1 // SPDX-License-Identifier: CDDL-1.0
2 /*
3 * CDDL HEADER START
4 *
5 * The contents of this file are subject to the terms of the
6 * Common Development and Distribution License (the "License").
7 * You may not use this file except in compliance with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or https://opensource.org/licenses/CDDL-1.0.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /*
23 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Copyright (c) 2011, 2020 by Delphix. All rights reserved.
25 * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
26 * Copyright (c) 2013, Joyent, Inc. All rights reserved.
27 * Copyright (c) 2016, Nexenta Systems, Inc. All rights reserved.
28 * Copyright (c) 2015 by Chunwei Chen. All rights reserved.
29 * Copyright (c) 2019 Datto Inc.
30 * Copyright (c) 2019, 2023, Klara Inc.
31 * Copyright (c) 2019, Allan Jude
32 * Copyright (c) 2022 Hewlett Packard Enterprise Development LP.
33 * Copyright (c) 2021, 2022 by Pawel Jakub Dawidek
34 */
35
36 #include <sys/dmu.h>
37 #include <sys/dmu_impl.h>
38 #include <sys/dmu_tx.h>
39 #include <sys/dbuf.h>
40 #include <sys/dnode.h>
41 #include <sys/zfs_context.h>
42 #include <sys/dmu_objset.h>
43 #include <sys/dmu_traverse.h>
44 #include <sys/dsl_dataset.h>
45 #include <sys/dsl_dir.h>
46 #include <sys/dsl_pool.h>
47 #include <sys/dsl_synctask.h>
48 #include <sys/dsl_prop.h>
49 #include <sys/dmu_zfetch.h>
50 #include <sys/zfs_ioctl.h>
51 #include <sys/zap.h>
52 #include <sys/zio_checksum.h>
53 #include <sys/zio_compress.h>
54 #include <sys/sa.h>
55 #include <sys/zfeature.h>
56 #include <sys/abd.h>
57 #include <sys/brt.h>
58 #include <sys/trace_zfs.h>
59 #include <sys/zfs_racct.h>
60 #include <sys/zfs_rlock.h>
61 #ifdef _KERNEL
62 #include <sys/vmsystm.h>
63 #include <sys/zfs_znode.h>
64 #endif
65
66 /*
67 * Enable/disable nopwrite feature.
68 */
69 static int zfs_nopwrite_enabled = 1;
70
71 /*
72 * Tunable to control percentage of dirtied L1 blocks from frees allowed into
73 * one TXG. After this threshold is crossed, additional dirty blocks from frees
74 * will wait until the next TXG.
75 * A value of zero will disable this throttle.
76 */
77 static uint_t zfs_per_txg_dirty_frees_percent = 30;
78
79 /*
80 * Enable/disable forcing txg sync when dirty checking for holes with lseek().
81 * By default this is enabled to ensure accurate hole reporting, it can result
82 * in a significant performance penalty for lseek(SEEK_HOLE) heavy workloads.
83 * Disabling this option will result in holes never being reported in dirty
84 * files which is always safe.
85 */
86 static int zfs_dmu_offset_next_sync = 1;
87
88 /*
89 * Limit the amount we can prefetch with one call to this amount. This
90 * helps to limit the amount of memory that can be used by prefetching.
91 * Larger objects should be prefetched a bit at a time.
92 */
93 #ifdef _ILP32
94 uint_t dmu_prefetch_max = 8 * 1024 * 1024;
95 #else
96 uint_t dmu_prefetch_max = 8 * SPA_MAXBLOCKSIZE;
97 #endif
98
99 /*
100 * Override copies= for dedup state objects. 0 means the traditional behaviour
101 * (ie the default for the containing objset ie 3 for the MOS).
102 */
103 uint_t dmu_ddt_copies = 0;
104
105 const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES] = {
106 {DMU_BSWAP_UINT8, TRUE, FALSE, FALSE, "unallocated" },
107 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "object directory" },
108 {DMU_BSWAP_UINT64, TRUE, TRUE, FALSE, "object array" },
109 {DMU_BSWAP_UINT8, TRUE, FALSE, FALSE, "packed nvlist" },
110 {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "packed nvlist size" },
111 {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "bpobj" },
112 {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "bpobj header" },
113 {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "SPA space map header" },
114 {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "SPA space map" },
115 {DMU_BSWAP_UINT64, TRUE, FALSE, TRUE, "ZIL intent log" },
116 {DMU_BSWAP_DNODE, TRUE, FALSE, TRUE, "DMU dnode" },
117 {DMU_BSWAP_OBJSET, TRUE, TRUE, FALSE, "DMU objset" },
118 {DMU_BSWAP_UINT64, TRUE, TRUE, FALSE, "DSL directory" },
119 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL directory child map"},
120 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL dataset snap map" },
121 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL props" },
122 {DMU_BSWAP_UINT64, TRUE, TRUE, FALSE, "DSL dataset" },
123 {DMU_BSWAP_ZNODE, TRUE, FALSE, FALSE, "ZFS znode" },
124 {DMU_BSWAP_OLDACL, TRUE, FALSE, TRUE, "ZFS V0 ACL" },
125 {DMU_BSWAP_UINT8, FALSE, FALSE, TRUE, "ZFS plain file" },
126 {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "ZFS directory" },
127 {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "ZFS master node" },
128 {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "ZFS delete queue" },
129 {DMU_BSWAP_UINT8, FALSE, FALSE, TRUE, "zvol object" },
130 {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "zvol prop" },
131 {DMU_BSWAP_UINT8, FALSE, FALSE, TRUE, "other uint8[]" },
132 {DMU_BSWAP_UINT64, FALSE, FALSE, TRUE, "other uint64[]" },
133 {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "other ZAP" },
134 {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "persistent error log" },
135 {DMU_BSWAP_UINT8, TRUE, FALSE, FALSE, "SPA history" },
136 {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "SPA history offsets" },
137 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "Pool properties" },
138 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL permissions" },
139 {DMU_BSWAP_ACL, TRUE, FALSE, TRUE, "ZFS ACL" },
140 {DMU_BSWAP_UINT8, TRUE, FALSE, TRUE, "ZFS SYSACL" },
141 {DMU_BSWAP_UINT8, TRUE, FALSE, TRUE, "FUID table" },
142 {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "FUID table size" },
143 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL dataset next clones"},
144 {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "scan work queue" },
145 {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "ZFS user/group/project used" },
146 {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "ZFS user/group/project quota"},
147 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "snapshot refcount tags"},
148 {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "DDT ZAP algorithm" },
149 {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "DDT statistics" },
150 {DMU_BSWAP_UINT8, TRUE, FALSE, TRUE, "System attributes" },
151 {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "SA master node" },
152 {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "SA attr registration" },
153 {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "SA attr layouts" },
154 {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "scan translations" },
155 {DMU_BSWAP_UINT8, FALSE, FALSE, TRUE, "deduplicated block" },
156 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL deadlist map" },
157 {DMU_BSWAP_UINT64, TRUE, TRUE, FALSE, "DSL deadlist map hdr" },
158 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL dir clones" },
159 {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "bpobj subobj" }
160 };
161
162 dmu_object_byteswap_info_t dmu_ot_byteswap[DMU_BSWAP_NUMFUNCS] = {
163 { byteswap_uint8_array, "uint8" },
164 { byteswap_uint16_array, "uint16" },
165 { byteswap_uint32_array, "uint32" },
166 { byteswap_uint64_array, "uint64" },
167 { zap_byteswap, "zap" },
168 { dnode_buf_byteswap, "dnode" },
169 { dmu_objset_byteswap, "objset" },
170 { zfs_znode_byteswap, "znode" },
171 { zfs_oldacl_byteswap, "oldacl" },
172 { zfs_acl_byteswap, "acl" }
173 };
174
175 int
dmu_buf_hold_noread_by_dnode(dnode_t * dn,uint64_t offset,const void * tag,dmu_buf_t ** dbp)176 dmu_buf_hold_noread_by_dnode(dnode_t *dn, uint64_t offset,
177 const void *tag, dmu_buf_t **dbp)
178 {
179 uint64_t blkid;
180 dmu_buf_impl_t *db;
181
182 rw_enter(&dn->dn_struct_rwlock, RW_READER);
183 blkid = dbuf_whichblock(dn, 0, offset);
184 db = dbuf_hold(dn, blkid, tag);
185 rw_exit(&dn->dn_struct_rwlock);
186
187 if (db == NULL) {
188 *dbp = NULL;
189 return (SET_ERROR(EIO));
190 }
191
192 *dbp = &db->db;
193 return (0);
194 }
195
196 int
dmu_buf_hold_noread(objset_t * os,uint64_t object,uint64_t offset,const void * tag,dmu_buf_t ** dbp)197 dmu_buf_hold_noread(objset_t *os, uint64_t object, uint64_t offset,
198 const void *tag, dmu_buf_t **dbp)
199 {
200 dnode_t *dn;
201 uint64_t blkid;
202 dmu_buf_impl_t *db;
203 int err;
204
205 err = dnode_hold(os, object, FTAG, &dn);
206 if (err)
207 return (err);
208 rw_enter(&dn->dn_struct_rwlock, RW_READER);
209 blkid = dbuf_whichblock(dn, 0, offset);
210 db = dbuf_hold(dn, blkid, tag);
211 rw_exit(&dn->dn_struct_rwlock);
212 dnode_rele(dn, FTAG);
213
214 if (db == NULL) {
215 *dbp = NULL;
216 return (SET_ERROR(EIO));
217 }
218
219 *dbp = &db->db;
220 return (err);
221 }
222
223 int
dmu_buf_hold_by_dnode(dnode_t * dn,uint64_t offset,const void * tag,dmu_buf_t ** dbp,dmu_flags_t flags)224 dmu_buf_hold_by_dnode(dnode_t *dn, uint64_t offset,
225 const void *tag, dmu_buf_t **dbp, dmu_flags_t flags)
226 {
227 int err;
228
229 err = dmu_buf_hold_noread_by_dnode(dn, offset, tag, dbp);
230 if (err == 0) {
231 dmu_buf_impl_t *db = (dmu_buf_impl_t *)(*dbp);
232 err = dbuf_read(db, NULL, flags | DB_RF_CANFAIL);
233 if (err != 0) {
234 dbuf_rele(db, tag);
235 *dbp = NULL;
236 }
237 }
238
239 return (err);
240 }
241
242 int
dmu_buf_hold(objset_t * os,uint64_t object,uint64_t offset,const void * tag,dmu_buf_t ** dbp,dmu_flags_t flags)243 dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset,
244 const void *tag, dmu_buf_t **dbp, dmu_flags_t flags)
245 {
246 int err;
247
248 err = dmu_buf_hold_noread(os, object, offset, tag, dbp);
249 if (err == 0) {
250 dmu_buf_impl_t *db = (dmu_buf_impl_t *)(*dbp);
251 err = dbuf_read(db, NULL, flags | DB_RF_CANFAIL);
252 if (err != 0) {
253 dbuf_rele(db, tag);
254 *dbp = NULL;
255 }
256 }
257
258 return (err);
259 }
260
261 int
dmu_bonus_max(void)262 dmu_bonus_max(void)
263 {
264 return (DN_OLD_MAX_BONUSLEN);
265 }
266
267 int
dmu_set_bonus(dmu_buf_t * db_fake,int newsize,dmu_tx_t * tx)268 dmu_set_bonus(dmu_buf_t *db_fake, int newsize, dmu_tx_t *tx)
269 {
270 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
271 dnode_t *dn;
272 int error;
273
274 if (newsize < 0 || newsize > db_fake->db_size)
275 return (SET_ERROR(EINVAL));
276
277 DB_DNODE_ENTER(db);
278 dn = DB_DNODE(db);
279
280 if (dn->dn_bonus != db) {
281 error = SET_ERROR(EINVAL);
282 } else {
283 dnode_setbonuslen(dn, newsize, tx);
284 error = 0;
285 }
286
287 DB_DNODE_EXIT(db);
288 return (error);
289 }
290
291 int
dmu_set_bonustype(dmu_buf_t * db_fake,dmu_object_type_t type,dmu_tx_t * tx)292 dmu_set_bonustype(dmu_buf_t *db_fake, dmu_object_type_t type, dmu_tx_t *tx)
293 {
294 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
295 dnode_t *dn;
296 int error;
297
298 if (!DMU_OT_IS_VALID(type))
299 return (SET_ERROR(EINVAL));
300
301 DB_DNODE_ENTER(db);
302 dn = DB_DNODE(db);
303
304 if (dn->dn_bonus != db) {
305 error = SET_ERROR(EINVAL);
306 } else {
307 dnode_setbonus_type(dn, type, tx);
308 error = 0;
309 }
310
311 DB_DNODE_EXIT(db);
312 return (error);
313 }
314
315 dmu_object_type_t
dmu_get_bonustype(dmu_buf_t * db_fake)316 dmu_get_bonustype(dmu_buf_t *db_fake)
317 {
318 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
319 dmu_object_type_t type;
320
321 DB_DNODE_ENTER(db);
322 type = DB_DNODE(db)->dn_bonustype;
323 DB_DNODE_EXIT(db);
324
325 return (type);
326 }
327
328 int
dmu_rm_spill(objset_t * os,uint64_t object,dmu_tx_t * tx)329 dmu_rm_spill(objset_t *os, uint64_t object, dmu_tx_t *tx)
330 {
331 dnode_t *dn;
332 int error;
333
334 error = dnode_hold(os, object, FTAG, &dn);
335 dbuf_rm_spill(dn, tx);
336 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
337 dnode_rm_spill(dn, tx);
338 rw_exit(&dn->dn_struct_rwlock);
339 dnode_rele(dn, FTAG);
340 return (error);
341 }
342
343 /*
344 * Lookup and hold the bonus buffer for the provided dnode. If the dnode
345 * has not yet been allocated a new bonus dbuf a will be allocated.
346 * Returns ENOENT, EIO, or 0.
347 */
dmu_bonus_hold_by_dnode(dnode_t * dn,const void * tag,dmu_buf_t ** dbp,dmu_flags_t flags)348 int dmu_bonus_hold_by_dnode(dnode_t *dn, const void *tag, dmu_buf_t **dbp,
349 dmu_flags_t flags)
350 {
351 dmu_buf_impl_t *db;
352 int error;
353
354 rw_enter(&dn->dn_struct_rwlock, RW_READER);
355 if (dn->dn_bonus == NULL) {
356 if (!rw_tryupgrade(&dn->dn_struct_rwlock)) {
357 rw_exit(&dn->dn_struct_rwlock);
358 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
359 }
360 if (dn->dn_bonus == NULL)
361 dbuf_create_bonus(dn);
362 }
363 db = dn->dn_bonus;
364
365 /* as long as the bonus buf is held, the dnode will be held */
366 if (zfs_refcount_add(&db->db_holds, tag) == 1) {
367 VERIFY(dnode_add_ref(dn, db));
368 atomic_inc_32(&dn->dn_dbufs_count);
369 }
370
371 /*
372 * Wait to drop dn_struct_rwlock until after adding the bonus dbuf's
373 * hold and incrementing the dbuf count to ensure that dnode_move() sees
374 * a dnode hold for every dbuf.
375 */
376 rw_exit(&dn->dn_struct_rwlock);
377
378 error = dbuf_read(db, NULL, flags | DB_RF_CANFAIL);
379 if (error) {
380 dnode_evict_bonus(dn);
381 dbuf_rele(db, tag);
382 *dbp = NULL;
383 return (error);
384 }
385
386 *dbp = &db->db;
387 return (0);
388 }
389
390 int
dmu_bonus_hold(objset_t * os,uint64_t object,const void * tag,dmu_buf_t ** dbp)391 dmu_bonus_hold(objset_t *os, uint64_t object, const void *tag, dmu_buf_t **dbp)
392 {
393 dnode_t *dn;
394 int error;
395
396 error = dnode_hold(os, object, FTAG, &dn);
397 if (error)
398 return (error);
399
400 error = dmu_bonus_hold_by_dnode(dn, tag, dbp, DMU_READ_NO_PREFETCH);
401 dnode_rele(dn, FTAG);
402
403 return (error);
404 }
405
406 /*
407 * returns ENOENT, EIO, or 0.
