4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
24 * Copyright (c) 2013 by Delphix. All rights reserved.
28 #include <sys/dmu_impl.h>
30 #include <sys/dmu_tx.h>
31 #include <sys/dmu_objset.h>
32 #include <sys/dsl_dataset.h> /* for dsl_dataset_block_freeable() */
33 #include <sys/dsl_dir.h> /* for dsl_dir_tempreserve_*() */
34 #include <sys/dsl_pool.h>
35 #include <sys/zap_impl.h> /* for fzap_default_block_shift */
38 #include <sys/sa_impl.h>
39 #include <sys/zfs_context.h>
40 #include <sys/varargs.h>
42 typedef void (*dmu_tx_hold_func_t)(dmu_tx_t *tx, struct dnode *dn,
43 uint64_t arg1, uint64_t arg2);
47 dmu_tx_create_dd(dsl_dir_t *dd)
49 dmu_tx_t *tx = kmem_zalloc(sizeof (dmu_tx_t), KM_SLEEP);
52 tx->tx_pool = dd->dd_pool;
53 list_create(&tx->tx_holds, sizeof (dmu_tx_hold_t),
54 offsetof(dmu_tx_hold_t, txh_node));
55 list_create(&tx->tx_callbacks, sizeof (dmu_tx_callback_t),
56 offsetof(dmu_tx_callback_t, dcb_node));
58 refcount_create(&tx->tx_space_written);
59 refcount_create(&tx->tx_space_freed);
65 dmu_tx_create(objset_t *os)
67 dmu_tx_t *tx = dmu_tx_create_dd(os->os_dsl_dataset->ds_dir);
69 tx->tx_lastsnap_txg = dsl_dataset_prev_snap_txg(os->os_dsl_dataset);
74 dmu_tx_create_assigned(struct dsl_pool *dp, uint64_t txg)
76 dmu_tx_t *tx = dmu_tx_create_dd(NULL);
78 ASSERT3U(txg, <=, dp->dp_tx.tx_open_txg);
87 dmu_tx_is_syncing(dmu_tx_t *tx)
89 return (tx->tx_anyobj);
93 dmu_tx_private_ok(dmu_tx_t *tx)
95 return (tx->tx_anyobj);
98 static dmu_tx_hold_t *
99 dmu_tx_hold_object_impl(dmu_tx_t *tx, objset_t *os, uint64_t object,
100 enum dmu_tx_hold_type type, uint64_t arg1, uint64_t arg2)
106 if (object != DMU_NEW_OBJECT) {
107 err = dnode_hold(os, object, tx, &dn);
113 if (err == 0 && tx->tx_txg != 0) {
114 mutex_enter(&dn->dn_mtx);
116 * dn->dn_assigned_txg == tx->tx_txg doesn't pose a
117 * problem, but there's no way for it to happen (for
120 ASSERT(dn->dn_assigned_txg == 0);
121 dn->dn_assigned_txg = tx->tx_txg;
122 (void) refcount_add(&dn->dn_tx_holds, tx);
123 mutex_exit(&dn->dn_mtx);
127 txh = kmem_zalloc(sizeof (dmu_tx_hold_t), KM_SLEEP);
131 txh->txh_type = type;
132 txh->txh_arg1 = arg1;
133 txh->txh_arg2 = arg2;
135 list_insert_tail(&tx->tx_holds, txh);
141 dmu_tx_add_new_object(dmu_tx_t *tx, objset_t *os, uint64_t object)
144 * If we're syncing, they can manipulate any object anyhow, and
145 * the hold on the dnode_t can cause problems.
147 if (!dmu_tx_is_syncing(tx)) {
148 (void) dmu_tx_hold_object_impl(tx, os,
149 object, THT_NEWOBJECT, 0, 0);
154 dmu_tx_check_ioerr(zio_t *zio, dnode_t *dn, int level, uint64_t blkid)
159 rw_enter(&dn->dn_struct_rwlock, RW_READER);
160 db = dbuf_hold_level(dn, level, blkid, FTAG);
161 rw_exit(&dn->dn_struct_rwlock);
163 return (SET_ERROR(EIO));
164 err = dbuf_read(db, zio, DB_RF_CANFAIL | DB_RF_NOPREFETCH);
170 dmu_tx_count_twig(dmu_tx_hold_t *txh, dnode_t *dn, dmu_buf_impl_t *db,
171 int level, uint64_t blkid, boolean_t freeable, uint64_t *history)
173 objset_t *os = dn->dn_objset;
174 dsl_dataset_t *ds = os->os_dsl_dataset;
175 int epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT;
176 dmu_buf_impl_t *parent = NULL;
180 if (level >= dn->dn_nlevels || history[level] == blkid)
183 history[level] = blkid;
185 space = (level == 0) ? dn->dn_datablksz : (1ULL << dn->dn_indblkshift);
187 if (db == NULL || db == dn->dn_dbuf) {
191 ASSERT(DB_DNODE(db) == dn);
192 ASSERT(db->db_level == level);
193 ASSERT(db->db.db_size == space);
194 ASSERT(db->db_blkid == blkid);
196 parent = db->db_parent;
199 freeable = (bp && (freeable ||
200 dsl_dataset_block_freeable(ds, bp, bp->blk_birth)));
203 txh->txh_space_tooverwrite += space;
205 txh->txh_space_towrite += space;
207 txh->txh_space_tounref += bp_get_dsize(os->os_spa, bp);
209 dmu_tx_count_twig(txh, dn, parent, level + 1,
210 blkid >> epbs, freeable, history);
215 dmu_tx_count_write(dmu_tx_hold_t *txh, uint64_t off, uint64_t len)
217 dnode_t *dn = txh->txh_dnode;
218 uint64_t start, end, i;
219 int min_bs, max_bs, min_ibs, max_ibs, epbs, bits;
225 min_bs = SPA_MINBLOCKSHIFT;
226 max_bs = SPA_MAXBLOCKSHIFT;
227 min_ibs = DN_MIN_INDBLKSHIFT;
228 max_ibs = DN_MAX_INDBLKSHIFT;
231 uint64_t history[DN_MAX_LEVELS];
232 int nlvls = dn->dn_nlevels;
236 * For i/o error checking, read the first and last level-0
237 * blocks (if they are not aligned), and all the level-1 blocks.
