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freebsd-dev/module/zfs/dsl_dir.c
Richard Yao b8d06fca08 Switch KM_SLEEP to KM_PUSHPAGE 
Differences between how paging is done on Solaris and Linux can cause
deadlocks if KM_SLEEP is used in any the following contexts.

  * The txg_sync thread
  * The zvol write/discard threads
  * The zpl_putpage() VFS callback

This is because KM_SLEEP will allow for direct reclaim which may result
in the VM calling back in to the filesystem or block layer to write out
pages.  If a lock is held over this operation the potential exists to
deadlock the system.  To ensure forward progress all memory allocations
in these contexts must us KM_PUSHPAGE which disables performing any I/O
to accomplish the memory allocation.

Previously, this behavior was acheived by setting PF_MEMALLOC on the
thread.  However, that resulted in unexpected side effects such as the
exhaustion of pages in ZONE_DMA.  This approach touchs more of the zfs
code, but it is more consistent with the right way to handle these cases
under Linux.

This is patch lays the ground work for being able to safely revert the
following commits which used PF_MEMALLOC:

  21ade34 Disable direct reclaim for z_wr_* threads
  cfc9a5c Fix zpl_writepage() deadlock
  eec8164 Fix ASSERTION(!dsl_pool_sync_context(tx->tx_pool))

Signed-off-by: Richard Yao <ryao@cs.stonybrook.edu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #726
2012-08-27 12:01:37 -07:00

