xref: /titanic_41/usr/src/cmd/zinject/zinject.c (revision 9a5557fdd04be37785607871e8d4189e39490129)
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 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 /*
29  * ZFS Fault Injector
30  *
31  * This userland component takes a set of options and uses libzpool to translate
32  * from a user-visible object type and name to an internal representation.
33  * There are two basic types of faults: device faults and data faults.
34  *
35  *
36  * DEVICE FAULTS
37  *
38  * Errors can be injected into a particular vdev using the '-d' option.  This
39  * option takes a path or vdev GUID to uniquely identify the device within a
40  * pool.  There are two types of errors that can be injected, EIO and ENXIO,
41  * that can be controlled through the '-e' option.  The default is ENXIO.  For
42  * EIO failures, any attempt to read data from the device will return EIO, but
43  * subsequent attempt to reopen the device will succeed.  For ENXIO failures,
44  * any attempt to read from the device will return EIO, but any attempt to
45  * reopen the device will also return ENXIO.
46  * For label faults, the -L option must be specified. This allows faults
47  * to be injected into either the nvlist or uberblock region of all the labels
48  * for the specified device.
49  *
50  * This form of the command looks like:
51  *
52  * 	zinject -d device [-e errno] [-L <uber | nvlist>] pool
53  *
54  *
55  * DATA FAULTS
56  *
57  * We begin with a tuple of the form:
58  *
59  * 	<type,level,range,object>
60  *
61  * 	type	A string describing the type of data to target.  Each type
62  * 		implicitly describes how to interpret 'object'. Currently,
63  * 		the following values are supported:
64  *
65  * 		data		User data for a file
66  * 		dnode		Dnode for a file or directory
67  *
68  *		The following MOS objects are special.  Instead of injecting
69  *		errors on a particular object or blkid, we inject errors across
70  *		all objects of the given type.
71  *
72  * 		mos		Any data in the MOS
73  * 		mosdir		object directory
74  * 		config		pool configuration
75  * 		bplist		blkptr list
76  * 		spacemap	spacemap
77  * 		metaslab	metaslab
78  * 		errlog		persistent error log
79  *
80  * 	level	Object level.  Defaults to '0', not applicable to all types.  If
81  * 		a range is given, this corresponds to the indirect block
82  * 		corresponding to the specific range.
83  *
84  *	range	A numerical range [start,end) within the object.  Defaults to
85  *		the full size of the file.
86  *
87  * 	object	A string describing the logical location of the object.  For
88  * 		files and directories (currently the only supported types),
89  * 		this is the path of the object on disk.
90  *
91  * This is translated, via libzpool, into the following internal representation:
92  *
93  * 	<type,objset,object,level,range>
94  *
95  * These types should be self-explanatory.  This tuple is then passed to the
96  * kernel via a special ioctl() to initiate fault injection for the given
97  * object.  Note that 'type' is not strictly necessary for fault injection, but
98  * is used when translating existing faults into a human-readable string.
99  *
100  *
101  * The command itself takes one of the forms:
102  *
103  * 	zinject
104  * 	zinject <-a | -u pool>
105  * 	zinject -c <id|all>
106  * 	zinject [-q] <-t type> [-f freq] [-u] [-a] [-m] [-e errno] [-l level]
107  *	    [-r range] <object>
108  * 	zinject [-f freq] [-a] [-m] [-u] -b objset:object:level:start:end pool
109  *
110  * With no arguments, the command prints all currently registered injection
111  * handlers, with their numeric identifiers.
112  *
113  * The '-c' option will clear the given handler, or all handlers if 'all' is
114  * specified.
115  *
116  * The '-e' option takes a string describing the errno to simulate.  This must
117  * be either 'io' or 'checksum'.  In most cases this will result in the same
118  * behavior, but RAID-Z will produce a different set of ereports for this
119  * situation.
120  *
121  * The '-a', '-u', and '-m' flags toggle internal flush behavior.  If '-a' is
122  * specified, then the ARC cache is flushed appropriately.  If '-u' is
123  * specified, then the underlying SPA is unloaded.  Either of these flags can be
124  * specified independently of any other handlers.  The '-m' flag automatically
125  * does an unmount and remount of the underlying dataset to aid in flushing the
126  * cache.
127  *
128  * The '-f' flag controls the frequency of errors injected, expressed as a
129  * integer percentage between 1 and 100.  The default is 100.
