gallium: Change pipe->flush() interface to optionally return a fence.

The cell driver still uses an internal CELL_FLUSH_WAIT flag, in the long run
proper fencing should be implemented for it.

28 files changed, 127 insertions, 83 deletions

diff --git a/src/gallium/auxiliary/util/u_gen_mipmap.c b/src/gallium/auxiliary/util/u_gen_mipmap.c
index e129c062be..ed12768e7f 100644
--- a/src/gallium/auxiliary/util/u_gen_mipmap.c
+++ b/src/gallium/auxiliary/util/u_gen_mipmap.c
@@ -935,7 +935,7 @@ util_gen_mipmap(struct gen_mipmap_state *ctx,
                               4,  /* verts */
                               2); /* attribs/vert */
 
-      pipe->flush(pipe, PIPE_FLUSH_WAIT);
+      pipe->flush(pipe, PIPE_FLUSH_RENDER_CACHE, NULL);
 
       /* need to signal that the texture has changed _after_ rendering to it */
       pipe->texture_update(pipe, pt, face, (1 << dstLevel));
diff --git a/src/gallium/drivers/cell/ppu/cell_flush.c b/src/gallium/drivers/cell/ppu/cell_flush.c
index 66a5627d84..3aaf3de668 100644
--- a/src/gallium/drivers/cell/ppu/cell_flush.c
+++ b/src/gallium/drivers/cell/ppu/cell_flush.c
@@ -35,12 +35,19 @@
 
 
 void
-cell_flush(struct pipe_context *pipe, unsigned flags)
+cell_flush(struct pipe_context *pipe, unsigned flags,
+           struct pipe_fence_handle **fence)
 {
    struct cell_context *cell = cell_context(pipe);
 
+   if (fence) {
+      *fence = NULL;
+      /* XXX: Implement real fencing */
+      flags |= CELL_FLUSH_WAIT;
+   }
+
    if (flags & PIPE_FLUSH_SWAPBUFFERS)
-      flags |= PIPE_FLUSH_WAIT;
+      flags |= CELL_FLUSH_WAIT;
 
    draw_flush( cell->draw );
    cell_flush_int(pipe, flags);
@@ -58,7 +65,7 @@ cell_flush_int(struct pipe_context *pipe, unsigned flags)
    ASSERT(!flushing);
    flushing = TRUE;
 
-   if (flags & PIPE_FLUSH_WAIT) {
+   if (flags & CELL_FLUSH_WAIT) {
       uint64_t *cmd = (uint64_t *) cell_batch_alloc(cell, sizeof(uint64_t));
       *cmd = CELL_CMD_FINISH;
    }
@@ -72,7 +79,7 @@ cell_flush_int(struct pipe_context *pipe, unsigned flags)
    }
 #endif
 
-   if (flags & PIPE_FLUSH_WAIT) {
+   if (flags & CELL_FLUSH_WAIT) {
       /* Wait for ack */
       for (i = 0; i < cell->num_spus; i++) {
          uint k = wait_mbox_message(cell_global.spe_contexts[i]);
diff --git a/src/gallium/drivers/cell/ppu/cell_flush.h b/src/gallium/drivers/cell/ppu/cell_flush.h
index 7f940ae76b..8f0645c429 100644
--- a/src/gallium/drivers/cell/ppu/cell_flush.h
+++ b/src/gallium/drivers/cell/ppu/cell_flush.h
@@ -29,8 +29,11 @@
 #ifndef CELL_FLUSH
 #define CELL_FLUSH
 
+#define CELL_FLUSH_WAIT 0x80000000
+
 extern void
-cell_flush(struct pipe_context *pipe, unsigned flags);
+cell_flush(struct pipe_context *pipe, unsigned flags,
+           struct pipe_fence_handle **fence);
 
 extern void
 cell_flush_int(struct pipe_context *pipe, unsigned flags);
diff --git a/src/gallium/drivers/cell/ppu/cell_vbuf.c b/src/gallium/drivers/cell/ppu/cell_vbuf.c
index cc727ff4ed..3a181b585c 100644
--- a/src/gallium/drivers/cell/ppu/cell_vbuf.c
+++ b/src/gallium/drivers/cell/ppu/cell_vbuf.c
@@ -243,7 +243,7 @@ cell_vbuf_draw(struct vbuf_render *vbr,
 
