Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1 | /* |
| 2 | * BPF Jit compiler for s390. |
| 3 | * |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 4 | * Minimum build requirements: |
| 5 | * |
| 6 | * - HAVE_MARCH_Z196_FEATURES: laal, laalg |
| 7 | * - HAVE_MARCH_Z10_FEATURES: msfi, cgrj, clgrj |
| 8 | * - HAVE_MARCH_Z9_109_FEATURES: alfi, llilf, clfi, oilf, nilf |
| 9 | * - PACK_STACK |
| 10 | * - 64BIT |
| 11 | * |
| 12 | * Copyright IBM Corp. 2012,2015 |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 13 | * |
| 14 | * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 15 | * Michael Holzheu <holzheu@linux.vnet.ibm.com> |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 16 | */ |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 17 | |
| 18 | #define KMSG_COMPONENT "bpf_jit" |
| 19 | #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt |
| 20 | |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 21 | #include <linux/netdevice.h> |
| 22 | #include <linux/filter.h> |
Heiko Carstens | c9a7afa | 2013-07-17 14:26:50 +0200 | [diff] [blame] | 23 | #include <linux/init.h> |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 24 | #include <asm/cacheflush.h> |
Heiko Carstens | 0f20822 | 2013-09-13 13:36:25 +0200 | [diff] [blame] | 25 | #include <asm/dis.h> |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 26 | #include "bpf_jit.h" |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 27 | |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 28 | int bpf_jit_enable __read_mostly; |
| 29 | |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 30 | struct bpf_jit { |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 31 | u32 seen; /* Flags to remember seen eBPF instructions */ |
| 32 | u32 seen_reg[16]; /* Array to remember which registers are used */ |
| 33 | u32 *addrs; /* Array with relative instruction addresses */ |
| 34 | u8 *prg_buf; /* Start of program */ |
| 35 | int size; /* Size of program and literal pool */ |
| 36 | int size_prg; /* Size of program */ |
| 37 | int prg; /* Current position in program */ |
| 38 | int lit_start; /* Start of literal pool */ |
| 39 | int lit; /* Current position in literal pool */ |
| 40 | int base_ip; /* Base address for literal pool */ |
| 41 | int ret0_ip; /* Address of return 0 */ |
| 42 | int exit_ip; /* Address of exit */ |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 43 | }; |
| 44 | |
| 45 | #define BPF_SIZE_MAX 4096 /* Max size for program */ |
| 46 | |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 47 | #define SEEN_SKB 1 /* skb access */ |
| 48 | #define SEEN_MEM 2 /* use mem[] for temporary storage */ |
| 49 | #define SEEN_RET0 4 /* ret0_ip points to a valid return 0 */ |
| 50 | #define SEEN_LITERAL 8 /* code uses literals */ |
| 51 | #define SEEN_FUNC 16 /* calls C functions */ |
| 52 | #define SEEN_STACK (SEEN_FUNC | SEEN_MEM | SEEN_SKB) |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 53 | |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 54 | /* |
| 55 | * s390 registers |
| 56 | */ |
| 57 | #define REG_W0 (__MAX_BPF_REG+0) /* Work register 1 (even) */ |
| 58 | #define REG_W1 (__MAX_BPF_REG+1) /* Work register 2 (odd) */ |
| 59 | #define REG_SKB_DATA (__MAX_BPF_REG+2) /* SKB data register */ |
| 60 | #define REG_L (__MAX_BPF_REG+3) /* Literal pool register */ |
| 61 | #define REG_15 (__MAX_BPF_REG+4) /* Register 15 */ |
| 62 | #define REG_0 REG_W0 /* Register 0 */ |
| 63 | #define REG_2 BPF_REG_1 /* Register 2 */ |
| 64 | #define REG_14 BPF_REG_0 /* Register 14 */ |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 65 | |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 66 | /* |
| 67 | * Mapping of BPF registers to s390 registers |
| 68 | */ |
| 69 | static const int reg2hex[] = { |
| 70 | /* Return code */ |
| 71 | [BPF_REG_0] = 14, |
| 72 | /* Function parameters */ |
| 73 | [BPF_REG_1] = 2, |
| 74 | [BPF_REG_2] = 3, |
| 75 | [BPF_REG_3] = 4, |
| 76 | [BPF_REG_4] = 5, |
| 77 | [BPF_REG_5] = 6, |
| 78 | /* Call saved registers */ |
| 79 | [BPF_REG_6] = 7, |
| 80 | [BPF_REG_7] = 8, |
| 81 | [BPF_REG_8] = 9, |
| 82 | [BPF_REG_9] = 10, |
| 83 | /* BPF stack pointer */ |
| 84 | [BPF_REG_FP] = 13, |
| 85 | /* SKB data pointer */ |
| 86 | [REG_SKB_DATA] = 12, |
| 87 | /* Work registers for s390x backend */ |
| 88 | [REG_W0] = 0, |
| 89 | [REG_W1] = 1, |
| 90 | [REG_L] = 11, |
| 91 | [REG_15] = 15, |
| 92 | }; |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 93 | |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 94 | static inline u32 reg(u32 dst_reg, u32 src_reg) |
Daniel Borkmann | 738cbe7 | 2014-09-08 08:04:47 +0200 | [diff] [blame] | 95 | { |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 96 | return reg2hex[dst_reg] << 4 | reg2hex[src_reg]; |
| 97 | } |
| 98 | |
| 99 | static inline u32 reg_high(u32 reg) |
| 100 | { |
| 101 | return reg2hex[reg] << 4; |
| 102 | } |
| 103 | |
| 104 | static inline void reg_set_seen(struct bpf_jit *jit, u32 b1) |
| 105 | { |
| 106 | u32 r1 = reg2hex[b1]; |
| 107 | |
| 108 | if (!jit->seen_reg[r1] && r1 >= 6 && r1 <= 15) |
| 109 | jit->seen_reg[r1] = 1; |
| 110 | } |
| 111 | |
| 112 | #define REG_SET_SEEN(b1) \ |
| 113 | ({ \ |
| 114 | reg_set_seen(jit, b1); \ |
| 115 | }) |
| 116 | |
| 117 | #define REG_SEEN(b1) jit->seen_reg[reg2hex[(b1)]] |
| 118 | |
| 119 | /* |
| 120 | * EMIT macros for code generation |
| 121 | */ |
| 122 | |
| 123 | #define _EMIT2(op) \ |
| 124 | ({ \ |
| 125 | if (jit->prg_buf) \ |
| 126 | *(u16 *) (jit->prg_buf + jit->prg) = op; \ |
| 127 | jit->prg += 2; \ |
| 128 | }) |
| 129 | |
| 130 | #define EMIT2(op, b1, b2) \ |
| 131 | ({ \ |
| 132 | _EMIT2(op | reg(b1, b2)); \ |
| 133 | REG_SET_SEEN(b1); \ |
| 134 | REG_SET_SEEN(b2); \ |
| 135 | }) |
| 136 | |
| 137 | #define _EMIT4(op) \ |
| 138 | ({ \ |
| 139 | if (jit->prg_buf) \ |
| 140 | *(u32 *) (jit->prg_buf + jit->prg) = op; \ |
| 141 | jit->prg += 4; \ |
| 142 | }) |
| 143 | |
| 144 | #define EMIT4(op, b1, b2) \ |
| 145 | ({ \ |
| 146 | _EMIT4(op | reg(b1, b2)); \ |
| 147 | REG_SET_SEEN(b1); \ |
| 148 | REG_SET_SEEN(b2); \ |
| 149 | }) |
| 150 | |
| 151 | #define EMIT4_RRF(op, b1, b2, b3) \ |
| 152 | ({ \ |
| 153 | _EMIT4(op | reg_high(b3) << 8 | reg(b1, b2)); \ |
