From: James Smart <james.smart@broadcom.com>
Date: Fri, 16 Oct 2020 14:06:27 -0700
Subject: nvme-fc: fix io timeout to abort I/O
Patch-mainline: v5.10-rc1
Git-commit: 52793d62a696e9188092eb0817fb1219ee5729ff
References: bsc#1187076
Currently, an I/O timeout unconditionally invokes
nvme_fc_error_recovery() which checks for LIVE or CONNECTING state. If
live, the routine resets the controller which initiates a reconnect -
which is valid. If CONNECTING, err_work is scheduled. Err_work then
calls the terminate_io routine, which also checks for CONNECTING and
noops any further action on outstanding I/O. The result is nothing
happened to the timed out io. As such, if the command was dropped on
the wire, it will never timeout / complete, and the connect process
will hang.
Change the behavior of the io timeout routine to unconditionally abort
the I/O. I/O completion handling will note that an io failed due to an
abort and will terminate the connection / association as needed. If the
abort was unable to happen, continue with a call to
nvme_fc_error_recovery(). To ensure something different happens in
nvme_fc_error_recovery() rework it so at it will abort all I/Os on the
association to force a failure.
As I/O aborts now may occur outside of delete_association, counting for
completion must be wary and only count those aborted during
delete_association when TERMIO is set on the controller.
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
[dwagner: - updated context for __nvme_fc_abort_outstanding_ios
- adapted cdw10 usage in nvme_fc_timeout
- removed unused disls in nvme_fc_delete_association]
Acked-by: Daniel Wagner <dwagner@suse.de>
---
drivers/nvme/host/fc.c | 105 +++++++++++++++++++++++++++++++------------------
1 file changed, 67 insertions(+), 38 deletions(-)
--- a/drivers/nvme/host/fc.c
+++ b/drivers/nvme/host/fc.c
@@ -1516,8 +1516,10 @@ static int
opstate = atomic_xchg(&op->state, FCPOP_STATE_ABORTED);
if (opstate != FCPOP_STATE_ACTIVE)
atomic_set(&op->state, opstate);
- else if (test_bit(FCCTRL_TERMIO, &ctrl->flags))
+ else if (test_bit(FCCTRL_TERMIO, &ctrl->flags)) {
+ op->flags |= FCOP_FLAGS_TERMIO;
ctrl->iocnt++;
+ }
spin_unlock_irqrestore(&ctrl->lock, flags);
if (opstate != FCPOP_STATE_ACTIVE)
@@ -1553,7 +1555,8 @@ static inline void
if (opstate == FCPOP_STATE_ABORTED) {
spin_lock_irqsave(&ctrl->lock, flags);
- if (test_bit(FCCTRL_TERMIO, &ctrl->flags)) {
+ if (test_bit(FCCTRL_TERMIO, &ctrl->flags) &&
+ op->flags & FCOP_FLAGS_TERMIO) {
if (!--ctrl->iocnt)
wake_up(&ctrl->ioabort_wait);
}
@@ -2119,15 +2122,20 @@ nvme_fc_timeout(struct request *rq, bool
{
struct nvme_fc_fcp_op *op = blk_mq_rq_to_pdu(rq);
struct nvme_fc_ctrl *ctrl = op->ctrl;
+ struct nvme_fc_cmd_iu *cmdiu = &op->cmd_iu;
+ struct nvme_command *sqe = &cmdiu->sqe;
/*
- * we can't individually ABTS an io without affecting the queue,
- * thus killing the queue, and thus the association.
- * So resolve by performing a controller reset, which will stop
- * the host/io stack, terminate the association on the link,
- * and recreate an association on the link.
+ * Attempt to abort the offending command. Command completion
+ * will detect the aborted io and will fail the connection.
*/
- nvme_fc_error_recovery(ctrl, "io timeout error");
+ dev_info(ctrl->ctrl.device,
+ "NVME-FC{%d.%d}: io timeout: opcode %d fctype %d w10/11: "
+ "x%08x/x%08x\n",
+ ctrl->cnum, op->queue->qnum, sqe->common.opcode,
+ sqe->connect.fctype, sqe->common.cdw10[0], sqe->common.cdw10[0]);
+ if (__nvme_fc_abort_op(ctrl, op))
+ nvme_fc_error_recovery(ctrl, "io timeout abort failed");
/*
* the io abort has been initiated. Have the reset timer
@@ -2413,6 +2421,7 @@ nvme_fc_complete_rq(struct request *rq)
struct nvme_fc_ctrl *ctrl = op->ctrl;
atomic_set(&op->state, FCPOP_STATE_IDLE);
+ op->flags &= ~FCOP_FLAGS_TERMIO;
nvme_fc_unmap_data(ctrl, rq, op);
nvme_complete_rq(rq);
@@ -2772,24 +2781,17 @@ nvme_fc_create_association(struct nvme_f
}
/*
- * This routine stops operation of the controller on the host side.
