The drm_file->is_master field is redundant as it's equivalent to:
drm_file->master && drm_file->master == drm_file->minor->master
1) "=>"
Whenever we set drm_file->is_master, we also set:
drm_file->minor->master = drm_file->master;
Whenever we clear drm_file->is_master, we also call:
drm_master_put(&drm_file->minor->master);
which implicitly clears it to NULL.
2) "<="
minor->master cannot be set if it is non-NULL. Therefore, it stays as
is unless a file drops it.
If minor->master is NULL, it is only set by places that also adjust
drm_file->is_master.
Therefore, we can safely drop is_master and replace it by an inline helper
that matches:
drm_file->master && drm_file->master == drm_file->minor->master
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>