Gerrit is useful but it's only for git. I want to setup something like it, but for subversion. Is there any software doing this job?
For which part: code review or hosting or both?
For code reviews, Review Board works well. It's not perfect, but I've used it to great success on a couple of projects. It doesn't deal at all with hosting or access controls though.
For hosting, you might try usvn, SVNManager, or svn-access-manager. I've not really used any of these tools, so I can't really comment on their usefulness.