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-rw-r--r--arch/mips/net/ebpf_jit.c1929
1 files changed, 0 insertions, 1929 deletions
diff --git a/arch/mips/net/ebpf_jit.c b/arch/mips/net/ebpf_jit.c
deleted file mode 100644
index 46b76751f3a5..000000000000
--- a/arch/mips/net/ebpf_jit.c
+++ /dev/null
@@ -1,1929 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Just-In-Time compiler for eBPF filters on MIPS
- *
- * Copyright (c) 2017 Cavium, Inc.
- *
- * Based on code from:
- *
- * Copyright (c) 2014 Imagination Technologies Ltd.
- * Author: Markos Chandras <markos.chandras@imgtec.com>
- */
-
-#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/byteorder.h>
-#include <asm/cacheflush.h>
-#include <asm/cpu-features.h>
-#include <asm/isa-rev.h>
-#include <asm/uasm.h>
-
-/* Registers used by JIT */
-#define MIPS_R_ZERO 0
-#define MIPS_R_AT 1
-#define MIPS_R_V0 2 /* BPF_R0 */
-#define MIPS_R_V1 3
-#define MIPS_R_A0 4 /* BPF_R1 */
-#define MIPS_R_A1 5 /* BPF_R2 */
-#define MIPS_R_A2 6 /* BPF_R3 */
-#define MIPS_R_A3 7 /* BPF_R4 */
-#define MIPS_R_A4 8 /* BPF_R5 */
-#define MIPS_R_T4 12 /* BPF_AX */
-#define MIPS_R_T5 13
-#define MIPS_R_T6 14
-#define MIPS_R_T7 15
-#define MIPS_R_S0 16 /* BPF_R6 */
-#define MIPS_R_S1 17 /* BPF_R7 */
-#define MIPS_R_S2 18 /* BPF_R8 */
-#define MIPS_R_S3 19 /* BPF_R9 */
-#define MIPS_R_S4 20 /* BPF_TCC */
-#define MIPS_R_S5 21
-#define MIPS_R_S6 22
-#define MIPS_R_S7 23
-#define MIPS_R_T8 24
-#define MIPS_R_T9 25
-#define MIPS_R_SP 29
-#define MIPS_R_RA 31
-
-/* eBPF flags */
-#define EBPF_SAVE_S0 BIT(0)
-#define EBPF_SAVE_S1 BIT(1)
-#define EBPF_SAVE_S2 BIT(2)
-#define EBPF_SAVE_S3 BIT(3)
-#define EBPF_SAVE_S4 BIT(4)
-#define EBPF_SAVE_RA BIT(5)
-#define EBPF_SEEN_FP BIT(6)
-#define EBPF_SEEN_TC BIT(7)
-#define EBPF_TCC_IN_V1 BIT(8)
-
-/*
- * For the mips64 ISA, we need to track the value range or type for
- * each JIT register. The BPF machine requires zero extended 32-bit
- * values, but the mips64 ISA requires sign extended 32-bit values.
- * At each point in the BPF program we track the state of every
- * register so that we can zero extend or sign extend as the BPF
- * semantics require.
- */
-enum reg_val_type {
- /* uninitialized */
- REG_UNKNOWN,
- /* not known to be 32-bit compatible. */
- REG_64BIT,
- /* 32-bit compatible, no truncation needed for 64-bit ops. */
- REG_64BIT_32BIT,
- /* 32-bit compatible, need truncation for 64-bit ops. */
- REG_32BIT,
- /* 32-bit no sign/zero extension needed. */
- REG_32BIT_POS
-};
-
-/*
- * high bit of offsets indicates if long branch conversion done at
- * this insn.
- */
-#define OFFSETS_B_CONV BIT(31)
-
-/**
- * struct jit_ctx - JIT context
- * @skf: The sk_filter
- * @stack_size: eBPF stack size
- * @idx: Instruction index
- * @flags: JIT flags
- * @offsets: Instruction offsets
- * @target: Memory location for the compiled filter
- * @reg_val_types Packed enum reg_val_type for each register.
- */
-struct jit_ctx {
- const struct bpf_prog *skf;
- int stack_size;
- u32 idx;
- u32 flags;
- u32 *offsets;
- u32 *target;
- u64 *reg_val_types;
- unsigned int long_b_conversion:1;
- unsigned int gen_b_offsets:1;
- unsigned int use_bbit_insns:1;
-};
-
-static void set_reg_val_type(u64 *rvt, int reg, enum reg_val_type type)
-{
- *rvt &= ~(7ull << (reg * 3));
- *rvt |= ((u64)type << (reg * 3));
-}
-
-static enum reg_val_type get_reg_val_type(const struct jit_ctx *ctx,
- int index, int reg)
-{
- return (ctx->reg_val_types[index] >> (reg * 3)) & 7;
-}
-
-/* Simply emit the instruction if the JIT memory space has been allocated */
-#define emit_instr_long(ctx, func64, func32, ...) \
-do { \
- if ((ctx)->target != NULL) { \
- u32 *p = &(ctx)->target[ctx->idx]; \
- if (IS_ENABLED(CONFIG_64BIT)) \
- uasm_i_##func64(&p, ##__VA_ARGS__); \
- else \
- uasm_i_##func32(&p, ##__VA_ARGS__); \
- } \
- (ctx)->idx++; \
-} while (0)
-
-#define emit_instr(ctx, func, ...) \
- emit_instr_long(ctx, func, func, ##__VA_ARGS__)
-
-static unsigned int j_target(struct jit_ctx *ctx, int target_idx)
-{
- unsigned long target_va, base_va;
- unsigned int r;
-
- if (!ctx->target)
- return 0;
-
- base_va = (unsigned long)ctx->target;
- target_va = base_va + (ctx->offsets[target_idx] & ~OFFSETS_B_CONV);
-
- if ((base_va & ~0x0ffffffful) != (target_va & ~0x0ffffffful))
- return (unsigned int)-1;
- r = target_va & 0x0ffffffful;
- return r;
-}
-
-/* Compute the immediate value for PC-relative branches. */
-static u32 b_imm(unsigned int tgt, struct jit_ctx *ctx)
-{
- if (!ctx->gen_b_offsets)
- return 0;
-
- /*
- * We want a pc-relative branch. tgt is the instruction offset
- * we want to jump to.
-
- * Branch on MIPS:
- * I: target_offset <- sign_extend(offset)
- * I+1: PC += target_offset (delay slot)
- *
- * ctx->idx currently points to the branch instruction
- * but the offset is added to the delay slot so we need
- * to subtract 4.
- */
- return (ctx->offsets[tgt] & ~OFFSETS_B_CONV) -
- (ctx->idx * 4) - 4;
-}
-
-enum which_ebpf_reg {
- src_reg,
- src_reg_no_fp,
- dst_reg,
- dst_reg_fp_ok
-};
-
-/*
- * For eBPF, the register mapping naturally falls out of the
- * requirements of eBPF and the MIPS n64 ABI. We don't maintain a
- * separate frame pointer, so BPF_REG_10 relative accesses are
- * adjusted to be $sp relative.
- */
-static int ebpf_to_mips_reg(struct jit_ctx *ctx,
- const struct bpf_insn *insn,
- enum which_ebpf_reg w)
-{
- int ebpf_reg = (w == src_reg || w == src_reg_no_fp) ?
- insn->src_reg : insn->dst_reg;
-
- switch (ebpf_reg) {
- case BPF_REG_0:
- return MIPS_R_V0;
- case BPF_REG_1:
- return MIPS_R_A0;
- case BPF_REG_2:
- return MIPS_R_A1;
- case BPF_REG_3:
- return MIPS_R_A2;
- case BPF_REG_4:
- return MIPS_R_A3;
- case BPF_REG_5:
- return MIPS_R_A4;
- case BPF_REG_6:
- ctx->flags |= EBPF_SAVE_S0;
- return MIPS_R_S0;
- case BPF_REG_7:
- ctx->flags |= EBPF_SAVE_S1;
- return MIPS_R_S1;
- case BPF_REG_8:
- ctx->flags |= EBPF_SAVE_S2;
- return MIPS_R_S2;
- case BPF_REG_9:
- ctx->flags |= EBPF_SAVE_S3;
- return MIPS_R_S3;
- case BPF_REG_10:
- if (w == dst_reg || w == src_reg_no_fp)
- goto bad_reg;
- ctx->flags |= EBPF_SEEN_FP;
- /*
- * Needs special handling, return something that
- * cannot be clobbered just in case.
- */
- return MIPS_R_ZERO;
- case BPF_REG_AX:
- return MIPS_R_T4;
- default:
-bad_reg:
- WARN(1, "Illegal bpf reg: %d\n", ebpf_reg);
- return -EINVAL;
- }
-}
-/*
- * eBPF stack frame will be something like:
- *
- * Entry $sp ------> +--------------------------------+
- * | $ra (optional) |
- * +--------------------------------+
- * | $s0 (optional) |
- * +--------------------------------+
- * | $s1 (optional) |
- * +--------------------------------+
- * | $s2 (optional) |
- * +--------------------------------+
- * | $s3 (optional) |
- * +--------------------------------+
- * | $s4 (optional) |
- * +--------------------------------+
- * | tmp-storage (if $ra saved) |
- * $sp + tmp_offset --> +--------------------------------+ <--BPF_REG_10
- * | BPF_REG_10 relative storage |
- * | MAX_BPF_STACK (optional) |
- * | . |
- * | . |
- * | . |
- * $sp --------> +--------------------------------+
- *
- * If BPF_REG_10 is never referenced, then the MAX_BPF_STACK sized
- * area is not allocated.
