277 	if (!(cgrp->root->subsys_mask & (1 << ss->id)))  in cgroup_e_css()
413 #define for_each_root(root)						\  argument
414 	list_for_each_entry((root), &cgroup_roots, root_list)
633 		BUG_ON(cgrp1->root != cgrp2->root);  in compare_css_sets()
642 		if (cgrp1->root == new_cgrp->root) {  in compare_css_sets()
663 	struct cgroup_root *root = cgrp->root;  in find_existing_css_set()  local
675 		if (root->subsys_mask & (1UL << i)) {  in find_existing_css_set()
829 		if (c->root == cgrp->root)  in find_css_set()
855 	return root_cgrp->root;  in cgroup_root_from_kf()
858 static int cgroup_init_root_id(struct cgroup_root *root)  in cgroup_init_root_id()  argument
864 	id = idr_alloc_cyclic(&cgroup_hierarchy_idr, root, 0, 0, GFP_KERNEL);  in cgroup_init_root_id()
868 	root->hierarchy_id = id;  in cgroup_init_root_id()
872 static void cgroup_exit_root_id(struct cgroup_root *root)  in cgroup_exit_root_id()  argument
876 	if (root->hierarchy_id) {  in cgroup_exit_root_id()
877 		idr_remove(&cgroup_hierarchy_idr, root->hierarchy_id);  in cgroup_exit_root_id()
878 		root->hierarchy_id = 0;  in cgroup_exit_root_id()
882 static void cgroup_free_root(struct cgroup_root *root)  in cgroup_free_root()  argument
884 	if (root) {  in cgroup_free_root()
886 		WARN_ON_ONCE(root->hierarchy_id);  in cgroup_free_root()
888 		idr_destroy(&root->cgroup_idr);  in cgroup_free_root()
889 		kfree(root);  in cgroup_free_root()
893 static void cgroup_destroy_root(struct cgroup_root *root)  in cgroup_destroy_root()  argument
895 	struct cgroup *cgrp = &root->cgrp;  in cgroup_destroy_root()
900 	BUG_ON(atomic_read(&root->nr_cgrps));  in cgroup_destroy_root()
904 	rebind_subsystems(&cgrp_dfl_root, root->subsys_mask);  in cgroup_destroy_root()
919 	if (!list_empty(&root->root_list)) {  in cgroup_destroy_root()
920 		list_del(&root->root_list);  in cgroup_destroy_root()
924 	cgroup_exit_root_id(root);  in cgroup_destroy_root()
928 	kernfs_destroy_root(root->kf_root);  in cgroup_destroy_root()
929 	cgroup_free_root(root);  in cgroup_destroy_root()
934 					    struct cgroup_root *root)  in cset_cgroup_from_root()  argument
942 		res = &root->cgrp;  in cset_cgroup_from_root()
949 			if (c->root == root) {  in cset_cgroup_from_root()
965 					    struct cgroup_root *root)  in task_cgroup_from_root()  argument
972 	return cset_cgroup_from_root(task_css_set(task), root);  in task_cgroup_from_root()
1009 	    !(cgrp->root->flags & CGRP_ROOT_NOPREFIX))  in cgroup_file_name()
1099 			new_ss_mask &= cgrp->root->subsys_mask;  in cgroup_calc_child_subsys_mask()
1231 		if (css_next_child(NULL, cgroup_css(&ss->root->cgrp, ss)))  in rebind_subsystems()
1235 		if (ss->root != &cgrp_dfl_root && dst_root != &cgrp_dfl_root)  in rebind_subsystems()
1268 			cgroup_clear_dir(&ss->root->cgrp, 1 << ssid);  in rebind_subsystems()
1278 		src_root = ss->root;  in rebind_subsystems()
1285 		ss->root = dst_root;  in rebind_subsystems()
1316 	struct cgroup_root *root = cgroup_root_from_kf(kf_root);  in cgroup_show_options()  local
1321 		if (root->subsys_mask & (1 << ssid))  in cgroup_show_options()
1323 	if (root->flags & CGRP_ROOT_NOPREFIX)  in cgroup_show_options()
1325 	if (root->flags & CGRP_ROOT_XATTR)  in cgroup_show_options()
1329 	if (strlen(root->release_agent_path))  in cgroup_show_options()
1331 				root->release_agent_path);  in cgroup_show_options()
1334 	if (test_bit(CGRP_CPUSET_CLONE_CHILDREN, &root->cgrp.flags))  in cgroup_show_options()
1336 	if (strlen(root->name))  in cgroup_show_options()
1337 		seq_show_option(seq, "name", root->name);  in cgroup_show_options()
1497 	struct cgroup_root *root = cgroup_root_from_kf(kf_root);  in cgroup_remount()  local
