namespaces: move the IPC namespace under IPC_NS option

Currently the IPC namespace management code is spread over the ipc/*.c files.
I moved this code into ipc/namespace.c file which is compiled out when needed.

The linux/ipc_namespace.h file is used to store the prototypes of the
functions in namespace.c and the stubs for NAMESPACES=n case.  This is done
so, because the stub for copy_ipc_namespace requires the knowledge of the
CLONE_NEWIPC flag, which is in sched.h.  But the linux/ipc.h file itself in
included into many many .c files via the sys.h->sem.h sequence so adding the
sched.h into it will make all these .c depend on sched.h which is not that
good.  On the other hand the knowledge about the namespaces stuff is required
in 4 .c files only.

Besides, this patch compiles out some auxiliary functions from ipc/sem.c,
msg.c and shm.c files.  It turned out that moving these functions into
namespaces.c is not that easy because they use many other calls and macros
from the original file.  Moving them would make this patch complicated.  On
the other hand all these functions can be consolidated, so I will send a
separate patch doing this a bit later.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Kirill Korotaev <dev@sw.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Pavel Emelyanov 2008-02-08 04:18:22 -08:00 committed by Linus Torvalds
parent 58bfdd6dee
commit ae5e1b22f1
12 changed files with 164 additions and 112 deletions

View file

@ -100,58 +100,6 @@ struct kern_ipc_perm
void *security;
};
struct ipc_ids;
struct ipc_namespace {
struct kref kref;
struct ipc_ids *ids[3];
int sem_ctls[4];
int used_sems;
int msg_ctlmax;
int msg_ctlmnb;
int msg_ctlmni;
atomic_t msg_bytes;
atomic_t msg_hdrs;
size_t shm_ctlmax;
size_t shm_ctlall;
int shm_ctlmni;
int shm_tot;
};
extern struct ipc_namespace init_ipc_ns;
#ifdef CONFIG_SYSVIPC
#define INIT_IPC_NS(ns) .ns = &init_ipc_ns,
extern void free_ipc_ns(struct kref *kref);
extern struct ipc_namespace *copy_ipcs(unsigned long flags,
struct ipc_namespace *ns);
#else
#define INIT_IPC_NS(ns)
static inline struct ipc_namespace *copy_ipcs(unsigned long flags,
struct ipc_namespace *ns)
{
return ns;
}
#endif
static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
{
#ifdef CONFIG_SYSVIPC
if (ns)
kref_get(&ns->kref);
#endif
return ns;
}
static inline void put_ipc_ns(struct ipc_namespace *ns)
{
#ifdef CONFIG_SYSVIPC
kref_put(&ns->kref, free_ipc_ns);
#endif
}
#endif /* __KERNEL__ */
#endif /* _LINUX_IPC_H */

View file

@ -0,0 +1,69 @@
#ifndef __IPC_NAMESPACE_H__
#define __IPC_NAMESPACE_H__
#include <linux/err.h>
struct ipc_ids;
struct ipc_namespace {
struct kref kref;
struct ipc_ids *ids[3];
int sem_ctls[4];
int used_sems;
int msg_ctlmax;
int msg_ctlmnb;
int msg_ctlmni;
atomic_t msg_bytes;
atomic_t msg_hdrs;
size_t shm_ctlmax;
size_t shm_ctlall;
int shm_ctlmni;
int shm_tot;
};
extern struct ipc_namespace init_ipc_ns;
#ifdef CONFIG_SYSVIPC
#define INIT_IPC_NS(ns) .ns = &init_ipc_ns,
#else
#define INIT_IPC_NS(ns)
#endif
#if defined(CONFIG_SYSVIPC) && defined(CONFIG_IPC_NS)
extern void free_ipc_ns(struct kref *kref);
extern struct ipc_namespace *copy_ipcs(unsigned long flags,
struct ipc_namespace *ns);
static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
{
if (ns)
kref_get(&ns->kref);
return ns;
}
static inline void put_ipc_ns(struct ipc_namespace *ns)
{
kref_put(&ns->kref, free_ipc_ns);
}
#else
static inline struct ipc_namespace *copy_ipcs(unsigned long flags,
struct ipc_namespace *ns)
{
if (flags & CLONE_NEWIPC)
return ERR_PTR(-EINVAL);
return ns;
}
static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
{
return ns;
}
static inline void put_ipc_ns(struct ipc_namespace *ns)
{
}
#endif
#endif