- */
-static int gen_int_prologue(struct jit_ctx *ctx)
-{
- int stack_adjust = 0;
- int store_offset;
- int locals_size;
-
- if (ctx->flags & EBPF_SAVE_RA)
- /*
- * If RA we are doing a function call and may need
- * extra 8-byte tmp area.
- */
- stack_adjust += 2 * sizeof(long);
- if (ctx->flags & EBPF_SAVE_S0)
- stack_adjust += sizeof(long);
- if (ctx->flags & EBPF_SAVE_S1)
- stack_adjust += sizeof(long);
- if (ctx->flags & EBPF_SAVE_S2)
- stack_adjust += sizeof(long);
- if (ctx->flags & EBPF_SAVE_S3)
- stack_adjust += sizeof(long);
- if (ctx->flags & EBPF_SAVE_S4)
- stack_adjust += sizeof(long);
-
- BUILD_BUG_ON(MAX_BPF_STACK & 7);
- locals_size = (ctx->flags & EBPF_SEEN_FP) ? MAX_BPF_STACK : 0;
-
- stack_adjust += locals_size;
-
- ctx->stack_size = stack_adjust;
-
- /*
- * First instruction initializes the tail call count (TCC).
- * On tail call we skip this instruction, and the TCC is
- * passed in $v1 from the caller.
- */
- emit_instr(ctx, addiu, MIPS_R_V1, MIPS_R_ZERO, MAX_TAIL_CALL_CNT);
- if (stack_adjust)
- emit_instr_long(ctx, daddiu, addiu,
- MIPS_R_SP, MIPS_R_SP, -stack_adjust);
- else
- return 0;
-
- store_offset = stack_adjust - sizeof(long);
-
- if (ctx->flags & EBPF_SAVE_RA) {
- emit_instr_long(ctx, sd, sw,
- MIPS_R_RA, store_offset, MIPS_R_SP);
- store_offset -= sizeof(long);
- }
- if (ctx->flags & EBPF_SAVE_S0) {
- emit_instr_long(ctx, sd, sw,
- MIPS_R_S0, store_offset, MIPS_R_SP);
- store_offset -= sizeof(long);
- }
- if (ctx->flags & EBPF_SAVE_S1) {
- emit_instr_long(ctx, sd, sw,
- MIPS_R_S1, store_offset, MIPS_R_SP);
- store_offset -= sizeof(long);
- }
- if (ctx->flags & EBPF_SAVE_S2) {
- emit_instr_long(ctx, sd, sw,
- MIPS_R_S2, store_offset, MIPS_R_SP);
- store_offset -= sizeof(long);
- }
- if (ctx->flags & EBPF_SAVE_S3) {
- emit_instr_long(ctx, sd, sw,
- MIPS_R_S3, store_offset, MIPS_R_SP);
- store_offset -= sizeof(long);
- }
- if (ctx->flags & EBPF_SAVE_S4) {
- emit_instr_long(ctx, sd, sw,
- MIPS_R_S4, store_offset, MIPS_R_SP);
- store_offset -= sizeof(long);
- }
-
- if ((ctx->flags & EBPF_SEEN_TC) && !(ctx->flags & EBPF_TCC_IN_V1))
- emit_instr_long(ctx, daddu, addu,
- MIPS_R_S4, MIPS_R_V1, MIPS_R_ZERO);
-
- return 0;
-}
-
-static int build_int_epilogue(struct jit_ctx *ctx, int dest_reg)
-{
- const struct bpf_prog *prog = ctx->skf;
- int stack_adjust = ctx->stack_size;
- int store_offset = stack_adjust - sizeof(long);
- enum reg_val_type td;
- int r0 = MIPS_R_V0;
-
- if (dest_reg == MIPS_R_RA) {
- /* Don't let zero extended value escape. */
- td = get_reg_val_type(ctx, prog->len, BPF_REG_0);
- if (td == REG_64BIT)
- emit_instr(ctx, sll, r0, r0, 0);
- }
-
- if (ctx->flags & EBPF_SAVE_RA) {
- emit_instr_long(ctx, ld, lw,
- MIPS_R_RA, store_offset, MIPS_R_SP);
- store_offset -= sizeof(long);
- }
- if (ctx->flags & EBPF_SAVE_S0) {
- emit_instr_long(ctx, ld, lw,
- MIPS_R_S0, store_offset, MIPS_R_SP);
- store_offset -= sizeof(long);
- }
- if (ctx->flags & EBPF_SAVE_S1) {
- emit_instr_long(ctx, ld, lw,
- MIPS_R_S1, store_offset, MIPS_R_SP);
- store_offset -= sizeof(long);
- }
- if (ctx->flags & EBPF_SAVE_S2) {
- emit_instr_long(ctx, ld, lw,
- MIPS_R_S2, store_offset, MIPS_R_SP);
- store_offset -= sizeof(long);
- }
- if (ctx->flags & EBPF_SAVE_S3) {
- emit_instr_long(ctx, ld, lw,
- MIPS_R_S3, store_offset, MIPS_R_SP);
- store_offset -= sizeof(long);
- }
- if (ctx->flags & EBPF_SAVE_S4) {
- emit_instr_long(ctx, ld, lw,
- MIPS_R_S4, store_offset, MIPS_R_SP);
- store_offset -= sizeof(long);
- }
- emit_instr(ctx, jr, dest_reg);
-
- if (stack_adjust)
- emit_instr_long(ctx, daddiu, addiu,
- MIPS_R_SP, MIPS_R_SP, stack_adjust);
- else
- emit_instr(ctx, nop);
-
- return 0;
-}
-
-static void gen_imm_to_reg(const struct bpf_insn *insn, int reg,
- struct jit_ctx *ctx)
-{
- if (insn->imm >= S16_MIN && insn->imm <= S16_MAX) {
- emit_instr(ctx, addiu, reg, MIPS_R_ZERO, insn->imm);
- } else {
- int lower = (s16)(insn->imm & 0xffff);
- int upper = insn->imm - lower;
-
- emit_instr(ctx, lui, reg, upper >> 16);
- emit_instr(ctx, addiu, reg, reg, lower);
- }
-}
-
-static int gen_imm_insn(const struct bpf_insn *insn, struct jit_ctx *ctx,
- int idx)
-{
- int upper_bound, lower_bound;
- int dst = ebpf_to_mips_reg(ctx, insn, dst_reg);
-
- if (dst < 0)
- return dst;
-
- switch (BPF_OP(insn->code)) {
- case BPF_MOV:
- case BPF_ADD:
- upper_bound = S16_MAX;
- lower_bound = S16_MIN;
- break;
- case BPF_SUB:
- upper_bound = -(int)S16_MIN;
- lower_bound = -(int)S16_MAX;
- break;
- case BPF_AND:
- case BPF_OR:
- case BPF_XOR:
- upper_bound = 0xffff;
- lower_bound = 0;
- break;
- case BPF_RSH:
- case BPF_LSH:
- case BPF_ARSH:
- /* Shift amounts are truncated, no need for bounds */
- upper_bound = S32_MAX;
- lower_bound = S32_MIN;
- break;
- default:
- return -EINVAL;
- }
-
- /*
- * Immediate move clobbers the register, so no sign/zero
- * extension needed.