130  *
131  * The this form is responsible for actually injecting the handler into the
132  * framework.  It takes the arguments described above, translates them to the
133  * internal tuple using libzpool, and then issues an ioctl() to register the
134  * handler.
135  *
136  * The final form can target a specific bookmark, regardless of whether a
137  * human-readable interface has been designed.  It allows developers to specify
138  * a particular block by number.
139  */
140 
141 #include <errno.h>
142 #include <fcntl.h>
143 #include <stdio.h>
144 #include <stdlib.h>
145 #include <strings.h>
146 #include <unistd.h>
147 
148 #include <sys/fs/zfs.h>
149 #include <sys/mount.h>
150 
151 #include <libzfs.h>
152 
153 #undef verify	/* both libzfs.h and zfs_context.h want to define this */
154 
155 #include "zinject.h"
156 
157 libzfs_handle_t *g_zfs;
158 int zfs_fd;
159 
160 #define	ECKSUM	EBADE
161 
162 static const char *errtable[TYPE_INVAL] = {
163 	"data",
164 	"dnode",
165 	"mos",
166 	"mosdir",
167 	"metaslab",
168 	"config",
169 	"bplist",
170 	"spacemap",
171 	"errlog",
172 	"uber",
173 	"nvlist"
174 };
175 
176 static err_type_t
177 name_to_type(const char *arg)
178 {
179 	int i;
180 	for (i = 0; i < TYPE_INVAL; i++)
181 		if (strcmp(errtable[i], arg) == 0)
182 			return (i);
183 
184 	return (TYPE_INVAL);
185 }
186 
187 static const char *
188 type_to_name(uint64_t type)
189 {
190 	switch (type) {
191 	case DMU_OT_OBJECT_DIRECTORY:
192 		return ("mosdir");
193 	case DMU_OT_OBJECT_ARRAY:
194 		return ("metaslab");
195 	case DMU_OT_PACKED_NVLIST:
196 		return ("config");
197 	case DMU_OT_BPLIST:
198 		return ("bplist");
199 	case DMU_OT_SPACE_MAP:
200 		return ("spacemap");
201 	case DMU_OT_ERROR_LOG:
202 		return ("errlog");
203 	default:
204 		return ("-");
205 	}
206 }
207 
208 
209 /*
210  * Print usage message.
211  */
212 void
213 usage(void)
214 {
215 	(void) printf(
216 	    "usage:\n"
217 	    "\n"
218 	    "\tzinject\n"
219 	    "\n"
220 	    "\t\tList all active injection records.\n"
221 	    "\n"
222 	    "\tzinject -c <id|all>\n"
223 	    "\n"
224 	    "\t\tClear the particular record (if given a numeric ID), or\n"
225 	    "\t\tall records if 'all' is specificed.\n"
226 	    "\n"
227 	    "\tzinject -d device [-e errno] [-L <nvlist|uber>] pool\n"
228 	    "\t\tInject a fault into a particular device or the device's\n"
229 	    "\t\tlabel.  Label injection can either be 'nvlist' or 'uber'.\n"
230 	    "\t\t'errno' can either be 'nxio' (the default) or 'io'.\n"
231 	    "\n"
232 	    "\tzinject -b objset:object:level:blkid pool\n"
233 	    "\n"
234 	    "\t\tInject an error into pool 'pool' with the numeric bookmark\n"
235 	    "\t\tspecified by the remaining tuple.  Each number is in\n"
236 	    "\t\thexidecimal, and only one block can be specified.\n"
237 	    "\n"
238 	    "\tzinject [-q] <-t type> [-e errno] [-l level] [-r range]\n"
239 	    "\t    [-a] [-m] [-u] [-f freq] <object>\n"
240 	    "\n"
241 	    "\t\tInject an error into the object specified by the '-t' option\n"
242 	    "\t\tand the object descriptor.  The 'object' parameter is\n"
243 	    "\t\tinterperted depending on the '-t' option.\n"
244 	    "\n"
245 	    "\t\t-q\tQuiet mode.  Only print out the handler number added.\n"
246 	    "\t\t-e\tInject a specific error.  Must be either 'io' or\n"
247 	    "\t\t\t'checksum'.  Default is 'io'.\n"
248 	    "\t\t-l\tInject error at a particular block level. Default is "
