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Add linux kernel module support
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1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 */
24
25 #include <sys/dmu.h>
26 #include <sys/dmu_impl.h>
27 #include <sys/dmu_tx.h>
28 #include <sys/dbuf.h>
29 #include <sys/dnode.h>
30 #include <sys/zfs_context.h>
31 #include <sys/dmu_objset.h>
32 #include <sys/dmu_traverse.h>
33 #include <sys/dsl_dataset.h>
34 #include <sys/dsl_dir.h>
35 #include <sys/dsl_pool.h>
36 #include <sys/dsl_synctask.h>
37 #include <sys/dsl_prop.h>
38 #include <sys/dmu_zfetch.h>
39 #include <sys/zfs_ioctl.h>
40 #include <sys/zap.h>
41 #include <sys/zio_checksum.h>
42 #include <sys/sa.h>
43 #ifdef _KERNEL
44 #include <sys/vmsystm.h>
45 #include <sys/zfs_znode.h>
46 #endif
47
48 const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES] = {
49 { byteswap_uint8_array, TRUE, "unallocated" },
50 { zap_byteswap, TRUE, "object directory" },
51 { byteswap_uint64_array, TRUE, "object array" },
52 { byteswap_uint8_array, TRUE, "packed nvlist" },
53 { byteswap_uint64_array, TRUE, "packed nvlist size" },
54 { byteswap_uint64_array, TRUE, "bpobj" },
55 { byteswap_uint64_array, TRUE, "bpobj header" },
56 { byteswap_uint64_array, TRUE, "SPA space map header" },
57 { byteswap_uint64_array, TRUE, "SPA space map" },
58 { byteswap_uint64_array, TRUE, "ZIL intent log" },
59 { dnode_buf_byteswap, TRUE, "DMU dnode" },
60 { dmu_objset_byteswap, TRUE, "DMU objset" },
61 { byteswap_uint64_array, TRUE, "DSL directory" },
62 { zap_byteswap, TRUE, "DSL directory child map"},
63 { zap_byteswap, TRUE, "DSL dataset snap map" },
64 { zap_byteswap, TRUE, "DSL props" },
65 { byteswap_uint64_array, TRUE, "DSL dataset" },
66 { zfs_znode_byteswap, TRUE, "ZFS znode" },
67 { zfs_oldacl_byteswap, TRUE, "ZFS V0 ACL" },
68 { byteswap_uint8_array, FALSE, "ZFS plain file" },
69 { zap_byteswap, TRUE, "ZFS directory" },
70 { zap_byteswap, TRUE, "ZFS master node" },
71 { zap_byteswap, TRUE, "ZFS delete queue" },
72 { byteswap_uint8_array, FALSE, "zvol object" },
73 { zap_byteswap, TRUE, "zvol prop" },
74 { byteswap_uint8_array, FALSE, "other uint8[]" },
75 { byteswap_uint64_array, FALSE, "other uint64[]" },
76 { zap_byteswap, TRUE, "other ZAP" },
77 { zap_byteswap, TRUE, "persistent error log" },
78 { byteswap_uint8_array, TRUE, "SPA history" },
79 { byteswap_uint64_array, TRUE, "SPA history offsets" },
80 { zap_byteswap, TRUE, "Pool properties" },
81 { zap_byteswap, TRUE, "DSL permissions" },
82 { zfs_acl_byteswap, TRUE, "ZFS ACL" },
83 { byteswap_uint8_array, TRUE, "ZFS SYSACL" },
84 { byteswap_uint8_array, TRUE, "FUID table" },
85 { byteswap_uint64_array, TRUE, "FUID table size" },
86 { zap_byteswap, TRUE, "DSL dataset next clones"},
87 { zap_byteswap, TRUE, "scan work queue" },
88 { zap_byteswap, TRUE, "ZFS user/group used" },
89 { zap_byteswap, TRUE, "ZFS user/group quota" },
90 { zap_byteswap, TRUE, "snapshot refcount tags"},
91 { zap_byteswap, TRUE, "DDT ZAP algorithm" },
92 { zap_byteswap, TRUE, "DDT statistics" },
93 { byteswap_uint8_array, TRUE, "System attributes" },
94 { zap_byteswap, TRUE, "SA master node" },
95 { zap_byteswap, TRUE, "SA attr registration" },
96 { zap_byteswap, TRUE, "SA attr layouts" },
97 { zap_byteswap, TRUE, "scan translations" },
98 { byteswap_uint8_array, FALSE, "deduplicated block" },
99 { zap_byteswap, TRUE, "DSL deadlist map" },
100 { byteswap_uint64_array, TRUE, "DSL deadlist map hdr" },
101 { zap_byteswap, TRUE, "DSL dir clones" },
102 { byteswap_uint64_array, TRUE, "bpobj subobj" },
103 };
104
105 int
106 dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset,
107 void *tag, dmu_buf_t **dbp, int flags)
108 {
109 dnode_t *dn;
110 uint64_t blkid;
111 dmu_buf_impl_t *db;
112 int err;
113 int db_flags = DB_RF_CANFAIL;
114
115 if (flags & DMU_READ_NO_PREFETCH)
116 db_flags |= DB_RF_NOPREFETCH;
117
118 err = dnode_hold(os, object, FTAG, &dn);
119 if (err)
120 return (err);
121 blkid = dbuf_whichblock(dn, offset);
122 rw_enter(&dn->dn_struct_rwlock, RW_READER);
123 db = dbuf_hold(dn, blkid, tag);
124 rw_exit(&dn->dn_struct_rwlock);
125 if (db == NULL) {
126 err = EIO;
127 } else {
128 err = dbuf_read(db, NULL, db_flags);
129 if (err) {
130 dbuf_rele(db, tag);
131 db = NULL;
132 }
133 }
134
135 dnode_rele(dn, FTAG);
136 *dbp = &db->db; /* NULL db plus first field offset is NULL */
137 return (err);
138 }
139
140 int
141 dmu_bonus_max(void)
142 {
143 return (DN_MAX_BONUSLEN);
144 }
145
146 int
147 dmu_set_bonus(dmu_buf_t *db_fake, int newsize, dmu_tx_t *tx)
148 {
149 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
150 dnode_t *dn;
151 int error;
152
153 DB_DNODE_ENTER(db);
154 dn = DB_DNODE(db);
155
156 if (dn->dn_bonus != db) {
157 error = EINVAL;
158 } else if (newsize < 0 || newsize > db_fake->db_size) {
159 error = EINVAL;
160 } else {
161 dnode_setbonuslen(dn, newsize, tx);
162 error = 0;
163 }
164
165 DB_DNODE_EXIT(db);
166 return (error);
167 }
168
169 int
170 dmu_set_bonustype(dmu_buf_t *db_fake, dmu_object_type_t type, dmu_tx_t *tx)
171 {
172 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
173 dnode_t *dn;
174 int error;
175
176 DB_DNODE_ENTER(db);
177 dn = DB_DNODE(db);
178
179 if (type > DMU_OT_NUMTYPES) {
180 error = EINVAL;
181 } else if (dn->dn_bonus != db) {
182 error = EINVAL;
183 } else {
184 dnode_setbonus_type(dn, type, tx);
185 error = 0;
186 }
187
188 DB_DNODE_EXIT(db);
189 return (error);
190 }
191
192 dmu_object_type_t
193 dmu_get_bonustype(dmu_buf_t *db_fake)
194 {
195 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
196 dnode_t *dn;
197 dmu_object_type_t type;
198
199 DB_DNODE_ENTER(db);
200 dn = DB_DNODE(db);
201 type = dn->dn_bonustype;
202 DB_DNODE_EXIT(db);
203
204 return (type);
205 }
206
207 int
208 dmu_rm_spill(objset_t *os, uint64_t object, dmu_tx_t *tx)
209 {
210 dnode_t *dn;
211 int error;
212
213 error = dnode_hold(os, object, FTAG, &dn);
214 dbuf_rm_spill(dn, tx);
215 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
216 dnode_rm_spill(dn, tx);
217 rw_exit(&dn->dn_struct_rwlock);
218 dnode_rele(dn, FTAG);
219 return (error);
220 }
221
222 /*
223 * returns ENOENT, EIO, or 0.
