From ebcbacfa50ecd7a828f40fefbb58d641f265da0d Mon Sep 17 00:00:00 2001 From: Johan Almbladh Date: Tue, 5 Oct 2021 18:54:08 +0200 Subject: 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 Signed-off-by: Daniel Borkmann Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20211005165408.2305108-8-johan.almbladh@anyfinetworks.com --- arch/mips/net/bpf_jit.c | 1299 ----------------------------- arch/mips/net/bpf_jit.h | 81 -- arch/mips/net/bpf_jit_asm.S | 285 ------- arch/mips/net/ebpf_jit.c | 1938 ------------------------------------------- 4 files changed, 3603 deletions(-) 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 diff --git a/arch/mips/net/bpf_jit.c b/arch/mips/net/bpf_jit.c deleted file mode 100644 index cb6d22439f71..000000000000 --- a/arch/mips/net/bpf_jit.c +++ /dev/null @@ -1,1299 +0,0 @@ -/* - * Just-In-Time compiler for BPF filters on MIPS - * - * Copyright (c) 2014 Imagination Technologies Ltd. - * Author: Markos Chandras - * - * 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 -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include "bpf_jit.h" - -/* ABI - * r_skb_hl SKB header length - * r_data SKB data pointer - * r_off Offset - * r_A BPF register A - * r_X BPF register X - * r_skb *skb - * r_M *scratch memory - * r_skb_len SKB length - * - * On entry (*bpf_func)(*skb, *filter) - * a0 = MIPS_R_A0 = skb; - * a1 = MIPS_R_A1 = filter; - * - * Stack - * ... - * M[15] - * M[14] - * M[13] - * ... - * M[0] <-- r_M - * saved reg k-1 - * saved reg k-2 - * ... - * saved reg 0 <-- r_sp - * - * - * Packet layout - * - * <--------------------- len ------------------------> - * <--skb-len(r_skb_hl)-->< ----- skb->data_len ------> - * ---------------------------------------------------- - * | skb->data | - * ---------------------------------------------------- - */ - -#define ptr typeof(unsigned long) - -#define SCRATCH_OFF(k) (4 * (k)) - -/* JIT flags */ -#define SEEN_CALL (1 << BPF_MEMWORDS) -#define SEEN_SREG_SFT (BPF_MEMWORDS + 1) -#define SEEN_SREG_BASE (1 << SEEN_SREG_SFT) -#define SEEN_SREG(x) (SEEN_SREG_BASE << (x)) -#define SEEN_OFF SEEN_SREG(2) -#define SEEN_A SEEN_SREG(3) -#define SEEN_X SEEN_SREG(4) -#define SEEN_SKB SEEN_SREG(5) -#define SEEN_MEM SEEN_SREG(6) -/* SEEN_SK_DATA also implies skb_hl an skb_len */ -#define SEEN_SKB_DATA (SEEN_SREG(7) | SEEN_SREG(1) | SEEN_SREG(0)) - -/* Arguments used by JIT */ -#define ARGS_USED_BY_JIT 2 /* only applicable to 64-bit */ - -#define SBIT(x) (1 << (x)) /* Signed version of BIT() */ - -/** - * struct jit_ctx - JIT context - * @skf: The sk_filter - * @prologue_bytes: Number of bytes for prologue - * @idx: Instruction index - * @flags: JIT flags - * @offsets: Instruction offsets - * @target: Memory location for the compiled filter - */ -struct jit_ctx { - const struct bpf_prog *skf; - unsigned int prologue_bytes; - u32 idx; - u32 flags; - u32 *offsets; - u32 *target; -}; - - -static inline int optimize_div(u32 *k) -{ - /* power of 2 divides can be implemented with right shift */ - if (!(*k & (*k-1))) { - *k = ilog2(*k); - return 1; - } - - return 0; -} - -static inline void emit_jit_reg_move(ptr dst, ptr src, struct jit_ctx *ctx); - -/* Simply emit the instruction if the JIT memory space has been allocated */ -#define emit_instr(ctx, func, ...) \ -do { \ - if ((ctx)->target != NULL) { \ - u32 *p = &(ctx)->target[ctx->idx]; \ - uasm_i_##func(&p, ##__VA_ARGS__); \ - } \ - (ctx)->idx++; \ -} while (0) - -/* - * Similar to emit_instr but it must be used when we need to emit - * 32-bit or 64-bit instructions - */ -#define emit_long_instr(ctx, func, ...) \ -do { \ - if ((ctx)->target != NULL) { \ - u32 *p = &(ctx)->target[ctx->idx]; \ - UASM_i_##func(&p, ##__VA_ARGS__); \ - } \ - (ctx)->idx++; \ -} while (0) - -/* Determine if immediate is within the 16-bit signed range */ -static inline bool is_range16(s32 imm) -{ - return !