]> git.proxmox.com Git - mirror_zfs.git/blob - module/zfs/dmu.c
projects / mirror_zfs.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Rebase master to b121
[mirror_zfs.git] / module / zfs / dmu.c
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 2009 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26 #include <sys/dmu.h>
27 #include <sys/dmu_impl.h>
28 #include <sys/dmu_tx.h>
29 #include <sys/dbuf.h>
30 #include <sys/dnode.h>
31 #include <sys/zfs_context.h>
32 #include <sys/dmu_objset.h>
33 #include <sys/dmu_traverse.h>
34 #include <sys/dsl_dataset.h>
35 #include <sys/dsl_dir.h>
36 #include <sys/dsl_pool.h>
37 #include <sys/dsl_synctask.h>
38 #include <sys/dsl_prop.h>
39 #include <sys/dmu_zfetch.h>
40 #include <sys/zfs_ioctl.h>
41 #include <sys/zap.h>
42 #include <sys/zio_checksum.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, "bplist" },
55 { byteswap_uint64_array, TRUE, "bplist 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, "scrub 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 };
92
93 int
94 dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset,
95 void *tag, dmu_buf_t **dbp)
96 {
97 dnode_t *dn;
98 uint64_t blkid;
99 dmu_buf_impl_t *db;
100 int err;
101
102 err = dnode_hold(os->os, object, FTAG, &dn);
103 if (err)
104 return (err);
105 blkid = dbuf_whichblock(dn, offset);
106 rw_enter(&dn->dn_struct_rwlock, RW_READER);
107 db = dbuf_hold(dn, blkid, tag);
108 rw_exit(&dn->dn_struct_rwlock);
109 if (db == NULL) {
110 err = EIO;
111 } else {
112 err = dbuf_read(db, NULL, DB_RF_CANFAIL);
113 if (err) {
114 dbuf_rele(db, tag);
115 db = NULL;
116 }
117 }
118
119 dnode_rele(dn, FTAG);
120 *dbp = &db->db;
121 return (err);
122 }
123
124 int
125 dmu_bonus_max(void)
126 {
127 return (DN_MAX_BONUSLEN);
128 }
129
130 int
131 dmu_set_bonus(dmu_buf_t *db, int newsize, dmu_tx_t *tx)
132 {
133 dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode;
134
135 if (dn->dn_bonus != (dmu_buf_impl_t *)db)
136 return (EINVAL);
137 if (newsize < 0 || newsize > db->db_size)
138 return (EINVAL);
139 dnode_setbonuslen(dn, newsize, tx);
140 return (0);
141 }
142
143 /*
144 * returns ENOENT, EIO, or 0.
145 */
146 int
147 dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **dbp)
148 {
149 dnode_t *dn;
150 dmu_buf_impl_t *db;
151 int error;
152
153 error = dnode_hold(os->os, object, FTAG, &dn);
154 if (error)
155 return (error);
156
157 rw_enter(&dn->dn_struct_rwlock, RW_READER);
158 if (dn->dn_bonus == NULL) {
159 rw_exit(&dn->dn_struct_rwlock);
160 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
161 if (dn->dn_bonus == NULL)
162 dbuf_create_bonus(dn);
163 }
164 db = dn->dn_bonus;
165 rw_exit(&dn->dn_struct_rwlock);
166
167 /* as long as the bonus buf is held, the dnode will be held */
168 if (refcount_add(&db->db_holds, tag) == 1)
169 VERIFY(dnode_add_ref(dn, db));
170
171 dnode_rele(dn, FTAG);
172
173 VERIFY(0 == dbuf_read(db, NULL, DB_RF_MUST_SUCCEED));
174
175 *dbp = &db->db;
176 return (0);
177 }
178
179 /*
180 * Note: longer-term, we should modify all of the dmu_buf_*() interfaces
181 * to take a held dnode rather than <os, object> -- the lookup is wasteful,
182 * and can induce severe lock contention when writing to several files
183 * whose dnodes are in the same block.
