On Tue, Sep 17, 2019 at 03:03:33PM +0800, zhengbin (A) wrote:
>
> On 2019/9/17 1:16, Al Viro wrote:
> > On Sun, Sep 15, 2019 at 08:44:05PM -0700, Linus Torvalds wrote:
> >> On Sun, Sep 15, 2019 at 8:04 PM Al Viro <viro@xxxxxxxxxxxxxxxxxx> wrote:
> >>> Perhaps lockref_get_nested(struct lockref *lockref, unsigned int subclass)?
> >>> With s/spin_lock/spin_lock_nested/ in the body...
> >> Sure. Under the usual CONFIG_DEBUG_LOCK_ALLOC, with the non-debug case
> >> just turning into a regular lockref_get().
> >>
> >> Sounds fine to me.
> > Done and force-pushed into vfs.git#fixes
> + if (file->f_pos > 2) {
> + p = scan_positives(cursor, &dentry->d_subdirs,
> + file->f_pos - 2, &to);
> + spin_lock(&dentry->d_lock);
> + list_move(&cursor->d_child, p);
> + spin_unlock(&dentry->d_lock);
> + } else {
> + spin_lock(&dentry->d_lock);
> + list_del_init(&cursor->d_child);
> + spin_unlock(&dentry->d_lock);
> }
> +
> + dput(to);
> dput(to) should be in if if (file->f_pos > 2)? cause we dget(to) in scan_positives
dput(NULL) is a no-op