| 154 | REG_SET_SEEN(b1); \ |
| 155 | REG_SET_SEEN(b2); \ |
| 156 | REG_SET_SEEN(b3); \ |
| 157 | }) |
| 158 | |
| 159 | #define _EMIT4_DISP(op, disp) \ |
| 160 | ({ \ |
| 161 | unsigned int __disp = (disp) & 0xfff; \ |
| 162 | _EMIT4(op | __disp); \ |
| 163 | }) |
| 164 | |
| 165 | #define EMIT4_DISP(op, b1, b2, disp) \ |
| 166 | ({ \ |
| 167 | _EMIT4_DISP(op | reg_high(b1) << 16 | \ |
| 168 | reg_high(b2) << 8, disp); \ |
| 169 | REG_SET_SEEN(b1); \ |
| 170 | REG_SET_SEEN(b2); \ |
| 171 | }) |
| 172 | |
| 173 | #define EMIT4_IMM(op, b1, imm) \ |
| 174 | ({ \ |
| 175 | unsigned int __imm = (imm) & 0xffff; \ |
| 176 | _EMIT4(op | reg_high(b1) << 16 | __imm); \ |
| 177 | REG_SET_SEEN(b1); \ |
| 178 | }) |
| 179 | |
| 180 | #define EMIT4_PCREL(op, pcrel) \ |
| 181 | ({ \ |
| 182 | long __pcrel = ((pcrel) >> 1) & 0xffff; \ |
| 183 | _EMIT4(op | __pcrel); \ |
| 184 | }) |
| 185 | |
| 186 | #define _EMIT6(op1, op2) \ |
| 187 | ({ \ |
| 188 | if (jit->prg_buf) { \ |
| 189 | *(u32 *) (jit->prg_buf + jit->prg) = op1; \ |
| 190 | *(u16 *) (jit->prg_buf + jit->prg + 4) = op2; \ |
| 191 | } \ |
| 192 | jit->prg += 6; \ |
| 193 | }) |
| 194 | |
| 195 | #define _EMIT6_DISP(op1, op2, disp) \ |
| 196 | ({ \ |
| 197 | unsigned int __disp = (disp) & 0xfff; \ |
| 198 | _EMIT6(op1 | __disp, op2); \ |
| 199 | }) |
| 200 | |
| 201 | #define EMIT6_DISP(op1, op2, b1, b2, b3, disp) \ |
| 202 | ({ \ |
| 203 | _EMIT6_DISP(op1 | reg(b1, b2) << 16 | \ |
| 204 | reg_high(b3) << 8, op2, disp); \ |
| 205 | REG_SET_SEEN(b1); \ |
| 206 | REG_SET_SEEN(b2); \ |
| 207 | REG_SET_SEEN(b3); \ |
| 208 | }) |
| 209 | |
| 210 | #define _EMIT6_DISP_LH(op1, op2, disp) \ |
| 211 | ({ \ |
| 212 | unsigned int __disp_h = ((u32)disp) & 0xff000; \ |
| 213 | unsigned int __disp_l = ((u32)disp) & 0x00fff; \ |
| 214 | _EMIT6(op1 | __disp_l, op2 | __disp_h >> 4); \ |
| 215 | }) |
| 216 | |
| 217 | #define EMIT6_DISP_LH(op1, op2, b1, b2, b3, disp) \ |
| 218 | ({ \ |
| 219 | _EMIT6_DISP_LH(op1 | reg(b1, b2) << 16 | \ |
| 220 | reg_high(b3) << 8, op2, disp); \ |
| 221 | REG_SET_SEEN(b1); \ |
| 222 | REG_SET_SEEN(b2); \ |
| 223 | REG_SET_SEEN(b3); \ |
| 224 | }) |
| 225 | |
| 226 | #define EMIT6_PCREL(op1, op2, b1, b2, i, off, mask) \ |
| 227 | ({ \ |
| 228 | /* Branch instruction needs 6 bytes */ \ |
| 229 | int rel = (addrs[i + off + 1] - (addrs[i + 1] - 6)) / 2;\ |
| 230 | _EMIT6(op1 | reg(b1, b2) << 16 | rel, op2 | mask); \ |
| 231 | REG_SET_SEEN(b1); \ |
| 232 | REG_SET_SEEN(b2); \ |
| 233 | }) |
| 234 | |
| 235 | #define _EMIT6_IMM(op, imm) \ |
| 236 | ({ \ |
| 237 | unsigned int __imm = (imm); \ |
| 238 | _EMIT6(op | (__imm >> 16), __imm & 0xffff); \ |
| 239 | }) |
| 240 | |
| 241 | #define EMIT6_IMM(op, b1, imm) \ |
| 242 | ({ \ |
| 243 | _EMIT6_IMM(op | reg_high(b1) << 16, imm); \ |
| 244 | REG_SET_SEEN(b1); \ |
| 245 | }) |
| 246 | |
| 247 | #define EMIT_CONST_U32(val) \ |
| 248 | ({ \ |
| 249 | unsigned int ret; \ |
| 250 | ret = jit->lit - jit->base_ip; \ |
| 251 | jit->seen |= SEEN_LITERAL; \ |
| 252 | if (jit->prg_buf) \ |
| 253 | *(u32 *) (jit->prg_buf + jit->lit) = (u32) val; \ |
| 254 | jit->lit += 4; \ |
| 255 | ret; \ |
| 256 | }) |
| 257 | |
| 258 | #define EMIT_CONST_U64(val) \ |
| 259 | ({ \ |
| 260 | unsigned int ret; \ |
| 261 | ret = jit->lit - jit->base_ip; \ |
| 262 | jit->seen |= SEEN_LITERAL; \ |
| 263 | if (jit->prg_buf) \ |
| 264 | *(u64 *) (jit->prg_buf + jit->lit) = (u64) val; \ |
| 265 | jit->lit += 8; \ |
| 266 | ret; \ |
| 267 | }) |
| 268 | |
| 269 | #define EMIT_ZERO(b1) \ |
| 270 | ({ \ |
| 271 | /* llgfr %dst,%dst (zero extend to 64 bit) */ \ |
| 272 | EMIT4(0xb9160000, b1, b1); \ |
| 273 | REG_SET_SEEN(b1); \ |
| 274 | }) |
| 275 | |
| 276 | /* |
| 277 | * Fill whole space with illegal instructions |
| 278 | */ |
| 279 | static void jit_fill_hole(void *area, unsigned int size) |
| 280 | { |
Daniel Borkmann | 738cbe7 | 2014-09-08 08:04:47 +0200 | [diff] [blame] | 281 | memset(area, 0, size); |
| 282 | } |
| 283 | |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 284 | /* |
| 285 | * Save registers from "rs" (register start) to "re" (register end) on stack |
| 286 | */ |
| 287 | static void save_regs(struct bpf_jit *jit, u32 rs, u32 re) |
| 288 | { |
| 289 | u32 off = 72 + (rs - 6) * 8; |
| 290 | |
| 291 | if (rs == re) |
| 292 | /* stg %rs,off(%r15) */ |
| 293 | _EMIT6(0xe300f000 | rs << 20 | off, 0x0024); |
| 294 | else |
| 295 | /* stmg %rs,%re,off(%r15) */ |
| 296 | _EMIT6_DISP(0xeb00f000 | rs << 20 | re << 16, 0x0024, off); |
| 297 | } |
| 298 | |
| 299 | /* |
| 300 | * Restore registers from "rs" (register start) to "re" (register end) on stack |
| 301 | */ |
| 302 | static void restore_regs(struct bpf_jit *jit, u32 rs, u32 re) |
| 303 | { |
| 304 | u32 off = 72 + (rs - 6) * 8; |
| 305 | |
| 306 | if (jit->seen & SEEN_STACK) |
| 307 | off += STK_OFF; |
| 308 | |
| 309 | if (rs == re) |
| 310 | /* lg %rs,off(%r15) */ |
| 311 | _EMIT6(0xe300f000 | rs << 20 | off, 0x0004); |
| 312 | else |
| 313 | /* lmg %rs,%re,off(%r15) */ |
| 314 | _EMIT6_DISP(0xeb00f000 | rs << 20 | re << 16, 0x0004, off); |
| 315 | } |
| 316 | |
| 317 | /* |
| 318 | * Return first seen register (from start) |
| 319 | */ |
| 320 | static int get_start(struct bpf_jit *jit, int start) |
| 321 | { |
| 322 | int i; |
| 323 | |
| 324 | for (i = start; i <= 15; i++) { |
| 325 | if (jit->seen_reg[i]) |
| 326 | return i; |
| 327 | } |
| 328 | return 0; |
| 329 | } |
| 330 | |
| 331 | /* |
| 332 | * Return last seen register (from start) (gap >= 2) |
| 333 | */ |
| 334 | static int get_end(struct bpf_jit *jit, int start) |
| 335 | { |
| 336 | int i; |
| 337 | |
| 338 | for (i = start; i < 15; i++) { |
| 339 | if (!jit->seen_reg[i] && !jit->seen_reg[i + 1]) |
| 340 | return i - 1; |
| 341 | } |
| 342 | return jit->seen_reg[15] ? 15 : 14; |
| 343 | } |
| 344 | |
| 345 | #define REGS_SAVE 1 |
| 346 | #define REGS_RESTORE 0 |
| 347 | /* |
| 348 | * Save and restore clobbered registers (6-15) on stack. |
| 349 | * We save/restore registers in chunks with gap >= 2 registers. |
| 350 | */ |
| 351 | static void save_restore_regs(struct bpf_jit *jit, int op) |
| 352 | { |
| 353 | |
| 354 | int re = 6, rs; |
| 355 | |
| 356 | do { |
| 357 | rs = get_start(jit, re); |
| 358 | if (!rs) |
