From: Josef Bacik <jbacik@fb.com>
Date: Wed, 16 May 2018 14:51:19 -0400
Subject: [PATCH] nbd: use bd_set_size when updating disk size
Git-commit: 9e2b19675d1338d2a38e99194756f2db44a081df
Patch-mainline: v4.18-rc1
References: bsc#1104967,FATE#325924

When we stopped relying on the bdev everywhere I broke updating the
block device size on the fly, which ceph relies on.  We can't just do
set_capacity, we also have to do bd_set_size so things like parted will
notice the device size change.

Fixes: 29eaadc ("nbd: stop using the bdev everywhere")
cc: stable@vger.kernel.org
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Hannes Reinecke <hare@suse.com>
---
 drivers/block/nbd.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index b709abf3cb79..64278f472efe 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -234,9 +234,18 @@ static void nbd_size_clear(struct nbd_device *nbd)
 static void nbd_size_update(struct nbd_device *nbd)
 {
 	struct nbd_config *config = nbd->config;
+	struct block_device *bdev = bdget_disk(nbd->disk, 0);
+
 	blk_queue_logical_block_size(nbd->disk->queue, config->blksize);
 	blk_queue_physical_block_size(nbd->disk->queue, config->blksize);
 	set_capacity(nbd->disk, config->bytesize >> 9);
+	if (bdev) {
+		if (bdev->bd_disk)
+			bd_set_size(bdev, config->bytesize);
+		else
+			bdev->bd_invalidated = 1;
+		bdput(bdev);
+	}
 	kobject_uevent(&nbd_to_dev(nbd)->kobj, KOBJ_CHANGE);
 }
 
@@ -1114,7 +1123,6 @@ static int nbd_start_device_ioctl(struct nbd_device *nbd, struct block_device *b
 	if (ret)
 		return ret;
 
-	bd_set_size(bdev, config->bytesize);
 	if (max_part)
 		bdev->bd_invalidated = 1;
 	mutex_unlock(&nbd->config_lock);
-- 
2.12.3