ChangeLog, Makefile.in, initialize.c, .del-io.h~72680822, openfs.c:
  Makefile.in (ELF_SO_VERSION): Bump version to be 2.4 since we've added
  	a new field to the io_channel (app_data).
  io.h: Add a new element to the io_channel structure, app_data.
  initialize.c, openfs.c: Set io->app_data to point at the filesystem handle.

diff --git a/lib/ext2fs/initialize.c b/lib/ext2fs/initialize.c
index 3e6028b..1537968 100644
--- a/lib/ext2fs/initialize.c
+++ b/lib/ext2fs/initialize.c
@@ -81,6 +81,7 @@
 	retval = manager->open(name, IO_FLAG_RW, &fs->io);
 	if (retval)
 		goto cleanup;
+	fs->io->app_data = fs;
 	fs->device_name = malloc(strlen(name)+1);
 	if (!fs->device_name) {
 		retval = ENOMEM;