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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Ralf Baechle815f62b2005-08-24 18:06:36 +01002 * This program is free software; you can distribute it and/or modify it
3 * under the terms of the GNU General Public License (Version 2) as
4 * published by the Free Software Foundation.
Linus Torvalds1da177e2005-04-16 15:20:36 -07005 *
Ralf Baechle815f62b2005-08-24 18:06:36 +01006 * This program is distributed in the hope it will be useful, but WITHOUT
7 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
8 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
9 * for more details.
Linus Torvalds1da177e2005-04-16 15:20:36 -070010 *
Ralf Baechle815f62b2005-08-24 18:06:36 +010011 * You should have received a copy of the GNU General Public License along
Jeff Kirsheradf8d3f2013-12-06 06:28:47 -080012 * with this program; if not, see <http://www.gnu.org/licenses/>.
Linus Torvalds1da177e2005-04-16 15:20:36 -070013 *
Ralf Baechle815f62b2005-08-24 18:06:36 +010014 * Copyright (C) Hans Alblas PE1AYX <hans@esrac.ele.tue.nl>
15 * Copyright (C) 2004, 05 Ralf Baechle DL5RB <ralf@linux-mips.org>
Ralf Baechle5793f4b2005-10-14 14:28:09 +010016 * Copyright (C) 2004, 05 Thomas Osterried DL9SAU <thomas@x-berg.in-berlin.de>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include <linux/module.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070019#include <linux/bitops.h>
20#include <asm/uaccess.h>
Ralf Baechle5793f4b2005-10-14 14:28:09 +010021#include <linux/crc16.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include <linux/string.h>
23#include <linux/mm.h>
24#include <linux/interrupt.h>
25#include <linux/in.h>
26#include <linux/inet.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090027#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070028#include <linux/tty.h>
29#include <linux/errno.h>
30#include <linux/netdevice.h>
31#include <linux/major.h>
32#include <linux/init.h>
33#include <linux/rtnetlink.h>
34#include <linux/etherdevice.h>
35#include <linux/skbuff.h>
36#include <linux/if_arp.h>
Marcelo Feitoza Parisicd8749b2005-07-15 11:16:42 +010037#include <linux/jiffies.h>
Arnd Bergmann9646e7c2009-11-06 22:51:16 -080038#include <linux/compat.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070039
40#include <net/ax25.h>
41
Ralf Baechle815f62b2005-08-24 18:06:36 +010042#define AX_MTU 236
Linus Torvalds1da177e2005-04-16 15:20:36 -070043
Ralf Baechle815f62b2005-08-24 18:06:36 +010044/* SLIP/KISS protocol characters. */
45#define END 0300 /* indicates end of frame */
46#define ESC 0333 /* indicates byte stuffing */
47#define ESC_END 0334 /* ESC ESC_END means END 'data' */
48#define ESC_ESC 0335 /* ESC ESC_ESC means ESC 'data' */
Linus Torvalds1da177e2005-04-16 15:20:36 -070049
Ralf Baechle815f62b2005-08-24 18:06:36 +010050struct mkiss {
51 struct tty_struct *tty; /* ptr to TTY structure */
52 struct net_device *dev; /* easy for intr handling */
Linus Torvalds1da177e2005-04-16 15:20:36 -070053
Ralf Baechle815f62b2005-08-24 18:06:36 +010054 /* These are pointers to the malloc()ed frame buffers. */
55 spinlock_t buflock;/* lock for rbuf and xbuf */
56 unsigned char *rbuff; /* receiver buffer */
57 int rcount; /* received chars counter */
58 unsigned char *xbuff; /* transmitter buffer */
59 unsigned char *xhead; /* pointer to next byte to XMIT */
60 int xleft; /* bytes left in XMIT queue */
Linus Torvalds1da177e2005-04-16 15:20:36 -070061
Ralf Baechle815f62b2005-08-24 18:06:36 +010062 /* Detailed SLIP statistics. */
63 int mtu; /* Our mtu (to spot changes!) */
64 int buffsize; /* Max buffers sizes */
Linus Torvalds1da177e2005-04-16 15:20:36 -070065
Ralf Baechle815f62b2005-08-24 18:06:36 +010066 unsigned long flags; /* Flag values/ mode etc */
67 /* long req'd: used by set_bit --RR */
68#define AXF_INUSE 0 /* Channel in use */
69#define AXF_ESCAPE 1 /* ESC received */
70#define AXF_ERROR 2 /* Parity, etc. error */
71#define AXF_KEEPTEST 3 /* Keepalive test flag */
72#define AXF_OUTWAIT 4 /* is outpacket was flag */
Linus Torvalds1da177e2005-04-16 15:20:36 -070073
Ralf Baechle815f62b2005-08-24 18:06:36 +010074 int mode;
75 int crcmode; /* MW: for FlexNet, SMACK etc. */
Ralf Baechle5793f4b2005-10-14 14:28:09 +010076 int crcauto; /* CRC auto mode */
77
78#define CRC_MODE_NONE 0
79#define CRC_MODE_FLEX 1
80#define CRC_MODE_SMACK 2
81#define CRC_MODE_FLEX_TEST 3
