Re: [PATCH v1 2/5] f2fs: Accounting large folio subpages before bio submission

[Chao Yu]

On 1/5/2026 11:30 PM, Nanzhe Zhao wrote:
> In f2fs_read_data_large_folio(), read_pages_pending is incremented only
> after the subpage has been added to the BIO.  With a heavily fragmented
> file, each new subpage can force submission of the previous BIO.
>
> If the BIO completes quickly, f2fs_finish_read_bio() may decrement
> read_pages_pending to zero and call folio_end_read() while the read loop
> is still processing other subpages of the same large folio.
>
> Fix the ordering by incrementing read_pages_pending before any possible
> BIO submission for the current subpage, matching the iomap ordering and
> preventing premature folio_end_read().
>
> Signed-off-by: Nanzhe Zhao <nzzhao@xxxxxxx>

Reviewed-by: Chao Yu <chao@xxxxxxxxxx>

Thanks,