 may be used by the JIT as temporary registers.
++ * MIPS registers t8 - t9 are reserved for single-register common functions.
++ */
++static const u8 bpf2mips64[] = {
++	/* Return value from in-kernel function, and exit value from eBPF */
++	[BPF_REG_0] = MIPS_R_V0,
++	/* Arguments from eBPF program to in-kernel function */
++	[BPF_REG_1] = MIPS_R_A0,
++	[BPF_REG_2] = MIPS_R_A1,
++	[BPF_REG_3] = MIPS_R_A2,
++	[BPF_REG_4] = MIPS_R_A3,
++	[BPF_REG_5] = MIPS_R_A4,
++	/* Callee-saved registers that in-kernel function will preserve */
++	[BPF_REG_6] = MIPS_R_S0,
++	[BPF_REG_7] = MIPS_R_S1,
++	[BPF_REG_8] = MIPS_R_S2,
++	[BPF_REG_9] = MIPS_R_S3,
++	/* Read-only frame pointer to access the eBPF stack */
++	[BPF_REG_FP] = MIPS_R_FP,
++	/* Temporary register for blinding constants */
++	[BPF_REG_AX] = MIPS_R_AT,
++	/* Tail call count register, caller-saved */
++	[JIT_REG_TC] = MIPS_R_A5,
++	/* Constant for register zero-extension */
++	[JIT_REG_ZX] = MIPS_R_V1,
++};
++
++/*
++ * MIPS 32-bit operations on 64-bit registers generate a sign-extended
++ * result. However, the eBPF ISA mandates zero-extension, so we rely on the
++ * verifier to add that for us (emit_zext_ver). In addition, ALU arithmetic
++ * operations, right shift and byte swap require properly sign-extended
++ * operands or the result is unpredictable. We emit explicit sign-extensions
++ * in those cases.
++ */
++
++/* Sign extension */
++static void emit_sext(struct jit_context *ctx, u8 dst, u8 src)
++{
++	emit(ctx, sll, dst, src, 0);
++	clobber_reg(ctx, dst);
++}
++
++/* Zero extension */
++static void emit_zext(struct jit_context *ctx, u8 dst)
++{
++	if (cpu_has_mips64r2 || cpu_has_mips64r6) {
++		emit(ctx, dinsu, dst, MIPS_R_ZERO, 32, 32);
++	} else {
++		emit(ctx, and, dst, dst, bpf2mips64[JIT_REG_ZX]);
++		access_reg(ctx, JIT_REG_ZX); /* We need the ZX register */
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* Zero extension, if verifier does not do it for us  */
++static void emit_zext_ver(struct jit_context *ctx, u8 dst)
++{
++	if (!ctx->program->aux->verifier_zext)
++		emit_zext(ctx, dst);
++}
++
++/* dst = imm (64-bit) */
++static void emit_mov_i64(struct jit_context *ctx, u8 dst, u64 imm64)
++{
++	if (imm64 >= 0xffffffffffff8000ULL || imm64 < 0x8000ULL) {
++		emit(ctx, daddiu, dst, MIPS_R_ZERO, (s16)imm64);
++	} else if (imm64 >= 0xffffffff80000000ULL ||
++		   (imm64 < 0x80000000 && imm64 > 0xffff)) {
++		emit(ctx, lui, dst, (s16)(imm64 >> 16));
++		emit(ctx, ori, dst, dst, (u16)imm64 & 0xffff);
++	} else {
++		u8 acc = MIPS_R_ZERO;
++		int k;
++
++		for (k = 0; k < 4; k++) {
++			u16 half = imm64 >> (48 - 16 * k);
++
++			if (acc == dst)
++				emit(ctx, dsll, dst, dst, 16);
++
++			if (half) {
++				emit(ctx, ori, dst, acc, half);
++				acc = dst;
++			}
++		}
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* ALU immediate operation (64-bit) */
++static void emit_alu_i64(struct jit_context *ctx, u8 dst, s32 imm, u8 op)
++{
++	switch (BPF_OP(op)) {
++	/* dst = dst | imm */
++	case BPF_OR:
++		emit(ctx, ori, dst, dst, (u16)imm);
++		break;
++	/* dst = dst ^ imm */
++	case BPF_XOR:
++		emit(ctx, xori, dst, dst, (u16)imm);
++		break;
++	/* dst = -dst */
++	case BPF_NEG:
++		emit(ctx, dsubu, dst, MIPS_R_ZERO, dst);
++		break;
++	/* dst = dst << imm */
++	case BPF_LSH:
++		emit(ctx, dsll_safe, dst, dst, imm);
++		break;
++	/* dst = dst >> imm */
++	case BPF_RSH:
++		emit(ctx, dsrl_safe, dst, dst, imm);
++		break;
++	/* dst = dst >> imm (arithmetic) */
++	case BPF_ARSH:
++		emit(ctx, dsra_safe, dst, dst, imm);
++		break;
++	/* dst = dst + imm */
++	case BPF_ADD:
++		emit(ctx, daddiu, dst, dst, imm);
++		break;
++	/* dst = dst - imm */
++	case BPF_SUB:
++		emit(ctx, daddiu, dst, dst, -imm);
++		break;
++	default:
++		/* Width-generic operations */
++		emit_alu_i(ctx, dst, imm, op);
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* ALU register operation (64-bit) */
++static void emit_alu_r64(struct jit_context *ctx, u8 dst, u8 src, u8 op)
++{
++	switch (BPF_OP(op)) {
++	/* dst = dst << src */
++	case BPF_LSH:
++		emit(ctx, dsllv, dst, dst, src);
++		break;
++	/* dst = dst >> src */
++	case BPF_RSH:
++		emit(ctx, dsrlv, dst, dst, src);
++		break;
++	/* dst = dst >> src (arithmetic) */
++	case BPF_ARSH:
++		emit(ctx, dsrav, dst, dst, src);
++		break;
++	/* dst = dst + src */
++	case BPF_ADD:
++		emit(ctx, daddu, dst, dst, src);
++		break;
++	/* dst = dst - src */
++	case BPF_SUB:
++		emit(ctx, dsubu, dst, dst, src);
++		break;
++	/* dst = dst * src */
++	case BPF_MUL:
++		if (cpu_has_mips64r6) {
++			emit(ctx, dmulu, dst, dst, src);
++		} else {
++			emit(ctx, dmultu, dst, src);
++			emit(ctx, mflo, dst);
++		}
++		break;
++	/* dst = dst / src */
++	case BPF_DIV:
++		if (cpu_has_mips64r6) {
++			emit(ctx, ddivu_r6, dst, dst, src);
++		} else {
++			emit(ctx, ddivu, dst, src);
++			emit(ctx, mflo, dst);
++		}
++		break;
++	/* dst = dst % src */
++	case BPF_MOD:
++		if (cpu_has_mips64r6) {
++			emit(ctx, dmodu, dst, dst, src);
++		} else {
++			emit(ctx, ddivu, dst, src);
++			emit(ctx, mfhi, dst);
++		}
++		break;
++	default:
++		/* Width-generic operations */
++		emit_alu_r(ctx, dst, src, op);
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* Swap sub words in a register double word */
++static void emit_swap_r64(struct jit_context *ctx, u8 dst, u8 mask, u32 bits)
++{
++	u8 tmp = MIPS_R_T9;
++
++	emit(ctx, and, tmp, dst, mask);  /* tmp = dst & mask  */
++	emit(ctx, dsll, tmp, tmp, bits); /* tmp = tmp << bits */
++	emit(ctx, dsrl, dst, dst, bits); /* dst = dst >> bits */
++	emit(ctx, and, dst, dst, mask);  /* dst = dst & mask  */
++	emit(ctx, or, dst, dst, tmp);    /* dst = dst | tmp   */
++}
++
++/* Swap bytes and truncate a register double word, word or half word */
++static void emit_bswap_r64(struct jit_context *ctx, u8 dst, u32 width)
++{
++	switch (width) {
++	/* Swap bytes in a double word */
++	case 64:
++		if (cpu_has_mips64r2 || cpu_has_mips64r6) {
++			emit(ctx, dsbh, dst, dst);
++			emit(ctx, dshd, dst, dst);
++		} else {
++			u8 t1 = MIPS_R_T6;
++			u8 t2 = MIPS_R_T7;
++
++			emit(ctx, dsll32, t2, dst, 0);  /* t2 = dst << 32    */
++			emit(ctx, dsrl32, dst, dst, 0); /* dst = dst >> 32   */
++			emit(ctx, or, dst, dst, t2);    /* dst = dst | t2    */
++
++			emit(ctx, ori, t2, MIPS_R_ZERO, 0xffff);
++			emit(ctx, dsll32, t1, t2, 0);   /* t1 = t2 << 32     */
++			emit(ctx, or, t1, t1, t2);      /* t1 = t1 | t2      */
++			emit_swap_r64(ctx, dst, t1, 16);/* dst = swap16(dst) */
++
++			emit(ctx, lui, t2, 0xff);       /* t2 = 0x00ff0000   */
++			emit(ctx, ori, t2, t2, 0xff);   /* t2 = t2 | 0x00ff  */
++			emit(ctx, dsll32, t1, t2, 0);   /* t1 = t2 << 32     */
++			emit(ctx, or, t1, t1, t2);      /* t1 = t1 | t2      */
++			emit_swap_r64(ctx, dst, t1, 8); /* dst = swap8(dst)  */
++		}
++		break;
++	/* Swap bytes in a half word */
++	/* Swap bytes in a word */
++	case 32:
++	case 16:
++		emit_sext(ctx, dst, dst);
++		emit_bswap_r(ctx, dst, width);
++		if (cpu_has_mips64r2 || cpu_has_mips64r6)
++			emit_zext(ctx, dst);
++		break;
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* Truncate a register double word, word or half word */
++static void emit_trunc_r64(struct jit_context *ctx, u8 dst, u32 width)
++{
++	switch (width) {
++	case 64:
++		break;
++	/* Zero-extend a word */
++	case 32:
++		emit_zext(ctx, dst);
++		break;
++	/* Zero-extend a half word */
++	case 16:
++		emit(ctx, andi, dst, dst, 0xffff);
++		break;
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* Load operation: dst = *(size*)(src + off) */
