From: Chad Versace <chad.versace@linux.intel.com>
Date: Wed, 16 Nov 2011 22:04:25 +0000 (-0800)
Subject: intel: Replace intel_renderbuffer::region with a miptree [v3]
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=da2816a45e6e3a33246a341fee72e6f893f315d9;p=mesa.git

intel: Replace intel_renderbuffer::region with a miptree [v3]

Essentially, this patch just globally substitutes `irb->region` with
`irb->mt->region` and then does some minor cleanups to avoid segfaults
and other problems.

This is in preparation for
  1. Fixing scatter/gather for mipmapped separate stencil textures.
  2. Supporting HiZ for mipmapped depth textures.

As a nice benefit, this lays down some preliminary groundwork for easily
texturing from any renderbuffer, even those of the window system.

A future commit will replace intel_mipmap_tree::hiz_region with a miptree.

v2:
   - Return early in intel_process_dri2_buffer_*() if region allocation
     fails.
   - Fix double semicolon.
   - Fix miptree reference leaks in the following functions:
       intel_process_dri2_buffer_with_separate_stencil()
       intel_image_target_renderbuffer_storage()

v3:
   - [anholt] Fix check for hiz allocation failure. Replace
     ``if (!irb->mt)` with ``if(!irb->mt->hiz_region)``.

Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Signed-off-by: Chad Versace <chad.versace@linux.intel.com>
---

diff --git a/src/mesa/drivers/dri/i965/brw_misc_state.c b/src/mesa/drivers/dri/i965/brw_misc_state.c
index 514c990ed25..4119afa4c49 100644
--- a/src/mesa/drivers/dri/i965/brw_misc_state.c
+++ b/src/mesa/drivers/dri/i965/brw_misc_state.c
@@ -33,6 +33,7 @@
 
 #include "intel_batchbuffer.h"
 #include "intel_fbo.h"
+#include "intel_mipmap_tree.h"
 #include "intel_regions.h"
 
 #include "brw_context.h"
@@ -204,9 +205,14 @@ static void emit_depthbuffer(struct brw_context *brw)
    /* _NEW_BUFFERS */
    struct intel_renderbuffer *depth_irb = intel_get_renderbuffer(fb, BUFFER_DEPTH);
    struct intel_renderbuffer *stencil_irb = intel_get_renderbuffer(fb, BUFFER_STENCIL);
-   struct intel_region *hiz_region = depth_irb ? depth_irb->hiz_region : NULL;
+   struct intel_region *hiz_region = NULL;
    unsigned int len;
 
+   if (depth_irb &&
+       depth_irb->mt) {
+      hiz_region = depth_irb->mt->hiz_region;
+   }
+
    /* 3DSTATE_DEPTH_BUFFER, 3DSTATE_STENCIL_BUFFER are both
     * non-pipelined state that will need the PIPE_CONTROL workaround.
     */
@@ -272,6 +278,8 @@ static void emit_depthbuffer(struct brw_context *brw)
        *     [DevGT]: This field must be set to the same value (enabled or
        *     disabled) as Hierarchical Depth Buffer Enable
        */
+      struct intel_region *region = stencil_irb->mt->region;
+
       assert(intel->has_separate_stencil);
       assert(stencil_irb->Base.Format == MESA_FORMAT_S8);
 
@@ -283,8 +291,8 @@ static void emit_depthbuffer(struct brw_context *brw)
 	        (BRW_TILEWALK_YMAJOR << 26) |
 	        (BRW_SURFACE_2D << 29));
       OUT_BATCH(0);
-      OUT_BATCH(((stencil_irb->region->width - 1) << 6) |
-	         (2 * stencil_irb->region->height - 1) << 19);
+      OUT_BATCH(((region->width - 1) << 6) |
+	         (2 * region->height - 1) << 19);
       OUT_BATCH(0);
       OUT_BATCH(0);
 
@@ -294,7 +302,7 @@ static void emit_depthbuffer(struct brw_context *brw)
       ADVANCE_BATCH();
 
    } else {
-      struct intel_region *region = depth_irb->region;
+      struct intel_region *region = depth_irb->mt->region;
       unsigned int format;
       uint32_t tile_x, tile_y, offset;
 
@@ -379,10 +387,11 @@ static void emit_depthbuffer(struct brw_context *brw)
 
       /* Emit stencil buffer. */
       if (stencil_irb) {
+	 struct intel_region *region = stencil_irb->mt->region;
 	 BEGIN_BATCH(3);
 	 OUT_BATCH((_3DSTATE_STENCIL_BUFFER << 16) | (3 - 2));
-	 OUT_BATCH(stencil_irb->region->pitch * stencil_irb->region->cpp - 1);
-	 OUT_RELOC(stencil_irb->region->bo,
+	 OUT_BATCH(region->pitch * region->cpp - 1);
+	 OUT_RELOC(region->bo,
 		   I915_GEM_DOMAIN_RENDER, I915_GEM_DOMAIN_RENDER,
 		   0);
 	 ADVANCE_BATCH();
diff --git a/src/mesa/drivers/dri/i965/brw_vtbl.c b/src/mesa/drivers/dri/i965/brw_vtbl.c
index 7c23faa8fff..9302b276347 100644
--- a/src/mesa/drivers/dri/i965/brw_vtbl.c
+++ b/src/mesa/drivers/dri/i965/brw_vtbl.c
@@ -126,7 +126,7 @@ brw_update_draw_buffer(struct intel_context *intel)
    /* Check some stencil invariants.  These should probably be in
     * emit_depthbuffer().
     */
-   if (irbStencil && irbStencil->region) {
+   if (irbStencil && irbStencil->mt) {
       if (!intel->has_separate_stencil)
 	 assert(irbStencil->Base.Format == MESA_FORMAT_S8_Z24);
       if (fb_has_hiz || intel->must_use_separate_stencil)
diff --git a/src/mesa/drivers/dri/i965/brw_wm_surface_state.c b/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
index 0cc62017cbe..0c2c804b133 100644
--- a/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
+++ b/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
@@ -447,7 +447,7 @@ brw_update_renderbuffer_surface(struct brw_context *brw,
    struct intel_context *intel = &brw->intel;
    struct gl_context *ctx = &intel->ctx;
    struct intel_renderbuffer *irb = intel_renderbuffer(rb);
-   struct intel_region *region = irb->region;
+   struct intel_region *region = irb->mt->region;
    uint32_t *surf;
    uint32_t tile_x, tile_y;
    uint32_t format = 0;
diff --git a/src/mesa/drivers/dri/i965/gen7_misc_state.c b/src/mesa/drivers/dri/i965/gen7_misc_state.c
index 6a3c086ac96..25e1b1d0fe1 100644
--- a/src/mesa/drivers/dri/i965/gen7_misc_state.c
+++ b/src/mesa/drivers/dri/i965/gen7_misc_state.c
@@ -22,6 +22,7 @@
  */
 