224 */
225 int
226 dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **dbp)
227 {
228 dnode_t *dn;
229 dmu_buf_impl_t *db;
230 int error;
231
232 error = dnode_hold(os, object, FTAG, &dn);
233 if (error)
234 return (error);
235
236 rw_enter(&dn->dn_struct_rwlock, RW_READER);
237 if (dn->dn_bonus == NULL) {
238 rw_exit(&dn->dn_struct_rwlock);
239 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
240 if (dn->dn_bonus == NULL)
241 dbuf_create_bonus(dn);
242 }
243 db = dn->dn_bonus;
244
245 /* as long as the bonus buf is held, the dnode will be held */
246 if (refcount_add(&db->db_holds, tag) == 1) {
247 VERIFY(dnode_add_ref(dn, db));
248 (void) atomic_inc_32_nv(&dn->dn_dbufs_count);
249 }
250
251 /*
252 * Wait to drop dn_struct_rwlock until after adding the bonus dbuf's
253 * hold and incrementing the dbuf count to ensure that dnode_move() sees
254 * a dnode hold for every dbuf.
255 */
256 rw_exit(&dn->dn_struct_rwlock);
257
258 dnode_rele(dn, FTAG);
259
260 VERIFY(0 == dbuf_read(db, NULL, DB_RF_MUST_SUCCEED | DB_RF_NOPREFETCH));
261
262 *dbp = &db->db;
263 return (0);
264 }
265
266 /*
267 * returns ENOENT, EIO, or 0.
268 *
269 * This interface will allocate a blank spill dbuf when a spill blk
270 * doesn't already exist on the dnode.
271 *
272 * if you only want to find an already existing spill db, then
273 * dmu_spill_hold_existing() should be used.
274 */
275 int
276 dmu_spill_hold_by_dnode(dnode_t *dn, uint32_t flags, void *tag, dmu_buf_t **dbp)
277 {
278 dmu_buf_impl_t *db = NULL;
279 int err;
280
281 if ((flags & DB_RF_HAVESTRUCT) == 0)
282 rw_enter(&dn->dn_struct_rwlock, RW_READER);
283
284 db = dbuf_hold(dn, DMU_SPILL_BLKID, tag);
285
286 if ((flags & DB_RF_HAVESTRUCT) == 0)
287 rw_exit(&dn->dn_struct_rwlock);
288
289 ASSERT(db != NULL);
290 err = dbuf_read(db, NULL, flags);
291 if (err == 0)
292 *dbp = &db->db;
293 else
294 dbuf_rele(db, tag);
295 return (err);
296 }
297
298 int
299 dmu_spill_hold_existing(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp)
300 {
301 dmu_buf_impl_t *db = (dmu_buf_impl_t *)bonus;
302 dnode_t *dn;
303 int err;
304
305 DB_DNODE_ENTER(db);
306 dn = DB_DNODE(db);
307
308 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_SA) {
309 err = EINVAL;
310 } else {
311 rw_enter(&dn->dn_struct_rwlock, RW_READER);
312
313 if (!dn->dn_have_spill) {
314 err = ENOENT;
315 } else {
316 err = dmu_spill_hold_by_dnode(dn,
317 DB_RF_HAVESTRUCT | DB_RF_CANFAIL, tag, dbp);
318 }
319
320 rw_exit(&dn->dn_struct_rwlock);
321 }
322
323 DB_DNODE_EXIT(db);
324 return (err);
325 }
326
327 int
328 dmu_spill_hold_by_bonus(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp)
329 {
330 dmu_buf_impl_t *db = (dmu_buf_impl_t *)bonus;
331 dnode_t *dn;
332 int err;
333
334 DB_DNODE_ENTER(db);
335 dn = DB_DNODE(db);
336 err = dmu_spill_hold_by_dnode(dn, DB_RF_CANFAIL, tag, dbp);
337 DB_DNODE_EXIT(db);
338
339 return (err);
340 }
341
342 /*
343 * Note: longer-term, we should modify all of the dmu_buf_*() interfaces
344 * to take a held dnode rather than <os, object> -- the lookup is wasteful,
345 * and can induce severe lock contention when writing to several files
346 * whose dnodes are in the same block.
347 */
348 static int
349 dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset, uint64_t length,
350 int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp, uint32_t flags)
351 {
352 dsl_pool_t *dp = NULL;
353 dmu_buf_t **dbp;
354 uint64_t blkid, nblks, i;
355 uint32_t dbuf_flags;
356 int err;
357 zio_t *zio;
358 hrtime_t start = 0;
359
360 ASSERT(length <= DMU_MAX_ACCESS);
361
362 dbuf_flags = DB_RF_CANFAIL | DB_RF_NEVERWAIT | DB_RF_HAVESTRUCT;
363 if (flags & DMU_READ_NO_PREFETCH || length > zfetch_array_rd_sz)
364 dbuf_flags |= DB_RF_NOPREFETCH;
365
366 rw_enter(&dn->dn_struct_rwlock, RW_READER);
367 if (dn->dn_datablkshift) {
368 int blkshift = dn->dn_datablkshift;
369 nblks = (P2ROUNDUP(offset+length, 1ULL<<blkshift) -
370 P2ALIGN(offset, 1ULL<<blkshift)) >> blkshift;
371 } else {
372 if (offset + length > dn->dn_datablksz) {
373 zfs_panic_recover("zfs: accessing past end of object "
374 "%llx/%llx (size=%u access=%llu+%llu)",
375 (longlong_t)dn->dn_objset->
376 os_dsl_dataset->ds_object,
377 (longlong_t)dn->dn_object, dn->dn_datablksz,
378 (longlong_t)offset, (longlong_t)length);
379 rw_exit(&dn->dn_struct_rwlock);
380 return (EIO);
381 }
382 nblks = 1;
383 }
384 dbp = kmem_zalloc(sizeof (dmu_buf_t *) * nblks, KM_SLEEP);
385
386 if (dn->dn_objset->os_dsl_dataset)
387 dp = dn->dn_objset->os_dsl_dataset->ds_dir->dd_pool;
388 if (dp && dsl_pool_sync_context(dp))
389 start = gethrtime();
390 zio = zio_root(dn->dn_objset->os_spa, NULL, NULL, ZIO_FLAG_CANFAIL);
391 blkid = dbuf_whichblock(dn, offset);
392 for (i = 0; i < nblks; i++) {
393 dmu_buf_impl_t *db = dbuf_hold(dn, blkid+i, tag);
394 if (db == NULL) {
395 rw_exit(&dn->dn_struct_rwlock);
396 dmu_buf_rele_array(dbp, nblks, tag);
397 zio_nowait(zio);
398 return (EIO);
399 }
400 /* initiate async i/o */
401 if (read) {
402 (void) dbuf_read(db, zio, dbuf_flags);
403 }
404 dbp[i] = &db->db;
405 }
406 rw_exit(&dn->dn_struct_rwlock);
407
408 /* wait for async i/o */
409 err = zio_wait(zio);
410 /* track read overhead when we are in sync context */
411 if (dp && dsl_pool_sync_context(dp))
412 dp->dp_read_overhead += gethrtime() - start;
413 if (err) {
414 dmu_buf_rele_array(dbp, nblks, tag);
415 return (err);
416 }
417
418 /* wait for other io to complete */
419 if (read) {
420 for (i = 0; i < nblks; i++) {
421 dmu_buf_impl_t *db = (dmu_buf_impl_t *)dbp[i];
422 mutex_enter(&db->db_mtx);
423 while (db->db_state == DB_READ ||
424 db->db_state == DB_FILL)
425 cv_wait(&db->db_changed, &db->db_mtx);
426 if (db->db_state == DB_UNCACHED)
427 err = EIO;
428 mutex_exit(&db->db_mtx);
429 if (err) {
430 dmu_buf_rele_array(dbp, nblks, tag);
431 return (err);
432 }
433 }
434 }
435
436 *numbufsp = nblks;
437 *dbpp = dbp;
438 return (0);
439 }
440
441 static int
442 dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset,
443 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp)
444 {
445 dnode_t *dn;
446 int err;
447
448 err = dnode_hold(os, object, FTAG, &dn);
449 if (err)
450 return (err);
451
452 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag,
453 numbufsp, dbpp, DMU_READ_PREFETCH);
454
455 dnode_rele(dn, FTAG);
456
457 return (err);
458 }
459
460 int
461 dmu_buf_hold_array_by_bonus(dmu_buf_t *db_fake, uint64_t offset,
462 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp)
463 {
464 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
465 dnode_t *dn;
466 int err;
467
468 DB_DNODE_ENTER(db);
469 dn = DB_DNODE(db);
470 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag,
471 numbufsp, dbpp, DMU_READ_PREFETCH);
472 DB_DNODE_EXIT(db);
473
474 return (err);
475 }
476
477 void
478 dmu_buf_rele_array(dmu_buf_t **dbp_fake, int numbufs, void *tag)
479 {
480 int i;
481 dmu_buf_impl_t **dbp = (dmu_buf_impl_t **)dbp_fake;
482
483 if (numbufs == 0)
484 return;
485
486 for (i = 0; i < numbufs; i++) {
487 if (dbp[i])
488 dbuf_rele(dbp[i], tag);
489 }
490
491 kmem_free(dbp, sizeof (dmu_buf_t *) * numbufs);
492 }
493
494 void
495 dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, uint64_t len)
496 {
497 dnode_t *dn;
498 uint64_t blkid;
499 int nblks, i, err;
500
501 if (zfs_prefetch_disable)
502 return;
503
504 if (len == 0) { /* they're interested in the bonus buffer */
505 dn = DMU_META_DNODE(os);
506
507 if (object == 0 || object >= DN_MAX_OBJECT)
508 return;
509
510 rw_enter(&dn->dn_struct_rwlock, RW_READER);
511 blkid = dbuf_whichblock(dn, object * sizeof (dnode_phys_t));
512 dbuf_prefetch(dn, blkid);
513 rw_exit(&dn->dn_struct_rwlock);
514 return;
515 }
516
517 /*
518 * XXX - Note, if the dnode for the requested object is not
519 * already cached, we will do a *synchronous* read in the
520 * dnode_hold() call. The same is true for any indirects.
