dsl_dir.c revision a15215608b8bd90f714f6db21ee623b584607cb6
/*
* 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 2009 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#include <sys/dmu.h>
#include <sys/dmu_objset.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/dsl_deleg.h>
#include <sys/spa.h>
#include <sys/metaslab.h>
#include <sys/zap.h>
#include <sys/zio.h>
#include <sys/arc.h>
#include <sys/sunddi.h>
#include "zfs_namecheck.h"
static uint64_t dsl_dir_space_towrite(dsl_dir_t *dd);
static void dsl_dir_set_reservation_sync(void *arg1, void *arg2,
cred_t *cr, 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);
}
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);
ASSERT3U(doi.doi_bonus_size, >=, sizeof (dsl_dir_phys_t));
}
#endif
if (dd == NULL) {
dsl_dir_t *winner;
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;
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));
dsl_dir_snap_cmtime_update(dd);
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)
goto errout;
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, 0, dd->dd_myname);
}
if (err)
goto errout;
} 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);
errout:
if (dd->dd_parent)
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);
}
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);
}
static int
getcomponent(const char *path, char *component, const char **nextp)
{
char *p;
if ((path == NULL) || (path[0] == '\0'))
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_pool_t *dp, dsl_dir_t *pds, const char *name,
dmu_tx_t *tx)
{
objset_t *mos = dp->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);
if (pds) {
VERIFY(0 == zap_add(mos, pds->dd_phys->dd_child_dir_zapobj,
name, sizeof (uint64_t), 1, &ddobj, tx));
} else {
/* it's the root dir */
VERIFY(0 == zap_add(mos, DMU_POOL_DIRECTORY_OBJECT,
DMU_POOL_ROOT_DATASET, 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();
if (pds)
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);
if (spa_version(dp->dp_spa) >= SPA_VERSION_USED_BREAKDOWN)
dsphys->dd_flags |= DD_FLAG_USED_BREAKDOWN;
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, cred_t *cr, dmu_tx_t *tx)
{
dsl_dir_t *dd = arg1;
objset_t *mos = dd->dd_pool->dp_meta_objset;
uint64_t val, obj;
dd_used_t t;
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, cr, tx);
ASSERT3U(dd->dd_phys->dd_used_bytes, ==, 0);
ASSERT3U(dd->dd_phys->dd_reserved, ==, 0);
for (t = 0; t < DD_USED_NUM; t++)
ASSERT3U(dd->dd_phys->dd_used_breakdown[t], ==, 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 == dsl_deleg_destroy(mos, dd->dd_phys->dd_deleg_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));
}
boolean_t
dsl_dir_is_clone(dsl_dir_t *dd)
{
return (dd->dd_phys->dd_origin_obj &&
(dd->dd_pool->dp_origin_snap == NULL ||
dd->dd_phys->dd_origin_obj !=
dd->dd_pool->dp_origin_snap->ds_object));
}
void
dsl_dir_stats(dsl_dir_t *dd, nvlist_t *nv)
{
mutex_enter(&dd->dd_lock);
dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED,
dd->dd_phys->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));
if (dd->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) {
dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USEDSNAP,
dd->dd_phys->dd_used_breakdown[DD_USED_SNAP]);
dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USEDDS,
dd->dd_phys->dd_used_breakdown[DD_USED_HEAD]);
dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USEDREFRESERV,
dd->dd_phys->dd_used_breakdown[DD_USED_REFRSRV]);
dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USEDCHILD,
dd->dd_phys->dd_used_breakdown[DD_USED_CHILD] +
dd->dd_phys->dd_used_breakdown[DD_USED_CHILD_RSRV]);
}
mutex_exit(&dd->dd_lock);
rw_enter(&dd->dd_pool->dp_config_rwlock, RW_READER);
