[NFS-Ganesha-Devel] Correct usage of nfs3_read_cb callback?

I'm implementing a new FSAL. At the end of a successful read2() function, I call the callback as follows: void myfsal_read2(struct fsal_obj_handle *obj_hdl, bool bypass, fsal_async_cb done_cb, struct fsal_io_arg *read_arg, void *caller_arg){ // ... read data ... fsal_status_t status = fsalstat(ERR_FSAL_NO_ERROR, 0); done_cb(obj_hdl, status, read_arg, caller_arg); } This generates the following error in src/Protocols/NFS/nfs_proto_tools.c, line 213: nfs_RetryableError :NFS3 :CRIT :Possible implementation error: ERR_FSAL_NO_ERROR managed as an error From the client side, read / write operations work as expected. If I don't call the callback function, the NFS operation doesn't complete. What are the correct usage of the callback functions, after successful operations? Thanks, Bjorn