521 */
522 err = dnode_hold(os, object, FTAG, &dn);
523 if (err != 0)
524 return;
525
526 rw_enter(&dn->dn_struct_rwlock, RW_READER);
527 if (dn->dn_datablkshift) {
528 int blkshift = dn->dn_datablkshift;
529 nblks = (P2ROUNDUP(offset+len, 1<<blkshift) -
530 P2ALIGN(offset, 1<<blkshift)) >> blkshift;
531 } else {
532 nblks = (offset < dn->dn_datablksz);
533 }
534
535 if (nblks != 0) {
536 blkid = dbuf_whichblock(dn, offset);
537 for (i = 0; i < nblks; i++)
538 dbuf_prefetch(dn, blkid+i);
539 }
540
541 rw_exit(&dn->dn_struct_rwlock);
542
543 dnode_rele(dn, FTAG);
544 }
545
546 /*
547 * Get the next "chunk" of file data to free. We traverse the file from
548 * the end so that the file gets shorter over time (if we crashes in the
549 * middle, this will leave us in a better state). We find allocated file
550 * data by simply searching the allocated level 1 indirects.
551 */
552 static int
553 get_next_chunk(dnode_t *dn, uint64_t *start, uint64_t limit)
554 {
555 uint64_t len = *start - limit;
556 uint64_t blkcnt = 0;
557 uint64_t maxblks = DMU_MAX_ACCESS / (1ULL << (dn->dn_indblkshift + 1));
558 uint64_t iblkrange =
559 dn->dn_datablksz * EPB(dn->dn_indblkshift, SPA_BLKPTRSHIFT);
560
561 ASSERT(limit <= *start);
562
563 if (len <= iblkrange * maxblks) {
564 *start = limit;
565 return (0);
566 }
567 ASSERT(ISP2(iblkrange));
568
569 while (*start > limit && blkcnt < maxblks) {
570 int err;
571
572 /* find next allocated L1 indirect */
573 err = dnode_next_offset(dn,
574 DNODE_FIND_BACKWARDS, start, 2, 1, 0);
575
576 /* if there are no more, then we are done */
577 if (err == ESRCH) {
578 *start = limit;
579 return (0);
580 } else if (err) {
581 return (err);
582 }
583 blkcnt += 1;
584
585 /* reset offset to end of "next" block back */
586 *start = P2ALIGN(*start, iblkrange);
587 if (*start <= limit)
588 *start = limit;
589 else
590 *start -= 1;
591 }
592 return (0);
593 }
594
595 static int
596 dmu_free_long_range_impl(objset_t *os, dnode_t *dn, uint64_t offset,
597 uint64_t length, boolean_t free_dnode)
598 {
599 dmu_tx_t *tx;
600 uint64_t object_size, start, end, len;
601 boolean_t trunc = (length == DMU_OBJECT_END);
602 int align, err;
603
604 align = 1 << dn->dn_datablkshift;
605 ASSERT(align > 0);
606 object_size = align == 1 ? dn->dn_datablksz :
607 (dn->dn_maxblkid + 1) << dn->dn_datablkshift;
608
609 end = offset + length;
610 if (trunc || end > object_size)
611 end = object_size;
612 if (end <= offset)
613 return (0);
614 length = end - offset;
615
616 while (length) {
617 start = end;
618 /* assert(offset <= start) */
619 err = get_next_chunk(dn, &start, offset);
620 if (err)
621 return (err);
622 len = trunc ? DMU_OBJECT_END : end - start;
623
624 tx = dmu_tx_create(os);
625 dmu_tx_hold_free(tx, dn->dn_object, start, len);
626 err = dmu_tx_assign(tx, TXG_WAIT);
627 if (err) {
628 dmu_tx_abort(tx);
629 return (err);
630 }
631
632 dnode_free_range(dn, start, trunc ? -1 : len, tx);
633
634 if (start == 0 && free_dnode) {
635 ASSERT(trunc);
636 dnode_free(dn, tx);
637 }
638
639 length -= end - start;
640
641 dmu_tx_commit(tx);
642 end = start;
643 }
644 return (0);
645 }
646
647 int
648 dmu_free_long_range(objset_t *os, uint64_t object,
649 uint64_t offset, uint64_t length)
650 {
651 dnode_t *dn;
652 int err;
653
654 err = dnode_hold(os, object, FTAG, &dn);
655 if (err != 0)
656 return (err);
657 err = dmu_free_long_range_impl(os, dn, offset, length, FALSE);
658 dnode_rele(dn, FTAG);
659 return (err);
660 }
661
662 int
663 dmu_free_object(objset_t *os, uint64_t object)
664 {
665 dnode_t *dn;
666 dmu_tx_t *tx;
667 int err;
668
669 err = dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED,
670 FTAG, &dn);
671 if (err != 0)
672 return (err);
673 if (dn->dn_nlevels == 1) {
674 tx = dmu_tx_create(os);
675 dmu_tx_hold_bonus(tx, object);
676 dmu_tx_hold_free(tx, dn->dn_object, 0, DMU_OBJECT_END);
677 err = dmu_tx_assign(tx, TXG_WAIT);
678 if (err == 0) {
679 dnode_free_range(dn, 0, DMU_OBJECT_END, tx);
680 dnode_free(dn, tx);
681 dmu_tx_commit(tx);
682 } else {
683 dmu_tx_abort(tx);
684 }
685 } else {
686 err = dmu_free_long_range_impl(os, dn, 0, DMU_OBJECT_END, TRUE);
687 }
688 dnode_rele(dn, FTAG);
689 return (err);
690 }
691
692 int
693 dmu_free_range(objset_t *os, uint64_t object, uint64_t offset,
694 uint64_t size, dmu_tx_t *tx)
695 {
696 dnode_t *dn;
697 int err = dnode_hold(os, object, FTAG, &dn);
698 if (err)
699 return (err);
700 ASSERT(offset < UINT64_MAX);
701 ASSERT(size == -1ULL || size <= UINT64_MAX - offset);
702 dnode_free_range(dn, offset, size, tx);
703 dnode_rele(dn, FTAG);
704 return (0);
705 }
706
707 int
708 dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
709 void *buf, uint32_t flags)
710 {
711 dnode_t *dn;
712 dmu_buf_t **dbp;
713 int numbufs, err;
714
715 err = dnode_hold(os, object, FTAG, &dn);
716 if (err)
717 return (err);
718
719 /*
720 * Deal with odd block sizes, where there can't be data past the first
721 * block. If we ever do the tail block optimization, we will need to
722 * handle that here as well.
