[PATCH] Fallback to std DRI2CopyRegion when DRI2UpdatePrime fails

[Chris Wilson]

I was looking at a bug report today of intel/ati prime and noticed a
number of sna_share_pixmap_backing() failures (called from
DRI2UpdatePrime). These were failing as the request was for the scanout
buffer (which is tiled and so we refuse to share it, and since it is
already on the scanout we refuse to change tiling).

But looking at radeon_dri2_copy_region2(), if DRI2UpdatePrime() fails,
the copy is aborted and the update lost. If the copy is made to the
normal window drawable is that enough for it to be propagated back
through damage tracking?
---
 src/radeon_dri2.c | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/src/radeon_dri2.c b/src/radeon_dri2.c
index 9a9918b..0d113b9 100644
--- a/src/radeon_dri2.c
+++ b/src/radeon_dri2.c
@@ -409,26 +409,27 @@ radeon_dri2_copy_region2(ScreenPtr pScreen,
     dst_drawable = &dst_private->pixmap->drawable;
 
     if (src_private->attachment == DRI2BufferFrontLeft) {
+	src_drawable = NULL;
 #ifdef USE_DRI2_PRIME
-	if (drawable->pScreen != pScreen) {
+	if (drawable->pScreen != pScreen)
 	    src_drawable = DRI2UpdatePrime(drawable, src_buffer);
-	    if (!src_drawable)
-		return;
-	} else
 #endif
+	if (src_drawable == NULL)
 	    src_drawable = drawable;
     }
     if (dst_private->attachment == DRI2BufferFrontLeft) {
+	dst_drawable = NULL;
 #ifdef USE_DRI2_PRIME
 	if (drawable->pScreen != pScreen) {
 	    dst_drawable = DRI2UpdatePrime(drawable, dest_buffer);
-	    if (!dst_drawable)
-		return;
-	    dst_ppix = (PixmapPtr)dst_drawable;
-	    if (dst_drawable != drawable)
-		translate = TRUE;
-	} else
+	    if (dst_drawable) {
+		dst_ppix = (PixmapPtr)dst_drawable;
+		if (dst_drawable != drawable)
+		    translate = TRUE;
+	    }
+	}
 #endif
+	if (dst_drawable == NULL)
 	    dst_drawable = drawable;
     }
 
-- 
2.1.1