From 3a1d55db16aaa3d82c4ddd1f7f1543585e80af6b Mon Sep 17 00:00:00 2001
From: Rakshith R <rar@redhat.com>
Date: Tue, 11 Jul 2023 12:36:08 +0530
Subject: [PATCH] rbd: do not execute rbd sparsify when volume is in use

This commit makes sure sparsify() is not run when rbd
image is in use.
Running rbd sparsify with workload doing io and too
frequently is not desirable.
When a image is in use fstrim is run and sparsify will
be run only when image is not mapped.

Signed-off-by: Rakshith R <rar@redhat.com>
(cherry picked from commit 98fdadfde77adc16b578e550d4327b6d43ce0a6c)

# Conflicts:
#	internal/rbd/errors.go
---
 internal/csi-addons/rbd/reclaimspace.go |  9 +++++++++
 internal/rbd/diskusage.go               | 11 +++++++++++
 internal/rbd/errors.go                  |  2 ++
 3 files changed, 22 insertions(+)

diff --git a/internal/csi-addons/rbd/reclaimspace.go b/internal/csi-addons/rbd/reclaimspace.go
index 0d7d819da..725296544 100644
--- a/internal/csi-addons/rbd/reclaimspace.go
+++ b/internal/csi-addons/rbd/reclaimspace.go
@@ -18,11 +18,13 @@ package rbd
 
 import (
 	"context"
+	"errors"
 	"fmt"
 
 	csicommon "github.com/ceph/ceph-csi/internal/csi-common"
 	rbdutil "github.com/ceph/ceph-csi/internal/rbd"
 	"github.com/ceph/ceph-csi/internal/util"
+	"github.com/ceph/ceph-csi/internal/util/log"
 
 	"github.com/container-storage-interface/spec/lib/go/csi"
 	rs "github.com/csi-addons/spec/lib/go/reclaimspace"
@@ -69,6 +71,13 @@ func (rscs *ReclaimSpaceControllerServer) ControllerReclaimSpace(
 	defer rbdVol.Destroy()
 
 	err = rbdVol.Sparsify()
+	if errors.Is(err, rbdutil.ErrImageInUse) {
+		// FIXME: https://github.com/csi-addons/kubernetes-csi-addons/issues/406.
+		// treat sparsify call as no-op if volume is in use.
+		log.DebugLog(ctx, fmt.Sprintf("volume with ID %q is in use, skipping sparsify operation", volumeID))
+
+		return &rs.ControllerReclaimSpaceResponse{}, nil
+	}
 	if err != nil {
 		// TODO: check for different error codes?
 		return nil, status.Errorf(codes.Internal, "failed to sparsify volume %q: %s", rbdVol, err.Error())
diff --git a/internal/rbd/diskusage.go b/internal/rbd/diskusage.go
index efb12f37c..444a5a604 100644
--- a/internal/rbd/diskusage.go
+++ b/internal/rbd/diskusage.go
@@ -23,7 +23,18 @@ import (
 // Sparsify checks the size of the objects in the RBD image and calls
 // rbd_sparify() to free zero-filled blocks and reduce the storage consumption
 // of the image.
+// This function will return ErrImageInUse if the image is in use, since
+// sparsifying an image on which i/o is in progress is not optimal.
 func (ri *rbdImage) Sparsify() error {
+	inUse, err := ri.isInUse()
+	if err != nil {
+		return fmt.Errorf("failed to check if image is in use: %w", err)
+	}
+	if inUse {
+		// if the image is in use, we should not sparsify it, return ErrImageInUse.
+		return ErrImageInUse
+	}
+
 	image, err := ri.open()
 	if err != nil {
 		return err
diff --git a/internal/rbd/errors.go b/internal/rbd/errors.go
index afcc7a839..ae7b58d25 100644
--- a/internal/rbd/errors.go
+++ b/internal/rbd/errors.go
@@ -45,4 +45,6 @@ var (
 	// ErrLastSyncTimeNotFound is returned when last sync time is not found for
 	// the image.
 	ErrLastSyncTimeNotFound = errors.New("last sync time not found")
+	// ErrImageInUse is returned when the image is in use.
+	ErrImageInUse = errors.New("image is in use")
 )