[PATCH v6 09/18] nvme: Implement cross-controller reset completion

[Mohamed Khalfella <mkhalfella@purestorage.com>]

An nvme source controller that issues CCR command expects to receive an
NVME_AER_NOTICE_CCR_COMPLETED when pending CCR succeeds or fails. Add
ctrl->ccr_work to read NVME_LOG_CCR logpage and wakeup threads waiting
on CCR completion.

Signed-off-by: Mohamed Khalfella <mkhalfella@purestorage.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
---
 drivers/nvme/host/core.c | 50 +++++++++++++++++++++++++++++++++++++++-
 drivers/nvme/host/nvme.h |  1 +
 2 files changed, 50 insertions(+), 1 deletion(-)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index c8e3129d84a8..5509b58b51db 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -1959,7 +1959,8 @@ EXPORT_SYMBOL_GPL(nvme_set_queue_count);
 
 #define NVME_AEN_SUPPORTED \
 	(NVME_AEN_CFG_NS_ATTR | NVME_AEN_CFG_FW_ACT | \
-	 NVME_AEN_CFG_ANA_CHANGE | NVME_AEN_CFG_DISC_CHANGE)
+	 NVME_AEN_CFG_ANA_CHANGE | NVME_AEN_CFG_CCR_COMPLETE | \
+	 NVME_AEN_CFG_DISC_CHANGE)
 
 static void nvme_enable_aen(struct nvme_ctrl *ctrl)
 {
@@ -5023,6 +5024,48 @@ static void nvme_get_fw_slot_info(struct nvme_ctrl *ctrl)
 	kfree(log);
 }
 
+static void nvme_ccr_work(struct work_struct *work)
+{
+	struct nvme_ctrl *ctrl = container_of(work, struct nvme_ctrl, ccr_work);
+	struct nvme_ccr_entry *ccr;
+	struct nvme_ccr_log_entry *entry;
+	struct nvme_ccr_log *log;
+	int num_entries, ret, i;
+	unsigned long flags;
+
+	log = kmalloc_obj(*log);
+	if (!log)
+		return;
+
+	ret = nvme_get_log(ctrl, 0, NVME_LOG_CCR, 0x01,
+			   0x00, log, sizeof(*log), 0);
+	if (ret)
+		goto out;
+
+	spin_lock_irqsave(&ctrl->lock, flags);
+	num_entries = min(le16_to_cpu(log->ne), NVMF_CCR_PER_PAGE);
+	for (i = 0; i < num_entries; i++) {
+		entry = &log->entries[i];
+		if (entry->ccrs == NVME_CCR_STATUS_IN_PROGRESS)
+			continue;
+
+		list_for_each_entry(ccr, &ctrl->ccr_list, list) {
+			struct nvme_ctrl *ictrl = ccr->ictrl;
+
+			if (ictrl->cntlid != le16_to_cpu(entry->icid) ||
+			    ictrl->ciu != entry->ciu)
+				continue;
+
+			/* Complete matching entry */
+			ccr->ccrs = entry->ccrs;
+			complete(&ccr->complete);
+		}
+	}
+	spin_unlock_irqrestore(&ctrl->lock, flags);
+out:
+	kfree(log);
+}
+
 static void nvme_fw_act_work(struct work_struct *work)
 {
 	struct nvme_ctrl *ctrl = container_of(work,
@@ -5099,6 +5142,9 @@ static bool nvme_handle_aen_notice(struct nvme_ctrl *ctrl, u32 result)
 	case NVME_AER_NOTICE_DISC_CHANGED:
 		ctrl->aen_result = result;
 		break;
+	case NVME_AER_NOTICE_CCR_COMPLETED:
+		queue_work(nvme_wq, &ctrl->ccr_work);
+		break;
 	default:
 		dev_warn(ctrl->device, "async event result %08x\n", result);
 	}
@@ -5287,6 +5333,7 @@ void nvme_stop_ctrl(struct nvme_ctrl *ctrl)
 	nvme_stop_failfast_work(ctrl);
 	flush_work(&ctrl->async_event_work);
 	cancel_work_sync(&ctrl->fw_act_work);
+	cancel_work_sync(&ctrl->ccr_work);
 	if (ctrl->ops->stop_ctrl)
 		ctrl->ops->stop_ctrl(ctrl);
 }
@@ -5412,6 +5459,7 @@ int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
 	ctrl->quirks = quirks;
 	ctrl->numa_node = NUMA_NO_NODE;
 	INIT_WORK(&ctrl->scan_work, nvme_scan_work);
+	INIT_WORK(&ctrl->ccr_work, nvme_ccr_work);
 	INIT_WORK(&ctrl->async_event_work, nvme_async_event_work);
 	INIT_WORK(&ctrl->fw_act_work, nvme_fw_act_work);
 	INIT_WORK(&ctrl->delete_work, nvme_delete_ctrl_work);
diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index 8da75a15ac04..7096f1e4f84e 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -431,6 +431,7 @@ struct nvme_ctrl {
 	struct nvme_effects_log *effects;
 	struct xarray cels;
 	struct work_struct scan_work;
+	struct work_struct ccr_work;
 	struct work_struct async_event_work;
 	struct delayed_work ka_work;
 	struct delayed_work failfast_work;
-- 
2.55.0