xref: /illumos-gate/usr/src/cmd/mdb/common/modules/zfs/zfs.c (revision ebe61a78)
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, 2018 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 /*
135  * <addr>::sm_entries <buffer length in bytes>
136  *
137  * Treat the buffer specified by the given address as a buffer that contains
138  * space map entries. Iterate over the specified number of entries and print
139  * them in both encoded and decoded form.
140  */
141 /* ARGSUSED */
142 static int
143 sm_entries(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
144 {
145 	uint64_t bufsz = 0;
146 	boolean_t preview = B_FALSE;
147 
148 	if (!(flags & DCMD_ADDRSPEC))
149 		return (DCMD_USAGE);
150 
151 	if (argc < 1) {
152 		preview = B_TRUE;
153 		bufsz = 2;
154 	} else if (argc != 1) {
155 		return (DCMD_USAGE);
156 	} else {
157 		switch (argv[0].a_type) {
158 		case MDB_TYPE_STRING:
159 			bufsz = mdb_strtoull(argv[0].a_un.a_str);
160 			break;
161 		case MDB_TYPE_IMMEDIATE:
162 			bufsz = argv[0].a_un.a_val;
163 			break;
164 		default:
165 			return (DCMD_USAGE);
166 		}
167 	}
168 
169 	char *actions[] = { "ALLOC", "FREE", "INVALID" };
170 	for (uintptr_t bufend = addr + bufsz; addr < bufend;
171 	    addr += sizeof (uint64_t)) {
172 		uint64_t nwords;
173 		uint64_t start_addr = addr;
174 
175 		uint64_t word = 0;
176 		if (mdb_vread(&word, sizeof (word), addr) == -1) {
177 			mdb_warn("failed to read space map entry %p", addr);
178 			return (DCMD_ERR);
179 		}
180 
181 		if (SM_PREFIX_DECODE(word) == SM_DEBUG_PREFIX) {
182 			(void) mdb_printf("\t    [%6llu] %s: txg %llu, "
183 			    "pass %llu\n",
184 			    (u_longlong_t)(addr),
185 			    actions[SM_DEBUG_ACTION_DECODE(word)],
186 			    (u_longlong_t)SM_DEBUG_TXG_DECODE(word),
187 			    (u_longlong_t)SM_DEBUG_SYNCPASS_DECODE(word));
188 			continue;
189 		}
190 
191 		char entry_type;
192 		uint64_t raw_offset, raw_run, vdev_id = SM_NO_VDEVID;
193 
194 		if (SM_PREFIX_DECODE(word) != SM2_PREFIX) {
195 			entry_type = (SM_TYPE_DECODE(word) == SM_ALLOC) ?
196 			    'A' : 'F';
197 			raw_offset = SM_OFFSET_DECODE(word);
198 			raw_run = SM_RUN_DECODE(word);
199 			nwords = 1;
200 		} else {
201 			ASSERT3U(SM_PREFIX_DECODE(word), ==, SM2_PREFIX);
202 
203 			raw_run = SM2_RUN_DECODE(word);
204 			vdev_id = SM2_VDEV_DECODE(word);
205 
206 			/* it is a two-word entry so we read another word */
207 			addr += sizeof (uint64_t);
208 			if (addr >= bufend) {
209 				mdb_warn("buffer ends in the middle of a two "
210 				    "word entry\n", addr);
211 				return (DCMD_ERR);
212 			}
213 
214 			if (mdb_vread(&word, sizeof (word), addr) == -1) {
215 				mdb_warn("failed to read space map entry %p",
216 				    addr);
217 				return (DCMD_ERR);
218 			}
219 
220 			entry_type = (SM2_TYPE_DECODE(word) == SM_ALLOC) ?
221 			    'A' : 'F';
222 			raw_offset = SM2_OFFSET_DECODE(word);
223 			nwords = 2;
224 		}
225 
226 		(void) mdb_printf("\t    [%6llx]    %c  range:"
227 		    " %010llx-%010llx  size: %06llx vdev: %06llu words: %llu\n",
228 		    (u_longlong_t)start_addr,
229 		    entry_type, (u_longlong_t)raw_offset,
230 		    (u_longlong_t)(raw_offset + raw_run),
231 		    (u_longlong_t)raw_run,
232 		    (u_longlong_t)vdev_id, (u_longlong_t)nwords);
233 
234 		if (preview)
235 			break;
236 	}
237 	return (DCMD_OK);
238 }
239 
240 static int
241 mdb_dsl_dir_name(uintptr_t addr, char *buf)
242 {
243 	static int gotid;
244 	static mdb_ctf_id_t dd_id;
245 	uintptr_t dd_parent;
246 	char dd_myname[ZFS_MAX_DATASET_NAME_LEN];
247 
248 	if (!gotid) {
249 		if (mdb_ctf_lookup_by_name(ZFS_STRUCT "dsl_dir",
250 		    &dd_id) == -1) {
251 			mdb_warn("couldn't find struct dsl_dir");
252 			return (DCMD_ERR);
253 		}
254 		gotid = TRUE;
255 	}
256 	if (GETMEMBID(addr, &dd_id, dd_parent, dd_parent) ||
257 	    GETMEMBID(addr, &dd_id, dd_myname, dd_myname)) {
258 		return (DCMD_ERR);
259 	}
260 
261 	if (dd_parent) {
262 		if (mdb_dsl_dir_name(dd_parent, buf))
263 			return (DCMD_ERR);
264 		strcat(buf, "/");
265 	}
266 
267 	if (dd_myname[0])
268 		strcat(buf, dd_myname);
269 	else
270 		strcat(buf, "???");
271 
272 	return (0);
273 }
274 
275 static int
276 objset_name(uintptr_t addr, char *buf)
277 {
278 	static int gotid;
279 	static mdb_ctf_id_t os_id, ds_id;
280 	uintptr_t os_dsl_dataset;
281 	char ds_snapname[ZFS_MAX_DATASET_NAME_LEN];
282 	uintptr_t ds_dir;
283 
284 	buf[0] = '\0';
285 
286 	if (!gotid) {
287 		if (mdb_ctf_lookup_by_name(ZFS_STRUCT "objset",
288 		    &os_id) == -1) {
289 			mdb_warn("couldn't find struct objset");
290 			return (DCMD_ERR);
291 		}
292 		if (mdb_ctf_lookup_by_name(ZFS_STRUCT "dsl_dataset",
293 		    &ds_id) == -1) {
294 			mdb_warn("couldn't find struct dsl_dataset");
295 			return (DCMD_ERR);
296 		}
297 
298 		gotid = TRUE;
299 	}
300 
301 	if (GETMEMBID(addr, &os_id, os_dsl_dataset, os_dsl_dataset))
302 		return (DCMD_ERR);
303 
304 	if (os_dsl_dataset == 0) {
305 		strcat(buf, "mos");
306 		return (0);
307 	}
308 
309 	if (GETMEMBID(os_dsl_dataset, &ds_id, ds_snapname, ds_snapname) ||
310 	    GETMEMBID(os_dsl_dataset, &ds_id, ds_dir, ds_dir)) {
311 		return (DCMD_ERR);
312 	}
313 
314 	if (ds_dir && mdb_dsl_dir_name(ds_dir, buf))
315 		return (DCMD_ERR);
316 
317 	if (ds_snapname[0]) {
318 		strcat(buf, "@");
319 		strcat(buf, ds_snapname);
320 	}
321 	return (0);
322 }
323 
324 static int
325 enum_lookup(char *type, int val, const char *prefix, size_t size, char *out)
326 {
327 	const char *cp;
328 	size_t len = strlen(prefix);
329 	mdb_ctf_id_t enum_type;
330 
331 	if (mdb_ctf_lookup_by_name(type, &enum_type) != 0) {
332 		mdb_warn("Could not find enum for %s", type);
333 		return (-1);
334 	}
335 
336 	if ((cp = mdb_ctf_enum_name(enum_type, val)) != NULL) {
337 		if (strncmp(cp, prefix, len) == 0)
338 			cp += len;
339 		(void) strncpy(out, cp, size);
340 	} else {
341 		mdb_snprintf(out, size, "? (%d)", val);
342 	}
343 	return (0);
344 }
345 
346 /* ARGSUSED */
347 static int
348 zfs_params(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
349 {
350 	/*
351 	 * This table can be approximately generated by running:
352 	 * egrep "^[a-z0-9_]+ [a-z0-9_]+( =.*)?;" *.c | cut -d ' ' -f 2
353 	 */
354 	static const char *params[] = {
355 		"arc_lotsfree_percent",
356 		"arc_pages_pp_reserve",
357 		"arc_reduce_dnlc_percent",
358 		"arc_swapfs_reserve",
359 		"arc_zio_arena_free_shift",
360 		"dbuf_cache_hiwater_pct",
361 		"dbuf_cache_lowater_pct",
362 		"dbuf_cache_max_bytes",
363 		"dbuf_cache_max_shift",
364 		"ddt_zap_indirect_blockshift",
365 		"ddt_zap_leaf_blockshift",
366 		"ditto_same_vdev_distance_shift",
367 		"dmu_find_threads",
368 		"dmu_rescan_dnode_threshold",
369 		"dsl_scan_delay_completion",
370 		"fzap_default_block_shift",
371 		"l2arc_feed_again",
372 		"l2arc_feed_min_ms",
373 		"l2arc_feed_secs",
374 		"l2arc_headroom",
375 		"l2arc_headroom_boost",
376 		"l2arc_noprefetch",
377 		"l2arc_norw",
378 		"l2arc_write_boost",
379 		"l2arc_write_max",
380 		"metaslab_aliquot",
381 		"metaslab_bias_enabled",
382 		"metaslab_debug_load",
383 		"metaslab_debug_unload",
384 		"metaslab_df_alloc_threshold",
385 		"metaslab_df_free_pct",
386 		"metaslab_fragmentation_factor_enabled",
387 		"metaslab_force_ganging",
388 		"metaslab_lba_weighting_enabled",
389 		"metaslab_load_pct",
390 		"metaslab_min_alloc_size",
391 		"metaslab_ndf_clump_shift",
392 		"metaslab_preload_enabled",
393 		"metaslab_preload_limit",
394 		"metaslab_trace_enabled",
395 		"metaslab_trace_max_entries",
396 		"metaslab_unload_delay",
397 		"metaslabs_per_vdev",
398 		"reference_history",
399 		"reference_tracking_enable",
400 		"send_holes_without_birth_time",
401 		"spa_asize_inflation",
402 		"spa_load_verify_data",
403 		"spa_load_verify_maxinflight",
404 		"spa_load_verify_metadata",
405 		"spa_max_replication_override",
406 		"spa_min_slop",
407 		"spa_mode_global",
408 		"spa_slop_shift",
409 		"space_map_blksz",
410 		"vdev_mirror_shift",
411 		"zfetch_max_distance",
412 		"zfs_abd_chunk_size",
413 		"zfs_abd_scatter_enabled",
414 		"zfs_arc_average_blocksize",
415 		"zfs_arc_evict_batch_limit",
416 		"zfs_arc_grow_retry",
417 		"zfs_arc_max",
418 		"zfs_arc_meta_limit",
419 		"zfs_arc_meta_min",
420 		"zfs_arc_min",
421 		"zfs_arc_p_min_shift",
422 		"zfs_arc_shrink_shift",
423 		"zfs_async_block_max_blocks",
424 		"zfs_ccw_retry_interval",
425 		"zfs_commit_timeout_pct",
426 		"zfs_compressed_arc_enabled",
427 		"zfs_condense_indirect_commit_entry_delay_ticks",
428 		"zfs_condense_indirect_vdevs_enable",
429 		"zfs_condense_max_obsolete_bytes",
430 		"zfs_condense_min_mapping_bytes",
431 		"zfs_condense_pct",
432 		"zfs_dbgmsg_maxsize",
433 		"zfs_deadman_checktime_ms",
434 		"zfs_deadman_enabled",
435 		"zfs_deadman_synctime_ms",
436 		"zfs_dedup_prefetch",
437 		"zfs_default_bs",
438 		"zfs_default_ibs",
439 		"zfs_delay_max_ns",
440 		"zfs_delay_min_dirty_percent",
441 		"zfs_delay_resolution_ns",
442 		"zfs_delay_scale",
443 		"zfs_dirty_data_max",
444 		"zfs_dirty_data_max_max",
445 		"zfs_dirty_data_max_percent",
446 		"zfs_dirty_data_sync",
447 		"zfs_flags",
448 		"zfs_free_bpobj_enabled",
449 		"zfs_free_leak_on_eio",
450 		"zfs_free_min_time_ms",
451 		"zfs_fsync_sync_cnt",
452 		"zfs_immediate_write_sz",
453 		"zfs_indirect_condense_obsolete_pct",
454 		"zfs_lua_check_instrlimit_interval",
455 		"zfs_lua_max_instrlimit",
456 		"zfs_lua_max_memlimit",
457 		"zfs_max_recordsize",
458 		"zfs_mdcomp_disable",
459 		"zfs_metaslab_condense_block_threshold",
460 		"zfs_metaslab_fragmentation_threshold",
461 		"zfs_metaslab_segment_weight_enabled",
462 		"zfs_metaslab_switch_threshold",
463 		"zfs_mg_fragmentation_threshold",
464 		"zfs_mg_noalloc_threshold",
465 		"zfs_multilist_num_sublists",
466 		"zfs_no_scrub_io",
467 		"zfs_no_scrub_prefetch",
468 		"zfs_nocacheflush",
469 		"zfs_nopwrite_enabled",
470 		"zfs_object_remap_one_indirect_delay_ticks",
471 		"zfs_obsolete_min_time_ms",
472 		"zfs_pd_bytes_max",
473 		"zfs_per_txg_dirty_frees_percent",
474 		"zfs_prefetch_disable",
475 		"zfs_read_chunk_size",
476 		"zfs_recover",
477 		"zfs_recv_queue_length",
478 		"zfs_redundant_metadata_most_ditto_level",
479 		"zfs_remap_blkptr_enable",
480 		"zfs_remove_max_copy_bytes",
481 		"zfs_remove_max_segment",
482 		"zfs_resilver_delay",
483 		"zfs_resilver_min_time_ms",
484 		"zfs_scan_idle",
485 		"zfs_scan_min_time_ms",
486 		"zfs_scrub_delay",
487 		"zfs_scrub_limit",
488 		"zfs_send_corrupt_data",
489 		"zfs_send_queue_length",
490 		"zfs_send_set_freerecords_bit",
491 		"zfs_sync_pass_deferred_free",
492 		"zfs_sync_pass_dont_compress",
493 		"zfs_sync_pass_rewrite",
494 		"zfs_sync_taskq_batch_pct",
495 		"zfs_top_maxinflight",
496 		"zfs_txg_timeout",
497 		"zfs_vdev_aggregation_limit",
498 		"zfs_vdev_async_read_max_active",
499 		"zfs_vdev_async_read_min_active",
500 		"zfs_vdev_async_write_active_max_dirty_percent",
501 		"zfs_vdev_async_write_active_min_dirty_percent",
502 		"zfs_vdev_async_write_max_active",
503 		"zfs_vdev_async_write_min_active",
504 		"zfs_vdev_cache_bshift",
505 		"zfs_vdev_cache_max",
506 		"zfs_vdev_cache_size",
507 		"zfs_vdev_max_active",
508 		"zfs_vdev_queue_depth_pct",
509 		"zfs_vdev_read_gap_limit",
510 		"zfs_vdev_removal_max_active",
511 		"zfs_vdev_removal_min_active",
512 		"zfs_vdev_scrub_max_active",
513 		"zfs_vdev_scrub_min_active",
514 		"zfs_vdev_sync_read_max_active",
515 		"zfs_vdev_sync_read_min_active",
516 		"zfs_vdev_sync_write_max_active",
517 		"zfs_vdev_sync_write_min_active",
518 		"zfs_vdev_write_gap_limit",
519 		"zfs_write_implies_delete_child",
520 		"zfs_zil_clean_taskq_maxalloc",
521 		"zfs_zil_clean_taskq_minalloc",
522 		"zfs_zil_clean_taskq_nthr_pct",
523 		"zil_replay_disable",
524 		"zil_slog_bulk",
525 		"zio_buf_debug_limit",
526 		"zio_dva_throttle_enabled",
527 		"zio_injection_enabled",
528 		"zvol_immediate_write_sz",
529 		"zvol_maxphys",
530 		"zvol_unmap_enabled",
531 		"zvol_unmap_sync_enabled",
532 		"zfs_max_dataset_nesting",
533 	};
534 
535 	for (int i = 0; i < sizeof (params) / sizeof (params[0]); i++) {
536 		int sz;
537 		uint64_t val64;
538 		uint32_t *val32p = (uint32_t *)&val64;
539 
540 		sz = mdb_readvar(&val64, params[i]);
541 		if (sz == 4) {
542 			mdb_printf("%s = 0x%x\n", params[i], *val32p);
543 		} else if (sz == 8) {
544 			mdb_printf("%s = 0x%llx\n", params[i], val64);
545 		} else {
546 			mdb_warn("variable %s not found", params[i]);
547 		}
548 	}
549 
550 	return (DCMD_OK);
551 }
552 
553 /* ARGSUSED */
554 static int
555 dva(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
556 {
557 	dva_t dva;
558 	if (mdb_vread(&dva, sizeof (dva_t), addr) == -1) {
559 		mdb_warn("failed to read dva_t");
560 		return (DCMD_ERR);
561 	}
562 	mdb_printf("<%llu:%llx:%llx>\n",
563 	    (u_longlong_t)DVA_GET_VDEV(&dva),
564 	    (u_longlong_t)DVA_GET_OFFSET(&dva),
565 	    (u_longlong_t)DVA_GET_ASIZE(&dva));
566 
567 	return (DCMD_OK);
568 }
569 
570 /* ARGSUSED */
571 static int
572 blkptr(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
573 {
574 	char type[80], checksum[80], compress[80];
575 	blkptr_t blk, *bp = &blk;
576 	char buf[BP_SPRINTF_LEN];
577 
578 	if (mdb_vread(&blk, sizeof (blkptr_t), addr) == -1) {
579 		mdb_warn("failed to read blkptr_t");
580 		return (DCMD_ERR);
581 	}
582 
583 	if (enum_lookup("enum dmu_object_type", BP_GET_TYPE(bp), "DMU_OT_",
584 	    sizeof (type), type) == -1 ||
585 	    enum_lookup("enum zio_checksum", BP_GET_CHECKSUM(bp),
586 	    "ZIO_CHECKSUM_", sizeof (checksum), checksum) == -1 ||
587 	    enum_lookup("enum zio_compress", BP_GET_COMPRESS(bp),
588 	    "ZIO_COMPRESS_", sizeof (compress), compress) == -1) {
589 		mdb_warn("Could not find blkptr enumerated types");
590 		return (DCMD_ERR);
591 	}
592 
593 	SNPRINTF_BLKPTR(mdb_snprintf, '\n', buf, sizeof (buf), bp, type,
594 	    checksum, compress);
595 
596 	mdb_printf("%s\n", buf);
597 
598 	return (DCMD_OK);
599 }
600 
601 typedef struct mdb_dmu_buf_impl {
602 	struct {
603 		uint64_t db_object;
604 		uintptr_t db_data;
605 	} db;
606 	uintptr_t db_objset;
607 	uint64_t db_level;
608 	uint64_t db_blkid;
609 	struct {
610 		uint64_t rc_count;
611 	} db_holds;
612 } mdb_dmu_buf_impl_t;
613 
614 /* ARGSUSED */
615 static int
616 dbuf(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
617 {
618 	mdb_dmu_buf_impl_t db;
619 	char objectname[32];
620 	char blkidname[32];
621 	char path[ZFS_MAX_DATASET_NAME_LEN];
622 	int ptr_width = (int)(sizeof (void *)) * 2;
623 
624 	if (DCMD_HDRSPEC(flags))
625 		mdb_printf("%*s %8s %3s %9s %5s %s\n",
626 		    ptr_width, "addr", "object", "lvl", "blkid", "holds", "os");
627 
628 	if (mdb_ctf_vread(&db, ZFS_STRUCT "dmu_buf_impl", "mdb_dmu_buf_impl_t",
629 	    addr, 0) == -1)
630 		return (DCMD_ERR);
631 
632 	if (db.db.db_object == DMU_META_DNODE_OBJECT)
633 		(void) strcpy(objectname, "mdn");
634 	else
635 		(void) mdb_snprintf(objectname, sizeof (objectname), "%llx",
636 		    (u_longlong_t)db.db.db_object);
637 
638 	if (db.db_blkid == DMU_BONUS_BLKID)
639 		(void) strcpy(blkidname, "bonus");
640 	else
641 		(void) mdb_snprintf(blkidname, sizeof (blkidname), "%llx",
642 		    (u_longlong_t)db.db_blkid);
643 
644 	if (objset_name(db.db_objset, path)) {
645 		return (DCMD_ERR);
646 	}
647 
648 	mdb_printf("%*p %8s %3u %9s %5llu %s\n", ptr_width, addr,
649 	    objectname, (int)db.db_level, blkidname,
650 	    db.db_holds.rc_count, path);
651 
652 	return (DCMD_OK);
653 }
654 
655 /* ARGSUSED */
656 static int
657 dbuf_stats(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
658 {
659 #define	HISTOSZ 32
660 	uintptr_t dbp;
661 	dmu_buf_impl_t db;
662 	dbuf_hash_table_t ht;
663 	uint64_t bucket, ndbufs;
664 	uint64_t histo[HISTOSZ];
665 	uint64_t histo2[HISTOSZ];
666 	int i, maxidx;
667 
668 	if (mdb_readvar(&ht, "dbuf_hash_table") == -1) {
669 		mdb_warn("failed to read 'dbuf_hash_table'");
670 		return (DCMD_ERR);
671 	}
672 
673 	for (i = 0; i < HISTOSZ; i++) {
674 		histo[i] = 0;
675 		histo2[i] = 0;
676 	}
677 
678 	ndbufs = 0;
679 	for (bucket = 0; bucket < ht.hash_table_mask+1; bucket++) {
680 		int len;
681 
682 		if (mdb_vread(&dbp, sizeof (void *),
683 		    (uintptr_t)(ht.hash_table+bucket)) == -1) {
684 			mdb_warn("failed to read hash bucket %u at %p",
685 			    bucket, ht.hash_table+bucket);
686 			return (DCMD_ERR);
687 		}
688 
689 		len = 0;
690 		while (dbp != 0) {
691 			if (mdb_vread(&db, sizeof (dmu_buf_impl_t),
692 			    dbp) == -1) {
693 				mdb_warn("failed to read dbuf at %p", dbp);
694 				return (DCMD_ERR);
695 			}
696 			dbp = (uintptr_t)db.db_hash_next;
697 			for (i = MIN(len, HISTOSZ - 1); i >= 0; i--)
698 				histo2[i]++;
699 			len++;
700 			ndbufs++;
701 		}
702 
703 		if (len >= HISTOSZ)
704 			len = HISTOSZ-1;
705 		histo[len]++;
706 	}
707 
708 	mdb_printf("hash table has %llu buckets, %llu dbufs "
709 	    "(avg %llu buckets/dbuf)\n",
710 	    ht.hash_table_mask+1, ndbufs,
711 	    (ht.hash_table_mask+1)/ndbufs);
712 
713 	mdb_printf("\n");
714 	maxidx = 0;
715 	for (i = 0; i < HISTOSZ; i++)
716 		if (histo[i] > 0)
717 			maxidx = i;
718 	mdb_printf("hash chain length	number of buckets\n");
719 	for (i = 0; i <= maxidx; i++)
720 		mdb_printf("%u			%llu\n", i, histo[i]);
721 
722 	mdb_printf("\n");
723 	maxidx = 0;
724 	for (i = 0; i < HISTOSZ; i++)
725 		if (histo2[i] > 0)
726 			maxidx = i;
727 	mdb_printf("hash chain depth	number of dbufs\n");
728 	for (i = 0; i <= maxidx; i++)
729 		mdb_printf("%u or more		%llu	%llu%%\n",
730 		    i, histo2[i], histo2[i]*100/ndbufs);
731 
732 
733 	return (DCMD_OK);
734 }
735 
736 #define	CHAIN_END 0xffff
737 /*
738  * ::zap_leaf [-v]
739  *
740  * Print a zap_leaf_phys_t, assumed to be 16k
741  */
742 /* ARGSUSED */
743 static int
744 zap_leaf(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
745 {
746 	char buf[16*1024];
747 	int verbose = B_FALSE;
748 	int four = B_FALSE;
749 	dmu_buf_t l_dbuf;
750 	zap_leaf_t l;
751 	zap_leaf_phys_t *zlp = (void *)buf;
752 	int i;
753 
754 	if (mdb_getopts(argc, argv,
755 	    'v', MDB_OPT_SETBITS, TRUE, &verbose,
756 	    '4', MDB_OPT_SETBITS, TRUE, &four,
757 	    NULL) != argc)
758 		return (DCMD_USAGE);
759 
760 	l_dbuf.db_data = zlp;
761 	l.l_dbuf = &l_dbuf;
762 	l.l_bs = 14; /* assume 16k blocks */
763 	if (four)
764 		l.l_bs = 12;
765 
766 	if (!(flags & DCMD_ADDRSPEC)) {
767 		return (DCMD_USAGE);
768 	}
769 
770 	if (mdb_vread(buf, sizeof (buf), addr) == -1) {
771 		mdb_warn("failed to read zap_leaf_phys_t at %p", addr);
772 		return (DCMD_ERR);
773 	}
774 
775 	if (zlp->l_hdr.lh_block_type != ZBT_LEAF ||
776 	    zlp->l_hdr.lh_magic != ZAP_LEAF_MAGIC) {
777 		mdb_warn("This does not appear to be a zap_leaf_phys_t");
778 		return (DCMD_ERR);
779 	}
780 
781 	mdb_printf("zap_leaf_phys_t at %p:\n", addr);
782 	mdb_printf("    lh_prefix_len = %u\n", zlp->l_hdr.lh_prefix_len);
783 	mdb_printf("    lh_prefix = %llx\n", zlp->l_hdr.lh_prefix);
784 	mdb_printf("    lh_nentries = %u\n", zlp->l_hdr.lh_nentries);
785 	mdb_printf("    lh_nfree = %u\n", zlp->l_hdr.lh_nfree,
786 	    zlp->l_hdr.lh_nfree * 100 / (ZAP_LEAF_NUMCHUNKS(&l)));
787 	mdb_printf("    lh_freelist = %u\n", zlp->l_hdr.lh_freelist);
788 	mdb_printf("    lh_flags = %x (%s)\n", zlp->l_hdr.lh_flags,
789 	    zlp->l_hdr.lh_flags & ZLF_ENTRIES_CDSORTED ?
