1 /* 2 * Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC. 3 * Copyright (C) 2007 The Regents of the University of California. 4 * Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER). 5 * Written by Brian Behlendorf <behlendorf1@llnl.gov>. 6 * UCRL-CODE-235197 7 * 8 * This file is part of the SPL, Solaris Porting Layer. 9 * 10 * The SPL is free software; you can redistribute it and/or modify it 11 * under the terms of the GNU General Public License as published by the 12 * Free Software Foundation; either version 2 of the License, or (at your 13 * option) any later version. 14 * 15 * The SPL is distributed in the hope that it will be useful, but WITHOUT 16 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 17 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 18 * for more details. 19 * 20 * You should have received a copy of the GNU General Public License along 21 * with the SPL. If not, see <http://www.gnu.org/licenses/>. 22 * 23 * Solaris Porting Layer (SPL) Generic Implementation. 24 */ 25 26 #include <sys/sysmacros.h> 27 #include <sys/systeminfo.h> 28 #include <sys/vmsystm.h> 29 #include <sys/kmem.h> 30 #include <sys/kmem_cache.h> 31 #include <sys/vmem.h> 32 #include <sys/mutex.h> 33 #include <sys/rwlock.h> 34 #include <sys/taskq.h> 35 #include <sys/tsd.h> 36 #include <sys/zmod.h> 37 #include <sys/debug.h> 38 #include <sys/proc.h> 39 #include <sys/kstat.h> 40 #include <sys/file.h> 41 #include <sys/sunddi.h> 42 #include <linux/ctype.h> 43 #include <sys/disp.h> 44 #include <sys/random.h> 45 #include <sys/strings.h> 46 #include <linux/kmod.h> 47 #include <linux/mod_compat.h> 48 #include <sys/cred.h> 49 #include <sys/vnode.h> 50 51 /* BEGIN CSTYLED */ 52 unsigned long spl_hostid = 0; 53 EXPORT_SYMBOL(spl_hostid); 54 55 module_param(spl_hostid, ulong, 0644); 56 MODULE_PARM_DESC(spl_hostid, "The system hostid."); 57 /* END CSTYLED */ 58 59 proc_t p0; 60 EXPORT_SYMBOL(p0); 61 62 /* 63 * Xorshift Pseudo Random Number Generator based on work by Sebastiano Vigna 64 * 65 * "Further scramblings of Marsaglia's xorshift generators" 66 * http://vigna.di.unimi.it/ftp/papers/xorshiftplus.pdf 67 * 68 * random_get_pseudo_bytes() is an API function on Illumos whose sole purpose 69 * is to provide bytes containing random numbers. It is mapped to /dev/urandom 70 * on Illumos, which uses a "FIPS 186-2 algorithm". No user of the SPL's 71 * random_get_pseudo_bytes() needs bytes that are of cryptographic quality, so 72 * we can implement it using a fast PRNG that we seed using Linux' actual 73 * equivalent to random_get_pseudo_bytes(). We do this by providing each CPU 74 * with an independent seed so that all calls to random_get_pseudo_bytes() are 75 * free of atomic instructions. 76 * 77 * A consequence of using a fast PRNG is that using random_get_pseudo_bytes() 78 * to generate words larger than 128 bits will paradoxically be limited to 79 * `2^128 - 1` possibilities. This is because we have a sequence of `2^128 - 1` 80 * 128-bit words and selecting the first will implicitly select the second. If 81 * a caller finds this behavior undesirable, random_get_bytes() should be used 82 * instead. 83 * 84 * XXX: Linux interrupt handlers that trigger within the critical section 85 * formed by `s[1] = xp[1];` and `xp[0] = s[0];` and call this function will 86 * see the same numbers. Nothing in the code currently calls this in an 87 * interrupt handler, so this is considered to be okay. If that becomes a 88 * problem, we could create a set of per-cpu variables for interrupt handlers 89 * and use them when in_interrupt() from linux/preempt_mask.h evaluates to 90 * true. 91 */ 92 void __percpu *spl_pseudo_entropy; 93 94 /* 95 * spl_rand_next()/spl_rand_jump() are copied from the following CC-0 licensed 96 * file: 97 * 98 * http://xorshift.di.unimi.it/xorshift128plus.c 99 */ 100 101 static inline uint64_t 102 spl_rand_next(uint64_t *s) 103 { 104 uint64_t s1 = s[0]; 105 const uint64_t s0 = s[1]; 106 s[0] = s0; 107 s1 ^= s1 << 23; // a 108 s[1] = s1 ^ s0 ^ (s1 >> 18) ^ (s0 >> 5); // b, c 109 return (s[1] + s0); 110 } 111 112 static inline void 113 spl_rand_jump(uint64_t *s) 114 { 115 static const uint64_t JUMP[] = 116 { 0x8a5cd789635d2dff, 0x121fd2155c472f96 }; 117 118 uint64_t s0 = 0; 119 uint64_t s1 = 0; 120 int i, b; 121 for (i = 0; i < sizeof (JUMP) / sizeof (*JUMP); i++) 122 for (b = 0; b < 64; b++) { 123 if (JUMP[i] & 1ULL << b) { 124 s0 ^= s[0]; 125 s1 ^= s[1]; 126 } 127 (void) spl_rand_next(s); 128 } 129 130 s[0] = s0; 131 s[1] = s1; 132 } 133 134 int 135 random_get_pseudo_bytes(uint8_t *ptr, size_t len) 136 { 137 uint64_t *xp, s[2]; 138 139 ASSERT(ptr); 140 141 xp = get_cpu_ptr(spl_pseudo_entropy); 142 143 s[0] = xp[0]; 144 s[1] = xp[1]; 145 146 while (len) { 147 union { 148 uint64_t ui64; 149 uint8_t byte[sizeof (uint64_t)]; 150 }entropy; 151 int i = MIN(len, sizeof (uint64_t)); 152 153 len -= i; 154 entropy.ui64 = spl_rand_next(s); 155 156 while (i--) 157 *ptr++ = entropy.byte[i]; 158 } 159 160 xp[0] = s[0]; 161 xp[1] = s[1]; 162 163 put_cpu_ptr(spl_pseudo_entropy); 164 165 return (0); 166 } 167 168 169 EXPORT_SYMBOL(random_get_pseudo_bytes); 170 171 #if BITS_PER_LONG == 32 172 173 /* 174 * Support 64/64 => 64 division on a 32-bit platform. While the kernel 175 * provides a div64_u64() function for this we do not use it because the 176 * implementation is flawed. There are cases which return incorrect 177 * results as late as linux-2.6.35. Until this is fixed upstream the 178 * spl must provide its own implementation. 179 * 180 * This implementation is a slightly modified version of the algorithm 181 * proposed by the book 'Hacker's Delight'. The original source can be 182 * found here and is available for use without restriction. 183 * 184 * http://www.hackersdelight.org/HDcode/newCode/divDouble.c 185 */ 186 187 /* 188 * Calculate number of leading of zeros for a 64-bit value. 189 */ 190 static int 191 nlz64(uint64_t x) 192 { 193 register int n = 0; 194 195 if (x == 0) 196 return (64); 197 198 if (x <= 0x00000000FFFFFFFFULL) { n = n + 32; x = x << 32; } 199 if (x <= 0x0000FFFFFFFFFFFFULL) { n = n + 16; x = x << 16; } 200 if (x <= 0x00FFFFFFFFFFFFFFULL) { n = n + 8; x = x << 8; } 201 if (x <= 0x0FFFFFFFFFFFFFFFULL) { n = n + 4; x = x << 4; } 202 if (x <= 0x3FFFFFFFFFFFFFFFULL) { n = n + 2; x = x << 2; } 203 if (x <= 0x7FFFFFFFFFFFFFFFULL) { n = n + 1; } 204 205 return (n); 206 } 207 208 /* 209 * Newer kernels have a div_u64() function but we define our own 210 * to simplify portability between kernel versions. 