David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 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> |
Daniel Borkmann | 54e7e2d | 2012-11-04 16:59:30 +0000 | [diff] [blame] | 6 | #include <linux/if_vlan.h> |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 7 | |
| 8 | #include <asm/cacheflush.h> |
| 9 | #include <asm/ptrace.h> |
| 10 | |
| 11 | #include "bpf_jit.h" |
| 12 | |
| 13 | int bpf_jit_enable __read_mostly; |
| 14 | |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 15 | static inline bool is_simm13(unsigned int value) |
| 16 | { |
| 17 | return value + 0x1000 < 0x2000; |
| 18 | } |
| 19 | |
| 20 | static void bpf_flush_icache(void *start_, void *end_) |
| 21 | { |
| 22 | #ifdef CONFIG_SPARC64 |
| 23 | /* Cheetah's I-cache is fully coherent. */ |
| 24 | if (tlb_type == spitfire) { |
| 25 | unsigned long start = (unsigned long) start_; |
| 26 | unsigned long end = (unsigned long) end_; |
| 27 | |
| 28 | start &= ~7UL; |
| 29 | end = (end + 7UL) & ~7UL; |
| 30 | while (start < end) { |
| 31 | flushi(start); |
| 32 | start += 32; |
| 33 | } |
| 34 | } |
| 35 | #endif |
| 36 | } |
| 37 | |
| 38 | #define SEEN_DATAREF 1 /* might call external helpers */ |
| 39 | #define SEEN_XREG 2 /* ebx is used */ |
| 40 | #define SEEN_MEM 4 /* use mem[] for temporary storage */ |
| 41 | |
| 42 | #define S13(X) ((X) & 0x1fff) |
| 43 | #define IMMED 0x00002000 |
| 44 | #define RD(X) ((X) << 25) |
| 45 | #define RS1(X) ((X) << 14) |
| 46 | #define RS2(X) ((X)) |
| 47 | #define OP(X) ((X) << 30) |
| 48 | #define OP2(X) ((X) << 22) |
| 49 | #define OP3(X) ((X) << 19) |
| 50 | #define COND(X) ((X) << 25) |
| 51 | #define F1(X) OP(X) |
| 52 | #define F2(X, Y) (OP(X) | OP2(Y)) |
| 53 | #define F3(X, Y) (OP(X) | OP3(Y)) |
| 54 | |
David S. Miller | 584c5e2 | 2012-04-17 16:38:16 -0400 | [diff] [blame] | 55 | #define CONDN COND(0x0) |
| 56 | #define CONDE COND(0x1) |
| 57 | #define CONDLE COND(0x2) |
| 58 | #define CONDL COND(0x3) |
| 59 | #define CONDLEU COND(0x4) |
| 60 | #define CONDCS COND(0x5) |
| 61 | #define CONDNEG COND(0x6) |
| 62 | #define CONDVC COND(0x7) |
| 63 | #define CONDA COND(0x8) |
| 64 | #define CONDNE COND(0x9) |
| 65 | #define CONDG COND(0xa) |
| 66 | #define CONDGE COND(0xb) |
| 67 | #define CONDGU COND(0xc) |
| 68 | #define CONDCC COND(0xd) |
| 69 | #define CONDPOS COND(0xe) |
| 70 | #define CONDVS COND(0xf) |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 71 | |
| 72 | #define CONDGEU CONDCC |
| 73 | #define CONDLU CONDCS |
| 74 | |
| 75 | #define WDISP22(X) (((X) >> 2) & 0x3fffff) |
| 76 | |
| 77 | #define BA (F2(0, 2) | CONDA) |
| 78 | #define BGU (F2(0, 2) | CONDGU) |
| 79 | #define BLEU (F2(0, 2) | CONDLEU) |
| 80 | #define BGEU (F2(0, 2) | CONDGEU) |
| 81 | #define BLU (F2(0, 2) | CONDLU) |
| 82 | #define BE (F2(0, 2) | CONDE) |
| 83 | #define BNE (F2(0, 2) | CONDNE) |
| 84 | |
| 85 | #ifdef CONFIG_SPARC64 |
| 86 | #define BNE_PTR (F2(0, 1) | CONDNE | (2 << 20)) |
| 87 | #else |
| 88 | #define BNE_PTR BNE |
| 89 | #endif |
| 90 | |
| 91 | #define SETHI(K, REG) \ |
| 92 | (F2(0, 0x4) | RD(REG) | (((K) >> 10) & 0x3fffff)) |
| 93 | #define OR_LO(K, REG) \ |
| 94 | (F3(2, 0x02) | IMMED | RS1(REG) | ((K) & 0x3ff) | RD(REG)) |
| 95 | |
| 96 | #define ADD F3(2, 0x00) |
| 97 | #define AND F3(2, 0x01) |
| 98 | #define ANDCC F3(2, 0x11) |
| 99 | #define OR F3(2, 0x02) |
David S. Miller | d7ce8a5 | 2012-06-06 10:20:21 -0700 | [diff] [blame] | 100 | #define XOR F3(2, 0x03) |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 101 | #define SUB F3(2, 0x04) |
| 102 | #define SUBCC F3(2, 0x14) |
| 103 | #define MUL F3(2, 0x0a) /* umul */ |
| 104 | #define DIV F3(2, 0x0e) /* udiv */ |
| 105 | #define SLL F3(2, 0x25) |
| 106 | #define SRL F3(2, 0x26) |
| 107 | #define JMPL F3(2, 0x38) |
| 108 | #define CALL F1(1) |
| 109 | #define BR F2(0, 0x01) |
