1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright (c) 2012 by Delphix. All rights reserved.
24 */
25
26 #include <assert.h>
27 #include <fcntl.h>
28 #include <poll.h>
29 #include <stdio.h>
30 #include <stdlib.h>
31 #include <string.h>
32 #include <zlib.h>
33 #include <sys/spa.h>
34 #include <sys/stat.h>
35 #include <sys/processor.h>
36 #include <sys/zfs_context.h>
37 #include <sys/zmod.h>
38 #include <sys/utsname.h>
39 #include <sys/systeminfo.h>
40
41 /*
42 * Emulation of kernel services in userland.
43 */
44
45 int aok;
46 uint64_t physmem;
47 vnode_t *rootdir = (vnode_t *)0xabcd1234;
48 char hw_serial[HW_HOSTID_LEN];
49 vmem_t *zio_arena = NULL;
50
51 struct utsname utsname = {
52 "userland", "libzpool", "1", "1", "na"
53 };
54
55 /* this only exists to have its address taken */
56 struct proc p0;
57
58 /*
59 * =========================================================================
60 * threads
61 * =========================================================================
62 */
63 /*ARGSUSED*/
64 kthread_t *
65 zk_thread_create(void (*func)(), void *arg)
66 {
67 thread_t tid;
68
69 VERIFY(thr_create(0, 0, (void *(*)(void *))func, arg, THR_DETACHED,
70 &tid) == 0);
71
72 return ((void *)(uintptr_t)tid);
73 }
74
75 /*
76 * =========================================================================
77 * kstats
78 * =========================================================================
79 */
80 /*ARGSUSED*/
81 kstat_t *
82 kstat_create(char *module, int instance, char *name, char *class,
83 uchar_t type, ulong_t ndata, uchar_t ks_flag)
84 {
85 return (NULL);
86 }
87
88 /*ARGSUSED*/
89 void
90 kstat_install(kstat_t *ksp)
91 {}
92
93 /*ARGSUSED*/
94 void
95 kstat_delete(kstat_t *ksp)
96 {}
97
98 /*
99 * =========================================================================
100 * mutexes
101 * =========================================================================
102 */
103 void
104 zmutex_init(kmutex_t *mp)
105 {
106 mp->m_owner = NULL;
107 mp->initialized = B_TRUE;
108 (void) _mutex_init(&mp->m_lock, USYNC_THREAD, NULL);
109 }
110
111 void
112 zmutex_destroy(kmutex_t *mp)
113 {
114 ASSERT(mp->initialized == B_TRUE);
115 ASSERT(mp->m_owner == NULL);
116 (void) _mutex_destroy(&(mp)->m_lock);
117 mp->m_owner = (void *)-1UL;
118 mp->initialized = B_FALSE;
119 }
120
121 void
122 mutex_enter(kmutex_t *mp)
123 {
124 ASSERT(mp->initialized == B_TRUE);
125 ASSERT(mp->m_owner != (void *)-1UL);
126 ASSERT(mp->m_owner != curthread);
127 VERIFY(mutex_lock(&mp->m_lock) == 0);
128 ASSERT(mp->m_owner == NULL);
129 mp->m_owner = curthread;
130 }
131
132 int
133 mutex_tryenter(kmutex_t *mp)
134 {
135 ASSERT(mp->initialized == B_TRUE);
136 ASSERT(mp->m_owner != (void *)-1UL);
137 if (0 == mutex_trylock(&mp->m_lock)) {
138 ASSERT(mp->m_owner == NULL);
139 mp->m_owner = curthread;
140 return (1);
141 } else {
142 return (0);
143 }
144 }
145
146 void
147 mutex_exit(kmutex_t *mp)
148 {
149 ASSERT(mp->initialized == B_TRUE);
150 ASSERT(mutex_owner(mp) == curthread);
151 mp->m_owner = NULL;
152 VERIFY(mutex_unlock(&mp->m_lock) == 0);
153 }
154
155 void *
156 mutex_owner(kmutex_t *mp)
157 {
158 ASSERT(mp->initialized == B_TRUE);
159 return (mp->m_owner);
160 }
161
162 /*
163 * =========================================================================
164 * rwlocks
165 * =========================================================================
166 */
167 /*ARGSUSED*/
168 void
