On 5/23/21 10:57 AM, Mike Christie wrote:
> For aborts, qedi needs to cleanup the FW then send the TMF from a worker
> thread. While it's doing these the cmd could complete normally and the TMF
> could time out. libiscsi would then complete the iscsi_task which will
> call into the driver to cleanup the driver level resources while it still
> might be accessig them for the cleanup/abort.
>
> This has iscsi_eh_abort keep the iscsi_task ref if the TMF times out, so
> qedi does not have to worry about if the task been freed while in use
typo: "been" -> "being"
> and does not need to get its own ref.
>
> Signed-off-by: Mike Christie <michael.christie@xxxxxxxxxx>
> ---iscsi_stop_conn
> drivers/scsi/libiscsi.c | 15 ++++++++++++++-
> include/scsi/libiscsi.h | 1 +
> 2 files changed, 15 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
> index 8222db4f8fef..9247f70d2daa 100644
> --- a/drivers/scsi/libiscsi.c
> +++ b/drivers/scsi/libiscsi.c
> @@ -573,6 +573,11 @@ static bool cleanup_queued_task(struct iscsi_task *task)
> __iscsi_put_task(task);
> }
>
> + if (conn->session->running_aborted_task == task) {
> + conn->session->running_aborted_task = NULL;
> + __iscsi_put_task(task);
> + }
> +
> if (conn->task == task) {iscsi_stop_conn
> conn->task = NULL;
> __iscsi_put_task(task);
> @@ -2334,6 +2339,7 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
> iscsi_start_tx(conn);
> goto success_unlocked;
> case TMF_TIMEDOUT:
> + session->running_aborted_task = task;
> spin_unlock_bh(&session->frwd_lock);
> iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
> goto failed_unlocked;
> @@ -2367,7 +2373,14 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
> failed_unlocked:
> ISCSI_DBG_EH(session, "abort failed [sc %p itt 0x%x]\n", sc,
> task ? task->itt : 0);
> - iscsi_put_task(task);
> + /*
> + * The driver might be accessing the task so hold the ref. The conn
> + * stop cleanup will drop the ref after ep_disconnect so we know the
> + * driver's no longer touching the task.
> + */
> + if (!session->running_aborted_task)
> + iscsi_put_task(task);
> +
> iscsi_put_conn(conn->cls_conn);
> mutex_unlock(&session->eh_mutex);
> return FAILED;
> diff --git a/include/scsi/libiscsi.h b/include/scsi/libiscsi.h
> index 9d7908265afe..4ee233e5a6ff 100644
> --- a/include/scsi/libiscsi.h
> +++ b/include/scsi/libiscsi.h
> @@ -276,6 +276,7 @@ struct iscsi_session {
> struct iscsi_tm tmhdr;
> struct timer_list tmf_timer;
> int tmf_state; /* see TMF_INITIAL, etc.*/
> + struct iscsi_task *running_aborted_task;
>
> /* iSCSI session-wide sequencing */
> uint32_t cmdsn;
>
Reviewed-by: Lee Duncan <lduncan@xxxxxxxx>
