Git rid of mostly too complex x86 types.

Signed-off-by: Gerd Zellweger <mail@gerdzellweger.com>

6 files changed, 35 insertions, 119 deletions

diff --git a/src/bits64/paging.rs b/src/bits64/paging.rs
index ee30f79..5a8068e 100644
--- a/src/bits64/paging.rs
+++ b/src/bits64/paging.rs
@@ -1,53 +1,8 @@
 //! Description of the data-structures for IA-32e paging mode.
 
-use core::fmt;
-
-use ::paging::*;
-
 /// Represents a physical memory address
-#[derive(Copy, Clone, Debug, Eq, Ord, PartialEq, PartialOrd)]
-pub struct PAddr(u64);
-
-impl PAddr {
-    /// Convert to `u64`
-    pub const fn as_u64(&self) -> u64 {
-        self.0
-    }
-    /// Convert from `u64`
-    pub const fn from_u64(v: u64) -> Self {
-        PAddr(v)
-    }
-}
-
-impl fmt::Binary for PAddr {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        self.0.fmt(f)
-    }
-}
-
-impl fmt::Display for PAddr {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        self.0.fmt(f)
-    }
-}
-
-impl fmt::LowerHex for PAddr {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        self.0.fmt(f)
-    }
-}
-
-impl fmt::Octal for PAddr {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        self.0.fmt(f)
-    }
-}
-
-impl fmt::UpperHex for PAddr {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        self.0.fmt(f)
-    }
-}
+pub type PAddr = u64;
+pub type VAddr = usize;
 
 pub const BASE_PAGE_SIZE: u64 = 4096; // 4 KiB
 pub const LARGE_PAGE_SIZE: u64 = 1024 * 1024 * 2; // 2 MiB
@@ -75,26 +30,26 @@ pub type PT = [PTEntry; 512];
 
 /// Given virtual address calculate corresponding entry in PML4.
 #[inline]
-pub fn pml4_index(addr: VAddr) -> u64 {
-    (addr.as_u64() >> 39) & 0b111111111
+pub fn pml4_index(addr: VAddr) -> usize {
+    (addr >> 39) & 0b111111111
 }
 
 /// Given virtual address calculate corresponding entry in PDPT.
 #[inline]
-pub fn pdpt_index(addr: VAddr) -> u64 {
-    (addr.as_u64() >> 30) & 0b111111111
+pub fn pdpt_index(addr: VAddr) -> usize {
+    (addr >> 30) & 0b111111111
 }
 
 /// Given virtual address calculate corresponding entry in PD.
 #[inline]
-pub fn pd_index(addr: VAddr) -> u64 {
-    (addr.as_u64() >> 21) & 0b111111111
+pub fn pd_index(addr: VAddr) -> usize {
+    (addr >> 21) & 0b111111111
 }
 
 /// Given virtual address calculate corresponding entry in PT.
 #[inline]
-pub fn pt_index(addr: VAddr) -> u64 {
-    (addr.as_u64() >> 12) & 0b111111111
+pub fn pt_index(addr: VAddr) -> usize {
+    (addr >> 12) & 0b111111111
 }
 
 /// PML4 Entry bits description.
@@ -131,14 +86,14 @@ impl PML4Entry {
     ///  * `pdpt` - The physical address of the pdpt table.
     ///  * `flags`- Additional flags for the entry.
     pub fn new(pdpt: PAddr, flags: PML4Entry) -> PML4Entry {
-        let pdpt_val = pdpt.as_u64();
+        let pdpt_val = pdpt;
         assert!(pdpt_val % BASE_PAGE_SIZE == 0);
         PML4Entry { bits: pdpt_val | flags.bits }
     }
 
     /// Retrieves the physical address in this entry.
     pub fn get_address(self) -> PAddr {
-        PAddr::from_u64(self.bits & ADDRESS_MASK)
+        self.bits & ADDRESS_MASK
     }
 
     check_flag!(doc = "Is page present?", is_present, PML4Entry::P);
@@ -197,14 +152,14 @@ impl PDPTEntry {
     ///  * `pd` - The physical address of the page directory.
     ///  * `flags`- Additional flags for the entry.
     pub fn new(pd: PAddr, flags: PDPTEntry) -> PDPTEntry {
-        let pd_val = pd.as_u64();
+        let pd_val = pd;
         assert!(pd_val % BASE_PAGE_SIZE == 0);
         PDPTEntry { bits: pd_val | flags.bits }
     }
 
     /// Retrieves the physical address in this entry.
     pub fn get_address(self) -> PAddr {
-        PAddr::from_u64(self.bits & ADDRESS_MASK)
+        self.bits & ADDRESS_MASK
     }
 
     check_flag!(doc = "Is page present?", is_present, PDPTEntry::P);
@@ -265,14 +220,14 @@ impl PDEntry {
     ///  * `pt` - The physical address of the page table.
     ///  * `flags`- Additional flags for the entry.
     pub fn new(pt: PAddr, flags: PDEntry) -> PDEntry {
-        let pt_val = pt.as_u64();
+        let pt_val = pt;
         assert!(pt_val % BASE_PAGE_SIZE == 0);
         PDEntry { bits: pt_val | flags.bits }
     }
 