169 rw_init(krwlock_t *rwlp, char *name, int type, void *arg)
170 {
171 rwlock_init(&rwlp->rw_lock, USYNC_THREAD, NULL);
172 rwlp->rw_owner = NULL;
173 rwlp->initialized = B_TRUE;
174 }
175
176 void
177 rw_destroy(krwlock_t *rwlp)
178 {
179 rwlock_destroy(&rwlp->rw_lock);
180 rwlp->rw_owner = (void *)-1UL;
181 rwlp->initialized = B_FALSE;
182 }
183
184 void
185 rw_enter(krwlock_t *rwlp, krw_t rw)
186 {
187 ASSERT(!RW_LOCK_HELD(rwlp));
188 ASSERT(rwlp->initialized == B_TRUE);
189 ASSERT(rwlp->rw_owner != (void *)-1UL);
190 ASSERT(rwlp->rw_owner != curthread);
191
192 if (rw == RW_READER)
193 VERIFY(rw_rdlock(&rwlp->rw_lock) == 0);
194 else
195 VERIFY(rw_wrlock(&rwlp->rw_lock) == 0);
196
197 rwlp->rw_owner = curthread;
198 }
199
200 void
201 rw_exit(krwlock_t *rwlp)
202 {
203 ASSERT(rwlp->initialized == B_TRUE);
204 ASSERT(rwlp->rw_owner != (void *)-1UL);
205
206 rwlp->rw_owner = NULL;
207 VERIFY(rw_unlock(&rwlp->rw_lock) == 0);
208 }
209
210 int
211 rw_tryenter(krwlock_t *rwlp, krw_t rw)
212 {
213 int rv;
214
215 ASSERT(rwlp->initialized == B_TRUE);
216 ASSERT(rwlp->rw_owner != (void *)-1UL);
217
218 if (rw == RW_READER)
219 rv = rw_tryrdlock(&rwlp->rw_lock);
220 else
221 rv = rw_trywrlock(&rwlp->rw_lock);
222
223 if (rv == 0) {
224 rwlp->rw_owner = curthread;
225 return (1);
226 }
227
228 return (0);
229 }
230
231 /*ARGSUSED*/
232 int
233 rw_tryupgrade(krwlock_t *rwlp)
234 {
235 ASSERT(rwlp->initialized == B_TRUE);
236 ASSERT(rwlp->rw_owner != (void *)-1UL);
237
238 return (0);
239 }
240
241 /*
242 * =========================================================================
243 * condition variables
244 * =========================================================================
245 */
246 /*ARGSUSED*/
247 void
248 cv_init(kcondvar_t *cv, char *name, int type, void *arg)
249 {
250 VERIFY(cond_init(cv, type, NULL) == 0);
251 }
252
253 void
254 cv_destroy(kcondvar_t *cv)
255 {
256 VERIFY(cond_destroy(cv) == 0);
257 }
258
259 void
260 cv_wait(kcondvar_t *cv, kmutex_t *mp)
261 {
262 ASSERT(mutex_owner(mp) == curthread);
263 mp->m_owner = NULL;
264 int ret = cond_wait(cv, &mp->m_lock);
265 VERIFY(ret == 0 || ret == EINTR);
266 mp->m_owner = curthread;
267 }
268
269 clock_t
270 cv_timedwait(kcondvar_t *cv, kmutex_t *mp, clock_t abstime)
271 {
272 int error;
273 timestruc_t ts;
274 clock_t delta;
275
276 top:
277 delta = abstime - ddi_get_lbolt();
278 if (delta <= 0)
279 return (-1);
280
281 ts.tv_sec = delta / hz;
282 ts.tv_nsec = (delta % hz) * (NANOSEC / hz);
283
284 ASSERT(mutex_owner(mp) == curthread);
285 mp->m_owner = NULL;
286 error = cond_reltimedwait(cv, &mp->m_lock, &ts);
287 mp->m_owner = curthread;
288
289 if (error == ETIME)
290 return (-1);
291
292 if (error == EINTR)
293 goto top;
294
295 ASSERT(error == 0);
296
297 return (1);
298 }
299
300 void
301 cv_signal(kcondvar_t *cv)
302 {
303 VERIFY(cond_signal(cv) == 0);
304 }
305
306 void
307 cv_broadcast(kcondvar_t *cv)
308 {
309 VERIFY(cond_broadcast(cv) == 0);
310 }
311
312 /*
313 * =========================================================================
314 * vnode operations
315 * =========================================================================
316 */
317 /*
318 * Note: for the xxxat() versions of these functions, we assume that the
319 * starting vp is always rootdir (which is true for spa_directory.c, the only
320 * ZFS consumer of these interfaces). We assert this is true, and then emulate
321 * them by adding '/' in front of the path.