View file

@ -436,6 +436,13 @@ config UTS_NS
In this namespace tasks see different info provided with the
uname() system call
config IPC_NS
bool "IPC namespace"
depends on NAMESPACES && SYSVIPC
help
In this namespace tasks work with IPC ids which correspond to
different IPC objects in different namespaces
config BLK_DEV_INITRD
bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
depends on BROKEN || !FRV

View file

@ -7,4 +7,5 @@ obj-$(CONFIG_SYSVIPC) += util.o msgutil.o msg.o sem.o shm.o
obj-$(CONFIG_SYSVIPC_SYSCTL) += ipc_sysctl.o
obj_mq-$(CONFIG_COMPAT) += compat_mq.o
obj-$(CONFIG_POSIX_MQUEUE) += mqueue.o msgutil.o $(obj_mq-y)
obj-$(CONFIG_IPC_NS) += namespace.o

View file

@ -14,6 +14,7 @@
#include <linux/nsproxy.h>
#include <linux/sysctl.h>
#include <linux/uaccess.h>
#include <linux/ipc_namespace.h>
static void *get_ipc(ctl_table *table)
{

View file

@ -36,6 +36,7 @@
#include <linux/seq_file.h>
#include <linux/rwsem.h>
#include <linux/nsproxy.h>
#include <linux/ipc_namespace.h>
#include <asm/current.h>
#include <asm/uaccess.h>
@ -90,6 +91,7 @@ static void __msg_init_ns(struct ipc_namespace *ns, struct ipc_ids *ids)
ipc_init_ids(ids);
}
#ifdef CONFIG_IPC_NS
int msg_init_ns(struct ipc_namespace *ns)
{
struct ipc_ids *ids;
@ -128,6 +130,7 @@ void msg_exit_ns(struct ipc_namespace *ns)
kfree(ns->ids[IPC_MSG_IDS]);
ns->ids[IPC_MSG_IDS] = NULL;
}
#endif
void __init msg_init(void)
{

73
ipc/namespace.c Normal file
View file

@ -0,0 +1,73 @@
/*
* linux/ipc/namespace.c
* Copyright (C) 2006 Pavel Emelyanov <xemul@openvz.org> OpenVZ, SWsoft Inc.
*/
#include <linux/ipc.h>
#include <linux/msg.h>
#include <linux/ipc_namespace.h>
#include <linux/rcupdate.h>
#include <linux/nsproxy.h>
#include <linux/slab.h>
#include "util.h"
static struct ipc_namespace *clone_ipc_ns(struct ipc_namespace *old_ns)
{
int err;
struct ipc_namespace *ns;
err = -ENOMEM;
ns = kmalloc(sizeof(struct ipc_namespace), GFP_KERNEL);
if (ns == NULL)
goto err_mem;
err = sem_init_ns(ns);
if (err)
goto err_sem;
err = msg_init_ns(ns);
if (err)
goto err_msg;
err = shm_init_ns(ns);
if (err)
goto err_shm;
kref_init(&ns->kref);
return ns;
err_shm:
msg_exit_ns(ns);
err_msg:
sem_exit_ns(ns);
err_sem:
kfree(ns);
err_mem:
return ERR_PTR(err);
}
struct ipc_namespace *copy_ipcs(unsigned long flags, struct ipc_namespace *ns)
{
struct ipc_namespace *new_ns;
BUG_ON(!ns);
get_ipc_ns(ns);
if (!(flags & CLONE_NEWIPC))
return ns;
new_ns = clone_ipc_ns(ns);
put_ipc_ns(ns);
return new_ns;
}
void free_ipc_ns(struct kref *kref)
{
struct ipc_namespace *ns;
ns = container_of(kref, struct ipc_namespace, kref);
sem_exit_ns(ns);
msg_exit_ns(ns);
shm_exit_ns(ns);
kfree(ns);
}