| 110 | #define RD_Y F3(2, 0x28) |
| 111 | #define WR_Y F3(2, 0x30) |
| 112 | |
| 113 | #define LD32 F3(3, 0x00) |
| 114 | #define LD8 F3(3, 0x01) |
| 115 | #define LD16 F3(3, 0x02) |
| 116 | #define LD64 F3(3, 0x0b) |
| 117 | #define ST32 F3(3, 0x04) |
| 118 | |
| 119 | #ifdef CONFIG_SPARC64 |
| 120 | #define LDPTR LD64 |
| 121 | #define BASE_STACKFRAME 176 |
| 122 | #else |
| 123 | #define LDPTR LD32 |
| 124 | #define BASE_STACKFRAME 96 |
| 125 | #endif |
| 126 | |
| 127 | #define LD32I (LD32 | IMMED) |
| 128 | #define LD8I (LD8 | IMMED) |
| 129 | #define LD16I (LD16 | IMMED) |
| 130 | #define LD64I (LD64 | IMMED) |
| 131 | #define LDPTRI (LDPTR | IMMED) |
| 132 | #define ST32I (ST32 | IMMED) |
| 133 | |
| 134 | #define emit_nop() \ |
| 135 | do { \ |
| 136 | *prog++ = SETHI(0, G0); \ |
| 137 | } while (0) |
| 138 | |
| 139 | #define emit_neg() \ |
| 140 | do { /* sub %g0, r_A, r_A */ \ |
| 141 | *prog++ = SUB | RS1(G0) | RS2(r_A) | RD(r_A); \ |
| 142 | } while (0) |
| 143 | |
| 144 | #define emit_reg_move(FROM, TO) \ |
| 145 | do { /* or %g0, FROM, TO */ \ |
| 146 | *prog++ = OR | RS1(G0) | RS2(FROM) | RD(TO); \ |
| 147 | } while (0) |
| 148 | |
| 149 | #define emit_clear(REG) \ |
| 150 | do { /* or %g0, %g0, REG */ \ |
| 151 | *prog++ = OR | RS1(G0) | RS2(G0) | RD(REG); \ |
| 152 | } while (0) |
| 153 | |
| 154 | #define emit_set_const(K, REG) \ |
| 155 | do { /* sethi %hi(K), REG */ \ |
| 156 | *prog++ = SETHI(K, REG); \ |
| 157 | /* or REG, %lo(K), REG */ \ |
| 158 | *prog++ = OR_LO(K, REG); \ |
| 159 | } while (0) |
| 160 | |
| 161 | /* Emit |
| 162 | * |
David S. Miller | 584c5e2 | 2012-04-17 16:38:16 -0400 | [diff] [blame] | 163 | * OP r_A, r_X, r_A |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 164 | */ |
| 165 | #define emit_alu_X(OPCODE) \ |
| 166 | do { \ |
| 167 | seen |= SEEN_XREG; \ |
| 168 | *prog++ = OPCODE | RS1(r_A) | RS2(r_X) | RD(r_A); \ |
| 169 | } while (0) |
| 170 | |
| 171 | /* Emit either: |
| 172 | * |
| 173 | * OP r_A, K, r_A |
| 174 | * |
| 175 | * or |
| 176 | * |
| 177 | * sethi %hi(K), r_TMP |
| 178 | * or r_TMP, %lo(K), r_TMP |
| 179 | * OP r_A, r_TMP, r_A |
| 180 | * |
| 181 | * depending upon whether K fits in a signed 13-bit |
| 182 | * immediate instruction field. Emit nothing if K |
| 183 | * is zero. |
| 184 | */ |
| 185 | #define emit_alu_K(OPCODE, K) \ |
David S. Miller | 584c5e2 | 2012-04-17 16:38:16 -0400 | [diff] [blame] | 186 | do { \ |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 187 | if (K) { \ |
| 188 | unsigned int _insn = OPCODE; \ |
| 189 | _insn |= RS1(r_A) | RD(r_A); \ |
| 190 | if (is_simm13(K)) { \ |
| 191 | *prog++ = _insn | IMMED | S13(K); \ |
| 192 | } else { \ |
| 193 | emit_set_const(K, r_TMP); \ |
| 194 | *prog++ = _insn | RS2(r_TMP); \ |
David S. Miller | 584c5e2 | 2012-04-17 16:38:16 -0400 | [diff] [blame] | 195 | } \ |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 196 | } \ |
| 197 | } while (0) |
| 198 | |
| 199 | #define emit_loadimm(K, DEST) \ |
| 200 | do { \ |
| 201 | if (is_simm13(K)) { \ |
| 202 | /* or %g0, K, DEST */ \ |
| 203 | *prog++ = OR | IMMED | RS1(G0) | S13(K) | RD(DEST); \ |
| 204 | } else { \ |
| 205 | emit_set_const(K, DEST); \ |
| 206 | } \ |
| 207 | } while (0) |
| 208 | |
| 209 | #define emit_loadptr(BASE, STRUCT, FIELD, DEST) \ |
| 210 | do { unsigned int _off = offsetof(STRUCT, FIELD); \ |
| 211 | BUILD_BUG_ON(FIELD_SIZEOF(STRUCT, FIELD) != sizeof(void *)); \ |
| 212 | *prog++ = LDPTRI | RS1(BASE) | S13(_off) | RD(DEST); \ |
David S. Miller | 584c5e2 | 2012-04-17 16:38:16 -0400 | [diff] [blame] | 213 | } while (0) |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 214 | |
| 215 | #define emit_load32(BASE, STRUCT, FIELD, DEST) \ |
| 216 | do { unsigned int _off = offsetof(STRUCT, FIELD); \ |
| 217 | BUILD_BUG_ON(FIELD_SIZEOF(STRUCT, FIELD) != sizeof(u32)); \ |
