nfsd_vfs_write
status = nfsd_vfs_write(rqstp, &cstate->current_fh, nf,
err = nfsd_vfs_write(rqstp, fhp, nf, offset, payload, cnt,
__be32 nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp,