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 <[email protected]>.
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 "zfs_gitrev.h"
48 #include <linux/mod_compat.h>
49 #include <sys/cred.h>
50 #include <sys/vnode.h>
51
52 char spl_gitrev[64] = ZFS_META_GITREV;
53
54 /* BEGIN CSTYLED */
55 unsigned long spl_hostid = 0;
56 EXPORT_SYMBOL(spl_hostid);
57 /* BEGIN CSTYLED */
58 module_param(spl_hostid, ulong, 0644);
59 MODULE_PARM_DESC(spl_hostid, "The system hostid.");
60 /* END CSTYLED */
61
62 proc_t p0;
63 EXPORT_SYMBOL(p0);
64
65 /*
66 * Xorshift Pseudo Random Number Generator based on work by Sebastiano Vigna
67 *
68 * "Further scramblings of Marsaglia's xorshift generators"
69 * http://vigna.di.unimi.it/ftp/papers/xorshiftplus.pdf
70 *
71 * random_get_pseudo_bytes() is an API function on Illumos whose sole purpose
72 * is to provide bytes containing random numbers. It is mapped to /dev/urandom
73 * on Illumos, which uses a "FIPS 186-2 algorithm". No user of the SPL's
74 * random_get_pseudo_bytes() needs bytes that are of cryptographic quality, so
75 * we can implement it using a fast PRNG that we seed using Linux' actual
76 * equivalent to random_get_pseudo_bytes(). We do this by providing each CPU
77 * with an independent seed so that all calls to random_get_pseudo_bytes() are
78 * free of atomic instructions.
79 *
80 * A consequence of using a fast PRNG is that using random_get_pseudo_bytes()
81 * to generate words larger than 128 bits will paradoxically be limited to
82 * `2^128 - 1` possibilities. This is because we have a sequence of `2^128 - 1`
83 * 128-bit words and selecting the first will implicitly select the second. If
84 * a caller finds this behavior undesirable, random_get_bytes() should be used
85 * instead.
86 *
87 * XXX: Linux interrupt handlers that trigger within the critical section
88 * formed by `s[1] = xp[1];` and `xp[0] = s[0];` and call this function will
89 * see the same numbers. Nothing in the code currently calls this in an
90 * interrupt handler, so this is considered to be okay. If that becomes a
91 * problem, we could create a set of per-cpu variables for interrupt handlers
92 * and use them when in_interrupt() from linux/preempt_mask.h evaluates to
93 * true.
94 */
95 void __percpu *spl_pseudo_entropy;
96
97 /*
98 * spl_rand_next()/spl_rand_jump() are copied from the following CC-0 licensed
99 * file:
100 *
101 * http://xorshift.di.unimi.it/xorshift128plus.c
102 */
103
104 static inline uint64_t
spl_rand_next(uint64_t * s)105 spl_rand_next(uint64_t *s)
106 {
107 uint64_t s1 = s[0];
108 const uint64_t s0 = s[1];
109 s[0] = s0;
110 s1 ^= s1 << 23; // a
111 s[1] = s1 ^ s0 ^ (s1 >> 18) ^ (s0 >> 5); // b, c
112 return (s[1] + s0);
113 }
114
115 static inline void
spl_rand_jump(uint64_t * s)116 spl_rand_jump(uint64_t *s)
117 {
118 static const uint64_t JUMP[] =
119 { 0x8a5cd789635d2dff, 0x121fd2155c472f96 };
120
121 uint64_t s0 = 0;
122 uint64_t s1 = 0;
123 int i, b;
124 for (i = 0; i < sizeof (JUMP) / sizeof (*JUMP); i++)
125 for (b = 0; b < 64; b++) {
126 if (JUMP[i] & 1ULL << b) {
127 s0 ^= s[0];
128 s1 ^= s[1];
129 }
130 (void) spl_rand_next(s);
131 }
132
133 s[0] = s0;
134 s[1] = s1;
135 }
136
137 int