| 359 | break; |
| 360 | re = get_end(jit, rs + 1); |
| 361 | if (op == REGS_SAVE) |
| 362 | save_regs(jit, rs, re); |
| 363 | else |
| 364 | restore_regs(jit, rs, re); |
| 365 | re++; |
| 366 | } while (re <= 15); |
| 367 | } |
| 368 | |
| 369 | /* |
| 370 | * Emit function prologue |
| 371 | * |
| 372 | * Save registers and create stack frame if necessary. |
| 373 | * See stack frame layout desription in "bpf_jit.h"! |
| 374 | */ |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 375 | static void bpf_jit_prologue(struct bpf_jit *jit) |
| 376 | { |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 377 | /* Save registers */ |
| 378 | save_restore_regs(jit, REGS_SAVE); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 379 | /* Setup literal pool */ |
| 380 | if (jit->seen & SEEN_LITERAL) { |
| 381 | /* basr %r13,0 */ |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 382 | EMIT2(0x0d00, REG_L, REG_0); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 383 | jit->base_ip = jit->prg; |
| 384 | } |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 385 | /* Setup stack and backchain */ |
| 386 | if (jit->seen & SEEN_STACK) { |
| 387 | /* lgr %bfp,%r15 (BPF frame pointer) */ |
| 388 | EMIT4(0xb9040000, BPF_REG_FP, REG_15); |
| 389 | /* aghi %r15,-STK_OFF */ |
| 390 | EMIT4_IMM(0xa70b0000, REG_15, -STK_OFF); |
| 391 | if (jit->seen & SEEN_FUNC) |
| 392 | /* stg %bfp,152(%r15) (backchain) */ |
| 393 | EMIT6_DISP_LH(0xe3000000, 0x0024, BPF_REG_FP, REG_0, |
| 394 | REG_15, 152); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 395 | } |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 396 | /* |
| 397 | * For SKB access %b1 contains the SKB pointer. For "bpf_jit.S" |
| 398 | * we store the SKB header length on the stack and the SKB data |
| 399 | * pointer in REG_SKB_DATA. |
| 400 | */ |
| 401 | if (jit->seen & SEEN_SKB) { |
| 402 | /* Header length: llgf %w1,<len>(%b1) */ |
| 403 | EMIT6_DISP_LH(0xe3000000, 0x0016, REG_W1, REG_0, BPF_REG_1, |
| 404 | offsetof(struct sk_buff, len)); |
| 405 | /* s %w1,<data_len>(%b1) */ |
| 406 | EMIT4_DISP(0x5b000000, REG_W1, BPF_REG_1, |
| 407 | offsetof(struct sk_buff, data_len)); |
| 408 | /* stg %w1,ST_OFF_HLEN(%r0,%r15) */ |
| 409 | EMIT6_DISP_LH(0xe3000000, 0x0024, REG_W1, REG_0, REG_15, |
| 410 | STK_OFF_HLEN); |
| 411 | /* lg %skb_data,data_off(%b1) */ |
| 412 | EMIT6_DISP_LH(0xe3000000, 0x0004, REG_SKB_DATA, REG_0, |
| 413 | BPF_REG_1, offsetof(struct sk_buff, data)); |
| 414 | } |
| 415 | /* BPF compatibility: clear A (%b7) and X (%b8) registers */ |
| 416 | if (REG_SEEN(BPF_REG_7)) |
| 417 | /* lghi %b7,0 */ |
| 418 | EMIT4_IMM(0xa7090000, BPF_REG_7, 0); |
| 419 | if (REG_SEEN(BPF_REG_8)) |
| 420 | /* lghi %b8,0 */ |
| 421 | EMIT4_IMM(0xa7090000, BPF_REG_8, 0); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 422 | } |
| 423 | |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 424 | /* |
| 425 | * Function epilogue |
| 426 | */ |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 427 | static void bpf_jit_epilogue(struct bpf_jit *jit) |
| 428 | { |
| 429 | /* Return 0 */ |
| 430 | if (jit->seen & SEEN_RET0) { |
| 431 | jit->ret0_ip = jit->prg; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 432 | /* lghi %b0,0 */ |
| 433 | EMIT4_IMM(0xa7090000, BPF_REG_0, 0); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 434 | } |
| 435 | jit->exit_ip = jit->prg; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 436 | /* Load exit code: lgr %r2,%b0 */ |
| 437 | EMIT4(0xb9040000, REG_2, BPF_REG_0); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 438 | /* Restore registers */ |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 439 | save_restore_regs(jit, REGS_RESTORE); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 440 | /* br %r14 */ |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 441 | _EMIT2(0x07fe); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 442 | } |
| 443 | |
| 444 | /* |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 445 | * Compile one eBPF instruction into s390x code |
Michael Holzheu | b9b4b1c | 2015-04-29 18:45:03 +0200 | [diff] [blame] | 446 | * |
| 447 | * NOTE: Use noinline because for gcov (-fprofile-arcs) gcc allocates a lot of |
| 448 | * stack space for the large switch statement. |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 449 | */ |
Michael Holzheu | b9b4b1c | 2015-04-29 18:45:03 +0200 | [diff] [blame] | 450 | static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp, int i) |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 451 | { |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 452 | struct bpf_insn *insn = &fp->insnsi[i]; |
| 453 | int jmp_off, last, insn_count = 1; |
| 454 | unsigned int func_addr, mask; |
| 455 | u32 dst_reg = insn->dst_reg; |
| 456 | u32 src_reg = insn->src_reg; |
| 457 | u32 *addrs = jit->addrs; |
| 458 | s32 imm = insn->imm; |
| 459 | s16 off = insn->off; |
| 460 | |
| 461 | switch (insn->code) { |
| 462 | /* |
| 463 | * BPF_MOV |
| 464 | */ |
| 465 | case BPF_ALU | BPF_MOV | BPF_X: /* dst = (u32) src */ |
| 466 | /* llgfr %dst,%src */ |
| 467 | EMIT4(0xb9160000, dst_reg, src_reg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 468 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 469 | case BPF_ALU64 | BPF_MOV | BPF_X: /* dst = src */ |
| 470 | /* lgr %dst,%src */ |
| 471 | EMIT4(0xb9040000, dst_reg, src_reg); |
| 472 | break; |
| 473 | case BPF_ALU | BPF_MOV | BPF_K: /* dst = (u32) imm */ |
| 474 | /* llilf %dst,imm */ |
| 475 | EMIT6_IMM(0xc00f0000, dst_reg, imm); |
| 476 | break; |
| 477 | case BPF_ALU64 | BPF_MOV | BPF_K: /* dst = imm */ |
| 478 | /* lgfi %dst,imm */ |
| 479 | EMIT6_IMM(0xc0010000, dst_reg, imm); |
| 480 | break; |
| 481 | /* |
| 482 | * BPF_LD 64 |
| 483 | */ |
| 484 | case BPF_LD | BPF_IMM | BPF_DW: /* dst = (u64) imm */ |
| 485 | { |
| 486 | /* 16 byte instruction that uses two 'struct bpf_insn' */ |
| 487 | u64 imm64; |
| 488 | |
| 489 | imm64 = (u64)(u32) insn[0].imm | ((u64)(u32) insn[1].imm) << 32; |
| 490 | /* lg %dst,<d(imm)>(%l) */ |
| 491 | EMIT6_DISP_LH(0xe3000000, 0x0004, dst_reg, REG_0, REG_L, |
| 492 | EMIT_CONST_U64(imm64)); |
| 493 | insn_count = 2; |
