[Intel-gfx] [PATCH] Check display stride limit when allocate front buffer

[Zhenyu Wang]

Subject: [PATCH] Check display stride limit when allocate front buffer

---
 src/i830_memory.c |   27 +++++++++++++++++++++++++++
 1 files changed, 27 insertions(+), 0 deletions(-)

diff --git a/src/i830_memory.c b/src/i830_memory.c
index 443cc4e..2119012 100644
--- a/src/i830_memory.c
+++ b/src/i830_memory.c
@@ -158,6 +158,27 @@ i830_get_fence_size(ScrnInfoPtr pScrn, unsigned long size)
 }
 
 static Bool
+i830_display_stride_ok(ScrnInfoPtr pScrn, int stride, Bool tiling)
+{
+    I830Ptr pI830 = I830PTR(pScrn);
+    int limit = KB(32);
+
+    if ((IS_845G(pI830) || IS_I85X(pI830)) && tiling)
+	limit = KB(8);
+
+    if (IS_I915(pI830) && tiling)
+	limit = KB(8);
+
+    if (IS_I965G(pI830) && tiling)
+	limit = KB(16);
+
+    if (stride <= limit)
+	return TRUE;
+    else
+	return FALSE;
+}
+
+static Bool
 i830_bind_memory(ScrnInfoPtr pScrn, i830_memory *mem)
 {
     I830Ptr pI830 = I830PTR(pScrn);
@@ -1200,6 +1221,12 @@ i830_allocate_framebuffer(ScrnInfoPtr pScrn, I830Ptr pI830, BoxPtr FbMemBox,
     else
 	tiling = pI830->tiling;
 
+    if (!i830_display_stride_ok(pScrn, pitch, tiling)) {
+	xf86DrvMsg(pScrn->scrnIndex, X_ERROR, "Front buffer stride %d kB "
+		"exceed display limit\n", pitch/1024);
+	return NULL;
+    }
+
     /* Attempt to allocate it tiled first if we have page flipping on. */
     if (tiling && IsTileable(pScrn, pitch)) {
 	/* XXX: probably not the case on 965 */
-- 
1.5.6.5

-- 
Open Source Technology Center, Intel ltd.

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