184 */
185 static int
186 dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset, uint64_t length,
187 int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp, uint32_t flags)
188 {
189 dsl_pool_t *dp = NULL;
190 dmu_buf_t **dbp;
191 uint64_t blkid, nblks, i;
192 uint32_t dbuf_flags;
193 int err;
194 zio_t *zio;
195 hrtime_t start;
196
197 ASSERT(length <= DMU_MAX_ACCESS);
198
199 dbuf_flags = DB_RF_CANFAIL | DB_RF_NEVERWAIT | DB_RF_HAVESTRUCT;
200 if (flags & DMU_READ_NO_PREFETCH || length > zfetch_array_rd_sz)
201 dbuf_flags |= DB_RF_NOPREFETCH;
202
203 rw_enter(&dn->dn_struct_rwlock, RW_READER);
204 if (dn->dn_datablkshift) {
205 int blkshift = dn->dn_datablkshift;
206 nblks = (P2ROUNDUP(offset+length, 1ULL<<blkshift) -
207 P2ALIGN(offset, 1ULL<<blkshift)) >> blkshift;
208 } else {
209 if (offset + length > dn->dn_datablksz) {
210 zfs_panic_recover("zfs: accessing past end of object "
211 "%llx/%llx (size=%u access=%llu+%llu)",
212 (longlong_t)dn->dn_objset->
213 os_dsl_dataset->ds_object,
214 (longlong_t)dn->dn_object, dn->dn_datablksz,
215 (longlong_t)offset, (longlong_t)length);
216 rw_exit(&dn->dn_struct_rwlock);
217 return (EIO);
218 }
219 nblks = 1;
220 }
221 dbp = kmem_zalloc(sizeof (dmu_buf_t *) * nblks, KM_SLEEP);
222
223 if (dn->dn_objset->os_dsl_dataset)
224 dp = dn->dn_objset->os_dsl_dataset->ds_dir->dd_pool;
225 if (dp && dsl_pool_sync_context(dp))
226 start = gethrtime();
227 zio = zio_root(dn->dn_objset->os_spa, NULL, NULL, ZIO_FLAG_CANFAIL);
228 blkid = dbuf_whichblock(dn, offset);
229 for (i = 0; i < nblks; i++) {
230 dmu_buf_impl_t *db = dbuf_hold(dn, blkid+i, tag);
231 if (db == NULL) {
232 rw_exit(&dn->dn_struct_rwlock);
233 dmu_buf_rele_array(dbp, nblks, tag);
234 zio_nowait(zio);
235 return (EIO);
236 }
237 /* initiate async i/o */
238 if (read) {
239 (void) dbuf_read(db, zio, dbuf_flags);
240 }
241 dbp[i] = &db->db;
242 }
243 rw_exit(&dn->dn_struct_rwlock);
244
245 /* wait for async i/o */
246 err = zio_wait(zio);
247 /* track read overhead when we are in sync context */
248 if (dp && dsl_pool_sync_context(dp))
249 dp->dp_read_overhead += gethrtime() - start;
250 if (err) {
251 dmu_buf_rele_array(dbp, nblks, tag);
252 return (err);
253 }
254
255 /* wait for other io to complete */
256 if (read) {
257 for (i = 0; i < nblks; i++) {
258 dmu_buf_impl_t *db = (dmu_buf_impl_t *)dbp[i];
259 mutex_enter(&db->db_mtx);
260 while (db->db_state == DB_READ ||
261 db->db_state == DB_FILL)
262 cv_wait(&db->db_changed, &db->db_mtx);
263 if (db->db_state == DB_UNCACHED)
264 err = EIO;
265 mutex_exit(&db->db_mtx);
266 if (err) {
267 dmu_buf_rele_array(dbp, nblks, tag);
268 return (err);
269 }
270 }
271 }
272
273 *numbufsp = nblks;
274 *dbpp = dbp;
275 return (0);
276 }
277
278 static int
279 dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset,
280 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp)
281 {
282 dnode_t *dn;
283 int err;
284
285 err = dnode_hold(os->os, object, FTAG, &dn);
286 if (err)
287 return (err);
288
289 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag,
290 numbufsp, dbpp, DMU_READ_PREFETCH);
291
292 dnode_rele(dn, FTAG);
293
294 return (err);
295 }
296
297 int
298 dmu_buf_hold_array_by_bonus(dmu_buf_t *db, uint64_t offset,
299 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp)
300 {
301 dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode;
302 int err;
303
304 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag,
305 numbufsp, dbpp, DMU_READ_PREFETCH);
306
307 return (err);
308 }
309
310 void
311 dmu_buf_rele_array(dmu_buf_t **dbp_fake, int numbufs, void *tag)
312 {
313 int i;
314 dmu_buf_impl_t **dbp = (dmu_buf_impl_t **)dbp_fake;
315
316 if (numbufs == 0)
317 return;
318
319 for (i = 0; i < numbufs; i++) {
320 if (dbp[i])
321 dbuf_rele(dbp[i], tag);
322 }
323
324 kmem_free(dbp, sizeof (dmu_buf_t *) * numbufs);
325 }
326
327 void
328 dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, uint64_t len)
329 {
330 dnode_t *dn;
331 uint64_t blkid;
332 int nblks, i, err;
333
334 if (zfs_prefetch_disable)
335 return;
336
337 if (len == 0) { /* they're interested in the bonus buffer */
338 dn = os->os->os_meta_dnode;
339
340 if (object == 0 || object >= DN_MAX_OBJECT)
341 return;
342
343 rw_enter(&dn->dn_struct_rwlock, RW_READER);
344 blkid = dbuf_whichblock(dn, object * sizeof (dnode_phys_t));
345 dbuf_prefetch(dn, blkid);
346 rw_exit(&dn->dn_struct_rwlock);
347 return;
348 }
349
350 /*
351 * XXX - Note, if the dnode for the requested object is not
352 * already cached, we will do a *synchronous* read in the
353 * dnode_hold() call. The same is true for any indirects.
