From e555d8c616d218a4be3e442d8c26ce77a767f8c8 Mon Sep 17 00:00:00 2001
From: Chen Chengjun <chenchengjun.ccj@antgroup.com>
Date: Fri, 23 Aug 2024 19:28:44 +0800
Subject: [PATCH] Set the access bit when mapping a frame to the page table in
 userspace

---
 ostd/src/mm/vm_space.rs | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/ostd/src/mm/vm_space.rs b/ostd/src/mm/vm_space.rs
index a84111347..2c3b76a1a 100644
--- a/ostd/src/mm/vm_space.rs
+++ b/ostd/src/mm/vm_space.rs
@@ -306,10 +306,12 @@ impl CursorMut<'_> {
     /// Map a frame into the current slot.
     ///
     /// This method will bring the cursor to the next slot after the modification.
-    pub fn map(&mut self, frame: Frame, prop: PageProperty) {
+    pub fn map(&mut self, frame: Frame, mut prop: PageProperty) {
         let start_va = self.virt_addr();
         let end_va = start_va + frame.size();
-
+        // TODO: this is a temporary fix to avoid the overhead of setting ACCESSED bit in userspace.
+        // When this bit is truly enabled, it needs to be set at a more appropriate location.
+        prop.flags |= PageFlags::ACCESSED;
         // SAFETY: It is safe to map untyped memory into the userspace.
         unsafe {
             self.0.map(frame.into(), prop);