nv50: slightly less skeletal texture funcs, prevents fun segfaults

src/gallium/drivers/nv50/nv50_miptree.c

@@ -1,29 +1,83 @@
 #include "pipe/p_state.h"
 #include "pipe/p_defines.h"
 #include "pipe/p_util.h"
-#include "pipe/p_screen.h"
+#include "pipe/p_inlines.h"
 
 #include "nv50_context.h"
 
+struct nv50_miptree {
+	struct pipe_texture base;
+	struct pipe_buffer *buffer;
+};
+
+static INLINE struct nv50_miptree *
+nv50_miptree(struct pipe_texture *pt)
+{
+	return (struct nv50_miptree *)pt;
+}
+
 static struct pipe_texture *
 nv50_miptree_create(struct pipe_screen *pscreen, const struct pipe_texture *pt)
 {
+	struct pipe_winsys *ws = pscreen->winsys;
+	struct nv50_miptree *mt = CALLOC_STRUCT(nv50_miptree);
+	
 	NOUVEAU_ERR("unimplemented\n");
-	return NULL;
+
+	mt->base = *pt;
+	mt->base.refcount = 1;
+	mt->base.screen = pscreen;
+
+	mt->buffer = ws->buffer_create(ws, 256, PIPE_BUFFER_USAGE_PIXEL,
+				       512*32*4);
+	if (!mt->buffer) {
+		FREE(mt);
+		return NULL;
+	}
+
+	return &mt->base;
 }
 
 static void
-nv50_miptree_release(struct pipe_screen *pscreen, struct pipe_texture **pt)
+nv50_miptree_release(struct pipe_screen *pscreen, struct pipe_texture **ppt)
 {
+	struct pipe_winsys *ws = pscreen->winsys;
+	struct pipe_texture *pt = *ppt;
+
 	NOUVEAU_ERR("unimplemented\n");
+
+	*ppt = NULL;
+	if (--pt->refcount <= 0) {
+		struct nv50_miptree *mt = nv50_miptree(pt);
+
+		pipe_buffer_reference(ws, &mt->buffer, NULL);
+		FREE(mt);
+	}
 }
 
 static struct pipe_surface *
 nv50_miptree_surface(struct pipe_screen *pscreen, struct pipe_texture *pt,
 		     unsigned face, unsigned level, unsigned zslice)
 {
+	struct pipe_winsys *ws = pscreen->winsys;
+	struct nv50_miptree *mt = nv50_miptree(pt);
+	struct pipe_surface *ps;
+
 	NOUVEAU_ERR("unimplemented\n");
-	return NULL;
+
+	ps = ws->surface_alloc(ws);
+	if (!ps)
+		return NULL;
+
+	pipe_buffer_reference(ws, &ps->buffer, mt->buffer);
+	ps->format = pt->format;
+	ps->cpp = pt->cpp;
+	ps->width = pt->width[level];
+	ps->height = pt->height[level];
+	ps->pitch = ps->width;
+	ps->offset = 0;
+
+	return ps;
 }
 
 void