DD: Refactor BlitFramebuffer.

In preparation for glBlitNamedFramebuffer, the DD table function
BlitFramebuffer needs to accept two arbitrary framebuffer objects rather
than assuming ctx->ReadBuffer and ctx->DrawBuffer.

Reviewed-by: Jason Ekstrand <[email protected]>
Reviewed-by: Brian Paul <[email protected]>

20 files changed, 130 insertions, 83 deletions

diff --git a/src/mesa/drivers/common/meta.c b/src/mesa/drivers/common/meta.c
index 8b73cb99f3f..bb0073074e7 100644
--- a/src/mesa/drivers/common/meta.c
+++ b/src/mesa/drivers/common/meta.c
@@ -2793,7 +2793,8 @@ copytexsubimage_using_blit_framebuffer(struct gl_context *ctx, GLuint dims,
     * are too strict for CopyTexImage.  We know meta will be fine with format
     * changes.
     */
-   mask = _mesa_meta_BlitFramebuffer(ctx, x, y,
+   mask = _mesa_meta_BlitFramebuffer(ctx, ctx->ReadBuffer, ctx->DrawBuffer,
+                                     x, y,
                                      x + width, y + height,
                                      xoffset, yoffset,
                                      xoffset + width, yoffset + height,
diff --git a/src/mesa/drivers/common/meta.h b/src/mesa/drivers/common/meta.h
index 3b9e05e0176..e7d894df1d7 100644
--- a/src/mesa/drivers/common/meta.h
+++ b/src/mesa/drivers/common/meta.h
@@ -475,12 +475,16 @@ _mesa_meta_setup_sampler(struct gl_context *ctx,
 
 extern GLbitfield
 _mesa_meta_BlitFramebuffer(struct gl_context *ctx,
+                           const struct gl_framebuffer *readFb,
+                           const struct gl_framebuffer *drawFb,
                            GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
                            GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
                            GLbitfield mask, GLenum filter);
 
 extern void
 _mesa_meta_and_swrast_BlitFramebuffer(struct gl_context *ctx,
+                                      struct gl_framebuffer *readFb,
+                                      struct gl_framebuffer *drawFb,
                                       GLint srcX0, GLint srcY0,
                                       GLint srcX1, GLint srcY1,
                                       GLint dstX0, GLint dstY0,
diff --git a/src/mesa/drivers/common/meta_blit.c b/src/mesa/drivers/common/meta_blit.c
index 4212d94333a..3406be1ed1c 100644
--- a/src/mesa/drivers/common/meta_blit.c
+++ b/src/mesa/drivers/common/meta_blit.c
@@ -232,6 +232,7 @@ setup_glsl_msaa_blit_scaled_shader(struct gl_context *ctx,
 static void
 setup_glsl_msaa_blit_shader(struct gl_context *ctx,
                             struct blit_state *blit,
+                            const struct gl_framebuffer *drawFb,
                             struct gl_renderbuffer *src_rb,
                             GLenum target)
 {
@@ -267,7 +268,7 @@ setup_glsl_msaa_blit_shader(struct gl_context *ctx,
    /* Update the assert if we plan to support more than 16X MSAA. */
    assert(shader_offset >= 0 && shader_offset <= 4);
 
-   if (ctx->DrawBuffer->Visual.samples > 1) {
+   if (drawFb->Visual.samples > 1) {
       /* If you're calling meta_BlitFramebuffer with the destination
        * multisampled, this is the only path that will work -- swrast and
        * CopyTexImage won't work on it either.
@@ -508,6 +509,7 @@ setup_glsl_msaa_blit_shader(struct gl_context *ctx,
 static void
 setup_glsl_blit_framebuffer(struct gl_context *ctx,
                             struct blit_state *blit,
+                            const struct gl_framebuffer *drawFb,
                             struct gl_renderbuffer *src_rb,
                             GLenum target, GLenum filter,
                             bool is_scaled_blit,
@@ -530,7 +532,7 @@ setup_glsl_blit_framebuffer(struct gl_context *ctx,
    if (is_target_multisample && is_filter_scaled_resolve && is_scaled_blit) {
       setup_glsl_msaa_blit_scaled_shader(ctx, blit, src_rb, target, filter);
    } else if (is_target_multisample) {
-      setup_glsl_msaa_blit_shader(ctx, blit, src_rb, target);
+      setup_glsl_msaa_blit_shader(ctx, blit, drawFb, src_rb, target);
    } else {
       _mesa_meta_setup_blit_shader(ctx, target, do_depth,
                                    do_depth ? &blit->shaders_with_depth
@@ -546,12 +548,13 @@ setup_glsl_blit_framebuffer(struct gl_context *ctx,
  */
 static bool
 blitframebuffer_texture(struct gl_context *ctx,
+                        const struct gl_framebuffer *readFb,
+                        const struct gl_framebuffer *drawFb,
                         GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
                         GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
                         GLenum filter, GLint flipX, GLint flipY,
                         GLboolean glsl_version, GLboolean do_depth)
 {
-   const struct gl_framebuffer *readFb = ctx->ReadBuffer;
    int att_index = do_depth ? BUFFER_DEPTH : readFb->_ColorReadBufferIndex;
    const struct gl_renderbuffer_attachment *readAtt =
       &readFb->Attachment[att_index];
@@ -645,7 +648,7 @@ blitframebuffer_texture(struct gl_context *ctx,
    scaled_blit = dstW != srcW || dstH != srcH;
 