| 218 | *prog++ = LD32I | RS1(BASE) | S13(_off) | RD(DEST); \ |
David S. Miller | 584c5e2 | 2012-04-17 16:38:16 -0400 | [diff] [blame] | 219 | } while (0) |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 220 | |
| 221 | #define emit_load16(BASE, STRUCT, FIELD, DEST) \ |
| 222 | do { unsigned int _off = offsetof(STRUCT, FIELD); \ |
| 223 | BUILD_BUG_ON(FIELD_SIZEOF(STRUCT, FIELD) != sizeof(u16)); \ |
| 224 | *prog++ = LD16I | RS1(BASE) | S13(_off) | RD(DEST); \ |
David S. Miller | 584c5e2 | 2012-04-17 16:38:16 -0400 | [diff] [blame] | 225 | } while (0) |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 226 | |
| 227 | #define __emit_load8(BASE, STRUCT, FIELD, DEST) \ |
| 228 | do { unsigned int _off = offsetof(STRUCT, FIELD); \ |
| 229 | *prog++ = LD8I | RS1(BASE) | S13(_off) | RD(DEST); \ |
David S. Miller | 584c5e2 | 2012-04-17 16:38:16 -0400 | [diff] [blame] | 230 | } while (0) |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 231 | |
| 232 | #define emit_load8(BASE, STRUCT, FIELD, DEST) \ |
| 233 | do { BUILD_BUG_ON(FIELD_SIZEOF(STRUCT, FIELD) != sizeof(u8)); \ |
| 234 | __emit_load8(BASE, STRUCT, FIELD, DEST); \ |
David S. Miller | 584c5e2 | 2012-04-17 16:38:16 -0400 | [diff] [blame] | 235 | } while (0) |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 236 | |
| 237 | #define emit_ldmem(OFF, DEST) \ |
| 238 | do { *prog++ = LD32I | RS1(FP) | S13(-(OFF)) | RD(DEST); \ |
David S. Miller | 584c5e2 | 2012-04-17 16:38:16 -0400 | [diff] [blame] | 239 | } while (0) |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 240 | |
| 241 | #define emit_stmem(OFF, SRC) \ |
| 242 | do { *prog++ = LD32I | RS1(FP) | S13(-(OFF)) | RD(SRC); \ |
David S. Miller | 584c5e2 | 2012-04-17 16:38:16 -0400 | [diff] [blame] | 243 | } while (0) |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 244 | |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 245 | #ifdef CONFIG_SMP |
| 246 | #ifdef CONFIG_SPARC64 |
| 247 | #define emit_load_cpu(REG) \ |
| 248 | emit_load16(G6, struct thread_info, cpu, REG) |
| 249 | #else |
| 250 | #define emit_load_cpu(REG) \ |
| 251 | emit_load32(G6, struct thread_info, cpu, REG) |
| 252 | #endif |
| 253 | #else |
| 254 | #define emit_load_cpu(REG) emit_clear(REG) |
| 255 | #endif |
| 256 | |
| 257 | #define emit_skb_loadptr(FIELD, DEST) \ |
| 258 | emit_loadptr(r_SKB, struct sk_buff, FIELD, DEST) |
| 259 | #define emit_skb_load32(FIELD, DEST) \ |
| 260 | emit_load32(r_SKB, struct sk_buff, FIELD, DEST) |
| 261 | #define emit_skb_load16(FIELD, DEST) \ |
| 262 | emit_load16(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 | #define emit_skb_load8(FIELD, DEST) \ |
| 266 | emit_load8(r_SKB, struct sk_buff, FIELD, DEST) |
| 267 | |
| 268 | #define emit_jmpl(BASE, IMM_OFF, LREG) \ |
| 269 | *prog++ = (JMPL | IMMED | RS1(BASE) | S13(IMM_OFF) | RD(LREG)) |
| 270 | |
| 271 | #define emit_call(FUNC) \ |
| 272 | do { void *_here = image + addrs[i] - 8; \ |
| 273 | unsigned int _off = (void *)(FUNC) - _here; \ |
| 274 | *prog++ = CALL | (((_off) >> 2) & 0x3fffffff); \ |
| 275 | emit_nop(); \ |
| 276 | } while (0) |
| 277 | |
| 278 | #define emit_branch(BR_OPC, DEST) \ |
| 279 | do { unsigned int _here = addrs[i] - 8; \ |
| 280 | *prog++ = BR_OPC | WDISP22((DEST) - _here); \ |
David S. Miller | 584c5e2 | 2012-04-17 16:38:16 -0400 | [diff] [blame] | 281 | } while (0) |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 282 | |
| 283 | #define emit_branch_off(BR_OPC, OFF) \ |
| 284 | do { *prog++ = BR_OPC | WDISP22(OFF); \ |
David S. Miller | 584c5e2 | 2012-04-17 16:38:16 -0400 | [diff] [blame] | 285 | } while (0) |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 286 | |
| 287 | #define emit_jump(DEST) emit_branch(BA, DEST) |
| 288 | |
