xref: /titanic_52/usr/src/lib/libzpool/common/kernel.c (revision 25345e466695fbe736faa53b8f3413d8e8f81981)
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 kmutex_t cpu_lock;
50 vmem_t *zio_arena = NULL;
51 
52 struct utsname utsname = {
53 	"userland", "libzpool", "1", "1", "na"
54 };
55 
56 /* this only exists to have its address taken */
57 struct proc p0;
58 
59 /*
60  * =========================================================================
61  * threads
62  * =========================================================================
63  */
64 /*ARGSUSED*/
65 kthread_t *
66 zk_thread_create(void (*func)(), void *arg)
67 {
68 	thread_t tid;
69 
70 	VERIFY(thr_create(0, 0, (void *(*)(void *))func, arg, THR_DETACHED,
71 	    &tid) == 0);
72 
73 	return ((void *)(uintptr_t)tid);
74 }
75 
76 /*
77  * =========================================================================
78  * kstats
79  * =========================================================================
80  */
81 /*ARGSUSED*/
82 kstat_t *
83 kstat_create(char *module, int instance, char *name, char *class,
84     uchar_t type, ulong_t ndata, uchar_t ks_flag)
85 {
86 	return (NULL);
87 }
88 
89 /*ARGSUSED*/
90 void
91 kstat_install(kstat_t *ksp)
92 {}
93 
94 /*ARGSUSED*/
95 void
96 kstat_delete(kstat_t *ksp)
97 {}
98 
99 /*
100  * =========================================================================
101  * mutexes
102  * =========================================================================
103  */
104 void
105 zmutex_init(kmutex_t *mp)
106 {
107 	mp->m_owner = NULL;
108 	mp->initialized = B_TRUE;
109 	(void) _mutex_init(&mp->m_lock, USYNC_THREAD, NULL);
110 }
111 
112 void
113 zmutex_destroy(kmutex_t *mp)
114 {
115 	ASSERT(mp->initialized == B_TRUE);
116 	ASSERT(mp->m_owner == NULL);
117 	(void) _mutex_destroy(&(mp)->m_lock);
118 	mp->m_owner = (void *)-1UL;
119 	mp->initialized = B_FALSE;
120 }
121 
122 void
123 mutex_enter(kmutex_t *mp)
124 {
125 	ASSERT(mp->initialized == B_TRUE);
126 	ASSERT(mp->m_owner != (void *)-1UL);
127 	ASSERT(mp->m_owner != curthread);
128 	VERIFY(mutex_lock(&mp->m_lock) == 0);
129 	ASSERT(mp->m_owner == NULL);
130 	mp->m_owner = curthread;
131 }
132 
133 int
134 mutex_tryenter(kmutex_t *mp)
135 {
136 	ASSERT(mp->initialized == B_TRUE);
137 	ASSERT(mp->m_owner != (void *)-1UL);
138 	if (0 == mutex_trylock(&mp->m_lock)) {
139 		ASSERT(mp->m_owner == NULL);
140 		mp->m_owner = curthread;
141 		return (1);
142 	} else {
143 		return (0);
144 	}
145 }
146 
147 void
148 mutex_exit(kmutex_t *mp)
149 {
150 	ASSERT(mp->initialized == B_TRUE);
151 	ASSERT(mutex_owner(mp) == curthread);
152 	mp->m_owner = NULL;
153 	VERIFY(mutex_unlock(&mp->m_lock) == 0);
154 }
155 
156 void *
157 mutex_owner(kmutex_t *mp)
158 {
159 	ASSERT(mp->initialized == B_TRUE);
160 	return (mp->m_owner);
161 }
162 
163 /*
164  * =========================================================================
165  * rwlocks
166  * =========================================================================
167  */
168 /*ARGSUSED*/
169 void
170 rw_init(krwlock_t *rwlp, char *name, int type, void *arg)
171 {
172 	rwlock_init(&rwlp->rw_lock, USYNC_THREAD, NULL);
173 	rwlp->rw_owner = NULL;
174 	rwlp->initialized = B_TRUE;
175 }
176 
177 void
178 rw_destroy(krwlock_t *rwlp)
179 {
180 	rwlock_destroy(&rwlp->rw_lock);
