Re: [PATCH 1/2] fs: ext4: Consolidate checks for resize of bigalloc into ext4_resize_begin

Theodore Ts'o
2021-07-01T00:48:21Z

On Thu, Jun 24, 2021 at 10:23:15AM -0400, Theodore Ts'o wrote:
> On Mon, Jun 07, 2021 at 12:15:08PM -0700, Josh Triplett wrote:
> > Two different places checked for attempts to resize a filesystem with
> > the bigalloc feature. Move the check into ext4_resize_begin, which both
> > places already call.
> >
> > Signed-off-by: Josh Triplett <josh@joshtriplett.org>
>
> Applied, thanks.

I'm going to have to revert this change, since it breaks online
resizing for bigalloc file system. The issue is that
ext4_resize_begin() is called from *three* places: for
EXT4_IOC_GROUP_ADD, EXT4_IOC_GROUP_EXTEND, and EXT4_IOC_RESIZE_FS.
The first two ioctls are used for the "old-style" online resize, and
bigalloc is not supported for those two ioctls. However, it *is*
supposed to work for EXT4_IOC_RESIZE_FS.

Unfortunately, this just caused some tests to be skipped (assuming
that this was an old kernel that didn't support this feature) and I
didn't notice it right away.

- Ted