projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 2809a208 DM |
1 | #include <linux/moduleloader.h> |
| 2 | #include <linux/workqueue.h> | |
| 3 | #include <linux/netdevice.h> | |
| 4 | #include <linux/filter.h> | |
| 5 | #include <linux/cache.h> | |
| 6 | ||
| 7 | #include <asm/cacheflush.h> | |
| 8 | #include <asm/ptrace.h> | |
| 9 | ||
| 10 | #include "bpf_jit.h" | |
| 11 | ||
| 12 | int bpf_jit_enable __read_mostly; | |
| 13 | ||
| 2809a208 DM |
14 | static inline bool is_simm13(unsigned int value) |
| 15 | { | |
| 16 | return value + 0x1000 < 0x2000; | |
| 17 | } | |
| 18 | ||
| 19 | static void bpf_flush_icache(void *start_, void *end_) | |
| 20 | { | |
| 21 | #ifdef CONFIG_SPARC64 | |
| 22 | /* Cheetah's I-cache is fully coherent. */ | |
| 23 | if (tlb_type == spitfire) { | |
| 24 | unsigned long start = (unsigned long) start_; | |
| 25 | unsigned long end = (unsigned long) end_; | |
| 26 | ||
| 27 | start &= ~7UL; | |
| 28 | end = (end + 7UL) & ~7UL; | |
| 29 | while (start < end) { | |
| 30 | flushi(start); | |
| 31 | start += 32; | |
| 32 | } | |
| 33 | } | |
| 34 | #endif | |
| 35 | } | |
| 36 | ||
| 37 | #define SEEN_DATAREF 1 /* might call external helpers */ | |
| 38 | #define SEEN_XREG 2 /* ebx is used */ | |
| 39 | #define SEEN_MEM 4 /* use mem[] for temporary storage */ | |
| 40 | ||
| 41 | #define S13(X) ((X) & 0x1fff) | |
| 42 | #define IMMED 0x00002000 | |
| 43 | #define RD(X) ((X) << 25) | |
| 44 | #define RS1(X) ((X) << 14) | |
| 45 | #define RS2(X) ((X)) | |
| 46 | #define OP(X) ((X) << 30) | |
| 47 | #define OP2(X) ((X) << 22) | |
| 48 | #define OP3(X) ((X) << 19) | |
| 49 | #define COND(X) ((X) << 25) | |
| 50 | #define F1(X) OP(X) | |
| 51 | #define F2(X, Y) (OP(X) | OP2(Y)) | |
| 52 | #define F3(X, Y) (OP(X) | OP3(Y)) | |
| 53 | ||
| 584c5e2a DM |
54 | #define CONDN COND(0x0) |
| 55 | #define CONDE COND(0x1) | |
| 56 | #define CONDLE COND(0x2) | |
| 57 | #define CONDL COND(0x3) | |
| 58 | #define CONDLEU COND(0x4) | |
| 59 | #define CONDCS COND(0x5) | |
| 60 | #define CONDNEG COND(0x6) | |
| 61 | #define CONDVC COND(0x7) | |
| 62 | #define CONDA COND(0x8) | |
| 63 | #define CONDNE COND(0x9) | |
| 64 | #define CONDG COND(0xa) | |
| 65 | #define CONDGE COND(0xb) | |
| 66 | #define CONDGU COND(0xc) | |
| 67 | #define CONDCC COND(0xd) | |
| 68 | #define CONDPOS COND(0xe) | |
| 69 | #define CONDVS COND(0xf) | |
| 2809a208 DM |
70 | |
| 71 | #define CONDGEU CONDCC | |
| 72 | #define CONDLU CONDCS | |
| 73 | ||
| 74 | #define WDISP22(X) (((X) >> 2) & 0x3fffff) | |
| 75 | ||
| 76 | #define BA (F2(0, 2) | CONDA) | |
| 77 | #define BGU (F2(0, 2) | CONDGU) | |
| 78 | #define BLEU (F2(0, 2) | CONDLEU) | |
| 79 | #define BGEU (F2(0, 2) | CONDGEU) | |
| 80 | #define BLU (F2(0, 2) | CONDLU) | |
| 81 | #define BE (F2(0, 2) | CONDE) | |
| 82 | #define BNE (F2(0, 2) | CONDNE) | |
| 83 | ||
| 84 | #ifdef CONFIG_SPARC64 | |
| 85 | #define BNE_PTR (F2(0, 1) | CONDNE | (2 << 20)) | |
| 86 | #else | |
| 87 | #define BNE_PTR BNE | |
| 88 | #endif | |
| 89 | ||
| 90 | #define SETHI(K, REG) \ | |
| 91 | (F2(0, 0x4) | RD(REG) | (((K) >> 10) & 0x3fffff)) | |
| 92 | #define OR_LO(K, REG) \ | |
| 93 | (F3(2, 0x02) | IMMED | RS1(REG) | ((K) & 0x3ff) | RD(REG)) | |
| 94 | ||
| 95 | #define ADD F3(2, 0x00) | |
| 96 | #define AND F3(2, 0x01) | |
| 97 | #define ANDCC F3(2, 0x11) | |
| 98 | #define OR F3(2, 0x02) | |
| 99 | #define SUB F3(2, 0x04) | |
| 100 | #define SUBCC F3(2, 0x14) | |
| 101 | #define MUL F3(2, 0x0a) /* umul */ | |
| 102 | #define DIV F3(2, 0x0e) /* udiv */ | |
