Пример #1
0
void
ipc_mqueue_move(
	ipc_mqueue_t		dest,
	ipc_mqueue_t		source,
	const ipc_port_t	port)
{
	ipc_kmsg_queue_t oldq, newq;
	ipc_thread_queue_t blockedq;
	ipc_kmsg_t kmsg, next;
	ipc_thread_t th;

	oldq = &source->imq_messages;
	newq = &dest->imq_messages;
	blockedq = &dest->imq_threads;

	for (kmsg = ipc_kmsg_queue_first(oldq);
	     kmsg != IKM_NULL; kmsg = next) {
		next = ipc_kmsg_queue_next(oldq, kmsg);

		/* only move messages sent to port */

		if (kmsg->ikm_header.msgh_remote_port != (mach_port_t) port)
			continue;

		ipc_kmsg_rmqueue(oldq, kmsg);

		/* before adding kmsg to newq, check for a blocked receiver */

		while ((th = ipc_thread_dequeue(blockedq)) != ITH_NULL) {
			assert(ipc_kmsg_queue_empty(newq));

			thread_go(th);

			/* check if the receiver can handle the message */

			if (kmsg->ikm_header.msgh_size <= th->ith_msize) {
				th->ith_state = MACH_MSG_SUCCESS;
				th->ith_kmsg = kmsg;
				th->ith_seqno = port->ip_seqno++;

				goto next_kmsg;
			}

			th->ith_state = MACH_RCV_TOO_LARGE;
			th->ith_msize = kmsg->ikm_header.msgh_size;
		}

		/* didn't find a receiver to handle the message */

		ipc_kmsg_enqueue(newq, kmsg);
	    next_kmsg:;
	}
}
Пример #2
0
void
ipc_mqueue_move(
	ipc_mqueue_t	dest,
	ipc_mqueue_t	source,
	ipc_port_t	port)
{
	ipc_kmsg_queue_t oldq, newq;
	ipc_thread_queue_t blockedq;
	ipc_kmsg_t kmsg, next;
	ipc_thread_t th;

	oldq = &source->imq_messages;
	newq = &dest->imq_messages;
	blockedq = &dest->imq_threads;

	for (kmsg = ipc_kmsg_queue_first(oldq); kmsg != IKM_NULL; kmsg = next) {
		next = ipc_kmsg_queue_next(oldq, kmsg);

		/* only move messages sent to port */

		if (kmsg->ikm_header.msgh_remote_port != (mach_port_t) port)
			continue;

		ipc_kmsg_rmqueue(oldq, kmsg);

		/* before adding kmsg to newq, check for a blocked receiver */

		if ((th = ipc_thread_dequeue(blockedq)) != ITH_NULL) {
			assert(ipc_kmsg_queue_empty(newq));

			/*
			 * Got a receiver.  Hand the receiver the message
			 * and process the next one.
			 */
			th->ith_state = MACH_MSG_SUCCESS;
			th->ith_kmsg = kmsg;
			th->ith_seqno = port->ip_seqno++;
			thread_go(th);
		} else {
			/* didn't find a receiver; enqueue the message */
			ipc_kmsg_enqueue(newq, kmsg);
		}
	}
}
Пример #3
0
/*  flipc_port_destroy() is called to convert a flipc port back to a
 *  local-only ipc port (i.e., the port has no remaining off-node rights).
 *  This will dispose of any undelivered flipc messages, generating NAKs if
 *  needed.  <lport> must be locked on entry and is not unlocked on return.
 */
static void
flipc_port_destroy(ipc_port_t lport)
{
    /* Ensure parameter is valid, and linked to an fport with a valid name */
    assert(IP_VALID(lport));
    ipc_mqueue_t port_mq = &lport->ip_messages;
    flipc_port_t fport = port_mq->data.port.fport;
    assert(FPORT_VALID(fport));
    assert(MNL_NAME_VALID(fport->obj.name));

    /* Dispose of any undelivered messages */
    int m = port_mq->data.port.msgcount;
    if (m > 0) {
        ipc_kmsg_t kmsg;
#ifdef DEBUG
        printf("flipc: destroying %p with %d undelivered msgs\n", lport, m);
#endif