    if (glsl_version) {
-      setup_glsl_blit_framebuffer(ctx, blit, rb, target, filter, scaled_blit,
+      setup_glsl_blit_framebuffer(ctx, blit, drawFb, rb, target, filter, scaled_blit,
                                   do_depth);
    }
    else {
@@ -681,7 +684,7 @@ blitframebuffer_texture(struct gl_context *ctx,
     */
    if (ctx->Extensions.EXT_texture_sRGB_decode) {
       if (_mesa_get_format_color_encoding(rb->Format) == GL_SRGB &&
-          ctx->DrawBuffer->Visual.sRGBCapable) {
+          drawFb->Visual.sRGBCapable) {
          _mesa_SamplerParameteri(fb_tex_blit.sampler,
                                  GL_TEXTURE_SRGB_DECODE_EXT, GL_DECODE_EXT);
          _mesa_set_framebuffer_srgb(ctx, GL_TRUE);
@@ -873,6 +876,8 @@ _mesa_meta_setup_sampler(struct gl_context *ctx,
  */
 GLbitfield
 _mesa_meta_BlitFramebuffer(struct gl_context *ctx,
+                           const struct gl_framebuffer *readFb,
+                           const struct gl_framebuffer *drawFb,
                            GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
                            GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
                            GLbitfield mask, GLenum filter)
@@ -894,7 +899,7 @@ _mesa_meta_BlitFramebuffer(struct gl_context *ctx,
                                       ctx->Extensions.ARB_fragment_shader;
 
    /* Multisample texture blit support requires texture multisample. */
-   if (ctx->ReadBuffer->Visual.samples > 0 &&
+   if (readFb->Visual.samples > 0 &&
        !ctx->Extensions.ARB_texture_multisample) {
       return mask;
    }
@@ -902,7 +907,8 @@ _mesa_meta_BlitFramebuffer(struct gl_context *ctx,
    /* Clip a copy of the blit coordinates. If these differ from the input
     * coordinates, then we'll set the scissor.
     */
-   if (!_mesa_clip_blit(ctx, &clip.srcX0, &clip.srcY0, &clip.srcX1, &clip.srcY1,
+   if (!_mesa_clip_blit(ctx, readFb, drawFb,
+                        &clip.srcX0, &clip.srcY0, &clip.srcX1, &clip.srcY1,
                         &clip.dstX0, &clip.dstY0, &clip.dstX1, &clip.dstY1)) {
       /* clipped/scissored everything away */
       return 0;
@@ -930,7 +936,8 @@ _mesa_meta_BlitFramebuffer(struct gl_context *ctx,
 
    /* Try faster, direct texture approach first */
    if (mask & GL_COLOR_BUFFER_BIT) {
-      if (blitframebuffer_texture(ctx, srcX0, srcY0, srcX1, srcY1,
+      if (blitframebuffer_texture(ctx, readFb, drawFb,
+                                  srcX0, srcY0, srcX1, srcY1,
                                   dstX0, dstY0, dstX1, dstY1,
                                   filter, dstFlipX, dstFlipY,
                                   use_glsl_version, false)) {
@@ -939,7 +946,8 @@ _mesa_meta_BlitFramebuffer(struct gl_context *ctx,
    }
 
    if (mask & GL_DEPTH_BUFFER_BIT && use_glsl_version) {
-      if (blitframebuffer_texture(ctx, srcX0, srcY0, srcX1, srcY1,
+      if (blitframebuffer_texture(ctx, readFb, drawFb,
+                                  srcX0, srcY0, srcX1, srcY1,
                                   dstX0, dstY0, dstX1, dstY1,
                                   filter, dstFlipX, dstFlipY,
                                   use_glsl_version, true)) {
@@ -975,20 +983,22 @@ _mesa_meta_glsl_blit_cleanup(struct blit_state *blit)
 
 void
 _mesa_meta_and_swrast_BlitFramebuffer(struct gl_context *ctx,
+                                      struct gl_framebuffer *readFb,
+                                      struct gl_framebuffer *drawFb,
                                       GLint srcX0, GLint srcY0,
                                       GLint srcX1, GLint srcY1,
                                       GLint dstX0, GLint dstY0,
                                       GLint dstX1, GLint dstY1,
                                       GLbitfield mask, GLenum filter)
 {
-   mask = _mesa_meta_BlitFramebuffer(ctx,
+   mask = _mesa_meta_BlitFramebuffer(ctx, readFb, drawFb,
                                      srcX0, srcY0, srcX1, srcY1,
                                      dstX0, dstY0, dstX1, dstY1,
                                      mask, filter);
    if (mask == 0x0)
       return;
 
