diff options
Diffstat (limited to 'arch/riscv/net/bpf_jit_comp64.c')
| -rw-r--r-- | arch/riscv/net/bpf_jit_comp64.c | 1103 |
1 files changed, 1103 insertions, 0 deletions
diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c new file mode 100644 index 000000000000..cc1985d8750a --- /dev/null +++ b/arch/riscv/net/bpf_jit_comp64.c @@ -0,0 +1,1103 @@ +// SPDX-License-Identifier: GPL-2.0 +/* BPF JIT compiler for RV64G + * + * Copyright(c) 2019 Björn Töpel <bjorn.topel@gmail.com> + * + */ + +#include <linux/bpf.h> +#include <linux/filter.h> +#include "bpf_jit.h" + +#define RV_REG_TCC RV_REG_A6 +#define RV_REG_TCC_SAVED RV_REG_S6 /* Store A6 in S6 if program do calls */ + +static const int regmap[] = { + [BPF_REG_0] = RV_REG_A5, + [BPF_REG_1] = RV_REG_A0, + [BPF_REG_2] = RV_REG_A1, + [BPF_REG_3] = RV_REG_A2, + [BPF_REG_4] = RV_REG_A3, + [BPF_REG_5] = RV_REG_A4, + [BPF_REG_6] = RV_REG_S1, + [BPF_REG_7] = RV_REG_S2, + [BPF_REG_8] = RV_REG_S3, + [BPF_REG_9] = RV_REG_S4, + [BPF_REG_FP] = RV_REG_S5, + [BPF_REG_AX] = RV_REG_T0, +}; + +enum { + RV_CTX_F_SEEN_TAIL_CALL = 0, + RV_CTX_F_SEEN_CALL = RV_REG_RA, + RV_CTX_F_SEEN_S1 = RV_REG_S1, + RV_CTX_F_SEEN_S2 = RV_REG_S2, + RV_CTX_F_SEEN_S3 = RV_REG_S3, + RV_CTX_F_SEEN_S4 = RV_REG_S4, + RV_CTX_F_SEEN_S5 = RV_REG_S5, + RV_CTX_F_SEEN_S6 = RV_REG_S6, +}; + +static u8 bpf_to_rv_reg(int bpf_reg, struct rv_jit_context *ctx) +{ + u8 reg = regmap[bpf_reg]; + + switch (reg) { + case RV_CTX_F_SEEN_S1: + case RV_CTX_F_SEEN_S2: + case RV_CTX_F_SEEN_S3: + case RV_CTX_F_SEEN_S4: + case RV_CTX_F_SEEN_S5: + case RV_CTX_F_SEEN_S6: + __set_bit(reg, &ctx->flags); + } + return reg; +}; + +static bool seen_reg(int reg, struct rv_jit_context *ctx) +{ + switch (reg) { + case RV_CTX_F_SEEN_CALL: + case RV_CTX_F_SEEN_S1: + case RV_CTX_F_SEEN_S2: + case RV_CTX_F_SEEN_S3: + case RV_CTX_F_SEEN_S4: + case RV_CTX_F_SEEN_S5: + case RV_CTX_F_SEEN_S6: + return test_bit(reg, &ctx->flags); + } + return false; +} + +static void mark_fp(struct rv_jit_context *ctx) +{ + __set_bit(RV_CTX_F_SEEN_S5, &ctx->flags); +} + +static void mark_call(struct rv_jit_context *ctx) +{ + __set_bit(RV_CTX_F_SEEN_CALL, &ctx->flags); +} + +static bool seen_call(struct rv_jit_context *ctx) +{ + return test_bit(RV_CTX_F_SEEN_CALL, &ctx->flags); +} + +static void mark_tail_call(struct rv_jit_context *ctx) +{ + __set_bit(RV_CTX_F_SEEN_TAIL_CALL, &ctx->flags); +} + +static bool seen_tail_call(struct rv_jit_context *ctx) +{ + return test_bit(RV_CTX_F_SEEN_TAIL_CALL, &ctx->flags); +} + +static u8 rv_tail_call_reg(struct rv_jit_context *ctx) +{ + mark_tail_call(ctx); + + if (seen_call(ctx)) { + __set_bit(RV_CTX_F_SEEN_S6, &ctx->flags); + return RV_REG_S6; + } + return RV_REG_A6; +} + +static bool is_32b_int(s64 val) +{ + return -(1L << 31) <= val && val < (1L << 31); +} + +static void emit_imm(u8 rd, s64 val, struct rv_jit_context *ctx) +{ + /* Note that the immediate from the add is sign-extended, + * which means that we need to compensate this by adding 2^12, + * when the 12th bit is set. A simpler way of doing this, and + * getting rid of the check, is to just add 2**11 before the + * shift. The "Loading a 32-Bit constant" example from the + * "Computer Organization and Design, RISC-V edition" book by + * Patterson/Hennessy highlights this fact. + * + * This also means that we need to process LSB to MSB. + */ + s64 upper = (val + (1 << 11)) >> 12, lower = val & 0xfff; + int shift; + + if (is_32b_int(val)) { + if (upper) + emit(rv_lui(rd, upper), ctx); + + if (!upper) { + emit(rv_addi(rd, RV_REG_ZERO, lower), ctx); + return; + } + + emit(rv_addiw(rd, rd, lower), ctx); + return; + } + + shift = __ffs(upper); + upper >>= shift; + shift += 12; + + emit_imm(rd, upper, ctx); + + emit(rv_slli(rd, rd, shift), ctx); + if (lower) + emit(rv_addi(rd, rd, lower), ctx); +} + +static void __build_epilogue(bool is_tail_call, struct rv_jit_context *ctx) +{ + int stack_adjust = ctx->stack_size, store_offset = stack_adjust - 8; + + if (seen_reg(RV_REG_RA, ctx)) { + emit(rv_ld(RV_REG_RA, store_offset, RV_REG_SP), ctx); + store_offset -= 8; + } + emit(rv_ld(RV_REG_FP, store_offset, RV_REG_SP), ctx); + store_offset -= 8; + if (seen_reg(RV_REG_S1, ctx)) { + emit(rv_ld(RV_REG_S1, store_offset, RV_REG_SP), ctx); + store_offset -= 8; + } + if (seen_reg(RV_REG_S2, ctx)) { + emit(rv_ld(RV_REG_S2, store_offset, RV_REG_SP), ctx); + store_offset -= 8; + } + if (seen_reg(RV_REG_S3, ctx)) { + emit(rv_ld(RV_REG_S3, store_offset, RV_REG_SP), ctx); + store_offset -= 8; + } + if (seen_reg(RV_REG_S4, ctx)) { + emit(rv_ld(RV_REG_S4, store_offset, RV_REG_SP), ctx); + store_offset -= 8; + } + if (seen_reg(RV_REG_S5, ctx)) { + emit(rv_ld(RV_REG_S5, store_offset, RV_REG_SP), ctx); + store_offset -= 8; + } + if (seen_reg(RV_REG_S6, ctx)) { + emit(rv_ld(RV_REG_S6, store_offset, RV_REG_SP), ctx); + store_offset -= 8; + } + + emit(rv_addi(RV_REG_SP, RV_REG_SP, stack_adjust), ctx); + /* Set return value. */ + if (!is_tail_call) + emit(rv_addi(RV_REG_A0, RV_REG_A5, 0), ctx); + emit(rv_jalr(RV_REG_ZERO, is_tail_call ? RV_REG_T3 : RV_REG_RA, + is_tail_call ? 4 : 0), /* skip TCC init */ + ctx); +} + +static void emit_bcc(u8 cond, u8 rd, u8 rs, int rvoff, + struct rv_jit_context *ctx) +{ + switch (cond) { + case BPF_JEQ: + emit(rv_beq(rd, rs, rvoff >> 1), ctx); + return; + case BPF_JGT: + emit(rv_bltu(rs, rd, rvoff >> 1), ctx); + return; + case BPF_JLT: + emit(rv_bltu(rd, rs, rvoff >> 1), ctx); + return; + case BPF_JGE: + emit(rv_bgeu(rd, rs, rvoff >> 1), ctx); + return; + case BPF_JLE: + emit(rv_bgeu(rs, rd, rvoff >> 1), ctx); + return; + case BPF_JNE: + emit(rv_bne(rd, rs, rvoff >> 1), ctx); + return; + case BPF_JSGT: + emit(rv_blt(rs, rd, rvoff >> 1), ctx); + return; + case BPF_JSLT: + emit(rv_blt(rd, rs, rvoff >> 1), ctx); + return; + case BPF_JSGE: + emit(rv_bge(rd, rs, rvoff >> 1), ctx); + return; + case BPF_JSLE: + emit(rv_bge(rs, rd, rvoff >> 1), ctx); + } +} + +static void emit_branch(u8 cond, u8 rd, u8 rs, int rvoff, + struct rv_jit_context *ctx) +{ + s64 upper, lower; + + if (is_13b_int(rvoff)) { + emit_bcc(cond, rd, rs, rvoff, ctx); + return; + } + + /* Adjust for jal */ + rvoff -= 4; + + /* Transform, e.g.: + * bne rd,rs,foo + * to + * beq rd,rs,<.L1> + * (auipc foo) + * jal(r) foo + * .L1 + */ + cond = invert_bpf_cond(cond); + if (is_21b_int(rvoff)) { + emit_bcc(cond, rd, rs, 8, ctx); + emit(rv_jal(RV_REG_ZERO, rvoff >> 1), ctx); + return; + } + + /* 32b No need for an additional rvoff adjustment, since we + * get that from the auipc at PC', where PC = PC' + 4. + */ + upper = (rvoff + (1 << 11)) >> 12; + lower = rvoff & 0xfff; + + emit_bcc(cond, rd, rs, 12, ctx); + emit(rv_auipc(RV_REG_T1, upper), ctx); + emit(rv_jalr(RV_REG_ZERO, RV_REG_T1, lower), ctx); +} + +static void emit_zext_32(u8 reg, struct rv_jit_context *ctx) +{ + emit(rv_slli(reg, reg, 32), ctx); + emit(rv_srli(reg, reg, 32), ctx); +} + +static int emit_bpf_tail_call(int insn, struct rv_jit_context *ctx) +{ + int tc_ninsn, off, start_insn = ctx->ninsns; + u8 tcc = rv_tail_call_reg(ctx); + + /* a0: &ctx + * a1: &array + * a2: index + * + * if (index >= array->map.max_entries) + * goto out; + */ + tc_ninsn = insn ? ctx->offset[insn] - ctx->offset[insn - 1] : + ctx->offset[0]; + emit_zext_32(RV_REG_A2, ctx); + + off = offsetof(struct bpf_array, map.max_entries); + if (is_12b_check(off, insn)) + return -1; + emit(rv_lwu(RV_REG_T1, off, RV_REG_A1), ctx); + off = (tc_ninsn - (ctx->ninsns - start_insn)) << 2; + emit_branch(BPF_JGE, RV_REG_A2, RV_REG_T1, off, ctx); + + /* if (TCC-- < 0) + * goto out; + */ + emit(rv_addi(RV_REG_T1, tcc, -1), ctx); + off = (tc_ninsn - (ctx->ninsns - start_insn)) << 2; + emit_branch(BPF_JSLT, tcc, RV_REG_ZERO, off, ctx); + + /* prog = array->ptrs[index]; + * if (!prog) + * goto out; + */ + emit(rv_slli(RV_REG_T2, RV_REG_A2, 3), ctx); + emit(rv_add(RV_REG_T2, RV_REG_T2, RV_REG_A1), ctx); + off = offsetof(struct bpf_array, ptrs); + if (is_12b_check(off, insn)) + return -1; + emit(rv_ld(RV_REG_T2, off, RV_REG_T2), ctx); + off = (tc_ninsn - (ctx->ninsns - start_insn)) << 2; + emit_branch(BPF_JEQ, RV_REG_T2, RV_REG_ZERO, off, ctx); + + /* goto *(prog->bpf_func + 4); */ + off = offsetof(struct bpf_prog, bpf_func); + if (is_12b_check(off, insn)) + return -1; + emit(rv_ld(RV_REG_T3, off, RV_REG_T2), ctx); + emit(rv_addi(RV_REG_TCC, RV_REG_T1, 0), ctx); + __build_epilogue(true, ctx); + return 0; +} + +static void init_regs(u8 *rd, u8 *rs, const struct bpf_insn *insn, + struct rv_jit_context *ctx) +{ + u8 code = insn->code; + + switch (code) { + case BPF_JMP | BPF_JA: + case BPF_JMP | BPF_CALL: + case BPF_JMP | BPF_EXIT: + case BPF_JMP | BPF_TAIL_CALL: + break; + default: + *rd = bpf_to_rv_reg(insn->dst_reg, ctx); + } + + if (code & (BPF_ALU | BPF_X) || code & (BPF_ALU64 | BPF_X) || + code & (BPF_JMP | BPF_X) || code & (BPF_JMP32 | BPF_X) || + code & BPF_LDX || code & BPF_STX) + *rs = bpf_to_rv_reg(insn->src_reg, ctx); +} + +static void emit_zext_32_rd_rs(u8 *rd, u8 *rs, struct rv_jit_context *ctx) +{ + emit(rv_addi(RV_REG_T2, *rd, 0), ctx); + emit_zext_32(RV_REG_T2, ctx); + emit(rv_addi(RV_REG_T1, *rs, 0), ctx); + emit_zext_32(RV_REG_T1, ctx); + *rd = RV_REG_T2; + *rs = RV_REG_T1; +} + +static void emit_sext_32_rd_rs(u8 *rd, u8 *rs, struct rv_jit_context *ctx) +{ + emit(rv_addiw(RV_REG_T2, *rd, 0), ctx); + emit(rv_addiw(RV_REG_T1, *rs, 0), ctx); + *rd = RV_REG_T2; + *rs = RV_REG_T1; +} + +static void emit_zext_32_rd_t1(u8 *rd, struct rv_jit_context *ctx) +{ + emit(rv_addi(RV_REG_T2, *rd, 0), ctx); + emit_zext_32(RV_REG_T2, ctx); + emit_zext_32(RV_REG_T1, ctx); + *rd = RV_REG_T2; +} + +static void emit_sext_32_rd(u8 *rd, struct rv_jit_context *ctx) +{ + emit(rv_addiw(RV_REG_T2, *rd, 0), ctx); + *rd = RV_REG_T2; +} + +static void emit_jump_and_link(u8 rd, s64 rvoff, bool force_jalr, + struct rv_jit_context *ctx) +{ + s64 upper, lower; + + if (rvoff && is_21b_int(rvoff) && !force_jalr) { + emit(rv_jal(rd, rvoff >> 1), ctx); + return; + } + + upper = (rvoff + (1 << 11)) >> 12; + lower = rvoff & 0xfff; + emit(rv_auipc(RV_REG_T1, upper), ctx); + emit(rv_jalr(rd, RV_REG_T1, lower), ctx); +} + +static bool is_signed_bpf_cond(u8 cond) +{ + return cond == BPF_JSGT || cond == BPF_JSLT || + cond == BPF_JSGE || cond == BPF_JSLE; +} + +static int emit_call(bool fixed, u64 addr, struct rv_jit_context *ctx) +{ + s64 off = 0; + u64 ip; + u8 rd; + + if (addr && ctx->insns) { + ip = (u64)(long)(ctx->insns + ctx->ninsns); + off = addr - ip; + if (!is_32b_int(off)) { + pr_err("bpf-jit: target call addr %pK is out of range\n", + (void *)addr); + return -ERANGE; + } + } + + emit_jump_and_link(RV_REG_RA, off, !fixed, ctx); + rd = bpf_to_rv_reg(BPF_REG_0, ctx); + emit(rv_addi(rd, RV_REG_A0, 0), ctx); + return 0; +} + +int bpf_jit_emit_insn(const struct bpf_insn *insn, struct rv_jit_context *ctx, + bool extra_pass) +{ + bool is64 = BPF_CLASS(insn->code) == BPF_ALU64 || + BPF_CLASS(insn->code) == BPF_JMP; + int s, e, rvoff, i = insn - ctx->prog->insnsi; + struct bpf_prog_aux *aux = ctx->prog->aux; + u8 rd = -1, rs = -1, code = insn->code; + s16 off = insn->off; + s32 imm = insn->imm; + + init_regs(&rd, &rs, insn, ctx); + + switch (code) { + /* dst = src */ + case BPF_ALU | BPF_MOV | BPF_X: + case BPF_ALU64 | BPF_MOV | BPF_X: + if (imm == 1) { + /* Special mov32 for zext */ + emit_zext_32(rd, ctx); + break; + } + emit(is64 ? rv_addi(rd, rs, 0) : rv_addiw(rd, rs, 0), ctx); + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + + /* dst = dst OP src */ + case BPF_ALU | BPF_ADD | BPF_X: + case BPF_ALU64 | BPF_ADD | BPF_X: + emit(is64 ? rv_add(rd, rd, rs) : rv_addw(rd, rd, rs), ctx); + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_SUB | BPF_X: + case BPF_ALU64 | BPF_SUB | BPF_X: + emit(is64 ? rv_sub(rd, rd, rs) : rv_subw(rd, rd, rs), ctx); + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_AND | BPF_X: + case BPF_ALU64 | BPF_AND | BPF_X: + emit(rv_and(rd, rd, rs), ctx); + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_OR | BPF_X: + case BPF_ALU64 | BPF_OR | BPF_X: + emit(rv_or(rd, rd, rs), ctx); + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_XOR | BPF_X: + case BPF_ALU64 | BPF_XOR | BPF_X: + emit(rv_xor(rd, rd, rs), ctx); + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_MUL | BPF_X: + case BPF_ALU64 | BPF_MUL | BPF_X: + emit(is64 ? rv_mul(rd, rd, rs) : rv_mulw(rd, rd, rs), ctx); + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_DIV | BPF_X: + case BPF_ALU64 | BPF_DIV | BPF_X: + emit(is64 ? rv_divu(rd, rd, rs) : rv_divuw(rd, rd, rs), ctx); + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_MOD | BPF_X: + case BPF_ALU64 | BPF_MOD | BPF_X: + emit(is64 ? rv_remu(rd, rd, rs) : rv_remuw(rd, rd, rs), ctx); + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_LSH | BPF_X: + case BPF_ALU64 | BPF_LSH | BPF_X: + emit(is64 ? rv_sll(rd, rd, rs) : rv_sllw(rd, rd, rs), ctx); + if (!is64) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_RSH | BPF_X: + case BPF_ALU64 | BPF_RSH | BPF_X: + emit(is64 ? rv_srl(rd, rd, rs) : rv_srlw(rd, rd, rs), ctx); + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_ARSH | BPF_X: + case BPF_ALU64 | BPF_ARSH | BPF_X: + emit(is64 ? rv_sra(rd, rd, rs) : rv_sraw(rd, rd, rs), ctx); + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + + /* dst = -dst */ + case BPF_ALU | BPF_NEG: + case BPF_ALU64 | BPF_NEG: + emit(is64 ? rv_sub(rd, RV_REG_ZERO, rd) : + rv_subw(rd, RV_REG_ZERO, rd), ctx); + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + + /* dst = BSWAP##imm(dst) */ + case BPF_ALU | BPF_END | BPF_FROM_LE: + { + int shift = 64 - imm; + + emit(rv_slli(rd, rd, shift), ctx); + emit(rv_srli(rd, rd, shift), ctx); + break; + } + case BPF_ALU | BPF_END | BPF_FROM_BE: + emit(rv_addi(RV_REG_T2, RV_REG_ZERO, 0), ctx); + + emit(rv_andi(RV_REG_T1, rd, 0xff), ctx); + emit(rv_add(RV_REG_T2, RV_REG_T2, RV_REG_T1), ctx); + emit(rv_slli(RV_REG_T2, RV_REG_T2, 8), ctx); + emit(rv_srli(rd, rd, 8), ctx); + if (imm == 16) + goto out_be; + + emit(rv_andi(RV_REG_T1, rd, 0xff), ctx); + emit(rv_add(RV_REG_T2, RV_REG_T2, RV_REG_T1), ctx); + emit(rv_slli(RV_REG_T2, RV_REG_T2, 8), ctx); + emit(rv_srli(rd, rd, 