C++ DECLARE_WAITQUEUE函数代码示例

static void mtd_ipanic_block_erase(void)
{
	struct mtd_ipanic_data *ctx = &mtd_drv_ctx;
	struct erase_info erase;
	DECLARE_WAITQUEUE(wait, current);
	wait_queue_head_t wait_q;
	int rc, i;

	init_waitqueue_head(&wait_q);
	erase.mtd = ctx->mtd;
	erase.callback = mtd_ipanic_block_erase_callback;
	erase.len = ctx->mtd->erasesize;
	erase.priv = (u_long)&wait_q;
	for (i = 0; i < ctx->mtd->size; i += ctx->mtd->erasesize) {
		erase.addr = i;
		set_current_state(TASK_INTERRUPTIBLE);
		add_wait_queue(&wait_q, &wait);

		rc = ctx->mtd->_block_isbad(ctx->mtd, erase.addr);
		if (rc < 0) {
			xlog_printk(ANDROID_LOG_ERROR, IPANIC_LOG_TAG,
			       "aee-ipanic: Bad block check "
			       "failed (%d)\n", rc);
			goto out;
		}
		if (rc) {
			xlog_printk(ANDROID_LOG_WARN, IPANIC_LOG_TAG,
			       "aee-ipanic: Skipping erase of bad "
			       "block @%llx\n", erase.addr);
			set_current_state(TASK_RUNNING);
			remove_wait_queue(&wait_q, &wait);
			continue;
		}

		rc = ctx->mtd->_erase(ctx->mtd, &erase);
		if (rc) {
			set_current_state(TASK_RUNNING);
			remove_wait_queue(&wait_q, &wait);
			xlog_printk(ANDROID_LOG_ERROR, IPANIC_LOG_TAG,
			       "aee-ipanic: Erase of 0x%llx, 0x%llx failed\n",
			       (unsigned long long) erase.addr,
			       (unsigned long long) erase.len);
			if (rc == -EIO) {
				if (ctx->mtd->_block_markbad(ctx->mtd,
							    erase.addr)) {
					xlog_printk(ANDROID_LOG_ERROR, IPANIC_LOG_TAG,
					       "aee-ipanic: Err marking blk bad\n");
					goto out;
				}
				xlog_printk(ANDROID_LOG_INFO, IPANIC_LOG_TAG,
				       "aee-ipanic: Marked a bad block"
				       " @%llx\n", erase.addr);
				continue;
			}
			goto out;
		}
		schedule();
		remove_wait_queue(&wait_q, &wait);
	}
	xlog_printk(ANDROID_LOG_DEBUG, IPANIC_LOG_TAG, "aee-ipanic: %s partition erased\n",
	       AEE_IPANIC_PLABEL);
out:
	return;
}

/**
 * n_hdlc_tty_write - write a single frame of data to device
 * @tty	- pointer to associated tty device instance data
 * @file - pointer to file object data
 * @data - pointer to transmit data (one frame)
 * @count - size of transmit frame in bytes
 * 		
 * Returns the number of bytes written (or error code).
 */
static ssize_t n_hdlc_tty_write(struct tty_struct *tty, struct file *file,
			    const unsigned char *data, size_t count)
{
	struct n_hdlc *n_hdlc = tty2n_hdlc (tty);
	int error = 0;
	DECLARE_WAITQUEUE(wait, current);
	struct n_hdlc_buf *tbuf;

	if (debuglevel >= DEBUG_LEVEL_INFO)	
		printk("%s(%d)n_hdlc_tty_write() called count=%zd\n",
			__FILE__,__LINE__,count);
		
	/* Verify pointers */
	if (!n_hdlc)
		return -EIO;

	if (n_hdlc->magic != HDLC_MAGIC)
		return -EIO;

	/* verify frame size */
	if (count > maxframe ) {
		if (debuglevel & DEBUG_LEVEL_INFO)
			printk (KERN_WARNING
				"n_hdlc_tty_write: truncating user packet "
				"from %lu to %d\n", (unsigned long) count,
				maxframe );
		count = maxframe;
	}
	
	add_wait_queue(&tty->write_wait, &wait);

	for (;;) {
		set_current_state(TASK_INTERRUPTIBLE);
	
		tbuf = n_hdlc_buf_get(&n_hdlc->tx_free_buf_list);
		if (tbuf)
			break;

		if (tty_io_nonblock(tty, file)) {
			error = -EAGAIN;
			break;
		}
		schedule();
			
		n_hdlc = tty2n_hdlc (tty);
		if (!n_hdlc || n_hdlc->magic != HDLC_MAGIC || 
		    tty != n_hdlc->tty) {
			printk("n_hdlc_tty_write: %p invalid after wait!\n", n_hdlc);
			error = -EIO;
			break;
		}
			
		if (signal_pending(current)) {
			error = -EINTR;
			break;
		}
	}

	__set_current_state(TASK_RUNNING);
	remove_wait_queue(&tty->write_wait, &wait);

	if (!error) {		
		/* Retrieve the user's buffer */
		memcpy(tbuf->buf, data, count);

		/* Send the data */
		tbuf->count = error = count;
		n_hdlc_buf_put(&n_hdlc->tx_buf_list,tbuf);
		n_hdlc_send_frames(n_hdlc,tty);
	}

	return error;
	
