I am Nigerian, requirements for business M visa to PRC

Hello good evening
I am a Nigerian and holding Nigeria passport. I want to know what are the requirements to get business M type to Shanghai China. I am holding a Social Pass here in Malaysia. and please I want to know how long it will take for the application process because I have limited time to go to PRC and conduct my business and then back to Nigeria. I have all supporting documents concerning my trade. Thank you so much waiting for your reply.