239 if (dn->dn_maxblkid == 0) {
240 delta = dn->dn_datablksz;
241 start = (off < dn->dn_datablksz) ? 0 : 1;
242 end = (off+len <= dn->dn_datablksz) ? 0 : 1;
243 if (start == 0 && (off > 0 || len < dn->dn_datablksz)) {
244 err = dmu_tx_check_ioerr(NULL, dn, 0, 0);
250 zio_t *zio = zio_root(dn->dn_objset->os_spa,
251 NULL, NULL, ZIO_FLAG_CANFAIL);
253 /* first level-0 block */
254 start = off >> dn->dn_datablkshift;
255 if (P2PHASE(off, dn->dn_datablksz) ||
256 len < dn->dn_datablksz) {
257 err = dmu_tx_check_ioerr(zio, dn, 0, start);
262 /* last level-0 block */
263 end = (off+len-1) >> dn->dn_datablkshift;
264 if (end != start && end <= dn->dn_maxblkid &&
265 P2PHASE(off+len, dn->dn_datablksz)) {
266 err = dmu_tx_check_ioerr(zio, dn, 0, end);
273 int shft = dn->dn_indblkshift - SPA_BLKPTRSHIFT;
274 for (i = (start>>shft)+1; i < end>>shft; i++) {
275 err = dmu_tx_check_ioerr(zio, dn, 1, i);
284 delta = P2NPHASE(off, dn->dn_datablksz);
287 min_ibs = max_ibs = dn->dn_indblkshift;
288 if (dn->dn_maxblkid > 0) {
290 * The blocksize can't change,
291 * so we can make a more precise estimate.
293 ASSERT(dn->dn_datablkshift != 0);
294 min_bs = max_bs = dn->dn_datablkshift;
298 * If this write is not off the end of the file
299 * we need to account for overwrites/unref.
301 if (start <= dn->dn_maxblkid) {
302 for (int l = 0; l < DN_MAX_LEVELS; l++)
305 while (start <= dn->dn_maxblkid) {
308 rw_enter(&dn->dn_struct_rwlock, RW_READER);
309 err = dbuf_hold_impl(dn, 0, start, FALSE, FTAG, &db);
310 rw_exit(&dn->dn_struct_rwlock);
313 txh->txh_tx->tx_err = err;
317 dmu_tx_count_twig(txh, dn, db, 0, start, B_FALSE,
322 * Account for new indirects appearing
323 * before this IO gets assigned into a txg.
326 epbs = min_ibs - SPA_BLKPTRSHIFT;
327 for (bits -= epbs * (nlvls - 1);
328 bits >= 0; bits -= epbs)
329 txh->txh_fudge += 1ULL << max_ibs;
335 delta = dn->dn_datablksz;
340 * 'end' is the last thing we will access, not one past.
341 * This way we won't overflow when accessing the last byte.
343 start = P2ALIGN(off, 1ULL << max_bs);
344 end = P2ROUNDUP(off + len, 1ULL << max_bs) - 1;
345 txh->txh_space_towrite += end - start + 1;
350 epbs = min_ibs - SPA_BLKPTRSHIFT;
353 * The object contains at most 2^(64 - min_bs) blocks,
354 * and each indirect level maps 2^epbs.
356 for (bits = 64 - min_bs; bits >= 0; bits -= epbs) {
359 ASSERT3U(end, >=, start);
360 txh->txh_space_towrite += (end - start + 1) << max_ibs;
363 * We also need a new blkid=0 indirect block
364 * to reference any existing file data.
