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 https://opensource.org/licenses/CDDL-1.0.
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, 2020 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_zfs.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_free_interior_lock_retry", KSTAT_DATA_UINT64 },
59 { "dnode_allocate", KSTAT_DATA_UINT64 },
60 { "dnode_reallocate", KSTAT_DATA_UINT64 },
61 { "dnode_buf_evict", KSTAT_DATA_UINT64 },
62 { "dnode_alloc_next_chunk", KSTAT_DATA_UINT64 },
63 { "dnode_alloc_race", KSTAT_DATA_UINT64 },
64 { "dnode_alloc_next_block", KSTAT_DATA_UINT64 },
65 { "dnode_move_invalid", KSTAT_DATA_UINT64 },
66 { "dnode_move_recheck1", KSTAT_DATA_UINT64 },
67 { "dnode_move_recheck2", KSTAT_DATA_UINT64 },
68 { "dnode_move_special", KSTAT_DATA_UINT64 },
69 { "dnode_move_handle", KSTAT_DATA_UINT64 },
70 { "dnode_move_rwlock", KSTAT_DATA_UINT64 },
71 { "dnode_move_active", KSTAT_DATA_UINT64 },
74 dnode_sums_t dnode_sums;
76 static kstat_t *dnode_ksp;
77 static kmem_cache_t *dnode_cache;
79 static dnode_phys_t dnode_phys_zero __maybe_unused;
81 int zfs_default_bs = SPA_MINBLOCKSHIFT;
82 int zfs_default_ibs = DN_MAX_INDBLKSHIFT;
85 static kmem_cbrc_t dnode_move(void *, void *, size_t, void *);
89 dbuf_compare(const void *x1, const void *x2)
91 const dmu_buf_impl_t *d1 = x1;
92 const dmu_buf_impl_t *d2 = x2;
94 int cmp = TREE_CMP(d1->db_level, d2->db_level);
98 cmp = TREE_CMP(d1->db_blkid, d2->db_blkid);
102 if (d1->db_state == DB_SEARCH) {
103 ASSERT3S(d2->db_state, !=, DB_SEARCH);
105 } else if (d2->db_state == DB_SEARCH) {
106 ASSERT3S(d1->db_state, !=, DB_SEARCH);
110 return (TREE_PCMP(d1, d2));
114 dnode_cons(void *arg, void *unused, int kmflag)
116 (void) unused, (void) 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);
123 cv_init(&dn->dn_nodnholds, NULL, CV_DEFAULT, NULL);
126 * Every dbuf has a reference, and dropping a tracked reference is
127 * O(number of references), so don't track dn_holds.
129 zfs_refcount_create_untracked(&dn->dn_holds);
130 zfs_refcount_create(&dn->dn_tx_holds);
131 list_link_init(&dn->dn_link);
133 memset(dn->dn_next_type, 0, sizeof (dn->dn_next_type));
134 memset(dn->dn_next_nblkptr, 0, sizeof (dn->dn_next_nblkptr));
135 memset(dn->dn_next_nlevels, 0, sizeof (dn->dn_next_nlevels));
136 memset(dn->dn_next_indblkshift, 0, sizeof (dn->dn_next_indblkshift));
137 memset(dn->dn_next_bonustype, 0, sizeof (dn->dn_next_bonustype));
138 memset(dn->dn_rm_spillblk, 0, sizeof (dn->dn_rm_spillblk));
139 memset(dn->dn_next_bonuslen, 0, sizeof (dn->dn_next_bonuslen));
140 memset(dn->dn_next_blksz, 0, sizeof (dn->dn_next_blksz));
141 memset(dn->dn_next_maxblkid, 0, sizeof (dn->dn_next_maxblkid));
143 for (int i = 0; i < TXG_SIZE; i++) {
144 multilist_link_init(&dn->dn_dirty_link[i]);
145 dn->dn_free_ranges[i] = NULL;
146 list_create(&dn->dn_dirty_records[i],
147 sizeof (dbuf_dirty_record_t),
148 offsetof(dbuf_dirty_record_t, dr_dirty_node));
151 dn->dn_allocated_txg = 0;
153 dn->dn_assigned_txg = 0;
154 dn->dn_dirty_txg = 0;
156 dn->dn_dirtyctx_firstset = NULL;
158 dn->dn_have_spill = B_FALSE;
164 dn->dn_oldprojid = ZFS_DEFAULT_PROJID;
167 dn->dn_newprojid = ZFS_DEFAULT_PROJID;
170 dn->dn_dbufs_count = 0;
171 avl_create(&dn->dn_dbufs, dbuf_compare, sizeof (dmu_buf_impl_t),
172 offsetof(dmu_buf_impl_t, db_link));
179 dnode_dest(void *arg, void *unused)
184 rw_destroy(&dn->dn_struct_rwlock);
185 mutex_destroy(&dn->dn_mtx);
186 mutex_destroy(&dn->dn_dbufs_mtx);
187 cv_destroy(&dn->dn_notxholds);
188 cv_destroy(&dn->dn_nodnholds);
189 zfs_refcount_destroy(&dn->dn_holds);
190 zfs_refcount_destroy(&dn->dn_tx_holds);
191 ASSERT(!list_link_active(&dn->dn_link));
193 for (int i = 0; i < TXG_SIZE; i++) {
194 ASSERT(!multilist_link_active(&dn->dn_dirty_link[i]));
195 ASSERT3P(dn->dn_free_ranges[i], ==, NULL);
196 list_destroy(&dn->dn_dirty_records[i]);
197 ASSERT0(dn->dn_next_nblkptr[i]);
198 ASSERT0(dn->dn_next_nlevels[i]);
199 ASSERT0(dn->dn_next_indblkshift[i]);
200 ASSERT0(dn->dn_next_bonustype[i]);
201 ASSERT0(dn->dn_rm_spillblk[i]);
202 ASSERT0(dn->dn_next_bonuslen[i]);
203 ASSERT0(dn->dn_next_blksz[i]);
204 ASSERT0(dn->dn_next_maxblkid[i]);
207 ASSERT0(dn->dn_allocated_txg);
208 ASSERT0(dn->dn_free_txg);
209 ASSERT0(dn->dn_assigned_txg);
210 ASSERT0(dn->dn_dirty_txg);
211 ASSERT0(dn->dn_dirtyctx);
212 ASSERT3P(dn->dn_dirtyctx_firstset, ==, NULL);
213 ASSERT3P(dn->dn_bonus, ==, NULL);
214 ASSERT(!dn->dn_have_spill);
215 ASSERT3P(dn->dn_zio, ==, NULL);
216 ASSERT0(dn->dn_oldused);
217 ASSERT0(dn->dn_oldflags);
218 ASSERT0(dn->dn_olduid);
219 ASSERT0(dn->dn_oldgid);
220 ASSERT0(dn->dn_oldprojid);
221 ASSERT0(dn->dn_newuid);
222 ASSERT0(dn->dn_newgid);
223 ASSERT0(dn->dn_newprojid);
224 ASSERT0(dn->dn_id_flags);
226 ASSERT0(dn->dn_dbufs_count);
227 avl_destroy(&dn->dn_dbufs);
231 dnode_kstats_update(kstat_t *ksp, int rw)
233 dnode_stats_t *ds = ksp->ks_data;
235 if (rw == KSTAT_WRITE)
237 ds->dnode_hold_dbuf_hold.value.ui64 =
238 wmsum_value(&dnode_sums.dnode_hold_dbuf_hold);
239 ds->dnode_hold_dbuf_read.value.ui64 =
240 wmsum_value(&dnode_sums.dnode_hold_dbuf_read);
241 ds->dnode_hold_alloc_hits.value.ui64 =
242 wmsum_value(&dnode_sums.dnode_hold_alloc_hits);
243 ds->dnode_hold_alloc_misses.value.ui64 =
244 wmsum_value(&dnode_sums.dnode_hold_alloc_misses);
245 ds->dnode_hold_alloc_interior.value.ui64 =
246 wmsum_value(&dnode_sums.dnode_hold_alloc_interior);
247 ds->dnode_hold_alloc_lock_retry.value.ui64 =
248 wmsum_value(&dnode_sums.dnode_hold_alloc_lock_retry);
249 ds->dnode_hold_alloc_lock_misses.value.ui64 =
250 wmsum_value(&dnode_sums.dnode_hold_alloc_lock_misses);
251 ds->dnode_hold_alloc_type_none.value.ui64 =
252 wmsum_value(&dnode_sums.dnode_hold_alloc_type_none);
253 ds->dnode_hold_free_hits.value.ui64 =
254 wmsum_value(&dnode_sums.dnode_hold_free_hits);
255 ds->dnode_hold_free_misses.value.ui64 =
256 wmsum_value(&dnode_sums.dnode_hold_free_misses);
257 ds->dnode_hold_free_lock_misses.value.ui64 =
258 wmsum_value(&dnode_sums.dnode_hold_free_lock_misses);
259 ds->dnode_hold_free_lock_retry.value.ui64 =
260 wmsum_value(&dnode_sums.dnode_hold_free_lock_retry);
261 ds->dnode_hold_free_refcount.value.ui64 =
262 wmsum_value(&dnode_sums.dnode_hold_free_refcount);
263 ds->dnode_hold_free_overflow.value.ui64 =
264 wmsum_value(&dnode_sums.dnode_hold_free_overflow);
265 ds->dnode_free_interior_lock_retry.value.ui64 =
266 wmsum_value(&dnode_sums.dnode_free_interior_lock_retry);
267 ds->dnode_allocate.value.ui64 =
268 wmsum_value(&dnode_sums.dnode_allocate);
269 ds->dnode_reallocate.value.ui64 =
270 wmsum_value(&dnode_sums.dnode_reallocate);
271 ds->dnode_buf_evict.value.ui64 =
272 wmsum_value(&dnode_sums.dnode_buf_evict);
273 ds->dnode_alloc_next_chunk.value.ui64 =
274 wmsum_value(&dnode_sums.dnode_alloc_next_chunk);
275 ds->dnode_alloc_race.value.ui64 =
276 wmsum_value(&dnode_sums.dnode_alloc_race);
277 ds->dnode_alloc_next_block.value.ui64 =
278 wmsum_value(&dnode_sums.dnode_alloc_next_block);
279 ds->dnode_move_invalid.value.ui64 =
280 wmsum_value(&dnode_sums.dnode_move_invalid);
281 ds->dnode_move_recheck1.value.ui64 =
282 wmsum_value(&dnode_sums.dnode_move_recheck1);
283 ds->dnode_move_recheck2.value.ui64 =
284 wmsum_value(&dnode_sums.dnode_move_recheck2);
285 ds->dnode_move_special.value.ui64 =
286 wmsum_value(&dnode_sums.dnode_move_special);
287 ds->dnode_move_handle.value.ui64 =
288 wmsum_value(&dnode_sums.dnode_move_handle);
289 ds->dnode_move_rwlock.value.ui64 =
290 wmsum_value(&dnode_sums.dnode_move_rwlock);
291 ds->dnode_move_active.value.ui64 =
292 wmsum_value(&dnode_sums.dnode_move_active);
299 ASSERT(dnode_cache == NULL);
300 dnode_cache = kmem_cache_create("dnode_t", sizeof (dnode_t),
301 0, dnode_cons, dnode_dest, NULL, NULL, NULL, 0);
302 kmem_cache_set_move(dnode_cache, dnode_move);
304 wmsum_init(&dnode_sums.dnode_hold_dbuf_hold, 0);
305 wmsum_init(&dnode_sums.dnode_hold_dbuf_read, 0);
306 wmsum_init(&dnode_sums.dnode_hold_alloc_hits, 0);
307 wmsum_init(&dnode_sums.dnode_hold_alloc_misses, 0);
308 wmsum_init(&dnode_sums.dnode_hold_alloc_interior, 0);
309 wmsum_init(&dnode_sums.dnode_hold_alloc_lock_retry, 0);
310 wmsum_init(&dnode_sums.dnode_hold_alloc_lock_misses, 0);
311 wmsum_init(&dnode_sums.dnode_hold_alloc_type_none, 0);
312 wmsum_init(&dnode_sums.dnode_hold_free_hits, 0);