random_get_pseudo_bytes(uint8_t * ptr,size_t len)138 random_get_pseudo_bytes(uint8_t *ptr, size_t len)
139 {
140 uint64_t *xp, s[2];
141
142 ASSERT(ptr);
143
144 xp = get_cpu_ptr(spl_pseudo_entropy);
145
146 s[0] = xp[0];
147 s[1] = xp[1];
148
149 while (len) {
150 union {
151 uint64_t ui64;
152 uint8_t byte[sizeof (uint64_t)];
153 }entropy;
154 int i = MIN(len, sizeof (uint64_t));
155
156 len -= i;
157 entropy.ui64 = spl_rand_next(s);
158
159 while (i--)
160 *ptr++ = entropy.byte[i];
161 }
162
163 xp[0] = s[0];
164 xp[1] = s[1];
165
166 put_cpu_ptr(spl_pseudo_entropy);
167
168 return (0);
169 }
170
171
172 EXPORT_SYMBOL(random_get_pseudo_bytes);
173
174 #if BITS_PER_LONG == 32
175
176 /*
177 * Support 64/64 => 64 division on a 32-bit platform. While the kernel
178 * provides a div64_u64() function for this we do not use it because the
179 * implementation is flawed. There are cases which return incorrect
180 * results as late as linux-2.6.35. Until this is fixed upstream the
181 * spl must provide its own implementation.
182 *
183 * This implementation is a slightly modified version of the algorithm
184 * proposed by the book 'Hacker's Delight'. The original source can be
185 * found here and is available for use without restriction.
186 *
187 * http://www.hackersdelight.org/HDcode/newCode/divDouble.c
188 */
189
190 /*
191 * Calculate number of leading of zeros for a 64-bit value.
192 */
193 static int
nlz64(uint64_t x)194 nlz64(uint64_t x)
195 {
196 register int n = 0;
197
198 if (x == 0)
199 return (64);
200
201 if (x <= 0x00000000FFFFFFFFULL) { n = n + 32; x = x << 32; }
202 if (x <= 0x0000FFFFFFFFFFFFULL) { n = n + 16; x = x << 16; }
203 if (x <= 0x00FFFFFFFFFFFFFFULL) { n = n + 8; x = x << 8; }
204 if (x <= 0x0FFFFFFFFFFFFFFFULL) { n = n + 4; x = x << 4; }
205 if (x <= 0x3FFFFFFFFFFFFFFFULL) { n = n + 2; x = x << 2; }
206 if (x <= 0x7FFFFFFFFFFFFFFFULL) { n = n + 1; }
207
208 return (n);
209 }
210
211 /*
212 * Newer kernels have a div_u64() function but we define our own
213 * to simplify portability between kernel versions.
214 */
215 static inline uint64_t
__div_u64(uint64_t u,uint32_t v)216 __div_u64(uint64_t u, uint32_t v)
217 {
218 (void) do_div(u, v);
219 return (u);
220 }
221
222 /*
223 * Turn off missing prototypes warning for these functions. They are
224 * replacements for libgcc-provided functions and will never be called
225 * directly.
226 */
227 #pragma GCC diagnostic push
228 #pragma GCC diagnostic ignored "-Wmissing-prototypes"
229
230 /*
231 * Implementation of 64-bit unsigned division for 32-bit machines.
232 *
233 * First the procedure takes care of the case in which the divisor is a
234 * 32-bit quantity. There are two subcases: (1) If the left half of the
235 * dividend is less than the divisor, one execution of do_div() is all that
236 * is required (overflow is not possible). (2) Otherwise it does two
237 * divisions, using the grade school method.
238 */
239 uint64_t
__udivdi3(uint64_t u,uint64_t v)240 __udivdi3(uint64_t u, uint64_t v)
241 {
242 uint64_t u0, u1, v1, q0, q1, k;
243 int n;
244
245 if (v >> 32 == 0) { // If v < 2**32:
246 if (u >> 32 < v) { // If u/v cannot overflow,
247 return (__div_u64(u, v)); // just do one division.
248 } else { // If u/v would overflow:
249 u1 = u >> 32; // Break u into two halves.
