feat: PV resize support

There is an usecase when the physical device size can change (e.g. on
VM). We need to be able to change the size of the LVM PV to accomodate
that. This adds a new pool parameter 'grow_to_fill'. When set, pool PVs
will try to take all available space on their respective devices.
Defaults to False.

Requires blivet version that supports this feature.
For tests this is checked by using 'does_library_support' script.

defaults/main.yml

@@ -13,6 +13,7 @@ storage_pool_defaults:
   type: lvm
   disks: []
   volumes: []
+  grow_to_fill: false
 
   encryption: false
   encryption_password: null

library/blivet.py

@@ -51,6 +51,9 @@
             encryption_password:
                 description: encryption_password
                 type: str
+            grow_to_fill:
+                description: grow_to_fill
+                type: bool
             name:
                 description: name
                 type: str
@@ -370,7 +373,7 @@
     from blivet3.callbacks import callbacks
     from blivet3 import devicelibs
     from blivet3 import devices
-    from blivet3.deviceaction import ActionConfigureFormat, ActionAddMember, ActionRemoveMember
+    from blivet3.deviceaction import ActionConfigureFormat, ActionResizeFormat, ActionAddMember, ActionRemoveMember
     from blivet3.devicefactory import DEFAULT_THPOOL_RESERVE
     from blivet3.flags import flags as blivet_flags
     from blivet3.formats import fslib, get_format
@@ -386,7 +389,7 @@
         from blivet.callbacks import callbacks
         from blivet import devicelibs
         from blivet import devices
-        from blivet.deviceaction import ActionConfigureFormat, ActionAddMember, ActionRemoveMember
+        from blivet.deviceaction import ActionConfigureFormat, ActionResizeFormat, ActionAddMember, ActionRemoveMember
         from blivet.devicefactory import DEFAULT_THPOOL_RESERVE
         from blivet.flags import flags as blivet_flags
         from blivet.formats import fslib, get_format
@@ -412,6 +415,7 @@ def __getattr__(self, val):
     blivet_flags.allow_online_fs_resize = True
     blivet_flags.gfs2 = True
     set_up_logging()
+
     log = logging.getLogger(BLIVET_PACKAGE + ".ansible")
 
     # XXX add support for LVM RAID raid0 level
@@ -1747,6 +1751,18 @@ def _manage_members(self):
         add_disks = [d for d in self._disks if d not in self._device.ancestors]
         remove_disks = [pv for pv in self._device.pvs if not any(d in pv.ancestors for d in self._disks)]
 
+        if self._pool['grow_to_fill']:
+            grow_pv_candidates = [pv for pv in self._device.pvs if pv not in remove_disks and pv not in add_disks]
+
+            for pv in grow_pv_candidates:
+                if abs(self._device.size - self._device.current_size) < 2 * self._device.pe_size:
+                    continue
+
+                pv.format.update_size_info()  # set pv to be resizable
+                pv.grow_to_fill = True
+                ac = ActionResizeFormat(pv, self._device.size)
+                self._blivet.devicetree.actions.add(ac)
+
         if not (add_disks or remove_disks):
             return
 
@@ -2135,6 +2151,7 @@ def run_module():
                                 encryption_key_size=dict(type='int'),
                                 encryption_luks_version=dict(type='str'),
                                 encryption_password=dict(type='str', no_log=True),
+                                grow_to_fill=dict(type='bool'),
                                 name=dict(type='str'),
                                 raid_level=dict(type='str'),
                                 raid_device_count=dict(type='int'),
@@ -2279,6 +2296,7 @@ def action_dict(action):
         # execute the scheduled actions, committing changes to disk
         callbacks.action_executed.add(record_action)
         callbacks.action_executed.add(ensure_udev_update)
+
         try:
             b.devicetree.actions.process(devices=b.devicetree.devices, dry_run=module.check_mode)
         except Exception as e:

tests/test-verify-pool-members.yml

@@ -70,6 +70,25 @@
     loop_var: pv
   when: storage_test_pool.type == 'lvm'
 
