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, 2017 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>
40 #include <sys/trace_dnode.h>
41 #include <sys/zfs_project.h>
43 dnode_stats_t dnode_stats
= {
44 { "dnode_hold_dbuf_hold", KSTAT_DATA_UINT64
},
45 { "dnode_hold_dbuf_read", KSTAT_DATA_UINT64
},
46 { "dnode_hold_alloc_hits", KSTAT_DATA_UINT64
},
47 { "dnode_hold_alloc_misses", KSTAT_DATA_UINT64
},
48 { "dnode_hold_alloc_interior", KSTAT_DATA_UINT64
},
49 { "dnode_hold_alloc_lock_retry", KSTAT_DATA_UINT64
},
50 { "dnode_hold_alloc_lock_misses", KSTAT_DATA_UINT64
},
51 { "dnode_hold_alloc_type_none", KSTAT_DATA_UINT64
},
52 { "dnode_hold_free_hits", KSTAT_DATA_UINT64
},
53 { "dnode_hold_free_misses", KSTAT_DATA_UINT64
},
54 { "dnode_hold_free_lock_misses", KSTAT_DATA_UINT64
},
55 { "dnode_hold_free_lock_retry", KSTAT_DATA_UINT64
},
56 { "dnode_hold_free_overflow", KSTAT_DATA_UINT64
},
57 { "dnode_hold_free_refcount", KSTAT_DATA_UINT64
},
58 { "dnode_hold_free_txg", KSTAT_DATA_UINT64
},
59 { "dnode_free_interior_lock_retry", KSTAT_DATA_UINT64
},
60 { "dnode_allocate", KSTAT_DATA_UINT64
},
61 { "dnode_reallocate", KSTAT_DATA_UINT64
},
62 { "dnode_buf_evict", KSTAT_DATA_UINT64
},
63 { "dnode_alloc_next_chunk", KSTAT_DATA_UINT64
},
64 { "dnode_alloc_race", KSTAT_DATA_UINT64
},
65 { "dnode_alloc_next_block", KSTAT_DATA_UINT64
},
66 { "dnode_move_invalid", KSTAT_DATA_UINT64
},
67 { "dnode_move_recheck1", KSTAT_DATA_UINT64
},
68 { "dnode_move_recheck2", KSTAT_DATA_UINT64
},
69 { "dnode_move_special", KSTAT_DATA_UINT64
},
70 { "dnode_move_handle", KSTAT_DATA_UINT64
},
71 { "dnode_move_rwlock", KSTAT_DATA_UINT64
},
72 { "dnode_move_active", KSTAT_DATA_UINT64
},
75 static kstat_t
*dnode_ksp
;
76 static kmem_cache_t
*dnode_cache
;
78 ASSERTV(static dnode_phys_t dnode_phys_zero
);
80 int zfs_default_bs
= SPA_MINBLOCKSHIFT
;
81 int zfs_default_ibs
= DN_MAX_INDBLKSHIFT
;
84 static kmem_cbrc_t
dnode_move(void *, void *, size_t, void *);
88 dbuf_compare(const void *x1
, const void *x2
)
90 const dmu_buf_impl_t
*d1
= x1
;
91 const dmu_buf_impl_t
*d2
= x2
;
93 int cmp
= AVL_CMP(d1
->db_level
, d2
->db_level
);
97 cmp
= AVL_CMP(d1
->db_blkid
, d2
->db_blkid
);
101 if (d1
->db_state
== DB_SEARCH
) {
102 ASSERT3S(d2
->db_state
, !=, DB_SEARCH
);
104 } else if (d2
->db_state
== DB_SEARCH
) {
105 ASSERT3S(d1
->db_state
, !=, DB_SEARCH
);
109 return (AVL_PCMP(d1
, d2
));
114 dnode_cons(void *arg
, void *unused
, int kmflag
)
119 rw_init(&dn
->dn_struct_rwlock
, NULL
, RW_NOLOCKDEP
, NULL
);
120 mutex_init(&dn
->dn_mtx
, NULL
, MUTEX_DEFAULT
, NULL
);
121 mutex_init(&dn
->dn_dbufs_mtx
, NULL
, MUTEX_DEFAULT
, NULL
);
122 cv_init(&dn
->dn_notxholds
, NULL
, CV_DEFAULT
, NULL
);
125 * Every dbuf has a reference, and dropping a tracked reference is
126 * O(number of references), so don't track dn_holds.
128 zfs_refcount_create_untracked(&dn
->dn_holds
);
129 zfs_refcount_create(&dn
->dn_tx_holds
);
130 list_link_init(&dn
->dn_link
);
132 bzero(&dn
->dn_next_nblkptr
[0], sizeof (dn
->dn_next_nblkptr
));
133 bzero(&dn
->dn_next_nlevels
[0], sizeof (dn
->dn_next_nlevels
));
134 bzero(&dn
->dn_next_indblkshift
[0], sizeof (dn
->dn_next_indblkshift
));
135 bzero(&dn
->dn_next_bonustype
[0], sizeof (dn
->dn_next_bonustype
));
136 bzero(&dn
->dn_rm_spillblk
[0], sizeof (dn
->dn_rm_spillblk
));
137 bzero(&dn
->dn_next_bonuslen
[0], sizeof (dn
->dn_next_bonuslen
));
138 bzero(&dn
->dn_next_blksz
[0], sizeof (dn
->dn_next_blksz
));
139 bzero(&dn
->dn_next_maxblkid
[0], sizeof (dn
->dn_next_maxblkid
));
141 for (i
= 0; i
< TXG_SIZE
; i
++) {
142 multilist_link_init(&dn
->dn_dirty_link
[i
]);
143 dn
->dn_free_ranges
[i
] = NULL
;
144 list_create(&dn
->dn_dirty_records
[i
],
145 sizeof (dbuf_dirty_record_t
),
146 offsetof(dbuf_dirty_record_t
, dr_dirty_node
));
149 dn
->dn_allocated_txg
= 0;
151 dn
->dn_assigned_txg
= 0;
152 dn
->dn_dirty_txg
= 0;
154 dn
->dn_dirtyctx_firstset
= NULL
;
156 dn
->dn_have_spill
= B_FALSE
;
162 dn
->dn_oldprojid
= ZFS_DEFAULT_PROJID
;
165 dn
->dn_newprojid
= ZFS_DEFAULT_PROJID
;
168 dn
->dn_dbufs_count
= 0;
169 avl_create(&dn
->dn_dbufs
, dbuf_compare
, sizeof (dmu_buf_impl_t
),
170 offsetof(dmu_buf_impl_t
, db_link
));
178 dnode_dest(void *arg
, void *unused
)
183 rw_destroy(&dn
->dn_struct_rwlock
);
184 mutex_destroy(&dn
->dn_mtx
);
185 mutex_destroy(&dn
->dn_dbufs_mtx
);
186 cv_destroy(&dn
->dn_notxholds
);
187 zfs_refcount_destroy(&dn
->dn_holds
);
188 zfs_refcount_destroy(&dn
->dn_tx_holds
);
189 ASSERT(!list_link_active(&dn
->dn_link
));
191 for (i
= 0; i
< TXG_SIZE
; i
++) {
192 ASSERT(!multilist_link_active(&dn
->dn_dirty_link
[i
]));
193 ASSERT3P(dn
->dn_free_ranges
[i
], ==, NULL
);
194 list_destroy(&dn
->dn_dirty_records
[i
]);
195 ASSERT0(dn
->dn_next_nblkptr
[i
]);
196 ASSERT0(dn
->dn_next_nlevels
[i
]);
197 ASSERT0(dn
->dn_next_indblkshift
[i
]);
198 ASSERT0(dn
->dn_next_bonustype
[i
]);
199 ASSERT0(dn
->dn_rm_spillblk
[i
]);
200 ASSERT0(dn
->dn_next_bonuslen
[i
]);
201 ASSERT0(dn
->dn_next_blksz
[i
]);
202 ASSERT0(dn
->dn_next_maxblkid
[i
]);
205 ASSERT0(dn
->dn_allocated_txg
);
206 ASSERT0(dn
->dn_free_txg
);
207 ASSERT0(dn
->dn_assigned_txg
);
208 ASSERT0(dn
->dn_dirty_txg
);
209 ASSERT0(dn
->dn_dirtyctx
);
210 ASSERT3P(dn
->dn_dirtyctx_firstset
, ==, NULL
);
211 ASSERT3P(dn
->dn_bonus
, ==, NULL
);
212 ASSERT(!dn
->dn_have_spill
);
213 ASSERT3P(dn
->dn_zio
, ==, NULL
);
214 ASSERT0(dn
->dn_oldused
);
215 ASSERT0(dn
->dn_oldflags
);
216 ASSERT0(dn
->dn_olduid
);
217 ASSERT0(dn
->dn_oldgid
);
218 ASSERT0(dn
->dn_oldprojid
);
219 ASSERT0(dn
->dn_newuid
);
220 ASSERT0(dn
->dn_newgid
);
221 ASSERT0(dn
->dn_newprojid
);
222 ASSERT0(dn
->dn_id_flags
);
224 ASSERT0(dn
->dn_dbufs_count
);
225 avl_destroy(&dn
->dn_dbufs
);
231 ASSERT(dnode_cache
== NULL
);
232 dnode_cache
= kmem_cache_create("dnode_t", sizeof (dnode_t
),
233 0, dnode_cons
, dnode_dest
, NULL
, NULL
, NULL
, 0);
234 kmem_cache_set_move(dnode_cache
, dnode_move
);
236 dnode_ksp
= kstat_create("zfs", 0, "dnodestats", "misc",
237 KSTAT_TYPE_NAMED
, sizeof (dnode_stats
) / sizeof (kstat_named_t
),
239 if (dnode_ksp
!= NULL
) {
240 dnode_ksp
->ks_data
= &dnode_stats
;
241 kstat_install(dnode_ksp
);
248 if (dnode_ksp
!= NULL
) {
249 kstat_delete(dnode_ksp
);
253 kmem_cache_destroy(dnode_cache
);
260 dnode_verify(dnode_t
*dn
)
262 int drop_struct_lock
= FALSE
;
265 ASSERT(dn
->dn_objset
);
266 ASSERT(dn
->dn_handle
->dnh_dnode
== dn
);
268 ASSERT(DMU_OT_IS_VALID(dn
->dn_phys
->dn_type
));
270 if (!(zfs_flags
& ZFS_DEBUG_DNODE_VERIFY
))
273 if (!RW_WRITE_HELD(&dn
->dn_struct_rwlock
)) {
274 rw_enter(&dn
->dn_struct_rwlock
, RW_READER
);
275 drop_struct_lock
= TRUE
;
277 if (dn
->dn_phys
->dn_type
!= DMU_OT_NONE
|| dn
->dn_allocated_txg
!= 0) {
279 int max_bonuslen
= DN_SLOTS_TO_BONUSLEN(dn
->dn_num_slots
);
280 ASSERT3U(dn
->dn_indblkshift
, <=, SPA_MAXBLOCKSHIFT
);
281 if (dn
->dn_datablkshift
) {
282 ASSERT3U(dn
->dn_datablkshift
, >=, SPA_MINBLOCKSHIFT
);
283 ASSERT3U(dn
->dn_datablkshift
, <=, SPA_MAXBLOCKSHIFT
);
284 ASSERT3U(1<<dn
->dn_datablkshift
, ==, dn
->dn_datablksz
);
286 ASSERT3U(dn
->dn_nlevels
, <=, 30);
287 ASSERT(DMU_OT_IS_VALID(dn
->dn_type
));
288 ASSERT3U(dn
->dn_nblkptr
, >=, 1);
289 ASSERT3U(dn
->dn_nblkptr
, <=, DN_MAX_NBLKPTR
);
290 ASSERT3U(dn
->dn_bonuslen
, <=, max_bonuslen
);
291 ASSERT3U(dn
->dn_datablksz
, ==,
292 dn
->dn_datablkszsec
<< SPA_MINBLOCKSHIFT
);
293 ASSERT3U(ISP2(dn
->dn_datablksz
), ==, dn
->dn_datablkshift
!= 0);
294 ASSERT3U((dn
->dn_nblkptr
- 1) * sizeof (blkptr_t
) +
295 dn
->dn_bonuslen
, <=, max_bonuslen
);
296 for (i
= 0; i
< TXG_SIZE
; i
++) {
297 ASSERT3U(dn
->dn_next_nlevels
[i
], <=, dn
->dn_nlevels
);
300 if (dn
->dn_phys
->dn_type
!= DMU_OT_NONE
)
301 ASSERT3U(dn
->dn_phys
->dn_nlevels
, <=, dn
->dn_nlevels
);
302 ASSERT(DMU_OBJECT_IS_SPECIAL(dn
->dn_object
) || dn
->dn_dbuf
!= NULL
);
303 if (dn
->dn_dbuf
!= NULL
) {
304 ASSERT3P(dn
->dn_phys
, ==,
305 (dnode_phys_t
*)dn
->dn_dbuf
->db
.db_data
+
306 (dn
->dn_object
% (dn
->dn_dbuf
->db
.db_size
>> DNODE_SHIFT
)));
308 if (drop_struct_lock
)
309 rw_exit(&dn
->dn_struct_rwlock
);
314 dnode_byteswap(dnode_phys_t
*dnp
)
316 uint64_t *buf64
= (void*)&dnp
->dn_blkptr
;
319 if (dnp
->dn_type
== DMU_OT_NONE
) {
320 bzero(dnp
, sizeof (dnode_phys_t
));
324 dnp
->dn_datablkszsec
= BSWAP_16(dnp
->dn_datablkszsec
);
325 dnp
->dn_bonuslen
= BSWAP_16(dnp
->dn_bonuslen
);
326 dnp
->dn_extra_slots
= BSWAP_8(dnp
->dn_extra_slots
);
327 dnp
->dn_maxblkid
= BSWAP_64(dnp
->dn_maxblkid
);
328 dnp
->dn_used
= BSWAP_64(dnp
->dn_used
);
331 * dn_nblkptr is only one byte, so it's OK to read it in either
332 * byte order. We can't read dn_bouslen.
