Move swap_interval to new extension mechanism.

19 files changed, 114 insertions, 52 deletions

diff --git a/include/GL/internal/dri_interface.h b/include/GL/internal/dri_interface.h
index e2050c16b4f..7eb168a1b90 100644
--- a/include/GL/internal/dri_interface.h
+++ b/include/GL/internal/dri_interface.h
@@ -59,6 +59,7 @@ typedef struct __DRIinterfaceMethodsRec	__DRIinterfaceMethods;
 
 typedef struct __DRIextensionRec	__DRIextension;
 typedef struct __DRIcopySubBufferExtensionRec	__DRIcopySubBufferExtension;
+typedef struct __DRIswapControlExtensionRec	__DRIswapControlExtension;
 /*@}*/
 
 
@@ -83,6 +84,16 @@ struct __DRIcopySubBufferExtensionRec {
     void (*copySubBuffer)(__DRIdrawable *drawable, int x, int y, int w, int h);
 };
 
+/**
+ * Used by drivers that implement the GLX_SGI_swap_control or
+ * GLX_MESA_swap_control extension.
+ */
+#define __DRI_SWAP_CONTROL "DRI_SwapControl"
+struct __DRIswapControlExtensionRec {
+    __DRIextension base;
+    void (*setSwapInterval)(__DRIdrawable *drawable, unsigned int inteval);
+    unsigned int (*getSwapInterval)(__DRIdrawable *drawable);
+};
 
 /**
  * \name Functions provided by the driver loader.
@@ -483,14 +494,6 @@ struct __DRIdrawableRec {
     int (*queryFrameTracking)(__DRIdrawable *drawable,
 			      int64_t * sbc, int64_t * missedFrames,
 			      float * lastMissedUsage, float * usage);
-
-    /**
-     * Used by drivers that implement the GLX_SGI_swap_control or
-     * GLX_MESA_swap_control extension.
-     *
-     * \since Internal API version 20030317.
-     */
-    unsigned swap_interval;
 };
 
 #endif
diff --git a/src/glx/x11/glxclient.h b/src/glx/x11/glxclient.h
index 2c730282397..09ae70212ac 100644
--- a/src/glx/x11/glxclient.h
+++ b/src/glx/x11/glxclient.h
@@ -481,6 +481,10 @@ struct __GLXscreenConfigsRec {
     __DRIcopySubBufferExtension *copySubBuffer;
 #endif
 
+#ifdef __DRI_SWAP_CONTROL
+    __DRIswapControlExtension *swapControl;
+#endif
+
 #endif
 
     /**
diff --git a/src/glx/x11/glxcmds.c b/src/glx/x11/glxcmds.c
index 1bc5fff957c..6fda5125db7 100644
--- a/src/glx/x11/glxcmds.c
+++ b/src/glx/x11/glxcmds.c
@@ -1731,16 +1731,15 @@ static int __glXSwapIntervalSGI(int interval)
       return GLX_BAD_VALUE;
    }
 
-#ifdef GLX_DIRECT_RENDERING
+#ifdef __DRI_SWAP_CONTROL
    if ( gc->isDirect ) {
        __GLXscreenConfigs * const psc = GetGLXScreenConfigs( gc->currentDpy,
 							     gc->screen );
        __DRIdrawable * const pdraw = GetDRIDrawable( gc->currentDpy,
 						     gc->currentDrawable,
 						     NULL );
-       if ( __glXExtensionBitIsEnabled( psc, SGI_swap_control_bit )
-	    && (pdraw != NULL) ) {
-	   pdraw->swap_interval = interval;
+       if (psc->swapControl != NULL && pdraw != NULL) {
+	   psc->swapControl->setSwapInterval(pdraw, interval);
 	   return 0;
        }
        else {
@@ -1778,7 +1777,7 @@ static int __glXSwapIntervalSGI(int interval)
 */
 static int __glXSwapIntervalMESA(unsigned int interval)
 {
-#ifdef GLX_DIRECT_RENDERING
+#ifdef __DRI_SWAP_CONTROL
    GLXContext gc = __glXGetCurrentContext();
 
    if ( interval < 0 ) {
@@ -1789,12 +1788,11 @@ static int __glXSwapIntervalMESA(unsigned int interval)
       __GLXscreenConfigs * const psc = GetGLXScreenConfigs( gc->currentDpy,
 							    gc->screen );
       
