From e06509e3809b29b31eeb2e0ba0728c64e3ad3b04 Mon Sep 17 00:00:00 2001
From: Ruihan Li <lrh2000@pku.edu.cn>
Date: Fri, 18 Apr 2025 12:03:58 +0800
Subject: [PATCH] Make some `unsafe` blocks shorter

---
 ostd/src/arch/riscv/mod.rs |  8 +++-----
 ostd/src/arch/x86/mod.rs   | 12 ++++--------
 ostd/src/boot/smp.rs       | 22 +++++++---------------
 ostd/src/lib.rs            |  5 ++---
 4 files changed, 16 insertions(+), 31 deletions(-)

diff --git a/ostd/src/arch/riscv/mod.rs b/ostd/src/arch/riscv/mod.rs
index a6477a78..4360b2a9 100644
--- a/ostd/src/arch/riscv/mod.rs
+++ b/ostd/src/arch/riscv/mod.rs
@@ -23,13 +23,11 @@ pub(crate) fn init_cvm_guest() {
 }
 
 pub(crate) unsafe fn late_init_on_bsp() {
-    // SAFETY: this function is only called once on BSP.
-    unsafe {
-        trap::init(true);
-    }
+    // SAFETY: This function is only called once on BSP.
+    unsafe { trap::init(true) };
     irq::init();
 
-    // SAFETY: we're on the BSP and we're ready to boot all APs.
+    // SAFETY: We're on the BSP and we're ready to boot all APs.
     unsafe { crate::boot::smp::boot_all_aps() };
 
     timer::init();
diff --git a/ostd/src/arch/x86/mod.rs b/ostd/src/arch/x86/mod.rs
index 88412e05..44aeb73e 100644
--- a/ostd/src/arch/x86/mod.rs
+++ b/ostd/src/arch/x86/mod.rs
@@ -64,10 +64,8 @@ static CPU_FEATURES: Once<FeatureInfo> = Once::new();
 ///
 /// This function must be called only once on the bootstrapping processor.
 pub(crate) unsafe fn late_init_on_bsp() {
-    // SAFETY: this function is only called once on BSP.
-    unsafe {
-        trap::init(true);
-    }
+    // SAFETY: This function is only called once on BSP.
+    unsafe { trap::init(true) };
     irq::init();
 
     kernel::acpi::init();
@@ -87,7 +85,7 @@ pub(crate) unsafe fn late_init_on_bsp() {
     kernel::tsc::init_tsc_freq();
     timer::init_bsp();
 
-    // SAFETY: we're on the BSP and we're ready to boot all APs.
+    // SAFETY: We're on the BSP and we're ready to boot all APs.
     unsafe { crate::boot::smp::boot_all_aps() };
 
     if_tdx_enabled!({
@@ -105,9 +103,7 @@ pub(crate) unsafe fn late_init_on_bsp() {
     // 1. All the system device memory have been removed from the builder.
     // 2. All the port I/O regions belonging to the system device are defined using the macros.
     // 3. `MAX_IO_PORT` defined in `crate::arch::io` is the maximum value specified by x86-64.
-    unsafe {
-        crate::io::init(io_mem_builder);
-    }
+    unsafe { crate::io::init(io_mem_builder) };
 }
 
 /// Architecture-specific initialization on the application processor.
diff --git a/ostd/src/boot/smp.rs b/ostd/src/boot/smp.rs
index 22b3d10f..6fec15eb 100644
--- a/ostd/src/boot/smp.rs
+++ b/ostd/src/boot/smp.rs
@@ -142,29 +142,21 @@ pub fn register_ap_entry(entry: fn()) {
 #[no_mangle]
 fn ap_early_entry(cpu_id: u32) -> ! {
     // SAFETY: `cpu_id` is the correct value of the CPU ID.
-    unsafe {
-        cpu::init_on_ap(cpu_id);
-    }
+    unsafe { cpu::init_on_ap(cpu_id) };
 
     crate::arch::enable_cpu_features();
 
-    // SAFETY: this function is only called once on this AP.
-    unsafe {
-        crate::arch::trap::init(false);
-    }
+    // SAFETY: This function is only called once on this AP.
+    unsafe { crate::arch::trap::init(false) };
 
-    // SAFETY: this function is only called once on this AP, after the BSP has
+    // SAFETY: This function is only called once on this AP, after the BSP has
     // done the architecture-specific initialization.
-    unsafe {
-        crate::arch::init_on_ap();
-    }
+    unsafe { crate::arch::init_on_ap() };
 
     crate::arch::irq::enable_local();
 
-    // SAFETY: this function is only called once on this AP.
-    unsafe {
-        crate::mm::kspace::activate_kernel_page_table();
-    }
+    // SAFETY: This function is only called once on this AP.
+    unsafe { crate::mm::kspace::activate_kernel_page_table() };
 
     // Mark the AP as started.
     let ap_boot_info = AP_BOOT_INFO.get().unwrap();
diff --git a/ostd/src/lib.rs b/ostd/src/lib.rs
index fd081397..65df0c7d 100644
--- a/ostd/src/lib.rs
+++ b/ostd/src/lib.rs
@@ -78,9 +78,8 @@ unsafe fn init() {
 
     // SAFETY: This function is called only once, before `allocator::init`
     // and after memory regions are initialized.
-    unsafe {
-        mm::frame::allocator::init_early_allocator();
-    }
+    unsafe { mm::frame::allocator::init_early_allocator() };
+
     #[cfg(target_arch = "x86_64")]
     arch::if_tdx_enabled!({
     } else {