xref: /illumos-gate/usr/src/cmd/mdb/common/modules/zfs/zfs.c (revision edb348833aaacfa1176e502ad38875fd0b2717ab)
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 2011 Nexenta Systems, Inc. All rights reserved.
24  * Copyright (c) 2012 by Delphix. All rights reserved.
25  */
26 
27 /* Portions Copyright 2010 Robert Milkowski */
28 
29 #include <mdb/mdb_ctf.h>
30 #include <sys/zfs_context.h>
31 #include <sys/mdb_modapi.h>
32 #include <sys/dbuf.h>
33 #include <sys/dmu_objset.h>
34 #include <sys/dsl_dir.h>
35 #include <sys/dsl_pool.h>
36 #include <sys/metaslab_impl.h>
37 #include <sys/space_map.h>
38 #include <sys/list.h>
39 #include <sys/spa_impl.h>
40 #include <sys/vdev_impl.h>
41 #include <sys/zap_leaf.h>
42 #include <sys/zap_impl.h>
43 #include <ctype.h>
44 #include <sys/zfs_acl.h>
45 #include <sys/sa_impl.h>
46 
47 #ifdef _KERNEL
48 #define	ZFS_OBJ_NAME	"zfs"
49 #else
50 #define	ZFS_OBJ_NAME	"libzpool.so.1"
51 #endif
52 
53 #ifndef _KERNEL
54 int aok;
55 #endif
56 
57 static int
58 getmember(uintptr_t addr, const char *type, mdb_ctf_id_t *idp,
59     const char *member, int len, void *buf)
60 {
61 	mdb_ctf_id_t id;
62 	ulong_t off;
63 	char name[64];
64 
65 	if (idp == NULL) {
66 		if (mdb_ctf_lookup_by_name(type, &id) == -1) {
67 			mdb_warn("couldn't find type %s", type);
68 			return (DCMD_ERR);
69 		}
70 		idp = &id;
71 	} else {
72 		type = name;
73 		mdb_ctf_type_name(*idp, name, sizeof (name));
74 	}
75 
76 	if (mdb_ctf_offsetof(*idp, member, &off) == -1) {
77 		mdb_warn("couldn't find member %s of type %s\n", member, type);
78 		return (DCMD_ERR);
79 	}
80 	if (off % 8 != 0) {
81 		mdb_warn("member %s of type %s is unsupported bitfield",
82 		    member, type);
83 		return (DCMD_ERR);
84 	}
85 	off /= 8;
86 
87 	if (mdb_vread(buf, len, addr + off) == -1) {
88 		mdb_warn("failed to read %s from %s at %p",
89 		    member, type, addr + off);
90 		return (DCMD_ERR);
91 	}
92 	/* mdb_warn("read %s from %s at %p+%llx\n", member, type, addr, off); */
93 
94 	return (0);
95 }
96 
97 #define	GETMEMB(addr, type, member, dest) \
98 	getmember(addr, #type, NULL, #member, sizeof (dest), &(dest))
99 
100 #define	GETMEMBID(addr, ctfid, member, dest) \
101 	getmember(addr, NULL, ctfid, #member, sizeof (dest), &(dest))
102 
103 static int
104 getrefcount(uintptr_t addr, mdb_ctf_id_t *id,
105     const char *member, uint64_t *rc)
106 {
107 	static int gotid;
108 	static mdb_ctf_id_t rc_id;
109 	ulong_t off;
110 
111 	if (!gotid) {
112 		if (mdb_ctf_lookup_by_name("struct refcount", &rc_id) == -1) {
113 			mdb_warn("couldn't find struct refcount");
114 			return (DCMD_ERR);
115 		}
116 		gotid = TRUE;
117 	}
118 
119 	if (mdb_ctf_offsetof(*id, member, &off) == -1) {
120 		char name[64];
121 		mdb_ctf_type_name(*id, name, sizeof (name));
122 		mdb_warn("couldn't find member %s of type %s\n", member, name);
123 		return (DCMD_ERR);
124 	}
125 	off /= 8;
126 
127 	return (GETMEMBID(addr + off, &rc_id, rc_count, *rc));
128 }
129 
130 static boolean_t
131 strisprint(const char *cp)
132 {
133 	for (; *cp; cp++) {
134 		if (!isprint(*cp))
135 			return (B_FALSE);
136 	}
137 	return (B_TRUE);
138 }
139 
140 static int verbose;
141 
142 static int
143 freelist_walk_init(mdb_walk_state_t *wsp)
144 {
145 	if (wsp->walk_addr == NULL) {
146 		mdb_warn("must supply starting address\n");
147 		return (WALK_ERR);
148 	}
149 
150 	wsp->walk_data = 0;  /* Index into the freelist */
151 	return (WALK_NEXT);
152 }
153 
154 static int
155 freelist_walk_step(mdb_walk_state_t *wsp)
156 {
157 	uint64_t entry;
158 	uintptr_t number = (uintptr_t)wsp->walk_data;
159 	char *ddata[] = { "ALLOC", "FREE", "CONDENSE", "INVALID",
160 			    "INVALID", "INVALID", "INVALID", "INVALID" };
161 	int mapshift = SPA_MINBLOCKSHIFT;
162 
163 	if (mdb_vread(&entry, sizeof (entry), wsp->walk_addr) == -1) {
164 		mdb_warn("failed to read freelist entry %p", wsp->walk_addr);
165 		return (WALK_DONE);
166 	}
167 	wsp->walk_addr += sizeof (entry);
168 	wsp->walk_data = (void *)(number + 1);
169 
170 	if (SM_DEBUG_DECODE(entry)) {
171 		mdb_printf("DEBUG: %3u  %10s: txg=%llu  pass=%llu\n",
172 		    number,
173 		    ddata[SM_DEBUG_ACTION_DECODE(entry)],
174 		    SM_DEBUG_TXG_DECODE(entry),
175 		    SM_DEBUG_SYNCPASS_DECODE(entry));
176 	} else {
177 		mdb_printf("Entry: %3u  offsets=%08llx-%08llx  type=%c  "
178 		    "size=%06llx", number,
179 		    SM_OFFSET_DECODE(entry) << mapshift,
180 		    (SM_OFFSET_DECODE(entry) + SM_RUN_DECODE(entry)) <<
181 		    mapshift,
182 		    SM_TYPE_DECODE(entry) == SM_ALLOC ? 'A' : 'F',
183 		    SM_RUN_DECODE(entry) << mapshift);
184 		if (verbose)
185 			mdb_printf("      (raw=%012llx)\n", entry);
186 		mdb_printf("\n");
187 	}
188 	return (WALK_NEXT);
189 }
190 
191 
192 static int
193 dataset_name(uintptr_t addr, char *buf)
194 {
195 	static int gotid;
196 	static mdb_ctf_id_t dd_id;
197 	uintptr_t dd_parent;
198 	char dd_myname[MAXNAMELEN];
199 
200 	if (!gotid) {
201 		if (mdb_ctf_lookup_by_name("struct dsl_dir",
202 		    &dd_id) == -1) {
203 			mdb_warn("couldn't find struct dsl_dir");
204 			return (DCMD_ERR);
205 		}
206 		gotid = TRUE;
207 	}
208 	if (GETMEMBID(addr, &dd_id, dd_parent, dd_parent) ||
209 	    GETMEMBID(addr, &dd_id, dd_myname, dd_myname)) {
210 		return (DCMD_ERR);
211 	}
212 
213 	if (dd_parent) {
214 		if (dataset_name(dd_parent, buf))
215 			return (DCMD_ERR);
216 		strcat(buf, "/");
217 	}
218 
219 	if (dd_myname[0])
220 		strcat(buf, dd_myname);
221 	else
222 		strcat(buf, "???");
223 
224 	return (0);
225 }
226 
227 static int
228 objset_name(uintptr_t addr, char *buf)
229 {
230 	static int gotid;
231 	static mdb_ctf_id_t os_id, ds_id;
232 	uintptr_t os_dsl_dataset;
233 	char ds_snapname[MAXNAMELEN];
234 	uintptr_t ds_dir;
235 
236 	buf[0] = '\0';
237 
238 	if (!gotid) {
239 		if (mdb_ctf_lookup_by_name("struct objset",
240 		    &os_id) == -1) {
241 			mdb_warn("couldn't find struct objset");
242 			return (DCMD_ERR);
243 		}
244 		if (mdb_ctf_lookup_by_name("struct dsl_dataset",
245 		    &ds_id) == -1) {
246 			mdb_warn("couldn't find struct dsl_dataset");
247 			return (DCMD_ERR);
248 		}
249 
250 		gotid = TRUE;
251 	}
252 
253 	if (GETMEMBID(addr, &os_id, os_dsl_dataset, os_dsl_dataset))
254 		return (DCMD_ERR);
255 
256 	if (os_dsl_dataset == 0) {
257 		strcat(buf, "mos");
258 		return (0);
259 	}
260 
261 	if (GETMEMBID(os_dsl_dataset, &ds_id, ds_snapname, ds_snapname) ||
262 	    GETMEMBID(os_dsl_dataset, &ds_id, ds_dir, ds_dir)) {
263 		return (DCMD_ERR);
264 	}
265 
266 	if (ds_dir && dataset_name(ds_dir, buf))
267 		return (DCMD_ERR);
268 
269 	if (ds_snapname[0]) {
270 		strcat(buf, "@");
271 		strcat(buf, ds_snapname);
272 	}
273 	return (0);
274 }
275 
276 static void
277 enum_lookup(char *out, size_t size, mdb_ctf_id_t id, int val,
278     const char *prefix)
279 {
280 	const char *cp;
281 	size_t len = strlen(prefix);
282 
283 	if ((cp = mdb_ctf_enum_name(id, val)) != NULL) {
284 		if (strncmp(cp, prefix, len) == 0)
285 			cp += len;
286 		(void) strncpy(out, cp, size);
287 	} else {
288 		mdb_snprintf(out, size, "? (%d)", val);
289 	}
290 }
291 
292 /* ARGSUSED */
293 static int
294 zfs_params(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
295 {
296 	/*
297 	 * This table can be approximately generated by running:
298 	 * egrep "^[a-z0-9_]+ [a-z0-9_]+( =.*)?;" *.c | cut -d ' ' -f 2
299 	 */
300 	static const char *params[] = {
301 		"arc_reduce_dnlc_percent",
302 		"zfs_arc_max",
303 		"zfs_arc_min",
304 		"arc_shrink_shift",
305 		"zfs_mdcomp_disable",
306 		"zfs_prefetch_disable",
307 		"zfetch_max_streams",
308 		"zfetch_min_sec_reap",
309 		"zfetch_block_cap",
310 		"zfetch_array_rd_sz",
311 		"zfs_default_bs",
312 		"zfs_default_ibs",
313 		"metaslab_aliquot",
314 		"reference_tracking_enable",
315 		"reference_history",
316 		"spa_max_replication_override",
317 		"spa_mode_global",
318 		"zfs_flags",
319 		"zfs_txg_synctime_ms",
320 		"zfs_txg_timeout",
321 		"zfs_write_limit_min",
322 		"zfs_write_limit_max",
323 		"zfs_write_limit_shift",
324 		"zfs_write_limit_override",
325 		"zfs_no_write_throttle",
326 		"zfs_vdev_cache_max",
327 		"zfs_vdev_cache_size",
328 		"zfs_vdev_cache_bshift",
329 		"vdev_mirror_shift",
330 		"zfs_vdev_max_pending",
331 		"zfs_vdev_min_pending",
332 		"zfs_scrub_limit",
333 		"zfs_no_scrub_io",
334 		"zfs_no_scrub_prefetch",
335 		"zfs_vdev_time_shift",
336 		"zfs_vdev_ramp_rate",
337 		"zfs_vdev_aggregation_limit",
338 		"fzap_default_block_shift",
339 		"zfs_immediate_write_sz",
340 		"zfs_read_chunk_size",
341 		"zfs_nocacheflush",
342 		"zil_replay_disable",
343 		"metaslab_gang_bang",
344 		"metaslab_df_alloc_threshold",
345 		"metaslab_df_free_pct",
346 		"zio_injection_enabled",
347 		"zvol_immediate_write_sz",
348 	};
349 
350 	for (int i = 0; i < sizeof (params) / sizeof (params[0]); i++) {
351 		int sz;
352 		uint64_t val64;
353 		uint32_t *val32p = (uint32_t *)&val64;
354 
355 		sz = mdb_readvar(&val64, params[i]);
356 		if (sz == 4) {
357 			mdb_printf("%s = 0x%x\n", params[i], *val32p);
358 		} else if (sz == 8) {
359 			mdb_printf("%s = 0x%llx\n", params[i], val64);
360 		} else {
361 			mdb_warn("variable %s not found", params[i]);
362 		}
363 	}
364 
365 	return (DCMD_OK);
366 }
367 
368 /* ARGSUSED */
369 static int
370 blkptr(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
371 {
372 	mdb_ctf_id_t type_enum, checksum_enum, compress_enum;
373 	char type[80], checksum[80], compress[80];
374 	blkptr_t blk, *bp = &blk;
375 	char buf[BP_SPRINTF_LEN];
376 
377 	if (mdb_vread(&blk, sizeof (blkptr_t), addr) == -1) {
378 		mdb_warn("failed to read blkptr_t");
379 		return (DCMD_ERR);
380 	}
381 
382 	if (mdb_ctf_lookup_by_name("enum dmu_object_type", &type_enum) == -1 ||
383 	    mdb_ctf_lookup_by_name("enum zio_checksum", &checksum_enum) == -1 ||
384 	    mdb_ctf_lookup_by_name("enum zio_compress", &compress_enum) == -1) {
385 		mdb_warn("Could not find blkptr enumerated types");
386 		return (DCMD_ERR);
387 	}
388 
389 	enum_lookup(type, sizeof (type), type_enum,
390 	    BP_GET_TYPE(bp), "DMU_OT_");
391 	enum_lookup(checksum, sizeof (checksum), checksum_enum,
