Re: [PATCH] xfs: preserve inode versioning across remounts

Eric Sandeen
2020-07-15T19:04:27Z

On 7/15/20 11:09 AM, Christoph Hellwig wrote:
> On Tue, Jul 14, 2020 at 03:11:34PM -0700, Eric Sandeen wrote:
>> The MS_I_VERSION mount flag is exposed via the VFS, as documented
>> in the mount manpages etc; see the iversion and noiversion mount
>> options in mount(8).
>>
>> As a result, mount -o remount looks for this option in /proc/mounts
>> and will only send the I_VERSION flag back in during remount it it
>> is present. Since it's not there, a remount will /remove/ the
>> I_VERSION flag at the vfs level, and iversion functionality is lost.
>>
>> xfs v5 superblocks intend to always have i_version enabled; it is
>> set as a default at mount time, but is lost during remount for the
>> reasons above.
>
> Looks good, this fixes the new mount API conversion, as the old code
> automatically added it. Maybe this wants a Fixes tag.
>
> Reviewed-by: Christoph Hellwig <hch@lst.de>

AFAICT (and from testing) this behavior predates the mount API conversion.

Thanks,
-Eric