copyout.c revision 1.6
1 /* $NetBSD: copyout.c,v 1.6 2020/03/04 13:01:52 rin Exp $ */ 2 3 /*- 4 * Copyright (c) 2010, 2011 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Raytheon BBN Technologies Corp and Defense Advanced Research Projects 9 * Agency and which was developed by Matt Thomas of 3am Software Foundry. 10 * 11 * This material is based upon work supported by the Defense Advanced Research 12 * Projects Agency and Space and Naval Warfare Systems Center, Pacific, under 13 * Contract No. N66001-09-C-2073. 14 * Approved for Public Release, Distribution Unlimited 15 * 16 * Redistribution and use in source and binary forms, with or without 17 * modification, are permitted provided that the following conditions 18 * are met: 19 * 1. Redistributions of source code must retain the above copyright 20 * notice, this list of conditions and the following disclaimer. 21 * 2. Redistributions in binary form must reproduce the above copyright 22 * notice, this list of conditions and the following disclaimer in the 23 * documentation and/or other materials provided with the distribution. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 26 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 * POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38 #include <sys/cdefs.h> 39 __KERNEL_RCSID(0, "$NetBSD: copyout.c,v 1.6 2020/03/04 13:01:52 rin Exp $"); 40 41 #define __UFETCHSTORE_PRIVATE 42 43 #include <sys/param.h> 44 #include <sys/lwp.h> 45 #include <sys/systm.h> 46 47 #include <powerpc/pcb.h> 48 49 #include <powerpc/booke/cpuvar.h> 50 51 static inline void 52 copyout_uint8(uint8_t *udaddr, uint8_t data, register_t ds_msr) 53 { 54 register_t msr; 55 __asm volatile( 56 "mfmsr %[msr]" /* Save MSR */ 57 "\n\t" "mtmsr %[ds_msr]; sync; isync" /* DS on */ 58 "\n\t" "stb %[data],0(%[udaddr])" /* store user byte */ 59 "\n\t" "mtmsr %[msr]; sync; isync" /* DS off */ 60 : [msr] "=&r" (msr) 61 : [ds_msr] "r" (ds_msr), [data] "r" (data), [udaddr] "b" (udaddr)); 62 } 63 64 static inline void 65 copyout_uint16(uint16_t *udaddr, uint8_t data, register_t ds_msr) 66 { 67 register_t msr; 68 __asm volatile( 69 "mfmsr %[msr]" /* Save MSR */ 70 "\n\t" "mtmsr %[ds_msr]; sync; isync" /* DS on */ 71 "\n\t" "sth %[data],0(%[udaddr])" /* store user half */ 72 "\n\t" "mtmsr %[msr]; sync; isync" /* DS off */ 73 : [msr] "=&r" (msr) 74 : [ds_msr] "r" (ds_msr), [data] "r" (data), [udaddr] "b" (udaddr)); 75 } 76 77 static inline void 78 copyout_uint32(uint32_t * const udaddr, uint32_t data, register_t ds_msr) 79 { 80 register_t msr; 81 __asm volatile( 82 "mfmsr %[msr]" /* Save MSR */ 83 "\n\t" "mtmsr %[ds_msr]; sync; isync" /* DS on */ 84 "\n\t" "stw %[data],0(%[udaddr])" /* store user data */ 85 "\n\t" "mtmsr %[msr]; sync; isync" /* DS off */ 86 : [msr] "=&r" (msr) 87 : [ds_msr] "r" (ds_msr), [data] "r" (data), [udaddr] "b" (udaddr)); 88 } 89 90 #if 0 91 static inline void 92 copyout_le32(uint32_t * const udaddr, uint32_t data, register_t ds_msr) 93 { 94 register_t msr; 95 __asm volatile( 96 "mfmsr %[msr]" /* Save MSR */ 97 "\n\t" "mtmsr %[ds_msr]; sync; isync" /* DS on */ 98 "\n\t" "stwbrx %[data],0,%[udaddr]" /* store user data */ 99 "\n\t" "mtmsr %[msr]; sync; isync" /* DS off */ 100 : [msr] "=&r" (msr) 101 : [ds_msr] "r" (ds_msr), [data] "r" (data), [udaddr] "b" (udaddr)); 102 } 103 104 static inline void 105 copyout_le32_with_mask(uint32_t * const udaddr, uint32_t data, 106 uint32_t mask, register_t ds_msr) 107 { 108 register_t msr; 109 uint32_t tmp; 110 KASSERT((data & ~mask) == 0); 111 __asm volatile( 112 "mfmsr %[msr]" /* Save MSR */ 113 "\n\t" "mtmsr %[ds_msr]; sync; isync" /* DS on */ 114 "\n\t" "lwbrx %[tmp],0,%[udaddr]" /* fetch user data */ 115 "\n\t" "andc %[tmp],%[tmp],%[mask]" /* mask out new data */ 116 "\n\t" "or %[tmp],%[tmp],%[data]" /* merge new data */ 117 "\n\t" "stwbrx %[tmp],0,%[udaddr]" /* store user data */ 118 "\n\t" "mtmsr %[msr]; sync; isync" /* DS off */ 119 : [msr] "=&r" (msr), [tmp] "=&r" (tmp) 120 : [ds_msr] "r" (ds_msr), [data] "r" (data), 121 [mask] "r" (mask), [udaddr] "b" (udaddr)); 122 } 123 #endif 124 125 static inline void 126 copyout_16uint8s(const uint8_t *ksaddr8, uint8_t *udaddr8, register_t ds_msr) 127 { 128 register_t msr; 129 __asm volatile( 130 "mfmsr %[msr]" /* Save MSR */ 131 "\n\t" "mtmsr %[ds_msr]; sync; isync" /* DS on */ 132 "\n\t" "stb %[data0],0(%[udaddr8])" /* store user data */ 133 "\n\t" "stb %[data1],1(%[udaddr8])" /* store user data */ 134 "\n\t" "stb %[data2],2(%[udaddr8])" /* store user data */ 135 "\n\t" "stb %[data3],3(%[udaddr8])" /* store user data */ 136 "\n\t" "stb %[data4],4(%[udaddr8])" /* store user data */ 137 "\n\t" "stb %[data5],5(%[udaddr8])" /* store user data */ 138 "\n\t" "stb %[data6],6(%[udaddr8])" /* store user data */ 139 "\n\t" "stb %[data7],7(%[udaddr8])" /* store user data */ 140 "\n\t" "stb %[data8],8(%[udaddr8])" /* store user data */ 141 "\n\t" "stb %[data9],9(%[udaddr8])" /* store user data */ 142 "\n\t" "stb %[data10],10(%[udaddr8])" /* store user data */ 143 "\n\t" "stb %[data11],11(%[udaddr8])" /* store user data */ 144 "\n\t" "stb %[data12],12(%[udaddr8])" /* store user data */ 145 "\n\t" "stb %[data13],13(%[udaddr8])" /* store user data */ 146 "\n\t" "stb %[data14],14(%[udaddr8])" /* store user data */ 147 "\n\t" "stb %[data15],15(%[udaddr8])" /* store user data */ 148 "\n\t" "mtmsr %[msr]; sync; isync" /* DS off */ 149 : [msr] "=&r" (msr) 150 : [ds_msr] "r" (ds_msr), [udaddr8] "b" (udaddr8), 151 [data0] "r" (ksaddr8[0]), [data1] "r" (ksaddr8[1]), 152 [data2] "r" (ksaddr8[2]), [data3] "r" (ksaddr8[3]), 153 [data4] "r" (ksaddr8[4]), [data5] "r" (ksaddr8[5]), 154 [data6] "r" (ksaddr8[6]), [data7] "r" (ksaddr8[7]), 155 [data8] "r" (ksaddr8[8]), [data9] "r" (ksaddr8[9]), 156 [data10] "r" (ksaddr8[10]), [data11] "r" (ksaddr8[11]), 157 [data12] "r" (ksaddr8[12]), [data13] "r" (ksaddr8[13]), 158 [data14] "r" (ksaddr8[14]), [data15] "r" (ksaddr8[15])); 159 } 160 161 static inline void 162 copyout_8uint32s(const uint32_t * const ksaddr32, uint32_t * const udaddr32, 163 const