408 *
409 * This interface will allocate a blank spill dbuf when a spill blk
410 * doesn't already exist on the dnode.
411 *
412 * if you only want to find an already existing spill db, then
413 * dmu_spill_hold_existing() should be used.
414 */
415 int
dmu_spill_hold_by_dnode(dnode_t * dn,dmu_flags_t flags,const void * tag,dmu_buf_t ** dbp)416 dmu_spill_hold_by_dnode(dnode_t *dn, dmu_flags_t flags, const void *tag,
417 dmu_buf_t **dbp)
418 {
419 dmu_buf_impl_t *db = NULL;
420 int err;
421
422 if ((flags & DB_RF_HAVESTRUCT) == 0)
423 rw_enter(&dn->dn_struct_rwlock, RW_READER);
424
425 db = dbuf_hold(dn, DMU_SPILL_BLKID, tag);
426
427 if ((flags & DB_RF_HAVESTRUCT) == 0)
428 rw_exit(&dn->dn_struct_rwlock);
429
430 if (db == NULL) {
431 *dbp = NULL;
432 return (SET_ERROR(EIO));
433 }
434 err = dbuf_read(db, NULL, flags);
435 if (err == 0)
436 *dbp = &db->db;
437 else {
438 dbuf_rele(db, tag);
439 *dbp = NULL;
440 }
441 return (err);
442 }
443
444 int
dmu_spill_hold_existing(dmu_buf_t * bonus,const void * tag,dmu_buf_t ** dbp)445 dmu_spill_hold_existing(dmu_buf_t *bonus, const void *tag, dmu_buf_t **dbp)
446 {
447 dmu_buf_impl_t *db = (dmu_buf_impl_t *)bonus;
448 dnode_t *dn;
449 int err;
450
451 DB_DNODE_ENTER(db);
452 dn = DB_DNODE(db);
453
454 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_SA) {
455 err = SET_ERROR(EINVAL);
456 } else {
457 rw_enter(&dn->dn_struct_rwlock, RW_READER);
458
459 if (!dn->dn_have_spill) {
460 err = SET_ERROR(ENOENT);
461 } else {
462 err = dmu_spill_hold_by_dnode(dn,
463 DB_RF_HAVESTRUCT | DB_RF_CANFAIL, tag, dbp);
464 }
465
466 rw_exit(&dn->dn_struct_rwlock);
467 }
468
469 DB_DNODE_EXIT(db);
470 return (err);
471 }
472
473 int
dmu_spill_hold_by_bonus(dmu_buf_t * bonus,dmu_flags_t flags,const void * tag,dmu_buf_t ** dbp)474 dmu_spill_hold_by_bonus(dmu_buf_t *bonus, dmu_flags_t flags, const void *tag,
475 dmu_buf_t **dbp)
476 {
477 dmu_buf_impl_t *db = (dmu_buf_impl_t *)bonus;
478 int err;
479
480 DB_DNODE_ENTER(db);
481 err = dmu_spill_hold_by_dnode(DB_DNODE(db), flags, tag, dbp);
482 DB_DNODE_EXIT(db);
483
484 return (err);
485 }
486
487 /*
488 * Note: longer-term, we should modify all of the dmu_buf_*() interfaces
489 * to take a held dnode rather than <os, object> -- the lookup is wasteful,
490 * and can induce severe lock contention when writing to several files
491 * whose dnodes are in the same block.
492 */
493 int
dmu_buf_hold_array_by_dnode(dnode_t * dn,uint64_t offset,uint64_t length,boolean_t read,const void * tag,int * numbufsp,dmu_buf_t *** dbpp,dmu_flags_t flags)494 dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset, uint64_t length,
495 boolean_t read, const void *tag, int *numbufsp, dmu_buf_t ***dbpp,
496 dmu_flags_t flags)
497 {
498 dmu_buf_t **dbp;
499 zstream_t *zs = NULL;
500 uint64_t blkid, nblks, i;
501 dmu_flags_t dbuf_flags;
502 int err;
503 zio_t *zio = NULL;
504 boolean_t missed = B_FALSE;
505
506 ASSERT(!read || length <= DMU_MAX_ACCESS);
507
508 /*
509 * Note: We directly notify the prefetch code of this read, so that
510 * we can tell it about the multi-block read. dbuf_read() only knows
511 * about the one block it is accessing.
512 */
513 dbuf_flags = (flags & ~DMU_READ_PREFETCH) | DMU_READ_NO_PREFETCH |
514 DB_RF_CANFAIL | DB_RF_NEVERWAIT | DB_RF_HAVESTRUCT;
515
516 rw_enter(&dn->dn_struct_rwlock, RW_READER);
517 if (dn->dn_datablkshift) {
518 int blkshift = dn->dn_datablkshift;
519 nblks = (P2ROUNDUP(offset + length, 1ULL << blkshift) -
520 P2ALIGN_TYPED(offset, 1ULL << blkshift, uint64_t))
521 >> blkshift;
522 } else {
523 if (offset + length > dn->dn_datablksz) {
524 zfs_panic_recover("zfs: accessing past end of object "
525 "%llx/%llx (size=%u access=%llu+%llu)",
526 (longlong_t)dn->dn_objset->
527 os_dsl_dataset->ds_object,
528 (longlong_t)dn->dn_object, dn->dn_datablksz,
529 (longlong_t)offset, (longlong_t)length);
530 rw_exit(&dn->dn_struct_rwlock);
531 return (SET_ERROR(EIO));
532 }
533 nblks = 1;
534 }
535 dbp = kmem_zalloc(sizeof (dmu_buf_t *) * nblks, KM_SLEEP);
536
537 if (read)
538 zio = zio_root(dn->dn_objset->os_spa, NULL, NULL,
539 ZIO_FLAG_CANFAIL);
540 blkid = dbuf_whichblock(dn, 0, offset);
541 if ((flags & DMU_READ_NO_PREFETCH) == 0) {
542 /*
543 * Prepare the zfetch before initiating the demand reads, so
544 * that if multiple threads block on same indirect block, we
545 * base predictions on the original less racy request order.
546 */
547 zs = dmu_zfetch_prepare(&dn->dn_zfetch, blkid, nblks,
548 read && !(flags & DMU_DIRECTIO), B_TRUE);
549 }
550 for (i = 0; i < nblks; i++) {
551 dmu_buf_impl_t *db = dbuf_hold(dn, blkid + i, tag);
552 if (db == NULL) {
553 if (zs) {
554 dmu_zfetch_run(&dn->dn_zfetch, zs, missed,
555 B_TRUE, (flags & DMU_UNCACHEDIO));
556 }
557 rw_exit(&dn->dn_struct_rwlock);
558 dmu_buf_rele_array(dbp, nblks, tag);
559 if (read)
560 zio_nowait(zio);
561 return (SET_ERROR(EIO));
562 }
563
564 /*
565 * Initiate async demand data read.
566 * We check the db_state after calling dbuf_read() because
567 * (1) dbuf_read() may change the state to CACHED due to a
568 * hit in the ARC, and (2) on a cache miss, a child will
569 * have been added to "zio" but not yet completed, so the
570 * state will not yet be CACHED.
571 */
572 if (read) {
573 if (i == nblks - 1 && blkid + i < dn->dn_maxblkid &&
574 offset + length < db->db.db_offset +
575 db->db.db_size) {
576 if (offset <= db->db.db_offset)
577 dbuf_flags |= DMU_PARTIAL_FIRST;
578 else
579 dbuf_flags |= DMU_PARTIAL_MORE;
580 }
581 (void) dbuf_read(db, zio, dbuf_flags);
582 if (db->db_state != DB_CACHED)
583 missed = B_TRUE;
584 }
585 dbp[i] = &db->db;
586 }
587
588 /*
589 * If we are doing O_DIRECT we still hold the dbufs, even for reads,
590 * but we do not issue any reads here. We do not want to account for
591 * writes in this case.
592 *
593 * O_DIRECT write/read accounting takes place in
594 * dmu_{write/read}_abd().
595 */
596 if (!read && ((flags & DMU_DIRECTIO) == 0))
597 zfs_racct_write(dn->dn_objset->os_spa, length, nblks, flags);
598
599 if (zs) {
600 dmu_zfetch_run(&dn->dn_zfetch, zs, missed, B_TRUE,
601 (flags & DMU_UNCACHEDIO));
602 }
603 rw_exit(&dn->dn_struct_rwlock);
604
605 if (read) {
606 /* wait for async read i/o */
607 err = zio_wait(zio);
608 if (err) {
609 dmu_buf_rele_array(dbp, nblks, tag);
610 return (err);
611 }
612
613 /* wait for other io to complete */
614 for (i = 0; i < nblks; i++) {
615 dmu_buf_impl_t *db = (dmu_buf_impl_t *)dbp[i];
616 mutex_enter(&db->db_mtx);
617 while (db->db_state == DB_READ ||
618 db->db_state == DB_FILL)
619 cv_wait(&db->db_changed, &db->db_mtx);
620 if (db->db_state == DB_UNCACHED)
621 err = SET_ERROR(EIO);
622 mutex_exit(&db->db_mtx);
623 if (err) {
624 dmu_buf_rele_array(dbp, nblks, tag);
625 return (err);
626 }
627 }
628 }
629
630 *numbufsp = nblks;
631 *dbpp = dbp;
632 return (0);
633 }
634
635 int
dmu_buf_hold_array(objset_t * os,uint64_t object,uint64_t offset,uint64_t length,int read,const void * tag,int * numbufsp,dmu_buf_t *** dbpp,dmu_flags_t flags)636 dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset,
637 uint64_t length, int read, const void *tag, int *numbufsp,
638 dmu_buf_t ***dbpp, dmu_flags_t flags)
639 {
640 dnode_t *dn;
641 int err;
642
643 err = dnode_hold(os, object, FTAG, &dn);
644 if (err)
645 return (err);
646
647 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag,
648 numbufsp, dbpp, flags);
649
650 dnode_rele(dn, FTAG);
651
652 return (err);
653 }
654
655 int
dmu_buf_hold_array_by_bonus(dmu_buf_t * db_fake,uint64_t offset,uint64_t length,boolean_t read,const void * tag,int * numbufsp,dmu_buf_t *** dbpp,dmu_flags_t flags)656 dmu_buf_hold_array_by_bonus(dmu_buf_t *db_fake, uint64_t offset,
657 uint64_t length, boolean_t read, const void *tag, int *numbufsp,
658 dmu_buf_t ***dbpp, dmu_flags_t flags)
659 {
660 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
661 int err;
662
663 DB_DNODE_ENTER(db);
664 err = dmu_buf_hold_array_by_dnode(DB_DNODE(db), offset, length, read,
665 tag, numbufsp, dbpp, flags);
666 DB_DNODE_EXIT(db);
667
668 return (err);
669 }
670
671 void
dmu_buf_rele_array(dmu_buf_t ** dbp_fake,int numbufs,const void * tag)672 dmu_buf_rele_array(dmu_buf_t **dbp_fake, int numbufs, const void *tag)
673 {
674 int i;
675 dmu_buf_impl_t **dbp = (dmu_buf_impl_t **)dbp_fake;
676
677 if (numbufs == 0)
678 return;
679
680 for (i = 0; i < numbufs; i++) {
681 if (dbp[i])
682 dbuf_rele(dbp[i], tag);
683 }
684
685 kmem_free(dbp, sizeof (dmu_buf_t *) * numbufs);
686 }
687
688 /*
689 * Issue prefetch I/Os for the given blocks. If level is greater than 0, the
690 * indirect blocks prefetched will be those that point to the blocks containing
691 * the data starting at offset, and continuing to offset + len. If the range
692 * is too long, prefetch the first dmu_prefetch_max bytes as requested, while
693 * for the rest only a higher level, also fitting within dmu_prefetch_max. It
694 * should primarily help random reads, since for long sequential reads there is
695 * a speculative prefetcher.
696 *
697 * Note that if the indirect blocks above the blocks being prefetched are not
698 * in cache, they will be asynchronously read in. Dnode read by dnode_hold()
699 * is currently synchronous.
700 */
701 void
dmu_prefetch(objset_t * os,uint64_t object,int64_t level,uint64_t offset,uint64_t len,zio_priority_t pri)702 dmu_prefetch(objset_t *os, uint64_t object, int64_t level, uint64_t offset,
703 uint64_t len, zio_priority_t pri)
704 {
705 dnode_t *dn;
706
707 if (dmu_prefetch_max == 0 || len == 0) {
708 dmu_prefetch_dnode(os, object, pri);
709 return;
710 }
711
712 if (dnode_hold(os, object, FTAG, &dn) != 0)
713 return;
714
715 dmu_prefetch_by_dnode(dn, level, offset, len, pri);
716
717 dnode_rele(dn, FTAG);
718 }
719
720 void
dmu_prefetch_by_dnode(dnode_t * dn,int64_t level,uint64_t offset,uint64_t len,zio_priority_t pri)721 dmu_prefetch_by_dnode(dnode_t *dn, int64_t level, uint64_t offset,
722 uint64_t len, zio_priority_t pri)
723 {
724 int64_t level2 = level;
725 uint64_t start, end, start2, end2;
726
727 /*
728 * Depending on len we may do two prefetches: blocks [start, end) at
729 * level, and following blocks [start2, end2) at higher level2.
730 */
731 rw_enter(&dn->dn_struct_rwlock, RW_READER);
732 if (dn->dn_datablkshift != 0) {
733
734 /*
735 * Limit prefetch to present blocks.
736 */
737 uint64_t size = (dn->dn_maxblkid + 1) << dn->dn_datablkshift;
738 if (offset >= size) {
739 rw_exit(&dn->dn_struct_rwlock);
740 return;
741 }
742 if (offset + len < offset || offset + len > size)
743 len = size - offset;
744
745 /*
746 * The object has multiple blocks. Calculate the full range
747 * of blocks [start, end2) and then split it into two parts,
748 * so that the first [start, end) fits into dmu_prefetch_max.
749 */
750 start = dbuf_whichblock(dn, level, offset);
751 end2 = dbuf_whichblock(dn, level, offset + len - 1) + 1;
752 uint8_t ibs = dn->dn_indblkshift;
753 uint8_t bs = (level == 0) ? dn->dn_datablkshift : ibs;
754 uint_t limit = P2ROUNDUP(dmu_prefetch_max, 1 << bs) >> bs;
755 start2 = end = MIN(end2, start + limit);
756
757 /*
758 * Find level2 where [start2, end2) fits into dmu_prefetch_max.
