diff options
Diffstat (limited to 'sys/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c')
-rw-r--r-- | sys/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c | 1215 |
1 files changed, 1215 insertions, 0 deletions
diff --git a/sys/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c b/sys/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c new file mode 100644 index 0000000..5e563b6 --- /dev/null +++ b/sys/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c @@ -0,0 +1,1215 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License (the "License"). + * You may not use this file except in compliance with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + */ +/* + * Copyright 2007 Sun Microsystems, Inc. All rights reserved. + * Use is subject to license terms. + */ + +#pragma ident "%Z%%M% %I% %E% SMI" + +#include <sys/dmu.h> +#include <sys/dmu_tx.h> +#include <sys/dsl_dataset.h> +#include <sys/dsl_dir.h> +#include <sys/dsl_prop.h> +#include <sys/dsl_synctask.h> +#include <sys/spa.h> +#include <sys/zap.h> +#include <sys/zio.h> +#include <sys/arc.h> +#include "zfs_namecheck.h" + +static uint64_t dsl_dir_estimated_space(dsl_dir_t *dd); +static void dsl_dir_set_reservation_sync(void *arg1, void *arg2, dmu_tx_t *tx); + + +/* ARGSUSED */ +static void +dsl_dir_evict(dmu_buf_t *db, void *arg) +{ + dsl_dir_t *dd = arg; + dsl_pool_t *dp = dd->dd_pool; + int t; + + for (t = 0; t < TXG_SIZE; t++) { + ASSERT(!txg_list_member(&dp->dp_dirty_dirs, dd, t)); + ASSERT(dd->dd_tempreserved[t] == 0); + ASSERT(dd->dd_space_towrite[t] == 0); + } + + ASSERT3U(dd->dd_used_bytes, ==, dd->dd_phys->dd_used_bytes); + + if (dd->dd_parent) + dsl_dir_close(dd->dd_parent, dd); + + spa_close(dd->dd_pool->dp_spa, dd); + + /* + * The props callback list should be empty since they hold the + * dir open. + */ + list_destroy(&dd->dd_prop_cbs); + mutex_destroy(&dd->dd_lock); + kmem_free(dd, sizeof (dsl_dir_t)); +} + +int +dsl_dir_open_obj(dsl_pool_t *dp, uint64_t ddobj, + const char *tail, void *tag, dsl_dir_t **ddp) +{ + dmu_buf_t *dbuf; + dsl_dir_t *dd; + int err; + + ASSERT(RW_LOCK_HELD(&dp->dp_config_rwlock) || + dsl_pool_sync_context(dp)); + + err = dmu_bonus_hold(dp->dp_meta_objset, ddobj, tag, &dbuf); + if (err) + return (err); + dd = dmu_buf_get_user(dbuf); +#ifdef ZFS_DEBUG + { + dmu_object_info_t doi; + dmu_object_info_from_db(dbuf, &doi); + ASSERT3U(doi.doi_type, ==, DMU_OT_DSL_DIR); + } +#endif + /* XXX assert bonus buffer size is correct */ + if (dd == NULL) { + dsl_dir_t *winner; + int err; + + dd = kmem_zalloc(sizeof (dsl_dir_t), KM_SLEEP); + dd->dd_object = ddobj; + dd->dd_dbuf = dbuf; + dd->dd_pool = dp; + dd->dd_phys = dbuf->db_data; + dd->dd_used_bytes = dd->dd_phys->dd_used_bytes; + mutex_init(&dd->dd_lock, NULL, MUTEX_DEFAULT, NULL); + + list_create(&dd->dd_prop_cbs, sizeof (dsl_prop_cb_record_t), + offsetof(dsl_prop_cb_record_t, cbr_node)); + + if (dd->dd_phys->dd_parent_obj) { + err = dsl_dir_open_obj(dp, dd->dd_phys->dd_parent_obj, + NULL, dd, &dd->dd_parent); + if (err) { + mutex_destroy(&dd->dd_lock); + kmem_free(dd, sizeof (dsl_dir_t)); + dmu_buf_rele(dbuf, tag); + return (err); + } + if (tail) { +#ifdef ZFS_DEBUG + uint64_t foundobj; + + err = zap_lookup(dp->dp_meta_objset, + dd->dd_parent->dd_phys-> + dd_child_dir_zapobj, + tail, sizeof (foundobj), 1, &foundobj); + ASSERT(err || foundobj == ddobj); +#endif + (void) strcpy(dd->dd_myname, tail); + } else { + err = zap_value_search(dp->dp_meta_objset, + dd->dd_parent->dd_phys-> + dd_child_dir_zapobj, + ddobj, dd->dd_myname); + } + if (err) { + dsl_dir_close(dd->dd_parent, dd); + mutex_destroy(&dd->dd_lock); + kmem_free(dd, sizeof (dsl_dir_t)); + dmu_buf_rele(dbuf, tag); + return (err); + } + } else { + (void) strcpy(dd->dd_myname, spa_name(dp->dp_spa)); + } + + winner = dmu_buf_set_user_ie(dbuf, dd, &dd->dd_phys, + dsl_dir_evict); + if (winner) { + if (dd->dd_parent) + dsl_dir_close(dd->dd_parent, dd); + mutex_destroy(&dd->dd_lock); + kmem_free(dd, sizeof (dsl_dir_t)); + dd = winner; + } else { + spa_open_ref(dp->dp_spa, dd); + } + } + + /* + * The dsl_dir_t has both open-to-close and instantiate-to-evict + * holds on the spa. We need the open-to-close holds because + * otherwise the spa_refcnt wouldn't change when we open a + * dir which the spa also has open, so we could incorrectly + * think it was OK to unload/export/destroy the pool. We need + * the instantiate-to-evict hold because the dsl_dir_t has a + * pointer to the dd_pool, which has a pointer to the spa_t. + */ + spa_open_ref(dp->dp_spa, tag); + ASSERT3P(dd->dd_pool, ==, dp); + ASSERT3U(dd->dd_object, ==, ddobj); + ASSERT3P(dd->dd_dbuf, ==, dbuf); + *ddp = dd; + return (0); +} + +void +dsl_dir_close(dsl_dir_t *dd, void *tag) +{ + dprintf_dd(dd, "%s\n", ""); + spa_close(dd->dd_pool->dp_spa, tag); + dmu_buf_rele(dd->dd_dbuf, tag); +} + +/* buf must be long enough (MAXNAMELEN + strlen(MOS_DIR_NAME) + 1 should do) */ +void +dsl_dir_name(dsl_dir_t *dd, char *buf) +{ + if (dd->dd_parent) { + dsl_dir_name(dd->dd_parent, buf); + (void) strcat(buf, "/"); + } else { + buf[0] = '\0'; + } + if (!MUTEX_HELD(&dd->dd_lock)) { + /* + * recursive mutex so that we can use + * dprintf_dd() with dd_lock held + */ + mutex_enter(&dd->dd_lock); + (void) strcat(buf, dd->dd_myname); + mutex_exit(&dd->dd_lock); + } else { + (void) strcat(buf, dd->dd_myname); + } +} + +/* Calculate name legnth, avoiding all the strcat calls of dsl_dir_name */ +int +dsl_dir_namelen(dsl_dir_t *dd) +{ + int result = 0; + + if (dd->dd_parent) { + /* parent's name + 1 for the "/" */ + result = dsl_dir_namelen(dd->dd_parent) + 1; + } + + if (!MUTEX_HELD(&dd->dd_lock)) { + /* see dsl_dir_name */ + mutex_enter(&dd->dd_lock); + result += strlen(dd->dd_myname); + mutex_exit(&dd->dd_lock); + } else { + result += strlen(dd->dd_myname); + } + + return (result); +} + +int +dsl_dir_is_private(dsl_dir_t *dd) +{ + int rv = FALSE; + + if (dd->dd_parent && dsl_dir_is_private(dd->dd_parent)) + rv = TRUE; + if (dataset_name_hidden(dd->dd_myname)) + rv = TRUE; + return (rv); +} + + +static int +getcomponent(const char *path, char *component, const char **nextp) +{ + char *p; + if (path == NULL) + return (ENOENT); + /* This would be a good place to reserve some namespace... */ + p = strpbrk(path, "/@"); + if (p && (p[1] == '/' || p[1] == '@')) { + /* two separators in a row */ + return (EINVAL); + } + if (p == NULL || p == path) { + /* + * if the first thing is an @ or /, it had better be an + * @ and it had better not have any more ats or slashes, + * and it had better have something after the @. + */ + if (p != NULL && + (p[0] != '@' || strpbrk(path+1, "/@") || p[1] == '\0')) + return (EINVAL); + if (strlen(path) >= MAXNAMELEN) + return (ENAMETOOLONG); + (void) strcpy(component, path); + p = NULL; + } else if (p[0] == '/') { + if (p-path >= MAXNAMELEN) + return (ENAMETOOLONG); + (void) strncpy(component, path, p - path); + component[p-path] = '\0'; + p++; + } else if (p[0] == '@') { + /* + * if the next separator is an @, there better not be + * any more slashes. + */ + if (strchr(path, '/')) + return (EINVAL); + if (p-path >= MAXNAMELEN) + return (ENAMETOOLONG); + (void) strncpy(component, path, p - path); + component[p-path] = '\0'; + } else { + ASSERT(!"invalid p"); + } + *nextp = p; + return (0); +} + +/* + * same as dsl_open_dir, ignore the first component of name and use the + * spa instead + */ +int +dsl_dir_open_spa(spa_t *spa, const char *name, void *tag, + dsl_dir_t **ddp, const char **tailp) +{ + char buf[MAXNAMELEN]; + const char *next, *nextnext = NULL; + int err; + dsl_dir_t *dd; + dsl_pool_t *dp; + uint64_t ddobj; + int openedspa = FALSE; + + dprintf("%s\n", name); + + err = getcomponent(name, buf, &next); + if (err) + return (err); + if (spa == NULL) { + err = spa_open(buf, &spa, FTAG); + if (err) { + dprintf("spa_open(%s) failed\n", buf); + return (err); + } + openedspa = TRUE; + + /* XXX this assertion belongs in spa_open */ + ASSERT(!dsl_pool_sync_context(spa_get_dsl(spa))); + } + + dp = spa_get_dsl(spa); + + rw_enter(&dp->dp_config_rwlock, RW_READER); + err = dsl_dir_open_obj(dp, dp->dp_root_dir_obj, NULL, tag, &dd); + if (err) { + rw_exit(&dp->dp_config_rwlock); + if (openedspa) + spa_close(spa, FTAG); + return (err); + } + + while (next != NULL) { + dsl_dir_t *child_ds; + err = getcomponent(next, buf, &nextnext); + if (err) + break; + ASSERT(next[0] != '\0'); + if (next[0] == '@') + break; + dprintf("looking up %s in obj%lld\n", + buf, dd->dd_phys->dd_child_dir_zapobj); + + err = zap_lookup(dp->dp_meta_objset, + dd->dd_phys->dd_child_dir_zapobj, + buf, sizeof (ddobj), 1, &ddobj); + if (err) { + if (err == ENOENT) + err = 0; + break; + } + + err = dsl_dir_open_obj(dp, ddobj, buf, tag, &child_ds); + if (err) + break; + dsl_dir_close(dd, tag); + dd = child_ds; + next = nextnext; + } + rw_exit(&dp->dp_config_rwlock); + + if (err) { + dsl_dir_close(dd, tag); + if (openedspa) + spa_close(spa, FTAG); + return (err); + } + + /* + * It's an error if there's more than one component left, or + * tailp==NULL and there's any component left. + */ + if (next != NULL && + (tailp == NULL || (nextnext && nextnext[0] != '\0'))) { + /* bad path name */ + dsl_dir_close(dd, tag); + dprintf("next=%p (%s) tail=%p\n", next, next?next:"", tailp); + err = ENOENT; + } + if (tailp) + *tailp = next; + if (openedspa) + spa_close(spa, FTAG); + *ddp = dd; + return (err); +} + +/* + * Return the dsl_dir_t, and possibly the last component which couldn't + * be found in *tail. Return NULL if the path is bogus, or if + * tail==NULL and we couldn't parse the whole name. (*tail)[0] == '@' + * means that the last component is a snapshot. + */ +int +dsl_dir_open(const char *name, void *tag, dsl_dir_t **ddp, const char **tailp) +{ + return (dsl_dir_open_spa(NULL, name, tag, ddp, tailp)); +} + +uint64_t +dsl_dir_create_sync(dsl_dir_t *pds, const char *name, dmu_tx_t *tx) +{ + objset_t *mos = pds->dd_pool->dp_meta_objset; + uint64_t ddobj; + dsl_dir_phys_t *dsphys; + dmu_buf_t *dbuf; + + ddobj = dmu_object_alloc(mos, DMU_OT_DSL_DIR, 0, + DMU_OT_DSL_DIR, sizeof (dsl_dir_phys_t), tx); + VERIFY(0 == zap_add(mos, pds->dd_phys->dd_child_dir_zapobj, + name, sizeof (uint64_t), 1, &ddobj, tx)); + VERIFY(0 == dmu_bonus_hold(mos, ddobj, FTAG, &dbuf)); + dmu_buf_will_dirty(dbuf, tx); + dsphys = dbuf->db_data; + + dsphys->dd_creation_time = gethrestime_sec(); + dsphys->dd_parent_obj = pds->dd_object; + dsphys->dd_props_zapobj = zap_create(mos, + DMU_OT_DSL_PROPS, DMU_OT_NONE, 0, tx); + dsphys->dd_child_dir_zapobj = zap_create(mos, + DMU_OT_DSL_DIR_CHILD_MAP, DMU_OT_NONE, 0, tx); + dmu_buf_rele(dbuf, FTAG); + + return (ddobj); +} + +/* ARGSUSED */ +int +dsl_dir_destroy_check(void *arg1, void *arg2, dmu_tx_t *tx) +{ + dsl_dir_t *dd = arg1; + dsl_pool_t *dp = dd->dd_pool; + objset_t *mos = dp->dp_meta_objset; + int err; + uint64_t count; + + /* + * There should be exactly two holds, both from + * dsl_dataset_destroy: one on the dd directory, and one on its + * head ds. Otherwise, someone is trying to lookup something + * inside this dir while we want to destroy it. The + * config_rwlock ensures that nobody else opens it after we + * check. + */ + if (dmu_buf_refcount(dd->dd_dbuf) > 2) + return (EBUSY); + + err = zap_count(mos, dd->dd_phys->dd_child_dir_zapobj, &count); + if (err) + return (err); + if (count != 0) + return (EEXIST); + + return (0); +} + +void +dsl_dir_destroy_sync(void *arg1, void *tag, dmu_tx_t *tx) +{ + dsl_dir_t *dd = arg1; + objset_t *mos = dd->dd_pool->dp_meta_objset; + uint64_t val, obj; + + ASSERT(RW_WRITE_HELD(&dd->dd_pool->dp_config_rwlock)); + ASSERT(dd->dd_phys->dd_head_dataset_obj == 0); + + /* Remove our reservation. */ + val = 