723 */
724 if (dn->dn_maxblkid == 0) {
725 int newsz = offset > dn->dn_datablksz ? 0 :
726 MIN(size, dn->dn_datablksz - offset);
727 bzero((char *)buf + newsz, size - newsz);
728 size = newsz;
729 }
730
731 while (size > 0) {
732 uint64_t mylen = MIN(size, DMU_MAX_ACCESS / 2);
733 int i;
734
735 /*
736 * NB: we could do this block-at-a-time, but it's nice
737 * to be reading in parallel.
738 */
739 err = dmu_buf_hold_array_by_dnode(dn, offset, mylen,
740 TRUE, FTAG, &numbufs, &dbp, flags);
741 if (err)
742 break;
743
744 for (i = 0; i < numbufs; i++) {
745 int tocpy;
746 int bufoff;
747 dmu_buf_t *db = dbp[i];
748
749 ASSERT(size > 0);
750
751 bufoff = offset - db->db_offset;
752 tocpy = (int)MIN(db->db_size - bufoff, size);
753
754 bcopy((char *)db->db_data + bufoff, buf, tocpy);
755
756 offset += tocpy;
757 size -= tocpy;
758 buf = (char *)buf + tocpy;
759 }
760 dmu_buf_rele_array(dbp, numbufs, FTAG);
761 }
762 dnode_rele(dn, FTAG);
763 return (err);
764 }
765
766 void
767 dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
768 const void *buf, dmu_tx_t *tx)
769 {
770 dmu_buf_t **dbp;
771 int numbufs, i;
772
773 if (size == 0)
774 return;
775
776 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size,
777 FALSE, FTAG, &numbufs, &dbp));
778
779 for (i = 0; i < numbufs; i++) {
780 int tocpy;
781 int bufoff;
782 dmu_buf_t *db = dbp[i];
783
784 ASSERT(size > 0);
785
786 bufoff = offset - db->db_offset;
787 tocpy = (int)MIN(db->db_size - bufoff, size);
788
789 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
790
791 if (tocpy == db->db_size)
792 dmu_buf_will_fill(db, tx);
793 else
794 dmu_buf_will_dirty(db, tx);
795
796 (void) memcpy((char *)db->db_data + bufoff, buf, tocpy);
797
798 if (tocpy == db->db_size)
799 dmu_buf_fill_done(db, tx);
800
801 offset += tocpy;
802 size -= tocpy;
803 buf = (char *)buf + tocpy;
804 }
805 dmu_buf_rele_array(dbp, numbufs, FTAG);
806 }
807
808 void
809 dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
810 dmu_tx_t *tx)
811 {
812 dmu_buf_t **dbp;
813 int numbufs, i;
814
815 if (size == 0)
816 return;
817
818 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size,
819 FALSE, FTAG, &numbufs, &dbp));
820
821 for (i = 0; i < numbufs; i++) {
822 dmu_buf_t *db = dbp[i];
823
824 dmu_buf_will_not_fill(db, tx);
825 }
826 dmu_buf_rele_array(dbp, numbufs, FTAG);
827 }
828
829 /*
830 * DMU support for xuio
831 */
832 kstat_t *xuio_ksp = NULL;
833
834 typedef struct xuio_stats {
835 /* loaned yet not returned arc_buf */
836 kstat_named_t xuiostat_onloan_rbuf;
837 kstat_named_t xuiostat_onloan_wbuf;
838 /* whether a copy is made when loaning out a read buffer */
839 kstat_named_t xuiostat_rbuf_copied;
840 kstat_named_t xuiostat_rbuf_nocopy;
841 /* whether a copy is made when assigning a write buffer */
842 kstat_named_t xuiostat_wbuf_copied;
843 kstat_named_t xuiostat_wbuf_nocopy;
844 } xuio_stats_t;
845
846 static xuio_stats_t xuio_stats = {
847 { "onloan_read_buf", KSTAT_DATA_UINT64 },
848 { "onloan_write_buf", KSTAT_DATA_UINT64 },
849 { "read_buf_copied", KSTAT_DATA_UINT64 },
850 { "read_buf_nocopy", KSTAT_DATA_UINT64 },
851 { "write_buf_copied", KSTAT_DATA_UINT64 },
852 { "write_buf_nocopy", KSTAT_DATA_UINT64 }
853 };
854
855 #define XUIOSTAT_INCR(stat, val) \
856 atomic_add_64(&xuio_stats.stat.value.ui64, (val))
857 #define XUIOSTAT_BUMP(stat) XUIOSTAT_INCR(stat, 1)
858
859 int
860 dmu_xuio_init(xuio_t *xuio, int nblk)
861 {
862 dmu_xuio_t *priv;
863 uio_t *uio = &xuio->xu_uio;
864
865 uio->uio_iovcnt = nblk;
866 uio->uio_iov = kmem_zalloc(nblk * sizeof (iovec_t), KM_SLEEP);
867
868 priv = kmem_zalloc(sizeof (dmu_xuio_t), KM_SLEEP);
869 priv->cnt = nblk;
870 priv->bufs = kmem_zalloc(nblk * sizeof (arc_buf_t *), KM_SLEEP);
871 priv->iovp = uio->uio_iov;
872 XUIO_XUZC_PRIV(xuio) = priv;
873
874 if (XUIO_XUZC_RW(xuio) == UIO_READ)
875 XUIOSTAT_INCR(xuiostat_onloan_rbuf, nblk);
876 else
877 XUIOSTAT_INCR(xuiostat_onloan_wbuf, nblk);
878
879 return (0);
880 }
881
882 void
883 dmu_xuio_fini(xuio_t *xuio)
884 {
885 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
886 int nblk = priv->cnt;
887
888 kmem_free(priv->iovp, nblk * sizeof (iovec_t));
889 kmem_free(priv->bufs, nblk * sizeof (arc_buf_t *));
890 kmem_free(priv, sizeof (dmu_xuio_t));
891
892 if (XUIO_XUZC_RW(xuio) == UIO_READ)
893 XUIOSTAT_INCR(xuiostat_onloan_rbuf, -nblk);
894 else
895 XUIOSTAT_INCR(xuiostat_onloan_wbuf, -nblk);
896 }
897
898 /*
899 * Initialize iov[priv->next] and priv->bufs[priv->next] with { off, n, abuf }
900 * and increase priv->next by 1.
901 */
902 int
903 dmu_xuio_add(xuio_t *xuio, arc_buf_t *abuf, offset_t off, size_t n)
904 {
905 struct iovec *iov;
906 uio_t *uio = &xuio->xu_uio;
907 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
908 int i = priv->next++;
909
910 ASSERT(i < priv->cnt);
911 ASSERT(off + n <= arc_buf_size(abuf));
912 iov = uio->uio_iov + i;
913 iov->iov_base = (char *)abuf->b_data + off;
914 iov->iov_len = n;
915 priv->bufs[i] = abuf;
916 return (0);
917 }
918
919 int
920 dmu_xuio_cnt(xuio_t *xuio)
921 {
922 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
923 return (priv->cnt);
924 }
925
926 arc_buf_t *
927 dmu_xuio_arcbuf(xuio_t *xuio, int i)
928 {
929 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
930
931 ASSERT(i < priv->cnt);
932 return (priv->bufs[i]);
933 }
934
935 void
936 dmu_xuio_clear(xuio_t *xuio, int i)
937 {
938 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
939
940 ASSERT(i < priv->cnt);
941 priv->bufs[i] = NULL;
942 }
943
944 static void
945 xuio_stat_init(void)
946 {
947 xuio_ksp = kstat_create("zfs", 0, "xuio_stats", "misc",
948 KSTAT_TYPE_NAMED, sizeof (xuio_stats) / sizeof (kstat_named_t),
949 KSTAT_FLAG_VIRTUAL);
950 if (xuio_ksp != NULL) {
951 xuio_ksp->ks_data = &xuio_stats;
952 kstat_install(xuio_ksp);
953 }
954 }
955
956 static void
957 xuio_stat_fini(void)
958 {
959 if (xuio_ksp != NULL) {
960 kstat_delete(xuio_ksp);
961 xuio_ksp = NULL;
962 }
963 }
964
965 void
966 xuio_stat_wbuf_copied()
967 {
968 XUIOSTAT_BUMP(xuiostat_wbuf_copied);
969 }
970
971 void
972 xuio_stat_wbuf_nocopy()
973 {
974 XUIOSTAT_BUMP(xuiostat_wbuf_nocopy);
975 }
976
977 #ifdef _KERNEL
978
979 /*
980 * Copy up to size bytes between arg_buf and req based on the data direction
981 * described by the req. If an entire req's data cannot be transfered the
982 * req's is updated such that it's current index and bv offsets correctly
983 * reference any residual data which could not be copied. The return value
984 * is the number of bytes successfully copied to arg_buf.