334 ASSERT(dnp
->dn_indblkshift
<= SPA_MAXBLOCKSHIFT
);
335 ASSERT(dnp
->dn_nblkptr
<= DN_MAX_NBLKPTR
);
336 for (i
= 0; i
< dnp
->dn_nblkptr
* sizeof (blkptr_t
)/8; i
++)
337 buf64
[i
] = BSWAP_64(buf64
[i
]);
340 * OK to check dn_bonuslen for zero, because it won't matter if
341 * we have the wrong byte order. This is necessary because the
342 * dnode dnode is smaller than a regular dnode.
344 if (dnp
->dn_bonuslen
!= 0) {
346 * Note that the bonus length calculated here may be
347 * longer than the actual bonus buffer. This is because
348 * we always put the bonus buffer after the last block
349 * pointer (instead of packing it against the end of the
352 int off
= (dnp
->dn_nblkptr
-1) * sizeof (blkptr_t
);
353 int slots
= dnp
->dn_extra_slots
+ 1;
354 size_t len
= DN_SLOTS_TO_BONUSLEN(slots
) - off
;
355 dmu_object_byteswap_t byteswap
;
356 ASSERT(DMU_OT_IS_VALID(dnp
->dn_bonustype
));
357 byteswap
= DMU_OT_BYTESWAP(dnp
->dn_bonustype
);
358 dmu_ot_byteswap
[byteswap
].ob_func(dnp
->dn_bonus
+ off
, len
);
361 /* Swap SPILL block if we have one */
362 if (dnp
->dn_flags
& DNODE_FLAG_SPILL_BLKPTR
)
363 byteswap_uint64_array(DN_SPILL_BLKPTR(dnp
), sizeof (blkptr_t
));
367 dnode_buf_byteswap(void *vbuf
, size_t size
)
371 ASSERT3U(sizeof (dnode_phys_t
), ==, (1<<DNODE_SHIFT
));
372 ASSERT((size
& (sizeof (dnode_phys_t
)-1)) == 0);
375 dnode_phys_t
*dnp
= (void *)(((char *)vbuf
) + i
);
379 if (dnp
->dn_type
!= DMU_OT_NONE
)
380 i
+= dnp
->dn_extra_slots
* DNODE_MIN_SIZE
;
385 dnode_setbonuslen(dnode_t
*dn
, int newsize
, dmu_tx_t
*tx
)
387 ASSERT3U(zfs_refcount_count(&dn
->dn_holds
), >=, 1);
389 dnode_setdirty(dn
, tx
);
390 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
391 ASSERT3U(newsize
, <=, DN_SLOTS_TO_BONUSLEN(dn
->dn_num_slots
) -
392 (dn
->dn_nblkptr
-1) * sizeof (blkptr_t
));
393 dn
->dn_bonuslen
= newsize
;
395 dn
->dn_next_bonuslen
[tx
->tx_txg
& TXG_MASK
] = DN_ZERO_BONUSLEN
;
397 dn
->dn_next_bonuslen
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_bonuslen
;
398 rw_exit(&dn
->dn_struct_rwlock
);
402 dnode_setbonus_type(dnode_t
*dn
, dmu_object_type_t newtype
, dmu_tx_t
*tx
)
404 ASSERT3U(zfs_refcount_count(&dn
->dn_holds
), >=, 1);
405 dnode_setdirty(dn
, tx
);
406 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
407 dn
->dn_bonustype
= newtype
;
408 dn
->dn_next_bonustype
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_bonustype
;
409 rw_exit(&dn
->dn_struct_rwlock
);
413 dnode_rm_spill(dnode_t
*dn
, dmu_tx_t
*tx
)
415 ASSERT3U(zfs_refcount_count(&dn
->dn_holds
), >=, 1);
416 ASSERT(RW_WRITE_HELD(&dn
->dn_struct_rwlock
));
417 dnode_setdirty(dn
, tx
);
418 dn
->dn_rm_spillblk
[tx
->tx_txg
&TXG_MASK
] = DN_KILL_SPILLBLK
;
419 dn
->dn_have_spill
= B_FALSE
;
423 dnode_setdblksz(dnode_t
*dn
, int size
)
425 ASSERT0(P2PHASE(size
, SPA_MINBLOCKSIZE
));
426 ASSERT3U(size
, <=, SPA_MAXBLOCKSIZE
);
427 ASSERT3U(size
, >=, SPA_MINBLOCKSIZE
);
428 ASSERT3U(size
>> SPA_MINBLOCKSHIFT
, <,
429 1<<(sizeof (dn
->dn_phys
->dn_datablkszsec
) * 8));
430 dn
->dn_datablksz
= size
;
431 dn
->dn_datablkszsec
= size
>> SPA_MINBLOCKSHIFT
;
432 dn
->dn_datablkshift
= ISP2(size
) ? highbit64(size
- 1) : 0;
436 dnode_create(objset_t
*os
, dnode_phys_t
*dnp
, dmu_buf_impl_t
*db
,
437 uint64_t object
, dnode_handle_t
*dnh
)
441 dn
= kmem_cache_alloc(dnode_cache
, KM_SLEEP
);
442 ASSERT(!POINTER_IS_VALID(dn
->dn_objset
));
446 * Defer setting dn_objset until the dnode is ready to be a candidate
447 * for the dnode_move() callback.
449 dn
->dn_object
= object
;
454 if (dnp
->dn_datablkszsec
) {
455 dnode_setdblksz(dn
, dnp
->dn_datablkszsec
<< SPA_MINBLOCKSHIFT
);
457 dn
->dn_datablksz
= 0;
458 dn
->dn_datablkszsec
= 0;
459 dn
->dn_datablkshift
= 0;
461 dn
->dn_indblkshift
= dnp
->dn_indblkshift
;
462 dn
->dn_nlevels
= dnp
->dn_nlevels
;
463 dn
->dn_type
= dnp
->dn_type
;
464 dn
->dn_nblkptr
= dnp
->dn_nblkptr
;
465 dn
->dn_checksum
= dnp
->dn_checksum
;
466 dn
->dn_compress
= dnp
->dn_compress
;
467 dn
->dn_bonustype
= dnp
->dn_bonustype
;
468 dn
->dn_bonuslen
= dnp
->dn_bonuslen
;
469 dn
->dn_num_slots
= dnp
->dn_extra_slots
+ 1;
470 dn
->dn_maxblkid
= dnp
->dn_maxblkid
;
471 dn
->dn_have_spill
= ((dnp
->dn_flags
& DNODE_FLAG_SPILL_BLKPTR
) != 0);
474 dmu_zfetch_init(&dn
->dn_zfetch
, dn
);
476 ASSERT(DMU_OT_IS_VALID(dn
->dn_phys
->dn_type
));
477 ASSERT(zrl_is_locked(&dnh
->dnh_zrlock
));
478 ASSERT(!DN_SLOT_IS_PTR(dnh
->dnh_dnode
));
480 mutex_enter(&os
->os_lock
);
483 * Exclude special dnodes from os_dnodes so an empty os_dnodes
484 * signifies that the special dnodes have no references from
485 * their children (the entries in os_dnodes). This allows
486 * dnode_destroy() to easily determine if the last child has
487 * been removed and then complete eviction of the objset.
489 if (!DMU_OBJECT_IS_SPECIAL(object
))
490 list_insert_head(&os
->os_dnodes
, dn
);
494 * Everything else must be valid before assigning dn_objset
495 * makes the dnode eligible for dnode_move().
500 mutex_exit(&os
->os_lock
);
502 arc_space_consume(sizeof (dnode_t
), ARC_SPACE_DNODE
);
508 * Caller must be holding the dnode handle, which is released upon return.
