Merge PR #18096 into master

Merge PR #18096 into master

* refs/pull/18096/head:
	os/bluestore: factor VDO into bluestore's 'allocated' value
	os/filestore: estimate omap_allocated
	os/ObjectMap: add get_db() accessor
	osd/OSDMap: include data, omap in 'osd df' output
	os/bluestore: report omap and internal metadata usage
	os/bluestore/BlueFS: drop get_fs_usage(); add get_used()
	kv: add per-prefix space estimation
	osd: decouple statfs update from hb peers, pg count
	osd: drop useless OSDService::update_osd_stat()
	osd/osd_types: separate accounting for data, omap, and metadata
	osd: re-add get_num_pgs()

Reviewed-by: Igor Fedotov <ifedotov@suse.com>