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.
27 #include <sys/zfs_context.h>
29 #include <sys/dnode.h>
31 #include <sys/dmu_impl.h>
32 #include <sys/dmu_tx.h>
33 #include <sys/dmu_objset.h>
34 #include <sys/dsl_dir.h>
35 #include <sys/dsl_dataset.h>
38 #include <sys/dmu_zfetch.h>
39 #include <sys/range_tree.h>
41 static kmem_cache_t
*dnode_cache
;
43 * Define DNODE_STATS to turn on statistic gathering. By default, it is only
44 * turned on when DEBUG is also defined.
51 #define DNODE_STAT_ADD(stat) ((stat)++)
53 #define DNODE_STAT_ADD(stat) /* nothing */
54 #endif /* DNODE_STATS */
56 static dnode_phys_t dnode_phys_zero
;
58 int zfs_default_bs
= SPA_MINBLOCKSHIFT
;
59 int zfs_default_ibs
= DN_MAX_INDBLKSHIFT
;
61 static kmem_cbrc_t
dnode_move(void *, void *, size_t, void *);
64 dbuf_compare(const void *x1
, const void *x2
)
66 const dmu_buf_impl_t
*d1
= x1
;
67 const dmu_buf_impl_t
*d2
= x2
;
69 if (d1
->db_level
< d2
->db_level
) {
72 if (d1
->db_level
> d2
->db_level
) {
76 if (d1
->db_blkid
< d2
->db_blkid
) {
79 if (d1
->db_blkid
> d2
->db_blkid
) {
83 if (d1
->db_state
== DB_SEARCH
) {
84 ASSERT3S(d2
->db_state
, !=, DB_SEARCH
);
86 } else if (d2
->db_state
== DB_SEARCH
) {
87 ASSERT3S(d1
->db_state
, !=, DB_SEARCH
);
91 if ((uintptr_t)d1
< (uintptr_t)d2
) {
94 if ((uintptr_t)d1
> (uintptr_t)d2
) {
102 dnode_cons(void *arg
, void *unused
, int kmflag
)
107 rw_init(&dn
->dn_struct_rwlock
, NULL
, RW_DEFAULT
, NULL
);
108 mutex_init(&dn
->dn_mtx
, NULL
, MUTEX_DEFAULT
, NULL
);
109 mutex_init(&dn
->dn_dbufs_mtx
, NULL
, MUTEX_DEFAULT
, NULL
);
110 cv_init(&dn
->dn_notxholds
, NULL
, CV_DEFAULT
, NULL
);
113 * Every dbuf has a reference, and dropping a tracked reference is
114 * O(number of references), so don't track dn_holds.
116 refcount_create_untracked(&dn
->dn_holds
);
117 refcount_create(&dn
->dn_tx_holds
);
118 list_link_init(&dn
->dn_link
);
120 bzero(&dn
->dn_next_nblkptr
[0], sizeof (dn
->dn_next_nblkptr
));
121 bzero(&dn
->dn_next_nlevels
[0], sizeof (dn
->dn_next_nlevels
));
122 bzero(&dn
->dn_next_indblkshift
[0], sizeof (dn
->dn_next_indblkshift
));
123 bzero(&dn
->dn_next_bonustype
[0], sizeof (dn
->dn_next_bonustype
));
124 bzero(&dn
->dn_rm_spillblk
[0], sizeof (dn
->dn_rm_spillblk
));
125 bzero(&dn
->dn_next_bonuslen
[0], sizeof (dn
->dn_next_bonuslen
));
126 bzero(&dn
->dn_next_blksz
[0], sizeof (dn
->dn_next_blksz
));
128 for (i
= 0; i
< TXG_SIZE
; i
++) {
129 list_link_init(&dn
->dn_dirty_link
[i
]);
130 dn
->dn_free_ranges
[i
] = NULL
;
131 list_create(&dn
->dn_dirty_records
[i
],
132 sizeof (dbuf_dirty_record_t
),
133 offsetof(dbuf_dirty_record_t
, dr_dirty_node
));
136 dn
->dn_allocated_txg
= 0;
138 dn
->dn_assigned_txg
= 0;
140 dn
->dn_dirtyctx_firstset
= NULL
;
142 dn
->dn_have_spill
= B_FALSE
;
152 dn
->dn_dbufs_count
= 0;
153 dn
->dn_unlisted_l0_blkid
= 0;
154 avl_create(&dn
->dn_dbufs
, dbuf_compare
, sizeof (dmu_buf_impl_t
),
155 offsetof(dmu_buf_impl_t
, db_link
));
163 dnode_dest(void *arg
, void *unused
)
168 rw_destroy(&dn
->dn_struct_rwlock
);
169 mutex_destroy(&dn
->dn_mtx
);
170 mutex_destroy(&dn
->dn_dbufs_mtx
);
171 cv_destroy(&dn
->dn_notxholds
);
172 refcount_destroy(&dn
->dn_holds
);
173 refcount_destroy(&dn
->dn_tx_holds
);
174 ASSERT(!list_link_active(&dn
->dn_link
));
176 for (i
= 0; i
< TXG_SIZE
; i
++) {
177 ASSERT(!list_link_active(&dn
->dn_dirty_link
[i
]));
178 ASSERT3P(dn
->dn_free_ranges
[i
], ==, NULL
);
179 list_destroy(&dn
->dn_dirty_records
[i
]);
180 ASSERT0(dn
->dn_next_nblkptr
[i
]);
181 ASSERT0(dn
->dn_next_nlevels
[i
]);
182 ASSERT0(dn
->dn_next_indblkshift
[i
]);
183 ASSERT0(dn
->dn_next_bonustype
[i
]);
184 ASSERT0(dn
->dn_rm_spillblk
[i
]);
185 ASSERT0(dn
->dn_next_bonuslen
[i
]);
186 ASSERT0(dn
->dn_next_blksz
[i
]);
189 ASSERT0(dn
->dn_allocated_txg
);
190 ASSERT0(dn
->dn_free_txg
);
191 ASSERT0(dn
->dn_assigned_txg
);
192 ASSERT0(dn
->dn_dirtyctx
);
193 ASSERT3P(dn
->dn_dirtyctx_firstset
, ==, NULL
);
194 ASSERT3P(dn
->dn_bonus
, ==, NULL
);
195 ASSERT(!dn
->dn_have_spill
);
196 ASSERT3P(dn
->dn_zio
, ==, NULL
);
197 ASSERT0(dn
->dn_oldused
);
198 ASSERT0(dn
->dn_oldflags
);
199 ASSERT0(dn
->dn_olduid
);
200 ASSERT0(dn
->dn_oldgid
);
201 ASSERT0(dn
->dn_newuid
);
202 ASSERT0(dn
->dn_newgid
);
203 ASSERT0(dn
->dn_id_flags
);
205 ASSERT0(dn
->dn_dbufs_count
);
206 ASSERT0(dn
->dn_unlisted_l0_blkid
);
207 avl_destroy(&dn
->dn_dbufs
);
213 ASSERT(dnode_cache
== NULL
);
214 dnode_cache
= kmem_cache_create("dnode_t",
216 0, dnode_cons
, dnode_dest
, NULL
, NULL
, NULL
, 0);
217 kmem_cache_set_move(dnode_cache
, dnode_move
);
223 kmem_cache_destroy(dnode_cache
);
230 dnode_verify(dnode_t
*dn
)
232 int drop_struct_lock
= FALSE
;
235 ASSERT(dn
->dn_objset
);
236 ASSERT(dn
->dn_handle
->dnh_dnode
== dn
);
238 ASSERT(DMU_OT_IS_VALID(dn
->dn_phys
->dn_type
));
240 if (!(zfs_flags
& ZFS_DEBUG_DNODE_VERIFY
))
243 if (!RW_WRITE_HELD(&dn
->dn_struct_rwlock
)) {
244 rw_enter(&dn
->dn_struct_rwlock
, RW_READER
);
245 drop_struct_lock
= TRUE
;
247 if (dn
->dn_phys
->dn_type
!= DMU_OT_NONE
|| dn
->dn_allocated_txg
!= 0) {
249 ASSERT3U(dn
->dn_indblkshift
, >=, 0);
250 ASSERT3U(dn
->dn_indblkshift
, <=, SPA_MAXBLOCKSHIFT
);
251 if (dn
->dn_datablkshift
) {
252 ASSERT3U(dn
->dn_datablkshift
, >=, SPA_MINBLOCKSHIFT
);
253 ASSERT3U(dn
->dn_datablkshift
, <=, SPA_MAXBLOCKSHIFT
);
254 ASSERT3U(1<<dn
->dn_datablkshift
, ==, dn
->dn_datablksz
);
256 ASSERT3U(dn
->dn_nlevels
, <=, 30);
257 ASSERT(DMU_OT_IS_VALID(dn
->dn_type
));
258 ASSERT3U(dn
->dn_nblkptr
, >=, 1);
259 ASSERT3U(dn
->dn_nblkptr
, <=, DN_MAX_NBLKPTR
);
260 ASSERT3U(dn
->dn_bonuslen
, <=, DN_MAX_BONUSLEN
);
261 ASSERT3U(dn
->dn_datablksz
, ==,
262 dn
->dn_datablkszsec
<< SPA_MINBLOCKSHIFT
);
263 ASSERT3U(ISP2(dn
->dn_datablksz
), ==, dn
->dn_datablkshift
!= 0);
264 ASSERT3U((dn
->dn_nblkptr
- 1) * sizeof (blkptr_t
) +
265 dn
->dn_bonuslen
, <=, DN_MAX_BONUSLEN
);
266 for (i
= 0; i
< TXG_SIZE
; i
++) {
267 ASSERT3U(dn
->dn_next_nlevels
[i
], <=, dn
->dn_nlevels
);
270 if (dn
->dn_phys
->dn_type
!= DMU_OT_NONE
)
271 ASSERT3U(dn
->dn_phys
->dn_nlevels
, <=, dn
->dn_nlevels
);
272 ASSERT(DMU_OBJECT_IS_SPECIAL(dn
->dn_object
) || dn
->dn_dbuf
!= NULL
);
273 if (dn
->dn_dbuf
!= NULL
) {
274 ASSERT3P(dn
->dn_phys
, ==,
275 (dnode_phys_t
*)dn
->dn_dbuf
->db
.db_data
+
276 (dn
->dn_object
% (dn
->dn_dbuf
->db
.db_size
>> DNODE_SHIFT
)));
278 if (drop_struct_lock
)
279 rw_exit(&dn
->dn_struct_rwlock
);
284 dnode_byteswap(dnode_phys_t
*dnp
)
286 uint64_t *buf64
= (void*)&dnp
->dn_blkptr
;
289 if (dnp
->dn_type
== DMU_OT_NONE
) {
290 bzero(dnp
, sizeof (dnode_phys_t
));
294 dnp
->dn_datablkszsec
= BSWAP_16(dnp
->dn_datablkszsec
);
295 dnp
->dn_bonuslen
= BSWAP_16(dnp
->dn_bonuslen
);
296 dnp
->dn_maxblkid
= BSWAP_64(dnp
->dn_maxblkid
);
297 dnp
->dn_used
= BSWAP_64(dnp
->dn_used
);
300 * dn_nblkptr is only one byte, so it's OK to read it in either
301 * byte order. We can't read dn_bouslen.
