xref: /illumos-gate/usr/src/cmd/mdb/common/modules/zfs/zfs.c (revision 59ee40951f56cfa1c0e6c5c6aeea10605267116a)
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) 2011, 2016 by Delphix. All rights reserved.
25  * Copyright (c) 2017, Joyent, Inc.  All rights reserved.
26  */
27 
28 /* Portions Copyright 2010 Robert Milkowski */
29 
30 #include <mdb/mdb_ctf.h>
31 #include <sys/zfs_context.h>
32 #include <sys/mdb_modapi.h>
33 #include <sys/dbuf.h>
34 #include <sys/dmu_objset.h>
35 #include <sys/dsl_dir.h>
36 #include <sys/dsl_pool.h>
37 #include <sys/metaslab_impl.h>
38 #include <sys/space_map.h>
39 #include <sys/list.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 #include <sys/multilist.h>
47 
48 #ifdef _KERNEL
49 #define	ZFS_OBJ_NAME	"zfs"
50 extern int64_t mdb_gethrtime(void);
51 #else
52 #define	ZFS_OBJ_NAME	"libzpool.so.1"
53 #endif
54 
55 #define	ZFS_STRUCT	"struct " ZFS_OBJ_NAME "`"
56 
57 #ifndef _KERNEL
58 int aok;
59 #endif
60 
61 enum spa_flags {
62 	SPA_FLAG_CONFIG			= 1 << 0,
63 	SPA_FLAG_VDEVS			= 1 << 1,
64 	SPA_FLAG_ERRORS			= 1 << 2,
65 	SPA_FLAG_METASLAB_GROUPS	= 1 << 3,
66 	SPA_FLAG_METASLABS		= 1 << 4,
67 	SPA_FLAG_HISTOGRAMS		= 1 << 5
68 };
69 
70 /*
71  * If any of these flags are set, call spa_vdevs in spa_print
72  */
73 #define	SPA_FLAG_ALL_VDEV	\
74 	(SPA_FLAG_VDEVS | SPA_FLAG_ERRORS | SPA_FLAG_METASLAB_GROUPS | \
75 	SPA_FLAG_METASLABS)
76 
77 static int
78 getmember(uintptr_t addr, const char *type, mdb_ctf_id_t *idp,
79     const char *member, int len, void *buf)
80 {
81 	mdb_ctf_id_t id;
82 	ulong_t off;
83 	char name[64];
84 
85 	if (idp == NULL) {
86 		if (mdb_ctf_lookup_by_name(type, &id) == -1) {
87 			mdb_warn("couldn't find type %s", type);
88 			return (DCMD_ERR);
89 		}
90 		idp = &id;
91 	} else {
92 		type = name;
93 		mdb_ctf_type_name(*idp, name, sizeof (name));
94 	}
95 
96 	if (mdb_ctf_offsetof(*idp, member, &off) == -1) {
97 		mdb_warn("couldn't find member %s of type %s\n", member, type);
98 		return (DCMD_ERR);
99 	}
100 	if (off % 8 != 0) {
101 		mdb_warn("member %s of type %s is unsupported bitfield",
102 		    member, type);
103 		return (DCMD_ERR);
104 	}
105 	off /= 8;
106 
107 	if (mdb_vread(buf, len, addr + off) == -1) {
108 		mdb_warn("failed to read %s from %s at %p",
109 		    member, type, addr + off);
110 		return (DCMD_ERR);
111 	}
112 	/* mdb_warn("read %s from %s at %p+%llx\n", member, type, addr, off); */
113 
114 	return (0);
115 }
116 
117 #define	GETMEMB(addr, structname, member, dest) \
118 	getmember(addr, ZFS_STRUCT structname, NULL, #member, \
119 	sizeof (dest), &(dest))
120 
121 #define	GETMEMBID(addr, ctfid, member, dest) \
122 	getmember(addr, NULL, ctfid, #member, sizeof (dest), &(dest))
123 
124 static boolean_t
125 strisprint(const char *cp)
126 {
127 	for (; *cp; cp++) {
128 		if (!isprint(*cp))
129 			return (B_FALSE);
130 	}
131 	return (B_TRUE);
132 }
133 
134 #define	NICENUM_BUFLEN 6
135 
136 static int
137 snprintfrac(char *buf, int len,
138     uint64_t numerator, uint64_t denom, int frac_digits)
139 {
140 	int mul = 1;
141 	int whole, frac, i;
142 
143 	for (i = frac_digits; i; i--)
144 		mul *= 10;
145 	whole = numerator / denom;
146 	frac = mul * numerator / denom - mul * whole;
147 	return (mdb_snprintf(buf, len, "%u.%0*u", whole, frac_digits, frac));
148 }
149 
150 static void
151 mdb_nicenum(uint64_t num, char *buf)
152 {
153 	uint64_t n = num;
154 	int index = 0;
155 	char *u;
156 
157 	while (n >= 1024) {
158 		n = (n + (1024 / 2)) / 1024; /* Round up or down */
159 		index++;
160 	}
161 
162 	u = &" \0K\0M\0G\0T\0P\0E\0"[index*2];
163 
164 	if (index == 0) {
165 		(void) mdb_snprintf(buf, NICENUM_BUFLEN, "%llu",
166 		    (u_longlong_t)n);
167 	} else if (n < 10 && (num & (num - 1)) != 0) {
168 		(void) snprintfrac(buf, NICENUM_BUFLEN,
169 		    num, 1ULL << 10 * index, 2);
170 		strcat(buf, u);
171 	} else if (n < 100 && (num & (num - 1)) != 0) {
172 		(void) snprintfrac(buf, NICENUM_BUFLEN,
173 		    num, 1ULL << 10 * index, 1);
174 		strcat(buf, u);
175 	} else {
176 		(void) mdb_snprintf(buf, NICENUM_BUFLEN, "%llu%s",
177 		    (u_longlong_t)n, u);
178 	}
179 }
180 
181 static int verbose;
182 
183 static int
184 freelist_walk_init(mdb_walk_state_t *wsp)
185 {
186 	if (wsp->walk_addr == NULL) {
187 		mdb_warn("must supply starting address\n");
188 		return (WALK_ERR);
189 	}
190 
191 	wsp->walk_data = 0;  /* Index into the freelist */
192 	return (WALK_NEXT);
193 }
194 
195 static int
196 freelist_walk_step(mdb_walk_state_t *wsp)
197 {
198 	uint64_t entry;
199 	uintptr_t number = (uintptr_t)wsp->walk_data;
200 	char *ddata[] = { "ALLOC", "FREE", "CONDENSE", "INVALID",
201 			    "INVALID", "INVALID", "INVALID", "INVALID" };
202 	int mapshift = SPA_MINBLOCKSHIFT;
203 
204 	if (mdb_vread(&entry, sizeof (entry), wsp->walk_addr) == -1) {
205 		mdb_warn("failed to read freelist entry %p", wsp->walk_addr);
206 		return (WALK_DONE);
207 	}
208 	wsp->walk_addr += sizeof (entry);
209 	wsp->walk_data = (void *)(number + 1);
210 
211 	if (SM_DEBUG_DECODE(entry)) {
212 		mdb_printf("DEBUG: %3u  %10s: txg=%llu  pass=%llu\n",
213 		    number,
214 		    ddata[SM_DEBUG_ACTION_DECODE(entry)],
215 		    SM_DEBUG_TXG_DECODE(entry),
216 		    SM_DEBUG_SYNCPASS_DECODE(entry));
217 	} else {
218 		mdb_printf("Entry: %3u  offsets=%08llx-%08llx  type=%c  "
219 		    "size=%06llx", number,
220 		    SM_OFFSET_DECODE(entry) << mapshift,
221 		    (SM_OFFSET_DECODE(entry) + SM_RUN_DECODE(entry)) <<
222 		    mapshift,
223 		    SM_TYPE_DECODE(entry) == SM_ALLOC ? 'A' : 'F',
224 		    SM_RUN_DECODE(entry) << mapshift);
225 		if (verbose)
226 			mdb_printf("      (raw=%012llx)\n", entry);
227 		mdb_printf("\n");
228 	}
229 	return (WALK_NEXT);
230 }
231 
232 static int
233 mdb_dsl_dir_name(uintptr_t addr, char *buf)
234 {
235 	static int gotid;
236 	static mdb_ctf_id_t dd_id;
237 	uintptr_t dd_parent;
238 	char dd_myname[ZFS_MAX_DATASET_NAME_LEN];
239 
240 	if (!gotid) {
241 		if (mdb_ctf_lookup_by_name(ZFS_STRUCT "dsl_dir",
242 		    &dd_id) == -1) {
243 			mdb_warn("couldn't find struct dsl_dir");
244 			return (DCMD_ERR);
245 		}
246 		gotid = TRUE;
247 	}
248 	if (GETMEMBID(addr, &dd_id, dd_parent, dd_parent) ||
249 	    GETMEMBID(addr, &dd_id, dd_myname, dd_myname)) {
250 		return (DCMD_ERR);
251 	}
252 
253 	if (dd_parent) {
254 		if (mdb_dsl_dir_name(dd_parent, buf))
255 			return (DCMD_ERR);
256 		strcat(buf, "/");
257 	}
258 
259 	if (dd_myname[0])
260 		strcat(buf, dd_myname);
261 	else
262 		strcat(buf, "???");
263 
264 	return (0);
265 }
266 
267 static int
268 objset_name(uintptr_t addr, char *buf)
269 {
270 	static int gotid;
271 	static mdb_ctf_id_t os_id, ds_id;
272 	uintptr_t os_dsl_dataset;
273 	char ds_snapname[ZFS_MAX_DATASET_NAME_LEN];
274 	uintptr_t ds_dir;
275 
276 	buf[0] = '\0';
277 
278 	if (!gotid) {
279 		if (mdb_ctf_lookup_by_name(ZFS_STRUCT "objset",
280 		    &os_id) == -1) {
281 			mdb_warn("couldn't find struct objset");
282 			return (DCMD_ERR);
283 		}
284 		if (mdb_ctf_lookup_by_name(ZFS_STRUCT "dsl_dataset",
285 		    &ds_id) == -1) {
286 			mdb_warn("couldn't find struct dsl_dataset");
287 			return (DCMD_ERR);
288 		}
289 
290 		gotid = TRUE;
291 	}
292 
293 	if (GETMEMBID(addr, &os_id, os_dsl_dataset, os_dsl_dataset))
294 		return (DCMD_ERR);
295 
296 	if (os_dsl_dataset == 0) {
297 		strcat(buf, "mos");
298 		return (0);
299 	}
300 
301 	if (GETMEMBID(os_dsl_dataset, &ds_id, ds_snapname, ds_snapname) ||
302 	    GETMEMBID(os_dsl_dataset, &ds_id, ds_dir, ds_dir)) {
303 		return (DCMD_ERR);
304 	}
305 
306 	if (ds_dir && mdb_dsl_dir_name(ds_dir, buf))
307 		return (DCMD_ERR);
308 
309 	if (ds_snapname[0]) {
310 		strcat(buf, "@");
311 		strcat(buf, ds_snapname);
312 	}
313 	return (0);
314 }
315 
316 static int
317 enum_lookup(char *type, int val, const char *prefix, size_t size, char *out)
318 {
319 	const char *cp;
320 	size_t len = strlen(prefix);
321 	mdb_ctf_id_t enum_type;
322 
323 	if (mdb_ctf_lookup_by_name(type, &enum_type) != 0) {
324 		mdb_warn("Could not find enum for %s", type);
325 		return (-1);
326 	}
327 
328 	if ((cp = mdb_ctf_enum_name(enum_type, val)) != NULL) {
329 		if (strncmp(cp, prefix, len) == 0)
330 			cp += len;
331 		(void) strncpy(out, cp, size);
332 	} else {
333 		mdb_snprintf(out, size, "? (%d)", val);
334 	}
335 	return (0);
336 }
337 
338 /* ARGSUSED */
339 static int
340 zfs_params(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
341 {
342 	/*
343 	 * This table can be approximately generated by running:
344 	 * egrep "^[a-z0-9_]+ [a-z0-9_]+( =.*)?;" *.c | cut -d ' ' -f 2
345 	 */
346 	static const char *params[] = {
347 		"arc_reduce_dnlc_percent",
348 		"arc_lotsfree_percent",
349 		"zfs_dirty_data_max",
350 		"zfs_dirty_data_sync",
351 		"zfs_delay_max_ns",
352 		"zfs_delay_min_dirty_percent",
353 		"zfs_delay_scale",
354 		"zfs_vdev_max_active",
355 		"zfs_vdev_sync_read_min_active",
356 		"zfs_vdev_sync_read_max_active",
357 		"zfs_vdev_sync_write_min_active",
358 		"zfs_vdev_sync_write_max_active",
359 		"zfs_vdev_async_read_min_active",
360 		"zfs_vdev_async_read_max_active",
361 		"zfs_vdev_async_write_min_active",
362 		"zfs_vdev_async_write_max_active",
363 		"zfs_vdev_scrub_min_active",
364 		"zfs_vdev_scrub_max_active",
365 		"zfs_vdev_async_write_active_min_dirty_percent",
366 		"zfs_vdev_async_write_active_max_dirty_percent",
367 		"spa_asize_inflation",
368 		"zfs_arc_max",
369 		"zfs_arc_min",
370 		"arc_shrink_shift",
371 		"zfs_mdcomp_disable",
372 		"zfs_prefetch_disable",
373 		"zfetch_max_streams",
374 		"zfetch_min_sec_reap",
375 		"zfetch_block_cap",
376 		"zfetch_array_rd_sz",
377 		"zfs_default_bs",
378 		"zfs_default_ibs",
379 		"metaslab_aliquot",
380 		"reference_tracking_enable",
381 		"reference_history",
382 		"spa_max_replication_override",
383 		"spa_mode_global",
384 		"zfs_flags",
385 		"zfs_txg_timeout",
386 		"zfs_vdev_cache_max",
387 		"zfs_vdev_cache_size",
388 		"zfs_vdev_cache_bshift",
389 		"vdev_mirror_shift",
390 		"zfs_scrub_limit",
391 		"zfs_no_scrub_io",
392 		"zfs_no_scrub_prefetch",
393 		"zfs_vdev_aggregation_limit",
394 		"fzap_default_block_shift",
395 		"zfs_immediate_write_sz",
396 		"zfs_read_chunk_size",
397 		"zfs_nocacheflush",
398 		"zil_replay_disable",
399 		"metaslab_gang_bang",
400 		"metaslab_df_alloc_threshold",
401 		"metaslab_df_free_pct",
402 		"zio_injection_enabled",
403 		"zvol_immediate_write_sz",
404 	};
405 
406 	for (int i = 0; i < sizeof (params) / sizeof (params[0]); i++) {
407 		int sz;
408 		uint64_t val64;
409 		uint32_t *val32p = (uint32_t *)&val64;
410 
411 		sz = mdb_readvar(&val64, params[i]);
412 		if (sz == 4) {
413 			mdb_printf("%s = 0x%x\n", params[i], *val32p);
414 		} else if (sz == 8) {
415 			mdb_printf("%s = 0x%llx\n", params[i], val64);
416 		} else {
417 			mdb_warn("variable %s not found", params[i]);
418 		}
419 	}
420 
421 	return (DCMD_OK);
422 }
423 
424 /* ARGSUSED */
425 static int
426 dva(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
427 {
428 	dva_t dva;
429 	if (mdb_vread(&dva, sizeof (dva_t), addr) == -1) {
430 		mdb_warn("failed to read dva_t");
431 		return (DCMD_ERR);
432 	}
433 	mdb_printf("<%llu:%llx:%llx>\n",
434 	    (u_longlong_t)DVA_GET_VDEV(&dva),
435 	    (u_longlong_t)DVA_GET_OFFSET(&dva),
436 	    (u_longlong_t)DVA_GET_ASIZE(&dva));
437 
438 	return (DCMD_OK);
439 }
440 
441 /* ARGSUSED */
442 static int
443 blkptr(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
444 {
445 	char type[80], checksum[80], compress[80];
446 	blkptr_t blk, *bp = &blk;
447 	char buf[BP_SPRINTF_LEN];
448 
449 	if (mdb_vread(&blk, sizeof (blkptr_t), addr) == -1) {
450 		mdb_warn("failed to read blkptr_t");
451 		return (DCMD_ERR);
452 	}
453 
454 	if (enum_lookup("enum dmu_object_type", BP_GET_TYPE(bp), "DMU_OT_",
455 	    sizeof (type), type) == -1 ||
456 	    enum_lookup("enum zio_checksum", BP_GET_CHECKSUM(bp),
457 	    "ZIO_CHECKSUM_", sizeof (checksum), checksum) == -1 ||
458 	    enum_lookup("enum zio_compress", BP_GET_COMPRESS(bp),
459 	    "ZIO_COMPRESS_", sizeof (compress), compress) == -1) {
460 		mdb_warn("Could not find blkptr enumerated types");
461 		return (DCMD_ERR);
462 	}
463 
464 	SNPRINTF_BLKPTR(mdb_snprintf, '\n', buf, sizeof (buf), bp, type,
465 	    checksum, compress);
466 
467 	mdb_printf("%s\n", buf);
468 
469 	return (DCMD_OK);
470 }
471 
472 typedef struct mdb_dmu_buf_impl {
473 	struct {
474 		uint64_t db_object;
475 		uintptr_t db_data;
476 	} db;
477 	uintptr_t db_objset;
478 	uint64_t db_level;
479 	uint64_t db_blkid;
480 	struct {
481 		uint64_t rc_count;
482 	} db_holds;
483 } mdb_dmu_buf_impl_t;
484 
485 /* ARGSUSED */
486 static int
487 dbuf(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
488 {
489 	mdb_dmu_buf_impl_t db;
490 	char objectname[32];
491 	char blkidname[32];
492 	char path[ZFS_MAX_DATASET_NAME_LEN];
493 	int ptr_width = (int)(sizeof (void *)) * 2;
494 
495 	if (DCMD_HDRSPEC(flags))
496 		mdb_printf("%*s %8s %3s %9s %5s %s\n",
497 		    ptr_width, "addr", "object", "lvl", "blkid", "holds", "os");
498 
499 	if (mdb_ctf_vread(&db, ZFS_STRUCT "dmu_buf_impl", "mdb_dmu_buf_impl_t",
500 	    addr, 0) == -1)
501 		return (DCMD_ERR);
502 
503 	if (db.db.db_object == DMU_META_DNODE_OBJECT)
504 		(void) strcpy(objectname, "mdn");
505 	else
506 		(void) mdb_snprintf(objectname, sizeof (objectname), "%llx",
507 		    (u_longlong_t)db.db.db_object);
508 
509 	if (db.db_blkid == DMU_BONUS_BLKID)
510 		(void) strcpy(blkidname, "bonus");
511 	else
512 		(void) mdb_snprintf(blkidname, sizeof (blkidname), "%llx",
513 		    (u_longlong_t)db.db_blkid);
514 
515 	if (objset_name(db.db_objset, path)) {
516 		return (DCMD_ERR);
517 	}
518 
519 	mdb_printf("%*p %8s %3u %9s %5llu %s\n", ptr_width, addr,
520 	    objectname, (int)db.db_level, blkidname,
521 	    db.db_holds.rc_count, path);
522 
523 	return (DCMD_OK);
524 }
525 
526 /* ARGSUSED */
527 static int
528 dbuf_stats(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
529 {
530 #define	HISTOSZ 32
531 	uintptr_t dbp;
532 	dmu_buf_impl_t db;
533 	dbuf_hash_table_t ht;
534 	uint64_t bucket, ndbufs;
535 	uint64_t histo[HISTOSZ];
536 	uint64_t histo2[HISTOSZ];
537 	int i, maxidx;
538 
539 	if (mdb_readvar(&ht, "dbuf_hash_table") == -1) {
540 		mdb_warn("failed to read 'dbuf_hash_table'");
541 		return (DCMD_ERR);
542 	}
543 
544 	for (i = 0; i < HISTOSZ; i++) {
545 		histo[i] = 0;
546 		histo2[i] = 0;
547 	}
548 
549 	ndbufs = 0;
550 	for (bucket = 0; bucket < ht.hash_table_mask+1; bucket++) {
551 		int len;
552 
553 		if (mdb_vread(&dbp, sizeof (void *),
554 		    (uintptr_t)(ht.hash_table+bucket)) == -1) {
555 			mdb_warn("failed to read hash bucket %u at %p",
556 			    bucket, ht.hash_table+bucket);
557 			return (DCMD_ERR);
558 		}
559 
560 		len = 0;
561 		while (dbp != 0) {
562 			if (mdb_vread(&db, sizeof (dmu_buf_impl_t),
563 			    dbp) == -1) {
564 				mdb_warn("failed to read dbuf at %p", dbp);
565 				return (DCMD_ERR);
566 			}
567 			dbp = (uintptr_t)db.db_hash_next;
568 			for (i = MIN(len, HISTOSZ - 1); i >= 0; i--)
569 				histo2[i]++;
570 			len++;
571 			ndbufs++;
572 		}
573 
574 		if (len >= HISTOSZ)
575 			len = HISTOSZ-1;
576 		histo[len]++;
577 	}
578 
579 	mdb_printf("hash table has %llu buckets, %llu dbufs "
580 	    "(avg %llu buckets/dbuf)\n",
581 	    ht.hash_table_mask+1, ndbufs,
582 	    (ht.hash_table_mask+1)/ndbufs);
583 
584 	mdb_printf("\n");
585 	maxidx = 0;
586 	for (i = 0; i < HISTOSZ; i++)
587 		if (histo[i] > 0)
588 			maxidx = i;
589 	mdb_printf("hash chain length	number of buckets\n");
590 	for (i = 0; i <= maxidx; i++)
591 		mdb_printf("%u			%llu\n", i, histo[i]);
592 
593 	mdb_printf("\n");
594 	maxidx = 0;
595 	for (i = 0; i < HISTOSZ; i++)
596 		if (histo2[i] > 0)
597 			maxidx = i;
598 	mdb_printf("hash chain depth	number of dbufs\n");
599 	for (i = 0; i <= maxidx; i++)
600 		mdb_printf("%u or more		%llu	%llu%%\n",
601 		    i, histo2[i], histo2[i]*100/ndbufs);
602 
603 
604 	return (DCMD_OK);
605 }
606 
607 #define	CHAIN_END 0xffff
608 /*
609  * ::zap_leaf [-v]
610  *
611  * Print a zap_leaf_phys_t, assumed to be 16k
612  */
613 /* ARGSUSED */
614 static int
615 zap_leaf(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
616 {
617 	char buf[16*1024];
618 	int verbose = B_FALSE;
619 	int four = B_FALSE;
620 	dmu_buf_t l_dbuf;
621 	zap_leaf_t l;
622 	zap_leaf_phys_t *zlp = (void *)buf;
623 	int i;
624 
625 	if (mdb_getopts(argc, argv,
626 	    'v', MDB_OPT_SETBITS, TRUE, &verbose,
627 	    '4', MDB_OPT_SETBITS, TRUE, &four,
628 	    NULL) != argc)
629 		return (DCMD_USAGE);
630 
631 	l_dbuf.db_data = zlp;
632 	l.l_dbuf = &l_dbuf;
633 	l.l_bs = 14; /* assume 16k blocks */
634 	if (four)
635 		l.l_bs = 12;
636 
637 	if (!(flags & DCMD_ADDRSPEC)) {
638 		return (DCMD_USAGE);
639 	}
640 
641 	if (mdb_vread(buf, sizeof (buf), addr) == -1) {
642 		mdb_warn("failed to read zap_leaf_phys_t at %p", addr);
643 		return (DCMD_ERR);
644 	}
645 
646 	if (zlp->l_hdr.lh_block_type != ZBT_LEAF ||
647 	    zlp->l_hdr.lh_magic != ZAP_LEAF_MAGIC) {
648 		mdb_warn("This does not appear to be a zap_leaf_phys_t");
649 		return (DCMD_ERR);
650 	}
651 
652 	mdb_printf("zap_leaf_phys_t at %p:\n", addr);
653 	mdb_printf("    lh_prefix_len = %u\n", zlp->l_hdr.lh_prefix_len);
654 	mdb_printf("    lh_prefix = %llx\n", zlp->l_hdr.lh_prefix);
655 	mdb_printf("    lh_nentries = %u\n", zlp->l_hdr.lh_nentries);
656 	mdb_printf("    lh_nfree = %u\n", zlp->l_hdr.lh_nfree,
657 	    zlp->l_hdr.lh_nfree * 100 / (ZAP_LEAF_NUMCHUNKS(&l)));
658 	mdb_printf("    lh_freelist = %u\n", zlp->l_hdr.lh_freelist);
659 	mdb_printf("    lh_flags = %x (%s)\n", zlp->l_hdr.lh_flags,
660 	    zlp->l_hdr.lh_flags & ZLF_ENTRIES_CDSORTED ?
