On Wed, Jul 16, 2025 at 2:47 AM NeilBrown <neil@xxxxxxxxxx> wrote:
>
> Only take the dir lock when needed, rather than for the whole loop.
>
> Signed-off-by: NeilBrown <neil@xxxxxxxxxx>
Reviewed-by: Amir Goldstein <amir73il@xxxxxxxxx>
> ---
> fs/overlayfs/readdir.c | 14 +++++++++-----
> 1 file changed, 9 insertions(+), 5 deletions(-)
>
> diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c
> index 95d5284daf8d..b0f9e5a00c1a 100644
> --- a/fs/overlayfs/readdir.c
> +++ b/fs/overlayfs/readdir.c
> @@ -1122,7 +1122,6 @@ static int ovl_workdir_cleanup_recurse(struct ovl_fs *ofs, const struct path *pa
> if (err)
> goto out;
>
> - inode_lock_nested(dir, I_MUTEX_PARENT);
> list_for_each_entry(p, &list, l_node) {
> struct dentry *dentry;
>
> @@ -1137,16 +1136,21 @@ static int ovl_workdir_cleanup_recurse(struct ovl_fs *ofs, const struct path *pa
> err = -EINVAL;
> break;
> }
> - dentry = ovl_lookup_upper(ofs, p->name, path->dentry, p->len);
> + dentry = ovl_lookup_upper_unlocked(ofs, p->name, path->dentry, p->len);
> if (IS_ERR(dentry))
> continue;
> - if (dentry->d_inode)
> - err = ovl_workdir_cleanup(ofs, dir, path->mnt, dentry, level);
> + if (dentry->d_inode) {
> + err = ovl_parent_lock(path->dentry, dentry);
> + if (!err) {
> + err = ovl_workdir_cleanup(ofs, dir, path->mnt,
> + dentry, level);
> + ovl_parent_unlock(path->dentry);
> + }
> + }
> dput(dentry);
> if (err)
> break;
> }
> - inode_unlock(dir);
> out:
> ovl_cache_free(&list);
> return err;
> --
> 2.49.0
>