 #if 0
    /* helpful for debug */
-   cell_flush_int(&cell->pipe, PIPE_FLUSH_WAIT);
+   cell_flush_int(&cell->pipe, CELL_FLUSH_WAIT);
 #endif
 }
 
diff --git a/src/gallium/drivers/cell/ppu/cell_vertex_shader.c b/src/gallium/drivers/cell/ppu/cell_vertex_shader.c
index f5c27852c1..b418857ccd 100644
--- a/src/gallium/drivers/cell/ppu/cell_vertex_shader.c
+++ b/src/gallium/drivers/cell/ppu/cell_vertex_shader.c
@@ -133,7 +133,7 @@ cell_vertex_shader_queue_flush(struct draw_context *draw)
       vs->num_elts = n;
       send_mbox_message(cell_global.spe_contexts[0], CELL_CMD_VS_EXECUTE);
 
-      cell_flush_int(& cell->pipe, PIPE_FLUSH_WAIT);
+      cell_flush_int(& cell->pipe, CELL_FLUSH_WAIT);
    }
 
    draw->vs.post_nr = draw->vs.queue_nr;
diff --git a/src/gallium/drivers/failover/fo_context.c b/src/gallium/drivers/failover/fo_context.c
index afc0d7eb1e..cb95ba516f 100644
--- a/src/gallium/drivers/failover/fo_context.c
+++ b/src/gallium/drivers/failover/fo_context.c
@@ -69,7 +69,7 @@ static boolean failover_draw_elements( struct pipe_context *pipe,
 					start, 
 					count )) {
 
-	 failover->hw->flush( failover->hw, ~0 );
+	 failover->hw->flush( failover->hw, ~0, NULL );
 	 failover->mode = FO_SW;
       }
    }
@@ -92,7 +92,7 @@ static boolean failover_draw_elements( struct pipe_context *pipe,
        * intervening flush.  Unlikely to be much performance impact to
        * this:
        */
-      failover->sw->flush( failover->sw, ~0 );
+      failover->sw->flush( failover->sw, ~0, NULL );
    }
 
    return TRUE;
diff --git a/src/gallium/drivers/i915simple/i915_batch.h b/src/gallium/drivers/i915simple/i915_batch.h
index fb88cd6db0..4ea06ce02b 100644
--- a/src/gallium/drivers/i915simple/i915_batch.h
+++ b/src/gallium/drivers/i915simple/i915_batch.h
@@ -44,9 +44,9 @@
 
 #define ADVANCE_BATCH()
 
-#define FLUSH_BATCH() do { 				\
+#define FLUSH_BATCH(fence) do { 			\
    if (0) i915_dump_batchbuffer( i915 );		\
-   i915->winsys->batch_flush( i915->winsys );		\
+   i915->winsys->batch_flush( i915->winsys, fence );	\
    i915->batch_start = NULL;				\
    i915->hardware_dirty = ~0;				\
 } while (0)
diff --git a/src/gallium/drivers/i915simple/i915_blit.c b/src/gallium/drivers/i915simple/i915_blit.c
index db4671ff55..24449e3fb3 100644
--- a/src/gallium/drivers/i915simple/i915_blit.c
+++ b/src/gallium/drivers/i915simple/i915_blit.c
@@ -70,7 +70,7 @@ i915_fill_blit(struct i915_context *i915,
 
 
    if (!BEGIN_BATCH(6, 1)) {
-      FLUSH_BATCH();
+      FLUSH_BATCH(NULL);
       assert(BEGIN_BATCH(6, 1));
    }
    OUT_BATCH(CMD);
@@ -145,7 +145,7 @@ i915_copy_blit( struct i915_context *i915,
 