- */
- if (BPF_CLASS(insn->code) == BPF_ALU64 &&
- BPF_OP(insn->code) != BPF_MOV &&
- get_reg_val_type(ctx, idx, insn->dst_reg) == REG_32BIT)
- emit_instr(ctx, dinsu, dst, MIPS_R_ZERO, 32, 32);
- /* BPF_ALU | BPF_LSH doesn't need separate sign extension */
- if (BPF_CLASS(insn->code) == BPF_ALU &&
- BPF_OP(insn->code) != BPF_LSH &&
- BPF_OP(insn->code) != BPF_MOV &&
- get_reg_val_type(ctx, idx, insn->dst_reg) != REG_32BIT)
- emit_instr(ctx, sll, dst, dst, 0);
-
- if (insn->imm >= lower_bound && insn->imm <= upper_bound) {
- /* single insn immediate case */
- switch (BPF_OP(insn->code) | BPF_CLASS(insn->code)) {
- case BPF_ALU64 | BPF_MOV:
- emit_instr(ctx, daddiu, dst, MIPS_R_ZERO, insn->imm);
- break;
- case BPF_ALU64 | BPF_AND:
- case BPF_ALU | BPF_AND:
- emit_instr(ctx, andi, dst, dst, insn->imm);
- break;
- case BPF_ALU64 | BPF_OR:
- case BPF_ALU | BPF_OR:
- emit_instr(ctx, ori, dst, dst, insn->imm);
- break;
- case BPF_ALU64 | BPF_XOR:
- case BPF_ALU | BPF_XOR:
- emit_instr(ctx, xori, dst, dst, insn->imm);
- break;
- case BPF_ALU64 | BPF_ADD:
- emit_instr(ctx, daddiu, dst, dst, insn->imm);
- break;
- case BPF_ALU64 | BPF_SUB:
- emit_instr(ctx, daddiu, dst, dst, -insn->imm);
- break;
- case BPF_ALU64 | BPF_RSH:
- emit_instr(ctx, dsrl_safe, dst, dst, insn->imm & 0x3f);
- break;
- case BPF_ALU | BPF_RSH:
- emit_instr(ctx, srl, dst, dst, insn->imm & 0x1f);
- break;
- case BPF_ALU64 | BPF_LSH:
- emit_instr(ctx, dsll_safe, dst, dst, insn->imm & 0x3f);
- break;
- case BPF_ALU | BPF_LSH:
- emit_instr(ctx, sll, dst, dst, insn->imm & 0x1f);
- break;
- case BPF_ALU64 | BPF_ARSH:
- emit_instr(ctx, dsra_safe, dst, dst, insn->imm & 0x3f);
- break;
- case BPF_ALU | BPF_ARSH:
- emit_instr(ctx, sra, dst, dst, insn->imm & 0x1f);
- break;
- case BPF_ALU | BPF_MOV:
- emit_instr(ctx, addiu, dst, MIPS_R_ZERO, insn->imm);
- break;
- case BPF_ALU | BPF_ADD:
- emit_instr(ctx, addiu, dst, dst, insn->imm);
- break;
- case BPF_ALU | BPF_SUB:
- emit_instr(ctx, addiu, dst, dst, -insn->imm);
- break;
- default:
- return -EINVAL;
- }
- } else {
- /* multi insn immediate case */
- if (BPF_OP(insn->code) == BPF_MOV) {
- gen_imm_to_reg(insn, dst, ctx);
- } else {
- gen_imm_to_reg(insn, MIPS_R_AT, ctx);
- switch (BPF_OP(insn->code) | BPF_CLASS(insn->code)) {
- case BPF_ALU64 | BPF_AND:
- case BPF_ALU | BPF_AND:
- emit_instr(ctx, and, dst, dst, MIPS_R_AT);
- break;
- case BPF_ALU64 | BPF_OR:
- case BPF_ALU | BPF_OR:
- emit_instr(ctx, or, dst, dst, MIPS_R_AT);
- break;
- case BPF_ALU64 | BPF_XOR:
- case BPF_ALU | BPF_XOR:
- emit_instr(ctx, xor, dst, dst, MIPS_R_AT);
- break;
- case BPF_ALU64 | BPF_ADD:
- emit_instr(ctx, daddu, dst, dst, MIPS_R_AT);
- break;
- case BPF_ALU64 | BPF_SUB:
- emit_instr(ctx, dsubu, dst, dst, MIPS_R_AT);
- break;
- case BPF_ALU | BPF_ADD:
- emit_instr(ctx, addu, dst, dst, MIPS_R_AT);
- break;
- case BPF_ALU | BPF_SUB:
- emit_instr(ctx, subu, dst, dst, MIPS_R_AT);
- break;
- default:
- return -EINVAL;
- }
- }
- }
-
- return 0;
-}
-
-static void emit_const_to_reg(struct jit_ctx *ctx, int dst, u64 value)
-{
- if (value >= 0xffffffffffff8000ull || value < 0x8000ull) {
- emit_instr(ctx, daddiu, dst, MIPS_R_ZERO, (int)value);
- } else if (value >= 0xffffffff80000000ull ||
- (value < 0x80000000 && value > 0xffff)) {
- emit_instr(ctx, lui, dst, (s32)(s16)(value >> 16));
- emit_instr(ctx, ori, dst, dst, (unsigned int)(value & 0xffff));
- } else {
- int i;
- bool seen_part = false;
- int needed_shift = 0;
-
- for (i = 0; i < 4; i++) {
- u64 part = (value >> (16 * (3 - i))) & 0xffff;
-
- if (seen_part && needed_shift > 0 && (part || i == 3)) {
- emit_instr(ctx, dsll_safe, dst, dst, needed_shift);
- needed_shift = 0;
- }
- if (part) {
- if (i == 0 || (!seen_part && i < 3 && part < 0x8000)) {
- emit_instr(ctx, lui, dst, (s32)(s16)part);
- needed_shift = -16;
- } else {
- emit_instr(ctx, ori, dst,
- seen_part ? dst : MIPS_R_ZERO,
- (unsigned int)part);
- }
- seen_part = true;
- }
- if (seen_part)
- needed_shift += 16;
- }
- }
-}
-
-static int emit_bpf_tail_call(struct jit_ctx *ctx, int this_idx)
-{
- int off, b_off;
-
- ctx->flags |= EBPF_SEEN_TC;
- /*
- * if (index >= array->map.max_entries)
- * goto out;
- */
- off = offsetof(struct bpf_array, map.max_entries);
- emit_instr(ctx, lwu, MIPS_R_T5, off, MIPS_R_A1);
- emit_instr(ctx, sltu, MIPS_R_AT, MIPS_R_T5, MIPS_R_A2);
- b_off = b_imm(this_idx + 1, ctx);
- emit_instr(ctx, bne, MIPS_R_AT, MIPS_R_ZERO, b_off);
- /*
- * if (--TCC < 0)
- * goto out;
- */
- /* Delay slot */
- emit_instr(ctx, daddiu, MIPS_R_T5,
- (ctx->flags & EBPF_TCC_IN_V1) ? MIPS_R_V1 : MIPS_R_S4, -1);
- b_off = b_imm(this_idx + 1, ctx);
- emit_instr(ctx, bltz, MIPS_R_T5, b_off);
- /*
- * prog = array->ptrs[index];
- * if (prog == NULL)
- * goto out;
- */
- /* Delay slot */
- emit_instr(ctx, dsll, MIPS_R_T8, MIPS_R_A2, 3);
- emit_instr(ctx, daddu, MIPS_R_T8, MIPS_R_T8, MIPS_R_A1);
- off = offsetof(struct bpf_array, ptrs);
- emit_instr(ctx, ld, MIPS_R_AT, off, MIPS_R_T8);
- b_off = b_imm(this_idx + 1, ctx);
- emit_instr(ctx, beq, MIPS_R_AT, MIPS_R_ZERO, b_off);
- /* Delay slot */
- emit_instr(ctx, nop);
-
- /* goto *(prog->bpf_func + 4); */
- off = offsetof(struct bpf_prog, bpf_func);
- emit_instr(ctx, ld, MIPS_R_T9, off, MIPS_R_AT);
- /* All systems are go... propagate TCC */
- emit_instr(ctx, daddu, MIPS_R_V1, MIPS_R_T5, MIPS_R_ZERO);
- /* Skip first instruction (TCC initialization) */
- emit_instr(ctx, daddiu, MIPS_R_T9, MIPS_R_T9, 4);
- return build_int_epilogue(ctx, MIPS_R_T9);
-}
-
-static bool is_bad_offset(int b_off)
-{
- return b_off > 0x1ffff || b_off < -0x20000;
-}
-
-/* Returns the number of insn slots consumed. */
-static int build_one_insn(const struct bpf_insn *insn, struct jit_ctx *ctx,
- int this_idx, int exit_idx)
-{
- int src, dst, r, td, ts, mem_off, b_off;
- bool need_swap, did_move, cmp_eq;
- unsigned int target = 0;
- u64 t64;
- s64 t64s;
- int bpf_op = BPF_OP(insn->code);
-
- if (IS_ENABLED(CONFIG_32BIT) && ((BPF_CLASS(insn->code) == BPF_ALU64)
- || (bpf_op == BPF_DW)))
- return -EINVAL;
-
- switch (insn->code) {
- case BPF_ALU64 | BPF_ADD | BPF_K: /* ALU64_IMM */
- case BPF_ALU64 | BPF_SUB | BPF_K: /* ALU64_IMM */
- case BPF_ALU64 | BPF_OR | BPF_K: /* ALU64_IMM */
- case BPF_ALU64 | BPF_AND | BPF_K: /* ALU64_IMM */
