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.
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.
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]
22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright (c) 2012, 2015 by Delphix. All rights reserved.
24 * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
25 * Copyright (c) 2014 Integros [integros.com]
28 #include <sys/zfs_context.h>
30 #include <sys/dnode.h>
32 #include <sys/dmu_impl.h>
33 #include <sys/dmu_tx.h>
34 #include <sys/dmu_objset.h>
35 #include <sys/dsl_dir.h>
36 #include <sys/dsl_dataset.h>
39 #include <sys/dmu_zfetch.h>
40 #include <sys/range_tree.h>
42 static kmem_cache_t
*dnode_cache
;
44 * Define DNODE_STATS to turn on statistic gathering. By default, it is only
45 * turned on when DEBUG is also defined.
52 #define DNODE_STAT_ADD(stat) ((stat)++)
54 #define DNODE_STAT_ADD(stat) /* nothing */
55 #endif /* DNODE_STATS */
57 static dnode_phys_t dnode_phys_zero
;
59 int zfs_default_bs
= SPA_MINBLOCKSHIFT
;
60 int zfs_default_ibs
= DN_MAX_INDBLKSHIFT
;
62 static kmem_cbrc_t
dnode_move(void *, void *, size_t, void *);
65 dbuf_compare(const void *x1
, const void *x2
)
67 const dmu_buf_impl_t
*d1
= x1
;
68 const dmu_buf_impl_t
*d2
= x2
;
70 if (d1
->db_level
< d2
->db_level
) {
73 if (d1
->db_level
> d2
->db_level
) {
77 if (d1
->db_blkid
< d2
->db_blkid
) {
80 if (d1
->db_blkid
> d2
->db_blkid
) {
84 if (d1
->db_state
== DB_SEARCH
) {
85 ASSERT3S(d2
->db_state
, !=, DB_SEARCH
);
87 } else if (d2
->db_state
== DB_SEARCH
) {
88 ASSERT3S(d1
->db_state
, !=, DB_SEARCH
);
92 if ((uintptr_t)d1
< (uintptr_t)d2
) {
95 if ((uintptr_t)d1
> (uintptr_t)d2
) {
103 dnode_cons(void *arg
, void *unused
, int kmflag
)
108 rw_init(&dn
->dn_struct_rwlock
, NULL
, RW_DEFAULT
, NULL
);
109 mutex_init(&dn
->dn_mtx
, NULL
, MUTEX_DEFAULT
, NULL
);
110 mutex_init(&dn
->dn_dbufs_mtx
, NULL
, MUTEX_DEFAULT
, NULL
);
111 cv_init(&dn
->dn_notxholds
, NULL
, CV_DEFAULT
, NULL
);
114 * Every dbuf has a reference, and dropping a tracked reference is
115 * O(number of references), so don't track dn_holds.
117 refcount_create_untracked(&dn
->dn_holds
);
118 refcount_create(&dn
->dn_tx_holds
);
119 list_link_init(&dn
->dn_link
);
121 bzero(&dn
->dn_next_nblkptr
[0], sizeof (dn
->dn_next_nblkptr
));
122 bzero(&dn
->dn_next_nlevels
[0], sizeof (dn
->dn_next_nlevels
));
123 bzero(&dn
->dn_next_indblkshift
[0], sizeof (dn
->dn_next_indblkshift
));
124 bzero(&dn
->dn_next_bonustype
[0], sizeof (dn
->dn_next_bonustype
));
125 bzero(&dn
->dn_rm_spillblk
[0], sizeof (dn
->dn_rm_spillblk
));
126 bzero(&dn
->dn_next_bonuslen
[0], sizeof (dn
->dn_next_bonuslen
));
127 bzero(&dn
->dn_next_blksz
[0], sizeof (dn
->dn_next_blksz
));
129 for (i
= 0; i
< TXG_SIZE
; i
++) {
130 list_link_init(&dn
->dn_dirty_link
[i
]);
131 dn
->dn_free_ranges
[i
] = NULL
;
132 list_create(&dn
->dn_dirty_records
[i
],
133 sizeof (dbuf_dirty_record_t
),
134 offsetof(dbuf_dirty_record_t
, dr_dirty_node
));
137 dn
->dn_allocated_txg
= 0;
139 dn
->dn_assigned_txg
= 0;
141 dn
->dn_dirtyctx_firstset
= NULL
;
143 dn
->dn_have_spill
= B_FALSE
;
153 dn
->dn_dbufs_count
= 0;
154 dn
->dn_unlisted_l0_blkid
= 0;
155 avl_create(&dn
->dn_dbufs
, dbuf_compare
, sizeof (dmu_buf_impl_t
),
156 offsetof(dmu_buf_impl_t
, db_link
));
164 dnode_dest(void *arg
, void *unused
)
169 rw_destroy(&dn
->dn_struct_rwlock
);
170 mutex_destroy(&dn
->dn_mtx
);
171 mutex_destroy(&dn
->dn_dbufs_mtx
);
172 cv_destroy(&dn
->dn_notxholds
);
173 refcount_destroy(&dn
->dn_holds
);
174 refcount_destroy(&dn
->dn_tx_holds
);
175 ASSERT(!list_link_active(&dn
->dn_link
));
177 for (i
= 0; i
< TXG_SIZE
; i
++) {
178 ASSERT(!list_link_active(&dn
->dn_dirty_link
[i
]));
179 ASSERT3P(dn
->dn_free_ranges
[i
], ==, NULL
);
180 list_destroy(&dn
->dn_dirty_records
[i
]);
181 ASSERT0(dn
->dn_next_nblkptr
[i
]);
182 ASSERT0(dn
->dn_next_nlevels
[i
]);
183 ASSERT0(dn
->dn_next_indblkshift
[i
]);
184 ASSERT0(dn
->dn_next_bonustype
[i
]);
185 ASSERT0(dn
->dn_rm_spillblk
[i
]);
186 ASSERT0(dn
->dn_next_bonuslen
[i
]);
187 ASSERT0(dn
->dn_next_blksz
[i
]);
190 ASSERT0(dn
->dn_allocated_txg
);
191 ASSERT0(dn
->dn_free_txg
);
192 ASSERT0(dn
->dn_assigned_txg
);
193 ASSERT0(dn
->dn_dirtyctx
);
194 ASSERT3P(dn
->dn_dirtyctx_firstset
, ==, NULL
);
195 ASSERT3P(dn
->dn_bonus
, ==, NULL
);
196 ASSERT(!dn
->dn_have_spill
);
197 ASSERT3P(dn
->dn_zio
, ==, NULL
);
198 ASSERT0(dn
->dn_oldused
);
199 ASSERT0(dn
->dn_oldflags
);
200 ASSERT0(dn
->dn_olduid
);
201 ASSERT0(dn
->dn_oldgid
);
202 ASSERT0(dn
->dn_newuid
);
203 ASSERT0(dn
->dn_newgid
);
204 ASSERT0(dn
->dn_id_flags
);
206 ASSERT0(dn
->dn_dbufs_count
);
207 ASSERT0(dn
->dn_unlisted_l0_blkid
);
208 avl_destroy(&dn
->dn_dbufs
);
214 ASSERT(dnode_cache
== NULL
);
215 dnode_cache
= kmem_cache_create("dnode_t",
217 0, dnode_cons
, dnode_dest
, NULL
, NULL
, NULL
, 0);
218 kmem_cache_set_move(dnode_cache
, dnode_move
);
224 kmem_cache_destroy(dnode_cache
);
231 dnode_verify(dnode_t
*dn
)
233 int drop_struct_lock
= FALSE
;
236 ASSERT(dn
->dn_objset
);
237 ASSERT(dn
->dn_handle
->dnh_dnode
== dn
);
239 ASSERT(DMU_OT_IS_VALID(dn
->dn_phys
->dn_type
));
241 if (!(zfs_flags
& ZFS_DEBUG_DNODE_VERIFY
))
244 if (!RW_WRITE_HELD(&dn
->dn_struct_rwlock
)) {
245 rw_enter(&dn
->dn_struct_rwlock
, RW_READER
);
246 drop_struct_lock
= TRUE
;
248 if (dn
->dn_phys
->dn_type
!= DMU_OT_NONE
|| dn
->dn_allocated_txg
!= 0) {
250 ASSERT3U(dn
->dn_indblkshift
, >=, 0);
251 ASSERT3U(dn
->dn_indblkshift
, <=, SPA_MAXBLOCKSHIFT
);
252 if (dn
->dn_datablkshift
) {
253 ASSERT3U(dn
->dn_datablkshift
, >=, SPA_MINBLOCKSHIFT
);
254 ASSERT3U(dn
->dn_datablkshift
, <=, SPA_MAXBLOCKSHIFT
);
255 ASSERT3U(1<<dn
->dn_datablkshift
, ==, dn
->dn_datablksz
);
257 ASSERT3U(dn
->dn_nlevels
, <=, 30);
258 ASSERT(DMU_OT_IS_VALID(dn
->dn_type
));
259 ASSERT3U(dn
->dn_nblkptr
, >=, 1);
260 ASSERT3U(dn
->dn_nblkptr
, <=, DN_MAX_NBLKPTR
);
261 ASSERT3U(dn
->dn_bonuslen
, <=, DN_MAX_BONUSLEN
);
262 ASSERT3U(dn
->dn_datablksz
, ==,
263 dn
->dn_datablkszsec
<< SPA_MINBLOCKSHIFT
);
264 ASSERT3U(ISP2(dn
->dn_datablksz
), ==, dn
->dn_datablkshift
!= 0);
265 ASSERT3U((dn
->dn_nblkptr
- 1) * sizeof (blkptr_t
) +
266 dn
->dn_bonuslen
, <=, DN_MAX_BONUSLEN
);
267 for (i
= 0; i
< TXG_SIZE
; i
++) {
268 ASSERT3U(dn
->dn_next_nlevels
[i
], <=, dn
->dn_nlevels
);
271 if (dn
->dn_phys
->dn_type
!= DMU_OT_NONE
)
272 ASSERT3U(dn
->dn_phys
->dn_nlevels
, <=, dn
->dn_nlevels
);
273 ASSERT(DMU_OBJECT_IS_SPECIAL(dn
->dn_object
) || dn
->dn_dbuf
!= NULL
);
274 if (dn
->dn_dbuf
!= NULL
) {
275 ASSERT3P(dn
->dn_phys
, ==,
276 (dnode_phys_t
*)dn
->dn_dbuf
->db
.db_data
+
277 (dn
->dn_object
% (dn
->dn_dbuf
->db
.db_size
>> DNODE_SHIFT
)));
279 if (drop_struct_lock
)
280 rw_exit(&dn
->dn_struct_rwlock
);
285 dnode_byteswap(dnode_phys_t
*dnp
)
287 uint64_t *buf64
= (void*)&dnp
->dn_blkptr
;
290 if (dnp
->dn_type
== DMU_OT_NONE
) {
291 bzero(dnp
, sizeof (dnode_phys_t
));
295 dnp
->dn_datablkszsec
= BSWAP_16(dnp
->dn_datablkszsec
);
296 dnp
->dn_bonuslen
= BSWAP_16(dnp
->dn_bonuslen
);
297 dnp
->dn_maxblkid
= BSWAP_64(dnp
->dn_maxblkid
);
298 dnp
->dn_used
= BSWAP_64(dnp
->dn_used
);
301 * dn_nblkptr is only one byte, so it's OK to read it in either
302 * byte order. We can't read dn_bouslen.