211 */ 212 static inline uint64_t 213 __div_u64(uint64_t u, uint32_t v) 214 { 215 (void) do_div(u, v); 216 return (u); 217 } 218 219 /* 220 * Turn off missing prototypes warning for these functions. They are 221 * replacements for libgcc-provided functions and will never be called 222 * directly. 223 */ 224 #pragma GCC diagnostic push 225 #pragma GCC diagnostic ignored "-Wmissing-prototypes" 226 227 /* 228 * Implementation of 64-bit unsigned division for 32-bit machines. 229 * 230 * First the procedure takes care of the case in which the divisor is a 231 * 32-bit quantity. There are two subcases: (1) If the left half of the 232 * dividend is less than the divisor, one execution of do_div() is all that 233 * is required (overflow is not possible). (2) Otherwise it does two 234 * divisions, using the grade school method. 235 */ 236 uint64_t 237 __udivdi3(uint64_t u, uint64_t v) 238 { 239 uint64_t u0, u1, v1, q0, q1, k; 240 int n; 241 242 if (v >> 32 == 0) { // If v < 2**32: 243 if (u >> 32 < v) { // If u/v cannot overflow, 244 return (__div_u64(u, v)); // just do one division. 245 } else { // If u/v would overflow: 246 u1 = u >> 32; // Break u into two halves. 247 u0 = u & 0xFFFFFFFF; 248 q1 = __div_u64(u1, v); // First quotient digit. 249 k = u1 - q1 * v; // First remainder, < v. 250 u0 += (k << 32); 251 q0 = __div_u64(u0, v); // Seconds quotient digit. 252 return ((q1 << 32) + q0); 253 } 254 } else { // If v >= 2**32: 255 n = nlz64(v); // 0 <= n <= 31. 256 v1 = (v << n) >> 32; // Normalize divisor, MSB is 1. 257 u1 = u >> 1; // To ensure no overflow. 258 q1 = __div_u64(u1, v1); // Get quotient from 259 q0 = (q1 << n) >> 31; // Undo normalization and 260 // division of u by 2. 261 if (q0 != 0) // Make q0 correct or 262 q0 = q0 - 1; // too small by 1. 263 if ((u - q0 * v) >= v) 264 q0 = q0 + 1; // Now q0 is correct. 265 266 return (q0); 267 } 268 } 269 EXPORT_SYMBOL(__udivdi3); 270 271 /* BEGIN CSTYLED */ 272 #ifndef abs64 273 #define abs64(x) ({ uint64_t t = (x) >> 63; ((x) ^ t) - t; }) 274 #endif 275 /* END CSTYLED */ 276 277 /* 278 * Implementation of 64-bit signed division for 32-bit machines. 279 */ 280 int64_t 281 __divdi3(int64_t u, int64_t v) 282 { 283 int64_t q, t; 284 q = __udivdi3(abs64(u), abs64(v)); 285 t = (u ^ v) >> 63; // If u, v have different 286 return ((q ^ t) - t); // signs, negate q. 287 } 288 EXPORT_SYMBOL(__divdi3); 289 290 /* 291 * Implementation of 64-bit unsigned modulo for 32-bit machines. 292 */ 293 uint64_t 294 __umoddi3(uint64_t dividend, uint64_t divisor) 295 { 296 return (dividend - (divisor * __udivdi3(dividend, divisor))); 297 } 298 EXPORT_SYMBOL(__umoddi3); 299 300 /* 64-bit signed modulo for 32-bit machines. */ 301 int64_t 302 __moddi3(int64_t n, int64_t d) 303 { 304 int64_t q; 305 boolean_t nn = B_FALSE; 306 307 if (n < 0) { 308 nn = B_TRUE; 309 n = -n; 310 } 311 if (d < 0) 312 d = -d; 313 314 q = __umoddi3(n, d); 315 316 return (nn ? -q : q); 317 } 318 EXPORT_SYMBOL(__moddi3); 319 320 /* 321 * Implementation of 64-bit unsigned division/modulo for 32-bit machines. 