313 wmsum_init(&dnode_sums.dnode_hold_free_misses, 0);
314 wmsum_init(&dnode_sums.dnode_hold_free_lock_misses, 0);
315 wmsum_init(&dnode_sums.dnode_hold_free_lock_retry, 0);
316 wmsum_init(&dnode_sums.dnode_hold_free_refcount, 0);
317 wmsum_init(&dnode_sums.dnode_hold_free_overflow, 0);
318 wmsum_init(&dnode_sums.dnode_free_interior_lock_retry, 0);
319 wmsum_init(&dnode_sums.dnode_allocate, 0);
320 wmsum_init(&dnode_sums.dnode_reallocate, 0);
321 wmsum_init(&dnode_sums.dnode_buf_evict, 0);
322 wmsum_init(&dnode_sums.dnode_alloc_next_chunk, 0);
323 wmsum_init(&dnode_sums.dnode_alloc_race, 0);
324 wmsum_init(&dnode_sums.dnode_alloc_next_block, 0);
325 wmsum_init(&dnode_sums.dnode_move_invalid, 0);
326 wmsum_init(&dnode_sums.dnode_move_recheck1, 0);
327 wmsum_init(&dnode_sums.dnode_move_recheck2, 0);
328 wmsum_init(&dnode_sums.dnode_move_special, 0);
329 wmsum_init(&dnode_sums.dnode_move_handle, 0);
330 wmsum_init(&dnode_sums.dnode_move_rwlock, 0);
331 wmsum_init(&dnode_sums.dnode_move_active, 0);
333 dnode_ksp = kstat_create("zfs", 0, "dnodestats", "misc",
334 KSTAT_TYPE_NAMED, sizeof (dnode_stats) / sizeof (kstat_named_t),
336 if (dnode_ksp != NULL) {
337 dnode_ksp->ks_data = &dnode_stats;
338 dnode_ksp->ks_update = dnode_kstats_update;
339 kstat_install(dnode_ksp);
346 if (dnode_ksp != NULL) {
347 kstat_delete(dnode_ksp);
351 wmsum_fini(&dnode_sums.dnode_hold_dbuf_hold);
352 wmsum_fini(&dnode_sums.dnode_hold_dbuf_read);
353 wmsum_fini(&dnode_sums.dnode_hold_alloc_hits);
354 wmsum_fini(&dnode_sums.dnode_hold_alloc_misses);
355 wmsum_fini(&dnode_sums.dnode_hold_alloc_interior);
356 wmsum_fini(&dnode_sums.dnode_hold_alloc_lock_retry);
357 wmsum_fini(&dnode_sums.dnode_hold_alloc_lock_misses);
358 wmsum_fini(&dnode_sums.dnode_hold_alloc_type_none);
359 wmsum_fini(&dnode_sums.dnode_hold_free_hits);
360 wmsum_fini(&dnode_sums.dnode_hold_free_misses);
361 wmsum_fini(&dnode_sums.dnode_hold_free_lock_misses);
362 wmsum_fini(&dnode_sums.dnode_hold_free_lock_retry);
363 wmsum_fini(&dnode_sums.dnode_hold_free_refcount);
364 wmsum_fini(&dnode_sums.dnode_hold_free_overflow);
365 wmsum_fini(&dnode_sums.dnode_free_interior_lock_retry);
366 wmsum_fini(&dnode_sums.dnode_allocate);
367 wmsum_fini(&dnode_sums.dnode_reallocate);
368 wmsum_fini(&dnode_sums.dnode_buf_evict);
369 wmsum_fini(&dnode_sums.dnode_alloc_next_chunk);
370 wmsum_fini(&dnode_sums.dnode_alloc_race);
371 wmsum_fini(&dnode_sums.dnode_alloc_next_block);
372 wmsum_fini(&dnode_sums.dnode_move_invalid);
373 wmsum_fini(&dnode_sums.dnode_move_recheck1);
374 wmsum_fini(&dnode_sums.dnode_move_recheck2);
375 wmsum_fini(&dnode_sums.dnode_move_special);
376 wmsum_fini(&dnode_sums.dnode_move_handle);
377 wmsum_fini(&dnode_sums.dnode_move_rwlock);
378 wmsum_fini(&dnode_sums.dnode_move_active);
380 kmem_cache_destroy(dnode_cache);
387 dnode_verify(dnode_t *dn)
389 int drop_struct_lock = FALSE;
392 ASSERT(dn->dn_objset);
393 ASSERT(dn->dn_handle->dnh_dnode == dn);
395 ASSERT(DMU_OT_IS_VALID(dn->dn_phys->dn_type));
397 if (!(zfs_flags & ZFS_DEBUG_DNODE_VERIFY))
400 if (!RW_WRITE_HELD(&dn->dn_struct_rwlock)) {
401 rw_enter(&dn->dn_struct_rwlock, RW_READER);
402 drop_struct_lock = TRUE;
404 if (dn->dn_phys->dn_type != DMU_OT_NONE || dn->dn_allocated_txg != 0) {
406 int max_bonuslen = DN_SLOTS_TO_BONUSLEN(dn->dn_num_slots);
407 ASSERT3U(dn->dn_indblkshift, <=, SPA_MAXBLOCKSHIFT);
408 if (dn->dn_datablkshift) {
409 ASSERT3U(dn->dn_datablkshift, >=, SPA_MINBLOCKSHIFT);
410 ASSERT3U(dn->dn_datablkshift, <=, SPA_MAXBLOCKSHIFT);
411 ASSERT3U(1<<dn->dn_datablkshift, ==, dn->dn_datablksz);
413 ASSERT3U(dn->dn_nlevels, <=, 30);
414 ASSERT(DMU_OT_IS_VALID(dn->dn_type));
415 ASSERT3U(dn->dn_nblkptr, >=, 1);
416 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR);
417 ASSERT3U(dn->dn_bonuslen, <=, max_bonuslen);
418 ASSERT3U(dn->dn_datablksz, ==,
419 dn->dn_datablkszsec << SPA_MINBLOCKSHIFT);
420 ASSERT3U(ISP2(dn->dn_datablksz), ==, dn->dn_datablkshift != 0);
421 ASSERT3U((dn->dn_nblkptr - 1) * sizeof (blkptr_t) +
422 dn->dn_bonuslen, <=, max_bonuslen);
423 for (i = 0; i < TXG_SIZE; i++) {
424 ASSERT3U(dn->dn_next_nlevels[i], <=, dn->dn_nlevels);
427 if (dn->dn_phys->dn_type != DMU_OT_NONE)
428 ASSERT3U(dn->dn_phys->dn_nlevels, <=, dn->dn_nlevels);
429 ASSERT(DMU_OBJECT_IS_SPECIAL(dn->dn_object) || dn->dn_dbuf != NULL);
430 if (dn->dn_dbuf != NULL) {
431 ASSERT3P(dn->dn_phys, ==,
432 (dnode_phys_t *)dn->dn_dbuf->db.db_data +
433 (dn->dn_object % (dn->dn_dbuf->db.db_size >> DNODE_SHIFT)));
435 if (drop_struct_lock)
436 rw_exit(&dn->dn_struct_rwlock);
441 dnode_byteswap(dnode_phys_t *dnp)
443 uint64_t *buf64 = (void*)&dnp->dn_blkptr;
446 if (dnp->dn_type == DMU_OT_NONE) {
447 memset(dnp, 0, sizeof (dnode_phys_t));
451 dnp->dn_datablkszsec = BSWAP_16(dnp->dn_datablkszsec);
452 dnp->dn_bonuslen = BSWAP_16(dnp->dn_bonuslen);
453 dnp->dn_extra_slots = BSWAP_8(dnp->dn_extra_slots);
454 dnp->dn_maxblkid = BSWAP_64(dnp->dn_maxblkid);
455 dnp->dn_used = BSWAP_64(dnp->dn_used);
458 * dn_nblkptr is only one byte, so it's OK to read it in either
459 * byte order. We can't read dn_bouslen.
461 ASSERT(dnp->dn_indblkshift <= SPA_MAXBLOCKSHIFT);
462 ASSERT(dnp->dn_nblkptr <= DN_MAX_NBLKPTR);
463 for (i = 0; i < dnp->dn_nblkptr * sizeof (blkptr_t)/8; i++)
464 buf64[i] = BSWAP_64(buf64[i]);
467 * OK to check dn_bonuslen for zero, because it won't matter if
468 * we have the wrong byte order. This is necessary because the
469 * dnode dnode is smaller than a regular dnode.
471 if (dnp->dn_bonuslen != 0) {
472 dmu_object_byteswap_t byteswap;
473 ASSERT(DMU_OT_IS_VALID(dnp->dn_bonustype));
474 byteswap = DMU_OT_BYTESWAP(dnp->dn_bonustype);
475 dmu_ot_byteswap[byteswap].ob_func(DN_BONUS(dnp),
476 DN_MAX_BONUS_LEN(dnp));
479 /* Swap SPILL block if we have one */
480 if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR)
481 byteswap_uint64_array(DN_SPILL_BLKPTR(dnp), sizeof (blkptr_t));
485 dnode_buf_byteswap(void *vbuf, size_t size)
489 ASSERT3U(sizeof (dnode_phys_t), ==, (1<<DNODE_SHIFT));
490 ASSERT((size & (sizeof (dnode_phys_t)-1)) == 0);
493 dnode_phys_t *dnp = (void *)(((char *)vbuf) + i);
497 if (dnp->dn_type != DMU_OT_NONE)
498 i += dnp->dn_extra_slots * DNODE_MIN_SIZE;
503 dnode_setbonuslen(dnode_t *dn, int newsize, dmu_tx_t *tx)
505 ASSERT3U(zfs_refcount_count(&dn->dn_holds), >=, 1);
507 dnode_setdirty(dn, tx);
508 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
509 ASSERT3U(newsize, <=, DN_SLOTS_TO_BONUSLEN(dn->dn_num_slots) -
510 (dn->dn_nblkptr-1) * sizeof (blkptr_t));
512 if (newsize < dn->dn_bonuslen) {
513 /* clear any data after the end of the new size */
514 size_t diff = dn->dn_bonuslen - newsize;
515 char *data_end = ((char *)dn->dn_bonus->db.db_data) + newsize;
516 memset(data_end, 0, diff);
519 dn->dn_bonuslen = newsize;
521 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = DN_ZERO_BONUSLEN;
523 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen;
524 rw_exit(&dn->dn_struct_rwlock);
528 dnode_setbonus_type(dnode_t *dn, dmu_object_type_t newtype, dmu_tx_t *tx)
530 ASSERT3U(zfs_refcount_count(&dn->dn_holds), >=, 1);
531 dnode_setdirty(dn, tx);
532 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
533 dn->dn_bonustype = newtype;
534 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype;
535 rw_exit(&dn->dn_struct_rwlock);
539 dnode_rm_spill(dnode_t *dn, dmu_tx_t *tx)
541 ASSERT3U(zfs_refcount_count(&dn->dn_holds), >=, 1);
542 ASSERT(RW_WRITE_HELD(&dn->dn_struct_rwlock));
543 dnode_setdirty(dn, tx);
544 dn->dn_rm_spillblk[tx->tx_txg & TXG_MASK] = DN_KILL_SPILLBLK;
545 dn->dn_have_spill = B_FALSE;
549 dnode_setdblksz(dnode_t *dn, int size)
551 ASSERT0(P2PHASE(size, SPA_MINBLOCKSIZE));
552 ASSERT3U(size, <=, SPA_MAXBLOCKSIZE);
553 ASSERT3U(size, >=, SPA_MINBLOCKSIZE);
554 ASSERT3U(size >> SPA_MINBLOCKSHIFT, <,
555 1<<(sizeof (dn->dn_phys->dn_datablkszsec) * 8));
556 dn->dn_datablksz = size;
557 dn->dn_datablkszsec = size >> SPA_MINBLOCKSHIFT;
558 dn->dn_datablkshift = ISP2(size) ? highbit64(size - 1) : 0;
562 dnode_create(objset_t *os, dnode_phys_t *dnp, dmu_buf_impl_t *db,
563 uint64_t object, dnode_handle_t *dnh)
567 dn = kmem_cache_alloc(dnode_cache, KM_SLEEP);
571 * Defer setting dn_objset until the dnode is ready to be a candidate
572 * for the dnode_move() callback.