1501 	if (root == &cgrp_dfl_root) {  in cgroup_remount()
1513 	if (opts.subsys_mask != root->subsys_mask || opts.release_agent)  in cgroup_remount()
1517 	added_mask = opts.subsys_mask & ~root->subsys_mask;  in cgroup_remount()
1518 	removed_mask = root->subsys_mask & ~opts.subsys_mask;  in cgroup_remount()
1521 	if ((opts.flags ^ root->flags) ||  in cgroup_remount()
1522 	    (opts.name && strcmp(opts.name, root->name))) {  in cgroup_remount()
1524 		       opts.flags, opts.name ?: "", root->flags, root->name);  in cgroup_remount()
1530 	if (!list_empty(&root->cgrp.self.children)) {  in cgroup_remount()
1535 	ret = rebind_subsystems(root, added_mask);  in cgroup_remount()
1543 		strcpy(root->release_agent_path, opts.release_agent);  in cgroup_remount()
1625 static void init_cgroup_root(struct cgroup_root *root,  in init_cgroup_root()  argument
1628 	struct cgroup *cgrp = &root->cgrp;  in init_cgroup_root()
1630 	INIT_LIST_HEAD(&root->root_list);  in init_cgroup_root()
1631 	atomic_set(&root->nr_cgrps, 1);  in init_cgroup_root()
1632 	cgrp->root = root;  in init_cgroup_root()
1634 	idr_init(&root->cgroup_idr);  in init_cgroup_root()
1636 	root->flags = opts->flags;  in init_cgroup_root()
1638 		strcpy(root->release_agent_path, opts->release_agent);  in init_cgroup_root()
1640 		strcpy(root->name, opts->name);  in init_cgroup_root()
1642 		set_bit(CGRP_CPUSET_CLONE_CHILDREN, &root->cgrp.flags);  in init_cgroup_root()
1645 static int cgroup_setup_root(struct cgroup_root *root, unsigned int ss_mask)  in cgroup_setup_root()  argument
1648 	struct cgroup *root_cgrp = &root->cgrp;  in cgroup_setup_root()
1655 	ret = cgroup_idr_alloc(&root->cgroup_idr, root_cgrp, 1, 2, GFP_NOWAIT);  in cgroup_setup_root()
1675 	ret = cgroup_init_root_id(root);  in cgroup_setup_root()
1679 	root->kf_root = kernfs_create_root(&cgroup_kf_syscall_ops,  in cgroup_setup_root()
1682 	if (IS_ERR(root->kf_root)) {  in cgroup_setup_root()
1683 		ret = PTR_ERR(root->kf_root);  in cgroup_setup_root()
1686 	root_cgrp->kn = root->kf_root->kn;  in cgroup_setup_root()
1688 	if (root == &cgrp_dfl_root)  in cgroup_setup_root()
1697 	ret = rebind_subsystems(root, ss_mask);  in cgroup_setup_root()
1706 	list_add(&root->root_list, &cgroup_roots);  in cgroup_setup_root()
1719 	BUG_ON(atomic_read(&root->nr_cgrps) != 1);  in cgroup_setup_root()
1726 	kernfs_destroy_root(root->kf_root);  in cgroup_setup_root()
1727 	root->kf_root = NULL;  in cgroup_setup_root()
1729 	cgroup_exit_root_id(root);  in cgroup_setup_root()
1743 	struct cgroup_root *root;  in cgroup_mount()  local
1767 		root = &cgrp_dfl_root;  in cgroup_mount()
1768 		cgroup_get(&root->cgrp);  in cgroup_mount()
1782 		    ss->root == &cgrp_dfl_root)  in cgroup_mount()
1785 		if (!percpu_ref_tryget_live(&ss->root->cgrp.self.refcnt)) {  in cgroup_mount()
1791 		cgroup_put(&ss->root->cgrp);  in cgroup_mount()
1794 	for_each_root(root) {  in cgroup_mount()
1797 		if (root == &cgrp_dfl_root)  in cgroup_mount()
1806 			if (strcmp(opts.name, root->name))  in cgroup_mount()
1816 		    (opts.subsys_mask != root->subsys_mask)) {  in cgroup_mount()
1823 		if (root->flags ^ opts.flags)  in cgroup_mount()
1838 		pinned_sb = kernfs_pin_sb(root->kf_root, NULL);  in cgroup_mount()
1840 		    !percpu_ref_tryget_live(&root->cgrp.self.refcnt)) {  in cgroup_mount()
1863 	root = kzalloc(sizeof(*root), GFP_KERNEL);  in cgroup_mount()
1864 	if (!root) {  in cgroup_mount()
1869 	init_cgroup_root(root, &opts);  in cgroup_mount()
1871 	ret = cgroup_setup_root(root, opts.subsys_mask);  in cgroup_mount()
1873 		cgroup_free_root(root);  in cgroup_mount()
1884 	dentry = kernfs_mount(fs_type, flags, root->kf_root,  in cgroup_mount()
