[PATCH] DRI2: Add ReuseBufferNotify hook

[Pauli Nieminen]

ReuseBufferNotify hook is called whenever old buffer is reused in DRI2
code.

Driver can use this hook to rewrite the buffer name if hardware requires
shared buffers. Shared buffer might be some hardware limited resources like
framebuffer that is preallocated in boot.

Signed-off-by: Pauli Nieminen <ext-pauli.nieminen at nokia.com>
---
 hw/xfree86/dri2/dri2.c |    9 +++++++++
 hw/xfree86/dri2/dri2.h |   16 +++++++++++++++-
 2 files changed, 24 insertions(+), 1 deletions(-)

diff --git a/hw/xfree86/dri2/dri2.c b/hw/xfree86/dri2/dri2.c
index c96eb35..228c0e0 100644
--- a/hw/xfree86/dri2/dri2.c
+++ b/hw/xfree86/dri2/dri2.c
@@ -101,6 +101,7 @@ typedef struct _DRI2Screen {
     DRI2GetMSCProcPtr		 GetMSC;
     DRI2ScheduleWaitMSCProcPtr	 ScheduleWaitMSC;
     DRI2AuthMagicProcPtr	 AuthMagic;
+    DRI2ReuseBufferNotifyProcPtr   ReuseBufferNotify;
 
     HandleExposuresProcPtr       HandleExposures;
 
@@ -369,6 +370,10 @@ allocate_or_reuse_buffer(DrawablePtr pDraw, DRI2ScreenPtr ds,
 
     } else {
 	*buffer = pPriv->buffers[old_buf];
+
+	if (ds->ReuseBufferNotify)
+		(*ds->ReuseBufferNotify)(pDraw, *buffer);
+
 	pPriv->buffers[old_buf] = NULL;
 	return FALSE;
     }
@@ -1123,6 +1128,10 @@ DRI2ScreenInit(ScreenPtr pScreen, DRI2InfoPtr info)
         ds->AuthMagic = info->AuthMagic;
     }
 
+    if (info->version >= 6) {
+	ds->ReuseBufferNotify = info->ReuseBufferNotify;
+    }
+
     /*
      * if the driver doesn't provide an AuthMagic function or the info struct
      * version is too low, it relies on the old method (using libdrm) or fail
diff --git a/hw/xfree86/dri2/dri2.h b/hw/xfree86/dri2/dri2.h
index 0e0bea4..3d01c55 100644
--- a/hw/xfree86/dri2/dri2.h
+++ b/hw/xfree86/dri2/dri2.h
@@ -110,6 +110,16 @@ typedef DRI2BufferPtr	(*DRI2CreateBufferProcPtr)(DrawablePtr pDraw,
 typedef void		(*DRI2DestroyBufferProcPtr)(DrawablePtr pDraw,
 						    DRI2BufferPtr buffer);
 /**
+ * Notifies driver when DRI2GetBuffers reuses a dri2 buffer.
+ *
+ * Driver may rename the dri2 buffer in this notify if it is required.
+ *
+ * \param pDraw drawable whose count we want
+ * \param buffer buffer that will be returned to client
+ */
+typedef void		(*DRI2ReuseBufferNotifyProcPtr)(DrawablePtr pDraw,
+						      DRI2BufferPtr buffer);
+/**
  * Get current media stamp counter values
  *
  * This callback is used to support the SGI_video_sync and OML_sync_control
@@ -161,7 +171,7 @@ typedef void		(*DRI2InvalidateProcPtr)(DrawablePtr pDraw,
 /**
  * Version of the DRI2InfoRec structure defined in this header
  */
-#define DRI2INFOREC_VERSION 5
+#define DRI2INFOREC_VERSION 6
 
 typedef struct {
     unsigned int version;	/**< Version of this struct */
@@ -189,6 +199,10 @@ typedef struct {
     /* added in version 5 */
 
     DRI2AuthMagicProcPtr	AuthMagic;
+
+    /* added in version 6 */
+
+    DRI2ReuseBufferNotifyProcPtr ReuseBufferNotify;
 }  DRI2InfoRec, *DRI2InfoPtr;
 
 extern _X_EXPORT int DRI2EventBase;
-- 
1.7.0.4