181 	rwlp->rw_owner = (void *)-1UL;
182 	rwlp->initialized = B_FALSE;
183 }
184 
185 void
186 rw_enter(krwlock_t *rwlp, krw_t rw)
187 {
188 	ASSERT(!RW_LOCK_HELD(rwlp));
189 	ASSERT(rwlp->initialized == B_TRUE);
190 	ASSERT(rwlp->rw_owner != (void *)-1UL);
191 	ASSERT(rwlp->rw_owner != curthread);
192 
193 	if (rw == RW_READER)
194 		VERIFY(rw_rdlock(&rwlp->rw_lock) == 0);
195 	else
196 		VERIFY(rw_wrlock(&rwlp->rw_lock) == 0);
197 
198 	rwlp->rw_owner = curthread;
199 }
200 
201 void
202 rw_exit(krwlock_t *rwlp)
203 {
204 	ASSERT(rwlp->initialized == B_TRUE);
205 	ASSERT(rwlp->rw_owner != (void *)-1UL);
206 
207 	rwlp->rw_owner = NULL;
208 	VERIFY(rw_unlock(&rwlp->rw_lock) == 0);
209 }
210 
211 int
212 rw_tryenter(krwlock_t *rwlp, krw_t rw)
213 {
214 	int rv;
215 
216 	ASSERT(rwlp->initialized == B_TRUE);
217 	ASSERT(rwlp->rw_owner != (void *)-1UL);
218 
219 	if (rw == RW_READER)
220 		rv = rw_tryrdlock(&rwlp->rw_lock);
221 	else
222 		rv = rw_trywrlock(&rwlp->rw_lock);
223 
224 	if (rv == 0) {
225 		rwlp->rw_owner = curthread;
226 		return (1);
227 	}
228 
229 	return (0);
230 }
231 
232 /*ARGSUSED*/
233 int
234 rw_tryupgrade(krwlock_t *rwlp)
235 {
236 	ASSERT(rwlp->initialized == B_TRUE);
237 	ASSERT(rwlp->rw_owner != (void *)-1UL);
238 
239 	return (0);
240 }
241 
242 /*
243  * =========================================================================
244  * condition variables
245  * =========================================================================
246  */
247 /*ARGSUSED*/
248 void
249 cv_init(kcondvar_t *cv, char *name, int type, void *arg)
250 {
251 	VERIFY(cond_init(cv, type, NULL) == 0);
252 }
253 
254 void
255 cv_destroy(kcondvar_t *cv)
256 {
257 	VERIFY(cond_destroy(cv) == 0);
258 }
259 
260 void
261 cv_wait(kcondvar_t *cv, kmutex_t *mp)
262 {
263 	ASSERT(mutex_owner(mp) == curthread);
264 	mp->m_owner = NULL;
265 	int ret = cond_wait(cv, &mp->m_lock);
266 	VERIFY(ret == 0 || ret == EINTR);
267 	mp->m_owner = curthread;
268 }
269 
270 clock_t
271 cv_timedwait(kcondvar_t *cv, kmutex_t *mp, clock_t abstime)
272 {
273 	int error;
274 	timestruc_t ts;
275 	clock_t delta;
276 
277 top:
278 	delta = abstime - ddi_get_lbolt();
279 	if (delta <= 0)
280 		return (-1);
281 
282 	ts.tv_sec = delta / hz;
283 	ts.tv_nsec = (delta % hz) * (NANOSEC / hz);
284 
285 	ASSERT(mutex_owner(mp) == curthread);
286 	mp->m_owner = NULL;
287 	error = cond_reltimedwait(cv, &mp->m_lock, &ts);
288 	mp->m_owner = curthread;
289 
290 	if (error == ETIME)
291 		return (-1);
292 
293 	if (error == EINTR)
294 		goto top;
295 
296 	ASSERT(error == 0);
297 
298 	return (1);
299 }
300 
301 void
302 cv_signal(kcondvar_t *cv)
303 {
304 	VERIFY(cond_signal(cv) == 0);
305 }
306 
307 void
308 cv_broadcast(kcondvar_t *cv)
309 {
310 	VERIFY(cond_broadcast(cv) == 0);
311 }
312 
313 /*
314  * =========================================================================
315  * vnode operations
316  * =========================================================================
317  */
318 /*
319  * Note: for the xxxat() versions of these functions, we assume that the
320  * starting vp is always rootdir (which is true for spa_directory.c, the only
321  * ZFS consumer of these interfaces).  We assert this is true, and then emulate
322  * them by adding '/' in front of the path.