David S. Miller | 584c5e2 | 2012-04-17 16:38:16 -0400 | [diff] [blame] | 289 | #define emit_read_y(REG) *prog++ = RD_Y | RD(REG) |
| 290 | #define emit_write_y(REG) *prog++ = WR_Y | IMMED | RS1(REG) | S13(0) |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 291 | |
| 292 | #define emit_cmp(R1, R2) \ |
| 293 | *prog++ = (SUBCC | RS1(R1) | RS2(R2) | RD(G0)) |
| 294 | |
| 295 | #define emit_cmpi(R1, IMM) \ |
| 296 | *prog++ = (SUBCC | IMMED | RS1(R1) | S13(IMM) | RD(G0)); |
| 297 | |
| 298 | #define emit_btst(R1, R2) \ |
| 299 | *prog++ = (ANDCC | RS1(R1) | RS2(R2) | RD(G0)) |
| 300 | |
| 301 | #define emit_btsti(R1, IMM) \ |
| 302 | *prog++ = (ANDCC | IMMED | RS1(R1) | S13(IMM) | RD(G0)); |
| 303 | |
| 304 | #define emit_sub(R1, R2, R3) \ |
| 305 | *prog++ = (SUB | RS1(R1) | RS2(R2) | RD(R3)) |
| 306 | |
| 307 | #define emit_subi(R1, IMM, R3) \ |
| 308 | *prog++ = (SUB | IMMED | RS1(R1) | S13(IMM) | RD(R3)) |
| 309 | |
| 310 | #define emit_add(R1, R2, R3) \ |
| 311 | *prog++ = (ADD | RS1(R1) | RS2(R2) | RD(R3)) |
| 312 | |
| 313 | #define emit_addi(R1, IMM, R3) \ |
| 314 | *prog++ = (ADD | IMMED | RS1(R1) | S13(IMM) | RD(R3)) |
| 315 | |
Daniel Borkmann | 54e7e2d | 2012-11-04 16:59:30 +0000 | [diff] [blame] | 316 | #define emit_and(R1, R2, R3) \ |
| 317 | *prog++ = (AND | RS1(R1) | RS2(R2) | RD(R3)) |
| 318 | |
| 319 | #define emit_andi(R1, IMM, R3) \ |
| 320 | *prog++ = (AND | IMMED | RS1(R1) | S13(IMM) | RD(R3)) |
| 321 | |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 322 | #define emit_alloc_stack(SZ) \ |
| 323 | *prog++ = (SUB | IMMED | RS1(SP) | S13(SZ) | RD(SP)) |
| 324 | |
| 325 | #define emit_release_stack(SZ) \ |
| 326 | *prog++ = (ADD | IMMED | RS1(SP) | S13(SZ) | RD(SP)) |
| 327 | |
David S. Miller | 584c5e2 | 2012-04-17 16:38:16 -0400 | [diff] [blame] | 328 | /* A note about branch offset calculations. The addrs[] array, |
| 329 | * indexed by BPF instruction, records the address after all the |
| 330 | * sparc instructions emitted for that BPF instruction. |
| 331 | * |
| 332 | * The most common case is to emit a branch at the end of such |
| 333 | * a code sequence. So this would be two instructions, the |
| 334 | * branch and it's delay slot. |
| 335 | * |
| 336 | * Therefore by default the branch emitters calculate the branch |
| 337 | * offset field as: |
| 338 | * |
| 339 | * destination - (addrs[i] - 8) |
| 340 | * |
| 341 | * This "addrs[i] - 8" is the address of the branch itself or |
| 342 | * what "." would be in assembler notation. The "8" part is |
| 343 | * how we take into consideration the branch and it's delay |
| 344 | * slot mentioned above. |
| 345 | * |
| 346 | * Sometimes we need to emit a branch earlier in the code |
| 347 | * sequence. And in these situations we adjust "destination" |
| 348 | * to accomodate this difference. For example, if we needed |
| 349 | * to emit a branch (and it's delay slot) right before the |
| 350 | * final instruction emitted for a BPF opcode, we'd use |
| 351 | * "destination + 4" instead of just plain "destination" above. |
| 352 | * |
| 353 | * This is why you see all of these funny emit_branch() and |
| 354 | * emit_jump() calls with adjusted offsets. |
| 355 | */ |
| 356 | |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 357 | void bpf_jit_compile(struct sk_filter *fp) |
| 358 | { |
| 359 | unsigned int cleanup_addr, proglen, oldproglen = 0; |
| 360 | u32 temp[8], *prog, *func, seen = 0, pass; |
| 361 | const struct sock_filter *filter = fp->insns; |
| 362 | int i, flen = fp->len, pc_ret0 = -1; |
| 363 | unsigned int *addrs; |
| 364 | void *image; |
| 365 | |
| 366 | if (!bpf_jit_enable) |
| 367 | return; |
| 368 | |
| 369 | addrs = kmalloc(flen * sizeof(*addrs), GFP_KERNEL); |
| 370 | if (addrs == NULL) |
| 371 | return; |
| 372 | |
| 373 | /* Before first pass, make a rough estimation of addrs[] |
| 374 | * each bpf instruction is translated to less than 64 bytes |