-      if ( (psc != NULL) && (psc->driScreen.private != NULL)
-	   && __glXExtensionBitIsEnabled( psc, MESA_swap_control_bit ) ) {
+      if ( (psc != NULL) && (psc->driScreen.private != NULL) ) {
 	 __DRIdrawable * const pdraw = 
 	     GetDRIDrawable(gc->currentDpy, gc->currentDrawable, NULL);
-	 if ( pdraw != NULL ) {
-	    pdraw->swap_interval = interval;
+	 if (psc->swapControl != NULL && pdraw != NULL) {
+	    psc->swapControl->setSwapInterval(pdraw, interval);
 	    return 0;
 	 }
       }
@@ -1809,19 +1807,18 @@ static int __glXSwapIntervalMESA(unsigned int interval)
 
 static int __glXGetSwapIntervalMESA(void)
 {
-#ifdef GLX_DIRECT_RENDERING
+#ifdef __DRI_SWAP_CONTROL
    GLXContext gc = __glXGetCurrentContext();
 
    if ( (gc != NULL) && gc->isDirect ) {
       __GLXscreenConfigs * const psc = GetGLXScreenConfigs( gc->currentDpy,
 							    gc->screen );
       
-      if ( (psc != NULL) && (psc->driScreen.private != NULL)
-	   && __glXExtensionBitIsEnabled( psc, MESA_swap_control_bit ) ) {
+      if ( (psc != NULL) && (psc->driScreen.private != NULL) ) {
 	 __DRIdrawable * const pdraw = 
 	     GetDRIDrawable(gc->currentDpy, gc->currentDrawable, NULL);
-	 if ( pdraw != NULL ) {
-	    return pdraw->swap_interval;
+	 if (psc->swapControl != NULL && pdraw != NULL) {
+	    return psc->swapControl->getSwapInterval(pdraw);
 	 }
       }
    }
diff --git a/src/glx/x11/glxext.c b/src/glx/x11/glxext.c
index d0a7a64445a..1563ca63943 100644
--- a/src/glx/x11/glxext.c
+++ b/src/glx/x11/glxext.c
@@ -1027,6 +1027,18 @@ static void queryExtensions(__GLXscreenConfigs *psc)
 	    
 	}
 #endif
+
+#ifdef __DRI_SWAP_CONTROL
+	if (strcmp(extensions[i]->name, __DRI_SWAP_CONTROL) == 0) {
+	    psc->swapControl = (__DRIswapControlExtension *) extensions[i];
+	    __glXScrEnableExtension(&psc->driScreen,
+				    "GLX_SGI_swap_control");
+	    __glXScrEnableExtension(&psc->driScreen,
+				    "GLX_MESA_swap_control");
+	    
+	}
+#endif
+
 	/* Ignore unknown extensions */
     }
 }
diff --git a/src/mesa/drivers/dri/common/dri_util.c b/src/mesa/drivers/dri/common/dri_util.c
index fc7755797d6..ba677f6ff86 100644
--- a/src/mesa/drivers/dri/common/dri_util.c
+++ b/src/mesa/drivers/dri/common/dri_util.c
@@ -435,6 +435,27 @@ const __DRIcopySubBufferExtension driCopySubBufferExtension = {
     { __DRI_COPY_SUB_BUFFER }, driCopySubBuffer
 };
 
+static void driSetSwapInterval(__DRIdrawable *drawable, unsigned int interval)
+{
+    __DRIdrawablePrivate *dpriv = drawable->private;
+
+    dpriv->swap_interval = interval;
+}
+
+static unsigned int driGetSwapInterval(__DRIdrawable *drawable)
+{
+    __DRIdrawablePrivate *dpriv = drawable->private;
+
+    return dpriv->swap_interval;
+}
+
+const __DRIswapControlExtension driSwapControlExtension = {
+    { __DRI_SWAP_CONTROL },
+    driSetSwapInterval,
+    driGetSwapInterval
+};
+
+
 /**
  * This is called via __DRIscreenRec's createNewDrawable pointer.
  */
@@ -501,7 +522,7 @@ static void *driCreateNewDrawable(__DRIscreen *screen,
      * default value when the drawable is first bound to a direct
      * rendering context. 
      */
-    pdraw->swap_interval = (unsigned)-1;
+    pdp->swap_interval = (unsigned)-1;
 
     pdp->swapBuffers = psp->DriverAPI.SwapBuffers;
 
