Struct PersistedStateHeader

#[repr(C)]
pub struct PersistedStateHeader {
    pub magic: u64,
    pub protobuf_base: u64,
    pub protobuf_region_len: u64,
    pub protobuf_payload_len: u64,
}

This is the header used to describe the overall persisted state region. By convention, the header resides at the start of VTL2 memory, taking a single page.

This header should never change, instead for new information to be stored add it to the protobuf payload described below.

Fields

magic: u64

A magic value. If this is not set to PersistedStateHeader::MAGIC, then the previous instance did not support this region.

protobuf_base: u64

The gpa for the start of the protobuf region. This must be 4K aligned.

protobuf_region_len: u64

The size of the protobuf region in bytes.

protobuf_payload_len: u64

The size of the protobuf payload in bytes. This must be less than or equal to protobuf_region_len.

Implementations

impl PersistedStateHeader

pub const MAGIC: u64 = 5_927_942_519_240_476_751u64

“OHCLPHDR” in ASCII.

Trait Implementations

impl Debug for PersistedStateHeader

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

Formats the value using the given formatter.

impl FromBytes for PersistedStateHeader

where u64: FromBytes,

fn ref_from_bytes( source: &[u8], ) -> Result<&Self, ConvertError<AlignmentError<&[u8], Self>, SizeError<&[u8], Self>, Infallible>>

where Self: KnownLayout + Immutable,

Interprets the given source as a &Self.

fn ref_from_prefix( source: &[u8], ) -> Result<(&Self, &[u8]), ConvertError<AlignmentError<&[u8], Self>, SizeError<&[u8], Self>, Infallible>>

where Self: KnownLayout + Immutable,

Interprets the prefix of the given source as a &Self without copying.

fn ref_from_suffix( source: &[u8], ) -> Result<(&[u8], &Self), ConvertError<AlignmentError<&[u8], Self>, SizeError<&[u8], Self>, Infallible>>

where Self: Immutable + KnownLayout,

Interprets the suffix of the given bytes as a &Self.

fn mut_from_bytes( source: &mut [u8], ) -> Result<&mut Self, ConvertError<AlignmentError<&mut [u8], Self>, SizeError<&mut [u8], Self>, Infallible>>

where Self: IntoBytes + KnownLayout,

Interprets the given source as a &mut Self.

fn mut_from_prefix( source: &mut [u8], ) -> Result<(&mut Self, &mut [u8]), ConvertError<AlignmentError<&mut [u8], Self>, SizeError<&mut [u8], Self>, Infallible>>

where Self: IntoBytes + KnownLayout,

Interprets the prefix of the given source as a &mut Self without copying.

fn mut_from_suffix( source: &mut [u8], ) -> Result<(&mut [u8], &mut Self), ConvertError<AlignmentError<&mut [u8], Self>, SizeError<&mut [u8], Self>, Infallible>>

where Self: IntoBytes + KnownLayout,

Interprets the suffix of the given source as a &mut Self without copying.

fn ref_from_bytes_with_elems( source: &[u8], count: usize, ) -> Result<&Self, ConvertError<AlignmentError<&[u8], Self>, SizeError<&[u8], Self>, Infallible>>

where Self: KnownLayout<PointerMetadata = usize> + Immutable,

Interprets the given source as a &Self with a DST length equal to count.

fn ref_from_prefix_with_elems( source: &[u8], count: usize, ) -> Result<(&Self, &[u8]), ConvertError<AlignmentError<&[u8], Self>, SizeError<&[u8], Self>, Infallible>>

where Self: KnownLayout<PointerMetadata = usize> + Immutable,

Interprets the prefix of the given source as a DST &Self with length equal to count.

fn ref_from_suffix_with_elems( source: &[u8], count: usize, ) -> Result<(&[u8], &Self), ConvertError<AlignmentError<&[u8], Self>, SizeError<&[u8], Self>, Infallible>>

where Self: KnownLayout<PointerMetadata = usize> + Immutable,

Interprets the suffix of the given source as a DST &Self with length equal to count.

fn mut_from_bytes_with_elems( source: &mut [u8], count: usize, ) -> Result<&mut Self, ConvertError<AlignmentError<&mut [u8], Self>, SizeError<&mut [u8], Self>, Infallible>>

where Self: IntoBytes + KnownLayout<PointerMetadata = usize> + Immutable,

Interprets the given source as a &mut Self with a DST length equal to count.