304 ASSERT(dnp
->dn_indblkshift
<= SPA_MAXBLOCKSHIFT
);
305 ASSERT(dnp
->dn_nblkptr
<= DN_MAX_NBLKPTR
);
306 for (i
= 0; i
< dnp
->dn_nblkptr
* sizeof (blkptr_t
)/8; i
++)
307 buf64
[i
] = BSWAP_64(buf64
[i
]);
310 * OK to check dn_bonuslen for zero, because it won't matter if
311 * we have the wrong byte order. This is necessary because the
312 * dnode dnode is smaller than a regular dnode.
314 if (dnp
->dn_bonuslen
!= 0) {
316 * Note that the bonus length calculated here may be
317 * longer than the actual bonus buffer. This is because
318 * we always put the bonus buffer after the last block
319 * pointer (instead of packing it against the end of the
322 int off
= (dnp
->dn_nblkptr
-1) * sizeof (blkptr_t
);
323 size_t len
= DN_MAX_BONUSLEN
- off
;
324 ASSERT(DMU_OT_IS_VALID(dnp
->dn_bonustype
));
325 dmu_object_byteswap_t byteswap
=
326 DMU_OT_BYTESWAP(dnp
->dn_bonustype
);
327 dmu_ot_byteswap
[byteswap
].ob_func(dnp
->dn_bonus
+ off
, len
);
330 /* Swap SPILL block if we have one */
331 if (dnp
->dn_flags
& DNODE_FLAG_SPILL_BLKPTR
)
332 byteswap_uint64_array(&dnp
->dn_spill
, sizeof (blkptr_t
));
337 dnode_buf_byteswap(void *vbuf
, size_t size
)
339 dnode_phys_t
*buf
= vbuf
;
342 ASSERT3U(sizeof (dnode_phys_t
), ==, (1<<DNODE_SHIFT
));
343 ASSERT((size
& (sizeof (dnode_phys_t
)-1)) == 0);
345 size
>>= DNODE_SHIFT
;
346 for (i
= 0; i
< size
; i
++) {
353 dnode_setbonuslen(dnode_t
*dn
, int newsize
, dmu_tx_t
*tx
)
355 ASSERT3U(refcount_count(&dn
->dn_holds
), >=, 1);
357 dnode_setdirty(dn
, tx
);
358 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
359 ASSERT3U(newsize
, <=, DN_MAX_BONUSLEN
-
360 (dn
->dn_nblkptr
-1) * sizeof (blkptr_t
));
361 dn
->dn_bonuslen
= newsize
;
363 dn
->dn_next_bonuslen
[tx
->tx_txg
& TXG_MASK
] = DN_ZERO_BONUSLEN
;
365 dn
->dn_next_bonuslen
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_bonuslen
;
366 rw_exit(&dn
->dn_struct_rwlock
);
370 dnode_setbonus_type(dnode_t
*dn
, dmu_object_type_t newtype
, dmu_tx_t
*tx
)
372 ASSERT3U(refcount_count(&dn
->dn_holds
), >=, 1);
373 dnode_setdirty(dn
, tx
);
374 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
375 dn
->dn_bonustype
= newtype
;
376 dn
->dn_next_bonustype
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_bonustype
;
377 rw_exit(&dn
->dn_struct_rwlock
);
381 dnode_rm_spill(dnode_t
*dn
, dmu_tx_t
*tx
)
383 ASSERT3U(refcount_count(&dn
->dn_holds
), >=, 1);
384 ASSERT(RW_WRITE_HELD(&dn
->dn_struct_rwlock
));
385 dnode_setdirty(dn
, tx
);
386 dn
->dn_rm_spillblk
[tx
->tx_txg
&TXG_MASK
] = DN_KILL_SPILLBLK
;
387 dn
->dn_have_spill
= B_FALSE
;
391 dnode_setdblksz(dnode_t
*dn
, int size
)
393 ASSERT0(P2PHASE(size
, SPA_MINBLOCKSIZE
));
394 ASSERT3U(size
, <=, SPA_MAXBLOCKSIZE
);
395 ASSERT3U(size
, >=, SPA_MINBLOCKSIZE
);
396 ASSERT3U(size
>> SPA_MINBLOCKSHIFT
, <,
397 1<<(sizeof (dn
->dn_phys
->dn_datablkszsec
) * 8));
398 dn
->dn_datablksz
= size
;
399 dn
->dn_datablkszsec
= size
>> SPA_MINBLOCKSHIFT
;
400 dn
->dn_datablkshift
= ISP2(size
) ? highbit64(size
- 1) : 0;
404 dnode_create(objset_t
*os
, dnode_phys_t
*dnp
, dmu_buf_impl_t
*db
,
405 uint64_t object
, dnode_handle_t
*dnh
)
409 dn
= kmem_cache_alloc(dnode_cache
, KM_SLEEP
);
410 ASSERT(!POINTER_IS_VALID(dn
->dn_objset
));
414 * Defer setting dn_objset until the dnode is ready to be a candidate
415 * for the dnode_move() callback.
417 dn
->dn_object
= object
;
422 if (dnp
->dn_datablkszsec
) {
423 dnode_setdblksz(dn
, dnp
->dn_datablkszsec
<< SPA_MINBLOCKSHIFT
);
425 dn
->dn_datablksz
= 0;
426 dn
->dn_datablkszsec
= 0;
427 dn
->dn_datablkshift
= 0;
429 dn
->dn_indblkshift
= dnp
->dn_indblkshift
;
430 dn
->dn_nlevels
= dnp
->dn_nlevels
;
431 dn
->dn_type
= dnp
->dn_type
;
432 dn
->dn_nblkptr
= dnp
->dn_nblkptr
;
433 dn
->dn_checksum
= dnp
->dn_checksum
;
434 dn
->dn_compress
= dnp
->dn_compress
;
435 dn
->dn_bonustype
= dnp
->dn_bonustype
;
436 dn
->dn_bonuslen
= dnp
->dn_bonuslen
;
437 dn
->dn_maxblkid
= dnp
->dn_maxblkid
;
438 dn
->dn_have_spill
= ((dnp
->dn_flags
& DNODE_FLAG_SPILL_BLKPTR
) != 0);
441 dmu_zfetch_init(&dn
->dn_zfetch
, dn
);
443 ASSERT(DMU_OT_IS_VALID(dn
->dn_phys
->dn_type
));
445 mutex_enter(&os
->os_lock
);
446 if (dnh
->dnh_dnode
!= NULL
) {
447 /* Lost the allocation race. */
448 mutex_exit(&os
->os_lock
);
449 kmem_cache_free(dnode_cache
, dn
);
450 return (dnh
->dnh_dnode
);
454 * Exclude special dnodes from os_dnodes so an empty os_dnodes
455 * signifies that the special dnodes have no references from
456 * their children (the entries in os_dnodes). This allows
457 * dnode_destroy() to easily determine if the last child has
458 * been removed and then complete eviction of the objset.
460 if (!DMU_OBJECT_IS_SPECIAL(object
))
461 list_insert_head(&os
->os_dnodes
, dn
);
465 * Everything else must be valid before assigning dn_objset
466 * makes the dnode eligible for dnode_move().
471 mutex_exit(&os
->os_lock
);
473 arc_space_consume(sizeof (dnode_t
), ARC_SPACE_OTHER
);
478 * Caller must be holding the dnode handle, which is released upon return.
