rbd: consider ErrPermissionDenied for vol

Incase of RDR with restricted access the
ceph user will not have access to all the objects
or all the pools where mapping exists

This commits add a check to continue to get
the volume if there is a permission error

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>

internal/rbd/rbd_util_test.go

@@ -23,8 +23,11 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/ceph/go-ceph/rados"
 	librbd "github.com/ceph/go-ceph/rbd"
 	"github.com/stretchr/testify/require"
+
+	"github.com/ceph/ceph-csi/internal/util"
 )
 
 func TestHasSnapshotFeature(t *testing.T) {
@@ -387,3 +390,54 @@ func Test_checkValidImageFeatures(t *testing.T) {
 		})
 	}
 }
+
+func Test_shouldRetryVolumeGeneration(t *testing.T) {
+	t.Parallel()
+	type args struct {
+		err error
+	}
+	tests := []struct {
+		name string
+		args args
+		want bool
+	}{
+		{
+			name: "No error (stop searching)",
+			args: args{err: nil},
+			want: false, // No error, stop searching
+		},
+		{
+			name: "ErrKeyNotFound (continue searching)",
+			args: args{err: util.ErrKeyNotFound},
+			want: true, // Known error, continue searching
+		},
+		{
+			name: "ErrPoolNotFound (continue searching)",
+			args: args{err: util.ErrPoolNotFound},
+			want: true, // Known error, continue searching
+		},
+		{
+			name: "ErrImageNotFound (continue searching)",
+			args: args{err: ErrImageNotFound},
+			want: true, // Known error, continue searching
+		},
+		{
+			name: "ErrPermissionDenied (continue searching)",
+			args: args{err: rados.ErrPermissionDenied},
+			want: true, // Known error, continue searching
+		},
+		{
+			name: "Different error (stop searching)",
+			args: args{err: errors.New("unknown error")},
+			want: false, // Unknown error, stop searching
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+			if got := shouldRetryVolumeGeneration(tt.args.err); got != tt.want {
+				t.Errorf("shouldRetryVolumeGeneration() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}