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 by Delphix. All rights reserved.
26 #include <sys/zfs_context.h>
28 #include <sys/dnode.h>
30 #include <sys/dmu_impl.h>
31 #include <sys/dmu_tx.h>
32 #include <sys/dmu_objset.h>
33 #include <sys/dsl_dir.h>
34 #include <sys/dsl_dataset.h>
37 #include <sys/dmu_zfetch.h>
39 static int free_range_compar(const void *node1
, const void *node2
);
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 ASSERTV(static dnode_phys_t dnode_phys_zero
);
58 int zfs_default_bs
= SPA_MINBLOCKSHIFT
;
59 int zfs_default_ibs
= DN_MAX_INDBLKSHIFT
;
62 static kmem_cbrc_t
dnode_move(void *, void *, size_t, void *);
67 dnode_cons(void *arg
, void *unused
, int kmflag
)
72 rw_init(&dn
->dn_struct_rwlock
, NULL
, RW_DEFAULT
, NULL
);
73 mutex_init(&dn
->dn_mtx
, NULL
, MUTEX_DEFAULT
, NULL
);
74 mutex_init(&dn
->dn_dbufs_mtx
, NULL
, MUTEX_DEFAULT
, NULL
);
75 cv_init(&dn
->dn_notxholds
, NULL
, CV_DEFAULT
, NULL
);
77 refcount_create(&dn
->dn_holds
);
78 refcount_create(&dn
->dn_tx_holds
);
79 list_link_init(&dn
->dn_link
);
81 bzero(&dn
->dn_next_nblkptr
[0], sizeof (dn
->dn_next_nblkptr
));
82 bzero(&dn
->dn_next_nlevels
[0], sizeof (dn
->dn_next_nlevels
));
83 bzero(&dn
->dn_next_indblkshift
[0], sizeof (dn
->dn_next_indblkshift
));
84 bzero(&dn
->dn_next_bonustype
[0], sizeof (dn
->dn_next_bonustype
));
85 bzero(&dn
->dn_rm_spillblk
[0], sizeof (dn
->dn_rm_spillblk
));
86 bzero(&dn
->dn_next_bonuslen
[0], sizeof (dn
->dn_next_bonuslen
));
87 bzero(&dn
->dn_next_blksz
[0], sizeof (dn
->dn_next_blksz
));
89 for (i
= 0; i
< TXG_SIZE
; i
++) {
90 list_link_init(&dn
->dn_dirty_link
[i
]);
91 avl_create(&dn
->dn_ranges
[i
], free_range_compar
,
92 sizeof (free_range_t
),
93 offsetof(struct free_range
, fr_node
));
94 list_create(&dn
->dn_dirty_records
[i
],
95 sizeof (dbuf_dirty_record_t
),
96 offsetof(dbuf_dirty_record_t
, dr_dirty_node
));
99 dn
->dn_allocated_txg
= 0;
101 dn
->dn_assigned_txg
= 0;
103 dn
->dn_dirtyctx_firstset
= NULL
;
105 dn
->dn_have_spill
= B_FALSE
;
115 dn
->dn_dbufs_count
= 0;
116 list_create(&dn
->dn_dbufs
, sizeof (dmu_buf_impl_t
),
117 offsetof(dmu_buf_impl_t
, db_link
));
125 dnode_dest(void *arg
, void *unused
)
130 rw_destroy(&dn
->dn_struct_rwlock
);
131 mutex_destroy(&dn
->dn_mtx
);
132 mutex_destroy(&dn
->dn_dbufs_mtx
);
133 cv_destroy(&dn
->dn_notxholds
);
134 refcount_destroy(&dn
->dn_holds
);
135 refcount_destroy(&dn
->dn_tx_holds
);
136 ASSERT(!list_link_active(&dn
->dn_link
));
138 for (i
= 0; i
< TXG_SIZE
; i
++) {
139 ASSERT(!list_link_active(&dn
->dn_dirty_link
[i
]));
140 avl_destroy(&dn
->dn_ranges
[i
]);
141 list_destroy(&dn
->dn_dirty_records
[i
]);
142 ASSERT3U(dn
->dn_next_nblkptr
[i
], ==, 0);
143 ASSERT3U(dn
->dn_next_nlevels
[i
], ==, 0);
144 ASSERT3U(dn
->dn_next_indblkshift
[i
], ==, 0);
145 ASSERT3U(dn
->dn_next_bonustype
[i
], ==, 0);
146 ASSERT3U(dn
->dn_rm_spillblk
[i
], ==, 0);
147 ASSERT3U(dn
->dn_next_bonuslen
[i
], ==, 0);
148 ASSERT3U(dn
->dn_next_blksz
[i
], ==, 0);
151 ASSERT3U(dn
->dn_allocated_txg
, ==, 0);
152 ASSERT3U(dn
->dn_free_txg
, ==, 0);
153 ASSERT3U(dn
->dn_assigned_txg
, ==, 0);
154 ASSERT3U(dn
->dn_dirtyctx
, ==, 0);
155 ASSERT3P(dn
->dn_dirtyctx_firstset
, ==, NULL
);
156 ASSERT3P(dn
->dn_bonus
, ==, NULL
);
157 ASSERT(!dn
->dn_have_spill
);
158 ASSERT3P(dn
->dn_zio
, ==, NULL
);
159 ASSERT3U(dn
->dn_oldused
, ==, 0);
160 ASSERT3U(dn
->dn_oldflags
, ==, 0);
161 ASSERT3U(dn
->dn_olduid
, ==, 0);
162 ASSERT3U(dn
->dn_oldgid
, ==, 0);
163 ASSERT3U(dn
->dn_newuid
, ==, 0);
164 ASSERT3U(dn
->dn_newgid
, ==, 0);
165 ASSERT3U(dn
->dn_id_flags
, ==, 0);
167 ASSERT3U(dn
->dn_dbufs_count
, ==, 0);
168 list_destroy(&dn
->dn_dbufs
);
174 ASSERT(dnode_cache
== NULL
);
175 dnode_cache
= kmem_cache_create("dnode_t", sizeof (dnode_t
),
176 0, dnode_cons
, dnode_dest
, NULL
, NULL
, NULL
, KMC_KMEM
);
177 kmem_cache_set_move(dnode_cache
, dnode_move
);
183 kmem_cache_destroy(dnode_cache
);
190 dnode_verify(dnode_t
*dn
)
192 int drop_struct_lock
= FALSE
;
195 ASSERT(dn
->dn_objset
);
196 ASSERT(dn
->dn_handle
->dnh_dnode
== dn
);
198 ASSERT(DMU_OT_IS_VALID(dn
->dn_phys
->dn_type
));
200 if (!(zfs_flags
& ZFS_DEBUG_DNODE_VERIFY
))
203 if (!RW_WRITE_HELD(&dn
->dn_struct_rwlock
)) {
204 rw_enter(&dn
->dn_struct_rwlock
, RW_READER
);
205 drop_struct_lock
= TRUE
;
207 if (dn
->dn_phys
->dn_type
!= DMU_OT_NONE
|| dn
->dn_allocated_txg
!= 0) {
209 ASSERT3U(dn
->dn_indblkshift
, <=, SPA_MAXBLOCKSHIFT
);
210 if (dn
->dn_datablkshift
) {
211 ASSERT3U(dn
->dn_datablkshift
, >=, SPA_MINBLOCKSHIFT
);
212 ASSERT3U(dn
->dn_datablkshift
, <=, SPA_MAXBLOCKSHIFT
);
213 ASSERT3U(1<<dn
->dn_datablkshift
, ==, dn
->dn_datablksz
);
215 ASSERT3U(dn
->dn_nlevels
, <=, 30);
216 ASSERT(DMU_OT_IS_VALID(dn
->dn_type
));
217 ASSERT3U(dn
->dn_nblkptr
, >=, 1);
218 ASSERT3U(dn
->dn_nblkptr
, <=, DN_MAX_NBLKPTR
);
219 ASSERT3U(dn
->dn_bonuslen
, <=, DN_MAX_BONUSLEN
);
220 ASSERT3U(dn
->dn_datablksz
, ==,
221 dn
->dn_datablkszsec
<< SPA_MINBLOCKSHIFT
);
222 ASSERT3U(ISP2(dn
->dn_datablksz
), ==, dn
->dn_datablkshift
!= 0);
223 ASSERT3U((dn
->dn_nblkptr
- 1) * sizeof (blkptr_t
) +
224 dn
->dn_bonuslen
, <=, DN_MAX_BONUSLEN
);
225 for (i
= 0; i
< TXG_SIZE
; i
++) {
226 ASSERT3U(dn
->dn_next_nlevels
[i
], <=, dn
->dn_nlevels
);
229 if (dn
->dn_phys
->dn_type
!= DMU_OT_NONE
)
230 ASSERT3U(dn
->dn_phys
->dn_nlevels
, <=, dn
->dn_nlevels
);
231 ASSERT(DMU_OBJECT_IS_SPECIAL(dn
->dn_object
) || dn
->dn_dbuf
!= NULL
);
232 if (dn
->dn_dbuf
!= NULL
) {
233 ASSERT3P(dn
->dn_phys
, ==,
234 (dnode_phys_t
*)dn
->dn_dbuf
->db
.db_data
+
235 (dn
->dn_object
% (dn
->dn_dbuf
->db
.db_size
>> DNODE_SHIFT
)));
237 if (drop_struct_lock
)
238 rw_exit(&dn
->dn_struct_rwlock
);
243 dnode_byteswap(dnode_phys_t
*dnp
)
245 uint64_t *buf64
= (void*)&dnp
->dn_blkptr
;
248 if (dnp
->dn_type
== DMU_OT_NONE
) {
249 bzero(dnp
, sizeof (dnode_phys_t
));
253 dnp
->dn_datablkszsec
= BSWAP_16(dnp
->dn_datablkszsec
);
254 dnp
->dn_bonuslen
= BSWAP_16(dnp
->dn_bonuslen
);
255 dnp
->dn_maxblkid
= BSWAP_64(dnp
->dn_maxblkid
);
256 dnp
->dn_used
= BSWAP_64(dnp
->dn_used
);
259 * dn_nblkptr is only one byte, so it's OK to read it in either
260 * byte order. We can't read dn_bouslen.