511 dnode_destroy(dnode_t
*dn
)
513 objset_t
*os
= dn
->dn_objset
;
514 boolean_t complete_os_eviction
= B_FALSE
;
516 ASSERT((dn
->dn_id_flags
& DN_ID_NEW_EXIST
) == 0);
518 mutex_enter(&os
->os_lock
);
519 POINTER_INVALIDATE(&dn
->dn_objset
);
520 if (!DMU_OBJECT_IS_SPECIAL(dn
->dn_object
)) {
521 list_remove(&os
->os_dnodes
, dn
);
522 complete_os_eviction
=
523 list_is_empty(&os
->os_dnodes
) &&
524 list_link_active(&os
->os_evicting_node
);
526 mutex_exit(&os
->os_lock
);
528 /* the dnode can no longer move, so we can release the handle */
529 if (!zrl_is_locked(&dn
->dn_handle
->dnh_zrlock
))
530 zrl_remove(&dn
->dn_handle
->dnh_zrlock
);
532 dn
->dn_allocated_txg
= 0;
534 dn
->dn_assigned_txg
= 0;
535 dn
->dn_dirty_txg
= 0;
538 if (dn
->dn_dirtyctx_firstset
!= NULL
) {
539 kmem_free(dn
->dn_dirtyctx_firstset
, 1);
540 dn
->dn_dirtyctx_firstset
= NULL
;
542 if (dn
->dn_bonus
!= NULL
) {
543 mutex_enter(&dn
->dn_bonus
->db_mtx
);
544 dbuf_destroy(dn
->dn_bonus
);
549 dn
->dn_have_spill
= B_FALSE
;
554 dn
->dn_oldprojid
= ZFS_DEFAULT_PROJID
;
557 dn
->dn_newprojid
= ZFS_DEFAULT_PROJID
;
560 dmu_zfetch_fini(&dn
->dn_zfetch
);
561 kmem_cache_free(dnode_cache
, dn
);
562 arc_space_return(sizeof (dnode_t
), ARC_SPACE_DNODE
);
564 if (complete_os_eviction
)
565 dmu_objset_evict_done(os
);
569 dnode_allocate(dnode_t
*dn
, dmu_object_type_t ot
, int blocksize
, int ibs
,
570 dmu_object_type_t bonustype
, int bonuslen
, int dn_slots
, dmu_tx_t
*tx
)
574 ASSERT3U(dn_slots
, >, 0);
575 ASSERT3U(dn_slots
<< DNODE_SHIFT
, <=,
576 spa_maxdnodesize(dmu_objset_spa(dn
->dn_objset
)));
577 ASSERT3U(blocksize
, <=,
578 spa_maxblocksize(dmu_objset_spa(dn
->dn_objset
)));
580 blocksize
= 1 << zfs_default_bs
;
582 blocksize
= P2ROUNDUP(blocksize
, SPA_MINBLOCKSIZE
);
585 ibs
= zfs_default_ibs
;
587 ibs
= MIN(MAX(ibs
, DN_MIN_INDBLKSHIFT
), DN_MAX_INDBLKSHIFT
);
589 dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d dn_slots=%d\n",
590 dn
->dn_objset
, dn
->dn_object
, tx
->tx_txg
, blocksize
, ibs
, dn_slots
);
591 DNODE_STAT_BUMP(dnode_allocate
);
593 ASSERT(dn
->dn_type
== DMU_OT_NONE
);
594 ASSERT(bcmp(dn
->dn_phys
, &dnode_phys_zero
, sizeof (dnode_phys_t
)) == 0);
595 ASSERT(dn
->dn_phys
->dn_type
== DMU_OT_NONE
);
596 ASSERT(ot
!= DMU_OT_NONE
);
597 ASSERT(DMU_OT_IS_VALID(ot
));
598 ASSERT((bonustype
== DMU_OT_NONE
&& bonuslen
== 0) ||
599 (bonustype
== DMU_OT_SA
&& bonuslen
== 0) ||
600 (bonustype
!= DMU_OT_NONE
&& bonuslen
!= 0));
601 ASSERT(DMU_OT_IS_VALID(bonustype
));
602 ASSERT3U(bonuslen
, <=, DN_SLOTS_TO_BONUSLEN(dn_slots
));
603 ASSERT(dn
->dn_type
== DMU_OT_NONE
);
604 ASSERT0(dn
->dn_maxblkid
);
605 ASSERT0(dn
->dn_allocated_txg
);
606 ASSERT0(dn
->dn_assigned_txg
);
607 ASSERT0(dn
->dn_dirty_txg
);
608 ASSERT(zfs_refcount_is_zero(&dn
->dn_tx_holds
));
609 ASSERT3U(zfs_refcount_count(&dn
->dn_holds
), <=, 1);
610 ASSERT(avl_is_empty(&dn
->dn_dbufs
));
612 for (i
= 0; i
< TXG_SIZE
; i
++) {
613 ASSERT0(dn
->dn_next_nblkptr
[i
]);
614 ASSERT0(dn
->dn_next_nlevels
[i
]);
615 ASSERT0(dn
->dn_next_indblkshift
[i
]);
616 ASSERT0(dn
->dn_next_bonuslen
[i
]);
617 ASSERT0(dn
->dn_next_bonustype
[i
]);
618 ASSERT0(dn
->dn_rm_spillblk
[i
]);
619 ASSERT0(dn
->dn_next_blksz
[i
]);
620 ASSERT0(dn
->dn_next_maxblkid
[i
]);
621 ASSERT(!multilist_link_active(&dn
->dn_dirty_link
[i
]));
622 ASSERT3P(list_head(&dn
->dn_dirty_records
[i
]), ==, NULL
);
623 ASSERT3P(dn
->dn_free_ranges
[i
], ==, NULL
);
627 dnode_setdblksz(dn
, blocksize
);
628 dn
->dn_indblkshift
= ibs
;
630 dn
->dn_num_slots
= dn_slots
;
631 if (bonustype
== DMU_OT_SA
) /* Maximize bonus space for SA */
634 dn
->dn_nblkptr
= MIN(DN_MAX_NBLKPTR
,
635 1 + ((DN_SLOTS_TO_BONUSLEN(dn_slots
) - bonuslen
) >>
639 dn
->dn_bonustype
= bonustype
;
640 dn
->dn_bonuslen
= bonuslen
;
641 dn
->dn_checksum
= ZIO_CHECKSUM_INHERIT
;
642 dn
->dn_compress
= ZIO_COMPRESS_INHERIT
;
646 if (dn
->dn_dirtyctx_firstset
) {
647 kmem_free(dn
->dn_dirtyctx_firstset
, 1);
648 dn
->dn_dirtyctx_firstset
= NULL
;
651 dn
->dn_allocated_txg
= tx
->tx_txg
;
654 dnode_setdirty(dn
, tx
);
655 dn
->dn_next_indblkshift
[tx
->tx_txg
& TXG_MASK
] = ibs
;
656 dn
->dn_next_bonuslen
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_bonuslen
;
657 dn
->dn_next_bonustype
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_bonustype
;
658 dn
->dn_next_blksz
[tx
->tx_txg
& TXG_MASK
] = dn
->dn_datablksz
;
662 dnode_reallocate(dnode_t
*dn
, dmu_object_type_t ot
, int blocksize
,
663 dmu_object_type_t bonustype
, int bonuslen
, int dn_slots
, dmu_tx_t
*tx
)
667 ASSERT3U(blocksize
, >=, SPA_MINBLOCKSIZE
);
668 ASSERT3U(blocksize
, <=,
669 spa_maxblocksize(dmu_objset_spa(dn
->dn_objset
)));
670 ASSERT0(blocksize
% SPA_MINBLOCKSIZE
);
671 ASSERT(dn
->dn_object
!= DMU_META_DNODE_OBJECT
|| dmu_tx_private_ok(tx
));
672 ASSERT(tx
->tx_txg
!= 0);
673 ASSERT((bonustype
== DMU_OT_NONE
&& bonuslen
== 0) ||
674 (bonustype
!= DMU_OT_NONE
&& bonuslen
!= 0) ||
675 (bonustype
== DMU_OT_SA
&& bonuslen
== 0));
676 ASSERT(DMU_OT_IS_VALID(bonustype
));
677 ASSERT3U(bonuslen
, <=,
678 DN_BONUS_SIZE(spa_maxdnodesize(dmu_objset_spa(dn
->dn_objset
))));
679 ASSERT3U(bonuslen
, <=, DN_BONUS_SIZE(dn_slots
<< DNODE_SHIFT
));
681 dnode_free_interior_slots(dn
);
682 DNODE_STAT_BUMP(dnode_reallocate
);
684 /* clean up any unreferenced dbufs */
685 dnode_evict_dbufs(dn
);
689 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
690 dnode_setdirty(dn
, tx
);
691 if (dn
->dn_datablksz
!= blocksize
) {
692 /* change blocksize */
693 ASSERT(dn
->dn_maxblkid
== 0 &&
694 (BP_IS_HOLE(&dn
->dn_phys
->dn_blkptr
[0]) ||
695 dnode_block_freed(dn
, 0)));
696 dnode_setdblksz(dn
, blocksize
);
697 dn
->dn_next_blksz
[tx
->tx_txg
&TXG_MASK
] = blocksize
;
699 if (dn
->dn_bonuslen
!= bonuslen
)
700 dn
->dn_next_bonuslen
[tx
->tx_txg
&TXG_MASK
] = bonuslen
;
702 if (bonustype
== DMU_OT_SA
) /* Maximize bonus space for SA */
705 nblkptr
= MIN(DN_MAX_NBLKPTR
,
706 1 + ((DN_SLOTS_TO_BONUSLEN(dn_slots
) - bonuslen
) >>
708 if (dn
->dn_bonustype
!= bonustype
)
709 dn
->dn_next_bonustype
[tx
->tx_txg
&TXG_MASK
] = bonustype
;
710 if (dn
->dn_nblkptr
!= nblkptr
)
711 dn
->dn_next_nblkptr
[tx
->tx_txg
&TXG_MASK
] = nblkptr
;
712 if (dn
->dn_phys
->dn_flags
& DNODE_FLAG_SPILL_BLKPTR
) {
713 dbuf_rm_spill(dn
, tx
);
714 dnode_rm_spill(dn
, tx
);
716 rw_exit(&dn
->dn_struct_rwlock
);
721 /* change bonus size and type */
722 mutex_enter(&dn
->dn_mtx
);
723 dn
->dn_bonustype
= bonustype
;
724 dn
->dn_bonuslen
= bonuslen
;
725 dn
->dn_num_slots
= dn_slots
;
726 dn
->dn_nblkptr
= nblkptr
;
727 dn
->dn_checksum
= ZIO_CHECKSUM_INHERIT
;
728 dn
->dn_compress
= ZIO_COMPRESS_INHERIT
;
729 ASSERT3U(dn
->dn_nblkptr
, <=, DN_MAX_NBLKPTR
);
731 /* fix up the bonus db_size */
733 dn
->dn_bonus
->db
.db_size
=
734 DN_SLOTS_TO_BONUSLEN(dn
->dn_num_slots
) -
735 (dn
->dn_nblkptr
-1) * sizeof (blkptr_t
);
736 ASSERT(dn
->dn_bonuslen
<= dn
->dn_bonus
->db
.db_size
);
739 dn
->dn_allocated_txg
= tx
->tx_txg
;
740 mutex_exit(&dn
->dn_mtx
);
745 dnode_move_impl(dnode_t
*odn
, dnode_t
*ndn
)
749 ASSERT(!RW_LOCK_HELD(&odn
->dn_struct_rwlock
));
750 ASSERT(MUTEX_NOT_HELD(&odn
->dn_mtx
));
751 ASSERT(MUTEX_NOT_HELD(&odn
->dn_dbufs_mtx
));
752 ASSERT(!RW_LOCK_HELD(&odn
->dn_zfetch
.zf_rwlock
));
755 ndn
->dn_objset
= odn
->dn_objset
;
756 ndn
->dn_object
= odn
->dn_object
;
757 ndn
->dn_dbuf
= odn
->dn_dbuf
;
758 ndn
->dn_handle
= odn
->dn_handle
;
759 ndn
->dn_phys
= odn
->dn_phys
;
760 ndn
->dn_type
= odn
->dn_type
;
761 ndn
->dn_bonuslen
= odn
->dn_bonuslen
;
762 ndn
->dn_bonustype
= odn
->dn_bonustype
;
763 ndn
->dn_nblkptr
= odn
->dn_nblkptr
;
764 ndn
->dn_checksum
= odn
->dn_checksum
;
765 ndn
->dn_compress
= odn
->dn_compress
;
766 ndn
->dn_nlevels
= odn
->dn_nlevels
;
767 ndn
->dn_indblkshift
= odn
->dn_indblkshift
;
768 ndn
->dn_datablkshift
= odn
->dn_datablkshift
;
769 ndn
->dn_datablkszsec
= odn
->dn_datablkszsec
;
770 ndn
->dn_datablksz
= odn
->dn_datablksz
;
771 ndn
->dn_maxblkid
= odn
->dn_maxblkid
;
772 ndn
->dn_num_slots
= odn
->dn_num_slots
;
773 bcopy(&odn
->dn_next_type
[0], &ndn
->dn_next_type
[0],
774 sizeof (odn
->dn_next_type
));
775 bcopy(&odn
->dn_next_nblkptr
[0], &ndn
->dn_next_nblkptr
[0],
776 sizeof (odn
->dn_next_nblkptr
));
777 bcopy(&odn
->dn_next_nlevels
[0], &ndn
->dn_next_nlevels
[0],
778 sizeof (odn
->dn_next_nlevels
));
779 bcopy(&odn
->dn_next_indblkshift
[0], &ndn
->dn_next_indblkshift
[0],
780 sizeof (odn
->dn_next_indblkshift
));
781 bcopy(&odn
->dn_next_bonustype
[0], &ndn
->dn_next_bonustype
[0],
782 sizeof (odn
->dn_next_bonustype
));
783 bcopy(&odn
->dn_rm_spillblk
[0], &ndn
->dn_rm_spillblk
[0],
784 sizeof (odn
->dn_rm_spillblk
));
785 bcopy(&odn
->dn_next_bonuslen
[0], &ndn
->dn_next_bonuslen
[0],
786 sizeof (odn
->dn_next_bonuslen
));
787 bcopy(&odn
->dn_next_blksz
[0], &ndn
->dn_next_blksz
[0],
788 sizeof (odn
->dn_next_blksz
));
789 bcopy(&odn
->dn_next_maxblkid
[0], &ndn
->dn_next_maxblkid
[0],
790 sizeof (odn
->dn_next_maxblkid
));
791 for (i
= 0; i
< TXG_SIZE
; i
++) {
792 list_move_tail(&ndn
->dn_dirty_records
[i
],
793 &odn
->dn_dirty_records
[i
]);
795 bcopy(&odn
->dn_free_ranges
[0], &ndn
->dn_free_ranges
[0],
796 sizeof (odn
->dn_free_ranges
));
797 ndn
->dn_allocated_txg
= odn
->dn_allocated_txg
;
798 ndn
->dn_free_txg
= odn
->dn_free_txg
;
799 ndn
->dn_assigned_txg
= odn
->dn_assigned_txg
;
800 ndn
->dn_dirty_txg
= odn
->dn_dirty_txg
;
801 ndn
->dn_dirtyctx
= odn
->dn_dirtyctx
;
802 ndn
->dn_dirtyctx_firstset
= odn
->dn_dirtyctx_firstset
;
803 ASSERT(zfs_refcount_count(&odn
->dn_tx_holds
) == 0);
804 zfs_refcount_transfer(&ndn
->dn_holds
, &odn
->dn_holds
);
805 ASSERT(avl_is_empty(&ndn
->dn_dbufs
));
806 avl_swap(&ndn
->dn_dbufs
, &odn
->dn_dbufs
);
807 ndn
->dn_dbufs_count
= odn
->dn_dbufs_count
;
808 ndn
->dn_bonus
= odn
->dn_bonus
;
809 ndn
->dn_have_spill
= odn
->dn_have_spill
;
810 ndn
->dn_zio
= odn
->dn_zio
;
811 ndn
->dn_oldused
= odn
->dn_oldused
;
812 ndn
->dn_oldflags
= odn
->dn_oldflags
;
813 ndn
->dn_olduid
= odn
->dn_olduid
;
814 ndn
->dn_oldgid
= odn
->dn_oldgid
;
815 ndn
->dn_oldprojid
= odn
->dn_oldprojid
;
816 ndn
->dn_newuid
= odn
->dn_newuid
;
817 ndn
->dn_newgid
= odn
->dn_newgid
;
818 ndn
->dn_newprojid
= odn
->dn_newprojid
;
819 ndn
->dn_id_flags
= odn
->dn_id_flags
;
820 dmu_zfetch_init(&ndn
->dn_zfetch
, NULL
);
821 list_move_tail(&ndn
->dn_zfetch
.zf_stream
, &odn
->dn_zfetch
.zf_stream
);
822 ndn
->dn_zfetch
.zf_dnode
= odn
->dn_zfetch
.zf_dnode
;
825 * Update back pointers. Updating the handle fixes the back pointer of
826 * every descendant dbuf as well as the bonus dbuf.