323  */
324 
325 /*ARGSUSED*/
326 int
327 vn_open(char *path, int x1, int flags, int mode, vnode_t **vpp, int x2, int x3)
328 {
329 	int fd;
330 	vnode_t *vp;
331 	int old_umask;
332 	char realpath[MAXPATHLEN];
333 	struct stat64 st;
334 
335 	/*
336 	 * If we're accessing a real disk from userland, we need to use
337 	 * the character interface to avoid caching.  This is particularly
338 	 * important if we're trying to look at a real in-kernel storage
339 	 * pool from userland, e.g. via zdb, because otherwise we won't
340 	 * see the changes occurring under the segmap cache.
341 	 * On the other hand, the stupid character device returns zero
342 	 * for its size.  So -- gag -- we open the block device to get
343 	 * its size, and remember it for subsequent VOP_GETATTR().
344 	 */
345 	if (strncmp(path, "/dev/", 5) == 0) {
346 		char *dsk;
347 		fd = open64(path, O_RDONLY);
348 		if (fd == -1)
349 			return (errno);
350 		if (fstat64(fd, &st) == -1) {
351 			close(fd);
352 			return (errno);
353 		}
354 		close(fd);
355 		(void) sprintf(realpath, "%s", path);
356 		dsk = strstr(path, "/dsk/");
357 		if (dsk != NULL)
358 			(void) sprintf(realpath + (dsk - path) + 1, "r%s",
359 			    dsk + 1);
360 	} else {
361 		(void) sprintf(realpath, "%s", path);
362 		if (!(flags & FCREAT) && stat64(realpath, &st) == -1)
363 			return (errno);
364 	}
365 
366 	if (flags & FCREAT)
367 		old_umask = umask(0);
368 
369 	/*
370 	 * The construct 'flags - FREAD' conveniently maps combinations of
371 	 * FREAD and FWRITE to the corresponding O_RDONLY, O_WRONLY, and O_RDWR.
372 	 */
373 	fd = open64(realpath, flags - FREAD, mode);
374 
375 	if (flags & FCREAT)
376 		(void) umask(old_umask);
377 
378 	if (fd == -1)
379 		return (errno);
380 
381 	if (fstat64(fd, &st) == -1) {
382 		close(fd);
383 		return (errno);
384 	}
385 
386 	(void) fcntl(fd, F_SETFD, FD_CLOEXEC);
387 
388 	*vpp = vp = umem_zalloc(sizeof (vnode_t), UMEM_NOFAIL);
389 
390 	vp->v_fd = fd;
391 	vp->v_size = st.st_size;
392 	vp->v_path = spa_strdup(path);
393 
394 	return (0);
395 }
396 
397 /*ARGSUSED*/
398 int
399 vn_openat(char *path, int x1, int flags, int mode, vnode_t **vpp, int x2,
400     int x3, vnode_t *startvp, int fd)
401 {
402 	char *realpath = umem_alloc(strlen(path) + 2, UMEM_NOFAIL);
403 	int ret;
404 
405 	ASSERT(startvp == rootdir);
406 	(void) sprintf(realpath, "/%s", path);
407 
408 	/* fd ignored for now, need if want to simulate nbmand support */
409 	ret = vn_open(realpath, x1, flags, mode, vpp, x2, x3);
410 
411 	umem_free(realpath, strlen(path) + 2);
412 
413 	return (ret);
414 }
415 
416 /*ARGSUSED*/
417 int
418 vn_rdwr(int uio, vnode_t *vp, void *addr, ssize_t len, offset_t offset,
419 	int x1, int x2, rlim64_t x3, void *x4, ssize_t *residp)
420 {
421 	ssize_t iolen, split;
422 
423 	if (uio == UIO_READ) {
424 		iolen = pread64(vp->v_fd, addr, len, offset);
425 	} else {
426 		/*
427 		 * To simulate partial disk writes, we split writes into two
428 		 * system calls so that the process can be killed in between.
429 		 */
430 		int sectors = len >> SPA_MINBLOCKSHIFT;
431 		split = (sectors > 0 ? rand() % sectors : 0) <<
432 		    SPA_MINBLOCKSHIFT;
433 		iolen = pwrite64(vp->v_fd, addr, split, offset);
434 		iolen += pwrite64(vp->v_fd, (char *)addr + split,
435 		    len - split, offset + split);
436 	}
437 
438 	if (iolen == -1)
439 		return (errno);
440 	if (residp)
441 		*residp = len - iolen;
442 	else if (iolen != len)
443 		return (EIO);
444 	return (0);
445 }
446 
447 void
448 vn_close(vnode_t *vp)
449 {
450 	close(vp->v_fd);
451 	spa_strfree(vp->v_path);
452 	umem_free(vp, sizeof (vnode_t));
453 }
454 
455 /*
456  * At a minimum we need to update the size since vdev_reopen()
457  * will no longer call vn_openat().
