arch/powerpc/net/bpf_jit_comp64.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * bpf_jit_comp64.c: eBPF JIT compiler
   4  *
   5  * Copyright 2016 Naveen N. Rao <[email protected]>
   6  *                IBM Corporation
   7  *
   8  * Based on the powerpc classic BPF JIT compiler by Matt Evans
   9  */
  10 #include <linux/moduleloader.h>
  11 #include <asm/cacheflush.h>
  12 #include <asm/asm-compat.h>
  13 #include <linux/netdevice.h>
  14 #include <linux/filter.h>
  15 #include <linux/if_vlan.h>
  16 #include <asm/kprobes.h>
  17 #include <linux/bpf.h>
  18 #include <asm/security_features.h>
  19
  20 #include "bpf_jit64.h"
  21
  22 static inline bool bpf_has_stack_frame(struct codegen_context *ctx)
  23 {
  24         /*
  25          * We only need a stack frame if:
  26          * - we call other functions (kernel helpers), or
  27          * - the bpf program uses its stack area
  28          * The latter condition is deduced from the usage of BPF_REG_FP
  29          */
  30         return ctx->seen & SEEN_FUNC || bpf_is_seen_register(ctx, b2p[BPF_REG_FP]);
  31 }
  32
  33 /*
  34  * When not setting up our own stackframe, the redzone usage is:
  35  *
  36  *              [       prev sp         ] <-------------
  37  *              [         ...           ]               |
  38  * sp (r1) ---> [    stack pointer      ] --------------
  39  *              [   nv gpr save area    ] 5*8
  40  *              [    tail_call_cnt      ] 8
  41  *              [    local_tmp_var      ] 16
  42  *              [   unused red zone     ] 208 bytes protected
  43  */
  44 static int bpf_jit_stack_local(struct codegen_context *ctx)
  45 {
  46         if (bpf_has_stack_frame(ctx))
  47                 return STACK_FRAME_MIN_SIZE + ctx->stack_size;
  48         else
  49                 return -(BPF_PPC_STACK_SAVE + 24);
  50 }
  51
  52 static int bpf_jit_stack_tailcallcnt(struct codegen_context *ctx)
  53 {
  54         return bpf_jit_stack_local(ctx) + 16;
  55 }
  56
  57 static int bpf_jit_stack_offsetof(struct codegen_context *ctx, int reg)
  58 {
  59         if (reg >= BPF_PPC_NVR_MIN && reg < 32)
  60                 return (bpf_has_stack_frame(ctx) ?
  61                         (BPF_PPC_STACKFRAME + ctx->stack_size) : 0)
  62                                 - (8 * (32 - reg));
  63
  64         pr_err("BPF JIT is asking about unknown registers");
  65         BUG();
  66 }
  67
  68 void bpf_jit_realloc_regs(struct codegen_context *ctx)
  69 {
  70 }
  71
  72 void bpf_jit_build_prologue(u32 *image, struct codegen_context *ctx)
  73 {
  74         int i;
  75
  76         /*
  77          * Initialize tail_call_cnt if we do tail calls.
  78          * Otherwise, put in NOPs so that it can be skipped when we are
  79          * invoked through a tail call.
  80          */
  81         if (ctx->seen & SEEN_TAILCALL) {
  82                 EMIT(PPC_RAW_LI(b2p[TMP_REG_1], 0));
  83                 /* this goes in the redzone */
  84                 PPC_BPF_STL(b2p[TMP_REG_1], 1, -(BPF_PPC_STACK_SAVE + 8));
  85         } else {
  86                 EMIT(PPC_RAW_NOP());
  87                 EMIT(PPC_RAW_NOP());
  88         }
  89
  90 #define BPF_TAILCALL_PROLOGUE_SIZE      8
  91
  92         if (bpf_has_stack_frame(ctx)) {
  93                 /*
  94                  * We need a stack frame, but we don't necessarily need to
  95                  * save/restore LR unless we call other functions
  96                  */
  97                 if (ctx->seen & SEEN_FUNC) {
  98                         EMIT(PPC_RAW_MFLR(_R0));
  99                         PPC_BPF_STL(0, 1, PPC_LR_STKOFF);
 100                 }
 101
 102                 PPC_BPF_STLU(1, 1, -(BPF_PPC_STACKFRAME + ctx->stack_size));
 103         }
 104
 105         /*
 106          * Back up non-volatile regs -- BPF registers 6-10
 107          * If we haven't created our own stack frame, we save these
 108          * in the protected zone below the previous stack frame
 109          */
 110         for (i = BPF_REG_6; i <= BPF_REG_10; i++)
 111                 if (bpf_is_seen_register(ctx, b2p[i]))
 112                         PPC_BPF_STL(b2p[i], 1, bpf_jit_stack_offsetof(ctx, b2p[i]));
 113
 114         /* Setup frame pointer to point to the bpf stack area */
 115         if (bpf_is_seen_register(ctx, b2p[BPF_REG_FP]))
 116                 EMIT(PPC_RAW_ADDI(b2p[BPF_REG_FP], 1,
 117                                 STACK_FRAME_MIN_SIZE + ctx->stack_size));
 118 }
 119
 120 static void bpf_jit_emit_common_epilogue(u32 *image, struct codegen_context *ctx)
 121 {
 122         int i;
 123
 124         /* Restore NVRs */
 125         for (i = BPF_REG_6; i <= BPF_REG_10; i++)
 126                 if (bpf_is_seen_register(ctx, b2p[i]))
 127                         PPC_BPF_LL(b2p[i], 1, bpf_jit_stack_offsetof(ctx, b2p[i]));
 128
 129         /* Tear down our stack frame */
 130         if (bpf_has_stack_frame(ctx)) {
 131                 EMIT(PPC_RAW_ADDI(1, 1, BPF_PPC_STACKFRAME + ctx->stack_size));
 132                 if (ctx->seen & SEEN_FUNC) {
 133                         PPC_BPF_LL(0, 1, PPC_LR_STKOFF);
 134                         EMIT(PPC_RAW_MTLR(0));
 135                 }
 136         }
 137 }
 138
 139 void bpf_jit_build_epilogue(u32 *image, struct codegen_context *ctx)
 140 {
 141         bpf_jit_emit_common_epilogue(image, ctx);
 142
 143         /* Move result to r3 */
 144         EMIT(PPC_RAW_MR(3, b2p[BPF_REG_0]));
 145
 146         EMIT(PPC_RAW_BLR());
 147 }
 148
 149 static void bpf_jit_emit_func_call_hlp(u32 *image, struct codegen_context *ctx,
 150                                        u64 func)
 151 {
 152 #ifdef PPC64_ELF_ABI_v1
 153         /* func points to the function descriptor */
 154         PPC_LI64(b2p[TMP_REG_2], func);
 155         /* Load actual entry point from function descriptor */
 156         PPC_BPF_LL(b2p[TMP_REG_1], b2p[TMP_REG_2], 0);
 157         /* ... and move it to CTR */
 158         EMIT(PPC_RAW_MTCTR(b2p[TMP_REG_1]));
 159         /*
 160          * Load TOC from function descriptor at offset 8.
 161          * We can clobber r2 since we get called through a
 162          * function pointer (so caller will save/restore r2)
 163          * and since we don't use a TOC ourself.
