On Wed, Aug 31, 2022 at 11:51:33PM +0800, ZiyangZhang wrote: > Define some macros for recovery feature. Especially define a new state: > UBLK_S_DEV_RECOVERING which implies the ublk_device is recovering. > > UBLK_F_USER_RECOVERY implies that: > (1) ublk_drv enables recovery feature. It won't let monitor_work to > automatically abort rqs and release the device. Instead, it waits > for user's START_USER_RECOVERY ctrl-cmd. > > (2) In monitor_work after a crash, ublk_drv ends(aborts) rqs issued to > userspace(ublksrv) before crash. > > (3) In task work and ublk_queue_rq() after a crash, ublk_drv requeues > rqs dispatched after crash. > > UBLK_F_USER_RECOVERY_REISSUE implies that: > (1) everything UBLK_F_USER_RECOVERY implies except > (2) ublk_drv requeues rqs issued to userspace(ublksrv) before crash. > > UBLK_F_USER_RECOVERY_REISSUE is designed for backends which: > (1) tolerate double-writes because we may issue the same rq twice. > (2) cannot let frontend users get I/O error, such as a RDONLY system. > > Signed-off-by: ZiyangZhang <ZiyangZhang@xxxxxxxxxxxxxxxxx> > --- > drivers/block/ublk_drv.c | 31 ++++++++++++++++++++++++++++++- > include/uapi/linux/ublk_cmd.h | 7 +++++++ > 2 files changed, 37 insertions(+), 1 deletion(-) > > diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c > index 0c6db0978ed0..0c3d32e8d686 100644 > --- a/drivers/block/ublk_drv.c > +++ b/drivers/block/ublk_drv.c > @@ -49,7 +49,9 @@ > /* All UBLK_F_* have to be included into UBLK_F_ALL */ > #define UBLK_F_ALL (UBLK_F_SUPPORT_ZERO_COPY \ > | UBLK_F_URING_CMD_COMP_IN_TASK \ > - | UBLK_F_NEED_GET_DATA) > + | UBLK_F_NEED_GET_DATA \ > + | UBLK_F_USER_RECOVERY \ > + | UBLK_F_USER_RECOVERY_REISSUE) > > /* All UBLK_PARAM_TYPE_* should be included here */ > #define UBLK_PARAM_TYPE_ALL (UBLK_PARAM_TYPE_BASIC | UBLK_PARAM_TYPE_DISCARD) > @@ -323,6 +325,33 @@ static inline int ublk_queue_cmd_buf_size(struct ublk_device *ub, int q_id) > PAGE_SIZE); > } > > +/* > + * TODO: UBLK_F_USER_RECOVERY should be a flag for device, not for queue, > + * since "some queues are aborted while others are recoverd" is really weird. > + */ > +static inline bool ublk_can_use_recovery(struct ublk_device *ub) > +{ > + struct ublk_queue *ubq = ublk_get_queue(ub, 0); This way is too tricky, just wondering why you don't passe ubq to ublk_can_use_recovery()? Thanks, Ming