985 */
986 static int
987 dmu_req_copy(void *arg_buf, int size, int *offset, struct request *req)
988 {
989 struct bio_vec *bv;
990 struct req_iterator iter;
991 char *bv_buf;
992 int tocpy;
993
994 *offset = 0;
995 rq_for_each_segment(bv, req, iter) {
996
997 /* Fully consumed the passed arg_buf */
998 ASSERT3S(*offset, <=, size);
999 if (size == *offset)
1000 break;
1001
1002 /* Skip fully consumed bv's */
1003 if (bv->bv_len == 0)
1004 continue;
1005
1006 tocpy = MIN(bv->bv_len, size - *offset);
1007 ASSERT3S(tocpy, >=, 0);
1008
1009 bv_buf = page_address(bv->bv_page) + bv->bv_offset;
1010 ASSERT3P(bv_buf, !=, NULL);
1011
1012 if (rq_data_dir(req) == WRITE)
1013 memcpy(arg_buf + *offset, bv_buf, tocpy);
1014 else
1015 memcpy(bv_buf, arg_buf + *offset, tocpy);
1016
1017 *offset += tocpy;
1018 bv->bv_offset += tocpy;
1019 bv->bv_len -= tocpy;
1020 }
1021
1022 return 0;
1023 }
1024
1025 int
1026 dmu_read_req(objset_t *os, uint64_t object, struct request *req)
1027 {
1028 uint64_t size = blk_rq_bytes(req);
1029 uint64_t offset = blk_rq_pos(req) << 9;
1030 dmu_buf_t **dbp;
1031 int numbufs, i, err;
1032
1033 /*
1034 * NB: we could do this block-at-a-time, but it's nice
1035 * to be reading in parallel.
1036 */
1037 err = dmu_buf_hold_array(os, object, offset, size, TRUE, FTAG,
1038 &numbufs, &dbp);
1039 if (err)
1040 return (err);
1041
1042 for (i = 0; i < numbufs; i++) {
1043 int tocpy, didcpy, bufoff;
1044 dmu_buf_t *db = dbp[i];
1045
1046 bufoff = offset - db->db_offset;
1047 ASSERT3S(bufoff, >=, 0);
1048
1049 tocpy = (int)MIN(db->db_size - bufoff, size);
1050 if (tocpy == 0)
1051 break;
1052
1053 err = dmu_req_copy(db->db_data + bufoff, tocpy, &didcpy, req);
1054
1055 if (didcpy < tocpy)
1056 err = EIO;
1057
1058 if (err)
1059 break;
1060
1061 size -= tocpy;
1062 offset += didcpy;
1063 err = 0;
1064 }
1065 dmu_buf_rele_array(dbp, numbufs, FTAG);
1066
1067 return (err);
1068 }
1069
1070 int
1071 dmu_write_req(objset_t *os, uint64_t object, struct request *req, dmu_tx_t *tx)
1072 {
1073 uint64_t size = blk_rq_bytes(req);
1074 uint64_t offset = blk_rq_pos(req) << 9;
1075 dmu_buf_t **dbp;
1076 int numbufs;
1077 int err = 0;
1078 int i;
1079
1080 if (size == 0)
1081 return (0);
1082
1083 err = dmu_buf_hold_array(os, object, offset, size, FALSE, FTAG,
1084 &numbufs, &dbp);
1085 if (err)
1086 return (err);
1087
1088 for (i = 0; i < numbufs; i++) {
1089 int tocpy, didcpy, bufoff;
1090 dmu_buf_t *db = dbp[i];
1091
1092 bufoff = offset - db->db_offset;
1093 ASSERT3S(bufoff, >=, 0);
1094
1095 tocpy = (int)MIN(db->db_size - bufoff, size);
1096 if (tocpy == 0)
1097 break;
1098
1099 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
1100
1101 if (tocpy == db->db_size)
1102 dmu_buf_will_fill(db, tx);
1103 else
1104 dmu_buf_will_dirty(db, tx);
1105
1106 err = dmu_req_copy(db->db_data + bufoff, tocpy, &didcpy, req);
1107
1108 if (tocpy == db->db_size)
1109 dmu_buf_fill_done(db, tx);
1110
1111 if (didcpy < tocpy)
1112 err = EIO;
1113
1114 if (err)
1115 break;
1116
1117 size -= tocpy;
1118 offset += didcpy;
1119 err = 0;
1120 }
1121
1122 dmu_buf_rele_array(dbp, numbufs, FTAG);
1123 return (err);
1124 }
1125 #endif
1126
1127 #ifdef HAVE_ZPL
1128 int
1129 dmu_write_uio_dbuf(dmu_buf_t *zdb, uio_t *uio, uint64_t size,
1130 dmu_tx_t *tx)
1131 {
1132 dmu_buf_impl_t *db = (dmu_buf_impl_t *)zdb;
1133 dnode_t *dn;
1134 int err;
1135
1136 if (size == 0)
1137 return (0);
1138
1139 DB_DNODE_ENTER(db);
1140 dn = DB_DNODE(db);
1141 err = dmu_write_uio_dnode(dn, uio, size, tx);
1142 DB_DNODE_EXIT(db);
1143
1144 return (err);
1145 }
1146
1147 int
1148 dmu_write_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size,
1149 dmu_tx_t *tx)
1150 {
1151 dnode_t *dn;
1152 int err;
1153
1154 if (size == 0)
1155 return (0);
1156
1157 err = dnode_hold(os, object, FTAG, &dn);
1158 if (err)
1159 return (err);
1160
1161 err = dmu_write_uio_dnode(dn, uio, size, tx);
1162
1163 dnode_rele(dn, FTAG);
1164
1165 return (err);
1166 }
1167
1168 int
1169 dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
1170 page_t *pp, dmu_tx_t *tx)
1171 {
1172 dmu_buf_t **dbp;
1173 int numbufs, i;
1174 int err;
1175
1176 if (size == 0)
1177 return (0);
1178
1179 err = dmu_buf_hold_array(os, object, offset, size,
1180 FALSE, FTAG, &numbufs, &dbp);
1181 if (err)
1182 return (err);
1183
1184 for (i = 0; i < numbufs; i++) {
1185 int tocpy, copied, thiscpy;
1186 int bufoff;
1187 dmu_buf_t *db = dbp[i];
1188 caddr_t va;
1189
1190 ASSERT(size > 0);
1191 ASSERT3U(db->db_size, >=, PAGESIZE);
1192
1193 bufoff = offset - db->db_offset;
1194 tocpy = (int)MIN(db->db_size - bufoff, size);
1195
1196 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
1197
1198 if (tocpy == db->db_size)
1199 dmu_buf_will_fill(db, tx);
1200 else
1201 dmu_buf_will_dirty(db, tx);
1202
1203 for (copied = 0; copied < tocpy; copied += PAGESIZE) {
1204 ASSERT3U(pp->p_offset, ==, db->db_offset + bufoff);
1205 thiscpy = MIN(PAGESIZE, tocpy - copied);
1206 va = zfs_map_page(pp, S_READ);
1207 bcopy(va, (char *)db->db_data + bufoff, thiscpy);
1208 zfs_unmap_page(pp, va);
1209 pp = pp->p_next;
1210 bufoff += PAGESIZE;
1211 }
1212
1213 if (tocpy == db->db_size)
1214 dmu_buf_fill_done(db, tx);
1215
1216 offset += tocpy;
1217 size -= tocpy;
1218 }
1219 dmu_buf_rele_array(dbp, numbufs, FTAG);
1220 return (err);
1221 }
1222 #endif
1223
1224 /*
1225 * Allocate a loaned anonymous arc buffer.
