Got hacked- lost ranking what's next?

Basically I got hacked two weeks ago, the malware created hundreds of thousands of spamy pages, all were indexed by Google. The site map was inaccessible, lost all the rankings. Steps I've done so far: 1. Cleaned the site 2. Created and resubmitted a site map

Question, What can I do next? Will I ever get the rankings back? The website had around 30k organic visitors monthly.