303 ASSERT(dnp
->dn_indblkshift
<= SPA_MAXBLOCKSHIFT
);
304 ASSERT(dnp
->dn_nblkptr
<= DN_MAX_NBLKPTR
);
305 for (i
= 0; i
< dnp
->dn_nblkptr
* sizeof (blkptr_t
)/8; i
++)
306 buf64
[i
] = BSWAP_64(buf64
[i
]);
309 * OK to check dn_bonuslen for zero, because it won't matter if
310 * we have the wrong byte order. This is necessary because the
311 * dnode dnode is smaller than a regular dnode.
313 if (dnp
->dn_bonuslen
!= 0) {
315 * Note that the bonus length calculated here may be
316 * longer than the actual bonus buffer. This is because
317 * we always put the bonus buffer after the last block
318 * pointer (instead of packing it against the end of the
321 int off
= (dnp
->dn_nblkptr
-1) * sizeof (blkptr_t
);
322 size_t len
= DN_MAX_BONUSLEN
- off
;
323 ASSERT(DMU_OT_IS_VALID(dnp
->dn_bonustype
));
324 dmu_object_byteswap_t byteswap
=
325 DMU_OT_BYTESWAP(dnp
->dn_bonustype
);
326 dmu_ot_byteswap
[byteswap
].ob_func(dnp
->dn_bonus
+ off
, len
);
329 /* Swap SPILL block if we have one */
330 if (dnp
->dn_flags
& DNODE_FLAG_SPILL_BLKPTR
)
331 byteswap_uint64_array(&dnp
->dn_spill
, sizeof (blkptr_t
));
336 dnode_buf_byteswap(void *vbuf
, size_t size
)
338 dnode_phys_t
*buf
= vbuf
;
341 ASSERT3U(sizeof (dnode_phys_t
), ==, (1<<DNODE_SHIFT
));
342 ASSERT((size
& (sizeof (dnode_phys_t
)-1)) == 0);
344 size
>>= DNODE_SHIFT
;
345 for (i
= 0; i
< size
; i
++) {
352 dnode_setbonuslen(dnode_t
*dn
, int newsize
, dmu_tx_t
*tx
)
354 ASSERT3U(refcount_count(&dn
->dn_holds
), >=, 1);
356 dnode_setdirty(dn
, tx
);
357 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
358 ASSERT3U(newsize
, <=, DN_MAX_BONUSLEN
-
359 (dn
->dn_nblkptr
-1) * sizeof (blkptr_t
));
360 dn
->dn_bonuslen
= newsize
;
362 dn
->dn_next_bonuslen
[tx
->tx_txg
& TXG_MASK
] = DN_ZERO_BONUSLEN
;
364 dn
->dn_next_bonuslen
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_bonuslen
;
365 rw_exit(&dn
->dn_struct_rwlock
);
369 dnode_setbonus_type(dnode_t
*dn
, dmu_object_type_t newtype
, dmu_tx_t
*tx
)
371 ASSERT3U(refcount_count(&dn
->dn_holds
), >=, 1);
372 dnode_setdirty(dn
, tx
);
373 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
374 dn
->dn_bonustype
= newtype
;
375 dn
->dn_next_bonustype
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_bonustype
;
376 rw_exit(&dn
->dn_struct_rwlock
);
380 dnode_rm_spill(dnode_t
*dn
, dmu_tx_t
*tx
)
382 ASSERT3U(refcount_count(&dn
->dn_holds
), >=, 1);
383 ASSERT(RW_WRITE_HELD(&dn
->dn_struct_rwlock
));
384 dnode_setdirty(dn
, tx
);
385 dn
->dn_rm_spillblk
[tx
->tx_txg
&TXG_MASK
] = DN_KILL_SPILLBLK
;
386 dn
->dn_have_spill
= B_FALSE
;
390 dnode_setdblksz(dnode_t
*dn
, int size
)
392 ASSERT0(P2PHASE(size
, SPA_MINBLOCKSIZE
));
393 ASSERT3U(size
, <=, SPA_MAXBLOCKSIZE
);
394 ASSERT3U(size
, >=, SPA_MINBLOCKSIZE
);
395 ASSERT3U(size
>> SPA_MINBLOCKSHIFT
, <,
396 1<<(sizeof (dn
->dn_phys
->dn_datablkszsec
) * 8));
397 dn
->dn_datablksz
= size
;
398 dn
->dn_datablkszsec
= size
>> SPA_MINBLOCKSHIFT
;
399 dn
->dn_datablkshift
= ISP2(size
) ? highbit64(size
- 1) : 0;
403 dnode_create(objset_t
*os
, dnode_phys_t
*dnp
, dmu_buf_impl_t
*db
,
404 uint64_t object
, dnode_handle_t
*dnh
)
408 dn
= kmem_cache_alloc(dnode_cache
, KM_SLEEP
);
409 ASSERT(!POINTER_IS_VALID(dn
->dn_objset
));
413 * Defer setting dn_objset until the dnode is ready to be a candidate
414 * for the dnode_move() callback.
416 dn
->dn_object
= object
;
421 if (dnp
->dn_datablkszsec
) {
422 dnode_setdblksz(dn
, dnp
->dn_datablkszsec
<< SPA_MINBLOCKSHIFT
);
424 dn
->dn_datablksz
= 0;
425 dn
->dn_datablkszsec
= 0;
426 dn
->dn_datablkshift
= 0;
428 dn
->dn_indblkshift
= dnp
->dn_indblkshift
;
429 dn
->dn_nlevels
= dnp
->dn_nlevels
;
430 dn
->dn_type
= dnp
->dn_type
;
431 dn
->dn_nblkptr
= dnp
->dn_nblkptr
;
432 dn
->dn_checksum
= dnp
->dn_checksum
;
433 dn
->dn_compress
= dnp
->dn_compress
;
434 dn
->dn_bonustype
= dnp
->dn_bonustype
;
435 dn
->dn_bonuslen
= dnp
->dn_bonuslen
;
436 dn
->dn_maxblkid
= dnp
->dn_maxblkid
;
437 dn
->dn_have_spill
= ((dnp
->dn_flags
& DNODE_FLAG_SPILL_BLKPTR
) != 0);
440 dmu_zfetch_init(&dn
->dn_zfetch
, dn
);
442 ASSERT(DMU_OT_IS_VALID(dn
->dn_phys
->dn_type
));
444 mutex_enter(&os
->os_lock
);
445 if (dnh
->dnh_dnode
!= NULL
) {
446 /* Lost the allocation race. */
447 mutex_exit(&os
->os_lock
);
448 kmem_cache_free(dnode_cache
, dn
);
449 return (dnh
->dnh_dnode
);
453 * Exclude special dnodes from os_dnodes so an empty os_dnodes
454 * signifies that the special dnodes have no references from
455 * their children (the entries in os_dnodes). This allows
456 * dnode_destroy() to easily determine if the last child has
457 * been removed and then complete eviction of the objset.
459 if (!DMU_OBJECT_IS_SPECIAL(object
))
460 list_insert_head(&os
->os_dnodes
, dn
);
464 * Everything else must be valid before assigning dn_objset
465 * makes the dnode eligible for dnode_move().
470 mutex_exit(&os
->os_lock
);
472 arc_space_consume(sizeof (dnode_t
), ARC_SPACE_OTHER
);
477 * Caller must be holding the dnode handle, which is released upon return.