 
    if (!BEGIN_BATCH(8, 2)) {
-      FLUSH_BATCH();
+      FLUSH_BATCH(NULL);
       assert(BEGIN_BATCH(8, 2));
    }
    OUT_BATCH(CMD);
diff --git a/src/gallium/drivers/i915simple/i915_flush.c b/src/gallium/drivers/i915simple/i915_flush.c
index 96a54281f1..7d23e6b6b9 100644
--- a/src/gallium/drivers/i915simple/i915_flush.c
+++ b/src/gallium/drivers/i915simple/i915_flush.c
@@ -37,11 +37,9 @@
 #include "i915_batch.h"
 
 
-/**
- * In future we may want a fence-like interface instead of finish.
- */
 static void i915_flush( struct pipe_context *pipe,
-			unsigned flags )
+                        unsigned flags,
+                        struct pipe_fence_handle **fence )
 {
    struct i915_context *i915 = i915_context(pipe);
 
@@ -60,7 +58,7 @@ static void i915_flush( struct pipe_context *pipe,
 	 flush |= FLUSH_MAP_CACHE;
 
       if (!BEGIN_BATCH(1, 0)) {
-	 FLUSH_BATCH();
+	 FLUSH_BATCH(NULL);
 	 assert(BEGIN_BATCH(1, 0));
       }
       OUT_BATCH( flush );
@@ -69,11 +67,7 @@ static void i915_flush( struct pipe_context *pipe,
 
    /* If there are no flags, just flush pending commands to hardware:
     */
-   FLUSH_BATCH();
-
-   if (flags & PIPE_FLUSH_WAIT) {
-      i915->winsys->batch_finish(i915->winsys);
-   }
+   FLUSH_BATCH(fence);
 }
 
 
diff --git a/src/gallium/drivers/i915simple/i915_prim_emit.c b/src/gallium/drivers/i915simple/i915_prim_emit.c
index d8de5178f6..b6fb0a6d88 100644
--- a/src/gallium/drivers/i915simple/i915_prim_emit.c
+++ b/src/gallium/drivers/i915simple/i915_prim_emit.c
@@ -140,7 +140,7 @@ emit_prim( struct draw_stage *stage,
    assert(vertex_size >= 12); /* never smaller than 12 bytes */
 
    if (!BEGIN_BATCH( 1 + nr * vertex_size / 4, 0 )) {
-      FLUSH_BATCH();
+      FLUSH_BATCH(NULL);
 
       /* Make sure state is re-emitted after a flush: 
        */
diff --git a/src/gallium/drivers/i915simple/i915_prim_vbuf.c b/src/gallium/drivers/i915simple/i915_prim_vbuf.c
index eb64f51943..7fb2adbb53 100644
--- a/src/gallium/drivers/i915simple/i915_prim_vbuf.c
+++ b/src/gallium/drivers/i915simple/i915_prim_vbuf.c
@@ -161,7 +161,7 @@ i915_vbuf_render_draw( struct vbuf_render *render,
       i915_emit_hardware_state( i915 );
 
    if (!BEGIN_BATCH( 1 + (nr_indices + 1)/2, 1 )) {
-      FLUSH_BATCH();
+      FLUSH_BATCH(NULL);
 
       /* Make sure state is re-emitted after a flush: 
        */
diff --git a/src/gallium/drivers/i915simple/i915_state_emit.c b/src/gallium/drivers/i915simple/i915_state_emit.c
index a7498d22b7..6f947d4346 100644
--- a/src/gallium/drivers/i915simple/i915_state_emit.c
+++ b/src/gallium/drivers/i915simple/i915_state_emit.c
@@ -115,7 +115,7 @@ i915_emit_hardware_state(struct i915_context *i915 )
 #endif
    
    if(!BEGIN_BATCH(dwords, relocs)) {
-      FLUSH_BATCH();
+      FLUSH_BATCH(NULL);
       assert(BEGIN_BATCH(dwords, relocs));
    }
 