82#define CRC_MODE_SMACK_TEST 4
Ralf Baechle815f62b2005-08-24 18:06:36 +010083
84 atomic_t refcnt;
85 struct semaphore dead_sem;
Linus Torvalds1da177e2005-04-16 15:20:36 -070086};
87
88/*---------------------------------------------------------------------------*/
89
Ralf Baechle815f62b2005-08-24 18:06:36 +010090static const unsigned short crc_flex_table[] = {
91 0x0f87, 0x1e0e, 0x2c95, 0x3d1c, 0x49a3, 0x582a, 0x6ab1, 0x7b38,
92 0x83cf, 0x9246, 0xa0dd, 0xb154, 0xc5eb, 0xd462, 0xe6f9, 0xf770,
93 0x1f06, 0x0e8f, 0x3c14, 0x2d9d, 0x5922, 0x48ab, 0x7a30, 0x6bb9,
94 0x934e, 0x82c7, 0xb05c, 0xa1d5, 0xd56a, 0xc4e3, 0xf678, 0xe7f1,
95 0x2e85, 0x3f0c, 0x0d97, 0x1c1e, 0x68a1, 0x7928, 0x4bb3, 0x5a3a,
96 0xa2cd, 0xb344, 0x81df, 0x9056, 0xe4e9, 0xf560, 0xc7fb, 0xd672,
97 0x3e04, 0x2f8d, 0x1d16, 0x0c9f, 0x7820, 0x69a9, 0x5b32, 0x4abb,
98 0xb24c, 0xa3c5, 0x915e, 0x80d7, 0xf468, 0xe5e1, 0xd77a, 0xc6f3,
99 0x4d83, 0x5c0a, 0x6e91, 0x7f18, 0x0ba7, 0x1a2e, 0x28b5, 0x393c,
100 0xc1cb, 0xd042, 0xe2d9, 0xf350, 0x87ef, 0x9666, 0xa4fd, 0xb574,
101 0x5d02, 0x4c8b, 0x7e10, 0x6f99, 0x1b26, 0x0aaf, 0x3834, 0x29bd,
102 0xd14a, 0xc0c3, 0xf258, 0xe3d1, 0x976e, 0x86e7, 0xb47c, 0xa5f5,
103 0x6c81, 0x7d08, 0x4f93, 0x5e1a, 0x2aa5, 0x3b2c, 0x09b7, 0x183e,
104 0xe0c9, 0xf140, 0xc3db, 0xd252, 0xa6ed, 0xb764, 0x85ff, 0x9476,
105 0x7c00, 0x6d89, 0x5f12, 0x4e9b, 0x3a24, 0x2bad, 0x1936, 0x08bf,
106 0xf048, 0xe1c1, 0xd35a, 0xc2d3, 0xb66c, 0xa7e5, 0x957e, 0x84f7,
107 0x8b8f, 0x9a06, 0xa89d, 0xb914, 0xcdab, 0xdc22, 0xeeb9, 0xff30,
108 0x07c7, 0x164e, 0x24d5, 0x355c, 0x41e3, 0x506a, 0x62f1, 0x7378,
109 0x9b0e, 0x8a87, 0xb81c, 0xa995, 0xdd2a, 0xcca3, 0xfe38, 0xefb1,
110 0x1746, 0x06cf, 0x3454, 0x25dd, 0x5162, 0x40eb, 0x7270, 0x63f9,
111 0xaa8d, 0xbb04, 0x899f, 0x9816, 0xeca9, 0xfd20, 0xcfbb, 0xde32,
112 0x26c5, 0x374c, 0x05d7, 0x145e, 0x60e1, 0x7168, 0x43f3, 0x527a,
113 0xba0c, 0xab85, 0x991e, 0x8897, 0xfc28, 0xeda1, 0xdf3a, 0xceb3,
114 0x3644, 0x27cd, 0x1556, 0x04df, 0x7060, 0x61e9, 0x5372, 0x42fb,
115 0xc98b, 0xd802, 0xea99, 0xfb10, 0x8faf, 0x9e26, 0xacbd, 0xbd34,
116 0x45c3, 0x544a, 0x66d1, 0x7758, 0x03e7, 0x126e, 0x20f5, 0x317c,
117 0xd90a, 0xc883, 0xfa18, 0xeb91, 0x9f2e, 0x8ea7, 0xbc3c, 0xadb5,
118 0x5542, 0x44cb, 0x7650, 0x67d9, 0x1366, 0x02ef, 0x3074, 0x21fd,
119 0xe889, 0xf900, 0xcb9b, 0xda12, 0xaead, 0xbf24, 0x8dbf, 0x9c36,
120 0x64c1, 0x7548, 0x47d3, 0x565a, 0x22e5, 0x336c, 0x01f7, 0x107e,
121 0xf808, 0xe981, 0xdb1a, 0xca93, 0xbe2c, 0xafa5, 0x9d3e, 0x8cb7,
122 0x7440, 0x65c9, 0x5752, 0x46db, 0x3264, 0x23ed, 0x1176, 0x00ff
123};
124
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125static unsigned short calc_crc_flex(unsigned char *cp, int size)
126{
Ralf Baechle815f62b2005-08-24 18:06:36 +0100127 unsigned short crc = 0xffff;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128
Ralf Baechle815f62b2005-08-24 18:06:36 +0100129 while (size--)
130 crc = (crc << 8) ^ crc_flex_table[((crc >> 8) ^ *cp++) & 0xff];
131
132 return crc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133}
134
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135static int check_crc_flex(unsigned char *cp, int size)
136{
Ralf Baechle815f62b2005-08-24 18:06:36 +0100137 unsigned short crc = 0xffff;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700138
Ralf Baechle815f62b2005-08-24 18:06:36 +0100139 if (size < 3)
140 return -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141
Ralf Baechle815f62b2005-08-24 18:06:36 +0100142 while (size--)
143 crc = (crc << 8) ^ crc_flex_table[((crc >> 8) ^ *cp++) & 0xff];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144
Ralf Baechle815f62b2005-08-24 18:06:36 +0100145 if ((crc & 0xffff) != 0x7070)
146 return -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147
Ralf Baechle815f62b2005-08-24 18:06:36 +0100148 return 0;
149}
150
Ralf Baechle5793f4b2005-10-14 14:28:09 +0100151static int check_crc_16(unsigned char *cp, int size)
152{
153 unsigned short crc = 0x0000;
154
155 if (size < 3)
156 return -1;
157
158 crc = crc16(0, cp, size);
159
160 if (crc != 0x0000)
161 return -1;
162
163 return 0;
164}
165
Ralf Baechle815f62b2005-08-24 18:06:36 +0100166/*
167 * Standard encapsulation
168 */
169
170static int kiss_esc(unsigned char *s, unsigned char *d, int len)
171{
172 unsigned char *ptr = d;
173 unsigned char c;
174
175 /*
176 * Send an initial END character to flush out any data that may have
177 * accumulated in the receiver due to line noise.
