On Wed, Oct 02, 2024 at 04:09:48PM -0600, Uday Shankar wrote: > ublk currently supports the following behaviors on ublk server exit: > > A: outstanding I/Os get errors, subsequently issued I/Os get errors > B: outstanding I/Os get errors, subsequently issued I/Os queue > C: outstanding I/Os get reissued, subsequently issued I/Os queue > > and the following behaviors for recovery of preexisting block devices by > a future incarnation of the ublk server: > > 1: ublk devices stopped on ublk server exit (no recovery possible) > 2: ublk devices are recoverable using start/end_recovery commands > > The userspace interface allows selection of combinations of these > behaviors using flags specified at device creation time, namely: > > default behavior: A + 1 > UBLK_F_USER_RECOVERY: B + 2 > UBLK_F_USER_RECOVERY|UBLK_F_USER_RECOVERY_REISSUE: C + 2 > > The behavior A + 2 is currently unsupported. Add support for this > behavior under the new flag combination > UBLK_F_USER_RECOVERY|UBLK_F_USER_RECOVERY_FAIL_IO. > > Signed-off-by: Uday Shankar <ushankar@xxxxxxxxxxxxxxx> > --- > Changes since v2 (https://lore.kernel.org/linux-block/20240917002155.2044225-5-ushankar@xxxxxxxxxxxxxxx/): > - Clean up logic in ublk_ctrl_end_recovery > > drivers/block/ublk_drv.c | 78 ++++++++++++++++++++++++++++------- > include/uapi/linux/ublk_cmd.h | 18 ++++++++ > 2 files changed, 81 insertions(+), 15 deletions(-) > > diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c > index d5edef7bde43..f2a05dcbc58b 100644 > --- a/drivers/block/ublk_drv.c > +++ b/drivers/block/ublk_drv.c > @@ -60,10 +60,12 @@ > | UBLK_F_UNPRIVILEGED_DEV \ > | UBLK_F_CMD_IOCTL_ENCODE \ > | UBLK_F_USER_COPY \ > - | UBLK_F_ZONED) > + | UBLK_F_ZONED \ > + | UBLK_F_USER_RECOVERY_FAIL_IO) > > #define UBLK_F_ALL_RECOVERY_FLAGS (UBLK_F_USER_RECOVERY \ > - | UBLK_F_USER_RECOVERY_REISSUE) > + | UBLK_F_USER_RECOVERY_REISSUE \ > + | UBLK_F_USER_RECOVERY_FAIL_IO) > > /* All UBLK_PARAM_TYPE_* should be included here */ > #define UBLK_PARAM_TYPE_ALL \ > @@ -146,6 +148,7 @@ struct ublk_queue { > bool force_abort; > bool timeout; > bool canceling; > + bool fail_io; /* copy of dev->state == UBLK_S_DEV_FAIL_IO */ > unsigned short nr_io_ready; /* how many ios setup */ > spinlock_t cancel_lock; > struct ublk_device *dev; > @@ -690,7 +693,8 @@ static inline bool ublk_nosrv_should_reissue_outstanding(struct ublk_device *ub) > */ > static inline bool ublk_nosrv_dev_should_queue_io(struct ublk_device *ub) > { > - return ub->dev_info.flags & UBLK_F_USER_RECOVERY; > + return (ub->dev_info.flags & UBLK_F_USER_RECOVERY) && > + !(ub->dev_info.flags & UBLK_F_USER_RECOVERY_FAIL_IO); > } > > /* > @@ -700,7 +704,8 @@ static inline bool ublk_nosrv_dev_should_queue_io(struct ublk_device *ub) > */ > static inline bool ublk_nosrv_should_queue_io(struct ublk_queue *ubq) > { > - return ubq->flags & UBLK_F_USER_RECOVERY; > + return (ubq->flags & UBLK_F_USER_RECOVERY) && > + !(ubq->flags & UBLK_F_USER_RECOVERY_FAIL_IO); > } > > /* > @@ -714,6 +719,12 @@ static inline bool ublk_nosrv_should_stop_dev(struct ublk_device *ub) > return !(ub->dev_info.flags & UBLK_F_USER_RECOVERY); > } > > +static inline bool ublk_dev_in_recoverable_state(struct ublk_device *ub) > +{ > + return ub->dev_info.state == UBLK_S_DEV_QUIESCED || > + ub->dev_info.state == UBLK_S_DEV_FAIL_IO; > +} > + > static void ublk_free_disk(struct gendisk *disk) > { > struct ublk_device *ub = disk->private_data; > @@ -1275,6 +1286,10 @@ static blk_status_t ublk_queue_rq(struct blk_mq_hw_ctx *hctx, > struct request *rq = bd->rq; > blk_status_t res; > > + if (unlikely(ubq->fail_io)) { > + return BLK_STS_TARGET; > + } > + > /* fill iod to slot in io cmd buffer */ > res = ublk_setup_iod(ubq, rq); > if (unlikely(res != BLK_STS_OK)) > @@ -1625,6 +1640,7 @@ static void ublk_nosrv_work(struct work_struct *work) > { > struct ublk_device *ub = > container_of(work, struct ublk_device, nosrv_work); > + int i; > > if (ublk_nosrv_should_stop_dev(ub)) { > ublk_stop_dev(ub); > @@ -1634,7 +1650,18 @@ static void ublk_nosrv_work(struct work_struct *work) > mutex_lock(&ub->mutex); > if (ub->dev_info.state != UBLK_S_DEV_LIVE) > goto unlock; > - __ublk_quiesce_dev(ub); > + > + if (ublk_nosrv_dev_should_queue_io(ub)) { > + __ublk_quiesce_dev(ub); > + } else { > + blk_mq_quiesce_queue(ub->ub_disk->queue); > + for (i = 0; i < ub->dev_info.nr_hw_queues; i++) { > + ublk_get_queue(ub, i)->fail_io = true; > + } > + blk_mq_unquiesce_queue(ub->ub_disk->queue); > + ub->dev_info.state = UBLK_S_DEV_FAIL_IO; The above state update should be moved before blk_mq_unquiesce_queue(). Otherwise, this patch is fine. Thanks, Ming
