removing the remaining blockdev_direct_IO users

removing the remaining blockdev_direct_IO users

[Christoph Hellwig]

Hi all,

we have 7 users of blockdev_direct_IO and one of the lower-level
__blockdev_direct_IO left, and I'd really like to get rid of them.

The filesystems are affs, fat, hfs, hfsplus, jfs, nilfs2, udf and ocfs2,
and you are the relevant maintainers.  In 7.2 exfat converted entirely
to iomap, which would be a really good example for a "simple" file
system.  Another options especially for the file systems supporting
foreign formats would be to just drop direct I/O support and reduce
the support burden.

Re: removing the remaining blockdev_direct_IO users

[Viacheslav Dubeyko]

On Fri, 2026-07-10 at 07:07 +0200, Christoph Hellwig wrote:
> Hi all,
> 
> we have 7 users of blockdev_direct_IO and one of the lower-level
> __blockdev_direct_IO left, and I'd really like to get rid of them.
> 
> The filesystems are affs, fat, hfs, hfsplus, jfs, nilfs2, udf and
> ocfs2,
> and you are the relevant maintainers.  In 7.2 exfat converted
> entirely
> to iomap, which would be a really good example for a "simple" file
> system.  Another options especially for the file systems supporting
> foreign formats would be to just drop direct I/O support and reduce
> the support burden.

I like the idea. I think we can try to switch HFS/HFS+ and NILFS2 on
iomap approach. Do you have some initial patches for this? Which
particular commit(s) converted the exfat to iomap? It will be good to
take a deeper look into this conversion to estimate the complexity of
HFS/HFS+, NILFS2 modifications.

Thanks,
Slava.