net/ppp/ppp_generic.c

12  * channel.
89  * interface unit or a ppp channel.  In both cases, file->private_data
101 	int		index;		/* interface unit / channel number */
102 	int		dead;		/* unit/channel has been shut down */
108 #define PF_TO_CHANNEL(pf)	PF_TO_X(pf, struct channel)
146 	int		nxchan;		/* next channel to send something on */
172  * Private data structure for each channel.
175 struct channel {
178 	struct ppp_channel *chan;	/* public channel data structure */
182 	struct net	*chan_net;	/* the net channel belongs to */
186 	struct channel __rcu *bridge;	/* "bridged" ppp channel */
191 	int		speed;		/* speed of the corresponding ppp channel*/
206  * The lock ordering is: channel.upl -> ppp.wlock -> ppp.rlock ->
207  * channel.downl.
235 	 * a channel and updating its file.refcnt field.
249  * the slowest channel relative to the others.  Strictly it should
268 static void ppp_channel_push(struct channel *pch);
270 			      struct channel *pch);
277 				struct channel *pch);
291 static struct channel *ppp_find_channel(struct ppp_net *pn, int unit);
292 static int ppp_connect_channel(struct channel *pch, int unit);
293 static int ppp_disconnect_channel(struct channel *pch);
294 static void ppp_destroy_channel(struct channel *pch);
391  * unattached, attached to a ppp unit, or attached to a ppp channel.
637 /* Bridge one PPP channel to another.
638  * When two channels are bridged, ppp_input on one channel is redirected to
642  * Once successfully bridged, each channel holds a reference on the other
645 static int ppp_bridge_channels(struct channel *pch, struct channel *pchb)
684 static int ppp_unbridge_channels(struct channel *pch)
686 	struct channel *pchb, *pchbb;
755 		struct channel *pch, *pchb;
810 		pr_err("PPP: not interface or channel??\n");
1055 	struct channel *chan;
1596 	struct channel *pch;
1604 	pch = list_first_entry(&ppp->channels, struct channel, clist);
1878 	struct channel *pch;
1893 		/* not doing multilink: send it down the first channel */
1895 		pch = list_entry(list, struct channel, clist);
1902 			/* channel got unregistered */
1942 	struct channel *pch;
2000 	/* skip to the channel after the one we last used
2011 	/* create a fragment for each channel */
2019 		pch = list_entry(list, struct channel, clist);
2025 		 * Skip this channel if it has a fragment pending already and
2035 		/* check the channel's mtu and whether it is still attached. */
2038 			/* can't use this channel, it's being deregistered */
2055 		*if the channel speed is not set divide
2058 		*of the channel we are going to transmit on
2081 		 *check if we are on the last channel or
2091 		 *Skip the channel in this case
2130 		/* try to send it down the channel */
2156 /* Try to send data out on a channel */
2157 static void __ppp_channel_push(struct channel *pch)
2173 		/* channel got deregistered */
2185 static void ppp_channel_push(struct channel *pch)
2214 ppp_do_recv(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
2264 /* Attempt to handle a frame via. a bridged channel, if one exists.
2265  * If the channel is bridged, the frame is consumed by the bridge.
2269 static bool ppp_channel_bridge_input(struct channel *pch, struct sk_buff *skb)
2271 	struct channel *pchb;
2280 		/* channel got unregistered */
2301 	struct channel *pch = chan->ppp;
2309 	/* If the channel is bridged, transmit via. bridge */
2325 		/* put it on the channel queue */
2344 	struct channel *pch = chan->ppp;
2367 ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
2373 		/* XXX do channel-level decompression here */
2609 ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
2612 	struct channel *ch;
2662 	 * last sequence number received on each channel.  Because of
2889 /* Create a new, unattached ppp channel. */
2895 /* Create a new, unattached ppp channel for specified net. */
2898 	struct channel *pch;
2901 	pch = kzalloc(sizeof(struct channel), GFP_KERNEL);
2930  * Return the index of a channel.
2934 	struct channel *pch = chan->ppp;
2942  * Return the PPP unit number to which a channel is connected.
2946 	struct channel *pch = chan->ppp;
2959  * Return the PPP device interface name of a channel.
2963 	struct channel *pch = chan->ppp;
2977  * Disconnect a channel from the generic layer.
2983 	struct channel *pch = chan->ppp;
2993 	 * the channel's start_xmit or ioctl routine before we proceed.
3017  * Callback from a channel when it can accept more to transmit.
3023 	struct channel *pch = chan->ppp;
3449  * Locate an existing ppp channel.
3456 static struct channel *
3459 	struct channel *pch;
3477  * Connect a PPP channel to a PPP interface unit.
3480 ppp_connect_channel(struct channel *pch, int unit)
3533  * Disconnect a channel from its ppp unit.
3536 ppp_disconnect_channel(struct channel *pch)
3560  * Free up the resources used by a ppp channel.
3562 static void ppp_destroy_channel(struct channel *pch)
3571 		pr_err("ppp: destroying undead channel %p !\n", pch);