mm/filemap: Add filemap_add_folio()

Convert __add_to_page_cache_locked() into __filemap_add_folio().
Add an assertion to it that (for !hugetlbfs), the folio is naturally
aligned within the file.  Move the prototype from mm.h to pagemap.h.
Convert add_to_page_cache_lru() into filemap_add_folio().  Add a
compatibility wrapper for unconverted callers.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Howells <dhowells@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>

1 files changed, 7 insertions, 0 deletions

diff --git a/mm/folio-compat.c b/mm/folio-compat.c
index 6de3cd78a4ae..6b19bc4ed6b0 100644
--- a/mm/folio-compat.c
+++ b/mm/folio-compat.c
@@ -108,3 +108,10 @@ void lru_cache_add(struct page *page)
 	folio_add_lru(page_folio(page));
 }
 EXPORT_SYMBOL(lru_cache_add);
+
+int add_to_page_cache_lru(struct page *page, struct address_space *mapping,
+		pgoff_t index, gfp_t gfp)
+{
+	return filemap_add_folio(mapping, page_folio(page), index, gfp);
+}
+EXPORT_SYMBOL(add_to_page_cache_lru);