On Fri, Sep 23, 2022 at 02:15:04PM +0800, ZiyangZhang wrote: > START_USER_RECOVERY and END_USER_RECOVERY are two new control commands > to support user recovery feature. > > After a crash, user should send START_USER_RECOVERY, it will: > (1) check if (a)current ublk_device is UBLK_S_DEV_QUIESCED which was > set by quiesce_work and (b)chardev is released > (2) reinit all ubqs, including: > (a) put the task_struct and reset ->ubq_daemon to NULL. > (b) reset all ublk_io. > (3) reset ub->mm to NULL. > > Then, user should start a new process and send FETCH_REQ on each > ubq_daemon. > > Finally, user should send END_USER_RECOVERY, it will: > (1) wait for all new ubq_daemons getting ready. > (2) update ublksrv_pid > (3) unquiesce the request queue and expect incoming ublk_queue_rq() > (4) convert ub's state to UBLK_S_DEV_LIVE > > Note: we can handle STOP_DEV between START_USER_RECOVERY and > END_USER_RECOVERY. This is helpful to users who cannot start new process > after sending START_USER_RECOVERY ctrl-cmd. > > Signed-off-by: ZiyangZhang <ZiyangZhang@xxxxxxxxxxxxxxxxx> Reviewed-by: Ming Lei <ming.lei@xxxxxxxxxx> Thanks, Ming