++static void emit_ldx(struct jit_context *ctx, u8 dst, u8 src, s16 off, u8 size)
++{
++	switch (size) {
++	/* Load a byte */
++	case BPF_B:
++		emit(ctx, lbu, dst, off, src);
++		break;
++	/* Load a half word */
++	case BPF_H:
++		emit(ctx, lhu, dst, off, src);
++		break;
++	/* Load a word */
++	case BPF_W:
++		emit(ctx, lwu, dst, off, src);
++		break;
++	/* Load a double word */
++	case BPF_DW:
++		emit(ctx, ld, dst, off, src);
++		break;
++	}
++	clobber_reg(ctx, dst);
++}
++
++/* Store operation: *(size *)(dst + off) = src */
++static void emit_stx(struct jit_context *ctx, u8 dst, u8 src, s16 off, u8 size)
++{
++	switch (size) {
++	/* Store a byte */
++	case BPF_B:
++		emit(ctx, sb, src, off, dst);
++		break;
++	/* Store a half word */
++	case BPF_H:
++		emit(ctx, sh, src, off, dst);
++		break;
++	/* Store a word */
++	case BPF_W:
++		emit(ctx, sw, src, off, dst);
++		break;
++	/* Store a double word */
++	case BPF_DW:
++		emit(ctx, sd, src, off, dst);
++		break;
++	}
++}
++
++/* Atomic read-modify-write */
++static void emit_atomic_r64(struct jit_context *ctx,
++			    u8 dst, u8 src, s16 off, u8 code)
++{
++	u8 t1 = MIPS_R_T6;
++	u8 t2 = MIPS_R_T7;
++
++	emit(ctx, lld, t1, off, dst);
++	switch (code) {
++	case BPF_ADD:
++		emit(ctx, daddu, t2, t1, src);
++		break;
++	case BPF_AND:
++		emit(ctx, and, t2, t1, src);
++		break;
++	case BPF_OR:
++		emit(ctx, or, t2, t1, src);
++		break;
++	case BPF_XOR:
++		emit(ctx, xor, t2, t1, src);
++		break;
++	}
++	emit(ctx, scd, t2, off, dst);
++	emit(ctx, beqz, t2, -16);
++	emit(ctx, nop); /* Delay slot */
++}
++
++/* Function call */
++static int emit_call(struct jit_context *ctx, const struct bpf_insn *insn)
++{
++	u8 zx = bpf2mips64[JIT_REG_ZX];
++	u8 tmp = MIPS_R_T6;
++	bool fixed;
++	u64 addr;
++
++	/* Decode the call address */
++	if (bpf_jit_get_func_addr(ctx->program, insn, false,
++				  &addr, &fixed) < 0)
++		return -1;
++	if (!fixed)
++		return -1;
++
++	/* Push caller-saved registers on stack */
++	push_regs(ctx, ctx->clobbered & JIT_CALLER_REGS, 0, 0);
++
++	/* Emit function call */
++	emit_mov_i64(ctx, tmp, addr);
++	emit(ctx, jalr, MIPS_R_RA, tmp);
++	emit(ctx, nop); /* Delay slot */
++
++	/* Restore caller-saved registers */
++	pop_regs(ctx, ctx->clobbered & JIT_CALLER_REGS, 0, 0);
++
++	/* Re-initialize the JIT zero-extension register if accessed */
++	if (ctx->accessed & BIT(JIT_REG_ZX)) {
++		emit(ctx, daddiu, zx, MIPS_R_ZERO, -1);
++		emit(ctx, dsrl32, zx, zx, 0);
++	}
++
++	clobber_reg(ctx, MIPS_R_RA);
++	clobber_reg(ctx, MIPS_R_V0);
++	clobber_reg(ctx, MIPS_R_V1);
++	return 0;
++}
++
++/* Function tail call */
++static int emit_tail_call(struct jit_context *ctx)
++{
++	u8 ary = bpf2mips64[BPF_REG_2];
++	u8 ind = bpf2mips64[BPF_REG_3];
++	u8 tcc = bpf2mips64[JIT_REG_TC];
++	u8 tmp = MIPS_R_T6;
++	int off;
++
++	/*
++	 * Tail call:
++	 * eBPF R1 - function argument (context ptr), passed in a0-a1
++	 * eBPF R2 - ptr to object with array of function entry points
++	 * eBPF R3 - array index of function to be called
++	 */
++
++	/* if (ind >= ary->map.max_entries) goto out */
++	off = offsetof(struct bpf_array, map.max_entries);
++	if (off > 0x7fff)
++		return -1;
++	emit(ctx, lwu, tmp, off, ary);            /* tmp = ary->map.max_entrs*/
++	emit(ctx, sltu, tmp, ind, tmp);           /* tmp = ind < t1          */
++	emit(ctx, beqz, tmp, get_offset(ctx, 1)); /* PC += off(1) if tmp == 0*/
++
++	/* if (--TCC < 0) goto out */
++	emit(ctx, daddiu, tcc, tcc, -1);          /* tcc-- (delay slot)      */
++	emit(ctx, bltz, tcc, get_offset(ctx, 1)); /* PC += off(1) if tcc < 0 */
++						  /* (next insn delay slot)  */
++	/* prog = ary->ptrs[ind] */
++	off = offsetof(struct bpf_array, ptrs);
++	if (off > 0x7fff)
++		return -1;
++	emit(ctx, dsll, tmp, ind, 3);             /* tmp = ind << 3          */
++	emit(ctx, daddu, tmp, tmp, ary);          /* tmp += ary              */
++	emit(ctx, ld, tmp, off, tmp);             /* tmp = *(tmp + off)      */
++
++	/* if (prog == 0) goto out */
++	emit(ctx, beqz, tmp, get_offset(ctx, 1)); /* PC += off(1) if tmp == 0*/
++	emit(ctx, nop);                           /* Delay slot              */
++
++	/* func = prog->bpf_func + 8 (prologue skip offset) */
++	off = offsetof(struct bpf_prog, bpf_func);
++	if (off > 0x7fff)
++		return -1;
++	emit(ctx, ld, tmp, off, tmp);                /* tmp = *(tmp + off)   */
++	emit(ctx, daddiu, tmp, tmp, JIT_TCALL_SKIP); /* tmp += skip (4)      */
++
++	/* goto func */
++	build_epilogue(ctx, tmp);
++	access_reg(ctx, JIT_REG_TC);
++	return 0;
++}
++
++/*
++ * Stack frame layout for a JITed program (stack grows down).
++ *
++ * Higher address  : Previous stack frame      :
++ *                 +===========================+  <--- MIPS sp before call
++ *                 | Callee-saved registers,   |
++ *                 | including RA and FP       |
++ *                 +---------------------------+  <--- eBPF FP (MIPS fp)
++ *                 | Local eBPF variables      |
++ *                 | allocated by program      |
++ *                 +---------------------------+
++ *                 | Reserved for caller-saved |
++ *                 | registers                 |
++ * Lower address   +===========================+  <--- MIPS sp
++ */
++
++/* Build program prologue to set up the stack and registers */
++void build_prologue(struct jit_context *ctx)
++{
++	u8 fp = bpf2mips64[BPF_REG_FP];
++	u8 tc = bpf2mips64[JIT_REG_TC];
++	u8 zx = bpf2mips64[JIT_REG_ZX];
++	int stack, saved, locals, reserved;
++
++	/*
++	 * The first instruction initializes the tail call count register.
++	 * On a tail call, the calling function jumps into the prologue
++	 * after this instruction.
++	 */
++	emit(ctx, addiu, tc, MIPS_R_ZERO, min(MAX_TAIL_CALL_CNT + 1, 0xffff));
++
++	/* === Entry-point for tail calls === */
++
++	/*
++	 * If the eBPF frame pointer and tail call count registers were
++	 * accessed they must be preserved. Mark them as clobbered here
++	 * to save and restore them on the stack as needed.
++	 */
++	if (ctx->accessed & BIT(BPF_REG_FP))
++		clobber_reg(ctx, fp);
++	if (ctx->accessed & BIT(JIT_REG_TC))
++		clobber_reg(ctx, tc);
++	if (ctx->accessed & BIT(JIT_REG_ZX))
++		clobber_reg(ctx, zx);
++
++	/* Compute the stack space needed for callee-saved registers */
++	saved = hweight32(ctx->clobbered & JIT_CALLEE_REGS) * sizeof(u64);
++	saved = ALIGN(saved, MIPS_STACK_ALIGNMENT);
++
++	/* Stack space used by eBPF program local data */
++	locals = ALIGN(ctx->program->aux->stack_depth, MIPS_STACK_ALIGNMENT);
++
++	/*
++	 * If we are emitting function calls, reserve extra stack space for
++	 * caller-saved registers needed by the JIT. The required space is
++	 * computed automatically during resource usage discovery (pass 1).
++	 */
++	reserved = ctx->stack_used;
++
++	/* Allocate the stack frame */
++	stack = ALIGN(saved + locals + reserved, MIPS_STACK_ALIGNMENT);
++	if (stack)
++		emit(ctx, daddiu, MIPS_R_SP, MIPS_R_SP, -stack);
++
++	/* Store callee-saved registers on stack */
++	push_regs(ctx, ctx->clobbered & JIT_CALLEE_REGS, 0, stack - saved);
++
++	/* Initialize the eBPF frame pointer if accessed */
++	if (ctx->accessed & BIT(BPF_REG_FP))
++		emit(ctx, daddiu, fp, MIPS_R_SP, stack - saved);
++
++	/* Initialize the ePF JIT zero-extension register if accessed */
++	if (ctx->accessed & BIT(JIT_REG_ZX)) {
++		emit(ctx, daddiu, zx, MIPS_R_ZERO, -1);
++		emit(ctx, dsrl32, zx, zx, 0);
++	}
++
++	ctx->saved_size = saved;