574 dn->dn_object = object;
579 if (dnp->dn_datablkszsec) {
580 dnode_setdblksz(dn, dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT);
582 dn->dn_datablksz = 0;
583 dn->dn_datablkszsec = 0;
584 dn->dn_datablkshift = 0;
586 dn->dn_indblkshift = dnp->dn_indblkshift;
587 dn->dn_nlevels = dnp->dn_nlevels;
588 dn->dn_type = dnp->dn_type;
589 dn->dn_nblkptr = dnp->dn_nblkptr;
590 dn->dn_checksum = dnp->dn_checksum;
591 dn->dn_compress = dnp->dn_compress;
592 dn->dn_bonustype = dnp->dn_bonustype;
593 dn->dn_bonuslen = dnp->dn_bonuslen;
594 dn->dn_num_slots = dnp->dn_extra_slots + 1;
595 dn->dn_maxblkid = dnp->dn_maxblkid;
596 dn->dn_have_spill = ((dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) != 0);
599 dmu_zfetch_init(&dn->dn_zfetch, dn);
601 ASSERT(DMU_OT_IS_VALID(dn->dn_phys->dn_type));
602 ASSERT(zrl_is_locked(&dnh->dnh_zrlock));
603 ASSERT(!DN_SLOT_IS_PTR(dnh->dnh_dnode));
605 mutex_enter(&os->os_lock);
608 * Exclude special dnodes from os_dnodes so an empty os_dnodes
609 * signifies that the special dnodes have no references from
610 * their children (the entries in os_dnodes). This allows
611 * dnode_destroy() to easily determine if the last child has
612 * been removed and then complete eviction of the objset.
614 if (!DMU_OBJECT_IS_SPECIAL(object))
615 list_insert_head(&os->os_dnodes, dn);
619 * Everything else must be valid before assigning dn_objset
620 * makes the dnode eligible for dnode_move().
625 mutex_exit(&os->os_lock);
627 arc_space_consume(sizeof (dnode_t), ARC_SPACE_DNODE);
633 * Caller must be holding the dnode handle, which is released upon return.
636 dnode_destroy(dnode_t *dn)
638 objset_t *os = dn->dn_objset;
639 boolean_t complete_os_eviction = B_FALSE;
641 ASSERT((dn->dn_id_flags & DN_ID_NEW_EXIST) == 0);
643 mutex_enter(&os->os_lock);
644 POINTER_INVALIDATE(&dn->dn_objset);
645 if (!DMU_OBJECT_IS_SPECIAL(dn->dn_object)) {
646 list_remove(&os->os_dnodes, dn);
647 complete_os_eviction =
648 list_is_empty(&os->os_dnodes) &&
649 list_link_active(&os->os_evicting_node);
651 mutex_exit(&os->os_lock);
653 /* the dnode can no longer move, so we can release the handle */
654 if (!zrl_is_locked(&dn->dn_handle->dnh_zrlock))
655 zrl_remove(&dn->dn_handle->dnh_zrlock);
657 dn->dn_allocated_txg = 0;
659 dn->dn_assigned_txg = 0;
660 dn->dn_dirty_txg = 0;
663 dn->dn_dirtyctx_firstset = NULL;
664 if (dn->dn_bonus != NULL) {
665 mutex_enter(&dn->dn_bonus->db_mtx);
666 dbuf_destroy(dn->dn_bonus);
671 dn->dn_have_spill = B_FALSE;
676 dn->dn_oldprojid = ZFS_DEFAULT_PROJID;
679 dn->dn_newprojid = ZFS_DEFAULT_PROJID;
682 dmu_zfetch_fini(&dn->dn_zfetch);
683 kmem_cache_free(dnode_cache, dn);
684 arc_space_return(sizeof (dnode_t), ARC_SPACE_DNODE);
686 if (complete_os_eviction)
687 dmu_objset_evict_done(os);
691 dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs,
692 dmu_object_type_t bonustype, int bonuslen, int dn_slots, dmu_tx_t *tx)
696 ASSERT3U(dn_slots, >, 0);
697 ASSERT3U(dn_slots << DNODE_SHIFT, <=,
698 spa_maxdnodesize(dmu_objset_spa(dn->dn_objset)));
699 ASSERT3U(blocksize, <=,
700 spa_maxblocksize(dmu_objset_spa(dn->dn_objset)));
702 blocksize = 1 << zfs_default_bs;
704 blocksize = P2ROUNDUP(blocksize, SPA_MINBLOCKSIZE);
707 ibs = zfs_default_ibs;
709 ibs = MIN(MAX(ibs, DN_MIN_INDBLKSHIFT), DN_MAX_INDBLKSHIFT);
711 dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d dn_slots=%d\n",
712 dn->dn_objset, (u_longlong_t)dn->dn_object,
713 (u_longlong_t)tx->tx_txg, blocksize, ibs, dn_slots);
714 DNODE_STAT_BUMP(dnode_allocate);
716 ASSERT(dn->dn_type == DMU_OT_NONE);
717 ASSERT0(memcmp(dn->dn_phys, &dnode_phys_zero, sizeof (dnode_phys_t)));
718 ASSERT(dn->dn_phys->dn_type == DMU_OT_NONE);
719 ASSERT(ot != DMU_OT_NONE);
720 ASSERT(DMU_OT_IS_VALID(ot));
721 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) ||
722 (bonustype == DMU_OT_SA && bonuslen == 0) ||
723 (bonustype == DMU_OTN_UINT64_METADATA && bonuslen == 0) ||
724 (bonustype != DMU_OT_NONE && bonuslen != 0));
725 ASSERT(DMU_OT_IS_VALID(bonustype));
726 ASSERT3U(bonuslen, <=, DN_SLOTS_TO_BONUSLEN(dn_slots));
727 ASSERT(dn->dn_type == DMU_OT_NONE);
728 ASSERT0(dn->dn_maxblkid);
729 ASSERT0(dn->dn_allocated_txg);
730 ASSERT0(dn->dn_assigned_txg);
731 ASSERT(zfs_refcount_is_zero(&dn->dn_tx_holds));
732 ASSERT3U(zfs_refcount_count(&dn->dn_holds), <=, 1);
733 ASSERT(avl_is_empty(&dn->dn_dbufs));
735 for (i = 0; i < TXG_SIZE; i++) {
736 ASSERT0(dn->dn_next_nblkptr[i]);
737 ASSERT0(dn->dn_next_nlevels[i]);
738 ASSERT0(dn->dn_next_indblkshift[i]);
739 ASSERT0(dn->dn_next_bonuslen[i]);
740 ASSERT0(dn->dn_next_bonustype[i]);
741 ASSERT0(dn->dn_rm_spillblk[i]);
742 ASSERT0(dn->dn_next_blksz[i]);
743 ASSERT0(dn->dn_next_maxblkid[i]);
744 ASSERT(!multilist_link_active(&dn->dn_dirty_link[i]));
745 ASSERT3P(list_head(&dn->dn_dirty_records[i]), ==, NULL);
746 ASSERT3P(dn->dn_free_ranges[i], ==, NULL);
750 dnode_setdblksz(dn, blocksize);
751 dn->dn_indblkshift = ibs;
753 dn->dn_num_slots = dn_slots;
754 if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */
757 dn->dn_nblkptr = MIN(DN_MAX_NBLKPTR,
758 1 + ((DN_SLOTS_TO_BONUSLEN(dn_slots) - bonuslen) >>
762 dn->dn_bonustype = bonustype;
763 dn->dn_bonuslen = bonuslen;
764 dn->dn_checksum = ZIO_CHECKSUM_INHERIT;
765 dn->dn_compress = ZIO_COMPRESS_INHERIT;
769 dn->dn_dirtyctx_firstset = NULL;
770 dn->dn_dirty_txg = 0;
772 dn->dn_allocated_txg = tx->tx_txg;
775 dnode_setdirty(dn, tx);
776 dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs;
777 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen;
778 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype;
779 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = dn->dn_datablksz;
783 dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize,
784 dmu_object_type_t bonustype, int bonuslen, int dn_slots,
785 boolean_t keep_spill, dmu_tx_t *tx)
789 ASSERT3U(blocksize, >=, SPA_MINBLOCKSIZE);
790 ASSERT3U(blocksize, <=,
791 spa_maxblocksize(dmu_objset_spa(dn->dn_objset)));
792 ASSERT0(blocksize % SPA_MINBLOCKSIZE);
793 ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT || dmu_tx_private_ok(tx));
794 ASSERT(tx->tx_txg != 0);
795 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) ||
796 (bonustype != DMU_OT_NONE && bonuslen != 0) ||
797 (bonustype == DMU_OT_SA && bonuslen == 0));
798 ASSERT(DMU_OT_IS_VALID(bonustype));
799 ASSERT3U(bonuslen, <=,
800 DN_BONUS_SIZE(spa_maxdnodesize(dmu_objset_spa(dn->dn_objset))));
801 ASSERT3U(bonuslen, <=, DN_BONUS_SIZE(dn_slots << DNODE_SHIFT));
803 dnode_free_interior_slots(dn);
804 DNODE_STAT_BUMP(dnode_reallocate);
806 /* clean up any unreferenced dbufs */
807 dnode_evict_dbufs(dn);
811 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
812 dnode_setdirty(dn, tx);
813 if (dn->dn_datablksz != blocksize) {
814 /* change blocksize */
815 ASSERT0(dn->dn_maxblkid);
816 ASSERT(BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) ||
817 dnode_block_freed(dn, 0));
819 dnode_setdblksz(dn, blocksize);
820 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = blocksize;
822 if (dn->dn_bonuslen != bonuslen)
823 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = bonuslen;
825 if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */
828 nblkptr = MIN(DN_MAX_NBLKPTR,
829 1 + ((DN_SLOTS_TO_BONUSLEN(dn_slots) - bonuslen) >>
831 if (dn->dn_bonustype != bonustype)
832 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = bonustype;
833 if (dn->dn_nblkptr != nblkptr)
834 dn->dn_next_nblkptr[tx->tx_txg & TXG_MASK] = nblkptr;
835 if (dn->dn_phys->dn_flags & DNODE_FLAG_SPILL_BLKPTR && !keep_spill) {
836 dbuf_rm_spill(dn, tx);
837 dnode_rm_spill(dn, tx);
840 rw_exit(&dn->dn_struct_rwlock);
845 /* change bonus size and type */
846 mutex_enter(&dn->dn_mtx);
847 dn->dn_bonustype = bonustype;
848 dn->dn_bonuslen = bonuslen;
849 dn->dn_num_slots = dn_slots;
850 dn->dn_nblkptr = nblkptr;
851 dn->dn_checksum = ZIO_CHECKSUM_INHERIT;
852 dn->dn_compress = ZIO_COMPRESS_INHERIT;
853 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR);
855 /* fix up the bonus db_size */
857 dn->dn_bonus->db.db_size =
858 DN_SLOTS_TO_BONUSLEN(dn->dn_num_slots) -
859 (dn->dn_nblkptr-1) * sizeof (blkptr_t);
860 ASSERT(dn->dn_bonuslen <= dn->dn_bonus->db.db_size);
863 dn->dn_allocated_txg = tx->tx_txg;
864 mutex_exit(&dn->dn_mtx);
869 dnode_move_impl(dnode_t *odn, dnode_t *ndn)
871 ASSERT(!RW_LOCK_HELD(&odn->dn_struct_rwlock));
872 ASSERT(MUTEX_NOT_HELD(&odn->dn_mtx));
873 ASSERT(MUTEX_NOT_HELD(&odn->dn_dbufs_mtx));
876 ndn->dn_objset = odn->dn_objset;
877 ndn->dn_object = odn->dn_object;
878 ndn->dn_dbuf = odn->dn_dbuf;
879 ndn->dn_handle = odn->dn_handle;
880 ndn->dn_phys = odn->dn_phys;
881 ndn->dn_type = odn->dn_type;
882 ndn->dn_bonuslen = odn->dn_bonuslen;
883 ndn->dn_bonustype = odn->dn_bonustype;
884 ndn->dn_nblkptr = odn->dn_nblkptr;
885 ndn->dn_checksum = odn->dn_checksum;
886 ndn->dn_compress = odn->dn_compress;
887 ndn->dn_nlevels = odn->dn_nlevels;
888 ndn->dn_indblkshift = odn->dn_indblkshift;
889 ndn->dn_datablkshift = odn->dn_datablkshift;
890 ndn->dn_datablkszsec = odn->dn_datablkszsec;
891 ndn->dn_datablksz = odn->dn_datablksz;
892 ndn->dn_maxblkid = odn->dn_maxblkid;
893 ndn->dn_num_slots = odn->dn_num_slots;
894 memcpy(ndn->dn_next_type, odn->dn_next_type,
895 sizeof (odn->dn_next_type));
896 memcpy(ndn->dn_next_nblkptr, odn->dn_next_nblkptr,
897 sizeof (odn->dn_next_nblkptr));
898 memcpy(ndn->dn_next_nlevels, odn->dn_next_nlevels,
899 sizeof (odn->dn_next_nlevels));
900 memcpy(ndn->dn_next_indblkshift, odn->dn_next_indblkshift,
901 sizeof (odn->dn_next_indblkshift));
902 memcpy(ndn->dn_next_bonustype, odn->dn_next_bonustype,
903 sizeof (odn->dn_next_bonustype));
904 memcpy(ndn->dn_rm_spillblk, odn->dn_rm_spillblk,
905 sizeof (odn->dn_rm_spillblk));
906 memcpy(ndn->dn_next_bonuslen, odn->dn_next_bonuslen,
907 sizeof (odn->dn_next_bonuslen));
908 memcpy(ndn->dn_next_blksz, odn->dn_next_blksz,
909 sizeof (odn->dn_next_blksz));
910 memcpy(ndn->dn_next_maxblkid, odn->dn_next_maxblkid,
911 sizeof (odn->dn_next_maxblkid));
912 for (int i = 0; i < TXG_SIZE; i++) {
913 list_move_tail(&ndn->dn_dirty_records[i],
914 &odn->dn_dirty_records[i]);
916 memcpy(ndn->dn_free_ranges, odn->dn_free_ranges,
917 sizeof (odn->dn_free_ranges));
918 ndn->dn_allocated_txg = odn->dn_allocated_txg;
919 ndn->dn_free_txg = odn->dn_free_txg;
920 ndn->dn_assigned_txg = odn->dn_assigned_txg;
921 ndn->dn_dirty_txg = odn->dn_dirty_txg;
922 ndn->dn_dirtyctx = odn->dn_dirtyctx;
923 ndn->dn_dirtyctx_firstset = odn->dn_dirtyctx_firstset;
924 ASSERT(zfs_refcount_count(&odn->dn_tx_holds) == 0);
925 zfs_refcount_transfer(&ndn->dn_holds, &odn->dn_holds);
926 ASSERT(avl_is_empty(&ndn->dn_dbufs));
927 avl_swap(&ndn->dn_dbufs, &odn->dn_dbufs);
928 ndn->dn_dbufs_count = odn->dn_dbufs_count;
929 ndn->dn_bonus = odn->dn_bonus;
930 ndn->dn_have_spill = odn->dn_have_spill;
931 ndn->dn_zio = odn->dn_zio;
932 ndn->dn_oldused = odn->dn_oldused;
933 ndn->dn_oldflags = odn->dn_oldflags;
934 ndn->dn_olduid = odn->dn_olduid;
935 ndn->dn_oldgid = odn->dn_oldgid;
936 ndn->dn_oldprojid = odn->dn_oldprojid;
937 ndn->dn_newuid = odn->dn_newuid;
938 ndn->dn_newgid = odn->dn_newgid;
939 ndn->dn_newprojid = odn->dn_newprojid;
940 ndn->dn_id_flags = odn->dn_id_flags;
941 dmu_zfetch_init(&ndn->dn_zfetch, ndn);
944 * Update back pointers. Updating the handle fixes the back pointer of
945 * every descendant dbuf as well as the bonus dbuf.