| 103 | #define SLL F3(2, 0x25) | |
| 104 | #define SRL F3(2, 0x26) | |
| 105 | #define JMPL F3(2, 0x38) | |
| 106 | #define CALL F1(1) | |
| 107 | #define BR F2(0, 0x01) | |
| 108 | #define RD_Y F3(2, 0x28) | |
| 109 | #define WR_Y F3(2, 0x30) | |
| 110 | ||
| 111 | #define LD32 F3(3, 0x00) | |
| 112 | #define LD8 F3(3, 0x01) | |
| 113 | #define LD16 F3(3, 0x02) | |
| 114 | #define LD64 F3(3, 0x0b) | |
| 115 | #define ST32 F3(3, 0x04) | |
| 116 | ||
| 117 | #ifdef CONFIG_SPARC64 | |
| 118 | #define LDPTR LD64 | |
| 119 | #define BASE_STACKFRAME 176 | |
| 120 | #else | |
| 121 | #define LDPTR LD32 | |
| 122 | #define BASE_STACKFRAME 96 | |
| 123 | #endif | |
| 124 | ||
| 125 | #define LD32I (LD32 | IMMED) | |
| 126 | #define LD8I (LD8 | IMMED) | |
| 127 | #define LD16I (LD16 | IMMED) | |
| 128 | #define LD64I (LD64 | IMMED) | |
| 129 | #define LDPTRI (LDPTR | IMMED) | |
| 130 | #define ST32I (ST32 | IMMED) | |
| 131 | ||
| 132 | #define emit_nop() \ | |
| 133 | do { \ | |
| 134 | *prog++ = SETHI(0, G0); \ | |
| 135 | } while (0) | |
| 136 | ||
| 137 | #define emit_neg() \ | |
| 138 | do { /* sub %g0, r_A, r_A */ \ | |
| 139 | *prog++ = SUB | RS1(G0) | RS2(r_A) | RD(r_A); \ | |
| 140 | } while (0) | |
| 141 | ||
| 142 | #define emit_reg_move(FROM, TO) \ | |
| 143 | do { /* or %g0, FROM, TO */ \ | |
| 144 | *prog++ = OR | RS1(G0) | RS2(FROM) | RD(TO); \ | |
| 145 | } while (0) | |
| 146 | ||
| 147 | #define emit_clear(REG) \ | |
| 148 | do { /* or %g0, %g0, REG */ \ | |
| 149 | *prog++ = OR | RS1(G0) | RS2(G0) | RD(REG); \ | |
| 150 | } while (0) | |
| 151 | ||
| 152 | #define emit_set_const(K, REG) \ | |
| 153 | do { /* sethi %hi(K), REG */ \ | |
| 154 | *prog++ = SETHI(K, REG); \ | |
| 155 | /* or REG, %lo(K), REG */ \ | |
| 156 | *prog++ = OR_LO(K, REG); \ | |
| 157 | } while (0) | |
| 158 | ||
| 159 | /* Emit | |
| 160 | * | |
| 584c5e2a | 161 | * OP r_A, r_X, r_A |
| 2809a208 DM |
162 | */ |
| 163 | #define emit_alu_X(OPCODE) \ | |
| 164 | do { \ | |
| 165 | seen |= SEEN_XREG; \ | |
| 166 | *prog++ = OPCODE | RS1(r_A) | RS2(r_X) | RD(r_A); \ | |
| 167 | } while (0) | |
| 168 | ||
| 169 | /* Emit either: | |
| 170 | * | |
| 171 | * OP r_A, K, r_A | |
| 172 | * | |
| 173 | * or | |
| 174 | * | |
| 175 | * sethi %hi(K), r_TMP | |
| 176 | * or r_TMP, %lo(K), r_TMP | |
| 177 | * OP r_A, r_TMP, r_A | |
| 178 | * | |
| 179 | * depending upon whether K fits in a signed 13-bit | |
| 180 | * immediate instruction field. Emit nothing if K | |
| 181 | * is zero. | |
| 182 | */ | |
| 183 | #define emit_alu_K(OPCODE, K) \ | |
| 584c5e2a | 184 | do { \ |
| 2809a208 DM |
185 | if (K) { \ |
| 186 | unsigned int _insn = OPCODE; \ | |
| 187 | _insn |= RS1(r_A) | RD(r_A); \ | |
| 188 | if (is_simm13(K)) { \ | |
| 189 | *prog++ = _insn | IMMED | S13(K); \ | |
| 190 | } else { \ | |
| 191 | emit_set_const(K, r_TMP); \ | |
| 192 | *prog++ = _insn | RS2(r_TMP); \ | |
| 584c5e2a | 193 | } \ |
| 2809a208 DM |
194 | } \ |
| 195 | } while (0) | |
| 196 | ||
| 197 | #define emit_loadimm(K, DEST) \ | |
| 198 | do { \ | |
| 199 | if (is_simm13(K)) { \ | |
| 200 | /* or %g0, K, DEST */ \ | |
| 201 | *prog++ = OR | IMMED | RS1(G0) | S13(K) | RD(DEST); \ | |
| 202 | } else { \ | |
| 203 | emit_set_const(K, DEST); \ | |
| 204 | } \ | |
| 205 | } while (0) | |
| 206 | ||
| 207 | #define emit_loadptr(BASE, STRUCT, FIELD, DEST) \ | |
| 208 | do { unsigned int _off = offsetof(STRUCT, FIELD); \ | |
| 209 | BUILD_BUG_ON(FIELD_SIZEOF(STRUCT, FIELD) != sizeof(void *)); \ | |
| 210 | *prog++ = LDPTRI | RS1(BASE) | S13(_off) | RD(DEST); \ | |