++	ctx->stack_size = stack;
++}
++
++/* Build the program epilogue to restore the stack and registers */
++void build_epilogue(struct jit_context *ctx, int dest_reg)
++{
++	/* Restore callee-saved registers from stack */
++	pop_regs(ctx, ctx->clobbered & JIT_CALLEE_REGS, 0,
++		 ctx->stack_size - ctx->saved_size);
++
++	/* Release the stack frame */
++	if (ctx->stack_size)
++		emit(ctx, daddiu, MIPS_R_SP, MIPS_R_SP, ctx->stack_size);
++
++	/* Jump to return address and sign-extend the 32-bit return value */
++	emit(ctx, jr, dest_reg);
++	emit(ctx, sll, MIPS_R_V0, MIPS_R_V0, 0); /* Delay slot */
++}
++
++/* Build one eBPF instruction */
++int build_insn(const struct bpf_insn *insn, struct jit_context *ctx)
++{
++	u8 dst = bpf2mips64[insn->dst_reg];
++	u8 src = bpf2mips64[insn->src_reg];
++	u8 code = insn->code;
++	s16 off = insn->off;
++	s32 imm = insn->imm;
++	s32 val, rel;
++	u8 alu, jmp;
++
++	switch (code) {
++	/* ALU operations */
++	/* dst = imm */
++	case BPF_ALU | BPF_MOV | BPF_K:
++		emit_mov_i(ctx, dst, imm);
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = src */
++	case BPF_ALU | BPF_MOV | BPF_X:
++		if (imm == 1) {
++			/* Special mov32 for zext */
++			emit_zext(ctx, dst);
++		} else {
++			emit_mov_r(ctx, dst, src);
++			emit_zext_ver(ctx, dst);
++		}
++		break;
++	/* dst = -dst */
++	case BPF_ALU | BPF_NEG:
++		emit_sext(ctx, dst, dst);
++		emit_alu_i(ctx, dst, 0, BPF_NEG);
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = dst & imm */
++	/* dst = dst | imm */
++	/* dst = dst ^ imm */
++	/* dst = dst << imm */
++	case BPF_ALU | BPF_OR | BPF_K:
++	case BPF_ALU | BPF_AND | BPF_K:
++	case BPF_ALU | BPF_XOR | BPF_K:
++	case BPF_ALU | BPF_LSH | BPF_K:
++		if (!valid_alu_i(BPF_OP(code), imm)) {
++			emit_mov_i(ctx, MIPS_R_T4, imm);
++			emit_alu_r(ctx, dst, MIPS_R_T4, BPF_OP(code));
++		} else if (rewrite_alu_i(BPF_OP(code), imm, &alu, &val)) {
++			emit_alu_i(ctx, dst, val, alu);
++		}
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = dst >> imm */
++	/* dst = dst >> imm (arithmetic) */
++	/* dst = dst + imm */
++	/* dst = dst - imm */
++	/* dst = dst * imm */
++	/* dst = dst / imm */
++	/* dst = dst % imm */
++	case BPF_ALU | BPF_RSH | BPF_K:
++	case BPF_ALU | BPF_ARSH | BPF_K:
++	case BPF_ALU | BPF_ADD | BPF_K:
++	case BPF_ALU | BPF_SUB | BPF_K:
++	case BPF_ALU | BPF_MUL | BPF_K:
++	case BPF_ALU | BPF_DIV | BPF_K:
++	case BPF_ALU | BPF_MOD | BPF_K:
++		if (!valid_alu_i(BPF_OP(code), imm)) {
++			emit_sext(ctx, dst, dst);
++			emit_mov_i(ctx, MIPS_R_T4, imm);
++			emit_alu_r(ctx, dst, MIPS_R_T4, BPF_OP(code));
++		} else if (rewrite_alu_i(BPF_OP(code), imm, &alu, &val)) {
++			emit_sext(ctx, dst, dst);
++			emit_alu_i(ctx, dst, val, alu);
++		}
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = dst & src */
++	/* dst = dst | src */
++	/* dst = dst ^ src */
++	/* dst = dst << src */
++	case BPF_ALU | BPF_AND | BPF_X:
++	case BPF_ALU | BPF_OR | BPF_X:
++	case BPF_ALU | BPF_XOR | BPF_X:
++	case BPF_ALU | BPF_LSH | BPF_X:
++		emit_alu_r(ctx, dst, src, BPF_OP(code));
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = dst >> src */
++	/* dst = dst >> src (arithmetic) */
++	/* dst = dst + src */
++	/* dst = dst - src */
++	/* dst = dst * src */
++	/* dst = dst / src */
++	/* dst = dst % src */
++	case BPF_ALU | BPF_RSH | BPF_X:
++	case BPF_ALU | BPF_ARSH | BPF_X:
++	case BPF_ALU | BPF_ADD | BPF_X:
++	case BPF_ALU | BPF_SUB | BPF_X:
++	case BPF_ALU | BPF_MUL | BPF_X:
++	case BPF_ALU | BPF_DIV | BPF_X:
++	case BPF_ALU | BPF_MOD | BPF_X:
++		emit_sext(ctx, dst, dst);
++		emit_sext(ctx, MIPS_R_T4, src);
++		emit_alu_r(ctx, dst, MIPS_R_T4, BPF_OP(code));
++		emit_zext_ver(ctx, dst);
++		break;
++	/* dst = imm (64-bit) */
++	case BPF_ALU64 | BPF_MOV | BPF_K:
++		emit_mov_i(ctx, dst, imm);
++		break;
++	/* dst = src (64-bit) */
++	case BPF_ALU64 | BPF_MOV | BPF_X:
++		emit_mov_r(ctx, dst, src);
++		break;
++	/* dst = -dst (64-bit) */
++	case BPF_ALU64 | BPF_NEG:
++		emit_alu_i64(ctx, dst, 0, BPF_NEG);
++		break;
++	/* dst = dst & imm (64-bit) */
++	/* dst = dst | imm (64-bit) */
++	/* dst = dst ^ imm (64-bit) */
++	/* dst = dst << imm (64-bit) */
++	/* dst = dst >> imm (64-bit) */
++	/* dst = dst >> imm ((64-bit, arithmetic) */
++	/* dst = dst + imm (64-bit) */
++	/* dst = dst - imm (64-bit) */
++	/* dst = dst * imm (64-bit) */
++	/* dst = dst / imm (64-bit) */
++	/* dst = dst % imm (64-bit) */
++	case BPF_ALU64 | BPF_AND | BPF_K:
++	case BPF_ALU64 | BPF_OR | BPF_K:
++	case BPF_ALU64 | BPF_XOR | BPF_K:
++	case BPF_ALU64 | BPF_LSH | BPF_K:
++	case BPF_ALU64 | BPF_RSH | BPF_K:
++	case BPF_ALU64 | BPF_ARSH | BPF_K:
++	case BPF_ALU64 | BPF_ADD | BPF_K:
++	case BPF_ALU64 | BPF_SUB | BPF_K:
++	case BPF_ALU64 | BPF_MUL | BPF_K:
++	case BPF_ALU64 | BPF_DIV | BPF_K:
++	case BPF_ALU64 | BPF_MOD | BPF_K:
++		if (!valid_alu_i(BPF_OP(code), imm)) {
++			emit_mov_i(ctx, MIPS_R_T4, imm);
++			emit_alu_r64(ctx, dst, MIPS_R_T4, BPF_OP(code));
++		} else if (rewrite_alu_i(BPF_OP(code), imm, &alu, &val)) {
++			emit_alu_i64(ctx, dst, val, alu);
++		}
++		break;
++	/* dst = dst & src (64-bit) */
++	/* dst = dst | src (64-bit) */
++	/* dst = dst ^ src (64-bit) */
++	/* dst = dst << src (64-bit) */
++	/* dst = dst >> src (64-bit) */
++	/* dst = dst >> src (64-bit, arithmetic) */
++	/* dst = dst + src (64-bit) */
++	/* dst = dst - src (64-bit) */
++	/* dst = dst * src (64-bit) */
++	/* dst = dst / src (64-bit) */
++	/* dst = dst % src (64-bit) */
++	case BPF_ALU64 | BPF_AND | BPF_X:
++	case BPF_ALU64 | BPF_OR | BPF_X:
++	case BPF_ALU64 | BPF_XOR | BPF_X:
++	case BPF_ALU64 | BPF_LSH | BPF_X:
++	case BPF_ALU64 | BPF_RSH | BPF_X:
++	case BPF_ALU64 | BPF_ARSH | BPF_X:
++	case BPF_ALU64 | BPF_ADD | BPF_X:
++	case BPF_ALU64 | BPF_SUB | BPF_X:
++	case BPF_ALU64 | BPF_MUL | BPF_X:
++	case BPF_ALU64 | BPF_DIV | BPF_X:
++	case BPF_ALU64 | BPF_MOD | BPF_X:
++		emit_alu_r64(ctx, dst, src, BPF_OP(code));
++		break;
++	/* dst = htole(dst) */
++	/* dst = htobe(dst) */
++	case BPF_ALU | BPF_END | BPF_FROM_LE:
++	case BPF_ALU | BPF_END | BPF_FROM_BE:
++		if (BPF_SRC(code) ==
++#ifdef __BIG_ENDIAN
++		    BPF_FROM_LE
++#else
++		    BPF_FROM_BE
++#endif
++		    )
++			emit_bswap_r64(ctx, dst, imm);
++		else
++			emit_trunc_r64(ctx, dst, imm);
++		break;
++	/* dst = imm64 */
++	case BPF_LD | BPF_IMM | BPF_DW:
++		emit_mov_i64(ctx, dst, (u32)imm | ((u64)insn[1].imm << 32));
++		return 1;
++	/* LDX: dst = *(size *)(src + off) */
++	case BPF_LDX | BPF_MEM | BPF_W:
++	case BPF_LDX | BPF_MEM | BPF_H:
++	case BPF_LDX | BPF_MEM | BPF_B:
++	case BPF_LDX | BPF_MEM | BPF_DW:
++		emit_ldx(ctx, dst, src, off, BPF_SIZE(code));
++		break;
++	/* ST: *(size *)(dst + off) = imm */
++	case BPF_ST | BPF_MEM | BPF_W:
++	case BPF_ST | BPF_MEM | BPF_H:
++	case BPF_ST | BPF_MEM | BPF_B:
++	case BPF_ST | BPF_MEM | BPF_DW:
++		emit_mov_i(ctx, MIPS_R_T4, imm);
++		emit_stx(ctx, dst, MIPS_R_T4, off, BPF_SIZE(code));
++		break;
++	/* STX: *(size *)(dst + off) = src */
++	case BPF_STX | BPF_MEM | BPF_W:
++	case BPF_STX | BPF_MEM | BPF_H:
++	case BPF_STX | BPF_MEM | BPF_B:
++	case BPF_STX | BPF_MEM | BPF_DW:
++		emit_stx(ctx, dst, src, off, BPF_SIZE(code));
++		break;
++	/* Speculation barrier */
++	case BPF_ST | BPF_NOSPEC:
++		break;
++	/* Atomics */
++	case BPF_STX | BPF_XADD | BPF_W:
++	case BPF_STX | BPF_XADD | BPF_DW:
++		switch (imm) {
++		case BPF_ADD:
++		case BPF_AND:
++		case BPF_OR:
++		case BPF_XOR:
++			if (BPF_SIZE(code) == BPF_DW) {
++				emit_atomic_r64(ctx, dst, src, off, imm);
