Merge branch 'master' into next

Signed-off-by: Joe Richey <[email protected]>

Author: josephlr

Changelog.md

@@ -6,7 +6,7 @@
   - `Port<T> = PortGeneric<T, ReadWriteAccess>`
   - `PortReadOnly<T> = PortGeneric<T, ReadOnlyAccess>`
   - `PortWriteOnly<T> = PortGeneric<T, WriteOnlyAccess>`
-- The following methods no longer require the `nightly` feature to be `const fn`s` ([#255](https://github.com/rust-osdev/x86_64/pull/255)):
+- The following methods no longer require the `nightly` feature to be `const fn`s ([#255](https://github.com/rust-osdev/x86_64/pull/255)):
   - `PageTable::new`
   - `GlobalDescriptorTable::from_raw_slice`
   - `MappedFrame::{start_address, size}`

src/addr.rs

@@ -531,21 +531,25 @@ impl Sub<PhysAddr> for PhysAddr {
 
 /// Align address downwards.
 ///
-/// Returns the greatest x with alignment `align` so that x <= addr. The alignment must be
-///  a power of 2.
+/// Returns the greatest `x` with alignment `align` so that `x <= addr`.
+///
+/// Panics if the alignment is not a power of two. Without the `const_fn`
+/// feature, the panic message will be "index out of bounds".
 #[inline]
-pub fn align_down(addr: u64, align: u64) -> u64 {
-    assert!(align.is_power_of_two(), "`align` must be a power of two");
+pub const fn align_down(addr: u64, align: u64) -> u64 {
+    const_assert!(align.is_power_of_two(), "`align` must be a power of two");
     addr & !(align - 1)
 }
 
 /// Align address upwards.
 ///
-/// Returns the smallest x with alignment `align` so that x >= addr. The alignment must be
-/// a power of 2.
+/// Returns the smallest `x` with alignment `align` so that `x >= addr`.
+///
+/// Panics if the alignment is not a power of two. Without the `const_fn`
+/// feature, the panic message will be "index out of bounds".
 #[inline]
-pub fn align_up(addr: u64, align: u64) -> u64 {
-    assert!(align.is_power_of_two(), "`align` must be a power of two");
+pub const fn align_up(addr: u64, align: u64) -> u64 {
+    const_assert!(align.is_power_of_two(), "`align` must be a power of two");
     let align_mask = align - 1;
     if addr & align_mask == 0 {
         addr // already aligned

src/asm/asm.s

@@ -123,6 +123,12 @@ _x86_64_asm_lidt:
     lidt (%rdi)
     retq
 
+.global _x86_64_asm_sgdt
+.p2align 4
+_x86_64_asm_sgdt:
+    sgdt (%rdi)
+    retq
+
 .global _x86_64_asm_sidt
 .p2align 4
 _x86_64_asm_sidt:
@@ -173,6 +179,36 @@ _x86_64_asm_load_gs:
     mov %di, %gs
     retq
 
+.global _x86_64_asm_get_ss
+.p2align 4
+_x86_64_asm_get_ss:
+    mov %ss, %ax
+    retq
+
+.global _x86_64_asm_get_ds
+.p2align 4
+_x86_64_asm_get_ds:
+    mov %ds, %ax
+    retq
+
+.global _x86_64_asm_get_es
+.p2align 4
+_x86_64_asm_get_es:
+    mov %es, %ax
+    retq
+
+.global _x86_64_asm_get_fs
+.p2align 4
+_x86_64_asm_get_fs:
+    mov %fs, %ax
+    retq
+
+.global _x86_64_asm_get_gs
+.p2align 4
+_x86_64_asm_get_gs:
+    mov %gs, %ax
+    retq
+
 .global _x86_64_asm_swapgs
 .p2align 4
 _x86_64_asm_swapgs:

src/asm/mod.rs

@@ -1,5 +1,5 @@
 #[link(name = "x86_64_asm", kind = "static")]
-extern "C" {
+extern "sysv64" {
     #[cfg_attr(
         any(target_env = "gnu", target_env = "musl"),
         link_name = "_x86_64_asm_interrupt_enable"
@@ -114,6 +114,36 @@ extern "C" {
     )]
     pub(crate) fn x86_64_asm_load_gs(sel: u16);
 
+    #[cfg_attr(
+        any(target_env = "gnu", target_env = "musl"),
+        link_name = "_x86_64_asm_get_ss"
+    )]
+    pub(crate) fn x86_64_asm_get_ss() -> u16;
+
+    #[cfg_attr(
+        any(target_env = "gnu", target_env = "musl"),
+        link_name = "_x86_64_asm_get_ds"
+    )]
+    pub(crate) fn x86_64_asm_get_ds() -> u16;
+
+    #[cfg_attr(
+        any(target_env = "gnu", target_env = "musl"),
+        link_name = "_x86_64_asm_get_es"
+    )]
+    pub(crate) fn x86_64_asm_get_es() -> u16;
+
+    #[cfg_attr(
+        any(target_env = "gnu", target_env = "musl"),
+        link_name = "_x86_64_asm_get_fs"
+    )]
+    pub(crate) fn x86_64_asm_get_fs() -> u16;
+
+    #[cfg_attr(
+        any(target_env = "gnu", target_env = "musl"),
+        link_name = "_x86_64_asm_get_gs"
+    )]
+    pub(crate) fn x86_64_asm_get_gs() -> u16;
+
     #[cfg_attr(
         any(target_env = "gnu", target_env = "musl"),
         link_name = "_x86_64_asm_swapgs"
@@ -138,6 +168,12 @@ extern "C" {
     )]
     pub(crate) fn x86_64_asm_lidt(idt: *const crate::instructions::tables::DescriptorTablePointer);
 
+    #[cfg_attr(
+        any(target_env = "gnu", target_env = "musl"),
+        link_name = "_x86_64_asm_sgdt"
+    )]
+    pub(crate) fn x86_64_asm_sgdt(gdt: *mut crate::instructions::tables::DescriptorTablePointer);
+
     #[cfg_attr(
         any(target_env = "gnu", target_env = "musl"),
         link_name = "_x86_64_asm_sidt"