480 dnode_destroy(dnode_t
*dn
)
482 objset_t
*os
= dn
->dn_objset
;
483 boolean_t complete_os_eviction
= B_FALSE
;
485 ASSERT((dn
->dn_id_flags
& DN_ID_NEW_EXIST
) == 0);
487 mutex_enter(&os
->os_lock
);
488 POINTER_INVALIDATE(&dn
->dn_objset
);
489 if (!DMU_OBJECT_IS_SPECIAL(dn
->dn_object
)) {
490 list_remove(&os
->os_dnodes
, dn
);
491 complete_os_eviction
=
492 list_is_empty(&os
->os_dnodes
) &&
493 list_link_active(&os
->os_evicting_node
);
495 mutex_exit(&os
->os_lock
);
497 /* the dnode can no longer move, so we can release the handle */
498 zrl_remove(&dn
->dn_handle
->dnh_zrlock
);
500 dn
->dn_allocated_txg
= 0;
502 dn
->dn_assigned_txg
= 0;
505 if (dn
->dn_dirtyctx_firstset
!= NULL
) {
506 kmem_free(dn
->dn_dirtyctx_firstset
, 1);
507 dn
->dn_dirtyctx_firstset
= NULL
;
509 if (dn
->dn_bonus
!= NULL
) {
510 mutex_enter(&dn
->dn_bonus
->db_mtx
);
511 dbuf_evict(dn
->dn_bonus
);
516 dn
->dn_have_spill
= B_FALSE
;
524 dn
->dn_unlisted_l0_blkid
= 0;
526 dmu_zfetch_rele(&dn
->dn_zfetch
);
527 kmem_cache_free(dnode_cache
, dn
);
528 arc_space_return(sizeof (dnode_t
), ARC_SPACE_OTHER
);
530 if (complete_os_eviction
)
531 dmu_objset_evict_done(os
);
535 dnode_allocate(dnode_t
*dn
, dmu_object_type_t ot
, int blocksize
, int ibs
,
536 dmu_object_type_t bonustype
, int bonuslen
, dmu_tx_t
*tx
)
540 ASSERT3U(blocksize
, <=,
541 spa_maxblocksize(dmu_objset_spa(dn
->dn_objset
)));
543 blocksize
= 1 << zfs_default_bs
;
545 blocksize
= P2ROUNDUP(blocksize
, SPA_MINBLOCKSIZE
);
548 ibs
= zfs_default_ibs
;
550 ibs
= MIN(MAX(ibs
, DN_MIN_INDBLKSHIFT
), DN_MAX_INDBLKSHIFT
);
552 dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d\n", dn
->dn_objset
,
553 dn
->dn_object
, tx
->tx_txg
, blocksize
, ibs
);
555 ASSERT(dn
->dn_type
== DMU_OT_NONE
);
556 ASSERT(bcmp(dn
->dn_phys
, &dnode_phys_zero
, sizeof (dnode_phys_t
)) == 0);
557 ASSERT(dn
->dn_phys
->dn_type
== DMU_OT_NONE
);
558 ASSERT(ot
!= DMU_OT_NONE
);
559 ASSERT(DMU_OT_IS_VALID(ot
));
560 ASSERT((bonustype
== DMU_OT_NONE
&& bonuslen
== 0) ||
561 (bonustype
== DMU_OT_SA
&& bonuslen
== 0) ||
562 (bonustype
!= DMU_OT_NONE
&& bonuslen
!= 0));
563 ASSERT(DMU_OT_IS_VALID(bonustype
));
564 ASSERT3U(bonuslen
, <=, DN_MAX_BONUSLEN
);
565 ASSERT(dn
->dn_type
== DMU_OT_NONE
);
566 ASSERT0(dn
->dn_maxblkid
);
567 ASSERT0(dn
->dn_allocated_txg
);
568 ASSERT0(dn
->dn_assigned_txg
);
569 ASSERT(refcount_is_zero(&dn
->dn_tx_holds
));
570 ASSERT3U(refcount_count(&dn
->dn_holds
), <=, 1);
571 ASSERT(avl_is_empty(&dn
->dn_dbufs
));
573 for (i
= 0; i
< TXG_SIZE
; i
++) {
574 ASSERT0(dn
->dn_next_nblkptr
[i
]);
575 ASSERT0(dn
->dn_next_nlevels
[i
]);
576 ASSERT0(dn
->dn_next_indblkshift
[i
]);
577 ASSERT0(dn
->dn_next_bonuslen
[i
]);
578 ASSERT0(dn
->dn_next_bonustype
[i
]);
579 ASSERT0(dn
->dn_rm_spillblk
[i
]);
580 ASSERT0(dn
->dn_next_blksz
[i
]);
581 ASSERT(!list_link_active(&dn
->dn_dirty_link
[i
]));
582 ASSERT3P(list_head(&dn
->dn_dirty_records
[i
]), ==, NULL
);
583 ASSERT3P(dn
->dn_free_ranges
[i
], ==, NULL
);
587 dnode_setdblksz(dn
, blocksize
);
588 dn
->dn_indblkshift
= ibs
;
590 if (bonustype
== DMU_OT_SA
) /* Maximize bonus space for SA */
594 ((DN_MAX_BONUSLEN
- bonuslen
) >> SPA_BLKPTRSHIFT
);
595 dn
->dn_bonustype
= bonustype
;
596 dn
->dn_bonuslen
= bonuslen
;
597 dn
->dn_checksum
= ZIO_CHECKSUM_INHERIT
;
598 dn
->dn_compress
= ZIO_COMPRESS_INHERIT
;
602 if (dn
->dn_dirtyctx_firstset
) {
603 kmem_free(dn
->dn_dirtyctx_firstset
, 1);
604 dn
->dn_dirtyctx_firstset
= NULL
;
607 dn
->dn_allocated_txg
= tx
->tx_txg
;
610 dnode_setdirty(dn
, tx
);
611 dn
->dn_next_indblkshift
[tx
->tx_txg
& TXG_MASK
] = ibs
;
612 dn
->dn_next_bonuslen
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_bonuslen
;
613 dn
->dn_next_bonustype
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_bonustype
;
614 dn
->dn_next_blksz
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_datablksz
;
618 dnode_reallocate(dnode_t
*dn
, dmu_object_type_t ot
, int blocksize
,
619 dmu_object_type_t bonustype
, int bonuslen
, dmu_tx_t
*tx
)
623 ASSERT3U(blocksize
, >=, SPA_MINBLOCKSIZE
);
624 ASSERT3U(blocksize
, <=,
625 spa_maxblocksize(dmu_objset_spa(dn
->dn_objset
)));
626 ASSERT0(blocksize
% SPA_MINBLOCKSIZE
);
627 ASSERT(dn
->dn_object
!= DMU_META_DNODE_OBJECT
|| dmu_tx_private_ok(tx
));
628 ASSERT(tx
->tx_txg
!= 0);
629 ASSERT((bonustype
== DMU_OT_NONE
&& bonuslen
== 0) ||
630 (bonustype
!= DMU_OT_NONE
&& bonuslen
!= 0) ||
631 (bonustype
== DMU_OT_SA
&& bonuslen
== 0));
632 ASSERT(DMU_OT_IS_VALID(bonustype
));
633 ASSERT3U(bonuslen
, <=, DN_MAX_BONUSLEN
);
635 /* clean up any unreferenced dbufs */
636 dnode_evict_dbufs(dn
);
640 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
641 dnode_setdirty(dn
, tx
);
642 if (dn
->dn_datablksz
!= blocksize
) {
643 /* change blocksize */
644 ASSERT(dn
->dn_maxblkid
== 0 &&
645 (BP_IS_HOLE(&dn
->dn_phys
->dn_blkptr
[0]) ||
646 dnode_block_freed(dn
, 0)));
647 dnode_setdblksz(dn
, blocksize
);
648 dn
->dn_next_blksz
[tx
->tx_txg
&TXG_MASK
] = blocksize
;
650 if (dn
->dn_bonuslen
!= bonuslen
)
651 dn
->dn_next_bonuslen
[tx
->tx_txg
&TXG_MASK
] = bonuslen
;
653 if (bonustype
== DMU_OT_SA
) /* Maximize bonus space for SA */
656 nblkptr
= 1 + ((DN_MAX_BONUSLEN
- bonuslen
) >> SPA_BLKPTRSHIFT
);
657 if (dn
->dn_bonustype
!= bonustype
)
658 dn
->dn_next_bonustype
[tx
->tx_txg
&TXG_MASK
] = bonustype
;
659 if (dn
->dn_nblkptr
!= nblkptr
)
660 dn
->dn_next_nblkptr
[tx
->tx_txg
&TXG_MASK
] = nblkptr
;
661 if (dn
->dn_phys
->dn_flags
& DNODE_FLAG_SPILL_BLKPTR
) {
662 dbuf_rm_spill(dn
, tx
);
663 dnode_rm_spill(dn
, tx
);
665 rw_exit(&dn
->dn_struct_rwlock
);
670 /* change bonus size and type */
671 mutex_enter(&dn
->dn_mtx
);
672 dn
->dn_bonustype
= bonustype
;
673 dn
->dn_bonuslen
= bonuslen
;
674 dn
->dn_nblkptr
= nblkptr
;
675 dn
->dn_checksum
= ZIO_CHECKSUM_INHERIT
;
676 dn
->dn_compress
= ZIO_COMPRESS_INHERIT
;
677 ASSERT3U(dn
->dn_nblkptr
, <=, DN_MAX_NBLKPTR
);
679 /* fix up the bonus db_size */
681 dn
->dn_bonus
->db
.db_size
=
682 DN_MAX_BONUSLEN
- (dn
->dn_nblkptr
-1) * sizeof (blkptr_t
);
683 ASSERT(dn
->dn_bonuslen
<= dn
->dn_bonus
->db
.db_size
);
686 dn
->dn_allocated_txg
= tx
->tx_txg
;
687 mutex_exit(&dn
->dn_mtx
);
692 uint64_t dms_dnode_invalid
;
693 uint64_t dms_dnode_recheck1
;
694 uint64_t dms_dnode_recheck2
;
695 uint64_t dms_dnode_special
;
696 uint64_t dms_dnode_handle
;
697 uint64_t dms_dnode_rwlock
;
698 uint64_t dms_dnode_active
;
700 #endif /* DNODE_STATS */
703 dnode_move_impl(dnode_t
*odn
, dnode_t
*ndn
)
707 ASSERT(!RW_LOCK_HELD(&odn
->dn_struct_rwlock
));
708 ASSERT(MUTEX_NOT_HELD(&odn
->dn_mtx
));
709 ASSERT(MUTEX_NOT_HELD(&odn
->dn_dbufs_mtx
));
710 ASSERT(!RW_LOCK_HELD(&odn
->dn_zfetch
.zf_rwlock
));
713 ndn
->dn_objset
= odn
->dn_objset
;
714 ndn
->dn_object
= odn
->dn_object
;
715 ndn
->dn_dbuf
= odn
->dn_dbuf
;
716 ndn
->dn_handle
= odn
->dn_handle
;
717 ndn
->dn_phys
= odn
->dn_phys
;
718 ndn
->dn_type
= odn
->dn_type
;
719 ndn
->dn_bonuslen
= odn
->dn_bonuslen
;
720 ndn
->dn_bonustype
= odn
->dn_bonustype
;
721 ndn
->dn_nblkptr
= odn
->dn_nblkptr
;
722 ndn
->dn_checksum
= odn
->dn_checksum
;
723 ndn
->dn_compress
= odn
->dn_compress
;
724 ndn
->dn_nlevels
= odn
->dn_nlevels
;
725 ndn
->dn_indblkshift
= odn
->dn_indblkshift
;
726 ndn
->dn_datablkshift
= odn
->dn_datablkshift
;
727 ndn
->dn_datablkszsec
= odn
->dn_datablkszsec
;
728 ndn
->dn_datablksz
= odn
->dn_datablksz
;
729 ndn
->dn_maxblkid
= odn
->dn_maxblkid
;
730 bcopy(&odn
->dn_next_nblkptr
[0], &ndn