++			} else { /* 32-bit, no fetch */
++				emit_sext(ctx, MIPS_R_T4, src);
++				emit_atomic_r(ctx, dst, MIPS_R_T4, off, imm);
++			}
++			break;
++		default:
++			goto notyet;
++		}
++		break;
++	/* PC += off if dst == src */
++	/* PC += off if dst != src */
++	/* PC += off if dst & src */
++	/* PC += off if dst > src */
++	/* PC += off if dst >= src */
++	/* PC += off if dst < src */
++	/* PC += off if dst <= src */
++	/* PC += off if dst > src (signed) */
++	/* PC += off if dst >= src (signed) */
++	/* PC += off if dst < src (signed) */
++	/* PC += off if dst <= src (signed) */
++	case BPF_JMP32 | BPF_JEQ | BPF_X:
++	case BPF_JMP32 | BPF_JNE | BPF_X:
++	case BPF_JMP32 | BPF_JSET | 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:
++		if (off == 0)
++			break;
++		setup_jmp_r(ctx, dst == src, BPF_OP(code), off, &jmp, &rel);
++		emit_sext(ctx, MIPS_R_T4, dst); /* Sign-extended dst */
++		emit_sext(ctx, MIPS_R_T5, src); /* Sign-extended src */
++		emit_jmp_r(ctx, MIPS_R_T4, MIPS_R_T5, rel, jmp);
++		if (finish_jmp(ctx, jmp, off) < 0)
++			goto toofar;
++		break;
++	/* PC += off if dst == imm */
++	/* PC += off if dst != imm */
++	/* PC += off if dst & imm */
++	/* PC += off if dst > imm */
++	/* PC += off if dst >= imm */
++	/* PC += off if dst < imm */
++	/* PC += off if dst <= imm */
++	/* PC += off if dst > imm (signed) */
++	/* PC += off if dst >= imm (signed) */
++	/* PC += off if dst < imm (signed) */
++	/* PC += off if dst <= imm (signed) */
++	case BPF_JMP32 | BPF_JEQ | BPF_K:
++	case BPF_JMP32 | BPF_JNE | BPF_K:
++	case BPF_JMP32 | BPF_JSET | 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:
++		if (off == 0)
++			break;
++		setup_jmp_i(ctx, imm, 32, BPF_OP(code), off, &jmp, &rel);
++		emit_sext(ctx, MIPS_R_T4, dst); /* Sign-extended dst */
++		if (valid_jmp_i(jmp, imm)) {
++			emit_jmp_i(ctx, MIPS_R_T4, imm, rel, jmp);
++		} else {
++			/* Move large immediate to register, sign-extended */
++			emit_mov_i(ctx, MIPS_R_T5, imm);
++			emit_jmp_r(ctx, MIPS_R_T4, MIPS_R_T5, rel, jmp);
++		}
++		if (finish_jmp(ctx, jmp, off) < 0)
++			goto toofar;
++		break;
++	/* PC += off if dst == src */
++	/* PC += off if dst != src */
++	/* PC += off if dst & src */
++	/* PC += off if dst > src */
++	/* PC += off if dst >= src */
++	/* PC += off if dst < src */
++	/* PC += off if dst <= src */
++	/* PC += off if dst > src (signed) */
++	/* PC += off if dst >= src (signed) */
++	/* PC += off if dst < src (signed) */
++	/* PC += off if dst <= src (signed) */
++	case BPF_JMP | BPF_JEQ | BPF_X:
++	case BPF_JMP | BPF_JNE | BPF_X:
++	case BPF_JMP | BPF_JSET | 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:
++		if (off == 0)
++			break;
++		setup_jmp_r(ctx, dst == src, BPF_OP(code), off, &jmp, &rel);
++		emit_jmp_r(ctx, dst, src, rel, jmp);
++		if (finish_jmp(ctx, jmp, off) < 0)
++			goto toofar;
++		break;
++	/* PC += off if dst == imm */
++	/* PC += off if dst != imm */
++	/* PC += off if dst & imm */
++	/* PC += off if dst > imm */
++	/* PC += off if dst >= imm */
++	/* PC += off if dst < imm */
++	/* PC += off if dst <= imm */
++	/* PC += off if dst > imm (signed) */
++	/* PC += off if dst >= imm (signed) */
++	/* PC += off if dst < imm (signed) */
++	/* PC += off if dst <= imm (signed) */
++	case BPF_JMP | BPF_JEQ | BPF_K:
++	case BPF_JMP | BPF_JNE | BPF_K:
++	case BPF_JMP | BPF_JSET | 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:
++		if (off == 0)
++			break;
++		setup_jmp_i(ctx, imm, 64, BPF_OP(code), off, &jmp, &rel);
++		if (valid_jmp_i(jmp, imm)) {
++			emit_jmp_i(ctx, dst, imm, rel, jmp);
++		} else {
++			/* Move large immediate to register */
++			emit_mov_i(ctx, MIPS_R_T4, imm);
++			emit_jmp_r(ctx, dst, MIPS_R_T4, rel, jmp);
++		}
++		if (finish_jmp(ctx, jmp, off) < 0)
++			goto toofar;
++		break;
++	/* PC += off */
++	case BPF_JMP | BPF_JA:
++		if (off == 0)
++			break;
++		if (emit_ja(ctx, off) < 0)
++			goto toofar;
++		break;
++	/* Tail call */
++	case BPF_JMP | BPF_TAIL_CALL:
++		if (emit_tail_call(ctx) < 0)
++			goto invalid;
++		break;
++	/* Function call */
++	case BPF_JMP | BPF_CALL:
++		if (emit_call(ctx, insn) < 0)
++			goto invalid;
++		break;
++	/* Function return */
++	case BPF_JMP | BPF_EXIT:
++		/*
++		 * Optimization: when last instruction is EXIT
++		 * simply continue to epilogue.
++		 */
++		if (ctx->bpf_index == ctx->program->len - 1)
++			break;
++		if (emit_exit(ctx) < 0)
++			goto toofar;
++		break;
++
++	default:
++invalid:
++		pr_err_once("unknown opcode %02x\n", code);
++		return -EINVAL;
++notyet:
++		pr_info_once("*** NOT YET: opcode %02x ***\n", code);
++		return -EFAULT;
++toofar:
++		pr_info_once("*** TOO FAR: jump at %u opcode %02x ***\n",
++			     ctx->bpf_index, code);
++		return -E2BIG;
++	}
++	return 0;
++}
diff --git a/target/linux/generic/backport-5.4/071-v5.16-04-mips-bpf-Add-JIT-workarounds-for-CPU-errata.patch b/target/linux/generic/backport-5.4/071-v5.16-04-mips-bpf-Add-JIT-workarounds-for-CPU-errata.patch
new file mode 100644
index 0000000000..63553ebe58
--- /dev/null
+++ b/target/linux/generic/backport-5.4/071-v5.16-04-mips-bpf-Add-JIT-workarounds-for-CPU-errata.patch
@@ -0,0 +1,120 @@
+From: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+Date: Tue, 5 Oct 2021 18:54:06 +0200
+Subject: [PATCH] mips: bpf: Add JIT workarounds for CPU errata
+
+This patch adds workarounds for the following CPU errata to the MIPS
+eBPF JIT, if enabled in the kernel configuration.
+
+  - R10000 ll/sc weak ordering
+  - Loongson-3 ll/sc weak ordering
+  - Loongson-2F jump hang
+
+The Loongson-2F nop errata is implemented in uasm, which the JIT uses,
+so no additional mitigations are needed for that.
+
+Signed-off-by: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+Reviewed-by: Jiaxun Yang <jiaxun.yang at flygoat.com>
+---
+
+--- a/arch/mips/net/bpf_jit_comp.c
++++ b/arch/mips/net/bpf_jit_comp.c
+@@ -404,6 +404,7 @@ void emit_alu_r(struct jit_context *ctx,
+ /* Atomic read-modify-write (32-bit) */
+ void emit_atomic_r(struct jit_context *ctx, u8 dst, u8 src, s16 off, u8 code)
+ {
++	LLSC_sync(ctx);
+ 	emit(ctx, ll, MIPS_R_T9, off, dst);
+ 	switch (code) {
+ 	case BPF_ADD:
+@@ -420,18 +421,19 @@ void emit_atomic_r(struct jit_context *c
+ 		break;
+ 	}
+ 	emit(ctx, sc, MIPS_R_T8, off, dst);
+-	emit(ctx, beqz, MIPS_R_T8, -16);
++	emit(ctx, LLSC_beqz, MIPS_R_T8, -16 - LLSC_offset);
+ 	emit(ctx, nop); /* Delay slot */
+ }
+ 
+ /* Atomic compare-and-exchange (32-bit) */
+ void emit_cmpxchg_r(struct jit_context *ctx, u8 dst, u8 src, u8 res, s16 off)
+ {
++	LLSC_sync(ctx);
+ 	emit(ctx, ll, MIPS_R_T9, off, dst);
+ 	emit(ctx, bne, MIPS_R_T9, res, 12);
+ 	emit(ctx, move, MIPS_R_T8, src);     /* Delay slot */
+ 	emit(ctx, sc, MIPS_R_T8, off, dst);
+-	emit(ctx, beqz, MIPS_R_T8, -20);
++	emit(ctx, LLSC_beqz, MIPS_R_T8, -20 - LLSC_offset);
+ 	emit(ctx, move, res, MIPS_R_T9);     /* Delay slot */
+ 	clobber_reg(ctx, res);
+ }
+--- a/arch/mips/net/bpf_jit_comp.h
++++ b/arch/mips/net/bpf_jit_comp.h
+@@ -87,7 +87,7 @@ struct jit_context {
+ };
+ 
+ /* Emit the instruction if the JIT memory space has been allocated */
+-#define emit(ctx, func, ...)					\
++#define __emit(ctx, func, ...)					\
+ do {								\
+ 	if ((ctx)->target != NULL) {				\
+ 		u32 *p = &(ctx)->target[ctx->jit_index];	\
+@@ -95,6 +95,30 @@ do {								\
+ 	}							\
+ 	(ctx)->jit_index++;					\
+ } while (0)
++#define emit(...) __emit(__VA_ARGS__)
++
++/* Workaround for R10000 ll/sc errata */
++#ifdef CONFIG_WAR_R10000
++#define LLSC_beqz	beqzl
++#else
++#define LLSC_beqz	beqz