fn mut_from_prefix_with_elems( source: &mut [u8], count: usize, ) -> Result<(&mut Self, &mut [u8]), ConvertError<AlignmentError<&mut [u8], Self>, SizeError<&mut [u8], Self>, Infallible>>

where Self: IntoBytes + KnownLayout<PointerMetadata = usize>,

Interprets the prefix of the given source as a &mut Self with DST length equal to count.

fn mut_from_suffix_with_elems( source: &mut [u8], count: usize, ) -> Result<(&mut [u8], &mut Self), ConvertError<AlignmentError<&mut [u8], Self>, SizeError<&mut [u8], Self>, Infallible>>

where Self: IntoBytes + KnownLayout<PointerMetadata = usize>,

Interprets the suffix of the given source as a &mut Self with DST length equal to count.

fn read_from_bytes(source: &[u8]) -> Result<Self, SizeError<&[u8], Self>>

where Self: Sized,

Reads a copy of Self from the given source.

fn read_from_prefix( source: &[u8], ) -> Result<(Self, &[u8]), SizeError<&[u8], Self>>

where Self: Sized,

Reads a copy of Self from the prefix of the given source.

fn read_from_suffix( source: &[u8], ) -> Result<(&[u8], Self), SizeError<&[u8], Self>>

where Self: Sized,

Reads a copy of Self from the suffix of the given source.

impl FromZeros for PersistedStateHeader

where u64: FromZeros,

fn zero(&mut self)

Overwrites self with zeros.

fn new_zeroed() -> Self

where Self: Sized,

Creates an instance of Self from zeroed bytes.

fn new_box_zeroed() -> Result<Box<Self>, AllocError>

where Self: Sized,

Creates a Box<Self> from zeroed bytes.

fn new_box_zeroed_with_elems(count: usize) -> Result<Box<Self>, AllocError>

where Self: KnownLayout<PointerMetadata = usize>,

Creates a Box<[Self]> (a boxed slice) from zeroed bytes.

fn new_vec_zeroed(len: usize) -> Result<Vec<Self>, AllocError>

where Self: Sized,

Creates a Vec<Self> from zeroed bytes.

fn extend_vec_zeroed( v: &mut Vec<Self>, additional: usize, ) -> Result<(), AllocError>

where Self: Sized,

Extends a Vec<Self> by pushing additional new items onto the end of the vector. The new items are initialized with zeros.

fn insert_vec_zeroed( v: &mut Vec<Self>, position: usize, additional: usize, ) -> Result<(), AllocError>

where Self: Sized,

Inserts additional new items into Vec<Self> at position. The new items are initialized with zeros.

impl IntoBytes for PersistedStateHeader

where u64: IntoBytes, (): PaddingFree<Self, { _ }>,

fn as_bytes(&self) -> &[u8]

where Self: Immutable,

Gets the bytes of this value.

fn as_mut_bytes(&mut self) -> &mut [u8]

where Self: FromBytes,

Gets the bytes of this value mutably.

fn write_to(&self, dst: &mut [u8]) -> Result<(), SizeError<&Self, &mut [u8]>>

where Self: Immutable,

Writes a copy of self to dst.

fn write_to_prefix( &self, dst: &mut [u8], ) -> Result<(), SizeError<&Self, &mut [u8]>>

where Self: Immutable,

Writes a copy of self to the prefix of dst.

fn write_to_suffix( &self, dst: &mut [u8], ) -> Result<(), SizeError<&Self, &mut [u8]>>

where Self: Immutable,

Writes a copy of self to the suffix of dst.

impl KnownLayout for PersistedStateHeader

where u64: KnownLayout,

type PointerMetadata = <u64 as KnownLayout>::PointerMetadata

The type of metadata stored in a pointer to Self.

impl TryFromBytes for PersistedStateHeader

where u64: TryFromBytes,

fn try_ref_from_bytes( source: &[u8], ) -> Result<&Self, ConvertError<AlignmentError<&[u8], Self>, SizeError<&[u8], Self>, ValidityError<&[u8], Self>>>

where Self: KnownLayout + Immutable,

Attempts to interpret the given source as a &Self.

fn try_ref_from_prefix( source: &[u8], ) -> Result<(&Self, &[u8]), ConvertError<AlignmentError<&[u8], Self>, SizeError<&[u8], Self>, ValidityError<&[u8], Self>>>

where Self: KnownLayout + Immutable,

Attempts to interpret the prefix of the given source as a &Self.

fn try_ref_from_suffix( source: &[u8], ) -> Result<(&[u8], &Self), ConvertError<AlignmentError<&[u8], Self>, SizeError<&[u8], Self>, ValidityError<&[u8], Self>>>

where Self: KnownLayout + Immutable,

Attempts to interpret the suffix of the given source as a &Self.