0; + dsl_dir_set_reservation_sync(dd, &val, tx); + ASSERT3U(dd->dd_used_bytes, ==, 0); + ASSERT3U(dd->dd_phys->dd_reserved, ==, 0); + + VERIFY(0 == zap_destroy(mos, dd->dd_phys->dd_child_dir_zapobj, tx)); + VERIFY(0 == zap_destroy(mos, dd->dd_phys->dd_props_zapobj, tx)); + VERIFY(0 == zap_remove(mos, + dd->dd_parent->dd_phys->dd_child_dir_zapobj, dd->dd_myname, tx)); + + obj = dd->dd_object; + dsl_dir_close(dd, tag); + VERIFY(0 == dmu_object_free(mos, obj, tx)); +} + +void +dsl_dir_create_root(objset_t *mos, uint64_t *ddobjp, dmu_tx_t *tx) +{ + dsl_dir_phys_t *dsp; + dmu_buf_t *dbuf; + int error; + + *ddobjp = dmu_object_alloc(mos, DMU_OT_DSL_DIR, 0, + DMU_OT_DSL_DIR, sizeof (dsl_dir_phys_t), tx); + + error = zap_add(mos, DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_ROOT_DATASET, + sizeof (uint64_t), 1, ddobjp, tx); + ASSERT3U(error, ==, 0); + + VERIFY(0 == dmu_bonus_hold(mos, *ddobjp, FTAG, &dbuf)); + dmu_buf_will_dirty(dbuf, tx); + dsp = dbuf->db_data; + + dsp->dd_creation_time = gethrestime_sec(); + dsp->dd_props_zapobj = zap_create(mos, + DMU_OT_DSL_PROPS, DMU_OT_NONE, 0, tx); + dsp->dd_child_dir_zapobj = zap_create(mos, + DMU_OT_DSL_DIR_CHILD_MAP, DMU_OT_NONE, 0, tx); + + dmu_buf_rele(dbuf, FTAG); +} + +void +dsl_dir_stats(dsl_dir_t *dd, nvlist_t *nv) +{ + dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, + dsl_dir_space_available(dd, NULL, 0, TRUE)); + + mutex_enter(&dd->dd_lock); + dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED, dd->dd_used_bytes); + dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_QUOTA, + dd->dd_phys->dd_quota); + dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_RESERVATION, + dd->dd_phys->dd_reserved); + dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, + dd->dd_phys->dd_compressed_bytes == 0 ? 100 : + (dd->dd_phys->dd_uncompressed_bytes * 100 / + dd->dd_phys->dd_compressed_bytes)); + mutex_exit(&dd->dd_lock); + + if (dd->dd_phys->dd_clone_parent_obj) { + dsl_dataset_t *ds; + char buf[MAXNAMELEN]; + + rw_enter(&dd->dd_pool->dp_config_rwlock, RW_READER); + VERIFY(0 == dsl_dataset_open_obj(dd->dd_pool, + dd->dd_phys->dd_clone_parent_obj, + NULL, DS_MODE_NONE, FTAG, &ds)); + dsl_dataset_name(ds, buf); + dsl_dataset_close(ds, DS_MODE_NONE, FTAG); + rw_exit(&dd->dd_pool->dp_config_rwlock); + + dsl_prop_nvlist_add_string(nv, ZFS_PROP_ORIGIN, buf); + } +} + +void +dsl_dir_dirty(dsl_dir_t *dd, dmu_tx_t *tx) +{ + dsl_pool_t *dp = dd->dd_pool; + + ASSERT(dd->dd_phys); + + if (txg_list_add(&dp->dp_dirty_dirs, dd, tx->tx_txg) == 0) { + /* up the hold count until we can be written out */ + dmu_buf_add_ref(dd->dd_dbuf, dd); + } +} + +static int64_t +parent_delta(dsl_dir_t *dd, uint64_t used, int64_t delta) +{ + uint64_t old_accounted = MAX(used, dd->dd_phys->dd_reserved); + uint64_t new_accounted = MAX(used + delta, dd->dd_phys->dd_reserved); + return (new_accounted - old_accounted); +} + +void +dsl_dir_sync(dsl_dir_t *dd, dmu_tx_t *tx) +{ + ASSERT(dmu_tx_is_syncing(tx)); + + dmu_buf_will_dirty(dd->dd_dbuf, tx); + + mutex_enter(&dd->dd_lock); + ASSERT3U(dd->dd_tempreserved[tx->tx_txg&TXG_MASK], ==, 0); + dprintf_dd(dd, "txg=%llu towrite=%lluK\n", tx->tx_txg, + dd->dd_space_towrite[tx->tx_txg&TXG_MASK] / 1024); + dd->dd_space_towrite[tx->tx_txg&TXG_MASK] = 0; + dd->dd_phys->dd_used_bytes = dd->dd_used_bytes; + mutex_exit(&dd->dd_lock); + + /* release the hold from dsl_dir_dirty */ + dmu_buf_rele(dd->dd_dbuf, dd); +} + +static uint64_t +dsl_dir_estimated_space(dsl_dir_t *dd) +{ + int64_t space; + int i; + + ASSERT(MUTEX_HELD(&dd->dd_lock)); + + space = dd->dd_phys->dd_used_bytes; + ASSERT(space >= 0); + for (i = 0; i < TXG_SIZE; i++) { + space += dd->dd_space_towrite[i&TXG_MASK]; + ASSERT3U(dd->dd_space_towrite[i&TXG_MASK], >=, 0); + } + return (space); +} + +/* + * How much space would dd have available if ancestor had delta applied + * to it? If ondiskonly is set, we're only