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 https://opensource.org/licenses/CDDL-1.0.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21/*
22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright (c) 2012, 2018 by Delphix. All rights reserved.
24 * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
25 */
26
27#ifndef	_SYS_DNODE_H
28#define	_SYS_DNODE_H
29
30#include <sys/zfs_context.h>
31#include <sys/avl.h>
32#include <sys/spa.h>
33#include <sys/txg.h>
34#include <sys/zio.h>
35#include <sys/zfs_refcount.h>
36#include <sys/dmu_zfetch.h>
37#include <sys/zrlock.h>
38#include <sys/multilist.h>
39#include <sys/wmsum.h>
40
41#ifdef	__cplusplus
42extern "C" {
43#endif
44
45/*
46 * dnode_hold() flags.
47 */
48#define	DNODE_MUST_BE_ALLOCATED	1
49#define	DNODE_MUST_BE_FREE	2
50#define	DNODE_DRY_RUN		4
51
52/*
53 * dnode_next_offset() flags.
54 */
55#define	DNODE_FIND_HOLE		1
56#define	DNODE_FIND_BACKWARDS	2
57#define	DNODE_FIND_HAVELOCK	4
58
59/*
60 * Fixed constants.
61 */
62#define	DNODE_SHIFT		9	/* 512 bytes */
63#define	DN_MIN_INDBLKSHIFT	12	/* 4k */
64/*
65 * If we ever increase this value beyond 20, we need to revisit all logic that
66 * does x << level * ebps to handle overflow.  With a 1M indirect block size,
67 * 4 levels of indirect blocks would not be able to guarantee addressing an
68 * entire object, so 5 levels will be used, but 5 * (20 - 7) = 65.
69 */
70#define	DN_MAX_INDBLKSHIFT	17	/* 128k */
71#define	DNODE_BLOCK_SHIFT	14	/* 16k */
72#define	DNODE_CORE_SIZE		64	/* 64 bytes for dnode sans blkptrs */
73#define	DN_MAX_OBJECT_SHIFT	48	/* 256 trillion (zfs_fid_t limit) */
74#define	DN_MAX_OFFSET_SHIFT	64	/* 2^64 bytes in a dnode */
75
76/*
77 * dnode id flags
78 *
79 * Note: a file will never ever have its ids moved from bonus->spill
80 */
81#define	DN_ID_CHKED_BONUS	0x1
82#define	DN_ID_CHKED_SPILL	0x2
83#define	DN_ID_OLD_EXIST		0x4
84#define	DN_ID_NEW_EXIST		0x8
85
86/*
87 * Derived constants.
88 */
89#define	DNODE_MIN_SIZE		(1 << DNODE_SHIFT)
90#define	DNODE_MAX_SIZE		(1 << DNODE_BLOCK_SHIFT)
91#define	DNODE_BLOCK_SIZE	(1 << DNODE_BLOCK_SHIFT)
92#define	DNODE_MIN_SLOTS		(DNODE_MIN_SIZE >> DNODE_SHIFT)
93#define	DNODE_MAX_SLOTS		(DNODE_MAX_SIZE >> DNODE_SHIFT)
94#define	DN_BONUS_SIZE(dnsize)	((dnsize) - DNODE_CORE_SIZE - \
95	(1 << SPA_BLKPTRSHIFT))
96#define	DN_SLOTS_TO_BONUSLEN(slots)	DN_BONUS_SIZE((slots) << DNODE_SHIFT)
97#define	DN_OLD_MAX_BONUSLEN	(DN_BONUS_SIZE(DNODE_MIN_SIZE))
98#define	DN_MAX_NBLKPTR	((DNODE_MIN_SIZE - DNODE_CORE_SIZE) >> SPA_BLKPTRSHIFT)
99#define	DN_MAX_OBJECT	(1ULL << DN_MAX_OBJECT_SHIFT)
100#define	DN_ZERO_BONUSLEN	(DN_BONUS_SIZE(DNODE_MAX_SIZE) + 1)
101#define	DN_KILL_SPILLBLK (1)
102
103#define	DN_SLOT_UNINIT		((void *)NULL)	/* Uninitialized */
104#define	DN_SLOT_FREE		((void *)1UL)	/* Free slot */
105#define	DN_SLOT_ALLOCATED	((void *)2UL)	/* Allocated slot */
106#define	DN_SLOT_INTERIOR	((void *)3UL)	/* Interior allocated slot */
107#define	DN_SLOT_IS_PTR(dn)	((void *)dn > DN_SLOT_INTERIOR)
108#define	DN_SLOT_IS_VALID(dn)	((void *)dn != NULL)
109
110#define	DNODES_PER_BLOCK_SHIFT	(DNODE_BLOCK_SHIFT - DNODE_SHIFT)
111#define	DNODES_PER_BLOCK	(1ULL << DNODES_PER_BLOCK_SHIFT)
112
113/*
114 * This is inaccurate if the indblkshift of the particular object is not the
115 * max.  But it's only used by userland to calculate the zvol reservation.