 #include "intel_batchbuffer.h"
+#include "intel_mipmap_tree.h"
 #include "intel_regions.h"
 #include "intel_fbo.h"
 #include "brw_context.h"
@@ -38,7 +39,7 @@ gen7_depth_format(struct brw_context *brw)
    struct intel_region *region = NULL;
 
    if (drb)
-      region = drb->region;
+      region = drb->mt->region;
    else
       return BRW_DEPTHFORMAT_D32_FLOAT;
 
@@ -78,7 +79,7 @@ static void emit_depthbuffer(struct brw_context *brw)
       if (srb == NULL) {
 	 dw1 |= (BRW_SURFACE_NULL << 29);
       } else {
-	 struct intel_region *region = srb->region;
+	 struct intel_region *region = srb->mt->region;
 
 	 /* _NEW_STENCIL: enable stencil buffer writes */
 	 dw1 |= ((ctx->Stencil.WriteMask != 0) << 27);
@@ -98,7 +99,7 @@ static void emit_depthbuffer(struct brw_context *brw)
       OUT_BATCH(0);
       ADVANCE_BATCH();
    } else {
-      struct intel_region *region = drb->region;
+      struct intel_region *region = drb->mt->region;
       uint32_t tile_x, tile_y, offset;
 
       offset = intel_renderbuffer_tile_offsets(drb, &tile_x, &tile_y);
@@ -140,8 +141,8 @@ static void emit_depthbuffer(struct brw_context *brw)
    } else {
       BEGIN_BATCH(3);
       OUT_BATCH(GEN7_3DSTATE_STENCIL_BUFFER << 16 | (3 - 2));
-      OUT_BATCH(srb->region->pitch * srb->region->cpp - 1);
-      OUT_RELOC(srb->region->bo,
+      OUT_BATCH(srb->mt->region->pitch * srb->mt->region->cpp - 1);
+      OUT_RELOC(srb->mt->region->bo,
 	        I915_GEM_DOMAIN_RENDER, I915_GEM_DOMAIN_RENDER,
 		0);
       ADVANCE_BATCH();
diff --git a/src/mesa/drivers/dri/i965/gen7_wm_surface_state.c b/src/mesa/drivers/dri/i965/gen7_wm_surface_state.c
index f74198b2468..e1c3910af95 100644
--- a/src/mesa/drivers/dri/i965/gen7_wm_surface_state.c
+++ b/src/mesa/drivers/dri/i965/gen7_wm_surface_state.c
@@ -192,7 +192,7 @@ gen7_update_renderbuffer_surface(struct brw_context *brw,
    struct intel_context *intel = &brw->intel;
    struct gl_context *ctx = &intel->ctx;
    struct intel_renderbuffer *irb = intel_renderbuffer(rb);
-   struct intel_region *region = irb->region;
+   struct intel_region *region = irb->mt->region;
    struct gen7_surface_state *surf;
    uint32_t tile_x, tile_y;
 
diff --git a/src/mesa/drivers/dri/intel/intel_blit.c b/src/mesa/drivers/dri/intel/intel_blit.c
index 8d7693d7b88..b1a839ac706 100644
--- a/src/mesa/drivers/dri/intel/intel_blit.c
+++ b/src/mesa/drivers/dri/intel/intel_blit.c
@@ -267,13 +267,18 @@ intelClearWithBlit(struct gl_context *ctx, GLbitfield mask)
       int x1, y1, x2, y2;
       uint32_t clear_val;
       uint32_t BR13, CMD;
+      struct intel_region *region;
       int pitch, cpp;
       drm_intel_bo *aper_array[2];
 
       mask &= ~(1 << buf);
 
       irb = intel_get_renderbuffer(fb, buf);
-      if (irb == NULL || irb->region == NULL || irb->region->bo == NULL) {
+      if (irb && irb->mt) {
+	 region = irb->mt->region;
+	 assert(region);
+	 assert(region->bo);
+      } else {
          fail_mask |= 1 << buf;
          continue;
       }
@@ -284,12 +289,12 @@ intelClearWithBlit(struct gl_context *ctx, GLbitfield mask)
       x2 = cx + cw + irb->draw_x;
       y2 = cy + ch + irb->draw_y;
 
-      pitch = irb->region->pitch;
-      cpp = irb->region->cpp;
+      pitch = region->pitch;
+      cpp = region->cpp;
 
       DBG("%s dst:buf(%p)/%d %d,%d sz:%dx%d\n",
 	  __FUNCTION__,
-	  irb->region->bo, (pitch * cpp),
+	  region->bo, (pitch * cpp),
 	  x1, y1, x2 - x1, y2 - y1);
 
       BR13 = 0xf0 << 16;
@@ -305,10 +310,10 @@ intelClearWithBlit(struct gl_context *ctx, GLbitfield mask)
 	 }
       }
 
-      assert(irb->region->tiling != I915_TILING_Y);
+      assert(region->tiling != I915_TILING_Y);
 
 #ifndef I915
-      if (irb->region->tiling != I915_TILING_NONE) {
+      if (region->tiling != I915_TILING_NONE) {
 	 CMD |= XY_DST_TILED;
 	 pitch /= 4;
       }
@@ -357,7 +362,7 @@ intelClearWithBlit(struct gl_context *ctx, GLbitfield mask)
 