262 ASSERT(dnp
->dn_indblkshift
<= SPA_MAXBLOCKSHIFT
);
263 ASSERT(dnp
->dn_nblkptr
<= DN_MAX_NBLKPTR
);
264 for (i
= 0; i
< dnp
->dn_nblkptr
* sizeof (blkptr_t
)/8; i
++)
265 buf64
[i
] = BSWAP_64(buf64
[i
]);
268 * OK to check dn_bonuslen for zero, because it won't matter if
269 * we have the wrong byte order. This is necessary because the
270 * dnode dnode is smaller than a regular dnode.
272 if (dnp
->dn_bonuslen
!= 0) {
274 * Note that the bonus length calculated here may be
275 * longer than the actual bonus buffer. This is because
276 * we always put the bonus buffer after the last block
277 * pointer (instead of packing it against the end of the
280 int off
= (dnp
->dn_nblkptr
-1) * sizeof (blkptr_t
);
281 size_t len
= DN_MAX_BONUSLEN
- off
;
282 dmu_object_byteswap_t byteswap
;
283 ASSERT(DMU_OT_IS_VALID(dnp
->dn_bonustype
));
284 byteswap
= DMU_OT_BYTESWAP(dnp
->dn_bonustype
);
285 dmu_ot_byteswap
[byteswap
].ob_func(dnp
->dn_bonus
+ off
, len
);
288 /* Swap SPILL block if we have one */
289 if (dnp
->dn_flags
& DNODE_FLAG_SPILL_BLKPTR
)
290 byteswap_uint64_array(&dnp
->dn_spill
, sizeof (blkptr_t
));
295 dnode_buf_byteswap(void *vbuf
, size_t size
)
297 dnode_phys_t
*buf
= vbuf
;
300 ASSERT3U(sizeof (dnode_phys_t
), ==, (1<<DNODE_SHIFT
));
301 ASSERT((size
& (sizeof (dnode_phys_t
)-1)) == 0);
303 size
>>= DNODE_SHIFT
;
304 for (i
= 0; i
< size
; i
++) {
311 free_range_compar(const void *node1
, const void *node2
)
313 const free_range_t
*rp1
= node1
;
314 const free_range_t
*rp2
= node2
;
316 if (rp1
->fr_blkid
< rp2
->fr_blkid
)
318 else if (rp1
->fr_blkid
> rp2
->fr_blkid
)
324 dnode_setbonuslen(dnode_t
*dn
, int newsize
, dmu_tx_t
*tx
)
326 ASSERT3U(refcount_count(&dn
->dn_holds
), >=, 1);
328 dnode_setdirty(dn
, tx
);
329 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
330 ASSERT3U(newsize
, <=, DN_MAX_BONUSLEN
-
331 (dn
->dn_nblkptr
-1) * sizeof (blkptr_t
));
332 dn
->dn_bonuslen
= newsize
;
334 dn
->dn_next_bonuslen
[tx
->tx_txg
& TXG_MASK
] = DN_ZERO_BONUSLEN
;
336 dn
->dn_next_bonuslen
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_bonuslen
;
337 rw_exit(&dn
->dn_struct_rwlock
);
341 dnode_setbonus_type(dnode_t
*dn
, dmu_object_type_t newtype
, dmu_tx_t
*tx
)
343 ASSERT3U(refcount_count(&dn
->dn_holds
), >=, 1);
344 dnode_setdirty(dn
, tx
);
345 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
346 dn
->dn_bonustype
= newtype
;
347 dn
->dn_next_bonustype
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_bonustype
;
348 rw_exit(&dn
->dn_struct_rwlock
);
352 dnode_rm_spill(dnode_t
*dn
, dmu_tx_t
*tx
)
354 ASSERT3U(refcount_count(&dn
->dn_holds
), >=, 1);
355 ASSERT(RW_WRITE_HELD(&dn
->dn_struct_rwlock
));
356 dnode_setdirty(dn
, tx
);
357 dn
->dn_rm_spillblk
[tx
->tx_txg
&TXG_MASK
] = DN_KILL_SPILLBLK
;
358 dn
->dn_have_spill
= B_FALSE
;
362 dnode_setdblksz(dnode_t
*dn
, int size
)
364 ASSERT3U(P2PHASE(size
, SPA_MINBLOCKSIZE
), ==, 0);
365 ASSERT3U(size
, <=, SPA_MAXBLOCKSIZE
);
366 ASSERT3U(size
, >=, SPA_MINBLOCKSIZE
);
367 ASSERT3U(size
>> SPA_MINBLOCKSHIFT
, <,
368 1<<(sizeof (dn
->dn_phys
->dn_datablkszsec
) * 8));
369 dn
->dn_datablksz
= size
;
370 dn
->dn_datablkszsec
= size
>> SPA_MINBLOCKSHIFT
;
371 dn
->dn_datablkshift
= ISP2(size
) ? highbit(size
- 1) : 0;
375 dnode_create(objset_t
*os
, dnode_phys_t
*dnp
, dmu_buf_impl_t
*db
,
376 uint64_t object
, dnode_handle_t
*dnh
)
378 dnode_t
*dn
= kmem_cache_alloc(dnode_cache
, KM_PUSHPAGE
);
380 ASSERT(!POINTER_IS_VALID(dn
->dn_objset
));
384 * Defer setting dn_objset until the dnode is ready to be a candidate
385 * for the dnode_move() callback.
387 dn
->dn_object
= object
;
392 if (dnp
->dn_datablkszsec
) {
393 dnode_setdblksz(dn
, dnp
->dn_datablkszsec
<< SPA_MINBLOCKSHIFT
);
395 dn
->dn_datablksz
= 0;
396 dn
->dn_datablkszsec
= 0;
397 dn
->dn_datablkshift
= 0;
399 dn
->dn_indblkshift
= dnp
->dn_indblkshift
;
400 dn
->dn_nlevels
= dnp
->dn_nlevels
;
401 dn
->dn_type
= dnp
->dn_type
;
402 dn
->dn_nblkptr
= dnp
->dn_nblkptr
;
403 dn
->dn_checksum
= dnp
->dn_checksum
;
404 dn
->dn_compress
= dnp
->dn_compress
;
405 dn
->dn_bonustype
= dnp
->dn_bonustype
;
406 dn
->dn_bonuslen
= dnp
->dn_bonuslen
;
407 dn
->dn_maxblkid
= dnp
->dn_maxblkid
;
408 dn
->dn_have_spill
= ((dnp
->dn_flags
& DNODE_FLAG_SPILL_BLKPTR
) != 0);
411 dmu_zfetch_init(&dn
->dn_zfetch
, dn
);
413 ASSERT(DMU_OT_IS_VALID(dn
->dn_phys
->dn_type
));
415 mutex_enter(&os
->os_lock
);
416 list_insert_head(&os
->os_dnodes
, dn
);
419 * Everything else must be valid before assigning dn_objset makes the
420 * dnode eligible for dnode_move().
423 mutex_exit(&os
->os_lock
);
425 arc_space_consume(sizeof (dnode_t
), ARC_SPACE_OTHER
);
430 * Caller must be holding the dnode handle, which is released upon return.
