Struct GlobalDescriptorTable

#[repr(C, align(16))]
pub struct GlobalDescriptorTable<const N: usize>(pub [Descriptor; N]);

Abstracts the GDT that, primarily, contains descriptors to memory segments.

The GDT is a table that primarily contains segment descriptors. Segment descriptors has a size of 8 Bytes and contains the size, position, access rights, and purpose of such a segment. Unlike the LDT, the GDT is shared between all processes and may contain TSS and LDT descriptors. For the kernel, the first entry is required to be a null descriptor and the code and data segments. To support user-mode processes, additional TSS, code, and data segments for ring 3 must be added.

The base address and size of the GDT are written to the GDTR register during boot (via. lgdt).

• ISDMv3, 2.4.1; Global Descriptor Table Register (GDTR)
• ISDMv3, 3.5.1; Segment Descriptor Tables

Tuple Fields

0: [Descriptor; N]

Implementations

impl<const N: usize> GlobalDescriptorTable<N>

pub const fn pointer(&self) -> DescriptorTablePointer

pub fn activate(&'static self)

Load/activate the GDT

pub const fn selector(&self, idx: usize, user: bool) -> SegmentSelector

Trait Implementations

impl<const N: usize> Clone for GlobalDescriptorTable<N>

fn clone(&self) -> GlobalDescriptorTable<N>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<const N: usize> Debug for GlobalDescriptorTable<N>

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

Formats the value using the given formatter.