diff options
| author | Amir Goldstein <amir73il@gmail.com> | 2023-07-07 11:20:41 +0300 |
|---|---|---|
| committer | Amir Goldstein <amir73il@gmail.com> | 2023-08-12 19:02:50 +0300 |
| commit | d9544c1b0d9e14a66936814dcc8a85861ea1b99f (patch) | |
| tree | b8c8a2f1daee13141cd107888e932902873569d4 /fs/overlayfs/super.c | |
| parent | b0504bfe1b8acdcfb5ef466581d930835ef3c49e (diff) | |
ovl: store persistent uuid/fsid with uuid=on
With uuid=on, store a persistent uuid in xattr on the upper dir to
give the overlayfs instance a persistent identifier.
This also makes f_fsid persistent and more reliable for reporting
fid info in fanotify events.
uuid=on is not supported on non-upper overlayfs or with upper fs
that does not support xattrs.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Diffstat (limited to 'fs/overlayfs/super.c')
| -rw-r--r-- | fs/overlayfs/super.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index c2bab6106e98..9107e5482578 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -777,6 +777,10 @@ static int ovl_make_workdir(struct super_block *sb, struct ovl_fs *ofs, ofs->config.index = false; pr_warn("...falling back to index=off.\n"); } + if (ovl_has_fsid(ofs)) { + ofs->config.uuid = OVL_UUID_NULL; + pr_warn("...falling back to uuid=null.\n"); + } /* * xattr support is required for persistent st_ino. * Without persistent st_ino, xino=auto falls back to xino=off. @@ -1427,9 +1431,9 @@ int ovl_fill_super(struct super_block *sb, struct fs_context *fc) if (!ovl_origin_uuid(ofs) && ofs->numfs > 1) { pr_warn("The uuid=off requires a single fs for lower and upper, falling back to uuid=null.\n"); ofs->config.uuid = OVL_UUID_NULL; - } else if (ovl_has_fsid(ofs)) { - /* Use per instance uuid/fsid */ - uuid_gen(&sb->s_uuid); + } else if (ovl_has_fsid(ofs) && ovl_upper_mnt(ofs)) { + /* Use per instance persistent uuid/fsid */ + ovl_init_uuid_xattr(sb, ofs, &ctx->upper); } if (!ovl_force_readonly(ofs) && ofs->config.index) { |