354 */
355 err = dnode_hold(os->os, object, FTAG, &dn);
356 if (err != 0)
357 return;
358
359 rw_enter(&dn->dn_struct_rwlock, RW_READER);
360 if (dn->dn_datablkshift) {
361 int blkshift = dn->dn_datablkshift;
362 nblks = (P2ROUNDUP(offset+len, 1<<blkshift) -
363 P2ALIGN(offset, 1<<blkshift)) >> blkshift;
364 } else {
365 nblks = (offset < dn->dn_datablksz);
366 }
367
368 if (nblks != 0) {
369 blkid = dbuf_whichblock(dn, offset);
370 for (i = 0; i < nblks; i++)
371 dbuf_prefetch(dn, blkid+i);
372 }
373
374 rw_exit(&dn->dn_struct_rwlock);
375
376 dnode_rele(dn, FTAG);
377 }
378
379 /*
380 * Get the next "chunk" of file data to free. We traverse the file from
381 * the end so that the file gets shorter over time (if we crashes in the
382 * middle, this will leave us in a better state). We find allocated file
383 * data by simply searching the allocated level 1 indirects.
384 */
385 static int
386 get_next_chunk(dnode_t *dn, uint64_t *start, uint64_t limit)
387 {
388 uint64_t len = *start - limit;
389 uint64_t blkcnt = 0;
390 uint64_t maxblks = DMU_MAX_ACCESS / (1ULL << (dn->dn_indblkshift + 1));
391 uint64_t iblkrange =
392 dn->dn_datablksz * EPB(dn->dn_indblkshift, SPA_BLKPTRSHIFT);
393
394 ASSERT(limit <= *start);
395
396 if (len <= iblkrange * maxblks) {
397 *start = limit;
398 return (0);
399 }
400 ASSERT(ISP2(iblkrange));
401
402 while (*start > limit && blkcnt < maxblks) {
403 int err;
404
405 /* find next allocated L1 indirect */
406 err = dnode_next_offset(dn,
407 DNODE_FIND_BACKWARDS, start, 2, 1, 0);
408
409 /* if there are no more, then we are done */
410 if (err == ESRCH) {
411 *start = limit;
412 return (0);
413 } else if (err) {
414 return (err);
415 }
416 blkcnt += 1;
417
418 /* reset offset to end of "next" block back */
419 *start = P2ALIGN(*start, iblkrange);
420 if (*start <= limit)
421 *start = limit;
422 else
423 *start -= 1;
424 }
425 return (0);
426 }
427
428 static int
429 dmu_free_long_range_impl(objset_t *os, dnode_t *dn, uint64_t offset,
430 uint64_t length, boolean_t free_dnode)
431 {
432 dmu_tx_t *tx;
433 uint64_t object_size, start, end, len;
434 boolean_t trunc = (length == DMU_OBJECT_END);
435 int align, err;
436
437 align = 1 << dn->dn_datablkshift;
438 ASSERT(align > 0);
439 object_size = align == 1 ? dn->dn_datablksz :
440 (dn->dn_maxblkid + 1) << dn->dn_datablkshift;
441
442 end = offset + length;
443 if (trunc || end > object_size)
444 end = object_size;
445 if (end <= offset)
446 return (0);
447 length = end - offset;
448
449 while (length) {
450 start = end;
451 /* assert(offset <= start) */
452 err = get_next_chunk(dn, &start, offset);
453 if (err)
454 return (err);
455 len = trunc ? DMU_OBJECT_END : end - start;
456
457 tx = dmu_tx_create(os);
458 dmu_tx_hold_free(tx, dn->dn_object, start, len);
459 err = dmu_tx_assign(tx, TXG_WAIT);
460 if (err) {
461 dmu_tx_abort(tx);
462 return (err);
463 }
464
465 dnode_free_range(dn, start, trunc ? -1 : len, tx);
466
467 if (start == 0 && free_dnode) {
468 ASSERT(trunc);
469 dnode_free(dn, tx);
470 }
471
472 length -= end - start;
473
474 dmu_tx_commit(tx);
475 end = start;
476 }
477 return (0);
478 }
479
480 int
481 dmu_free_long_range(objset_t *os, uint64_t object,
482 uint64_t offset, uint64_t length)
483 {
484 dnode_t *dn;
485 int err;
486
487 err = dnode_hold(os->os, object, FTAG, &dn);
488 if (err != 0)
489 return (err);
490 err = dmu_free_long_range_impl(os, dn, offset, length, FALSE);
491 dnode_rele(dn, FTAG);
492 return (err);
493 }
494
495 int
496 dmu_free_object(objset_t *os, uint64_t object)
497 {
498 dnode_t *dn;
499 dmu_tx_t *tx;
500 int err;
501
502 err = dnode_hold_impl(os->os, object, DNODE_MUST_BE_ALLOCATED,
503 FTAG, &dn);
504 if (err != 0)
505 return (err);
506 if (dn->dn_nlevels == 1) {
507 tx = dmu_tx_create(os);
508 dmu_tx_hold_bonus(tx, object);
509 dmu_tx_hold_free(tx, dn->dn_object, 0, DMU_OBJECT_END);
510 err = dmu_tx_assign(tx, TXG_WAIT);
511 if (err == 0) {
512 dnode_free_range(dn, 0, DMU_OBJECT_END, tx);
513 dnode_free(dn, tx);
514 dmu_tx_commit(tx);
515 } else {
516 dmu_tx_abort(tx);
517 }
518 } else {
519 err = dmu_free_long_range_impl(os, dn, 0, DMU_OBJECT_END, TRUE);
520 }
521 dnode_rele(dn, FTAG);
522 return (err);
523 }
524
525 int
526 dmu_free_range(objset_t *os, uint64_t object, uint64_t offset,
527 uint64_t size, dmu_tx_t *tx)
528 {
529 dnode_t *dn;
530 int err = dnode_hold(os->os, object, FTAG, &dn);
531 if (err)
532 return (err);
533 ASSERT(offset < UINT64_MAX);
534 ASSERT(size == -1ULL || size <= UINT64_MAX - offset);
535 dnode_free_range(dn, offset, size, tx);
536 dnode_rele(dn, FTAG);
537 return (0);
538 }
539
540 int
541 dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
542 void *buf, uint32_t flags)
543 {
544 dnode_t *dn;
545 dmu_buf_t **dbp;
546 int numbufs, err;
547
548 err = dnode_hold(os->os, object, FTAG, &dn);
549 if (err)
550 return (err);
551
552 /*
553 * Deal with odd block sizes, where there can't be data past the first
554 * block. If we ever do the tail block optimization, we will need to
555 * handle that here as well.