if (dsl_dir_is_clone(dd)) {
dsl_dataset_t *ds;
char buf[MAXNAMELEN];
VERIFY(0 == dsl_dataset_hold_obj(dd->dd_pool,
dd->dd_phys->dd_origin_obj, FTAG, &ds));
dsl_dataset_name(ds, buf);
dsl_dataset_rele(ds, FTAG);
dsl_prop_nvlist_add_string(nv, ZFS_PROP_ORIGIN, buf);
}
rw_exit(&dd->dd_pool->dp_config_rwlock);
}
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;
mutex_exit(&dd->dd_lock);
/* release the hold from dsl_dir_dirty */
dmu_buf_rele(dd->dd_dbuf, dd);
}
static uint64_t
dsl_dir_space_towrite(dsl_dir_t *dd)
{
uint64_t space = 0;
int i;
ASSERT(MUTEX_HELD(&dd->dd_lock));
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;
used = dd->dd_phys->dd_used_bytes;
if (!ondiskonly)
used += dsl_dir_space_towrite(dd);
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 (dd == ancestor) {
ASSERT(delta <= 0);
ASSERT(used >= -delta);
used += delta;
if (parentspace != UINT64_MAX)
parentspace -= delta;
}
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_dspace(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_pool_t *tr_dp;
dsl_dir_t *tr_ds;
uint64_t tr_size;
};
static int
dsl_dir_tempreserve_impl(dsl_dir_t *dd, uint64_t asize, boolean_t netfree,
boolean_t ignorequota, boolean_t checkrefquota, list_t *tr_list,
dmu_tx_t *tx, boolean_t first)
{
uint64_t txg = tx->tx_txg;
uint64_t est_inflight, used_on_disk, quota, parent_rsrv;
uint64_t deferred = 0;
struct tempreserve *tr;
int retval = EDQUOT;
int txgidx = txg & TXG_MASK;
int i;
uint64_t ref_rsrv = 0;
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_inflight = dsl_dir_space_towrite(dd);
for (i = 0; i < TXG_SIZE; i++)
est_inflight += dd->dd_tempreserved[i];
used_on_disk = dd->dd_phys->dd_used_bytes;
/*
* On the first iteration, fetch the dataset's used-on-disk and
* refreservation values. Also, if checkrefquota is set, test if
* allocating this space would exceed the dataset's refquota.
*/
if (first && tx->tx_objset) {
int error;
dsl_dataset_t *ds = tx->tx_objset->os_dsl_dataset;
error = dsl_dataset_check_quota(ds, checkrefquota,
asize, est_inflight, &used_on_disk, &ref_rsrv);
if (error) {
mutex_exit(&dd->dd_lock);
return (error);
}
}
/*
* If this transaction will result in a net free of space,
* we want to let it through.
*/
if (ignorequota || netfree || dd->dd_phys->dd_quota == 0)
quota = UINT64_MAX;
else
quota = dd->dd_phys->dd_quota;
/*
* Adjust the quota against the actual pool size at the root
* minus any outstanding deferred frees.
* 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) {
spa_t *spa = dd->dd_pool->dp_spa;
uint64_t poolsize = dsl_pool_adjustedsize(dd->dd_pool, netfree);
deferred = metaslab_class_get_deferred(spa_normal_class(spa));
if (poolsize - deferred < quota) {
quota = poolsize - deferred;
retval = ENOSPC;
}
}
/*
* 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 (used_on_disk + est_inflight >= quota) {
if (est_inflight > 0 || used_on_disk < quota ||
(retval == ENOSPC && used_on_disk < quota + deferred))
retval = ERESTART;
dprintf_dd(dd, "failing: used=%lluK inflight = %lluK "
"quota=%lluK tr=%lluK err=%d\n",
used_on_disk>>10, est_inflight>>10,
quota>>10, asize>>10, retval);
mutex_exit(&dd->dd_lock);
return (retval);
}
/* We need to up our estimated delta before dropping dd_lock */
dd->dd_tempreserved[txgidx] += asize;
parent_rsrv = parent_delta(dd, used_on_disk + est_inflight,
asize - ref_rsrv);
mutex_exit(&dd->dd_lock);
tr = kmem_zalloc(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) {
boolean_t ismos = (dd->dd_phys->dd_head_dataset_obj == 0);
return (dsl_dir_tempreserve_impl(dd->dd_parent,
parent_rsrv, netfree, ismos, TRUE, tr_list, tx, FALSE));
} else {
return (0);
}
}
/*
* Reserve space in this dsl_dir, to be used in this tx's txg.