       /* do space check before going any further */
       aper_array[0] = intel->batch.bo;
-      aper_array[1] = irb->region->bo;
+      aper_array[1] = region->bo;
 
       if (drm_intel_bufmgr_check_aperture_space(aper_array,
 						ARRAY_SIZE(aper_array)) != 0) {
@@ -369,7 +374,7 @@ intelClearWithBlit(struct gl_context *ctx, GLbitfield mask)
       OUT_BATCH(BR13);
       OUT_BATCH((y1 << 16) | x1);
       OUT_BATCH((y2 << 16) | x2);
-      OUT_RELOC_FENCED(irb->region->bo,
+      OUT_RELOC_FENCED(region->bo,
 		       I915_GEM_DOMAIN_RENDER, I915_GEM_DOMAIN_RENDER,
 		       0);
       OUT_BATCH(clear_val);
diff --git a/src/mesa/drivers/dri/intel/intel_buffer_objects.c b/src/mesa/drivers/dri/intel/intel_buffer_objects.c
index 75d95b1fe70..4a1a8165be5 100644
--- a/src/mesa/drivers/dri/intel/intel_buffer_objects.c
+++ b/src/mesa/drivers/dri/intel/intel_buffer_objects.c
@@ -766,10 +766,10 @@ intel_render_object_purgeable(struct gl_context * ctx,
    (void) option;
 
    intel = intel_renderbuffer(obj);
-   if (intel->region == NULL)
+   if (intel->mt == NULL)
       return GL_RELEASED_APPLE;
 
-   return intel_buffer_purgeable(intel->region->bo);
+   return intel_buffer_purgeable(intel->mt->region->bo);
 }
 
 static GLenum
@@ -823,10 +823,10 @@ intel_render_object_unpurgeable(struct gl_context * ctx,
    (void) option;
 
    intel = intel_renderbuffer(obj);
-   if (intel->region == NULL)
+   if (intel->mt == NULL)
       return GL_UNDEFINED_APPLE;
 
-   return intel_buffer_unpurgeable(intel->region->bo);
+   return intel_buffer_unpurgeable(intel->mt->region->bo);
 }
 #endif
 
diff --git a/src/mesa/drivers/dri/intel/intel_buffers.c b/src/mesa/drivers/dri/intel/intel_buffers.c
index 08f5c4decd3..4632751935a 100644
--- a/src/mesa/drivers/dri/intel/intel_buffers.c
+++ b/src/mesa/drivers/dri/intel/intel_buffers.c
@@ -28,6 +28,7 @@
 #include "intel_context.h"
 #include "intel_buffers.h"
 #include "intel_fbo.h"
+#include "intel_mipmap_tree.h"
 
 #include "main/framebuffer.h"
 #include "main/renderbuffer.h"
@@ -40,8 +41,8 @@ intel_drawbuf_region(struct intel_context *intel)
 {
    struct intel_renderbuffer *irbColor =
       intel_renderbuffer(intel->ctx.DrawBuffer->_ColorDrawBuffers[0]);
-   if (irbColor)
-      return irbColor->region;
+   if (irbColor && irbColor->mt)
+      return irbColor->mt->region;
    else
       return NULL;
 }
@@ -54,8 +55,8 @@ intel_readbuf_region(struct intel_context *intel)
 {
    struct intel_renderbuffer *irb
       = intel_renderbuffer(intel->ctx.ReadBuffer->_ColorReadBuffer);
-   if (irb)
-      return irb->region;
+   if (irb && irb->mt)
+      return irb->mt->region;
    else
       return NULL;
 }
diff --git a/src/mesa/drivers/dri/intel/intel_context.c b/src/mesa/drivers/dri/intel/intel_context.c
index d89b38875b8..3f55c512357 100644
--- a/src/mesa/drivers/dri/intel/intel_context.c
+++ b/src/mesa/drivers/dri/intel/intel_context.c
@@ -53,6 +53,7 @@
 #include "intel_fbo.h"
 #include "intel_bufmgr.h"
 #include "intel_screen.h"
+#include "intel_mipmap_tree.h"
 
 #include "utils.h"
 #include "../glsl/ralloc.h"
@@ -1153,7 +1154,9 @@ intel_process_dri2_buffer_no_separate_stencil(struct intel_context *intel,
    if (!rb)
       return;
 
-   if (rb->region && rb->region->name == buffer->name)
+   if (rb->mt &&
+       rb->mt->region &&
+       rb->mt->region->name == buffer->name)
       return;
 
    if (unlikely(INTEL_DEBUG & DEBUG_DRI)) {
@@ -1167,23 +1170,34 @@ intel_process_dri2_buffer_no_separate_stencil(struct intel_context *intel,
    if (buffer->attachment == __DRI_BUFFER_STENCIL) {
       struct intel_renderbuffer *depth_rb =
 	 intel_get_renderbuffer(fb, BUFFER_DEPTH);
-      identify_depth_and_stencil = depth_rb && depth_rb->region;
+      identify_depth_and_stencil = depth_rb && depth_rb->mt;
    }
 
    if (identify_depth_and_stencil) {
       if (unlikely(INTEL_DEBUG & DEBUG_DRI)) {
 	 fprintf(stderr, "(reusing depth buffer as stencil)\n");
       }
-      intel_region_reference(&rb->region, depth_rb->region);
+      intel_miptree_reference(&rb->mt, depth_rb->mt);
    } else {
-      intel_region_release(&rb->region);
-      rb->region = intel_region_alloc_for_handle(intel->intelScreen,
+      intel_miptree_release(&rb->mt);
+      struct intel_region *region =
+                   intel_region_alloc_for_handle(intel->intelScreen,
 						 buffer->cpp,
 						 drawable->w,
 						 drawable->h,
 						 buffer->pitch / buffer->cpp,
 						 buffer->name,
 						 buffer_name);
+      if (!region)
+	 return;
+
+      rb->mt = intel_miptree_create_for_region(intel,
+                                               GL_TEXTURE_2D,
+                                               rb->Base.Format,
+                                               region);
+      intel_region_release(&region);
+      if (!rb->mt)
+	 return;
    }
 
    if (buffer->attachment == __DRI_BUFFER_DEPTH_STENCIL) {
@@ -1196,7 +1210,7 @@ intel_process_dri2_buffer_no_separate_stencil(struct intel_context *intel,
       /* The rb passed in is the BUFFER_DEPTH attachment, and we need
        * to associate this region to BUFFER_STENCIL as well.
        */
-      intel_region_reference(&stencil_rb->region, rb->region);
+      intel_miptree_reference(&stencil_rb->mt, rb->mt);
    }
 }
 