322 */
323
324 /*ARGSUSED*/
325 int
326 vn_open(char *path, int x1, int flags, int mode, vnode_t **vpp, int x2, int x3)
327 {
328 int fd;
329 vnode_t *vp;
330 int old_umask;
331 char realpath[MAXPATHLEN];
332 struct stat64 st;
333
334 /*
335 * If we're accessing a real disk from userland, we need to use
336 * the character interface to avoid caching. This is particularly
337 * important if we're trying to look at a real in-kernel storage
338 * pool from userland, e.g. via zdb, because otherwise we won't
339 * see the changes occurring under the segmap cache.
340 * On the other hand, the stupid character device returns zero
341 * for its size. So -- gag -- we open the block device to get
342 * its size, and remember it for subsequent VOP_GETATTR().
343 */
344 if (strncmp(path, "/dev/", 5) == 0) {
345 char *dsk;
346 fd = open64(path, O_RDONLY);
347 if (fd == -1)
348 return (errno);
349 if (fstat64(fd, &st) == -1) {
350 close(fd);
351 return (errno);
352 }
353 close(fd);
354 (void) sprintf(realpath, "%s", path);
355 dsk = strstr(path, "/dsk/");
356 if (dsk != NULL)
357 (void) sprintf(realpath + (dsk - path) + 1, "r%s",
358 dsk + 1);
359 } else {
360 (void) sprintf(realpath, "%s", path);
361 if (!(flags & FCREAT) && stat64(realpath, &st) == -1)
362 return (errno);
363 }
364
365 if (flags & FCREAT)
366 old_umask = umask(0);
367
368 /*
369 * The construct 'flags - FREAD' conveniently maps combinations of
370 * FREAD and FWRITE to the corresponding O_RDONLY, O_WRONLY, and O_RDWR.
371 */
372 fd = open64(realpath, flags - FREAD, mode);
373
374 if (flags & FCREAT)
375 (void) umask(old_umask);
376
377 if (fd == -1)
378 return (errno);
379
380 if (fstat64(fd, &st) == -1) {
381 close(fd);
382 return (errno);
383 }
384
385 (void) fcntl(fd, F_SETFD, FD_CLOEXEC);
386
387 *vpp = vp = umem_zalloc(sizeof (vnode_t), UMEM_NOFAIL);
388
389 vp->v_fd = fd;
390 vp->v_size = st.st_size;
391 vp->v_path = spa_strdup(path);
392
393 return (0);
394 }
395
396 /*ARGSUSED*/
397 int
398 vn_openat(char *path, int x1, int flags, int mode, vnode_t **vpp, int x2,
399 int x3, vnode_t *startvp, int fd)
400 {
401 char *realpath = umem_alloc(strlen(path) + 2, UMEM_NOFAIL);
402 int ret;
403
404 ASSERT(startvp == rootdir);
405 (void) sprintf(realpath, "/%s", path);
406
407 /* fd ignored for now, need if want to simulate nbmand support */
408 ret = vn_open(realpath, x1, flags, mode, vpp, x2, x3);
409
410 umem_free(realpath, strlen(path) + 2);
411
412 return (ret);
413 }
414
415 /*ARGSUSED*/
416 int
417 vn_rdwr(int uio, vnode_t *vp, void *addr, ssize_t len, offset_t offset,
418 int x1, int x2, rlim64_t x3, void *x4, ssize_t *residp)
419 {
420 ssize_t iolen, split;
421
422 if (uio == UIO_READ) {
423 iolen = pread64(vp->v_fd, addr, len, offset);
424 } else {
425 /*
426 * To simulate partial disk writes, we split writes into two
427 * system calls so that the process can be killed in between.
