2 * Generic PPP layer for Linux.
4 * Copyright 1999-2002 Paul Mackerras.
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
11 * The generic PPP layer handles the PPP network interfaces, the
12 * /dev/ppp device, packet and VJ compression, and multilink.
13 * It talks to PPP `channels' via the interface defined in
14 * include/linux/ppp_channel.h. Channels provide the basic means for
15 * sending and receiving PPP frames on some kind of communications
18 * Part of the code in this driver was inspired by the old async-only
19 * PPP driver, written by Michael Callahan and Al Longyear, and
20 * subsequently hacked by Paul Mackerras.
22 * ==FILEVERSION 20041108==
25 #include <linux/module.h>
26 #include <linux/kernel.h>
27 #include <linux/kmod.h>
28 #include <linux/init.h>
29 #include <linux/list.h>
30 #include <linux/netdevice.h>
31 #include <linux/poll.h>
32 #include <linux/ppp_defs.h>
33 #include <linux/filter.h>
34 #include <linux/if_ppp.h>
35 #include <linux/ppp_channel.h>
36 #include <linux/ppp-comp.h>
37 #include <linux/skbuff.h>
38 #include <linux/rtnetlink.h>
39 #include <linux/if_arp.h>
41 #include <linux/tcp.h>
42 #include <linux/spinlock.h>
43 #include <linux/smp_lock.h>
44 #include <linux/rwsem.h>
45 #include <linux/stddef.h>
46 #include <linux/device.h>
47 #include <linux/mutex.h>
48 #include <net/slhc_vj.h>
49 #include <asm/atomic.h>
51 #define PPP_VERSION "2.4.2"
54 * Network protocols we support.
56 #define NP_IP 0 /* Internet Protocol V4 */
57 #define NP_IPV6 1 /* Internet Protocol V6 */
58 #define NP_IPX 2 /* IPX protocol */
59 #define NP_AT 3 /* Appletalk protocol */
60 #define NP_MPLS_UC 4 /* MPLS unicast */
61 #define NP_MPLS_MC 5 /* MPLS multicast */
62 #define NUM_NP 6 /* Number of NPs. */
64 #define MPHDRLEN 6 /* multilink protocol header length */
65 #define MPHDRLEN_SSN 4 /* ditto with short sequence numbers */
66 #define MIN_FRAG_SIZE 64
69 * An instance of /dev/ppp can be associated with either a ppp
70 * interface unit or a ppp channel. In both cases, file->private_data
71 * points to one of these.
77 struct sk_buff_head xq
; /* pppd transmit queue */
78 struct sk_buff_head rq
; /* receive queue for pppd */
79 wait_queue_head_t rwait
; /* for poll on reading /dev/ppp */
80 atomic_t refcnt
; /* # refs (incl /dev/ppp attached) */
81 int hdrlen
; /* space to leave for headers */
82 int index
; /* interface unit / channel number */
83 int dead
; /* unit/channel has been shut down */
86 #define PF_TO_X(pf, X) container_of(pf, X, file)
88 #define PF_TO_PPP(pf) PF_TO_X(pf, struct ppp)
89 #define PF_TO_CHANNEL(pf) PF_TO_X(pf, struct channel)
92 * Data structure describing one ppp unit.
93 * A ppp unit corresponds to a ppp network interface device
94 * and represents a multilink bundle.
95 * It can have 0 or more ppp channels connected to it.
98 struct ppp_file file
; /* stuff for read/write/poll 0 */
99 struct file
*owner
; /* file that owns this unit 48 */
100 struct list_head channels
; /* list of attached channels 4c */
101 int n_channels
; /* how many channels are attached 54 */
102 spinlock_t rlock
; /* lock for receive side 58 */
103 spinlock_t wlock
; /* lock for transmit side 5c */
104 int mru
; /* max receive unit 60 */
105 unsigned int flags
; /* control bits 64 */
106 unsigned int xstate
; /* transmit state bits 68 */
107 unsigned int rstate
; /* receive state bits 6c */
108 int debug
; /* debug flags 70 */
109 struct slcompress
*vj
; /* state for VJ header compression */
110 enum NPmode npmode
[NUM_NP
]; /* what to do with each net proto 78 */
111 struct sk_buff
*xmit_pending
; /* a packet ready to go out 88 */
112 struct compressor
*xcomp
; /* transmit packet compressor 8c */
113 void *xc_state
; /* its internal state 90 */
114 struct compressor
*rcomp
; /* receive decompressor 94 */
115 void *rc_state
; /* its internal state 98 */
116 unsigned long last_xmit
; /* jiffies when last pkt sent 9c */
117 unsigned long last_recv
; /* jiffies when last pkt rcvd a0 */
118 struct net_device
*dev
; /* network interface device a4 */
119 #ifdef CONFIG_PPP_MULTILINK
120 int nxchan
; /* next channel to send something on */
121 u32 nxseq
; /* next sequence number to send */
122 int mrru
; /* MP: max reconst. receive unit */
123 u32 nextseq
; /* MP: seq no of next packet */
124 u32 minseq
; /* MP: min of most recent seqnos */
125 struct sk_buff_head mrq
; /* MP: receive reconstruction queue */
126 #endif /* CONFIG_PPP_MULTILINK */
127 struct net_device_stats stats
; /* statistics */
128 #ifdef CONFIG_PPP_FILTER
129 struct sock_filter
*pass_filter
; /* filter for packets to pass */
130 struct sock_filter
*active_filter
;/* filter for pkts to reset idle */
131 unsigned pass_len
, active_len
;
132 #endif /* CONFIG_PPP_FILTER */
136 * Bits in flags: SC_NO_TCP_CCID, SC_CCP_OPEN, SC_CCP_UP, SC_LOOP_TRAFFIC,
137 * SC_MULTILINK, SC_MP_SHORTSEQ, SC_MP_XSHORTSEQ, SC_COMP_TCP, SC_REJ_COMP_TCP,
139 * Bits in rstate: SC_DECOMP_RUN, SC_DC_ERROR, SC_DC_FERROR.
140 * Bits in xstate: SC_COMP_RUN
142 #define SC_FLAG_BITS (SC_NO_TCP_CCID|SC_CCP_OPEN|SC_CCP_UP|SC_LOOP_TRAFFIC \
143 |SC_MULTILINK|SC_MP_SHORTSEQ|SC_MP_XSHORTSEQ \
144 |SC_COMP_TCP|SC_REJ_COMP_TCP|SC_MUST_COMP)
147 * Private data structure for each channel.
148 * This includes the data structure used for multilink.
151 struct ppp_file file
; /* stuff for read/write/poll */
152 struct list_head list
; /* link in all/new_channels list */
153 struct ppp_channel
*chan
; /* public channel data structure */
154 struct rw_semaphore chan_sem
; /* protects `chan' during chan ioctl */
155 spinlock_t downl
; /* protects `chan', file.xq dequeue */
156 struct ppp
*ppp
; /* ppp unit we're connected to */
157 struct list_head clist
; /* link in list of channels per unit */
158 rwlock_t upl
; /* protects `ppp' */
159 #ifdef CONFIG_PPP_MULTILINK
160 u8 avail
; /* flag used in multilink stuff */
161 u8 had_frag
; /* >= 1 fragments have been sent */
162 u32 lastseq
; /* MP: last sequence # received */
163 #endif /* CONFIG_PPP_MULTILINK */
167 * SMP locking issues:
168 * Both the ppp.rlock and ppp.wlock locks protect the ppp.channels
169 * list and the ppp.n_channels field, you need to take both locks
170 * before you modify them.
171 * The lock ordering is: channel.upl -> ppp.wlock -> ppp.rlock ->
176 * A cardmap represents a mapping from unsigned integers to pointers,
177 * and provides a fast "find lowest unused number" operation.
178 * It uses a broad (32-way) tree with a bitmap at each level.
179 * It is designed to be space-efficient for small numbers of entries
180 * and time-efficient for large numbers of entries.
182 #define CARDMAP_ORDER 5
183 #define CARDMAP_WIDTH (1U << CARDMAP_ORDER)
184 #define CARDMAP_MASK (CARDMAP_WIDTH - 1)
189 struct cardmap
*parent
;
190 void *ptr
[CARDMAP_WIDTH
];
192 static void *cardmap_get(struct cardmap
*map
, unsigned int nr
);
193 static int cardmap_set(struct cardmap
**map
, unsigned int nr
, void *ptr
);
194 static unsigned int cardmap_find_first_free(struct cardmap
*map
);
195 static void cardmap_destroy(struct cardmap
**map
);
198 * all_ppp_mutex protects the all_ppp_units mapping.
199 * It also ensures that finding a ppp unit in the all_ppp_units map
200 * and updating its file.refcnt field is atomic.
202 static DEFINE_MUTEX(all_ppp_mutex
);
203 static struct cardmap
*all_ppp_units
;
204 static atomic_t ppp_unit_count
= ATOMIC_INIT(0);
207 * all_channels_lock protects all_channels and last_channel_index,
208 * and the atomicity of find a channel and updating its file.refcnt
211 static DEFINE_SPINLOCK(all_channels_lock
);
212 static LIST_HEAD(all_channels
);
213 static LIST_HEAD(new_channels
);
214 static int last_channel_index
;
215 static atomic_t channel_count
= ATOMIC_INIT(0);
217 /* Get the PPP protocol number from a skb */
218 #define PPP_PROTO(skb) (((skb)->data[0] << 8) + (skb)->data[1])
220 /* We limit the length of ppp->file.rq to this (arbitrary) value */
221 #define PPP_MAX_RQLEN 32
224 * Maximum number of multilink fragments queued up.
225 * This has to be large enough to cope with the maximum latency of
226 * the slowest channel relative to the others. Strictly it should
227 * depend on the number of channels and their characteristics.
