Pagecache tags are used for dirty page writeback. Since dirtiness is
tracked on a per-THP basis, we only want to return the head page rather
than each subpage of a tagged page. All the filesystems which use huge
pages today are in-memory, so there are no tagged huge pages today.
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Reviewed-by: Jan Kara <jack@xxxxxxx>
Reviewed-by: William Kucharski <william.kucharski@xxxxxxxxxx>
---
mm/filemap.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/mm/filemap.c b/mm/filemap.c
index d5e7c2029d16..edde5dc0d28f 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2066,7 +2066,7 @@ unsigned find_get_pages_contig(struct address_space *mapping, pgoff_t index,
EXPORT_SYMBOL(find_get_pages_contig);
/**
- * find_get_pages_range_tag - find and return pages in given range matching @tag
+ * find_get_pages_range_tag - Find and return head pages matching @tag.
* @mapping: the address_space to search
* @index: the starting page index
* @end: The final page index (inclusive)
@@ -2074,8 +2074,8 @@ EXPORT_SYMBOL(find_get_pages_contig);
* @nr_pages: the maximum number of pages
* @pages: where the resulting pages are placed
*
- * Like find_get_pages, except we only return pages which are tagged with
- * @tag. We update @index to index the next page for the traversal.
+ * Like find_get_pages(), except we only return head pages which are tagged
+ * with @tag. We update @index to index the next page for the traversal.
*
* Return: the number of pages which were found.
*/
@@ -2109,9 +2109,9 @@ unsigned find_get_pages_range_tag(struct address_space *mapping, pgoff_t *index,
if (unlikely(page != xas_reload(&xas)))
goto put_page;
- pages[ret] = find_subpage(page, xas.xa_index);
+ pages[ret] = page;
if (++ret == nr_pages) {
- *index = xas.xa_index + 1;
+ *index = page->index + thp_nr_pages(page);
goto out;
}
continue;
--
2.28.0