}	/* end of n_hdlc_tty_write() */

static ssize_t n_tty_read(struct tty_struct *tty, struct file *file,
			 unsigned char __user *buf, size_t nr)
{
	unsigned char __user *b = buf;
	DECLARE_WAITQUEUE(wait, current);
	int c;
	int minimum, time;
	ssize_t retval = 0;
	ssize_t size;
	long timeout;
	unsigned long flags;
	int packet;

do_it_again:

	if (WARN_ON(!tty->read_buf))
		return -EAGAIN;

	c = job_control(tty, file);
	if (c < 0)
		return c;

	minimum = time = 0;
	timeout = MAX_SCHEDULE_TIMEOUT;
	if (!tty->icanon) {
		time = (HZ / 10) * TIME_CHAR(tty);
		minimum = MIN_CHAR(tty);
		if (minimum) {
			if (time)
				tty->minimum_to_wake = 1;
			else if (!waitqueue_active(&tty->read_wait) ||
				 (tty->minimum_to_wake > minimum))
				tty->minimum_to_wake = minimum;
		} else {
			timeout = 0;
			if (time) {
				timeout = time;
				time = 0;
			}
			tty->minimum_to_wake = minimum = 1;
		}
	}

	if (file->f_flags & O_NONBLOCK) {
		if (!mutex_trylock(&tty->atomic_read_lock))
			return -EAGAIN;
	} else {
		if (mutex_lock_interruptible(&tty->atomic_read_lock))
			return -ERESTARTSYS;
	}
	packet = tty->packet;

	add_wait_queue(&tty->read_wait, &wait);
	while (nr) {
		
		if (packet && tty->link->ctrl_status) {
			unsigned char cs;
			if (b != buf)
				break;
			spin_lock_irqsave(&tty->link->ctrl_lock, flags);
			cs = tty->link->ctrl_status;
			tty->link->ctrl_status = 0;
			spin_unlock_irqrestore(&tty->link->ctrl_lock, flags);
			if (tty_put_user(tty, cs, b++)) {
				retval = -EFAULT;
				b--;
				break;
			}
			nr--;
			break;
		}
		set_current_state(TASK_INTERRUPTIBLE);

		if (((minimum - (b - buf)) < tty->minimum_to_wake) &&
		    ((minimum - (b - buf)) >= 1))
			tty->minimum_to_wake = (minimum - (b - buf));

		if (!input_available_p(tty, 0)) {
			if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) {
				retval = -EIO;
				break;
			}
			if (tty_hung_up_p(file))
				break;
			if (!timeout)
				break;
			if (file->f_flags & O_NONBLOCK) {
				retval = -EAGAIN;
				break;
			}
			if (signal_pending(current)) {
				retval = -ERESTARTSYS;
				break;
			}
			n_tty_set_room(tty);
			timeout = schedule_timeout(timeout);
			BUG_ON(!tty->read_buf);
			continue;
		}
		__set_current_state(TASK_RUNNING);
//.........这里部分代码省略.........

static int mtd_ioctl(struct inode *inode, struct file *file,
		     u_int cmd, u_long arg)
{
	struct mtd_info *mtd = (struct mtd_info *)file->private_data;
	int ret = 0;
	u_long size;
	
	DEBUG(MTD_DEBUG_LEVEL0, "MTD_ioctl\n");

	size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
	if (cmd & IOC_IN) {
		ret = verify_area(VERIFY_READ, (char *)arg, size);
		if (ret) return ret;
	}
	if (cmd & IOC_OUT) {
		ret = verify_area(VERIFY_WRITE, (char *)arg, size);
		if (ret) return ret;
	}
	
	switch (cmd) {
	case MEMGETREGIONCOUNT:
		if (copy_to_user((int *) arg, &(mtd->numeraseregions), sizeof(int)))
			return -EFAULT;
		break;

	case MEMGETREGIONINFO:
	{
		struct region_info_user ur;

		if (copy_from_user(	&ur, 
					(struct region_info_user *)arg, 
					sizeof(struct region_info_user))) {
			return -EFAULT;
		}

		if (ur.regionindex >= mtd->numeraseregions)
			return -EINVAL;
		if (copy_to_user((struct mtd_erase_region_info *) arg, 
				&(mtd->eraseregions[ur.regionindex]),
				sizeof(struct mtd_erase_region_info)))
			return -EFAULT;
		break;
	}

	case MEMGETINFO:
		if (copy_to_user((struct mtd_info *)arg, mtd,
				 sizeof(struct mtd_info_user)))
			return -EFAULT;
		break;

	case MEMERASE:
	{
		struct erase_info *erase=kmalloc(sizeof(struct erase_info),GFP_KERNEL);
		if (!erase)
			ret = -ENOMEM;
		else {
			wait_queue_head_t waitq;
			DECLARE_WAITQUEUE(wait, current);

			init_waitqueue_head(&waitq);

			memset (erase,0,sizeof(struct erase_info));
			if (copy_from_user(&erase->addr, (u_long *)arg,
					   2 * sizeof(u_long))) {
				kfree(erase);
				return -EFAULT;
			}
			erase->mtd = mtd;
			erase->callback = mtd_erase_callback;
			erase->priv = (unsigned long)&waitq;

			/*
			  FIXME: Allow INTERRUPTIBLE. Which means
			  not having the wait_queue head on the stack.
			  
