CephFS Kernel Client response on Ceph side

Hello Ceph Devs, I looked into the CephFS kernel client and now I am confused about what happens on the cluster side when the client sends its requests. In particular I am interested in finding out what code is called then. For the longest time I though that the clients commands like read(), write() on the client side etc get mapped to the functions ceph_read(), ceph_write() in the libcephfs.cc file. But now I think that the kernel client and libcephfs.cc are two completely disjunct from one another correct? And is there any relation between the kernel client and the client found in src/client/client.cc ? Greetings