661 	    "ENTRIES_CDSORTED" : "");
662 
663 	if (verbose) {
664 		mdb_printf(" hash table:\n");
665 		for (i = 0; i < ZAP_LEAF_HASH_NUMENTRIES(&l); i++) {
666 			if (zlp->l_hash[i] != CHAIN_END)
667 				mdb_printf("    %u: %u\n", i, zlp->l_hash[i]);
668 		}
669 	}
670 
671 	mdb_printf(" chunks:\n");
672 	for (i = 0; i < ZAP_LEAF_NUMCHUNKS(&l); i++) {
673 		/* LINTED: alignment */
674 		zap_leaf_chunk_t *zlc = &ZAP_LEAF_CHUNK(&l, i);
675 		switch (zlc->l_entry.le_type) {
676 		case ZAP_CHUNK_FREE:
677 			if (verbose) {
678 				mdb_printf("    %u: free; lf_next = %u\n",
679 				    i, zlc->l_free.lf_next);
680 			}
681 			break;
682 		case ZAP_CHUNK_ENTRY:
683 			mdb_printf("    %u: entry\n", i);
684 			if (verbose) {
685 				mdb_printf("        le_next = %u\n",
686 				    zlc->l_entry.le_next);
687 			}
688 			mdb_printf("        le_name_chunk = %u\n",
689 			    zlc->l_entry.le_name_chunk);
690 			mdb_printf("        le_name_numints = %u\n",
691 			    zlc->l_entry.le_name_numints);
692 			mdb_printf("        le_value_chunk = %u\n",
693 			    zlc->l_entry.le_value_chunk);
694 			mdb_printf("        le_value_intlen = %u\n",
695 			    zlc->l_entry.le_value_intlen);
696 			mdb_printf("        le_value_numints = %u\n",
697 			    zlc->l_entry.le_value_numints);
698 			mdb_printf("        le_cd = %u\n",
699 			    zlc->l_entry.le_cd);
700 			mdb_printf("        le_hash = %llx\n",
701 			    zlc->l_entry.le_hash);
702 			break;
703 		case ZAP_CHUNK_ARRAY:
704 			mdb_printf("    %u: array", i);
705 			if (strisprint((char *)zlc->l_array.la_array))
706 				mdb_printf(" \"%s\"", zlc->l_array.la_array);
707 			mdb_printf("\n");
708 			if (verbose) {
709 				int j;
710 				mdb_printf("        ");
711 				for (j = 0; j < ZAP_LEAF_ARRAY_BYTES; j++) {
712 					mdb_printf("%02x ",
713 					    zlc->l_array.la_array[j]);
714 				}
715 				mdb_printf("\n");
716 			}
717 			if (zlc->l_array.la_next != CHAIN_END) {
718 				mdb_printf("        lf_next = %u\n",
719 				    zlc->l_array.la_next);
720 			}
721 			break;
722 		default:
723 			mdb_printf("    %u: undefined type %u\n",
724 			    zlc->l_entry.le_type);
725 		}
726 	}
727 
728 	return (DCMD_OK);
729 }
730 
731 typedef struct dbufs_data {
732 	mdb_ctf_id_t id;
733 	uint64_t objset;
734 	uint64_t object;
735 	uint64_t level;
736 	uint64_t blkid;
737 	char *osname;
738 } dbufs_data_t;
739 
740 #define	DBUFS_UNSET	(0xbaddcafedeadbeefULL)
741 
742 /* ARGSUSED */
743 static int
744 dbufs_cb(uintptr_t addr, const void *unknown, void *arg)
745 {
746 	dbufs_data_t *data = arg;
747 	uintptr_t objset;
748 	dmu_buf_t db;
749 	uint8_t level;
750 	uint64_t blkid;
751 	char osname[ZFS_MAX_DATASET_NAME_LEN];
752 
753 	if (GETMEMBID(addr, &data->id, db_objset, objset) ||
754 	    GETMEMBID(addr, &data->id, db, db) ||
755 	    GETMEMBID(addr, &data->id, db_level, level) ||
756 	    GETMEMBID(addr, &data->id, db_blkid, blkid)) {
757 		return (WALK_ERR);
758 	}
759 
760 	if ((data->objset == DBUFS_UNSET || data->objset == objset) &&
761 	    (data->osname == NULL || (objset_name(objset, osname) == 0 &&
762 	    strcmp(data->osname, osname) == 0)) &&
763 	    (data->object == DBUFS_UNSET || data->object == db.db_object) &&
764 	    (data->level == DBUFS_UNSET || data->level == level) &&
765 	    (data->blkid == DBUFS_UNSET || data->blkid == blkid)) {
766 		mdb_printf("%#lr\n", addr);
767 	}
768 	return (WALK_NEXT);
769 }
770 
771 /* ARGSUSED */
772 static int
773 dbufs(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
774 {
775 	dbufs_data_t data;
776 	char *object = NULL;
777 	char *blkid = NULL;
778 
779 	data.objset = data.object = data.level = data.blkid = DBUFS_UNSET;
780 	data.osname = NULL;
781 
782 	if (mdb_getopts(argc, argv,
783 	    'O', MDB_OPT_UINT64, &data.objset,
784 	    'n', MDB_OPT_STR, &data.osname,
785 	    'o', MDB_OPT_STR, &object,
786 	    'l', MDB_OPT_UINT64, &data.level,
787 	    'b', MDB_OPT_STR, &blkid) != argc) {
788 		return (DCMD_USAGE);
789 	}
790 
791 	if (object) {
792 		if (strcmp(object, "mdn") == 0) {
793 			data.object = DMU_META_DNODE_OBJECT;
794 		} else {
795 			data.object = mdb_strtoull(object);
796 		}
797 	}
798 
799 	if (blkid) {
800 		if (strcmp(blkid, "bonus") == 0) {
801 			data.blkid = DMU_BONUS_BLKID;
802 		} else {
803 			data.blkid = mdb_strtoull(blkid);
804 		}
805 	}
806 
807 	if (mdb_ctf_lookup_by_name(ZFS_STRUCT "dmu_buf_impl", &data.id) == -1) {
808 		mdb_warn("couldn't find struct dmu_buf_impl_t");
809 		return (DCMD_ERR);
810 	}
811 
812 	if (mdb_walk("dmu_buf_impl_t", dbufs_cb, &data) != 0) {
813 		mdb_warn("can't walk dbufs");
814 		return (DCMD_ERR);
815 	}
816 
817 	return (DCMD_OK);
818 }
819 
820 typedef struct abuf_find_data {
821 	dva_t dva;
822 	mdb_ctf_id_t id;
823 } abuf_find_data_t;
824 
825 /* ARGSUSED */
826 static int
827 abuf_find_cb(uintptr_t addr, const void *unknown, void *arg)
828 {
829 	abuf_find_data_t *data = arg;
830 	dva_t dva;
831 
832 	if (GETMEMBID(addr, &data->id, b_dva, dva)) {
833 		return (WALK_ERR);
834 	}
835 
836 	if (dva.dva_word[0] == data->dva.dva_word[0] &&
837 	    dva.dva_word[1] == data->dva.dva_word[1]) {
838 		mdb_printf("%#lr\n", addr);
839 	}
840 	return (WALK_NEXT);
841 }
842 
843 /* ARGSUSED */
844 static int
845 abuf_find(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
846 {
847 	abuf_find_data_t data;
848 	GElf_Sym sym;
849 	int i;
850 	const char *syms[] = {
851 		"ARC_mru",
852 		"ARC_mru_ghost",
853 		"ARC_mfu",
854 		"ARC_mfu_ghost",
855 	};
856 
857 	if (argc != 2)
858 		return (DCMD_USAGE);
859 
860 	for (i = 0; i < 2; i ++) {
861 		switch (argv[i].a_type) {
862 		case MDB_TYPE_STRING:
863 			data.dva.dva_word[i] = mdb_strtoull(argv[i].a_un.a_str);
864 			break;
865 		case MDB_TYPE_IMMEDIATE:
866 			data.dva.dva_word[i] = argv[i].a_un.a_val;
867 			break;
868 		default:
869 			return (DCMD_USAGE);
870 		}
871 	}
872 
873 	if (mdb_ctf_lookup_by_name(ZFS_STRUCT "arc_buf_hdr", &data.id) == -1) {
874 		mdb_warn("couldn't find struct arc_buf_hdr");
875 		return (DCMD_ERR);
876 	}
877 
878 	for (i = 0; i < sizeof (syms) / sizeof (syms[0]); i++) {
879 		if (mdb_lookup_by_obj(ZFS_OBJ_NAME, syms[i], &sym)) {
880 			mdb_warn("can't find symbol %s", syms[i]);
881 			return (DCMD_ERR);
882 		}
883 
884 		if (mdb_pwalk("list", abuf_find_cb, &data, sym.st_value) != 0) {
885 			mdb_warn("can't walk %s", syms[i]);
886 			return (DCMD_ERR);
887 		}
888 	}
889 
890 	return (DCMD_OK);
891 }
892 
893 
894 typedef struct dbgmsg_arg {
895 	boolean_t da_verbose;
896 	boolean_t da_address;
897 } dbgmsg_arg_t;
898 
899 /* ARGSUSED */
900 static int
901 dbgmsg_cb(uintptr_t addr, const void *unknown, void *arg)
902 {
903 	static mdb_ctf_id_t id;
904 	static boolean_t gotid;
905 	static ulong_t off;
906 
907 	dbgmsg_arg_t *da = arg;
908 	time_t timestamp;
909 	char buf[1024];
910 
911 	if (!gotid) {
912 		if (mdb_ctf_lookup_by_name(ZFS_STRUCT "zfs_dbgmsg", &id) ==
913 		    -1) {
914 			mdb_warn("couldn't find struct zfs_dbgmsg");
915 			return (WALK_ERR);
916 		}
917 		gotid = TRUE;
918 		if (mdb_ctf_offsetof(id, "zdm_msg", &off) == -1) {
919 			mdb_warn("couldn't find zdm_msg");
920 			return (WALK_ERR);
921 		}
922 		off /= 8;
923 	}
924 
925 
926 	if (GETMEMBID(addr, &id, zdm_timestamp, timestamp)) {
927 		return (WALK_ERR);
928 	}
929 
930 	if (mdb_readstr(buf, sizeof (buf), addr + off) == -1) {
931 		mdb_warn("failed to read zdm_msg at %p\n", addr + off);
932 		return (DCMD_ERR);
933 	}
934 
935 	if (da->da_address)
936 		mdb_printf("%p ", addr);
937 	if (da->da_verbose)
938 		mdb_printf("%Y ", timestamp);
939 
940 	mdb_printf("%s\n", buf);
941 
942 	if (da->da_verbose)
943 		(void) mdb_call_dcmd("whatis", addr, DCMD_ADDRSPEC, 0, NULL);
944 
945 	return (WALK_NEXT);
946 }
947 
948 /* ARGSUSED */
949 static int
950 dbgmsg(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
951 {
952 	GElf_Sym sym;
953 	dbgmsg_arg_t da = { 0 };
954 
955 	if (mdb_getopts(argc, argv,
956 	    'v', MDB_OPT_SETBITS, B_TRUE, &da.da_verbose,
957 	    'a', MDB_OPT_SETBITS, B_TRUE, &da.da_address,
958 	    NULL) != argc)
959 		return (DCMD_USAGE);
960 
961 	if (mdb_lookup_by_obj(ZFS_OBJ_NAME, "zfs_dbgmsgs", &sym)) {
962 		mdb_warn("can't find zfs_dbgmsgs");
963 		return (DCMD_ERR);
964 	}
965 
966 	if (mdb_pwalk("list", dbgmsg_cb, &da, sym.st_value) != 0) {
967 		mdb_warn("can't walk zfs_dbgmsgs");
968 		return (DCMD_ERR);
969 	}
970 
971 	return (DCMD_OK);
972 }
973 
974 /*ARGSUSED*/
975 static int
976 arc_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
977 {
978 	kstat_named_t *stats;
979 	GElf_Sym sym;
980 	int nstats, i;
981 	uint_t opt_a = FALSE;
982 	uint_t opt_b = FALSE;
983 	uint_t shift = 0;
984 	const char *suffix;
985 
986 	static const char *bytestats[] = {
987 		"p", "c", "c_min", "c_max", "size", "duplicate_buffers_size",
988 		"arc_meta_used", "arc_meta_limit", "arc_meta_max",
989 		"arc_meta_min", "hdr_size", "data_size", "metadata_size",
990 		"other_size", "anon_size", "anon_evictable_data",
991 		"anon_evictable_metadata", "mru_size", "mru_evictable_data",
992 		"mru_evictable_metadata", "mru_ghost_size",
993 		"mru_ghost_evictable_data", "mru_ghost_evictable_metadata",
994 		"mfu_size", "mfu_evictable_data", "mfu_evictable_metadata",
995 		"mfu_ghost_size", "mfu_ghost_evictable_data",
996 		"mfu_ghost_evictable_metadata", "evict_l2_cached",
997 		"evict_l2_eligible", "evict_l2_ineligible", "l2_read_bytes",
998 		"l2_write_bytes", "l2_size", "l2_asize", "l2_hdr_size",
999 		"compressed_size", "uncompressed_size", "overhead_size",
1000 		NULL
1001 	};
1002 
1003 	static const char *extras[] = {
1004 		"arc_no_grow", "arc_tempreserve",
1005 		NULL
1006 	};
1007 
1008 	if (mdb_lookup_by_obj(ZFS_OBJ_NAME, "arc_stats", &sym) == -1) {
1009 		mdb_warn("failed to find 'arc_stats'");
1010 		return (DCMD_ERR);
1011 	}
1012 
1013 	stats = mdb_zalloc(sym.st_size, UM_SLEEP | UM_GC);
1014 
1015 	if (mdb_vread(stats, sym.st_size, sym.st_value) == -1) {
1016 		mdb_warn("couldn't read 'arc_stats' at %p", sym.st_value);
1017 		return (DCMD_ERR);
1018 	}
1019 
1020 	nstats = sym.st_size / sizeof (kstat_named_t);
1021 
1022 	/* NB: -a / opt_a are ignored for backwards compatability */
1023 	if (mdb_getopts(argc, argv,
1024 	    'a', MDB_OPT_SETBITS, TRUE, &opt_a,
1025 	    'b', MDB_OPT_SETBITS, TRUE, &opt_b,
1026 	    'k', MDB_OPT_SETBITS, 10, &shift,
1027 	    'm', MDB_OPT_SETBITS, 20, &shift,
1028 	    'g', MDB_OPT_SETBITS, 30, &shift,
1029 	    NULL) != argc)
1030 		return (DCMD_USAGE);
1031 
1032 	if (!opt_b && !shift)
1033 		shift = 20;
1034 
1035 	switch (shift) {
1036 	case 0:
1037 		suffix = "B";
1038 		break;
1039 	case 10:
1040 		suffix = "KB";
1041 		break;
1042 	case 20:
1043 		suffix = "MB";
1044 		break;
1045 	case 30:
1046 		suffix = "GB";
1047 		break;
1048 	default:
1049 		suffix = "XX";
1050 	}
1051 
1052 	for (i = 0; i < nstats; i++) {
1053 		int j;
1054 		boolean_t bytes = B_FALSE;
1055 
1056 		for (j = 0; bytestats[j]; j++) {
1057 			if (strcmp(stats[i].name, bytestats[j]) == 0) {
1058 				bytes = B_TRUE;
1059 				break;
1060 			}
1061 		}
1062 
1063 		if (bytes) {
1064 			mdb_printf("%-25s = %9llu %s\n", stats[i].name,
1065 			    stats[i].value.ui64 >> shift, suffix);
1066 		} else {
1067 			mdb_printf("%-25s = %9llu\n", stats[i].name,
1068 			    stats[i].value.ui64);
1069 		}
1070 	}
1071 
1072 	for (i = 0; extras[i]; i++) {
1073 		uint64_t buf;
1074 
1075 		if (mdb_lookup_by_obj(ZFS_OBJ_NAME, extras[i], &sym) == -1) {
1076 			mdb_warn("failed to find '%s'", extras[i]);
1077 			return (DCMD_ERR);
1078 		}
1079 
1080 		if (sym.st_size != sizeof (uint64_t) &&
1081 		    sym.st_size != sizeof (uint32_t)) {
1082 			mdb_warn("expected scalar for variable '%s'\n",
1083 			    extras[i]);
1084 			return (DCMD_ERR);
1085 		}
1086 
1087 		if (mdb_vread(&buf, sym.st_size, sym.st_value) == -1) {
1088 			mdb_warn("couldn't read '%s'", extras[i]);
1089 			return (DCMD_ERR);
1090 		}
1091 
1092 		mdb_printf("%-25s = ", extras[i]);
1093 
1094 		/* NB: all the 64-bit extras happen to be byte counts */
1095 		if (sym.st_size == sizeof (uint64_t))
1096 			mdb_printf("%9llu %s\n", buf >> shift, suffix);
1097 
1098 		if (sym.st_size == sizeof (uint32_t))
1099 			mdb_printf("%9d\n", *((uint32_t *)&buf));
1100 	}
1101 	return (DCMD_OK);
1102 }
1103 
1104 typedef struct mdb_spa_print {
1105 	pool_state_t spa_state;
1106 	char spa_name[ZFS_MAX_DATASET_NAME_LEN];
1107 	uintptr_t spa_normal_class;
1108 } mdb_spa_print_t;
1109 
1110 
1111 const char histo_stars[] = "****************************************";
1112 const int histo_width = sizeof (histo_stars) - 1;
1113 
1114 static void
1115 dump_histogram(const uint64_t *histo, int size, int offset)
1116 {
1117 	int i;
1118 	int minidx = size - 1;
1119 	int maxidx = 0;
1120 	uint64_t max = 0;
1121 
1122 	for (i = 0; i < size; i++) {
1123 		if (histo[i] > max)
1124 			max = histo[i];
1125 		if (histo[i] > 0 && i > maxidx)
1126 			maxidx = i;
1127 		if (histo[i] > 0 && i < minidx)
1128 			minidx = i;
1129 	}
1130 
1131 	if (max < histo_width)
1132 		max = histo_width;
1133 
1134 	for (i = minidx; i <= maxidx; i++) {
1135 		mdb_printf("%3u: %6llu %s\n",
1136 		    i + offset, (u_longlong_t)histo[i],
1137 		    &histo_stars[(max - histo[i]) * histo_width / max]);
1138 	}
1139 }
1140 
1141 typedef struct mdb_metaslab_class {
1142 	uint64_t mc_histogram[RANGE_TREE_HISTOGRAM_SIZE];
1143 } mdb_metaslab_class_t;
1144 
1145 /*
1146  * spa_class_histogram(uintptr_t class_addr)
1147  *
1148  * Prints free space histogram for a device class
1149  *
1150  * Returns DCMD_OK, or DCMD_ERR.