947 ASSERT(ndn->dn_handle->dnh_dnode == odn);
948 ndn->dn_handle->dnh_dnode = ndn;
951 * Invalidate the original dnode by clearing all of its back pointers.
954 odn->dn_handle = NULL;
955 avl_create(&odn->dn_dbufs, dbuf_compare, sizeof (dmu_buf_impl_t),
956 offsetof(dmu_buf_impl_t, db_link));
957 odn->dn_dbufs_count = 0;
958 odn->dn_bonus = NULL;
959 dmu_zfetch_fini(&odn->dn_zfetch);
962 * Set the low bit of the objset pointer to ensure that dnode_move()
963 * recognizes the dnode as invalid in any subsequent callback.
965 POINTER_INVALIDATE(&odn->dn_objset);
968 * Satisfy the destructor.
970 for (int i = 0; i < TXG_SIZE; i++) {
971 list_create(&odn->dn_dirty_records[i],
972 sizeof (dbuf_dirty_record_t),
973 offsetof(dbuf_dirty_record_t, dr_dirty_node));
974 odn->dn_free_ranges[i] = NULL;
975 odn->dn_next_nlevels[i] = 0;
976 odn->dn_next_indblkshift[i] = 0;
977 odn->dn_next_bonustype[i] = 0;
978 odn->dn_rm_spillblk[i] = 0;
979 odn->dn_next_bonuslen[i] = 0;
980 odn->dn_next_blksz[i] = 0;
982 odn->dn_allocated_txg = 0;
983 odn->dn_free_txg = 0;
984 odn->dn_assigned_txg = 0;
985 odn->dn_dirty_txg = 0;
986 odn->dn_dirtyctx = 0;
987 odn->dn_dirtyctx_firstset = NULL;
988 odn->dn_have_spill = B_FALSE;
991 odn->dn_oldflags = 0;
994 odn->dn_oldprojid = ZFS_DEFAULT_PROJID;
997 odn->dn_newprojid = ZFS_DEFAULT_PROJID;
998 odn->dn_id_flags = 0;
1004 odn->dn_moved = (uint8_t)-1;
1008 dnode_move(void *buf, void *newbuf, size_t size, void *arg)
1010 dnode_t *odn = buf, *ndn = newbuf;
1016 * The dnode is on the objset's list of known dnodes if the objset
1017 * pointer is valid. We set the low bit of the objset pointer when
1018 * freeing the dnode to invalidate it, and the memory patterns written
1019 * by kmem (baddcafe and deadbeef) set at least one of the two low bits.
1020 * A newly created dnode sets the objset pointer last of all to indicate
1021 * that the dnode is known and in a valid state to be moved by this
1024 os = odn->dn_objset;
1025 if (!POINTER_IS_VALID(os)) {
1026 DNODE_STAT_BUMP(dnode_move_invalid);
1027 return (KMEM_CBRC_DONT_KNOW);
1031 * Ensure that the objset does not go away during the move.
1033 rw_enter(&os_lock, RW_WRITER);
1034 if (os != odn->dn_objset) {
1036 DNODE_STAT_BUMP(dnode_move_recheck1);
1037 return (KMEM_CBRC_DONT_KNOW);
1041 * If the dnode is still valid, then so is the objset. We know that no
1042 * valid objset can be freed while we hold os_lock, so we can safely
1043 * ensure that the objset remains in use.
1045 mutex_enter(&os->os_lock);
1048 * Recheck the objset pointer in case the dnode was removed just before
1049 * acquiring the lock.
1051 if (os != odn->dn_objset) {
1052 mutex_exit(&os->os_lock);
1054 DNODE_STAT_BUMP(dnode_move_recheck2);
1055 return (KMEM_CBRC_DONT_KNOW);
1059 * At this point we know that as long as we hold os->os_lock, the dnode
1060 * cannot be freed and fields within the dnode can be safely accessed.
1061 * The objset listing this dnode cannot go away as long as this dnode is
1065 if (DMU_OBJECT_IS_SPECIAL(odn->dn_object)) {
1066 mutex_exit(&os->os_lock);
1067 DNODE_STAT_BUMP(dnode_move_special);
1068 return (KMEM_CBRC_NO);
1070 ASSERT(odn->dn_dbuf != NULL); /* only "special" dnodes have no parent */
1073 * Lock the dnode handle to prevent the dnode from obtaining any new
1074 * holds. This also prevents the descendant dbufs and the bonus dbuf
1075 * from accessing the dnode, so that we can discount their holds. The
1076 * handle is safe to access because we know that while the dnode cannot
1077 * go away, neither can its handle. Once we hold dnh_zrlock, we can
1078 * safely move any dnode referenced only by dbufs.
1080 if (!zrl_tryenter(&odn->dn_handle->dnh_zrlock)) {
1081 mutex_exit(&os->os_lock);
1082 DNODE_STAT_BUMP(dnode_move_handle);
1083 return (KMEM_CBRC_LATER);
1087 * Ensure a consistent view of the dnode's holds and the dnode's dbufs.
1088 * We need to guarantee that there is a hold for every dbuf in order to
1089 * determine whether the dnode is actively referenced. Falsely matching
1090 * a dbuf to an active hold would lead to an unsafe move. It's possible
1091 * that a thread already having an active dnode hold is about to add a
1092 * dbuf, and we can't compare hold and dbuf counts while the add is in
1095 if (!rw_tryenter(&odn->dn_struct_rwlock, RW_WRITER)) {
1096 zrl_exit(&odn->dn_handle->dnh_zrlock);
1097 mutex_exit(&os->os_lock);
1098 DNODE_STAT_BUMP(dnode_move_rwlock);
1099 return (KMEM_CBRC_LATER);
1103 * A dbuf may be removed (evicted) without an active dnode hold. In that
1104 * case, the dbuf count is decremented under the handle lock before the
1105 * dbuf's hold is released. This order ensures that if we count the hold
1106 * after the dbuf is removed but before its hold is released, we will
1107 * treat the unmatched hold as active and exit safely. If we count the
1108 * hold before the dbuf is removed, the hold is discounted, and the
1109 * removal is blocked until the move completes.
1111 refcount = zfs_refcount_count(&odn->dn_holds);
1112 ASSERT(refcount >= 0);
1113 dbufs = DN_DBUFS_COUNT(odn);
1115 /* We can't have more dbufs than dnode holds. */
1116 ASSERT3U(dbufs, <=, refcount);
1117 DTRACE_PROBE3(dnode__move, dnode_t *, odn, int64_t, refcount,
1120 if (refcount > dbufs) {
1121 rw_exit(&odn->dn_struct_rwlock);
1122 zrl_exit(&odn->dn_handle->dnh_zrlock);
1123 mutex_exit(&os->os_lock);
1124 DNODE_STAT_BUMP(dnode_move_active);
1125 return (KMEM_CBRC_LATER);
1128 rw_exit(&odn->dn_struct_rwlock);
1131 * At this point we know that anyone with a hold on the dnode is not
1132 * actively referencing it. The dnode is known and in a valid state to
1133 * move. We're holding the locks needed to execute the critical section.
1135 dnode_move_impl(odn, ndn);
1137 list_link_replace(&odn->dn_link, &ndn->dn_link);
1138 /* If the dnode was safe to move, the refcount cannot have changed. */
1139 ASSERT(refcount == zfs_refcount_count(&ndn->dn_holds));
1140 ASSERT(dbufs == DN_DBUFS_COUNT(ndn));
1141 zrl_exit(&ndn->dn_handle->dnh_zrlock); /* handle has moved */
1142 mutex_exit(&os->os_lock);
1144 return (KMEM_CBRC_YES);
1146 #endif /* _KERNEL */
1149 dnode_slots_hold(dnode_children_t *children, int idx, int slots)
1151 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK);
1153 for (int i = idx; i < idx + slots; i++) {
1154 dnode_handle_t *dnh = &children->dnc_children[i];
1155 zrl_add(&dnh->dnh_zrlock);
1160 dnode_slots_rele(dnode_children_t *children, int idx, int slots)
1162 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK);
1164 for (int i = idx; i < idx + slots; i++) {
1165 dnode_handle_t *dnh = &children->dnc_children[i];
1167 if (zrl_is_locked(&dnh->dnh_zrlock))
1168 zrl_exit(&dnh->dnh_zrlock);
1170 zrl_remove(&dnh->dnh_zrlock);
1175 dnode_slots_tryenter(dnode_children_t *children, int idx, int slots)
1177 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK);
1179 for (int i = idx; i < idx + slots; i++) {
1180 dnode_handle_t *dnh = &children->dnc_children[i];
1182 if (!zrl_tryenter(&dnh->dnh_zrlock)) {
1183 for (int j = idx; j < i; j++) {
1184 dnh = &children->dnc_children[j];
1185 zrl_exit(&dnh->dnh_zrlock);
1196 dnode_set_slots(dnode_children_t *children, int idx, int slots, void *ptr)
1198 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK);
1200 for (int i = idx; i < idx + slots; i++) {
1201 dnode_handle_t *dnh = &children->dnc_children[i];
1202 dnh->dnh_dnode = ptr;
1207 dnode_check_slots_free(dnode_children_t *children, int idx, int slots)
1209 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK);
1212 * If all dnode slots are either already free or
1213 * evictable return B_TRUE.