View file

@ -82,6 +82,7 @@
#include <linux/seq_file.h>
#include <linux/rwsem.h>
#include <linux/nsproxy.h>
#include <linux/ipc_namespace.h>
#include <asm/uaccess.h>
#include "util.h"
@ -128,6 +129,7 @@ static void __sem_init_ns(struct ipc_namespace *ns, struct ipc_ids *ids)
ipc_init_ids(ids);
}
#ifdef CONFIG_IPC_NS
int sem_init_ns(struct ipc_namespace *ns)
{
struct ipc_ids *ids;
@ -165,6 +167,7 @@ void sem_exit_ns(struct ipc_namespace *ns)
kfree(ns->ids[IPC_SEM_IDS]);
ns->ids[IPC_SEM_IDS] = NULL;
}
#endif
void __init sem_init (void)
{

View file

@ -38,6 +38,7 @@
#include <linux/rwsem.h>
#include <linux/nsproxy.h>
#include <linux/mount.h>
#include <linux/ipc_namespace.h>
#include <asm/uaccess.h>
@ -96,6 +97,7 @@ static void do_shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *shp)
shm_destroy(ns, shp);
}
#ifdef CONFIG_IPC_NS
int shm_init_ns(struct ipc_namespace *ns)
{
struct ipc_ids *ids;
@ -133,6 +135,7 @@ void shm_exit_ns(struct ipc_namespace *ns)
kfree(ns->ids[IPC_SHM_IDS]);
ns->ids[IPC_SHM_IDS] = NULL;
}
#endif
void __init shm_init (void)
{

View file

@ -33,6 +33,7 @@
#include <linux/audit.h>
#include <linux/nsproxy.h>
#include <linux/rwsem.h>
#include <linux/ipc_namespace.h>
#include <asm/unistd.h>
@ -51,66 +52,6 @@ struct ipc_namespace init_ipc_ns = {
},
};
static struct ipc_namespace *clone_ipc_ns(struct ipc_namespace *old_ns)
{
int err;
struct ipc_namespace *ns;
err = -ENOMEM;
ns = kmalloc(sizeof(struct ipc_namespace), GFP_KERNEL);
if (ns == NULL)
goto err_mem;
err = sem_init_ns(ns);
if (err)
goto err_sem;
err = msg_init_ns(ns);
if (err)
goto err_msg;
err = shm_init_ns(ns);
if (err)
goto err_shm;
kref_init(&ns->kref);
return ns;
err_shm:
msg_exit_ns(ns);
err_msg:
sem_exit_ns(ns);
err_sem:
kfree(ns);
err_mem:
return ERR_PTR(err);
}
struct ipc_namespace *copy_ipcs(unsigned long flags, struct ipc_namespace *ns)
{
struct ipc_namespace *new_ns;
BUG_ON(!ns);
get_ipc_ns(ns);
if (!(flags & CLONE_NEWIPC))
return ns;
new_ns = clone_ipc_ns(ns);
put_ipc_ns(ns);
return new_ns;
}
void free_ipc_ns(struct kref *kref)
{
struct ipc_namespace *ns;
ns = container_of(kref, struct ipc_namespace, kref);
sem_exit_ns(ns);
msg_exit_ns(ns);
shm_exit_ns(ns);
kfree(ns);
}
/**
* ipc_init - initialise IPC subsystem
*

View file

@ -20,6 +20,8 @@ void sem_init (void);
void msg_init (void);
void shm_init (void);
struct ipc_namespace;
int sem_init_ns(struct ipc_namespace *ns);
int msg_init_ns(struct ipc_namespace *ns);
int shm_init_ns(struct ipc_namespace *ns);

View file

@ -21,6 +21,7 @@
#include <linux/utsname.h>
#include <linux/pid_namespace.h>
#include <net/net_namespace.h>
#include <linux/ipc_namespace.h>
static struct kmem_cache *nsproxy_cachep;