116 */
117#define	DNODES_PER_LEVEL_SHIFT	(DN_MAX_INDBLKSHIFT - SPA_BLKPTRSHIFT)
118#define	DNODES_PER_LEVEL	(1ULL << DNODES_PER_LEVEL_SHIFT)
119
120#define	DN_MAX_LEVELS	(DIV_ROUND_UP(DN_MAX_OFFSET_SHIFT - SPA_MINBLOCKSHIFT, \
121	DN_MIN_INDBLKSHIFT - SPA_BLKPTRSHIFT) + 1)
122
123/*
124 * Use the flexible array instead of the fixed length one dn_bonus
125 * to address memcpy/memmove fortify error
126 */
127#define	DN_BONUS(dnp)	((void*)((dnp)->dn_bonus_flexible + \
128	(((dnp)->dn_nblkptr - 1) * sizeof (blkptr_t))))
129#define	DN_MAX_BONUS_LEN(dnp) \
130	((dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) ? \
131	(uint8_t *)DN_SPILL_BLKPTR(dnp) - (uint8_t *)DN_BONUS(dnp) : \
132	(uint8_t *)(dnp + (dnp->dn_extra_slots + 1)) - (uint8_t *)DN_BONUS(dnp))
133
134#define	DN_USED_BYTES(dnp) (((dnp)->dn_flags & DNODE_FLAG_USED_BYTES) ? \
135	(dnp)->dn_used : (dnp)->dn_used << SPA_MINBLOCKSHIFT)
136
137#define	EPB(blkshift, typeshift)	(1 << (blkshift - typeshift))
138
139struct dmu_buf_impl;
140struct objset;
141struct zio;
142
143enum dnode_dirtycontext {
144	DN_UNDIRTIED,
145	DN_DIRTY_OPEN,
146	DN_DIRTY_SYNC
147};
148
149/* Is dn_used in bytes?  if not, it's in multiples of SPA_MINBLOCKSIZE */
150#define	DNODE_FLAG_USED_BYTES			(1 << 0)
151#define	DNODE_FLAG_USERUSED_ACCOUNTED		(1 << 1)
152
153/* Does dnode have a SA spill blkptr in bonus? */
154#define	DNODE_FLAG_SPILL_BLKPTR			(1 << 2)
155
156/* User/Group/Project dnode accounting */
157#define	DNODE_FLAG_USEROBJUSED_ACCOUNTED	(1 << 3)
158
159/*
160 * This mask defines the set of flags which are "portable", meaning
161 * that they can be preserved when doing a raw encrypted zfs send.
162 * Flags included in this mask will be protected by AAD when the block
163 * of dnodes is encrypted.