@@ -1338,11 +1352,13 @@ intel_process_dri2_buffer_with_separate_stencil(struct intel_context *intel,
 
    /* If the renderbuffer's and DRIbuffer's regions match, then continue. */
    if ((buffer->attachment != __DRI_BUFFER_HIZ &&
-	rb->region &&
-	rb->region->name == buffer->name) ||
+	rb->mt &&
+	rb->mt->region &&
+	rb->mt->region->name == buffer->name) ||
        (buffer->attachment == __DRI_BUFFER_HIZ &&
-	rb->hiz_region &&
-	rb->hiz_region->name == buffer->name)) {
+	rb->mt &&
+	rb->mt->hiz_region &&
+	rb->mt->hiz_region->name == buffer->name)) {
       return;
    }
 
@@ -1371,6 +1387,15 @@ intel_process_dri2_buffer_with_separate_stencil(struct intel_context *intel,
        buffer_height = drawable->h;
    }
 
+   /* Release the buffer storage now in case we have to return early
+    * due to region allocation failure.
+    */
+   if (buffer->attachment == __DRI_BUFFER_HIZ) {
+      intel_region_release(&rb->mt->hiz_region);
+   } else {
+      intel_miptree_release(&rb->mt);
+   }
+
    struct intel_region *region =
       intel_region_alloc_for_handle(intel->intelScreen,
 				    buffer->cpp,
@@ -1379,14 +1404,19 @@ intel_process_dri2_buffer_with_separate_stencil(struct intel_context *intel,
 				    buffer->pitch / buffer->cpp,
 				    buffer->name,
 				    buffer_name);
+   if (!region)
+      return;
 
+   /* Associate buffer with new storage. */
    if (buffer->attachment == __DRI_BUFFER_HIZ) {
-      intel_region_reference(&rb->hiz_region, region);
+      rb->mt->hiz_region = region;
    } else {
-      intel_region_reference(&rb->region, region);
+      rb->mt = intel_miptree_create_for_region(intel,
+                                               GL_TEXTURE_2D,
+                                               rb->Base.Format,
+                                               region);
+      intel_region_release(&region);
    }
-
-   intel_region_release(&region);
 }
 
 /**
@@ -1463,7 +1493,7 @@ intel_verify_dri2_has_hiz(struct intel_context *intel,
       assert(stencil_rb->Base.Format == MESA_FORMAT_S8);
       assert(depth_rb && depth_rb->Base.Format == MESA_FORMAT_X8_Z24);
 
-      if (stencil_rb->region->tiling == I915_TILING_NONE) {
+      if (stencil_rb->mt->region->tiling == I915_TILING_NONE) {
 	 /*
 	  * The stencil buffer is actually W tiled. The region's tiling is
 	  * I915_TILING_NONE, however, because the GTT is incapable of W
@@ -1544,11 +1574,21 @@ intel_verify_dri2_has_hiz(struct intel_context *intel,
 					     / depth_stencil_buffer->cpp,
 					  depth_stencil_buffer->name,
 					  "dri2 depth / stencil buffer");
-	 intel_region_reference(&intel_get_renderbuffer(fb, BUFFER_DEPTH)->region,
-				region);
-	 intel_region_reference(&intel_get_renderbuffer(fb, BUFFER_STENCIL)->region,
-				region);
+	 if (!region)
+	    return;
+
+	 struct intel_mipmap_tree *mt =
+	       intel_miptree_create_for_region(intel,
+	                                       GL_TEXTURE_2D,
+	                                       depth_stencil_rb->Base.Format,
+	                                       region);
 	 intel_region_release(&region);
+	 if (!mt)
+	    return;
+
+	 intel_miptree_reference(&intel_get_renderbuffer(fb, BUFFER_DEPTH)->mt, mt);
+	 intel_miptree_reference(&intel_get_renderbuffer(fb, BUFFER_STENCIL)->mt, mt);
+	 intel_miptree_release(&mt);
       }
    }
 
diff --git a/src/mesa/drivers/dri/intel/intel_fbo.c b/src/mesa/drivers/dri/intel/intel_fbo.c
index 429529c81c4..e5328df2ff5 100644
--- a/src/mesa/drivers/dri/intel/intel_fbo.c
+++ b/src/mesa/drivers/dri/intel/intel_fbo.c
@@ -61,15 +61,15 @@ intel_framebuffer_has_hiz(struct gl_framebuffer *fb)
    struct intel_renderbuffer *rb = NULL;
    if (fb)
       rb = intel_get_renderbuffer(fb, BUFFER_DEPTH);
-   return rb && rb->hiz_region;
+   return rb && rb->mt && rb->mt->hiz_region;
 }
 
 struct intel_region*
 intel_get_rb_region(struct gl_framebuffer *fb, GLuint attIndex)
 {
    struct intel_renderbuffer *irb = intel_get_renderbuffer(fb, attIndex);
-   if (irb)
-      return irb->region;
+   if (irb && irb->mt)
+      return irb->mt->region;
    else
       return NULL;
 }
@@ -95,8 +95,7 @@ intel_delete_renderbuffer(struct gl_renderbuffer *rb)
 
    ASSERT(irb);
 
-   intel_region_release(&irb->region);
-   intel_region_release(&irb->hiz_region);
+   intel_miptree_release(&irb->mt);
 
    _mesa_reference_renderbuffer(&irb->wrapped_depth, NULL);
    _mesa_reference_renderbuffer(&irb->wrapped_stencil, NULL);
@@ -122,7 +121,7 @@ intel_map_renderbuffer_gtt(struct gl_context *ctx,
    GLubyte *map;
    int stride, flip_stride;
 
-   assert(irb->region);
+   assert(irb->mt);
 
    irb->map_mode = mode;
    irb->map_x = x;
@@ -130,10 +129,10 @@ intel_map_renderbuffer_gtt(struct gl_context *ctx,
    irb->map_w = w;
    irb->map_h = h;
 
