pkg/disk: add XFS agcount option in disk.yaml

doc/20-advanced/20-bootc/05-sources-of-configuration.md

@@ -99,6 +99,12 @@ For a `payload_type: filesystem` the `payload` has the following properties:
 - `fstab_options`
 - `fstab_freq`
 - `fstab_passno`
+- `mkfs_options`, an *optional* object containing filesystem-specific mkfs options. Currently supported properties:
+  - `verity`, an *optional* `boolean` to enable fs-verity (ext4 only).
+  - `geometry`, an *optional* object for drive geometry (vfat only), with the following properties:
+    - `heads`, an `integer` setting the number of heads.
+    - `sectors_per_track`, an `integer` setting the number of sectors per track.
+  - `agcount`, an *optional* `integer` setting the number of allocation groups (xfs only).
 
 Here's an example defining a few partition with XFS filesystem(s):
 
@@ -134,6 +140,32 @@ partition_table:
         mountpoint: "/"
 ```
 
+To pass custom mkfs options, use the `mkfs_options` field. For example, to set the XFS allocation group count:
+
+```yaml
+    - payload_type: "filesystem"
+      payload:
+        type: "xfs"
+        label: "root"
+        mountpoint: "/"
+        mkfs_options:
+          agcount: 4
+```
+
+Or to set custom drive geometry on a vfat partition:
+
+```yaml
+    - payload_type: "filesystem"
+      payload:
+        type: "vfat"
+        mountpoint: "/boot/efi"
+        label: "ESP"
+        mkfs_options:
+          geometry:
+            heads: 64
+            sectors_per_track: 32
+```
+
 ###### LVM
 
 > [!WARNING]

pkg/disk/filesystem.go

@@ -15,6 +15,7 @@ type MkfsOptionGeometry struct {
 type MkfsOptions struct {
 	Verity   bool                `json:"verity,omitempty" yaml:"verity,omitempty"`
 	Geometry *MkfsOptionGeometry `json:"geometry,omitempty" yaml:"geometry,omitempty"`
+	AGCount  int                 `json:"agcount,omitempty" yaml:"agcount,omitempty"`
 }
 
 func (opts MkfsOptions) Clone() MkfsOptions {

pkg/disk/filesystem_test.go

@@ -23,9 +23,9 @@ func TestMkfsOptionsClone(t *testing.T) {
 	orig := disk.MkfsOptions{
 		Verity:   true,
 		Geometry: &Geometry,
+		AGCount:  4,
 	}
 	clone := orig.Clone()
 	assert.Equal(t, orig, clone)
 	assert.False(t, reflect.ValueOf(orig.Geometry).Pointer() == reflect.ValueOf(clone.Geometry).Pointer())
-
 }

pkg/osbuild/mkfs_stage.go

@@ -45,6 +45,10 @@ func GenFsStages(pt *disk.PartitionTable, filename string, soucePipeline string)
 					UUID:  e.UUID,
 					Label: e.Label,
 				}
+				if mkfsOptions.AGCount != 0 {
+					options.AGCount = mkfsOptions.AGCount
+					mkfsOptions.AGCount = 0 // Handled
+				}
 				stages = append(stages, NewMkfsXfsStage(options, stageDevices))
 			case "vfat":
 				options := &MkfsFATStageOptions{
@@ -81,6 +85,9 @@ func GenFsStages(pt *disk.PartitionTable, filename string, soucePipeline string)
 			if mkfsOptions.Verity {
 				panic(fmt.Sprintf("fs type: %s does not support verity option", e.GetFSType()))
 			}
+			if mkfsOptions.AGCount != 0 {
+				panic(fmt.Sprintf("fs type: %s does not support agcount option", e.GetFSType()))
+			}
 
 		case *disk.Btrfs:
 			stageDevices := getDevicesForFsStage(path, filename)

pkg/osbuild/mkfs_stages_test.go

@@ -509,6 +509,33 @@ func TestGenFsStagesUnitVfatGeometry(t *testing.T) {
 	}, stages)
 }
 
+func TestGenFsStagesUnitXfsAGCount(t *testing.T) {
+	pt := &disk.PartitionTable{
+		Type: disk.PT_GPT,
+		Partitions: []disk.Partition{
+			{
+				Payload: &disk.Filesystem{
+					Type:       "xfs",
+					Mountpoint: "/",
+					MkfsOptions: disk.MkfsOptions{
+						AGCount: 4,
+					},
+				},
+			},
+		},
+	}
+	stages := GenFsStages(pt, "file.img", "build")
+	assert.Equal(t, []*Stage{
+		{
+			Type: "org.osbuild.mkfs.xfs",
+			Options: &MkfsXfsStageOptions{
+				AGCount: 4,
+			},
+			Devices: defaultStageDevices,
+		},
+	}, stages)
+}
+
 func TestGenFsStagesUnhappy(t *testing.T) {
 	pt := &disk.PartitionTable{
 		Type: disk.PT_GPT,
@@ -547,6 +574,26 @@ func TestGenFsStagesUnhappyWrongOptionsVerity(t *testing.T) {
 	})
 }
 
+func TestGenFsStagesUnhappyWrongOptionsAGCount(t *testing.T) {
+	pt := &disk.PartitionTable{
+		Type: disk.PT_GPT,
+		Partitions: []disk.Partition{
+			{
+				Payload: &disk.Filesystem{
+					Type: "ext4",
+					MkfsOptions: disk.MkfsOptions{
+						AGCount: 4,
+					},
+				},
+			},
+		},
+	}
+
+	assert.PanicsWithValue(t, "fs type: ext4 does not support agcount option", func() {
+		GenFsStages(pt, "file.img", "build")
+	})
+}
+
 func TestGenFsStagesUnhappyWrongOptionsGeometry(t *testing.T) {
 	pt := &disk.PartitionTable{
 		Type: disk.PT_GPT,

pkg/osbuild/mkfs_xfs_stage.go

@@ -1,8 +1,9 @@
 package osbuild
 
 type MkfsXfsStageOptions struct {
-	UUID  string `json:"uuid"`
-	Label string `json:"label,omitempty"`
+	UUID    string `json:"uuid"`
+	Label   string `json:"label,omitempty"`
+	AGCount int    `json:"agcount,omitempty"`
 }
 
 func (MkfsXfsStageOptions) isStageOptions() {}