481 dnode_destroy(dnode_t
*dn
)
483 objset_t
*os
= dn
->dn_objset
;
484 boolean_t complete_os_eviction
= B_FALSE
;
486 ASSERT((dn
->dn_id_flags
& DN_ID_NEW_EXIST
) == 0);
488 mutex_enter(&os
->os_lock
);
489 POINTER_INVALIDATE(&dn
->dn_objset
);
490 if (!DMU_OBJECT_IS_SPECIAL(dn
->dn_object
)) {
491 list_remove(&os
->os_dnodes
, dn
);
492 complete_os_eviction
=
493 list_is_empty(&os
->os_dnodes
) &&
494 list_link_active(&os
->os_evicting_node
);
496 mutex_exit(&os
->os_lock
);
498 /* the dnode can no longer move, so we can release the handle */
499 zrl_remove(&dn
->dn_handle
->dnh_zrlock
);
501 dn
->dn_allocated_txg
= 0;
503 dn
->dn_assigned_txg
= 0;
506 if (dn
->dn_dirtyctx_firstset
!= NULL
) {
507 kmem_free(dn
->dn_dirtyctx_firstset
, 1);
508 dn
->dn_dirtyctx_firstset
= NULL
;
510 if (dn
->dn_bonus
!= NULL
) {
511 mutex_enter(&dn
->dn_bonus
->db_mtx
);
512 dbuf_evict(dn
->dn_bonus
);
517 dn
->dn_have_spill
= B_FALSE
;
525 dn
->dn_unlisted_l0_blkid
= 0;
527 dmu_zfetch_fini(&dn
->dn_zfetch
);
528 kmem_cache_free(dnode_cache
, dn
);
529 arc_space_return(sizeof (dnode_t
), ARC_SPACE_OTHER
);
531 if (complete_os_eviction
)
532 dmu_objset_evict_done(os
);
536 dnode_allocate(dnode_t
*dn
, dmu_object_type_t ot
, int blocksize
, int ibs
,
537 dmu_object_type_t bonustype
, int bonuslen
, dmu_tx_t
*tx
)
541 ASSERT3U(blocksize
, <=,
542 spa_maxblocksize(dmu_objset_spa(dn
->dn_objset
)));
544 blocksize
= 1 << zfs_default_bs
;
546 blocksize
= P2ROUNDUP(blocksize
, SPA_MINBLOCKSIZE
);
549 ibs
= zfs_default_ibs
;
551 ibs
= MIN(MAX(ibs
, DN_MIN_INDBLKSHIFT
), DN_MAX_INDBLKSHIFT
);
553 dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d\n", dn
->dn_objset
,
554 dn
->dn_object
, tx
->tx_txg
, blocksize
, ibs
);
556 ASSERT(dn
->dn_type
== DMU_OT_NONE
);
557 ASSERT(bcmp(dn
->dn_phys
, &dnode_phys_zero
, sizeof (dnode_phys_t
)) == 0);
558 ASSERT(dn
->dn_phys
->dn_type
== DMU_OT_NONE
);
559 ASSERT(ot
!= DMU_OT_NONE
);
560 ASSERT(DMU_OT_IS_VALID(ot
));
561 ASSERT((bonustype
== DMU_OT_NONE
&& bonuslen
== 0) ||
562 (bonustype
== DMU_OT_SA
&& bonuslen
== 0) ||
563 (bonustype
!= DMU_OT_NONE
&& bonuslen
!= 0));
564 ASSERT(DMU_OT_IS_VALID(bonustype
));
565 ASSERT3U(bonuslen
, <=, DN_MAX_BONUSLEN
);
566 ASSERT(dn
->dn_type
== DMU_OT_NONE
);
567 ASSERT0(dn
->dn_maxblkid
);
568 ASSERT0(dn
->dn_allocated_txg
);
569 ASSERT0(dn
->dn_assigned_txg
);
570 ASSERT(refcount_is_zero(&dn
->dn_tx_holds
));
571 ASSERT3U(refcount_count(&dn
->dn_holds
), <=, 1);
572 ASSERT(avl_is_empty(&dn
->dn_dbufs
));
574 for (i
= 0; i
< TXG_SIZE
; i
++) {
575 ASSERT0(dn
->dn_next_nblkptr
[i
]);
576 ASSERT0(dn
->dn_next_nlevels
[i
]);
577 ASSERT0(dn
->dn_next_indblkshift
[i
]);
578 ASSERT0(dn
->dn_next_bonuslen
[i
]);
579 ASSERT0(dn
->dn_next_bonustype
[i
]);
580 ASSERT0(dn
->dn_rm_spillblk
[i
]);
581 ASSERT0(dn
->dn_next_blksz
[i
]);
582 ASSERT(!list_link_active(&dn
->dn_dirty_link
[i
]));
583 ASSERT3P(list_head(&dn
->dn_dirty_records
[i
]), ==, NULL
);
584 ASSERT3P(dn
->dn_free_ranges
[i
], ==, NULL
);
588 dnode_setdblksz(dn
, blocksize
);
589 dn
->dn_indblkshift
= ibs
;
591 if (bonustype
== DMU_OT_SA
) /* Maximize bonus space for SA */
595 ((DN_MAX_BONUSLEN
- bonuslen
) >> SPA_BLKPTRSHIFT
);
596 dn
->dn_bonustype
= bonustype
;
597 dn
->dn_bonuslen
= bonuslen
;
598 dn
->dn_checksum
= ZIO_CHECKSUM_INHERIT
;
599 dn
->dn_compress
= ZIO_COMPRESS_INHERIT
;
603 if (dn
->dn_dirtyctx_firstset
) {
604 kmem_free(dn
->dn_dirtyctx_firstset
, 1);
605 dn
->dn_dirtyctx_firstset
= NULL
;
608 dn
->dn_allocated_txg
= tx
->tx_txg
;
611 dnode_setdirty(dn
, tx
);
612 dn
->dn_next_indblkshift
[tx
->tx_txg
& TXG_MASK
] = ibs
;
613 dn
->dn_next_bonuslen
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_bonuslen
;
614 dn
->dn_next_bonustype
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_bonustype
;
615 dn
->dn_next_blksz
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_datablksz
;
619 dnode_reallocate(dnode_t
*dn
, dmu_object_type_t ot
, int blocksize
,
620 dmu_object_type_t bonustype
, int bonuslen
, dmu_tx_t
*tx
)
624 ASSERT3U(blocksize
, >=, SPA_MINBLOCKSIZE
);
625 ASSERT3U(blocksize
, <=,
626 spa_maxblocksize(dmu_objset_spa(dn
->dn_objset
)));
627 ASSERT0(blocksize
% SPA_MINBLOCKSIZE
);
628 ASSERT(dn
->dn_object
!= DMU_META_DNODE_OBJECT
|| dmu_tx_private_ok(tx
));
629 ASSERT(tx
->tx_txg
!= 0);
630 ASSERT((bonustype
== DMU_OT_NONE
&& bonuslen
== 0) ||
631 (bonustype
!= DMU_OT_NONE
&& bonuslen
!= 0) ||
632 (bonustype
== DMU_OT_SA
&& bonuslen
== 0));
633 ASSERT(DMU_OT_IS_VALID(bonustype
));
634 ASSERT3U(bonuslen
, <=, DN_MAX_BONUSLEN
);
636 /* clean up any unreferenced dbufs */
637 dnode_evict_dbufs(dn
);
641 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
642 dnode_setdirty(dn
, tx
);
643 if (dn
->dn_datablksz
!= blocksize
) {
644 /* change blocksize */
645 ASSERT(dn
->dn_maxblkid
== 0 &&
646 (BP_IS_HOLE(&dn
->dn_phys
->dn_blkptr
[0]) ||
647 dnode_block_freed(dn
, 0)));
648 dnode_setdblksz(dn
, blocksize
);
649 dn
->dn_next_blksz
[tx
->tx_txg
&TXG_MASK
] = blocksize
;
651 if (dn
->dn_bonuslen
!= bonuslen
)
652 dn
->dn_next_bonuslen
[tx
->tx_txg
&TXG_MASK
] = bonuslen
;
654 if (bonustype
== DMU_OT_SA
) /* Maximize bonus space for SA */
657 nblkptr
= 1 + ((DN_MAX_BONUSLEN
- bonuslen
) >> SPA_BLKPTRSHIFT
);
658 if (dn
->dn_bonustype
!= bonustype
)
659 dn
->dn_next_bonustype
[tx
->tx_txg
&TXG_MASK
] = bonustype
;
660 if (dn
->dn_nblkptr
!= nblkptr
)
661 dn
->dn_next_nblkptr
[tx
->tx_txg
&TXG_MASK
] = nblkptr
;
662 if (dn
->dn_phys
->dn_flags
& DNODE_FLAG_SPILL_BLKPTR
) {
663 dbuf_rm_spill(dn
, tx
);
664 dnode_rm_spill(dn
, tx
);
666 rw_exit(&dn
->dn_struct_rwlock
);
671 /* change bonus size and type */
672 mutex_enter(&dn
->dn_mtx
);
673 dn
->dn_bonustype
= bonustype
;
674 dn
->dn_bonuslen
= bonuslen
;
675 dn
->dn_nblkptr
= nblkptr
;
676 dn
->dn_checksum
= ZIO_CHECKSUM_INHERIT
;
677 dn
->dn_compress
= ZIO_COMPRESS_INHERIT
;
678 ASSERT3U(dn
->dn_nblkptr
, <=, DN_MAX_NBLKPTR
);
680 /* fix up the bonus db_size */
682 dn
->dn_bonus
->db
.db_size
=
683 DN_MAX_BONUSLEN
- (dn
->dn_nblkptr
-1) * sizeof (blkptr_t
);
684 ASSERT(dn
->dn_bonuslen
<= dn
->dn_bonus
->db
.db_size
);
687 dn
->dn_allocated_txg
= tx
->tx_txg
;
688 mutex_exit(&dn
->dn_mtx
);
693 uint64_t dms_dnode_invalid
;
694 uint64_t dms_dnode_recheck1
;
695 uint64_t dms_dnode_recheck2
;
696 uint64_t dms_dnode_special
;
697 uint64_t dms_dnode_handle
;
698 uint64_t dms_dnode_rwlock
;
699 uint64_t dms_dnode_active
;
701 #endif /* DNODE_STATS */
704 dnode_move_impl(dnode_t
*odn
, dnode_t
*ndn
)
708 ASSERT(!RW_LOCK_HELD(&odn
->dn_struct_rwlock
));
709 ASSERT(MUTEX_NOT_HELD(&odn
->dn_mtx
));
710 ASSERT(MUTEX_NOT_HELD(&odn
->dn_dbufs_mtx
));
711 ASSERT(!RW_LOCK_HELD(&odn
->dn_zfetch
.zf_rwlock
));
714 ndn
->dn_objset
= odn
->dn_objset
;
715 ndn
->dn_object
= odn
->dn_object
;
716 ndn
->dn_dbuf
= odn
->dn_dbuf
;
717 ndn
->dn_handle
= odn
->dn_handle
;
718 ndn
->dn_phys
= odn
->dn_phys
;
719 ndn
->dn_type
= odn
->dn_type
;
720 ndn
->dn_bonuslen
= odn
->dn_bonuslen
;
721 ndn
->dn_bonustype
= odn
->dn_bonustype
;
722 ndn
->dn_nblkptr
= odn
->dn_nblkptr
;
723 ndn
->dn_checksum
= odn
->dn_checksum
;
724 ndn
->dn_compress
= odn
->dn_compress
;
725 ndn
->dn_nlevels
= odn
->dn_nlevels
;
726 ndn
->dn_indblkshift
= odn
->dn_indblkshift
;
727 ndn
->dn_datablkshift
= odn
->dn_datablkshift
;
728 ndn
->dn_datablkszsec
= odn
->dn_datablkszsec
;
729 ndn
->dn_datablksz
= odn
->dn_datablksz
;
730 ndn
->dn_maxblkid
