From dc415e04837a816ef8656b2eab5125069e3b1107 Mon Sep 17 00:00:00 2001
From: TanYiFeng <tanyifeng1@huawei.com>
Date: Tue, 9 Apr 2019 12:19:49 -0400
Subject: [PATCH 04/37] isulad-kit-vendor: check overlay support as docker

we may got failed if always detect multi lower layer mount,
when writed data more than rootfs quota for arm machine

Signed-off-by: TanYiFeng <tanyifeng1@huawei.com>
---
 .../storage/drivers/overlay/overlay.go        | 42 ++++++++++++-------
 1 file changed, 26 insertions(+), 16 deletions(-)

diff --git a/vendor/github.com/containers/storage/drivers/overlay/overlay.go b/vendor/github.com/containers/storage/drivers/overlay/overlay.go
index 5561658..26467d1 100644
--- a/vendor/github.com/containers/storage/drivers/overlay/overlay.go
+++ b/vendor/github.com/containers/storage/drivers/overlay/overlay.go
@@ -34,6 +34,7 @@ import (
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 	"golang.org/x/sys/unix"
+	"bufio"
 )
 
 var (
@@ -131,6 +132,10 @@ func Init(home string, options []string, uidMaps, gidMaps []idtools.IDMap) (grap
 		return nil, err
 	}
 
+	if err := supportsOverlay(); err != nil {
+		return nil, graphdriver.ErrNotSupported
+	}
+
 	fsMagic, err := graphdriver.GetFSMagic(home)
 	if err != nil {
 		return nil, err
@@ -162,11 +167,11 @@ func Init(home string, options []string, uidMaps, gidMaps []idtools.IDMap) (grap
 	if opts.mountProgram != "" {
 		supportsDType = true
 	} else {
-		supportsDType, err = supportsOverlay(home, fsMagic, rootUID, rootGID)
-		if err != nil {
+		supportsDType, err = fsutils.SupportsDType(home)
+		if !supportsDType {
 			os.Remove(filepath.Join(home, linkDir))
 			os.Remove(home)
-			return nil, errors.Wrap(err, "kernel does not support overlay fs")
+			return nil, overlayutils.ErrDTypeNotSupported("overlay", backingFs)
 		}
 	}
 
@@ -300,23 +305,28 @@ func parseOptions(options []string) (*overlayOptions, error) {
 	return o, nil
 }
 
-func supportsOverlay(home string, homeMagic graphdriver.FsMagic, rootUID, rootGID int) (supportsDType bool, err error) {
-	// We can try to modprobe overlay first
-
+func supportsOverlay() error {
 	exec.Command("modprobe", "overlay").Run()
 
-	layerDir, err := ioutil.TempDir(home, "compat")
-	if err == nil {
-		// Check if reading the directory's contents populates the d_type field, which is required
-		// for proper operation of the overlay filesystem.
-		supportsDType, err = fsutils.SupportsDType(layerDir)
-		if err != nil {
-			return false, err
-		}
-		if !supportsDType {
-			return false, overlayutils.ErrDTypeNotSupported("overlay", backingFs)
+	f, err := os.Open("/proc/filesystems")
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	s := bufio.NewScanner(f)
+	for s.Scan() {
+		if s.Text() == "nodev\toverlay" {
+			return nil
 		}
+	}
+	logrus.Errorf("'overlay' not found as a supported filesystem on this host. Please ensure kernel is new enough and has overlay support loaded.")
+	return graphdriver.ErrNotSupported
+}
 
+func supportsMultipleLowerDir(home string, homeMagic graphdriver.FsMagic, rootUID, rootGID int) (supportsDType bool, err error) {
+	layerDir, err := ioutil.TempDir(home, "compat")
+	if err == nil {
 		// Try a test mount in the specific location we're looking at using.
 		mergedDir := filepath.Join(layerDir, "merged")
 		lower1Dir := filepath.Join(layerDir, "lower1")
-- 
2.19.1