i965g: add lots of error checks and early returns

Any allocation that may fail should be checked, and propogate the
error upwards.  At the highest level we will flush batch and retry.

This is an alternate strategy to what the original DRI driver did of
attempting to flush batch from the lowest levels (eg inside
BEGIN_BATCH).  The trouble with that strategy was that flushes could
occur at unexpected times, and additionally there was a need for a
wierd notification mechanism to propogate the 'lost context' state
back up to higher levels.

Propogating the errors directly gives us a lot of flexibility how to
deal with these states, at the expense of a lot more checking in the
code.

Will add some sanity checks later to make sure that out-of-memory
conditions are properly escalated and not lost halfway up the stack.

1 files changed, 127 insertions, 99 deletions

diff --git a/src/gallium/drivers/i965/brw_wm_surface_state.c b/src/gallium/drivers/i965/brw_wm_surface_state.c
index b055dde20c..e5d0329967 100644
--- a/src/gallium/drivers/i965/brw_wm_surface_state.c
+++ b/src/gallium/drivers/i965/brw_wm_surface_state.c
@@ -40,31 +40,40 @@
 
 
 
-static void
+static enum pipe_error
 brw_update_texture_surface( struct brw_context *brw,
 			    struct brw_texture *tex,
-			    GLuint surf )
+                            struct brw_winsys_buffer **bo_out)
 {
-   brw->wm.surf_bo[surf] = brw_search_cache(&brw->surface_cache,
-                                            BRW_SS_SURFACE,
-                                            &tex->ss, sizeof tex->ss,
-                                            &tex->bo, 1,
-                                            NULL);
-
-   if (brw->wm.surf_bo[surf] == NULL) {
-      brw->wm.surf_bo[surf] = brw_upload_cache(&brw->surface_cache, BRW_SS_SURFACE,
-					       &tex->ss, sizeof tex->ss,
-					       &tex->bo, 1,
-					       &tex->ss, sizeof tex->ss,
-					       NULL, NULL);
+   enum pipe_error ret;
+
+   if (brw_search_cache(&brw->surface_cache,
+                        BRW_SS_SURFACE,
+                        &tex->ss, sizeof tex->ss,
+                        &tex->bo, 1,
+                        NULL,
+                        bo_out))
+      return PIPE_OK;
+
+   ret = brw_upload_cache(&brw->surface_cache, BRW_SS_SURFACE,
+                          &tex->ss, sizeof tex->ss,
+                          &tex->bo, 1,
+                          &tex->ss, sizeof tex->ss,
+                          NULL, NULL,
+                          bo_out);
+   if (ret)
+      return ret;
       
-      /* Emit relocation to surface contents */
-      brw->sws->bo_emit_reloc(brw->wm.surf_bo[surf],
-			      BRW_USAGE_SAMPLER,
-			      0,
-			      offsetof(struct brw_surface_state, ss1),
-			      tex->bo);
-   }
+   /* Emit relocation to surface contents */
+   ret = brw->sws->bo_emit_reloc(*bo_out,
+                                 BRW_USAGE_SAMPLER,
+                                 0,
+                                 offsetof(struct brw_surface_state, ss1),
+                                 tex->bo);
+   if (ret)
+      return ret;
+
+   return PIPE_OK;
 }
 
 
@@ -79,13 +88,14 @@ brw_update_texture_surface( struct brw_context *brw,
  * While it is only used for the front/back buffer currently, it should be
  * usable for further buffers when doing ARB_draw_buffer support.
  */
-static void
-brw_update_renderbuffer_surface(struct brw_context *brw,
-				struct brw_surface *surface,
-				unsigned int unit)
+static enum pipe_error
+brw_update_render_surface(struct brw_context *brw,
+                          struct brw_surface *surface,
+                          struct brw_winsys_buffer **bo_out)
 {
    struct brw_surf_ss0 blend_ss0 = brw->curr.blend->ss0;
    struct brw_surface_state ss;
+   enum pipe_error ret;
 
    /* Surfaces are potentially shared between contexts, so can't
     * scribble the in-place ss0 value in the surface.
@@ -98,30 +108,35 @@ brw_update_renderbuffer_surface(struct brw_context *brw,
    ss.ss0.writedisable_red   = blend_ss0.writedisable_red;
    ss.ss0.writedisable_alpha = blend_ss0.writedisable_alpha;
 