556 */
557 if (dn->dn_maxblkid == 0) {
558 int newsz = offset > dn->dn_datablksz ? 0 :
559 MIN(size, dn->dn_datablksz - offset);
560 bzero((char *)buf + newsz, size - newsz);
561 size = newsz;
562 }
563
564 while (size > 0) {
565 uint64_t mylen = MIN(size, DMU_MAX_ACCESS / 2);
566 int i;
567
568 /*
569 * NB: we could do this block-at-a-time, but it's nice
570 * to be reading in parallel.
571 */
572 err = dmu_buf_hold_array_by_dnode(dn, offset, mylen,
573 TRUE, FTAG, &numbufs, &dbp, flags);
574 if (err)
575 break;
576
577 for (i = 0; i < numbufs; i++) {
578 int tocpy;
579 int bufoff;
580 dmu_buf_t *db = dbp[i];
581
582 ASSERT(size > 0);
583
584 bufoff = offset - db->db_offset;
585 tocpy = (int)MIN(db->db_size - bufoff, size);
586
587 bcopy((char *)db->db_data + bufoff, buf, tocpy);
588
589 offset += tocpy;
590 size -= tocpy;
591 buf = (char *)buf + tocpy;
592 }
593 dmu_buf_rele_array(dbp, numbufs, FTAG);
594 }
595 dnode_rele(dn, FTAG);
596 return (err);
597 }
598
599 void
600 dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
601 const void *buf, dmu_tx_t *tx)
602 {
603 dmu_buf_t **dbp;
604 int numbufs, i;
605
606 if (size == 0)
607 return;
608
609 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size,
610 FALSE, FTAG, &numbufs, &dbp));
611
612 for (i = 0; i < numbufs; i++) {
613 int tocpy;
614 int bufoff;
615 dmu_buf_t *db = dbp[i];
616
617 ASSERT(size > 0);
618
619 bufoff = offset - db->db_offset;
620 tocpy = (int)MIN(db->db_size - bufoff, size);
621
622 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
623
624 if (tocpy == db->db_size)
625 dmu_buf_will_fill(db, tx);
626 else
627 dmu_buf_will_dirty(db, tx);
628
629 bcopy(buf, (char *)db->db_data + bufoff, tocpy);
630
631 if (tocpy == db->db_size)
632 dmu_buf_fill_done(db, tx);
633
634 offset += tocpy;
635 size -= tocpy;
636 buf = (char *)buf + tocpy;
637 }
638 dmu_buf_rele_array(dbp, numbufs, FTAG);
639 }
640
641 void
642 dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
643 dmu_tx_t *tx)
644 {
645 dmu_buf_t **dbp;
646 int numbufs, i;
647
648 if (size == 0)
649 return;
650
651 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size,
652 FALSE, FTAG, &numbufs, &dbp));
653
654 for (i = 0; i < numbufs; i++) {
655 dmu_buf_t *db = dbp[i];
656
657 dmu_buf_will_not_fill(db, tx);
658 }
659 dmu_buf_rele_array(dbp, numbufs, FTAG);
660 }
661
662 #ifdef _KERNEL
663 int
664 dmu_read_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size)
665 {
666 dmu_buf_t **dbp;
667 int numbufs, i, err;
668
669 /*
670 * NB: we could do this block-at-a-time, but it's nice
671 * to be reading in parallel.