| 375 | */ |
| 376 | for (proglen = 0, i = 0; i < flen; i++) { |
| 377 | proglen += 64; |
| 378 | addrs[i] = proglen; |
| 379 | } |
| 380 | cleanup_addr = proglen; /* epilogue address */ |
| 381 | image = NULL; |
| 382 | for (pass = 0; pass < 10; pass++) { |
| 383 | u8 seen_or_pass0 = (pass == 0) ? (SEEN_XREG | SEEN_DATAREF | SEEN_MEM) : seen; |
| 384 | |
| 385 | /* no prologue/epilogue for trivial filters (RET something) */ |
| 386 | proglen = 0; |
| 387 | prog = temp; |
| 388 | |
| 389 | /* Prologue */ |
| 390 | if (seen_or_pass0) { |
| 391 | if (seen_or_pass0 & SEEN_MEM) { |
| 392 | unsigned int sz = BASE_STACKFRAME; |
| 393 | sz += BPF_MEMWORDS * sizeof(u32); |
| 394 | emit_alloc_stack(sz); |
| 395 | } |
| 396 | |
| 397 | /* Make sure we dont leek kernel memory. */ |
| 398 | if (seen_or_pass0 & SEEN_XREG) |
| 399 | emit_clear(r_X); |
| 400 | |
| 401 | /* If this filter needs to access skb data, |
David S. Miller | 7b56f76 | 2012-04-17 16:08:29 -0400 | [diff] [blame] | 402 | * load %o4 and %o5 with: |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 403 | * %o4 = skb->len - skb->data_len |
| 404 | * %o5 = skb->data |
| 405 | * And also back up %o7 into r_saved_O7 so we can |
| 406 | * invoke the stubs using 'call'. |
| 407 | */ |
| 408 | if (seen_or_pass0 & SEEN_DATAREF) { |
| 409 | emit_load32(r_SKB, struct sk_buff, len, r_HEADLEN); |
| 410 | emit_load32(r_SKB, struct sk_buff, data_len, r_TMP); |
| 411 | emit_sub(r_HEADLEN, r_TMP, r_HEADLEN); |
| 412 | emit_loadptr(r_SKB, struct sk_buff, data, r_SKB_DATA); |
| 413 | } |
| 414 | } |
| 415 | emit_reg_move(O7, r_saved_O7); |
| 416 | |
| 417 | switch (filter[0].code) { |
| 418 | case BPF_S_RET_K: |
| 419 | case BPF_S_LD_W_LEN: |
| 420 | case BPF_S_ANC_PROTOCOL: |
| 421 | case BPF_S_ANC_PKTTYPE: |
| 422 | case BPF_S_ANC_IFINDEX: |
| 423 | case BPF_S_ANC_MARK: |
| 424 | case BPF_S_ANC_RXHASH: |
Daniel Borkmann | 54e7e2d | 2012-11-04 16:59:30 +0000 | [diff] [blame] | 425 | case BPF_S_ANC_VLAN_TAG: |
| 426 | case BPF_S_ANC_VLAN_TAG_PRESENT: |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 427 | case BPF_S_ANC_CPU: |
| 428 | case BPF_S_ANC_QUEUE: |
| 429 | case BPF_S_LD_W_ABS: |
| 430 | case BPF_S_LD_H_ABS: |
| 431 | case BPF_S_LD_B_ABS: |
| 432 | /* The first instruction sets the A register (or is |
| 433 | * a "RET 'constant'") |
| 434 | */ |
| 435 | break; |
| 436 | default: |
| 437 | /* Make sure we dont leak kernel information to the |
| 438 | * user. |
| 439 | */ |
| 440 | emit_clear(r_A); /* A = 0 */ |
| 441 | } |
| 442 | |
| 443 | for (i = 0; i < flen; i++) { |
| 444 | unsigned int K = filter[i].k; |
| 445 | unsigned int t_offset; |
| 446 | unsigned int f_offset; |
| 447 | u32 t_op, f_op; |
| 448 | int ilen; |
| 449 | |
| 450 | switch (filter[i].code) { |
| 451 | case BPF_S_ALU_ADD_X: /* A += X; */ |
| 452 | emit_alu_X(ADD); |
| 453 | break; |
| 454 | case BPF_S_ALU_ADD_K: /* A += K; */ |
| 455 | emit_alu_K(ADD, K); |
| 456 | break; |
| 457 | case BPF_S_ALU_SUB_X: /* A -= X; */ |
| 458 | emit_alu_X(SUB); |
| 459 | break; |
| 460 | case BPF_S_ALU_SUB_K: /* A -= K */ |
| 461 | emit_alu_K(SUB, K); |
| 462 | break; |
| 463 | case BPF_S_ALU_AND_X: /* A &= X */ |
| 464 | emit_alu_X(AND); |
| 465 | break; |
| 466 | case BPF_S_ALU_AND_K: /* A &= K */ |
| 467 | emit_alu_K(AND, K); |
| 468 | break; |
| 469 | case BPF_S_ALU_OR_X: /* A |= X */ |
| 470 | emit_alu_X(OR); |
| 471 | break; |
| 472 | case BPF_S_ALU_OR_K: /* A |= K */ |
| 473 | emit_alu_K(OR, K); |
| 474 | break; |
David S. Miller | d7ce8a5 | 2012-06-06 10:20:21 -0700 | [diff] [blame] | 475 | case BPF_S_ANC_ALU_XOR_X: /* A ^= X; */ |
Daniel Borkmann | aa99521 | 2012-09-24 11:57:54 +0000 | [diff] [blame] | 476 | case BPF_S_ALU_XOR_X: |
David S. Miller | d7ce8a5 | 2012-06-06 10:20:21 -0700 | [diff] [blame] | 477 | emit_alu_X(XOR); |