250 u0 = u & 0xFFFFFFFF;
251 q1 = __div_u64(u1, v); // First quotient digit.
252 k = u1 - q1 * v; // First remainder, < v.
253 u0 += (k << 32);
254 q0 = __div_u64(u0, v); // Seconds quotient digit.
255 return ((q1 << 32) + q0);
256 }
257 } else { // If v >= 2**32:
258 n = nlz64(v); // 0 <= n <= 31.
259 v1 = (v << n) >> 32; // Normalize divisor, MSB is 1.
260 u1 = u >> 1; // To ensure no overflow.
261 q1 = __div_u64(u1, v1); // Get quotient from
262 q0 = (q1 << n) >> 31; // Undo normalization and
263 // division of u by 2.
264 if (q0 != 0) // Make q0 correct or
265 q0 = q0 - 1; // too small by 1.
266 if ((u - q0 * v) >= v)
267 q0 = q0 + 1; // Now q0 is correct.
268
269 return (q0);
270 }
271 }
272 EXPORT_SYMBOL(__udivdi3);
273
274 /* BEGIN CSTYLED */
275 #ifndef abs64
276 #define abs64(x) ({ uint64_t t = (x) >> 63; ((x) ^ t) - t; })
277 #endif
278 /* END CSTYLED */
279
280 /*
281 * Implementation of 64-bit signed division for 32-bit machines.
282 */
283 int64_t
__divdi3(int64_t u,int64_t v)284 __divdi3(int64_t u, int64_t v)
285 {
286 int64_t q, t;
287 // cppcheck-suppress shiftTooManyBitsSigned
288 q = __udivdi3(abs64(u), abs64(v));
289 // cppcheck-suppress shiftTooManyBitsSigned
290 t = (u ^ v) >> 63; // If u, v have different
291 return ((q ^ t) - t); // signs, negate q.
292 }
293 EXPORT_SYMBOL(__divdi3);
294
295 /*
296 * Implementation of 64-bit unsigned modulo for 32-bit machines.
297 */
298 uint64_t
__umoddi3(uint64_t dividend,uint64_t divisor)299 __umoddi3(uint64_t dividend, uint64_t divisor)
300 {
301 return (dividend - (divisor * __udivdi3(dividend, divisor)));
302 }
303 EXPORT_SYMBOL(__umoddi3);
304
305 /* 64-bit signed modulo for 32-bit machines. */
306 int64_t
__moddi3(int64_t n,int64_t d)307 __moddi3(int64_t n, int64_t d)
308 {
309 int64_t q;
310 boolean_t nn = B_FALSE;
311
312 if (n < 0) {
313 nn = B_TRUE;
314 n = -n;
315 }
316 if (d < 0)
317 d = -d;
318
319 q = __umoddi3(n, d);
320
321 return (nn ? -q : q);
322 }
323 EXPORT_SYMBOL(__moddi3);
324
325 /*
326 * Implementation of 64-bit unsigned division/modulo for 32-bit machines.
327 */
328 uint64_t
__udivmoddi4(uint64_t n,uint64_t d,uint64_t * r)329 __udivmoddi4(uint64_t n, uint64_t d, uint64_t *r)
330 {
331 uint64_t q = __udivdi3(n, d);
332 if (r)
333 *r = n - d * q;
334 return (q);
335 }
336 EXPORT_SYMBOL(__udivmoddi4);
337
338 /*
339 * Implementation of 64-bit signed division/modulo for 32-bit machines.
340 */
341 int64_t
__divmoddi4(int64_t n,int64_t d,int64_t * r)342 __divmoddi4(int64_t n, int64_t d, int64_t *r)
343 {
344 int64_t q, rr;
345 boolean_t nn = B_FALSE;
346 boolean_t nd = B_FALSE;
347 if (n < 0) {
348 nn = B_TRUE;
349 n = -n;
350 }
351 if (d < 0) {
352 nd = B_TRUE;
353 d = -d;
354 }
355
356 q = __udivmoddi4(n, d, (uint64_t *)&rr);
357
358 if (nn != nd)
359 q = -q;
360 if (nn)
361 rr = -rr;
362 if (r)
363 *r = rr;
364 return (q);
365 }
366 EXPORT_SYMBOL(__divmoddi4);
367
368 #if defined(__arm) || defined(__arm__)
369 /*
370 * Implementation of 64-bit (un)signed division for 32-bit arm machines.