register_t ds_msr, const size_t line_mask) 164 { 165 register_t msr; 166 register_t tmp; 167 __asm volatile( 168 "and. %[tmp],%[line_mask],%[udaddr32]" 169 "\n\t" "mfmsr %[msr]" /* Save MSR */ 170 "\n\t" "mtmsr %[ds_msr]; sync; isync" /* DS on */ 171 "\n\t" "bne 0,1f" 172 "\n\t" "dcba 0,%[udaddr32]" 173 "\n" "1:" 174 "\n\t" "stw %[data0],0(%[udaddr32])" /* store user data */ 175 "\n\t" "stw %[data1],4(%[udaddr32])" /* store user data */ 176 "\n\t" "stw %[data2],8(%[udaddr32])" /* store user data */ 177 "\n\t" "stw %[data3],12(%[udaddr32])" /* store user data */ 178 "\n\t" "stw %[data4],16(%[udaddr32])" /* store user data */ 179 "\n\t" "stw %[data5],20(%[udaddr32])" /* store user data */ 180 "\n\t" "stw %[data6],24(%[udaddr32])" /* store user data */ 181 "\n\t" "stw %[data7],28(%[udaddr32])" /* store user data */ 182 "\n\t" "mtmsr %[msr]; sync; isync" /* DS off */ 183 : [msr] "=&r" (msr), [tmp] "=&r" (tmp) 184 : [ds_msr] "r" (ds_msr), [udaddr32] "b" (udaddr32), 185 [line_mask] "r" (line_mask), 186 [data0] "r" (ksaddr32[0]), [data1] "r" (ksaddr32[1]), 187 [data2] "r" (ksaddr32[2]), [data3] "r" (ksaddr32[3]), 188 [data4] "r" (ksaddr32[4]), [data5] "r" (ksaddr32[5]), 189 [data6] "r" (ksaddr32[6]), [data7] "r" (ksaddr32[7]) 190 : "cr0"); 191 } 192 193 static inline void 194 copyout_16uint32s(const uint32_t * const ksaddr32, uint32_t * const udaddr32, 195 const register_t ds_msr, const size_t line_mask) 196 { 197 KASSERT(((uintptr_t)udaddr32 & line_mask) == 0); 198 register_t msr; 199 register_t tmp; 200 __asm volatile( 201 "and. %[tmp],%[line_mask],%[udaddr32]" 202 "\n\t" "cmplwi 2,%[line_size],32" 203 "\n\t" "mfmsr %[msr]" /* Save MSR */ 204 "\n\t" "mtmsr %[ds_msr]; sync; isync" /* DS on */ 205 "\n\t" "bne 0,1f" 206 "\n\t" "dcba 0,%[udaddr32]" 207 "\n\t" "bne 2,1f" 208 "\n\t" "dcba %[line_size],%[udaddr32]" 209 "\n" "1:" 210 "\n\t" "stw %[data0],0(%[udaddr32])" /* store user data */ 211 "\n\t" "stw %[data1],4(%[udaddr32])" /* store user data */ 212 "\n\t" "stw %[data2],8(%[udaddr32])" /* store user data */ 213 "\n\t" "stw %[data3],12(%[udaddr32])" /* store user data */ 214 "\n\t" "stw %[data4],16(%[udaddr32])" /* store user data */ 215 "\n\t" "stw %[data5],20(%[udaddr32])" /* store user data */ 216 "\n\t" "stw %[data6],24(%[udaddr32])" /* store user data */ 217 "\n\t" "stw %[data7],28(%[udaddr32])" /* store user data */ 218 "\n\t" "stw %[data8],32(%[udaddr32])" /* store user data */ 219 "\n\t" "stw %[data9],36(%[udaddr32])" /* store user data */ 220 "\n\t" "stw %[data10],40(%[udaddr32])" /* store user data */ 221 "\n\t" "stw %[data11],44(%[udaddr32])" /* store user data */ 222 "\n\t" "stw %[data12],48(%[udaddr32])" /* store user data */ 223 "\n\t" "stw %[data13],52(%[udaddr32])" /* store user data */ 224 "\n\t" "stw %[data14],56(%[udaddr32])" /* store user data */ 225 "\n\t" "stw %[data15],60(%[udaddr32])" /* store user data */ 226 "\n\t" "mtmsr %[msr]; sync; isync" /* DS off */ 227 : [msr] "=&r" (msr), [tmp] "=&r" (tmp) 228 : [ds_msr] "r" (ds_msr), [udaddr32] "b" (udaddr32), 