Ansible-Bootstrap/roles/partitioning/tasks/_create_lvm.yml

---
# LVM Sizing Algorithm
# ====================
# Sizes are computed from disk_size_gb, memory_mb, and feature flags.
#
# Swap sizing:
#   - RAM >= 16 GB → swap = RAM/2 (in GB)
#   - RAM <  16 GB → swap = max(RAM_GB, 2)
#   - Capped to: min(target, 4 + max(disk - overhead, 0))
#   - Further capped to: max available after subtracting reserved + CIS + extent reserve + 4 GB buffer
#
# Root sizing:
#   - Full-disk mode (default): disk - reserved - swap - extent_reserve - (CIS volumes if enabled)
#   - Partial mode: tiered — <4 GB available → 4 GB, 4-12 GB → all available, >12 GB → 40% of disk
#
# CIS volumes (only when CIS enabled):
#   - /home: max(min(home_raw, home_max), home_min) where home_raw = (disk - overhead) * 10%
#   - /var: 2 GB, /var/log: 2 GB, /var/log/audit: 1.5 GB
#
# Extent reserve: 10 extents * 4 MiB = ~0.04 GB (prevents VG overflow)

- name: Create LVM logical volumes
  when: system_cfg.filesystem != 'btrfs'
  block:
    - name: Create LVM volume group
      community.general.lvg:
        vg: "{{ partitioning_vg_name }}"
        pvs: "{{ partitioning_root_device }}"

    - name: Create LVM logical volumes
      when:
        - system_cfg.features.cis.enabled | bool or item.lv not in ['home', 'var', 'var_log', 'var_log_audit']
        - system_cfg.features.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: >-
          {{
            (
              ((partitioning_memory_mb | float / 1024) >= 16.0)
              | ternary(
                  (partitioning_memory_mb | float / 2048),
                  [(partitioning_memory_mb | float / 1024), 2] | max | float
                )
            )
            if system_cfg.features.swap.enabled | bool
            else 0
          }}
        partitioning_lvm_swap_cap_gb: >-
          {{
            (
              4
              + [
                (partitioning_disk_size_gb | float) - (partitioning_disk_overhead_gb | float),
                0
              ] | max
            )
            if system_cfg.features.swap.enabled | bool
            else 0
          }}
        partitioning_lvm_swap_target_limited_gb: >-
          {{
            (
              [
                partitioning_lvm_swap_target_gb,
                partitioning_lvm_swap_cap_gb
              ] | min
            )
            if system_cfg.features.swap.enabled | bool
            else 0
          }}
        partitioning_lvm_swap_max_gb: >-
          {{
            (
              [
                (
                  (partitioning_disk_size_gb | float)
                  - (partitioning_reserved_gb | float)
                  - (system_cfg.features.cis.enabled | bool | ternary(partitioning_cis_reserved_gb | float, 0))
                  - partitioning_lvm_extent_reserve_gb
                  - 4
                ),
                0
              ] | max
            )
            if system_cfg.features.swap.enabled | bool
            else 0
          }}
        partitioning_lvm_available_gb: >-
          {{
            (
              (partitioning_disk_size_gb | float)
              - (partitioning_reserved_gb | float)
              - (system_cfg.features.cis.enabled | bool | ternary(partitioning_cis_reserved_gb | float, 0))
              - partitioning_lvm_extent_reserve_gb
              - partitioning_lvm_swap_target_limited_gb
            ) | float
          }}
        partitioning_lvm_home_raw_gb: >-
          {{
            ((partitioning_disk_size_gb | float) - (partitioning_disk_overhead_gb | float))
            * (partitioning_home_allocation_pct | float)
          }}
        partitioning_lvm_home_gb: >-
          {{
            [
              [(partitioning_lvm_home_raw_gb | float), (partitioning_home_min_gb | float)] | max,
              (partitioning_home_max_gb | float)
            ] | min
          }}
        partitioning_lvm_root_default_gb: >-
          {{
            [
              (
                ((partitioning_lvm_available_gb | float) < 4)
                | ternary(
                    4,
                    (
                      ((partitioning_lvm_available_gb | float) > 12)
                      | ternary(
                          ((partitioning_disk_size_gb | float) * 0.4)
                          | round(0, 'ceil'),
                          partitioning_lvm_available_gb
                        )
                    )
                  )
              ),
              4
            ] | max
          }}
        partitioning_lvm_swap_gb: >-
          {{
            (
              [
                partitioning_lvm_swap_target_limited_gb,
                partitioning_lvm_swap_max_gb
              ] | min | round(2, 'floor')
            )
            if system_cfg.features.swap.enabled | bool
            else 0
          }}
        partitioning_lvm_root_full_gb: >-
          {{
            [
              (
                (partitioning_disk_size_gb | float)
                - (partitioning_reserved_gb | float)
                - (partitioning_lvm_swap_gb | float)
                - partitioning_lvm_extent_reserve_gb
                - (
                    (partitioning_lvm_home_gb | float)
                    + (partitioning_lvm_var_gb | float)
                    + (partitioning_lvm_var_log_gb | float)
                    + (partitioning_lvm_var_log_audit_gb | float)
                    if system_cfg.features.cis.enabled | bool
                    else 0
                  )
              ),
              4
            ] | max | round(2, 'floor')
          }}
        partitioning_lvm_root_gb: >-
          {{
            partitioning_lvm_root_full_gb
            if partitioning_use_full_disk | bool
            else partitioning_lvm_root_default_gb
          }}
      community.general.lvol:
        vg: "{{ partitioning_vg_name }}"
        lv: "{{ item.lv }}"
        size: "{{ item.size }}"
        state: present
      loop:
        - lv: root
          size: "{{ partitioning_lvm_root_gb | string + 'G' }}"
        - lv: swap
          size: "{{ partitioning_lvm_swap_gb | string + 'G' }}"
        - lv: home
          size: "{{ partitioning_lvm_home_gb | string + 'G' }}"
        - { lv: var, size: "{{ partitioning_lvm_var_gb }}G" }
        - { lv: var_log, size: "{{ partitioning_lvm_var_log_gb }}G" }
        - { lv: var_log_audit, size: "{{ partitioning_lvm_var_log_audit_gb }}G" }
      loop_control:
        label: "{{ item.lv }}"