178 */
179
180 *ptr++ = END;
181
182 while (len-- > 0) {
183 switch (c = *s++) {
184 case END:
185 *ptr++ = ESC;
186 *ptr++ = ESC_END;
187 break;
188 case ESC:
189 *ptr++ = ESC;
190 *ptr++ = ESC_ESC;
191 break;
192 default:
193 *ptr++ = c;
194 break;
195 }
196 }
197
198 *ptr++ = END;
199
200 return ptr - d;
201}
202
203/*
204 * MW:
205 * OK its ugly, but tell me a better solution without copying the
206 * packet to a temporary buffer :-)
207 */
208static int kiss_esc_crc(unsigned char *s, unsigned char *d, unsigned short crc,
209 int len)
210{
211 unsigned char *ptr = d;
212 unsigned char c=0;
213
214 *ptr++ = END;
215 while (len > 0) {
216 if (len > 2)
217 c = *s++;
218 else if (len > 1)
219 c = crc >> 8;
220 else if (len > 0)
221 c = crc & 0xff;
222
223 len--;
224
225 switch (c) {
226 case END:
227 *ptr++ = ESC;
228 *ptr++ = ESC_END;
229 break;
230 case ESC:
231 *ptr++ = ESC;
232 *ptr++ = ESC_ESC;
233 break;
234 default:
235 *ptr++ = c;
236 break;
237 }
238 }
239 *ptr++ = END;
240
241 return ptr - d;
242}
243
244/* Send one completely decapsulated AX.25 packet to the AX.25 layer. */
245static void ax_bump(struct mkiss *ax)
246{
247 struct sk_buff *skb;
248 int count;
249
250 spin_lock_bh(&ax->buflock);
251 if (ax->rbuff[0] > 0x0f) {
Ralf Baechle5793f4b2005-10-14 14:28:09 +0100252 if (ax->rbuff[0] & 0x80) {
253 if (check_crc_16(ax->rbuff, ax->rcount) < 0) {
Stephen Hemmingerddbe9a62009-01-09 13:01:40 +0000254 ax->dev->stats.rx_errors++;
Ralf Baechle5793f4b2005-10-14 14:28:09 +0100255 spin_unlock_bh(&ax->buflock);
256
Ralf Baechle815f62b2005-08-24 18:06:36 +0100257 return;
258 }
Ralf Baechle5793f4b2005-10-14 14:28:09 +0100259 if (ax->crcmode != CRC_MODE_SMACK && ax->crcauto) {
260 printk(KERN_INFO
Ralf Baechle7b1401c2009-10-01 14:48:25 -0700261 "mkiss: %s: Switching to crc-smack\n",
Ralf Baechle5793f4b2005-10-14 14:28:09 +0100262 ax->dev->name);
263 ax->crcmode = CRC_MODE_SMACK;
264 }
Ralf Baechle815f62b2005-08-24 18:06:36 +0100265 ax->rcount -= 2;
Ralf Baechle5793f4b2005-10-14 14:28:09 +0100266 *ax->rbuff &= ~0x80;
267 } else if (ax->rbuff[0] & 0x20) {
268 if (check_crc_flex(ax->rbuff, ax->rcount) < 0) {
Stephen Hemmingerddbe9a62009-01-09 13:01:40 +0000269 ax->dev->stats.rx_errors++;
Ralf Baechle5793f4b2005-10-14 14:28:09 +0100270 spin_unlock_bh(&ax->buflock);
271 return;
272 }
273 if (ax->crcmode != CRC_MODE_FLEX && ax->crcauto) {
274 printk(KERN_INFO
Ralf Baechle7b1401c2009-10-01 14:48:25 -0700275 "mkiss: %s: Switching to crc-flexnet\n",
Ralf Baechle5793f4b2005-10-14 14:28:09 +0100276 ax->dev->name);
277 ax->crcmode = CRC_MODE_FLEX;
278 }
279 ax->rcount -= 2;
280
281 /*
282 * dl9sau bugfix: the trailling two bytes flexnet crc
283 * will not be passed to the kernel. thus we have to
284 * correct the kissparm signature, because it indicates
285 * a crc but there's none
Ralf Baechle815f62b2005-08-24 18:06:36 +0100286 */
Ralf Baechle5793f4b2005-10-14 14:28:09 +0100287 *ax->rbuff &= ~0x20;
Ralf Baechle815f62b2005-08-24 18:06:36 +0100288 }
289 }
Ralf Baechle815f62b2005-08-24 18:06:36 +0100290
291 count = ax->rcount;
292
293 if ((skb = dev_alloc_skb(count)) == NULL) {
294 printk(KERN_ERR "mkiss: %s: memory squeeze, dropping packet.\n",
295 ax->dev->name);
Stephen Hemmingerddbe9a62009-01-09 13:01:40 +0000296 ax->dev->stats.rx_dropped++;
Jarek Poplawski9f30c762008-02-13 11:17:58 +0000297 spin_unlock_bh(&ax->buflock);
Ralf Baechle815f62b2005-08-24 18:06:36 +0100298 return;
299 }
300
Ralf Baechle815f62b2005-08-24 18:06:36 +0100301 memcpy(skb_put(skb,count), ax->rbuff, count);
Ralf Baechle815f62b2005-08-24 18:06:36 +0100302 skb->protocol = ax25_type_trans(skb, ax->dev);
303 netif_rx(skb);
Stephen Hemmingerddbe9a62009-01-09 13:01:40 +0000304 ax->dev->stats.rx_packets++;
305 ax->dev->stats.rx_bytes += count;
Jarek Poplawski9f30c762008-02-13 11:17:58 +0000306 spin_unlock_bh(&ax->buflock);
Ralf Baechle815f62b2005-08-24 18:06:36 +0100307}
308
309static void kiss_unesc(struct mkiss *ax, unsigned char s)
310{
311 switch (s) {
312 case END:
313 /* drop keeptest bit = VSV */
314 if (test_bit(AXF_KEEPTEST, &ax->flags))
315 clear_bit(AXF_KEEPTEST, &ax->flags);
316
317 if (!test_and_clear_bit(AXF_ERROR, &ax->flags) && (ax->rcount > 2))
318 ax_bump(ax);
319
320 clear_bit(AXF_ESCAPE, &ax->flags);
321 ax->rcount = 0;
322 return;
323
324 case ESC:
325 set_bit(AXF_ESCAPE, &ax->flags);
326 return;
327 case ESC_ESC:
328 if (test_and_clear_bit(AXF_ESCAPE, &ax->flags))