428 */
429 int sectors = len >> SPA_MINBLOCKSHIFT;
430 split = (sectors > 0 ? rand() % sectors : 0) <<
431 SPA_MINBLOCKSHIFT;
432 iolen = pwrite64(vp->v_fd, addr, split, offset);
433 iolen += pwrite64(vp->v_fd, (char *)addr + split,
434 len - split, offset + split);
435 }
436
437 if (iolen == -1)
438 return (errno);
439 if (residp)
440 *residp = len - iolen;
441 else if (iolen != len)
442 return (EIO);
443 return (0);
444 }
445
446 void
447 vn_close(vnode_t *vp)
448 {
449 close(vp->v_fd);
450 spa_strfree(vp->v_path);
451 umem_free(vp, sizeof (vnode_t));
452 }
453
454 /*
455 * At a minimum we need to update the size since vdev_reopen()
456 * will no longer call vn_openat().
457 */
458 int
459 fop_getattr(vnode_t *vp, vattr_t *vap)
460 {
461 struct stat64 st;
462
463 if (fstat64(vp->v_fd, &st) == -1) {
464 close(vp->v_fd);
465 return (errno);
466 }
467
468 vap->va_size = st.st_size;
469 return (0);
470 }
471
472 #ifdef ZFS_DEBUG
473
474 /*
475 * =========================================================================
476 * Figure out which debugging statements to print
477 * =========================================================================
478 */
479
480 static char *dprintf_string;
481 static int dprintf_print_all;
482
483 int
484 dprintf_find_string(const char *string)
485 {
486 char *tmp_str = dprintf_string;
487 int len = strlen(string);
488
489 /*
490 * Find out if this is a string we want to print.
491 * String format: file1.c,function_name1,file2.c,file3.c
492 */
493
494 while (tmp_str != NULL) {
495 if (strncmp(tmp_str, string, len) == 0 &&
496 (tmp_str[len] == ',' || tmp_str[len] == '\0'))
497 return (1);
498 tmp_str = strchr(tmp_str, ',');
499 if (tmp_str != NULL)
500 tmp_str++; /* Get rid of , */
501 }
502 return (0);
503 }
504
505 void
506 dprintf_setup(int *argc, char **argv)
507 {
508 int i, j;
509
510 /*
511 * Debugging can be specified two ways: by setting the
512 * environment variable ZFS_DEBUG, or by including a
513 * "debug=..." argument on the command line. The command
514 * line setting overrides the environment variable.
515 */
516
517 for (i = 1; i < *argc; i++) {
518 int len = strlen("debug=");
519 /* First look for a command line argument */
520 if (strncmp("debug=", argv[i], len) == 0) {
521 dprintf_string = argv[i] + len;
522 /* Remove from args */
523 for (j = i; j < *argc; j++)
524 argv[j] = argv[j+1];
525 argv[j] = NULL;
526 (*argc)--;
527 }
528 }
529
530 if (dprintf_string == NULL) {
531 /* Look for ZFS_DEBUG environment variable */
532 dprintf_string = getenv("ZFS_DEBUG");
533 }
534
535 /*
536 * Are we just turning on all debugging?
537 */
538 if (dprintf_find_string("on"))
539 dprintf_print_all = 1;
540 }
541
542 /*
543 * =========================================================================
544 * debug printfs
545 * =========================================================================
546 */
547 void
548 __dprintf(const char *file, const char *func, int line, const char *fmt, ...)