249 	    "0.\n"
250 	    "\t\t-m\tAutomatically remount underlying filesystem.\n"
251 	    "\t\t-r\tInject error over a particular logical range of an\n"
252 	    "\t\t\tobject.  Will be translated to the appropriate blkid\n"
253 	    "\t\t\trange according to the object's properties.\n"
254 	    "\t\t-a\tFlush the ARC cache.  Can be specified without any\n"
255 	    "\t\t\tassociated object.\n"
256 	    "\t\t-u\tUnload the associated pool.  Can be specified with only\n"
257 	    "\t\t\ta pool object.\n"
258 	    "\t\t-f\tOnly inject errors a fraction of the time.  Expressed as\n"
259 	    "\t\t\ta percentage between 1 and 100.\n"
260 	    "\n"
261 	    "\t-t data\t\tInject an error into the plain file contents of a\n"
262 	    "\t\t\tfile.  The object must be specified as a complete path\n"
263 	    "\t\t\tto a file on a ZFS filesystem.\n"
264 	    "\n"
265 	    "\t-t dnode\tInject an error into the metadnode in the block\n"
266 	    "\t\t\tcorresponding to the dnode for a file or directory.  The\n"
267 	    "\t\t\t'-r' option is incompatible with this mode.  The object\n"
268 	    "\t\t\tis specified as a complete path to a file or directory\n"
269 	    "\t\t\ton a ZFS filesystem.\n"
270 	    "\n"
271 	    "\t-t <mos>\tInject errors into the MOS for objects of the given\n"
272 	    "\t\t\ttype.  Valid types are: mos, mosdir, config, bplist,\n"
273 	    "\t\t\tspacemap, metaslab, errlog.  The only valid <object> is\n"
274 	    "\t\t\tthe poolname.\n");
275 }
276 
277 static int
278 iter_handlers(int (*func)(int, const char *, zinject_record_t *, void *),
279     void *data)
280 {
281 	zfs_cmd_t zc;
282 	int ret;
283 
284 	zc.zc_guid = 0;
285 
286 	while (ioctl(zfs_fd, ZFS_IOC_INJECT_LIST_NEXT, &zc) == 0)
287 		if ((ret = func((int)zc.zc_guid, zc.zc_name,
288 		    &zc.zc_inject_record, data)) != 0)
289 			return (ret);
290 
291 	return (0);
292 }
293 
294 static int
295 print_data_handler(int id, const char *pool, zinject_record_t *record,
296     void *data)
297 {
298 	int *count = data;
299 
300 	if (record->zi_guid != 0)
301 		return (0);
302 
303 	if (*count == 0) {
304 		(void) printf("%3s  %-15s  %-6s  %-6s  %-8s  %3s  %-15s\n",
305 		    "ID", "POOL", "OBJSET", "OBJECT", "TYPE", "LVL",  "RANGE");
306 		(void) printf("---  ---------------  ------  "
307 		    "------  --------  ---  ---------------\n");
308 	}
309 
310 	*count += 1;
311 
312 	(void) printf("%3d  %-15s  %-6llu  %-6llu  %-8s  %3d  ", id, pool,
313 	    (u_longlong_t)record->zi_objset, (u_longlong_t)record->zi_object,
314 	    type_to_name(record->zi_type), record->zi_level);
315 
316 	if (record->zi_start == 0 &&
317 	    record->zi_end == -1ULL)
318 		(void) printf("all\n");
319 	else
320 		(void) printf("[%llu, %llu]\n", (u_longlong_t)record->zi_start,
321 		    (u_longlong_t)record->zi_end);
322 
323 	return (0);
324 }
325 
326 static int
327 print_device_handler(int id, const char *pool, zinject_record_t *record,
328     void *data)
329 {
330 	int *count = data;
331 
332 	if (record->zi_guid == 0)
333 		return (0);
334 
335 	if (*count == 0) {
336 		(void) printf("%3s  %-15s  %s\n", "ID", "POOL", "GUID");
337 		(void) printf("---  ---------------  ----------------\n");
338 	}
339 
340 	*count += 1;
341 
342 	(void) printf("%3d  %-15s  %llx\n", id, pool,
343 	    (u_longlong_t)record->zi_guid);
344 
345 	return (0);
346 }
347 
348 /*
349  * Print all registered error handlers.  Returns the number of handlers
350  * registered.