-   stride = irb->region->pitch * irb->region->cpp;
+   stride = irb->mt->region->pitch * irb->mt->region->cpp;
 
    if (rb->Name == 0) {
-      y = irb->region->height - 1 - y;
+      y = irb->mt->region->height - 1 - y;
       flip_stride = -stride;
    } else {
       x += irb->draw_x;
@@ -141,14 +140,14 @@ intel_map_renderbuffer_gtt(struct gl_context *ctx,
       flip_stride = stride;
    }
 
-   if (drm_intel_bo_references(intel->batch.bo, irb->region->bo)) {
+   if (drm_intel_bo_references(intel->batch.bo, irb->mt->region->bo)) {
       intel_batchbuffer_flush(intel);
    }
 
-   drm_intel_gem_bo_map_gtt(irb->region->bo);
+   drm_intel_gem_bo_map_gtt(irb->mt->region->bo);
 
-   map = irb->region->bo->virtual;
-   map += x * irb->region->cpp;
+   map = irb->mt->region->bo->virtual;
+   map += x * irb->mt->region->cpp;
    map += (int)y * stride;
 
    *out_map = map;
@@ -186,10 +185,10 @@ intel_map_renderbuffer_blit(struct gl_context *ctx,
    int src_x, src_y;
    int dst_stride;
 
-   assert(irb->region);
+   assert(irb->mt->region);
    assert(intel->gen >= 6);
    assert(!(mode & GL_MAP_WRITE_BIT));
-   assert(irb->region->tiling == I915_TILING_X);
+   assert(irb->mt->region->tiling == I915_TILING_X);
 
    irb->map_mode = mode;
    irb->map_x = x;
@@ -197,14 +196,14 @@ intel_map_renderbuffer_blit(struct gl_context *ctx,
    irb->map_w = w;
    irb->map_h = h;
 
-   dst_stride = ALIGN(w * irb->region->cpp, 4);
+   dst_stride = ALIGN(w * irb->mt->region->cpp, 4);
 
    if (rb->Name) {
       src_x = x + irb->draw_x;
       src_y = y + irb->draw_y;
    } else {
       src_x = x;
-      src_y = irb->region->height - y - h;
+      src_y = irb->mt->region->height - y - h;
    }
 
    irb->map_bo = drm_intel_bo_alloc(intel->bufmgr, "MapRenderbuffer() temp",
@@ -215,10 +214,10 @@ intel_map_renderbuffer_blit(struct gl_context *ctx,
     */
    if (irb->map_bo &&
        intelEmitCopyBlit(intel,
-			 irb->region->cpp,
-			 irb->region->pitch, irb->region->bo,
-			 0, irb->region->tiling,
-			 dst_stride / irb->region->cpp, irb->map_bo,
+			 irb->mt->region->cpp,
+			 irb->mt->region->pitch, irb->mt->region->bo,
+			 0, irb->mt->region->tiling,
+			 dst_stride / irb->mt->region->cpp, irb->map_bo,
 			 0, I915_TILING_NONE,
 			 src_x, src_y,
 			 0, 0,
@@ -277,7 +276,7 @@ intel_map_renderbuffer_s8(struct gl_context *ctx,
    uint8_t *untiled_s8_map;
 
    assert(rb->Format == MESA_FORMAT_S8);
-   assert(irb->region);
+   assert(irb->mt);
 
    irb->map_mode = mode;
    irb->map_x = x;
@@ -291,12 +290,12 @@ intel_map_renderbuffer_s8(struct gl_context *ctx,
 
    irb->map_buffer = malloc(w * h);
    untiled_s8_map = irb->map_buffer;
-   tiled_s8_map = intel_region_map(intel, irb->region, mode);
+   tiled_s8_map = intel_region_map(intel, irb->mt->region, mode);
 
    for (uint32_t pix_y = 0; pix_y < h; pix_y++) {
       for (uint32_t pix_x = 0; pix_x < w; pix_x++) {
 	 uint32_t flipped_y = y_flip * (int32_t)(y + pix_y) + y_bias;
-	 ptrdiff_t offset = intel_offset_S8(irb->region->pitch,
+	 ptrdiff_t offset = intel_offset_S8(irb->mt->region->pitch,
 	                                    x + pix_x,
 	                                    flipped_y);
 	 untiled_s8_map[pix_y * w + pix_x] = tiled_s8_map[offset];
@@ -363,12 +362,12 @@ intel_map_renderbuffer_separate_s8z24(struct gl_context *ctx,
 			       &s8z24_map, &s8z24_stride);
 
    s8_irb = intel_renderbuffer(irb->wrapped_stencil);
-   s8_map = intel_region_map(intel, s8_irb->region, GL_MAP_READ_BIT);
+   s8_map = intel_region_map(intel, s8_irb->mt->region, GL_MAP_READ_BIT);
 
    /* Gather the stencil buffer into the depth buffer. */
    for (uint32_t pix_y = 0; pix_y < h; ++pix_y) {
       for (uint32_t pix_x = 0; pix_x < w; ++pix_x) {
-	 ptrdiff_t s8_offset = intel_offset_S8(s8_irb->region->pitch,
+	 ptrdiff_t s8_offset = intel_offset_S8(s8_irb->mt->region->pitch,
 					       x + pix_x,
 					       y + pix_y);
 	 ptrdiff_t s8z24_offset = pix_y * s8z24_stride
@@ -378,7 +377,7 @@ intel_map_renderbuffer_separate_s8z24(struct gl_context *ctx,
       }
    }
 
-   intel_region_unmap(intel, s8_irb->region);
+   intel_region_unmap(intel, s8_irb->mt->region);
 
    *out_map = s8z24_map;
    *out_stride = s8z24_stride;
@@ -399,7 +398,7 @@ intel_map_renderbuffer(struct gl_context *ctx,
    struct intel_renderbuffer *irb = intel_renderbuffer(rb);
 