= odn
->dn_maxblkid
;
731 bcopy(&odn
->dn_next_nblkptr
[0], &ndn
->dn_next_nblkptr
[0],
732 sizeof (odn
->dn_next_nblkptr
));
733 bcopy(&odn
->dn_next_nlevels
[0], &ndn
->dn_next_nlevels
[0],
734 sizeof (odn
->dn_next_nlevels
));
735 bcopy(&odn
->dn_next_indblkshift
[0], &ndn
->dn_next_indblkshift
[0],
736 sizeof (odn
->dn_next_indblkshift
));
737 bcopy(&odn
->dn_next_bonustype
[0], &ndn
->dn_next_bonustype
[0],
738 sizeof (odn
->dn_next_bonustype
));
739 bcopy(&odn
->dn_rm_spillblk
[0], &ndn
->dn_rm_spillblk
[0],
740 sizeof (odn
->dn_rm_spillblk
));
741 bcopy(&odn
->dn_next_bonuslen
[0], &ndn
->dn_next_bonuslen
[0],
742 sizeof (odn
->dn_next_bonuslen
));
743 bcopy(&odn
->dn_next_blksz
[0], &ndn
->dn_next_blksz
[0],
744 sizeof (odn
->dn_next_blksz
));
745 for (i
= 0; i
< TXG_SIZE
; i
++) {
746 list_move_tail(&ndn
->dn_dirty_records
[i
],
747 &odn
->dn_dirty_records
[i
]);
749 bcopy(&odn
->dn_free_ranges
[0], &ndn
->dn_free_ranges
[0],
750 sizeof (odn
->dn_free_ranges
));
751 ndn
->dn_allocated_txg
= odn
->dn_allocated_txg
;
752 ndn
->dn_free_txg
= odn
->dn_free_txg
;
753 ndn
->dn_assigned_txg
= odn
->dn_assigned_txg
;
754 ndn
->dn_dirtyctx
= odn
->dn_dirtyctx
;
755 ndn
->dn_dirtyctx_firstset
= odn
->dn_dirtyctx_firstset
;
756 ASSERT(refcount_count(&odn
->dn_tx_holds
) == 0);
757 refcount_transfer(&ndn
->dn_holds
, &odn
->dn_holds
);
758 ASSERT(avl_is_empty(&ndn
->dn_dbufs
));
759 avl_swap(&ndn
->dn_dbufs
, &odn
->dn_dbufs
);
760 ndn
->dn_dbufs_count
= odn
->dn_dbufs_count
;
761 ndn
->dn_unlisted_l0_blkid
= odn
->dn_unlisted_l0_blkid
;
762 ndn
->dn_bonus
= odn
->dn_bonus
;
763 ndn
->dn_have_spill
= odn
->dn_have_spill
;
764 ndn
->dn_zio
= odn
->dn_zio
;
765 ndn
->dn_oldused
= odn
->dn_oldused
;
766 ndn
->dn_oldflags
= odn
->dn_oldflags
;
767 ndn
->dn_olduid
= odn
->dn_olduid
;
768 ndn
->dn_oldgid
= odn
->dn_oldgid
;
769 ndn
->dn_newuid
= odn
->dn_newuid
;
770 ndn
->dn_newgid
= odn
->dn_newgid
;
771 ndn
->dn_id_flags
= odn
->dn_id_flags
;
772 dmu_zfetch_init(&ndn
->dn_zfetch
, NULL
);
773 list_move_tail(&ndn
->dn_zfetch
.zf_stream
, &odn
->dn_zfetch
.zf_stream
);
774 ndn
->dn_zfetch
.zf_dnode
= odn
->dn_zfetch
.zf_dnode
;
777 * Update back pointers. Updating the handle fixes the back pointer of
778 * every descendant dbuf as well as the bonus dbuf.
780 ASSERT(ndn
->dn_handle
->dnh_dnode
== odn
);
781 ndn
->dn_handle
->dnh_dnode
= ndn
;
782 if (ndn
->dn_zfetch
.zf_dnode
== odn
) {
783 ndn
->dn_zfetch
.zf_dnode
= ndn
;
787 * Invalidate the original dnode by clearing all of its back pointers.
790 odn
->dn_handle
= NULL
;
791 avl_create(&odn
->dn_dbufs
, dbuf_compare
, sizeof (dmu_buf_impl_t
),
792 offsetof(dmu_buf_impl_t
, db_link
));
793 odn
->dn_dbufs_count
= 0;
794 odn
->dn_unlisted_l0_blkid
= 0;
795 odn
->dn_bonus
= NULL
;
796 odn
->dn_zfetch
.zf_dnode
= NULL
;
799 * Set the low bit of the objset pointer to ensure that dnode_move()
800 * recognizes the dnode as invalid in any subsequent callback.
802 POINTER_INVALIDATE(&odn
->dn_objset
);
805 * Satisfy the destructor.
807 for (i
= 0; i
< TXG_SIZE
; i
++) {
808 list_create(&odn
->dn_dirty_records
[i
],
809 sizeof (dbuf_dirty_record_t
),
810 offsetof(dbuf_dirty_record_t
, dr_dirty_node
));
811 odn
->dn_free_ranges
[i
] = NULL
;
812 odn
->dn_next_nlevels
[i
] = 0;
813 odn
->dn_next_indblkshift
[i
] = 0;
814 odn
->dn_next_bonustype
[i
] = 0;
815 odn
->dn_rm_spillblk
[i
] = 0;
816 odn
->dn_next_bonuslen
[i
] = 0;
817 odn
->dn_next_blksz
[i
] = 0;
819 odn
->dn_allocated_txg
= 0;
820 odn
->dn_free_txg
= 0;
821 odn
->dn_assigned_txg
= 0;
822 odn
->dn_dirtyctx
= 0;
823 odn
->dn_dirtyctx_firstset
= NULL
;
824 odn
->dn_have_spill
= B_FALSE
;
827 odn
->dn_oldflags
= 0;
832 odn
->dn_id_flags
= 0;
838 odn
->dn_moved
= (uint8_t)-1;
844 dnode_move(void *buf
, void *newbuf
, size_t size
, void *arg
)
846 dnode_t
*odn
= buf
, *ndn
= newbuf
;
852 * The dnode is on the objset's list of known dnodes if the objset
853 * pointer is valid. We set the low bit of the objset pointer when
854 * freeing the dnode to invalidate it, and the memory patterns written
855 * by kmem (baddcafe and deadbeef) set at least one of the two low bits.
856 * A newly created dnode sets the objset pointer last of all to indicate
857 * that the dnode is known and in a valid state to be moved by this
861 if (!POINTER_IS_VALID(os
)) {
862 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_invalid
);
863 return (KMEM_CBRC_DONT_KNOW
);
867 * Ensure that the objset does not go away during the move.
869 rw_enter(&os_lock
, RW_WRITER
);
870 if (os
!= odn
->dn_objset
) {
872 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_recheck1
);
873 return (KMEM_CBRC_DONT_KNOW
);
877 * If the dnode is still valid, then so is the objset. We know that no
878 * valid objset can be freed while we hold os_lock, so we can safely
879 * ensure that the objset remains in use.
881 mutex_enter(&os
->os_lock
);
884 * Recheck the objset pointer in case the dnode was removed just before
885 * acquiring the lock.
887 if (os
!= odn
->dn_objset
) {
888 mutex_exit(&os
->os_lock
);
890 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_recheck2
);
891 return (KMEM_CBRC_DONT_KNOW
);
895 * At this point we know that as long as we hold os->os_lock, the dnode
896 * cannot be freed and fields within the dnode can be safely accessed.
897 * The objset listing this dnode cannot go away as long as this dnode is
901 if (DMU_OBJECT_IS_SPECIAL(odn
->dn_object
)) {
902 mutex_exit(&os
->os_lock
);
903 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_special
);
904 return (KMEM_CBRC_NO
);
906 ASSERT(odn
->dn_dbuf
!= NULL
); /* only "special" dnodes have no parent */
909 * Lock the dnode handle to prevent the dnode from obtaining any new
910 * holds. This also prevents the descendant dbufs and the bonus dbuf
911 * from accessing the dnode, so that we can discount their holds. The
912 * handle is safe to access because we know that while the dnode cannot
913 * go away, neither can its handle. Once we hold dnh_zrlock, we can
914 * safely move any dnode referenced only by dbufs.
916 if (!zrl_tryenter(&odn
->dn_handle
->dnh_zrlock
)) {
917 mutex_exit(&os
->os_lock
);
918 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_handle
);
919 return (KMEM_CBRC_LATER
);
923 * Ensure a consistent view of the dnode's holds and the dnode's dbufs.
924 * We need to guarantee that there is a hold for every dbuf in order to
925 * determine whether the dnode is actively referenced. Falsely matching
926 * a dbuf to an active hold would lead to an unsafe move. It's possible
927 * that a thread already having an active dnode hold is about to add a
928 * dbuf, and we can't compare hold and dbuf counts while the add is in
931 if (!rw_tryenter(&odn
->dn_struct_rwlock
, RW_WRITER
)) {
932 zrl_exit(&odn
->dn_handle
->dnh_zrlock
);
933 mutex_exit(&os
->os_lock
);
934 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_rwlock
);
935 return (KMEM_CBRC_LATER
);
939 * A dbuf may be removed (evicted) without an active dnode hold. In that
940 * case, the dbuf count is decremented under the handle lock before the
941 * dbuf's hold is released. This order ensures that if we count the hold
942 * after the dbuf is removed but before its hold is released, we will
943 * treat the unmatched hold as active and exit safely. If we count the
944 * hold before the dbuf is removed, the hold is discounted, and the
945 * removal is blocked until the move completes.