433 dnode_destroy(dnode_t
*dn
)
435 objset_t
*os
= dn
->dn_objset
;
437 ASSERT((dn
->dn_id_flags
& DN_ID_NEW_EXIST
) == 0);
439 mutex_enter(&os
->os_lock
);
440 POINTER_INVALIDATE(&dn
->dn_objset
);
441 list_remove(&os
->os_dnodes
, dn
);
442 mutex_exit(&os
->os_lock
);
444 /* the dnode can no longer move, so we can release the handle */
445 zrl_remove(&dn
->dn_handle
->dnh_zrlock
);
447 dn
->dn_allocated_txg
= 0;
449 dn
->dn_assigned_txg
= 0;
452 if (dn
->dn_dirtyctx_firstset
!= NULL
) {
453 kmem_free(dn
->dn_dirtyctx_firstset
, 1);
454 dn
->dn_dirtyctx_firstset
= NULL
;
456 if (dn
->dn_bonus
!= NULL
) {
457 mutex_enter(&dn
->dn_bonus
->db_mtx
);
458 dbuf_evict(dn
->dn_bonus
);
463 dn
->dn_have_spill
= B_FALSE
;
472 dmu_zfetch_rele(&dn
->dn_zfetch
);
473 kmem_cache_free(dnode_cache
, dn
);
474 arc_space_return(sizeof (dnode_t
), ARC_SPACE_OTHER
);
478 dnode_allocate(dnode_t
*dn
, dmu_object_type_t ot
, int blocksize
, int ibs
,
479 dmu_object_type_t bonustype
, int bonuslen
, dmu_tx_t
*tx
)
484 blocksize
= 1 << zfs_default_bs
;
485 else if (blocksize
> SPA_MAXBLOCKSIZE
)
486 blocksize
= SPA_MAXBLOCKSIZE
;
488 blocksize
= P2ROUNDUP(blocksize
, SPA_MINBLOCKSIZE
);
491 ibs
= zfs_default_ibs
;
493 ibs
= MIN(MAX(ibs
, DN_MIN_INDBLKSHIFT
), DN_MAX_INDBLKSHIFT
);
495 dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d\n", dn
->dn_objset
,
496 dn
->dn_object
, tx
->tx_txg
, blocksize
, ibs
);
498 ASSERT(dn
->dn_type
== DMU_OT_NONE
);
499 ASSERT(bcmp(dn
->dn_phys
, &dnode_phys_zero
, sizeof (dnode_phys_t
)) == 0);
500 ASSERT(dn
->dn_phys
->dn_type
== DMU_OT_NONE
);
501 ASSERT(ot
!= DMU_OT_NONE
);
502 ASSERT(DMU_OT_IS_VALID(ot
));
503 ASSERT((bonustype
== DMU_OT_NONE
&& bonuslen
== 0) ||
504 (bonustype
== DMU_OT_SA
&& bonuslen
== 0) ||
505 (bonustype
!= DMU_OT_NONE
&& bonuslen
!= 0));
506 ASSERT(DMU_OT_IS_VALID(bonustype
));
507 ASSERT3U(bonuslen
, <=, DN_MAX_BONUSLEN
);
508 ASSERT(dn
->dn_type
== DMU_OT_NONE
);
509 ASSERT3U(dn
->dn_maxblkid
, ==, 0);
510 ASSERT3U(dn
->dn_allocated_txg
, ==, 0);
511 ASSERT3U(dn
->dn_assigned_txg
, ==, 0);
512 ASSERT(refcount_is_zero(&dn
->dn_tx_holds
));
513 ASSERT3U(refcount_count(&dn
->dn_holds
), <=, 1);
514 ASSERT3P(list_head(&dn
->dn_dbufs
), ==, NULL
);
516 for (i
= 0; i
< TXG_SIZE
; i
++) {
517 ASSERT3U(dn
->dn_next_nblkptr
[i
], ==, 0);
518 ASSERT3U(dn
->dn_next_nlevels
[i
], ==, 0);
519 ASSERT3U(dn
->dn_next_indblkshift
[i
], ==, 0);
520 ASSERT3U(dn
->dn_next_bonuslen
[i
], ==, 0);
521 ASSERT3U(dn
->dn_next_bonustype
[i
], ==, 0);
522 ASSERT3U(dn
->dn_rm_spillblk
[i
], ==, 0);
523 ASSERT3U(dn
->dn_next_blksz
[i
], ==, 0);
524 ASSERT(!list_link_active(&dn
->dn_dirty_link
[i
]));
525 ASSERT3P(list_head(&dn
->dn_dirty_records
[i
]), ==, NULL
);
526 ASSERT3U(avl_numnodes(&dn
->dn_ranges
[i
]), ==, 0);
530 dnode_setdblksz(dn
, blocksize
);
531 dn
->dn_indblkshift
= ibs
;
533 if (bonustype
== DMU_OT_SA
) /* Maximize bonus space for SA */
537 ((DN_MAX_BONUSLEN
- bonuslen
) >> SPA_BLKPTRSHIFT
);
538 dn
->dn_bonustype
= bonustype
;
539 dn
->dn_bonuslen
= bonuslen
;
540 dn
->dn_checksum
= ZIO_CHECKSUM_INHERIT
;
541 dn
->dn_compress
= ZIO_COMPRESS_INHERIT
;
545 if (dn
->dn_dirtyctx_firstset
) {
546 kmem_free(dn
->dn_dirtyctx_firstset
, 1);
547 dn
->dn_dirtyctx_firstset
= NULL
;
550 dn
->dn_allocated_txg
= tx
->tx_txg
;
553 dnode_setdirty(dn
, tx
);
554 dn
->dn_next_indblkshift
[tx
->tx_txg
& TXG_MASK
] = ibs
;
555 dn
->dn_next_bonuslen
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_bonuslen
;
556 dn
->dn_next_bonustype
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_bonustype
;
557 dn
->dn_next_blksz
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_datablksz
;
561 dnode_reallocate(dnode_t
*dn
, dmu_object_type_t ot
, int blocksize
,
562 dmu_object_type_t bonustype
, int bonuslen
, dmu_tx_t
*tx
)
566 ASSERT3U(blocksize
, >=, SPA_MINBLOCKSIZE
);
567 ASSERT3U(blocksize
, <=, SPA_MAXBLOCKSIZE
);
568 ASSERT3U(blocksize
% SPA_MINBLOCKSIZE
, ==, 0);
569 ASSERT(dn
->dn_object
!= DMU_META_DNODE_OBJECT
|| dmu_tx_private_ok(tx
));
570 ASSERT(tx
->tx_txg
!= 0);
571 ASSERT((bonustype
== DMU_OT_NONE
&& bonuslen
== 0) ||
572 (bonustype
!= DMU_OT_NONE
&& bonuslen
!= 0) ||
573 (bonustype
== DMU_OT_SA
&& bonuslen
== 0));
574 ASSERT(DMU_OT_IS_VALID(bonustype
));
575 ASSERT3U(bonuslen
, <=, DN_MAX_BONUSLEN
);
577 /* clean up any unreferenced dbufs */
578 dnode_evict_dbufs(dn
);
582 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
583 dnode_setdirty(dn
, tx
);
584 if (dn
->dn_datablksz
!= blocksize
) {
585 /* change blocksize */
586 ASSERT(dn
->dn_maxblkid
== 0 &&
587 (BP_IS_HOLE(&dn
->dn_phys
->dn_blkptr
[0]) ||
588 dnode_block_freed(dn
, 0)));
589 dnode_setdblksz(dn
, blocksize
);
590 dn
->dn_next_blksz
[tx
->tx_txg
&TXG_MASK
] = blocksize
;
592 if (dn
->dn_bonuslen
!= bonuslen
)
593 dn
->dn_next_bonuslen
[tx
->tx_txg
&TXG_MASK
] = bonuslen
;
595 if (bonustype
== DMU_OT_SA
) /* Maximize bonus space for SA */
598 nblkptr
= 1 + ((DN_MAX_BONUSLEN
- bonuslen
) >> SPA_BLKPTRSHIFT
);
599 if (dn
->dn_bonustype
!= bonustype
)
600 dn
->dn_next_bonustype
[tx
->tx_txg
&TXG_MASK
] = bonustype
;
601 if (dn
->dn_nblkptr
!= nblkptr
)
602 dn
->dn_next_nblkptr
[tx
->tx_txg
&TXG_MASK
] = nblkptr
;
603 if (dn
->dn_phys
->dn_flags
& DNODE_FLAG_SPILL_BLKPTR
) {
604 dbuf_rm_spill(dn
, tx
);
605 dnode_rm_spill(dn
, tx
);
607 rw_exit(&dn
->dn_struct_rwlock
);
612 /* change bonus size and type */
613 mutex_enter(&dn
->dn_mtx
);
614 dn
->dn_bonustype
= bonustype
;
615 dn
->dn_bonuslen
= bonuslen
;
616 dn
->dn_nblkptr
= nblkptr
;
617 dn
->dn_checksum
= ZIO_CHECKSUM_INHERIT
;
618 dn
->dn_compress
= ZIO_COMPRESS_INHERIT
;
619 ASSERT3U(dn
->dn_nblkptr
, <=, DN_MAX_NBLKPTR
);
621 /* fix up the bonus db_size */
623 dn
->dn_bonus
->db
.db_size
=
624 DN_MAX_BONUSLEN
- (dn
->dn_nblkptr
-1) * sizeof (blkptr_t
);
625 ASSERT(dn
->dn_bonuslen
<= dn
->dn_bonus
->db
.db_size
);
628 dn
->dn_allocated_txg
= tx
->tx_txg
;
629 mutex_exit(&dn
->dn_mtx
);
635 uint64_t dms_dnode_invalid
;
636 uint64_t dms_dnode_recheck1
;
637 uint64_t dms_dnode_recheck2
;
638 uint64_t dms_dnode_special
;
639 uint64_t dms_dnode_handle
;
640 uint64_t dms_dnode_rwlock
;
641 uint64_t dms_dnode_active
;
643 #endif /* DNODE_STATS */
646 dnode_move_impl(dnode_t
*odn
, dnode_t
*ndn
)
650 ASSERT(!RW_LOCK_HELD(&odn
->dn_struct_rwlock
));
651 ASSERT(MUTEX_NOT_HELD(&odn
->dn_mtx
));
652 ASSERT(MUTEX_NOT_HELD(&odn
->dn_dbufs_mtx
));
653 ASSERT(!RW_LOCK_HELD(&odn
->dn_zfetch
.zf_rwlock
));
656 ndn
->dn_objset
= odn
->dn_objset
;
657 ndn
->dn_object
= odn
->dn_object
;
658 ndn
->dn_dbuf
= odn
->dn_dbuf
;
659 ndn
->dn_handle
= odn
->dn_handle
;
660 ndn
->dn_phys
= odn
->dn_phys
;
661 ndn
->dn_type
= odn
->dn_type
;
662 ndn
->dn_bonuslen
= odn
->dn_bonuslen
;
663 ndn
->dn_bonustype
= odn
->dn_bonustype
;
664 ndn
->dn_nblkptr
= odn
->dn_nblkptr
;
665 ndn
->dn_checksum
= odn
->dn_checksum
;
666 ndn
->dn_compress
= odn
->dn_compress
;
667 ndn
->dn_nlevels
= odn
->dn_nlevels
;
668 ndn
->dn_indblkshift
= odn
->dn_indblkshift
;
669 ndn
->dn_datablkshift
= odn
->dn_datablkshift
;
670 ndn
->dn_datablkszsec
= odn
->dn_datablkszsec
;
671 ndn
->dn_datablksz
= odn
->dn_datablksz
;
672 ndn
->dn_maxblkid
= odn
->dn_maxblkid
;
673 bcopy(&odn
->dn_next_nblkptr
[0], &ndn
->dn_next_nblkptr
[0],
674 sizeof (odn
->dn_next_nblkptr
));
675 bcopy(&odn
->dn_next_nlevels
[0], &ndn
->dn_next_nlevels
[0],
676 sizeof (odn
->dn_next_nlevels
));
677 bcopy(&odn
->dn_next_indblkshift
[0], &ndn
->dn_next_indblkshift
[0],
678 sizeof (odn
->dn_next_indblkshift
));
679 bcopy(&odn
->dn_next_bonustype
[0], &ndn
->dn_next_bonustype
[0],
680 sizeof (odn
->dn_next_bonustype
));
681 bcopy(&odn
->dn_rm_spillblk
[0], &ndn
->dn_rm_spillblk
[0],
682 sizeof (odn
->dn_rm_spillblk
));
683 bcopy(&odn
->dn_next_bonuslen
[0], &ndn
->dn_next_bonuslen
[0],
684 sizeof (odn
->dn_next_bonuslen
));
685 bcopy(&odn
->dn_next_blksz
[0], &ndn
->dn_next_blksz
[0],
686 sizeof (odn
->dn_next_blksz
));
687 for (i
= 0; i
< TXG_SIZE
; i
++) {
688 list_move_tail(&ndn
->dn_dirty_records
[i
],
689 &odn
->dn_dirty_records
[i
]);
691 bcopy(&odn
->dn_ranges
[0], &ndn
->dn_ranges
[0], sizeof (odn
->dn_ranges
));
692 ndn
->dn_allocated_txg
= odn
->dn_allocated_txg
;
693 ndn
->dn_free_txg
= odn
->dn_free_txg
;
694 ndn
->dn_assigned_txg
= odn
->dn_assigned_txg
;
695 ndn
->dn_dirtyctx
= odn
->dn_dirtyctx
;
696 ndn
->dn_dirtyctx_firstset
= odn
->dn_dirtyctx_firstset
;
697 ASSERT(refcount_count(&odn
->dn_tx_holds
) == 0);
698 refcount_transfer(&ndn
->dn_holds
, &odn
->dn_holds
);
699 ASSERT(list_is_empty(&ndn
->dn_dbufs
));
700 list_move_tail(&ndn
->dn_dbufs
, &odn
->dn_dbufs
);
701 ndn
->dn_dbufs_count
= odn
->dn_dbufs_count
;
702 ndn
->dn_bonus
= odn
->dn_bonus
;
703 ndn
->dn_have_spill
= odn
->dn_have_spill
;
704 ndn
->dn_zio
= odn
->dn_zio
;
705 ndn
->dn_oldused
= odn
->dn_oldused
;
706 ndn
->dn_oldflags
= odn
->dn_oldflags
;
707 ndn
->dn_olduid
= odn
->dn_olduid
;
708 ndn
->dn_oldgid
= odn
->dn_oldgid
;
709 ndn
->dn_newuid
= odn
->dn_newuid
;
710 ndn
->dn_newgid
= odn
->dn_newgid
;
711 ndn
->dn_id_flags
= odn
->dn_id_flags
;
712 dmu_zfetch_init(&ndn
->dn_zfetch
, NULL
);
713 list_move_tail(&ndn
->dn_zfetch
.zf_stream
, &odn
->dn_zfetch
.zf_stream
);
714 ndn
->dn_zfetch
.zf_dnode
= odn
->dn_zfetch
.zf_dnode
;
715 ndn
->dn_zfetch
.zf_stream_cnt
= odn
->dn_zfetch
.zf_stream_cnt
;
716 ndn
->dn_zfetch
.zf_alloc_fail
= odn
->dn_zfetch
.zf_alloc_fail
;
719 * Update back pointers. Updating the handle fixes the back pointer of
720 * every descendant dbuf as well as the bonus dbuf.
