diff --git a/inc/winfsp/fsctl.h b/inc/winfsp/fsctl.h
index ab80ef3d..9510f2a7 100644
--- a/inc/winfsp/fsctl.h
+++ b/inc/winfsp/fsctl.h
@@ -153,6 +153,8 @@ typedef struct
             {
                 UINT64 UserContext;     /* open file user context (unique file id) */
                 UINT64 UserContext2;    /* kernel file object user context (only low 32 bits valid) */
+                UINT64 AllocationSize;  /* file allocation size */
+                UINT64 FileSize;        /* file size */
                 UINT32 GrantedAccess;   /* FILE_{READ_DATA,WRITE_DATA,etc.} */
             } Opened;
             /* IoStatus.Status == STATUS_REPARSE */
diff --git a/inc/winfsp/winfsp.h b/inc/winfsp/winfsp.h
index ec345378..908434e5 100644
--- a/inc/winfsp/winfsp.h
+++ b/inc/winfsp/winfsp.h
@@ -28,7 +28,13 @@ typedef struct _FSP_FILE_SYSTEM FSP_FILE_SYSTEM;
 typedef struct _FSP_FILE_NODE
 {
     PVOID UserContext;
-    DWORD Flags;
+    UINT64 AllocationSize;
+    UINT64 FileSize;
+    struct
+    {
+        BOOLEAN DeleteOnClose:1;
+        BOOLEAN DeletePending:1;
+    } Flags;
     struct
     {
         ULONG OpenCount;
diff --git a/src/dll/create.c b/src/dll/create.c
index b75a7588..781fdb19 100644
--- a/src/dll/create.c
+++ b/src/dll/create.c
@@ -51,7 +51,7 @@ static NTSTATUS FspFileSystemOpCreate_FileCreate(FSP_FILE_SYSTEM *FileSystem,
     if (!NT_SUCCESS(Result))
         return FspFileSystemSendResponseWithStatus(FileSystem, Request, Result);
 
-    FileNode->Flags = 0;
+    memset(&FileNode->Flags, 0, sizeof FileNode->Flags);
     memset(&FileNode->ShareAccess, 0, sizeof FileNode->ShareAccess);
 
     FspShareCheck(FileSystem, GrantedAccess, Request->Req.Create.ShareAccess, FileNode);
@@ -129,7 +129,7 @@ static NTSTATUS FspFileSystemOpCreate_FileOpenIf(FSP_FILE_SYSTEM *FileSystem,
         if (!NT_SUCCESS(Result))
             return FspFileSystemSendResponseWithStatus(FileSystem, Request, Result);
 
-        FileNode->Flags = 0;
+        memset(&FileNode->Flags, 0, sizeof FileNode->Flags);
         memset(&FileNode->ShareAccess, 0, sizeof FileNode->ShareAccess);
     }
 
@@ -229,7 +229,7 @@ static NTSTATUS FspFileSystemOpCreate_FileOverwriteIf(FSP_FILE_SYSTEM *FileSyste
         if (!NT_SUCCESS(Result))
             return FspFileSystemSendResponseWithStatus(FileSystem, Request, Result);
 
-        FileNode->Flags = 0;
+        memset(&FileNode->Flags, 0, sizeof FileNode->Flags);
         memset(&FileNode->ShareAccess, 0, sizeof FileNode->ShareAccess);
     }
 
@@ -322,6 +322,8 @@ FSP_API NTSTATUS FspFileSystemSendCreateResponse(FSP_FILE_SYSTEM *FileSystem,
     Response.IoStatus.Status = STATUS_SUCCESS;
     Response.IoStatus.Information = Information;
     Response.Rsp.Create.Opened.UserContext = (UINT_PTR)FileNode;
+    Response.Rsp.Create.Opened.AllocationSize = FileNode->AllocationSize;
+    Response.Rsp.Create.Opened.FileSize = FileNode->FileSize;
     Response.Rsp.Create.Opened.GrantedAccess = GrantedAccess;
     return FspFileSystemSendResponse(FileSystem, &Response);
 }
diff --git a/src/sys/create.c b/src/sys/create.c
index b3d23756..3ab327eb 100644
--- a/src/sys/create.c
+++ b/src/sys/create.c
@@ -382,6 +382,9 @@ VOID FspFsvolCreateComplete(
     /* get the FsContext from our Request and associate it with the Response UserContext */
     Request = FspIrpRequest(Irp);
     FsContext = FspIopRequestContext(Request, RequestFsContext);
+    FsContext->Header.AllocationSize.QuadPart = Response->Rsp.Create.Opened.AllocationSize;
+    FsContext->Header.FileSize.QuadPart = FsContext->Header.ValidDataLength.QuadPart =
+        Response->Rsp.Create.Opened.AllocationSize;
     FsContext->UserContext = Response->Rsp.Create.Opened.UserContext;
 
     /*