(imm >= SBIT(15) || imm < -SBIT(15)); -} - -static inline void emit_addu(unsigned int dst, unsigned int src1, - unsigned int src2, struct jit_ctx *ctx) -{ - emit_instr(ctx, addu, dst, src1, src2); -} - -static inline void emit_nop(struct jit_ctx *ctx) -{ - emit_instr(ctx, nop); -} - -/* Load a u32 immediate to a register */ -static inline void emit_load_imm(unsigned int dst, u32 imm, struct jit_ctx *ctx) -{ - if (ctx->target != NULL) { - /* addiu can only handle s16 */ - if (!is_range16(imm)) { - u32 *p = &ctx->target[ctx->idx]; - uasm_i_lui(&p, r_tmp_imm, (s32)imm >> 16); - p = &ctx->target[ctx->idx + 1]; - uasm_i_ori(&p, dst, r_tmp_imm, imm & 0xffff); - } else { - u32 *p = &ctx->target[ctx->idx]; - uasm_i_addiu(&p, dst, r_zero, imm); - } - } - ctx->idx++; - - if (!is_range16(imm)) - ctx->idx++; -} - -static inline void emit_or(unsigned int dst, unsigned int src1, - unsigned int src2, struct jit_ctx *ctx) -{ - emit_instr(ctx, or, dst, src1, src2); -} - -static inline void emit_ori(unsigned int dst, unsigned src, u32 imm, - struct jit_ctx *ctx) -{ - if (imm >= BIT(16)) { - emit_load_imm(r_tmp, imm, ctx); - emit_or(dst, src, r_tmp, ctx); - } else { - emit_instr(ctx, ori, dst, src, imm); - } -} - -static inline void emit_daddiu(unsigned int dst, unsigned int src, - int imm, struct jit_ctx *ctx) -{ - /* - * Only used for stack, so the imm is relatively small - * and it fits in 15-bits - */ - emit_instr(ctx, daddiu, dst, src, imm); -} - -static inline void emit_addiu(unsigned int dst, unsigned int src, - u32 imm, struct jit_ctx *ctx) -{ - if (!is_range16(imm)) { - emit_load_imm(r_tmp, imm, ctx); - emit_addu(dst, r_tmp, src, ctx); - } else { - emit_instr(ctx, addiu, dst, src, imm); - } -} - -static inline void emit_and(unsigned int dst, unsigned int src1, - unsigned int src2, struct jit_ctx *ctx) -{ - emit_instr(ctx, and, dst, src1, src2); -} - -static inline void emit_andi(unsigned int dst, unsigned int src, - u32 imm, struct jit_ctx *ctx) -{ - /* If imm does not fit in u16 then load it to register */ - if (imm >= BIT(16)) { - emit_load_imm(r_tmp, imm, ctx); - emit_and(dst, src, r_tmp, ctx); - } else { - emit_instr(ctx, andi, dst, src, imm); - } -} - -static inline void emit_xor(unsigned int dst, unsigned int src1, - unsigned int src2, struct jit_ctx *ctx) -{ - emit_instr(ctx, xor, dst, src1, src2); -} - -static inline void emit_xori(ptr dst, ptr src, u32 imm, struct jit_ctx *ctx) -{ - /* If imm does not fit in u16 then load it to register */ - if (imm >= BIT(16)) { - emit_load_imm(r_tmp, imm, ctx); - emit_xor(dst, src, r_tmp, ctx); - } else { - emit_instr(ctx, xori, dst, src, imm); - } -} - -static inline void emit_stack_offset(int offset, struct jit_ctx *ctx) -{ - emit_long_instr(ctx, ADDIU, r_sp, r_sp, offset); -} - -static inline void emit_subu(unsigned int dst, unsigned int src1, - unsigned int src2, struct jit_ctx *ctx) -{ - emit_instr(ctx, subu, dst, src1, src2); -} - -static inline void emit_neg(unsigned int reg, struct jit_ctx *ctx) -{ - emit_subu(reg, r_zero, reg, ctx); -} - -static inline void emit_sllv(unsigned int dst, unsigned int src, - unsigned int sa, struct jit_ctx *ctx) -{ - emit_instr(ctx, sllv, dst, src, sa); -} - -static inline void emit_sll(unsigned int dst, unsigned int src, - unsigned int sa, struct jit_ctx *ctx) -{ - /* sa is 5-bits long */ - if (sa >= BIT(5)) - /* Shifting >= 32 results in zero */ - emit_jit_reg_move(dst, r_zero, ctx); - else - emit_instr(ctx, sll, dst, src, sa); -} - -static inline void emit_srlv(unsigned int dst, unsigned int src, - unsigned int sa, struct jit_ctx *ctx) -{ - emit_instr(ctx, srlv, dst, src, sa); -} - -static inline void emit_srl(unsigned int dst, unsigned int src, - unsigned int sa, struct jit_ctx *ctx) -{ - /* sa is 5-bits long */ - if (sa >= BIT(5)) - /* Shifting >= 32 results in zero */ - emit_jit_reg_move(dst, r_zero, ctx); - else - emit_instr(ctx, srl, dst, src, sa); -} - -static inline void emit_slt(unsigned int dst, unsigned int src1, - unsigned int src2, struct jit_ctx *ctx) -{ - emit_instr(ctx, slt, dst, src1, src2); -} - -static inline void emit_sltu(unsigned int dst, unsigned int src1, - unsigned int src2, struct jit_ctx *ctx) -{ - emit_instr(ctx, sltu, dst, src1, src2); -} - -static inline void emit_sltiu(unsigned dst, unsigned int src, - unsigned int imm, struct jit_ctx *ctx) -{ - /* 16 bit immediate */ - if (!is_range16((s32)imm)) { - emit_load_imm(r_tmp, imm, ctx); - emit_sltu(dst, src, r_tmp, ctx); - } else { - emit_instr(ctx, sltiu, dst, src, imm); - } - -} - -/* Store register on the stack */ -static inline void emit_store_stack_reg(ptr reg, ptr base, - unsigned int offset, - struct jit_ctx *ctx) -{ - emit_long_instr(ctx, SW, reg, offset, base); -} - -static inline void emit_store(ptr reg, ptr base, unsigned int offset, - struct jit_ctx *ctx) -{ - emit_instr(ctx, sw, reg, offset, base); -} - -static