sd: rename the scsi_disk.dev field

dev is very hard to grep for.  Give the field a more descriptive name and
documents its purpose.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220308055200.735835-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Author: Christoph Hellwig

drivers/scsi/sd.c

@@ -672,7 +672,7 @@ static struct scsi_disk *scsi_disk_get(struct gendisk *disk)
 	if (disk->private_data) {
 		sdkp = scsi_disk(disk);
 		if (scsi_device_get(sdkp->device) == 0)
-			get_device(&sdkp->dev);
+			get_device(&sdkp->disk_dev);
 		else
 			sdkp = NULL;
 	}
@@ -685,7 +685,7 @@ static void scsi_disk_put(struct scsi_disk *sdkp)
 	struct scsi_device *sdev = sdkp->device;
 
 	mutex_lock(&sd_ref_mutex);
-	put_device(&sdkp->dev);
+	put_device(&sdkp->disk_dev);
 	scsi_device_put(sdev);
 	mutex_unlock(&sd_ref_mutex);
 }
@@ -3529,14 +3529,14 @@ static int sd_probe(struct device *dev)
 					     SD_MOD_TIMEOUT);
 	}
 
-	device_initialize(&sdkp->dev);
-	sdkp->dev.parent = get_device(dev);
-	sdkp->dev.class = &sd_disk_class;
-	dev_set_name(&sdkp->dev, "%s", dev_name(dev));
+	device_initialize(&sdkp->disk_dev);
+	sdkp->disk_dev.parent = get_device(dev);
+	sdkp->disk_dev.class = &sd_disk_class;
+	dev_set_name(&sdkp->disk_dev, "%s", dev_name(dev));
 
-	error = device_add(&sdkp->dev);
+	error = device_add(&sdkp->disk_dev);
 	if (error) {
-		put_device(&sdkp->dev);
+		put_device(&sdkp->disk_dev);
 		goto out;
 	}
 
@@ -3577,7 +3577,7 @@ static int sd_probe(struct device *dev)
 
 	error = device_add_disk(dev, gd, NULL);
 	if (error) {
-		put_device(&sdkp->dev);
+		put_device(&sdkp->disk_dev);
 		goto out;
 	}
 
@@ -3628,15 +3628,15 @@ static int sd_remove(struct device *dev)
 	sdkp = dev_get_drvdata(dev);
 	scsi_autopm_get_device(sdkp->device);
 
-	device_del(&sdkp->dev);
+	device_del(&sdkp->disk_dev);
 	del_gendisk(sdkp->disk);
 	sd_shutdown(dev);
 
 	free_opal_dev(sdkp->opal_dev);
 
 	mutex_lock(&sd_ref_mutex);
 	dev_set_drvdata(dev, NULL);
-	put_device(&sdkp->dev);
+	put_device(&sdkp->disk_dev);
 	mutex_unlock(&sd_ref_mutex);
 
 	return 0;

drivers/scsi/sd.h

@@ -69,7 +69,12 @@ enum {
 
 struct scsi_disk {
 	struct scsi_device *device;
-	struct device	dev;
+
+	/*
+	 * disk_dev is used to show attributes in /sys/class/scsi_disk/,
+	 * but otherwise not really needed.  Do not use for refcounting.
+	 */
+	struct device	disk_dev;
 	struct gendisk	*disk;
 	struct opal_dev *opal_dev;
 #ifdef CONFIG_BLK_DEV_ZONED
@@ -126,7 +131,7 @@ struct scsi_disk {
 	unsigned	security : 1;
 	unsigned	ignore_medium_access_errors : 1;
 };
-#define to_scsi_disk(obj) container_of(obj,struct scsi_disk,dev)
+#define to_scsi_disk(obj) container_of(obj, struct scsi_disk, disk_dev)
 
 static inline struct scsi_disk *scsi_disk(struct gendisk *disk)
 {