 164          */
 165         PPC_BPF_LL(2, b2p[TMP_REG_2], 8);
 166 #else
 167         /* We can clobber r12 */
 168         PPC_FUNC_ADDR(12, func);
 169         EMIT(PPC_RAW_MTCTR(12));
 170 #endif
 171         EMIT(PPC_RAW_BCTRL());
 172 }
 173
 174 void bpf_jit_emit_func_call_rel(u32 *image, struct codegen_context *ctx, u64 func)
 175 {
 176         unsigned int i, ctx_idx = ctx->idx;
 177
 178         /* Load function address into r12 */
 179         PPC_LI64(12, func);
 180
 181         /* For bpf-to-bpf function calls, the callee's address is unknown
 182          * until the last extra pass. As seen above, we use PPC_LI64() to
 183          * load the callee's address, but this may optimize the number of
 184          * instructions required based on the nature of the address.
 185          *
 186          * Since we don't want the number of instructions emitted to change,
 187          * we pad the optimized PPC_LI64() call with NOPs to guarantee that
 188          * we always have a five-instruction sequence, which is the maximum
 189          * that PPC_LI64() can emit.
 190          */
 191         for (i = ctx->idx - ctx_idx; i < 5; i++)
 192                 EMIT(PPC_RAW_NOP());
 193
 194 #ifdef PPC64_ELF_ABI_v1
 195         /*
 196          * Load TOC from function descriptor at offset 8.
 197          * We can clobber r2 since we get called through a
 198          * function pointer (so caller will save/restore r2)
 199          * and since we don't use a TOC ourself.
 200          */
 201         PPC_BPF_LL(2, 12, 8);
 202         /* Load actual entry point from function descriptor */
 203         PPC_BPF_LL(12, 12, 0);
 204 #endif
 205
 206         EMIT(PPC_RAW_MTCTR(12));
 207         EMIT(PPC_RAW_BCTRL());
 208 }
 209
 210 static int bpf_jit_emit_tail_call(u32 *image, struct codegen_context *ctx, u32 out)
 211 {
 212         /*
 213          * By now, the eBPF program has already setup parameters in r3, r4 and r5
 214          * r3/BPF_REG_1 - pointer to ctx -- passed as is to the next bpf program
 215          * r4/BPF_REG_2 - pointer to bpf_array
 216          * r5/BPF_REG_3 - index in bpf_array
 217          */
 218         int b2p_bpf_array = b2p[BPF_REG_2];
 219         int b2p_index = b2p[BPF_REG_3];
 220
 221         /*
 222          * if (index >= array->map.max_entries)
 223          *   goto out;
 224          */
 225         EMIT(PPC_RAW_LWZ(b2p[TMP_REG_1], b2p_bpf_array, offsetof(struct bpf_array, map.max_entries)));
 226         EMIT(PPC_RAW_RLWINM(b2p_index, b2p_index, 0, 0, 31));
 227         EMIT(PPC_RAW_CMPLW(b2p_index, b2p[TMP_REG_1]));
 228         PPC_BCC(COND_GE, out);
 229
 230         /*
 231          * if (tail_call_cnt > MAX_TAIL_CALL_CNT)
 232          *   goto out;
 233          */
 234         PPC_BPF_LL(b2p[TMP_REG_1], 1, bpf_jit_stack_tailcallcnt(ctx));
 235         EMIT(PPC_RAW_CMPLWI(b2p[TMP_REG_1], MAX_TAIL_CALL_CNT));
 236         PPC_BCC(COND_GT, out);
 237
 238         /*
 239          * tail_call_cnt++;
 240          */
 241         EMIT(PPC_RAW_ADDI(b2p[TMP_REG_1], b2p[TMP_REG_1], 1));
 242         PPC_BPF_STL(b2p[TMP_REG_1], 1, bpf_jit_stack_tailcallcnt(ctx));
 243
 244         /* prog = array->ptrs[index]; */
 245         EMIT(PPC_RAW_MULI(b2p[TMP_REG_1], b2p_index, 8));
 246         EMIT(PPC_RAW_ADD(b2p[TMP_REG_1], b2p[TMP_REG_1], b2p_bpf_array));
 247         PPC_BPF_LL(b2p[TMP_REG_1], b2p[TMP_REG_1], offsetof(struct bpf_array, ptrs));
 248
 249         /*
 250          * if (prog == NULL)
 251          *   goto out;
 252          */
 253         EMIT(PPC_RAW_CMPLDI(b2p[TMP_REG_1], 0));
 254         PPC_BCC(COND_EQ, out);
 255
 256         /* goto *(prog->bpf_func + prologue_size); */
 257         PPC_BPF_LL(b2p[TMP_REG_1], b2p[TMP_REG_1], offsetof(struct bpf_prog, bpf_func));
 258 #ifdef PPC64_ELF_ABI_v1
 259         /* skip past the function descriptor */
 260         EMIT(PPC_RAW_ADDI(b2p[TMP_REG_1], b2p[TMP_REG_1],
 261                         FUNCTION_DESCR_SIZE + BPF_TAILCALL_PROLOGUE_SIZE));
 262 #else
 263         EMIT(PPC_RAW_ADDI(b2p[TMP_REG_1], b2p[TMP_REG_1], BPF_TAILCALL_PROLOGUE_SIZE));
 264 #endif
 265         EMIT(PPC_RAW_MTCTR(b2p[TMP_REG_1]));
 266
 267         /* tear down stack, restore NVRs, ... */
 268         bpf_jit_emit_common_epilogue(image, ctx);
 269
 270         EMIT(PPC_RAW_BCTR());
 271
 272         /* out: */
 273         return 0;
 274 }
 275
 276 /*
 277  * We spill into the redzone always, even if the bpf program has its own stackframe.
 278  * Offsets hardcoded based on BPF_PPC_STACK_SAVE -- see bpf_jit_stack_local()
 279  */
 280 void bpf_stf_barrier(void);
 281
 282 asm (
 283 "               .global bpf_stf_barrier         ;"
 284 "       bpf_stf_barrier:                        ;"
 285 "               std     21,-64(1)               ;"
 286 "               std     22,-56(1)               ;"
 287 "               sync                            ;"
 288 "               ld      21,-64(1)               ;"
 289 "               ld      22,-56(1)               ;"
 290 "               ori     31,31,0                 ;"
 291 "               .rept 14                        ;"
 292 "               b       1f                      ;"
 293 "       1:                                      ;"
 294 "               .endr                           ;"
 295 "               blr                             ;"
 296 );
 297
 298 /* Assemble the body code between the prologue & epilogue */
 299 int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context *ctx,
 300                        u32 *addrs, bool extra_pass)
 301 {
 302         enum stf_barrier_type stf_barrier = stf_barrier_type_get();
 303         const struct bpf_insn *insn = fp->insnsi;
 304         int flen = fp->len;
 305         int i, ret;
 306
 307         /* Start of epilogue code - will only be valid 2nd pass onwards */
 308         u32 exit_addr = addrs[flen];
 309
 310         for (i = 0; i < flen; i++) {
 311                 u32 code = insn[i].code;
 312                 u32 dst_reg = b2p[insn[i].dst_reg];
 313                 u32 src_reg = b2p[insn[i].src_reg];
 314                 s16 off = insn[i].off;
 315                 s32 imm = insn[i].imm;
 316                 bool func_addr_fixed;
 317                 u64 func_addr;
 318                 u64 imm64;
 319                 u32 true_cond;
 320                 u32 tmp_idx;
 321
 322                 /*
 323                  * addrs[] maps a BPF bytecode address into a real offset from
 324                  * the start of the body code.