549 {
550 const char *newfile;
551 va_list adx;
552
553 /*
554 * Get rid of annoying "../common/" prefix to filename.
555 */
556 newfile = strrchr(file, '/');
557 if (newfile != NULL) {
558 newfile = newfile + 1; /* Get rid of leading / */
559 } else {
560 newfile = file;
561 }
562
563 if (dprintf_print_all ||
564 dprintf_find_string(newfile) ||
565 dprintf_find_string(func)) {
566 /* Print out just the function name if requested */
567 flockfile(stdout);
568 if (dprintf_find_string("pid"))
569 (void) printf("%d ", getpid());
570 if (dprintf_find_string("tid"))
571 (void) printf("%u ", thr_self());
572 if (dprintf_find_string("cpu"))
573 (void) printf("%u ", getcpuid());
574 if (dprintf_find_string("time"))
575 (void) printf("%llu ", gethrtime());
576 if (dprintf_find_string("long"))
577 (void) printf("%s, line %d: ", newfile, line);
578 (void) printf("%s: ", func);
579 va_start(adx, fmt);
580 (void) vprintf(fmt, adx);
581 va_end(adx);
582 funlockfile(stdout);
583 }
584 }
585
586 #endif /* ZFS_DEBUG */
587
588 /*
589 * =========================================================================
590 * cmn_err() and panic()
591 * =========================================================================
592 */
593 static char ce_prefix[CE_IGNORE][10] = { "", "NOTICE: ", "WARNING: ", "" };
594 static char ce_suffix[CE_IGNORE][2] = { "", "\n", "\n", "" };
595
596 void
597 vpanic(const char *fmt, va_list adx)
598 {
599 (void) fprintf(stderr, "error: ");
600 (void) vfprintf(stderr, fmt, adx);
601 (void) fprintf(stderr, "\n");
602
603 abort(); /* think of it as a "user-level crash dump" */
604 }
605
606 void
607 panic(const char *fmt, ...)
608 {
609 va_list adx;
610
611 va_start(adx, fmt);
612 vpanic(fmt, adx);
613 va_end(adx);
614 }
615
616 void
617 vcmn_err(int ce, const char *fmt, va_list adx)
618 {
619 if (ce == CE_PANIC)
620 vpanic(fmt, adx);
621 if (ce != CE_NOTE) { /* suppress noise in userland stress testing */
622 (void) fprintf(stderr, "%s", ce_prefix[ce]);
623 (void) vfprintf(stderr, fmt, adx);
624 (void) fprintf(stderr, "%s", ce_suffix[ce]);
625 }
626 }
627
628 /*PRINTFLIKE2*/
629 void
630 cmn_err(int ce, const char *fmt, ...)
631 {
632 va_list adx;
633
634 va_start(adx, fmt);
635 vcmn_err(ce, fmt, adx);
636 va_end(adx);
637 }
638
639 /*
640 * =========================================================================
641 * kobj interfaces
642 * =========================================================================
643 */
644 struct _buf *
645 kobj_open_file(char *name)
646 {
647 struct _buf *file;
648 vnode_t *vp;
649
650 /* set vp as the _fd field of the file */
651 if (vn_openat(name, UIO_SYSSPACE, FREAD, 0, &vp, 0, 0, rootdir,
652 -1) != 0)
653 return ((void *)-1UL);
654
655 file = umem_zalloc(sizeof (struct _buf), UMEM_NOFAIL);
656 file->_fd = (intptr_t)vp;
657 return (file);
658 }
659
660 int
661 kobj_read_file(struct _buf *file, char *buf, unsigned size, unsigned off)
662 {
663 ssize_t resid;
664
665 vn_rdwr(UIO_READ, (vnode_t *)file->_fd, buf, size, (offset_t)off,
666 UIO_SYSSPACE, 0, 0, 0, &resid);
667
668 return (size - resid);
669 }
670
671 void
672 kobj_close_file(struct _buf *file)
673 {
674 vn_close((vnode_t *)file->_fd);
675 umem_free(file, sizeof (struct _buf));
676 }
677
678 int
679 kobj_get_filesize(struct _buf *file, uint64_t *size)
680 {
681 struct stat64 st;
682 vnode_t *vp = (vnode_t *)file->_fd;
683
684 if (fstat64(vp->v_fd, &st) == -1) {
685 vn_close(vp);
686 return (errno);
687 }
688 *size = st.st_size;
689 return (0);
690 }
691
692 /*
693 * =========================================================================
694 * misc routines
695 * =========================================================================
696 */
697
698 void
699 delay(clock_t ticks)
700 {
701 poll(0, 0, ticks * (1000 / hz));
702 }
703
704 /*
705 * Find highest one bit set.
