fix: choose appropriate quorum for a given erasure set (#13998)

multiObject delete should honor expected quorum

cmd/erasure-bucket.go

@@ -64,8 +64,7 @@ func (er erasureObjects) MakeBucketWithLocation(ctx context.Context, bucket stri
 		}, index)
 	}
 
-	writeQuorum := getWriteQuorum(len(storageDisks))
-	err := reduceWriteQuorumErrs(ctx, g.Wait(), bucketOpIgnoredErrs, writeQuorum)
+	err := reduceWriteQuorumErrs(ctx, g.Wait(), bucketOpIgnoredErrs, er.defaultWQuorum())
 	return toObjectErr(err, bucket)
 }
 
@@ -121,8 +120,7 @@ func (er erasureObjects) getBucketInfo(ctx context.Context, bucketName string) (
 	// reduce to one error based on read quorum.
 	// `nil` is deliberately passed for ignoredErrs
 	// because these errors were already ignored.
-	readQuorum := getReadQuorum(len(storageDisks))
-	return BucketInfo{}, reduceReadQuorumErrs(ctx, errs, nil, readQuorum)
+	return BucketInfo{}, reduceReadQuorumErrs(ctx, errs, nil, er.defaultRQuorum())
 }
 
 // GetBucketInfo - returns BucketInfo for a bucket.
@@ -167,8 +165,7 @@ func (er erasureObjects) DeleteBucket(ctx context.Context, bucket string, opts D
 		return nil
 	}
 
-	writeQuorum := getWriteQuorum(len(storageDisks))
-	err := reduceWriteQuorumErrs(ctx, dErrs, bucketOpIgnoredErrs, writeQuorum)
+	err := reduceWriteQuorumErrs(ctx, dErrs, bucketOpIgnoredErrs, er.defaultWQuorum())
 	if err == errErasureWriteQuorum && !opts.NoRecreate {
 		undoDeleteBucket(storageDisks, bucket)
 	}

cmd/erasure-object.go

@@ -498,7 +498,7 @@ func (er erasureObjects) getObjectInfo(ctx context.Context, bucket, object strin
 func (er erasureObjects) getObjectInfoAndQuorum(ctx context.Context, bucket, object string, opts ObjectOptions) (objInfo ObjectInfo, wquorum int, err error) {
 	fi, _, _, err := er.getObjectFileInfo(ctx, bucket, object, opts, false)
 	if err != nil {
-		return objInfo, getWriteQuorum(len(er.getDisks())), toObjectErr(err, bucket, object)
+		return objInfo, er.defaultWQuorum(), toObjectErr(err, bucket, object)
 	}
 
 	wquorum = fi.Erasure.DataBlocks
@@ -1113,7 +1113,7 @@ func (er erasureObjects) DeleteObjects(ctx context.Context, bucket string, objec
 		// class for objects which have reduced quorum
 		// storage class only needs to be honored for
 		// Read() requests alone which we already do.
-		writeQuorums[i] = getWriteQuorum(len(storageDisks))
+		writeQuorums[i] = er.defaultWQuorum()
 	}
 
 	versionsMap := make(map[string]FileInfoVersions, len(objects))
@@ -1600,7 +1600,7 @@ func (er erasureObjects) updateObjectMeta(ctx context.Context, bucket, object st
 	// Wait for all the routines.
 	mErrs := g.Wait()
 
-	return reduceWriteQuorumErrs(ctx, mErrs, objectOpIgnoredErrs, getWriteQuorum(len(onlineDisks)))
+	return reduceWriteQuorumErrs(ctx, mErrs, objectOpIgnoredErrs, er.defaultWQuorum())
 }
 
 // DeleteObjectTags - delete object tags from an existing object

cmd/erasure.go

@@ -84,6 +84,19 @@ func (er erasureObjects) Shutdown(ctx context.Context) error {
 	return nil
 }
 
+// defaultWQuorum write quorum based on setDriveCount and defaultParityCount
+func (er erasureObjects) defaultWQuorum() int {
+	dataCount := er.setDriveCount - er.defaultParityCount
+	if dataCount == er.defaultParityCount {
+		return dataCount + 1
+	}
+	return dataCount
+}
+
+func (er erasureObjects) defaultRQuorum() int {
+	return er.setDriveCount - er.defaultParityCount
+}
+
 // byDiskTotal is a collection satisfying sort.Interface.
 type byDiskTotal []madmin.Disk
 

cmd/metacache-set.go

@@ -544,7 +544,7 @@ func (er *erasureObjects) listPath(ctx context.Context, o listPathOptions, resul
 	// Special case: ask all disks if the drive count is 4
 	if askDisks == -1 || er.setDriveCount == 4 {
 		askDisks = len(disks) // with 'strict' quorum list on all online disks.
-		listingQuorum = getReadQuorum(er.setDriveCount)
+		listingQuorum = er.defaultRQuorum()
 	}
 	if askDisks == 0 {
 		askDisks = globalAPIConfig.getListQuorum()