inline void emit_load_stack_reg(ptr reg, ptr base, - unsigned int offset, - struct jit_ctx *ctx) -{ - emit_long_instr(ctx, LW, reg, offset, base); -} - -static inline void emit_load(unsigned int reg, unsigned int base, - unsigned int offset, struct jit_ctx *ctx) -{ - emit_instr(ctx, lw, reg, offset, base); -} - -static inline void emit_load_byte(unsigned int reg, unsigned int base, - unsigned int offset, struct jit_ctx *ctx) -{ - emit_instr(ctx, lb, reg, offset, base); -} - -static inline void emit_half_load(unsigned int reg, unsigned int base, - unsigned int offset, struct jit_ctx *ctx) -{ - emit_instr(ctx, lh, reg, offset, base); -} - -static inline void emit_half_load_unsigned(unsigned int reg, unsigned int base, - unsigned int offset, struct jit_ctx *ctx) -{ - emit_instr(ctx, lhu, reg, offset, base); -} - -static inline void emit_mul(unsigned int dst, unsigned int src1, - unsigned int src2, struct jit_ctx *ctx) -{ - emit_instr(ctx, mul, dst, src1, src2); -} - -static inline void emit_div(unsigned int dst, unsigned int src, - struct jit_ctx *ctx) -{ - if (ctx->target != NULL) { - u32 *p = &ctx->target[ctx->idx]; - uasm_i_divu(&p, dst, src); - p = &ctx->target[ctx->idx + 1]; - uasm_i_mflo(&p, dst); - } - ctx->idx += 2; /* 2 insts */ -} - -static inline void emit_mod(unsigned int dst, unsigned int src, - struct jit_ctx *ctx) -{ - if (ctx->target != NULL) { - u32 *p = &ctx->target[ctx->idx]; - uasm_i_divu(&p, dst, src); - p = &ctx->target[ctx->idx + 1]; - uasm_i_mfhi(&p, dst); - } - ctx->idx += 2; /* 2 insts */ -} - -static inline void emit_dsll(unsigned int dst, unsigned int src, - unsigned int sa, struct jit_ctx *ctx) -{ - emit_instr(ctx, dsll, dst, src, sa); -} - -static inline void emit_dsrl32(unsigned int dst, unsigned int src, - unsigned int sa, struct jit_ctx *ctx) -{ - emit_instr(ctx, dsrl32, dst, src, sa); -} - -static inline void emit_wsbh(unsigned int dst, unsigned int src, - struct jit_ctx *ctx) -{ - emit_instr(ctx, wsbh, dst, src); -} - -/* load pointer to register */ -static inline void emit_load_ptr(unsigned int dst, unsigned int src, - int imm, struct jit_ctx *ctx) -{ - /* src contains the base addr of the 32/64-pointer */ - emit_long_instr(ctx, LW, dst, imm, src); -} - -/* load a function pointer to register */ -static inline void emit_load_func(unsigned int reg, ptr imm, - struct jit_ctx *ctx) -{ - if (IS_ENABLED(CONFIG_64BIT)) { - /* At this point imm is always 64-bit */ - emit_load_imm(r_tmp, (u64)imm >> 32, ctx); - emit_dsll(r_tmp_imm, r_tmp, 16, ctx); /* left shift by 16 */ - emit_ori(r_tmp, r_tmp_imm, (imm >> 16) & 0xffff, ctx); - emit_dsll(r_tmp_imm, r_tmp, 16, ctx); /* left shift by 16 */ - emit_ori(reg, r_tmp_imm, imm & 0xffff, ctx); - } else { - emit_load_imm(reg, imm, ctx); - } -} - -/* Move to real MIPS register */ -static inline void emit_reg_move(ptr dst, ptr src, struct jit_ctx *ctx) -{ - emit_long_instr(ctx, ADDU, dst, src, r_zero); -} - -/* Move to JIT (32-bit) register */ -static inline void emit_jit_reg_move(ptr dst, ptr src, struct jit_ctx *ctx) -{ - emit_addu(dst, src, r_zero, ctx); -} - -/* Compute the immediate value for PC-relative branches. */ -static inline u32 b_imm(unsigned int tgt, struct jit_ctx *ctx) -{ - if (ctx->target == NULL) - return 0; - - /* - * We want a pc-relative branch. We only do forward branches - * so tgt is always after pc. 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] - - (ctx->idx * 4 - ctx->prologue_bytes) - 4; -} - -static inline void emit_bcond(int cond, unsigned int reg1, unsigned int reg2, - unsigned int imm, struct jit_ctx *ctx) -{ - if (ctx->target != NULL) { - u32 *p = &ctx->target[ctx->idx]; - - switch (cond) { - case MIPS_COND_EQ: - uasm_i_beq(&p, reg1, reg2, imm); - break; - case MIPS_COND_NE: - uasm_i_bne(&p, reg1, reg2, imm); - break; - case MIPS_COND_ALL: - uasm_i_b(&p, imm); - break; - default: - pr_warn("%s: Unhandled branch conditional: %d\n", - __func__, cond); - } - } - ctx->idx++; -} - -static inline void emit_b(unsigned int imm, struct jit_ctx *ctx) -{ - emit_bcond(MIPS_COND_ALL, r_zero, r_zero, imm, ctx); -} - -static inline void emit_jalr(unsigned int link, unsigned int reg, - struct jit_ctx *ctx) -{ - emit_instr(ctx, jalr, link, reg); -} - -static inline void emit_jr(unsigned int reg, struct jit_ctx *ctx) -{ - emit_instr(ctx, jr, reg); -} - -static inline u16 align_sp(unsigned int num) -{ - /* Double word alignment for 32-bit, quadword for 64-bit */ - unsigned int align = IS_ENABLED(CONFIG_64BIT) ? 