ab516013ad
This patch adds a nsproxy structure to the task struct. Later patches will move the fs namespace pointer into this structure, and introduce a new utsname namespace into the nsproxy. The vserver and openvz functionality, then, would be implemented in large part by virtualizing/isolating more and more resources into namespaces, each contained in the nsproxy. [akpm@osdl.org: build fix] Signed-off-by: Serge Hallyn <serue@us.ibm.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Andrey Savochkin <saw@sw.ru> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
46 lines
1.1 KiB
C
46 lines
1.1 KiB
C
#ifndef _LINUX_NSPROXY_H
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#define _LINUX_NSPROXY_H
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#include <linux/spinlock.h>
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#include <linux/sched.h>
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/*
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* A structure to contain pointers to all per-process
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* namespaces - fs (mount), uts, network, sysvipc, etc.
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*
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* 'count' is the number of tasks holding a reference.
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* The count for each namespace, then, will be the number
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* of nsproxies pointing to it, not the number of tasks.
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*
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* The nsproxy is shared by tasks which share all namespaces.
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* As soon as a single namespace is cloned or unshared, the
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* nsproxy is copied.
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*/
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struct nsproxy {
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atomic_t count;
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spinlock_t nslock;
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};
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extern struct nsproxy init_nsproxy;
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struct nsproxy *dup_namespaces(struct nsproxy *orig);
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int copy_namespaces(int flags, struct task_struct *tsk);
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void get_task_namespaces(struct task_struct *tsk);
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void free_nsproxy(struct nsproxy *ns);
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static inline void put_nsproxy(struct nsproxy *ns)
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{
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if (atomic_dec_and_test(&ns->count)) {
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free_nsproxy(ns);
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}
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}
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static inline void exit_task_namespaces(struct task_struct *p)
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{
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struct nsproxy *ns = p->nsproxy;
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if (ns) {
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put_nsproxy(ns);
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p->nsproxy = NULL;
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}
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}
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#endif
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