322 */ 323 uint64_t 324 __udivmoddi4(uint64_t n, uint64_t d, uint64_t *r) 325 { 326 uint64_t q = __udivdi3(n, d); 327 if (r) 328 *r = n - d * q; 329 return (q); 330 } 331 EXPORT_SYMBOL(__udivmoddi4); 332 333 /* 334 * Implementation of 64-bit signed division/modulo for 32-bit machines. 335 */ 336 int64_t 337 __divmoddi4(int64_t n, int64_t d, int64_t *r) 338 { 339 int64_t q, rr; 340 boolean_t nn = B_FALSE; 341 boolean_t nd = B_FALSE; 342 if (n < 0) { 343 nn = B_TRUE; 344 n = -n; 345 } 346 if (d < 0) { 347 nd = B_TRUE; 348 d = -d; 349 } 350 351 q = __udivmoddi4(n, d, (uint64_t *)&rr); 352 353 if (nn != nd) 354 q = -q; 355 if (nn) 356 rr = -rr; 357 if (r) 358 *r = rr; 359 return (q); 360 } 361 EXPORT_SYMBOL(__divmoddi4); 362 363 #if defined(__arm) || defined(__arm__) 364 /* 365 * Implementation of 64-bit (un)signed division for 32-bit arm machines. 366 * 367 * Run-time ABI for the ARM Architecture (page 20). A pair of (unsigned) 368 * long longs is returned in {{r0, r1}, {r2,r3}}, the quotient in {r0, r1}, 369 * and the remainder in {r2, r3}. The return type is specifically left 370 * set to 'void' to ensure the compiler does not overwrite these registers 371 * during the return. All results are in registers as per ABI 372 */ 373 void 374 __aeabi_uldivmod(uint64_t u, uint64_t v) 375 { 376 uint64_t res; 377 uint64_t mod; 378 379 res = __udivdi3(u, v); 380 mod = __umoddi3(u, v); 381 { 382 register uint32_t r0 asm("r0") = (res & 0xFFFFFFFF); 383 register uint32_t r1 asm("r1") = (res >> 32); 384 register uint32_t r2 asm("r2") = (mod & 0xFFFFFFFF); 385 register uint32_t r3 asm("r3") = (mod >> 32); 386 387 /* BEGIN CSTYLED */ 388 asm volatile("" 389 : "+r"(r0), "+r"(r1), "+r"(r2),"+r"(r3) /* output */ 390 : "r"(r0), "r"(r1), "r"(r2), "r"(r3)); /* input */ 391 /* END CSTYLED */ 392 393 return; /* r0; */ 394 } 395 } 396 EXPORT_SYMBOL(__aeabi_uldivmod); 397 398 void 399 __aeabi_ldivmod(int64_t u, int64_t v) 400 { 401 int64_t res; 402 uint64_t mod; 403 404 res = __divdi3(u, v); 405 mod = __umoddi3(u, v); 406 { 407 register uint32_t r0 asm("r0") = (res & 0xFFFFFFFF); 408 register uint32_t r1 asm("r1") = (res >> 32); 409 register uint32_t r2 asm("r2") = (mod & 0xFFFFFFFF); 410 register uint32_t r3 asm("r3") = (mod >> 32); 411 412 /* BEGIN CSTYLED */ 413 asm volatile("" 414 : "+r"(r0), "+r"(r1), "+r"(r2),"+r"(r3) /* output */ 415 : "r"(r0), "r"(r1), "r"(r2), "r"(r3)); /* input */ 416 /* END CSTYLED */ 417 418 return; /* r0; */ 419 } 420 } 421 EXPORT_SYMBOL(__aeabi_ldivmod); 422 #endif /* __arm || __arm__ */ 423 424 #pragma GCC diagnostic pop 425 426 #endif /* BITS_PER_LONG */ 427 428 /* 429 * NOTE: The strtoxx behavior is solely based on my reading of the Solaris 430 * ddi_strtol(9F) man page. I have not verified the behavior of these 431 * functions against their Solaris counterparts. It is possible that I 432 * may have misinterpreted the man page or the man page is incorrect. 