371 *
372 * Run-time ABI for the ARM Architecture (page 20). A pair of (unsigned)
373 * long longs is returned in {{r0, r1}, {r2,r3}}, the quotient in {r0, r1},
374 * and the remainder in {r2, r3}. The return type is specifically left
375 * set to 'void' to ensure the compiler does not overwrite these registers
376 * during the return. All results are in registers as per ABI
377 */
378 void
__aeabi_uldivmod(uint64_t u,uint64_t v)379 __aeabi_uldivmod(uint64_t u, uint64_t v)
380 {
381 uint64_t res;
382 uint64_t mod;
383
384 res = __udivdi3(u, v);
385 mod = __umoddi3(u, v);
386 {
387 register uint32_t r0 asm("r0") = (res & 0xFFFFFFFF);
388 register uint32_t r1 asm("r1") = (res >> 32);
389 register uint32_t r2 asm("r2") = (mod & 0xFFFFFFFF);
390 register uint32_t r3 asm("r3") = (mod >> 32);
391
392 /* BEGIN CSTYLED */
393 asm volatile(""
394 : "+r"(r0), "+r"(r1), "+r"(r2),"+r"(r3) /* output */
395 : "r"(r0), "r"(r1), "r"(r2), "r"(r3)); /* input */
396 /* END CSTYLED */
397
398 return; /* r0; */
399 }
400 }
401 EXPORT_SYMBOL(__aeabi_uldivmod);
402
403 void
__aeabi_ldivmod(int64_t u,int64_t v)404 __aeabi_ldivmod(int64_t u, int64_t v)
405 {
406 int64_t res;
407 uint64_t mod;
408
409 res = __divdi3(u, v);
410 mod = __umoddi3(u, v);
411 {
412 register uint32_t r0 asm("r0") = (res & 0xFFFFFFFF);
413 register uint32_t r1 asm("r1") = (res >> 32);
414 register uint32_t r2 asm("r2") = (mod & 0xFFFFFFFF);
415 register uint32_t r3 asm("r3") = (mod >> 32);
416
417 /* BEGIN CSTYLED */
418 asm volatile(""
419 : "+r"(r0), "+r"(r1), "+r"(r2),"+r"(r3) /* output */
420 : "r"(r0), "r"(r1), "r"(r2), "r"(r3)); /* input */
421 /* END CSTYLED */
422
423 return; /* r0; */
424 }
425 }
426 EXPORT_SYMBOL(__aeabi_ldivmod);
427 #endif /* __arm || __arm__ */
428
429 #pragma GCC diagnostic pop
430
431 #endif /* BITS_PER_LONG */
432
433 /*
434 * NOTE: The strtoxx behavior is solely based on my reading of the Solaris
435 * ddi_strtol(9F) man page. I have not verified the behavior of these
436 * functions against their Solaris counterparts. It is possible that I
437 * may have misinterpreted the man page or the man page is incorrect.
