forked from luck/tmp_suning_uos_patched
b6b337ad1c
Introduce the registration of a callback routine that recomputes msg_ctlmni upon memory add / remove. A single notifier block is registered in the hotplug memory chain for all the ipc namespaces. Since the ipc namespaces are not linked together, they have their own notification chain: one notifier_block is defined per ipc namespace. Each time an ipc namespace is created (removed) it registers (unregisters) its notifier block in (from) the ipcns chain. The callback routine registered in the memory chain invokes the ipcns notifier chain with the IPCNS_LOWMEM event. Each callback routine registered in the ipcns namespace, in turn, recomputes msgmni for the owning namespace. Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Mingming Cao <cmm@us.ibm.com> Cc: Pierre Peiffer <pierre.peiffer@bull.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
122 lines
2.4 KiB
C
122 lines
2.4 KiB
C
#ifndef __IPC_NAMESPACE_H__
|
|
#define __IPC_NAMESPACE_H__
|
|
|
|
#include <linux/err.h>
|
|
#include <linux/idr.h>
|
|
#include <linux/rwsem.h>
|
|
#ifdef CONFIG_MEMORY_HOTPLUG
|
|
#include <linux/notifier.h>
|
|
#endif /* CONFIG_MEMORY_HOTPLUG */
|
|
|
|
/*
|
|
* ipc namespace events
|
|
*/
|
|
#define IPCNS_MEMCHANGED 0x00000001 /* Notify lowmem size changed */
|
|
|
|
#define IPCNS_CALLBACK_PRI 0
|
|
|
|
|
|
struct ipc_ids {
|
|
int in_use;
|
|
unsigned short seq;
|
|
unsigned short seq_max;
|
|
struct rw_semaphore rw_mutex;
|
|
struct idr ipcs_idr;
|
|
};
|
|
|
|
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;
|
|
|
|
#ifdef CONFIG_MEMORY_HOTPLUG
|
|
struct notifier_block ipcns_nb;
|
|
#endif
|
|
};
|
|
|
|
extern struct ipc_namespace init_ipc_ns;
|
|
extern atomic_t nr_ipc_ns;
|
|
|
|
#ifdef CONFIG_SYSVIPC
|
|
#define INIT_IPC_NS(ns) .ns = &init_ipc_ns,
|
|
|
|
#ifdef CONFIG_MEMORY_HOTPLUG
|
|
|
|
extern int register_ipcns_notifier(struct ipc_namespace *);
|
|
extern int unregister_ipcns_notifier(struct ipc_namespace *);
|
|
extern int ipcns_notify(unsigned long);
|
|
|
|
#else /* CONFIG_MEMORY_HOTPLUG */
|
|
|
|
static inline int register_ipcns_notifier(struct ipc_namespace *ipcns)
|
|
{
|
|
return 0;
|
|
}
|
|
static inline int unregister_ipcns_notifier(struct ipc_namespace *ipcns)
|
|
{
|
|
return 0;
|
|
}
|
|
static inline int ipcns_notify(unsigned long ev)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
#endif /* CONFIG_MEMORY_HOTPLUG */
|
|
|
|
#else /* CONFIG_SYSVIPC */
|
|
#define INIT_IPC_NS(ns)
|
|
#endif /* CONFIG_SYSVIPC */
|
|
|
|
#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);
|
|
extern void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids,
|
|
void (*free)(struct ipc_namespace *,
|
|
struct kern_ipc_perm *));
|
|
|
|
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
|