392 	    BP_GET_CHECKSUM(bp), "ZIO_CHECKSUM_");
393 	enum_lookup(compress, sizeof (compress), compress_enum,
394 	    BP_GET_COMPRESS(bp), "ZIO_COMPRESS_");
395 
396 	SPRINTF_BLKPTR(mdb_snprintf, '\n', buf, bp, type, checksum, compress);
397 
398 	mdb_printf("%s\n", buf);
399 
400 	return (DCMD_OK);
401 }
402 
403 /* ARGSUSED */
404 static int
405 dbuf(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
406 {
407 	mdb_ctf_id_t id;
408 	dmu_buf_t db;
409 	uintptr_t objset;
410 	uint8_t level;
411 	uint64_t blkid;
412 	uint64_t holds;
413 	char objectname[32];
414 	char blkidname[32];
415 	char path[MAXNAMELEN];
416 
417 	if (DCMD_HDRSPEC(flags)) {
418 		mdb_printf("        addr object lvl blkid holds os\n");
419 	}
420 
421 	if (mdb_ctf_lookup_by_name("struct dmu_buf_impl", &id) == -1) {
422 		mdb_warn("couldn't find struct dmu_buf_impl_t");
423 		return (DCMD_ERR);
424 	}
425 
426 	if (GETMEMBID(addr, &id, db_objset, objset) ||
427 	    GETMEMBID(addr, &id, db, db) ||
428 	    GETMEMBID(addr, &id, db_level, level) ||
429 	    GETMEMBID(addr, &id, db_blkid, blkid)) {
430 		return (WALK_ERR);
431 	}
432 
433 	if (getrefcount(addr, &id, "db_holds", &holds)) {
434 		return (WALK_ERR);
435 	}
436 
437 	if (db.db_object == DMU_META_DNODE_OBJECT)
438 		(void) strcpy(objectname, "mdn");
439 	else
440 		(void) mdb_snprintf(objectname, sizeof (objectname), "%llx",
441 		    (u_longlong_t)db.db_object);
442 
443 	if (blkid == DMU_BONUS_BLKID)
444 		(void) strcpy(blkidname, "bonus");
445 	else
446 		(void) mdb_snprintf(blkidname, sizeof (blkidname), "%llx",
447 		    (u_longlong_t)blkid);
448 
449 	if (objset_name(objset, path)) {
450 		return (WALK_ERR);
451 	}
452 
453 	mdb_printf("%p %8s %1u %9s %2llu %s\n",
454 	    addr, objectname, level, blkidname, holds, path);
455 
456 	return (DCMD_OK);
457 }
458 
459 /* ARGSUSED */
460 static int
461 dbuf_stats(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
462 {
463 #define	HISTOSZ 32
464 	uintptr_t dbp;
465 	dmu_buf_impl_t db;
466 	dbuf_hash_table_t ht;
467 	uint64_t bucket, ndbufs;
468 	uint64_t histo[HISTOSZ];
469 	uint64_t histo2[HISTOSZ];
470 	int i, maxidx;
471 
472 	if (mdb_readvar(&ht, "dbuf_hash_table") == -1) {
473 		mdb_warn("failed to read 'dbuf_hash_table'");
474 		return (DCMD_ERR);
475 	}
476 
477 	for (i = 0; i < HISTOSZ; i++) {
478 		histo[i] = 0;
479 		histo2[i] = 0;
480 	}
481 
482 	ndbufs = 0;
483 	for (bucket = 0; bucket < ht.hash_table_mask+1; bucket++) {
484 		int len;
485 
486 		if (mdb_vread(&dbp, sizeof (void *),
487 		    (uintptr_t)(ht.hash_table+bucket)) == -1) {
488 			mdb_warn("failed to read hash bucket %u at %p",
489 			    bucket, ht.hash_table+bucket);
490 			return (DCMD_ERR);
491 		}
492 
493 		len = 0;
494 		while (dbp != 0) {
495 			if (mdb_vread(&db, sizeof (dmu_buf_impl_t),
496 			    dbp) == -1) {
497 				mdb_warn("failed to read dbuf at %p", dbp);
498 				return (DCMD_ERR);
499 			}
500 			dbp = (uintptr_t)db.db_hash_next;
501 			for (i = MIN(len, HISTOSZ - 1); i >= 0; i--)
502 				histo2[i]++;
503 			len++;
504 			ndbufs++;
505 		}
506 
507 		if (len >= HISTOSZ)
508 			len = HISTOSZ-1;
509 		histo[len]++;
510 	}
511 
512 	mdb_printf("hash table has %llu buckets, %llu dbufs "
513 	    "(avg %llu buckets/dbuf)\n",
514 	    ht.hash_table_mask+1, ndbufs,
515 	    (ht.hash_table_mask+1)/ndbufs);
516 
517 	mdb_printf("\n");
518 	maxidx = 0;
519 	for (i = 0; i < HISTOSZ; i++)
520 		if (histo[i] > 0)
521 			maxidx = i;
522 	mdb_printf("hash chain length	number of buckets\n");
523 	for (i = 0; i <= maxidx; i++)
524 		mdb_printf("%u			%llu\n", i, histo[i]);
525 
526 	mdb_printf("\n");
527 	maxidx = 0;
528 	for (i = 0; i < HISTOSZ; i++)
529 		if (histo2[i] > 0)
530 			maxidx = i;
531 	mdb_printf("hash chain depth	number of dbufs\n");
532 	for (i = 0; i <= maxidx; i++)
533 		mdb_printf("%u or more		%llu	%llu%%\n",
534 		    i, histo2[i], histo2[i]*100/ndbufs);
535 
536 
537 	return (DCMD_OK);
538 }
539 
540 #define	CHAIN_END 0xffff
541 /*
542  * ::zap_leaf [-v]
543  *
544  * Print a zap_leaf_phys_t, assumed to be 16k
545  */
546 /* ARGSUSED */
547 static int
548 zap_leaf(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
549 {
550 	char buf[16*1024];
551 	int verbose = B_FALSE;
552 	int four = B_FALSE;
553 	zap_leaf_t l;
554 	zap_leaf_phys_t *zlp = (void *)buf;
555 	int i;
556 
557 	if (mdb_getopts(argc, argv,
558 	    'v', MDB_OPT_SETBITS, TRUE, &verbose,
559 	    '4', MDB_OPT_SETBITS, TRUE, &four,
560 	    NULL) != argc)
561 		return (DCMD_USAGE);
562 
563 	l.l_phys = zlp;
564 	l.l_bs = 14; /* assume 16k blocks */
565 	if (four)
566 		l.l_bs = 12;
567 
568 	if (!(flags & DCMD_ADDRSPEC)) {
569 		return (DCMD_USAGE);
570 	}
571 
572 	if (mdb_vread(buf, sizeof (buf), addr) == -1) {
573 		mdb_warn("failed to read zap_leaf_phys_t at %p", addr);
574 		return (DCMD_ERR);
575 	}
576 
577 	if (zlp->l_hdr.lh_block_type != ZBT_LEAF ||
578 	    zlp->l_hdr.lh_magic != ZAP_LEAF_MAGIC) {
579 		mdb_warn("This does not appear to be a zap_leaf_phys_t");
580 		return (DCMD_ERR);
581 	}
582 
583 	mdb_printf("zap_leaf_phys_t at %p:\n", addr);
584 	mdb_printf("    lh_prefix_len = %u\n", zlp->l_hdr.lh_prefix_len);
585 	mdb_printf("    lh_prefix = %llx\n", zlp->l_hdr.lh_prefix);
586 	mdb_printf("    lh_nentries = %u\n", zlp->l_hdr.lh_nentries);
587 	mdb_printf("    lh_nfree = %u\n", zlp->l_hdr.lh_nfree,
588 	    zlp->l_hdr.lh_nfree * 100 / (ZAP_LEAF_NUMCHUNKS(&l)));
589 	mdb_printf("    lh_freelist = %u\n", zlp->l_hdr.lh_freelist);
590 	mdb_printf("    lh_flags = %x (%s)\n", zlp->l_hdr.lh_flags,
591 	    zlp->l_hdr.lh_flags & ZLF_ENTRIES_CDSORTED ?
592 	    "ENTRIES_CDSORTED" : "");
593 
594 	if (verbose) {
595 		mdb_printf(" hash table:\n");
596 		for (i = 0; i < ZAP_LEAF_HASH_NUMENTRIES(&l); i++) {
597 			if (zlp->l_hash[i] != CHAIN_END)
598 				mdb_printf("    %u: %u\n", i, zlp->l_hash[i]);
599 		}
600 	}
601 
602 	mdb_printf(" chunks:\n");
603 	for (i = 0; i < ZAP_LEAF_NUMCHUNKS(&l); i++) {
604 		/* LINTED: alignment */
605 		zap_leaf_chunk_t *zlc = &ZAP_LEAF_CHUNK(&l, i);
606 		switch (zlc->l_entry.le_type) {
607 		case ZAP_CHUNK_FREE:
608 			if (verbose) {
609 				mdb_printf("    %u: free; lf_next = %u\n",
610 				    i, zlc->l_free.lf_next);
611 			}
612 			break;
613 		case ZAP_CHUNK_ENTRY:
614 			mdb_printf("    %u: entry\n", i);
615 			if (verbose) {
616 				mdb_printf("        le_next = %u\n",
617 				    zlc->l_entry.le_next);
618 			}
619 			mdb_printf("        le_name_chunk = %u\n",
620 			    zlc->l_entry.le_name_chunk);
621 			mdb_printf("        le_name_numints = %u\n",
622 			    zlc->l_entry.le_name_numints);
623 			mdb_printf("        le_value_chunk = %u\n",
624 			    zlc->l_entry.le_value_chunk);
625 			mdb_printf("        le_value_intlen = %u\n",
626 			    zlc->l_entry.le_value_intlen);
627 			mdb_printf("        le_value_numints = %u\n",
628 			    zlc->l_entry.le_value_numints);
629 			mdb_printf("        le_cd = %u\n",
630 			    zlc->l_entry.le_cd);
631 			mdb_printf("        le_hash = %llx\n",
632 			    zlc->l_entry.le_hash);
633 			break;
634 		case ZAP_CHUNK_ARRAY:
635 			mdb_printf("    %u: array", i);
636 			if (strisprint((char *)zlc->l_array.la_array))
637 				mdb_printf(" \"%s\"", zlc->l_array.la_array);
638 			mdb_printf("\n");
639 			if (verbose) {
640 				int j;
641 				mdb_printf("        ");
642 				for (j = 0; j < ZAP_LEAF_ARRAY_BYTES; j++) {
643 					mdb_printf("%02x ",
644 					    zlc->l_array.la_array[j]);
645 				}
646 				mdb_printf("\n");
647 			}
648 			if (zlc->l_array.la_next != CHAIN_END) {
649 				mdb_printf("        lf_next = %u\n",
650 				    zlc->l_array.la_next);
651 			}
652 			break;
653 		default:
654 			mdb_printf("    %u: undefined type %u\n",
655 			    zlc->l_entry.le_type);
656 		}
657 	}
658 
659 	return (DCMD_OK);
660 }
661 
662 typedef struct dbufs_data {
663 	mdb_ctf_id_t id;
664 	uint64_t objset;
665 	uint64_t object;
666 	uint64_t level;
667 	uint64_t blkid;
668 	char *osname;
669 } dbufs_data_t;
670 
671 #define	DBUFS_UNSET	(0xbaddcafedeadbeefULL)
672 
673 /* ARGSUSED */
674 static int
675 dbufs_cb(uintptr_t addr, const void *unknown, void *arg)
676 {
677 	dbufs_data_t *data = arg;
678 	uintptr_t objset;
679 	dmu_buf_t db;
680 	uint8_t level;
681 	uint64_t blkid;
682 	char osname[MAXNAMELEN];
683 
684 	if (GETMEMBID(addr, &data->id, db_objset, objset) ||
685 	    GETMEMBID(addr, &data->id, db, db) ||
686 	    GETMEMBID(addr, &data->id, db_level, level) ||
687 	    GETMEMBID(addr, &data->id, db_blkid, blkid)) {
688 		return (WALK_ERR);
689 	}
690 
691 	if ((data->objset == DBUFS_UNSET || data->objset == objset) &&
692 	    (data->osname == NULL || (objset_name(objset, osname) == 0 &&
693 	    strcmp(data->osname, osname) == 0)) &&
694 	    (data->object == DBUFS_UNSET || data->object == db.db_object) &&
695 	    (data->level == DBUFS_UNSET || data->level == level) &&
696 	    (data->blkid == DBUFS_UNSET || data->blkid == blkid)) {
697 		mdb_printf("%#lr\n", addr);
698 	}
699 	return (WALK_NEXT);
700 }
701 
702 /* ARGSUSED */
703 static int
704 dbufs(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
705 {
706 	dbufs_data_t data;
707 	char *object = NULL;
708 	char *blkid = NULL;
709 
710 	data.objset = data.object = data.level = data.blkid = DBUFS_UNSET;
711 	data.osname = NULL;
712 
713 	if (mdb_getopts(argc, argv,
714 	    'O', MDB_OPT_UINT64, &data.objset,
715 	    'n', MDB_OPT_STR, &data.osname,
716 	    'o', MDB_OPT_STR, &object,
717 	    'l', MDB_OPT_UINT64, &data.level,
718 	    'b', MDB_OPT_STR, &blkid) != argc) {
719 		return (DCMD_USAGE);
720 	}
721 
722 	if (object) {
723 		if (strcmp(object, "mdn") == 0) {
724 			data.object = DMU_META_DNODE_OBJECT;
725 		} else {
726 			data.object = mdb_strtoull(object);
727 		}
728 	}
729 
730 	if (blkid) {
731 		if (strcmp(blkid, "bonus") == 0) {
732 			data.blkid = DMU_BONUS_BLKID;
733 		} else {
734 			data.blkid = mdb_strtoull(blkid);
735 		}
736 	}
737 
738 	if (mdb_ctf_lookup_by_name("struct dmu_buf_impl", &data.id) == -1) {
739 		mdb_warn("couldn't find struct dmu_buf_impl_t");
740 		return (DCMD_ERR);
741 	}
742 
743 	if (mdb_walk("dmu_buf_impl_t", dbufs_cb, &data) != 0) {
744 		mdb_warn("can't walk dbufs");