			  If the wq_head is on the stack, and we
			  leave because we got interrupted, then the
			  wq_head is no longer there when the
			  callback routine tries to wake us up.
			*/
			ret = mtd->erase(mtd, erase);
			if (!ret) {
				set_current_state(TASK_UNINTERRUPTIBLE);
				add_wait_queue(&waitq, &wait);
				if (erase->state != MTD_ERASE_DONE &&
				    erase->state != MTD_ERASE_FAILED)
					schedule();
				remove_wait_queue(&waitq, &wait);
				set_current_state(TASK_RUNNING);

				ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
			}
			kfree(erase);
		}
		break;
	}

	case MEMWRITEOOB:
	{
		struct mtd_oob_buf buf;
//.........这里部分代码省略.........

int cx18_stop_v4l2_encode_stream(struct cx18_stream *s, int gop_end)
{
	struct cx18 *cx = s->cx;
	unsigned long then;

	if (!cx18_stream_enabled(s))
		return -EINVAL;

	/* This function assumes that you are allowed to stop the capture
	   and that we are actually capturing */

	CX18_DEBUG_INFO("Stop Capture\n");

	if (atomic_read(&cx->tot_capturing) == 0)
		return 0;

	set_bit(CX18_F_S_STOPPING, &s->s_flags);
	if (s->type == CX18_ENC_STREAM_TYPE_MPG)
		cx18_vapi(cx, CX18_CPU_CAPTURE_STOP, 2, s->handle, !gop_end);
	else
		cx18_vapi(cx, CX18_CPU_CAPTURE_STOP, 1, s->handle);

	then = jiffies;

	if (s->type == CX18_ENC_STREAM_TYPE_MPG && gop_end) {
#if 0
		/* only run these if we're shutting down the last cap */
		DECLARE_WAITQUEUE(wait, current);
		unsigned long duration;

		then = jiffies;
		add_wait_queue(&cx->cap_w, &wait);

		set_current_state(TASK_INTERRUPTIBLE);

		/* TODO: wait 2s for EOS interrupt */
		while (!test_bit(CX18_F_I_EOS, &cx->i_flags) &&
		       time_before(jiffies, then + msecs_to_jiffies(2000)))
			schedule_timeout(msecs_to_jiffies(10));

		duration = jiffies_to_msecs(jiffies - then);

		if (!test_bit(CX18_F_I_EOS, &cx->i_flags)) {
			CX18_DEBUG_WARN("%s: EOS interrupt not received! stopping anyway.\n", s->name);
			CX18_DEBUG_WARN("%s: waited %lu ms.\n", s->name, duration);
		} else {
			CX18_DEBUG_INFO("%s: EOS took %lu ms to occur.\n", s->name, duration);
		}
		set_current_state(TASK_RUNNING);
		remove_wait_queue(&cx->cap_w, &wait);
#else
		CX18_INFO("ignoring gop_end: not (yet?) supported by the firmware\n");
#endif
	}

	if (s->type != CX18_ENC_STREAM_TYPE_TS)
		atomic_dec(&cx->ana_capturing);
	atomic_dec(&cx->tot_capturing);

	/* Clear capture and no-read bits */
	clear_bit(CX18_F_S_STREAMING, &s->s_flags);

	/* Tell the CX23418 it can't use our buffers anymore */
	cx18_vapi(cx, CX18_CPU_DE_RELEASE_MDL, 1, s->handle);

	cx18_vapi(cx, CX18_DESTROY_TASK, 1, s->handle);
	s->handle = CX18_INVALID_TASK_HANDLE;
	clear_bit(CX18_F_S_STOPPING, &s->s_flags);

	if (atomic_read(&cx->tot_capturing) > 0)
		return 0;

	cx18_write_reg(cx, 5, CX18_DSP0_INTERRUPT_MASK);
	wake_up(&s->waitq);

	return 0;
}

/*
========================================================================
Routine Description:
    Close raxx interface.

Arguments:
	*net_dev			the raxx interface pointer

Return Value:
    0					Open OK
	otherwise			Open Fail

Note:
	1. if open fail, kernel will not call the close function.
	2. Free memory for
		(1) Mlme Memory Handler:		MlmeHalt()
		(2) TX & RX:					RTMPFreeTxRxRingMemory()
		(3) BA Reordering: 				ba_reordering_resource_release()
========================================================================
*/
int rt28xx_close(struct net_device *dev)
{
	struct net_device *net_dev = (struct net_device *)dev;
	struct rt_rtmp_adapter *pAd = NULL;
	BOOLEAN Cancelled;
	u32 i = 0;

#ifdef RTMP_MAC_USB
	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(unlink_wakeup);
	DECLARE_WAITQUEUE(wait, current);
#endif /* RTMP_MAC_USB // */

	GET_PAD_FROM_NET_DEV(pAd, net_dev);

	DBGPRINT(RT_DEBUG_TRACE, ("===> rt28xx_close\n"));

	Cancelled = FALSE;
	/* Sanity check for pAd */
	if (pAd == NULL)
		return 0;	/* close ok */

	{
#ifdef RTMP_MAC_PCI
		RTMPPCIeLinkCtrlValueRestore(pAd, RESTORE_CLOSE);
#endif /* RTMP_MAC_PCI // */