790 	    "ENTRIES_CDSORTED" : "");
791 
792 	if (verbose) {
793 		mdb_printf(" hash table:\n");
794 		for (i = 0; i < ZAP_LEAF_HASH_NUMENTRIES(&l); i++) {
795 			if (zlp->l_hash[i] != CHAIN_END)
796 				mdb_printf("    %u: %u\n", i, zlp->l_hash[i]);
797 		}
798 	}
799 
800 	mdb_printf(" chunks:\n");
801 	for (i = 0; i < ZAP_LEAF_NUMCHUNKS(&l); i++) {
802 		/* LINTED: alignment */
803 		zap_leaf_chunk_t *zlc = &ZAP_LEAF_CHUNK(&l, i);
804 		switch (zlc->l_entry.le_type) {
805 		case ZAP_CHUNK_FREE:
806 			if (verbose) {
807 				mdb_printf("    %u: free; lf_next = %u\n",
808 				    i, zlc->l_free.lf_next);
809 			}
810 			break;
811 		case ZAP_CHUNK_ENTRY:
812 			mdb_printf("    %u: entry\n", i);
813 			if (verbose) {
814 				mdb_printf("        le_next = %u\n",
815 				    zlc->l_entry.le_next);
816 			}
817 			mdb_printf("        le_name_chunk = %u\n",
818 			    zlc->l_entry.le_name_chunk);
819 			mdb_printf("        le_name_numints = %u\n",
820 			    zlc->l_entry.le_name_numints);
821 			mdb_printf("        le_value_chunk = %u\n",
822 			    zlc->l_entry.le_value_chunk);
823 			mdb_printf("        le_value_intlen = %u\n",
824 			    zlc->l_entry.le_value_intlen);
825 			mdb_printf("        le_value_numints = %u\n",
826 			    zlc->l_entry.le_value_numints);
827 			mdb_printf("        le_cd = %u\n",
828 			    zlc->l_entry.le_cd);
829 			mdb_printf("        le_hash = %llx\n",
830 			    zlc->l_entry.le_hash);
831 			break;
832 		case ZAP_CHUNK_ARRAY:
833 			mdb_printf("    %u: array", i);
834 			if (strisprint((char *)zlc->l_array.la_array))
835 				mdb_printf(" \"%s\"", zlc->l_array.la_array);
836 			mdb_printf("\n");
837 			if (verbose) {
838 				int j;
839 				mdb_printf("        ");
840 				for (j = 0; j < ZAP_LEAF_ARRAY_BYTES; j++) {
841 					mdb_printf("%02x ",
842 					    zlc->l_array.la_array[j]);
843 				}
844 				mdb_printf("\n");
845 			}
846 			if (zlc->l_array.la_next != CHAIN_END) {
847 				mdb_printf("        lf_next = %u\n",
848 				    zlc->l_array.la_next);
849 			}
850 			break;
851 		default:
852 			mdb_printf("    %u: undefined type %u\n",
853 			    zlc->l_entry.le_type);
854 		}
855 	}
856 
857 	return (DCMD_OK);
858 }
859 
860 typedef struct dbufs_data {
861 	mdb_ctf_id_t id;
862 	uint64_t objset;
863 	uint64_t object;
864 	uint64_t level;
865 	uint64_t blkid;
866 	char *osname;
867 } dbufs_data_t;
868 
869 #define	DBUFS_UNSET	(0xbaddcafedeadbeefULL)
870 
871 /* ARGSUSED */
872 static int
873 dbufs_cb(uintptr_t addr, const void *unknown, void *arg)
874 {
875 	dbufs_data_t *data = arg;
876 	uintptr_t objset;
877 	dmu_buf_t db;
878 	uint8_t level;
879 	uint64_t blkid;
880 	char osname[ZFS_MAX_DATASET_NAME_LEN];
881 
882 	if (GETMEMBID(addr, &data->id, db_objset, objset) ||
883 	    GETMEMBID(addr, &data->id, db, db) ||
884 	    GETMEMBID(addr, &data->id, db_level, level) ||
885 	    GETMEMBID(addr, &data->id, db_blkid, blkid)) {
886 		return (WALK_ERR);
887 	}
888 
889 	if ((data->objset == DBUFS_UNSET || data->objset == objset) &&
890 	    (data->osname == NULL || (objset_name(objset, osname) == 0 &&
891 	    strcmp(data->osname, osname) == 0)) &&
892 	    (data->object == DBUFS_UNSET || data->object == db.db_object) &&
893 	    (data->level == DBUFS_UNSET || data->level == level) &&
894 	    (data->blkid == DBUFS_UNSET || data->blkid == blkid)) {
895 		mdb_printf("%#lr\n", addr);
896 	}
897 	return (WALK_NEXT);
898 }
899 
900 /* ARGSUSED */
901 static int
902 dbufs(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
903 {
904 	dbufs_data_t data;
905 	char *object = NULL;
906 	char *blkid = NULL;
907 
908 	data.objset = data.object = data.level = data.blkid = DBUFS_UNSET;
909 	data.osname = NULL;
910 
911 	if (mdb_getopts(argc, argv,
912 	    'O', MDB_OPT_UINT64, &data.objset,
913 	    'n', MDB_OPT_STR, &data.osname,
914 	    'o', MDB_OPT_STR, &object,
915 	    'l', MDB_OPT_UINT64, &data.level,
916 	    'b', MDB_OPT_STR, &blkid) != argc) {
917 		return (DCMD_USAGE);
918 	}
919 
920 	if (object) {
921 		if (strcmp(object, "mdn") == 0) {
922 			data.object = DMU_META_DNODE_OBJECT;
923 		} else {
924 			data.object = mdb_strtoull(object);
925 		}
926 	}
927 
928 	if (blkid) {
929 		if (strcmp(blkid, "bonus") == 0) {
930 			data.blkid = DMU_BONUS_BLKID;
931 		} else {
932 			data.blkid = mdb_strtoull(blkid);
933 		}
934 	}
935 
936 	if (mdb_ctf_lookup_by_name(ZFS_STRUCT "dmu_buf_impl", &data.id) == -1) {
937 		mdb_warn("couldn't find struct dmu_buf_impl_t");
938 		return (DCMD_ERR);
939 	}
940 
941 	if (mdb_walk("dmu_buf_impl_t", dbufs_cb, &data) != 0) {
942 		mdb_warn("can't walk dbufs");
943 		return (DCMD_ERR);
944 	}
945 
946 	return (DCMD_OK);
947 }
948 
949 typedef struct abuf_find_data {
950 	dva_t dva;
951 	mdb_ctf_id_t id;
952 } abuf_find_data_t;
953 
954 /* ARGSUSED */
955 static int
956 abuf_find_cb(uintptr_t addr, const void *unknown, void *arg)
957 {
958 	abuf_find_data_t *data = arg;
959 	dva_t dva;
960 
961 	if (GETMEMBID(addr, &data->id, b_dva, dva)) {
962 		return (WALK_ERR);
963 	}
964 
965 	if (dva.dva_word[0] == data->dva.dva_word[0] &&
966 	    dva.dva_word[1] == data->dva.dva_word[1]) {
967 		mdb_printf("%#lr\n", addr);
968 	}
969 	return (WALK_NEXT);
970 }
971 
972 /* ARGSUSED */
973 static int
974 abuf_find(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
975 {
976 	abuf_find_data_t data;
977 	GElf_Sym sym;
978 	int i;
979 	const char *syms[] = {
980 		"ARC_mru",
981 		"ARC_mru_ghost",
982 		"ARC_mfu",
983 		"ARC_mfu_ghost",
984 	};
985 
986 	if (argc != 2)
987 		return (DCMD_USAGE);
988 
989 	for (i = 0; i < 2; i ++) {
990 		switch (argv[i].a_type) {
991 		case MDB_TYPE_STRING:
992 			data.dva.dva_word[i] = mdb_strtoull(argv[i].a_un.a_str);
993 			break;
994 		case MDB_TYPE_IMMEDIATE:
995 			data.dva.dva_word[i] = argv[i].a_un.a_val;
996 			break;
997 		default:
998 			return (DCMD_USAGE);
999 		}
1000 	}
1001 
1002 	if (mdb_ctf_lookup_by_name(ZFS_STRUCT "arc_buf_hdr", &data.id) == -1) {
1003 		mdb_warn("couldn't find struct arc_buf_hdr");
1004 		return (DCMD_ERR);
1005 	}
1006 
1007 	for (i = 0; i < sizeof (syms) / sizeof (syms[0]); i++) {
1008 		if (mdb_lookup_by_obj(ZFS_OBJ_NAME, syms[i], &sym)) {
1009 			mdb_warn("can't find symbol %s", syms[i]);
1010 			return (DCMD_ERR);
1011 		}
1012 
1013 		if (mdb_pwalk("list", abuf_find_cb, &data, sym.st_value) != 0) {
1014 			mdb_warn("can't walk %s", syms[i]);
1015 			return (DCMD_ERR);
1016 		}
1017 	}
1018 
1019 	return (DCMD_OK);
1020 }
1021 
1022 
1023 typedef struct dbgmsg_arg {
1024 	boolean_t da_verbose;
1025 	boolean_t da_address;
1026 } dbgmsg_arg_t;
1027 
1028 /* ARGSUSED */
1029 static int
1030 dbgmsg_cb(uintptr_t addr, const void *unknown, void *arg)
1031 {
1032 	static mdb_ctf_id_t id;
1033 	static boolean_t gotid;
1034 	static ulong_t off;
1035 
1036 	dbgmsg_arg_t *da = arg;
1037 	time_t timestamp;
1038 	char buf[1024];
1039 
1040 	if (!gotid) {
1041 		if (mdb_ctf_lookup_by_name(ZFS_STRUCT "zfs_dbgmsg", &id) ==
1042 		    -1) {
1043 			mdb_warn("couldn't find struct zfs_dbgmsg");
1044 			return (WALK_ERR);
1045 		}
1046 		gotid = TRUE;
1047 		if (mdb_ctf_offsetof(id, "zdm_msg", &off) == -1) {
1048 			mdb_warn("couldn't find zdm_msg");
1049 			return (WALK_ERR);
1050 		}
1051 		off /= 8;
1052 	}
1053 
1054 
1055 	if (GETMEMBID(addr, &id, zdm_timestamp, timestamp)) {
1056 		return (WALK_ERR);
1057 	}
1058 
1059 	if (mdb_readstr(buf, sizeof (buf), addr + off) == -1) {
1060 		mdb_warn("failed to read zdm_msg at %p\n", addr + off);
1061 		return (DCMD_ERR);
1062 	}
1063 
1064 	if (da->da_address)
1065 		mdb_printf("%p ", addr);
1066 	if (da->da_verbose)
1067 		mdb_printf("%Y ", timestamp);
1068 
1069 	mdb_printf("%s\n", buf);
1070 
1071 	if (da->da_verbose)
1072 		(void) mdb_call_dcmd("whatis", addr, DCMD_ADDRSPEC, 0, NULL);
1073 
1074 	return (WALK_NEXT);
1075 }
1076 
1077 /* ARGSUSED */
1078 static int
1079 dbgmsg(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1080 {
1081 	GElf_Sym sym;
1082 	dbgmsg_arg_t da = { 0 };
1083 
1084 	if (mdb_getopts(argc, argv,
1085 	    'v', MDB_OPT_SETBITS, B_TRUE, &da.da_verbose,
1086 	    'a', MDB_OPT_SETBITS, B_TRUE, &da.da_address,
1087 	    NULL) != argc)
1088 		return (DCMD_USAGE);
1089 
1090 	if (mdb_lookup_by_obj(ZFS_OBJ_NAME, "zfs_dbgmsgs", &sym)) {
1091 		mdb_warn("can't find zfs_dbgmsgs");
1092 		return (DCMD_ERR);
1093 	}
1094 
1095 	if (mdb_pwalk("list", dbgmsg_cb, &da, sym.st_value) != 0) {
1096 		mdb_warn("can't walk zfs_dbgmsgs");
1097 		return (DCMD_ERR);
1098 	}
1099 
1100 	return (DCMD_OK);
1101 }
1102 
1103 /*ARGSUSED*/
1104 static int
1105 arc_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1106 {
1107 	kstat_named_t *stats;
1108 	GElf_Sym sym;
1109 	int nstats, i;
1110 	uint_t opt_a = FALSE;
1111 	uint_t opt_b = FALSE;
1112 	uint_t shift = 0;
1113 	const char *suffix;
1114 
1115 	static const char *bytestats[] = {
1116 		"p", "c", "c_min", "c_max", "size", "duplicate_buffers_size",
1117 		"arc_meta_used", "arc_meta_limit", "arc_meta_max",
1118 		"arc_meta_min", "hdr_size", "data_size", "metadata_size",
1119 		"other_size", "anon_size", "anon_evictable_data",
1120 		"anon_evictable_metadata", "mru_size", "mru_evictable_data",
1121 		"mru_evictable_metadata", "mru_ghost_size",
1122 		"mru_ghost_evictable_data", "mru_ghost_evictable_metadata",
1123 		"mfu_size", "mfu_evictable_data", "mfu_evictable_metadata",
1124 		"mfu_ghost_size", "mfu_ghost_evictable_data",
1125 		"mfu_ghost_evictable_metadata", "evict_l2_cached",
1126 		"evict_l2_eligible", "evict_l2_ineligible", "l2_read_bytes",
1127 		"l2_write_bytes", "l2_size", "l2_asize", "l2_hdr_size",
1128 		"compressed_size", "uncompressed_size", "overhead_size",
1129 		NULL
1130 	};
1131 
1132 	static const char *extras[] = {
1133 		"arc_no_grow", "arc_tempreserve",
1134 		NULL
1135 	};
1136 
1137 	if (mdb_lookup_by_obj(ZFS_OBJ_NAME, "arc_stats", &sym) == -1) {
1138 		mdb_warn("failed to find 'arc_stats'");
1139 		return (DCMD_ERR);
1140 	}
1141 
1142 	stats = mdb_zalloc(sym.st_size, UM_SLEEP | UM_GC);
1143 
1144 	if (mdb_vread(stats, sym.st_size, sym.st_value) == -1) {
1145 		mdb_warn("couldn't read 'arc_stats' at %p", sym.st_value);
1146 		return (DCMD_ERR);
1147 	}
1148 
1149 	nstats = sym.st_size / sizeof (kstat_named_t);
1150 
1151 	/* NB: -a / opt_a are ignored for backwards compatability */
1152 	if (mdb_getopts(argc, argv,
1153 	    'a', MDB_OPT_SETBITS, TRUE, &opt_a,
1154 	    'b', MDB_OPT_SETBITS, TRUE, &opt_b,
1155 	    'k', MDB_OPT_SETBITS, 10, &shift,
1156 	    'm', MDB_OPT_SETBITS, 20, &shift,
1157 	    'g', MDB_OPT_SETBITS, 30, &shift,
1158 	    NULL) != argc)
1159 		return (DCMD_USAGE);
1160 
1161 	if (!opt_b && !shift)
1162 		shift = 20;
1163 
1164 	switch (shift) {
1165 	case 0:
1166 		suffix = "B";
1167 		break;
1168 	case 10:
1169 		suffix = "KB";
1170 		break;
1171 	case 20:
1172 		suffix = "MB";
1173 		break;
1174 	case 30:
1175 		suffix = "GB";
1176 		break;
1177 	default:
1178 		suffix = "XX";
1179 	}
1180 
1181 	for (i = 0; i < nstats; i++) {
1182 		int j;
1183 		boolean_t bytes = B_FALSE;
1184 
1185 		for (j = 0; bytestats[j]; j++) {
1186 			if (strcmp(stats[i].name, bytestats[j]) == 0) {
1187 				bytes = B_TRUE;
1188 				break;
1189 			}
1190 		}
1191 
1192 		if (bytes) {
1193 			mdb_printf("%-25s = %9llu %s\n", stats[i].name,
1194 			    stats[i].value.ui64 >> shift, suffix);
1195 		} else {
1196 			mdb_printf("%-25s = %9llu\n", stats[i].name,
1197 			    stats[i].value.ui64);
1198 		}
1199 	}
1200 
1201 	for (i = 0; extras[i]; i++) {
1202 		uint64_t buf;
1203 
1204 		if (mdb_lookup_by_obj(ZFS_OBJ_NAME, extras[i], &sym) == -1) {
1205 			mdb_warn("failed to find '%s'", extras[i]);
1206 			return (DCMD_ERR);
1207 		}
1208 
1209 		if (sym.st_size != sizeof (uint64_t) &&
1210 		    sym.st_size != sizeof (uint32_t)) {
1211 			mdb_warn("expected scalar for variable '%s'\n",
1212 			    extras[i]);
1213 			return (DCMD_ERR);
1214 		}
1215 
1216 		if (mdb_vread(&buf, sym.st_size, sym.st_value) == -1) {
1217 			mdb_warn("couldn't read '%s'", extras[i]);
1218 			return (DCMD_ERR);
1219 		}
1220 
1221 		mdb_printf("%-25s = ", extras[i]);
1222 
1223 		/* NB: all the 64-bit extras happen to be byte counts */
1224 		if (sym.st_size == sizeof (uint64_t))
1225 			mdb_printf("%9llu %s\n", buf >> shift, suffix);
1226 
1227 		if (sym.st_size == sizeof (uint32_t))
1228 			mdb_printf("%9d\n", *((uint32_t *)&buf));
1229 	}
1230 	return (DCMD_OK);
1231 }
1232 
1233 typedef struct mdb_spa_print {
1234 	pool_state_t spa_state;
1235 	char spa_name[ZFS_MAX_DATASET_NAME_LEN];
1236 	uintptr_t spa_normal_class;
1237 } mdb_spa_print_t;
1238 
1239 
1240 const char histo_stars[] = "****************************************";
1241 const int histo_width = sizeof (histo_stars) - 1;
1242 
1243 static void
1244 dump_histogram(const uint64_t *histo, int size, int offset)
1245 {
1246 	int i;
1247 	int minidx = size - 1;
1248 	int maxidx = 0;
1249 	uint64_t max = 0;
1250 
1251 	for (i = 0; i < size; i++) {
1252 		if (histo[i] > max)
1253 			max = histo[i];
1254 		if (histo[i] > 0 && i > maxidx)
1255 			maxidx = i;
1256 		if (histo[i] > 0 && i < minidx)
1257 			minidx = i;
1258 	}
1259 
1260 	if (max < histo_width)
1261 		max = histo_width;
1262 
1263 	for (i = minidx; i <= maxidx; i++) {
1264 		mdb_printf("%3u: %6llu %s\n",
1265 		    i + offset, (u_longlong_t)histo[i],
1266 		    &histo_stars[(max - histo[i]) * histo_width / max]);
1267 	}
1268 }
1269 
1270 typedef struct mdb_metaslab_class {
1271 	uint64_t mc_histogram[RANGE_TREE_HISTOGRAM_SIZE];
1272 } mdb_metaslab_class_t;
1273 
1274 /*
1275  * spa_class_histogram(uintptr_t class_addr)
1276  *
1277  * Prints free space histogram for a device class
1278  *
1279  * Returns DCMD_OK, or DCMD_ERR.
