ctcmain.c

内核linux2.4.20,可跟rtlinux3.2打补丁 组成实时linux系统,编译内核

		ch->ccw[1].count = 0;
		ch->trans_skb_data = ch->trans_skb->data;
		ch->flags &= ~CHANNEL_FLAGS_BUFSIZE_CHANGED;
	}
	return 0;
}

/**
 * Dummy NOP action for statemachines
 */
static void fsm_action_nop(fsm_instance *fi, int event, void *arg)
{
}

/**
 * Actions for channel - statemachines.
 *****************************************************************************/

/**
 * Normal data has been send. Free the corresponding
 * skb (it's in io_queue), reset dev->tbusy and
 * revert to idle state.
 *
 * @param fi    An instance of a channel statemachine.
 * @param event The event, just happened.
 * @param arg   Generic pointer, casted from channel * upon call.
 */
static void ch_action_txdone(fsm_instance *fi, int event, void *arg)
{
	channel        *ch = (channel *)arg;
	net_device     *dev = ch->netdev;
	ctc_priv       *privptr = dev->priv;
	struct sk_buff *skb;
	int            first = 1;
	int            i;

	struct timeval done_stamp = xtime;
	unsigned long duration = 
		(done_stamp.tv_sec - ch->prof.send_stamp.tv_sec) * 1000000 +
		done_stamp.tv_usec - ch->prof.send_stamp.tv_usec;
	if (duration > ch->prof.tx_time)
		ch->prof.tx_time = duration;

	if (ch->devstat->rescnt != 0)
		printk(KERN_DEBUG "%s: TX not complete, remaining %d bytes\n",
		       dev->name, ch->devstat->rescnt);
	
	fsm_deltimer(&ch->timer);
	while ((skb = skb_dequeue(&ch->io_queue))) {
		privptr->stats.tx_packets++;
		privptr->stats.tx_bytes += skb->len - LL_HEADER_LENGTH;
		if (first) {
			privptr->stats.tx_bytes += 2;
			first = 0;
		}
		atomic_dec(&skb->users);
		dev_kfree_skb_irq(skb);
	}
	spin_lock(&ch->collect_lock);
	clear_normalized_cda(&ch->ccw[4]);
	if (ch->collect_len > 0) {
		int rc;

		if (ctc_checkalloc_buffer(ch, 1)) {
			spin_unlock(&ch->collect_lock);
			return;
		}
		ch->trans_skb->tail = ch->trans_skb->data = ch->trans_skb_data;
		ch->trans_skb->len = 0;
		if (ch->prof.maxmulti < (ch->collect_len + 2))
			ch->prof.maxmulti = ch->collect_len + 2;
		if (ch->prof.maxcqueue < skb_queue_len(&ch->collect_queue))
			ch->prof.maxcqueue = skb_queue_len(&ch->collect_queue);
		*((__u16 *)skb_put(ch->trans_skb, 2)) = ch->collect_len + 2;
		i = 0;
		while ((skb = skb_dequeue(&ch->collect_queue))) {
			memcpy(skb_put(ch->trans_skb, skb->len), skb->data,
			       skb->len);
			privptr->stats.tx_packets++;
			privptr->stats.tx_bytes += skb->len - LL_HEADER_LENGTH;
			atomic_dec(&skb->users);
			dev_kfree_skb_irq(skb);
			i++;
		}
		ch->collect_len = 0;
		spin_unlock(&ch->collect_lock);
		ch->ccw[1].count = ch->trans_skb->len;
		fsm_addtimer(&ch->timer, CTC_TIMEOUT_5SEC, CH_EVENT_TIMER, ch);
		ch->prof.send_stamp = xtime;
		rc = do_IO(ch->irq, &ch->ccw[0], (intparm_t)ch, 0xff, 0);
		ch->prof.doios_multi++;
		if (rc != 0) {
			privptr->stats.tx_dropped += i;
			privptr->stats.tx_errors += i;
			fsm_deltimer(&ch->timer);
			ccw_check_return_code(ch, rc);
		}
	} else {
		spin_unlock(&ch->collect_lock);
		fsm_newstate(fi, CH_STATE_TXIDLE);
	}
	ctc_clear_busy(dev);
}