diff --git a/src/gallium/drivers/i915simple/i915_winsys.h b/src/gallium/drivers/i915simple/i915_winsys.h
index aea3003281..5e16543f4e 100644
--- a/src/gallium/drivers/i915simple/i915_winsys.h
+++ b/src/gallium/drivers/i915simple/i915_winsys.h
@@ -56,6 +56,7 @@ extern "C" {
  */
 
 struct pipe_buffer;
+struct pipe_fence_handle;
 struct pipe_winsys;
 struct pipe_screen;
 
@@ -103,8 +104,8 @@ struct i915_winsys {
 			unsigned access_flags,
 			unsigned delta );
    
-   void (*batch_flush)( struct i915_winsys *sws );
-   void (*batch_finish)( struct i915_winsys *sws );
+   void (*batch_flush)( struct i915_winsys *sws,
+                        struct pipe_fence_handle **fence );
 };
 
 #define I915_BUFFER_ACCESS_WRITE   0x1 
diff --git a/src/gallium/drivers/i965simple/brw_flush.c b/src/gallium/drivers/i965simple/brw_flush.c
index 5216c680cf..e6001c30d9 100644
--- a/src/gallium/drivers/i965simple/brw_flush.c
+++ b/src/gallium/drivers/i965simple/brw_flush.c
@@ -36,14 +36,11 @@
 #include "brw_batch.h"
 
 
-/**
- * In future we may want a fence-like interface instead of finish.
- */
 static void brw_flush( struct pipe_context *pipe,
-			unsigned flags )
+                       unsigned flags,
+                       struct pipe_fence_handle **fence )
 {
    struct brw_context *brw = brw_context(pipe);
-   struct pipe_fence_handle *fence;
 
    /* Do we need to emit an MI_FLUSH command to flush the hardware
     * caches?
@@ -65,11 +62,7 @@ static void brw_flush( struct pipe_context *pipe,
 
    /* If there are no flags, just flush pending commands to hardware:
     */
-   FLUSH_BATCH( &fence );
-
-   if (flags & PIPE_FLUSH_WAIT) {
-//      brw->winsys->wait_fence(brw->winsys, fence);
-   }
+   FLUSH_BATCH( fence );
 }
 
 
diff --git a/src/gallium/drivers/softpipe/sp_flush.c b/src/gallium/drivers/softpipe/sp_flush.c
index 2cbd0d7cab..0625b69099 100644
--- a/src/gallium/drivers/softpipe/sp_flush.c
+++ b/src/gallium/drivers/softpipe/sp_flush.c
@@ -40,13 +40,10 @@
 #include "sp_winsys.h"
 
 
-/* There will be actual work to do here.  In future we may want a
- * fence-like interface instead of finish, and perhaps flush will take
- * flags to indicate what type of flush is required.
- */
 void
 softpipe_flush( struct pipe_context *pipe,
-		unsigned flags )
+		unsigned flags,
+                struct pipe_fence_handle **fence )
 {
    struct softpipe_context *softpipe = softpipe_context(pipe);
    uint i;
@@ -72,5 +69,8 @@ softpipe_flush( struct pipe_context *pipe,
     * to unmap surfaces when flushing.
     */
    softpipe_unmap_surfaces(softpipe);
+
+   if (fence)
+      *fence = NULL;
 }
 
diff --git a/src/gallium/drivers/softpipe/sp_flush.h b/src/gallium/drivers/softpipe/sp_flush.h
index 34ec617866..68d9b5fa83 100644
--- a/src/gallium/drivers/softpipe/sp_flush.h
+++ b/src/gallium/drivers/softpipe/sp_flush.h
@@ -29,7 +29,9 @@
 #define SP_FLUSH_H
 
 struct pipe_context;
+struct pipe_fence_handle;
 