1280  */
1281 static int
1282 spa_class_histogram(uintptr_t class_addr)
1283 {
1284 	mdb_metaslab_class_t mc;
1285 	if (mdb_ctf_vread(&mc, "metaslab_class_t",
1286 	    "mdb_metaslab_class_t", class_addr, 0) == -1)
1287 		return (DCMD_ERR);
1288 
1289 	mdb_inc_indent(4);
1290 	dump_histogram(mc.mc_histogram, RANGE_TREE_HISTOGRAM_SIZE, 0);
1291 	mdb_dec_indent(4);
1292 	return (DCMD_OK);
1293 }
1294 
1295 /*
1296  * ::spa
1297  *
1298  *	-c	Print configuration information as well
1299  *	-v	Print vdev state
1300  *	-e	Print vdev error stats
1301  *	-m	Print vdev metaslab info
1302  *	-M	print vdev metaslab group info
1303  *	-h	Print histogram info (must be combined with -m or -M)
1304  *
1305  * Print a summarized spa_t.  When given no arguments, prints out a table of all
1306  * active pools on the system.
1307  */
1308 /* ARGSUSED */
1309 static int
1310 spa_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1311 {
1312 	const char *statetab[] = { "ACTIVE", "EXPORTED", "DESTROYED",
1313 		"SPARE", "L2CACHE", "UNINIT", "UNAVAIL", "POTENTIAL" };
1314 	const char *state;
1315 	int spa_flags = 0;
1316 
1317 	if (mdb_getopts(argc, argv,
1318 	    'c', MDB_OPT_SETBITS, SPA_FLAG_CONFIG, &spa_flags,
1319 	    'v', MDB_OPT_SETBITS, SPA_FLAG_VDEVS, &spa_flags,
1320 	    'e', MDB_OPT_SETBITS, SPA_FLAG_ERRORS, &spa_flags,
1321 	    'M', MDB_OPT_SETBITS, SPA_FLAG_METASLAB_GROUPS, &spa_flags,
1322 	    'm', MDB_OPT_SETBITS, SPA_FLAG_METASLABS, &spa_flags,
1323 	    'h', MDB_OPT_SETBITS, SPA_FLAG_HISTOGRAMS, &spa_flags,
1324 	    NULL) != argc)
1325 		return (DCMD_USAGE);
1326 
1327 	if (!(flags & DCMD_ADDRSPEC)) {
1328 		if (mdb_walk_dcmd("spa", "spa", argc, argv) == -1) {
1329 			mdb_warn("can't walk spa");
1330 			return (DCMD_ERR);
1331 		}
1332 
1333 		return (DCMD_OK);
1334 	}
1335 
1336 	if (flags & DCMD_PIPE_OUT) {
1337 		mdb_printf("%#lr\n", addr);
1338 		return (DCMD_OK);
1339 	}
1340 
1341 	if (DCMD_HDRSPEC(flags))
1342 		mdb_printf("%<u>%-?s %9s %-*s%</u>\n", "ADDR", "STATE",
1343 		    sizeof (uintptr_t) == 4 ? 60 : 52, "NAME");
1344 
1345 	mdb_spa_print_t spa;
1346 	if (mdb_ctf_vread(&spa, "spa_t", "mdb_spa_print_t", addr, 0) == -1)
1347 		return (DCMD_ERR);
1348 
1349 	if (spa.spa_state < 0 || spa.spa_state > POOL_STATE_UNAVAIL)
1350 		state = "UNKNOWN";
1351 	else
1352 		state = statetab[spa.spa_state];
1353 
1354 	mdb_printf("%0?p %9s %s\n", addr, state, spa.spa_name);
1355 	if (spa_flags & SPA_FLAG_HISTOGRAMS)
1356 		spa_class_histogram(spa.spa_normal_class);
1357 
1358 	if (spa_flags & SPA_FLAG_CONFIG) {
1359 		mdb_printf("\n");
1360 		mdb_inc_indent(4);
1361 		if (mdb_call_dcmd("spa_config", addr, flags, 0,
1362 		    NULL) != DCMD_OK)
1363 			return (DCMD_ERR);
1364 		mdb_dec_indent(4);
1365 	}
1366 
1367 	if (spa_flags & SPA_FLAG_ALL_VDEV) {
1368 		mdb_arg_t v;
1369 		char opts[100] = "-";
1370 		int args =
1371 		    (spa_flags | SPA_FLAG_VDEVS) == SPA_FLAG_VDEVS ? 0 : 1;
1372 
1373 		if (spa_flags & SPA_FLAG_ERRORS)
1374 			strcat(opts, "e");
1375 		if (spa_flags & SPA_FLAG_METASLABS)
1376 			strcat(opts, "m");
1377 		if (spa_flags & SPA_FLAG_METASLAB_GROUPS)
1378 			strcat(opts, "M");
1379 		if (spa_flags & SPA_FLAG_HISTOGRAMS)
1380 			strcat(opts, "h");
1381 
1382 		v.a_type = MDB_TYPE_STRING;
1383 		v.a_un.a_str = opts;
1384 
1385 		mdb_printf("\n");
1386 		mdb_inc_indent(4);
1387 		if (mdb_call_dcmd("spa_vdevs", addr, flags, args,
1388 		    &v) != DCMD_OK)
1389 			return (DCMD_ERR);
1390 		mdb_dec_indent(4);
1391 	}
1392 
1393 	return (DCMD_OK);
1394 }
1395 
1396 typedef struct mdb_spa_config_spa {
1397 	uintptr_t spa_config;
1398 } mdb_spa_config_spa_t;
1399 
1400 /*
1401  * ::spa_config
1402  *
1403  * Given a spa_t, print the configuration information stored in spa_config.
1404  * Since it's just an nvlist, format it as an indented list of name=value pairs.
1405  * We simply read the value of spa_config and pass off to ::nvlist.
1406  */
1407 /* ARGSUSED */
1408 static int
1409 spa_print_config(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1410 {
1411 	mdb_spa_config_spa_t spa;
1412 
1413 	if (argc != 0 || !(flags & DCMD_ADDRSPEC))
1414 		return (DCMD_USAGE);
1415 
1416 	if (mdb_ctf_vread(&spa, ZFS_STRUCT "spa", "mdb_spa_config_spa_t",
1417 	    addr, 0) == -1)
1418 		return (DCMD_ERR);
1419 
1420 	if (spa.spa_config == 0) {
1421 		mdb_printf("(none)\n");
1422 		return (DCMD_OK);
1423 	}
1424 
1425 	return (mdb_call_dcmd("nvlist", spa.spa_config, flags,
1426 	    0, NULL));
1427 }
1428 
1429 
1430 
1431 typedef struct mdb_range_tree {
1432 	uint64_t rt_space;
1433 } mdb_range_tree_t;
1434 
1435 typedef struct mdb_metaslab_group {
1436 	uint64_t mg_fragmentation;
1437 	uint64_t mg_histogram[RANGE_TREE_HISTOGRAM_SIZE];
1438 	uintptr_t mg_vd;
1439 } mdb_metaslab_group_t;
1440 
1441 typedef struct mdb_metaslab {
1442 	uint64_t ms_id;
1443 	uint64_t ms_start;
1444 	uint64_t ms_size;
1445 	int64_t ms_deferspace;
1446 	uint64_t ms_fragmentation;
1447 	uint64_t ms_weight;
1448 	uintptr_t ms_allocating[TXG_SIZE];
1449 	uintptr_t ms_checkpointing;
1450 	uintptr_t ms_freeing;
1451 	uintptr_t ms_freed;
1452 	uintptr_t ms_allocatable;
1453 	uintptr_t ms_sm;
1454 } mdb_metaslab_t;
1455 
1456 typedef struct mdb_space_map_phys_t {
1457 	int64_t smp_alloc;
1458 	uint64_t smp_histogram[SPACE_MAP_HISTOGRAM_SIZE];
1459 } mdb_space_map_phys_t;
1460 
1461 typedef struct mdb_space_map {
1462 	uint64_t sm_size;
1463 	uint8_t sm_shift;
1464 	int64_t sm_alloc;
1465 	uintptr_t sm_phys;
1466 } mdb_space_map_t;
1467 
1468 typedef struct mdb_vdev {
1469 	uintptr_t vdev_path;
1470 	uintptr_t vdev_ms;
1471 	uintptr_t vdev_ops;
1472 	uint64_t vdev_ms_count;
1473 	uint64_t vdev_id;
1474 	vdev_stat_t vdev_stat;
1475 } mdb_vdev_t;
1476 
1477 typedef struct mdb_vdev_ops {
1478 	char vdev_op_type[16];
1479 } mdb_vdev_ops_t;
1480 
1481 static int
1482 metaslab_stats(uintptr_t addr, int spa_flags)
1483 {
1484 	mdb_vdev_t vdev;
1485 	uintptr_t *vdev_ms;
1486 
1487 	if (mdb_ctf_vread(&vdev, "vdev_t", "mdb_vdev_t",
1488 	    (uintptr_t)addr, 0) == -1) {
1489 		mdb_warn("failed to read vdev at %p\n", addr);
1490 		return (DCMD_ERR);
1491 	}
1492 
1493 	mdb_inc_indent(4);
1494 	mdb_printf("%<u>%-?s %6s %20s %10s %9s%</u>\n", "ADDR", "ID",
1495 	    "OFFSET", "FREE", "FRAGMENTATION");
1496 
1497 	vdev_ms = mdb_alloc(vdev.vdev_ms_count * sizeof (void *),
1498 	    UM_SLEEP | UM_GC);
1499 	if (mdb_vread(vdev_ms, vdev.vdev_ms_count * sizeof (void *),
1500 	    (uintptr_t)vdev.vdev_ms) == -1) {
1501 		mdb_warn("failed to read vdev_ms at %p\n", vdev.vdev_ms);
1502 		return (DCMD_ERR);
1503 	}
1504 
1505 	for (int m = 0; m < vdev.vdev_ms_count; m++) {
1506 		mdb_metaslab_t ms;
1507 		mdb_space_map_t sm = { 0 };
1508 		char free[MDB_NICENUM_BUFLEN];
1509 
1510 		if (mdb_ctf_vread(&ms, "metaslab_t", "mdb_metaslab_t",
1511 		    (uintptr_t)vdev_ms[m], 0) == -1)
1512 			return (DCMD_ERR);
1513 
1514 		if (ms.ms_sm != 0 &&
1515 		    mdb_ctf_vread(&sm, "space_map_t", "mdb_space_map_t",
1516 		    ms.ms_sm, 0) == -1)
1517 			return (DCMD_ERR);
1518 
1519 		mdb_nicenum(ms.ms_size - sm.sm_alloc, free);
1520 
1521 		mdb_printf("%0?p %6llu %20llx %10s ", vdev_ms[m], ms.ms_id,
1522 		    ms.ms_start, free);
1523 		if (ms.ms_fragmentation == ZFS_FRAG_INVALID)
1524 			mdb_printf("%9s\n", "-");
1525 		else
1526 			mdb_printf("%9llu%%\n", ms.ms_fragmentation);
1527 
1528 		if ((spa_flags & SPA_FLAG_HISTOGRAMS) && ms.ms_sm != 0) {
1529 			mdb_space_map_phys_t smp;
1530 
1531 			if (sm.sm_phys == 0)
1532 				continue;
1533 
1534 			(void) mdb_ctf_vread(&smp, "space_map_phys_t",
1535 			    "mdb_space_map_phys_t", sm.sm_phys, 0);
1536 
1537 			dump_histogram(smp.smp_histogram,
1538 			    SPACE_MAP_HISTOGRAM_SIZE, sm.sm_shift);
1539 		}
1540 	}
1541 	mdb_dec_indent(4);
1542 	return (DCMD_OK);
1543 }
1544 
1545 static int
1546 metaslab_group_stats(uintptr_t addr, int spa_flags)
1547 {
1548 	mdb_metaslab_group_t mg;
1549 	if (mdb_ctf_vread(&mg, "metaslab_group_t", "mdb_metaslab_group_t",
1550 	    (uintptr_t)addr, 0) == -1) {
1551 		mdb_warn("failed to read vdev_mg at %p\n", addr);
1552 		return (DCMD_ERR);
1553 	}
1554 
1555 	mdb_inc_indent(4);
1556 	mdb_printf("%<u>%-?s %15s%</u>\n", "ADDR", "FRAGMENTATION");
1557 	if (mg.mg_fragmentation == ZFS_FRAG_INVALID)
1558 		mdb_printf("%0?p %15s\n", addr, "-");
1559 	else
1560 		mdb_printf("%0?p %15llu%%\n", addr, mg.mg_fragmentation);
1561 
1562 	if (spa_flags & SPA_FLAG_HISTOGRAMS)
1563 		dump_histogram(mg.mg_histogram, RANGE_TREE_HISTOGRAM_SIZE, 0);
1564 	mdb_dec_indent(4);
1565 	return (DCMD_OK);
1566 }
1567 
1568 /*
1569  * ::vdev
1570  *
1571  * Print out a summarized vdev_t, in the following form:
1572  *
1573  * ADDR             STATE	AUX            DESC
1574  * fffffffbcde23df0 HEALTHY	-              /dev/dsk/c0t0d0
1575  *
1576  * If '-r' is specified, recursively visit all children.
1577  *
1578  * With '-e', the statistics associated with the vdev are printed as well.
1579  */
1580 static int
1581 do_print_vdev(uintptr_t addr, int flags, int depth, boolean_t recursive,
1582     int spa_flags)
1583 {
1584 	vdev_t vdev;
1585 	char desc[MAXNAMELEN];
1586 	int c, children;
1587 	uintptr_t *child;
1588 	const char *state, *aux;
1589 
1590 	if (mdb_vread(&vdev, sizeof (vdev), (uintptr_t)addr) == -1) {
1591 		mdb_warn("failed to read vdev_t at %p\n", (uintptr_t)addr);
1592 		return (DCMD_ERR);
1593 	}
1594 
1595 	if (flags & DCMD_PIPE_OUT) {
1596 		mdb_printf("%#lr\n", addr);
1597 	} else {
1598 		if (vdev.vdev_path != NULL) {
1599 			if (mdb_readstr(desc, sizeof (desc),
1600 			    (uintptr_t)vdev.vdev_path) == -1) {
1601 				mdb_warn("failed to read vdev_path at %p\n",
1602 				    vdev.vdev_path);
1603 				return (DCMD_ERR);
1604 			}
1605 		} else if (vdev.vdev_ops != NULL) {
1606 			vdev_ops_t ops;
1607 			if (mdb_vread(&ops, sizeof (ops),
1608 			    (uintptr_t)vdev.vdev_ops) == -1) {
1609 				mdb_warn("failed to read vdev_ops at %p\n",
1610 				    vdev.vdev_ops);
1611 				return (DCMD_ERR);
1612 			}
1613 			(void) strcpy(desc, ops.vdev_op_type);
1614 		} else {
1615 			(void) strcpy(desc, "<unknown>");
1616 		}
1617 
1618 		if (depth == 0 && DCMD_HDRSPEC(flags))
1619 			mdb_printf("%<u>%-?s %-9s %-12s %-*s%</u>\n",
1620 			    "ADDR", "STATE", "AUX",
1621 			    sizeof (uintptr_t) == 4 ? 43 : 35,
1622 			    "DESCRIPTION");
1623 
1624 		mdb_printf("%0?p ", addr);
1625 
1626 		switch (vdev.vdev_state) {
1627 		case VDEV_STATE_CLOSED:
1628 			state = "CLOSED";
1629 			break;
1630 		case VDEV_STATE_OFFLINE:
1631 			state = "OFFLINE";
1632 			break;
1633 		case VDEV_STATE_CANT_OPEN:
1634 			state = "CANT_OPEN";
1635 			break;
1636 		case VDEV_STATE_DEGRADED:
1637 			state = "DEGRADED";
1638 			break;
1639 		case VDEV_STATE_HEALTHY:
1640 			state = "HEALTHY";
1641 			break;
1642 		case VDEV_STATE_REMOVED:
1643 			state = "REMOVED";
1644 			break;
1645 		case VDEV_STATE_FAULTED:
1646 			state = "FAULTED";
1647 			break;
1648 		default:
1649 			state = "UNKNOWN";
1650 			break;
1651 		}
1652 
1653 		switch (vdev.vdev_stat.vs_aux) {
1654 		case VDEV_AUX_NONE:
1655 			aux = "-";
1656 			break;
1657 		case VDEV_AUX_OPEN_FAILED:
1658 			aux = "OPEN_FAILED";
1659 			break;
1660 		case VDEV_AUX_CORRUPT_DATA:
1661 			aux = "CORRUPT_DATA";
1662 			break;
1663 		case VDEV_AUX_NO_REPLICAS:
1664 			aux = "NO_REPLICAS";
1665 			break;
1666 		case VDEV_AUX_BAD_GUID_SUM:
1667 			aux = "BAD_GUID_SUM";
1668 			break;
1669 		case VDEV_AUX_TOO_SMALL:
1670 			aux = "TOO_SMALL";
1671 			break;
1672 		case VDEV_AUX_BAD_LABEL:
1673 			aux = "BAD_LABEL";
1674 			break;
1675 		case VDEV_AUX_VERSION_NEWER:
1676 			aux = "VERS_NEWER";
1677 			break;
1678 		case VDEV_AUX_VERSION_OLDER:
1679 			aux = "VERS_OLDER";
1680 			break;
1681 		case VDEV_AUX_UNSUP_FEAT:
1682 			aux = "UNSUP_FEAT";
1683 			break;
1684 		case VDEV_AUX_SPARED:
1685 			aux = "SPARED";
1686 			break;
1687 		case VDEV_AUX_ERR_EXCEEDED:
1688 			aux = "ERR_EXCEEDED";
1689 			break;
1690 		case VDEV_AUX_IO_FAILURE:
1691 			aux = "IO_FAILURE";
1692 			break;
1693 		case VDEV_AUX_BAD_LOG:
1694 			aux = "BAD_LOG";
1695 			break;
1696 		case VDEV_AUX_EXTERNAL:
1697 			aux = "EXTERNAL";
1698 			break;
1699 		case VDEV_AUX_SPLIT_POOL:
1700 			aux = "SPLIT_POOL";
1701 			break;
1702 		case VDEV_AUX_CHILDREN_OFFLINE:
1703 			aux = "CHILDREN_OFFLINE";
1704 			break;
1705 		default:
1706 			aux = "UNKNOWN";
1707 			break;
1708 		}
1709 
1710 		mdb_printf("%-9s %-12s %*s%s\n", state, aux, depth, "", desc);
1711 
1712 		if (spa_flags & SPA_FLAG_ERRORS) {
1713 			vdev_stat_t *vs = &vdev.vdev_stat;
1714 			int i;
1715 
1716 			mdb_inc_indent(4);
1717 			mdb_printf("\n");
1718 			mdb_printf("%<u>       %12s %12s %12s %12s "
1719 			    "%12s%</u>\n", "READ", "WRITE", "FREE", "CLAIM",
1720 			    "IOCTL");
1721 			mdb_printf("OPS     ");
1722 			for (i = 1; i < ZIO_TYPES; i++)
1723 				mdb_printf("%11#llx%s", vs->vs_ops[i],
1724 				    i == ZIO_TYPES - 1 ? "" : "  ");
1725 			mdb_printf("\n");
1726 			mdb_printf("BYTES   ");
1727 			for (i = 1; i < ZIO_TYPES; i++)
1728 				mdb_printf("%11#llx%s", vs->vs_bytes[i],
1729 				    i == ZIO_TYPES - 1 ? "" : "  ");
1730 
1731 
1732 			mdb_printf("\n");
1733 			mdb_printf("EREAD    %10#llx\n", vs->vs_read_errors);
1734 			mdb_printf("EWRITE   %10#llx\n", vs->vs_write_errors);
1735 			mdb_printf("ECKSUM   %10#llx\n",
1736 			    vs->vs_checksum_errors);
1737 			mdb_dec_indent(4);
1738 			mdb_printf("\n");
1739 		}
1740 
1741 		if (spa_flags & SPA_FLAG_METASLAB_GROUPS &&
1742 		    vdev.vdev_mg != NULL) {
1743 			metaslab_group_stats((uintptr_t)vdev.vdev_mg,
1744 			    spa_flags);
1745 		}
1746 		if (spa_flags & SPA_FLAG_METASLABS && vdev.vdev_ms != NULL) {
1747 			metaslab_stats((uintptr_t)addr, spa_flags);
1748 		}
1749 	}
1750 
1751 	children = vdev.vdev_children;
1752 
1753 	if (children == 0 || !recursive)
1754 		return (DCMD_OK);
1755 
1756 	child = mdb_alloc(children * sizeof (void *), UM_SLEEP | UM_GC);
1757 	if (mdb_vread(child, children * sizeof (void *),
1758 	    (uintptr_t)vdev.vdev_child) == -1) {
1759 		mdb_warn("failed to read vdev children at %p", vdev.vdev_child);
1760 		return (DCMD_ERR);
1761 	}
1762 
1763 	for (c = 0; c < children; c++) {
1764 		if (do_print_vdev(child[c], flags, depth + 2, recursive,
1765 		    spa_flags)) {
1766 			return (DCMD_ERR);
1767 		}
1768 	}
1769 
1770 	return (DCMD_OK);
1771 }
1772 
1773 static int
1774 vdev_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1775 {
1776 	uint64_t depth = 0;
1777 	boolean_t recursive = B_FALSE;
1778 	int spa_flags = 0;
1779 
1780 	if (mdb_getopts(argc, argv,
1781 	    'e', MDB_OPT_SETBITS, SPA_FLAG_ERRORS, &spa_flags,
1782 	    'm', MDB_OPT_SETBITS, SPA_FLAG_METASLABS, &spa_flags,
1783 	    'M', MDB_OPT_SETBITS, SPA_FLAG_METASLAB_GROUPS, &spa_flags,
1784 	    'h', MDB_OPT_SETBITS, SPA_FLAG_HISTOGRAMS, &spa_flags,
1785 	    'r', MDB_OPT_SETBITS, TRUE, &recursive,
1786 	    'd', MDB_OPT_UINT64, &depth, NULL) != argc)
1787 		return (DCMD_USAGE);
1788 
1789 	if (!(flags & DCMD_ADDRSPEC)) {
1790 		mdb_warn("no vdev_t address given\n");
1791 		return (DCMD_ERR);
1792 	}
1793 
1794 	return (do_print_vdev(addr, flags, (int)depth, recursive, spa_flags));
1795 }
1796 
1797 typedef struct mdb_metaslab_alloc_trace {
1798 	uintptr_t mat_mg;
1799 	uintptr_t mat_msp;
1800 	uint64_t mat_size;
1801 	uint64_t mat_weight;
1802 	uint64_t mat_offset;
1803 	uint32_t mat_dva_id;
1804 	int mat_allocator;
1805 } mdb_metaslab_alloc_trace_t;
1806 
1807 static void
1808 metaslab_print_weight(uint64_t weight)
1809 {
1810 	char buf[100];
1811 
1812 	if (WEIGHT_IS_SPACEBASED(weight)) {
1813 		mdb_nicenum(
1814 		    weight & ~(METASLAB_ACTIVE_MASK | METASLAB_WEIGHT_TYPE),
1815 		    buf);
1816 	} else {
1817 		char size[MDB_NICENUM_BUFLEN];
1818 		mdb_nicenum(1ULL << WEIGHT_GET_INDEX(weight), size);
1819 		(void) mdb_snprintf(buf, sizeof (buf), "%llu x %s",
1820 		    WEIGHT_GET_COUNT(weight), size);
1821 	}
1822 	mdb_printf("%11s ", buf);
1823 }
1824 
1825 /* ARGSUSED */
1826 static int
1827 metaslab_weight(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1828 {
1829 	uint64_t weight = 0;
1830 	char active;
1831 
1832 	if (argc == 0 && (flags & DCMD_ADDRSPEC)) {
1833 		if (mdb_vread(&weight, sizeof (uint64_t), addr) == -1) {
1834 			mdb_warn("failed to read weight at %p\n", addr);
1835 			return (DCMD_ERR);
1836 		}
1837 	} else if (argc == 1 && !(flags & DCMD_ADDRSPEC)) {
1838 		weight = (argv[0].a_type == MDB_TYPE_IMMEDIATE) ?
