jfs; Convert __invalidate_metapages to use a folio

Retrieve a folio from the page cache instead of a page.  Saves a
couple of calls to compound_head().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>

Author: Matthew Wilcox (Oracle)

fs/jfs/jfs_metapage.c

@@ -791,7 +791,6 @@ void __invalidate_metapages(struct inode *ip, s64 addr, int len)
 	struct address_space *mapping =
 		JFS_SBI(ip->i_sb)->direct_inode->i_mapping;
 	struct metapage *mp;
-	struct page *page;
 	unsigned int offset;
 
 	/*
@@ -800,11 +799,12 @@ void __invalidate_metapages(struct inode *ip, s64 addr, int len)
 	 */
 	for (lblock = addr & ~(BlocksPerPage - 1); lblock < addr + len;
 	     lblock += BlocksPerPage) {
-		page = find_lock_page(mapping, lblock >> l2BlocksPerPage);
-		if (!page)
+		struct folio *folio = filemap_lock_folio(mapping,
+				lblock >> l2BlocksPerPage);
+		if (IS_ERR(folio))
 			continue;
 		for (offset = 0; offset < PAGE_SIZE; offset += PSIZE) {
-			mp = page_to_mp(page, offset);
+			mp = page_to_mp(&folio->page, offset);
 			if (!mp)
 				continue;
 			if (mp->index < addr)
@@ -817,8 +817,8 @@ void __invalidate_metapages(struct inode *ip, s64 addr, int len)
 			if (mp->lsn)
 				remove_from_logsync(mp);
 		}
-		unlock_page(page);
-		put_page(page);
+		folio_unlock(folio);
+		folio_put(folio);
 	}
 }