-   _swrast_BlitFramebuffer(ctx,
+   _swrast_BlitFramebuffer(ctx, readFb, drawFb,
                            srcX0, srcY0, srcX1, srcY1,
                            dstX0, dstY0, dstX1, dstY1,
                            mask, filter);
diff --git a/src/mesa/drivers/common/meta_copy_image.c b/src/mesa/drivers/common/meta_copy_image.c
index fc0cbaf1bd8..1729766f78d 100644
--- a/src/mesa/drivers/common/meta_copy_image.c
+++ b/src/mesa/drivers/common/meta_copy_image.c
@@ -189,7 +189,8 @@ _mesa_meta_CopyImageSubData_uncompressed(struct gl_context *ctx,
     * We have already created views to ensure that the texture formats
     * match.
     */
-   ctx->Driver.BlitFramebuffer(ctx, src_x, src_y,
+   ctx->Driver.BlitFramebuffer(ctx, ctx->ReadBuffer, ctx->DrawBuffer,
+                               src_x, src_y,
                                src_x + src_width, src_y + src_height,
                                dst_x, dst_y,
                                dst_x + src_width, dst_y + src_height,
diff --git a/src/mesa/drivers/common/meta_tex_subimage.c b/src/mesa/drivers/common/meta_tex_subimage.c
index 977ee5ad93e..68c8273fe4f 100644
--- a/src/mesa/drivers/common/meta_tex_subimage.c
+++ b/src/mesa/drivers/common/meta_tex_subimage.c
@@ -206,7 +206,8 @@ _mesa_meta_pbo_TexSubImage(struct gl_context *ctx, GLuint dims,
 
    _mesa_update_state(ctx);
 
-   if (_mesa_meta_BlitFramebuffer(ctx, 0, 0, width, height,
+   if (_mesa_meta_BlitFramebuffer(ctx, ctx->ReadBuffer, ctx->DrawBuffer,
+                                  0, 0, width, height,
                                   xoffset, yoffset,
                                   xoffset + width, yoffset + height,
                                   GL_COLOR_BUFFER_BIT, GL_NEAREST))
@@ -220,7 +221,8 @@ _mesa_meta_pbo_TexSubImage(struct gl_context *ctx, GLuint dims,
 
       _mesa_update_state(ctx);
 
-      _mesa_meta_BlitFramebuffer(ctx, 0, 0, width, height,
+      _mesa_meta_BlitFramebuffer(ctx, ctx->ReadBuffer, ctx->DrawBuffer,
+                                 0, 0, width, height,
                                  xoffset, yoffset,
                                  xoffset + width, yoffset + height,
                                  GL_COLOR_BUFFER_BIT, GL_NEAREST);
@@ -324,7 +326,8 @@ _mesa_meta_pbo_GetTexSubImage(struct gl_context *ctx, GLuint dims,
 
    _mesa_update_state(ctx);
 
-   if (_mesa_meta_BlitFramebuffer(ctx, xoffset, yoffset,
+   if (_mesa_meta_BlitFramebuffer(ctx, ctx->ReadBuffer, ctx->DrawBuffer,
+                                  xoffset, yoffset,
                                   xoffset + width, yoffset + height,
                                   0, 0, width, height,
                                   GL_COLOR_BUFFER_BIT, GL_NEAREST))
@@ -338,7 +341,8 @@ _mesa_meta_pbo_GetTexSubImage(struct gl_context *ctx, GLuint dims,
 
       _mesa_update_state(ctx);
 
-      _mesa_meta_BlitFramebuffer(ctx, xoffset, yoffset,
+      _mesa_meta_BlitFramebuffer(ctx, ctx->ReadBuffer, ctx->DrawBuffer,
+                                 xoffset, yoffset,
                                  xoffset + width, yoffset + height,
                                  0, 0, width, height,
                                  GL_COLOR_BUFFER_BIT, GL_NEAREST);
diff --git a/src/mesa/drivers/dri/i915/intel_fbo.c b/src/mesa/drivers/dri/i915/intel_fbo.c
index e138b854e33..ead1b17b69d 100644
--- a/src/mesa/drivers/dri/i915/intel_fbo.c
+++ b/src/mesa/drivers/dri/i915/intel_fbo.c
@@ -649,6 +649,8 @@ intel_validate_framebuffer(struct gl_context *ctx, struct gl_framebuffer *fb)
  */
 static GLbitfield
 intel_blit_framebuffer_with_blitter(struct gl_context *ctx,
+                                    const struct gl_framebuffer *readFb,
+                                    const struct gl_framebuffer *drawFb,
                                     GLint srcX0, GLint srcY0,
                                     GLint srcX1, GLint srcY1,
                                     GLint dstX0, GLint dstY0,
@@ -659,8 +661,6 @@ intel_blit_framebuffer_with_blitter(struct gl_context *ctx,
 
    if (mask & GL_COLOR_BUFFER_BIT) {
       GLint i;
-      const struct gl_framebuffer *drawFb = ctx->DrawBuffer;
-      const struct gl_framebuffer *readFb = ctx->ReadBuffer;
       struct gl_renderbuffer *src_rb = readFb->_ColorReadBuffer;
       struct intel_renderbuffer *src_irb = intel_renderbuffer(src_rb);
 
@@ -696,8 +696,8 @@ intel_blit_framebuffer_with_blitter(struct gl_context *ctx,
        * results are undefined if any destination pixels have a dependency on
        * source pixels.
        */
-      for (i = 0; i < ctx->DrawBuffer->_NumColorDrawBuffers; i++) {
-         struct gl_renderbuffer *dst_rb = ctx->DrawBuffer->_ColorDrawBuffers[i];
+      for (i = 0; i < drawFb->_NumColorDrawBuffers; i++) {
+         struct gl_renderbuffer *dst_rb = drawFb->_ColorDrawBuffers[i];
          struct intel_renderbuffer *dst_irb = intel_renderbuffer(dst_rb);
 
          if (!dst_irb) {
@@ -738,12 +738,14 @@ intel_blit_framebuffer_with_blitter(struct gl_context *ctx,
 
 static void
 intel_blit_framebuffer(struct gl_context *ctx,
+                       struct gl_framebuffer *readFb,
+                       struct gl_framebuffer *drawFb,
                        GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
                        GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
                        GLbitfield mask, GLenum filter)
 {
    /* Try using the BLT engine. */
-   mask = intel_blit_framebuffer_with_blitter(ctx,
+   mask = intel_blit_framebuffer_with_blitter(ctx, readFb, drawFb,
                                               srcX0, srcY0, srcX1, srcY1,
                                               dstX0, dstY0, dstX1, dstY1,
                                               mask, filter);
@@ -751,7 +753,7 @@ intel_blit_framebuffer(struct gl_context *ctx,
       return;
 