interested in what's + * on-disk, not estimated pending changes. + */ +uint64_t +dsl_dir_space_available(dsl_dir_t *dd, + dsl_dir_t *ancestor, int64_t delta, int ondiskonly) +{ + uint64_t parentspace, myspace, quota, used; + + /* + * If there are no restrictions otherwise, assume we have + * unlimited space available. + */ + quota = UINT64_MAX; + parentspace = UINT64_MAX; + + if (dd->dd_parent != NULL) { + parentspace = dsl_dir_space_available(dd->dd_parent, + ancestor, delta, ondiskonly); + } + + mutex_enter(&dd->dd_lock); + if (dd->dd_phys->dd_quota != 0) + quota = dd->dd_phys->dd_quota; + if (ondiskonly) { + used = dd->dd_used_bytes; + } else { + used = dsl_dir_estimated_space(dd); + } + if (dd == ancestor) + used += delta; + + if (dd->dd_parent == NULL) { + uint64_t poolsize = dsl_pool_adjustedsize(dd->dd_pool, FALSE); + quota = MIN(quota, poolsize); + } + + if (dd->dd_phys->dd_reserved > used && parentspace != UINT64_MAX) { + /* + * We have some space reserved, in addition to what our + * parent gave us. + */ + parentspace += dd->dd_phys->dd_reserved - used; + } + + if (used > quota) { + /* over quota */ + myspace = 0; + + /* + * While it's OK to be a little over quota, if + * we think we are using more space than there + * is in the pool (which is already 1.6% more than + * dsl_pool_adjustedsize()), something is very + * wrong. + */ + ASSERT3U(used, <=, spa_get_space(dd->dd_pool->dp_spa)); + } else { + /* + * the lesser of the space provided by our parent and + * the space left in our quota + */ + myspace = MIN(parentspace, quota - used); + } + + mutex_exit(&dd->dd_lock); + + return (myspace); +} + +struct tempreserve { + list_node_t tr_node; + dsl_dir_t *tr_ds; + uint64_t tr_size; +}; + +/* + * Reserve space in this dsl_dir, to be used in this tx's txg. + * After the space has been dirtied (and thus + * dsl_dir_willuse_space() has been called), the reservation should + * be canceled, using dsl_dir_tempreserve_clear(). + */ +static int +dsl_dir_tempreserve_impl(dsl_dir_t *dd, + uint64_t asize, boolean_t netfree, list_t *tr_list, dmu_tx_t *tx) +{ + uint64_t txg = tx->tx_txg; + uint64_t est_used, quota, parent_rsrv; + int edquot = EDQUOT; + int txgidx = txg & TXG_MASK; + int i; + struct tempreserve *tr; + + ASSERT3U(txg, !=, 0); + ASSERT3S(asize, >=, 0); + + mutex_enter(&dd->dd_lock); + /* + * Check against the dsl_dir's quota. We don't add in the delta + * when checking for over-quota because they get one free hit. + */ + est_used = dsl_dir_estimated_space(dd); + for (i = 0; i < TXG_SIZE; i++) + est_used += dd->dd_tempreserved[i]; + + quota = UINT64_MAX; + + if (dd->dd_phys->dd_quota) + quota = dd->dd_phys->dd_quota; + + /* + * If this transaction will result in a net free of space, we want + * to let it through, but we have to be careful: the space that it + * frees won't become available until *after* this txg syncs. + * Therefore, to ensure that it's possible to remove files from + * a full pool without inducing transient overcommits, we throttle + * netfree transactions against a quota that is slightly larger, + * but still within the pool's allocation slop. In cases where + * we're very close to full, this will allow a steady trickle of + * removes to get through. + */ + if (dd->dd_parent == NULL) { + uint64_t poolsize = dsl_pool_adjustedsize(dd->dd_pool, netfree); + if (poolsize < quota) { + quota = poolsize; + edquot = ENOSPC; + } + } else if (netfree) { + quota = UINT64_MAX; + } + + /* + * If they are requesting more space, and our current estimate + * is over quota. They get to try again unless the actual + * on-disk is over quota and there are no pending changes (which + * may free up space for us). + */ + if (asize > 0 && est_used > quota) { + if (dd->dd_space_towrite[txg & TXG_MASK] != 0 || + dd->dd_space_towrite[(txg-1) & TXG_MASK] != 0 || + dd->dd_space_towrite[(txg-2) & TXG_MASK] != 0 || + dd->dd_used_bytes < quota) + edquot = ERESTART; + dprintf_dd(dd, "failing: used=%lluK est_used = %lluK " + "quota=%lluK tr=%lluK err=%d\n", + dd->dd_used_bytes>>10, est_used>>10, + quota>>10, asize>>10, edquot); + mutex_exit(&dd->dd_lock); + return (edquot); + } + + /* We need to up our estimated delta before dropping dd_lock */ + dd->dd_tempreserved[txgidx] += asize; + + parent_rsrv = parent_delta(dd, est_used, asize); + mutex_exit(&dd->dd_lock); + + tr = kmem_alloc(sizeof (struct tempreserve), KM_SLEEP); + tr->tr_ds = dd; + tr->tr_size = asize; + list_insert_tail(tr_list, tr); + + /* see if it's OK with our parent */ + if (dd->dd_parent && parent_rsrv) { + return (dsl_dir_tempreserve_impl(dd->dd_parent, + parent_rsrv, netfree, tr_list, tx)); + } else { + return (0); + } +} + +/* + * Reserve space in this dsl_dir, to be used in this tx's txg. + * After the space has been dirtied (and thus + * dsl_dir_willuse_space() has been called), the reservation should + * be canceled, using dsl_dir_tempreserve_clear(). + */ +int +dsl_dir_tempreserve_space(dsl_dir_t *dd, uint64_t lsize, + uint64_t asize, uint64_t fsize, void **tr_cookiep, dmu_tx_t *tx) +{ + int err = 0; + list_t *tr_list; + + tr_list = kmem_alloc(sizeof (list_t), KM_SLEEP); + list_create(tr_list, sizeof (struct tempreserve), + offsetof(struct tempreserve, tr_node)); + ASSERT3S(asize, >=, 0); + ASSERT3S(fsize, >=, 0); + + err = dsl_dir_tempreserve_impl(dd, asize, fsize >= asize, + tr_list, tx); + + if (err == 0) { + struct tempreserve *tr; + + err = arc_tempreserve_space(lsize); + if (err == 0) { + tr = kmem_alloc(sizeof (struct tempreserve), KM_SLEEP); + tr->tr_ds = NULL; + tr->tr_size = lsize; + list_insert_tail(tr_list, tr); + } + } + + if (err) + dsl_dir_tempreserve_clear(tr_list, tx); + else + *tr_cookiep = tr_list; + return (err); +} + +/* + * Clear a temporary reservation that we previously made with + * dsl_dir_tempreserve_space(). + */ +void +dsl_dir_tempreserve_clear(void *tr_cookie, dmu_tx_t *tx) +{ + int txgidx = tx->tx_txg & TXG_MASK; + list_t *tr_list = tr_cookie; + struct tempreserve *tr; + + ASSERT3U(tx->tx_txg, !=, 0); + + while (tr = list_head(tr_list)) { + if (tr->tr_ds == NULL) { + arc_tempreserve_clear(tr->tr_size); + } else { + mutex_enter(&tr->tr_ds->dd_lock); + ASSERT3U(tr->tr_ds->dd_tempreserved[txgidx], >=, + tr->tr_size); + tr->tr_ds->dd_tempreserved[txgidx] -= tr->tr_size; + mutex_exit(&tr->tr_ds->dd_lock); + } + list_remove(tr_list, tr); + kmem_free(tr, sizeof (struct tempreserve)); + } + + kmem_free(tr_list, sizeof (list_t)); +} + +/* + * Call in open context when we think we're going to write/free space, + * eg. when dirtying data. Be conservative (ie. OK to write less than + * this or free more than this, but don't write more or free less). + */ +void +dsl_dir_willuse_space(dsl_dir_t *dd, int64_t space, dmu_tx_t *tx) +{ + int64_t parent_space; + uint64_t est_used; + + mutex_enter(&dd->dd_lock); + if (space > 0) + dd->dd_space_towrite[tx->tx_txg & TXG_MASK] += space; + + est_used = dsl_dir_estimated_space(dd); + parent_space = parent_delta(dd, est_used, space); + mutex_exit(&dd->dd_lock); + + /* Make sure that we clean up dd_space_to* */ + dsl_dir_dirty(dd, tx); + + /* XXX this is potentially expensive and unnecessary... */ + if (parent_space && dd->dd_parent) + dsl_dir_willuse_space(dd->dd_parent, parent_space, tx); +} + +/* call from syncing context when we actually write/free space for this dd */ +void +dsl_dir_diduse_space(dsl_dir_t *dd, + int64_t used, int64_t compressed, int64_t uncompressed, dmu_tx_t *tx) +{ + int64_t accounted_delta; + + ASSERT(dmu_tx_is_syncing(tx)); + + dsl_dir_dirty(dd, tx); + + mutex_enter(&dd->dd_lock); + accounted_delta = parent_delta(dd, dd->dd_used_bytes, used); + ASSERT(used >= 0 || dd->dd_used_bytes >= -used); + ASSERT(compressed >= 0 || + dd->dd_phys->dd_compressed_bytes >= -compressed); + ASSERT(uncompressed >= 0 || + dd->dd_phys->dd_uncompressed_bytes >= -uncompressed); + dd->dd_used_bytes += used; + dd->dd_phys->dd_uncompressed_bytes += uncompressed; + dd->dd_phys->dd_compressed_bytes += compressed; + mutex_exit(&dd->dd_lock); + + if (dd->dd_parent != NULL) { + dsl_dir_diduse_space(dd->dd_parent, + accounted_delta, compressed, uncompressed, tx); + } +} + +/* ARGSUSED */ +static int +dsl_dir_set_quota_check(void *arg1, void *arg2, dmu_tx_t *tx) +{ + dsl_dir_t *dd = arg1; + uint64_t *quotap = arg2; + uint64_t new_quota = *quotap; + int err = 0; + uint64_t towrite; + + if (new_quota == 0) + return (0); + + mutex_enter(&dd->dd_lock); + /* + * If we are doing the preliminary check in open context, and + * there are pending changes, then don't fail it, since the + * pending changes could under-estimat the amount of space to be + * freed up. + */ + towrite = dd->dd_space_towrite[0] + dd->dd_space_towrite[1] + + dd->dd_space_towrite[2] + dd->dd_space_towrite[3]; + if ((dmu_tx_is_syncing(tx) || towrite == 0) && + (new_quota < dd->dd_phys->dd_reserved || + new_quota < dsl_dir_estimated_space(dd))) { + err = ENOSPC; + } + mutex_exit(&dd->dd_lock); + return (err); +} + +static void +dsl_dir_set_quota_sync(void *arg1, void *arg2, dmu_tx_t *tx) +{ + dsl_dir_t *dd = arg1; + uint64_t *quotap = arg2; + uint64_t new_quota = *quotap; + + dmu_buf_will_dirty(dd->dd_dbuf, tx); + + mutex_enter(&dd->dd_lock); + dd->dd_phys->dd_quota = new_quota; + mutex_exit(&dd->dd_lock); +} + +int +dsl_dir_set_quota(const char *ddname, uint64_t quota) +{ + dsl_dir_t *dd; + int err; + + err = dsl_dir_open(ddname, FTAG, &dd, NULL); + if (err) + return (err); + /* + * If someone removes a file, then tries to set the quota, we + * want to make sure the file freeing takes effect. + */ + txg_wait_open(dd->dd_pool, 0); + + err = dsl_sync_task_do(dd->dd_pool, dsl_dir_set_quota_check, + dsl_dir_set_quota_sync, dd, "a, 0); + dsl_dir_close(dd, FTAG); + return (err); +} + +/* ARGSUSED */ +static int +dsl_dir_set_reservation_check(void *arg1, void *arg2, dmu_tx_t *tx) +{ + dsl_dir_t *dd = arg1; + uint64_t *reservationp = arg2; + uint64_t new_reservation = *reservationp; + uint64_t used, avail; + int64_t delta; + + if (new_reservation > INT64_MAX) + return (EOVERFLOW); + + /* + * If we are doing the preliminary check in open context, the + * space estimates may be inaccurate. + */ + if (!dmu_tx_is_syncing(tx)) + return (0); + + mutex_enter(&dd->dd_lock); + used = dd->dd_used_bytes; + delta = MAX(used, new_reservation) - + MAX(used, dd->dd_phys->dd_reserved); + mutex_exit(&dd->dd_lock); + + if (dd->dd_parent) { + avail = dsl_dir_space_available(dd->dd_parent, + NULL, 0, FALSE); + } else { + avail = dsl_pool_adjustedsize(dd->dd_pool, B_FALSE) - used; + } + + if (delta > 0 && delta > avail) + return (ENOSPC); + if (delta > 0 && dd->dd_phys->dd_quota > 0 && + new_reservation > dd->dd_phys->dd_quota) + return (ENOSPC); + return (0); +} + +static void +dsl_dir_set_reservation_sync(void *arg1, void *arg2, dmu_tx_t *tx) +{ + dsl_dir_t *dd = arg1; + uint64_t *reservationp = arg2; + uint64_t new_reservation = *reservationp; + uint64_t used; + int64_t delta; + + mutex_enter(&dd->dd_lock); + used = dd->dd_used_bytes; + delta = MAX(used, new_reservation) - + MAX(used, dd->dd_phys->dd_reserved); + mutex_exit(&dd->dd_lock); + + dmu_buf_will_dirty(dd->dd_dbuf, tx); + dd->dd_phys->dd_reserved = new_reservation; + + if (dd->dd_parent != NULL) { + /* Roll up this additional usage into our ancestors */ + dsl_dir_diduse_space(dd->dd_parent, delta, 0, 0, tx); + } +} + +int +dsl_dir_set_reservation(const char *ddname, uint64_t reservation) +{ + dsl_dir_t *dd; + int err; + + err = dsl_dir_open(ddname, FTAG, &dd, NULL); + if (err) + return (err); + err = dsl_sync_task_do(dd->dd_pool, dsl_dir_set_reservation_check, + dsl_dir_set_reservation_sync, dd, &reservation, 0); + dsl_dir_close(dd, FTAG); + return (err); +} + +static