 325                  */
 326                 addrs[i] = ctx->idx * 4;
 327
 328                 /*
 329                  * As an optimization, we note down which non-volatile registers
 330                  * are used so that we can only save/restore those in our
 331                  * prologue and epilogue. We do this here regardless of whether
 332                  * the actual BPF instruction uses src/dst registers or not
 333                  * (for instance, BPF_CALL does not use them). The expectation
 334                  * is that those instructions will have src_reg/dst_reg set to
 335                  * 0. Even otherwise, we just lose some prologue/epilogue
 336                  * optimization but everything else should work without
 337                  * any issues.
 338                  */
 339                 if (dst_reg >= BPF_PPC_NVR_MIN && dst_reg < 32)
 340                         bpf_set_seen_register(ctx, dst_reg);
 341                 if (src_reg >= BPF_PPC_NVR_MIN && src_reg < 32)
 342                         bpf_set_seen_register(ctx, src_reg);
 343
 344                 switch (code) {
 345                 /*
 346                  * Arithmetic operations: ADD/SUB/MUL/DIV/MOD/NEG
 347                  */
 348                 case BPF_ALU | BPF_ADD | BPF_X: /* (u32) dst += (u32) src */
 349                 case BPF_ALU64 | BPF_ADD | BPF_X: /* dst += src */
 350                         EMIT(PPC_RAW_ADD(dst_reg, dst_reg, src_reg));
 351                         goto bpf_alu32_trunc;
 352                 case BPF_ALU | BPF_SUB | BPF_X: /* (u32) dst -= (u32) src */
 353                 case BPF_ALU64 | BPF_SUB | BPF_X: /* dst -= src */
 354                         EMIT(PPC_RAW_SUB(dst_reg, dst_reg, src_reg));
 355                         goto bpf_alu32_trunc;
 356                 case BPF_ALU | BPF_ADD | BPF_K: /* (u32) dst += (u32) imm */
 357                 case BPF_ALU64 | BPF_ADD | BPF_K: /* dst += imm */
 358                         if (!imm) {
 359                                 goto bpf_alu32_trunc;
 360                         } else if (imm >= -32768 && imm < 32768) {
 361                                 EMIT(PPC_RAW_ADDI(dst_reg, dst_reg, IMM_L(imm)));
 362                         } else {
 363                                 PPC_LI32(b2p[TMP_REG_1], imm);
 364                                 EMIT(PPC_RAW_ADD(dst_reg, dst_reg, b2p[TMP_REG_1]));
 365                         }
 366                         goto bpf_alu32_trunc;
 367                 case BPF_ALU | BPF_SUB | BPF_K: /* (u32) dst -= (u32) imm */
 368                 case BPF_ALU64 | BPF_SUB | BPF_K: /* dst -= imm */
 369                         if (!imm) {
 370                                 goto bpf_alu32_trunc;
 371                         } else if (imm > -32768 && imm <= 32768) {
 372                                 EMIT(PPC_RAW_ADDI(dst_reg, dst_reg, IMM_L(-imm)));
 373                         } else {
 374                                 PPC_LI32(b2p[TMP_REG_1], imm);
 375                                 EMIT(PPC_RAW_SUB(dst_reg, dst_reg, b2p[TMP_REG_1]));
 376                         }
 377                         goto bpf_alu32_trunc;
 378                 case BPF_ALU | BPF_MUL | BPF_X: /* (u32) dst *= (u32) src */
 379                 case BPF_ALU64 | BPF_MUL | BPF_X: /* dst *= src */
 380                         if (BPF_CLASS(code) == BPF_ALU)
 381                                 EMIT(PPC_RAW_MULW(dst_reg, dst_reg, src_reg));
 382                         else
 383                                 EMIT(PPC_RAW_MULD(dst_reg, dst_reg, src_reg));
 384                         goto bpf_alu32_trunc;
 385                 case BPF_ALU | BPF_MUL | BPF_K: /* (u32) dst *= (u32) imm */
 386                 case BPF_ALU64 | BPF_MUL | BPF_K: /* dst *= imm */
 387                         if (imm >= -32768 && imm < 32768)
 388                                 EMIT(PPC_RAW_MULI(dst_reg, dst_reg, IMM_L(imm)));
 389                         else {
 390                                 PPC_LI32(b2p[TMP_REG_1], imm);
 391                                 if (BPF_CLASS(code) == BPF_ALU)
 392                                         EMIT(PPC_RAW_MULW(dst_reg, dst_reg,
 393                                                         b2p[TMP_REG_1]));
 394                                 else
 395                                         EMIT(PPC_RAW_MULD(dst_reg, dst_reg,
 396                                                         b2p[TMP_REG_1]));
 397                         }
 398                         goto bpf_alu32_trunc;
 399                 case BPF_ALU | BPF_DIV | BPF_X: /* (u32) dst /= (u32) src */
 400                 case BPF_ALU | BPF_MOD | BPF_X: /* (u32) dst %= (u32) src */
 401                         if (BPF_OP(code) == BPF_MOD) {
 402                                 EMIT(PPC_RAW_DIVWU(b2p[TMP_REG_1], dst_reg, src_reg));
 403                                 EMIT(PPC_RAW_MULW(b2p[TMP_REG_1], src_reg,
 404                                                 b2p[TMP_REG_1]));
 405                                 EMIT(PPC_RAW_SUB(dst_reg, dst_reg, b2p[TMP_REG_1]));
 406                         } else
 407                                 EMIT(PPC_RAW_DIVWU(dst_reg, dst_reg, src_reg));
 408                         goto bpf_alu32_trunc;
 409                 case BPF_ALU64 | BPF_DIV | BPF_X: /* dst /= src */
 410                 case BPF_ALU64 | BPF_MOD | BPF_X: /* dst %= src */
 411                         if (BPF_OP(code) == BPF_MOD) {
 412                                 EMIT(PPC_RAW_DIVDU(b2p[TMP_REG_1], dst_reg, src_reg));
 413                                 EMIT(PPC_RAW_MULD(b2p[TMP_REG_1], src_reg,
 414                                                 b2p[TMP_REG_1]));
 415                                 EMIT(PPC_RAW_SUB(dst_reg, dst_reg, b2p[TMP_REG_1]));
 416                         } else
 417                                 EMIT(PPC_RAW_DIVDU(dst_reg, dst_reg, src_reg));
 418                         break;
 419                 case BPF_ALU | BPF_MOD | BPF_K: /* (u32) dst %= (u32) imm */
 420                 case BPF_ALU | BPF_DIV | BPF_K: /* (u32) dst /= (u32) imm */
 421                 case BPF_ALU64 | BPF_MOD | BPF_K: /* dst %= imm */
 422                 case BPF_ALU64 | BPF_DIV | BPF_K: /* dst /= imm */
 423                         if (imm == 0)
 424                                 return -EINVAL;
 425                         if (imm == 1) {
 426                                 if (BPF_OP(code) == BPF_DIV) {
 427                                         goto bpf_alu32_trunc;
 428                                 } else {
 429                                         EMIT(PPC_RAW_LI(dst_reg, 0));
 430                                         break;
 431                                 }
 432                         }
 433
 434                         PPC_LI32(b2p[TMP_REG_1], imm);
 435                         switch (BPF_CLASS(code)) {
 436                         case BPF_ALU:
 437                                 if (BPF_OP(code) == BPF_MOD) {
 438                                         EMIT(PPC_RAW_DIVWU(b2p[TMP_REG_2],
 439                                                         dst_reg,
 440                                                         b2p[TMP_REG_1]));
 441                                         EMIT(PPC_RAW_MULW(b2p[TMP_REG_1],
