linux/include/uapi
ZiyangZhang c732a852b4 ublk_drv: add START_USER_RECOVERY and END_USER_RECOVERY support
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@linux.alibaba.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20220923153919.44078-7-ZiyangZhang@linux.alibaba.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-23 19:09:56 -06:00
..
asm-generic TTY / Serial driver changes for 6.0-rc1 2022-08-08 11:31:40 -07:00
drm drm for 5.20/6.0 2022-08-03 19:52:08 -07:00
linux ublk_drv: add START_USER_RECOVERY and END_USER_RECOVERY support 2022-09-23 19:09:56 -06:00
misc habanalabs: add status of reset after device release 2022-07-12 09:09:31 +03:00
mtd mtdchar: prevent integer overflow in a safety check 2022-06-09 15:03:32 +02:00
rdma v5.20 pull request 2022-08-04 19:54:32 -07:00
scsi treewide: uapi: Replace zero-length arrays with flexible-array members 2022-06-28 21:26:05 +02:00
sound sound updates for 6.0-rc1 2022-08-06 10:19:51 -07:00
video
xen Improve docs for IOCTL_GNTDEV_MAP_GRANT_REF 2022-02-03 08:23:32 +01:00
Kbuild