1151  */
1152 static int
1153 spa_class_histogram(uintptr_t class_addr)
1154 {
1155 	mdb_metaslab_class_t mc;
1156 	if (mdb_ctf_vread(&mc, "metaslab_class_t",
1157 	    "mdb_metaslab_class_t", class_addr, 0) == -1)
1158 		return (DCMD_ERR);
1159 
1160 	mdb_inc_indent(4);
1161 	dump_histogram(mc.mc_histogram, RANGE_TREE_HISTOGRAM_SIZE, 0);
1162 	mdb_dec_indent(4);
1163 	return (DCMD_OK);
1164 }
1165 
1166 /*
1167  * ::spa
1168  *
1169  *	-c	Print configuration information as well
1170  *	-v	Print vdev state
1171  *	-e	Print vdev error stats
1172  *	-m	Print vdev metaslab info
1173  *	-M	print vdev metaslab group info
1174  *	-h	Print histogram info (must be combined with -m or -M)
1175  *
1176  * Print a summarized spa_t.  When given no arguments, prints out a table of all
1177  * active pools on the system.
1178  */
1179 /* ARGSUSED */
1180 static int
1181 spa_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1182 {
1183 	const char *statetab[] = { "ACTIVE", "EXPORTED", "DESTROYED",
1184 		"SPARE", "L2CACHE", "UNINIT", "UNAVAIL", "POTENTIAL" };
1185 	const char *state;
1186 	int spa_flags = 0;
1187 
1188 	if (mdb_getopts(argc, argv,
1189 	    'c', MDB_OPT_SETBITS, SPA_FLAG_CONFIG, &spa_flags,
1190 	    'v', MDB_OPT_SETBITS, SPA_FLAG_VDEVS, &spa_flags,
1191 	    'e', MDB_OPT_SETBITS, SPA_FLAG_ERRORS, &spa_flags,
1192 	    'M', MDB_OPT_SETBITS, SPA_FLAG_METASLAB_GROUPS, &spa_flags,
1193 	    'm', MDB_OPT_SETBITS, SPA_FLAG_METASLABS, &spa_flags,
1194 	    'h', MDB_OPT_SETBITS, SPA_FLAG_HISTOGRAMS, &spa_flags,
1195 	    NULL) != argc)
1196 		return (DCMD_USAGE);
1197 
1198 	if (!(flags & DCMD_ADDRSPEC)) {
1199 		if (mdb_walk_dcmd("spa", "spa", argc, argv) == -1) {
1200 			mdb_warn("can't walk spa");
1201 			return (DCMD_ERR);
1202 		}
1203 
1204 		return (DCMD_OK);
1205 	}
1206 
1207 	if (flags & DCMD_PIPE_OUT) {
1208 		mdb_printf("%#lr\n", addr);
1209 		return (DCMD_OK);
1210 	}
1211 
1212 	if (DCMD_HDRSPEC(flags))
1213 		mdb_printf("%<u>%-?s %9s %-*s%</u>\n", "ADDR", "STATE",
1214 		    sizeof (uintptr_t) == 4 ? 60 : 52, "NAME");
1215 
1216 	mdb_spa_print_t spa;
1217 	if (mdb_ctf_vread(&spa, "spa_t", "mdb_spa_print_t", addr, 0) == -1)
1218 		return (DCMD_ERR);
1219 
1220 	if (spa.spa_state < 0 || spa.spa_state > POOL_STATE_UNAVAIL)
1221 		state = "UNKNOWN";
1222 	else
1223 		state = statetab[spa.spa_state];
1224 
1225 	mdb_printf("%0?p %9s %s\n", addr, state, spa.spa_name);
1226 	if (spa_flags & SPA_FLAG_HISTOGRAMS)
1227 		spa_class_histogram(spa.spa_normal_class);
1228 
1229 	if (spa_flags & SPA_FLAG_CONFIG) {
1230 		mdb_printf("\n");
1231 		mdb_inc_indent(4);
1232 		if (mdb_call_dcmd("spa_config", addr, flags, 0,
1233 		    NULL) != DCMD_OK)
1234 			return (DCMD_ERR);
1235 		mdb_dec_indent(4);
1236 	}
1237 
1238 	if (spa_flags & SPA_FLAG_ALL_VDEV) {
1239 		mdb_arg_t v;
1240 		char opts[100] = "-";
1241 		int args =
1242 		    (spa_flags | SPA_FLAG_VDEVS) == SPA_FLAG_VDEVS ? 0 : 1;
1243 
1244 		if (spa_flags & SPA_FLAG_ERRORS)
1245 			strcat(opts, "e");
1246 		if (spa_flags & SPA_FLAG_METASLABS)
1247 			strcat(opts, "m");
1248 		if (spa_flags & SPA_FLAG_METASLAB_GROUPS)
1249 			strcat(opts, "M");
1250 		if (spa_flags & SPA_FLAG_HISTOGRAMS)
1251 			strcat(opts, "h");
1252 
1253 		v.a_type = MDB_TYPE_STRING;
1254 		v.a_un.a_str = opts;
1255 
1256 		mdb_printf("\n");
1257 		mdb_inc_indent(4);
1258 		if (mdb_call_dcmd("spa_vdevs", addr, flags, args,
1259 		    &v) != DCMD_OK)
1260 			return (DCMD_ERR);
1261 		mdb_dec_indent(4);
1262 	}
1263 
1264 	return (DCMD_OK);
1265 }
1266 
1267 typedef struct mdb_spa_config_spa {
1268 	uintptr_t spa_config;
1269 } mdb_spa_config_spa_t;
1270 
1271 /*
1272  * ::spa_config
1273  *
1274  * Given a spa_t, print the configuration information stored in spa_config.
1275  * Since it's just an nvlist, format it as an indented list of name=value pairs.
1276  * We simply read the value of spa_config and pass off to ::nvlist.
1277  */
1278 /* ARGSUSED */
1279 static int
1280 spa_print_config(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1281 {
1282 	mdb_spa_config_spa_t spa;
1283 
1284 	if (argc != 0 || !(flags & DCMD_ADDRSPEC))
1285 		return (DCMD_USAGE);
1286 
1287 	if (mdb_ctf_vread(&spa, ZFS_STRUCT "spa", "mdb_spa_config_spa_t",
1288 	    addr, 0) == -1)
1289 		return (DCMD_ERR);
1290 
1291 	if (spa.spa_config == 0) {
1292 		mdb_printf("(none)\n");
1293 		return (DCMD_OK);
1294 	}
1295 
1296 	return (mdb_call_dcmd("nvlist", spa.spa_config, flags,
1297 	    0, NULL));
1298 }
1299 
1300 
1301 
1302 typedef struct mdb_range_tree {
1303 	uint64_t rt_space;
1304 } mdb_range_tree_t;
1305 
1306 typedef struct mdb_metaslab_group {
1307 	uint64_t mg_fragmentation;
1308 	uint64_t mg_histogram[RANGE_TREE_HISTOGRAM_SIZE];
1309 	uintptr_t mg_vd;
1310 } mdb_metaslab_group_t;
1311 
1312 typedef struct mdb_metaslab {
1313 	uint64_t ms_id;
1314 	uint64_t ms_start;
1315 	uint64_t ms_size;
1316 	int64_t ms_deferspace;
1317 	uint64_t ms_fragmentation;
1318 	uint64_t ms_weight;
1319 	uintptr_t ms_alloctree[TXG_SIZE];
1320 	uintptr_t ms_freeingtree;
1321 	uintptr_t ms_freedtree;
1322 	uintptr_t ms_tree;
1323 	uintptr_t ms_sm;
1324 } mdb_metaslab_t;
1325 
1326 typedef struct mdb_space_map_phys_t {
1327 	uint64_t smp_alloc;
1328 	uint64_t smp_histogram[SPACE_MAP_HISTOGRAM_SIZE];
1329 } mdb_space_map_phys_t;
1330 
1331 typedef struct mdb_space_map {
1332 	uint64_t sm_size;
1333 	uint8_t sm_shift;
1334 	uint64_t sm_alloc;
1335 	uintptr_t sm_phys;
1336 } mdb_space_map_t;
1337 
1338 typedef struct mdb_vdev {
1339 	uintptr_t vdev_path;
1340 	uintptr_t vdev_ms;
1341 	uintptr_t vdev_ops;
1342 	uint64_t vdev_ms_count;
1343 	uint64_t vdev_id;
1344 	vdev_stat_t vdev_stat;
1345 } mdb_vdev_t;
1346 
1347 typedef struct mdb_vdev_ops {
1348 	char vdev_op_type[16];
1349 } mdb_vdev_ops_t;
1350 
1351 static int
1352 metaslab_stats(uintptr_t addr, int spa_flags)
1353 {
1354 	mdb_vdev_t vdev;
1355 	uintptr_t *vdev_ms;
1356 
1357 	if (mdb_ctf_vread(&vdev, "vdev_t", "mdb_vdev_t",
1358 	    (uintptr_t)addr, 0) == -1) {
1359 		mdb_warn("failed to read vdev at %p\n", addr);
1360 		return (DCMD_ERR);
1361 	}
1362 
1363 	mdb_inc_indent(4);
1364 	mdb_printf("%<u>%-?s %6s %20s %10s %9s%</u>\n", "ADDR", "ID",
1365 	    "OFFSET", "FREE", "FRAGMENTATION");
1366 
1367 	vdev_ms = mdb_alloc(vdev.vdev_ms_count * sizeof (void *),
1368 	    UM_SLEEP | UM_GC);
1369 	if (mdb_vread(vdev_ms, vdev.vdev_ms_count * sizeof (void *),
1370 	    (uintptr_t)vdev.vdev_ms) == -1) {
1371 		mdb_warn("failed to read vdev_ms at %p\n", vdev.vdev_ms);
1372 		return (DCMD_ERR);
1373 	}
1374 
1375 	for (int m = 0; m < vdev.vdev_ms_count; m++) {
1376 		mdb_metaslab_t ms;
1377 		mdb_space_map_t sm = { 0 };
1378 		char free[NICENUM_BUFLEN];
1379 
1380 		if (mdb_ctf_vread(&ms, "metaslab_t", "mdb_metaslab_t",
1381 		    (uintptr_t)vdev_ms[m], 0) == -1)
1382 			return (DCMD_ERR);
1383 
1384 		if (ms.ms_sm != NULL &&
1385 		    mdb_ctf_vread(&sm, "space_map_t", "mdb_space_map_t",
1386 		    ms.ms_sm, 0) == -1)
1387 			return (DCMD_ERR);
1388 
1389 		mdb_nicenum(ms.ms_size - sm.sm_alloc, free);
1390 
1391 		mdb_printf("%0?p %6llu %20llx %10s ", vdev_ms[m], ms.ms_id,
1392 		    ms.ms_start, free);
1393 		if (ms.ms_fragmentation == ZFS_FRAG_INVALID)
1394 			mdb_printf("%9s\n", "-");
1395 		else
1396 			mdb_printf("%9llu%%\n", ms.ms_fragmentation);
1397 
1398 		if ((spa_flags & SPA_FLAG_HISTOGRAMS) && ms.ms_sm != NULL) {
1399 			mdb_space_map_phys_t smp;
1400 
1401 			if (sm.sm_phys == NULL)
1402 				continue;
1403 
1404 			(void) mdb_ctf_vread(&smp, "space_map_phys_t",
1405 			    "mdb_space_map_phys_t", sm.sm_phys, 0);
1406 
1407 			dump_histogram(smp.smp_histogram,
1408 			    SPACE_MAP_HISTOGRAM_SIZE, sm.sm_shift);
1409 		}
1410 	}
1411 	mdb_dec_indent(4);
1412 	return (DCMD_OK);
1413 }
1414 
1415 static int
1416 metaslab_group_stats(uintptr_t addr, int spa_flags)
1417 {
1418 	mdb_metaslab_group_t mg;
1419 	if (mdb_ctf_vread(&mg, "metaslab_group_t", "mdb_metaslab_group_t",
1420 	    (uintptr_t)addr, 0) == -1) {
1421 		mdb_warn("failed to read vdev_mg at %p\n", addr);
1422 		return (DCMD_ERR);
1423 	}
1424 
1425 	mdb_inc_indent(4);
1426 	mdb_printf("%<u>%-?s %15s%</u>\n", "ADDR", "FRAGMENTATION");
1427 	if (mg.mg_fragmentation == ZFS_FRAG_INVALID)
1428 		mdb_printf("%0?p %15s\n", addr, "-");
1429 	else
1430 		mdb_printf("%0?p %15llu%%\n", addr, mg.mg_fragmentation);
1431 
1432 	if (spa_flags & SPA_FLAG_HISTOGRAMS)
1433 		dump_histogram(mg.mg_histogram, RANGE_TREE_HISTOGRAM_SIZE, 0);
1434 	mdb_dec_indent(4);
1435 	return (DCMD_OK);
1436 }
1437 
1438 /*
1439  * ::vdev
1440  *
1441  * Print out a summarized vdev_t, in the following form:
1442  *
1443  * ADDR             STATE	AUX            DESC
1444  * fffffffbcde23df0 HEALTHY	-              /dev/dsk/c0t0d0
1445  *
1446  * If '-r' is specified, recursively visit all children.
1447  *
1448  * With '-e', the statistics associated with the vdev are printed as well.
1449  */
1450 static int
1451 do_print_vdev(uintptr_t addr, int flags, int depth, boolean_t recursive,
1452     int spa_flags)
1453 {
1454 	vdev_t vdev;
1455 	char desc[MAXNAMELEN];
1456 	int c, children;
1457 	uintptr_t *child;
1458 	const char *state, *aux;
1459 
1460 	if (mdb_vread(&vdev, sizeof (vdev), (uintptr_t)addr) == -1) {
1461 		mdb_warn("failed to read vdev_t at %p\n", (uintptr_t)addr);
1462 		return (DCMD_ERR);
1463 	}
1464 
1465 	if (flags & DCMD_PIPE_OUT) {
1466 		mdb_printf("%#lr\n", addr);
1467 	} else {
1468 		if (vdev.vdev_path != NULL) {
1469 			if (mdb_readstr(desc, sizeof (desc),
1470 			    (uintptr_t)vdev.vdev_path) == -1) {
1471 				mdb_warn("failed to read vdev_path at %p\n",
1472 				    vdev.vdev_path);
1473 				return (DCMD_ERR);
1474 			}
1475 		} else if (vdev.vdev_ops != NULL) {
1476 			vdev_ops_t ops;
1477 			if (mdb_vread(&ops, sizeof (ops),
1478 			    (uintptr_t)vdev.vdev_ops) == -1) {
1479 				mdb_warn("failed to read vdev_ops at %p\n",
1480 				    vdev.vdev_ops);
1481 				return (DCMD_ERR);
1482 			}
1483 			(void) strcpy(desc, ops.vdev_op_type);
1484 		} else {
1485 			(void) strcpy(desc, "<unknown>");
1486 		}
1487 
1488 		if (depth == 0 && DCMD_HDRSPEC(flags))
1489 			mdb_printf("%<u>%-?s %-9s %-12s %-*s%</u>\n",
1490 			    "ADDR", "STATE", "AUX",
1491 			    sizeof (uintptr_t) == 4 ? 43 : 35,
1492 			    "DESCRIPTION");
1493 
1494 		mdb_printf("%0?p ", addr);
1495 
1496 		switch (vdev.vdev_state) {
1497 		case VDEV_STATE_CLOSED:
1498 			state = "CLOSED";
1499 			break;
1500 		case VDEV_STATE_OFFLINE:
1501 			state = "OFFLINE";
1502 			break;
1503 		case VDEV_STATE_CANT_OPEN:
1504 			state = "CANT_OPEN";
1505 			break;
1506 		case VDEV_STATE_DEGRADED:
1507 			state = "DEGRADED";
1508 			break;
1509 		case VDEV_STATE_HEALTHY:
1510 			state = "HEALTHY";
1511 			break;
1512 		case VDEV_STATE_REMOVED:
1513 			state = "REMOVED";
1514 			break;
1515 		case VDEV_STATE_FAULTED:
1516 			state = "FAULTED";
1517 			break;
1518 		default:
1519 			state = "UNKNOWN";
1520 			break;
1521 		}
1522 
1523 		switch (vdev.vdev_stat.vs_aux) {
1524 		case VDEV_AUX_NONE:
1525 			aux = "-";
1526 			break;
1527 		case VDEV_AUX_OPEN_FAILED:
1528 			aux = "OPEN_FAILED";
1529 			break;
1530 		case VDEV_AUX_CORRUPT_DATA:
1531 			aux = "CORRUPT_DATA";
1532 			break;
1533 		case VDEV_AUX_NO_REPLICAS:
1534 			aux = "NO_REPLICAS";
1535 			break;
1536 		case VDEV_AUX_BAD_GUID_SUM:
1537 			aux = "BAD_GUID_SUM";
1538 			break;
1539 		case VDEV_AUX_TOO_SMALL:
1540 			aux = "TOO_SMALL";
1541 			break;
1542 		case VDEV_AUX_BAD_LABEL:
1543 			aux = "BAD_LABEL";
1544 			break;
1545 		case VDEV_AUX_VERSION_NEWER:
1546 			aux = "VERS_NEWER";
1547 			break;
1548 		case VDEV_AUX_VERSION_OLDER:
1549 			aux = "VERS_OLDER";
1550 			break;
1551 		case VDEV_AUX_UNSUP_FEAT:
1552 			aux = "UNSUP_FEAT";
1553 			break;
1554 		case VDEV_AUX_SPARED:
1555 			aux = "SPARED";
1556 			break;
1557 		case VDEV_AUX_ERR_EXCEEDED:
1558 			aux = "ERR_EXCEEDED";
1559 			break;
1560 		case VDEV_AUX_IO_FAILURE:
1561 			aux = "IO_FAILURE";
1562 			break;
1563 		case VDEV_AUX_BAD_LOG:
1564 			aux = "BAD_LOG";
1565 			break;
1566 		case VDEV_AUX_EXTERNAL:
1567 			aux = "EXTERNAL";
1568 			break;
1569 		case VDEV_AUX_SPLIT_POOL:
1570 			aux = "SPLIT_POOL";
1571 			break;
1572 		case VDEV_AUX_CHILDREN_OFFLINE:
1573 			aux = "CHILDREN_OFFLINE";
1574 			break;
1575 		default:
1576 			aux = "UNKNOWN";
1577 			break;
1578 		}
1579 
1580 		mdb_printf("%-9s %-12s %*s%s\n", state, aux, depth, "", desc);
1581 
1582 		if (spa_flags & SPA_FLAG_ERRORS) {
1583 			vdev_stat_t *vs = &vdev.vdev_stat;
1584 			int i;
1585 
1586 			mdb_inc_indent(4);
1587 			mdb_printf("\n");
1588 			mdb_printf("%<u>       %12s %12s %12s %12s "
1589 			    "%12s%</u>\n", "READ", "WRITE", "FREE", "CLAIM",
1590 			    "IOCTL");
1591 			mdb_printf("OPS     ");
1592 			for (i = 1; i < ZIO_TYPES; i++)
1593 				mdb_printf("%11#llx%s", vs->vs_ops[i],
1594 				    i == ZIO_TYPES - 1 ? "" : "  ");
1595 			mdb_printf("\n");
1596 			mdb_printf("BYTES   ");
1597 			for (i = 1; i < ZIO_TYPES; i++)
1598 				mdb_printf("%11#llx%s", vs->vs_bytes[i],
1599 				    i == ZIO_TYPES - 1 ? "" : "  ");
1600 
1601 
1602 			mdb_printf("\n");
1603 			mdb_printf("EREAD    %10#llx\n", vs->vs_read_errors);
1604 			mdb_printf("EWRITE   %10#llx\n", vs->vs_write_errors);
1605 			mdb_printf("ECKSUM   %10#llx\n",
1606 			    vs->vs_checksum_errors);
1607 			mdb_dec_indent(4);
1608 			mdb_printf("\n");
1609 		}
1610 
1611 		if (spa_flags & SPA_FLAG_METASLAB_GROUPS &&
1612 		    vdev.vdev_mg != NULL) {
1613 			metaslab_group_stats((uintptr_t)vdev.vdev_mg,
1614 			    spa_flags);
1615 		}
1616 		if (spa_flags & SPA_FLAG_METASLABS && vdev.vdev_ms != NULL) {
1617 			metaslab_stats((uintptr_t)addr, spa_flags);
1618 		}
1619 	}
1620 
1621 	children = vdev.vdev_children;
1622 
1623 	if (children == 0 || !recursive)
1624 		return (DCMD_OK);
1625 
1626 	child = mdb_alloc(children * sizeof (void *), UM_SLEEP | UM_GC);
1627 	if (mdb_vread(child, children * sizeof (void *),
1628 	    (uintptr_t)vdev.vdev_child) == -1) {
1629 		mdb_warn("failed to read vdev children at %p", vdev.vdev_child);
1630 		return (DCMD_ERR);
1631 	}
1632 
1633 	for (c = 0; c < children; c++) {
1634 		if (do_print_vdev(child[c], flags, depth + 2, recursive,
1635 		    spa_flags)) {
1636 			return (DCMD_ERR);
1637 		}
1638 	}
1639 
1640 	return (DCMD_OK);
1641 }
1642 
1643 static int
1644 vdev_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1645 {
1646 	uint64_t depth = 0;
1647 	boolean_t recursive = B_FALSE;
1648 	int spa_flags = 0;
1649 
1650 	if (mdb_getopts(argc, argv,
1651 	    'e', MDB_OPT_SETBITS, SPA_FLAG_ERRORS, &spa_flags,
1652 	    'm', MDB_OPT_SETBITS, SPA_FLAG_METASLABS, &spa_flags,
1653 	    'M', MDB_OPT_SETBITS, SPA_FLAG_METASLAB_GROUPS, &spa_flags,
1654 	    'h', MDB_OPT_SETBITS, SPA_FLAG_HISTOGRAMS, &spa_flags,
1655 	    'r', MDB_OPT_SETBITS, TRUE, &recursive,
1656 	    'd', MDB_OPT_UINT64, &depth, NULL) != argc)
1657 		return (DCMD_USAGE);
1658 
1659 	if (!(flags & DCMD_ADDRSPEC)) {
1660 		mdb_warn("no vdev_t address given\n");
1661 		return (DCMD_ERR);
1662 	}
1663 
1664 	return (do_print_vdev(addr, flags, (int)depth, recursive, spa_flags));
1665 }
1666 
1667 typedef struct mdb_metaslab_alloc_trace {
1668 	uintptr_t mat_mg;
1669 	uintptr_t mat_msp;
1670 	uint64_t mat_size;
1671 	uint64_t mat_weight;
1672 	uint64_t mat_offset;
1673 	uint32_t mat_dva_id;
1674 } mdb_metaslab_alloc_trace_t;
1675 
1676 static void
1677 metaslab_print_weight(uint64_t weight)
1678 {
1679 	char buf[100];
1680 
1681 	if (WEIGHT_IS_SPACEBASED(weight)) {
1682 		mdb_nicenum(
1683 		    weight & ~(METASLAB_ACTIVE_MASK | METASLAB_WEIGHT_TYPE),
1684 		    buf);
1685 	} else {
1686 		char size[NICENUM_BUFLEN];
1687 		mdb_nicenum(1ULL << WEIGHT_GET_INDEX(weight), size);
1688 		(void) mdb_snprintf(buf, sizeof (buf), "%llu x %s",
1689 		    WEIGHT_GET_COUNT(weight), size);
1690 	}
1691 	mdb_printf("%11s ", buf);
1692 }
1693 
1694 /* ARGSUSED */
1695 static int
1696 metaslab_weight(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1697 {
1698 	uint64_t weight = 0;
1699 	char active;
1700 
1701 	if (argc == 0 && (flags & DCMD_ADDRSPEC)) {
1702 		if (mdb_vread(&weight, sizeof (uint64_t), addr) == -1) {
1703 			mdb_warn("failed to read weight at %p\n", addr);
1704 			return (DCMD_ERR);
1705 		}
1706 	} else if (argc == 1 && !(flags & DCMD_ADDRSPEC)) {
1707 		weight = (argv[0].a_type == MDB_TYPE_IMMEDIATE) ?
