51 lines
1.1 KiB
Rust
51 lines
1.1 KiB
Rust
// SPDX-License-Identifier: MPL-2.0
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use core::mem::size_of;
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use crate::{
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mm::{FrameAllocOptions, Segment, VmIo, PAGE_SIZE},
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prelude::Paddr,
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};
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pub struct Queue {
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segment: Segment<()>,
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queue_size: usize,
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tail: usize,
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}
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impl Queue {
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pub fn append_descriptor(&mut self, descriptor: u128) {
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if self.tail == self.queue_size {
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self.tail = 0;
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}
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self.segment
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.write_val(self.tail * size_of::<u128>(), &descriptor)
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.unwrap();
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self.tail += 1;
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}
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pub fn tail(&self) -> usize {
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self.tail
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}
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pub fn size(&self) -> usize {
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self.queue_size
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}
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pub(crate) fn base_paddr(&self) -> Paddr {
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self.segment.start_paddr()
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}
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pub(super) fn new() -> Self {
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const DEFAULT_PAGES: usize = 1;
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let segment = FrameAllocOptions::new()
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.alloc_segment(DEFAULT_PAGES)
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.unwrap();
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Self {
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segment,
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queue_size: (DEFAULT_PAGES * PAGE_SIZE) / size_of::<u128>(),
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tail: 0,
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}
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}
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}
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