1839 		    argv[0].a_un.a_val : mdb_strtoull(argv[0].a_un.a_str);
1840 	} else {
1841 		return (DCMD_USAGE);
1842 	}
1843 
1844 	if (DCMD_HDRSPEC(flags)) {
1845 		mdb_printf("%<u>%-6s %9s %9s%</u>\n",
1846 		    "ACTIVE", "ALGORITHM", "WEIGHT");
1847 	}
1848 
1849 	if (weight & METASLAB_WEIGHT_PRIMARY)
1850 		active = 'P';
1851 	else if (weight & METASLAB_WEIGHT_SECONDARY)
1852 		active = 'S';
1853 	else
1854 		active = '-';
1855 	mdb_printf("%6c %8s ", active,
1856 	    WEIGHT_IS_SPACEBASED(weight) ? "SPACE" : "SEGMENT");
1857 	metaslab_print_weight(weight);
1858 	mdb_printf("\n");
1859 
1860 	return (DCMD_OK);
1861 }
1862 
1863 /* ARGSUSED */
1864 static int
1865 metaslab_trace(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1866 {
1867 	mdb_metaslab_alloc_trace_t mat;
1868 	mdb_metaslab_group_t mg = { 0 };
1869 	char result_type[100];
1870 
1871 	if (mdb_ctf_vread(&mat, "metaslab_alloc_trace_t",
1872 	    "mdb_metaslab_alloc_trace_t", addr, 0) == -1) {
1873 		return (DCMD_ERR);
1874 	}
1875 
1876 	if (!(flags & DCMD_PIPE_OUT) && DCMD_HDRSPEC(flags)) {
1877 		mdb_printf("%<u>%6s %6s %8s %11s %11s %18s %18s%</u>\n",
1878 		    "MSID", "DVA", "ASIZE", "ALLOCATOR", "WEIGHT", "RESULT",
1879 		    "VDEV");
1880 	}
1881 
1882 	if (mat.mat_msp != 0) {
1883 		mdb_metaslab_t ms;
1884 
1885 		if (mdb_ctf_vread(&ms, "metaslab_t", "mdb_metaslab_t",
1886 		    mat.mat_msp, 0) == -1) {
1887 			return (DCMD_ERR);
1888 		}
1889 		mdb_printf("%6llu ", ms.ms_id);
1890 	} else {
1891 		mdb_printf("%6s ", "-");
1892 	}
1893 
1894 	mdb_printf("%6d %8llx %11llx ", mat.mat_dva_id, mat.mat_size,
1895 	    mat.mat_allocator);
1896 
1897 	metaslab_print_weight(mat.mat_weight);
1898 
1899 	if ((int64_t)mat.mat_offset < 0) {
1900 		if (enum_lookup("enum trace_alloc_type", mat.mat_offset,
1901 		    "TRACE_", sizeof (result_type), result_type) == -1) {
1902 			mdb_warn("Could not find enum for trace_alloc_type");
1903 			return (DCMD_ERR);
1904 		}
1905 		mdb_printf("%18s ", result_type);
1906 	} else {
1907 		mdb_printf("%<b>%18llx%</b> ", mat.mat_offset);
1908 	}
1909 
1910 	if (mat.mat_mg != 0 &&
1911 	    mdb_ctf_vread(&mg, "metaslab_group_t", "mdb_metaslab_group_t",
1912 	    mat.mat_mg, 0) == -1) {
1913 		return (DCMD_ERR);
1914 	}
1915 
1916 	if (mg.mg_vd != 0) {
1917 		mdb_vdev_t vdev;
1918 		char desc[MAXNAMELEN];
1919 
1920 		if (mdb_ctf_vread(&vdev, "vdev_t", "mdb_vdev_t",
1921 		    mg.mg_vd, 0) == -1) {
1922 			return (DCMD_ERR);
1923 		}
1924 
1925 		if (vdev.vdev_path != 0) {
1926 			char path[MAXNAMELEN];
1927 
1928 			if (mdb_readstr(path, sizeof (path),
1929 			    vdev.vdev_path) == -1) {
1930 				mdb_warn("failed to read vdev_path at %p\n",
1931 				    vdev.vdev_path);
1932 				return (DCMD_ERR);
1933 			}
1934 			char *slash;
1935 			if ((slash = strrchr(path, '/')) != NULL) {
1936 				strcpy(desc, slash + 1);
1937 			} else {
1938 				strcpy(desc, path);
1939 			}
1940 		} else if (vdev.vdev_ops != 0) {
1941 			mdb_vdev_ops_t ops;
1942 			if (mdb_ctf_vread(&ops, "vdev_ops_t", "mdb_vdev_ops_t",
1943 			    vdev.vdev_ops, 0) == -1) {
1944 				mdb_warn("failed to read vdev_ops at %p\n",
1945 				    vdev.vdev_ops);
1946 				return (DCMD_ERR);
1947 			}
1948 			(void) mdb_snprintf(desc, sizeof (desc),
1949 			    "%s-%llu", ops.vdev_op_type, vdev.vdev_id);
1950 		} else {
1951 			(void) strcpy(desc, "<unknown>");
1952 		}
1953 		mdb_printf("%18s\n", desc);
1954 	}
1955 
1956 	return (DCMD_OK);
1957 }
1958 
1959 typedef struct metaslab_walk_data {
1960 	uint64_t mw_numvdevs;
1961 	uintptr_t *mw_vdevs;
1962 	int mw_curvdev;
1963 	uint64_t mw_nummss;
1964 	uintptr_t *mw_mss;
1965 	int mw_curms;
1966 } metaslab_walk_data_t;
1967 
1968 static int
1969 metaslab_walk_step(mdb_walk_state_t *wsp)
1970 {
1971 	metaslab_walk_data_t *mw = wsp->walk_data;
1972 	metaslab_t ms;
1973 	uintptr_t msp;
1974 
1975 	if (mw->mw_curvdev >= mw->mw_numvdevs)
1976 		return (WALK_DONE);
1977 
1978 	if (mw->mw_mss == NULL) {
1979 		uintptr_t mssp;
1980 		uintptr_t vdevp;
1981 
1982 		ASSERT(mw->mw_curms == 0);
1983 		ASSERT(mw->mw_nummss == 0);
1984 
1985 		vdevp = mw->mw_vdevs[mw->mw_curvdev];
1986 		if (GETMEMB(vdevp, "vdev", vdev_ms, mssp) ||
1987 		    GETMEMB(vdevp, "vdev", vdev_ms_count, mw->mw_nummss)) {
1988 			return (WALK_ERR);
1989 		}
1990 
1991 		mw->mw_mss = mdb_alloc(mw->mw_nummss * sizeof (void*),
1992 		    UM_SLEEP | UM_GC);
1993 		if (mdb_vread(mw->mw_mss, mw->mw_nummss * sizeof (void*),
1994 		    mssp) == -1) {
1995 			mdb_warn("failed to read vdev_ms at %p", mssp);
1996 			return (WALK_ERR);
1997 		}
1998 	}
1999 
2000 	if (mw->mw_curms >= mw->mw_nummss) {
2001 		mw->mw_mss = NULL;
2002 		mw->mw_curms = 0;
2003 		mw->mw_nummss = 0;
2004 		mw->mw_curvdev++;
2005 		return (WALK_NEXT);
2006 	}
2007 
2008 	msp = mw->mw_mss[mw->mw_curms];
2009 	if (mdb_vread(&ms, sizeof (metaslab_t), msp) == -1) {
2010 		mdb_warn("failed to read metaslab_t at %p", msp);
2011 		return (WALK_ERR);
2012 	}
2013 
2014 	mw->mw_curms++;
2015 
2016 	return (wsp->walk_callback(msp, &ms, wsp->walk_cbdata));
2017 }
2018 
2019 static int
2020 metaslab_walk_init(mdb_walk_state_t *wsp)
2021 {
2022 	metaslab_walk_data_t *mw;
2023 	uintptr_t root_vdevp;
2024 	uintptr_t childp;
2025 
2026 	if (wsp->walk_addr == 0) {
2027 		mdb_warn("must supply address of spa_t\n");
2028 		return (WALK_ERR);
2029 	}
2030 
2031 	mw = mdb_zalloc(sizeof (metaslab_walk_data_t), UM_SLEEP | UM_GC);
2032 
2033 	if (GETMEMB(wsp->walk_addr, "spa", spa_root_vdev, root_vdevp) ||
2034 	    GETMEMB(root_vdevp, "vdev", vdev_children, mw->mw_numvdevs) ||
2035 	    GETMEMB(root_vdevp, "vdev", vdev_child, childp)) {
2036 		return (DCMD_ERR);
2037 	}
2038 
2039 	mw->mw_vdevs = mdb_alloc(mw->mw_numvdevs * sizeof (void *),
2040 	    UM_SLEEP | UM_GC);
2041 	if (mdb_vread(mw->mw_vdevs, mw->mw_numvdevs * sizeof (void *),
2042 	    childp) == -1) {
2043 		mdb_warn("failed to read root vdev children at %p", childp);
2044 		return (DCMD_ERR);
2045 	}
2046 
2047 	wsp->walk_data = mw;
2048 
2049 	return (WALK_NEXT);
2050 }
2051 
2052 typedef struct mdb_spa {
2053 	uintptr_t spa_dsl_pool;
2054 	uintptr_t spa_root_vdev;
2055 } mdb_spa_t;
2056 
2057 typedef struct mdb_dsl_pool {
2058 	uintptr_t dp_root_dir;
2059 } mdb_dsl_pool_t;
2060 
2061 typedef struct mdb_dsl_dir {
2062 	uintptr_t dd_dbuf;
2063 	int64_t dd_space_towrite[TXG_SIZE];
2064 } mdb_dsl_dir_t;
2065 
2066 typedef struct mdb_dsl_dir_phys {
2067 	uint64_t dd_used_bytes;
2068 	uint64_t dd_compressed_bytes;
2069 	uint64_t dd_uncompressed_bytes;
2070 } mdb_dsl_dir_phys_t;
2071 
2072 typedef struct space_data {
2073 	uint64_t ms_allocating[TXG_SIZE];
2074 	uint64_t ms_checkpointing;
2075 	uint64_t ms_freeing;
2076 	uint64_t ms_freed;
2077 	uint64_t ms_allocatable;
2078 	int64_t ms_deferspace;
2079 	uint64_t avail;
2080 	uint64_t nowavail;
2081 } space_data_t;
2082 
2083 /* ARGSUSED */
2084 static int
2085 space_cb(uintptr_t addr, const void *unknown, void *arg)
2086 {
2087 	space_data_t *sd = arg;
2088 	mdb_metaslab_t ms;
2089 	mdb_range_tree_t rt;
2090 	mdb_space_map_t sm = { 0 };
2091 	mdb_space_map_phys_t smp = { 0 };
2092 	int i;
2093 
2094 	if (mdb_ctf_vread(&ms, "metaslab_t", "mdb_metaslab_t",
2095 	    addr, 0) == -1)
2096 		return (WALK_ERR);
2097 
2098 	for (i = 0; i < TXG_SIZE; i++) {
2099 		if (mdb_ctf_vread(&rt, "range_tree_t",
2100 		    "mdb_range_tree_t", ms.ms_allocating[i], 0) == -1)
2101 			return (WALK_ERR);
2102 
2103 		sd->ms_allocating[i] += rt.rt_space;
2104 
2105 	}
2106 
2107 	if (mdb_ctf_vread(&rt, "range_tree_t",
2108 	    "mdb_range_tree_t", ms.ms_checkpointing, 0) == -1)
2109 		return (WALK_ERR);
2110 	sd->ms_checkpointing += rt.rt_space;
2111 
2112 	if (mdb_ctf_vread(&rt, "range_tree_t",
2113 	    "mdb_range_tree_t", ms.ms_freeing, 0) == -1)
2114 		return (WALK_ERR);
2115 	sd->ms_freeing += rt.rt_space;
2116 
2117 	if (mdb_ctf_vread(&rt, "range_tree_t",
2118 	    "mdb_range_tree_t", ms.ms_freed, 0) == -1)
2119 		return (WALK_ERR);
2120 	sd->ms_freed += rt.rt_space;
2121 
2122 	if (mdb_ctf_vread(&rt, "range_tree_t",
2123 	    "mdb_range_tree_t", ms.ms_allocatable, 0) == -1)
2124 		return (WALK_ERR);
2125 	sd->ms_allocatable += rt.rt_space;
2126 
2127 	if (ms.ms_sm != 0 &&
2128 	    mdb_ctf_vread(&sm, "space_map_t",
2129 	    "mdb_space_map_t", ms.ms_sm, 0) == -1)
2130 		return (WALK_ERR);
2131 
2132 	if (sm.sm_phys != 0) {
2133 		(void) mdb_ctf_vread(&smp, "space_map_phys_t",
2134 		    "mdb_space_map_phys_t", sm.sm_phys, 0);
2135 	}
2136 
2137 	sd->ms_deferspace += ms.ms_deferspace;
2138 	sd->avail += sm.sm_size - sm.sm_alloc;
2139 	sd->nowavail += sm.sm_size - smp.smp_alloc;
2140 
2141 	return (WALK_NEXT);
2142 }
2143 
2144 /*
2145  * ::spa_space [-b]
2146  *
2147  * Given a spa_t, print out it's on-disk space usage and in-core
2148  * estimates of future usage.  If -b is given, print space in bytes.
2149  * Otherwise print in megabytes.
2150  */
2151 /* ARGSUSED */
2152 static int
2153 spa_space(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2154 {
2155 	mdb_spa_t spa;
2156 	mdb_dsl_pool_t dp;
2157 	mdb_dsl_dir_t dd;
2158 	mdb_dmu_buf_impl_t db;
2159 	mdb_dsl_dir_phys_t dsp;
2160 	space_data_t sd;
2161 	int shift = 20;
2162 	char *suffix = "M";
2163 	int bytes = B_FALSE;
2164 
2165 	if (mdb_getopts(argc, argv, 'b', MDB_OPT_SETBITS, TRUE, &bytes, NULL) !=
2166 	    argc)
2167 		return (DCMD_USAGE);
2168 	if (!(flags & DCMD_ADDRSPEC))
2169 		return (DCMD_USAGE);
2170 
2171 	if (bytes) {
2172 		shift = 0;
2173 		suffix = "";
2174 	}
2175 
2176 	if (mdb_ctf_vread(&spa, ZFS_STRUCT "spa", "mdb_spa_t",
2177 	    addr, 0) == -1 ||
2178 	    mdb_ctf_vread(&dp, ZFS_STRUCT "dsl_pool", "mdb_dsl_pool_t",
2179 	    spa.spa_dsl_pool, 0) == -1 ||
2180 	    mdb_ctf_vread(&dd, ZFS_STRUCT "dsl_dir", "mdb_dsl_dir_t",
2181 	    dp.dp_root_dir, 0) == -1 ||
2182 	    mdb_ctf_vread(&db, ZFS_STRUCT "dmu_buf_impl", "mdb_dmu_buf_impl_t",
2183 	    dd.dd_dbuf, 0) == -1 ||
2184 	    mdb_ctf_vread(&dsp, ZFS_STRUCT "dsl_dir_phys",
2185 	    "mdb_dsl_dir_phys_t", db.db.db_data, 0) == -1) {
2186 		return (DCMD_ERR);
2187 	}
2188 
2189 	mdb_printf("dd_space_towrite = %llu%s %llu%s %llu%s %llu%s\n",
2190 	    dd.dd_space_towrite[0] >> shift, suffix,
2191 	    dd.dd_space_towrite[1] >> shift, suffix,
2192 	    dd.dd_space_towrite[2] >> shift, suffix,
2193 	    dd.dd_space_towrite[3] >> shift, suffix);
2194 
2195 	mdb_printf("dd_phys.dd_used_bytes = %llu%s\n",
2196 	    dsp.dd_used_bytes >> shift, suffix);
2197 	mdb_printf("dd_phys.dd_compressed_bytes = %llu%s\n",
2198 	    dsp.dd_compressed_bytes >> shift, suffix);
2199 	mdb_printf("dd_phys.dd_uncompressed_bytes = %llu%s\n",
2200 	    dsp.dd_uncompressed_bytes >> shift, suffix);
2201 
2202 	bzero(&sd, sizeof (sd));
2203 	if (mdb_pwalk("metaslab", space_cb, &sd, addr) != 0) {
2204 		mdb_warn("can't walk metaslabs");
2205 		return (DCMD_ERR);
2206 	}
2207 
2208 	mdb_printf("ms_allocmap = %llu%s %llu%s %llu%s %llu%s\n",
2209 	    sd.ms_allocating[0] >> shift, suffix,
2210 	    sd.ms_allocating[1] >> shift, suffix,
2211 	    sd.ms_allocating[2] >> shift, suffix,
2212 	    sd.ms_allocating[3] >> shift, suffix);
2213 	mdb_printf("ms_checkpointing = %llu%s\n",
2214 	    sd.ms_checkpointing >> shift, suffix);
2215 	mdb_printf("ms_freeing = %llu%s\n",
2216 	    sd.ms_freeing >> shift, suffix);
2217 	mdb_printf("ms_freed = %llu%s\n",
2218 	    sd.ms_freed >> shift, suffix);
2219 	mdb_printf("ms_allocatable = %llu%s\n",
2220 	    sd.ms_allocatable >> shift, suffix);
2221 	mdb_printf("ms_deferspace = %llu%s\n",
2222 	    sd.ms_deferspace >> shift, suffix);
2223 	mdb_printf("last synced avail = %llu%s\n",
2224 	    sd.avail >> shift, suffix);
2225 	mdb_printf("current syncing avail = %llu%s\n",
2226 	    sd.nowavail >> shift, suffix);
2227 
2228 	return (DCMD_OK);
2229 }
2230 
2231 typedef struct mdb_spa_aux_vdev {
2232 	int sav_count;
2233 	uintptr_t sav_vdevs;
2234 } mdb_spa_aux_vdev_t;
2235 
2236 typedef struct mdb_spa_vdevs {
2237 	uintptr_t spa_root_vdev;
2238 	mdb_spa_aux_vdev_t spa_l2cache;
2239 	mdb_spa_aux_vdev_t spa_spares;
2240 } mdb_spa_vdevs_t;
2241 
2242 static int
2243 spa_print_aux(mdb_spa_aux_vdev_t *sav, uint_t flags, mdb_arg_t *v,
2244     const char *name)
2245 {
2246 	uintptr_t *aux;
2247 	size_t len;
2248 	int ret, i;
2249 
2250 	/*
2251 	 * Iterate over aux vdevs and print those out as well.  This is a
2252 	 * little annoying because we don't have a root vdev to pass to ::vdev.
