Impl syscalls and change some interfaces for pass os comp’s final online tests

Cargo.toml

@@ -30,7 +30,7 @@ itertools = { version = "0.13.0", default-features = false }
 acpi = "5.2.0"
 align_ext = "0.1.0"
 xmas-elf = "0.10.0"
-ext4_rs = "1.3.2"
+another_ext4 = { git = "https://github.com/SMS-Derfflinger/another_ext4", branch = "main" }
 
 [target.'cfg(any(target_arch = "riscv64", target_arch = "loongarch64"))'.dependencies]
 virtio-drivers = { version = "0.11.0" }

src/driver/virtio/virtio_blk.rs

@@ -84,7 +84,23 @@ where
 
     fn submit(&self, req: BlockDeviceRequest) -> KResult<()> {
         match req {
-            BlockDeviceRequest::Write { .. } => todo!(),
+            BlockDeviceRequest::Write {
+                sector,
+                count,
+                buffer,
+            } => {
+                let mut dev = self.lock();
+                for ((start, len), buffer_page) in
+                    Chunks::new(sector as usize, count as usize, 8).zip(buffer.iter())
+                {
+                    let buffer = unsafe {
+                        // SAFETY: Pages in `req.buffer` are guaranteed to be exclusively owned by us.
+                        &buffer_page.as_memblk().as_bytes()[..len as usize * 512]
+                    };
+
+                    dev.write_blocks(start, buffer).map_err(|_| EIO)?;
+                }
+            }
             BlockDeviceRequest::Read {
                 sector,
                 count,