#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; }; extern struct nsproxy init_nsproxy; struct nsproxy *dup_namespaces(struct nsproxy *orig); int copy_namespaces(int flags, struct task_struct *tsk); void get_task_namespaces(struct task_struct *tsk); void free_nsproxy(struct nsproxy *ns); 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