page_table_entry/
lib.rs

1#![cfg_attr(not(test), no_std)]
2#![cfg_attr(doc, feature(doc_auto_cfg))]
3#![doc = include_str!("../README.md")]
4
5mod arch;
6
7use core::fmt::{self, Debug};
8use memory_addr::PhysAddr;
9
10pub use self::arch::*;
11
12bitflags::bitflags! {
13    /// Generic page table entry flags that indicate the corresponding mapped
14    /// memory region permissions and attributes.
15    #[derive(Clone, Copy, PartialEq)]
16    pub struct MappingFlags: usize {
17        /// The memory is readable.
18        const READ          = 1 << 0;
19        /// The memory is writable.
20        const WRITE         = 1 << 1;
21        /// The memory is executable.
22        const EXECUTE       = 1 << 2;
23        /// The memory is user accessible.
24        const USER          = 1 << 3;
25        /// The memory is device memory.
26        const DEVICE        = 1 << 4;
27        /// The memory is uncached.
28        const UNCACHED      = 1 << 5;
29    }
30}
31
32impl Debug for MappingFlags {
33    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
34        Debug::fmt(&self.0, f)
35    }
36}
37
38/// A generic page table entry.
39///
40/// All architecture-specific page table entry types implement this trait.
41pub trait GenericPTE: Debug + Clone + Copy + Sync + Send + Sized {
42    /// Creates a page table entry point to a terminate page or block.
43    fn new_page(paddr: PhysAddr, flags: MappingFlags, is_huge: bool) -> Self;
44    /// Creates a page table entry point to a next level page table.
45    fn new_table(paddr: PhysAddr) -> Self;
46
47    /// Returns the physical address mapped by this entry.
48    fn paddr(&self) -> PhysAddr;
49    /// Returns the flags of this entry.
50    fn flags(&self) -> MappingFlags;
51
52    /// Set mapped physical address of the entry.
53    fn set_paddr(&mut self, paddr: PhysAddr);
54    /// Set flags of the entry.
55    fn set_flags(&mut self, flags: MappingFlags, is_huge: bool);
56
57    /// Returns the raw bits of this entry.
58    fn bits(self) -> usize;
59    /// Returns whether this entry is zero.
60    fn is_unused(&self) -> bool;
61    /// Returns whether this entry flag indicates present.
62    fn is_present(&self) -> bool;
63    /// For non-last level translation, returns whether this entry maps to a
64    /// huge frame.
65    fn is_huge(&self) -> bool;
66    /// Set this entry to zero.
67    fn clear(&mut self);
68}
page_table_entry/lib.rs

page_table_entry/
lib.rs