1215 for (int i = idx; i < idx + slots; i++) {
1216 dnode_handle_t *dnh = &children->dnc_children[i];
1217 dnode_t *dn = dnh->dnh_dnode;
1219 if (dn == DN_SLOT_FREE) {
1221 } else if (DN_SLOT_IS_PTR(dn)) {
1222 mutex_enter(&dn->dn_mtx);
1223 boolean_t can_free = (dn->dn_type == DMU_OT_NONE &&
1224 zfs_refcount_is_zero(&dn->dn_holds) &&
1225 !DNODE_IS_DIRTY(dn));
1226 mutex_exit(&dn->dn_mtx);
1241 dnode_reclaim_slots(dnode_children_t *children, int idx, int slots)
1243 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK);
1245 for (int i = idx; i < idx + slots; i++) {
1246 dnode_handle_t *dnh = &children->dnc_children[i];
1248 ASSERT(zrl_is_locked(&dnh->dnh_zrlock));
1250 if (DN_SLOT_IS_PTR(dnh->dnh_dnode)) {
1251 ASSERT3S(dnh->dnh_dnode->dn_type, ==, DMU_OT_NONE);
1252 dnode_destroy(dnh->dnh_dnode);
1253 dnh->dnh_dnode = DN_SLOT_FREE;
1259 dnode_free_interior_slots(dnode_t *dn)
1261 dnode_children_t *children = dmu_buf_get_user(&dn->dn_dbuf->db);
1262 int epb = dn->dn_dbuf->db.db_size >> DNODE_SHIFT;
1263 int idx = (dn->dn_object & (epb - 1)) + 1;
1264 int slots = dn->dn_num_slots - 1;
1269 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK);
1271 while (!dnode_slots_tryenter(children, idx, slots)) {
1272 DNODE_STAT_BUMP(dnode_free_interior_lock_retry);
1273 kpreempt(KPREEMPT_SYNC);
1276 dnode_set_slots(children, idx, slots, DN_SLOT_FREE);
1277 dnode_slots_rele(children, idx, slots);
1281 dnode_special_close(dnode_handle_t *dnh)
1283 dnode_t *dn = dnh->dnh_dnode;
1286 * Ensure dnode_rele_and_unlock() has released dn_mtx, after final
1287 * zfs_refcount_remove()
1289 mutex_enter(&dn->dn_mtx);
1290 if (zfs_refcount_count(&dn->dn_holds) > 0)
1291 cv_wait(&dn->dn_nodnholds, &dn->dn_mtx);
1292 mutex_exit(&dn->dn_mtx);
1293 ASSERT3U(zfs_refcount_count(&dn->dn_holds), ==, 0);
1295 ASSERT(dn->dn_dbuf == NULL ||
1296 dmu_buf_get_user(&dn->dn_dbuf->db) == NULL);
1297 zrl_add(&dnh->dnh_zrlock);
1298 dnode_destroy(dn); /* implicit zrl_remove() */
1299 zrl_destroy(&dnh->dnh_zrlock);
1300 dnh->dnh_dnode = NULL;
1304 dnode_special_open(objset_t *os, dnode_phys_t *dnp, uint64_t object,
1305 dnode_handle_t *dnh)
1309 zrl_init(&dnh->dnh_zrlock);
1310 VERIFY3U(1, ==, zrl_tryenter(&dnh->dnh_zrlock));
1312 dn = dnode_create(os, dnp, NULL, object, dnh);
1315 zrl_exit(&dnh->dnh_zrlock);
1319 dnode_buf_evict_async(void *dbu)
1321 dnode_children_t *dnc = dbu;
1323 DNODE_STAT_BUMP(dnode_buf_evict);
1325 for (int i = 0; i < dnc->dnc_count; i++) {
1326 dnode_handle_t *dnh = &dnc->dnc_children[i];
1330 * The dnode handle lock guards against the dnode moving to
1331 * another valid address, so there is no need here to guard
1332 * against changes to or from NULL.
1334 if (!DN_SLOT_IS_PTR(dnh->dnh_dnode)) {
1335 zrl_destroy(&dnh->dnh_zrlock);
1336 dnh->dnh_dnode = DN_SLOT_UNINIT;
1340 zrl_add(&dnh->dnh_zrlock);
1341 dn = dnh->dnh_dnode;
1343 * If there are holds on this dnode, then there should
1344 * be holds on the dnode's containing dbuf as well; thus
1345 * it wouldn't be eligible for eviction and this function
1346 * would not have been called.
1348 ASSERT(zfs_refcount_is_zero(&dn->dn_holds));
1349 ASSERT(zfs_refcount_is_zero(&dn->dn_tx_holds));
1351 dnode_destroy(dn); /* implicit zrl_remove() for first slot */
1352 zrl_destroy(&dnh->dnh_zrlock);
1353 dnh->dnh_dnode = DN_SLOT_UNINIT;
1355 kmem_free(dnc, sizeof (dnode_children_t) +
1356 dnc->dnc_count * sizeof (dnode_handle_t));
1360 * When the DNODE_MUST_BE_FREE flag is set, the "slots" parameter is used
1361 * to ensure the hole at the specified object offset is large enough to
1362 * hold the dnode being created. The slots parameter is also used to ensure
1363 * a dnode does not span multiple dnode blocks. In both of these cases, if
1364 * a failure occurs, ENOSPC is returned. Keep in mind, these failure cases
1365 * are only possible when using DNODE_MUST_BE_FREE.
1367 * If the DNODE_MUST_BE_ALLOCATED flag is set, "slots" must be 0.
1368 * dnode_hold_impl() will check if the requested dnode is already consumed
1369 * as an extra dnode slot by an large dnode, in which case it returns
1372 * If the DNODE_DRY_RUN flag is set, we don't actually hold the dnode, just
1373 * return whether the hold would succeed or not. tag and dnp should set to
1374 * NULL in this case.
1377 * EINVAL - Invalid object number or flags.
1378 * ENOSPC - Hole too small to fulfill "slots" request (DNODE_MUST_BE_FREE)
1379 * EEXIST - Refers to an allocated dnode (DNODE_MUST_BE_FREE)
1380 * - Refers to a freeing dnode (DNODE_MUST_BE_FREE)
1381 * - Refers to an interior dnode slot (DNODE_MUST_BE_ALLOCATED)
1382 * ENOENT - The requested dnode is not allocated (DNODE_MUST_BE_ALLOCATED)
1383 * - The requested dnode is being freed (DNODE_MUST_BE_ALLOCATED)
1384 * EIO - I/O error when reading the meta dnode dbuf.
1386 * succeeds even for free dnodes.
1389 dnode_hold_impl(objset_t *os, uint64_t object, int flag, int slots,
1390 const void *tag, dnode_t **dnp)
1393 int drop_struct_lock = FALSE;
1398 dnode_children_t *dnc;
1399 dnode_phys_t *dn_block;
1400 dnode_handle_t *dnh;
1402 ASSERT(!(flag & DNODE_MUST_BE_ALLOCATED) || (slots == 0));
1403 ASSERT(!(flag & DNODE_MUST_BE_FREE) || (slots > 0));
1404 IMPLY(flag & DNODE_DRY_RUN, (tag == NULL) && (dnp == NULL));
1407 * If you are holding the spa config lock as writer, you shouldn't
1408 * be asking the DMU to do *anything* unless it's the root pool
1409 * which may require us to read from the root filesystem while
1410 * holding some (not all) of the locks as writer.
1412 ASSERT(spa_config_held(os->os_spa, SCL_ALL, RW_WRITER) == 0 ||
1413 (spa_is_root(os->os_spa) &&
1414 spa_config_held(os->os_spa, SCL_STATE, RW_WRITER)));
1416 ASSERT((flag & DNODE_MUST_BE_ALLOCATED) || (flag & DNODE_MUST_BE_FREE));
1418 if (object == DMU_USERUSED_OBJECT || object == DMU_GROUPUSED_OBJECT ||
1419 object == DMU_PROJECTUSED_OBJECT) {
1420 if (object == DMU_USERUSED_OBJECT)
1421 dn = DMU_USERUSED_DNODE(os);
1422 else if (object == DMU_GROUPUSED_OBJECT)
1423 dn = DMU_GROUPUSED_DNODE(os);
1425 dn = DMU_PROJECTUSED_DNODE(os);
1427 return (SET_ERROR(ENOENT));
1429 if ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE)
1430 return (SET_ERROR(ENOENT));
1431 if ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE)
1432 return (SET_ERROR(EEXIST));
1434 /* Don't actually hold if dry run, just return 0 */
1435 if (!(flag & DNODE_DRY_RUN)) {
1436 (void) zfs_refcount_add(&dn->dn_holds, tag);
1442 if (object == 0 || object >= DN_MAX_OBJECT)
1443 return (SET_ERROR(EINVAL));
1445 mdn = DMU_META_DNODE(os);
1446 ASSERT(mdn->dn_object == DMU_META_DNODE_OBJECT);
1450 if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) {
1451 rw_enter(&mdn->dn_struct_rwlock, RW_READER);
1452 drop_struct_lock = TRUE;
1455 blk = dbuf_whichblock(mdn, 0, object * sizeof (dnode_phys_t));
1456 db = dbuf_hold(mdn, blk, FTAG);
1457 if (drop_struct_lock)
1458 rw_exit(&mdn->dn_struct_rwlock);
1460 DNODE_STAT_BUMP(dnode_hold_dbuf_hold);
1461 return (SET_ERROR(EIO));
1465 * We do not need to decrypt to read the dnode so it doesn't matter
1466 * if we get the encrypted or decrypted version.
1468 err = dbuf_read(db, NULL, DB_RF_CANFAIL |
1469 DB_RF_NO_DECRYPT | DB_RF_NOPREFETCH);
1471 DNODE_STAT_BUMP(dnode_hold_dbuf_read);
1472 dbuf_rele(db, FTAG);
1476 ASSERT3U(db->db.db_size, >=, 1<<DNODE_SHIFT);
1477 epb = db->db.db_size >> DNODE_SHIFT;
1479 idx = object & (epb - 1);
1480 dn_block = (dnode_phys_t *)db->db.db_data;
1482 ASSERT(DB_DNODE(db)->dn_type == DMU_OT_DNODE);
1483 dnc = dmu_buf_get_user(&db->db);
1486 dnode_children_t *winner;
1489 dnc = kmem_zalloc(sizeof (dnode_children_t) +
1490 epb * sizeof (dnode_handle_t), KM_SLEEP);
1491 dnc->dnc_count = epb;
1492 dnh = &dnc->dnc_children[0];
1494 /* Initialize dnode slot status from dnode_phys_t */
1495 for (int i = 0; i < epb; i++) {
1496 zrl_init(&dnh[i].dnh_zrlock);
1503 if (dn_block[i].dn_type != DMU_OT_NONE) {
1504 int interior = dn_block[i].dn_extra_slots;
1506 dnode_set_slots(dnc, i, 1, DN_SLOT_ALLOCATED);
1507 dnode_set_slots(dnc, i + 1, interior,
1511 dnh[i].dnh_dnode = DN_SLOT_FREE;
1516 dmu_buf_init_user(&dnc->dnc_dbu, NULL,
1517 dnode_buf_evict_async, NULL);
1518 winner = dmu_buf_set_user(&db->db, &dnc->dnc_dbu);
1519 if (winner != NULL) {
1521 for (int i = 0; i < epb; i++)
1522 zrl_destroy(&dnh[i].dnh_zrlock);
1524 kmem_free(dnc, sizeof (dnode_children_t) +
1525 epb * sizeof (dnode_handle_t));
1530 ASSERT(dnc->dnc_count == epb);
1532 if (flag & DNODE_MUST_BE_ALLOCATED) {
1535 dnode_slots_hold(dnc, idx, slots);
1536 dnh = &dnc->dnc_children[idx];
1538 if (DN_SLOT_IS_PTR(dnh->dnh_dnode)) {
1539 dn = dnh->dnh_dnode;
1540 } else if (dnh->dnh_dnode == DN_SLOT_INTERIOR) {
1541 DNODE_STAT_BUMP(dnode_hold_alloc_interior);
1542 dnode_slots_rele(dnc, idx, slots);
1543 dbuf_rele(db, FTAG);
1544 return (SET_ERROR(EEXIST));
1545 } else if (dnh->dnh_dnode != DN_SLOT_ALLOCATED) {
1546 DNODE_STAT_BUMP(dnode_hold_alloc_misses);
1547 dnode_slots_rele(dnc, idx, slots);
1548 dbuf_rele(db, FTAG);
1549 return (SET_ERROR(ENOENT));
1551 dnode_slots_rele(dnc, idx, slots);
1552 while (!dnode_slots_tryenter(dnc, idx, slots)) {
1553 DNODE_STAT_BUMP(dnode_hold_alloc_lock_retry);
1554 kpreempt(KPREEMPT_SYNC);
1558 * Someone else won the race and called dnode_create()
1559 * after we checked DN_SLOT_IS_PTR() above but before
1560 * we acquired the lock.
