Loan and profit

if i loan R20 000 to a person to do a business deal and ask for R22 000 in return where the extra R2000 is considered to be my share of the profit
what is the correct procedure to make the transaction halaal?
if it is riba ,then under what circumstances am i allowed to make a profit eg.( must the loan be only for a transaction. must it be stipulated that the extra is my share of the profit etc? )