229 #define PPP_MP_MAX_QLEN 128
231 /* Multilink header bits. */
232 #define B 0x80 /* this fragment begins a packet */
233 #define E 0x40 /* this fragment ends a packet */
235 /* Compare multilink sequence numbers (assumed to be 32 bits wide) */
236 #define seq_before(a, b) ((s32)((a) - (b)) < 0)
237 #define seq_after(a, b) ((s32)((a) - (b)) > 0)
240 static int ppp_unattached_ioctl(struct ppp_file
*pf
, struct file
*file
,
241 unsigned int cmd
, unsigned long arg
);
242 static void ppp_xmit_process(struct ppp
*ppp
);
243 static void ppp_send_frame(struct ppp
*ppp
, struct sk_buff
*skb
);
244 static void ppp_push(struct ppp
*ppp
);
245 static void ppp_channel_push(struct channel
*pch
);
246 static void ppp_receive_frame(struct ppp
*ppp
, struct sk_buff
*skb
,
247 struct channel
*pch
);
248 static void ppp_receive_error(struct ppp
*ppp
);
249 static void ppp_receive_nonmp_frame(struct ppp
*ppp
, struct sk_buff
*skb
);
250 static struct sk_buff
*ppp_decompress_frame(struct ppp
*ppp
,
251 struct sk_buff
*skb
);
252 #ifdef CONFIG_PPP_MULTILINK
253 static void ppp_receive_mp_frame(struct ppp
*ppp
, struct sk_buff
*skb
,
254 struct channel
*pch
);
255 static void ppp_mp_insert(struct ppp
*ppp
, struct sk_buff
*skb
);
256 static struct sk_buff
*ppp_mp_reconstruct(struct ppp
*ppp
);
257 static int ppp_mp_explode(struct ppp
*ppp
, struct sk_buff
*skb
);
258 #endif /* CONFIG_PPP_MULTILINK */
259 static int ppp_set_compress(struct ppp
*ppp
, unsigned long arg
);
260 static void ppp_ccp_peek(struct ppp
*ppp
, struct sk_buff
*skb
, int inbound
);
261 static void ppp_ccp_closed(struct ppp
*ppp
);
262 static struct compressor
*find_compressor(int type
);
263 static void ppp_get_stats(struct ppp
*ppp
, struct ppp_stats
*st
);
264 static struct ppp
*ppp_create_interface(int unit
, int *retp
);
265 static void init_ppp_file(struct ppp_file
*pf
, int kind
);
266 static void ppp_shutdown_interface(struct ppp
*ppp
);
267 static void ppp_destroy_interface(struct ppp
*ppp
);
268 static struct ppp
*ppp_find_unit(int unit
);
269 static struct channel
*ppp_find_channel(int unit
);
270 static int ppp_connect_channel(struct channel
*pch
, int unit
);
271 static int ppp_disconnect_channel(struct channel
*pch
);
272 static void ppp_destroy_channel(struct channel
*pch
);
274 static struct class *ppp_class
;
276 /* Translates a PPP protocol number to a NP index (NP == network protocol) */
277 static inline int proto_to_npindex(int proto
)
296 /* Translates an NP index into a PPP protocol number */
297 static const int npindex_to_proto
[NUM_NP
] = {
306 /* Translates an ethertype into an NP index */
307 static inline int ethertype_to_npindex(int ethertype
)
327 /* Translates an NP index into an ethertype */
328 static const int npindex_to_ethertype
[NUM_NP
] = {
340 #define ppp_xmit_lock(ppp) spin_lock_bh(&(ppp)->wlock)
341 #define ppp_xmit_unlock(ppp) spin_unlock_bh(&(ppp)->wlock)
342 #define ppp_recv_lock(ppp) spin_lock_bh(&(ppp)->rlock)
343 #define ppp_recv_unlock(ppp) spin_unlock_bh(&(ppp)->rlock)
344 #define ppp_lock(ppp) do { ppp_xmit_lock(ppp); \
345 ppp_recv_lock(ppp); } while (0)
346 #define ppp_unlock(ppp) do { ppp_recv_unlock(ppp); \
347 ppp_xmit_unlock(ppp); } while (0)
350 * /dev/ppp device routines.
351 * The /dev/ppp device is used by pppd to control the ppp unit.
352 * It supports the read, write, ioctl and poll functions.
353 * Open instances of /dev/ppp can be in one of three states:
354 * unattached, attached to a ppp unit, or attached to a ppp channel.
356 static int ppp_open(struct inode
*inode
, struct file
*file
)
359 * This could (should?) be enforced by the permissions on /dev/ppp.
361 if (!capable(CAP_NET_ADMIN
))
366 static int ppp_release(struct inode
*inode
, struct file
*file
)
368 struct ppp_file
*pf
= file
->private_data
;
372 file
->private_data
= NULL
;
373 if (pf
->kind
== INTERFACE
) {
375 if (file
== ppp
->owner
)
376 ppp_shutdown_interface(ppp
);
378 if (atomic_dec_and_test(&pf
->refcnt
)) {
381 ppp_destroy_interface(PF_TO_PPP(pf
));
384 ppp_destroy_channel(PF_TO_CHANNEL(pf
));
392 static ssize_t
ppp_read(struct file
*file
, char __user
*buf
,
393 size_t count
, loff_t
*ppos
)
395 struct ppp_file
*pf
= file
->private_data
;
396 DECLARE_WAITQUEUE(wait
, current
);
398 struct sk_buff
*skb
= NULL
;
404 add_wait_queue(&pf
->rwait
, &wait
);
406 set_current_state(TASK_INTERRUPTIBLE
);
407 skb
= skb_dequeue(&pf
->rq
);
413 if (pf
->kind
== INTERFACE
) {
415 * Return 0 (EOF) on an interface that has no
416 * channels connected, unless it is looping
417 * network traffic (demand mode).
419 struct ppp
*ppp
= PF_TO_PPP(pf
);
420 if (ppp
->n_channels
== 0
421 && (ppp
->flags
& SC_LOOP_TRAFFIC
) == 0)
425 if (file
->f_flags
& O_NONBLOCK
)
428 if (signal_pending(current
))
432 set_current_state(TASK_RUNNING
);
433 remove_wait_queue(&pf
->rwait
, &wait
);
439 if (skb
->len
> count
)
442 if (copy_to_user(buf
, skb
->data
, skb
->len
))
452 static ssize_t
ppp_write(struct file
*file
, const char __user
*buf
,
453 size_t count
, loff_t
*ppos
)
455 struct ppp_file
*pf
= file
->private_data
;
462 skb
= alloc_skb(count
+ pf
->hdrlen
, GFP_KERNEL
);
465 skb_reserve(skb
, pf
->hdrlen
);
467 if (copy_from_user(skb_put(skb
, count
), buf
, count
)) {
472 skb_queue_tail(&pf
->xq
, skb
);
476 ppp_xmit_process(PF_TO_PPP(pf
));
479 ppp_channel_push(PF_TO_CHANNEL(pf
));
489 /* No kernel lock - fine */
490 static unsigned int ppp_poll(struct file
*file
, poll_table
*wait
)
492 struct ppp_file
*pf
= file
->private_data
;
497 poll_wait(file
, &pf
->rwait
, wait
);
498 mask
= POLLOUT
| POLLWRNORM
;
499 if (skb_peek(&pf
->rq
) != 0)
500 mask
|= POLLIN
| POLLRDNORM
;
503 else if (pf
->kind
== INTERFACE
) {
504 /* see comment in ppp_read */
505 struct ppp
*ppp
= PF_TO_PPP(pf
);
506 if (ppp
->n_channels
== 0
507 && (ppp
->flags
& SC_LOOP_TRAFFIC
) == 0)
508 mask
|= POLLIN
| POLLRDNORM
;
514 #ifdef CONFIG_PPP_FILTER
515 static int get_filter(void __user
*arg
, struct sock_filter
**p
)
517 struct sock_fprog uprog
;
518 struct sock_filter
*code
= NULL
;
521 if (copy_from_user(&uprog
, arg
, sizeof(uprog
)))
529 len
= uprog
.len
* sizeof(struct sock_filter
);
530 code
= kmalloc(len
, GFP_KERNEL
);
534 if (copy_from_user(code
, uprog
.filter
, len
)) {
539 err
= sk_chk_filter(code
, uprog
.len
);
548 #endif /* CONFIG_PPP_FILTER */
550 static int ppp_ioctl(struct inode
*inode
, struct file
*file
,
551 unsigned int cmd
, unsigned long arg
)
553 struct ppp_file
*pf
= file
->private_data
;
555 int err
= -EFAULT
, val
, val2
, i
;
556 struct ppp_idle idle
;
559 struct slcompress
*vj
;
560 void __user
*argp
= (void __user
*)arg
;
561 int __user
*p
= argp
;
564 return ppp_unattached_ioctl(pf
, file
, cmd
, arg
);
566 if (cmd
== PPPIOCDETACH
) {
568 * We have to be careful here... if the file descriptor
569 * has been dup'd, we could have another process in the
570 * middle of a poll using the same file *, so we had
571 * better not free the interface data structures -
572 * instead we fail the ioctl. Even in this case, we
573 * shut down the interface if we are the owner of it.
574 * Actually, we should get rid of PPPIOCDETACH, userland
575 * (i.e. pppd) could achieve the same effect by closing
576 * this fd and reopening /dev/ppp.