| 478 | break; |
Daniel Borkmann | aa99521 | 2012-09-24 11:57:54 +0000 | [diff] [blame] | 479 | case BPF_S_ALU_XOR_K: /* A ^= K */ |
| 480 | emit_alu_K(XOR, K); |
| 481 | break; |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 482 | case BPF_S_ALU_LSH_X: /* A <<= X */ |
| 483 | emit_alu_X(SLL); |
| 484 | break; |
| 485 | case BPF_S_ALU_LSH_K: /* A <<= K */ |
| 486 | emit_alu_K(SLL, K); |
| 487 | break; |
| 488 | case BPF_S_ALU_RSH_X: /* A >>= X */ |
| 489 | emit_alu_X(SRL); |
| 490 | break; |
| 491 | case BPF_S_ALU_RSH_K: /* A >>= K */ |
| 492 | emit_alu_K(SRL, K); |
| 493 | break; |
| 494 | case BPF_S_ALU_MUL_X: /* A *= X; */ |
| 495 | emit_alu_X(MUL); |
| 496 | break; |
| 497 | case BPF_S_ALU_MUL_K: /* A *= K */ |
| 498 | emit_alu_K(MUL, K); |
| 499 | break; |
Eric Dumazet | aee636c | 2014-01-15 06:50:07 -0800 | [diff] [blame] | 500 | case BPF_S_ALU_DIV_K: /* A /= K with K != 0*/ |
| 501 | if (K == 1) |
| 502 | break; |
| 503 | emit_write_y(G0); |
| 504 | #ifdef CONFIG_SPARC32 |
| 505 | /* The Sparc v8 architecture requires |
| 506 | * three instructions between a %y |
| 507 | * register write and the first use. |
| 508 | */ |
| 509 | emit_nop(); |
| 510 | emit_nop(); |
| 511 | emit_nop(); |
| 512 | #endif |
| 513 | emit_alu_K(DIV, K); |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 514 | break; |
| 515 | case BPF_S_ALU_DIV_X: /* A /= X; */ |
| 516 | emit_cmpi(r_X, 0); |
| 517 | if (pc_ret0 > 0) { |
| 518 | t_offset = addrs[pc_ret0 - 1]; |
| 519 | #ifdef CONFIG_SPARC32 |
| 520 | emit_branch(BE, t_offset + 20); |
| 521 | #else |
| 522 | emit_branch(BE, t_offset + 8); |
| 523 | #endif |
| 524 | emit_nop(); /* delay slot */ |
| 525 | } else { |
| 526 | emit_branch_off(BNE, 16); |
| 527 | emit_nop(); |
| 528 | #ifdef CONFIG_SPARC32 |
| 529 | emit_jump(cleanup_addr + 20); |
| 530 | #else |
| 531 | emit_jump(cleanup_addr + 8); |
| 532 | #endif |
| 533 | emit_clear(r_A); |
| 534 | } |
| 535 | emit_write_y(G0); |
| 536 | #ifdef CONFIG_SPARC32 |
David S. Miller | 584c5e2 | 2012-04-17 16:38:16 -0400 | [diff] [blame] | 537 | /* The Sparc v8 architecture requires |
| 538 | * three instructions between a %y |
| 539 | * register write and the first use. |
| 540 | */ |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 541 | emit_nop(); |
| 542 | emit_nop(); |
| 543 | emit_nop(); |
| 544 | #endif |
| 545 | emit_alu_X(DIV); |
| 546 | break; |
| 547 | case BPF_S_ALU_NEG: |
| 548 | emit_neg(); |
| 549 | break; |
| 550 | case BPF_S_RET_K: |
| 551 | if (!K) { |
| 552 | if (pc_ret0 == -1) |
| 553 | pc_ret0 = i; |
| 554 | emit_clear(r_A); |
| 555 | } else { |
| 556 | emit_loadimm(K, r_A); |
| 557 | } |
| 558 | /* Fallthrough */ |
| 559 | case BPF_S_RET_A: |
| 560 | if (seen_or_pass0) { |
| 561 | if (i != flen - 1) { |
| 562 | emit_jump(cleanup_addr); |
| 563 | emit_nop(); |
| 564 | break; |
| 565 | } |
| 566 | if (seen_or_pass0 & SEEN_MEM) { |
| 567 | unsigned int sz = BASE_STACKFRAME; |
| 568 | sz += BPF_MEMWORDS * sizeof(u32); |
| 569 | emit_release_stack(sz); |
| 570 | } |
| 571 | } |
| 572 | /* jmpl %r_saved_O7 + 8, %g0 */ |
| 573 | emit_jmpl(r_saved_O7, 8, G0); |
| 574 | emit_reg_move(r_A, O0); /* delay slot */ |
| 575 | break; |
| 576 | case BPF_S_MISC_TAX: |
| 577 | seen |= SEEN_XREG; |
| 578 | emit_reg_move(r_A, r_X); |
| 579 | break; |
| 580 | case BPF_S_MISC_TXA: |
| 581 | seen |= SEEN_XREG; |
| 582 | emit_reg_move(r_X, r_A); |
| 583 | break; |
| 584 | case BPF_S_ANC_CPU: |
| 585 | emit_load_cpu(r_A); |
| 586 | break; |
| 587 | case BPF_S_ANC_PROTOCOL: |
| 588 | emit_skb_load16(protocol, r_A); |
| 589 | break; |
| 590 | #if 0 |
| 591 | /* GCC won't let us take the address of |
| 592 | * a bit field even though we very much |
| 593 | * know what we are doing here. |
| 594 | */ |
| 595 | case BPF_S_ANC_PKTTYPE: |
| 596 | __emit_skb_load8(pkt_type, r_A); |