+- name: Check that blivet supports PV grow to fill
+  ansible.builtin.script: >-
+    scripts/does_library_support.py
+    blivet.formats.lvmpv.LVMPhysicalVolume.grow_to_fill
+  args:
+    executable: "{{ ansible_python.executable }}"
+  register: grow_supported
+  changed_when: false
+
+- name: Verify that PVs fill the whole devices when they should
+  include_tasks: verify-pool-member-pvsize.yml
+  loop: "{{ _storage_test_pool_pvs | default([]) }}"
+  loop_control:
+    loop_var: st_pool_pv
+  when: 
+  - grow_supported.stdout | trim == 'True'
+  - storage_test_pool.type == "lvm"
+  - storage_test_pool.grow_to_fill | bool
+
 - name: Check MD RAID
   include_tasks: verify-pool-md.yml
 

tests/tests_lvm_pool_pv_grow.yml

@@ -0,0 +1,99 @@
+---
+- name: Test create disk and remove
+  hosts: all
+  become: true
+  vars:
+    storage_safe_mode: false
+    mount_location1: '/opt/test1'
+    mount_location2: '/opt/test2'
+    pv_size: '8g'
+    volume1_size: '2g'
+    volume2_size: '3g'
+  tags:
+    - tests::lvm
+
+  tasks:
+    - name: Run the role
+      include_role:
+        name: linux-system-roles.storage
+
+    - name: Mark tasks to be skipped
+      set_fact:
+        storage_skip_checks:
+          - blivet_available
+          - service_facts
+          - "{{ (lookup('env',
+                        'SYSTEM_ROLES_REMOVE_CLOUD_INIT') in ['', 'false']) |
+                ternary('packages_installed', '') }}"
+
+    - name: Get unused disks
+      include_tasks: get_unused_disk.yml
+      vars:
+        max_return: 1
+
+    - name: Create PV with a space to grow
+      command: "pvcreate --setphysicalvolumesize {{ pv_size }} /dev/{{ unused_disks[0] }}"
+      register: pvcreate_output
+      changed_when: pvcreate_output.rc != 0
+
+      # VG has to be present, the role otherwise automatically reformats empty PV,
+      # taking all available space
+    - name: Create VG
+      command: "vgcreate foo /dev/{{ unused_disks[0] }}"
+      register: vgcreate_output
+      changed_when: vgcreate_output.rc != 0
+
+    - name: Create LVM
+      include_role:
+        name: linux-system-roles.storage
+      vars:
+        storage_pools:
+          - name: foo
+            disks: "{{ unused_disks }}"
+            grow_to_fill: true
+            state: present
+            volumes:
+              - name: test1
+                size: "{{ volume1_size }}"
+                mount_point: "{{ mount_location1 }}"
+              - name: test2
+                size: "{{ volume2_size }}"
+                mount_point: "{{ mount_location2 }}"
+
+    - name: Verify role results
+      include_tasks: verify-role-results.yml
+
+    - name: Rerun the task to verify idempotence
+      include_role:
+        name: linux-system-roles.storage
+      vars:
+        storage_pools:
+          - name: foo
+            disks: "{{ unused_disks }}"
+            grow_to_fill: true
+            state: present
+            volumes:
+              - name: test1
+                size: "{{ volume1_size }}"
+                mount_point: "{{ mount_location1 }}"
+              - name: test2
+                size: "{{ volume2_size }}"
+                mount_point: "{{ mount_location2 }}"
+
+    - name: Verify role results
+      include_tasks: verify-role-results.yml
+
+    - name: Remove 'foo' pool created above
+      include_role:
+        name: linux-system-roles.storage
+      vars:
+        storage_pools:
+          - name: foo
+            disks: "{{ unused_disks }}"
+            state: "absent"
+            volumes:
+              - name: test1
+              - name: test2
+
+    - name: Verify role results
+      include_tasks: verify-role-results.yml

tests/verify-pool-member-pvsize.yml

@@ -0,0 +1,24 @@
+---
+- name: Get actual PV size
+  command: "pvs --noheadings --nosuffix --units b -o SIZE {{ st_pool_pv }}"
+  register: actual_pv_size
+  changed_when: false
+
+- name: Convert blkinfo size to bytes
+  bsize:
+    size: "{{ storage_test_blkinfo.info[st_pool_pv]['size'] }}"
+  register: dev_size
+
+- name: Verify each PV size
+  assert:
+    that: (dev_size.bytes - actual_pv_size.stdout | int) |
+      abs / actual_pv_size.stdout | int < 0.04
+    msg: >-
+      PV resize failure; size difference too big
+      (device size: {{ dev_size.bytes }})
+      (actual PV size: {{ actual_pv_size.stdout }})
+
+- name: Clean up test variables
+  set_fact:
+    actual_pv_size: null
+    dev_size: null