329 s = ESC;
330 break;
331 case ESC_END:
332 if (test_and_clear_bit(AXF_ESCAPE, &ax->flags))
333 s = END;
334 break;
335 }
336
337 spin_lock_bh(&ax->buflock);
338 if (!test_bit(AXF_ERROR, &ax->flags)) {
339 if (ax->rcount < ax->buffsize) {
340 ax->rbuff[ax->rcount++] = s;
341 spin_unlock_bh(&ax->buflock);
342 return;
343 }
344
Stephen Hemmingerddbe9a62009-01-09 13:01:40 +0000345 ax->dev->stats.rx_over_errors++;
Ralf Baechle815f62b2005-08-24 18:06:36 +0100346 set_bit(AXF_ERROR, &ax->flags);
347 }
348 spin_unlock_bh(&ax->buflock);
349}
350
351static int ax_set_mac_address(struct net_device *dev, void *addr)
352{
353 struct sockaddr_ax25 *sa = addr;
354
Herbert Xu932ff272006-06-09 12:20:56 -0700355 netif_tx_lock_bh(dev);
David S. Millere308a5d2008-07-15 00:13:44 -0700356 netif_addr_lock(dev);
Ralf Baechle815f62b2005-08-24 18:06:36 +0100357 memcpy(dev->dev_addr, &sa->sax25_call, AX25_ADDR_LEN);
David S. Millere308a5d2008-07-15 00:13:44 -0700358 netif_addr_unlock(dev);
Herbert Xu932ff272006-06-09 12:20:56 -0700359 netif_tx_unlock_bh(dev);
Ralf Baechle815f62b2005-08-24 18:06:36 +0100360
361 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362}
363
364/*---------------------------------------------------------------------------*/
365
Ralf Baechle815f62b2005-08-24 18:06:36 +0100366static void ax_changedmtu(struct mkiss *ax)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367{
368 struct net_device *dev = ax->dev;
369 unsigned char *xbuff, *rbuff, *oxbuff, *orbuff;
370 int len;
371
372 len = dev->mtu * 2;
373
374 /*
375 * allow for arrival of larger UDP packets, even if we say not to
376 * also fixes a bug in which SunOS sends 512-byte packets even with
377 * an MSS of 128
378 */
379 if (len < 576 * 2)
380 len = 576 * 2;
381
382 xbuff = kmalloc(len + 4, GFP_ATOMIC);
383 rbuff = kmalloc(len + 4, GFP_ATOMIC);
384
385 if (xbuff == NULL || rbuff == NULL) {
Ralf Baechle815f62b2005-08-24 18:06:36 +0100386 printk(KERN_ERR "mkiss: %s: unable to grow ax25 buffers, "
387 "MTU change cancelled.\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388 ax->dev->name);
389 dev->mtu = ax->mtu;
Jesper Juhlb4558ea2005-10-28 16:53:13 -0400390 kfree(xbuff);
391 kfree(rbuff);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392 return;
393 }
394
395 spin_lock_bh(&ax->buflock);
396
397 oxbuff = ax->xbuff;
398 ax->xbuff = xbuff;
399 orbuff = ax->rbuff;
400 ax->rbuff = rbuff;
401
402 if (ax->xleft) {
403 if (ax->xleft <= len) {
404 memcpy(ax->xbuff, ax->xhead, ax->xleft);
405 } else {
406 ax->xleft = 0;
Stephen Hemmingerddbe9a62009-01-09 13:01:40 +0000407 dev->stats.tx_dropped++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700408 }
409 }
410
411 ax->xhead = ax->xbuff;
412
413 if (ax->rcount) {
414 if (ax->rcount <= len) {
415 memcpy(ax->rbuff, orbuff, ax->rcount);
416 } else {
417 ax->rcount = 0;
Stephen Hemmingerddbe9a62009-01-09 13:01:40 +0000418 dev->stats.rx_over_errors++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419 set_bit(AXF_ERROR, &ax->flags);
420 }
421 }
422
423 ax->mtu = dev->mtu + 73;
424 ax->buffsize = len;
425
426 spin_unlock_bh(&ax->buflock);
427
Ralf Baechle815f62b2005-08-24 18:06:36 +0100428 kfree(oxbuff);
429 kfree(orbuff);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430}
431
432/* Encapsulate one AX.25 packet and stuff into a TTY queue. */
Ralf Baechle815f62b2005-08-24 18:06:36 +0100433static void ax_encaps(struct net_device *dev, unsigned char *icp, int len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434{
Ralf Baechle815f62b2005-08-24 18:06:36 +0100435 struct mkiss *ax = netdev_priv(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436 unsigned char *p;
437 int actual, count;
438
439 if (ax->mtu != ax->dev->mtu + 73) /* Someone has been ifconfigging */
440 ax_changedmtu(ax);
441
442 if (len > ax->mtu) { /* Sigh, shouldn't occur BUT ... */
443 len = ax->mtu;
444 printk(KERN_ERR "mkiss: %s: truncating oversized transmit packet!\n", ax->dev->name);
Stephen Hemmingerddbe9a62009-01-09 13:01:40 +0000445 dev->stats.tx_dropped++;
Ralf Baechle815f62b2005-08-24 18:06:36 +0100446 netif_start_queue(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700447 return;
448 }
449
450 p = icp;
451
452 spin_lock_bh(&ax->buflock);
Ralf Baechle5793f4b2005-10-14 14:28:09 +0100453 if ((*p & 0x0f) != 0) {
454 /* Configuration Command (kissparms(1).
455 * Protocol spec says: never append CRC.