366 txh->txh_space_towrite += 1ULL << max_ibs;
371 if (txh->txh_space_towrite + txh->txh_space_tooverwrite >
373 err = SET_ERROR(EFBIG);
376 txh->txh_tx->tx_err = err;
380 dmu_tx_count_dnode(dmu_tx_hold_t *txh)
382 dnode_t *dn = txh->txh_dnode;
383 dnode_t *mdn = DMU_META_DNODE(txh->txh_tx->tx_objset);
384 uint64_t space = mdn->dn_datablksz +
385 ((mdn->dn_nlevels-1) << mdn->dn_indblkshift);
387 if (dn && dn->dn_dbuf->db_blkptr &&
388 dsl_dataset_block_freeable(dn->dn_objset->os_dsl_dataset,
389 dn->dn_dbuf->db_blkptr, dn->dn_dbuf->db_blkptr->blk_birth)) {
390 txh->txh_space_tooverwrite += space;
391 txh->txh_space_tounref += space;
393 txh->txh_space_towrite += space;
394 if (dn && dn->dn_dbuf->db_blkptr)
395 txh->txh_space_tounref += space;
400 dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len)
404 ASSERT(tx->tx_txg == 0);
405 ASSERT(len < DMU_MAX_ACCESS);
406 ASSERT(len == 0 || UINT64_MAX - off >= len - 1);
408 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset,
409 object, THT_WRITE, off, len);
413 dmu_tx_count_write(txh, off, len);
414 dmu_tx_count_dnode(txh);
418 dmu_tx_count_free(dmu_tx_hold_t *txh, uint64_t off, uint64_t len)
420 uint64_t blkid, nblks, lastblk;
421 uint64_t space = 0, unref = 0, skipped = 0;
422 dnode_t *dn = txh->txh_dnode;
423 dsl_dataset_t *ds = dn->dn_objset->os_dsl_dataset;
424 spa_t *spa = txh->txh_tx->tx_pool->dp_spa;
426 uint64_t l0span = 0, nl1blks = 0;
428 if (dn->dn_nlevels == 0)
432 * The struct_rwlock protects us against dn_nlevels
433 * changing, in case (against all odds) we manage to dirty &
434 * sync out the changes after we check for being dirty.
435 * Also, dbuf_hold_impl() wants us to have the struct_rwlock.
437 rw_enter(&dn->dn_struct_rwlock, RW_READER);
438 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT;
439 if (dn->dn_maxblkid == 0) {
440 if (off == 0 && len >= dn->dn_datablksz) {
444 rw_exit(&dn->dn_struct_rwlock);
448 blkid = off >> dn->dn_datablkshift;
449 nblks = (len + dn->dn_datablksz - 1) >> dn->dn_datablkshift;
451 if (blkid > dn->dn_maxblkid) {
452 rw_exit(&dn->dn_struct_rwlock);
455 if (blkid + nblks > dn->dn_maxblkid)
456 nblks = dn->dn_maxblkid - blkid + 1;
459 l0span = nblks; /* save for later use to calc level > 1 overhead */
460 if (dn->dn_nlevels == 1) {
462 for (i = 0; i < nblks; i++) {
463 blkptr_t *bp = dn->dn_phys->dn_blkptr;
464 ASSERT3U(blkid + i, <, dn->dn_nblkptr);
466 if (dsl_dataset_block_freeable(ds, bp, bp->blk_birth)) {
467 dprintf_bp(bp, "can free old%s", "");
468 space += bp_get_dsize(spa, bp);
470 unref += BP_GET_ASIZE(bp);
476 lastblk = blkid + nblks - 1;
478 dmu_buf_impl_t *dbuf;
479 uint64_t ibyte, new_blkid;
481 int err, i, blkoff, tochk;
484 ibyte = blkid << dn->dn_datablkshift;
485 err = dnode_next_offset(dn,
486 DNODE_FIND_HAVELOCK, &ibyte, 2, 1, 0);
487 new_blkid = ibyte >> dn->dn_datablkshift;
489 skipped += (lastblk >> epbs) - (blkid >> epbs) + 1;
493 txh->txh_tx->tx_err = err;
496 if (new_blkid > lastblk) {
497 skipped += (lastblk >> epbs) - (blkid >> epbs) + 1;
501 if (new_blkid > blkid) {
502 ASSERT((new_blkid >> epbs) > (blkid >> epbs));
503 skipped += (new_blkid >> epbs) - (blkid >> epbs) - 1;
504 nblks -= new_blkid - blkid;
507 blkoff = P2PHASE(blkid, epb);
508 tochk = MIN(epb - blkoff, nblks);
510 err = dbuf_hold_impl(dn, 1, blkid >> epbs, FALSE, FTAG, &dbuf);
512 txh->txh_tx->tx_err = err;
516 txh->txh_memory_tohold += dbuf->db.db_size;
519 * We don't check memory_tohold against DMU_MAX_ACCESS because
520 * memory_tohold is an over-estimation (especially the >L1
521 * indirect blocks), so it could fail. Callers should have
522 * already verified that they will not be holding too much
526 err = dbuf_read(dbuf, NULL, DB_RF_HAVESTRUCT | DB_RF_CANFAIL);
528 txh->txh_tx->tx_err = err;
529 dbuf_rele(dbuf, FTAG);
533 bp = dbuf->db.db_data;
536 for (i = 0; i < tochk; i++) {
537 if (dsl_dataset_block_freeable(ds, &bp[i],
539 dprintf_bp(&bp[i], "can free old%s", "");
540 space += bp_get_dsize(spa, &bp[i]);
542 unref += BP_GET_ASIZE(bp);
544 dbuf_rele(dbuf, FTAG);
550 rw_exit(&dn->dn_struct_rwlock);
553 * Add in memory requirements of higher-level indirects.
