On Fri, 11 Jul 2025, Amir Goldstein wrote:
> On Fri, Jul 11, 2025 at 1:21 AM NeilBrown <neil@xxxxxxxxxx> wrote:
> >
> > ovl_cleanup_index() takes a lock on the directory and then does a lookup
> > and possibly one of two different cleanups.
> > This patch narrows the locking to use the _unlocked() versions of the
> > lookup and one cleanup, and just takes the lock for the other cleanup.
> >
> > A subsequent patch will take the lock into the cleanup.
> >
> > Signed-off-by: NeilBrown <neil@xxxxxxxxxx>
> > ---
> > fs/overlayfs/util.c | 9 ++++-----
> > 1 file changed, 4 insertions(+), 5 deletions(-)
> >
> > diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
> > index 9ce9fe62ef28..7369193b11ec 100644
> > --- a/fs/overlayfs/util.c
> > +++ b/fs/overlayfs/util.c
> > @@ -1107,21 +1107,20 @@ static void ovl_cleanup_index(struct dentry *dentry)
> > goto out;
> > }
> >
> > - inode_lock_nested(dir, I_MUTEX_PARENT);
> > - index = ovl_lookup_upper(ofs, name.name, indexdir, name.len);
> > + index = ovl_lookup_upper_unlocked(ofs, name.name, indexdir, name.len);
> > err = PTR_ERR(index);
> > if (IS_ERR(index)) {
> > index = NULL;
> > } else if (ovl_index_all(dentry->d_sb)) {
> > /* Whiteout orphan index to block future open by handle */
> > + inode_lock_nested(dir, I_MUTEX_PARENT);
>
> Don't we need to verify that index wasn't moved with
> parent_lock(indexdi, index)?
Yes, thanks. I've change it to use lock_parent() (or whatever we end up
calling it).
Thanks,
NeilBrown
>
> Thanks,
> Amir.
>
> > err = ovl_cleanup_and_whiteout(OVL_FS(dentry->d_sb),
> > indexdir, index);
> > + inode_unlock(dir);
> > } else {
> > /* Cleanup orphan index entries */
> > - err = ovl_cleanup(ofs, dir, index);
> > + err = ovl_cleanup_unlocked(ofs, indexdir, index);
> > }
> > -
> > - inode_unlock(dir);
> > if (err)
> > goto fail;
> >
> > --
> > 2.49.0
> >
>
