Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751025AbWERPsx (ORCPT ); Thu, 18 May 2006 11:48:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751096AbWERPsx (ORCPT ); Thu, 18 May 2006 11:48:53 -0400 Received: from e31.co.us.ibm.com ([32.97.110.149]:47556 "EHLO e31.co.us.ibm.com") by vger.kernel.org with ESMTP id S1751025AbWERPsw (ORCPT ); Thu, 18 May 2006 11:48:52 -0400 Date: Thu, 18 May 2006 10:48:37 -0500 From: "Serge E. Hallyn" To: linux-kernel@vger.kernel.org Cc: dev@sw.ru, herbert@13thfloor.at, devel@openvz.org, sam@vilain.net, ebiederm@xmission.com, xemul@sw.ru, Dave Hansen , Andrew Morton , Cedric Le Goater Subject: [PATCH 1/9] namespaces: add nsproxy Message-ID: <20060518154837.GB28344@sergelap.austin.ibm.com> References: <20060518154700.GA28344@sergelap.austin.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060518154700.GA28344@sergelap.austin.ibm.com> User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 24096 Lines: 747 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. Signed-off-by: Serge Hallyn --- arch/alpha/kernel/init_task.c | 2 + arch/arm/kernel/init_task.c | 2 + arch/arm26/kernel/init_task.c | 2 + arch/frv/kernel/init_task.c | 2 + arch/h8300/kernel/init_task.c | 2 + arch/i386/kernel/init_task.c | 2 + arch/ia64/kernel/init_task.c | 2 + arch/m32r/kernel/init_task.c | 2 + arch/m68knommu/kernel/init_task.c | 2 + arch/mips/kernel/init_task.c | 2 + arch/parisc/kernel/init_task.c | 2 + arch/powerpc/kernel/init_task.c | 2 + arch/s390/kernel/init_task.c | 2 + arch/sh/kernel/init_task.c | 2 + arch/sh64/kernel/init_task.c | 2 + arch/sparc/kernel/init_task.c | 2 + arch/sparc64/kernel/init_task.c | 2 + arch/um/kernel/init_task.c | 2 + arch/v850/kernel/init_task.c | 2 + arch/x86_64/kernel/init_task.c | 2 + include/linux/init_task.h | 7 +++ include/linux/nsproxy.h | 45 +++++++++++++++++++++ include/linux/sched.h | 2 + kernel/Makefile | 2 - kernel/exit.c | 7 +++ kernel/fork.c | 18 ++++++++- kernel/nsproxy.c | 78 +++++++++++++++++++++++++++++++++++++ 27 files changed, 197 insertions(+), 2 deletions(-) create mode 100644 include/linux/nsproxy.h create mode 100644 kernel/nsproxy.c 7c65cea6d1931f03867fad978f33072a4b0a4602 diff --git a/arch/alpha/kernel/init_task.c b/arch/alpha/kernel/init_task.c index 835d09a..83d0902 100644 --- a/arch/alpha/kernel/init_task.c +++ b/arch/alpha/kernel/init_task.c @@ -5,6 +5,7 @@ #include #include #include +#include #include @@ -13,6 +14,7 @@ static struct files_struct init_files = static struct signal_struct init_signals = INIT_SIGNALS(init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); struct mm_struct init_mm = INIT_MM(init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); struct task_struct init_task = INIT_TASK(init_task); EXPORT_SYMBOL(init_mm); diff --git a/arch/arm/kernel/init_task.c b/arch/arm/kernel/init_task.c index a00cca0..80f5eeb 100644 --- a/arch/arm/kernel/init_task.c +++ b/arch/arm/kernel/init_task.c @@ -8,6 +8,7 @@ #include #include #include +#include #include #include @@ -17,6 +18,7 @@ static struct files_struct init_files = static struct signal_struct init_signals = INIT_SIGNALS(init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); struct mm_struct init_mm = INIT_MM(init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); EXPORT_SYMBOL(init_mm); diff --git a/arch/arm26/kernel/init_task.c b/arch/arm26/kernel/init_task.c index 4191565..678c7b5 100644 --- a/arch/arm26/kernel/init_task.c +++ b/arch/arm26/kernel/init_task.