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);
45 dmu_tx_stats_t dmu_tx_stats = {
46 { "dmu_tx_assigned", KSTAT_DATA_UINT64 },
47 { "dmu_tx_delay", KSTAT_DATA_UINT64 },
48 { "dmu_tx_error", KSTAT_DATA_UINT64 },
49 { "dmu_tx_suspended", KSTAT_DATA_UINT64 },
50 { "dmu_tx_group", KSTAT_DATA_UINT64 },
51 { "dmu_tx_how", KSTAT_DATA_UINT64 },
52 { "dmu_tx_memory_reserve", KSTAT_DATA_UINT64 },
53 { "dmu_tx_memory_reclaim", KSTAT_DATA_UINT64 },
54 { "dmu_tx_memory_inflight", KSTAT_DATA_UINT64 },
55 { "dmu_tx_dirty_throttle", KSTAT_DATA_UINT64 },
56 { "dmu_tx_write_limit", KSTAT_DATA_UINT64 },
57 { "dmu_tx_quota", KSTAT_DATA_UINT64 },
60 static kstat_t *dmu_tx_ksp;
63 dmu_tx_create_dd(dsl_dir_t *dd)
65 dmu_tx_t *tx = kmem_zalloc(sizeof (dmu_tx_t), KM_PUSHPAGE);
68 tx->tx_pool = dd->dd_pool;
69 list_create(&tx->tx_holds, sizeof (dmu_tx_hold_t),
70 offsetof(dmu_tx_hold_t, txh_node));
71 list_create(&tx->tx_callbacks, sizeof (dmu_tx_callback_t),
72 offsetof(dmu_tx_callback_t, dcb_node));
74 refcount_create(&tx->tx_space_written);
75 refcount_create(&tx->tx_space_freed);
81 dmu_tx_create(objset_t *os)
83 dmu_tx_t *tx = dmu_tx_create_dd(os->os_dsl_dataset->ds_dir);
85 tx->tx_lastsnap_txg = dsl_dataset_prev_snap_txg(os->os_dsl_dataset);
90 dmu_tx_create_assigned(struct dsl_pool *dp, uint64_t txg)
92 dmu_tx_t *tx = dmu_tx_create_dd(NULL);
94 ASSERT3U(txg, <=, dp->dp_tx.tx_open_txg);
103 dmu_tx_is_syncing(dmu_tx_t *tx)
105 return (tx->tx_anyobj);
109 dmu_tx_private_ok(dmu_tx_t *tx)
111 return (tx->tx_anyobj);
114 static dmu_tx_hold_t *
115 dmu_tx_hold_object_impl(dmu_tx_t *tx, objset_t *os, uint64_t object,
116 enum dmu_tx_hold_type type, uint64_t arg1, uint64_t arg2)
122 if (object != DMU_NEW_OBJECT) {
123 err = dnode_hold(os, object, tx, &dn);
129 if (err == 0 && tx->tx_txg != 0) {
130 mutex_enter(&dn->dn_mtx);
132 * dn->dn_assigned_txg == tx->tx_txg doesn't pose a
133 * problem, but there's no way for it to happen (for
136 ASSERT(dn->dn_assigned_txg == 0);
137 dn->dn_assigned_txg = tx->tx_txg;
138 (void) refcount_add(&dn->dn_tx_holds, tx);
139 mutex_exit(&dn->dn_mtx);
143 txh = kmem_zalloc(sizeof (dmu_tx_hold_t), KM_PUSHPAGE);
147 txh->txh_type = type;
148 txh->txh_arg1 = arg1;
149 txh->txh_arg2 = arg2;
151 list_insert_tail(&tx->tx_holds, txh);
157 dmu_tx_add_new_object(dmu_tx_t *tx, objset_t *os, uint64_t object)
160 * If we're syncing, they can manipulate any object anyhow, and
161 * the hold on the dnode_t can cause problems.
163 if (!dmu_tx_is_syncing(tx)) {
164 (void) dmu_tx_hold_object_impl(tx, os,
165 object, THT_NEWOBJECT, 0, 0);
170 dmu_tx_check_ioerr(zio_t *zio, dnode_t *dn, int level, uint64_t blkid)
175 rw_enter(&dn->dn_struct_rwlock, RW_READER);
176 db = dbuf_hold_level(dn, level, blkid, FTAG);
177 rw_exit(&dn->dn_struct_rwlock);
180 err = dbuf_read(db, zio, DB_RF_CANFAIL | DB_RF_NOPREFETCH);
186 dmu_tx_count_twig(dmu_tx_hold_t *txh, dnode_t *dn, dmu_buf_impl_t *db,
187 int level, uint64_t blkid, boolean_t freeable, uint64_t *history)
189 objset_t *os = dn->dn_objset;
190 dsl_dataset_t *ds = os->os_dsl_dataset;
191 int epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT;
192 dmu_buf_impl_t *parent = NULL;
196 if (level >= dn->dn_nlevels || history[level] == blkid)
199 history[level] = blkid;
201 space = (level == 0) ? dn->dn_datablksz : (1ULL << dn->dn_indblkshift);
203 if (db == NULL || db == dn->dn_dbuf) {
207 ASSERT(DB_DNODE(db) == dn);
208 ASSERT(db->db_level == level);
209 ASSERT(db->db.db_size == space);
210 ASSERT(db->db_blkid == blkid);
212 parent = db->db_parent;
215 freeable = (bp && (freeable ||
216 dsl_dataset_block_freeable(ds, bp, bp->blk_birth)));
219 txh->txh_space_tooverwrite += space;
221 txh->txh_space_towrite += space;
223 txh->txh_space_tounref += bp_get_dsize(os->os_spa, bp);
225 dmu_tx_count_twig(txh, dn, parent, level + 1,
226 blkid >> epbs, freeable, history);
231 dmu_tx_count_write(dmu_tx_hold_t *txh, uint64_t off, uint64_t len)
233 dnode_t *dn = txh->txh_dnode;
234 uint64_t start, end, i;
235 int min_bs, max_bs, min_ibs, max_ibs, epbs, bits;
242 min_bs = SPA_MINBLOCKSHIFT;
243 max_bs = SPA_MAXBLOCKSHIFT;
244 min_ibs = DN_MIN_INDBLKSHIFT;
245 max_ibs = DN_MAX_INDBLKSHIFT;
248 uint64_t history[DN_MAX_LEVELS];
249 int nlvls = dn->dn_nlevels;
253 * For i/o error checking, read the first and last level-0
254 * blocks (if they are not aligned), and all the level-1 blocks.