759 */
760 uint8_t ibps = ibs - SPA_BLKPTRSHIFT;
761 limit = P2ROUNDUP(dmu_prefetch_max, 1 << ibs) >> ibs;
762 if (limit == 0)
763 end2 = start2;
764 do {
765 level2++;
766 start2 = P2ROUNDUP(start2, 1 << ibps) >> ibps;
767 end2 = P2ROUNDUP(end2, 1 << ibps) >> ibps;
768 } while (end2 - start2 > limit);
769 } else {
770 /* There is only one block. Prefetch it or nothing. */
771 start = start2 = end2 = 0;
772 end = start + (level == 0 && offset < dn->dn_datablksz);
773 }
774
775 for (uint64_t i = start; i < end; i++)
776 dbuf_prefetch(dn, level, i, pri, 0);
777 for (uint64_t i = start2; i < end2; i++)
778 dbuf_prefetch(dn, level2, i, pri, 0);
779 rw_exit(&dn->dn_struct_rwlock);
780 }
781
782 typedef struct {
783 kmutex_t dpa_lock;
784 kcondvar_t dpa_cv;
785 uint64_t dpa_pending_io;
786 } dmu_prefetch_arg_t;
787
788 static void
dmu_prefetch_done(void * arg,uint64_t level,uint64_t blkid,boolean_t issued)789 dmu_prefetch_done(void *arg, uint64_t level, uint64_t blkid, boolean_t issued)
790 {
791 (void) level; (void) blkid; (void)issued;
792 dmu_prefetch_arg_t *dpa = arg;
793
794 ASSERT0(level);
795
796 mutex_enter(&dpa->dpa_lock);
797 ASSERT3U(dpa->dpa_pending_io, >, 0);
798 if (--dpa->dpa_pending_io == 0)
799 cv_broadcast(&dpa->dpa_cv);
800 mutex_exit(&dpa->dpa_lock);
801 }
802
803 static void
dmu_prefetch_wait_by_dnode(dnode_t * dn,uint64_t offset,uint64_t len)804 dmu_prefetch_wait_by_dnode(dnode_t *dn, uint64_t offset, uint64_t len)
805 {
806 dmu_prefetch_arg_t dpa;
807
808 mutex_init(&dpa.dpa_lock, NULL, MUTEX_DEFAULT, NULL);
809 cv_init(&dpa.dpa_cv, NULL, CV_DEFAULT, NULL);
810
811 rw_enter(&dn->dn_struct_rwlock, RW_READER);
812
813 uint64_t start = dbuf_whichblock(dn, 0, offset);
814 uint64_t end = dbuf_whichblock(dn, 0, offset + len - 1) + 1;
815 dpa.dpa_pending_io = end - start;
816
817 for (uint64_t blk = start; blk < end; blk++) {
818 (void) dbuf_prefetch_impl(dn, 0, blk, ZIO_PRIORITY_ASYNC_READ,
819 0, dmu_prefetch_done, &dpa);
820 }
821
822 rw_exit(&dn->dn_struct_rwlock);
823
824 /* wait for prefetch L0 reads to finish */
825 mutex_enter(&dpa.dpa_lock);
826 while (dpa.dpa_pending_io > 0) {
827 cv_wait(&dpa.dpa_cv, &dpa.dpa_lock);
828
829 }
830 mutex_exit(&dpa.dpa_lock);
831
832 mutex_destroy(&dpa.dpa_lock);
833 cv_destroy(&dpa.dpa_cv);
834 }
835
836 /*
837 * Issue prefetch I/Os for the given L0 block range and wait for the I/O
838 * to complete. This does not enforce dmu_prefetch_max and will prefetch
839 * the entire range. The blocks are read from disk into the ARC but no
840 * decompression occurs (i.e., the dbuf cache is not required).
841 */
842 int
dmu_prefetch_wait(objset_t * os,uint64_t object,uint64_t offset,uint64_t size)843 dmu_prefetch_wait(objset_t *os, uint64_t object, uint64_t offset, uint64_t size)
844 {
845 dnode_t *dn;
846 int err = 0;
847
848 err = dnode_hold(os, object, FTAG, &dn);
849 if (err != 0)
850 return (err);
851
852 /*
853 * Chunk the requests (16 indirects worth) so that we can be
854 * interrupted. Prefetch at least SPA_MAXBLOCKSIZE at a time
855 * to better utilize pools with smaller block sizes.
856 */
857 uint64_t chunksize;
858 if (dn->dn_indblkshift) {
859 uint64_t nbps = bp_span_in_blocks(dn->dn_indblkshift, 1);
860 chunksize = (nbps * 16) << dn->dn_datablkshift;
861 chunksize = MAX(chunksize, SPA_MAXBLOCKSIZE);
862 } else {
863 chunksize = dn->dn_datablksz;
864 }
865
866 while (size > 0) {
867 uint64_t mylen = MIN(size, chunksize);
868
869 dmu_prefetch_wait_by_dnode(dn, offset, mylen);
870
871 offset += mylen;
872 size -= mylen;
873
874 if (issig()) {
875 err = SET_ERROR(EINTR);
876 break;
877 }
878 }
879
880 dnode_rele(dn, FTAG);
881
882 return (err);
883 }
884
885 /*
886 * Issue prefetch I/Os for the given object's dnode.
887 */
888 void
dmu_prefetch_dnode(objset_t * os,uint64_t object,zio_priority_t pri)889 dmu_prefetch_dnode(objset_t *os, uint64_t object, zio_priority_t pri)
890 {
891 if (object == 0 || object >= DN_MAX_OBJECT)
892 return;
893
894 dnode_t *dn = DMU_META_DNODE(os);
895 rw_enter(&dn->dn_struct_rwlock, RW_READER);
896 uint64_t blkid = dbuf_whichblock(dn, 0, object * sizeof (dnode_phys_t));
897 dbuf_prefetch(dn, 0, blkid, pri, 0);
898 rw_exit(&dn->dn_struct_rwlock);
899 }
900
901 /*
902 * Get the next "chunk" of file data to free. We traverse the file from
903 * the end so that the file gets shorter over time (if we crash in the
904 * middle, this will leave us in a better state). We find allocated file
905 * data by simply searching the allocated level 1 indirects.
906 *
907 * On input, *start should be the first offset that does not need to be
908 * freed (e.g. "offset + length"). On return, *start will be the first
909 * offset that should be freed and l1blks is set to the number of level 1
910 * indirect blocks found within the chunk.
911 */
912 static int
get_next_chunk(dnode_t * dn,uint64_t * start,uint64_t minimum,uint64_t * l1blks)913 get_next_chunk(dnode_t *dn, uint64_t *start, uint64_t minimum, uint64_t *l1blks)
914 {
915 uint64_t blks;
916 uint64_t maxblks = DMU_MAX_ACCESS >> (dn->dn_indblkshift + 1);
917 /* bytes of data covered by a level-1 indirect block */
918 uint64_t iblkrange = (uint64_t)dn->dn_datablksz *
919 EPB(dn->dn_indblkshift, SPA_BLKPTRSHIFT);
920
921 ASSERT3U(minimum, <=, *start);
922
923 /* dn_nlevels == 1 means we don't have any L1 blocks */
924 if (dn->dn_nlevels <= 1) {
925 *l1blks = 0;
926 *start = minimum;
927 return (0);
928 }
929
930 /*
931 * Check if we can free the entire range assuming that all of the
932 * L1 blocks in this range have data. If we can, we use this
933 * worst case value as an estimate so we can avoid having to look
934 * at the object's actual data.
935 */
936 uint64_t total_l1blks =
937 (roundup(*start, iblkrange) - (minimum / iblkrange * iblkrange)) /
938 iblkrange;
939 if (total_l1blks <= maxblks) {
940 *l1blks = total_l1blks;
941 *start = minimum;
942 return (0);
943 }
944 ASSERT(ISP2(iblkrange));
945
946 for (blks = 0; *start > minimum && blks < maxblks; blks++) {
947 int err;
948
949 /*
950 * dnode_next_offset(BACKWARDS) will find an allocated L1
951 * indirect block at or before the input offset. We must
952 * decrement *start so that it is at the end of the region
953 * to search.
954 */
955 (*start)--;
956
957 err = dnode_next_offset(dn,
958 DNODE_FIND_BACKWARDS, start, 2, 1, 0);
959
960 /* if there are no indirect blocks before start, we are done */
961 if (err == ESRCH) {
962 *start = minimum;
963 break;
964 } else if (err != 0) {
965 *l1blks = blks;
966 return (err);
967 }
968
969 /* set start to the beginning of this L1 indirect */
970 *start = P2ALIGN_TYPED(*start, iblkrange, uint64_t);
971 }
972 if (*start < minimum)
973 *start = minimum;
974 *l1blks = blks;
975
976 return (0);
977 }
978
979 /*
980 * If this objset is of type OST_ZFS return true if vfs's unmounted flag is set,
981 * otherwise return false.
982 * Used below in dmu_free_long_range_impl() to enable abort when unmounting
983 */
984 static boolean_t
dmu_objset_zfs_unmounting(objset_t * os)985 dmu_objset_zfs_unmounting(objset_t *os)
986 {
987 #ifdef _KERNEL
988 if (dmu_objset_type(os) == DMU_OST_ZFS)
989 return (zfs_get_vfs_flag_unmounted(os));
990 #else
991 (void) os;
992 #endif
993 return (B_FALSE);
994 }
995
996 static int
dmu_free_long_range_impl(objset_t * os,dnode_t * dn,uint64_t offset,uint64_t length)997 dmu_free_long_range_impl(objset_t *os, dnode_t *dn, uint64_t offset,
998 uint64_t length)
999 {
1000 uint64_t object_size;
1001 int err;
1002 uint64_t dirty_frees_threshold;
1003 dsl_pool_t *dp = dmu_objset_pool(os);
1004
1005 if (dn == NULL)
1006 return (SET_ERROR(EINVAL));
1007
1008 object_size = (dn->dn_maxblkid + 1) * dn->dn_datablksz;
1009 if (offset >= object_size)
1010 return (0);
1011
1012 if (zfs_per_txg_dirty_frees_percent <= 100)
1013 dirty_frees_threshold =
1014 zfs_per_txg_dirty_frees_percent * zfs_dirty_data_max / 100;
1015 else
1016 dirty_frees_threshold = zfs_dirty_data_max / 20;
1017
1018 if (length == DMU_OBJECT_END || offset + length > object_size)
1019 length = object_size - offset;
1020
1021 while (length != 0) {
1022 uint64_t chunk_end, chunk_begin, chunk_len;
1023 uint64_t l1blks;
1024 dmu_tx_t *tx;
1025
1026 if (dmu_objset_zfs_unmounting(dn->dn_objset))
1027 return (SET_ERROR(EINTR));
1028
1029 chunk_end = chunk_begin = offset + length;
1030
1031 /* move chunk_begin backwards to the beginning of this chunk */
1032 err = get_next_chunk(dn, &chunk_begin, offset, &l1blks);
1033 if (err)
1034 return (err);
1035 ASSERT3U(chunk_begin, >=, offset);
1036 ASSERT3U(chunk_begin, <=, chunk_end);
1037
1038 chunk_len = chunk_end - chunk_begin;
1039
1040 tx = dmu_tx_create(os);
1041 dmu_tx_hold_free(tx, dn->dn_object, chunk_begin, chunk_len);
1042
1043 /*
1044 * Mark this transaction as typically resulting in a net
1045 * reduction in space used.
1046 */
1047 dmu_tx_mark_netfree(tx);
1048 err = dmu_tx_assign(tx, DMU_TX_WAIT);
1049 if (err) {
1050 dmu_tx_abort(tx);
1051 return (err);
1052 }
1053
1054 uint64_t txg = dmu_tx_get_txg(tx);
1055
1056 mutex_enter(&dp->dp_lock);
1057 uint64_t long_free_dirty =
1058 dp->dp_long_free_dirty_pertxg[txg & TXG_MASK];
1059 mutex_exit(&dp->dp_lock);
1060
1061 /*
1062 * To avoid filling up a TXG with just frees, wait for
1063 * the next TXG to open before freeing more chunks if
1064 * we have reached the threshold of frees.
1065 */
1066 if (dirty_frees_threshold != 0 &&
1067 long_free_dirty >= dirty_frees_threshold) {
1068 DMU_TX_STAT_BUMP(dmu_tx_dirty_frees_delay);
1069 dmu_tx_commit(tx);
1070 txg_wait_open(dp, 0, B_TRUE);
1071 continue;
1072 }
1073
1074 /*
1075 * In order to prevent unnecessary write throttling, for each
1076 * TXG, we track the cumulative size of L1 blocks being dirtied
1077 * in dnode_free_range() below. We compare this number to a
1078 * tunable threshold, past which we prevent new L1 dirty freeing
1079 * blocks from being added into the open TXG. See
1080 * dmu_free_long_range_impl() for details. The threshold
1081 * prevents write throttle activation due to dirty freeing L1
1082 * blocks taking up a large percentage of zfs_dirty_data_max.
1083 */
1084 mutex_enter(&dp->dp_lock);
1085 dp->dp_long_free_dirty_pertxg[txg & TXG_MASK] +=
1086 l1blks << dn->dn_indblkshift;
1087 mutex_exit(&dp->dp_lock);
1088 DTRACE_PROBE3(free__long__range,
1089 uint64_t, long_free_dirty, uint64_t, chunk_len,
1090 uint64_t, txg);
1091 dnode_free_range(dn, chunk_begin, chunk_len, tx);
1092
1093 dmu_tx_commit(tx);
1094
1095 length -= chunk_len;
1096 }
1097 return (0);
1098 }
1099
1100 int
dmu_free_long_range(objset_t * os,uint64_t object,uint64_t offset,uint64_t length)1101 dmu_free_long_range(objset_t *os, uint64_t object,
1102 uint64_t offset, uint64_t length)
1103 {
1104 dnode_t *dn;
1105 int err;
1106
1107 err = dnode_hold(os, object, FTAG, &dn);
1108 if (err != 0)
1109 return (err);
1110 err = dmu_free_long_range_impl(os, dn, offset, length);
1111
1112 /*
1113 * It is important to zero out the maxblkid when freeing the entire
1114 * file, so that (a) subsequent calls to dmu_free_long_range_impl()
1115 * will take the fast path, and (b) dnode_reallocate() can verify
1116 * that the entire file has been freed.
1117 */
1118 if (err == 0 && offset == 0 && length == DMU_OBJECT_END)
1119 dn->dn_maxblkid = 0;
1120
1121 dnode_rele(dn, FTAG);
1122 return (err);
1123 }
1124
1125 int
dmu_free_long_object(objset_t * os,uint64_t object)1126 dmu_free_long_object(objset_t *os, uint64_t object)
1127 {
1128 dmu_tx_t *tx;
1129 int err;
1130
1131 err = dmu_free_long_range(os, object, 0, DMU_OBJECT_END);
1132 if (err != 0)
1133 return (err);
1134
1135 tx = dmu_tx_create(os);
1136 dmu_tx_hold_bonus(tx, object);
1137 dmu_tx_hold_free(tx, object, 0, DMU_OBJECT_END);
1138 dmu_tx_mark_netfree(tx);
1139 err = dmu_tx_assign(tx, DMU_TX_WAIT);
1140 if (err == 0) {
1141 err = dmu_object_free(os, object, tx);
1142 dmu_tx_commit(tx);
1143 } else {
1144 dmu_tx_abort(tx);
1145 }
1146
1147 return (err);
1148 }
1149
1150 int
dmu_free_range(objset_t * os,uint64_t object,uint64_t offset,uint64_t size,dmu_tx_t * tx)1151 dmu_free_range(objset_t *os, uint64_t object, uint64_t offset,
1152 uint64_t size, dmu_tx_t *tx)
1153 {
1154 dnode_t *dn;
1155 int err = dnode_hold(os, object, FTAG, &dn);
1156 if (err)
1157 return (err);
1158 ASSERT(offset < UINT64_MAX);
1159 ASSERT(size == DMU_OBJECT_END || size <= UINT64_MAX - offset);
1160 dnode_free_range(dn, offset, size, tx);
1161 dnode_rele(dn, FTAG);
1162 return (0);
1163 }
1164
1165 static int
dmu_read_impl(dnode_t * dn,uint64_t offset,uint64_t size,void * buf,dmu_flags_t flags)1166 dmu_read_impl(dnode_t *dn, uint64_t offset, uint64_t size,
1167 void *buf, dmu_flags_t flags)
1168 {
1169 dmu_buf_t **dbp;
1170 int numbufs, err = 0;
1171
1172 /*
1173 * Deal with odd block sizes, where there can't be data past the first
1174 * block. If we ever do the tail block optimization, we will need to
1175 * handle that here as well.