* After the space has been dirtied (and 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, uint64_t usize, void **tr_cookiep, dmu_tx_t *tx)
{
int err;
list_t *tr_list;
if (asize == 0) {
*tr_cookiep = NULL;
return (0);
}
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 = arc_tempreserve_space(lsize, tx->tx_txg);
if (err == 0) {
struct tempreserve *tr;
tr = kmem_zalloc(sizeof (struct tempreserve), KM_SLEEP);
tr->tr_size = lsize;
list_insert_tail(tr_list, tr);
err = dsl_pool_tempreserve_space(dd->dd_pool, asize, tx);
} else {
if (err == EAGAIN) {
txg_delay(dd->dd_pool, tx->tx_txg, 1);
err = ERESTART;
}
dsl_pool_memory_pressure(dd->dd_pool);
}
if (err == 0) {
struct tempreserve *tr;
tr = kmem_zalloc(sizeof (struct tempreserve), KM_SLEEP);
tr->tr_dp = dd->dd_pool;
tr->tr_size = asize;
list_insert_tail(tr_list, tr);
err = dsl_dir_tempreserve_impl(dd, asize, fsize >= asize,
FALSE, asize > usize, tr_list, tx, TRUE);
}
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);
if (tr_cookie == NULL)
return;
while (tr = list_head(tr_list)) {
if (tr->tr_dp) {
dsl_pool_tempreserve_clear(tr->tr_dp, tr->tr_size, tx);
} else if (tr->tr_ds) {
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);
} else {
arc_tempreserve_clear(tr->tr_size);
}
list_remove(tr_list, tr);
kmem_free(tr, sizeof (struct tempreserve));
}
kmem_free(tr_list, sizeof (list_t));
}
static void
dsl_dir_willuse_space_impl(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_space_towrite(dd) + dd->dd_phys->dd_used_bytes;
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_impl(dd->dd_parent, parent_space, tx);
}
/*
* 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)
{
dsl_pool_willuse_space(dd->dd_pool, space, tx);
dsl_dir_willuse_space_impl(dd, space, tx);
}
/* call from syncing context when we actually write/free space for this dd */
void
dsl_dir_diduse_space(dsl_dir_t *dd, dd_used_t type,
int64_t used, int64_t compressed, int64_t uncompressed, dmu_tx_t *tx)
{
int64_t accounted_delta;
boolean_t needlock = !MUTEX_HELD(&dd->dd_lock);
ASSERT(dmu_tx_is_syncing(tx));
ASSERT(type < DD_USED_NUM);
dsl_dir_dirty(dd, tx);
if (needlock)
mutex_enter(&dd->dd_lock);
accounted_delta = parent_delta(dd, dd->dd_phys->dd_used_bytes, used);
ASSERT(used >= 0 || dd->dd_phys->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_phys->dd_used_bytes += used;
dd->dd_phys->dd_uncompressed_bytes += uncompressed;
dd->dd_phys->dd_compressed_bytes += compressed;
if (dd->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) {
ASSERT(used > 0 ||
dd->dd_phys->dd_used_breakdown[type] >= -used);
dd->dd_phys->dd_used_breakdown[type] += used;
#ifdef DEBUG
dd_used_t t;
uint64_t u = 0;
for (t = 0; t < DD_USED_NUM; t++)
u += dd->dd_phys->dd_used_breakdown[t];
ASSERT3U(u, ==, dd->dd_phys->dd_used_bytes);
#endif
}
if (needlock)
mutex_exit(&dd->dd_lock);
if (dd->dd_parent != NULL) {
dsl_dir_diduse_space(dd->dd_parent, DD_USED_CHILD,
accounted_delta, compressed, uncompressed, tx);
dsl_dir_transfer_space(dd->dd_parent,
used - accounted_delta,
DD_USED_CHILD_RSRV, DD_USED_CHILD, tx);
}
}
void
dsl_dir_transfer_space(dsl_dir_t *dd, int64_t delta,
dd_used_t oldtype, dd_used_t newtype, dmu_tx_t *tx)
{
boolean_t needlock = !MUTEX_HELD(&dd->dd_lock);
ASSERT(dmu_tx_is_syncing(tx));
ASSERT(oldtype < DD_USED_NUM);
ASSERT(newtype < DD_USED_NUM);
if (delta == 0 || !(dd->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN))
return;
dsl_dir_dirty(dd, tx);
if (needlock)
mutex_enter(&dd->dd_lock);
ASSERT(delta > 0 ?
dd->dd_phys->dd_used_breakdown[oldtype] >= delta :
dd->dd_phys->dd_used_breakdown[newtype] >= -delta);
ASSERT(dd->dd_phys->dd_used_bytes >= ABS(delta));
dd->dd_phys->dd_used_breakdown[oldtype] -= delta;
dd->dd_phys->dd_used_breakdown[newtype] += delta;
if (needlock)
mutex_exit(&dd->dd_lock);
}
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-estimate the amount of space to be
* freed up.