672 */
673 err = dmu_buf_hold_array(os, object, uio->uio_loffset, size, TRUE, FTAG,
674 &numbufs, &dbp);
675 if (err)
676 return (err);
677
678 for (i = 0; i < numbufs; i++) {
679 int tocpy;
680 int bufoff;
681 dmu_buf_t *db = dbp[i];
682
683 ASSERT(size > 0);
684
685 bufoff = uio->uio_loffset - db->db_offset;
686 tocpy = (int)MIN(db->db_size - bufoff, size);
687
688 err = uiomove((char *)db->db_data + bufoff, tocpy,
689 UIO_READ, uio);
690 if (err)
691 break;
692
693 size -= tocpy;
694 }
695 dmu_buf_rele_array(dbp, numbufs, FTAG);
696
697 return (err);
698 }
699
700 int
701 dmu_write_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size,
702 dmu_tx_t *tx)
703 {
704 dmu_buf_t **dbp;
705 int numbufs, i;
706 int err = 0;
707
708 if (size == 0)
709 return (0);
710
711 err = dmu_buf_hold_array(os, object, uio->uio_loffset, size,
712 FALSE, FTAG, &numbufs, &dbp);
713 if (err)
714 return (err);
715
716 for (i = 0; i < numbufs; i++) {
717 int tocpy;
718 int bufoff;
719 dmu_buf_t *db = dbp[i];
720
721 ASSERT(size > 0);
722
723 bufoff = uio->uio_loffset - db->db_offset;
724 tocpy = (int)MIN(db->db_size - bufoff, size);
725
726 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
727
728 if (tocpy == db->db_size)
729 dmu_buf_will_fill(db, tx);
730 else
731 dmu_buf_will_dirty(db, tx);
732
733 /*
734 * XXX uiomove could block forever (eg. nfs-backed
735 * pages). There needs to be a uiolockdown() function
736 * to lock the pages in memory, so that uiomove won't
737 * block.
738 */
739 err = uiomove((char *)db->db_data + bufoff, tocpy,
740 UIO_WRITE, uio);
741
742 if (tocpy == db->db_size)
743 dmu_buf_fill_done(db, tx);
744
745 if (err)
746 break;
747
748 size -= tocpy;
749 }
750 dmu_buf_rele_array(dbp, numbufs, FTAG);
751 return (err);
752 }
753
754 int
755 dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
756 page_t *pp, dmu_tx_t *tx)
757 {
758 dmu_buf_t **dbp;
759 int numbufs, i;
760 int err;
761
762 if (size == 0)
763 return (0);
764
765 err = dmu_buf_hold_array(os, object, offset, size,
766 FALSE, FTAG, &numbufs, &dbp);
767 if (err)
768 return (err);
769
770 for (i = 0; i < numbufs; i++) {
771 int tocpy, copied, thiscpy;
772 int bufoff;
773 dmu_buf_t *db = dbp[i];
774 caddr_t va;
775
776 ASSERT(size > 0);
777 ASSERT3U(db->db_size, >=, PAGESIZE);
778
779 bufoff = offset - db->db_offset;
780 tocpy = (int)MIN(db->db_size - bufoff, size);
781
782 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
783
784 if (tocpy == db->db_size)
785 dmu_buf_will_fill(db, tx);
786 else
787 dmu_buf_will_dirty(db, tx);
788
789 for (copied = 0; copied < tocpy; copied += PAGESIZE) {
790 ASSERT3U(pp->p_offset, ==, db->db_offset + bufoff);
791 thiscpy = MIN(PAGESIZE, tocpy - copied);
792 va = zfs_map_page(pp, S_READ);
793 bcopy(va, (char *)db->db_data + bufoff, thiscpy);
794 zfs_unmap_page(pp, va);
795 pp = pp->p_next;
796 bufoff += PAGESIZE;
797 }
798
799 if (tocpy == db->db_size)
800 dmu_buf_fill_done(db, tx);
801
802 offset += tocpy;
803 size -= tocpy;
804 }
805 dmu_buf_rele_array(dbp, numbufs, FTAG);
806 return (err);
807 }
808 #endif
809
810 /*
811 * Allocate a loaned anonymous arc buffer.
812 */
813 arc_buf_t *
814 dmu_request_arcbuf(dmu_buf_t *handle, int size)
815 {
816 dnode_t *dn = ((dmu_buf_impl_t *)handle)->db_dnode;
817
818 return (arc_loan_buf(dn->dn_objset->os_spa, size));
819 }
820
821 /*
822 * Free a loaned arc buffer.
823 */
824 void
825 dmu_return_arcbuf(arc_buf_t *buf)
826 {
827 arc_return_buf(buf, FTAG);
828 VERIFY(arc_buf_remove_ref(buf, FTAG) == 1);
829 }
830
831 /*
832 * When possible directly assign passed loaned arc buffer to a dbuf.
833 * If this is not possible copy the contents of passed arc buf via
834 * dmu_write().
