linux_old1/include/linux/nsproxy.h

59 lines
1.4 KiB
C

#ifndef _LINUX_NSPROXY_H
#define _LINUX_NSPROXY_H
#include <linux/spinlock.h>
#include <linux/sched.h>
struct mnt_namespace;
struct uts_namespace;
struct ipc_namespace;
struct pid_namespace;
/*
* A structure to contain pointers to all per-process
* namespaces - fs (mount), uts, network, sysvipc, etc.
*
* 'count' is the number of tasks holding a reference.
* The count for each namespace, then, will be the number
* of nsproxies pointing to it, not the number of tasks.
*
* The nsproxy is shared by tasks which share all namespaces.
* As soon as a single namespace is cloned or unshared, the
* nsproxy is copied.
*/
struct nsproxy {
atomic_t count;
spinlock_t nslock;
struct uts_namespace *uts_ns;
struct ipc_namespace *ipc_ns;
struct mnt_namespace *mnt_ns;
struct pid_namespace *pid_ns;
struct user_namespace *user_ns;
};
extern struct nsproxy init_nsproxy;
int copy_namespaces(unsigned long flags, struct task_struct *tsk);
void get_task_namespaces(struct task_struct *tsk);
void free_nsproxy(struct nsproxy *ns);
int unshare_nsproxy_namespaces(unsigned long, struct nsproxy **,
struct fs_struct *);
static inline void put_nsproxy(struct nsproxy *ns)
{
if (atomic_dec_and_test(&ns->count)) {
free_nsproxy(ns);
}
}
static inline void exit_task_namespaces(struct task_struct *p)
{
struct nsproxy *ns = p->nsproxy;
if (ns) {
task_lock(p);
p->nsproxy = NULL;
task_unlock(p);
put_nsproxy(ns);
}
}
#endif