 442                                                         b2p[TMP_REG_1],
 443                                                         b2p[TMP_REG_2]));
 444                                         EMIT(PPC_RAW_SUB(dst_reg, dst_reg,
 445                                                         b2p[TMP_REG_1]));
 446                                 } else
 447                                         EMIT(PPC_RAW_DIVWU(dst_reg, dst_reg,
 448                                                         b2p[TMP_REG_1]));
 449                                 break;
 450                         case BPF_ALU64:
 451                                 if (BPF_OP(code) == BPF_MOD) {
 452                                         EMIT(PPC_RAW_DIVDU(b2p[TMP_REG_2],
 453                                                         dst_reg,
 454                                                         b2p[TMP_REG_1]));
 455                                         EMIT(PPC_RAW_MULD(b2p[TMP_REG_1],
 456                                                         b2p[TMP_REG_1],
 457                                                         b2p[TMP_REG_2]));
 458                                         EMIT(PPC_RAW_SUB(dst_reg, dst_reg,
 459                                                         b2p[TMP_REG_1]));
 460                                 } else
 461                                         EMIT(PPC_RAW_DIVDU(dst_reg, dst_reg,
 462                                                         b2p[TMP_REG_1]));
 463                                 break;
 464                         }
 465                         goto bpf_alu32_trunc;
 466                 case BPF_ALU | BPF_NEG: /* (u32) dst = -dst */
 467                 case BPF_ALU64 | BPF_NEG: /* dst = -dst */
 468                         EMIT(PPC_RAW_NEG(dst_reg, dst_reg));
 469                         goto bpf_alu32_trunc;
 470
 471                 /*
 472                  * Logical operations: AND/OR/XOR/[A]LSH/[A]RSH
 473                  */
 474                 case BPF_ALU | BPF_AND | BPF_X: /* (u32) dst = dst & src */
 475                 case BPF_ALU64 | BPF_AND | BPF_X: /* dst = dst & src */
 476                         EMIT(PPC_RAW_AND(dst_reg, dst_reg, src_reg));
 477                         goto bpf_alu32_trunc;
 478                 case BPF_ALU | BPF_AND | BPF_K: /* (u32) dst = dst & imm */
 479                 case BPF_ALU64 | BPF_AND | BPF_K: /* dst = dst & imm */
 480                         if (!IMM_H(imm))
 481                                 EMIT(PPC_RAW_ANDI(dst_reg, dst_reg, IMM_L(imm)));
 482                         else {
 483                                 /* Sign-extended */
 484                                 PPC_LI32(b2p[TMP_REG_1], imm);
 485                                 EMIT(PPC_RAW_AND(dst_reg, dst_reg, b2p[TMP_REG_1]));
 486                         }
 487                         goto bpf_alu32_trunc;
 488                 case BPF_ALU | BPF_OR | BPF_X: /* dst = (u32) dst | (u32) src */
 489                 case BPF_ALU64 | BPF_OR | BPF_X: /* dst = dst | src */
 490                         EMIT(PPC_RAW_OR(dst_reg, dst_reg, src_reg));
 491                         goto bpf_alu32_trunc;
 492                 case BPF_ALU | BPF_OR | BPF_K:/* dst = (u32) dst | (u32) imm */
 493                 case BPF_ALU64 | BPF_OR | BPF_K:/* dst = dst | imm */
 494                         if (imm < 0 && BPF_CLASS(code) == BPF_ALU64) {
 495                                 /* Sign-extended */
 496                                 PPC_LI32(b2p[TMP_REG_1], imm);
 497                                 EMIT(PPC_RAW_OR(dst_reg, dst_reg, b2p[TMP_REG_1]));
 498                         } else {
 499                                 if (IMM_L(imm))
 500                                         EMIT(PPC_RAW_ORI(dst_reg, dst_reg, IMM_L(imm)));
 501                                 if (IMM_H(imm))
 502                                         EMIT(PPC_RAW_ORIS(dst_reg, dst_reg, IMM_H(imm)));
 503                         }
 504                         goto bpf_alu32_trunc;
 505                 case BPF_ALU | BPF_XOR | BPF_X: /* (u32) dst ^= src */
 506                 case BPF_ALU64 | BPF_XOR | BPF_X: /* dst ^= src */
 507                         EMIT(PPC_RAW_XOR(dst_reg, dst_reg, src_reg));
 508                         goto bpf_alu32_trunc;
 509                 case BPF_ALU | BPF_XOR | BPF_K: /* (u32) dst ^= (u32) imm */
 510                 case BPF_ALU64 | BPF_XOR | BPF_K: /* dst ^= imm */
 511                         if (imm < 0 && BPF_CLASS(code) == BPF_ALU64) {
 512                                 /* Sign-extended */
 513                                 PPC_LI32(b2p[TMP_REG_1], imm);
 514                                 EMIT(PPC_RAW_XOR(dst_reg, dst_reg, b2p[TMP_REG_1]));
 515                         } else {
 516                                 if (IMM_L(imm))
 517                                         EMIT(PPC_RAW_XORI(dst_reg, dst_reg, IMM_L(imm)));
 518                                 if (IMM_H(imm))
 519                                         EMIT(PPC_RAW_XORIS(dst_reg, dst_reg, IMM_H(imm)));
 520                         }
 521                         goto bpf_alu32_trunc;
 522                 case BPF_ALU | BPF_LSH | BPF_X: /* (u32) dst <<= (u32) src */
 523                         /* slw clears top 32 bits */
 524                         EMIT(PPC_RAW_SLW(dst_reg, dst_reg, src_reg));
 525                         /* skip zero extension move, but set address map. */
 526                         if (insn_is_zext(&insn[i + 1]))
 527                                 addrs[++i] = ctx->idx * 4;
 528                         break;
 529                 case BPF_ALU64 | BPF_LSH | BPF_X: /* dst <<= src; */
 530                         EMIT(PPC_RAW_SLD(dst_reg, dst_reg, src_reg));
 531                         break;
 532                 case BPF_ALU | BPF_LSH | BPF_K: /* (u32) dst <<== (u32) imm */
 533                         /* with imm 0, we still need to clear top 32 bits */
 534                         EMIT(PPC_RAW_SLWI(dst_reg, dst_reg, imm));
 535                         if (insn_is_zext(&insn[i + 1]))
 536                                 addrs[++i] = ctx->idx * 4;
 537                         break;
 538                 case BPF_ALU64 | BPF_LSH | BPF_K: /* dst <<== imm */
 539                         if (imm != 0)
 540                                 EMIT(PPC_RAW_SLDI(dst_reg, dst_reg, imm));
 541                         break;
 542                 case BPF_ALU | BPF_RSH | BPF_X: /* (u32) dst >>= (u32) src */
 543                         EMIT(PPC_RAW_SRW(dst_reg, dst_reg, src_reg));
 544                         if (insn_is_zext(&insn[i + 1]))
 545                                 addrs[++i] = ctx->idx * 4;
 546                         break;
 547                 case BPF_ALU64 | BPF_RSH | BPF_X: /* dst >>= src */
 548                         EMIT(PPC_RAW_SRD(dst_reg, dst_reg, src_reg));
 549                         break;
 550                 case BPF_ALU | BPF_RSH | BPF_K: /* (u32) dst >>= (u32) imm */
 551                         EMIT(PPC_RAW_SRWI(dst_reg, dst_reg, imm));
 552                         if (insn_is_zext(&insn[i + 1]))
 553                                 addrs[++i] = ctx->idx * 4;
 554                         break;