706 * Returns bit number + 1 of highest bit that is set, otherwise returns 0.
707 * High order bit is 31 (or 63 in _LP64 kernel).
708 */
709 int
710 highbit(ulong_t i)
711 {
712 register int h = 1;
713
714 if (i == 0)
715 return (0);
716 #ifdef _LP64
717 if (i & 0xffffffff00000000ul) {
718 h += 32; i >>= 32;
719 }
720 #endif
721 if (i & 0xffff0000) {
722 h += 16; i >>= 16;
723 }
724 if (i & 0xff00) {
725 h += 8; i >>= 8;
726 }
727 if (i & 0xf0) {
728 h += 4; i >>= 4;
729 }
730 if (i & 0xc) {
731 h += 2; i >>= 2;
732 }
733 if (i & 0x2) {
734 h += 1;
735 }
736 return (h);
737 }
738
739 static int random_fd = -1, urandom_fd = -1;
740
741 static int
742 random_get_bytes_common(uint8_t *ptr, size_t len, int fd)
743 {
744 size_t resid = len;
745 ssize_t bytes;
746
747 ASSERT(fd != -1);
748
749 while (resid != 0) {
750 bytes = read(fd, ptr, resid);
751 ASSERT3S(bytes, >=, 0);
752 ptr += bytes;
753 resid -= bytes;
754 }
755
756 return (0);
757 }
758
759 int
760 random_get_bytes(uint8_t *ptr, size_t len)
761 {
762 return (random_get_bytes_common(ptr, len, random_fd));
763 }
764
765 int
766 random_get_pseudo_bytes(uint8_t *ptr, size_t len)
767 {
768 return (random_get_bytes_common(ptr, len, urandom_fd));
769 }
770
771 int
772 ddi_strtoul(const char *hw_serial, char **nptr, int base, unsigned long *result)
773 {
774 char *end;
775
776 *result = strtoul(hw_serial, &end, base);
777 if (*result == 0)
778 return (errno);
779 return (0);
780 }
781
782 int
783 ddi_strtoull(const char *str, char **nptr, int base, u_longlong_t *result)
784 {
785 char *end;
786
787 *result = strtoull(str, &end, base);
788 if (*result == 0)
789 return (errno);
790 return (0);
791 }
792
793 /*
794 * =========================================================================
795 * kernel emulation setup & teardown
796 * =========================================================================
797 */
798 static int
799 umem_out_of_memory(void)
800 {
801 char errmsg[] = "out of memory -- generating core dump\n";
802
803 write(fileno(stderr), errmsg, sizeof (errmsg));
804 abort();
805 return (0);
806 }
807
808 void
809 kernel_init(int mode)
810 {
811 umem_nofail_callback(umem_out_of_memory);
812
813 physmem = sysconf(_SC_PHYS_PAGES);
814
815 dprintf("physmem = %llu pages (%.2f GB)\n", physmem,
816 (double)physmem * sysconf(_SC_PAGE_SIZE) / (1ULL << 30));
817
818 (void) snprintf(hw_serial, sizeof (hw_serial), "%ld",
819 (mode & FWRITE) ? gethostid() : 0);
820
821 VERIFY((random_fd = open("/dev/random", O_RDONLY)) != -1);
822 VERIFY((urandom_fd = open("/dev/urandom", O_RDONLY)) != -1);
823
824 system_taskq_init();
825
826 spa_init(mode);
827 }
828
829 void
830 kernel_fini(void)
831 {
832 spa_fini();
