From 4ef7f0d024ced9b023eb2e47f02e325c959ad446 Mon Sep 17 00:00:00 2001
From: Achilleas Koutsou <achilleas@koutsou.net>
Date: Wed, 24 Jul 2024 22:32:02 +0200
Subject: [PATCH] disk: test relayout() function fix

Add two new test cases, dos and gpt with LVM, that force the VG
partition and partition table to grow to fit the LVs.  The partition
size calculation can be a bit hard to follow with metadata and rounding,
but the comments should help.
---
 pkg/disk/partition_table_internal_test.go | 111 +++++++++++++++++++++-
 1 file changed, 110 insertions(+), 1 deletion(-)

diff --git a/pkg/disk/partition_table_internal_test.go b/pkg/disk/partition_table_internal_test.go
index eea076508e..3c71c56388 100644
--- a/pkg/disk/partition_table_internal_test.go
+++ b/pkg/disk/partition_table_internal_test.go
@@ -478,7 +478,6 @@ func TestRelayout(t *testing.T) {
 									Payload: &Filesystem{
 										Mountpoint: "/",
 									},
-									// TODO: fix bug where the VG partition is not resized to fit the sum of LVs
 									Size: 10 * MiB,
 								},
 							},
@@ -691,6 +690,116 @@ func TestRelayout(t *testing.T) {
 				},
 			},
 		},
+		"lvm-dos-grow-rootvg": {
+			pt: &PartitionTable{
+				Type: "dos",
+				Size: 10 * MiB, // PT is smaller than the sum of Partitions
+				Partitions: []Partition{
+					{
+						Size: 200 * MiB,
+					},
+					{
+						Size: 10 * MiB, // VG partition is smaller than sum of LVs
+						Payload: &LVMVolumeGroup{
+							LogicalVolumes: []LVMLogicalVolume{
+								{
+									Size: 20 * MiB,
+								},
+								{
+									Payload: &Filesystem{
+										Mountpoint: "/",
+									},
+									Size: 100 * MiB,
+								},
+							},
+						},
+					},
+				},
+			},
+			size: 99 * MiB,
+			expected: &PartitionTable{
+				Type: "dos",
+				Size: 325 * MiB,
+				Partitions: []Partition{
+					{
+						Start: 1 * MiB, // 1 sector header aligned up to the default grain (1 MiB)
+						Size:  200 * MiB,
+					},
+					{
+						Start: 201 * MiB,
+						Size:  124 * MiB, // grows to fit logical volumes + 1 MiB metadata, rounded up to default extent size (4 MiB)
+						Payload: &LVMVolumeGroup{
+							LogicalVolumes: []LVMLogicalVolume{
+								{
+									Size: 20 * MiB,
+								},
+								{
+									Payload: &Filesystem{
+										Mountpoint: "/",
+									},
+									Size: 100 * MiB,
+								},
+							},
+						},
+					},
+				},
+			},
+		},
+		"lvm-gpt-grow-rootvg": {
+			pt: &PartitionTable{
+				Type: "gpt",
+				Size: 10 * MiB,
+				Partitions: []Partition{
+					{
+						Size: 200 * MiB,
+					},
+					{
+						Size: 10 * MiB,
+						Payload: &LVMVolumeGroup{
+							LogicalVolumes: []LVMLogicalVolume{
+								{
+									Size: 20 * MiB,
+								},
+								{
+									Payload: &Filesystem{
+										Mountpoint: "/",
+									},
+									Size: 100 * MiB,
+								},
+							},
+						},
+					},
+				},
+			},
+			size: 99 * MiB,
+			expected: &PartitionTable{
+				Type: "gpt",
+				Size: 326 * MiB,
+				Partitions: []Partition{
+					{
+						Start: 1 * MiB, // 1 sector header aligned up to the default grain (1 MiB)
+						Size:  200 * MiB,
+					},
+					{
+						Start: 201 * MiB,
+						Size:  125*MiB - (DefaultSectorSize + (128 * 128)), // grows to fit logical volumes and metadata, rounded up to default extent size + (1 MiB - footer) so that the no partitions shrink below the desired sizes
+						Payload: &LVMVolumeGroup{
+							LogicalVolumes: []LVMLogicalVolume{
+								{
+									Size: 20 * MiB,
+								},
+								{
+									Payload: &Filesystem{
+										Mountpoint: "/",
+									},
+									Size: 100 * MiB,
+								},
+							},
+						},
+					},
+				},
+			},
+		},
 	}
 
 	for name := range testCases {