351  */
352 static int
353 print_all_handlers(void)
354 {
355 	int count = 0;
356 
357 	(void) iter_handlers(print_device_handler, &count);
358 	(void) printf("\n");
359 	count = 0;
360 	(void) iter_handlers(print_data_handler, &count);
361 
362 	return (count);
363 }
364 
365 /* ARGSUSED */
366 static int
367 cancel_one_handler(int id, const char *pool, zinject_record_t *record,
368     void *data)
369 {
370 	zfs_cmd_t zc;
371 
372 	zc.zc_guid = (uint64_t)id;
373 
374 	if (ioctl(zfs_fd, ZFS_IOC_CLEAR_FAULT, &zc) != 0) {
375 		(void) fprintf(stderr, "failed to remove handler %d: %s\n",
376 		    id, strerror(errno));
377 		return (1);
378 	}
379 
380 	return (0);
381 }
382 
383 /*
384  * Remove all fault injection handlers.
385  */
386 static int
387 cancel_all_handlers(void)
388 {
389 	int ret = iter_handlers(cancel_one_handler, NULL);
390 
391 	(void) printf("removed all registered handlers\n");
392 
393 	return (ret);
394 }
395 
396 /*
397  * Remove a specific fault injection handler.
398  */
399 static int
400 cancel_handler(int id)
401 {
402 	zfs_cmd_t zc;
403 
404 	zc.zc_guid = (uint64_t)id;
405 
406 	if (ioctl(zfs_fd, ZFS_IOC_CLEAR_FAULT, &zc) != 0) {
407 		(void) fprintf(stderr, "failed to remove handler %d: %s\n",
408 		    id, strerror(errno));
409 		return (1);
410 	}
411 
412 	(void) printf("removed handler %d\n", id);
413 
414 	return (0);
415 }
416 
417 /*
418  * Register a new fault injection handler.
419  */
420 static int
421 register_handler(const char *pool, int flags, zinject_record_t *record,
422     int quiet)
423 {
424 	zfs_cmd_t zc;
425 
426 	(void) strcpy(zc.zc_name, pool);
427 	zc.zc_inject_record = *record;
428 	zc.zc_guid = flags;
429 
430 	if (ioctl(zfs_fd, ZFS_IOC_INJECT_FAULT, &zc) != 0) {
431 		(void) fprintf(stderr, "failed to add handler: %s\n",
432 		    strerror(errno));
433 		return (1);
434 	}
435 
436 	if (flags & ZINJECT_NULL)
437 		return (0);
438 
439 	if (quiet) {
440 		(void) printf("%llu\n", (u_longlong_t)zc.zc_guid);
441 	} else {
442 		(void) printf("Added handler %llu with the following "
443 		    "properties:\n", (u_longlong_t)zc.zc_guid);
444 		(void) printf("  pool: %s\n", pool);
445 		if (record->zi_guid) {
446 			(void) printf("  vdev: %llx\n",
447 			    (u_longlong_t)record->zi_guid);
448 		} else {
449 			(void) printf("objset: %llu\n",
450 			    (u_longlong_t)record->zi_objset);
451 			(void) printf("object: %llu\n",
452 			    (u_longlong_t)record->zi_object);
453 			(void) printf("  type: %llu\n",
454 			    (u_longlong_t)record->zi_type);
455 			(void) printf(" level: %d\n", record->zi_level);
456 			if (record->zi_start == 0 &&
457 			    record->zi_end == -1ULL)
458 				(void) printf(" range: all\n");
459 			else
460 				(void) printf(" range: [%llu, %llu)\n",
461 				    (u_longlong_t)record->zi_start,
462 				    (u_longlong_t)record->zi_end);
463 		}
464 	}
465 
466 	return (0);
467 }
468 
469 int
470 main(int argc, char **argv)
471 {
472 	int c;
473 	char *range = NULL;
474 	char *cancel = NULL;
475 	char *end;
476 	char *raw = NULL;
477 	char *device = NULL;
478 	int level = 0;
479 	int quiet = 0;
480 	int error = 0;
481 	int domount = 0;
482 	err_type_t type = TYPE_INVAL;
483 	err_type_t label = TYPE_INVAL;
484 	zinject_record_t record = { 0 };
485 	char pool[MAXNAMELEN];
486 	char dataset[MAXNAMELEN];
487 	zfs_handle_t *zhp;
488 	int ret;
489 	int flags = 0;
490 
491 	if ((g_zfs = libzfs_init()) == NULL) {
492 		(void) fprintf(stderr, "internal error: failed to "
493 		    "initialize ZFS library\n");
494 		return (1);
495 	}
496 
497 	libzfs_print_on_error(g_zfs, B_TRUE);
498 
499 	if ((zfs_fd = open(ZFS_DEV, O_RDWR)) < 0) {
500 		(void) fprintf(stderr, "failed to open ZFS device\n");
501 		return (1);
502 	}
503 
504 	if (argc == 1) {
505 		/*
506 		 * No arguments.  Print the available handlers.  If there are no
507 		 * available handlers, direct the user to '-h' for help
508 		 * information.