229 [line_size] "r" (line_mask + 1), [line_mask] "r" (line_mask), 230 [data0] "r" (ksaddr32[0]), [data1] "r" (ksaddr32[1]), 231 [data2] "r" (ksaddr32[2]), [data3] "r" (ksaddr32[3]), 232 [data4] "r" (ksaddr32[4]), [data5] "r" (ksaddr32[5]), 233 [data6] "r" (ksaddr32[6]), [data7] "r" (ksaddr32[7]), 234 [data8] "r" (ksaddr32[8]), [data9] "r" (ksaddr32[9]), 235 [data10] "r" (ksaddr32[10]), [data11] "r" (ksaddr32[11]), 236 [data12] "r" (ksaddr32[12]), [data13] "r" (ksaddr32[13]), 237 [data14] "r" (ksaddr32[14]), [data15] "r" (ksaddr32[15]) 238 : "cr0", "cr2"); 239 } 240 241 static inline void 242 copyout_uint8s(vaddr_t ksaddr, vaddr_t udaddr, size_t len, register_t ds_msr) 243 { 244 const uint8_t *ksaddr8 = (void *)ksaddr; 245 uint8_t *udaddr8 = (void *)udaddr; 246 247 __builtin_prefetch(ksaddr8, 0, 1); 248 249 for (; len >= 16; len -= 16, ksaddr8 += 16, udaddr8 += 16) { 250 __builtin_prefetch(ksaddr8 + 16, 0, 1); 251 copyout_16uint8s(ksaddr8, udaddr8, ds_msr); 252 } 253 254 while (len-- > 0) { 255 copyout_uint8(udaddr8++, *ksaddr8++, ds_msr); 256 } 257 } 258 259 static inline void 260 copyout_uint32s(vaddr_t ksaddr, vaddr_t udaddr, size_t len, register_t ds_msr) 261 { 262 const size_t line_size = curcpu()->ci_ci.dcache_line_size; 263 const size_t line_mask = line_size - 1; 264 const size_t udalignment = udaddr & line_mask; 265 KASSERT((ksaddr & 3) == 0); 266 KASSERT((udaddr & 3) == 0); 267 const uint32_t *ksaddr32 = (void *)ksaddr; 268 uint32_t *udaddr32 = (void *)udaddr; 269 len >>= 2; 270 __builtin_prefetch(ksaddr32, 0, 1); 271 if (udalignment != 0 && udalignment + 4*len > line_size) { 272 size_t slen = (line_size - udalignment) >> 2; 273 len -= slen; 274 for (; slen >= 8; ksaddr32 += 8, udaddr32 += 8, slen -= 8) { 275 copyout_8uint32s(ksaddr32, udaddr32, ds_msr, line_mask); 276 } 277 while (slen-- > 0) { 278 copyout_uint32(udaddr32++, *ksaddr32++, ds_msr); 279 } 280 if (len == 0) 281 return; 282 } 283 __builtin_prefetch(ksaddr32, 0, 1); 284 while (len >= 16) { 285 __builtin_prefetch(ksaddr32 + 8, 0, 1); 286 __builtin_prefetch(ksaddr32 + 16, 0, 1); 287 copyout_16uint32s(ksaddr32, udaddr32, ds_msr, line_mask); 288 ksaddr32 += 16, udaddr32 += 16, len -= 16; 289 } 290 KASSERT(len <= 16); 291 if (len >= 8) { 292 __builtin_prefetch(ksaddr32 + 8, 0, 1); 293 copyout_8uint32s(ksaddr32, udaddr32, ds_msr, line_mask); 294 ksaddr32 += 8, udaddr32 += 8, len -= 8; 295 } 296 while (len-- > 0) { 297 copyout_uint32(udaddr32++, *ksaddr32++, ds_msr); 298 } 299 } 300 301 int 302 _ustore_8(uint8_t *vusaddr, uint8_t val) 303 { 304 struct pcb * const pcb = lwp_getpcb(curlwp); 305 struct faultbuf env; 306 307 if (setfault(&env) != 0) { 308 pcb->pcb_onfault = NULL; 309 return EFAULT; 310 } 311 312 copyout_uint8(vusaddr, val, mfmsr() | PSL_DS); 313 314 pcb->pcb_onfault = NULL; 315 316 return 0; 317 } 318 319 int 320 _ustore_16(uint16_t *vusaddr, uint16_t val) 321 { 322 struct pcb * const pcb = lwp_getpcb(curlwp); 323 struct faultbuf env; 324 325 if (setfault(&env) != 0) { 326 pcb->pcb_onfault = NULL; 