    /* We sometimes get called with this by our intel_span.c usage. */
-   if (!irb->region && !irb->wrapped_depth) {
+   if (!irb->mt && !irb->wrapped_depth) {
       *out_map = NULL;
       *out_stride = 0;
       return;
@@ -413,7 +412,7 @@ intel_map_renderbuffer(struct gl_context *ctx,
 					    out_map, out_stride);
    } else if (intel->gen >= 6 &&
 	      !(mode & GL_MAP_WRITE_BIT) &&
-	      irb->region->tiling == I915_TILING_X) {
+	      irb->mt->region->tiling == I915_TILING_X) {
       intel_map_renderbuffer_blit(ctx, rb, x, y, w, h, mode,
 				  out_map, out_stride);
    } else {
@@ -445,7 +444,7 @@ intel_unmap_renderbuffer_s8(struct gl_context *ctx,
        * the real buffer.
        */
       uint8_t *untiled_s8_map = irb->map_buffer;
-      uint8_t *tiled_s8_map = irb->region->bo->virtual;
+      uint8_t *tiled_s8_map = irb->mt->region->bo->virtual;
 
       /* Flip the Y axis for the default framebuffer. */
       int y_flip = (rb->Name == 0) ? -1 : 1;
@@ -454,7 +453,7 @@ intel_unmap_renderbuffer_s8(struct gl_context *ctx,
       for (uint32_t pix_y = 0; pix_y < irb->map_h; pix_y++) {
 	 for (uint32_t pix_x = 0; pix_x < irb->map_w; pix_x++) {
 	    uint32_t flipped_y = y_flip * (int32_t)(pix_y + irb->map_y) + y_bias;
-	    ptrdiff_t offset = intel_offset_S8(irb->region->pitch,
+	    ptrdiff_t offset = intel_offset_S8(irb->mt->region->pitch,
 	                                       pix_x + irb->map_x,
 	                                       flipped_y);
 	    tiled_s8_map[offset] =
@@ -463,7 +462,7 @@ intel_unmap_renderbuffer_s8(struct gl_context *ctx,
       }
    }
 
-   intel_region_unmap(intel, irb->region);
+   intel_region_unmap(intel, irb->mt->region);
    free(irb->map_buffer);
    irb->map_buffer = NULL;
 }
@@ -501,16 +500,16 @@ intel_unmap_renderbuffer_separate_s8z24(struct gl_context *ctx,
       uint8_t *s8_map;
       
       s8_irb = intel_renderbuffer(irb->wrapped_stencil);
-      s8_map = intel_region_map(intel, s8_irb->region, GL_MAP_WRITE_BIT);
+      s8_map = intel_region_map(intel, s8_irb->mt->region, GL_MAP_WRITE_BIT);
 
-      int32_t s8z24_stride = 4 * s8z24_irb->region->pitch;
-      uint8_t *s8z24_map = s8z24_irb->region->bo->virtual
+      int32_t s8z24_stride = 4 * s8z24_irb->mt->region->pitch;
+      uint8_t *s8z24_map = s8z24_irb->mt->region->bo->virtual
 			 + map_y * s8z24_stride
 			 + map_x * 4;
 
       for (uint32_t pix_y = 0; pix_y < map_h; ++pix_y) {
 	 for (uint32_t pix_x = 0; pix_x < map_w; ++pix_x) {
-	    ptrdiff_t s8_offset = intel_offset_S8(s8_irb->region->pitch,
+	    ptrdiff_t s8_offset = intel_offset_S8(s8_irb->mt->region->pitch,
 						  map_x + pix_x,
 						  map_y + pix_y);
 	    ptrdiff_t s8z24_offset = pix_y * s8z24_stride
@@ -520,10 +519,10 @@ intel_unmap_renderbuffer_separate_s8z24(struct gl_context *ctx,
 	 }
       }
 
-      intel_region_unmap(intel, s8_irb->region);
+      intel_region_unmap(intel, s8_irb->mt->region);
    }
 
-   drm_intel_gem_bo_unmap_gtt(s8z24_irb->region->bo);
+   drm_intel_gem_bo_unmap_gtt(s8z24_irb->mt->region->bo);
 }
 
 /**
@@ -549,11 +548,11 @@ intel_unmap_renderbuffer(struct gl_context *ctx,
       irb->map_bo = 0;
    } else {
       /* Paired with intel_map_renderbuffer_gtt(). */
-      if (irb->region) {
-	 /* The region may be null when intel_map_renderbuffer() is
+      if (irb->mt) {
+	 /* The miptree may be null when intel_map_renderbuffer() is
 	  * called from intel_span.c.
 	  */
-	 drm_intel_gem_bo_unmap_gtt(irb->region->bo);
+	 drm_intel_gem_bo_unmap_gtt(irb->mt->region->bo);
       }
    }
 }
@@ -620,13 +619,7 @@ intel_alloc_renderbuffer_storage(struct gl_context * ctx, struct gl_renderbuffer
 
    intel_flush(ctx);
 
-   /* free old region */
-   if (irb->region) {
-      intel_region_release(&irb->region);
-   }
-   if (irb->hiz_region) {
-      intel_region_release(&irb->hiz_region);
-   }
+   intel_miptree_release(&irb->mt);
 
    DBG("%s: %s: %s (%dx%d)\n", __FUNCTION__,
        _mesa_lookup_enum_by_nr(internalFormat),
@@ -658,14 +651,15 @@ intel_alloc_renderbuffer_storage(struct gl_context * ctx, struct gl_renderbuffer
        *
        * If we neglect to double the pitch, then render corruption occurs.
        */
-      irb->region = intel_region_alloc(intel->intelScreen,
-				       I915_TILING_NONE,
-				       cpp * 2,
-				       ALIGN(width, 64),
-				       ALIGN((height + 1) / 2, 64),
-				       true);
-      if (!irb->region)
-	return false;
+      irb->mt = intel_miptree_create_for_renderbuffer(
+		  intel,
+		  rb->Format,
+		  I915_TILING_NONE,
+		  cpp * 2,
+		  ALIGN(width, 64),
+		  ALIGN((height + 1) / 2, 64));
+      if (!irb->mt)
+	 return false;
 
    } else if (irb->Base.Format == MESA_FORMAT_S8_Z24
 	      && intel->must_use_separate_stencil) {
@@ -702,20 +696,21 @@ intel_alloc_renderbuffer_storage(struct gl_context * ctx, struct gl_renderbuffer
       _mesa_reference_renderbuffer(&irb->wrapped_stencil, stencil_rb);
 
