ddl: create temp dir automatically for adding index

ddl/ingest/disk_root.go

@@ -16,12 +16,14 @@
 
 import (
 	"fmt"
+	"os"
 	"sync"
 	"sync/atomic"
 
 	"github.com/pingcap/errors"
 	lcom "github.com/pingcap/tidb/br/pkg/lightning/common"
 	"github.com/pingcap/tidb/sessionctx/variable"
+	"github.com/pingcap/tidb/util/dbterror"
 	"github.com/pingcap/tidb/util/logutil"
 	"go.uber.org/zap"
 )
@@ -114,13 +116,18 @@
 
 // PreCheckUsage implements DiskRoot interface.
 func (d *diskRootImpl) PreCheckUsage() error {
+	err := os.MkdirAll(d.path, 0700)
+	if err != nil {
+		return dbterror.ErrIngestFailed.FastGenByArgs(err.Error())
+	}
 	sz, err := lcom.GetStorageSize(d.path)
 	if err != nil {
-		return errors.Trace(err)
+		return dbterror.ErrIngestFailed.FastGenByArgs(err.Error())
 	}
 	if RiskOfDiskFull(sz.Available, sz.Capacity) {
 		sortPath := ConfigSortPath()
-		return errors.Errorf("sort path: %s, %s, please clean up the disk and retry", sortPath, d.UsageInfo())
+		msg := fmt.Sprintf("sort path: %s, %s, please clean up the disk and retry", sortPath, d.UsageInfo())
+		return dbterror.ErrIngestFailed.FastGenByArgs(msg)
 	}
 	return nil
 }