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

}

/**
 * A stop command from device statemachine arrived and we are in
 * not operational mode. Set state to stopped.
 *
 * @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_stop(fsm_instance *fi, int event, void *arg)
{
	fsm_newstate(fi, CH_STATE_STOPPED);
}

/**
 * A machine check for no path, not operational status or gone device has
 * happened.
 * Cleanup 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_fail(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_NOTOP);
	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);
	}
}

/**
 * Handle error during setup of 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_setuperr(fsm_instance *fi, int event, void *arg)
{
	channel *ch = (channel *)arg;
	net_device *dev = ch->netdev;

	/**
	 * Special case: Got UC_RCRESET on setmode.
	 * This means that remote side isn't setup. In this case
	 * simply retry after some 10 secs...
	 */
	if ((fsm_getstate(fi) == CH_STATE_SETUPWAIT) &&
	    ((event == CH_EVENT_UC_RCRESET) ||
	     (event == CH_EVENT_UC_RSRESET)   )         ) {
		fsm_newstate(fi, CH_STATE_STARTRETRY);
		fsm_deltimer(&ch->timer);
		fsm_addtimer(&ch->timer, CTC_TIMEOUT_5SEC, CH_EVENT_TIMER, ch);
		if (CHANNEL_DIRECTION(ch->flags) == READ) {
			int rc = halt_IO (ch->irq, (intparm_t)ch, 0);
			if (rc != 0)
				ccw_check_return_code(ch, rc);
		}
		return;
	}

	printk(KERN_DEBUG "%s: Error %s during %s channel setup state=%s\n",
	       dev->name, ch_event_names[event],
	       (CHANNEL_DIRECTION(ch->flags) == READ) ? "RX" : "TX",
	       fsm_getstate_str(fi));
	if (CHANNEL_DIRECTION(ch->flags) == READ) {
		fsm_newstate(fi, CH_STATE_RXERR);
		fsm_event(((ctc_priv *)dev->priv)->fsm, DEV_EVENT_RXDOWN, dev);
	} else {
		fsm_newstate(fi, CH_STATE_TXERR);
		fsm_event(((ctc_priv *)dev->priv)->fsm, DEV_EVENT_TXDOWN, dev);
	}
}

/**
 * Restart a channel after an error.
 *
 * @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_restart(fsm_instance *fi, int event, void *arg)
{
	unsigned long saveflags;
	int   oldstate;
	int   rc;

	channel *ch = (channel *)arg;
	net_device *dev = ch->netdev;

	fsm_deltimer(&ch->timer);
	printk(KERN_DEBUG "%s: %s channel restart\n", dev->name,
	       (CHANNEL_DIRECTION(ch->flags) == READ) ? "RX" : "TX");
	fsm_addtimer(&ch->timer, CTC_TIMEOUT_5SEC, CH_EVENT_TIMER, ch);
	oldstate = fsm_getstate(fi);
	fsm_newstate(fi, CH_STATE_STARTWAIT);
	if (event == CH_EVENT_TIMER)
		s390irq_spin_lock_irqsave(ch->irq, saveflags);
	rc = halt_IO (ch->irq, (intparm_t)ch, 0);
	if (event == CH_EVENT_TIMER)
		s390irq_spin_unlock_irqrestore(ch->irq, saveflags);
	if (rc != 0) {
		fsm_deltimer(&ch->timer);
		fsm_newstate(fi, oldstate);
		ccw_check_return_code(ch, rc);
	}
}

/**
 * Handle error during RX initial handshake (exchange of
 * 0-length block header)
 *
 * @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_rxiniterr(fsm_instance *fi, int event, void *arg)
{
	channel *ch = (channel *)arg;
	net_device *dev = ch->netdev;

	if (event == CH_EVENT_TIMER) {
		fsm_deltimer(&ch->timer);
		printk(KERN_DEBUG "%s: Timeout during RX init handshake\n",
		       dev->name);
		if (ch->retry++ < 3)
			ch_action_restart(fi, event, arg);
		else {
			fsm_newstate(fi, CH_STATE_RXERR);
			fsm_event(((ctc_priv *)dev->priv)->fsm,
				  DEV_EVENT_RXDOWN, dev);
		}
	} else
		printk(KERN_WARNING "%s: Error during RX init handshake\n",
		       dev->name);
}

