Re: [PATCH] ext4: cancel dirty accounting for folios without buffers

[Zhu Jia]

On Thu, Jun 25, 2026 at 01:18:31PM +0200, Jan Kara wrote:
> On Wed 24-06-26 21:29:58, Zhang Yi wrote:
> > On 6/24/2026 8:32 PM, Jan Kara wrote:
> > > On Wed 24-06-26 17:52:06, Zhu Jia wrote:
> > > > The reason I left the tags unchanged in this version is that I was not sure
> > > > whether it is appropriate for ext4 to open-code xarray tag cleanup directly.
> > > > 
> > > > If you think this is the right direction, I can add the helper back and
> > > > send a v2.
> > > 
> > > That was a good judgement! Playing with xarray tags like this in filesystem
> > > code is certainly not a good thing. For now, I'd leave the xarray tags
> > > dangling - they will be eventually synced with reality on next writeback
> > > attempt. If this inconsistency of tags needs to be fixed, the fix belongs
> > > to the generic code (so that it can be used in other places as well).
> > 
> > Yes, I agree. Directly clearing the tag via open code is not a good
> > approach. However, I took a look at the !nr_to_submit branch in
> > ext4_bio_write_folio(), and it seems to have a similar simple handling
> > pattern - it directly calls __folio_start_writeback() and
> > folio_end_writeback(), which appears to be an elegant way to clear them.
> > Could we also call these two helpers just after folio_cancel_dirty()
> > here?
>
> Right, that would be actually doable there and would keep things more
> consistent so I think that's a good idea! Thanks!

Thanks Jan and Yi, your discussion makes sense. I will send v2 shortly.

Thanks,
Jia