1887 		cgroup_put(&root->cgrp);  in cgroup_mount()
1904 	struct cgroup_root *root = cgroup_root_from_kf(kf_root);  in cgroup_kill_sb()  local
1913 	if (!list_empty(&root->cgrp.self.children) ||  in cgroup_kill_sb()
1914 	    root == &cgrp_dfl_root)  in cgroup_kill_sb()
1915 		cgroup_put(&root->cgrp);  in cgroup_kill_sb()
1917 		percpu_ref_kill(&root->cgrp.self.refcnt);  in cgroup_kill_sb()
1943 	struct cgroup_root *root;  in task_cgroup_path()  local
1951 	root = idr_get_next(&cgroup_hierarchy_idr, &hierarchy_id);  in task_cgroup_path()
1953 	if (root) {  in task_cgroup_path()
1954 		cgrp = task_cgroup_from_root(task, root);  in task_cgroup_path()
2127 	src_cgrp = cset_cgroup_from_root(src_cset, dst_cgrp->root);  in cgroup_migrate_add_src()
2473 	struct cgroup_root *root;  in cgroup_attach_task_all()  local
2477 	for_each_root(root) {  in cgroup_attach_task_all()
2480 		if (root == &cgrp_dfl_root)  in cgroup_attach_task_all()
2484 		from_cgrp = task_cgroup_from_root(from, root);  in cgroup_attach_task_all()
2514 	BUILD_BUG_ON(sizeof(cgrp->root->release_agent_path) < PATH_MAX);  in cgroup_release_agent_write()
2520 	strlcpy(cgrp->root->release_agent_path, strstrip(buf),  in cgroup_release_agent_write()
2521 		sizeof(cgrp->root->release_agent_path));  in cgroup_release_agent_write()
2532 	seq_puts(seq, cgrp->root->release_agent_path);  in cgroup_release_agent_show()
2567 	cgroup_print_ss_mask(seq, cgrp->root->subsys_mask &  in cgroup_root_controllers_show()
3142 	struct cgroup *root = &ss->root->cgrp;  in cgroup_apply_cftypes()  local
3149 	css_for_each_descendant_pre(css, cgroup_css(root, ss)) {  in cgroup_apply_cftypes()
3161 		kernfs_activate(root->kn);  in cgroup_apply_cftypes()
3435 			struct cgroup_subsys_state *root)  in css_next_descendant_pre()  argument
3443 		return root;  in css_next_descendant_pre()
3451 	while (pos != root) {  in css_next_descendant_pre()
3529 			 struct cgroup_subsys_state *root)  in css_next_descendant_post()  argument
3537 		return css_leftmost_descendant(root);  in css_next_descendant_post()
3540 	if (pos == root)  in css_next_descendant_post()
4391 		atomic_dec(&cgrp->root->nr_cgrps);  in css_free_work_fn()
4411 			cgroup_destroy_root(cgrp->root);  in css_free_work_fn()
4444 		cgroup_idr_remove(&cgrp->root->cgroup_idr, cgrp->id);  in css_release_work_fn()
4610 	struct cgroup_root *root;  in cgroup_mkdir()  local
4624 	root = parent->root;  in cgroup_mkdir()
4641 	cgrp->id = cgroup_idr_alloc(&root->cgroup_idr, NULL, 2, 0, GFP_NOWAIT);  in cgroup_mkdir()
4650 	cgrp->root = root;  in cgroup_mkdir()
4676 	atomic_inc(&root->nr_cgrps);  in cgroup_mkdir()
4683 	cgroup_idr_replace(&root->cgroup_idr, cgrp, cgrp->id);  in cgroup_mkdir()
4723 	cgroup_idr_remove(&root->cgroup_idr, cgrp->id);  in cgroup_mkdir()
4919 	ss->root = &cgrp_dfl_root;  in cgroup_init_subsys()
5107 	struct cgroup_root *root;  in proc_cgroup_show()  local
5117 	for_each_root(root) {  in proc_cgroup_show()
5122 		if (root == &cgrp_dfl_root && !cgrp_dfl_root_visible)  in proc_cgroup_show()
5125 		seq_printf(m, "%d:", root->hierarchy_id);  in proc_cgroup_show()
5127 			if (root->subsys_mask & (1 << ssid))  in proc_cgroup_show()
5129 		if (strlen(root->name))  in proc_cgroup_show()
5131 				   root->name);  in proc_cgroup_show()
5133 		cgrp = task_cgroup_from_root(tsk, root);  in proc_cgroup_show()
5168 			   ss->name, ss->root->hierarchy_id,  in proc_cgroupstats_show()
5169 			   atomic_read(&ss->root->nr_cgrps), !ss->disabled);  in proc_cgroupstats_show()
5359 	agentbuf = kstrdup(cgrp->root->release_agent_path, GFP_KERNEL);  in cgroup_release_agent()
5528 			   c->root->hierarchy_id, name_buf);  in current_css_set_cg_links_read()