2253 	 * Instead, we print a single line and then call it for each child
2254 	 * vdev.
2255 	 */
2256 	if (sav->sav_count != 0) {
2257 		v[1].a_type = MDB_TYPE_STRING;
2258 		v[1].a_un.a_str = "-d";
2259 		v[2].a_type = MDB_TYPE_IMMEDIATE;
2260 		v[2].a_un.a_val = 2;
2261 
2262 		len = sav->sav_count * sizeof (uintptr_t);
2263 		aux = mdb_alloc(len, UM_SLEEP);
2264 		if (mdb_vread(aux, len, sav->sav_vdevs) == -1) {
2265 			mdb_free(aux, len);
2266 			mdb_warn("failed to read l2cache vdevs at %p",
2267 			    sav->sav_vdevs);
2268 			return (DCMD_ERR);
2269 		}
2270 
2271 		mdb_printf("%-?s %-9s %-12s %s\n", "-", "-", "-", name);
2272 
2273 		for (i = 0; i < sav->sav_count; i++) {
2274 			ret = mdb_call_dcmd("vdev", aux[i], flags, 3, v);
2275 			if (ret != DCMD_OK) {
2276 				mdb_free(aux, len);
2277 				return (ret);
2278 			}
2279 		}
2280 
2281 		mdb_free(aux, len);
2282 	}
2283 
2284 	return (0);
2285 }
2286 
2287 /*
2288  * ::spa_vdevs
2289  *
2290  *	-e	Include error stats
2291  *	-m	Include metaslab information
2292  *	-M	Include metaslab group information
2293  *	-h	Include histogram information (requires -m or -M)
2294  *
2295  * Print out a summarized list of vdevs for the given spa_t.
2296  * This is accomplished by invoking "::vdev -re" on the root vdev, as well as
2297  * iterating over the cache devices.
2298  */
2299 /* ARGSUSED */
2300 static int
2301 spa_vdevs(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2302 {
2303 	mdb_arg_t v[3];
2304 	int ret;
2305 	char opts[100] = "-r";
2306 	int spa_flags = 0;
2307 
2308 	if (mdb_getopts(argc, argv,
2309 	    'e', MDB_OPT_SETBITS, SPA_FLAG_ERRORS, &spa_flags,
2310 	    'm', MDB_OPT_SETBITS, SPA_FLAG_METASLABS, &spa_flags,
2311 	    'M', MDB_OPT_SETBITS, SPA_FLAG_METASLAB_GROUPS, &spa_flags,
2312 	    'h', MDB_OPT_SETBITS, SPA_FLAG_HISTOGRAMS, &spa_flags,
2313 	    NULL) != argc)
2314 		return (DCMD_USAGE);
2315 
2316 	if (!(flags & DCMD_ADDRSPEC))
2317 		return (DCMD_USAGE);
2318 
2319 	mdb_spa_vdevs_t spa;
2320 	if (mdb_ctf_vread(&spa, "spa_t", "mdb_spa_vdevs_t", addr, 0) == -1)
2321 		return (DCMD_ERR);
2322 
2323 	/*
2324 	 * Unitialized spa_t structures can have a NULL root vdev.
2325 	 */
2326 	if (spa.spa_root_vdev == 0) {
2327 		mdb_printf("no associated vdevs\n");
2328 		return (DCMD_OK);
2329 	}
2330 
2331 	if (spa_flags & SPA_FLAG_ERRORS)
2332 		strcat(opts, "e");
2333 	if (spa_flags & SPA_FLAG_METASLABS)
2334 		strcat(opts, "m");
2335 	if (spa_flags & SPA_FLAG_METASLAB_GROUPS)
2336 		strcat(opts, "M");
2337 	if (spa_flags & SPA_FLAG_HISTOGRAMS)
2338 		strcat(opts, "h");
2339 
2340 	v[0].a_type = MDB_TYPE_STRING;
2341 	v[0].a_un.a_str = opts;
2342 
2343 	ret = mdb_call_dcmd("vdev", (uintptr_t)spa.spa_root_vdev,
2344 	    flags, 1, v);
2345 	if (ret != DCMD_OK)
2346 		return (ret);
2347 
2348 	if (spa_print_aux(&spa.spa_l2cache, flags, v, "cache") != 0 ||
2349 	    spa_print_aux(&spa.spa_spares, flags, v, "spares") != 0)
2350 		return (DCMD_ERR);
2351 
2352 	return (DCMD_OK);
2353 }
2354 
2355 /*
2356  * ::zio
2357  *
2358  * Print a summary of zio_t and all its children.  This is intended to display a
2359  * zio tree, and hence we only pick the most important pieces of information for
2360  * the main summary.  More detailed information can always be found by doing a
2361  * '::print zio' on the underlying zio_t.  The columns we display are:
2362  *
2363  *	ADDRESS  TYPE  STAGE  WAITER  TIME_ELAPSED
2364  *
2365  * The 'address' column is indented by one space for each depth level as we
2366  * descend down the tree.
2367  */
2368 
2369 #define	ZIO_MAXINDENT	7
2370 #define	ZIO_MAXWIDTH	(sizeof (uintptr_t) * 2 + ZIO_MAXINDENT)
2371 #define	ZIO_WALK_SELF	0
2372 #define	ZIO_WALK_CHILD	1
2373 #define	ZIO_WALK_PARENT	2
2374 
2375 typedef struct zio_print_args {
2376 	int	zpa_current_depth;
2377 	int	zpa_min_depth;
2378 	int	zpa_max_depth;
2379 	int	zpa_type;
2380 	uint_t	zpa_flags;
2381 } zio_print_args_t;
2382 
2383 typedef struct mdb_zio {
2384 	enum zio_type io_type;
2385 	enum zio_stage io_stage;
2386 	uintptr_t io_waiter;
2387 	uintptr_t io_spa;
2388 	struct {
2389 		struct {
2390 			uintptr_t list_next;
2391 		} list_head;
2392 	} io_parent_list;
2393 	int io_error;
2394 } mdb_zio_t;
2395 
2396 typedef struct mdb_zio_timestamp {
2397 	hrtime_t io_timestamp;
2398 } mdb_zio_timestamp_t;
2399 
2400 static int zio_child_cb(uintptr_t addr, const void *unknown, void *arg);
2401 
2402 static int
2403 zio_print_cb(uintptr_t addr, zio_print_args_t *zpa)
2404 {
2405 	mdb_ctf_id_t type_enum, stage_enum;
2406 	int indent = zpa->zpa_current_depth;
2407 	const char *type, *stage;
2408 	uintptr_t laddr;
2409 	mdb_zio_t zio;
2410 	mdb_zio_timestamp_t zio_timestamp = { 0 };
2411 
2412 	if (mdb_ctf_vread(&zio, ZFS_STRUCT "zio", "mdb_zio_t", addr, 0) == -1)
2413 		return (WALK_ERR);
2414 	(void) mdb_ctf_vread(&zio_timestamp, ZFS_STRUCT "zio",
2415 	    "mdb_zio_timestamp_t", addr, MDB_CTF_VREAD_QUIET);
2416 
2417 	if (indent > ZIO_MAXINDENT)
2418 		indent = ZIO_MAXINDENT;
2419 
2420 	if (mdb_ctf_lookup_by_name("enum zio_type", &type_enum) == -1 ||
2421 	    mdb_ctf_lookup_by_name("enum zio_stage", &stage_enum) == -1) {
2422 		mdb_warn("failed to lookup zio enums");
2423 		return (WALK_ERR);
2424 	}
2425 
2426 	if ((type = mdb_ctf_enum_name(type_enum, zio.io_type)) != NULL)
2427 		type += sizeof ("ZIO_TYPE_") - 1;
2428 	else
2429 		type = "?";
2430 
2431 	if (zio.io_error == 0) {
2432 		stage = mdb_ctf_enum_name(stage_enum, zio.io_stage);
2433 		if (stage != NULL)
2434 			stage += sizeof ("ZIO_STAGE_") - 1;
2435 		else
2436 			stage = "?";
2437 	} else {
2438 		stage = "FAILED";
2439 	}
2440 
2441 	if (zpa->zpa_current_depth >= zpa->zpa_min_depth) {
2442 		if (zpa->zpa_flags & DCMD_PIPE_OUT) {
2443 			mdb_printf("%?p\n", addr);
2444 		} else {
2445 			mdb_printf("%*s%-*p %-5s %-16s ", indent, "",
2446 			    ZIO_MAXWIDTH - indent, addr, type, stage);
2447 			if (zio.io_waiter != 0)
2448 				mdb_printf("%-16lx ", zio.io_waiter);
2449 			else
2450 				mdb_printf("%-16s ", "-");
2451 #ifdef _KERNEL
2452 			if (zio_timestamp.io_timestamp != 0) {
2453 				mdb_printf("%llums", (mdb_gethrtime() -
2454 				    zio_timestamp.io_timestamp) /
2455 				    1000000);
2456 			} else {
2457 				mdb_printf("%-12s ", "-");
2458 			}
2459 #else
2460 			mdb_printf("%-12s ", "-");
2461 #endif
2462 			mdb_printf("\n");
2463 		}
2464 	}
2465 
2466 	if (zpa->zpa_current_depth >= zpa->zpa_max_depth)
2467 		return (WALK_NEXT);
2468 
2469 	if (zpa->zpa_type == ZIO_WALK_PARENT)
2470 		laddr = addr + mdb_ctf_offsetof_by_name(ZFS_STRUCT "zio",
2471 		    "io_parent_list");
2472 	else
2473 		laddr = addr + mdb_ctf_offsetof_by_name(ZFS_STRUCT "zio",
2474 		    "io_child_list");
2475 
2476 	zpa->zpa_current_depth++;
2477 	if (mdb_pwalk("list", zio_child_cb, zpa, laddr) != 0) {
2478 		mdb_warn("failed to walk zio_t children at %p\n", laddr);
2479 		return (WALK_ERR);
2480 	}
2481 	zpa->zpa_current_depth--;
2482 
2483 	return (WALK_NEXT);
2484 }
2485 
2486 /* ARGSUSED */
2487 static int
2488 zio_child_cb(uintptr_t addr, const void *unknown, void *arg)
2489 {
2490 	zio_link_t zl;
2491 	uintptr_t ziop;
2492 	zio_print_args_t *zpa = arg;
2493 
2494 	if (mdb_vread(&zl, sizeof (zl), addr) == -1) {
2495 		mdb_warn("failed to read zio_link_t at %p", addr);
2496 		return (WALK_ERR);
2497 	}
2498 
2499 	if (zpa->zpa_type == ZIO_WALK_PARENT)
2500 		ziop = (uintptr_t)zl.zl_parent;
2501 	else
2502 		ziop = (uintptr_t)zl.zl_child;
2503 
2504 	return (zio_print_cb(ziop, zpa));
2505 }
2506 
2507 /* ARGSUSED */
2508 static int
2509 zio_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2510 {
2511 	zio_print_args_t zpa = { 0 };
2512 
2513 	if (!(flags & DCMD_ADDRSPEC))
2514 		return (DCMD_USAGE);
2515 
2516 	if (mdb_getopts(argc, argv,
2517 	    'r', MDB_OPT_SETBITS, INT_MAX, &zpa.zpa_max_depth,
2518 	    'c', MDB_OPT_SETBITS, ZIO_WALK_CHILD, &zpa.zpa_type,
2519 	    'p', MDB_OPT_SETBITS, ZIO_WALK_PARENT, &zpa.zpa_type,
2520 	    NULL) != argc)
2521 		return (DCMD_USAGE);
2522 
2523 	zpa.zpa_flags = flags;
2524 	if (zpa.zpa_max_depth != 0) {
2525 		if (zpa.zpa_type == ZIO_WALK_SELF)
2526 			zpa.zpa_type = ZIO_WALK_CHILD;
2527 	} else if (zpa.zpa_type != ZIO_WALK_SELF) {
2528 		zpa.zpa_min_depth = 1;
2529 		zpa.zpa_max_depth = 1;
2530 	}
2531 
2532 	if (!(flags & DCMD_PIPE_OUT) && DCMD_HDRSPEC(flags)) {
2533 		mdb_printf("%<u>%-*s %-5s %-16s %-16s %-12s%</u>\n",
2534 		    ZIO_MAXWIDTH, "ADDRESS", "TYPE", "STAGE", "WAITER",
2535 		    "TIME_ELAPSED");
2536 	}
2537 
2538 	if (zio_print_cb(addr, &zpa) != WALK_NEXT)
2539 		return (DCMD_ERR);
2540 
2541 	return (DCMD_OK);
2542 }
2543 
2544 /*
2545  * [addr]::zio_state
2546  *
2547  * Print a summary of all zio_t structures on the system, or for a particular
2548  * pool.  This is equivalent to '::walk zio_root | ::zio'.
2549  */
2550 /*ARGSUSED*/
2551 static int
2552 zio_state(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2553 {
2554 	/*
2555 	 * MDB will remember the last address of the pipeline, so if we don't
2556 	 * zero this we'll end up trying to walk zio structures for a
2557 	 * non-existent spa_t.
2558 	 */
2559 	if (!(flags & DCMD_ADDRSPEC))
2560 		addr = 0;
2561 
2562 	return (mdb_pwalk_dcmd("zio_root", "zio", argc, argv, addr));
2563 }
2564 
2565 typedef struct mdb_multilist {
2566 	uint64_t ml_num_sublists;
2567 	uintptr_t ml_sublists;
2568 } mdb_multilist_t;
2569 
2570 typedef struct multilist_walk_data {
2571 	uint64_t mwd_idx;
2572 	mdb_multilist_t mwd_ml;
2573 } multilist_walk_data_t;
2574 
2575 /* ARGSUSED */
2576 static int
2577 multilist_print_cb(uintptr_t addr, const void *unknown, void *arg)
2578 {
2579 	mdb_printf("%#lr\n", addr);
2580 	return (WALK_NEXT);
2581 }
2582 
2583 static int
2584 multilist_walk_step(mdb_walk_state_t *wsp)
2585 {
2586 	multilist_walk_data_t *mwd = wsp->walk_data;
2587 
2588 	if (mwd->mwd_idx >= mwd->mwd_ml.ml_num_sublists)
2589 		return (WALK_DONE);
2590 
2591 	wsp->walk_addr = mwd->mwd_ml.ml_sublists +
2592 	    mdb_ctf_sizeof_by_name("multilist_sublist_t") * mwd->mwd_idx +
2593 	    mdb_ctf_offsetof_by_name("multilist_sublist_t", "mls_list");
2594 
2595 	mdb_pwalk("list", multilist_print_cb, (void*)NULL, wsp->walk_addr);
2596 	mwd->mwd_idx++;
2597 
2598 	return (WALK_NEXT);
2599 }
2600 
2601 static int
2602 multilist_walk_init(mdb_walk_state_t *wsp)
2603 {
2604 	multilist_walk_data_t *mwd;
2605 
2606 	if (wsp->walk_addr == 0) {
2607 		mdb_warn("must supply address of multilist_t\n");
2608 		return (WALK_ERR);
2609 	}
2610 
2611 	mwd = mdb_zalloc(sizeof (multilist_walk_data_t), UM_SLEEP | UM_GC);
2612 	if (mdb_ctf_vread(&mwd->mwd_ml, "multilist_t", "mdb_multilist_t",
2613 	    wsp->walk_addr, 0) == -1) {
2614 		return (WALK_ERR);
2615 	}
2616 
2617 	if (mwd->mwd_ml.ml_num_sublists == 0 ||
2618 	    mwd->mwd_ml.ml_sublists == 0) {
2619 		mdb_warn("invalid or uninitialized multilist at %#lx\n",
2620 		    wsp->walk_addr);
2621 		return (WALK_ERR);
2622 	}
2623 
2624 	wsp->walk_data = mwd;
2625 	return (WALK_NEXT);
2626 }
2627 
2628 typedef struct mdb_txg_list {
2629 	size_t		tl_offset;
2630 	uintptr_t	tl_head[TXG_SIZE];
2631 } mdb_txg_list_t;
2632 
2633 typedef struct txg_list_walk_data {
2634 	uintptr_t lw_head[TXG_SIZE];
2635 	int	lw_txgoff;
2636 	int	lw_maxoff;
2637 	size_t	lw_offset;
2638 	void	*lw_obj;
2639 } txg_list_walk_data_t;
2640 
2641 static int
2642 txg_list_walk_init_common(mdb_walk_state_t *wsp, int txg, int maxoff)
2643 {
2644 	txg_list_walk_data_t *lwd;
2645 	mdb_txg_list_t list;
2646 	int i;
2647 
2648 	lwd = mdb_alloc(sizeof (txg_list_walk_data_t), UM_SLEEP | UM_GC);
2649 	if (mdb_ctf_vread(&list, "txg_list_t", "mdb_txg_list_t", wsp->walk_addr,
2650 	    0) == -1) {
2651 		mdb_warn("failed to read txg_list_t at %#lx", wsp->walk_addr);
2652 		return (WALK_ERR);
2653 	}
2654 
2655 	for (i = 0; i < TXG_SIZE; i++)
2656 		lwd->lw_head[i] = list.tl_head[i];
2657 	lwd->lw_offset = list.tl_offset;
2658 	lwd->lw_obj = mdb_alloc(lwd->lw_offset + sizeof (txg_node_t),
2659 	    UM_SLEEP | UM_GC);
2660 	lwd->lw_txgoff = txg;
2661 	lwd->lw_maxoff = maxoff;
2662 
2663 	wsp->walk_addr = lwd->lw_head[lwd->lw_txgoff];
2664 	wsp->walk_data = lwd;
2665 
2666 	return (WALK_NEXT);
2667 }
2668 
2669 static int
2670 txg_list_walk_init(mdb_walk_state_t *wsp)
2671 {
2672 	return (txg_list_walk_init_common(wsp, 0, TXG_SIZE-1));
2673 }
2674 
2675 static int
2676 txg_list0_walk_init(mdb_walk_state_t *wsp)
2677 {
2678 	return (txg_list_walk_init_common(wsp, 0, 0));
2679 }
2680 
2681 static int
2682 txg_list1_walk_init(mdb_walk_state_t *wsp)
2683 {
2684 	return (txg_list_walk_init_common(wsp, 1, 1));
2685 }
2686 
2687 static int
2688 txg_list2_walk_init(mdb_walk_state_t *wsp)
2689 {
2690 	return (txg_list_walk_init_common(wsp, 2, 2));
2691 }
2692 
2693 static int
2694 txg_list3_walk_init(mdb_walk_state_t *wsp)
2695 {
2696 	return (txg_list_walk_init_common(wsp, 3, 3));
2697 }
2698 
2699 static int
2700 txg_list_walk_step(mdb_walk_state_t *wsp)
2701 {
2702 	txg_list_walk_data_t *lwd = wsp->walk_data;
2703 	uintptr_t addr;
2704 	txg_node_t *node;
2705 	int status;
2706 
2707 	while (wsp->walk_addr == 0 && lwd->lw_txgoff < lwd->lw_maxoff) {
2708 		lwd->lw_txgoff++;
2709 		wsp->walk_addr = lwd->lw_head[lwd->lw_txgoff];
2710 	}
2711 
2712 	if (wsp->walk_addr == 0)
2713 		return (WALK_DONE);
2714 
2715 	addr = wsp->walk_addr - lwd->lw_offset;
2716 
2717 	if (mdb_vread(lwd->lw_obj,
2718 	    lwd->lw_offset + sizeof (txg_node_t), addr) == -1) {
2719 		mdb_warn("failed to read list element at %#lx", addr);
2720 		return (WALK_ERR);
2721 	}
2722 
2723 	status = wsp->walk_callback(addr, lwd->lw_obj, wsp->walk_cbdata);
2724 	node = (txg_node_t *)((uintptr_t)lwd->lw_obj + lwd->lw_offset);
2725 	wsp->walk_addr = (uintptr_t)node->tn_next[lwd->lw_txgoff];
2726 
2727 	return (status);
2728 }
2729 
2730 /*
2731  * ::walk spa
2732  *
2733  * Walk all named spa_t structures in the namespace.  This is nothing more than
2734  * a layered avl walk.