1176 */
1177 if (dn->dn_maxblkid == 0) {
1178 uint64_t newsz = offset > dn->dn_datablksz ? 0 :
1179 MIN(size, dn->dn_datablksz - offset);
1180 memset((char *)buf + newsz, 0, size - newsz);
1181 size = newsz;
1182 }
1183
1184 if (size == 0)
1185 return (0);
1186
1187 /* Allow Direct I/O when requested and properly aligned */
1188 if ((flags & DMU_DIRECTIO) && zfs_dio_page_aligned(buf) &&
1189 zfs_dio_aligned(offset, size, PAGESIZE)) {
1190 abd_t *data = abd_get_from_buf(buf, size);
1191 err = dmu_read_abd(dn, offset, size, data, flags);
1192 abd_free(data);
1193 return (err);
1194 }
1195 flags &= ~DMU_DIRECTIO;
1196
1197 while (size > 0) {
1198 uint64_t mylen = MIN(size, DMU_MAX_ACCESS / 2);
1199 int i;
1200
1201 /*
1202 * NB: we could do this block-at-a-time, but it's nice
1203 * to be reading in parallel.
1204 */
1205 err = dmu_buf_hold_array_by_dnode(dn, offset, mylen,
1206 TRUE, FTAG, &numbufs, &dbp, flags);
1207 if (err)
1208 break;
1209
1210 for (i = 0; i < numbufs; i++) {
1211 uint64_t tocpy;
1212 int64_t bufoff;
1213 dmu_buf_t *db = dbp[i];
1214
1215 ASSERT(size > 0);
1216
1217 bufoff = offset - db->db_offset;
1218 tocpy = MIN(db->db_size - bufoff, size);
1219
1220 ASSERT(db->db_data != NULL);
1221 (void) memcpy(buf, (char *)db->db_data + bufoff, tocpy);
1222
1223 offset += tocpy;
1224 size -= tocpy;
1225 buf = (char *)buf + tocpy;
1226 }
1227 dmu_buf_rele_array(dbp, numbufs, FTAG);
1228 }
1229 return (err);
1230 }
1231
1232 int
dmu_read(objset_t * os,uint64_t object,uint64_t offset,uint64_t size,void * buf,dmu_flags_t flags)1233 dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
1234 void *buf, dmu_flags_t flags)
1235 {
1236 dnode_t *dn;
1237 int err;
1238
1239 err = dnode_hold(os, object, FTAG, &dn);
1240 if (err != 0)
1241 return (err);
1242
1243 err = dmu_read_impl(dn, offset, size, buf, flags);
1244 dnode_rele(dn, FTAG);
1245 return (err);
1246 }
1247
1248 int
dmu_read_by_dnode(dnode_t * dn,uint64_t offset,uint64_t size,void * buf,dmu_flags_t flags)1249 dmu_read_by_dnode(dnode_t *dn, uint64_t offset, uint64_t size, void *buf,
1250 dmu_flags_t flags)
1251 {
1252 return (dmu_read_impl(dn, offset, size, buf, flags));
1253 }
1254
1255 static void
dmu_write_impl(dmu_buf_t ** dbp,int numbufs,uint64_t offset,uint64_t size,const void * buf,dmu_tx_t * tx,dmu_flags_t flags)1256 dmu_write_impl(dmu_buf_t **dbp, int numbufs, uint64_t offset, uint64_t size,
1257 const void *buf, dmu_tx_t *tx, dmu_flags_t flags)
1258 {
1259 int i;
1260
1261 for (i = 0; i < numbufs; i++) {
1262 uint64_t tocpy;
1263 int64_t bufoff;
1264 dmu_buf_t *db = dbp[i];
1265
1266 ASSERT(size > 0);
1267
1268 bufoff = offset - db->db_offset;
1269 tocpy = MIN(db->db_size - bufoff, size);
1270
1271 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
1272
1273 if (tocpy == db->db_size) {
1274 dmu_buf_will_fill_flags(db, tx, B_FALSE, flags);
1275 } else {
1276 if (i == numbufs - 1 && bufoff + tocpy < db->db_size) {
1277 if (bufoff == 0)
1278 flags |= DMU_PARTIAL_FIRST;
1279 else
1280 flags |= DMU_PARTIAL_MORE;
1281 }
1282 dmu_buf_will_dirty_flags(db, tx, flags);
1283 }
1284
1285 ASSERT(db->db_data != NULL);
1286 (void) memcpy((char *)db->db_data + bufoff, buf, tocpy);
1287
1288 if (tocpy == db->db_size)
1289 dmu_buf_fill_done(db, tx, B_FALSE);
1290
1291 offset += tocpy;
1292 size -= tocpy;
1293 buf = (char *)buf + tocpy;
1294 }
1295 }
1296
1297 void
dmu_write(objset_t * os,uint64_t object,uint64_t offset,uint64_t size,const void * buf,dmu_tx_t * tx,dmu_flags_t flags)1298 dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
1299 const void *buf, dmu_tx_t *tx, dmu_flags_t flags)
1300 {
1301 dmu_buf_t **dbp;
1302 int numbufs;
1303
1304 if (size == 0)
1305 return;
1306
1307 VERIFY0(dmu_buf_hold_array(os, object, offset, size,
1308 FALSE, FTAG, &numbufs, &dbp, flags));
1309 dmu_write_impl(dbp, numbufs, offset, size, buf, tx, flags);
1310 dmu_buf_rele_array(dbp, numbufs, FTAG);
1311 }
1312
1313 int
dmu_write_by_dnode(dnode_t * dn,uint64_t offset,uint64_t size,const void * buf,dmu_tx_t * tx,dmu_flags_t flags)1314 dmu_write_by_dnode(dnode_t *dn, uint64_t offset, uint64_t size,
1315 const void *buf, dmu_tx_t *tx, dmu_flags_t flags)
1316 {
1317 dmu_buf_t **dbp;
1318 int numbufs;
1319 int error;
1320
1321 if (size == 0)
1322 return (0);
1323
1324 /* Allow Direct I/O when requested and properly aligned */
1325 if ((flags & DMU_DIRECTIO) && zfs_dio_page_aligned((void *)buf) &&
1326 zfs_dio_aligned(offset, size, dn->dn_datablksz)) {
1327 abd_t *data = abd_get_from_buf((void *)buf, size);
1328 error = dmu_write_abd(dn, offset, size, data, flags, tx);
1329 abd_free(data);
1330 return (error);
1331 }
1332 flags &= ~DMU_DIRECTIO;
1333
1334 VERIFY0(dmu_buf_hold_array_by_dnode(dn, offset, size,
1335 FALSE, FTAG, &numbufs, &dbp, flags));
1336 dmu_write_impl(dbp, numbufs, offset, size, buf, tx, flags);
1337 dmu_buf_rele_array(dbp, numbufs, FTAG);
1338 return (0);
1339 }
1340
1341 void
dmu_prealloc(objset_t * os,uint64_t object,uint64_t offset,uint64_t size,dmu_tx_t * tx)1342 dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
1343 dmu_tx_t *tx)
1344 {
1345 dmu_buf_t **dbp;
1346 int numbufs, i;
1347
1348 if (size == 0)
1349 return;
1350
1351 VERIFY0(dmu_buf_hold_array(os, object, offset, size,
1352 FALSE, FTAG, &numbufs, &dbp, DMU_READ_PREFETCH));
1353
1354 for (i = 0; i < numbufs; i++) {
1355 dmu_buf_t *db = dbp[i];
1356
1357 dmu_buf_will_not_fill(db, tx);
1358 }
1359 dmu_buf_rele_array(dbp, numbufs, FTAG);
1360 }
1361
1362 void
dmu_write_embedded(objset_t * os,uint64_t object,uint64_t offset,void * data,uint8_t etype,uint8_t comp,int uncompressed_size,int compressed_size,int byteorder,dmu_tx_t * tx)1363 dmu_write_embedded(objset_t *os, uint64_t object, uint64_t offset,
1364 void *data, uint8_t etype, uint8_t comp, int uncompressed_size,
1365 int compressed_size, int byteorder, dmu_tx_t *tx)
1366 {
1367 dmu_buf_t *db;
1368
1369 ASSERT3U(etype, <, NUM_BP_EMBEDDED_TYPES);
1370 ASSERT3U(comp, <, ZIO_COMPRESS_FUNCTIONS);
1371 VERIFY0(dmu_buf_hold_noread(os, object, offset,
1372 FTAG, &db));
1373
1374 dmu_buf_write_embedded(db,
1375 data, (bp_embedded_type_t)etype, (enum zio_compress)comp,
1376 uncompressed_size, compressed_size, byteorder, tx);
1377
1378 dmu_buf_rele(db, FTAG);
1379 }
1380
1381 void
dmu_redact(objset_t * os,uint64_t object,uint64_t offset,uint64_t size,dmu_tx_t * tx)1382 dmu_redact(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
1383 dmu_tx_t *tx)
1384 {
1385 int numbufs, i;
1386 dmu_buf_t **dbp;
1387
1388 VERIFY0(dmu_buf_hold_array(os, object, offset, size, FALSE, FTAG,
1389 &numbufs, &dbp, DMU_READ_PREFETCH));
1390 for (i = 0; i < numbufs; i++)
1391 dmu_buf_redact(dbp[i], tx);
1392 dmu_buf_rele_array(dbp, numbufs, FTAG);
1393 }
1394
1395 #ifdef _KERNEL
1396 int
dmu_read_uio_dnode(dnode_t * dn,zfs_uio_t * uio,uint64_t size,dmu_flags_t flags)1397 dmu_read_uio_dnode(dnode_t *dn, zfs_uio_t *uio, uint64_t size,
1398 dmu_flags_t flags)
1399 {
1400 dmu_buf_t **dbp;
1401 int numbufs, i, err;
1402
1403 if ((flags & DMU_DIRECTIO) && (uio->uio_extflg & UIO_DIRECT))
1404 return (dmu_read_uio_direct(dn, uio, size, flags));
1405 flags &= ~DMU_DIRECTIO;
1406
1407 /*
1408 * NB: we could do this block-at-a-time, but it's nice
1409 * to be reading in parallel.
1410 */
1411 err = dmu_buf_hold_array_by_dnode(dn, zfs_uio_offset(uio), size,
1412 TRUE, FTAG, &numbufs, &dbp, flags);
1413 if (err)
1414 return (err);
1415
1416 for (i = 0; i < numbufs; i++) {
1417 uint64_t tocpy;
1418 int64_t bufoff;
1419 dmu_buf_t *db = dbp[i];
1420
1421 ASSERT(size > 0);
1422
1423 bufoff = zfs_uio_offset(uio) - db->db_offset;
1424 tocpy = MIN(db->db_size - bufoff, size);
1425
1426 ASSERT(db->db_data != NULL);
1427 err = zfs_uio_fault_move((char *)db->db_data + bufoff, tocpy,
1428 UIO_READ, uio);
1429
1430 if (err)
1431 break;
1432
1433 size -= tocpy;
1434 }
1435 dmu_buf_rele_array(dbp, numbufs, FTAG);
1436
1437 return (err);
1438 }
1439
1440 /*
1441 * Read 'size' bytes into the uio buffer.
1442 * From object zdb->db_object.
1443 * Starting at zfs_uio_offset(uio).
1444 *
1445 * If the caller already has a dbuf in the target object
1446 * (e.g. its bonus buffer), this routine is faster than dmu_read_uio(),
1447 * because we don't have to find the dnode_t for the object.
1448 */
1449 int
dmu_read_uio_dbuf(dmu_buf_t * zdb,zfs_uio_t * uio,uint64_t size,dmu_flags_t flags)1450 dmu_read_uio_dbuf(dmu_buf_t *zdb, zfs_uio_t *uio, uint64_t size,
1451 dmu_flags_t flags)
1452 {
1453 dmu_buf_impl_t *db = (dmu_buf_impl_t *)zdb;
1454 int err;
1455
1456 if (size == 0)
1457 return (0);
1458
1459 DB_DNODE_ENTER(db);
1460 err = dmu_read_uio_dnode(DB_DNODE(db), uio, size, flags);
1461 DB_DNODE_EXIT(db);
1462
1463 return (err);
1464 }
1465
1466 /*
1467 * Read 'size' bytes into the uio buffer.
1468 * From the specified object
1469 * Starting at offset zfs_uio_offset(uio).
1470 */
1471 int
dmu_read_uio(objset_t * os,uint64_t object,zfs_uio_t * uio,uint64_t size,dmu_flags_t flags)1472 dmu_read_uio(objset_t *os, uint64_t object, zfs_uio_t *uio, uint64_t size,
1473 dmu_flags_t flags)
1474 {
1475 dnode_t *dn;
1476 int err;
1477
1478 if (size == 0)
1479 return (0);
1480
1481 err = dnode_hold(os, object, FTAG, &dn);
1482 if (err)
1483 return (err);
1484
1485 err = dmu_read_uio_dnode(dn, uio, size, flags);
1486
1487 dnode_rele(dn, FTAG);
1488
1489 return (err);
1490 }
1491
1492 int
dmu_write_uio_dnode(dnode_t * dn,zfs_uio_t * uio,uint64_t size,dmu_tx_t * tx,dmu_flags_t flags)1493 dmu_write_uio_dnode(dnode_t *dn, zfs_uio_t *uio, uint64_t size, dmu_tx_t *tx,
1494 dmu_flags_t flags)
1495 {
1496 dmu_buf_t **dbp;
1497 int numbufs;
1498 int err = 0;
1499 uint64_t write_size;
1500 dmu_flags_t oflags = flags;
1501
1502 top:
1503 write_size = size;
1504
1505 /*
1506 * We only allow Direct I/O writes to happen if we are block
1507 * sized aligned. Otherwise, we pass the write off to the ARC.
1508 */
1509 if ((flags & DMU_DIRECTIO) && (uio->uio_extflg & UIO_DIRECT) &&
1510 (write_size >= dn->dn_datablksz)) {
1511 if (zfs_dio_aligned(zfs_uio_offset(uio), write_size,
1512 dn->dn_datablksz)) {
1513 return (dmu_write_uio_direct(dn, uio, size, flags, tx));
1514 } else if (write_size > dn->dn_datablksz &&
1515 zfs_dio_offset_aligned(zfs_uio_offset(uio),
1516 dn->dn_datablksz)) {
1517 write_size =
1518 dn->dn_datablksz * (write_size / dn->dn_datablksz);
1519 err = dmu_write_uio_direct(dn, uio, write_size, flags,
1520 tx);
1521 if (err == 0) {
1522 size -= write_size;
1523 goto top;
1524 } else {
1525 return (err);
1526 }
1527 } else {
1528 write_size =
1529 P2PHASE(zfs_uio_offset(uio), dn->dn_datablksz);
1530 }
1531 }
1532 flags &= ~DMU_DIRECTIO;
1533
1534 err = dmu_buf_hold_array_by_dnode(dn, zfs_uio_offset(uio), write_size,
1535 FALSE, FTAG, &numbufs, &dbp, flags);
1536 if (err)
1537 return (err);
1538
1539 for (int i = 0; i < numbufs; i++) {
1540 uint64_t tocpy;
1541 int64_t bufoff;
1542 dmu_buf_t *db = dbp[i];
1543
1544 ASSERT(write_size > 0);
1545
1546 offset_t off = zfs_uio_offset(uio);
1547 bufoff = off - db->db_offset;
1548 tocpy = MIN(db->db_size - bufoff, write_size);
1549
1550 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
1551
1552 if (tocpy == db->db_size) {
1553 dmu_buf_will_fill_flags(db, tx, B_TRUE, flags);
1554 } else {
1555 if (i == numbufs - 1 && bufoff + tocpy < db->db_size) {
1556 if (bufoff == 0)
1557 flags |= DMU_PARTIAL_FIRST;
1558 else
1559 flags |= DMU_PARTIAL_MORE;
1560 }
1561 dmu_buf_will_dirty_flags(db, tx, flags);
1562 }
1563
1564 ASSERT(db->db_data != NULL);
1565 err = zfs_uio_fault_move((char *)db->db_data + bufoff,
1566 tocpy, UIO_WRITE, uio);
1567
1568 if (tocpy == db->db_size && dmu_buf_fill_done(db, tx, err)) {
1569 /* The fill was reverted. Undo any uio progress. */
1570 zfs_uio_advance(uio, off - zfs_uio_offset(uio));
1571 }
1572
1573 if (err)
1574 break;
1575
1576 write_size -= tocpy;
1577 size -= tocpy;
1578 }
1579
1580 IMPLY(err == 0, write_size == 0);
1581
1582 dmu_buf_rele_array(dbp, numbufs, FTAG);
1583
1584 if ((oflags & DMU_DIRECTIO) && (uio->uio_extflg & UIO_DIRECT) &&
1585 err == 0 && size > 0) {
1586 flags = oflags;
1587 goto top;
1588 }
1589 IMPLY(err == 0, size == 0);
1590
1591 return (err);
1592 }
1593
1594 /*
1595 * Write 'size' bytes from the uio buffer.