828 ASSERT(ndn
->dn_handle
->dnh_dnode
== odn
);
829 ndn
->dn_handle
->dnh_dnode
= ndn
;
830 if (ndn
->dn_zfetch
.zf_dnode
== odn
) {
831 ndn
->dn_zfetch
.zf_dnode
= ndn
;
835 * Invalidate the original dnode by clearing all of its back pointers.
838 odn
->dn_handle
= NULL
;
839 avl_create(&odn
->dn_dbufs
, dbuf_compare
, sizeof (dmu_buf_impl_t
),
840 offsetof(dmu_buf_impl_t
, db_link
));
841 odn
->dn_dbufs_count
= 0;
842 odn
->dn_bonus
= NULL
;
843 dmu_zfetch_fini(&odn
->dn_zfetch
);
846 * Set the low bit of the objset pointer to ensure that dnode_move()
847 * recognizes the dnode as invalid in any subsequent callback.
849 POINTER_INVALIDATE(&odn
->dn_objset
);
852 * Satisfy the destructor.
854 for (i
= 0; i
< TXG_SIZE
; i
++) {
855 list_create(&odn
->dn_dirty_records
[i
],
856 sizeof (dbuf_dirty_record_t
),
857 offsetof(dbuf_dirty_record_t
, dr_dirty_node
));
858 odn
->dn_free_ranges
[i
] = NULL
;
859 odn
->dn_next_nlevels
[i
] = 0;
860 odn
->dn_next_indblkshift
[i
] = 0;
861 odn
->dn_next_bonustype
[i
] = 0;
862 odn
->dn_rm_spillblk
[i
] = 0;
863 odn
->dn_next_bonuslen
[i
] = 0;
864 odn
->dn_next_blksz
[i
] = 0;
866 odn
->dn_allocated_txg
= 0;
867 odn
->dn_free_txg
= 0;
868 odn
->dn_assigned_txg
= 0;
869 odn
->dn_dirty_txg
= 0;
870 odn
->dn_dirtyctx
= 0;
871 odn
->dn_dirtyctx_firstset
= NULL
;
872 odn
->dn_have_spill
= B_FALSE
;
875 odn
->dn_oldflags
= 0;
878 odn
->dn_oldprojid
= ZFS_DEFAULT_PROJID
;
881 odn
->dn_newprojid
= ZFS_DEFAULT_PROJID
;
882 odn
->dn_id_flags
= 0;
888 odn
->dn_moved
= (uint8_t)-1;
893 dnode_move(void *buf
, void *newbuf
, size_t size
, void *arg
)
895 dnode_t
*odn
= buf
, *ndn
= newbuf
;
901 * The dnode is on the objset's list of known dnodes if the objset
902 * pointer is valid. We set the low bit of the objset pointer when
903 * freeing the dnode to invalidate it, and the memory patterns written
904 * by kmem (baddcafe and deadbeef) set at least one of the two low bits.
905 * A newly created dnode sets the objset pointer last of all to indicate
906 * that the dnode is known and in a valid state to be moved by this
910 if (!POINTER_IS_VALID(os
)) {
911 DNODE_STAT_BUMP(dnode_move_invalid
);
912 return (KMEM_CBRC_DONT_KNOW
);
916 * Ensure that the objset does not go away during the move.
918 rw_enter(&os_lock
, RW_WRITER
);
919 if (os
!= odn
->dn_objset
) {
921 DNODE_STAT_BUMP(dnode_move_recheck1
);
922 return (KMEM_CBRC_DONT_KNOW
);
926 * If the dnode is still valid, then so is the objset. We know that no
927 * valid objset can be freed while we hold os_lock, so we can safely
928 * ensure that the objset remains in use.
930 mutex_enter(&os
->os_lock
);
933 * Recheck the objset pointer in case the dnode was removed just before
934 * acquiring the lock.
936 if (os
!= odn
->dn_objset
) {
937 mutex_exit(&os
->os_lock
);
939 DNODE_STAT_BUMP(dnode_move_recheck2
);
940 return (KMEM_CBRC_DONT_KNOW
);
944 * At this point we know that as long as we hold os->os_lock, the dnode
945 * cannot be freed and fields within the dnode can be safely accessed.
946 * The objset listing this dnode cannot go away as long as this dnode is
950 if (DMU_OBJECT_IS_SPECIAL(odn
->dn_object
)) {
951 mutex_exit(&os
->os_lock
);
952 DNODE_STAT_BUMP(dnode_move_special
);
953 return (KMEM_CBRC_NO
);
955 ASSERT(odn
->dn_dbuf
!= NULL
); /* only "special" dnodes have no parent */
958 * Lock the dnode handle to prevent the dnode from obtaining any new
959 * holds. This also prevents the descendant dbufs and the bonus dbuf
960 * from accessing the dnode, so that we can discount their holds. The
961 * handle is safe to access because we know that while the dnode cannot
962 * go away, neither can its handle. Once we hold dnh_zrlock, we can
963 * safely move any dnode referenced only by dbufs.
965 if (!zrl_tryenter(&odn
->dn_handle
->dnh_zrlock
)) {
966 mutex_exit(&os
->os_lock
);
967 DNODE_STAT_BUMP(dnode_move_handle
);
968 return (KMEM_CBRC_LATER
);
972 * Ensure a consistent view of the dnode's holds and the dnode's dbufs.
973 * We need to guarantee that there is a hold for every dbuf in order to
974 * determine whether the dnode is actively referenced. Falsely matching
975 * a dbuf to an active hold would lead to an unsafe move. It's possible
976 * that a thread already having an active dnode hold is about to add a
977 * dbuf, and we can't compare hold and dbuf counts while the add is in
980 if (!rw_tryenter(&odn
->dn_struct_rwlock
, RW_WRITER
)) {
981 zrl_exit(&odn
->dn_handle
->dnh_zrlock
);
982 mutex_exit(&os
->os_lock
);
983 DNODE_STAT_BUMP(dnode_move_rwlock
);
984 return (KMEM_CBRC_LATER
);
988 * A dbuf may be removed (evicted) without an active dnode hold. In that
989 * case, the dbuf count is decremented under the handle lock before the
990 * dbuf's hold is released. This order ensures that if we count the hold
991 * after the dbuf is removed but before its hold is released, we will
992 * treat the unmatched hold as active and exit safely. If we count the
993 * hold before the dbuf is removed, the hold is discounted, and the
994 * removal is blocked until the move completes.
996 refcount
= zfs_refcount_count(&odn
->dn_holds
);
997 ASSERT(refcount
>= 0);
998 dbufs
= odn
->dn_dbufs_count
;
1000 /* We can't have more dbufs than dnode holds. */
1001 ASSERT3U(dbufs
, <=, refcount
);
1002 DTRACE_PROBE3(dnode__move
, dnode_t
*, odn
, int64_t, refcount
,
1005 if (refcount
> dbufs
) {
1006 rw_exit(&odn
->dn_struct_rwlock
);
1007 zrl_exit(&odn
->dn_handle
->dnh_zrlock
);
1008 mutex_exit(&os
->os_lock
);
1009 DNODE_STAT_BUMP(dnode_move_active
);
1010 return (KMEM_CBRC_LATER
);
1013 rw_exit(&odn
->dn_struct_rwlock
);
1016 * At this point we know that anyone with a hold on the dnode is not
1017 * actively referencing it. The dnode is known and in a valid state to
1018 * move. We're holding the locks needed to execute the critical section.
1020 dnode_move_impl(odn
, ndn
);
1022 list_link_replace(&odn
->dn_link
, &ndn
->dn_link
);
1023 /* If the dnode was safe to move, the refcount cannot have changed. */
1024 ASSERT(refcount
== zfs_refcount_count(&ndn
->dn_holds
));
1025 ASSERT(dbufs
== ndn
->dn_dbufs_count
);
1026 zrl_exit(&ndn
->dn_handle
->dnh_zrlock
); /* handle has moved */
1027 mutex_exit(&os
->os_lock
);
1029 return (KMEM_CBRC_YES
);
1031 #endif /* _KERNEL */
1034 dnode_slots_hold(dnode_children_t
*children
, int idx
, int slots
)
1036 ASSERT3S(idx
+ slots
, <=, DNODES_PER_BLOCK
);
1038 for (int i
= idx
; i
< idx
+ slots
; i
++) {
1039 dnode_handle_t
*dnh
= &children
->dnc_children
[i
];
1040 zrl_add(&dnh
->dnh_zrlock
);
1045 dnode_slots_rele(dnode_children_t
*children
, int idx
, int slots
)
1047 ASSERT3S(idx
+ slots
, <=, DNODES_PER_BLOCK
);
1049 for (int i
= idx
; i
< idx
+ slots
; i
++) {
1050 dnode_handle_t
*dnh
= &children
->dnc_children
[i
];
1052 if (zrl_is_locked(&dnh
->dnh_zrlock
))
1053 zrl_exit(&dnh
->dnh_zrlock
);
1055 zrl_remove(&dnh
->dnh_zrlock
);
1060 dnode_slots_tryenter(dnode_children_t
*children
, int idx
, int slots
)
1062 ASSERT3S(idx
+ slots
, <=, DNODES_PER_BLOCK
);
1064 for (int i
= idx
; i
< idx
+ slots
; i
++) {
1065 dnode_handle_t
*dnh
= &children
->dnc_children
[i
];
1067 if (!zrl_tryenter(&dnh
->dnh_zrlock
)) {
1068 for (int j
= idx
; j
< i
; j
++) {
1069 dnh
= &children
->dnc_children
[j
];
1070 zrl_exit(&dnh
->dnh_zrlock
);
1081 dnode_set_slots(dnode_children_t
*children
, int idx
, int slots
, void *ptr
)
1083 ASSERT3S(idx
+ slots
, <=, DNODES_PER_BLOCK
);
1085 for (int i
= idx
; i
< idx
+ slots
; i
++) {
1086 dnode_handle_t
*dnh
= &children
->dnc_children
[i
];
1087 dnh
->dnh_dnode
= ptr
;
1092 dnode_check_slots_free(dnode_children_t
*children
, int idx
, int slots
)
1094 ASSERT3S(idx
+ slots
, <=, DNODES_PER_BLOCK
);
1097 * If all dnode slots are either already free or
1098 * evictable return B_TRUE.