256 if (dn->dn_maxblkid == 0) {
257 delta = dn->dn_datablksz;
258 start = (off < dn->dn_datablksz) ? 0 : 1;
259 end = (off+len <= dn->dn_datablksz) ? 0 : 1;
260 if (start == 0 && (off > 0 || len < dn->dn_datablksz)) {
261 err = dmu_tx_check_ioerr(NULL, dn, 0, 0);
267 zio_t *zio = zio_root(dn->dn_objset->os_spa,
268 NULL, NULL, ZIO_FLAG_CANFAIL);
270 /* first level-0 block */
271 start = off >> dn->dn_datablkshift;
272 if (P2PHASE(off, dn->dn_datablksz) ||
273 len < dn->dn_datablksz) {
274 err = dmu_tx_check_ioerr(zio, dn, 0, start);
279 /* last level-0 block */
280 end = (off+len-1) >> dn->dn_datablkshift;
281 if (end != start && end <= dn->dn_maxblkid &&
282 P2PHASE(off+len, dn->dn_datablksz)) {
283 err = dmu_tx_check_ioerr(zio, dn, 0, end);
290 int shft = dn->dn_indblkshift - SPA_BLKPTRSHIFT;
291 for (i = (start>>shft)+1; i < end>>shft; i++) {
292 err = dmu_tx_check_ioerr(zio, dn, 1, i);
301 delta = P2NPHASE(off, dn->dn_datablksz);
304 min_ibs = max_ibs = dn->dn_indblkshift;
305 if (dn->dn_maxblkid > 0) {
307 * The blocksize can't change,
308 * so we can make a more precise estimate.
310 ASSERT(dn->dn_datablkshift != 0);
311 min_bs = max_bs = dn->dn_datablkshift;
315 * If this write is not off the end of the file
316 * we need to account for overwrites/unref.
318 if (start <= dn->dn_maxblkid) {
319 for (l = 0; l < DN_MAX_LEVELS; l++)
322 while (start <= dn->dn_maxblkid) {
325 rw_enter(&dn->dn_struct_rwlock, RW_READER);
326 err = dbuf_hold_impl(dn, 0, start, FALSE, FTAG, &db);
327 rw_exit(&dn->dn_struct_rwlock);
330 txh->txh_tx->tx_err = err;
334 dmu_tx_count_twig(txh, dn, db, 0, start, B_FALSE,
339 * Account for new indirects appearing
340 * before this IO gets assigned into a txg.
343 epbs = min_ibs - SPA_BLKPTRSHIFT;
344 for (bits -= epbs * (nlvls - 1);
345 bits >= 0; bits -= epbs)
346 txh->txh_fudge += 1ULL << max_ibs;
352 delta = dn->dn_datablksz;
357 * 'end' is the last thing we will access, not one past.
358 * This way we won't overflow when accessing the last byte.
360 start = P2ALIGN(off, 1ULL << max_bs);
361 end = P2ROUNDUP(off + len, 1ULL << max_bs) - 1;
362 txh->txh_space_towrite += end - start + 1;
367 epbs = min_ibs - SPA_BLKPTRSHIFT;
370 * The object contains at most 2^(64 - min_bs) blocks,
371 * and each indirect level maps 2^epbs.
373 for (bits = 64 - min_bs; bits >= 0; bits -= epbs) {
376 ASSERT3U(end, >=, start);
377 txh->txh_space_towrite += (end - start + 1) << max_ibs;
380 * We also need a new blkid=0 indirect block
381 * to reference any existing file data.