438 */
439 int ddi_strtoul(const char *, char **, int, unsigned long *);
440 int ddi_strtol(const char *, char **, int, long *);
441 int ddi_strtoull(const char *, char **, int, unsigned long long *);
442 int ddi_strtoll(const char *, char **, int, long long *);
443
444 #define define_ddi_strtoux(type, valtype) \
445 int ddi_strtou##type(const char *str, char **endptr, \
446 int base, valtype *result) \
447 { \
448 valtype last_value, value = 0; \
449 char *ptr = (char *)str; \
450 int flag = 1, digit; \
451 \
452 if (strlen(ptr) == 0) \
453 return (EINVAL); \
454 \
455 /* Auto-detect base based on prefix */ \
456 if (!base) { \
457 if (str[0] == '0') { \
458 if (tolower(str[1]) == 'x' && isxdigit(str[2])) { \
459 base = 16; /* hex */ \
460 ptr += 2; \
461 } else if (str[1] >= '0' && str[1] < 8) { \
462 base = 8; /* octal */ \
463 ptr += 1; \
464 } else { \
465 return (EINVAL); \
466 } \
467 } else { \
468 base = 10; /* decimal */ \
469 } \
470 } \
471 \
472 while (1) { \
473 if (isdigit(*ptr)) \
474 digit = *ptr - '0'; \
475 else if (isalpha(*ptr)) \
476 digit = tolower(*ptr) - 'a' + 10; \
477 else \
478 break; \
479 \
480 if (digit >= base) \
481 break; \
482 \
483 last_value = value; \
484 value = value * base + digit; \
485 if (last_value > value) /* Overflow */ \
486 return (ERANGE); \
487 \
488 flag = 1; \
489 ptr++; \
490 } \
491 \
492 if (flag) \
493 *result = value; \
494 \
495 if (endptr) \
496 *endptr = (char *)(flag ? ptr : str); \
497 \
498 return (0); \
499 } \
500
501 #define define_ddi_strtox(type, valtype) \
502 int ddi_strto##type(const char *str, char **endptr, \
503 int base, valtype *result) \
504 { \
505 int rc; \
506 \
507 if (*str == '-') { \
508 rc = ddi_strtou##type(str + 1, endptr, base, result); \
509 if (!rc) { \
510 if (*endptr == str + 1) \
511 *endptr = (char *)str; \
512 else \
513 *result = -*result; \
514 } \
515 } else { \
516 rc = ddi_strtou##type(str, endptr, base, result); \
517 } \
518 \
519 return (rc); \
520 }
521
522 define_ddi_strtoux(l, unsigned long)
523 define_ddi_strtox(l, long)
524 define_ddi_strtoux(ll, unsigned long long)
525 define_ddi_strtox(ll, long long)
526
527 EXPORT_SYMBOL(ddi_strtoul);
528 EXPORT_SYMBOL(ddi_strtol);
529 EXPORT_SYMBOL(ddi_strtoll);
530 EXPORT_SYMBOL(ddi_strtoull);
531
532 int
ddi_copyin(const void * from,void * to,size_t len,int flags)533 ddi_copyin(const void *from, void *to, size_t len, int flags)
534 {
535 /* Fake ioctl() issued by kernel, 'from' is a kernel address */
536 if (flags & FKIOCTL) {
537 memcpy(to, from, len);
538 return (0);
539 }
540
541 return (copyin(from, to, len));
542 }
543 EXPORT_SYMBOL(ddi_copyin);
544
545 int
ddi_copyout(const void * from,void * to,size_t len,int flags)546 ddi_copyout(const void *from, void *to, size_t len, int flags)
547 {
548 /* Fake ioctl() issued by kernel, 'from' is a kernel address */
549 if (flags & FKIOCTL) {
550 memcpy(to, from, len);
551 return (0);
552 }
553
554 return (copyout(from, to, len));
555 }
556 EXPORT_SYMBOL(ddi_copyout);
557
558 static ssize_t
spl_kernel_read(struct file * file,void * buf,size_t count,loff_t * pos)559 spl_kernel_read(struct file *file, void *buf, size_t count, loff_t *pos)
560 {
561 #if defined(HAVE_KERNEL_READ_PPOS)
562 return (kernel_read(file, buf, count, pos));
563 #else
564 mm_segment_t saved_fs;
565 ssize_t ret;
566
567 saved_fs = get_fs();
568 set_fs(KERNEL_DS);
569
570 ret = vfs_read(file, (void __user *)buf, count, pos);
571
572 set_fs(saved_fs);
573
574 return (ret);
575 #endif
576 }
577
578 static int
spl_getattr(struct file * filp,struct kstat * stat)579 spl_getattr(struct file *filp, struct kstat *stat)
580 {
581 int rc;
582
583 ASSERT(filp);
584 ASSERT(stat);
585
586 #if defined(HAVE_4ARGS_VFS_GETATTR)
587 rc = vfs_getattr(&filp->f_path, stat, STATX_BASIC_STATS,
588 AT_STATX_SYNC_AS_STAT);
589 #elif defined(HAVE_2ARGS_VFS_GETATTR)
590 rc = vfs_getattr(&filp->f_path, stat);
591 #else
592 rc = vfs_getattr(filp->f_path.mnt, filp->f_dentry, stat);
593 #endif
594 if (rc)
595 return (-rc);
596
597 return (0);
598 }
599
600 /*
601 * Read the unique system identifier from the /etc/hostid file.