->dn_next_nblkptr
[0],
731 sizeof (odn
->dn_next_nblkptr
));
732 bcopy(&odn
->dn_next_nlevels
[0], &ndn
->dn_next_nlevels
[0],
733 sizeof (odn
->dn_next_nlevels
));
734 bcopy(&odn
->dn_next_indblkshift
[0], &ndn
->dn_next_indblkshift
[0],
735 sizeof (odn
->dn_next_indblkshift
));
736 bcopy(&odn
->dn_next_bonustype
[0], &ndn
->dn_next_bonustype
[0],
737 sizeof (odn
->dn_next_bonustype
));
738 bcopy(&odn
->dn_rm_spillblk
[0], &ndn
->dn_rm_spillblk
[0],
739 sizeof (odn
->dn_rm_spillblk
));
740 bcopy(&odn
->dn_next_bonuslen
[0], &ndn
->dn_next_bonuslen
[0],
741 sizeof (odn
->dn_next_bonuslen
));
742 bcopy(&odn
->dn_next_blksz
[0], &ndn
->dn_next_blksz
[0],
743 sizeof (odn
->dn_next_blksz
));
744 for (i
= 0; i
< TXG_SIZE
; i
++) {
745 list_move_tail(&ndn
->dn_dirty_records
[i
],
746 &odn
->dn_dirty_records
[i
]);
748 bcopy(&odn
->dn_free_ranges
[0], &ndn
->dn_free_ranges
[0],
749 sizeof (odn
->dn_free_ranges
));
750 ndn
->dn_allocated_txg
= odn
->dn_allocated_txg
;
751 ndn
->dn_free_txg
= odn
->dn_free_txg
;
752 ndn
->dn_assigned_txg
= odn
->dn_assigned_txg
;
753 ndn
->dn_dirtyctx
= odn
->dn_dirtyctx
;
754 ndn
->dn_dirtyctx_firstset
= odn
->dn_dirtyctx_firstset
;
755 ASSERT(refcount_count(&odn
->dn_tx_holds
) == 0);
756 refcount_transfer(&ndn
->dn_holds
, &odn
->dn_holds
);
757 ASSERT(avl_is_empty(&ndn
->dn_dbufs
));
758 avl_swap(&ndn
->dn_dbufs
, &odn
->dn_dbufs
);
759 ndn
->dn_dbufs_count
= odn
->dn_dbufs_count
;
760 ndn
->dn_unlisted_l0_blkid
= odn
->dn_unlisted_l0_blkid
;
761 ndn
->dn_bonus
= odn
->dn_bonus
;
762 ndn
->dn_have_spill
= odn
->dn_have_spill
;
763 ndn
->dn_zio
= odn
->dn_zio
;
764 ndn
->dn_oldused
= odn
->dn_oldused
;
765 ndn
->dn_oldflags
= odn
->dn_oldflags
;
766 ndn
->dn_olduid
= odn
->dn_olduid
;
767 ndn
->dn_oldgid
= odn
->dn_oldgid
;
768 ndn
->dn_newuid
= odn
->dn_newuid
;
769 ndn
->dn_newgid
= odn
->dn_newgid
;
770 ndn
->dn_id_flags
= odn
->dn_id_flags
;
771 dmu_zfetch_init(&ndn
->dn_zfetch
, NULL
);
772 list_move_tail(&ndn
->dn_zfetch
.zf_stream
, &odn
->dn_zfetch
.zf_stream
);
773 ndn
->dn_zfetch
.zf_dnode
= odn
->dn_zfetch
.zf_dnode
;
774 ndn
->dn_zfetch
.zf_stream_cnt
= odn
->dn_zfetch
.zf_stream_cnt
;
775 ndn
->dn_zfetch
.zf_alloc_fail
= odn
->dn_zfetch
.zf_alloc_fail
;
778 * Update back pointers. Updating the handle fixes the back pointer of
779 * every descendant dbuf as well as the bonus dbuf.
781 ASSERT(ndn
->dn_handle
->dnh_dnode
== odn
);
782 ndn
->dn_handle
->dnh_dnode
= ndn
;
783 if (ndn
->dn_zfetch
.zf_dnode
== odn
) {
784 ndn
->dn_zfetch
.zf_dnode
= ndn
;
788 * Invalidate the original dnode by clearing all of its back pointers.
791 odn
->dn_handle
= NULL
;
792 avl_create(&odn
->dn_dbufs
, dbuf_compare
, sizeof (dmu_buf_impl_t
),
793 offsetof(dmu_buf_impl_t
, db_link
));
794 odn
->dn_dbufs_count
= 0;
795 odn
->dn_unlisted_l0_blkid
= 0;
796 odn
->dn_bonus
= NULL
;
797 odn
->dn_zfetch
.zf_dnode
= NULL
;
800 * Set the low bit of the objset pointer to ensure that dnode_move()
801 * recognizes the dnode as invalid in any subsequent callback.
803 POINTER_INVALIDATE(&odn
->dn_objset
);
806 * Satisfy the destructor.
808 for (i
= 0; i
< TXG_SIZE
; i
++) {
809 list_create(&odn
->dn_dirty_records
[i
],
810 sizeof (dbuf_dirty_record_t
),
811 offsetof(dbuf_dirty_record_t
, dr_dirty_node
));
812 odn
->dn_free_ranges
[i
] = NULL
;
813 odn
->dn_next_nlevels
[i
] = 0;
814 odn
->dn_next_indblkshift
[i
] = 0;
815 odn
->dn_next_bonustype
[i
] = 0;
816 odn
->dn_rm_spillblk
[i
] = 0;
817 odn
->dn_next_bonuslen
[i
] = 0;
818 odn
->dn_next_blksz
[i
] = 0;
820 odn
->dn_allocated_txg
= 0;
821 odn
->dn_free_txg
= 0;
822 odn
->dn_assigned_txg
= 0;
823 odn
->dn_dirtyctx
= 0;
824 odn
->dn_dirtyctx_firstset
= NULL
;
825 odn
->dn_have_spill
= B_FALSE
;
828 odn
->dn_oldflags
= 0;
833 odn
->dn_id_flags
= 0;
839 odn
->dn_moved
= (uint8_t)-1;
845 dnode_move(void *buf
, void *newbuf
, size_t size
, void *arg
)
847 dnode_t
*odn
= buf
, *ndn
= newbuf
;
853 * The dnode is on the objset's list of known dnodes if the objset
854 * pointer is valid. We set the low bit of the objset pointer when
855 * freeing the dnode to invalidate it, and the memory patterns written
856 * by kmem (baddcafe and deadbeef) set at least one of the two low bits.
857 * A newly created dnode sets the objset pointer last of all to indicate
858 * that the dnode is known and in a valid state to be moved by this
862 if (!POINTER_IS_VALID(os
)) {
863 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_invalid
);
864 return (KMEM_CBRC_DONT_KNOW
);
868 * Ensure that the objset does not go away during the move.
870 rw_enter(&os_lock
, RW_WRITER
);
871 if (os
!= odn
->dn_objset
) {
873 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_recheck1
);
874 return (KMEM_CBRC_DONT_KNOW
);
878 * If the dnode is still valid, then so is the objset. We know that no
879 * valid objset can be freed while we hold os_lock, so we can safely
880 * ensure that the objset remains in use.
882 mutex_enter(&os
->os_lock
);
885 * Recheck the objset pointer in case the dnode was removed just before
886 * acquiring the lock.
888 if (os
!= odn
->dn_objset
) {
889 mutex_exit(&os
->os_lock
);
891 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_recheck2
);
892 return (KMEM_CBRC_DONT_KNOW
);
896 * At this point we know that as long as we hold os->os_lock, the dnode
897 * cannot be freed and fields within the dnode can be safely accessed.
898 * The objset listing this dnode cannot go away as long as this dnode is
902 if (DMU_OBJECT_IS_SPECIAL(odn
->dn_object
)) {
903 mutex_exit(&os
->os_lock
);
904 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_special
);
905 return (KMEM_CBRC_NO
);
907 ASSERT(odn
->dn_dbuf
!= NULL
); /* only "special" dnodes have no parent */
910 * Lock the dnode handle to prevent the dnode from obtaining any new
911 * holds. This also prevents the descendant dbufs and the bonus dbuf
912 * from accessing the dnode, so that we can discount their holds. The
913 * handle is safe to access because we know that while the dnode cannot
914 * go away, neither can its handle. Once we hold dnh_zrlock, we can
915 * safely move any dnode referenced only by dbufs.
917 if (!zrl_tryenter(&odn
->dn_handle
->dnh_zrlock
)) {
918 mutex_exit(&os
->os_lock
);
919 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_handle
);
920 return (KMEM_CBRC_LATER
);
924 * Ensure a consistent view of the dnode's holds and the dnode's dbufs.
925 * We need to guarantee that there is a hold for every dbuf in order to
926 * determine whether the dnode is actively referenced. Falsely matching
927 * a dbuf to an active hold would lead to an unsafe move. It's possible
928 * that a thread already having an active dnode hold is about to add a
929 * dbuf, and we can't compare hold and dbuf counts while the add is in
932 if (!rw_tryenter(&odn
->dn_struct_rwlock
, RW_WRITER
)) {
933 zrl_exit(&odn
->dn_handle
->dnh_zrlock
);
934 mutex_exit(&os
->os_lock
);
935 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_rwlock
);
936 return (KMEM_CBRC_LATER
);
940 * A dbuf may be removed (evicted) without an active dnode hold. In that
941 * case, the dbuf count is decremented under the handle lock before the
942 * dbuf's hold is released. This order ensures that if we count the hold
943 * after the dbuf is removed but before its hold is released, we will
944 * treat the unmatched hold as active and exit safely. If we count the
945 * hold before the dbuf is removed, the hold is discounted, and the
946 * removal is blocked until the move completes.