456 * This fixes a very old bug in the linux
457 * kiss driver. -- dl9sau */
458 switch (*p & 0xff) {
459 case 0x85:
460 /* command from userspace especially for us,
461 * not for delivery to the tnc */
462 if (len > 1) {
463 int cmd = (p[1] & 0xff);
464 switch(cmd) {
465 case 3:
466 ax->crcmode = CRC_MODE_SMACK;
467 break;
468 case 2:
469 ax->crcmode = CRC_MODE_FLEX;
470 break;
471 case 1:
472 ax->crcmode = CRC_MODE_NONE;
473 break;
474 case 0:
475 default:
476 ax->crcmode = CRC_MODE_SMACK_TEST;
477 cmd = 0;
478 }
479 ax->crcauto = (cmd ? 0 : 1);
480 printk(KERN_INFO "mkiss: %s: crc mode %s %d\n", ax->dev->name, (len) ? "set to" : "is", cmd);
481 }
482 spin_unlock_bh(&ax->buflock);
483 netif_start_queue(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484
Ralf Baechle5793f4b2005-10-14 14:28:09 +0100485 return;
486 default:
Joe Perchesc2fd03a2012-06-04 12:44:18 +0000487 count = kiss_esc(p, ax->xbuff, len);
Ralf Baechle5793f4b2005-10-14 14:28:09 +0100488 }
489 } else {
490 unsigned short crc;
491 switch (ax->crcmode) {
492 case CRC_MODE_SMACK_TEST:
493 ax->crcmode = CRC_MODE_FLEX_TEST;
494 printk(KERN_INFO "mkiss: %s: Trying crc-smack\n", ax->dev->name);
495 // fall through
496 case CRC_MODE_SMACK:
497 *p |= 0x80;
498 crc = swab16(crc16(0, p, len));
Joe Perchesc2fd03a2012-06-04 12:44:18 +0000499 count = kiss_esc_crc(p, ax->xbuff, crc, len+2);
Ralf Baechle5793f4b2005-10-14 14:28:09 +0100500 break;
501 case CRC_MODE_FLEX_TEST:
502 ax->crcmode = CRC_MODE_NONE;
503 printk(KERN_INFO "mkiss: %s: Trying crc-flexnet\n", ax->dev->name);
504 // fall through
505 case CRC_MODE_FLEX:
506 *p |= 0x20;
507 crc = calc_crc_flex(p, len);
Joe Perchesc2fd03a2012-06-04 12:44:18 +0000508 count = kiss_esc_crc(p, ax->xbuff, crc, len+2);
Ralf Baechle5793f4b2005-10-14 14:28:09 +0100509 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510
Ralf Baechle5793f4b2005-10-14 14:28:09 +0100511 default:
Joe Perchesc2fd03a2012-06-04 12:44:18 +0000512 count = kiss_esc(p, ax->xbuff, len);
Ralf Baechle5793f4b2005-10-14 14:28:09 +0100513 }
514 }
Ralf Baechlec1854eb2006-01-08 22:31:04 -0800515 spin_unlock_bh(&ax->buflock);
Ralf Baechle5793f4b2005-10-14 14:28:09 +0100516
Ralf Baechle815f62b2005-08-24 18:06:36 +0100517 set_bit(TTY_DO_WRITE_WAKEUP, &ax->tty->flags);
Alan Coxf34d7a52008-04-30 00:54:13 -0700518 actual = ax->tty->ops->write(ax->tty, ax->xbuff, count);
Stephen Hemmingerddbe9a62009-01-09 13:01:40 +0000519 dev->stats.tx_packets++;
520 dev->stats.tx_bytes += actual;
Ralf Baechle815f62b2005-08-24 18:06:36 +0100521
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522 ax->dev->trans_start = jiffies;
523 ax->xleft = count - actual;
524 ax->xhead = ax->xbuff + actual;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700525}
526
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527/* Encapsulate an AX.25 packet and kick it into a TTY queue. */
Stephen Hemminger36e4d642009-08-31 19:50:43 +0000528static netdev_tx_t ax_xmit(struct sk_buff *skb, struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529{
Ralf Baechle815f62b2005-08-24 18:06:36 +0100530 struct mkiss *ax = netdev_priv(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531
532 if (!netif_running(dev)) {
533 printk(KERN_ERR "mkiss: %s: xmit call when iface is down\n", dev->name);
Patrick McHardy5b548142009-06-12 06:22:29 +0000534 return NETDEV_TX_BUSY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700535 }
536
537 if (netif_queue_stopped(dev)) {
538 /*
539 * May be we must check transmitter timeout here ?
540 * 14 Oct 1994 Dmitry Gorodchanin.
541 */
Marcelo Feitoza Parisicd8749b2005-07-15 11:16:42 +0100542 if (time_before(jiffies, dev->trans_start + 20 * HZ)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700543 /* 20 sec timeout not reached */
Patrick McHardy5b548142009-06-12 06:22:29 +0000544 return NETDEV_TX_BUSY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700545 }
546
547 printk(KERN_ERR "mkiss: %s: transmit timed out, %s?\n", dev->name,
Eugene Teo56087842008-07-30 12:38:59 -0700548 (tty_chars_in_buffer(ax->tty) || ax->xleft) ?
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549 "bad line quality" : "driver error");
550
551 ax->xleft = 0;
Ralf Baechle815f62b2005-08-24 18:06:36 +0100552 clear_bit(TTY_DO_WRITE_WAKEUP, &ax->tty->flags);
553 netif_start_queue(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554 }
555
556 /* We were not busy, so we are now... :-) */
557 if (skb != NULL) {
Ralf Baechle815f62b2005-08-24 18:06:36 +0100558 netif_stop_queue(dev);
559 ax_encaps(dev, skb->data, skb->len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560 kfree_skb(skb);
561 }
562
Patrick McHardy6ed10652009-06-23 06:03:08 +0000563 return NETDEV_TX_OK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564}
565
Ralf Baechle815f62b2005-08-24 18:06:36 +0100566static int ax_open_dev(struct net_device *dev)
567{
568 struct mkiss *ax = netdev_priv(dev);
569
570 if (ax->tty == NULL)
571 return -ENODEV;
572
573 return 0;
574}
575
Linus Torvalds1da177e2005-04-16 15:20:36 -0700576/* Open the low-level part of the AX25 channel. Easy! */
577static int ax_open(struct net_device *dev)
578{
Ralf Baechle815f62b2005-08-24 18:06:36 +0100579 struct mkiss *ax = netdev_priv(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700580 unsigned long len;
581
582 if (ax->tty == NULL)
583 return -ENODEV;
584
585 /*
586 * Allocate the frame buffers:
587 *
588 * rbuff Receive buffer.
589 * xbuff Transmit buffer.
