From 5faf6d68554808ef1b9c8647a7e8fd8a4e8cb0a5 Mon Sep 17 00:00:00 2001 From: Arie Gershberg Date: Wed, 2 Jun 2021 21:42:44 +0300 Subject: [PATCH] nvme-tcp-offload: Add controller level error recovery implementation In this patch, we implement controller level error handling and recovery. Upon an error discovered by the ULP or reset controller initiated by the nvme-core (using reset_ctrl workqueue), the ULP will initiate a controller recovery which includes teardown and re-connect of all queues. Acked-by: Igor Russkikh Signed-off-by: Arie Gershberg Signed-off-by: Prabhakar Kushwaha Signed-off-by: Omkar Kulkarni Signed-off-by: Michal Kalderon Signed-off-by: Ariel Elior Signed-off-by: Shai Malin Reviewed-by: Hannes Reinecke Reviewed-by: Himanshu Madhani Signed-off-by: David S. Miller --- drivers/nvme/host/tcp-offload.c | 127 +++++++++++++++++++++++++++++++- drivers/nvme/host/tcp-offload.h | 1 + 2 files changed, 126 insertions(+), 2 deletions(-) diff --git a/drivers/nvme/host/tcp-offload.c b/drivers/nvme/host/tcp-offload.c index d05dec9c0addc..97c1fd33adb9f 100644 --- a/drivers/nvme/host/tcp-offload.c +++ b/drivers/nvme/host/tcp-offload.c @@ -72,6 +72,23 @@ void nvme_tcp_ofld_unregister_dev(struct nvme_tcp_ofld_dev *dev) } EXPORT_SYMBOL_GPL(nvme_tcp_ofld_unregister_dev); +/** + * nvme_tcp_ofld_error_recovery() - NVMeTCP Offload library error recovery. + * function. + * @nctrl: NVMe controller instance to change to resetting. + * + * API function that change the controller state to resseting. + * Part of the overall controller reset sequence. + */ +void nvme_tcp_ofld_error_recovery(struct nvme_ctrl *nctrl) +{ + if (!nvme_change_ctrl_state(nctrl, NVME_CTRL_RESETTING)) + return; + + queue_work(nvme_reset_wq, &to_tcp_ofld_ctrl(nctrl)->err_work); +} +EXPORT_SYMBOL_GPL(nvme_tcp_ofld_error_recovery); + /** * nvme_tcp_ofld_report_queue_err() - NVMeTCP Offload report error event * callback function. Pointed to by nvme_tcp_ofld_queue->report_err. @@ -82,7 +99,8 @@ EXPORT_SYMBOL_GPL(nvme_tcp_ofld_unregister_dev); */ int nvme_tcp_ofld_report_queue_err(struct nvme_tcp_ofld_queue *queue) { - /* Placeholder - invoke error recovery flow */ + pr_err("nvme-tcp-offload queue error\n"); + nvme_tcp_ofld_error_recovery(&queue->ctrl->nctrl); return 0; } @@ -287,6 +305,28 @@ nvme_tcp_ofld_configure_io_queues(struct nvme_ctrl *nctrl, bool new) return rc; } +static void nvme_tcp_ofld_reconnect_or_remove(struct nvme_ctrl *nctrl) +{ + /* If we are resetting/deleting then do nothing */ + if (nctrl->state != NVME_CTRL_CONNECTING) { + WARN_ON_ONCE(nctrl->state == NVME_CTRL_NEW || + nctrl->state == NVME_CTRL_LIVE); + + return; + } + + if (nvmf_should_reconnect(nctrl)) { + dev_info(nctrl->device, "Reconnecting in %d seconds...\n", + nctrl->opts->reconnect_delay); + queue_delayed_work(nvme_wq, + &to_tcp_ofld_ctrl(nctrl)->connect_work, + nctrl->opts->reconnect_delay * HZ); + } else { + dev_info(nctrl->device, "Removing controller...