 555                 case BPF_ALU64 | BPF_RSH | BPF_K: /* dst >>= imm */
 556                         if (imm != 0)
 557                                 EMIT(PPC_RAW_SRDI(dst_reg, dst_reg, imm));
 558                         break;
 559                 case BPF_ALU | BPF_ARSH | BPF_X: /* (s32) dst >>= src */
 560                         EMIT(PPC_RAW_SRAW(dst_reg, dst_reg, src_reg));
 561                         goto bpf_alu32_trunc;
 562                 case BPF_ALU64 | BPF_ARSH | BPF_X: /* (s64) dst >>= src */
 563                         EMIT(PPC_RAW_SRAD(dst_reg, dst_reg, src_reg));
 564                         break;
 565                 case BPF_ALU | BPF_ARSH | BPF_K: /* (s32) dst >>= imm */
 566                         EMIT(PPC_RAW_SRAWI(dst_reg, dst_reg, imm));
 567                         goto bpf_alu32_trunc;
 568                 case BPF_ALU64 | BPF_ARSH | BPF_K: /* (s64) dst >>= imm */
 569                         if (imm != 0)
 570                                 EMIT(PPC_RAW_SRADI(dst_reg, dst_reg, imm));
 571                         break;
 572
 573                 /*
 574                  * MOV
 575                  */
 576                 case BPF_ALU | BPF_MOV | BPF_X: /* (u32) dst = src */
 577                 case BPF_ALU64 | BPF_MOV | BPF_X: /* dst = src */
 578                         if (imm == 1) {
 579                                 /* special mov32 for zext */
 580                                 EMIT(PPC_RAW_RLWINM(dst_reg, dst_reg, 0, 0, 31));
 581                                 break;
 582                         }
 583                         EMIT(PPC_RAW_MR(dst_reg, src_reg));
 584                         goto bpf_alu32_trunc;
 585                 case BPF_ALU | BPF_MOV | BPF_K: /* (u32) dst = imm */
 586                 case BPF_ALU64 | BPF_MOV | BPF_K: /* dst = (s64) imm */
 587                         PPC_LI32(dst_reg, imm);
 588                         if (imm < 0)
 589                                 goto bpf_alu32_trunc;
 590                         else if (insn_is_zext(&insn[i + 1]))
 591                                 addrs[++i] = ctx->idx * 4;
 592                         break;
 593
 594 bpf_alu32_trunc:
 595                 /* Truncate to 32-bits */
 596                 if (BPF_CLASS(code) == BPF_ALU && !fp->aux->verifier_zext)
 597                         EMIT(PPC_RAW_RLWINM(dst_reg, dst_reg, 0, 0, 31));
 598                 break;
 599
 600                 /*
 601                  * BPF_FROM_BE/LE
 602                  */
 603                 case BPF_ALU | BPF_END | BPF_FROM_LE:
 604                 case BPF_ALU | BPF_END | BPF_FROM_BE:
 605 #ifdef __BIG_ENDIAN__
 606                         if (BPF_SRC(code) == BPF_FROM_BE)
 607                                 goto emit_clear;
 608 #else /* !__BIG_ENDIAN__ */
 609                         if (BPF_SRC(code) == BPF_FROM_LE)
 610                                 goto emit_clear;
 611 #endif
 612                         switch (imm) {
 613                         case 16:
 614                                 /* Rotate 8 bits left & mask with 0x0000ff00 */
 615                                 EMIT(PPC_RAW_RLWINM(b2p[TMP_REG_1], dst_reg, 8, 16, 23));
 616                                 /* Rotate 8 bits right & insert LSB to reg */
 617                                 EMIT(PPC_RAW_RLWIMI(b2p[TMP_REG_1], dst_reg, 24, 24, 31));
 618                                 /* Move result back to dst_reg */
 619                                 EMIT(PPC_RAW_MR(dst_reg, b2p[TMP_REG_1]));
 620                                 break;
 621                         case 32:
 622                                 /*
 623                                  * Rotate word left by 8 bits:
 624                                  * 2 bytes are already in their final position
 625                                  * -- byte 2 and 4 (of bytes 1, 2, 3 and 4)
 626                                  */
 627                                 EMIT(PPC_RAW_RLWINM(b2p[TMP_REG_1], dst_reg, 8, 0, 31));
 628                                 /* Rotate 24 bits and insert byte 1 */
 629                                 EMIT(PPC_RAW_RLWIMI(b2p[TMP_REG_1], dst_reg, 24, 0, 7));
 630                                 /* Rotate 24 bits and insert byte 3 */
 631                                 EMIT(PPC_RAW_RLWIMI(b2p[TMP_REG_1], dst_reg, 24, 16, 23));
 632                                 EMIT(PPC_RAW_MR(dst_reg, b2p[TMP_REG_1]));
 633                                 break;
 634                         case 64:
 635                                 /*
 636                                  * Way easier and faster(?) to store the value
 637                                  * into stack and then use ldbrx
 638                                  *
 639                                  * ctx->seen will be reliable in pass2, but
 640                                  * the instructions generated will remain the
 641                                  * same across all passes
 642                                  */
 643                                 PPC_BPF_STL(dst_reg, 1, bpf_jit_stack_local(ctx));
 644                                 EMIT(PPC_RAW_ADDI(b2p[TMP_REG_1], 1, bpf_jit_stack_local(ctx)));
 645                                 EMIT(PPC_RAW_LDBRX(dst_reg, 0, b2p[TMP_REG_1]));
 646                                 break;
 647                         }
 648                         break;
 649
 650 emit_clear:
 651                         switch (imm) {
 652                         case 16:
 653                                 /* zero-extend 16 bits into 64 bits */
 654                                 EMIT(PPC_RAW_RLDICL(dst_reg, dst_reg, 0, 48));
 655                                 if (insn_is_zext(&insn[i + 1]))
 656                                         addrs[++i] = ctx->idx * 4;
 657                                 break;
 658                         case 32:
 659                                 if (!fp->aux->verifier_zext)
 660                                         /* zero-extend 32 bits into 64 bits */
 661                                         EMIT(PPC_RAW_RLDICL(dst_reg, dst_reg, 0, 32));
 662                                 break;
 663                         case 64:
 664                                 /* nop */
 665                                 break;
 666                         }
 667                         break;
 668
 669                 /*
 670                  * BPF_ST NOSPEC (speculation barrier)
 671                  */
 672                 case BPF_ST | BPF_NOSPEC:
 673                         if (!security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) ||
 674                                         !security_ftr_enabled(SEC_FTR_STF_BARRIER))
 675                                 break;
 676
 677                         switch (stf_barrier) {
 678                         case STF_BARRIER_EIEIO:
 679                                 EMIT(PPC_RAW_EIEIO() | 0x02000000);
 680                                 break;
 681                         case STF_BARRIER_SYNC_ORI:
 682                                 EMIT(PPC_RAW_SYNC());
 683                                 EMIT(PPC_RAW_LD(b2p[TMP_REG_1], _R13, 0));
 684                                 EMIT(PPC_RAW_ORI(_R31, _R31, 0));
 685                                 break;
 686                         case STF_BARRIER_FALLBACK:
 687                                 EMIT(PPC_RAW_MFLR(b2p[TMP_REG_1]));
 688                                 PPC_LI64(12, dereference_kernel_function_descriptor(bpf_stf_barrier));
 689                                 EMIT(PPC_RAW_MTCTR(12));
 690                                 EMIT(PPC_RAW_BCTRL());
 691                                 EMIT(PPC_RAW_MTLR(b2p[TMP_REG_1]));
 692                                 break;
 693                         case STF_BARRIER_NONE:
 694                                 break;
 695                         }
 696                         break;
 697
 698                 /*
 699                  * BPF_ST(X)
 700                  */
 701                 case BPF_STX | BPF_MEM | BPF_B: /* *(u8 *)(dst + off) = src */
 702                 case BPF_ST | BPF_MEM | BPF_B: /* *(u8 *)(dst + off) = imm */
 703                         if (BPF_CLASS(code) == BPF_ST) {
 704                                 EMIT(PPC_RAW_LI(b2p[TMP_REG_1], imm));
 705                                 src_reg = b2p[TMP_REG_1];
 706                         }
 707                         EMIT(PPC_RAW_STB(src_reg, dst_reg, off));
 708                         break;
 709                 case BPF_STX | BPF_MEM | BPF_H: /* (u16 *)(dst + off) = src */
 710                 case BPF_ST | BPF_MEM | BPF_H: /* (u16 *)(dst + off) = imm */
 711                         if (BPF_CLASS(code) == BPF_ST) {
 712                                 EMIT(PPC_RAW_LI(b2p[TMP_REG_1], imm));
 713                                 src_reg = b2p[TMP_REG_1];
 714                         }
 715                         EMIT(PPC_RAW_STH(src_reg, dst_reg, off));
 716                         break;
 717                 case BPF_STX | BPF_MEM | BPF_W: /* *(u32 *)(dst + off) = src */
 718                 case BPF_ST | BPF_MEM | BPF_W: /* *(u32 *)(dst + off) = imm */
 719                         if (BPF_CLASS(code) == BPF_ST) {
 720                                 PPC_LI32(b2p[TMP_REG_1], imm);
 721                                 src_reg = b2p[TMP_REG_1];
 722                         }
 723                         EMIT(PPC_RAW_STW(src_reg, dst_reg, off));
 724                         break;
 725                 case BPF_STX | BPF_MEM | BPF_DW: /* (u64 *)(dst + off) = src */
 726                 case BPF_ST | BPF_MEM | BPF_DW: /* *(u64 *)(dst + off) = imm */
 727                         if (BPF_CLASS(code) == BPF_ST) {
 728                                 PPC_LI32(b2p[TMP_REG_1], imm);
 729                                 src_reg = b2p[TMP_REG_1];
 730                         }
 731                         PPC_BPF_STL(src_reg, dst_reg, off);
 732                         break;
 733
 734                 /*
 735                  * BPF_STX ATOMIC (atomic ops)
 736                  */
 737                 case BPF_STX | BPF_ATOMIC | BPF_W:
 738                         if (imm != BPF_ADD) {
 739                                 pr_err_ratelimited(
 740                                         "eBPF filter atomic op code %02x (@%d) unsupported\n",
 741                                         code, i);
 742                                 return -ENOTSUPP;
 743                         }
 744
 745                         /* *(u32 *)(dst + off) += src */
 746
 747                         /* Get EA into TMP_REG_1 */
 748                         EMIT(PPC_RAW_ADDI(b2p[TMP_REG_1], dst_reg, off));
 749                         tmp_idx = ctx->idx * 4;
 750                         /* load value from memory into TMP_REG_2 */
 751                         EMIT(PPC_RAW_LWARX(b2p[TMP_REG_2], 0, b2p[TMP_REG_1], 0));
 752                         /* add value from src_reg into this */
 753                         EMIT(PPC_RAW_ADD(b2p[TMP_REG_2], b2p[TMP_REG_2], src_reg));
 754                         /* store result back */
 755                         EMIT(PPC_RAW_STWCX(b2p[TMP_REG_2], 0, b2p[TMP_REG_1]));
 756                         /* we're done if this succeeded */
 757                         PPC_BCC_SHORT(COND_NE, tmp_idx);
 758                         break;
 759                 case BPF_STX | BPF_ATOMIC | BPF_DW:
 760                         if (imm != BPF_ADD) {
 761                                 pr_err_ratelimited(
 762                                         "eBPF filter atomic op code %02x (@%d) unsupported\n",
 763                                         code, i);
 764                                 return -ENOTSUPP;
 765                         }
 766                         /* *(u64 *)(dst + off) += src */
 767
 768                         EMIT(PPC_RAW_ADDI(b2p[TMP_REG_1], dst_reg, off));
 769                         tmp_idx = ctx->idx * 4;
 770                         EMIT(PPC_RAW_LDARX(b2p[TMP_REG_2], 0, b2p[TMP_REG_1], 0));
 771                         EMIT(PPC_RAW_ADD(b2p[TMP_REG_2], b2p[TMP_REG_2], src_reg));
 772                         EMIT(PPC_RAW_STDCX(b2p[TMP_REG_2], 0, b2p[TMP_REG_1]));
 773                         PPC_BCC_SHORT(COND_NE, tmp_idx);
 774                         break;
 775
 776                 /*
 777                  * BPF_LDX
 778                  */
 779                 /* dst = *(u8 *)(ul) (src + off) */
 780                 case BPF_LDX | BPF_MEM | BPF_B:
 781                         EMIT(PPC_RAW_LBZ(dst_reg, src_reg, off));
 782                         if (insn_is_zext(&insn[i + 1]))
 783                                 addrs[++i] = ctx->idx * 4;
 784                         break;
 785                 /* dst = *(u16 *)(ul) (src + off) */
 786                 case BPF_LDX | BPF_MEM | BPF_H:
 787                         EMIT(PPC_RAW_LHZ(dst_reg, src_reg, off));
 788                         if (insn_is_zext(&insn[i + 1]))
 789                                 addrs[++i] = ctx->idx * 4;
 790                         break;
 791                 /* dst = *(u32 *)(ul) (src + off) */
 792                 case BPF_LDX | BPF_MEM | BPF_W:
 793                         EMIT(PPC_RAW_LWZ(dst_reg, src_reg, off));
 794                         if (insn_is_zext(&insn[i + 1]))
 795                                 addrs[++i] = ctx->idx * 4;
 796                         break;
 797                 /* dst = *(u64 *)(ul) (src + off) */
 798                 case BPF_LDX | BPF_MEM | BPF_DW:
 799                         PPC_BPF_LL(dst_reg, src_reg, off);
 800                         break;
 801
 802                 /*
 803                  * Doubleword load
 804                  * 16 byte instruction that uses two 'struct bpf_insn'
 805                  */
 806                 case BPF_LD | BPF_IMM | BPF_DW: /* dst = (u64) imm */
 807                         imm64 = ((u64)(u32) insn[i].imm) |
 808                                     (((u64)(u32) insn[i+1].imm) << 32);
 809                         /* Adjust for two bpf instructions */
 810                         addrs[++i] = ctx->idx * 4;
 811                         PPC_LI64(dst_reg, imm64);
 812                         break;
 813
 814                 /*
 815                  * Return/Exit
 816                  */
 817                 case BPF_JMP | BPF_EXIT:
 818                         /*
 819                          * If this isn't the very last instruction, branch to
 820                          * the epilogue. If we _are_ the last instruction,
 821                          * we'll just fall through to the epilogue.
