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-rw-r--r--mm/filemap.c14
1 files changed, 13 insertions, 1 deletions
diff --git a/mm/filemap.c b/mm/filemap.c
index 0fbdc8e30dd2..23a051a7ef0f 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1693,6 +1693,11 @@ EXPORT_SYMBOL(pagecache_get_page);
* Any shadow entries of evicted pages, or swap entries from
* shmem/tmpfs, are included in the returned array.
*
+ * If it finds a Transparent Huge Page, head or tail, find_get_entries()
+ * stops at that page: the caller is likely to have a better way to handle
+ * the compound page as a whole, and then skip its extent, than repeatedly
+ * calling find_get_entries() to return all its tails.
+ *
* Return: the number of pages and shadow entries which were found.
*/
unsigned find_get_entries(struct address_space *mapping,
@@ -1724,8 +1729,15 @@ unsigned find_get_entries(struct address_space *mapping,
/* Has the page moved or been split? */
if (unlikely(page != xas_reload(&xas)))
goto put_page;
- page = find_subpage(page, xas.xa_index);
+ /*
+ * Terminate early on finding a THP, to allow the caller to
+ * handle it all at once; but continue if this is hugetlbfs.
+ */
+ if (PageTransHuge(page) && !PageHuge(page)) {
+ page = find_subpage(page, xas.xa_index);
+ nr_entries = ret + 1;
+ }
export:
indices[ret] = xas.xa_index;
entries[ret] = page;