- * On the host os stack side: Admin and IO queues are stopped,
- * outstanding ios on them terminated via FC ABTS.
- * On the link side: the association is terminated.
+ * This routine runs through all outstanding commands on the association
+ * and aborts them. This routine is typically be called by the
+ * delete_association routine. It is also called due to an error during
+ * reconnect. In that scenario, it is most likely a command that initializes
+ * the controller, including fabric Connect commands on io queues, that
+ * may have timed out or failed thus the io must be killed for the connect
+ * thread to see the error.
*/
static void
-nvme_fc_delete_association(struct nvme_fc_ctrl *ctrl)
+__nvme_fc_abort_outstanding_ios(struct nvme_fc_ctrl *ctrl, bool start_queues)
{
- unsigned long flags;
-
- if (!test_and_clear_bit(ASSOC_ACTIVE, &ctrl->flags))
- return;
-
- spin_lock_irqsave(&ctrl->lock, flags);
- set_bit(FCCTRL_TERMIO, &ctrl->flags);
- ctrl->iocnt = 0;
- spin_unlock_irqrestore(&ctrl->lock, flags);
-
/*
* If io queues are present, stop them and terminate all outstanding
* ios on them. As FC allocates FC exchange for each io, the
@@ -2807,6 +2809,8 @@ nvme_fc_delete_association(struct nvme_f
blk_mq_tagset_busy_iter(&ctrl->tag_set,
nvme_fc_terminate_exchange, &ctrl->ctrl);
blk_mq_tagset_wait_completed_request(&ctrl->tag_set);
+ if (start_queues)
+ nvme_start_queues(&ctrl->ctrl);
}
/*
@@ -2823,13 +2827,33 @@ nvme_fc_delete_association(struct nvme_f
/*
* clean up the admin queue. Same thing as above.
- * use blk_mq_tagset_busy_itr() and the transport routine to
- * terminate the exchanges.
*/
blk_mq_quiesce_queue(ctrl->ctrl.admin_q);
blk_mq_tagset_busy_iter(&ctrl->admin_tag_set,
nvme_fc_terminate_exchange, &ctrl->ctrl);
blk_mq_tagset_wait_completed_request(&ctrl->admin_tag_set);
+}
+
+/*
+ * This routine stops operation of the controller on the host side.
+ * On the host os stack side: Admin and IO queues are stopped,
+ * outstanding ios on them terminated via FC ABTS.
+ * On the link side: the association is terminated.
+ */
+static void
+nvme_fc_delete_association(struct nvme_fc_ctrl *ctrl)
+{
+ unsigned long flags;
+
+ if (!test_and_clear_bit(ASSOC_ACTIVE, &ctrl->flags))
+ return;
+
+ spin_lock_irqsave(&ctrl->lock, flags);
+ set_bit(FCCTRL_TERMIO, &ctrl->flags);
+ ctrl->iocnt = 0;
+ spin_unlock_irqrestore(&ctrl->lock, flags);
+
+ __nvme_fc_abort_outstanding_ios(ctrl, false);
/* kill the aens as they are a separate path */
nvme_fc_abort_aen_ops(ctrl);
@@ -2931,22 +2955,27 @@ static void
__nvme_fc_terminate_io(struct nvme_fc_ctrl *ctrl)
{
/*
- * if state is connecting - the error occurred as part of a
- * reconnect attempt. The create_association error paths will
- * clean up any outstanding io.
- *
- * if it's a different state - ensure all pending io is
- * terminated. Given this can delay while waiting for the
- * aborted io to return, we recheck adapter state below
- * before changing state.
+ * if state is CONNECTING - the error occurred as part of a
+ * reconnect attempt. Abort any ios on the association and
+ * let the create_association error paths resolve things.
*/
- if (ctrl->ctrl.state != NVME_CTRL_CONNECTING) {
- nvme_stop_keep_alive(&ctrl->ctrl);
-
- /* will block will waiting for io to terminate */
- nvme_fc_delete_association(ctrl);
+ if (ctrl->ctrl.state == NVME_CTRL_CONNECTING) {
+ __nvme_fc_abort_outstanding_ios(ctrl, true);
+ return;
}
+ /*
+ * For any other state, kill the association. As this routine
+ * is a common io abort routine for resetting and such, after
+ * the association is terminated, ensure that the state is set
+ * to CONNECTING.
+ */
+
+ nvme_stop_keep_alive(&ctrl->ctrl);
+
+ /* will block will waiting for io to terminate */
+ nvme_fc_delete_association(ctrl);
+
if (ctrl->ctrl.state != NVME_CTRL_CONNECTING &&
!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING))
dev_err(ctrl->ctrl.device,