164 */
165#define	DNODE_CRYPT_PORTABLE_FLAGS_MASK		(DNODE_FLAG_SPILL_BLKPTR)
166
167/*
168 * VARIABLE-LENGTH (LARGE) DNODES
169 *
170 * The motivation for variable-length dnodes is to eliminate the overhead
171 * associated with using spill blocks.  Spill blocks are used to store
172 * system attribute data (i.e. file metadata) that does not fit in the
173 * dnode's bonus buffer. By allowing a larger bonus buffer area the use of
174 * a spill block can be avoided.  Spill blocks potentially incur an
175 * additional read I/O for every dnode in a dnode block. As a worst case
176 * example, reading 32 dnodes from a 16k dnode block and all of the spill
177 * blocks could issue 33 separate reads. Now suppose those dnodes have size
178 * 1024 and therefore don't need spill blocks. Then the worst case number
179 * of blocks read is reduced from 33 to two--one per dnode block.
180 *
181 * ZFS-on-Linux systems that make heavy use of extended attributes benefit
182 * from this feature. In particular, ZFS-on-Linux supports the xattr=sa
183 * dataset property which allows file extended attribute data to be stored
184 * in the dnode bonus buffer as an alternative to the traditional
185 * directory-based format. Workloads such as SELinux and the Lustre
186 * distributed filesystem often store enough xattr data to force spill
187 * blocks when xattr=sa is in effect. Large dnodes may therefore provide a
188 * performance benefit to such systems. Other use cases that benefit from
189 * this feature include files with large ACLs and symbolic links with long
190 * target names.
191 *
192 * The size of a dnode may be a multiple of 512 bytes up to the size of a
193 * dnode block (currently 16384 bytes). The dn_extra_slots field of the
194 * on-disk dnode_phys_t structure describes the size of the physical dnode
195 * on disk. The field represents how many "extra" dnode_phys_t slots a
196 * dnode consumes in its dnode block. This convention results in a value of
197 * 0 for 512 byte dnodes which preserves on-disk format compatibility with
198 * older software which doesn't support large dnodes.
199 *
200 * Similarly, the in-memory dnode_t structure has a dn_num_slots field
201 * to represent the total number of dnode_phys_t slots consumed on disk.
202 * Thus dn->dn_num_slots is 1 greater than the corresponding
203 * dnp->dn_extra_slots. This difference in convention was adopted
204 * because, unlike on-disk structures, backward compatibility is not a
205 * concern for in-memory objects, so we used a more natural way to
206 * represent size for a dnode_t.
207 *
208 * The default size for newly created dnodes is determined by the value of
209 * the "dnodesize" dataset property. By default the property is set to
210 * "legacy" which is compatible with older software. Setting the property
211 * to "auto" will allow the filesystem to choose the most suitable dnode
212 * size. Currently this just sets the default dnode size to 1k, but future
213 * code improvements could dynamically choose a size based on observed
214 * workload patterns. Dnodes of varying sizes can coexist within the same
215 * dataset and even within the same dnode block.
216 */
217
218typedef struct dnode_phys {
219	uint8_t dn_type;		/* dmu_object_type_t */
220	uint8_t dn_indblkshift;		/* ln2(indirect block size) */
221	uint8_t dn_nlevels;		/* 1=dn_blkptr->data blocks */
222	uint8_t dn_nblkptr;		/* length of dn_blkptr */
223	uint8_t dn_bonustype;		/* type of data in bonus buffer */
224	uint8_t	dn_checksum;		/* ZIO_CHECKSUM type */
225	uint8_t	dn_compress;		/* ZIO_COMPRESS type */
226	uint8_t dn_flags;		/* DNODE_FLAG_* */
227	uint16_t dn_datablkszsec;	/* data block size in 512b sectors */
228	uint16_t dn_bonuslen;		/* length of dn_bonus */
229	uint8_t dn_extra_slots;		/* # of subsequent slots consumed */
230	uint8_t dn_pad2[3];
231
232	/* accounting is protected by dn_dirty_mtx */
233	uint64_t dn_maxblkid;		/* largest allocated block ID */
234	uint64_t dn_used;		/* bytes (or sectors) of disk space */
235
236	/*
237	 * Both dn_pad2 and dn_pad3 are protected by the block's MAC. This
238	 * allows us to protect any fields that might be added here in the
239	 * future. In either case, developers will want to check
240	 * zio_crypt_init_uios_dnode() and zio_crypt_do_dnode_hmac_updates()
241	 * to ensure the new field is being protected and updated properly.
