f2fs: Use a folio in f2fs_write_compressed_pages()

Remove accesses to page->index and an unnecessary reference to
page->mapping.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Author: Matthew Wilcox (Oracle)

fs/f2fs/compress.c

@@ -1282,6 +1282,7 @@ static int f2fs_write_compressed_pages(struct compress_ctx *cc,
 		.encrypted = fscrypt_inode_uses_fs_layer_crypto(cc->inode) ?
 									1 : 0,
 	};
+	struct folio *folio;
 	struct dnode_of_data dn;
 	struct node_info ni;
 	struct compress_io_ctx *cic;
@@ -1293,7 +1294,7 @@ static int f2fs_write_compressed_pages(struct compress_ctx *cc,
 
 	/* we should bypass data pages to proceed the kworker jobs */
 	if (unlikely(f2fs_cp_error(sbi))) {
-		mapping_set_error(cc->rpages[0]->mapping, -EIO);
+		mapping_set_error(inode->i_mapping, -EIO);
 		goto out_free;
 	}
 
@@ -1320,7 +1321,8 @@ static int f2fs_write_compressed_pages(struct compress_ctx *cc,
 			goto out_put_dnode;
 	}
 
-	psize = (loff_t)(cc->rpages[last_index]->index + 1) << PAGE_SHIFT;
+	folio = page_folio(cc->rpages[last_index]);
+	psize = folio_pos(folio) + folio_size(folio);
 
 	err = f2fs_get_node_info(fio.sbi, dn.nid, &ni, false);
 	if (err)
@@ -1343,7 +1345,7 @@ static int f2fs_write_compressed_pages(struct compress_ctx *cc,
 
 	for (i = 0; i < cc->valid_nr_cpages; i++) {
 		f2fs_set_compressed_page(cc->cpages[i], inode,
-					cc->rpages[i + 1]->index, cic);
+				page_folio(cc->rpages[i + 1])->index, cic);
 		fio.compressed_page = cc->cpages[i];
 
 		fio.old_blkaddr = data_blkaddr(dn.inode, dn.node_page,