[PATCH 08/10] Btrfs: Fix wrong device size when we are resizing the device

[Miao Xie <miaox@cn.fujitsu.com>]

total_bytes of device is just a in-memory variant which is used to record
the size of the device, and it might be changed before we resize a device,
if the resize operation fails, it will be fallbacked. But some code used it
to update on-disk metadata of the device, it would cause the problem that
on-disk metadata of the devices was not consistent. We should use the other
variant named disk_total_bytes to update the on-disk metadata of device,
because that variant is updated only when the resize operation is successful.
Fix it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
---
 fs/btrfs/disk-io.c | 3 ++-
 fs/btrfs/volumes.c | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 08e65e9..2a9560c1 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -3452,7 +3452,8 @@ static int write_all_supers(struct btrfs_root *root, int max_mirrors)
 		btrfs_set_stack_device_generation(dev_item, 0);
 		btrfs_set_stack_device_type(dev_item, dev->type);
 		btrfs_set_stack_device_id(dev_item, dev->devid);
-		btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
+		btrfs_set_stack_device_total_bytes(dev_item,
+						   dev->disk_total_bytes);
 		btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used);
 		btrfs_set_stack_device_io_align(dev_item, dev->io_align);
 		btrfs_set_stack_device_io_width(dev_item, dev->io_width);
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 0d37746..0140bff 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1489,7 +1489,7 @@ static int btrfs_add_device(struct btrfs_trans_handle *trans,
 	btrfs_set_device_io_align(leaf, dev_item, device->io_align);
 	btrfs_set_device_io_width(leaf, dev_item, device->io_width);
 	btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
-	btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes);
+	btrfs_set_device_total_bytes(leaf, dev_item, device->disk_total_bytes);
 	btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used);
 	btrfs_set_device_group(leaf, dev_item, 0);
 	btrfs_set_device_seek_speed(leaf, dev_item, 0);
-- 
1.9.3