On 2023/7/17 21:40, Matthew Wilcox wrote:
On Mon, Jul 17, 2023 at 09:25:58PM +0800, Peng Zhang wrote:
+++ b/mm/page_io.c
@@ -406,19 +406,19 @@ static void sio_read_complete(struct kiocb *iocb, long ret)
if (ret == sio->len) {
for (p = 0; p < sio->pages; p++) {
- struct page *page = sio->bvec[p].bv_page;
+ struct folio *folio = page_folio(sio->bvec[p].bv_page);
- SetPageUptodate(page);
- unlock_page(page);
+ folio_mark_uptodate(folio);
+ folio_unlock(folio);
}
I'm kind of shocked this works today. Usually bvecs coalesce adjacent
pages into a single entry, so you need to use a real iterator like
bio_for_each_folio_all() to extract individual pages from a bvec.
Maybe the sio bvec is constructed inefficiently.
I think Kent had some bvec folio iterators in progress?
I'll convert bio_first_page_all() to bio_first_folio_all() in a v2.
count_vm_events(PSWPIN, sio->pages);
} else {
for (p = 0; p < sio->pages; p++) {
- struct page *page = sio->bvec[p].bv_page;
+ struct folio *folio = page_folio(sio->bvec[p].bv_page);
- SetPageError(page);
- ClearPageUptodate(page);
- unlock_page(page);
+ folio_set_error(folio);
+ folio_clear_uptodate(folio);
+ folio_unlock(folio);
Similar questions to the last patch -- who checks the error flag on this
page/folio, and isn't the folio already !uptodate?
Yes, the folio is already !uptodate. I'll drop this line.
Maybe wait_dev_supers() in fs/btrfs/disk-io.c checks the PageError()?
}
pr_alert_ratelimited("Read-error on swap-device\n");
}
--
2.25.1
--
Best Regards,
Peng
