dll: create, cleanup

inc/winfsp/winfsp.h

@@ -22,14 +22,17 @@
 #include <winfsp/fsctl.h>
 
 /*
- * File System
+ * File Nodes
  */
-typedef struct _FSP_FILE_SYSTEM FSP_FILE_SYSTEM;
 typedef struct _FSP_FILE_NODE
 {
+    /* public */
     PVOID UserContext;
     UINT64 AllocationSize;
     UINT64 FileSize;
+    /* private */
+    CRITICAL_SECTION CriticalSection;
+    LONG OpenCount;
     struct
     {
         BOOLEAN DeleteOnClose:1;
@@ -46,6 +49,42 @@ typedef struct _FSP_FILE_NODE
         ULONG SharedDelete;
     } ShareAccess;
 } FSP_FILE_NODE;
+static inline
+VOID FspFileNodeInit(FSP_FILE_NODE *FileNode)
+{
+    memset(FileNode, 0, sizeof *FileNode);
+    InitializeCriticalSection(&FileNode->CriticalSection);
+}
+static inline
+VOID FspFileNodeFini(FSP_FILE_NODE *FileNode)
+{
+    DeleteCriticalSection(&FileNode->CriticalSection);
+}
+static inline
+VOID FspFileNodeLock(FSP_FILE_NODE *FileNode)
+{
+    EnterCriticalSection(&FileNode->CriticalSection);
+}
+static inline
+VOID FspFileNodeUnlock(FSP_FILE_NODE *FileNode)
+{
+    LeaveCriticalSection(&FileNode->CriticalSection);
+}
+static inline
+VOID FspFileNodeOpen(FSP_FILE_NODE *FileNode)
+{
+    InterlockedIncrement(&FileNode->OpenCount);
+}
+static inline
+LONG FspFileNodeClose(FSP_FILE_NODE *FileNode)
+{
+    return InterlockedDecrement(&FileNode->OpenCount);
+}
+
+/*
+ * File System
+ */
+typedef struct _FSP_FILE_SYSTEM FSP_FILE_SYSTEM;
 typedef VOID FSP_FILE_SYSTEM_DISPATCHER(FSP_FILE_SYSTEM *, FSP_FSCTL_TRANSACT_REQ *);
 typedef NTSTATUS FSP_FILE_SYSTEM_OPERATION(FSP_FILE_SYSTEM *, FSP_FSCTL_TRANSACT_REQ *);
 typedef struct _FSP_FILE_SYSTEM_INTERFACE
@@ -59,9 +98,9 @@ typedef struct _FSP_FILE_SYSTEM_INTERFACE
         FSP_FSCTL_TRANSACT_REQ *Request, FSP_FILE_NODE **PFileNode);
     NTSTATUS (*Overwrite)(FSP_FILE_SYSTEM *FileSystem,
         FSP_FSCTL_TRANSACT_REQ *Request, BOOLEAN ReplaceFileAttributes, FSP_FILE_NODE *FileNode);
-    NTSTATUS (*Cleanup)(FSP_FILE_SYSTEM *FileSystem,
+    VOID (*Cleanup)(FSP_FILE_SYSTEM *FileSystem,
-        FSP_FSCTL_TRANSACT_REQ *Request, FSP_FILE_NODE *FileNode);
+        FSP_FSCTL_TRANSACT_REQ *Request, FSP_FILE_NODE *FileNode, BOOLEAN Delete);
-    NTSTATUS (*Close)(FSP_FILE_SYSTEM *FileSystem,
+    VOID (*Close)(FSP_FILE_SYSTEM *FileSystem,
         FSP_FSCTL_TRANSACT_REQ *Request, FSP_FILE_NODE *FileNode);
 } FSP_FILE_SYSTEM_INTERFACE;
 typedef struct _FSP_FILE_SYSTEM

src/dll/cleanup.c

@@ -13,8 +13,22 @@ FSP_API NTSTATUS FspFileSystemOpCleanup(FSP_FILE_SYSTEM *FileSystem,
         return FspFileSystemSendResponseWithStatus(FileSystem, Request, STATUS_INVALID_DEVICE_REQUEST);
 
     FSP_FILE_NODE *FileNode = (PVOID)Request->Req.Close.UserContext;
+    BOOLEAN DeletePending;
+    LONG OpenCount;
 
-    FileSystem->Interface->Cleanup(FileSystem, Request, FileNode);
+    FspFileNodeLock(FileNode);
+
+    /* propagate the DeleteOnClose flag to DeletePending */
+    if (FileNode->Flags.DeleteOnClose)
+        FileNode->Flags.DeletePending = TRUE;
+    DeletePending = FileNode->Flags.DeletePending;
+
+    /* all handles on the kernel FILE_OBJECT gone; decrement the FileNode's OpenCount */
+    OpenCount = FspFileNodeClose(FileNode);
+
+    FspFileNodeUnlock(FileNode);
+
+    FileSystem->Interface->Cleanup(FileSystem, Request, FileNode, 0 == OpenCount && DeletePending);
 
     return FspFileSystemSendCleanupResponse(FileSystem, Request);
 }

src/dll/create.c

@@ -238,13 +238,16 @@ FSP_API NTSTATUS FspFileSystemPreCreateCheck(FSP_FILE_SYSTEM *FileSystem,
 FSP_API VOID FspFileSystemPostCreateCheck(FSP_FILE_SYSTEM *FileSystem,
     FSP_FSCTL_TRANSACT_REQ *Request, DWORD GrantedAccess, FSP_FILE_NODE *FileNode)
 {
-    memset(&FileNode->Flags, 0, sizeof FileNode->Flags);
+    FspFileNodeLock(FileNode);
-    memset(&FileNode->ShareAccess, 0, sizeof FileNode->ShareAccess);
 
     FspShareCheck(FileSystem, Request, GrantedAccess, FileNode);
 
     if (Request->Req.Create.CreateOptions & FILE_DELETE_ON_CLOSE)
         FileNode->Flags.DeleteOnClose = TRUE;
+
+    FspFileNodeOpen(FileNode);
+
+    FspFileNodeUnlock(FileNode);
 }
 
 FSP_API NTSTATUS FspFileSystemPreOpenCheck(FSP_FILE_SYSTEM *FileSystem,
@@ -259,15 +262,27 @@ FSP_API NTSTATUS FspFileSystemPostOpenCheck(FSP_FILE_SYSTEM *FileSystem,
 {
     NTSTATUS Result;
 
+    FspFileNodeLock(FileNode);
+
     if (FileNode->Flags.DeletePending)
-        return STATUS_DELETE_PENDING;
+    {
+        Result = STATUS_DELETE_PENDING;
+        goto exit;
+    }
 
     Result = FspShareCheck(FileSystem, Request, GrantedAccess, FileNode);
     if (!NT_SUCCESS(Result))
-        return Result;
+        goto exit;
 
     if (Request->Req.Create.CreateOptions & FILE_DELETE_ON_CLOSE)
         FileNode->Flags.DeleteOnClose = TRUE;
+
+    FspFileNodeOpen(FileNode);
+
+exit:
+    FspFileNodeUnlock(FileNode);
+
+    return Result;
 }
 
 FSP_API NTSTATUS FspFileSystemPreOverwriteCheck(FSP_FILE_SYSTEM *FileSystem,