/**
 * Notify device statemachine if we gave up initialization
 * of RX 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_rxinitfail(fsm_instance *fi, int event, void *arg)
{
	channel *ch = (channel *)arg;
	net_device *dev = ch->netdev;

	fsm_newstate(fi, CH_STATE_RXERR);
	printk(KERN_WARNING "%s: RX initialization failed\n", dev->name);
	printk(KERN_WARNING "%s: RX <-> RX connection detected\n", dev->name);
	fsm_event(((ctc_priv *)dev->priv)->fsm, DEV_EVENT_RXDOWN, dev);
}

/**
 * Handle RX Unit check remote reset (remote disconnected)
 *
 * @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_rxdisc(fsm_instance *fi, int event, void *arg)
{
	channel    *ch = (channel *)arg;
	channel    *ch2;
	net_device *dev = ch->netdev;

	fsm_deltimer(&ch->timer);
	printk(KERN_DEBUG "%s: Got remote disconnect, re-initializing ...\n",
	       dev->name);

	/**
	 * Notify device statemachine
	 */
	fsm_event(((ctc_priv *)dev->priv)->fsm, DEV_EVENT_RXDOWN, dev);
	fsm_event(((ctc_priv *)dev->priv)->fsm, DEV_EVENT_TXDOWN, dev);

	fsm_newstate(fi, CH_STATE_DTERM);
	ch2 = ((ctc_priv *)dev->priv)->channel[WRITE];
	fsm_newstate(ch2->fsm, CH_STATE_DTERM);

	halt_IO(ch->irq, (intparm_t)ch, 0);
	halt_IO(ch2->irq, (intparm_t)ch2, 0);
}

/**
 * Handle error during TX channel initialization.
 *
 * @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_txiniterr(fsm_instance *fi, int event, void *arg)
{
	channel *ch = (channel *)arg;
	net_device *dev = ch->netdev;

	if (event == CH_EVENT_TIMER) {
		fsm_deltimer(&ch->timer);
		printk(KERN_DEBUG "%s: Timeout during TX init handshake\n",
		       dev->name);
		if (ch->retry++ < 3)
			ch_action_restart(fi, event, arg);
		else {
			fsm_newstate(fi, CH_STATE_TXERR);
			fsm_event(((ctc_priv *)dev->priv)->fsm,
				  DEV_EVENT_TXDOWN, dev);
		}
	} else
		printk(KERN_WARNING "%s: Error during TX init handshake\n",
		       dev->name);
}

/**
 * Handle TX timeout by retrying operation.
 *
 * @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_txretry(fsm_instance *fi, int event, void *arg)
{
	channel    *ch = (channel *)arg;
	net_device *dev = ch->netdev;
	unsigned long saveflags;

	fsm_deltimer(&ch->timer);
	if (ch->retry++ > 3) {
		printk(KERN_DEBUG "%s: TX retry failed, restarting channel\n",
		       dev->name);
		fsm_event(((ctc_priv *)dev->priv)->fsm, DEV_EVENT_TXDOWN, dev);
		ch_action_restart(fi, event, arg);
	} else {
		struct sk_buff *skb;

		printk(KERN_DEBUG "%s: TX retry %d\n", dev->name, ch->retry);
		if ((skb = skb_peek(&ch->io_queue))) {
			int rc = 0;

			clear_normalized_cda(&ch->ccw[4]);
			ch->ccw[4].count = skb->len;
			if (set_normalized_cda(&ch->ccw[4],
					       virt_to_phys(skb->data))) {
				printk(KERN_DEBUG "%s: IDAL alloc failed, "
				       "restarting channel\n", dev->name);
				fsm_event(((ctc_priv *)dev->priv)->fsm,
					  DEV_EVENT_TXDOWN, dev);
				ch_action_restart(fi, event, arg);
				return;
			}
			fsm_addtimer(&ch->timer, 1000, CH_EVENT_TIMER, ch);
			if (event == CH_EVENT_TIMER)
				s390irq_spin_lock_irqsave(ch->irq, saveflags);
			rc = do_IO(ch->irq, &ch->ccw[3], (intparm_t)ch, 0xff, 0);
			if (event == CH_EVENT_TIMER)
				s390irq_spin_unlock_irqrestore(ch->irq,
							       saveflags);
			if (rc != 0) {
				fsm_deltimer(&ch->timer);
				ccw_check_return_code(ch, rc);
				ctc_purge_skb_queue(&ch->io_queue);
			}
		}
	}