383 txh->txh_space_towrite += 1ULL << max_ibs;
388 if (txh->txh_space_towrite + txh->txh_space_tooverwrite >
393 txh->txh_tx->tx_err = err;
397 dmu_tx_count_dnode(dmu_tx_hold_t *txh)
399 dnode_t *dn = txh->txh_dnode;
400 dnode_t *mdn = DMU_META_DNODE(txh->txh_tx->tx_objset);
401 uint64_t space = mdn->dn_datablksz +
402 ((mdn->dn_nlevels-1) << mdn->dn_indblkshift);
404 if (dn && dn->dn_dbuf->db_blkptr &&
405 dsl_dataset_block_freeable(dn->dn_objset->os_dsl_dataset,
406 dn->dn_dbuf->db_blkptr, dn->dn_dbuf->db_blkptr->blk_birth)) {
407 txh->txh_space_tooverwrite += space;
408 txh->txh_space_tounref += space;
410 txh->txh_space_towrite += space;
411 if (dn && dn->dn_dbuf->db_blkptr)
412 txh->txh_space_tounref += space;
417 dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len)
421 ASSERT(tx->tx_txg == 0);
422 ASSERT(len < DMU_MAX_ACCESS);
423 ASSERT(len == 0 || UINT64_MAX - off >= len - 1);
425 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset,
426 object, THT_WRITE, off, len);
430 dmu_tx_count_write(txh, off, len);
431 dmu_tx_count_dnode(txh);
435 dmu_tx_count_free(dmu_tx_hold_t *txh, uint64_t off, uint64_t len)
437 uint64_t blkid, nblks, lastblk;
438 uint64_t space = 0, unref = 0, skipped = 0;
439 dnode_t *dn = txh->txh_dnode;
440 dsl_dataset_t *ds = dn->dn_objset->os_dsl_dataset;
441 spa_t *spa = txh->txh_tx->tx_pool->dp_spa;
443 uint64_t l0span = 0, nl1blks = 0;
445 if (dn->dn_nlevels == 0)
449 * The struct_rwlock protects us against dn_nlevels
450 * changing, in case (against all odds) we manage to dirty &
451 * sync out the changes after we check for being dirty.
452 * Also, dbuf_hold_impl() wants us to have the struct_rwlock.
454 rw_enter(&dn->dn_struct_rwlock, RW_READER);
455 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT;
456 if (dn->dn_maxblkid == 0) {
457 if (off == 0 && len >= dn->dn_datablksz) {
461 rw_exit(&dn->dn_struct_rwlock);
465 blkid = off >> dn->dn_datablkshift;
466 nblks = (len + dn->dn_datablksz - 1) >> dn->dn_datablkshift;
468 if (blkid >= dn->dn_maxblkid) {
469 rw_exit(&dn->dn_struct_rwlock);
472 if (blkid + nblks > dn->dn_maxblkid)
473 nblks = dn->dn_maxblkid - blkid;
476 l0span = nblks; /* save for later use to calc level > 1 overhead */
477 if (dn->dn_nlevels == 1) {
479 for (i = 0; i < nblks; i++) {
480 blkptr_t *bp = dn->dn_phys->dn_blkptr;
481 ASSERT3U(blkid + i, <, dn->dn_nblkptr);
483 if (dsl_dataset_block_freeable(ds, bp, bp->blk_birth)) {
484 dprintf_bp(bp, "can free old%s", "");
485 space += bp_get_dsize(spa, bp);
487 unref += BP_GET_ASIZE(bp);
493 lastblk = blkid + nblks - 1;
495 dmu_buf_impl_t *dbuf;
496 uint64_t ibyte, new_blkid;
498 int err, i, blkoff, tochk;
501 ibyte = blkid << dn->dn_datablkshift;
502 err = dnode_next_offset(dn,
503 DNODE_FIND_HAVELOCK, &ibyte, 2, 1, 0);
504 new_blkid = ibyte >> dn->dn_datablkshift;
506 skipped += (lastblk >> epbs) - (blkid >> epbs) + 1;
510 txh->txh_tx->tx_err = err;
513 if (new_blkid > lastblk) {
514 skipped += (lastblk >> epbs) - (blkid >> epbs) + 1;
518 if (new_blkid > blkid) {
519 ASSERT((new_blkid >> epbs) > (blkid >> epbs));
520 skipped += (new_blkid >> epbs) - (blkid >> epbs) - 1;
521 nblks -= new_blkid - blkid;
524 blkoff = P2PHASE(blkid, epb);
525 tochk = MIN(epb - blkoff, nblks);
527 err = dbuf_hold_impl(dn, 1, blkid >> epbs, FALSE, FTAG, &dbuf);
529 txh->txh_tx->tx_err = err;
533 txh->txh_memory_tohold += dbuf->db.db_size;
536 * We don't check memory_tohold against DMU_MAX_ACCESS because
537 * memory_tohold is an over-estimation (especially the >L1
538 * indirect blocks), so it could fail. Callers should have
539 * already verified that they will not be holding too much
543 err = dbuf_read(dbuf, NULL, DB_RF_HAVESTRUCT | DB_RF_CANFAIL);
545 txh->txh_tx->tx_err = err;
546 dbuf_rele(dbuf, FTAG);
550 bp = dbuf->db.db_data;
553 for (i = 0; i < tochk; i++) {
554 if (dsl_dataset_block_freeable(ds, &bp[i],
556 dprintf_bp(&bp[i], "can free old%s", "");
557 space += bp_get_dsize(spa, &bp[i]);
559 unref += BP_GET_ASIZE(bp);
561 dbuf_rele(dbuf, FTAG);
567 rw_exit(&dn->dn_struct_rwlock);
570 * Add in memory requirements of higher-level indirects.
571 * This assumes a worst-possible scenario for dn_nlevels and a
572 * worst-possible distribution of l1-blocks over the region to free.