745 		return (DCMD_ERR);
746 	}
747 
748 	return (DCMD_OK);
749 }
750 
751 typedef struct abuf_find_data {
752 	dva_t dva;
753 	mdb_ctf_id_t id;
754 } abuf_find_data_t;
755 
756 /* ARGSUSED */
757 static int
758 abuf_find_cb(uintptr_t addr, const void *unknown, void *arg)
759 {
760 	abuf_find_data_t *data = arg;
761 	dva_t dva;
762 
763 	if (GETMEMBID(addr, &data->id, b_dva, dva)) {
764 		return (WALK_ERR);
765 	}
766 
767 	if (dva.dva_word[0] == data->dva.dva_word[0] &&
768 	    dva.dva_word[1] == data->dva.dva_word[1]) {
769 		mdb_printf("%#lr\n", addr);
770 	}
771 	return (WALK_NEXT);
772 }
773 
774 /* ARGSUSED */
775 static int
776 abuf_find(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
777 {
778 	abuf_find_data_t data;
779 	GElf_Sym sym;
780 	int i;
781 	const char *syms[] = {
782 		"ARC_mru",
783 		"ARC_mru_ghost",
784 		"ARC_mfu",
785 		"ARC_mfu_ghost",
786 	};
787 
788 	if (argc != 2)
789 		return (DCMD_USAGE);
790 
791 	for (i = 0; i < 2; i ++) {
792 		switch (argv[i].a_type) {
793 		case MDB_TYPE_STRING:
794 			data.dva.dva_word[i] = mdb_strtoull(argv[i].a_un.a_str);
795 			break;
796 		case MDB_TYPE_IMMEDIATE:
797 			data.dva.dva_word[i] = argv[i].a_un.a_val;
798 			break;
799 		default:
800 			return (DCMD_USAGE);
801 		}
802 	}
803 
804 	if (mdb_ctf_lookup_by_name("struct arc_buf_hdr", &data.id) == -1) {
805 		mdb_warn("couldn't find struct arc_buf_hdr");
806 		return (DCMD_ERR);
807 	}
808 
809 	for (i = 0; i < sizeof (syms) / sizeof (syms[0]); i++) {
810 		if (mdb_lookup_by_name(syms[i], &sym)) {
811 			mdb_warn("can't find symbol %s", syms[i]);
812 			return (DCMD_ERR);
813 		}
814 
815 		if (mdb_pwalk("list", abuf_find_cb, &data, sym.st_value) != 0) {
816 			mdb_warn("can't walk %s", syms[i]);
817 			return (DCMD_ERR);
818 		}
819 	}
820 
821 	return (DCMD_OK);
822 }
823 
824 /* ARGSUSED */
825 static int
826 dbgmsg_cb(uintptr_t addr, const void *unknown, void *arg)
827 {
828 	static mdb_ctf_id_t id;
829 	static boolean_t gotid;
830 	static ulong_t off;
831 
832 	int *verbosep = arg;
833 	time_t timestamp;
834 	char buf[1024];
835 
836 	if (!gotid) {
837 		if (mdb_ctf_lookup_by_name("struct zfs_dbgmsg", &id) == -1) {
838 			mdb_warn("couldn't find struct zfs_dbgmsg");
839 			return (WALK_ERR);
840 		}
841 		gotid = TRUE;
842 		if (mdb_ctf_offsetof(id, "zdm_msg", &off) == -1) {
843 			mdb_warn("couldn't find zdm_msg");
844 			return (WALK_ERR);
845 		}
846 		off /= 8;
847 	}
848 
849 
850 	if (GETMEMBID(addr, &id, zdm_timestamp, timestamp)) {
851 		return (WALK_ERR);
852 	}
853 
854 	if (mdb_readstr(buf, sizeof (buf), addr + off) == -1) {
855 		mdb_warn("failed to read zdm_msg at %p\n", addr + off);
856 		return (DCMD_ERR);
857 	}
858 
859 	if (*verbosep)
860 		mdb_printf("%Y ", timestamp);
861 
862 	mdb_printf("%s\n", buf);
863 
864 	if (*verbosep)
865 		(void) mdb_call_dcmd("whatis", addr, DCMD_ADDRSPEC, 0, NULL);
866 
867 	return (WALK_NEXT);
868 }
869 
870 /* ARGSUSED */
871 static int
872 dbgmsg(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
873 {
874 	GElf_Sym sym;
875 	int verbose = FALSE;
876 
877 	if (mdb_getopts(argc, argv,
878 	    'v', MDB_OPT_SETBITS, TRUE, &verbose,
879 	    NULL) != argc)
880 		return (DCMD_USAGE);
881 
882 	if (mdb_lookup_by_name("zfs_dbgmsgs", &sym)) {
883 		mdb_warn("can't find zfs_dbgmsgs");
884 		return (DCMD_ERR);
885 	}
886 
887 	if (mdb_pwalk("list", dbgmsg_cb, &verbose, sym.st_value) != 0) {
888 		mdb_warn("can't walk zfs_dbgmsgs");
889 		return (DCMD_ERR);
890 	}
891 
892 	return (DCMD_OK);
893 }
894 
895 /*ARGSUSED*/
896 static int
897 arc_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
898 {
899 	kstat_named_t *stats;
900 	GElf_Sym sym;
901 	int nstats, i;
902 	uint_t opt_a = FALSE;
903 	uint_t opt_b = FALSE;
904 	uint_t shift = 0;
905 	const char *suffix;
906 
907 	static const char *bytestats[] = {
908 		"p", "c", "c_min", "c_max", "size", NULL
909 	};
910 
911 	static const char *extras[] = {
912 		"arc_no_grow", "arc_tempreserve",
913 		"arc_meta_used", "arc_meta_limit", "arc_meta_max",
914 		NULL
915 	};
916 
917 	if (mdb_lookup_by_name("arc_stats", &sym) == -1) {
918 		mdb_warn("failed to find 'arc_stats'");
919 		return (DCMD_ERR);
920 	}
921 
922 	stats = mdb_zalloc(sym.st_size, UM_SLEEP | UM_GC);
923 
924 	if (mdb_vread(stats, sym.st_size, sym.st_value) == -1) {
925 		mdb_warn("couldn't read 'arc_stats' at %p", sym.st_value);
926 		return (DCMD_ERR);
927 	}
928 
929 	nstats = sym.st_size / sizeof (kstat_named_t);
930 
931 	/* NB: -a / opt_a are ignored for backwards compatability */
932 	if (mdb_getopts(argc, argv,
933 	    'a', MDB_OPT_SETBITS, TRUE, &opt_a,
934 	    'b', MDB_OPT_SETBITS, TRUE, &opt_b,
935 	    'k', MDB_OPT_SETBITS, 10, &shift,
936 	    'm', MDB_OPT_SETBITS, 20, &shift,
937 	    'g', MDB_OPT_SETBITS, 30, &shift,
938 	    NULL) != argc)
939 		return (DCMD_USAGE);
940 
941 	if (!opt_b && !shift)
942 		shift = 20;
943 
944 	switch (shift) {
945 	case 0:
946 		suffix = "B";
947 		break;
948 	case 10:
949 		suffix = "KB";
950 		break;
951 	case 20:
952 		suffix = "MB";
953 		break;
954 	case 30:
955 		suffix = "GB";
956 		break;
957 	default:
958 		suffix = "XX";
959 	}
960 
961 	for (i = 0; i < nstats; i++) {
962 		int j;
963 		boolean_t bytes = B_FALSE;
964 
965 		for (j = 0; bytestats[j]; j++) {
966 			if (strcmp(stats[i].name, bytestats[j]) == 0) {
967 				bytes = B_TRUE;
968 				break;
969 			}
970 		}
971 
972 		if (bytes) {
973 			mdb_printf("%-25s = %9llu %s\n", stats[i].name,
974 			    stats[i].value.ui64 >> shift, suffix);
975 		} else {
976 			mdb_printf("%-25s = %9llu\n", stats[i].name,
977 			    stats[i].value.ui64);
978 		}
979 	}
980 
981 	for (i = 0; extras[i]; i++) {
982 		uint64_t buf;
983 
984 		if (mdb_lookup_by_name(extras[i], &sym) == -1) {
985 			mdb_warn("failed to find '%s'", extras[i]);
986 			return (DCMD_ERR);
987 		}
988 
989 		if (sym.st_size != sizeof (uint64_t) &&
990 		    sym.st_size != sizeof (uint32_t)) {
991 			mdb_warn("expected scalar for variable '%s'\n",
992 			    extras[i]);
993 			return (DCMD_ERR);
994 		}
995 
996 		if (mdb_vread(&buf, sym.st_size, sym.st_value) == -1) {
997 			mdb_warn("couldn't read '%s'", extras[i]);
998 			return (DCMD_ERR);
999 		}
1000 
1001 		mdb_printf("%-25s = ", extras[i]);
1002 
1003 		/* NB: all the 64-bit extras happen to be byte counts */
1004 		if (sym.st_size == sizeof (uint64_t))
1005 			mdb_printf("%9llu %s\n", buf >> shift, suffix);
1006 
1007 		if (sym.st_size == sizeof (uint32_t))
1008 			mdb_printf("%9d\n", *((uint32_t *)&buf));
1009 	}
1010 	return (DCMD_OK);
1011 }
1012 
1013 /*
1014  * ::spa
1015  *
1016  * 	-c	Print configuration information as well
1017  * 	-v	Print vdev state
1018  * 	-e	Print vdev error stats
1019  *
1020  * Print a summarized spa_t.  When given no arguments, prints out a table of all
1021  * active pools on the system.
1022  */
1023 /* ARGSUSED */
1024 static int
1025 spa_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1026 {
1027 	spa_t spa;
1028 	const char *statetab[] = { "ACTIVE", "EXPORTED", "DESTROYED",
1029 		"SPARE", "L2CACHE", "UNINIT", "UNAVAIL", "POTENTIAL" };
1030 	const char *state;
1031 	int config = FALSE;
1032 	int vdevs = FALSE;
1033 	int errors = FALSE;
1034 
1035 	if (mdb_getopts(argc, argv,
1036 	    'c', MDB_OPT_SETBITS, TRUE, &config,
1037 	    'v', MDB_OPT_SETBITS, TRUE, &vdevs,
1038 	    'e', MDB_OPT_SETBITS, TRUE, &errors,
1039 	    NULL) != argc)
1040 		return (DCMD_USAGE);
1041 
1042 	if (!(flags & DCMD_ADDRSPEC)) {
1043 		if (mdb_walk_dcmd("spa", "spa", argc, argv) == -1) {
1044 			mdb_warn("can't walk spa");
1045 			return (DCMD_ERR);
1046 		}
1047 
1048 		return (DCMD_OK);
1049 	}
1050 
1051 	if (flags & DCMD_PIPE_OUT) {
1052 		mdb_printf("%#lr\n", addr);
1053 		return (DCMD_OK);
1054 	}
1055 
1056 	if (DCMD_HDRSPEC(flags))
1057 		mdb_printf("%<u>%-?s %9s %-*s%</u>\n", "ADDR", "STATE",
1058 		    sizeof (uintptr_t) == 4 ? 60 : 52, "NAME");
1059 
1060 	if (mdb_vread(&spa, sizeof (spa), addr) == -1) {
1061 		mdb_warn("failed to read spa_t at %p", addr);
1062 		return (DCMD_ERR);
1063 	}
1064 
1065 	if (spa.spa_state < 0 || spa.spa_state > POOL_STATE_UNAVAIL)
1066 		state = "UNKNOWN";
1067 	else
1068 		state = statetab[spa.spa_state];
1069 
1070 	mdb_printf("%0?p %9s %s\n", addr, state, spa.spa_name);
1071 
1072 	if (config) {
1073 		mdb_printf("\n");
1074 		mdb_inc_indent(4);
1075 		if (mdb_call_dcmd("spa_config", addr, flags, 0,
1076 		    NULL) != DCMD_OK)
1077 			return (DCMD_ERR);
1078 		mdb_dec_indent(4);
1079 	}
1080 
1081 	if (vdevs || errors) {
1082 		mdb_arg_t v;
1083 
1084 		v.a_type = MDB_TYPE_STRING;
1085 		v.a_un.a_str = "-e";
1086 
1087 		mdb_printf("\n");
1088 		mdb_inc_indent(4);
1089 		if (mdb_call_dcmd("spa_vdevs", addr, flags, errors ? 1 : 0,
1090 		    &v) != DCMD_OK)
1091 			return (DCMD_ERR);
1092 		mdb_dec_indent(4);
1093 	}
1094 
1095 	return (DCMD_OK);
1096 }
1097 
1098 /*
1099  * ::spa_config
1100  *
1101  * Given a spa_t, print the configuration information stored in spa_config.
1102  * Since it's just an nvlist, format it as an indented list of name=value pairs.
1103  * We simply read the value of spa_config and pass off to ::nvlist.
1104  */
1105 /* ARGSUSED */
1106 static int
1107 spa_print_config(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1108 {
1109 	spa_t spa;
1110 
1111 	if (argc != 0 || !(flags & DCMD_ADDRSPEC))
1112 		return (DCMD_USAGE);
1113 
1114 	if (mdb_vread(&spa, sizeof (spa), addr) == -1) {
1115 		mdb_warn("failed to read spa_t at %p", addr);
1116 		return (DCMD_ERR);
1117 	}
1118 
1119 	if (spa.spa_config == NULL) {
1120 		mdb_printf("(none)\n");
1121 		return (DCMD_OK);
1122 	}
1123 
1124 	return (mdb_call_dcmd("nvlist", (uintptr_t)spa.spa_config, flags,
1125 	    0, NULL));
1126 }
1127 
1128 /*
1129  * ::vdev
1130  *
1131  * Print out a summarized vdev_t, in the following form:
1132  *
1133  * ADDR             STATE	AUX            DESC
1134  * fffffffbcde23df0 HEALTHY	-              /dev/dsk/c0t0d0
1135  *
1136  * If '-r' is specified, recursively visit all children.
1137  *
1138  * With '-e', the statistics associated with the vdev are printed as well.