| 597 | emit_alu_K(SRL, 5); |
| 598 | break; |
| 599 | #endif |
| 600 | case BPF_S_ANC_IFINDEX: |
| 601 | emit_skb_loadptr(dev, r_A); |
| 602 | emit_cmpi(r_A, 0); |
| 603 | emit_branch(BNE_PTR, cleanup_addr + 4); |
| 604 | emit_nop(); |
| 605 | emit_load32(r_A, struct net_device, ifindex, r_A); |
| 606 | break; |
| 607 | case BPF_S_ANC_MARK: |
| 608 | emit_skb_load32(mark, r_A); |
| 609 | break; |
| 610 | case BPF_S_ANC_QUEUE: |
| 611 | emit_skb_load16(queue_mapping, r_A); |
| 612 | break; |
| 613 | case BPF_S_ANC_HATYPE: |
| 614 | emit_skb_loadptr(dev, r_A); |
| 615 | emit_cmpi(r_A, 0); |
| 616 | emit_branch(BNE_PTR, cleanup_addr + 4); |
| 617 | emit_nop(); |
| 618 | emit_load16(r_A, struct net_device, type, r_A); |
| 619 | break; |
| 620 | case BPF_S_ANC_RXHASH: |
| 621 | emit_skb_load32(rxhash, r_A); |
| 622 | break; |
Daniel Borkmann | 54e7e2d | 2012-11-04 16:59:30 +0000 | [diff] [blame] | 623 | case BPF_S_ANC_VLAN_TAG: |
| 624 | case BPF_S_ANC_VLAN_TAG_PRESENT: |
| 625 | emit_skb_load16(vlan_tci, r_A); |
| 626 | if (filter[i].code == BPF_S_ANC_VLAN_TAG) { |
| 627 | emit_andi(r_A, VLAN_VID_MASK, r_A); |
| 628 | } else { |
| 629 | emit_loadimm(VLAN_TAG_PRESENT, r_TMP); |
| 630 | emit_and(r_A, r_TMP, r_A); |
| 631 | } |
| 632 | break; |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 633 | |
| 634 | case BPF_S_LD_IMM: |
| 635 | emit_loadimm(K, r_A); |
| 636 | break; |
| 637 | case BPF_S_LDX_IMM: |
| 638 | emit_loadimm(K, r_X); |
| 639 | break; |
| 640 | case BPF_S_LD_MEM: |
| 641 | emit_ldmem(K * 4, r_A); |
| 642 | break; |
| 643 | case BPF_S_LDX_MEM: |
| 644 | emit_ldmem(K * 4, r_X); |
| 645 | break; |
| 646 | case BPF_S_ST: |
| 647 | emit_stmem(K * 4, r_A); |
| 648 | break; |
| 649 | case BPF_S_STX: |
| 650 | emit_stmem(K * 4, r_X); |
| 651 | break; |
| 652 | |
| 653 | #define CHOOSE_LOAD_FUNC(K, func) \ |
| 654 | ((int)K < 0 ? ((int)K >= SKF_LL_OFF ? func##_negative_offset : func) : func##_positive_offset) |
| 655 | |
| 656 | case BPF_S_LD_W_ABS: |
| 657 | func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_word); |
| 658 | common_load: seen |= SEEN_DATAREF; |
| 659 | emit_loadimm(K, r_OFF); |
| 660 | emit_call(func); |
| 661 | break; |
| 662 | case BPF_S_LD_H_ABS: |
| 663 | func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_half); |
| 664 | goto common_load; |
| 665 | case BPF_S_LD_B_ABS: |
| 666 | func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_byte); |
| 667 | goto common_load; |
| 668 | case BPF_S_LDX_B_MSH: |
| 669 | func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_byte_msh); |
| 670 | goto common_load; |
| 671 | case BPF_S_LD_W_IND: |
| 672 | func = bpf_jit_load_word; |
| 673 | common_load_ind: seen |= SEEN_DATAREF | SEEN_XREG; |
| 674 | if (K) { |
| 675 | if (is_simm13(K)) { |
| 676 | emit_addi(r_X, K, r_OFF); |
| 677 | } else { |
| 678 | emit_loadimm(K, r_TMP); |
| 679 | emit_add(r_X, r_TMP, r_OFF); |
| 680 | } |
| 681 | } else { |
| 682 | emit_reg_move(r_X, r_OFF); |
| 683 | } |
| 684 | emit_call(func); |
| 685 | break; |
| 686 | case BPF_S_LD_H_IND: |
| 687 | func = bpf_jit_load_half; |
| 688 | goto common_load_ind; |
| 689 | case BPF_S_LD_B_IND: |
| 690 | func = bpf_jit_load_byte; |
| 691 | goto common_load_ind; |
| 692 | case BPF_S_JMP_JA: |
| 693 | emit_jump(addrs[i + K]); |
| 694 | emit_nop(); |
| 695 | break; |
| 696 | |
| 697 | #define COND_SEL(CODE, TOP, FOP) \ |
| 698 | case CODE: \ |
| 699 | t_op = TOP; \ |
| 700 | f_op = FOP; \ |
| 701 | goto cond_branch |
| 702 | |
| 703 | COND_SEL(BPF_S_JMP_JGT_K, BGU, BLEU); |
| 704 | COND_SEL(BPF_S_JMP_JGE_K, BGEU, BLU); |
| 705 | COND_SEL(BPF_S_JMP_JEQ_K, BE, BNE); |
| 706 | COND_SEL(BPF_S_JMP_JSET_K, BNE, BE); |
| 707 | COND_SEL(BPF_S_JMP_JGT_X, BGU, BLEU); |
| 708 | COND_SEL(BPF_S_JMP_JGE_X, BGEU, BLU); |
| 709 | COND_SEL(BPF_S_JMP_JEQ_X, BE, BNE); |