722 ASSERT(ndn
->dn_handle
->dnh_dnode
== odn
);
723 ndn
->dn_handle
->dnh_dnode
= ndn
;
724 if (ndn
->dn_zfetch
.zf_dnode
== odn
) {
725 ndn
->dn_zfetch
.zf_dnode
= ndn
;
729 * Invalidate the original dnode by clearing all of its back pointers.
732 odn
->dn_handle
= NULL
;
733 list_create(&odn
->dn_dbufs
, sizeof (dmu_buf_impl_t
),
734 offsetof(dmu_buf_impl_t
, db_link
));
735 odn
->dn_dbufs_count
= 0;
736 odn
->dn_bonus
= NULL
;
737 odn
->dn_zfetch
.zf_dnode
= NULL
;
740 * Set the low bit of the objset pointer to ensure that dnode_move()
741 * recognizes the dnode as invalid in any subsequent callback.
743 POINTER_INVALIDATE(&odn
->dn_objset
);
746 * Satisfy the destructor.
748 for (i
= 0; i
< TXG_SIZE
; i
++) {
749 list_create(&odn
->dn_dirty_records
[i
],
750 sizeof (dbuf_dirty_record_t
),
751 offsetof(dbuf_dirty_record_t
, dr_dirty_node
));
752 odn
->dn_ranges
[i
].avl_root
= NULL
;
753 odn
->dn_ranges
[i
].avl_numnodes
= 0;
754 odn
->dn_next_nlevels
[i
] = 0;
755 odn
->dn_next_indblkshift
[i
] = 0;
756 odn
->dn_next_bonustype
[i
] = 0;
757 odn
->dn_rm_spillblk
[i
] = 0;
758 odn
->dn_next_bonuslen
[i
] = 0;
759 odn
->dn_next_blksz
[i
] = 0;
761 odn
->dn_allocated_txg
= 0;
762 odn
->dn_free_txg
= 0;
763 odn
->dn_assigned_txg
= 0;
764 odn
->dn_dirtyctx
= 0;
765 odn
->dn_dirtyctx_firstset
= NULL
;
766 odn
->dn_have_spill
= B_FALSE
;
769 odn
->dn_oldflags
= 0;
774 odn
->dn_id_flags
= 0;
780 odn
->dn_moved
= (uint8_t)-1;
785 dnode_move(void *buf
, void *newbuf
, size_t size
, void *arg
)
787 dnode_t
*odn
= buf
, *ndn
= newbuf
;
793 * The dnode is on the objset's list of known dnodes if the objset
794 * pointer is valid. We set the low bit of the objset pointer when
795 * freeing the dnode to invalidate it, and the memory patterns written
796 * by kmem (baddcafe and deadbeef) set at least one of the two low bits.
797 * A newly created dnode sets the objset pointer last of all to indicate
798 * that the dnode is known and in a valid state to be moved by this
802 if (!POINTER_IS_VALID(os
)) {
803 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_invalid
);
804 return (KMEM_CBRC_DONT_KNOW
);
808 * Ensure that the objset does not go away during the move.
810 rw_enter(&os_lock
, RW_WRITER
);
811 if (os
!= odn
->dn_objset
) {
813 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_recheck1
);
814 return (KMEM_CBRC_DONT_KNOW
);
818 * If the dnode is still valid, then so is the objset. We know that no
819 * valid objset can be freed while we hold os_lock, so we can safely
820 * ensure that the objset remains in use.
822 mutex_enter(&os
->os_lock
);
825 * Recheck the objset pointer in case the dnode was removed just before
826 * acquiring the lock.
828 if (os
!= odn
->dn_objset
) {
829 mutex_exit(&os
->os_lock
);
831 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_recheck2
);
832 return (KMEM_CBRC_DONT_KNOW
);
836 * At this point we know that as long as we hold os->os_lock, the dnode
837 * cannot be freed and fields within the dnode can be safely accessed.
838 * The objset listing this dnode cannot go away as long as this dnode is
842 if (DMU_OBJECT_IS_SPECIAL(odn
->dn_object
)) {
843 mutex_exit(&os
->os_lock
);
844 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_special
);
845 return (KMEM_CBRC_NO
);
847 ASSERT(odn
->dn_dbuf
!= NULL
); /* only "special" dnodes have no parent */
850 * Lock the dnode handle to prevent the dnode from obtaining any new
851 * holds. This also prevents the descendant dbufs and the bonus dbuf
852 * from accessing the dnode, so that we can discount their holds. The
853 * handle is safe to access because we know that while the dnode cannot
854 * go away, neither can its handle. Once we hold dnh_zrlock, we can
855 * safely move any dnode referenced only by dbufs.
857 if (!zrl_tryenter(&odn
->dn_handle
->dnh_zrlock
)) {
858 mutex_exit(&os
->os_lock
);
859 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_handle
);
860 return (KMEM_CBRC_LATER
);
864 * Ensure a consistent view of the dnode's holds and the dnode's dbufs.
865 * We need to guarantee that there is a hold for every dbuf in order to
866 * determine whether the dnode is actively referenced. Falsely matching
867 * a dbuf to an active hold would lead to an unsafe move. It's possible
868 * that a thread already having an active dnode hold is about to add a
869 * dbuf, and we can't compare hold and dbuf counts while the add is in
872 if (!rw_tryenter(&odn
->dn_struct_rwlock
, RW_WRITER
)) {
873 zrl_exit(&odn
->dn_handle
->dnh_zrlock
);
874 mutex_exit(&os
->os_lock
);
875 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_rwlock
);
876 return (KMEM_CBRC_LATER
);
880 * A dbuf may be removed (evicted) without an active dnode hold. In that
881 * case, the dbuf count is decremented under the handle lock before the
882 * dbuf's hold is released. This order ensures that if we count the hold
883 * after the dbuf is removed but before its hold is released, we will
884 * treat the unmatched hold as active and exit safely. If we count the
885 * hold before the dbuf is removed, the hold is discounted, and the
886 * removal is blocked until the move completes.
888 refcount
= refcount_count(&odn
->dn_holds
);
889 ASSERT(refcount
>= 0);
890 dbufs
= odn
->dn_dbufs_count
;
892 /* We can't have more dbufs than dnode holds. */
893 ASSERT3U(dbufs
, <=, refcount
);
894 DTRACE_PROBE3(dnode__move
, dnode_t
*, odn
, int64_t, refcount
,
897 if (refcount
> dbufs
) {
898 rw_exit(&odn
->dn_struct_rwlock
);
899 zrl_exit(&odn
->dn_handle
->dnh_zrlock
);
900 mutex_exit(&os
->os_lock
);
901 DNODE_STAT_ADD(dnode_move_stats
.dms_dnode_active
);
902 return (KMEM_CBRC_LATER
);
905 rw_exit(&odn
->dn_struct_rwlock
);
908 * At this point we know that anyone with a hold on the dnode is not
909 * actively referencing it. The dnode is known and in a valid state to
910 * move. We're holding the locks needed to execute the critical section.