835 */
836 void
837 dmu_assign_arcbuf(dmu_buf_t *handle, uint64_t offset, arc_buf_t *buf,
838 dmu_tx_t *tx)
839 {
840 dnode_t *dn = ((dmu_buf_impl_t *)handle)->db_dnode;
841 dmu_buf_impl_t *db;
842 uint32_t blksz = (uint32_t)arc_buf_size(buf);
843 uint64_t blkid;
844
845 rw_enter(&dn->dn_struct_rwlock, RW_READER);
846 blkid = dbuf_whichblock(dn, offset);
847 VERIFY((db = dbuf_hold(dn, blkid, FTAG)) != NULL);
848 rw_exit(&dn->dn_struct_rwlock);
849
850 if (offset == db->db.db_offset && blksz == db->db.db_size) {
851 dbuf_assign_arcbuf(db, buf, tx);
852 dbuf_rele(db, FTAG);
853 } else {
854 dbuf_rele(db, FTAG);
855 ASSERT(dn->dn_objset->os.os == dn->dn_objset);
856 dmu_write(&dn->dn_objset->os, dn->dn_object, offset, blksz,
857 buf->b_data, tx);
858 dmu_return_arcbuf(buf);
859 }
860 }
861
862 typedef struct {
863 dbuf_dirty_record_t *dr;
864 dmu_sync_cb_t *done;
865 void *arg;
866 } dmu_sync_arg_t;
867
868 /* ARGSUSED */
869 static void
870 dmu_sync_ready(zio_t *zio, arc_buf_t *buf, void *varg)
871 {
872 blkptr_t *bp = zio->io_bp;
873
874 if (!BP_IS_HOLE(bp)) {
875 dmu_sync_arg_t *in = varg;
876 dbuf_dirty_record_t *dr = in->dr;
877 dmu_buf_impl_t *db = dr->dr_dbuf;
878 ASSERT(BP_GET_TYPE(bp) == db->db_dnode->dn_type);
879 ASSERT(BP_GET_LEVEL(bp) == 0);
880 bp->blk_fill = 1;
881 }
882 }
883
884 /* ARGSUSED */
885 static void
886 dmu_sync_done(zio_t *zio, arc_buf_t *buf, void *varg)
887 {
888 dmu_sync_arg_t *in = varg;
889 dbuf_dirty_record_t *dr = in->dr;
890 dmu_buf_impl_t *db = dr->dr_dbuf;
891 dmu_sync_cb_t *done = in->done;
892
893 mutex_enter(&db->db_mtx);
894 ASSERT(dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC);
895 dr->dt.dl.dr_overridden_by = *zio->io_bp; /* structure assignment */
896 dr->dt.dl.dr_override_state = DR_OVERRIDDEN;
897 cv_broadcast(&db->db_changed);
898 mutex_exit(&db->db_mtx);
899
900 if (done)
901 done(&(db->db), in->arg);
902
903 kmem_free(in, sizeof (dmu_sync_arg_t));
904 }
905
906 /*
907 * Intent log support: sync the block associated with db to disk.
908 * N.B. and XXX: the caller is responsible for making sure that the
909 * data isn't changing while dmu_sync() is writing it.
910 *
911 * Return values:
912 *
913 * EEXIST: this txg has already been synced, so there's nothing to to.
914 * The caller should not log the write.
915 *
916 * ENOENT: the block was dbuf_free_range()'d, so there's nothing to do.
917 * The caller should not log the write.
918 *
919 * EALREADY: this block is already in the process of being synced.
920 * The caller should track its progress (somehow).
921 *
922 * EINPROGRESS: the IO has been initiated.
923 * The caller should log this blkptr in the callback.
924 *
925 * 0: completed. Sets *bp to the blkptr just written.
926 * The caller should log this blkptr immediately.
927 */
928 int
929 dmu_sync(zio_t *pio, dmu_buf_t *db_fake,
930 blkptr_t *bp, uint64_t txg, dmu_sync_cb_t *done, void *arg)
931 {
932 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
933 objset_impl_t *os = db->db_objset;
934 dsl_pool_t *dp = os->os_dsl_dataset->ds_dir->dd_pool;
935 tx_state_t *tx = &dp->dp_tx;
936 dbuf_dirty_record_t *dr;
937 dmu_sync_arg_t *in;
938 zbookmark_t zb;
939 writeprops_t wp = { 0 };
940 zio_t *zio;
941 int err;
942
943 ASSERT(BP_IS_HOLE(bp));
944 ASSERT(txg != 0);
945
946 dprintf("dmu_sync txg=%llu, s,o,q %llu %llu %llu\n",
947 txg, tx->tx_synced_txg, tx->tx_open_txg, tx->tx_quiesced_txg);
948
949 /*
950 * XXX - would be nice if we could do this without suspending...
951 */
952 txg_suspend(dp);
953
954 /*
955 * If this txg already synced, there's nothing to do.
956 */
957 if (txg <= tx->tx_synced_txg) {
958 txg_resume(dp);
959 /*
960 * If we're running ziltest, we need the blkptr regardless.
961 */
962 if (txg > spa_freeze_txg(dp->dp_spa)) {
963 /* if db_blkptr == NULL, this was an empty write */
964 if (db->db_blkptr)
965 *bp = *db->db_blkptr; /* structure assignment */
966 return (0);
967 }
968 return (EEXIST);
969 }
970
971 mutex_enter(&db->db_mtx);
972
973 if (txg == tx->tx_syncing_txg) {
974 while (db->db_data_pending) {
975 /*
976 * IO is in-progress. Wait for it to finish.
977 * XXX - would be nice to be able to somehow "attach"
978 * this zio to the parent zio passed in.
