Toro, B&S 190cc, White Smoke and oil coming out of the exhaust

ok, so i go out side this evening to cut the grass, i have a Toro Recycler self propelled with a Briggs & Stratton 190cc engine. I started the mower and as soon as i did i noticed white smoke coming out of the front exhaust, thought nothing of it, then within 15 seconds and about 20 feet of cutting i was engulfed with a lot of white smoke, so i stopped the mower and noticed oil on the top of the cutting deck just below the exhaust. So i stopped and put it up for the night to come in and research what is going on. Any ideas out there? Thanks