Partitions
All devices on the Vita are partitioned the same way. Logical block size is 512 bytes and the first logical block is the 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.
Types
typedef struct SceMbrPartEntry { // size is 0x11-bytes
unsigned int start_lba;
unsigned int n_sectors;
unsigned char id;
unsigned char type;
unsigned char flag;
unsigned short acl;
unsigned int unused;
} __attribute__((packed)) SceMbrPartEntry;
typedef struct SceMbrParts { // size is 0x110-bytes
SceMbrPartEntry entries[0x10];
} __attribute__((packed)) SceMbrParts;
typedef struct SceMbr { // size is 0x200-bytes
char magic[0x20];
unsigned int version;
unsigned int n_sectors;
uint64_t unused;
unsigned int loader_start;
unsigned int loader_count;
unsigned int current_bl_lba;
unsigned int bl_bank0_lba;
unsigned int bl_bank1_lba;
unsigned int current_os_lba;
uint64_t unused2;
SceMbrParts parts;
char unused3[0x6E]
char unused4[0x30];
unsigned short signature;
} __attribute__((packed)) SceMbr;Master Block
The first block (512 bytes) provides a partition table as well as auxiliary information to the block management drivers.
| Offset | Size | Information |
|---|---|---|
| 0x0 | 0x20 | magic. Magic string "Sony Computer Entertainment Inc."
|
| 0x20 | 0x4 | version. Usually 3. |
| 0x24 | 0x4 | n_sectors. Size of device in blocks (ex: 0x70A000, 0x71A000: bigger ur0:) |
| 0x28 | 0x8 | unused. |
| 0x30 | 0x4 | loader_start. Second Loader (second_loader.enp) offset in blocks |
| 0x34 | 0x4 | loader_count. Second Loader (second_loader.enp) size in blocks |
| 0x38 | 0x4 | current_bl_lba. Active SLB2 offset in blocks (must be either bank0 or bank1) |
| 0x3C | 0x4 | bl_bank0_lba. SLB2 bank0 offset in blocks (default: 0x4000) |
| 0x40 | 0x4 | bl_bank1_lba. SLB2 bank1 offset in blocks (default: 0x6000) |
| 0x44 | 0x4 | current_os_lba. Active os0 offset in blocks (ex: 0x8000, 0x10000) |
| 0x48 | 0x8 | unused. |
| 0x50 | 0x110 (0x11 per partition * 0x10 partitions) | partition_table. Partition entries (there are 0x10 partitions at most (derived from code and data structure of SdStor driver)) |
| 0x160 | 0x9E | unused. |
| 0x1FE | 0x2 | signature. MBR signature: 0xAA55 |
Partition Entries
Each partition entry is 17 bytes long.
| Offset | Size | Information |
|---|---|---|
| 0x0 | 0x4 | start_lba. Partition offset (blocks) |
| 0x4 | 0x4 | n_sectors. Partition size (blocks) |
| 0x8 | 0x1 | part_id. Partition ID |
| 0x9 | 0x1 | part_type. Partition Type |
| 0xA | 0x1 | part_flag. Partition Flag (boolean) |
| 0xB | 0x2 | acl. Access control lists. Seen: 0x0555, 0x0F0F (sloader, os, vsh) -> r--, 0x0F1F (idstor) -> ---, 0x0F4F, 0x0FFF (sysdata, vtrm, vshdata, updater, pidata, user) -> rwx
|
| 0xF | 0x4 | unused |
Partition ID
The Partition ID uniquely identifies the partition to its function. It is related to SceKernelModulemgr#Partition ID.
| Partition ID | Block Device | Name | Location Seen | Description |
|---|---|---|---|---|
| 0x0 | empty partition | |||
| 0x1 | "idstor" | Internal | IdStorage | |
| 0x2 | "sloader" | Internal | SLB2 Boot loaders | |
| 0x3 | "os" | os0 | Internal | Main OS partition, contains kernel modules |
| 0x4 | "vsh" | vs0 | Internal | System applications & libraries |
| 0x5 | "vshdata" | vd0 | Internal | Registry and error history |
| 0x6 | "vtrm" | tm0 | Internal | NpDrm, Marlin and DevKit/TestKit activations files |
| 0x7 | "user" | ur0 | Internal | User resources, LiveArea cache, database, & other stuff |
| 0x8 | "userext" | ux0 | Internal / Memory Card | Memory Card |
| 0x9 | "gamero" | gro0 | Game Card | Game Card read-only area |
| 0xA | "gamerw" | grw0 | Game Card | Game Card writable area |
| 0xB | "updater" | ud0 | Internal | Updater application and PUP copied here before reboot |
| 0xC | "sysdata" | sa0 | Internal | Dictionary and font data |
| 0xD | "mediaid" | External | Some data on Memory Card & Game Card | |
| 0xE | "pidata" | pd0 | Internal | Welcome Park and welcome video (Partition not present in Prototype units) |
| 0xF | "unused" | External | Unknown |
Partition Type
The partition type indicates the file system or if there is no file system (for example, in the case of a SLB2 archive).
| Partition Type | Name |
|---|---|
| 0x6 | FAT16 |
| 0x7 | exFAT |
| 0xDA | Raw data |
Partition Flag
Some partitions (specifically os0 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.