579 if (pf
->kind
== INTERFACE
) {
581 if (file
== ppp
->owner
)
582 ppp_shutdown_interface(ppp
);
584 if (atomic_read(&file
->f_count
) <= 2) {
585 ppp_release(inode
, file
);
588 printk(KERN_DEBUG
"PPPIOCDETACH file->f_count=%d\n",
589 atomic_read(&file
->f_count
));
593 if (pf
->kind
== CHANNEL
) {
594 struct channel
*pch
= PF_TO_CHANNEL(pf
);
595 struct ppp_channel
*chan
;
599 if (get_user(unit
, p
))
601 err
= ppp_connect_channel(pch
, unit
);
605 err
= ppp_disconnect_channel(pch
);
609 down_read(&pch
->chan_sem
);
612 if (chan
&& chan
->ops
->ioctl
)
613 err
= chan
->ops
->ioctl(chan
, cmd
, arg
);
614 up_read(&pch
->chan_sem
);
619 if (pf
->kind
!= INTERFACE
) {
621 printk(KERN_ERR
"PPP: not interface or channel??\n");
628 if (get_user(val
, p
))
635 if (get_user(val
, p
))
638 cflags
= ppp
->flags
& ~val
;
639 ppp
->flags
= val
& SC_FLAG_BITS
;
641 if (cflags
& SC_CCP_OPEN
)
647 val
= ppp
->flags
| ppp
->xstate
| ppp
->rstate
;
648 if (put_user(val
, p
))
653 case PPPIOCSCOMPRESS
:
654 err
= ppp_set_compress(ppp
, arg
);
658 if (put_user(ppp
->file
.index
, p
))
664 if (get_user(val
, p
))
671 if (put_user(ppp
->debug
, p
))
677 idle
.xmit_idle
= (jiffies
- ppp
->last_xmit
) / HZ
;
678 idle
.recv_idle
= (jiffies
- ppp
->last_recv
) / HZ
;
679 if (copy_to_user(argp
, &idle
, sizeof(idle
)))
685 if (get_user(val
, p
))
688 if ((val
>> 16) != 0) {
692 vj
= slhc_init(val2
+1, val
+1);
694 printk(KERN_ERR
"PPP: no memory (VJ compressor)\n");
708 if (copy_from_user(&npi
, argp
, sizeof(npi
)))
710 err
= proto_to_npindex(npi
.protocol
);
714 if (cmd
== PPPIOCGNPMODE
) {
716 npi
.mode
= ppp
->npmode
[i
];
717 if (copy_to_user(argp
, &npi
, sizeof(npi
)))
720 ppp
->npmode
[i
] = npi
.mode
;
721 /* we may be able to transmit more packets now (??) */
722 netif_wake_queue(ppp
->dev
);
727 #ifdef CONFIG_PPP_FILTER
730 struct sock_filter
*code
;
731 err
= get_filter(argp
, &code
);
734 kfree(ppp
->pass_filter
);
735 ppp
->pass_filter
= code
;
744 struct sock_filter
*code
;
745 err
= get_filter(argp
, &code
);
748 kfree(ppp
->active_filter
);
749 ppp
->active_filter
= code
;
750 ppp
->active_len
= err
;
756 #endif /* CONFIG_PPP_FILTER */
758 #ifdef CONFIG_PPP_MULTILINK
760 if (get_user(val
, p
))
764 ppp_recv_unlock(ppp
);
767 #endif /* CONFIG_PPP_MULTILINK */
776 static int ppp_unattached_ioctl(struct ppp_file
*pf
, struct file
*file
,
777 unsigned int cmd
, unsigned long arg
)
779 int unit
, err
= -EFAULT
;
781 struct channel
*chan
;
782 int __user
*p
= (int __user
*)arg
;
786 /* Create a new ppp unit */
787 if (get_user(unit
, p
))
789 ppp
= ppp_create_interface(unit
, &err
);
792 file
->private_data
= &ppp
->file
;
795 if (put_user(ppp
->file
.index
, p
))
801 /* Attach to an existing ppp unit */
802 if (get_user(unit
, p
))
804 mutex_lock(&all_ppp_mutex
);
806 ppp
= ppp_find_unit(unit
);
808 atomic_inc(&ppp
->file
.refcnt
);
809 file
->private_data
= &ppp
->file
;
812 mutex_unlock(&all_ppp_mutex
);
816 if (get_user(unit
, p
))
818 spin_lock_bh(&all_channels_lock
);
820 chan
= ppp_find_channel(unit
);
822 atomic_inc(&chan
->file
.refcnt
);
823 file
->private_data
= &chan
->file
;
826 spin_unlock_bh(&all_channels_lock
);
835 static const struct file_operations ppp_device_fops
= {
836 .owner
= THIS_MODULE
,
842 .release
= ppp_release
845 #define PPP_MAJOR 108
847 /* Called at boot time if ppp is compiled into the kernel,
848 or at module load time (from init_module) if compiled as a module. */
849 static int __init
ppp_init(void)
853 printk(KERN_INFO
"PPP generic driver version " PPP_VERSION
"\n");
854 err
= register_chrdev(PPP_MAJOR
, "ppp", &ppp_device_fops
);
856 ppp_class
= class_create(THIS_MODULE
, "ppp");
857 if (IS_ERR(ppp_class
)) {
858 err
= PTR_ERR(ppp_class
);
861 device_create(ppp_class
, NULL
, MKDEV(PPP_MAJOR
, 0), "ppp");
866 printk(KERN_ERR
"failed to register PPP device (%d)\n", err
);
870 unregister_chrdev(PPP_MAJOR
, "ppp");
875 * Network interface unit routines.
878 ppp_start_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
880 struct ppp
*ppp
= (struct ppp
*) dev
->priv
;
884 npi
= ethertype_to_npindex(ntohs(skb
->protocol
));
888 /* Drop, accept or reject the packet */
889 switch (ppp
->npmode
[npi
]) {
893 /* it would be nice to have a way to tell the network
894 system to queue this one up for later. */
901 /* Put the 2-byte PPP protocol number on the front,
902 making sure there is room for the address and control fields. */
903 if (skb_headroom(skb
) < PPP_HDRLEN
) {
906 ns
= alloc_skb(skb
->len
+ dev
->hard_header_len
, GFP_ATOMIC
);
909 skb_reserve(ns
, dev
->hard_header_len
);
910 skb_copy_bits(skb
, 0, skb_put(ns
, skb
->len
), skb
->len
);
914 pp
= skb_push(skb
, 2);
915 proto
= npindex_to_proto
[npi
];
919 netif_stop_queue(dev
);
920 skb_queue_tail(&ppp
->file
.xq
, skb
);
921 ppp_xmit_process(ppp
);
926 ++ppp
->stats
.tx_dropped
;
930 static struct net_device_stats
*
931 ppp_net_stats(struct net_device
*dev
)
933 struct ppp
*ppp
= (struct ppp
*) dev
->priv
;
939 ppp_net_ioctl(struct net_device
*dev
, struct ifreq
*ifr
, int cmd
)
941 struct ppp
*ppp
= dev
->priv
;
943 void __user
*addr
= (void __user
*) ifr
->ifr_ifru
.ifru_data
;
944 struct ppp_stats stats
;
945 struct ppp_comp_stats cstats
;
950 ppp_get_stats(ppp
, &stats
);
951 if (copy_to_user(addr
, &stats
, sizeof(stats
)))
957 memset(&cstats
, 0, sizeof(cstats
));
958 if (ppp
->xc_state
!= 0)
959 ppp
->xcomp
->comp_stat(ppp
->xc_state
, &cstats
.c
);
960 if (ppp
->rc_state
!= 0)
961 ppp
->rcomp
->decomp_stat(ppp
->rc_state
, &cstats
.d
);
962 if (copy_to_user(addr
, &cstats
, sizeof(cstats
)))
969 if (copy_to_user(addr
, vers
, strlen(vers
) + 1))
981 static void ppp_setup(struct net_device
*dev
)
983 dev
->hard_header_len
= PPP_HDRLEN
;
986 dev
->tx_queue_len
= 3;
987 dev
->type
= ARPHRD_PPP
;
988 dev
->flags
= IFF_POINTOPOINT
| IFF_NOARP
| IFF_MULTICAST
;
992 * Transmit-side routines.
996 * Called to do any work queued up on the transmit side
997 * that can now be done.
1000 ppp_xmit_process(struct ppp
*ppp
)
1002 struct sk_buff
*skb
;
1005 if (ppp
->dev
!= 0) {
1007 while (ppp
->xmit_pending
== 0
1008 && (skb
= skb_dequeue(&ppp
->file
.xq
)) != 0)
1009 ppp_send_frame(ppp
, skb
);
1010 /* If there's no work left to do, tell the core net
1011 code that we can accept some more. */
1012 if (ppp
->xmit_pending
== 0 && skb_peek(&ppp
->file
.xq
) == 0)
1013 netif_wake_queue(ppp
->dev
);
1015 ppp_xmit_unlock(ppp
);
1018 static inline struct sk_buff
*
1019 pad_compress_skb(struct ppp
*ppp
, struct sk_buff
*skb
)
1021 struct sk_buff
*new_skb
;
1023 int new_skb_size
= ppp
->dev
->mtu
+
1024 ppp
->xcomp
->comp_extra
+ ppp
->dev
->hard_header_len
;
1025 int compressor_skb_size
= ppp
->dev
->mtu
+
1026 ppp
->xcomp
->comp_extra
+ PPP_HDRLEN
;
1027 new_skb
= alloc_skb(new_skb_size
, GFP_ATOMIC
);
1029 if (net_ratelimit())
1030 printk(KERN_ERR
"PPP: no memory (comp pkt)\n");
1033 if (ppp
->dev
->hard_header_len
> PPP_HDRLEN
)
1034 skb_reserve(new_skb
,
1035 ppp
->dev
->hard_header_len
- PPP_HDRLEN
);
1037 /* compressor still expects A/C bytes in hdr */
1038 len
= ppp
->xcomp
->compress(ppp
->xc_state
, skb
->data
- 2,
1039 new_skb
->data
, skb
->len
+ 2,
1040 compressor_skb_size
);
1041 if (len
> 0 && (ppp
->flags
& SC_CCP_UP
)) {
1045 skb_pull(skb
, 2); /* pull off A/C bytes */
1046 } else if (len
== 0) {
1047 /* didn't compress, or CCP not up yet */
1053 * MPPE requires that we do not send unencrypted
1054 * frames. The compressor will return -1 if we
1055 * should drop the frame. We cannot simply test
1056 * the compress_proto because MPPE and MPPC share
1059 if (net_ratelimit())
1060 printk(KERN_ERR
"ppp: compressor dropped pkt\n");
1069 * Compress and send a frame.
1070 * The caller should have locked the xmit path,
1071 * and xmit_pending should be 0.