509 		 */
510 		if (print_all_handlers() == 0) {
511 			(void) printf("No handlers registered.\n");
512 			(void) printf("Run 'zinject -h' for usage "
513 			    "information.\n");
514 		}
515 
516 		return (0);
517 	}
518 
519 	while ((c = getopt(argc, argv, ":ab:d:f:qhc:t:l:mr:e:uL:")) != -1) {
520 		switch (c) {
521 		case 'a':
522 			flags |= ZINJECT_FLUSH_ARC;
523 			break;
524 		case 'b':
525 			raw = optarg;
526 			break;
527 		case 'c':
528 			cancel = optarg;
529 			break;
530 		case 'd':
531 			device = optarg;
532 			break;
533 		case 'e':
534 			if (strcasecmp(optarg, "io") == 0) {
535 				error = EIO;
536 			} else if (strcasecmp(optarg, "checksum") == 0) {
537 				error = ECKSUM;
538 			} else if (strcasecmp(optarg, "nxio") == 0) {
539 				error = ENXIO;
540 			} else {
541 				(void) fprintf(stderr, "invalid error type "
542 				    "'%s': must be 'io', 'checksum' or "
543 				    "'nxio'\n", optarg);
544 				usage();
545 				return (1);
546 			}
547 			break;
548 		case 'f':
549 			record.zi_freq = atoi(optarg);
550 			if (record.zi_freq < 1 || record.zi_freq > 100) {
551 				(void) fprintf(stderr, "frequency range must "
552 				    "be in the range (0, 100]\n");
553 				return (1);
554 			}
555 			break;
556 		case 'h':
557 			usage();
558 			return (0);
559 		case 'l':
560 			level = (int)strtol(optarg, &end, 10);
561 			if (*end != '\0') {
562 				(void) fprintf(stderr, "invalid level '%s': "
563 				    "must be an integer\n", optarg);
564 				usage();
565 				return (1);
566 			}
567 			break;
568 		case 'm':
569 			domount = 1;
570 			break;
571 		case 'q':
572 			quiet = 1;
573 			break;
574 		case 'r':
575 			range = optarg;
576 			break;
577 		case 't':
578 			if ((type = name_to_type(optarg)) == TYPE_INVAL &&
579 			    !MOS_TYPE(type)) {
580 				(void) fprintf(stderr, "invalid type '%s'\n",
581 				    optarg);
582 				usage();
583 				return (1);
584 			}
585 			break;
586 		case 'u':
587 			flags |= ZINJECT_UNLOAD_SPA;
588 			break;
589 		case 'L':
590 			if ((label = name_to_type(optarg)) == TYPE_INVAL &&
591 			    !LABEL_TYPE(type)) {
592 				(void) fprintf(stderr, "invalid label type "
593 				    "'%s'\n", optarg);
594 				usage();
595 				return (1);
596 			}
597 			break;
598 		case ':':
599 			(void) fprintf(stderr, "option -%c requires an "
600 			    "operand\n", optopt);
601 			usage();
602 			return (1);
603 		case '?':
604 			(void) fprintf(stderr, "invalid option '%c'\n",
605 			    optopt);
606 			usage();
607 			return (2);
608 		}
609 	}
610 
611 	argc -= optind;
612 	argv += optind;
613 
614 	if (cancel != NULL) {
615 		/*
616 		 * '-c' is invalid with any other options.
617 		 */
618 		if (raw != NULL || range != NULL || type != TYPE_INVAL ||
619 		    level != 0) {
620 			(void) fprintf(stderr, "cancel (-c) incompatible with "
621 			    "any other options\n");
622 			usage();
623 			return (2);
624 		}
625 		if (argc != 0) {
626 			(void) fprintf(stderr, "extraneous argument to '-c'\n");
627 			usage();
628 			return (2);
629 		}
630 
631 		if (strcmp(cancel, "all") == 0) {
632 			return (cancel_all_handlers());
633 		} else {
634 			int id = (int)strtol(cancel, &end, 10);
635 			if (*end != '\0') {
636 				(void) fprintf(stderr, "invalid handle id '%s':"
637 				    " must be an integer or 'all'\n", cancel);
638 				usage();
639 				return (1);
640 			}
641 			return (cancel_handler(id));
642 		}
643 	}
644 
645 	if (device != NULL) {
646 		/*
647 		 * Device (-d) injection uses a completely different mechanism
648 		 * for doing injection, so handle it separately here.