| 494 | break; |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 495 | } |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 496 | /* |
| 497 | * BPF_ADD |
| 498 | */ |
| 499 | case BPF_ALU | BPF_ADD | BPF_X: /* dst = (u32) dst + (u32) src */ |
| 500 | /* ar %dst,%src */ |
| 501 | EMIT2(0x1a00, dst_reg, src_reg); |
| 502 | EMIT_ZERO(dst_reg); |
| 503 | break; |
| 504 | case BPF_ALU64 | BPF_ADD | BPF_X: /* dst = dst + src */ |
| 505 | /* agr %dst,%src */ |
| 506 | EMIT4(0xb9080000, dst_reg, src_reg); |
| 507 | break; |
| 508 | case BPF_ALU | BPF_ADD | BPF_K: /* dst = (u32) dst + (u32) imm */ |
| 509 | if (!imm) |
| 510 | break; |
| 511 | /* alfi %dst,imm */ |
| 512 | EMIT6_IMM(0xc20b0000, dst_reg, imm); |
| 513 | EMIT_ZERO(dst_reg); |
| 514 | break; |
| 515 | case BPF_ALU64 | BPF_ADD | BPF_K: /* dst = dst + imm */ |
| 516 | if (!imm) |
| 517 | break; |
| 518 | /* agfi %dst,imm */ |
| 519 | EMIT6_IMM(0xc2080000, dst_reg, imm); |
| 520 | break; |
| 521 | /* |
| 522 | * BPF_SUB |
| 523 | */ |
| 524 | case BPF_ALU | BPF_SUB | BPF_X: /* dst = (u32) dst - (u32) src */ |
| 525 | /* sr %dst,%src */ |
| 526 | EMIT2(0x1b00, dst_reg, src_reg); |
| 527 | EMIT_ZERO(dst_reg); |
| 528 | break; |
| 529 | case BPF_ALU64 | BPF_SUB | BPF_X: /* dst = dst - src */ |
| 530 | /* sgr %dst,%src */ |
| 531 | EMIT4(0xb9090000, dst_reg, src_reg); |
| 532 | break; |
| 533 | case BPF_ALU | BPF_SUB | BPF_K: /* dst = (u32) dst - (u32) imm */ |
| 534 | if (!imm) |
| 535 | break; |
| 536 | /* alfi %dst,-imm */ |
| 537 | EMIT6_IMM(0xc20b0000, dst_reg, -imm); |
| 538 | EMIT_ZERO(dst_reg); |
| 539 | break; |
| 540 | case BPF_ALU64 | BPF_SUB | BPF_K: /* dst = dst - imm */ |
| 541 | if (!imm) |
| 542 | break; |
| 543 | /* agfi %dst,-imm */ |
| 544 | EMIT6_IMM(0xc2080000, dst_reg, -imm); |
| 545 | break; |
| 546 | /* |
| 547 | * BPF_MUL |
| 548 | */ |
| 549 | case BPF_ALU | BPF_MUL | BPF_X: /* dst = (u32) dst * (u32) src */ |
| 550 | /* msr %dst,%src */ |
| 551 | EMIT4(0xb2520000, dst_reg, src_reg); |
| 552 | EMIT_ZERO(dst_reg); |
| 553 | break; |
| 554 | case BPF_ALU64 | BPF_MUL | BPF_X: /* dst = dst * src */ |
| 555 | /* msgr %dst,%src */ |
| 556 | EMIT4(0xb90c0000, dst_reg, src_reg); |
| 557 | break; |
| 558 | case BPF_ALU | BPF_MUL | BPF_K: /* dst = (u32) dst * (u32) imm */ |
| 559 | if (imm == 1) |
| 560 | break; |
| 561 | /* msfi %r5,imm */ |
| 562 | EMIT6_IMM(0xc2010000, dst_reg, imm); |
| 563 | EMIT_ZERO(dst_reg); |
| 564 | break; |
| 565 | case BPF_ALU64 | BPF_MUL | BPF_K: /* dst = dst * imm */ |
| 566 | if (imm == 1) |
| 567 | break; |
| 568 | /* msgfi %dst,imm */ |
| 569 | EMIT6_IMM(0xc2000000, dst_reg, imm); |
| 570 | break; |
| 571 | /* |
| 572 | * BPF_DIV / BPF_MOD |
| 573 | */ |
| 574 | case BPF_ALU | BPF_DIV | BPF_X: /* dst = (u32) dst / (u32) src */ |
| 575 | case BPF_ALU | BPF_MOD | BPF_X: /* dst = (u32) dst % (u32) src */ |
| 576 | { |
| 577 | int rc_reg = BPF_OP(insn->code) == BPF_DIV ? REG_W1 : REG_W0; |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 578 | |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 579 | jit->seen |= SEEN_RET0; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 580 | /* ltr %src,%src (if src == 0 goto fail) */ |
| 581 | EMIT2(0x1200, src_reg, src_reg); |
| 582 | /* jz <ret0> */ |
| 583 | EMIT4_PCREL(0xa7840000, jit->ret0_ip - jit->prg); |
| 584 | /* lhi %w0,0 */ |
| 585 | EMIT4_IMM(0xa7080000, REG_W0, 0); |
| 586 | /* lr %w1,%dst */ |
| 587 | EMIT2(0x1800, REG_W1, dst_reg); |
| 588 | /* dlr %w0,%src */ |
| 589 | EMIT4(0xb9970000, REG_W0, src_reg); |
| 590 | /* llgfr %dst,%rc */ |
| 591 | EMIT4(0xb9160000, dst_reg, rc_reg); |
| 592 | break; |
| 593 | } |
Michael Holzheu | 771aada | 2015-04-27 11:12:25 +0200 | [diff] [blame] | 594 | case BPF_ALU64 | BPF_DIV | BPF_X: /* dst = dst / src */ |
| 595 | case BPF_ALU64 | BPF_MOD | BPF_X: /* dst = dst % src */ |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 596 | { |
| 597 | int rc_reg = BPF_OP(insn->code) == BPF_DIV ? REG_W1 : REG_W0; |
| 598 | |
| 599 | jit->seen |= SEEN_RET0; |
| 600 | /* ltgr %src,%src (if src == 0 goto fail) */ |
| 601 | EMIT4(0xb9020000, src_reg, src_reg); |
| 602 | /* jz <ret0> */ |
| 603 | EMIT4_PCREL(0xa7840000, jit->ret0_ip - jit->prg); |
| 604 | /* lghi %w0,0 */ |
| 605 | EMIT4_IMM(0xa7090000, REG_W0, 0); |
| 606 | /* lgr %w1,%dst */ |
| 607 | EMIT4(0xb9040000, REG_W1, dst_reg); |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 608 | /* dlgr %w0,%dst */ |
Michael Holzheu | 771aada | 2015-04-27 11:12:25 +0200 | [diff] [blame] | 609 | EMIT4(0xb9870000, REG_W0, src_reg); |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 610 | /* lgr %dst,%rc */ |
| 611 | EMIT4(0xb9040000, dst_reg, rc_reg); |
| 612 | break; |
| 613 | } |
| 614 | case BPF_ALU | BPF_DIV | BPF_K: /* dst = (u32) dst / (u32) imm */ |
| 615 | case BPF_ALU | BPF_MOD | BPF_K: /* dst = (u32) dst % (u32) imm */ |
| 616 | { |
| 617 | int rc_reg = BPF_OP(insn->code) == BPF_DIV ? REG_W1 : REG_W0; |
| 618 | |
| 619 | if (imm == 1) { |
| 620 | if (BPF_OP(insn->code) == BPF_MOD) |
| 621 | /* lhgi %dst,0 */ |
| 622 | EMIT4_IMM(0xa7090000, dst_reg, 0); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 623 | break; |
| 624 | } |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 625 | /* lhi %w0,0 */ |
| 626 | EMIT4_IMM(0xa7080000, REG_W0, 0); |
| 627 | /* lr %w1,%dst */ |
| 628 | EMIT2(0x1800, REG_W1, dst_reg); |
| 629 | /* dl %w0,<d(imm)>(%l) */ |
| 630 | EMIT6_DISP_LH(0xe3000000, 0x0097, REG_W0, REG_0, REG_L, |
| 631 | EMIT_CONST_U32(imm)); |
| 632 | /* llgfr %dst,%rc */ |
| 633 | EMIT4(0xb9160000, dst_reg, rc_reg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 634 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 635 | } |
Michael Holzheu | 771aada | 2015-04-27 11:12:25 +0200 | [diff] [blame] | 636 | case BPF_ALU64 | BPF_DIV | BPF_K: /* dst = dst / imm */ |
| 637 | case BPF_ALU64 | BPF_MOD | BPF_K: /* dst = dst % imm */ |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 638 | { |
| 639 | int rc_reg = BPF_OP(insn->code) == BPF_DIV ? REG_W1 : REG_W0; |
| 640 | |
| 641 | if (imm == 1) { |
| 642 | if (BPF_OP(insn->code) == BPF_MOD) |
| 643 | /* lhgi %dst,0 */ |
| 644 | EMIT4_IMM(0xa7090000, dst_reg, 0); |
| 645 | break; |
| 646 | } |
| 647 | /* lghi %w0,0 */ |