| 584c5e2a | 211 | } while (0) |
| 2809a208 DM |
212 | |
| 213 | #define emit_load32(BASE, STRUCT, FIELD, DEST) \ | |
| 214 | do { unsigned int _off = offsetof(STRUCT, FIELD); \ | |
| 215 | BUILD_BUG_ON(FIELD_SIZEOF(STRUCT, FIELD) != sizeof(u32)); \ | |
| 216 | *prog++ = LD32I | RS1(BASE) | S13(_off) | RD(DEST); \ | |
| 584c5e2a | 217 | } while (0) |
| 2809a208 DM |
218 | |
| 219 | #define emit_load16(BASE, STRUCT, FIELD, DEST) \ | |
| 220 | do { unsigned int _off = offsetof(STRUCT, FIELD); \ | |
| 221 | BUILD_BUG_ON(FIELD_SIZEOF(STRUCT, FIELD) != sizeof(u16)); \ | |
| 222 | *prog++ = LD16I | RS1(BASE) | S13(_off) | RD(DEST); \ | |
| 584c5e2a | 223 | } while (0) |
| 2809a208 DM |
224 | |
| 225 | #define __emit_load8(BASE, STRUCT, FIELD, DEST) \ | |
| 226 | do { unsigned int _off = offsetof(STRUCT, FIELD); \ | |
| 227 | *prog++ = LD8I | RS1(BASE) | S13(_off) | RD(DEST); \ | |
| 584c5e2a | 228 | } while (0) |
| 2809a208 DM |
229 | |
| 230 | #define emit_load8(BASE, STRUCT, FIELD, DEST) \ | |
| 231 | do { BUILD_BUG_ON(FIELD_SIZEOF(STRUCT, FIELD) != sizeof(u8)); \ | |
| 232 | __emit_load8(BASE, STRUCT, FIELD, DEST); \ | |
| 584c5e2a | 233 | } while (0) |
| 2809a208 DM |
234 | |
| 235 | #define emit_ldmem(OFF, DEST) \ | |
| 236 | do { *prog++ = LD32I | RS1(FP) | S13(-(OFF)) | RD(DEST); \ | |
| 584c5e2a | 237 | } while (0) |
| 2809a208 DM |
238 | |
| 239 | #define emit_stmem(OFF, SRC) \ | |
| 240 | do { *prog++ = LD32I | RS1(FP) | S13(-(OFF)) | RD(SRC); \ | |
| 584c5e2a | 241 | } while (0) |
| 2809a208 | 242 | |
| 2809a208 DM |
243 | #ifdef CONFIG_SMP |
| 244 | #ifdef CONFIG_SPARC64 | |
| 245 | #define emit_load_cpu(REG) \ | |
| 246 | emit_load16(G6, struct thread_info, cpu, REG) | |
| 247 | #else | |
| 248 | #define emit_load_cpu(REG) \ | |
| 249 | emit_load32(G6, struct thread_info, cpu, REG) | |
| 250 | #endif | |
| 251 | #else | |
| 252 | #define emit_load_cpu(REG) emit_clear(REG) | |
| 253 | #endif | |
| 254 | ||
| 255 | #define emit_skb_loadptr(FIELD, DEST) \ | |
| 256 | emit_loadptr(r_SKB, struct sk_buff, FIELD, DEST) | |
| 257 | #define emit_skb_load32(FIELD, DEST) \ | |
| 258 | emit_load32(r_SKB, struct sk_buff, FIELD, DEST) | |
| 259 | #define emit_skb_load16(FIELD, DEST) \ | |
| 260 | emit_load16(r_SKB, struct sk_buff, FIELD, DEST) | |
| 261 | #define __emit_skb_load8(FIELD, DEST) \ | |
| 262 | __emit_load8(r_SKB, struct sk_buff, FIELD, DEST) | |
| 263 | #define emit_skb_load8(FIELD, DEST) \ | |
| 264 | emit_load8(r_SKB, struct sk_buff, FIELD, DEST) | |
| 265 | ||
| 266 | #define emit_jmpl(BASE, IMM_OFF, LREG) \ | |
| 267 | *prog++ = (JMPL | IMMED | RS1(BASE) | S13(IMM_OFF) | RD(LREG)) | |
| 268 | ||
| 269 | #define emit_call(FUNC) \ | |
| 270 | do { void *_here = image + addrs[i] - 8; \ | |
| 271 | unsigned int _off = (void *)(FUNC) - _here; \ | |
| 272 | *prog++ = CALL | (((_off) >> 2) & 0x3fffffff); \ | |
| 273 | emit_nop(); \ | |
| 274 | } while (0) | |
| 275 | ||
| 276 | #define emit_branch(BR_OPC, DEST) \ | |
| 277 | do { unsigned int _here = addrs[i] - 8; \ | |
| 278 | *prog++ = BR_OPC | WDISP22((DEST) - _here); \ | |
| 584c5e2a | 279 | } while (0) |
| 2809a208 DM |
280 | |
| 281 | #define emit_branch_off(BR_OPC, OFF) \ | |
| 282 | do { *prog++ = BR_OPC | WDISP22(OFF); \ | |
| 584c5e2a | 283 | } while (0) |
| 2809a208 DM |
284 | |
| 285 | #define emit_jump(DEST) emit_branch(BA, DEST) | |
| 286 | ||
| 584c5e2a DM |
287 | #define emit_read_y(REG) *prog++ = RD_Y | RD(REG) |
| 288 | #define emit_write_y(REG) *prog++ = WR_Y | IMMED | RS1(REG) | S13(0) | |
