[PATCH v2 3/3] nvmet: pci-epf: Cleanup link state management

[Damien Le Moal]

Since the link_up boolean field of struct nvmet_pci_epf_ctrl is always
set to true when nvmet_pci_epf_start_ctrl() is called, assign true to
this field in nvmet_pci_epf_start_ctrl(). Conversely, since this field
is set to false when nvmet_pci_epf_stop_ctrl() is called, set this field
to false directly inside that function.

While at it, also add information messages to notify the user of the PCI
link state changes to help troubleshoot any link stability issues
without needing to enable debug messages.

Signed-off-by: Damien Le Moal <dlemoal at kernel.org>
Reviewed-by: Keith Busch <kbusch at kernel.org>
Reviewed-by: Niklas Cassel <cassel at kernel.org>
---
 drivers/nvme/target/pci-epf.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/nvme/target/pci-epf.c b/drivers/nvme/target/pci-epf.c
index c3d30d34f8ce..7fab7f3d79b7 100644
--- a/drivers/nvme/target/pci-epf.c
+++ b/drivers/nvme/target/pci-epf.c
@@ -2095,11 +2095,18 @@ static int nvmet_pci_epf_create_ctrl(struct nvmet_pci_epf *nvme_epf,
 
 static void nvmet_pci_epf_start_ctrl(struct nvmet_pci_epf_ctrl *ctrl)
 {
+
+	dev_info(ctrl->dev, "PCI link up\n");
+	ctrl->link_up = true;
+
 	schedule_delayed_work(&ctrl->poll_cc, NVMET_PCI_EPF_CC_POLL_INTERVAL);
 }
 
 static void nvmet_pci_epf_stop_ctrl(struct nvmet_pci_epf_ctrl *ctrl)
 {
+	dev_info(ctrl->dev, "PCI link down\n");
+	ctrl->link_up = false;
+
 	cancel_delayed_work_sync(&ctrl->poll_cc);
 
 	nvmet_pci_epf_disable_ctrl(ctrl, false);
@@ -2326,10 +2333,8 @@ static int nvmet_pci_epf_epc_init(struct pci_epf *epf)
 	if (ret)
 		goto out_clear_bar;
 
-	if (!epc_features->linkup_notifier) {
-		ctrl->link_up = true;
+	if (!epc_features->linkup_notifier)
 		nvmet_pci_epf_start_ctrl(&nvme_epf->ctrl);
-	}
 
 	return 0;
 
@@ -2345,7 +2350,6 @@ static void nvmet_pci_epf_epc_deinit(struct pci_epf *epf)
 	struct nvmet_pci_epf *nvme_epf = epf_get_drvdata(epf);
 	struct nvmet_pci_epf_ctrl *ctrl = &nvme_epf->ctrl;
 
-	ctrl->link_up = false;
 	nvmet_pci_epf_destroy_ctrl(ctrl);
 
 	nvmet_pci_epf_deinit_dma(nvme_epf);
@@ -2357,7 +2361,6 @@ static int nvmet_pci_epf_link_up(struct pci_epf *epf)
 	struct nvmet_pci_epf *nvme_epf = epf_get_drvdata(epf);
 	struct nvmet_pci_epf_ctrl *ctrl = &nvme_epf->ctrl;
 
-	ctrl->link_up = true;
 	nvmet_pci_epf_start_ctrl(ctrl);
 
 	return 0;
@@ -2368,7 +2371,6 @@ static int nvmet_pci_epf_link_down(struct pci_epf *epf)
 	struct nvmet_pci_epf *nvme_epf = epf_get_drvdata(epf);
 	struct nvmet_pci_epf_ctrl *ctrl = &nvme_epf->ctrl;
 
-	ctrl->link_up = false;
 	nvmet_pci_epf_stop_ctrl(ctrl);
 
 	return 0;
-- 
2.49.0