From 0fb16ac8b0eae0bc1b0153bb3df02b9be4c48f85 Mon Sep 17 00:00:00 2001
From: Guillaume Rose <guillaume.rose@docker.com>
Date: Sat, 8 Jun 2019 22:57:37 +0200
Subject: [PATCH] =?UTF-8?q?Don=E2=80=99t=20resize=20dos=20partition=20if?=
 =?UTF-8?q?=20no=20free=20space=20is=20available?=
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Signed-off-by: Guillaume Rose <guillaume.rose@docker.com>
---
 pkg/extend/extend.go | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/pkg/extend/extend.go b/pkg/extend/extend.go
index 7bf88baad..3a88d1445 100644
--- a/pkg/extend/extend.go
+++ b/pkg/extend/extend.go
@@ -11,6 +11,7 @@ import (
 	"path/filepath"
 	"regexp"
 	"sort"
+	"strconv"
 	"strings"
 	"syscall"
 	"time"
@@ -87,6 +88,20 @@ func extend(d, fsType string) error {
 		log.Printf("No free space on device to extend partition")
 		return nil
 	}
+	if f.PartitionTable.Label == "dos" {
+		out, err := exec.Command("blockdev", "--getsz", d).Output()
+		if err != nil {
+			return fmt.Errorf("Unable to get total size of %s: %v", d, err)
+		}
+		totalSize, err := strconv.Atoi(strings.TrimSpace(string(out)))
+		if err != nil {
+			return fmt.Errorf("Unable to convert total size from string to int: %v", err)
+		}
+		if partition.Start+partition.Size == totalSize {
+			log.Printf("No free space on device to extend partition")
+			return nil
+		}
+	}
 
 	switch fsType {
 	case "ext4":