From 3c92389185f0c9fa3b8c299a084b10c12bcab52c Mon Sep 17 00:00:00 2001
From: Zack Rusin <zack@kde.org>
Date: Sat, 9 Jul 2005 14:15:35 +0000
Subject: [PATCH] Patch from Thomas Winischhofer to kick out all pixmaps to
 system ram upon a     VT switch and vice versa when returning.

---
 exa/exa.c                      | 15 ++++++++++++---
 exa/exa_accel.c                | 15 ++++++++++++---
 exa/exa_migration.c            | 15 ++++++++++++---
 exa/exa_offscreen.c            | 20 ++++++++++++++++++++
 exa/exa_priv.h                 | 10 ++++++++++
 hw/xfree86/exa/exa.c           | 15 ++++++++++++---
 hw/xfree86/exa/exaPriv.h       | 10 ++++++++++
 hw/xfree86/exa/exa_accel.c     | 15 ++++++++++++---
 hw/xfree86/exa/exa_migration.c | 15 ++++++++++++---
 hw/xfree86/exa/exa_offscreen.c | 20 ++++++++++++++++++++
 hw/xfree86/exa/exa_priv.h      | 10 ++++++++++
 hw/xfree86/exa/exaoffscreen.c  | 20 ++++++++++++++++++++
 12 files changed, 162 insertions(+), 18 deletions(-)

diff --git a/exa/exa.c b/exa/exa.c
index 49c884595..50550b0a4 100644
--- a/exa/exa.c
+++ b/exa/exa.c
@@ -331,9 +331,9 @@ exaCreatePixmap(ScreenPtr pScreen, int w, int h, int depth)
     ExaPixmapPrivPtr	pExaPixmap;
     int			bpp;
     ScrnInfoPtr pScrn = XF86SCRNINFO(pScreen);
+    ExaScreenPriv(pScreen);
 
-    if (!pScrn->vtSema) {
-        ExaScreenPriv(pScreen);
+    if (!pScrn->vtSema || pExaScr->swappedOut) {
         pPixmap = pExaScr->SavedCreatePixmap(pScreen, w, h, depth);
     } else {
         bpp = BitsPerPixel (depth);
@@ -1127,6 +1127,7 @@ exaCloseScreen(int i, ScreenPtr pScreen)
 #ifdef RENDER
     PictureScreenPtr	ps = GetPictureScreenIfSet(pScreen);
 #endif
+    ScrnInfoPtr pScrn = XF86SCRNINFO(pScreen);
 
     pScreen->CreateGC = pExaScr->SavedCreateGC;
     pScreen->CloseScreen = pExaScr->SavedCloseScreen;
@@ -1142,6 +1143,8 @@ exaCloseScreen(int i, ScreenPtr pScreen)
 	ps->Composite = pExaScr->SavedComposite;
     }
 #endif
+    if (pExaScr->wrappedEnableDisableFB)
+	pScrn->EnableDisableFBAccess = pExaScr->SavedEnableDisableFBAccess;
 
     xfree (pExaScr);
 
@@ -1152,6 +1155,8 @@ Bool
 exaDriverInit (ScreenPtr		pScreen,
                ExaDriverPtr	pScreenInfo)
 {
+    /* Do NOT use XF86SCRNINFO macro here!! */
+    ScrnInfoPtr pScrn = xf86Screens[pScreen->myNum];
     ExaScreenPrivPtr pExaScr;
 
 #ifdef RENDER
@@ -1165,7 +1170,7 @@ exaDriverInit (ScreenPtr		pScreen,
 	exaGeneration = serverGeneration;
     }
 