1139  */
1140 static int
1141 do_print_vdev(uintptr_t addr, int flags, int depth, int stats,
1142     int recursive)
1143 {
1144 	vdev_t vdev;
1145 	char desc[MAXNAMELEN];
1146 	int c, children;
1147 	uintptr_t *child;
1148 	const char *state, *aux;
1149 
1150 	if (mdb_vread(&vdev, sizeof (vdev), (uintptr_t)addr) == -1) {
1151 		mdb_warn("failed to read vdev_t at %p\n", (uintptr_t)addr);
1152 		return (DCMD_ERR);
1153 	}
1154 
1155 	if (flags & DCMD_PIPE_OUT) {
1156 		mdb_printf("%#lr", addr);
1157 	} else {
1158 		if (vdev.vdev_path != NULL) {
1159 			if (mdb_readstr(desc, sizeof (desc),
1160 			    (uintptr_t)vdev.vdev_path) == -1) {
1161 				mdb_warn("failed to read vdev_path at %p\n",
1162 				    vdev.vdev_path);
1163 				return (DCMD_ERR);
1164 			}
1165 		} else if (vdev.vdev_ops != NULL) {
1166 			vdev_ops_t ops;
1167 			if (mdb_vread(&ops, sizeof (ops),
1168 			    (uintptr_t)vdev.vdev_ops) == -1) {
1169 				mdb_warn("failed to read vdev_ops at %p\n",
1170 				    vdev.vdev_ops);
1171 				return (DCMD_ERR);
1172 			}
1173 			(void) strcpy(desc, ops.vdev_op_type);
1174 		} else {
1175 			(void) strcpy(desc, "<unknown>");
1176 		}
1177 
1178 		if (depth == 0 && DCMD_HDRSPEC(flags))
1179 			mdb_printf("%<u>%-?s %-9s %-12s %-*s%</u>\n",
1180 			    "ADDR", "STATE", "AUX",
1181 			    sizeof (uintptr_t) == 4 ? 43 : 35,
1182 			    "DESCRIPTION");
1183 
1184 		mdb_printf("%0?p ", addr);
1185 
1186 		switch (vdev.vdev_state) {
1187 		case VDEV_STATE_CLOSED:
1188 			state = "CLOSED";
1189 			break;
1190 		case VDEV_STATE_OFFLINE:
1191 			state = "OFFLINE";
1192 			break;
1193 		case VDEV_STATE_CANT_OPEN:
1194 			state = "CANT_OPEN";
1195 			break;
1196 		case VDEV_STATE_DEGRADED:
1197 			state = "DEGRADED";
1198 			break;
1199 		case VDEV_STATE_HEALTHY:
1200 			state = "HEALTHY";
1201 			break;
1202 		case VDEV_STATE_REMOVED:
1203 			state = "REMOVED";
1204 			break;
1205 		case VDEV_STATE_FAULTED:
1206 			state = "FAULTED";
1207 			break;
1208 		default:
1209 			state = "UNKNOWN";
1210 			break;
1211 		}
1212 
1213 		switch (vdev.vdev_stat.vs_aux) {
1214 		case VDEV_AUX_NONE:
1215 			aux = "-";
1216 			break;
1217 		case VDEV_AUX_OPEN_FAILED:
1218 			aux = "OPEN_FAILED";
1219 			break;
1220 		case VDEV_AUX_CORRUPT_DATA:
1221 			aux = "CORRUPT_DATA";
1222 			break;
1223 		case VDEV_AUX_NO_REPLICAS:
1224 			aux = "NO_REPLICAS";
1225 			break;
1226 		case VDEV_AUX_BAD_GUID_SUM:
1227 			aux = "BAD_GUID_SUM";
1228 			break;
1229 		case VDEV_AUX_TOO_SMALL:
1230 			aux = "TOO_SMALL";
1231 			break;
1232 		case VDEV_AUX_BAD_LABEL:
1233 			aux = "BAD_LABEL";
1234 			break;
1235 		case VDEV_AUX_VERSION_NEWER:
1236 			aux = "VERS_NEWER";
1237 			break;
1238 		case VDEV_AUX_VERSION_OLDER:
1239 			aux = "VERS_OLDER";
1240 			break;
1241 		case VDEV_AUX_UNSUP_FEAT:
1242 			aux = "UNSUP_FEAT";
1243 			break;
1244 		case VDEV_AUX_SPARED:
1245 			aux = "SPARED";
1246 			break;
1247 		case VDEV_AUX_ERR_EXCEEDED:
1248 			aux = "ERR_EXCEEDED";
1249 			break;
1250 		case VDEV_AUX_IO_FAILURE:
1251 			aux = "IO_FAILURE";
1252 			break;
1253 		case VDEV_AUX_BAD_LOG:
1254 			aux = "BAD_LOG";
1255 			break;
1256 		case VDEV_AUX_EXTERNAL:
1257 			aux = "EXTERNAL";
1258 			break;
1259 		case VDEV_AUX_SPLIT_POOL:
1260 			aux = "SPLIT_POOL";
1261 			break;
1262 		default:
1263 			aux = "UNKNOWN";
1264 			break;
1265 		}
1266 
1267 		mdb_printf("%-9s %-12s %*s%s\n", state, aux, depth, "", desc);
1268 
1269 		if (stats) {
1270 			vdev_stat_t *vs = &vdev.vdev_stat;
1271 			int i;
1272 
1273 			mdb_inc_indent(4);
1274 			mdb_printf("\n");
1275 			mdb_printf("%<u>       %12s %12s %12s %12s "
1276 			    "%12s%</u>\n", "READ", "WRITE", "FREE", "CLAIM",
1277 			    "IOCTL");
1278 			mdb_printf("OPS     ");
1279 			for (i = 1; i < ZIO_TYPES; i++)
1280 				mdb_printf("%11#llx%s", vs->vs_ops[i],
1281 				    i == ZIO_TYPES - 1 ? "" : "  ");
1282 			mdb_printf("\n");
1283 			mdb_printf("BYTES   ");
1284 			for (i = 1; i < ZIO_TYPES; i++)
1285 				mdb_printf("%11#llx%s", vs->vs_bytes[i],
1286 				    i == ZIO_TYPES - 1 ? "" : "  ");
1287 
1288 
1289 			mdb_printf("\n");
1290 			mdb_printf("EREAD    %10#llx\n", vs->vs_read_errors);
1291 			mdb_printf("EWRITE   %10#llx\n", vs->vs_write_errors);
1292 			mdb_printf("ECKSUM   %10#llx\n",
1293 			    vs->vs_checksum_errors);
1294 			mdb_dec_indent(4);
1295 		}
1296 
1297 		if (stats)
1298 			mdb_printf("\n");
1299 	}
1300 
1301 	children = vdev.vdev_children;
1302 
1303 	if (children == 0 || !recursive)
1304 		return (DCMD_OK);
1305 
1306 	child = mdb_alloc(children * sizeof (void *), UM_SLEEP | UM_GC);
1307 	if (mdb_vread(child, children * sizeof (void *),
1308 	    (uintptr_t)vdev.vdev_child) == -1) {
1309 		mdb_warn("failed to read vdev children at %p", vdev.vdev_child);
1310 		return (DCMD_ERR);
1311 	}
1312 
1313 	for (c = 0; c < children; c++) {
1314 		if (do_print_vdev(child[c], flags, depth + 2, stats,
1315 		    recursive))
1316 			return (DCMD_ERR);
1317 	}
1318 
1319 	return (DCMD_OK);
1320 }
1321 
1322 static int
1323 vdev_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1324 {
1325 	int recursive = FALSE;
1326 	int stats = FALSE;
1327 	uint64_t depth = 0;
1328 
1329 	if (mdb_getopts(argc, argv,
1330 	    'r', MDB_OPT_SETBITS, TRUE, &recursive,
1331 	    'e', MDB_OPT_SETBITS, TRUE, &stats,
1332 	    'd', MDB_OPT_UINT64, &depth,
1333 	    NULL) != argc)
1334 		return (DCMD_USAGE);
1335 
1336 	if (!(flags & DCMD_ADDRSPEC)) {
1337 		mdb_warn("no vdev_t address given\n");
1338 		return (DCMD_ERR);
1339 	}
1340 
1341 	return (do_print_vdev(addr, flags, (int)depth, stats, recursive));
1342 }
1343 
1344 typedef struct metaslab_walk_data {
1345 	uint64_t mw_numvdevs;
1346 	uintptr_t *mw_vdevs;
1347 	int mw_curvdev;
1348 	uint64_t mw_nummss;
1349 	uintptr_t *mw_mss;
1350 	int mw_curms;
1351 } metaslab_walk_data_t;
1352 
1353 static int
1354 metaslab_walk_step(mdb_walk_state_t *wsp)
1355 {
1356 	metaslab_walk_data_t *mw = wsp->walk_data;
1357 	metaslab_t ms;
1358 	uintptr_t msp;
1359 
1360 	if (mw->mw_curvdev >= mw->mw_numvdevs)
1361 		return (WALK_DONE);
1362 
1363 	if (mw->mw_mss == NULL) {
1364 		uintptr_t mssp;
1365 		uintptr_t vdevp;
1366 
1367 		ASSERT(mw->mw_curms == 0);
1368 		ASSERT(mw->mw_nummss == 0);
1369 
1370 		vdevp = mw->mw_vdevs[mw->mw_curvdev];
1371 		if (GETMEMB(vdevp, struct vdev, vdev_ms, mssp) ||
1372 		    GETMEMB(vdevp, struct vdev, vdev_ms_count, mw->mw_nummss)) {
1373 			return (WALK_ERR);
1374 		}
1375 
1376 		mw->mw_mss = mdb_alloc(mw->mw_nummss * sizeof (void*),
1377 		    UM_SLEEP | UM_GC);
1378 		if (mdb_vread(mw->mw_mss, mw->mw_nummss * sizeof (void*),
1379 		    mssp) == -1) {
1380 			mdb_warn("failed to read vdev_ms at %p", mssp);
1381 			return (WALK_ERR);
1382 		}
1383 	}
1384 
1385 	if (mw->mw_curms >= mw->mw_nummss) {
1386 		mw->mw_mss = NULL;
1387 		mw->mw_curms = 0;
1388 		mw->mw_nummss = 0;
1389 		mw->mw_curvdev++;
1390 		return (WALK_NEXT);
1391 	}
1392 
1393 	msp = mw->mw_mss[mw->mw_curms];
1394 	if (mdb_vread(&ms, sizeof (metaslab_t), msp) == -1) {
1395 		mdb_warn("failed to read metaslab_t at %p", msp);
1396 		return (WALK_ERR);
1397 	}
1398 
1399 	mw->mw_curms++;
1400 
1401 	return (wsp->walk_callback(msp, &ms, wsp->walk_cbdata));
1402 }
1403 
1404 /* ARGSUSED */
1405 static int
1406 metaslab_walk_init(mdb_walk_state_t *wsp)
1407 {
1408 	metaslab_walk_data_t *mw;
1409 	uintptr_t root_vdevp;
1410 	uintptr_t childp;
1411 
1412 	if (wsp->walk_addr == NULL) {
1413 		mdb_warn("must supply address of spa_t\n");
1414 		return (WALK_ERR);
1415 	}
1416 
1417 	mw = mdb_zalloc(sizeof (metaslab_walk_data_t), UM_SLEEP | UM_GC);
1418 
1419 	if (GETMEMB(wsp->walk_addr, struct spa, spa_root_vdev, root_vdevp) ||
1420 	    GETMEMB(root_vdevp, struct vdev, vdev_children, mw->mw_numvdevs) ||
1421 	    GETMEMB(root_vdevp, struct vdev, vdev_child, childp)) {
1422 		return (DCMD_ERR);
1423 	}
1424 
1425 	mw->mw_vdevs = mdb_alloc(mw->mw_numvdevs * sizeof (void *),
1426 	    UM_SLEEP | UM_GC);
1427 	if (mdb_vread(mw->mw_vdevs, mw->mw_numvdevs * sizeof (void *),
1428 	    childp) == -1) {
1429 		mdb_warn("failed to read root vdev children at %p", childp);
1430 		return (DCMD_ERR);
1431 	}
1432 
1433 	wsp->walk_data = mw;
1434 
1435 	return (WALK_NEXT);
1436 }
1437 
1438 typedef struct mdb_spa {
1439 	uintptr_t spa_dsl_pool;
1440 	uintptr_t spa_root_vdev;
1441 } mdb_spa_t;
1442 
1443 typedef struct mdb_dsl_dir {
1444 	uintptr_t dd_phys;
1445 	int64_t dd_space_towrite[TXG_SIZE];
1446 } mdb_dsl_dir_t;
1447 
1448 typedef struct mdb_dsl_dir_phys {
1449 	uint64_t dd_used_bytes;
1450 	uint64_t dd_compressed_bytes;
1451 	uint64_t dd_uncompressed_bytes;
1452 } mdb_dsl_dir_phys_t;
1453 
1454 typedef struct mdb_vdev {
1455 	uintptr_t vdev_parent;
1456 	uintptr_t vdev_ms;
1457 	uint64_t vdev_ms_count;
1458 	vdev_stat_t vdev_stat;
1459 } mdb_vdev_t;
1460 
1461 typedef struct mdb_metaslab {
1462 	space_map_t ms_allocmap[TXG_SIZE];
1463 	space_map_t ms_freemap[TXG_SIZE];
1464 	space_map_t ms_map;
1465 	space_map_obj_t ms_smo;
1466 	space_map_obj_t ms_smo_syncing;
1467 } mdb_metaslab_t;
1468 
1469 typedef struct space_data {
1470 	uint64_t ms_allocmap[TXG_SIZE];
1471 	uint64_t ms_freemap[TXG_SIZE];
1472 	uint64_t ms_map;
1473 	uint64_t avail;
1474 	uint64_t nowavail;
1475 } space_data_t;
1476 
1477 /* ARGSUSED */
1478 static int
1479 space_cb(uintptr_t addr, const void *unknown, void *arg)
1480 {
1481 	space_data_t *sd = arg;
1482 	mdb_metaslab_t ms;
1483 
1484 	if (GETMEMB(addr, struct metaslab, ms_allocmap, ms.ms_allocmap) ||
1485 	    GETMEMB(addr, struct metaslab, ms_freemap, ms.ms_freemap) ||
1486 	    GETMEMB(addr, struct metaslab, ms_map, ms.ms_map) ||
1487 	    GETMEMB(addr, struct metaslab, ms_smo, ms.ms_smo) ||
1488 	    GETMEMB(addr, struct metaslab, ms_smo_syncing, ms.ms_smo_syncing)) {
1489 		return (WALK_ERR);
1490 	}
1491 
1492 	sd->ms_allocmap[0] += ms.ms_allocmap[0].sm_space;
1493 	sd->ms_allocmap[1] += ms.ms_allocmap[1].sm_space;
1494 	sd->ms_allocmap[2] += ms.ms_allocmap[2].sm_space;
1495 	sd->ms_allocmap[3] += ms.ms_allocmap[3].sm_space;
1496 	sd->ms_freemap[0] += ms.ms_freemap[0].sm_space;
1497 	sd->ms_freemap[1] += ms.ms_freemap[1].sm_space;
1498 	sd->ms_freemap[2] += ms.ms_freemap[2].sm_space;
1499 	sd->ms_freemap[3] += ms.ms_freemap[3].sm_space;
1500 	sd->ms_map += ms.ms_map.sm_space;
1501 	sd->avail += ms.ms_map.sm_size - ms.ms_smo.smo_alloc;
1502 	sd->nowavail += ms.ms_map.sm_size - ms.ms_smo_syncing.smo_alloc;
1503 
1504 	return (WALK_NEXT);
1505 }
1506 
1507 /*
1508  * ::spa_space [-b]
1509  *
1510  * Given a spa_t, print out it's on-disk space usage and in-core
1511  * estimates of future usage.  If -b is given, print space in bytes.
1512  * Otherwise print in megabytes.
1513  */
1514 /* ARGSUSED */
1515 static int
1516 spa_space(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1517 {
1518 	mdb_spa_t spa;
1519 	uintptr_t dp_root_dir;
1520 	mdb_dsl_dir_t dd;
1521 	mdb_dsl_dir_phys_t dsp;
1522 	uint64_t children;
1523 	uintptr_t childaddr;
1524 	space_data_t sd;
1525 	int shift = 20;
1526 	char *suffix = "M";
1527 	int bits = FALSE;
1528 
1529 	if (mdb_getopts(argc, argv, 'b', MDB_OPT_SETBITS, TRUE, &bits, NULL) !=
1530 	    argc)
1531 		return (DCMD_USAGE);
1532 	if (!(flags & DCMD_ADDRSPEC))
1533 		return (DCMD_USAGE);
1534 
1535 	if (bits) {
1536 		shift = 0;
1537 		suffix = "";
1538 	}
1539 
1540 	if (GETMEMB(addr, struct spa, spa_dsl_pool, spa.spa_dsl_pool) ||
1541 	    GETMEMB(addr, struct spa, spa_root_vdev, spa.spa_root_vdev) ||
1542 	    GETMEMB(spa.spa_root_vdev, struct vdev, vdev_children, children) ||
1543 	    GETMEMB(spa.spa_root_vdev, struct vdev, vdev_child, childaddr) ||
1544 	    GETMEMB(spa.spa_dsl_pool, struct dsl_pool,
1545 	    dp_root_dir, dp_root_dir) ||
1546 	    GETMEMB(dp_root_dir, struct dsl_dir, dd_phys, dd.dd_phys) ||
1547 	    GETMEMB(dp_root_dir, struct dsl_dir,
1548 	    dd_space_towrite, dd.dd_space_towrite) ||
1549 	    GETMEMB(dd.dd_phys, struct dsl_dir_phys,
1550 	    dd_used_bytes, dsp.dd_used_bytes) ||
1551 	    GETMEMB(dd.dd_phys, struct dsl_dir_phys,
1552 	    dd_compressed_bytes, dsp.dd_compressed_bytes) ||
1553 	    GETMEMB(dd.dd_phys, struct dsl_dir_phys,
1554 	    dd_uncompressed_bytes, dsp.dd_uncompressed_bytes)) {
1555 		return (DCMD_ERR);
1556 	}
1557 
1558 	mdb_printf("dd_space_towrite = %llu%s %llu%s %llu%s %llu%s\n",
1559 	    dd.dd_space_towrite[0] >> shift, suffix,
1560 	    dd.dd_space_towrite[1] >> shift, suffix,
1561 	    dd.dd_space_towrite[2] >> shift, suffix,
1562 	    dd.dd_space_towrite[3] >> shift, suffix);
1563 
1564 	mdb_printf("dd_phys.dd_used_bytes = %llu%s\n",
1565 	    dsp.dd_used_bytes >> shift, suffix);
1566 	mdb_printf("dd_phys.dd_compressed_bytes = %llu%s\n",
1567 	    dsp.dd_compressed_bytes >> shift, suffix);
1568 	mdb_printf("dd_phys.dd_uncompressed_bytes = %llu%s\n",
1569 	    dsp.dd_uncompressed_bytes >> shift, suffix);
1570 
1571 	bzero(&sd, sizeof (sd));
1572 	if (mdb_pwalk("metaslab", space_cb, &sd, addr) != 0) {
1573 		mdb_warn("can't walk metaslabs");
1574 		return (DCMD_ERR);
1575 	}
1576 
1577 	mdb_printf("ms_allocmap = %llu%s %llu%s %llu%s %llu%s\n",
1578 	    sd.ms_allocmap[0] >> shift, suffix,
1579 	    sd.ms_allocmap[1] >> shift, suffix,
1580 	    sd.ms_allocmap[2] >> shift, suffix,
1581 	    sd.ms_allocmap[3] >> shift, suffix);
1582 	mdb_printf("ms_freemap = %llu%s %llu%s %llu%s %llu%s\n",
1583 	    sd.ms_freemap[0] >> shift, suffix,
1584 	    sd.ms_freemap[1] >> shift, suffix,
1585 	    sd.ms_freemap[2] >> shift, suffix,
1586 	    sd.ms_freemap[3] >> shift, suffix);
1587 	mdb_printf("ms_map = %llu%s\n", sd.ms_map >> shift, suffix);
1588 	mdb_printf("last synced avail = %llu%s\n", sd.avail >> shift, suffix);
1589 	mdb_printf("current syncing avail = %llu%s\n",
1590 	    sd.nowavail >> shift, suffix);
1591 
1592 	return (DCMD_OK);
1593 }
1594 
1595 /*
1596  * ::spa_verify
1597  *
1598  * Given a spa_t, verify that that the pool is self-consistent.