1562 if (DN_SLOT_IS_PTR(dnh->dnh_dnode)) {
1563 DNODE_STAT_BUMP(dnode_hold_alloc_lock_misses);
1564 dn = dnh->dnh_dnode;
1566 dn = dnode_create(os, dn_block + idx, db,
1571 mutex_enter(&dn->dn_mtx);
1572 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg != 0) {
1573 DNODE_STAT_BUMP(dnode_hold_alloc_type_none);
1574 mutex_exit(&dn->dn_mtx);
1575 dnode_slots_rele(dnc, idx, slots);
1576 dbuf_rele(db, FTAG);
1577 return (SET_ERROR(ENOENT));
1580 /* Don't actually hold if dry run, just return 0 */
1581 if (flag & DNODE_DRY_RUN) {
1582 mutex_exit(&dn->dn_mtx);
1583 dnode_slots_rele(dnc, idx, slots);
1584 dbuf_rele(db, FTAG);
1588 DNODE_STAT_BUMP(dnode_hold_alloc_hits);
1589 } else if (flag & DNODE_MUST_BE_FREE) {
1591 if (idx + slots - 1 >= DNODES_PER_BLOCK) {
1592 DNODE_STAT_BUMP(dnode_hold_free_overflow);
1593 dbuf_rele(db, FTAG);
1594 return (SET_ERROR(ENOSPC));
1597 dnode_slots_hold(dnc, idx, slots);
1599 if (!dnode_check_slots_free(dnc, idx, slots)) {
1600 DNODE_STAT_BUMP(dnode_hold_free_misses);
1601 dnode_slots_rele(dnc, idx, slots);
1602 dbuf_rele(db, FTAG);
1603 return (SET_ERROR(ENOSPC));
1606 dnode_slots_rele(dnc, idx, slots);
1607 while (!dnode_slots_tryenter(dnc, idx, slots)) {
1608 DNODE_STAT_BUMP(dnode_hold_free_lock_retry);
1609 kpreempt(KPREEMPT_SYNC);
1612 if (!dnode_check_slots_free(dnc, idx, slots)) {
1613 DNODE_STAT_BUMP(dnode_hold_free_lock_misses);
1614 dnode_slots_rele(dnc, idx, slots);
1615 dbuf_rele(db, FTAG);
1616 return (SET_ERROR(ENOSPC));
1620 * Allocated but otherwise free dnodes which would
1621 * be in the interior of a multi-slot dnodes need
1622 * to be freed. Single slot dnodes can be safely
1623 * re-purposed as a performance optimization.
1626 dnode_reclaim_slots(dnc, idx + 1, slots - 1);
1628 dnh = &dnc->dnc_children[idx];
1629 if (DN_SLOT_IS_PTR(dnh->dnh_dnode)) {
1630 dn = dnh->dnh_dnode;
1632 dn = dnode_create(os, dn_block + idx, db,
1636 mutex_enter(&dn->dn_mtx);
1637 if (!zfs_refcount_is_zero(&dn->dn_holds) || dn->dn_free_txg) {
1638 DNODE_STAT_BUMP(dnode_hold_free_refcount);
1639 mutex_exit(&dn->dn_mtx);
1640 dnode_slots_rele(dnc, idx, slots);
1641 dbuf_rele(db, FTAG);
1642 return (SET_ERROR(EEXIST));
1645 /* Don't actually hold if dry run, just return 0 */
1646 if (flag & DNODE_DRY_RUN) {
1647 mutex_exit(&dn->dn_mtx);
1648 dnode_slots_rele(dnc, idx, slots);
1649 dbuf_rele(db, FTAG);
1653 dnode_set_slots(dnc, idx + 1, slots - 1, DN_SLOT_INTERIOR);
1654 DNODE_STAT_BUMP(dnode_hold_free_hits);
1656 dbuf_rele(db, FTAG);
1657 return (SET_ERROR(EINVAL));
1660 ASSERT0(dn->dn_free_txg);
1662 if (zfs_refcount_add(&dn->dn_holds, tag) == 1)
1663 dbuf_add_ref(db, dnh);
1665 mutex_exit(&dn->dn_mtx);
1667 /* Now we can rely on the hold to prevent the dnode from moving. */
1668 dnode_slots_rele(dnc, idx, slots);
1671 ASSERT3P(dnp, !=, NULL);
1672 ASSERT3P(dn->dn_dbuf, ==, db);
1673 ASSERT3U(dn->dn_object, ==, object);
1674 dbuf_rele(db, FTAG);
1681 * Return held dnode if the object is allocated, NULL if not.
1684 dnode_hold(objset_t *os, uint64_t object, const void *tag, dnode_t **dnp)
1686 return (dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, 0, tag,
1691 * Can only add a reference if there is already at least one
1692 * reference on the dnode. Returns FALSE if unable to add a
1696 dnode_add_ref(dnode_t *dn, const void *tag)
1698 mutex_enter(&dn->dn_mtx);
1699 if (zfs_refcount_is_zero(&dn->dn_holds)) {
1700 mutex_exit(&dn->dn_mtx);
1703 VERIFY(1 < zfs_refcount_add(&dn->dn_holds, tag));
1704 mutex_exit(&dn->dn_mtx);
1709 dnode_rele(dnode_t *dn, const void *tag)
1711 mutex_enter(&dn->dn_mtx);
1712 dnode_rele_and_unlock(dn, tag, B_FALSE);
1716 dnode_rele_and_unlock(dnode_t *dn, const void *tag, boolean_t evicting)
1719 /* Get while the hold prevents the dnode from moving. */
1720 dmu_buf_impl_t *db = dn->dn_dbuf;
1721 dnode_handle_t *dnh = dn->dn_handle;
1723 refs = zfs_refcount_remove(&dn->dn_holds, tag);
1725 cv_broadcast(&dn->dn_nodnholds);
1726 mutex_exit(&dn->dn_mtx);
1727 /* dnode could get destroyed at this point, so don't use it anymore */
1730 * It's unsafe to release the last hold on a dnode by dnode_rele() or
1731 * indirectly by dbuf_rele() while relying on the dnode handle to
1732 * prevent the dnode from moving, since releasing the last hold could
1733 * result in the dnode's parent dbuf evicting its dnode handles. For
1734 * that reason anyone calling dnode_rele() or dbuf_rele() without some
1735 * other direct or indirect hold on the dnode must first drop the dnode
1739 ASSERT(refs > 0 || dnh->dnh_zrlock.zr_owner != curthread);
1742 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */
1743 if (refs == 0 && db != NULL) {
1745 * Another thread could add a hold to the dnode handle in
1746 * dnode_hold_impl() while holding the parent dbuf. Since the
1747 * hold on the parent dbuf prevents the handle from being
1748 * destroyed, the hold on the handle is OK. We can't yet assert
1749 * that the handle has zero references, but that will be
1750 * asserted anyway when the handle gets destroyed.
1752 mutex_enter(&db->db_mtx);
1753 dbuf_rele_and_unlock(db, dnh, evicting);
1758 * Test whether we can create a dnode at the specified location.
1761 dnode_try_claim(objset_t *os, uint64_t object, int slots)
1763 return (dnode_hold_impl(os, object, DNODE_MUST_BE_FREE | DNODE_DRY_RUN,
1764 slots, NULL, NULL));
1768 * Checks if the dnode contains any uncommitted dirty records.
1771 dnode_is_dirty(dnode_t *dn)
1773 mutex_enter(&dn->dn_mtx);
1775 for (int i = 0; i < TXG_SIZE; i++) {
1776 if (multilist_link_active(&dn->dn_dirty_link[i])) {
1777 mutex_exit(&dn->dn_mtx);
1782 mutex_exit(&dn->dn_mtx);
1788 dnode_setdirty(dnode_t *dn, dmu_tx_t *tx)
1790 objset_t *os = dn->dn_objset;
1791 uint64_t txg = tx->tx_txg;
1793 if (DMU_OBJECT_IS_SPECIAL(dn->dn_object)) {
1794 dsl_dataset_dirty(os->os_dsl_dataset, tx);
1801 mutex_enter(&dn->dn_mtx);
1802 ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg);
1803 ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg);
1804 mutex_exit(&dn->dn_mtx);
1808 * Determine old uid/gid when necessary
1810 dmu_objset_userquota_get_ids(dn, B_TRUE, tx);
1812 multilist_t *dirtylist = &os->os_dirty_dnodes[txg & TXG_MASK];
1813 multilist_sublist_t *mls = multilist_sublist_lock_obj(dirtylist, dn);
1816 * If we are already marked dirty, we're done.
