From a59d96deae7aa75eaa3c92fbf4fe4ecfcae2d5a4 Mon Sep 17 00:00:00 2001
From: Mateus Melchiades <matbme@duck.com>
Date: Wed, 20 Sep 2023 18:36:37 -0300
Subject: [PATCH] LVM thin pool commands

---
 RECIPE.md       | 21 ++++++++++++++++++++-
 core/lvm/lv.go  | 19 +++++++++++++++++++
 core/lvm/lvm.go | 33 +++++++++++++++++++++++++++++++++
 core/recipe.go  | 37 ++++++++++++++++++++++++++++++++++++-
 4 files changed, 108 insertions(+), 2 deletions(-)

diff --git a/RECIPE.md b/RECIPE.md
index 519b6558..740f05db 100644
--- a/RECIPE.md
+++ b/RECIPE.md
@@ -145,7 +145,7 @@ Create LVM logical volume.
 - *Name* (`string`): Logical volume name.
 - *VG* (`string`): Volume group name.
 - *Type* (`string`): Logical volume type. See lvcreate(8) for available types.
-- *Size* (`float`): Volume group size in MiB.
+- *Size* (`float`): Logical volume size in MiB.
 
 ### lvrename
 
@@ -163,6 +163,25 @@ Deletes LVM logical volume.
 **Accepts**:
 - *Name* (`string`): The logical volume name.
 
+### make-thin-pool
+
+Creates a new LVM thin pool from two LVs: one for metadata and another one for the data itself.
+
+**Accepts**:
+- *Name* (`string`): The created thin pool name.
+- *ThinDataLV* (`string`): The LV for storing data.
+- *ThinMetaLV* (`string`): The LV for storing pool metadata.
+
+### lvcreate-thin
+
+Same as `lvcreate`, but creates a thin LV instead.
+
+**Accepts**:
+- *Name* (`string`): Thin logical volume name.
+- *VG* (`string`): Volume group name.
+- *Size* (`float`): Volume group size in MiB.
+- *Thinpool* (`string`): Name of the thin pool to create the LV from.
+
 --- 
 
 ## Post-Installation 
diff --git a/core/lvm/lv.go b/core/lvm/lv.go
index ba637a1a..fc8d0887 100644
--- a/core/lvm/lv.go
+++ b/core/lvm/lv.go
@@ -282,6 +282,25 @@ func FindLv(vgName, lvName string) (Lv, error) {
 	return lvs[0], nil
 }
 
+func MakeThinPool(poolMetadata, pool interface{}) error {
+	poolMetadataName, err := extractNameFromLv(poolMetadata)
+	if err != nil {
+		return err
+	}
+	poolName, err := extractNameFromLv(pool)
+	if err != nil {
+		return err
+	}
+
+	lvm := NewLvm()
+	_, err = lvm.lvm2Run("lvconvert --type thin-pool --poolmetadata %s %s", poolMetadataName, poolName)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
 func (l *Lv) Rename(newName string) error {
 	lvm := NewLvm()
 	newLv, err := lvm.Lvrename(l.Name, newName, l.VgName)
diff --git a/core/lvm/lvm.go b/core/lvm/lvm.go
index b2a577c4..29d16900 100644
--- a/core/lvm/lvm.go
+++ b/core/lvm/lvm.go
@@ -337,6 +337,25 @@ func (l *Lvm) Lvcreate(name string, vg interface{}, lvType LVType, size float64)
 	return nil
 }
 
+func (l *Lvm) LvThinCreate(name string, vg, pool interface{}, size float64) error {
+	vgName, err := extractNameFromVg(vg)
+	if err != nil {
+		return fmt.Errorf("lvmThinCreate: %v", err)
+	}
+
+	poolName, err := extractNameFromPool(pool)
+	if err != nil {
+		return fmt.Errorf("lvmThinCreate: %v", err)
+	}
+
+	_, err = l.lvm2Run("lvcreate -y -n %s -V %.2fm %s %s", name, size, poolName, vgName)
+	if err != nil {
+		return fmt.Errorf("lvmThinCreate: %v", err)
+	}
+
+	return nil
+}
+
 // lvs (list lvs)
 func (l *Lvm) Lvs(filter ...string) ([]Lv, error) {
 	filterStr := ""
@@ -480,3 +499,17 @@ func extractNameFromLv(lv interface{}) (string, error) {
 
 	return lvName, nil
 }
+
+func extractNameFromPool(pool interface{}) (string, error) {
+	var poolName string
+	switch lvar := pool.(type) {
+	case string:
+		poolName = lvar
+	case *Lv:
+		poolName = lvar.Name
+	default:
+		return "", errors.New("invalid type for pool. Must be either a string with the pool's name or a pointer to a LV struct")
+	}
+
+	return poolName, nil
+}
diff --git a/core/recipe.go b/core/recipe.go
index 89b88e00..7c62dae3 100644
--- a/core/recipe.go
+++ b/core/recipe.go
@@ -450,7 +450,7 @@ func runSetupOperation(diskLabel, operation string, args []interface{}) error {
 	 * - *Name* (`string`): Logical volume name.
 	 * - *VG* (`string`): Volume group name.
 	 * - *Type* (`string`): Logical volume type. See lvcreate(8) for available types.
-	 * - *Size* (`float`): Volume group size in MiB.
+	 * - *Size* (`float`): Logical volume size in MiB.
 	 */
 	case "lvcreate":
 		name := args[0].(string)
@@ -491,6 +491,41 @@ func runSetupOperation(diskLabel, operation string, args []interface{}) error {
 		if err != nil {
 			return err
 		}
+	/* !! ### make-thin-pool
+	 *
+	 * Creates a new LVM thin pool from two LVs: one for metadata and another one for the data itself.
+	 *
+	 * **Accepts**:
+	 * - *Name* (`string`): The created thin pool name.
+	 * - *ThinDataLV* (`string`): The LV for storing data.
+	 * - *ThinMetaLV* (`string`): The LV for storing pool metadata.
+	 */
+	case "make-thin-pool":
+		thinDataLV := args[0].(string)
+		thinMetaLV := args[1].(string)
+		err := lvm.MakeThinPool(thinMetaLV, thinDataLV)
+		if err != nil {
+			return err
+		}
+	/* !! ### lvcreate-thin
+	 *
+	 * Same as `lvcreate`, but creates a thin LV instead.
+	 *
+	 * **Accepts**:
+	 * - *Name* (`string`): Thin logical volume name.
+	 * - *VG* (`string`): Volume group name.
+	 * - *Size* (`float`): Volume group size in MiB.
+	 * - *Thinpool* (`string`): Name of the thin pool to create the LV from.
+	 */
+	case "lvcreate-thin":
+		name := args[0].(string)
+		vg := args[1].(string)
+		vgSize := args[2].(float64)
+		thinPool := args[3].(string)
+		err := LvmInstance.LvThinCreate(name, vg, thinPool, vgSize)
+		if err != nil {
+			return err
+		}
 	/* !! --- */
 	default:
 		return fmt.Errorf("unrecognized operation %s", operation)