16 : 8; - num = (num + (align - 1)) & -align; - return num; -} - -static void save_bpf_jit_regs(struct jit_ctx *ctx, unsigned offset) -{ - int i = 0, real_off = 0; - u32 sflags, tmp_flags; - - /* Adjust the stack pointer */ - if (offset) - emit_stack_offset(-align_sp(offset), ctx); - - tmp_flags = sflags = ctx->flags >> SEEN_SREG_SFT; - /* sflags is essentially a bitmap */ - while (tmp_flags) { - if ((sflags >> i) & 0x1) { - emit_store_stack_reg(MIPS_R_S0 + i, r_sp, real_off, - ctx); - real_off += SZREG; - } - i++; - tmp_flags >>= 1; - } - - /* save return address */ - if (ctx->flags & SEEN_CALL) { - emit_store_stack_reg(r_ra, r_sp, real_off, ctx); - real_off += SZREG; - } - - /* Setup r_M leaving the alignment gap if necessary */ - if (ctx->flags & SEEN_MEM) { - if (real_off % (SZREG * 2)) - real_off += SZREG; - emit_long_instr(ctx, ADDIU, r_M, r_sp, real_off); - } -} - -static void restore_bpf_jit_regs(struct jit_ctx *ctx, - unsigned int offset) -{ - int i, real_off = 0; - u32 sflags, tmp_flags; - - tmp_flags = sflags = ctx->flags >> SEEN_SREG_SFT; - /* sflags is a bitmap */ - i = 0; - while (tmp_flags) { - if ((sflags >> i) & 0x1) { - emit_load_stack_reg(MIPS_R_S0 + i, r_sp, real_off, - ctx); - real_off += SZREG; - } - i++; - tmp_flags >>= 1; - } - - /* restore return address */ - if (ctx->flags & SEEN_CALL) - emit_load_stack_reg(r_ra, r_sp, real_off, ctx); - - /* Restore the sp and discard the scrach memory */ - if (offset) - emit_stack_offset(align_sp(offset), ctx); -} - -static unsigned int get_stack_depth(struct jit_ctx *ctx) -{ - int sp_off = 0; - - - /* How may s* regs do we need to preserved? */ - sp_off += hweight32(ctx->flags >> SEEN_SREG_SFT) * SZREG; - - if (ctx->flags & SEEN_MEM) - sp_off += 4 * BPF_MEMWORDS; /* BPF_MEMWORDS are 32-bit */ - - if (ctx->flags & SEEN_CALL) - sp_off += SZREG; /* Space for our ra register */ - - return sp_off; -} - -static void build_prologue(struct jit_ctx *ctx) -{ - int sp_off; - - /* Calculate the total offset for the stack pointer */ - sp_off = get_stack_depth(ctx); - save_bpf_jit_regs(ctx, sp_off); - - if (ctx->flags & SEEN_SKB) - emit_reg_move(r_skb, MIPS_R_A0, ctx); - - if (ctx->flags & SEEN_SKB_DATA) { - /* Load packet length */ - emit_load(r_skb_len, r_skb, offsetof(struct sk_buff, len), - ctx); - emit_load(r_tmp, r_skb, offsetof(struct sk_buff, data_len), - ctx); - /* Load the data pointer */ - emit_load_ptr(r_skb_data, r_skb, - offsetof(struct sk_buff, data), ctx); - /* Load the header length */ - emit_subu(r_skb_hl, r_skb_len, r_tmp, ctx); - } - - if (ctx->flags & SEEN_X) - emit_jit_reg_move(r_X, r_zero, ctx); - - /* - * Do not leak kernel data to userspace, we only need to clear - * r_A if it is ever used. In fact if it is never used, we - * will not save/restore it, so clearing it in this case would - * corrupt the state of the caller. - */ - if (bpf_needs_clear_a(&ctx->skf->insns[0]) && - (ctx->flags & SEEN_A)) - emit_jit_reg_move(r_A, r_zero, ctx); -} - -static void build_epilogue(struct jit_ctx *ctx) -{ - unsigned int sp_off; - - /* Calculate the total offset for the stack pointer */ - - sp_off = get_stack_depth(ctx); - restore_bpf_jit_regs(ctx, sp_off); - - /* Return */ - emit_jr(r_ra, ctx); - emit_nop(ctx); -} - -#define CHOOSE_LOAD_FUNC(K, func) \ - ((int)K < 0 ? ((int)K >= SKF_LL_OFF ? func##_negative : func) : \ - func##_positive) - -static bool is_bad_offset(int b_off) -{ - return b_off > 0x1ffff || b_off < -0x20000; -} - -static int build_body(struct jit_ctx *ctx) -{ - const struct bpf_prog *prog = ctx->skf; - const struct sock_filter *inst; - unsigned int i, off, condt; - u32 k, b_off __maybe_unused; - u8 (*sk_load_func)(unsigned long *skb, int offset); - - for (i = 0; i < prog->len; i++) { - u16 code; - - inst = &(prog->insns[i]); - pr_debug("%s: code->0x%02x, jt->0x%x, jf->0x%x, k->0x%x\n", - __func__, inst->code, inst->jt, inst->jf, inst->k); - k = inst->k; - code = bpf_anc_helper(inst); - - if (ctx->target == NULL) - ctx->offsets[i] = ctx->idx * 4; - - switch (code) { - case BPF_LD | BPF_IMM: - /* A <- k ==> li r_A, k */ - ctx->flags |= SEEN_A; - emit_load_imm(r_A, k, ctx); - break; - case BPF_LD | BPF_W | BPF_LEN: - BUILD_BUG_ON(sizeof_field(struct sk_buff, len) != 4); - /* A <- len ==> lw