554 * This assumes a worst-possible scenario for dn_nlevels and a
555 * worst-possible distribution of l1-blocks over the region to free.
558 uint64_t blkcnt = 1 + ((l0span >> epbs) >> epbs);
561 * Here we don't use DN_MAX_LEVEL, but calculate it with the
562 * given datablkshift and indblkshift. This makes the
563 * difference between 19 and 8 on large files.
565 int maxlevel = 2 + (DN_MAX_OFFSET_SHIFT - dn->dn_datablkshift) /
566 (dn->dn_indblkshift - SPA_BLKPTRSHIFT);
568 while (level++ < maxlevel) {
569 txh->txh_memory_tohold += MAX(MIN(blkcnt, nl1blks), 1)
570 << dn->dn_indblkshift;
571 blkcnt = 1 + (blkcnt >> epbs);
575 /* account for new level 1 indirect blocks that might show up */
577 txh->txh_fudge += skipped << dn->dn_indblkshift;
578 skipped = MIN(skipped, DMU_MAX_DELETEBLKCNT >> epbs);
579 txh->txh_memory_tohold += skipped << dn->dn_indblkshift;
581 txh->txh_space_tofree += space;
582 txh->txh_space_tounref += unref;
586 dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off, uint64_t len)
593 ASSERT(tx->tx_txg == 0);
595 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset,
596 object, THT_FREE, off, len);
601 if (off >= (dn->dn_maxblkid+1) * dn->dn_datablksz)
603 if (len == DMU_OBJECT_END)
604 len = (dn->dn_maxblkid+1) * dn->dn_datablksz - off;
606 dmu_tx_count_dnode(txh);
609 * For i/o error checking, we read the first and last level-0
610 * blocks if they are not aligned, and all the level-1 blocks.
612 * Note: dbuf_free_range() assumes that we have not instantiated
613 * any level-0 dbufs that will be completely freed. Therefore we must
614 * exercise care to not read or count the first and last blocks
615 * if they are blocksize-aligned.
617 if (dn->dn_datablkshift == 0) {
618 if (off != 0 || len < dn->dn_datablksz)
619 dmu_tx_count_write(txh, 0, dn->dn_datablksz);
621 /* first block will be modified if it is not aligned */
622 if (!IS_P2ALIGNED(off, 1 << dn->dn_datablkshift))
623 dmu_tx_count_write(txh, off, 1);
624 /* last block will be modified if it is not aligned */
625 if (!IS_P2ALIGNED(off + len, 1 << dn->dn_datablkshift))
626 dmu_tx_count_write(txh, off+len, 1);
630 * Check level-1 blocks.
632 if (dn->dn_nlevels > 1) {
633 int shift = dn->dn_datablkshift + dn->dn_indblkshift -
635 uint64_t start = off >> shift;
636 uint64_t end = (off + len) >> shift;
638 ASSERT(dn->dn_datablkshift != 0);
639 ASSERT(dn->dn_indblkshift != 0);
641 zio = zio_root(tx->tx_pool->dp_spa,
642 NULL, NULL, ZIO_FLAG_CANFAIL);
643 for (uint64_t i = start; i <= end; i++) {
644 uint64_t ibyte = i << shift;
645 err = dnode_next_offset(dn, 0, &ibyte, 2, 1, 0);
654 err = dmu_tx_check_ioerr(zio, dn, 1, i);
667 dmu_tx_count_free(txh, off, len);
671 dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, const char *name)
678 ASSERT(tx->tx_txg == 0);
680 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset,
681 object, THT_ZAP, add, (uintptr_t)name);
686 dmu_tx_count_dnode(txh);
690 * We will be able to fit a new object's entries into one leaf
691 * block. So there will be at most 2 blocks total,
692 * including the header block.
694 dmu_tx_count_write(txh, 0, 2 << fzap_default_block_shift);
698 ASSERT3P(DMU_OT_BYTESWAP(dn->dn_type), ==, DMU_BSWAP_ZAP);
700 if (dn->dn_maxblkid == 0 && !add) {
704 * If there is only one block (i.e. this is a micro-zap)
705 * and we are not adding anything, the accounting is simple.
707 err = dmu_tx_check_ioerr(NULL, dn, 0, 0);
714 * Use max block size here, since we don't know how much
715 * the size will change between now and the dbuf dirty call.
717 bp = &dn->dn_phys->dn_blkptr[0];
718 if (dsl_dataset_block_freeable(dn->dn_objset->os_dsl_dataset,
720 txh->txh_space_tooverwrite += SPA_MAXBLOCKSIZE;
722 txh->txh_space_towrite += SPA_MAXBLOCKSIZE;
724 txh->txh_space_tounref += SPA_MAXBLOCKSIZE;
728 if (dn->dn_maxblkid > 0 && name) {
730 * access the name in this fat-zap so that we'll check
731 * for i/o errors to the leaf blocks, etc.
733 err = zap_lookup(dn->dn_objset, dn->dn_object, name,
741 err = zap_count_write(dn->dn_objset, dn->dn_object, name, add,
742 &txh->txh_space_towrite, &txh->txh_space_tooverwrite);
745 * If the modified blocks are scattered to the four winds,
746 * we'll have to modify an indirect twig for each.