1708 		    argv[0].a_un.a_val : mdb_strtoull(argv[0].a_un.a_str);
1709 	} else {
1710 		return (DCMD_USAGE);
1711 	}
1712 
1713 	if (DCMD_HDRSPEC(flags)) {
1714 		mdb_printf("%<u>%-6s %9s %9s%</u>\n",
1715 		    "ACTIVE", "ALGORITHM", "WEIGHT");
1716 	}
1717 
1718 	if (weight & METASLAB_WEIGHT_PRIMARY)
1719 		active = 'P';
1720 	else if (weight & METASLAB_WEIGHT_SECONDARY)
1721 		active = 'S';
1722 	else
1723 		active = '-';
1724 	mdb_printf("%6c %8s ", active,
1725 	    WEIGHT_IS_SPACEBASED(weight) ? "SPACE" : "SEGMENT");
1726 	metaslab_print_weight(weight);
1727 	mdb_printf("\n");
1728 
1729 	return (DCMD_OK);
1730 }
1731 
1732 /* ARGSUSED */
1733 static int
1734 metaslab_trace(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1735 {
1736 	mdb_metaslab_alloc_trace_t mat;
1737 	mdb_metaslab_group_t mg = { 0 };
1738 	char result_type[100];
1739 
1740 	if (mdb_ctf_vread(&mat, "metaslab_alloc_trace_t",
1741 	    "mdb_metaslab_alloc_trace_t", addr, 0) == -1) {
1742 		return (DCMD_ERR);
1743 	}
1744 
1745 	if (!(flags & DCMD_PIPE_OUT) && DCMD_HDRSPEC(flags)) {
1746 		mdb_printf("%<u>%6s %6s %8s %11s %18s %18s%</u>\n",
1747 		    "MSID", "DVA", "ASIZE", "WEIGHT", "RESULT", "VDEV");
1748 	}
1749 
1750 	if (mat.mat_msp != NULL) {
1751 		mdb_metaslab_t ms;
1752 
1753 		if (mdb_ctf_vread(&ms, "metaslab_t", "mdb_metaslab_t",
1754 		    mat.mat_msp, 0) == -1) {
1755 			return (DCMD_ERR);
1756 		}
1757 		mdb_printf("%6llu ", ms.ms_id);
1758 	} else {
1759 		mdb_printf("%6s ", "-");
1760 	}
1761 
1762 	mdb_printf("%6d %8llx ", mat.mat_dva_id, mat.mat_size);
1763 
1764 	metaslab_print_weight(mat.mat_weight);
1765 
1766 	if ((int64_t)mat.mat_offset < 0) {
1767 		if (enum_lookup("enum trace_alloc_type", mat.mat_offset,
1768 		    "TRACE_", sizeof (result_type), result_type) == -1) {
1769 			mdb_warn("Could not find enum for trace_alloc_type");
1770 			return (DCMD_ERR);
1771 		}
1772 		mdb_printf("%18s ", result_type);
1773 	} else {
1774 		mdb_printf("%<b>%18llx%</b> ", mat.mat_offset);
1775 	}
1776 
1777 	if (mat.mat_mg != NULL &&
1778 	    mdb_ctf_vread(&mg, "metaslab_group_t", "mdb_metaslab_group_t",
1779 	    mat.mat_mg, 0) == -1) {
1780 		return (DCMD_ERR);
1781 	}
1782 
1783 	if (mg.mg_vd != NULL) {
1784 		mdb_vdev_t vdev;
1785 		char desc[MAXNAMELEN];
1786 
1787 		if (mdb_ctf_vread(&vdev, "vdev_t", "mdb_vdev_t",
1788 		    mg.mg_vd, 0) == -1) {
1789 			return (DCMD_ERR);
1790 		}
1791 
1792 		if (vdev.vdev_path != NULL) {
1793 			char path[MAXNAMELEN];
1794 
1795 			if (mdb_readstr(path, sizeof (path),
1796 			    vdev.vdev_path) == -1) {
1797 				mdb_warn("failed to read vdev_path at %p\n",
1798 				    vdev.vdev_path);
1799 				return (DCMD_ERR);
1800 			}
1801 			char *slash;
1802 			if ((slash = strrchr(path, '/')) != NULL) {
1803 				strcpy(desc, slash + 1);
1804 			} else {
1805 				strcpy(desc, path);
1806 			}
1807 		} else if (vdev.vdev_ops != NULL) {
1808 			mdb_vdev_ops_t ops;
1809 			if (mdb_ctf_vread(&ops, "vdev_ops_t", "mdb_vdev_ops_t",
1810 			    vdev.vdev_ops, 0) == -1) {
1811 				mdb_warn("failed to read vdev_ops at %p\n",
1812 				    vdev.vdev_ops);
1813 				return (DCMD_ERR);
1814 			}
1815 			(void) mdb_snprintf(desc, sizeof (desc),
1816 			    "%s-%llu", ops.vdev_op_type, vdev.vdev_id);
1817 		} else {
1818 			(void) strcpy(desc, "<unknown>");
1819 		}
1820 		mdb_printf("%18s\n", desc);
1821 	}
1822 
1823 	return (DCMD_OK);
1824 }
1825 
1826 typedef struct metaslab_walk_data {
1827 	uint64_t mw_numvdevs;
1828 	uintptr_t *mw_vdevs;
1829 	int mw_curvdev;
1830 	uint64_t mw_nummss;
1831 	uintptr_t *mw_mss;
1832 	int mw_curms;
1833 } metaslab_walk_data_t;
1834 
1835 static int
1836 metaslab_walk_step(mdb_walk_state_t *wsp)
1837 {
1838 	metaslab_walk_data_t *mw = wsp->walk_data;
1839 	metaslab_t ms;
1840 	uintptr_t msp;
1841 
1842 	if (mw->mw_curvdev >= mw->mw_numvdevs)
1843 		return (WALK_DONE);
1844 
1845 	if (mw->mw_mss == NULL) {
1846 		uintptr_t mssp;
1847 		uintptr_t vdevp;
1848 
1849 		ASSERT(mw->mw_curms == 0);
1850 		ASSERT(mw->mw_nummss == 0);
1851 
1852 		vdevp = mw->mw_vdevs[mw->mw_curvdev];
1853 		if (GETMEMB(vdevp, "vdev", vdev_ms, mssp) ||
1854 		    GETMEMB(vdevp, "vdev", vdev_ms_count, mw->mw_nummss)) {
1855 			return (WALK_ERR);
1856 		}
1857 
1858 		mw->mw_mss = mdb_alloc(mw->mw_nummss * sizeof (void*),
1859 		    UM_SLEEP | UM_GC);
1860 		if (mdb_vread(mw->mw_mss, mw->mw_nummss * sizeof (void*),
1861 		    mssp) == -1) {
1862 			mdb_warn("failed to read vdev_ms at %p", mssp);
1863 			return (WALK_ERR);
1864 		}
1865 	}
1866 
1867 	if (mw->mw_curms >= mw->mw_nummss) {
1868 		mw->mw_mss = NULL;
1869 		mw->mw_curms = 0;
1870 		mw->mw_nummss = 0;
1871 		mw->mw_curvdev++;
1872 		return (WALK_NEXT);
1873 	}
1874 
1875 	msp = mw->mw_mss[mw->mw_curms];
1876 	if (mdb_vread(&ms, sizeof (metaslab_t), msp) == -1) {
1877 		mdb_warn("failed to read metaslab_t at %p", msp);
1878 		return (WALK_ERR);
1879 	}
1880 
1881 	mw->mw_curms++;
1882 
1883 	return (wsp->walk_callback(msp, &ms, wsp->walk_cbdata));
1884 }
1885 
1886 static int
1887 metaslab_walk_init(mdb_walk_state_t *wsp)
1888 {
1889 	metaslab_walk_data_t *mw;
1890 	uintptr_t root_vdevp;
1891 	uintptr_t childp;
1892 
1893 	if (wsp->walk_addr == NULL) {
1894 		mdb_warn("must supply address of spa_t\n");
1895 		return (WALK_ERR);
1896 	}
1897 
1898 	mw = mdb_zalloc(sizeof (metaslab_walk_data_t), UM_SLEEP | UM_GC);
1899 
1900 	if (GETMEMB(wsp->walk_addr, "spa", spa_root_vdev, root_vdevp) ||
1901 	    GETMEMB(root_vdevp, "vdev", vdev_children, mw->mw_numvdevs) ||
1902 	    GETMEMB(root_vdevp, "vdev", vdev_child, childp)) {
1903 		return (DCMD_ERR);
1904 	}
1905 
1906 	mw->mw_vdevs = mdb_alloc(mw->mw_numvdevs * sizeof (void *),
1907 	    UM_SLEEP | UM_GC);
1908 	if (mdb_vread(mw->mw_vdevs, mw->mw_numvdevs * sizeof (void *),
1909 	    childp) == -1) {
1910 		mdb_warn("failed to read root vdev children at %p", childp);
1911 		return (DCMD_ERR);
1912 	}
1913 
1914 	wsp->walk_data = mw;
1915 
1916 	return (WALK_NEXT);
1917 }
1918 
1919 typedef struct mdb_spa {
1920 	uintptr_t spa_dsl_pool;
1921 	uintptr_t spa_root_vdev;
1922 } mdb_spa_t;
1923 
1924 typedef struct mdb_dsl_pool {
1925 	uintptr_t dp_root_dir;
1926 } mdb_dsl_pool_t;
1927 
1928 typedef struct mdb_dsl_dir {
1929 	uintptr_t dd_dbuf;
1930 	int64_t dd_space_towrite[TXG_SIZE];
1931 } mdb_dsl_dir_t;
1932 
1933 typedef struct mdb_dsl_dir_phys {
1934 	uint64_t dd_used_bytes;
1935 	uint64_t dd_compressed_bytes;
1936 	uint64_t dd_uncompressed_bytes;
1937 } mdb_dsl_dir_phys_t;
1938 
1939 typedef struct space_data {
1940 	uint64_t ms_alloctree[TXG_SIZE];
1941 	uint64_t ms_freeingtree;
1942 	uint64_t ms_freedtree;
1943 	uint64_t ms_tree;
1944 	int64_t ms_deferspace;
1945 	uint64_t avail;
1946 	uint64_t nowavail;
1947 } space_data_t;
1948 
1949 /* ARGSUSED */
1950 static int
1951 space_cb(uintptr_t addr, const void *unknown, void *arg)
1952 {
1953 	space_data_t *sd = arg;
1954 	mdb_metaslab_t ms;
1955 	mdb_range_tree_t rt;
1956 	mdb_space_map_t sm = { 0 };
1957 	mdb_space_map_phys_t smp = { 0 };
1958 	int i;
1959 
1960 	if (mdb_ctf_vread(&ms, "metaslab_t", "mdb_metaslab_t",
1961 	    addr, 0) == -1)
1962 		return (WALK_ERR);
1963 
1964 	for (i = 0; i < TXG_SIZE; i++) {
1965 		if (mdb_ctf_vread(&rt, "range_tree_t",
1966 		    "mdb_range_tree_t", ms.ms_alloctree[i], 0) == -1)
1967 			return (WALK_ERR);
1968 
1969 		sd->ms_alloctree[i] += rt.rt_space;
1970 
1971 	}
1972 
1973 	if (mdb_ctf_vread(&rt, "range_tree_t",
1974 	    "mdb_range_tree_t", ms.ms_freeingtree, 0) == -1)
1975 		return (WALK_ERR);
1976 	sd->ms_freeingtree += rt.rt_space;
1977 
1978 	if (mdb_ctf_vread(&rt, "range_tree_t",
1979 	    "mdb_range_tree_t", ms.ms_freedtree, 0) == -1)
1980 		return (WALK_ERR);
1981 	sd->ms_freedtree += rt.rt_space;
1982 
1983 	if (mdb_ctf_vread(&rt, "range_tree_t",
1984 	    "mdb_range_tree_t", ms.ms_tree, 0) == -1)
1985 		return (WALK_ERR);
1986 	sd->ms_tree += rt.rt_space;
1987 
1988 	if (ms.ms_sm != NULL &&
1989 	    mdb_ctf_vread(&sm, "space_map_t",
1990 	    "mdb_space_map_t", ms.ms_sm, 0) == -1)
1991 		return (WALK_ERR);
1992 
1993 	if (sm.sm_phys != NULL) {
1994 		(void) mdb_ctf_vread(&smp, "space_map_phys_t",
1995 		    "mdb_space_map_phys_t", sm.sm_phys, 0);
1996 	}
1997 
1998 	sd->ms_deferspace += ms.ms_deferspace;
1999 	sd->avail += sm.sm_size - sm.sm_alloc;
2000 	sd->nowavail += sm.sm_size - smp.smp_alloc;
2001 
2002 	return (WALK_NEXT);
2003 }
2004 
2005 /*
2006  * ::spa_space [-b]
2007  *
2008  * Given a spa_t, print out it's on-disk space usage and in-core
2009  * estimates of future usage.  If -b is given, print space in bytes.
2010  * Otherwise print in megabytes.
2011  */
2012 /* ARGSUSED */
2013 static int
2014 spa_space(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2015 {
2016 	mdb_spa_t spa;
2017 	mdb_dsl_pool_t dp;
2018 	mdb_dsl_dir_t dd;
2019 	mdb_dmu_buf_impl_t db;
2020 	mdb_dsl_dir_phys_t dsp;
2021 	space_data_t sd;
2022 	int shift = 20;
2023 	char *suffix = "M";
2024 	int bytes = B_FALSE;
2025 
2026 	if (mdb_getopts(argc, argv, 'b', MDB_OPT_SETBITS, TRUE, &bytes, NULL) !=
2027 	    argc)
2028 		return (DCMD_USAGE);
2029 	if (!(flags & DCMD_ADDRSPEC))
2030 		return (DCMD_USAGE);
2031 
2032 	if (bytes) {
2033 		shift = 0;
2034 		suffix = "";
2035 	}
2036 
2037 	if (mdb_ctf_vread(&spa, ZFS_STRUCT "spa", "mdb_spa_t",
2038 	    addr, 0) == -1 ||
2039 	    mdb_ctf_vread(&dp, ZFS_STRUCT "dsl_pool", "mdb_dsl_pool_t",
2040 	    spa.spa_dsl_pool, 0) == -1 ||
2041 	    mdb_ctf_vread(&dd, ZFS_STRUCT "dsl_dir", "mdb_dsl_dir_t",
2042 	    dp.dp_root_dir, 0) == -1 ||
2043 	    mdb_ctf_vread(&db, ZFS_STRUCT "dmu_buf_impl", "mdb_dmu_buf_impl_t",
2044 	    dd.dd_dbuf, 0) == -1 ||
2045 	    mdb_ctf_vread(&dsp, ZFS_STRUCT "dsl_dir_phys",
2046 	    "mdb_dsl_dir_phys_t", db.db.db_data, 0) == -1) {
2047 		return (DCMD_ERR);
2048 	}
2049 
2050 	mdb_printf("dd_space_towrite = %llu%s %llu%s %llu%s %llu%s\n",
2051 	    dd.dd_space_towrite[0] >> shift, suffix,
2052 	    dd.dd_space_towrite[1] >> shift, suffix,
2053 	    dd.dd_space_towrite[2] >> shift, suffix,
2054 	    dd.dd_space_towrite[3] >> shift, suffix);
2055 
2056 	mdb_printf("dd_phys.dd_used_bytes = %llu%s\n",
2057 	    dsp.dd_used_bytes >> shift, suffix);
2058 	mdb_printf("dd_phys.dd_compressed_bytes = %llu%s\n",
2059 	    dsp.dd_compressed_bytes >> shift, suffix);
2060 	mdb_printf("dd_phys.dd_uncompressed_bytes = %llu%s\n",
2061 	    dsp.dd_uncompressed_bytes >> shift, suffix);
2062 
2063 	bzero(&sd, sizeof (sd));
2064 	if (mdb_pwalk("metaslab", space_cb, &sd, addr) != 0) {
2065 		mdb_warn("can't walk metaslabs");
2066 		return (DCMD_ERR);
2067 	}
2068 
2069 	mdb_printf("ms_allocmap = %llu%s %llu%s %llu%s %llu%s\n",
2070 	    sd.ms_alloctree[0] >> shift, suffix,
2071 	    sd.ms_alloctree[1] >> shift, suffix,
2072 	    sd.ms_alloctree[2] >> shift, suffix,
2073 	    sd.ms_alloctree[3] >> shift, suffix);
2074 	mdb_printf("ms_freeingtree = %llu%s\n",
2075 	    sd.ms_freeingtree >> shift, suffix);
2076 	mdb_printf("ms_freedtree = %llu%s\n",
2077 	    sd.ms_freedtree >> shift, suffix);
2078 	mdb_printf("ms_tree = %llu%s\n",
2079 	    sd.ms_tree >> shift, suffix);
2080 	mdb_printf("ms_deferspace = %llu%s\n",
2081 	    sd.ms_deferspace >> shift, suffix);
2082 	mdb_printf("last synced avail = %llu%s\n",
2083 	    sd.avail >> shift, suffix);
2084 	mdb_printf("current syncing avail = %llu%s\n",
2085 	    sd.nowavail >> shift, suffix);
2086 
2087 	return (DCMD_OK);
2088 }
2089 
2090 typedef struct mdb_spa_aux_vdev {
2091 	int sav_count;
2092 	uintptr_t sav_vdevs;
2093 } mdb_spa_aux_vdev_t;
2094 
2095 typedef struct mdb_spa_vdevs {
2096 	uintptr_t spa_root_vdev;
2097 	mdb_spa_aux_vdev_t spa_l2cache;
2098 	mdb_spa_aux_vdev_t spa_spares;
2099 } mdb_spa_vdevs_t;
2100 
2101 static int
2102 spa_print_aux(mdb_spa_aux_vdev_t *sav, uint_t flags, mdb_arg_t *v,
2103     const char *name)
2104 {
2105 	uintptr_t *aux;
2106 	size_t len;
2107 	int ret, i;
2108 
2109 	/*
2110 	 * Iterate over aux vdevs and print those out as well.  This is a
2111 	 * little annoying because we don't have a root vdev to pass to ::vdev.
2112 	 * Instead, we print a single line and then call it for each child
2113 	 * vdev.
