/**
* newque - Create a new msg queue
* @ns: namespace
* @params: ptr to the structure that contains the key and msgflg
*
* Called with msg_ids.rw_mutex held (writer)
*/
static int newque(struct ipc_namespace *ns, struct ipc_params *params)
{
struct msg_queue *msq;
int id, retval;
key_t key = params->key;
int msgflg = params->flg;
msq = ipc_rcu_alloc(sizeof(*msq));
if (!msq)
return -ENOMEM;
msq->q_perm.mode = msgflg & S_IRWXUGO;
msq->q_perm.key = key;
msq->q_perm.security = NULL;
retval = security_msg_queue_alloc(msq);
if (retval) {
ipc_rcu_putref(msq);
return retval;
}
/*
* ipc_addid() locks msq
*/
id = ipc_addid(&msg_ids(ns), &msq->q_perm, ns->msg_ctlmni);
if (id < 0) {
security_msg_queue_free(msq);
ipc_rcu_putref(msq);
return id;
}
msq->q_stime = msq->q_rtime = 0;
msq->q_ctime = get_seconds();
msq->q_cbytes = msq->q_qnum = 0;
msq->q_qbytes = ns->msg_ctlmnb;
msq->q_lspid = msq->q_lrpid = 0;
INIT_LIST_HEAD(&msq->q_messages);
INIT_LIST_HEAD(&msq->q_receivers);
INIT_LIST_HEAD(&msq->q_senders);
msg_unlock(msq);
return msq->q_perm.id;
}
/*
* freeque() wakes up waiters on the sender and receiver waiting queue,
* removes the message queue from message queue ID
* array, and cleans up all the messages associated with this queue.
*
* msg_ids.sem and the spinlock for this message queue is hold
* before freeque() is called. msg_ids.sem remains locked on exit.
*/
static void freeque (struct msg_queue *msq, int id)
{
struct list_head *tmp;
expunge_all(msq,-EIDRM);
ss_wakeup(&msq->q_senders,1);
msq = msg_rmid(id);
msg_unlock(msq);
tmp = msq->q_messages.next;
while(tmp != &msq->q_messages) {
struct msg_msg* msg = list_entry(tmp,struct msg_msg,m_list);
tmp = tmp->next;
atomic_dec(&msg_hdrs);
free_msg(msg);
}
atomic_sub(msq->q_cbytes, &msg_bytes);
security_msg_queue_free(msq);
ipc_rcu_free(msq, sizeof(struct msg_queue));
}
/*
* freeque() wakes up waiters on the sender and receiver waiting queue,
* removes the message queue from message queue ID IDR, and cleans up all the
* messages associated with this queue.
*
* 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 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);
msg_rmid(ns, msq);
msg_unlock(msq);
tmp = msq->q_messages.next;
while (tmp != &msq->q_messages) {
struct msg_msg *msg = list_entry(tmp, struct msg_msg, m_list);
tmp = tmp->next;
atomic_dec(&ns->msg_hdrs);
free_msg(msg);
}
atomic_sub(msq->q_cbytes, &ns->msg_bytes);
security_msg_queue_free(msq);
ipc_rcu_putref(msq);
}
static int newque (key_t key, int msgflg)
{
int id;
int retval;
struct msg_queue *msq;
msq = ipc_rcu_alloc(sizeof(*msq));
if (!msq)
return -ENOMEM;
msq->q_perm.mode = (msgflg & S_IRWXUGO);
msq->q_perm.key = key;
msq->q_perm.security = NULL;
retval = security_msg_queue_alloc(msq);
if (retval) {
ipc_rcu_free(msq, sizeof(*msq));
return retval;
}
id = ipc_addid(&msg_ids, &msq->q_perm, msg_ctlmni);
if(id == -1) {
security_msg_queue_free(msq);
ipc_rcu_free(msq, sizeof(*msq));
return -ENOSPC;
}
msq->q_stime = msq->q_rtime = 0;
msq->q_ctime = get_seconds();
msq->q_cbytes = msq->q_qnum = 0;
msq->q_qbytes = msg_ctlmnb;
msq->q_lspid = msq->q_lrpid = 0;
INIT_LIST_HEAD(&msq->q_messages);
INIT_LIST_HEAD(&msq->q_receivers);
INIT_LIST_HEAD(&msq->q_senders);
msg_unlock(msq);
return msg_buildid(id,msq->q_perm.seq);
}