242	 */
243	uint64_t dn_pad3[4];
244
245	/*
246	 * The tail region is 448 bytes for a 512 byte dnode, and
247	 * correspondingly larger for larger dnode sizes. The spill
248	 * block pointer, when present, is always at the end of the tail
249	 * region. There are three ways this space may be used, using
250	 * a 512 byte dnode for this diagram:
251	 *
252	 * 0       64      128     192     256     320     384     448 (offset)
253	 * +---------------+---------------+---------------+-------+
254	 * | dn_blkptr[0]  | dn_blkptr[1]  | dn_blkptr[2]  | /     |
255	 * +---------------+---------------+---------------+-------+
256	 * | dn_blkptr[0]  | dn_bonus[0..319]                      |
257	 * +---------------+-----------------------+---------------+
258	 * | dn_blkptr[0]  | dn_bonus[0..191]      | dn_spill      |
259	 * +---------------+-----------------------+---------------+
260	 */
261	union {
262		blkptr_t dn_blkptr[1+DN_OLD_MAX_BONUSLEN/sizeof (blkptr_t)];
263		struct {
264			blkptr_t __dn_ignore1;
265			uint8_t dn_bonus[DN_OLD_MAX_BONUSLEN];
266		};
267		struct {
268			blkptr_t __dn_ignore2;
269			uint8_t __dn_ignore3[DN_OLD_MAX_BONUSLEN -
270			    sizeof (blkptr_t)];
271			blkptr_t dn_spill;
272		};
273		struct {
274			blkptr_t __dn_ignore4;
275			uint8_t dn_bonus_flexible[];
276		};
277	};
278} dnode_phys_t;
279
280#define	DN_SPILL_BLKPTR(dnp)	((blkptr_t *)((char *)(dnp) + \
281	(((dnp)->dn_extra_slots + 1) << DNODE_SHIFT) - (1 << SPA_BLKPTRSHIFT)))
282
283struct dnode {
284	/*
285	 * Protects the structure of the dnode, including the number of levels
286	 * of indirection (dn_nlevels), dn_maxblkid, and dn_next_*
287	 */
288	krwlock_t dn_struct_rwlock;
289
290	/* Our link on dn_objset->os_dnodes list; protected by os_lock.  */
291	list_node_t dn_link;
292
293	/* immutable: */
294	struct objset *dn_objset;
295	uint64_t dn_object;
296	struct dmu_buf_impl *dn_dbuf;
297	struct dnode_handle *dn_handle;
298	dnode_phys_t *dn_phys; /* pointer into dn->dn_dbuf->db.db_data */
299
300	/*
301	 * Copies of stuff in dn_phys.  They're valid in the open
302	 * context (eg. even before the dnode is first synced).
303	 * Where necessary, these are protected by dn_struct_rwlock.
304	 */
305	dmu_object_type_t dn_type;	/* object type */
306	uint16_t dn_bonuslen;		/* bonus length */
307	uint8_t dn_bonustype;		/* bonus type */
308	uint8_t dn_nblkptr;		/* number of blkptrs (immutable) */
309	uint8_t dn_checksum;		/* ZIO_CHECKSUM type */
310	uint8_t dn_compress;		/* ZIO_COMPRESS type */
311	uint8_t dn_nlevels;
312	uint8_t dn_indblkshift;
313	uint8_t dn_datablkshift;	/* zero if blksz not power of 2! */
314	uint8_t dn_moved;		/* Has this dnode been moved? */
315	uint16_t dn_datablkszsec;	/* in 512b sectors */
316	uint32_t dn_datablksz;		/* in bytes */
317	uint64_t dn_maxblkid;
318	uint8_t dn_next_type[TXG_SIZE];
319	uint8_t dn_num_slots;		/* metadnode slots consumed on disk */
320	uint8_t dn_next_nblkptr[TXG_SIZE];
321	uint8_t dn_next_nlevels[TXG_SIZE];
322	uint8_t dn_next_indblkshift[TXG_SIZE];