@@ -716,7 +737,7 @@ void * __DRI_CREATE_NEW_SCREEN( int scrn, __DRIscreen *psc,
 			     
 {
     __DRIscreenPrivate *psp;
-    static const __DRIextension emptyExtensionList[] = { NULL };
+    static const __DRIextension *emptyExtensionList[] = { NULL };
     dri_interface = interface;
     api_ver = internal_api_version;
 
@@ -868,8 +889,7 @@ driCalculateSwapUsage( __DRIdrawablePrivate *dPriv, int64_t last_swap_ust,
 
 
    if ( (*dri_interface->getMSCRate)(dPriv->pdraw, &n, &d) ) {
-      interval = (dPriv->pdraw->swap_interval != 0)
-	  ? dPriv->pdraw->swap_interval : 1;
+      interval = (dPriv->swap_interval != 0) ? dPriv->swap_interval : 1;
 
 
       /* We want to calculate
diff --git a/src/mesa/drivers/dri/common/dri_util.h b/src/mesa/drivers/dri/common/dri_util.h
index 59bb66d21bc..78320307d60 100644
--- a/src/mesa/drivers/dri/common/dri_util.h
+++ b/src/mesa/drivers/dri/common/dri_util.h
@@ -77,6 +77,7 @@ extern __GLcontextModes *__driDriverInitScreen(__DRIscreenPrivate *psp);
  * Extensions.
  */
 extern const __DRIcopySubBufferExtension driCopySubBufferExtension;
+extern const __DRIswapControlExtension driSwapControlExtension;
 
 /**
  * Used by DRI_VALIDATE_DRAWABLE_INFO
@@ -327,6 +328,12 @@ struct __DRIdrawablePrivateRec {
      * Called via glXSwapBuffers().
      */
     void (*swapBuffers)( __DRIdrawablePrivate *dPriv );
+
+    /**
+     * Controls swap interval as used by GLX_SGI_swap_control and
+     * GLX_MESA_swap_control.
+     */
+    unsigned int swap_interval;
 };
 
 /**
diff --git a/src/mesa/drivers/dri/common/vblank.c b/src/mesa/drivers/dri/common/vblank.c
index e7ed545f13c..3b5acfecb12 100644
--- a/src/mesa/drivers/dri/common/vblank.c
+++ b/src/mesa/drivers/dri/common/vblank.c
@@ -255,13 +255,13 @@ static int do_wait( drmVBlank * vbl, GLuint * vbl_seq, int fd )
 void driDrawableInitVBlank( __DRIdrawablePrivate *priv, GLuint flags,
 			    GLuint *vbl_seq )
 {
-   if ( priv->pdraw->swap_interval == (unsigned)-1 ) {
+   if ( priv->swap_interval == (unsigned)-1 ) {
       /* Get current vertical blank sequence */
       drmVBlank vbl = { .request={ .type = DRM_VBLANK_RELATIVE, .sequence = 0 } };
       do_wait( &vbl, vbl_seq, priv->driScreenPriv->fd );
 
-      priv->pdraw->swap_interval = (flags & (VBLANK_FLAG_THROTTLE |
-					     VBLANK_FLAG_SYNC)) != 0 ? 1 : 0;
+      priv->swap_interval = (flags & (VBLANK_FLAG_THROTTLE |
+				      VBLANK_FLAG_SYNC)) != 0 ? 1 : 0;
    }
 }
 