590 */
591 len = dev->mtu * 2;
592
593 /*
594 * allow for arrival of larger UDP packets, even if we say not to
595 * also fixes a bug in which SunOS sends 512-byte packets even with
596 * an MSS of 128
597 */
598 if (len < 576 * 2)
599 len = 576 * 2;
600
601 if ((ax->rbuff = kmalloc(len + 4, GFP_KERNEL)) == NULL)
602 goto norbuff;
603
604 if ((ax->xbuff = kmalloc(len + 4, GFP_KERNEL)) == NULL)
605 goto noxbuff;
606
607 ax->mtu = dev->mtu + 73;
608 ax->buffsize = len;
609 ax->rcount = 0;
610 ax->xleft = 0;
611
612 ax->flags &= (1 << AXF_INUSE); /* Clear ESCAPE & ERROR flags */
613
614 spin_lock_init(&ax->buflock);
615
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616 return 0;
617
618noxbuff:
619 kfree(ax->rbuff);
620
621norbuff:
622 return -ENOMEM;
623}
624
625
626/* Close the low-level part of the AX25 channel. Easy! */
627static int ax_close(struct net_device *dev)
628{
Ralf Baechle815f62b2005-08-24 18:06:36 +0100629 struct mkiss *ax = netdev_priv(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630
Ralf Baechle815f62b2005-08-24 18:06:36 +0100631 if (ax->tty)
632 clear_bit(TTY_DO_WRITE_WAKEUP, &ax->tty->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633
634 netif_stop_queue(dev);
635
636 return 0;
637}
638
Stephen Hemminger6095e082009-01-09 13:01:41 +0000639static const struct net_device_ops ax_netdev_ops = {
640 .ndo_open = ax_open_dev,
641 .ndo_stop = ax_close,
642 .ndo_start_xmit = ax_xmit,
643 .ndo_set_mac_address = ax_set_mac_address,
Eric W. Biederman3b6a94b2015-03-02 00:05:28 -0600644 .ndo_neigh_construct = ax25_neigh_construct,
Stephen Hemminger6095e082009-01-09 13:01:41 +0000645};
646
Ralf Baechle815f62b2005-08-24 18:06:36 +0100647static void ax_setup(struct net_device *dev)
648{
Ralf Baechle815f62b2005-08-24 18:06:36 +0100649 /* Finish setting up the DEVICE info. */
650 dev->mtu = AX_MTU;
Ralf Baechle815f62b2005-08-24 18:06:36 +0100651 dev->hard_header_len = 0;
652 dev->addr_len = 0;
653 dev->type = ARPHRD_AX25;
Eric W. Biederman3b6a94b2015-03-02 00:05:28 -0600654 dev->neigh_priv_len = sizeof(struct ax25_neigh_priv);
Ralf Baechle815f62b2005-08-24 18:06:36 +0100655 dev->tx_queue_len = 10;
Eric W. Biederman56fc7e72015-03-02 00:03:02 -0600656 dev->header_ops = &ax25_header_ops;
Stephen Hemminger6095e082009-01-09 13:01:41 +0000657 dev->netdev_ops = &ax_netdev_ops;
Stephen Hemminger3b04ddd2007-10-09 01:40:57 -0700658
Ralf Baechle815f62b2005-08-24 18:06:36 +0100659
Ralf Baechle15b1c0e2006-12-07 15:47:08 -0800660 memcpy(dev->broadcast, &ax25_bcast, AX25_ADDR_LEN);
661 memcpy(dev->dev_addr, &ax25_defaddr, AX25_ADDR_LEN);
Ralf Baechle815f62b2005-08-24 18:06:36 +0100662
663 dev->flags = IFF_BROADCAST | IFF_MULTICAST;
664}
665
666/*
667 * We have a potential race on dereferencing tty->disc_data, because the tty
668 * layer provides no locking at all - thus one cpu could be running
669 * sixpack_receive_buf while another calls sixpack_close, which zeroes
670 * tty->disc_data and frees the memory that sixpack_receive_buf is using. The
671 * best way to fix this is to use a rwlock in the tty struct, but for now we
672 * use a single global rwlock for all ttys in ppp line discipline.
673 */
Ralf Baechled5919582005-10-04 12:22:16 +0100674static DEFINE_RWLOCK(disc_data_lock);
Ralf Baechle815f62b2005-08-24 18:06:36 +0100675
676static struct mkiss *mkiss_get(struct tty_struct *tty)
677{
678 struct mkiss *ax;
679
680 read_lock(&disc_data_lock);
681 ax = tty->disc_data;
682 if (ax)
683 atomic_inc(&ax->refcnt);
684 read_unlock(&disc_data_lock);
685
686 return ax;
687}
688
689static void mkiss_put(struct mkiss *ax)
690{
691 if (atomic_dec_and_test(&ax->refcnt))
692 up(&ax->dead_sem);
693}
694
Ralf Baechle5793f4b2005-10-14 14:28:09 +0100695static int crc_force = 0; /* Can be overridden with insmod */
696
Ralf Baechle815f62b2005-08-24 18:06:36 +0100697static int mkiss_open(struct tty_struct *tty)
698{
699 struct net_device *dev;
700 struct mkiss *ax;
701 int err;
702
703 if (!capable(CAP_NET_ADMIN))
704 return -EPERM;
Alan Coxf34d7a52008-04-30 00:54:13 -0700705 if (tty->ops->write == NULL)
706 return -EOPNOTSUPP;
Ralf Baechle815f62b2005-08-24 18:06:36 +0100707
Tom Gundersenc835a672014-07-14 16:37:24 +0200708 dev = alloc_netdev(sizeof(struct mkiss), "ax%d", NET_NAME_UNKNOWN,
709 ax_setup);
Ralf Baechle815f62b2005-08-24 18:06:36 +0100710 if (!dev) {
711 err = -ENOMEM;
712 goto out;
713 }
714
715 ax = netdev_priv(dev);
716 ax->dev = dev;
717
718 spin_lock_init(&ax->buflock);
719 atomic_set(&ax->refcnt, 1);
Thomas Gleixner495e64b2010-09-07 14:32:18 +0000720 sema_init(&ax->dead_sem, 0);
Ralf Baechle815f62b2005-08-24 18:06:36 +0100721
722 ax->tty = tty;
723 tty->disc_data = ax;
Alan Cox33f0f882006-01-09 20:54:13 -0800724 tty->receive_room = 65535;
Ralf Baechle815f62b2005-08-24 18:06:36 +0100725
Alan Coxf34d7a52008-04-30 00:54:13 -0700726 tty_driver_flush_buffer(tty);