*/
towrite = dsl_dir_space_towrite(dd);
if ((dmu_tx_is_syncing(tx) || towrite == 0) &&
(new_quota < dd->dd_phys->dd_reserved ||
new_quota < dd->dd_phys->dd_used_bytes + towrite)) {
err = ENOSPC;
}
mutex_exit(&dd->dd_lock);
return (err);
}
/* ARGSUSED */
static void
dsl_dir_set_quota_sync(void *arg1, void *arg2, cred_t *cr, 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);
spa_history_internal_log(LOG_DS_QUOTA, dd->dd_pool->dp_spa,
tx, cr, "%lld dataset = %llu ",
(longlong_t)new_quota, dd->dd_phys->dd_head_dataset_obj);
}
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 (quota != dd->dd_phys->dd_quota) {
/*
* 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, &quota, 0);
}
dsl_dir_close(dd, FTAG);
return (err);
}
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;
/*
* 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_phys->dd_used_bytes;
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 (MAX(used, new_reservation) > MAX(used, dd->dd_phys->dd_reserved)) {
uint64_t delta = MAX(used, new_reservation) -
MAX(used, dd->dd_phys->dd_reserved);
if (delta > avail)
return (ENOSPC);
if (dd->dd_phys->dd_quota > 0 &&
new_reservation > dd->dd_phys->dd_quota)
return (ENOSPC);
}
return (0);
}
/* ARGSUSED */
static void
dsl_dir_set_reservation_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx)
{
dsl_dir_t *dd = arg1;
uint64_t *reservationp = arg2;
uint64_t new_reservation = *reservationp;
uint64_t used;
int64_t delta;
dmu_buf_will_dirty(dd->dd_dbuf, tx);
mutex_enter(&dd->dd_lock);
used = dd->dd_phys->dd_used_bytes;
delta = MAX(used, new_reservation) -
MAX(used, dd->dd_phys->dd_reserved);
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, DD_USED_CHILD_RSRV,
delta, 0, 0, tx);
}
mutex_exit(&dd->dd_lock);
spa_history_internal_log(LOG_DS_RESERVATION, dd->dd_pool->dp_spa,
tx, cr, "%lld dataset = %llu",
(longlong_t)new_reservation, dd->dd_phys->dd_head_dataset_obj);
}
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_phys->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_phys->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, cred_t *cr, 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) {
dsl_dir_diduse_space(dd->dd_parent, DD_USED_CHILD,
-dd->dd_phys->dd_used_bytes,
-dd->dd_phys->dd_compressed_bytes,
-dd->dd_phys->dd_uncompressed_bytes, tx);
dsl_dir_diduse_space(ra->newparent, DD_USED_CHILD,
dd->dd_phys->dd_used_bytes,
dd->dd_phys->dd_compressed_bytes,
dd->dd_phys->dd_uncompressed_bytes, tx);
if (dd->dd_phys->dd_reserved > dd->dd_phys->dd_used_bytes) {
uint64_t unused_rsrv = dd->dd_phys->dd_reserved -
dd->dd_phys->dd_used_bytes;
dsl_dir_diduse_space(dd->dd_parent, DD_USED_CHILD_RSRV,
-unused_rsrv, 0, 0, tx);
dsl_dir_diduse_space(ra->newparent, DD_USED_CHILD_RSRV,
unused_rsrv, 0, 0, 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);
spa_history_internal_log(LOG_DS_RENAME, dd->dd_pool->dp_spa,
tx, cr, "dataset = %llu", dd->dd_phys->dd_head_dataset_obj);
}
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);
}
timestruc_t
dsl_dir_snap_cmtime(dsl_dir_t *dd)
{
timestruc_t t;
mutex_enter(&dd->dd_lock);
t = dd->dd_snap_cmtime;
mutex_exit(&dd->dd_lock);
return (t);
}
void
dsl_dir_snap_cmtime_update(dsl_dir_t *dd)
{
timestruc_t t;
gethrestime(&t);
mutex_enter(&dd->dd_lock);
dd->dd_snap_cmtime = t;
mutex_exit(&dd->dd_lock);
}