1429 lines
36 KiB
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/*
* 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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
*/
#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, dmu_tx_t *tx);
/* ARGSUSED */
static void
dsl_dir_evict(dmu_buf_t *db, void *arg)
{
dsl_dir_t *dd = arg;
ASSERTV(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 have been cleaned up by
* objset_evict().
*/
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_PUSHPAGE);
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));
}
if (dsl_dir_is_clone(dd)) {
dmu_buf_t *origin_bonus;
dsl_dataset_phys_t *origin_phys;
/*
* We can't open the origin dataset, because
* that would require opening this dsl_dir.
* Just look at its phys directly instead.
*/
err = dmu_bonus_hold(dp->dp_meta_objset,
dd->dd_phys->dd_origin_obj, FTAG, &origin_bonus);
if (err)
goto errout;
origin_phys = origin_bonus->db_data;
dd->dd_origin_txg =
origin_phys->ds_creation_txg;
dmu_buf_rele(origin_bonus, FTAG);
}
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;
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);
buf = kmem_alloc(MAXNAMELEN, KM_SLEEP);
err = getcomponent(name, buf, &next);
if (err)
goto error;
if (spa == NULL) {
err = spa_open(buf, &spa, FTAG);
if (err) {
dprintf("spa_open(%s) failed\n", buf);
goto error;
}
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);
goto error;
}
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);
goto error;
}
/*
* 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;
error:
kmem_free(buf, MAXNAMELEN);
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 *ddphys;
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);
ddphys = dbuf->db_data;
ddphys->dd_creation_time = gethrestime_sec();
if (pds)
ddphys->dd_parent_obj = pds->dd_object;
ddphys->dd_props_zapobj = zap_create(mos,
DMU_OT_DSL_PROPS, DMU_OT_NONE, 0, tx);
ddphys->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)
ddphys->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_dataset_t *ds = arg1;
dsl_dir_t *dd = ds->ds_dir;
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_dataset_t *ds = arg1;
dsl_dir_t *dd = ds->ds_dir;
objset_t *mos = dd->dd_pool->dp_meta_objset;
dsl_prop_setarg_t psa;
uint64_t value = 0;
uint64_t 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. */
dsl_prop_setarg_init_uint64(&psa, "reservation",
(ZPROP_SRC_NONE | ZPROP_SRC_LOCAL | ZPROP_SRC_RECEIVED),
&value);
psa.psa_effective_value = 0; /* predict default value */
dsl_dir_set_reservation_sync(ds, &psa, 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;
} 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_PUSHPAGE);
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_PUSHPAGE);
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_PUSHPAGE);
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_PUSHPAGE);
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_dataset_t *ds = arg1;
dsl_dir_t *dd = ds->ds_dir;
dsl_prop_setarg_t *psa = arg2;
int err;
uint64_t towrite;
if ((err = dsl_prop_predict_sync(ds->ds_dir, psa)) != 0)
return (err);
if (psa->psa_effective_value == 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) &&
(psa->psa_effective_value < dd->dd_phys->dd_reserved ||
psa->psa_effective_value < dd->dd_phys->dd_used_bytes + towrite)) {
err = ENOSPC;
}
mutex_exit(&dd->dd_lock);
return (err);
}
extern dsl_syncfunc_t dsl_prop_set_sync;
static void
dsl_dir_set_quota_sync(void *arg1, void *arg2, dmu_tx_t *tx)
{
dsl_dataset_t *ds = arg1;
dsl_dir_t *dd = ds->ds_dir;
dsl_prop_setarg_t *psa = arg2;
uint64_t effective_value = psa->psa_effective_value;
dsl_prop_set_sync(ds, psa, tx);
DSL_PROP_CHECK_PREDICTION(dd, psa);
dmu_buf_will_dirty(dd->dd_dbuf, tx);
mutex_enter(&dd->dd_lock);
dd->dd_phys->dd_quota = effective_value;
mutex_exit(&dd->dd_lock);
spa_history_log_internal(LOG_DS_QUOTA, dd->dd_pool->dp_spa,
tx, "%lld dataset = %llu ",
(longlong_t)effective_value, dd->dd_phys->dd_head_dataset_obj);
}
int
dsl_dir_set_quota(const char *ddname, zprop_source_t source, uint64_t quota)
{
dsl_dir_t *dd;
dsl_dataset_t *ds;
dsl_prop_setarg_t psa;
int err;
dsl_prop_setarg_init_uint64(&psa, "quota", source, &quota);
err = dsl_dataset_hold(ddname, FTAG, &ds);
if (err)
return (err);
err = dsl_dir_open(ddname, FTAG, &dd, NULL);
if (err) {
dsl_dataset_rele(ds, FTAG);
return (err);
}
ASSERT(ds->ds_dir == dd);
/*
* 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, ds, &psa, 0);
dsl_dir_close(dd, FTAG);
dsl_dataset_rele(ds, FTAG);
return (err);
}
int
dsl_dir_set_reservation_check(void *arg1, void *arg2, dmu_tx_t *tx)
{
dsl_dataset_t *ds = arg1;
dsl_dir_t *dd = ds->ds_dir;
dsl_prop_setarg_t *psa = arg2;
uint64_t effective_value;
uint64_t used, avail;
int err;
if ((err = dsl_prop_predict_sync(ds->ds_dir, psa)) != 0)
return (err);
effective_value = psa->psa_effective_value;
/*
* 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, effective_value) > MAX(used, dd->dd_phys->dd_reserved)) {
uint64_t delta = MAX(used, effective_value) -
MAX(used, dd->dd_phys->dd_reserved);
if (delta > avail)
return (ENOSPC);
if (dd->dd_phys->dd_quota > 0 &&
effective_value > 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_dataset_t *ds = arg1;
dsl_dir_t *dd = ds->ds_dir;
dsl_prop_setarg_t *psa = arg2;
uint64_t effective_value = psa->psa_effective_value;
uint64_t used;
int64_t delta;
dsl_prop_set_sync(ds, psa, tx);
DSL_PROP_CHECK_PREDICTION(dd, psa);
dmu_buf_will_dirty(dd->dd_dbuf, tx);
mutex_enter(&dd->dd_lock);
used = dd->dd_phys->dd_used_bytes;
delta = MAX(used, effective_value) -
MAX(used, dd->dd_phys->dd_reserved);
dd->dd_phys->dd_reserved = effective_value;
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_log_internal(LOG_DS_RESERVATION, dd->dd_pool->dp_spa,
tx, "%lld dataset = %llu",
(longlong_t)effective_value, dd->dd_phys->dd_head_dataset_obj);
}
int
dsl_dir_set_reservation(const char *ddname, zprop_source_t source,
uint64_t reservation)
{
dsl_dir_t *dd;
dsl_dataset_t *ds;
dsl_prop_setarg_t psa;
int err;
dsl_prop_setarg_init_uint64(&psa, "reservation", source, &reservation);
err = dsl_dataset_hold(ddname, FTAG, &ds);
if (err)
return (err);
err = dsl_dir_open(ddname, FTAG, &dd, NULL);
if (err) {
dsl_dataset_rele(ds, FTAG);
return (err);
}
ASSERT(ds->ds_dir == dd);
err = dsl_sync_task_do(dd->dd_pool, dsl_dir_set_reservation_check,
dsl_dir_set_reservation_sync, ds, &psa, 0);
dsl_dir_close(dd, FTAG);
dsl_dataset_rele(ds, 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;
};
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 only be one reference, from dmu_objset_rename().
* Fleeting holds are also possible (eg, from "zfs list" getting
* stats), but any that are present in open context will likely
* be gone by syncing context, so only fail from syncing
* context.
*/
if (dmu_tx_is_syncing(tx) && dmu_buf_refcount(dd->dd_dbuf) > 1)
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, 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_log_internal(LOG_DS_RENAME, dd->dd_pool->dp_spa,
tx, "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);
}
#if defined(_KERNEL) && defined(HAVE_SPL)
EXPORT_SYMBOL(dsl_dir_set_quota);
EXPORT_SYMBOL(dsl_dir_set_reservation);
EXPORT_SYMBOL(dsl_dir_open);
EXPORT_SYMBOL(dsl_dir_close);
#endif
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