602 *
603 * The behavior of /usr/bin/hostid on Linux systems with the
604 * regular eglibc and coreutils is:
605 *
606 * 1. Generate the value if the /etc/hostid file does not exist
607 * or if the /etc/hostid file is less than four bytes in size.
608 *
609 * 2. If the /etc/hostid file is at least 4 bytes, then return
610 * the first four bytes [0..3] in native endian order.
611 *
612 * 3. Always ignore bytes [4..] if they exist in the file.
613 *
614 * Only the first four bytes are significant, even on systems that
615 * have a 64-bit word size.
616 *
617 * See:
618 *
619 * eglibc: sysdeps/unix/sysv/linux/gethostid.c
620 * coreutils: src/hostid.c
621 *
622 * Notes:
623 *
624 * The /etc/hostid file on Solaris is a text file that often reads:
625 *
626 * # DO NOT EDIT
627 * "0123456789"
628 *
629 * Directly copying this file to Linux results in a constant
630 * hostid of 4f442023 because the default comment constitutes
631 * the first four bytes of the file.
632 *
633 */
634
635 char *spl_hostid_path = HW_HOSTID_PATH;
636 module_param(spl_hostid_path, charp, 0444);
637 MODULE_PARM_DESC(spl_hostid_path, "The system hostid file (/etc/hostid)");
638
639 static int
hostid_read(uint32_t * hostid)640 hostid_read(uint32_t *hostid)
641 {
642 uint64_t size;
643 uint32_t value = 0;
644 int error;
645 loff_t off;
646 struct file *filp;
647 struct kstat stat;
648
649 filp = filp_open(spl_hostid_path, 0, 0);
650
651 if (IS_ERR(filp))
652 return (ENOENT);
653
654 error = spl_getattr(filp, &stat);
655 if (error) {
656 filp_close(filp, 0);
657 return (error);
658 }
659 size = stat.size;
660 if (size < sizeof (HW_HOSTID_MASK)) {
661 filp_close(filp, 0);
662 return (EINVAL);
663 }
664
665 off = 0;
666 /*
667 * Read directly into the variable like eglibc does.
668 * Short reads are okay; native behavior is preserved.
669 */
670 error = spl_kernel_read(filp, &value, sizeof (value), &off);
671 if (error < 0) {
672 filp_close(filp, 0);
673 return (EIO);
674 }
675
676 /* Mask down to 32 bits like coreutils does. */
677 *hostid = (value & HW_HOSTID_MASK);
678 filp_close(filp, 0);
679
680 return (0);
681 }
682
683 /*
684 * Return the system hostid. Preferentially use the spl_hostid module option
685 * when set, otherwise use the value in the /etc/hostid file.
