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> |
Michael Holzheu | 6651ee0 | 2015-06-08 21:51:06 -0700 | [diff] [blame] | 24 | #include <linux/bpf.h> |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 25 | #include <asm/cacheflush.h> |
Heiko Carstens | 0f20822 | 2013-09-13 13:36:25 +0200 | [diff] [blame] | 26 | #include <asm/dis.h> |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 27 | #include "bpf_jit.h" |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 28 | |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 29 | int bpf_jit_enable __read_mostly; |
| 30 | |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 31 | struct bpf_jit { |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 32 | u32 seen; /* Flags to remember seen eBPF instructions */ |
| 33 | u32 seen_reg[16]; /* Array to remember which registers are used */ |
| 34 | u32 *addrs; /* Array with relative instruction addresses */ |
| 35 | u8 *prg_buf; /* Start of program */ |
| 36 | int size; /* Size of program and literal pool */ |
| 37 | int size_prg; /* Size of program */ |
| 38 | int prg; /* Current position in program */ |
| 39 | int lit_start; /* Start of literal pool */ |
| 40 | int lit; /* Current position in literal pool */ |
| 41 | int base_ip; /* Base address for literal pool */ |
| 42 | int ret0_ip; /* Address of return 0 */ |
| 43 | int exit_ip; /* Address of exit */ |
Michael Holzheu | 6651ee0 | 2015-06-08 21:51:06 -0700 | [diff] [blame] | 44 | int tail_call_start; /* Tail call start offset */ |
| 45 | int labels[1]; /* Labels for local jumps */ |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 46 | }; |
| 47 | |
Michael Holzheu | ce2b6ad | 2015-07-29 21:15:16 +0200 | [diff] [blame] | 48 | #define BPF_SIZE_MAX 0x7ffff /* Max size for program (20 bit signed displ) */ |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 49 | |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 50 | #define SEEN_SKB 1 /* skb access */ |
| 51 | #define SEEN_MEM 2 /* use mem[] for temporary storage */ |
| 52 | #define SEEN_RET0 4 /* ret0_ip points to a valid return 0 */ |
| 53 | #define SEEN_LITERAL 8 /* code uses literals */ |
| 54 | #define SEEN_FUNC 16 /* calls C functions */ |
Michael Holzheu | 6651ee0 | 2015-06-08 21:51:06 -0700 | [diff] [blame] | 55 | #define SEEN_TAIL_CALL 32 /* code uses tail calls */ |
Michael Holzheu | 9db7f2b | 2015-07-29 21:15:18 +0200 | [diff] [blame] | 56 | #define SEEN_SKB_CHANGE 64 /* code changes skb data */ |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 57 | #define SEEN_STACK (SEEN_FUNC | SEEN_MEM | SEEN_SKB) |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 58 | |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 59 | /* |
| 60 | * s390 registers |
| 61 | */ |
| 62 | #define REG_W0 (__MAX_BPF_REG+0) /* Work register 1 (even) */ |
| 63 | #define REG_W1 (__MAX_BPF_REG+1) /* Work register 2 (odd) */ |
| 64 | #define REG_SKB_DATA (__MAX_BPF_REG+2) /* SKB data register */ |
| 65 | #define REG_L (__MAX_BPF_REG+3) /* Literal pool register */ |
| 66 | #define REG_15 (__MAX_BPF_REG+4) /* Register 15 */ |
| 67 | #define REG_0 REG_W0 /* Register 0 */ |
Michael Holzheu | 6651ee0 | 2015-06-08 21:51:06 -0700 | [diff] [blame] | 68 | #define REG_1 REG_W1 /* Register 1 */ |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 69 | #define REG_2 BPF_REG_1 /* Register 2 */ |
| 70 | #define REG_14 BPF_REG_0 /* Register 14 */ |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 71 | |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 72 | /* |
| 73 | * Mapping of BPF registers to s390 registers |
| 74 | */ |
| 75 | static const int reg2hex[] = { |
| 76 | /* Return code */ |
| 77 | [BPF_REG_0] = 14, |
| 78 | /* Function parameters */ |
| 79 | [BPF_REG_1] = 2, |
| 80 | [BPF_REG_2] = 3, |
| 81 | [BPF_REG_3] = 4, |
| 82 | [BPF_REG_4] = 5, |
| 83 | [BPF_REG_5] = 6, |
| 84 | /* Call saved registers */ |
| 85 | [BPF_REG_6] = 7, |
| 86 | [BPF_REG_7] = 8, |
| 87 | [BPF_REG_8] = 9, |
| 88 | [BPF_REG_9] = 10, |
| 89 | /* BPF stack pointer */ |
| 90 | [BPF_REG_FP] = 13, |
| 91 | /* SKB data pointer */ |
| 92 | [REG_SKB_DATA] = 12, |
| 93 | /* Work registers for s390x backend */ |
| 94 | [REG_W0] = 0, |
| 95 | [REG_W1] = 1, |
| 96 | [REG_L] = 11, |
| 97 | [REG_15] = 15, |
| 98 | }; |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 99 | |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 100 | static inline u32 reg(u32 dst_reg, u32 src_reg) |
Daniel Borkmann | 738cbe7 | 2014-09-08 08:04:47 +0200 | [diff] [blame] | 101 | { |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 102 | return reg2hex[dst_reg] << 4 | reg2hex[src_reg]; |
| 103 | } |
| 104 | |
| 105 | static inline u32 reg_high(u32 reg) |
| 106 | { |
| 107 | return reg2hex[reg] << 4; |
| 108 | } |
| 109 | |
| 110 | static inline void reg_set_seen(struct bpf_jit *jit, u32 b1) |
| 111 | { |
| 112 | u32 r1 = reg2hex[b1]; |
| 113 | |
| 114 | if (!jit->seen_reg[r1] && r1 >= 6 && r1 <= 15) |
| 115 | jit->seen_reg[r1] = 1; |
| 116 | } |
| 117 | |
| 118 | #define REG_SET_SEEN(b1) \ |
| 119 | ({ \ |
| 120 | reg_set_seen(jit, b1); \ |
| 121 | }) |
| 122 | |
| 123 | #define REG_SEEN(b1) jit->seen_reg[reg2hex[(b1)]] |
| 124 | |
| 125 | /* |
| 126 | * EMIT macros for code generation |
| 127 | */ |
| 128 | |
| 129 | #define _EMIT2(op) \ |
| 130 | ({ \ |
| 131 | if (jit->prg_buf) \ |
| 132 | *(u16 *) (jit->prg_buf + jit->prg) = op; \ |
| 133 | jit->prg += 2; \ |
| 134 | }) |
| 135 | |
| 136 | #define EMIT2(op, b1, b2) \ |
| 137 | ({ \ |
| 138 | _EMIT2(op | reg(b1, b2)); \ |
| 139 | REG_SET_SEEN(b1); \ |
| 140 | REG_SET_SEEN(b2); \ |
| 141 | }) |
| 142 | |
| 143 | #define _EMIT4(op) \ |
| 144 | ({ \ |
| 145 | if (jit->prg_buf) \ |
| 146 | *(u32 *) (jit->prg_buf + jit->prg) = op; \ |
| 147 | jit->prg += 4; \ |
| 148 | }) |
| 149 | |
| 150 | #define EMIT4(op, b1, b2) \ |
| 151 | ({ \ |
| 152 | _EMIT4(op | reg(b1, b2)); \ |
| 153 | REG_SET_SEEN(b1); \ |
| 154 | REG_SET_SEEN(b2); \ |
| 155 | }) |
| 156 | |
| 157 | #define EMIT4_RRF(op, b1, b2, b3) \ |
| 158 | ({ \ |
| 159 | _EMIT4(op | reg_high(b3) << 8 | reg(b1, b2)); \ |
| 160 | REG_SET_SEEN(b1); \ |
| 161 | REG_SET_SEEN(b2); \ |
| 162 | REG_SET_SEEN(b3); \ |
| 163 | }) |
| 164 | |
| 165 | #define _EMIT4_DISP(op, disp) \ |
| 166 | ({ \ |
| 167 | unsigned int __disp = (disp) & 0xfff; \ |
| 168 | _EMIT4(op | __disp); \ |
| 169 | }) |
| 170 | |
| 171 | #define EMIT4_DISP(op, b1, b2, disp) \ |
| 172 | ({ \ |
| 173 | _EMIT4_DISP(op | reg_high(b1) << 16 | \ |
| 174 | reg_high(b2) << 8, disp); \ |
| 175 | REG_SET_SEEN(b1); \ |
| 176 | REG_SET_SEEN(b2); \ |
| 177 | }) |
| 178 | |
| 179 | #define EMIT4_IMM(op, b1, imm) \ |
| 180 | ({ \ |
| 181 | unsigned int __imm = (imm) & 0xffff; \ |
| 182 | _EMIT4(op | reg_high(b1) << 16 | __imm); \ |
| 183 | REG_SET_SEEN(b1); \ |
| 184 | }) |
| 185 | |
| 186 | #define EMIT4_PCREL(op, pcrel) \ |
| 187 | ({ \ |
| 188 | long __pcrel = ((pcrel) >> 1) & 0xffff; \ |
| 189 | _EMIT4(op | __pcrel); \ |
| 190 | }) |
| 191 | |