| 2809a208 DM |
289 | |
| 290 | #define emit_cmp(R1, R2) \ | |
| 291 | *prog++ = (SUBCC | RS1(R1) | RS2(R2) | RD(G0)) | |
| 292 | ||
| 293 | #define emit_cmpi(R1, IMM) \ | |
| 294 | *prog++ = (SUBCC | IMMED | RS1(R1) | S13(IMM) | RD(G0)); | |
| 295 | ||
| 296 | #define emit_btst(R1, R2) \ | |
| 297 | *prog++ = (ANDCC | RS1(R1) | RS2(R2) | RD(G0)) | |
| 298 | ||
| 299 | #define emit_btsti(R1, IMM) \ | |
| 300 | *prog++ = (ANDCC | IMMED | RS1(R1) | S13(IMM) | RD(G0)); | |
| 301 | ||
| 302 | #define emit_sub(R1, R2, R3) \ | |
| 303 | *prog++ = (SUB | RS1(R1) | RS2(R2) | RD(R3)) | |
| 304 | ||
| 305 | #define emit_subi(R1, IMM, R3) \ | |
| 306 | *prog++ = (SUB | IMMED | RS1(R1) | S13(IMM) | RD(R3)) | |
| 307 | ||
| 308 | #define emit_add(R1, R2, R3) \ | |
| 309 | *prog++ = (ADD | RS1(R1) | RS2(R2) | RD(R3)) | |
| 310 | ||
| 311 | #define emit_addi(R1, IMM, R3) \ | |
| 312 | *prog++ = (ADD | IMMED | RS1(R1) | S13(IMM) | RD(R3)) | |
| 313 | ||
| 314 | #define emit_alloc_stack(SZ) \ | |
| 315 | *prog++ = (SUB | IMMED | RS1(SP) | S13(SZ) | RD(SP)) | |
| 316 | ||
| 317 | #define emit_release_stack(SZ) \ | |
| 318 | *prog++ = (ADD | IMMED | RS1(SP) | S13(SZ) | RD(SP)) | |
| 319 | ||
| 584c5e2a DM |
320 | /* A note about branch offset calculations. The addrs[] array, |
| 321 | * indexed by BPF instruction, records the address after all the | |
| 322 | * sparc instructions emitted for that BPF instruction. | |
| 323 | * | |
| 324 | * The most common case is to emit a branch at the end of such | |
| 325 | * a code sequence. So this would be two instructions, the | |
| 326 | * branch and it's delay slot. | |
| 327 | * | |
| 328 | * Therefore by default the branch emitters calculate the branch | |
| 329 | * offset field as: | |
| 330 | * | |
| 331 | * destination - (addrs[i] - 8) | |
| 332 | * | |
| 333 | * This "addrs[i] - 8" is the address of the branch itself or | |
| 334 | * what "." would be in assembler notation. The "8" part is | |
| 335 | * how we take into consideration the branch and it's delay | |
| 336 | * slot mentioned above. | |
| 337 | * | |
| 338 | * Sometimes we need to emit a branch earlier in the code | |
| 339 | * sequence. And in these situations we adjust "destination" | |
| 340 | * to accomodate this difference. For example, if we needed | |
| 341 | * to emit a branch (and it's delay slot) right before the | |
| 342 | * final instruction emitted for a BPF opcode, we'd use | |
| 343 | * "destination + 4" instead of just plain "destination" above. | |
| 344 | * | |
| 345 | * This is why you see all of these funny emit_branch() and | |
| 346 | * emit_jump() calls with adjusted offsets. | |
| 347 | */ | |
| 348 | ||
| 2809a208 DM |
349 | void bpf_jit_compile(struct sk_filter *fp) |
| 350 | { | |
| 351 | unsigned int cleanup_addr, proglen, oldproglen = 0; | |
| 352 | u32 temp[8], *prog, *func, seen = 0, pass; | |
| 353 | const struct sock_filter *filter = fp->insns; | |
| 354 | int i, flen = fp->len, pc_ret0 = -1; | |
| 355 | unsigned int *addrs; | |
| 356 | void *image; | |
| 357 | ||
| 358 | if (!bpf_jit_enable) | |
| 359 | return; | |
| 360 | ||
| 361 | addrs = kmalloc(flen * sizeof(*addrs), GFP_KERNEL); | |
| 362 | if (addrs == NULL) | |
| 363 | return; | |
| 364 | ||
| 365 | /* Before first pass, make a rough estimation of addrs[] | |
| 366 | * each bpf instruction is translated to less than 64 bytes | |
| 367 | */ | |
| 368 | for (proglen = 0, i = 0; i < flen; i++) { | |
| 369 | proglen += 64; | |
| 370 | addrs[i] = proglen; | |
| 371 | } | |