912 dnode_move_impl(odn
, ndn
);
914 list_link_replace(&odn
->dn_link
, &ndn
->dn_link
);
915 /* If the dnode was safe to move, the refcount cannot have changed. */
916 ASSERT(refcount
== refcount_count(&ndn
->dn_holds
));
917 ASSERT(dbufs
== ndn
->dn_dbufs_count
);
918 zrl_exit(&ndn
->dn_handle
->dnh_zrlock
); /* handle has moved */
919 mutex_exit(&os
->os_lock
);
921 return (KMEM_CBRC_YES
);
926 dnode_special_close(dnode_handle_t
*dnh
)
928 dnode_t
*dn
= dnh
->dnh_dnode
;
931 * Wait for final references to the dnode to clear. This can
932 * only happen if the arc is asyncronously evicting state that
933 * has a hold on this dnode while we are trying to evict this
936 while (refcount_count(&dn
->dn_holds
) > 0)
938 zrl_add(&dnh
->dnh_zrlock
);
939 dnode_destroy(dn
); /* implicit zrl_remove() */
940 zrl_destroy(&dnh
->dnh_zrlock
);
941 dnh
->dnh_dnode
= NULL
;
945 dnode_special_open(objset_t
*os
, dnode_phys_t
*dnp
, uint64_t object
,
948 dnode_t
*dn
= dnode_create(os
, dnp
, NULL
, object
, dnh
);
950 zrl_init(&dnh
->dnh_zrlock
);
956 dnode_buf_pageout(dmu_buf_t
*db
, void *arg
)
958 dnode_children_t
*children_dnodes
= arg
;
960 int epb
= db
->db_size
>> DNODE_SHIFT
;
962 ASSERT(epb
== children_dnodes
->dnc_count
);
964 for (i
= 0; i
< epb
; i
++) {
965 dnode_handle_t
*dnh
= &children_dnodes
->dnc_children
[i
];
969 * The dnode handle lock guards against the dnode moving to
970 * another valid address, so there is no need here to guard
971 * against changes to or from NULL.
973 if (dnh
->dnh_dnode
== NULL
) {
974 zrl_destroy(&dnh
->dnh_zrlock
);
978 zrl_add(&dnh
->dnh_zrlock
);
981 * If there are holds on this dnode, then there should
982 * be holds on the dnode's containing dbuf as well; thus
983 * it wouldn't be eligible for eviction and this function
984 * would not have been called.
986 ASSERT(refcount_is_zero(&dn
->dn_holds
));
987 ASSERT(refcount_is_zero(&dn
->dn_tx_holds
));
989 dnode_destroy(dn
); /* implicit zrl_remove() */
990 zrl_destroy(&dnh
->dnh_zrlock
);
991 dnh
->dnh_dnode
= NULL
;
993 kmem_free(children_dnodes
, sizeof (dnode_children_t
) +
994 (epb
- 1) * sizeof (dnode_handle_t
));
999 * EINVAL - invalid object number.
1001 * succeeds even for free dnodes.
1004 dnode_hold_impl(objset_t
*os
, uint64_t object
, int flag
,
1005 void *tag
, dnode_t
**dnp
)
1008 int drop_struct_lock
= FALSE
;
1013 dnode_children_t
*children_dnodes
;
1014 dnode_handle_t
*dnh
;
1017 * If you are holding the spa config lock as writer, you shouldn't
1018 * be asking the DMU to do *anything* unless it's the root pool
1019 * which may require us to read from the root filesystem while
1020 * holding some (not all) of the locks as writer.
1022 ASSERT(spa_config_held(os
->os_spa
, SCL_ALL
, RW_WRITER
) == 0 ||
1023 (spa_is_root(os
->os_spa
) &&
1024 spa_config_held(os
->os_spa
, SCL_STATE
, RW_WRITER
)));
1026 if (object
== DMU_USERUSED_OBJECT
|| object
== DMU_GROUPUSED_OBJECT
) {
1027 dn
= (object
== DMU_USERUSED_OBJECT
) ?
1028 DMU_USERUSED_DNODE(os
) : DMU_GROUPUSED_DNODE(os
);
1032 if ((flag
& DNODE_MUST_BE_ALLOCATED
) && type
== DMU_OT_NONE
)
1034 if ((flag
& DNODE_MUST_BE_FREE
) && type
!= DMU_OT_NONE
)
1037 (void) refcount_add(&dn
->dn_holds
, tag
);
1042 if (object
== 0 || object
>= DN_MAX_OBJECT
)
1045 mdn
= DMU_META_DNODE(os
);
1046 ASSERT(mdn
->dn_object
== DMU_META_DNODE_OBJECT
);
1050 if (!RW_WRITE_HELD(&mdn
->dn_struct_rwlock
)) {
1051 rw_enter(&mdn
->dn_struct_rwlock
, RW_READER
);
1052 drop_struct_lock
= TRUE
;
1055 blk
= dbuf_whichblock(mdn
, object
* sizeof (dnode_phys_t
));
1057 db
= dbuf_hold(mdn
, blk
, FTAG
);
1058 if (drop_struct_lock
)
1059 rw_exit(&mdn
->dn_struct_rwlock
);
1062 err
= dbuf_read(db
, NULL
, DB_RF_CANFAIL
);
1064 dbuf_rele(db
, FTAG
);
1068 ASSERT3U(db
->db
.db_size
, >=, 1<<DNODE_SHIFT
);
1069 epb
= db
->db
.db_size
>> DNODE_SHIFT
;
1071 idx
= object
& (epb
-1);
1073 ASSERT(DB_DNODE(db
)->dn_type
== DMU_OT_DNODE
);
1074 children_dnodes
= dmu_buf_get_user(&db
->db
);
1075 if (children_dnodes
== NULL
) {
1077 dnode_children_t
*winner
;
1078 children_dnodes
= kmem_alloc(sizeof (dnode_children_t
) +
1079 (epb
- 1) * sizeof (dnode_handle_t
),
1080 KM_PUSHPAGE
| KM_NODEBUG
);
1081 children_dnodes
->dnc_count
= epb
;
1082 dnh
= &children_dnodes
->dnc_children
[0];
1083 for (i
= 0; i
< epb
; i
++) {
1084 zrl_init(&dnh
[i
].dnh_zrlock
);
1085 dnh
[i
].dnh_dnode
= NULL
;
1087 if ((winner
= dmu_buf_set_user(&db
->db
, children_dnodes
, NULL
,
1088 dnode_buf_pageout
))) {
1089 kmem_free(children_dnodes
, sizeof (dnode_children_t
) +
1090 (epb
- 1) * sizeof (dnode_handle_t
));
1091 children_dnodes
= winner
;
1094 ASSERT(children_dnodes
->dnc_count
== epb
);
1096 dnh
= &children_dnodes
->dnc_children
[idx
];
1097 zrl_add(&dnh
->dnh_zrlock
);
1098 if ((dn
= dnh
->dnh_dnode
) == NULL
) {
1099 dnode_phys_t
*phys
= (dnode_phys_t
*)db
->db
.db_data
+idx
;
1102 dn
= dnode_create(os
, phys
, db
, object
, dnh
);
1103 winner
= atomic_cas_ptr(&dnh
->dnh_dnode
, NULL
, dn
);
1104 if (winner
!= NULL
) {
1105 zrl_add(&dnh
->dnh_zrlock
);
1106 dnode_destroy(dn
); /* implicit zrl_remove() */
1111 mutex_enter(&dn
->dn_mtx
);
1113 if (dn
->dn_free_txg
||
1114 ((flag
& DNODE_MUST_BE_ALLOCATED
) && type
== DMU_OT_NONE
) ||
1115 ((flag
& DNODE_MUST_BE_FREE
) &&
1116 (type
!= DMU_OT_NONE
|| !refcount_is_zero(&dn
->dn_holds
)))) {
1117 mutex_exit(&dn
->dn_mtx
);
1118 zrl_remove(&dnh
->dnh_zrlock
);
1119 dbuf_rele(db
, FTAG
);
1120 return (type
== DMU_OT_NONE
? ENOENT
: EEXIST
);
1122 mutex_exit(&dn
->dn_mtx
);
1124 if (refcount_add(&dn
->dn_holds
, tag
) == 1)
1125 dbuf_add_ref(db
, dnh
);
1126 /* Now we can rely on the hold to prevent the dnode from moving. */
1127 zrl_remove(&dnh
->dnh_zrlock
);
1130 ASSERT3P(dn
->dn_dbuf
, ==, db
);
1131 ASSERT3U(dn
->dn_object
, ==, object
);
1132 dbuf_rele(db
, FTAG
);
1139 * Return held dnode if the object is allocated, NULL if not.
1142 dnode_hold(objset_t
*os
, uint64_t object
, void *tag
, dnode_t
**dnp
)
1144 return (dnode_hold_impl(os
, object
, DNODE_MUST_BE_ALLOCATED
, tag
, dnp
));
1148 * Can only add a reference if there is already at least one
1149 * reference on the dnode. Returns FALSE if unable to add a
1153 dnode_add_ref(dnode_t
*dn
, void *tag
)
1155 mutex_enter(&dn
->dn_mtx
);
1156 if (refcount_is_zero(&dn
->dn_holds
)) {
1157 mutex_exit(&dn
->dn_mtx
);
1160 VERIFY(1 < refcount_add(&dn
->dn_holds
, tag
));
1161 mutex_exit(&dn
->dn_mtx
);
1166 dnode_rele(dnode_t
*dn
, void *tag
)
1169 /* Get while the hold prevents the dnode from moving. */
1170 dmu_buf_impl_t
*db
= dn
->dn_dbuf
;
1171 dnode_handle_t
*dnh
= dn
->dn_handle
;
1173 mutex_enter(&dn
->dn_mtx
);
1174 refs
= refcount_remove(&dn
->dn_holds
, tag
);
1175 mutex_exit(&dn
->dn_mtx
);
1178 * It's unsafe to release the last hold on a dnode by dnode_rele() or
1179 * indirectly by dbuf_rele() while relying on the dnode handle to
1180 * prevent the dnode from moving, since releasing the last hold could
1181 * result in the dnode's parent dbuf evicting its dnode handles. For
1182 * that reason anyone calling dnode_rele() or dbuf_rele() without some
1183 * other direct or indirect hold on the dnode must first drop the dnode
1186 ASSERT(refs
> 0 || dnh
->dnh_zrlock
.zr_owner
!= curthread
);
1188 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */
1189 if (refs
== 0 && db
!= NULL
) {
1191 * Another thread could add a hold to the dnode handle in
1192 * dnode_hold_impl() while holding the parent dbuf. Since the
1193 * hold on the parent dbuf prevents the handle from being
1194 * destroyed, the hold on the handle is OK. We can't yet assert
1195 * that the handle has zero references, but that will be
1196 * asserted anyway when the handle gets destroyed.
