From b35bf204db3a0ec926b846e4ef70833b29cbfa4b Mon Sep 17 00:00:00 2001
From: Bill Zissimopoulos <billziss@navimatics.com>
Date: Tue, 11 Jul 2017 14:17:17 -0700
Subject: [PATCH] sys: FspFileNodeTrySetFileInfoOnOpen

---
 src/sys/create.c |  2 +-
 src/sys/driver.h |  2 ++
 src/sys/file.c   | 39 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 42 insertions(+), 1 deletion(-)

diff --git a/src/sys/create.c b/src/sys/create.c
index 93fc1e9e..f1d89e0a 100644
--- a/src/sys/create.c
+++ b/src/sys/create.c
@@ -1098,7 +1098,7 @@ static NTSTATUS FspFsvolCreateTryOpen(PIRP Irp, const FSP_FSCTL_TRANSACT_RSP *Re
         return Result;
     }
 
-    FspFileNodeSetFileInfo(FileNode, FileObject, &Response->Rsp.Create.Opened.FileInfo,
+    FspFileNodeTrySetFileInfoOnOpen(FileNode, FileObject, &Response->Rsp.Create.Opened.FileInfo,
         FILE_CREATED == Response->IoStatus.Information);
 
     if (FlushImage)
diff --git a/src/sys/driver.h b/src/sys/driver.h
index 1ed4a19f..8b37875d 100644
--- a/src/sys/driver.h
+++ b/src/sys/driver.h
@@ -1350,6 +1350,8 @@ VOID FspFileNodeGetFileInfo(FSP_FILE_NODE *FileNode, FSP_FSCTL_FILE_INFO *FileIn
 BOOLEAN FspFileNodeTryGetFileInfo(FSP_FILE_NODE *FileNode, FSP_FSCTL_FILE_INFO *FileInfo);
 VOID FspFileNodeSetFileInfo(FSP_FILE_NODE *FileNode, PFILE_OBJECT CcFileObject,
     const FSP_FSCTL_FILE_INFO *FileInfo, BOOLEAN TruncateOnClose);
+BOOLEAN FspFileNodeTrySetFileInfoOnOpen(FSP_FILE_NODE *FileNode, PFILE_OBJECT CcFileObject,
+    const FSP_FSCTL_FILE_INFO *FileInfo, BOOLEAN TruncateOnClose);
 BOOLEAN FspFileNodeTrySetFileInfo(FSP_FILE_NODE *FileNode, PFILE_OBJECT CcFileObject,
     const FSP_FSCTL_FILE_INFO *FileInfo, ULONG InfoChangeNumber);
 VOID FspFileNodeInvalidateFileInfo(FSP_FILE_NODE *FileNode);
diff --git a/src/sys/file.c b/src/sys/file.c
index e9a1bef1..61983478 100644
--- a/src/sys/file.c
+++ b/src/sys/file.c
@@ -58,6 +58,8 @@ VOID FspFileNodeGetFileInfo(FSP_FILE_NODE *FileNode, FSP_FSCTL_FILE_INFO *FileIn
 BOOLEAN FspFileNodeTryGetFileInfo(FSP_FILE_NODE *FileNode, FSP_FSCTL_FILE_INFO *FileInfo);
 VOID FspFileNodeSetFileInfo(FSP_FILE_NODE *FileNode, PFILE_OBJECT CcFileObject,
     const FSP_FSCTL_FILE_INFO *FileInfo, BOOLEAN TruncateOnClose);
+BOOLEAN FspFileNodeTrySetFileInfoOnOpen(FSP_FILE_NODE *FileNode, PFILE_OBJECT CcFileObject,
+    const FSP_FSCTL_FILE_INFO *FileInfo, BOOLEAN TruncateOnClose);
 BOOLEAN FspFileNodeTrySetFileInfo(FSP_FILE_NODE *FileNode, PFILE_OBJECT CcFileObject,
     const FSP_FSCTL_FILE_INFO *FileInfo, ULONG InfoChangeNumber);
 VOID FspFileNodeInvalidateFileInfo(FSP_FILE_NODE *FileNode);
@@ -129,6 +131,7 @@ VOID FspFileNodeOplockComplete(PVOID Context, PIRP Irp);
 #pragma alloc_text(PAGE, FspFileNodeGetFileInfo)
 #pragma alloc_text(PAGE, FspFileNodeTryGetFileInfo)
 #pragma alloc_text(PAGE, FspFileNodeSetFileInfo)
+#pragma alloc_text(PAGE, FspFileNodeTrySetFileInfoOnOpen)
 #pragma alloc_text(PAGE, FspFileNodeTrySetFileInfo)
 #pragma alloc_text(PAGE, FspFileNodeInvalidateFileInfo)
 #pragma alloc_text(PAGE, FspFileNodeReferenceSecurity)
@@ -1660,6 +1663,42 @@ VOID FspFileNodeSetFileInfo(FSP_FILE_NODE *FileNode, PFILE_OBJECT CcFileObject,
     }
 }
 
+BOOLEAN FspFileNodeTrySetFileInfoOnOpen(FSP_FILE_NODE *FileNode, PFILE_OBJECT CcFileObject,
+    const FSP_FSCTL_FILE_INFO *FileInfo, BOOLEAN TruncateOnClose)
+{
+    PAGED_CODE();
+
+    BOOLEAN EarlyExit;
+
+    FspFsvolDeviceLockContextTable(FileNode->FsvolDeviceObject);
+    EarlyExit = 1 < FileNode->OpenCount;
+    FspFsvolDeviceUnlockContextTable(FileNode->FsvolDeviceObject);
+    if (EarlyExit)
+    {
+        FSP_FSVOL_DEVICE_EXTENSION *FsvolDeviceExtension =
+            FspFsvolDeviceExtension(FileNode->FsvolDeviceObject);
+        UINT64 AllocationSize = FileInfo->AllocationSize > FileInfo->FileSize ?
+            FileInfo->AllocationSize : FileInfo->FileSize;
+        UINT64 AllocationUnit;
+
+        AllocationUnit = FsvolDeviceExtension->VolumeParams.SectorSize *
+            FsvolDeviceExtension->VolumeParams.SectorsPerAllocationUnit;
+        AllocationSize = (AllocationSize + AllocationUnit - 1) / AllocationUnit * AllocationUnit;
+
+        if (TruncateOnClose)
+        {
+            if ((UINT64)FileNode->Header.AllocationSize.QuadPart != AllocationSize ||
+                (UINT64)FileNode->Header.FileSize.QuadPart != FileInfo->FileSize)
+                FileNode->TruncateOnClose = TRUE;
+        }
+
+        return FALSE;
+    }
+
+    FspFileNodeSetFileInfo(FileNode, CcFileObject, FileInfo, TruncateOnClose);
+    return TRUE;
+}
+
 BOOLEAN FspFileNodeTrySetFileInfo(FSP_FILE_NODE *FileNode, PFILE_OBJECT CcFileObject,
     const FSP_FSCTL_FILE_INFO *FileInfo, ULONG InfoChangeNumber)
 {