1100 for (int i
= idx
; i
< idx
+ slots
; i
++) {
1101 dnode_handle_t
*dnh
= &children
->dnc_children
[i
];
1102 dnode_t
*dn
= dnh
->dnh_dnode
;
1104 if (dn
== DN_SLOT_FREE
) {
1106 } else if (DN_SLOT_IS_PTR(dn
)) {
1107 mutex_enter(&dn
->dn_mtx
);
1108 boolean_t can_free
= (dn
->dn_type
== DMU_OT_NONE
&&
1109 zfs_refcount_is_zero(&dn
->dn_holds
) &&
1110 !DNODE_IS_DIRTY(dn
));
1111 mutex_exit(&dn
->dn_mtx
);
1126 dnode_reclaim_slots(dnode_children_t
*children
, int idx
, int slots
)
1128 ASSERT3S(idx
+ slots
, <=, DNODES_PER_BLOCK
);
1130 for (int i
= idx
; i
< idx
+ slots
; i
++) {
1131 dnode_handle_t
*dnh
= &children
->dnc_children
[i
];
1133 ASSERT(zrl_is_locked(&dnh
->dnh_zrlock
));
1135 if (DN_SLOT_IS_PTR(dnh
->dnh_dnode
)) {
1136 ASSERT3S(dnh
->dnh_dnode
->dn_type
, ==, DMU_OT_NONE
);
1137 dnode_destroy(dnh
->dnh_dnode
);
1138 dnh
->dnh_dnode
= DN_SLOT_FREE
;
1144 dnode_free_interior_slots(dnode_t
*dn
)
1146 dnode_children_t
*children
= dmu_buf_get_user(&dn
->dn_dbuf
->db
);
1147 int epb
= dn
->dn_dbuf
->db
.db_size
>> DNODE_SHIFT
;
1148 int idx
= (dn
->dn_object
& (epb
- 1)) + 1;
1149 int slots
= dn
->dn_num_slots
- 1;
1154 ASSERT3S(idx
+ slots
, <=, DNODES_PER_BLOCK
);
1156 while (!dnode_slots_tryenter(children
, idx
, slots
)) {
1157 DNODE_STAT_BUMP(dnode_free_interior_lock_retry
);
1161 dnode_set_slots(children
, idx
, slots
, DN_SLOT_FREE
);
1162 dnode_slots_rele(children
, idx
, slots
);
1166 dnode_special_close(dnode_handle_t
*dnh
)
1168 dnode_t
*dn
= dnh
->dnh_dnode
;
1171 * Wait for final references to the dnode to clear. This can
1172 * only happen if the arc is asynchronously evicting state that
1173 * has a hold on this dnode while we are trying to evict this
1176 while (zfs_refcount_count(&dn
->dn_holds
) > 0)
1178 ASSERT(dn
->dn_dbuf
== NULL
||
1179 dmu_buf_get_user(&dn
->dn_dbuf
->db
) == NULL
);
1180 zrl_add(&dnh
->dnh_zrlock
);
1181 dnode_destroy(dn
); /* implicit zrl_remove() */
1182 zrl_destroy(&dnh
->dnh_zrlock
);
1183 dnh
->dnh_dnode
= NULL
;
1187 dnode_special_open(objset_t
*os
, dnode_phys_t
*dnp
, uint64_t object
,
1188 dnode_handle_t
*dnh
)
1192 zrl_init(&dnh
->dnh_zrlock
);
1193 zrl_tryenter(&dnh
->dnh_zrlock
);
1195 dn
= dnode_create(os
, dnp
, NULL
, object
, dnh
);
1198 zrl_exit(&dnh
->dnh_zrlock
);
1202 dnode_buf_evict_async(void *dbu
)
1204 dnode_children_t
*dnc
= dbu
;
1206 DNODE_STAT_BUMP(dnode_buf_evict
);
1208 for (int i
= 0; i
< dnc
->dnc_count
; i
++) {
1209 dnode_handle_t
*dnh
= &dnc
->dnc_children
[i
];
1213 * The dnode handle lock guards against the dnode moving to
1214 * another valid address, so there is no need here to guard
1215 * against changes to or from NULL.
1217 if (!DN_SLOT_IS_PTR(dnh
->dnh_dnode
)) {
1218 zrl_destroy(&dnh
->dnh_zrlock
);
1219 dnh
->dnh_dnode
= DN_SLOT_UNINIT
;
1223 zrl_add(&dnh
->dnh_zrlock
);
1224 dn
= dnh
->dnh_dnode
;
1226 * If there are holds on this dnode, then there should
1227 * be holds on the dnode's containing dbuf as well; thus
1228 * it wouldn't be eligible for eviction and this function
1229 * would not have been called.
1231 ASSERT(zfs_refcount_is_zero(&dn
->dn_holds
));
1232 ASSERT(zfs_refcount_is_zero(&dn
->dn_tx_holds
));
1234 dnode_destroy(dn
); /* implicit zrl_remove() for first slot */
1235 zrl_destroy(&dnh
->dnh_zrlock
);
1236 dnh
->dnh_dnode
= DN_SLOT_UNINIT
;
1238 kmem_free(dnc
, sizeof (dnode_children_t
) +
1239 dnc
->dnc_count
* sizeof (dnode_handle_t
));
1243 * When the DNODE_MUST_BE_FREE flag is set, the "slots" parameter is used
1244 * to ensure the hole at the specified object offset is large enough to
1245 * hold the dnode being created. The slots parameter is also used to ensure
1246 * a dnode does not span multiple dnode blocks. In both of these cases, if
1247 * a failure occurs, ENOSPC is returned. Keep in mind, these failure cases
1248 * are only possible when using DNODE_MUST_BE_FREE.
1250 * If the DNODE_MUST_BE_ALLOCATED flag is set, "slots" must be 0.
1251 * dnode_hold_impl() will check if the requested dnode is already consumed
1252 * as an extra dnode slot by an large dnode, in which case it returns
1256 * EINVAL - Invalid object number or flags.
1257 * ENOSPC - Hole too small to fulfill "slots" request (DNODE_MUST_BE_FREE)
1258 * EEXIST - Refers to an allocated dnode (DNODE_MUST_BE_FREE)
1259 * - Refers to a freeing dnode (DNODE_MUST_BE_FREE)
1260 * - Refers to an interior dnode slot (DNODE_MUST_BE_ALLOCATED)
1261 * ENOENT - The requested dnode is not allocated (DNODE_MUST_BE_ALLOCATED)
1262 * - The requested dnode is being freed (DNODE_MUST_BE_ALLOCATED)
1263 * EIO - I/O error when reading the meta dnode dbuf.
1265 * succeeds even for free dnodes.
1268 dnode_hold_impl(objset_t
*os
, uint64_t object
, int flag
, int slots
,
1269 void *tag
, dnode_t
**dnp
)
1272 int drop_struct_lock
= FALSE
;
1277 dnode_children_t
*dnc
;
1278 dnode_phys_t
*dn_block
;
1279 dnode_handle_t
*dnh
;
1281 ASSERT(!(flag
& DNODE_MUST_BE_ALLOCATED
) || (slots
== 0));
1282 ASSERT(!(flag
& DNODE_MUST_BE_FREE
) || (slots
> 0));
1285 * If you are holding the spa config lock as writer, you shouldn't
1286 * be asking the DMU to do *anything* unless it's the root pool
1287 * which may require us to read from the root filesystem while
1288 * holding some (not all) of the locks as writer.
1290 ASSERT(spa_config_held(os
->os_spa
, SCL_ALL
, RW_WRITER
) == 0 ||
1291 (spa_is_root(os
->os_spa
) &&
1292 spa_config_held(os
->os_spa
, SCL_STATE
, RW_WRITER
)));
1294 ASSERT((flag
& DNODE_MUST_BE_ALLOCATED
) || (flag
& DNODE_MUST_BE_FREE
));
1296 if (object
== DMU_USERUSED_OBJECT
|| object
== DMU_GROUPUSED_OBJECT
||
1297 object
== DMU_PROJECTUSED_OBJECT
) {
1298 if (object
== DMU_USERUSED_OBJECT
)
1299 dn
= DMU_USERUSED_DNODE(os
);
1300 else if (object
== DMU_GROUPUSED_OBJECT
)
1301 dn
= DMU_GROUPUSED_DNODE(os
);
1303 dn
= DMU_PROJECTUSED_DNODE(os
);
1305 return (SET_ERROR(ENOENT
));
1307 if ((flag
& DNODE_MUST_BE_ALLOCATED
) && type
== DMU_OT_NONE
)
1308 return (SET_ERROR(ENOENT
));
1309 if ((flag
& DNODE_MUST_BE_FREE
) && type
!= DMU_OT_NONE
)
1310 return (SET_ERROR(EEXIST
));
1312 (void) zfs_refcount_add(&dn
->dn_holds
, tag
);
1317 if (object
== 0 || object
>= DN_MAX_OBJECT
)
1318 return (SET_ERROR(EINVAL
));
1320 mdn
= DMU_META_DNODE(os
);
1321 ASSERT(mdn
->dn_object
== DMU_META_DNODE_OBJECT
);
1325 if (!RW_WRITE_HELD(&mdn
->dn_struct_rwlock
)) {
1326 rw_enter(&mdn
->dn_struct_rwlock
, RW_READER
);
1327 drop_struct_lock
= TRUE
;
1330 blk
= dbuf_whichblock(mdn
, 0, object
* sizeof (dnode_phys_t
));
1332 db
= dbuf_hold(mdn
, blk
, FTAG
);
1333 if (drop_struct_lock
)
1334 rw_exit(&mdn
->dn_struct_rwlock
);
1336 DNODE_STAT_BUMP(dnode_hold_dbuf_hold
);
1337 return (SET_ERROR(EIO
));
1341 * We do not need to decrypt to read the dnode so it doesn't matter
1342 * if we get the encrypted or decrypted version.
1344 err
= dbuf_read(db
, NULL
, DB_RF_CANFAIL
| DB_RF_NO_DECRYPT
);
1346 DNODE_STAT_BUMP(dnode_hold_dbuf_read
);
1347 dbuf_rele(db
, FTAG
);
1351 ASSERT3U(db
->db
.db_size
, >=, 1<<DNODE_SHIFT
);
1352 epb
= db
->db
.db_size
>> DNODE_SHIFT
;
1354 idx
= object
& (epb
- 1);
1355 dn_block
= (dnode_phys_t
*)db
->db
.db_data
;
1357 ASSERT(DB_DNODE(db
)->dn_type
== DMU_OT_DNODE
);
1358 dnc
= dmu_buf_get_user(&db
->db
);
1361 dnode_children_t
*winner
;
1364 dnc
= kmem_zalloc(sizeof (dnode_children_t
) +
1365 epb
* sizeof (dnode_handle_t
), KM_SLEEP
);
1366 dnc
->dnc_count
= epb
;
1367 dnh
= &dnc
->dnc_children
[0];
1369 /* Initialize dnode slot status from dnode_phys_t */
1370 for (int i
= 0; i
< epb
; i
++) {
1371 zrl_init(&dnh
[i
].dnh_zrlock
);
1378 if (dn_block
[i
].dn_type
!= DMU_OT_NONE
) {
1379 int interior
= dn_block
[i
].dn_extra_slots
;
1381 dnode_set_slots(dnc
, i
, 1, DN_SLOT_ALLOCATED
);
1382 dnode_set_slots(dnc
, i
+ 1, interior
,
1386 dnh
[i
].dnh_dnode
= DN_SLOT_FREE
;
1391 dmu_buf_init_user(&dnc
->dnc_dbu
, NULL
,
1392 dnode_buf_evict_async
, NULL
);
1393 winner
= dmu_buf_set_user(&db
->db
, &dnc
->dnc_dbu
);
1394 if (winner
!= NULL
) {
1396 for (int i
= 0; i
< epb
; i
++)
1397 zrl_destroy(&dnh
[i
].dnh_zrlock
);
1399 kmem_free(dnc
, sizeof (dnode_children_t
) +
1400 epb
* sizeof (dnode_handle_t
));
1405 ASSERT(dnc
->dnc_count
== epb
);
1407 if (flag
& DNODE_MUST_BE_ALLOCATED
) {
1410 dnode_slots_hold(dnc
, idx
, slots
);
1411 dnh
= &dnc
->dnc_children
[idx
];
1413 if (DN_SLOT_IS_PTR(dnh
->dnh_dnode
)) {
1414 dn
= dnh
->dnh_dnode
;
1415 } else if (dnh
->dnh_dnode
== DN_SLOT_INTERIOR
) {
1416 DNODE_STAT_BUMP(dnode_hold_alloc_interior
);
1417 dnode_slots_rele(dnc
, idx
, slots
);
1418 dbuf_rele(db
, FTAG
);
1419 return (SET_ERROR(EEXIST
));
1420 } else if (dnh
->dnh_dnode
!= DN_SLOT_ALLOCATED
) {
1421 DNODE_STAT_BUMP(dnode_hold_alloc_misses
);
1422 dnode_slots_rele(dnc
, idx
, slots
);
1423 dbuf_rele(db
, FTAG
);
1424 return (SET_ERROR(ENOENT
));
1426 dnode_slots_rele(dnc
, idx
, slots
);
1427 while (!dnode_slots_tryenter(dnc
, idx
, slots
)) {
1428 DNODE_STAT_BUMP(dnode_hold_alloc_lock_retry
);
1433 * Someone else won the race and called dnode_create()
1434 * after we checked DN_SLOT_IS_PTR() above but before
1435 * we acquired the lock.