2735  */
2736 static int
2737 spa_walk_init(mdb_walk_state_t *wsp)
2738 {
2739 	GElf_Sym sym;
2740 
2741 	if (wsp->walk_addr != 0) {
2742 		mdb_warn("spa walk only supports global walks\n");
2743 		return (WALK_ERR);
2744 	}
2745 
2746 	if (mdb_lookup_by_obj(ZFS_OBJ_NAME, "spa_namespace_avl", &sym) == -1) {
2747 		mdb_warn("failed to find symbol 'spa_namespace_avl'");
2748 		return (WALK_ERR);
2749 	}
2750 
2751 	wsp->walk_addr = (uintptr_t)sym.st_value;
2752 
2753 	if (mdb_layered_walk("avl", wsp) == -1) {
2754 		mdb_warn("failed to walk 'avl'\n");
2755 		return (WALK_ERR);
2756 	}
2757 
2758 	return (WALK_NEXT);
2759 }
2760 
2761 static int
2762 spa_walk_step(mdb_walk_state_t *wsp)
2763 {
2764 	return (wsp->walk_callback(wsp->walk_addr, NULL, wsp->walk_cbdata));
2765 }
2766 
2767 /*
2768  * [addr]::walk zio
2769  *
2770  * Walk all active zio_t structures on the system.  This is simply a layered
2771  * walk on top of ::walk zio_cache, with the optional ability to limit the
2772  * structures to a particular pool.
2773  */
2774 static int
2775 zio_walk_init(mdb_walk_state_t *wsp)
2776 {
2777 	wsp->walk_data = (void *)wsp->walk_addr;
2778 
2779 	if (mdb_layered_walk("zio_cache", wsp) == -1) {
2780 		mdb_warn("failed to walk 'zio_cache'\n");
2781 		return (WALK_ERR);
2782 	}
2783 
2784 	return (WALK_NEXT);
2785 }
2786 
2787 static int
2788 zio_walk_step(mdb_walk_state_t *wsp)
2789 {
2790 	mdb_zio_t zio;
2791 	uintptr_t spa = (uintptr_t)wsp->walk_data;
2792 
2793 	if (mdb_ctf_vread(&zio, ZFS_STRUCT "zio", "mdb_zio_t",
2794 	    wsp->walk_addr, 0) == -1)
2795 		return (WALK_ERR);
2796 
2797 	if (spa != 0 && spa != zio.io_spa)
2798 		return (WALK_NEXT);
2799 
2800 	return (wsp->walk_callback(wsp->walk_addr, &zio, wsp->walk_cbdata));
2801 }
2802 
2803 /*
2804  * [addr]::walk zio_root
2805  *
2806  * Walk only root zio_t structures, optionally for a particular spa_t.
2807  */
2808 static int
2809 zio_walk_root_step(mdb_walk_state_t *wsp)
2810 {
2811 	mdb_zio_t zio;
2812 	uintptr_t spa = (uintptr_t)wsp->walk_data;
2813 
2814 	if (mdb_ctf_vread(&zio, ZFS_STRUCT "zio", "mdb_zio_t",
2815 	    wsp->walk_addr, 0) == -1)
2816 		return (WALK_ERR);
2817 
2818 	if (spa != 0 && spa != zio.io_spa)
2819 		return (WALK_NEXT);
2820 
2821 	/* If the parent list is not empty, ignore */
2822 	if (zio.io_parent_list.list_head.list_next !=
2823 	    wsp->walk_addr +
2824 	    mdb_ctf_offsetof_by_name(ZFS_STRUCT "zio", "io_parent_list") +
2825 	    mdb_ctf_offsetof_by_name("struct list", "list_head"))
2826 		return (WALK_NEXT);
2827 
2828 	return (wsp->walk_callback(wsp->walk_addr, &zio, wsp->walk_cbdata));
2829 }
2830 
2831 /*
2832  * ::zfs_blkstats
2833  *
2834  *	-v	print verbose per-level information
2835  *
2836  */
2837 static int
2838 zfs_blkstats(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2839 {
2840 	boolean_t verbose = B_FALSE;
2841 	zfs_all_blkstats_t stats;
2842 	dmu_object_type_t t;
2843 	zfs_blkstat_t *tzb;
2844 	uint64_t ditto;
2845 	dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES + 10];
2846 	/* +10 in case it grew */
2847 
2848 	if (mdb_readvar(&dmu_ot, "dmu_ot") == -1) {
2849 		mdb_warn("failed to read 'dmu_ot'");
2850 		return (DCMD_ERR);
2851 	}
2852 
2853 	if (mdb_getopts(argc, argv,
2854 	    'v', MDB_OPT_SETBITS, TRUE, &verbose,
2855 	    NULL) != argc)
2856 		return (DCMD_USAGE);
2857 
2858 	if (!(flags & DCMD_ADDRSPEC))
2859 		return (DCMD_USAGE);
2860 
2861 	if (GETMEMB(addr, "spa", spa_dsl_pool, addr) ||
2862 	    GETMEMB(addr, "dsl_pool", dp_blkstats, addr) ||
2863 	    mdb_vread(&stats, sizeof (zfs_all_blkstats_t), addr) == -1) {
2864 		mdb_warn("failed to read data at %p;", addr);
2865 		mdb_printf("maybe no stats? run \"zpool scrub\" first.");
2866 		return (DCMD_ERR);
2867 	}
2868 
2869 	tzb = &stats.zab_type[DN_MAX_LEVELS][DMU_OT_TOTAL];
2870 	if (tzb->zb_gangs != 0) {
2871 		mdb_printf("Ganged blocks: %llu\n",
2872 		    (longlong_t)tzb->zb_gangs);
2873 	}
2874 
2875 	ditto = tzb->zb_ditto_2_of_2_samevdev + tzb->zb_ditto_2_of_3_samevdev +
2876 	    tzb->zb_ditto_3_of_3_samevdev;
2877 	if (ditto != 0) {
2878 		mdb_printf("Dittoed blocks on same vdev: %llu\n",
2879 		    (longlong_t)ditto);
2880 	}
2881 
2882 	mdb_printf("\nBlocks\tLSIZE\tPSIZE\tASIZE"
2883 	    "\t  avg\t comp\t%%Total\tType\n");
2884 
2885 	for (t = 0; t <= DMU_OT_TOTAL; t++) {
2886 		char csize[MDB_NICENUM_BUFLEN], lsize[MDB_NICENUM_BUFLEN];
2887 		char psize[MDB_NICENUM_BUFLEN], asize[MDB_NICENUM_BUFLEN];
2888 		char avg[MDB_NICENUM_BUFLEN];
2889 		char comp[MDB_NICENUM_BUFLEN], pct[MDB_NICENUM_BUFLEN];
2890 		char typename[64];
2891 		int l;
2892 
2893 
2894 		if (t == DMU_OT_DEFERRED)
2895 			strcpy(typename, "deferred free");
2896 		else if (t == DMU_OT_OTHER)
2897 			strcpy(typename, "other");
2898 		else if (t == DMU_OT_TOTAL)
2899 			strcpy(typename, "Total");
2900 		else if (mdb_readstr(typename, sizeof (typename),
2901 		    (uintptr_t)dmu_ot[t].ot_name) == -1) {
2902 			mdb_warn("failed to read type name");
2903 			return (DCMD_ERR);
2904 		}
2905 
2906 		if (stats.zab_type[DN_MAX_LEVELS][t].zb_asize == 0)
2907 			continue;
2908 
2909 		for (l = -1; l < DN_MAX_LEVELS; l++) {
2910 			int level = (l == -1 ? DN_MAX_LEVELS : l);
2911 			zfs_blkstat_t *zb = &stats.zab_type[level][t];
2912 
2913 			if (zb->zb_asize == 0)
2914 				continue;
2915 
2916 			/*
2917 			 * Don't print each level unless requested.
2918 			 */
2919 			if (!verbose && level != DN_MAX_LEVELS)
2920 				continue;
2921 
2922 			/*
2923 			 * If all the space is level 0, don't print the
2924 			 * level 0 separately.
2925 			 */
2926 			if (level == 0 && zb->zb_asize ==
2927 			    stats.zab_type[DN_MAX_LEVELS][t].zb_asize)
2928 				continue;
2929 
2930 			mdb_nicenum(zb->zb_count, csize);
2931 			mdb_nicenum(zb->zb_lsize, lsize);
2932 			mdb_nicenum(zb->zb_psize, psize);
2933 			mdb_nicenum(zb->zb_asize, asize);
2934 			mdb_nicenum(zb->zb_asize / zb->zb_count, avg);
2935 			(void) mdb_snprintfrac(comp, MDB_NICENUM_BUFLEN,
2936 			    zb->zb_lsize, zb->zb_psize, 2);
2937 			(void) mdb_snprintfrac(pct, MDB_NICENUM_BUFLEN,
2938 			    100 * zb->zb_asize, tzb->zb_asize, 2);
2939 
2940 			mdb_printf("%6s\t%5s\t%5s\t%5s\t%5s"
2941 			    "\t%5s\t%6s\t",
2942 			    csize, lsize, psize, asize, avg, comp, pct);
2943 
2944 			if (level == DN_MAX_LEVELS)
2945 				mdb_printf("%s\n", typename);
2946 			else
2947 				mdb_printf("  L%d %s\n",
2948 				    level, typename);
2949 		}
2950 	}
2951 
2952 	return (DCMD_OK);
2953 }
2954 
2955 typedef struct mdb_reference {
2956 	uintptr_t ref_holder;
2957 	uintptr_t ref_removed;
2958 	uint64_t ref_number;
2959 } mdb_reference_t;
2960 
2961 /* ARGSUSED */
2962 static int
2963 reference_cb(uintptr_t addr, const void *ignored, void *arg)
2964 {
2965 	mdb_reference_t ref;
2966 	boolean_t holder_is_str = B_FALSE;
2967 	char holder_str[128];
2968 	boolean_t removed = (boolean_t)arg;
2969 
2970 	if (mdb_ctf_vread(&ref, "reference_t", "mdb_reference_t", addr,
2971 	    0) == -1)
2972 		return (DCMD_ERR);
2973 
2974 	if (mdb_readstr(holder_str, sizeof (holder_str),
2975 	    ref.ref_holder) != -1)
2976 		holder_is_str = strisprint(holder_str);
2977 
2978 	if (removed)
2979 		mdb_printf("removed ");
2980 	mdb_printf("reference ");
2981 	if (ref.ref_number != 1)
2982 		mdb_printf("with count=%llu ", ref.ref_number);
2983 	mdb_printf("with tag %lx", ref.ref_holder);
2984 	if (holder_is_str)
2985 		mdb_printf(" \"%s\"", holder_str);
2986 	mdb_printf(", held at:\n");
2987 
2988 	(void) mdb_call_dcmd("whatis", addr, DCMD_ADDRSPEC, 0, NULL);
2989 
2990 	if (removed) {
2991 		mdb_printf("removed at:\n");
2992 		(void) mdb_call_dcmd("whatis", ref.ref_removed,
2993 		    DCMD_ADDRSPEC, 0, NULL);
2994 	}
2995 
2996 	mdb_printf("\n");
2997 
2998 	return (WALK_NEXT);
2999 }
3000 
3001 typedef struct mdb_refcount {
3002 	uint64_t rc_count;
3003 } mdb_refcount_t;
3004 
3005 typedef struct mdb_refcount_removed {
3006 	uint64_t rc_removed_count;
3007 } mdb_refcount_removed_t;
3008 
3009 typedef struct mdb_refcount_tracked {
3010 	boolean_t rc_tracked;
3011 } mdb_refcount_tracked_t;
3012 
3013 /* ARGSUSED */
3014 static int
3015 refcount(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
3016 {
3017 	mdb_refcount_t rc;
3018 	mdb_refcount_removed_t rcr;
3019 	mdb_refcount_tracked_t rct;
3020 	int off;
3021 	boolean_t released = B_FALSE;
3022 
3023 	if (!(flags & DCMD_ADDRSPEC))
3024 		return (DCMD_USAGE);
3025 
3026 	if (mdb_getopts(argc, argv,
3027 	    'r', MDB_OPT_SETBITS, B_TRUE, &released,
3028 	    NULL) != argc)
3029 		return (DCMD_USAGE);
3030 
3031 	if (mdb_ctf_vread(&rc, "refcount_t", "mdb_refcount_t", addr,
3032 	    0) == -1)
3033 		return (DCMD_ERR);
3034 
3035 	if (mdb_ctf_vread(&rcr, "refcount_t", "mdb_refcount_removed_t", addr,
3036 	    MDB_CTF_VREAD_QUIET) == -1) {
3037 		mdb_printf("refcount_t at %p has %llu holds (untracked)\n",
3038 		    addr, (longlong_t)rc.rc_count);
3039 		return (DCMD_OK);
3040 	}
3041 
3042 	if (mdb_ctf_vread(&rct, "refcount_t", "mdb_refcount_tracked_t", addr,
3043 	    MDB_CTF_VREAD_QUIET) == -1) {
3044 		/* If this is an old target, it might be tracked. */
3045 		rct.rc_tracked = B_TRUE;
3046 	}
3047 
3048 	mdb_printf("refcount_t at %p has %llu current holds, "
3049 	    "%llu recently released holds\n",
3050 	    addr, (longlong_t)rc.rc_count, (longlong_t)rcr.rc_removed_count);
3051 
3052 	if (rct.rc_tracked && rc.rc_count > 0)
3053 		mdb_printf("current holds:\n");
3054 	off = mdb_ctf_offsetof_by_name("refcount_t", "rc_list");
3055 	if (off == -1)
3056 		return (DCMD_ERR);
3057 	mdb_pwalk("list", reference_cb, (void*)B_FALSE, addr + off);
3058 
3059 	if (released && rcr.rc_removed_count > 0) {
3060 		mdb_printf("released holds:\n");
3061 
3062 		off = mdb_ctf_offsetof_by_name("refcount_t", "rc_removed");
3063 		if (off == -1)
3064 			return (DCMD_ERR);
3065 		mdb_pwalk("list", reference_cb, (void*)B_TRUE, addr + off);
3066 	}
3067 
3068 	return (DCMD_OK);
3069 }
3070 
3071 /* ARGSUSED */
3072 static int
3073 sa_attr_table(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
3074 {
3075 	sa_attr_table_t *table;
3076 	sa_os_t sa_os;
3077 	char *name;
3078 	int i;
3079 
3080 	if (mdb_vread(&sa_os, sizeof (sa_os_t), addr) == -1) {
3081 		mdb_warn("failed to read sa_os at %p", addr);
3082 		return (DCMD_ERR);
3083 	}
3084 
3085 	table = mdb_alloc(sizeof (sa_attr_table_t) * sa_os.sa_num_attrs,
3086 	    UM_SLEEP | UM_GC);
3087 	name = mdb_alloc(MAXPATHLEN, UM_SLEEP | UM_GC);
3088 
3089 	if (mdb_vread(table, sizeof (sa_attr_table_t) * sa_os.sa_num_attrs,
3090 	    (uintptr_t)sa_os.sa_attr_table) == -1) {
3091 		mdb_warn("failed to read sa_os at %p", addr);
3092 		return (DCMD_ERR);
3093 	}
3094 
3095 	mdb_printf("%<u>%-10s %-10s %-10s %-10s %s%</u>\n",
3096 	    "ATTR ID", "REGISTERED", "LENGTH", "BSWAP", "NAME");
3097 	for (i = 0; i != sa_os.sa_num_attrs; i++) {
3098 		mdb_readstr(name, MAXPATHLEN, (uintptr_t)table[i].sa_name);
3099 		mdb_printf("%5x   %8x %8x %8x          %-s\n",
3100 		    (int)table[i].sa_attr, (int)table[i].sa_registered,
3101 		    (int)table[i].sa_length, table[i].sa_byteswap, name);
3102 	}
3103 
3104 	return (DCMD_OK);
3105 }
3106 
3107 static int
3108 sa_get_off_table(uintptr_t addr, uint32_t **off_tab, int attr_count)
3109 {
3110 	uintptr_t idx_table;
3111 
3112 	if (GETMEMB(addr, "sa_idx_tab", sa_idx_tab, idx_table)) {
3113 		mdb_printf("can't find offset table in sa_idx_tab\n");
3114 		return (-1);
3115 	}
3116 
3117 	*off_tab = mdb_alloc(attr_count * sizeof (uint32_t),
3118 	    UM_SLEEP | UM_GC);
3119 
3120 	if (mdb_vread(*off_tab,
3121 	    attr_count * sizeof (uint32_t), idx_table) == -1) {
3122 		mdb_warn("failed to attribute offset table %p", idx_table);
3123 		return (-1);
3124 	}
3125 
3126 	return (DCMD_OK);
3127 }
3128 
3129 /*ARGSUSED*/
3130 static int
3131 sa_attr_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
3132 {
3133 	uint32_t *offset_tab;
3134 	int attr_count;
3135 	uint64_t attr_id;
3136 	uintptr_t attr_addr;
3137 	uintptr_t bonus_tab, spill_tab;
3138 	uintptr_t db_bonus, db_spill;
3139 	uintptr_t os, os_sa;
3140 	uintptr_t db_data;
3141 
3142 	if (argc != 1)
3143 		return (DCMD_USAGE);
3144 
3145 	if (argv[0].a_type == MDB_TYPE_STRING)
3146 		attr_id = mdb_strtoull(argv[0].a_un.a_str);
3147 	else
3148 		return (DCMD_USAGE);
3149 
3150 	if (GETMEMB(addr, "sa_handle", sa_bonus_tab, bonus_tab) ||
3151 	    GETMEMB(addr, "sa_handle", sa_spill_tab, spill_tab) ||
3152 	    GETMEMB(addr, "sa_handle", sa_os, os) ||
3153 	    GETMEMB(addr, "sa_handle", sa_bonus, db_bonus) ||
3154 	    GETMEMB(addr, "sa_handle", sa_spill, db_spill)) {
3155 		mdb_printf("Can't find necessary information in sa_handle "
3156 		    "in sa_handle\n");
3157 		return (DCMD_ERR);
3158 	}
3159 
3160 	if (GETMEMB(os, "objset", os_sa, os_sa)) {
3161 		mdb_printf("Can't find os_sa in objset\n");
3162 		return (DCMD_ERR);
3163 	}
3164 
3165 	if (GETMEMB(os_sa, "sa_os", sa_num_attrs, attr_count)) {
3166 		mdb_printf("Can't find sa_num_attrs\n");
3167 		return (DCMD_ERR);
3168 	}
3169 
3170 	if (attr_id > attr_count) {
3171 		mdb_printf("attribute id number is out of range\n");
3172 		return (DCMD_ERR);
3173 	}
3174 
3175 	if (bonus_tab) {
3176 		if (sa_get_off_table(bonus_tab, &offset_tab,
3177 		    attr_count) == -1) {
3178 			return (DCMD_ERR);
3179 		}
3180 
3181 		if (GETMEMB(db_bonus, "dmu_buf", db_data, db_data)) {
3182 			mdb_printf("can't find db_data in bonus dbuf\n");
3183 			return (DCMD_ERR);
3184 		}
3185 	}
3186 
3187 	if (bonus_tab && !TOC_ATTR_PRESENT(offset_tab[attr_id]) &&
3188 	    spill_tab == 0) {
3189 		mdb_printf("Attribute does not exist\n");
3190 		return (DCMD_ERR);
3191 	} else if (!TOC_ATTR_PRESENT(offset_tab[attr_id]) && spill_tab) {
3192 		if (sa_get_off_table(spill_tab, &offset_tab,
3193 		    attr_count) == -1) {
3194 			return (DCMD_ERR);
3195 		}
3196 		if (GETMEMB(db_spill, "dmu_buf", db_data, db_data)) {
3197 			mdb_printf("can't find db_data in spill dbuf\n");
3198 			return (DCMD_ERR);
3199 		}
3200 		if (!TOC_ATTR_PRESENT(offset_tab[attr_id])) {
3201 			mdb_printf("Attribute does not exist\n");
3202 			return (DCMD_ERR);
3203 		}
3204 	}
3205 	attr_addr = db_data + TOC_OFF(offset_tab[attr_id]);
3206 	mdb_printf("%p\n", attr_addr);
3207 	return (DCMD_OK);
3208 }
3209 
3210 /* ARGSUSED */
3211 static int
3212 zfs_ace_print_common(uintptr_t addr, uint_t flags,
3213     uint64_t id, uint32_t access_mask, uint16_t ace_flags,
3214     uint16_t ace_type, int verbose)
3215 {
3216 	if (DCMD_HDRSPEC(flags) && !verbose)
3217 		mdb_printf("%<u>%-?s %-8s %-8s %-8s %s%</u>\n",
3218 		    "ADDR", "FLAGS", "MASK", "TYPE", "ID");
3219 
3220 	if (!verbose) {
3221 		mdb_printf("%0?p %-8x %-8x %-8x %-llx\n", addr,
3222 		    ace_flags, access_mask, ace_type, id);
3223 		return (DCMD_OK);
3224 	}
3225 
3226 	switch (ace_flags & ACE_TYPE_FLAGS) {
3227 	case ACE_OWNER:
3228 		mdb_printf("owner@:");
3229 		break;
3230 	case (ACE_IDENTIFIER_GROUP | ACE_GROUP):
3231 		mdb_printf("group@:");
3232 		break;
3233 	case ACE_EVERYONE:
3234 		mdb_printf("everyone@:");
3235 		break;
3236 	case ACE_IDENTIFIER_GROUP:
3237 		mdb_printf("group:%llx:", (u_longlong_t)id);
3238 		break;
3239 	case 0: /* User entry */
3240 		mdb_printf("user:%llx:", (u_longlong_t)id);
3241 		break;
3242 	}
3243 
3244 	/* print out permission mask */
3245 	if (access_mask & ACE_READ_DATA)
3246 		mdb_printf("r");
3247 	else
3248 		mdb_printf("-");
3249 	if (access_mask & ACE_WRITE_DATA)
3250 		mdb_printf("w");
3251 	else