Ralf Baechle815f62b2005-08-24 18:06:36 +0100727
728 /* Restore default settings */
729 dev->type = ARPHRD_AX25;
730
731 /* Perform the low-level AX25 initialization. */
732 if ((err = ax_open(ax->dev))) {
733 goto out_free_netdev;
734 }
735
736 if (register_netdev(dev))
737 goto out_free_buffers;
738
Ralf Baechle5793f4b2005-10-14 14:28:09 +0100739 /* after register_netdev() - because else printk smashes the kernel */
740 switch (crc_force) {
741 case 3:
742 ax->crcmode = CRC_MODE_SMACK;
743 printk(KERN_INFO "mkiss: %s: crc mode smack forced.\n",
744 ax->dev->name);
745 break;
746 case 2:
747 ax->crcmode = CRC_MODE_FLEX;
748 printk(KERN_INFO "mkiss: %s: crc mode flexnet forced.\n",
749 ax->dev->name);
750 break;
751 case 1:
752 ax->crcmode = CRC_MODE_NONE;
753 printk(KERN_INFO "mkiss: %s: crc mode disabled.\n",
754 ax->dev->name);
755 break;
756 case 0:
757 /* fall through */
758 default:
759 crc_force = 0;
760 printk(KERN_INFO "mkiss: %s: crc mode is auto.\n",
761 ax->dev->name);
762 ax->crcmode = CRC_MODE_SMACK_TEST;
763 }
764 ax->crcauto = (crc_force ? 0 : 1);
765
Ralf Baechle815f62b2005-08-24 18:06:36 +0100766 netif_start_queue(dev);
767
768 /* Done. We have linked the TTY line to a channel. */
769 return 0;
770
771out_free_buffers:
772 kfree(ax->rbuff);
773 kfree(ax->xbuff);
774
775out_free_netdev:
776 free_netdev(dev);
777
778out:
779 return err;
780}
781
782static void mkiss_close(struct tty_struct *tty)
783{
784 struct mkiss *ax;
785
Arnd Bergmann6e4e2f82011-07-01 17:30:00 -0700786 write_lock_bh(&disc_data_lock);
Ralf Baechle815f62b2005-08-24 18:06:36 +0100787 ax = tty->disc_data;
788 tty->disc_data = NULL;
Arnd Bergmann6e4e2f82011-07-01 17:30:00 -0700789 write_unlock_bh(&disc_data_lock);
Ralf Baechle815f62b2005-08-24 18:06:36 +0100790
Al Viro79ea13c2008-01-24 02:06:46 -0800791 if (!ax)
Ralf Baechle815f62b2005-08-24 18:06:36 +0100792 return;
793
794 /*
795 * We have now ensured that nobody can start using ap from now on, but
796 * we have to wait for all existing users to finish.
797 */
798 if (!atomic_dec_and_test(&ax->refcnt))
799 down(&ax->dead_sem);
800
801 unregister_netdev(ax->dev);
802
803 /* Free all AX25 frame buffers. */
804 kfree(ax->rbuff);
805 kfree(ax->xbuff);
806
807 ax->tty = NULL;
808}
809
810/* Perform I/O control on an active ax25 channel. */
811static int mkiss_ioctl(struct tty_struct *tty, struct file *file,
812 unsigned int cmd, unsigned long arg)
813{
814 struct mkiss *ax = mkiss_get(tty);
Julia Lawallf40e0632008-12-16 15:43:29 -0800815 struct net_device *dev;
Ralf Baechle815f62b2005-08-24 18:06:36 +0100816 unsigned int tmp, err;
817
818 /* First make sure we're connected. */
819 if (ax == NULL)
820 return -ENXIO;
Julia Lawallf40e0632008-12-16 15:43:29 -0800821 dev = ax->dev;
Ralf Baechle815f62b2005-08-24 18:06:36 +0100822
823 switch (cmd) {
824 case SIOCGIFNAME:
825 err = copy_to_user((void __user *) arg, ax->dev->name,
826 strlen(ax->dev->name) + 1) ? -EFAULT : 0;
827 break;
828
829 case SIOCGIFENCAP:
830 err = put_user(4, (int __user *) arg);
831 break;
832
833 case SIOCSIFENCAP:
834 if (get_user(tmp, (int __user *) arg)) {
835 err = -EFAULT;
836 break;
837 }
838
839 ax->mode = tmp;
840 dev->addr_len = AX25_ADDR_LEN;
841 dev->hard_header_len = AX25_KISS_HEADER_LEN +
842 AX25_MAX_HEADER_LEN + 3;
843 dev->type = ARPHRD_AX25;
844
845 err = 0;
846 break;
847
848 case SIOCSIFHWADDR: {
849 char addr[AX25_ADDR_LEN];
Ralf Baechle815f62b2005-08-24 18:06:36 +0100850
851 if (copy_from_user(&addr,
852 (void __user *) arg, AX25_ADDR_LEN)) {
853 err = -EFAULT;
854 break;
855 }
856
Herbert Xu932ff272006-06-09 12:20:56 -0700857 netif_tx_lock_bh(dev);
Ralf Baechle815f62b2005-08-24 18:06:36 +0100858 memcpy(dev->dev_addr, addr, AX25_ADDR_LEN);
Herbert Xu932ff272006-06-09 12:20:56 -0700859 netif_tx_unlock_bh(dev);
Ralf Baechle815f62b2005-08-24 18:06:36 +0100860
861 err = 0;
862 break;
863 }
864 default:
865 err = -ENOIOCTLCMD;
866 }
867
868 mkiss_put(ax);
869
870 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700871}
872
Arnd Bergmann9646e7c2009-11-06 22:51:16 -0800873#ifdef CONFIG_COMPAT
874static long mkiss_compat_ioctl(struct tty_struct *tty, struct file *file,
875 unsigned int cmd, unsigned long arg)
876{
Arnd Bergmann07c3c4e2009-11-15 21:13:21 -0800877 switch (cmd) {
Arnd Bergmann9646e7c2009-11-06 22:51:16 -0800878 case SIOCGIFNAME:
879 case SIOCGIFENCAP:
880 case SIOCSIFENCAP:
881 case SIOCSIFHWADDR:
882 return mkiss_ioctl(tty, file, cmd,
883 (unsigned long)compat_ptr(arg));
884 }
885
886 return -ENOIOCTLCMD;
887}
888#endif
889
Linus Torvalds1da177e2005-04-16 15:20:36 -0700890/*
891 * Handle the 'receiver data ready' interrupt.
892 * This function is called by the 'tty_io' module in the kernel when
893 * a block of data has been received, which can now be decapsulated
894 * and sent on to the AX.25 layer for further processing.