    } else {
-      irb->region = intel_region_alloc(intel->intelScreen, tiling, cpp,
-				       width, height, true);
-      if (!irb->region)
+      irb->mt = intel_miptree_create_for_renderbuffer(intel, rb->Format,
+                                                      tiling, cpp,
+                                                      width, height);
+      if (!irb->mt)
 	 return false;
 
       if (intel->vtbl.is_hiz_depth_format(intel, rb->Format)) {
-	 irb->hiz_region = intel_region_alloc(intel->intelScreen,
-					      I915_TILING_Y,
-					      irb->region->cpp,
-					      irb->region->width,
-					      irb->region->height,
-					      true);
-	 if (!irb->hiz_region) {
-	    intel_region_release(&irb->region);
+	 irb->mt->hiz_region = intel_region_alloc(intel->intelScreen,
+	                                          I915_TILING_Y,
+	                                          cpp,
+	                                          rb->Width,
+	                                          rb->Height,
+	                                          true);
+	 if (!irb->mt->hiz_region) {
+	    intel_miptree_release(&irb->mt);
 	    return false;
 	 }
       }
@@ -754,7 +749,13 @@ intel_image_target_renderbuffer_storage(struct gl_context *ctx,
    }
 
    irb = intel_renderbuffer(rb);
-   intel_region_reference(&irb->region, image->region);
+   intel_miptree_release(&irb->mt);
+   irb->mt = intel_miptree_create_for_region(intel,
+                                             GL_TEXTURE_2D,
+                                             image->format,
+                                             image->region);
+   if (!irb->mt)
+      return;
 
    rb->InternalFormat = image->internal_format;
    rb->Width = image->region->width;
@@ -982,9 +983,8 @@ intel_update_wrapper(struct gl_context *ctx, struct intel_renderbuffer *irb,
       _mesa_reference_renderbuffer(&irb->wrapped_stencil,
 				   intel_image->stencil_rb);
    } else {
-      intel_region_reference(&irb->region, intel_image->mt->region);
+      intel_miptree_reference(&irb->mt, intel_image->mt);
    }
-
    return true;
 }
 
@@ -1050,20 +1050,21 @@ intel_renderbuffer_tile_offsets(struct intel_renderbuffer *irb,
 				uint32_t *tile_x,
 				uint32_t *tile_y)
 {
-   int cpp = irb->region->cpp;
-   uint32_t pitch = irb->region->pitch * cpp;
+   struct intel_region *region = irb->mt->region;
+   int cpp = region->cpp;
+   uint32_t pitch = region->pitch * cpp;
 
-   if (irb->region->tiling == I915_TILING_NONE) {
+   if (region->tiling == I915_TILING_NONE) {
       *tile_x = 0;
       *tile_y = 0;
       return irb->draw_x * cpp + irb->draw_y * pitch;
-   } else if (irb->region->tiling == I915_TILING_X) {
+   } else if (region->tiling == I915_TILING_X) {
       *tile_x = irb->draw_x % (512 / cpp);
       *tile_y = irb->draw_y % 8;
       return ((irb->draw_y / 8) * (8 * pitch) +
 	      (irb->draw_x - *tile_x) / (512 / cpp) * 4096);
    } else {
-      assert(irb->region->tiling == I915_TILING_Y);
+      assert(region->tiling == I915_TILING_Y);
       *tile_x = irb->draw_x % (128 / cpp);
       *tile_y = irb->draw_y % 32;
       return ((irb->draw_y / 32) * (32 * pitch) +
@@ -1164,7 +1165,7 @@ intel_render_texture(struct gl_context * ctx,
       intel_miptree_copy_teximage(intel, intel_image, new_mt);
       intel_renderbuffer_set_draw_offset(irb, intel_image, att->Zoffset);
 
-      intel_region_reference(&irb->region, intel_image->mt->region);
+      intel_miptree_reference(&irb->mt, intel_image->mt);
       intel_miptree_release(&new_mt);
    }
 #endif
diff --git a/src/mesa/drivers/dri/intel/intel_fbo.h b/src/mesa/drivers/dri/intel/intel_fbo.h
index 63da6659296..34d2f9a61cf 100644
--- a/src/mesa/drivers/dri/intel/intel_fbo.h
+++ b/src/mesa/drivers/dri/intel/intel_fbo.h
@@ -35,6 +35,7 @@
 #include "intel_screen.h"
 
 struct intel_context;
+struct intel_mipmap_tree;
 struct intel_texture_image;
 
 /**
@@ -43,15 +44,13 @@ struct intel_texture_image;
 struct intel_renderbuffer
 {
    struct gl_renderbuffer Base;
-   struct intel_region *region;
+   struct intel_mipmap_tree *mt; /**< The renderbuffer storage. */
    drm_intel_bo *map_bo;
+
    void *map_buffer;
    GLuint map_x, map_y, map_w, map_h;
    GLbitfield map_mode;
 
-   /** Only used by depth renderbuffers for which HiZ is enabled. */
-   struct intel_region *hiz_region;
-
    /**
     * \name Packed depth/stencil unwrappers
     *
diff --git a/src/mesa/drivers/dri/intel/intel_pixel_copy.c b/src/mesa/drivers/dri/intel/intel_pixel_copy.c
index 89d5c51ef15..2682e152abc 100644
--- a/src/mesa/drivers/dri/intel/intel_pixel_copy.c
+++ b/src/mesa/drivers/dri/intel/intel_pixel_copy.c
@@ -34,6 +34,7 @@
 
