[PATCH v13 112/137] mm/filemap: Convert find_get_pages_contig to folios

Matthew Wilcox (Oracle)
2021-07-12T04:06:44Z

None of the callers of find_get_pages_contig() want tail pages. They all
use order-0 pages today, but if they were converted, they'd want folios.
So just remove the call to find_subpage() instead of replacing it with
folio_page().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
mm/filemap.c | 17 ++++++++---------
1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/mm/filemap.c b/mm/filemap.c
index 3d1a8d5f595b..e9674aabfff9 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2141,36 +2141,35 @@ unsigned find_get_pages_contig(struct address_space *mapping, pgoff_t index,
unsigned int nr_pages, struct page **pages)
{
XA_STATE(xas, &mapping->i_pages, index);
- struct page *page;
+ struct folio *folio;
unsigned int ret = 0;

if (unlikely(!nr_pages))
return 0;

rcu_read_lock();
- for (page = xas_load(&xas); page; page = xas_next(&xas)) {
- if (xas_retry(&xas, page))
+ for (folio = xas_load(&xas); folio; folio = xas_next(&xas)) {
+ if (xas_retry(&xas, folio))
continue;
/*
* If the entry has been swapped out, we can stop looking.
* No current caller is looking for DAX entries.
*/
- if (xa_is_value(page))
+ if (xa_is_value(folio))
break;

- if (!page_cache_get_speculative(page))
+ if (!folio_try_get_rcu(folio))
goto retry;

- /* Has the page moved or been split? */
- if (unlikely(page != xas_reload(&xas)))
+ if (unlikely(folio != xas_reload(&xas)))
goto put_page;

- pages[ret] = find_subpage(page, xas.xa_index);
+ pages[ret] = &folio->page;
if (++ret == nr_pages)
break;
continue;
put_page:
- put_page(page);
+ folio_put(folio);
retry:
xas_reset(&xas);
}
--
2.30.2