948 refcount
= refcount_count(&odn
->dn_holds
);
949 ASSERT(refcount
>= 0);
950 dbufs
= odn
->dn_dbufs_count
;
952 /* We can't have more dbufs than dnode holds. */
953 ASSERT3U(dbufs
, <=, refcount
);
954 DTRACE_PROBE3(dnode__move
, dnode_t
*, odn
, int64_t, refcount
,
957 if (refcount
> dbufs
) {
958 rw_exit(&odn
->dn_struct_rwlock
);
959 zrl_exit(&odn
->dn_handle
->dnh_zrlock
);
960 mutex_exit(&os
->os_lock
);
961 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_active
);
962 return (KMEM_CBRC_LATER
);
965 rw_exit(&odn
->dn_struct_rwlock
);
968 * At this point we know that anyone with a hold on the dnode is not
969 * actively referencing it. The dnode is known and in a valid state to
970 * move. We're holding the locks needed to execute the critical section.
972 dnode_move_impl(odn
, ndn
);
974 list_link_replace(&odn
->dn_link
, &ndn
->dn_link
);
975 /* If the dnode was safe to move, the refcount cannot have changed. */
976 ASSERT(refcount
== refcount_count(&ndn
->dn_holds
));
977 ASSERT(dbufs
== ndn
->dn_dbufs_count
);
978 zrl_exit(&ndn
->dn_handle
->dnh_zrlock
); /* handle has moved */
979 mutex_exit(&os
->os_lock
);
981 return (KMEM_CBRC_YES
);
986 dnode_special_close(dnode_handle_t
*dnh
)
988 dnode_t
*dn
= dnh
->dnh_dnode
;
991 * Wait for final references to the dnode to clear. This can
992 * only happen if the arc is asyncronously evicting state that
993 * has a hold on this dnode while we are trying to evict this
996 while (refcount_count(&dn
->dn_holds
) > 0)
998 ASSERT(dn
->dn_dbuf
== NULL
||
999 dmu_buf_get_user(&dn
->dn_dbuf
->db
) == NULL
);
1000 zrl_add(&dnh
->dnh_zrlock
);
1001 dnode_destroy(dn
); /* implicit zrl_remove() */
1002 zrl_destroy(&dnh
->dnh_zrlock
);
1003 dnh
->dnh_dnode
= NULL
;
1007 dnode_special_open(objset_t
*os
, dnode_phys_t
*dnp
, uint64_t object
,
1008 dnode_handle_t
*dnh
)
1012 dn
= dnode_create(os
, dnp
, NULL
, object
, dnh
);
1013 zrl_init(&dnh
->dnh_zrlock
);
1018 dnode_buf_pageout(void *dbu
)
1020 dnode_children_t
*children_dnodes
= dbu
;
1023 for (i
= 0; i
< children_dnodes
->dnc_count
; i
++) {
1024 dnode_handle_t
*dnh
= &children_dnodes
->dnc_children
[i
];
1028 * The dnode handle lock guards against the dnode moving to
1029 * another valid address, so there is no need here to guard
1030 * against changes to or from NULL.
1032 if (dnh
->dnh_dnode
== NULL
) {
1033 zrl_destroy(&dnh
->dnh_zrlock
);
1037 zrl_add(&dnh
->dnh_zrlock
);
1038 dn
= dnh
->dnh_dnode
;
1040 * If there are holds on this dnode, then there should
1041 * be holds on the dnode's containing dbuf as well; thus
1042 * it wouldn't be eligible for eviction and this function
1043 * would not have been called.
1045 ASSERT(refcount_is_zero(&dn
->dn_holds
));
1046 ASSERT(refcount_is_zero(&dn
->dn_tx_holds
));
1048 dnode_destroy(dn
); /* implicit zrl_remove() */
1049 zrl_destroy(&dnh
->dnh_zrlock
);
1050 dnh
->dnh_dnode
= NULL
;
1052 kmem_free(children_dnodes
, sizeof (dnode_children_t
) +
1053 children_dnodes
->dnc_count
* sizeof (dnode_handle_t
));
1058 * EINVAL - invalid object number.
1060 * succeeds even for free dnodes.
1063 dnode_hold_impl(objset_t
*os
, uint64_t object
, int flag
,
1064 void *tag
, dnode_t
**dnp
)
1067 int drop_struct_lock
= FALSE
;
1072 dnode_children_t
*children_dnodes
;
1073 dnode_handle_t
*dnh
;
1076 * If you are holding the spa config lock as writer, you shouldn't
1077 * be asking the DMU to do *anything* unless it's the root pool
1078 * which may require us to read from the root filesystem while
1079 * holding some (not all) of the locks as writer.
1081 ASSERT(spa_config_held(os
->os_spa
, SCL_ALL
, RW_WRITER
) == 0 ||
1082 (spa_is_root(os
->os_spa
) &&
1083 spa_config_held(os
->os_spa
, SCL_STATE
, RW_WRITER
)));
1085 if (object
== DMU_USERUSED_OBJECT
|| object
== DMU_GROUPUSED_OBJECT
) {
1086 dn
= (object
== DMU_USERUSED_OBJECT
) ?
1087 DMU_USERUSED_DNODE(os
) : DMU_GROUPUSED_DNODE(os
);
1089 return (SET_ERROR(ENOENT
));
1091 if ((flag
& DNODE_MUST_BE_ALLOCATED
) && type
== DMU_OT_NONE
)
1092 return (SET_ERROR(ENOENT
));
1093 if ((flag
& DNODE_MUST_BE_FREE
) && type
!= DMU_OT_NONE
)
1094 return (SET_ERROR(EEXIST
));
1096 (void) refcount_add(&dn
->dn_holds
, tag
);
1101 if (object
== 0 || object
>= DN_MAX_OBJECT
)
1102 return (SET_ERROR(EINVAL
));
1104 mdn
= DMU_META_DNODE(os
);
1105 ASSERT(mdn
->dn_object
== DMU_META_DNODE_OBJECT
);
1109 if (!RW_WRITE_HELD(&mdn
->dn_struct_rwlock
)) {
1110 rw_enter(&mdn
->dn_struct_rwlock
, RW_READER
);
1111 drop_struct_lock
= TRUE
;
1114 blk
= dbuf_whichblock(mdn
, 0, object
* sizeof (dnode_phys_t
));
1116 db
= dbuf_hold(mdn
, blk
, FTAG
);
1117 if (drop_struct_lock
)
1118 rw_exit(&mdn
->dn_struct_rwlock
);
1120 return (SET_ERROR(EIO
));
1121 err
= dbuf_read(db
, NULL
, DB_RF_CANFAIL
);
1123 dbuf_rele(db
, FTAG
);
1127 ASSERT3U(db
->db
.db_size
, >=, 1<<DNODE_SHIFT
);
1128 epb
= db
->db
.db_size
>> DNODE_SHIFT
;
1130 idx
= object
& (epb
-1);
1132 ASSERT(DB_DNODE(db
)->dn_type
== DMU_OT_DNODE
);
1133 children_dnodes
= dmu_buf_get_user(&db
->db
);
1134 if (children_dnodes
== NULL
) {
1136 dnode_children_t
*winner
;
1137 children_dnodes
= kmem_zalloc(sizeof (dnode_children_t
) +
1138 epb
* sizeof (dnode_handle_t
), KM_SLEEP
);
1139 children_dnodes
->dnc_count
= epb
;
1140 dnh
= &children_dnodes
->dnc_children
[0];
1141 for (i
= 0; i
< epb
; i
++) {
1142 zrl_init(&dnh
[i
].dnh_zrlock
);
1144 dmu_buf_init_user(&children_dnodes
->dnc_dbu
,
1145 dnode_buf_pageout
, NULL
);
1146 winner
= dmu_buf_set_user(&db
->db
, &children_dnodes
->dnc_dbu
);
1147 if (winner
!= NULL
) {
1149 for (i
= 0; i
< epb
; i
++) {
1150 zrl_destroy(&dnh
[i
].dnh_zrlock
);
1153 kmem_free(children_dnodes
, sizeof (dnode_children_t
) +
1154 epb
* sizeof (dnode_handle_t
));
1155 children_dnodes
= winner
;
1158 ASSERT(children_dnodes
->dnc_count
== epb
);
1160 dnh
= &children_dnodes
->dnc_children
[idx
];
1161 zrl_add(&dnh
->dnh_zrlock
);
1162 dn
= dnh
->dnh_dnode
;
1164 dnode_phys_t
*phys
= (dnode_phys_t
*)db
->db
.db_data
+idx
;
1166 dn
= dnode_create(os
, phys
, db
, object
, dnh
);
1169 mutex_enter(&dn
->dn_mtx
);
1171 if (dn
->dn_free_txg
||
1172 ((flag
& DNODE_MUST_BE_ALLOCATED
) && type
== DMU_OT_NONE
) ||
1173 ((flag
& DNODE_MUST_BE_FREE
) &&
1174 (type
!= DMU_OT_NONE
|| !refcount_is_zero(&dn
->dn_holds
)))) {
1175 mutex_exit(&dn
->dn_mtx
);
1176 zrl_remove(&dnh
->dnh_zrlock
);
1177 dbuf_rele(db
, FTAG
);
1178 return (type
== DMU_OT_NONE
? ENOENT
: EEXIST
);
1180 if (refcount_add(&dn
->dn_holds
, tag
) == 1)
1181 dbuf_add_ref(db
, dnh
);
1182 mutex_exit(&dn
->dn_mtx
);
1184 /* Now we can rely on the hold to prevent the dnode from moving. */
1185 zrl_remove(&dnh
->dnh_zrlock
);
1188 ASSERT3P(dn
->dn_dbuf
, ==, db
);
1189 ASSERT3U(dn
->dn_object
, ==, object
);
1190 dbuf_rele(db
, FTAG
);
1197 * Return held dnode if the object is allocated, NULL if not.