327 return EFAULT; 328 } 329 330 copyout_uint16(vusaddr, val, mfmsr() | PSL_DS); 331 332 pcb->pcb_onfault = NULL; 333 334 return 0; 335 } 336 337 int 338 _ustore_32(uint32_t *vusaddr, uint32_t val) 339 { 340 struct pcb * const pcb = lwp_getpcb(curlwp); 341 struct faultbuf env; 342 343 if (setfault(&env) != 0) { 344 pcb->pcb_onfault = NULL; 345 return EFAULT; 346 } 347 348 copyout_uint32(vusaddr, val, mfmsr() | PSL_DS); 349 350 pcb->pcb_onfault = NULL; 351 352 return 0; 353 } 354 355 int 356 copyout(const void *vksaddr, void *vudaddr, size_t len) 357 { 358 struct pcb * const pcb = lwp_getpcb(curlwp); 359 struct faultbuf env; 360 vaddr_t udaddr = (vaddr_t) vudaddr; 361 vaddr_t ksaddr = (vaddr_t) vksaddr; 362 363 if (__predict_false(len == 0)) { 364 return 0; 365 } 366 367 const register_t ds_msr = mfmsr() | PSL_DS; 368 369 int rv = setfault(&env); 370 if (rv != 0) { 371 pcb->pcb_onfault = NULL; 372 return rv; 373 } 374 375 if (__predict_false(len < 4)) { 376 copyout_uint8s(ksaddr, udaddr, len, ds_msr); 377 pcb->pcb_onfault = NULL; 378 return 0; 379 } 380 381 const size_t alignment = (udaddr ^ ksaddr) & 3; 382 if (__predict_true(alignment == 0)) { 383 size_t slen; 384 if (__predict_false(ksaddr & 3)) { 385 slen = 4 - (ksaddr & 3); 386 copyout_uint8s(ksaddr, udaddr, slen, ds_msr); 387 udaddr += slen, ksaddr += slen, len -= slen; 388 } 389 slen = len & ~3; 390 if (__predict_true(slen >= 4)) { 391 copyout_uint32s(ksaddr, udaddr, slen, ds_msr); 392 udaddr += slen, ksaddr += slen, len -= slen; 393 } 394 } 395 396 if (len > 0) { 397 copyout_uint8s(ksaddr, udaddr, len, ds_msr); 398 } 399 pcb->pcb_onfault = NULL; 400 return 0; 401 } 402 403 #if 1 404 int 405 copyoutstr(const void *ksaddr, void *udaddr, size_t len, size_t *lenp) 406 { 407 struct pcb * const pcb = lwp_getpcb(curlwp); 408 struct faultbuf env; 409 410 if (__predict_false(len == 0)) { 411 if (lenp) 412 *lenp = 0; 413 return 0; 414 } 415 416 if (setfault(&env)) { 417 pcb->pcb_onfault = NULL; 418 if (lenp) 419 *lenp = 0; 420 return EFAULT; 421 } 422 423 const register_t ds_msr = mfmsr() | PSL_DS; 424 const uint8_t *ksaddr8 = ksaddr; 425 size_t copylen = 0; 426 427 uint8_t *udaddr8 = (void *)udaddr; 428 429 while (copylen++ < len) { 430 const uint8_t data = *ksaddr8++; 431 copyout_uint8(udaddr8++, data, ds_msr); 432 if (data == 0) 433 break; 434 } 435 436 pcb->pcb_onfault = NULL; 437 if (lenp) 438 *lenp = copylen; 439 return 0; 440 } 441 #else 442 /* XXX This version of copyoutstr(9) has never beeen enabled so far. */ 443 int 444 copyoutstr(const void *ksaddr, void *udaddr, size_t len, size_t *lenp) 445 { 446 struct pcb * const pcb = lwp_getpcb(curlwp); 447 struct faultbuf env; 448 449 if (__predict_false(len == 0)) { 450 if (lenp) 451 *lenp = 0; 452 return 0; 453 } 454 455 if (setfault(&env)) { 456 pcb->pcb_onfault = NULL; 457 if (lenp) 458 *lenp = 0; 459 return EFAULT; 460 } 461 462 const register_t ds_msr = mfmsr() | PSL_DS; 463 const uint8_t *ksaddr8 = ksaddr; 464 size_t copylen = 0; 465 466 uint32_t *udaddr32 = (void *)((uintptr_t)udaddr & ~3); 467 468 size_t boff = (uintptr_t)udaddr & 3; 469 bool done = false; 470 size_t wlen = 0; 471 size_t data = 0; 472 473 /* 474 * If the destination buffer doesn't start on a 32-bit boundary 475 * try to partially fill in the first word. If we succeed we can 476 * finish writing it while preserving the bytes on front. 