}

/**
 * Handle fatal errors during an I/O command.
 *
 * @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_iofatal(fsm_instance *fi, int event, void *arg)
{
	channel *ch = (channel *)arg;
	net_device *dev = ch->netdev;

	fsm_deltimer(&ch->timer);
	if (CHANNEL_DIRECTION(ch->flags) == READ) {
		printk(KERN_DEBUG "%s: RX I/O error\n", dev->name);
		fsm_newstate(fi, CH_STATE_RXERR);
		fsm_event(((ctc_priv *)dev->priv)->fsm, DEV_EVENT_RXDOWN, dev);
	} else {
		printk(KERN_DEBUG "%s: TX I/O error\n", dev->name);
		fsm_newstate(fi, CH_STATE_TXERR);
		fsm_event(((ctc_priv *)dev->priv)->fsm, DEV_EVENT_TXDOWN, dev);
	}
}

/**
 * The statemachine for a channel.
 */
static const fsm_node ch_fsm[] = {
	{ CH_STATE_STOPPED,    CH_EVENT_STOP,       fsm_action_nop       },
	{ CH_STATE_STOPPED,    CH_EVENT_START,      ch_action_start      },
	{ CH_STATE_STOPPED,    CH_EVENT_FINSTAT,    fsm_action_nop       },
	{ CH_STATE_STOPPED,    CH_EVENT_MC_FAIL,    fsm_action_nop       },

	{ CH_STATE_NOTOP,      CH_EVENT_STOP,       ch_action_stop       },
	{ CH_STATE_NOTOP,      CH_EVENT_START,      fsm_action_nop       },
	{ CH_STATE_NOTOP,      CH_EVENT_FINSTAT,    fsm_action_nop       },
	{ CH_STATE_NOTOP,      CH_EVENT_MC_FAIL,    fsm_action_nop       },
	{ CH_STATE_NOTOP,      CH_EVENT_MC_GOOD,    ch_action_start      },

	{ CH_STATE_STARTWAIT,  CH_EVENT_STOP,       ch_action_haltio     },
	{ CH_STATE_STARTWAIT,  CH_EVENT_START,      fsm_action_nop       },
	{ CH_STATE_STARTWAIT,  CH_EVENT_FINSTAT,    ch_action_setmode    },
	{ CH_STATE_STARTWAIT,  CH_EVENT_TIMER,      ch_action_setuperr   },
	{ CH_STATE_STARTWAIT,  CH_EVENT_IO_ENODEV,  ch_action_iofatal    },
	{ CH_STATE_STARTWAIT,  CH_EVENT_IO_EIO,     ch_action_iofatal    },
	{ CH_STATE_STARTWAIT,  CH_EVENT_MC_FAIL,    ch_action_fail       },

	{ CH_STATE_STARTRETRY, CH_EVENT_STOP,       ch_action_haltio     },
	{ CH_STATE_STARTRETRY, CH_EVENT_TIMER,      ch_action_setmode    },
	{ CH_STATE_STARTRETRY, CH_EVENT_FINSTAT,    fsm_action_nop       },
	{ CH_STATE_STARTRETRY, CH_EVENT_MC_FAIL,    ch_action_fail       },

	{ CH_STATE_SETUPWAIT,  CH_EVENT_STOP,       ch_action_haltio     },
	{ CH_STATE_SETUPWAIT,  CH_EVENT_START,      fsm_action_nop       },
	{ CH_STATE_SETUPWAIT,  CH_EVENT_FINSTAT,    ch_action_firstio    },
	{ CH_STATE_SETUPWAIT,  CH_EVENT_UC_RCRESET, ch_action_setuperr   },
	{ CH_STATE_SETUPWAIT,  CH_EVENT_UC_RSRESET, ch_action_setuperr   },
	{ CH_STATE_SETUPWAIT,  CH_EVENT_TIMER,      ch_action_setmode    },
	{ CH_STATE_SETUPWAIT,  CH_EVENT_IO_ENODEV,  ch_action_iofatal    },
	{ CH_STATE_SETUPWAIT,  CH_EVENT_IO_EIO,     ch_action_iofatal    },
	{ CH_STATE_SETUPWAIT,  CH_EVENT_MC_FAIL,    ch_action_fail       },