| 372 | cleanup_addr = proglen; /* epilogue address */ | |
| 373 | image = NULL; | |
| 374 | for (pass = 0; pass < 10; pass++) { | |
| 375 | u8 seen_or_pass0 = (pass == 0) ? (SEEN_XREG | SEEN_DATAREF | SEEN_MEM) : seen; | |
| 376 | ||
| 377 | /* no prologue/epilogue for trivial filters (RET something) */ | |
| 378 | proglen = 0; | |
| 379 | prog = temp; | |
| 380 | ||
| 381 | /* Prologue */ | |
| 382 | if (seen_or_pass0) { | |
| 383 | if (seen_or_pass0 & SEEN_MEM) { | |
| 384 | unsigned int sz = BASE_STACKFRAME; | |
| 385 | sz += BPF_MEMWORDS * sizeof(u32); | |
| 386 | emit_alloc_stack(sz); | |
| 387 | } | |
| 388 | ||
| 389 | /* Make sure we dont leek kernel memory. */ | |
| 390 | if (seen_or_pass0 & SEEN_XREG) | |
| 391 | emit_clear(r_X); | |
| 392 | ||
| 393 | /* If this filter needs to access skb data, | |
| 7b56f76e | 394 | * load %o4 and %o5 with: |
| 2809a208 DM |
395 | * %o4 = skb->len - skb->data_len |
| 396 | * %o5 = skb->data | |
| 397 | * And also back up %o7 into r_saved_O7 so we can | |
| 398 | * invoke the stubs using 'call'. | |
| 399 | */ | |
| 400 | if (seen_or_pass0 & SEEN_DATAREF) { | |
| 401 | emit_load32(r_SKB, struct sk_buff, len, r_HEADLEN); | |
| 402 | emit_load32(r_SKB, struct sk_buff, data_len, r_TMP); | |
| 403 | emit_sub(r_HEADLEN, r_TMP, r_HEADLEN); | |
| 404 | emit_loadptr(r_SKB, struct sk_buff, data, r_SKB_DATA); | |
| 405 | } | |
| 406 | } | |
| 407 | emit_reg_move(O7, r_saved_O7); | |
| 408 | ||
| 409 | switch (filter[0].code) { | |
| 410 | case BPF_S_RET_K: | |
| 411 | case BPF_S_LD_W_LEN: | |
| 412 | case BPF_S_ANC_PROTOCOL: | |
| 413 | case BPF_S_ANC_PKTTYPE: | |
| 414 | case BPF_S_ANC_IFINDEX: | |
| 415 | case BPF_S_ANC_MARK: | |
| 416 | case BPF_S_ANC_RXHASH: | |
| 417 | case BPF_S_ANC_CPU: | |
| 418 | case BPF_S_ANC_QUEUE: | |
| 419 | case BPF_S_LD_W_ABS: | |
| 420 | case BPF_S_LD_H_ABS: | |
| 421 | case BPF_S_LD_B_ABS: | |
| 422 | /* The first instruction sets the A register (or is | |
| 423 | * a "RET 'constant'") | |
| 424 | */ | |
| 425 | break; | |
| 426 | default: | |
| 427 | /* Make sure we dont leak kernel information to the | |
| 428 | * user. | |
| 429 | */ | |
| 430 | emit_clear(r_A); /* A = 0 */ | |
| 431 | } | |
| 432 | ||
| 433 | for (i = 0; i < flen; i++) { | |
| 434 | unsigned int K = filter[i].k; | |
| 435 | unsigned int t_offset; | |
| 436 | unsigned int f_offset; | |
| 437 | u32 t_op, f_op; | |
| 438 | int ilen; | |
| 439 | ||
| 440 | switch (filter[i].code) { | |
| 441 | case BPF_S_ALU_ADD_X: /* A += X; */ | |
| 442 | emit_alu_X(ADD); | |
| 443 | break; | |
| 444 | case BPF_S_ALU_ADD_K: /* A += K; */ | |
| 445 | emit_alu_K(ADD, K); | |
| 446 | break; | |
| 447 | case BPF_S_ALU_SUB_X: /* A -= X; */ | |
| 448 | emit_alu_X(SUB); | |
| 449 | break; | |
| 450 | case BPF_S_ALU_SUB_K: /* A -= K */ | |
| 451 | emit_alu_K(SUB, K); | |
| 452 | break; | |
| 453 | case BPF_S_ALU_AND_X: /* A &= X */ | |
| 454 | emit_alu_X(AND); | |
| 455 | break; | |
| 456 | case BPF_S_ALU_AND_K: /* A &= K */ | |
| 457 | emit_alu_K(AND, K); | |
| 458 | break; | |
| 459 | case BPF_S_ALU_OR_X: /* A |= X */ | |
| 460 | emit_alu_X(OR); | |
| 461 | break; | |
| 462 | case BPF_S_ALU_OR_K: /* A |= K */ | |
| 463 | emit_alu_K(OR, K); | |
| 464 | break; | |
| 465 | case BPF_S_ALU_LSH_X: /* A <<= X */ | |
| 466 | emit_alu_X(SLL); | |
| 467 | break; | |
| 468 | case BPF_S_ALU_LSH_K: /* A <<= K */ | |
| 469 | emit_alu_K(SLL, K); | |
| 470 | break; | |
| 471 | case BPF_S_ALU_RSH_X: /* A >>= X */ | |
| 472 | emit_alu_X(SRL); | |
| 473 | break; | |
| 474 | case BPF_S_ALU_RSH_K: /* A >>= K */ | |