 
-   _mesa_meta_and_swrast_BlitFramebuffer(ctx,
+   _mesa_meta_and_swrast_BlitFramebuffer(ctx, readFb, drawFb,
                                          srcX0, srcY0, srcX1, srcY1,
                                          dstX0, dstY0, dstX1, dstY1,
                                          mask, filter);
diff --git a/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp b/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp
index 936feafdae4..10a53dc0ac4 100644
--- a/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp
+++ b/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp
@@ -125,6 +125,8 @@ do_blorp_blit(struct brw_context *brw, GLbitfield buffer_bit,
 
 static bool
 try_blorp_blit(struct brw_context *brw,
+               const struct gl_framebuffer *read_fb,
+               const struct gl_framebuffer *draw_fb,
                GLfloat srcX0, GLfloat srcY0, GLfloat srcX1, GLfloat srcY1,
                GLfloat dstX0, GLfloat dstY0, GLfloat dstX1, GLfloat dstY1,
                GLenum filter, GLbitfield buffer_bit)
@@ -136,11 +138,8 @@ try_blorp_blit(struct brw_context *brw,
     */
    intel_prepare_render(brw);
 
-   const struct gl_framebuffer *read_fb = ctx->ReadBuffer;
-   const struct gl_framebuffer *draw_fb = ctx->DrawBuffer;
-
    bool mirror_x, mirror_y;
-   if (brw_meta_mirror_clip_and_scissor(ctx,
+   if (brw_meta_mirror_clip_and_scissor(ctx, read_fb, draw_fb,
                                         &srcX0, &srcY0, &srcX1, &srcY1,
                                         &dstX0, &dstY0, &dstX1, &dstY1,
                                         &mirror_x, &mirror_y))
@@ -154,8 +153,8 @@ try_blorp_blit(struct brw_context *brw,
    switch (buffer_bit) {
    case GL_COLOR_BUFFER_BIT:
       src_irb = intel_renderbuffer(read_fb->_ColorReadBuffer);
-      for (unsigned i = 0; i < ctx->DrawBuffer->_NumColorDrawBuffers; ++i) {
-         dst_irb = intel_renderbuffer(ctx->DrawBuffer->_ColorDrawBuffers[i]);
+      for (unsigned i = 0; i < draw_fb->_NumColorDrawBuffers; ++i) {
+         dst_irb = intel_renderbuffer(draw_fb->_ColorDrawBuffers[i]);
 	 if (dst_irb)
             do_blorp_blit(brw, buffer_bit,
                           src_irb, src_irb->Base.Base.Format,
@@ -317,6 +316,8 @@ brw_blorp_copytexsubimage(struct brw_context *brw,
 
 GLbitfield
 brw_blorp_framebuffer(struct brw_context *brw,
+                      struct gl_framebuffer *readFb,
+                      struct gl_framebuffer *drawFb,
                       GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
                       GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
                       GLbitfield mask, GLenum filter)
@@ -333,7 +334,7 @@ brw_blorp_framebuffer(struct brw_context *brw,
 
    for (unsigned int i = 0; i < ARRAY_SIZE(buffer_bits); ++i) {
       if ((mask & buffer_bits[i]) &&
-       try_blorp_blit(brw,
+       try_blorp_blit(brw, readFb, drawFb,
                       srcX0, srcY0, srcX1, srcY1,
                       dstX0, dstY0, dstX1, dstY1,
                       filter, buffer_bits[i])) {
diff --git a/src/mesa/drivers/dri/i965/brw_context.h b/src/mesa/drivers/dri/i965/brw_context.h
index 6195d3d8158..d315793b0b5 100644
--- a/src/mesa/drivers/dri/i965/brw_context.h
+++ b/src/mesa/drivers/dri/i965/brw_context.h
@@ -1489,6 +1489,8 @@ void brw_meta_updownsample(struct brw_context *brw,
                            struct intel_mipmap_tree *dst);
 
 void brw_meta_fbo_stencil_blit(struct brw_context *brw,
+                               struct gl_framebuffer *read_fb,
+                               struct gl_framebuffer *draw_fb,
                                GLfloat srcX0, GLfloat srcY0,
                                GLfloat srcX1, GLfloat srcY1,
                                GLfloat dstX0, GLfloat dstY0,
@@ -1713,6 +1715,8 @@ gen7_resume_transform_feedback(struct gl_context *ctx,
 /* brw_blorp_blit.cpp */
 GLbitfield
 brw_blorp_framebuffer(struct brw_context *brw,
+                      struct gl_framebuffer *readFb,
+                      struct gl_framebuffer *drawFb,
                       GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
                       GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
                       GLbitfield mask, GLenum filter);
diff --git a/src/mesa/drivers/dri/i965/brw_meta_stencil_blit.c b/src/mesa/drivers/dri/i965/brw_meta_stencil_blit.c
index b9b481b90eb..fc7018d15b9 100644
--- a/src/mesa/drivers/dri/i965/brw_meta_stencil_blit.c
+++ b/src/mesa/drivers/dri/i965/brw_meta_stencil_blit.c
@@ -460,15 +460,17 @@ error:
 