1074 ppp_send_frame(struct ppp
*ppp
, struct sk_buff
*skb
)
1076 int proto
= PPP_PROTO(skb
);
1077 struct sk_buff
*new_skb
;
1081 if (proto
< 0x8000) {
1082 #ifdef CONFIG_PPP_FILTER
1083 /* check if we should pass this packet */
1084 /* the filter instructions are constructed assuming
1085 a four-byte PPP header on each packet */
1086 *skb_push(skb
, 2) = 1;
1087 if (ppp
->pass_filter
1088 && sk_run_filter(skb
, ppp
->pass_filter
,
1089 ppp
->pass_len
) == 0) {
1091 printk(KERN_DEBUG
"PPP: outbound frame not passed\n");
1095 /* if this packet passes the active filter, record the time */
1096 if (!(ppp
->active_filter
1097 && sk_run_filter(skb
, ppp
->active_filter
,
1098 ppp
->active_len
) == 0))
1099 ppp
->last_xmit
= jiffies
;
1102 /* for data packets, record the time */
1103 ppp
->last_xmit
= jiffies
;
1104 #endif /* CONFIG_PPP_FILTER */
1107 ++ppp
->stats
.tx_packets
;
1108 ppp
->stats
.tx_bytes
+= skb
->len
- 2;
1112 if (ppp
->vj
== 0 || (ppp
->flags
& SC_COMP_TCP
) == 0)
1114 /* try to do VJ TCP header compression */
1115 new_skb
= alloc_skb(skb
->len
+ ppp
->dev
->hard_header_len
- 2,
1118 printk(KERN_ERR
"PPP: no memory (VJ comp pkt)\n");
1121 skb_reserve(new_skb
, ppp
->dev
->hard_header_len
- 2);
1123 len
= slhc_compress(ppp
->vj
, cp
, skb
->len
- 2,
1124 new_skb
->data
+ 2, &cp
,
1125 !(ppp
->flags
& SC_NO_TCP_CCID
));
1126 if (cp
== skb
->data
+ 2) {
1127 /* didn't compress */
1130 if (cp
[0] & SL_TYPE_COMPRESSED_TCP
) {
1131 proto
= PPP_VJC_COMP
;
1132 cp
[0] &= ~SL_TYPE_COMPRESSED_TCP
;
1134 proto
= PPP_VJC_UNCOMP
;
1135 cp
[0] = skb
->data
[2];
1139 cp
= skb_put(skb
, len
+ 2);
1146 /* peek at outbound CCP frames */
1147 ppp_ccp_peek(ppp
, skb
, 0);
1151 /* try to do packet compression */
1152 if ((ppp
->xstate
& SC_COMP_RUN
) && ppp
->xc_state
!= 0
1153 && proto
!= PPP_LCP
&& proto
!= PPP_CCP
) {
1154 if (!(ppp
->flags
& SC_CCP_UP
) && (ppp
->flags
& SC_MUST_COMP
)) {
1155 if (net_ratelimit())
1156 printk(KERN_ERR
"ppp: compression required but down - pkt dropped.\n");
1159 skb
= pad_compress_skb(ppp
, skb
);
1165 * If we are waiting for traffic (demand dialling),
1166 * queue it up for pppd to receive.
1168 if (ppp
->flags
& SC_LOOP_TRAFFIC
) {
1169 if (ppp
->file
.rq
.qlen
> PPP_MAX_RQLEN
)
1171 skb_queue_tail(&ppp
->file
.rq
, skb
);
1172 wake_up_interruptible(&ppp
->file
.rwait
);
1176 ppp
->xmit_pending
= skb
;
1183 ++ppp
->stats
.tx_errors
;
1187 * Try to send the frame in xmit_pending.
1188 * The caller should have the xmit path locked.
1191 ppp_push(struct ppp
*ppp
)
1193 struct list_head
*list
;
1194 struct channel
*pch
;
1195 struct sk_buff
*skb
= ppp
->xmit_pending
;
1200 list
= &ppp
->channels
;
1201 if (list_empty(list
)) {
1202 /* nowhere to send the packet, just drop it */
1203 ppp
->xmit_pending
= NULL
;
1208 if ((ppp
->flags
& SC_MULTILINK
) == 0) {
1209 /* not doing multilink: send it down the first channel */
1211 pch
= list_entry(list
, struct channel
, clist
);
1213 spin_lock_bh(&pch
->downl
);
1215 if (pch
->chan
->ops
->start_xmit(pch
->chan
, skb
))
1216 ppp
->xmit_pending
= NULL
;
1218 /* channel got unregistered */
1220 ppp
->xmit_pending
= NULL
;
1222 spin_unlock_bh(&pch
->downl
);
1226 #ifdef CONFIG_PPP_MULTILINK
1227 /* Multilink: fragment the packet over as many links
1228 as can take the packet at the moment. */
1229 if (!ppp_mp_explode(ppp
, skb
))
1231 #endif /* CONFIG_PPP_MULTILINK */
1233 ppp
->xmit_pending
= NULL
;
1237 #ifdef CONFIG_PPP_MULTILINK
1239 * Divide a packet to be transmitted into fragments and
1240 * send them out the individual links.
1242 static int ppp_mp_explode(struct ppp
*ppp
, struct sk_buff
*skb
)
1245 int i
, bits
, hdrlen
, mtu
;
1249 unsigned char *p
, *q
;
1250 struct list_head
*list
;
1251 struct channel
*pch
;
1252 struct sk_buff
*frag
;
1253 struct ppp_channel
*chan
;
1255 nfree
= 0; /* # channels which have no packet already queued */
1256 navail
= 0; /* total # of usable channels (not deregistered) */
1257 hdrlen
= (ppp
->flags
& SC_MP_XSHORTSEQ
)? MPHDRLEN_SSN
: MPHDRLEN
;
1259 list_for_each_entry(pch
, &ppp
->channels
, clist
) {
1260 navail
+= pch
->avail
= (pch
->chan
!= NULL
);
1262 if (skb_queue_empty(&pch
->file
.xq
) ||
1267 if (!pch
->had_frag
&& i
< ppp
->nxchan
)
1274 * Don't start sending this packet unless at least half of
1275 * the channels are free. This gives much better TCP
1276 * performance if we have a lot of channels.
1278 if (nfree
== 0 || nfree
< navail
/ 2)
1279 return 0; /* can't take now, leave it in xmit_pending */
1281 /* Do protocol field compression (XXX this should be optional) */
1290 * Decide on fragment size.
1291 * We create a fragment for each free channel regardless of
1292 * how small they are (i.e. even 0 length) in order to minimize
1293 * the time that it will take to detect when a channel drops
1298 fragsize
= DIV_ROUND_UP(fragsize
, nfree
);
1299 /* nbigger channels get fragsize bytes, the rest get fragsize-1,
1300 except if nbigger==0, then they all get fragsize. */
1301 nbigger
= len
% nfree
;
1303 /* skip to the channel after the one we last used
1304 and start at that one */
1305 list
= &ppp
->channels
;
1306 for (i
= 0; i
< ppp
->nxchan
; ++i
) {
1308 if (list
== &ppp
->channels
) {
1314 /* create a fragment for each channel */
1316 while (nfree
> 0 || len
> 0) {
1318 if (list
== &ppp
->channels
) {
1322 pch
= list_entry(list
, struct channel
, clist
);
1328 * Skip this channel if it has a fragment pending already and
1329 * we haven't given a fragment to all of the free channels.
1331 if (pch
->avail
== 1) {
1339 /* check the channel's mtu and whether it is still attached. */
1340 spin_lock_bh(&pch
->downl
);
1341 if (pch
->chan
== NULL
) {
1342 /* can't use this channel, it's being deregistered */
1343 spin_unlock_bh(&pch
->downl
);
1351 * Create a fragment for this channel of
1352 * min(max(mtu+2-hdrlen, 4), fragsize, len) bytes.
1353 * If mtu+2-hdrlen < 4, that is a ridiculously small
1354 * MTU, so we use mtu = 2 + hdrlen.
1359 mtu
= pch
->chan
->mtu
+ 2 - hdrlen
;
1364 if (flen
== len
&& nfree
== 0)
1366 frag
= alloc_skb(flen
+ hdrlen
+ (flen
== 0), GFP_ATOMIC
);
1369 q
= skb_put(frag
, flen
+ hdrlen
);
1371 /* make the MP header */
1374 if (ppp
->flags
& SC_MP_XSHORTSEQ
) {
1375 q
[2] = bits
+ ((ppp
->nxseq
>> 8) & 0xf);
1379 q
[3] = ppp
->nxseq
>> 16;
1380 q
[4] = ppp
->nxseq
>> 8;
1386 * Unfortunately there is a bug in older versions of
1387 * the Linux PPP multilink reconstruction code where it
1388 * drops 0-length fragments. Therefore we make sure the
1389 * fragment has at least one byte of data. Any bytes
1390 * we add in this situation will end up as padding on the
1391 * end of the reconstructed packet.
1394 *skb_put(frag
, 1) = 0;
1396 memcpy(q
+ hdrlen
, p
, flen
);
1398 /* try to send it down the channel */
1400 if (!skb_queue_empty(&pch
->file
.xq
) ||
1401 !chan
->ops
->start_xmit(chan
, frag
))
1402 skb_queue_tail(&pch
->file
.xq
, frag
);
1408 spin_unlock_bh(&pch
->downl
);
1410 if (--nbigger
== 0 && fragsize
> 0)
1418 spin_unlock_bh(&pch
->downl
);
1420 printk(KERN_ERR
"PPP: no memory (fragment)\n");
1421 ++ppp
->stats
.tx_errors
;
1423 return 1; /* abandon the frame */
1425 #endif /* CONFIG_PPP_MULTILINK */
1428 * Try to send data out on a channel.