458  */
459 int
460 fop_getattr(vnode_t *vp, vattr_t *vap)
461 {
462 	struct stat64 st;
463 
464 	if (fstat64(vp->v_fd, &st) == -1) {
465 		close(vp->v_fd);
466 		return (errno);
467 	}
468 
469 	vap->va_size = st.st_size;
470 	return (0);
471 }
472 
473 #ifdef ZFS_DEBUG
474 
475 /*
476  * =========================================================================
477  * Figure out which debugging statements to print
478  * =========================================================================
479  */
480 
481 static char *dprintf_string;
482 static int dprintf_print_all;
483 
484 int
485 dprintf_find_string(const char *string)
486 {
487 	char *tmp_str = dprintf_string;
488 	int len = strlen(string);
489 
490 	/*
491 	 * Find out if this is a string we want to print.
492 	 * String format: file1.c,function_name1,file2.c,file3.c
493 	 */
494 
495 	while (tmp_str != NULL) {
496 		if (strncmp(tmp_str, string, len) == 0 &&
497 		    (tmp_str[len] == ',' || tmp_str[len] == '\0'))
498 			return (1);
499 		tmp_str = strchr(tmp_str, ',');
500 		if (tmp_str != NULL)
501 			tmp_str++; /* Get rid of , */
502 	}
503 	return (0);
504 }
505 
506 void
507 dprintf_setup(int *argc, char **argv)
508 {
509 	int i, j;
510 
511 	/*
512 	 * Debugging can be specified two ways: by setting the
513 	 * environment variable ZFS_DEBUG, or by including a
514 	 * "debug=..."  argument on the command line.  The command
515 	 * line setting overrides the environment variable.
516 	 */
517 
518 	for (i = 1; i < *argc; i++) {
519 		int len = strlen("debug=");
520 		/* First look for a command line argument */
521 		if (strncmp("debug=", argv[i], len) == 0) {
522 			dprintf_string = argv[i] + len;
523 			/* Remove from args */
524 			for (j = i; j < *argc; j++)
525 				argv[j] = argv[j+1];
526 			argv[j] = NULL;
527 			(*argc)--;
528 		}
529 	}
530 
531 	if (dprintf_string == NULL) {
532 		/* Look for ZFS_DEBUG environment variable */
533 		dprintf_string = getenv("ZFS_DEBUG");
534 	}
535 
536 	/*
537 	 * Are we just turning on all debugging?
538 	 */
539 	if (dprintf_find_string("on"))
540 		dprintf_print_all = 1;
541 }
542 
543 /*
544  * =========================================================================
545  * debug printfs
546  * =========================================================================
547  */
548 void
549 __dprintf(const char *file, const char *func, int line, const char *fmt, ...)
550 {
551 	const char *newfile;
552 	va_list adx;
553 
554 	/*
555 	 * Get rid of annoying "../common/" prefix to filename.
556 	 */
557 	newfile = strrchr(file, '/');
558 	if (newfile != NULL) {
559 		newfile = newfile + 1; /* Get rid of leading / */
560 	} else {
561 		newfile = file;
562 	}
563 
564 	if (dprintf_print_all ||
565 	    dprintf_find_string(newfile) ||
566 	    dprintf_find_string(func)) {
567 		/* Print out just the function name if requested */
568 		flockfile(stdout);
569 		if (dprintf_find_string("pid"))
570 			(void) printf("%d ", getpid());
571 		if (dprintf_find_string("tid"))
572 			(void) printf("%u ", thr_self());
573 		if (dprintf_find_string("cpu"))
574 			(void) printf("%u ", getcpuid());
575 		if (dprintf_find_string("time"))
576 			(void) printf("%llu ", gethrtime());
577 		if (dprintf_find_string("long"))
578 			(void) printf("%s, line %d: ", newfile, line);
579 		(void) printf("%s: ", func);
580 		va_start(adx, fmt);
581 		(void) vprintf(fmt, adx);
582 		va_end(adx);
583 		funlockfile(stdout);
584 	}
585 }
586 
587 #endif /* ZFS_DEBUG */
588 
589 /*
590  * =========================================================================
591  * cmn_err() and panic()
592  * =========================================================================
593  */
594 static char ce_prefix[CE_IGNORE][10] = { "", "NOTICE: ", "WARNING: ", "" };
595 static char ce_suffix[CE_IGNORE][2] = { "", "\n", "\n", "" };
596 
597 void
598 vpanic(const char *fmt, va_list adx)
599 {
600 	(void) fprintf(stderr, "error: ");
601 	(void) vfprintf(stderr, fmt, adx);
602 	(void) fprintf(stderr, "\n");
603 
604 	abort();	/* think of it as a "user-level crash dump" */
605 }
606 
607 void
608 panic(const char *fmt, ...)