     /// Retrieves the physical address in this entry.
     pub fn get_address(self) -> PAddr {
-        PAddr::from_u64(self.bits & ADDRESS_MASK)
+        self.bits & ADDRESS_MASK
     }
 
     check_flag!(doc = "Present; must be 1 to map a 2-MByte page or reference a page table.",
@@ -333,14 +288,14 @@ impl PTEntry {
     ///  * `page` - The physical address of the backing 4 KiB page.
     ///  * `flags`- Additional flags for the entry.
     pub fn new(page: PAddr, flags: PTEntry) -> PTEntry {
-        let page_val = page.as_u64();
+        let page_val = page;
         assert!(page_val % BASE_PAGE_SIZE == 0);
         PTEntry { bits: page_val | flags.bits }
     }
 
     /// Retrieves the physical address in this entry.
     pub fn get_address(self) -> PAddr {
-        PAddr::from_u64(self.bits & ADDRESS_MASK)
+        self.bits & ADDRESS_MASK
     }
 
     check_flag!(doc = "Present; must be 1 to map a 4-KByte page or reference a page table.",
diff --git a/src/bits64/segmentation.rs b/src/bits64/segmentation.rs
index 0c03780..bf39a82 100644
--- a/src/bits64/segmentation.rs
+++ b/src/bits64/segmentation.rs
@@ -16,6 +16,8 @@ pub struct Descriptor64 {
 
 impl Descriptor64 {
 
+    pub const NULL: Descriptor64 =  Descriptor64 { desc32: Descriptor::NULL, lower: 0, upper: 0 };
+
     pub(crate) fn apply_builder_settings(&mut self, builder: &DescriptorBuilder) {
         self.desc32.apply_builder_settings(builder);
         builder.base_limit.map(|(base, limit)| self.set_base_limit(base, limit));
diff --git a/src/dtables.rs b/src/dtables.rs
index 43eb13b..bdc3d9c 100644
--- a/src/dtables.rs
+++ b/src/dtables.rs
@@ -13,7 +13,19 @@ pub struct DescriptorTablePointer<Entry> {
 }
 
 impl<T> DescriptorTablePointer<T> {
-    pub fn new(slice: &[T]) -> Self {
+    pub fn new(tbl: &T) -> Self {
+        // GDT, LDT, and IDT all expect the limit to be set to "one less".
+        // See Intel 3a, Section 3.5.1 "Segment Descriptor Tables" and
+        // Section 6.10 "Interrupt Descriptor Table (IDT)".
+        let len = size_of::<T>() - 1;
+        assert!(len < 0x10000);
+        DescriptorTablePointer {
+            base: tbl as *const T,
+            limit: len as u16,
+        }
+    }
+
+    pub fn new_from_slice(slice: &[T]) -> Self {
         // GDT, LDT, and IDT all expect the limit to be set to "one less".
         // See Intel 3a, Section 3.5.1 "Segment Descriptor Tables" and
         // Section 6.10 "Interrupt Descriptor Table (IDT)".
diff --git a/src/lib.rs b/src/lib.rs
index 9458f2d..851fddb 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -36,7 +36,6 @@ pub mod dtables;
 pub mod io;
 pub mod irq;
 pub mod msr;
-pub mod paging;
 pub mod segmentation;
 pub mod task;
 pub mod tlb;
diff --git a/src/paging.rs b/src/paging.rs
deleted file mode 100644
index 06c86aa..0000000
--- a/src/paging.rs
+++ /dev/null
@@ -1,54 +0,0 @@
-//! Description of the data-structures for IA-32e paging mode.
-
-use core::fmt;
-
-/// Represent a virtual (linear) memory address
-#[derive(Copy, Clone, Debug, Eq, Ord, PartialEq, PartialOrd)]
-pub struct VAddr(usize);
-
-impl VAddr {
-    /// Convert to `usize`
-    pub const fn as_usize(&self) -> usize {
-        self.0
-    }
-
-    /// Convert from `usize`
-    pub const fn from_usize(v: usize) -> Self {
-        VAddr(v)
-    }
-
-    pub const fn as_u64(&self) -> u64 {
-        self.0 as u64
-    }
-
-}
-
-impl fmt::Binary for VAddr {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        self.0.fmt(f)
-    }
-}
-
-impl fmt::Display for VAddr {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        self.0.fmt(f)
-    }
-}
-
-impl fmt::LowerHex for VAddr {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        self.0.fmt(f)
-    }
-}
-
-impl fmt::Octal for VAddr {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        self.0.fmt(f)
-    }
-}
-
-impl fmt::UpperHex for VAddr {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        self.0.fmt(f)
-    }
-}
diff --git a/src/segmentation.rs b/src/segmentation.rs
index 6f17c75..f91a6ec 100644
--- a/src/segmentation.rs
+++ b/src/segmentation.rs
@@ -374,6 +374,8 @@ pub struct Descriptor {
 
 impl Descriptor {
 
+    pub const NULL: Descriptor = Descriptor { lower: 0, upper: 0 };
+
     pub(crate) fn apply_builder_settings(&mut self, builder: &DescriptorBuilder) {
         builder.dpl.map(|ring| self.set_dpl(ring));
         builder.base_limit.map(|(base, limit)| self.set_base_limit(base as u32, limit as u32));