575 uint64_t blkcnt = 1 + ((l0span >> epbs) >> epbs);
578 * Here we don't use DN_MAX_LEVEL, but calculate it with the
579 * given datablkshift and indblkshift. This makes the
580 * difference between 19 and 8 on large files.
582 int maxlevel = 2 + (DN_MAX_OFFSET_SHIFT - dn->dn_datablkshift) /
583 (dn->dn_indblkshift - SPA_BLKPTRSHIFT);
585 while (level++ < maxlevel) {
586 txh->txh_memory_tohold += MAX(MIN(blkcnt, nl1blks), 1)
587 << dn->dn_indblkshift;
588 blkcnt = 1 + (blkcnt >> epbs);
592 /* account for new level 1 indirect blocks that might show up */
594 txh->txh_fudge += skipped << dn->dn_indblkshift;
595 skipped = MIN(skipped, DMU_MAX_DELETEBLKCNT >> epbs);
596 txh->txh_memory_tohold += skipped << dn->dn_indblkshift;
598 txh->txh_space_tofree += space;
599 txh->txh_space_tounref += unref;
603 dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off, uint64_t len)
607 uint64_t start, end, i;
611 ASSERT(tx->tx_txg == 0);
613 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset,
614 object, THT_FREE, off, len);
621 dmu_tx_count_write(txh, off, 1);
623 if (len != DMU_OBJECT_END)
624 dmu_tx_count_write(txh, off+len, 1);
626 dmu_tx_count_dnode(txh);
628 if (off >= (dn->dn_maxblkid+1) * dn->dn_datablksz)
630 if (len == DMU_OBJECT_END)
631 len = (dn->dn_maxblkid+1) * dn->dn_datablksz - off;
634 * For i/o error checking, read the first and last level-0
635 * blocks, and all the level-1 blocks. The above count_write's
636 * have already taken care of the level-0 blocks.
638 if (dn->dn_nlevels > 1) {
639 shift = dn->dn_datablkshift + dn->dn_indblkshift -
641 start = off >> shift;
642 end = dn->dn_datablkshift ? ((off+len) >> shift) : 0;
644 zio = zio_root(tx->tx_pool->dp_spa,
645 NULL, NULL, ZIO_FLAG_CANFAIL);
646 for (i = start; i <= end; i++) {
647 uint64_t ibyte = i << shift;
648 err = dnode_next_offset(dn, 0, &ibyte, 2, 1, 0);
657 err = dmu_tx_check_ioerr(zio, dn, 1, i);
670 dmu_tx_count_free(txh, off, len);
674 dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, const char *name)
681 ASSERT(tx->tx_txg == 0);
683 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset,
684 object, THT_ZAP, add, (uintptr_t)name);
689 dmu_tx_count_dnode(txh);
693 * We will be able to fit a new object's entries into one leaf
694 * block. So there will be at most 2 blocks total,
695 * including the header block.
697 dmu_tx_count_write(txh, 0, 2 << fzap_default_block_shift);
701 ASSERT3U(DMU_OT_BYTESWAP(dn->dn_type), ==, DMU_BSWAP_ZAP);
703 if (dn->dn_maxblkid == 0 && !add) {
707 * If there is only one block (i.e. this is a micro-zap)
708 * and we are not adding anything, the accounting is simple.
710 err = dmu_tx_check_ioerr(NULL, dn, 0, 0);
717 * Use max block size here, since we don't know how much
718 * the size will change between now and the dbuf dirty call.
720 bp = &dn->dn_phys->dn_blkptr[0];
721 if (dsl_dataset_block_freeable(dn->dn_objset->os_dsl_dataset,
723 txh->txh_space_tooverwrite += SPA_MAXBLOCKSIZE;
725 txh->txh_space_towrite += SPA_MAXBLOCKSIZE;
727 txh->txh_space_tounref += SPA_MAXBLOCKSIZE;
731 if (dn->dn_maxblkid > 0 && name) {
733 * access the name in this fat-zap so that we'll check
734 * for i/o errors to the leaf blocks, etc.
736 err = zap_lookup(dn->dn_objset, dn->dn_object, name,
744 err = zap_count_write(dn->dn_objset, dn->dn_object, name, add,
745 &txh->txh_space_towrite, &txh->txh_space_tooverwrite);
748 * If the modified blocks are scattered to the four winds,
749 * we'll have to modify an indirect twig for each.
751 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT;
752 for (nblocks = dn->dn_maxblkid >> epbs; nblocks != 0; nblocks >>= epbs)
753 if (dn->dn_objset->os_dsl_dataset->ds_phys->ds_prev_snap_obj)
754 txh->txh_space_towrite += 3 << dn->dn_indblkshift;
756 txh->txh_space_tooverwrite += 3 << dn->dn_indblkshift;
760 dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object)
764 ASSERT(tx->tx_txg == 0);
766 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset,
767 object, THT_BONUS, 0, 0);
769 dmu_tx_count_dnode(txh);
773 dmu_tx_hold_space(dmu_tx_t *tx, uint64_t space)
777 ASSERT(tx->tx_txg == 0);
779 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset,
780 DMU_NEW_OBJECT, THT_SPACE, space, 0);
782 txh->txh_space_towrite += space;
786 dmu_tx_holds(dmu_tx_t *tx, uint64_t object)
792 * By asserting that the tx is assigned, we're counting the
793 * number of dn_tx_holds, which is the same as the number of
794 * dn_holds. Otherwise, we'd be counting dn_holds, but
795 * dn_tx_holds could be 0.
