When the size of a logical volume is not aligned to the extent size of
the volume group, LVM2 will automatically align it by rounding up[1]:
Rounding up size to full physical extent 29.80 GiB
Rounding up size to full physical extent <3.82 GiB
Since we don't take that into account when we create a new volume or
set the size of an existing one, the size for the whole volume group
will be short by that amount and thus the creation of the last volume
will fail:
Volume group <uuid> has insufficient free space (975 extents): 977 required.
To fix this a new `AlignUp` method is added to the `MountpointCreator`
creator interface. It will align a given size to the requirements of
the implementing container, like e.g. `LVMVolumeGroup`. It is then
used by a new `alignEntityBranch` which takes a size and walks the
entity path, calling `AlignUp` for all entities that implement said
`MountpointCreator` interface; thus the resulting size should fullfil
the alignment requirement for all elements in the path.
NB: `PartitionTable` already had an `AlignUp` method.
Add a corresponding test.
[1]: 8686657664/lib/metadata/metadata.c (L1072)
Co-authored-by: Achilleas Koutsou <achilleas@koutsou.net>
This is for all entities that have a uniquely identifiable via a UUID.
Currently the interface only contains a single function, GenUUID(),
that should generate a new UUID via a random source (`rand.Rand`).
NB: Partitions are uniquely identifiable if and only if the layout is
GPT.
Co-Authored-By: Achilleas Koutsou <achilleas@koutsou.net>
All disk.Entitity types now implement Clone() which should return a
deep copy of the same object. Add the Clone() method to the entity
interface. The return type is Entity, but callers can assume it's
safe to convert back to the original type.
Co-Authored-By: Christian Kellner <christian@kellner.me>
Structs to represent a Btrfs file system with subvolumes.
Btrfs implements the following interfaces:
- Entity
- Container
- VolumeContainer
BtrfsSubvolume implements the following interfaces:
- Entity
- Sizeable
- Mountable
Co-Authored-By: Christian Kellner <christian@kellner.me>