1431 ppp_channel_push(struct channel
*pch
)
1433 struct sk_buff
*skb
;
1436 spin_lock_bh(&pch
->downl
);
1437 if (pch
->chan
!= 0) {
1438 while (!skb_queue_empty(&pch
->file
.xq
)) {
1439 skb
= skb_dequeue(&pch
->file
.xq
);
1440 if (!pch
->chan
->ops
->start_xmit(pch
->chan
, skb
)) {
1441 /* put the packet back and try again later */
1442 skb_queue_head(&pch
->file
.xq
, skb
);
1447 /* channel got deregistered */
1448 skb_queue_purge(&pch
->file
.xq
);
1450 spin_unlock_bh(&pch
->downl
);
1451 /* see if there is anything from the attached unit to be sent */
1452 if (skb_queue_empty(&pch
->file
.xq
)) {
1453 read_lock_bh(&pch
->upl
);
1456 ppp_xmit_process(ppp
);
1457 read_unlock_bh(&pch
->upl
);
1462 * Receive-side routines.
1465 /* misuse a few fields of the skb for MP reconstruction */
1466 #define sequence priority
1467 #define BEbits cb[0]
1470 ppp_do_recv(struct ppp
*ppp
, struct sk_buff
*skb
, struct channel
*pch
)
1473 /* ppp->dev == 0 means interface is closing down */
1475 ppp_receive_frame(ppp
, skb
, pch
);
1478 ppp_recv_unlock(ppp
);
1482 ppp_input(struct ppp_channel
*chan
, struct sk_buff
*skb
)
1484 struct channel
*pch
= chan
->ppp
;
1487 if (pch
== 0 || skb
->len
== 0) {
1492 proto
= PPP_PROTO(skb
);
1493 read_lock_bh(&pch
->upl
);
1494 if (pch
->ppp
== 0 || proto
>= 0xc000 || proto
== PPP_CCPFRAG
) {
1495 /* put it on the channel queue */
1496 skb_queue_tail(&pch
->file
.rq
, skb
);
1497 /* drop old frames if queue too long */
1498 while (pch
->file
.rq
.qlen
> PPP_MAX_RQLEN
1499 && (skb
= skb_dequeue(&pch
->file
.rq
)) != 0)
1501 wake_up_interruptible(&pch
->file
.rwait
);
1503 ppp_do_recv(pch
->ppp
, skb
, pch
);
1505 read_unlock_bh(&pch
->upl
);
1508 /* Put a 0-length skb in the receive queue as an error indication */
1510 ppp_input_error(struct ppp_channel
*chan
, int code
)
1512 struct channel
*pch
= chan
->ppp
;
1513 struct sk_buff
*skb
;
1518 read_lock_bh(&pch
->upl
);
1519 if (pch
->ppp
!= 0) {
1520 skb
= alloc_skb(0, GFP_ATOMIC
);
1522 skb
->len
= 0; /* probably unnecessary */
1524 ppp_do_recv(pch
->ppp
, skb
, pch
);
1527 read_unlock_bh(&pch
->upl
);
1531 * We come in here to process a received frame.
1532 * The receive side of the ppp unit is locked.
1535 ppp_receive_frame(struct ppp
*ppp
, struct sk_buff
*skb
, struct channel
*pch
)
1537 if (skb
->len
>= 2) {
1538 #ifdef CONFIG_PPP_MULTILINK
1539 /* XXX do channel-level decompression here */
1540 if (PPP_PROTO(skb
) == PPP_MP
)
1541 ppp_receive_mp_frame(ppp
, skb
, pch
);
1543 #endif /* CONFIG_PPP_MULTILINK */
1544 ppp_receive_nonmp_frame(ppp
, skb
);
1549 /* note: a 0-length skb is used as an error indication */
1550 ++ppp
->stats
.rx_length_errors
;
1553 ppp_receive_error(ppp
);
1557 ppp_receive_error(struct ppp
*ppp
)
1559 ++ppp
->stats
.rx_errors
;
1565 ppp_receive_nonmp_frame(struct ppp
*ppp
, struct sk_buff
*skb
)
1568 int proto
, len
, npi
;
1571 * Decompress the frame, if compressed.
1572 * Note that some decompressors need to see uncompressed frames
1573 * that come in as well as compressed frames.
1575 if (ppp
->rc_state
!= 0 && (ppp
->rstate
& SC_DECOMP_RUN
)
1576 && (ppp
->rstate
& (SC_DC_FERROR
| SC_DC_ERROR
)) == 0)
1577 skb
= ppp_decompress_frame(ppp
, skb
);
1579 if (ppp
->flags
& SC_MUST_COMP
&& ppp
->rstate
& SC_DC_FERROR
)
1582 proto
= PPP_PROTO(skb
);
1585 /* decompress VJ compressed packets */
1586 if (ppp
->vj
== 0 || (ppp
->flags
& SC_REJ_COMP_TCP
))
1589 if (skb_tailroom(skb
) < 124) {
1590 /* copy to a new sk_buff with more tailroom */
1591 ns
= dev_alloc_skb(skb
->len
+ 128);
1593 printk(KERN_ERR
"PPP: no memory (VJ decomp)\n");
1597 skb_copy_bits(skb
, 0, skb_put(ns
, skb
->len
), skb
->len
);
1602 skb
->ip_summed
= CHECKSUM_NONE
;
1604 len
= slhc_uncompress(ppp
->vj
, skb
->data
+ 2, skb
->len
- 2);
1606 printk(KERN_DEBUG
"PPP: VJ decompression error\n");
1611 skb_put(skb
, len
- skb
->len
);
1612 else if (len
< skb
->len
)
1617 case PPP_VJC_UNCOMP
:
1618 if (ppp
->vj
== 0 || (ppp
->flags
& SC_REJ_COMP_TCP
))
1621 /* Until we fix the decompressor need to make sure
1622 * data portion is linear.
1624 if (!pskb_may_pull(skb
, skb
->len
))
1627 if (slhc_remember(ppp
->vj
, skb
->data
+ 2, skb
->len
- 2) <= 0) {
1628 printk(KERN_ERR
"PPP: VJ uncompressed error\n");
1635 ppp_ccp_peek(ppp
, skb
, 1);
1639 ++ppp
->stats
.rx_packets
;
1640 ppp
->stats
.rx_bytes
+= skb
->len
- 2;
1642 npi
= proto_to_npindex(proto
);
1644 /* control or unknown frame - pass it to pppd */
1645 skb_queue_tail(&ppp
->file
.rq
, skb
);
1646 /* limit queue length by dropping old frames */
1647 while (ppp
->file
.rq
.qlen
> PPP_MAX_RQLEN
1648 && (skb
= skb_dequeue(&ppp
->file
.rq
)) != 0)
1650 /* wake up any process polling or blocking on read */
1651 wake_up_interruptible(&ppp
->file
.rwait
);
1654 /* network protocol frame - give it to the kernel */
1656 #ifdef CONFIG_PPP_FILTER
1657 /* check if the packet passes the pass and active filters */
1658 /* the filter instructions are constructed assuming
1659 a four-byte PPP header on each packet */
1660 *skb_push(skb
, 2) = 0;
1661 if (ppp
->pass_filter
1662 && sk_run_filter(skb
, ppp
->pass_filter
,
1663 ppp
->pass_len
) == 0) {
1665 printk(KERN_DEBUG
"PPP: inbound frame not passed\n");
1669 if (!(ppp
->active_filter
1670 && sk_run_filter(skb
, ppp
->active_filter
,
1671 ppp
->active_len
) == 0))
1672 ppp
->last_recv
= jiffies
;
1675 ppp
->last_recv
= jiffies
;
1676 #endif /* CONFIG_PPP_FILTER */
1678 if ((ppp
->dev
->flags
& IFF_UP
) == 0
1679 || ppp
->npmode
[npi
] != NPMODE_PASS
) {
1682 /* chop off protocol */
1683 skb_pull_rcsum(skb
, 2);
1684 skb
->dev
= ppp
->dev
;
1685 skb
->protocol
= htons(npindex_to_ethertype
[npi
]);
1686 skb_reset_mac_header(skb
);
1688 ppp
->dev
->last_rx
= jiffies
;
1695 ppp_receive_error(ppp
);
1698 static struct sk_buff
*
1699 ppp_decompress_frame(struct ppp
*ppp
, struct sk_buff
*skb
)
1701 int proto
= PPP_PROTO(skb
);
1705 /* Until we fix all the decompressor's need to make sure
1706 * data portion is linear.
1708 if (!pskb_may_pull(skb
, skb
->len
))
1711 if (proto
== PPP_COMP
) {
1712 ns
= dev_alloc_skb(ppp
->mru
+ PPP_HDRLEN
);
1714 printk(KERN_ERR
"ppp_decompress_frame: no memory\n");
1717 /* the decompressor still expects the A/C bytes in the hdr */
1718 len
= ppp
->rcomp
->decompress(ppp
->rc_state
, skb
->data
- 2,
1719 skb
->len
+ 2, ns
->data
, ppp
->mru
+ PPP_HDRLEN
);
1721 /* Pass the compressed frame to pppd as an
1722 error indication. */
1723 if (len
== DECOMP_FATALERROR
)
1724 ppp
->rstate
|= SC_DC_FERROR
;
1732 skb_pull(skb
, 2); /* pull off the A/C bytes */
1735 /* Uncompressed frame - pass to decompressor so it
1736 can update its dictionary if necessary. */
1737 if (ppp
->rcomp
->incomp
)
1738 ppp
->rcomp
->incomp(ppp
->rc_state
, skb
->data
- 2,
1745 ppp
->rstate
|= SC_DC_ERROR
;
1746 ppp_receive_error(ppp
);
1750 #ifdef CONFIG_PPP_MULTILINK
1752 * Receive a multilink frame.
1753 * We put it on the reconstruction queue and then pull off
1754 * as many completed frames as we can.
