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Minor refactor

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Mark
2025-03-02 10:11:19 -08:00
parent 1db789889c
commit bf202a42ba
6 changed files with 111 additions and 105 deletions
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100
tetros/src/idt/stackframe.rs
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@ -1,105 +1,9 @@
use bitflags::bitflags;
use core::arch::asm;
use core::{fmt, ops::Deref};
use crate::os::EFlags;
use super::VirtAddr;
bitflags! {
/// The EFLAGS register. All bit patterns are valid representations for this type.
///
/// See https://wiki.osdev.org/CPU_Registers_x86#EFLAGS_Register
#[repr(transparent)]
#[derive(PartialEq, Eq, PartialOrd, Ord, Hash, Debug, Clone, Copy)]
pub struct EFlags: u32 {
/// Processor feature identification flag.
///
/// If this flag is modifiable, the CPU supports CPUID.
const ID = 1 << 21;
/// Indicates that an external, maskable interrupt is pending.
///
/// Used when virtual-8086 mode extensions (CR4.VME) or protected-mode virtual
/// interrupts (CR4.PVI) are activated.
const VIRTUAL_INTERRUPT_PENDING = 1 << 20;
/// Virtual image of the INTERRUPT_FLAG bit.
///
/// Used when virtual-8086 mode extensions (CR4.VME) or protected-mode virtual
/// interrupts (CR4.PVI) are activated.
const VIRTUAL_INTERRUPT = 1 << 19;
/// Enable automatic alignment checking if CR0.AM is set. Only works if CPL is 3.
const ALIGNMENT_CHECK = 1 << 18;
/// Enable the virtual-8086 mode.
const VIRTUAL_8086_MODE = 1 << 17;
/// Allows to restart an instruction following an instruction breakpoint.
const RESUME_FLAG = 1 << 16;
/// Used by `iret` in hardware task switch mode to determine if current task is nested.
const NESTED_TASK = 1 << 14;
/// The high bit of the I/O Privilege Level field.
///
/// Specifies the privilege level required for executing I/O address-space instructions.
const IOPL_HIGH = 1 << 13;
/// The low bit of the I/O Privilege Level field.
///
/// Specifies the privilege level required for executing I/O address-space instructions.
const IOPL_LOW = 1 << 12;
/// Set by hardware to indicate that the sign bit of the result of the last signed integer
/// operation differs from the source operands.
const OVERFLOW_FLAG = 1 << 11;
/// Determines the order in which strings are processed.
const DIRECTION_FLAG = 1 << 10;
/// Enable interrupts.
const INTERRUPT_FLAG = 1 << 9;
/// Enable single-step mode for debugging.
const TRAP_FLAG = 1 << 8;
/// Set by hardware if last arithmetic operation resulted in a negative value.
const SIGN_FLAG = 1 << 7;
/// Set by hardware if last arithmetic operation resulted in a zero value.
const ZERO_FLAG = 1 << 6;
/// Set by hardware if last arithmetic operation generated a carry ouf of bit 3 of the
/// result.
const AUXILIARY_CARRY_FLAG = 1 << 4;
/// Set by hardware if last result has an even number of 1 bits (only for some operations).
const PARITY_FLAG = 1 << 2;
/// Set by hardware if last arithmetic operation generated a carry out of the
/// most-significant bit of the result.
const CARRY_FLAG = 1;
}
}
impl EFlags {
#[inline]
pub fn read() -> EFlags {
EFlags::from_bits_truncate(EFlags::read_raw())
}
#[inline]
fn read_raw() -> u32 {
let r: u32;
unsafe {
asm!("pushfd; pop {0:e}", out(reg) r, options(nomem, preserves_flags));
}
r
}
}
/// Wrapper type for the interrupt stack frame pushed by the CPU.
///
/// This type derefs to an [`InterruptStackFrameValue`], which allows reading the actual values.