1200 dnode_hold(objset_t
*os
, uint64_t object
, void *tag
, dnode_t
**dnp
)
1202 return (dnode_hold_impl(os
, object
, DNODE_MUST_BE_ALLOCATED
, tag
, dnp
));
1206 * Can only add a reference if there is already at least one
1207 * reference on the dnode. Returns FALSE if unable to add a
1211 dnode_add_ref(dnode_t
*dn
, void *tag
)
1213 mutex_enter(&dn
->dn_mtx
);
1214 if (refcount_is_zero(&dn
->dn_holds
)) {
1215 mutex_exit(&dn
->dn_mtx
);
1218 VERIFY(1 < refcount_add(&dn
->dn_holds
, tag
));
1219 mutex_exit(&dn
->dn_mtx
);
1224 dnode_rele(dnode_t
*dn
, void *tag
)
1226 mutex_enter(&dn
->dn_mtx
);
1227 dnode_rele_and_unlock(dn
, tag
);
1231 dnode_rele_and_unlock(dnode_t
*dn
, void *tag
)
1234 /* Get while the hold prevents the dnode from moving. */
1235 dmu_buf_impl_t
*db
= dn
->dn_dbuf
;
1236 dnode_handle_t
*dnh
= dn
->dn_handle
;
1238 refs
= refcount_remove(&dn
->dn_holds
, tag
);
1239 mutex_exit(&dn
->dn_mtx
);
1242 * It's unsafe to release the last hold on a dnode by dnode_rele() or
1243 * indirectly by dbuf_rele() while relying on the dnode handle to
1244 * prevent the dnode from moving, since releasing the last hold could
1245 * result in the dnode's parent dbuf evicting its dnode handles. For
1246 * that reason anyone calling dnode_rele() or dbuf_rele() without some
1247 * other direct or indirect hold on the dnode must first drop the dnode
1250 ASSERT(refs
> 0 || dnh
->dnh_zrlock
.zr_owner
!= curthread
);
1252 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */
1253 if (refs
== 0 && db
!= NULL
) {
1255 * Another thread could add a hold to the dnode handle in
1256 * dnode_hold_impl() while holding the parent dbuf. Since the
1257 * hold on the parent dbuf prevents the handle from being
1258 * destroyed, the hold on the handle is OK. We can't yet assert
1259 * that the handle has zero references, but that will be
1260 * asserted anyway when the handle gets destroyed.
1267 dnode_setdirty(dnode_t
*dn
, dmu_tx_t
*tx
)
1269 objset_t
*os
= dn
->dn_objset
;
1270 uint64_t txg
= tx
->tx_txg
;
1272 if (DMU_OBJECT_IS_SPECIAL(dn
->dn_object
)) {
1273 dsl_dataset_dirty(os
->os_dsl_dataset
, tx
);
1280 mutex_enter(&dn
->dn_mtx
);
1281 ASSERT(dn
->dn_phys
->dn_type
|| dn
->dn_allocated_txg
);
1282 ASSERT(dn
->dn_free_txg
== 0 || dn
->dn_free_txg
>= txg
);
1283 mutex_exit(&dn
->dn_mtx
);
1287 * Determine old uid/gid when necessary
1289 dmu_objset_userquota_get_ids(dn
, B_TRUE
, tx
);
1291 mutex_enter(&os
->os_lock
);
1294 * If we are already marked dirty, we're done.
1296 if (list_link_active(&dn
->dn_dirty_link
[txg
& TXG_MASK
])) {
1297 mutex_exit(&os
->os_lock
);
1301 ASSERT(!refcount_is_zero(&dn
->dn_holds
) ||
1302 !avl_is_empty(&dn
->dn_dbufs
));
1303 ASSERT(dn
->dn_datablksz
!= 0);
1304 ASSERT0(dn
->dn_next_bonuslen
[txg
&TXG_MASK
]);
1305 ASSERT0(dn
->dn_next_blksz
[txg
&TXG_MASK
]);
1306 ASSERT0(dn
->dn_next_bonustype
[txg
&TXG_MASK
]);
1308 dprintf_ds(os
->os_dsl_dataset
, "obj=%llu txg=%llu\n",
1309 dn
->dn_object
, txg
);
1311 if (dn
->dn_free_txg
> 0 && dn
->dn_free_txg
<= txg
) {
1312 list_insert_tail(&os
->os_free_dnodes
[txg
&TXG_MASK
], dn
);
1314 list_insert_tail(&os
->os_dirty_dnodes
[txg
&TXG_MASK
], dn
);
1317 mutex_exit(&os
->os_lock
);
1320 * The dnode maintains a hold on its containing dbuf as
1321 * long as there are holds on it. Each instantiated child
1322 * dbuf maintains a hold on the dnode. When the last child
1323 * drops its hold, the dnode will drop its hold on the
1324 * containing dbuf. We add a "dirty hold" here so that the
1325 * dnode will hang around after we finish processing its
1328 VERIFY(dnode_add_ref(dn
, (void *)(uintptr_t)tx
->tx_txg
));
1330 (void) dbuf_dirty(dn
->dn_dbuf
, tx
);
1332 dsl_dataset_dirty(os
->os_dsl_dataset
, tx
);
1336 dnode_free(dnode_t
*dn
, dmu_tx_t
*tx
)
1338 int txgoff
= tx
->tx_txg
& TXG_MASK
;
1340 dprintf("dn=%p txg=%llu\n", dn
, tx
->tx_txg
);
1342 /* we should be the only holder... hopefully */
1343 /* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */
1345 mutex_enter(&dn
->dn_mtx
);
1346 if (dn
->dn_type
== DMU_OT_NONE
|| dn
->dn_free_txg
) {
1347 mutex_exit(&dn
->dn_mtx
);
1350 dn
->dn_free_txg
= tx
->tx_txg
;
1351 mutex_exit(&dn
->dn_mtx
);
1354 * If the dnode is already dirty, it needs to be moved from
1355 * the dirty list to the free list.
1357 mutex_enter(&dn
->dn_objset
->os_lock
);
1358 if (list_link_active(&dn
->dn_dirty_link
[txgoff
])) {
1359 list_remove(&dn
->dn_objset
->os_dirty_dnodes
[txgoff
], dn
);
1360 list_insert_tail(&dn
->dn_objset
->os_free_dnodes
[txgoff
], dn
);
1361 mutex_exit(&dn
->dn_objset
->os_lock
);
1363 mutex_exit(&dn
->dn_objset
->os_lock
);
1364 dnode_setdirty(dn
, tx
);
1369 * Try to change the block size for the indicated dnode. This can only
1370 * succeed if there are no blocks allocated or dirty beyond first block
1373 dnode_set_blksz(dnode_t
*dn
, uint64_t size
, int ibs
, dmu_tx_t
*tx
)
1378 ASSERT3U(size
, <=, spa_maxblocksize(dmu_objset_spa(dn
->dn_objset
)));
1380 size
= SPA_MINBLOCKSIZE
;
1382 size
= P2ROUNDUP(size
, SPA_MINBLOCKSIZE
);
1384 if (ibs
== dn
->dn_indblkshift
)
1387 if (size
>> SPA_MINBLOCKSHIFT
== dn
->dn_datablkszsec
&& ibs
== 0)
1390 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
1392 /* Check for any allocated blocks beyond the first */
1393 if (dn
->dn_maxblkid
!= 0)
1396 mutex_enter(&dn
->dn_dbufs_mtx
);
1397 for (db
= avl_first(&dn
->dn_dbufs
); db
!= NULL
;
1398 db
= AVL_NEXT(&dn
->dn_dbufs
, db
)) {
1399 if (db
->db_blkid
!= 0 && db
->db_blkid
!= DMU_BONUS_BLKID
&&
1400 db
->db_blkid
!= DMU_SPILL_BLKID
) {
1401 mutex_exit(&dn
->dn_dbufs_mtx
);
1405 mutex_exit(&dn
->dn_dbufs_mtx
);
1407 if (ibs
&& dn
->dn_nlevels
!= 1)
1410 /* resize the old block */
1411 err
= dbuf_hold_impl(dn
, 0, 0, TRUE
, FALSE
, FTAG
, &db
);
1413 dbuf_new_size(db
, size
, tx
);
1414 else if (err
!= ENOENT
)
1417 dnode_setdblksz(dn
, size
);
1418 dnode_setdirty(dn
, tx
);
1419 dn
->dn_next_blksz
[tx
->tx_txg
&TXG_MASK
] = size
;
1421 dn
->dn_indblkshift
= ibs
;
1422 dn
->dn_next_indblkshift
[tx
->tx_txg
&TXG_MASK
] = ibs
;
1424 /* rele after we have fixed the blocksize in the dnode */
1426 dbuf_rele(db
, FTAG
);
1428 rw_exit(&dn
->dn_struct_rwlock
);
1432 rw_exit(&dn
->dn_struct_rwlock
);
1433 return (SET_ERROR(ENOTSUP
));
1436 /* read-holding callers must not rely on the lock being continuously held */
1438 dnode_new_blkid(dnode_t
*dn
, uint64_t blkid
, dmu_tx_t
*tx
, boolean_t have_read
)
1440 uint64_t txgoff
= tx
->tx_txg
& TXG_MASK
;
1441 int epbs
, new_nlevels
;
1444 ASSERT(blkid
!= DMU_BONUS_BLKID
);
1447 RW_READ_HELD(&dn
->dn_struct_rwlock
) :
1448 RW_WRITE_HELD(&dn
->dn_struct_rwlock
));
1451 * if we have a read-lock, check to see if we need to do any work
1452 * before upgrading to a write-lock.
1455 if (blkid
<= dn
->dn_maxblkid
)
1458 if (!rw_tryupgrade(&dn
->dn_struct_rwlock
)) {
1459 rw_exit(&dn
->dn_struct_rwlock
);
1460 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
1464 if (blkid
<= dn
->dn_maxblkid
)
1467 dn
->dn_maxblkid
= blkid
;
1470 * Compute the number of levels necessary to support the new maxblkid.