		/* If dirver doesn't wake up firmware here, */
		/* NICLoadFirmware will hang forever when interface is up again. */
		if (OPSTATUS_TEST_FLAG(pAd, fOP_STATUS_DOZE)) {
			AsicForceWakeup(pAd, TRUE);
		}
#ifdef RTMP_MAC_USB
		RTMP_SET_FLAG(pAd, fRTMP_ADAPTER_REMOVE_IN_PROGRESS);
#endif /* RTMP_MAC_USB // */

		MlmeRadioOff(pAd);
#ifdef RTMP_MAC_PCI
		pAd->bPCIclkOff = FALSE;
#endif /* RTMP_MAC_PCI // */
	}

	RTMP_SET_FLAG(pAd, fRTMP_ADAPTER_HALT_IN_PROGRESS);

	for (i = 0; i < NUM_OF_TX_RING; i++) {
		while (pAd->DeQueueRunning[i] == TRUE) {
			DBGPRINT(RT_DEBUG_TRACE,
				 ("Waiting for TxQueue[%d] done..........\n",
				  i));
			RTMPusecDelay(1000);
		}
	}

#ifdef RTMP_MAC_USB
	/* ensure there are no more active urbs. */
	add_wait_queue(&unlink_wakeup, &wait);
	pAd->wait = &unlink_wakeup;

	/* maybe wait for deletions to finish. */
	i = 0;
	/*while((i < 25) && atomic_read(&pAd->PendingRx) > 0) */
	while (i < 25) {
		unsigned long IrqFlags;

		RTMP_IRQ_LOCK(&pAd->BulkInLock, IrqFlags);
		if (pAd->PendingRx == 0) {
			RTMP_IRQ_UNLOCK(&pAd->BulkInLock, IrqFlags);
			break;
		}
		RTMP_IRQ_UNLOCK(&pAd->BulkInLock, IrqFlags);

		msleep(UNLINK_TIMEOUT_MS);	/*Time in millisecond */
		i++;
	}
	pAd->wait = NULL;
	remove_wait_queue(&unlink_wakeup, &wait);
#endif /* RTMP_MAC_USB // */

	/* Stop Mlme state machine */
	MlmeHalt(pAd);

//.........这里部分代码省略.........

int hsi_proto_read(int ch, u32 *buffer, int count)
{
	DECLARE_WAITQUEUE(wait, current);
	u32 *data;
	unsigned int data_len = 0;
	struct protocol_queue *entry;
	int ret, recv_data = 0;

	/*if (count > MAX_HSI_IPC_BUFFER)
		count = MAX_HSI_IPC_BUFFER;

	data = kmalloc(count, GFP_ATOMIC);*/

	ret = if_hsi_read(ch, buffer, count);
	if (ret < 0) {
		pr_err("Can not submit read. READ Error\n");
		goto out2;
	}

	spin_lock_bh(&hsi_protocol_data[ch].lock);
	add_wait_queue(&hsi_protocol_data[ch].rx_wait, &wait);
	spin_unlock_bh(&hsi_protocol_data[ch].lock);

	for (;;) {
		data = NULL;
		data_len = 0;

		set_current_state(TASK_INTERRUPTIBLE);

		spin_lock_bh(&hsi_protocol_data[ch].lock);
		if (!list_empty(&hsi_protocol_data[ch].rx_queue)) {
			entry = list_entry(hsi_protocol_data[ch].rx_queue.next,
					   struct protocol_queue, list);
			data = entry->data;
			data_len = entry->count;
			list_del(&entry->list);
			kfree(entry);
		}
		spin_unlock_bh(&hsi_protocol_data[ch].lock);

		pr_debug("%s, data = 0x%p, data_len = %d\n",
			 __func__, data, data_len);

		if (data_len) {
			pr_debug("%s, RX finished, ch-> %d, length = %d\n",
				__func__, ch, count);
			spin_lock_bh(&hsi_protocol_data[ch].lock);
			hsi_protocol_data[ch].poll_event &=
							~(POLLIN | POLLRDNORM);
			spin_unlock_bh(&hsi_protocol_data[ch].lock);
			if_hsi_poll(ch);
#if 0
			memcpy(buffer, data, count);
#endif
			recv_data += data_len;
#if 0
			buffer += data_len;
			if ((recv_data == count) || (recv_data >= MAX_HSI_IPC_BUFFER))
#endif
			break;
		} else if (signal_pending(current)) {
			pr_debug("%s, ERESTARTSYS\n", __func__);
			recv_data = -EAGAIN;
			if_hsi_cancel_read(ch);
			/* goto out; */
			break;
		}

		/*printk(KERN_DEBUG "%s, going to sleep...\n", __func__); */
		schedule();
		/*printk(KERN_DEBUG "%s, woke up\n", __func__); */
	}

/*
========================================================================
Routine Description:
    Close raxx interface.

