mesa: allow buffers to be mapped multiple times

OpenGL allows a buffer to be mapped only once, but we also map buffers
internally, e.g. in the software primitive restart fallback, for PBOs,
vbo_get_minmax_index, etc. This has always been a problem, but it will
be a bigger problem with persistent buffer mappings, which will prevent
all Mesa functions from mapping buffers for internal purposes.

This adds a driver interface to core Mesa which supports multiple buffer
mappings and allows 2 mappings: one for the GL user and one for Mesa.

Note that Gallium supports an unlimited number of buffer and texture
mappings, so it's not really an issue for Gallium.

v2: fix unmapping in xm_dd.c, remove the GL errors there
v3: fix the intel driver (by Fredrik)

Reviewed-by: Fredrik Höglund <[email protected]>

1 files changed, 16 insertions, 12 deletions

diff --git a/src/mesa/vbo/vbo_split_copy.c b/src/mesa/vbo/vbo_split_copy.c
index 4332ef2e6d7..719ad651a89 100644
--- a/src/mesa/vbo/vbo_split_copy.c
+++ b/src/mesa/vbo/vbo_split_copy.c
@@ -451,11 +451,14 @@ replay_init( struct copy_context *copy )
 	 copy->varying[j].size = attr_size(copy->array[i]);
 	 copy->vertex_size += attr_size(copy->array[i]);
       
-	 if (_mesa_is_bufferobj(vbo) && !_mesa_bufferobj_mapped(vbo)) 
-	    ctx->Driver.MapBufferRange(ctx, 0, vbo->Size, GL_MAP_READ_BIT, vbo);
+	 if (_mesa_is_bufferobj(vbo) &&
+             !_mesa_bufferobj_mapped(vbo, MAP_INTERNAL))
+	    ctx->Driver.MapBufferRange(ctx, 0, vbo->Size, GL_MAP_READ_BIT, vbo,
+                                       MAP_INTERNAL);
 
-	 copy->varying[j].src_ptr = ADD_POINTERS(vbo->Pointer,
-						 copy->array[i]->Ptr);
+	 copy->varying[j].src_ptr =
+               ADD_POINTERS(vbo->Mappings[MAP_INTERNAL].Pointer,
+                            copy->array[i]->Ptr);
 
 	 copy->dstarray_ptr[i] = &copy->varying[j].dstarray;
       }
@@ -466,12 +469,13 @@ replay_init( struct copy_context *copy )
     * do it internally.
     */
    if (_mesa_is_bufferobj(copy->ib->obj) &&
-       !_mesa_bufferobj_mapped(copy->ib->obj)) 
+       !_mesa_bufferobj_mapped(copy->ib->obj, MAP_INTERNAL))
       ctx->Driver.MapBufferRange(ctx, 0, copy->ib->obj->Size, GL_MAP_READ_BIT,
-				 copy->ib->obj);
+				 copy->ib->obj, MAP_INTERNAL);
 
-   srcptr = (const GLubyte *) ADD_POINTERS(copy->ib->obj->Pointer,
-                                           copy->ib->ptr);
+   srcptr = (const GLubyte *)
+            ADD_POINTERS(copy->ib->obj->Mappings[MAP_INTERNAL].Pointer,
+                         copy->ib->ptr);
 
    switch (copy->ib->type) {
    case GL_UNSIGNED_BYTE:
@@ -572,15 +576,15 @@ replay_finish( struct copy_context *copy )
     */
    for (i = 0; i < copy->nr_varying; i++) {
       struct gl_buffer_object *vbo = copy->varying[i].array->BufferObj;
-      if (_mesa_is_bufferobj(vbo) && _mesa_bufferobj_mapped(vbo)) 
-	 ctx->Driver.UnmapBuffer(ctx, vbo);
+      if (_mesa_is_bufferobj(vbo) && _mesa_bufferobj_mapped(vbo, MAP_INTERNAL))
+	 ctx->Driver.UnmapBuffer(ctx, vbo, MAP_INTERNAL);
    }
 
    /* Unmap index buffer:
     */
    if (_mesa_is_bufferobj(copy->ib->obj) &&
-       _mesa_bufferobj_mapped(copy->ib->obj)) {
-      ctx->Driver.UnmapBuffer(ctx, copy->ib->obj);
+       _mesa_bufferobj_mapped(copy->ib->obj, MAP_INTERNAL)) {
+      ctx->Driver.UnmapBuffer(ctx, copy->ib->obj, MAP_INTERNAL);
    }
 }