-    pExaScr = xalloc (sizeof (ExaScreenPrivRec));
+    pExaScr = xcalloc (sizeof (ExaScreenPrivRec), 1);
 
     if (!pExaScr)
 	return FALSE;
@@ -1233,6 +1238,10 @@ exaDriverInit (ScreenPtr		pScreen,
     if (pExaScr->info->card.offScreenBase < pExaScr->info->card.memorySize) {
 	if (!exaOffscreenInit (pScreen))
             return FALSE;
+
+	pExaScr->SavedEnableDisableFBAccess = pScrn->EnableDisableFBAccess;
+	pScrn->EnableDisableFBAccess = exaEnableDisableFBAccess;
+	pExaScr->wrappedEnableDisableFB = TRUE;
     }
 
     return TRUE;
diff --git a/exa/exa_accel.c b/exa/exa_accel.c
index 49c884595..50550b0a4 100644
--- a/exa/exa_accel.c
+++ b/exa/exa_accel.c
@@ -331,9 +331,9 @@ exaCreatePixmap(ScreenPtr pScreen, int w, int h, int depth)
     ExaPixmapPrivPtr	pExaPixmap;
     int			bpp;
     ScrnInfoPtr pScrn = XF86SCRNINFO(pScreen);
+    ExaScreenPriv(pScreen);
 
-    if (!pScrn->vtSema) {
-        ExaScreenPriv(pScreen);
+    if (!pScrn->vtSema || pExaScr->swappedOut) {
         pPixmap = pExaScr->SavedCreatePixmap(pScreen, w, h, depth);
     } else {
         bpp = BitsPerPixel (depth);
@@ -1127,6 +1127,7 @@ exaCloseScreen(int i, ScreenPtr pScreen)
 #ifdef RENDER
     PictureScreenPtr	ps = GetPictureScreenIfSet(pScreen);
 #endif
+    ScrnInfoPtr pScrn = XF86SCRNINFO(pScreen);
 
     pScreen->CreateGC = pExaScr->SavedCreateGC;
     pScreen->CloseScreen = pExaScr->SavedCloseScreen;
@@ -1142,6 +1143,8 @@ exaCloseScreen(int i, ScreenPtr pScreen)
 	ps->Composite = pExaScr->SavedComposite;
     }
 #endif
+    if (pExaScr->wrappedEnableDisableFB)
+	pScrn->EnableDisableFBAccess = pExaScr->SavedEnableDisableFBAccess;
 
     xfree (pExaScr);
 
@@ -1152,6 +1155,8 @@ Bool
 exaDriverInit (ScreenPtr		pScreen,
                ExaDriverPtr	pScreenInfo)
 {
+    /* Do NOT use XF86SCRNINFO macro here!! */
+    ScrnInfoPtr pScrn = xf86Screens[pScreen->myNum];
     ExaScreenPrivPtr pExaScr;
 
 #ifdef RENDER
@@ -1165,7 +1170,7 @@ exaDriverInit (ScreenPtr		pScreen,
 	exaGeneration = serverGeneration;
     }
 
-    pExaScr = xalloc (sizeof (ExaScreenPrivRec));
+    pExaScr = xcalloc (sizeof (ExaScreenPrivRec), 1);
 
     if (!pExaScr)
 	return FALSE;
@@ -1233,6 +1238,10 @@ exaDriverInit (ScreenPtr		pScreen,
     if (pExaScr->info->card.offScreenBase < pExaScr->info->card.memorySize) {
 	if (!exaOffscreenInit (pScreen))
             return FALSE;
+
+	pExaScr->SavedEnableDisableFBAccess = pScrn->EnableDisableFBAccess;
+	pScrn->EnableDisableFBAccess = exaEnableDisableFBAccess;
+	pExaScr->wrappedEnableDisableFB = TRUE;
     }
 
     return TRUE;
diff --git a/exa/exa_migration.c b/exa/exa_migration.c
index 49c884595..50550b0a4 100644
--- a/exa/exa_migration.c
+++ b/exa/exa_migration.c
@@ -331,9 +331,9 @@ exaCreatePixmap(ScreenPtr pScreen, int w, int h, int depth)
     ExaPixmapPrivPtr	pExaPixmap;
     int			bpp;
     ScrnInfoPtr pScrn = XF86SCRNINFO(pScreen);
+    ExaScreenPriv(pScreen);
 