3252 		mdb_printf("-");
3253 	if (access_mask & ACE_EXECUTE)
3254 		mdb_printf("x");
3255 	else
3256 		mdb_printf("-");
3257 	if (access_mask & ACE_APPEND_DATA)
3258 		mdb_printf("p");
3259 	else
3260 		mdb_printf("-");
3261 	if (access_mask & ACE_DELETE)
3262 		mdb_printf("d");
3263 	else
3264 		mdb_printf("-");
3265 	if (access_mask & ACE_DELETE_CHILD)
3266 		mdb_printf("D");
3267 	else
3268 		mdb_printf("-");
3269 	if (access_mask & ACE_READ_ATTRIBUTES)
3270 		mdb_printf("a");
3271 	else
3272 		mdb_printf("-");
3273 	if (access_mask & ACE_WRITE_ATTRIBUTES)
3274 		mdb_printf("A");
3275 	else
3276 		mdb_printf("-");
3277 	if (access_mask & ACE_READ_NAMED_ATTRS)
3278 		mdb_printf("R");
3279 	else
3280 		mdb_printf("-");
3281 	if (access_mask & ACE_WRITE_NAMED_ATTRS)
3282 		mdb_printf("W");
3283 	else
3284 		mdb_printf("-");
3285 	if (access_mask & ACE_READ_ACL)
3286 		mdb_printf("c");
3287 	else
3288 		mdb_printf("-");
3289 	if (access_mask & ACE_WRITE_ACL)
3290 		mdb_printf("C");
3291 	else
3292 		mdb_printf("-");
3293 	if (access_mask & ACE_WRITE_OWNER)
3294 		mdb_printf("o");
3295 	else
3296 		mdb_printf("-");
3297 	if (access_mask & ACE_SYNCHRONIZE)
3298 		mdb_printf("s");
3299 	else
3300 		mdb_printf("-");
3301 
3302 	mdb_printf(":");
3303 
3304 	/* Print out inheritance flags */
3305 	if (ace_flags & ACE_FILE_INHERIT_ACE)
3306 		mdb_printf("f");
3307 	else
3308 		mdb_printf("-");
3309 	if (ace_flags & ACE_DIRECTORY_INHERIT_ACE)
3310 		mdb_printf("d");
3311 	else
3312 		mdb_printf("-");
3313 	if (ace_flags & ACE_INHERIT_ONLY_ACE)
3314 		mdb_printf("i");
3315 	else
3316 		mdb_printf("-");
3317 	if (ace_flags & ACE_NO_PROPAGATE_INHERIT_ACE)
3318 		mdb_printf("n");
3319 	else
3320 		mdb_printf("-");
3321 	if (ace_flags & ACE_SUCCESSFUL_ACCESS_ACE_FLAG)
3322 		mdb_printf("S");
3323 	else
3324 		mdb_printf("-");
3325 	if (ace_flags & ACE_FAILED_ACCESS_ACE_FLAG)
3326 		mdb_printf("F");
3327 	else
3328 		mdb_printf("-");
3329 	if (ace_flags & ACE_INHERITED_ACE)
3330 		mdb_printf("I");
3331 	else
3332 		mdb_printf("-");
3333 
3334 	switch (ace_type) {
3335 	case ACE_ACCESS_ALLOWED_ACE_TYPE:
3336 		mdb_printf(":allow\n");
3337 		break;
3338 	case ACE_ACCESS_DENIED_ACE_TYPE:
3339 		mdb_printf(":deny\n");
3340 		break;
3341 	case ACE_SYSTEM_AUDIT_ACE_TYPE:
3342 		mdb_printf(":audit\n");
3343 		break;
3344 	case ACE_SYSTEM_ALARM_ACE_TYPE:
3345 		mdb_printf(":alarm\n");
3346 		break;
3347 	default:
3348 		mdb_printf(":?\n");
3349 	}
3350 	return (DCMD_OK);
3351 }
3352 
3353 /* ARGSUSED */
3354 static int
3355 zfs_ace_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
3356 {
3357 	zfs_ace_t zace;
3358 	int verbose = FALSE;
3359 	uint64_t id;
3360 
3361 	if (!(flags & DCMD_ADDRSPEC))
3362 		return (DCMD_USAGE);
3363 
3364 	if (mdb_getopts(argc, argv,
3365 	    'v', MDB_OPT_SETBITS, TRUE, &verbose, TRUE, NULL) != argc)
3366 		return (DCMD_USAGE);
3367 
3368 	if (mdb_vread(&zace, sizeof (zfs_ace_t), addr) == -1) {
3369 		mdb_warn("failed to read zfs_ace_t");
3370 		return (DCMD_ERR);
3371 	}
3372 
3373 	if ((zace.z_hdr.z_flags & ACE_TYPE_FLAGS) == 0 ||
3374 	    (zace.z_hdr.z_flags & ACE_TYPE_FLAGS) == ACE_IDENTIFIER_GROUP)
3375 		id = zace.z_fuid;
3376 	else
3377 		id = -1;
3378 
3379 	return (zfs_ace_print_common(addr, flags, id, zace.z_hdr.z_access_mask,
3380 	    zace.z_hdr.z_flags, zace.z_hdr.z_type, verbose));
3381 }
3382 
3383 /* ARGSUSED */
3384 static int
3385 zfs_ace0_print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
3386 {
3387 	ace_t ace;
3388 	uint64_t id;
3389 	int verbose = FALSE;
3390 
3391 	if (!(flags & DCMD_ADDRSPEC))
3392 		return (DCMD_USAGE);
3393 
3394 	if (mdb_getopts(argc, argv,
3395 	    'v', MDB_OPT_SETBITS, TRUE, &verbose, TRUE, NULL) != argc)
3396 		return (DCMD_USAGE);
3397 
3398 	if (mdb_vread(&ace, sizeof (ace_t), addr) == -1) {
3399 		mdb_warn("failed to read ace_t");
3400 		return (DCMD_ERR);
3401 	}
3402 
3403 	if ((ace.a_flags & ACE_TYPE_FLAGS) == 0 ||
3404 	    (ace.a_flags & ACE_TYPE_FLAGS) == ACE_IDENTIFIER_GROUP)
3405 		id = ace.a_who;
3406 	else
3407 		id = -1;
3408 
3409 	return (zfs_ace_print_common(addr, flags, id, ace.a_access_mask,
3410 	    ace.a_flags, ace.a_type, verbose));
3411 }
3412 
3413 typedef struct acl_dump_args {
3414 	int a_argc;
3415 	const mdb_arg_t *a_argv;
3416 	uint16_t a_version;
3417 	int a_flags;
3418 } acl_dump_args_t;
3419 
3420 /* ARGSUSED */
3421 static int
3422 acl_aces_cb(uintptr_t addr, const void *unknown, void *arg)
3423 {
3424 	acl_dump_args_t *acl_args = (acl_dump_args_t *)arg;
3425 
3426 	if (acl_args->a_version == 1) {
3427 		if (mdb_call_dcmd("zfs_ace", addr,
3428 		    DCMD_ADDRSPEC|acl_args->a_flags, acl_args->a_argc,
3429 		    acl_args->a_argv) != DCMD_OK) {
3430 			return (WALK_ERR);
3431 		}
3432 	} else {
3433 		if (mdb_call_dcmd("zfs_ace0", addr,
3434 		    DCMD_ADDRSPEC|acl_args->a_flags, acl_args->a_argc,
3435 		    acl_args->a_argv) != DCMD_OK) {
3436 			return (WALK_ERR);
3437 		}
3438 	}
3439 	acl_args->a_flags = DCMD_LOOP;
3440 	return (WALK_NEXT);
3441 }
3442 
3443 /* ARGSUSED */
3444 static int
3445 acl_cb(uintptr_t addr, const void *unknown, void *arg)
3446 {
3447 	acl_dump_args_t *acl_args = (acl_dump_args_t *)arg;
3448 
3449 	if (acl_args->a_version == 1) {
3450 		if (mdb_pwalk("zfs_acl_node_aces", acl_aces_cb,
3451 		    arg, addr) != 0) {
3452 			mdb_warn("can't walk ACEs");
3453 			return (DCMD_ERR);
3454 		}
3455 	} else {
3456 		if (mdb_pwalk("zfs_acl_node_aces0", acl_aces_cb,
3457 		    arg, addr) != 0) {
3458 			mdb_warn("can't walk ACEs");
3459 			return (DCMD_ERR);
3460 		}
3461 	}
3462 	return (WALK_NEXT);
3463 }
3464 
3465 /* ARGSUSED */
3466 static int
3467 zfs_acl_dump(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
3468 {
3469 	zfs_acl_t zacl;
3470 	int verbose = FALSE;
3471 	acl_dump_args_t acl_args;
3472 
3473 	if (!(flags & DCMD_ADDRSPEC))
3474 		return (DCMD_USAGE);
3475 
3476 	if (mdb_getopts(argc, argv,
3477 	    'v', MDB_OPT_SETBITS, TRUE, &verbose, TRUE, NULL) != argc)
3478 		return (DCMD_USAGE);
3479 
3480 	if (mdb_vread(&zacl, sizeof (zfs_acl_t), addr) == -1) {
3481 		mdb_warn("failed to read zfs_acl_t");
3482 		return (DCMD_ERR);
3483 	}
3484 
3485 	acl_args.a_argc = argc;
3486 	acl_args.a_argv = argv;
3487 	acl_args.a_version = zacl.z_version;
3488 	acl_args.a_flags = DCMD_LOOPFIRST;
3489 
3490 	if (mdb_pwalk("zfs_acl_node", acl_cb, &acl_args, addr) != 0) {
3491 		mdb_warn("can't walk ACL");
3492 		return (DCMD_ERR);
3493 	}
3494 
3495 	return (DCMD_OK);
3496 }
3497 
3498 /* ARGSUSED */
3499 static int
3500 zfs_acl_node_walk_init(mdb_walk_state_t *wsp)
3501 {
3502 	if (wsp->walk_addr == 0) {
3503 		mdb_warn("must supply address of zfs_acl_node_t\n");
3504 		return (WALK_ERR);
3505 	}
3506 
3507 	wsp->walk_addr +=
3508 	    mdb_ctf_offsetof_by_name(ZFS_STRUCT "zfs_acl", "z_acl");
3509 
3510 	if (mdb_layered_walk("list", wsp) == -1) {
3511 		mdb_warn("failed to walk 'list'\n");
3512 		return (WALK_ERR);
3513 	}
3514 
3515 	return (WALK_NEXT);
3516 }
3517 
3518 static int
3519 zfs_acl_node_walk_step(mdb_walk_state_t *wsp)
3520 {
3521 	zfs_acl_node_t	aclnode;
3522 
3523 	if (mdb_vread(&aclnode, sizeof (zfs_acl_node_t),
3524 	    wsp->walk_addr) == -1) {
3525 		mdb_warn("failed to read zfs_acl_node at %p", wsp->walk_addr);
3526 		return (WALK_ERR);
3527 	}
3528 
3529 	return (wsp->walk_callback(wsp->walk_addr, &aclnode, wsp->walk_cbdata));
3530 }
3531 
3532 typedef struct ace_walk_data {
3533 	int		ace_count;
3534 	int		ace_version;
3535 } ace_walk_data_t;
3536 
3537 static int
3538 zfs_aces_walk_init_common(mdb_walk_state_t *wsp, int version,
3539     int ace_count, uintptr_t ace_data)
3540 {
3541 	ace_walk_data_t *ace_walk_data;
3542 
3543 	if (wsp->walk_addr == 0) {
3544 		mdb_warn("must supply address of zfs_acl_node_t\n");
3545 		return (WALK_ERR);
3546 	}
3547 
3548 	ace_walk_data = mdb_alloc(sizeof (ace_walk_data_t), UM_SLEEP | UM_GC);
3549 
3550 	ace_walk_data->ace_count = ace_count;
3551 	ace_walk_data->ace_version = version;
3552 
3553 	wsp->walk_addr = ace_data;
3554 	wsp->walk_data = ace_walk_data;
3555 
3556 	return (WALK_NEXT);
3557 }
3558 
3559 static int
3560 zfs_acl_node_aces_walk_init_common(mdb_walk_state_t *wsp, int version)
3561 {
3562 	static int gotid;
3563 	static mdb_ctf_id_t acl_id;
3564 	int z_ace_count;
3565 	uintptr_t z_acldata;
3566 
3567 	if (!gotid) {
3568 		if (mdb_ctf_lookup_by_name("struct zfs_acl_node",
3569 		    &acl_id) == -1) {
3570 			mdb_warn("couldn't find struct zfs_acl_node");
3571 			return (DCMD_ERR);
3572 		}
3573 		gotid = TRUE;
3574 	}
3575 
3576 	if (GETMEMBID(wsp->walk_addr, &acl_id, z_ace_count, z_ace_count)) {
3577 		return (DCMD_ERR);
3578 	}
3579 	if (GETMEMBID(wsp->walk_addr, &acl_id, z_acldata, z_acldata)) {
3580 		return (DCMD_ERR);
3581 	}
3582 
3583 	return (zfs_aces_walk_init_common(wsp, version,
3584 	    z_ace_count, z_acldata));
3585 }
3586 
3587 /* ARGSUSED */
3588 static int
3589 zfs_acl_node_aces_walk_init(mdb_walk_state_t *wsp)
3590 {
3591 	return (zfs_acl_node_aces_walk_init_common(wsp, 1));
3592 }
3593 
3594 /* ARGSUSED */
3595 static int
3596 zfs_acl_node_aces0_walk_init(mdb_walk_state_t *wsp)
3597 {
3598 	return (zfs_acl_node_aces_walk_init_common(wsp, 0));
3599 }
3600 
3601 static int
3602 zfs_aces_walk_step(mdb_walk_state_t *wsp)
3603 {
3604 	ace_walk_data_t *ace_data = wsp->walk_data;
3605 	zfs_ace_t zace;
3606 	ace_t *acep;
3607 	int status;
3608 	int entry_type;
3609 	int allow_type;
3610 	uintptr_t ptr;
3611 
3612 	if (ace_data->ace_count == 0)
3613 		return (WALK_DONE);
3614 
3615 	if (mdb_vread(&zace, sizeof (zfs_ace_t), wsp->walk_addr) == -1) {
3616 		mdb_warn("failed to read zfs_ace_t at %#lx",
3617 		    wsp->walk_addr);
3618 		return (WALK_ERR);
3619 	}
3620 
3621 	switch (ace_data->ace_version) {
3622 	case 0:
3623 		acep = (ace_t *)&zace;
3624 		entry_type = acep->a_flags & ACE_TYPE_FLAGS;
3625 		allow_type = acep->a_type;
3626 		break;
3627 	case 1:
3628 		entry_type = zace.z_hdr.z_flags & ACE_TYPE_FLAGS;
3629 		allow_type = zace.z_hdr.z_type;
3630 		break;
3631 	default:
3632 		return (WALK_ERR);
3633 	}
3634 
3635 	ptr = (uintptr_t)wsp->walk_addr;
3636 	switch (entry_type) {
3637 	case ACE_OWNER:
3638 	case ACE_EVERYONE:
3639 	case (ACE_IDENTIFIER_GROUP | ACE_GROUP):
3640 		ptr += ace_data->ace_version == 0 ?
3641 		    sizeof (ace_t) : sizeof (zfs_ace_hdr_t);
3642 		break;
3643 	case ACE_IDENTIFIER_GROUP:
3644 	default:
3645 		switch (allow_type) {
3646 		case ACE_ACCESS_ALLOWED_OBJECT_ACE_TYPE:
3647 		case ACE_ACCESS_DENIED_OBJECT_ACE_TYPE:
3648 		case ACE_SYSTEM_AUDIT_OBJECT_ACE_TYPE:
3649 		case ACE_SYSTEM_ALARM_OBJECT_ACE_TYPE:
3650 			ptr += ace_data->ace_version == 0 ?
3651 			    sizeof (ace_t) : sizeof (zfs_object_ace_t);
3652 			break;
3653 		default:
3654 			ptr += ace_data->ace_version == 0 ?
3655 			    sizeof (ace_t) : sizeof (zfs_ace_t);
3656 			break;
3657 		}
3658 	}
3659 
3660 	ace_data->ace_count--;
3661 	status = wsp->walk_callback(wsp->walk_addr,
3662 	    (void *)(uintptr_t)&zace, wsp->walk_cbdata);
3663 
3664 	wsp->walk_addr = ptr;
3665 	return (status);
3666 }
3667 
3668 typedef struct mdb_zfs_rrwlock {
3669 	uintptr_t	rr_writer;
3670 	boolean_t	rr_writer_wanted;
3671 } mdb_zfs_rrwlock_t;
3672 
3673 static uint_t rrw_key;
3674 
3675 /* ARGSUSED */
3676 static int
3677 rrwlock(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
3678 {
3679 	mdb_zfs_rrwlock_t rrw;
3680 
3681 	if (rrw_key == 0) {
3682 		if (mdb_ctf_readsym(&rrw_key, "uint_t", "rrw_tsd_key", 0) == -1)
3683 			return (DCMD_ERR);
3684 	}
3685 
3686 	if (mdb_ctf_vread(&rrw, "rrwlock_t", "mdb_zfs_rrwlock_t", addr,
3687 	    0) == -1)
3688 		return (DCMD_ERR);
3689 
3690 	if (rrw.rr_writer != 0) {
3691 		mdb_printf("write lock held by thread %lx\n", rrw.rr_writer);
3692 		return (DCMD_OK);
3693 	}
3694 
3695 	if (rrw.rr_writer_wanted) {
3696 		mdb_printf("writer wanted\n");
3697 	}
3698 
3699 	mdb_printf("anonymous references:\n");
3700 	(void) mdb_call_dcmd("refcount", addr +
3701 	    mdb_ctf_offsetof_by_name(ZFS_STRUCT "rrwlock", "rr_anon_rcount"),
3702 	    DCMD_ADDRSPEC, 0, NULL);
3703 
3704 	mdb_printf("linked references:\n");
3705 	(void) mdb_call_dcmd("refcount", addr +
3706 	    mdb_ctf_offsetof_by_name(ZFS_STRUCT "rrwlock", "rr_linked_rcount"),
3707 	    DCMD_ADDRSPEC, 0, NULL);
3708 
3709 	/*
3710 	 * XXX This should find references from
3711 	 * "::walk thread | ::tsd -v <rrw_key>", but there is no support
3712 	 * for programmatic consumption of dcmds, so this would be
3713 	 * difficult, potentially requiring reimplementing ::tsd (both
3714 	 * user and kernel versions) in this MDB module.
3715 	 */
3716 
3717 	return (DCMD_OK);
3718 }
3719 
3720 typedef struct mdb_arc_buf_hdr_t {
3721 	uint16_t b_psize;
3722 	uint16_t b_lsize;
3723 	struct {
3724 		uint32_t	b_bufcnt;
3725 		uintptr_t	b_state;
3726 	} b_l1hdr;
3727 } mdb_arc_buf_hdr_t;
3728 
3729 enum arc_cflags {
3730 	ARC_CFLAG_VERBOSE		= 1 << 0,
3731 	ARC_CFLAG_ANON			= 1 << 1,
3732 	ARC_CFLAG_MRU			= 1 << 2,
3733 	ARC_CFLAG_MFU			= 1 << 3,
3734 	ARC_CFLAG_BUFS			= 1 << 4,
3735 };
3736 
3737 typedef struct arc_compression_stats_data {
3738 	GElf_Sym anon_sym;	/* ARC_anon symbol */
3739 	GElf_Sym mru_sym;	/* ARC_mru symbol */
3740 	GElf_Sym mrug_sym;	/* ARC_mru_ghost symbol */
3741 	GElf_Sym mfu_sym;	/* ARC_mfu symbol */
3742 	GElf_Sym mfug_sym;	/* ARC_mfu_ghost symbol */
3743 	GElf_Sym l2c_sym;	/* ARC_l2c_only symbol */
3744 	uint64_t *anon_c_hist;	/* histogram of compressed sizes in anon */
3745 	uint64_t *anon_u_hist;	/* histogram of uncompressed sizes in anon */
3746 	uint64_t *anon_bufs;	/* histogram of buffer counts in anon state */
3747 	uint64_t *mru_c_hist;	/* histogram of compressed sizes in mru */
3748 	uint64_t *mru_u_hist;	/* histogram of uncompressed sizes in mru */
3749 	uint64_t *mru_bufs;	/* histogram of buffer counts in mru */
3750 	uint64_t *mfu_c_hist;	/* histogram of compressed sizes in mfu */
3751 	uint64_t *mfu_u_hist;	/* histogram of uncompressed sizes in mfu */
3752 	uint64_t *mfu_bufs;	/* histogram of buffer counts in mfu */
3753 	uint64_t *all_c_hist;	/* histogram of compressed anon + mru + mfu */
3754 	uint64_t *all_u_hist;	/* histogram of uncompressed anon + mru + mfu */
3755 	uint64_t *all_bufs;	/* histogram of buffer counts in all states  */
3756 	int arc_cflags;		/* arc compression flags, specified by user */
3757 	int hist_nbuckets;	/* number of buckets in each histogram */
3758 } arc_compression_stats_data_t;
3759 
3760 int
3761 highbit64(uint64_t i)
3762 {
3763 	int h = 1;
3764 
3765 	if (i == 0)
3766 		return (0);
3767 	if (i & 0xffffffff00000000ULL) {
3768 		h += 32; i >>= 32;
3769 	}
3770 	if (i & 0xffff0000) {
3771 		h += 16; i >>= 16;
3772 	}
3773 	if (i & 0xff00) {
3774 		h += 8; i >>= 8;
3775 	}
3776 	if (i & 0xf0) {
3777 		h += 4; i >>= 4;
3778 	}
3779 	if (i & 0xc) {
3780 		h += 2; i >>= 2;
3781 	}
3782 	if (i & 0x2) {
3783 		h += 1;
3784 	}
3785 	return (h);
3786 }
3787 
3788 /* ARGSUSED */
3789 static int
3790 arc_compression_stats_cb(uintptr_t addr, const void *unknown, void *arg)
3791 {
3792 	arc_compression_stats_data_t *data = arg;
3793 	mdb_arc_buf_hdr_t hdr;
3794 	int cbucket, ubucket, bufcnt;
3795 
3796 	if (mdb_ctf_vread(&hdr, "arc_buf_hdr_t", "mdb_arc_buf_hdr_t",
3797 	    addr, 0) == -1) {
3798 		return (WALK_ERR);
3799 	}
3800 
3801 	/*
3802 	 * Headers in the ghost states, or the l2c_only state don't have
3803 	 * arc buffers linked off of them. Thus, their compressed size
3804 	 * is meaningless, so we skip these from the stats.