609 {
610 	va_list adx;
611 
612 	va_start(adx, fmt);
613 	vpanic(fmt, adx);
614 	va_end(adx);
615 }
616 
617 void
618 vcmn_err(int ce, const char *fmt, va_list adx)
619 {
620 	if (ce == CE_PANIC)
621 		vpanic(fmt, adx);
622 	if (ce != CE_NOTE) {	/* suppress noise in userland stress testing */
623 		(void) fprintf(stderr, "%s", ce_prefix[ce]);
624 		(void) vfprintf(stderr, fmt, adx);
625 		(void) fprintf(stderr, "%s", ce_suffix[ce]);
626 	}
627 }
628 
629 /*PRINTFLIKE2*/
630 void
631 cmn_err(int ce, const char *fmt, ...)
632 {
633 	va_list adx;
634 
635 	va_start(adx, fmt);
636 	vcmn_err(ce, fmt, adx);
637 	va_end(adx);
638 }
639 
640 /*
641  * =========================================================================
642  * kobj interfaces
643  * =========================================================================
644  */
645 struct _buf *
646 kobj_open_file(char *name)
647 {
648 	struct _buf *file;
649 	vnode_t *vp;
650 
651 	/* set vp as the _fd field of the file */
652 	if (vn_openat(name, UIO_SYSSPACE, FREAD, 0, &vp, 0, 0, rootdir,
653 	    -1) != 0)
654 		return ((void *)-1UL);
655 
656 	file = umem_zalloc(sizeof (struct _buf), UMEM_NOFAIL);
657 	file->_fd = (intptr_t)vp;
658 	return (file);
659 }
660 
661 int
662 kobj_read_file(struct _buf *file, char *buf, unsigned size, unsigned off)
663 {
664 	ssize_t resid;
665 
666 	vn_rdwr(UIO_READ, (vnode_t *)file->_fd, buf, size, (offset_t)off,
667 	    UIO_SYSSPACE, 0, 0, 0, &resid);
668 
669 	return (size - resid);
670 }
671 
672 void
673 kobj_close_file(struct _buf *file)
674 {
675 	vn_close((vnode_t *)file->_fd);
676 	umem_free(file, sizeof (struct _buf));
677 }
678 
679 int
680 kobj_get_filesize(struct _buf *file, uint64_t *size)
681 {
682 	struct stat64 st;
683 	vnode_t *vp = (vnode_t *)file->_fd;
684 
685 	if (fstat64(vp->v_fd, &st) == -1) {
686 		vn_close(vp);
687 		return (errno);
688 	}
689 	*size = st.st_size;
690 	return (0);
691 }
692 
693 /*
694  * =========================================================================
695  * misc routines
696  * =========================================================================
697  */
698 
699 void
700 delay(clock_t ticks)
701 {
702 	poll(0, 0, ticks * (1000 / hz));
703 }
704 
705 /*
706  * Find highest one bit set.
707  *	Returns bit number + 1 of highest bit that is set, otherwise returns 0.
708  * High order bit is 31 (or 63 in _LP64 kernel).