8), ctx); + + emit(rv_andi(RV_REG_T1, rd, 0xff), ctx); + emit(rv_add(RV_REG_T2, RV_REG_T2, RV_REG_T1), ctx); + emit(rv_slli(RV_REG_T2, RV_REG_T2, 8), ctx); + emit(rv_srli(rd, rd, 8), ctx); + if (imm == 32) + goto out_be; + + emit(rv_andi(RV_REG_T1, rd, 0xff), ctx); + emit(rv_add(RV_REG_T2, RV_REG_T2, RV_REG_T1), ctx); + emit(rv_slli(RV_REG_T2, RV_REG_T2, 8), ctx); + emit(rv_srli(rd, rd, 8), ctx); + + emit(rv_andi(RV_REG_T1, rd, 0xff), ctx); + emit(rv_add(RV_REG_T2, RV_REG_T2, RV_REG_T1), ctx); + emit(rv_slli(RV_REG_T2, RV_REG_T2, 8), ctx); + emit(rv_srli(rd, rd, 8), ctx); + + emit(rv_andi(RV_REG_T1, rd, 0xff), ctx); + emit(rv_add(RV_REG_T2, RV_REG_T2, RV_REG_T1), ctx); + emit(rv_slli(RV_REG_T2, RV_REG_T2, 8), ctx); + emit(rv_srli(rd, rd, 8), ctx); + + emit(rv_andi(RV_REG_T1, rd, 0xff), ctx); + emit(rv_add(RV_REG_T2, RV_REG_T2, RV_REG_T1), ctx); + emit(rv_slli(RV_REG_T2, RV_REG_T2, 8), ctx); + emit(rv_srli(rd, rd, 8), ctx); +out_be: + emit(rv_andi(RV_REG_T1, rd, 0xff), ctx); + emit(rv_add(RV_REG_T2, RV_REG_T2, RV_REG_T1), ctx); + + emit(rv_addi(rd, RV_REG_T2, 0), ctx); + break; + + /* dst = imm */ + case BPF_ALU | BPF_MOV | BPF_K: + case BPF_ALU64 | BPF_MOV | BPF_K: + emit_imm(rd, imm, ctx); + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + + /* dst = dst OP imm */ + case BPF_ALU | BPF_ADD | BPF_K: + case BPF_ALU64 | BPF_ADD | BPF_K: + if (is_12b_int(imm)) { + emit(is64 ? rv_addi(rd, rd, imm) : + rv_addiw(rd, rd, imm), ctx); + } else { + emit_imm(RV_REG_T1, imm, ctx); + emit(is64 ? rv_add(rd, rd, RV_REG_T1) : + rv_addw(rd, rd, RV_REG_T1), ctx); + } + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_SUB | BPF_K: + case BPF_ALU64 | BPF_SUB | BPF_K: + if (is_12b_int(-imm)) { + emit(is64 ? rv_addi(rd, rd, -imm) : + rv_addiw(rd, rd, -imm), ctx); + } else { + emit_imm(RV_REG_T1, imm, ctx); + emit(is64 ? rv_sub(rd, rd, RV_REG_T1) : + rv_subw(rd, rd, RV_REG_T1), ctx); + } + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_AND | BPF_K: + case BPF_ALU64 | BPF_AND | BPF_K: + if (is_12b_int(imm)) { + emit(rv_andi(rd, rd, imm), ctx); + } else { + emit_imm(RV_REG_T1, imm, ctx); + emit(rv_and(rd, rd, RV_REG_T1), ctx); + } + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_OR | BPF_K: + case BPF_ALU64 | BPF_OR | BPF_K: + if (is_12b_int(imm)) { + emit(rv_ori(rd, rd, imm), ctx); + } else { + emit_imm(RV_REG_T1, imm, ctx); + emit(rv_or(rd, rd, RV_REG_T1), ctx); + } + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_XOR | BPF_K: + case BPF_ALU64 | BPF_XOR | BPF_K: + if (is_12b_int(imm)) { + emit(rv_xori(rd, rd, imm), ctx); + } else { + emit_imm(RV_REG_T1, imm, ctx); + emit(rv_xor(rd, rd, RV_REG_T1), ctx); + } + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_MUL | BPF_K: + case BPF_ALU64 | BPF_MUL | BPF_K: + emit_imm(RV_REG_T1, imm, ctx); + emit(is64 ? rv_mul(rd, rd, RV_REG_T1) : + rv_mulw(rd, rd, RV_REG_T1), ctx); + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_DIV | BPF_K: + case BPF_ALU64 | BPF_DIV | BPF_K: + emit_imm(RV_REG_T1, imm, ctx); + emit(is64 ? rv_divu(rd, rd, RV_REG_T1) : + rv_divuw(rd, rd, RV_REG_T1), ctx); + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_MOD | BPF_K: + case BPF_ALU64 | BPF_MOD | BPF_K: + emit_imm(RV_REG_T1, imm, ctx); + emit(is64 ? rv_remu(rd, rd, RV_REG_T1) : + rv_remuw(rd, rd, RV_REG_T1), ctx); + if (!is64 && !aux->verifier_zext) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_LSH | BPF_K: + case BPF_ALU64 | BPF_LSH | BPF_K: + emit(is64 ? rv_slli(rd, rd, imm) : rv_slliw(rd, rd, imm), ctx); + if (!is64) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_RSH | BPF_K: + case BPF_ALU64 | BPF_RSH | BPF_K: + emit(is64 ? rv_srli(rd, rd, imm) : rv_srliw(rd, rd, imm), ctx); + if (!is64) + emit_zext_32(rd, ctx); + break; + case BPF_ALU | BPF_ARSH | BPF_K: + case BPF_ALU64 | BPF_ARSH | BPF_K: + emit(is64 ? rv_srai(rd, rd, imm) : rv_sraiw(rd, rd, imm), ctx); + if (!is64) + emit_zext_32(rd, ctx); + break; + + /* JUMP off */ + case BPF_JMP | BPF_JA: + rvoff = rv_offset(i, off, ctx); + emit_jump_and_link(RV_REG_ZERO, rvoff, false, ctx); + break; + + /* IF (dst COND src) JUMP off */ + case BPF_JMP | BPF_JEQ | BPF_X: + case BPF_JMP32 | BPF_JEQ | BPF_X: + case BPF_JMP | BPF_JGT | BPF_X: + case BPF_JMP32 | BPF_JGT | BPF_X: + case BPF_JMP | BPF_JLT | BPF_X: + case BPF_JMP32 | BPF_JLT | BPF_X: + case BPF_JMP | BPF_JGE | BPF_X: + case BPF_JMP32 | BPF_JGE | BPF_X: + case BPF_JMP | BPF_JLE | BPF_X: + case BPF_JMP32 | BPF_JLE | BPF_X: + case BPF_JMP | BPF_JNE | BPF_X: + case BPF_JMP32 | BPF_JNE | BPF_X: + case BPF_JMP | BPF_JSGT | BPF_X: + case BPF_JMP32 | BPF_JSGT | BPF_X: + case BPF_JMP | BPF_JSLT | BPF_X: + case BPF_JMP32 | BPF_JSLT | BPF_X: + case BPF_JMP | BPF_JSGE | BPF_X: + case BPF_JMP32 | BPF_JSGE | BPF_X: + case BPF_JMP | BPF_JSLE | BPF_X: + case BPF_JMP32 | BPF_JSLE | BPF_X: + case BPF_JMP | BPF_JSET | BPF_X: + case BPF_JMP32 | BPF_JSET | BPF_X: + rvoff = rv_offset(i, off, ctx); + if (!is64) { + s = ctx->ninsns; + if (is_signed_bpf_cond(BPF_OP(code))) + emit_sext_32_rd_rs(&rd, &rs, ctx); + else + emit_zext_32_rd_rs(&rd, &rs, ctx); + e = ctx->ninsns; + + /* Adjust for extra insns */ + rvoff -= (e - s) << 2; + } + + if (BPF_OP(code) == BPF_JSET) { + /* Adjust for and */ + rvoff -= 4; + emit(rv_and(RV_REG_T1, rd, rs), ctx); + emit_branch(BPF_JNE, RV_REG_T1, RV_REG_ZERO, rvoff, + ctx); + } else { + emit_branch(BPF_OP(code), rd, rs, rvoff, ctx); + } + break; + + /* IF (dst COND imm) JUMP off */ + case BPF_JMP | BPF_JEQ | BPF_K: + case BPF_JMP32 | BPF_JEQ | BPF_K: + case BPF_JMP | BPF_JGT | BPF_K: + case BPF_JMP32 | BPF_JGT | BPF_K: + case BPF_JMP | BPF_JLT | BPF_K: + case BPF_JMP32 | BPF_JLT | BPF_K: + case BPF_JMP | BPF_JGE | BPF_K: + case BPF_JMP32 | BPF_JGE | BPF_K: + case BPF_JMP | BPF_JLE | BPF_K: + case BPF_JMP32 | BPF_JLE | BPF_K: + case BPF_JMP | BPF_JNE | BPF_K: + case BPF_JMP32 | BPF_JNE | BPF_K: + case BPF_JMP | BPF_JSGT | BPF_K: + case BPF_JMP32 | BPF_JSGT | BPF_K: + case BPF_JMP | BPF_JSLT | BPF_K: + case BPF_JMP32 | BPF_JSLT | BPF_K: + case BPF_JMP | BPF_JSGE | BPF_K: + case BPF_JMP32 | BPF_JSGE | BPF_K: + case BPF_JMP | BPF_JSLE | BPF_K: + case BPF_JMP32 | BPF_JSLE | BPF_K: + case BPF_JMP | BPF_JSET | BPF_K: + case BPF_JMP32 | BPF_JSET | BPF_K: + rvoff = rv_offset(i, off, ctx); + s = ctx->ninsns; + emit_imm(RV_REG_T1, imm, ctx); + if (!is64) { + if (is_signed_bpf_cond(BPF_OP(code))) + emit_sext_32_rd(&rd, ctx); + else + emit_zext_32_rd_t1(&rd, ctx); + } + e = ctx->ninsns; + + /* Adjust for extra insns */ + rvoff -= (e - s) << 2; + + if (BPF_OP(code) == BPF_JSET) { + /* Adjust for and */ + rvoff -= 4; + emit(rv_and(RV_REG_T1, rd, RV_REG_T1), ctx); + emit_branch(BPF_JNE, RV_REG_T1, RV_REG_ZERO, rvoff, + ctx); + } else { + emit_branch(BPF_OP(code), rd, RV_REG_T1, rvoff, ctx); + } + break; + + /* function call */ + case BPF_JMP | BPF_CALL: + { + bool fixed; + int ret; + u64 addr; + + mark_call(ctx); + ret = bpf_jit_get_func_addr(ctx->prog, insn, extra_pass, &addr, + &fixed); + if (ret < 0) + return ret; + ret = emit_call(fixed, addr, ctx); + if (ret) + return ret; + break; + } + /* tail