diff options
Diffstat (limited to 'arch/powerpc/net/bpf_jit_comp32.c')
| -rw-r--r-- | arch/powerpc/net/bpf_jit_comp32.c | 179 |
1 files changed, 133 insertions, 46 deletions
diff --git a/arch/powerpc/net/bpf_jit_comp32.c b/arch/powerpc/net/bpf_jit_comp32.c index 7f91ea064c08..3087e744fb25 100644 --- a/arch/powerpc/net/bpf_jit_comp32.c +++ b/arch/powerpc/net/bpf_jit_comp32.c @@ -127,13 +127,16 @@ void bpf_jit_build_prologue(u32 *image, struct codegen_context *ctx) { int i; + /* Instruction for trampoline attach */ + EMIT(PPC_RAW_NOP()); + /* Initialize tail_call_cnt, to be skipped if we do tail calls. */ if (ctx->seen & SEEN_TAILCALL) EMIT(PPC_RAW_LI(_R4, 0)); else EMIT(PPC_RAW_NOP()); -#define BPF_TAILCALL_PROLOGUE_SIZE 4 +#define BPF_TAILCALL_PROLOGUE_SIZE 8 if (bpf_has_stack_frame(ctx)) EMIT(PPC_RAW_STWU(_R1, _R1, -BPF_PPC_STACKFRAME(ctx))); @@ -198,14 +201,17 @@ void bpf_jit_build_epilogue(u32 *image, struct codegen_context *ctx) bpf_jit_emit_common_epilogue(image, ctx); EMIT(PPC_RAW_BLR()); + + bpf_jit_build_fentry_stubs(image, ctx); } -int bpf_jit_emit_func_call_rel(u32 *image, struct codegen_context *ctx, u64 func) +/* Relative offset needs to be calculated based on final image location */ +int bpf_jit_emit_func_call_rel(u32 *image, u32 *fimage, struct codegen_context *ctx, u64 func) { - s32 rel = (s32)func - (s32)(image + ctx->idx); + s32 rel = (s32)func - (s32)(fimage + ctx->idx); if (image && rel < 0x2000000 && rel >= -0x2000000) { - PPC_BL(func); + EMIT(PPC_RAW_BL(rel)); } else { /* Load function address into r0 */ EMIT(PPC_RAW_LIS(_R0, IMM_H(func))); @@ -278,7 +284,7 @@ static int bpf_jit_emit_tail_call(u32 *image, struct codegen_context *ctx, u32 o } /* Assemble the body code between the prologue & epilogue */ -int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context *ctx, +int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, u32 *fimage, struct codegen_context *ctx, u32 *addrs, int pass, bool extra_pass) { const struct bpf_insn *insn = fp->insnsi; @@ -307,7 +313,6 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context * u64 func_addr; u32 true_cond; u32 tmp_idx; - int j; if (i && (BPF_CLASS(code) == BPF_ALU64 || BPF_CLASS(code) == BPF_ALU) && (BPF_CLASS(prevcode) == BPF_ALU64 || BPF_CLASS(prevcode) == BPF_ALU) && @@ -449,10 +454,16 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context * } break; case BPF_ALU | BPF_DIV | BPF_X: /* (u32) dst /= (u32) src */ - EMIT(PPC_RAW_DIVWU(dst_reg, src2_reg, src_reg)); + if (off) + EMIT(PPC_RAW_DIVW(dst_reg, src2_reg, src_reg)); + else + EMIT(PPC_RAW_DIVWU(dst_reg, src2_reg, src_reg)); break; case BPF_ALU | BPF_MOD | BPF_X: /* (u32) dst %= (u32) src */ - EMIT(PPC_RAW_DIVWU(_R0, src2_reg, src_reg)); + if (off) + EMIT(PPC_RAW_DIVW(_R0, src2_reg, src_reg)); + else + EMIT(PPC_RAW_DIVWU(_R0, src2_reg, src_reg)); EMIT(PPC_RAW_MULW(_R0, src_reg, _R0)); EMIT(PPC_RAW_SUB(dst_reg, src2_reg, _R0)); break; @@ -466,10 +477,16 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context * if (imm == 1) { EMIT(PPC_RAW_MR(dst_reg, src2_reg)); } else if (is_power_of_2((u32)imm)) { - EMIT(PPC_RAW_SRWI(dst_reg, src2_reg, ilog2(imm))); + if (off) + EMIT(PPC_RAW_SRAWI(dst_reg, src2_reg, ilog2(imm))); + else + EMIT(PPC_RAW_SRWI(dst_reg, src2_reg, ilog2(imm))); } else { PPC_LI32(_R0, imm); - EMIT(PPC_RAW_DIVWU(dst_reg, src2_reg, _R0)); + if (off) + EMIT(PPC_RAW_DIVW(dst_reg, src2_reg, _R0)); + else + EMIT(PPC_RAW_DIVWU(dst_reg, src2_reg, _R0)); } break; case BPF_ALU | BPF_MOD | BPF_K: /* (u32) dst %= (u32) imm */ @@ -479,11 +496,19 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context * if (!is_power_of_2((u32)imm)) { bpf_set_seen_register(ctx, tmp_reg); PPC_LI32(tmp_reg, imm); - EMIT(PPC_RAW_DIVWU(_R0, src2_reg, tmp_reg)); + if (off) + EMIT(PPC_RAW_DIVW(_R0, src2_reg, tmp_reg)); + else + EMIT(PPC_RAW_DIVWU(_R0, src2_reg, tmp_reg)); EMIT(PPC_RAW_MULW(_R0, tmp_reg, _R0)); EMIT(PPC_RAW_SUB(dst_reg, src2_reg, _R0)); } else if (imm == 1) { EMIT(PPC_RAW_LI(dst_reg, 0)); + } else if (off) { + EMIT(PPC_RAW_SRAWI(_R0, src2_reg, ilog2(imm))); + EMIT(PPC_RAW_ADDZE(_R0, _R0)); + EMIT(PPC_RAW_SLWI(_R0, _R0, ilog2(imm))); + EMIT(PPC_RAW_SUB(dst_reg, src2_reg, _R0)); } else { imm = ilog2((u32)imm); EMIT(PPC_RAW_RLWINM(dst_reg, src2_reg, 0, 32 - imm, 31)); @@ -496,11 +521,21 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context * imm = -imm; if (!is_power_of_2(imm)) return -EOPNOTSUPP; - if (imm == 1) + if (imm == 1) { EMIT(PPC_RAW_LI(dst_reg, 0)); - else + EMIT(PPC_RAW_LI(dst_reg_h, 0)); + } else if (off) { + EMIT(PPC_RAW_SRAWI(dst_reg_h, src2_reg_h, 31)); + EMIT(PPC_RAW_XOR(dst_reg, src2_reg, dst_reg_h)); + EMIT(PPC_RAW_SUBFC(dst_reg, dst_reg_h, dst_reg)); + EMIT(PPC_RAW_RLWINM(dst_reg, dst_reg, 0, 32 - ilog2(imm), 31)); + EMIT(PPC_RAW_XOR(dst_reg, dst_reg, dst_reg_h)); + EMIT(PPC_RAW_SUBFC(dst_reg, dst_reg_h, dst_reg)); + EMIT(PPC_RAW_SUBFE(dst_reg_h, dst_reg_h, dst_reg_h)); + } else { EMIT(PPC_RAW_RLWINM(dst_reg, src2_reg, 0, 32 - ilog2(imm), 31)); - EMIT(PPC_RAW_LI(dst_reg_h, 0)); + EMIT(PPC_RAW_LI(dst_reg_h, 0)); + } break; case BPF_ALU64 | BPF_DIV | BPF_K: /* dst /= imm */ if (!imm) @@ -726,15 +761,30 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context * * MOV */ case BPF_ALU64 | BPF_MOV | BPF_X: /* dst = src */ - if (dst_reg == src_reg) - break; - EMIT(PPC_RAW_MR(dst_reg, src_reg)); - EMIT(PPC_RAW_MR(dst_reg_h, src_reg_h)); + if (off == 8) { + EMIT(PPC_RAW_EXTSB(dst_reg, src_reg)); + EMIT(PPC_RAW_SRAWI(dst_reg_h, dst_reg, 31)); + } else if (off == 16) { + EMIT(PPC_RAW_EXTSH(dst_reg, src_reg)); + EMIT(PPC_RAW_SRAWI(dst_reg_h, dst_reg, 31)); + } else if (off == 32 && dst_reg == src_reg) { + EMIT(PPC_RAW_SRAWI(dst_reg_h, src_reg, 31)); + } else if (off == 32) { + EMIT(PPC_RAW_MR(dst_reg, src_reg)); + EMIT(PPC_RAW_SRAWI(dst_reg_h, src_reg, 31)); + } else if (dst_reg != src_reg) { + EMIT(PPC_RAW_MR(dst_reg, src_reg)); + EMIT(PPC_RAW_MR(dst_reg_h, src_reg_h)); + } break; case BPF_ALU | BPF_MOV | BPF_X: /* (u32) dst = src */ /* special mov32 for zext */ if (imm == 1) EMIT(PPC_RAW_LI(dst_reg_h, 0)); + else if (off == 8) + EMIT(PPC_RAW_EXTSB(dst_reg, src_reg)); + else if (off == 