From ca45275cd6b63e917eef681f9f15978b96afdbbe Mon Sep 17 00:00:00 2001 From: Vyacheslav Yurkov Date: Thu, 27 May 2021 19:45:46 +0200 Subject: ovl: add ovl_allow_offline_changes() helper Allows to check whether any of extended features are enabled Signed-off-by: Vyacheslav Yurkov Reviewed-by: Amir Goldstein Signed-off-by: Miklos Szeredi --- fs/overlayfs/overlayfs.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'fs/overlayfs/overlayfs.h') diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h index 2433cc030c87..e9b3e7880fc0 100644 --- a/fs/overlayfs/overlayfs.h +++ b/fs/overlayfs/overlayfs.h @@ -263,6 +263,18 @@ static inline bool ovl_open_flags_need_copy_up(int flags) return ((OPEN_FMODE(flags) & FMODE_WRITE) || (flags & O_TRUNC)); } +static inline bool ovl_allow_offline_changes(struct ovl_fs *ofs) +{ + /* + * To avoid regressions in existing setups with overlay lower offline + * changes, we allow lower changes only if none of the new features + * are used. + */ + return (!ofs->config.index && !ofs->config.metacopy && + !ofs->config.redirect_dir && ofs->config.xino != OVL_XINO_ON); +} + + /* util.c */ int ovl_want_write(struct dentry *dentry); void ovl_drop_write(struct dentry *dentry); -- cgit v1.2.3