-    if (!pScrn->vtSema) {
-        ExaScreenPriv(pScreen);
+    if (!pScrn->vtSema || pExaScr->swappedOut) {
         pPixmap = pExaScr->SavedCreatePixmap(pScreen, w, h, depth);
     } else {
         bpp = BitsPerPixel (depth);
@@ -1127,6 +1127,7 @@ exaCloseScreen(int i, ScreenPtr pScreen)
 #ifdef RENDER
     PictureScreenPtr	ps = GetPictureScreenIfSet(pScreen);
 #endif
+    ScrnInfoPtr pScrn = XF86SCRNINFO(pScreen);
 
     pScreen->CreateGC = pExaScr->SavedCreateGC;
     pScreen->CloseScreen = pExaScr->SavedCloseScreen;
@@ -1142,6 +1143,8 @@ exaCloseScreen(int i, ScreenPtr pScreen)
 	ps->Composite = pExaScr->SavedComposite;
     }
 #endif
+    if (pExaScr->wrappedEnableDisableFB)
+	pScrn->EnableDisableFBAccess = pExaScr->SavedEnableDisableFBAccess;
 
     xfree (pExaScr);
 
@@ -1152,6 +1155,8 @@ Bool
 exaDriverInit (ScreenPtr		pScreen,
                ExaDriverPtr	pScreenInfo)
 {
+    /* Do NOT use XF86SCRNINFO macro here!! */
+    ScrnInfoPtr pScrn = xf86Screens[pScreen->myNum];
     ExaScreenPrivPtr pExaScr;
 
 #ifdef RENDER
@@ -1165,7 +1170,7 @@ exaDriverInit (ScreenPtr		pScreen,
 	exaGeneration = serverGeneration;
     }
 
-    pExaScr = xalloc (sizeof (ExaScreenPrivRec));
+    pExaScr = xcalloc (sizeof (ExaScreenPrivRec), 1);
 
     if (!pExaScr)
 	return FALSE;
@@ -1233,6 +1238,10 @@ exaDriverInit (ScreenPtr		pScreen,
     if (pExaScr->info->card.offScreenBase < pExaScr->info->card.memorySize) {
 	if (!exaOffscreenInit (pScreen))
             return FALSE;
+
+	pExaScr->SavedEnableDisableFBAccess = pScrn->EnableDisableFBAccess;
+	pScrn->EnableDisableFBAccess = exaEnableDisableFBAccess;
+	pExaScr->wrappedEnableDisableFB = TRUE;
     }
 
     return TRUE;
diff --git a/exa/exa_offscreen.c b/exa/exa_offscreen.c
index d62db9016..6b1a160ed 100644
--- a/exa/exa_offscreen.c
+++ b/exa/exa_offscreen.c
@@ -253,6 +253,26 @@ ExaOffscreenSwapIn (ScreenPtr pScreen)
     exaOffscreenInit (pScreen);
 }
 
+void
+exaEnableDisableFBAccess (int index, Bool enable)
+{
+    ScreenPtr pScreen = screenInfo.screens[index];
+    ExaScreenPriv (pScreen);
+
+    if (!enable) {
+	ExaOffscreenSwapOut (pScreen);
+	pExaScr->swappedOut = TRUE;
+    }
+
+    if (pExaScr->SavedEnableDisableFBAccess)
+       (*pExaScr->SavedEnableDisableFBAccess)(index, enable);
+
+    if (enable) {
+	ExaOffscreenSwapIn (pScreen);
+	pExaScr->swappedOut = FALSE;
+    }
+}
+
 /* merge the next free area into this one */
 static void
 ExaOffscreenMerge (ExaOffscreenArea *area)
diff --git a/exa/exa_priv.h b/exa/exa_priv.h
index 66d0b2faa..6372292e9 100644
--- a/exa/exa_priv.h
+++ b/exa/exa_priv.h
@@ -44,11 +44,15 @@
 #include "dix.h"
 #include "fb.h"
 #include "fboverlay.h"
+#ifdef RENDER
+#include "fbpict.h"
+#endif
 
