nowait synctask must succeed

If a `zfs_space_check_t` other than `ZFS_SPACE_CHECK_NONE` is used with
`dsl_sync_task_nowait()`, the sync task may fail due to ENOSPC.
However, there is no way to notice or communicate this failure, so it's
extremely difficult to use this functionality correctly, and in fact
almost all callers use `ZFS_SPACE_CHECK_NONE`.

This commit removes the `zfs_space_check_t` argument from
`dsl_sync_task_nowait()`, and always uses `ZFS_SPACE_CHECK_NONE`.

Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: Matthew Ahrens <[email protected]>
Closes #10855

9 files changed, 24 insertions, 39 deletions

diff --git a/module/zfs/dmu_redact.c b/module/zfs/dmu_redact.c
index df10d8d6f..1c5f1bd24 100644
--- a/module/zfs/dmu_redact.c
+++ b/module/zfs/dmu_redact.c
@@ -568,8 +568,7 @@ commit_rl_updates(objset_t *os, struct merge_data *md, uint64_t object,
 	uint64_t txg = dmu_tx_get_txg(tx);
 	if (!md->md_synctask_txg[txg & TXG_MASK]) {
 		dsl_sync_task_nowait(dmu_tx_pool(tx),
-		    redaction_list_update_sync, md, 5, ZFS_SPACE_CHECK_NONE,
-		    tx);
+		    redaction_list_update_sync, md, tx);
 		md->md_synctask_txg[txg & TXG_MASK] = B_TRUE;
 		md->md_latest_synctask_txg = txg;
 	}
diff --git a/module/zfs/dsl_synctask.c b/module/zfs/dsl_synctask.c
index 2d6ca8549..148e8fff2 100644
--- a/module/zfs/dsl_synctask.c
+++ b/module/zfs/dsl_synctask.c
@@ -170,15 +170,13 @@ dsl_sync_task_sig(const char *pool, dsl_checkfunc_t *checkfunc,
 
 static void
 dsl_sync_task_nowait_common(dsl_pool_t *dp, dsl_syncfunc_t *syncfunc, void *arg,
-    int blocks_modified, zfs_space_check_t space_check, dmu_tx_t *tx,
-    boolean_t early)
+    dmu_tx_t *tx, boolean_t early)
 {
 	dsl_sync_task_t *dst = kmem_zalloc(sizeof (*dst), KM_SLEEP);
 
 	dst->dst_pool = dp;
 	dst->dst_txg = dmu_tx_get_txg(tx);
-	dst->dst_space = blocks_modified << DST_AVG_BLKSHIFT;
-	dst->dst_space_check = space_check;
+	dst->dst_space_check = ZFS_SPACE_CHECK_NONE;
 	dst->dst_checkfunc = dsl_null_checkfunc;
 	dst->dst_syncfunc = syncfunc;
 	dst->dst_arg = arg;
@@ -192,18 +190,16 @@ dsl_sync_task_nowait_common(dsl_pool_t *dp, dsl_syncfunc_t *syncfunc, void *arg,
 
 void
 dsl_sync_task_nowait(dsl_pool_t *dp, dsl_syncfunc_t *syncfunc, void *arg,
-    int blocks_modified, zfs_space_check_t space_check, dmu_tx_t *tx)
+    dmu_tx_t *tx)
 {
-	dsl_sync_task_nowait_common(dp, syncfunc, arg,
-	    blocks_modified, space_check, tx, B_FALSE);
+	dsl_sync_task_nowait_common(dp, syncfunc, arg, tx, B_FALSE);
 }
 
 void
 dsl_early_sync_task_nowait(dsl_pool_t *dp, dsl_syncfunc_t *syncfunc, void *arg,
-    int blocks_modified, zfs_space_check_t space_check, dmu_tx_t *tx)
+    dmu_tx_t *tx)
 {
-	dsl_sync_task_nowait_common(dp, syncfunc, arg,
-	    blocks_modified, space_check, tx, B_TRUE);
+	dsl_sync_task_nowait_common(dp, syncfunc, arg, tx, B_TRUE);
 }
 
 /*
diff --git a/module/zfs/spa.c b/module/zfs/spa.c
index aac469f44..31fa52d1d 100644
--- a/module/zfs/spa.c
+++ b/module/zfs/spa.c
@@ -2688,8 +2688,7 @@ spa_livelist_condense_cb(void *arg, zthr_t *t)
 			lca->first_size = first_size;
 			lca->next_size = next_size;
 			dsl_sync_task_nowait(spa_get_dsl(spa),
-			    spa_livelist_condense_sync, lca, 0,
-			    ZFS_SPACE_CHECK_NONE, tx);
+			    spa_livelist_condense_sync, lca, tx);
 			dmu_tx_commit(tx);
 			return;
 		}
diff --git a/module/zfs/spa_history.c b/module/zfs/spa_history.c
index f47adb94d..2ab588154 100644
--- a/module/zfs/spa_history.c
+++ b/module/zfs/spa_history.c
@@ -397,8 +397,7 @@ spa_history_log_nvl(spa_t *spa, nvlist_t *nvl)
 	fnvlist_add_uint64(nvarg, ZPOOL_HIST_WHO, crgetruid(CRED()));
 