++#endif
++
++/* Workaround for Loongson-3 ll/sc errata */
++#ifdef CONFIG_CPU_LOONGSON3_WORKAROUNDS
++#define LLSC_sync(ctx)	emit(ctx, sync, 0)
++#define LLSC_offset	4
++#else
++#define LLSC_sync(ctx)
++#define LLSC_offset	0
++#endif
++
++/* Workaround for Loongson-2F jump errata */
++#ifdef CONFIG_CPU_JUMP_WORKAROUNDS
++#define JALR_MASK	0xffffffffcfffffffULL
++#else
++#define JALR_MASK	(~0ULL)
++#endif
+ 
+ /*
+  * Mark a BPF register as accessed, it needs to be
+--- a/arch/mips/net/bpf_jit_comp64.c
++++ b/arch/mips/net/bpf_jit_comp64.c
+@@ -375,6 +375,7 @@ static void emit_atomic_r64(struct jit_c
+ 	u8 t1 = MIPS_R_T6;
+ 	u8 t2 = MIPS_R_T7;
+ 
++	LLSC_sync(ctx);
+ 	emit(ctx, lld, t1, off, dst);
+ 	switch (code) {
+ 	case BPF_ADD:
+@@ -391,7 +392,7 @@ static void emit_atomic_r64(struct jit_c
+ 		break;
+ 	}
+ 	emit(ctx, scd, t2, off, dst);
+-	emit(ctx, beqz, t2, -16);
++	emit(ctx, LLSC_beqz, t2, -16 - LLSC_offset);
+ 	emit(ctx, nop); /* Delay slot */
+ }
+ 
+@@ -414,7 +415,7 @@ static int emit_call(struct jit_context
+ 	push_regs(ctx, ctx->clobbered & JIT_CALLER_REGS, 0, 0);
+ 
+ 	/* Emit function call */
+-	emit_mov_i64(ctx, tmp, addr);
++	emit_mov_i64(ctx, tmp, addr & JALR_MASK);
+ 	emit(ctx, jalr, MIPS_R_RA, tmp);
+ 	emit(ctx, nop); /* Delay slot */
+ 
diff --git a/target/linux/generic/backport-5.4/071-v5.16-05-mips-bpf-Enable-eBPF-JITs.patch b/target/linux/generic/backport-5.4/071-v5.16-05-mips-bpf-Enable-eBPF-JITs.patch
new file mode 100644
index 0000000000..c8ce0becf9
--- /dev/null
+++ b/target/linux/generic/backport-5.4/071-v5.16-05-mips-bpf-Enable-eBPF-JITs.patch
@@ -0,0 +1,54 @@
+From: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+Date: Tue, 5 Oct 2021 18:54:07 +0200
+Subject: [PATCH] mips: bpf: Enable eBPF JITs
+
+This patch enables the new eBPF JITs for 32-bit and 64-bit MIPS. It also
+disables the old cBPF JIT to so cBPF programs are converted to use the
+new JIT.
+
+Workarounds for R4000 CPU errata are not implemented by the JIT, so the
+JIT is disabled if any of those workarounds are configured.
+
+Signed-off-by: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+---
+
+--- a/MAINTAINERS
++++ b/MAINTAINERS
+@@ -3099,6 +3099,7 @@ S:	Supported
+ F:	arch/arm64/net/
+ 
+ BPF JIT for MIPS (32-BIT AND 64-BIT)
++M:	Johan Almbladh <johan.almbladh at anyfinetworks.com>
+ M:	Paul Burton <paulburton at kernel.org>
+ L:	netdev at vger.kernel.org
+ L:	bpf at vger.kernel.org
+--- a/arch/mips/Kconfig
++++ b/arch/mips/Kconfig
+@@ -46,8 +46,10 @@ config MIPS
+ 	select HAVE_ARCH_TRACEHOOK
+ 	select HAVE_ARCH_TRANSPARENT_HUGEPAGE if CPU_SUPPORTS_HUGEPAGES
+ 	select HAVE_ASM_MODVERSIONS
+-	select HAVE_CBPF_JIT if !64BIT && !CPU_MICROMIPS
+-	select HAVE_EBPF_JIT if 64BIT && !CPU_MICROMIPS && TARGET_ISA_REV >= 2
++	select HAVE_EBPF_JIT if !CPU_MICROMIPS && \
++				!CPU_DADDI_WORKAROUNDS && \
++				!CPU_R4000_WORKAROUNDS && \
++				!CPU_R4400_WORKAROUNDS
+ 	select HAVE_CONTEXT_TRACKING
+ 	select HAVE_COPY_THREAD_TLS
+ 	select HAVE_C_RECORDMCOUNT
+--- a/arch/mips/net/Makefile
++++ b/arch/mips/net/Makefile
+@@ -2,9 +2,10 @@
+ # MIPS networking code
+ 
+ obj-$(CONFIG_MIPS_CBPF_JIT) += bpf_jit.o bpf_jit_asm.o
++obj-$(CONFIG_MIPS_EBPF_JIT) += bpf_jit_comp.o
+ 
+ ifeq ($(CONFIG_32BIT),y)
+-        obj-$(CONFIG_MIPS_EBPF_JIT) += bpf_jit_comp.o bpf_jit_comp32.o
++        obj-$(CONFIG_MIPS_EBPF_JIT) += bpf_jit_comp32.o
+ else
+-        obj-$(CONFIG_MIPS_EBPF_JIT) += ebpf_jit.o
++        obj-$(CONFIG_MIPS_EBPF_JIT) += bpf_jit_comp64.o
+ endif
diff --git a/target/linux/generic/backport-5.4/071-v5.16-06-mips-bpf-Remove-old-BPF-JIT-implementations.patch b/target/linux/generic/backport-5.4/071-v5.16-06-mips-bpf-Remove-old-BPF-JIT-implementations.patch
new file mode 100644
index 0000000000..e25c336831
--- /dev/null
+++ b/target/linux/generic/backport-5.4/071-v5.16-06-mips-bpf-Remove-old-BPF-JIT-implementations.patch
@@ -0,0 +1,387 @@
+From: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+Date: Tue, 5 Oct 2021 18:54:08 +0200
+Subject: [PATCH] mips: bpf: Remove old BPF JIT implementations
+
+This patch removes the old 32-bit cBPF and 64-bit eBPF JIT implementations.
+They are replaced by a new eBPF implementation that supports both 32-bit
+and 64-bit MIPS CPUs.
+
+Signed-off-by: Johan Almbladh <johan.almbladh at anyfinetworks.com>
+---
+ delete mode 100644 arch/mips/net/bpf_jit.c
+ delete mode 100644 arch/mips/net/bpf_jit.h
+ delete mode 100644 arch/mips/net/bpf_jit_asm.S
+ delete mode 100644 arch/mips/net/ebpf_jit.c
+
+--- a/arch/mips/net/bpf_jit.h
++++ /dev/null
+@@ -1,81 +0,0 @@
+-/* SPDX-License-Identifier: GPL-2.0-only */
+-/*
+- * Just-In-Time compiler for BPF filters on MIPS
+- *
+- * Copyright (c) 2014 Imagination Technologies Ltd.
+- * Author: Markos Chandras <markos.chandras at imgtec.com>
+- */
+-
+-#ifndef BPF_JIT_MIPS_OP_H
+-#define BPF_JIT_MIPS_OP_H
+-
+-/* Registers used by JIT */
+-#define MIPS_R_ZERO	0
+-#define MIPS_R_V0	2
+-#define MIPS_R_A0	4
+-#define MIPS_R_A1	5
+-#define MIPS_R_T4	12
+-#define MIPS_R_T5	13
+-#define MIPS_R_T6	14
+-#define MIPS_R_T7	15
+-#define MIPS_R_S0	16
+-#define MIPS_R_S1	17
+-#define MIPS_R_S2	18
+-#define MIPS_R_S3	19
+-#define MIPS_R_S4	20
+-#define MIPS_R_S5	21
+-#define MIPS_R_S6	22
+-#define MIPS_R_S7	23
+-#define MIPS_R_SP	29
+-#define MIPS_R_RA	31
+-
+-/* Conditional codes */
+-#define MIPS_COND_EQ	0x1
+-#define MIPS_COND_GE	(0x1 << 1)
+-#define MIPS_COND_GT	(0x1 << 2)
+-#define MIPS_COND_NE	(0x1 << 3)
+-#define MIPS_COND_ALL	(0x1 << 4)
+-/* Conditionals on X register or K immediate */
+-#define MIPS_COND_X	(0x1 << 5)
+-#define MIPS_COND_K	(0x1 << 6)
+-
+-#define r_ret	MIPS_R_V0
+-
+-/*
+- * Use 2 scratch registers to avoid pipeline interlocks.
+- * There is no overhead during epilogue and prologue since
+- * any of the $s0-$s6 registers will only be preserved if
+- * they are going to actually be used.
+- */
+-#define r_skb_hl	MIPS_R_S0 /* skb header length */
+-#define r_skb_data	MIPS_R_S1 /* skb actual data */
+-#define r_off		MIPS_R_S2
+-#define r_A		MIPS_R_S3
+-#define r_X		MIPS_R_S4
+-#define r_skb		MIPS_R_S5
+-#define r_M		MIPS_R_S6
+-#define r_skb_len	MIPS_R_S7
+-#define r_s0		MIPS_R_T4 /* scratch reg 1 */
+-#define r_s1		MIPS_R_T5 /* scratch reg 2 */
+-#define r_tmp_imm	MIPS_R_T6 /* No need to preserve this */
+-#define r_tmp		MIPS_R_T7 /* No need to preserve this */
+-#define r_zero		MIPS_R_ZERO
+-#define r_sp		MIPS_R_SP
+-#define r_ra		MIPS_R_RA
+-
+-#ifndef __ASSEMBLY__
+-
+-/* Declare ASM helpers */
+-
+-#define DECLARE_LOAD_FUNC(func) \
+-	extern u8 func(unsigned long *skb, int offset); \
+-	extern u8 func##_negative(unsigned long *skb, int offset); \
+-	extern u8 func##_positive(unsigned long *skb, int offset)
+-
+-DECLARE_LOAD_FUNC(sk_load_word);
+-DECLARE_LOAD_FUNC(sk_load_half);
+-DECLARE_LOAD_FUNC(sk_load_byte);
+-
+-#endif
+-
+-#endif /* BPF_JIT_MIPS_OP_H */
+--- a/arch/mips/net/bpf_jit_asm.S
++++ /dev/null
+@@ -1,285 +0,0 @@
+-/*
+- * bpf_jib_asm.S: Packet/header access helper functions for MIPS/MIPS64 BPF
+- * compiler.
+- *
+- * Copyright (C) 2015 Imagination Technologies Ltd.
+- * Author: Markos Chandras <markos.chandras at imgtec.com>
+- *
+- * This program is free software; you can redistribute it and/or modify it
+- * under the terms of the GNU General Public License as published by the
+- * Free Software Foundation; version 2 of the License.
+- */
+-
+-#include <asm/asm.h>
+-#include <asm/isa-rev.h>
+-#include <asm/regdef.h>
+-#include "bpf_jit.h"
+-
+-/* ABI
+- *
+- * r_skb_hl	skb header length
