| Message ID | 20241014053645.17619-1-hawkxiang.cpp@gmail.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | [v2] scsi: libiscsi: Set expecting_cc_ua flag when stop_conn | expand |
On 10/14/24 12:36 AM, Xiang Zhang wrote: > Initiator need to recover session and reconnect to target, after calling stop_conn. And target will rebuild new session info, and mark ASC_POWERON_RESET ua sense for scsi devices belong to the target(device reset). After recovery, first scsi command(scmd) request to target will get ASC_POWERON_RESET(ua sense) + SAM_STAT_CHECK_CONDITION(status) in response. > For command's response coming, according to scsi function calling: "scsi_done --> scsi_complete --> scsi_decide_disposition --> scsi_check_sense", if expecting_cc_ua = 0, scmd response with ASC_POWERON_RESET(ua sense) will make scsi_complete ignore "cmd->retries <= cmd->allowed", fail directly. It will cause SCSI return io_error to upper layer without retry. > If we set expecting_cc_ua=1 in fail_scsi_tasks, scsi_complete will retry scmd which is response with ASC_POWERON_RESET. The scmd second request to target can successful, because target will clear ASC_POWERON_RESET in device pending ua_sense_list after first scmd request. > > Signed-off-by: Xiang Zhang <hawkxiang.cpp@gmail.com> > --- > V1 -> V2: Fix build variable 'sc' is uninitialized warning(Reported-by: kernel test robot <lkp@intel.com>). > --- > drivers/scsi/libiscsi.c | 7 ++++--- > 1 file changed, 4 insertions(+), 3 deletions(-) > > diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c > index 0fda8905eabd..f6bfe0c4f8a4 100644 > --- a/drivers/scsi/libiscsi.c > +++ b/drivers/scsi/libiscsi.c > @@ -621,6 +621,7 @@ static void __fail_scsi_task(struct iscsi_task *task, int err) > if (cleanup_queued_task(task)) > return; > > + sc = task->sc; > if (task->state == ISCSI_TASK_PENDING) { > /* > * cmd never made it to the xmit thread, so we should not count > @@ -629,12 +630,12 @@ static void __fail_scsi_task(struct iscsi_task *task, int err) > conn->session->queued_cmdsn--; > /* it was never sent so just complete like normal */ > state = ISCSI_TASK_COMPLETED; > - } else if (err == DID_TRANSPORT_DISRUPTED) > + } else if (err == DID_TRANSPORT_DISRUPTED) { > state = ISCSI_TASK_ABRT_SESS_RECOV; > - else > + sc->device->expecting_cc_ua = 1; > + } else > state = ISCSI_TASK_ABRT_TMF; > > - sc = task->sc; > sc->result = err << 16; > scsi_set_resid(sc, scsi_bufflen(sc)); > iscsi_complete_task(task, state); This should be fixed in a common way like I mentioned in the other thread.
diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c index 0fda8905eabd..f6bfe0c4f8a4 100644 --- a/drivers/scsi/libiscsi.c +++ b/drivers/scsi/libiscsi.c @@ -621,6 +621,7 @@ static void __fail_scsi_task(struct iscsi_task *task, int err) if (cleanup_queued_task(task)) return; + sc = task->sc; if (task->state == ISCSI_TASK_PENDING) { /* * cmd never made it to the xmit thread, so we should not count @@ -629,12 +630,12 @@ static void __fail_scsi_task(struct iscsi_task *task, int err) conn->session->queued_cmdsn--; /* it was never sent so just complete like normal */ state = ISCSI_TASK_COMPLETED; - } else if (err == DID_TRANSPORT_DISRUPTED) + } else if (err == DID_TRANSPORT_DISRUPTED) { state = ISCSI_TASK_ABRT_SESS_RECOV; - else + sc->device->expecting_cc_ua = 1; + } else state = ISCSI_TASK_ABRT_TMF; - sc = task->sc; sc->result = err << 16; scsi_set_resid(sc, scsi_bufflen(sc)); iscsi_complete_task(task, state);
Initiator need to recover session and reconnect to target, after calling stop_conn. And target will rebuild new session info, and mark ASC_POWERON_RESET ua sense for scsi devices belong to the target(device reset). After recovery, first scsi command(scmd) request to target will get ASC_POWERON_RESET(ua sense) + SAM_STAT_CHECK_CONDITION(status) in response. For command's response coming, according to scsi function calling: "scsi_done --> scsi_complete --> scsi_decide_disposition --> scsi_check_sense", if expecting_cc_ua = 0, scmd response with ASC_POWERON_RESET(ua sense) will make scsi_complete ignore "cmd->retries <= cmd->allowed", fail directly. It will cause SCSI return io_error to upper layer without retry. If we set expecting_cc_ua=1 in fail_scsi_tasks, scsi_complete will retry scmd which is response with ASC_POWERON_RESET. The scmd second request to target can successful, because target will clear ASC_POWERON_RESET in device pending ua_sense_list after first scmd request. Signed-off-by: Xiang Zhang <hawkxiang.cpp@gmail.com> --- V1 -> V2: Fix build variable 'sc' is uninitialized warning(Reported-by: kernel test robot <lkp@intel.com>). --- drivers/scsi/libiscsi.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)