 	/* Kick this off asynchronously; errors are ignored. */
-	dsl_sync_task_nowait(spa_get_dsl(spa), spa_history_log_sync,
-	    nvarg, 0, ZFS_SPACE_CHECK_NONE, tx);
+	dsl_sync_task_nowait(spa_get_dsl(spa), spa_history_log_sync, nvarg, tx);
 	dmu_tx_commit(tx);
 
 	/* spa_history_log_sync will free nvl */
@@ -532,7 +531,7 @@ log_internal(nvlist_t *nvl, const char *operation, spa_t *spa,
 		spa_history_log_sync(nvl, tx);
 	} else {
 		dsl_sync_task_nowait(spa_get_dsl(spa),
-		    spa_history_log_sync, nvl, 0, ZFS_SPACE_CHECK_NONE, tx);
+		    spa_history_log_sync, nvl, tx);
 	}
 	/* spa_history_log_sync() will free nvl */
 }
diff --git a/module/zfs/vdev_indirect.c b/module/zfs/vdev_indirect.c
index 6bc2d917d..5301e0665 100644
--- a/module/zfs/vdev_indirect.c
+++ b/module/zfs/vdev_indirect.c
@@ -576,8 +576,7 @@ spa_condense_indirect_commit_entry(spa_t *spa,
 	 */
 	if (list_is_empty(&sci->sci_new_mapping_entries[txgoff])) {
 		dsl_sync_task_nowait(dmu_tx_pool(tx),
-		    spa_condense_indirect_commit_sync, sci,
-		    0, ZFS_SPACE_CHECK_NONE, tx);
+		    spa_condense_indirect_commit_sync, sci, tx);
 	}
 
 	vdev_indirect_mapping_entry_t *vime =
diff --git a/module/zfs/vdev_initialize.c b/module/zfs/vdev_initialize.c
index ab711441d..7ff7fffcc 100644
--- a/module/zfs/vdev_initialize.c
+++ b/module/zfs/vdev_initialize.c
@@ -126,7 +126,7 @@ vdev_initialize_change_state(vdev_t *vd, vdev_initializing_state_t new_state)
 	dmu_tx_t *tx = dmu_tx_create_dd(spa_get_dsl(spa)->dp_mos_dir);
 	VERIFY0(dmu_tx_assign(tx, TXG_WAIT));
 	dsl_sync_task_nowait(spa_get_dsl(spa), vdev_initialize_zap_update_sync,
-	    guid, 2, ZFS_SPACE_CHECK_NONE, tx);
+	    guid, tx);
 
 	switch (new_state) {
 	case VDEV_INITIALIZE_ACTIVE:
@@ -216,8 +216,7 @@ vdev_initialize_write(vdev_t *vd, uint64_t start, uint64_t size, abd_t *data)
 
 		/* This is the first write of this txg. */
 		dsl_sync_task_nowait(spa_get_dsl(spa),
-		    vdev_initialize_zap_update_sync, guid, 2,
-		    ZFS_SPACE_CHECK_RESERVED, tx);
+		    vdev_initialize_zap_update_sync, guid, tx);
 	}
 
 	/*
diff --git a/module/zfs/vdev_rebuild.c b/module/zfs/vdev_rebuild.c
index 85ed8afe1..3362d608c 100644
--- a/module/zfs/vdev_rebuild.c
+++ b/module/zfs/vdev_rebuild.c
@@ -267,7 +267,7 @@ vdev_rebuild_initiate(vdev_t *vd)
 	vd->vdev_rebuilding = B_TRUE;
 
 	dsl_sync_task_nowait(spa_get_dsl(spa), vdev_rebuild_initiate_sync,
-	    (void *)(uintptr_t)vd->vdev_id, 0, ZFS_SPACE_CHECK_NONE, tx);
+	    (void *)(uintptr_t)vd->vdev_id, tx);
 	dmu_tx_commit(tx);
 
 	vdev_rebuild_log_notify(spa, vd, ESC_ZFS_RESILVER_START);
@@ -553,8 +553,7 @@ vdev_rebuild_range(vdev_rebuild_t *vr, uint64_t start, uint64_t size)
 		vr->vr_scan_offset[txg & TXG_MASK] = start;
 		dsl_sync_task_nowait(spa_get_dsl(spa),
 		    vdev_rebuild_update_sync,
-		    (void *)(uintptr_t)vd->vdev_id, 2,
-		    ZFS_SPACE_CHECK_RESERVED, tx);
+		    (void *)(uintptr_t)vd->vdev_id, tx);
 	}
 