| 192 | #define _EMIT6(op1, op2) \ |
| 193 | ({ \ |
| 194 | if (jit->prg_buf) { \ |
| 195 | *(u32 *) (jit->prg_buf + jit->prg) = op1; \ |
| 196 | *(u16 *) (jit->prg_buf + jit->prg + 4) = op2; \ |
| 197 | } \ |
| 198 | jit->prg += 6; \ |
| 199 | }) |
| 200 | |
| 201 | #define _EMIT6_DISP(op1, op2, disp) \ |
| 202 | ({ \ |
| 203 | unsigned int __disp = (disp) & 0xfff; \ |
| 204 | _EMIT6(op1 | __disp, op2); \ |
| 205 | }) |
| 206 | |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 207 | #define _EMIT6_DISP_LH(op1, op2, disp) \ |
| 208 | ({ \ |
Michael Holzheu | 1df03ff | 2015-07-29 21:15:15 +0200 | [diff] [blame] | 209 | u32 _disp = (u32) disp; \ |
| 210 | unsigned int __disp_h = _disp & 0xff000; \ |
| 211 | unsigned int __disp_l = _disp & 0x00fff; \ |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 212 | _EMIT6(op1 | __disp_l, op2 | __disp_h >> 4); \ |
| 213 | }) |
| 214 | |
| 215 | #define EMIT6_DISP_LH(op1, op2, b1, b2, b3, disp) \ |
| 216 | ({ \ |
| 217 | _EMIT6_DISP_LH(op1 | reg(b1, b2) << 16 | \ |
| 218 | reg_high(b3) << 8, op2, disp); \ |
| 219 | REG_SET_SEEN(b1); \ |
| 220 | REG_SET_SEEN(b2); \ |
| 221 | REG_SET_SEEN(b3); \ |
| 222 | }) |
| 223 | |
Michael Holzheu | 6651ee0 | 2015-06-08 21:51:06 -0700 | [diff] [blame] | 224 | #define EMIT6_PCREL_LABEL(op1, op2, b1, b2, label, mask) \ |
| 225 | ({ \ |
| 226 | int rel = (jit->labels[label] - jit->prg) >> 1; \ |
| 227 | _EMIT6(op1 | reg(b1, b2) << 16 | (rel & 0xffff), \ |
| 228 | op2 | mask << 12); \ |
| 229 | REG_SET_SEEN(b1); \ |
| 230 | REG_SET_SEEN(b2); \ |
| 231 | }) |
| 232 | |
| 233 | #define EMIT6_PCREL_IMM_LABEL(op1, op2, b1, imm, label, mask) \ |
| 234 | ({ \ |
| 235 | int rel = (jit->labels[label] - jit->prg) >> 1; \ |
| 236 | _EMIT6(op1 | (reg_high(b1) | mask) << 16 | \ |
| 237 | (rel & 0xffff), op2 | (imm & 0xff) << 8); \ |
| 238 | REG_SET_SEEN(b1); \ |
| 239 | BUILD_BUG_ON(((unsigned long) imm) > 0xff); \ |
| 240 | }) |
| 241 | |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 242 | #define EMIT6_PCREL(op1, op2, b1, b2, i, off, mask) \ |
| 243 | ({ \ |
| 244 | /* Branch instruction needs 6 bytes */ \ |
| 245 | int rel = (addrs[i + off + 1] - (addrs[i + 1] - 6)) / 2;\ |
Michael Holzheu | b035b60 | 2015-05-21 15:39:31 +0200 | [diff] [blame] | 246 | _EMIT6(op1 | reg(b1, b2) << 16 | (rel & 0xffff), op2 | mask); \ |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 247 | REG_SET_SEEN(b1); \ |
| 248 | REG_SET_SEEN(b2); \ |
| 249 | }) |
| 250 | |
| 251 | #define _EMIT6_IMM(op, imm) \ |
| 252 | ({ \ |
| 253 | unsigned int __imm = (imm); \ |
| 254 | _EMIT6(op | (__imm >> 16), __imm & 0xffff); \ |
| 255 | }) |
| 256 | |
| 257 | #define EMIT6_IMM(op, b1, imm) \ |
| 258 | ({ \ |
| 259 | _EMIT6_IMM(op | reg_high(b1) << 16, imm); \ |
| 260 | REG_SET_SEEN(b1); \ |
| 261 | }) |
| 262 | |
| 263 | #define EMIT_CONST_U32(val) \ |
| 264 | ({ \ |
| 265 | unsigned int ret; \ |
| 266 | ret = jit->lit - jit->base_ip; \ |
| 267 | jit->seen |= SEEN_LITERAL; \ |
| 268 | if (jit->prg_buf) \ |
| 269 | *(u32 *) (jit->prg_buf + jit->lit) = (u32) val; \ |
| 270 | jit->lit += 4; \ |
| 271 | ret; \ |
| 272 | }) |
| 273 | |
| 274 | #define EMIT_CONST_U64(val) \ |
| 275 | ({ \ |
| 276 | unsigned int ret; \ |
| 277 | ret = jit->lit - jit->base_ip; \ |
| 278 | jit->seen |= SEEN_LITERAL; \ |
| 279 | if (jit->prg_buf) \ |
| 280 | *(u64 *) (jit->prg_buf + jit->lit) = (u64) val; \ |
| 281 | jit->lit += 8; \ |
| 282 | ret; \ |
| 283 | }) |
| 284 | |
| 285 | #define EMIT_ZERO(b1) \ |
| 286 | ({ \ |
| 287 | /* llgfr %dst,%dst (zero extend to 64 bit) */ \ |
| 288 | EMIT4(0xb9160000, b1, b1); \ |
| 289 | REG_SET_SEEN(b1); \ |
| 290 | }) |
| 291 | |
| 292 | /* |
| 293 | * Fill whole space with illegal instructions |
| 294 | */ |
| 295 | static void jit_fill_hole(void *area, unsigned int size) |
| 296 | { |
Daniel Borkmann | 738cbe7 | 2014-09-08 08:04:47 +0200 | [diff] [blame] | 297 | memset(area, 0, size); |
| 298 | } |
| 299 | |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 300 | /* |
| 301 | * Save registers from "rs" (register start) to "re" (register end) on stack |
| 302 | */ |
| 303 | static void save_regs(struct bpf_jit *jit, u32 rs, u32 re) |
| 304 | { |
Michael Holzheu | 6651ee0 | 2015-06-08 21:51:06 -0700 | [diff] [blame] | 305 | u32 off = STK_OFF_R6 + (rs - 6) * 8; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 306 | |
| 307 | if (rs == re) |
| 308 | /* stg %rs,off(%r15) */ |
| 309 | _EMIT6(0xe300f000 | rs << 20 | off, 0x0024); |
| 310 | else |
| 311 | /* stmg %rs,%re,off(%r15) */ |
| 312 | _EMIT6_DISP(0xeb00f000 | rs << 20 | re << 16, 0x0024, off); |
| 313 | } |
| 314 | |
| 315 | /* |
| 316 | * Restore registers from "rs" (register start) to "re" (register end) on stack |
| 317 | */ |
| 318 | static void restore_regs(struct bpf_jit *jit, u32 rs, u32 re) |
| 319 | { |
Michael Holzheu | 6651ee0 | 2015-06-08 21:51:06 -0700 | [diff] [blame] | 320 | u32 off = STK_OFF_R6 + (rs - 6) * 8; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 321 | |
| 322 | if (jit->seen & SEEN_STACK) |
| 323 | off += STK_OFF; |
| 324 | |
| 325 | if (rs == re) |
| 326 | /* lg %rs,off(%r15) */ |
| 327 | _EMIT6(0xe300f000 | rs << 20 | off, 0x0004); |
| 328 | else |
| 329 | /* lmg %rs,%re,off(%r15) */ |
| 330 | _EMIT6_DISP(0xeb00f000 | rs << 20 | re << 16, 0x0004, off); |
| 331 | } |
| 332 | |
| 333 | /* |
| 334 | * Return first seen register (from start) |
| 335 | */ |
| 336 | static int get_start(struct bpf_jit *jit, int start) |
| 337 | { |
| 338 | int i; |
| 339 | |
| 340 | for (i = start; i <= 15; i++) { |
| 341 | if (jit->seen_reg[i]) |
| 342 | return i; |
| 343 | } |
| 344 | return 0; |
| 345 | } |
| 346 | |
| 347 | /* |
| 348 | * Return last seen register (from start) (gap >= 2) |
| 349 | */ |
| 350 | static int get_end(struct bpf_jit *jit, int start) |
| 351 | { |
| 352 | int i; |
| 353 | |
| 354 | for (i = start; i < 15; i++) { |
| 355 | if (!jit->seen_reg[i] && !jit->seen_reg[i + 1]) |
| 356 | return i - 1; |
| 357 | } |
| 358 | return jit->seen_reg[15] ? 15 : 14; |
| 359 | } |
| 360 | |
| 361 | #define REGS_SAVE 1 |
| 362 | #define REGS_RESTORE 0 |
| 363 | /* |
| 364 | * Save and restore clobbered registers (6-15) on stack. |
| 365 | * We save/restore registers in chunks with gap >= 2 registers. |
| 366 | */ |
| 367 | static void save_restore_regs(struct bpf_jit *jit, int op) |
| 368 | { |
| 369 | |
| 370 | int re = 6, rs; |
| 371 | |
| 372 | do { |
| 373 | rs = get_start(jit, re); |
| 374 | if (!rs) |
| 375 | break; |
| 376 | re = get_end(jit, rs + 1); |
| 377 | if (op == REGS_SAVE) |
| 378 | save_regs(jit, rs, re); |
| 379 | else |
| 380 | restore_regs(jit, rs, re); |
| 381 | re++; |
| 382 | } while (re <= 15); |
| 383 | } |
| 384 | |
| 385 | /* |
Michael Holzheu | 9db7f2b | 2015-07-29 21:15:18 +0200 | [diff] [blame] | 386 | * For SKB access %b1 contains the SKB pointer. For "bpf_jit.S" |
| 387 | * we store the SKB header length on the stack and the SKB data |
| 388 | * pointer in REG_SKB_DATA. |
| 389 | */ |
