Merge pull request #203 from arihant2math/statfs

Implement `sys_statfs` and `sys_fstatfs`

libkernel/src/fs/filesystems/ext4/mod.rs

@@ -362,6 +362,11 @@ where
         self.id
     }
 
+    fn magic(&self) -> u64 {
+        // TODO: retrieve magic from superblock instead of hardcoding
+        0xef53 // EXT4 magic number
+    }
+
     /// Returns the root inode of the mounted EXT4 filesystem.
     async fn root_inode(&self) -> Result<Arc<dyn Inode>> {
         let root = self.inner.read_root_inode().await?;

libkernel/src/fs/filesystems/fat32/mod.rs

@@ -168,6 +168,10 @@ impl Filesystem for Fat32Filesystem {
         self.id
     }
 
+    fn magic(&self) -> u64 {
+        0x4D44 // MSDOS magic number
+    }
+
     /// Get the root inode of this filesystem.
     async fn root_inode(&self) -> Result<Arc<dyn Inode>> {
         Ok(Arc::new(Fat32DirNode::new(

libkernel/src/fs/filesystems/tmpfs.rs

@@ -821,6 +821,10 @@ where
     fn id(&self) -> u64 {
         self.id
     }
+
+    fn magic(&self) -> u64 {
+        0x01021994 // Tmpfs magic number
+    }
 }
 
 #[cfg(test)]

libkernel/src/fs/mod.rs

@@ -65,6 +65,9 @@ pub trait Filesystem: Send + Sync {
     /// Returns the instance ID for this FS.
     fn id(&self) -> u64;
 
+    /// Get magic
+    fn magic(&self) -> u64;
+
     /// Flushes all pending data to the underlying storage device(s).
     ///
     /// The default implementation is a no-op so that read-only filesystems do