jfs: Convert inc_io to take a folio

All their callers now have a folio, so pass it in.  Remove mp_anchor()
as inc_io() was the last user.  No savings here, just cleaning up some
remnants.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>

fs/jfs/jfs_metapage.c

@@ -78,7 +78,6 @@ struct meta_anchor {
 	atomic_t io_count;
 	struct metapage *mp[MPS_PER_PAGE];
 };
-#define mp_anchor(page) ((struct meta_anchor *)page_private(page))
 
 static inline struct metapage *folio_to_mp(struct folio *folio, int offset)
 {
@@ -132,9 +131,11 @@ static inline void remove_metapage(struct folio *folio, struct metapage *mp)
 	}
 }
 
-static inline void inc_io(struct page *page)
+static inline void inc_io(struct folio *folio)
 {
-	atomic_inc(&mp_anchor(page)->io_count);
+	struct meta_anchor *anchor = folio->private;
+
+	atomic_inc(&anchor->io_count);
 }
 
 static inline void dec_io(struct folio *folio, void (*handler) (struct folio *))
@@ -166,7 +167,7 @@ static inline void remove_metapage(struct folio *folio, struct metapage *mp)
 	kunmap(&folio->page);
 }
 
-#define inc_io(page) do {} while(0)
+#define inc_io(folio) do {} while(0)
 #define dec_io(folio, handler) handler(folio)
 
 #endif
@@ -395,14 +396,14 @@ static int metapage_write_folio(struct folio *folio,
 			 * Increment counter before submitting i/o to keep
 			 * count from hitting zero before we're through
 			 */
-			inc_io(&folio->page);
+			inc_io(folio);
 			if (!bio->bi_iter.bi_size)
 				goto dump_bio;
 			submit_bio(bio);
 			nr_underway++;
 			bio = NULL;
 		} else
-			inc_io(&folio->page);
+			inc_io(folio);
 		xlen = (folio_size(folio) - offset) >> inode->i_blkbits;
 		pblock = metapage_get_blocks(inode, lblock, &xlen);
 		if (!pblock) {
@@ -496,7 +497,7 @@ static int metapage_read_folio(struct file *fp, struct folio *folio)
 		if (pblock) {
 			if (!folio->private)
 				insert_metapage(folio, NULL);
-			inc_io(&folio->page);
+			inc_io(folio);
 			if (bio)
 				submit_bio(bio);