Accoding to the latest policy, you can spply a longer L visa if you have a Chinese wife or relatives who as permanent resident/longer stay on work visa in China. You can extend your current visa in local Entry-Exit department China.

thx for the reply

but my current visa is a resident permit for the purpose of studying. i got that visa in beijing. my school got it for me. now im with my wife in yunnan, and im not going to study for at least a year. so i have to change my visa to an L visa. ive been told i have to leave the country for that...

That's right, you need to leave China and apply for an L visa to enter China. Then you can extend your visa or apply for a longer resident permit with your marriage certificate.