Ok -

So had this car for 6 months - everything fine.
Now all of a sudden - lots of white smoke coming from exhaust after car has warmed up. It is burning oil (was low had to add a quart).
It is running fine - no loss of power or anything strange noises.
Some threads have mentioned PCV blockage ; but, no smoke coming from dipstick.
What are some things I can get in and look at. (my first volvo - so not too familiar with specific locations of parts).

my mechanic friend says it is prolly a stuck valve?
I was thinking (more like reading) it is the turbo. If so, does it need to be replaced? or are there certain parts of the turbo that I can look at and replace?

Thanks for your time