Arguments:
	*net_dev			the raxx interface pointer

Return Value:
    0					Open OK
	otherwise			Open Fail

Note:
	1. if open fail, kernel will not call the close function.
	2. Free memory for
		(1) Mlme Memory Handler:		MlmeHalt()
		(2) TX & RX:					RTMPFreeTxRxRingMemory()
		(3) BA Reordering: 				ba_reordering_resource_release()
========================================================================
*/
int rt28xx_close(IN PNET_DEV dev)
{
	struct net_device * net_dev = (struct net_device *)dev;
    RTMP_ADAPTER	*pAd = RTMP_OS_NETDEV_GET_PRIV(net_dev);
	BOOLEAN 		Cancelled;
	UINT32			i = 0;
#ifdef RTMP_MAC_USB
	DECLARE_WAIT_QUEUE_HEAD(unlink_wakeup); 
	DECLARE_WAITQUEUE(wait, current);

	//RTMP_SET_FLAG(pAd, fRTMP_ADAPTER_REMOVE_IN_PROGRESS);
#endif // RTMP_MAC_USB //


	DBGPRINT(RT_DEBUG_TRACE, ("===> rt28xx_close\n"));

	Cancelled = FALSE;
	// Sanity check for pAd
	if (pAd == NULL)
		return 0; // close ok



#ifdef WDS_SUPPORT
	WdsDown(pAd);
#endif // WDS_SUPPORT //

#ifdef CONFIG_STA_SUPPORT
	IF_DEV_CONFIG_OPMODE_ON_STA(pAd)
	{

		// If dirver doesn't wake up firmware here,
		// NICLoadFirmware will hang forever when interface is up again.
		if (OPSTATUS_TEST_FLAG(pAd, fOP_STATUS_DOZE))
        {      
		    AsicForceWakeup(pAd, TRUE);
        }

#ifdef RTMP_MAC_USB
	RTMP_SET_FLAG(pAd, fRTMP_ADAPTER_REMOVE_IN_PROGRESS);
#endif // RTMP_MAC_USB //

		MlmeRadioOff(pAd);
	}
#endif // CONFIG_STA_SUPPORT //

	RTMP_SET_FLAG(pAd, fRTMP_ADAPTER_HALT_IN_PROGRESS);

	for (i = 0 ; i < NUM_OF_TX_RING; i++)
	{
		while (pAd->DeQueueRunning[i] == TRUE)
		{
			DBGPRINT(RT_DEBUG_TRACE, ("Waiting for TxQueue[%d] done..........\n", i));
			RTMPusecDelay(1000);
		}
	}
	
#ifdef RTMP_MAC_USB
	// ensure there are no more active urbs.
	add_wait_queue (&unlink_wakeup, &wait);
	pAd->wait = &unlink_wakeup;

	// maybe wait for deletions to finish.
	i = 0;
	//while((i < 25) && atomic_read(&pAd->PendingRx) > 0) 
	while(i < 25)
	{
		unsigned long IrqFlags;

		RTMP_IRQ_LOCK(&pAd->BulkInLock, IrqFlags);
		if (pAd->PendingRx == 0)
		{
			RTMP_IRQ_UNLOCK(&pAd->BulkInLock, IrqFlags);
			break;
		}
		RTMP_IRQ_UNLOCK(&pAd->BulkInLock, IrqFlags);
		
#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,9)
		msleep(UNLINK_TIMEOUT_MS);	//Time in millisecond
#else
//.........这里部分代码省略.........

/*
 * AFS Cache Manager kernel thread
 */
static int kafscmd(void *arg)
{
	DECLARE_WAITQUEUE(myself, current);

	struct rxrpc_call *call;
	_SRXAFSCM_xxxx_t func;
	int die;

	printk("kAFS: Started kafscmd %d\n", current->pid);

	daemonize("kafscmd");

	complete(&kafscmd_alive);

	/* loop around looking for things to attend to */
	do {
		if (list_empty(&kafscmd_attention_list)) {
			set_current_state(TASK_INTERRUPTIBLE);
			add_wait_queue(&kafscmd_sleepq, &myself);

			for (;;) {
				set_current_state(TASK_INTERRUPTIBLE);
				if (!list_empty(&kafscmd_attention_list) ||
				    signal_pending(current) ||
				    kafscmd_die)
					break;

				schedule();
			}

			remove_wait_queue(&kafscmd_sleepq, &myself);
			set_current_state(TASK_RUNNING);
		}

		die = kafscmd_die;

		/* dequeue the next call requiring attention */
		call = NULL;
		spin_lock(&kafscmd_attention_lock);

		if (!list_empty(&kafscmd_attention_list)) {
			call = list_entry(kafscmd_attention_list.next,
					  struct rxrpc_call,
					  app_attn_link);
			list_del_init(&call->app_attn_link);
			die = 0;
		}

		spin_unlock(&kafscmd_attention_lock);

		if (call) {
			/* act upon it */
			_debug("@@@ Begin Attend Call %p", call);

			func = call->app_user;
			if (func)
				func(call);

			rxrpc_put_call(call);

			_debug("@@@ End Attend Call %p", call);
		}

	} while(!die);

int gs_block_til_ready(void *port_, struct file * filp)
{
	struct gs_port *gp = port_;
	struct tty_port *port = &gp->port;
	DECLARE_WAITQUEUE(wait, current);
	int    retval;
	int    do_clocal = 0;
	int    CD;
	struct tty_struct *tty;
	unsigned long flags;

	func_enter ();

	if (!port) return 0;

	tty = port->tty;

	gs_dprintk (GS_DEBUG_BTR, "Entering gs_block_till_ready.\n"); 
	/*
	 * If the device is in the middle of being closed, then block
	 * until it's done, and then try again.
	 */
	if (tty_hung_up_p(filp) || port->flags & ASYNC_CLOSING) {
		interruptible_sleep_on(&port->close_wait);
		if (port->flags & ASYNC_HUP_NOTIFY)
			return -EAGAIN;
		else
			return -ERESTARTSYS;
	}

	gs_dprintk (GS_DEBUG_BTR, "after hung up\n"); 