323	uint8_t dn_next_bonustype[TXG_SIZE];
324	uint8_t dn_rm_spillblk[TXG_SIZE];	/* for removing spill blk */
325	uint16_t dn_next_bonuslen[TXG_SIZE];
326	uint32_t dn_next_blksz[TXG_SIZE];	/* next block size in bytes */
327	uint64_t dn_next_maxblkid[TXG_SIZE];	/* next maxblkid in bytes */
328
329	/* protected by dn_dbufs_mtx; declared here to fill 32-bit hole */
330	uint32_t dn_dbufs_count;	/* count of dn_dbufs */
331
332	/* protected by os_lock: */
333	multilist_node_t dn_dirty_link[TXG_SIZE]; /* next on dataset's dirty */
334
335	/* protected by dn_mtx: */
336	kmutex_t dn_mtx;
337	list_t dn_dirty_records[TXG_SIZE];
338	struct range_tree *dn_free_ranges[TXG_SIZE];
339	uint64_t dn_allocated_txg;
340	uint64_t dn_free_txg;
341	uint64_t dn_assigned_txg;
342	uint64_t dn_dirty_txg;			/* txg dnode was last dirtied */
343	kcondvar_t dn_notxholds;
344	kcondvar_t dn_nodnholds;
345	enum dnode_dirtycontext dn_dirtyctx;
346	const void *dn_dirtyctx_firstset;	/* dbg: contents meaningless */
347
348	/* protected by own devices */
349	zfs_refcount_t dn_tx_holds;
350	zfs_refcount_t dn_holds;
351
352	kmutex_t dn_dbufs_mtx;
353	/*
354	 * Descendent dbufs, ordered by dbuf_compare. Note that dn_dbufs
355	 * can contain multiple dbufs of the same (level, blkid) when a
356	 * dbuf is marked DB_EVICTING without being removed from
357	 * dn_dbufs. To maintain the avl invariant that there cannot be
358	 * duplicate entries, we order the dbufs by an arbitrary value -
359	 * their address in memory. This means that dn_dbufs cannot be used to
360	 * directly look up a dbuf. Instead, callers must use avl_walk, have
361	 * a reference to the dbuf, or look up a non-existent node with
362	 * db_state = DB_SEARCH (see dbuf_free_range for an example).
363	 */
364	avl_tree_t dn_dbufs;
365
366	/* protected by dn_struct_rwlock */
367	struct dmu_buf_impl *dn_bonus;	/* bonus buffer dbuf */
368
369	boolean_t dn_have_spill;	/* have spill or are spilling */
370
371	/* parent IO for current sync write */
372	zio_t *dn_zio;
373
374	/* used in syncing context */
375	uint64_t dn_oldused;	/* old phys used bytes */
376	uint64_t dn_oldflags;	/* old phys dn_flags */
377	uint64_t dn_olduid, dn_oldgid, dn_oldprojid;
378	uint64_t dn_newuid, dn_newgid, dn_newprojid;
379	int dn_id_flags;
380
381	/* holds prefetch structure */
382	struct zfetch	dn_zfetch;
383};
384
385/*
386 * Since AVL already has embedded element counter, use dn_dbufs_count
387 * only for dbufs not counted there (bonus buffers) and just add them.
388 */
389#define	DN_DBUFS_COUNT(dn)	((dn)->dn_dbufs_count + \
390    avl_numnodes(&(dn)->dn_dbufs))
391
392/*
393 * We use this (otherwise unused) bit to indicate if the value of
394 * dn_next_maxblkid[txgoff] is valid to use in dnode_sync().
395 */
396#define	DMU_NEXT_MAXBLKID_SET		(1ULL << 63)
397
398/*
399 * Adds a level of indirection between the dbuf and the dnode to avoid
400 * iterating descendent dbufs in dnode_move(). Handles are not allocated
401 * individually, but as an array of child dnodes in dnode_hold_impl().