1203 dnode_setdirty(dnode_t
*dn
, dmu_tx_t
*tx
)
1205 objset_t
*os
= dn
->dn_objset
;
1206 uint64_t txg
= tx
->tx_txg
;
1208 if (DMU_OBJECT_IS_SPECIAL(dn
->dn_object
)) {
1209 dsl_dataset_dirty(os
->os_dsl_dataset
, tx
);
1216 mutex_enter(&dn
->dn_mtx
);
1217 ASSERT(dn
->dn_phys
->dn_type
|| dn
->dn_allocated_txg
);
1218 ASSERT(dn
->dn_free_txg
== 0 || dn
->dn_free_txg
>= txg
);
1219 mutex_exit(&dn
->dn_mtx
);
1223 * Determine old uid/gid when necessary
1225 dmu_objset_userquota_get_ids(dn
, B_TRUE
, tx
);
1227 mutex_enter(&os
->os_lock
);
1230 * If we are already marked dirty, we're done.
1232 if (list_link_active(&dn
->dn_dirty_link
[txg
& TXG_MASK
])) {
1233 mutex_exit(&os
->os_lock
);
1237 ASSERT(!refcount_is_zero(&dn
->dn_holds
) || list_head(&dn
->dn_dbufs
));
1238 ASSERT(dn
->dn_datablksz
!= 0);
1239 ASSERT3U(dn
->dn_next_bonuslen
[txg
&TXG_MASK
], ==, 0);
1240 ASSERT3U(dn
->dn_next_blksz
[txg
&TXG_MASK
], ==, 0);
1241 ASSERT3U(dn
->dn_next_bonustype
[txg
&TXG_MASK
], ==, 0);
1243 dprintf_ds(os
->os_dsl_dataset
, "obj=%llu txg=%llu\n",
1244 dn
->dn_object
, txg
);
1246 if (dn
->dn_free_txg
> 0 && dn
->dn_free_txg
<= txg
) {
1247 list_insert_tail(&os
->os_free_dnodes
[txg
&TXG_MASK
], dn
);
1249 list_insert_tail(&os
->os_dirty_dnodes
[txg
&TXG_MASK
], dn
);
1252 mutex_exit(&os
->os_lock
);
1255 * The dnode maintains a hold on its containing dbuf as
1256 * long as there are holds on it. Each instantiated child
1257 * dbuf maintains a hold on the dnode. When the last child
1258 * drops its hold, the dnode will drop its hold on the
1259 * containing dbuf. We add a "dirty hold" here so that the
1260 * dnode will hang around after we finish processing its
1263 VERIFY(dnode_add_ref(dn
, (void *)(uintptr_t)tx
->tx_txg
));
1265 (void) dbuf_dirty(dn
->dn_dbuf
, tx
);
1267 dsl_dataset_dirty(os
->os_dsl_dataset
, tx
);
1271 dnode_free(dnode_t
*dn
, dmu_tx_t
*tx
)
1273 int txgoff
= tx
->tx_txg
& TXG_MASK
;
1275 dprintf("dn=%p txg=%llu\n", dn
, tx
->tx_txg
);
1277 /* we should be the only holder... hopefully */
1278 /* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */
1280 mutex_enter(&dn
->dn_mtx
);
1281 if (dn
->dn_type
== DMU_OT_NONE
|| dn
->dn_free_txg
) {
1282 mutex_exit(&dn
->dn_mtx
);
1285 dn
->dn_free_txg
= tx
->tx_txg
;
1286 mutex_exit(&dn
->dn_mtx
);
1289 * If the dnode is already dirty, it needs to be moved from
1290 * the dirty list to the free list.
1292 mutex_enter(&dn
->dn_objset
->os_lock
);
1293 if (list_link_active(&dn
->dn_dirty_link
[txgoff
])) {
1294 list_remove(&dn
->dn_objset
->os_dirty_dnodes
[txgoff
], dn
);
1295 list_insert_tail(&dn
->dn_objset
->os_free_dnodes
[txgoff
], dn
);
1296 mutex_exit(&dn
->dn_objset
->os_lock
);
1298 mutex_exit(&dn
->dn_objset
->os_lock
);
1299 dnode_setdirty(dn
, tx
);
1304 * Try to change the block size for the indicated dnode. This can only
1305 * succeed if there are no blocks allocated or dirty beyond first block
1308 dnode_set_blksz(dnode_t
*dn
, uint64_t size
, int ibs
, dmu_tx_t
*tx
)
1310 dmu_buf_impl_t
*db
, *db_next
;
1314 size
= SPA_MINBLOCKSIZE
;
1315 if (size
> SPA_MAXBLOCKSIZE
)
1316 size
= SPA_MAXBLOCKSIZE
;
1318 size
= P2ROUNDUP(size
, SPA_MINBLOCKSIZE
);
1320 if (ibs
== dn
->dn_indblkshift
)
1323 if (size
>> SPA_MINBLOCKSHIFT
== dn
->dn_datablkszsec
&& ibs
== 0)
1326 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
1328 /* Check for any allocated blocks beyond the first */
1329 if (dn
->dn_phys
->dn_maxblkid
!= 0)
1332 mutex_enter(&dn
->dn_dbufs_mtx
);
1333 for (db
= list_head(&dn
->dn_dbufs
); db
; db
= db_next
) {
1334 db_next
= list_next(&dn
->dn_dbufs
, db
);
1336 if (db
->db_blkid
!= 0 && db
->db_blkid
!= DMU_BONUS_BLKID
&&
1337 db
->db_blkid
!= DMU_SPILL_BLKID
) {
1338 mutex_exit(&dn
->dn_dbufs_mtx
);
1342 mutex_exit(&dn
->dn_dbufs_mtx
);
1344 if (ibs
&& dn
->dn_nlevels
!= 1)
1347 /* resize the old block */
1348 err
= dbuf_hold_impl(dn
, 0, 0, TRUE
, FTAG
, &db
);
1350 dbuf_new_size(db
, size
, tx
);
1351 else if (err
!= ENOENT
)
1354 dnode_setdblksz(dn
, size
);
1355 dnode_setdirty(dn
, tx
);
1356 dn
->dn_next_blksz
[tx
->tx_txg
&TXG_MASK
] = size
;
1358 dn
->dn_indblkshift
= ibs
;
1359 dn
->dn_next_indblkshift
[tx
->tx_txg
&TXG_MASK
] = ibs
;
1361 /* rele after we have fixed the blocksize in the dnode */
1363 dbuf_rele(db
, FTAG
);
1365 rw_exit(&dn
->dn_struct_rwlock
);
1369 rw_exit(&dn
->dn_struct_rwlock
);
1373 /* read-holding callers must not rely on the lock being continuously held */
1375 dnode_new_blkid(dnode_t
*dn
, uint64_t blkid
, dmu_tx_t
*tx
, boolean_t have_read
)
1377 uint64_t txgoff
= tx
->tx_txg
& TXG_MASK
;
1378 int epbs
, new_nlevels
;
1381 ASSERT(blkid
!= DMU_BONUS_BLKID
);
1384 RW_READ_HELD(&dn
->dn_struct_rwlock
) :
1385 RW_WRITE_HELD(&dn
->dn_struct_rwlock
));
1388 * if we have a read-lock, check to see if we need to do any work
1389 * before upgrading to a write-lock.
1392 if (blkid
<= dn
->dn_maxblkid
)
1395 if (!rw_tryupgrade(&dn
->dn_struct_rwlock
)) {
1396 rw_exit(&dn
->dn_struct_rwlock
);
1397 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
1401 if (blkid
<= dn
->dn_maxblkid
)
1404 dn
->dn_maxblkid
= blkid
;
1407 * Compute the number of levels necessary to support the new maxblkid.