| 648 | EMIT4_IMM(0xa7090000, REG_W0, 0); |
| 649 | /* lgr %w1,%dst */ |
| 650 | EMIT4(0xb9040000, REG_W1, dst_reg); |
| 651 | /* dlg %w0,<d(imm)>(%l) */ |
| 652 | EMIT6_DISP_LH(0xe3000000, 0x0087, REG_W0, REG_0, REG_L, |
Michael Holzheu | 771aada | 2015-04-27 11:12:25 +0200 | [diff] [blame] | 653 | EMIT_CONST_U64(imm)); |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 654 | /* lgr %dst,%rc */ |
| 655 | EMIT4(0xb9040000, dst_reg, rc_reg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 656 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 657 | } |
| 658 | /* |
| 659 | * BPF_AND |
| 660 | */ |
| 661 | case BPF_ALU | BPF_AND | BPF_X: /* dst = (u32) dst & (u32) src */ |
| 662 | /* nr %dst,%src */ |
| 663 | EMIT2(0x1400, dst_reg, src_reg); |
| 664 | EMIT_ZERO(dst_reg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 665 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 666 | case BPF_ALU64 | BPF_AND | BPF_X: /* dst = dst & src */ |
| 667 | /* ngr %dst,%src */ |
| 668 | EMIT4(0xb9800000, dst_reg, src_reg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 669 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 670 | case BPF_ALU | BPF_AND | BPF_K: /* dst = (u32) dst & (u32) imm */ |
| 671 | /* nilf %dst,imm */ |
| 672 | EMIT6_IMM(0xc00b0000, dst_reg, imm); |
| 673 | EMIT_ZERO(dst_reg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 674 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 675 | case BPF_ALU64 | BPF_AND | BPF_K: /* dst = dst & imm */ |
| 676 | /* ng %dst,<d(imm)>(%l) */ |
| 677 | EMIT6_DISP_LH(0xe3000000, 0x0080, dst_reg, REG_0, REG_L, |
| 678 | EMIT_CONST_U64(imm)); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 679 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 680 | /* |
| 681 | * BPF_OR |
| 682 | */ |
| 683 | case BPF_ALU | BPF_OR | BPF_X: /* dst = (u32) dst | (u32) src */ |
| 684 | /* or %dst,%src */ |
| 685 | EMIT2(0x1600, dst_reg, src_reg); |
| 686 | EMIT_ZERO(dst_reg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 687 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 688 | case BPF_ALU64 | BPF_OR | BPF_X: /* dst = dst | src */ |
| 689 | /* ogr %dst,%src */ |
| 690 | EMIT4(0xb9810000, dst_reg, src_reg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 691 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 692 | case BPF_ALU | BPF_OR | BPF_K: /* dst = (u32) dst | (u32) imm */ |
| 693 | /* oilf %dst,imm */ |
| 694 | EMIT6_IMM(0xc00d0000, dst_reg, imm); |
| 695 | EMIT_ZERO(dst_reg); |
| 696 | break; |
| 697 | case BPF_ALU64 | BPF_OR | BPF_K: /* dst = dst | imm */ |
| 698 | /* og %dst,<d(imm)>(%l) */ |
| 699 | EMIT6_DISP_LH(0xe3000000, 0x0081, dst_reg, REG_0, REG_L, |
| 700 | EMIT_CONST_U64(imm)); |
| 701 | break; |
| 702 | /* |
| 703 | * BPF_XOR |
| 704 | */ |
| 705 | case BPF_ALU | BPF_XOR | BPF_X: /* dst = (u32) dst ^ (u32) src */ |
| 706 | /* xr %dst,%src */ |
| 707 | EMIT2(0x1700, dst_reg, src_reg); |
| 708 | EMIT_ZERO(dst_reg); |
| 709 | break; |
| 710 | case BPF_ALU64 | BPF_XOR | BPF_X: /* dst = dst ^ src */ |
| 711 | /* xgr %dst,%src */ |
| 712 | EMIT4(0xb9820000, dst_reg, src_reg); |
| 713 | break; |
| 714 | case BPF_ALU | BPF_XOR | BPF_K: /* dst = (u32) dst ^ (u32) imm */ |
| 715 | if (!imm) |
| 716 | break; |
| 717 | /* xilf %dst,imm */ |
| 718 | EMIT6_IMM(0xc0070000, dst_reg, imm); |
| 719 | EMIT_ZERO(dst_reg); |
| 720 | break; |
| 721 | case BPF_ALU64 | BPF_XOR | BPF_K: /* dst = dst ^ imm */ |
| 722 | /* xg %dst,<d(imm)>(%l) */ |
| 723 | EMIT6_DISP_LH(0xe3000000, 0x0082, dst_reg, REG_0, REG_L, |
| 724 | EMIT_CONST_U64(imm)); |
| 725 | break; |
| 726 | /* |
| 727 | * BPF_LSH |
| 728 | */ |
| 729 | case BPF_ALU | BPF_LSH | BPF_X: /* dst = (u32) dst << (u32) src */ |
| 730 | /* sll %dst,0(%src) */ |
| 731 | EMIT4_DISP(0x89000000, dst_reg, src_reg, 0); |
| 732 | EMIT_ZERO(dst_reg); |
| 733 | break; |
| 734 | case BPF_ALU64 | BPF_LSH | BPF_X: /* dst = dst << src */ |
| 735 | /* sllg %dst,%dst,0(%src) */ |
| 736 | EMIT6_DISP_LH(0xeb000000, 0x000d, dst_reg, dst_reg, src_reg, 0); |
| 737 | break; |
| 738 | case BPF_ALU | BPF_LSH | BPF_K: /* dst = (u32) dst << (u32) imm */ |
| 739 | if (imm == 0) |
| 740 | break; |
| 741 | /* sll %dst,imm(%r0) */ |
| 742 | EMIT4_DISP(0x89000000, dst_reg, REG_0, imm); |
| 743 | EMIT_ZERO(dst_reg); |
| 744 | break; |
| 745 | case BPF_ALU64 | BPF_LSH | BPF_K: /* dst = dst << imm */ |
| 746 | if (imm == 0) |
| 747 | break; |
| 748 | /* sllg %dst,%dst,imm(%r0) */ |
| 749 | EMIT6_DISP_LH(0xeb000000, 0x000d, dst_reg, dst_reg, REG_0, imm); |
| 750 | break; |
| 751 | /* |
| 752 | * BPF_RSH |
| 753 | */ |
| 754 | case BPF_ALU | BPF_RSH | BPF_X: /* dst = (u32) dst >> (u32) src */ |
| 755 | /* srl %dst,0(%src) */ |
| 756 | EMIT4_DISP(0x88000000, dst_reg, src_reg, 0); |
| 757 | EMIT_ZERO(dst_reg); |
| 758 | break; |
| 759 | case BPF_ALU64 | BPF_RSH | BPF_X: /* dst = dst >> src */ |
| 760 | /* srlg %dst,%dst,0(%src) */ |
| 761 | EMIT6_DISP_LH(0xeb000000, 0x000c, dst_reg, dst_reg, src_reg, 0); |
| 762 | break; |
| 763 | case BPF_ALU | BPF_RSH | BPF_K: /* dst = (u32) dst >> (u32) imm */ |
| 764 | if (imm == 0) |
| 765 | break; |
| 766 | /* srl %dst,imm(%r0) */ |
| 767 | EMIT4_DISP(0x88000000, dst_reg, REG_0, imm); |
| 768 | EMIT_ZERO(dst_reg); |
| 769 | break; |
| 770 | case BPF_ALU64 | BPF_RSH | BPF_K: /* dst = dst >> imm */ |
| 771 | if (imm == 0) |
| 772 | break; |
| 773 | /* srlg %dst,%dst,imm(%r0) */ |
| 774 | EMIT6_DISP_LH(0xeb000000, 0x000c, dst_reg, dst_reg, REG_0, imm); |
| 775 | break; |
| 776 | /* |
| 777 | * BPF_ARSH |
| 778 | */ |
| 779 | case BPF_ALU64 | BPF_ARSH | BPF_X: /* ((s64) dst) >>= src */ |
| 780 | /* srag %dst,%dst,0(%src) */ |
| 781 | EMIT6_DISP_LH(0xeb000000, 0x000a, dst_reg, dst_reg, src_reg, 0); |
| 782 | break; |
| 783 | case BPF_ALU64 | BPF_ARSH | BPF_K: /* ((s64) dst) >>= imm */ |
| 784 | if (imm == 0) |
| 785 | break; |
| 786 | /* srag %dst,%dst,imm(%r0) */ |
| 787 | EMIT6_DISP_LH(0xeb000000, 0x000a, dst_reg, dst_reg, REG_0, imm); |
| 788 | break; |
| 789 | /* |
| 790 | * BPF_NEG |
| 791 | */ |
| 792 | case BPF_ALU | BPF_NEG: /* dst = (u32) -dst */ |
| 793 | /* lcr %dst,%dst */ |
| 794 | EMIT2(0x1300, dst_reg, dst_reg); |
| 795 | EMIT_ZERO(dst_reg); |
| 796 | break; |
| 797 | case BPF_ALU64 | BPF_NEG: /* dst = -dst */ |