947 refcount
= refcount_count(&odn
->dn_holds
);
948 ASSERT(refcount
>= 0);
949 dbufs
= odn
->dn_dbufs_count
;
951 /* We can't have more dbufs than dnode holds. */
952 ASSERT3U(dbufs
, <=, refcount
);
953 DTRACE_PROBE3(dnode__move
, dnode_t
*, odn
, int64_t, refcount
,
956 if (refcount
> dbufs
) {
957 rw_exit(&odn
->dn_struct_rwlock
);
958 zrl_exit(&odn
->dn_handle
->dnh_zrlock
);
959 mutex_exit(&os
->os_lock
);
960 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_active
);
961 return (KMEM_CBRC_LATER
);
964 rw_exit(&odn
->dn_struct_rwlock
);
967 * At this point we know that anyone with a hold on the dnode is not
968 * actively referencing it. The dnode is known and in a valid state to
969 * move. We're holding the locks needed to execute the critical section.
971 dnode_move_impl(odn
, ndn
);
973 list_link_replace(&odn
->dn_link
, &ndn
->dn_link
);
974 /* If the dnode was safe to move, the refcount cannot have changed. */
975 ASSERT(refcount
== refcount_count(&ndn
->dn_holds
));
976 ASSERT(dbufs
== ndn
->dn_dbufs_count
);
977 zrl_exit(&ndn
->dn_handle
->dnh_zrlock
); /* handle has moved */
978 mutex_exit(&os
->os_lock
);
980 return (KMEM_CBRC_YES
);
985 dnode_special_close(dnode_handle_t
*dnh
)
987 dnode_t
*dn
= dnh
->dnh_dnode
;
990 * Wait for final references to the dnode to clear. This can
991 * only happen if the arc is asyncronously evicting state that
992 * has a hold on this dnode while we are trying to evict this
995 while (refcount_count(&dn
->dn_holds
) > 0)
997 ASSERT(dn
->dn_dbuf
== NULL
||
998 dmu_buf_get_user(&dn
->dn_dbuf
->db
) == NULL
);
999 zrl_add(&dnh
->dnh_zrlock
);
1000 dnode_destroy(dn
); /* implicit zrl_remove() */
1001 zrl_destroy(&dnh
->dnh_zrlock
);
1002 dnh
->dnh_dnode
= NULL
;
1006 dnode_special_open(objset_t
*os
, dnode_phys_t
*dnp
, uint64_t object
,
1007 dnode_handle_t
*dnh
)
1011 dn
= dnode_create(os
, dnp
, NULL
, object
, dnh
);
1012 zrl_init(&dnh
->dnh_zrlock
);
1017 dnode_buf_pageout(void *dbu
)
1019 dnode_children_t
*children_dnodes
= dbu
;
1022 for (i
= 0; i
< children_dnodes
->dnc_count
; i
++) {
1023 dnode_handle_t
*dnh
= &children_dnodes
->dnc_children
[i
];
1027 * The dnode handle lock guards against the dnode moving to
1028 * another valid address, so there is no need here to guard
1029 * against changes to or from NULL.
1031 if (dnh
->dnh_dnode
== NULL
) {
1032 zrl_destroy(&dnh
->dnh_zrlock
);
1036 zrl_add(&dnh
->dnh_zrlock
);
1037 dn
= dnh
->dnh_dnode
;
1039 * If there are holds on this dnode, then there should
1040 * be holds on the dnode's containing dbuf as well; thus
1041 * it wouldn't be eligible for eviction and this function
1042 * would not have been called.
1044 ASSERT(refcount_is_zero(&dn
->dn_holds
));
1045 ASSERT(refcount_is_zero(&dn
->dn_tx_holds
));
1047 dnode_destroy(dn
); /* implicit zrl_remove() */
1048 zrl_destroy(&dnh
->dnh_zrlock
);
1049 dnh
->dnh_dnode
= NULL
;
1051 kmem_free(children_dnodes
, sizeof (dnode_children_t
) +
1052 children_dnodes
->dnc_count
* sizeof (dnode_handle_t
));
1057 * EINVAL - invalid object number.
1059 * succeeds even for free dnodes.
1062 dnode_hold_impl(objset_t
*os
, uint64_t object
, int flag
,
1063 void *tag
, dnode_t
**dnp
)
1066 int drop_struct_lock
= FALSE
;
1071 dnode_children_t
*children_dnodes
;
1072 dnode_handle_t
*dnh
;
1075 * If you are holding the spa config lock as writer, you shouldn't
1076 * be asking the DMU to do *anything* unless it's the root pool
1077 * which may require us to read from the root filesystem while
1078 * holding some (not all) of the locks as writer.
1080 ASSERT(spa_config_held(os
->os_spa
, SCL_ALL
, RW_WRITER
) == 0 ||
1081 (spa_is_root(os
->os_spa
) &&
1082 spa_config_held(os
->os_spa
, SCL_STATE
, RW_WRITER
)));
1084 if (object
== DMU_USERUSED_OBJECT
|| object
== DMU_GROUPUSED_OBJECT
) {
1085 dn
= (object
== DMU_USERUSED_OBJECT
) ?
1086 DMU_USERUSED_DNODE(os
) : DMU_GROUPUSED_DNODE(os
);
1088 return (SET_ERROR(ENOENT
));
1090 if ((flag
& DNODE_MUST_BE_ALLOCATED
) && type
== DMU_OT_NONE
)
1091 return (SET_ERROR(ENOENT
));
1092 if ((flag
& DNODE_MUST_BE_FREE
) && type
!= DMU_OT_NONE
)
1093 return (SET_ERROR(EEXIST
));
1095 (void) refcount_add(&dn
->dn_holds
, tag
);
1100 if (object
== 0 || object
>= DN_MAX_OBJECT
)
1101 return (SET_ERROR(EINVAL
));
1103 mdn
= DMU_META_DNODE(os
);
1104 ASSERT(mdn
->dn_object
== DMU_META_DNODE_OBJECT
);
1108 if (!RW_WRITE_HELD(&mdn
->dn_struct_rwlock
)) {
1109 rw_enter(&mdn
->dn_struct_rwlock
, RW_READER
);
1110 drop_struct_lock
= TRUE
;
1113 blk
= dbuf_whichblock(mdn
, 0, object
* sizeof (dnode_phys_t
));
1115 db
= dbuf_hold(mdn
, blk
, FTAG
);
1116 if (drop_struct_lock
)
1117 rw_exit(&mdn
->dn_struct_rwlock
);
1119 return (SET_ERROR(EIO
));
1120 err
= dbuf_read(db
, NULL
, DB_RF_CANFAIL
);
1122 dbuf_rele(db
, FTAG
);
1126 ASSERT3U(db
->db
.db_size
, >=, 1<<DNODE_SHIFT
);
1127 epb
= db
->db
.db_size
>> DNODE_SHIFT
;
1129 idx
= object
& (epb
-1);
1131 ASSERT(DB_DNODE(db
)->dn_type
== DMU_OT_DNODE
);
1132 children_dnodes
= dmu_buf_get_user(&db
->db
);
1133 if (children_dnodes
== NULL
) {
1135 dnode_children_t
*winner
;
1136 children_dnodes
= kmem_zalloc(sizeof (dnode_children_t
) +
1137 epb
* sizeof (dnode_handle_t
), KM_SLEEP
);
1138 children_dnodes
->dnc_count
= epb
;
1139 dnh
= &children_dnodes
->dnc_children
[0];
1140 for (i
= 0; i
< epb
; i
++) {
1141 zrl_init(&dnh
[i
].dnh_zrlock
);
1143 dmu_buf_init_user(&children_dnodes
->dnc_dbu
,
1144 dnode_buf_pageout
, NULL
);
1145 winner
= dmu_buf_set_user(&db
->db
, &children_dnodes
->dnc_dbu
);
1146 if (winner
!= NULL
) {
1148 for (i
= 0; i
< epb
; i
++) {
1149 zrl_destroy(&dnh
[i
].dnh_zrlock
);
1152 kmem_free(children_dnodes
, sizeof (dnode_children_t
) +
1153 epb
* sizeof (dnode_handle_t
));
1154 children_dnodes
= winner
;
1157 ASSERT(children_dnodes
->dnc_count
== epb
);
1159 dnh
= &children_dnodes
->dnc_children
[idx
];
1160 zrl_add(&dnh
->dnh_zrlock
);
1161 dn
= dnh
->dnh_dnode
;
1163 dnode_phys_t
*phys
= (dnode_phys_t
*)db
->db
.db_data
+idx
;
1165 dn
= dnode_create(os
, phys
, db
, object
, dnh
);
1168 mutex_enter(&dn
->dn_mtx
);
1170 if (dn
->dn_free_txg
||
1171 ((flag
& DNODE_MUST_BE_ALLOCATED
) && type
== DMU_OT_NONE
) ||
1172 ((flag
& DNODE_MUST_BE_FREE
) &&
1173 (type
!= DMU_OT_NONE
|| !refcount_is_zero(&dn
->dn_holds
)))) {
1174 mutex_exit(&dn
->dn_mtx
);
1175 zrl_remove(&dnh
->dnh_zrlock
);
1176 dbuf_rele(db
, FTAG
);
1177 return (type
== DMU_OT_NONE
? ENOENT
: EEXIST
);
1179 if (refcount_add(&dn
->dn_holds
, tag
) == 1)
1180 dbuf_add_ref(db
, dnh
);
1181 mutex_exit(&dn
->dn_mtx
);
1183 /* Now we can rely on the hold to prevent the dnode from moving. */
1184 zrl_remove(&dnh
->dnh_zrlock
);
1187 ASSERT3P(dn
->dn_dbuf
, ==, db
);
1188 ASSERT3U(dn
->dn_object
, ==, object
);
1189 dbuf_rele(db
, FTAG
);
1196 * Return held dnode if the object is allocated, NULL if not.
