struct buffer_head {
unsigned long b_state; /* buffer state bitmap (see above) */
struct buffer_head *b_this_page;/* circular list of page's buffers */
- struct page *b_page; /* the page this bh is mapped to */
+ union {
+ struct page *b_page; /* the page this bh is mapped to */
+ struct folio *b_folio; /* the folio this bh is mapped to */
+ };
sector_t b_blocknr; /* start block number */
size_t b_size; /* size of mapping */