| 390 | static void emit_load_skb_data_hlen(struct bpf_jit *jit) |
| 391 | { |
| 392 | /* Header length: llgf %w1,<len>(%b1) */ |
| 393 | EMIT6_DISP_LH(0xe3000000, 0x0016, REG_W1, REG_0, BPF_REG_1, |
| 394 | offsetof(struct sk_buff, len)); |
| 395 | /* s %w1,<data_len>(%b1) */ |
| 396 | EMIT4_DISP(0x5b000000, REG_W1, BPF_REG_1, |
| 397 | offsetof(struct sk_buff, data_len)); |
| 398 | /* stg %w1,ST_OFF_HLEN(%r0,%r15) */ |
| 399 | EMIT6_DISP_LH(0xe3000000, 0x0024, REG_W1, REG_0, REG_15, STK_OFF_HLEN); |
| 400 | /* lg %skb_data,data_off(%b1) */ |
| 401 | EMIT6_DISP_LH(0xe3000000, 0x0004, REG_SKB_DATA, REG_0, |
| 402 | BPF_REG_1, offsetof(struct sk_buff, data)); |
| 403 | } |
| 404 | |
| 405 | /* |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 406 | * Emit function prologue |
| 407 | * |
| 408 | * Save registers and create stack frame if necessary. |
| 409 | * See stack frame layout desription in "bpf_jit.h"! |
| 410 | */ |
Michael Holzheu | cde66c2 | 2015-07-29 21:15:17 +0200 | [diff] [blame] | 411 | static void bpf_jit_prologue(struct bpf_jit *jit, bool is_classic) |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 412 | { |
Michael Holzheu | 6651ee0 | 2015-06-08 21:51:06 -0700 | [diff] [blame] | 413 | if (jit->seen & SEEN_TAIL_CALL) { |
| 414 | /* xc STK_OFF_TCCNT(4,%r15),STK_OFF_TCCNT(%r15) */ |
| 415 | _EMIT6(0xd703f000 | STK_OFF_TCCNT, 0xf000 | STK_OFF_TCCNT); |
| 416 | } else { |
| 417 | /* j tail_call_start: NOP if no tail calls are used */ |
| 418 | EMIT4_PCREL(0xa7f40000, 6); |
| 419 | _EMIT2(0); |
| 420 | } |
| 421 | /* Tail calls have to skip above initialization */ |
| 422 | jit->tail_call_start = jit->prg; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 423 | /* Save registers */ |
| 424 | save_restore_regs(jit, REGS_SAVE); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 425 | /* Setup literal pool */ |
| 426 | if (jit->seen & SEEN_LITERAL) { |
| 427 | /* basr %r13,0 */ |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 428 | EMIT2(0x0d00, REG_L, REG_0); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 429 | jit->base_ip = jit->prg; |
| 430 | } |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 431 | /* Setup stack and backchain */ |
| 432 | if (jit->seen & SEEN_STACK) { |
Michael Holzheu | 88aeca1 | 2015-06-01 22:48:35 -0700 | [diff] [blame] | 433 | if (jit->seen & SEEN_FUNC) |
| 434 | /* lgr %w1,%r15 (backchain) */ |
| 435 | EMIT4(0xb9040000, REG_W1, REG_15); |
| 436 | /* la %bfp,STK_160_UNUSED(%r15) (BPF frame pointer) */ |
| 437 | EMIT4_DISP(0x41000000, BPF_REG_FP, REG_15, STK_160_UNUSED); |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 438 | /* aghi %r15,-STK_OFF */ |
| 439 | EMIT4_IMM(0xa70b0000, REG_15, -STK_OFF); |
| 440 | if (jit->seen & SEEN_FUNC) |
Michael Holzheu | 88aeca1 | 2015-06-01 22:48:35 -0700 | [diff] [blame] | 441 | /* stg %w1,152(%r15) (backchain) */ |
| 442 | EMIT6_DISP_LH(0xe3000000, 0x0024, REG_W1, REG_0, |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 443 | REG_15, 152); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 444 | } |
Michael Holzheu | 9db7f2b | 2015-07-29 21:15:18 +0200 | [diff] [blame] | 445 | if (jit->seen & SEEN_SKB) |
| 446 | emit_load_skb_data_hlen(jit); |
| 447 | if (jit->seen & SEEN_SKB_CHANGE) |
| 448 | /* stg %b1,ST_OFF_SKBP(%r0,%r15) */ |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 449 | EMIT6_DISP_LH(0xe3000000, 0x0024, REG_W1, REG_0, REG_15, |
Michael Holzheu | 9db7f2b | 2015-07-29 21:15:18 +0200 | [diff] [blame] | 450 | STK_OFF_SKBP); |
Michael Holzheu | cde66c2 | 2015-07-29 21:15:17 +0200 | [diff] [blame] | 451 | /* Clear A (%b0) and X (%b7) registers for converted BPF programs */ |
| 452 | if (is_classic) { |
| 453 | if (REG_SEEN(BPF_REG_A)) |
| 454 | /* lghi %ba,0 */ |
| 455 | EMIT4_IMM(0xa7090000, BPF_REG_A, 0); |
| 456 | if (REG_SEEN(BPF_REG_X)) |
| 457 | /* lghi %bx,0 */ |
| 458 | EMIT4_IMM(0xa7090000, BPF_REG_X, 0); |
| 459 | } |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 460 | } |
| 461 | |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 462 | /* |
| 463 | * Function epilogue |
| 464 | */ |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 465 | static void bpf_jit_epilogue(struct bpf_jit *jit) |
| 466 | { |
| 467 | /* Return 0 */ |
| 468 | if (jit->seen & SEEN_RET0) { |
| 469 | jit->ret0_ip = jit->prg; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 470 | /* lghi %b0,0 */ |
| 471 | EMIT4_IMM(0xa7090000, BPF_REG_0, 0); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 472 | } |
| 473 | jit->exit_ip = jit->prg; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 474 | /* Load exit code: lgr %r2,%b0 */ |
| 475 | EMIT4(0xb9040000, REG_2, BPF_REG_0); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 476 | /* Restore registers */ |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 477 | save_restore_regs(jit, REGS_RESTORE); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 478 | /* br %r14 */ |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 479 | _EMIT2(0x07fe); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 480 | } |
| 481 | |
| 482 | /* |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 483 | * Compile one eBPF instruction into s390x code |
Michael Holzheu | b9b4b1c | 2015-04-29 18:45:03 +0200 | [diff] [blame] | 484 | * |
| 485 | * NOTE: Use noinline because for gcov (-fprofile-arcs) gcc allocates a lot of |
| 486 | * stack space for the large switch statement. |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 487 | */ |
Michael Holzheu | b9b4b1c | 2015-04-29 18:45:03 +0200 | [diff] [blame] | 488 | 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] | 489 | { |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 490 | struct bpf_insn *insn = &fp->insnsi[i]; |
| 491 | int jmp_off, last, insn_count = 1; |
| 492 | unsigned int func_addr, mask; |
| 493 | u32 dst_reg = insn->dst_reg; |
| 494 | u32 src_reg = insn->src_reg; |
| 495 | u32 *addrs = jit->addrs; |
| 496 | s32 imm = insn->imm; |
| 497 | s16 off = insn->off; |
| 498 | |
| 499 | switch (insn->code) { |
| 500 | /* |
| 501 | * BPF_MOV |
| 502 | */ |
| 503 | case BPF_ALU | BPF_MOV | BPF_X: /* dst = (u32) src */ |
| 504 | /* llgfr %dst,%src */ |
| 505 | EMIT4(0xb9160000, dst_reg, src_reg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 506 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 507 | case BPF_ALU64 | BPF_MOV | BPF_X: /* dst = src */ |
| 508 | /* lgr %dst,%src */ |
| 509 | EMIT4(0xb9040000, dst_reg, src_reg); |
| 510 | break; |
| 511 | case BPF_ALU | BPF_MOV | BPF_K: /* dst = (u32) imm */ |
| 512 | /* llilf %dst,imm */ |
| 513 | EMIT6_IMM(0xc00f0000, dst_reg, imm); |
| 514 | break; |
| 515 | case BPF_ALU64 | BPF_MOV | BPF_K: /* dst = imm */ |
| 516 | /* lgfi %dst,imm */ |
| 517 | EMIT6_IMM(0xc0010000, dst_reg, imm); |
| 518 | break; |
| 519 | /* |
| 520 | * BPF_LD 64 |
| 521 | */ |
| 522 | case BPF_LD | BPF_IMM | BPF_DW: /* dst = (u64) imm */ |
| 523 | { |
| 524 | /* 16 byte instruction that uses two 'struct bpf_insn' */ |