1473 epbs
= dn
->dn_indblkshift
- SPA_BLKPTRSHIFT
;
1474 for (sz
= dn
->dn_nblkptr
;
1475 sz
<= blkid
&& sz
>= dn
->dn_nblkptr
; sz
<<= epbs
)
1478 if (new_nlevels
> dn
->dn_nlevels
) {
1479 int old_nlevels
= dn
->dn_nlevels
;
1482 dbuf_dirty_record_t
*new, *dr
, *dr_next
;
1484 dn
->dn_nlevels
= new_nlevels
;
1486 ASSERT3U(new_nlevels
, >, dn
->dn_next_nlevels
[txgoff
]);
1487 dn
->dn_next_nlevels
[txgoff
] = new_nlevels
;
1489 /* dirty the left indirects */
1490 db
= dbuf_hold_level(dn
, old_nlevels
, 0, FTAG
);
1492 new = dbuf_dirty(db
, tx
);
1493 dbuf_rele(db
, FTAG
);
1495 /* transfer the dirty records to the new indirect */
1496 mutex_enter(&dn
->dn_mtx
);
1497 mutex_enter(&new->dt
.di
.dr_mtx
);
1498 list
= &dn
->dn_dirty_records
[txgoff
];
1499 for (dr
= list_head(list
); dr
; dr
= dr_next
) {
1500 dr_next
= list_next(&dn
->dn_dirty_records
[txgoff
], dr
);
1501 if (dr
->dr_dbuf
->db_level
!= new_nlevels
-1 &&
1502 dr
->dr_dbuf
->db_blkid
!= DMU_BONUS_BLKID
&&
1503 dr
->dr_dbuf
->db_blkid
!= DMU_SPILL_BLKID
) {
1504 ASSERT(dr
->dr_dbuf
->db_level
== old_nlevels
-1);
1505 list_remove(&dn
->dn_dirty_records
[txgoff
], dr
);
1506 list_insert_tail(&new->dt
.di
.dr_children
, dr
);
1507 dr
->dr_parent
= new;
1510 mutex_exit(&new->dt
.di
.dr_mtx
);
1511 mutex_exit(&dn
->dn_mtx
);
1516 rw_downgrade(&dn
->dn_struct_rwlock
);
1520 dnode_dirty_l1(dnode_t
*dn
, uint64_t l1blkid
, dmu_tx_t
*tx
)
1522 dmu_buf_impl_t
*db
= dbuf_hold_level(dn
, 1, l1blkid
, FTAG
);
1524 dmu_buf_will_dirty(&db
->db
, tx
);
1525 dbuf_rele(db
, FTAG
);
1530 dnode_free_range(dnode_t
*dn
, uint64_t off
, uint64_t len
, dmu_tx_t
*tx
)
1533 uint64_t blkoff
, blkid
, nblks
;
1534 int blksz
, blkshift
, head
, tail
;
1538 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
1539 blksz
= dn
->dn_datablksz
;
1540 blkshift
= dn
->dn_datablkshift
;
1541 epbs
= dn
->dn_indblkshift
- SPA_BLKPTRSHIFT
;
1543 if (len
== DMU_OBJECT_END
) {
1544 len
= UINT64_MAX
- off
;
1549 * First, block align the region to free:
1552 head
= P2NPHASE(off
, blksz
);
1553 blkoff
= P2PHASE(off
, blksz
);
1554 if ((off
>> blkshift
) > dn
->dn_maxblkid
)
1557 ASSERT(dn
->dn_maxblkid
== 0);
1558 if (off
== 0 && len
>= blksz
) {
1560 * Freeing the whole block; fast-track this request.
1561 * Note that we won't dirty any indirect blocks,
1562 * which is fine because we will be freeing the entire
1563 * file and thus all indirect blocks will be freed
1564 * by free_children().
1569 } else if (off
>= blksz
) {
1570 /* Freeing past end-of-data */
1573 /* Freeing part of the block. */
1575 ASSERT3U(head
, >, 0);
1579 /* zero out any partial block data at the start of the range */
1581 ASSERT3U(blkoff
+ head
, ==, blksz
);
1584 if (dbuf_hold_impl(dn
, 0, dbuf_whichblock(dn
, 0, off
),
1585 TRUE
, FALSE
, FTAG
, &db
) == 0) {
1588 /* don't dirty if it isn't on disk and isn't dirty */
1589 if (db
->db_last_dirty
||
1590 (db
->db_blkptr
&& !BP_IS_HOLE(db
->db_blkptr
))) {
1591 rw_exit(&dn
->dn_struct_rwlock
);
1592 dmu_buf_will_dirty(&db
->db
, tx
);
1593 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
1594 data
= db
->db
.db_data
;
1595 bzero(data
+ blkoff
, head
);
1597 dbuf_rele(db
, FTAG
);
1603 /* If the range was less than one block, we're done */
1607 /* If the remaining range is past end of file, we're done */
1608 if ((off
>> blkshift
) > dn
->dn_maxblkid
)
1611 ASSERT(ISP2(blksz
));
1615 tail
= P2PHASE(len
, blksz
);
1617 ASSERT0(P2PHASE(off
, blksz
));
1618 /* zero out any partial block data at the end of the range */
1622 if (dbuf_hold_impl(dn
, 0, dbuf_whichblock(dn
, 0, off
+len
),
1623 TRUE
, FALSE
, FTAG
, &db
) == 0) {
1624 /* don't dirty if not on disk and not dirty */
1625 if (db
->db_last_dirty
||
1626 (db
->db_blkptr
&& !BP_IS_HOLE(db
->db_blkptr
))) {
1627 rw_exit(&dn
->dn_struct_rwlock
);
1628 dmu_buf_will_dirty(&db
->db
, tx
);
1629 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
1630 bzero(db
->db
.db_data
, tail
);
1632 dbuf_rele(db
, FTAG
);
1637 /* If the range did not include a full block, we are done */
1641 ASSERT(IS_P2ALIGNED(off
, blksz
));
1642 ASSERT(trunc
|| IS_P2ALIGNED(len
, blksz
));
1643 blkid
= off
>> blkshift
;
1644 nblks
= len
>> blkshift
;
1649 * Dirty all the indirect blocks in this range. Note that only
1650 * the first and last indirect blocks can actually be written
1651 * (if they were partially freed) -- they must be dirtied, even if
1652 * they do not exist on disk yet. The interior blocks will
1653 * be freed by free_children(), so they will not actually be written.
1654 * Even though these interior blocks will not be written, we
1655 * dirty them for two reasons:
1657 * - It ensures that the indirect blocks remain in memory until
1658 * syncing context. (They have already been prefetched by
1659 * dmu_tx_hold_free(), so we don't have to worry about reading
1660 * them serially here.)
1662 * - The dirty space accounting will put pressure on the txg sync
1663 * mechanism to begin syncing, and to delay transactions if there
1664 * is a large amount of freeing. Even though these indirect
1665 * blocks will not be written, we could need to write the same
1666 * amount of space if we copy the freed BPs into deadlists.
1668 if (dn
->dn_nlevels
> 1) {
1669 uint64_t first
, last
;
1671 first
= blkid
>> epbs
;
1672 dnode_dirty_l1(dn
, first
, tx
);
1674 last
= dn
->dn_maxblkid
>> epbs
;
1676 last
= (blkid
+ nblks
- 1) >> epbs
;
1678 dnode_dirty_l1(dn
, last
, tx
);
1680 int shift
= dn
->dn_datablkshift
+ dn
->dn_indblkshift
-
1682 for (uint64_t i
= first
+ 1; i
< last
; i
++) {
1684 * Set i to the blockid of the next non-hole
1685 * level-1 indirect block at or after i. Note
1686 * that dnode_next_offset() operates in terms of
1687 * level-0-equivalent bytes.
1689 uint64_t ibyte
= i
<< shift
;
1690 int err
= dnode_next_offset(dn
, DNODE_FIND_HAVELOCK
,
1697 * Normally we should not see an error, either
1698 * from dnode_next_offset() or dbuf_hold_level()
1699 * (except for ESRCH from dnode_next_offset).
1700 * If there is an i/o error, then when we read
1701 * this block in syncing context, it will use
1702 * ZIO_FLAG_MUSTSUCCEED, and thus hang/panic according
1703 * to the "failmode" property. dnode_next_offset()
1704 * doesn't have a flag to indicate MUSTSUCCEED.
1709 dnode_dirty_l1(dn
, i
, tx
);
1715 * Add this range to the dnode range list.
1716 * We will finish up this free operation in the syncing phase.
1718 mutex_enter(&dn
->dn_mtx
);
1719 int txgoff
= tx
->tx_txg
& TXG_MASK
;
1720 if (dn
->dn_free_ranges
[txgoff
] == NULL
) {
1721 dn
->dn_free_ranges
[txgoff
] =
1722 range_tree_create(NULL
, NULL
, &dn
->dn_mtx
);
1724 range_tree_clear(dn
->dn_free_ranges
[txgoff
], blkid
, nblks
);
1725 range_tree_add(dn
->dn_free_ranges
[txgoff
], blkid
, nblks
);
1726 dprintf_dnode(dn
, "blkid=%llu nblks=%llu txg=%llu\n",
1727 blkid
, nblks
, tx
->tx_txg
);
1728 mutex_exit(&dn
->dn_mtx
);
1730 dbuf_free_range(dn
, blkid
, blkid
+ nblks
- 1, tx
);
1731 dnode_setdirty(dn
, tx
);
1734 rw_exit(&dn
->dn_struct_rwlock
);
1738 dnode_spill_freed(dnode_t
*dn
)
1742 mutex_enter(&dn
->dn_mtx
);
1743 for (i
= 0; i
< TXG_SIZE
; i
++) {
1744 if (dn
->dn_rm_spillblk
[i
] == DN_KILL_SPILLBLK
)
1747 mutex_exit(&dn
->dn_mtx
);
1748 return (i
< TXG_SIZE
);
1751 /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */
1753 dnode_block_freed(dnode_t
*dn
, uint64_t blkid
)
1755 void *dp
= spa_get_dsl(dn
->dn_objset
->os_spa
);
1758 if (blkid
== DMU_BONUS_BLKID
)
1762 * If we're in the process of opening the pool, dp will not be
1763 * set yet, but there shouldn't be anything dirty.