/**
 * Initial data is sent.
 * Notify device statemachine that we are up and
 * running.
 *
 * @param fi    An instance of a channel statemachine.
 * @param event The event, just happened.
 * @param arg   Generic pointer, casted from channel * upon call.
 */
static void ch_action_txidle(fsm_instance *fi, int event, void *arg)
{
	channel *ch = (channel *)arg;

	fsm_deltimer(&ch->timer);
	fsm_newstate(fi, CH_STATE_TXIDLE);
	fsm_event(((ctc_priv *)ch->netdev->priv)->fsm, DEV_EVENT_TXUP,
		  ch->netdev);
}

/**
 * Got normal data, check for sanity, queue it up, allocate new buffer
 * trigger bottom half, and initiate next read.
 *
 * @param fi    An instance of a channel statemachine.
 * @param event The event, just happened.
 * @param arg   Generic pointer, casted from channel * upon call.
 */
static void ch_action_rx(fsm_instance *fi, int event, void *arg)
{
	channel        *ch = (channel *)arg;
	net_device     *dev = ch->netdev;
	ctc_priv       *privptr = dev->priv;
	int            len = ch->max_bufsize - ch->devstat->rescnt;
	struct sk_buff *skb = ch->trans_skb;
	__u16          block_len = *((__u16*)skb->data);
	int            check_len;
	int            rc;

	fsm_deltimer(&ch->timer);
	if (len < 8) {
		printk(KERN_WARNING "%s: got packet with length %d < 8\n",
		       dev->name, len);
		privptr->stats.rx_dropped++;
		privptr->stats.rx_length_errors++;
		goto again;
	}
	if (len > ch->max_bufsize) {
		printk(KERN_WARNING "%s: got packet with length %d > %d\n",
		       dev->name, len, ch->max_bufsize);
		privptr->stats.rx_dropped++;
		privptr->stats.rx_length_errors++;
		goto again;
	}

	/**
	 * VM TCP seems to have a bug sending 2 trailing bytes of garbage.
	 */
	switch (ch->protocol) {
		case CTC_PROTO_S390:
		case CTC_PROTO_OS390:
			check_len = block_len + 2;
			break;
		default:
			check_len = block_len;
			break;
	}
	if ((len < block_len) || (len > check_len)) {
		printk(KERN_WARNING "%s: got block length %d != rx length %d\n",
		       dev->name, block_len, len);
#ifdef DEBUG
		ctc_dump_skb(skb, 0);
#endif
		*((__u16*)skb->data) = len;
		privptr->stats.rx_dropped++;
		privptr->stats.rx_length_errors++;
		goto again;
	}
	block_len -= 2;
	if (block_len > 0) {
		*((__u16*)skb->data) = block_len;
		ctc_unpack_skb(ch, skb);
	}
 again:
	skb->data = skb->tail = ch->trans_skb_data;
	skb->len = 0;
	if (ctc_checkalloc_buffer(ch, 1))
		return;
	ch->ccw[1].count = ch->max_bufsize;
	rc = do_IO(ch->irq, &ch->ccw[0], (intparm_t)ch, 0xff, 0);
	if (rc != 0)
		ccw_check_return_code(ch, rc);
}

static void ch_action_rxidle(fsm_instance *fi, int event, void *arg);