709  */
710 int
711 highbit(ulong_t i)
712 {
713 	register int h = 1;
714 
715 	if (i == 0)
716 		return (0);
717 #ifdef _LP64
718 	if (i & 0xffffffff00000000ul) {
719 		h += 32; i >>= 32;
720 	}
721 #endif
722 	if (i & 0xffff0000) {
723 		h += 16; i >>= 16;
724 	}
725 	if (i & 0xff00) {
726 		h += 8; i >>= 8;
727 	}
728 	if (i & 0xf0) {
729 		h += 4; i >>= 4;
730 	}
731 	if (i & 0xc) {
732 		h += 2; i >>= 2;
733 	}
734 	if (i & 0x2) {
735 		h += 1;
736 	}
737 	return (h);
738 }
739 
740 static int random_fd = -1, urandom_fd = -1;
741 
742 static int
743 random_get_bytes_common(uint8_t *ptr, size_t len, int fd)
744 {
745 	size_t resid = len;
746 	ssize_t bytes;
747 
748 	ASSERT(fd != -1);
749 
750 	while (resid != 0) {
751 		bytes = read(fd, ptr, resid);
752 		ASSERT3S(bytes, >=, 0);
753 		ptr += bytes;
754 		resid -= bytes;
755 	}
756 
757 	return (0);
758 }
759 
760 int
761 random_get_bytes(uint8_t *ptr, size_t len)
762 {
763 	return (random_get_bytes_common(ptr, len, random_fd));
764 }
765 
766 int
767 random_get_pseudo_bytes(uint8_t *ptr, size_t len)
768 {
769 	return (random_get_bytes_common(ptr, len, urandom_fd));
770 }
771 
772 int
773 ddi_strtoul(const char *hw_serial, char **nptr, int base, unsigned long *result)
774 {
775 	char *end;
776 
777 	*result = strtoul(hw_serial, &end, base);
778 	if (*result == 0)
779 		return (errno);
780 	return (0);
781 }
782 
783 int
784 ddi_strtoull(const char *str, char **nptr, int base, u_longlong_t *result)
785 {
786 	char *end;
787 
788 	*result = strtoull(str, &end, base);
789 	if (*result == 0)
790 		return (errno);
791 	return (0);
792 }
793 
794 /* ARGSUSED */
795 cyclic_id_t
796 cyclic_add(cyc_handler_t *hdlr, cyc_time_t *when)
797 {
798 	return (1);
799 }
800 
801 /* ARGSUSED */
802 void
803 cyclic_remove(cyclic_id_t id)
804 {
805 }
806 
807 /* ARGSUSED */
808 int
809 cyclic_reprogram(cyclic_id_t id, hrtime_t expiration)
810 {
811 	return (1);
812 }
813 
814 /*
815  * =========================================================================
816  * kernel emulation setup & teardown
817  * =========================================================================
818  */
819 static int
820 umem_out_of_memory(void)
821 {
822 	char errmsg[] = "out of memory -- generating core dump\n";
823 
824 	write(fileno(stderr), errmsg, sizeof (errmsg));
825 	abort();
826 	return (0);
827 }
828 
829 void
830 kernel_init(int mode)
831 {
832 	umem_nofail_callback(umem_out_of_memory);
833 
834 	physmem = sysconf(_SC_PHYS_PAGES);
835 
836 	dprintf("physmem = %llu pages (%.2f GB)\n", physmem,
837 	    (double)physmem * sysconf(_SC_PAGE_SIZE) / (1ULL << 30));
838 
839 	(void) snprintf(hw_serial, sizeof (hw_serial), "%ld",
840 	    (mode & FWRITE) ? gethostid() : 0);
841 
842 	VERIFY((random_fd = open("/dev/random", O_RDONLY)) != -1);
843 	VERIFY((urandom_fd = open("/dev/urandom", O_RDONLY)) != -1);
844 
845 	system_taskq_init();
846 
847 	mutex_init(&cpu_lock, NULL, MUTEX_DEFAULT, NULL);
848 
849 	spa_init(mode);
850 }
851 
852 void
853 kernel_fini(void)
854 {
855 	spa_fini();
856 
857 	system_taskq_fini();
858 
859 	close(random_fd);
860 	close(urandom_fd);
861 
862 	random_fd = -1;
863 	urandom_fd = -1;
864 }
865 
866 int
867 z_uncompress(void *dst, size_t *dstlen, const void *src, size_t srclen)
868 {
869 	int ret;
870 	uLongf len = *dstlen;
871 