	/*
	 * If non-blocking mode is set, or the port is not enabled,
	 * then make the check up front and then exit.
	 */
	if ((filp->f_flags & O_NONBLOCK) ||
	    (tty->flags & (1 << TTY_IO_ERROR))) {
		port->flags |= ASYNC_NORMAL_ACTIVE;
		return 0;
	}

	gs_dprintk (GS_DEBUG_BTR, "after nonblock\n"); 
 
	if (C_CLOCAL(tty))
		do_clocal = 1;

	/*
	 * Block waiting for the carrier detect and the line to become
	 * free (i.e., not in use by the callout).  While we are in
	 * this loop, port->count is dropped by one, so that
	 * rs_close() knows when to free things.  We restore it upon
	 * exit, either normal or abnormal.
	 */
	retval = 0;

	add_wait_queue(&port->open_wait, &wait);

	gs_dprintk (GS_DEBUG_BTR, "after add waitq.\n"); 
	spin_lock_irqsave(&port->lock, flags);
	if (!tty_hung_up_p(filp)) {
		port->count--;
	}
	port->blocked_open++;
	spin_unlock_irqrestore(&port->lock, flags);
	while (1) {
		CD = tty_port_carrier_raised(port);
		gs_dprintk (GS_DEBUG_BTR, "CD is now %d.\n", CD);
		set_current_state (TASK_INTERRUPTIBLE);
		if (tty_hung_up_p(filp) ||
		    !(port->flags & ASYNC_INITIALIZED)) {
			if (port->flags & ASYNC_HUP_NOTIFY)
				retval = -EAGAIN;
			else
				retval = -ERESTARTSYS;
			break;
		}
		if (!(port->flags & ASYNC_CLOSING) &&
		    (do_clocal || CD))
			break;
		gs_dprintk (GS_DEBUG_BTR, "signal_pending is now: %d (%lx)\n", 
		(int)signal_pending (current), *(long*)(&current->blocked)); 
		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
		schedule();
	}
	gs_dprintk (GS_DEBUG_BTR, "Got out of the loop. (%d)\n",
		    port->blocked_open);
	set_current_state (TASK_RUNNING);
	remove_wait_queue(&port->open_wait, &wait);
	
	spin_lock_irqsave(&port->lock, flags);
	if (!tty_hung_up_p(filp)) {
		port->count++;
	}
	port->blocked_open--;
	if (retval == 0)
        	port->flags |= ASYNC_NORMAL_ACTIVE;
//.........这里部分代码省略.........

/*
 * fetch file status from the volume
 * - don't issue a fetch if:
 *   - the changed bit is not set and there's a valid callback
 *   - there are any outstanding ops that will fetch the status
 * - TODO implement local caching
 */
int afs_vnode_fetch_status(struct afs_vnode *vnode,
			   struct afs_vnode *auth_vnode, struct key *key)
{
	struct afs_server *server;
	unsigned long acl_order;
	int ret;

	DECLARE_WAITQUEUE(myself, current);

	_enter("%s,{%x:%u.%u}",
	       vnode->volume->vlocation->vldb.name,
	       vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique);

	if (!test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags) &&
	    vnode->cb_promised) {
		_leave(" [unchanged]");
		return 0;
	}

	if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
		_leave(" [deleted]");
		return -ENOENT;
	}

	acl_order = 0;
	if (auth_vnode)
		acl_order = auth_vnode->acl_order;

	spin_lock(&vnode->lock);

	if (!test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags) &&
	    vnode->cb_promised) {
		spin_unlock(&vnode->lock);
		_leave(" [unchanged]");
		return 0;
	}

	ASSERTCMP(vnode->update_cnt, >=, 0);

	if (vnode->update_cnt > 0) {
		/* someone else started a fetch */
		_debug("wait on fetch %d", vnode->update_cnt);

		set_current_state(TASK_UNINTERRUPTIBLE);
		ASSERT(myself.func != NULL);
		add_wait_queue(&vnode->update_waitq, &myself);

		/* wait for the status to be updated */
		for (;;) {
			if (!test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags))
				break;
			if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
				break;

			/* check to see if it got updated and invalidated all
			 * before we saw it */
			if (vnode->update_cnt == 0) {
				remove_wait_queue(&vnode->update_waitq,
						  &myself);
				set_current_state(TASK_RUNNING);
				goto get_anyway;
			}

			spin_unlock(&vnode->lock);

			schedule();
			set_current_state(TASK_UNINTERRUPTIBLE);

			spin_lock(&vnode->lock);
		}

		remove_wait_queue(&vnode->update_waitq, &myself);
		spin_unlock(&vnode->lock);
		set_current_state(TASK_RUNNING);

		return test_bit(AFS_VNODE_DELETED, &vnode->flags) ?
			-ENOENT : 0;
	}

get_anyway:
	/* okay... we're going to have to initiate the op */
	vnode->update_cnt++;

	spin_unlock(&vnode->lock);

	/* merge AFS status fetches and clear outstanding callback on this
	 * vnode */
	do {
		/* pick a server to query */
		server = afs_volume_pick_fileserver(vnode);
		if (IS_ERR(server))
			goto no_server;

//.........这里部分代码省略.........

