From 8caa4bb0150b3a2dd48396aec3bd1f26931da878 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Arkadiusz=20Buba=C5=82a?= Date: Fri, 10 Nov 2017 22:37:10 +0100 Subject: [PATCH] Long hold the dataset during upgrade MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If the receive or rollback is performed while filesystem is upgrading the objset may be evicted in `dsl_dataset_clone_swap_sync_impl`. This will lead to NULL pointer dereference when upgrade tries to access evicted objset. This commit adds long hold of dataset during whole upgrade process. The receive and rollback will return an EBUSY error until the upgrade is not finished. Reviewed-by: Brian Behlendorf Signed-off-by: Arkadiusz Bubała Closes #5295 Closes #6837 --- module/zfs/dmu_objset.c | 18 ++++++++++++++---- module/zfs/zfs_ioctl.c | 8 ++++---- module/zfs/zfs_vfsops.c | 7 ++++++- 3 files changed, 24 insertions(+), 9 deletions(-) diff --git a/module/zfs/dmu_objset.c b/module/zfs/dmu_objset.c index babc396d7541..fc9cb242514f 100644 --- a/module/zfs/dmu_objset.c +++ b/module/zfs/dmu_objset.c @@ -28,6 +28,7 @@ * Copyright (c) 2015, STRATO AG, Inc. All rights reserved. * Copyright (c) 2016 Actifio, Inc. All rights reserved. * Copyright 2017 Nexenta Systems, Inc. + * Copyright (c) 2017 Open-E, Inc. All Rights Reserved. */ /* Portions Copyright 2010 Robert Milkowski */ @@ -79,6 +80,8 @@ int dmu_find_threads = 0; */ int dmu_rescan_dnode_threshold = 1 << DN_MAX_INDBLKSHIFT; +static char *upgrade_tag = "upgrade_tag"; + static void dmu_objset_find_dp_cb(void *arg); static void dmu_objset_upgrade(objset_t *os, dmu_objset_upgrade_cb_t cb); @@ -704,13 +707,12 @@ dmu_objset_own(const char *name, dmu_objset_type_t type, return (err); } - dsl_pool_rele(dp, FTAG); - /* user accounting requires the dataset to be decrypted */ if (dmu_objset_userobjspace_upgradable(*osp) && (ds->ds_dir->dd_crypto_obj == 0 || decrypt)) dmu_objset_userobjspace_upgrade(*osp); + dsl_pool_rele(dp, FTAG); return (0); } @@ -1311,6 +1313,7 @@ dmu_objset_upgrade_task_cb(void *data) os->os_upgrade_exit = B_TRUE; os->os_upgrade_id = 0; mutex_exit(&os->os_upgrade_lock); + dsl_dataset_long_rele(dmu_objset_ds(os), upgrade_tag); } static void @@ -1319,6 +1322,9 @@ dmu_objset_upgrade(objset_t *os, dmu_objset_upgrade_cb_t cb) if (os->os_upgrade_id != 0) return; + ASSERT(dsl_pool_config_held(dmu_objset_pool(os))); + dsl_dataset_long_hold(dmu_objset_ds(os), upgrade_tag); + mutex_enter(&os->os_upgrade_lock); if (os->os_upgrade_id == 0 && os->os_upgrade_status == 0) { os->os_upgrade_exit = B_FALSE; @@ -1326,8 +1332,10 @@ dmu_objset_upgrade(objset_t *os, dmu_objset_upgrade_cb_t cb) os->os_upgrade_id = taskq_dispatch( os->os_spa->spa_upgrade_taskq, dmu_objset_upgrade_task_cb, os, TQ_SLEEP); - if (os->os_upgrade_id == TASKQID_INVALID) + if (os->os_upgrade_id == TASKQID_INVALID) { + dsl_dataset_long_rele(dmu_objset_ds(os), upgrade_tag); os->os_upgrade_status = ENOMEM; + } } mutex_exit(&os->os_upgrade_lock); } @@ -1343,7 +1351,9 @@ dmu_objset_upgrade_stop(objset_t *os) os->os_upgrade_id = 0; mutex_exit(&os->os_upgrade_lock); - taskq_cancel_id(os->os_spa->spa_upgrade_taskq, id); + if ((taskq_cancel_id(os->os_spa->spa_upgrade_taskq, id)) == 0) { + dsl_dataset_long_rele(dmu_objset_ds(os), upgrade_tag); + } txg_wait_synced(os->os_spa->spa_dsl_pool, 0); } else { mutex_exit(&os->os_upgrade_lock); diff --git a/module/zfs/zfs_ioctl.c b/module/zfs/zfs_ioctl.c index 3c2c4f85090d..7bfa4cfd6098 100644 --- a/module/zfs/zfs_ioctl.c +++ b/module/zfs/zfs_ioctl.c @@ -5266,9 +5266,6 @@ zfs_ioc_userobjspace_upgrade(zfs_cmd_t *zc) if (error != 0) return (error); - dsl_dataset_long_hold(dmu_objset_ds(os), FTAG); - dsl_pool_rele(dmu_objset_pool(os), FTAG); - if (dmu_objset_userobjspace_upgradable(os)) { mutex_enter(&os->os_upgrade_lock); if (os->os_upgrade_id == 0) { @@ -5281,11 +5278,14 @@ zfs_ioc_userobjspace_upgrade(zfs_cmd_t *zc) mutex_exit(&os->os_upgrade_lock); } + dsl_pool_rele(dmu_objset_pool(os), FTAG); + taskq_wait_id(os->os_spa->spa_upgrade_taskq, os->os_upgrade_id); error = os->os_upgrade_status; + } else { + dsl_pool_rele(dmu_objset_pool(os), FTAG); } - dsl_dataset_long_rele(dmu_objset_ds(os), FTAG); dsl_dataset_rele_flags(dmu_objset_ds(os), DS_HOLD_FLAG_DECRYPT, FTAG); return (error); diff --git a/module/zfs/zfs_vfsops.c b/module/zfs/zfs_vfsops.c index 1559db35757c..66192e0e3276 100644 --- a/module/zfs/zfs_vfsops.c +++ b/module/zfs/zfs_vfsops.c @@ -835,8 +835,13 @@ zfs_fuid_overobjquota(zfsvfs_t *zfsvfs, boolean_t isgroup, uint64_t fuid) int err; if (!dmu_objset_userobjspace_present(zfsvfs->z_os)) { - if (dmu_objset_userobjspace_upgradable(zfsvfs->z_os)) + if (dmu_objset_userobjspace_upgradable(zfsvfs->z_os)) { + dsl_pool_config_enter( + dmu_objset_pool(zfsvfs->z_os), FTAG); dmu_objset_userobjspace_upgrade(zfsvfs->z_os); + dsl_pool_config_exit( + dmu_objset_pool(zfsvfs->z_os), FTAG); + } return (B_FALSE); }