Initial import from FreeBSD RELENG_4:
[dragonfly.git] / sys / netgraph / ng_device.c
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984263bc
MD
1/*
2 * Copyright (c) 2002 Mark Santcroos <marks@ripe.net>
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 * 3. The name of the author may not be used to endorse or promote products
13 * derived from this software without specific prior written permission.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 *
26 * Netgraph "device" node
27 *
28 * This node presents a /dev/ngd%d device that interfaces to an other
29 * netgraph node.
30 *
31 * $FreeBSD: src/sys/netgraph/ng_device.c,v 1.1.2.1 2002/08/23 07:15:44 julian Exp $
32 *
33 */
34
35#include <sys/param.h>
36#include <sys/systm.h>
37#include <sys/kernel.h>
38#include <sys/mbuf.h>
39#include <sys/uio.h>
40#include <sys/queue.h>
41#include <sys/malloc.h>
42#include <sys/conf.h>
43#include <sys/poll.h>
44#include <sys/ioccom.h>
45
46#include <netgraph/ng_message.h>
47#include <netgraph/netgraph.h>
48
49#include "ng_device.h"
50
51/* turn this on for verbose messages */
52#define NGD_DEBUG
53
54/* Netgraph methods */
55static ng_constructor_t ng_device_cons;
56static ng_rcvmsg_t ng_device_rcvmsg;
57static ng_newhook_t ng_device_newhook;
58static ng_connect_t ng_device_connect;
59static ng_rcvdata_t ng_device_rcvdata;
60static ng_disconnect_t ng_device_disconnect;
61static int ng_device_mod_event(module_t mod, int event, void *data);
62
63static int ng_device_init(void);
64static int get_free_unit(void);
65
66/* Netgraph type */
67static struct ng_type typestruct = {
68 NG_VERSION, /* version */
69 NG_DEVICE_NODE_TYPE, /* name */
70 ng_device_mod_event, /* modevent */
71 ng_device_cons, /* constructor */
72 ng_device_rcvmsg, /* receive msg */
73 NULL, /* shutdown */
74 ng_device_newhook, /* newhook */
75 NULL, /* findhook */
76 ng_device_connect, /* connect */
77 ng_device_rcvdata, /* receive data */
78 ng_device_rcvdata, /* receive queued data */
79 ng_device_disconnect, /* disconnect */
80 NULL
81};
82NETGRAPH_INIT(device, &typestruct);
83
84/* per hook data */
85struct ngd_connection {
86 SLIST_ENTRY(ngd_connection) links;
87
88 dev_t ngddev;
89 struct ng_hook *active_hook;
90 char *readq;
91 int loc;
92 int unit;
93};
94
95/* global data */
96struct ngd_softc {
97 SLIST_HEAD(, ngd_connection) head;
98
99 node_p node;
100 char nodename[NG_NODELEN + 1];
101} ngd_softc;
102
103/* helper definition */
104#define MIN(a, b) ((a) < (b) ? (a) : (b))
105
106/* the per connection receiving queue maximum */
107#define NGD_QUEUE_SIZE (1024*10)
108
109/* Maximum number of NGD devices */
110#define MAX_NGD 25 /* should be more than enough for now */
111
112static d_close_t ngdclose;
113static d_open_t ngdopen;
114static d_read_t ngdread;
115static d_write_t ngdwrite;
116static d_ioctl_t ngdioctl;
117static d_poll_t ngdpoll;
118
119#define NGD_CDEV_MAJOR 20
120static struct cdevsw ngd_cdevsw = {
121 /* open */ ngdopen,
122 /* close */ ngdclose,
123 /* read */ ngdread,
124 /* write */ ngdwrite,
125 /* ioctl */ ngdioctl,
126 /* poll */ ngdpoll,
127 /* mmap */ nommap,
128 /* strategy */ nostrategy,
129 /* name */ "ngd",
130 /* maj */ NGD_CDEV_MAJOR,
131 /* dump */ nodump,
132 /* psize */ nopsize,
133 /* flags */ 0,
134 /* bmaj */ -1
135};
136
137/*
138 * this holds all the stuff that should be done at load time
139 */
140static int
141ng_device_mod_event(module_t mod, int event, void *data)
142{
143 int error = 0;
144
145#ifdef NGD_DEBUG
146 printf("%s()\n", __func__);
147#endif /* NGD_DEBUG */
148
149 switch (event) {
150 case MOD_LOAD:
151 ng_device_init();
152 break;
153
154 case MOD_UNLOAD:
155 /* XXX do we need to do something specific ? */
156 /* ng_device_breakdown */
157 /* cdevsw_remove(&ngd_cdevsw);*/
158 error = EBUSY; /* no unload! */
159 break;
160
161
162 default:
163 error = EOPNOTSUPP;
164 break;
165 }
166
167 return(error);
168}
169
170
171static int
172ng_device_init()
173{
174 struct ngd_softc *sc = &ngd_softc;
175
176#ifdef NGD_DEBUG
177 printf("%s()\n", __func__);
178#endif /* NGD_DEBUG */
179
180 SLIST_INIT(&sc->head);
181
182 if (ng_make_node_common(&typestruct, &sc->node) != 0) {
183 printf("%s(): ng_make_node_common failed\n", __func__);
184 return(ENXIO);
185 }
186 sprintf(sc->nodename, "%s", NG_DEVICE_NODE_TYPE);
187 if (ng_name_node(sc->node, sc->nodename)) {
188 NG_NODE_UNREF(sc->node); /* make it go away again */
189 printf("%s(): ng_name_node failed\n", __func__);
190 return(ENXIO);
191 }
192 NG_NODE_SET_PRIVATE(sc->node, sc);
193 cdevsw_add(&ngd_cdevsw);
194
195 return(0);
196}
197
198/*
199 * don't allow to be created, only the device can do that
200 */
201static int
202ng_device_cons(node_p node)
203{
204
205#ifdef NGD_DEBUG
206 printf("%s()\n", __func__);
207#endif /* NGD_DEBUG */
208
209 return(EINVAL);
210}
211
212/*
213 * Receive control message. We just free it.
214 */
215static int
216ng_device_rcvmsg(node_p node,
217 struct ng_mesg *msg, const char *retaddr, struct ng_mesg **rptr)
218{
219 FREE(msg, M_NETGRAPH);
220 return(ENOTTY);
221}
222
223static int
224get_free_unit()
225{
226 struct ngd_connection *tmp = NULL;
227 struct ngd_softc *sc = &ngd_softc;
228 int n = 0;
229 int unit = -1;
230
231#ifdef NGD_DEBUG
232 printf("%s()\n", __func__);
233#endif /* NGD_DEBUG */
234
235 /* When there is no list yet, the first device unit is always 0. */
236 if SLIST_EMPTY(&sc->head) {
237 unit = 0;
238 return(unit);
239 }
240
241 /* Just do a brute force loop to find the first free unit that is
242 * smaller than MAX_NGD.
243 * Set MAX_NGD to a large value, doesn't impact performance.
244 */
245 for(n = 0;n<MAX_NGD && unit == -1;n++) {
246 SLIST_FOREACH(tmp, &sc->head, links) {
247
248 if(tmp->unit == n) {
249 unit = -1;
250 break;
251 }
252 unit = n;
253 }
254 }
255
256 return(unit);
257}
258
259/*
260 * incoming hook
261 */
262static int
263ng_device_newhook(node_p node, hook_p hook, const char *name)
264{
265 struct ngd_softc *sc = &ngd_softc;
266 struct ngd_connection * new_connection = NULL;
267
268#ifdef NGD_DEBUG
269 printf("%s()\n", __func__);
270#endif /* NGD_DEBUG */
271
272 new_connection = malloc(sizeof(struct ngd_connection), M_DEVBUF, M_NOWAIT);
273 if(new_connection == NULL) {
274 printf("%s(): ERROR: new_connection == NULL\n", __func__);
275 return(-1);
276 }
277
278 new_connection->unit = get_free_unit();
279 if(new_connection->unit<0) {
280 printf("%s: No free unit found by get_free_unit(), "
281 "increas MAX_NGD\n", __func__);
282 free(new_connection, M_DEVBUF);
283 return(-1);
284 }
285 new_connection->ngddev = make_dev(&ngd_cdevsw,
286 new_connection->unit, 0, 0, 0600, "ngd%d", new_connection->unit);
287 if(new_connection->ngddev == NULL) {
288 printf("%s(): make_dev failed\n", __func__);
289 SLIST_REMOVE(&sc->head, new_connection, ngd_connection, links);
290 free(new_connection, M_DEVBUF);
291 return(-1);
292 }
293
294 new_connection->readq =
295 malloc(sizeof(char)*NGD_QUEUE_SIZE, M_DEVBUF, M_NOWAIT | M_ZERO);
296 if(new_connection->readq == NULL) {
297 printf("%s(): readq malloc failed\n", __func__);
298 destroy_dev(new_connection->ngddev);
299 SLIST_REMOVE(&sc->head, new_connection, ngd_connection, links);