 #ifndef EXA_MAX_FB
 #define EXA_MAX_FB   FB_OVERLAY_MAX
 #endif
 
+typedef void (*EnableDisableFBAccessProcPtr)(int, Bool);
 typedef struct {
     ExaDriverPtr info;
     CreateGCProcPtr 		 SavedCreateGC;
@@ -63,6 +67,9 @@ typedef struct {
 #ifdef RENDER
     CompositeProcPtr             SavedComposite;
 #endif
+    EnableDisableFBAccessProcPtr SavedEnableDisableFBAccess;
+    Bool			 wrappedEnableDisableFB;
+    Bool			 swappedOut;
 } ExaScreenPrivRec, *ExaScreenPrivPtr;
 
 /*
@@ -225,6 +232,9 @@ ExaOffscreenSwapIn (ScreenPtr pScreen);
 void
 ExaOffscreenFini (ScreenPtr pScreen);
 
+void
+exaEnableDisableFBAccess (int index, Bool enable);
+
 /* exa.c */
 void
 exaPixmapUseScreen (PixmapPtr pPixmap);
diff --git a/hw/xfree86/exa/exa.c b/hw/xfree86/exa/exa.c
index 49c884595..50550b0a4 100644
--- a/hw/xfree86/exa/exa.c
+++ b/hw/xfree86/exa/exa.c
@@ -331,9 +331,9 @@ exaCreatePixmap(ScreenPtr pScreen, int w, int h, int depth)
     ExaPixmapPrivPtr	pExaPixmap;
     int			bpp;
     ScrnInfoPtr pScrn = XF86SCRNINFO(pScreen);
+    ExaScreenPriv(pScreen);
 
-    if (!pScrn->vtSema) {
-        ExaScreenPriv(pScreen);
+    if (!pScrn->vtSema || pExaScr->swappedOut) {
         pPixmap = pExaScr->SavedCreatePixmap(pScreen, w, h, depth);
     } else {
         bpp = BitsPerPixel (depth);
@@ -1127,6 +1127,7 @@ exaCloseScreen(int i, ScreenPtr pScreen)
 #ifdef RENDER
     PictureScreenPtr	ps = GetPictureScreenIfSet(pScreen);
 #endif
+    ScrnInfoPtr pScrn = XF86SCRNINFO(pScreen);
 
     pScreen->CreateGC = pExaScr->SavedCreateGC;
     pScreen->CloseScreen = pExaScr->SavedCloseScreen;
@@ -1142,6 +1143,8 @@ exaCloseScreen(int i, ScreenPtr pScreen)
 	ps->Composite = pExaScr->SavedComposite;
     }
 #endif
+    if (pExaScr->wrappedEnableDisableFB)
+	pScrn->EnableDisableFBAccess = pExaScr->SavedEnableDisableFBAccess;
 
     xfree (pExaScr);
 
@@ -1152,6 +1155,8 @@ Bool
 exaDriverInit (ScreenPtr		pScreen,
                ExaDriverPtr	pScreenInfo)
 {
+    /* Do NOT use XF86SCRNINFO macro here!! */
+    ScrnInfoPtr pScrn = xf86Screens[pScreen->myNum];
     ExaScreenPrivPtr pExaScr;
 
 #ifdef RENDER
@@ -1165,7 +1170,7 @@ exaDriverInit (ScreenPtr		pScreen,
 	exaGeneration = serverGeneration;
     }
 