@@ -277,9 +277,9 @@ driGetVBlankInterval( const  __DRIdrawablePrivate *priv, GLuint flags )
    if ( (flags & VBLANK_FLAG_INTERVAL) != 0 ) {
       /* this must have been initialized when the drawable was first bound
        * to a direct rendering context. */
-      assert ( priv->pdraw->swap_interval != (unsigned)-1 );
+      assert ( priv->swap_interval != (unsigned)-1 );
 
-      return priv->pdraw->swap_interval;
+      return priv->swap_interval;
    }
    else if ( (flags & (VBLANK_FLAG_THROTTLE | VBLANK_FLAG_SYNC)) != 0 ) {
       return 1;
diff --git a/src/mesa/drivers/dri/i915/intel_context.c b/src/mesa/drivers/dri/i915/intel_context.c
index 041a155fe73..d7af432ad6b 100644
--- a/src/mesa/drivers/dri/i915/intel_context.c
+++ b/src/mesa/drivers/dri/i915/intel_context.c
@@ -613,7 +613,7 @@ intelMakeCurrent(__DRIcontextPrivate * driContextPriv,
       if (intel->ctx.DrawBuffer == &intel_fb->Base) {
 
 	 if (intel->driDrawable != driDrawPriv) {
-	    if (driDrawPriv->pdraw->swap_interval == (unsigned)-1) {
+	    if (driDrawPriv->swap_interval == (unsigned)-1) {
 	       int i;
 
 	       intel_fb->vblank_flags = (intel->intelScreen->irq_active != 0)
diff --git a/src/mesa/drivers/dri/i915/intel_screen.c b/src/mesa/drivers/dri/i915/intel_screen.c
index 792f26b5ed4..f507a3bf05f 100644
--- a/src/mesa/drivers/dri/i915/intel_screen.c
+++ b/src/mesa/drivers/dri/i915/intel_screen.c
@@ -421,6 +421,7 @@ intelUpdateScreenFromSAREA(intelScreenPrivate * intelScreen,
 
 static const __DRIextension *intelExtensions[] = {
     &driCopySubBufferExtension.base,
+    &driSwapControlExtension.base,
     NULL
 };
 
@@ -529,9 +530,7 @@ static GLboolean intelInitDriver(__DRIscreenPrivate *sPriv)
    sPriv->extensions = intelExtensions;
 
    if (glx_enable_extension != NULL) {
-      (*glx_enable_extension) (sPriv->psc, "GLX_SGI_swap_control");
       (*glx_enable_extension) (sPriv->psc, "GLX_SGI_video_sync");
-      (*glx_enable_extension) (sPriv->psc, "GLX_MESA_swap_control");
       (*glx_enable_extension) (sPriv->psc, "GLX_MESA_swap_frame_usage");
       (*glx_enable_extension) (sPriv->psc, "GLX_SGI_make_current_read");
    }
diff --git a/src/mesa/drivers/dri/i965/intel_screen.c b/src/mesa/drivers/dri/i965/intel_screen.c
index 1f74103f651..c75a86bf5b2 100644
--- a/src/mesa/drivers/dri/i965/intel_screen.c
+++ b/src/mesa/drivers/dri/i965/intel_screen.c
@@ -266,6 +266,7 @@ intelUpdateScreenFromSAREA(intelScreenPrivate *intelScreen,
 
 static const __DRIextension *intelExtensions[] = {
     &driCopySubBufferExtension.base,
+    &driSwapControlExtension.base,
     NULL
 };
 
@@ -357,9 +358,7 @@ static GLboolean intelInitDriver(__DRIscreenPrivate *sPriv)
    sPriv->extensions = intelExtensions;
 