2114 	 */
2115 	if (sav->sav_count != 0) {
2116 		v[1].a_type = MDB_TYPE_STRING;
2117 		v[1].a_un.a_str = "-d";
2118 		v[2].a_type = MDB_TYPE_IMMEDIATE;
2119 		v[2].a_un.a_val = 2;
2120 
2121 		len = sav->sav_count * sizeof (uintptr_t);
2122 		aux = mdb_alloc(len, UM_SLEEP);
2123 		if (mdb_vread(aux, len, sav->sav_vdevs) == -1) {
2124 			mdb_free(aux, len);
2125 			mdb_warn("failed to read l2cache vdevs at %p",
2126 			    sav->sav_vdevs);
2127 			return (DCMD_ERR);
2128 		}
2129 
2130 		mdb_printf("%-?s %-9s %-12s %s\n", "-", "-", "-", name);
2131 
2132 		for (i = 0; i < sav->sav_count; i++) {
2133 			ret = mdb_call_dcmd("vdev", aux[i], flags, 3, v);
2134 			if (ret != DCMD_OK) {
2135 				mdb_free(aux, len);
2136 				return (ret);
2137 			}
2138 		}
2139 
2140 		mdb_free(aux, len);
2141 	}
2142 
2143 	return (0);
2144 }
2145 
2146 /*
2147  * ::spa_vdevs
2148  *
2149  *	-e	Include error stats
2150  *	-m	Include metaslab information
2151  *	-M	Include metaslab group information
2152  *	-h	Include histogram information (requires -m or -M)
2153  *
2154  * Print out a summarized list of vdevs for the given spa_t.
2155  * This is accomplished by invoking "::vdev -re" on the root vdev, as well as
2156  * iterating over the cache devices.
2157  */
2158 /* ARGSUSED */
2159 static int
2160 spa_vdevs(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2161 {
2162 	mdb_arg_t v[3];
2163 	int ret;
2164 	char opts[100] = "-r";
2165 	int spa_flags = 0;
2166 
2167 	if (mdb_getopts(argc, argv,
2168 	    'e', MDB_OPT_SETBITS, SPA_FLAG_ERRORS, &spa_flags,
2169 	    'm', MDB_OPT_SETBITS, SPA_FLAG_METASLABS, &spa_flags,
2170 	    'M', MDB_OPT_SETBITS, SPA_FLAG_METASLAB_GROUPS, &spa_flags,
2171 	    'h', MDB_OPT_SETBITS, SPA_FLAG_HISTOGRAMS, &spa_flags,
2172 	    NULL) != argc)
2173 		return (DCMD_USAGE);
2174 
2175 	if (!(flags & DCMD_ADDRSPEC))
2176 		return (DCMD_USAGE);
2177 
2178 	mdb_spa_vdevs_t spa;
2179 	if (mdb_ctf_vread(&spa, "spa_t", "mdb_spa_vdevs_t", addr, 0) == -1)
2180 		return (DCMD_ERR);
2181 
2182 	/*
2183 	 * Unitialized spa_t structures can have a NULL root vdev.
2184 	 */
2185 	if (spa.spa_root_vdev == NULL) {
2186 		mdb_printf("no associated vdevs\n");
2187 		return (DCMD_OK);
2188 	}
2189 
2190 	if (spa_flags & SPA_FLAG_ERRORS)
2191 		strcat(opts, "e");
2192 	if (spa_flags & SPA_FLAG_METASLABS)
2193 		strcat(opts, "m");
2194 	if (spa_flags & SPA_FLAG_METASLAB_GROUPS)
2195 		strcat(opts, "M");
2196 	if (spa_flags & SPA_FLAG_HISTOGRAMS)
2197 		strcat(opts, "h");
2198 
2199 	v[0].a_type = MDB_TYPE_STRING;
2200 	v[0].a_un.a_str = opts;
2201 
2202 	ret = mdb_call_dcmd("vdev", (uintptr_t)spa.spa_root_vdev,
2203 	    flags, 1, v);
2204 	if (ret != DCMD_OK)
2205 		return (ret);
2206 
2207 	if (spa_print_aux(&spa.spa_l2cache, flags, v, "cache") != 0 ||
2208 	    spa_print_aux(&spa.spa_spares, flags, v, "spares") != 0)
2209 		return (DCMD_ERR);
2210 
2211 	return (DCMD_OK);
2212 }
2213 
2214 /*
2215  * ::zio
2216  *
2217  * Print a summary of zio_t and all its children.  This is intended to display a
2218  * zio tree, and hence we only pick the most important pieces of information for
2219  * the main summary.  More detailed information can always be found by doing a
2220  * '::print zio' on the underlying zio_t.  The columns we display are:
2221  *
2222  *	ADDRESS  TYPE  STAGE  WAITER  TIME_ELAPSED
2223  *
2224  * The 'address' column is indented by one space for each depth level as we
2225  * descend down the tree.
2226  */
2227 
2228 #define	ZIO_MAXINDENT	7
2229 #define	ZIO_MAXWIDTH	(sizeof (uintptr_t) * 2 + ZIO_MAXINDENT)
2230 #define	ZIO_WALK_SELF	0
2231 #define	ZIO_WALK_CHILD	1
2232 #define	ZIO_WALK_PARENT	2
2233 
2234 typedef struct zio_print_args {
2235 	int	zpa_current_depth;
2236 	int	zpa_min_depth;
2237 	int	zpa_max_depth;
2238 	int	zpa_type;
2239 	uint_t	zpa_flags;
2240 } zio_print_args_t;
2241 
2242 typedef struct mdb_zio {
2243 	enum zio_type io_type;
2244 	enum zio_stage io_stage;
2245 	uintptr_t io_waiter;
2246 	uintptr_t io_spa;
2247 	struct {
2248 		struct {
2249 			uintptr_t list_next;
2250 		} list_head;
2251 	} io_parent_list;
2252 	int io_error;
2253 } mdb_zio_t;
2254 
2255 typedef struct mdb_zio_timestamp {
2256 	hrtime_t io_timestamp;
2257 } mdb_zio_timestamp_t;
2258 
2259 static int zio_child_cb(uintptr_t addr, const void *unknown, void *arg);
2260 
2261 static int
2262 zio_print_cb(uintptr_t addr, zio_print_args_t *zpa)
2263 {
2264 	mdb_ctf_id_t type_enum, stage_enum;
2265 	int indent = zpa->zpa_current_depth;
2266 	const char *type, *stage;
2267 	uintptr_t laddr;
2268 	mdb_zio_t zio;
2269 	mdb_zio_timestamp_t zio_timestamp = { 0 };
2270 
2271 	if (mdb_ctf_vread(&zio, ZFS_STRUCT "zio", "mdb_zio_t", addr, 0) == -1)
2272 		return (WALK_ERR);
2273 	(void) mdb_ctf_vread(&zio_timestamp, ZFS_STRUCT "zio",
2274 	    "mdb_zio_timestamp_t", addr, MDB_CTF_VREAD_QUIET);
2275 
2276 	if (indent > ZIO_MAXINDENT)
2277 		indent = ZIO_MAXINDENT;
2278 
2279 	if (mdb_ctf_lookup_by_name("enum zio_type", &type_enum) == -1 ||
2280 	    mdb_ctf_lookup_by_name("enum zio_stage", &stage_enum) == -1) {
2281 		mdb_warn("failed to lookup zio enums");
2282 		return (WALK_ERR);
2283 	}
2284 
2285 	if ((type = mdb_ctf_enum_name(type_enum, zio.io_type)) != NULL)
2286 		type += sizeof ("ZIO_TYPE_") - 1;
2287 	else
2288 		type = "?";
2289 
2290 	if (zio.io_error == 0) {
2291 		stage = mdb_ctf_enum_name(stage_enum, zio.io_stage);
2292 		if (stage != NULL)
2293 			stage += sizeof ("ZIO_STAGE_") - 1;
2294 		else
2295 			stage = "?";
2296 	} else {
2297 		stage = "FAILED";
2298 	}
2299 
2300 	if (zpa->zpa_current_depth >= zpa->zpa_min_depth) {
2301 		if (zpa->zpa_flags & DCMD_PIPE_OUT) {
2302 			mdb_printf("%?p\n", addr);
2303 		} else {
2304 			mdb_printf("%*s%-*p %-5s %-16s ", indent, "",
2305 			    ZIO_MAXWIDTH - indent, addr, type, stage);
2306 			if (zio.io_waiter != 0)
2307 				mdb_printf("%-16lx ", zio.io_waiter);
2308 			else
2309 				mdb_printf("%-16s ", "-");
2310 #ifdef _KERNEL
2311 			if (zio_timestamp.io_timestamp != 0) {
2312 				mdb_printf("%llums", (mdb_gethrtime() -
2313 				    zio_timestamp.io_timestamp) /
2314 				    1000000);
2315 			} else {
2316 				mdb_printf("%-12s ", "-");
2317 			}
2318 #else
2319 			mdb_printf("%-12s ", "-");
2320 #endif
2321 			mdb_printf("\n");
2322 		}
2323 	}
2324 
2325 	if (zpa->zpa_current_depth >= zpa->zpa_max_depth)
2326 		return (WALK_NEXT);
2327 
2328 	if (zpa->zpa_type == ZIO_WALK_PARENT)
2329 		laddr = addr + mdb_ctf_offsetof_by_name(ZFS_STRUCT "zio",
2330 		    "io_parent_list");
2331 	else
2332 		laddr = addr + mdb_ctf_offsetof_by_name(ZFS_STRUCT "zio",
2333 		    "io_child_list");
2334 
2335 	zpa->zpa_current_depth++;
2336 	if (mdb_pwalk("list", zio_child_cb, zpa, laddr) != 0) {
2337 		mdb_warn("failed to walk zio_t children at %p\n", laddr);
2338 		return (WALK_ERR);
2339 	}
2340 	zpa->zpa_current_depth--;
2341 
2342 	return (WALK_NEXT);
2343 }
2344 
2345 /* ARGSUSED */
2346 static int
2347 zio_child_cb(uintptr_t addr, const void *unknown, void *arg)
2348 {
2349 	zio_link_t zl;
2350 	uintptr_t ziop;
2351 	zio_print_args_t *zpa = arg;
2352 
2353 	if (mdb_vread(&zl, sizeof (zl), addr) == -1) {
2354 		mdb_warn("failed to read zio_link_t at %p", addr);
2355 		return (WALK_ERR);
2356 	}
2357 
2358 	if (zpa->zpa_type == ZIO_WALK_PARENT)
2359 		ziop = (uintptr_t)zl.zl_parent;
2360 	else
2361 		ziop = (uintptr_t)zl.zl_child;
2362 
2363 	return (zio_print_cb(ziop, zpa));
2364 }
2365 
2366 /* ARGSUSED */
2367 static int
2368 zio_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2369 {
2370 	zio_print_args_t zpa = { 0 };
2371 
2372 	if (!(flags & DCMD_ADDRSPEC))
2373 		return (DCMD_USAGE);
2374 
2375 	if (mdb_getopts(argc, argv,
2376 	    'r', MDB_OPT_SETBITS, INT_MAX, &zpa.zpa_max_depth,
2377 	    'c', MDB_OPT_SETBITS, ZIO_WALK_CHILD, &zpa.zpa_type,
2378 	    'p', MDB_OPT_SETBITS, ZIO_WALK_PARENT, &zpa.zpa_type,
2379 	    NULL) != argc)
2380 		return (DCMD_USAGE);
2381 
2382 	zpa.zpa_flags = flags;
2383 	if (zpa.zpa_max_depth != 0) {
2384 		if (zpa.zpa_type == ZIO_WALK_SELF)
2385 			zpa.zpa_type = ZIO_WALK_CHILD;
2386 	} else if (zpa.zpa_type != ZIO_WALK_SELF) {
2387 		zpa.zpa_min_depth = 1;
2388 		zpa.zpa_max_depth = 1;
2389 	}
2390 
2391 	if (!(flags & DCMD_PIPE_OUT) && DCMD_HDRSPEC(flags)) {
2392 		mdb_printf("%<u>%-*s %-5s %-16s %-16s %-12s%</u>\n",
2393 		    ZIO_MAXWIDTH, "ADDRESS", "TYPE", "STAGE", "WAITER",
2394 		    "TIME_ELAPSED");
2395 	}
2396 
2397 	if (zio_print_cb(addr, &zpa) != WALK_NEXT)
2398 		return (DCMD_ERR);
2399 
2400 	return (DCMD_OK);
2401 }
2402 
2403 /*
2404  * [addr]::zio_state
2405  *
2406  * Print a summary of all zio_t structures on the system, or for a particular
2407  * pool.  This is equivalent to '::walk zio_root | ::zio'.
2408  */
2409 /*ARGSUSED*/
2410 static int
2411 zio_state(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2412 {
2413 	/*
2414 	 * MDB will remember the last address of the pipeline, so if we don't
2415 	 * zero this we'll end up trying to walk zio structures for a
2416 	 * non-existent spa_t.
2417 	 */
2418 	if (!(flags & DCMD_ADDRSPEC))
2419 		addr = 0;
2420 
2421 	return (mdb_pwalk_dcmd("zio_root", "zio", argc, argv, addr));
2422 }
2423 
2424 typedef struct mdb_multilist {
2425 	uint64_t ml_num_sublists;
2426 	uintptr_t ml_sublists;
2427 } mdb_multilist_t;
2428 
2429 typedef struct multilist_walk_data {
2430 	uint64_t mwd_idx;
2431 	mdb_multilist_t mwd_ml;
2432 } multilist_walk_data_t;
2433 
2434 /* ARGSUSED */
2435 static int
2436 multilist_print_cb(uintptr_t addr, const void *unknown, void *arg)
2437 {
2438 	mdb_printf("%#lr\n", addr);
2439 	return (WALK_NEXT);
2440 }
2441 
2442 static int
2443 multilist_walk_step(mdb_walk_state_t *wsp)
2444 {
2445 	multilist_walk_data_t *mwd = wsp->walk_data;
2446 
2447 	if (mwd->mwd_idx >= mwd->mwd_ml.ml_num_sublists)
2448 		return (WALK_DONE);
2449 
2450 	wsp->walk_addr = mwd->mwd_ml.ml_sublists +
2451 	    mdb_ctf_sizeof_by_name("multilist_sublist_t") * mwd->mwd_idx +
2452 	    mdb_ctf_offsetof_by_name("multilist_sublist_t", "mls_list");
2453 
2454 	mdb_pwalk("list", multilist_print_cb, (void*)NULL, wsp->walk_addr);
2455 	mwd->mwd_idx++;
2456 
2457 	return (WALK_NEXT);
2458 }
2459 
2460 static int
2461 multilist_walk_init(mdb_walk_state_t *wsp)
2462 {
2463 	multilist_walk_data_t *mwd;
2464 
2465 	if (wsp->walk_addr == NULL) {
2466 		mdb_warn("must supply address of multilist_t\n");
2467 		return (WALK_ERR);
2468 	}
2469 
2470 	mwd = mdb_zalloc(sizeof (multilist_walk_data_t), UM_SLEEP | UM_GC);
2471 	if (mdb_ctf_vread(&mwd->mwd_ml, "multilist_t", "mdb_multilist_t",
2472 	    wsp->walk_addr, 0) == -1) {
2473 		return (WALK_ERR);
2474 	}
2475 
2476 	if (mwd->mwd_ml.ml_num_sublists == 0 ||
2477 	    mwd->mwd_ml.ml_sublists == NULL) {
2478 		mdb_warn("invalid or uninitialized multilist at %#lx\n",
2479 		    wsp->walk_addr);
2480 		return (WALK_ERR);
2481 	}
2482 
2483 	wsp->walk_data = mwd;
2484 	return (WALK_NEXT);
2485 }
2486 
2487 typedef struct mdb_txg_list {
2488 	size_t		tl_offset;
2489 	uintptr_t	tl_head[TXG_SIZE];
2490 } mdb_txg_list_t;
2491 
2492 typedef struct txg_list_walk_data {
2493 	uintptr_t lw_head[TXG_SIZE];
2494 	int	lw_txgoff;
2495 	int	lw_maxoff;
2496 	size_t	lw_offset;
2497 	void	*lw_obj;
2498 } txg_list_walk_data_t;
2499 
2500 static int
2501 txg_list_walk_init_common(mdb_walk_state_t *wsp, int txg, int maxoff)
2502 {
2503 	txg_list_walk_data_t *lwd;
2504 	mdb_txg_list_t list;
2505 	int i;
2506 
2507 	lwd = mdb_alloc(sizeof (txg_list_walk_data_t), UM_SLEEP | UM_GC);
2508 	if (mdb_ctf_vread(&list, "txg_list_t", "mdb_txg_list_t", wsp->walk_addr,
2509 	    0) == -1) {
2510 		mdb_warn("failed to read txg_list_t at %#lx", wsp->walk_addr);
2511 		return (WALK_ERR);
2512 	}
2513 
2514 	for (i = 0; i < TXG_SIZE; i++)
2515 		lwd->lw_head[i] = list.tl_head[i];
2516 	lwd->lw_offset = list.tl_offset;
2517 	lwd->lw_obj = mdb_alloc(lwd->lw_offset + sizeof (txg_node_t),
2518 	    UM_SLEEP | UM_GC);
2519 	lwd->lw_txgoff = txg;
2520 	lwd->lw_maxoff = maxoff;
2521 
2522 	wsp->walk_addr = lwd->lw_head[lwd->lw_txgoff];
2523 	wsp->walk_data = lwd;
2524 
2525 	return (WALK_NEXT);
2526 }
2527 
2528 static int
2529 txg_list_walk_init(mdb_walk_state_t *wsp)
2530 {
2531 	return (txg_list_walk_init_common(wsp, 0, TXG_SIZE-1));
2532 }
2533 
2534 static int
2535 txg_list0_walk_init(mdb_walk_state_t *wsp)
2536 {
2537 	return (txg_list_walk_init_common(wsp, 0, 0));
2538 }
2539 
2540 static int
2541 txg_list1_walk_init(mdb_walk_state_t *wsp)
2542 {
2543 	return (txg_list_walk_init_common(wsp, 1, 1));
2544 }
2545 
2546 static int
2547 txg_list2_walk_init(mdb_walk_state_t *wsp)
2548 {
2549 	return (txg_list_walk_init_common(wsp, 2, 2));
2550 }
2551 
2552 static int
2553 txg_list3_walk_init(mdb_walk_state_t *wsp)
2554 {
2555 	return (txg_list_walk_init_common(wsp, 3, 3));
2556 }
2557 
2558 static int
2559 txg_list_walk_step(mdb_walk_state_t *wsp)
2560 {
2561 	txg_list_walk_data_t *lwd = wsp->walk_data;
2562 	uintptr_t addr;
2563 	txg_node_t *node;
2564 	int status;
2565 
2566 	while (wsp->walk_addr == NULL && lwd->lw_txgoff < lwd->lw_maxoff) {
2567 		lwd->lw_txgoff++;
2568 		wsp->walk_addr = lwd->lw_head[lwd->lw_txgoff];
2569 	}
2570 
2571 	if (wsp->walk_addr == NULL)
2572 		return (WALK_DONE);
2573 
2574 	addr = wsp->walk_addr - lwd->lw_offset;
2575 
2576 	if (mdb_vread(lwd->lw_obj,
2577 	    lwd->lw_offset + sizeof (txg_node_t), addr) == -1) {
2578 		mdb_warn("failed to read list element at %#lx", addr);
2579 		return (WALK_ERR);
2580 	}
2581 
2582 	status = wsp->walk_callback(addr, lwd->lw_obj, wsp->walk_cbdata);
2583 	node = (txg_node_t *)((uintptr_t)lwd->lw_obj + lwd->lw_offset);
2584 	wsp->walk_addr = (uintptr_t)node->tn_next[lwd->lw_txgoff];
2585 
2586 	return (status);
2587 }
2588 
2589 /*
2590  * ::walk spa
2591  *
2592  * Walk all named spa_t structures in the namespace.  This is nothing more than
2593  * a layered avl walk.
2594  */
2595 static int
2596 spa_walk_init(mdb_walk_state_t *wsp)
2597 {
2598 	GElf_Sym sym;
2599 
2600 	if (wsp->walk_addr != NULL) {
2601 		mdb_warn("spa walk only supports global walks\n");
2602 		return (WALK_ERR);
2603 	}
2604 
2605 	if (mdb_lookup_by_obj(ZFS_OBJ_NAME, "spa_namespace_avl", &sym) == -1) {
2606 		mdb_warn("failed to find symbol 'spa_namespace_avl'");
2607 		return (WALK_ERR);
2608 	}
2609 
2610 	wsp->walk_addr = (uintptr_t)sym.st_value;
2611 
2612 	if (mdb_layered_walk("avl", wsp) == -1) {
2613 		mdb_warn("failed to walk 'avl'\n");
2614 		return (WALK_ERR);
2615 	}
2616 
2617 	return (WALK_NEXT);
2618 }
2619 
2620 static int
2621 spa_walk_step(mdb_walk_state_t *wsp)
2622 {
2623 	return (wsp->walk_callback(wsp->walk_addr, NULL, wsp->walk_cbdata));
2624 }
2625 
2626 /*
2627  * [addr]::walk zio
2628  *
2629  * Walk all active zio_t structures on the system.  This is simply a layered
2630  * walk on top of ::walk zio_cache, with the optional ability to limit the
2631  * structures to a particular pool.