+- * r_skb_data	skb data
+- * r_off(a1)	offset register
+- * r_A		BPF register A
+- * r_X		PF register X
+- * r_skb(a0)	*skb
+- * r_M		*scratch memory
+- * r_skb_le	skb length
+- * r_s0		Scratch register 0
+- * r_s1		Scratch register 1
+- *
+- * On entry:
+- * a0: *skb
+- * a1: offset (imm or imm + X)
+- *
+- * All non-BPF-ABI registers are free for use. On return, we only
+- * care about r_ret. The BPF-ABI registers are assumed to remain
+- * unmodified during the entire filter operation.
+- */
+-
+-#define skb	a0
+-#define offset	a1
+-#define SKF_LL_OFF  (-0x200000) /* Can't include linux/filter.h in assembly */
+-
+-	/* We know better :) so prevent assembler reordering etc */
+-	.set 	noreorder
+-
+-#define is_offset_negative(TYPE)				\
+-	/* If offset is negative we have more work to do */	\
+-	slti	t0, offset, 0;					\
+-	bgtz	t0, bpf_slow_path_##TYPE##_neg;			\
+-	/* Be careful what follows in DS. */
+-
+-#define is_offset_in_header(SIZE, TYPE)				\
+-	/* Reading from header? */				\
+-	addiu	$r_s0, $r_skb_hl, -SIZE;			\
+-	slt	t0, $r_s0, offset;				\
+-	bgtz	t0, bpf_slow_path_##TYPE;			\
+-
+-LEAF(sk_load_word)
+-	is_offset_negative(word)
+-FEXPORT(sk_load_word_positive)
+-	is_offset_in_header(4, word)
+-	/* Offset within header boundaries */
+-	PTR_ADDU t1, $r_skb_data, offset
+-	.set	reorder
+-	lw	$r_A, 0(t1)
+-	.set	noreorder
+-#ifdef CONFIG_CPU_LITTLE_ENDIAN
+-# if MIPS_ISA_REV >= 2
+-	wsbh	t0, $r_A
+-	rotr	$r_A, t0, 16
+-# else
+-	sll	t0, $r_A, 24
+-	srl	t1, $r_A, 24
+-	srl	t2, $r_A, 8
+-	or	t0, t0, t1
+-	andi	t2, t2, 0xff00
+-	andi	t1, $r_A, 0xff00
+-	or	t0, t0, t2
+-	sll	t1, t1, 8
+-	or	$r_A, t0, t1
+-# endif
+-#endif
+-	jr	$r_ra
+-	 move	$r_ret, zero
+-	END(sk_load_word)
+-
+-LEAF(sk_load_half)
+-	is_offset_negative(half)
+-FEXPORT(sk_load_half_positive)
+-	is_offset_in_header(2, half)
+-	/* Offset within header boundaries */
+-	PTR_ADDU t1, $r_skb_data, offset
+-	lhu	$r_A, 0(t1)
+-#ifdef CONFIG_CPU_LITTLE_ENDIAN
+-# if MIPS_ISA_REV >= 2
+-	wsbh	$r_A, $r_A
+-# else
+-	sll	t0, $r_A, 8
+-	srl	t1, $r_A, 8
+-	andi	t0, t0, 0xff00
+-	or	$r_A, t0, t1
+-# endif
+-#endif
+-	jr	$r_ra
+-	 move	$r_ret, zero
+-	END(sk_load_half)
+-
+-LEAF(sk_load_byte)
+-	is_offset_negative(byte)
+-FEXPORT(sk_load_byte_positive)
+-	is_offset_in_header(1, byte)
+-	/* Offset within header boundaries */
+-	PTR_ADDU t1, $r_skb_data, offset
+-	lbu	$r_A, 0(t1)
+-	jr	$r_ra
+-	 move	$r_ret, zero
+-	END(sk_load_byte)
+-
+-/*
+- * call skb_copy_bits:
+- * (prototype in linux/skbuff.h)
+- *
+- * int skb_copy_bits(sk_buff *skb, int offset, void *to, int len)
+- *
+- * o32 mandates we leave 4 spaces for argument registers in case
+- * the callee needs to use them. Even though we don't care about
+- * the argument registers ourselves, we need to allocate that space
+- * to remain ABI compliant since the callee may want to use that space.
+- * We also allocate 2 more spaces for $r_ra and our return register (*to).
+- *
+- * n64 is a bit different. The *caller* will allocate the space to preserve
+- * the arguments. So in 64-bit kernels, we allocate the 4-arg space for no
+- * good reason but it does not matter that much really.
+- *
+- * (void *to) is returned in r_s0
+- *
+- */
+-#ifdef CONFIG_CPU_LITTLE_ENDIAN
+-#define DS_OFFSET(SIZE) (4 * SZREG)
+-#else
+-#define DS_OFFSET(SIZE) ((4 * SZREG) + (4 - SIZE))
+-#endif
+-#define bpf_slow_path_common(SIZE)				\
+-	/* Quick check. Are we within reasonable boundaries? */ \
+-	LONG_ADDIU	$r_s1, $r_skb_len, -SIZE;		\
+-	sltu		$r_s0, offset, $r_s1;			\
+-	beqz		$r_s0, fault;				\
+-	/* Load 4th argument in DS */				\
+-	 LONG_ADDIU	a3, zero, SIZE;				\
+-	PTR_ADDIU	$r_sp, $r_sp, -(6 * SZREG);		\
+-	PTR_LA		t0, skb_copy_bits;			\
+-	PTR_S		$r_ra, (5 * SZREG)($r_sp);		\
+-	/* Assign low slot to a2 */				\
+-	PTR_ADDIU	a2, $r_sp, DS_OFFSET(SIZE);		\
+-	jalr		t0;					\
+-	/* Reset our destination slot (DS but it's ok) */	\
+-	 INT_S		zero, (4 * SZREG)($r_sp);		\
+-	/*							\
+-	 * skb_copy_bits returns 0 on success and -EFAULT	\
+-	 * on error. Our data live in a2. Do not bother with	\
+-	 * our data if an error has been returned.		\
+-	 */							\
+-	/* Restore our frame */					\
+-	PTR_L		$r_ra, (5 * SZREG)($r_sp);		\
+-	INT_L		$r_s0, (4 * SZREG)($r_sp);		\
+-	bltz		v0, fault;				\
+-	 PTR_ADDIU	$r_sp, $r_sp, 6 * SZREG;		\
+-	move		$r_ret, zero;				\
+-
+-NESTED(bpf_slow_path_word, (6 * SZREG), $r_sp)
+-	bpf_slow_path_common(4)
+-#ifdef CONFIG_CPU_LITTLE_ENDIAN
+-# if MIPS_ISA_REV >= 2
+-	wsbh	t0, $r_s0
+-	jr	$r_ra
+-	 rotr	$r_A, t0, 16
+-# else
+-	sll	t0, $r_s0, 24
+-	srl	t1, $r_s0, 24
+-	srl	t2, $r_s0, 8
+-	or	t0, t0, t1
+-	andi	t2, t2, 0xff00
+-	andi	t1, $r_s0, 0xff00
+-	or	t0, t0, t2
+-	sll	t1, t1, 8
+-	jr	$r_ra
+-	 or	$r_A, t0, t1
+-# endif
+-#else
+-	jr	$r_ra
+-	 move	$r_A, $r_s0
+-#endif
+-
+-	END(bpf_slow_path_word)
+-
+-NESTED(bpf_slow_path_half, (6 * SZREG), $r_sp)
+-	bpf_slow_path_common(2)
+-#ifdef CONFIG_CPU_LITTLE_ENDIAN
+-# if MIPS_ISA_REV >= 2
+-	jr	$r_ra
+-	 wsbh	$r_A, $r_s0
+-# else
+-	sll	t0, $r_s0, 8
+-	andi	t1, $r_s0, 0xff00
+-	andi	t0, t0, 0xff00
+-	srl	t1, t1, 8
+-	jr	$r_ra
+-	 or	$r_A, t0, t1
+-# endif
+-#else
+-	jr	$r_ra
+-	 move	$r_A, $r_s0
+-#endif
+-
+-	END(bpf_slow_path_half)
+-
+-NESTED(bpf_slow_path_byte, (6 * SZREG), $r_sp)
+-	bpf_slow_path_common(1)
+-	jr	$r_ra
+-	 move	$r_A, $r_s0
+-
+-	END(bpf_slow_path_byte)
+-
+-/*
+- * Negative entry points
+- */
+-	.macro bpf_is_end_of_data
+-	li	t0, SKF_LL_OFF
+-	/* Reading link layer data? */
+-	slt	t1, offset, t0
+-	bgtz	t1, fault
+-	/* Be careful what follows in DS. */
+-	.endm
+-/*
+- * call skb_copy_bits:
+- * (prototype in linux/filter.h)
+- *
+- * void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb,
+- *                                            int k, unsigned int size)
+- *
+- * see above (bpf_slow_path_common) for ABI restrictions
+- */
+-#define bpf_negative_common(SIZE)					\
+-	PTR_ADDIU	$r_sp, $r_sp, -(6 * SZREG);			\
+-	PTR_LA		t0, bpf_internal_load_pointer_neg_helper;	\
+-	PTR_S		$r_ra, (5 * SZREG)($r_sp);			\
+-	jalr		t0;						\
+-	 li		a2, SIZE;					\
+-	PTR_L		$r_ra, (5 * SZREG)($r_sp);			\
+-	/* Check return pointer */					\
+-	beqz		v0, fault;					\
+-	 PTR_ADDIU	$r_sp, $r_sp, 6 * SZREG;			\
+-	/* Preserve our pointer */					\
+-	move		$r_s0, v0;					\
+-	/* Set return value */						\
+-	move		$r_ret, zero;					\
+-
+-bpf_slow_path_word_neg:
+-	bpf_is_end_of_data
+-NESTED(sk_load_word_negative, (6 * SZREG), $r_sp)
+-	bpf_negative_common(4)
+-	jr	$r_ra
+-	 lw	$r_A, 0($r_s0)
+-	END(sk_load_word_negative)
+-
+-bpf_slow_path_half_neg:
+-	bpf_is_end_of_data
+-NESTED(sk_load_half_negative, (6 * SZREG), $r_sp)
+-	bpf_negative_common(2)
+-	jr	$r_ra
+-	 lhu	$r_A, 0($r_s0)
+-	END(sk_load_half_negative)
+-
+-bpf_slow_path_byte_neg:
+-	bpf_is_end_of_data
+-NESTED(sk_load_byte_negative, (6 * SZREG), $r_sp)
+-	bpf_negative_common(1)
+-	jr	$r_ra
+-	 lbu	$r_A, 0($r_s0)
+-	END(sk_load_byte_negative)
+-
+-fault:
+-	jr	$r_ra
+-	 addiu $r_ret, zero, 1
diff --git a/target/linux/generic/backport-5.4/080-wireguard-0072-net-WireGuard-secure-network-tunnel.patch b/target/linux/generic/backport-5.4/080-wireguard-0072-net-WireGuard-secure-network-tunnel.patch
index 9e37bbb60c..a29da1e7b2 100644
--- a/target/linux/generic/backport-5.4/080-wireguard-0072-net-WireGuard-secure-network-tunnel.patch
+++ b/target/linux/generic/backport-5.4/080-wireguard-0072-net-WireGuard-secure-network-tunnel.patch
@@ -192,7 +192,7 @@ Signed-off-by: Jason A. Donenfeld <Jason at zx2c4.com>
 