-    pExaScr = xalloc (sizeof (ExaScreenPrivRec));
+    pExaScr = xcalloc (sizeof (ExaScreenPrivRec), 1);
 
     if (!pExaScr)
 	return FALSE;
@@ -1233,6 +1238,10 @@ exaDriverInit (ScreenPtr		pScreen,
     if (pExaScr->info->card.offScreenBase < pExaScr->info->card.memorySize) {
 	if (!exaOffscreenInit (pScreen))
             return FALSE;
+
+	pExaScr->SavedEnableDisableFBAccess = pScrn->EnableDisableFBAccess;
+	pScrn->EnableDisableFBAccess = exaEnableDisableFBAccess;
+	pExaScr->wrappedEnableDisableFB = TRUE;
     }
 
     return TRUE;
diff --git a/hw/xfree86/exa/exaPriv.h b/hw/xfree86/exa/exaPriv.h
index 66d0b2faa..6372292e9 100644
--- a/hw/xfree86/exa/exaPriv.h
+++ b/hw/xfree86/exa/exaPriv.h
@@ -44,11 +44,15 @@
 #include "dix.h"
 #include "fb.h"
 #include "fboverlay.h"
+#ifdef RENDER
+#include "fbpict.h"
+#endif
 
 #ifndef EXA_MAX_FB
 #define EXA_MAX_FB   FB_OVERLAY_MAX
 #endif
 
+typedef void (*EnableDisableFBAccessProcPtr)(int, Bool);
 typedef struct {
     ExaDriverPtr info;
     CreateGCProcPtr 		 SavedCreateGC;
@@ -63,6 +67,9 @@ typedef struct {
 #ifdef RENDER
     CompositeProcPtr             SavedComposite;
 #endif
+    EnableDisableFBAccessProcPtr SavedEnableDisableFBAccess;
+    Bool			 wrappedEnableDisableFB;
+    Bool			 swappedOut;
 } ExaScreenPrivRec, *ExaScreenPrivPtr;
 
 /*
@@ -225,6 +232,9 @@ ExaOffscreenSwapIn (ScreenPtr pScreen);
 void
 ExaOffscreenFini (ScreenPtr pScreen);
 
+void
+exaEnableDisableFBAccess (int index, Bool enable);
+
 /* exa.c */
 void
 exaPixmapUseScreen (PixmapPtr pPixmap);
diff --git a/hw/xfree86/exa/exa_accel.c b/hw/xfree86/exa/exa_accel.c
index 49c884595..50550b0a4 100644
--- a/hw/xfree86/exa/exa_accel.c
+++ b/hw/xfree86/exa/exa_accel.c
@@ -331,9 +331,9 @@ exaCreatePixmap(ScreenPtr pScreen, int w, int h, int depth)
     ExaPixmapPrivPtr	pExaPixmap;
     int			bpp;
     ScrnInfoPtr pScrn = XF86SCRNINFO(pScreen);
+    ExaScreenPriv(pScreen);
 
-    if (!pScrn->vtSema) {
-        ExaScreenPriv(pScreen);
+    if (!pScrn->vtSema || pExaScr->swappedOut) {
         pPixmap = pExaScr->SavedCreatePixmap(pScreen, w, h, depth);
     } else {
         bpp = BitsPerPixel (depth);
@@ -1127,6 +1127,7 @@ exaCloseScreen(int i, ScreenPtr pScreen)
 #ifdef RENDER
     PictureScreenPtr	ps = GetPictureScreenIfSet(pScreen);
 #endif
+    ScrnInfoPtr pScrn = XF86SCRNINFO(pScreen);
 
     pScreen->CreateGC = pExaScr->SavedCreateGC;
     pScreen->CloseScreen = pExaScr->SavedCloseScreen;
@@ -1142,6 +1143,8 @@ exaCloseScreen(int i, ScreenPtr pScreen)
 	ps->Composite = pExaScr->SavedComposite;
     }
 #endif
+    if (pExaScr->wrappedEnableDisableFB)
+	pScrn->EnableDisableFBAccess = pExaScr->SavedEnableDisableFBAccess;
 
     xfree (pExaScr);
 
@@ -1152,6 +1155,8 @@ Bool
 exaDriverInit (ScreenPtr		pScreen,
                ExaDriverPtr	pScreenInfo)
 {
+    /* Do NOT use XF86SCRNINFO macro here!! */
+    ScrnInfoPtr pScrn = xf86Screens[pScreen->myNum];
     ExaScreenPrivPtr pExaScr;
 
