| Message ID | 20220831155136.23434-4-ZiyangZhang@linux.alibaba.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | ublk_drv: add USER_RECOVERY support | expand |
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@linux.alibaba.com> > --- > 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
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); + + if (ubq->flags & UBLK_F_USER_RECOVERY) + return true; + return false; +} + +/* + * TODO: UBLK_F_USER_RECOVERY_REISSUE 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_reissue(struct ublk_device *ub) +{ + struct ublk_queue *ubq = ublk_get_queue(ub, 0); + + if ((ubq->flags & UBLK_F_USER_RECOVERY) && + (ubq->flags & UBLK_F_USER_RECOVERY_REISSUE)) + return true; + return false; +} + static void ublk_free_disk(struct gendisk *disk) { struct ublk_device *ub = disk->private_data; diff --git a/include/uapi/linux/ublk_cmd.h b/include/uapi/linux/ublk_cmd.h index 677edaab2b66..7f7e6f44cec5 100644 --- a/include/uapi/linux/ublk_cmd.h +++ b/include/uapi/linux/ublk_cmd.h @@ -17,6 +17,8 @@ #define UBLK_CMD_STOP_DEV 0x07 #define UBLK_CMD_SET_PARAMS 0x08 #define UBLK_CMD_GET_PARAMS 0x09 +#define UBLK_CMD_START_USER_RECOVERY 0x10 +#define UBLK_CMD_END_USER_RECOVERY 0x11 /* * IO commands, issued by ublk server, and handled by ublk driver. @@ -74,9 +76,14 @@ */ #define UBLK_F_NEED_GET_DATA (1UL << 2) +#define UBLK_F_USER_RECOVERY (1UL << 3) + +#define UBLK_F_USER_RECOVERY_REISSUE (1UL << 4) + /* device state */ #define UBLK_S_DEV_DEAD 0 #define UBLK_S_DEV_LIVE 1 +#define UBLK_S_DEV_RECOVERING 2 /* shipped via sqe->cmd of io_uring command */ struct ublksrv_ctrl_cmd {
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@linux.alibaba.com> --- drivers/block/ublk_drv.c | 31 ++++++++++++++++++++++++++++++- include/uapi/linux/ublk_cmd.h | 7 +++++++ 2 files changed, 37 insertions(+), 1 deletion(-)