-void softpipe_flush(struct pipe_context *pipe, unsigned flags );
+void softpipe_flush(struct pipe_context *pipe, unsigned flags,
+                    struct pipe_fence_handle **fence);
 
 #endif
diff --git a/src/gallium/include/pipe/p_context.h b/src/gallium/include/pipe/p_context.h
index a3824601be..b2e49bef4c 100644
--- a/src/gallium/include/pipe/p_context.h
+++ b/src/gallium/include/pipe/p_context.h
@@ -37,7 +37,7 @@ extern "C" {
 
    
 struct pipe_screen;
-
+struct pipe_fence_handle;
 struct pipe_state_cache;
 
 /* Opaque driver handles:
@@ -202,7 +202,8 @@ struct pipe_context {
    /* Flush rendering:
     */
    void (*flush)( struct pipe_context *pipe,
-		  unsigned flags );
+                  unsigned flags,
+                  struct pipe_fence_handle **fence );
 };
 
 
diff --git a/src/gallium/include/pipe/p_defines.h b/src/gallium/include/pipe/p_defines.h
index bc938ba253..586951d956 100644
--- a/src/gallium/include/pipe/p_defines.h
+++ b/src/gallium/include/pipe/p_defines.h
@@ -201,8 +201,7 @@ enum pipe_texture_target {
  */
 #define PIPE_FLUSH_RENDER_CACHE   0x1
 #define PIPE_FLUSH_TEXTURE_CACHE  0x2
-#define PIPE_FLUSH_WAIT           0x4
-#define PIPE_FLUSH_SWAPBUFFERS    0x8 
+#define PIPE_FLUSH_SWAPBUFFERS    0x4
 
 
 /**
diff --git a/src/gallium/winsys/dri/intel/intel_context.c b/src/gallium/winsys/dri/intel/intel_context.c
index 79b320c6bf..8eba33c313 100644
--- a/src/gallium/winsys/dri/intel/intel_context.c
+++ b/src/gallium/winsys/dri/intel/intel_context.c
@@ -228,7 +228,7 @@ intelDestroyContext(__DRIcontextPrivate * driContextPriv)
 
    assert(intel);               /* should never be null */
    if (intel) {
-      st_flush(intel->st, PIPE_FLUSH_WAIT);
+      st_finish(intel->st);
 
       intel_batchbuffer_free(intel->batch);
 
@@ -256,7 +256,7 @@ GLboolean
 intelUnbindContext(__DRIcontextPrivate * driContextPriv)
 {
    struct intel_context *intel = intel_context(driContextPriv);
-   st_flush(intel->st, 0x0);
+   st_flush(intel->st, PIPE_FLUSH_RENDER_CACHE, NULL);
    /* XXX make_current(NULL)? */
    return GL_TRUE;
 }
diff --git a/src/gallium/winsys/dri/intel/intel_winsys_i915.c b/src/gallium/winsys/dri/intel/intel_winsys_i915.c
index 2def1afc31..4d183db7c3 100644
--- a/src/gallium/winsys/dri/intel/intel_winsys_i915.c
+++ b/src/gallium/winsys/dri/intel/intel_winsys_i915.c
@@ -39,12 +39,14 @@
 #include "intel_winsys.h"
 
 #include "pipe/p_util.h"
+#include "pipe/p_winsys.h"
 #include "i915simple/i915_winsys.h"
 #include "i915simple/i915_screen.h"
 
 
 struct intel_i915_winsys {
    struct i915_winsys winsys;   /**< batch buffer funcs */
+   struct pipe_winsys *pws;
    struct intel_context *intel;
 };
 
@@ -112,19 +114,22 @@ static void intel_i915_batch_reloc( struct i915_winsys *sws,
 
 
 
-static void intel_i915_batch_flush( struct i915_winsys *sws )
+static void intel_i915_batch_flush( struct i915_winsys *sws,
+                                    struct pipe_fence_handle **fence )
 {
-   struct intel_context *intel = intel_i915_winsys(sws)->intel;
+   struct intel_i915_winsys *iws = intel_i915_winsys(sws);
+   struct intel_context *intel = iws->intel;
+   union {
+      struct _DriFenceObject *dri;
+      struct pipe_fence_handle *pipe;
+   } fu;
 