| 475 | emit_alu_K(SRL, K); | |
| 476 | break; | |
| 477 | case BPF_S_ALU_MUL_X: /* A *= X; */ | |
| 478 | emit_alu_X(MUL); | |
| 479 | break; | |
| 480 | case BPF_S_ALU_MUL_K: /* A *= K */ | |
| 481 | emit_alu_K(MUL, K); | |
| 482 | break; | |
| 483 | case BPF_S_ALU_DIV_K: /* A /= K */ | |
| 484 | emit_alu_K(MUL, K); | |
| 485 | emit_read_y(r_A); | |
| 486 | break; | |
| 487 | case BPF_S_ALU_DIV_X: /* A /= X; */ | |
| 488 | emit_cmpi(r_X, 0); | |
| 489 | if (pc_ret0 > 0) { | |
| 490 | t_offset = addrs[pc_ret0 - 1]; | |
| 491 | #ifdef CONFIG_SPARC32 | |
| 492 | emit_branch(BE, t_offset + 20); | |
| 493 | #else | |
| 494 | emit_branch(BE, t_offset + 8); | |
| 495 | #endif | |
| 496 | emit_nop(); /* delay slot */ | |
| 497 | } else { | |
| 498 | emit_branch_off(BNE, 16); | |
| 499 | emit_nop(); | |
| 500 | #ifdef CONFIG_SPARC32 | |
| 501 | emit_jump(cleanup_addr + 20); | |
| 502 | #else | |
| 503 | emit_jump(cleanup_addr + 8); | |
| 504 | #endif | |
| 505 | emit_clear(r_A); | |
| 506 | } | |
| 507 | emit_write_y(G0); | |
| 508 | #ifdef CONFIG_SPARC32 | |
| 584c5e2a DM |
509 | /* The Sparc v8 architecture requires |
| 510 | * three instructions between a %y | |
| 511 | * register write and the first use. | |
| 512 | */ | |
| 2809a208 DM |
513 | emit_nop(); |
| 514 | emit_nop(); | |
| 515 | emit_nop(); | |
| 516 | #endif | |
| 517 | emit_alu_X(DIV); | |
| 518 | break; | |
| 519 | case BPF_S_ALU_NEG: | |
| 520 | emit_neg(); | |
| 521 | break; | |
| 522 | case BPF_S_RET_K: | |
| 523 | if (!K) { | |
| 524 | if (pc_ret0 == -1) | |
| 525 | pc_ret0 = i; | |
| 526 | emit_clear(r_A); | |
| 527 | } else { | |
| 528 | emit_loadimm(K, r_A); | |
| 529 | } | |
| 530 | /* Fallthrough */ | |
| 531 | case BPF_S_RET_A: | |
| 532 | if (seen_or_pass0) { | |
| 533 | if (i != flen - 1) { | |
| 534 | emit_jump(cleanup_addr); | |
| 535 | emit_nop(); | |
| 536 | break; | |
| 537 | } | |
| 538 | if (seen_or_pass0 & SEEN_MEM) { | |
| 539 | unsigned int sz = BASE_STACKFRAME; | |
| 540 | sz += BPF_MEMWORDS * sizeof(u32); | |
| 541 | emit_release_stack(sz); | |
| 542 | } | |
| 543 | } | |
| 544 | /* jmpl %r_saved_O7 + 8, %g0 */ | |
| 545 | emit_jmpl(r_saved_O7, 8, G0); | |
| 546 | emit_reg_move(r_A, O0); /* delay slot */ | |
| 547 | break; | |
| 548 | case BPF_S_MISC_TAX: | |
| 549 | seen |= SEEN_XREG; | |
| 550 | emit_reg_move(r_A, r_X); | |
| 551 | break; | |
| 552 | case BPF_S_MISC_TXA: | |
| 553 | seen |= SEEN_XREG; | |
| 554 | emit_reg_move(r_X, r_A); | |
| 555 | break; | |
| 556 | case BPF_S_ANC_CPU: | |
| 557 | emit_load_cpu(r_A); | |
| 558 | break; | |
| 559 | case BPF_S_ANC_PROTOCOL: | |
| 560 | emit_skb_load16(protocol, r_A); | |
| 561 | break; | |
| 562 | #if 0 | |
| 563 | /* GCC won't let us take the address of | |
| 564 | * a bit field even though we very much | |
| 565 | * know what we are doing here. | |
| 566 | */ | |
| 567 | case BPF_S_ANC_PKTTYPE: | |
| 568 | __emit_skb_load8(pkt_type, r_A); | |
| 569 | emit_alu_K(SRL, 5); | |
| 570 | break; | |
| 571 | #endif | |
| 572 | case BPF_S_ANC_IFINDEX: | |
| 573 | emit_skb_loadptr(dev, r_A); | |
| 574 | emit_cmpi(r_A, 0); | |
| 575 | emit_branch(BNE_PTR, cleanup_addr + 4); | |
| 576 | emit_nop(); | |
| 577 | emit_load32(r_A, struct net_device, ifindex, r_A); | |
| 578 | break; | |
| 579 | case BPF_S_ANC_MARK: | |
| 580 | emit_skb_load32(mark, r_A); | |
| 581 | break; | |
| 582 | case BPF_S_ANC_QUEUE: | |
| 583 | emit_skb_load16(queue_mapping, r_A); | |
| 584 | break; | |
| 585 | case BPF_S_ANC_HATYPE: | |
| 586 | emit_skb_loadptr(dev, r_A); | |
