Kernel: Expose the VMObject type of each Region in /proc/PID/vm

Kernel/FileSystem/ProcFS.cpp

@@ -315,6 +315,7 @@ Optional<KBuffer> procfs$pid_vm(InodeIdentifier identifier)
         region_object.add("amount_dirty", (u32)region.amount_dirty());
         region_object.add("cow_pages", region.cow_pages());
         region_object.add("name", region.name());
+        region_object.add("vmobject", region.vmobject().class_name());
 
         StringBuilder pagemap_builder;
         for (size_t i = 0; i < region.page_count(); ++i) {

Kernel/VM/AnonymousVMObject.h

@@ -44,6 +44,8 @@ protected:
     explicit AnonymousVMObject(size_t);
     explicit AnonymousVMObject(const AnonymousVMObject&);
 
+    virtual const char* class_name() const override { return "AnonymousVMObject"; }
+
 private:
     AnonymousVMObject(PhysicalAddress, size_t);
 

Kernel/VM/PrivateInodeVMObject.h

@@ -45,6 +45,8 @@ private:
     explicit PrivateInodeVMObject(Inode&, size_t);
     explicit PrivateInodeVMObject(const PrivateInodeVMObject&);
 
+    virtual const char* class_name() const override { return "PrivateInodeVMObject"; }
+
     PrivateInodeVMObject& operator=(const PrivateInodeVMObject&) = delete;
 };
 

Kernel/VM/PurgeableVMObject.h

@@ -50,6 +50,8 @@ private:
     explicit PurgeableVMObject(size_t);
     explicit PurgeableVMObject(const PurgeableVMObject&);
 
+    virtual const char* class_name() const override { return "PurgeableVMObject"; }
+
     int purge_impl();
 
     PurgeableVMObject& operator=(const PurgeableVMObject&) = delete;

Kernel/VM/SharedInodeVMObject.h

@@ -45,6 +45,8 @@ private:
     explicit SharedInodeVMObject(Inode&, size_t);
     explicit SharedInodeVMObject(const SharedInodeVMObject&);
 
+    virtual const char* class_name() const override { return "SharedInodeVMObject"; }
+
     SharedInodeVMObject& operator=(const SharedInodeVMObject&) = delete;
 };
 

Kernel/VM/VMObject.h

@@ -59,6 +59,8 @@ public:
 
     size_t size() const { return m_physical_pages.size() * PAGE_SIZE; }
 
+    virtual const char* class_name() const = 0;
+
     // For InlineLinkedListNode
     VMObject* m_next { nullptr };
     VMObject* m_prev { nullptr };