797 ASSERT(tx->tx_txg != 0);
799 /* if (tx->tx_anyobj == TRUE) */
802 for (txh = list_head(&tx->tx_holds); txh;
803 txh = list_next(&tx->tx_holds, txh)) {
804 if (txh->txh_dnode && txh->txh_dnode->dn_object == object)
813 dmu_tx_dirty_buf(dmu_tx_t *tx, dmu_buf_impl_t *db)
816 int match_object = FALSE, match_offset = FALSE;
822 ASSERT(tx->tx_txg != 0);
823 ASSERT(tx->tx_objset == NULL || dn->dn_objset == tx->tx_objset);
824 ASSERT3U(dn->dn_object, ==, db->db.db_object);
831 /* XXX No checking on the meta dnode for now */
832 if (db->db.db_object == DMU_META_DNODE_OBJECT) {
837 for (txh = list_head(&tx->tx_holds); txh;
838 txh = list_next(&tx->tx_holds, txh)) {
839 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg);
840 if (txh->txh_dnode == dn && txh->txh_type != THT_NEWOBJECT)
842 if (txh->txh_dnode == NULL || txh->txh_dnode == dn) {
843 int datablkshift = dn->dn_datablkshift ?
844 dn->dn_datablkshift : SPA_MAXBLOCKSHIFT;
845 int epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT;
846 int shift = datablkshift + epbs * db->db_level;
847 uint64_t beginblk = shift >= 64 ? 0 :
848 (txh->txh_arg1 >> shift);
849 uint64_t endblk = shift >= 64 ? 0 :
850 ((txh->txh_arg1 + txh->txh_arg2 - 1) >> shift);
851 uint64_t blkid = db->db_blkid;
853 /* XXX txh_arg2 better not be zero... */
855 dprintf("found txh type %x beginblk=%llx endblk=%llx\n",
856 txh->txh_type, beginblk, endblk);
858 switch (txh->txh_type) {
860 if (blkid >= beginblk && blkid <= endblk)
863 * We will let this hold work for the bonus
864 * or spill buffer so that we don't need to
865 * hold it when creating a new object.
867 if (blkid == DMU_BONUS_BLKID ||
868 blkid == DMU_SPILL_BLKID)
871 * They might have to increase nlevels,
872 * thus dirtying the new TLIBs. Or the
873 * might have to change the block size,
874 * thus dirying the new lvl=0 blk=0.
881 * We will dirty all the level 1 blocks in
882 * the free range and perhaps the first and
883 * last level 0 block.
885 if (blkid >= beginblk && (blkid <= endblk ||
886 txh->txh_arg2 == DMU_OBJECT_END))
890 if (blkid == DMU_SPILL_BLKID)
894 if (blkid == DMU_BONUS_BLKID)
904 ASSERT(!"bad txh_type");
907 if (match_object && match_offset) {
913 panic("dirtying dbuf obj=%llx lvl=%u blkid=%llx but not tx_held\n",
914 (u_longlong_t)db->db.db_object, db->db_level,
915 (u_longlong_t)db->db_blkid);
920 dmu_tx_try_assign(dmu_tx_t *tx, uint64_t txg_how)
923 spa_t *spa = tx->tx_pool->dp_spa;
924 uint64_t memory, asize, fsize, usize;
925 uint64_t towrite, tofree, tooverwrite, tounref, tohold, fudge;
930 DMU_TX_STAT_BUMP(dmu_tx_error);
934 if (spa_suspended(spa)) {
935 DMU_TX_STAT_BUMP(dmu_tx_suspended);
938 * If the user has indicated a blocking failure mode
939 * then return ERESTART which will block in dmu_tx_wait().
940 * Otherwise, return EIO so that an error can get
941 * propagated back to the VOP calls.
943 * Note that we always honor the txg_how flag regardless
944 * of the failuremode setting.
946 if (spa_get_failmode(spa) == ZIO_FAILURE_MODE_CONTINUE &&
953 tx->tx_txg = txg_hold_open(tx->tx_pool, &tx->tx_txgh);
954 tx->tx_needassign_txh = NULL;
957 * NB: No error returns are allowed after txg_hold_open, but
958 * before processing the dnode holds, due to the
959 * dmu_tx_unassign() logic.
962 towrite = tofree = tooverwrite = tounref = tohold = fudge = 0;
963 for (txh = list_head(&tx->tx_holds); txh;
964 txh = list_next(&tx->tx_holds, txh)) {
965 dnode_t *dn = txh->txh_dnode;
967 mutex_enter(&dn->dn_mtx);
968 if (dn->dn_assigned_txg == tx->tx_txg - 1) {
969 mutex_exit(&dn->dn_mtx);
970 tx->tx_needassign_txh = txh;
971 DMU_TX_STAT_BUMP(dmu_tx_group);
974 if (dn->dn_assigned_txg == 0)
975 dn->dn_assigned_txg = tx->tx_txg;
976 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg);
977 (void) refcount_add(&dn->dn_tx_holds, tx);
978 mutex_exit(&dn->dn_mtx);
980 towrite += txh->txh_space_towrite;
981 tofree += txh->txh_space_tofree;
982 tooverwrite += txh->txh_space_tooverwrite;
983 tounref += txh->txh_space_tounref;
984 tohold += txh->txh_memory_tohold;
985 fudge += txh->txh_fudge;
989 * NB: This check must be after we've held the dnodes, so that
990 * the dmu_tx_unassign() logic will work properly
992 if (txg_how >= TXG_INITIAL && txg_how != tx->tx_txg) {
993 DMU_TX_STAT_BUMP(dmu_tx_how);
998 * If a snapshot has been taken since we made our estimates,
999 * assume that we won't be able to free or overwrite anything.