 void
 brw_meta_fbo_stencil_blit(struct brw_context *brw,
+                          struct gl_framebuffer *read_fb,
+                          struct gl_framebuffer *draw_fb,
                           GLfloat src_x0, GLfloat src_y0,
                           GLfloat src_x1, GLfloat src_y1,
                           GLfloat dst_x0, GLfloat dst_y0,
                           GLfloat dst_x1, GLfloat dst_y1)
 {
    struct gl_context *ctx = &brw->ctx;
-   struct gl_renderbuffer *draw_fb =
-      ctx->DrawBuffer->Attachment[BUFFER_STENCIL].Renderbuffer;
-   const struct intel_renderbuffer *dst_irb = intel_renderbuffer(draw_fb);
+   struct gl_renderbuffer *draw_rb =
+      draw_fb->Attachment[BUFFER_STENCIL].Renderbuffer;
+   const struct intel_renderbuffer *dst_irb = intel_renderbuffer(draw_rb);
    struct intel_mipmap_tree *dst_mt = dst_irb->mt;
 
    if (!dst_mt)
@@ -478,7 +480,7 @@ brw_meta_fbo_stencil_blit(struct brw_context *brw,
       dst_mt = dst_mt->stencil_mt;
 
    bool mirror_x, mirror_y;
-   if (brw_meta_mirror_clip_and_scissor(ctx,
+   if (brw_meta_mirror_clip_and_scissor(ctx, read_fb, draw_fb,
                                         &src_x0, &src_y0, &src_x1, &src_y1,
                                         &dst_x0, &dst_y0, &dst_x1, &dst_y1,
                                         &mirror_x, &mirror_y))
diff --git a/src/mesa/drivers/dri/i965/brw_meta_util.c b/src/mesa/drivers/dri/i965/brw_meta_util.c
index 72ed96ce692..a3b060413e5 100644
--- a/src/mesa/drivers/dri/i965/brw_meta_util.c
+++ b/src/mesa/drivers/dri/i965/brw_meta_util.c
@@ -104,15 +104,14 @@ clip_or_scissor(bool mirror,
 
 bool
 brw_meta_mirror_clip_and_scissor(const struct gl_context *ctx,
+                                 const struct gl_framebuffer *read_fb,
+                                 const struct gl_framebuffer *draw_fb,
                                  GLfloat *srcX0, GLfloat *srcY0,
                                  GLfloat *srcX1, GLfloat *srcY1,
                                  GLfloat *dstX0, GLfloat *dstY0,
                                  GLfloat *dstX1, GLfloat *dstY1,
                                  bool *mirror_x, bool *mirror_y)
 {
-   const struct gl_framebuffer *read_fb = ctx->ReadBuffer;
-   const struct gl_framebuffer *draw_fb = ctx->DrawBuffer;
-
    *mirror_x = false;
    *mirror_y = false;
 
diff --git a/src/mesa/drivers/dri/i965/brw_meta_util.h b/src/mesa/drivers/dri/i965/brw_meta_util.h
index ccd8642010c..dc9dff2bce3 100644
--- a/src/mesa/drivers/dri/i965/brw_meta_util.h
+++ b/src/mesa/drivers/dri/i965/brw_meta_util.h
@@ -33,6 +33,8 @@ extern "C" {
 
 bool
 brw_meta_mirror_clip_and_scissor(const struct gl_context *ctx,
+                                 const struct gl_framebuffer *read_fb,
+                                 const struct gl_framebuffer *draw_fb,
                                  GLfloat *srcX0, GLfloat *srcY0,
                                  GLfloat *srcX1, GLfloat *srcY1,
                                  GLfloat *dstX0, GLfloat *dstY0,
diff --git a/src/mesa/drivers/dri/i965/intel_fbo.c b/src/mesa/drivers/dri/i965/intel_fbo.c
index 7bdf99548f6..3ee1a55b8c7 100644
--- a/src/mesa/drivers/dri/i965/intel_fbo.c
+++ b/src/mesa/drivers/dri/i965/intel_fbo.c
@@ -779,6 +779,8 @@ intel_validate_framebuffer(struct gl_context *ctx, struct gl_framebuffer *fb)
  */
 static GLbitfield
 intel_blit_framebuffer_with_blitter(struct gl_context *ctx,
+                                    const struct gl_framebuffer *readFb,
+                                    const struct gl_framebuffer *drawFb,
                                     GLint srcX0, GLint srcY0,
                                     GLint srcX1, GLint srcY1,
                                     GLint dstX0, GLint dstY0,
@@ -794,8 +796,6 @@ intel_blit_framebuffer_with_blitter(struct gl_context *ctx,
 
    if (mask & GL_COLOR_BUFFER_BIT) {
       GLint i;
-      const struct gl_framebuffer *drawFb = ctx->DrawBuffer;
-      const struct gl_framebuffer *readFb = ctx->ReadBuffer;
       struct gl_renderbuffer *src_rb = readFb->_ColorReadBuffer;
       struct intel_renderbuffer *src_irb = intel_renderbuffer(src_rb);
 