| 587 | emit_cmpi(r_A, 0); | |
| 588 | emit_branch(BNE_PTR, cleanup_addr + 4); | |
| 589 | emit_nop(); | |
| 590 | emit_load16(r_A, struct net_device, type, r_A); | |
| 591 | break; | |
| 592 | case BPF_S_ANC_RXHASH: | |
| 593 | emit_skb_load32(rxhash, r_A); | |
| 594 | break; | |
| 595 | ||
| 596 | case BPF_S_LD_IMM: | |
| 597 | emit_loadimm(K, r_A); | |
| 598 | break; | |
| 599 | case BPF_S_LDX_IMM: | |
| 600 | emit_loadimm(K, r_X); | |
| 601 | break; | |
| 602 | case BPF_S_LD_MEM: | |
| 603 | emit_ldmem(K * 4, r_A); | |
| 604 | break; | |
| 605 | case BPF_S_LDX_MEM: | |
| 606 | emit_ldmem(K * 4, r_X); | |
| 607 | break; | |
| 608 | case BPF_S_ST: | |
| 609 | emit_stmem(K * 4, r_A); | |
| 610 | break; | |
| 611 | case BPF_S_STX: | |
| 612 | emit_stmem(K * 4, r_X); | |
| 613 | break; | |
| 614 | ||
| 615 | #define CHOOSE_LOAD_FUNC(K, func) \ | |
| 616 | ((int)K < 0 ? ((int)K >= SKF_LL_OFF ? func##_negative_offset : func) : func##_positive_offset) | |
| 617 | ||
| 618 | case BPF_S_LD_W_ABS: | |
| 619 | func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_word); | |
| 620 | common_load: seen |= SEEN_DATAREF; | |
| 621 | emit_loadimm(K, r_OFF); | |
| 622 | emit_call(func); | |
| 623 | break; | |
| 624 | case BPF_S_LD_H_ABS: | |
| 625 | func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_half); | |
| 626 | goto common_load; | |
| 627 | case BPF_S_LD_B_ABS: | |
| 628 | func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_byte); | |
| 629 | goto common_load; | |
| 630 | case BPF_S_LDX_B_MSH: | |
| 631 | func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_byte_msh); | |
| 632 | goto common_load; | |
| 633 | case BPF_S_LD_W_IND: | |
| 634 | func = bpf_jit_load_word; | |
| 635 | common_load_ind: seen |= SEEN_DATAREF | SEEN_XREG; | |
| 636 | if (K) { | |
| 637 | if (is_simm13(K)) { | |
| 638 | emit_addi(r_X, K, r_OFF); | |
| 639 | } else { | |
| 640 | emit_loadimm(K, r_TMP); | |
| 641 | emit_add(r_X, r_TMP, r_OFF); | |
| 642 | } | |
| 643 | } else { | |
| 644 | emit_reg_move(r_X, r_OFF); | |
| 645 | } | |
| 646 | emit_call(func); | |
| 647 | break; | |
| 648 | case BPF_S_LD_H_IND: | |
| 649 | func = bpf_jit_load_half; | |
| 650 | goto common_load_ind; | |
| 651 | case BPF_S_LD_B_IND: | |
| 652 | func = bpf_jit_load_byte; | |
| 653 | goto common_load_ind; | |
| 654 | case BPF_S_JMP_JA: | |
| 655 | emit_jump(addrs[i + K]); | |
| 656 | emit_nop(); | |
| 657 | break; | |
| 658 | ||
| 659 | #define COND_SEL(CODE, TOP, FOP) \ | |
| 660 | case CODE: \ | |
| 661 | t_op = TOP; \ | |
| 662 | f_op = FOP; \ | |
| 663 | goto cond_branch | |
| 664 | ||
| 665 | COND_SEL(BPF_S_JMP_JGT_K, BGU, BLEU); | |
| 666 | COND_SEL(BPF_S_JMP_JGE_K, BGEU, BLU); | |
| 667 | COND_SEL(BPF_S_JMP_JEQ_K, BE, BNE); | |
| 668 | COND_SEL(BPF_S_JMP_JSET_K, BNE, BE); | |
| 669 | COND_SEL(BPF_S_JMP_JGT_X, BGU, BLEU); | |
| 670 | COND_SEL(BPF_S_JMP_JGE_X, BGEU, BLU); | |
| 671 | COND_SEL(BPF_S_JMP_JEQ_X, BE, BNE); | |
| 672 | COND_SEL(BPF_S_JMP_JSET_X, BNE, BE); | |
| 673 | ||
| 674 | cond_branch: f_offset = addrs[i + filter[i].jf]; | |
| 675 | t_offset = addrs[i + filter[i].jt]; | |
| 676 | ||
| 677 | /* same targets, can avoid doing the test :) */ | |
| 678 | if (filter[i].jt == filter[i].jf) { | |
| 679 | emit_jump(t_offset); | |
| 680 | emit_nop(); | |
| 681 | break; | |
| 682 | } | |
| 683 | ||
| 684 | switch (filter[i].code) { | |
| 685 | case BPF_S_JMP_JGT_X: | |
| 686 | case BPF_S_JMP_JGE_X: | |
| 687 | case BPF_S_JMP_JEQ_X: | |
| 688 | seen |= SEEN_XREG; | |
| 689 | emit_cmp(r_A, r_X); | |