1410 epbs
= dn
->dn_indblkshift
- SPA_BLKPTRSHIFT
;
1411 for (sz
= dn
->dn_nblkptr
;
1412 sz
<= blkid
&& sz
>= dn
->dn_nblkptr
; sz
<<= epbs
)
1415 if (new_nlevels
> dn
->dn_nlevels
) {
1416 int old_nlevels
= dn
->dn_nlevels
;
1419 dbuf_dirty_record_t
*new, *dr
, *dr_next
;
1421 dn
->dn_nlevels
= new_nlevels
;
1423 ASSERT3U(new_nlevels
, >, dn
->dn_next_nlevels
[txgoff
]);
1424 dn
->dn_next_nlevels
[txgoff
] = new_nlevels
;
1426 /* dirty the left indirects */
1427 db
= dbuf_hold_level(dn
, old_nlevels
, 0, FTAG
);
1429 new = dbuf_dirty(db
, tx
);
1430 dbuf_rele(db
, FTAG
);
1432 /* transfer the dirty records to the new indirect */
1433 mutex_enter(&dn
->dn_mtx
);
1434 mutex_enter(&new->dt
.di
.dr_mtx
);
1435 list
= &dn
->dn_dirty_records
[txgoff
];
1436 for (dr
= list_head(list
); dr
; dr
= dr_next
) {
1437 dr_next
= list_next(&dn
->dn_dirty_records
[txgoff
], dr
);
1438 if (dr
->dr_dbuf
->db_level
!= new_nlevels
-1 &&
1439 dr
->dr_dbuf
->db_blkid
!= DMU_BONUS_BLKID
&&
1440 dr
->dr_dbuf
->db_blkid
!= DMU_SPILL_BLKID
) {
1441 ASSERT(dr
->dr_dbuf
->db_level
== old_nlevels
-1);
1442 list_remove(&dn
->dn_dirty_records
[txgoff
], dr
);
1443 list_insert_tail(&new->dt
.di
.dr_children
, dr
);
1444 dr
->dr_parent
= new;
1447 mutex_exit(&new->dt
.di
.dr_mtx
);
1448 mutex_exit(&dn
->dn_mtx
);
1453 rw_downgrade(&dn
->dn_struct_rwlock
);
1457 dnode_clear_range(dnode_t
*dn
, uint64_t blkid
, uint64_t nblks
, dmu_tx_t
*tx
)
1459 avl_tree_t
*tree
= &dn
->dn_ranges
[tx
->tx_txg
&TXG_MASK
];
1462 free_range_t rp_tofind
;
1463 uint64_t endblk
= blkid
+ nblks
;
1465 ASSERT(MUTEX_HELD(&dn
->dn_mtx
));
1466 ASSERT(nblks
<= UINT64_MAX
- blkid
); /* no overflow */
1468 dprintf_dnode(dn
, "blkid=%llu nblks=%llu txg=%llu\n",
1469 blkid
, nblks
, tx
->tx_txg
);
1470 rp_tofind
.fr_blkid
= blkid
;
1471 rp
= avl_find(tree
, &rp_tofind
, &where
);
1473 rp
= avl_nearest(tree
, where
, AVL_BEFORE
);
1475 rp
= avl_nearest(tree
, where
, AVL_AFTER
);
1477 while (rp
&& (rp
->fr_blkid
<= blkid
+ nblks
)) {
1478 uint64_t fr_endblk
= rp
->fr_blkid
+ rp
->fr_nblks
;
1479 free_range_t
*nrp
= AVL_NEXT(tree
, rp
);
1481 if (blkid
<= rp
->fr_blkid
&& endblk
>= fr_endblk
) {
1482 /* clear this entire range */
1483 avl_remove(tree
, rp
);
1484 kmem_free(rp
, sizeof (free_range_t
));
1485 } else if (blkid
<= rp
->fr_blkid
&&
1486 endblk
> rp
->fr_blkid
&& endblk
< fr_endblk
) {
1487 /* clear the beginning of this range */
1488 rp
->fr_blkid
= endblk
;
1489 rp
->fr_nblks
= fr_endblk
- endblk
;
1490 } else if (blkid
> rp
->fr_blkid
&& blkid
< fr_endblk
&&
1491 endblk
>= fr_endblk
) {
1492 /* clear the end of this range */
1493 rp
->fr_nblks
= blkid
- rp
->fr_blkid
;
1494 } else if (blkid
> rp
->fr_blkid
&& endblk
< fr_endblk
) {
1495 /* clear a chunk out of this range */
1496 free_range_t
*new_rp
=
1497 kmem_alloc(sizeof (free_range_t
), KM_PUSHPAGE
);
1499 new_rp
->fr_blkid
= endblk
;
1500 new_rp
->fr_nblks
= fr_endblk
- endblk
;
1501 avl_insert_here(tree
, new_rp
, rp
, AVL_AFTER
);
1502 rp
->fr_nblks
= blkid
- rp
->fr_blkid
;
1504 /* there may be no overlap */
1510 dnode_free_range(dnode_t
*dn
, uint64_t off
, uint64_t len
, dmu_tx_t
*tx
)
1513 uint64_t blkoff
, blkid
, nblks
;
1514 int blksz
, blkshift
, head
, tail
;
1518 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
1519 blksz
= dn
->dn_datablksz
;
1520 blkshift
= dn
->dn_datablkshift
;
1521 epbs
= dn
->dn_indblkshift
- SPA_BLKPTRSHIFT
;
1524 len
= UINT64_MAX
- off
;
1529 * First, block align the region to free:
1532 head
= P2NPHASE(off
, blksz
);
1533 blkoff
= P2PHASE(off
, blksz
);
1534 if ((off
>> blkshift
) > dn
->dn_maxblkid
)
1537 ASSERT(dn
->dn_maxblkid
== 0);
1538 if (off
== 0 && len
>= blksz
) {
1539 /* Freeing the whole block; fast-track this request */
1543 } else if (off
>= blksz
) {
1544 /* Freeing past end-of-data */
1547 /* Freeing part of the block. */
1549 ASSERT3U(head
, >, 0);
1553 /* zero out any partial block data at the start of the range */
1555 ASSERT3U(blkoff
+ head
, ==, blksz
);
1558 if (dbuf_hold_impl(dn
, 0, dbuf_whichblock(dn
, off
), TRUE
,
1562 /* don't dirty if it isn't on disk and isn't dirty */
1563 if (db
->db_last_dirty
||
1564 (db
->db_blkptr
&& !BP_IS_HOLE(db
->db_blkptr
))) {
1565 rw_exit(&dn
->dn_struct_rwlock
);
1566 dbuf_will_dirty(db
, tx
);
1567 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
1568 data
= db
->db
.db_data
;
1569 bzero(data
+ blkoff
, head
);
1571 dbuf_rele(db
, FTAG
);
1577 /* If the range was less than one block, we're done */
1581 /* If the remaining range is past end of file, we're done */
1582 if ((off
>> blkshift
) > dn
->dn_maxblkid
)
1585 ASSERT(ISP2(blksz
));
1589 tail
= P2PHASE(len
, blksz
);
1591 ASSERT3U(P2PHASE(off
, blksz
), ==, 0);
1592 /* zero out any partial block data at the end of the range */
1596 if (dbuf_hold_impl(dn
, 0, dbuf_whichblock(dn
, off
+len
),
1597 TRUE
, FTAG
, &db
) == 0) {
1598 /* don't dirty if not on disk and not dirty */
1599 if (db
->db_last_dirty
||
1600 (db
->db_blkptr
&& !BP_IS_HOLE(db
->db_blkptr
))) {
1601 rw_exit(&dn
->dn_struct_rwlock
);
1602 dbuf_will_dirty(db
, tx
);
1603 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
1604 bzero(db
->db
.db_data
, tail
);
1606 dbuf_rele(db
, FTAG
);
1611 /* If the range did not include a full block, we are done */
1615 ASSERT(IS_P2ALIGNED(off
, blksz
));
1616 ASSERT(trunc
|| IS_P2ALIGNED(len
, blksz
));
1617 blkid
= off
>> blkshift
;
1618 nblks
= len
>> blkshift
;
1623 * Read in and mark all the level-1 indirects dirty,
1624 * so that they will stay in memory until syncing phase.
1625 * Always dirty the first and last indirect to make sure
1626 * we dirty all the partial indirects.
1628 if (dn
->dn_nlevels
> 1) {
1629 uint64_t i
, first
, last
;
1630 int shift
= epbs
+ dn
->dn_datablkshift
;
1632 first
= blkid
>> epbs
;
1633 if ((db
= dbuf_hold_level(dn
, 1, first
, FTAG
))) {
1634 dbuf_will_dirty(db
, tx
);
1635 dbuf_rele(db
, FTAG
);
1638 last
= dn
->dn_maxblkid
>> epbs
;
1640 last
= (blkid
+ nblks
- 1) >> epbs
;
1641 if (last
> first
&& (db
= dbuf_hold_level(dn
, 1, last
, FTAG
))) {
1642 dbuf_will_dirty(db
, tx
);
1643 dbuf_rele(db
, FTAG
);
1645 for (i
= first
+ 1; i
< last
; i
++) {
1646 uint64_t ibyte
= i
<< shift
;
1649 err
= dnode_next_offset(dn
,
1650 DNODE_FIND_HAVELOCK
, &ibyte
, 1, 1, 0);
1652 if (err
== ESRCH
|| i
>= last
)
1655 db
= dbuf_hold_level(dn
, 1, i
, FTAG
);
1657 dbuf_will_dirty(db
, tx
);
1658 dbuf_rele(db
, FTAG
);
1664 * Add this range to the dnode range list.
1665 * We will finish up this free operation in the syncing phase.
1667 mutex_enter(&dn
->dn_mtx
);
1668 dnode_clear_range(dn
, blkid
, nblks
, tx
);
1670 free_range_t
*rp
, *found
;
1672 avl_tree_t
*tree
= &dn
->dn_ranges
[tx
->tx_txg
&TXG_MASK
];
1674 /* Add new range to dn_ranges */
1675 rp
= kmem_alloc(sizeof (free_range_t
), KM_PUSHPAGE
);
1676 rp
->fr_blkid
= blkid
;
1677 rp
->fr_nblks
= nblks
;
1678 found
= avl_find(tree
, rp
, &where
);
1679 ASSERT(found
== NULL
);
1680 avl_insert(tree
, rp
, where
);
1681 dprintf_dnode(dn
, "blkid=%llu nblks=%llu txg=%llu\n",
1682 blkid
, nblks
, tx
->tx_txg
);
1684 mutex_exit(&dn
->dn_mtx
);
1686 dbuf_free_range(dn
, blkid
, blkid
+ nblks
- 1, tx
);
1687 dnode_setdirty(dn
, tx
);
1689 if (trunc
&& dn
->dn_maxblkid
>= (off
>> blkshift
))
1690 dn
->dn_maxblkid
= (off
>> blkshift
? (off
>> blkshift
) - 1 : 0);
1692 rw_exit(&dn
->dn_struct_rwlock
);
1696 dnode_spill_freed(dnode_t
*dn
)
1700 mutex_enter(&dn
->dn_mtx
);
1701 for (i
= 0; i
< TXG_SIZE
; i
++) {
1702 if (dn
->dn_rm_spillblk
[i
] == DN_KILL_SPILLBLK
)
1705 mutex_exit(&dn
->dn_mtx
);
1706 return (i
< TXG_SIZE
);
1709 /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */
1711 dnode_block_freed(dnode_t
*dn
, uint64_t blkid
)
1713 free_range_t range_tofind
;
1714 void *dp
= spa_get_dsl(dn
->dn_objset
->os_spa
);
1717 if (blkid
== DMU_BONUS_BLKID
)
1721 * If we're in the process of opening the pool, dp will not be
1722 * set yet, but there shouldn't be anything dirty.
