On Wed, Jul 23, 2025 at 06:18:24PM +0800, Chi Zhiling wrote:
> From: Chi Zhiling <chizhiling@xxxxxxxxxx>
>
> Setting IOCB_NOWAIT in filemap_get_pages() for AIO is only used to
> indicate not to block in the filemap_update_page(), with no other purpose.
> Moreover, in filemap_read(), IOCB_NOWAIT will be set again for AIO.
>
> Therefore, adding a parameter to the filemap_update_page function to
> explicitly indicate not to block serves the same purpose as indicating
> through iocb->ki_flags, thus avoiding modifications to iocb->ki_flags.
>
> This patch does not change the original logic and is preparation for the
> next patch.
Passing multiple booleans to a function is an antipattern.
Particularly in this case, since we could just pass iocb->ki_flags
to the function.
But I think there's a less complicated way to do what you want.
Just don't call filemap_update_page() if there are uptodate folios
in the batch:
+++ b/mm/filemap.c
@@ -2616,9 +2616,10 @@ static int filemap_get_pages(struct kiocb *iocb, size_t count,
goto err;
}
if (!folio_test_uptodate(folio)) {
- if ((iocb->ki_flags & IOCB_WAITQ) &&
- folio_batch_count(fbatch) > 1)
- iocb->ki_flags |= IOCB_NOWAIT;
+ if (folio_batch_count(fbatch) > 1) {
+ err = -EAGAIN;
+ goto err;
+ }
err = filemap_update_page(iocb, mapping, count, folio,
need_uptodate);
if (err)