call */ + case BPF_JMP | BPF_TAIL_CALL: + if (emit_bpf_tail_call(i, ctx)) + return -1; + break; + + /* function return */ + case BPF_JMP | BPF_EXIT: + if (i == ctx->prog->len - 1) + break; + + rvoff = epilogue_offset(ctx); + emit_jump_and_link(RV_REG_ZERO, rvoff, false, ctx); + break; + + /* dst = imm64 */ + case BPF_LD | BPF_IMM | BPF_DW: + { + struct bpf_insn insn1 = insn[1]; + u64 imm64; + + imm64 = (u64)insn1.imm << 32 | (u32)imm; + emit_imm(rd, imm64, ctx); + return 1; + } + + /* LDX: dst = *(size *)(src + off) */ + case BPF_LDX | BPF_MEM | BPF_B: + if (is_12b_int(off)) { + emit(rv_lbu(rd, off, rs), ctx); + break; + } + + emit_imm(RV_REG_T1, off, ctx); + emit(rv_add(RV_REG_T1, RV_REG_T1, rs), ctx); + emit(rv_lbu(rd, 0, RV_REG_T1), ctx); + if (insn_is_zext(&insn[1])) + return 1; + break; + case BPF_LDX | BPF_MEM | BPF_H: + if (is_12b_int(off)) { + emit(rv_lhu(rd, off, rs), ctx); + break; + } + + emit_imm(RV_REG_T1, off, ctx); + emit(rv_add(RV_REG_T1, RV_REG_T1, rs), ctx); + emit(rv_lhu(rd, 0, RV_REG_T1), ctx); + if (insn_is_zext(&insn[1])) + return 1; + break; + case BPF_LDX | BPF_MEM | BPF_W: + if (is_12b_int(off)) { + emit(rv_lwu(rd, off, rs), ctx); + break; + } + + emit_imm(RV_REG_T1, off, ctx); + emit(rv_add(RV_REG_T1, RV_REG_T1, rs), ctx); + emit(rv_lwu(rd, 0, RV_REG_T1), ctx); + if (insn_is_zext(&insn[1])) + return 1; + break; + case BPF_LDX | BPF_MEM | BPF_DW: + if (is_12b_int(off)) { + emit(rv_ld(rd, off, rs), ctx); + break; + } + + emit_imm(RV_REG_T1, off, ctx); + emit(rv_add(RV_REG_T1, RV_REG_T1, rs), ctx); + emit(rv_ld(rd, 0, RV_REG_T1), ctx); + break; + + /* ST: *(size *)(dst + off) = imm */ + case BPF_ST | BPF_MEM | BPF_B: + emit_imm(RV_REG_T1, imm, ctx); + if (is_12b_int(off)) { + emit(rv_sb(rd, off, RV_REG_T1), ctx); + break; + } + + emit_imm(RV_REG_T2, off, ctx); + emit(rv_add(RV_REG_T2, RV_REG_T2, rd), ctx); + emit(rv_sb(RV_REG_T2, 0, RV_REG_T1), ctx); + break; + + case BPF_ST | BPF_MEM | BPF_H: + emit_imm(RV_REG_T1, imm, ctx); + if (is_12b_int(off)) { + emit(rv_sh(rd, off, RV_REG_T1), ctx); + break; + } + + emit_imm(RV_REG_T2, off, ctx); + emit(rv_add(RV_REG_T2, RV_REG_T2, rd), ctx); + emit(rv_sh(RV_REG_T2, 0, RV_REG_T1), ctx); + break; + case BPF_ST | BPF_MEM | BPF_W: + emit_imm(RV_REG_T1, imm, ctx); + if (is_12b_int(off)) { + emit(rv_sw(rd, off, RV_REG_T1), ctx); + break; + } + + emit_imm(RV_REG_T2, off, ctx); + emit(rv_add(RV_REG_T2, RV_REG_T2, rd), ctx); + emit(rv_sw(RV_REG_T2, 0, RV_REG_T1), ctx); + break; + case BPF_ST | BPF_MEM | BPF_DW: + emit_imm(RV_REG_T1, imm, ctx); + if (is_12b_int(off)) { + emit(rv_sd(rd, off, RV_REG_T1), ctx); + break; + } + + emit_imm(RV_REG_T2, off, ctx); + emit(rv_add(RV_REG_T2, RV_REG_T2, rd), ctx); + emit(rv_sd(RV_REG_T2, 0, RV_REG_T1), ctx); + break; + + /* STX: *(size *)(dst + off) = src */ + case BPF_STX | BPF_MEM | BPF_B: + if (is_12b_int(off)) { + emit(rv_sb(rd, off, rs), ctx); + break; + } + + emit_imm(RV_REG_T1, off, ctx); + emit(rv_add(RV_REG_T1, RV_REG_T1, rd), ctx); + emit(rv_sb(RV_REG_T1, 0, rs), ctx); + break; + case BPF_STX | BPF_MEM | BPF_H: + if (is_12b_int(off)) { + emit(rv_sh(rd, off, rs), ctx); + break; + } + + emit_imm(RV_REG_T1, off, ctx); + emit(rv_add(RV_REG_T1, RV_REG_T1, rd), ctx); + emit(rv_sh(RV_REG_T1, 0, rs), ctx); + break; + case BPF_STX | BPF_MEM | BPF_W: + if (is_12b_int(off)) { + emit(rv_sw(rd, off, rs), ctx); + break; + } + + emit_imm(RV_REG_T1, off, ctx); + emit(rv_add(RV_REG_T1, RV_REG_T1, rd), ctx); + emit(rv_sw(RV_REG_T1, 0, rs), ctx); + break; + case BPF_STX | BPF_MEM | BPF_DW: + if (is_12b_int(off)) { + emit(rv_sd(rd, off, rs), ctx); + break; + } + + emit_imm(RV_REG_T1, off, ctx); + emit(rv_add(RV_REG_T1, RV_REG_T1, rd), ctx); + emit(rv_sd(RV_REG_T1, 0, rs), ctx); + break; + /* STX XADD: lock *(u32 *)(dst + off) += src */ + case BPF_STX | BPF_XADD | BPF_W: + /* STX XADD: lock *(u64 *)(dst + off) += src */ + case BPF_STX | BPF_XADD | BPF_DW: + if (off) { + if (is_12b_int(off)) { + emit(rv_addi(RV_REG_T1, rd, off), ctx); + } else { + emit_imm(RV_REG_T1, off, ctx); + emit(rv_add(RV_REG_T1, RV_REG_T1, rd), ctx); + } + + rd = RV_REG_T1; + } + + emit(BPF_SIZE(code) == BPF_W ? + rv_amoadd_w(RV_REG_ZERO, rs, rd, 0, 0) : + rv_amoadd_d(RV_REG_ZERO, rs, rd, 0, 0), ctx); + break; + default: + pr_err("bpf-jit: unknown opcode %02x\n", code); + return -EINVAL; + } + + return 0; +} + +void bpf_jit_build_prologue(struct rv_jit_context *ctx) +{ + int stack_adjust = 0, store_offset, bpf_stack_adjust; + + bpf_stack_adjust = round_up(ctx->prog->aux->stack_depth, 16); + if (bpf_stack_adjust) + mark_fp(ctx); + + if (seen_reg(RV_REG_RA, ctx)) + stack_adjust += 8; + stack_adjust += 8; /* RV_REG_FP */ + if (seen_reg(RV_REG_S1, ctx)) + stack_adjust += 8; + if (seen_reg(RV_REG_S2, ctx)) + stack_adjust += 8; + if (seen_reg(RV_REG_S3, ctx)) + stack_adjust += 8; + if (seen_reg(RV_REG_S4, ctx)) + stack_adjust += 8; + if (seen_reg(RV_REG_S5, ctx)) + stack_adjust += 8; + if (seen_reg(RV_REG_S6, ctx)) + stack_adjust += 8; + + stack_adjust = round_up(stack_adjust, 16); + stack_adjust += bpf_stack_adjust; + + store_offset = stack_adjust - 8; + + /* First instruction is always setting the tail-call-counter + * (TCC) register. This instruction is skipped for tail calls. + */ + emit(rv_addi(RV_REG_TCC, RV_REG_ZERO, MAX_TAIL_CALL_CNT), ctx); + + emit(rv_addi(RV_REG_SP, RV_REG_SP, -stack_adjust), ctx); + + if (seen_reg(RV_REG_RA, ctx)) { + emit(rv_sd(RV_REG_SP, store_offset, RV_REG_RA), ctx); + store_offset -= 8; + } + emit(rv_sd(RV_REG_SP, store_offset, RV_REG_FP), ctx); + store_offset -= 8; + if (seen_reg(RV_REG_S1, ctx)) { + emit(rv_sd(RV_REG_SP, store_offset, RV_REG_S1), ctx); + store_offset -= 8; + } + if (seen_reg(RV_REG_S2, ctx)) { + emit(rv_sd(RV_REG_SP, store_offset, RV_REG_S2), ctx); + store_offset -= 8; + } + if (seen_reg(RV_REG_S3, ctx)) { + emit(rv_sd(RV_REG_SP, store_offset, RV_REG_S3), ctx); + store_offset -= 8; + } + if (seen_reg(RV_REG_S4, ctx)) { + emit(rv_sd(RV_REG_SP, store_offset, RV_REG_S4), ctx); + store_offset -= 8; + } + if (seen_reg(RV_REG_S5, ctx)) { + emit(rv_sd(RV_REG_SP, store_offset, RV_REG_S5), ctx); + store_offset -= 8; + } + if (seen_reg(RV_REG_S6, ctx)) { + emit(rv_sd(RV_REG_SP, store_offset, RV_REG_S6), ctx); + store_offset -= 8; + } + + emit(rv_addi(RV_REG_FP, RV_REG_SP, stack_adjust), ctx); + + if (bpf_stack_adjust) + emit(rv_addi(RV_REG_S5, RV_REG_SP, bpf_stack_adjust), ctx); + + /* Program contains calls and tail calls, so RV_REG_TCC need + * to be saved across calls. + */ + if (seen_tail_call(ctx) && seen_call(ctx)) + emit(rv_addi(RV_REG_TCC_SAVED, RV_REG_TCC, 0), ctx); + + ctx->stack_size = stack_adjust; +} + +void bpf_jit_build_epilogue(struct rv_jit_context *ctx) +{ + __build_epilogue(false, ctx); +} + +void *bpf_jit_alloc_exec(unsigned long size) +{ + return __vmalloc_node_range(size, PAGE_SIZE, BPF_JIT_REGION_START, + BPF_JIT_REGION_END, GFP_KERNEL, + PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE, + __builtin_return_address(0)); +} + +void bpf_jit_free_exec(void *addr) +{ + return vfree(addr); +} |