 #include "intel_context.h"
 #include "intel_buffers.h"
+#include "intel_mipmap_tree.h"
 #include "intel_regions.h"
 #include "intel_pixel.h"
 #include "intel_fbo.h"
@@ -188,8 +189,8 @@ do_blit_copypixels(struct gl_context * ctx,
    dsty += draw_irb->draw_y;
 
    if (!intel_region_copy(intel,
-			  draw_irb->region, 0, dstx, dsty,
-			  read_irb->region, 0, srcx, srcy,
+			  draw_irb->mt->region, 0, dstx, dsty,
+			  read_irb->mt->region, 0, srcx, srcy,
 			  width, height, flip,
 			  ctx->Color.ColorLogicOpEnabled ?
 			  ctx->Color.LogicOp : GL_COPY)) {
diff --git a/src/mesa/drivers/dri/intel/intel_screen.c b/src/mesa/drivers/dri/intel/intel_screen.c
index 5a73030660f..67dccdf6006 100644
--- a/src/mesa/drivers/dri/intel/intel_screen.c
+++ b/src/mesa/drivers/dri/intel/intel_screen.c
@@ -86,6 +86,7 @@ const GLuint __driNConfigOptions = 11;
 #include "intel_bufmgr.h"
 #include "intel_chipset.h"
 #include "intel_fbo.h"
+#include "intel_mipmap_tree.h"
 #include "intel_screen.h"
 #include "intel_tex.h"
 #include "intel_regions.h"
@@ -201,7 +202,7 @@ intel_create_image_from_renderbuffer(__DRIcontext *context,
    image->format = rb->Format;
    image->data_type = rb->DataType;
    image->data = loaderPrivate;
-   intel_region_reference(&image->region, irb->region);
+   intel_region_reference(&image->region, irb->mt->region);
 
    return image;
 }
diff --git a/src/mesa/drivers/dri/intel/intel_span.c b/src/mesa/drivers/dri/intel/intel_span.c
index b103bbd9f7f..83676b9313d 100644
--- a/src/mesa/drivers/dri/intel/intel_span.c
+++ b/src/mesa/drivers/dri/intel/intel_span.c
@@ -39,6 +39,7 @@
 
 #include "intel_buffers.h"
 #include "intel_fbo.h"
+#include "intel_mipmap_tree.h"
 #include "intel_screen.h"
 #include "intel_span.h"
 #include "intel_regions.h"
@@ -58,7 +59,7 @@ intel_set_span_functions(struct intel_context *intel,
    int minx = 0, miny = 0;						\
    int maxx = rb->Width;						\
    int maxy = rb->Height;						\
-   int pitch = rb->RowStride * irb->region->cpp;			\
+   int pitch = rb->RowStride * irb->mt->region->cpp;			\
    void *buf = rb->Data;						\
    GLuint p;								\
    (void) p;
diff --git a/src/mesa/drivers/dri/intel/intel_tex_copy.c b/src/mesa/drivers/dri/intel/intel_tex_copy.c
index 2df4ef6a7f6..543326a0580 100644
--- a/src/mesa/drivers/dri/intel/intel_tex_copy.c
+++ b/src/mesa/drivers/dri/intel/intel_tex_copy.c
@@ -71,6 +71,7 @@ intel_copy_texsubimage(struct intel_context *intel,
 {
    struct gl_context *ctx = &intel->ctx;
    struct intel_renderbuffer *irb;
+   struct intel_region *region;
    const GLenum internalFormat = intelImage->base.Base.InternalFormat;
    bool copy_supported = false;
    bool copy_supported_with_alpha_override = false;
@@ -78,11 +79,14 @@ intel_copy_texsubimage(struct intel_context *intel,
    intel_prepare_render(intel);
 
    irb = get_teximage_readbuffer(intel, internalFormat);
-   if (!intelImage->mt || !irb || !irb->region) {
+   if (!intelImage->mt || !irb || !irb->mt) {
       if (unlikely(INTEL_DEBUG & DEBUG_FALLBACKS))
 	 fprintf(stderr, "%s fail %p %p (0x%08x)\n",
 		 __FUNCTION__, intelImage->mt, irb, internalFormat);
       return false;
+   } else {
+      region = irb->mt->region;
+      assert(region);
    }
 
    copy_supported = intelImage->base.Base.TexFormat == irb->Base.Format;
@@ -127,19 +131,19 @@ intel_copy_texsubimage(struct intel_context *intel,
       if (ctx->ReadBuffer->Name == 0) {
 	 /* Flip vertical orientation for system framebuffers */
 	 y = ctx->ReadBuffer->Height - (y + height);
-	 src_pitch = -irb->region->pitch;
+	 src_pitch = -region->pitch;
       } else {
 	 /* reading from a FBO, y is already oriented the way we like */
-	 src_pitch = irb->region->pitch;
+	 src_pitch = region->pitch;
       }
 
       /* blit from src buffer to texture */
       if (!intelEmitCopyBlit(intel,
 			     intelImage->mt->cpp,
 			     src_pitch,
-			     irb->region->bo,
+			     region->bo,
 			     0,
-			     irb->region->tiling,
+			     region->tiling,
 			     intelImage->mt->region->pitch,
 			     intelImage->mt->region->bo,
 			     0,
diff --git a/src/mesa/drivers/dri/intel/intel_tex_image.c b/src/mesa/drivers/dri/intel/intel_tex_image.c
index 3fc2128536c..90e409094d5 100644
--- a/src/mesa/drivers/dri/intel/intel_tex_image.c
+++ b/src/mesa/drivers/dri/intel/intel_tex_image.c
@@ -306,7 +306,7 @@ intel_tex_image_s8z24_create_renderbuffers(struct intel_context *intel,
    idrb = intel_renderbuffer(drb);
    isrb = intel_renderbuffer(srb);
 
-   intel_region_reference(&idrb->region, image->mt->region);
+   intel_miptree_reference(&idrb->mt, image->mt);
    ok = intel_alloc_renderbuffer_storage(ctx, srb, GL_STENCIL_INDEX8,
 					 width, height);
 
@@ -471,7 +471,7 @@ intelSetTexBuffer2(__DRIcontext *pDRICtx, GLint target,
    /* If the region isn't set, then intel_update_renderbuffers was unable
     * to get the buffers for the drawable.
     */
-   if (rb->region == NULL)
+   if (!rb || !rb->mt)
       return;
 
    if (texture_format == __DRI_TEXTURE_FORMAT_RGB) {
@@ -485,7 +485,7 @@ intelSetTexBuffer2(__DRIcontext *pDRICtx, GLint target,
 
    _mesa_lock_texture(&intel->ctx, texObj);
    texImage = _mesa_get_tex_image(ctx, texObj, target, level);
-   intel_set_texture_image_region(ctx, texImage, rb->region, target,
+   intel_set_texture_image_region(ctx, texImage, rb->mt->region, target,
 				  internalFormat, texFormat);
    _mesa_unlock_texture(&intel->ctx, texObj);
 }