nvme: return errors for hwmon init

Initializing the nvme hwmon retrieves a log from the controller. If the
controller is broken, we need to return the appropriate error so that
subsequent initialization doesn't attempt to continue.

Reported-by: Tong Zhang <ztong0001@gmail.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/nvme/host/core.c

@@ -3236,8 +3236,11 @@ int nvme_init_identify(struct nvme_ctrl *ctrl)
 	if (ret < 0)
 		return ret;
 
-	if (!ctrl->identified)
-		nvme_hwmon_init(ctrl);
+	if (!ctrl->identified) {
+		ret = nvme_hwmon_init(ctrl);
+		if (ret < 0)
+			return ret;
+	}
 
 	ctrl->identified = true;
 

drivers/nvme/host/hwmon.c

@@ -59,12 +59,8 @@ static int nvme_set_temp_thresh(struct nvme_ctrl *ctrl, int sensor, bool under,
 
 static int nvme_hwmon_get_smart_log(struct nvme_hwmon_data *data)
 {
-	int ret;
-
-	ret = nvme_get_log(data->ctrl, NVME_NSID_ALL, NVME_LOG_SMART, 0,
+	return nvme_get_log(data->ctrl, NVME_NSID_ALL, NVME_LOG_SMART, 0,
 			   NVME_CSI_NVM, &data->log, sizeof(data->log), 0);
-
-	return ret <= 0 ? ret : -EIO;
 }
 
 static int nvme_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
@@ -225,7 +221,7 @@ static const struct hwmon_chip_info nvme_hwmon_chip_info = {
 	.info	= nvme_hwmon_info,
 };
 
-void nvme_hwmon_init(struct nvme_ctrl *ctrl)
+int nvme_hwmon_init(struct nvme_ctrl *ctrl)
 {
 	struct device *dev = ctrl->dev;
 	struct nvme_hwmon_data *data;
@@ -234,7 +230,7 @@ void nvme_hwmon_init(struct nvme_ctrl *ctrl)
 
 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 	if (!data)
-		return;
+		return 0;
 
 	data->ctrl = ctrl;
 	mutex_init(&data->read_lock);
@@ -244,7 +240,7 @@ void nvme_hwmon_init(struct nvme_ctrl *ctrl)
 		dev_warn(ctrl->device,
 			"Failed to read smart log (error %d)\n", err);
 		devm_kfree(dev, data);
-		return;
+		return err;
 	}
 
 	hwmon = devm_hwmon_device_register_with_info(dev, "nvme", data,
@@ -254,4 +250,6 @@ void nvme_hwmon_init(struct nvme_ctrl *ctrl)
 		dev_warn(dev, "Failed to instantiate hwmon device\n");
 		devm_kfree(dev, data);
 	}
+
+	return 0;
 }

drivers/nvme/host/nvme.h

@@ -827,9 +827,12 @@ static inline struct nvme_ns *nvme_get_ns_from_dev(struct device *dev)
 }
 
 #ifdef CONFIG_NVME_HWMON
-void nvme_hwmon_init(struct nvme_ctrl *ctrl);
+int nvme_hwmon_init(struct nvme_ctrl *ctrl);
 #else
-static inline void nvme_hwmon_init(struct nvme_ctrl *ctrl) { }
+static inline int nvme_hwmon_init(struct nvme_ctrl *ctrl)
+{
+	return 0;
+}
 #endif
 
 u32 nvme_command_effects(struct nvme_ctrl *ctrl, struct nvme_ns *ns,