Commit fb4b4881 authored by Jan Kiszka's avatar Jan Kiszka Committed by David S. Miller
Browse files

CAPI: Use tty_port to keep track of capiminor's tty 



Use the reference management features of tty_port to look up and drop
again the tty_struct associated with a capiminor.

Signed-off-by: default avatarJan Kiszka <jan.kiszka@web.de>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 46324511

drivers/isdn/capi/capi.c

+62 −32
Original line number Diff line number Diff line
@@ -94,7 +94,7 @@ struct capiminor { 
	u16		 datahandle;

	u16		 msgid;



	struct tty_struct *tty;

	struct tty_port port;

	int                ttyinstop;

	int                ttyoutstop;

	struct sk_buff    *ttyskb;
@@ -212,6 +212,8 @@ static void capiminor_del_all_ack(struct capiminor *mp) 


/* -------- struct capiminor ---------------------------------------- */



static const struct tty_port_operations capiminor_port_ops; /* we have none */



static struct capiminor *capiminor_alloc(struct capi20_appl *ap, u32 ncci)

{

	struct capiminor *mp;
@@ -237,6 +239,9 @@ static struct capiminor *capiminor_alloc(struct capi20_appl *ap, u32 ncci) 
	skb_queue_head_init(&mp->inqueue);

	skb_queue_head_init(&mp->outqueue);



	tty_port_init(&mp->port);

	mp->port.ops = &capiminor_port_ops;



	/* Allocate the least unused minor number. */

	write_lock_irqsave(&capiminors_lock, flags);

	for (minor = 0; minor < capi_ttyminors; minor++)
@@ -335,18 +340,22 @@ static void capincci_alloc_minor(struct capidev *cdev, struct capincci *np) 
static void capincci_free_minor(struct capincci *np)

{

	struct capiminor *mp = np->minorp;

	struct tty_struct *tty;



	if (mp) {

		capifs_free_ncci(mp->capifs_dentry);

		if (mp->tty) {



		tty = tty_port_tty_get(&mp->port);

		if (tty) {

			mp->nccip = NULL;

#ifdef _DEBUG_REFCOUNT

			printk(KERN_DEBUG "reset mp->nccip\n");

#endif

			tty_hangup(mp->tty);

		} else {

			capiminor_free(mp);

			tty_hangup(tty);

			tty_kref_put(tty);

		}



		capiminor_free(mp);

	}

}
@@ -433,44 +442,48 @@ gen_data_b3_resp_for(struct capiminor *mp, struct sk_buff *skb) 


static int handle_recv_skb(struct capiminor *mp, struct sk_buff *skb)

{

	struct tty_struct *tty;

	struct sk_buff *nskb;

	int datalen;

	u16 errcode, datahandle;

	struct tty_ldisc *ld;

	int ret = -1;



	datalen = skb->len - CAPIMSG_LEN(skb->data);

	if (mp->tty == NULL)

	{



	tty = tty_port_tty_get(&mp->port);

	if (!tty) {

#ifdef _DEBUG_DATAFLOW

		printk(KERN_DEBUG "capi: currently no receiver\n");

#endif

		return -1;

	}

	

	ld = tty_ldisc_ref(mp->tty);

	if (ld == NULL)

		return -1;

	ld = tty_ldisc_ref(tty);

	if (!ld)

		goto out1;



	if (ld->ops->receive_buf == NULL) {

#if defined(_DEBUG_DATAFLOW) || defined(_DEBUG_TTYFUNCS)

		printk(KERN_DEBUG "capi: ldisc has no receive_buf function\n");

#endif

		goto bad;

		goto out2;

	}

	if (mp->ttyinstop) {

#if defined(_DEBUG_DATAFLOW) || defined(_DEBUG_TTYFUNCS)

		printk(KERN_DEBUG "capi: recv tty throttled\n");

#endif

		goto bad;

		goto out2;

	}

	if (mp->tty->receive_room < datalen) {

	if (tty->receive_room < datalen) {

#if defined(_DEBUG_DATAFLOW) || defined(_DEBUG_TTYFUNCS)

		printk(KERN_DEBUG "capi: no room in tty\n");

#endif

		goto bad;

		goto out2;

	}

	if ((nskb = gen_data_b3_resp_for(mp, skb)) == NULL) {

		printk(KERN_ERR "capi: gen_data_b3_resp failed\n");

		goto bad;

		goto out2;

	}

	datahandle = CAPIMSG_U16(skb->data,CAPIMSG_BASELEN+4);

	errcode = capi20_put_message(mp->ap, nskb);
@@ -478,20 +491,21 @@ static int handle_recv_skb(struct capiminor *mp, struct sk_buff *skb) 
		printk(KERN_ERR "capi: send DATA_B3_RESP failed=%x\n",

				errcode);

		kfree_skb(nskb);

		goto bad;

		goto out2;

	}

	(void)skb_pull(skb, CAPIMSG_LEN(skb->data));

#ifdef _DEBUG_DATAFLOW

	printk(KERN_DEBUG "capi: DATA_B3_RESP %u len=%d => ldisc\n",

				datahandle, skb->len);

