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Diffstat (limited to 'uts/common/fs/zfs/dsl_synctask.c')
-rw-r--r--uts/common/fs/zfs/dsl_synctask.c240
1 files changed, 240 insertions, 0 deletions
diff --git a/uts/common/fs/zfs/dsl_synctask.c b/uts/common/fs/zfs/dsl_synctask.c
new file mode 100644
index 000000000000..b0818ce274d4
--- /dev/null
+++ b/uts/common/fs/zfs/dsl_synctask.c
@@ -0,0 +1,240 @@
+/*
+ * 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_tx.h>
+#include <sys/dsl_pool.h>
+#include <sys/dsl_dir.h>
+#include <sys/dsl_synctask.h>
+#include <sys/metaslab.h>
+
+#define DST_AVG_BLKSHIFT 14
+
+/* ARGSUSED */
+static int
+dsl_null_checkfunc(void *arg1, void *arg2, dmu_tx_t *tx)
+{
+ return (0);
+}
+
+dsl_sync_task_group_t *
+dsl_sync_task_group_create(dsl_pool_t *dp)
+{
+ dsl_sync_task_group_t *dstg;
+
+ dstg = kmem_zalloc(sizeof (dsl_sync_task_group_t), KM_SLEEP);
+ list_create(&dstg->dstg_tasks, sizeof (dsl_sync_task_t),
+ offsetof(dsl_sync_task_t, dst_node));
+ dstg->dstg_pool = dp;
+
+ return (dstg);
+}
+
+void
+dsl_sync_task_create(dsl_sync_task_group_t *dstg,
+ dsl_checkfunc_t *checkfunc, dsl_syncfunc_t *syncfunc,
+ void *arg1, void *arg2, int blocks_modified)
+{
+ dsl_sync_task_t *dst;
+
+ if (checkfunc == NULL)
+ checkfunc = dsl_null_checkfunc;
+ dst = kmem_zalloc(sizeof (dsl_sync_task_t), KM_SLEEP);
+ dst->dst_checkfunc = checkfunc;
+ dst->dst_syncfunc = syncfunc;
+ dst->dst_arg1 = arg1;
+ dst->dst_arg2 = arg2;
+ list_insert_tail(&dstg->dstg_tasks, dst);
+
+ dstg->dstg_space += blocks_modified << DST_AVG_BLKSHIFT;
+}
+
+int
+dsl_sync_task_group_wait(dsl_sync_task_group_t *dstg)
+{
+ dmu_tx_t *tx;
+ uint64_t txg;
+ dsl_sync_task_t *dst;
+
+top:
+ tx = dmu_tx_create_dd(dstg->dstg_pool->dp_mos_dir);
+ VERIFY(0 == dmu_tx_assign(tx, TXG_WAIT));
+
+ txg = dmu_tx_get_txg(tx);
+
+ /* Do a preliminary error check. */
+ dstg->dstg_err = 0;
+ rw_enter(&dstg->dstg_pool->dp_config_rwlock, RW_READER);
+ for (dst = list_head(&dstg->dstg_tasks); dst;
+ dst = list_next(&dstg->dstg_tasks, dst)) {
+#ifdef ZFS_DEBUG
+ /*
+ * Only check half the time, otherwise, the sync-context
+ * check will almost never fail.
+ */
+ if (spa_get_random(2) == 0)
+ continue;
+#endif
+ dst->dst_err =
+ dst->dst_checkfunc(dst->dst_arg1, dst->dst_arg2, tx);
+ if (dst->dst_err)
+ dstg->dstg_err = dst->dst_err;
+ }
+ rw_exit(&dstg->dstg_pool->dp_config_rwlock);
+
+ if (dstg->dstg_err) {
+ dmu_tx_commit(tx);
+ return (dstg->dstg_err);
+ }
+
+ /*
+ * We don't generally have many sync tasks, so pay the price of
+ * add_tail to get the tasks executed in the right order.
+ */
+ VERIFY(0 == txg_list_add_tail(&dstg->dstg_pool->dp_sync_tasks,
+ dstg, txg));
+
+ dmu_tx_commit(tx);
+
+ txg_wait_synced(dstg->dstg_pool, txg);
+
+ if (dstg->dstg_err == EAGAIN) {
+ txg_wait_synced(dstg->dstg_pool, txg + TXG_DEFER_SIZE);
+ goto top;
+ }
+
+ return (dstg->dstg_err);
+}
+
+void
+dsl_sync_task_group_nowait(dsl_sync_task_group_t *dstg, dmu_tx_t *tx)
+{
+ uint64_t txg;
+
+ dstg->dstg_nowaiter = B_TRUE;
+ txg = dmu_tx_get_txg(tx);
+ /*
+ * We don't generally have many sync tasks, so pay the price of
+ * add_tail to get the tasks executed in the right order.