1596 * To object zdb->db_object.
1597 * Starting at offset zfs_uio_offset(uio).
1598 *
1599 * If the caller already has a dbuf in the target object
1600 * (e.g. its bonus buffer), this routine is faster than dmu_write_uio(),
1601 * because we don't have to find the dnode_t for the object.
1602 */
1603 int
dmu_write_uio_dbuf(dmu_buf_t * zdb,zfs_uio_t * uio,uint64_t size,dmu_tx_t * tx,dmu_flags_t flags)1604 dmu_write_uio_dbuf(dmu_buf_t *zdb, zfs_uio_t *uio, uint64_t size,
1605 dmu_tx_t *tx, dmu_flags_t flags)
1606 {
1607 dmu_buf_impl_t *db = (dmu_buf_impl_t *)zdb;
1608 int err;
1609
1610 if (size == 0)
1611 return (0);
1612
1613 DB_DNODE_ENTER(db);
1614 err = dmu_write_uio_dnode(DB_DNODE(db), uio, size, tx, flags);
1615 DB_DNODE_EXIT(db);
1616
1617 return (err);
1618 }
1619
1620 /*
1621 * Write 'size' bytes from the uio buffer.
1622 * To the specified object.
1623 * Starting at offset zfs_uio_offset(uio).
1624 */
1625 int
dmu_write_uio(objset_t * os,uint64_t object,zfs_uio_t * uio,uint64_t size,dmu_tx_t * tx,dmu_flags_t flags)1626 dmu_write_uio(objset_t *os, uint64_t object, zfs_uio_t *uio, uint64_t size,
1627 dmu_tx_t *tx, dmu_flags_t flags)
1628 {
1629 dnode_t *dn;
1630 int err;
1631
1632 if (size == 0)
1633 return (0);
1634
1635 err = dnode_hold(os, object, FTAG, &dn);
1636 if (err)
1637 return (err);
1638
1639 err = dmu_write_uio_dnode(dn, uio, size, tx, flags);
1640
1641 dnode_rele(dn, FTAG);
1642
1643 return (err);
1644 }
1645 #endif /* _KERNEL */
1646
1647 static void
dmu_cached_bps(spa_t * spa,blkptr_t * bps,uint_t nbps,uint64_t * l1sz,uint64_t * l2sz)1648 dmu_cached_bps(spa_t *spa, blkptr_t *bps, uint_t nbps,
1649 uint64_t *l1sz, uint64_t *l2sz)
1650 {
1651 int cached_flags;
1652
1653 if (bps == NULL)
1654 return;
1655
1656 for (size_t blk_off = 0; blk_off < nbps; blk_off++) {
1657 blkptr_t *bp = &bps[blk_off];
1658
1659 if (BP_IS_HOLE(bp))
1660 continue;
1661
1662 cached_flags = arc_cached(spa, bp);
1663 if (cached_flags == 0)
1664 continue;
1665
1666 if ((cached_flags & (ARC_CACHED_IN_L1 | ARC_CACHED_IN_L2)) ==
1667 ARC_CACHED_IN_L2)
1668 *l2sz += BP_GET_LSIZE(bp);
1669 else
1670 *l1sz += BP_GET_LSIZE(bp);
1671 }
1672 }
1673
1674 /*
1675 * Estimate DMU object cached size.
1676 */
1677 int
dmu_object_cached_size(objset_t * os,uint64_t object,uint64_t * l1sz,uint64_t * l2sz)1678 dmu_object_cached_size(objset_t *os, uint64_t object,
1679 uint64_t *l1sz, uint64_t *l2sz)
1680 {
1681 dnode_t *dn;
1682 dmu_object_info_t doi;
1683 int err = 0;
1684
1685 *l1sz = *l2sz = 0;
1686
1687 if (dnode_hold(os, object, FTAG, &dn) != 0)
1688 return (0);
1689
1690 if (dn->dn_nlevels < 2) {
1691 dnode_rele(dn, FTAG);
1692 return (0);
1693 }
1694
1695 dmu_object_info_from_dnode(dn, &doi);
1696
1697 for (uint64_t off = 0; off < doi.doi_max_offset &&
1698 dmu_prefetch_max > 0; off += dmu_prefetch_max) {
1699 /* dbuf_read doesn't prefetch L1 blocks. */
1700 dmu_prefetch_by_dnode(dn, 1, off,
1701 dmu_prefetch_max, ZIO_PRIORITY_SYNC_READ);
1702 }
1703
1704 /*
1705 * Hold all valid L1 blocks, asking ARC the status of each BP
1706 * contained in each such L1 block.
1707 */
1708 uint_t nbps = bp_span_in_blocks(dn->dn_indblkshift, 1);
1709 uint64_t l1blks = 1 + (dn->dn_maxblkid / nbps);
1710
1711 rw_enter(&dn->dn_struct_rwlock, RW_READER);
1712 for (uint64_t blk = 0; blk < l1blks; blk++) {
1713 dmu_buf_impl_t *db = NULL;
1714
1715 if (issig()) {
1716 /*
1717 * On interrupt, get out, and bubble up EINTR
1718 */
1719 err = EINTR;
1720 break;
1721 }
1722
1723 /*
1724 * If we get an i/o error here, the L1 can't be read,
1725 * and nothing under it could be cached, so we just
1726 * continue. Ignoring the error from dbuf_hold_impl
1727 * or from dbuf_read is then a reasonable choice.
1728 */
1729 err = dbuf_hold_impl(dn, 1, blk, B_TRUE, B_FALSE, FTAG, &db);
1730 if (err != 0) {
1731 /*
1732 * ignore error and continue
1733 */
1734 err = 0;
1735 continue;
1736 }
1737
1738 err = dbuf_read(db, NULL, DB_RF_CANFAIL);
1739 if (err == 0) {
1740 dmu_cached_bps(dmu_objset_spa(os), db->db.db_data,
1741 nbps, l1sz, l2sz);
1742 }
1743 /*
1744 * error may be ignored, and we continue
1745 */
1746 err = 0;
1747 dbuf_rele(db, FTAG);
1748 }
1749 rw_exit(&dn->dn_struct_rwlock);
1750
1751 dnode_rele(dn, FTAG);
1752 return (err);
1753 }
1754
1755 /*
1756 * Allocate a loaned anonymous arc buffer.
1757 */
1758 arc_buf_t *
dmu_request_arcbuf(dmu_buf_t * handle,int size)1759 dmu_request_arcbuf(dmu_buf_t *handle, int size)
1760 {
1761 dmu_buf_impl_t *db = (dmu_buf_impl_t *)handle;
1762
1763 return (arc_loan_buf(db->db_objset->os_spa, B_FALSE, size));
1764 }
1765
1766 /*
1767 * Free a loaned arc buffer.
1768 */
1769 void
dmu_return_arcbuf(arc_buf_t * buf)1770 dmu_return_arcbuf(arc_buf_t *buf)
1771 {
1772 arc_return_buf(buf, FTAG);
1773 arc_buf_destroy(buf, FTAG);
1774 }
1775
1776 /*
1777 * A "lightweight" write is faster than a regular write (e.g.
1778 * dmu_write_by_dnode() or dmu_assign_arcbuf_by_dnode()), because it avoids the
1779 * CPU cost of creating a dmu_buf_impl_t and arc_buf_[hdr_]_t. However, the
1780 * data can not be read or overwritten until the transaction's txg has been
1781 * synced. This makes it appropriate for workloads that are known to be
1782 * (temporarily) write-only, like "zfs receive".
1783 *
1784 * A single block is written, starting at the specified offset in bytes. If
1785 * the call is successful, it returns 0 and the provided abd has been
1786 * consumed (the caller should not free it).
1787 */
1788 int
dmu_lightweight_write_by_dnode(dnode_t * dn,uint64_t offset,abd_t * abd,const zio_prop_t * zp,zio_flag_t flags,dmu_tx_t * tx)1789 dmu_lightweight_write_by_dnode(dnode_t *dn, uint64_t offset, abd_t *abd,
1790 const zio_prop_t *zp, zio_flag_t flags, dmu_tx_t *tx)
1791 {
1792 dbuf_dirty_record_t *dr =
1793 dbuf_dirty_lightweight(dn, dbuf_whichblock(dn, 0, offset), tx);
1794 if (dr == NULL)
1795 return (SET_ERROR(EIO));
1796 dr->dt.dll.dr_abd = abd;
1797 dr->dt.dll.dr_props = *zp;
1798 dr->dt.dll.dr_flags = flags;
1799 return (0);
1800 }
1801
1802 /*
1803 * When possible directly assign passed loaned arc buffer to a dbuf.
1804 * If this is not possible copy the contents of passed arc buf via
1805 * dmu_write().
1806 */
1807 int
dmu_assign_arcbuf_by_dnode(dnode_t * dn,uint64_t offset,arc_buf_t * buf,dmu_tx_t * tx,dmu_flags_t flags)1808 dmu_assign_arcbuf_by_dnode(dnode_t *dn, uint64_t offset, arc_buf_t *buf,
1809 dmu_tx_t *tx, dmu_flags_t flags)
1810 {
1811 dmu_buf_impl_t *db;
1812 objset_t *os = dn->dn_objset;
1813 uint32_t blksz = (uint32_t)arc_buf_lsize(buf);
1814 uint64_t blkid;
1815
1816 rw_enter(&dn->dn_struct_rwlock, RW_READER);
1817 blkid = dbuf_whichblock(dn, 0, offset);
1818 db = dbuf_hold(dn, blkid, FTAG);
1819 rw_exit(&dn->dn_struct_rwlock);
1820 if (db == NULL)
1821 return (SET_ERROR(EIO));
1822
1823 /*
1824 * We can only assign if the offset is aligned and the arc buf is the
1825 * same size as the dbuf.
1826 */
1827 if (offset == db->db.db_offset && blksz == db->db.db_size) {
1828 zfs_racct_write(os->os_spa, blksz, 1, flags);
1829 dbuf_assign_arcbuf(db, buf, tx, flags);
1830 dbuf_rele(db, FTAG);
1831 } else {
1832 /* compressed bufs must always be assignable to their dbuf */
1833 ASSERT3U(arc_get_compression(buf), ==, ZIO_COMPRESS_OFF);
1834 ASSERT(!(buf->b_flags & ARC_BUF_FLAG_COMPRESSED));
1835
1836 dbuf_rele(db, FTAG);
1837 dmu_write_by_dnode(dn, offset, blksz, buf->b_data, tx, flags);
1838 dmu_return_arcbuf(buf);
1839 }
1840
1841 return (0);
1842 }
1843
1844 int
dmu_assign_arcbuf_by_dbuf(dmu_buf_t * handle,uint64_t offset,arc_buf_t * buf,dmu_tx_t * tx,dmu_flags_t flags)1845 dmu_assign_arcbuf_by_dbuf(dmu_buf_t *handle, uint64_t offset, arc_buf_t *buf,
1846 dmu_tx_t *tx, dmu_flags_t flags)
1847 {
1848 int err;
1849 dmu_buf_impl_t *db = (dmu_buf_impl_t *)handle;
1850
1851 DB_DNODE_ENTER(db);
1852 err = dmu_assign_arcbuf_by_dnode(DB_DNODE(db), offset, buf, tx, flags);
1853 DB_DNODE_EXIT(db);
1854
1855 return (err);
1856 }
1857
1858 void
dmu_sync_ready(zio_t * zio,arc_buf_t * buf,void * varg)1859 dmu_sync_ready(zio_t *zio, arc_buf_t *buf, void *varg)
1860 {
1861 (void) buf;
1862 dmu_sync_arg_t *dsa = varg;
1863
1864 if (zio->io_error == 0) {
1865 dbuf_dirty_record_t *dr = dsa->dsa_dr;
1866 blkptr_t *bp = zio->io_bp;
1867
1868 if (BP_IS_HOLE(bp)) {
1869 dmu_buf_t *db = NULL;
1870 if (dr)
1871 db = &(dr->dr_dbuf->db);
1872 else
1873 db = dsa->dsa_zgd->zgd_db;
1874 /*
1875 * A block of zeros may compress to a hole, but the
1876 * block size still needs to be known for replay.
1877 */
1878 BP_SET_LSIZE(bp, db->db_size);
1879 } else if (!BP_IS_EMBEDDED(bp)) {
1880 ASSERT0(BP_GET_LEVEL(bp));
1881 BP_SET_FILL(bp, 1);
1882 }
1883 }
1884 }
1885
1886 static void
dmu_sync_late_arrival_ready(zio_t * zio)1887 dmu_sync_late_arrival_ready(zio_t *zio)
1888 {
1889 dmu_sync_ready(zio, NULL, zio->io_private);
1890 }
1891
1892 void
dmu_sync_done(zio_t * zio,arc_buf_t * buf,void * varg)1893 dmu_sync_done(zio_t *zio, arc_buf_t *buf, void *varg)
1894 {
1895 (void) buf;
1896 dmu_sync_arg_t *dsa = varg;
1897 dbuf_dirty_record_t *dr = dsa->dsa_dr;
1898 dmu_buf_impl_t *db = dr->dr_dbuf;
1899 zgd_t *zgd = dsa->dsa_zgd;
1900
1901 /*
1902 * Record the vdev(s) backing this blkptr so they can be flushed after
1903 * the writes for the lwb have completed.