433 */ 434 int ddi_strtoul(const char *, char **, int, unsigned long *); 435 int ddi_strtol(const char *, char **, int, long *); 436 int ddi_strtoull(const char *, char **, int, unsigned long long *); 437 int ddi_strtoll(const char *, char **, int, long long *); 438 439 #define define_ddi_strtoux(type, valtype) \ 440 int ddi_strtou##type(const char *str, char **endptr, \ 441 int base, valtype *result) \ 442 { \ 443 valtype last_value, value = 0; \ 444 char *ptr = (char *)str; \ 445 int flag = 1, digit; \ 446 \ 447 if (strlen(ptr) == 0) \ 448 return (EINVAL); \ 449 \ 450 /* Auto-detect base based on prefix */ \ 451 if (!base) { \ 452 if (str[0] == '0') { \ 453 if (tolower(str[1]) == 'x' && isxdigit(str[2])) { \ 454 base = 16; /* hex */ \ 455 ptr += 2; \ 456 } else if (str[1] >= '0' && str[1] < 8) { \ 457 base = 8; /* octal */ \ 458 ptr += 1; \ 459 } else { \ 460 return (EINVAL); \ 461 } \ 462 } else { \ 463 base = 10; /* decimal */ \ 464 } \ 465 } \ 466 \ 467 while (1) { \ 468 if (isdigit(*ptr)) \ 469 digit = *ptr - '0'; \ 470 else if (isalpha(*ptr)) \ 471 digit = tolower(*ptr) - 'a' + 10; \ 472 else \ 473 break; \ 474 \ 475 if (digit >= base) \ 476 break; \ 477 \ 478 last_value = value; \ 479 value = value * base + digit; \ 480 if (last_value > value) /* Overflow */ \ 481 return (ERANGE); \ 482 \ 483 flag = 1; \ 484 ptr++; \ 485 } \ 486 \ 487 if (flag) \ 488 *result = value; \ 489 \ 490 if (endptr) \ 491 *endptr = (char *)(flag ? ptr : str); \ 492 \ 493 return (0); \ 494 } \ 495 496 #define define_ddi_strtox(type, valtype) \ 497 int ddi_strto##type(const char *str, char **endptr, \ 498 int base, valtype *result) \ 499 { \ 500 int rc; \ 501 \ 502 if (*str == '-') { \ 503 rc = ddi_strtou##type(str + 1, endptr, base, result); \ 504 if (!rc) { \ 505 if (*endptr == str + 1) \ 506 *endptr = (char *)str; \ 507 else \ 508 *result = -*result; \ 509 } \ 510 } else { \ 511 rc = ddi_strtou##type(str, endptr, base, result); \ 512 } \ 513 \ 514 return (rc); \ 515 } 516 517 define_ddi_strtoux(l, unsigned long) 518 define_ddi_strtox(l, long) 519 define_ddi_strtoux(ll, unsigned long long) 520 define_ddi_strtox(ll, long long) 521 522 EXPORT_SYMBOL(ddi_strtoul); 523 EXPORT_SYMBOL(ddi_strtol); 524 EXPORT_SYMBOL(ddi_strtoll); 525 EXPORT_SYMBOL(ddi_strtoull); 526 527 int 528 ddi_copyin(const void *from, void *to, size_t len, int flags) 529 { 530 /* Fake ioctl() issued by kernel, 'from' is a kernel address */ 531 if (flags & FKIOCTL) { 532 memcpy(to, from, len); 533 return (0); 534 } 535 536 return (copyin(from, to, len)); 537 } 538 EXPORT_SYMBOL(ddi_copyin); 539 540 int 541 ddi_copyout(const void *from, void *to, size_t len, int flags) 542 { 543 /* Fake ioctl() issued by kernel, 'from' is a kernel address */ 544 if (flags & FKIOCTL) { 545 memcpy(to, from, len); 546 return (0); 547 } 548 549 return (copyout(from, to, len)); 550 } 551 EXPORT_SYMBOL(ddi_copyout); 552 553 static ssize_t 554 spl_kernel_read(struct file *file, void *buf, size_t count, loff_t *pos) 555 { 556 #if defined(HAVE_KERNEL_READ_PPOS) 557 return (kernel_read(file, buf, count, pos)); 558 #else 559 mm_segment_t saved_fs; 560 ssize_t ret; 561 562 saved_fs = get_fs(); 563 set_fs(KERNEL_DS); 564 565 ret = vfs_read(file, (void __user *)buf, count, pos); 566 567 set_fs(saved_fs); 568 569 return (ret); 570 #endif 571 } 572 573 static int 574 spl_getattr(struct file *filp, struct kstat *stat) 575 { 576 int rc; 577 578 ASSERT(filp); 579 ASSERT(stat); 580 581 #if defined(HAVE_4ARGS_VFS_GETATTR) 582 rc = vfs_getattr(&filp->f_path, stat, STATX_BASIC_STATS, 583 AT_STATX_SYNC_AS_STAT); 584 #elif defined(HAVE_2ARGS_VFS_GETATTR) 585 rc = vfs_getattr(&filp->f_path, stat); 586 #elif defined(HAVE_3ARGS_VFS_GETATTR) 587 rc = vfs_getattr(filp->f_path.mnt, filp->f_dentry, stat); 588 #else 589 #error "No available vfs_getattr()" 590 #endif 591 if (rc) 592 return (-rc); 593 594 return (0); 595 } 596 597 /* 598 * Read the unique system identifier from the /etc/hostid file. 599 * 600 * The behavior of /usr/bin/hostid on Linux systems with the 601 * regular eglibc and coreutils is: 602 * 603 * 1. Generate the value if the /etc/hostid file does not exist 604 * or if the /etc/hostid file is less than four bytes in size. 605 * 606 * 2. If the /etc/hostid file is at least 4 bytes, then return 607 * the first four bytes [0..3] in native endian order. 608 * 609 * 3. Always ignore bytes [4..] if they exist in the file. 610 * 611 * Only the first four bytes are significant, even on systems that 612 * have a 64-bit word size. 613 * 614 * See: 615 * 616 * eglibc: sysdeps/unix/sysv/linux/gethostid.c 617 * coreutils: src/hostid.c 618 * 619 * Notes: 620 * 621 * The /etc/hostid file on Solaris is a text file that often reads: 622 * 623 * # DO NOT EDIT 624 * "0123456789" 625 * 626 * Directly copying this file to Linux results in a constant 627 * hostid of 4f442023 because the default comment constitutes 628 * the first four bytes of the file. 629 * 630 */ 631 632 static char *spl_hostid_path = HW_HOSTID_PATH; 633 module_param(spl_hostid_path, charp, 0444); 634 MODULE_PARM_DESC(spl_hostid_path, "The system hostid file (/etc/hostid)"); 635 636 static int 637 hostid_read(uint32_t *hostid) 638 { 639 uint64_t size; 640 uint32_t value = 0; 641 int error; 642 loff_t off; 643 struct file *filp; 644 struct kstat stat; 645 646 filp = filp_open(spl_hostid_path, 0, 0); 647 648 if (IS_ERR(filp)) 649 return (ENOENT); 650 651 error = spl_getattr(filp, &stat); 652 if (error) { 653 filp_close(filp, 0); 654 return (error); 655 } 656 size = stat.size; 657 // cppcheck-suppress sizeofwithnumericparameter 658 if (size < sizeof (HW_HOSTID_MASK)) { 659 filp_close(filp, 0); 660 return (EINVAL); 661 } 662 663 off = 0; 664 /* 665 * Read directly into the variable like eglibc does. 666 * Short reads are okay; native behavior is preserved. 667 */ 668 error = spl_kernel_read(filp, &value, sizeof (value), &off); 669 if (error < 0) { 670 filp_close(filp, 0); 671 return (EIO); 672 } 673 674 /* Mask down to 32 bits like coreutils does. */ 675 *hostid = (value & HW_HOSTID_MASK); 676 filp_close(filp, 0); 677 678 return (0); 679 } 680 681 /* 682 * Return the system hostid. Preferentially use the spl_hostid module option 683 * when set, otherwise use the value in the /etc/hostid file. 684 */ 685 uint32_t 686 zone_get_hostid(void *zone) 687 { 688 uint32_t hostid; 689 690 