402 */
403typedef struct dnode_handle {
404	/* Protects dnh_dnode from modification by dnode_move(). */
405	zrlock_t dnh_zrlock;
406	dnode_t *dnh_dnode;
407} dnode_handle_t;
408
409typedef struct dnode_children {
410	dmu_buf_user_t dnc_dbu;		/* User evict data */
411	size_t dnc_count;		/* number of children */
412	dnode_handle_t dnc_children[];	/* sized dynamically */
413} dnode_children_t;
414
415typedef struct free_range {
416	avl_node_t fr_node;
417	uint64_t fr_blkid;
418	uint64_t fr_nblks;
419} free_range_t;
420
421void dnode_special_open(struct objset *dd, dnode_phys_t *dnp,
422    uint64_t object, dnode_handle_t *dnh);
423void dnode_special_close(dnode_handle_t *dnh);
424
425void dnode_setbonuslen(dnode_t *dn, int newsize, dmu_tx_t *tx);
426void dnode_setbonus_type(dnode_t *dn, dmu_object_type_t, dmu_tx_t *tx);
427void dnode_rm_spill(dnode_t *dn, dmu_tx_t *tx);
428
429int dnode_hold(struct objset *dd, uint64_t object,
430    const void *ref, dnode_t **dnp);
431int dnode_hold_impl(struct objset *dd, uint64_t object, int flag, int dn_slots,
432    const void *ref, dnode_t **dnp);
433boolean_t dnode_add_ref(dnode_t *dn, const void *ref);
434void dnode_rele(dnode_t *dn, const void *ref);
435void dnode_rele_and_unlock(dnode_t *dn, const void *tag, boolean_t evicting);
436int dnode_try_claim(objset_t *os, uint64_t object, int slots);
437boolean_t dnode_is_dirty(dnode_t *dn);
438void dnode_setdirty(dnode_t *dn, dmu_tx_t *tx);
439void dnode_set_dirtyctx(dnode_t *dn, dmu_tx_t *tx, const void *tag);
440void dnode_sync(dnode_t *dn, dmu_tx_t *tx);
441void dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs,
442    dmu_object_type_t bonustype, int bonuslen, int dn_slots, dmu_tx_t *tx);
443void dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize,
444    dmu_object_type_t bonustype, int bonuslen, int dn_slots,
445    boolean_t keep_spill, dmu_tx_t *tx);
446void dnode_free(dnode_t *dn, dmu_tx_t *tx);
447void dnode_byteswap(dnode_phys_t *dnp);
448void dnode_buf_byteswap(void *buf, size_t size);
449void dnode_verify(dnode_t *dn);
450int dnode_set_nlevels(dnode_t *dn, int nlevels, dmu_tx_t *tx);
451int dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx);
452void dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx);
453void dnode_diduse_space(dnode_t *dn, int64_t space);
454void dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx,
455    boolean_t have_read, boolean_t force);
456uint64_t dnode_block_freed(dnode_t *dn, uint64_t blkid);
457void dnode_init(void);
458void dnode_fini(void);
459int dnode_next_offset(dnode_t *dn, int flags, uint64_t *off,
460    int minlvl, uint64_t blkfill, uint64_t txg);
461void dnode_evict_dbufs(dnode_t *dn);
462void dnode_evict_bonus(dnode_t *dn);
463void dnode_free_interior_slots(dnode_t *dn);
464
465#define	DNODE_IS_DIRTY(_dn)						\
466	((_dn)->dn_dirty_txg >= spa_syncing_txg((_dn)->dn_objset->os_spa))
467
468#define	DNODE_LEVEL_IS_CACHEABLE(_dn, _level)				\
469	((_dn)->dn_objset->os_primary_cache == ZFS_CACHE_ALL ||		\
470	(((_level) > 0 || DMU_OT_IS_METADATA((_dn)->dn_type)) &&	\
471	(_dn)->dn_objset->os_primary_cache == ZFS_CACHE_METADATA))
472
473/*
474 * Used for dnodestats kstat.
475 */
476typedef struct dnode_stats {
477	/*
478	 * Number of failed attempts to hold a meta dnode dbuf.
479	 */
480	kstat_named_t dnode_hold_dbuf_hold;
481	/*
482	 * Number of failed attempts to read a meta dnode dbuf.
