[patch] exa: fix pitch handling in ModifyPixmapHeader

[Zhenyu Wang]

https://bugs.freedesktop.org/show_bug.cgi?id=15509

The issue is seen when large virtual screen set and do rotation.
Rotate shadow pixmap got large pitch which exceed hw limit (8k),
I tried to set maxPitchPixel/Bytes but it still failed to guard for
me.

The problem is current exaModifyPixmapHeader totally ignores
'devKind', and exaSetAccelBlock only looks exa pixmap private fb_pitch,
which is not available for home-made pixmap like rotate_pixmap.
Following patch trys to fix case like this.

---
diff --git a/exa/exa.c b/exa/exa.c
index 81dc3e2..3369c3a 100644
--- a/exa/exa.c
+++ b/exa/exa.c
@@ -386,6 +386,9 @@ exaModifyPixmapHeader(PixmapPtr pPixmap, int width, int height, int depth,
     if (pExaPixmap) {
 	pExaPixmap->sys_ptr = pPixData;
 
+	if (pExaPixmap->fb_pitch == 0)
+	    pExaPixmap->fb_pitch = devKind;
+
         exaSetAccelBlock(pExaScr, pExaPixmap,
                          width, height, bitsPerPixel);
     }
-- 
Open Source Technology Center, Intel ltd.

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