-   brw->sws->bo_unreference(brw->wm.surf_bo[unit]);
-   brw->wm.surf_bo[unit] = brw_search_cache(&brw->surface_cache,
-					    BRW_SS_SURFACE,
-					    &ss, sizeof(ss),
-					    &surface->bo, 1,
-					    NULL);
-
-   if (brw->wm.surf_bo[unit] == NULL) {
-
-      brw->wm.surf_bo[unit] = brw_upload_cache(&brw->surface_cache,
-                                               BRW_SS_SURFACE,
-                                               &ss, sizeof ss,
-					       &surface->bo, 1,
-					       &ss, sizeof ss,
-					       NULL, NULL);
+   if (brw_search_cache(&brw->surface_cache,
+                        BRW_SS_SURFACE,
+                        &ss, sizeof(ss),
+                        &surface->bo, 1,
+                        NULL,
+                        bo_out))
+      return PIPE_OK;
+       
+   ret = brw_upload_cache(&brw->surface_cache,
+                          BRW_SS_SURFACE,
+                          &ss, sizeof ss,
+                          &surface->bo, 1,
+                          &ss, sizeof ss,
+                          NULL, NULL,
+                          bo_out);
+   if (ret)
+      return ret;
 
       /* XXX: we will only be rendering to this surface:
        */
-      brw->sws->bo_emit_reloc(brw->wm.surf_bo[unit],
-			      BRW_USAGE_RENDER_TARGET,
-			      ss.ss1.base_addr - surface->bo->offset[0], /* XXX */
-			      offsetof(struct brw_surface_state, ss1),
-			      surface->bo);
-   }
+   ret = brw->sws->bo_emit_reloc(*bo_out,
+                                 BRW_USAGE_RENDER_TARGET,
+                                 ss.ss1.base_addr - surface->bo->offset[0], /* XXX */
+                                 offsetof(struct brw_surface_state, ss1),
+                                 surface->bo);
+   if (ret)
+      return ret;
+
+   return PIPE_OK;
 }
 
 
@@ -129,60 +144,60 @@ brw_update_renderbuffer_surface(struct brw_context *brw,
  * Constructs the binding table for the WM surface state, which maps unit
  * numbers to surface state objects.
  */
-static struct brw_winsys_buffer *
-brw_wm_get_binding_table(struct brw_context *brw)
+static enum pipe_error
+brw_wm_get_binding_table(struct brw_context *brw,
+                         struct brw_winsys_buffer **bo_out )
 {
-   struct brw_winsys_buffer *bind_bo;
+   enum pipe_error ret;
+   uint32_t data[BRW_WM_MAX_SURF];
+   GLuint data_size = brw->wm.nr_surfaces * sizeof data[0];
+   int i;
 
    assert(brw->wm.nr_surfaces <= BRW_WM_MAX_SURF);
+   assert(brw->wm.nr_surfaces > 0);
 
    /* Note there is no key for this search beyond the values in the
     * relocation array:
     */
-   bind_bo = brw_search_cache(&brw->surface_cache, BRW_SS_SURF_BIND,
-			      NULL, 0,
-			      brw->wm.surf_bo, brw->wm.nr_surfaces,
-			      NULL);
-
-   if (bind_bo == NULL) {
-      uint32_t data[BRW_WM_MAX_SURF];
-      GLuint data_size = brw->wm.nr_surfaces * sizeof data[0];
-      int i;
-
-      for (i = 0; i < brw->wm.nr_surfaces; i++)
-	 data[i] = brw->wm.surf_bo[i]->offset[0];
-
-      bind_bo = brw_upload_cache( &brw->surface_cache, BRW_SS_SURF_BIND,
-				  NULL, 0,
-				  brw->wm.surf_bo, brw->wm.nr_surfaces,
-				  data, data_size,
-				  NULL, NULL);
-
-      /* Emit binding table relocations to surface state */
-      for (i = 0; i < brw->wm.nr_surfaces; i++) {
-	 brw->sws->bo_emit_reloc(bind_bo,
-				 BRW_USAGE_STATE,
-				 0,
-				 i * sizeof(GLuint),
-				 brw->wm.surf_bo[i]);
-      }
+   if (brw_search_cache(&brw->surface_cache, BRW_SS_SURF_BIND,
+                        NULL, 0,
+                        brw->wm.surf_bo,
+                        brw->wm.nr_surfaces,
+                        NULL,
+                        bo_out))
+      return PIPE_OK;
+
+   for (i = 0; i < brw->wm.nr_surfaces; i++)
+      data[i] = brw->wm.surf_bo[i]->offset[0];
+
+   ret = brw_upload_cache( &brw->surface_cache, BRW_SS_SURF_BIND,
+                           NULL, 0,
+                           brw->wm.surf_bo, brw->wm.nr_surfaces,
+                           data, data_size,
+                           NULL, NULL,
+                           bo_out);
+   if (ret)
+      return ret;
+
+   /* Emit binding table relocations to surface state */
+   for (i = 0; i < brw->wm.nr_surfaces; i++) {
+      ret = brw->sws->bo_emit_reloc(*bo_out,
+                                    BRW_USAGE_STATE,
+                                    0,
+                                    i * sizeof(GLuint),
+                                    brw->wm.surf_bo[i]);
+      if (ret)
+         return ret;
    }
 