/**
 * Initialize connection by sending a __u16 of value 0.
 *
 * @param fi    An instance of a channel statemachine.
 * @param event The event, just happened.
 * @param arg   Generic pointer, casted from channel * upon call.
 */
static void ch_action_firstio(fsm_instance *fi, int event, void *arg)
{
	channel *ch = (channel *)arg;
	int     rc;

	if (fsm_getstate(fi) == CH_STATE_TXIDLE)
		printk(KERN_DEBUG "ch-%04x: remote side issued READ?, "
		       "init ...\n", ch->devno);
	fsm_deltimer(&ch->timer);
	if (ctc_checkalloc_buffer(ch, 1))
		return;
	if ((fsm_getstate(fi) == CH_STATE_SETUPWAIT) &&
	    (ch->protocol == CTC_PROTO_OS390)) {
		/* OS/390 resp. z/OS */
		if (CHANNEL_DIRECTION(ch->flags) == READ) {
			*((__u16 *)ch->trans_skb->data) = CTC_INITIAL_BLOCKLEN;
			fsm_addtimer(&ch->timer, CTC_TIMEOUT_5SEC,
				     CH_EVENT_TIMER, ch);
			ch_action_rxidle(fi, event, arg);
		} else {
			net_device *dev = ch->netdev;
			fsm_newstate(fi, CH_STATE_TXIDLE);
			fsm_event(((ctc_priv *)dev->priv)->fsm,
				  DEV_EVENT_TXUP, dev);
		}
		return;
	}

	/**
	 * Don磘 setup a timer for receiving the initial RX frame
	 * if in compatibility mode, since VM TCP delays the initial
	 * frame until it has some data to send.
	 */
	if ((CHANNEL_DIRECTION(ch->flags) == WRITE) ||
	    (ch->protocol != CTC_PROTO_S390))
		fsm_addtimer(&ch->timer, CTC_TIMEOUT_5SEC, CH_EVENT_TIMER, ch);

	*((__u16 *)ch->trans_skb->data) = CTC_INITIAL_BLOCKLEN;
	ch->ccw[1].count = 2; /* Transfer only length */

	fsm_newstate(fi, (CHANNEL_DIRECTION(ch->flags) == READ)
		     ? CH_STATE_RXINIT : CH_STATE_TXINIT);
	rc = do_IO(ch->irq, &ch->ccw[0], (intparm_t)ch, 0xff, 0);
	if (rc != 0) {
		fsm_deltimer(&ch->timer);
		fsm_newstate(fi, CH_STATE_SETUPWAIT);
		ccw_check_return_code(ch, rc);
	}
	/**
	 * If in compatibility mode since we don磘 setup a timer, we
	 * also signal RX channel up immediately. This enables us
	 * to send packets early which in turn usually triggers some
	 * reply from VM TCP which brings up the RX channel to it磗
	 * final state.
	 */
	if ((CHANNEL_DIRECTION(ch->flags) == READ) &&
	    (ch->protocol == CTC_PROTO_S390)) {
		net_device *dev = ch->netdev;
		fsm_event(((ctc_priv *)dev->priv)->fsm, DEV_EVENT_RXUP, dev);
	}
}

/**
 * Got initial data, check it. If OK,
 * notify device statemachine that we are up and
 * running.
 *
 * @param fi    An instance of a channel statemachine.
 * @param event The event, just happened.
 * @param arg   Generic pointer, casted from channel * upon call.
 */
static void ch_action_rxidle(fsm_instance *fi, int event, void *arg)
{
	channel    *ch = (channel *)arg;
	net_device *dev = ch->netdev;
	__u16      buflen;
	int        rc;

	fsm_deltimer(&ch->timer);
	buflen = *((__u16 *)ch->trans_skb->data);
#ifdef DEBUG
	printk(KERN_DEBUG "%s: Initial RX count %d\n", dev->name, buflen);
#endif
	if (buflen >= CTC_INITIAL_BLOCKLEN) {
		if (ctc_checkalloc_buffer(ch, 1))
			return;
		ch->ccw[1].count = ch->max_bufsize;
		fsm_newstate(fi, CH_STATE_RXIDLE);
		rc = do_IO(ch->irq, &ch->ccw[0], (intparm_t)ch, 0xff, 0);
		if (rc != 0) {
			fsm_newstate(fi, CH_STATE_RXINIT);
			ccw_check_return_code(ch, rc);
		} else
			fsm_event(((ctc_priv *)dev->priv)->fsm,
				  DEV_EVENT_RXUP, dev);
	} else {
		printk(KERN_DEBUG "%s: Initial RX count %d not %d\n",
		       dev->name, buflen, CTC_INITIAL_BLOCKLEN);
		ch_action_firstio(fi, event, arg);
	}
}

