Struct ReaderCylinderGroup 

#[non_exhaustive]
pub struct ReaderCylinderGroup {
    pub cgx: u32,
    pub ndblk: u32,
    pub niblk: i32,
    pub initediblk: u32,
    pub iusedoff: u32,
    pub freeoff: u32,
    pub clusteroff: u32,
}

Parsed cylinder-group header — the per-group allocation map.

Carries the subset of struct cg P1 needs; #[non_exhaustive] so later phases add fields without a breaking change. The bitmaps themselves are not copied here — Self::inosused_off / Self::blksfree_off give the byte offsets into the header buffer where they live.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

cgx: u32

cg_cgx — this cylinder group’s index.

ndblk: u32

cg_ndblk — number of data blocks in this cylinder group.

niblk: i32

cg_niblk — number of inode blocks in this cylinder group.

initediblk: u32

cg_initediblk — number of initialized inodes in this cg (UFS2).

iusedoff: u32

cg_iusedoff — byte offset (from the header start) of the used-inode bitmap (cg_inosused).

freeoff: u32

cg_freeoff — byte offset (from the header start) of the free-block bitmap (cg_blksfree).

clusteroff: u32

cg_clusteroff — byte offset of the free-cluster bitmap.

Implementations

impl CylinderGroup

pub fn parse(data: &[u8], endian: Endian) -> Result<CylinderGroup, UfsError>

Parse a cylinder-group header from the start of data (i.e. data begins at the struct cg header), using the byte order resolved from the superblock.

Errors

• UfsError::Truncated if data is shorter than the header fields.
• UfsError::BadCgMagic if cg_magic (offset 4) is not 0x00090255 in the given byte order — the offending value is carried.

pub fn inosused_off(&self) -> usize

Byte offset (from the header start) of the used-inode bitmap.

pub fn blksfree_off(&self) -> usize

Byte offset (from the header start) of the free-block bitmap.

Trait Implementations

impl Clone for CylinderGroup

fn clone(&self) -> CylinderGroup

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for CylinderGroup

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

Formats the value using the given formatter.

impl Eq for CylinderGroup

impl PartialEq for CylinderGroup

fn eq(&self, other: &CylinderGroup) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for CylinderGroup