| 525 | u64 imm64; |
| 526 | |
| 527 | imm64 = (u64)(u32) insn[0].imm | ((u64)(u32) insn[1].imm) << 32; |
| 528 | /* lg %dst,<d(imm)>(%l) */ |
| 529 | EMIT6_DISP_LH(0xe3000000, 0x0004, dst_reg, REG_0, REG_L, |
| 530 | EMIT_CONST_U64(imm64)); |
| 531 | insn_count = 2; |
| 532 | break; |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 533 | } |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 534 | /* |
| 535 | * BPF_ADD |
| 536 | */ |
| 537 | case BPF_ALU | BPF_ADD | BPF_X: /* dst = (u32) dst + (u32) src */ |
| 538 | /* ar %dst,%src */ |
| 539 | EMIT2(0x1a00, dst_reg, src_reg); |
| 540 | EMIT_ZERO(dst_reg); |
| 541 | break; |
| 542 | case BPF_ALU64 | BPF_ADD | BPF_X: /* dst = dst + src */ |
| 543 | /* agr %dst,%src */ |
| 544 | EMIT4(0xb9080000, dst_reg, src_reg); |
| 545 | break; |
| 546 | case BPF_ALU | BPF_ADD | BPF_K: /* dst = (u32) dst + (u32) imm */ |
| 547 | if (!imm) |
| 548 | break; |
| 549 | /* alfi %dst,imm */ |
| 550 | EMIT6_IMM(0xc20b0000, dst_reg, imm); |
| 551 | EMIT_ZERO(dst_reg); |
| 552 | break; |
| 553 | case BPF_ALU64 | BPF_ADD | BPF_K: /* dst = dst + imm */ |
| 554 | if (!imm) |
| 555 | break; |
| 556 | /* agfi %dst,imm */ |
| 557 | EMIT6_IMM(0xc2080000, dst_reg, imm); |
| 558 | break; |
| 559 | /* |
| 560 | * BPF_SUB |
| 561 | */ |
| 562 | case BPF_ALU | BPF_SUB | BPF_X: /* dst = (u32) dst - (u32) src */ |
| 563 | /* sr %dst,%src */ |
| 564 | EMIT2(0x1b00, dst_reg, src_reg); |
| 565 | EMIT_ZERO(dst_reg); |
| 566 | break; |
| 567 | case BPF_ALU64 | BPF_SUB | BPF_X: /* dst = dst - src */ |
| 568 | /* sgr %dst,%src */ |
| 569 | EMIT4(0xb9090000, dst_reg, src_reg); |
| 570 | break; |
| 571 | case BPF_ALU | BPF_SUB | BPF_K: /* dst = (u32) dst - (u32) imm */ |
| 572 | if (!imm) |
| 573 | break; |
| 574 | /* alfi %dst,-imm */ |
| 575 | EMIT6_IMM(0xc20b0000, dst_reg, -imm); |
| 576 | EMIT_ZERO(dst_reg); |
| 577 | break; |
| 578 | case BPF_ALU64 | BPF_SUB | BPF_K: /* dst = dst - imm */ |
| 579 | if (!imm) |
| 580 | break; |
| 581 | /* agfi %dst,-imm */ |
| 582 | EMIT6_IMM(0xc2080000, dst_reg, -imm); |
| 583 | break; |
| 584 | /* |
| 585 | * BPF_MUL |
| 586 | */ |
| 587 | case BPF_ALU | BPF_MUL | BPF_X: /* dst = (u32) dst * (u32) src */ |
| 588 | /* msr %dst,%src */ |
| 589 | EMIT4(0xb2520000, dst_reg, src_reg); |
| 590 | EMIT_ZERO(dst_reg); |
| 591 | break; |
| 592 | case BPF_ALU64 | BPF_MUL | BPF_X: /* dst = dst * src */ |
| 593 | /* msgr %dst,%src */ |
| 594 | EMIT4(0xb90c0000, dst_reg, src_reg); |
| 595 | break; |
| 596 | case BPF_ALU | BPF_MUL | BPF_K: /* dst = (u32) dst * (u32) imm */ |
| 597 | if (imm == 1) |
| 598 | break; |
| 599 | /* msfi %r5,imm */ |
| 600 | EMIT6_IMM(0xc2010000, dst_reg, imm); |
| 601 | EMIT_ZERO(dst_reg); |
| 602 | break; |
| 603 | case BPF_ALU64 | BPF_MUL | BPF_K: /* dst = dst * imm */ |
| 604 | if (imm == 1) |
| 605 | break; |
| 606 | /* msgfi %dst,imm */ |
| 607 | EMIT6_IMM(0xc2000000, dst_reg, imm); |
| 608 | break; |
| 609 | /* |
| 610 | * BPF_DIV / BPF_MOD |
| 611 | */ |
| 612 | case BPF_ALU | BPF_DIV | BPF_X: /* dst = (u32) dst / (u32) src */ |
| 613 | case BPF_ALU | BPF_MOD | BPF_X: /* dst = (u32) dst % (u32) src */ |
| 614 | { |
| 615 | 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] | 616 | |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 617 | jit->seen |= SEEN_RET0; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 618 | /* ltr %src,%src (if src == 0 goto fail) */ |
| 619 | EMIT2(0x1200, src_reg, src_reg); |
| 620 | /* jz <ret0> */ |
| 621 | EMIT4_PCREL(0xa7840000, jit->ret0_ip - jit->prg); |
| 622 | /* lhi %w0,0 */ |
| 623 | EMIT4_IMM(0xa7080000, REG_W0, 0); |
| 624 | /* lr %w1,%dst */ |
| 625 | EMIT2(0x1800, REG_W1, dst_reg); |
| 626 | /* dlr %w0,%src */ |
| 627 | EMIT4(0xb9970000, REG_W0, src_reg); |
| 628 | /* llgfr %dst,%rc */ |
| 629 | EMIT4(0xb9160000, dst_reg, rc_reg); |
| 630 | break; |
| 631 | } |
Michael Holzheu | 771aada | 2015-04-27 11:12:25 +0200 | [diff] [blame] | 632 | case BPF_ALU64 | BPF_DIV | BPF_X: /* dst = dst / src */ |
| 633 | case BPF_ALU64 | BPF_MOD | BPF_X: /* dst = dst % src */ |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 634 | { |
| 635 | int rc_reg = BPF_OP(insn->code) == BPF_DIV ? REG_W1 : REG_W0; |
| 636 | |
| 637 | jit->seen |= SEEN_RET0; |
| 638 | /* ltgr %src,%src (if src == 0 goto fail) */ |
| 639 | EMIT4(0xb9020000, src_reg, src_reg); |
| 640 | /* jz <ret0> */ |
| 641 | EMIT4_PCREL(0xa7840000, jit->ret0_ip - jit->prg); |
| 642 | /* lghi %w0,0 */ |
| 643 | EMIT4_IMM(0xa7090000, REG_W0, 0); |
| 644 | /* lgr %w1,%dst */ |
| 645 | EMIT4(0xb9040000, REG_W1, dst_reg); |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 646 | /* dlgr %w0,%dst */ |
Michael Holzheu | 771aada | 2015-04-27 11:12:25 +0200 | [diff] [blame] | 647 | EMIT4(0xb9870000, REG_W0, src_reg); |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 648 | /* lgr %dst,%rc */ |
| 649 | EMIT4(0xb9040000, dst_reg, rc_reg); |
| 650 | break; |
| 651 | } |
| 652 | case BPF_ALU | BPF_DIV | BPF_K: /* dst = (u32) dst / (u32) imm */ |
| 653 | case BPF_ALU | BPF_MOD | BPF_K: /* dst = (u32) dst % (u32) imm */ |
| 654 | { |
| 655 | int rc_reg = BPF_OP(insn->code) == BPF_DIV ? REG_W1 : REG_W0; |
| 656 | |
| 657 | if (imm == 1) { |
| 658 | if (BPF_OP(insn->code) == BPF_MOD) |
| 659 | /* lhgi %dst,0 */ |
| 660 | EMIT4_IMM(0xa7090000, dst_reg, 0); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 661 | break; |
| 662 | } |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 663 | /* lhi %w0,0 */ |
| 664 | EMIT4_IMM(0xa7080000, REG_W0, 0); |
| 665 | /* lr %w1,%dst */ |
| 666 | EMIT2(0x1800, REG_W1, dst_reg); |
| 667 | /* dl %w0,<d(imm)>(%l) */ |
| 668 | EMIT6_DISP_LH(0xe3000000, 0x0097, REG_W0, REG_0, REG_L, |
| 669 | EMIT_CONST_U32(imm)); |
| 670 | /* llgfr %dst,%rc */ |
| 671 | EMIT4(0xb9160000, dst_reg, rc_reg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 672 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 673 | } |
Michael Holzheu | 771aada | 2015-04-27 11:12:25 +0200 | [diff] [blame] | 674 | case BPF_ALU64 | BPF_DIV | BPF_K: /* dst = dst / imm */ |
| 675 | case BPF_ALU64 | BPF_MOD | BPF_K: /* dst = dst % imm */ |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 676 | { |
| 677 | int rc_reg = BPF_OP(insn->code) == BPF_DIV ? REG_W1 : REG_W0; |
| 678 | |
| 679 | if (imm == 1) { |
| 680 | if (BPF_OP(insn->code) == BPF_MOD) |
| 681 | /* lhgi %dst,0 */ |
| 682 | EMIT4_IMM(0xa7090000, dst_reg, 0); |
| 683 | break; |
| 684 | } |
| 685 | /* lghi %w0,0 */ |
| 686 | EMIT4_IMM(0xa7090000, REG_W0, 0); |
| 687 | /* lgr %w1,%dst */ |
| 688 | EMIT4(0xb9040000, REG_W1, dst_reg); |
| 689 | /* dlg %w0,<d(imm)>(%l) */ |
| 690 | EMIT6_DISP_LH(0xe3000000, 0x0087, REG_W0, REG_0, REG_L, |
Michael Holzheu | 771aada | 2015-04-27 11:12:25 +0200 | [diff] [blame] | 691 | EMIT_CONST_U64(imm)); |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 692 | /* lgr %dst,%rc */ |
| 693 | EMIT4(0xb9040000, dst_reg, rc_reg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 694 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 695 | } |