@@ -831,8 +831,8 @@ intel_blit_framebuffer_with_blitter(struct gl_context *ctx,
        * results are undefined if any destination pixels have a dependency on
        * source pixels.
        */
-      for (i = 0; i < ctx->DrawBuffer->_NumColorDrawBuffers; i++) {
-         struct gl_renderbuffer *dst_rb = ctx->DrawBuffer->_ColorDrawBuffers[i];
+      for (i = 0; i < drawFb->_NumColorDrawBuffers; i++) {
+         struct gl_renderbuffer *dst_rb = drawFb->_ColorDrawBuffers[i];
          struct intel_renderbuffer *dst_irb = intel_renderbuffer(dst_rb);
 
          if (!dst_irb) {
@@ -863,6 +863,8 @@ intel_blit_framebuffer_with_blitter(struct gl_context *ctx,
 
 static void
 intel_blit_framebuffer(struct gl_context *ctx,
+                       struct gl_framebuffer *readFb,
+                       struct gl_framebuffer *drawFb,
                        GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
                        GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
                        GLbitfield mask, GLenum filter)
@@ -876,7 +878,7 @@ intel_blit_framebuffer(struct gl_context *ctx,
    if (!_mesa_check_conditional_render(ctx))
       return;
 
-   mask = brw_blorp_framebuffer(brw,
+   mask = brw_blorp_framebuffer(brw, readFb, drawFb,
                                 srcX0, srcY0, srcX1, srcY1,
                                 dstX0, dstY0, dstX1, dstY1,
                                 mask, filter);
@@ -884,7 +886,7 @@ intel_blit_framebuffer(struct gl_context *ctx,
       return;
 
    if (brw->gen >= 8 && (mask & GL_STENCIL_BUFFER_BIT)) {
-      brw_meta_fbo_stencil_blit(brw_context(ctx),
+      brw_meta_fbo_stencil_blit(brw_context(ctx), readFb, drawFb,
                                 srcX0, srcY0, srcX1, srcY1,
                                 dstX0, dstY0, dstX1, dstY1);
       mask &= ~GL_STENCIL_BUFFER_BIT;
@@ -893,21 +895,21 @@ intel_blit_framebuffer(struct gl_context *ctx,
    }
 
    /* Try using the BLT engine. */
-   mask = intel_blit_framebuffer_with_blitter(ctx,
+   mask = intel_blit_framebuffer_with_blitter(ctx, readFb, drawFb,
                                               srcX0, srcY0, srcX1, srcY1,
                                               dstX0, dstY0, dstX1, dstY1,
                                               mask, filter);
    if (mask == 0x0)
       return;
 
-   mask = _mesa_meta_BlitFramebuffer(ctx,
+   mask = _mesa_meta_BlitFramebuffer(ctx, readFb, drawFb,
                                      srcX0, srcY0, srcX1, srcY1,
                                      dstX0, dstY0, dstX1, dstY1,
                                      mask, filter);
    if (mask == 0x0)
       return;
 
-   _swrast_BlitFramebuffer(ctx,
+   _swrast_BlitFramebuffer(ctx, readFb, drawFb,
                            srcX0, srcY0, srcX1, srcY1,
                            dstX0, dstY0, dstX1, dstY1,
                            mask, filter);
diff --git a/src/mesa/main/blit.c b/src/mesa/main/blit.c
index 0b70a3da43f..b97b564793c 100644
--- a/src/mesa/main/blit.c
+++ b/src/mesa/main/blit.c
@@ -506,7 +506,7 @@ _mesa_BlitFramebuffer(GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
    }
 
    ASSERT(ctx->Driver.BlitFramebuffer);
-   ctx->Driver.BlitFramebuffer(ctx,
+   ctx->Driver.BlitFramebuffer(ctx, ctx->ReadBuffer, ctx->DrawBuffer,
                                srcX0, srcY0, srcX1, srcY1,
                                dstX0, dstY0, dstX1, dstY1,
                                mask, filter);
diff --git a/src/mesa/main/dd.h b/src/mesa/main/dd.h
index 6883e1808f9..40f68b4a7fd 100644
--- a/src/mesa/main/dd.h
+++ b/src/mesa/main/dd.h
@@ -713,6 +713,8 @@ struct dd_function_table {
                                struct gl_framebuffer *fb);
    /*@}*/
    void (*BlitFramebuffer)(struct gl_context *ctx,
+                           struct gl_framebuffer *readFb,
+                           struct gl_framebuffer *drawFb,
                            GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
                            GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
                            GLbitfield mask, GLenum filter);
diff --git a/src/mesa/main/image.c b/src/mesa/main/image.c
index 9ad97c56e40..c37900cf954 100644
--- a/src/mesa/main/image.c
+++ b/src/mesa/main/image.c
@@ -861,19 +861,21 @@ clip_left_or_bottom(GLint *srcX0, GLint *srcX1,
  */
 GLboolean
 _mesa_clip_blit(struct gl_context *ctx,
+                const struct gl_framebuffer *readFb,
+                const struct gl_framebuffer *drawFb,
                 GLint *srcX0, GLint *srcY0, GLint *srcX1, GLint *srcY1,
                 GLint *dstX0, GLint *dstY0, GLint *dstX1, GLint *dstY1)
 {
    const GLint srcXmin = 0;
-   const GLint srcXmax = ctx->ReadBuffer->Width;
+   const GLint srcXmax = readFb->Width;
    const GLint srcYmin = 0;
-   const GLint srcYmax = ctx->ReadBuffer->Height;
+   const GLint srcYmax = readFb->Height;
 
