Struct Tss 

pub struct Tss {
    tss: UnsafeCell<TaskStateSegment>,
    ist1: AlignedStack<8192>,
    ist2: AlignedStack<8192>,
    ist3: AlignedStack<8192>,
    ist4: AlignedStack<8192>,
}

Owns the TaskStateSegment and its four IST stacks; must not move after Tss::init (the GDT descriptor points to it).

Fields

tss: UnsafeCell<TaskStateSegment>

ist1: AlignedStack<8192>

ist2: AlignedStack<8192>

ist3: AlignedStack<8192>

ist4: AlignedStack<8192>

Implementations

impl Tss

pub const fn new() -> Self

Create a new, uninitialized Tss; call Tss::init to populate it.

pub unsafe fn init(&'static self)

Build the TSS with RSP0 pointing to 0 and the predefined IST stacks

Safety

This method must be called exactly once before Tss::tss is called to avoid undefined behavior and multiple mutable references.

pub unsafe fn tss(&'static self) -> &'static TaskStateSegment

Getter for Tss::tss, returns a reference

Safety

The caller must guarantee that there are no mutable references or pointers to self.tss

pub unsafe fn set_rsp0(&self, new_rsp0: VirtAddr)

Setter for TSS.RSP0

Safety

The caller must guarantee the following:

• That Tss::init has already been called
• This method is only called on the CPU which owns this TSS
• That no refs/ptrs from Tss::tss are held when this is called
• new_rsp0 is a valid pointer to a valid, mapped kernel stack

Trait Implementations

impl Sync for Tss

Safety: tss will only be written to by the owner CPU and will only be written to when the CPU transitions from userspace to kernelspace, where no kernel code could’ve run before