	{ CH_STATE_RXINIT,     CH_EVENT_STOP,       ch_action_haltio     },
	{ CH_STATE_RXINIT,     CH_EVENT_START,      fsm_action_nop       },
	{ CH_STATE_RXINIT,     CH_EVENT_FINSTAT,    ch_action_rxidle     },
	{ CH_STATE_RXINIT,     CH_EVENT_UC_RCRESET, ch_action_rxiniterr  },
	{ CH_STATE_RXINIT,     CH_EVENT_UC_RSRESET, ch_action_rxiniterr  },
	{ CH_STATE_RXINIT,     CH_EVENT_TIMER,      ch_action_rxiniterr  },
	{ CH_STATE_RXINIT,     CH_EVENT_ATTNBUSY,   ch_action_rxinitfail },
	{ CH_STATE_RXINIT,     CH_EVENT_IO_ENODEV,  ch_action_iofatal    },
	{ CH_STATE_RXINIT,     CH_EVENT_IO_EIO,     ch_action_iofatal    },
	{ CH_STATE_RXINIT,     CH_EVENT_UC_ZERO,    ch_action_firstio    },
	{ CH_STATE_RXINIT,     CH_EVENT_MC_FAIL,    ch_action_fail       },

	{ CH_STATE_RXIDLE,     CH_EVENT_STOP,       ch_action_haltio     },
	{ CH_STATE_RXIDLE,     CH_EVENT_START,      fsm_action_nop       },
	{ CH_STATE_RXIDLE,     CH_EVENT_FINSTAT,    ch_action_rx         },
	{ CH_STATE_RXIDLE,     CH_EVENT_UC_RCRESET, ch_action_rxdisc     },
//	{ CH_STATE_RXIDLE,     CH_EVENT_UC_RSRESET, ch_action_rxretry    },
	{ CH_STATE_RXIDLE,     CH_EVENT_IO_ENODEV,  ch_action_iofatal    },
	{ CH_STATE_RXIDLE,     CH_EVENT_IO_EIO,     ch_action_iofatal    },
	{ CH_STATE_RXIDLE,     CH_EVENT_MC_FAIL,    ch_action_fail       },
	{ CH_STATE_RXIDLE,     CH_EVENT_UC_ZERO,    ch_action_rx         },

	{ CH_STATE_TXINIT,     CH_EVENT_STOP,       ch_action_haltio     },
	{ CH_STATE_TXINIT,     CH_EVENT_START,      fsm_action_nop       },
	{ CH_STATE_TXINIT,     CH_EVENT_FINSTAT,    ch_action_txidle     },
	{ CH_STATE_TXINIT,     CH_EVENT_UC_RCRESET, ch_action_txiniterr  },
	{ CH_STATE_TXINIT,     CH_EVENT_UC_RSRESET, ch_action_txiniterr  },
	{ CH_STATE_TXINIT,     CH_EVENT_TIMER,      ch_action_txiniterr  },
	{ CH_STATE_TXINIT,     CH_EVENT_IO_ENODEV,  ch_action_iofatal    },
	{ CH_STATE_TXINIT,     CH_EVENT_IO_EIO,     ch_action_iofatal    },
	{ CH_STATE_TXINIT,     CH_EVENT_MC_FAIL,    ch_action_fail       },

	{ CH_STATE_TXIDLE,     CH_EVENT_STOP,       ch_action_haltio     },
	{ CH_STATE_TXIDLE,     CH_EVENT_START,      fsm_action_nop       },
	{ CH_STATE_TXIDLE,     CH_EVENT_FINSTAT,    ch_action_firstio    },
	{ CH_STATE_TXIDLE,     CH_EVENT_UC_RCRESET, fsm_action_nop       },
	{ CH_STATE_TXIDLE,     CH_EVENT_UC_RSRESET, fsm_action_nop       },
	{ CH_STATE_TXIDLE,     CH_EVENT_IO_ENODEV,  ch_action_iofatal    },
	{ CH_STATE_TXIDLE,     CH_EVENT_IO_EIO,     ch_action_iofatal    },
	{ CH_STATE_TXIDLE,     CH_EVENT_MC_FAIL,    ch_action_fail       },

	{ CH_STATE_TERM,       CH_EVENT_STOP,       fsm_action_nop       },
	{ CH_STATE_TERM,       CH_EVENT_START,      ch_action_restart    },
	{ CH_STATE_TERM,       CH_EVENT_FINSTAT,    ch_action_stopped    },
	{ CH_STATE_TERM,       CH_EVENT_UC_RCRESET, fsm_action_nop       },
	{ CH_STATE_TERM,       CH_EVENT_UC_RSRESET, fsm_action_nop       },
	{ CH_STATE_TERM,       CH_EVENT_MC_FAIL,    ch_action_fail       },