- case BPF_ALU64 | BPF_LSH | BPF_K: /* ALU64_IMM */
- case BPF_ALU64 | BPF_RSH | BPF_K: /* ALU64_IMM */
- case BPF_ALU64 | BPF_XOR | BPF_K: /* ALU64_IMM */
- case BPF_ALU64 | BPF_ARSH | BPF_K: /* ALU64_IMM */
- case BPF_ALU64 | BPF_MOV | BPF_K: /* ALU64_IMM */
- case BPF_ALU | BPF_MOV | BPF_K: /* ALU32_IMM */
- case BPF_ALU | BPF_ADD | BPF_K: /* ALU32_IMM */
- case BPF_ALU | BPF_SUB | BPF_K: /* ALU32_IMM */
- case BPF_ALU | BPF_OR | BPF_K: /* ALU64_IMM */
- case BPF_ALU | BPF_AND | BPF_K: /* ALU64_IMM */
- case BPF_ALU | BPF_LSH | BPF_K: /* ALU64_IMM */
- case BPF_ALU | BPF_RSH | BPF_K: /* ALU64_IMM */
- case BPF_ALU | BPF_XOR | BPF_K: /* ALU64_IMM */
- case BPF_ALU | BPF_ARSH | BPF_K: /* ALU64_IMM */
- r = gen_imm_insn(insn, ctx, this_idx);
- if (r < 0)
- return r;
- break;
- case BPF_ALU64 | BPF_MUL | BPF_K: /* ALU64_IMM */
- dst = ebpf_to_mips_reg(ctx, insn, dst_reg);
- if (dst < 0)
- return dst;
- if (get_reg_val_type(ctx, this_idx, insn->dst_reg) == REG_32BIT)
- emit_instr(ctx, dinsu, dst, MIPS_R_ZERO, 32, 32);
- if (insn->imm == 1) /* Mult by 1 is a nop */
- break;
- gen_imm_to_reg(insn, MIPS_R_AT, ctx);
- if (MIPS_ISA_REV >= 6) {
- emit_instr(ctx, dmulu, dst, dst, MIPS_R_AT);
- } else {
- emit_instr(ctx, dmultu, MIPS_R_AT, dst);
- emit_instr(ctx, mflo, dst);
- }
- break;
- case BPF_ALU64 | BPF_NEG | BPF_K: /* ALU64_IMM */
- dst = ebpf_to_mips_reg(ctx, insn, dst_reg);
- if (dst < 0)
- return dst;
- if (get_reg_val_type(ctx, this_idx, insn->dst_reg) == REG_32BIT)
- emit_instr(ctx, dinsu, dst, MIPS_R_ZERO, 32, 32);
- emit_instr(ctx, dsubu, dst, MIPS_R_ZERO, dst);
- break;
- case BPF_ALU | BPF_MUL | BPF_K: /* ALU_IMM */
- dst = ebpf_to_mips_reg(ctx, insn, dst_reg);
- if (dst < 0)
- return dst;
- td = get_reg_val_type(ctx, this_idx, insn->dst_reg);
- if (td == REG_64BIT) {
- /* sign extend */
- emit_instr(ctx, sll, dst, dst, 0);
- }
- if (insn->imm == 1) /* Mult by 1 is a nop */
- break;
- gen_imm_to_reg(insn, MIPS_R_AT, ctx);
- if (MIPS_ISA_REV >= 6) {
- emit_instr(ctx, mulu, dst, dst, MIPS_R_AT);
- } else {
- emit_instr(ctx, multu, dst, MIPS_R_AT);
- emit_instr(ctx, mflo, dst);
- }
- break;
- case BPF_ALU | BPF_NEG | BPF_K: /* ALU_IMM */
- dst = ebpf_to_mips_reg(ctx, insn, dst_reg);
- if (dst < 0)
- return dst;
- td = get_reg_val_type(ctx, this_idx, insn->dst_reg);
- if (td == REG_64BIT) {
- /* sign extend */
- emit_instr(ctx, sll, dst, dst, 0);
- }
- emit_instr(ctx, subu, dst, MIPS_R_ZERO, dst);
- break;
- case BPF_ALU | BPF_DIV | BPF_K: /* ALU_IMM */
- case BPF_ALU | BPF_MOD | BPF_K: /* ALU_IMM */
- if (insn->imm == 0)
- return -EINVAL;
- dst = ebpf_to_mips_reg(ctx, insn, dst_reg);
- if (dst < 0)
- return dst;
- td = get_reg_val_type(ctx, this_idx, insn->dst_reg);
- if (td == REG_64BIT)
- /* sign extend */
- emit_instr(ctx, sll, dst, dst, 0);
- if (insn->imm == 1) {
- /* div by 1 is a nop, mod by 1 is zero */
- if (bpf_op == BPF_MOD)
- emit_instr(ctx, addu, dst, MIPS_R_ZERO, MIPS_R_ZERO);
- break;
- }
- gen_imm_to_reg(insn, MIPS_R_AT, ctx);
- if (MIPS_ISA_REV >= 6) {
- if (bpf_op == BPF_DIV)
- emit_instr(ctx, divu_r6, dst, dst, MIPS_R_AT);
- else
- emit_instr(ctx, modu, dst, dst, MIPS_R_AT);
- break;
- }
- emit_instr(ctx, divu, dst, MIPS_R_AT);
- if (bpf_op == BPF_DIV)
- emit_instr(ctx, mflo, dst);
- else
- emit_instr(ctx, mfhi, dst);
- break;
- case BPF_ALU64 | BPF_DIV | BPF_K: /* ALU_IMM */
- case BPF_ALU64 | BPF_MOD | BPF_K: /* ALU_IMM */
- if (insn->imm == 0)
- return -EINVAL;
- dst = ebpf_to_mips_reg(ctx, insn, dst_reg);
- if (dst < 0)
- return dst;
- if (get_reg_val_type(ctx, this_idx, insn->dst_reg) == REG_32BIT)
- emit_instr(ctx, dinsu, dst, MIPS_R_ZERO, 32, 32);
- if (insn->imm == 1) {
- /* div by 1 is a nop, mod by 1 is zero */
- if (bpf_op == BPF_MOD)
- emit_instr(ctx, addu, dst, MIPS_R_ZERO, MIPS_R_ZERO);
- break;
- }
- gen_imm_to_reg(insn, MIPS_R_AT, ctx);
- if (MIPS_ISA_REV >= 6) {
- if (bpf_op == BPF_DIV)
- emit_instr(ctx, ddivu_r6, dst, dst, MIPS_R_AT);
- else
- emit_instr(ctx, modu, dst, dst, MIPS_R_AT);
- break;
- }
- emit_instr(ctx, ddivu, dst, MIPS_R_AT);
- if (bpf_op == BPF_DIV)
- emit_instr(ctx, mflo, dst);
- else
- emit_instr(ctx, mfhi, dst);
- break;
- case BPF_ALU64 | BPF_MOV | BPF_X: /* ALU64_REG */
- case BPF_ALU64 | BPF_ADD | BPF_X: /* ALU64_REG */
- case BPF_ALU64 | BPF_SUB | BPF_X: /* ALU64_REG */
- case BPF_ALU64 | BPF_XOR | BPF_X: /* ALU64_REG */
- case BPF_ALU64 | BPF_OR | BPF_X: /* ALU64_REG */
- case BPF_ALU64 | BPF_AND | BPF_X: /* ALU64_REG */
- case BPF_ALU64 | BPF_MUL | BPF_X: /* ALU64_REG */
- case BPF_ALU64 | BPF_DIV | BPF_X: /* ALU64_REG */
- case BPF_ALU64 | BPF_MOD | BPF_X: /* ALU64_REG */
- case BPF_ALU64 | BPF_LSH | BPF_X: /* ALU64_REG */
- case BPF_ALU64 | BPF_RSH | BPF_X: /* ALU64_REG */
- case BPF_ALU64 | BPF_ARSH | BPF_X: /* ALU64_REG */
- src = ebpf_to_mips_reg(ctx, insn, src_reg);
- dst = ebpf_to_mips_reg(ctx, insn, dst_reg);
- if (src < 0 || dst < 0)
- return -EINVAL;
- if (get_reg_val_type(ctx, this_idx, insn->dst_reg) == REG_32BIT)
- emit_instr(ctx, dinsu, dst, MIPS_R_ZERO, 32, 32);
- did_move = false;
- if (insn->src_reg == BPF_REG_10) {
- if (bpf_op == BPF_MOV) {
- emit_instr(ctx, daddiu, dst, MIPS_R_SP, MAX_BPF_STACK);
- did_move = true;
- } else {
- emit_instr(ctx, daddiu, MIPS_R_AT, MIPS_R_SP, MAX_BPF_STACK);
- src = MIPS_R_AT;
- }
- } else if (get_reg_val_type(ctx, this_idx, insn->src_reg) == REG_32BIT) {
- int tmp_reg = MIPS_R_AT;
-
- if (bpf_op == BPF_MOV) {
- tmp_reg = dst;
- did_move = true;
- }
- emit_instr(ctx, daddu, tmp_reg, src, MIPS_R_ZERO);
- emit_instr(ctx, dinsu, tmp_reg, MIPS_R_ZERO, 32, 32);
- src = MIPS_R_AT;
- }
- switch (bpf_op) {
- case BPF_MOV:
- if (!did_move)
- emit_instr(ctx, daddu, dst, src, MIPS_R_ZERO);
- break;
- case BPF_ADD:
- emit_instr(ctx, daddu, dst, dst, src);
- break;
- case BPF_SUB:
- emit_instr(ctx, dsubu, dst, dst, src);
- break;
- case BPF_XOR:
- emit_instr(ctx, xor, dst, dst, src);
- break;
- case BPF_OR:
- emit_instr(ctx, or, dst, dst, src);
- break;
- case BPF_AND:
- emit_instr(ctx, and, dst, dst, src);
- break;
- case BPF_MUL:
- if (MIPS_ISA_REV >= 6) {
- emit_instr(ctx, dmulu, dst, dst, src);
- } else {
- emit_instr(ctx, dmultu, dst, src);
- emit_instr(ctx, mflo, dst);
- }
- break;
- case BPF_DIV:
- case BPF_MOD:
