From owner-svn-src-stable-10@freebsd.org Sat Oct 29 08:54:20 2016 Return-Path: Delivered-To: svn-src-stable-10@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 2A80FC24897; Sat, 29 Oct 2016 08:54:20 +0000 (UTC) (envelope-from mav@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id ECCEDA12; Sat, 29 Oct 2016 08:54:19 +0000 (UTC) (envelope-from mav@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id u9T8sJ9S001374; Sat, 29 Oct 2016 08:54:19 GMT (envelope-from mav@FreeBSD.org) Received: (from mav@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id u9T8sIXH001365; Sat, 29 Oct 2016 08:54:18 GMT (envelope-from mav@FreeBSD.org) Message-Id: <201610290854.u9T8sIXH001365@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: mav set sender to mav@FreeBSD.org using -f From: Alexander Motin Date: Sat, 29 Oct 2016 08:54:18 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-10@freebsd.org Subject: svn commit: r308083 - in stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs: . sys X-SVN-Group: stable-10 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-stable-10@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: SVN commit messages for only the 10-stable src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 29 Oct 2016 08:54:20 -0000 Author: mav Date: Sat Oct 29 08:54:18 2016 New Revision: 308083 URL: https://svnweb.freebsd.org/changeset/base/308083 Log: MFC r306424: MFV r306422: 7254 ztest failed assertion in ztest_dataset_dirobj_verify: dirobjs + 1 == usedo bjs dsl_dataset_space is looking at the ds_bp's fill count while dmu_objset_write_ready() is concurrently modifying it. This fix adds an rrwlock to protect the ds_bp. Closes #180 Reviewed by: George Wilson Reviewed by: Prakash Surya Reviewed by: Matthew Ahrens Reviewed by: Steve Gonczi Author: Paul Dagnelie Modified: stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dbuf.c stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_objset.c stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_destroy.c stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_pool.c stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_scan.c stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_objset.h stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dataset.h Directory Properties: stable/10/ (props changed) Modified: stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dbuf.c ============================================================================== --- stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dbuf.c Sat Oct 29 08:53:38 2016 (r308082) +++ stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dbuf.c Sat Oct 29 08:54:18 2016 (r308083) @@ -1482,10 +1482,18 @@ dbuf_dirty(dmu_buf_impl_t *db, dmu_tx_t * objects may be dirtied in syncing context, but only if they * were already pre-dirtied in open context. */ +#ifdef DEBUG + if (dn->dn_objset->os_dsl_dataset != NULL) { + rrw_enter(&dn->dn_objset->os_dsl_dataset->ds_bp_rwlock, + RW_READER, FTAG); + } ASSERT(!dmu_tx_is_syncing(tx) || BP_IS_HOLE(dn->dn_objset->os_rootbp) || DMU_OBJECT_IS_SPECIAL(dn->dn_object) || dn->dn_objset->os_dsl_dataset == NULL); + if (dn->dn_objset->os_dsl_dataset != NULL) + rrw_exit(&dn->dn_objset->os_dsl_dataset->ds_bp_rwlock, FTAG); +#endif /* * We make this assert for private objects as well, but after we * check if we're already dirty. They are allowed to re-dirty @@ -1510,12 +1518,21 @@ dbuf_dirty(dmu_buf_impl_t *db, dmu_tx_t * Don't set dirtyctx to SYNC if we're just modifying this as we * initialize the objset. */ - if (dn->dn_dirtyctx == DN_UNDIRTIED && - !BP_IS_HOLE(dn->dn_objset->os_rootbp)) { - dn->dn_dirtyctx = - (dmu_tx_is_syncing(tx) ? DN_DIRTY_SYNC : DN_DIRTY_OPEN); - ASSERT(dn->dn_dirtyctx_firstset == NULL); - dn->dn_dirtyctx_firstset = kmem_alloc(1, KM_SLEEP); + if (dn->dn_dirtyctx == DN_UNDIRTIED) { + if (dn->dn_objset->os_dsl_dataset != NULL) { + rrw_enter(&dn->dn_objset->os_dsl_dataset->ds_bp_rwlock, + RW_READER, FTAG); + } + if (!BP_IS_HOLE(dn->dn_objset->os_rootbp)) { + dn->dn_dirtyctx = (dmu_tx_is_syncing(tx) ? + DN_DIRTY_SYNC : DN_DIRTY_OPEN); + ASSERT(dn->dn_dirtyctx_firstset == NULL); + dn->dn_dirtyctx_firstset = kmem_alloc(1, KM_SLEEP); + } + if (dn->dn_objset->os_dsl_dataset != NULL) { + rrw_exit(&dn->dn_objset->os_dsl_dataset->ds_bp_rwlock, + FTAG); + } } mutex_exit(&dn->dn_mtx); @@ -1560,8 +1577,14 @@ dbuf_dirty(dmu_buf_impl_t *db, dmu_tx_t * this assertion only if we're not already dirty. */ os = dn->dn_objset; +#ifdef DEBUG + if (dn->dn_objset->os_dsl_dataset != NULL) + rrw_enter(&os->os_dsl_dataset->ds_bp_rwlock, RW_READER, FTAG); ASSERT(!dmu_tx_is_syncing(tx) || DMU_OBJECT_IS_SPECIAL(dn->dn_object) || os->os_dsl_dataset == NULL || BP_IS_HOLE(os->os_rootbp)); + if (dn->dn_objset->os_dsl_dataset != NULL) + rrw_exit(&os->os_dsl_dataset->ds_bp_rwlock, FTAG); +#endif ASSERT(db->db.db_size != 0); dprintf_dbuf(db, "size=%llx\n", (u_longlong_t)db->db.db_size); Modified: stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_objset.c ============================================================================== --- stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_objset.c Sat Oct 29 08:53:38 2016 (r308082) +++ stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_objset.c Sat Oct 29 08:54:18 2016 (r308083) @@ -489,8 +489,10 @@ dmu_objset_from_ds(dsl_dataset_t *ds, ob mutex_enter(&ds->ds_opening_lock); if (ds->ds_objset == NULL) { objset_t *os; + rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); err = dmu_objset_open_impl(dsl_dataset_get_spa(ds), ds, dsl_dataset_get_blkptr(ds), &os); + rrw_exit(&ds->ds_bp_rwlock, FTAG); if (err == 0) { mutex_enter(&ds->ds_lock); @@ -876,9 +878,11 @@ dmu_objset_create_sync(void *arg, dmu_tx doca->doca_cred, tx); VERIFY0(dsl_dataset_hold_obj(pdd->dd_pool, obj, FTAG, &ds)); + rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); bp = dsl_dataset_get_blkptr(ds); os = dmu_objset_create_impl(pdd->dd_pool->dp_spa, ds, bp, doca->doca_type, tx); + rrw_exit(&ds->ds_bp_rwlock, FTAG); if (doca->doca_userfunc != NULL) { doca->doca_userfunc(os, doca->doca_userarg, @@ -1051,7 +1055,6 @@ dmu_objset_write_ready(zio_t *zio, arc_b dnode_phys_t *dnp = &os->os_phys->os_meta_dnode; ASSERT(!BP_IS_EMBEDDED(bp)); - ASSERT3P(bp, ==, os->os_rootbp); ASSERT3U(BP_GET_TYPE(bp), ==, DMU_OT_OBJSET); ASSERT0(BP_GET_LEVEL(bp)); @@ -1064,6 +1067,11 @@ dmu_objset_write_ready(zio_t *zio, arc_b bp->blk_fill = 0; for (int i = 0; i < dnp->dn_nblkptr; i++) bp->blk_fill += BP_GET_FILL(&dnp->dn_blkptr[i]); + if (os->os_dsl_dataset != NULL) + rrw_enter(&os->os_dsl_dataset->ds_bp_rwlock, RW_WRITER, FTAG); + *os->os_rootbp = *bp; + if (os->os_dsl_dataset != NULL) + rrw_exit(&os->os_dsl_dataset->ds_bp_rwlock, FTAG); } /* ARGSUSED */ @@ -1083,6 +1091,7 @@ dmu_objset_write_done(zio_t *zio, arc_bu (void) dsl_dataset_block_kill(ds, bp_orig, tx, B_TRUE); dsl_dataset_block_born(ds, bp, tx); } + kmem_free(bp, sizeof (*bp)); } /* called from dsl */ @@ -1096,6 +1105,8 @@ dmu_objset_sync(objset_t *os, zio_t *pio list_t *list; list_t *newlist = NULL; dbuf_dirty_record_t *dr; + blkptr_t *blkptr_copy = kmem_alloc(sizeof (*os->os_rootbp), KM_SLEEP); + *blkptr_copy = *os->os_rootbp; dprintf_ds(os->os_dsl_dataset, "txg=%llu\n", tx->tx_txg); @@ -1123,7 +1134,7 @@ dmu_objset_sync(objset_t *os, zio_t *pio dmu_write_policy(os, NULL, 0, 0, &zp); zio = arc_write(pio, os->os_spa, tx->tx_txg, - os->os_rootbp, os->os_phys_buf, DMU_OS_IS_L2CACHEABLE(os), + blkptr_copy, os->os_phys_buf, DMU_OS_IS_L2CACHEABLE(os), &zp, dmu_objset_write_ready, NULL, NULL, dmu_objset_write_done, os, ZIO_PRIORITY_ASYNC_WRITE, ZIO_FLAG_MUSTSUCCEED, &zb); Modified: stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c ============================================================================== --- stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c Sat Oct 29 08:53:38 2016 (r308082) +++ stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c Sat Oct 29 08:54:18 2016 (r308083) @@ -1510,10 +1510,12 @@ dmu_recv_begin_sync(void *arg, dmu_tx_t * If we actually created a non-clone, we need to create the * objset in our new dataset. */ + rrw_enter(&newds->ds_bp_rwlock, RW_READER, FTAG); if (BP_IS_HOLE(dsl_dataset_get_blkptr(newds))) { (void) dmu_objset_create_impl(dp->dp_spa, newds, dsl_dataset_get_blkptr(newds), drrb->drr_type, tx); } + rrw_exit(&newds->ds_bp_rwlock, FTAG); drba->drba_cookie->drc_ds = newds; @@ -1656,7 +1658,9 @@ dmu_recv_resume_begin_sync(void *arg, dm dmu_buf_will_dirty(ds->ds_dbuf, tx); dsl_dataset_phys(ds)->ds_flags |= DS_FLAG_INCONSISTENT; + rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); ASSERT(!BP_IS_HOLE(dsl_dataset_get_blkptr(ds))); + rrw_exit(&ds->ds_bp_rwlock, FTAG); drba->drba_cookie->drc_ds = ds; Modified: stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c ============================================================================== --- stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c Sat Oct 29 08:53:38 2016 (r308082) +++ stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c Sat Oct 29 08:54:18 2016 (r308083) @@ -312,6 +312,7 @@ dsl_dataset_evict(void *dbu) mutex_destroy(&ds->ds_opening_lock); mutex_destroy(&ds->ds_sendstream_lock); refcount_destroy(&ds->ds_longholds); + rrw_destroy(&ds->ds_bp_rwlock); kmem_free(ds, sizeof (dsl_dataset_t)); } @@ -441,6 +442,7 @@ dsl_dataset_hold_obj(dsl_pool_t *dp, uin mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL); mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL); mutex_init(&ds->ds_sendstream_lock, NULL, MUTEX_DEFAULT, NULL); + rrw_init(&ds->ds_bp_rwlock, B_FALSE); refcount_create(&ds->ds_longholds); bplist_create(&ds->ds_pending_deadlist); @@ -831,7 +833,9 @@ dsl_dataset_create_sync_dd(dsl_dir_t *dd dsl_dataset_phys(origin)->ds_compressed_bytes; dsphys->ds_uncompressed_bytes = dsl_dataset_phys(origin)->ds_uncompressed_bytes; + rrw_enter(&origin->ds_bp_rwlock, RW_READER, FTAG); dsphys->ds_bp = dsl_dataset_phys(origin)->ds_bp; + rrw_exit(&origin->ds_bp_rwlock, FTAG); /* * Inherit flags that describe the dataset's contents @@ -1389,7 +1393,9 @@ dsl_dataset_snapshot_sync_impl(dsl_datas dsphys->ds_uncompressed_bytes = dsl_dataset_phys(ds)->ds_uncompressed_bytes; dsphys->ds_flags = dsl_dataset_phys(ds)->ds_flags; + rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); dsphys->ds_bp = dsl_dataset_phys(ds)->ds_bp; + rrw_exit(&ds->ds_bp_rwlock, FTAG); dmu_buf_rele(dbuf, FTAG); for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { @@ -1981,7 +1987,9 @@ dsl_dataset_space(dsl_dataset_t *ds, else *availbytesp = 0; } + rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); *usedobjsp = BP_GET_FILL(&dsl_dataset_phys(ds)->ds_bp); + rrw_exit(&ds->ds_bp_rwlock, FTAG); *availobjsp = DN_MAX_OBJECT - *usedobjsp; } @@ -1989,12 +1997,15 @@ boolean_t dsl_dataset_modified_since_snap(dsl_dataset_t *ds, dsl_dataset_t *snap) { dsl_pool_t *dp = ds->ds_dir->dd_pool; + uint64_t birth; ASSERT(dsl_pool_config_held(dp)); if (snap == NULL) return (B_FALSE); - if (dsl_dataset_phys(ds)->ds_bp.blk_birth > - dsl_dataset_phys(snap)->ds_creation_txg) { + rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); + birth = dsl_dataset_get_blkptr(ds)->blk_birth; + rrw_exit(&ds->ds_bp_rwlock, FTAG); + if (birth > dsl_dataset_phys(snap)->ds_creation_txg) { objset_t *os, *os_snap; /* * It may be that only the ZIL differs, because it was @@ -3058,11 +3069,15 @@ dsl_dataset_clone_swap_sync_impl(dsl_dat /* swap blkptrs */ { + rrw_enter(&clone->ds_bp_rwlock, RW_WRITER, FTAG); + rrw_enter(&origin_head->ds_bp_rwlock, RW_WRITER, FTAG); blkptr_t tmp; tmp = dsl_dataset_phys(origin_head)->ds_bp; dsl_dataset_phys(origin_head)->ds_bp = dsl_dataset_phys(clone)->ds_bp; dsl_dataset_phys(clone)->ds_bp = tmp; + rrw_exit(&origin_head->ds_bp_rwlock, FTAG); + rrw_exit(&clone->ds_bp_rwlock, FTAG); } /* set dd_*_bytes */ Modified: stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_destroy.c ============================================================================== --- stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_destroy.c Sat Oct 29 08:53:38 2016 (r308082) +++ stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_destroy.c Sat Oct 29 08:54:18 2016 (r308083) @@ -246,7 +246,9 @@ dsl_destroy_snapshot_sync_impl(dsl_datas uint64_t obj; ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock)); + rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); ASSERT3U(dsl_dataset_phys(ds)->ds_bp.blk_birth, <=, tx->tx_txg); + rrw_exit(&ds->ds_bp_rwlock, FTAG); ASSERT(refcount_is_zero(&ds->ds_longholds)); if (defer && @@ -720,7 +722,9 @@ dsl_destroy_head_sync_impl(dsl_dataset_t ASSERT3U(dsl_dataset_phys(ds)->ds_num_children, <=, 1); ASSERT(ds->ds_prev == NULL || dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj != ds->ds_object); + rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); ASSERT3U(dsl_dataset_phys(ds)->ds_bp.blk_birth, <=, tx->tx_txg); + rrw_exit(&ds->ds_bp_rwlock, FTAG); ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock)); /* We need to log before removing it from the namespace. */ @@ -812,10 +816,12 @@ dsl_destroy_head_sync_impl(dsl_dataset_t ASSERT(!DS_UNIQUE_IS_ACCURATE(ds) || dsl_dataset_phys(ds)->ds_unique_bytes == used); + rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); bptree_add(mos, dp->dp_bptree_obj, &dsl_dataset_phys(ds)->ds_bp, dsl_dataset_phys(ds)->ds_prev_snap_txg, used, comp, uncomp, tx); + rrw_exit(&ds->ds_bp_rwlock, FTAG); dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, -used, -comp, -uncomp, tx); dsl_dir_diduse_space(dp->dp_free_dir, DD_USED_HEAD, Modified: stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_pool.c ============================================================================== --- stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_pool.c Sat Oct 29 08:53:38 2016 (r308082) +++ stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_pool.c Sat Oct 29 08:54:18 2016 (r308083) @@ -20,7 +20,7 @@ */ /* * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. - * Copyright (c) 2011, 2014 by Delphix. All rights