block: move the ->devnode callback to struct block_device_operations

There really isn't any good reason to stash a method directly into
struct gendisk.  Move it together with the other block device
operations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/genhd.c

@@ -1497,8 +1497,8 @@ static char *block_devnode(struct device *dev, umode_t *mode,
 {
 	struct gendisk *disk = dev_to_disk(dev);
 
-	if (disk->devnode)
-		return disk->devnode(disk, mode);
+	if (disk->fops->devnode)
+		return disk->fops->devnode(disk, mode);
 	return NULL;
 }
 

drivers/block/pktcdvd.c

@@ -2679,6 +2679,11 @@ static unsigned int pkt_check_events(struct gendisk *disk,
 	return attached_disk->fops->check_events(attached_disk, clearing);
 }
 
+static char *pkt_devnode(struct gendisk *disk, umode_t *mode)
+{
+	return kasprintf(GFP_KERNEL, "pktcdvd/%s", disk->disk_name);
+}
+
 static const struct block_device_operations pktcdvd_ops = {
 	.owner =		THIS_MODULE,
 	.open =			pkt_open,
@@ -2686,13 +2691,9 @@ static const struct block_device_operations pktcdvd_ops = {
 	.ioctl =		pkt_ioctl,
 	.compat_ioctl =		blkdev_compat_ptr_ioctl,
 	.check_events =		pkt_check_events,
+	.devnode =		pkt_devnode,
 };
 
-static char *pktcdvd_devnode(struct gendisk *gd, umode_t *mode)
-{
-	return kasprintf(GFP_KERNEL, "pktcdvd/%s", gd->disk_name);
-}
-
 /*
  * Set up mapping from pktcdvd device to CD-ROM device.
  */
@@ -2748,7 +2749,6 @@ static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
 	disk->fops = &pktcdvd_ops;
 	disk->flags = GENHD_FL_REMOVABLE;
 	strcpy(disk->disk_name, pd->name);
-	disk->devnode = pktcdvd_devnode;
 	disk->private_data = pd;
 	disk->queue = blk_alloc_queue(GFP_KERNEL);
 	if (!disk->queue)

include/linux/blkdev.h

@@ -1697,6 +1697,7 @@ struct block_device_operations {
 	void (*swap_slot_free_notify) (struct block_device *, unsigned long);
 	int (*report_zones)(struct gendisk *, sector_t sector,
 			unsigned int nr_zones, report_zones_cb cb, void *data);
+	char *(*devnode)(struct gendisk *disk, umode_t *mode);
 	struct module *owner;
 	const struct pr_ops *pr_ops;
 };

include/linux/genhd.h

@@ -191,7 +191,6 @@ struct gendisk {
                                          * disks that can't be partitioned. */
 
 	char disk_name[DISK_NAME_LEN];	/* name of major driver */
-	char *(*devnode)(struct gendisk *gd, umode_t *mode);
 
 	unsigned short events;		/* supported events */
 	unsigned short event_flags;	/* flags related to event processing */