1904 */
1905 if (zgd && zio->io_error == 0) {
1906 zil_lwb_add_block(zgd->zgd_lwb, zgd->zgd_bp);
1907 }
1908
1909 mutex_enter(&db->db_mtx);
1910 ASSERT(dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC);
1911 if (zio->io_error == 0) {
1912 ASSERT0(dr->dt.dl.dr_has_raw_params);
1913 dr->dt.dl.dr_nopwrite = !!(zio->io_flags & ZIO_FLAG_NOPWRITE);
1914 if (dr->dt.dl.dr_nopwrite) {
1915 blkptr_t *bp = zio->io_bp;
1916 blkptr_t *bp_orig = &zio->io_bp_orig;
1917 uint8_t chksum = BP_GET_CHECKSUM(bp_orig);
1918
1919 ASSERT(BP_EQUAL(bp, bp_orig));
1920 VERIFY(BP_EQUAL(bp, db->db_blkptr));
1921 ASSERT(zio->io_prop.zp_compress != ZIO_COMPRESS_OFF);
1922 VERIFY(zio_checksum_table[chksum].ci_flags &
1923 ZCHECKSUM_FLAG_NOPWRITE);
1924 }
1925 dr->dt.dl.dr_overridden_by = *zio->io_bp;
1926 dr->dt.dl.dr_override_state = DR_OVERRIDDEN;
1927 dr->dt.dl.dr_copies = zio->io_prop.zp_copies;
1928 dr->dt.dl.dr_gang_copies = zio->io_prop.zp_gang_copies;
1929
1930 /*
1931 * Old style holes are filled with all zeros, whereas
1932 * new-style holes maintain their lsize, type, level,
1933 * and birth time (see zio_write_compress). While we
1934 * need to reset the BP_SET_LSIZE() call that happened
1935 * in dmu_sync_ready for old style holes, we do *not*
1936 * want to wipe out the information contained in new
1937 * style holes. Thus, only zero out the block pointer if
1938 * it's an old style hole.
1939 */
1940 if (BP_IS_HOLE(&dr->dt.dl.dr_overridden_by) &&
1941 BP_GET_LOGICAL_BIRTH(&dr->dt.dl.dr_overridden_by) == 0)
1942 BP_ZERO(&dr->dt.dl.dr_overridden_by);
1943 } else {
1944 dr->dt.dl.dr_override_state = DR_NOT_OVERRIDDEN;
1945 }
1946
1947 cv_broadcast(&db->db_changed);
1948 mutex_exit(&db->db_mtx);
1949
1950 if (dsa->dsa_done)
1951 dsa->dsa_done(dsa->dsa_zgd, zio->io_error);
1952
1953 kmem_free(dsa, sizeof (*dsa));
1954 }
1955
1956 static void
dmu_sync_late_arrival_done(zio_t * zio)1957 dmu_sync_late_arrival_done(zio_t *zio)
1958 {
1959 blkptr_t *bp = zio->io_bp;
1960 dmu_sync_arg_t *dsa = zio->io_private;
1961 zgd_t *zgd = dsa->dsa_zgd;
1962
1963 if (zio->io_error == 0) {
1964 /*
1965 * Record the vdev(s) backing this blkptr so they can be
1966 * flushed after the writes for the lwb have completed.
1967 */
1968 zil_lwb_add_block(zgd->zgd_lwb, zgd->zgd_bp);
1969
1970 if (!BP_IS_HOLE(bp)) {
1971 blkptr_t *bp_orig __maybe_unused = &zio->io_bp_orig;
1972 ASSERT(!(zio->io_flags & ZIO_FLAG_NOPWRITE));
1973 ASSERT(BP_IS_HOLE(bp_orig) || !BP_EQUAL(bp, bp_orig));
1974 ASSERT(BP_GET_BIRTH(zio->io_bp) == zio->io_txg);
1975 ASSERT(zio->io_txg > spa_syncing_txg(zio->io_spa));
1976 zio_free(zio->io_spa, zio->io_txg, zio->io_bp);
1977 }
1978 }
1979
1980 dmu_tx_commit(dsa->dsa_tx);
1981
1982 dsa->dsa_done(dsa->dsa_zgd, zio->io_error);
1983
1984 abd_free(zio->io_abd);
1985 kmem_free(dsa, sizeof (*dsa));
1986 }
1987
1988 static int
dmu_sync_late_arrival(zio_t * pio,objset_t * os,dmu_sync_cb_t * done,zgd_t * zgd,zio_prop_t * zp,zbookmark_phys_t * zb)1989 dmu_sync_late_arrival(zio_t *pio, objset_t *os, dmu_sync_cb_t *done, zgd_t *zgd,
1990 zio_prop_t *zp, zbookmark_phys_t *zb)
1991 {
1992 dmu_sync_arg_t *dsa;
1993 dmu_tx_t *tx;
1994 int error;
1995
1996 error = dbuf_read((dmu_buf_impl_t *)zgd->zgd_db, NULL,
1997 DB_RF_CANFAIL | DMU_READ_NO_PREFETCH | DMU_KEEP_CACHING);
1998 if (error != 0)
1999 return (error);
2000
2001 tx = dmu_tx_create(os);
2002 dmu_tx_hold_space(tx, zgd->zgd_db->db_size);
2003 /*
2004 * This transaction does not produce any dirty data or log blocks, so
2005 * it should not be throttled. All other cases wait for TXG sync, by
2006 * which time the log block we are writing will be obsolete, so we can
2007 * skip waiting and just return error here instead.
2008 */
2009 if (dmu_tx_assign(tx, DMU_TX_NOWAIT | DMU_TX_NOTHROTTLE) != 0) {
2010 dmu_tx_abort(tx);
2011 /* Make zl_get_data do txg_waited_synced() */
2012 return (SET_ERROR(EIO));
2013 }
2014
2015 /*
2016 * In order to prevent the zgd's lwb from being free'd prior to
2017 * dmu_sync_late_arrival_done() being called, we have to ensure
2018 * the lwb's "max txg" takes this tx's txg into account.
2019 */
2020 zil_lwb_add_txg(zgd->zgd_lwb, dmu_tx_get_txg(tx));
2021
2022 dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP);
2023 dsa->dsa_dr = NULL;
2024 dsa->dsa_done = done;
2025 dsa->dsa_zgd = zgd;
2026 dsa->dsa_tx = tx;
2027
2028 /*
2029 * Since we are currently syncing this txg, it's nontrivial to
2030 * determine what BP to nopwrite against, so we disable nopwrite.
2031 *
2032 * When syncing, the db_blkptr is initially the BP of the previous
2033 * txg. We can not nopwrite against it because it will be changed
2034 * (this is similar to the non-late-arrival case where the dbuf is
2035 * dirty in a future txg).
2036 *
2037 * Then dbuf_write_ready() sets bp_blkptr to the location we will write.
2038 * We can not nopwrite against it because although the BP will not
2039 * (typically) be changed, the data has not yet been persisted to this
2040 * location.
2041 *
2042 * Finally, when dbuf_write_done() is called, it is theoretically
2043 * possible to always nopwrite, because the data that was written in
2044 * this txg is the same data that we are trying to write. However we
2045 * would need to check that this dbuf is not dirty in any future
2046 * txg's (as we do in the normal dmu_sync() path). For simplicity, we
2047 * don't nopwrite in this case.
2048 */
2049 zp->zp_nopwrite = B_FALSE;
2050
2051 zio_nowait(zio_write(pio, os->os_spa, dmu_tx_get_txg(tx), zgd->zgd_bp,
2052 abd_get_from_buf(zgd->zgd_db->db_data, zgd->zgd_db->db_size),
2053 zgd->zgd_db->db_size, zgd->zgd_db->db_size, zp,
2054 dmu_sync_late_arrival_ready, NULL, dmu_sync_late_arrival_done,
2055 dsa, ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL, zb));
2056
2057 return (0);
2058 }
2059
2060 /*
2061 * Intent log support: sync the block associated with db to disk.
2062 * N.B. and XXX: the caller is responsible for making sure that the
2063 * data isn't changing while dmu_sync() is writing it.
2064 *
2065 * Return values:
2066 *
2067 * EEXIST: this txg has already been synced, so there's nothing to do.
2068 * The caller should not log the write.
2069 *
2070 * ENOENT: the block was dbuf_free_range()'d, so there's nothing to do.
2071 * The caller should not log the write.
2072 *
2073 * EALREADY: this block is already in the process of being synced.
2074 * The caller should track its progress (somehow).
2075 *
2076 * EIO: could not do the I/O.
2077 * The caller should do a txg_wait_synced().
2078 *
2079 * 0: the I/O has been initiated.
2080 * The caller should log this blkptr in the done callback.
2081 * It is possible that the I/O will fail, in which case
2082 * the error will be reported to the done callback and
2083 * propagated to pio from zio_done().
2084 */
2085 int
dmu_sync(zio_t * pio,uint64_t txg,dmu_sync_cb_t * done,zgd_t * zgd)2086 dmu_sync(zio_t *pio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd)
2087 {
2088 dmu_buf_impl_t *db = (dmu_buf_impl_t *)zgd->zgd_db;
2089 objset_t *os = db->db_objset;
2090 dsl_dataset_t *ds = os->os_dsl_dataset;
2091 dbuf_dirty_record_t *dr, *dr_next;
2092 dmu_sync_arg_t *dsa;
2093 zbookmark_phys_t zb;
2094 zio_prop_t zp;
2095
2096 ASSERT(pio != NULL);
2097 ASSERT(txg != 0);
2098
2099 SET_BOOKMARK(&zb, ds->ds_object,
2100 db->db.db_object, db->db_level, db->db_blkid);
2101
2102 DB_DNODE_ENTER(db);
2103 dmu_write_policy(os, DB_DNODE(db), db->db_level, WP_DMU_SYNC, &zp);
2104 DB_DNODE_EXIT(db);
2105
2106 /*
2107 * If we're frozen (running ziltest), we always need to generate a bp.
2108 */
2109 if (txg > spa_freeze_txg(os->os_spa))
2110 return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb));
2111
2112 /*
2113 * Grabbing db_mtx now provides a barrier between dbuf_sync_leaf()
2114 * and us. If we determine that this txg is not yet syncing,
2115 * but it begins to sync a moment later, that's OK because the
2116 * sync thread will block in dbuf_sync_leaf() until we drop db_mtx.
2117 */
2118 mutex_enter(&db->db_mtx);
2119
2120 if (txg <= spa_last_synced_txg(os->os_spa)) {
2121 /*
2122 * This txg has already synced. There's nothing to do.
2123 */
2124 mutex_exit(&db->db_mtx);
2125 return (SET_ERROR(EEXIST));
2126 }
2127
2128 if (txg <= spa_syncing_txg(os->os_spa)) {
2129 /*
2130 * This txg is currently syncing, so we can't mess with
2131 * the dirty record anymore; just write a new log block.
2132 */
2133 mutex_exit(&db->db_mtx);
2134 return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb));
2135 }
2136
2137 dr = dbuf_find_dirty_eq(db, txg);
2138
2139 if (dr == NULL) {
2140 /*
2141 * There's no dr for this dbuf, so it must have been freed.
2142 * There's no need to log writes to freed blocks, so we're done.
2143 */
2144 mutex_exit(&db->db_mtx);
2145 return (SET_ERROR(ENOENT));
2146 }
2147
2148 dr_next = list_next(&db->db_dirty_records, dr);
2149 ASSERT(dr_next == NULL || dr_next->dr_txg < txg);
2150
2151 if (db->db_blkptr != NULL) {
2152 /*
2153 * We need to fill in zgd_bp with the current blkptr so that
2154 * the nopwrite code can check if we're writing the same
2155 * data that's already on disk. We can only nopwrite if we
2156 * are sure that after making the copy, db_blkptr will not
2157 * change until our i/o completes. We ensure this by
2158 * holding the db_mtx, and only allowing nopwrite if the
2159 * block is not already dirty (see below). This is verified
2160 * by dmu_sync_done(), which VERIFYs that the db_blkptr has
2161 * not changed.
2162 */
2163 *zgd->zgd_bp = *db->db_blkptr;
2164 }
2165
2166 /*
2167 * Assume the on-disk data is X, the current syncing data (in
2168 * txg - 1) is Y, and the current in-memory data is Z (currently
2169 * in dmu_sync).
2170 *
2171 * We usually want to perform a nopwrite if X and Z are the
2172 * same. However, if Y is different (i.e. the BP is going to
2173 * change before this write takes effect), then a nopwrite will
2174 * be incorrect - we would override with X, which could have
2175 * been freed when Y was written.
2176 *
2177 * (Note that this is not a concern when we are nop-writing from
2178 * syncing context, because X and Y must be identical, because
2179 * all previous txgs have been synced.)
2180 *
2181 * Therefore, we disable nopwrite if the current BP could change
2182 * before this TXG. There are two ways it could change: by
2183 * being dirty (dr_next is non-NULL), or by being freed
2184 * (dnode_block_freed()). This behavior is verified by
2185 * zio_done(), which VERIFYs that the override BP is identical
2186 * to the on-disk BP.
2187 */
2188 if (dr_next != NULL) {
2189 zp.zp_nopwrite = B_FALSE;
2190 } else {
2191 DB_DNODE_ENTER(db);
2192 if (dnode_block_freed(DB_DNODE(db), db->db_blkid))
2193 zp.zp_nopwrite = B_FALSE;
2194 DB_DNODE_EXIT(db);
2195 }
2196
2197 ASSERT(dr->dr_txg == txg);
2198 if (dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC ||
2199 dr->dt.dl.dr_override_state == DR_OVERRIDDEN) {
2200 /*
2201 * We have already issued a sync write for this buffer,
2202 * or this buffer has already been synced. It could not
2203 * have been dirtied since, or we would have cleared the state.
2204 */
2205 mutex_exit(&db->db_mtx);
2206 return (SET_ERROR(EALREADY));
2207 }
2208
2209 ASSERT0(dr->dt.dl.dr_has_raw_params);
2210 ASSERT(dr->dt.dl.dr_override_state == DR_NOT_OVERRIDDEN);
2211 dr->dt.dl.dr_override_state = DR_IN_DMU_SYNC;
2212 mutex_exit(&db->db_mtx);
2213
2214 dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP);
2215 dsa->dsa_dr = dr;
2216 dsa->dsa_done = done;
2217 dsa->dsa_zgd = zgd;
2218 dsa->dsa_tx = NULL;
2219
2220 zio_nowait(arc_write(pio, os->os_spa, txg, zgd->zgd_bp,
2221 dr->dt.dl.dr_data, !DBUF_IS_CACHEABLE(db),
2222 dbuf_is_l2cacheable(db, NULL), &zp, dmu_sync_ready, NULL,
2223 dmu_sync_done, dsa, ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL,
2224 &zb));
2225
2226 return (0);
2227 }
2228
2229 int
dmu_object_set_nlevels(objset_t * os,uint64_t object,int nlevels,dmu_tx_t * tx)2230 dmu_object_set_nlevels(objset_t *os, uint64_t object, int nlevels, dmu_tx_t *tx)
2231 {
2232 dnode_t *dn;
2233 int err;
2234
2235 err = dnode_hold(os, object, FTAG, &dn);
2236 if (err)
2237 return (err);
2238 err = dnode_set_nlevels(dn, nlevels, tx);
2239 dnode_rele(dn, FTAG);
2240 return (err);
2241 }
2242
2243 int
dmu_object_set_blocksize(objset_t * os,uint64_t object,uint64_t size,int ibs,dmu_tx_t * tx)2244 dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, int ibs,
2245 dmu_tx_t *tx)
2246 {
2247 dnode_t *dn;
2248 int err;
2249
2250 err = dnode_hold(os, object, FTAG, &dn);
2251 if (err)
2252 return (err);
2253 err = dnode_set_blksz(dn, size, ibs, tx);
2254 dnode_rele(dn, FTAG);
2255 return (err);
2256 }
2257
2258 int
dmu_object_set_maxblkid(objset_t * os,uint64_t object,uint64_t maxblkid,dmu_tx_t * tx)2259 dmu_object_set_maxblkid(objset_t *os, uint64_t object, uint64_t maxblkid,
2260 dmu_tx_t *tx)
2261 {
2262 dnode_t *dn;
2263 int err;
2264
2265 err = dnode_hold(os, object, FTAG, &dn);
2266 if (err)
2267 return (err);
2268 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
2269 dnode_new_blkid(dn, maxblkid, tx, B_FALSE, B_TRUE);
2270 rw_exit(&dn->dn_struct_rwlock);
2271 dnode_rele(dn, FTAG);
2272 return (0);
2273 }
2274
2275 void
dmu_object_set_checksum(objset_t * os,uint64_t object,uint8_t checksum,dmu_tx_t * tx)2276 dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum,
2277 dmu_tx_t *tx)
2278 {
2279 dnode_t *dn;
2280
2281 /*
2282 * Send streams include each object's checksum function. This
2283 * check ensures that the receiving system can understand the
2284 * checksum function transmitted.