/* n_hdlc_tty_write()
 * 
 * 	write a single frame of data to device
 * 	
 * Arguments:	tty	pointer to associated tty device instance data
 * 		file	pointer to file object data
 * 		data	pointer to transmit data (one frame)
 * 		count	size of transmit frame in bytes
 * 		
 * Return Value:	number of bytes written (or error code)
 */
static rw_ret_t n_hdlc_tty_write (struct tty_struct *tty, struct file *file,
	const __u8 * data, rw_count_t count)
{
	struct n_hdlc *n_hdlc = tty2n_hdlc (tty);
	int error = 0;
	DECLARE_WAITQUEUE(wait, current);
	N_HDLC_BUF *tbuf;

	if (debuglevel >= DEBUG_LEVEL_INFO)	
		printk("%s(%d)n_hdlc_tty_write() called count=%d\n",
			__FILE__,__LINE__,count);
		
	/* Verify pointers */
	if (!n_hdlc)
		return -EIO;

	if (n_hdlc->magic != HDLC_MAGIC)
		return -EIO;

	/* verify frame size */
	if (count > maxframe ) {
		if (debuglevel & DEBUG_LEVEL_INFO)
			printk (KERN_WARNING
				"n_hdlc_tty_write: truncating user packet "
				"from %lu to %d\n", (unsigned long) count,
				maxframe );
		count = maxframe;
	}
	
	add_wait_queue(&n_hdlc->write_wait, &wait);
	set_current_state(TASK_INTERRUPTIBLE);
	
	/* Allocate transmit buffer */
	/* sleep until transmit buffer available */		
	while (!(tbuf = n_hdlc_buf_get(&n_hdlc->tx_free_buf_list))) {
		schedule();
			
		n_hdlc = tty2n_hdlc (tty);
		if (!n_hdlc || n_hdlc->magic != HDLC_MAGIC || 
		    tty != n_hdlc->tty) {
			printk("n_hdlc_tty_write: %p invalid after wait!\n", n_hdlc);
			error = -EIO;
			break;
		}
			
		if (signal_pending(current)) {
			error = -EINTR;
			break;
		}
	}

	set_current_state(TASK_RUNNING);
	remove_wait_queue(&n_hdlc->write_wait, &wait);

	if (!error) {		
		/* Retrieve the user's buffer */
		COPY_FROM_USER (error, tbuf->buf, data, count);
		if (error) {
			/* return tx buffer to free list */
			n_hdlc_buf_put(&n_hdlc->tx_free_buf_list,tbuf);
		} else {
			/* Send the data */
			tbuf->count = error = count;
			n_hdlc_buf_put(&n_hdlc->tx_buf_list,tbuf);
			n_hdlc_send_frames(n_hdlc,tty);
		}
	}

	return error;
	
}	/* end of n_hdlc_tty_write() */

static void ad1889_update_ptr(ad1889_dev_t *dev, int wake)
{
	ad1889_state_t *state;
	struct dmabuf *dmabuf;
	unsigned long hwptr;
	int diff;

	/* check ADC first */
	state = &dev->adc_state;
	dmabuf = &state->dmabuf;
	if (dmabuf->enable & ADC_RUNNING) {
		hwptr = ad1889_get_dma_addr(state);
		diff = (dmabuf->dmasize + hwptr - dmabuf->hwptr) % dmabuf->dmasize;

		dmabuf->hwptr = hwptr;
		dmabuf->total_bytes += diff;
		dmabuf->count += diff;
		if (dmabuf->count > dmabuf->dmasize)
			dmabuf->count = dmabuf->dmasize;

		if (dmabuf->mapped) {
			if (wake & dmabuf->count >= dmabuf->fragsize)
				wake_up(&dmabuf->wait);
		} else {
			if (wake & dmabuf->count > 0)
				wake_up(&dmabuf->wait);
		}
	}

	/* check DAC */
	state = &dev->wav_state;
	dmabuf = &state->dmabuf;
	if (dmabuf->enable & DAC_RUNNING) {
XXX

}
#endif

/************************* /dev/dsp interfaces ************************* */

static ssize_t ad1889_read(struct file *file, char __user *buffer, size_t count,
	loff_t *ppos)
{
	return 0;
}

static ssize_t ad1889_write(struct file *file, const char __user *buffer, size_t count,
	loff_t *ppos)
{
	ad1889_dev_t *dev = (ad1889_dev_t *)file->private_data;
	ad1889_state_t *state = &dev->state[AD_WAV_STATE];
	volatile struct dmabuf *dmabuf = &state->dmabuf;
	ssize_t ret = 0;
	DECLARE_WAITQUEUE(wait, current);

	mutex_lock(&state->mutex);
#if 0
	if (dmabuf->mapped) {
		ret = -ENXIO;
		goto err1;
	}
#endif
	if (!access_ok(VERIFY_READ, buffer, count)) {
		ret = -EFAULT;
		goto err1;
	}

	add_wait_queue(&state->dmabuf.wait, &wait);

	/* start filling dma buffer.... */
	while (count > 0) {
		long rem;
		long cnt = count;
		unsigned long flags;

		for (;;) {
			long used_bytes;
			long timeout;	/* max time for DMA in jiffies */

			/* buffer is full if wr catches up to rd */
			spin_lock_irqsave(&state->card->lock, flags);
			used_bytes = dmabuf->wr_ptr - dmabuf->rd_ptr;
			timeout = (dmabuf->dma_len * HZ) / dmabuf->rate;
			spin_unlock_irqrestore(&state->card->lock, flags);