| 798 | /* lcgr %dst,%dst */ |
| 799 | EMIT4(0xb9130000, dst_reg, dst_reg); |
| 800 | break; |
| 801 | /* |
| 802 | * BPF_FROM_BE/LE |
| 803 | */ |
| 804 | case BPF_ALU | BPF_END | BPF_FROM_BE: |
| 805 | /* s390 is big endian, therefore only clear high order bytes */ |
| 806 | switch (imm) { |
| 807 | case 16: /* dst = (u16) cpu_to_be16(dst) */ |
| 808 | /* llghr %dst,%dst */ |
| 809 | EMIT4(0xb9850000, dst_reg, dst_reg); |
| 810 | break; |
| 811 | case 32: /* dst = (u32) cpu_to_be32(dst) */ |
| 812 | /* llgfr %dst,%dst */ |
| 813 | EMIT4(0xb9160000, dst_reg, dst_reg); |
| 814 | break; |
| 815 | case 64: /* dst = (u64) cpu_to_be64(dst) */ |
| 816 | break; |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 817 | } |
| 818 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 819 | case BPF_ALU | BPF_END | BPF_FROM_LE: |
| 820 | switch (imm) { |
| 821 | case 16: /* dst = (u16) cpu_to_le16(dst) */ |
| 822 | /* lrvr %dst,%dst */ |
| 823 | EMIT4(0xb91f0000, dst_reg, dst_reg); |
| 824 | /* srl %dst,16(%r0) */ |
| 825 | EMIT4_DISP(0x88000000, dst_reg, REG_0, 16); |
| 826 | /* llghr %dst,%dst */ |
| 827 | EMIT4(0xb9850000, dst_reg, dst_reg); |
| 828 | break; |
| 829 | case 32: /* dst = (u32) cpu_to_le32(dst) */ |
| 830 | /* lrvr %dst,%dst */ |
| 831 | EMIT4(0xb91f0000, dst_reg, dst_reg); |
| 832 | /* llgfr %dst,%dst */ |
| 833 | EMIT4(0xb9160000, dst_reg, dst_reg); |
| 834 | break; |
| 835 | case 64: /* dst = (u64) cpu_to_le64(dst) */ |
| 836 | /* lrvgr %dst,%dst */ |
| 837 | EMIT4(0xb90f0000, dst_reg, dst_reg); |
| 838 | break; |
| 839 | } |
| 840 | break; |
| 841 | /* |
| 842 | * BPF_ST(X) |
| 843 | */ |
| 844 | case BPF_STX | BPF_MEM | BPF_B: /* *(u8 *)(dst + off) = src_reg */ |
| 845 | /* stcy %src,off(%dst) */ |
| 846 | EMIT6_DISP_LH(0xe3000000, 0x0072, src_reg, dst_reg, REG_0, off); |
| 847 | jit->seen |= SEEN_MEM; |
| 848 | break; |
| 849 | case BPF_STX | BPF_MEM | BPF_H: /* (u16 *)(dst + off) = src */ |
| 850 | /* sthy %src,off(%dst) */ |
| 851 | EMIT6_DISP_LH(0xe3000000, 0x0070, src_reg, dst_reg, REG_0, off); |
| 852 | jit->seen |= SEEN_MEM; |
| 853 | break; |
| 854 | case BPF_STX | BPF_MEM | BPF_W: /* *(u32 *)(dst + off) = src */ |
| 855 | /* sty %src,off(%dst) */ |
| 856 | EMIT6_DISP_LH(0xe3000000, 0x0050, src_reg, dst_reg, REG_0, off); |
| 857 | jit->seen |= SEEN_MEM; |
| 858 | break; |
| 859 | case BPF_STX | BPF_MEM | BPF_DW: /* (u64 *)(dst + off) = src */ |
| 860 | /* stg %src,off(%dst) */ |
| 861 | EMIT6_DISP_LH(0xe3000000, 0x0024, src_reg, dst_reg, REG_0, off); |
| 862 | jit->seen |= SEEN_MEM; |
| 863 | break; |
| 864 | case BPF_ST | BPF_MEM | BPF_B: /* *(u8 *)(dst + off) = imm */ |
| 865 | /* lhi %w0,imm */ |
| 866 | EMIT4_IMM(0xa7080000, REG_W0, (u8) imm); |
| 867 | /* stcy %w0,off(dst) */ |
| 868 | EMIT6_DISP_LH(0xe3000000, 0x0072, REG_W0, dst_reg, REG_0, off); |
| 869 | jit->seen |= SEEN_MEM; |
| 870 | break; |
| 871 | case BPF_ST | BPF_MEM | BPF_H: /* (u16 *)(dst + off) = imm */ |
| 872 | /* lhi %w0,imm */ |
| 873 | EMIT4_IMM(0xa7080000, REG_W0, (u16) imm); |
| 874 | /* sthy %w0,off(dst) */ |
| 875 | EMIT6_DISP_LH(0xe3000000, 0x0070, REG_W0, dst_reg, REG_0, off); |
| 876 | jit->seen |= SEEN_MEM; |
| 877 | break; |
| 878 | case BPF_ST | BPF_MEM | BPF_W: /* *(u32 *)(dst + off) = imm */ |
| 879 | /* llilf %w0,imm */ |
| 880 | EMIT6_IMM(0xc00f0000, REG_W0, (u32) imm); |
| 881 | /* sty %w0,off(%dst) */ |
| 882 | EMIT6_DISP_LH(0xe3000000, 0x0050, REG_W0, dst_reg, REG_0, off); |
| 883 | jit->seen |= SEEN_MEM; |
| 884 | break; |
| 885 | case BPF_ST | BPF_MEM | BPF_DW: /* *(u64 *)(dst + off) = imm */ |
| 886 | /* lgfi %w0,imm */ |
| 887 | EMIT6_IMM(0xc0010000, REG_W0, imm); |
| 888 | /* stg %w0,off(%dst) */ |
| 889 | EMIT6_DISP_LH(0xe3000000, 0x0024, REG_W0, dst_reg, REG_0, off); |
| 890 | jit->seen |= SEEN_MEM; |
| 891 | break; |
| 892 | /* |
| 893 | * BPF_STX XADD (atomic_add) |
| 894 | */ |
| 895 | case BPF_STX | BPF_XADD | BPF_W: /* *(u32 *)(dst + off) += src */ |
| 896 | /* laal %w0,%src,off(%dst) */ |
| 897 | EMIT6_DISP_LH(0xeb000000, 0x00fa, REG_W0, src_reg, |
| 898 | dst_reg, off); |
| 899 | jit->seen |= SEEN_MEM; |
| 900 | break; |
| 901 | case BPF_STX | BPF_XADD | BPF_DW: /* *(u64 *)(dst + off) += src */ |
| 902 | /* laalg %w0,%src,off(%dst) */ |
| 903 | EMIT6_DISP_LH(0xeb000000, 0x00ea, REG_W0, src_reg, |
| 904 | dst_reg, off); |
| 905 | jit->seen |= SEEN_MEM; |
| 906 | break; |
| 907 | /* |
| 908 | * BPF_LDX |
| 909 | */ |
| 910 | case BPF_LDX | BPF_MEM | BPF_B: /* dst = *(u8 *)(ul) (src + off) */ |
| 911 | /* llgc %dst,0(off,%src) */ |
| 912 | EMIT6_DISP_LH(0xe3000000, 0x0090, dst_reg, src_reg, REG_0, off); |
| 913 | jit->seen |= SEEN_MEM; |
| 914 | break; |
| 915 | case BPF_LDX | BPF_MEM | BPF_H: /* dst = *(u16 *)(ul) (src + off) */ |
| 916 | /* llgh %dst,0(off,%src) */ |
| 917 | EMIT6_DISP_LH(0xe3000000, 0x0091, dst_reg, src_reg, REG_0, off); |
| 918 | jit->seen |= SEEN_MEM; |
| 919 | break; |
| 920 | case BPF_LDX | BPF_MEM | BPF_W: /* dst = *(u32 *)(ul) (src + off) */ |
| 921 | /* llgf %dst,off(%src) */ |
| 922 | jit->seen |= SEEN_MEM; |
| 923 | EMIT6_DISP_LH(0xe3000000, 0x0016, dst_reg, src_reg, REG_0, off); |
| 924 | break; |
| 925 | case BPF_LDX | BPF_MEM | BPF_DW: /* dst = *(u64 *)(ul) (src + off) */ |
| 926 | /* lg %dst,0(off,%src) */ |
| 927 | jit->seen |= SEEN_MEM; |
| 928 | EMIT6_DISP_LH(0xe3000000, 0x0004, dst_reg, src_reg, REG_0, off); |
| 929 | break; |
| 930 | /* |
| 931 | * BPF_JMP / CALL |
| 932 | */ |
| 933 | case BPF_JMP | BPF_CALL: |
| 934 | { |
| 935 | /* |
| 936 | * b0 = (__bpf_call_base + imm)(b1, b2, b3, b4, b5) |
| 937 | */ |
| 938 | const u64 func = (u64)__bpf_call_base + imm; |
| 939 | |
| 940 | REG_SET_SEEN(BPF_REG_5); |
| 941 | jit->seen |= SEEN_FUNC; |
| 942 | /* lg %w1,<d(imm)>(%l) */ |
| 943 | EMIT6_DISP(0xe3000000, 0x0004, REG_W1, REG_0, REG_L, |
| 944 | EMIT_CONST_U64(func)); |
| 945 | /* basr %r14,%w1 */ |
| 946 | EMIT2(0x0d00, REG_14, REG_W1); |
| 947 | /* lgr %b0,%r2: load return value into %b0 */ |
| 948 | EMIT4(0xb9040000, BPF_REG_0, REG_2); |
| 949 | break; |
| 950 | } |
| 951 | case BPF_JMP | BPF_EXIT: /* return b0 */ |
| 952 | last = (i == fp->len - 1) ? 1 : 0; |
| 953 | if (last && !(jit->seen & SEEN_RET0)) |