483	 */
484	kstat_named_t dnode_hold_dbuf_read;
485	/*
486	 * Number of times dnode_hold(..., DNODE_MUST_BE_ALLOCATED) was able
487	 * to hold the requested object number which was allocated.  This is
488	 * the common case when looking up any allocated object number.
489	 */
490	kstat_named_t dnode_hold_alloc_hits;
491	/*
492	 * Number of times dnode_hold(..., DNODE_MUST_BE_ALLOCATED) was not
493	 * able to hold the request object number because it was not allocated.
494	 */
495	kstat_named_t dnode_hold_alloc_misses;
496	/*
497	 * Number of times dnode_hold(..., DNODE_MUST_BE_ALLOCATED) was not
498	 * able to hold the request object number because the object number
499	 * refers to an interior large dnode slot.
500	 */
501	kstat_named_t dnode_hold_alloc_interior;
502	/*
503	 * Number of times dnode_hold(..., DNODE_MUST_BE_ALLOCATED) needed
504	 * to retry acquiring slot zrl locks due to contention.
505	 */
506	kstat_named_t dnode_hold_alloc_lock_retry;
507	/*
508	 * Number of times dnode_hold(..., DNODE_MUST_BE_ALLOCATED) did not
509	 * need to create the dnode because another thread did so after
510	 * dropping the read lock but before acquiring the write lock.
511	 */
512	kstat_named_t dnode_hold_alloc_lock_misses;
513	/*
514	 * Number of times dnode_hold(..., DNODE_MUST_BE_ALLOCATED) found
515	 * a free dnode instantiated by dnode_create() but not yet allocated
516	 * by dnode_allocate().
517	 */
518	kstat_named_t dnode_hold_alloc_type_none;
519	/*
520	 * Number of times dnode_hold(..., DNODE_MUST_BE_FREE) was able
521	 * to hold the requested range of free dnode slots.
522	 */
523	kstat_named_t dnode_hold_free_hits;
524	/*
525	 * Number of times dnode_hold(..., DNODE_MUST_BE_FREE) was not
526	 * able to hold the requested range of free dnode slots because
527	 * at least one slot was allocated.
528	 */
529	kstat_named_t dnode_hold_free_misses;
530	/*
531	 * Number of times dnode_hold(..., DNODE_MUST_BE_FREE) was not
532	 * able to hold the requested range of free dnode slots because
533	 * after acquiring the zrl lock at least one slot was allocated.
534	 */
535	kstat_named_t dnode_hold_free_lock_misses;
536	/*
537	 * Number of times dnode_hold(..., DNODE_MUST_BE_FREE) needed
538	 * to retry acquiring slot zrl locks due to contention.
539	 */
540	kstat_named_t dnode_hold_free_lock_retry;
541	/*
542	 * Number of times dnode_hold(..., DNODE_MUST_BE_FREE) requested
543	 * a range of dnode slots which were held by another thread.
544	 */
545	kstat_named_t dnode_hold_free_refcount;
546	/*
547	 * Number of times dnode_hold(..., DNODE_MUST_BE_FREE) requested
548	 * a range of dnode slots which would overflow the dnode_phys_t.
549	 */
550	kstat_named_t dnode_hold_free_overflow;
551	/*
552	 * Number of times dnode_free_interior_slots() needed to retry
553	 * acquiring a slot zrl lock due to contention.
554	 */
555	kstat_named_t dnode_free_interior_lock_retry;
556	/*
557	 * Number of new dnodes allocated by dnode_allocate().
558	 */
559	kstat_named_t dnode_allocate;
560	/*
561	 * Number of dnodes re-allocated by dnode_reallocate().
562	 */
563	kstat_named_t dnode_reallocate;
564	/*
565	 * Number of meta dnode dbufs evicted.
566	 */
567	kstat_named_t dnode_buf_evict;
568	/*
569	 * Number of times dmu_object_alloc*() reached the end of the existing
570	 * object ID chunk and advanced to a new one.
571	 */
572	kstat_named_t dnode_alloc_next_chunk;
573	/*
574	 * Number of times multiple threads attempted to allocate a dnode
575	 * from the same block of free dnodes.