 822                          */
 823                         if (i != flen - 1)
 824                                 PPC_JMP(exit_addr);
 825                         /* else fall through to the epilogue */
 826                         break;
 827
 828                 /*
 829                  * Call kernel helper or bpf function
 830                  */
 831                 case BPF_JMP | BPF_CALL:
 832                         ctx->seen |= SEEN_FUNC;
 833
 834                         ret = bpf_jit_get_func_addr(fp, &insn[i], extra_pass,
 835                                                     &func_addr, &func_addr_fixed);
 836                         if (ret < 0)
 837                                 return ret;
 838
 839                         if (func_addr_fixed)
 840                                 bpf_jit_emit_func_call_hlp(image, ctx, func_addr);
 841                         else
 842                                 bpf_jit_emit_func_call_rel(image, ctx, func_addr);
 843                         /* move return value from r3 to BPF_REG_0 */
 844                         EMIT(PPC_RAW_MR(b2p[BPF_REG_0], 3));
 845                         break;
 846
 847                 /*
 848                  * Jumps and branches
 849                  */
 850                 case BPF_JMP | BPF_JA:
 851                         PPC_JMP(addrs[i + 1 + off]);
 852                         break;
 853
 854                 case BPF_JMP | BPF_JGT | BPF_K:
 855                 case BPF_JMP | BPF_JGT | BPF_X:
 856                 case BPF_JMP | BPF_JSGT | BPF_K:
 857                 case BPF_JMP | BPF_JSGT | BPF_X:
 858                 case BPF_JMP32 | BPF_JGT | BPF_K:
 859                 case BPF_JMP32 | BPF_JGT | BPF_X:
 860                 case BPF_JMP32 | BPF_JSGT | BPF_K:
 861                 case BPF_JMP32 | BPF_JSGT | BPF_X:
 862                         true_cond = COND_GT;
 863                         goto cond_branch;
 864                 case BPF_JMP | BPF_JLT | BPF_K:
 865                 case BPF_JMP | BPF_JLT | BPF_X:
 866                 case BPF_JMP | BPF_JSLT | BPF_K:
 867                 case BPF_JMP | BPF_JSLT | BPF_X:
 868                 case BPF_JMP32 | BPF_JLT | BPF_K:
 869                 case BPF_JMP32 | BPF_JLT | BPF_X:
 870                 case BPF_JMP32 | BPF_JSLT | BPF_K:
 871                 case BPF_JMP32 | BPF_JSLT | BPF_X:
 872                         true_cond = COND_LT;
 873                         goto cond_branch;
 874                 case BPF_JMP | BPF_JGE | BPF_K:
 875                 case BPF_JMP | BPF_JGE | BPF_X:
 876                 case BPF_JMP | BPF_JSGE | BPF_K:
 877                 case BPF_JMP | BPF_JSGE | BPF_X:
 878                 case BPF_JMP32 | BPF_JGE | BPF_K:
 879                 case BPF_JMP32 | BPF_JGE | BPF_X:
 880                 case BPF_JMP32 | BPF_JSGE | BPF_K:
 881                 case BPF_JMP32 | BPF_JSGE | BPF_X:
 882                         true_cond = COND_GE;
 883                         goto cond_branch;
 884                 case BPF_JMP | BPF_JLE | BPF_K:
 885                 case BPF_JMP | BPF_JLE | BPF_X:
 886                 case BPF_JMP | BPF_JSLE | BPF_K:
 887                 case BPF_JMP | BPF_JSLE | BPF_X:
 888                 case BPF_JMP32 | BPF_JLE | BPF_K:
 889                 case BPF_JMP32 | BPF_JLE | BPF_X:
 890                 case BPF_JMP32 | BPF_JSLE | BPF_K:
 891                 case BPF_JMP32 | BPF_JSLE | BPF_X:
 892                         true_cond = COND_LE;
 893                         goto cond_branch;
 894                 case BPF_JMP | BPF_JEQ | BPF_K:
 895                 case BPF_JMP | BPF_JEQ | BPF_X:
 896                 case BPF_JMP32 | BPF_JEQ | BPF_K:
 897                 case BPF_JMP32 | BPF_JEQ | BPF_X:
 898                         true_cond = COND_EQ;
 899                         goto cond_branch;
 900                 case BPF_JMP | BPF_JNE | BPF_K:
 901                 case BPF_JMP | BPF_JNE | BPF_X:
 902                 case BPF_JMP32 | BPF_JNE | BPF_K:
 903                 case BPF_JMP32 | BPF_JNE | BPF_X:
 904                         true_cond = COND_NE;
 905                         goto cond_branch;
 906                 case BPF_JMP | BPF_JSET | BPF_K:
 907                 case BPF_JMP | BPF_JSET | BPF_X:
 908                 case BPF_JMP32 | BPF_JSET | BPF_K:
 909                 case BPF_JMP32 | BPF_JSET | BPF_X:
 910                         true_cond = COND_NE;
 911                         /* Fall through */
 912
 913 cond_branch:
 914                         switch (code) {
 915                         case BPF_JMP | BPF_JGT | BPF_X:
 916                         case BPF_JMP | BPF_JLT | BPF_X:
 917                         case BPF_JMP | BPF_JGE | BPF_X:
 918                         case BPF_JMP | BPF_JLE | BPF_X:
 919                         case BPF_JMP | BPF_JEQ | BPF_X:
 920                         case BPF_JMP | BPF_JNE | BPF_X:
 921                         case BPF_JMP32 | BPF_JGT | BPF_X:
 922                         case BPF_JMP32 | BPF_JLT | BPF_X:
 923                         case BPF_JMP32 | BPF_JGE | BPF_X:
 924                         case BPF_JMP32 | BPF_JLE | BPF_X:
 925                         case BPF_JMP32 | BPF_JEQ | BPF_X:
 926                         case BPF_JMP32 | BPF_JNE | BPF_X:
 927                                 /* unsigned comparison */
 928                                 if (BPF_CLASS(code) == BPF_JMP32)
 929                                         EMIT(PPC_RAW_CMPLW(dst_reg, src_reg));
 930                                 else
 931                                         EMIT(PPC_RAW_CMPLD(dst_reg, src_reg));
 932                                 break;
 933                         case BPF_JMP | BPF_JSGT | BPF_X:
 934                         case BPF_JMP | BPF_JSLT | BPF_X:
 935                         case BPF_JMP | BPF_JSGE | BPF_X:
 936                         case BPF_JMP | BPF_JSLE | BPF_X:
 937                         case BPF_JMP32 | BPF_JSGT | BPF_X:
 938                         case BPF_JMP32 | BPF_JSLT | BPF_X:
 939                         case BPF_JMP32 | BPF_JSGE | BPF_X:
 940                         case BPF_JMP32 | BPF_JSLE | BPF_X:
 941                                 /* signed comparison */
 942                                 if (BPF_CLASS(code) == BPF_JMP32)
 943                                         EMIT(PPC_RAW_CMPW(dst_reg, src_reg));
 944                                 else
 945                                         EMIT(PPC_RAW_CMPD(dst_reg, src_reg));
 946                                 break;
 947                         case BPF_JMP | BPF_JSET | BPF_X:
 948                         case BPF_JMP32 | BPF_JSET | BPF_X:
 949                                 if (BPF_CLASS(code) == BPF_JMP) {
 950                                         EMIT(PPC_RAW_AND_DOT(b2p[TMP_REG_1], dst_reg,
 951                                                     src_reg));
 952                                 } else {
 953                                         int tmp_reg = b2p[TMP_REG_1];
 954
