IPC: consolidate sem_exit_ns(), msg_exit_ns() and shm_exit_ns()

sem_exit_ns(), msg_exit_ns() and shm_exit_ns() are all called when an
ipc_namespace is released to free all ipcs of each type.  But in fact, they
do the same thing: they loop around all ipcs to free them individually by
calling a specific routine.

This patch proposes to consolidate this by introducing a common function,
free_ipcs(), that do the job.  The specific routine to call on each
individual ipcs is passed as parameter.  For this, these ipc-specific
'free' routines are reworked to take a generic 'struct ipc_perm' as
parameter.

Signed-off-by: Pierre Peiffer <pierre.peiffer@bull.net>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Pierre Peiffer 2008-02-08 04:18:57 -08:00 committed by Linus Torvalds
parent ed2ddbf88c
commit 01b8b07a5d
5 changed files with 50 additions and 67 deletions

View file

@ -44,6 +44,9 @@ extern struct ipc_namespace init_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)
{

View file

@ -72,7 +72,7 @@ struct msg_sender {
#define msg_unlock(msq) ipc_unlock(&(msq)->q_perm)
#define msg_buildid(id, seq) ipc_buildid(id, seq)
static void freeque(struct ipc_namespace *, struct msg_queue *);
static void freeque(struct ipc_namespace *, struct kern_ipc_perm *);
static int newque(struct ipc_namespace *, struct ipc_params *);
#ifdef CONFIG_PROC_FS
static int sysvipc_msg_proc_show(struct seq_file *s, void *it);
@ -91,26 +91,7 @@ void msg_init_ns(struct ipc_namespace *ns)
#ifdef CONFIG_IPC_NS
void msg_exit_ns(struct ipc_namespace *ns)
{
struct msg_queue *msq;
struct kern_ipc_perm *perm;
int next_id;
int total, in_use;
down_write(&msg_ids(ns).rw_mutex);
in_use = msg_ids(ns).in_use;
for (total = 0, next_id = 0; total < in_use; next_id++) {
perm = idr_find(&msg_ids(ns).ipcs_idr, next_id);
if (perm == NULL)
continue;
ipc_lock_by_ptr(perm);
msq = container_of(perm, struct msg_queue, q_perm);
freeque(ns, msq);
total++;
}
up_write(&msg_ids(ns).rw_mutex);
free_ipcs(ns, &msg_ids(ns), freeque);
}
#endif
@ -274,9 +255,10 @@ static void expunge_all(struct msg_queue *msq, int res)
* msg_ids.rw_mutex (writer) and the spinlock for this message queue are held
* before freeque() is called. msg_ids.rw_mutex remains locked on exit.
*/
static void freeque(struct ipc_namespace *ns, struct msg_queue *msq)
static void freeque(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
{
struct list_head *tmp;
struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm);
expunge_all(msq, -EIDRM);
ss_wakeup(&msq->q_senders, 1);
@ -582,7 +564,7 @@ asmlinkage long sys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf)
break;
}
case IPC_RMID:
freeque(ns, msq);
freeque(ns, &msq->q_perm);
break;
}
err = 0;

View file

@ -44,6 +44,36 @@ struct ipc_namespace *copy_ipcs(unsigned long flags, struct ipc_namespace *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;

View file

@ -94,7 +94,7 @@
#define sem_buildid(id, seq) ipc_buildid(id, seq)
static int newary(struct ipc_namespace *, struct ipc_params *);
static void freeary(struct ipc_namespace *, struct sem_array *);
static void freeary(struct ipc_namespace *, struct kern_ipc_perm *);
#ifdef CONFIG_PROC_FS
static int sysvipc_sem_proc_show(struct seq_file *s, void *it);
#endif
@ -129,25 +129,7 @@ void sem_init_ns(struct ipc_namespace *ns)
#ifdef CONFIG_IPC_NS
void sem_exit_ns(struct ipc_namespace *ns)
{
struct sem_array *sma;
struct kern_ipc_perm *perm;
int next_id;
int total, in_use;
down_write(&sem_ids(ns).rw_mutex);
in_use = sem_ids(ns).in_use;
for (total = 0, next_id = 0; total < in_use; next_id++) {
perm = idr_find(&sem_ids(ns).ipcs_idr, next_id);
if (perm == NULL)
continue;
ipc_lock_by_ptr(perm);
sma = container_of(perm, struct sem_array, sem_perm);
freeary(ns, sma);
total++;
}
up_write(&sem_ids(ns).rw_mutex);
free_ipcs(ns, &sem_ids(ns), freeary);
}
#endif
@ -542,10 +524,11 @@ static int count_semzcnt (struct sem_array * sma, ushort semnum)
* as a writer and the spinlock for this semaphore set hold. sem_ids.rw_mutex
* remains locked on exit.
*/
static void freeary(struct ipc_namespace *ns, struct sem_array *sma)
static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
{
struct sem_undo *un;
struct sem_queue *q;
struct sem_array *sma = container_of(ipcp, struct sem_array, sem_perm);
/* Invalidate the existing undo structures for this semaphore set.
* (They will be freed without any further action in exit_sem()
@ -926,7 +909,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, int semnum,
switch(cmd){
case IPC_RMID:
freeary(ns, sma);
freeary(ns, ipcp);
err = 0;
break;
case IPC_SET:

View file

@ -83,8 +83,11 @@ void shm_init_ns(struct ipc_namespace *ns)
* Called with shm_ids.rw_mutex (writer) and the shp structure locked.
* Only shm_ids.rw_mutex remains locked on exit.
*/
static void do_shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *shp)
static void do_shm_rmid(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
{
struct shmid_kernel *shp;
shp = container_of(ipcp, struct shmid_kernel, shm_perm);
if (shp->shm_nattch){
shp->shm_perm.mode |= SHM_DEST;
/* Do not find it any more */
@ -97,25 +100,7 @@ static void do_shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *shp)
#ifdef CONFIG_IPC_NS
void shm_exit_ns(struct ipc_namespace *ns)
{
struct shmid_kernel *shp;
struct kern_ipc_perm *perm;
int next_id;
int total, in_use;
down_write(&shm_ids(ns).rw_mutex);
in_use = shm_ids(ns).in_use;
for (total = 0, next_id = 0; total < in_use; next_id++) {
perm = idr_find(&shm_ids(ns).ipcs_idr, next_id);
if (perm == NULL)
continue;
ipc_lock_by_ptr(perm);
shp = container_of(perm, struct shmid_kernel, shm_perm);
do_shm_rmid(ns, shp);
total++;
}
up_write(&shm_ids(ns).rw_mutex);
free_ipcs(ns, &shm_ids(ns), do_shm_rmid);
}
#endif
@ -832,7 +817,7 @@ asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds __user *buf)
if (err)
goto out_unlock_up;
do_shm_rmid(ns, shp);
do_shm_rmid(ns, &shp->shm_perm);
up_write(&shm_ids(ns).rw_mutex);
goto out;
}