-   return bind_bo;
+   return PIPE_OK;
 }
 
-static int prepare_wm_surfaces(struct brw_context *brw )
+static enum pipe_error prepare_wm_surfaces(struct brw_context *brw )
 {
-   GLuint i;
+   enum pipe_error ret;
    int nr_surfaces = 0;
-
-   /* Unreference old buffers
-    */
-   for (i = 0; i < brw->wm.nr_surfaces; i++) {
-      brw->sws->bo_unreference(brw->wm.surf_bo[i]);
-      brw->wm.surf_bo[i] = NULL;
-   }
-
+   GLuint i;
 
    /* PIPE_NEW_COLOR_BUFFERS | PIPE_NEW_BLEND
     *
@@ -192,38 +207,51 @@ static int prepare_wm_surfaces(struct brw_context *brw )
     * XXX: no color buffer case
     */
    for (i = 0; i < brw->curr.fb.nr_cbufs; i++) {
-      brw_update_renderbuffer_surface(brw, 
-				      brw_surface(brw->curr.fb.cbufs[i]), 
-				      nr_surfaces++);
+      ret = brw_update_render_surface(brw, 
+                                      brw_surface(brw->curr.fb.cbufs[i]), 
+                                      &brw->wm.surf_bo[nr_surfaces++]);
+      if (ret)
+         return ret;
    }
 
    /* PIPE_NEW_TEXTURE 
     */
    for (i = 0; i < brw->curr.num_textures; i++) {
-      brw_update_texture_surface(brw, 
-				 brw_texture(brw->curr.texture[i]),
-				 nr_surfaces++);
+      ret = brw_update_texture_surface(brw, 
+                                       brw_texture(brw->curr.texture[i]),
+                                       &brw->wm.surf_bo[nr_surfaces++]);
+      if (ret)
+         return ret;
    }
 
    /* PIPE_NEW_FRAGMENT_CONSTANTS
     */
 #if 0
    if (brw->curr.fragment_constants) {
-      brw_update_fragment_constant_surface(brw, 
-					   brw->curr.fragment_constants, 
-					   nr_surfaces++);
+      ret = brw_update_fragment_constant_surface(brw, 
+                                                 brw->curr.fragment_constants, 
+                                                 &brw->wm.surf_bo[nr_surfaces++]);
+      if (ret)
+         return ret;
    }
 #endif
 
    if (brw->wm.nr_surfaces != nr_surfaces) {
+
+      /* Unreference any left-over old buffers
+       */
+      for (i = nr_surfaces; i < brw->wm.nr_surfaces; i++)
+         bo_reference(&brw->wm.surf_bo[i], NULL);
+
       brw->wm.nr_surfaces = nr_surfaces;
       brw->state.dirty.brw |= BRW_NEW_NR_WM_SURFACES;
    }
 
-   brw->sws->bo_unreference(brw->wm.bind_bo);
-   brw->wm.bind_bo = brw_wm_get_binding_table(brw);
+   ret = brw_wm_get_binding_table(brw, &brw->wm.bind_bo);
+   if (ret)
+      return ret;
 
-   return 0;
+   return PIPE_OK;
 }
 
 const struct brw_tracked_state brw_wm_surfaces = {