1199 dnode_hold(objset_t
*os
, uint64_t object
, void *tag
, dnode_t
**dnp
)
1201 return (dnode_hold_impl(os
, object
, DNODE_MUST_BE_ALLOCATED
, tag
, dnp
));
1205 * Can only add a reference if there is already at least one
1206 * reference on the dnode. Returns FALSE if unable to add a
1210 dnode_add_ref(dnode_t
*dn
, void *tag
)
1212 mutex_enter(&dn
->dn_mtx
);
1213 if (refcount_is_zero(&dn
->dn_holds
)) {
1214 mutex_exit(&dn
->dn_mtx
);
1217 VERIFY(1 < refcount_add(&dn
->dn_holds
, tag
));
1218 mutex_exit(&dn
->dn_mtx
);
1223 dnode_rele(dnode_t
*dn
, void *tag
)
1225 mutex_enter(&dn
->dn_mtx
);
1226 dnode_rele_and_unlock(dn
, tag
);
1230 dnode_rele_and_unlock(dnode_t
*dn
, void *tag
)
1233 /* Get while the hold prevents the dnode from moving. */
1234 dmu_buf_impl_t
*db
= dn
->dn_dbuf
;
1235 dnode_handle_t
*dnh
= dn
->dn_handle
;
1237 refs
= refcount_remove(&dn
->dn_holds
, tag
);
1238 mutex_exit(&dn
->dn_mtx
);
1241 * It's unsafe to release the last hold on a dnode by dnode_rele() or
1242 * indirectly by dbuf_rele() while relying on the dnode handle to
1243 * prevent the dnode from moving, since releasing the last hold could
1244 * result in the dnode's parent dbuf evicting its dnode handles. For
1245 * that reason anyone calling dnode_rele() or dbuf_rele() without some
1246 * other direct or indirect hold on the dnode must first drop the dnode
1249 ASSERT(refs
> 0 || dnh
->dnh_zrlock
.zr_owner
!= curthread
);
1251 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */
1252 if (refs
== 0 && db
!= NULL
) {
1254 * Another thread could add a hold to the dnode handle in
1255 * dnode_hold_impl() while holding the parent dbuf. Since the
1256 * hold on the parent dbuf prevents the handle from being
1257 * destroyed, the hold on the handle is OK. We can't yet assert
1258 * that the handle has zero references, but that will be
1259 * asserted anyway when the handle gets destroyed.
1266 dnode_setdirty(dnode_t
*dn
, dmu_tx_t
*tx
)
1268 objset_t
*os
= dn
->dn_objset
;
1269 uint64_t txg
= tx
->tx_txg
;
1271 if (DMU_OBJECT_IS_SPECIAL(dn
->dn_object
)) {
1272 dsl_dataset_dirty(os
->os_dsl_dataset
, tx
);
1279 mutex_enter(&dn
->dn_mtx
);
1280 ASSERT(dn
->dn_phys
->dn_type
|| dn
->dn_allocated_txg
);
1281 ASSERT(dn
->dn_free_txg
== 0 || dn
->dn_free_txg
>= txg
);
1282 mutex_exit(&dn
->dn_mtx
);
1286 * Determine old uid/gid when necessary
1288 dmu_objset_userquota_get_ids(dn
, B_TRUE
, tx
);
1290 mutex_enter(&os
->os_lock
);
1293 * If we are already marked dirty, we're done.
1295 if (list_link_active(&dn
->dn_dirty_link
[txg
& TXG_MASK
])) {
1296 mutex_exit(&os
->os_lock
);
1300 ASSERT(!refcount_is_zero(&dn
->dn_holds
) ||
1301 !avl_is_empty(&dn
->dn_dbufs
));
1302 ASSERT(dn
->dn_datablksz
!= 0);
1303 ASSERT0(dn
->dn_next_bonuslen
[txg
&TXG_MASK
]);
1304 ASSERT0(dn
->dn_next_blksz
[txg
&TXG_MASK
]);
1305 ASSERT0(dn
->dn_next_bonustype
[txg
&TXG_MASK
]);
1307 dprintf_ds(os
->os_dsl_dataset
, "obj=%llu txg=%llu\n",
1308 dn
->dn_object
, txg
);
1310 if (dn
->dn_free_txg
> 0 && dn
->dn_free_txg
<= txg
) {
1311 list_insert_tail(&os
->os_free_dnodes
[txg
&TXG_MASK
], dn
);
1313 list_insert_tail(&os
->os_dirty_dnodes
[txg
&TXG_MASK
], dn
);
1316 mutex_exit(&os
->os_lock
);
1319 * The dnode maintains a hold on its containing dbuf as
1320 * long as there are holds on it. Each instantiated child
1321 * dbuf maintains a hold on the dnode. When the last child
1322 * drops its hold, the dnode will drop its hold on the
1323 * containing dbuf. We add a "dirty hold" here so that the
1324 * dnode will hang around after we finish processing its
1327 VERIFY(dnode_add_ref(dn
, (void *)(uintptr_t)tx
->tx_txg
));
1329 (void) dbuf_dirty(dn
->dn_dbuf
, tx
);
1331 dsl_dataset_dirty(os
->os_dsl_dataset
, tx
);
1335 dnode_free(dnode_t
*dn
, dmu_tx_t
*tx
)
1337 int txgoff
= tx
->tx_txg
& TXG_MASK
;
1339 dprintf("dn=%p txg=%llu\n", dn
, tx
->tx_txg
);
1341 /* we should be the only holder... hopefully */
1342 /* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */
1344 mutex_enter(&dn
->dn_mtx
);
1345 if (dn
->dn_type
== DMU_OT_NONE
|| dn
->dn_free_txg
) {
1346 mutex_exit(&dn
->dn_mtx
);
1349 dn
->dn_free_txg
= tx
->tx_txg
;
1350 mutex_exit(&dn
->dn_mtx
);
1353 * If the dnode is already dirty, it needs to be moved from
1354 * the dirty list to the free list.
1356 mutex_enter(&dn
->dn_objset
->os_lock
);
1357 if (list_link_active(&dn
->dn_dirty_link
[txgoff
])) {
1358 list_remove(&dn
->dn_objset
->os_dirty_dnodes
[txgoff
], dn
);
1359 list_insert_tail(&dn
->dn_objset
->os_free_dnodes
[txgoff
], dn
);
1360 mutex_exit(&dn
->dn_objset
->os_lock
);
1362 mutex_exit(&dn
->dn_objset
->os_lock
);
1363 dnode_setdirty(dn
, tx
);
1368 * Try to change the block size for the indicated dnode. This can only
1369 * succeed if there are no blocks allocated or dirty beyond first block
1372 dnode_set_blksz(dnode_t
*dn
, uint64_t size
, int ibs
, dmu_tx_t
*tx
)
1377 ASSERT3U(size
, <=, spa_maxblocksize(dmu_objset_spa(dn
->dn_objset
)));
1379 size
= SPA_MINBLOCKSIZE
;
1381 size
= P2ROUNDUP(size
, SPA_MINBLOCKSIZE
);
1383 if (ibs
== dn
->dn_indblkshift
)
1386 if (size
>> SPA_MINBLOCKSHIFT
== dn
->dn_datablkszsec
&& ibs
== 0)
1389 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
1391 /* Check for any allocated blocks beyond the first */
1392 if (dn
->dn_maxblkid
!= 0)
1395 mutex_enter(&dn
->dn_dbufs_mtx
);
1396 for (db
= avl_first(&dn
->dn_dbufs
); db
!= NULL
;
1397 db
= AVL_NEXT(&dn
->dn_dbufs
, db
)) {
1398 if (db
->db_blkid
!= 0 && db
->db_blkid
!= DMU_BONUS_BLKID
&&
1399 db
->db_blkid
!= DMU_SPILL_BLKID
) {
1400 mutex_exit(&dn
->dn_dbufs_mtx
);
1404 mutex_exit(&dn
->dn_dbufs_mtx
);
1406 if (ibs
&& dn
->dn_nlevels
!= 1)
1409 /* resize the old block */
1410 err
= dbuf_hold_impl(dn
, 0, 0, TRUE
, FALSE
, FTAG
, &db
);
1412 dbuf_new_size(db
, size
, tx
);
1413 else if (err
!= ENOENT
)
1416 dnode_setdblksz(dn
, size
);
1417 dnode_setdirty(dn
, tx
);
1418 dn
->dn_next_blksz
[tx
->tx_txg
&TXG_MASK
] = size
;
1420 dn
->dn_indblkshift
= ibs
;
1421 dn
->dn_next_indblkshift
[tx
->tx_txg
&TXG_MASK
] = ibs
;
1423 /* rele after we have fixed the blocksize in the dnode */
1425 dbuf_rele(db
, FTAG
);
1427 rw_exit(&dn
->dn_struct_rwlock
);
1431 rw_exit(&dn
->dn_struct_rwlock
);
1432 return (SET_ERROR(ENOTSUP
));
1435 /* read-holding callers must not rely on the lock being continuously held */
1437 dnode_new_blkid(dnode_t
*dn
, uint64_t blkid
, dmu_tx_t
*tx
, boolean_t have_read
)
1439 uint64_t txgoff
= tx
->tx_txg
& TXG_MASK
;
1440 int epbs
, new_nlevels
;
1443 ASSERT(blkid
!= DMU_BONUS_BLKID
);
1446 RW_READ_HELD(&dn
->dn_struct_rwlock
) :
1447 RW_WRITE_HELD(&dn
->dn_struct_rwlock
));
1450 * if we have a read-lock, check to see if we need to do any work
1451 * before upgrading to a write-lock.
1454 if (blkid
<= dn
->dn_maxblkid
)
1457 if (!rw_tryupgrade(&dn
->dn_struct_rwlock
)) {
1458 rw_exit(&dn
->dn_struct_rwlock
);
1459 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
1463 if (blkid
<= dn
->dn_maxblkid
)
1466 dn
->dn_maxblkid
= blkid
;
1469 * Compute the number of levels necessary to support the new maxblkid.