reserved. + * Copyright (c) 2011, 2015 by Delphix. All rights reserved. * Copyright (c) 2013 Steven Hartland. All rights reserved. * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved. * Copyright (c) 2014 Integros [integros.com] @@ -497,8 +497,10 @@ dsl_pool_create(spa_t *spa, nvlist_t *zp /* create the root objset */ VERIFY0(dsl_dataset_hold_obj(dp, obj, FTAG, &ds)); + rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); os = dmu_objset_create_impl(dp->dp_spa, ds, dsl_dataset_get_blkptr(ds), DMU_OST_ZFS, tx); + rrw_exit(&ds->ds_bp_rwlock, FTAG); #ifdef _KERNEL zfs_create_fs(os, kcred, zplprops, tx); #endif @@ -811,7 +813,9 @@ upgrade_clones_cb(dsl_pool_t *dp, dsl_da * The $ORIGIN can't have any data, or the accounting * will be wrong. */ + rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); ASSERT0(dsl_dataset_phys(prev)->ds_bp.blk_birth); + rrw_exit(&ds->ds_bp_rwlock, FTAG); /* The origin doesn't get attached to itself */ if (ds->ds_object == prev->ds_object) { Modified: stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_scan.c ============================================================================== --- stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_scan.c Sat Oct 29 08:53:38 2016 (r308082) +++ stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_scan.c Sat Oct 29 08:54:18 2016 (r308083) @@ -1122,7 +1122,9 @@ dsl_scan_visitds(dsl_scan_t *scn, uint64 * Iterate over the bps in this ds. */ dmu_buf_will_dirty(ds->ds_dbuf, tx); + rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); dsl_scan_visit_rootbp(scn, ds, &dsl_dataset_phys(ds)->ds_bp, tx); + rrw_exit(&ds->ds_bp_rwlock, FTAG); char *dsname = kmem_alloc(ZFS_MAX_DATASET_NAME_LEN, KM_SLEEP); dsl_dataset_name(ds, dsname); Modified: stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_objset.h ============================================================================== --- stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_objset.h Sat Oct 29 08:53:38 2016 (r308082) +++ stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_objset.h Sat Oct 29 08:54:18 2016 (r308083) @@ -20,7 +20,7 @@ */ /* * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. - * Copyright (c) 2012, 2014 by Delphix. All rights reserved. + * Copyright (c) 2012, 2015 by Delphix. All rights reserved. * Copyright (c) 2013 by Saso Kiselkov. All rights reserved. * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved. * Copyright (c) 2014 Integros [integros.com] @@ -101,9 +101,14 @@ struct objset { zfs_redundant_metadata_type_t os_redundant_metadata; int os_recordsize; + /* + * Pointer is constant; the blkptr it points to is protected by + * os_dsl_dataset->ds_bp_rwlock + */ + blkptr_t *os_rootbp; + /* no lock needed: */ struct dmu_tx *os_synctx; /* XXX sketchy */ - blkptr_t *os_rootbp; zil_header_t os_zil_header; list_t os_synced_dnodes; uint64_t os_flags; Modified: stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dataset.h ============================================================================== --- stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dataset.h Sat Oct 29 08:53:38 2016 (r308082) +++ stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dataset.h Sat Oct 29 08:54:18 2016 (r308083) @@ -39,6 +39,7 @@ #include #include #include +#include #include #ifdef __cplusplus @@ -141,6 +142,7 @@ typedef struct dsl_dataset_phys { typedef struct dsl_dataset { dmu_buf_user_t ds_dbu; + rrwlock_t ds_bp_rwlock; /* Protects ds_phys->ds_bp */ /* Immutable: */ struct dsl_dir *ds_dir;