1599  * Currently, it only checks to make sure that the vdev tree exists.
1600  */
1601 /* ARGSUSED */
1602 static int
1603 spa_verify(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1604 {
1605 	spa_t spa;
1606 
1607 	if (argc != 0 || !(flags & DCMD_ADDRSPEC))
1608 		return (DCMD_USAGE);
1609 
1610 	if (mdb_vread(&spa, sizeof (spa), addr) == -1) {
1611 		mdb_warn("failed to read spa_t at %p", addr);
1612 		return (DCMD_ERR);
1613 	}
1614 
1615 	if (spa.spa_root_vdev == NULL) {
1616 		mdb_printf("no vdev tree present\n");
1617 		return (DCMD_OK);
1618 	}
1619 
1620 	return (DCMD_OK);
1621 }
1622 
1623 static int
1624 spa_print_aux(spa_aux_vdev_t *sav, uint_t flags, mdb_arg_t *v,
1625     const char *name)
1626 {
1627 	uintptr_t *aux;
1628 	size_t len;
1629 	int ret, i;
1630 
1631 	/*
1632 	 * Iterate over aux vdevs and print those out as well.  This is a
1633 	 * little annoying because we don't have a root vdev to pass to ::vdev.
1634 	 * Instead, we print a single line and then call it for each child
1635 	 * vdev.
1636 	 */
1637 	if (sav->sav_count != 0) {
1638 		v[1].a_type = MDB_TYPE_STRING;
1639 		v[1].a_un.a_str = "-d";
1640 		v[2].a_type = MDB_TYPE_IMMEDIATE;
1641 		v[2].a_un.a_val = 2;
1642 
1643 		len = sav->sav_count * sizeof (uintptr_t);
1644 		aux = mdb_alloc(len, UM_SLEEP);
1645 		if (mdb_vread(aux, len,
1646 		    (uintptr_t)sav->sav_vdevs) == -1) {
1647 			mdb_free(aux, len);
1648 			mdb_warn("failed to read l2cache vdevs at %p",
1649 			    sav->sav_vdevs);
1650 			return (DCMD_ERR);
1651 		}
1652 
1653 		mdb_printf("%-?s %-9s %-12s %s\n", "-", "-", "-", name);
1654 
1655 		for (i = 0; i < sav->sav_count; i++) {
1656 			ret = mdb_call_dcmd("vdev", aux[i], flags, 3, v);
1657 			if (ret != DCMD_OK) {
1658 				mdb_free(aux, len);
1659 				return (ret);
1660 			}
1661 		}
1662 
1663 		mdb_free(aux, len);
1664 	}
1665 
1666 	return (0);
1667 }
1668 
1669 /*
1670  * ::spa_vdevs
1671  *
1672  * 	-e	Include error stats
1673  *
1674  * Print out a summarized list of vdevs for the given spa_t.
1675  * This is accomplished by invoking "::vdev -re" on the root vdev, as well as
1676  * iterating over the cache devices.
1677  */
1678 /* ARGSUSED */
1679 static int
1680 spa_vdevs(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1681 {
1682 	spa_t spa;
1683 	mdb_arg_t v[3];
1684 	int errors = FALSE;
1685 	int ret;
1686 
1687 	if (mdb_getopts(argc, argv,
1688 	    'e', MDB_OPT_SETBITS, TRUE, &errors,
1689 	    NULL) != argc)
1690 		return (DCMD_USAGE);
1691 
1692 	if (!(flags & DCMD_ADDRSPEC))
1693 		return (DCMD_USAGE);
1694 
1695 	if (mdb_vread(&spa, sizeof (spa), addr) == -1) {
1696 		mdb_warn("failed to read spa_t at %p", addr);
1697 		return (DCMD_ERR);
1698 	}
1699 
1700 	/*
1701 	 * Unitialized spa_t structures can have a NULL root vdev.
1702 	 */
1703 	if (spa.spa_root_vdev == NULL) {
1704 		mdb_printf("no associated vdevs\n");
1705 		return (DCMD_OK);
1706 	}
1707 
1708 	v[0].a_type = MDB_TYPE_STRING;
1709 	v[0].a_un.a_str = errors ? "-re" : "-r";
1710 
1711 	ret = mdb_call_dcmd("vdev", (uintptr_t)spa.spa_root_vdev,
1712 	    flags, 1, v);
1713 	if (ret != DCMD_OK)
1714 		return (ret);
1715 
1716 	if (spa_print_aux(&spa.spa_l2cache, flags, v, "cache") != 0 ||
1717 	    spa_print_aux(&spa.spa_spares, flags, v, "spares") != 0)
1718 		return (DCMD_ERR);
1719 
1720 	return (DCMD_OK);
1721 }
1722 
1723 /*
1724  * ::zio
1725  *
1726  * Print a summary of zio_t and all its children.  This is intended to display a
1727  * zio tree, and hence we only pick the most important pieces of information for
1728  * the main summary.  More detailed information can always be found by doing a
1729  * '::print zio' on the underlying zio_t.  The columns we display are:
1730  *
1731  *	ADDRESS		TYPE	STAGE		WAITER
1732  *
1733  * The 'address' column is indented by one space for each depth level as we
1734  * descend down the tree.
1735  */
1736 
1737 #define	ZIO_MAXINDENT	24
1738 #define	ZIO_MAXWIDTH	(sizeof (uintptr_t) * 2 + ZIO_MAXINDENT)
1739 #define	ZIO_WALK_SELF	0
1740 #define	ZIO_WALK_CHILD	1
1741 #define	ZIO_WALK_PARENT	2
1742 
1743 typedef struct zio_print_args {
1744 	int	zpa_current_depth;
1745 	int	zpa_min_depth;
1746 	int	zpa_max_depth;
1747 	int	zpa_type;
1748 	uint_t	zpa_flags;
1749 } zio_print_args_t;
1750 
1751 static int zio_child_cb(uintptr_t addr, const void *unknown, void *arg);
1752 
1753 static int
1754 zio_print_cb(uintptr_t addr, const void *data, void *priv)
1755 {
1756 	const zio_t *zio = data;
1757 	zio_print_args_t *zpa = priv;
1758 	mdb_ctf_id_t type_enum, stage_enum;
1759 	int indent = zpa->zpa_current_depth;
1760 	const char *type, *stage;
1761 	uintptr_t laddr;
1762 
1763 	if (indent > ZIO_MAXINDENT)
1764 		indent = ZIO_MAXINDENT;
1765 
1766 	if (mdb_ctf_lookup_by_name("enum zio_type", &type_enum) == -1 ||
1767 	    mdb_ctf_lookup_by_name("enum zio_stage", &stage_enum) == -1) {
1768 		mdb_warn("failed to lookup zio enums");
1769 		return (WALK_ERR);
1770 	}
1771 
1772 	if ((type = mdb_ctf_enum_name(type_enum, zio->io_type)) != NULL)
1773 		type += sizeof ("ZIO_TYPE_") - 1;
1774 	else
1775 		type = "?";
1776 
1777 	if ((stage = mdb_ctf_enum_name(stage_enum, zio->io_stage)) != NULL)
1778 		stage += sizeof ("ZIO_STAGE_") - 1;
1779 	else
1780 		stage = "?";
1781 
1782 	if (zpa->zpa_current_depth >= zpa->zpa_min_depth) {
1783 		if (zpa->zpa_flags & DCMD_PIPE_OUT) {
1784 			mdb_printf("%?p\n", addr);
1785 		} else {
1786 			mdb_printf("%*s%-*p %-5s %-16s ", indent, "",
1787 			    ZIO_MAXWIDTH - indent, addr, type, stage);
1788 			if (zio->io_waiter)
1789 				mdb_printf("%?p\n", zio->io_waiter);
1790 			else
1791 				mdb_printf("-\n");
1792 		}
1793 	}
1794 
1795 	if (zpa->zpa_current_depth >= zpa->zpa_max_depth)
1796 		return (WALK_NEXT);
1797 
1798 	if (zpa->zpa_type == ZIO_WALK_PARENT)
1799 		laddr = addr + OFFSETOF(zio_t, io_parent_list);
1800 	else
1801 		laddr = addr + OFFSETOF(zio_t, io_child_list);
1802 
1803 	zpa->zpa_current_depth++;
1804 	if (mdb_pwalk("list", zio_child_cb, zpa, laddr) != 0) {
1805 		mdb_warn("failed to walk zio_t children at %p\n", laddr);
1806 		return (WALK_ERR);
1807 	}
1808 	zpa->zpa_current_depth--;
1809 
1810 	return (WALK_NEXT);
1811 }
1812 
1813 /* ARGSUSED */
1814 static int
1815 zio_child_cb(uintptr_t addr, const void *unknown, void *arg)
1816 {
1817 	zio_link_t zl;
1818 	zio_t zio;
1819 	uintptr_t ziop;
1820 	zio_print_args_t *zpa = arg;
1821 
1822 	if (mdb_vread(&zl, sizeof (zl), addr) == -1) {
1823 		mdb_warn("failed to read zio_link_t at %p", addr);
1824 		return (WALK_ERR);
1825 	}
1826 
1827 	if (zpa->zpa_type == ZIO_WALK_PARENT)
1828 		ziop = (uintptr_t)zl.zl_parent;
1829 	else
1830 		ziop = (uintptr_t)zl.zl_child;
1831 
1832 	if (mdb_vread(&zio, sizeof (zio_t), ziop) == -1) {
1833 		mdb_warn("failed to read zio_t at %p", ziop);
1834 		return (WALK_ERR);
1835 	}
1836 
1837 	return (zio_print_cb(ziop, &zio, arg));
1838 }
1839 
1840 /* ARGSUSED */
1841 static int
1842 zio_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1843 {
1844 	zio_t zio;
1845 	zio_print_args_t zpa = { 0 };
1846 
1847 	if (!(flags & DCMD_ADDRSPEC))
1848 		return (DCMD_USAGE);
1849 
1850 	if (mdb_getopts(argc, argv,
1851 	    'r', MDB_OPT_SETBITS, INT_MAX, &zpa.zpa_max_depth,
1852 	    'c', MDB_OPT_SETBITS, ZIO_WALK_CHILD, &zpa.zpa_type,
1853 	    'p', MDB_OPT_SETBITS, ZIO_WALK_PARENT, &zpa.zpa_type,
1854 	    NULL) != argc)
1855 		return (DCMD_USAGE);
1856 
1857 	zpa.zpa_flags = flags;
1858 	if (zpa.zpa_max_depth != 0) {
1859 		if (zpa.zpa_type == ZIO_WALK_SELF)
1860 			zpa.zpa_type = ZIO_WALK_CHILD;
1861 	} else if (zpa.zpa_type != ZIO_WALK_SELF) {
1862 		zpa.zpa_min_depth = 1;
1863 		zpa.zpa_max_depth = 1;
1864 	}
1865 
1866 	if (mdb_vread(&zio, sizeof (zio_t), addr) == -1) {
1867 		mdb_warn("failed to read zio_t at %p", addr);
1868 		return (DCMD_ERR);
1869 	}
1870 
1871 	if (!(flags & DCMD_PIPE_OUT) && DCMD_HDRSPEC(flags))
1872 		mdb_printf("%<u>%-*s %-5s %-16s %-?s%</u>\n", ZIO_MAXWIDTH,
1873 		    "ADDRESS", "TYPE", "STAGE", "WAITER");
1874 
1875 	if (zio_print_cb(addr, &zio, &zpa) != WALK_NEXT)
1876 		return (DCMD_ERR);
1877 
1878 	return (DCMD_OK);
1879 }
1880 
1881 /*
1882  * [addr]::zio_state
1883  *
1884  * Print a summary of all zio_t structures on the system, or for a particular
1885  * pool.  This is equivalent to '::walk zio_root | ::zio'.
1886  */
1887 /*ARGSUSED*/
1888 static int
1889 zio_state(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1890 {
1891 	/*
1892 	 * MDB will remember the last address of the pipeline, so if we don't
1893 	 * zero this we'll end up trying to walk zio structures for a
1894 	 * non-existent spa_t.
1895 	 */
1896 	if (!(flags & DCMD_ADDRSPEC))
1897 		addr = 0;
1898 
1899 	return (mdb_pwalk_dcmd("zio_root", "zio", argc, argv, addr));
1900 }
1901 
1902 typedef struct txg_list_walk_data {
1903 	uintptr_t lw_head[TXG_SIZE];
1904 	int	lw_txgoff;
1905 	int	lw_maxoff;
1906 	size_t	lw_offset;
1907 	void	*lw_obj;
1908 } txg_list_walk_data_t;
1909 
1910 static int
1911 txg_list_walk_init_common(mdb_walk_state_t *wsp, int txg, int maxoff)
1912 {
1913 	txg_list_walk_data_t *lwd;
1914 	txg_list_t list;
1915 	int i;
1916 
1917 	lwd = mdb_alloc(sizeof (txg_list_walk_data_t), UM_SLEEP | UM_GC);
1918 	if (mdb_vread(&list, sizeof (txg_list_t), wsp->walk_addr) == -1) {
1919 		mdb_warn("failed to read txg_list_t at %#lx", wsp->walk_addr);
1920 		return (WALK_ERR);
1921 	}
1922 
1923 	for (i = 0; i < TXG_SIZE; i++)
1924 		lwd->lw_head[i] = (uintptr_t)list.tl_head[i];
1925 	lwd->lw_offset = list.tl_offset;
1926 	lwd->lw_obj = mdb_alloc(lwd->lw_offset + sizeof (txg_node_t),
1927 	    UM_SLEEP | UM_GC);
1928 	lwd->lw_txgoff = txg;
1929 	lwd->lw_maxoff = maxoff;
1930 
1931 	wsp->walk_addr = lwd->lw_head[lwd->lw_txgoff];
1932 	wsp->walk_data = lwd;
1933 
1934 	return (WALK_NEXT);
1935 }
1936 
1937 static int
1938 txg_list_walk_init(mdb_walk_state_t *wsp)
1939 {
1940 	return (txg_list_walk_init_common(wsp, 0, TXG_SIZE-1));
1941 }
1942 
1943 static int
1944 txg_list0_walk_init(mdb_walk_state_t *wsp)
1945 {
1946 	return (txg_list_walk_init_common(wsp, 0, 0));
1947 }
1948 
1949 static int
1950 txg_list1_walk_init(mdb_walk_state_t *wsp)
1951 {
1952 	return (txg_list_walk_init_common(wsp, 1, 1));
1953 }
1954 
1955 static int
1956 txg_list2_walk_init(mdb_walk_state_t *wsp)
1957 {
1958 	return (txg_list_walk_init_common(wsp, 2, 2));
1959 }
1960 
1961 static int
1962 txg_list3_walk_init(mdb_walk_state_t *wsp)
1963 {
1964 	return (txg_list_walk_init_common(wsp, 3, 3));
1965 }
1966 
1967 static int
1968 txg_list_walk_step(mdb_walk_state_t *wsp)
1969 {
1970 	txg_list_walk_data_t *lwd = wsp->walk_data;
1971 	uintptr_t addr;
1972 	txg_node_t *node;
1973 	int status;
1974 
1975 	while (wsp->walk_addr == NULL && lwd->lw_txgoff < lwd->lw_maxoff) {
1976 		lwd->lw_txgoff++;
1977 		wsp->walk_addr = lwd->lw_head[lwd->lw_txgoff];
1978 	}
1979 
1980 	if (wsp->walk_addr == NULL)
1981 		return (WALK_DONE);
1982 
1983 	addr = wsp->walk_addr - lwd->lw_offset;
1984 
1985 	if (mdb_vread(lwd->lw_obj,
1986 	    lwd->lw_offset + sizeof (txg_node_t), addr) == -1) {
1987 		mdb_warn("failed to read list element at %#lx", addr);
1988 		return (WALK_ERR);
1989 	}
1990 
1991 	status = wsp->walk_callback(addr, lwd->lw_obj, wsp->walk_cbdata);
1992 	node = (txg_node_t *)((uintptr_t)lwd->lw_obj + lwd->lw_offset);
1993 	wsp->walk_addr = (uintptr_t)node->tn_next[lwd->lw_txgoff];
1994 
1995 	return (status);
1996 }
1997 
1998 /*
1999  * ::walk spa
2000  *
2001  * Walk all named spa_t structures in the namespace.  This is nothing more than
2002  * a layered avl walk.