649 		 */
650 		if (raw != NULL || range != NULL || type != TYPE_INVAL ||
651 		    level != 0) {
652 			(void) fprintf(stderr, "device (-d) incompatible with "
653 			    "data error injection\n");
654 			usage();
655 			return (2);
656 		}
657 
658 		if (argc != 1) {
659 			(void) fprintf(stderr, "device (-d) injection requires "
660 			    "a single pool name\n");
661 			usage();
662 			return (2);
663 		}
664 
665 		(void) strcpy(pool, argv[0]);
666 		dataset[0] = '\0';
667 
668 		if (error == ECKSUM) {
669 			(void) fprintf(stderr, "device error type must be "
670 			    "'io' or 'nxio'\n");
671 			return (1);
672 		}
673 
674 		if (translate_device(pool, device, label, &record) != 0)
675 			return (1);
676 		if (!error)
677 			error = ENXIO;
678 	} else if (raw != NULL) {
679 		if (range != NULL || type != TYPE_INVAL || level != 0) {
680 			(void) fprintf(stderr, "raw (-b) format with "
681 			    "any other options\n");
682 			usage();
683 			return (2);
684 		}
685 
686 		if (argc != 1) {
687 			(void) fprintf(stderr, "raw (-b) format expects a "
688 			    "single pool name\n");
689 			usage();
690 			return (2);
691 		}
692 
693 		(void) strcpy(pool, argv[0]);
694 		dataset[0] = '\0';
695 
696 		if (error == ENXIO) {
697 			(void) fprintf(stderr, "data error type must be "
698 			    "'checksum' or 'io'\n");
699 			return (1);
700 		}
701 
702 		if (translate_raw(raw, &record) != 0)
703 			return (1);
704 		if (!error)
705 			error = EIO;
706 	} else if (type == TYPE_INVAL) {
707 		if (flags == 0) {
708 			(void) fprintf(stderr, "at least one of '-b', '-d', "
709 			    "'-t', '-a', or '-u' must be specified\n");
710 			usage();
711 			return (2);
712 		}
713 
714 		if (argc == 1 && (flags & ZINJECT_UNLOAD_SPA)) {
715 			(void) strcpy(pool, argv[0]);
716 			dataset[0] = '\0';
717 		} else if (argc != 0) {
718 			(void) fprintf(stderr, "extraneous argument for "
719 			    "'-f'\n");
720 			usage();
721 			return (2);
722 		}
723 
724 		flags |= ZINJECT_NULL;
725 	} else {
726 		if (argc != 1) {
727 			(void) fprintf(stderr, "missing object\n");
728 			usage();
729 			return (2);
730 		}
731 
732 		if (error == ENXIO) {
733 			(void) fprintf(stderr, "data error type must be "
734 			    "'checksum' or 'io'\n");
735 			return (1);
736 		}
737 
738 		if (translate_record(type, argv[0], range, level, &record, pool,
739 		    dataset) != 0)
740 			return (1);
741 		if (!error)
742 			error = EIO;
743 	}
744 
745 	/*
746 	 * If this is pool-wide metadata, unmount everything.  The ioctl() will
747 	 * unload the pool, so that we trigger spa-wide reopen of metadata next
748 	 * time we access the pool.
749 	 */
750 	if (dataset[0] != '\0' && domount) {
751 		if ((zhp = zfs_open(g_zfs, dataset, ZFS_TYPE_DATASET)) == NULL)
752 			return (1);
753 
754 		if (zfs_unmount(zhp, NULL, 0) != 0)
755 			return (1);
756 	}
757 
758 	record.zi_error = error;
759 
760 	ret = register_handler(pool, flags, &record, quiet);
761 
762 	if (dataset[0] != '\0' && domount)
763 		ret = (zfs_mount(zhp, NULL, 0) != 0);
764 
765 	libzfs_fini(g_zfs);
766 
767 	return (ret);
768 }
769