- if (MIPS_ISA_REV >= 6) {
- if (bpf_op == BPF_DIV)
- emit_instr(ctx, ddivu_r6,
- dst, dst, src);
- else
- emit_instr(ctx, modu, dst, dst, src);
- break;
- }
- emit_instr(ctx, ddivu, dst, src);
- if (bpf_op == BPF_DIV)
- emit_instr(ctx, mflo, dst);
- else
- emit_instr(ctx, mfhi, dst);
- break;
- case BPF_LSH:
- emit_instr(ctx, dsllv, dst, dst, src);
- break;
- case BPF_RSH:
- emit_instr(ctx, dsrlv, dst, dst, src);
- break;
- case BPF_ARSH:
- emit_instr(ctx, dsrav, dst, dst, src);
- break;
- default:
- pr_err("ALU64_REG NOT HANDLED\n");
- return -EINVAL;
- }
- break;
- case BPF_ALU | BPF_MOV | BPF_X: /* ALU_REG */
- case BPF_ALU | BPF_ADD | BPF_X: /* ALU_REG */
- case BPF_ALU | BPF_SUB | BPF_X: /* ALU_REG */
- case BPF_ALU | BPF_XOR | BPF_X: /* ALU_REG */
- case BPF_ALU | BPF_OR | BPF_X: /* ALU_REG */
- case BPF_ALU | BPF_AND | BPF_X: /* ALU_REG */
- case BPF_ALU | BPF_MUL | BPF_X: /* ALU_REG */
- case BPF_ALU | BPF_DIV | BPF_X: /* ALU_REG */
- case BPF_ALU | BPF_MOD | BPF_X: /* ALU_REG */
- case BPF_ALU | BPF_LSH | BPF_X: /* ALU_REG */
- case BPF_ALU | BPF_RSH | BPF_X: /* ALU_REG */
- case BPF_ALU | BPF_ARSH | BPF_X: /* ALU_REG */
- src = ebpf_to_mips_reg(ctx, insn, src_reg_no_fp);
- dst = ebpf_to_mips_reg(ctx, insn, dst_reg);
- if (src < 0 || dst < 0)
- return -EINVAL;
- td = get_reg_val_type(ctx, this_idx, insn->dst_reg);
- if (td == REG_64BIT) {
- /* sign extend */
- emit_instr(ctx, sll, dst, dst, 0);
- }
- did_move = false;
- ts = get_reg_val_type(ctx, this_idx, insn->src_reg);
- if (ts == REG_64BIT) {
- int tmp_reg = MIPS_R_AT;
-
- if (bpf_op == BPF_MOV) {
- tmp_reg = dst;
- did_move = true;
- }
- /* sign extend */
- emit_instr(ctx, sll, tmp_reg, src, 0);
- src = MIPS_R_AT;
- }
- switch (bpf_op) {
- case BPF_MOV:
- if (!did_move)
- emit_instr(ctx, addu, dst, src, MIPS_R_ZERO);
- break;
- case BPF_ADD:
- emit_instr(ctx, addu, dst, dst, src);
- break;
- case BPF_SUB:
- emit_instr(ctx, subu, dst, dst, src);
- break;
- case BPF_XOR:
- emit_instr(ctx, xor, dst, dst, src);
- break;
- case BPF_OR:
- emit_instr(ctx, or, dst, dst, src);
- break;
- case BPF_AND:
- emit_instr(ctx, and, dst, dst, src);
- break;
- case BPF_MUL:
- emit_instr(ctx, mul, dst, dst, src);
- break;
- case BPF_DIV:
- case BPF_MOD:
- if (MIPS_ISA_REV >= 6) {
- if (bpf_op == BPF_DIV)
- emit_instr(ctx, divu_r6, dst, dst, src);
- else
- emit_instr(ctx, modu, dst, dst, src);
- break;
- }
- emit_instr(ctx, divu, dst, src);
- if (bpf_op == BPF_DIV)
- emit_instr(ctx, mflo, dst);
- else
- emit_instr(ctx, mfhi, dst);
- break;
- case BPF_LSH:
- emit_instr(ctx, sllv, dst, dst, src);
- break;
- case BPF_RSH:
- emit_instr(ctx, srlv, dst, dst, src);
- break;
- case BPF_ARSH:
- emit_instr(ctx, srav, dst, dst, src);
- break;
- default:
- pr_err("ALU_REG NOT HANDLED\n");
- return -EINVAL;
- }
- break;
- case BPF_JMP | BPF_EXIT:
- if (this_idx + 1 < exit_idx) {
- b_off = b_imm(exit_idx, ctx);
- if (is_bad_offset(b_off))
- return -E2BIG;
- emit_instr(ctx, beq, MIPS_R_ZERO, MIPS_R_ZERO, b_off);
- emit_instr(ctx, nop);
- }
- break;
- case BPF_JMP | BPF_JEQ | BPF_K: /* JMP_IMM */
- case BPF_JMP | BPF_JNE | BPF_K: /* JMP_IMM */
- cmp_eq = (bpf_op == BPF_JEQ);
- dst = ebpf_to_mips_reg(ctx, insn, dst_reg_fp_ok);
- if (dst < 0)
- return dst;
- if (insn->imm == 0) {
- src = MIPS_R_ZERO;
- } else {
- gen_imm_to_reg(insn, MIPS_R_AT, ctx);
- src = MIPS_R_AT;
- }
- goto jeq_common;
- case BPF_JMP | BPF_JEQ | BPF_X: /* JMP_REG */
- case BPF_JMP | BPF_JNE | BPF_X:
- case BPF_JMP | BPF_JSLT | BPF_X:
- case BPF_JMP | BPF_JSLE | BPF_X:
- case BPF_JMP | BPF_JSGT | BPF_X:
- case BPF_JMP | BPF_JSGE | BPF_X:
- case BPF_JMP | BPF_JLT | BPF_X:
- case BPF_JMP | BPF_JLE | BPF_X:
- case BPF_JMP | BPF_JGT | BPF_X:
- case BPF_JMP | BPF_JGE | BPF_X:
- case BPF_JMP | BPF_JSET | BPF_X:
- src = ebpf_to_mips_reg(ctx, insn, src_reg_no_fp);
- dst = ebpf_to_mips_reg(ctx, insn, dst_reg);
- if (src < 0 || dst < 0)
- return -EINVAL;
- td = get_reg_val_type(ctx, this_idx, insn->dst_reg);
- ts = get_reg_val_type(ctx, this_idx, insn->src_reg);
- if (td == REG_32BIT && ts != REG_32BIT) {
- emit_instr(ctx, sll, MIPS_R_AT, src, 0);
- src = MIPS_R_AT;
- } else if (ts == REG_32BIT && td != REG_32BIT) {
- emit_instr(ctx, sll, MIPS_R_AT, dst, 0);
- dst = MIPS_R_AT;
- }
- if (bpf_op == BPF_JSET) {
- emit_instr(ctx, and, MIPS_R_AT, dst, src);
- cmp_eq = false;
- dst = MIPS_R_AT;
- src = MIPS_R_ZERO;
- } else if (bpf_op == BPF_JSGT || bpf_op == BPF_JSLE) {
- emit_instr(ctx, dsubu, MIPS_R_AT, dst, src);
- if ((insn + 1)->code == (BPF_JMP | BPF_EXIT) && insn->off == 1) {
- b_off = b_imm(exit_idx, ctx);
- if (is_bad_offset(b_off))
- return -E2BIG;
- if (bpf_op == BPF_JSGT)
- emit_instr(ctx, blez, MIPS_R_AT, b_off);
- else
- emit_instr(ctx, bgtz, MIPS_R_AT, b_off);
- emit_instr(ctx, nop);
- return 2; /* We consumed the exit. */
- }
- b_off = b_imm(this_idx + insn->off + 1, ctx);
- if (is_bad_offset(b_off))
- return -E2BIG;
- if (bpf_op == BPF_JSGT)
- emit_instr(ctx, bgtz, MIPS_R_AT, b_off);
- else
- emit_instr(ctx, blez, MIPS_R_AT, b_off);
- emit_instr(ctx, nop);
- break;
- } else if (bpf_op == BPF_JSGE || bpf_op == BPF_JSLT) {
- emit_instr(ctx, slt, MIPS_R_AT, dst, src);
- cmp_eq = bpf_op == BPF_JSGE;
- dst = MIPS_R_AT;
- src = MIPS_R_ZERO;
- } else if (bpf_op == BPF_JGT || bpf_op == BPF_JLE) {
- /* dst or src could be AT */
- emit_instr(ctx, dsubu, MIPS_R_T8, dst, src);
- emit_instr(ctx, sltu, MIPS_R_AT, dst, src);
- /* SP known to be non-zero, movz becomes boolean not */
- if (MIPS_ISA_REV >= 6) {
- emit_instr(ctx, seleqz, MIPS_R_T9,
- MIPS_R_SP, MIPS_R_T8);
- } else {
- emit_instr(ctx, movz, MIPS_R_T9,
- MIPS_R_SP, MIPS_R_T8);
- emit_instr(ctx, movn, MIPS_R_T9,
- MIPS_R_ZERO, MIPS_R_T8);
- }
- emit_instr(ctx, or, MIPS_R_AT, MIPS_R_T9, MIPS_R_AT);
- cmp_eq = bpf_op == BPF_JGT;
- dst = MIPS_R_AT;
- src = MIPS_R_ZERO;
- } else if (bpf_op == BPF_JGE || bpf_op == BPF_JLT) {
- emit_instr(ctx, sltu, MIPS_R_AT, dst, src);
- cmp_eq = bpf_op == BPF_JGE;
- dst = MIPS_R_AT;
- src = MIPS_R_ZERO;
- } else { /* JNE/JEQ case */
- cmp_eq = (bpf_op == BPF_JEQ);
- }
-jeq_common:
- /*
- * If the next insn is EXIT and we are jumping arround
- * only it, invert the sense of the compare and
- * conditionally jump to the exit. Poor man's branch
- * chaining.