1768 if (dn
->dn_free_txg
)
1771 if (blkid
== DMU_SPILL_BLKID
)
1772 return (dnode_spill_freed(dn
));
1774 mutex_enter(&dn
->dn_mtx
);
1775 for (i
= 0; i
< TXG_SIZE
; i
++) {
1776 if (dn
->dn_free_ranges
[i
] != NULL
&&
1777 range_tree_contains(dn
->dn_free_ranges
[i
], blkid
, 1))
1780 mutex_exit(&dn
->dn_mtx
);
1781 return (i
< TXG_SIZE
);
1784 /* call from syncing context when we actually write/free space for this dnode */
1786 dnode_diduse_space(dnode_t
*dn
, int64_t delta
)
1789 dprintf_dnode(dn
, "dn=%p dnp=%p used=%llu delta=%lld\n",
1791 (u_longlong_t
)dn
->dn_phys
->dn_used
,
1794 mutex_enter(&dn
->dn_mtx
);
1795 space
= DN_USED_BYTES(dn
->dn_phys
);
1797 ASSERT3U(space
+ delta
, >=, space
); /* no overflow */
1799 ASSERT3U(space
, >=, -delta
); /* no underflow */
1802 if (spa_version(dn
->dn_objset
->os_spa
) < SPA_VERSION_DNODE_BYTES
) {
1803 ASSERT((dn
->dn_phys
->dn_flags
& DNODE_FLAG_USED_BYTES
) == 0);
1804 ASSERT0(P2PHASE(space
, 1<<DEV_BSHIFT
));
1805 dn
->dn_phys
->dn_used
= space
>> DEV_BSHIFT
;
1807 dn
->dn_phys
->dn_used
= space
;
1808 dn
->dn_phys
->dn_flags
|= DNODE_FLAG_USED_BYTES
;
1810 mutex_exit(&dn
->dn_mtx
);
1814 * Call when we think we're going to write/free space in open context to track
1815 * the amount of memory in use by the currently open txg.
1818 dnode_willuse_space(dnode_t
*dn
, int64_t space
, dmu_tx_t
*tx
)
1820 objset_t
*os
= dn
->dn_objset
;
1821 dsl_dataset_t
*ds
= os
->os_dsl_dataset
;
1822 int64_t aspace
= spa_get_asize(os
->os_spa
, space
);
1825 dsl_dir_willuse_space(ds
->ds_dir
, aspace
, tx
);
1826 dsl_pool_dirty_space(dmu_tx_pool(tx
), space
, tx
);
1829 dmu_tx_willuse_space(tx
, aspace
);
1833 * Scans a block at the indicated "level" looking for a hole or data,
1834 * depending on 'flags'.
1836 * If level > 0, then we are scanning an indirect block looking at its
1837 * pointers. If level == 0, then we are looking at a block of dnodes.
1839 * If we don't find what we are looking for in the block, we return ESRCH.
1840 * Otherwise, return with *offset pointing to the beginning (if searching
1841 * forwards) or end (if searching backwards) of the range covered by the
1842 * block pointer we matched on (or dnode).
1844 * The basic search algorithm used below by dnode_next_offset() is to
1845 * use this function to search up the block tree (widen the search) until
1846 * we find something (i.e., we don't return ESRCH) and then search back
1847 * down the tree (narrow the search) until we reach our original search
1851 dnode_next_offset_level(dnode_t
*dn
, int flags
, uint64_t *offset
,
1852 int lvl
, uint64_t blkfill
, uint64_t txg
)
1854 dmu_buf_impl_t
*db
= NULL
;
1856 uint64_t epbs
= dn
->dn_phys
->dn_indblkshift
- SPA_BLKPTRSHIFT
;
1857 uint64_t epb
= 1ULL << epbs
;
1858 uint64_t minfill
, maxfill
;
1860 int i
, inc
, error
, span
;
1862 dprintf("probing object %llu offset %llx level %d of %u\n",
1863 dn
->dn_object
, *offset
, lvl
, dn
->dn_phys
->dn_nlevels
);
1865 hole
= ((flags
& DNODE_FIND_HOLE
) != 0);
1866 inc
= (flags
& DNODE_FIND_BACKWARDS
) ? -1 : 1;
1867 ASSERT(txg
== 0 || !hole
);
1869 if (lvl
== dn
->dn_phys
->dn_nlevels
) {
1871 epb
= dn
->dn_phys
->dn_nblkptr
;
1872 data
= dn
->dn_phys
->dn_blkptr
;
1874 uint64_t blkid
= dbuf_whichblock(dn
, lvl
, *offset
);
1875 error
= dbuf_hold_impl(dn
, lvl
, blkid
, TRUE
, FALSE
, FTAG
, &db
);
1877 if (error
!= ENOENT
)
1882 * This can only happen when we are searching up
1883 * the block tree for data. We don't really need to
1884 * adjust the offset, as we will just end up looking
1885 * at the pointer to this block in its parent, and its
1886 * going to be unallocated, so we will skip over it.
1888 return (SET_ERROR(ESRCH
));
1890 error
= dbuf_read(db
, NULL
, DB_RF_CANFAIL
| DB_RF_HAVESTRUCT
);
1892 dbuf_rele(db
, FTAG
);
1895 data
= db
->db
.db_data
;
1899 if (db
!= NULL
&& txg
!= 0 && (db
->db_blkptr
== NULL
||
1900 db
->db_blkptr
->blk_birth
<= txg
||
1901 BP_IS_HOLE(db
->db_blkptr
))) {
1903 * This can only happen when we are searching up the tree
1904 * and these conditions mean that we need to keep climbing.
1906 error
= SET_ERROR(ESRCH
);
1907 } else if (lvl
== 0) {
1908 dnode_phys_t
*dnp
= data
;
1910 ASSERT(dn
->dn_type
== DMU_OT_DNODE
);
1912 for (i
= (*offset
>> span
) & (blkfill
- 1);
1913 i
>= 0 && i
< blkfill
; i
+= inc
) {
1914 if ((dnp
[i
].dn_type
== DMU_OT_NONE
) == hole
)
1916 *offset
+= (1ULL << span
) * inc
;
1918 if (i
< 0 || i
== blkfill
)
1919 error
= SET_ERROR(ESRCH
);
1921 blkptr_t
*bp
= data
;
1922 uint64_t start
= *offset
;
1923 span
= (lvl
- 1) * epbs
+ dn
->dn_datablkshift
;
1925 maxfill
= blkfill
<< ((lvl
- 1) * epbs
);
1932 *offset
= *offset
>> span
;
1933 for (i
= BF64_GET(*offset
, 0, epbs
);
1934 i
>= 0 && i
< epb
; i
+= inc
) {
1935 if (BP_GET_FILL(&bp
[i
]) >= minfill
&&
1936 BP_GET_FILL(&bp
[i
]) <= maxfill
&&
1937 (hole
|| bp
[i
].blk_birth
> txg
))
1939 if (inc
> 0 || *offset
> 0)
1942 *offset
= *offset
<< span
;
1944 /* traversing backwards; position offset at the end */
1945 ASSERT3U(*offset
, <=, start
);
1946 *offset
= MIN(*offset
+ (1ULL << span
) - 1, start
);
1947 } else if (*offset
< start
) {
1950 if (i
< 0 || i
>= epb
)
1951 error
= SET_ERROR(ESRCH
);
1955 dbuf_rele(db
, FTAG
);
1961 * Find the next hole, data, or sparse region at or after *offset.
1962 * The value 'blkfill' tells us how many items we expect to find
1963 * in an L0 data block; this value is 1 for normal objects,
1964 * DNODES_PER_BLOCK for the meta dnode, and some fraction of
1965 * DNODES_PER_BLOCK when searching for sparse regions thereof.
1969 * dnode_next_offset(dn, flags, offset, 1, 1, 0);
1970 * Finds the next/previous hole/data in a file.
1971 * Used in dmu_offset_next().
1973 * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg);
1974 * Finds the next free/allocated dnode an objset's meta-dnode.
1975 * Only finds objects that have new contents since txg (ie.
1976 * bonus buffer changes and content removal are ignored).
1977 * Used in dmu_object_next().
1979 * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0);
1980 * Finds the next L2 meta-dnode bp that's at most 1/4 full.
1981 * Used in dmu_object_alloc().
1984 dnode_next_offset(dnode_t
*dn
, int flags
, uint64_t *offset
,
1985 int minlvl
, uint64_t blkfill
, uint64_t txg
)
1987 uint64_t initial_offset
= *offset
;
1991 if (!(flags
& DNODE_FIND_HAVELOCK
))
1992 rw_enter(&dn
->dn_struct_rwlock
, RW_READER
);
1994 if (dn
->dn_phys
->dn_nlevels
== 0) {
1995 error
= SET_ERROR(ESRCH
);
1999 if (dn
->dn_datablkshift
== 0) {
2000 if (*offset
< dn
->dn_datablksz
) {
2001 if (flags
& DNODE_FIND_HOLE
)
2002 *offset
= dn
->dn_datablksz
;
2004 error
= SET_ERROR(ESRCH
);
2009 maxlvl
= dn
->dn_phys
->dn_nlevels
;
2011 for (lvl
= minlvl
; lvl
<= maxlvl
; lvl
++) {
2012 error
= dnode_next_offset_level(dn
,
2013 flags
, offset
, lvl
, blkfill
, txg
);
2018 while (error
== 0 && --lvl
>= minlvl
) {
2019 error
= dnode_next_offset_level(dn
,
2020 flags
, offset
, lvl
, blkfill
, txg
);
2024 * There's always a "virtual hole" at the end of the object, even
2025 * if all BP's which physically exist are non-holes.
2027 if ((flags
& DNODE_FIND_HOLE
) && error
== ESRCH
&& txg
== 0 &&
2028 minlvl
== 1 && blkfill
== 1 && !(flags
& DNODE_FIND_BACKWARDS
)) {
2032 if (error
== 0 && (flags
& DNODE_FIND_BACKWARDS
?
2033 initial_offset
< *offset
: initial_offset
> *offset
))
2034 error
= SET_ERROR(ESRCH
);
2036 if (!(flags
& DNODE_FIND_HAVELOCK
))
2037 rw_exit(&dn
->dn_struct_rwlock
);