12874c5fdSThomas Gleixner /* SPDX-License-Identifier: GPL-2.0-or-later */ 21da177e4SLinus Torvalds #ifndef _PPP_CHANNEL_H_ 31da177e4SLinus Torvalds #define _PPP_CHANNEL_H_ 41da177e4SLinus Torvalds /* 51da177e4SLinus Torvalds * Definitions for the interface between the generic PPP code 61da177e4SLinus Torvalds * and a PPP channel. 71da177e4SLinus Torvalds * 81da177e4SLinus Torvalds * A PPP channel provides a way for the generic PPP code to send 91da177e4SLinus Torvalds * and receive packets over some sort of communications medium. 101da177e4SLinus Torvalds * Packets are stored in sk_buffs and have the 2-byte PPP protocol 111da177e4SLinus Torvalds * number at the start, but not the address and control bytes. 121da177e4SLinus Torvalds * 131da177e4SLinus Torvalds * Copyright 1999 Paul Mackerras. 141da177e4SLinus Torvalds * 151da177e4SLinus Torvalds * ==FILEVERSION 20000322== 161da177e4SLinus Torvalds */ 171da177e4SLinus Torvalds 181da177e4SLinus Torvalds #include <linux/list.h> 191da177e4SLinus Torvalds #include <linux/skbuff.h> 201da177e4SLinus Torvalds #include <linux/poll.h> 21273ec51dSCyrill Gorcunov #include <net/net_namespace.h> 221da177e4SLinus Torvalds 23*5f10376bSJakub Kicinski struct net_device_path; 24*5f10376bSJakub Kicinski struct net_device_path_ctx; 251da177e4SLinus Torvalds struct ppp_channel; 261da177e4SLinus Torvalds 271da177e4SLinus Torvalds struct ppp_channel_ops { 281da177e4SLinus Torvalds /* Send a packet (or multilink fragment) on this channel. 291da177e4SLinus Torvalds Returns 1 if it was accepted, 0 if not. */ 301da177e4SLinus Torvalds int (*start_xmit)(struct ppp_channel *, struct sk_buff *); 311da177e4SLinus Torvalds /* Handle an ioctl call that has come in via /dev/ppp. */ 321da177e4SLinus Torvalds int (*ioctl)(struct ppp_channel *, unsigned int, unsigned long); 33f6efc675SFelix Fietkau int (*fill_forward_path)(struct net_device_path_ctx *, 34f6efc675SFelix Fietkau struct net_device_path *, 35f6efc675SFelix Fietkau const struct ppp_channel *); 361da177e4SLinus Torvalds }; 371da177e4SLinus Torvalds 381da177e4SLinus Torvalds struct ppp_channel { 391da177e4SLinus Torvalds void *private; /* channel private data */ 40d7100da0Sstephen hemminger const struct ppp_channel_ops *ops; /* operations for this channel */ 411da177e4SLinus Torvalds int mtu; /* max transmit packet size */ 421da177e4SLinus Torvalds int hdrlen; /* amount of headroom channel needs */ 431da177e4SLinus Torvalds void *ppp; /* opaque to channel */ 441da177e4SLinus Torvalds int speed; /* transfer rate (bytes/second) */ 459c705260SGabriele Paoloni /* the following is not used at present */ 461da177e4SLinus Torvalds int latency; /* overhead time in milliseconds */ 471da177e4SLinus Torvalds }; 481da177e4SLinus Torvalds 491da177e4SLinus Torvalds #ifdef __KERNEL__ 501da177e4SLinus Torvalds /* Called by the channel when it can send some more data. */ 511da177e4SLinus Torvalds extern void ppp_output_wakeup(struct ppp_channel *); 521da177e4SLinus Torvalds 531da177e4SLinus Torvalds /* Called by the channel to process a received PPP packet. 541da177e4SLinus Torvalds The packet should have just the 2-byte PPP protocol header. */ 551da177e4SLinus Torvalds extern void ppp_input(struct ppp_channel *, struct sk_buff *); 561da177e4SLinus Torvalds 571da177e4SLinus Torvalds /* Called by the channel when an input error occurs, indicating 581da177e4SLinus Torvalds that we may have missed a packet. */ 591da177e4SLinus Torvalds extern void ppp_input_error(struct ppp_channel *, int code); 601da177e4SLinus Torvalds 61273ec51dSCyrill Gorcunov /* Attach a channel to a given PPP unit in specified net. */ 62273ec51dSCyrill Gorcunov extern int ppp_register_net_channel(struct net *, struct ppp_channel *); 63273ec51dSCyrill Gorcunov 641da177e4SLinus Torvalds /* Attach a channel to a given PPP unit. */ 651da177e4SLinus Torvalds extern int ppp_register_channel(struct ppp_channel *); 661da177e4SLinus Torvalds 671da177e4SLinus Torvalds /* Detach a channel from its PPP unit (e.g. on hangup). */ 681da177e4SLinus Torvalds extern void ppp_unregister_channel(struct ppp_channel *); 691da177e4SLinus Torvalds 701da177e4SLinus Torvalds /* Get the channel number for a channel */ 711da177e4SLinus Torvalds extern int ppp_channel_index(struct ppp_channel *); 721da177e4SLinus Torvalds 731da177e4SLinus Torvalds /* Get the unit number associated with a channel, or -1 if none */ 741da177e4SLinus Torvalds extern int ppp_unit_number(struct ppp_channel *); 751da177e4SLinus Torvalds 7663f96072SJames Chapman /* Get the device name associated with a channel, or NULL if none */ 7763f96072SJames Chapman extern char *ppp_dev_name(struct ppp_channel *); 7863f96072SJames Chapman 791da177e4SLinus Torvalds /* 801da177e4SLinus Torvalds * SMP locking notes: 811da177e4SLinus Torvalds * The channel code must ensure that when it calls ppp_unregister_channel, 821da177e4SLinus Torvalds * nothing is executing in any of the procedures above, for that 831da177e4SLinus Torvalds * channel. The generic layer will ensure that nothing is executing 841da177e4SLinus Torvalds * in the start_xmit and ioctl routines for the channel by the time 851da177e4SLinus Torvalds * that ppp_unregister_channel returns. 861da177e4SLinus Torvalds */ 871da177e4SLinus Torvalds 881da177e4SLinus Torvalds #endif /* __KERNEL__ */ 891da177e4SLinus Torvalds #endif 90