1472 epbs
= dn
->dn_indblkshift
- SPA_BLKPTRSHIFT
;
1473 for (sz
= dn
->dn_nblkptr
;
1474 sz
<= blkid
&& sz
>= dn
->dn_nblkptr
; sz
<<= epbs
)
1477 if (new_nlevels
> dn
->dn_nlevels
) {
1478 int old_nlevels
= dn
->dn_nlevels
;
1481 dbuf_dirty_record_t
*new, *dr
, *dr_next
;
1483 dn
->dn_nlevels
= new_nlevels
;
1485 ASSERT3U(new_nlevels
, >, dn
->dn_next_nlevels
[txgoff
]);
1486 dn
->dn_next_nlevels
[txgoff
] = new_nlevels
;
1488 /* dirty the left indirects */
1489 db
= dbuf_hold_level(dn
, old_nlevels
, 0, FTAG
);
1491 new = dbuf_dirty(db
, tx
);
1492 dbuf_rele(db
, FTAG
);
1494 /* transfer the dirty records to the new indirect */
1495 mutex_enter(&dn
->dn_mtx
);
1496 mutex_enter(&new->dt
.di
.dr_mtx
);
1497 list
= &dn
->dn_dirty_records
[txgoff
];
1498 for (dr
= list_head(list
); dr
; dr
= dr_next
) {
1499 dr_next
= list_next(&dn
->dn_dirty_records
[txgoff
], dr
);
1500 if (dr
->dr_dbuf
->db_level
!= new_nlevels
-1 &&
1501 dr
->dr_dbuf
->db_blkid
!= DMU_BONUS_BLKID
&&
1502 dr
->dr_dbuf
->db_blkid
!= DMU_SPILL_BLKID
) {
1503 ASSERT(dr
->dr_dbuf
->db_level
== old_nlevels
-1);
1504 list_remove(&dn
->dn_dirty_records
[txgoff
], dr
);
1505 list_insert_tail(&new->dt
.di
.dr_children
, dr
);
1506 dr
->dr_parent
= new;
1509 mutex_exit(&new->dt
.di
.dr_mtx
);
1510 mutex_exit(&dn
->dn_mtx
);
1515 rw_downgrade(&dn
->dn_struct_rwlock
);
1519 dnode_dirty_l1(dnode_t
*dn
, uint64_t l1blkid
, dmu_tx_t
*tx
)
1521 dmu_buf_impl_t
*db
= dbuf_hold_level(dn
, 1, l1blkid
, FTAG
);
1523 dmu_buf_will_dirty(&db
->db
, tx
);
1524 dbuf_rele(db
, FTAG
);
1529 dnode_free_range(dnode_t
*dn
, uint64_t off
, uint64_t len
, dmu_tx_t
*tx
)
1532 uint64_t blkoff
, blkid
, nblks
;
1533 int blksz
, blkshift
, head
, tail
;
1537 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
1538 blksz
= dn
->dn_datablksz
;
1539 blkshift
= dn
->dn_datablkshift
;
1540 epbs
= dn
->dn_indblkshift
- SPA_BLKPTRSHIFT
;
1542 if (len
== DMU_OBJECT_END
) {
1543 len
= UINT64_MAX
- off
;
1548 * First, block align the region to free:
1551 head
= P2NPHASE(off
, blksz
);
1552 blkoff
= P2PHASE(off
, blksz
);
1553 if ((off
>> blkshift
) > dn
->dn_maxblkid
)
1556 ASSERT(dn
->dn_maxblkid
== 0);
1557 if (off
== 0 && len
>= blksz
) {
1559 * Freeing the whole block; fast-track this request.
1560 * Note that we won't dirty any indirect blocks,
1561 * which is fine because we will be freeing the entire
1562 * file and thus all indirect blocks will be freed
1563 * by free_children().
1568 } else if (off
>= blksz
) {
1569 /* Freeing past end-of-data */
1572 /* Freeing part of the block. */
1574 ASSERT3U(head
, >, 0);
1578 /* zero out any partial block data at the start of the range */
1580 ASSERT3U(blkoff
+ head
, ==, blksz
);
1583 if (dbuf_hold_impl(dn
, 0, dbuf_whichblock(dn
, 0, off
),
1584 TRUE
, FALSE
, FTAG
, &db
) == 0) {
1587 /* don't dirty if it isn't on disk and isn't dirty */
1588 if (db
->db_last_dirty
||
1589 (db
->db_blkptr
&& !BP_IS_HOLE(db
->db_blkptr
))) {
1590 rw_exit(&dn
->dn_struct_rwlock
);
1591 dmu_buf_will_dirty(&db
->db
, tx
);
1592 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
1593 data
= db
->db
.db_data
;
1594 bzero(data
+ blkoff
, head
);
1596 dbuf_rele(db
, FTAG
);
1602 /* If the range was less than one block, we're done */
1606 /* If the remaining range is past end of file, we're done */
1607 if ((off
>> blkshift
) > dn
->dn_maxblkid
)
1610 ASSERT(ISP2(blksz
));
1614 tail
= P2PHASE(len
, blksz
);
1616 ASSERT0(P2PHASE(off
, blksz
));
1617 /* zero out any partial block data at the end of the range */
1621 if (dbuf_hold_impl(dn
, 0, dbuf_whichblock(dn
, 0, off
+len
),
1622 TRUE
, FALSE
, FTAG
, &db
) == 0) {
1623 /* don't dirty if not on disk and not dirty */
1624 if (db
->db_last_dirty
||
1625 (db
->db_blkptr
&& !BP_IS_HOLE(db
->db_blkptr
))) {
1626 rw_exit(&dn
->dn_struct_rwlock
);
1627 dmu_buf_will_dirty(&db
->db
, tx
);
1628 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
1629 bzero(db
->db
.db_data
, tail
);
1631 dbuf_rele(db
, FTAG
);
1636 /* If the range did not include a full block, we are done */
1640 ASSERT(IS_P2ALIGNED(off
, blksz
));
1641 ASSERT(trunc
|| IS_P2ALIGNED(len
, blksz
));
1642 blkid
= off
>> blkshift
;
1643 nblks
= len
>> blkshift
;
1648 * Dirty all the indirect blocks in this range. Note that only
1649 * the first and last indirect blocks can actually be written
1650 * (if they were partially freed) -- they must be dirtied, even if
1651 * they do not exist on disk yet. The interior blocks will
1652 * be freed by free_children(), so they will not actually be written.
1653 * Even though these interior blocks will not be written, we
1654 * dirty them for two reasons:
1656 * - It ensures that the indirect blocks remain in memory until
1657 * syncing context. (They have already been prefetched by
1658 * dmu_tx_hold_free(), so we don't have to worry about reading
1659 * them serially here.)
1661 * - The dirty space accounting will put pressure on the txg sync
1662 * mechanism to begin syncing, and to delay transactions if there
1663 * is a large amount of freeing. Even though these indirect
1664 * blocks will not be written, we could need to write the same
1665 * amount of space if we copy the freed BPs into deadlists.
1667 if (dn
->dn_nlevels
> 1) {
1668 uint64_t first
, last
;
1670 first
= blkid
>> epbs
;
1671 dnode_dirty_l1(dn
, first
, tx
);
1673 last
= dn
->dn_maxblkid
>> epbs
;
1675 last
= (blkid
+ nblks
- 1) >> epbs
;
1677 dnode_dirty_l1(dn
, last
, tx
);
1679 int shift
= dn
->dn_datablkshift
+ dn
->dn_indblkshift
-
1681 for (uint64_t i
= first
+ 1; i
< last
; i
++) {
1683 * Set i to the blockid of the next non-hole
1684 * level-1 indirect block at or after i. Note
1685 * that dnode_next_offset() operates in terms of
1686 * level-0-equivalent bytes.
1688 uint64_t ibyte
= i
<< shift
;
1689 int err
= dnode_next_offset(dn
, DNODE_FIND_HAVELOCK
,
1696 * Normally we should not see an error, either
1697 * from dnode_next_offset() or dbuf_hold_level()
1698 * (except for ESRCH from dnode_next_offset).
1699 * If there is an i/o error, then when we read
1700 * this block in syncing context, it will use
1701 * ZIO_FLAG_MUSTSUCCEED, and thus hang/panic according
1702 * to the "failmode" property. dnode_next_offset()
1703 * doesn't have a flag to indicate MUSTSUCCEED.
1708 dnode_dirty_l1(dn
, i
, tx
);
1714 * Add this range to the dnode range list.
1715 * We will finish up this free operation in the syncing phase.
1717 mutex_enter(&dn
->dn_mtx
);
1718 int txgoff
= tx
->tx_txg
& TXG_MASK
;
1719 if (dn
->dn_free_ranges
[txgoff
] == NULL
) {
1720 dn
->dn_free_ranges
[txgoff
] =
1721 range_tree_create(NULL
, NULL
, &dn
->dn_mtx
);
1723 range_tree_clear(dn
->dn_free_ranges
[txgoff
], blkid
, nblks
);
1724 range_tree_add(dn
->dn_free_ranges
[txgoff
], blkid
, nblks
);
1725 dprintf_dnode(dn
, "blkid=%llu nblks=%llu txg=%llu\n",
1726 blkid
, nblks
, tx
->tx_txg
);
1727 mutex_exit(&dn
->dn_mtx
);
1729 dbuf_free_range(dn
, blkid
, blkid
+ nblks
- 1, tx
);
1730 dnode_setdirty(dn
, tx
);
1733 rw_exit(&dn
->dn_struct_rwlock
);
1737 dnode_spill_freed(dnode_t
*dn
)
1741 mutex_enter(&dn
->dn_mtx
);
1742 for (i
= 0; i
< TXG_SIZE
; i
++) {
1743 if (dn
->dn_rm_spillblk
[i
] == DN_KILL_SPILLBLK
)
1746 mutex_exit(&dn
->dn_mtx
);
1747 return (i
< TXG_SIZE
);
1750 /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */
1752 dnode_block_freed(dnode_t
*dn
, uint64_t blkid
)
1754 void *dp
= spa_get_dsl(dn
->dn_objset
->os_spa
);
1757 if (blkid
== DMU_BONUS_BLKID
)
1761 * If we're in the process of opening the pool, dp will not be
1762 * set yet, but there shouldn't be anything dirty.