| 696 | /* |
| 697 | * BPF_AND |
| 698 | */ |
| 699 | case BPF_ALU | BPF_AND | BPF_X: /* dst = (u32) dst & (u32) src */ |
| 700 | /* nr %dst,%src */ |
| 701 | EMIT2(0x1400, dst_reg, src_reg); |
| 702 | EMIT_ZERO(dst_reg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 703 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 704 | case BPF_ALU64 | BPF_AND | BPF_X: /* dst = dst & src */ |
| 705 | /* ngr %dst,%src */ |
| 706 | EMIT4(0xb9800000, dst_reg, src_reg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 707 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 708 | case BPF_ALU | BPF_AND | BPF_K: /* dst = (u32) dst & (u32) imm */ |
| 709 | /* nilf %dst,imm */ |
| 710 | EMIT6_IMM(0xc00b0000, dst_reg, imm); |
| 711 | EMIT_ZERO(dst_reg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 712 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 713 | case BPF_ALU64 | BPF_AND | BPF_K: /* dst = dst & imm */ |
| 714 | /* ng %dst,<d(imm)>(%l) */ |
| 715 | EMIT6_DISP_LH(0xe3000000, 0x0080, dst_reg, REG_0, REG_L, |
| 716 | EMIT_CONST_U64(imm)); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 717 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 718 | /* |
| 719 | * BPF_OR |
| 720 | */ |
| 721 | case BPF_ALU | BPF_OR | BPF_X: /* dst = (u32) dst | (u32) src */ |
| 722 | /* or %dst,%src */ |
| 723 | EMIT2(0x1600, dst_reg, src_reg); |
| 724 | EMIT_ZERO(dst_reg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 725 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 726 | case BPF_ALU64 | BPF_OR | BPF_X: /* dst = dst | src */ |
| 727 | /* ogr %dst,%src */ |
| 728 | EMIT4(0xb9810000, dst_reg, src_reg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 729 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 730 | case BPF_ALU | BPF_OR | BPF_K: /* dst = (u32) dst | (u32) imm */ |
| 731 | /* oilf %dst,imm */ |
| 732 | EMIT6_IMM(0xc00d0000, dst_reg, imm); |
| 733 | EMIT_ZERO(dst_reg); |
| 734 | break; |
| 735 | case BPF_ALU64 | BPF_OR | BPF_K: /* dst = dst | imm */ |
| 736 | /* og %dst,<d(imm)>(%l) */ |
| 737 | EMIT6_DISP_LH(0xe3000000, 0x0081, dst_reg, REG_0, REG_L, |
| 738 | EMIT_CONST_U64(imm)); |
| 739 | break; |
| 740 | /* |
| 741 | * BPF_XOR |
| 742 | */ |
| 743 | case BPF_ALU | BPF_XOR | BPF_X: /* dst = (u32) dst ^ (u32) src */ |
| 744 | /* xr %dst,%src */ |
| 745 | EMIT2(0x1700, dst_reg, src_reg); |
| 746 | EMIT_ZERO(dst_reg); |
| 747 | break; |
| 748 | case BPF_ALU64 | BPF_XOR | BPF_X: /* dst = dst ^ src */ |
| 749 | /* xgr %dst,%src */ |
| 750 | EMIT4(0xb9820000, dst_reg, src_reg); |
| 751 | break; |
| 752 | case BPF_ALU | BPF_XOR | BPF_K: /* dst = (u32) dst ^ (u32) imm */ |
| 753 | if (!imm) |
| 754 | break; |
| 755 | /* xilf %dst,imm */ |
| 756 | EMIT6_IMM(0xc0070000, dst_reg, imm); |
| 757 | EMIT_ZERO(dst_reg); |
| 758 | break; |
| 759 | case BPF_ALU64 | BPF_XOR | BPF_K: /* dst = dst ^ imm */ |
| 760 | /* xg %dst,<d(imm)>(%l) */ |
| 761 | EMIT6_DISP_LH(0xe3000000, 0x0082, dst_reg, REG_0, REG_L, |
| 762 | EMIT_CONST_U64(imm)); |
| 763 | break; |
| 764 | /* |
| 765 | * BPF_LSH |
| 766 | */ |
| 767 | case BPF_ALU | BPF_LSH | BPF_X: /* dst = (u32) dst << (u32) src */ |
| 768 | /* sll %dst,0(%src) */ |
| 769 | EMIT4_DISP(0x89000000, dst_reg, src_reg, 0); |
| 770 | EMIT_ZERO(dst_reg); |
| 771 | break; |
| 772 | case BPF_ALU64 | BPF_LSH | BPF_X: /* dst = dst << src */ |
| 773 | /* sllg %dst,%dst,0(%src) */ |
| 774 | EMIT6_DISP_LH(0xeb000000, 0x000d, dst_reg, dst_reg, src_reg, 0); |
| 775 | break; |
| 776 | case BPF_ALU | BPF_LSH | BPF_K: /* dst = (u32) dst << (u32) imm */ |
| 777 | if (imm == 0) |
| 778 | break; |
| 779 | /* sll %dst,imm(%r0) */ |
| 780 | EMIT4_DISP(0x89000000, dst_reg, REG_0, imm); |
| 781 | EMIT_ZERO(dst_reg); |
| 782 | break; |
| 783 | case BPF_ALU64 | BPF_LSH | BPF_K: /* dst = dst << imm */ |
| 784 | if (imm == 0) |
| 785 | break; |
| 786 | /* sllg %dst,%dst,imm(%r0) */ |
| 787 | EMIT6_DISP_LH(0xeb000000, 0x000d, dst_reg, dst_reg, REG_0, imm); |
| 788 | break; |
| 789 | /* |
| 790 | * BPF_RSH |
| 791 | */ |
| 792 | case BPF_ALU | BPF_RSH | BPF_X: /* dst = (u32) dst >> (u32) src */ |
| 793 | /* srl %dst,0(%src) */ |
| 794 | EMIT4_DISP(0x88000000, dst_reg, src_reg, 0); |
| 795 | EMIT_ZERO(dst_reg); |
| 796 | break; |
| 797 | case BPF_ALU64 | BPF_RSH | BPF_X: /* dst = dst >> src */ |
| 798 | /* srlg %dst,%dst,0(%src) */ |
| 799 | EMIT6_DISP_LH(0xeb000000, 0x000c, dst_reg, dst_reg, src_reg, 0); |
| 800 | break; |
| 801 | case BPF_ALU | BPF_RSH | BPF_K: /* dst = (u32) dst >> (u32) imm */ |
| 802 | if (imm == 0) |
| 803 | break; |
| 804 | /* srl %dst,imm(%r0) */ |
| 805 | EMIT4_DISP(0x88000000, dst_reg, REG_0, imm); |
| 806 | EMIT_ZERO(dst_reg); |
| 807 | break; |
| 808 | case BPF_ALU64 | BPF_RSH | BPF_K: /* dst = dst >> imm */ |
| 809 | if (imm == 0) |
| 810 | break; |
| 811 | /* srlg %dst,%dst,imm(%r0) */ |
| 812 | EMIT6_DISP_LH(0xeb000000, 0x000c, dst_reg, dst_reg, REG_0, imm); |
| 813 | break; |
| 814 | /* |
| 815 | * BPF_ARSH |
| 816 | */ |
| 817 | case BPF_ALU64 | BPF_ARSH | BPF_X: /* ((s64) dst) >>= src */ |
| 818 | /* srag %dst,%dst,0(%src) */ |
| 819 | EMIT6_DISP_LH(0xeb000000, 0x000a, dst_reg, dst_reg, src_reg, 0); |
| 820 | break; |
| 821 | case BPF_ALU64 | BPF_ARSH | BPF_K: /* ((s64) dst) >>= imm */ |
| 822 | if (imm == 0) |
| 823 | break; |
| 824 | /* srag %dst,%dst,imm(%r0) */ |
| 825 | EMIT6_DISP_LH(0xeb000000, 0x000a, dst_reg, dst_reg, REG_0, imm); |
| 826 | break; |
| 827 | /* |
| 828 | * BPF_NEG |
| 829 | */ |
| 830 | case BPF_ALU | BPF_NEG: /* dst = (u32) -dst */ |
| 831 | /* lcr %dst,%dst */ |
| 832 | EMIT2(0x1300, dst_reg, dst_reg); |
| 833 | EMIT_ZERO(dst_reg); |
| 834 | break; |
| 835 | case BPF_ALU64 | BPF_NEG: /* dst = -dst */ |
| 836 | /* lcgr %dst,%dst */ |
| 837 | EMIT4(0xb9130000, dst_reg, dst_reg); |
| 838 | break; |
| 839 | /* |
| 840 | * BPF_FROM_BE/LE |
| 841 | */ |
| 842 | case BPF_ALU | BPF_END | BPF_FROM_BE: |
| 843 | /* s390 is big endian, therefore only clear high order bytes */ |
| 844 | switch (imm) { |
| 845 | case 16: /* dst = (u16) cpu_to_be16(dst) */ |
| 846 | /* llghr %dst,%dst */ |
| 847 | EMIT4(0xb9850000, dst_reg, dst_reg); |
| 848 | break; |
| 849 | case 32: /* dst = (u32) cpu_to_be32(dst) */ |
| 850 | /* llgfr %dst,%dst */ |
| 851 | EMIT4(0xb9160000, dst_reg, dst_reg); |
| 852 | break; |
| 853 | case 64: /* dst = (u64) cpu_to_be64(dst) */ |
| 854 | break; |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 855 | } |
| 856 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 857 | case BPF_ALU | BPF_END | BPF_FROM_LE: |
| 858 | switch (imm) { |
| 859 | case 16: /* dst = (u16) cpu_to_le16(dst) */ |
| 860 | /* lrvr %dst,%dst */ |
| 861 | EMIT4(0xb91f0000, dst_reg, dst_reg); |
| 862 | /* srl %dst,16(%r0) */ |
| 863 | EMIT4_DISP(0x88000000, dst_reg, REG_0, 16); |
| 864 | /* llghr %dst,%dst */ |
| 865 | EMIT4(0xb9850000, dst_reg, dst_reg); |
| 866 | break; |
| 867 | case 32: /* dst = (u32) cpu_to_le32(dst) */ |
| 868 | /* lrvr %dst,%dst */ |
