X-Git-Url: https://git.camperquake.de/gitweb.cgi?a=blobdiff_plain;f=module%2Fzfs%2Fdsl_dir.c;h=377df40a8599cbb4c193a6f33a2c90dac5122cc0;hb=2ae10319624869eef0954cdfcdb6f5e33cba2e09;hp=2e52f9c732a6f470d7c2973843ff6db8ac2d47ab;hpb=c65aa5b2b9c48375ea1c451f252f0056e16f4e49;p=zfs.git

diff --git a/module/zfs/dsl_dir.c b/module/zfs/dsl_dir.c
index 2e52f9c..377df40 100644
--- a/module/zfs/dsl_dir.c
+++ b/module/zfs/dsl_dir.c
@@ -47,7 +47,7 @@ static void
 dsl_dir_evict(dmu_buf_t *db, void *arg)
 {
 	dsl_dir_t *dd = arg;
-	dsl_pool_t *dp = dd->dd_pool;
+	ASSERTV(dsl_pool_t *dp = dd->dd_pool;)
 	int t;
 
 	for (t = 0; t < TXG_SIZE; t++) {
@@ -96,7 +96,7 @@ dsl_dir_open_obj(dsl_pool_t *dp, uint64_t ddobj,
 	if (dd == NULL) {
 		dsl_dir_t *winner;
 
-		dd = kmem_zalloc(sizeof (dsl_dir_t), KM_SLEEP);
+		dd = kmem_zalloc(sizeof (dsl_dir_t), KM_PUSHPAGE);
 		dd->dd_object = ddobj;
 		dd->dd_dbuf = dbuf;
 		dd->dd_pool = dp;
@@ -303,7 +303,7 @@ int
 dsl_dir_open_spa(spa_t *spa, const char *name, void *tag,
     dsl_dir_t **ddp, const char **tailp)
 {
-	char buf[MAXNAMELEN];
+	char *buf;
 	const char *next, *nextnext = NULL;
 	int err;
 	dsl_dir_t *dd;
@@ -313,14 +313,15 @@ dsl_dir_open_spa(spa_t *spa, const char *name, void *tag,
 
 	dprintf("%s\n", name);
 
+	buf = kmem_alloc(MAXNAMELEN, KM_SLEEP);
 	err = getcomponent(name, buf, &next);
 	if (err)
-		return (err);
+		goto error;
 	if (spa == NULL) {
 		err = spa_open(buf, &spa, FTAG);
 		if (err) {
 			dprintf("spa_open(%s) failed\n", buf);
-			return (err);
+			goto error;
 		}
 		openedspa = TRUE;
 
@@ -336,7 +337,7 @@ dsl_dir_open_spa(spa_t *spa, const char *name, void *tag,
 		rw_exit(&dp->dp_config_rwlock);
 		if (openedspa)
 			spa_close(spa, FTAG);
-		return (err);
+		goto error;
 	}
 
 	while (next != NULL) {
@@ -372,7 +373,7 @@ dsl_dir_open_spa(spa_t *spa, const char *name, void *tag,
 		dsl_dir_close(dd, tag);
 		if (openedspa)
 			spa_close(spa, FTAG);
-		return (err);
+		goto error;
 	}
 
 	/*
@@ -391,6 +392,8 @@ dsl_dir_open_spa(spa_t *spa, const char *name, void *tag,
 	if (openedspa)
 		spa_close(spa, FTAG);
 	*ddp = dd;
+error:
+	kmem_free(buf, MAXNAMELEN);
 	return (err);
 }
 
@@ -457,12 +460,14 @@ dsl_dir_destroy_check(void *arg1, void *arg2, dmu_tx_t *tx)
 	/*
 	 * 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.
+	 * head ds.  If there are more holds, then a concurrent thread is
+	 * performing a lookup inside this dir while we're trying to destroy
+	 * it.  To minimize this possibility, we perform this check only
+	 * in syncing context and fail the operation if we encounter
+	 * additional holds.  The dp_config_rwlock ensures that nobody else
+	 * opens it after we check.
 	 */
-	if (dmu_buf_refcount(dd->dd_dbuf) > 2)
+	if (dmu_tx_is_syncing(tx) && dmu_buf_refcount(dd->dd_dbuf) > 2)
 		return (EBUSY);
 
 	err = zap_count(mos, dd->dd_phys->dd_child_dir_zapobj, &count);
@@ -788,7 +793,7 @@ dsl_dir_tempreserve_impl(dsl_dir_t *dd, uint64_t asize, boolean_t netfree,
 	    asize - ref_rsrv);
 	mutex_exit(&dd->dd_lock);
 
-	tr = kmem_zalloc(sizeof (struct tempreserve), KM_SLEEP);
+	tr = kmem_zalloc(sizeof (struct tempreserve), KM_PUSHPAGE);
 	tr->tr_ds = dd;
 	tr->tr_size = asize;
 	list_insert_tail(tr_list, tr);
@@ -822,7 +827,7 @@ dsl_dir_tempreserve_space(dsl_dir_t *dd, uint64_t lsize, uint64_t asize,
 		return (0);
 	}
 
-	tr_list = kmem_alloc(sizeof (list_t), KM_SLEEP);
+	tr_list = kmem_alloc(sizeof (list_t), KM_PUSHPAGE);
 	list_create(tr_list, sizeof (struct tempreserve),
 	    offsetof(struct tempreserve, tr_node));
 	ASSERT3S(asize, >, 0);
@@ -832,7 +837,7 @@ dsl_dir_tempreserve_space(dsl_dir_t *dd, uint64_t lsize, uint64_t asize,
 	if (err == 0) {
 		struct tempreserve *tr;
 
-		tr = kmem_zalloc(sizeof (struct tempreserve), KM_SLEEP);
+		tr = kmem_zalloc(sizeof (struct tempreserve), KM_PUSHPAGE);
 		tr->tr_size = lsize;
 		list_insert_tail(tr_list, tr);
 
@@ -848,7 +853,7 @@ dsl_dir_tempreserve_space(dsl_dir_t *dd, uint64_t lsize, uint64_t asize,
 	if (err == 0) {
 		struct tempreserve *tr;
 
-		tr = kmem_zalloc(sizeof (struct tempreserve), KM_SLEEP);
+		tr = kmem_zalloc(sizeof (struct tempreserve), KM_PUSHPAGE);
 		tr->tr_dp = dd->dd_pool;
 		tr->tr_size = asize;
 		list_insert_tail(tr_list, tr);
@@ -1061,10 +1066,6 @@ dsl_dir_set_quota_sync(void *arg1, void *arg2, dmu_tx_t *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
@@ -1177,10 +1178,6 @@ dsl_dir_set_reservation_sync(void *arg1, void *arg2, dmu_tx_t *tx)
 		    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
@@ -1416,3 +1413,10 @@ dsl_dir_snap_cmtime_update(dsl_dir_t *dd)
 	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