1437 if (DN_SLOT_IS_PTR(dnh
->dnh_dnode
)) {
1438 DNODE_STAT_BUMP(dnode_hold_alloc_lock_misses
);
1439 dn
= dnh
->dnh_dnode
;
1441 dn
= dnode_create(os
, dn_block
+ idx
, db
,
1446 mutex_enter(&dn
->dn_mtx
);
1447 if (dn
->dn_type
== DMU_OT_NONE
|| dn
->dn_free_txg
!= 0) {
1448 DNODE_STAT_BUMP(dnode_hold_alloc_type_none
);
1449 mutex_exit(&dn
->dn_mtx
);
1450 dnode_slots_rele(dnc
, idx
, slots
);
1451 dbuf_rele(db
, FTAG
);
1452 return (SET_ERROR(ENOENT
));
1455 DNODE_STAT_BUMP(dnode_hold_alloc_hits
);
1456 } else if (flag
& DNODE_MUST_BE_FREE
) {
1458 if (idx
+ slots
- 1 >= DNODES_PER_BLOCK
) {
1459 DNODE_STAT_BUMP(dnode_hold_free_overflow
);
1460 dbuf_rele(db
, FTAG
);
1461 return (SET_ERROR(ENOSPC
));
1464 dnode_slots_hold(dnc
, idx
, slots
);
1466 if (!dnode_check_slots_free(dnc
, idx
, slots
)) {
1467 DNODE_STAT_BUMP(dnode_hold_free_misses
);
1468 dnode_slots_rele(dnc
, idx
, slots
);
1469 dbuf_rele(db
, FTAG
);
1470 return (SET_ERROR(ENOSPC
));
1473 dnode_slots_rele(dnc
, idx
, slots
);
1474 while (!dnode_slots_tryenter(dnc
, idx
, slots
)) {
1475 DNODE_STAT_BUMP(dnode_hold_free_lock_retry
);
1479 if (!dnode_check_slots_free(dnc
, idx
, slots
)) {
1480 DNODE_STAT_BUMP(dnode_hold_free_lock_misses
);
1481 dnode_slots_rele(dnc
, idx
, slots
);
1482 dbuf_rele(db
, FTAG
);
1483 return (SET_ERROR(ENOSPC
));
1487 * Allocated but otherwise free dnodes which would
1488 * be in the interior of a multi-slot dnodes need
1489 * to be freed. Single slot dnodes can be safely
1490 * re-purposed as a performance optimization.
1493 dnode_reclaim_slots(dnc
, idx
+ 1, slots
- 1);
1495 dnh
= &dnc
->dnc_children
[idx
];
1496 if (DN_SLOT_IS_PTR(dnh
->dnh_dnode
)) {
1497 dn
= dnh
->dnh_dnode
;
1499 dn
= dnode_create(os
, dn_block
+ idx
, db
,
1503 mutex_enter(&dn
->dn_mtx
);
1504 if (!zfs_refcount_is_zero(&dn
->dn_holds
) || dn
->dn_free_txg
) {
1505 DNODE_STAT_BUMP(dnode_hold_free_refcount
);
1506 mutex_exit(&dn
->dn_mtx
);
1507 dnode_slots_rele(dnc
, idx
, slots
);
1508 dbuf_rele(db
, FTAG
);
1509 return (SET_ERROR(EEXIST
));
1512 dnode_set_slots(dnc
, idx
+ 1, slots
- 1, DN_SLOT_INTERIOR
);
1513 DNODE_STAT_BUMP(dnode_hold_free_hits
);
1515 dbuf_rele(db
, FTAG
);
1516 return (SET_ERROR(EINVAL
));
1519 if (dn
->dn_free_txg
) {
1520 DNODE_STAT_BUMP(dnode_hold_free_txg
);
1522 mutex_exit(&dn
->dn_mtx
);
1523 dnode_slots_rele(dnc
, idx
, slots
);
1524 dbuf_rele(db
, FTAG
);
1525 return (SET_ERROR((flag
& DNODE_MUST_BE_ALLOCATED
) ?
1529 if (zfs_refcount_add(&dn
->dn_holds
, tag
) == 1)
1530 dbuf_add_ref(db
, dnh
);
1532 mutex_exit(&dn
->dn_mtx
);
1534 /* Now we can rely on the hold to prevent the dnode from moving. */
1535 dnode_slots_rele(dnc
, idx
, slots
);
1538 ASSERT3P(dn
->dn_dbuf
, ==, db
);
1539 ASSERT3U(dn
->dn_object
, ==, object
);
1540 dbuf_rele(db
, FTAG
);
1547 * Return held dnode if the object is allocated, NULL if not.
1550 dnode_hold(objset_t
*os
, uint64_t object
, void *tag
, dnode_t
**dnp
)
1552 return (dnode_hold_impl(os
, object
, DNODE_MUST_BE_ALLOCATED
, 0, tag
,
1557 * Can only add a reference if there is already at least one
1558 * reference on the dnode. Returns FALSE if unable to add a
1562 dnode_add_ref(dnode_t
*dn
, void *tag
)
1564 mutex_enter(&dn
->dn_mtx
);
1565 if (zfs_refcount_is_zero(&dn
->dn_holds
)) {
1566 mutex_exit(&dn
->dn_mtx
);
1569 VERIFY(1 < zfs_refcount_add(&dn
->dn_holds
, tag
));
1570 mutex_exit(&dn
->dn_mtx
);
1575 dnode_rele(dnode_t
*dn
, void *tag
)
1577 mutex_enter(&dn
->dn_mtx
);
1578 dnode_rele_and_unlock(dn
, tag
, B_FALSE
);
1582 dnode_rele_and_unlock(dnode_t
*dn
, void *tag
, boolean_t evicting
)
1585 /* Get while the hold prevents the dnode from moving. */
1586 dmu_buf_impl_t
*db
= dn
->dn_dbuf
;
1587 dnode_handle_t
*dnh
= dn
->dn_handle
;
1589 refs
= zfs_refcount_remove(&dn
->dn_holds
, tag
);
1590 mutex_exit(&dn
->dn_mtx
);
1593 * It's unsafe to release the last hold on a dnode by dnode_rele() or
1594 * indirectly by dbuf_rele() while relying on the dnode handle to
1595 * prevent the dnode from moving, since releasing the last hold could
1596 * result in the dnode's parent dbuf evicting its dnode handles. For
1597 * that reason anyone calling dnode_rele() or dbuf_rele() without some
1598 * other direct or indirect hold on the dnode must first drop the dnode
1601 ASSERT(refs
> 0 || dnh
->dnh_zrlock
.zr_owner
!= curthread
);
1603 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */
1604 if (refs
== 0 && db
!= NULL
) {
1606 * Another thread could add a hold to the dnode handle in
1607 * dnode_hold_impl() while holding the parent dbuf. Since the
1608 * hold on the parent dbuf prevents the handle from being
1609 * destroyed, the hold on the handle is OK. We can't yet assert
1610 * that the handle has zero references, but that will be
1611 * asserted anyway when the handle gets destroyed.
1613 mutex_enter(&db
->db_mtx
);
1614 dbuf_rele_and_unlock(db
, dnh
, evicting
);
1619 dnode_setdirty(dnode_t
*dn
, dmu_tx_t
*tx
)
1621 objset_t
*os
= dn
->dn_objset
;
1622 uint64_t txg
= tx
->tx_txg
;
1624 if (DMU_OBJECT_IS_SPECIAL(dn
->dn_object
)) {
1625 dsl_dataset_dirty(os
->os_dsl_dataset
, tx
);
1632 mutex_enter(&dn
->dn_mtx
);
1633 ASSERT(dn
->dn_phys
->dn_type
|| dn
->dn_allocated_txg
);
1634 ASSERT(dn
->dn_free_txg
== 0 || dn
->dn_free_txg
>= txg
);
1635 mutex_exit(&dn
->dn_mtx
);
1639 * Determine old uid/gid when necessary
1641 dmu_objset_userquota_get_ids(dn
, B_TRUE
, tx
);
1643 multilist_t
*dirtylist
= os
->os_dirty_dnodes
[txg
& TXG_MASK
];
1644 multilist_sublist_t
*mls
= multilist_sublist_lock_obj(dirtylist
, dn
);
1647 * If we are already marked dirty, we're done.
1649 if (multilist_link_active(&dn
->dn_dirty_link
[txg
& TXG_MASK
])) {
1650 multilist_sublist_unlock(mls
);
1654 ASSERT(!zfs_refcount_is_zero(&dn
->dn_holds
) ||
1655 !avl_is_empty(&dn
->dn_dbufs
));
1656 ASSERT(dn
->dn_datablksz
!= 0);
1657 ASSERT0(dn
->dn_next_bonuslen
[txg
&TXG_MASK
]);
1658 ASSERT0(dn
->dn_next_blksz
[txg
&TXG_MASK
]);
1659 ASSERT0(dn
->dn_next_bonustype
[txg
&TXG_MASK
]);
1661 dprintf_ds(os
->os_dsl_dataset
, "obj=%llu txg=%llu\n",
1662 dn
->dn_object
, txg
);
1664 multilist_sublist_insert_head(mls
, dn
);
1666 multilist_sublist_unlock(mls
);
1669 * The dnode maintains a hold on its containing dbuf as
1670 * long as there are holds on it. Each instantiated child
1671 * dbuf maintains a hold on the dnode. When the last child
1672 * drops its hold, the dnode will drop its hold on the
1673 * containing dbuf. We add a "dirty hold" here so that the
1674 * dnode will hang around after we finish processing its
1677 VERIFY(dnode_add_ref(dn
, (void *)(uintptr_t)tx
->tx_txg
));
1679 (void) dbuf_dirty(dn
->dn_dbuf
, tx
);
1681 dsl_dataset_dirty(os
->os_dsl_dataset
, tx
);
1685 dnode_free(dnode_t
*dn
, dmu_tx_t
*tx
)
1687 mutex_enter(&dn
->dn_mtx
);
1688 if (dn
->dn_type
== DMU_OT_NONE
|| dn
->dn_free_txg
) {
1689 mutex_exit(&dn
->dn_mtx
);
1692 dn
->dn_free_txg
= tx
->tx_txg
;
1693 mutex_exit(&dn
->dn_mtx
);
1695 dnode_setdirty(dn
, tx
);
1699 * Try to change the block size for the indicated dnode. This can only
1700 * succeed if there are no blocks allocated or dirty beyond first block
1703 dnode_set_blksz(dnode_t
*dn
, uint64_t size
, int ibs
, dmu_tx_t
*tx
)
1708 ASSERT3U(size
, <=, spa_maxblocksize(dmu_objset_spa(dn
->dn_objset
)));
1710 size
= SPA_MINBLOCKSIZE
;
1712 size
= P2ROUNDUP(size
, SPA_MINBLOCKSIZE
);
1714 if (ibs
== dn
->dn_indblkshift
)
1717 if (size
>> SPA_MINBLOCKSHIFT
== dn
->dn_datablkszsec
&& ibs
== 0)
1720 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
1722 /* Check for any allocated blocks beyond the first */
1723 if (dn
->dn_maxblkid
!= 0)
1726 mutex_enter(&dn
->dn_dbufs_mtx
);
1727 for (db
= avl_first(&dn
->dn_dbufs
); db
!= NULL
;
1728 db
= AVL_NEXT(&dn
->dn_dbufs
, db
)) {
1729 if (db
->db_blkid
!= 0 && db
->db_blkid
!= DMU_BONUS_BLKID
&&
1730 db
->db_blkid
!= DMU_SPILL_BLKID
) {
1731 mutex_exit(&dn
->dn_dbufs_mtx
);
1735 mutex_exit(&dn
->dn_dbufs_mtx
);
1737 if (ibs
&& dn
->dn_nlevels
!= 1)
1740 /* resize the old block */
1741 err
= dbuf_hold_impl(dn
, 0, 0, TRUE
, FALSE
, FTAG
, &db
);
1743 dbuf_new_size(db
, size
, tx
);
1744 else if (err
!= ENOENT
)
1747 dnode_setdblksz(dn
, size
);
1748 dnode_setdirty(dn
, tx
);
1749 dn
->dn_next_blksz
[tx
->tx_txg
&TXG_MASK
] = size
;
1751 dn
->dn_indblkshift
= ibs
;
1752 dn
->dn_next_indblkshift
[tx
->tx_txg
&TXG_MASK
] = ibs
;
1754 /* rele after we have fixed the blocksize in the dnode */
1756 dbuf_rele(db
, FTAG
);
1758 rw_exit(&dn
->dn_struct_rwlock
);
1762 rw_exit(&dn
->dn_struct_rwlock
);
1763 return (SET_ERROR(ENOTSUP
));
1767 dnode_set_nlevels_impl(dnode_t
*dn
, int new_nlevels
, dmu_tx_t
*tx
)
1769 uint64_t txgoff
= tx
->tx_txg
& TXG_MASK
;
1770 int old_nlevels
= dn
->dn_nlevels
;
1773 dbuf_dirty_record_t
*new, *dr
, *dr_next
;
1775 ASSERT(RW_WRITE_HELD(&dn
->dn_struct_rwlock
));
1777 dn
->dn_nlevels
= new_nlevels
;
1779 ASSERT3U(new_nlevels
, >, dn
->dn_next_nlevels
[txgoff
]);
1780 dn
->dn_next_nlevels
[txgoff
] = new_nlevels
;
1782 /* dirty the left indirects */
1783 db
= dbuf_hold_level(dn
, old_nlevels
, 0, FTAG
);
1785 new = dbuf_dirty(db
, tx
);
1786 dbuf_rele(db
, FTAG
);
1788 /* transfer the dirty records to the new indirect */
1789 mutex_enter(&dn
->dn_mtx
);
1790 mutex_enter(&new->dt
.di
.dr_mtx
);
1791 list
= &dn
->dn_dirty_records
[txgoff
];
1792 for (dr
= list_head(list
); dr
; dr
= dr_next
) {
1793 dr_next
= list_next(&dn
->dn_dirty_records
[txgoff
], dr
);
1794 if (dr
->dr_dbuf
->db_level
!= new_nlevels
-1 &&
1795 dr
->dr_dbuf
->db_blkid
!= DMU_BONUS_BLKID
&&
1796 dr
->dr_dbuf
->db_blkid
!= DMU_SPILL_BLKID
) {
1797 ASSERT(dr
->dr_dbuf
->db_level
== old_nlevels
-1);
1798 list_remove(&dn
->dn_dirty_records
[txgoff
], dr
);
1799 list_insert_tail(&new->dt
.di
.dr_children
, dr
);
1800 dr
->dr_parent
= new;
1803 mutex_exit(&new->dt
.di
.dr_mtx
);
1804 mutex_exit(&dn
->dn_mtx
);
1808 dnode_set_nlevels(dnode_t
*dn
, int nlevels
, dmu_tx_t
*tx
)
1812 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
1814 if (dn
->dn_nlevels
== nlevels
) {
1817 } else if (nlevels
< dn
->dn_nlevels
) {
1818 ret
= SET_ERROR(EINVAL
);
1822 dnode_set_nlevels_impl(dn
, nlevels
, tx
);
1825 rw_exit(&dn
->dn_struct_rwlock
);
1829 /* read-holding callers must not rely on the lock being continuously held */
1831 dnode_new_blkid(dnode_t
*dn
, uint64_t blkid
, dmu_tx_t
*tx
, boolean_t have_read
,
1834 int epbs
, new_nlevels
;
1837 ASSERT(blkid
!= DMU_BONUS_BLKID
);
1840 RW_READ_HELD(&dn
->dn_struct_rwlock
) :
1841 RW_WRITE_HELD(&dn
->dn_struct_rwlock
));
1844 * if we have a read-lock, check to see if we need to do any work
1845 * before upgrading to a write-lock.