16) + EMIT(PPC_RAW_EXTSH(dst_reg, src_reg)); else if (dst_reg != src_reg) EMIT(PPC_RAW_MR(dst_reg, src_reg)); break; @@ -750,6 +800,7 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context * * BPF_FROM_BE/LE */ case BPF_ALU | BPF_END | BPF_FROM_LE: + case BPF_ALU64 | BPF_END | BPF_FROM_LE: switch (imm) { case 16: /* Copy 16 bits to upper part */ @@ -784,6 +835,8 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context * EMIT(PPC_RAW_MR(dst_reg_h, tmp_reg)); break; } + if (BPF_CLASS(code) == BPF_ALU64 && imm != 64) + EMIT(PPC_RAW_LI(dst_reg_h, 0)); break; case BPF_ALU | BPF_END | BPF_FROM_BE: switch (imm) { @@ -851,6 +904,15 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context * /* Get offset into TMP_REG */ EMIT(PPC_RAW_LI(tmp_reg, off)); + /* + * Enforce full ordering for operations with BPF_FETCH by emitting a 'sync' + * before and after the operation. + * + * This is a requirement in the Linux Kernel Memory Model. + * See __cmpxchg_u32() in asm/cmpxchg.h as an example. + */ + if ((imm & BPF_FETCH) && IS_ENABLED(CONFIG_SMP)) + EMIT(PPC_RAW_SYNC()); tmp_idx = ctx->idx * 4; /* load value from memory into r0 */ EMIT(PPC_RAW_LWARX(_R0, tmp_reg, dst_reg, 0)); @@ -904,6 +966,9 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context * /* For the BPF_FETCH variant, get old data into src_reg */ if (imm & BPF_FETCH) { + /* Emit 'sync' to enforce full ordering */ + if (IS_ENABLED(CONFIG_SMP)) + EMIT(PPC_RAW_SYNC()); EMIT(PPC_RAW_MR(ret_reg, ax_reg)); if (!fp->aux->verifier_zext) EMIT(PPC_RAW_LI(ret_reg - 1, 0)); /* higher 32-bit */ @@ -917,11 +982,17 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context * * BPF_LDX */ case BPF_LDX | BPF_MEM | BPF_B: /* dst = *(u8 *)(ul) (src + off) */ + case BPF_LDX | BPF_MEMSX | BPF_B: case BPF_LDX | BPF_PROBE_MEM | BPF_B: + case BPF_LDX | BPF_PROBE_MEMSX | BPF_B: case BPF_LDX | BPF_MEM | BPF_H: /* dst = *(u16 *)(ul) (src + off) */ + case BPF_LDX | BPF_MEMSX | BPF_H: case BPF_LDX | BPF_PROBE_MEM | BPF_H: + case BPF_LDX | BPF_PROBE_MEMSX | BPF_H: case BPF_LDX | BPF_MEM | BPF_W: /* dst = *(u32 *)(ul) (src + off) */ + case BPF_LDX | BPF_MEMSX | BPF_W: case BPF_LDX | BPF_PROBE_MEM | BPF_W: + case BPF_LDX | BPF_PROBE_MEMSX | BPF_W: case BPF_LDX | BPF_MEM | BPF_DW: /* dst = *(u64 *)(ul) (src + off) */ case BPF_LDX | BPF_PROBE_MEM | BPF_DW: /* @@ -930,7 +1001,7 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context * * load only if addr is kernel address (see is_kernel_addr()), otherwise * set dst_reg=0 and move on. */ - if (BPF_MODE(code) == BPF_PROBE_MEM) { + if (BPF_MODE(code) == BPF_PROBE_MEM || BPF_MODE(code) == BPF_PROBE_MEMSX) { PPC_LI32(_R0, TASK_SIZE - off); EMIT(PPC_RAW_CMPLW(src_reg, _R0)); PPC_BCC_SHORT(COND_GT, (ctx->idx + 4) * 4); @@ -940,7 +1011,7 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context * * !fp->aux->verifier_zext. Emit NOP otherwise. * * Note that "li reg_h,0" is emitted for BPF_B/H/W case, - * if necessary. So, jump there insted of emitting an + * if necessary. So, jump there instead of emitting an * additional "li reg_h,0" instruction. */ if (size == BPF_DW && !fp->aux->verifier_zext) @@ -952,30 +1023,48 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context * * as there are two load instructions for dst_reg_h & dst_reg * respectively. */ - if (size == BPF_DW) + if (size == BPF_DW || + (size == BPF_B && BPF_MODE(code) == BPF_PROBE_MEMSX)) PPC_JMP((ctx->idx + 3) * 4); else PPC_JMP((ctx->idx + 2) * 4); } - switch (size) { - case BPF_B: - EMIT(PPC_RAW_LBZ(dst_reg, src_reg, off)); - break; - case BPF_H: - EMIT(PPC_RAW_LHZ(dst_reg, src_reg, off)); - break; - case BPF_W: - EMIT(PPC_RAW_LWZ(dst_reg, src_reg, off)); - break; - case BPF_DW: - EMIT(PPC_RAW_LWZ(dst_reg_h, src_reg, off)); - EMIT(PPC_RAW_LWZ(dst_reg, src_reg, off + 4)); - break; - } + if (BPF_MODE(code) == BPF_MEMSX || BPF_MODE(code) == BPF_PROBE_MEMSX) { + switch (size) { + case BPF_B: + EMIT(PPC_RAW_LBZ(dst_reg, src_reg, off)); + EMIT(PPC_RAW_EXTSB(dst_reg, dst_reg)); + break; + case BPF_H: + EMIT(PPC_RAW_LHA(dst_reg, src_reg, off)); + break; + case BPF_W: + EMIT(PPC_RAW_LWZ(dst_reg, src_reg, off)); + break; + } + if (!fp->aux->verifier_zext) + EMIT(PPC_RAW_SRAWI(dst_reg_h, dst_reg, 31)); - if (size != BPF_DW && !fp->aux->verifier_zext) - EMIT(PPC_RAW_LI(dst_reg_h, 0)); + } else { + switch (size) { + case BPF_B: + EMIT(PPC_RAW_LBZ(dst_reg, src_reg, off)); + break; + case BPF_H: + EMIT(PPC_RAW_LHZ(dst_reg, src_reg, off)); + break; + case BPF_W: + EMIT(PPC_RAW_LWZ(dst_reg, src_reg, off)); + break; + case BPF_DW: + EMIT(PPC_RAW_LWZ(dst_reg_h, src_reg, off)); + EMIT(PPC_RAW_LWZ(dst_reg, src_reg, off + 4)); + break; + } + if (size != BPF_DW && !fp->aux->verifier_zext) + EMIT(PPC_RAW_LI(dst_reg_h, 0)); + } if (BPF_MODE(code) == BPF_PROBE_MEM) { int insn_idx = ctx->idx - 1; @@ -997,8 +1086,8 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context * jmp_off += 4; } - ret = bpf_add_extable_entry(fp, image, pass, ctx, insn_idx, - jmp_off, dst_reg); + ret = bpf_add_extable_entry(fp, image, fimage, pass, ctx, insn_idx, + jmp_off, dst_reg, code); if (ret) return ret; } @@ -1009,13 +1098,8 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context * * 16 byte instruction that uses two 'struct bpf_insn' */ case BPF_LD | BPF_IMM | BPF_DW: /* dst = (u64) imm */ - tmp_idx = ctx->idx; PPC_LI32(dst_reg_h, (u32)insn[i + 1].imm); PPC_LI32(dst_reg, (u32)insn[i].imm); - /* padding to allow full 4 instructions for later patching */ - if (!image) - for (j = ctx->idx - tmp_idx; j < 4; j++) - EMIT(PPC_RAW_NOP()); /* Adjust for two bpf instructions */ addrs[++i] = ctx->idx * 4; break; @@ -1053,7 +1137,7 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context * EMIT(PPC_RAW_STW(bpf_to_ppc(BPF_REG_5), _R1, 12)); } - ret = bpf_jit_emit_func_call_rel(image, ctx, func_addr); + ret = bpf_jit_emit_func_call_rel(image, fimage, ctx, func_addr); if (ret) return ret; @@ -1067,6 +1151,9 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context * case BPF_JMP | BPF_JA: PPC_JMP(addrs[i + 1 + off]); break; + case BPF_JMP32 | BPF_JA: + PPC_JMP(addrs[i + 1 + imm]); + break; case BPF_JMP | BPF_JGT | BPF_K: case BPF_JMP | BPF_JGT | BPF_X: |