/**
 * Set channel into extended mode.
 *
 * @param fi    An instance of a channel statemachine.
 * @param event The event, just happened.
 * @param arg   Generic pointer, casted from channel * upon call.
 */
static void ch_action_setmode(fsm_instance *fi, int event, void *arg)
{
	channel *ch = (channel *)arg;
	int     rc;
	unsigned long saveflags;

	fsm_deltimer(&ch->timer);
	fsm_addtimer(&ch->timer, CTC_TIMEOUT_5SEC, CH_EVENT_TIMER, ch);
	fsm_newstate(fi, CH_STATE_SETUPWAIT);
	if (event == CH_EVENT_TIMER)
		s390irq_spin_lock_irqsave(ch->irq, saveflags);
	rc = do_IO(ch->irq, &ch->ccw[6], (intparm_t)ch, 0xff, 0);
	if (event == CH_EVENT_TIMER)
		s390irq_spin_unlock_irqrestore(ch->irq, saveflags);
	if (rc != 0) {
		fsm_deltimer(&ch->timer);
		fsm_newstate(fi, CH_STATE_STARTWAIT);
		ccw_check_return_code(ch, rc);
	} else
		ch->retry = 0;
}

/**
 * Setup channel.
 *
 * @param fi    An instance of a channel statemachine.
 * @param event The event, just happened.
 * @param arg   Generic pointer, casted from channel * upon call.
 */
static void ch_action_start(fsm_instance *fi, int event, void *arg)
{
	channel *ch = (channel *)arg;
	unsigned long saveflags;
	int     rc;
	net_device *dev;

	if (ch == NULL) {
		printk(KERN_WARNING "ch_action_start ch=NULL\n");
		return;
	}
	if (ch->netdev == NULL) {
		printk(KERN_WARNING "ch_action_start dev=NULL, irq=%d\n",
		       ch->irq);
		return;
	}
	dev = ch->netdev;

#ifdef DEBUG
	printk(KERN_DEBUG "%s: %s channel start\n", dev->name,
	       (CHANNEL_DIRECTION(ch->flags) == READ) ? "RX" : "TX");
#endif

	if (ch->trans_skb != NULL) {
		clear_normalized_cda(&ch->ccw[1]);
		dev_kfree_skb(ch->trans_skb);
		ch->trans_skb = NULL;
	}
	if (CHANNEL_DIRECTION(ch->flags) == READ) {
		ch->ccw[1].cmd_code = CCW_CMD_READ;
		ch->ccw[1].flags    = CCW_FLAG_SLI;
		ch->ccw[1].count    = 0;
	} else {
		ch->ccw[1].cmd_code = CCW_CMD_WRITE;
		ch->ccw[1].flags    = CCW_FLAG_SLI | CCW_FLAG_CC;
		ch->ccw[1].count    = 0;
	}
	if (ctc_checkalloc_buffer(ch, 0))
		printk(KERN_NOTICE
		       "%s: Could not allocate %s trans_skb, delaying "
		       "allocation until first transfer\n",
		       dev->name, 
		       (CHANNEL_DIRECTION(ch->flags) == READ) ? "RX" : "TX");

