most of the mining of bitcoin is done in china now, there are huge farm setup just for that.
so if the ban was real, what would that mean for mining bitcoin in general ?
If the mining is also forbidden, the miners will be shifted overseas. That is not a problem.
Some Chinese miners have already pre-emptively opened overseas operations. See
https://www.cryptocoinsnews.com/chinese-bitcoin-mining-firm-canaan-to-open-10-mw-facility-at-node-pole-sweden/China-based Canaan Creative, a bitcoin mining firm commonly known by Avalon, its bitcoin mining chip brand, will open a data center powered by hydroelectric power at the Node Pole. Owned by power companies, the technology infrastructure hub is situated in the Boden region near the Arctic Circle n in Sweden.
Canaan, which manufacturers ASIC microprocessors, claims to be the first Chinese bitcoin company to open a data center in Europe. The facility will operate at 10 MW at its initial stage, leaving room for expansion in the future.
I expect if China bans mining, these businesses will just open operations in other parts of the world, they have the cash to do it.