686 */
687 uint32_t
zone_get_hostid(void * zone)688 zone_get_hostid(void *zone)
689 {
690 uint32_t hostid;
691
692 ASSERT3P(zone, ==, NULL);
693
694 if (spl_hostid != 0)
695 return ((uint32_t)(spl_hostid & HW_HOSTID_MASK));
696
697 if (hostid_read(&hostid) == 0)
698 return (hostid);
699
700 return (0);
701 }
702 EXPORT_SYMBOL(zone_get_hostid);
703
704 static int
spl_kvmem_init(void)705 spl_kvmem_init(void)
706 {
707 int rc = 0;
708
709 rc = spl_kmem_init();
710 if (rc)
711 return (rc);
712
713 rc = spl_vmem_init();
714 if (rc) {
715 spl_kmem_fini();
716 return (rc);
717 }
718
719 return (rc);
720 }
721
722 /*
723 * We initialize the random number generator with 128 bits of entropy from the
724 * system random number generator. In the improbable case that we have a zero
725 * seed, we fallback to the system jiffies, unless it is also zero, in which
726 * situation we use a preprogrammed seed. We step forward by 2^64 iterations to
727 * initialize each of the per-cpu seeds so that the sequences generated on each
728 * CPU are guaranteed to never overlap in practice.
729 */
730 static void __init
spl_random_init(void)731 spl_random_init(void)
732 {
733 uint64_t s[2];
734 int i = 0;
735
736 spl_pseudo_entropy = __alloc_percpu(2 * sizeof (uint64_t),
737 sizeof (uint64_t));
738
739 get_random_bytes(s, sizeof (s));
740
741 if (s[0] == 0 && s[1] == 0) {
742 if (jiffies != 0) {
743 s[0] = jiffies;
744 s[1] = ~0 - jiffies;
745 } else {
746 (void) memcpy(s, "improbable seed", sizeof (s));
747 }
748 printk("SPL: get_random_bytes() returned 0 "
749 "when generating random seed. Setting initial seed to "
750 "0x%016llx%016llx.\n", cpu_to_be64(s[0]),
751 cpu_to_be64(s[1]));
752 }
753
754 for_each_possible_cpu(i) {
755 uint64_t *wordp = per_cpu_ptr(spl_pseudo_entropy, i);
756
757 spl_rand_jump(s);
758
759 wordp[0] = s[0];
760 wordp[1] = s[1];
761 }
762 }
763
764 static void
spl_random_fini(void)765 spl_random_fini(void)
766 {
767 free_percpu(spl_pseudo_entropy);
768 }
769
770 static void
spl_kvmem_fini(void)771 spl_kvmem_fini(void)
772 {
773 spl_vmem_fini();
774 spl_kmem_fini();
775 }
776
777 static int __init
spl_init(void)778 spl_init(void)
779 {
780 int rc = 0;
781
782 bzero(&p0, sizeof (proc_t));
783 spl_random_init();
784
785 if ((rc = spl_kvmem_init()))
786 goto out1;
787
788 if ((rc = spl_tsd_init()))
789 goto out2;
790
791 if ((rc = spl_taskq_init()))
792 goto out3;
793
794 if ((rc = spl_kmem_cache_init()))
795 goto out4;
796
797 if ((rc = spl_proc_init()))
798 goto out5;
799
800 if ((rc = spl_kstat_init()))
801 goto out6;
802
803 if ((rc = spl_zlib_init()))
804 goto out7;
805
806 return (rc);
807
808 out7:
809 spl_kstat_fini();
810 out6:
811 spl_proc_fini();
812 out5:
813 spl_kmem_cache_fini();
814 out4:
815 spl_taskq_fini();
816 out3:
817 spl_tsd_fini();
818 out2:
819 spl_kvmem_fini();
820 out1:
821 return (rc);
822 }
823
824 static void __exit
spl_fini(void)825 spl_fini(void)
826 {
827 spl_zlib_fini();
828 spl_kstat_fini();
829 spl_proc_fini();
830 spl_kmem_cache_fini();
831 spl_taskq_fini();
832 spl_tsd_fini();
833 spl_kvmem_fini();
834 spl_random_fini();
835 }
836
837 module_init(spl_init);
838 module_exit(spl_fini);
839
840 ZFS_MODULE_DESCRIPTION("Solaris Porting Layer");
841 ZFS_MODULE_AUTHOR(ZFS_META_AUTHOR);
842 ZFS_MODULE_LICENSE("GPL");
843 ZFS_MODULE_VERSION(ZFS_META_VERSION "-" ZFS_META_RELEASE);
844