dsl_dir_t * +closest_common_ancestor(dsl_dir_t *ds1, dsl_dir_t *ds2) +{ + for (; ds1; ds1 = ds1->dd_parent) { + dsl_dir_t *dd; + for (dd = ds2; dd; dd = dd->dd_parent) { + if (ds1 == dd) + return (dd); + } + } + return (NULL); +} + +/* + * If delta is applied to dd, how much of that delta would be applied to + * ancestor? Syncing context only. + */ +static int64_t +would_change(dsl_dir_t *dd, int64_t delta, dsl_dir_t *ancestor) +{ + if (dd == ancestor) + return (delta); + + mutex_enter(&dd->dd_lock); + delta = parent_delta(dd, dd->dd_used_bytes, delta); + mutex_exit(&dd->dd_lock); + return (would_change(dd->dd_parent, delta, ancestor)); +} + +struct renamearg { + dsl_dir_t *newparent; + const char *mynewname; +}; + +/* ARGSUSED */ +static int +dsl_dir_rename_check(void *arg1, void *arg2, dmu_tx_t *tx) +{ + dsl_dir_t *dd = arg1; + struct renamearg *ra = arg2; + dsl_pool_t *dp = dd->dd_pool; + objset_t *mos = dp->dp_meta_objset; + int err; + uint64_t val; + + /* There should be 2 references: the open and the dirty */ + if (dmu_buf_refcount(dd->dd_dbuf) > 2) + return (EBUSY); + + /* check for existing name */ + err = zap_lookup(mos, ra->newparent->dd_phys->dd_child_dir_zapobj, + ra->mynewname, 8, 1, &val); + if (err == 0) + return (EEXIST); + if (err != ENOENT) + return (err); + + if (ra->newparent != dd->dd_parent) { + /* is there enough space? */ + uint64_t myspace = + MAX(dd->dd_used_bytes, dd->dd_phys->dd_reserved); + + /* no rename into our descendant */ + if (closest_common_ancestor(dd, ra->newparent) == dd) + return (EINVAL); + + if (err = dsl_dir_transfer_possible(dd->dd_parent, + ra->newparent, myspace)) + return (err); + } + + return (0); +} + +static void +dsl_dir_rename_sync(void *arg1, void *arg2, dmu_tx_t *tx) +{ + dsl_dir_t *dd = arg1; + struct renamearg *ra = arg2; + dsl_pool_t *dp = dd->dd_pool; + objset_t *mos = dp->dp_meta_objset; + int err; + + ASSERT(dmu_buf_refcount(dd->dd_dbuf) <= 2); + + if (ra->newparent != dd->dd_parent) { + uint64_t myspace = + MAX(dd->dd_used_bytes, dd->dd_phys->dd_reserved); + + dsl_dir_diduse_space(dd->dd_parent, -myspace, + -dd->dd_phys->dd_compressed_bytes, + -dd->dd_phys->dd_uncompressed_bytes, tx); + dsl_dir_diduse_space(ra->newparent, myspace, + dd->dd_phys->dd_compressed_bytes, + dd->dd_phys->dd_uncompressed_bytes, tx); + } + + dmu_buf_will_dirty(dd->dd_dbuf, tx); + + /* remove from old parent zapobj */ + err = zap_remove(mos, dd->dd_parent->dd_phys->dd_child_dir_zapobj, + dd->dd_myname, tx); + ASSERT3U(err, ==, 0); + + (void) strcpy(dd->dd_myname, ra->mynewname); + dsl_dir_close(dd->dd_parent, dd); + dd->dd_phys->dd_parent_obj = ra->newparent->dd_object; + VERIFY(0 == dsl_dir_open_obj(dd->dd_pool, + ra->newparent->dd_object, NULL, dd, &dd->dd_parent)); + + /* add to new parent zapobj */ + err = zap_add(mos, ra->newparent->dd_phys->dd_child_dir_zapobj, + dd->dd_myname, 8, 1, &dd->dd_object, tx); + ASSERT3U(err, ==, 0); +} + +int +dsl_dir_rename(dsl_dir_t *dd, const char *newname) +{ + struct renamearg ra; + int err; + + /* new parent should exist */ + err = dsl_dir_open(newname, FTAG, &ra.newparent, &ra.mynewname); + if (err) + return (err); + + /* can't rename to different pool */ + if (dd->dd_pool != ra.newparent->dd_pool) { + err = ENXIO; + goto out; + } + + /* new name should not already exist */ + if (ra.mynewname == NULL) { + err = EEXIST; + goto out; + } + + + err = dsl_sync_task_do(dd->dd_pool, + dsl_dir_rename_check, dsl_dir_rename_sync, dd, &ra, 3); + +out: + dsl_dir_close(ra.newparent, FTAG); + return (err); +} + +int +dsl_dir_transfer_possible(dsl_dir_t *sdd, dsl_dir_t *tdd, uint64_t space) +{ + dsl_dir_t *ancestor; + int64_t adelta; + uint64_t avail; + + ancestor = closest_common_ancestor(sdd, tdd); + adelta = would_change(sdd, -space, ancestor); + avail = dsl_dir_space_available(tdd, ancestor, adelta, FALSE); + if (avail < space) + return (ENOSPC); + + return (0); +} |