fix(partitioning): add LVM extent headroom

roles/partitioning/tasks/main.yml

@@ -262,6 +262,16 @@
         - cis_enabled or item.lv not in ['home', 'var', 'var_log', 'var_log_audit']
         - swap_enabled | bool or item.lv != 'swap'
       vars:
+        partitioning_lvm_extent_reserve_count: 10
+        partitioning_lvm_extent_size_mib: 4
+        partitioning_lvm_extent_reserve_gb: >-
+          {{
+            (
+              (partitioning_lvm_extent_reserve_count | float)
+              * (partitioning_lvm_extent_size_mib | float)
+              / 1024
+            ) | round(2, 'ceil')
+          }}
         partitioning_lvm_swap_target_gb: >-
           {{
             (
@@ -304,6 +314,7 @@
                   (partitioning_vm_size_effective | float)
                   - (partitioning_reserved_gb | float)
                   - (cis_enabled | ternary(7.5, 0))
+                  - partitioning_lvm_extent_reserve_gb
                   - 4
                 ),
                 0
@@ -318,6 +329,7 @@
               (partitioning_vm_size_effective | float)
               - (partitioning_reserved_gb | float)
               - (cis_enabled | ternary(7.5, 0))
+              - partitioning_lvm_extent_reserve_gb
               - partitioning_lvm_swap_target_effective_gb
             ) | float
           }}
@@ -363,6 +375,7 @@
                 (partitioning_vm_size_effective | float)
                 - (partitioning_reserved_gb | float)
                 - (partitioning_lvm_swap_gb | float)
+                - partitioning_lvm_extent_reserve_gb
                 - (
                     (partitioning_lvm_home_gb | float) + 5.5
                     if cis_enabled