576	 */
577	kstat_named_t dnode_alloc_race;
578	/*
579	 * Number of times dmu_object_alloc*() was forced to advance to the
580	 * next meta dnode dbuf due to an error from  dmu_object_next().
581	 */
582	kstat_named_t dnode_alloc_next_block;
583	/*
584	 * Statistics for tracking dnodes which have been moved.
585	 */
586	kstat_named_t dnode_move_invalid;
587	kstat_named_t dnode_move_recheck1;
588	kstat_named_t dnode_move_recheck2;
589	kstat_named_t dnode_move_special;
590	kstat_named_t dnode_move_handle;
591	kstat_named_t dnode_move_rwlock;
592	kstat_named_t dnode_move_active;
593} dnode_stats_t;
594
595typedef struct dnode_sums {
596	wmsum_t dnode_hold_dbuf_hold;
597	wmsum_t dnode_hold_dbuf_read;
598	wmsum_t dnode_hold_alloc_hits;
599	wmsum_t dnode_hold_alloc_misses;
600	wmsum_t dnode_hold_alloc_interior;
601	wmsum_t dnode_hold_alloc_lock_retry;
602	wmsum_t dnode_hold_alloc_lock_misses;
603	wmsum_t dnode_hold_alloc_type_none;
604	wmsum_t dnode_hold_free_hits;
605	wmsum_t dnode_hold_free_misses;
606	wmsum_t dnode_hold_free_lock_misses;
607	wmsum_t dnode_hold_free_lock_retry;
608	wmsum_t dnode_hold_free_refcount;
609	wmsum_t dnode_hold_free_overflow;
610	wmsum_t dnode_free_interior_lock_retry;
611	wmsum_t dnode_allocate;
612	wmsum_t dnode_reallocate;
613	wmsum_t dnode_buf_evict;
614	wmsum_t dnode_alloc_next_chunk;
615	wmsum_t dnode_alloc_race;
616	wmsum_t dnode_alloc_next_block;
617	wmsum_t dnode_move_invalid;
618	wmsum_t dnode_move_recheck1;
619	wmsum_t dnode_move_recheck2;
620	wmsum_t dnode_move_special;
621	wmsum_t dnode_move_handle;
622	wmsum_t dnode_move_rwlock;
623	wmsum_t dnode_move_active;
624} dnode_sums_t;
625
626extern dnode_stats_t dnode_stats;
627extern dnode_sums_t dnode_sums;
628
629#define	DNODE_STAT_INCR(stat, val) \
630    wmsum_add(&dnode_sums.stat, (val))
631#define	DNODE_STAT_BUMP(stat) \
632    DNODE_STAT_INCR(stat, 1);
633
634#ifdef ZFS_DEBUG
635
636#define	dprintf_dnode(dn, fmt, ...) do { \
637	if (zfs_flags & ZFS_DEBUG_DPRINTF) { \
638	char __db_buf[32]; \
639	uint64_t __db_obj = (dn)->dn_object; \
640	if (__db_obj == DMU_META_DNODE_OBJECT) \
641		(void) strlcpy(__db_buf, "mdn", sizeof (__db_buf));	\
642	else \
643		(void) snprintf(__db_buf, sizeof (__db_buf), "%lld", \
644		    (u_longlong_t)__db_obj);\
645	dprintf_ds((dn)->dn_objset->os_dsl_dataset, "obj=%s " fmt, \
646	    __db_buf, __VA_ARGS__); \
647	} \
648} while (0)
649
650#define	DNODE_VERIFY(dn)		dnode_verify(dn)
651#define	FREE_VERIFY(db, start, end, tx)	free_verify(db, start, end, tx)
652
653#else
654
655#define	dprintf_dnode(db, fmt, ...)
656#define	DNODE_VERIFY(dn)		((void) sizeof ((uintptr_t)(dn)))
657#define	FREE_VERIFY(db, start, end, tx)
658
659#endif
660
661#ifdef	__cplusplus
662}
663#endif
664
665#endif	/* _SYS_DNODE_H */
666