2003  */
2004 static int
2005 spa_walk_init(mdb_walk_state_t *wsp)
2006 {
2007 	GElf_Sym sym;
2008 
2009 	if (wsp->walk_addr != NULL) {
2010 		mdb_warn("spa walk only supports global walks\n");
2011 		return (WALK_ERR);
2012 	}
2013 
2014 	if (mdb_lookup_by_obj(ZFS_OBJ_NAME, "spa_namespace_avl", &sym) == -1) {
2015 		mdb_warn("failed to find symbol 'spa_namespace_avl'");
2016 		return (WALK_ERR);
2017 	}
2018 
2019 	wsp->walk_addr = (uintptr_t)sym.st_value;
2020 
2021 	if (mdb_layered_walk("avl", wsp) == -1) {
2022 		mdb_warn("failed to walk 'avl'\n");
2023 		return (WALK_ERR);
2024 	}
2025 
2026 	return (WALK_NEXT);
2027 }
2028 
2029 static int
2030 spa_walk_step(mdb_walk_state_t *wsp)
2031 {
2032 	spa_t	spa;
2033 
2034 	if (mdb_vread(&spa, sizeof (spa), wsp->walk_addr) == -1) {
2035 		mdb_warn("failed to read spa_t at %p", wsp->walk_addr);
2036 		return (WALK_ERR);
2037 	}
2038 
2039 	return (wsp->walk_callback(wsp->walk_addr, &spa, wsp->walk_cbdata));
2040 }
2041 
2042 /*
2043  * [addr]::walk zio
2044  *
2045  * Walk all active zio_t structures on the system.  This is simply a layered
2046  * walk on top of ::walk zio_cache, with the optional ability to limit the
2047  * structures to a particular pool.
2048  */
2049 static int
2050 zio_walk_init(mdb_walk_state_t *wsp)
2051 {
2052 	wsp->walk_data = (void *)wsp->walk_addr;
2053 
2054 	if (mdb_layered_walk("zio_cache", wsp) == -1) {
2055 		mdb_warn("failed to walk 'zio_cache'\n");
2056 		return (WALK_ERR);
2057 	}
2058 
2059 	return (WALK_NEXT);
2060 }
2061 
2062 static int
2063 zio_walk_step(mdb_walk_state_t *wsp)
2064 {
2065 	zio_t zio;
2066 
2067 	if (mdb_vread(&zio, sizeof (zio), wsp->walk_addr) == -1) {
2068 		mdb_warn("failed to read zio_t at %p", wsp->walk_addr);
2069 		return (WALK_ERR);
2070 	}
2071 
2072 	if (wsp->walk_data != NULL && wsp->walk_data != zio.io_spa)
2073 		return (WALK_NEXT);
2074 
2075 	return (wsp->walk_callback(wsp->walk_addr, &zio, wsp->walk_cbdata));
2076 }
2077 
2078 /*
2079  * [addr]::walk zio_root
2080  *
2081  * Walk only root zio_t structures, optionally for a particular spa_t.
2082  */
2083 static int
2084 zio_walk_root_step(mdb_walk_state_t *wsp)
2085 {
2086 	zio_t zio;
2087 
2088 	if (mdb_vread(&zio, sizeof (zio), wsp->walk_addr) == -1) {
2089 		mdb_warn("failed to read zio_t at %p", wsp->walk_addr);
2090 		return (WALK_ERR);
2091 	}
2092 
2093 	if (wsp->walk_data != NULL && wsp->walk_data != zio.io_spa)
2094 		return (WALK_NEXT);
2095 
2096 	/* If the parent list is not empty, ignore */
2097 	if (zio.io_parent_list.list_head.list_next !=
2098 	    &((zio_t *)wsp->walk_addr)->io_parent_list.list_head)
2099 		return (WALK_NEXT);
2100 
2101 	return (wsp->walk_callback(wsp->walk_addr, &zio, wsp->walk_cbdata));
2102 }
2103 
2104 #define	NICENUM_BUFLEN 6
2105 
2106 static int
2107 snprintfrac(char *buf, int len,
2108     uint64_t numerator, uint64_t denom, int frac_digits)
2109 {
2110 	int mul = 1;
2111 	int whole, frac, i;
2112 
2113 	for (i = frac_digits; i; i--)
2114 		mul *= 10;
2115 	whole = numerator / denom;
2116 	frac = mul * numerator / denom - mul * whole;
2117 	return (mdb_snprintf(buf, len, "%u.%0*u", whole, frac_digits, frac));
2118 }
2119 
2120 static void
2121 mdb_nicenum(uint64_t num, char *buf)
2122 {
2123 	uint64_t n = num;
2124 	int index = 0;
2125 	char *u;
2126 
2127 	while (n >= 1024) {
2128 		n = (n + (1024 / 2)) / 1024; /* Round up or down */
2129 		index++;
2130 	}
2131 
2132 	u = &" \0K\0M\0G\0T\0P\0E\0"[index*2];
2133 
2134 	if (index == 0) {
2135 		(void) mdb_snprintf(buf, NICENUM_BUFLEN, "%llu",
2136 		    (u_longlong_t)n);
2137 	} else if (n < 10 && (num & (num - 1)) != 0) {
2138 		(void) snprintfrac(buf, NICENUM_BUFLEN,
2139 		    num, 1ULL << 10 * index, 2);
2140 		strcat(buf, u);
2141 	} else if (n < 100 && (num & (num - 1)) != 0) {
2142 		(void) snprintfrac(buf, NICENUM_BUFLEN,
2143 		    num, 1ULL << 10 * index, 1);
2144 		strcat(buf, u);
2145 	} else {
2146 		(void) mdb_snprintf(buf, NICENUM_BUFLEN, "%llu%s",
2147 		    (u_longlong_t)n, u);
2148 	}
2149 }
2150 
2151 /*
2152  * ::zfs_blkstats
2153  *
2154  * 	-v	print verbose per-level information
2155  *
2156  */
2157 static int
2158 zfs_blkstats(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2159 {
2160 	boolean_t verbose = B_FALSE;
2161 	zfs_all_blkstats_t stats;
2162 	dmu_object_type_t t;
2163 	zfs_blkstat_t *tzb;
2164 	uint64_t ditto;
2165 	dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES + 10];
2166 	/* +10 in case it grew */
2167 
2168 	if (mdb_readvar(&dmu_ot, "dmu_ot") == -1) {
2169 		mdb_warn("failed to read 'dmu_ot'");
2170 		return (DCMD_ERR);
2171 	}
2172 
2173 	if (mdb_getopts(argc, argv,
2174 	    'v', MDB_OPT_SETBITS, TRUE, &verbose,
2175 	    NULL) != argc)
2176 		return (DCMD_USAGE);
2177 
2178 	if (!(flags & DCMD_ADDRSPEC))
2179 		return (DCMD_USAGE);
2180 
2181 	if (GETMEMB(addr, struct spa, spa_dsl_pool, addr) ||
2182 	    GETMEMB(addr, struct dsl_pool, dp_blkstats, addr) ||
2183 	    mdb_vread(&stats, sizeof (zfs_all_blkstats_t), addr) == -1) {
2184 		mdb_warn("failed to read data at %p;", addr);
2185 		mdb_printf("maybe no stats? run \"zpool scrub\" first.");
2186 		return (DCMD_ERR);
2187 	}
2188 
2189 	tzb = &stats.zab_type[DN_MAX_LEVELS][DMU_OT_TOTAL];
2190 	if (tzb->zb_gangs != 0) {
2191 		mdb_printf("Ganged blocks: %llu\n",
2192 		    (longlong_t)tzb->zb_gangs);
2193 	}
2194 
2195 	ditto = tzb->zb_ditto_2_of_2_samevdev + tzb->zb_ditto_2_of_3_samevdev +
2196 	    tzb->zb_ditto_3_of_3_samevdev;
2197 	if (ditto != 0) {
2198 		mdb_printf("Dittoed blocks on same vdev: %llu\n",
2199 		    (longlong_t)ditto);
2200 	}
2201 
2202 	mdb_printf("\nBlocks\tLSIZE\tPSIZE\tASIZE"
2203 	    "\t  avg\t comp\t%%Total\tType\n");
2204 
2205 	for (t = 0; t <= DMU_OT_TOTAL; t++) {
2206 		char csize[NICENUM_BUFLEN], lsize[NICENUM_BUFLEN];
2207 		char psize[NICENUM_BUFLEN], asize[NICENUM_BUFLEN];
2208 		char avg[NICENUM_BUFLEN];
2209 		char comp[NICENUM_BUFLEN], pct[NICENUM_BUFLEN];
2210 		char typename[64];
2211 		int l;
2212 
2213 
2214 		if (t == DMU_OT_DEFERRED)
2215 			strcpy(typename, "deferred free");
2216 		else if (t == DMU_OT_OTHER)
2217 			strcpy(typename, "other");
2218 		else if (t == DMU_OT_TOTAL)
2219 			strcpy(typename, "Total");
2220 		else if (mdb_readstr(typename, sizeof (typename),
2221 		    (uintptr_t)dmu_ot[t].ot_name) == -1) {
2222 			mdb_warn("failed to read type name");
2223 			return (DCMD_ERR);
2224 		}
2225 
2226 		if (stats.zab_type[DN_MAX_LEVELS][t].zb_asize == 0)
2227 			continue;
2228 
2229 		for (l = -1; l < DN_MAX_LEVELS; l++) {
2230 			int level = (l == -1 ? DN_MAX_LEVELS : l);
2231 			zfs_blkstat_t *zb = &stats.zab_type[level][t];
2232 
2233 			if (zb->zb_asize == 0)
2234 				continue;
2235 
2236 			/*
2237 			 * Don't print each level unless requested.
2238 			 */
2239 			if (!verbose && level != DN_MAX_LEVELS)
2240 				continue;
2241 
2242 			/*
2243 			 * If all the space is level 0, don't print the
2244 			 * level 0 separately.
2245 			 */
2246 			if (level == 0 && zb->zb_asize ==
2247 			    stats.zab_type[DN_MAX_LEVELS][t].zb_asize)
2248 				continue;
2249 
2250 			mdb_nicenum(zb->zb_count, csize);
2251 			mdb_nicenum(zb->zb_lsize, lsize);
2252 			mdb_nicenum(zb->zb_psize, psize);
2253 			mdb_nicenum(zb->zb_asize, asize);
2254 			mdb_nicenum(zb->zb_asize / zb->zb_count, avg);
2255 			(void) snprintfrac(comp, NICENUM_BUFLEN,
2256 			    zb->zb_lsize, zb->zb_psize, 2);
2257 			(void) snprintfrac(pct, NICENUM_BUFLEN,
2258 			    100 * zb->zb_asize, tzb->zb_asize, 2);
2259 
2260 			mdb_printf("%6s\t%5s\t%5s\t%5s\t%5s"
2261 			    "\t%5s\t%6s\t",
2262 			    csize, lsize, psize, asize, avg, comp, pct);
2263 
2264 			if (level == DN_MAX_LEVELS)
2265 				mdb_printf("%s\n", typename);
2266 			else
2267 				mdb_printf("  L%d %s\n",
2268 				    level, typename);
2269 		}
2270 	}
2271 
2272 	return (DCMD_OK);
2273 }
2274 
2275 /* ARGSUSED */
2276 static int
2277 reference_cb(uintptr_t addr, const void *ignored, void *arg)
2278 {
2279 	static int gotid;
2280 	static mdb_ctf_id_t ref_id;
2281 	uintptr_t ref_holder;
2282 	uintptr_t ref_removed;
2283 	uint64_t ref_number;
2284 	boolean_t holder_is_str = B_FALSE;
2285 	char holder_str[128];
2286 	boolean_t removed = (boolean_t)arg;
2287 
2288 	if (!gotid) {
2289 		if (mdb_ctf_lookup_by_name("struct reference", &ref_id) == -1) {
2290 			mdb_warn("couldn't find struct reference");
2291 			return (WALK_ERR);
2292 		}
2293 		gotid = TRUE;
2294 	}
2295 
2296 	if (GETMEMBID(addr, &ref_id, ref_holder, ref_holder) ||
2297 	    GETMEMBID(addr, &ref_id, ref_removed, ref_removed) ||
2298 	    GETMEMBID(addr, &ref_id, ref_number, ref_number))
2299 		return (WALK_ERR);
2300 
2301 	if (mdb_readstr(holder_str, sizeof (holder_str), ref_holder) != -1)
2302 		holder_is_str = strisprint(holder_str);
2303 
2304 	if (removed)
2305 		mdb_printf("removed ");
2306 	mdb_printf("reference ");
2307 	if (ref_number != 1)
2308 		mdb_printf("with count=%llu ", ref_number);
2309 	mdb_printf("with tag %p", (void*)ref_holder);
2310 	if (holder_is_str)
2311 		mdb_printf(" \"%s\"", holder_str);
2312 	mdb_printf(", held at:\n");
2313 
2314 	(void) mdb_call_dcmd("whatis", addr, DCMD_ADDRSPEC, 0, NULL);
2315 
2316 	if (removed) {
2317 		mdb_printf("removed at:\n");
2318 		(void) mdb_call_dcmd("whatis", ref_removed,
2319 		    DCMD_ADDRSPEC, 0, NULL);
2320 	}
2321 
2322 	mdb_printf("\n");
2323 
2324 	return (WALK_NEXT);
2325 }
2326 
2327 /* ARGSUSED */
2328 static int
2329 refcount(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2330 {
2331 	uint64_t rc_count, rc_removed_count;
2332 	uintptr_t rc_list, rc_removed;
2333 	static int gotid;
2334 	static mdb_ctf_id_t rc_id;
2335 	ulong_t off;
2336 
2337 	if (!(flags & DCMD_ADDRSPEC))
2338 		return (DCMD_USAGE);
2339 
2340 	if (!gotid) {
2341 		/*
2342 		 * The refcount structure is different when compiled debug
2343 		 * vs nondebug.  Therefore, we want to make sure we get the
2344 		 * refcount definition from the ZFS module, in case it has
2345 		 * been compiled debug but genunix is nondebug.