1757 ppp_receive_mp_frame(struct ppp
*ppp
, struct sk_buff
*skb
, struct channel
*pch
)
1761 int mphdrlen
= (ppp
->flags
& SC_MP_SHORTSEQ
)? MPHDRLEN_SSN
: MPHDRLEN
;
1763 if (!pskb_may_pull(skb
, mphdrlen
) || ppp
->mrru
== 0)
1764 goto err
; /* no good, throw it away */
1766 /* Decode sequence number and begin/end bits */
1767 if (ppp
->flags
& SC_MP_SHORTSEQ
) {
1768 seq
= ((skb
->data
[2] & 0x0f) << 8) | skb
->data
[3];
1771 seq
= (skb
->data
[3] << 16) | (skb
->data
[4] << 8)| skb
->data
[5];
1774 skb
->BEbits
= skb
->data
[2];
1775 skb_pull(skb
, mphdrlen
); /* pull off PPP and MP headers */
1778 * Do protocol ID decompression on the first fragment of each packet.
1780 if ((skb
->BEbits
& B
) && (skb
->data
[0] & 1))
1781 *skb_push(skb
, 1) = 0;
1784 * Expand sequence number to 32 bits, making it as close
1785 * as possible to ppp->minseq.
1787 seq
|= ppp
->minseq
& ~mask
;
1788 if ((int)(ppp
->minseq
- seq
) > (int)(mask
>> 1))
1790 else if ((int)(seq
- ppp
->minseq
) > (int)(mask
>> 1))
1791 seq
-= mask
+ 1; /* should never happen */
1792 skb
->sequence
= seq
;
1796 * If this packet comes before the next one we were expecting,
1799 if (seq_before(seq
, ppp
->nextseq
)) {
1801 ++ppp
->stats
.rx_dropped
;
1802 ppp_receive_error(ppp
);
1807 * Reevaluate minseq, the minimum over all channels of the
1808 * last sequence number received on each channel. Because of
1809 * the increasing sequence number rule, we know that any fragment
1810 * before `minseq' which hasn't arrived is never going to arrive.
1811 * The list of channels can't change because we have the receive
1812 * side of the ppp unit locked.
1814 list_for_each_entry(ch
, &ppp
->channels
, clist
) {
1815 if (seq_before(ch
->lastseq
, seq
))
1818 if (seq_before(ppp
->minseq
, seq
))
1821 /* Put the fragment on the reconstruction queue */
1822 ppp_mp_insert(ppp
, skb
);
1824 /* If the queue is getting long, don't wait any longer for packets
1825 before the start of the queue. */
1826 if (skb_queue_len(&ppp
->mrq
) >= PPP_MP_MAX_QLEN
1827 && seq_before(ppp
->minseq
, ppp
->mrq
.next
->sequence
))
1828 ppp
->minseq
= ppp
->mrq
.next
->sequence
;
1830 /* Pull completed packets off the queue and receive them. */
1831 while ((skb
= ppp_mp_reconstruct(ppp
)) != 0)
1832 ppp_receive_nonmp_frame(ppp
, skb
);
1838 ppp_receive_error(ppp
);
1842 * Insert a fragment on the MP reconstruction queue.
1843 * The queue is ordered by increasing sequence number.
1846 ppp_mp_insert(struct ppp
*ppp
, struct sk_buff
*skb
)
1849 struct sk_buff_head
*list
= &ppp
->mrq
;
1850 u32 seq
= skb
->sequence
;
1852 /* N.B. we don't need to lock the list lock because we have the
1853 ppp unit receive-side lock. */
1854 for (p
= list
->next
; p
!= (struct sk_buff
*)list
; p
= p
->next
)
1855 if (seq_before(seq
, p
->sequence
))
1857 __skb_insert(skb
, p
->prev
, p
, list
);
1861 * Reconstruct a packet from the MP fragment queue.
1862 * We go through increasing sequence numbers until we find a
1863 * complete packet, or we get to the sequence number for a fragment
1864 * which hasn't arrived but might still do so.
1867 ppp_mp_reconstruct(struct ppp
*ppp
)
1869 u32 seq
= ppp
->nextseq
;
1870 u32 minseq
= ppp
->minseq
;
1871 struct sk_buff_head
*list
= &ppp
->mrq
;
1872 struct sk_buff
*p
, *next
;
1873 struct sk_buff
*head
, *tail
;
1874 struct sk_buff
*skb
= NULL
;
1875 int lost
= 0, len
= 0;
1877 if (ppp
->mrru
== 0) /* do nothing until mrru is set */
1881 for (p
= head
; p
!= (struct sk_buff
*) list
; p
= next
) {
1883 if (seq_before(p
->sequence
, seq
)) {
1884 /* this can't happen, anyway ignore the skb */
1885 printk(KERN_ERR
"ppp_mp_reconstruct bad seq %u < %u\n",
1890 if (p
->sequence
!= seq
) {
1891 /* Fragment `seq' is missing. If it is after
1892 minseq, it might arrive later, so stop here. */
1893 if (seq_after(seq
, minseq
))
1895 /* Fragment `seq' is lost, keep going. */
1897 seq
= seq_before(minseq
, p
->sequence
)?
1898 minseq
+ 1: p
->sequence
;
1904 * At this point we know that all the fragments from
1905 * ppp->nextseq to seq are either present or lost.
1906 * Also, there are no complete packets in the queue
1907 * that have no missing fragments and end before this
1911 /* B bit set indicates this fragment starts a packet */
1912 if (p
->BEbits
& B
) {
1920 /* Got a complete packet yet? */
1921 if (lost
== 0 && (p
->BEbits
& E
) && (head
->BEbits
& B
)) {
1922 if (len
> ppp
->mrru
+ 2) {
1923 ++ppp
->stats
.rx_length_errors
;
1924 printk(KERN_DEBUG
"PPP: reconstructed packet"
1925 " is too long (%d)\n", len
);
1926 } else if (p
== head
) {
1927 /* fragment is complete packet - reuse skb */
1931 } else if ((skb
= dev_alloc_skb(len
)) == NULL
) {
1932 ++ppp
->stats
.rx_missed_errors
;
1933 printk(KERN_DEBUG
"PPP: no memory for "
1934 "reconstructed packet");
1939 ppp
->nextseq
= seq
+ 1;
1943 * If this is the ending fragment of a packet,
1944 * and we haven't found a complete valid packet yet,
1945 * we can discard up to and including this fragment.
1953 /* If we have a complete packet, copy it all into one skb. */
1955 /* If we have discarded any fragments,
1956 signal a receive error. */
1957 if (head
->sequence
!= ppp
->nextseq
) {
1959 printk(KERN_DEBUG
" missed pkts %u..%u\n",
1960 ppp
->nextseq
, head
->sequence
-1);
1961 ++ppp
->stats
.rx_dropped
;
1962 ppp_receive_error(ppp
);
1966 /* copy to a single skb */
1967 for (p
= head
; p
!= tail
->next
; p
= p
->next
)
1968 skb_copy_bits(p
, 0, skb_put(skb
, p
->len
), p
->len
);
1969 ppp
->nextseq
= tail
->sequence
+ 1;
1973 /* Discard all the skbuffs that we have copied the data out of
1974 or that we can't use. */
1975 while ((p
= list
->next
) != head
) {
1976 __skb_unlink(p
, list
);
1982 #endif /* CONFIG_PPP_MULTILINK */
1985 * Channel interface.
1989 * Create a new, unattached ppp channel.
1992 ppp_register_channel(struct ppp_channel
*chan
)
1994 struct channel
*pch
;
1996 pch
= kzalloc(sizeof(struct channel
), GFP_KERNEL
);
2002 init_ppp_file(&pch
->file
, CHANNEL
);
2003 pch
->file
.hdrlen
= chan
->hdrlen
;
2004 #ifdef CONFIG_PPP_MULTILINK
2006 #endif /* CONFIG_PPP_MULTILINK */
2007 init_rwsem(&pch
->chan_sem
);
2008 spin_lock_init(&pch
->downl
);
2009 rwlock_init(&pch
->upl
);
2010 spin_lock_bh(&all_channels_lock
);
2011 pch
->file
.index
= ++last_channel_index
;
2012 list_add(&pch
->list
, &new_channels
);
2013 atomic_inc(&channel_count
);
2014 spin_unlock_bh(&all_channels_lock
);
2019 * Return the index of a channel.
2021 int ppp_channel_index(struct ppp_channel
*chan
)
2023 struct channel
*pch
= chan
->ppp
;
2026 return pch
->file
.index
;
2031 * Return the PPP unit number to which a channel is connected.
2033 int ppp_unit_number(struct ppp_channel
*chan
)
2035 struct channel
*pch
= chan
->ppp
;
2039 read_lock_bh(&pch
->upl
);
2041 unit
= pch
->ppp
->file
.index
;
2042 read_unlock_bh(&pch
->upl
);
2048 * Disconnect a channel from the generic layer.
2049 * This must be called in process context.
2052 ppp_unregister_channel(struct ppp_channel
*chan
)
2054 struct channel
*pch
= chan
->ppp
;
2057 return; /* should never happen */
2061 * This ensures that we have returned from any calls into the
2062 * the channel's start_xmit or ioctl routine before we proceed.
2064 down_write(&pch
->chan_sem
);
2065 spin_lock_bh(&pch
->downl
);
2067 spin_unlock_bh(&pch
->downl
);
2068 up_write(&pch
->chan_sem
);
2069 ppp_disconnect_channel(pch
);
2070 spin_lock_bh(&all_channels_lock
);
2071 list_del(&pch
->list
);
2072 spin_unlock_bh(&all_channels_lock
);
2074 wake_up_interruptible(&pch
->file
.rwait
);
2075 if (atomic_dec_and_test(&pch
->file
.refcnt
))
2076 ppp_destroy_channel(pch
);
2080 * Callback from a channel when it can accept more to transmit.
2081 * This should be called at BH/softirq level, not interrupt level.
2084 ppp_output_wakeup(struct ppp_channel
*chan
)
2086 struct channel
*pch
= chan
->ppp
;
2090 ppp_channel_push(pch
);
2094 * Compression control.