    /* these include scissor bounds */
-   const GLint dstXmin = ctx->DrawBuffer->_Xmin;
-   const GLint dstXmax = ctx->DrawBuffer->_Xmax;
-   const GLint dstYmin = ctx->DrawBuffer->_Ymin;
-   const GLint dstYmax = ctx->DrawBuffer->_Ymax;
+   const GLint dstXmin = drawFb->_Xmin;
+   const GLint dstXmax = drawFb->_Xmax;
+   const GLint dstYmin = drawFb->_Ymin;
+   const GLint dstYmax = drawFb->_Ymax;
 
    /*
    printf("PreClipX:  src: %d .. %d  dst: %d .. %d\n",
diff --git a/src/mesa/main/image.h b/src/mesa/main/image.h
index 44863cc5927..501586bfbd3 100644
--- a/src/mesa/main/image.h
+++ b/src/mesa/main/image.h
@@ -32,6 +32,7 @@
 
 struct gl_context;
 struct gl_pixelstore_attrib;
+struct gl_framebuffer;
 
 extern void
 _mesa_swap2_copy(GLushort *dst, GLushort *src, GLuint n);
@@ -140,6 +141,8 @@ _mesa_clip_to_region(GLint xmin, GLint ymin,
 
 extern GLboolean
 _mesa_clip_blit(struct gl_context *ctx,
+                const struct gl_framebuffer *readFb,
+                const struct gl_framebuffer *drawFb,
                 GLint *srcX0, GLint *srcY0, GLint *srcX1, GLint *srcY1,
                 GLint *dstX0, GLint *dstY0, GLint *dstX1, GLint *dstY1);
 
diff --git a/src/mesa/state_tracker/st_cb_blit.c b/src/mesa/state_tracker/st_cb_blit.c
index 9c33f4eb99c..bbaedd108f6 100644
--- a/src/mesa/state_tracker/st_cb_blit.c
+++ b/src/mesa/state_tracker/st_cb_blit.c
@@ -73,6 +73,8 @@ st_adjust_blit_for_msaa_resolve(struct pipe_blit_info *blit)
 
 static void
 st_BlitFramebuffer(struct gl_context *ctx,
+                   struct gl_framebuffer *readFB,
+                   struct gl_framebuffer *drawFB,
                    GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
                    GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
                    GLbitfield mask, GLenum filter)
@@ -83,8 +85,6 @@ st_BlitFramebuffer(struct gl_context *ctx,
    const uint pFilter = ((filter == GL_NEAREST)
                          ? PIPE_TEX_FILTER_NEAREST
                          : PIPE_TEX_FILTER_LINEAR);
-   struct gl_framebuffer *readFB = ctx->ReadBuffer;
-   struct gl_framebuffer *drawFB = ctx->DrawBuffer;
    struct {
       GLint srcX0, srcY0, srcX1, srcY1;
       GLint dstX0, dstY0, dstX1, dstY1;
@@ -108,7 +108,7 @@ st_BlitFramebuffer(struct gl_context *ctx,
     *
     * XXX: This should depend on mask !
     */
-   if (!_mesa_clip_blit(ctx,
+   if (!_mesa_clip_blit(ctx, readFB, drawFB,
                         &clip.srcX0, &clip.srcY0, &clip.srcX1, &clip.srcY1,
                         &clip.dstX0, &clip.dstY0, &clip.dstX1, &clip.dstY1)) {
       return; /* nothing to draw/blit */
diff --git a/src/mesa/swrast/s_blit.c b/src/mesa/swrast/s_blit.c
index e3b45f14682..48936d32917 100644
--- a/src/mesa/swrast/s_blit.c
+++ b/src/mesa/swrast/s_blit.c
@@ -107,14 +107,14 @@ RESAMPLE(resample_row_16, GLuint, 4)
  */
 static void
 blit_nearest(struct gl_context *ctx,
+             struct gl_framebuffer *readFb,
+             struct gl_framebuffer *drawFb,
              GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
              GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
              GLbitfield buffer)
 {
    struct gl_renderbuffer *readRb, *drawRb = NULL;
    struct gl_renderbuffer_attachment *readAtt = NULL, *drawAtt = NULL;
-   struct gl_framebuffer *readFb = ctx->ReadBuffer;
-   struct gl_framebuffer *drawFb = ctx->DrawBuffer;
    GLuint numDrawBuffers = 0;
    GLuint i;
 
@@ -508,11 +508,11 @@ resample_linear_row_float(GLint srcWidth, GLint dstWidth,
  */
 static void
 blit_linear(struct gl_context *ctx,
+            struct gl_framebuffer *readFb,
+            struct gl_framebuffer *drawFb,
             GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
             GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1)
 {
-   struct gl_framebuffer *drawFb = ctx->DrawBuffer;
-   struct gl_framebuffer *readFb = ctx->ReadBuffer;
    struct gl_renderbuffer *readRb = readFb->_ColorReadBuffer;
    struct gl_renderbuffer_attachment *readAtt =
       &readFb->Attachment[readFb->_ColorReadBufferIndex];
@@ -733,6 +733,8 @@ fail_no_memory:
  */
 void
 _swrast_BlitFramebuffer(struct gl_context *ctx,
+                        struct gl_framebuffer *readFb,
+                        struct gl_framebuffer *drawFb,
                         GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
                         GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
                         GLbitfield mask, GLenum filter)
@@ -756,7 +758,7 @@ _swrast_BlitFramebuffer(struct gl_context *ctx,
    if (!_mesa_check_conditional_render(ctx))
       return; /* Do not blit */
 