 955                                         EMIT(PPC_RAW_AND(tmp_reg, dst_reg, src_reg));
 956                                         EMIT(PPC_RAW_RLWINM_DOT(tmp_reg, tmp_reg, 0, 0,
 957                                                        31));
 958                                 }
 959                                 break;
 960                         case BPF_JMP | BPF_JNE | BPF_K:
 961                         case BPF_JMP | BPF_JEQ | BPF_K:
 962                         case BPF_JMP | BPF_JGT | BPF_K:
 963                         case BPF_JMP | BPF_JLT | BPF_K:
 964                         case BPF_JMP | BPF_JGE | BPF_K:
 965                         case BPF_JMP | BPF_JLE | BPF_K:
 966                         case BPF_JMP32 | BPF_JNE | BPF_K:
 967                         case BPF_JMP32 | BPF_JEQ | BPF_K:
 968                         case BPF_JMP32 | BPF_JGT | BPF_K:
 969                         case BPF_JMP32 | BPF_JLT | BPF_K:
 970                         case BPF_JMP32 | BPF_JGE | BPF_K:
 971                         case BPF_JMP32 | BPF_JLE | BPF_K:
 972                         {
 973                                 bool is_jmp32 = BPF_CLASS(code) == BPF_JMP32;
 974
 975                                 /*
 976                                  * Need sign-extended load, so only positive
 977                                  * values can be used as imm in cmpldi
 978                                  */
 979                                 if (imm >= 0 && imm < 32768) {
 980                                         if (is_jmp32)
 981                                                 EMIT(PPC_RAW_CMPLWI(dst_reg, imm));
 982                                         else
 983                                                 EMIT(PPC_RAW_CMPLDI(dst_reg, imm));
 984                                 } else {
 985                                         /* sign-extending load */
 986                                         PPC_LI32(b2p[TMP_REG_1], imm);
 987                                         /* ... but unsigned comparison */
 988                                         if (is_jmp32)
 989                                                 EMIT(PPC_RAW_CMPLW(dst_reg,
 990                                                           b2p[TMP_REG_1]));
 991                                         else
 992                                                 EMIT(PPC_RAW_CMPLD(dst_reg,
 993                                                           b2p[TMP_REG_1]));
 994                                 }
 995                                 break;
 996                         }
 997                         case BPF_JMP | BPF_JSGT | BPF_K:
 998                         case BPF_JMP | BPF_JSLT | BPF_K:
 999                         case BPF_JMP | BPF_JSGE | BPF_K:
1000                         case BPF_JMP | BPF_JSLE | BPF_K:
1001                         case BPF_JMP32 | BPF_JSGT | BPF_K:
1002                         case BPF_JMP32 | BPF_JSLT | BPF_K:
1003                         case BPF_JMP32 | BPF_JSGE | BPF_K:
1004                         case BPF_JMP32 | BPF_JSLE | BPF_K:
1005                         {
1006                                 bool is_jmp32 = BPF_CLASS(code) == BPF_JMP32;
1007
1008                                 /*
1009                                  * signed comparison, so any 16-bit value
1010                                  * can be used in cmpdi
1011                                  */
1012                                 if (imm >= -32768 && imm < 32768) {
1013                                         if (is_jmp32)
1014                                                 EMIT(PPC_RAW_CMPWI(dst_reg, imm));
1015                                         else
1016                                                 EMIT(PPC_RAW_CMPDI(dst_reg, imm));
1017                                 } else {
1018                                         PPC_LI32(b2p[TMP_REG_1], imm);
1019                                         if (is_jmp32)
1020                                                 EMIT(PPC_RAW_CMPW(dst_reg,
1021                                                          b2p[TMP_REG_1]));
1022                                         else
1023                                                 EMIT(PPC_RAW_CMPD(dst_reg,
1024                                                          b2p[TMP_REG_1]));
1025                                 }
1026                                 break;
1027                         }
1028                         case BPF_JMP | BPF_JSET | BPF_K:
1029                         case BPF_JMP32 | BPF_JSET | BPF_K:
1030                                 /* andi does not sign-extend the immediate */
1031                                 if (imm >= 0 && imm < 32768)
1032                                         /* PPC_ANDI is _only/always_ dot-form */
1033                                         EMIT(PPC_RAW_ANDI(b2p[TMP_REG_1], dst_reg, imm));
1034                                 else {
1035                                         int tmp_reg = b2p[TMP_REG_1];
1036
1037                                         PPC_LI32(tmp_reg, imm);
1038                                         if (BPF_CLASS(code) == BPF_JMP) {
1039                                                 EMIT(PPC_RAW_AND_DOT(tmp_reg, dst_reg,
1040                                                             tmp_reg));
1041                                         } else {
1042                                                 EMIT(PPC_RAW_AND(tmp_reg, dst_reg,
1043                                                         tmp_reg));
1044                                                 EMIT(PPC_RAW_RLWINM_DOT(tmp_reg, tmp_reg,
1045                                                                0, 0, 31));
1046                                         }
1047                                 }
1048                                 break;
1049                         }
1050                         PPC_BCC(true_cond, addrs[i + 1 + off]);
1051                         break;
1052
1053                 /*
1054                  * Tail call
1055                  */
1056                 case BPF_JMP | BPF_TAIL_CALL:
1057                         ctx->seen |= SEEN_TAILCALL;
1058                         ret = bpf_jit_emit_tail_call(image, ctx, addrs[i + 1]);
1059                         if (ret < 0)
1060                                 return ret;
1061                         break;
1062
1063                 default:
1064                         /*
1065                          * The filter contains something cruel & unusual.
1066                          * We don't handle it, but also there shouldn't be
1067                          * anything missing from our list.
1068                          */
1069                         pr_err_ratelimited("eBPF filter opcode %04x (@%d) unsupported\n",
1070                                         code, i);
1071                         return -ENOTSUPP;
1072                 }
1073         }
1074
1075         /* Set end-of-body-code address for exit. */
1076         addrs[i] = ctx->idx * 4;
1077
1078         return 0;
1079 }