| 690 | break; | |
| 691 | case BPF_S_JMP_JSET_X: | |
| 692 | seen |= SEEN_XREG; | |
| 693 | emit_btst(r_A, r_X); | |
| 694 | break; | |
| 695 | case BPF_S_JMP_JEQ_K: | |
| 696 | case BPF_S_JMP_JGT_K: | |
| 697 | case BPF_S_JMP_JGE_K: | |
| 698 | if (is_simm13(K)) { | |
| 699 | emit_cmpi(r_A, K); | |
| 700 | } else { | |
| 701 | emit_loadimm(K, r_TMP); | |
| 702 | emit_cmp(r_A, r_TMP); | |
| 703 | } | |
| 704 | break; | |
| 705 | case BPF_S_JMP_JSET_K: | |
| 706 | if (is_simm13(K)) { | |
| 707 | emit_btsti(r_A, K); | |
| 708 | } else { | |
| 709 | emit_loadimm(K, r_TMP); | |
| 710 | emit_btst(r_A, r_TMP); | |
| 711 | } | |
| 712 | break; | |
| 713 | } | |
| 714 | if (filter[i].jt != 0) { | |
| 715 | if (filter[i].jf) | |
| 716 | t_offset += 8; | |
| 717 | emit_branch(t_op, t_offset); | |
| 718 | emit_nop(); /* delay slot */ | |
| 719 | if (filter[i].jf) { | |
| 720 | emit_jump(f_offset); | |
| 721 | emit_nop(); | |
| 722 | } | |
| 723 | break; | |
| 724 | } | |
| 725 | emit_branch(f_op, f_offset); | |
| 726 | emit_nop(); /* delay slot */ | |
| 727 | break; | |
| 728 | ||
| 729 | default: | |
| 730 | /* hmm, too complex filter, give up with jit compiler */ | |
| 731 | goto out; | |
| 732 | } | |
| 733 | ilen = (void *) prog - (void *) temp; | |
| 734 | if (image) { | |
| 735 | if (unlikely(proglen + ilen > oldproglen)) { | |
| 736 | pr_err("bpb_jit_compile fatal error\n"); | |
| 737 | kfree(addrs); | |
| 738 | module_free(NULL, image); | |
| 739 | return; | |
| 740 | } | |
| 741 | memcpy(image + proglen, temp, ilen); | |
| 742 | } | |
| 743 | proglen += ilen; | |
| 744 | addrs[i] = proglen; | |
| 745 | prog = temp; | |
| 746 | } | |
| 747 | /* last bpf instruction is always a RET : | |
| 748 | * use it to give the cleanup instruction(s) addr | |
| 749 | */ | |
| 750 | cleanup_addr = proglen - 8; /* jmpl; mov r_A,%o0; */ | |
| 751 | if (seen_or_pass0 & SEEN_MEM) | |
| 752 | cleanup_addr -= 4; /* add %sp, X, %sp; */ | |
| 753 | ||
| 754 | if (image) { | |
| 755 | if (proglen != oldproglen) | |
| 756 | pr_err("bpb_jit_compile proglen=%u != oldproglen=%u\n", | |
| 757 | proglen, oldproglen); | |
| 758 | break; | |
| 759 | } | |
| 760 | if (proglen == oldproglen) { | |
| 761 | image = module_alloc(max_t(unsigned int, | |
| 762 | proglen, | |
| 763 | sizeof(struct work_struct))); | |
| 764 | if (!image) | |
| 765 | goto out; | |
| 766 | } | |
| 767 | oldproglen = proglen; | |
| 768 | } | |
| 769 | ||
| 770 | if (bpf_jit_enable > 1) | |
| 771 | pr_err("flen=%d proglen=%u pass=%d image=%p\n", | |
| 772 | flen, proglen, pass, image); | |
| 773 | ||
| 774 | if (image) { | |
| 775 | if (bpf_jit_enable > 1) | |
| 776 | print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_ADDRESS, | |
| 777 | 16, 1, image, proglen, false); | |
| 778 | bpf_flush_icache(image, image + proglen); | |
| 779 | fp->bpf_func = (void *)image; | |
| 780 | } | |
| 781 | out: | |
| 782 | kfree(addrs); | |
| 783 | return; | |
| 784 | } | |
| 785 | ||
| 786 | static void jit_free_defer(struct work_struct *arg) | |
| 787 | { | |
| 788 | module_free(NULL, arg); | |
| 789 | } | |
| 790 | ||
| 791 | /* run from softirq, we must use a work_struct to call | |
| 792 | * module_free() from process context | |
| 793 | */ | |
| 794 | void bpf_jit_free(struct sk_filter *fp) | |
| 795 | { | |
| 796 | if (fp->bpf_func != sk_run_filter) { | |
| 797 | struct work_struct *work = (struct work_struct *)fp->bpf_func; | |
| 798 | ||
| 799 | INIT_WORK(work, jit_free_defer); | |
| 800 | schedule_work(work); | |
| 801 | } | |
| 802 | } |