#endif

	ld->ops->receive_buf(mp->tty, skb->data, NULL, skb->len);

	ld->ops->receive_buf(tty, skb->data, NULL, skb->len);

	kfree_skb(skb);

	ret = 0;

out2:

	tty_ldisc_deref(ld);

	return 0;

bad:

	tty_ldisc_deref(ld);

	return -1;

out1:

	tty_kref_put(tty);

	return ret;

}



static void handle_minor_recv(struct capiminor *mp)
@@ -510,16 +524,22 @@ static void handle_minor_recv(struct capiminor *mp) 


static int handle_minor_send(struct capiminor *mp)

{

	struct tty_struct *tty;

	struct sk_buff *skb;

	u16 len;

	int count = 0;

	u16 errcode;

	u16 datahandle;



	if (mp->tty && mp->ttyoutstop) {

	tty = tty_port_tty_get(&mp->port);

	if (!tty)

		return 0;



	if (mp->ttyoutstop) {

#if defined(_DEBUG_DATAFLOW) || defined(_DEBUG_TTYFUNCS)

		printk(KERN_DEBUG "capi: send: tty stopped\n");

#endif

		tty_kref_put(tty);

		return 0;

	}
@@ -542,6 +562,7 @@ static int handle_minor_send(struct capiminor *mp) 
		if (capiminor_add_ack(mp, datahandle) < 0) {

			skb_pull(skb, CAPI_DATA_B3_REQ_LEN);

			skb_queue_head(&mp->outqueue, skb);

			tty_kref_put(tty);

			return count;

		}

		errcode = capi20_put_message(mp->ap, skb);
@@ -568,6 +589,7 @@ static int handle_minor_send(struct capiminor *mp) 
		mp->outbytes -= len;

		kfree_skb(skb);

	}

	tty_kref_put(tty);

	return count;

}
@@ -578,6 +600,7 @@ static void capi_recv_message(struct capi20_appl *ap, struct sk_buff *skb) 
{

	struct capidev *cdev = ap->private;

#ifdef CONFIG_ISDN_CAPI_MIDDLEWARE

	struct tty_struct *tty;

	struct capiminor *mp;

	u16 datahandle;

#endif /* CONFIG_ISDN_CAPI_MIDDLEWARE */
@@ -641,8 +664,11 @@ static void capi_recv_message(struct capi20_appl *ap, struct sk_buff *skb) 
#endif

		kfree_skb(skb);

		(void)capiminor_del_ack(mp, datahandle);

		if (mp->tty)

			tty_wakeup(mp->tty);

		tty = tty_port_tty_get(&mp->port);

		if (tty) {

			tty_wakeup(tty);

			tty_kref_put(tty);

		}

		(void)handle_minor_send(mp);



	} else {
@@ -1029,14 +1055,17 @@ static void capinc_tty_cleanup(struct tty_struct *tty) 
	capiminor_put(mp);

}



static int capinc_tty_open(struct tty_struct * tty, struct file * file)

static int capinc_tty_open(struct tty_struct *tty, struct file *filp)

{

	struct capiminor *mp = tty->driver_data;

	unsigned long flags;

	int err;



	err = tty_port_open(&mp->port, tty, filp);

	if (err)

		return err;



	spin_lock_irqsave(&workaround_lock, flags);

	if (atomic_read(&mp->ttyopencount) == 0)

		mp->tty = tty;

	atomic_inc(&mp->ttyopencount);

#ifdef _DEBUG_REFCOUNT

	printk(KERN_DEBUG "capinc_tty_open ocount=%d\n", atomic_read(&mp->ttyopencount));
@@ -1046,7 +1075,7 @@ static int capinc_tty_open(struct tty_struct * tty, struct file * file) 
	return 0;

}



static void capinc_tty_close(struct tty_struct * tty, struct file * file)

static void capinc_tty_close(struct tty_struct *tty, struct file *filp)

{

	struct capiminor *mp = tty->driver_data;
@@ -1054,17 +1083,15 @@ static void capinc_tty_close(struct tty_struct * tty, struct file * file) 
#ifdef _DEBUG_REFCOUNT

			printk(KERN_DEBUG "capinc_tty_close lastclose\n");

#endif

			mp->tty = NULL;

		}

#ifdef _DEBUG_REFCOUNT

		printk(KERN_DEBUG "capinc_tty_close ocount=%d\n", atomic_read(&mp->ttyopencount));

#endif

		if (mp->nccip == NULL)

			capiminor_free(mp);



#ifdef _DEBUG_REFCOUNT

	printk(KERN_DEBUG "capinc_tty_close\n");

#endif

	tty_port_close(&mp->port, tty, filp);

}



static int capinc_tty_write(struct tty_struct * tty,
@@ -1292,9 +1319,12 @@ static void capinc_tty_start(struct tty_struct *tty) 


static void capinc_tty_hangup(struct tty_struct *tty)

{

	struct capiminor *mp = tty->driver_data;



#ifdef _DEBUG_TTYFUNCS

	printk(KERN_DEBUG "capinc_tty_hangup\n");

#endif

	tty_port_hangup(&mp->port);

}



static int capinc_tty_break_ctl(struct tty_struct *tty, int state)