    if (glx_enable_extension != NULL) {
-      (*glx_enable_extension)( sPriv->psc, "GLX_SGI_swap_control" );
       (*glx_enable_extension)( sPriv->psc, "GLX_SGI_video_sync" );
-      (*glx_enable_extension)( sPriv->psc, "GLX_MESA_swap_control" );
       (*glx_enable_extension)( sPriv->psc, "GLX_MESA_swap_frame_usage" );
       (*glx_enable_extension)( sPriv->psc, "GLX_SGI_make_current_read" );
    }
diff --git a/src/mesa/drivers/dri/mach64/mach64_screen.c b/src/mesa/drivers/dri/mach64/mach64_screen.c
index ff261c841d7..46314b426f7 100644
--- a/src/mesa/drivers/dri/mach64/mach64_screen.c
+++ b/src/mesa/drivers/dri/mach64/mach64_screen.c
@@ -210,6 +210,7 @@ mach64CreateScreen( __DRIscreenPrivate *sPriv )
    ATIDRIPtr serverInfo = (ATIDRIPtr)sPriv->pDevPriv;
    PFNGLXSCRENABLEEXTENSIONPROC glx_enable_extension =
      (PFNGLXSCRENABLEEXTENSIONPROC) (*dri_interface->getProcAddress("glxEnableExtension"));
+   int i;
 
    if (sPriv->devPrivSize != sizeof(ATIDRIRec)) {
       fprintf(stderr,"\nERROR!  sizeof(ATIDRIRec) does not match passed size from device driver\n");
@@ -318,15 +319,18 @@ mach64CreateScreen( __DRIscreenPrivate *sPriv )
 
    mach64Screen->driScreen = sPriv;
 
+   i = 0;
    if ( glx_enable_extension != NULL ) {
       if ( mach64Screen->irq != 0 ) {
-	 (*glx_enable_extension)( sPriv->psc, "GLX_SGI_swap_control" );
+	 mach64Screen->extensions[i++] = &driSwapControlExtension.base;
+
 	 (*glx_enable_extension)( sPriv->psc, "GLX_SGI_video_sync" );
-	 (*glx_enable_extension)( sPriv->psc, "GLX_MESA_swap_control" );
       }
 
       (*glx_enable_extension)( sPriv->psc, "GLX_MESA_swap_frame_usage" );
    }
+   mach64Screen->extensions[i++] = NULL;
+   sPriv->extensions = mach64Screen->extensions;
 
    return mach64Screen;
 }
diff --git a/src/mesa/drivers/dri/mach64/mach64_screen.h b/src/mesa/drivers/dri/mach64/mach64_screen.h
index 5305058e2fb..36da7157707 100644
--- a/src/mesa/drivers/dri/mach64/mach64_screen.h
+++ b/src/mesa/drivers/dri/mach64/mach64_screen.h
@@ -73,6 +73,8 @@ typedef struct {
    __DRIscreenPrivate *driScreen;
 
    driOptionCache optionCache;
+
+   const __DRIextension *extensions[2];
 } mach64ScreenRec, *mach64ScreenPtr;
 
 #endif /* __MACH64_SCREEN_H__ */
diff --git a/src/mesa/drivers/dri/mga/mga_xmesa.c b/src/mesa/drivers/dri/mga/mga_xmesa.c
index 5b4693983af..eba96486f67 100644
--- a/src/mesa/drivers/dri/mga/mga_xmesa.c
+++ b/src/mesa/drivers/dri/mga/mga_xmesa.c
@@ -193,6 +193,11 @@ mgaFillInModes( unsigned pixel_bits, unsigned depth_bits,
 }
 
 
+static const __DRIextension *mgaExtensions[] = {
+    &driSwapControlExtension.base,
+    NULL
+};
+
 static GLboolean
 mgaInitDriver(__DRIscreenPrivate *sPriv)
 {
@@ -234,11 +239,11 @@ mgaInitDriver(__DRIscreenPrivate *sPriv)
       }
    }
 
+   sPriv->extensions = mgaExtensions;
+
    if ( glx_enable_extension != NULL ) {
-      (*glx_enable_extension)( sPriv->psc, "GLX_MESA_swap_control" );
       (*glx_enable_extension)( sPriv->psc, "GLX_MESA_swap_frame_usage" );
       (*glx_enable_extension)( sPriv->psc, "GLX_SGI_make_current_read" );
-      (*glx_enable_extension)( sPriv->psc, "GLX_SGI_swap_control" );
       (*glx_enable_extension)( sPriv->psc, "GLX_SGI_video_sync" );
    }
 