1226 */
1227 arc_buf_t *
1228 dmu_request_arcbuf(dmu_buf_t *handle, int size)
1229 {
1230 dmu_buf_impl_t *db = (dmu_buf_impl_t *)handle;
1231 spa_t *spa;
1232
1233 DB_GET_SPA(&spa, db);
1234 return (arc_loan_buf(spa, size));
1235 }
1236
1237 /*
1238 * Free a loaned arc buffer.
1239 */
1240 void
1241 dmu_return_arcbuf(arc_buf_t *buf)
1242 {
1243 arc_return_buf(buf, FTAG);
1244 VERIFY(arc_buf_remove_ref(buf, FTAG) == 1);
1245 }
1246
1247 /*
1248 * When possible directly assign passed loaned arc buffer to a dbuf.
1249 * If this is not possible copy the contents of passed arc buf via
1250 * dmu_write().
1251 */
1252 void
1253 dmu_assign_arcbuf(dmu_buf_t *handle, uint64_t offset, arc_buf_t *buf,
1254 dmu_tx_t *tx)
1255 {
1256 dmu_buf_impl_t *dbuf = (dmu_buf_impl_t *)handle;
1257 dnode_t *dn;
1258 dmu_buf_impl_t *db;
1259 uint32_t blksz = (uint32_t)arc_buf_size(buf);
1260 uint64_t blkid;
1261
1262 DB_DNODE_ENTER(dbuf);
1263 dn = DB_DNODE(dbuf);
1264 rw_enter(&dn->dn_struct_rwlock, RW_READER);
1265 blkid = dbuf_whichblock(dn, offset);
1266 VERIFY((db = dbuf_hold(dn, blkid, FTAG)) != NULL);
1267 rw_exit(&dn->dn_struct_rwlock);
1268 DB_DNODE_EXIT(dbuf);
1269
1270 if (offset == db->db.db_offset && blksz == db->db.db_size) {
1271 dbuf_assign_arcbuf(db, buf, tx);
1272 dbuf_rele(db, FTAG);
1273 } else {
1274 objset_t *os;
1275 uint64_t object;
1276
1277 DB_DNODE_ENTER(dbuf);
1278 dn = DB_DNODE(dbuf);
1279 os = dn->dn_objset;
1280 object = dn->dn_object;
1281 DB_DNODE_EXIT(dbuf);
1282
1283 dbuf_rele(db, FTAG);
1284 dmu_write(os, object, offset, blksz, buf->b_data, tx);
1285 dmu_return_arcbuf(buf);
1286 XUIOSTAT_BUMP(xuiostat_wbuf_copied);
1287 }
1288 }
1289
1290 typedef struct {
1291 dbuf_dirty_record_t *dsa_dr;
1292 dmu_sync_cb_t *dsa_done;
1293 zgd_t *dsa_zgd;
1294 dmu_tx_t *dsa_tx;
1295 } dmu_sync_arg_t;
1296
1297 /* ARGSUSED */
1298 static void
1299 dmu_sync_ready(zio_t *zio, arc_buf_t *buf, void *varg)
1300 {
1301 dmu_sync_arg_t *dsa = varg;
1302 dmu_buf_t *db = dsa->dsa_zgd->zgd_db;
1303 blkptr_t *bp = zio->io_bp;
1304
1305 if (zio->io_error == 0) {
1306 if (BP_IS_HOLE(bp)) {
1307 /*
1308 * A block of zeros may compress to a hole, but the
1309 * block size still needs to be known for replay.
1310 */
1311 BP_SET_LSIZE(bp, db->db_size);
1312 } else {
1313 ASSERT(BP_GET_LEVEL(bp) == 0);
1314 bp->blk_fill = 1;
1315 }
1316 }
1317 }
1318
1319 static void
1320 dmu_sync_late_arrival_ready(zio_t *zio)
1321 {
1322 dmu_sync_ready(zio, NULL, zio->io_private);
1323 }
1324
1325 /* ARGSUSED */
1326 static void
1327 dmu_sync_done(zio_t *zio, arc_buf_t *buf, void *varg)
1328 {
1329 dmu_sync_arg_t *dsa = varg;
1330 dbuf_dirty_record_t *dr = dsa->dsa_dr;
1331 dmu_buf_impl_t *db = dr->dr_dbuf;
1332
1333 mutex_enter(&db->db_mtx);
1334 ASSERT(dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC);
1335 if (zio->io_error == 0) {
1336 dr->dt.dl.dr_overridden_by = *zio->io_bp;
1337 dr->dt.dl.dr_override_state = DR_OVERRIDDEN;
1338 dr->dt.dl.dr_copies = zio->io_prop.zp_copies;
1339 if (BP_IS_HOLE(&dr->dt.dl.dr_overridden_by))
1340 BP_ZERO(&dr->dt.dl.dr_overridden_by);
1341 } else {
1342 dr->dt.dl.dr_override_state = DR_NOT_OVERRIDDEN;
1343 }
1344 cv_broadcast(&db->db_changed);
1345 mutex_exit(&db->db_mtx);
1346
1347 dsa->dsa_done(dsa->dsa_zgd, zio->io_error);
1348
1349 kmem_free(dsa, sizeof (*dsa));
1350 }
1351
1352 static void
1353 dmu_sync_late_arrival_done(zio_t *zio)
1354 {
1355 blkptr_t *bp = zio->io_bp;
1356 dmu_sync_arg_t *dsa = zio->io_private;
1357
1358 if (zio->io_error == 0 && !BP_IS_HOLE(bp)) {
1359 ASSERT(zio->io_bp->blk_birth == zio->io_txg);
1360 ASSERT(zio->io_txg > spa_syncing_txg(zio->io_spa));
1361 zio_free(zio->io_spa, zio->io_txg, zio->io_bp);
1362 }
1363
1364 dmu_tx_commit(dsa->dsa_tx);
1365
1366 dsa->dsa_done(dsa->dsa_zgd, zio->io_error);
1367
1368 kmem_free(dsa, sizeof (*dsa));
1369 }
1370
1371 static int
1372 dmu_sync_late_arrival(zio_t *pio, objset_t *os, dmu_sync_cb_t *done, zgd_t *zgd,
1373 zio_prop_t *zp, zbookmark_t *zb)
1374 {
1375 dmu_sync_arg_t *dsa;
1376 dmu_tx_t *tx;
1377
1378 tx = dmu_tx_create(os);
1379 dmu_tx_hold_space(tx, zgd->zgd_db->db_size);
1380 if (dmu_tx_assign(tx, TXG_WAIT) != 0) {
1381 dmu_tx_abort(tx);
1382 return (EIO); /* Make zl_get_data do txg_waited_synced() */
1383 }
1384
1385 dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP);
1386 dsa->dsa_dr = NULL;
1387 dsa->dsa_done = done;
1388 dsa->dsa_zgd = zgd;
1389 dsa->dsa_tx = tx;
1390
1391 zio_nowait(zio_write(pio, os->os_spa, dmu_tx_get_txg(tx), zgd->zgd_bp,
1392 zgd->zgd_db->db_data, zgd->zgd_db->db_size, zp,
1393 dmu_sync_late_arrival_ready, dmu_sync_late_arrival_done, dsa,
1394 ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL, zb));
1395
1396 return (0);
1397 }
1398
1399 /*
1400 * Intent log support: sync the block associated with db to disk.
1401 * N.B. and XXX: the caller is responsible for making sure that the
1402 * data isn't changing while dmu_sync() is writing it.
1403 *
1404 * Return values:
1405 *
1406 * EEXIST: this txg has already been synced, so there's nothing to to.