2285 */
2286 ASSERT3U(checksum, <, ZIO_CHECKSUM_LEGACY_FUNCTIONS);
2287
2288 VERIFY0(dnode_hold(os, object, FTAG, &dn));
2289 ASSERT3U(checksum, <, ZIO_CHECKSUM_FUNCTIONS);
2290 dn->dn_checksum = checksum;
2291 dnode_setdirty(dn, tx);
2292 dnode_rele(dn, FTAG);
2293 }
2294
2295 void
dmu_object_set_compress(objset_t * os,uint64_t object,uint8_t compress,dmu_tx_t * tx)2296 dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress,
2297 dmu_tx_t *tx)
2298 {
2299 dnode_t *dn;
2300
2301 /*
2302 * Send streams include each object's compression function. This
2303 * check ensures that the receiving system can understand the
2304 * compression function transmitted.
2305 */
2306 ASSERT3U(compress, <, ZIO_COMPRESS_LEGACY_FUNCTIONS);
2307
2308 VERIFY0(dnode_hold(os, object, FTAG, &dn));
2309 dn->dn_compress = compress;
2310 dnode_setdirty(dn, tx);
2311 dnode_rele(dn, FTAG);
2312 }
2313
2314 /*
2315 * When the "redundant_metadata" property is set to "most", only indirect
2316 * blocks of this level and higher will have an additional ditto block.
2317 */
2318 static const int zfs_redundant_metadata_most_ditto_level = 2;
2319
2320 void
dmu_write_policy(objset_t * os,dnode_t * dn,int level,int wp,zio_prop_t * zp)2321 dmu_write_policy(objset_t *os, dnode_t *dn, int level, int wp, zio_prop_t *zp)
2322 {
2323 dmu_object_type_t type = dn ? dn->dn_type : DMU_OT_OBJSET;
2324 boolean_t ismd = (level > 0 || DMU_OT_IS_METADATA(type) ||
2325 (wp & WP_SPILL));
2326 enum zio_checksum checksum = os->os_checksum;
2327 enum zio_compress compress = os->os_compress;
2328 uint8_t complevel = os->os_complevel;
2329 enum zio_checksum dedup_checksum = os->os_dedup_checksum;
2330 boolean_t dedup = B_FALSE;
2331 boolean_t nopwrite = B_FALSE;
2332 boolean_t dedup_verify = os->os_dedup_verify;
2333 boolean_t encrypt = B_FALSE;
2334 int copies = os->os_copies;
2335 int gang_copies = os->os_copies;
2336
2337 /*
2338 * We maintain different write policies for each of the following
2339 * types of data:
2340 * 1. metadata
2341 * 2. preallocated blocks (i.e. level-0 blocks of a dump device)
2342 * 3. all other level 0 blocks
2343 */
2344 if (ismd) {
2345 /*
2346 * XXX -- we should design a compression algorithm
2347 * that specializes in arrays of bps.
2348 */
2349 compress = zio_compress_select(os->os_spa,
2350 ZIO_COMPRESS_ON, ZIO_COMPRESS_ON);
2351
2352 /*
2353 * Metadata always gets checksummed. If the data
2354 * checksum is multi-bit correctable, and it's not a
2355 * ZBT-style checksum, then it's suitable for metadata
2356 * as well. Otherwise, the metadata checksum defaults
2357 * to fletcher4.
2358 */
2359 if (!(zio_checksum_table[checksum].ci_flags &
2360 ZCHECKSUM_FLAG_METADATA) ||
2361 (zio_checksum_table[checksum].ci_flags &
2362 ZCHECKSUM_FLAG_EMBEDDED))
2363 checksum = ZIO_CHECKSUM_FLETCHER_4;
2364
2365 switch (os->os_redundant_metadata) {
2366 case ZFS_REDUNDANT_METADATA_ALL:
2367 copies++;
2368 gang_copies++;
2369 break;
2370 case ZFS_REDUNDANT_METADATA_MOST:
2371 if (level >= zfs_redundant_metadata_most_ditto_level ||
2372 DMU_OT_IS_METADATA(type) || (wp & WP_SPILL))
2373 copies++;
2374 if (level + 1 >=
2375 zfs_redundant_metadata_most_ditto_level ||
2376 DMU_OT_IS_METADATA(type) || (wp & WP_SPILL))
2377 gang_copies++;
2378 break;
2379 case ZFS_REDUNDANT_METADATA_SOME:
2380 if (DMU_OT_IS_CRITICAL(type, level)) {
2381 copies++;
2382 gang_copies++;
2383 } else if (DMU_OT_IS_METADATA(type)) {
2384 gang_copies++;
2385 }
2386 break;
2387 case ZFS_REDUNDANT_METADATA_NONE:
2388 break;
2389 }
2390
2391 if (dmu_ddt_copies > 0) {
2392 /*
2393 * If this tunable is set, and this is a write for a
2394 * dedup entry store (zap or log), then we treat it
2395 * something like ZFS_REDUNDANT_METADATA_MOST on a
2396 * regular dataset: this many copies, and one more for
2397 * "higher" indirect blocks. This specific exception is
2398 * necessary because dedup objects are stored in the
2399 * MOS, which always has the highest possible copies.
2400 */
2401 dmu_object_type_t stype =
2402 dn ? dn->dn_storage_type : DMU_OT_NONE;
2403 if (stype == DMU_OT_NONE)
2404 stype = type;
2405 if (stype == DMU_OT_DDT_ZAP) {
2406 copies = dmu_ddt_copies;
2407 if (level >=
2408 zfs_redundant_metadata_most_ditto_level)
2409 copies++;
2410 }
2411 }
2412 } else if (wp & WP_NOFILL) {
2413 ASSERT0(level);
2414
2415 /*
2416 * If we're writing preallocated blocks, we aren't actually
2417 * writing them so don't set any policy properties. These
2418 * blocks are currently only used by an external subsystem
2419 * outside of zfs (i.e. dump) and not written by the zio
2420 * pipeline.
2421 */
2422 compress = ZIO_COMPRESS_OFF;
2423 checksum = ZIO_CHECKSUM_OFF;
2424 } else {
2425 compress = zio_compress_select(os->os_spa, dn->dn_compress,
2426 compress);
2427 complevel = zio_complevel_select(os->os_spa, compress,
2428 complevel, complevel);
2429
2430 /*
2431 * Storing many references to an all zeros block in the dedup
2432 * table would be expensive. Instead, if dedup is enabled,
2433 * store them as holes even if compression is not enabled.
2434 */
2435 if (compress == ZIO_COMPRESS_OFF &&
2436 dedup_checksum != ZIO_CHECKSUM_OFF)
2437 compress = ZIO_COMPRESS_EMPTY;
2438
2439 checksum = (dedup_checksum == ZIO_CHECKSUM_OFF) ?
2440 zio_checksum_select(dn->dn_checksum, checksum) :
2441 dedup_checksum;
2442
2443 /*
2444 * Determine dedup setting. If we are in dmu_sync(),
2445 * we won't actually dedup now because that's all
2446 * done in syncing context; but we do want to use the
2447 * dedup checksum. If the checksum is not strong
2448 * enough to ensure unique signatures, force
2449 * dedup_verify.
2450 */
2451 if (dedup_checksum != ZIO_CHECKSUM_OFF) {
2452 dedup = (wp & WP_DMU_SYNC) ? B_FALSE : B_TRUE;
2453 if (!(zio_checksum_table[checksum].ci_flags &
2454 ZCHECKSUM_FLAG_DEDUP))
2455 dedup_verify = B_TRUE;
2456 }
2457
2458 /*
2459 * Enable nopwrite if we have secure enough checksum
2460 * algorithm (see comment in zio_nop_write) and
2461 * compression is enabled. We don't enable nopwrite if
2462 * dedup is enabled as the two features are mutually
2463 * exclusive.
2464 */
2465 nopwrite = (!dedup && (zio_checksum_table[checksum].ci_flags &
2466 ZCHECKSUM_FLAG_NOPWRITE) &&
2467 compress != ZIO_COMPRESS_OFF && zfs_nopwrite_enabled);
2468
2469 if (os->os_redundant_metadata == ZFS_REDUNDANT_METADATA_ALL ||
2470 (os->os_redundant_metadata ==
2471 ZFS_REDUNDANT_METADATA_MOST &&
2472 zfs_redundant_metadata_most_ditto_level <= 1))
2473 gang_copies++;
2474 }
2475
2476 /*
2477 * All objects in an encrypted objset are protected from modification
2478 * via a MAC. Encrypted objects store their IV and salt in the last DVA
2479 * in the bp, so we cannot use all copies. Encrypted objects are also
2480 * not subject to nopwrite since writing the same data will still
2481 * result in a new ciphertext. Only encrypted blocks can be dedup'd
2482 * to avoid ambiguity in the dedup code since the DDT does not store
2483 * object types.
2484 */
2485 if (os->os_encrypted && (wp & WP_NOFILL) == 0) {
2486 encrypt = B_TRUE;
2487
2488 if (DMU_OT_IS_ENCRYPTED(type)) {
2489 copies = MIN(copies, SPA_DVAS_PER_BP - 1);
2490 gang_copies = MIN(gang_copies, SPA_DVAS_PER_BP - 1);
2491 nopwrite = B_FALSE;
2492 } else {
2493 dedup = B_FALSE;
2494 }
2495
2496 if (level <= 0 &&
2497 (type == DMU_OT_DNODE || type == DMU_OT_OBJSET)) {
2498 compress = ZIO_COMPRESS_EMPTY;
2499 }
2500 }
2501
2502 zp->zp_compress = compress;
2503 zp->zp_complevel = complevel;
2504 zp->zp_checksum = checksum;
2505 zp->zp_type = (wp & WP_SPILL) ? dn->dn_bonustype : type;
2506 zp->zp_level = level;
2507 zp->zp_copies = MIN(copies, spa_max_replication(os->os_spa));
2508 zp->zp_gang_copies = MIN(MAX(gang_copies, copies),
2509 spa_max_replication(os->os_spa));
2510 zp->zp_dedup = dedup;
2511 zp->zp_dedup_verify = dedup && dedup_verify;
2512 zp->zp_nopwrite = nopwrite;
2513 zp->zp_encrypt = encrypt;
2514 zp->zp_byteorder = ZFS_HOST_BYTEORDER;
2515 zp->zp_direct_write = (wp & WP_DIRECT_WR) ? B_TRUE : B_FALSE;
2516 zp->zp_rewrite = B_FALSE;
2517 memset(zp->zp_salt, 0, ZIO_DATA_SALT_LEN);
2518 memset(zp->zp_iv, 0, ZIO_DATA_IV_LEN);
2519 memset(zp->zp_mac, 0, ZIO_DATA_MAC_LEN);
2520 zp->zp_zpl_smallblk = (DMU_OT_IS_FILE(zp->zp_type) ||
2521 zp->zp_type == DMU_OT_ZVOL) ?
2522 os->os_zpl_special_smallblock : 0;
2523 zp->zp_storage_type = dn ? dn->dn_storage_type : DMU_OT_NONE;
2524
2525 ASSERT3U(zp->zp_compress, !=, ZIO_COMPRESS_INHERIT);
2526 }
2527
2528 /*
2529 * Reports the location of data and holes in an object. In order to
2530 * accurately report holes all dirty data must be synced to disk. This
2531 * causes extremely poor performance when seeking for holes in a dirty file.
2532 * As a compromise, only provide hole data when the dnode is clean. When
2533 * a dnode is dirty report the dnode as having no holes by returning EBUSY
2534 * which is always safe to do.
2535 */
2536 int
dmu_offset_next(objset_t * os,uint64_t object,boolean_t hole,uint64_t * off)2537 dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, uint64_t *off)
2538 {
2539 dnode_t *dn;
2540 uint64_t txg, maxtxg = 0;
2541 int err;
2542
2543 restart:
2544 err = dnode_hold(os, object, FTAG, &dn);
2545 if (err)
2546 return (err);
2547
2548 rw_enter(&dn->dn_struct_rwlock, RW_READER);
2549
2550 if (dnode_is_dirty(dn)) {
2551 /*
2552 * If the zfs_dmu_offset_next_sync module option is enabled
2553 * then hole reporting has been requested. Dirty dnodes
2554 * must be synced to disk to accurately report holes.
2555 *
2556 * Provided a RL_READER rangelock spanning 0-UINT64_MAX is
2557 * held by the caller only limited restarts will be required.
2558 * We tolerate callers which do not hold the rangelock by
2559 * returning EBUSY and not reporting holes after at most
2560 * TXG_CONCURRENT_STATES (3) restarts.
2561 */
2562 if (zfs_dmu_offset_next_sync) {
2563 rw_exit(&dn->dn_struct_rwlock);
2564 dnode_rele(dn, FTAG);
2565
2566 if (maxtxg == 0) {
2567 txg = spa_last_synced_txg(dmu_objset_spa(os));
2568 maxtxg = txg + TXG_CONCURRENT_STATES;
2569 } else if (txg >= maxtxg)
2570 return (SET_ERROR(EBUSY));
2571
2572 txg_wait_synced(dmu_objset_pool(os), ++txg);
2573 goto restart;
2574 }
2575
2576 err = SET_ERROR(EBUSY);
2577 } else {
2578 err = dnode_next_offset(dn, DNODE_FIND_HAVELOCK |
2579 (hole ? DNODE_FIND_HOLE : 0), off, 1, 1, 0);
2580 }
2581
2582 rw_exit(&dn->dn_struct_rwlock);
2583 dnode_rele(dn, FTAG);
2584
2585 return (err);
2586 }
2587
2588 int
dmu_read_l0_bps(objset_t * os,uint64_t object,uint64_t offset,uint64_t length,blkptr_t * bps,size_t * nbpsp)2589 dmu_read_l0_bps(objset_t *os, uint64_t object, uint64_t offset, uint64_t length,
2590 blkptr_t *bps, size_t *nbpsp)
2591 {
2592 dmu_buf_t **dbp, *dbuf;
2593 dmu_buf_impl_t *db;
2594 blkptr_t *bp;
2595 int error, numbufs;
2596
2597 error = dmu_buf_hold_array(os, object, offset, length, FALSE, FTAG,
2598 &numbufs, &dbp, DMU_READ_PREFETCH);
2599 if (error != 0) {
2600 if (error == ESRCH) {
2601 error = SET_ERROR(ENXIO);
2602 }
2603 return (error);
2604 }
2605
2606 ASSERT3U(numbufs, <=, *nbpsp);
2607
2608 for (int i = 0; i < numbufs; i++) {
2609 dbuf = dbp[i];
2610 db = (dmu_buf_impl_t *)dbuf;
2611
2612 mutex_enter(&db->db_mtx);
2613
2614 if (!list_is_empty(&db->db_dirty_records)) {
2615 dbuf_dirty_record_t *dr;
2616
2617 dr = list_head(&db->db_dirty_records);
2618 if (dr->dt.dl.dr_brtwrite) {
2619 /*
2620 * This is very special case where we clone a
2621 * block and in the same transaction group we
2622 * read its BP (most likely to clone the clone).
2623 */
2624 bp = &dr->dt.dl.dr_overridden_by;
2625 } else {
2626 /*
2627 * The block was modified in the same
2628 * transaction group.