-   intel_batchbuffer_flush( intel->batch );
-//   if (0) intel_i915_batch_wait_idle( sws );
-}
+   fu.dri = intel_batchbuffer_flush( intel->batch );
 
+   if (fu.dri)
+      iws->pws->fence_reference(iws->pws, fence, fu.pipe);
 
-static void intel_i915_batch_finish( struct i915_winsys *sws )
-{
-   struct intel_context *intel = intel_i915_winsys(sws)->intel;
-   intel_batchbuffer_finish( intel->batch );
+//   if (0) intel_i915_batch_wait_idle( sws );
 }
 
 
@@ -145,7 +150,7 @@ intel_create_i915simple( struct intel_context *intel,
    iws->winsys.batch_dword = intel_i915_batch_dword;
    iws->winsys.batch_reloc = intel_i915_batch_reloc;
    iws->winsys.batch_flush = intel_i915_batch_flush;
-   iws->winsys.batch_finish = intel_i915_batch_finish;
+   iws->pws = winsys;
    iws->intel = intel;
 
    screen = i915_create_screen(winsys, intel->intelScreen->deviceID);
diff --git a/src/gallium/winsys/xlib/xm_winsys.c b/src/gallium/winsys/xlib/xm_winsys.c
index 7baaae295c..c930a1d196 100644
--- a/src/gallium/winsys/xlib/xm_winsys.c
+++ b/src/gallium/winsys/xlib/xm_winsys.c
@@ -570,6 +570,33 @@ xm_surface_release(struct pipe_winsys *winsys, struct pipe_surface **s)
 }
 
 
+/*
+ * Fence functions - basically nothing to do, as we don't create any actual
+ * fence objects.
+ */
+
+static void
+xm_fence_reference(struct pipe_winsys *sws, struct pipe_fence_handle **ptr,
+                   struct pipe_fence_handle *fence)
+{
+}
+
+
+static int
+xm_fence_signalled(struct pipe_winsys *sws, struct pipe_fence_handle *fence,
+                   unsigned flag)
+{
+   return 0;
+}
+
+
+static int
+xm_fence_finish(struct pipe_winsys *sws, struct pipe_fence_handle *fence,
+                unsigned flag)
+{
+   return 0;
+}
+
 
 /**
  * Return pointer to a pipe_winsys object.
@@ -603,6 +630,10 @@ xmesa_get_pipe_winsys_aub(struct xmesa_visual *xm_vis)
       ws->base.surface_alloc_storage = xm_surface_alloc_storage;
       ws->base.surface_release = xm_surface_release;
 
+      ws->fence_reference = xm_fence_reference;
+      ws->fence_signalled = xm_fence_signalled;
+      ws->fence_finish = xm_fence_finish;
+
       ws->base.flush_frontbuffer = xm_flush_frontbuffer;
       ws->base.printf = xm_printf;
       ws->base.get_name = xm_get_name;
diff --git a/src/mesa/state_tracker/st_cb_accum.c b/src/mesa/state_tracker/st_cb_accum.c
index f1fddc4e02..a623d0bcc0 100644
--- a/src/mesa/state_tracker/st_cb_accum.c
+++ b/src/mesa/state_tracker/st_cb_accum.c
@@ -214,7 +214,7 @@ st_Accum(GLcontext *ctx, GLenum op, GLfloat value)
    const GLint height = ctx->DrawBuffer->_Ymax - ypos;
 