1848 if (blkid
<= dn
->dn_maxblkid
)
1851 if (!rw_tryupgrade(&dn
->dn_struct_rwlock
)) {
1852 rw_exit(&dn
->dn_struct_rwlock
);
1853 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
1858 * Raw sends (indicated by the force flag) require that we take the
1859 * given blkid even if the value is lower than the current value.
1861 if (!force
&& blkid
<= dn
->dn_maxblkid
)
1865 * We use the (otherwise unused) top bit of dn_next_maxblkid[txgoff]
1866 * to indicate that this field is set. This allows us to set the
1867 * maxblkid to 0 on an existing object in dnode_sync().
1869 dn
->dn_maxblkid
= blkid
;
1870 dn
->dn_next_maxblkid
[tx
->tx_txg
& TXG_MASK
] =
1871 blkid
| DMU_NEXT_MAXBLKID_SET
;
1874 * Compute the number of levels necessary to support the new maxblkid.
1875 * Raw sends will ensure nlevels is set correctly for us.
1878 epbs
= dn
->dn_indblkshift
- SPA_BLKPTRSHIFT
;
1879 for (sz
= dn
->dn_nblkptr
;
1880 sz
<= blkid
&& sz
>= dn
->dn_nblkptr
; sz
<<= epbs
)
1883 ASSERT3U(new_nlevels
, <=, DN_MAX_LEVELS
);
1886 if (new_nlevels
> dn
->dn_nlevels
)
1887 dnode_set_nlevels_impl(dn
, new_nlevels
, tx
);
1889 ASSERT3U(dn
->dn_nlevels
, >=, new_nlevels
);
1894 rw_downgrade(&dn
->dn_struct_rwlock
);
1898 dnode_dirty_l1(dnode_t
*dn
, uint64_t l1blkid
, dmu_tx_t
*tx
)
1900 dmu_buf_impl_t
*db
= dbuf_hold_level(dn
, 1, l1blkid
, FTAG
);
1902 dmu_buf_will_dirty(&db
->db
, tx
);
1903 dbuf_rele(db
, FTAG
);
1908 * Dirty all the in-core level-1 dbufs in the range specified by start_blkid
1912 dnode_dirty_l1range(dnode_t
*dn
, uint64_t start_blkid
, uint64_t end_blkid
,
1915 dmu_buf_impl_t db_search
;
1919 mutex_enter(&dn
->dn_dbufs_mtx
);
1921 db_search
.db_level
= 1;
1922 db_search
.db_blkid
= start_blkid
+ 1;
1923 db_search
.db_state
= DB_SEARCH
;
1926 db
= avl_find(&dn
->dn_dbufs
, &db_search
, &where
);
1928 db
= avl_nearest(&dn
->dn_dbufs
, where
, AVL_AFTER
);
1930 if (db
== NULL
|| db
->db_level
!= 1 ||
1931 db
->db_blkid
>= end_blkid
) {
1936 * Setup the next blkid we want to search for.
1938 db_search
.db_blkid
= db
->db_blkid
+ 1;
1939 ASSERT3U(db
->db_blkid
, >=, start_blkid
);
1942 * If the dbuf transitions to DB_EVICTING while we're trying
1943 * to dirty it, then we will be unable to discover it in
1944 * the dbuf hash table. This will result in a call to
1945 * dbuf_create() which needs to acquire the dn_dbufs_mtx
1946 * lock. To avoid a deadlock, we drop the lock before
1947 * dirtying the level-1 dbuf.
1949 mutex_exit(&dn
->dn_dbufs_mtx
);
1950 dnode_dirty_l1(dn
, db
->db_blkid
, tx
);
1951 mutex_enter(&dn
->dn_dbufs_mtx
);
1956 * Walk all the in-core level-1 dbufs and verify they have been dirtied.
1958 db_search
.db_level
= 1;
1959 db_search
.db_blkid
= start_blkid
+ 1;
1960 db_search
.db_state
= DB_SEARCH
;
1961 db
= avl_find(&dn
->dn_dbufs
, &db_search
, &where
);
1963 db
= avl_nearest(&dn
->dn_dbufs
, where
, AVL_AFTER
);
1964 for (; db
!= NULL
; db
= AVL_NEXT(&dn
->dn_dbufs
, db
)) {
1965 if (db
->db_level
!= 1 || db
->db_blkid
>= end_blkid
)
1967 ASSERT(db
->db_dirtycnt
> 0);
1970 mutex_exit(&dn
->dn_dbufs_mtx
);
1974 dnode_free_range(dnode_t
*dn
, uint64_t off
, uint64_t len
, dmu_tx_t
*tx
)
1977 uint64_t blkoff
, blkid
, nblks
;
1978 int blksz
, blkshift
, head
, tail
;
1982 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
1983 blksz
= dn
->dn_datablksz
;
1984 blkshift
= dn
->dn_datablkshift
;
1985 epbs
= dn
->dn_indblkshift
- SPA_BLKPTRSHIFT
;
1987 if (len
== DMU_OBJECT_END
) {
1988 len
= UINT64_MAX
- off
;
1993 * First, block align the region to free:
1996 head
= P2NPHASE(off
, blksz
);
1997 blkoff
= P2PHASE(off
, blksz
);
1998 if ((off
>> blkshift
) > dn
->dn_maxblkid
)
2001 ASSERT(dn
->dn_maxblkid
== 0);
2002 if (off
== 0 && len
>= blksz
) {
2004 * Freeing the whole block; fast-track this request.
2008 if (dn
->dn_nlevels
> 1)
2009 dnode_dirty_l1(dn
, 0, tx
);
2011 } else if (off
>= blksz
) {
2012 /* Freeing past end-of-data */
2015 /* Freeing part of the block. */
2017 ASSERT3U(head
, >, 0);
2021 /* zero out any partial block data at the start of the range */
2023 ASSERT3U(blkoff
+ head
, ==, blksz
);
2026 if (dbuf_hold_impl(dn
, 0, dbuf_whichblock(dn
, 0, off
),
2027 TRUE
, FALSE
, FTAG
, &db
) == 0) {
2030 /* don't dirty if it isn't on disk and isn't dirty */
2031 if (db
->db_last_dirty
||
2032 (db
->db_blkptr
&& !BP_IS_HOLE(db
->db_blkptr
))) {
2033 rw_exit(&dn
->dn_struct_rwlock
);
2034 dmu_buf_will_dirty(&db
->db
, tx
);
2035 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
2036 data
= db
->db
.db_data
;
2037 bzero(data
+ blkoff
, head
);
2039 dbuf_rele(db
, FTAG
);
2045 /* If the range was less than one block, we're done */
2049 /* If the remaining range is past end of file, we're done */
2050 if ((off
>> blkshift
) > dn
->dn_maxblkid
)
2053 ASSERT(ISP2(blksz
));
2057 tail
= P2PHASE(len
, blksz
);
2059 ASSERT0(P2PHASE(off
, blksz
));
2060 /* zero out any partial block data at the end of the range */
2064 if (dbuf_hold_impl(dn
, 0, dbuf_whichblock(dn
, 0, off
+len
),
2065 TRUE
, FALSE
, FTAG
, &db
) == 0) {
2066 /* don't dirty if not on disk and not dirty */
2067 if (db
->db_last_dirty
||
2068 (db
->db_blkptr
&& !BP_IS_HOLE(db
->db_blkptr
))) {
2069 rw_exit(&dn
->dn_struct_rwlock
);
2070 dmu_buf_will_dirty(&db
->db
, tx
);
2071 rw_enter(&dn
->dn_struct_rwlock
, RW_WRITER
);
2072 bzero(db
->db
.db_data
, tail
);
2074 dbuf_rele(db
, FTAG
);
2079 /* If the range did not include a full block, we are done */
2083 ASSERT(IS_P2ALIGNED(off
, blksz
));
2084 ASSERT(trunc
|| IS_P2ALIGNED(len
, blksz
));
2085 blkid
= off
>> blkshift
;
2086 nblks
= len
>> blkshift
;
2091 * Dirty all the indirect blocks in this range. Note that only
2092 * the first and last indirect blocks can actually be written
2093 * (if they were partially freed) -- they must be dirtied, even if
2094 * they do not exist on disk yet. The interior blocks will
2095 * be freed by free_children(), so they will not actually be written.
2096 * Even though these interior blocks will not be written, we
2097 * dirty them for two reasons:
2099 * - It ensures that the indirect blocks remain in memory until
2100 * syncing context. (They have already been prefetched by
2101 * dmu_tx_hold_free(), so we don't have to worry about reading
2102 * them serially here.)
2104 * - The dirty space accounting will put pressure on the txg sync
2105 * mechanism to begin syncing, and to delay transactions if there
2106 * is a large amount of freeing. Even though these indirect
2107 * blocks will not be written, we could need to write the same
2108 * amount of space if we copy the freed BPs into deadlists.
2110 if (dn
->dn_nlevels
> 1) {
2111 uint64_t first
, last
;
2113 first
= blkid
>> epbs
;
2114 dnode_dirty_l1(dn
, first
, tx
);
2116 last
= dn
->dn_maxblkid
>> epbs
;
2118 last
= (blkid
+ nblks
- 1) >> epbs
;
2120 dnode_dirty_l1(dn
, last
, tx
);
2122 dnode_dirty_l1range(dn
, first
, last
, tx
);
2124 int shift
= dn
->dn_datablkshift
+ dn
->dn_indblkshift
-
2126 for (uint64_t i
= first
+ 1; i
< last
; i
++) {
2128 * Set i to the blockid of the next non-hole
2129 * level-1 indirect block at or after i. Note
2130 * that dnode_next_offset() operates in terms of
2131 * level-0-equivalent bytes.
