fix: solve issues caused by removing const traits

According to rust-lang/rust#110395, const
traits cannot be used anymore.

Author: Celve

allocator/src/buddy_allocator.rs

@@ -64,7 +64,11 @@ impl BuddyAllocatorInner {
             user: 0,
             allocated: 0,
             total: 0,
-            gran: max(gran, size_of::<usize>()),
+            gran: if gran > size_of::<usize>() {
+                gran
+            } else {
+                size_of::<usize>()
+            },
         }
     }
 

allocator/src/lib.rs

@@ -1,5 +1,4 @@
 #![no_std]
-#![feature(const_cmp)]
 
 pub mod buddy_allocator;
 pub mod linked_list;

kernel/src/main.rs

@@ -11,8 +11,6 @@
     const_trait_impl,
     const_for,
     const_mut_refs,
-    const_convert,
-    const_default_impls,
     sync_unsafe_cell
 )]
 

kernel/src/mem/normal/allocator.rs

@@ -14,7 +14,7 @@ pub struct FrameAllocatorInner {
     recycled: Vec<PhyPageNum>,
 }
 
-impl const Default for FrameAllocatorInner {
+impl Default for FrameAllocatorInner {
     fn default() -> Self {
         Self {
             start: PhyPageNum(0),
@@ -24,7 +24,7 @@ impl const Default for FrameAllocatorInner {
     }
 }
 
-impl const Default for FrameAllocator {
+impl Default for FrameAllocator {
     fn default() -> Self {
         Self {
             inner: Spin::new(FrameAllocatorInner::default()),

kernel/src/mem/normal/mod.rs

@@ -1,11 +1,14 @@
-use crate::{config::MEMORY_END, mem::allocator::PageAllocator};
+use lazy_static::lazy_static;
 
 use self::allocator::FrameAllocator;
+use crate::{config::MEMORY_END, mem::allocator::PageAllocator};
 
 pub mod allocator;
 pub mod page;
 
-pub static FRAME_ALLOCATOR: FrameAllocator = FrameAllocator::default();
+lazy_static! {
+    pub static ref FRAME_ALLOCATOR: FrameAllocator = FrameAllocator::default();
+}
 
 pub fn init_frame_allocator() {
     extern "C" {

kernel/src/mem/slab/allocator.rs

@@ -88,7 +88,11 @@ impl BuddyAllocatorInner {
             user: 0,
             allocated: 0,
             total: 0,
-            gran: max(gran, size_of::<usize>()),
+            gran: if gran > size_of::<usize>() {
+                gran
+            } else {
+                size_of::<usize>()
+            },
         }
     }
 

kernel/src/mem/table.rs

@@ -36,7 +36,7 @@ impl MemTable {
     }
 }
 
-impl const Default for MemTable {
+impl Default for MemTable {
     fn default() -> Self {
         Self {
             units: Default::default(),
@@ -59,7 +59,7 @@ impl MemUnit {
     }
 }
 
-impl const Default for MemUnit {
+impl Default for MemUnit {
     fn default() -> Self {
         Self {
             start_ppn: PhyPageNum(0),

kernel/src/mm/address.rs

@@ -71,7 +71,7 @@ impl From<usize> for VirAddr {
     }
 }
 
-impl const From<usize> for PhyPageNum {
+impl From<usize> for PhyPageNum {
     fn from(value: usize) -> Self {
         Self(truncate_page_num!(truncate_phy_addr!(value)) >> PAGE_SIZE_BITS)
     }
@@ -91,7 +91,7 @@ impl From<usize> for GenOffset {
 
 // from any to usize
 
-impl const From<PhyAddr> for usize {
+impl From<PhyAddr> for usize {
     fn from(value: PhyAddr) -> Self {
         value.0
     }
@@ -372,7 +372,7 @@ impl ops::Sub<usize> for PhyPageNum {
     }
 }
 
-impl const ops::Sub<PhyPageNum> for PhyPageNum {
+impl ops::Sub<PhyPageNum> for PhyPageNum {
     type Output = usize;
 
     fn sub(self, rhs: PhyPageNum) -> Self::Output {