895 */
Linus Torvalds55db4c62011-06-04 06:33:24 +0900896static void mkiss_receive_buf(struct tty_struct *tty, const unsigned char *cp,
897 char *fp, int count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700898{
Ralf Baechle815f62b2005-08-24 18:06:36 +0100899 struct mkiss *ax = mkiss_get(tty);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700900
Ralf Baechle815f62b2005-08-24 18:06:36 +0100901 if (!ax)
Linus Torvalds55db4c62011-06-04 06:33:24 +0900902 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700903
904 /*
905 * Argh! mtu change time! - costs us the packet part received
906 * at the change
907 */
908 if (ax->mtu != ax->dev->mtu + 73)
909 ax_changedmtu(ax);
910
911 /* Read the characters out of the buffer */
Linus Torvalds55db4c62011-06-04 06:33:24 +0900912 while (count--) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700913 if (fp != NULL && *fp++) {
914 if (!test_and_set_bit(AXF_ERROR, &ax->flags))
Stephen Hemmingerddbe9a62009-01-09 13:01:40 +0000915 ax->dev->stats.rx_errors++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916 cp++;
917 continue;
918 }
919
920 kiss_unesc(ax, *cp++);
921 }
Ralf Baechle815f62b2005-08-24 18:06:36 +0100922
923 mkiss_put(ax);
Alan Cox39c2e602008-04-30 00:54:18 -0700924 tty_unthrottle(tty);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700925}
926
Linus Torvalds1da177e2005-04-16 15:20:36 -0700927/*
Ralf Baechle815f62b2005-08-24 18:06:36 +0100928 * Called by the driver when there's room for more data. If we have
929 * more packets to send, we send them here.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700930 */
Ralf Baechle815f62b2005-08-24 18:06:36 +0100931static void mkiss_write_wakeup(struct tty_struct *tty)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700932{
Ralf Baechle815f62b2005-08-24 18:06:36 +0100933 struct mkiss *ax = mkiss_get(tty);
934 int actual;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700935
Ralf Baechle815f62b2005-08-24 18:06:36 +0100936 if (!ax)
937 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700938
Ralf Baechle815f62b2005-08-24 18:06:36 +0100939 if (ax->xleft <= 0) {
940 /* Now serial buffer is almost free & we can start
941 * transmission of another packet
942 */
943 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700944
Ralf Baechle815f62b2005-08-24 18:06:36 +0100945 netif_wake_queue(ax->dev);
946 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700947 }
948
Alan Coxf34d7a52008-04-30 00:54:13 -0700949 actual = tty->ops->write(tty, ax->xhead, ax->xleft);
Ralf Baechle815f62b2005-08-24 18:06:36 +0100950 ax->xleft -= actual;
951 ax->xhead += actual;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700952
Ralf Baechle815f62b2005-08-24 18:06:36 +0100953out:
954 mkiss_put(ax);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700955}
956
Alan Coxa352def2008-07-16 21:53:12 +0100957static struct tty_ldisc_ops ax_ldisc = {
Ralf Baechle74cfe032005-10-12 23:11:01 +0100958 .owner = THIS_MODULE,
Ralf Baechle815f62b2005-08-24 18:06:36 +0100959 .magic = TTY_LDISC_MAGIC,
960 .name = "mkiss",
961 .open = mkiss_open,
962 .close = mkiss_close,
963 .ioctl = mkiss_ioctl,
Arnd Bergmann9646e7c2009-11-06 22:51:16 -0800964#ifdef CONFIG_COMPAT
965 .compat_ioctl = mkiss_compat_ioctl,
966#endif
Ralf Baechle815f62b2005-08-24 18:06:36 +0100967 .receive_buf = mkiss_receive_buf,
Ralf Baechle815f62b2005-08-24 18:06:36 +0100968 .write_wakeup = mkiss_write_wakeup
969};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700970
Andi Kleenafa8c782012-10-04 17:11:58 -0700971static const char banner[] __initconst = KERN_INFO \
Ralf Baechle815f62b2005-08-24 18:06:36 +0100972 "mkiss: AX.25 Multikiss, Hans Albas PE1AYX\n";
Andi Kleenafa8c782012-10-04 17:11:58 -0700973static const char msg_regfail[] __initconst = KERN_ERR \
Ralf Baechle815f62b2005-08-24 18:06:36 +0100974 "mkiss: can't register line discipline (err = %d)\n";
Linus Torvalds1da177e2005-04-16 15:20:36 -0700975
976static int __init mkiss_init_driver(void)
977{
978 int status;
979
980 printk(banner);
981
Hannes Edereb33ae22009-02-14 11:33:21 +0000982 status = tty_register_ldisc(N_AX25, &ax_ldisc);
983 if (status != 0)
984 printk(msg_regfail, status);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700985
Linus Torvalds1da177e2005-04-16 15:20:36 -0700986 return status;
987}
988
Andi Kleenafa8c782012-10-04 17:11:58 -0700989static const char msg_unregfail[] = KERN_ERR \
Ralf Baechle815f62b2005-08-24 18:06:36 +0100990 "mkiss: can't unregister line discipline (err = %d)\n";
991
Linus Torvalds1da177e2005-04-16 15:20:36 -0700992static void __exit mkiss_exit_driver(void)
993{
Ralf Baechle815f62b2005-08-24 18:06:36 +0100994 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700995
Ralf Baechle815f62b2005-08-24 18:06:36 +0100996 if ((ret = tty_unregister_ldisc(N_AX25)))
997 printk(msg_unregfail, ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700998}
999
Ralf Baechle815f62b2005-08-24 18:06:36 +01001000MODULE_AUTHOR("Ralf Baechle DL5RB <ralf@linux-mips.org>");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001001MODULE_DESCRIPTION("KISS driver for AX.25 over TTYs");
Rusty Russell8d3b33f2006-03-25 03:07:05 -08001002module_param(crc_force, int, 0);
Ralf Baechle5793f4b2005-10-14 14:28:09 +01001003MODULE_PARM_DESC(crc_force, "crc [0 = auto | 1 = none | 2 = flexnet | 3 = smack]");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001004MODULE_LICENSE("GPL");
1005MODULE_ALIAS_LDISC(N_AX25);
Ralf Baechle815f62b2005-08-24 18:06:36 +01001006
Linus Torvalds1da177e2005-04-16 15:20:36 -07001007module_init(mkiss_init_driver);
1008module_exit(mkiss_exit_driver);