    /* make sure color bufs aren't cached */
-   pipe->flush(pipe, PIPE_FLUSH_RENDER_CACHE);
+   pipe->flush(pipe, PIPE_FLUSH_RENDER_CACHE, NULL);
 
    switch (op) {
    case GL_ADD:
diff --git a/src/mesa/state_tracker/st_cb_drawpixels.c b/src/mesa/state_tracker/st_cb_drawpixels.c
index 026f015fd8..43cc21d1fb 100644
--- a/src/mesa/state_tracker/st_cb_drawpixels.c
+++ b/src/mesa/state_tracker/st_cb_drawpixels.c
@@ -737,7 +737,7 @@ draw_stencil_pixels(GLcontext *ctx, GLint x, GLint y,
    GLint skipPixels;
    ubyte *stmap;
 
-   pipe->flush(pipe, PIPE_FLUSH_RENDER_CACHE);
+   pipe->flush(pipe, PIPE_FLUSH_RENDER_CACHE, NULL);
 
    /* map the stencil buffer */
    stmap = pipe_surface_map(ps);
@@ -952,7 +952,7 @@ st_CopyPixels(GLcontext *ctx, GLint srcx, GLint srcy,
    enum pipe_format srcFormat, texFormat;
 
    /* make sure rendering has completed */
-   pipe->flush(pipe, PIPE_FLUSH_RENDER_CACHE);
+   pipe->flush(pipe, PIPE_FLUSH_RENDER_CACHE, NULL);
 
    st_validate_state(st);
 
diff --git a/src/mesa/state_tracker/st_cb_fbo.c b/src/mesa/state_tracker/st_cb_fbo.c
index 5384252a8e..ec7788923a 100644
--- a/src/mesa/state_tracker/st_cb_fbo.c
+++ b/src/mesa/state_tracker/st_cb_fbo.c
@@ -366,7 +366,7 @@ st_finish_render_texture(GLcontext *ctx,
 
    assert(strb);
 
-   ctx->st->pipe->flush(ctx->st->pipe, PIPE_FLUSH_RENDER_CACHE);
+   ctx->st->pipe->flush(ctx->st->pipe, PIPE_FLUSH_RENDER_CACHE, NULL);
 
    /*
    printf("FINISH RENDER TO TEXTURE surf=%p\n", strb->surface);
diff --git a/src/mesa/state_tracker/st_cb_flush.c b/src/mesa/state_tracker/st_cb_flush.c
index dbec993f1b..a536a059bd 100644
--- a/src/mesa/state_tracker/st_cb_flush.c
+++ b/src/mesa/state_tracker/st_cb_flush.c
@@ -43,19 +43,21 @@
 #include "pipe/p_winsys.h"
 
 
-void st_flush( struct st_context *st, uint pipeFlushFlags )
+void st_flush( struct st_context *st, uint pipeFlushFlags,
+               struct pipe_fence_handle **fence )
 {
    FLUSH_VERTICES(st->ctx, 0);
 
-   st->pipe->flush( st->pipe, pipeFlushFlags );
+   st->pipe->flush( st->pipe, pipeFlushFlags, fence );
 }
 
 
-static void st_gl_flush( struct st_context *st, uint pipeFlushFlags )
+static void st_gl_flush( struct st_context *st, uint pipeFlushFlags,
+                         struct pipe_fence_handle **fence )
 {
    GLframebuffer *fb = st->ctx->DrawBuffer;
 
-   FLUSH_VERTICES(st->ctx, 0);
+   st_flush( st, pipeFlushFlags, fence );
 
    if (!fb)
       return;
@@ -80,15 +82,6 @@ static void st_gl_flush( struct st_context *st, uint pipeFlushFlags )
          = st_renderbuffer(fb->Attachment[BUFFER_FRONT_LEFT].Renderbuffer);
       struct pipe_surface *front_surf = strb->surface;
 
