From 6d14eeee70b7fb99e23723fe5164cb414d4caff6 Mon Sep 17 00:00:00 2001
From: Madhu Rajanna <madhupr007@gmail.com>
Date: Thu, 17 Jun 2021 18:21:28 +0530
Subject: [PATCH] rbd: use RbdSnapName to check the image details

RbdSnapName holds the actual RBD image name which
got created during the CreateSnapshot operation.
RbdImageName holds the name of the parent from
which the snapshot is created. and the parent
is independent of snapshot and it can be deleted
any time for the same reason using the RbdSnapName
to check the rbd image details.

generate a temporary volume from the snapshot which
replaces the rbdImageName with RbdSnapName and use
it to check the image metadata.

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>
---
 internal/rbd/rbd_util.go | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/internal/rbd/rbd_util.go b/internal/rbd/rbd_util.go
index ae6c769bc..a6cb3658a 100644
--- a/internal/rbd/rbd_util.go
+++ b/internal/rbd/rbd_util.go
@@ -1629,3 +1629,31 @@ func (ri *rbdImage) isCompatibleThickProvision(dst *rbdVolume) error {
 
 	return nil
 }
+
+// FIXME: merge isCompatibleThickProvision of rbdSnapshot and rbdImage to a single
+// function.
+func (rs *rbdSnapshot) isCompatibleThickProvision(dst *rbdVolume) error {
+	// During CreateSnapshot the rbd image will be created with the
+	// snapshot name. Replacing RbdImageName with RbdSnapName so that we
+	// can check if the image is thick provisioned
+	vol := generateVolFromSnap(rs)
+	err := vol.Connect(rs.conn.Creds)
+	if err != nil {
+		return err
+	}
+	defer vol.Destroy()
+
+	thick, err := vol.isThickProvisioned()
+	if err != nil {
+		return err
+	}
+	switch {
+	case thick && !dst.ThickProvision:
+		return fmt.Errorf("cannot create thin volume from thick volume %q", vol)
+
+	case !thick && dst.ThickProvision:
+		return fmt.Errorf("cannot create thick volume from thin volume %q", vol)
+	}
+
+	return nil
+}