2346 		 */
2347 		if (mdb_ctf_lookup_by_name("struct " ZFS_OBJ_NAME "`refcount",
2348 		    &rc_id) == -1) {
2349 			mdb_warn("couldn't find struct refcount");
2350 			return (DCMD_ERR);
2351 		}
2352 		gotid = TRUE;
2353 	}
2354 
2355 	if (GETMEMBID(addr, &rc_id, rc_count, rc_count) ||
2356 	    GETMEMBID(addr, &rc_id, rc_removed_count, rc_removed_count))
2357 		return (DCMD_ERR);
2358 
2359 	mdb_printf("refcount_t at %p has %llu current holds, "
2360 	    "%llu recently released holds\n",
2361 	    addr, (longlong_t)rc_count, (longlong_t)rc_removed_count);
2362 
2363 	if (rc_count > 0)
2364 		mdb_printf("current holds:\n");
2365 	if (mdb_ctf_offsetof(rc_id, "rc_list", &off) == -1)
2366 		return (DCMD_ERR);
2367 	rc_list = addr + off/NBBY;
2368 	mdb_pwalk("list", reference_cb, (void*)B_FALSE, rc_list);
2369 
2370 	if (rc_removed_count > 0)
2371 		mdb_printf("released holds:\n");
2372 	if (mdb_ctf_offsetof(rc_id, "rc_removed", &off) == -1)
2373 		return (DCMD_ERR);
2374 	rc_removed = addr + off/NBBY;
2375 	mdb_pwalk("list", reference_cb, (void*)B_TRUE, rc_removed);
2376 
2377 	return (DCMD_OK);
2378 }
2379 
2380 /* ARGSUSED */
2381 static int
2382 sa_attr_table(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2383 {
2384 	sa_attr_table_t *table;
2385 	sa_os_t sa_os;
2386 	char *name;
2387 	int i;
2388 
2389 	if (mdb_vread(&sa_os, sizeof (sa_os_t), addr) == -1) {
2390 		mdb_warn("failed to read sa_os at %p", addr);
2391 		return (DCMD_ERR);
2392 	}
2393 
2394 	table = mdb_alloc(sizeof (sa_attr_table_t) * sa_os.sa_num_attrs,
2395 	    UM_SLEEP | UM_GC);
2396 	name = mdb_alloc(MAXPATHLEN, UM_SLEEP | UM_GC);
2397 
2398 	if (mdb_vread(table, sizeof (sa_attr_table_t) * sa_os.sa_num_attrs,
2399 	    (uintptr_t)sa_os.sa_attr_table) == -1) {
2400 		mdb_warn("failed to read sa_os at %p", addr);
2401 		return (DCMD_ERR);
2402 	}
2403 
2404 	mdb_printf("%<u>%-10s %-10s %-10s %-10s %s%</u>\n",
2405 	    "ATTR ID", "REGISTERED", "LENGTH", "BSWAP", "NAME");
2406 	for (i = 0; i != sa_os.sa_num_attrs; i++) {
2407 		mdb_readstr(name, MAXPATHLEN, (uintptr_t)table[i].sa_name);
2408 		mdb_printf("%5x   %8x %8x %8x          %-s\n",
2409 		    (int)table[i].sa_attr, (int)table[i].sa_registered,
2410 		    (int)table[i].sa_length, table[i].sa_byteswap, name);
2411 	}
2412 
2413 	return (DCMD_OK);
2414 }
2415 
2416 static int
2417 sa_get_off_table(uintptr_t addr, uint32_t **off_tab, int attr_count)
2418 {
2419 	uintptr_t idx_table;
2420 
2421 	if (GETMEMB(addr, struct sa_idx_tab, sa_idx_tab, idx_table)) {
2422 		mdb_printf("can't find offset table in sa_idx_tab\n");
2423 		return (-1);
2424 	}
2425 
2426 	*off_tab = mdb_alloc(attr_count * sizeof (uint32_t),
2427 	    UM_SLEEP | UM_GC);
2428 
2429 	if (mdb_vread(*off_tab,
2430 	    attr_count * sizeof (uint32_t), idx_table) == -1) {
2431 		mdb_warn("failed to attribute offset table %p", idx_table);
2432 		return (-1);
2433 	}
2434 
2435 	return (DCMD_OK);
2436 }
2437 
2438 /*ARGSUSED*/
2439 static int
2440 sa_attr_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2441 {
2442 	uint32_t *offset_tab;
2443 	int attr_count;
2444 	uint64_t attr_id;
2445 	uintptr_t attr_addr;
2446 	uintptr_t bonus_tab, spill_tab;
2447 	uintptr_t db_bonus, db_spill;
2448 	uintptr_t os, os_sa;
2449 	uintptr_t db_data;
2450 
2451 	if (argc != 1)
2452 		return (DCMD_USAGE);
2453 
2454 	if (argv[0].a_type == MDB_TYPE_STRING)
2455 		attr_id = mdb_strtoull(argv[0].a_un.a_str);
2456 	else
2457 		return (DCMD_USAGE);
2458 
2459 	if (GETMEMB(addr, struct sa_handle, sa_bonus_tab, bonus_tab) ||
2460 	    GETMEMB(addr, struct sa_handle, sa_spill_tab, spill_tab) ||
2461 	    GETMEMB(addr, struct sa_handle, sa_os, os) ||
2462 	    GETMEMB(addr, struct sa_handle, sa_bonus, db_bonus) ||
2463 	    GETMEMB(addr, struct sa_handle, sa_spill, db_spill)) {
2464 		mdb_printf("Can't find necessary information in sa_handle "
2465 		    "in sa_handle\n");
2466 		return (DCMD_ERR);
2467 	}
2468 
2469 	if (GETMEMB(os, struct objset, os_sa, os_sa)) {
2470 		mdb_printf("Can't find os_sa in objset\n");
2471 		return (DCMD_ERR);
2472 	}
2473 
2474 	if (GETMEMB(os_sa, struct sa_os, sa_num_attrs, attr_count)) {
2475 		mdb_printf("Can't find sa_num_attrs\n");
2476 		return (DCMD_ERR);
2477 	}
2478 
2479 	if (attr_id > attr_count) {
2480 		mdb_printf("attribute id number is out of range\n");
2481 		return (DCMD_ERR);
2482 	}
2483 
2484 	if (bonus_tab) {
2485 		if (sa_get_off_table(bonus_tab, &offset_tab,
2486 		    attr_count) == -1) {
2487 			return (DCMD_ERR);
2488 		}
2489 
2490 		if (GETMEMB(db_bonus, struct dmu_buf, db_data, db_data)) {
2491 			mdb_printf("can't find db_data in bonus dbuf\n");
2492 			return (DCMD_ERR);
2493 		}
2494 	}
2495 
2496 	if (bonus_tab && !TOC_ATTR_PRESENT(offset_tab[attr_id]) &&
2497 	    spill_tab == NULL) {
2498 		mdb_printf("Attribute does not exist\n");
2499 		return (DCMD_ERR);
2500 	} else if (!TOC_ATTR_PRESENT(offset_tab[attr_id]) && spill_tab) {
2501 		if (sa_get_off_table(spill_tab, &offset_tab,
2502 		    attr_count) == -1) {
2503 			return (DCMD_ERR);
2504 		}
2505 		if (GETMEMB(db_spill, struct dmu_buf, db_data, db_data)) {
2506 			mdb_printf("can't find db_data in spill dbuf\n");
2507 			return (DCMD_ERR);
2508 		}
2509 		if (!TOC_ATTR_PRESENT(offset_tab[attr_id])) {
2510 			mdb_printf("Attribute does not exist\n");
2511 			return (DCMD_ERR);
2512 		}
2513 	}
2514 	attr_addr = db_data + TOC_OFF(offset_tab[attr_id]);
2515 	mdb_printf("%p\n", attr_addr);
2516 	return (DCMD_OK);
2517 }
2518 
2519 /* ARGSUSED */
2520 static int
2521 zfs_ace_print_common(uintptr_t addr, uint_t flags,
2522     uint64_t id, uint32_t access_mask, uint16_t ace_flags,
2523     uint16_t ace_type, int verbose)
2524 {
2525 	if (DCMD_HDRSPEC(flags) && !verbose)
2526 		mdb_printf("%<u>%-?s %-8s %-8s %-8s %s%</u>\n",
2527 		    "ADDR", "FLAGS", "MASK", "TYPE", "ID");
2528 
2529 	if (!verbose) {
2530 		mdb_printf("%0?p %-8x %-8x %-8x %-llx\n", addr,
2531 		    ace_flags, access_mask, ace_type, id);
2532 		return (DCMD_OK);
2533 	}
2534 
2535 	switch (ace_flags & ACE_TYPE_FLAGS) {
2536 	case ACE_OWNER:
2537 		mdb_printf("owner@:");
2538 		break;
2539 	case (ACE_IDENTIFIER_GROUP | ACE_GROUP):
2540 		mdb_printf("group@:");
2541 		break;
2542 	case ACE_EVERYONE:
2543 		mdb_printf("everyone@:");
2544 		break;
2545 	case ACE_IDENTIFIER_GROUP:
2546 		mdb_printf("group:%llx:", (u_longlong_t)id);
2547 		break;
2548 	case 0: /* User entry */
2549 		mdb_printf("user:%llx:", (u_longlong_t)id);
2550 		break;
2551 	}
2552 
2553 	/* print out permission mask */
2554 	if (access_mask & ACE_READ_DATA)
2555 		mdb_printf("r");
2556 	else
2557 		mdb_printf("-");
2558 	if (access_mask & ACE_WRITE_DATA)
2559 		mdb_printf("w");
2560 	else
2561 		mdb_printf("-");
2562 	if (access_mask & ACE_EXECUTE)
2563 		mdb_printf("x");
2564 	else
2565 		mdb_printf("-");
2566 	if (access_mask & ACE_APPEND_DATA)
2567 		mdb_printf("p");
2568 	else
2569 		mdb_printf("-");
2570 	if (access_mask & ACE_DELETE)
2571 		mdb_printf("d");
2572 	else
2573 		mdb_printf("-");
2574 	if (access_mask & ACE_DELETE_CHILD)
2575 		mdb_printf("D");
2576 	else
2577 		mdb_printf("-");
2578 	if (access_mask & ACE_READ_ATTRIBUTES)
2579 		mdb_printf("a");
2580 	else
2581 		mdb_printf("-");
2582 	if (access_mask & ACE_WRITE_ATTRIBUTES)
2583 		mdb_printf("A");
2584 	else
2585 		mdb_printf("-");
2586 	if (access_mask & ACE_READ_NAMED_ATTRS)
2587 		mdb_printf("R");
2588 	else
2589 		mdb_printf("-");
2590 	if (access_mask & ACE_WRITE_NAMED_ATTRS)
2591 		mdb_printf("W");
2592 	else
2593 		mdb_printf("-");
2594 	if (access_mask & ACE_READ_ACL)
2595 		mdb_printf("c");
2596 	else
2597 		mdb_printf("-");
2598 	if (access_mask & ACE_WRITE_ACL)
2599 		mdb_printf("C");
2600 	else
2601 		mdb_printf("-");
2602 	if (access_mask & ACE_WRITE_OWNER)
2603 		mdb_printf("o");
2604 	else
2605 		mdb_printf("-");
2606 	if (access_mask & ACE_SYNCHRONIZE)
2607 		mdb_printf("s");
2608 	else
2609 		mdb_printf("-");
2610 
2611 	mdb_printf(":");
2612 
2613 	/* Print out inheritance flags */
2614 	if (ace_flags & ACE_FILE_INHERIT_ACE)
2615 		mdb_printf("f");
2616 	else
2617 		mdb_printf("-");
2618 	if (ace_flags & ACE_DIRECTORY_INHERIT_ACE)
2619 		mdb_printf("d");
2620 	else
2621 		mdb_printf("-");
2622 	if (ace_flags & ACE_INHERIT_ONLY_ACE)
2623 		mdb_printf("i");
2624 	else
2625 		mdb_printf("-");
2626 	if (ace_flags & ACE_NO_PROPAGATE_INHERIT_ACE)
2627 		mdb_printf("n");
2628 	else
2629 		mdb_printf("-");
2630 	if (ace_flags & ACE_SUCCESSFUL_ACCESS_ACE_FLAG)
2631 		mdb_printf("S");
2632 	else
2633 		mdb_printf("-");
2634 	if (ace_flags & ACE_FAILED_ACCESS_ACE_FLAG)
2635 		mdb_printf("F");
2636 	else
2637 		mdb_printf("-");
2638 	if (ace_flags & ACE_INHERITED_ACE)
2639 		mdb_printf("I");
2640 	else
2641 		mdb_printf("-");
2642 
2643 	switch (ace_type) {
2644 	case ACE_ACCESS_ALLOWED_ACE_TYPE:
2645 		mdb_printf(":allow\n");
2646 		break;
2647 	case ACE_ACCESS_DENIED_ACE_TYPE:
2648 		mdb_printf(":deny\n");
2649 		break;
2650 	case ACE_SYSTEM_AUDIT_ACE_TYPE:
2651 		mdb_printf(":audit\n");
2652 		break;
2653 	case ACE_SYSTEM_ALARM_ACE_TYPE:
2654 		mdb_printf(":alarm\n");
2655 		break;
2656 	default:
2657 		mdb_printf(":?\n");
2658 	}
2659 	return (DCMD_OK);
2660 }
2661 
2662 /* ARGSUSED */
2663 static int
2664 zfs_ace_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2665 {
2666 	zfs_ace_t zace;
2667 	int verbose = FALSE;
2668 	uint64_t id;
2669 
2670 	if (!(flags & DCMD_ADDRSPEC))
2671 		return (DCMD_USAGE);
2672 
2673 	if (mdb_getopts(argc, argv,
2674 	    'v', MDB_OPT_SETBITS, TRUE, &verbose, TRUE, NULL) != argc)
2675 		return (DCMD_USAGE);
2676 
2677 	if (mdb_vread(&zace, sizeof (zfs_ace_t), addr) == -1) {
2678 		mdb_warn("failed to read zfs_ace_t");
2679 		return (DCMD_ERR);
2680 	}
2681 
2682 	if ((zace.z_hdr.z_flags & ACE_TYPE_FLAGS) == 0 ||
2683 	    (zace.z_hdr.z_flags & ACE_TYPE_FLAGS) == ACE_IDENTIFIER_GROUP)
2684 		id = zace.z_fuid;
2685 	else
2686 		id = -1;
2687 
2688 	return (zfs_ace_print_common(addr, flags, id, zace.z_hdr.z_access_mask,
2689 	    zace.z_hdr.z_flags, zace.z_hdr.z_type, verbose));
2690 }
2691 
2692 /* ARGSUSED */
2693 static int
2694 zfs_ace0_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2695 {
2696 	ace_t ace;
2697 	uint64_t id;
2698 	int verbose = FALSE;
2699 
2700 	if (!(flags & DCMD_ADDRSPEC))
2701 		return (DCMD_USAGE);
2702 
2703 	if (mdb_getopts(argc, argv,
2704 	    'v', MDB_OPT_SETBITS, TRUE, &verbose, TRUE, NULL) != argc)
2705 		return (DCMD_USAGE);
2706 
2707 	if (mdb_vread(&ace, sizeof (ace_t), addr) == -1) {
2708 		mdb_warn("failed to read ace_t");
2709 		return (DCMD_ERR);
2710 	}
2711 
2712 	if ((ace.a_flags & ACE_TYPE_FLAGS) == 0 ||
2713 	    (ace.a_flags & ACE_TYPE_FLAGS) == ACE_IDENTIFIER_GROUP)
2714 		id = ace.a_who;
2715 	else
2716 		id = -1;
2717 
2718 	return (zfs_ace_print_common(addr, flags, id, ace.a_access_mask,
2719 	    ace.a_flags, ace.a_type, verbose));
2720 }
2721 
2722 typedef struct acl_dump_args {
2723 	int a_argc;
2724 	const mdb_arg_t *a_argv;
2725 	uint16_t a_version;
2726 	int a_flags;
2727 } acl_dump_args_t;
2728 
2729 /* ARGSUSED */