1407 * The caller should not log the write.
1408 *
1409 * ENOENT: the block was dbuf_free_range()'d, so there's nothing to do.
1410 * The caller should not log the write.
1411 *
1412 * EALREADY: this block is already in the process of being synced.
1413 * The caller should track its progress (somehow).
1414 *
1415 * EIO: could not do the I/O.
1416 * The caller should do a txg_wait_synced().
1417 *
1418 * 0: the I/O has been initiated.
1419 * The caller should log this blkptr in the done callback.
1420 * It is possible that the I/O will fail, in which case
1421 * the error will be reported to the done callback and
1422 * propagated to pio from zio_done().
1423 */
1424 int
1425 dmu_sync(zio_t *pio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd)
1426 {
1427 blkptr_t *bp = zgd->zgd_bp;
1428 dmu_buf_impl_t *db = (dmu_buf_impl_t *)zgd->zgd_db;
1429 objset_t *os = db->db_objset;
1430 dsl_dataset_t *ds = os->os_dsl_dataset;
1431 dbuf_dirty_record_t *dr;
1432 dmu_sync_arg_t *dsa;
1433 zbookmark_t zb;
1434 zio_prop_t zp;
1435 dnode_t *dn;
1436
1437 ASSERT(pio != NULL);
1438 ASSERT(BP_IS_HOLE(bp));
1439 ASSERT(txg != 0);
1440
1441 SET_BOOKMARK(&zb, ds->ds_object,
1442 db->db.db_object, db->db_level, db->db_blkid);
1443
1444 DB_DNODE_ENTER(db);
1445 dn = DB_DNODE(db);
1446 dmu_write_policy(os, dn, db->db_level, WP_DMU_SYNC, &zp);
1447 DB_DNODE_EXIT(db);
1448
1449 /*
1450 * If we're frozen (running ziltest), we always need to generate a bp.
1451 */
1452 if (txg > spa_freeze_txg(os->os_spa))
1453 return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb));
1454
1455 /*
1456 * Grabbing db_mtx now provides a barrier between dbuf_sync_leaf()
1457 * and us. If we determine that this txg is not yet syncing,
1458 * but it begins to sync a moment later, that's OK because the
1459 * sync thread will block in dbuf_sync_leaf() until we drop db_mtx.
1460 */
1461 mutex_enter(&db->db_mtx);
1462
1463 if (txg <= spa_last_synced_txg(os->os_spa)) {
1464 /*
1465 * This txg has already synced. There's nothing to do.
1466 */
1467 mutex_exit(&db->db_mtx);
1468 return (EEXIST);
1469 }
1470
1471 if (txg <= spa_syncing_txg(os->os_spa)) {
1472 /*
1473 * This txg is currently syncing, so we can't mess with
1474 * the dirty record anymore; just write a new log block.
1475 */
1476 mutex_exit(&db->db_mtx);
1477 return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb));
1478 }
1479
1480 dr = db->db_last_dirty;
1481 while (dr && dr->dr_txg != txg)
1482 dr = dr->dr_next;
1483
1484 if (dr == NULL) {
1485 /*
1486 * There's no dr for this dbuf, so it must have been freed.
1487 * There's no need to log writes to freed blocks, so we're done.
1488 */
1489 mutex_exit(&db->db_mtx);
1490 return (ENOENT);
1491 }
1492
1493 ASSERT(dr->dr_txg == txg);
1494 if (dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC ||
1495 dr->dt.dl.dr_override_state == DR_OVERRIDDEN) {
1496 /*
1497 * We have already issued a sync write for this buffer,
1498 * or this buffer has already been synced. It could not
1499 * have been dirtied since, or we would have cleared the state.
1500 */
1501 mutex_exit(&db->db_mtx);
1502 return (EALREADY);
1503 }
1504
1505 ASSERT(dr->dt.dl.dr_override_state == DR_NOT_OVERRIDDEN);
1506 dr->dt.dl.dr_override_state = DR_IN_DMU_SYNC;
1507 mutex_exit(&db->db_mtx);
1508
1509 dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP);
1510 dsa->dsa_dr = dr;
1511 dsa->dsa_done = done;
1512 dsa->dsa_zgd = zgd;
1513 dsa->dsa_tx = NULL;
1514
1515 zio_nowait(arc_write(pio, os->os_spa, txg,
1516 bp, dr->dt.dl.dr_data, DBUF_IS_L2CACHEABLE(db), &zp,
1517 dmu_sync_ready, dmu_sync_done, dsa,
1518 ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL, &zb));
1519
1520 return (0);
1521 }
1522
1523 int
1524 dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, int ibs,
1525 dmu_tx_t *tx)
1526 {
1527 dnode_t *dn;
1528 int err;
1529
1530 err = dnode_hold(os, object, FTAG, &dn);
1531 if (err)
1532 return (err);
1533 err = dnode_set_blksz(dn, size, ibs, tx);
1534 dnode_rele(dn, FTAG);
1535 return (err);
1536 }
1537
1538 void
1539 dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum,
1540 dmu_tx_t *tx)
1541 {
1542 dnode_t *dn;
1543
1544 /* XXX assumes dnode_hold will not get an i/o error */
1545 (void) dnode_hold(os, object, FTAG, &dn);
1546 ASSERT(checksum < ZIO_CHECKSUM_FUNCTIONS);
1547 dn->dn_checksum = checksum;
1548 dnode_setdirty(dn, tx);
1549 dnode_rele(dn, FTAG);
1550 }
1551
1552 void
1553 dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress,
1554 dmu_tx_t *tx)
1555 {
1556 dnode_t *dn;
1557
1558 /* XXX assumes dnode_hold will not get an i/o error */
1559 (void) dnode_hold(os, object, FTAG, &dn);
1560 ASSERT(compress < ZIO_COMPRESS_FUNCTIONS);
1561 dn->dn_compress = compress;
1562 dnode_setdirty(dn, tx);
1563 dnode_rele(dn, FTAG);
1564 }
1565
1566 int zfs_mdcomp_disable = 0;
1567
1568 void
1569 dmu_write_policy(objset_t *os, dnode_t *dn, int level, int wp, zio_prop_t *zp)
1570 {
1571 dmu_object_type_t type = dn ? dn->dn_type : DMU_OT_OBJSET;
1572 boolean_t ismd = (level > 0 || dmu_ot[type].ot_metadata ||
1573 (wp & WP_SPILL));
1574 enum zio_checksum checksum = os->os_checksum;
1575 enum zio_compress compress = os->os_compress;
1576 enum zio_checksum dedup_checksum = os->os_dedup_checksum;
1577 boolean_t dedup;
1578 boolean_t dedup_verify = os->os_dedup_verify;
1579 int copies = os->os_copies;
1580
1581 /*
1582 * Determine checksum setting.
1583 */
1584 if (ismd) {
1585 /*
1586 * Metadata always gets checksummed. If the data
1587 * checksum is multi-bit correctable, and it's not a
1588 * ZBT-style checksum, then it's suitable for metadata
1589 * as well. Otherwise, the metadata checksum defaults
1590 * to fletcher4.
1591 */
1592 if (zio_checksum_table[checksum].ci_correctable < 1 ||
1593 zio_checksum_table[checksum].ci_eck)
1594 checksum = ZIO_CHECKSUM_FLETCHER_4;
1595 } else {
1596 checksum = zio_checksum_select(dn->dn_checksum, checksum);
1597 }
1598
1599 /*
1600 * Determine compression setting.
1601 */
1602 if (ismd) {
1603 /*
1604 * XXX -- we should design a compression algorithm
1605 * that specializes in arrays of bps.
1606 */
1607 compress = zfs_mdcomp_disable ? ZIO_COMPRESS_EMPTY :
1608 ZIO_COMPRESS_LZJB;
1609 } else {
1610 compress = zio_compress_select(dn->dn_compress, compress);
1611 }
1612
1613 /*
1614 * Determine dedup setting. If we are in dmu_sync(), we won't
1615 * actually dedup now because that's all done in syncing context;
1616 * but we do want to use the dedup checkum. If the checksum is not
1617 * strong enough to ensure unique signatures, force dedup_verify.
