Do not use inline data size in xl.meta quorum calculation (#14831)

* Do not use inline data size in xl.meta quorum calculation

Data shards of one object can different inline/not-inline decision
in multiple disks. This happens with outdated disks when inline
decision changes. For example, enabling bucket versioning configuration
will change the small file threshold.

When the parity of an object becomes low, GET object can return 503
because it is not unable to calculate the xl.meta quorum, just because
some xl.meta has inline data and other are not.

So this commit will be disable taking the size of the inline data into
consideration when calculating the xl.meta quorum.

* Add tests for simulatenous inline/notinline object

Co-authored-by: Anis Elleuch <anis@min.io>

cmd/erasure-object_test.go

@@ -20,11 +20,14 @@ package cmd
 import (
 	"bytes"
 	"context"
+	"crypto/md5"
 	crand "crypto/rand"
 	"errors"
+	"fmt"
 	"io"
 	"io/ioutil"
 	"os"
+	"path/filepath"
 	"strconv"
 	"testing"
 
@@ -1048,3 +1051,63 @@ func testObjectQuorumFromMeta(obj ObjectLayer, instanceType string, dirs []strin
 		})
 	}
 }
+
+// In some deployments, one object has data inlined in one disk and not inlined in other disks.
+func TestGetObjectInlineNotInline(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	// Create a backend with 4 disks named disk{1...4}, this name convention
+	// because we will unzip some object data from a sample archive.
+	const numDisks = 4
+	path, err := ioutil.TempDir(globalTestTmpDir, "minio-")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var fsDirs []string
+	for i := 1; i <= numDisks; i++ {
+		fsDirs = append(fsDirs, filepath.Join(path, fmt.Sprintf("disk%d", i)))
+	}
+
+	objLayer, _, err := initObjectLayer(ctx, mustGetPoolEndpoints(fsDirs...))
+	if err != nil {
+		removeRoots(fsDirs)
+		t.Fatal(err)
+	}
+
+	// cleaning up of temporary test directories
+	defer objLayer.Shutdown(context.Background())
+	defer removeRoots(fsDirs)
+
+	// Create a testbucket
+	err = objLayer.MakeBucketWithLocation(ctx, "testbucket", BucketOptions{})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Unzip sample object data to the existing disks
+	err = unzipArchive("testdata/xl-meta-inline-notinline.zip", path)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Try to read the object and check its md5sum
+	gr, err := objLayer.GetObjectNInfo(ctx, "testbucket", "file", nil, nil, readLock, ObjectOptions{})
+	if err != nil {
+		t.Fatalf("Expected GetObject to succeed, but failed with %v", err)
+	}
+
+	h := md5.New()
+	_, err = io.Copy(h, gr)
+	if err != nil {
+		t.Fatalf("Expected GetObject reading data to succeed, but failed with %v", err)
+	}
+	gr.Close()
+
+	const expectedHash = "fffb6377948ebea75ad2b8058e849ef5"
+	foundHash := fmt.Sprintf("%x", h.Sum(nil))
+	if foundHash != expectedHash {
+		t.Fatalf("Expected data to have md5sum = `%s`, found `%s`", expectedHash, foundHash)
+	}
+}