drm/vmwgfx: Cleanup the vmw bo usage in the cursor paths

Base mapped count is useless because the ttm unmap functions handle
null maps just fine so completely remove all the code related to it.
Signed-off-by: Zack Rusin <zackr@vmware.com>
Reviewed-by: Martin Krastev <krastevm@vmware.com>
Reviewed-by: Maaz Mombasawala <mombasawalam@vmware.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230131033542.953249-6-zack@kde.org

drivers/gpu/drm/vmwgfx/vmwgfx_bo.h

@@ -44,7 +44,6 @@ struct vmw_resource;
  * struct vmw_bo - TTM buffer object with vmwgfx additions
  * @base: The TTM buffer object
  * @res_tree: RB tree of resources using this buffer object as a backing MOB
- * @base_mapped_count: ttm BO mapping count; used by KMS atomic helpers.
  * @cpu_writers: Number of synccpu write grabs. Protected by reservation when
  * increased. May be decreased without reservation.
  * @dx_query_ctx: DX context if this buffer object is used as a DX query MOB
@@ -55,8 +54,6 @@ struct vmw_resource;
 struct vmw_bo {
 	struct ttm_buffer_object base;
 	struct rb_root res_tree;
-	/* For KMS atomic helpers: ttm bo mapping count */
-	atomic_t base_mapped_count;
 
 	atomic_t cpu_writers;
 	/* Not ref-counted.  Protected by binding_mutex */

drivers/gpu/drm/vmwgfx/vmwgfx_kms.c

@@ -669,7 +669,6 @@ vmw_du_cursor_plane_cleanup_fb(struct drm_plane *plane,
 		const int ret = ttm_bo_reserve(&vps->bo->base, true, false, NULL);
 
 		if (likely(ret == 0)) {
-			if (atomic_read(&vps->bo->base_mapped_count) == 0)
 			ttm_bo_kunmap(&vps->bo->map);
 			ttm_bo_unreserve(&vps->bo->base);
 		}
@@ -744,9 +743,6 @@ vmw_du_cursor_plane_prepare_fb(struct drm_plane *plane,
 
 		ret = ttm_bo_kmap(&vps->bo->base, 0, PFN_UP(size), &vps->bo->map);
 
-		if (likely(ret == 0))
-			atomic_inc(&vps->bo->base_mapped_count);
-
 		ttm_bo_unreserve(&vps->bo->base);
 
 		if (unlikely(ret != 0))
@@ -786,7 +782,6 @@ vmw_du_cursor_plane_atomic_update(struct drm_plane *plane,
 	struct vmw_plane_state *vps = vmw_plane_state_to_vps(new_state);
 	struct vmw_plane_state *old_vps = vmw_plane_state_to_vps(old_state);
 	s32 hotspot_x, hotspot_y;
-	bool dummy;
 
 	hotspot_x = du->hotspot_x;
 	hotspot_y = du->hotspot_y;
@@ -828,11 +823,6 @@ vmw_du_cursor_plane_atomic_update(struct drm_plane *plane,
 						hotspot_x, hotspot_y);
 	}
 
-	if (vps->bo) {
-		if (ttm_kmap_obj_virtual(&vps->bo->map, &dummy))
-			atomic_dec(&vps->bo->base_mapped_count);
-	}
-
 	du->cursor_x = new_state->crtc_x + du->set_gui_x;
 	du->cursor_y = new_state->crtc_y + du->set_gui_y;