#ifndef _LINUX_PID_NS_H
#define _LINUX_PID_NS_H

#include <linux/sched.h>
#include <linux/bug.h>
#include <linux/mm.h>
#include <linux/workqueue.h>
#include <linux/threads.h>
#include <linux/nsproxy.h>
#include <linux/kref.h>

struct pidmap {
atomic_t nr_free;
void *page;
};

#define BITS_PER_PAGE (PAGE_SIZE * 8)
#define BITS_PER_PAGE_MASK (BITS_PER_PAGE-1)
#define PIDMAP_ENTRIES ((PID_MAX_LIMIT+BITS_PER_PAGE-1)/BITS_PER_PAGE)

struct bsd_acct_struct;

struct pid_namespace {
struct kref kref;
struct pidmap pidmap[PIDMAP_ENTRIES];
struct rcu_head rcu;
int last_pid;
unsigned int nr_hashed;
struct task_struct *child_reaper;
struct kmem_cache *pid_cachep;
unsigned int level;
struct pid_namespace *parent;
#ifdef CONFIG_PROC_FS
struct vfsmount *proc_mnt;
struct dentry *proc_self;
#endif
#ifdef CONFIG_BSD_PROCESS_ACCT
struct bsd_acct_struct *bacct;
#endif
struct user_namespace *user_ns;
struct work_struct proc_work;
kgid_t pid_gid;
int hide_pid;
int reboot; /* group exit code if this pidns was rebooted */
unsigned int proc_inum;
};

extern struct pid_namespace init_pid_ns;

#define PIDNS_HASH_ADDING (1U << 31)

#ifdef CONFIG_PID_NS
static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
{
if (ns != &init_pid_ns)
kref_get(&ns->kref);
return ns;
}

extern struct pid_namespace *copy_pid_ns(unsigned long flags,
struct user_namespace *user_ns, struct pid_namespace *ns);
extern void zap_pid_ns_processes(struct pid_namespace *pid_ns);
extern int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd);
extern void put_pid_ns(struct pid_namespace *ns);

#else /* !CONFIG_PID_NS */
#include <linux/err.h>

static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
{
return ns;
}

static inline struct pid_namespace *copy_pid_ns(unsigned long flags,
struct user_namespace *user_ns, struct pid_namespace *ns)
{
if (flags & CLONE_NEWPID)
ns = ERR_PTR(-EINVAL);
return ns;
}

static inline void put_pid_ns(struct pid_namespace *ns)
{
}

static inline void zap_pid_ns_processes(struct pid_namespace *ns)
{
BUG();
}

static inline int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd)
{
return 0;
}
#endif /* CONFIG_PID_NS */

extern struct pid_namespace *task_active_pid_ns(struct task_struct *tsk);
void pidhash_init(void);
void pidmap_init(void);

#endif /* _LINUX_PID_NS_H */