btrfs-progs: convert: Fix a regression that ext2_save/image is not readonly

The new convert treats the convert image as a normal file, without any
special flags and permissions.

This is different from original code:
1) Permission changed from 0400 to 0600
2) Inode lacks READONLY flag

This makes we can read-write mount the ext2 image and cause rollback
failure.

Follow old code behavior, use 0400 permission and add back READONLY
flag to fix it.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/ctree.h b/ctree.h
index dda72d0e..b9fb732c 100644
--- a/ctree.h
+++ b/ctree.h
@@ -2578,6 +2578,8 @@ int check_dir_conflict(struct btrfs_root *root, char *name, int namelen,
 		u64 dir, u64 index);
 int btrfs_new_inode(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 		u64 ino, u32 mode);
+int btrfs_change_inode_flags(struct btrfs_trans_handle *trans,
+			     struct btrfs_root *root, u64 ino, u64 flags);
 int btrfs_add_link(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 		   u64 ino, u64 parent_ino, char *name, int namelen,
 		   u8 type, u64 *index, int add_backref);