1818 if (multilist_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) {
1819 multilist_sublist_unlock(mls);
1823 ASSERT(!zfs_refcount_is_zero(&dn->dn_holds) ||
1824 !avl_is_empty(&dn->dn_dbufs));
1825 ASSERT(dn->dn_datablksz != 0);
1826 ASSERT0(dn->dn_next_bonuslen[txg & TXG_MASK]);
1827 ASSERT0(dn->dn_next_blksz[txg & TXG_MASK]);
1828 ASSERT0(dn->dn_next_bonustype[txg & TXG_MASK]);
1830 dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n",
1831 (u_longlong_t)dn->dn_object, (u_longlong_t)txg);
1833 multilist_sublist_insert_head(mls, dn);
1835 multilist_sublist_unlock(mls);
1838 * The dnode maintains a hold on its containing dbuf as
1839 * long as there are holds on it. Each instantiated child
1840 * dbuf maintains a hold on the dnode. When the last child
1841 * drops its hold, the dnode will drop its hold on the
1842 * containing dbuf. We add a "dirty hold" here so that the
1843 * dnode will hang around after we finish processing its
1846 VERIFY(dnode_add_ref(dn, (void *)(uintptr_t)tx->tx_txg));
1848 (void) dbuf_dirty(dn->dn_dbuf, tx);
1850 dsl_dataset_dirty(os->os_dsl_dataset, tx);
1854 dnode_free(dnode_t *dn, dmu_tx_t *tx)
1856 mutex_enter(&dn->dn_mtx);
1857 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) {
1858 mutex_exit(&dn->dn_mtx);
1861 dn->dn_free_txg = tx->tx_txg;
1862 mutex_exit(&dn->dn_mtx);
1864 dnode_setdirty(dn, tx);
1868 * Try to change the block size for the indicated dnode. This can only
1869 * succeed if there are no blocks allocated or dirty beyond first block
1872 dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx)
1877 ASSERT3U(size, <=, spa_maxblocksize(dmu_objset_spa(dn->dn_objset)));
1879 size = SPA_MINBLOCKSIZE;
1881 size = P2ROUNDUP(size, SPA_MINBLOCKSIZE);
1883 if (ibs == dn->dn_indblkshift)
1886 if (size == dn->dn_datablksz && ibs == 0)
1889 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
1891 /* Check for any allocated blocks beyond the first */
1892 if (dn->dn_maxblkid != 0)
1895 mutex_enter(&dn->dn_dbufs_mtx);
1896 for (db = avl_first(&dn->dn_dbufs); db != NULL;
1897 db = AVL_NEXT(&dn->dn_dbufs, db)) {
1898 if (db->db_blkid != 0 && db->db_blkid != DMU_BONUS_BLKID &&
1899 db->db_blkid != DMU_SPILL_BLKID) {
1900 mutex_exit(&dn->dn_dbufs_mtx);
1904 mutex_exit(&dn->dn_dbufs_mtx);
1906 if (ibs && dn->dn_nlevels != 1)
1909 dnode_setdirty(dn, tx);
1910 if (size != dn->dn_datablksz) {
1911 /* resize the old block */
1912 err = dbuf_hold_impl(dn, 0, 0, TRUE, FALSE, FTAG, &db);
1914 dbuf_new_size(db, size, tx);
1915 } else if (err != ENOENT) {
1919 dnode_setdblksz(dn, size);
1920 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = size;
1922 dbuf_rele(db, FTAG);
1925 dn->dn_indblkshift = ibs;
1926 dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs;
1929 rw_exit(&dn->dn_struct_rwlock);
1933 rw_exit(&dn->dn_struct_rwlock);
1934 return (SET_ERROR(ENOTSUP));
1938 dnode_set_nlevels_impl(dnode_t *dn, int new_nlevels, dmu_tx_t *tx)
1940 uint64_t txgoff = tx->tx_txg & TXG_MASK;
1941 int old_nlevels = dn->dn_nlevels;
1944 dbuf_dirty_record_t *new, *dr, *dr_next;
1946 ASSERT(RW_WRITE_HELD(&dn->dn_struct_rwlock));
1948 ASSERT3U(new_nlevels, >, dn->dn_nlevels);
1949 dn->dn_nlevels = new_nlevels;
1951 ASSERT3U(new_nlevels, >, dn->dn_next_nlevels[txgoff]);
1952 dn->dn_next_nlevels[txgoff] = new_nlevels;
1954 /* dirty the left indirects */
1955 db = dbuf_hold_level(dn, old_nlevels, 0, FTAG);
1957 new = dbuf_dirty(db, tx);
1958 dbuf_rele(db, FTAG);
1960 /* transfer the dirty records to the new indirect */
1961 mutex_enter(&dn->dn_mtx);
1962 mutex_enter(&new->dt.di.dr_mtx);
1963 list = &dn->dn_dirty_records[txgoff];
1964 for (dr = list_head(list); dr; dr = dr_next) {
1965 dr_next = list_next(&dn->dn_dirty_records[txgoff], dr);
1967 IMPLY(dr->dr_dbuf == NULL, old_nlevels == 1);
1968 if (dr->dr_dbuf == NULL ||
1969 (dr->dr_dbuf->db_level == old_nlevels - 1 &&
1970 dr->dr_dbuf->db_blkid != DMU_BONUS_BLKID &&
1971 dr->dr_dbuf->db_blkid != DMU_SPILL_BLKID)) {
1972 list_remove(&dn->dn_dirty_records[txgoff], dr);
1973 list_insert_tail(&new->dt.di.dr_children, dr);
1974 dr->dr_parent = new;
1977 mutex_exit(&new->dt.di.dr_mtx);
1978 mutex_exit(&dn->dn_mtx);
1982 dnode_set_nlevels(dnode_t *dn, int nlevels, dmu_tx_t *tx)
1986 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
1988 if (dn->dn_nlevels == nlevels) {
1991 } else if (nlevels < dn->dn_nlevels) {
1992 ret = SET_ERROR(EINVAL);
1996 dnode_set_nlevels_impl(dn, nlevels, tx);
1999 rw_exit(&dn->dn_struct_rwlock);
2003 /* read-holding callers must not rely on the lock being continuously held */
2005 dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx, boolean_t have_read,
2008 int epbs, new_nlevels;
2011 ASSERT(blkid != DMU_BONUS_BLKID);
2014 RW_READ_HELD(&dn->dn_struct_rwlock) :
2015 RW_WRITE_HELD(&dn->dn_struct_rwlock));
2018 * if we have a read-lock, check to see if we need to do any work
2019 * before upgrading to a write-lock.
2022 if (blkid <= dn->dn_maxblkid)
2025 if (!rw_tryupgrade(&dn->dn_struct_rwlock)) {
2026 rw_exit(&dn->dn_struct_rwlock);
2027 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
2032 * Raw sends (indicated by the force flag) require that we take the
2033 * given blkid even if the value is lower than the current value.
2035 if (!force && blkid <= dn->dn_maxblkid)
2039 * We use the (otherwise unused) top bit of dn_next_maxblkid[txgoff]
2040 * to indicate that this field is set. This allows us to set the
2041 * maxblkid to 0 on an existing object in dnode_sync().
2043 dn->dn_maxblkid = blkid;
2044 dn->dn_next_maxblkid[tx->tx_txg & TXG_MASK] =
2045 blkid | DMU_NEXT_MAXBLKID_SET;
2048 * Compute the number of levels necessary to support the new maxblkid.
2049 * Raw sends will ensure nlevels is set correctly for us.
2052 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT;
2053 for (sz = dn->dn_nblkptr;
2054 sz <= blkid && sz >= dn->dn_nblkptr; sz <<= epbs)
2057 ASSERT3U(new_nlevels, <=, DN_MAX_LEVELS);
2060 if (new_nlevels > dn->dn_nlevels)
2061 dnode_set_nlevels_impl(dn, new_nlevels, tx);
2063 ASSERT3U(dn->dn_nlevels, >=, new_nlevels);
2068 rw_downgrade(&dn->dn_struct_rwlock);
2072 dnode_dirty_l1(dnode_t *dn, uint64_t l1blkid, dmu_tx_t *tx)
2074 dmu_buf_impl_t *db = dbuf_hold_level(dn, 1, l1blkid, FTAG);
2076 dmu_buf_will_dirty(&db->db, tx);
2077 dbuf_rele(db, FTAG);
2082 * Dirty all the in-core level-1 dbufs in the range specified by start_blkid
2086 dnode_dirty_l1range(dnode_t *dn, uint64_t start_blkid, uint64_t end_blkid,
2089 dmu_buf_impl_t *db_search;
2093 db_search = kmem_zalloc(sizeof (dmu_buf_impl_t), KM_SLEEP);
2095 mutex_enter(&dn->dn_dbufs_mtx);
2097 db_search->db_level = 1;
2098 db_search->db_blkid = start_blkid + 1;
2099 db_search->db_state = DB_SEARCH;
2102 db = avl_find(&dn->dn_dbufs, db_search, &where);
2104 db = avl_nearest(&dn->dn_dbufs, where, AVL_AFTER);
2106 if (db == NULL || db->db_level != 1 ||
2107 db->db_blkid >= end_blkid) {
2112 * Setup the next blkid we want to search for.
2114 db_search->db_blkid = db->db_blkid + 1;
2115 ASSERT3U(db->db_blkid, >=, start_blkid);
2118 * If the dbuf transitions to DB_EVICTING while we're trying
2119 * to dirty it, then we will be unable to discover it in
2120 * the dbuf hash table. This will result in a call to
2121 * dbuf_create() which needs to acquire the dn_dbufs_mtx
2122 * lock. To avoid a deadlock, we drop the lock before
2123 * dirtying the level-1 dbuf.
2125 mutex_exit(&dn->dn_dbufs_mtx);
2126 dnode_dirty_l1(dn, db->db_blkid, tx);
2127 mutex_enter(&dn->dn_dbufs_mtx);
2132 * Walk all the in-core level-1 dbufs and verify they have been dirtied.
2134 db_search->db_level = 1;
2135 db_search->db_blkid = start_blkid + 1;
2136 db_search->db_state = DB_SEARCH;
2137 db = avl_find(&dn->dn_dbufs, db_search, &where);
2139 db = avl_nearest(&dn->dn_dbufs, where, AVL_AFTER);
2140 for (; db != NULL; db = AVL_NEXT(&dn->dn_dbufs, db)) {
2141 if (db->db_level != 1 || db->db_blkid >= end_blkid)
2143 if (db->db_state != DB_EVICTING)
2144 ASSERT(db->db_dirtycnt > 0);
2147 kmem_free(db_search, sizeof (dmu_buf_impl_t));
2148 mutex_exit(&dn->dn_dbufs_mtx);
2152 dnode_set_dirtyctx(dnode_t *dn, dmu_tx_t *tx, const void *tag)
2155 * Don't set dirtyctx to SYNC if we're just modifying this as we
2156 * initialize the objset.
2158 if (dn->dn_dirtyctx == DN_UNDIRTIED) {
2159 dsl_dataset_t *ds = dn->dn_objset->os_dsl_dataset;
2162 rrw_enter(&ds->ds_bp_rwlock, RW_READER, tag);
2164 if (!BP_IS_HOLE(dn->dn_objset->os_rootbp)) {
2165 if (dmu_tx_is_syncing(tx))
2166 dn->dn_dirtyctx = DN_DIRTY_SYNC;
2168 dn->dn_dirtyctx = DN_DIRTY_OPEN;
2169 dn->dn_dirtyctx_firstset = tag;
2172 rrw_exit(&ds->ds_bp_rwlock, tag);
2178 dnode_partial_zero(dnode_t *dn, uint64_t off, uint64_t blkoff, uint64_t len,
2184 rw_enter(&dn->dn_struct_rwlock, RW_READER);
2185 res = dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, 0, off), TRUE, FALSE,
2187 rw_exit(&dn->dn_struct_rwlock);
2189 db_lock_type_t dblt;
2192 dblt = dmu_buf_lock_parent(db, RW_READER, FTAG);
2193 /* don't dirty if not on disk and not dirty */
2194 dirty = !list_is_empty(&db->db_dirty_records) ||
2195 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr));
2196 dmu_buf_unlock_parent(db, dblt, FTAG);
2200 dmu_buf_will_dirty(&db->db, tx);
2201 data = db->db.db_data;
2202 memset(data + blkoff, 0, len);
2204 dbuf_rele(db, FTAG);
2209 dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx)
2211 uint64_t blkoff, blkid, nblks;
2212 int blksz, blkshift, head, tail;
2216 blksz = dn->dn_datablksz;
2217 blkshift = dn->dn_datablkshift;
2218 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT;
2220 if (len == DMU_OBJECT_END) {
2221 len = UINT64_MAX - off;
2226 * First, block align the region to free:
2229 head = P2NPHASE(off, blksz);
2230 blkoff = P2PHASE(off, blksz);
2231 if ((off >> blkshift) > dn->dn_maxblkid)
2234 ASSERT(dn->dn_maxblkid == 0);
2235 if (off == 0 && len >= blksz) {
2237 * Freeing the whole block; fast-track this request.
2241 if (dn->dn_nlevels > 1) {
2242 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
2243 dnode_dirty_l1(dn, 0, tx);
2244 rw_exit(&dn->dn_struct_rwlock);
2247 } else if (off >= blksz) {
2248 /* Freeing past end-of-data */
2251 /* Freeing part of the block. */
2253 ASSERT3U(head, >, 0);
2257 /* zero out any partial block data at the start of the range */
2259 ASSERT3U(blkoff + head, ==, blksz);
2262 dnode_partial_zero(dn, off, blkoff, head, tx);
2267 /* If the range was less than one block, we're done */
2271 /* If the remaining range is past end of file, we're done */
2272 if ((off >> blkshift) > dn->dn_maxblkid)
2275 ASSERT(ISP2(blksz));
2279 tail = P2PHASE(len, blksz);
2281 ASSERT0(P2PHASE(off, blksz));
2282 /* zero out any partial block data at the end of the range */
2286 dnode_partial_zero(dn, off + len, 0, tail, tx);
2290 /* If the range did not include a full block, we are done */
2294 ASSERT(IS_P2ALIGNED(off, blksz));
2295 ASSERT(trunc || IS_P2ALIGNED(len, blksz));
2296 blkid = off >> blkshift;
2297 nblks = len >> blkshift;
2302 * Dirty all the indirect blocks in this range. Note that only
2303 * the first and last indirect blocks can actually be written
2304 * (if they were partially freed) -- they must be dirtied, even if
2305 * they do not exist on disk yet. The interior blocks will
2306 * be freed by free_children(), so they will not actually be written.
2307 * Even though these interior blocks will not be written, we
2308 * dirty them for two reasons:
2310 * - It ensures that the indirect blocks remain in memory until
2311 * syncing context. (They have already been prefetched by
2312 * dmu_tx_hold_free(), so we don't have to worry about reading
2313 * them serially here.)
2315 * - The dirty space accounting will put pressure on the txg sync
2316 * mechanism to begin syncing, and to delay transactions if there
2317 * is a large amount of freeing. Even though these indirect
2318 * blocks will not be written, we could need to write the same
2319 * amount of space if we copy the freed BPs into deadlists.