fn try_mut_from_bytes( bytes: &mut [u8], ) -> Result<&mut Self, ConvertError<AlignmentError<&mut [u8], Self>, SizeError<&mut [u8], Self>, ValidityError<&mut [u8], Self>>>

where Self: KnownLayout + IntoBytes,

Attempts to interpret the given source as a &mut Self without copying.

fn try_mut_from_prefix( source: &mut [u8], ) -> Result<(&mut Self, &mut [u8]), ConvertError<AlignmentError<&mut [u8], Self>, SizeError<&mut [u8], Self>, ValidityError<&mut [u8], Self>>>

where Self: KnownLayout + IntoBytes,

Attempts to interpret the prefix of the given source as a &mut Self.

fn try_mut_from_suffix( source: &mut [u8], ) -> Result<(&mut [u8], &mut Self), ConvertError<AlignmentError<&mut [u8], Self>, SizeError<&mut [u8], Self>, ValidityError<&mut [u8], Self>>>

where Self: KnownLayout + IntoBytes,

Attempts to interpret the suffix of the given source as a &mut Self.

fn try_ref_from_bytes_with_elems( source: &[u8], count: usize, ) -> Result<&Self, ConvertError<AlignmentError<&[u8], Self>, SizeError<&[u8], Self>, ValidityError<&[u8], Self>>>

where Self: KnownLayout<PointerMetadata = usize> + Immutable,

Attempts to interpret the given source as a &Self with a DST length equal to count.

fn try_ref_from_prefix_with_elems( source: &[u8], count: usize, ) -> Result<(&Self, &[u8]), ConvertError<AlignmentError<&[u8], Self>, SizeError<&[u8], Self>, ValidityError<&[u8], Self>>>

where Self: KnownLayout<PointerMetadata = usize> + Immutable,

Attempts to interpret the prefix of the given source as a &Self with a DST length equal to count.

fn try_ref_from_suffix_with_elems( source: &[u8], count: usize, ) -> Result<(&[u8], &Self), ConvertError<AlignmentError<&[u8], Self>, SizeError<&[u8], Self>, ValidityError<&[u8], Self>>>

where Self: KnownLayout<PointerMetadata = usize> + Immutable,

Attempts to interpret the suffix of the given source as a &Self with a DST length equal to count.

fn try_mut_from_bytes_with_elems( source: &mut [u8], count: usize, ) -> Result<&mut Self, ConvertError<AlignmentError<&mut [u8], Self>, SizeError<&mut [u8], Self>, ValidityError<&mut [u8], Self>>>

where Self: KnownLayout<PointerMetadata = usize> + IntoBytes,

Attempts to interpret the given source as a &mut Self with a DST length equal to count.

fn try_mut_from_prefix_with_elems( source: &mut [u8], count: usize, ) -> Result<(&mut Self, &mut [u8]), ConvertError<AlignmentError<&mut [u8], Self>, SizeError<&mut [u8], Self>, ValidityError<&mut [u8], Self>>>

where Self: KnownLayout<PointerMetadata = usize> + IntoBytes,

Attempts to interpret the prefix of the given source as a &mut Self with a DST length equal to count.

fn try_mut_from_suffix_with_elems( source: &mut [u8], count: usize, ) -> Result<(&mut [u8], &mut Self), ConvertError<AlignmentError<&mut [u8], Self>, SizeError<&mut [u8], Self>, ValidityError<&mut [u8], Self>>>

where Self: KnownLayout<PointerMetadata = usize> + IntoBytes,

Attempts to interpret the suffix of the given source as a &mut Self with a DST length equal to count.

fn try_read_from_bytes( source: &[u8], ) -> Result<Self, ConvertError<Infallible, SizeError<&[u8], Self>, ValidityError<&[u8], Self>>>

where Self: Sized,

Attempts to read the given source as a Self.

fn try_read_from_prefix( source: &[u8], ) -> Result<(Self, &[u8]), ConvertError<Infallible, SizeError<&[u8], Self>, ValidityError<&[u8], Self>>>

where Self: Sized,

Attempts to read a Self from the prefix of the given source.

fn try_read_from_suffix( source: &[u8], ) -> Result<(&[u8], Self), ConvertError<Infallible, SizeError<&[u8], Self>, ValidityError<&[u8], Self>>>

where Self: Sized,

Attempts to read a Self from the suffix of the given source.

impl Immutable for PersistedStateHeader

where u64: Immutable,