ovl: simplify empty checking (30c17ebf) · Commits · 戴 / test

fs/overlayfs/dir.c

+21 −29

Original line number	Diff line number	Diff line
		@@ -307,23 +307,29 @@ static struct dentry ovl_check_empty_and_clear(struct dentry dentry)
		{
		int err;
		struct dentry *ret = NULL;
		enum ovl_path_type type = ovl_path_type(dentry);
		LIST_HEAD(list);

		err = ovl_check_empty_dir(dentry, &list);
		if (err)
		if (err) {
		ret = ERR_PTR(err);
		else {
		goto out_free;
		}

		/*
		* When removing an empty opaque directory, then it makes no sense to
		* replace it with an exact replica of itself.
		*
		* If no upperdentry then skip clearing whiteouts.
		*
		* Can race with copy-up, since we don't hold the upperdir
		* mutex. Doesn't matter, since copy-up can't create a
		* non-empty directory from an empty one.
		* Can race with copy-up, since we don't hold the upperdir mutex.
		* Doesn't matter, since copy-up can't create a non-empty directory
		* from an empty one.
		*/
		if (ovl_dentry_upper(dentry))
		if (OVL_TYPE_UPPER(type) && OVL_TYPE_MERGE(type))
		ret = ovl_clear_empty(dentry, &list);
		}

		out_free:
		ovl_cache_free(&list);

		return ret;
		@@ -551,24 +557,10 @@ static int ovl_remove_and_whiteout(struct dentry *dentry, bool is_dir)
		return -EROFS;

		if (is_dir) {
		if (OVL_TYPE_MERGE_OR_LOWER(ovl_path_type(dentry))) {
		opaquedir = ovl_check_empty_and_clear(dentry);
		err = PTR_ERR(opaquedir);
		if (IS_ERR(opaquedir))
		goto out;
		} else {
		LIST_HEAD(list);

		/*
		* When removing an empty opaque directory, then it
		* makes no sense to replace it with an exact replica of
		* itself. But emptiness still needs to be checked.
		*/
		err = ovl_check_empty_dir(dentry, &list);
		ovl_cache_free(&list);
		if (err)
		goto out;
		}
		}

		err = ovl_lock_rename_workdir(workdir, upperdir);

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