1618 */
1619 dedup = (!ismd && dedup_checksum != ZIO_CHECKSUM_OFF);
1620 if (dedup) {
1621 checksum = dedup_checksum;
1622 if (!zio_checksum_table[checksum].ci_dedup)
1623 dedup_verify = 1;
1624 }
1625
1626 if (wp & WP_DMU_SYNC)
1627 dedup = 0;
1628
1629 if (wp & WP_NOFILL) {
1630 ASSERT(!ismd && level == 0);
1631 checksum = ZIO_CHECKSUM_OFF;
1632 compress = ZIO_COMPRESS_OFF;
1633 dedup = B_FALSE;
1634 }
1635
1636 zp->zp_checksum = checksum;
1637 zp->zp_compress = compress;
1638 zp->zp_type = (wp & WP_SPILL) ? dn->dn_bonustype : type;
1639 zp->zp_level = level;
1640 zp->zp_copies = MIN(copies + ismd, spa_max_replication(os->os_spa));
1641 zp->zp_dedup = dedup;
1642 zp->zp_dedup_verify = dedup && dedup_verify;
1643 }
1644
1645 int
1646 dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, uint64_t *off)
1647 {
1648 dnode_t *dn;
1649 int i, err;
1650
1651 err = dnode_hold(os, object, FTAG, &dn);
1652 if (err)
1653 return (err);
1654 /*
1655 * Sync any current changes before
1656 * we go trundling through the block pointers.
1657 */
1658 for (i = 0; i < TXG_SIZE; i++) {
1659 if (list_link_active(&dn->dn_dirty_link[i]))
1660 break;
1661 }
1662 if (i != TXG_SIZE) {
1663 dnode_rele(dn, FTAG);
1664 txg_wait_synced(dmu_objset_pool(os), 0);
1665 err = dnode_hold(os, object, FTAG, &dn);
1666 if (err)
1667 return (err);
1668 }
1669
1670 err = dnode_next_offset(dn, (hole ? DNODE_FIND_HOLE : 0), off, 1, 1, 0);
1671 dnode_rele(dn, FTAG);
1672
1673 return (err);
1674 }
1675
1676 void
1677 dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi)
1678 {
1679 dnode_phys_t *dnp;
1680 int i;
1681
1682 rw_enter(&dn->dn_struct_rwlock, RW_READER);
1683 mutex_enter(&dn->dn_mtx);
1684
1685 dnp = dn->dn_phys;
1686
1687 doi->doi_data_block_size = dn->dn_datablksz;
1688 doi->doi_metadata_block_size = dn->dn_indblkshift ?
1689 1ULL << dn->dn_indblkshift : 0;
1690 doi->doi_type = dn->dn_type;
1691 doi->doi_bonus_type = dn->dn_bonustype;
1692 doi->doi_bonus_size = dn->dn_bonuslen;
1693 doi->doi_indirection = dn->dn_nlevels;
1694 doi->doi_checksum = dn->dn_checksum;
1695 doi->doi_compress = dn->dn_compress;
1696 doi->doi_physical_blocks_512 = (DN_USED_BYTES(dnp) + 256) >> 9;
1697 doi->doi_max_offset = (dnp->dn_maxblkid + 1) * dn->dn_datablksz;
1698 doi->doi_fill_count = 0;
1699 for (i = 0; i < dnp->dn_nblkptr; i++)
1700 doi->doi_fill_count += dnp->dn_blkptr[i].blk_fill;
1701
1702 mutex_exit(&dn->dn_mtx);
1703 rw_exit(&dn->dn_struct_rwlock);
1704 }
1705
1706 /*
1707 * Get information on a DMU object.
1708 * If doi is NULL, just indicates whether the object exists.
1709 */
1710 int
1711 dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi)
1712 {
1713 dnode_t *dn;
1714 int err = dnode_hold(os, object, FTAG, &dn);
1715
1716 if (err)
1717 return (err);
1718
1719 if (doi != NULL)
1720 dmu_object_info_from_dnode(dn, doi);
1721
1722 dnode_rele(dn, FTAG);
1723 return (0);
1724 }
1725
1726 /*
1727 * As above, but faster; can be used when you have a held dbuf in hand.
1728 */
1729 void
1730 dmu_object_info_from_db(dmu_buf_t *db_fake, dmu_object_info_t *doi)
1731 {
1732 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
1733
1734 DB_DNODE_ENTER(db);
1735 dmu_object_info_from_dnode(DB_DNODE(db), doi);
1736 DB_DNODE_EXIT(db);
1737 }
1738
1739 /*
1740 * Faster still when you only care about the size.
1741 * This is specifically optimized for zfs_getattr().
1742 */
1743 void
1744 dmu_object_size_from_db(dmu_buf_t *db_fake, uint32_t *blksize,
1745 u_longlong_t *nblk512)
1746 {
1747 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
1748 dnode_t *dn;
1749
1750 DB_DNODE_ENTER(db);
1751 dn = DB_DNODE(db);
1752
1753 *blksize = dn->dn_datablksz;
1754 /* add 1 for dnode space */
1755 *nblk512 = ((DN_USED_BYTES(dn->dn_phys) + SPA_MINBLOCKSIZE/2) >>
1756 SPA_MINBLOCKSHIFT) + 1;
1757 DB_DNODE_EXIT(db);
1758 }
1759
1760 void
1761 byteswap_uint64_array(void *vbuf, size_t size)
1762 {
1763 uint64_t *buf = vbuf;
1764 size_t count = size >> 3;
1765 int i;
1766
1767 ASSERT((size & 7) == 0);
1768
1769 for (i = 0; i < count; i++)
1770 buf[i] = BSWAP_64(buf[i]);
1771 }
1772
1773 void
1774 byteswap_uint32_array(void *vbuf, size_t size)
1775 {
1776 uint32_t *buf = vbuf;
1777 size_t count = size >> 2;
1778 int i;
1779
1780 ASSERT((size & 3) == 0);
1781
1782 for (i = 0; i < count; i++)
1783 buf[i] = BSWAP_32(buf[i]);
1784 }
1785
1786 void
1787 byteswap_uint16_array(void *vbuf, size_t size)
1788 {
1789 uint16_t *buf = vbuf;
1790 size_t count = size >> 1;
1791 int i;
1792
1793 ASSERT((size & 1) == 0);
1794
1795 for (i = 0; i < count; i++)
1796 buf[i] = BSWAP_16(buf[i]);
1797 }
1798
1799 /* ARGSUSED */
1800 void
1801 byteswap_uint8_array(void *vbuf, size_t size)
1802 {
1803 }
1804
1805 void
1806 dmu_init(void)
1807 {
1808 zfs_dbgmsg_init();
1809 sa_cache_init();
1810 xuio_stat_init();
1811 dmu_objset_init();
1812 dnode_init();
1813 dbuf_init();
1814 zfetch_init();
1815 arc_init();
1816 l2arc_init();
1817 }
1818
1819 void
1820 dmu_fini(void)
1821 {
1822 l2arc_fini();
1823 arc_fini();
1824 zfetch_fini();
1825 dbuf_fini();
1826 dnode_fini();
1827 dmu_objset_fini();
1828 xuio_stat_fini();
1829 sa_cache_fini();
1830 zfs_dbgmsg_fini();
1831 }
1832
1833 #if defined(_KERNEL) && defined(HAVE_SPL)
1834 EXPORT_SYMBOL(dmu_bonus_hold);
1835 EXPORT_SYMBOL(dmu_free_range);
1836 EXPORT_SYMBOL(dmu_read);
1837 EXPORT_SYMBOL(dmu_write);
1838
1839 /* Get information on a DMU object. */
1840 EXPORT_SYMBOL(dmu_object_info);
1841 EXPORT_SYMBOL(dmu_object_info_from_dnode);
1842 EXPORT_SYMBOL(dmu_object_info_from_db);
1843 EXPORT_SYMBOL(dmu_object_size_from_db);
1844
1845 EXPORT_SYMBOL(dmu_object_set_blocksize);
1846 EXPORT_SYMBOL(dmu_object_set_checksum);
1847 EXPORT_SYMBOL(dmu_object_set_compress);
1848
1849 EXPORT_SYMBOL(dmu_ot);
1850 #endif
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