2097 /* Process the PPPIOCSCOMPRESS ioctl. */
2099 ppp_set_compress(struct ppp
*ppp
, unsigned long arg
)
2102 struct compressor
*cp
, *ocomp
;
2103 struct ppp_option_data data
;
2104 void *state
, *ostate
;
2105 unsigned char ccp_option
[CCP_MAX_OPTION_LENGTH
];
2108 if (copy_from_user(&data
, (void __user
*) arg
, sizeof(data
))
2109 || (data
.length
<= CCP_MAX_OPTION_LENGTH
2110 && copy_from_user(ccp_option
, (void __user
*) data
.ptr
, data
.length
)))
2113 if (data
.length
> CCP_MAX_OPTION_LENGTH
2114 || ccp_option
[1] < 2 || ccp_option
[1] > data
.length
)
2117 cp
= find_compressor(ccp_option
[0]);
2120 request_module("ppp-compress-%d", ccp_option
[0]);
2121 cp
= find_compressor(ccp_option
[0]);
2123 #endif /* CONFIG_KMOD */
2128 if (data
.transmit
) {
2129 state
= cp
->comp_alloc(ccp_option
, data
.length
);
2132 ppp
->xstate
&= ~SC_COMP_RUN
;
2134 ostate
= ppp
->xc_state
;
2136 ppp
->xc_state
= state
;
2137 ppp_xmit_unlock(ppp
);
2139 ocomp
->comp_free(ostate
);
2140 module_put(ocomp
->owner
);
2144 module_put(cp
->owner
);
2147 state
= cp
->decomp_alloc(ccp_option
, data
.length
);
2150 ppp
->rstate
&= ~SC_DECOMP_RUN
;
2152 ostate
= ppp
->rc_state
;
2154 ppp
->rc_state
= state
;
2155 ppp_recv_unlock(ppp
);
2157 ocomp
->decomp_free(ostate
);
2158 module_put(ocomp
->owner
);
2162 module_put(cp
->owner
);
2170 * Look at a CCP packet and update our state accordingly.
2171 * We assume the caller has the xmit or recv path locked.
2174 ppp_ccp_peek(struct ppp
*ppp
, struct sk_buff
*skb
, int inbound
)
2179 if (!pskb_may_pull(skb
, CCP_HDRLEN
+ 2))
2180 return; /* no header */
2183 switch (CCP_CODE(dp
)) {
2186 /* A ConfReq starts negotiation of compression
2187 * in one direction of transmission,
2188 * and hence brings it down...but which way?
2191 * A ConfReq indicates what the sender would like to receive
2194 /* He is proposing what I should send */
2195 ppp
->xstate
&= ~SC_COMP_RUN
;
2197 /* I am proposing to what he should send */
2198 ppp
->rstate
&= ~SC_DECOMP_RUN
;
2205 * CCP is going down, both directions of transmission
2207 ppp
->rstate
&= ~SC_DECOMP_RUN
;
2208 ppp
->xstate
&= ~SC_COMP_RUN
;
2212 if ((ppp
->flags
& (SC_CCP_OPEN
| SC_CCP_UP
)) != SC_CCP_OPEN
)
2214 len
= CCP_LENGTH(dp
);
2215 if (!pskb_may_pull(skb
, len
+ 2))
2216 return; /* too short */
2219 if (len
< CCP_OPT_MINLEN
|| len
< CCP_OPT_LENGTH(dp
))
2222 /* we will start receiving compressed packets */
2223 if (ppp
->rc_state
== 0)
2225 if (ppp
->rcomp
->decomp_init(ppp
->rc_state
, dp
, len
,
2226 ppp
->file
.index
, 0, ppp
->mru
, ppp
->debug
)) {
2227 ppp
->rstate
|= SC_DECOMP_RUN
;
2228 ppp
->rstate
&= ~(SC_DC_ERROR
| SC_DC_FERROR
);
2231 /* we will soon start sending compressed packets */
2232 if (ppp
->xc_state
== 0)
2234 if (ppp
->xcomp
->comp_init(ppp
->xc_state
, dp
, len
,
2235 ppp
->file
.index
, 0, ppp
->debug
))
2236 ppp
->xstate
|= SC_COMP_RUN
;
2241 /* reset the [de]compressor */
2242 if ((ppp
->flags
& SC_CCP_UP
) == 0)
2245 if (ppp
->rc_state
&& (ppp
->rstate
& SC_DECOMP_RUN
)) {
2246 ppp
->rcomp
->decomp_reset(ppp
->rc_state
);
2247 ppp
->rstate
&= ~SC_DC_ERROR
;
2250 if (ppp
->xc_state
&& (ppp
->xstate
& SC_COMP_RUN
))
2251 ppp
->xcomp
->comp_reset(ppp
->xc_state
);
2257 /* Free up compression resources. */
2259 ppp_ccp_closed(struct ppp
*ppp
)
2261 void *xstate
, *rstate
;
2262 struct compressor
*xcomp
, *rcomp
;
2265 ppp
->flags
&= ~(SC_CCP_OPEN
| SC_CCP_UP
);
2268 xstate
= ppp
->xc_state
;
2269 ppp
->xc_state
= NULL
;
2272 rstate
= ppp
->rc_state
;
2273 ppp
->rc_state
= NULL
;
2277 xcomp
->comp_free(xstate
);
2278 module_put(xcomp
->owner
);
2281 rcomp
->decomp_free(rstate
);
2282 module_put(rcomp
->owner
);
2286 /* List of compressors. */
2287 static LIST_HEAD(compressor_list
);
2288 static DEFINE_SPINLOCK(compressor_list_lock
);
2290 struct compressor_entry
{
2291 struct list_head list
;
2292 struct compressor
*comp
;
2295 static struct compressor_entry
*
2296 find_comp_entry(int proto
)
2298 struct compressor_entry
*ce
;
2300 list_for_each_entry(ce
, &compressor_list
, list
) {
2301 if (ce
->comp
->compress_proto
== proto
)
2307 /* Register a compressor */
2309 ppp_register_compressor(struct compressor
*cp
)
2311 struct compressor_entry
*ce
;
2313 spin_lock(&compressor_list_lock
);
2315 if (find_comp_entry(cp
->compress_proto
) != 0)
2318 ce
= kmalloc(sizeof(struct compressor_entry
), GFP_ATOMIC
);
2323 list_add(&ce
->list
, &compressor_list
);
2325 spin_unlock(&compressor_list_lock
);
2329 /* Unregister a compressor */
2331 ppp_unregister_compressor(struct compressor
*cp
)
2333 struct compressor_entry
*ce
;
2335 spin_lock(&compressor_list_lock
);
2336 ce
= find_comp_entry(cp
->compress_proto
);
2337 if (ce
!= 0 && ce
->comp
== cp
) {
2338 list_del(&ce
->list
);
2341 spin_unlock(&compressor_list_lock
);
2344 /* Find a compressor. */
2345 static struct compressor
*
2346 find_compressor(int type
)
2348 struct compressor_entry
*ce
;
2349 struct compressor
*cp
= NULL
;
2351 spin_lock(&compressor_list_lock
);
2352 ce
= find_comp_entry(type
);
2355 if (!try_module_get(cp
->owner
))
2358 spin_unlock(&compressor_list_lock
);
2363 * Miscelleneous stuff.
2367 ppp_get_stats(struct ppp
*ppp
, struct ppp_stats
*st
)
2369 struct slcompress
*vj
= ppp
->vj
;
2371 memset(st
, 0, sizeof(*st
));
2372 st
->p
.ppp_ipackets
= ppp
->stats
.rx_packets
;
2373 st
->p
.ppp_ierrors
= ppp
->stats
.rx_errors
;
2374 st
->p
.ppp_ibytes
= ppp
->stats
.rx_bytes
;
2375 st
->p
.ppp_opackets
= ppp
->stats
.tx_packets
;
2376 st
->p
.ppp_oerrors
= ppp
->stats
.tx_errors
;
2377 st
->p
.ppp_obytes
= ppp
->stats
.tx_bytes
;
2380 st
->vj
.vjs_packets
= vj
->sls_o_compressed
+ vj
->sls_o_uncompressed
;
2381 st
->vj
.vjs_compressed
= vj
->sls_o_compressed
;
2382 st
->vj
.vjs_searches
= vj
->sls_o_searches
;
2383 st
->vj
.vjs_misses
= vj
->sls_o_misses
;
2384 st
->vj
.vjs_errorin
= vj
->sls_i_error
;
2385 st
->vj
.vjs_tossed
= vj
->sls_i_tossed
;
2386 st
->vj
.vjs_uncompressedin
= vj
->sls_i_uncompressed
;
2387 st
->vj
.vjs_compressedin
= vj
->sls_i_compressed
;
2391 * Stuff for handling the lists of ppp units and channels
2392 * and for initialization.
2396 * Create a new ppp interface unit. Fails if it can't allocate memory
2397 * or if there is already a unit with the requested number.
2398 * unit == -1 means allocate a new number.
2401 ppp_create_interface(int unit
, int *retp
)
2404 struct net_device
*dev
= NULL
;
2408 ppp
= kzalloc(sizeof(struct ppp
), GFP_KERNEL
);
2411 dev
= alloc_netdev(0, "", ppp_setup
);
2416 init_ppp_file(&ppp
->file
, INTERFACE
);
2417 ppp
->file
.hdrlen
= PPP_HDRLEN
- 2; /* don't count proto bytes */
2418 for (i
= 0; i
< NUM_NP
; ++i
)
2419 ppp
->npmode
[i
] = NPMODE_PASS
;
2420 INIT_LIST_HEAD(&ppp
->channels
);
2421 spin_lock_init(&ppp
->rlock
);
2422 spin_lock_init(&ppp
->wlock
);
2423 #ifdef CONFIG_PPP_MULTILINK
2425 skb_queue_head_init(&ppp
->mrq
);
2426 #endif /* CONFIG_PPP_MULTILINK */
2430 dev
->hard_start_xmit
= ppp_start_xmit
;
2431 dev
->get_stats
= ppp_net_stats
;
2432 dev
->do_ioctl
= ppp_net_ioctl
;
2435 mutex_lock(&all_ppp_mutex
);
2437 unit
= cardmap_find_first_free(all_ppp_units
);
2438 else if (cardmap_get(all_ppp_units
, unit
) != NULL
)
2439 goto out2
; /* unit already exists */
2441 /* Initialize the new ppp unit */
2442 ppp
->file
.index
= unit
;
2443 sprintf(dev
->name
, "ppp%d", unit
);
2445 ret
= register_netdev(dev
);
2447 printk(KERN_ERR
"PPP: couldn't register device %s (%d)\n",
2452 atomic_inc(&ppp_unit_count
);
2453 ret
= cardmap_set(&all_ppp_units
, unit
, ppp
);
2457 mutex_unlock(&all_ppp_mutex
);
2462 atomic_dec(&ppp_unit_count
);
2464 mutex_unlock(&all_ppp_mutex
);
2474 * Initialize a ppp_file structure.