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include @@ -20,6 +21,7 @@ static struct files_struct init_files = static struct signal_struct init_signals = INIT_SIGNALS(init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); struct mm_struct init_mm = INIT_MM(init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); EXPORT_SYMBOL(init_mm); diff --git a/arch/frv/kernel/init_task.c b/arch/frv/kernel/init_task.c index 2299393..5ec2742 100644 --- a/arch/frv/kernel/init_task.c +++ b/arch/frv/kernel/init_task.c @@ -5,6 +5,7 @@ #include #include #include +#include #include #include @@ -15,6 +16,7 @@ static struct files_struct init_files = static struct signal_struct init_signals = INIT_SIGNALS(init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); struct mm_struct init_mm = INIT_MM(init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); EXPORT_SYMBOL(init_mm); diff --git a/arch/h8300/kernel/init_task.c b/arch/h8300/kernel/init_task.c index 19272c2..ef5755a 100644 --- a/arch/h8300/kernel/init_task.c +++ b/arch/h8300/kernel/init_task.c @@ -8,6 +8,7 @@ #include #include #include +#include #include #include @@ -17,6 +18,7 @@ static struct files_struct init_files = static struct signal_struct init_signals = INIT_SIGNALS(init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); struct mm_struct init_mm = INIT_MM(init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); EXPORT_SYMBOL(init_mm); diff --git a/arch/i386/kernel/init_task.c b/arch/i386/kernel/init_task.c index cff95d1..bd97f69 100644 --- a/arch/i386/kernel/init_task.c +++ b/arch/i386/kernel/init_task.c @@ -5,6 +5,7 @@ #include #include #include +#include #include #include @@ -15,6 +16,7 @@ static struct files_struct init_files = static struct signal_struct init_signals = INIT_SIGNALS(init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); struct mm_struct init_mm = INIT_MM(init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); EXPORT_SYMBOL(init_mm); diff --git a/arch/ia64/kernel/init_task.c b/arch/ia64/kernel/init_task.c index b69c397..2d62471 100644 --- a/arch/ia64/kernel/init_task.c +++ b/arch/ia64/kernel/init_task.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include @@ -21,6 +22,7 @@ static struct files_struct init_files = static struct signal_struct init_signals = INIT_SIGNALS(init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); struct mm_struct init_mm = INIT_MM(init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); EXPORT_SYMBOL(init_mm); diff --git a/arch/m32r/kernel/init_task.c b/arch/m32r/kernel/init_task.c index 9e508fd..0057475 100644 --- a/arch/m32r/kernel/init_task.c +++ b/arch/m32r/kernel/init_task.c @@ -7,6 +7,7 @@ #include #include #include +#include #include #include @@ -16,6 +17,7 @@ static struct files_struct init_files = static struct signal_struct init_signals = INIT_SIGNALS(init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); struct mm_struct init_mm = INIT_MM(init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); EXPORT_SYMBOL(init_mm); diff --git a/arch/m68knommu/kernel/init_task.c b/arch/m68knommu/kernel/init_task.c index 3897043..b99fc6d 100644 --- a/arch/m68knommu/kernel/init_task.c +++ b/arch/m68knommu/kernel/init_task.c @@ -8,6 +8,7 @@ #include #include #include +#include #include #include @@ -17,6 +18,7 @@ static struct files_struct init_files = static struct signal_struct init_signals = INIT_SIGNALS(init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); struct mm_struct init_mm = INIT_MM(init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); EXPORT_SYMBOL(init_mm); diff --git a/arch/mips/kernel/init_task.c b/arch/mips/kernel/init_task.c index aeda7f5..dfe47e6 100644 --- a/arch/mips/kernel/init_task.c +++ b/arch/mips/kernel/init_task.c @@ -4,6 +4,7 @@ #include #include #include +#include #include #include @@ -14,6 +15,7 @@ static struct files_struct init_files = static struct signal_struct init_signals = INIT_SIGNALS(init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); struct mm_struct init_mm = INIT_MM(init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); EXPORT_SYMBOL(init_mm); diff --git a/arch/parisc/kernel/init_task.c b/arch/parisc/kernel/init_task.c index 8384bf9..c0c43e2 100644 --- a/arch/parisc/kernel/init_task.c +++ b/arch/parisc/kernel/init_task.c @@ -28,6 +28,7 @@ #include #include #include +#include #include #include @@ -38,6 +39,7 @@ static struct files_struct init_files = static struct signal_struct init_signals = INIT_SIGNALS(init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); struct mm_struct init_mm = INIT_MM(init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); EXPORT_SYMBOL(init_mm); diff --git a/arch/powerpc/kernel/init_task.c b/arch/powerpc/kernel/init_task.c index 941043a..e24ace6 100644 --- a/arch/powerpc/kernel/init_task.c +++ b/arch/powerpc/kernel/init_task.c @@ -5,6 +5,7 @@ #include #include #include +#include #include static struct fs_struct init_fs = INIT_FS; @@ -12,6 +13,7 @@ static struct files_struct init_files = static struct signal_struct init_signals = INIT_SIGNALS(init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); struct mm_struct init_mm = INIT_MM(init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); EXPORT_SYMBOL(init_mm); diff --git a/arch/s390/kernel/init_task.c b/arch/s390/kernel/init_task.c index d73a740..0918921 100644 --- a/arch/s390/kernel/init_task.c +++ b/arch/s390/kernel/init_task.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include @@ -20,6 +21,7 @@ static struct files_struct init_files = static struct signal_struct init_signals = INIT_SIGNALS(init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); struct mm_struct init_mm = INIT_MM(init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); EXPORT_SYMBOL(init_mm); diff --git a/arch/sh/kernel/init_task.c b/arch/sh/kernel/init_task.c index 44053ea..81caf0f 100644 --- a/arch/sh/kernel/init_task.c +++ b/arch/sh/kernel/init_task.c @@ -3,6 +3,7 @@ #include #include #include +#include #include #include @@ -12,6 +13,7 @@ static struct files_struct init_files = static struct signal_struct init_signals = INIT_SIGNALS(init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); struct mm_struct init_mm = INIT_MM(init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); EXPORT_SYMBOL(init_mm); diff --git a/arch/sh64/kernel/init_task.c b/arch/sh64/kernel/init_task.c index de2d07d..0c95f40 100644 --- a/arch/sh64/kernel/init_task.c +++ b/arch/sh64/kernel/init_task.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include @@ -23,6 +24,7 @@ static struct files_struct init_files = static struct signal_struct init_signals = INIT_SIGNALS(init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); struct mm_struct init_mm = INIT_MM(init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); struct pt_regs fake_swapper_regs; diff --git a/arch/sparc/kernel/init_task.c b/arch/sparc/kernel/init_task.c index fc31de6..a73926d 100644 --- a/arch/sparc/kernel/init_task.c +++ b/arch/sparc/kernel/init_task.c @@ -3,6 +3,7 @@ #include #include #include +#include #include #include @@ -12,6 +13,7 @@ static struct files_struct init_files = static struct signal_struct init_signals = INIT_SIGNALS(init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); struct mm_struct init_mm = INIT_MM(init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); struct task_struct init_task = INIT_TASK(init_task); EXPORT_SYMBOL(init_mm); diff --git a/arch/sparc64/kernel/init_task.c b/arch/sparc64/kernel/init_task.c index 329b38f..f1e9a4b 100644 --- a/arch/sparc64/kernel/init_task.c +++ b/arch/sparc64/kernel/init_task.c @@ -3,6 +3,7 @@ #include #include #include +#include #include #include @@ -13,6 +14,7 @@ static struct files_struct init_files = static struct signal_struct init_signals = INIT_SIGNALS(init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); struct mm_struct init_mm = INIT_MM(init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); EXPORT_SYMBOL(init_mm); diff --git a/arch/um/kernel/init_task.c b/arch/um/kernel/init_task.c index 49ed5dd..11188af 100644 --- a/arch/um/kernel/init_task.c +++ b/arch/um/kernel/init_task.c @@ -9,6 +9,7 @@ #include "linux/sched.h" #include "linux/init_task.h" #include "linux/mqueue.h" +#include "linux/nsproxy.h" #include "asm/uaccess.h" #include "asm/pgtable.h" #include "user_util.h" @@ -17,6 +18,7 @@ static struct fs_struct init_fs = INIT_FS; struct mm_struct init_mm = INIT_MM(init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); static struct files_struct init_files = INIT_FILES; static struct signal_struct init_signals = INIT_SIGNALS(init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); diff --git a/arch/v850/kernel/init_task.c b/arch/v850/kernel/init_task.c index ed2f93c..9d2de75 100644 --- a/arch/v850/kernel/init_task.c +++ b/arch/v850/kernel/init_task.