2632  */
2633 static int
2634 zio_walk_init(mdb_walk_state_t *wsp)
2635 {
2636 	wsp->walk_data = (void *)wsp->walk_addr;
2637 
2638 	if (mdb_layered_walk("zio_cache", wsp) == -1) {
2639 		mdb_warn("failed to walk 'zio_cache'\n");
2640 		return (WALK_ERR);
2641 	}
2642 
2643 	return (WALK_NEXT);
2644 }
2645 
2646 static int
2647 zio_walk_step(mdb_walk_state_t *wsp)
2648 {
2649 	mdb_zio_t zio;
2650 	uintptr_t spa = (uintptr_t)wsp->walk_data;
2651 
2652 	if (mdb_ctf_vread(&zio, ZFS_STRUCT "zio", "mdb_zio_t",
2653 	    wsp->walk_addr, 0) == -1)
2654 		return (WALK_ERR);
2655 
2656 	if (spa != 0 && spa != zio.io_spa)
2657 		return (WALK_NEXT);
2658 
2659 	return (wsp->walk_callback(wsp->walk_addr, &zio, wsp->walk_cbdata));
2660 }
2661 
2662 /*
2663  * [addr]::walk zio_root
2664  *
2665  * Walk only root zio_t structures, optionally for a particular spa_t.
2666  */
2667 static int
2668 zio_walk_root_step(mdb_walk_state_t *wsp)
2669 {
2670 	mdb_zio_t zio;
2671 	uintptr_t spa = (uintptr_t)wsp->walk_data;
2672 
2673 	if (mdb_ctf_vread(&zio, ZFS_STRUCT "zio", "mdb_zio_t",
2674 	    wsp->walk_addr, 0) == -1)
2675 		return (WALK_ERR);
2676 
2677 	if (spa != 0 && spa != zio.io_spa)
2678 		return (WALK_NEXT);
2679 
2680 	/* If the parent list is not empty, ignore */
2681 	if (zio.io_parent_list.list_head.list_next !=
2682 	    wsp->walk_addr +
2683 	    mdb_ctf_offsetof_by_name(ZFS_STRUCT "zio", "io_parent_list") +
2684 	    mdb_ctf_offsetof_by_name("struct list", "list_head"))
2685 		return (WALK_NEXT);
2686 
2687 	return (wsp->walk_callback(wsp->walk_addr, &zio, wsp->walk_cbdata));
2688 }
2689 
2690 /*
2691  * ::zfs_blkstats
2692  *
2693  *	-v	print verbose per-level information
2694  *
2695  */
2696 static int
2697 zfs_blkstats(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2698 {
2699 	boolean_t verbose = B_FALSE;
2700 	zfs_all_blkstats_t stats;
2701 	dmu_object_type_t t;
2702 	zfs_blkstat_t *tzb;
2703 	uint64_t ditto;
2704 	dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES + 10];
2705 	/* +10 in case it grew */
2706 
2707 	if (mdb_readvar(&dmu_ot, "dmu_ot") == -1) {
2708 		mdb_warn("failed to read 'dmu_ot'");
2709 		return (DCMD_ERR);
2710 	}
2711 
2712 	if (mdb_getopts(argc, argv,
2713 	    'v', MDB_OPT_SETBITS, TRUE, &verbose,
2714 	    NULL) != argc)
2715 		return (DCMD_USAGE);
2716 
2717 	if (!(flags & DCMD_ADDRSPEC))
2718 		return (DCMD_USAGE);
2719 
2720 	if (GETMEMB(addr, "spa", spa_dsl_pool, addr) ||
2721 	    GETMEMB(addr, "dsl_pool", dp_blkstats, addr) ||
2722 	    mdb_vread(&stats, sizeof (zfs_all_blkstats_t), addr) == -1) {
2723 		mdb_warn("failed to read data at %p;", addr);
2724 		mdb_printf("maybe no stats? run \"zpool scrub\" first.");
2725 		return (DCMD_ERR);
2726 	}
2727 
2728 	tzb = &stats.zab_type[DN_MAX_LEVELS][DMU_OT_TOTAL];
2729 	if (tzb->zb_gangs != 0) {
2730 		mdb_printf("Ganged blocks: %llu\n",
2731 		    (longlong_t)tzb->zb_gangs);
2732 	}
2733 
2734 	ditto = tzb->zb_ditto_2_of_2_samevdev + tzb->zb_ditto_2_of_3_samevdev +
2735 	    tzb->zb_ditto_3_of_3_samevdev;
2736 	if (ditto != 0) {
2737 		mdb_printf("Dittoed blocks on same vdev: %llu\n",
2738 		    (longlong_t)ditto);
2739 	}
2740 
2741 	mdb_printf("\nBlocks\tLSIZE\tPSIZE\tASIZE"
2742 	    "\t  avg\t comp\t%%Total\tType\n");
2743 
2744 	for (t = 0; t <= DMU_OT_TOTAL; t++) {
2745 		char csize[NICENUM_BUFLEN], lsize[NICENUM_BUFLEN];
2746 		char psize[NICENUM_BUFLEN], asize[NICENUM_BUFLEN];
2747 		char avg[NICENUM_BUFLEN];
2748 		char comp[NICENUM_BUFLEN], pct[NICENUM_BUFLEN];
2749 		char typename[64];
2750 		int l;
2751 
2752 
2753 		if (t == DMU_OT_DEFERRED)
2754 			strcpy(typename, "deferred free");
2755 		else if (t == DMU_OT_OTHER)
2756 			strcpy(typename, "other");
2757 		else if (t == DMU_OT_TOTAL)
2758 			strcpy(typename, "Total");
2759 		else if (mdb_readstr(typename, sizeof (typename),
2760 		    (uintptr_t)dmu_ot[t].ot_name) == -1) {
2761 			mdb_warn("failed to read type name");
2762 			return (DCMD_ERR);
2763 		}
2764 
2765 		if (stats.zab_type[DN_MAX_LEVELS][t].zb_asize == 0)
2766 			continue;
2767 
2768 		for (l = -1; l < DN_MAX_LEVELS; l++) {
2769 			int level = (l == -1 ? DN_MAX_LEVELS : l);
2770 			zfs_blkstat_t *zb = &stats.zab_type[level][t];
2771 
2772 			if (zb->zb_asize == 0)
2773 				continue;
2774 
2775 			/*
2776 			 * Don't print each level unless requested.
2777 			 */
2778 			if (!verbose && level != DN_MAX_LEVELS)
2779 				continue;
2780 
2781 			/*
2782 			 * If all the space is level 0, don't print the
2783 			 * level 0 separately.
2784 			 */
2785 			if (level == 0 && zb->zb_asize ==
2786 			    stats.zab_type[DN_MAX_LEVELS][t].zb_asize)
2787 				continue;
2788 
2789 			mdb_nicenum(zb->zb_count, csize);
2790 			mdb_nicenum(zb->zb_lsize, lsize);
2791 			mdb_nicenum(zb->zb_psize, psize);
2792 			mdb_nicenum(zb->zb_asize, asize);
2793 			mdb_nicenum(zb->zb_asize / zb->zb_count, avg);
2794 			(void) snprintfrac(comp, NICENUM_BUFLEN,
2795 			    zb->zb_lsize, zb->zb_psize, 2);
2796 			(void) snprintfrac(pct, NICENUM_BUFLEN,
2797 			    100 * zb->zb_asize, tzb->zb_asize, 2);
2798 
2799 			mdb_printf("%6s\t%5s\t%5s\t%5s\t%5s"
2800 			    "\t%5s\t%6s\t",
2801 			    csize, lsize, psize, asize, avg, comp, pct);
2802 
2803 			if (level == DN_MAX_LEVELS)
2804 				mdb_printf("%s\n", typename);
2805 			else
2806 				mdb_printf("  L%d %s\n",
2807 				    level, typename);
2808 		}
2809 	}
2810 
2811 	return (DCMD_OK);
2812 }
2813 
2814 typedef struct mdb_reference {
2815 	uintptr_t ref_holder;
2816 	uintptr_t ref_removed;
2817 	uint64_t ref_number;
2818 } mdb_reference_t;
2819 
2820 /* ARGSUSED */
2821 static int
2822 reference_cb(uintptr_t addr, const void *ignored, void *arg)
2823 {
2824 	mdb_reference_t ref;
2825 	boolean_t holder_is_str = B_FALSE;
2826 	char holder_str[128];
2827 	boolean_t removed = (boolean_t)arg;
2828 
2829 	if (mdb_ctf_vread(&ref, "reference_t", "mdb_reference_t", addr,
2830 	    0) == -1)
2831 		return (DCMD_ERR);
2832 
2833 	if (mdb_readstr(holder_str, sizeof (holder_str),
2834 	    ref.ref_holder) != -1)
2835 		holder_is_str = strisprint(holder_str);
2836 
2837 	if (removed)
2838 		mdb_printf("removed ");
2839 	mdb_printf("reference ");
2840 	if (ref.ref_number != 1)
2841 		mdb_printf("with count=%llu ", ref.ref_number);
2842 	mdb_printf("with tag %lx", ref.ref_holder);
2843 	if (holder_is_str)
2844 		mdb_printf(" \"%s\"", holder_str);
2845 	mdb_printf(", held at:\n");
2846 
2847 	(void) mdb_call_dcmd("whatis", addr, DCMD_ADDRSPEC, 0, NULL);
2848 
2849 	if (removed) {
2850 		mdb_printf("removed at:\n");
2851 		(void) mdb_call_dcmd("whatis", ref.ref_removed,
2852 		    DCMD_ADDRSPEC, 0, NULL);
2853 	}
2854 
2855 	mdb_printf("\n");
2856 
2857 	return (WALK_NEXT);
2858 }
2859 
2860 typedef struct mdb_refcount {
2861 	uint64_t rc_count;
2862 } mdb_refcount_t;
2863 
2864 typedef struct mdb_refcount_removed {
2865 	uint64_t rc_removed_count;
2866 } mdb_refcount_removed_t;
2867 
2868 typedef struct mdb_refcount_tracked {
2869 	boolean_t rc_tracked;
2870 } mdb_refcount_tracked_t;
2871 
2872 /* ARGSUSED */
2873 static int
2874 refcount(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2875 {
2876 	mdb_refcount_t rc;
2877 	mdb_refcount_removed_t rcr;
2878 	mdb_refcount_tracked_t rct;
2879 	int off;
2880 	boolean_t released = B_FALSE;
2881 
2882 	if (!(flags & DCMD_ADDRSPEC))
2883 		return (DCMD_USAGE);
2884 
2885 	if (mdb_getopts(argc, argv,
2886 	    'r', MDB_OPT_SETBITS, B_TRUE, &released,
2887 	    NULL) != argc)
2888 		return (DCMD_USAGE);
2889 
2890 	if (mdb_ctf_vread(&rc, "refcount_t", "mdb_refcount_t", addr,
2891 	    0) == -1)
2892 		return (DCMD_ERR);
2893 
2894 	if (mdb_ctf_vread(&rcr, "refcount_t", "mdb_refcount_removed_t", addr,
2895 	    MDB_CTF_VREAD_QUIET) == -1) {
2896 		mdb_printf("refcount_t at %p has %llu holds (untracked)\n",
2897 		    addr, (longlong_t)rc.rc_count);
2898 		return (DCMD_OK);
2899 	}
2900 
2901 	if (mdb_ctf_vread(&rct, "refcount_t", "mdb_refcount_tracked_t", addr,
2902 	    MDB_CTF_VREAD_QUIET) == -1) {
2903 		/* If this is an old target, it might be tracked. */
2904 		rct.rc_tracked = B_TRUE;
2905 	}
2906 
2907 	mdb_printf("refcount_t at %p has %llu current holds, "
2908 	    "%llu recently released holds\n",
2909 	    addr, (longlong_t)rc.rc_count, (longlong_t)rcr.rc_removed_count);
2910 
2911 	if (rct.rc_tracked && rc.rc_count > 0)
2912 		mdb_printf("current holds:\n");
2913 	off = mdb_ctf_offsetof_by_name("refcount_t", "rc_list");
2914 	if (off == -1)
2915 		return (DCMD_ERR);
2916 	mdb_pwalk("list", reference_cb, (void*)B_FALSE, addr + off);
2917 
2918 	if (released && rcr.rc_removed_count > 0) {
2919 		mdb_printf("released holds:\n");
2920 
2921 		off = mdb_ctf_offsetof_by_name("refcount_t", "rc_removed");
2922 		if (off == -1)
2923 			return (DCMD_ERR);
2924 		mdb_pwalk("list", reference_cb, (void*)B_TRUE, addr + off);
2925 	}
2926 
2927 	return (DCMD_OK);
2928 }
2929 
2930 /* ARGSUSED */
2931 static int
2932 sa_attr_table(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2933 {
2934 	sa_attr_table_t *table;
2935 	sa_os_t sa_os;
2936 	char *name;
2937 	int i;
2938 
2939 	if (mdb_vread(&sa_os, sizeof (sa_os_t), addr) == -1) {
2940 		mdb_warn("failed to read sa_os at %p", addr);
2941 		return (DCMD_ERR);
2942 	}
2943 
2944 	table = mdb_alloc(sizeof (sa_attr_table_t) * sa_os.sa_num_attrs,
2945 	    UM_SLEEP | UM_GC);
2946 	name = mdb_alloc(MAXPATHLEN, UM_SLEEP | UM_GC);
2947 
2948 	if (mdb_vread(table, sizeof (sa_attr_table_t) * sa_os.sa_num_attrs,
2949 	    (uintptr_t)sa_os.sa_attr_table) == -1) {
2950 		mdb_warn("failed to read sa_os at %p", addr);
2951 		return (DCMD_ERR);
2952 	}
2953 
2954 	mdb_printf("%<u>%-10s %-10s %-10s %-10s %s%</u>\n",
2955 	    "ATTR ID", "REGISTERED", "LENGTH", "BSWAP", "NAME");
2956 	for (i = 0; i != sa_os.sa_num_attrs; i++) {
2957 		mdb_readstr(name, MAXPATHLEN, (uintptr_t)table[i].sa_name);
2958 		mdb_printf("%5x   %8x %8x %8x          %-s\n",
2959 		    (int)table[i].sa_attr, (int)table[i].sa_registered,
2960 		    (int)table[i].sa_length, table[i].sa_byteswap, name);
2961 	}
2962 
2963 	return (DCMD_OK);
2964 }
2965 
2966 static int
2967 sa_get_off_table(uintptr_t addr, uint32_t **off_tab, int attr_count)
2968 {
2969 	uintptr_t idx_table;
2970 
2971 	if (GETMEMB(addr, "sa_idx_tab", sa_idx_tab, idx_table)) {
2972 		mdb_printf("can't find offset table in sa_idx_tab\n");
2973 		return (-1);
2974 	}
2975 
2976 	*off_tab = mdb_alloc(attr_count * sizeof (uint32_t),
2977 	    UM_SLEEP | UM_GC);
2978 
2979 	if (mdb_vread(*off_tab,
2980 	    attr_count * sizeof (uint32_t), idx_table) == -1) {
2981 		mdb_warn("failed to attribute offset table %p", idx_table);
2982 		return (-1);
2983 	}
2984 
2985 	return (DCMD_OK);
2986 }
2987 
2988 /*ARGSUSED*/
2989 static int
2990 sa_attr_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2991 {
2992 	uint32_t *offset_tab;
2993 	int attr_count;
2994 	uint64_t attr_id;
2995 	uintptr_t attr_addr;
2996 	uintptr_t bonus_tab, spill_tab;
2997 	uintptr_t db_bonus, db_spill;
2998 	uintptr_t os, os_sa;
2999 	uintptr_t db_data;
3000 
3001 	if (argc != 1)
3002 		return (DCMD_USAGE);
3003 
3004 	if (argv[0].a_type == MDB_TYPE_STRING)
3005 		attr_id = mdb_strtoull(argv[0].a_un.a_str);
3006 	else
3007 		return (DCMD_USAGE);
3008 
3009 	if (GETMEMB(addr, "sa_handle", sa_bonus_tab, bonus_tab) ||
3010 	    GETMEMB(addr, "sa_handle", sa_spill_tab, spill_tab) ||
3011 	    GETMEMB(addr, "sa_handle", sa_os, os) ||
3012 	    GETMEMB(addr, "sa_handle", sa_bonus, db_bonus) ||
3013 	    GETMEMB(addr, "sa_handle", sa_spill, db_spill)) {
3014 		mdb_printf("Can't find necessary information in sa_handle "
3015 		    "in sa_handle\n");
3016 		return (DCMD_ERR);
3017 	}
3018 
3019 	if (GETMEMB(os, "objset", os_sa, os_sa)) {
3020 		mdb_printf("Can't find os_sa in objset\n");
3021 		return (DCMD_ERR);
3022 	}
3023 
3024 	if (GETMEMB(os_sa, "sa_os", sa_num_attrs, attr_count)) {
3025 		mdb_printf("Can't find sa_num_attrs\n");
3026 		return (DCMD_ERR);
3027 	}
3028 
3029 	if (attr_id > attr_count) {
3030 		mdb_printf("attribute id number is out of range\n");
3031 		return (DCMD_ERR);
3032 	}
3033 
3034 	if (bonus_tab) {
3035 		if (sa_get_off_table(bonus_tab, &offset_tab,
3036 		    attr_count) == -1) {
3037 			return (DCMD_ERR);
3038 		}
3039 
3040 		if (GETMEMB(db_bonus, "dmu_buf", db_data, db_data)) {
3041 			mdb_printf("can't find db_data in bonus dbuf\n");
3042 			return (DCMD_ERR);
3043 		}
3044 	}
3045 
3046 	if (bonus_tab && !TOC_ATTR_PRESENT(offset_tab[attr_id]) &&
3047 	    spill_tab == NULL) {
3048 		mdb_printf("Attribute does not exist\n");
3049 		return (DCMD_ERR);
3050 	} else if (!TOC_ATTR_PRESENT(offset_tab[attr_id]) && spill_tab) {
3051 		if (sa_get_off_table(spill_tab, &offset_tab,
3052 		    attr_count) == -1) {
3053 			return (DCMD_ERR);
3054 		}
3055 		if (GETMEMB(db_spill, "dmu_buf", db_data, db_data)) {
3056 			mdb_printf("can't find db_data in spill dbuf\n");
3057 			return (DCMD_ERR);
3058 		}
3059 		if (!TOC_ATTR_PRESENT(offset_tab[attr_id])) {
3060 			mdb_printf("Attribute does not exist\n");
3061 			return (DCMD_ERR);
3062 		}
3063 	}
3064 	attr_addr = db_data + TOC_OFF(offset_tab[attr_id]);
3065 	mdb_printf("%p\n", attr_addr);
3066 	return (DCMD_OK);
3067 }
3068 
3069 /* ARGSUSED */
3070 static int
3071 zfs_ace_print_common(uintptr_t addr, uint_t flags,
3072     uint64_t id, uint32_t access_mask, uint16_t ace_flags,
3073     uint16_t ace_type, int verbose)
3074 {
3075 	if (DCMD_HDRSPEC(flags) && !verbose)
3076 		mdb_printf("%<u>%-?s %-8s %-8s %-8s %s%</u>\n",
3077 		    "ADDR", "FLAGS", "MASK", "TYPE", "ID");
3078 
3079 	if (!verbose) {
3080 		mdb_printf("%0?p %-8x %-8x %-8x %-llx\n", addr,
3081 		    ace_flags, access_mask, ace_type, id);
3082 		return (DCMD_OK);
3083 	}
3084 
3085 	switch (ace_flags & ACE_TYPE_FLAGS) {
3086 	case ACE_OWNER:
3087 		mdb_printf("owner@:");
3088 		break;
3089 	case (ACE_IDENTIFIER_GROUP | ACE_GROUP):
3090 		mdb_printf("group@:");
3091 		break;
3092 	case ACE_EVERYONE:
3093 		mdb_printf("everyone@:");
3094 		break;
3095 	case ACE_IDENTIFIER_GROUP:
3096 		mdb_printf("group:%llx:", (u_longlong_t)id);
3097 		break;
3098 	case 0: /* User entry */
3099 		mdb_printf("user:%llx:", (u_longlong_t)id);
3100 		break;
3101 	}
3102 
3103 	/* print out permission mask */
3104 	if (access_mask & ACE_READ_DATA)
3105 		mdb_printf("r");
3106 	else
3107 		mdb_printf("-");
3108 	if (access_mask & ACE_WRITE_DATA)
3109 		mdb_printf("w");
3110 	else
3111 		mdb_printf("-");
3112 	if (access_mask & ACE_EXECUTE)
3113 		mdb_printf("x");
3114 	else
3115 		mdb_printf("-");
3116 	if (access_mask & ACE_APPEND_DATA)
3117 		mdb_printf("p");
3118 	else
3119 		mdb_printf("-");
3120 	if (access_mask & ACE_DELETE)
3121 		mdb_printf("d");
3122 	else
3123 		mdb_printf("-");
3124 	if (access_mask & ACE_DELETE_CHILD)
3125 		mdb_printf("D");
3126 	else
3127 		mdb_printf("-");
3128 	if (access_mask & ACE_READ_ATTRIBUTES)
3129 		mdb_printf("a");
3130 	else
3131 		mdb_printf("-");
3132 	if (access_mask & ACE_WRITE_ATTRIBUTES)