979 */
980 cv_wait(&db->db_changed, &db->db_mtx);
981 if (!db->db_data_pending &&
982 db->db_blkptr && BP_IS_HOLE(db->db_blkptr)) {
983 /*
984 * IO was compressed away
985 */
986 *bp = *db->db_blkptr; /* structure assignment */
987 mutex_exit(&db->db_mtx);
988 txg_resume(dp);
989 return (0);
990 }
991 ASSERT(db->db_data_pending ||
992 (db->db_blkptr && db->db_blkptr->blk_birth == txg));
993 }
994
995 if (db->db_blkptr && db->db_blkptr->blk_birth == txg) {
996 /*
997 * IO is already completed.
998 */
999 *bp = *db->db_blkptr; /* structure assignment */
1000 mutex_exit(&db->db_mtx);
1001 txg_resume(dp);
1002 return (0);
1003 }
1004 }
1005
1006 dr = db->db_last_dirty;
1007 while (dr && dr->dr_txg > txg)
1008 dr = dr->dr_next;
1009 if (dr == NULL || dr->dr_txg < txg) {
1010 /*
1011 * This dbuf isn't dirty, must have been free_range'd.
1012 * There's no need to log writes to freed blocks, so we're done.
1013 */
1014 mutex_exit(&db->db_mtx);
1015 txg_resume(dp);
1016 return (ENOENT);
1017 }
1018
1019 ASSERT(dr->dr_txg == txg);
1020 if (dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC) {
1021 /*
1022 * We have already issued a sync write for this buffer.
1023 */
1024 mutex_exit(&db->db_mtx);
1025 txg_resume(dp);
1026 return (EALREADY);
1027 } else if (dr->dt.dl.dr_override_state == DR_OVERRIDDEN) {
1028 /*
1029 * This buffer has already been synced. It could not
1030 * have been dirtied since, or we would have cleared the state.
1031 */
1032 *bp = dr->dt.dl.dr_overridden_by; /* structure assignment */
1033 mutex_exit(&db->db_mtx);
1034 txg_resume(dp);
1035 return (0);
1036 }
1037
1038 dr->dt.dl.dr_override_state = DR_IN_DMU_SYNC;
1039 in = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP);
1040 in->dr = dr;
1041 in->done = done;
1042 in->arg = arg;
1043 mutex_exit(&db->db_mtx);
1044 txg_resume(dp);
1045
1046 zb.zb_objset = os->os_dsl_dataset->ds_object;
1047 zb.zb_object = db->db.db_object;
1048 zb.zb_level = db->db_level;
1049 zb.zb_blkid = db->db_blkid;
1050
1051 wp.wp_type = db->db_dnode->dn_type;
1052 wp.wp_level = db->db_level;
1053 wp.wp_copies = os->os_copies;
1054 wp.wp_dnchecksum = db->db_dnode->dn_checksum;
1055 wp.wp_oschecksum = os->os_checksum;
1056 wp.wp_dncompress = db->db_dnode->dn_compress;
1057 wp.wp_oscompress = os->os_compress;
1058
1059 ASSERT(BP_IS_HOLE(bp));
1060
1061 zio = arc_write(pio, os->os_spa, &wp, DBUF_IS_L2CACHEABLE(db),
1062 txg, bp, dr->dt.dl.dr_data, dmu_sync_ready, dmu_sync_done, in,
1063 ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_MUSTSUCCEED, &zb);
1064 if (pio) {
1065 zio_nowait(zio);
1066 err = EINPROGRESS;
1067 } else {
1068 err = zio_wait(zio);
1069 ASSERT(err == 0);
1070 }
1071 return (err);
1072 }
1073
1074 int
1075 dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, int ibs,
1076 dmu_tx_t *tx)
1077 {
1078 dnode_t *dn;
1079 int err;
1080
1081 err = dnode_hold(os->os, object, FTAG, &dn);
1082 if (err)
1083 return (err);
1084 err = dnode_set_blksz(dn, size, ibs, tx);
1085 dnode_rele(dn, FTAG);
1086 return (err);
1087 }
1088
1089 void
1090 dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum,
1091 dmu_tx_t *tx)
1092 {
1093 dnode_t *dn;
1094
1095 /* XXX assumes dnode_hold will not get an i/o error */
1096 (void) dnode_hold(os->os, object, FTAG, &dn);
1097 ASSERT(checksum < ZIO_CHECKSUM_FUNCTIONS);
1098 dn->dn_checksum = checksum;
1099 dnode_setdirty(dn, tx);
1100 dnode_rele(dn, FTAG);
1101 }
1102
1103 void
1104 dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress,
1105 dmu_tx_t *tx)
1106 {
1107 dnode_t *dn;
1108
1109 /* XXX assumes dnode_hold will not get an i/o error */
1110 (void) dnode_hold(os->os, object, FTAG, &dn);
1111 ASSERT(compress < ZIO_COMPRESS_FUNCTIONS);
1112 dn->dn_compress = compress;
1113 dnode_setdirty(dn, tx);
1114 dnode_rele(dn, FTAG);
1115 }
1116
1117 int
1118 dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, uint64_t *off)
1119 {
1120 dnode_t *dn;
1121 int i, err;
1122
1123 err = dnode_hold(os->os, object, FTAG, &dn);
1124 if (err)
1125 return (err);
1126 /*
1127 * Sync any current changes before
1128 * we go trundling through the block pointers.