2477 init_ppp_file(struct ppp_file
*pf
, int kind
)
2480 skb_queue_head_init(&pf
->xq
);
2481 skb_queue_head_init(&pf
->rq
);
2482 atomic_set(&pf
->refcnt
, 1);
2483 init_waitqueue_head(&pf
->rwait
);
2487 * Take down a ppp interface unit - called when the owning file
2488 * (the one that created the unit) is closed or detached.
2490 static void ppp_shutdown_interface(struct ppp
*ppp
)
2492 struct net_device
*dev
;
2494 mutex_lock(&all_ppp_mutex
);
2499 /* This will call dev_close() for us. */
2501 unregister_netdev(dev
);
2504 cardmap_set(&all_ppp_units
, ppp
->file
.index
, NULL
);
2507 wake_up_interruptible(&ppp
->file
.rwait
);
2508 mutex_unlock(&all_ppp_mutex
);
2512 * Free the memory used by a ppp unit. This is only called once
2513 * there are no channels connected to the unit and no file structs
2514 * that reference the unit.
2516 static void ppp_destroy_interface(struct ppp
*ppp
)
2518 atomic_dec(&ppp_unit_count
);
2520 if (!ppp
->file
.dead
|| ppp
->n_channels
) {
2521 /* "can't happen" */
2522 printk(KERN_ERR
"ppp: destroying ppp struct %p but dead=%d "
2523 "n_channels=%d !\n", ppp
, ppp
->file
.dead
,
2528 ppp_ccp_closed(ppp
);
2533 skb_queue_purge(&ppp
->file
.xq
);
2534 skb_queue_purge(&ppp
->file
.rq
);
2535 #ifdef CONFIG_PPP_MULTILINK
2536 skb_queue_purge(&ppp
->mrq
);
2537 #endif /* CONFIG_PPP_MULTILINK */
2538 #ifdef CONFIG_PPP_FILTER
2539 kfree(ppp
->pass_filter
);
2540 ppp
->pass_filter
= NULL
;
2541 kfree(ppp
->active_filter
);
2542 ppp
->active_filter
= NULL
;
2543 #endif /* CONFIG_PPP_FILTER */
2545 if (ppp
->xmit_pending
)
2546 kfree_skb(ppp
->xmit_pending
);
2552 * Locate an existing ppp unit.
2553 * The caller should have locked the all_ppp_mutex.
2556 ppp_find_unit(int unit
)
2558 return cardmap_get(all_ppp_units
, unit
);
2562 * Locate an existing ppp channel.
2563 * The caller should have locked the all_channels_lock.
2564 * First we look in the new_channels list, then in the
2565 * all_channels list. If found in the new_channels list,
2566 * we move it to the all_channels list. This is for speed
2567 * when we have a lot of channels in use.
2569 static struct channel
*
2570 ppp_find_channel(int unit
)
2572 struct channel
*pch
;
2574 list_for_each_entry(pch
, &new_channels
, list
) {
2575 if (pch
->file
.index
== unit
) {
2576 list_move(&pch
->list
, &all_channels
);
2580 list_for_each_entry(pch
, &all_channels
, list
) {
2581 if (pch
->file
.index
== unit
)
2588 * Connect a PPP channel to a PPP interface unit.
2591 ppp_connect_channel(struct channel
*pch
, int unit
)
2597 mutex_lock(&all_ppp_mutex
);
2598 ppp
= ppp_find_unit(unit
);
2601 write_lock_bh(&pch
->upl
);
2607 if (pch
->file
.hdrlen
> ppp
->file
.hdrlen
)
2608 ppp
->file
.hdrlen
= pch
->file
.hdrlen
;
2609 hdrlen
= pch
->file
.hdrlen
+ 2; /* for protocol bytes */
2610 if (ppp
->dev
&& hdrlen
> ppp
->dev
->hard_header_len
)
2611 ppp
->dev
->hard_header_len
= hdrlen
;
2612 list_add_tail(&pch
->clist
, &ppp
->channels
);
2615 atomic_inc(&ppp
->file
.refcnt
);
2620 write_unlock_bh(&pch
->upl
);
2622 mutex_unlock(&all_ppp_mutex
);
2627 * Disconnect a channel from its ppp unit.
2630 ppp_disconnect_channel(struct channel
*pch
)
2635 write_lock_bh(&pch
->upl
);
2638 write_unlock_bh(&pch
->upl
);
2640 /* remove it from the ppp unit's list */
2642 list_del(&pch
->clist
);
2643 if (--ppp
->n_channels
== 0)
2644 wake_up_interruptible(&ppp
->file
.rwait
);
2646 if (atomic_dec_and_test(&ppp
->file
.refcnt
))
2647 ppp_destroy_interface(ppp
);
2654 * Free up the resources used by a ppp channel.
2656 static void ppp_destroy_channel(struct channel
*pch
)
2658 atomic_dec(&channel_count
);
2660 if (!pch
->file
.dead
) {
2661 /* "can't happen" */
2662 printk(KERN_ERR
"ppp: destroying undead channel %p !\n",
2666 skb_queue_purge(&pch
->file
.xq
);
2667 skb_queue_purge(&pch
->file
.rq
);
2671 static void __exit
ppp_cleanup(void)
2673 /* should never happen */
2674 if (atomic_read(&ppp_unit_count
) || atomic_read(&channel_count
))
2675 printk(KERN_ERR
"PPP: removing module but units remain!\n");
2676 cardmap_destroy(&all_ppp_units
);
2677 if (unregister_chrdev(PPP_MAJOR
, "ppp") != 0)
2678 printk(KERN_ERR
"PPP: failed to unregister PPP device\n");
2679 device_destroy(ppp_class
, MKDEV(PPP_MAJOR
, 0));
2680 class_destroy(ppp_class
);
2684 * Cardmap implementation.
2686 static void *cardmap_get(struct cardmap
*map
, unsigned int nr
)
2691 for (p
= map
; p
!= NULL
; ) {
2692 if ((i
= nr
>> p
->shift
) >= CARDMAP_WIDTH
)
2696 nr
&= ~(CARDMAP_MASK
<< p
->shift
);
2702 static int cardmap_set(struct cardmap
**pmap
, unsigned int nr
, void *ptr
)
2708 if (p
== NULL
|| (nr
>> p
->shift
) >= CARDMAP_WIDTH
) {
2710 /* need a new top level */
2711 struct cardmap
*np
= kzalloc(sizeof(*np
), GFP_KERNEL
);
2716 np
->shift
= p
->shift
+ CARDMAP_ORDER
;
2721 } while ((nr
>> p
->shift
) >= CARDMAP_WIDTH
);
2724 while (p
->shift
> 0) {
2725 i
= (nr
>> p
->shift
) & CARDMAP_MASK
;
2726 if (p
->ptr
[i
] == NULL
) {
2727 struct cardmap
*np
= kzalloc(sizeof(*np
), GFP_KERNEL
);
2730 np
->shift
= p
->shift
- CARDMAP_ORDER
;
2735 clear_bit(i
, &p
->inuse
);
2738 i
= nr
& CARDMAP_MASK
;
2741 set_bit(i
, &p
->inuse
);
2743 clear_bit(i
, &p
->inuse
);
2749 static unsigned int cardmap_find_first_free(struct cardmap
*map
)
2752 unsigned int nr
= 0;
2755 if ((p
= map
) == NULL
)
2758 i
= find_first_zero_bit(&p
->inuse
, CARDMAP_WIDTH
);
2759 if (i
>= CARDMAP_WIDTH
) {
2760 if (p
->parent
== NULL
)
2761 return CARDMAP_WIDTH
<< p
->shift
;
2763 i
= (nr
>> p
->shift
) & CARDMAP_MASK
;
2764 set_bit(i
, &p
->inuse
);
2767 nr
= (nr
& (~CARDMAP_MASK
<< p
->shift
)) | (i
<< p
->shift
);
2768 if (p
->shift
== 0 || p
->ptr
[i
] == NULL
)
2774 static void cardmap_destroy(struct cardmap
**pmap
)
2776 struct cardmap
*p
, *np
;
2779 for (p
= *pmap
; p
!= NULL
; p
= np
) {
2780 if (p
->shift
!= 0) {
2781 for (i
= 0; i
< CARDMAP_WIDTH
; ++i
)
2782 if (p
->ptr
[i
] != NULL
)
2784 if (i
< CARDMAP_WIDTH
) {
2796 /* Module/initialization stuff */
2798 module_init(ppp_init
);
2799 module_exit(ppp_cleanup
);
2801 EXPORT_SYMBOL(ppp_register_channel
);
2802 EXPORT_SYMBOL(ppp_unregister_channel
);
2803 EXPORT_SYMBOL(ppp_channel_index
);
2804 EXPORT_SYMBOL(ppp_unit_number
);
2805 EXPORT_SYMBOL(ppp_input
);
2806 EXPORT_SYMBOL(ppp_input_error
);
2807 EXPORT_SYMBOL(ppp_output_wakeup
);
2808 EXPORT_SYMBOL(ppp_register_compressor
);
2809 EXPORT_SYMBOL(ppp_unregister_compressor
);
2810 MODULE_LICENSE("GPL");
2811 MODULE_ALIAS_CHARDEV_MAJOR(PPP_MAJOR
);
2812 MODULE_ALIAS("/dev/ppp");