748 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT;
749 for (nblocks = dn->dn_maxblkid >> epbs; nblocks != 0; nblocks >>= epbs)
750 if (dn->dn_objset->os_dsl_dataset->ds_phys->ds_prev_snap_obj)
751 txh->txh_space_towrite += 3 << dn->dn_indblkshift;
753 txh->txh_space_tooverwrite += 3 << dn->dn_indblkshift;
757 dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object)
761 ASSERT(tx->tx_txg == 0);
763 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset,
764 object, THT_BONUS, 0, 0);
766 dmu_tx_count_dnode(txh);
770 dmu_tx_hold_space(dmu_tx_t *tx, uint64_t space)
773 ASSERT(tx->tx_txg == 0);
775 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset,
776 DMU_NEW_OBJECT, THT_SPACE, space, 0);
778 txh->txh_space_towrite += space;
782 dmu_tx_holds(dmu_tx_t *tx, uint64_t object)
788 * By asserting that the tx is assigned, we're counting the
789 * number of dn_tx_holds, which is the same as the number of
790 * dn_holds. Otherwise, we'd be counting dn_holds, but
791 * dn_tx_holds could be 0.
793 ASSERT(tx->tx_txg != 0);
795 /* if (tx->tx_anyobj == TRUE) */
798 for (txh = list_head(&tx->tx_holds); txh;
799 txh = list_next(&tx->tx_holds, txh)) {
800 if (txh->txh_dnode && txh->txh_dnode->dn_object == object)
809 dmu_tx_dirty_buf(dmu_tx_t *tx, dmu_buf_impl_t *db)
812 int match_object = FALSE, match_offset = FALSE;
817 ASSERT(tx->tx_txg != 0);
818 ASSERT(tx->tx_objset == NULL || dn->dn_objset == tx->tx_objset);
819 ASSERT3U(dn->dn_object, ==, db->db.db_object);
826 /* XXX No checking on the meta dnode for now */
827 if (db->db.db_object == DMU_META_DNODE_OBJECT) {
832 for (txh = list_head(&tx->tx_holds); txh;
833 txh = list_next(&tx->tx_holds, txh)) {
834 ASSERT(dn == NULL || dn->dn_assigned_txg == tx->tx_txg);
835 if (txh->txh_dnode == dn && txh->txh_type != THT_NEWOBJECT)
837 if (txh->txh_dnode == NULL || txh->txh_dnode == dn) {
838 int datablkshift = dn->dn_datablkshift ?
839 dn->dn_datablkshift : SPA_MAXBLOCKSHIFT;
840 int epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT;
841 int shift = datablkshift + epbs * db->db_level;
842 uint64_t beginblk = shift >= 64 ? 0 :
843 (txh->txh_arg1 >> shift);
844 uint64_t endblk = shift >= 64 ? 0 :
845 ((txh->txh_arg1 + txh->txh_arg2 - 1) >> shift);
846 uint64_t blkid = db->db_blkid;
848 /* XXX txh_arg2 better not be zero... */
850 dprintf("found txh type %x beginblk=%llx endblk=%llx\n",
851 txh->txh_type, beginblk, endblk);
853 switch (txh->txh_type) {
855 if (blkid >= beginblk && blkid <= endblk)
858 * We will let this hold work for the bonus
859 * or spill buffer so that we don't need to
860 * hold it when creating a new object.
862 if (blkid == DMU_BONUS_BLKID ||
863 blkid == DMU_SPILL_BLKID)
866 * They might have to increase nlevels,
867 * thus dirtying the new TLIBs. Or the
868 * might have to change the block size,
869 * thus dirying the new lvl=0 blk=0.
876 * We will dirty all the level 1 blocks in
877 * the free range and perhaps the first and
878 * last level 0 block.
880 if (blkid >= beginblk && (blkid <= endblk ||
881 txh->txh_arg2 == DMU_OBJECT_END))
885 if (blkid == DMU_SPILL_BLKID)
889 if (blkid == DMU_BONUS_BLKID)
899 ASSERT(!"bad txh_type");
902 if (match_object && match_offset) {
908 panic("dirtying dbuf obj=%llx lvl=%u blkid=%llx but not tx_held\n",
909 (u_longlong_t)db->db.db_object, db->db_level,
910 (u_longlong_t)db->db_blkid);
915 dmu_tx_try_assign(dmu_tx_t *tx, txg_how_t txg_how)
918 spa_t *spa = tx->tx_pool->dp_spa;
919 uint64_t memory, asize, fsize, usize;
920 uint64_t towrite, tofree, tooverwrite, tounref, tohold, fudge;
927 if (spa_suspended(spa)) {
929 * If the user has indicated a blocking failure mode
930 * then return ERESTART which will block in dmu_tx_wait().
931 * Otherwise, return EIO so that an error can get
932 * propagated back to the VOP calls.
934 * Note that we always honor the txg_how flag regardless
935 * of the failuremode setting.
