74
edits
Changes
Jump to navigation
Jump to search
Line 578:
Line 578: + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
Remap Storage
|
|
| End
| End
|}
== Remap Storage ==
Remap Storage is used to remap segments of data from virtual offsets to physical offsets. This allows extending the save file without having to relocate existing data.
Each Remap Storage has three components: [[#Remap storage header|a header]], a remapping table, and the main data storage.
A remap storage can contain a varying number of segments, each representing a chunk of contiguous virtual storage. A segment can be composed of one or more entries. Each of these entries are mapped from their virtual locations to their physical locations by entries in the remapping table. A physical offset corresponds to that offset in the main data storage.
When a segment is extended a new remapping entry is appended to the end of the physical storage, allowing expansion without relocating the existing entries.
Each virtual offset has two parts, a segment index and an offset. The size of these sections is controlled by the remap header.
Example: 0x3000000000000100<br />
If 4 bits were reserved for the segment index, the offset would be split like this, representing offset 0x100 of segment 3.<br />
Segment index: 0x3 Offset: 0x000000000000100
=== Remapping Entry ===
{| class="wikitable"
|-
! Start
! Length
! Description
|-
| 0x00
| 8
| Virtual offset
|-
| 0x08
| 8
| Physical offset
|-
| 0x10
| 8
| Size
|-
| 0x18
| 4
| Alignment
|-
| 0x1c
| 4
| Padding?
|-
|}
|}