2321 if (dn->dn_nlevels > 1) {
2322 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
2323 uint64_t first, last;
2325 first = blkid >> epbs;
2326 dnode_dirty_l1(dn, first, tx);
2328 last = dn->dn_maxblkid >> epbs;
2330 last = (blkid + nblks - 1) >> epbs;
2332 dnode_dirty_l1(dn, last, tx);
2334 dnode_dirty_l1range(dn, first, last, tx);
2336 int shift = dn->dn_datablkshift + dn->dn_indblkshift -
2338 for (uint64_t i = first + 1; i < last; i++) {
2340 * Set i to the blockid of the next non-hole
2341 * level-1 indirect block at or after i. Note
2342 * that dnode_next_offset() operates in terms of
2343 * level-0-equivalent bytes.
2345 uint64_t ibyte = i << shift;
2346 int err = dnode_next_offset(dn, DNODE_FIND_HAVELOCK,
2353 * Normally we should not see an error, either
2354 * from dnode_next_offset() or dbuf_hold_level()
2355 * (except for ESRCH from dnode_next_offset).
2356 * If there is an i/o error, then when we read
2357 * this block in syncing context, it will use
2358 * ZIO_FLAG_MUSTSUCCEED, and thus hang/panic according
2359 * to the "failmode" property. dnode_next_offset()
2360 * doesn't have a flag to indicate MUSTSUCCEED.
2365 dnode_dirty_l1(dn, i, tx);
2367 rw_exit(&dn->dn_struct_rwlock);
2372 * Add this range to the dnode range list.
2373 * We will finish up this free operation in the syncing phase.
2375 mutex_enter(&dn->dn_mtx);
2377 int txgoff = tx->tx_txg & TXG_MASK;
2378 if (dn->dn_free_ranges[txgoff] == NULL) {
2379 dn->dn_free_ranges[txgoff] = range_tree_create(NULL,
2380 RANGE_SEG64, NULL, 0, 0);
2382 range_tree_clear(dn->dn_free_ranges[txgoff], blkid, nblks);
2383 range_tree_add(dn->dn_free_ranges[txgoff], blkid, nblks);
2385 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n",
2386 (u_longlong_t)blkid, (u_longlong_t)nblks,
2387 (u_longlong_t)tx->tx_txg);
2388 mutex_exit(&dn->dn_mtx);
2390 dbuf_free_range(dn, blkid, blkid + nblks - 1, tx);
2391 dnode_setdirty(dn, tx);
2395 dnode_spill_freed(dnode_t *dn)
2399 mutex_enter(&dn->dn_mtx);
2400 for (i = 0; i < TXG_SIZE; i++) {
2401 if (dn->dn_rm_spillblk[i] == DN_KILL_SPILLBLK)
2404 mutex_exit(&dn->dn_mtx);
2405 return (i < TXG_SIZE);
2408 /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */
2410 dnode_block_freed(dnode_t *dn, uint64_t blkid)
2414 if (blkid == DMU_BONUS_BLKID)
2417 if (dn->dn_free_txg)
2420 if (blkid == DMU_SPILL_BLKID)
2421 return (dnode_spill_freed(dn));
2423 mutex_enter(&dn->dn_mtx);
2424 for (i = 0; i < TXG_SIZE; i++) {
2425 if (dn->dn_free_ranges[i] != NULL &&
2426 range_tree_contains(dn->dn_free_ranges[i], blkid, 1))
2429 mutex_exit(&dn->dn_mtx);
2430 return (i < TXG_SIZE);
2433 /* call from syncing context when we actually write/free space for this dnode */
2435 dnode_diduse_space(dnode_t *dn, int64_t delta)
2438 dprintf_dnode(dn, "dn=%p dnp=%p used=%llu delta=%lld\n",
2440 (u_longlong_t)dn->dn_phys->dn_used,
2443 mutex_enter(&dn->dn_mtx);
2444 space = DN_USED_BYTES(dn->dn_phys);
2446 ASSERT3U(space + delta, >=, space); /* no overflow */
2448 ASSERT3U(space, >=, -delta); /* no underflow */
2451 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_DNODE_BYTES) {
2452 ASSERT((dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES) == 0);
2453 ASSERT0(P2PHASE(space, 1<<DEV_BSHIFT));
2454 dn->dn_phys->dn_used = space >> DEV_BSHIFT;
2456 dn->dn_phys->dn_used = space;
2457 dn->dn_phys->dn_flags |= DNODE_FLAG_USED_BYTES;
2459 mutex_exit(&dn->dn_mtx);
2463 * Scans a block at the indicated "level" looking for a hole or data,
2464 * depending on 'flags'.
2466 * If level > 0, then we are scanning an indirect block looking at its
2467 * pointers. If level == 0, then we are looking at a block of dnodes.
2469 * If we don't find what we are looking for in the block, we return ESRCH.
2470 * Otherwise, return with *offset pointing to the beginning (if searching
2471 * forwards) or end (if searching backwards) of the range covered by the
2472 * block pointer we matched on (or dnode).
2474 * The basic search algorithm used below by dnode_next_offset() is to
2475 * use this function to search up the block tree (widen the search) until
2476 * we find something (i.e., we don't return ESRCH) and then search back
2477 * down the tree (narrow the search) until we reach our original search
2481 dnode_next_offset_level(dnode_t *dn, int flags, uint64_t *offset,
2482 int lvl, uint64_t blkfill, uint64_t txg)
2484 dmu_buf_impl_t *db = NULL;
2486 uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT;
2487 uint64_t epb = 1ULL << epbs;
2488 uint64_t minfill, maxfill;
2490 int i, inc, error, span;
2492 ASSERT(RW_LOCK_HELD(&dn->dn_struct_rwlock));
2494 hole = ((flags & DNODE_FIND_HOLE) != 0);
2495 inc = (flags & DNODE_FIND_BACKWARDS) ? -1 : 1;
2496 ASSERT(txg == 0 || !hole);
2498 if (lvl == dn->dn_phys->dn_nlevels) {
2500 epb = dn->dn_phys->dn_nblkptr;
2501 data = dn->dn_phys->dn_blkptr;
2503 uint64_t blkid = dbuf_whichblock(dn, lvl, *offset);
2504 error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FALSE, FTAG, &db);
2506 if (error != ENOENT)
2511 * This can only happen when we are searching up
2512 * the block tree for data. We don't really need to
2513 * adjust the offset, as we will just end up looking
2514 * at the pointer to this block in its parent, and its
2515 * going to be unallocated, so we will skip over it.
2517 return (SET_ERROR(ESRCH));
2519 error = dbuf_read(db, NULL,
2520 DB_RF_CANFAIL | DB_RF_HAVESTRUCT |
2521 DB_RF_NO_DECRYPT | DB_RF_NOPREFETCH);
2523 dbuf_rele(db, FTAG);
2526 data = db->db.db_data;
2527 rw_enter(&db->db_rwlock, RW_READER);
2530 if (db != NULL && txg != 0 && (db->db_blkptr == NULL ||
2531 db->db_blkptr->blk_birth <= txg ||
2532 BP_IS_HOLE(db->db_blkptr))) {
2534 * This can only happen when we are searching up the tree
2535 * and these conditions mean that we need to keep climbing.
2537 error = SET_ERROR(ESRCH);
2538 } else if (lvl == 0) {
2539 dnode_phys_t *dnp = data;
2541 ASSERT(dn->dn_type == DMU_OT_DNODE);
2542 ASSERT(!(flags & DNODE_FIND_BACKWARDS));
2544 for (i = (*offset >> DNODE_SHIFT) & (blkfill - 1);
2545 i < blkfill; i += dnp[i].dn_extra_slots + 1) {
2546 if ((dnp[i].dn_type == DMU_OT_NONE) == hole)
2551 error = SET_ERROR(ESRCH);
2553 *offset = (*offset & ~(DNODE_BLOCK_SIZE - 1)) +
2556 blkptr_t *bp = data;
2557 uint64_t start = *offset;
2558 span = (lvl - 1) * epbs + dn->dn_datablkshift;
2560 maxfill = blkfill << ((lvl - 1) * epbs);
2567 if (span >= 8 * sizeof (*offset)) {
2568 /* This only happens on the highest indirection level */
2569 ASSERT3U((lvl - 1), ==, dn->dn_phys->dn_nlevels - 1);
2572 *offset = *offset >> span;
2575 for (i = BF64_GET(*offset, 0, epbs);
2576 i >= 0 && i < epb; i += inc) {
2577 if (BP_GET_FILL(&bp[i]) >= minfill &&
2578 BP_GET_FILL(&bp[i]) <= maxfill &&
2579 (hole || bp[i].blk_birth > txg))
2581 if (inc > 0 || *offset > 0)
2585 if (span >= 8 * sizeof (*offset)) {
2588 *offset = *offset << span;
2592 /* traversing backwards; position offset at the end */
2593 if (span < 8 * sizeof (*offset))
2594 *offset = MIN(*offset + (1ULL << span) - 1,
2596 } else if (*offset < start) {
2599 if (i < 0 || i >= epb)
2600 error = SET_ERROR(ESRCH);
2604 rw_exit(&db->db_rwlock);
2605 dbuf_rele(db, FTAG);
2612 * Find the next hole, data, or sparse region at or after *offset.
2613 * The value 'blkfill' tells us how many items we expect to find
2614 * in an L0 data block; this value is 1 for normal objects,
2615 * DNODES_PER_BLOCK for the meta dnode, and some fraction of
2616 * DNODES_PER_BLOCK when searching for sparse regions thereof.
2620 * dnode_next_offset(dn, flags, offset, 1, 1, 0);
2621 * Finds the next/previous hole/data in a file.
2622 * Used in dmu_offset_next().
2624 * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg);
2625 * Finds the next free/allocated dnode an objset's meta-dnode.
2626 * Only finds objects that have new contents since txg (ie.
2627 * bonus buffer changes and content removal are ignored).
2628 * Used in dmu_object_next().
2630 * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0);
2631 * Finds the next L2 meta-dnode bp that's at most 1/4 full.
2632 * Used in dmu_object_alloc().
2635 dnode_next_offset(dnode_t *dn, int flags, uint64_t *offset,
2636 int minlvl, uint64_t blkfill, uint64_t txg)
2638 uint64_t initial_offset = *offset;
2642 if (!(flags & DNODE_FIND_HAVELOCK))
2643 rw_enter(&dn->dn_struct_rwlock, RW_READER);
2645 if (dn->dn_phys->dn_nlevels == 0) {
2646 error = SET_ERROR(ESRCH);
2650 if (dn->dn_datablkshift == 0) {
2651 if (*offset < dn->dn_datablksz) {
2652 if (flags & DNODE_FIND_HOLE)
2653 *offset = dn->dn_datablksz;
2655 error = SET_ERROR(ESRCH);
2660 maxlvl = dn->dn_phys->dn_nlevels;
2662 for (lvl = minlvl; lvl <= maxlvl; lvl++) {
2663 error = dnode_next_offset_level(dn,
2664 flags, offset, lvl, blkfill, txg);
2669 while (error == 0 && --lvl >= minlvl) {
2670 error = dnode_next_offset_level(dn,
2671 flags, offset, lvl, blkfill, txg);
2675 * There's always a "virtual hole" at the end of the object, even
2676 * if all BP's which physically exist are non-holes.
2678 if ((flags & DNODE_FIND_HOLE) && error == ESRCH && txg == 0 &&
2679 minlvl == 1 && blkfill == 1 && !(flags & DNODE_FIND_BACKWARDS)) {
2683 if (error == 0 && (flags & DNODE_FIND_BACKWARDS ?
2684 initial_offset < *offset : initial_offset > *offset))
2685 error = SET_ERROR(ESRCH);
2687 if (!(flags & DNODE_FIND_HAVELOCK))
2688 rw_exit(&dn->dn_struct_rwlock);
2693 #if defined(_KERNEL)
2694 EXPORT_SYMBOL(dnode_hold);
2695 EXPORT_SYMBOL(dnode_rele);
2696 EXPORT_SYMBOL(dnode_set_nlevels);
2697 EXPORT_SYMBOL(dnode_set_blksz);
2698 EXPORT_SYMBOL(dnode_free_range);
2699 EXPORT_SYMBOL(dnode_evict_dbufs);
2700 EXPORT_SYMBOL(dnode_evict_bonus);
2703 ZFS_MODULE_PARAM(zfs, zfs_, default_bs, INT, ZMOD_RW,
2704 "Default dnode block shift");
2705 ZFS_MODULE_PARAM(zfs, zfs_, default_ibs, INT, ZMOD_RW,
2706 "Default dnode indirect block shift");