-   if (!_mesa_clip_blit(ctx, &srcX0, &srcY0, &srcX1, &srcY1,
+   if (!_mesa_clip_blit(ctx, readFb, drawFb, &srcX0, &srcY0, &srcX1, &srcY1,
                         &dstX0, &dstY0, &dstX1, &dstY1)) {
       return;
    }
@@ -775,14 +777,15 @@ _swrast_BlitFramebuffer(struct gl_context *ctx,
        dstY0 < dstY1) {
       for (i = 0; i < 3; i++) {
          if (mask & buffers[i]) {
-	    if (swrast_fast_copy_pixels(ctx,
-					srcX0, srcY0,
-					srcX1 - srcX0, srcY1 - srcY0,
-					dstX0, dstY0,
-					buffer_enums[i])) {
-	       mask &= ~buffers[i];
-	    }
-	 }
+            if (swrast_fast_copy_pixels(ctx,
+                                        readFb, drawFb,
+                                        srcX0, srcY0,
+                                        srcX1 - srcX0, srcY1 - srcY0,
+                                        dstX0, dstY0,
+                                        buffer_enums[i])) {
+               mask &= ~buffers[i];
+            }
+         }
       }
 
       if (!mask)
@@ -791,17 +794,17 @@ _swrast_BlitFramebuffer(struct gl_context *ctx,
 
    if (filter == GL_NEAREST) {
       for (i = 0; i < 3; i++) {
-	 if (mask & buffers[i]) {
-	    blit_nearest(ctx,  srcX0, srcY0, srcX1, srcY1,
-			 dstX0, dstY0, dstX1, dstY1, buffers[i]);
-	 }
+          if (mask & buffers[i]) {
+             blit_nearest(ctx, readFb, drawFb, srcX0, srcY0, srcX1, srcY1,
+                          dstX0, dstY0, dstX1, dstY1, buffers[i]);
+          }
       }
    }
    else {
       ASSERT(filter == GL_LINEAR);
       if (mask & GL_COLOR_BUFFER_BIT) {  /* depth/stencil not allowed */
-	 blit_linear(ctx,  srcX0, srcY0, srcX1, srcY1,
-		     dstX0, dstY0, dstX1, dstY1);
+         blit_linear(ctx, readFb, drawFb, srcX0, srcY0, srcX1, srcY1,
+                     dstX0, dstY0, dstX1, dstY1);
       }
    }
 
diff --git a/src/mesa/swrast/s_copypix.c b/src/mesa/swrast/s_copypix.c
index d001734766c..eeea20e8671 100644
--- a/src/mesa/swrast/s_copypix.c
+++ b/src/mesa/swrast/s_copypix.c
@@ -442,11 +442,11 @@ end:
  */
 GLboolean
 swrast_fast_copy_pixels(struct gl_context *ctx,
-			GLint srcX, GLint srcY, GLsizei width, GLsizei height,
-			GLint dstX, GLint dstY, GLenum type)
+                        struct gl_framebuffer *srcFb,
+                        struct gl_framebuffer *dstFb,
+                        GLint srcX, GLint srcY, GLsizei width, GLsizei height,
+                        GLint dstX, GLint dstY, GLenum type)
 {
-   struct gl_framebuffer *srcFb = ctx->ReadBuffer;
-   struct gl_framebuffer *dstFb = ctx->DrawBuffer;
    struct gl_renderbuffer *srcRb, *dstRb;
    GLint row;
    GLuint pixelBytes, widthInBytes;
@@ -637,8 +637,9 @@ _swrast_CopyPixels( struct gl_context *ctx,
 	 ctx->Pixel.ZoomX != 1.0F ||
 	 ctx->Pixel.ZoomY != 1.0F ||
 	 ctx->_ImageTransferState) &&
-       swrast_fast_copy_pixels(ctx, srcx, srcy, width, height, destx, desty,
-			       type)) {
+      swrast_fast_copy_pixels(ctx, ctx->ReadBuffer, ctx->DrawBuffer,
+                              srcx, srcy, width, height, destx, desty,
+                              type)) {
       /* all done */
       return;
    }
diff --git a/src/mesa/swrast/swrast.h b/src/mesa/swrast/swrast.h
index ac3dbe3041e..8847bced0cf 100644
--- a/src/mesa/swrast/swrast.h
+++ b/src/mesa/swrast/swrast.h
@@ -140,8 +140,10 @@ _swrast_CopyPixels( struct gl_context *ctx,
 
 extern GLboolean
 swrast_fast_copy_pixels(struct gl_context *ctx,
-			GLint srcX, GLint srcY, GLsizei width, GLsizei height,
-			GLint dstX, GLint dstY, GLenum type);
+                        struct gl_framebuffer *srcFb,
+                        struct gl_framebuffer *dstFb,
+                        GLint srcX, GLint srcY, GLsizei width, GLsizei height,
+                        GLint dstX, GLint dstY, GLenum type);
 
 extern void
 _swrast_DrawPixels( struct gl_context *ctx,
@@ -153,6 +155,8 @@ _swrast_DrawPixels( struct gl_context *ctx,
 
 extern void
 _swrast_BlitFramebuffer(struct gl_context *ctx,
+                        struct gl_framebuffer *readFb,
+                        struct gl_framebuffer *drawFb,
                         GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
                         GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
                         GLbitfield mask, GLenum filter);