libnvdimm, {btt, blk}: do integrity setup before add_disk()

Prior to 25520d55cdb6 ("block: Inline blk_integrity in struct gendisk")
we needed to temporarily add a zero-capacity disk before registering for
blk-integrity. But adding a zero-capacity disk caused the partition
table scanning to bail early, and this resulted in partitions not coming
up after a probe of the BTT or blk namespaces.

We can now register for integrity before the disk has been added, and
this fixes the rescan problems.

Fixes: 25520d55cdb6 ("block: Inline blk_integrity in struct gendisk")
Reported-by: Dariusz Dokupil <dariusz.dokupil@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/nvdimm/blk.c

@@ -278,8 +278,6 @@ static int nsblk_attach_disk(struct nd_namespace_blk *nsblk)
 	disk->queue		= q;
 	disk->flags		= GENHD_FL_EXT_DEVT;
 	nvdimm_namespace_disk_name(&nsblk->common, disk->disk_name);
-	set_capacity(disk, 0);
-	device_add_disk(dev, disk);
 
 	if (devm_add_action_or_reset(dev, nd_blk_release_disk, disk))
 		return -ENOMEM;
@@ -292,6 +290,7 @@ static int nsblk_attach_disk(struct nd_namespace_blk *nsblk)
 	}
 
 	set_capacity(disk, available_disk_size >> SECTOR_SHIFT);
+	device_add_disk(dev, disk);
 	revalidate_disk(disk);
 	return 0;
 }

drivers/nvdimm/btt.c

@@ -1545,8 +1545,6 @@ static int btt_blk_init(struct btt *btt)
 	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, btt->btt_queue);
 	btt->btt_queue->queuedata = btt;
 
-	set_capacity(btt->btt_disk, 0);
-	device_add_disk(&btt->nd_btt->dev, btt->btt_disk);
 	if (btt_meta_size(btt)) {
 		int rc = nd_integrity_init(btt->btt_disk, btt_meta_size(btt));
 
@@ -1558,6 +1556,7 @@ static int btt_blk_init(struct btt *btt)
 		}
 	}
 	set_capacity(btt->btt_disk, btt->nlba * btt->sector_size >> 9);
+	device_add_disk(&btt->nd_btt->dev, btt->btt_disk);
 	btt->nd_btt->size = btt->nlba * (u64)btt->sector_size;
 	revalidate_disk(btt->btt_disk);