nstree.h

 1/* SPDX-License-Identifier: GPL-2.0 */
 2/* Copyright (c) 2025 Christian Brauner <brauner@kernel.org> */
 3#ifndef _LINUX_NSTREE_H
 4#define _LINUX_NSTREE_H
 5
 6#include <linux/ns/nstree_types.h>
 7#include <linux/nsproxy.h>
 8#include <linux/rbtree.h>
 9#include <linux/seqlock.h>
10#include <linux/rculist.h>
11#include <linux/cookie.h>
12#include <uapi/linux/nsfs.h>
13
14struct ns_common;
15
16extern struct ns_tree_root cgroup_ns_tree;
17extern struct ns_tree_root ipc_ns_tree;
18extern struct ns_tree_root mnt_ns_tree;
19extern struct ns_tree_root net_ns_tree;
20extern struct ns_tree_root pid_ns_tree;
21extern struct ns_tree_root time_ns_tree;
22extern struct ns_tree_root user_ns_tree;
23extern struct ns_tree_root uts_ns_tree;
24
25void ns_tree_node_init(struct ns_tree_node *node);
26void ns_tree_root_init(struct ns_tree_root *root);
27bool ns_tree_node_empty(const struct ns_tree_node *node);
28struct rb_node *ns_tree_node_add(struct ns_tree_node *node,
29				  struct ns_tree_root *root,
30				  int (*cmp)(struct rb_node *, const struct rb_node *));
31void ns_tree_node_del(struct ns_tree_node *node, struct ns_tree_root *root);
32
33#define to_ns_tree(__ns)					\
34	_Generic((__ns),					\
35		struct cgroup_namespace *: &(cgroup_ns_tree),	\
36		struct ipc_namespace *:    &(ipc_ns_tree),	\
37		struct net *:              &(net_ns_tree),	\
38		struct pid_namespace *:    &(pid_ns_tree),	\
39		struct mnt_namespace *:    &(mnt_ns_tree),	\
40		struct time_namespace *:   &(time_ns_tree),	\
41		struct user_namespace *:   &(user_ns_tree),	\
42		struct uts_namespace *:    &(uts_ns_tree))
43
44#define ns_tree_gen_id(__ns)                 \
45	__ns_tree_gen_id(to_ns_common(__ns), \
46			 (((__ns) == ns_init_ns(__ns)) ? ns_init_id(__ns) : 0))
47
48u64 __ns_tree_gen_id(struct ns_common *ns, u64 id);
49void __ns_tree_add_raw(struct ns_common *ns, struct ns_tree_root *ns_tree);
50void __ns_tree_remove(struct ns_common *ns, struct ns_tree_root *ns_tree);
51struct ns_common *ns_tree_lookup_rcu(u64 ns_id, int ns_type);
52struct ns_common *__ns_tree_adjoined_rcu(struct ns_common *ns,
53					 struct ns_tree_root *ns_tree,
54					 bool previous);
55
56static inline void __ns_tree_add(struct ns_common *ns, struct ns_tree_root *ns_tree, u64 id)
57{
58	__ns_tree_gen_id(ns, id);
59	__ns_tree_add_raw(ns, ns_tree);
60}
61
62/**
63 * ns_tree_add_raw - Add a namespace to a namespace
64 * @ns: Namespace to add
65 *
66 * This function adds a namespace to the appropriate namespace tree
67 * without assigning a id.
68 */
69#define ns_tree_add_raw(__ns) __ns_tree_add_raw(to_ns_common(__ns), to_ns_tree(__ns))
70
71/**
72 * ns_tree_add - Add a namespace to a namespace tree
73 * @ns: Namespace to add
74 *
75 * This function assigns a new id to the namespace and adds it to the
76 * appropriate namespace tree and list.
77 */
78#define ns_tree_add(__ns)                                   \
79	__ns_tree_add(to_ns_common(__ns), to_ns_tree(__ns), \
80		      (((__ns) == ns_init_ns(__ns)) ? ns_init_id(__ns) : 0))
81
82/**
83 * ns_tree_remove - Remove a namespace from a namespace tree
84 * @ns: Namespace to remove
85 *
86 * This function removes a namespace from the appropriate namespace
87 * tree and list.
88 */
89#define ns_tree_remove(__ns)  __ns_tree_remove(to_ns_common(__ns), to_ns_tree(__ns))
90
91#define ns_tree_adjoined_rcu(__ns, __previous) \
92	__ns_tree_adjoined_rcu(to_ns_common(__ns), to_ns_tree(__ns), __previous)
93
94#define ns_tree_active(__ns) (!RB_EMPTY_NODE(&to_ns_common(__ns)->ns_tree_node.ns_node))
95
96#endif /* _LINUX_NSTREE_H */