833
834 system_taskq_fini();
835
836 close(random_fd);
837 close(urandom_fd);
838
839 random_fd = -1;
840 urandom_fd = -1;
841 }
842
843 int
844 z_uncompress(void *dst, size_t *dstlen, const void *src, size_t srclen)
845 {
846 int ret;
847 uLongf len = *dstlen;
848
849 if ((ret = uncompress(dst, &len, src, srclen)) == Z_OK)
850 *dstlen = (size_t)len;
851
852 return (ret);
853 }
854
855 int
856 z_compress_level(void *dst, size_t *dstlen, const void *src, size_t srclen,
857 int level)
858 {
859 int ret;
860 uLongf len = *dstlen;
861
862 if ((ret = compress2(dst, &len, src, srclen, level)) == Z_OK)
863 *dstlen = (size_t)len;
864
865 return (ret);
866 }
867
868 uid_t
869 crgetuid(cred_t *cr)
870 {
871 return (0);
872 }
873
874 gid_t
875 crgetgid(cred_t *cr)
876 {
877 return (0);
878 }
879
880 int
881 crgetngroups(cred_t *cr)
882 {
883 return (0);
884 }
885
886 gid_t *
887 crgetgroups(cred_t *cr)
888 {
889 return (NULL);
890 }
891
892 int
893 zfs_secpolicy_snapshot_perms(const char *name, cred_t *cr)
894 {
895 return (0);
896 }
897
898 int
899 zfs_secpolicy_rename_perms(const char *from, const char *to, cred_t *cr)
900 {
901 return (0);
902 }
903
904 int
905 zfs_secpolicy_destroy_perms(const char *name, cred_t *cr)
906 {
907 return (0);
908 }
909
910 ksiddomain_t *
911 ksid_lookupdomain(const char *dom)
912 {
913 ksiddomain_t *kd;
914
915 kd = umem_zalloc(sizeof (ksiddomain_t), UMEM_NOFAIL);
916 kd->kd_name = spa_strdup(dom);
917 return (kd);
918 }
919
920 void
921 ksiddomain_rele(ksiddomain_t *ksid)
922 {
923 spa_strfree(ksid->kd_name);
924 umem_free(ksid, sizeof (ksiddomain_t));
925 }
926
927 /*
928 * Do not change the length of the returned string; it must be freed
929 * with strfree().
930 */
931 char *
932 kmem_asprintf(const char *fmt, ...)
933 {
934 int size;
935 va_list adx;
936 char *buf;
937
938 va_start(adx, fmt);
939 size = vsnprintf(NULL, 0, fmt, adx) + 1;
940 va_end(adx);
941
942 buf = kmem_alloc(size, KM_SLEEP);
943
944 va_start(adx, fmt);
945 size = vsnprintf(buf, size, fmt, adx);
946 va_end(adx);
947
948 return (buf);
949 }
950
951 /* ARGSUSED */
952 int
953 zfs_onexit_fd_hold(int fd, minor_t *minorp)
954 {
955 *minorp = 0;
956 return (0);
957 }
958
959 /* ARGSUSED */
960 void
961 zfs_onexit_fd_rele(int fd)
962 {
963 }
964
965 /* ARGSUSED */
966 int
967 zfs_onexit_add_cb(minor_t minor, void (*func)(void *), void *data,
968 uint64_t *action_handle)
969 {
970 return (0);
971 }
972
973 /* ARGSUSED */
974 int
975 zfs_onexit_del_cb(minor_t minor, uint64_t action_handle, boolean_t fire)
976 {
977 return (0);
978 }
979
980 /* ARGSUSED */
981 int
982 zfs_onexit_cb_data(minor_t minor, uint64_t action_handle, void **data)
983 {
984 return (0);
985 }