Add handling for controller fatal status (csts.cfs).

On any I/O timeout, check for csts.cfs==1.  If set, the controller
is reporting fatal status and we reset the controller immediately,
rather than trying to abort the timed out command.

This changeset also includes deferring the controller start portion
of the reset to a separate task.  This ensures we are always performing
a controller start operation from a consistent context.

Sponsored by:	Intel
Reviewed by:	carl

1 files changed, 18 insertions, 2 deletions

diff --git a/sys/dev/nvme/nvme_qpair.c b/sys/dev/nvme/nvme_qpair.c
index f98125f..db9abf2 100644
--- a/sys/dev/nvme/nvme_qpair.c
+++ b/sys/dev/nvme/nvme_qpair.c
@@ -98,7 +98,7 @@ nvme_qpair_construct_tracker(struct nvme_qpair *qpair, struct nvme_tracker *tr,
 	bus_dmamap_load(qpair->dma_tag, tr->prp_dma_map, tr->prp,
 	    sizeof(tr->prp), nvme_single_map, &tr->prp_bus_addr, 0);
 
-	callout_init_mtx(&tr->timer, &qpair->lock, 0);
+	callout_init(&tr->timer, 1);
 	tr->cid = cid;
 	tr->qpair = qpair;
 }
@@ -456,8 +456,24 @@ static void
 nvme_timeout(void *arg)
 {
 	struct nvme_tracker	*tr = arg;
+	struct nvme_qpair	*qpair = tr->qpair;
+	struct nvme_controller	*ctrlr = qpair->ctrlr;
+	union csts_register	csts;
 
-	nvme_ctrlr_cmd_abort(tr->qpair->ctrlr, tr->cid, tr->qpair->id,
+	csts.raw = nvme_mmio_read_4(ctrlr, csts);
+	if (csts.bits.cfs == 1) {
+		/*
+		 * The controller is reporting fatal status.  Don't bother
+		 *  trying to abort the timed out command - proceed
+		 *  immediately to a controller-level reset.
+		 */
+		device_printf(ctrlr->dev,
+		    "controller reports fatal status, resetting...\n");
+		nvme_ctrlr_reset(ctrlr);
+		return;
+	}
+
+	nvme_ctrlr_cmd_abort(ctrlr, tr->cid, qpair->id,
 	    nvme_abort_complete, tr);
 }