ASSERT3P(zone, ==, NULL); 691 692 if (spl_hostid != 0) 693 return ((uint32_t)(spl_hostid & HW_HOSTID_MASK)); 694 695 if (hostid_read(&hostid) == 0) 696 return (hostid); 697 698 return (0); 699 } 700 EXPORT_SYMBOL(zone_get_hostid); 701 702 static int 703 spl_kvmem_init(void) 704 { 705 int rc = 0; 706 707 rc = spl_kmem_init(); 708 if (rc) 709 return (rc); 710 711 rc = spl_vmem_init(); 712 if (rc) { 713 spl_kmem_fini(); 714 return (rc); 715 } 716 717 return (rc); 718 } 719 720 /* 721 * We initialize the random number generator with 128 bits of entropy from the 722 * system random number generator. In the improbable case that we have a zero 723 * seed, we fallback to the system jiffies, unless it is also zero, in which 724 * situation we use a preprogrammed seed. We step forward by 2^64 iterations to 725 * initialize each of the per-cpu seeds so that the sequences generated on each 726 * CPU are guaranteed to never overlap in practice. 727 */ 728 static void __init 729 spl_random_init(void) 730 { 731 uint64_t s[2]; 732 int i = 0; 733 734 spl_pseudo_entropy = __alloc_percpu(2 * sizeof (uint64_t), 735 sizeof (uint64_t)); 736 737 get_random_bytes(s, sizeof (s)); 738 739 if (s[0] == 0 && s[1] == 0) { 740 if (jiffies != 0) { 741 s[0] = jiffies; 742 s[1] = ~0 - jiffies; 743 } else { 744 (void) memcpy(s, "improbable seed", sizeof (s)); 745 } 746 printk("SPL: get_random_bytes() returned 0 " 747 "when generating random seed. Setting initial seed to " 748 "0x%016llx%016llx.\n", cpu_to_be64(s[0]), 749 cpu_to_be64(s[1])); 750 } 751 752 for_each_possible_cpu(i) { 753 uint64_t *wordp = per_cpu_ptr(spl_pseudo_entropy, i); 754 755 spl_rand_jump(s); 756 757 wordp[0] = s[0]; 758 wordp[1] = s[1]; 759 } 760 } 761 762 static void 763 spl_random_fini(void) 764 { 765 free_percpu(spl_pseudo_entropy); 766 } 767 768 static void 769 spl_kvmem_fini(void) 770 { 771 spl_vmem_fini(); 772 spl_kmem_fini(); 773 } 774 775 static int __init 776 spl_init(void) 777 { 778 int rc = 0; 779 780 bzero(&p0, sizeof (proc_t)); 781 spl_random_init(); 782 783 if ((rc = spl_kvmem_init())) 784 goto out1; 785 786 if ((rc = spl_tsd_init())) 787 goto out2; 788 789 if ((rc = spl_taskq_init())) 790 goto out3; 791 792 if ((rc = spl_kmem_cache_init())) 793 goto out4; 794 795 if ((rc = spl_proc_init())) 796 goto out5; 797 798 if ((rc = spl_kstat_init())) 799 goto out6; 800 801 if ((rc = spl_zlib_init())) 802 goto out7; 803 804 return (rc); 805 806 out7: 807 spl_kstat_fini(); 808 out6: 809 spl_proc_fini(); 810 out5: 811 spl_kmem_cache_fini(); 812 out4: 813 spl_taskq_fini(); 814 out3: 815 spl_tsd_fini(); 816 out2: 817 spl_kvmem_fini(); 818 out1: 819 return (rc); 820 } 821 822 static void __exit 823 spl_fini(void) 824 { 825 spl_zlib_fini(); 826 spl_kstat_fini(); 827 spl_proc_fini(); 828 spl_kmem_cache_fini(); 829 spl_taskq_fini(); 830 spl_tsd_fini(); 831 spl_kvmem_fini(); 832 spl_random_fini(); 833 } 834 835 module_init(spl_init); 836 module_exit(spl_fini); 837 838 ZFS_MODULE_DESCRIPTION("Solaris Porting Layer"); 839 ZFS_MODULE_AUTHOR(ZFS_META_AUTHOR); 840 ZFS_MODULE_LICENSE("GPL"); 841 ZFS_MODULE_VERSION(ZFS_META_VERSION "-" ZFS_META_RELEASE); 842