| 869 | EMIT4(0xb91f0000, dst_reg, dst_reg); |
| 870 | /* llgfr %dst,%dst */ |
| 871 | EMIT4(0xb9160000, dst_reg, dst_reg); |
| 872 | break; |
| 873 | case 64: /* dst = (u64) cpu_to_le64(dst) */ |
| 874 | /* lrvgr %dst,%dst */ |
| 875 | EMIT4(0xb90f0000, dst_reg, dst_reg); |
| 876 | break; |
| 877 | } |
| 878 | break; |
| 879 | /* |
| 880 | * BPF_ST(X) |
| 881 | */ |
| 882 | case BPF_STX | BPF_MEM | BPF_B: /* *(u8 *)(dst + off) = src_reg */ |
| 883 | /* stcy %src,off(%dst) */ |
| 884 | EMIT6_DISP_LH(0xe3000000, 0x0072, src_reg, dst_reg, REG_0, off); |
| 885 | jit->seen |= SEEN_MEM; |
| 886 | break; |
| 887 | case BPF_STX | BPF_MEM | BPF_H: /* (u16 *)(dst + off) = src */ |
| 888 | /* sthy %src,off(%dst) */ |
| 889 | EMIT6_DISP_LH(0xe3000000, 0x0070, src_reg, dst_reg, REG_0, off); |
| 890 | jit->seen |= SEEN_MEM; |
| 891 | break; |
| 892 | case BPF_STX | BPF_MEM | BPF_W: /* *(u32 *)(dst + off) = src */ |
| 893 | /* sty %src,off(%dst) */ |
| 894 | EMIT6_DISP_LH(0xe3000000, 0x0050, src_reg, dst_reg, REG_0, off); |
| 895 | jit->seen |= SEEN_MEM; |
| 896 | break; |
| 897 | case BPF_STX | BPF_MEM | BPF_DW: /* (u64 *)(dst + off) = src */ |
| 898 | /* stg %src,off(%dst) */ |
| 899 | EMIT6_DISP_LH(0xe3000000, 0x0024, src_reg, dst_reg, REG_0, off); |
| 900 | jit->seen |= SEEN_MEM; |
| 901 | break; |
| 902 | case BPF_ST | BPF_MEM | BPF_B: /* *(u8 *)(dst + off) = imm */ |
| 903 | /* lhi %w0,imm */ |
| 904 | EMIT4_IMM(0xa7080000, REG_W0, (u8) imm); |
| 905 | /* stcy %w0,off(dst) */ |
| 906 | EMIT6_DISP_LH(0xe3000000, 0x0072, REG_W0, dst_reg, REG_0, off); |
| 907 | jit->seen |= SEEN_MEM; |
| 908 | break; |
| 909 | case BPF_ST | BPF_MEM | BPF_H: /* (u16 *)(dst + off) = imm */ |
| 910 | /* lhi %w0,imm */ |
| 911 | EMIT4_IMM(0xa7080000, REG_W0, (u16) imm); |
| 912 | /* sthy %w0,off(dst) */ |
| 913 | EMIT6_DISP_LH(0xe3000000, 0x0070, REG_W0, dst_reg, REG_0, off); |
| 914 | jit->seen |= SEEN_MEM; |
| 915 | break; |
| 916 | case BPF_ST | BPF_MEM | BPF_W: /* *(u32 *)(dst + off) = imm */ |
| 917 | /* llilf %w0,imm */ |
| 918 | EMIT6_IMM(0xc00f0000, REG_W0, (u32) imm); |
| 919 | /* sty %w0,off(%dst) */ |
| 920 | EMIT6_DISP_LH(0xe3000000, 0x0050, REG_W0, dst_reg, REG_0, off); |
| 921 | jit->seen |= SEEN_MEM; |
| 922 | break; |
| 923 | case BPF_ST | BPF_MEM | BPF_DW: /* *(u64 *)(dst + off) = imm */ |
| 924 | /* lgfi %w0,imm */ |
| 925 | EMIT6_IMM(0xc0010000, REG_W0, imm); |
| 926 | /* stg %w0,off(%dst) */ |
| 927 | EMIT6_DISP_LH(0xe3000000, 0x0024, REG_W0, dst_reg, REG_0, off); |
| 928 | jit->seen |= SEEN_MEM; |
| 929 | break; |
| 930 | /* |
| 931 | * BPF_STX XADD (atomic_add) |
| 932 | */ |
| 933 | case BPF_STX | BPF_XADD | BPF_W: /* *(u32 *)(dst + off) += src */ |
| 934 | /* laal %w0,%src,off(%dst) */ |
| 935 | EMIT6_DISP_LH(0xeb000000, 0x00fa, REG_W0, src_reg, |
| 936 | dst_reg, off); |
| 937 | jit->seen |= SEEN_MEM; |
| 938 | break; |
| 939 | case BPF_STX | BPF_XADD | BPF_DW: /* *(u64 *)(dst + off) += src */ |
| 940 | /* laalg %w0,%src,off(%dst) */ |
| 941 | EMIT6_DISP_LH(0xeb000000, 0x00ea, REG_W0, src_reg, |
| 942 | dst_reg, off); |
| 943 | jit->seen |= SEEN_MEM; |
| 944 | break; |
| 945 | /* |
| 946 | * BPF_LDX |
| 947 | */ |
| 948 | case BPF_LDX | BPF_MEM | BPF_B: /* dst = *(u8 *)(ul) (src + off) */ |
| 949 | /* llgc %dst,0(off,%src) */ |
| 950 | EMIT6_DISP_LH(0xe3000000, 0x0090, dst_reg, src_reg, REG_0, off); |
| 951 | jit->seen |= SEEN_MEM; |
| 952 | break; |
| 953 | case BPF_LDX | BPF_MEM | BPF_H: /* dst = *(u16 *)(ul) (src + off) */ |
| 954 | /* llgh %dst,0(off,%src) */ |
| 955 | EMIT6_DISP_LH(0xe3000000, 0x0091, dst_reg, src_reg, REG_0, off); |
| 956 | jit->seen |= SEEN_MEM; |
| 957 | break; |
| 958 | case BPF_LDX | BPF_MEM | BPF_W: /* dst = *(u32 *)(ul) (src + off) */ |
| 959 | /* llgf %dst,off(%src) */ |
| 960 | jit->seen |= SEEN_MEM; |
| 961 | EMIT6_DISP_LH(0xe3000000, 0x0016, dst_reg, src_reg, REG_0, off); |
| 962 | break; |
| 963 | case BPF_LDX | BPF_MEM | BPF_DW: /* dst = *(u64 *)(ul) (src + off) */ |
| 964 | /* lg %dst,0(off,%src) */ |
| 965 | jit->seen |= SEEN_MEM; |
| 966 | EMIT6_DISP_LH(0xe3000000, 0x0004, dst_reg, src_reg, REG_0, off); |
| 967 | break; |
| 968 | /* |
| 969 | * BPF_JMP / CALL |
| 970 | */ |
| 971 | case BPF_JMP | BPF_CALL: |
| 972 | { |
| 973 | /* |
| 974 | * b0 = (__bpf_call_base + imm)(b1, b2, b3, b4, b5) |
| 975 | */ |
| 976 | const u64 func = (u64)__bpf_call_base + imm; |
| 977 | |
| 978 | REG_SET_SEEN(BPF_REG_5); |
| 979 | jit->seen |= SEEN_FUNC; |
| 980 | /* lg %w1,<d(imm)>(%l) */ |
Michael Holzheu | ce2b6ad | 2015-07-29 21:15:16 +0200 | [diff] [blame] | 981 | EMIT6_DISP_LH(0xe3000000, 0x0004, REG_W1, REG_0, REG_L, |
| 982 | EMIT_CONST_U64(func)); |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 983 | /* basr %r14,%w1 */ |
| 984 | EMIT2(0x0d00, REG_14, REG_W1); |
| 985 | /* lgr %b0,%r2: load return value into %b0 */ |
| 986 | EMIT4(0xb9040000, BPF_REG_0, REG_2); |
Michael Holzheu | 9db7f2b | 2015-07-29 21:15:18 +0200 | [diff] [blame] | 987 | if (bpf_helper_changes_skb_data((void *)func)) { |
| 988 | jit->seen |= SEEN_SKB_CHANGE; |
| 989 | /* lg %b1,ST_OFF_SKBP(%r15) */ |
| 990 | EMIT6_DISP_LH(0xe3000000, 0x0004, BPF_REG_1, REG_0, |
| 991 | REG_15, STK_OFF_SKBP); |
| 992 | emit_load_skb_data_hlen(jit); |
| 993 | } |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 994 | break; |
| 995 | } |
Michael Holzheu | 6651ee0 | 2015-06-08 21:51:06 -0700 | [diff] [blame] | 996 | case BPF_JMP | BPF_CALL | BPF_X: |
| 997 | /* |
| 998 | * Implicit input: |
| 999 | * B1: pointer to ctx |
| 1000 | * B2: pointer to bpf_array |
| 1001 | * B3: index in bpf_array |
| 1002 | */ |
| 1003 | jit->seen |= SEEN_TAIL_CALL; |
| 1004 | |
| 1005 | /* |
| 1006 | * if (index >= array->map.max_entries) |
| 1007 | * goto out; |
| 1008 | */ |
| 1009 | |
| 1010 | /* llgf %w1,map.max_entries(%b2) */ |
| 1011 | EMIT6_DISP_LH(0xe3000000, 0x0016, REG_W1, REG_0, BPF_REG_2, |
| 1012 | offsetof(struct bpf_array, map.max_entries)); |
| 1013 | /* clgrj %b3,%w1,0xa,label0: if %b3 >= %w1 goto out */ |
| 1014 | EMIT6_PCREL_LABEL(0xec000000, 0x0065, BPF_REG_3, |
| 1015 | REG_W1, 0, 0xa); |
| 1016 | |
| 1017 | /* |
| 1018 | * if (tail_call_cnt++ > MAX_TAIL_CALL_CNT) |
| 1019 | * goto out; |
| 1020 | */ |
| 1021 | |
| 1022 | if (jit->seen & SEEN_STACK) |
| 1023 | off = STK_OFF_TCCNT + STK_OFF; |
| 1024 | else |
| 1025 | off = STK_OFF_TCCNT; |
| 1026 | /* lhi %w0,1 */ |
| 1027 | EMIT4_IMM(0xa7080000, REG_W0, 1); |
| 1028 | /* laal %w1,%w0,off(%r15) */ |
| 1029 | EMIT6_DISP_LH(0xeb000000, 0x00fa, REG_W1, REG_W0, REG_15, off); |
| 1030 | /* clij %w1,MAX_TAIL_CALL_CNT,0x2,label0 */ |
| 1031 | EMIT6_PCREL_IMM_LABEL(0xec000000, 0x007f, REG_W1, |
| 1032 | MAX_TAIL_CALL_CNT, 0, 0x2); |
| 1033 | |
| 1034 | /* |
Kaixu Xia | 2c9c3bb | 2015-08-11 08:56:51 +0000 | [diff] [blame] | 1035 | * prog = array->ptrs[index]; |
Michael Holzheu | 6651ee0 | 2015-06-08 21:51:06 -0700 | [diff] [blame] | 1036 | * if (prog == NULL) |
| 1037 | * goto out; |
| 1038 | */ |
| 1039 | |
| 1040 | /* sllg %r1,%b3,3: %r1 = index * 8 */ |
