Correct wrong check of resulting image sparsiness

Following 2168 the check for sparsiness is not always honest.
<EXPLANATION>

Signed-off-by: Alex Kalenyuk <[email protected]>

tests/framework/pvc.go

@@ -8,7 +8,6 @@ import (
 	"strings"
 	"time"
 
-	"github.com/docker/go-units"
 	"github.com/onsi/ginkgo/v2"
 	"github.com/onsi/gomega"
 	k8sv1 "k8s.io/api/core/v1"
@@ -283,23 +282,17 @@ func (f *Framework) VerifyBlankDisk(namespace *k8sv1.Namespace, pvc *k8sv1.Persi
 
 // VerifySparse checks a disk image being sparse after creation/resize.
 func (f *Framework) VerifySparse(namespace *k8sv1.Namespace, pvc *k8sv1.PersistentVolumeClaim, imagePath string) (bool, error) {
-	var info image.ImgInfo
-	var imageContentSize int64
-	err := f.GetImageInfo(namespace, pvc, imagePath, &info)
-	if err != nil {
-		return false, err
-	}
-	// qemu-img info gives us ActualSize but that is size on disk
-	// which isn't important to us in this comparison; we compare content size
-	err = f.GetImageContentSize(namespace, pvc, imagePath, &imageContentSize)
-	if err != nil {
-		return false, err
-	}
-	if info.ActualSize-imageContentSize >= units.MiB {
-		return false, fmt.Errorf("Diff between content size %d and size on disk %d is significant, something's not right", imageContentSize, info.ActualSize)
-	}
-	fmt.Fprintf(ginkgo.GinkgoWriter, "INFO: VerifySparse comparison: Virtual: %d vs Content: %d\n", info.VirtualSize, imageContentSize)
-	return info.VirtualSize >= imageContentSize, nil
+	cmd := "find " + imagePath + ` -printf "%S"`
+
+	return f.verifyInPod(namespace, pvc, cmd, func(output, stderr string) (bool, error) {
+		fmt.Fprintf(ginkgo.GinkgoWriter, "INFO: output of cmd to find sparseness: %s\n", output)
+		sparseness, err := strconv.ParseFloat(strings.TrimSpace(output), 64)
+		if err != nil {
+			return false, err
+		}
+
+		return sparseness < 1.0, nil
+	})
 }
 
 // VerifyFSOverhead checks whether virtual size is smaller than actual size. That means FS Overhead has been accounted for.
@@ -546,26 +539,6 @@ func (f *Framework) GetImageInfo(namespace *k8sv1.Namespace, pvc *k8sv1.Persiste
 	return err
 }
 
-// GetImageContentSize returns the content size (as opposed to size on disk) of an image
-func (f *Framework) GetImageContentSize(namespace *k8sv1.Namespace, pvc *k8sv1.PersistentVolumeClaim, imagePath string, imageSize *int64) error {
-	cmd := fmt.Sprintf("du -s --apparent-size -B 1 %s | cut -f 1", imagePath)
-
-	_, err := f.verifyInPod(namespace, pvc, cmd, func(output, stderr string) (bool, error) {
-		fmt.Fprintf(ginkgo.GinkgoWriter, "CMD (%s) output %s\n", cmd, output)
-
-		size, err := strconv.ParseInt(output, 10, 64)
-		if err != nil {
-			klog.Errorf("Invalid image content size:\n%s\n", output)
-			return false, err
-		}
-		*imageSize = size
-
-		return true, nil
-	})
-
-	return err
-}
-
 func (f *Framework) startVerifierPod(namespace *k8sv1.Namespace, pvc *k8sv1.PersistentVolumeClaim) (*k8sv1.Pod, error) {
 	var executorPod *k8sv1.Pod
 	var err error