1727 if (dn
->dn_free_txg
)
1730 if (blkid
== DMU_SPILL_BLKID
)
1731 return (dnode_spill_freed(dn
));
1733 range_tofind
.fr_blkid
= blkid
;
1734 mutex_enter(&dn
->dn_mtx
);
1735 for (i
= 0; i
< TXG_SIZE
; i
++) {
1736 free_range_t
*range_found
;
1739 range_found
= avl_find(&dn
->dn_ranges
[i
], &range_tofind
, &idx
);
1741 ASSERT(range_found
->fr_nblks
> 0);
1744 range_found
= avl_nearest(&dn
->dn_ranges
[i
], idx
, AVL_BEFORE
);
1746 range_found
->fr_blkid
+ range_found
->fr_nblks
> blkid
)
1749 mutex_exit(&dn
->dn_mtx
);
1750 return (i
< TXG_SIZE
);
1753 /* call from syncing context when we actually write/free space for this dnode */
1755 dnode_diduse_space(dnode_t
*dn
, int64_t delta
)
1758 dprintf_dnode(dn
, "dn=%p dnp=%p used=%llu delta=%lld\n",
1760 (u_longlong_t
)dn
->dn_phys
->dn_used
,
1763 mutex_enter(&dn
->dn_mtx
);
1764 space
= DN_USED_BYTES(dn
->dn_phys
);
1766 ASSERT3U(space
+ delta
, >=, space
); /* no overflow */
1768 ASSERT3U(space
, >=, -delta
); /* no underflow */
1771 if (spa_version(dn
->dn_objset
->os_spa
) < SPA_VERSION_DNODE_BYTES
) {
1772 ASSERT((dn
->dn_phys
->dn_flags
& DNODE_FLAG_USED_BYTES
) == 0);
1773 ASSERT3U(P2PHASE(space
, 1<<DEV_BSHIFT
), ==, 0);
1774 dn
->dn_phys
->dn_used
= space
>> DEV_BSHIFT
;
1776 dn
->dn_phys
->dn_used
= space
;
1777 dn
->dn_phys
->dn_flags
|= DNODE_FLAG_USED_BYTES
;
1779 mutex_exit(&dn
->dn_mtx
);
1783 * Call when we think we're going to write/free space in open context.
1784 * Be conservative (ie. OK to write less than this or free more than
1785 * this, but don't write more or free less).
1788 dnode_willuse_space(dnode_t
*dn
, int64_t space
, dmu_tx_t
*tx
)
1790 objset_t
*os
= dn
->dn_objset
;
1791 dsl_dataset_t
*ds
= os
->os_dsl_dataset
;
1794 space
= spa_get_asize(os
->os_spa
, space
);
1797 dsl_dir_willuse_space(ds
->ds_dir
, space
, tx
);
1799 dmu_tx_willuse_space(tx
, space
);
1803 * This function scans a block at the indicated "level" looking for
1804 * a hole or data (depending on 'flags'). If level > 0, then we are
1805 * scanning an indirect block looking at its pointers. If level == 0,
1806 * then we are looking at a block of dnodes. If we don't find what we
1807 * are looking for in the block, we return ESRCH. Otherwise, return
1808 * with *offset pointing to the beginning (if searching forwards) or
1809 * end (if searching backwards) of the range covered by the block
1810 * pointer we matched on (or dnode).
1812 * The basic search algorithm used below by dnode_next_offset() is to
1813 * use this function to search up the block tree (widen the search) until
1814 * we find something (i.e., we don't return ESRCH) and then search back
1815 * down the tree (narrow the search) until we reach our original search
1819 dnode_next_offset_level(dnode_t
*dn
, int flags
, uint64_t *offset
,
1820 int lvl
, uint64_t blkfill
, uint64_t txg
)
1822 dmu_buf_impl_t
*db
= NULL
;
1824 uint64_t epbs
= dn
->dn_phys
->dn_indblkshift
- SPA_BLKPTRSHIFT
;
1825 uint64_t epb
= 1ULL << epbs
;
1826 uint64_t minfill
, maxfill
;
1828 int i
, inc
, error
, span
;
1830 dprintf("probing object %llu offset %llx level %d of %u\n",
1831 dn
->dn_object
, *offset
, lvl
, dn
->dn_phys
->dn_nlevels
);
1833 hole
= ((flags
& DNODE_FIND_HOLE
) != 0);
1834 inc
= (flags
& DNODE_FIND_BACKWARDS
) ? -1 : 1;
1835 ASSERT(txg
== 0 || !hole
);
1837 if (lvl
== dn
->dn_phys
->dn_nlevels
) {
1839 epb
= dn
->dn_phys
->dn_nblkptr
;
1840 data
= dn
->dn_phys
->dn_blkptr
;
1842 uint64_t blkid
= dbuf_whichblock(dn
, *offset
) >> (epbs
* lvl
);
1843 error
= dbuf_hold_impl(dn
, lvl
, blkid
, TRUE
, FTAG
, &db
);
1845 if (error
!= ENOENT
)
1850 * This can only happen when we are searching up
1851 * the block tree for data. We don't really need to
1852 * adjust the offset, as we will just end up looking
1853 * at the pointer to this block in its parent, and its
1854 * going to be unallocated, so we will skip over it.
1858 error
= dbuf_read(db
, NULL
, DB_RF_CANFAIL
| DB_RF_HAVESTRUCT
);
1860 dbuf_rele(db
, FTAG
);
1863 data
= db
->db
.db_data
;
1867 (db
->db_blkptr
== NULL
|| db
->db_blkptr
->blk_birth
<= txg
)) {
1869 * This can only happen when we are searching up the tree
1870 * and these conditions mean that we need to keep climbing.
1873 } else if (lvl
== 0) {
1874 dnode_phys_t
*dnp
= data
;
1876 ASSERT(dn
->dn_type
== DMU_OT_DNODE
);
1878 for (i
= (*offset
>> span
) & (blkfill
- 1);
1879 i
>= 0 && i
< blkfill
; i
+= inc
) {
1880 if ((dnp
[i
].dn_type
== DMU_OT_NONE
) == hole
)
1882 *offset
+= (1ULL << span
) * inc
;
1884 if (i
< 0 || i
== blkfill
)
1887 blkptr_t
*bp
= data
;
1888 uint64_t start
= *offset
;
1889 span
= (lvl
- 1) * epbs
+ dn
->dn_datablkshift
;
1891 maxfill
= blkfill
<< ((lvl
- 1) * epbs
);
1898 *offset
= *offset
>> span
;
1899 for (i
= BF64_GET(*offset
, 0, epbs
);
1900 i
>= 0 && i
< epb
; i
+= inc
) {
1901 if (bp
[i
].blk_fill
>= minfill
&&
1902 bp
[i
].blk_fill
<= maxfill
&&
1903 (hole
|| bp
[i
].blk_birth
> txg
))
1905 if (inc
> 0 || *offset
> 0)
1908 *offset
= *offset
<< span
;
1910 /* traversing backwards; position offset at the end */
1911 ASSERT3U(*offset
, <=, start
);
1912 *offset
= MIN(*offset
+ (1ULL << span
) - 1, start
);
1913 } else if (*offset
< start
) {
1916 if (i
< 0 || i
>= epb
)
1921 dbuf_rele(db
, FTAG
);
1927 * Find the next hole, data, or sparse region at or after *offset.
1928 * The value 'blkfill' tells us how many items we expect to find
1929 * in an L0 data block; this value is 1 for normal objects,
1930 * DNODES_PER_BLOCK for the meta dnode, and some fraction of
1931 * DNODES_PER_BLOCK when searching for sparse regions thereof.
1935 * dnode_next_offset(dn, flags, offset, 1, 1, 0);
1936 * Finds the next/previous hole/data in a file.
1937 * Used in dmu_offset_next().
1939 * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg);
1940 * Finds the next free/allocated dnode an objset's meta-dnode.
1941 * Only finds objects that have new contents since txg (ie.
1942 * bonus buffer changes and content removal are ignored).
1943 * Used in dmu_object_next().
1945 * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0);
1946 * Finds the next L2 meta-dnode bp that's at most 1/4 full.
1947 * Used in dmu_object_alloc().
1950 dnode_next_offset(dnode_t
*dn
, int flags
, uint64_t *offset
,
1951 int minlvl
, uint64_t blkfill
, uint64_t txg
)
1953 uint64_t initial_offset
= *offset
;
1957 if (!(flags
& DNODE_FIND_HAVELOCK
))
1958 rw_enter(&dn
->dn_struct_rwlock
, RW_READER
);
1960 if (dn
->dn_phys
->dn_nlevels
== 0) {
1965 if (dn
->dn_datablkshift
== 0) {
1966 if (*offset
< dn
->dn_datablksz
) {
1967 if (flags
& DNODE_FIND_HOLE
)
1968 *offset
= dn
->dn_datablksz
;
1975 maxlvl
= dn
->dn_phys
->dn_nlevels
;
1977 for (lvl
= minlvl
; lvl
<= maxlvl
; lvl
++) {
1978 error
= dnode_next_offset_level(dn
,
1979 flags
, offset
, lvl
, blkfill
, txg
);
1984 while (error
== 0 && --lvl
>= minlvl
) {
1985 error
= dnode_next_offset_level(dn
,
1986 flags
, offset
, lvl
, blkfill
, txg
);
1989 if (error
== 0 && (flags
& DNODE_FIND_BACKWARDS
?
1990 initial_offset
< *offset
: initial_offset
> *offset
))
1993 if (!(flags
& DNODE_FIND_HAVELOCK
))
1994 rw_exit(&dn
->dn_struct_rwlock
);