937 if (spa_get_failmode(spa) == ZIO_FAILURE_MODE_CONTINUE &&
939 return (SET_ERROR(EIO));
941 return (SET_ERROR(ERESTART));
944 tx->tx_txg = txg_hold_open(tx->tx_pool, &tx->tx_txgh);
945 tx->tx_needassign_txh = NULL;
948 * NB: No error returns are allowed after txg_hold_open, but
949 * before processing the dnode holds, due to the
950 * dmu_tx_unassign() logic.
953 towrite = tofree = tooverwrite = tounref = tohold = fudge = 0;
954 for (txh = list_head(&tx->tx_holds); txh;
955 txh = list_next(&tx->tx_holds, txh)) {
956 dnode_t *dn = txh->txh_dnode;
958 mutex_enter(&dn->dn_mtx);
959 if (dn->dn_assigned_txg == tx->tx_txg - 1) {
960 mutex_exit(&dn->dn_mtx);
961 tx->tx_needassign_txh = txh;
962 return (SET_ERROR(ERESTART));
964 if (dn->dn_assigned_txg == 0)
965 dn->dn_assigned_txg = tx->tx_txg;
966 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg);
967 (void) refcount_add(&dn->dn_tx_holds, tx);
968 mutex_exit(&dn->dn_mtx);
970 towrite += txh->txh_space_towrite;
971 tofree += txh->txh_space_tofree;
972 tooverwrite += txh->txh_space_tooverwrite;
973 tounref += txh->txh_space_tounref;
974 tohold += txh->txh_memory_tohold;
975 fudge += txh->txh_fudge;
979 * If a snapshot has been taken since we made our estimates,
980 * assume that we won't be able to free or overwrite anything.
983 dsl_dataset_prev_snap_txg(tx->tx_objset->os_dsl_dataset) >
984 tx->tx_lastsnap_txg) {
985 towrite += tooverwrite;
986 tooverwrite = tofree = 0;
989 /* needed allocation: worst-case estimate of write space */
990 asize = spa_get_asize(tx->tx_pool->dp_spa, towrite + tooverwrite);
991 /* freed space estimate: worst-case overwrite + free estimate */
992 fsize = spa_get_asize(tx->tx_pool->dp_spa, tooverwrite) + tofree;
993 /* convert unrefd space to worst-case estimate */
994 usize = spa_get_asize(tx->tx_pool->dp_spa, tounref);
995 /* calculate memory footprint estimate */
996 memory = towrite + tooverwrite + tohold;
1000 * Add in 'tohold' to account for our dirty holds on this memory
1001 * XXX - the "fudge" factor is to account for skipped blocks that
1002 * we missed because dnode_next_offset() misses in-core-only blocks.
1004 tx->tx_space_towrite = asize +
1005 spa_get_asize(tx->tx_pool->dp_spa, tohold + fudge);
1006 tx->tx_space_tofree = tofree;
1007 tx->tx_space_tooverwrite = tooverwrite;
1008 tx->tx_space_tounref = tounref;
1011 if (tx->tx_dir && asize != 0) {
1012 int err = dsl_dir_tempreserve_space(tx->tx_dir, memory,
1013 asize, fsize, usize, &tx->tx_tempreserve_cookie, tx);
1022 dmu_tx_unassign(dmu_tx_t *tx)
1026 if (tx->tx_txg == 0)
1029 txg_rele_to_quiesce(&tx->tx_txgh);
1032 * Walk the transaction's hold list, removing the hold on the
1033 * associated dnode, and notifying waiters if the refcount drops to 0.
1035 for (txh = list_head(&tx->tx_holds); txh != tx->tx_needassign_txh;
1036 txh = list_next(&tx->tx_holds, txh)) {
1037 dnode_t *dn = txh->txh_dnode;
1041 mutex_enter(&dn->dn_mtx);
1042 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg);
1044 if (refcount_remove(&dn->dn_tx_holds, tx) == 0) {
1045 dn->dn_assigned_txg = 0;
1046 cv_broadcast(&dn->dn_notxholds);
1048 mutex_exit(&dn->dn_mtx);
1051 txg_rele_to_sync(&tx->tx_txgh);
1053 tx->tx_lasttried_txg = tx->tx_txg;
1058 * Assign tx to a transaction group. txg_how can be one of:
1060 * (1) TXG_WAIT. If the current open txg is full, waits until there's
1061 * a new one. This should be used when you're not holding locks.
1062 * It will only fail if we're truly out of space (or over quota).
1064 * (2) TXG_NOWAIT. If we can't assign into the current open txg without
1065 * blocking, returns immediately with ERESTART. This should be used
1066 * whenever you're holding locks. On an ERESTART error, the caller
1067 * should drop locks, do a dmu_tx_wait(tx), and try again.
1070 dmu_tx_assign(dmu_tx_t *tx, txg_how_t txg_how)
1074 ASSERT(tx->tx_txg == 0);
1075 ASSERT(txg_how == TXG_WAIT || txg_how == TXG_NOWAIT);
1076 ASSERT(!dsl_pool_sync_context(tx->tx_pool));
1078 /* If we might wait, we must not hold the config lock. */
1079 ASSERT(txg_how != TXG_WAIT || !dsl_pool_config_held(tx->tx_pool));
1081 while ((err = dmu_tx_try_assign(tx, txg_how)) != 0) {
1082 dmu_tx_unassign(tx);
1084 if (err != ERESTART || txg_how != TXG_WAIT)
1090 txg_rele_to_quiesce(&tx->tx_txgh);
1096 dmu_tx_wait(dmu_tx_t *tx)
1098 spa_t *spa = tx->tx_pool->dp_spa;
1100 ASSERT(tx->tx_txg == 0);
1101 ASSERT(!dsl_pool_config_held(tx->tx_pool));
1104 * It's possible that the pool has become active after this thread
1105 * has tried to obtain a tx. If that's the case then his
1106 * tx_lasttried_txg would not have been assigned.