1001 if (tx->tx_objset &&
1002 dsl_dataset_prev_snap_txg(tx->tx_objset->os_dsl_dataset) >
1003 tx->tx_lastsnap_txg) {
1004 towrite += tooverwrite;
1005 tooverwrite = tofree = 0;
1008 /* needed allocation: worst-case estimate of write space */
1009 asize = spa_get_asize(tx->tx_pool->dp_spa, towrite + tooverwrite);
1010 /* freed space estimate: worst-case overwrite + free estimate */
1011 fsize = spa_get_asize(tx->tx_pool->dp_spa, tooverwrite) + tofree;
1012 /* convert unrefd space to worst-case estimate */
1013 usize = spa_get_asize(tx->tx_pool->dp_spa, tounref);
1014 /* calculate memory footprint estimate */
1015 memory = towrite + tooverwrite + tohold;
1019 * Add in 'tohold' to account for our dirty holds on this memory
1020 * XXX - the "fudge" factor is to account for skipped blocks that
1021 * we missed because dnode_next_offset() misses in-core-only blocks.
1023 tx->tx_space_towrite = asize +
1024 spa_get_asize(tx->tx_pool->dp_spa, tohold + fudge);
1025 tx->tx_space_tofree = tofree;
1026 tx->tx_space_tooverwrite = tooverwrite;
1027 tx->tx_space_tounref = tounref;
1030 if (tx->tx_dir && asize != 0) {
1031 int err = dsl_dir_tempreserve_space(tx->tx_dir, memory,
1032 asize, fsize, usize, &tx->tx_tempreserve_cookie, tx);
1037 DMU_TX_STAT_BUMP(dmu_tx_assigned);
1043 dmu_tx_unassign(dmu_tx_t *tx)
1047 if (tx->tx_txg == 0)
1050 txg_rele_to_quiesce(&tx->tx_txgh);
1052 for (txh = list_head(&tx->tx_holds); txh != tx->tx_needassign_txh;
1053 txh = list_next(&tx->tx_holds, txh)) {
1054 dnode_t *dn = txh->txh_dnode;
1058 mutex_enter(&dn->dn_mtx);
1059 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg);
1061 if (refcount_remove(&dn->dn_tx_holds, tx) == 0) {
1062 dn->dn_assigned_txg = 0;
1063 cv_broadcast(&dn->dn_notxholds);
1065 mutex_exit(&dn->dn_mtx);
1068 txg_rele_to_sync(&tx->tx_txgh);
1070 tx->tx_lasttried_txg = tx->tx_txg;
1075 * Assign tx to a transaction group. txg_how can be one of:
1077 * (1) TXG_WAIT. If the current open txg is full, waits until there's
1078 * a new one. This should be used when you're not holding locks.
1079 * If will only fail if we're truly out of space (or over quota).
1081 * (2) TXG_NOWAIT. If we can't assign into the current open txg without
1082 * blocking, returns immediately with ERESTART. This should be used
1083 * whenever you're holding locks. On an ERESTART error, the caller
1084 * should drop locks, do a dmu_tx_wait(tx), and try again.
1086 * (3) A specific txg. Use this if you need to ensure that multiple
1087 * transactions all sync in the same txg. Like TXG_NOWAIT, it
1088 * returns ERESTART if it can't assign you into the requested txg.
1091 dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how)
1093 hrtime_t before, after;
1096 ASSERT(tx->tx_txg == 0);
1097 ASSERT(txg_how != 0);
1098 ASSERT(!dsl_pool_sync_context(tx->tx_pool));
1100 before = gethrtime();
1102 while ((err = dmu_tx_try_assign(tx, txg_how)) != 0) {
1103 dmu_tx_unassign(tx);
1105 if (err != ERESTART || txg_how != TXG_WAIT)
1111 txg_rele_to_quiesce(&tx->tx_txgh);
1113 after = gethrtime();
1115 dsl_pool_tx_assign_add_usecs(tx->tx_pool,
1116 (after - before) / NSEC_PER_USEC);
1122 dmu_tx_wait(dmu_tx_t *tx)
1124 spa_t *spa = tx->tx_pool->dp_spa;
1126 ASSERT(tx->tx_txg == 0);
1129 * It's possible that the pool has become active after this thread
1130 * has tried to obtain a tx. If that's the case then his
1131 * tx_lasttried_txg would not have been assigned.