2730 static int
2731 acl_aces_cb(uintptr_t addr, const void *unknown, void *arg)
2732 {
2733 	acl_dump_args_t *acl_args = (acl_dump_args_t *)arg;
2734 
2735 	if (acl_args->a_version == 1) {
2736 		if (mdb_call_dcmd("zfs_ace", addr,
2737 		    DCMD_ADDRSPEC|acl_args->a_flags, acl_args->a_argc,
2738 		    acl_args->a_argv) != DCMD_OK) {
2739 			return (WALK_ERR);
2740 		}
2741 	} else {
2742 		if (mdb_call_dcmd("zfs_ace0", addr,
2743 		    DCMD_ADDRSPEC|acl_args->a_flags, acl_args->a_argc,
2744 		    acl_args->a_argv) != DCMD_OK) {
2745 			return (WALK_ERR);
2746 		}
2747 	}
2748 	acl_args->a_flags = DCMD_LOOP;
2749 	return (WALK_NEXT);
2750 }
2751 
2752 /* ARGSUSED */
2753 static int
2754 acl_cb(uintptr_t addr, const void *unknown, void *arg)
2755 {
2756 	acl_dump_args_t *acl_args = (acl_dump_args_t *)arg;
2757 
2758 	if (acl_args->a_version == 1) {
2759 		if (mdb_pwalk("zfs_acl_node_aces", acl_aces_cb,
2760 		    arg, addr) != 0) {
2761 			mdb_warn("can't walk ACEs");
2762 			return (DCMD_ERR);
2763 		}
2764 	} else {
2765 		if (mdb_pwalk("zfs_acl_node_aces0", acl_aces_cb,
2766 		    arg, addr) != 0) {
2767 			mdb_warn("can't walk ACEs");
2768 			return (DCMD_ERR);
2769 		}
2770 	}
2771 	return (WALK_NEXT);
2772 }
2773 
2774 /* ARGSUSED */
2775 static int
2776 zfs_acl_dump(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2777 {
2778 	zfs_acl_t zacl;
2779 	int verbose = FALSE;
2780 	acl_dump_args_t acl_args;
2781 
2782 	if (!(flags & DCMD_ADDRSPEC))
2783 		return (DCMD_USAGE);
2784 
2785 	if (mdb_getopts(argc, argv,
2786 	    'v', MDB_OPT_SETBITS, TRUE, &verbose, TRUE, NULL) != argc)
2787 		return (DCMD_USAGE);
2788 
2789 	if (mdb_vread(&zacl, sizeof (zfs_acl_t), addr) == -1) {
2790 		mdb_warn("failed to read zfs_acl_t");
2791 		return (DCMD_ERR);
2792 	}
2793 
2794 	acl_args.a_argc = argc;
2795 	acl_args.a_argv = argv;
2796 	acl_args.a_version = zacl.z_version;
2797 	acl_args.a_flags = DCMD_LOOPFIRST;
2798 
2799 	if (mdb_pwalk("zfs_acl_node", acl_cb, &acl_args, addr) != 0) {
2800 		mdb_warn("can't walk ACL");
2801 		return (DCMD_ERR);
2802 	}
2803 
2804 	return (DCMD_OK);
2805 }
2806 
2807 /* ARGSUSED */
2808 static int
2809 zfs_acl_node_walk_init(mdb_walk_state_t *wsp)
2810 {
2811 	if (wsp->walk_addr == NULL) {
2812 		mdb_warn("must supply address of zfs_acl_node_t\n");
2813 		return (WALK_ERR);
2814 	}
2815 
2816 	wsp->walk_addr += OFFSETOF(zfs_acl_t, z_acl);
2817 
2818 	if (mdb_layered_walk("list", wsp) == -1) {
2819 		mdb_warn("failed to walk 'list'\n");
2820 		return (WALK_ERR);
2821 	}
2822 
2823 	return (WALK_NEXT);
2824 }
2825 
2826 static int
2827 zfs_acl_node_walk_step(mdb_walk_state_t *wsp)
2828 {
2829 	zfs_acl_node_t	aclnode;
2830 
2831 	if (mdb_vread(&aclnode, sizeof (zfs_acl_node_t),
2832 	    wsp->walk_addr) == -1) {
2833 		mdb_warn("failed to read zfs_acl_node at %p", wsp->walk_addr);
2834 		return (WALK_ERR);
2835 	}
2836 
2837 	return (wsp->walk_callback(wsp->walk_addr, &aclnode, wsp->walk_cbdata));
2838 }
2839 
2840 typedef struct ace_walk_data {
2841 	int		ace_count;
2842 	int		ace_version;
2843 } ace_walk_data_t;
2844 
2845 static int
2846 zfs_aces_walk_init_common(mdb_walk_state_t *wsp, int version,
2847     int ace_count, uintptr_t ace_data)
2848 {
2849 	ace_walk_data_t *ace_walk_data;
2850 
2851 	if (wsp->walk_addr == NULL) {
2852 		mdb_warn("must supply address of zfs_acl_node_t\n");
2853 		return (WALK_ERR);
2854 	}
2855 
2856 	ace_walk_data = mdb_alloc(sizeof (ace_walk_data_t), UM_SLEEP | UM_GC);
2857 
2858 	ace_walk_data->ace_count = ace_count;
2859 	ace_walk_data->ace_version = version;
2860 
2861 	wsp->walk_addr = ace_data;
2862 	wsp->walk_data = ace_walk_data;
2863 
2864 	return (WALK_NEXT);
2865 }
2866 
2867 static int
2868 zfs_acl_node_aces_walk_init_common(mdb_walk_state_t *wsp, int version)
2869 {
2870 	static int gotid;
2871 	static mdb_ctf_id_t acl_id;
2872 	int z_ace_count;
2873 	uintptr_t z_acldata;
2874 
2875 	if (!gotid) {
2876 		if (mdb_ctf_lookup_by_name("struct zfs_acl_node",
2877 		    &acl_id) == -1) {
2878 			mdb_warn("couldn't find struct zfs_acl_node");
2879 			return (DCMD_ERR);
2880 		}
2881 		gotid = TRUE;
2882 	}
2883 
2884 	if (GETMEMBID(wsp->walk_addr, &acl_id, z_ace_count, z_ace_count)) {
2885 		return (DCMD_ERR);
2886 	}
2887 	if (GETMEMBID(wsp->walk_addr, &acl_id, z_acldata, z_acldata)) {
2888 		return (DCMD_ERR);
2889 	}
2890 
2891 	return (zfs_aces_walk_init_common(wsp, version,
2892 	    z_ace_count, z_acldata));
2893 }
2894 
2895 /* ARGSUSED */
2896 static int
2897 zfs_acl_node_aces_walk_init(mdb_walk_state_t *wsp)
2898 {
2899 	return (zfs_acl_node_aces_walk_init_common(wsp, 1));
2900 }
2901 
2902 /* ARGSUSED */
2903 static int
2904 zfs_acl_node_aces0_walk_init(mdb_walk_state_t *wsp)
2905 {
2906 	return (zfs_acl_node_aces_walk_init_common(wsp, 0));
2907 }
2908 
2909 static int
2910 zfs_aces_walk_step(mdb_walk_state_t *wsp)
2911 {
2912 	ace_walk_data_t *ace_data = wsp->walk_data;
2913 	zfs_ace_t zace;
2914 	ace_t *acep;
2915 	int status;
2916 	int entry_type;
2917 	int allow_type;
2918 	uintptr_t ptr;
2919 
2920 	if (ace_data->ace_count == 0)
2921 		return (WALK_DONE);
2922 
2923 	if (mdb_vread(&zace, sizeof (zfs_ace_t), wsp->walk_addr) == -1) {
2924 		mdb_warn("failed to read zfs_ace_t at %#lx",
2925 		    wsp->walk_addr);
2926 		return (WALK_ERR);
2927 	}
2928 
2929 	switch (ace_data->ace_version) {
2930 	case 0:
2931 		acep = (ace_t *)&zace;
2932 		entry_type = acep->a_flags & ACE_TYPE_FLAGS;
2933 		allow_type = acep->a_type;
2934 		break;
2935 	case 1:
2936 		entry_type = zace.z_hdr.z_flags & ACE_TYPE_FLAGS;
2937 		allow_type = zace.z_hdr.z_type;
2938 		break;
2939 	default:
2940 		return (WALK_ERR);
2941 	}
2942 
2943 	ptr = (uintptr_t)wsp->walk_addr;
2944 	switch (entry_type) {
2945 	case ACE_OWNER:
2946 	case ACE_EVERYONE:
2947 	case (ACE_IDENTIFIER_GROUP | ACE_GROUP):
2948 		ptr += ace_data->ace_version == 0 ?
2949 		    sizeof (ace_t) : sizeof (zfs_ace_hdr_t);
2950 		break;
2951 	case ACE_IDENTIFIER_GROUP:
2952 	default:
2953 		switch (allow_type) {
2954 		case ACE_ACCESS_ALLOWED_OBJECT_ACE_TYPE:
2955 		case ACE_ACCESS_DENIED_OBJECT_ACE_TYPE:
2956 		case ACE_SYSTEM_AUDIT_OBJECT_ACE_TYPE:
2957 		case ACE_SYSTEM_ALARM_OBJECT_ACE_TYPE:
2958 			ptr += ace_data->ace_version == 0 ?
2959 			    sizeof (ace_t) : sizeof (zfs_object_ace_t);
2960 			break;
2961 		default:
2962 			ptr += ace_data->ace_version == 0 ?
2963 			    sizeof (ace_t) : sizeof (zfs_ace_t);
2964 			break;
2965 		}
2966 	}
2967 
2968 	ace_data->ace_count--;
2969 	status = wsp->walk_callback(wsp->walk_addr,
2970 	    (void *)(uintptr_t)&zace, wsp->walk_cbdata);
2971 
2972 	wsp->walk_addr = ptr;
2973 	return (status);
2974 }
2975 
2976 /*
2977  * MDB module linkage information:
2978  *
2979  * We declare a list of structures describing our dcmds, and a function
2980  * named _mdb_init to return a pointer to our module information.
2981  */
2982 
2983 static const mdb_dcmd_t dcmds[] = {
2984 	{ "arc", "[-bkmg]", "print ARC variables", arc_print },
2985 	{ "blkptr", ":", "print blkptr_t", blkptr },
2986 	{ "dbuf", ":", "print dmu_buf_impl_t", dbuf },
2987 	{ "dbuf_stats", ":", "dbuf stats", dbuf_stats },
2988 	{ "dbufs",
2989 	    "\t[-O objset_t*] [-n objset_name | \"mos\"] "
2990 	    "[-o object | \"mdn\"] \n"
2991 	    "\t[-l level] [-b blkid | \"bonus\"]",
2992 	    "find dmu_buf_impl_t's that match specified criteria", dbufs },
2993 	{ "abuf_find", "dva_word[0] dva_word[1]",
2994 	    "find arc_buf_hdr_t of a specified DVA",
2995 	    abuf_find },
2996 	{ "spa", "?[-cv]", "spa_t summary", spa_print },
2997 	{ "spa_config", ":", "print spa_t configuration", spa_print_config },
2998 	{ "spa_verify", ":", "verify spa_t consistency", spa_verify },
2999 	{ "spa_space", ":[-b]", "print spa_t on-disk space usage", spa_space },
3000 	{ "spa_vdevs", ":", "given a spa_t, print vdev summary", spa_vdevs },
3001 	{ "vdev", ":[-re]\n"
3002 	    "\t-r display recursively\n"
3003 	    "\t-e print statistics",
3004 	    "vdev_t summary", vdev_print },
3005 	{ "zio", ":[cpr]\n"
3006 	    "\t-c display children\n"
3007 	    "\t-p display parents\n"
3008 	    "\t-r display recursively",
3009 	    "zio_t summary", zio_print },
3010 	{ "zio_state", "?", "print out all zio_t structures on system or "
3011 	    "for a particular pool", zio_state },
3012 	{ "zfs_blkstats", ":[-v]",
3013 	    "given a spa_t, print block type stats from last scrub",
3014 	    zfs_blkstats },
3015 	{ "zfs_params", "", "print zfs tunable parameters", zfs_params },
3016 	{ "refcount", "", "print refcount_t holders", refcount },
3017 	{ "zap_leaf", "", "print zap_leaf_phys_t", zap_leaf },
3018 	{ "zfs_aces", ":[-v]", "print all ACEs from a zfs_acl_t",
3019 	    zfs_acl_dump },
3020 	{ "zfs_ace", ":[-v]", "print zfs_ace", zfs_ace_print },
3021 	{ "zfs_ace0", ":[-v]", "print zfs_ace0", zfs_ace0_print },
3022 	{ "sa_attr_table", ":", "print SA attribute table from sa_os_t",
3023 	    sa_attr_table},
3024 	{ "sa_attr", ": attr_id",
3025 	    "print SA attribute address when given sa_handle_t", sa_attr_print},
3026 	{ "zfs_dbgmsg", ":[-v]",
3027 	    "print zfs debug log", dbgmsg},
3028 	{ NULL }
3029 };
3030 
3031 static const mdb_walker_t walkers[] = {
3032 	{ "zms_freelist", "walk ZFS metaslab freelist",
3033 		freelist_walk_init, freelist_walk_step, NULL },
3034 	{ "txg_list", "given any txg_list_t *, walk all entries in all txgs",
3035 		txg_list_walk_init, txg_list_walk_step, NULL },
3036 	{ "txg_list0", "given any txg_list_t *, walk all entries in txg 0",
3037 		txg_list0_walk_init, txg_list_walk_step, NULL },
3038 	{ "txg_list1", "given any txg_list_t *, walk all entries in txg 1",
3039 		txg_list1_walk_init, txg_list_walk_step, NULL },
3040 	{ "txg_list2", "given any txg_list_t *, walk all entries in txg 2",
3041 		txg_list2_walk_init, txg_list_walk_step, NULL },
3042 	{ "txg_list3", "given any txg_list_t *, walk all entries in txg 3",
3043 		txg_list3_walk_init, txg_list_walk_step, NULL },
3044 	{ "zio", "walk all zio structures, optionally for a particular spa_t",
3045 		zio_walk_init, zio_walk_step, NULL },
3046 	{ "zio_root", "walk all root zio_t structures, optionally for a "
3047 	    "particular spa_t",
3048 		zio_walk_init, zio_walk_root_step, NULL },
3049 	{ "spa", "walk all spa_t entries in the namespace",
3050 		spa_walk_init, spa_walk_step, NULL },
3051 	{ "metaslab", "given a spa_t *, walk all metaslab_t structures",
3052 		metaslab_walk_init, metaslab_walk_step, NULL },
3053 	{ "zfs_acl_node", "given a zfs_acl_t, walk all zfs_acl_nodes",
3054 	    zfs_acl_node_walk_init, zfs_acl_node_walk_step, NULL },
3055 	{ "zfs_acl_node_aces", "given a zfs_acl_node_t, walk all ACEs",
3056 	    zfs_acl_node_aces_walk_init, zfs_aces_walk_step, NULL },
3057 	{ "zfs_acl_node_aces0",
3058 	    "given a zfs_acl_node_t, walk all ACEs as ace_t",
3059 	    zfs_acl_node_aces0_walk_init, zfs_aces_walk_step, NULL },
3060 	{ NULL }
3061 };
3062 
3063 static const mdb_modinfo_t modinfo = {
3064 	MDB_API_VERSION, dcmds, walkers
3065 };
3066 
3067 const mdb_modinfo_t *
3068 _mdb_init(void)
3069 {
3070 	return (&modinfo);
3071 }
3072