Struct BackupRoot 

pub struct BackupRoot {

    pub tree_root: u64,
    pub tree_root_gen: u64,
    pub chunk_root: u64,
    pub chunk_root_gen: u64,
    pub extent_root: u64,
    pub extent_root_gen: u64,
    pub fs_root: u64,
    pub fs_root_gen: u64,
    pub dev_root: u64,
    pub dev_root_gen: u64,
    pub csum_root: u64,
    pub csum_root_gen: u64,
    pub total_bytes: u64,
    pub bytes_used: u64,
    pub num_devices: u64,
    pub tree_root_level: u8,
    pub chunk_root_level: u8,
    pub extent_root_level: u8,
    pub fs_root_level: u8,
    pub dev_root_level: u8,
    pub csum_root_level: u8,
}

A single backup root entry from the superblock’s super_roots array.

The kernel maintains four rotating backup copies of the critical tree root pointers. On mount failure, these can be used to recover an older consistent state.

Fields

tree_root: u64

Logical bytenr of the root tree root block.

tree_root_gen: u64

Generation of the root tree root.

chunk_root: u64

Logical bytenr of the chunk tree root block.

chunk_root_gen: u64

Generation of the chunk tree root.

extent_root: u64

Logical bytenr of the extent tree root block.

extent_root_gen: u64

Generation of the extent tree root.

fs_root: u64

Logical bytenr of the FS tree root block.

fs_root_gen: u64

Generation of the FS tree root.

dev_root: u64

Logical bytenr of the device tree root block.

dev_root_gen: u64

Generation of the device tree root.

csum_root: u64

Logical bytenr of the checksum tree root block.

csum_root_gen: u64

Generation of the checksum tree root.

total_bytes: u64

Total bytes in the filesystem at backup time.

bytes_used: u64

Bytes used at backup time.

num_devices: u64

Number of devices at backup time.

tree_root_level: u8

B-tree level of the root tree root.

chunk_root_level: u8

B-tree level of the chunk tree root.

extent_root_level: u8

B-tree level of the extent tree root.

fs_root_level: u8

B-tree level of the FS tree root.

dev_root_level: u8

B-tree level of the device tree root.

csum_root_level: u8

B-tree level of the checksum tree root.

Trait Implementations

impl Clone for BackupRoot

fn clone(&self) -> BackupRoot

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for BackupRoot

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for BackupRoot

fn default() -> BackupRoot

Returns the “default value” for a type.