| 954 | break; |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 955 | /* j <exit> */ |
| 956 | EMIT4_PCREL(0xa7f40000, jit->exit_ip - jit->prg); |
| 957 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 958 | /* |
| 959 | * Branch relative (number of skipped instructions) to offset on |
| 960 | * condition. |
| 961 | * |
| 962 | * Condition code to mask mapping: |
| 963 | * |
| 964 | * CC | Description | Mask |
| 965 | * ------------------------------ |
| 966 | * 0 | Operands equal | 8 |
| 967 | * 1 | First operand low | 4 |
| 968 | * 2 | First operand high | 2 |
| 969 | * 3 | Unused | 1 |
| 970 | * |
| 971 | * For s390x relative branches: ip = ip + off_bytes |
| 972 | * For BPF relative branches: insn = insn + off_insns + 1 |
| 973 | * |
| 974 | * For example for s390x with offset 0 we jump to the branch |
| 975 | * instruction itself (loop) and for BPF with offset 0 we |
| 976 | * branch to the instruction behind the branch. |
| 977 | */ |
| 978 | case BPF_JMP | BPF_JA: /* if (true) */ |
| 979 | mask = 0xf000; /* j */ |
| 980 | goto branch_oc; |
| 981 | case BPF_JMP | BPF_JSGT | BPF_K: /* ((s64) dst > (s64) imm) */ |
| 982 | mask = 0x2000; /* jh */ |
| 983 | goto branch_ks; |
| 984 | case BPF_JMP | BPF_JSGE | BPF_K: /* ((s64) dst >= (s64) imm) */ |
| 985 | mask = 0xa000; /* jhe */ |
| 986 | goto branch_ks; |
| 987 | case BPF_JMP | BPF_JGT | BPF_K: /* (dst_reg > imm) */ |
| 988 | mask = 0x2000; /* jh */ |
| 989 | goto branch_ku; |
| 990 | case BPF_JMP | BPF_JGE | BPF_K: /* (dst_reg >= imm) */ |
| 991 | mask = 0xa000; /* jhe */ |
| 992 | goto branch_ku; |
| 993 | case BPF_JMP | BPF_JNE | BPF_K: /* (dst_reg != imm) */ |
| 994 | mask = 0x7000; /* jne */ |
| 995 | goto branch_ku; |
| 996 | case BPF_JMP | BPF_JEQ | BPF_K: /* (dst_reg == imm) */ |
| 997 | mask = 0x8000; /* je */ |
| 998 | goto branch_ku; |
| 999 | case BPF_JMP | BPF_JSET | BPF_K: /* (dst_reg & imm) */ |
| 1000 | mask = 0x7000; /* jnz */ |
| 1001 | /* lgfi %w1,imm (load sign extend imm) */ |
| 1002 | EMIT6_IMM(0xc0010000, REG_W1, imm); |
| 1003 | /* ngr %w1,%dst */ |
| 1004 | EMIT4(0xb9800000, REG_W1, dst_reg); |
| 1005 | goto branch_oc; |
| 1006 | |
| 1007 | case BPF_JMP | BPF_JSGT | BPF_X: /* ((s64) dst > (s64) src) */ |
| 1008 | mask = 0x2000; /* jh */ |
| 1009 | goto branch_xs; |
| 1010 | case BPF_JMP | BPF_JSGE | BPF_X: /* ((s64) dst >= (s64) src) */ |
| 1011 | mask = 0xa000; /* jhe */ |
| 1012 | goto branch_xs; |
| 1013 | case BPF_JMP | BPF_JGT | BPF_X: /* (dst > src) */ |
| 1014 | mask = 0x2000; /* jh */ |
| 1015 | goto branch_xu; |
| 1016 | case BPF_JMP | BPF_JGE | BPF_X: /* (dst >= src) */ |
| 1017 | mask = 0xa000; /* jhe */ |
| 1018 | goto branch_xu; |
| 1019 | case BPF_JMP | BPF_JNE | BPF_X: /* (dst != src) */ |
| 1020 | mask = 0x7000; /* jne */ |
| 1021 | goto branch_xu; |
| 1022 | case BPF_JMP | BPF_JEQ | BPF_X: /* (dst == src) */ |
| 1023 | mask = 0x8000; /* je */ |
| 1024 | goto branch_xu; |
| 1025 | case BPF_JMP | BPF_JSET | BPF_X: /* (dst & src) */ |
| 1026 | mask = 0x7000; /* jnz */ |
| 1027 | /* ngrk %w1,%dst,%src */ |
| 1028 | EMIT4_RRF(0xb9e40000, REG_W1, dst_reg, src_reg); |
| 1029 | goto branch_oc; |
| 1030 | branch_ks: |
| 1031 | /* lgfi %w1,imm (load sign extend imm) */ |
| 1032 | EMIT6_IMM(0xc0010000, REG_W1, imm); |
| 1033 | /* cgrj %dst,%w1,mask,off */ |
| 1034 | EMIT6_PCREL(0xec000000, 0x0064, dst_reg, REG_W1, i, off, mask); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1035 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1036 | branch_ku: |
| 1037 | /* lgfi %w1,imm (load sign extend imm) */ |
| 1038 | EMIT6_IMM(0xc0010000, REG_W1, imm); |
| 1039 | /* clgrj %dst,%w1,mask,off */ |
| 1040 | EMIT6_PCREL(0xec000000, 0x0065, dst_reg, REG_W1, i, off, mask); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1041 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1042 | branch_xs: |
| 1043 | /* cgrj %dst,%src,mask,off */ |
| 1044 | EMIT6_PCREL(0xec000000, 0x0064, dst_reg, src_reg, i, off, mask); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1045 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1046 | branch_xu: |
| 1047 | /* clgrj %dst,%src,mask,off */ |
| 1048 | EMIT6_PCREL(0xec000000, 0x0065, dst_reg, src_reg, i, off, mask); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1049 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1050 | branch_oc: |
| 1051 | /* brc mask,jmp_off (branch instruction needs 4 bytes) */ |
| 1052 | jmp_off = addrs[i + off + 1] - (addrs[i + 1] - 4); |
| 1053 | EMIT4_PCREL(0xa7040000 | mask << 8, jmp_off); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1054 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1055 | /* |
| 1056 | * BPF_LD |
| 1057 | */ |
| 1058 | case BPF_LD | BPF_ABS | BPF_B: /* b0 = *(u8 *) (skb->data+imm) */ |
| 1059 | case BPF_LD | BPF_IND | BPF_B: /* b0 = *(u8 *) (skb->data+imm+src) */ |
| 1060 | if ((BPF_MODE(insn->code) == BPF_ABS) && (imm >= 0)) |
| 1061 | func_addr = __pa(sk_load_byte_pos); |
| 1062 | else |
| 1063 | func_addr = __pa(sk_load_byte); |
| 1064 | goto call_fn; |
| 1065 | case BPF_LD | BPF_ABS | BPF_H: /* b0 = *(u16 *) (skb->data+imm) */ |
| 1066 | case BPF_LD | BPF_IND | BPF_H: /* b0 = *(u16 *) (skb->data+imm+src) */ |
| 1067 | if ((BPF_MODE(insn->code) == BPF_ABS) && (imm >= 0)) |
| 1068 | func_addr = __pa(sk_load_half_pos); |
| 1069 | else |
| 1070 | func_addr = __pa(sk_load_half); |
| 1071 | goto call_fn; |
| 1072 | case BPF_LD | BPF_ABS | BPF_W: /* b0 = *(u32 *) (skb->data+imm) */ |
| 1073 | case BPF_LD | BPF_IND | BPF_W: /* b0 = *(u32 *) (skb->data+imm+src) */ |
| 1074 | if ((BPF_MODE(insn->code) == BPF_ABS) && (imm >= 0)) |
| 1075 | func_addr = __pa(sk_load_word_pos); |
| 1076 | else |
| 1077 | func_addr = __pa(sk_load_word); |
| 1078 | goto call_fn; |
| 1079 | call_fn: |
| 1080 | jit->seen |= SEEN_SKB | SEEN_RET0 | SEEN_FUNC; |
| 1081 | REG_SET_SEEN(REG_14); /* Return address of possible func call */ |
| 1082 | |
| 1083 | /* |
| 1084 | * Implicit input: |
| 1085 | * BPF_REG_6 (R7) : skb pointer |
| 1086 | * REG_SKB_DATA (R12): skb data pointer |
| 1087 | * |
| 1088 | * Calculated input: |
| 1089 | * BPF_REG_2 (R3) : offset of byte(s) to fetch in skb |
| 1090 | * BPF_REG_5 (R6) : return address |
| 1091 | * |
| 1092 | * Output: |
| 1093 | * BPF_REG_0 (R14): data read from skb |