r_A, offset(skb) */ - ctx->flags |= SEEN_SKB | SEEN_A; - off = offsetof(struct sk_buff, len); - emit_load(r_A, r_skb, off, ctx); - break; - case BPF_LD | BPF_MEM: - /* A <- M[k] ==> lw r_A, offset(M) */ - ctx->flags |= SEEN_MEM | SEEN_A; - emit_load(r_A, r_M, SCRATCH_OFF(k), ctx); - break; - case BPF_LD | BPF_W | BPF_ABS: - /* A <- P[k:4] */ - sk_load_func = CHOOSE_LOAD_FUNC(k, sk_load_word); - goto load; - case BPF_LD | BPF_H | BPF_ABS: - /* A <- P[k:2] */ - sk_load_func = CHOOSE_LOAD_FUNC(k, sk_load_half); - goto load; - case BPF_LD | BPF_B | BPF_ABS: - /* A <- P[k:1] */ - sk_load_func = CHOOSE_LOAD_FUNC(k, sk_load_byte); -load: - emit_load_imm(r_off, k, ctx); -load_common: - ctx->flags |= SEEN_CALL | SEEN_OFF | - SEEN_SKB | SEEN_A | SEEN_SKB_DATA; - - emit_load_func(r_s0, (ptr)sk_load_func, ctx); - emit_reg_move(MIPS_R_A0, r_skb, ctx); - emit_jalr(MIPS_R_RA, r_s0, ctx); - /* Load second argument to delay slot */ - emit_reg_move(MIPS_R_A1, r_off, ctx); - /* Check the error value */ - emit_bcond(MIPS_COND_EQ, r_ret, 0, b_imm(i + 1, ctx), - ctx); - /* Load return register on DS for failures */ - emit_reg_move(r_ret, r_zero, ctx); - /* Return with error */ - b_off = b_imm(prog->len, ctx); - if (is_bad_offset(b_off)) - return -E2BIG; - emit_b(b_off, ctx); - emit_nop(ctx); - break; - case BPF_LD | BPF_W | BPF_IND: - /* A <- P[X + k:4] */ - sk_load_func = sk_load_word; - goto load_ind; - case BPF_LD | BPF_H | BPF_IND: - /* A <- P[X + k:2] */ - sk_load_func = sk_load_half; - goto load_ind; - case BPF_LD | BPF_B | BPF_IND: - /* A <- P[X + k:1] */ - sk_load_func = sk_load_byte; -load_ind: - ctx->flags |= SEEN_OFF | SEEN_X; - emit_addiu(r_off, r_X, k, ctx); - goto load_common; - case BPF_LDX | BPF_IMM: - /* X <- k */ - ctx->flags |= SEEN_X; - emit_load_imm(r_X, k, ctx); - break; - case BPF_LDX | BPF_MEM: - /* X <- M[k] */ - ctx->flags |= SEEN_X | SEEN_MEM; - emit_load(r_X, r_M, SCRATCH_OFF(k), ctx); - break; - case BPF_LDX | BPF_W | BPF_LEN: - /* X <- len */ - ctx->flags |= SEEN_X | SEEN_SKB; - off = offsetof(struct sk_buff, len); - emit_load(r_X, r_skb, off, ctx); - break; - case BPF_LDX | BPF_B | BPF_MSH: - /* X <- 4 * (P[k:1] & 0xf) */ - ctx->flags |= SEEN_X | SEEN_CALL | SEEN_SKB; - /* Load offset to a1 */ - emit_load_func(r_s0, (ptr)sk_load_byte, ctx); - /* - * This may emit two instructions so it may not fit - * in the delay slot. So use a0 in the delay slot. - */ - emit_load_imm(MIPS_R_A1, k, ctx); - emit_jalr(MIPS_R_RA, r_s0, ctx); - emit_reg_move(MIPS_R_A0, r_skb, ctx); /* delay slot */ - /* Check the error value */ - b_off = b_imm(prog->len, ctx); - if (is_bad_offset(b_off)) - return -E2BIG; - emit_bcond(MIPS_COND_NE, r_ret, 0, b_off, ctx); - emit_reg_move(r_ret, r_zero, ctx); - /* We are good */ - /* X <- P[1:K] & 0xf */ - emit_andi(r_X, r_A, 0xf, ctx); - /* X << 2 */ - emit_b(b_imm(i + 1, ctx), ctx); - emit_sll(r_X, r_X, 2, ctx); /* delay slot */ - break; - case BPF_ST: - /* M[k] <- A */ - ctx->flags |= SEEN_MEM | SEEN_A; - emit_store(r_A, r_M, SCRATCH_OFF(k), ctx); - break; - case BPF_STX: - /* M[k] <- X */ - ctx->flags |= SEEN_MEM | SEEN_X; - emit_store(r_X, r_M, SCRATCH_OFF(k), ctx); - break; - case BPF_ALU | BPF_ADD | BPF_K: - /* A += K */ - ctx->flags |= SEEN_A; - emit_addiu(r_A, r_A, k, ctx); - break; - case BPF_ALU | BPF_ADD | BPF_X: - /* A += X */ - ctx->flags |= SEEN_A | SEEN_X; - emit_addu(r_A, r_A, r_X, ctx); - break; - case BPF_ALU | BPF_SUB | BPF_K: - /* A -= K */ - ctx->flags |= SEEN_A; - emit_addiu(r_A, r_A, -k, ctx); - break; - case BPF_ALU | BPF_SUB | BPF_X: - /* A -= X */ - ctx->flags |= SEEN_A | SEEN_X; - emit_subu(r_A, r_A, r_X, ctx); - break; - case BPF_ALU | BPF_MUL | BPF_K: - /* A *= K */ - /* Load K to scratch register before MUL */ - ctx->flags |= SEEN_A; - emit_load_imm(r_s0, k, ctx); - emit_mul(r_A, r_A, r_s0, ctx); - break; - case BPF_ALU | BPF_MUL | BPF_X: - /* A *= X */ - ctx->flags |= SEEN_A | SEEN_X; - emit_mul(r_A, r_A, r_X, ctx); - break; - case BPF_ALU | BPF_DIV | BPF_K: - /* A /= k */ - if (k == 1) - break; - if (optimize_div(&k)) { - ctx->flags |= SEEN_A; - emit_srl(r_A, r_A, k, ctx); - break; - } - ctx->flags |= SEEN_A; - emit_load_imm(r_s0, k, ctx); - emit_div(r_A, r_s0, ctx); - break; - case BPF_ALU | BPF_MOD | BPF_K: - /* A %= k */ - if (k == 1) { - ctx->flags |= SEEN_A; - emit_jit_reg_move(r_A, r_zero, ctx); - } else { - ctx->flags |= SEEN_A; - emit_load_imm(r_s0, k, ctx); - emit_mod(r_A, r_s0, ctx); - } - break; - case BPF_ALU | BPF_DIV | BPF_X: - /* A /= X */ - ctx->flags |= SEEN_X | SEEN_A; - /* Check if r_X is zero */ - b_off = b_imm(prog->len, ctx); - if (is_bad_offset(b_off)) - return -E2BIG; - emit_bcond(MIPS_COND_EQ, r_X, r_zero, b_off, ctx); - emit_load_imm(r_ret, 0, ctx); /* delay slot */ - emit_div(r_A, r_X, ctx); - break; - case BPF_ALU | BPF_MOD | BPF_X: - /* A %= X */ - ctx->flags |= SEEN_X | SEEN_A; - /* Check if r_X is zero */ - b_off = b_imm(prog->len, ctx); - if (is_bad_offset(b_off)) - return -E2BIG; - emit_bcond(MIPS_COND_EQ, r_X, r_zero, b_off, ctx); - emit_load_imm(r_ret, 0, ctx); /* delay slot */ - emit_mod(r_A, r_X, ctx); - break; - case BPF_ALU | BPF_OR | BPF_K: - /* A |= K */ - ctx->flags |= SEEN_A; - emit_ori(r_A, r_A, k, ctx); - break; - case BPF_ALU | BPF_OR | BPF_X: - /* A |= X */ - ctx->flags |= SEEN_A; - emit_ori(r_A, r_A, r_X, ctx); - break; - case BPF_ALU | BPF_XOR | BPF_K: - /* A ^= k */ - ctx->flags |= SEEN_A; - emit_xori(r_A, r_A, k, ctx); - break; - case BPF_ANC | SKF_AD_ALU_XOR_X: - case BPF_ALU | BPF_XOR | BPF_X: - /* A ^= X */ - ctx->flags |= SEEN_A; - emit_xor(r_A, r_A, r_X, ctx); - break; - case BPF_ALU | BPF_AND | BPF_K: - /* A &= K */ - ctx->flags |= SEEN_A; - emit_andi(r_A, r_A, k, ctx); - break; - case BPF_ALU | BPF_AND | BPF_X: - /* A &= X */ - ctx->flags |= SEEN_A | SEEN_X; - emit_and(r_A, r_A, r_X, ctx); - break; - case BPF_ALU | BPF_LSH | BPF_K: - /* A <<= K */ - ctx->flags |= SEEN_A; - emit_sll(r_A, r_A, k, ctx); - break; - case BPF_ALU | BPF_LSH | BPF_X: - /* A <<= X */ - ctx->flags |= SEEN_A | SEEN_X; - emit_sllv(r_A, r_A, r_X, ctx); - break; - case BPF_ALU | BPF_RSH | BPF_K: - /* A >>= K */ - ctx->flags |= SEEN_A; - emit_srl(r_A, r_A, k, ctx); - break; - case BPF_ALU | BPF_RSH | BPF_X: - ctx->flags |= SEEN_A | SEEN_X; - emit_srlv(r_A, r_A, r_X, ctx); - break; - case BPF_ALU | BPF_NEG: - /* A = -A */ - ctx->flags |= SEEN_A; - emit_neg(r_A, ctx); - break; - case BPF_JMP | BPF_JA: - /* pc += K */ - b_off = b_imm(i + k + 1, ctx); - if (is_bad_offset(b_off)) - return -E2BIG; - emit_b(b_off, ctx); - emit_nop(ctx); - break; - case BPF_JMP | BPF_JEQ | BPF_K: - /* pc += ( A == K ) ? pc->jt : pc->jf */ - condt = MIPS_COND_EQ | MIPS_COND_K; - goto jmp_cmp; - case BPF_JMP | BPF_JEQ | BPF_X: - ctx->flags |= SEEN_X; - /* pc += ( A == X ) ? pc->jt : pc->jf */ - condt = MIPS_COND_EQ | MIPS_COND_X; - goto jmp_cmp; - case BPF_JMP | BPF_JGE | BPF_K: - /* pc += ( A >= K ) ? pc->jt : pc->jf */ - condt = MIPS_COND_GE | MIPS_COND_K; - goto jmp_cmp; - case BPF_JMP | BPF_JGE | BPF_X: - ctx->flags |= SEEN_X; - /* pc += ( A >= X ) ? pc->jt : pc->jf */ - condt = MIPS_COND_GE | MIPS_COND_X; - goto jmp_cmp; - case BPF_JMP | BPF_JGT | BPF_K: - /* pc += ( A > K ) ? pc->jt : pc->jf */ - condt = MIPS_COND_GT | MIPS_COND_K; - goto jmp_cmp; - case BPF_JMP | BPF_JGT | BPF_X: - ctx->flags |= SEEN_X; - /* pc += ( A > X ) ? pc->jt : pc->jf */ - condt = MIPS_COND_GT | MIPS_COND_X; -jmp_cmp: - /* Greater or Equal */ - if ((condt & MIPS_COND_GE) || - (condt & MIPS_COND_GT)) { - if (condt & MIPS_COND_K) { /* K */ - ctx->flags |= SEEN_A; - emit_sltiu(r_s0, r_A, k, ctx); - } else { /* X */ - ctx->flags |= SEEN_A | - SEEN_X; - emit_sltu(r_s0, r_A, r_X, ctx); - } - /* A < (K|X) ? r_scrach = 1 */ - b_off = b_imm(i + inst->jf + 1, ctx); - emit_bcond(MIPS_COND_NE, r_s0, r_zero, b_off, - ctx); - emit_nop(ctx); - /* A > (K|X) ? scratch = 0 */ - if (condt & MIPS_COND_GT) { - /* Checking for equality */ - ctx->flags |= SEEN_A | SEEN_X; - if (condt & MIPS_COND_K) - emit_load_imm(r_s0, k, ctx); - else - emit_jit_reg_move(r_s0, r_X, - ctx); - b_off = b_imm(i + inst->jf + 1, ctx); - emit_bcond(MIPS_COND_EQ, r_A, r_s0, - b_off, ctx); - emit_nop(ctx); - /* Finally, A > K|X */ - b_off = b_imm(i + inst->jt + 1, ctx); - emit_b(b_off, ctx); - emit_nop(ctx); - } else { - /* A >= (K|X) so jump */ - b_off = b_imm(i + inst->jt + 1, ctx); - emit_b(b_off, ctx); - emit_nop(ctx); - } - } else { - /* A == K|X */ - if (condt & MIPS_COND_K) { /* K */ - ctx->flags |= SEEN_A; - emit_load_imm(r_s0, k, ctx); - /* jump true */ - b_off = b_imm(i + inst->jt + 1, ctx); - emit_bcond(MIPS_COND_EQ, r_A, r_s0, - b_off, ctx); - emit_nop(ctx); - /* jump false */ - b_off = b_imm(i + inst->jf + 1, - ctx); - emit_bcond(MIPS_COND_NE, r_A, r_s0, - b_off, ctx); - emit_nop(ctx); - } else { /* X */ - /* jump true */ - ctx->flags |= SEEN_A | SEEN_X; - b_off = b_imm(i + inst->jt + 1, - ctx); - emit_bcond(MIPS_COND_EQ, r_A, r_X, - b_off, ctx); - emit_nop(ctx); - /* jump false */ - b_off = b_imm(i + inst->jf + 1, ctx); - emit_bcond(MIPS_COND_NE, r_A, r_X, - b_off, ctx); - emit_nop(ctx); - } - } - break; - case BPF_JMP | BPF_JSET | BPF_K: - ctx->flags |= SEEN_A; - /* pc += (A & K) ? pc -> jt : pc -> jf */ - emit_load_imm(r_s1, k, ctx); - emit_and(r_s0, r_A, r_s1, ctx); - /* jump true */ - b_off = b_imm(i + inst->jt + 1, ctx); - emit_bcond(MIPS_COND_NE, r_s0, r_zero, b_off, ctx); - emit_nop(ctx); - /* jump false */ - b_off = b_imm(i + inst->jf + 1, ctx); - emit_b(b_off, ctx); - emit_nop(ctx); - break; - case BPF_JMP | BPF_JSET | BPF_X: - ctx->flags |= SEEN_X | SEEN_A; - /* pc += (A & X) ? pc -> jt : pc -> jf */ - emit_and(r_s0, r_A, r_X, ctx); - /* jump true */ - b_off = b_imm(i + inst->jt + 1, ctx); - emit_bcond(MIPS_COND_NE, r_s0, r_zero, b_off, ctx); - emit_nop(ctx); - /* jump false */ - b_off = b_imm(i + inst->jf + 1, ctx); - emit_b(b_off, ctx); - emit_nop(ctx); - break; - case BPF_RET | BPF_A: - ctx->flags |= SEEN_A; - if (i != prog->len - 1) { - /* - * If this is not the last instruction - * then jump to the epilogue - */ - b_off = b_imm(prog->len, ctx); - if (is_bad_offset(b_off)) - return -E2BIG; - emit_b(b_off, ctx); - } - emit_reg_move(r_ret, r_A, ctx); /* delay slot */ - break; - case BPF_RET | BPF_K: - /* - * It can emit two instructions so it does not fit on - * the delay slot. - */ - emit_load_imm(r_ret, k, ctx); - if (i != prog->len - 1) { - /* - * If this is not the last instruction - * then jump to the epilogue - */ - b_off = b_imm(prog->len, ctx); - if (is_bad_offset(b_off)) - return -E2BIG; - emit_b(b_off, ctx); - emit_nop(ctx); - } - break; - case BPF_MISC | BPF_TAX: - /* X = A */ - ctx->flags |= SEEN_X | SEEN_A; - emit_jit_reg_move(r_X, r_A, ctx); - break; - case BPF_MISC | BPF_TXA: - /* A = X */ - ctx->flags |= SEEN_A | SEEN_X; - emit_jit_reg_move(r_A, r_X, ctx); - break; - /* AUX */ - case BPF_ANC | SKF_AD_PROTOCOL: - /* A = ntohs(skb->protocol */ - ctx->flags |= SEEN_SKB | SEEN_OFF | SEEN_A; - BUILD_BUG_ON(sizeof_field(struct sk_buff, - protocol) != 2); - off = offsetof(struct sk_buff, protocol); - emit_half_load(r_A, r_skb, off, ctx); -#ifdef CONFIG_CPU_LITTLE_ENDIAN - /* This needs little endian fixup */ - if (cpu_has_wsbh) { - /* R2 and later have the wsbh instruction */ - emit_wsbh(r_A, r_A, ctx); - } else { - /* Get first byte */ - emit_andi(r_tmp_imm, r_A, 0xff, ctx); - /* Shift it */ - emit_sll(r_tmp, r_tmp_imm, 8, ctx); - /* Get second byte */ - emit_srl(r_tmp_imm, r_A, 8, ctx); - emit_andi(r_tmp_imm, r_tmp_imm, 0xff, ctx); - /* Put everyting together in r_A */ - emit_or(r_A, r_tmp, r_tmp_imm, ctx); - } -#endif - break; - case BPF_ANC | SKF_AD_CPU: - ctx->flags |= SEEN_A | SEEN_OFF; - /* A = current_thread_info()->cpu */ - BUILD_BUG_ON(sizeof_field(struct thread_info, - cpu) != 4); - off = offsetof(struct thread_info, cpu); - /* $28/gp points to the thread_info struct */ - emit_load(r_A, 28, off, ctx); - break; - case BPF_ANC | SKF_AD_IFINDEX: - /* A = skb->dev->ifindex */ - case BPF_ANC | SKF_AD_HATYPE: - /* A = skb->dev->type */ - ctx->flags |= SEEN_SKB | SEEN_A; - off = offsetof(struct sk_buff, dev); - /* Load *dev pointer */ - emit_load_ptr(r_s0, r_skb, off, ctx); - /* error (0) in the delay slot */ - b_off = b_imm(prog->len, ctx); - if (is_bad_offset(b_off)) - return -E2BIG; - emit_bcond(MIPS_COND_EQ, r_s0, r_zero, b_off, ctx); - emit_reg_move(r_ret, r_zero, ctx); - if (code == (BPF_ANC | SKF_AD_IFINDEX)) { - BUILD_BUG_ON(sizeof_field(struct net_device, ifindex) != 4); - off = offsetof(struct net_device, ifindex); - emit_load(r_A, r_s0, off, ctx); - } else { /* (code == (BPF_ANC | SKF_AD_HATYPE) */ - BUILD_BUG_ON(sizeof_field(struct net_device, type) != 2); - off = offsetof(struct net_device, type); - emit_half_load_unsigned(r_A, r_s0, off, ctx); - } - break; - case BPF_ANC | SKF_AD_MARK: - ctx->flags |= SEEN_SKB | SEEN_A; - BUILD_BUG_ON(sizeof_field(struct sk_buff, mark) != 4); - off = offsetof(struct sk_buff, mark); - emit_load(r_A, r_skb, off, ctx); - break; - case BPF_ANC | SKF_AD_RXHASH: - ctx->flags |= SEEN_SKB | SEEN_A; - BUILD_BUG_ON(sizeof_field(struct sk_buff, hash) != 4); - off = offsetof(struct