3133 		mdb_printf("A");
3134 	else
3135 		mdb_printf("-");
3136 	if (access_mask & ACE_READ_NAMED_ATTRS)
3137 		mdb_printf("R");
3138 	else
3139 		mdb_printf("-");
3140 	if (access_mask & ACE_WRITE_NAMED_ATTRS)
3141 		mdb_printf("W");
3142 	else
3143 		mdb_printf("-");
3144 	if (access_mask & ACE_READ_ACL)
3145 		mdb_printf("c");
3146 	else
3147 		mdb_printf("-");
3148 	if (access_mask & ACE_WRITE_ACL)
3149 		mdb_printf("C");
3150 	else
3151 		mdb_printf("-");
3152 	if (access_mask & ACE_WRITE_OWNER)
3153 		mdb_printf("o");
3154 	else
3155 		mdb_printf("-");
3156 	if (access_mask & ACE_SYNCHRONIZE)
3157 		mdb_printf("s");
3158 	else
3159 		mdb_printf("-");
3160 
3161 	mdb_printf(":");
3162 
3163 	/* Print out inheritance flags */
3164 	if (ace_flags & ACE_FILE_INHERIT_ACE)
3165 		mdb_printf("f");
3166 	else
3167 		mdb_printf("-");
3168 	if (ace_flags & ACE_DIRECTORY_INHERIT_ACE)
3169 		mdb_printf("d");
3170 	else
3171 		mdb_printf("-");
3172 	if (ace_flags & ACE_INHERIT_ONLY_ACE)
3173 		mdb_printf("i");
3174 	else
3175 		mdb_printf("-");
3176 	if (ace_flags & ACE_NO_PROPAGATE_INHERIT_ACE)
3177 		mdb_printf("n");
3178 	else
3179 		mdb_printf("-");
3180 	if (ace_flags & ACE_SUCCESSFUL_ACCESS_ACE_FLAG)
3181 		mdb_printf("S");
3182 	else
3183 		mdb_printf("-");
3184 	if (ace_flags & ACE_FAILED_ACCESS_ACE_FLAG)
3185 		mdb_printf("F");
3186 	else
3187 		mdb_printf("-");
3188 	if (ace_flags & ACE_INHERITED_ACE)
3189 		mdb_printf("I");
3190 	else
3191 		mdb_printf("-");
3192 
3193 	switch (ace_type) {
3194 	case ACE_ACCESS_ALLOWED_ACE_TYPE:
3195 		mdb_printf(":allow\n");
3196 		break;
3197 	case ACE_ACCESS_DENIED_ACE_TYPE:
3198 		mdb_printf(":deny\n");
3199 		break;
3200 	case ACE_SYSTEM_AUDIT_ACE_TYPE:
3201 		mdb_printf(":audit\n");
3202 		break;
3203 	case ACE_SYSTEM_ALARM_ACE_TYPE:
3204 		mdb_printf(":alarm\n");
3205 		break;
3206 	default:
3207 		mdb_printf(":?\n");
3208 	}
3209 	return (DCMD_OK);
3210 }
3211 
3212 /* ARGSUSED */
3213 static int
3214 zfs_ace_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
3215 {
3216 	zfs_ace_t zace;
3217 	int verbose = FALSE;
3218 	uint64_t id;
3219 
3220 	if (!(flags & DCMD_ADDRSPEC))
3221 		return (DCMD_USAGE);
3222 
3223 	if (mdb_getopts(argc, argv,
3224 	    'v', MDB_OPT_SETBITS, TRUE, &verbose, TRUE, NULL) != argc)
3225 		return (DCMD_USAGE);
3226 
3227 	if (mdb_vread(&zace, sizeof (zfs_ace_t), addr) == -1) {
3228 		mdb_warn("failed to read zfs_ace_t");
3229 		return (DCMD_ERR);
3230 	}
3231 
3232 	if ((zace.z_hdr.z_flags & ACE_TYPE_FLAGS) == 0 ||
3233 	    (zace.z_hdr.z_flags & ACE_TYPE_FLAGS) == ACE_IDENTIFIER_GROUP)
3234 		id = zace.z_fuid;
3235 	else
3236 		id = -1;
3237 
3238 	return (zfs_ace_print_common(addr, flags, id, zace.z_hdr.z_access_mask,
3239 	    zace.z_hdr.z_flags, zace.z_hdr.z_type, verbose));
3240 }
3241 
3242 /* ARGSUSED */
3243 static int
3244 zfs_ace0_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
3245 {
3246 	ace_t ace;
3247 	uint64_t id;
3248 	int verbose = FALSE;
3249 
3250 	if (!(flags & DCMD_ADDRSPEC))
3251 		return (DCMD_USAGE);
3252 
3253 	if (mdb_getopts(argc, argv,
3254 	    'v', MDB_OPT_SETBITS, TRUE, &verbose, TRUE, NULL) != argc)
3255 		return (DCMD_USAGE);
3256 
3257 	if (mdb_vread(&ace, sizeof (ace_t), addr) == -1) {
3258 		mdb_warn("failed to read ace_t");
3259 		return (DCMD_ERR);
3260 	}
3261 
3262 	if ((ace.a_flags & ACE_TYPE_FLAGS) == 0 ||
3263 	    (ace.a_flags & ACE_TYPE_FLAGS) == ACE_IDENTIFIER_GROUP)
3264 		id = ace.a_who;
3265 	else
3266 		id = -1;
3267 
3268 	return (zfs_ace_print_common(addr, flags, id, ace.a_access_mask,
3269 	    ace.a_flags, ace.a_type, verbose));
3270 }
3271 
3272 typedef struct acl_dump_args {
3273 	int a_argc;
3274 	const mdb_arg_t *a_argv;
3275 	uint16_t a_version;
3276 	int a_flags;
3277 } acl_dump_args_t;
3278 
3279 /* ARGSUSED */
3280 static int
3281 acl_aces_cb(uintptr_t addr, const void *unknown, void *arg)
3282 {
3283 	acl_dump_args_t *acl_args = (acl_dump_args_t *)arg;
3284 
3285 	if (acl_args->a_version == 1) {
3286 		if (mdb_call_dcmd("zfs_ace", addr,
3287 		    DCMD_ADDRSPEC|acl_args->a_flags, acl_args->a_argc,
3288 		    acl_args->a_argv) != DCMD_OK) {
3289 			return (WALK_ERR);
3290 		}
3291 	} else {
3292 		if (mdb_call_dcmd("zfs_ace0", addr,
3293 		    DCMD_ADDRSPEC|acl_args->a_flags, acl_args->a_argc,
3294 		    acl_args->a_argv) != DCMD_OK) {
3295 			return (WALK_ERR);
3296 		}
3297 	}
3298 	acl_args->a_flags = DCMD_LOOP;
3299 	return (WALK_NEXT);
3300 }
3301 
3302 /* ARGSUSED */
3303 static int
3304 acl_cb(uintptr_t addr, const void *unknown, void *arg)
3305 {
3306 	acl_dump_args_t *acl_args = (acl_dump_args_t *)arg;
3307 
3308 	if (acl_args->a_version == 1) {
3309 		if (mdb_pwalk("zfs_acl_node_aces", acl_aces_cb,
3310 		    arg, addr) != 0) {
3311 			mdb_warn("can't walk ACEs");
3312 			return (DCMD_ERR);
3313 		}
3314 	} else {
3315 		if (mdb_pwalk("zfs_acl_node_aces0", acl_aces_cb,
3316 		    arg, addr) != 0) {
3317 			mdb_warn("can't walk ACEs");
3318 			return (DCMD_ERR);
3319 		}
3320 	}
3321 	return (WALK_NEXT);
3322 }
3323 
3324 /* ARGSUSED */
3325 static int
3326 zfs_acl_dump(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
3327 {
3328 	zfs_acl_t zacl;
3329 	int verbose = FALSE;
3330 	acl_dump_args_t acl_args;
3331 
3332 	if (!(flags & DCMD_ADDRSPEC))
3333 		return (DCMD_USAGE);
3334 
3335 	if (mdb_getopts(argc, argv,
3336 	    'v', MDB_OPT_SETBITS, TRUE, &verbose, TRUE, NULL) != argc)
3337 		return (DCMD_USAGE);
3338 
3339 	if (mdb_vread(&zacl, sizeof (zfs_acl_t), addr) == -1) {
3340 		mdb_warn("failed to read zfs_acl_t");
3341 		return (DCMD_ERR);
3342 	}
3343 
3344 	acl_args.a_argc = argc;
3345 	acl_args.a_argv = argv;
3346 	acl_args.a_version = zacl.z_version;
3347 	acl_args.a_flags = DCMD_LOOPFIRST;
3348 
3349 	if (mdb_pwalk("zfs_acl_node", acl_cb, &acl_args, addr) != 0) {
3350 		mdb_warn("can't walk ACL");
3351 		return (DCMD_ERR);
3352 	}
3353 
3354 	return (DCMD_OK);
3355 }
3356 
3357 /* ARGSUSED */
3358 static int
3359 zfs_acl_node_walk_init(mdb_walk_state_t *wsp)
3360 {
3361 	if (wsp->walk_addr == NULL) {
3362 		mdb_warn("must supply address of zfs_acl_node_t\n");
3363 		return (WALK_ERR);
3364 	}
3365 
3366 	wsp->walk_addr +=
3367 	    mdb_ctf_offsetof_by_name(ZFS_STRUCT "zfs_acl", "z_acl");
3368 
3369 	if (mdb_layered_walk("list", wsp) == -1) {
3370 		mdb_warn("failed to walk 'list'\n");
3371 		return (WALK_ERR);
3372 	}
3373 
3374 	return (WALK_NEXT);
3375 }
3376 
3377 static int
3378 zfs_acl_node_walk_step(mdb_walk_state_t *wsp)
3379 {
3380 	zfs_acl_node_t	aclnode;
3381 
3382 	if (mdb_vread(&aclnode, sizeof (zfs_acl_node_t),
3383 	    wsp->walk_addr) == -1) {
3384 		mdb_warn("failed to read zfs_acl_node at %p", wsp->walk_addr);
3385 		return (WALK_ERR);
3386 	}
3387 
3388 	return (wsp->walk_callback(wsp->walk_addr, &aclnode, wsp->walk_cbdata));
3389 }
3390 
3391 typedef struct ace_walk_data {
3392 	int		ace_count;
3393 	int		ace_version;
3394 } ace_walk_data_t;
3395 
3396 static int
3397 zfs_aces_walk_init_common(mdb_walk_state_t *wsp, int version,
3398     int ace_count, uintptr_t ace_data)
3399 {
3400 	ace_walk_data_t *ace_walk_data;
3401 
3402 	if (wsp->walk_addr == NULL) {
3403 		mdb_warn("must supply address of zfs_acl_node_t\n");
3404 		return (WALK_ERR);
3405 	}
3406 
3407 	ace_walk_data = mdb_alloc(sizeof (ace_walk_data_t), UM_SLEEP | UM_GC);
3408 
3409 	ace_walk_data->ace_count = ace_count;
3410 	ace_walk_data->ace_version = version;
3411 
3412 	wsp->walk_addr = ace_data;
3413 	wsp->walk_data = ace_walk_data;
3414 
3415 	return (WALK_NEXT);
3416 }
3417 
3418 static int
3419 zfs_acl_node_aces_walk_init_common(mdb_walk_state_t *wsp, int version)
3420 {
3421 	static int gotid;
3422 	static mdb_ctf_id_t acl_id;
3423 	int z_ace_count;
3424 	uintptr_t z_acldata;
3425 
3426 	if (!gotid) {
3427 		if (mdb_ctf_lookup_by_name("struct zfs_acl_node",
3428 		    &acl_id) == -1) {
3429 			mdb_warn("couldn't find struct zfs_acl_node");
3430 			return (DCMD_ERR);
3431 		}
3432 		gotid = TRUE;
3433 	}
3434 
3435 	if (GETMEMBID(wsp->walk_addr, &acl_id, z_ace_count, z_ace_count)) {
3436 		return (DCMD_ERR);
3437 	}
3438 	if (GETMEMBID(wsp->walk_addr, &acl_id, z_acldata, z_acldata)) {
3439 		return (DCMD_ERR);
3440 	}
3441 
3442 	return (zfs_aces_walk_init_common(wsp, version,
3443 	    z_ace_count, z_acldata));
3444 }
3445 
3446 /* ARGSUSED */
3447 static int
3448 zfs_acl_node_aces_walk_init(mdb_walk_state_t *wsp)
3449 {
3450 	return (zfs_acl_node_aces_walk_init_common(wsp, 1));
3451 }
3452 
3453 /* ARGSUSED */
3454 static int
3455 zfs_acl_node_aces0_walk_init(mdb_walk_state_t *wsp)
3456 {
3457 	return (zfs_acl_node_aces_walk_init_common(wsp, 0));
3458 }
3459 
3460 static int
3461 zfs_aces_walk_step(mdb_walk_state_t *wsp)
3462 {
3463 	ace_walk_data_t *ace_data = wsp->walk_data;
3464 	zfs_ace_t zace;
3465 	ace_t *acep;
3466 	int status;
3467 	int entry_type;
3468 	int allow_type;
3469 	uintptr_t ptr;
3470 
3471 	if (ace_data->ace_count == 0)
3472 		return (WALK_DONE);
3473 
3474 	if (mdb_vread(&zace, sizeof (zfs_ace_t), wsp->walk_addr) == -1) {
3475 		mdb_warn("failed to read zfs_ace_t at %#lx",
3476 		    wsp->walk_addr);
3477 		return (WALK_ERR);
3478 	}
3479 
3480 	switch (ace_data->ace_version) {
3481 	case 0:
3482 		acep = (ace_t *)&zace;
3483 		entry_type = acep->a_flags & ACE_TYPE_FLAGS;
3484 		allow_type = acep->a_type;
3485 		break;
3486 	case 1:
3487 		entry_type = zace.z_hdr.z_flags & ACE_TYPE_FLAGS;
3488 		allow_type = zace.z_hdr.z_type;
3489 		break;
3490 	default:
3491 		return (WALK_ERR);
3492 	}
3493 
3494 	ptr = (uintptr_t)wsp->walk_addr;
3495 	switch (entry_type) {
3496 	case ACE_OWNER:
3497 	case ACE_EVERYONE:
3498 	case (ACE_IDENTIFIER_GROUP | ACE_GROUP):
3499 		ptr += ace_data->ace_version == 0 ?
3500 		    sizeof (ace_t) : sizeof (zfs_ace_hdr_t);
3501 		break;
3502 	case ACE_IDENTIFIER_GROUP:
3503 	default:
3504 		switch (allow_type) {
3505 		case ACE_ACCESS_ALLOWED_OBJECT_ACE_TYPE:
3506 		case ACE_ACCESS_DENIED_OBJECT_ACE_TYPE:
3507 		case ACE_SYSTEM_AUDIT_OBJECT_ACE_TYPE:
3508 		case ACE_SYSTEM_ALARM_OBJECT_ACE_TYPE:
3509 			ptr += ace_data->ace_version == 0 ?
3510 			    sizeof (ace_t) : sizeof (zfs_object_ace_t);
3511 			break;
3512 		default:
3513 			ptr += ace_data->ace_version == 0 ?
3514 			    sizeof (ace_t) : sizeof (zfs_ace_t);
3515 			break;
3516 		}
3517 	}
3518 
3519 	ace_data->ace_count--;
3520 	status = wsp->walk_callback(wsp->walk_addr,
3521 	    (void *)(uintptr_t)&zace, wsp->walk_cbdata);
3522 
3523 	wsp->walk_addr = ptr;
3524 	return (status);
3525 }
3526 
3527 typedef struct mdb_zfs_rrwlock {
3528 	uintptr_t	rr_writer;
3529 	boolean_t	rr_writer_wanted;
3530 } mdb_zfs_rrwlock_t;
3531 
3532 static uint_t rrw_key;
3533 
3534 /* ARGSUSED */
3535 static int
3536 rrwlock(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
3537 {
3538 	mdb_zfs_rrwlock_t rrw;
3539 
3540 	if (rrw_key == 0) {
3541 		if (mdb_ctf_readsym(&rrw_key, "uint_t", "rrw_tsd_key", 0) == -1)
3542 			return (DCMD_ERR);
3543 	}
3544 
3545 	if (mdb_ctf_vread(&rrw, "rrwlock_t", "mdb_zfs_rrwlock_t", addr,
3546 	    0) == -1)
3547 		return (DCMD_ERR);
3548 
3549 	if (rrw.rr_writer != 0) {
3550 		mdb_printf("write lock held by thread %lx\n", rrw.rr_writer);
3551 		return (DCMD_OK);
3552 	}
3553 
3554 	if (rrw.rr_writer_wanted) {
3555 		mdb_printf("writer wanted\n");
3556 	}
3557 
3558 	mdb_printf("anonymous references:\n");
3559 	(void) mdb_call_dcmd("refcount", addr +
3560 	    mdb_ctf_offsetof_by_name(ZFS_STRUCT "rrwlock", "rr_anon_rcount"),
3561 	    DCMD_ADDRSPEC, 0, NULL);
3562 
3563 	mdb_printf("linked references:\n");
3564 	(void) mdb_call_dcmd("refcount", addr +
3565 	    mdb_ctf_offsetof_by_name(ZFS_STRUCT "rrwlock", "rr_linked_rcount"),
3566 	    DCMD_ADDRSPEC, 0, NULL);
3567 
3568 	/*
3569 	 * XXX This should find references from
3570 	 * "::walk thread | ::tsd -v <rrw_key>", but there is no support
3571 	 * for programmatic consumption of dcmds, so this would be
3572 	 * difficult, potentially requiring reimplementing ::tsd (both
3573 	 * user and kernel versions) in this MDB module.
3574 	 */
3575 
3576 	return (DCMD_OK);
3577 }
3578 
3579 typedef struct mdb_arc_buf_hdr_t {
3580 	uint16_t b_psize;
3581 	uint16_t b_lsize;
3582 	struct {
3583 		uint32_t	b_bufcnt;
3584 		uintptr_t	b_state;
3585 	} b_l1hdr;
3586 } mdb_arc_buf_hdr_t;
3587 
3588 enum arc_cflags {
3589 	ARC_CFLAG_VERBOSE		= 1 << 0,
3590 	ARC_CFLAG_ANON			= 1 << 1,
3591 	ARC_CFLAG_MRU			= 1 << 2,
3592 	ARC_CFLAG_MFU			= 1 << 3,
3593 	ARC_CFLAG_BUFS			= 1 << 4,
3594 };
3595 
3596 typedef struct arc_compression_stats_data {
3597 	GElf_Sym anon_sym;	/* ARC_anon symbol */
3598 	GElf_Sym mru_sym;	/* ARC_mru symbol */
3599 	GElf_Sym mrug_sym;	/* ARC_mru_ghost symbol */
3600 	GElf_Sym mfu_sym;	/* ARC_mfu symbol */
3601 	GElf_Sym mfug_sym;	/* ARC_mfu_ghost symbol */
3602 	GElf_Sym l2c_sym;	/* ARC_l2c_only symbol */
3603 	uint64_t *anon_c_hist;	/* histogram of compressed sizes in anon */
3604 	uint64_t *anon_u_hist;	/* histogram of uncompressed sizes in anon */
3605 	uint64_t *anon_bufs;	/* histogram of buffer counts in anon state */
3606 	uint64_t *mru_c_hist;	/* histogram of compressed sizes in mru */
3607 	uint64_t *mru_u_hist;	/* histogram of uncompressed sizes in mru */
3608 	uint64_t *mru_bufs;	/* histogram of buffer counts in mru */
3609 	uint64_t *mfu_c_hist;	/* histogram of compressed sizes in mfu */
3610 	uint64_t *mfu_u_hist;	/* histogram of uncompressed sizes in mfu */
3611 	uint64_t *mfu_bufs;	/* histogram of buffer counts in mfu */
3612 	uint64_t *all_c_hist;	/* histogram of compressed anon + mru + mfu */
3613 	uint64_t *all_u_hist;	/* histogram of uncompressed anon + mru + mfu */
3614 	uint64_t *all_bufs;	/* histogram of buffer counts in all states  */
3615 	int arc_cflags;		/* arc compression flags, specified by user */
3616 	int hist_nbuckets;	/* number of buckets in each histogram */
3617 } arc_compression_stats_data_t;
3618 
3619 int
3620 highbit64(uint64_t i)
3621 {
3622 	int h = 1;
3623 
3624 	if (i == 0)
3625 		return (0);
3626 	if (i & 0xffffffff00000000ULL) {
3627 		h += 32; i >>= 32;
3628 	}
3629 	if (i & 0xffff0000) {
3630 		h += 16; i >>= 16;
3631 	}
3632 	if (i & 0xff00) {
3633 		h += 8; i >>= 8;
3634 	}
3635 	if (i & 0xf0) {
3636 		h += 4; i >>= 4;
3637 	}
3638 	if (i & 0xc) {
3639 		h += 2; i >>= 2;
3640 	}
3641 	if (i & 0x2) {
3642 		h += 1;
3643 	}
3644 	return (h);
3645 }
3646 
3647 /* ARGSUSED */
3648 static int
3649 arc_compression_stats_cb(uintptr_t addr, const void *unknown, void *arg)
3650 {
3651 	arc_compression_stats_data_t *data = arg;
3652 	mdb_arc_buf_hdr_t hdr;
3653 	int cbucket, ubucket, bufcnt;
3654 
3655 	if (mdb_ctf_vread(&hdr, "arc_buf_hdr_t", "mdb_arc_buf_hdr_t",
3656 	    addr, 0) == -1) {
3657 		return (WALK_ERR);
3658 	}
3659 
3660 	/*
3661 	 * Headers in the ghost states, or the l2c_only state don't have
3662 	 * arc buffers linked off of them. Thus, their compressed size
3663 	 * is meaningless, so we skip these from the stats.