 --- a/MAINTAINERS
 +++ b/MAINTAINERS
-@@ -17584,6 +17584,14 @@ L:	linux-gpio at vger.kernel.org
+@@ -17585,6 +17585,14 @@ L:	linux-gpio at vger.kernel.org
  S:	Maintained
  F:	drivers/gpio/gpio-ws16c48.c
  
diff --git a/target/linux/generic/hack-5.10/301-mips_image_cmdline_hack.patch b/target/linux/generic/hack-5.10/301-mips_image_cmdline_hack.patch
index ecf86b66a6..19b81f0301 100644
--- a/target/linux/generic/hack-5.10/301-mips_image_cmdline_hack.patch
+++ b/target/linux/generic/hack-5.10/301-mips_image_cmdline_hack.patch
@@ -10,7 +10,7 @@ Signed-off-by: Gabor Juhos <juhosg at openwrt.org>
 
 --- a/arch/mips/Kconfig
 +++ b/arch/mips/Kconfig
-@@ -1165,6 +1165,10 @@ config MIPS_MSC
+@@ -1167,6 +1167,10 @@ config MIPS_MSC
  config SYNC_R4K
  	bool
  
diff --git a/target/linux/generic/hack-5.4/301-mips_image_cmdline_hack.patch b/target/linux/generic/hack-5.4/301-mips_image_cmdline_hack.patch
index ada65cd2a0..af6b51aa4f 100644
--- a/target/linux/generic/hack-5.4/301-mips_image_cmdline_hack.patch
+++ b/target/linux/generic/hack-5.4/301-mips_image_cmdline_hack.patch
@@ -10,7 +10,7 @@ Signed-off-by: Gabor Juhos <juhosg at openwrt.org>
 
