From 438dad888e1a08f2a14bbe7be26f660c14ecd958 Mon Sep 17 00:00:00 2001
From: Qingsong Chen <changxian.cqs@antgroup.com>
Date: Mon, 4 Nov 2024 03:39:54 +0000
Subject: [PATCH] Fix the range of IoMem's reader/writer

---
 ostd/src/io_mem.rs | 20 ++++++++------------
 1 file changed, 8 insertions(+), 12 deletions(-)

diff --git a/ostd/src/io_mem.rs b/ostd/src/io_mem.rs
index a4e844f3b..fd21d9b2c 100644
--- a/ostd/src/io_mem.rs
+++ b/ostd/src/io_mem.rs
@@ -125,8 +125,8 @@ impl IoMem {
         // safety of reading from the mapped physical address, and the mapping is valid.
         unsafe {
             VmReader::from_kernel_space(
-                self.kvirt_area.deref().start() as *mut u8,
-                self.kvirt_area.deref().len(),
+                (self.kvirt_area.deref().start() + self.offset) as *mut u8,
+                self.limit,
             )
         }
     }
@@ -136,8 +136,8 @@ impl IoMem {
         // safety of writing to the mapped physical address, and the mapping is valid.
         unsafe {
             VmWriter::from_kernel_space(
-                self.kvirt_area.deref().start() as *mut u8,
-                self.kvirt_area.deref().len(),
+                (self.kvirt_area.deref().start() + self.offset) as *mut u8,
+                self.limit,
             )
         }
     }
@@ -147,9 +147,7 @@ impl VmIo for IoMem {
     fn read(&self, offset: usize, writer: &mut VmWriter) -> Result<()> {
         let offset = offset + self.offset;
         if self
-            .kvirt_area
-            .deref()
-            .len()
+            .limit
             .checked_sub(offset)
             .is_none_or(|remain| remain < writer.avail())
         {
@@ -168,9 +166,7 @@ impl VmIo for IoMem {
     fn write(&self, offset: usize, reader: &mut VmReader) -> Result<()> {
         let offset = offset + self.offset;
         if self
-            .kvirt_area
-            .deref()
-            .len()
+            .limit
             .checked_sub(offset)
             .is_none_or(|remain| remain < reader.remain())
         {
@@ -189,10 +185,10 @@ impl VmIo for IoMem {
 
 impl VmIoOnce for IoMem {
     fn read_once<T: PodOnce>(&self, offset: usize) -> Result<T> {
-        self.reader().skip(offset + self.offset).read_once()
+        self.reader().skip(offset).read_once()
     }
 
     fn write_once<T: PodOnce>(&self, offset: usize, new_val: &T) -> Result<()> {
-        self.writer().skip(offset + self.offset).write_once(new_val)
+        self.writer().skip(offset).write_once(new_val)
     }
 }