| 1041 | EMIT6_DISP_LH(0xeb000000, 0x000d, REG_1, BPF_REG_3, REG_0, 3); |
| 1042 | /* lg %r1,prog(%b2,%r1) */ |
| 1043 | EMIT6_DISP_LH(0xe3000000, 0x0004, REG_1, BPF_REG_2, |
Kaixu Xia | 2c9c3bb | 2015-08-11 08:56:51 +0000 | [diff] [blame] | 1044 | REG_1, offsetof(struct bpf_array, ptrs)); |
Michael Holzheu | 6651ee0 | 2015-06-08 21:51:06 -0700 | [diff] [blame] | 1045 | /* clgij %r1,0,0x8,label0 */ |
| 1046 | EMIT6_PCREL_IMM_LABEL(0xec000000, 0x007d, REG_1, 0, 0, 0x8); |
| 1047 | |
| 1048 | /* |
| 1049 | * Restore registers before calling function |
| 1050 | */ |
| 1051 | save_restore_regs(jit, REGS_RESTORE); |
| 1052 | |
| 1053 | /* |
| 1054 | * goto *(prog->bpf_func + tail_call_start); |
| 1055 | */ |
| 1056 | |
| 1057 | /* lg %r1,bpf_func(%r1) */ |
| 1058 | EMIT6_DISP_LH(0xe3000000, 0x0004, REG_1, REG_1, REG_0, |
| 1059 | offsetof(struct bpf_prog, bpf_func)); |
| 1060 | /* bc 0xf,tail_call_start(%r1) */ |
| 1061 | _EMIT4(0x47f01000 + jit->tail_call_start); |
| 1062 | /* out: */ |
| 1063 | jit->labels[0] = jit->prg; |
| 1064 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1065 | case BPF_JMP | BPF_EXIT: /* return b0 */ |
| 1066 | last = (i == fp->len - 1) ? 1 : 0; |
| 1067 | if (last && !(jit->seen & SEEN_RET0)) |
| 1068 | break; |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1069 | /* j <exit> */ |
| 1070 | EMIT4_PCREL(0xa7f40000, jit->exit_ip - jit->prg); |
| 1071 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1072 | /* |
| 1073 | * Branch relative (number of skipped instructions) to offset on |
| 1074 | * condition. |
| 1075 | * |
| 1076 | * Condition code to mask mapping: |
| 1077 | * |
| 1078 | * CC | Description | Mask |
| 1079 | * ------------------------------ |
| 1080 | * 0 | Operands equal | 8 |
| 1081 | * 1 | First operand low | 4 |
| 1082 | * 2 | First operand high | 2 |
| 1083 | * 3 | Unused | 1 |
| 1084 | * |
| 1085 | * For s390x relative branches: ip = ip + off_bytes |
| 1086 | * For BPF relative branches: insn = insn + off_insns + 1 |
| 1087 | * |
| 1088 | * For example for s390x with offset 0 we jump to the branch |
| 1089 | * instruction itself (loop) and for BPF with offset 0 we |
| 1090 | * branch to the instruction behind the branch. |
| 1091 | */ |
| 1092 | case BPF_JMP | BPF_JA: /* if (true) */ |
| 1093 | mask = 0xf000; /* j */ |
| 1094 | goto branch_oc; |
| 1095 | case BPF_JMP | BPF_JSGT | BPF_K: /* ((s64) dst > (s64) imm) */ |
| 1096 | mask = 0x2000; /* jh */ |
| 1097 | goto branch_ks; |
| 1098 | case BPF_JMP | BPF_JSGE | BPF_K: /* ((s64) dst >= (s64) imm) */ |
| 1099 | mask = 0xa000; /* jhe */ |
| 1100 | goto branch_ks; |
| 1101 | case BPF_JMP | BPF_JGT | BPF_K: /* (dst_reg > imm) */ |
| 1102 | mask = 0x2000; /* jh */ |
| 1103 | goto branch_ku; |
| 1104 | case BPF_JMP | BPF_JGE | BPF_K: /* (dst_reg >= imm) */ |
| 1105 | mask = 0xa000; /* jhe */ |
| 1106 | goto branch_ku; |
| 1107 | case BPF_JMP | BPF_JNE | BPF_K: /* (dst_reg != imm) */ |
| 1108 | mask = 0x7000; /* jne */ |
| 1109 | goto branch_ku; |
| 1110 | case BPF_JMP | BPF_JEQ | BPF_K: /* (dst_reg == imm) */ |
| 1111 | mask = 0x8000; /* je */ |
| 1112 | goto branch_ku; |
| 1113 | case BPF_JMP | BPF_JSET | BPF_K: /* (dst_reg & imm) */ |
| 1114 | mask = 0x7000; /* jnz */ |
| 1115 | /* lgfi %w1,imm (load sign extend imm) */ |
| 1116 | EMIT6_IMM(0xc0010000, REG_W1, imm); |
| 1117 | /* ngr %w1,%dst */ |
| 1118 | EMIT4(0xb9800000, REG_W1, dst_reg); |
| 1119 | goto branch_oc; |
| 1120 | |
| 1121 | case BPF_JMP | BPF_JSGT | BPF_X: /* ((s64) dst > (s64) src) */ |
| 1122 | mask = 0x2000; /* jh */ |
| 1123 | goto branch_xs; |
| 1124 | case BPF_JMP | BPF_JSGE | BPF_X: /* ((s64) dst >= (s64) src) */ |
| 1125 | mask = 0xa000; /* jhe */ |
| 1126 | goto branch_xs; |
| 1127 | case BPF_JMP | BPF_JGT | BPF_X: /* (dst > src) */ |
| 1128 | mask = 0x2000; /* jh */ |
| 1129 | goto branch_xu; |
| 1130 | case BPF_JMP | BPF_JGE | BPF_X: /* (dst >= src) */ |
| 1131 | mask = 0xa000; /* jhe */ |
| 1132 | goto branch_xu; |
| 1133 | case BPF_JMP | BPF_JNE | BPF_X: /* (dst != src) */ |
| 1134 | mask = 0x7000; /* jne */ |
| 1135 | goto branch_xu; |
| 1136 | case BPF_JMP | BPF_JEQ | BPF_X: /* (dst == src) */ |
| 1137 | mask = 0x8000; /* je */ |
| 1138 | goto branch_xu; |
| 1139 | case BPF_JMP | BPF_JSET | BPF_X: /* (dst & src) */ |
| 1140 | mask = 0x7000; /* jnz */ |
| 1141 | /* ngrk %w1,%dst,%src */ |
| 1142 | EMIT4_RRF(0xb9e40000, REG_W1, dst_reg, src_reg); |
| 1143 | goto branch_oc; |
| 1144 | branch_ks: |
| 1145 | /* lgfi %w1,imm (load sign extend imm) */ |
| 1146 | EMIT6_IMM(0xc0010000, REG_W1, imm); |
| 1147 | /* cgrj %dst,%w1,mask,off */ |
| 1148 | EMIT6_PCREL(0xec000000, 0x0064, dst_reg, REG_W1, i, off, mask); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1149 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1150 | branch_ku: |
| 1151 | /* lgfi %w1,imm (load sign extend imm) */ |
| 1152 | EMIT6_IMM(0xc0010000, REG_W1, imm); |
| 1153 | /* clgrj %dst,%w1,mask,off */ |
| 1154 | EMIT6_PCREL(0xec000000, 0x0065, dst_reg, REG_W1, i, off, mask); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1155 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1156 | branch_xs: |
| 1157 | /* cgrj %dst,%src,mask,off */ |
| 1158 | EMIT6_PCREL(0xec000000, 0x0064, dst_reg, src_reg, i, off, mask); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1159 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1160 | branch_xu: |
| 1161 | /* clgrj %dst,%src,mask,off */ |
| 1162 | EMIT6_PCREL(0xec000000, 0x0065, dst_reg, src_reg, i, off, mask); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1163 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1164 | branch_oc: |
| 1165 | /* brc mask,jmp_off (branch instruction needs 4 bytes) */ |
| 1166 | jmp_off = addrs[i + off + 1] - (addrs[i + 1] - 4); |
| 1167 | EMIT4_PCREL(0xa7040000 | mask << 8, jmp_off); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1168 | break; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1169 | /* |
| 1170 | * BPF_LD |
| 1171 | */ |
| 1172 | case BPF_LD | BPF_ABS | BPF_B: /* b0 = *(u8 *) (skb->data+imm) */ |
| 1173 | case BPF_LD | BPF_IND | BPF_B: /* b0 = *(u8 *) (skb->data+imm+src) */ |
| 1174 | if ((BPF_MODE(insn->code) == BPF_ABS) && (imm >= 0)) |
| 1175 | func_addr = __pa(sk_load_byte_pos); |
| 1176 | else |
| 1177 | func_addr = __pa(sk_load_byte); |
| 1178 | goto call_fn; |
| 1179 | case BPF_LD | BPF_ABS | BPF_H: /* b0 = *(u16 *) (skb->data+imm) */ |
| 1180 | case BPF_LD | BPF_IND | BPF_H: /* b0 = *(u16 *) (skb->data+imm+src) */ |
| 1181 | if ((BPF_MODE(insn->code) == BPF_ABS) && (imm >= 0)) |
| 1182 | func_addr = __pa(sk_load_half_pos); |
| 1183 | else |
| 1184 | func_addr = __pa(sk_load_half); |
| 1185 | goto call_fn; |
| 1186 | case BPF_LD | BPF_ABS | BPF_W: /* b0 = *(u32 *) (skb->data+imm) */ |
| 1187 | case BPF_LD | BPF_IND | BPF_W: /* b0 = *(u32 *) (skb->data+imm+src) */ |
| 1188 | if ((BPF_MODE(insn->code) == BPF_ABS) && (imm >= 0)) |
| 1189 | func_addr = __pa(sk_load_word_pos); |
| 1190 | else |
| 1191 | func_addr = __pa(sk_load_word); |
