refactor: fix all warnings

kernel/arch/x86_64/src/mem/mod.rs

@@ -285,7 +285,7 @@ impl<'a, T: Sized> EarlyMapping<'a, T> {
         let layout = Layout::new::<T>();
         let aligned = physical.page_align_down::<L3>();
         let offset = physical.page_offset::<L3>();
-        let page_count = (offset + layout.size() + L3::SIZE - 1) / L3::SIZE;
+        let page_count = (offset + layout.size()).div_ceil(L3::SIZE);
 
         let virt = map_early_pages(aligned, page_count)?;
         let value = &mut *((virt + offset) as *mut T);
@@ -304,7 +304,7 @@ impl<'a, T: Sized> EarlyMapping<'a, T> {
         let layout = Layout::array::<T>(len).unwrap();
         let aligned = physical.page_align_down::<L3>();
         let offset = physical.page_offset::<L3>();
-        let page_count = (offset + layout.size() + L3::SIZE - 1) / L3::SIZE;
+        let page_count = (offset + layout.size()).div_ceil(L3::SIZE);
 
         let virt = map_early_pages(aligned, page_count)?;
         let value = core::slice::from_raw_parts_mut((virt + offset) as *mut T, len);
@@ -313,7 +313,7 @@ impl<'a, T: Sized> EarlyMapping<'a, T> {
     }
 }
 
-impl<'a, T: ?Sized> Deref for EarlyMapping<'a, T> {
+impl<T: ?Sized> Deref for EarlyMapping<'_, T> {
     type Target = T;
 
     fn deref(&self) -> &Self::Target {
@@ -321,13 +321,13 @@ impl<'a, T: ?Sized> Deref for EarlyMapping<'a, T> {
     }
 }
 
-impl<'a, T: ?Sized> DerefMut for EarlyMapping<'a, T> {
+impl<T: ?Sized> DerefMut for EarlyMapping<'_, T> {
     fn deref_mut(&mut self) -> &mut Self::Target {
         self.value
     }
 }
 
-impl<'a, T: ?Sized> Drop for EarlyMapping<'a, T> {
+impl<T: ?Sized> Drop for EarlyMapping<'_, T> {
     fn drop(&mut self) {
         let address = (self.value as *mut T).addr() & !(L3::SIZE - 1);