- */
- if ((insn + 1)->code == (BPF_JMP | BPF_EXIT) && insn->off == 1) {
- b_off = b_imm(exit_idx, ctx);
- if (is_bad_offset(b_off)) {
- target = j_target(ctx, exit_idx);
- if (target == (unsigned int)-1)
- return -E2BIG;
- cmp_eq = !cmp_eq;
- b_off = 4 * 3;
- if (!(ctx->offsets[this_idx] & OFFSETS_B_CONV)) {
- ctx->offsets[this_idx] |= OFFSETS_B_CONV;
- ctx->long_b_conversion = 1;
- }
- }
-
- if (cmp_eq)
- emit_instr(ctx, bne, dst, src, b_off);
- else
- emit_instr(ctx, beq, dst, src, b_off);
- emit_instr(ctx, nop);
- if (ctx->offsets[this_idx] & OFFSETS_B_CONV) {
- emit_instr(ctx, j, target);
- emit_instr(ctx, nop);
- }
- return 2; /* We consumed the exit. */
- }
- b_off = b_imm(this_idx + insn->off + 1, ctx);
- if (is_bad_offset(b_off)) {
- target = j_target(ctx, this_idx + insn->off + 1);
- if (target == (unsigned int)-1)
- return -E2BIG;
- cmp_eq = !cmp_eq;
- b_off = 4 * 3;
- if (!(ctx->offsets[this_idx] & OFFSETS_B_CONV)) {
- ctx->offsets[this_idx] |= OFFSETS_B_CONV;
- ctx->long_b_conversion = 1;
- }
- }
-
- if (cmp_eq)
- emit_instr(ctx, beq, dst, src, b_off);
- else
- emit_instr(ctx, bne, dst, src, b_off);
- emit_instr(ctx, nop);
- if (ctx->offsets[this_idx] & OFFSETS_B_CONV) {
- emit_instr(ctx, j, target);
- emit_instr(ctx, nop);
- }
- break;
- case BPF_JMP | BPF_JSGT | BPF_K: /* JMP_IMM */
- case BPF_JMP | BPF_JSGE | BPF_K: /* JMP_IMM */
- case BPF_JMP | BPF_JSLT | BPF_K: /* JMP_IMM */
- case BPF_JMP | BPF_JSLE | BPF_K: /* JMP_IMM */
- cmp_eq = (bpf_op == BPF_JSGE);
- dst = ebpf_to_mips_reg(ctx, insn, dst_reg_fp_ok);
- if (dst < 0)
- return dst;
-
- if (insn->imm == 0) {
- if ((insn + 1)->code == (BPF_JMP | BPF_EXIT) && insn->off == 1) {
- b_off = b_imm(exit_idx, ctx);
- if (is_bad_offset(b_off))
- return -E2BIG;
- switch (bpf_op) {
- case BPF_JSGT:
- emit_instr(ctx, blez, dst, b_off);
- break;
- case BPF_JSGE:
- emit_instr(ctx, bltz, dst, b_off);
- break;
- case BPF_JSLT:
- emit_instr(ctx, bgez, dst, b_off);
- break;
- case BPF_JSLE:
- emit_instr(ctx, bgtz, dst, b_off);
- break;
- }
- emit_instr(ctx, nop);
- return 2; /* We consumed the exit. */
- }
- b_off = b_imm(this_idx + insn->off + 1, ctx);
- if (is_bad_offset(b_off))
- return -E2BIG;
- switch (bpf_op) {
- case BPF_JSGT:
- emit_instr(ctx, bgtz, dst, b_off);
- break;
- case BPF_JSGE:
- emit_instr(ctx, bgez, dst, b_off);
- break;
- case BPF_JSLT:
- emit_instr(ctx, bltz, dst, b_off);
- break;
- case BPF_JSLE:
- emit_instr(ctx, blez, dst, b_off);
- break;
- }
- emit_instr(ctx, nop);
- break;
- }
- /*
- * only "LT" compare available, so we must use imm + 1
- * to generate "GT" and imm -1 to generate LE
- */
- if (bpf_op == BPF_JSGT)
- t64s = insn->imm + 1;
- else if (bpf_op == BPF_JSLE)
- t64s = insn->imm + 1;
- else
- t64s = insn->imm;
-
- cmp_eq = bpf_op == BPF_JSGT || bpf_op == BPF_JSGE;
- if (t64s >= S16_MIN && t64s <= S16_MAX) {
- emit_instr(ctx, slti, MIPS_R_AT, dst, (int)t64s);
- src = MIPS_R_AT;
- dst = MIPS_R_ZERO;
- goto jeq_common;
- }
- emit_const_to_reg(ctx, MIPS_R_AT, (u64)t64s);
- emit_instr(ctx, slt, MIPS_R_AT, dst, MIPS_R_AT);
- src = MIPS_R_AT;
- dst = MIPS_R_ZERO;
- goto jeq_common;
-
- case BPF_JMP | BPF_JGT | BPF_K:
- case BPF_JMP | BPF_JGE | BPF_K:
- case BPF_JMP | BPF_JLT | BPF_K:
- case BPF_JMP | BPF_JLE | BPF_K:
- cmp_eq = (bpf_op == BPF_JGE);
- dst = ebpf_to_mips_reg(ctx, insn, dst_reg_fp_ok);
- if (dst < 0)
- return dst;
- /*
- * only "LT" compare available, so we must use imm + 1
- * to generate "GT" and imm -1 to generate LE
- */
- if (bpf_op == BPF_JGT)
- t64s = (u64)(u32)(insn->imm) + 1;
- else if (bpf_op == BPF_JLE)
- t64s = (u64)(u32)(insn->imm) + 1;
- else
- t64s = (u64)(u32)(insn->imm);
-
- cmp_eq = bpf_op == BPF_JGT || bpf_op == BPF_JGE;
-
- emit_const_to_reg(ctx, MIPS_R_AT, (u64)t64s);
- emit_instr(ctx, sltu, MIPS_R_AT, dst, MIPS_R_AT);
- src = MIPS_R_AT;
- dst = MIPS_R_ZERO;
- goto jeq_common;
-
- case BPF_JMP | BPF_JSET | BPF_K: /* JMP_IMM */
- dst = ebpf_to_mips_reg(ctx, insn, dst_reg_fp_ok);
- if (dst < 0)
- return dst;
-
- if (ctx->use_bbit_insns && hweight32((u32)insn->imm) == 1) {
- if ((insn + 1)->code == (BPF_JMP | BPF_EXIT) && insn->off == 1) {
- b_off = b_imm(exit_idx, ctx);
- if (is_bad_offset(b_off))
- return -E2BIG;
- emit_instr(ctx, bbit0, dst, ffs((u32)insn->imm) - 1, b_off);
- emit_instr(ctx, nop);
- return 2; /* We consumed the exit. */
- }
- b_off = b_imm(this_idx + insn->off + 1, ctx);
- if (is_bad_offset(b_off))
- return -E2BIG;
- emit_instr(ctx, bbit1, dst, ffs((u32)insn->imm) - 1, b_off);
- emit_instr(ctx, nop);
- break;
- }
- t64 = (u32)insn->imm;
- emit_const_to_reg(ctx, MIPS_R_AT, t64);
- emit_instr(ctx, and, MIPS_R_AT, dst, MIPS_R_AT);
- src = MIPS_R_AT;
- dst = MIPS_R_ZERO;
- cmp_eq = false;
- goto jeq_common;
-
- case BPF_JMP | BPF_JA:
- /*
- * Prefer relative branch for easier debugging, but
- * fall back if needed.
- */
- b_off = b_imm(this_idx + insn->off + 1, ctx);
- if (is_bad_offset(b_off)) {
- target = j_target(ctx, this_idx + insn->off + 1);
- if (target == (unsigned int)-1)
- return -E2BIG;
- emit_instr(ctx, j, target);
- } else {
- emit_instr(ctx, b, b_off);
- }
- emit_instr(ctx, nop);
- break;
- case BPF_LD | BPF_DW | BPF_IMM:
- if (insn->src_reg != 0)
- return -EINVAL;
- dst = ebpf_to_mips_reg(ctx, insn, dst_reg);
- if (dst < 0)
- return dst;
- t64 = ((u64)(u32)insn->imm) | ((u64)(insn + 1)->imm << 32);
- emit_const_to_reg(ctx, dst, t64);
- return 2; /* Double slot insn */
-
- case BPF_JMP | BPF_CALL:
- ctx->flags |= EBPF_SAVE_RA;
- t64s = (s64)insn->imm + (long)__bpf_call_base;
- emit_const_to_reg(ctx, MIPS_R_T9, (u64)t64s);
- emit_instr(ctx, jalr, MIPS_R_RA, MIPS_R_T9);
- /* delay slot */
- emit_instr(ctx, nop);
- break;
-
- case BPF_JMP | BPF_TAIL_CALL:
- if (emit_bpf_tail_call(ctx, this_idx))
- return -EINVAL;
- break;
-
- case BPF_ALU | BPF_END | BPF_FROM_BE:
- case BPF_ALU | BPF_END | BPF_FROM_LE:
- dst = ebpf_to_mips_reg(ctx, insn, dst_reg);
- if (dst < 0)
- return dst;
- td = get_reg_val_type(ctx, this_idx, insn->dst_reg);
- if (insn->imm == 64 && td == REG_32BIT)
- emit_instr(ctx, dinsu, dst, MIPS_R_ZERO, 32, 32);
-
- if (insn->imm != 64 && td == REG_64BIT) {
- /* sign extend */
- emit_instr(ctx, sll, dst, dst, 0);
- }
-
-#ifdef __BIG_ENDIAN
- need_swap = (BPF_SRC(insn->code) == BPF_FROM_LE);
-#else
- need_swap = (BPF_SRC(insn->code) == BPF_FROM_BE);
-#endif
- if (insn->imm == 16) {
- if (need_swap)
- emit_instr(ctx, wsbh, dst, dst);
- emit_instr(ctx, andi, dst, dst, 0xffff);
- } else if (insn->imm == 32) {
- if (need_swap) {
- emit_instr(ctx, wsbh, dst, dst);
- emit_instr(ctx, rotr, dst, dst, 16);
- }
- } else { /* 64-bit*/
- if (need_swap) {
- emit_instr(ctx, dsbh, dst, dst);
- emit_instr(ctx, dshd, dst, dst);
- }
- }
- break;
-
- case BPF_ST | BPF_B | BPF_MEM:
- case BPF_ST | BPF_H | BPF_MEM:
- case BPF_ST | BPF_W | BPF_MEM:
- case BPF_ST | BPF_DW | BPF_MEM:
- if (insn->dst_reg == BPF_REG_10) {
- ctx->flags |= EBPF_SEEN_FP;
- dst = MIPS_R_SP;
- mem_off = insn->off + MAX_BPF_STACK;
- } else {
- dst = ebpf_to_mips_reg(ctx, insn, dst_reg);
- if (dst < 0)
- return dst;
- mem_off = insn->off;
- }
- gen_imm_to_reg(insn, MIPS_R_AT, ctx);
- switch (BPF_SIZE(insn->code)) {
- case BPF_B:
- emit_instr(ctx, sb, MIPS_R_AT, mem_off, dst);
- break;
- case BPF_H:
- emit_instr(ctx, sh, MIPS_R_AT, mem_off, dst);
- break;
- case BPF_W:
- emit_instr(ctx, sw, MIPS_R_AT, mem_off, dst);
- break;
- case BPF_DW:
- emit_instr(ctx, sd, MIPS_R_AT, mem_off, dst);
- break;
- }
- break;
-
- case BPF_LDX | BPF_B | BPF_MEM:
- case BPF_LDX | BPF_H | BPF_MEM:
- case BPF_LDX | BPF_W | BPF_MEM:
- case BPF_LDX | BPF_DW | BPF_MEM:
- if (insn->src_reg == BPF_REG_10) {
- ctx->flags |= EBPF_SEEN_FP;
- src = MIPS_R_SP;
- mem_off = insn->off + MAX_BPF_STACK;
- } else {
- src = ebpf_to_mips_reg(ctx, insn, src_reg_no_fp);
- if (src < 0)
- return src;
- mem_off = insn->off;
- }
- dst = ebpf_to_mips_reg(ctx, insn, dst_reg);
- if (dst < 0)
- return dst;
- switch (BPF_SIZE(insn->code)) {
- case BPF_B:
- emit_instr(ctx, lbu, dst, mem_off, src);
- break;
- case BPF_H:
- emit_instr(ctx, lhu, dst, mem_off, src);
- break;
- case BPF_W:
- emit_instr(ctx, lw, dst, mem_off, src);
- break;
- case BPF_DW:
- emit_instr(ctx, ld, dst, mem_off, src);
- break;
- }
- break;
-
- case BPF_STX | BPF_B | BPF_MEM:
- case BPF_STX | BPF_H | BPF_MEM:
- case BPF_STX | BPF_W | BPF_MEM:
- case BPF_STX | BPF_DW | BPF_MEM:
- case BPF_STX | BPF_W | BPF_XADD:
- case BPF_STX | BPF_DW | BPF_XADD:
- if (insn->dst_reg == BPF_REG_10) {
- ctx->flags |= EBPF_SEEN_FP;
- dst = MIPS_R_SP;
- mem_off = insn->off + MAX_BPF_STACK;
- } else {
- dst = ebpf_to_mips_reg(ctx, insn, dst_reg);
- if (dst < 0)
- return dst;
- mem_off = insn->off;
- }
- src = ebpf_to_mips_reg(ctx, insn, src_reg_no_fp);
- if (src < 0)
- return src;
- if (BPF_MODE(insn->code) == BPF_XADD) {
- /*
- * If mem_off does not fit within the 9 bit ll/sc
- * instruction immediate field, use a temp reg.
- */
- if (MIPS_ISA_REV >= 6 &&
- (mem_off >= BIT(8) || mem_off < -BIT(8))) {
- emit_instr(ctx, daddiu, MIPS_R_T6,
- dst, mem_off);
- mem_off = 0;
- dst = MIPS_R_T6;
- }
- switch (BPF_SIZE(insn->code)) {
- case BPF_W:
- if (get_reg_val_type(ctx, this_idx, insn->src_reg) == REG_32BIT) {
- emit_instr(ctx, sll, MIPS_R_AT, src, 0);
- src = MIPS_R_AT;
- }
- emit_instr(ctx, ll, MIPS_R_T8, mem_off, dst);
- emit_instr(ctx, addu, MIPS_R_T8, MIPS_R_T8, src);
- emit_instr(ctx, sc, MIPS_R_T8, mem_off, dst);
- /*
- * On failure back up to LL (-4
- * instructions of 4 bytes each
- */
- emit_instr(ctx, beq, MIPS_R_T8, MIPS_R_ZERO, -4 * 4);
- emit_instr(ctx, nop);
- break;
- case BPF_DW:
- if (get_reg_val_type(ctx, this_idx, insn->src_reg) == REG_32BIT) {
- emit_instr(ctx, daddu, MIPS_R_AT, src, MIPS_R_ZERO);
- emit_instr(ctx, dinsu, MIPS_R_AT, MIPS_R_ZERO, 32, 32);
- src = MIPS_R_AT;
- }
- emit_instr(ctx, lld, MIPS_R_T8, mem_off, dst);
- emit_instr(ctx, daddu, MIPS_R_T8, MIPS_R_T8, src);
- emit_instr(ctx, scd, MIPS_R_T8, mem_off, dst);
- emit_instr(ctx, beq, MIPS_R_T8, MIPS_R_ZERO, -4 * 4);
- emit_instr(ctx, nop);
- break;
- }
- } else { /* BPF_MEM */
- switch (BPF_SIZE(insn->code)) {
- case BPF_B:
- emit_instr(ctx, sb, src, mem_off, dst);
- break;
- case BPF_H:
- emit_instr(ctx, sh, src, mem_off, dst);
- break;
- case BPF_W:
- emit_instr(ctx, sw, src, mem_off, dst);
- break;
- case BPF_DW:
- if (get_reg_val_type(ctx, this_idx, insn->src_reg) == REG_32BIT) {
- emit_instr(ctx, daddu, MIPS_R_AT, src, MIPS_R_ZERO);
- emit_instr(ctx, dinsu, MIPS_R_AT, MIPS_R_ZERO, 32, 32);
- src = MIPS_R_AT;
- }
- emit_instr(ctx, sd, src, mem_off, dst);
- break;
- }
- }
- break;
-
- default:
- pr_err("NOT HANDLED %d - (%02x)\n",
- this_idx, (unsigned int)insn->code);
- return -EINVAL;
- }
- return 1;
-}
-
-#define RVT_VISITED_MASK 0xc000000000000000ull
-#define RVT_FALL_THROUGH 0x4000000000000000ull
-#define RVT_BRANCH_TAKEN 0x8000000000000000ull
-#define RVT_DONE (RVT_FALL_THROUGH | RVT_BRANCH_TAKEN)
-
-static int build_int_body(struct jit_ctx *ctx)
-{
- const struct bpf_prog *prog = ctx->skf;
- const struct bpf_insn *insn;
- int i, r;
-
- for (i = 0; i < prog->len; ) {
- insn = prog->insnsi + i;
- if ((ctx->reg_val_types[i] & RVT_VISITED_MASK) == 0) {
- /* dead instruction, don't emit it. */
- i++;
- continue;
- }
-
- if (ctx->target == NULL)
- ctx->offsets[i] = (ctx->offsets[i] & OFFSETS_B_CONV) | (ctx->idx * 4);
-
- r = build_one_insn(insn, ctx, i, prog->len);
- if (r < 0)
- return r;
- i += r;
- }
- /* epilogue offset */
- if (ctx->target == NULL)
- ctx->offsets[i] = ctx->idx * 4;
-
- /*
- * All exits have an offset of the epilogue, some offsets may
- * not have been set due to banch-around threading, so set
- * them now.