			/* adjust for buffer wrap around */
			used_bytes = (used_bytes + DMA_SIZE) & (DMA_SIZE - 1);

			/* If at least one page unused */
			if (used_bytes < (DMA_SIZE - 0x1000))
				break;

			/* dma buffer full */

			if (file->f_flags & O_NONBLOCK) {
				ret = -EAGAIN;
				goto err2;
			}

			set_current_state(TASK_INTERRUPTIBLE);
//.........这里部分代码省略.........

int netlink_unicast(struct sock *ssk, struct sk_buff *skb, u32 pid, int nonblock)
{
	struct sock *sk;
	int len = skb->len;
	int protocol = ssk->protocol;
	long timeo;
        DECLARE_WAITQUEUE(wait, current);

	timeo = sock_sndtimeo(ssk, nonblock);

retry:
	sk = netlink_lookup(protocol, pid);
	if (sk == NULL)
		goto no_dst;

	/* Don't bother queuing skb if kernel socket has no input function */
	if (sk->protinfo.af_netlink->pid == 0 &&
	    !sk->protinfo.af_netlink->data_ready)
		goto no_dst;

#ifdef NL_EMULATE_DEV
	if (sk->protinfo.af_netlink->handler) {
		skb_orphan(skb);
		len = sk->protinfo.af_netlink->handler(protocol, skb);
		sock_put(sk);
		return len;
	}
#endif

	if (atomic_read(&sk->rmem_alloc) > sk->rcvbuf ||
	    test_bit(0, &sk->protinfo.af_netlink->state)) {
		if (!timeo) {
			if (ssk->protinfo.af_netlink->pid == 0)
				netlink_overrun(sk);
			sock_put(sk);
			kfree_skb(skb);
			return -EAGAIN;
		}

		__set_current_state(TASK_INTERRUPTIBLE);
		add_wait_queue(&sk->protinfo.af_netlink->wait, &wait);

		if ((atomic_read(&sk->rmem_alloc) > sk->rcvbuf ||
		    test_bit(0, &sk->protinfo.af_netlink->state)) &&
		    !sk->dead)
			timeo = schedule_timeout(timeo);

		__set_current_state(TASK_RUNNING);
		remove_wait_queue(&sk->protinfo.af_netlink->wait, &wait);
		sock_put(sk);

		if (signal_pending(current)) {
			kfree_skb(skb);
			return sock_intr_errno(timeo);
		}
		goto retry;
	}

	skb_orphan(skb);
	skb_set_owner_r(skb, sk);
	skb_queue_tail(&sk->receive_queue, skb);
	sk->data_ready(sk, len);
	sock_put(sk);
	return len;

no_dst:
	kfree_skb(skb);
	return -ECONNREFUSED;
}

static int usb_rtusb_close_device(
	IN	PRTMP_ADAPTER	pAd)
{
	int i = 0;
	int ret;
	
	DECLARE_WAIT_QUEUE_HEAD (unlink_wakeup); 
	DECLARE_WAITQUEUE (wait, current);

	DBGPRINT(RT_DEBUG_TRACE, "-->usb_rtusb_close_device \n");

	// ensure there are no more active urbs. 
	add_wait_queue (&unlink_wakeup, &wait);
	pAd->wait = &unlink_wakeup;

	// maybe wait for deletions to finish.
	while ((i < 25) && atomic_read(&pAd->PendingRx) > 0)
	{
#if LINUX_VERSION_CODE >KERNEL_VERSION(2,6,9)
		msleep(UNLINK_TIMEOUT_MS);
#endif
		i++;
	}

	pAd->wait = NULL;
	remove_wait_queue (&unlink_wakeup, &wait); 

	if (pAd->MLMEThr_pid >= 0) 
	{
		mlme_kill = 1;
		RTUSBMlmeUp(pAd);
		wmb(); // need to check
		ret = KILL_THREAD_PID (pAd->MLMEThr_pid, SIGTERM, 1);
		if (ret) 
		{
			printk (KERN_WARNING "%s: unable to Mlme thread \n", pAd->net_dev->name);
		}
		wait_for_completion (&pAd->MlmeThreadNotify);
		// reset mlme thread
		pAd->MLMEThr_pid = THREAD_PID_INIT_VALUE;
	}

	if (pAd->RTUSBCmdThr_pid>= 0) 
	{
		RTUSBCmd_kill = 1;
		RTUSBCMDUp(pAd);
		wmb(); // need to check
		ret = KILL_THREAD_PID (pAd->RTUSBCmdThr_pid, SIGTERM, 1);
		if (ret) 
		{
			printk (KERN_WARNING "%s: unable to RTUSBCmd thread \n", pAd->net_dev->name);
		}
		wait_for_completion (&pAd->CmdThreadNotify);
		// reset cmd thread
		pAd->RTUSBCmdThr_pid= THREAD_PID_INIT_VALUE;
	}

	RTUSBHalt(pAd, TRUE);
	RTMP_SET_FLAG(pAd, fRTMP_ADAPTER_REMOVE_IN_PROGRESS);
	tasklet_kill(&pAd->rx_bh);



	DBGPRINT(RT_DEBUG_TRACE,"<--usb_rtusb_close_device \n");

	return 0;
}