-      /* If we aren't rendering to the frontbuffer, this is a noop.
-       * This should be uncontroversial for glFlush, though people may
-       * feel more strongly about glFinish.
-       *
-       * Additionally, need to make sure that the frontbuffer_dirty
-       * flag really gets set on frontbuffer rendering.
-       */
-      st->pipe->flush( st->pipe, pipeFlushFlags );
-
       /* Hook for copying "fake" frontbuffer if necessary:
        */
       st->pipe->winsys->flush_frontbuffer( st->pipe->winsys, front_surf,
@@ -103,7 +96,18 @@ static void st_gl_flush( struct st_context *st, uint pipeFlushFlags )
  */
 static void st_glFlush(GLcontext *ctx)
 {
-   st_gl_flush(ctx->st, PIPE_FLUSH_RENDER_CACHE);
+   st_gl_flush(ctx->st, PIPE_FLUSH_RENDER_CACHE, NULL);
+}
+
+
+void st_finish( struct st_context *st )
+{
+   struct pipe_fence_handle *fence;
+
+   st_gl_flush(st, PIPE_FLUSH_RENDER_CACHE, &fence);
+
+   st->pipe->winsys->fence_finish(st->pipe->winsys, fence, 0);
+   st->pipe->winsys->fence_reference(st->pipe->winsys, &fence, NULL);
 }
 
 
@@ -112,7 +116,7 @@ static void st_glFlush(GLcontext *ctx)
  */
 static void st_glFinish(GLcontext *ctx)
 {
-   st_gl_flush(ctx->st, PIPE_FLUSH_RENDER_CACHE | PIPE_FLUSH_WAIT);
+   st_finish( ctx->st );
 }
 
 
diff --git a/src/mesa/state_tracker/st_cb_readpixels.c b/src/mesa/state_tracker/st_cb_readpixels.c
index 4cf9adcd28..e9fcdf69a1 100644
--- a/src/mesa/state_tracker/st_cb_readpixels.c
+++ b/src/mesa/state_tracker/st_cb_readpixels.c
@@ -160,7 +160,7 @@ st_readpixels(GLcontext *ctx, GLint x, GLint y, GLsizei width, GLsizei height,
       return;
 
    /* make sure rendering has completed */
-   pipe->flush(pipe, PIPE_FLUSH_RENDER_CACHE);
+   pipe->flush(pipe, PIPE_FLUSH_RENDER_CACHE, NULL);
 
    if (format == GL_STENCIL_INDEX) {
       st_read_stencil_pixels(ctx, x, y, width, height, type, pack, dest);
diff --git a/src/mesa/state_tracker/st_framebuffer.c b/src/mesa/state_tracker/st_framebuffer.c
index d46a9178b1..075e9d1bd6 100644
--- a/src/mesa/state_tracker/st_framebuffer.c
+++ b/src/mesa/state_tracker/st_framebuffer.c
@@ -186,7 +186,8 @@ st_notify_swapbuffers(struct st_framebuffer *stfb)
 
    if (ctx && ctx->DrawBuffer == &stfb->Base) {
       st_flush( ctx->st, 
-		PIPE_FLUSH_RENDER_CACHE | PIPE_FLUSH_SWAPBUFFERS);
+		PIPE_FLUSH_RENDER_CACHE | PIPE_FLUSH_SWAPBUFFERS,
+                NULL );
    }
 }
 
diff --git a/src/mesa/state_tracker/st_public.h b/src/mesa/state_tracker/st_public.h
index 3c397b126a..9d88ce9764 100644
--- a/src/mesa/state_tracker/st_public.h
+++ b/src/mesa/state_tracker/st_public.h
@@ -45,6 +45,7 @@
 struct st_context;
 struct st_framebuffer;
 struct pipe_context;
+struct pipe_fence_handle;
 struct pipe_surface;
 
 
@@ -78,7 +79,9 @@ void st_make_current(struct st_context *st,
                      struct st_framebuffer *draw,
                      struct st_framebuffer *read);
 
-void st_flush( struct st_context *st, uint pipeFlushFlags );
+void st_flush( struct st_context *st, uint pipeFlushFlags,
+               struct pipe_fence_handle **fence );
+void st_finish( struct st_context *st );
 
 void st_notify_swapbuffers(struct st_framebuffer *stfb);
 void st_notify_swapbuffers_complete(struct st_framebuffer *stfb);