Add a VMO pointer to VNode.

This way, if anyone tries to map an already mapped file, we share the VMO.

2 files changed, 7 insertions, 0 deletions

diff --git a/VirtualFileSystem/VirtualFileSystem.cpp b/VirtualFileSystem/VirtualFileSystem.cpp
index da482bd9fa..31cdf58d2e 100644
--- a/VirtualFileSystem/VirtualFileSystem.cpp
+++ b/VirtualFileSystem/VirtualFileSystem.cpp
@@ -180,6 +180,7 @@ auto VirtualFileSystem::allocateNode() -> RetainPtr<Node>
     ASSERT(node->retainCount == 0);
     node->retainCount = 1;
     node->m_vfs = this;
+    node->m_vmo = nullptr;
     return adopt(*node);
 }
 
@@ -197,6 +198,8 @@ void VirtualFileSystem::freeNode(Node* node)
         m_device2vnode.remove(encodedDevice(node->m_characterDevice->major(), node->m_characterDevice->minor()));
         node->m_characterDevice = nullptr;
     }
+    node->m_vfs = nullptr;
+    node->m_vmo = nullptr;
     m_nodeFreeList.append(move(node));
 }
 
diff --git a/VirtualFileSystem/VirtualFileSystem.h b/VirtualFileSystem/VirtualFileSystem.h
index 2f30223d72..a9afa9c33f 100644
--- a/VirtualFileSystem/VirtualFileSystem.h
+++ b/VirtualFileSystem/VirtualFileSystem.h
@@ -65,12 +65,16 @@ public:
         VirtualFileSystem* vfs() { return m_vfs; }
         const VirtualFileSystem* vfs() const { return m_vfs; }
 
+        void* vmo() { return m_vmo; }
+        void set_vmo(void* vmo) { m_vmo = vmo; }
+
     private:
         friend class VirtualFileSystem;
         VirtualFileSystem* m_vfs { nullptr };
         unsigned retainCount { 0 };
         CharacterDevice* m_characterDevice { nullptr };
         mutable InodeMetadata m_cachedMetadata;
+        void* m_vmo { nullptr };
     };
 
     static VirtualFileSystem& the() PURE;