+ */
+ VERIFY(0 == txg_list_add_tail(&dstg->dstg_pool->dp_sync_tasks,
+ dstg, txg));
+}
+
+void
+dsl_sync_task_group_destroy(dsl_sync_task_group_t *dstg)
+{
+ dsl_sync_task_t *dst;
+
+ while (dst = list_head(&dstg->dstg_tasks)) {
+ list_remove(&dstg->dstg_tasks, dst);
+ kmem_free(dst, sizeof (dsl_sync_task_t));
+ }
+ kmem_free(dstg, sizeof (dsl_sync_task_group_t));
+}
+
+void
+dsl_sync_task_group_sync(dsl_sync_task_group_t *dstg, dmu_tx_t *tx)
+{
+ dsl_sync_task_t *dst;
+ dsl_pool_t *dp = dstg->dstg_pool;
+ uint64_t quota, used;
+
+ ASSERT3U(dstg->dstg_err, ==, 0);
+
+ /*
+ * Check for sufficient space. We just check against what's
+ * on-disk; we don't want any in-flight accounting to get in our
+ * way, because open context may have already used up various
+ * in-core limits (arc_tempreserve, dsl_pool_tempreserve).
+ */
+ quota = dsl_pool_adjustedsize(dp, B_FALSE) -
+ metaslab_class_get_deferred(spa_normal_class(dp->dp_spa));
+ used = dp->dp_root_dir->dd_phys->dd_used_bytes;
+ /* MOS space is triple-dittoed, so we multiply by 3. */
+ if (dstg->dstg_space > 0 && used + dstg->dstg_space * 3 > quota) {
+ dstg->dstg_err = ENOSPC;
+ return;
+ }
+
+ /*
+ * Check for errors by calling checkfuncs.
+ */
+ rw_enter(&dp->dp_config_rwlock, RW_WRITER);
+ for (dst = list_head(&dstg->dstg_tasks); dst;
+ dst = list_next(&dstg->dstg_tasks, dst)) {
+ dst->dst_err =
+ dst->dst_checkfunc(dst->dst_arg1, dst->dst_arg2, tx);
+ if (dst->dst_err)
+ dstg->dstg_err = dst->dst_err;
+ }
+
+ if (dstg->dstg_err == 0) {
+ /*
+ * Execute sync tasks.
+ */
+ for (dst = list_head(&dstg->dstg_tasks); dst;
+ dst = list_next(&dstg->dstg_tasks, dst)) {
+ dst->dst_syncfunc(dst->dst_arg1, dst->dst_arg2, tx);
+ }
+ }
+ rw_exit(&dp->dp_config_rwlock);
+
+ if (dstg->dstg_nowaiter)
+ dsl_sync_task_group_destroy(dstg);
+}
+
+int
+dsl_sync_task_do(dsl_pool_t *dp,
+ dsl_checkfunc_t *checkfunc, dsl_syncfunc_t *syncfunc,
+ void *arg1, void *arg2, int blocks_modified)
+{
+ dsl_sync_task_group_t *dstg;
+ int err;
+
+ ASSERT(spa_writeable(dp->dp_spa));
+
+ dstg = dsl_sync_task_group_create(dp);
+ dsl_sync_task_create(dstg, checkfunc, syncfunc,
+ arg1, arg2, blocks_modified);
+ err = dsl_sync_task_group_wait(dstg);
+ dsl_sync_task_group_destroy(dstg);
+ return (err);
+}
+
+void
+dsl_sync_task_do_nowait(dsl_pool_t *dp,
+ dsl_checkfunc_t *checkfunc, dsl_syncfunc_t *syncfunc,
+ void *arg1, void *arg2, int blocks_modified, dmu_tx_t *tx)
+{
+ dsl_sync_task_group_t *dstg;
+
+ if (!spa_writeable(dp->dp_spa))
+ return;
+
+ dstg = dsl_sync_task_group_create(dp);
+ dsl_sync_task_create(dstg, checkfunc, syncfunc,
+ arg1, arg2, blocks_modified);
+ dsl_sync_task_group_nowait(dstg, tx);
+}