Re: ioctl FIBMAP for dax gone in v4.17-rc1

Christoph Hellwig
2018-04-17T16:10:58Z

On Tue, Apr 17, 2018 at 10:40:59PM +0800, Xiong Zhou wrote:
> We got these in v4.17-rc1:
> 6e2608d xfs, dax: introduce xfs_dax_aops
> fb094c9 ext2, dax: introduce ext2_dax_aops
> 5f0663b ext4, dax: introduce ext4_dax_aops
>
> And we don't have ->bmap call in these aops, which may lead
> to the ioctl call failure.
>
> Do we have any plan of adding/supporting it ?
>
> xfstests generic/223 covers this issue. If we are not going
> to support this call for dax, we need to fix the testcase.

Not supporting ->bmap is a good thing as it is hightly dangerous.

The t_stripetest tool used by generic/223 should really be
rewritten to suppot FIEMAP.