1108 if (spa_suspended(spa) || tx->tx_lasttried_txg == 0) {
1109 txg_wait_synced(tx->tx_pool, spa_last_synced_txg(spa) + 1);
1110 } else if (tx->tx_needassign_txh) {
1111 dnode_t *dn = tx->tx_needassign_txh->txh_dnode;
1113 mutex_enter(&dn->dn_mtx);
1114 while (dn->dn_assigned_txg == tx->tx_lasttried_txg - 1)
1115 cv_wait(&dn->dn_notxholds, &dn->dn_mtx);
1116 mutex_exit(&dn->dn_mtx);
1117 tx->tx_needassign_txh = NULL;
1119 txg_wait_open(tx->tx_pool, tx->tx_lasttried_txg + 1);
1124 dmu_tx_willuse_space(dmu_tx_t *tx, int64_t delta)
1127 if (tx->tx_dir == NULL || delta == 0)
1131 ASSERT3U(refcount_count(&tx->tx_space_written) + delta, <=,
1132 tx->tx_space_towrite);
1133 (void) refcount_add_many(&tx->tx_space_written, delta, NULL);
1135 (void) refcount_add_many(&tx->tx_space_freed, -delta, NULL);
1141 dmu_tx_commit(dmu_tx_t *tx)
1145 ASSERT(tx->tx_txg != 0);
1148 * Go through the transaction's hold list and remove holds on
1149 * associated dnodes, notifying waiters if no holds remain.
1151 while (txh = list_head(&tx->tx_holds)) {
1152 dnode_t *dn = txh->txh_dnode;
1154 list_remove(&tx->tx_holds, txh);
1155 kmem_free(txh, sizeof (dmu_tx_hold_t));
1158 mutex_enter(&dn->dn_mtx);
1159 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg);
1161 if (refcount_remove(&dn->dn_tx_holds, tx) == 0) {
1162 dn->dn_assigned_txg = 0;
1163 cv_broadcast(&dn->dn_notxholds);
1165 mutex_exit(&dn->dn_mtx);
1169 if (tx->tx_tempreserve_cookie)
1170 dsl_dir_tempreserve_clear(tx->tx_tempreserve_cookie, tx);
1172 if (!list_is_empty(&tx->tx_callbacks))
1173 txg_register_callbacks(&tx->tx_txgh, &tx->tx_callbacks);
1175 if (tx->tx_anyobj == FALSE)
1176 txg_rele_to_sync(&tx->tx_txgh);
1178 list_destroy(&tx->tx_callbacks);
1179 list_destroy(&tx->tx_holds);
1181 dprintf("towrite=%llu written=%llu tofree=%llu freed=%llu\n",
1182 tx->tx_space_towrite, refcount_count(&tx->tx_space_written),
1183 tx->tx_space_tofree, refcount_count(&tx->tx_space_freed));
1184 refcount_destroy_many(&tx->tx_space_written,
1185 refcount_count(&tx->tx_space_written));
1186 refcount_destroy_many(&tx->tx_space_freed,
1187 refcount_count(&tx->tx_space_freed));
1189 kmem_free(tx, sizeof (dmu_tx_t));
1193 dmu_tx_abort(dmu_tx_t *tx)
1197 ASSERT(tx->tx_txg == 0);
1199 while (txh = list_head(&tx->tx_holds)) {
1200 dnode_t *dn = txh->txh_dnode;
1202 list_remove(&tx->tx_holds, txh);
1203 kmem_free(txh, sizeof (dmu_tx_hold_t));
1209 * Call any registered callbacks with an error code.
1211 if (!list_is_empty(&tx->tx_callbacks))
1212 dmu_tx_do_callbacks(&tx->tx_callbacks, ECANCELED);
1214 list_destroy(&tx->tx_callbacks);
1215 list_destroy(&tx->tx_holds);
1217 refcount_destroy_many(&tx->tx_space_written,
1218 refcount_count(&tx->tx_space_written));
1219 refcount_destroy_many(&tx->tx_space_freed,
1220 refcount_count(&tx->tx_space_freed));
1222 kmem_free(tx, sizeof (dmu_tx_t));
1226 dmu_tx_get_txg(dmu_tx_t *tx)
1228 ASSERT(tx->tx_txg != 0);
1229 return (tx->tx_txg);
1233 dmu_tx_pool(dmu_tx_t *tx)
1235 ASSERT(tx->tx_pool != NULL);
1236 return (tx->tx_pool);
1241 dmu_tx_callback_register(dmu_tx_t *tx, dmu_tx_callback_func_t *func, void *data)
1243 dmu_tx_callback_t *dcb;
1245 dcb = kmem_alloc(sizeof (dmu_tx_callback_t), KM_SLEEP);
1247 dcb->dcb_func = func;
1248 dcb->dcb_data = data;
1250 list_insert_tail(&tx->tx_callbacks, dcb);
1254 * Call all the commit callbacks on a list, with a given error code.