 #ifdef RENDER
@@ -1165,7 +1170,7 @@ exaDriverInit (ScreenPtr		pScreen,
 	exaGeneration = serverGeneration;
     }
 
-    pExaScr = xalloc (sizeof (ExaScreenPrivRec));
+    pExaScr = xcalloc (sizeof (ExaScreenPrivRec), 1);
 
     if (!pExaScr)
 	return FALSE;
@@ -1233,6 +1238,10 @@ exaDriverInit (ScreenPtr		pScreen,
     if (pExaScr->info->card.offScreenBase < pExaScr->info->card.memorySize) {
 	if (!exaOffscreenInit (pScreen))
             return FALSE;
+
+	pExaScr->SavedEnableDisableFBAccess = pScrn->EnableDisableFBAccess;
+	pScrn->EnableDisableFBAccess = exaEnableDisableFBAccess;
+	pExaScr->wrappedEnableDisableFB = TRUE;
     }
 
     return TRUE;
diff --git a/hw/xfree86/exa/exa_migration.c b/hw/xfree86/exa/exa_migration.c
index 49c884595..50550b0a4 100644
--- a/hw/xfree86/exa/exa_migration.c
+++ b/hw/xfree86/exa/exa_migration.c
@@ -331,9 +331,9 @@ exaCreatePixmap(ScreenPtr pScreen, int w, int h, int depth)
     ExaPixmapPrivPtr	pExaPixmap;
     int			bpp;
     ScrnInfoPtr pScrn = XF86SCRNINFO(pScreen);
+    ExaScreenPriv(pScreen);
 
-    if (!pScrn->vtSema) {
-        ExaScreenPriv(pScreen);
+    if (!pScrn->vtSema || pExaScr->swappedOut) {
         pPixmap = pExaScr->SavedCreatePixmap(pScreen, w, h, depth);
     } else {
         bpp = BitsPerPixel (depth);
@@ -1127,6 +1127,7 @@ exaCloseScreen(int i, ScreenPtr pScreen)
 #ifdef RENDER
     PictureScreenPtr	ps = GetPictureScreenIfSet(pScreen);
 #endif
+    ScrnInfoPtr pScrn = XF86SCRNINFO(pScreen);
 
     pScreen->CreateGC = pExaScr->SavedCreateGC;
     pScreen->CloseScreen = pExaScr->SavedCloseScreen;
@@ -1142,6 +1143,8 @@ exaCloseScreen(int i, ScreenPtr pScreen)
 	ps->Composite = pExaScr->SavedComposite;
     }
 #endif
+    if (pExaScr->wrappedEnableDisableFB)
+	pScrn->EnableDisableFBAccess = pExaScr->SavedEnableDisableFBAccess;
 
     xfree (pExaScr);
 
@@ -1152,6 +1155,8 @@ Bool
 exaDriverInit (ScreenPtr		pScreen,
                ExaDriverPtr	pScreenInfo)
 {
+    /* Do NOT use XF86SCRNINFO macro here!! */
+    ScrnInfoPtr pScrn = xf86Screens[pScreen->myNum];
     ExaScreenPrivPtr pExaScr;
 
 #ifdef RENDER
@@ -1165,7 +1170,7 @@ exaDriverInit (ScreenPtr		pScreen,
 	exaGeneration = serverGeneration;
     }
 
-    pExaScr = xalloc (sizeof (ExaScreenPrivRec));
+    pExaScr = xcalloc (sizeof (ExaScreenPrivRec), 1);
 
     if (!pExaScr)
 	return FALSE;
@@ -1233,6 +1238,10 @@ exaDriverInit (ScreenPtr		pScreen,
     if (pExaScr->info->card.offScreenBase < pExaScr->info->card.memorySize) {
 	if (!exaOffscreenInit (pScreen))
             return FALSE;
+
+	pExaScr->SavedEnableDisableFBAccess = pScrn->EnableDisableFBAccess;
+	pScrn->EnableDisableFBAccess = exaEnableDisableFBAccess;
+	pExaScr->wrappedEnableDisableFB = TRUE;
     }
 
     return TRUE;
diff --git a/hw/xfree86/exa/exa_offscreen.c b/hw/xfree86/exa/exa_offscreen.c
index d62db9016..6b1a160ed 100644
--- a/hw/xfree86/exa/exa_offscreen.c
+++ b/hw/xfree86/exa/exa_offscreen.c
@@ -253,6 +253,26 @@ ExaOffscreenSwapIn (ScreenPtr pScreen)
     exaOffscreenInit (pScreen);
 }
 
