LXR linux/include/linux/pid

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _LINUX_PID_NS_H
   3#define _LINUX_PID_NS_H
   4
   5#include <linux/sched.h>
   6#include <linux/bug.h>
   7#include <linux/mm.h>
   8#include <linux/workqueue.h>
   9#include <linux/threads.h>
  10#include <linux/nsproxy.h>
  11#include <linux/ns_common.h>
  12#include <linux/idr.h>
  13
  14/* MAX_PID_NS_LEVEL is needed for limiting size of 'struct pid' */
  15#define MAX_PID_NS_LEVEL 32
  16
  17struct fs_pin;
  18
  19struct pid_namespace {
  20        struct idr idr;
  21        struct rcu_head rcu;
  22        unsigned int pid_allocated;
  23        struct task_struct *child_reaper;
  24        struct kmem_cache *pid_cachep;
  25        unsigned int level;
  26        struct pid_namespace *parent;
  27#ifdef CONFIG_BSD_PROCESS_ACCT
  28        struct fs_pin *bacct;
  29#endif
  30        struct user_namespace *user_ns;
  31        struct ucounts *ucounts;
  32        int reboot;     /* group exit code if this pidns was rebooted */
  33        struct ns_common ns;
  34} __randomize_layout;
  35
  36extern struct pid_namespace init_pid_ns;
  37
  38#define PIDNS_ADDING (1U << 31)
  39
  40#ifdef CONFIG_PID_NS
  41static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
  42{
  43        if (ns != &init_pid_ns)
  44                refcount_inc(&ns->ns.count);
  45        return ns;
  46}
  47
  48extern struct pid_namespace *copy_pid_ns(unsigned long flags,
  49        struct user_namespace *user_ns, struct pid_namespace *ns);
  50extern void zap_pid_ns_processes(struct pid_namespace *pid_ns);
  51extern int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd);
  52extern void put_pid_ns(struct pid_namespace *ns);
  53
  54#else /* !CONFIG_PID_NS */
  55#include <linux/err.h>
  56
  57static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
  58{
  59        return ns;
  60}
  61
  62static inline struct pid_namespace *copy_pid_ns(unsigned long flags,
  63        struct user_namespace *user_ns, struct pid_namespace *ns)
  64{
  65        if (flags & CLONE_NEWPID)
  66                ns = ERR_PTR(-EINVAL);
  67        return ns;
  68}
  69
  70static inline void put_pid_ns(struct pid_namespace *ns)
  71{
  72}
  73
  74static inline void zap_pid_ns_processes(struct pid_namespace *ns)
  75{
  76        BUG();
  77}
  78
  79static inline int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd)
  80{
  81        return 0;
  82}
  83#endif /* CONFIG_PID_NS */
  84
  85extern struct pid_namespace *task_active_pid_ns(struct task_struct *tsk);
  86void pidhash_init(void);
  87void pid_idr_init(void);
  88
  89static inline bool task_is_in_init_pid_ns(struct task_struct *tsk)
  90{
  91        return task_active_pid_ns(tsk) == &init_pid_ns;
  92}
  93
  94#endif /* _LINUX_PID_NS_H */
  95