From 6e9c8533121528bb27daee97a68c06b2f637f872 Mon Sep 17 00:00:00 2001
From: Harshavardhana <harsha@minio.io>
Date: Tue, 27 Mar 2018 18:11:39 -0700
Subject: [PATCH] After healing re-load disks with the new format (#5718)

This PR also fixes correct calculation of drive states
before and after healing of objects.

Fixes #5700
Fixes #5708
---
 cmd/xl-sets.go       | 49 ++++++++++++++++++++++++++------------------
 cmd/xl-v1-healing.go | 21 ++++++++++---------
 cmd/xl-v1.go         |  6 ++++++
 3 files changed, 46 insertions(+), 30 deletions(-)

diff --git a/cmd/xl-sets.go b/cmd/xl-sets.go
index 78c9ab69e..924c6ce5c 100644
--- a/cmd/xl-sets.go
+++ b/cmd/xl-sets.go
@@ -131,6 +131,31 @@ func findDiskIndex(refFormat, format *formatXLV3) (int, int, error) {
 	return -1, -1, fmt.Errorf("diskID: %s not found", format.XL.This)
 }
 
+// connectDisks - attempt to connect all the endpoints, loads format
+// and re-arranges the disks in proper position.
+func (s *xlSets) connectDisks() {
+	for _, endpoint := range s.endpoints {
+		if s.isConnected(endpoint) {
+			continue
+		}
+		disk, format, err := connectEndpoint(endpoint)
+		if err != nil {
+			printEndpointError(endpoint, err)
+			continue
+		}
+		s.formatMu.RLock()
+		i, j, err := findDiskIndex(s.format, format)
+		s.formatMu.RUnlock()
+		if err != nil {
+			printEndpointError(endpoint, err)
+			continue
+		}
+		s.xlDisksMu.Lock()
+		s.xlDisks[i][j] = disk
+		s.xlDisksMu.Unlock()
+	}
+}
+
 // monitorAndConnectEndpoints this is a monitoring loop to keep track of disconnected
 // endpoints by reconnecting them and making sure to place them into right position in
 // the set topology, this monitoring happens at a given monitoring interval.
@@ -143,26 +168,7 @@ func (s *xlSets) monitorAndConnectEndpoints(doneCh chan struct{}, monitorInterva
 			ticker.Stop()
 			return
 		case <-ticker.C:
-			for _, endpoint := range s.endpoints {
-				if s.isConnected(endpoint) {
-					continue
-				}
-				disk, format, err := connectEndpoint(endpoint)
-				if err != nil {
-					printEndpointError(endpoint, err)
-					continue
-				}
-				s.formatMu.RLock()
-				i, j, err := findDiskIndex(s.format, format)
-				s.formatMu.RUnlock()
-				if err != nil {
-					printEndpointError(endpoint, err)
-					continue
-				}
-				s.xlDisksMu.Lock()
-				s.xlDisks[i][j] = disk
-				s.xlDisksMu.Unlock()
-			}
+			s.connectDisks()
 		}
 	}
 }
@@ -1036,6 +1042,9 @@ func (s *xlSets) HealFormat(ctx context.Context, dryRun bool) (madmin.HealResult
 		s.formatMu.Lock()
 		s.format = refFormat
 		s.formatMu.Unlock()
+
+		// Connect disks, after saving the new reference format.
+		s.connectDisks()
 	}
 
 	return res, nil
diff --git a/cmd/xl-v1-healing.go b/cmd/xl-v1-healing.go
index 517124e3b..6f1c679a5 100644
--- a/cmd/xl-v1-healing.go
+++ b/cmd/xl-v1-healing.go
@@ -338,20 +338,24 @@ func healObject(storageDisks []StorageAPI, bucket string, object string,
 			outDatedDisks[i] = storageDisks[i]
 			disksToHealCount++
 		}
+		var drive string
 		if v == nil {
+			if errs[i] != errDiskNotFound {
+				drive = outDatedDisks[i].String()
+			}
 			result.Before.Drives = append(result.Before.Drives, madmin.HealDriveInfo{
 				UUID:     "",
-				Endpoint: "",
+				Endpoint: drive,
 				State:    driveState,
 			})
 			result.After.Drives = append(result.After.Drives, madmin.HealDriveInfo{
 				UUID:     "",
-				Endpoint: "",
+				Endpoint: drive,
 				State:    driveState,
 			})
 			continue
 		}
-		drive := v.String()
+		drive = v.String()
 		result.Before.Drives = append(result.Before.Drives, madmin.HealDriveInfo{
 			UUID:     "",
 			Endpoint: drive,
@@ -492,7 +496,7 @@ func healObject(storageDisks []StorageAPI, bucket string, object string,
 	}
 
 	// Rename from tmp location to the actual location.
-	for diskIndex, disk := range outDatedDisks {
+	for _, disk := range outDatedDisks {
 		if disk == nil {
 			continue
 		}
@@ -504,12 +508,9 @@ func healObject(storageDisks []StorageAPI, bucket string, object string,
 			return result, toObjectErr(errors.Trace(aErr), bucket, object)
 		}
 
-		realDiskIdx := unshuffleIndex(diskIndex, latestMeta.Erasure.Distribution)
-		if outDatedDisks[realDiskIdx] != nil {
-			for i, v := range result.After.Drives {
-				if v.Endpoint == outDatedDisks[realDiskIdx].String() {
-					result.After.Drives[i].State = madmin.DriveStateOk
-				}
+		for i, v := range result.Before.Drives {
+			if v.Endpoint == disk.String() {
+				result.After.Drives[i].State = madmin.DriveStateOk
 			}
 		}
 	}
diff --git a/cmd/xl-v1.go b/cmd/xl-v1.go
index aa1fa7b6f..9023f68b8 100644
--- a/cmd/xl-v1.go
+++ b/cmd/xl-v1.go
@@ -197,6 +197,12 @@ func getStorageInfo(disks []StorageAPI) StorageInfo {
 	// This is the number of drives we report free and total space for
 	availableDataDisks := uint64(onlineDisks - sscParity)
 
+	// Available data disks can be zero when onlineDisks is equal to parity,
+	// at that point we simply choose online disks to calculate the size.
+	if availableDataDisks == 0 {
+		availableDataDisks = uint64(onlineDisks)
+	}
+
 	// Return calculated storage info, choose the lowest Total and
 	// Free as the total aggregated values. Total capacity is always
 	// the multiple of smallest disk among the disk list.