diff --git a/src/mesa/drivers/dri/r128/r128_screen.c b/src/mesa/drivers/dri/r128/r128_screen.c
index 446280c399f..9e5c25d7207 100644
--- a/src/mesa/drivers/dri/r128/r128_screen.c
+++ b/src/mesa/drivers/dri/r128/r128_screen.c
@@ -100,6 +100,7 @@ r128CreateScreen( __DRIscreenPrivate *sPriv )
    R128DRIPtr r128DRIPriv = (R128DRIPtr)sPriv->pDevPriv;
    PFNGLXSCRENABLEEXTENSIONPROC glx_enable_extension =
      (PFNGLXSCRENABLEEXTENSIONPROC) (*dri_interface->getProcAddress("glxEnableExtension"));
+   int i;
 
    if (sPriv->devPrivSize != sizeof(R128DRIRec)) {
       fprintf(stderr,"\nERROR!  sizeof(R128DRIRec) does not match passed size from device driver\n");
@@ -225,15 +226,17 @@ r128CreateScreen( __DRIscreenPrivate *sPriv )
 
    r128Screen->driScreen = sPriv;
 
+   i = 0;
    if ( glx_enable_extension != NULL ) {
       if ( r128Screen->irq != 0 ) {
-	 (*glx_enable_extension)( sPriv->psc, "GLX_SGI_swap_control" );
+	  r128Screen->extensions[i++] = &driSwapControlExtension.base;
 	 (*glx_enable_extension)( sPriv->psc, "GLX_SGI_video_sync" );
-	 (*glx_enable_extension)( sPriv->psc, "GLX_MESA_swap_control" );
       }
 
       (*glx_enable_extension)( sPriv->psc, "GLX_MESA_swap_frame_usage" );
    }
+   r128Screen->extensions[i++] = NULL;
+   sPriv->extensions = r128Screen->extensions;
 
    return r128Screen;
 }
diff --git a/src/mesa/drivers/dri/r128/r128_screen.h b/src/mesa/drivers/dri/r128/r128_screen.h
index 8db8eea3587..97339272742 100644
--- a/src/mesa/drivers/dri/r128/r128_screen.h
+++ b/src/mesa/drivers/dri/r128/r128_screen.h
@@ -78,6 +78,8 @@ typedef struct {
    /* Configuration cache with default values for all contexts */
    driOptionCache optionCache;
 
+   const __DRIextension *extensions[2];
+
 } r128ScreenRec, *r128ScreenPtr;
 
 
diff --git a/src/mesa/drivers/dri/radeon/radeon_screen.c b/src/mesa/drivers/dri/radeon/radeon_screen.c
index 7e533fef2cc..46160babb01 100644
--- a/src/mesa/drivers/dri/radeon/radeon_screen.c
+++ b/src/mesa/drivers/dri/radeon/radeon_screen.c
@@ -332,11 +332,6 @@ radeonFillInModes( unsigned pixel_bits, unsigned depth_bits,
     return modes;
 }
 
-static const __DRIextension *radeonExtensions[] = {
-    &driCopySubBufferExtension.base,
-    NULL
-};
-
 /* Create the device specific screen private data struct.
  */
 static radeonScreenPtr
@@ -347,6 +342,7 @@ radeonCreateScreen( __DRIscreenPrivate *sPriv )
    unsigned char *RADEONMMIO;
    PFNGLXSCRENABLEEXTENSIONPROC glx_enable_extension =
      (PFNGLXSCRENABLEEXTENSIONPROC) (*dri_interface->getProcAddress("glxEnableExtension"));
+   int i;
 
    if (sPriv->devPrivSize != sizeof(RADEONDRIRec)) {
       fprintf(stderr,"\nERROR!  sizeof(RADEONDRIRec) does not match passed size from device driver\n");
@@ -735,13 +731,13 @@ radeonCreateScreen( __DRIscreenPrivate *sPriv )
 	 dri_priv->log2GARTTexGran;
    }
 
-   sPriv->extensions = radeonExtensions;
+   i = 0;
+   screen->extensions[i++] = &driCopySubBufferExtension.base;
 
    if ( glx_enable_extension != NULL ) {
       if ( screen->irq != 0 ) {
-	 (*glx_enable_extension)( sPriv->psc, "GLX_SGI_swap_control" );
+	  screen->extensions[i++] = &driSwapControlExtension.base;
 	 (*glx_enable_extension)( sPriv->psc, "GLX_SGI_video_sync" );
-	 (*glx_enable_extension)( sPriv->psc, "GLX_MESA_swap_control" );
       }
 
