linux-stable-rt/ipc/namespace.c

87 lines
1.7 KiB
C

/*
* 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)
{
struct ipc_namespace *ns;
ns = kmalloc(sizeof(struct ipc_namespace), GFP_KERNEL);
if (ns == NULL)
return ERR_PTR(-ENOMEM);
sem_init_ns(ns);
msg_init_ns(ns);
shm_init_ns(ns);
kref_init(&ns->kref);
return ns;
}
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;
}
/*
* free_ipcs - free all ipcs of one type
* @ns: the namespace to remove the ipcs from
* @ids: the table of ipcs to free
* @free: the function called to free each individual ipc
*
* Called for each kind of ipc when an ipc_namespace exits.
*/
void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids,
void (*free)(struct ipc_namespace *, struct kern_ipc_perm *))
{
struct kern_ipc_perm *perm;
int next_id;
int total, in_use;
down_write(&ids->rw_mutex);
in_use = ids->in_use;
for (total = 0, next_id = 0; total < in_use; next_id++) {
perm = idr_find(&ids->ipcs_idr, next_id);
if (perm == NULL)
continue;
ipc_lock_by_ptr(perm);
free(ns, perm);
total++;
}
up_write(&ids->rw_mutex);
}
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);
}