1133 if (spa_suspended(spa) || tx->tx_lasttried_txg == 0) {
1134 txg_wait_synced(tx->tx_pool, spa_last_synced_txg(spa) + 1);
1135 } else if (tx->tx_needassign_txh) {
1136 dnode_t *dn = tx->tx_needassign_txh->txh_dnode;
1138 mutex_enter(&dn->dn_mtx);
1139 while (dn->dn_assigned_txg == tx->tx_lasttried_txg - 1)
1140 cv_wait(&dn->dn_notxholds, &dn->dn_mtx);
1141 mutex_exit(&dn->dn_mtx);
1142 tx->tx_needassign_txh = NULL;
1144 txg_wait_open(tx->tx_pool, tx->tx_lasttried_txg + 1);
1149 dmu_tx_willuse_space(dmu_tx_t *tx, int64_t delta)
1152 if (tx->tx_dir == NULL || delta == 0)
1156 ASSERT3U(refcount_count(&tx->tx_space_written) + delta, <=,
1157 tx->tx_space_towrite);
1158 (void) refcount_add_many(&tx->tx_space_written, delta, NULL);
1160 (void) refcount_add_many(&tx->tx_space_freed, -delta, NULL);
1166 dmu_tx_commit(dmu_tx_t *tx)
1170 ASSERT(tx->tx_txg != 0);
1172 while ((txh = list_head(&tx->tx_holds))) {
1173 dnode_t *dn = txh->txh_dnode;
1175 list_remove(&tx->tx_holds, txh);
1176 kmem_free(txh, sizeof (dmu_tx_hold_t));
1179 mutex_enter(&dn->dn_mtx);
1180 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg);
1182 if (refcount_remove(&dn->dn_tx_holds, tx) == 0) {
1183 dn->dn_assigned_txg = 0;
1184 cv_broadcast(&dn->dn_notxholds);
1186 mutex_exit(&dn->dn_mtx);
1190 if (tx->tx_tempreserve_cookie)
1191 dsl_dir_tempreserve_clear(tx->tx_tempreserve_cookie, tx);
1193 if (!list_is_empty(&tx->tx_callbacks))
1194 txg_register_callbacks(&tx->tx_txgh, &tx->tx_callbacks);
1196 if (tx->tx_anyobj == FALSE)
1197 txg_rele_to_sync(&tx->tx_txgh);
1199 list_destroy(&tx->tx_callbacks);
1200 list_destroy(&tx->tx_holds);
1202 dprintf("towrite=%llu written=%llu tofree=%llu freed=%llu\n",
1203 tx->tx_space_towrite, refcount_count(&tx->tx_space_written),
1204 tx->tx_space_tofree, refcount_count(&tx->tx_space_freed));
1205 refcount_destroy_many(&tx->tx_space_written,
1206 refcount_count(&tx->tx_space_written));
1207 refcount_destroy_many(&tx->tx_space_freed,
1208 refcount_count(&tx->tx_space_freed));
1210 kmem_free(tx, sizeof (dmu_tx_t));
1214 dmu_tx_abort(dmu_tx_t *tx)
1218 ASSERT(tx->tx_txg == 0);
1220 while ((txh = list_head(&tx->tx_holds))) {
1221 dnode_t *dn = txh->txh_dnode;
1223 list_remove(&tx->tx_holds, txh);
1224 kmem_free(txh, sizeof (dmu_tx_hold_t));
1230 * Call any registered callbacks with an error code.
1232 if (!list_is_empty(&tx->tx_callbacks))
1233 dmu_tx_do_callbacks(&tx->tx_callbacks, ECANCELED);
1235 list_destroy(&tx->tx_callbacks);
1236 list_destroy(&tx->tx_holds);
1238 refcount_destroy_many(&tx->tx_space_written,
1239 refcount_count(&tx->tx_space_written));
1240 refcount_destroy_many(&tx->tx_space_freed,
1241 refcount_count(&tx->tx_space_freed));
1243 kmem_free(tx, sizeof (dmu_tx_t));
1247 dmu_tx_get_txg(dmu_tx_t *tx)
1249 ASSERT(tx->tx_txg != 0);
1250 return (tx->tx_txg);
1254 dmu_tx_callback_register(dmu_tx_t *tx, dmu_tx_callback_func_t *func, void *data)
1256 dmu_tx_callback_t *dcb;
1258 dcb = kmem_alloc(sizeof (dmu_tx_callback_t), KM_PUSHPAGE);
1260 dcb->dcb_func = func;
1261 dcb->dcb_data = data;
1263 list_insert_tail(&tx->tx_callbacks, dcb);
1267 * Call all the commit callbacks on a list, with a given error code.
1270 dmu_tx_do_callbacks(list_t *cb_list, int error)
1272 dmu_tx_callback_t *dcb;
1274 while ((dcb = list_head(cb_list))) {
1275 list_remove(cb_list, dcb);
1276 dcb->dcb_func(dcb->dcb_data, error);
1277 kmem_free(dcb, sizeof (dmu_tx_callback_t));
1282 * Interface to hold a bunch of attributes.
1283 * used for creating new files.
1284 * attrsize is the total size of all attributes
1285 * to be added during object creation
1287 * For updating/adding a single attribute dmu_tx_hold_sa() should be used.
1291 * hold necessary attribute name for attribute registration.
1292 * should be a very rare case where this is needed. If it does
1293 * happen it would only happen on the first write to the file system.