\n"); + nvme_delete_ctrl(nctrl); + } +} + static int nvme_tcp_ofld_setup_ctrl(struct nvme_ctrl *nctrl, bool new) { struct nvme_tcp_ofld_ctrl *ctrl = to_tcp_ofld_ctrl(nctrl); @@ -410,10 +450,63 @@ nvme_tcp_ofld_teardown_io_queues(struct nvme_ctrl *nctrl, bool remove) /* Placeholder - teardown_io_queues */ } +static void nvme_tcp_ofld_reconnect_ctrl_work(struct work_struct *work) +{ + struct nvme_tcp_ofld_ctrl *ctrl = + container_of(to_delayed_work(work), + struct nvme_tcp_ofld_ctrl, + connect_work); + struct nvme_ctrl *nctrl = &ctrl->nctrl; + + ++nctrl->nr_reconnects; + + if (nvme_tcp_ofld_setup_ctrl(nctrl, false)) + goto requeue; + + dev_info(nctrl->device, "Successfully reconnected (%d attempt)\n", + nctrl->nr_reconnects); + + nctrl->nr_reconnects = 0; + + return; + +requeue: + dev_info(nctrl->device, "Failed reconnect attempt %d\n", + nctrl->nr_reconnects); + nvme_tcp_ofld_reconnect_or_remove(nctrl); +} + +static void nvme_tcp_ofld_error_recovery_work(struct work_struct *work) +{ + struct nvme_tcp_ofld_ctrl *ctrl = + container_of(work, struct nvme_tcp_ofld_ctrl, err_work); + struct nvme_ctrl *nctrl = &ctrl->nctrl; + + nvme_stop_keep_alive(nctrl); + nvme_tcp_ofld_teardown_io_queues(nctrl, false); + /* unquiesce to fail fast pending requests */ + nvme_start_queues(nctrl); + nvme_tcp_ofld_teardown_admin_queue(nctrl, false); + blk_mq_unquiesce_queue(nctrl->admin_q); + + if (!nvme_change_ctrl_state(nctrl, NVME_CTRL_CONNECTING)) { + /* state change failure is ok if we started nctrl delete */ + WARN_ON_ONCE(nctrl->state != NVME_CTRL_DELETING && + nctrl->state != NVME_CTRL_DELETING_NOIO); + + return; + } + + nvme_tcp_ofld_reconnect_or_remove(nctrl); +} + static void nvme_tcp_ofld_teardown_ctrl(struct nvme_ctrl *nctrl, bool shutdown) { - /* Placeholder - err_work and connect_work */ + struct nvme_tcp_ofld_ctrl *ctrl = to_tcp_ofld_ctrl(nctrl); + + cancel_work_sync(&ctrl->err_work); + cancel_delayed_work_sync(&ctrl->connect_work); nvme_tcp_ofld_teardown_io_queues(nctrl, shutdown); blk_mq_quiesce_queue(nctrl->admin_q); if (shutdown) @@ -428,6 +521,32 @@ static void nvme_tcp_ofld_delete_ctrl(struct nvme_ctrl *nctrl) nvme_tcp_ofld_teardown_ctrl(nctrl, true); } +static void nvme_tcp_ofld_reset_ctrl_work(struct work_struct *work) +{ + struct nvme_ctrl *nctrl = + container_of(work, struct nvme_ctrl, reset_work); + + nvme_stop_ctrl(nctrl); + nvme_tcp_ofld_teardown_ctrl(nctrl, false); + + if (!nvme_change_ctrl_state(nctrl, NVME_CTRL_CONNECTING)) { + /* state change failure is ok if we started ctrl delete */ + WARN_ON_ONCE(nctrl->state != NVME_CTRL_DELETING && + nctrl->state != NVME_CTRL_DELETING_NOIO); + + return; + } + + if (nvme_tcp_ofld_setup_ctrl(nctrl, false)) + goto out_fail; + + return; + +out_fail: + ++nctrl->nr_reconnects; + nvme_tcp_ofld_reconnect_or_remove(nctrl); +} + static int nvme_tcp_ofld_init_request(struct blk_mq_tag_set *set, struct request *rq, @@ -521,6 +640,10 @@ nvme_tcp_ofld_create_ctrl(struct device *ndev, struct nvmf_ctrl_options *opts) opts->nr_poll_queues + 1; nctrl->sqsize = opts->queue_size - 1; nctrl->kato = opts->kato; + INIT_DELAYED_WORK(&ctrl->connect_work, + nvme_tcp_ofld_reconnect_ctrl_work); + INIT_WORK(&ctrl->err_work, nvme_tcp_ofld_error_recovery_work); + INIT_WORK(&nctrl->reset_work, nvme_tcp_ofld_reset_ctrl_work); if (!(opts->mask & NVMF_OPT_TRSVCID)) { opts->trsvcid = kstrdup(__stringify(NVME_TCP_DISC_PORT), GFP_KERNEL); diff --git a/drivers/nvme/host/tcp-offload.h b/drivers/nvme/host/tcp-offload.h index 520a0ea6f4b8f..4281d1dacc94c 100644 --- a/drivers/nvme/host/tcp-offload.h +++ b/drivers/nvme/host/tcp-offload.h @@ -197,3 +197,4 @@ struct nvme_tcp_ofld_ops { /* Exported functions for lower vendor specific offload drivers */ int nvme_tcp_ofld_register_dev(struct nvme_tcp_ofld_dev *dev); void nvme_tcp_ofld_unregister_dev(struct nvme_tcp_ofld_dev *dev); +void nvme_tcp_ofld_error_recovery(struct nvme_ctrl *nctrl);