3664 	 */
3665 	if (hdr.b_l1hdr.b_state == data->mrug_sym.st_value ||
3666 	    hdr.b_l1hdr.b_state == data->mfug_sym.st_value ||
3667 	    hdr.b_l1hdr.b_state == data->l2c_sym.st_value) {
3668 		return (WALK_NEXT);
3669 	}
3670 
3671 	/*
3672 	 * The physical size (compressed) and logical size
3673 	 * (uncompressed) are in units of SPA_MINBLOCKSIZE. By default,
3674 	 * we use the log2 of this value (rounded down to the nearest
3675 	 * integer) to determine the bucket to assign this header to.
3676 	 * Thus, the histogram is logarithmic with respect to the size
3677 	 * of the header. For example, the following is a mapping of the
3678 	 * bucket numbers and the range of header sizes they correspond to:
3679 	 *
3680 	 *	0: 0 byte headers
3681 	 *	1: 512 byte headers
3682 	 *	2: [1024 - 2048) byte headers
3683 	 *	3: [2048 - 4096) byte headers
3684 	 *	4: [4096 - 8192) byte headers
3685 	 *	5: [8192 - 16394) byte headers
3686 	 *	6: [16384 - 32768) byte headers
3687 	 *	7: [32768 - 65536) byte headers
3688 	 *	8: [65536 - 131072) byte headers
3689 	 *	9: 131072 byte headers
3690 	 *
3691 	 * If the ARC_CFLAG_VERBOSE flag was specified, we use the
3692 	 * physical and logical sizes directly. Thus, the histogram will
3693 	 * no longer be logarithmic; instead it will be linear with
3694 	 * respect to the size of the header. The following is a mapping
3695 	 * of the first many bucket numbers and the header size they
3696 	 * correspond to:
3697 	 *
3698 	 *	0: 0 byte headers
3699 	 *	1: 512 byte headers
3700 	 *	2: 1024 byte headers
3701 	 *	3: 1536 byte headers
3702 	 *	4: 2048 byte headers
3703 	 *	5: 2560 byte headers
3704 	 *	6: 3072 byte headers
3705 	 *
3706 	 * And so on. Keep in mind that a range of sizes isn't used in
3707 	 * the case of linear scale because the headers can only
3708 	 * increment or decrement in sizes of 512 bytes. So, it's not
3709 	 * possible for a header to be sized in between whats listed
3710 	 * above.
3711 	 *
3712 	 * Also, the above mapping values were calculated assuming a
3713 	 * SPA_MINBLOCKSHIFT of 512 bytes and a SPA_MAXBLOCKSIZE of 128K.
3714 	 */
3715 
3716 	if (data->arc_cflags & ARC_CFLAG_VERBOSE) {
3717 		cbucket = hdr.b_psize;
3718 		ubucket = hdr.b_lsize;
3719 	} else {
3720 		cbucket = highbit64(hdr.b_psize);
3721 		ubucket = highbit64(hdr.b_lsize);
3722 	}
3723 
3724 	bufcnt = hdr.b_l1hdr.b_bufcnt;
3725 	if (bufcnt >= data->hist_nbuckets)
3726 		bufcnt = data->hist_nbuckets - 1;
3727 
3728 	/* Ensure we stay within the bounds of the histogram array */
3729 	ASSERT3U(cbucket, <, data->hist_nbuckets);
3730 	ASSERT3U(ubucket, <, data->hist_nbuckets);
3731 
3732 	if (hdr.b_l1hdr.b_state == data->anon_sym.st_value) {
3733 		data->anon_c_hist[cbucket]++;
3734 		data->anon_u_hist[ubucket]++;
3735 		data->anon_bufs[bufcnt]++;
3736 	} else if (hdr.b_l1hdr.b_state == data->mru_sym.st_value) {
3737 		data->mru_c_hist[cbucket]++;
3738 		data->mru_u_hist[ubucket]++;
3739 		data->mru_bufs[bufcnt]++;
3740 	} else if (hdr.b_l1hdr.b_state == data->mfu_sym.st_value) {
3741 		data->mfu_c_hist[cbucket]++;
3742 		data->mfu_u_hist[ubucket]++;
3743 		data->mfu_bufs[bufcnt]++;
3744 	}
3745 
3746 	data->all_c_hist[cbucket]++;
3747 	data->all_u_hist[ubucket]++;
3748 	data->all_bufs[bufcnt]++;
3749 
3750 	return (WALK_NEXT);
3751 }
3752 
3753 /* ARGSUSED */
3754 static int
3755 arc_compression_stats(uintptr_t addr, uint_t flags, int argc,
3756     const mdb_arg_t *argv)
3757 {
3758 	arc_compression_stats_data_t data = { 0 };
3759 	unsigned int max_shifted = SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT;
3760 	unsigned int hist_size;
3761 	char range[32];
3762 	int rc = DCMD_OK;
3763 
3764 	if (mdb_getopts(argc, argv,
3765 	    'v', MDB_OPT_SETBITS, ARC_CFLAG_VERBOSE, &data.arc_cflags,
3766 	    'a', MDB_OPT_SETBITS, ARC_CFLAG_ANON, &data.arc_cflags,
3767 	    'b', MDB_OPT_SETBITS, ARC_CFLAG_BUFS, &data.arc_cflags,
3768 	    'r', MDB_OPT_SETBITS, ARC_CFLAG_MRU, &data.arc_cflags,
3769 	    'f', MDB_OPT_SETBITS, ARC_CFLAG_MFU, &data.arc_cflags) != argc)
3770 		return (DCMD_USAGE);
3771 
3772 	if (mdb_lookup_by_obj(ZFS_OBJ_NAME, "ARC_anon", &data.anon_sym) ||
3773 	    mdb_lookup_by_obj(ZFS_OBJ_NAME, "ARC_mru", &data.mru_sym) ||
3774 	    mdb_lookup_by_obj(ZFS_OBJ_NAME, "ARC_mru_ghost", &data.mrug_sym) ||
3775 	    mdb_lookup_by_obj(ZFS_OBJ_NAME, "ARC_mfu", &data.mfu_sym) ||
3776 	    mdb_lookup_by_obj(ZFS_OBJ_NAME, "ARC_mfu_ghost", &data.mfug_sym) ||
3777 	    mdb_lookup_by_obj(ZFS_OBJ_NAME, "ARC_l2c_only", &data.l2c_sym)) {
3778 		mdb_warn("can't find arc state symbol");
3779 		return (DCMD_ERR);
3780 	}
3781 
3782 	/*
3783 	 * Determine the maximum expected size for any header, and use
3784 	 * this to determine the number of buckets needed for each
3785 	 * histogram. If ARC_CFLAG_VERBOSE is specified, this value is
3786 	 * used directly; otherwise the log2 of the maximum size is
3787 	 * used. Thus, if using a log2 scale there's a maximum of 10
3788 	 * possible buckets, while the linear scale (when using
3789 	 * ARC_CFLAG_VERBOSE) has a maximum of 257 buckets.
3790 	 */
3791 	if (data.arc_cflags & ARC_CFLAG_VERBOSE)
3792 		data.hist_nbuckets = max_shifted + 1;
3793 	else
3794 		data.hist_nbuckets = highbit64(max_shifted) + 1;
3795 
3796 	hist_size = sizeof (uint64_t) * data.hist_nbuckets;
3797 
3798 	data.anon_c_hist = mdb_zalloc(hist_size, UM_SLEEP);
3799 	data.anon_u_hist = mdb_zalloc(hist_size, UM_SLEEP);
3800 	data.anon_bufs = mdb_zalloc(hist_size, UM_SLEEP);
3801 
3802 	data.mru_c_hist = mdb_zalloc(hist_size, UM_SLEEP);
3803 	data.mru_u_hist = mdb_zalloc(hist_size, UM_SLEEP);
3804 	data.mru_bufs = mdb_zalloc(hist_size, UM_SLEEP);
3805 
3806 	data.mfu_c_hist = mdb_zalloc(hist_size, UM_SLEEP);
3807 	data.mfu_u_hist = mdb_zalloc(hist_size, UM_SLEEP);
3808 	data.mfu_bufs = mdb_zalloc(hist_size, UM_SLEEP);
3809 
3810 	data.all_c_hist = mdb_zalloc(hist_size, UM_SLEEP);
3811 	data.all_u_hist = mdb_zalloc(hist_size, UM_SLEEP);
3812 	data.all_bufs = mdb_zalloc(hist_size, UM_SLEEP);
3813 
3814 	if (mdb_walk("arc_buf_hdr_t_full", arc_compression_stats_cb,
3815 	    &data) != 0) {
3816 		mdb_warn("can't walk arc_buf_hdr's");
3817 		rc = DCMD_ERR;
3818 		goto out;
3819 	}
3820 
3821 	if (data.arc_cflags & ARC_CFLAG_VERBOSE) {
3822 		rc = mdb_snprintf(range, sizeof (range),
3823 		    "[n*%llu, (n+1)*%llu)", SPA_MINBLOCKSIZE,
3824 		    SPA_MINBLOCKSIZE);
3825 	} else {
3826 		rc = mdb_snprintf(range, sizeof (range),
3827 		    "[2^(n-1)*%llu, 2^n*%llu)", SPA_MINBLOCKSIZE,
3828 		    SPA_MINBLOCKSIZE);
3829 	}
3830 
3831 	if (rc < 0) {
3832 		/* snprintf failed, abort the dcmd */
3833 		rc = DCMD_ERR;
3834 		goto out;
3835 	} else {
3836 		/* snprintf succeeded above, reset return code */
3837 		rc = DCMD_OK;
3838 	}
3839 
3840 	if (data.arc_cflags & ARC_CFLAG_ANON) {
3841 		if (data.arc_cflags & ARC_CFLAG_BUFS) {
3842 			mdb_printf("Histogram of the number of anon buffers "
3843 			    "that are associated with an arc hdr.\n");
3844 			dump_histogram(data.anon_bufs, data.hist_nbuckets, 0);
3845 			mdb_printf("\n");
3846 		}
3847 		mdb_printf("Histogram of compressed anon buffers.\n"
3848 		    "Each bucket represents buffers of size: %s.\n", range);
3849 		dump_histogram(data.anon_c_hist, data.hist_nbuckets, 0);
3850 		mdb_printf("\n");
3851 
3852 		mdb_printf("Histogram of uncompressed anon buffers.\n"
3853 		    "Each bucket represents buffers of size: %s.\n", range);
3854 		dump_histogram(data.anon_u_hist, data.hist_nbuckets, 0);
3855 		mdb_printf("\n");
3856 	}
3857 
3858 	if (data.arc_cflags & ARC_CFLAG_MRU) {
3859 		if (data.arc_cflags & ARC_CFLAG_BUFS) {
3860 			mdb_printf("Histogram of the number of mru buffers "
3861 			    "that are associated with an arc hdr.\n");
3862 			dump_histogram(data.mru_bufs, data.hist_nbuckets, 0);
3863 			mdb_printf("\n");
3864 		}
3865 		mdb_printf("Histogram of compressed mru buffers.\n"
3866 		    "Each bucket represents buffers of size: %s.\n", range);
3867 		dump_histogram(data.mru_c_hist, data.hist_nbuckets, 0);
3868 		mdb_printf("\n");
3869 
3870 		mdb_printf("Histogram of uncompressed mru buffers.\n"
3871 		    "Each bucket represents buffers of size: %s.\n", range);
3872 		dump_histogram(data.mru_u_hist, data.hist_nbuckets, 0);
3873 		mdb_printf("\n");
3874 	}
3875 
3876 	if (data.arc_cflags & ARC_CFLAG_MFU) {
3877 		if (data.arc_cflags & ARC_CFLAG_BUFS) {
3878 			mdb_printf("Histogram of the number of mfu buffers "
3879 			    "that are associated with an arc hdr.\n");
3880 			dump_histogram(data.mfu_bufs, data.hist_nbuckets, 0);
3881 			mdb_printf("\n");
3882 		}
3883 
3884 		mdb_printf("Histogram of compressed mfu buffers.\n"
3885 		    "Each bucket represents buffers of size: %s.\n", range);
3886 		dump_histogram(data.mfu_c_hist, data.hist_nbuckets, 0);
3887 		mdb_printf("\n");
3888 
3889 		mdb_printf("Histogram of uncompressed mfu buffers.\n"
3890 		    "Each bucket represents buffers of size: %s.\n", range);
3891 		dump_histogram(data.mfu_u_hist, data.hist_nbuckets, 0);
3892 		mdb_printf("\n");
3893 	}
3894 
3895 	if (data.arc_cflags & ARC_CFLAG_BUFS) {
3896 		mdb_printf("Histogram of all buffers that "
3897 		    "are associated with an arc hdr.\n");
3898 		dump_histogram(data.all_bufs, data.hist_nbuckets, 0);
3899 		mdb_printf("\n");
3900 	}
3901 
3902 	mdb_printf("Histogram of all compressed buffers.\n"
3903 	    "Each bucket represents buffers of size: %s.\n", range);
3904 	dump_histogram(data.all_c_hist, data.hist_nbuckets, 0);
3905 	mdb_printf("\n");
3906 
3907 	mdb_printf("Histogram of all uncompressed buffers.\n"
3908 	    "Each bucket represents buffers of size: %s.\n", range);
3909 	dump_histogram(data.all_u_hist, data.hist_nbuckets, 0);
3910 
3911 out:
3912 	mdb_free(data.anon_c_hist, hist_size);
3913 	mdb_free(data.anon_u_hist, hist_size);
3914 	mdb_free(data.anon_bufs, hist_size);
3915 
3916 	mdb_free(data.mru_c_hist, hist_size);
3917 	mdb_free(data.mru_u_hist, hist_size);
3918 	mdb_free(data.mru_bufs, hist_size);
3919 
3920 	mdb_free(data.mfu_c_hist, hist_size);
3921 	mdb_free(data.mfu_u_hist, hist_size);
3922 	mdb_free(data.mfu_bufs, hist_size);
3923 
3924 	mdb_free(data.all_c_hist, hist_size);
3925 	mdb_free(data.all_u_hist, hist_size);
3926 	mdb_free(data.all_bufs, hist_size);
3927 
3928 	return (rc);
3929 }
3930 
3931 /*
3932  * MDB module linkage information:
3933  *
3934  * We declare a list of structures describing our dcmds, and a function
3935  * named _mdb_init to return a pointer to our module information.
3936  */
3937 
3938 static const mdb_dcmd_t dcmds[] = {
3939 	{ "arc", "[-bkmg]", "print ARC variables", arc_print },
3940 	{ "blkptr", ":", "print blkptr_t", blkptr },
3941 	{ "dva", ":", "print dva_t", dva },
3942 	{ "dbuf", ":", "print dmu_buf_impl_t", dbuf },
3943 	{ "dbuf_stats", ":", "dbuf stats", dbuf_stats },
3944 	{ "dbufs",
3945 	    "\t[-O objset_t*] [-n objset_name | \"mos\"] "
3946 	    "[-o object | \"mdn\"] \n"
3947 	    "\t[-l level] [-b blkid | \"bonus\"]",
3948 	    "find dmu_buf_impl_t's that match specified criteria", dbufs },
3949 	{ "abuf_find", "dva_word[0] dva_word[1]",
3950 	    "find arc_buf_hdr_t of a specified DVA",
3951 	    abuf_find },
3952 	{ "spa", "?[-cevmMh]\n"
3953 	    "\t-c display spa config\n"
3954 	    "\t-e display vdev statistics\n"
3955 	    "\t-v display vdev information\n"
3956 	    "\t-m display metaslab statistics\n"
3957 	    "\t-M display metaslab group statistics\n"
3958 	    "\t-h display histogram (requires -m or -M)\n",
3959 	    "spa_t summary", spa_print },
3960 	{ "spa_config", ":", "print spa_t configuration", spa_print_config },
3961 	{ "spa_space", ":[-b]", "print spa_t on-disk space usage", spa_space },
3962 	{ "spa_vdevs", ":[-emMh]\n"
3963 	    "\t-e display vdev statistics\n"
3964 	    "\t-m dispaly metaslab statistics\n"
3965 	    "\t-M display metaslab group statistic\n"
3966 	    "\t-h display histogram (requires -m or -M)\n",
3967 	    "given a spa_t, print vdev summary", spa_vdevs },
3968 	{ "vdev", ":[-remMh]\n"
3969 	    "\t-r display recursively\n"
3970 	    "\t-e display statistics\n"
3971 	    "\t-m display metaslab statistics (top level vdev only)\n"
3972 	    "\t-M display metaslab group statistics (top level vdev only)\n"
3973 	    "\t-h display histogram (requires -m or -M)\n",
3974 	    "vdev_t summary", vdev_print },
3975 	{ "zio", ":[-cpr]\n"
3976 	    "\t-c display children\n"
3977 	    "\t-p display parents\n"
3978 	    "\t-r display recursively",
3979 	    "zio_t summary", zio_print },
3980 	{ "zio_state", "?", "print out all zio_t structures on system or "
3981 	    "for a particular pool", zio_state },
3982 	{ "zfs_blkstats", ":[-v]",
3983 	    "given a spa_t, print block type stats from last scrub",
3984 	    zfs_blkstats },
3985 	{ "zfs_params", "", "print zfs tunable parameters", zfs_params },
3986 	{ "refcount", ":[-r]\n"
3987 	    "\t-r display recently removed references",
3988 	    "print refcount_t holders", refcount },
3989 	{ "zap_leaf", "", "print zap_leaf_phys_t", zap_leaf },
3990 	{ "zfs_aces", ":[-v]", "print all ACEs from a zfs_acl_t",
3991 	    zfs_acl_dump },
3992 	{ "zfs_ace", ":[-v]", "print zfs_ace", zfs_ace_print },
3993 	{ "zfs_ace0", ":[-v]", "print zfs_ace0", zfs_ace0_print },
3994 	{ "sa_attr_table", ":", "print SA attribute table from sa_os_t",
3995 	    sa_attr_table},
3996 	{ "sa_attr", ": attr_id",
3997 	    "print SA attribute address when given sa_handle_t", sa_attr_print},
3998 	{ "zfs_dbgmsg", ":[-va]",
3999 	    "print zfs debug log", dbgmsg},
4000 	{ "rrwlock", ":",
4001 	    "print rrwlock_t, including readers", rrwlock},
4002 	{ "metaslab_weight", "weight",
4003 	    "print metaslab weight", metaslab_weight},
4004 	{ "metaslab_trace", ":",
4005 	    "print metaslab allocation trace records", metaslab_trace},
4006 	{ "arc_compression_stats", ":[-vabrf]\n"
4007 	    "\t-v verbose, display a linearly scaled histogram\n"
4008 	    "\t-a display ARC_anon state statistics individually\n"
4009 	    "\t-r display ARC_mru state statistics individually\n"
4010 	    "\t-f display ARC_mfu state statistics individually\n"
4011 	    "\t-b display histogram of buffer counts\n",
4012 	    "print a histogram of compressed arc buffer sizes",
4013 	    arc_compression_stats},
4014 	{ NULL }
4015 };
4016 
4017 static const mdb_walker_t walkers[] = {
4018 	{ "zms_freelist", "walk ZFS metaslab freelist",
4019 	    freelist_walk_init, freelist_walk_step, NULL },
4020 	{ "txg_list", "given any txg_list_t *, walk all entries in all txgs",
4021 	    txg_list_walk_init, txg_list_walk_step, NULL },
4022 	{ "txg_list0", "given any txg_list_t *, walk all entries in txg 0",
4023 	    txg_list0_walk_init, txg_list_walk_step, NULL },
4024 	{ "txg_list1", "given any txg_list_t *, walk all entries in txg 1",
4025 	    txg_list1_walk_init, txg_list_walk_step, NULL },
4026 	{ "txg_list2", "given any txg_list_t *, walk all entries in txg 2",
4027 	    txg_list2_walk_init, txg_list_walk_step, NULL },
4028 	{ "txg_list3", "given any txg_list_t *, walk all entries in txg 3",
4029 	    txg_list3_walk_init, txg_list_walk_step, NULL },
4030 	{ "zio", "walk all zio structures, optionally for a particular spa_t",
4031 	    zio_walk_init, zio_walk_step, NULL },
4032 	{ "zio_root",
4033 	    "walk all root zio_t structures, optionally for a particular spa_t",
4034 	    zio_walk_init, zio_walk_root_step, NULL },
4035 	{ "spa", "walk all spa_t entries in the namespace",
4036 	    spa_walk_init, spa_walk_step, NULL },
4037 	{ "metaslab", "given a spa_t *, walk all metaslab_t structures",
4038 	    metaslab_walk_init, metaslab_walk_step, NULL },
4039 	{ "multilist", "given a multilist_t *, walk all list_t structures",
4040 	    multilist_walk_init, multilist_walk_step, NULL },
4041 	{ "zfs_acl_node", "given a zfs_acl_t, walk all zfs_acl_nodes",
4042 	    zfs_acl_node_walk_init, zfs_acl_node_walk_step, NULL },
4043 	{ "zfs_acl_node_aces", "given a zfs_acl_node_t, walk all ACEs",
4044 	    zfs_acl_node_aces_walk_init, zfs_aces_walk_step, NULL },
4045 	{ "zfs_acl_node_aces0",
4046 	    "given a zfs_acl_node_t, walk all ACEs as ace_t",
4047 	    zfs_acl_node_aces0_walk_init, zfs_aces_walk_step, NULL },
4048 	{ NULL }
4049 };
4050 
4051 static const mdb_modinfo_t modinfo = {
4052 	MDB_API_VERSION, dcmds, walkers
4053 };
4054 
4055 const mdb_modinfo_t *
4056 _mdb_init(void)
4057 {
4058 	return (&modinfo);
4059 }
4060