f2fs: trival cleanup in move_data_block()

Trival cleanups:
- relocate set_summary() before its use
- relocate "allocate block address" to correct place
- remove unneeded f2fs_wait_on_page_writeback()
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/gc.c

@@ -1169,8 +1169,6 @@ static int move_data_block(struct inode *inode, block_t bidx,
 	if (err)
 		goto put_out;
 
-	set_summary(&sum, dn.nid, dn.ofs_in_node, ni.version);
-
 	/* read page */
 	fio.page = page;
 	fio.new_blkaddr = fio.old_blkaddr = dn.data_blkaddr;
@@ -1207,6 +1205,9 @@ static int move_data_block(struct inode *inode, block_t bidx,
 		}
 	}
 
+	set_summary(&sum, dn.nid, dn.ofs_in_node, ni.version);
+
+	/* allocate block address */
 	f2fs_allocate_data_block(fio.sbi, NULL, fio.old_blkaddr, &newaddr,
 				&sum, type, NULL);
 
@@ -1233,9 +1234,6 @@ static int move_data_block(struct inode *inode, block_t bidx,
 	set_page_writeback(fio.encrypted_page);
 	ClearPageError(page);
 
-	/* allocate block address */
-	f2fs_wait_on_page_writeback(dn.node_page, NODE, true, true);
-
 	fio.op = REQ_OP_WRITE;
 	fio.op_flags = REQ_SYNC;
 	fio.new_blkaddr = newaddr;