2629 */
2630 mutex_exit(&db->db_mtx);
2631 error = SET_ERROR(EAGAIN);
2632 goto out;
2633 }
2634 } else {
2635 bp = db->db_blkptr;
2636 }
2637
2638 mutex_exit(&db->db_mtx);
2639
2640 if (bp == NULL) {
2641 /*
2642 * The file size was increased, but the block was never
2643 * written, otherwise we would either have the block
2644 * pointer or the dirty record and would not get here.
2645 * It is effectively a hole, so report it as such.
2646 */
2647 BP_ZERO(&bps[i]);
2648 continue;
2649 }
2650 /*
2651 * Make sure we clone only data blocks.
2652 */
2653 if (BP_IS_METADATA(bp) && !BP_IS_HOLE(bp)) {
2654 error = SET_ERROR(EINVAL);
2655 goto out;
2656 }
2657
2658 /*
2659 * If the block was allocated in transaction group that is not
2660 * yet synced, we could clone it, but we couldn't write this
2661 * operation into ZIL, or it may be impossible to replay, since
2662 * the block may appear not yet allocated at that point.
2663 */
2664 if (BP_GET_PHYSICAL_BIRTH(bp) > spa_freeze_txg(os->os_spa)) {
2665 error = SET_ERROR(EINVAL);
2666 goto out;
2667 }
2668 if (BP_GET_PHYSICAL_BIRTH(bp) >
2669 spa_last_synced_txg(os->os_spa)) {
2670 error = SET_ERROR(EAGAIN);
2671 goto out;
2672 }
2673
2674 bps[i] = *bp;
2675 }
2676
2677 *nbpsp = numbufs;
2678 out:
2679 dmu_buf_rele_array(dbp, numbufs, FTAG);
2680
2681 return (error);
2682 }
2683
2684 int
dmu_brt_clone(objset_t * os,uint64_t object,uint64_t offset,uint64_t length,dmu_tx_t * tx,const blkptr_t * bps,size_t nbps)2685 dmu_brt_clone(objset_t *os, uint64_t object, uint64_t offset, uint64_t length,
2686 dmu_tx_t *tx, const blkptr_t *bps, size_t nbps)
2687 {
2688 spa_t *spa;
2689 dmu_buf_t **dbp, *dbuf;
2690 dmu_buf_impl_t *db;
2691 struct dirty_leaf *dl;
2692 dbuf_dirty_record_t *dr;
2693 const blkptr_t *bp;
2694 int error = 0, i, numbufs;
2695
2696 spa = os->os_spa;
2697
2698 VERIFY0(dmu_buf_hold_array(os, object, offset, length, FALSE, FTAG,
2699 &numbufs, &dbp, DMU_READ_PREFETCH));
2700 ASSERT3U(nbps, ==, numbufs);
2701
2702 /*
2703 * Before we start cloning make sure that the dbufs sizes match new BPs
2704 * sizes. If they don't, that's a no-go, as we are not able to shrink
2705 * dbufs.
2706 */
2707 for (i = 0; i < numbufs; i++) {
2708 dbuf = dbp[i];
2709 db = (dmu_buf_impl_t *)dbuf;
2710 bp = &bps[i];
2711
2712 ASSERT3U(db->db.db_object, !=, DMU_META_DNODE_OBJECT);
2713 ASSERT0(db->db_level);
2714 ASSERT(db->db_blkid != DMU_BONUS_BLKID);
2715 ASSERT(db->db_blkid != DMU_SPILL_BLKID);
2716
2717 if (!BP_IS_HOLE(bp) && BP_GET_LSIZE(bp) != dbuf->db_size) {
2718 error = SET_ERROR(EXDEV);
2719 goto out;
2720 }
2721 }
2722
2723 for (i = 0; i < numbufs; i++) {
2724 dbuf = dbp[i];
2725 db = (dmu_buf_impl_t *)dbuf;
2726 bp = &bps[i];
2727
2728 dmu_buf_will_clone_or_dio(dbuf, tx);
2729
2730 mutex_enter(&db->db_mtx);
2731
2732 dr = list_head(&db->db_dirty_records);
2733 VERIFY(dr != NULL);
2734 ASSERT3U(dr->dr_txg, ==, tx->tx_txg);
2735 dl = &dr->dt.dl;
2736 ASSERT0(dl->dr_has_raw_params);
2737 dl->dr_overridden_by = *bp;
2738 if (!BP_IS_HOLE(bp) || BP_GET_LOGICAL_BIRTH(bp) != 0) {
2739 if (!BP_IS_EMBEDDED(bp)) {
2740 BP_SET_BIRTH(&dl->dr_overridden_by, dr->dr_txg,
2741 BP_GET_PHYSICAL_BIRTH(bp));
2742 BP_SET_REWRITE(&dl->dr_overridden_by, 0);
2743 } else {
2744 BP_SET_LOGICAL_BIRTH(&dl->dr_overridden_by,
2745 dr->dr_txg);
2746 }
2747 }
2748 dl->dr_brtwrite = B_TRUE;
2749 dl->dr_override_state = DR_OVERRIDDEN;
2750
2751 mutex_exit(&db->db_mtx);
2752
2753 /*
2754 * When data in embedded into BP there is no need to create
2755 * BRT entry as there is no data block. Just copy the BP as
2756 * it contains the data.
2757 */
2758 if (!BP_IS_HOLE(bp) && !BP_IS_EMBEDDED(bp)) {
2759 brt_pending_add(spa, bp, tx);
2760 }
2761 }
2762 out:
2763 dmu_buf_rele_array(dbp, numbufs, FTAG);
2764
2765 return (error);
2766 }
2767
2768 void
__dmu_object_info_from_dnode(dnode_t * dn,dmu_object_info_t * doi)2769 __dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi)
2770 {
2771 dnode_phys_t *dnp = dn->dn_phys;
2772
2773 doi->doi_data_block_size = dn->dn_datablksz;
2774 doi->doi_metadata_block_size = dn->dn_indblkshift ?
2775 1ULL << dn->dn_indblkshift : 0;
2776 doi->doi_type = dn->dn_type;
2777 doi->doi_bonus_type = dn->dn_bonustype;
2778 doi->doi_bonus_size = dn->dn_bonuslen;
2779 doi->doi_dnodesize = dn->dn_num_slots << DNODE_SHIFT;
2780 doi->doi_indirection = dn->dn_nlevels;
2781 doi->doi_checksum = dn->dn_checksum;
2782 doi->doi_compress = dn->dn_compress;
2783 doi->doi_nblkptr = dn->dn_nblkptr;
2784 doi->doi_physical_blocks_512 = (DN_USED_BYTES(dnp) + 256) >> 9;
2785 doi->doi_max_offset = (dn->dn_maxblkid + 1) * dn->dn_datablksz;
2786 doi->doi_fill_count = 0;
2787 for (int i = 0; i < dnp->dn_nblkptr; i++)
2788 doi->doi_fill_count += BP_GET_FILL(&dnp->dn_blkptr[i]);
2789 }
2790
2791 void
dmu_object_info_from_dnode(dnode_t * dn,dmu_object_info_t * doi)2792 dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi)
2793 {
2794 rw_enter(&dn->dn_struct_rwlock, RW_READER);
2795 mutex_enter(&dn->dn_mtx);
2796
2797 __dmu_object_info_from_dnode(dn, doi);
2798
2799 mutex_exit(&dn->dn_mtx);
2800 rw_exit(&dn->dn_struct_rwlock);
2801 }
2802
2803 /*
2804 * Get information on a DMU object.
2805 * If doi is NULL, just indicates whether the object exists.
2806 */
2807 int
dmu_object_info(objset_t * os,uint64_t object,dmu_object_info_t * doi)2808 dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi)
2809 {
2810 dnode_t *dn;
2811 int err = dnode_hold(os, object, FTAG, &dn);
2812
2813 if (err)
2814 return (err);
2815
2816 if (doi != NULL)
2817 dmu_object_info_from_dnode(dn, doi);
2818
2819 dnode_rele(dn, FTAG);
2820 return (0);
2821 }
2822
2823 /*
2824 * As above, but faster; can be used when you have a held dbuf in hand.
2825 */
2826 void
dmu_object_info_from_db(dmu_buf_t * db_fake,dmu_object_info_t * doi)2827 dmu_object_info_from_db(dmu_buf_t *db_fake, dmu_object_info_t *doi)
2828 {
2829 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
2830
2831 DB_DNODE_ENTER(db);
2832 dmu_object_info_from_dnode(DB_DNODE(db), doi);
2833 DB_DNODE_EXIT(db);
2834 }
2835
2836 /*
2837 * Faster still when you only care about the size.
2838 */
2839 void
dmu_object_size_from_db(dmu_buf_t * db_fake,uint32_t * blksize,u_longlong_t * nblk512)2840 dmu_object_size_from_db(dmu_buf_t *db_fake, uint32_t *blksize,
2841 u_longlong_t *nblk512)
2842 {
2843 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
2844 dnode_t *dn;
2845
2846 DB_DNODE_ENTER(db);
2847 dn = DB_DNODE(db);
2848
2849 *blksize = dn->dn_datablksz;
2850 /* add in number of slots used for the dnode itself */
2851 *nblk512 = ((DN_USED_BYTES(dn->dn_phys) + SPA_MINBLOCKSIZE/2) >>
2852 SPA_MINBLOCKSHIFT) + dn->dn_num_slots;
2853 DB_DNODE_EXIT(db);
2854 }
2855
2856 void
dmu_object_dnsize_from_db(dmu_buf_t * db_fake,int * dnsize)2857 dmu_object_dnsize_from_db(dmu_buf_t *db_fake, int *dnsize)
2858 {
2859 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
2860
2861 DB_DNODE_ENTER(db);
2862 *dnsize = DB_DNODE(db)->dn_num_slots << DNODE_SHIFT;
2863 DB_DNODE_EXIT(db);
2864 }
2865
2866 void
byteswap_uint64_array(void * vbuf,size_t size)2867 byteswap_uint64_array(void *vbuf, size_t size)
2868 {
2869 uint64_t *buf = vbuf;
2870 size_t count = size >> 3;
2871 int i;
2872
2873 ASSERT0((size & 7));
2874
2875 for (i = 0; i < count; i++)
2876 buf[i] = BSWAP_64(buf[i]);
2877 }
2878
2879 void
byteswap_uint32_array(void * vbuf,size_t size)2880 byteswap_uint32_array(void *vbuf, size_t size)
2881 {
2882 uint32_t *buf = vbuf;
2883 size_t count = size >> 2;
2884 int i;
2885
2886 ASSERT0((size & 3));
2887
2888 for (i = 0; i < count; i++)
2889 buf[i] = BSWAP_32(buf[i]);
2890 }
2891
2892 void
byteswap_uint16_array(void * vbuf,size_t size)2893 byteswap_uint16_array(void *vbuf, size_t size)
2894 {
2895 uint16_t *buf = vbuf;
2896 size_t count = size >> 1;
2897 int i;
2898
2899 ASSERT0((size & 1));
2900
2901 for (i = 0; i < count; i++)
2902 buf[i] = BSWAP_16(buf[i]);
2903 }
2904
2905 void
byteswap_uint8_array(void * vbuf,size_t size)2906 byteswap_uint8_array(void *vbuf, size_t size)
2907 {
2908 (void) vbuf, (void) size;
2909 }
2910
2911 void
dmu_init(void)2912 dmu_init(void)
2913 {
2914 abd_init();
2915 zfs_dbgmsg_init();
2916 sa_cache_init();
2917 dmu_objset_init();
2918 dnode_init();
2919 zfetch_init();
2920 dmu_tx_init();
2921 l2arc_init();
2922 arc_init();
2923 dbuf_init();
2924 }
2925
2926 void
dmu_fini(void)2927 dmu_fini(void)
2928 {
2929 arc_fini(); /* arc depends on l2arc, so arc must go first */
2930 l2arc_fini();
2931 dmu_tx_fini();
2932 zfetch_fini();
2933 dbuf_fini();
2934 dnode_fini();
2935 dmu_objset_fini();
2936 sa_cache_fini();
2937 zfs_dbgmsg_fini();
2938 abd_fini();
2939 }
2940
2941 EXPORT_SYMBOL(dmu_bonus_hold);
2942 EXPORT_SYMBOL(dmu_bonus_hold_by_dnode);
2943 EXPORT_SYMBOL(dmu_buf_hold_array_by_bonus);
2944 EXPORT_SYMBOL(dmu_buf_rele_array);
2945 EXPORT_SYMBOL(dmu_prefetch);
2946 EXPORT_SYMBOL(dmu_prefetch_by_dnode);
2947 EXPORT_SYMBOL(dmu_prefetch_dnode);
2948 EXPORT_SYMBOL(dmu_free_range);
2949 EXPORT_SYMBOL(dmu_free_long_range);
2950 EXPORT_SYMBOL(dmu_free_long_object);
2951 EXPORT_SYMBOL(dmu_read);
2952 EXPORT_SYMBOL(dmu_read_by_dnode);
2953 EXPORT_SYMBOL(dmu_read_uio);
2954 EXPORT_SYMBOL(dmu_read_uio_dbuf);
2955 EXPORT_SYMBOL(dmu_read_uio_dnode);
2956 EXPORT_SYMBOL(dmu_write);
2957 EXPORT_SYMBOL(dmu_write_by_dnode);
2958 EXPORT_SYMBOL(dmu_write_uio);
2959 EXPORT_SYMBOL(dmu_write_uio_dbuf);
2960 EXPORT_SYMBOL(dmu_write_uio_dnode);
2961 EXPORT_SYMBOL(dmu_prealloc);
2962 EXPORT_SYMBOL(dmu_object_info);
2963 EXPORT_SYMBOL(dmu_object_info_from_dnode);
2964 EXPORT_SYMBOL(dmu_object_info_from_db);
2965 EXPORT_SYMBOL(dmu_object_size_from_db);
2966 EXPORT_SYMBOL(dmu_object_dnsize_from_db);
2967 EXPORT_SYMBOL(dmu_object_set_nlevels);
2968 EXPORT_SYMBOL(dmu_object_set_blocksize);
2969 EXPORT_SYMBOL(dmu_object_set_maxblkid);
2970 EXPORT_SYMBOL(dmu_object_set_checksum);
2971 EXPORT_SYMBOL(dmu_object_set_compress);
2972 EXPORT_SYMBOL(dmu_offset_next);
2973 EXPORT_SYMBOL(dmu_write_policy);
2974 EXPORT_SYMBOL(dmu_sync);
2975 EXPORT_SYMBOL(dmu_request_arcbuf);
2976 EXPORT_SYMBOL(dmu_return_arcbuf);
2977 EXPORT_SYMBOL(dmu_assign_arcbuf_by_dnode);
2978 EXPORT_SYMBOL(dmu_assign_arcbuf_by_dbuf);
2979 EXPORT_SYMBOL(dmu_buf_hold);
2980 EXPORT_SYMBOL(dmu_ot);
2981
2982 ZFS_MODULE_PARAM(zfs, zfs_, nopwrite_enabled, INT, ZMOD_RW,
2983 "Enable NOP writes");
2984
2985 ZFS_MODULE_PARAM(zfs, zfs_, per_txg_dirty_frees_percent, UINT, ZMOD_RW,
2986 "Percentage of dirtied blocks from frees in one TXG");
2987
2988 ZFS_MODULE_PARAM(zfs, zfs_, dmu_offset_next_sync, INT, ZMOD_RW,
2989 "Enable forcing txg sync to find holes");
2990
2991 ZFS_MODULE_PARAM(zfs, , dmu_prefetch_max, UINT, ZMOD_RW,
2992 "Limit one prefetch call to this size");
2993
2994 ZFS_MODULE_PARAM(zfs, , dmu_ddt_copies, UINT, ZMOD_RW,
2995 "Override copies= for dedup objects");
2996