	{ CH_STATE_DTERM,      CH_EVENT_STOP,       ch_action_haltio     },
	{ CH_STATE_DTERM,      CH_EVENT_START,      ch_action_restart    },
	{ CH_STATE_DTERM,      CH_EVENT_FINSTAT,    ch_action_setmode    },
	{ CH_STATE_DTERM,      CH_EVENT_UC_RCRESET, fsm_action_nop       },
	{ CH_STATE_DTERM,      CH_EVENT_UC_RSRESET, fsm_action_nop       },
	{ CH_STATE_DTERM,      CH_EVENT_MC_FAIL,    ch_action_fail       },

	{ CH_STATE_TX,         CH_EVENT_STOP,       ch_action_haltio     },
	{ CH_STATE_TX,         CH_EVENT_START,      fsm_action_nop       },
	{ CH_STATE_TX,         CH_EVENT_FINSTAT,    ch_action_txdone     },
	{ CH_STATE_TX,         CH_EVENT_UC_RCRESET, ch_action_txretry    },
	{ CH_STATE_TX,         CH_EVENT_UC_RSRESET, ch_action_txretry    },
	{ CH_STATE_TX,         CH_EVENT_TIMER,      ch_action_txretry    },
	{ CH_STATE_TX,         CH_EVENT_IO_ENODEV,  ch_action_iofatal    },
	{ CH_STATE_TX,         CH_EVENT_IO_EIO,     ch_action_iofatal    },
	{ CH_STATE_TX,         CH_EVENT_MC_FAIL,    ch_action_fail       },

	{ CH_STATE_RXERR,      CH_EVENT_STOP,       ch_action_haltio     },
	{ CH_STATE_TXERR,      CH_EVENT_STOP,       ch_action_haltio     },
	{ CH_STATE_TXERR,      CH_EVENT_MC_FAIL,    ch_action_fail       },
	{ CH_STATE_RXERR,      CH_EVENT_MC_FAIL,    ch_action_fail       },
};

static const int CH_FSM_LEN = sizeof(ch_fsm) / sizeof(fsm_node);

/**
 * Functions related to setup and device detection.
 *****************************************************************************/

/**
 * Add a new channel to the list of channels.
 * Keeps the channel list sorted.
 *
 * @param irq   The IRQ to be used by the new channel.
 * @param devno The device number of the new channel.
 * @param type  The type class of the new channel.
 *
 * @return 0 on success, !0 on error.
 */
static int add_channel(int irq, __u16 devno, channel_type_t type)
{
	channel **c = &channels;
	channel *ch;
	char name[10];

	if ((ch = (channel *)kmalloc(sizeof(channel), GFP_KERNEL)) == NULL) {
		printk(KERN_WARNING "ctc: Out of memory in add_channel\n");
		return -1;
	}
	memset(ch, 0, sizeof(channel));
	if ((ch->ccw = (ccw1_t *)kmalloc(sizeof(ccw1_t) * 8,
					 GFP_KERNEL|GFP_DMA)) == NULL) {
		kfree(ch);
		printk(KERN_WARNING "ctc: Out of memory in add_channel\n");
		return -1;
	}

	/**
	 * "static" ccws are used in the following way:
	 *
	 * ccw[0..2] (Channel program for generic I/O):
	 *           0: prepare
	 *           1: read or write (depending on direction) with fixed
	 *              buffer (idal allocated once when buffer is allocated)
	 *           2: nop
	 * ccw[3..5] (Channel program for direct write of packets)
	 *           3: prepare
	 *           4: write (idal allocated on every write).
	 *           5: nop
	 * ccw[6..7] (Channel program for initial channel setup):
	 *           3: set extended mode
	 *           4: nop
	 *
	 * ch->ccw[0..5] are initialized in ch_action_start because
	 * the channel's direction is yet unknown here.
	 */
	ch->ccw[6].cmd_code = CCW_CMD_SET_EXTENDED;
	ch->ccw[6].flags    = CCW_FLAG_SLI;
	ch->ccw[6].count    = 0;
	ch->ccw[6].cda      = 0;
	
	ch->ccw[7].cmd_code = CCW_CMD_NOOP;
	ch->ccw[7].flags    = CCW_FLAG_SLI;
	ch->ccw[7].count    = 0;
	ch->ccw[7].cda      = 0;

	ch->irq = irq;
	ch->devno = devno;
	ch->type = type;
	sprintf(name, "ch-%04x", devno);
	ch->fsm = init_fsm(name, ch_state_names,