sk_buff, hash); - emit_load(r_A, r_skb, off, ctx); - break; - case BPF_ANC | SKF_AD_VLAN_TAG: - ctx->flags |= SEEN_SKB | SEEN_A; - BUILD_BUG_ON(sizeof_field(struct sk_buff, - vlan_tci) != 2); - off = offsetof(struct sk_buff, vlan_tci); - emit_half_load_unsigned(r_A, r_skb, off, ctx); - break; - case BPF_ANC | SKF_AD_VLAN_TAG_PRESENT: - ctx->flags |= SEEN_SKB | SEEN_A; - emit_load_byte(r_A, r_skb, PKT_VLAN_PRESENT_OFFSET(), ctx); - if (PKT_VLAN_PRESENT_BIT) - emit_srl(r_A, r_A, PKT_VLAN_PRESENT_BIT, ctx); - if (PKT_VLAN_PRESENT_BIT < 7) - emit_andi(r_A, r_A, 1, ctx); - break; - case BPF_ANC | SKF_AD_PKTTYPE: - ctx->flags |= SEEN_SKB; - - emit_load_byte(r_tmp, r_skb, PKT_TYPE_OFFSET(), ctx); - /* Keep only the last 3 bits */ - emit_andi(r_A, r_tmp, PKT_TYPE_MAX, ctx); -#ifdef __BIG_ENDIAN_BITFIELD - /* Get the actual packet type to the lower 3 bits */ - emit_srl(r_A, r_A, 5, ctx); -#endif - break; - case BPF_ANC | SKF_AD_QUEUE: - ctx->flags |= SEEN_SKB | SEEN_A; - BUILD_BUG_ON(sizeof_field(struct sk_buff, - queue_mapping) != 2); - BUILD_BUG_ON(offsetof(struct sk_buff, - queue_mapping) > 0xff); - off = offsetof(struct sk_buff, queue_mapping); - emit_half_load_unsigned(r_A, r_skb, off, ctx); - break; - default: - pr_debug("%s: Unhandled opcode: 0x%02x\n", __FILE__, - inst->code); - return -1; - } - } - - /* compute offsets only during the first pass */ - if (ctx->target == NULL) - ctx->offsets[i] = ctx->idx * 4; - - return 0; -} - -void bpf_jit_compile(struct bpf_prog *fp) -{ - struct jit_ctx ctx; - unsigned int alloc_size, tmp_idx; - - if (!bpf_jit_enable) - return; - - memset(&ctx, 0, sizeof(ctx)); - - ctx.offsets = kcalloc(fp->len + 1, sizeof(*ctx.offsets), GFP_KERNEL); - if (ctx.offsets == NULL) - return; - - ctx.skf = fp; - - if (build_body(&ctx)) - goto out; - - tmp_idx = ctx.idx; - build_prologue(&ctx); - ctx.prologue_bytes = (ctx.idx - tmp_idx) * 4; - /* just to complete the ctx.idx count */ - build_epilogue(&ctx); - - alloc_size = 4 * ctx.idx; - ctx.target = module_alloc(alloc_size); - if (ctx.target == NULL) - goto out; - - /* Clean it */ - memset(ctx.target, 0, alloc_size); - - ctx.idx = 0; - - /* Generate the actual JIT code */ - build_prologue(&ctx); - if (build_body(&ctx)) { - module_memfree(ctx.target); - goto out; - } - build_epilogue(&ctx); - - /* Update the icache */ - flush_icache_range((ptr)ctx.target, (ptr)(ctx.target + ctx.idx)); - - if (bpf_jit_enable > 1) - /* Dump JIT code */ - bpf_jit_dump(fp->len, alloc_size, 2, ctx.target); - - fp->bpf_func = (void *)ctx.target; - fp->jited = 1; - -out: - kfree(ctx.offsets); -} - -void bpf_jit_free(struct bpf_prog *fp) -{ - if (fp->jited) - module_memfree(fp->bpf_func); - - bpf_prog_unlock_free(fp); -} diff --git a/arch/mips/net/bpf_jit.h b/arch/mips/net/bpf_jit.h deleted file mode 100644 index 166ca06c9da9..000000000000 --- 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 - */ - -#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 */ diff --git a/arch/mips/net/bpf_jit_asm.S b/arch/mips/net/bpf_jit_asm.S deleted file mode 100644 index 57154c5883b6..000000000000 --- 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 - * - * 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 -#include -#include -#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/arch/mips/net/ebpf_jit.c b/arch/mips/net/ebpf_jit.c deleted file mode 100644 index 3a73e9375712..000000000000 --- a/arch/mips/net/ebpf_jit.c +++ /dev/null @@ -1,1938 +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 - */ - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -/* 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; - int tcc_reg; - - 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 */ - tcc_reg = (ctx->flags & EBPF_TCC_IN_V1) ? MIPS_R_V1 : MIPS_R_S4; - emit_instr(ctx, daddiu, MIPS_R_T5, tcc_reg, -1); - b_off = b_imm(this_idx + 1, ctx); - emit_instr(ctx, bltz, tcc_reg, 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_NOSPEC: /* speculation barrier */ - 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_ATOMIC: - case BPF_STX | BPF_DW | BPF_ATOMIC: - 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_ATOMIC) { - if (insn->imm != BPF_ADD) { - pr_err("ATOMIC OP %02x NOT HANDLED\n", insn->imm); - return -EINVAL; - } - - /* - * 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) - 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; -} -- cgit