2133 uint64_t ibyte
= i
<< shift
;
2134 int err
= dnode_next_offset(dn
, DNODE_FIND_HAVELOCK
,
2141 * Normally we should not see an error, either
2142 * from dnode_next_offset() or dbuf_hold_level()
2143 * (except for ESRCH from dnode_next_offset).
2144 * If there is an i/o error, then when we read
2145 * this block in syncing context, it will use
2146 * ZIO_FLAG_MUSTSUCCEED, and thus hang/panic according
2147 * to the "failmode" property. dnode_next_offset()
2148 * doesn't have a flag to indicate MUSTSUCCEED.
2153 dnode_dirty_l1(dn
, i
, tx
);
2159 * Add this range to the dnode range list.
2160 * We will finish up this free operation in the syncing phase.
2162 mutex_enter(&dn
->dn_mtx
);
2164 int txgoff
= tx
->tx_txg
& TXG_MASK
;
2165 if (dn
->dn_free_ranges
[txgoff
] == NULL
) {
2166 dn
->dn_free_ranges
[txgoff
] = range_tree_create(NULL
, NULL
);
2168 range_tree_clear(dn
->dn_free_ranges
[txgoff
], blkid
, nblks
);
2169 range_tree_add(dn
->dn_free_ranges
[txgoff
], blkid
, nblks
);
2171 dprintf_dnode(dn
, "blkid=%llu nblks=%llu txg=%llu\n",
2172 blkid
, nblks
, tx
->tx_txg
);
2173 mutex_exit(&dn
->dn_mtx
);
2175 dbuf_free_range(dn
, blkid
, blkid
+ nblks
- 1, tx
);
2176 dnode_setdirty(dn
, tx
);
2179 rw_exit(&dn
->dn_struct_rwlock
);
2183 dnode_spill_freed(dnode_t
*dn
)
2187 mutex_enter(&dn
->dn_mtx
);
2188 for (i
= 0; i
< TXG_SIZE
; i
++) {
2189 if (dn
->dn_rm_spillblk
[i
] == DN_KILL_SPILLBLK
)
2192 mutex_exit(&dn
->dn_mtx
);
2193 return (i
< TXG_SIZE
);
2196 /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */
2198 dnode_block_freed(dnode_t
*dn
, uint64_t blkid
)
2200 void *dp
= spa_get_dsl(dn
->dn_objset
->os_spa
);
2203 if (blkid
== DMU_BONUS_BLKID
)
2207 * If we're in the process of opening the pool, dp will not be
2208 * set yet, but there shouldn't be anything dirty.
2213 if (dn
->dn_free_txg
)
2216 if (blkid
== DMU_SPILL_BLKID
)
2217 return (dnode_spill_freed(dn
));
2219 mutex_enter(&dn
->dn_mtx
);
2220 for (i
= 0; i
< TXG_SIZE
; i
++) {
2221 if (dn
->dn_free_ranges
[i
] != NULL
&&
2222 range_tree_contains(dn
->dn_free_ranges
[i
], blkid
, 1))
2225 mutex_exit(&dn
->dn_mtx
);
2226 return (i
< TXG_SIZE
);
2229 /* call from syncing context when we actually write/free space for this dnode */
2231 dnode_diduse_space(dnode_t
*dn
, int64_t delta
)
2234 dprintf_dnode(dn
, "dn=%p dnp=%p used=%llu delta=%lld\n",
2236 (u_longlong_t
)dn
->dn_phys
->dn_used
,
2239 mutex_enter(&dn
->dn_mtx
);
2240 space
= DN_USED_BYTES(dn
->dn_phys
);
2242 ASSERT3U(space
+ delta
, >=, space
); /* no overflow */
2244 ASSERT3U(space
, >=, -delta
); /* no underflow */
2247 if (spa_version(dn
->dn_objset
->os_spa
) < SPA_VERSION_DNODE_BYTES
) {
2248 ASSERT((dn
->dn_phys
->dn_flags
& DNODE_FLAG_USED_BYTES
) == 0);
2249 ASSERT0(P2PHASE(space
, 1<<DEV_BSHIFT
));
2250 dn
->dn_phys
->dn_used
= space
>> DEV_BSHIFT
;
2252 dn
->dn_phys
->dn_used
= space
;
2253 dn
->dn_phys
->dn_flags
|= DNODE_FLAG_USED_BYTES
;
2255 mutex_exit(&dn
->dn_mtx
);
2259 * Scans a block at the indicated "level" looking for a hole or data,
2260 * depending on 'flags'.
2262 * If level > 0, then we are scanning an indirect block looking at its
2263 * pointers. If level == 0, then we are looking at a block of dnodes.
2265 * If we don't find what we are looking for in the block, we return ESRCH.
2266 * Otherwise, return with *offset pointing to the beginning (if searching
2267 * forwards) or end (if searching backwards) of the range covered by the
2268 * block pointer we matched on (or dnode).
2270 * The basic search algorithm used below by dnode_next_offset() is to
2271 * use this function to search up the block tree (widen the search) until
2272 * we find something (i.e., we don't return ESRCH) and then search back
2273 * down the tree (narrow the search) until we reach our original search
2277 dnode_next_offset_level(dnode_t
*dn
, int flags
, uint64_t *offset
,
2278 int lvl
, uint64_t blkfill
, uint64_t txg
)
2280 dmu_buf_impl_t
*db
= NULL
;
2282 uint64_t epbs
= dn
->dn_phys
->dn_indblkshift
- SPA_BLKPTRSHIFT
;
2283 uint64_t epb
= 1ULL << epbs
;
2284 uint64_t minfill
, maxfill
;
2286 int i
, inc
, error
, span
;
2288 hole
= ((flags
& DNODE_FIND_HOLE
) != 0);
2289 inc
= (flags
& DNODE_FIND_BACKWARDS
) ? -1 : 1;
2290 ASSERT(txg
== 0 || !hole
);
2292 if (lvl
== dn
->dn_phys
->dn_nlevels
) {
2294 epb
= dn
->dn_phys
->dn_nblkptr
;
2295 data
= dn
->dn_phys
->dn_blkptr
;
2297 uint64_t blkid
= dbuf_whichblock(dn
, lvl
, *offset
);
2298 error
= dbuf_hold_impl(dn
, lvl
, blkid
, TRUE
, FALSE
, FTAG
, &db
);
2300 if (error
!= ENOENT
)
2305 * This can only happen when we are searching up
2306 * the block tree for data. We don't really need to
2307 * adjust the offset, as we will just end up looking
2308 * at the pointer to this block in its parent, and its
2309 * going to be unallocated, so we will skip over it.
2311 return (SET_ERROR(ESRCH
));
2313 error
= dbuf_read(db
, NULL
,
2314 DB_RF_CANFAIL
| DB_RF_HAVESTRUCT
| DB_RF_NO_DECRYPT
);
2316 dbuf_rele(db
, FTAG
);
2319 data
= db
->db
.db_data
;
2323 if (db
!= NULL
&& txg
!= 0 && (db
->db_blkptr
== NULL
||
2324 db
->db_blkptr
->blk_birth
<= txg
||
2325 BP_IS_HOLE(db
->db_blkptr
))) {
2327 * This can only happen when we are searching up the tree
2328 * and these conditions mean that we need to keep climbing.
2330 error
= SET_ERROR(ESRCH
);
2331 } else if (lvl
== 0) {
2332 dnode_phys_t
*dnp
= data
;
2334 ASSERT(dn
->dn_type
== DMU_OT_DNODE
);
2335 ASSERT(!(flags
& DNODE_FIND_BACKWARDS
));
2337 for (i
= (*offset
>> DNODE_SHIFT
) & (blkfill
- 1);
2338 i
< blkfill
; i
+= dnp
[i
].dn_extra_slots
+ 1) {
2339 if ((dnp
[i
].dn_type
== DMU_OT_NONE
) == hole
)
2344 error
= SET_ERROR(ESRCH
);
2346 *offset
= (*offset
& ~(DNODE_BLOCK_SIZE
- 1)) +
2349 blkptr_t
*bp
= data
;
2350 uint64_t start
= *offset
;
2351 span
= (lvl
- 1) * epbs
+ dn
->dn_datablkshift
;
2353 maxfill
= blkfill
<< ((lvl
- 1) * epbs
);
2360 if (span
>= 8 * sizeof (*offset
)) {
2361 /* This only happens on the highest indirection level */
2362 ASSERT3U((lvl
- 1), ==, dn
->dn_phys
->dn_nlevels
- 1);
2365 *offset
= *offset
>> span
;
2368 for (i
= BF64_GET(*offset
, 0, epbs
);
2369 i
>= 0 && i
< epb
; i
+= inc
) {
2370 if (BP_GET_FILL(&bp
[i
]) >= minfill
&&
2371 BP_GET_FILL(&bp
[i
]) <= maxfill
&&
2372 (hole
|| bp
[i
].blk_birth
> txg
))
2374 if (inc
> 0 || *offset
> 0)
2378 if (span
>= 8 * sizeof (*offset
)) {
2381 *offset
= *offset
<< span
;
2385 /* traversing backwards; position offset at the end */
2386 ASSERT3U(*offset
, <=, start
);
2387 *offset
= MIN(*offset
+ (1ULL << span
) - 1, start
);
2388 } else if (*offset
< start
) {
2391 if (i
< 0 || i
>= epb
)
2392 error
= SET_ERROR(ESRCH
);
2396 dbuf_rele(db
, FTAG
);
2402 * Find the next hole, data, or sparse region at or after *offset.
2403 * The value 'blkfill' tells us how many items we expect to find
2404 * in an L0 data block; this value is 1 for normal objects,
2405 * DNODES_PER_BLOCK for the meta dnode, and some fraction of
2406 * DNODES_PER_BLOCK when searching for sparse regions thereof.
2410 * dnode_next_offset(dn, flags, offset, 1, 1, 0);
2411 * Finds the next/previous hole/data in a file.
2412 * Used in dmu_offset_next().
2414 * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg);
2415 * Finds the next free/allocated dnode an objset's meta-dnode.
2416 * Only finds objects that have new contents since txg (ie.
2417 * bonus buffer changes and content removal are ignored).
2418 * Used in dmu_object_next().
2420 * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0);
2421 * Finds the next L2 meta-dnode bp that's at most 1/4 full.
2422 * Used in dmu_object_alloc().
2425 dnode_next_offset(dnode_t
*dn
, int flags
, uint64_t *offset
,
2426 int minlvl
, uint64_t blkfill
, uint64_t txg
)
2428 uint64_t initial_offset
= *offset
;
2432 if (!(flags
& DNODE_FIND_HAVELOCK
))
2433 rw_enter(&dn
->dn_struct_rwlock
, RW_READER
);
2435 if (dn
->dn_phys
->dn_nlevels
== 0) {
2436 error
= SET_ERROR(ESRCH
);
2440 if (dn
->dn_datablkshift
== 0) {
2441 if (*offset
< dn
->dn_datablksz
) {
2442 if (flags
& DNODE_FIND_HOLE
)
2443 *offset
= dn
->dn_datablksz
;
2445 error
= SET_ERROR(ESRCH
);
2450 maxlvl
= dn
->dn_phys
->dn_nlevels
;
2452 for (lvl
= minlvl
; lvl
<= maxlvl
; lvl
++) {
2453 error
= dnode_next_offset_level(dn
,
2454 flags
, offset
, lvl
, blkfill
, txg
);
2459 while (error
== 0 && --lvl
>= minlvl
) {
2460 error
= dnode_next_offset_level(dn
,
2461 flags
, offset
, lvl
, blkfill
, txg
);
2465 * There's always a "virtual hole" at the end of the object, even
2466 * if all BP's which physically exist are non-holes.
2468 if ((flags
& DNODE_FIND_HOLE
) && error
== ESRCH
&& txg
== 0 &&
2469 minlvl
== 1 && blkfill
== 1 && !(flags
& DNODE_FIND_BACKWARDS
)) {
2473 if (error
== 0 && (flags
& DNODE_FIND_BACKWARDS
?
2474 initial_offset
< *offset
: initial_offset
> *offset
))
2475 error
= SET_ERROR(ESRCH
);
2477 if (!(flags
& DNODE_FIND_HAVELOCK
))
2478 rw_exit(&dn
->dn_struct_rwlock
);