- */
- if (ctx->target == NULL)
- for (i = 0; i < prog->len; i++) {
- insn = prog->insnsi + i;
- if (insn->code == (BPF_JMP | BPF_EXIT))
- ctx->offsets[i] = ctx->idx * 4;
- }
- return 0;
-}
-
-/* return the last idx processed, or negative for error */
-static int reg_val_propagate_range(struct jit_ctx *ctx, u64 initial_rvt,
- int start_idx, bool follow_taken)
-{
- const struct bpf_prog *prog = ctx->skf;
- const struct bpf_insn *insn;
- u64 exit_rvt = initial_rvt;
- u64 *rvt = ctx->reg_val_types;
- int idx;
- int reg;
-
- for (idx = start_idx; idx < prog->len; idx++) {
- rvt[idx] = (rvt[idx] & RVT_VISITED_MASK) | exit_rvt;
- insn = prog->insnsi + idx;
- switch (BPF_CLASS(insn->code)) {
- case BPF_ALU:
- switch (BPF_OP(insn->code)) {
- case BPF_ADD:
- case BPF_SUB:
- case BPF_MUL:
- case BPF_DIV:
- case BPF_OR:
- case BPF_AND:
- case BPF_LSH:
- case BPF_RSH:
- case BPF_NEG:
- case BPF_MOD:
- case BPF_XOR:
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_32BIT);
- break;
- case BPF_MOV:
- if (BPF_SRC(insn->code)) {
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_32BIT);
- } else {
- /* IMM to REG move*/
- if (insn->imm >= 0)
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_32BIT_POS);
- else
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_32BIT);
- }
- break;
- case BPF_END:
- if (insn->imm == 64)
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_64BIT);
- else if (insn->imm == 32)
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_32BIT);
- else /* insn->imm == 16 */
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_32BIT_POS);
- break;
- }
- rvt[idx] |= RVT_DONE;
- break;
- case BPF_ALU64:
- switch (BPF_OP(insn->code)) {
- case BPF_MOV:
- if (BPF_SRC(insn->code)) {
- /* REG to REG move*/
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_64BIT);
- } else {
- /* IMM to REG move*/
- if (insn->imm >= 0)
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_32BIT_POS);
- else
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_64BIT_32BIT);
- }
- break;
- default:
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_64BIT);
- }
- rvt[idx] |= RVT_DONE;
- break;
- case BPF_LD:
- switch (BPF_SIZE(insn->code)) {
- case BPF_DW:
- if (BPF_MODE(insn->code) == BPF_IMM) {
- s64 val;
-
- val = (s64)((u32)insn->imm | ((u64)(insn + 1)->imm << 32));
- if (val > 0 && val <= S32_MAX)
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_32BIT_POS);
- else if (val >= S32_MIN && val <= S32_MAX)
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_64BIT_32BIT);
- else
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_64BIT);
- rvt[idx] |= RVT_DONE;
- idx++;
- } else {
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_64BIT);
- }
- break;
- case BPF_B:
- case BPF_H:
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_32BIT_POS);
- break;
- case BPF_W:
- if (BPF_MODE(insn->code) == BPF_IMM)
- set_reg_val_type(&exit_rvt, insn->dst_reg,
- insn->imm >= 0 ? REG_32BIT_POS : REG_32BIT);
- else
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_32BIT);
- break;
- }
- rvt[idx] |= RVT_DONE;
- break;
- case BPF_LDX:
- switch (BPF_SIZE(insn->code)) {
- case BPF_DW:
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_64BIT);
- break;
- case BPF_B:
- case BPF_H:
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_32BIT_POS);
- break;
- case BPF_W:
- set_reg_val_type(&exit_rvt, insn->dst_reg, REG_32BIT);
- break;
- }
- rvt[idx] |= RVT_DONE;
- break;
- case BPF_JMP:
- switch (BPF_OP(insn->code)) {
- case BPF_EXIT:
- rvt[idx] = RVT_DONE | exit_rvt;
- rvt[prog->len] = exit_rvt;
- return idx;
- case BPF_JA:
- rvt[idx] |= RVT_DONE;
- idx += insn->off;
- break;
- case BPF_JEQ:
- case BPF_JGT:
- case BPF_JGE:
- case BPF_JLT:
- case BPF_JLE:
- case BPF_JSET:
- case BPF_JNE:
- case BPF_JSGT:
- case BPF_JSGE:
- case BPF_JSLT:
- case BPF_JSLE:
- if (follow_taken) {
- rvt[idx] |= RVT_BRANCH_TAKEN;
- idx += insn->off;
- follow_taken = false;
- } else {
- rvt[idx] |= RVT_FALL_THROUGH;
- }
- break;
- case BPF_CALL:
- set_reg_val_type(&exit_rvt, BPF_REG_0, REG_64BIT);
- /* Upon call return, argument registers are clobbered. */
- for (reg = BPF_REG_0; reg <= BPF_REG_5; reg++)
- set_reg_val_type(&exit_rvt, reg, REG_64BIT);
-
- rvt[idx] |= RVT_DONE;
- break;
- default:
- WARN(1, "Unhandled BPF_JMP case.\n");
- rvt[idx] |= RVT_DONE;
- break;
- }
- break;
- default:
- rvt[idx] |= RVT_DONE;
- break;
- }
- }
- return idx;
-}
-
-/*
- * Track the value range (i.e. 32-bit vs. 64-bit) of each register at
- * each eBPF insn. This allows unneeded sign and zero extension
- * operations to be omitted.
- *
- * Doesn't handle yet confluence of control paths with conflicting
- * ranges, but it is good enough for most sane code.
- */
-static int reg_val_propagate(struct jit_ctx *ctx)
-{
- const struct bpf_prog *prog = ctx->skf;
- u64 exit_rvt;
- int reg;
- int i;
-
- /*
- * 11 registers * 3 bits/reg leaves top bits free for other
- * uses. Bit-62..63 used to see if we have visited an insn.
- */
- exit_rvt = 0;
-
- /* Upon entry, argument registers are 64-bit. */
- for (reg = BPF_REG_1; reg <= BPF_REG_5; reg++)
- set_reg_val_type(&exit_rvt, reg, REG_64BIT);
-
- /*
- * First follow all conditional branches on the fall-through
- * edge of control flow..
- */
- reg_val_propagate_range(ctx, exit_rvt, 0, false);
-restart_search:
- /*
- * Then repeatedly find the first conditional branch where
- * both edges of control flow have not been taken, and follow
- * the branch taken edge. We will end up restarting the
- * search once per conditional branch insn.
- */
- for (i = 0; i < prog->len; i++) {
- u64 rvt = ctx->reg_val_types[i];
-
- if ((rvt & RVT_VISITED_MASK) == RVT_DONE ||
- (rvt & RVT_VISITED_MASK) == 0)
- continue;
- if ((rvt & RVT_VISITED_MASK) == RVT_FALL_THROUGH) {
- reg_val_propagate_range(ctx, rvt & ~RVT_VISITED_MASK, i, true);
- } else { /* RVT_BRANCH_TAKEN */
- WARN(1, "Unexpected RVT_BRANCH_TAKEN case.\n");
- reg_val_propagate_range(ctx, rvt & ~RVT_VISITED_MASK, i, false);
- }
- goto restart_search;
- }
- /*
- * Eventually all conditional branches have been followed on
- * both branches and we are done. Any insn that has not been
- * visited at this point is dead.
- */
-
- return 0;
-}
-
-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 */
-}
-
-struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
-{
- struct bpf_prog *orig_prog = prog;
- bool tmp_blinded = false;
- struct bpf_prog *tmp;
- struct bpf_binary_header *header = NULL;
- struct jit_ctx ctx;
- unsigned int image_size;
- u8 *image_ptr;
-
- if (!prog->jit_requested || MIPS_ISA_REV < 2)
- return prog;
-
- tmp = bpf_jit_blind_constants(prog);
- /* If blinding was requested and we failed during blinding,
- * we must fall back to the interpreter.
- */
- if (IS_ERR(tmp))
- return orig_prog;
- if (tmp != prog) {
- tmp_blinded = true;
- prog = tmp;
- }
-
- memset(&ctx, 0, sizeof(ctx));
-
- preempt_disable();
- switch (current_cpu_type()) {
- case CPU_CAVIUM_OCTEON:
- case CPU_CAVIUM_OCTEON_PLUS:
- case CPU_CAVIUM_OCTEON2:
- case CPU_CAVIUM_OCTEON3:
- ctx.use_bbit_insns = 1;
- break;
- default:
- ctx.use_bbit_insns = 0;
- }
- preempt_enable();
-
- ctx.offsets = kcalloc(prog->len + 1, sizeof(*ctx.offsets), GFP_KERNEL);
- if (ctx.offsets == NULL)
- goto out_err;
-
- ctx.reg_val_types = kcalloc(prog->len + 1, sizeof(*ctx.reg_val_types), GFP_KERNEL);
- if (ctx.reg_val_types == NULL)
- goto out_err;
-
- ctx.skf = prog;
-
- if (reg_val_propagate(&ctx))
- goto out_err;
-
- /*
- * First pass discovers used resources and instruction offsets
- * assuming short branches are used.
- */
- if (build_int_body(&ctx))
- goto out_err;
-
- /*
- * If no calls are made (EBPF_SAVE_RA), then tail call count
- * in $v1, else we must save in n$s4.
- */
- if (ctx.flags & EBPF_SEEN_TC) {
- if (ctx.flags & EBPF_SAVE_RA)
- ctx.flags |= EBPF_SAVE_S4;
- else
- ctx.flags |= EBPF_TCC_IN_V1;
- }
-
- /*
- * Second pass generates offsets, if any branches are out of
- * range a jump-around long sequence 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.
- */
- do {
- ctx.idx = 0;
- ctx.gen_b_offsets = 1;
- ctx.long_b_conversion = 0;
- if (gen_int_prologue(&ctx))
- goto out_err;
- if (build_int_body(&ctx))
- goto out_err;
- if (build_int_epilogue(&ctx, MIPS_R_RA))
- goto out_err;
- } while (ctx.long_b_conversion);
-
- image_size = 4 * ctx.idx;
-
- header = bpf_jit_binary_alloc(image_size, &image_ptr,
- sizeof(u32), jit_fill_hole);
- if (header == NULL)
- goto out_err;
-
- ctx.target = (u32 *)image_ptr;
-
- /* Third pass generates the code */
- ctx.idx = 0;
- if (gen_int_prologue(&ctx))
- goto out_err;
- if (build_int_body(&ctx))
- goto out_err;
- if (build_int_epilogue(&ctx, MIPS_R_RA))
- goto out_err;
-
- /* Update the icache */
- flush_icache_range((unsigned long)ctx.target,
- (unsigned long)&ctx.target[ctx.idx]);
-
- if (bpf_jit_enable > 1)
- /* Dump JIT code */
- bpf_jit_dump(prog->len, image_size, 2, ctx.target);
-
- bpf_jit_binary_lock_ro(header);
- prog->bpf_func = (void *)ctx.target;
- prog->jited = 1;
- prog->jited_len = image_size;
-out_normal:
- if (tmp_blinded)
- bpf_jit_prog_release_other(prog, prog == orig_prog ?
- tmp : orig_prog);
- kfree(ctx.offsets);
- kfree(ctx.reg_val_types);
-
- return prog;
-
-out_err:
- prog = orig_prog;
- if (header)
- bpf_jit_binary_free(header);
- goto out_normal;
-}