diff --git a/Kernel/FileSystem/FileSystem.cpp b/Kernel/FileSystem/FileSystem.cpp
index 021da73153..817bf09c6b 100644
--- a/Kernel/FileSystem/FileSystem.cpp
+++ b/Kernel/FileSystem/FileSystem.cpp
@@ -107,7 +107,7 @@ void FS::lock_all()
     }
 }
 
-void FS::set_block_size(int block_size)
+void FS::set_block_size(size_t block_size)
 {
     ASSERT(block_size > 0);
     if (block_size == m_block_size)
diff --git a/Kernel/FileSystem/FileSystem.h b/Kernel/FileSystem/FileSystem.h
index 4eb70fd89e..72f809047f 100644
--- a/Kernel/FileSystem/FileSystem.h
+++ b/Kernel/FileSystem/FileSystem.h
@@ -85,20 +85,20 @@ public:
 
     virtual void flush_writes() {}
 
-    int block_size() const { return m_block_size; }
+    size_t block_size() const { return m_block_size; }
 
     virtual bool is_file_backed() const { return false; }
 
 protected:
     FS();
 
-    void set_block_size(int);
+    void set_block_size(size_t);
 
     mutable Lock m_lock { "FS" };
 
 private:
     unsigned m_fsid { 0 };
-    int m_block_size { 0 };
+    size_t m_block_size { 0 };
     bool m_readonly { false };
 };
 
diff --git a/Kernel/FileSystem/ProcFS.cpp b/Kernel/FileSystem/ProcFS.cpp
index 0b15d7337a..e157ed7277 100644
--- a/Kernel/FileSystem/ProcFS.cpp
+++ b/Kernel/FileSystem/ProcFS.cpp
@@ -742,7 +742,7 @@ Optional<KBuffer> procfs$df(InodeIdentifier)
         fs_object.add("total_inode_count", fs.total_inode_count());
         fs_object.add("free_inode_count", fs.free_inode_count());
         fs_object.add("mount_point", mount.absolute_path());
-        fs_object.add("block_size", fs.block_size());
+        fs_object.add("block_size", static_cast<u64>(fs.block_size()));
         fs_object.add("readonly", fs.is_readonly());
         fs_object.add("mount_flags", mount.flags());