Now ublk_abort_queue() is moved to ublk char device release handler,
meantime our request queue is "quiesced" because either ->canceling was
set from uring_cmd cancel function or all IOs are inflight and can't be
completed by ublk server, things becomes easy much:
- all uring_cmd are done, so we needn't to mark io as UBLK_IO_FLAG_ABORTED
for handling completion from uring_cmd
- ublk char device is closed, no one can hold IO request reference any more,
so we can simply complete this request or requeue it for ublk_nosrv_should_reissue_outstanding.
Reviewed-by: Uday Shankar <ushankar@xxxxxxxxxxxxxxx>
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
drivers/block/ublk_drv.c | 82 ++++++++++------------------------------
1 file changed, 20 insertions(+), 62 deletions(-)
diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index bf708e9e9a12..2de7b2bd409d 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -122,15 +122,6 @@ struct ublk_uring_cmd_pdu {
*/
#define UBLK_IO_FLAG_OWNED_BY_SRV 0x02
-/*
- * IO command is aborted, so this flag is set in case of
- * !UBLK_IO_FLAG_ACTIVE.
- *
- * After this flag is observed, any pending or new incoming request
- * associated with this io command will be failed immediately
- */
-#define UBLK_IO_FLAG_ABORTED 0x04
-
/*
* UBLK_IO_FLAG_NEED_GET_DATA is set because IO command requires
* get data buffer address from ublksrv.
@@ -1083,12 +1074,6 @@ static inline void __ublk_complete_rq(struct request *req)
unsigned int unmapped_bytes;
blk_status_t res = BLK_STS_OK;
- /* called from ublk_abort_queue() code path */
- if (io->flags & UBLK_IO_FLAG_ABORTED) {
- res = BLK_STS_IOERR;
- goto exit;
- }
-
/* failed read IO if nothing is read */
if (!io->res && req_op(req) == REQ_OP_READ)
io->res = -EIO;
@@ -1138,47 +1123,6 @@ static void ublk_complete_rq(struct kref *ref)
__ublk_complete_rq(req);
}
-static void ublk_do_fail_rq(struct request *req)
-{
- struct ublk_queue *ubq = req->mq_hctx->driver_data;
-
- if (ublk_nosrv_should_reissue_outstanding(ubq->dev))
- blk_mq_requeue_request(req, false);
- else
- __ublk_complete_rq(req);
-}
-
-static void ublk_fail_rq_fn(struct kref *ref)
-{
- struct ublk_rq_data *data = container_of(ref, struct ublk_rq_data,
- ref);
- struct request *req = blk_mq_rq_from_pdu(data);
-
- ublk_do_fail_rq(req);
-}
-
-/*
- * Since ublk_rq_task_work_cb always fails requests immediately during
- * exiting, __ublk_fail_req() is only called from abort context during
- * exiting. So lock is unnecessary.
- *
- * Also aborting may not be started yet, keep in mind that one failed
- * request may be issued by block layer again.
- */
-static void __ublk_fail_req(struct ublk_queue *ubq, struct ublk_io *io,
- struct request *req)
-{
- WARN_ON_ONCE(io->flags & UBLK_IO_FLAG_ACTIVE);
-
- if (ublk_need_req_ref(ubq)) {
- struct ublk_rq_data *data = blk_mq_rq_to_pdu(req);
-
- kref_put(&data->ref, ublk_fail_rq_fn);
- } else {
- ublk_do_fail_rq(req);
- }
-}
-
static void ubq_complete_io_cmd(struct ublk_io *io, int res,
unsigned issue_flags)
{
@@ -1667,10 +1611,26 @@ static void ublk_commit_completion(struct ublk_device *ub,
ublk_put_req_ref(ubq, req);
}
+static void __ublk_fail_req(struct ublk_queue *ubq, struct ublk_io *io,
+ struct request *req)
+{
+ WARN_ON_ONCE(io->flags & UBLK_IO_FLAG_ACTIVE);
+
+ if (ublk_nosrv_should_reissue_outstanding(ubq->dev))
+ blk_mq_requeue_request(req, false);
+ else {
+ io->res = -EIO;
+ __ublk_complete_rq(req);
+ }
+}
+
/*
- * Called from ubq_daemon context via cancel fn, meantime quiesce ublk
- * blk-mq queue, so we are called exclusively with blk-mq and ubq_daemon
- * context, so everything is serialized.
+ * Called from ublk char device release handler, when any uring_cmd is
+ * done, meantime request queue is "quiesced" since all inflight requests
+ * can't be completed because ublk server is dead.
+ *
+ * So no one can hold our request IO reference any more, simply ignore the
+ * reference, and complete the request immediately
*/
static void ublk_abort_queue(struct ublk_device *ub, struct ublk_queue *ubq)
{
@@ -1687,10 +1647,8 @@ static void ublk_abort_queue(struct ublk_device *ub, struct ublk_queue *ubq)
* will do it
*/
rq = blk_mq_tag_to_rq(ub->tag_set.tags[ubq->q_id], i);
- if (rq && blk_mq_request_started(rq)) {
- io->flags |= UBLK_IO_FLAG_ABORTED;
+ if (rq && blk_mq_request_started(rq))
__ublk_fail_req(ubq, io, rq);
- }
}
}
}
--
2.47.0