| 710 | COND_SEL(BPF_S_JMP_JSET_X, BNE, BE); |
| 711 | |
| 712 | cond_branch: f_offset = addrs[i + filter[i].jf]; |
| 713 | t_offset = addrs[i + filter[i].jt]; |
| 714 | |
| 715 | /* same targets, can avoid doing the test :) */ |
| 716 | if (filter[i].jt == filter[i].jf) { |
| 717 | emit_jump(t_offset); |
| 718 | emit_nop(); |
| 719 | break; |
| 720 | } |
| 721 | |
| 722 | switch (filter[i].code) { |
| 723 | case BPF_S_JMP_JGT_X: |
| 724 | case BPF_S_JMP_JGE_X: |
| 725 | case BPF_S_JMP_JEQ_X: |
| 726 | seen |= SEEN_XREG; |
| 727 | emit_cmp(r_A, r_X); |
| 728 | break; |
| 729 | case BPF_S_JMP_JSET_X: |
| 730 | seen |= SEEN_XREG; |
| 731 | emit_btst(r_A, r_X); |
| 732 | break; |
| 733 | case BPF_S_JMP_JEQ_K: |
| 734 | case BPF_S_JMP_JGT_K: |
| 735 | case BPF_S_JMP_JGE_K: |
| 736 | if (is_simm13(K)) { |
| 737 | emit_cmpi(r_A, K); |
| 738 | } else { |
| 739 | emit_loadimm(K, r_TMP); |
| 740 | emit_cmp(r_A, r_TMP); |
| 741 | } |
| 742 | break; |
| 743 | case BPF_S_JMP_JSET_K: |
| 744 | if (is_simm13(K)) { |
| 745 | emit_btsti(r_A, K); |
| 746 | } else { |
| 747 | emit_loadimm(K, r_TMP); |
| 748 | emit_btst(r_A, r_TMP); |
| 749 | } |
| 750 | break; |
| 751 | } |
| 752 | if (filter[i].jt != 0) { |
| 753 | if (filter[i].jf) |
| 754 | t_offset += 8; |
| 755 | emit_branch(t_op, t_offset); |
| 756 | emit_nop(); /* delay slot */ |
| 757 | if (filter[i].jf) { |
| 758 | emit_jump(f_offset); |
| 759 | emit_nop(); |
| 760 | } |
| 761 | break; |
| 762 | } |
| 763 | emit_branch(f_op, f_offset); |
| 764 | emit_nop(); /* delay slot */ |
| 765 | break; |
| 766 | |
| 767 | default: |
| 768 | /* hmm, too complex filter, give up with jit compiler */ |
| 769 | goto out; |
| 770 | } |
| 771 | ilen = (void *) prog - (void *) temp; |
| 772 | if (image) { |
| 773 | if (unlikely(proglen + ilen > oldproglen)) { |
| 774 | pr_err("bpb_jit_compile fatal error\n"); |
| 775 | kfree(addrs); |
| 776 | module_free(NULL, image); |
| 777 | return; |
| 778 | } |
| 779 | memcpy(image + proglen, temp, ilen); |
| 780 | } |
| 781 | proglen += ilen; |
| 782 | addrs[i] = proglen; |
| 783 | prog = temp; |
| 784 | } |
| 785 | /* last bpf instruction is always a RET : |
| 786 | * use it to give the cleanup instruction(s) addr |
| 787 | */ |
| 788 | cleanup_addr = proglen - 8; /* jmpl; mov r_A,%o0; */ |
| 789 | if (seen_or_pass0 & SEEN_MEM) |
| 790 | cleanup_addr -= 4; /* add %sp, X, %sp; */ |
| 791 | |
| 792 | if (image) { |
| 793 | if (proglen != oldproglen) |
| 794 | pr_err("bpb_jit_compile proglen=%u != oldproglen=%u\n", |
| 795 | proglen, oldproglen); |
| 796 | break; |
| 797 | } |
| 798 | if (proglen == oldproglen) { |
Eric Dumazet | 5199dfe | 2013-05-17 12:12:34 +0000 | [diff] [blame] | 799 | image = module_alloc(proglen); |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 800 | if (!image) |
| 801 | goto out; |
| 802 | } |
| 803 | oldproglen = proglen; |
| 804 | } |
| 805 | |
| 806 | if (bpf_jit_enable > 1) |
Daniel Borkmann | 7961780 | 2013-03-21 22:22:03 +0100 | [diff] [blame] | 807 | bpf_jit_dump(flen, proglen, pass, image); |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 808 | |
| 809 | if (image) { |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 810 | bpf_flush_icache(image, image + proglen); |
| 811 | fp->bpf_func = (void *)image; |
| 812 | } |
| 813 | out: |
| 814 | kfree(addrs); |
| 815 | return; |
| 816 | } |
| 817 | |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 818 | void bpf_jit_free(struct sk_filter *fp) |
| 819 | { |
Eric Dumazet | 5199dfe | 2013-05-17 12:12:34 +0000 | [diff] [blame] | 820 | if (fp->bpf_func != sk_run_filter) |
| 821 | module_free(NULL, fp->bpf_func); |
Alexei Starovoitov | d45ed4a | 2013-10-04 00:14:06 -0700 | [diff] [blame] | 822 | kfree(fp); |
David S. Miller | 2809a2087 | 2012-04-15 20:06:27 -0700 | [diff] [blame] | 823 | } |