       (*glx_enable_extension)( sPriv->psc, "GLX_MESA_swap_frame_usage" );
@@ -750,6 +746,8 @@ radeonCreateScreen( __DRIscreenPrivate *sPriv )
 
       (*glx_enable_extension)( sPriv->psc, "GLX_SGI_make_current_read" );
    }
+   screen->extensions[i++] = NULL;
+   sPriv->extensions = screen->extensions;
 
 #if RADEON_COMMON && defined(RADEON_COMMON_FOR_R200)
    if (IS_R200_CLASS(screen)) {
diff --git a/src/mesa/drivers/dri/radeon/radeon_screen.h b/src/mesa/drivers/dri/radeon/radeon_screen.h
index 25e6fcf399a..eceab53f5f5 100644
--- a/src/mesa/drivers/dri/radeon/radeon_screen.h
+++ b/src/mesa/drivers/dri/radeon/radeon_screen.h
@@ -103,6 +103,8 @@ typedef struct {
 
    /* Configuration cache with default values for all contexts */
    driOptionCache optionCache;
+
+   const __DRIextension *extensions[3];
 } radeonScreenRec, *radeonScreenPtr;
 
 #define IS_R100_CLASS(screen) \
diff --git a/src/mesa/drivers/dri/unichrome/via_screen.c b/src/mesa/drivers/dri/unichrome/via_screen.c
index 53f4c5c5642..153e401a165 100644
--- a/src/mesa/drivers/dri/unichrome/via_screen.c
+++ b/src/mesa/drivers/dri/unichrome/via_screen.c
@@ -100,6 +100,7 @@ viaInitDriver(__DRIscreenPrivate *sPriv)
     VIADRIPtr gDRIPriv = (VIADRIPtr)sPriv->pDevPriv;
     PFNGLXSCRENABLEEXTENSIONPROC glx_enable_extension =
       (PFNGLXSCRENABLEEXTENSIONPROC) (*dri_interface->getProcAddress("glxEnableExtension"));
+    int i;
 
     if (sPriv->devPrivSize != sizeof(VIADRIRec)) {
       fprintf(stderr,"\nERROR!  sizeof(VIADRIRec) does not match passed size from device driver\n");
@@ -174,16 +175,18 @@ viaInitDriver(__DRIscreenPrivate *sPriv)
 
     viaScreen->sareaPrivOffset = gDRIPriv->sarea_priv_offset;
 
+    i = 0;
     if ( glx_enable_extension != NULL ) {
        if ( viaScreen->irqEnabled ) {
-	  (*glx_enable_extension)( sPriv->psc, "GLX_SGI_swap_control" );
+	  viaScreen->extensions[i++] = &driSwapControlExtension.base;
 	  (*glx_enable_extension)( sPriv->psc, "GLX_SGI_video_sync" );
-	  (*glx_enable_extension)( sPriv->psc, "GLX_MESA_swap_control" );
        }
 
        (*glx_enable_extension)( sPriv->psc, "GLX_SGI_make_current_read" );
        (*glx_enable_extension)( sPriv->psc, "GLX_MESA_swap_frame_usage" );
     }
+    viaScreen->extensions[i++] = NULL;
+    sPriv->extensions = viaScreen->extensions;
 
     return GL_TRUE;
 }
diff --git a/src/mesa/drivers/dri/unichrome/via_screen.h b/src/mesa/drivers/dri/unichrome/via_screen.h
index 84aa5aef88e..85f87c4da39 100644
--- a/src/mesa/drivers/dri/unichrome/via_screen.h
+++ b/src/mesa/drivers/dri/unichrome/via_screen.h
@@ -70,6 +70,8 @@ typedef struct {
 
     /* Configuration cache with default values for all contexts */
     driOptionCache optionCache;
+
+    const __DRIextension *extensions[2];
 } viaScreenPrivate;