| 1094 | * |
| 1095 | * Scratch registers (BPF_REG_1-5) |
| 1096 | */ |
| 1097 | |
| 1098 | /* Call function: llilf %w1,func_addr */ |
| 1099 | EMIT6_IMM(0xc00f0000, REG_W1, func_addr); |
| 1100 | |
| 1101 | /* Offset: lgfi %b2,imm */ |
| 1102 | EMIT6_IMM(0xc0010000, BPF_REG_2, imm); |
| 1103 | if (BPF_MODE(insn->code) == BPF_IND) |
| 1104 | /* agfr %b2,%src (%src is s32 here) */ |
| 1105 | EMIT4(0xb9180000, BPF_REG_2, src_reg); |
| 1106 | |
| 1107 | /* basr %b5,%w1 (%b5 is call saved) */ |
| 1108 | EMIT2(0x0d00, BPF_REG_5, REG_W1); |
| 1109 | |
| 1110 | /* |
| 1111 | * Note: For fast access we jump directly after the |
| 1112 | * jnz instruction from bpf_jit.S |
| 1113 | */ |
| 1114 | /* jnz <ret0> */ |
| 1115 | EMIT4_PCREL(0xa7740000, jit->ret0_ip - jit->prg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1116 | break; |
| 1117 | default: /* too complex, give up */ |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1118 | pr_err("Unknown opcode %02x\n", insn->code); |
| 1119 | return -1; |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1120 | } |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1121 | return insn_count; |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1122 | } |
| 1123 | |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1124 | /* |
| 1125 | * Compile eBPF program into s390x code |
| 1126 | */ |
| 1127 | static int bpf_jit_prog(struct bpf_jit *jit, struct bpf_prog *fp) |
| 1128 | { |
| 1129 | int i, insn_count; |
| 1130 | |
| 1131 | jit->lit = jit->lit_start; |
| 1132 | jit->prg = 0; |
| 1133 | |
| 1134 | bpf_jit_prologue(jit); |
| 1135 | for (i = 0; i < fp->len; i += insn_count) { |
| 1136 | insn_count = bpf_jit_insn(jit, fp, i); |
| 1137 | if (insn_count < 0) |
| 1138 | return -1; |
| 1139 | jit->addrs[i + 1] = jit->prg; /* Next instruction address */ |
| 1140 | } |
| 1141 | bpf_jit_epilogue(jit); |
| 1142 | |
| 1143 | jit->lit_start = jit->prg; |
| 1144 | jit->size = jit->lit; |
| 1145 | jit->size_prg = jit->prg; |
| 1146 | return 0; |
| 1147 | } |
| 1148 | |
| 1149 | /* |
| 1150 | * Classic BPF function stub. BPF programs will be converted into |
| 1151 | * eBPF and then bpf_int_jit_compile() will be called. |
| 1152 | */ |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 1153 | void bpf_jit_compile(struct bpf_prog *fp) |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1154 | { |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1155 | } |
| 1156 | |
| 1157 | /* |
| 1158 | * Compile eBPF program "fp" |
| 1159 | */ |
| 1160 | void bpf_int_jit_compile(struct bpf_prog *fp) |
| 1161 | { |
| 1162 | struct bpf_binary_header *header; |
| 1163 | struct bpf_jit jit; |
| 1164 | int pass; |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1165 | |
| 1166 | if (!bpf_jit_enable) |
| 1167 | return; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1168 | memset(&jit, 0, sizeof(jit)); |
| 1169 | jit.addrs = kcalloc(fp->len + 1, sizeof(*jit.addrs), GFP_KERNEL); |
| 1170 | if (jit.addrs == NULL) |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1171 | return; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1172 | /* |
| 1173 | * Three initial passes: |
| 1174 | * - 1/2: Determine clobbered registers |
| 1175 | * - 3: Calculate program size and addrs arrray |
| 1176 | */ |
| 1177 | for (pass = 1; pass <= 3; pass++) { |
| 1178 | if (bpf_jit_prog(&jit, fp)) |
| 1179 | goto free_addrs; |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1180 | } |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1181 | /* |
| 1182 | * Final pass: Allocate and generate program |
| 1183 | */ |
| 1184 | if (jit.size >= BPF_SIZE_MAX) |
| 1185 | goto free_addrs; |
| 1186 | header = bpf_jit_binary_alloc(jit.size, &jit.prg_buf, 2, jit_fill_hole); |
| 1187 | if (!header) |
| 1188 | goto free_addrs; |
| 1189 | if (bpf_jit_prog(&jit, fp)) |
| 1190 | goto free_addrs; |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1191 | if (bpf_jit_enable > 1) { |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1192 | bpf_jit_dump(fp->len, jit.size, pass, jit.prg_buf); |
| 1193 | if (jit.prg_buf) |
| 1194 | print_fn_code(jit.prg_buf, jit.size_prg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1195 | } |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1196 | if (jit.prg_buf) { |
Heiko Carstens | aa2d2c7 | 2013-07-16 13:25:49 +0200 | [diff] [blame] | 1197 | set_memory_ro((unsigned long)header, header->pages); |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1198 | fp->bpf_func = (void *) jit.prg_buf; |
Daniel Borkmann | 286aad3 | 2014-09-08 08:04:49 +0200 | [diff] [blame] | 1199 | fp->jited = true; |
Heiko Carstens | aa2d2c7 | 2013-07-16 13:25:49 +0200 | [diff] [blame] | 1200 | } |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1201 | free_addrs: |
| 1202 | kfree(jit.addrs); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1203 | } |
| 1204 | |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1205 | /* |
| 1206 | * Free eBPF program |
| 1207 | */ |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 1208 | void bpf_jit_free(struct bpf_prog *fp) |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1209 | { |
Heiko Carstens | aa2d2c7 | 2013-07-16 13:25:49 +0200 | [diff] [blame] | 1210 | unsigned long addr = (unsigned long)fp->bpf_func & PAGE_MASK; |
| 1211 | struct bpf_binary_header *header = (void *)addr; |
| 1212 | |
Daniel Borkmann | f8bbbfc | 2014-03-28 18:58:18 +0100 | [diff] [blame] | 1213 | if (!fp->jited) |
Alexei Starovoitov | d45ed4a | 2013-10-04 00:14:06 -0700 | [diff] [blame] | 1214 | goto free_filter; |
Daniel Borkmann | f8bbbfc | 2014-03-28 18:58:18 +0100 | [diff] [blame] | 1215 | |
Heiko Carstens | aa2d2c7 | 2013-07-16 13:25:49 +0200 | [diff] [blame] | 1216 | set_memory_rw(addr, header->pages); |
Daniel Borkmann | 738cbe7 | 2014-09-08 08:04:47 +0200 | [diff] [blame] | 1217 | bpf_jit_binary_free(header); |
Daniel Borkmann | f8bbbfc | 2014-03-28 18:58:18 +0100 | [diff] [blame] | 1218 | |
Alexei Starovoitov | d45ed4a | 2013-10-04 00:14:06 -0700 | [diff] [blame] | 1219 | free_filter: |
Daniel Borkmann | 60a3b22 | 2014-09-02 22:53:44 +0200 | [diff] [blame] | 1220 | bpf_prog_unlock_free(fp); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1221 | } |