| 1192 | goto call_fn; |
| 1193 | call_fn: |
| 1194 | jit->seen |= SEEN_SKB | SEEN_RET0 | SEEN_FUNC; |
| 1195 | REG_SET_SEEN(REG_14); /* Return address of possible func call */ |
| 1196 | |
| 1197 | /* |
| 1198 | * Implicit input: |
| 1199 | * BPF_REG_6 (R7) : skb pointer |
| 1200 | * REG_SKB_DATA (R12): skb data pointer |
| 1201 | * |
| 1202 | * Calculated input: |
| 1203 | * BPF_REG_2 (R3) : offset of byte(s) to fetch in skb |
| 1204 | * BPF_REG_5 (R6) : return address |
| 1205 | * |
| 1206 | * Output: |
| 1207 | * BPF_REG_0 (R14): data read from skb |
| 1208 | * |
| 1209 | * Scratch registers (BPF_REG_1-5) |
| 1210 | */ |
| 1211 | |
| 1212 | /* Call function: llilf %w1,func_addr */ |
| 1213 | EMIT6_IMM(0xc00f0000, REG_W1, func_addr); |
| 1214 | |
| 1215 | /* Offset: lgfi %b2,imm */ |
| 1216 | EMIT6_IMM(0xc0010000, BPF_REG_2, imm); |
| 1217 | if (BPF_MODE(insn->code) == BPF_IND) |
| 1218 | /* agfr %b2,%src (%src is s32 here) */ |
| 1219 | EMIT4(0xb9180000, BPF_REG_2, src_reg); |
| 1220 | |
| 1221 | /* basr %b5,%w1 (%b5 is call saved) */ |
| 1222 | EMIT2(0x0d00, BPF_REG_5, REG_W1); |
| 1223 | |
| 1224 | /* |
| 1225 | * Note: For fast access we jump directly after the |
| 1226 | * jnz instruction from bpf_jit.S |
| 1227 | */ |
| 1228 | /* jnz <ret0> */ |
| 1229 | EMIT4_PCREL(0xa7740000, jit->ret0_ip - jit->prg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1230 | break; |
| 1231 | default: /* too complex, give up */ |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1232 | pr_err("Unknown opcode %02x\n", insn->code); |
| 1233 | return -1; |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1234 | } |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1235 | return insn_count; |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1236 | } |
| 1237 | |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1238 | /* |
| 1239 | * Compile eBPF program into s390x code |
| 1240 | */ |
| 1241 | static int bpf_jit_prog(struct bpf_jit *jit, struct bpf_prog *fp) |
| 1242 | { |
| 1243 | int i, insn_count; |
| 1244 | |
| 1245 | jit->lit = jit->lit_start; |
| 1246 | jit->prg = 0; |
| 1247 | |
Daniel Borkmann | 7b36f92 | 2015-07-30 12:42:47 +0200 | [diff] [blame] | 1248 | bpf_jit_prologue(jit, bpf_prog_was_classic(fp)); |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1249 | for (i = 0; i < fp->len; i += insn_count) { |
| 1250 | insn_count = bpf_jit_insn(jit, fp, i); |
| 1251 | if (insn_count < 0) |
| 1252 | return -1; |
| 1253 | jit->addrs[i + 1] = jit->prg; /* Next instruction address */ |
| 1254 | } |
| 1255 | bpf_jit_epilogue(jit); |
| 1256 | |
| 1257 | jit->lit_start = jit->prg; |
| 1258 | jit->size = jit->lit; |
| 1259 | jit->size_prg = jit->prg; |
| 1260 | return 0; |
| 1261 | } |
| 1262 | |
| 1263 | /* |
| 1264 | * Classic BPF function stub. BPF programs will be converted into |
| 1265 | * eBPF and then bpf_int_jit_compile() will be called. |
| 1266 | */ |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 1267 | void bpf_jit_compile(struct bpf_prog *fp) |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1268 | { |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1269 | } |
| 1270 | |
| 1271 | /* |
| 1272 | * Compile eBPF program "fp" |
| 1273 | */ |
| 1274 | void bpf_int_jit_compile(struct bpf_prog *fp) |
| 1275 | { |
| 1276 | struct bpf_binary_header *header; |
| 1277 | struct bpf_jit jit; |
| 1278 | int pass; |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1279 | |
| 1280 | if (!bpf_jit_enable) |
| 1281 | return; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1282 | memset(&jit, 0, sizeof(jit)); |
| 1283 | jit.addrs = kcalloc(fp->len + 1, sizeof(*jit.addrs), GFP_KERNEL); |
| 1284 | if (jit.addrs == NULL) |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1285 | return; |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1286 | /* |
| 1287 | * Three initial passes: |
| 1288 | * - 1/2: Determine clobbered registers |
| 1289 | * - 3: Calculate program size and addrs arrray |
| 1290 | */ |
| 1291 | for (pass = 1; pass <= 3; pass++) { |
| 1292 | if (bpf_jit_prog(&jit, fp)) |
| 1293 | goto free_addrs; |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1294 | } |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1295 | /* |
| 1296 | * Final pass: Allocate and generate program |
| 1297 | */ |
| 1298 | if (jit.size >= BPF_SIZE_MAX) |
| 1299 | goto free_addrs; |
| 1300 | header = bpf_jit_binary_alloc(jit.size, &jit.prg_buf, 2, jit_fill_hole); |
| 1301 | if (!header) |
| 1302 | goto free_addrs; |
| 1303 | if (bpf_jit_prog(&jit, fp)) |
| 1304 | goto free_addrs; |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1305 | if (bpf_jit_enable > 1) { |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1306 | bpf_jit_dump(fp->len, jit.size, pass, jit.prg_buf); |
| 1307 | if (jit.prg_buf) |
| 1308 | print_fn_code(jit.prg_buf, jit.size_prg); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1309 | } |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1310 | if (jit.prg_buf) { |
Heiko Carstens | aa2d2c7 | 2013-07-16 13:25:49 +0200 | [diff] [blame] | 1311 | set_memory_ro((unsigned long)header, header->pages); |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1312 | fp->bpf_func = (void *) jit.prg_buf; |
Daniel Borkmann | a91263d | 2015-09-30 01:41:50 +0200 | [diff] [blame] | 1313 | fp->jited = 1; |
Heiko Carstens | aa2d2c7 | 2013-07-16 13:25:49 +0200 | [diff] [blame] | 1314 | } |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1315 | free_addrs: |
| 1316 | kfree(jit.addrs); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1317 | } |
| 1318 | |
Michael Holzheu | 0546231 | 2015-04-01 16:08:32 +0200 | [diff] [blame] | 1319 | /* |
| 1320 | * Free eBPF program |
| 1321 | */ |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 1322 | void bpf_jit_free(struct bpf_prog *fp) |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1323 | { |
Heiko Carstens | aa2d2c7 | 2013-07-16 13:25:49 +0200 | [diff] [blame] | 1324 | unsigned long addr = (unsigned long)fp->bpf_func & PAGE_MASK; |
| 1325 | struct bpf_binary_header *header = (void *)addr; |
| 1326 | |
Daniel Borkmann | f8bbbfc | 2014-03-28 18:58:18 +0100 | [diff] [blame] | 1327 | if (!fp->jited) |
Alexei Starovoitov | d45ed4a | 2013-10-04 00:14:06 -0700 | [diff] [blame] | 1328 | goto free_filter; |
Daniel Borkmann | f8bbbfc | 2014-03-28 18:58:18 +0100 | [diff] [blame] | 1329 | |
Heiko Carstens | aa2d2c7 | 2013-07-16 13:25:49 +0200 | [diff] [blame] | 1330 | set_memory_rw(addr, header->pages); |
Daniel Borkmann | 738cbe7 | 2014-09-08 08:04:47 +0200 | [diff] [blame] | 1331 | bpf_jit_binary_free(header); |
Daniel Borkmann | f8bbbfc | 2014-03-28 18:58:18 +0100 | [diff] [blame] | 1332 | |
Alexei Starovoitov | d45ed4a | 2013-10-04 00:14:06 -0700 | [diff] [blame] | 1333 | free_filter: |
Daniel Borkmann | 60a3b22 | 2014-09-02 22:53:44 +0200 | [diff] [blame] | 1334 | bpf_prog_unlock_free(fp); |
Martin Schwidefsky | c10302e | 2012-07-31 16:23:59 +0200 | [diff] [blame] | 1335 | } |