Editing Partitions

All devices on the Vita are partitioned the same way. Logical block size is 512 bytes and the first logical block is the [[Partitions#Master Block|master block]] which defines the partition table along with other information. Because of block level encryption, the master block is also encrypted along with everything else and cannot be seen if the device is dumped from an external dumper.

== Master Block ==
The first block (512 bytes) provides a partition table as well as auxiliary information to the block management drivers.
{| class="wikitable"
|-
! Offset
! Size
! Information
|-
| 0x0
| 0x20
| Magic string "<code>Sony Computer Entertainment Inc.</code>"
|-
| 0x20
| 0x4
| Version ? (0x3)
|-
| 0x24
| 0x4
| Size of device in blocks
|-
| 0x28
| 0x28
| ?
|-
| 0x50
| 0x11 - 0x110
| [[Partitions#Partition Entries|Partition entries]] (there are 0x10 partitions at most (derived from code and data structure of SdStor driver))
|-
| 0x160
| 0x5E
| unknown (zeros)
|-
| 0x1BE
| 0x10
| unknown (may contain some data) (In standard MBR this area corresponds to Partition Entry)
|-
| 0x1CE
| 0x10
| unknown (must contain zeros) (In standard MBR this area corresponds to Partition Entry)
|-
| 0x1DE
| 0x10
| unknown (must contain zeros) (In standard MBR this area corresponds to Partition Entry)
|-
| 0x1EE
| 0x10
| unknown (must contain zeros) (In standard MBR this area corresponds to Partition Entry)
|-
| 0x1FE
| 0x2
| 0xAA55 signature
|}

== Partition Entries ==
Each partition entry is 17 bytes long. Offset 0x0 means end of table.
{| class="wikitable"
|-
! Offset
! Size
! Information
|-
| 0x0
| 0x4
| Partition offset (blocks)
|-
| 0x4
| 0x4
| Partition size (blocks)
|-
| 0x8
| 0x1
| [[Partitions#Partition Code|Partition code]]
|-
| 0x9
| 0x1
| [[Partitions#Partition Type|Partition type]]
|-
| 0xA
| 0x1
| [[Partitions#Partition Active|Partition active]]
|-
| 0xB
| 0x4
| Flags ? seen: <code>0x00000F1F</code>, <code>0x00000F0F</code>, <code>0x00000FFF</code>, <code>0x??????55</code>, <code>0x00000F4F</code>
|-
| 0xF
| 0x2
| ?
|}
=== Partition Code ===
The partition code uniquely identifies the partition to its function.

It is related to [[SceKernelModulemgr#Partition Code]] but the meaning of the code is still unknown.

{| class="wikitable"
! Name
! PartitionSize
! Code
! Type
! Physical
! Description
|-
| 
| 
| 0x0
| raw
| [[EMMC]]
| empty partition
|-
| 
| 
| 0x1
| raw
| [[EMMC]]
| first eMMC partition, some data [[IdStorage]]?
|-
| 
| 
| 0x2
| raw
| [[EMMC]]
| [[SLB2]] [[Boot Sequence|Boot loaders]]
|-
| [[Files_on_the_PS_Vita#os0|os0]]
| 15.96MB
| 0x3
| [https://en.wikipedia.org/wiki/File_Allocation_Table#FAT16 FAT16]
| [[EMMC]]
| The “main” OS files. Includes all the [[kernel libraries]] and the most important [[user libraries]]. There is always two copies of this for redundancy and updating will only update the inactive partition and the active flag is swapped.
|-
| [[Files_on_the_PS_Vita#pd0|pd0]]
| 303.91 MB
| 0xE
| [https://en.wikipedia.org/wiki/ExFAT exFAT]
| [[EMMC]]
| [[Welcome Park]] and [[Intro Video]]. It is also the “preinst” PUP update.
|-
| [[Files_on_the_PS_Vita#sa0|sa0]]
| 95.95 MB
| 0xC
| [https://en.wikipedia.org/wiki/File_Allocation_Table#FAT16 FAT16]
| [[EMMC]]
| The “bulky” data like fonts and handwriting information. Why is it a separate partition? Because it makes updates smaller. Your “systemdata” PUP provides the update for this partition.
|-
| [[Files_on_the_PS_Vita#sd0|sd0]]
| 
| 
| [https://en.wikipedia.org/wiki/File_Allocation_Table#FAT16 FAT16]
| 
| Unique to DEVKITs? (Needs confirmation on this). Used for sdcard storage (updates).
|-
| [[Files_on_the_PS_Vita#tm0|tm0]]
| 31.95 MB
| 0x6
| [https://en.wikipedia.org/wiki/File_Allocation_Table#FAT16 FAT16]
| [[EMMC]]
| eMMC-NAND npdrm partition.
|-
| [[Files_on_the_PS_Vita#ud0|ud0]]
| 255.91 MB
| 0xB
| [https://en.wikipedia.org/wiki/File_Allocation_Table#FAT16 FAT16]
| [[EMMC]]
| When you update the Vita, the update file is copied here and the system reboots.
|-
| [[Files_on_the_PS_Vita#ur0|ur0]]
| 2.55 GB
| 0x7
| [https://en.wikipedia.org/wiki/ExFAT exFAT]
| [[EMMC]]
| NAND is the remaining user data that is structured similarly to the memory card (it shares almost the same directory structure). App icon layout for example is found here.
|-
| [[Files_on_the_PS_Vita#ux0|ux0]]
| varies
| 0x8
| [https://en.wikipedia.org/wiki/ExFAT exFAT]
| [[Memory_Card]]
| User Storage, commonly used for homebrew
|-
| [[Files_on_the_PS_Vita#vd0|vd0]]
| 31.95 MB
| 0x5
| [https://en.wikipedia.org/wiki/File_Allocation_Table#FAT16 FAT16]
| [[EMMC]]
| [[Registry]] and [[error history]]
|-
| [[Files_on_the_PS_Vita#vs0|vs0]]
| 255.73 MB
| 0x4
| [https://en.wikipedia.org/wiki/File_Allocation_Table#FAT16 FAT16]
| [[EMMC]]
| Rest of the OS including all the system apps, the main shell, and the remaining user libraries.
|-
| gro0
| varies
| 0x9
| 
| [[Game_Card]]
| Read-Only partition of the Game Card
|-
| grw0
| varies
| 0xA
| 
| [[Game_Card]]
| Read-Write partition of the game card if supported (for storing save games, patches and DLC of the game to cartridge).
|}

=== Partition Type ===
The partition type code indicates the file system used or if there is no file system (for example, in the case of a [[SLB2]] archive).
{| class="wikitable"
|-
! Code
! Description
|-
| 0x6
| FAT16
|-
| 0x7
| exFAT
|-
| 0xDA
| Raw data
|}

=== Partition Active ===
Some partitions (specifically <code>os0</code> and the boot loaders) have a shadow redundant copy. On update, only the inactive partition is written to and finally the active partition is swapped. For partitions that do not use this feature, this value is ignored.