1296 dmu_tx_sa_registration_hold(sa_os_t *sa, dmu_tx_t *tx)
1300 if (!sa->sa_need_attr_registration)
1303 for (i = 0; i != sa->sa_num_attrs; i++) {
1304 if (!sa->sa_attr_table[i].sa_registered) {
1305 if (sa->sa_reg_attr_obj)
1306 dmu_tx_hold_zap(tx, sa->sa_reg_attr_obj,
1307 B_TRUE, sa->sa_attr_table[i].sa_name);
1309 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT,
1310 B_TRUE, sa->sa_attr_table[i].sa_name);
1317 dmu_tx_hold_spill(dmu_tx_t *tx, uint64_t object)
1322 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, object,
1327 dn = txh->txh_dnode;
1332 /* If blkptr doesn't exist then add space to towrite */
1333 if (!(dn->dn_phys->dn_flags & DNODE_FLAG_SPILL_BLKPTR)) {
1334 txh->txh_space_towrite += SPA_MAXBLOCKSIZE;
1338 bp = &dn->dn_phys->dn_spill;
1339 if (dsl_dataset_block_freeable(dn->dn_objset->os_dsl_dataset,
1341 txh->txh_space_tooverwrite += SPA_MAXBLOCKSIZE;
1343 txh->txh_space_towrite += SPA_MAXBLOCKSIZE;
1344 if (!BP_IS_HOLE(bp))
1345 txh->txh_space_tounref += SPA_MAXBLOCKSIZE;
1350 dmu_tx_hold_sa_create(dmu_tx_t *tx, int attrsize)
1352 sa_os_t *sa = tx->tx_objset->os_sa;
1354 dmu_tx_hold_bonus(tx, DMU_NEW_OBJECT);
1356 if (tx->tx_objset->os_sa->sa_master_obj == 0)
1359 if (tx->tx_objset->os_sa->sa_layout_attr_obj)
1360 dmu_tx_hold_zap(tx, sa->sa_layout_attr_obj, B_TRUE, NULL);
1362 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_LAYOUTS);
1363 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_REGISTRY);
1364 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL);
1365 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL);
1368 dmu_tx_sa_registration_hold(sa, tx);
1370 if (attrsize <= DN_MAX_BONUSLEN && !sa->sa_force_spill)
1373 (void) dmu_tx_hold_object_impl(tx, tx->tx_objset, DMU_NEW_OBJECT,
1380 * dmu_tx_hold_sa(dmu_tx_t *tx, sa_handle_t *, attribute, add, size)
1382 * variable_size is the total size of all variable sized attributes
1383 * passed to this function. It is not the total size of all
1384 * variable size attributes that *may* exist on this object.
1387 dmu_tx_hold_sa(dmu_tx_t *tx, sa_handle_t *hdl, boolean_t may_grow)
1390 sa_os_t *sa = tx->tx_objset->os_sa;
1392 ASSERT(hdl != NULL);
1394 object = sa_handle_object(hdl);
1396 dmu_tx_hold_bonus(tx, object);
1398 if (tx->tx_objset->os_sa->sa_master_obj == 0)
1401 if (tx->tx_objset->os_sa->sa_reg_attr_obj == 0 ||
1402 tx->tx_objset->os_sa->sa_layout_attr_obj == 0) {
1403 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_LAYOUTS);
1404 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_REGISTRY);
1405 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL);
1406 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL);
1409 dmu_tx_sa_registration_hold(sa, tx);
1411 if (may_grow && tx->tx_objset->os_sa->sa_layout_attr_obj)
1412 dmu_tx_hold_zap(tx, sa->sa_layout_attr_obj, B_TRUE, NULL);
1414 if (sa->sa_force_spill || may_grow || hdl->sa_spill) {
1415 ASSERT(tx->tx_txg == 0);
1416 dmu_tx_hold_spill(tx, object);
1418 dmu_buf_impl_t *db = (dmu_buf_impl_t *)hdl->sa_bonus;
1423 if (dn->dn_have_spill) {
1424 ASSERT(tx->tx_txg == 0);
1425 dmu_tx_hold_spill(tx, object);
1434 dmu_tx_ksp = kstat_create("zfs", 0, "dmu_tx", "misc",
1435 KSTAT_TYPE_NAMED, sizeof (dmu_tx_stats) / sizeof (kstat_named_t),
1436 KSTAT_FLAG_VIRTUAL);
1438 if (dmu_tx_ksp != NULL) {
1439 dmu_tx_ksp->ks_data = &dmu_tx_stats;
1440 kstat_install(dmu_tx_ksp);
1447 if (dmu_tx_ksp != NULL) {
1448 kstat_delete(dmu_tx_ksp);
1453 #if defined(_KERNEL) && defined(HAVE_SPL)
1454 EXPORT_SYMBOL(dmu_tx_create);
1455 EXPORT_SYMBOL(dmu_tx_hold_write);
1456 EXPORT_SYMBOL(dmu_tx_hold_free);
1457 EXPORT_SYMBOL(dmu_tx_hold_zap);
1458 EXPORT_SYMBOL(dmu_tx_hold_bonus);
1459 EXPORT_SYMBOL(dmu_tx_abort);
1460 EXPORT_SYMBOL(dmu_tx_assign);
1461 EXPORT_SYMBOL(dmu_tx_wait);
1462 EXPORT_SYMBOL(dmu_tx_commit);
1463 EXPORT_SYMBOL(dmu_tx_get_txg);
1464 EXPORT_SYMBOL(dmu_tx_callback_register);
1465 EXPORT_SYMBOL(dmu_tx_do_callbacks);
1466 EXPORT_SYMBOL(dmu_tx_hold_spill);
1467 EXPORT_SYMBOL(dmu_tx_hold_sa_create);
1468 EXPORT_SYMBOL(dmu_tx_hold_sa);