1767 if (dn
->dn_free_txg
)
1770 if (blkid
== DMU_SPILL_BLKID
)
1771 return (dnode_spill_freed(dn
));
1773 mutex_enter(&dn
->dn_mtx
);
1774 for (i
= 0; i
< TXG_SIZE
; i
++) {
1775 if (dn
->dn_free_ranges
[i
] != NULL
&&
1776 range_tree_contains(dn
->dn_free_ranges
[i
], blkid
, 1))
1779 mutex_exit(&dn
->dn_mtx
);
1780 return (i
< TXG_SIZE
);
1783 /* call from syncing context when we actually write/free space for this dnode */
1785 dnode_diduse_space(dnode_t
*dn
, int64_t delta
)
1788 dprintf_dnode(dn
, "dn=%p dnp=%p used=%llu delta=%lld\n",
1790 (u_longlong_t
)dn
->dn_phys
->dn_used
,
1793 mutex_enter(&dn
->dn_mtx
);
1794 space
= DN_USED_BYTES(dn
->dn_phys
);
1796 ASSERT3U(space
+ delta
, >=, space
); /* no overflow */
1798 ASSERT3U(space
, >=, -delta
); /* no underflow */
1801 if (spa_version(dn
->dn_objset
->os_spa
) < SPA_VERSION_DNODE_BYTES
) {
1802 ASSERT((dn
->dn_phys
->dn_flags
& DNODE_FLAG_USED_BYTES
) == 0);
1803 ASSERT0(P2PHASE(space
, 1<<DEV_BSHIFT
));
1804 dn
->dn_phys
->dn_used
= space
>> DEV_BSHIFT
;
1806 dn
->dn_phys
->dn_used
= space
;
1807 dn
->dn_phys
->dn_flags
|= DNODE_FLAG_USED_BYTES
;
1809 mutex_exit(&dn
->dn_mtx
);
1813 * Call when we think we're going to write/free space in open context to track
1814 * the amount of memory in use by the currently open txg.
1817 dnode_willuse_space(dnode_t
*dn
, int64_t space
, dmu_tx_t
*tx
)
1819 objset_t
*os
= dn
->dn_objset
;
1820 dsl_dataset_t
*ds
= os
->os_dsl_dataset
;
1821 int64_t aspace
= spa_get_asize(os
->os_spa
, space
);
1824 dsl_dir_willuse_space(ds
->ds_dir
, aspace
, tx
);
1825 dsl_pool_dirty_space(dmu_tx_pool(tx
), space
, tx
);
1828 dmu_tx_willuse_space(tx
, aspace
);
1832 * Scans a block at the indicated "level" looking for a hole or data,
1833 * depending on 'flags'.
1835 * If level > 0, then we are scanning an indirect block looking at its
1836 * pointers. If level == 0, then we are looking at a block of dnodes.
1838 * If we don't find what we are looking for in the block, we return ESRCH.
1839 * Otherwise, return with *offset pointing to the beginning (if searching
1840 * forwards) or end (if searching backwards) of the range covered by the
1841 * block pointer we matched on (or dnode).
1843 * The basic search algorithm used below by dnode_next_offset() is to
1844 * use this function to search up the block tree (widen the search) until
1845 * we find something (i.e., we don't return ESRCH) and then search back
1846 * down the tree (narrow the search) until we reach our original search
1850 dnode_next_offset_level(dnode_t
*dn
, int flags
, uint64_t *offset
,
1851 int lvl
, uint64_t blkfill
, uint64_t txg
)
1853 dmu_buf_impl_t
*db
= NULL
;
1855 uint64_t epbs
= dn
->dn_phys
->dn_indblkshift
- SPA_BLKPTRSHIFT
;
1856 uint64_t epb
= 1ULL << epbs
;
1857 uint64_t minfill
, maxfill
;
1859 int i
, inc
, error
, span
;
1861 dprintf("probing object %llu offset %llx level %d of %u\n",
1862 dn
->dn_object
, *offset
, lvl
, dn
->dn_phys
->dn_nlevels
);
1864 hole
= ((flags
& DNODE_FIND_HOLE
) != 0);
1865 inc
= (flags
& DNODE_FIND_BACKWARDS
) ? -1 : 1;
1866 ASSERT(txg
== 0 || !hole
);
1868 if (lvl
== dn
->dn_phys
->dn_nlevels
) {
1870 epb
= dn
->dn_phys
->dn_nblkptr
;
1871 data
= dn
->dn_phys
->dn_blkptr
;
1873 uint64_t blkid
= dbuf_whichblock(dn
, lvl
, *offset
);
1874 error
= dbuf_hold_impl(dn
, lvl
, blkid
, TRUE
, FALSE
, FTAG
, &db
);
1876 if (error
!= ENOENT
)
1881 * This can only happen when we are searching up
1882 * the block tree for data. We don't really need to
1883 * adjust the offset, as we will just end up looking
1884 * at the pointer to this block in its parent, and its
1885 * going to be unallocated, so we will skip over it.
1887 return (SET_ERROR(ESRCH
));
1889 error
= dbuf_read(db
, NULL
, DB_RF_CANFAIL
| DB_RF_HAVESTRUCT
);
1891 dbuf_rele(db
, FTAG
);
1894 data
= db
->db
.db_data
;
1898 if (db
!= NULL
&& txg
!= 0 && (db
->db_blkptr
== NULL
||
1899 db
->db_blkptr
->blk_birth
<= txg
||
1900 BP_IS_HOLE(db
->db_blkptr
))) {
1902 * This can only happen when we are searching up the tree
1903 * and these conditions mean that we need to keep climbing.
1905 error
= SET_ERROR(ESRCH
);
1906 } else if (lvl
== 0) {
1907 dnode_phys_t
*dnp
= data
;
1909 ASSERT(dn
->dn_type
== DMU_OT_DNODE
);
1911 for (i
= (*offset
>> span
) & (blkfill
- 1);
1912 i
>= 0 && i
< blkfill
; i
+= inc
) {
1913 if ((dnp
[i
].dn_type
== DMU_OT_NONE
) == hole
)
1915 *offset
+= (1ULL << span
) * inc
;
1917 if (i
< 0 || i
== blkfill
)
1918 error
= SET_ERROR(ESRCH
);
1920 blkptr_t
*bp
= data
;
1921 uint64_t start
= *offset
;
1922 span
= (lvl
- 1) * epbs
+ dn
->dn_datablkshift
;
1924 maxfill
= blkfill
<< ((lvl
- 1) * epbs
);
1931 *offset
= *offset
>> span
;
1932 for (i
= BF64_GET(*offset
, 0, epbs
);
1933 i
>= 0 && i
< epb
; i
+= inc
) {
1934 if (BP_GET_FILL(&bp
[i
]) >= minfill
&&
1935 BP_GET_FILL(&bp
[i
]) <= maxfill
&&
1936 (hole
|| bp
[i
].blk_birth
> txg
))
1938 if (inc
> 0 || *offset
> 0)
1941 *offset
= *offset
<< span
;
1943 /* traversing backwards; position offset at the end */
1944 ASSERT3U(*offset
, <=, start
);
1945 *offset
= MIN(*offset
+ (1ULL << span
) - 1, start
);
1946 } else if (*offset
< start
) {
1949 if (i
< 0 || i
>= epb
)
1950 error
= SET_ERROR(ESRCH
);
1954 dbuf_rele(db
, FTAG
);
1960 * Find the next hole, data, or sparse region at or after *offset.
1961 * The value 'blkfill' tells us how many items we expect to find
1962 * in an L0 data block; this value is 1 for normal objects,
1963 * DNODES_PER_BLOCK for the meta dnode, and some fraction of
1964 * DNODES_PER_BLOCK when searching for sparse regions thereof.
1968 * dnode_next_offset(dn, flags, offset, 1, 1, 0);
1969 * Finds the next/previous hole/data in a file.
1970 * Used in dmu_offset_next().
1972 * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg);
1973 * Finds the next free/allocated dnode an objset's meta-dnode.
1974 * Only finds objects that have new contents since txg (ie.
1975 * bonus buffer changes and content removal are ignored).
1976 * Used in dmu_object_next().
1978 * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0);
1979 * Finds the next L2 meta-dnode bp that's at most 1/4 full.
1980 * Used in dmu_object_alloc().
1983 dnode_next_offset(dnode_t
*dn
, int flags
, uint64_t *offset
,
1984 int minlvl
, uint64_t blkfill
, uint64_t txg
)
1986 uint64_t initial_offset
= *offset
;
1990 if (!(flags
& DNODE_FIND_HAVELOCK
))
1991 rw_enter(&dn
->dn_struct_rwlock
, RW_READER
);
1993 if (dn
->dn_phys
->dn_nlevels
== 0) {
1994 error
= SET_ERROR(ESRCH
);
1998 if (dn
->dn_datablkshift
== 0) {
1999 if (*offset
< dn
->dn_datablksz
) {
2000 if (flags
& DNODE_FIND_HOLE
)
2001 *offset
= dn
->dn_datablksz
;
2003 error
= SET_ERROR(ESRCH
);
2008 maxlvl
= dn
->dn_phys
->dn_nlevels
;
2010 for (lvl
= minlvl
; lvl
<= maxlvl
; lvl
++) {
2011 error
= dnode_next_offset_level(dn
,
2012 flags
, offset
, lvl
, blkfill
, txg
);
2017 while (error
== 0 && --lvl
>= minlvl
) {
2018 error
= dnode_next_offset_level(dn
,
2019 flags
, offset
, lvl
, blkfill
, txg
);
2023 * There's always a "virtual hole" at the end of the object, even
2024 * if all BP's which physically exist are non-holes.
2026 if ((flags
& DNODE_FIND_HOLE
) && error
== ESRCH
&& txg
== 0 &&
2027 minlvl
== 1 && blkfill
== 1 && !(flags
& DNODE_FIND_BACKWARDS
)) {
2031 if (error
== 0 && (flags
& DNODE_FIND_BACKWARDS
?
2032 initial_offset
< *offset
: initial_offset
> *offset
))
2033 error
= SET_ERROR(ESRCH
);
2035 if (!(flags
& DNODE_FIND_HAVELOCK
))
2036 rw_exit(&dn
->dn_struct_rwlock
);