From 253de2170869191185724b8daaf612e6da7d6658 Mon Sep 17 00:00:00 2001
From: Bill Zissimopoulos <billziss@navimatics.com>
Date: Mon, 7 Dec 2015 13:19:17 -0800
Subject: [PATCH] sys: FspIrpContext*

---
 src/sys/create.c  |  5 ++---
 src/sys/driver.h  |  4 ++++
 src/sys/fsctl.c   |  2 +-
 src/sys/idevctl.c |  4 ++--
 src/sys/iop.c     | 16 ++++++++--------
 5 files changed, 17 insertions(+), 14 deletions(-)

diff --git a/src/sys/create.c b/src/sys/create.c
index ea37f2bb..d3550e75 100644
--- a/src/sys/create.c
+++ b/src/sys/create.c
@@ -346,7 +346,7 @@ NTSTATUS FspFsvolCreatePrepare(
     }
 
     /* send the user-mode handle to the user-mode file system */
-    Irp->Tail.Overlay.DriverContext[1] = UserModeAccessToken;
+    FspIrpContextHandle(Irp) = UserModeAccessToken;
     Request->Req.Create.AccessToken = (UINT_PTR)UserModeAccessToken;
 
     FSP_LEAVE_IOP();
@@ -388,8 +388,7 @@ VOID FspFsvolCreateComplete(
     ULONG Flags = IrpSp->Flags;
     KPROCESSOR_MODE RequestorMode =
         FlagOn(Flags, SL_FORCE_ACCESS_CHECK) ? UserMode : Irp->RequestorMode;
-    BOOLEAN HasTrailingBackslash =
-        0 != ((FSP_FSCTL_TRANSACT_REQ *)Irp->Tail.Overlay.DriverContext[0])->Req.Create.HasTrailingBackslash;
+    BOOLEAN HasTrailingBackslash = 0 != FspIrpContextRequest(Irp)->Req.Create.HasTrailingBackslash;
     FSP_FILE_CONTEXT *FsContext = FileObject->FsContext;
     ACCESS_MASK GrantedAccess;
     BOOLEAN Inserted = FALSE;
diff --git a/src/sys/driver.h b/src/sys/driver.h
index e7115af5..849df889 100644
--- a/src/sys/driver.h
+++ b/src/sys/driver.h
@@ -263,6 +263,10 @@ PIRP FspIoqEndProcessingIrp(FSP_IOQ *Ioq, UINT_PTR IrpHint);
 /* I/O processing */
 #define FSP_FSCTL_WORK                  \
     CTL_CODE(FILE_DEVICE_FILE_SYSTEM, 0x800 + 'W', METHOD_NEITHER, FILE_ANY_ACCESS)
+#define FspIrpContextRequest(Irp)       \
+    (*(FSP_FSCTL_TRANSACT_REQ **)&(Irp)->Tail.Overlay.DriverContext[0])
+#define FspIrpContextHandle(Irp)        \
+    (*(HANDLE *)&(Irp)->Tail.Overlay.DriverContext[1])
 NTSTATUS FspIopCreateRequest(
     PIRP Irp, PUNICODE_STRING FileName, ULONG ExtraSize, FSP_FSCTL_TRANSACT_REQ **PRequest);
 NTSTATUS FspIopPostWorkRequest(PDEVICE_OBJECT DeviceObject, FSP_FSCTL_TRANSACT_REQ *Request);
diff --git a/src/sys/fsctl.c b/src/sys/fsctl.c
index 6c429733..37217994 100644
--- a/src/sys/fsctl.c
+++ b/src/sys/fsctl.c
@@ -391,7 +391,7 @@ retry:
     ASSERT((PUINT8)Request + FSP_FSCTL_TRANSACT_REQ_SIZEMAX <= SystemBufferEnd);
     for (;;)
     {
-        PendingIrpRequest = PendingIrp->Tail.Overlay.DriverContext[0];
+        PendingIrpRequest = FspIrpContextRequest(PendingIrp);
 
         Result = FspIopDispatchPrepare(PendingIrp, PendingIrpRequest);
         if (!NT_SUCCESS(Result))
diff --git a/src/sys/idevctl.c b/src/sys/idevctl.c
index adede96a..1dcb6e45 100644
--- a/src/sys/idevctl.c
+++ b/src/sys/idevctl.c
@@ -42,7 +42,7 @@ static NTSTATUS FspFsvolInternalDeviceControl(
 
                 /* associate the passed Request with our Irp; acquire ownership of the Request */
                 Request->Hint = (UINT_PTR)Irp;
-                Irp->Tail.Overlay.DriverContext[0] = Request;
+                FspIrpContextRequest(Irp) = Request;
 
                 if (!FspIoqPostIrp(&FsvrtDeviceExtension->Ioq, Irp))
                 {
@@ -51,7 +51,7 @@ static NTSTATUS FspFsvolInternalDeviceControl(
 
                     /* disocciate the Request from our Irp; release ownership back to caller */
                     Request->Hint = 0;
-                    Irp->Tail.Overlay.DriverContext[0] = 0;
+                    FspIrpContextRequest(Irp) = 0;
 
                     Result = STATUS_CANCELLED;
                     goto exit;
diff --git a/src/sys/iop.c b/src/sys/iop.c
index a835d038..9b394413 100644
--- a/src/sys/iop.c
+++ b/src/sys/iop.c
@@ -58,7 +58,7 @@ NTSTATUS FspIopCreateRequest(
     }
 
     if (0 != Irp)
-        Irp->Tail.Overlay.DriverContext[0] = Request;
+        FspIrpContextRequest(Irp) = Request;
     *PRequest = Request;
 
     return STATUS_SUCCESS;
@@ -125,24 +125,24 @@ VOID FspIopCompleteIrpEx(PIRP Irp, NTSTATUS Result, BOOLEAN DeviceRelease)
     ASSERT(STATUS_PENDING != Result);
     ASSERT(0 == Irp->Tail.Overlay.DriverContext[3]);
 
-    if (0 != Irp->Tail.Overlay.DriverContext[0])
+    if (0 != FspIrpContextRequest(Irp))
     {
-        FspIopDeleteRequest(Irp->Tail.Overlay.DriverContext[0]);
-        Irp->Tail.Overlay.DriverContext[0] = 0;
+        FspIopDeleteRequest(FspIrpContextRequest(Irp));
+        FspIrpContextRequest(Irp) = 0;
     }
 
-    if (0 != Irp->Tail.Overlay.DriverContext[1])
+    if (0 != FspIrpContextHandle(Irp))
     {
 #if DBG
         NTSTATUS Result0;
-        Result0 = ObCloseHandle(Irp->Tail.Overlay.DriverContext[1], KernelMode);
+        Result0 = ObCloseHandle(FspIrpContextHandle(Irp), KernelMode);
         if (!NT_SUCCESS(Result0))
             DEBUGLOG("ObCloseHandle() = %s", NtStatusSym(Result0));
 #else
-        ObCloseHandle(Irp->Tail.Overlay.DriverContext[1], KernelMode);
+        ObCloseHandle(FspIrpContextHandle(Irp), KernelMode);
 #endif
 
-        Irp->Tail.Overlay.DriverContext[1] = 0;
+        FspIrpContextHandle(Irp) = 0;
     }
 
     PDEVICE_OBJECT DeviceObject = IoGetCurrentIrpStackLocation(Irp)->DeviceObject;