1257 dmu_tx_do_callbacks(list_t *cb_list, int error)
1259 dmu_tx_callback_t *dcb;
1261 while (dcb = list_head(cb_list)) {
1262 list_remove(cb_list, dcb);
1263 dcb->dcb_func(dcb->dcb_data, error);
1264 kmem_free(dcb, sizeof (dmu_tx_callback_t));
1269 * Interface to hold a bunch of attributes.
1270 * used for creating new files.
1271 * attrsize is the total size of all attributes
1272 * to be added during object creation
1274 * For updating/adding a single attribute dmu_tx_hold_sa() should be used.
1278 * hold necessary attribute name for attribute registration.
1279 * should be a very rare case where this is needed. If it does
1280 * happen it would only happen on the first write to the file system.
1283 dmu_tx_sa_registration_hold(sa_os_t *sa, dmu_tx_t *tx)
1287 if (!sa->sa_need_attr_registration)
1290 for (i = 0; i != sa->sa_num_attrs; i++) {
1291 if (!sa->sa_attr_table[i].sa_registered) {
1292 if (sa->sa_reg_attr_obj)
1293 dmu_tx_hold_zap(tx, sa->sa_reg_attr_obj,
1294 B_TRUE, sa->sa_attr_table[i].sa_name);
1296 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT,
1297 B_TRUE, sa->sa_attr_table[i].sa_name);
1304 dmu_tx_hold_spill(dmu_tx_t *tx, uint64_t object)
1309 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, object,
1312 dn = txh->txh_dnode;
1317 /* If blkptr doesn't exist then add space to towrite */
1318 if (!(dn->dn_phys->dn_flags & DNODE_FLAG_SPILL_BLKPTR)) {
1319 txh->txh_space_towrite += SPA_MAXBLOCKSIZE;
1323 bp = &dn->dn_phys->dn_spill;
1324 if (dsl_dataset_block_freeable(dn->dn_objset->os_dsl_dataset,
1326 txh->txh_space_tooverwrite += SPA_MAXBLOCKSIZE;
1328 txh->txh_space_towrite += SPA_MAXBLOCKSIZE;
1329 if (!BP_IS_HOLE(bp))
1330 txh->txh_space_tounref += SPA_MAXBLOCKSIZE;
1335 dmu_tx_hold_sa_create(dmu_tx_t *tx, int attrsize)
1337 sa_os_t *sa = tx->tx_objset->os_sa;
1339 dmu_tx_hold_bonus(tx, DMU_NEW_OBJECT);
1341 if (tx->tx_objset->os_sa->sa_master_obj == 0)
1344 if (tx->tx_objset->os_sa->sa_layout_attr_obj)
1345 dmu_tx_hold_zap(tx, sa->sa_layout_attr_obj, B_TRUE, NULL);
1347 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_LAYOUTS);
1348 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_REGISTRY);
1349 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL);
1350 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL);
1353 dmu_tx_sa_registration_hold(sa, tx);
1355 if (attrsize <= DN_MAX_BONUSLEN && !sa->sa_force_spill)
1358 (void) dmu_tx_hold_object_impl(tx, tx->tx_objset, DMU_NEW_OBJECT,
1365 * dmu_tx_hold_sa(dmu_tx_t *tx, sa_handle_t *, attribute, add, size)
1367 * variable_size is the total size of all variable sized attributes
1368 * passed to this function. It is not the total size of all
1369 * variable size attributes that *may* exist on this object.
1372 dmu_tx_hold_sa(dmu_tx_t *tx, sa_handle_t *hdl, boolean_t may_grow)
1375 sa_os_t *sa = tx->tx_objset->os_sa;
1377 ASSERT(hdl != NULL);
1379 object = sa_handle_object(hdl);
1381 dmu_tx_hold_bonus(tx, object);
1383 if (tx->tx_objset->os_sa->sa_master_obj == 0)
1386 if (tx->tx_objset->os_sa->sa_reg_attr_obj == 0 ||
1387 tx->tx_objset->os_sa->sa_layout_attr_obj == 0) {
1388 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_LAYOUTS);
1389 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_REGISTRY);
1390 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL);
1391 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL);
1394 dmu_tx_sa_registration_hold(sa, tx);
1396 if (may_grow && tx->tx_objset->os_sa->sa_layout_attr_obj)
1397 dmu_tx_hold_zap(tx, sa->sa_layout_attr_obj, B_TRUE, NULL);
1399 if (sa->sa_force_spill || may_grow || hdl->sa_spill) {
1400 ASSERT(tx->tx_txg == 0);
1401 dmu_tx_hold_spill(tx, object);
1403 dmu_buf_impl_t *db = (dmu_buf_impl_t *)hdl->sa_bonus;
1408 if (dn->dn_have_spill) {
1409 ASSERT(tx->tx_txg == 0);
1410 dmu_tx_hold_spill(tx, object);