872 	if ((ret = uncompress(dst, &len, src, srclen)) == Z_OK)
873 		*dstlen = (size_t)len;
874 
875 	return (ret);
876 }
877 
878 int
879 z_compress_level(void *dst, size_t *dstlen, const void *src, size_t srclen,
880     int level)
881 {
882 	int ret;
883 	uLongf len = *dstlen;
884 
885 	if ((ret = compress2(dst, &len, src, srclen, level)) == Z_OK)
886 		*dstlen = (size_t)len;
887 
888 	return (ret);
889 }
890 
891 uid_t
892 crgetuid(cred_t *cr)
893 {
894 	return (0);
895 }
896 
897 uid_t
898 crgetruid(cred_t *cr)
899 {
900 	return (0);
901 }
902 
903 gid_t
904 crgetgid(cred_t *cr)
905 {
906 	return (0);
907 }
908 
909 int
910 crgetngroups(cred_t *cr)
911 {
912 	return (0);
913 }
914 
915 gid_t *
916 crgetgroups(cred_t *cr)
917 {
918 	return (NULL);
919 }
920 
921 int
922 zfs_secpolicy_snapshot_perms(const char *name, cred_t *cr)
923 {
924 	return (0);
925 }
926 
927 int
928 zfs_secpolicy_rename_perms(const char *from, const char *to, cred_t *cr)
929 {
930 	return (0);
931 }
932 
933 int
934 zfs_secpolicy_destroy_perms(const char *name, cred_t *cr)
935 {
936 	return (0);
937 }
938 
939 ksiddomain_t *
940 ksid_lookupdomain(const char *dom)
941 {
942 	ksiddomain_t *kd;
943 
944 	kd = umem_zalloc(sizeof (ksiddomain_t), UMEM_NOFAIL);
945 	kd->kd_name = spa_strdup(dom);
946 	return (kd);
947 }
948 
949 void
950 ksiddomain_rele(ksiddomain_t *ksid)
951 {
952 	spa_strfree(ksid->kd_name);
953 	umem_free(ksid, sizeof (ksiddomain_t));
954 }
955 
956 /*
957  * Do not change the length of the returned string; it must be freed
958  * with strfree().
959  */
960 char *
961 kmem_asprintf(const char *fmt, ...)
962 {
963 	int size;
964 	va_list adx;
965 	char *buf;
966 
967 	va_start(adx, fmt);
968 	size = vsnprintf(NULL, 0, fmt, adx) + 1;
969 	va_end(adx);
970 
971 	buf = kmem_alloc(size, KM_SLEEP);
972 
973 	va_start(adx, fmt);
974 	size = vsnprintf(buf, size, fmt, adx);
975 	va_end(adx);
976 
977 	return (buf);
978 }
979 
980 /* ARGSUSED */
981 int
982 zfs_onexit_fd_hold(int fd, minor_t *minorp)
983 {
984 	*minorp = 0;
985 	return (0);
986 }
987 
988 /* ARGSUSED */
989 void
990 zfs_onexit_fd_rele(int fd)
991 {
992 }
993 
994 /* ARGSUSED */
995 int
996 zfs_onexit_add_cb(minor_t minor, void (*func)(void *), void *data,
997     uint64_t *action_handle)
998 {
999 	return (0);
1000 }
1001 
1002 /* ARGSUSED */
1003 int
1004 zfs_onexit_del_cb(minor_t minor, uint64_t action_handle, boolean_t fire)
1005 {
1006 	return (0);
1007 }
1008 
1009 /* ARGSUSED */
1010 int
1011 zfs_onexit_cb_data(minor_t minor, uint64_t action_handle, void **data)
1012 {
1013 	return (0);
1014 }
1015 
1016 void
1017 bioinit(buf_t *bp)
1018 {
1019 	bzero(bp, sizeof (buf_t));
1020 }
1021 
1022 void
1023 biodone(buf_t *bp)
1024 {
1025 	if (bp->b_iodone != NULL) {
1026 		(*(bp->b_iodone))(bp);
1027 		return;
1028 	}
1029 	ASSERT((bp->b_flags & B_DONE) == 0);
1030 	bp->b_flags |= B_DONE;
1031 }
1032 
1033 void
1034 bioerror(buf_t *bp, int error)
1035 {
1036 	ASSERT(bp != NULL);
1037 	ASSERT(error >= 0);
1038 
1039 	if (error != 0) {
1040 		bp->b_flags |= B_ERROR;
1041 	} else {
1042 		bp->b_flags &= ~B_ERROR;
1043 	}
1044 	bp->b_error = error;
1045 }
1046 
1047 
1048 int
1049 geterror(struct buf *bp)
1050 {
1051 	int error = 0;
1052 
1053 	if (bp->b_flags & B_ERROR) {
1054 		error = bp->b_error;
1055 		if (!error)
1056 			error = EIO;
1057 	}
1058 	return (error);
1059 }
1060