[PATCH] exa: fix gnome-panel corruption

[Maarten Maathuis]

- A mapped pixmap can't be used for acceleration, any decent memory manager
will refuse this.
- Source pixmaps may need updating, so move in the pixmap unconditionally, it
should be a no-op in most cases anyway.

Signed-off-by: Maarten Maathuis <madman2003 at gmail.com>
---
 exa/exa_migration_mixed.c |   18 ++++++++++++------
 1 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/exa/exa_migration_mixed.c b/exa/exa_migration_mixed.c
index 6816e6c..77b2b2b 100644
--- a/exa/exa_migration_mixed.c
+++ b/exa/exa_migration_mixed.c
@@ -167,9 +167,12 @@ exaPrepareAccessReg_mixed(PixmapPtr pPixmap, int index, RegionPtr pReg)
     ExaPixmapPriv(pPixmap);
 
     if (!ExaDoPrepareAccess(pPixmap, index)) {
-	Bool has_gpu_copy = exaPixmapHasGpuCopy(pPixmap);
+	Bool has_gpu_copy;
 	ExaMigrationRec pixmaps[1];
 
+late_failure:
+	has_gpu_copy = exaPixmapHasGpuCopy(pPixmap);
+
 	/* Do we need to allocate our system buffer? */
 	if (!pExaPixmap->sys_ptr) {
 	    pExaPixmap->sys_ptr = malloc(pExaPixmap->sys_pitch *
@@ -231,12 +234,15 @@ exaPrepareAccessReg_mixed(PixmapPtr pPixmap, int index, RegionPtr pReg)
     /* We have a gpu pixmap that can be accessed, we don't need the cpu copy
      * anymore. Drivers that prefer DFS, should fail prepare access. */
     } else if (pExaPixmap->pDamage && exaPixmapHasGpuCopy(pPixmap)) {
-	ExaScreenPriv(pPixmap->drawable.pScreen);
 
-	/* Copy back any deferred content if needed. */
-	if (pExaScr->deferred_mixed_pixmap &&
-	    pExaScr->deferred_mixed_pixmap == pPixmap)
-	    exaMoveInPixmap_mixed(pPixmap);
+	/* You cannot do accelerated operations while a buffer is mapped. */
+	exaFinishAccess(&pPixmap->drawable, index);
+	/* Sources with pReg are not fully in the gpu pixmap yet, as well
+	 * as deferred destination pixmaps.
+	 */
+	exaMoveInPixmap_mixed(pPixmap);
+	if (!ExaDoPrepareAccess(pPixmap, index))
+	    goto late_failure;
 
 	DamageUnregister(&pPixmap->drawable, pExaPixmap->pDamage);
 	DamageDestroy(pExaPixmap->pDamage);
-- 
1.6.6.1