        /* Logic was lifted from ipc_mqueue_select_on_thread() */
        while (m--) {
            kmsg = ipc_kmsg_queue_first(&port_mq->imq_messages);
            assert(kmsg != IKM_NULL);
            ipc_kmsg_rmqueue(&port_mq->imq_messages, kmsg);
            if (fport->state == FPORT_STATE_PRINCIPAL)
                flipc_msg_ack(kmsg->ikm_node, port_mq, FALSE);
            ipc_mqueue_release_msgcount(port_mq, NULL);
            port_mq->imq_seqno++;
        }
    }

    /* Remove from name hash table, unlink co-structures, and free fport */
    mnl_obj_remove(fport->obj.name);
    lport->ip_messages.data.port.fport = FPORT_NULL;
    fport->lport = IP_NULL;
    zfree(flipc_port_zone, fport);
}
Пример #4
0
/*
 *	Routine:	ipc_mqueue_add
 *	Purpose:
 *		Associate the portset's mqueue with the port's mqueue.
 *		This has to be done so that posting the port will wakeup
 *		a portset waiter.  If there are waiters on the portset
 *		mqueue and messages on the port mqueue, try to match them
 *		up now.
 *	Conditions:
 *		May block.
 */
kern_return_t
ipc_mqueue_add(
	ipc_mqueue_t	 port_mqueue,
	ipc_mqueue_t	 set_mqueue,
	wait_queue_link_t wql)
{
	wait_queue_t	 port_waitq = &port_mqueue->imq_wait_queue;
	wait_queue_set_t set_waitq = &set_mqueue->imq_set_queue;
	ipc_kmsg_queue_t kmsgq;
	ipc_kmsg_t       kmsg, next;
	kern_return_t	 kr;
	spl_t		 s;

	kr = wait_queue_link_noalloc(port_waitq, set_waitq, wql);
	if (kr != KERN_SUCCESS)
		return kr;

	/*
	 * Now that the set has been added to the port, there may be
	 * messages queued on the port and threads waiting on the set
	 * waitq.  Lets get them together.
	 */
	s = splsched();
	imq_lock(port_mqueue);
	kmsgq = &port_mqueue->imq_messages;
	for (kmsg = ipc_kmsg_queue_first(kmsgq);
	     kmsg != IKM_NULL;
	     kmsg = next) {
		next = ipc_kmsg_queue_next(kmsgq, kmsg);

		for (;;) {
			thread_t th;
			mach_msg_size_t msize;

			th = wait_queue_wakeup64_identity_locked(
						port_waitq,
						IPC_MQUEUE_RECEIVE,
						THREAD_AWAKENED,
						FALSE);
			/* waitq/mqueue still locked, thread locked */

			if (th == THREAD_NULL)
				goto leave;

			/*
			 * If the receiver waited with a facility not directly
			 * related to Mach messaging, then it isn't prepared to get
			 * handed the message directly.  Just set it running, and
			 * go look for another thread that can.
			 */
			if (th->ith_state != MACH_RCV_IN_PROGRESS) {
				  thread_unlock(th);
				  continue;
			}

			/*
			 * Found a receiver. see if they can handle the message
			 * correctly (the message is not too large for them, or
			 * they didn't care to be informed that the message was
			 * too large).  If they can't handle it, take them off
			 * the list and let them go back and figure it out and
			 * just move onto the next.
			 */
			msize = ipc_kmsg_copyout_size(kmsg, th->map);
			if (th->ith_msize <
					(msize + REQUESTED_TRAILER_SIZE(thread_is_64bit(th), th->ith_option))) {
				th->ith_state = MACH_RCV_TOO_LARGE;
				th->ith_msize = msize;
				if (th->ith_option & MACH_RCV_LARGE) {
					/*
					 * let him go without message
					 */
					th->ith_receiver_name = port_mqueue->imq_receiver_name;
					th->ith_kmsg = IKM_NULL;
					th->ith_seqno = 0;
					thread_unlock(th);
					continue; /* find another thread */
				}
			} else {
				th->ith_state = MACH_MSG_SUCCESS;
			}

			/*
			 * This thread is going to take this message,
			 * so give it to him.
			 */
			ipc_kmsg_rmqueue(kmsgq, kmsg);
			ipc_mqueue_release_msgcount(port_mqueue);

			th->ith_kmsg = kmsg;
			th->ith_seqno = port_mqueue->imq_seqno++;
			thread_unlock(th);
			break;  /* go to next message */
		}
			
	}
 leave:
	imq_unlock(port_mqueue);
	splx(s);
	return KERN_SUCCESS;
}