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include @@ -25,6 +26,7 @@ static struct files_struct init_files = static struct signal_struct init_signals = INIT_SIGNALS (init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); struct mm_struct init_mm = INIT_MM (init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); EXPORT_SYMBOL(init_mm); diff --git a/arch/x86_64/kernel/init_task.c b/arch/x86_64/kernel/init_task.c index ce31d90..1c87ea0 100644 --- a/arch/x86_64/kernel/init_task.c +++ b/arch/x86_64/kernel/init_task.c @@ -5,6 +5,7 @@ #include #include #include +#include #include #include @@ -15,6 +16,7 @@ static struct files_struct init_files = static struct signal_struct init_signals = INIT_SIGNALS(init_signals); static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); struct mm_struct init_mm = INIT_MM(init_mm); +struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); EXPORT_SYMBOL(init_mm); diff --git a/include/linux/init_task.h b/include/linux/init_task.h index 41ecbb8..79ec4ea 100644 --- a/include/linux/init_task.h +++ b/include/linux/init_task.h @@ -66,6 +66,12 @@ .session = 1, \ } +extern struct nsproxy init_nsproxy; +#define INIT_NSPROXY(nsproxy) { \ + .count = ATOMIC_INIT(1), \ + .nslock = SPIN_LOCK_UNLOCKED, \ +} + #define INIT_SIGHAND(sighand) { \ .count = ATOMIC_INIT(1), \ .action = { { { .sa_handler = NULL, } }, }, \ @@ -114,6 +120,7 @@ extern struct group_info init_groups; .files = &init_files, \ .signal = &init_signals, \ .sighand = &init_sighand, \ + .nsproxy = &init_nsproxy, \ .pending = { \ .list = LIST_HEAD_INIT(tsk.pending.list), \ .signal = {{0}}}, \ diff --git a/include/linux/nsproxy.h b/include/linux/nsproxy.h new file mode 100644 index 0000000..7bdebfa --- /dev/null +++ b/include/linux/nsproxy.h @@ -0,0 +1,45 @@ +#ifndef _LINUX_NSPROXY_H +#define _LINUX_NSPROXY_H + +#include +#include + +/* + * 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; +}; +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) { + put_nsproxy(ns); + p->nsproxy = NULL; + } +} +#endif diff --git a/include/linux/sched.h b/include/linux/sched.h index 29b7d4f..4c0bbb3 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -236,6 +236,7 @@ extern signed long schedule_timeout_unin asmlinkage void schedule(void); struct namespace; +struct nsproxy; /* Maximum number of active map areas.. This is a random (large) number */ #define DEFAULT_MAX_MAP_COUNT 65536 @@ -808,6 +809,7 @@ struct task_struct { struct files_struct *files; /* namespace */ struct namespace *namespace; + struct nsproxy *nsproxy; /* signal handlers */ struct signal_struct *signal; struct sighand_struct *sighand; diff --git a/kernel/Makefile b/kernel/Makefile index 58908f9..215fb33 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -8,7 +8,7 @@ obj-y = sched.o fork.o exec_domain.o signal.o sys.o kmod.o workqueue.o pid.o \ rcupdate.o extable.o params.o posix-timers.o \ kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o \ - hrtimer.o + hrtimer.o nsproxy.o obj-$(CONFIG_DEBUG_MUTEXES) += mutex-debug.o obj-$(CONFIG_FUTEX) += futex.o diff --git a/kernel/exit.c b/kernel/exit.c index e95b932..da2fc84 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -36,6 +36,7 @@ #include #include #include /* for audit_free() */ +#include #include #include @@ -413,9 +414,14 @@ void daemonize(const char *name, ...) fs = init_task.fs; current->fs = fs; atomic_inc(&fs->count); + exit_namespace(current); + exit_task_namespaces(current); current->namespace = init_task.namespace; + current->nsproxy = init_task.nsproxy; get_namespace(current->namespace); + get_task_namespaces(current); + exit_files(current); current->files = init_task.files; atomic_inc(¤t->files->count); @@ -919,6 +925,7 @@ fastcall NORET_TYPE void do_exit(long co __exit_files(tsk); __exit_fs(tsk); exit_namespace(tsk); + exit_task_namespaces(tsk); exit_thread(); cpuset_exit(tsk); exit_keys(tsk); diff --git a/kernel/fork.c b/kernel/fork.c index ac8100e..60303c3 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -44,6 +44,7 @@ #include #include #include +#include #include #include @@ -1060,8 +1061,10 @@ static task_t *copy_process(unsigned lon goto bad_fork_cleanup_signal; if ((retval = copy_keys(clone_flags, p))) goto bad_fork_cleanup_mm; - if ((retval = copy_namespace(clone_flags, p))) + if ((retval = copy_namespaces(clone_flags, p))) goto bad_fork_cleanup_keys; + if ((retval = copy_namespace(clone_flags, p))) + goto bad_fork_cleanup_namespaces; retval = copy_thread(0, clone_flags, stack_start, stack_size, p, regs); if (retval) goto bad_fork_cleanup_namespace; @@ -1218,6 +1221,8 @@ static task_t *copy_process(unsigned lon bad_fork_cleanup_namespace: exit_namespace(p); +bad_fork_cleanup_namespaces: + exit_task_namespaces(p); bad_fork_cleanup_keys: exit_keys(p); bad_fork_cleanup_mm: @@ -1559,6 +1564,7 @@ asmlinkage long sys_unshare(unsigned lon struct mm_struct *mm, *new_mm = NULL, *active_mm = NULL; struct files_struct *fd, *new_fd = NULL; struct sem_undo_list *new_ulist = NULL; + struct nsproxy *new_nsproxy, *old_nsproxy; check_unshare_flags(&unshare_flags); @@ -1585,7 +1591,15 @@ asmlinkage long sys_unshare(unsigned lon if (new_fs || new_ns || new_sigh || new_mm || new_fd || new_ulist) { + old_nsproxy = current->nsproxy; + new_nsproxy = dup_namespaces(old_nsproxy); + if (!new_nsproxy) { + err = -ENOMEM; + goto bad_unshare_cleanup_semundo; + } + task_lock(current); + current->nsproxy = new_nsproxy; if (new_fs) { fs = current->fs; @@ -1621,8 +1635,10 @@ asmlinkage long sys_unshare(unsigned lon } task_unlock(current); + put_nsproxy(old_nsproxy); } +bad_unshare_cleanup_semundo: bad_unshare_cleanup_fd: if (new_fd) put_files_struct(new_fd); diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c new file mode 100644 index 0000000..6f53df1 --- /dev/null +++ b/kernel/nsproxy.c @@ -0,0 +1,78 @@ +/* + * Copyright (C) 2006 IBM Corporation + * + * Author: Serge Hallyn + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + */ + +#include +#include +#include +#include + +static inline void get_nsproxy(struct nsproxy *ns) +{ + atomic_inc(&ns->count); +} + +void get_task_namespaces(struct task_struct *tsk) +{ + struct nsproxy *ns = tsk->nsproxy; + if (ns) { + get_nsproxy(ns); + } +} + +/* + * creates a copy of "orig" with refcount 1. + * This does not grab references to the contained namespaces, + * so that needs to be done by dup_namespaces. + */ +static inline struct nsproxy *clone_namespaces(struct nsproxy *orig) +{ + struct nsproxy *ns; + + ns = kmalloc(sizeof(struct nsproxy), GFP_KERNEL); + if (ns) { + memcpy(ns, orig, sizeof(struct nsproxy)); + atomic_set(&ns->count, 1); + } + return ns; +} + +/* + * copies the nsproxy, setting refcount to 1, and grabbing a + * reference to all contained namespaces. Called from + * sys_unshare() + */ +struct nsproxy *dup_namespaces(struct nsproxy *orig) +{ + struct nsproxy *ns = clone_namespaces(orig); + + return ns; +} + +/* + * called from clone. This now handles copy for nsproxy and all + * namespaces therein. + */ +int copy_namespaces(int flags, struct task_struct *tsk) +{ + struct nsproxy *old_ns = tsk->nsproxy; + + if (!old_ns) + return 0; + + get_nsproxy(old_ns); + + return 0; +} + +void free_nsproxy(struct nsproxy *ns) +{ + kfree(ns); +} -- 1.1.6 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/