root/include/linux/pid_namespace.h

INCLUDED FROM

DEFINITIONS

1. get_pid_ns
2. get_pid_ns
3. copy_pid_ns
4. put_pid_ns
5. zap_pid_ns_processes
6. reboot_pid_ns

#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;
        struct dentry *proc_thread_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 */