477 */ 478 if (boff > 0) { 479 KASSERT(len > 0); 480 do { 481 data = (data << 8) | *ksaddr8++; 482 wlen++; 483 done = ((uint8_t)data == 0 || len == wlen); 484 } while (!done && boff + wlen < 4); 485 KASSERT(wlen > 0); 486 data <<= 8 * boff; 487 if (!done || boff + wlen == 4) { 488 uint32_t mask = 0xffffffff << (8 * boff); 489 copyout_le32_with_mask(udaddr32++, data, mask, ds_msr); 490 boff = 0; 491 copylen = wlen; 492 wlen = 0; 493 data = 0; 494 } 495 } 496 497 /* 498 * Now we get to the heart of the routine. Build up complete words 499 * if possible. When we have one, write it to the user's address 500 * space and go for the next. If we ran out of space or we found the 501 * end of the string, stop building. If we managed to build a complete 502 * word, just write it and be happy. Otherwise we have to deal with 503 * the trailing bytes. 504 */ 505 KASSERT(done || boff == 0); 506 KASSERT(done || copylen < len); 507 while (!done) { 508 KASSERT(wlen == 0); 509 KASSERT(copylen < len); 510 do { 511 data = (data << 8) | *ksaddr8++; 512 wlen++; 513 done = ((uint8_t)data == 0 || copylen + wlen == len); 514 } while (!done && wlen < 4); 515 KASSERT(done || wlen == 4); 516 if (__predict_true(wlen == 4)) { 517 copyout_le32(udaddr32++, data, ds_msr); 518 data = 0; 519 copylen += wlen; 520 wlen = 0; 521 KASSERT(copylen < len || done); 522 } 523 } 524 KASSERT(wlen < 3); 525 if (wlen) { 526 /* 527 * Remember even though we are running big-endian we are using 528 * byte reversed load/stores so we need to deal with things as 529 * little endian. 530 * 531 * wlen=1 boff=0: 532 * (~(~0 << 8) << 0) -> (~(0xffffff00) << 0) -> 0x000000ff 533 * wlen=1 boff=1: 534 * (~(~0 << 8) << 8) -> (~(0xffffff00) << 8) -> 0x0000ff00 535 * wlen=1 boff=2: 536 * (~(~0 << 8) << 16) -> (~(0xffffff00) << 16) -> 0x00ff0000 537 * wlen=1 boff=3: 538 * (~(~0 << 8) << 24) -> (~(0xffffff00) << 24) -> 0xff000000 539 * wlen=2 boff=0: 540 * (~(~0 << 16) << 0) -> (~(0xffff0000) << 0) -> 0x0000ffff 541 * wlen=2 boff=1: 542 * (~(~0 << 16) << 8) -> (~(0xffff0000) << 8) -> 0x00ffff00 543 * wlen=2 boff=2: 544 * (~(~0 << 16) << 16) -> (~(0xffff0000) << 16) -> 0xffff0000 545 * wlen=3 boff=0: 546 * (~(~0 << 24) << 0) -> (~(0xff000000) << 0) -> 0x00ffffff 547 * wlen=3 boff=1: 548 * (~(~0 << 24) << 8) -> (~(0xff000000) << 8) -> 0xffffff00 549 */ 550 KASSERT(boff + wlen <= 4); 551 uint32_t mask = (~(~0 << (8 * wlen))) << (8 * boff); 552 KASSERT(mask != 0xffffffff); 553 copyout_le32_with_mask(udaddr32, data, mask, ds_msr); 554 copylen += wlen; 555 } 556 557 pcb->pcb_onfault = NULL; 558 if (lenp) 559 *lenp = copylen; 560 return 0; 561 } 562 #endif 563
Indexes created Tue Sep 30 20:09:53 GMT 2025