From bcff8a6d4ee5616a2e253da32ec069d4eeee197a Mon Sep 17 00:00:00 2001
From: Sameeh Jubran <sameeh@daynix.com>
Date: Wed, 28 Sep 2016 14:09:28 +0300
Subject: [PATCH] Fix source buffer mapping in PresentDisplayOnly

Part of source image mapped by PresentDisplayOnly
should be big enough to cover all rectangles being
transferred.

Signed-off-by: Sameeh Jubran <sameeh@daynix.com>
Signed-off-by: Dmitry Fleytman <dmitry@daynix.com>
Acked-by: Frediano Ziglio <fziglio@redhat.com>
---
 qxldod/QxlDod.cpp | 28 +++++++++++++++++++++++-----
 qxldod/QxlDod.h   |  2 ++
 2 files changed, 25 insertions(+), 5 deletions(-)

diff --git a/qxldod/QxlDod.cpp b/qxldod/QxlDod.cpp
index f5a2bc8..f70ed25 100755
--- a/qxldod/QxlDod.cpp
+++ b/qxldod/QxlDod.cpp
@@ -3666,12 +3666,11 @@ QxlDevice::ExecutePresentDisplayOnly(
     ctx->Mdl              = NULL;
     ctx->DisplaySource    = this;
 
-    // Alternate between synch and asynch execution, for demonstrating 
-    // that a real hardware implementation can do either
-
+    // Source bitmap is in user mode, must be locked under __try/__except
+    // and mapped to kernel space before use.
     {
-        // Map Source into kernel space, as Blt will be executed by system worker thread
-        UINT sizeToMap = ctx->SrcPitch * ctx->SrcHeight;
+        LONG maxHeight = GetMaxSourceMappingHeight(ctx->Moves, ctx->NumMoves, ctx->DirtyRect, ctx->NumDirtyRects);
+        UINT sizeToMap = ctx->SrcPitch * maxHeight;
 
         PMDL mdl = IoAllocateMdl((PVOID)SrcAddr, sizeToMap,  FALSE, FALSE, NULL);
         if(!mdl)
@@ -4523,6 +4522,25 @@ void QxlDevice::SetMonitorConfig(QXLHead * monitor_config)
     AsyncIo(QXL_IO_MONITORS_CONFIG_ASYNC, 0);
 }
 
+LONG QxlDevice::GetMaxSourceMappingHeight(D3DKMT_MOVE_RECT* Moves, ULONG NumMoves, RECT* DirtyRects, ULONG NumDirtyRects)
+{
+    LONG maxHeight = 0;
+    if (Moves != NULL) {
+        for (UINT i = 0; i < NumMoves; i++) {
+            const POINT&   pSourcePoint = Moves[i].SourcePoint;
+            const RECT&    pDestRect = Moves[i].DestRect;
+            maxHeight = MAX(maxHeight, pDestRect.bottom - pDestRect.top + pSourcePoint.y);
+        }
+    }
+    if (DirtyRects != NULL) {
+        for (UINT i = 0; i < NumDirtyRects; i++) {
+            const RECT&    pDirtyRect = DirtyRects[i];
+            maxHeight = MAX(maxHeight, pDirtyRect.bottom);
+        }
+    }
+    return maxHeight;
+}
+
 NTSTATUS QxlDevice::Escape(_In_ CONST DXGKARG_ESCAPE* pEscape)
 {
     size_t          data_size(sizeof(uint32_t));
diff --git a/qxldod/QxlDod.h b/qxldod/QxlDod.h
index c808eb1..bf16724 100755
--- a/qxldod/QxlDod.h
+++ b/qxldod/QxlDod.h
@@ -542,6 +542,8 @@ private:
     NTSTATUS SetCustomDisplay(QXLEscapeSetCustomDisplay* custom_display);
     void SetMonitorConfig(QXLHead* monitor_config);
 
+    static LONG GetMaxSourceMappingHeight(D3DKMT_MOVE_RECT* Moves, ULONG NumMoves, RECT* DirtyRects, ULONG NumDirtyRects);
+
 private:
     PUCHAR m_IoBase;
     BOOLEAN m_IoMapped;