#if LINUX_VERSION_CODE >= 0x020400
	INIT_LIST_HEAD(&ch->tq.list);
#else
	ch->tq.next = NULL;
#endif
	ch->tq.sync    = 0;
	ch->tq.routine = (void *)(void *)ctc_bh;
	ch->tq.data    = ch;

	ch->ccw[0].cmd_code = CCW_CMD_PREPARE;
	ch->ccw[0].flags    = CCW_FLAG_SLI | CCW_FLAG_CC;
	ch->ccw[0].count    = 0;
	ch->ccw[0].cda	    = 0;
	ch->ccw[2].cmd_code = CCW_CMD_NOOP;	 /* jointed CE + DE */
	ch->ccw[2].flags    = CCW_FLAG_SLI;
	ch->ccw[2].count    = 0;
	ch->ccw[2].cda	    = 0;
	memcpy(&ch->ccw[3], &ch->ccw[0], sizeof(ccw1_t) * 3);
	ch->ccw[4].cda	    = 0;
	ch->ccw[4].flags    &= ~CCW_FLAG_IDA;

	fsm_newstate(fi, CH_STATE_STARTWAIT);
	fsm_addtimer(&ch->timer, 1000, CH_EVENT_TIMER, ch);
	s390irq_spin_lock_irqsave(ch->irq, saveflags);
	rc = halt_IO(ch->irq, (intparm_t)ch, 0);
	s390irq_spin_unlock_irqrestore(ch->irq, saveflags);
	if (rc != 0) {
		fsm_deltimer(&ch->timer);
		ccw_check_return_code(ch, rc);
	}
#ifdef DEBUG
	printk(KERN_DEBUG "ctc: %s(): leaving\n", __FUNCTION__);
#endif
}

/**
 * Shutdown a channel.
 *
 * @param fi    An instance of a channel statemachine.
 * @param event The event, just happened.
 * @param arg   Generic pointer, casted from channel * upon call.
 */
static void ch_action_haltio(fsm_instance *fi, int event, void *arg)
{
	channel *ch = (channel *)arg;
	unsigned long saveflags;
	int     rc;
	int     oldstate;

	fsm_deltimer(&ch->timer);
	fsm_addtimer(&ch->timer, CTC_TIMEOUT_5SEC, CH_EVENT_TIMER, ch);
	if (event == CH_EVENT_STOP)
		s390irq_spin_lock_irqsave(ch->irq, saveflags);
	oldstate = fsm_getstate(fi);
	fsm_newstate(fi, CH_STATE_TERM);
	rc = halt_IO (ch->irq, (intparm_t)ch, 0);
	if (event == CH_EVENT_STOP)
		s390irq_spin_unlock_irqrestore(ch->irq, saveflags);
	if (rc != 0) {
		fsm_deltimer(&ch->timer);
		fsm_newstate(fi, oldstate);
		ccw_check_return_code(ch, rc);
	}
}

/**
 * A channel has successfully been halted.
 * Cleanup it's queue and notify interface statemachine.
 *
 * @param fi    An instance of a channel statemachine.
 * @param event The event, just happened.
 * @param arg   Generic pointer, casted from channel * upon call.
 */
static void ch_action_stopped(fsm_instance *fi, int event, void *arg)
{
	channel *ch = (channel *)arg;
	net_device *dev = ch->netdev;

	fsm_deltimer(&ch->timer);
	fsm_newstate(fi, CH_STATE_STOPPED);
	if (ch->trans_skb != NULL) {
		clear_normalized_cda(&ch->ccw[1]);
		dev_kfree_skb(ch->trans_skb);
		ch->trans_skb = NULL;
	}
	if (CHANNEL_DIRECTION(ch->flags) == READ) {
		skb_queue_purge(&ch->io_queue);
		fsm_event(((ctc_priv *)dev->priv)->fsm, DEV_EVENT_RXDOWN, dev);
	} else {
		ctc_purge_skb_queue(&ch->io_queue);
		spin_lock(&ch->collect_lock);
		ctc_purge_skb_queue(&ch->collect_queue);
		ch->collect_len = 0;
		spin_unlock(&ch->collect_lock);
		fsm_event(((ctc_priv *)dev->priv)->fsm, DEV_EVENT_TXDOWN, dev);
	}