+void
+exaEnableDisableFBAccess (int index, Bool enable)
+{
+    ScreenPtr pScreen = screenInfo.screens[index];
+    ExaScreenPriv (pScreen);
+
+    if (!enable) {
+	ExaOffscreenSwapOut (pScreen);
+	pExaScr->swappedOut = TRUE;
+    }
+
+    if (pExaScr->SavedEnableDisableFBAccess)
+       (*pExaScr->SavedEnableDisableFBAccess)(index, enable);
+
+    if (enable) {
+	ExaOffscreenSwapIn (pScreen);
+	pExaScr->swappedOut = FALSE;
+    }
+}
+
 /* merge the next free area into this one */
 static void
 ExaOffscreenMerge (ExaOffscreenArea *area)
diff --git a/hw/xfree86/exa/exa_priv.h b/hw/xfree86/exa/exa_priv.h
index 66d0b2faa..6372292e9 100644
--- a/hw/xfree86/exa/exa_priv.h
+++ b/hw/xfree86/exa/exa_priv.h
@@ -44,11 +44,15 @@
 #include "dix.h"
 #include "fb.h"
 #include "fboverlay.h"
+#ifdef RENDER
+#include "fbpict.h"
+#endif
 
 #ifndef EXA_MAX_FB
 #define EXA_MAX_FB   FB_OVERLAY_MAX
 #endif
 
+typedef void (*EnableDisableFBAccessProcPtr)(int, Bool);
 typedef struct {
     ExaDriverPtr info;
     CreateGCProcPtr 		 SavedCreateGC;
@@ -63,6 +67,9 @@ typedef struct {
 #ifdef RENDER
     CompositeProcPtr             SavedComposite;
 #endif
+    EnableDisableFBAccessProcPtr SavedEnableDisableFBAccess;
+    Bool			 wrappedEnableDisableFB;
+    Bool			 swappedOut;
 } ExaScreenPrivRec, *ExaScreenPrivPtr;
 
 /*
@@ -225,6 +232,9 @@ ExaOffscreenSwapIn (ScreenPtr pScreen);
 void
 ExaOffscreenFini (ScreenPtr pScreen);
 
+void
+exaEnableDisableFBAccess (int index, Bool enable);
+
 /* exa.c */
 void
 exaPixmapUseScreen (PixmapPtr pPixmap);
diff --git a/hw/xfree86/exa/exaoffscreen.c b/hw/xfree86/exa/exaoffscreen.c
index d62db9016..6b1a160ed 100644
--- a/hw/xfree86/exa/exaoffscreen.c
+++ b/hw/xfree86/exa/exaoffscreen.c
@@ -253,6 +253,26 @@ ExaOffscreenSwapIn (ScreenPtr pScreen)
     exaOffscreenInit (pScreen);
 }
 
+void
+exaEnableDisableFBAccess (int index, Bool enable)
+{
+    ScreenPtr pScreen = screenInfo.screens[index];
+    ExaScreenPriv (pScreen);
+
+    if (!enable) {
+	ExaOffscreenSwapOut (pScreen);
+	pExaScr->swappedOut = TRUE;
+    }
+
+    if (pExaScr->SavedEnableDisableFBAccess)
+       (*pExaScr->SavedEnableDisableFBAccess)(index, enable);
+
+    if (enable) {
+	ExaOffscreenSwapIn (pScreen);
+	pExaScr->swappedOut = FALSE;
+    }
+}
+
 /* merge the next free area into this one */
 static void
 ExaOffscreenMerge (ExaOffscreenArea *area)