 	/* When exiting write out our progress. */
@@ -875,16 +874,14 @@ vdev_rebuild_thread(void *arg)
 		 * by a pool checkpoint.  See the dsl_scan_done() comments.
 		 */
 		dsl_sync_task_nowait(dp, vdev_rebuild_complete_sync,
-		    (void *)(uintptr_t)vd->vdev_id, 0,
-		    ZFS_SPACE_CHECK_NONE, tx);
+		    (void *)(uintptr_t)vd->vdev_id, tx);
 	} else if (vd->vdev_rebuild_cancel_wanted) {
 		/*
 		 * The rebuild operation was canceled.  This will occur when
 		 * a device participating in the rebuild is detached.
 		 */
 		dsl_sync_task_nowait(dp, vdev_rebuild_cancel_sync,
-		    (void *)(uintptr_t)vd->vdev_id, 0,
-		    ZFS_SPACE_CHECK_NONE, tx);
+		    (void *)(uintptr_t)vd->vdev_id, tx);
 	} else if (vd->vdev_rebuild_reset_wanted) {
 		/*
 		 * Reset the running rebuild without canceling and restarting
@@ -892,8 +889,7 @@ vdev_rebuild_thread(void *arg)
 		 * participate in the rebuild.
 		 */
 		dsl_sync_task_nowait(dp, vdev_rebuild_reset_sync,
-		    (void *)(uintptr_t)vd->vdev_id, 0,
-		    ZFS_SPACE_CHECK_NONE, tx);
+		    (void *)(uintptr_t)vd->vdev_id, tx);
 	} else {
 		/*
 		 * The rebuild operation should be suspended.  This may occur
diff --git a/module/zfs/vdev_removal.c b/module/zfs/vdev_removal.c
index 56e420871..fdeca7ab3 100644
--- a/module/zfs/vdev_removal.c
+++ b/module/zfs/vdev_removal.c
@@ -1167,8 +1167,8 @@ vdev_remove_replace_with_indirect(vdev_t *vd, uint64_t txg)
 
 	/* After this, we can not use svr. */
 	tx = dmu_tx_create_assigned(spa->spa_dsl_pool, txg);
-	dsl_sync_task_nowait(spa->spa_dsl_pool, vdev_remove_complete_sync, svr,
-	    0, ZFS_SPACE_CHECK_NONE, tx);
+	dsl_sync_task_nowait(spa->spa_dsl_pool,
+	    vdev_remove_complete_sync, svr, tx);
 	dmu_tx_commit(tx);
 }
 
@@ -1317,7 +1317,7 @@ spa_vdev_copy_impl(vdev_t *vd, spa_vdev_removal_t *svr, vdev_copy_arg_t *vca,
 
 	if (svr->svr_max_offset_to_sync[txg & TXG_MASK] == 0) {
 		dsl_sync_task_nowait(dmu_tx_pool(tx), vdev_mapping_sync,
-		    svr, 0, ZFS_SPACE_CHECK_NONE, tx);
+		    svr, tx);
 	}
 
 	svr->svr_max_offset_to_sync[txg & TXG_MASK] = range_tree_max(segs);
@@ -2143,8 +2143,7 @@ spa_vdev_remove_top(vdev_t *vd, uint64_t *txg)
 	vdev_config_dirty(vd);
 	dmu_tx_t *tx = dmu_tx_create_assigned(spa->spa_dsl_pool, *txg);
 	dsl_sync_task_nowait(spa->spa_dsl_pool,
-	    vdev_remove_initiate_sync,
-	    (void *)(uintptr_t)vd->vdev_id, 0, ZFS_SPACE_CHECK_NONE, tx);
+	    vdev_remove_initiate_sync, (void *)(uintptr_t)vd->vdev_id, tx);
 	dmu_tx_commit(tx);
 
 	return (0);
diff --git a/module/zfs/vdev_trim.c b/module/zfs/vdev_trim.c
index 7383e1493..02b42ddd5 100644
--- a/module/zfs/vdev_trim.c
+++ b/module/zfs/vdev_trim.c
@@ -317,7 +317,7 @@ vdev_trim_change_state(vdev_t *vd, vdev_trim_state_t new_state,
 	dmu_tx_t *tx = dmu_tx_create_dd(spa_get_dsl(spa)->dp_mos_dir);
 	VERIFY0(dmu_tx_assign(tx, TXG_WAIT));
 	dsl_sync_task_nowait(spa_get_dsl(spa), vdev_trim_zap_update_sync,
-	    guid, 2, ZFS_SPACE_CHECK_NONE, tx);
+	    guid, tx);
 
 	switch (new_state) {
 	case VDEV_TRIM_ACTIVE:
@@ -510,8 +510,7 @@ vdev_trim_range(trim_args_t *ta, uint64_t start, uint64_t size)
 
 		/* This is the first write of this txg. */
 		dsl_sync_task_nowait(spa_get_dsl(spa),
-		    vdev_trim_zap_update_sync, guid, 2,
-		    ZFS_SPACE_CHECK_RESERVED, tx);
+		    vdev_trim_zap_update_sync, guid, tx);
 	}
 
 	/*