1129 */
1130 for (i = 0; i < TXG_SIZE; i++) {
1131 if (list_link_active(&dn->dn_dirty_link[i]))
1132 break;
1133 }
1134 if (i != TXG_SIZE) {
1135 dnode_rele(dn, FTAG);
1136 txg_wait_synced(dmu_objset_pool(os), 0);
1137 err = dnode_hold(os->os, object, FTAG, &dn);
1138 if (err)
1139 return (err);
1140 }
1141
1142 err = dnode_next_offset(dn, (hole ? DNODE_FIND_HOLE : 0), off, 1, 1, 0);
1143 dnode_rele(dn, FTAG);
1144
1145 return (err);
1146 }
1147
1148 void
1149 dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi)
1150 {
1151 rw_enter(&dn->dn_struct_rwlock, RW_READER);
1152 mutex_enter(&dn->dn_mtx);
1153
1154 doi->doi_data_block_size = dn->dn_datablksz;
1155 doi->doi_metadata_block_size = dn->dn_indblkshift ?
1156 1ULL << dn->dn_indblkshift : 0;
1157 doi->doi_indirection = dn->dn_nlevels;
1158 doi->doi_checksum = dn->dn_checksum;
1159 doi->doi_compress = dn->dn_compress;
1160 doi->doi_physical_blks = (DN_USED_BYTES(dn->dn_phys) +
1161 SPA_MINBLOCKSIZE/2) >> SPA_MINBLOCKSHIFT;
1162 doi->doi_max_block_offset = dn->dn_phys->dn_maxblkid;
1163 doi->doi_type = dn->dn_type;
1164 doi->doi_bonus_size = dn->dn_bonuslen;
1165 doi->doi_bonus_type = dn->dn_bonustype;
1166
1167 mutex_exit(&dn->dn_mtx);
1168 rw_exit(&dn->dn_struct_rwlock);
1169 }
1170
1171 /*
1172 * Get information on a DMU object.
1173 * If doi is NULL, just indicates whether the object exists.
1174 */
1175 int
1176 dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi)
1177 {
1178 dnode_t *dn;
1179 int err = dnode_hold(os->os, object, FTAG, &dn);
1180
1181 if (err)
1182 return (err);
1183
1184 if (doi != NULL)
1185 dmu_object_info_from_dnode(dn, doi);
1186
1187 dnode_rele(dn, FTAG);
1188 return (0);
1189 }
1190
1191 /*
1192 * As above, but faster; can be used when you have a held dbuf in hand.
1193 */
1194 void
1195 dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi)
1196 {
1197 dmu_object_info_from_dnode(((dmu_buf_impl_t *)db)->db_dnode, doi);
1198 }
1199
1200 /*
1201 * Faster still when you only care about the size.
1202 * This is specifically optimized for zfs_getattr().
1203 */
1204 void
1205 dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize, u_longlong_t *nblk512)
1206 {
1207 dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode;
1208
1209 *blksize = dn->dn_datablksz;
1210 /* add 1 for dnode space */
1211 *nblk512 = ((DN_USED_BYTES(dn->dn_phys) + SPA_MINBLOCKSIZE/2) >>
1212 SPA_MINBLOCKSHIFT) + 1;
1213 }
1214
1215 void
1216 byteswap_uint64_array(void *vbuf, size_t size)
1217 {
1218 uint64_t *buf = vbuf;
1219 size_t count = size >> 3;
1220 int i;
1221
1222 ASSERT((size & 7) == 0);
1223
1224 for (i = 0; i < count; i++)
1225 buf[i] = BSWAP_64(buf[i]);
1226 }
1227
1228 void
1229 byteswap_uint32_array(void *vbuf, size_t size)
1230 {
1231 uint32_t *buf = vbuf;
1232 size_t count = size >> 2;
1233 int i;
1234
1235 ASSERT((size & 3) == 0);
1236
1237 for (i = 0; i < count; i++)
1238 buf[i] = BSWAP_32(buf[i]);
1239 }
1240
1241 void
1242 byteswap_uint16_array(void *vbuf, size_t size)
1243 {
1244 uint16_t *buf = vbuf;
1245 size_t count = size >> 1;
1246 int i;
1247
1248 ASSERT((size & 1) == 0);
1249
1250 for (i = 0; i < count; i++)
1251 buf[i] = BSWAP_16(buf[i]);
1252 }
1253
1254 /* ARGSUSED */
1255 void
1256 byteswap_uint8_array(void *vbuf, size_t size)
1257 {
1258 }
1259
1260 void
1261 dmu_init(void)
1262 {
1263 dbuf_init();
1264 dnode_init();
1265 arc_init();
1266 l2arc_init();
1267 }
1268
1269 void
1270 dmu_fini(void)
1271 {
1272 arc_fini();
1273 dnode_fini();
1274 dbuf_fini();
1275 l2arc_fini();
1276 }
ZFS On Linux mirror for PVE