 --- a/arch/mips/Kconfig
 +++ b/arch/mips/Kconfig
-@@ -1159,6 +1159,10 @@ config SYNC_R4K
+@@ -1161,6 +1161,10 @@ config SYNC_R4K
  config MIPS_MACHINE
  	def_bool n
  
diff --git a/target/linux/generic/pending-5.10/300-mips_expose_boot_raw.patch b/target/linux/generic/pending-5.10/300-mips_expose_boot_raw.patch
index a04864ab4d..59f399d3cf 100644
--- a/target/linux/generic/pending-5.10/300-mips_expose_boot_raw.patch
+++ b/target/linux/generic/pending-5.10/300-mips_expose_boot_raw.patch
@@ -9,7 +9,7 @@ Acked-by: Rob Landley <rob at landley.net>
 ---
 --- a/arch/mips/Kconfig
 +++ b/arch/mips/Kconfig
-@@ -1080,9 +1080,6 @@ config FW_ARC
+@@ -1082,9 +1082,6 @@ config FW_ARC
  config ARCH_MAY_HAVE_PC_FDC
  	bool
  
@@ -19,7 +19,7 @@ Acked-by: Rob Landley <rob at landley.net>
  config CEVT_BCM1480
  	bool
  
-@@ -3172,6 +3169,18 @@ choice
+@@ -3174,6 +3171,18 @@ choice
  		bool "Extend builtin kernel arguments with bootloader arguments"
  endchoice
  
diff --git a/target/linux/generic/pending-5.4/103-MIPS-select-CPU_MIPS64-for-remaining-MIPS64-CPUs.patch b/target/linux/generic/pending-5.4/103-MIPS-select-CPU_MIPS64-for-remaining-MIPS64-CPUs.patch
index 4e7a532156..b5ec03f286 100644
--- a/target/linux/generic/pending-5.4/103-MIPS-select-CPU_MIPS64-for-remaining-MIPS64-CPUs.patch
+++ b/target/linux/generic/pending-5.4/103-MIPS-select-CPU_MIPS64-for-remaining-MIPS64-CPUs.patch
@@ -25,7 +25,7 @@ Signed-off-by: Jason A. Donenfeld <Jason at zx2c4.com>
 
 --- a/arch/mips/Kconfig
 +++ b/arch/mips/Kconfig
-@@ -2037,7 +2037,8 @@ config CPU_MIPS32
+@@ -2039,7 +2039,8 @@ config CPU_MIPS32
  
  config CPU_MIPS64
  	bool
diff --git a/target/linux/generic/pending-5.4/300-mips_expose_boot_raw.patch b/target/linux/generic/pending-5.4/300-mips_expose_boot_raw.patch
index 7b9ae65c60..c08d6a61f3 100644
--- a/target/linux/generic/pending-5.4/300-mips_expose_boot_raw.patch
+++ b/target/linux/generic/pending-5.4/300-mips_expose_boot_raw.patch
@@ -9,7 +9,7 @@ Acked-by: Rob Landley <rob at landley.net>
 ---
 --- a/arch/mips/Kconfig
 +++ b/arch/mips/Kconfig
-@@ -1069,9 +1069,6 @@ config FW_ARC
+@@ -1071,9 +1071,6 @@ config FW_ARC
  config ARCH_MAY_HAVE_PC_FDC
  	bool
  
@@ -19,7 +19,7 @@ Acked-by: Rob Landley <rob at landley.net>
  config CEVT_BCM1480
  	bool
  
-@@ -3044,6 +3041,18 @@ choice
+@@ -3046,6 +3043,18 @@ choice
  		bool "Extend builtin kernel arguments with bootloader arguments"
  endchoice
  
diff --git a/target/linux/ramips/patches-5.4/0122-mips-ralink-enable-zboot-support.patch b/target/linux/ramips/patches-5.4/0122-mips-ralink-enable-zboot-support.patch
index 34617898c8..4ffbb2bebb 100644
--- a/target/linux/ramips/patches-5.4/0122-mips-ralink-enable-zboot-support.patch
+++ b/target/linux/ramips/patches-5.4/0122-mips-ralink-enable-zboot-support.patch
@@ -16,7 +16,7 @@ Signed-off-by: Thomas Bogendoerfer <tsbogend at alpha.franken.de>
 
 --- a/arch/mips/Kconfig
 +++ b/arch/mips/Kconfig
-@@ -626,6 +626,7 @@ config RALINK
+@@ -628,6 +628,7 @@ config RALINK
  	select SYS_SUPPORTS_32BIT_KERNEL
  	select SYS_SUPPORTS_LITTLE_ENDIAN
  	select SYS_SUPPORTS_MIPS16



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