3805 	 */
3806 	if (hdr.b_l1hdr.b_state == data->mrug_sym.st_value ||
3807 	    hdr.b_l1hdr.b_state == data->mfug_sym.st_value ||
3808 	    hdr.b_l1hdr.b_state == data->l2c_sym.st_value) {
3809 		return (WALK_NEXT);
3810 	}
3811 
3812 	/*
3813 	 * The physical size (compressed) and logical size
3814 	 * (uncompressed) are in units of SPA_MINBLOCKSIZE. By default,
3815 	 * we use the log2 of this value (rounded down to the nearest
3816 	 * integer) to determine the bucket to assign this header to.
3817 	 * Thus, the histogram is logarithmic with respect to the size
3818 	 * of the header. For example, the following is a mapping of the
3819 	 * bucket numbers and the range of header sizes they correspond to:
3820 	 *
3821 	 *	0: 0 byte headers
3822 	 *	1: 512 byte headers
3823 	 *	2: [1024 - 2048) byte headers
3824 	 *	3: [2048 - 4096) byte headers
3825 	 *	4: [4096 - 8192) byte headers
3826 	 *	5: [8192 - 16394) byte headers
3827 	 *	6: [16384 - 32768) byte headers
3828 	 *	7: [32768 - 65536) byte headers
3829 	 *	8: [65536 - 131072) byte headers
3830 	 *	9: 131072 byte headers
3831 	 *
3832 	 * If the ARC_CFLAG_VERBOSE flag was specified, we use the
3833 	 * physical and logical sizes directly. Thus, the histogram will
3834 	 * no longer be logarithmic; instead it will be linear with
3835 	 * respect to the size of the header. The following is a mapping
3836 	 * of the first many bucket numbers and the header size they
3837 	 * correspond to:
3838 	 *
3839 	 *	0: 0 byte headers
3840 	 *	1: 512 byte headers
3841 	 *	2: 1024 byte headers
3842 	 *	3: 1536 byte headers
3843 	 *	4: 2048 byte headers
3844 	 *	5: 2560 byte headers
3845 	 *	6: 3072 byte headers
3846 	 *
3847 	 * And so on. Keep in mind that a range of sizes isn't used in
3848 	 * the case of linear scale because the headers can only
3849 	 * increment or decrement in sizes of 512 bytes. So, it's not
3850 	 * possible for a header to be sized in between whats listed
3851 	 * above.
3852 	 *
3853 	 * Also, the above mapping values were calculated assuming a
3854 	 * SPA_MINBLOCKSHIFT of 512 bytes and a SPA_MAXBLOCKSIZE of 128K.
3855 	 */
3856 
3857 	if (data->arc_cflags & ARC_CFLAG_VERBOSE) {
3858 		cbucket = hdr.b_psize;
3859 		ubucket = hdr.b_lsize;
3860 	} else {
3861 		cbucket = highbit64(hdr.b_psize);
3862 		ubucket = highbit64(hdr.b_lsize);
3863 	}
3864 
3865 	bufcnt = hdr.b_l1hdr.b_bufcnt;
3866 	if (bufcnt >= data->hist_nbuckets)
3867 		bufcnt = data->hist_nbuckets - 1;
3868 
3869 	/* Ensure we stay within the bounds of the histogram array */
3870 	ASSERT3U(cbucket, <, data->hist_nbuckets);
3871 	ASSERT3U(ubucket, <, data->hist_nbuckets);
3872 
3873 	if (hdr.b_l1hdr.b_state == data->anon_sym.st_value) {
3874 		data->anon_c_hist[cbucket]++;
3875 		data->anon_u_hist[ubucket]++;
3876 		data->anon_bufs[bufcnt]++;
3877 	} else if (hdr.b_l1hdr.b_state == data->mru_sym.st_value) {
3878 		data->mru_c_hist[cbucket]++;
3879 		data->mru_u_hist[ubucket]++;
3880 		data->mru_bufs[bufcnt]++;
3881 	} else if (hdr.b_l1hdr.b_state == data->mfu_sym.st_value) {
3882 		data->mfu_c_hist[cbucket]++;
3883 		data->mfu_u_hist[ubucket]++;
3884 		data->mfu_bufs[bufcnt]++;
3885 	}
3886 
3887 	data->all_c_hist[cbucket]++;
3888 	data->all_u_hist[ubucket]++;
3889 	data->all_bufs[bufcnt]++;
3890 
3891 	return (WALK_NEXT);
3892 }
3893 
3894 /* ARGSUSED */
3895 static int
3896 arc_compression_stats(uintptr_t addr, uint_t flags, int argc,
3897     const mdb_arg_t *argv)
3898 {
3899 	arc_compression_stats_data_t data = { 0 };
3900 	unsigned int max_shifted = SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT;
3901 	unsigned int hist_size;
3902 	char range[32];
3903 	int rc = DCMD_OK;
3904 
3905 	if (mdb_getopts(argc, argv,
3906 	    'v', MDB_OPT_SETBITS, ARC_CFLAG_VERBOSE, &data.arc_cflags,
3907 	    'a', MDB_OPT_SETBITS, ARC_CFLAG_ANON, &data.arc_cflags,
3908 	    'b', MDB_OPT_SETBITS, ARC_CFLAG_BUFS, &data.arc_cflags,
3909 	    'r', MDB_OPT_SETBITS, ARC_CFLAG_MRU, &data.arc_cflags,
3910 	    'f', MDB_OPT_SETBITS, ARC_CFLAG_MFU, &data.arc_cflags) != argc)
3911 		return (DCMD_USAGE);
3912 
3913 	if (mdb_lookup_by_obj(ZFS_OBJ_NAME, "ARC_anon", &data.anon_sym) ||
3914 	    mdb_lookup_by_obj(ZFS_OBJ_NAME, "ARC_mru", &data.mru_sym) ||
3915 	    mdb_lookup_by_obj(ZFS_OBJ_NAME, "ARC_mru_ghost", &data.mrug_sym) ||
3916 	    mdb_lookup_by_obj(ZFS_OBJ_NAME, "ARC_mfu", &data.mfu_sym) ||
3917 	    mdb_lookup_by_obj(ZFS_OBJ_NAME, "ARC_mfu_ghost", &data.mfug_sym) ||
3918 	    mdb_lookup_by_obj(ZFS_OBJ_NAME, "ARC_l2c_only", &data.l2c_sym)) {
3919 		mdb_warn("can't find arc state symbol");
3920 		return (DCMD_ERR);
3921 	}
3922 
3923 	/*
3924 	 * Determine the maximum expected size for any header, and use
3925 	 * this to determine the number of buckets needed for each
3926 	 * histogram. If ARC_CFLAG_VERBOSE is specified, this value is
3927 	 * used directly; otherwise the log2 of the maximum size is
3928 	 * used. Thus, if using a log2 scale there's a maximum of 10
3929 	 * possible buckets, while the linear scale (when using
3930 	 * ARC_CFLAG_VERBOSE) has a maximum of 257 buckets.
3931 	 */
3932 	if (data.arc_cflags & ARC_CFLAG_VERBOSE)
3933 		data.hist_nbuckets = max_shifted + 1;
3934 	else
3935 		data.hist_nbuckets = highbit64(max_shifted) + 1;
3936 
3937 	hist_size = sizeof (uint64_t) * data.hist_nbuckets;
3938 
3939 	data.anon_c_hist = mdb_zalloc(hist_size, UM_SLEEP);
3940 	data.anon_u_hist = mdb_zalloc(hist_size, UM_SLEEP);
3941 	data.anon_bufs = mdb_zalloc(hist_size, UM_SLEEP);
3942 
3943 	data.mru_c_hist = mdb_zalloc(hist_size, UM_SLEEP);
3944 	data.mru_u_hist = mdb_zalloc(hist_size, UM_SLEEP);
3945 	data.mru_bufs = mdb_zalloc(hist_size, UM_SLEEP);
3946 
3947 	data.mfu_c_hist = mdb_zalloc(hist_size, UM_SLEEP);
3948 	data.mfu_u_hist = mdb_zalloc(hist_size, UM_SLEEP);
3949 	data.mfu_bufs = mdb_zalloc(hist_size, UM_SLEEP);
3950 
3951 	data.all_c_hist = mdb_zalloc(hist_size, UM_SLEEP);
3952 	data.all_u_hist = mdb_zalloc(hist_size, UM_SLEEP);
3953 	data.all_bufs = mdb_zalloc(hist_size, UM_SLEEP);
3954 
3955 	if (mdb_walk("arc_buf_hdr_t_full", arc_compression_stats_cb,
3956 	    &data) != 0) {
3957 		mdb_warn("can't walk arc_buf_hdr's");
3958 		rc = DCMD_ERR;
3959 		goto out;
3960 	}
3961 
3962 	if (data.arc_cflags & ARC_CFLAG_VERBOSE) {
3963 		rc = mdb_snprintf(range, sizeof (range),
3964 		    "[n*%llu, (n+1)*%llu)", SPA_MINBLOCKSIZE,
3965 		    SPA_MINBLOCKSIZE);
3966 	} else {
3967 		rc = mdb_snprintf(range, sizeof (range),
3968 		    "[2^(n-1)*%llu, 2^n*%llu)", SPA_MINBLOCKSIZE,
3969 		    SPA_MINBLOCKSIZE);
3970 	}
3971 
3972 	if (rc < 0) {
3973 		/* snprintf failed, abort the dcmd */
3974 		rc = DCMD_ERR;
3975 		goto out;
3976 	} else {
3977 		/* snprintf succeeded above, reset return code */
3978 		rc = DCMD_OK;
3979 	}
3980 
3981 	if (data.arc_cflags & ARC_CFLAG_ANON) {
3982 		if (data.arc_cflags & ARC_CFLAG_BUFS) {
3983 			mdb_printf("Histogram of the number of anon buffers "
3984 			    "that are associated with an arc hdr.\n");
3985 			dump_histogram(data.anon_bufs, data.hist_nbuckets, 0);
3986 			mdb_printf("\n");
3987 		}
3988 		mdb_printf("Histogram of compressed anon buffers.\n"
3989 		    "Each bucket represents buffers of size: %s.\n", range);
3990 		dump_histogram(data.anon_c_hist, data.hist_nbuckets, 0);
3991 		mdb_printf("\n");
3992 
3993 		mdb_printf("Histogram of uncompressed anon buffers.\n"
3994 		    "Each bucket represents buffers of size: %s.\n", range);
3995 		dump_histogram(data.anon_u_hist, data.hist_nbuckets, 0);
3996 		mdb_printf("\n");
3997 	}
3998 
3999 	if (data.arc_cflags & ARC_CFLAG_MRU) {
4000 		if (data.arc_cflags & ARC_CFLAG_BUFS) {
4001 			mdb_printf("Histogram of the number of mru buffers "
4002 			    "that are associated with an arc hdr.\n");
4003 			dump_histogram(data.mru_bufs, data.hist_nbuckets, 0);
4004 			mdb_printf("\n");
4005 		}
4006 		mdb_printf("Histogram of compressed mru buffers.\n"
4007 		    "Each bucket represents buffers of size: %s.\n", range);
4008 		dump_histogram(data.mru_c_hist, data.hist_nbuckets, 0);
4009 		mdb_printf("\n");
4010 
4011 		mdb_printf("Histogram of uncompressed mru buffers.\n"
4012 		    "Each bucket represents buffers of size: %s.\n", range);
4013 		dump_histogram(data.mru_u_hist, data.hist_nbuckets, 0);
4014 		mdb_printf("\n");
4015 	}
4016 
4017 	if (data.arc_cflags & ARC_CFLAG_MFU) {
4018 		if (data.arc_cflags & ARC_CFLAG_BUFS) {
4019 			mdb_printf("Histogram of the number of mfu buffers "
4020 			    "that are associated with an arc hdr.\n");
4021 			dump_histogram(data.mfu_bufs, data.hist_nbuckets, 0);
4022 			mdb_printf("\n");
4023 		}
4024 
4025 		mdb_printf("Histogram of compressed mfu buffers.\n"
4026 		    "Each bucket represents buffers of size: %s.\n", range);
4027 		dump_histogram(data.mfu_c_hist, data.hist_nbuckets, 0);
4028 		mdb_printf("\n");
4029 
4030 		mdb_printf("Histogram of uncompressed mfu buffers.\n"
4031 		    "Each bucket represents buffers of size: %s.\n", range);
4032 		dump_histogram(data.mfu_u_hist, data.hist_nbuckets, 0);
4033 		mdb_printf("\n");
4034 	}
4035 
4036 	if (data.arc_cflags & ARC_CFLAG_BUFS) {
4037 		mdb_printf("Histogram of all buffers that "
4038 		    "are associated with an arc hdr.\n");
4039 		dump_histogram(data.all_bufs, data.hist_nbuckets, 0);
4040 		mdb_printf("\n");
4041 	}
4042 
4043 	mdb_printf("Histogram of all compressed buffers.\n"
4044 	    "Each bucket represents buffers of size: %s.\n", range);
4045 	dump_histogram(data.all_c_hist, data.hist_nbuckets, 0);
4046 	mdb_printf("\n");
4047 
4048 	mdb_printf("Histogram of all uncompressed buffers.\n"
4049 	    "Each bucket represents buffers of size: %s.\n", range);
4050 	dump_histogram(data.all_u_hist, data.hist_nbuckets, 0);
4051 
4052 out:
4053 	mdb_free(data.anon_c_hist, hist_size);
4054 	mdb_free(data.anon_u_hist, hist_size);
4055 	mdb_free(data.anon_bufs, hist_size);
4056 
4057 	mdb_free(data.mru_c_hist, hist_size);
4058 	mdb_free(data.mru_u_hist, hist_size);
4059 	mdb_free(data.mru_bufs, hist_size);
4060 
4061 	mdb_free(data.mfu_c_hist, hist_size);
4062 	mdb_free(data.mfu_u_hist, hist_size);
4063 	mdb_free(data.mfu_bufs, hist_size);
4064 
4065 	mdb_free(data.all_c_hist, hist_size);
4066 	mdb_free(data.all_u_hist, hist_size);
4067 	mdb_free(data.all_bufs, hist_size);
4068 
4069 	return (rc);
4070 }
4071 
4072 /*
4073  * MDB module linkage information:
4074  *
4075  * We declare a list of structures describing our dcmds, and a function
4076  * named _mdb_init to return a pointer to our module information.
4077  */
4078 
4079 static const mdb_dcmd_t dcmds[] = {
4080 	{ "arc", "[-bkmg]", "print ARC variables", arc_print },
4081 	{ "blkptr", ":", "print blkptr_t", blkptr },
4082 	{ "dva", ":", "print dva_t", dva },
4083 	{ "dbuf", ":", "print dmu_buf_impl_t", dbuf },
4084 	{ "dbuf_stats", ":", "dbuf stats", dbuf_stats },
4085 	{ "dbufs",
4086 	    "\t[-O objset_t*] [-n objset_name | \"mos\"] "
4087 	    "[-o object | \"mdn\"] \n"
4088 	    "\t[-l level] [-b blkid | \"bonus\"]",
4089 	    "find dmu_buf_impl_t's that match specified criteria", dbufs },
4090 	{ "abuf_find", "dva_word[0] dva_word[1]",
4091 	    "find arc_buf_hdr_t of a specified DVA",
4092 	    abuf_find },
4093 	{ "spa", "?[-cevmMh]\n"
4094 	    "\t-c display spa config\n"
4095 	    "\t-e display vdev statistics\n"
4096 	    "\t-v display vdev information\n"
4097 	    "\t-m display metaslab statistics\n"
4098 	    "\t-M display metaslab group statistics\n"
4099 	    "\t-h display histogram (requires -m or -M)\n",
4100 	    "spa_t summary", spa_print },
4101 	{ "spa_config", ":", "print spa_t configuration", spa_print_config },
4102 	{ "spa_space", ":[-b]", "print spa_t on-disk space usage", spa_space },
4103 	{ "spa_vdevs", ":[-emMh]\n"
4104 	    "\t-e display vdev statistics\n"
4105 	    "\t-m dispaly metaslab statistics\n"
4106 	    "\t-M display metaslab group statistic\n"
4107 	    "\t-h display histogram (requires -m or -M)\n",
4108 	    "given a spa_t, print vdev summary", spa_vdevs },
4109 	{ "sm_entries", "<buffer length in bytes>",
4110 	    "print out space map entries from a buffer decoded",
4111 	    sm_entries},
4112 	{ "vdev", ":[-remMh]\n"
4113 	    "\t-r display recursively\n"
4114 	    "\t-e display statistics\n"
4115 	    "\t-m display metaslab statistics (top level vdev only)\n"
4116 	    "\t-M display metaslab group statistics (top level vdev only)\n"
4117 	    "\t-h display histogram (requires -m or -M)\n",
4118 	    "vdev_t summary", vdev_print },
4119 	{ "zio", ":[-cpr]\n"
4120 	    "\t-c display children\n"
4121 	    "\t-p display parents\n"
4122 	    "\t-r display recursively",
4123 	    "zio_t summary", zio_print },
4124 	{ "zio_state", "?", "print out all zio_t structures on system or "
4125 	    "for a particular pool", zio_state },
4126 	{ "zfs_blkstats", ":[-v]",
4127 	    "given a spa_t, print block type stats from last scrub",
4128 	    zfs_blkstats },
4129 	{ "zfs_params", "", "print zfs tunable parameters", zfs_params },
4130 	{ "refcount", ":[-r]\n"
4131 	    "\t-r display recently removed references",
4132 	    "print refcount_t holders", refcount },
4133 	{ "zap_leaf", "", "print zap_leaf_phys_t", zap_leaf },
4134 	{ "zfs_aces", ":[-v]", "print all ACEs from a zfs_acl_t",
4135 	    zfs_acl_dump },
4136 	{ "zfs_ace", ":[-v]", "print zfs_ace", zfs_ace_print },
4137 	{ "zfs_ace0", ":[-v]", "print zfs_ace0", zfs_ace0_print },
4138 	{ "sa_attr_table", ":", "print SA attribute table from sa_os_t",
4139 	    sa_attr_table},
4140 	{ "sa_attr", ": attr_id",
4141 	    "print SA attribute address when given sa_handle_t", sa_attr_print},
4142 	{ "zfs_dbgmsg", ":[-va]",
4143 	    "print zfs debug log", dbgmsg},
4144 	{ "rrwlock", ":",
4145 	    "print rrwlock_t, including readers", rrwlock},
4146 	{ "metaslab_weight", "weight",
4147 	    "print metaslab weight", metaslab_weight},
4148 	{ "metaslab_trace", ":",
4149 	    "print metaslab allocation trace records", metaslab_trace},
4150 	{ "arc_compression_stats", ":[-vabrf]\n"
4151 	    "\t-v verbose, display a linearly scaled histogram\n"
4152 	    "\t-a display ARC_anon state statistics individually\n"
4153 	    "\t-r display ARC_mru state statistics individually\n"
4154 	    "\t-f display ARC_mfu state statistics individually\n"
4155 	    "\t-b display histogram of buffer counts\n",
4156 	    "print a histogram of compressed arc buffer sizes",
4157 	    arc_compression_stats},
4158 	{ NULL }
4159 };
4160 
4161 static const mdb_walker_t walkers[] = {
4162 	{ "txg_list", "given any txg_list_t *, walk all entries in all txgs",
4163 	    txg_list_walk_init, txg_list_walk_step, NULL },
4164 	{ "txg_list0", "given any txg_list_t *, walk all entries in txg 0",
4165 	    txg_list0_walk_init, txg_list_walk_step, NULL },
4166 	{ "txg_list1", "given any txg_list_t *, walk all entries in txg 1",
4167 	    txg_list1_walk_init, txg_list_walk_step, NULL },
4168 	{ "txg_list2", "given any txg_list_t *, walk all entries in txg 2",
4169 	    txg_list2_walk_init, txg_list_walk_step, NULL },
4170 	{ "txg_list3", "given any txg_list_t *, walk all entries in txg 3",
4171 	    txg_list3_walk_init, txg_list_walk_step, NULL },
4172 	{ "zio", "walk all zio structures, optionally for a particular spa_t",
4173 	    zio_walk_init, zio_walk_step, NULL },
4174 	{ "zio_root",
4175 	    "walk all root zio_t structures, optionally for a particular spa_t",
4176 	    zio_walk_init, zio_walk_root_step, NULL },
4177 	{ "spa", "walk all spa_t entries in the namespace",
4178 	    spa_walk_init, spa_walk_step, NULL },
4179 	{ "metaslab", "given a spa_t *, walk all metaslab_t structures",
4180 	    metaslab_walk_init, metaslab_walk_step, NULL },
4181 	{ "multilist", "given a multilist_t *, walk all list_t structures",
4182 	    multilist_walk_init, multilist_walk_step, NULL },
4183 	{ "zfs_acl_node", "given a zfs_acl_t, walk all zfs_acl_nodes",
4184 	    zfs_acl_node_walk_init, zfs_acl_node_walk_step, NULL },
4185 	{ "zfs_acl_node_aces", "given a zfs_acl_node_t, walk all ACEs",
4186 	    zfs_acl_node_aces_walk_init, zfs_aces_walk_step, NULL },
4187 	{ "zfs_acl_node_aces0",
4188 	    "given a zfs_acl_node_t, walk all ACEs as ace_t",
4189 	    zfs_acl_node_aces0_walk_init, zfs_aces_walk_step, NULL },
4190 	{ NULL }
4191 };
4192 
4193 static const mdb_modinfo_t modinfo = {
4194 	MDB_API_VERSION, dcmds, walkers
4195 };
4196 
4197 const mdb_modinfo_t *
4198 _mdb_init(void)
4199 {
4200 	return (&modinfo);
4201 }
4202