On 12.10.2018 09:37, Qu Wenruo wrote:
> The member log_root_transid is never used.
> It's always kept untouched even when updating log tree root.
>
> And populating it without introducing new incompat flags could easily
> cause back-compatibility problems.
> So just mark it unused.
>
> Signed-off-by: Qu Wenruo <wqu@xxxxxxxx>
> ---
> changelog:
> v2:
> Remove the redundant comment.
> ---
> fs/btrfs/ctree.h | 5 +----
> 1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
> index 53af9f5253f4..7adf5f4dcda4 100644
> --- a/fs/btrfs/ctree.h
> +++ b/fs/btrfs/ctree.h
> @@ -214,8 +214,7 @@ struct btrfs_super_block {
> __le64 chunk_root;
> __le64 log_root;
>
> - /* this will help find the new super based on the log root */
> - __le64 log_root_transid;
> + __le64 __unused_log_root_transid;
why do you keep insisting on having "log_root_transid" in the name of
this member? It was never used on-disk so for all intents and purposes
log_root_transid doesn't mean anything? No need to resend, I'm sure
David will change it on commit, nut I'm just curious.
> __le64 total_bytes;
> __le64 bytes_used;
> __le64 root_dir_objectid;
> @@ -2317,8 +2316,6 @@ BTRFS_SETGET_STACK_FUNCS(super_chunk_root_level, struct btrfs_super_block,
> chunk_root_level, 8);
> BTRFS_SETGET_STACK_FUNCS(super_log_root, struct btrfs_super_block,
> log_root, 64);
> -BTRFS_SETGET_STACK_FUNCS(super_log_root_transid, struct btrfs_super_block,
> - log_root_transid, 64);
> BTRFS_SETGET_STACK_FUNCS(super_log_root_level, struct btrfs_super_block,
> log_root_level, 8);
> BTRFS_SETGET_STACK_FUNCS(super_total_bytes, struct btrfs_super_block,
>