300 free(new_connection, M_DEVBUF);
301 return(-1);
302 }
303
304 /* point to begin of buffer */
305 new_connection->loc = 0;
306 new_connection->active_hook = hook;
307
308 SLIST_INSERT_HEAD(&sc->head, new_connection, links);
309
310 return(0);
311}
312
313/*
314 * we gave ok to a new hook
315 * now connect
316 */
317static int
318ng_device_connect(hook_p hook)
319{
320
321#ifdef NGD_DEBUG
322 printf("%s()\n", __func__);
323#endif /* NGD_DEBUG */
324
325 return(0);
326}
327
328
329/*
330 * Receive data from hook
331 */
332static int
333ng_device_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
334{
335 struct ngd_softc *sc = &ngd_softc;
336 struct ngd_connection * connection = NULL;
337 struct ngd_connection * tmp;
338 char *buffer;
339
340#ifdef NGD_DEBUG
341 printf("%s()\n", __func__);
342#endif /* NGD_DEBUG */
343
344 SLIST_FOREACH(tmp, &sc->head, links) {
345 if(tmp->active_hook == hook) {
346 connection = tmp;
347 }
348 }
349 if(connection == NULL) {
350 printf("%s(): connection still NULL, no hook found\n", __func__);
351 return(-1);
352 }
353
354 NG_FREE_META(meta);
355
356 m = m_pullup(m, m->m_len);
357 if(m == NULL) {
358 printf("%s(): ERROR: m_pullup failed\n", __func__);
359 return(-1);
360 }
361
362 buffer = malloc(sizeof(char)*m->m_len, M_DEVBUF, M_NOWAIT | M_ZERO);
363 if(buffer == NULL) {
364 printf("%s(): ERROR: buffer malloc failed\n", __func__);
365 return(-1);
366 }
367
368 buffer = mtod(m, char *);
369
370 if( (connection->loc+m->m_len) < NGD_QUEUE_SIZE) {
371 memcpy(connection->readq+connection->loc, buffer, m->m_len);
372 connection->loc += m->m_len;
373 } else
374 printf("%s(): queue full, first read out a bit\n", __func__);
375
376 free(buffer, M_DEVBUF);
377
378 return(0);
379}
380
381/*
382 * Removal of the last link destroys the node
383 */
384static int
385ng_device_disconnect(hook_p hook)
386{
387 struct ngd_softc *sc = &ngd_softc;
388 struct ngd_connection * connection = NULL;
389 struct ngd_connection * tmp;
390
391#ifdef NGD_DEBUG
392 printf("%s()\n", __func__);
393#endif /* NGD_DEBUG */
394
395 SLIST_FOREACH(tmp, &sc->head, links) {
396 if(tmp->active_hook == hook) {
397 connection = tmp;
398 }
399 }
400 if(connection == NULL) {
401 printf("%s(): connection still NULL, no hook found\n",
402 __func__);
403 return(-1);
404 }
405
406 free(connection->readq, M_DEVBUF);
407
408 destroy_dev(connection->ngddev);
409
410 SLIST_REMOVE(&sc->head, connection, ngd_connection, links);
411
412 return(0);
413}
414/*
415 * the device is opened
416 */
417static int
418ngdopen(dev_t dev, int flag, int mode, struct thread *td)
419{
420
421#ifdef NGD_DEBUG
422 printf("%s()\n", __func__);
423#endif /* NGD_DEBUG */
424
425 return(0);
426}
427
428/*
429 * the device is closed
430 */
431static int
432ngdclose(dev_t dev, int flag, int mode, struct thread *td)
433{
434
435#ifdef NGD_DEBUG
436 printf("%s()\n", __func__);
437#endif
438
439 return(0);
440}
441
442
443/*
444 * process ioctl
445 *
446 * they are translated into netgraph messages and passed on
447 *
448 */
449static int
450ngdioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct thread *td)
451{
452 struct ngd_softc *sc = &ngd_softc;
453 struct ngd_connection * connection = NULL;
454 struct ngd_connection * tmp;
455 int error = 0;
456 struct ng_mesg *msg;
457 struct ngd_param_s * datap;
458
459#ifdef NGD_DEBUG
460 printf("%s()\n", __func__);
461#endif /* NGD_DEBUG */
462
463 SLIST_FOREACH(tmp, &sc->head, links) {
464 if(tmp->ngddev == dev) {
465 connection = tmp;
466 }
467 }
468 if(connection == NULL) {
469 printf("%s(): connection still NULL, no dev found\n",
470 __func__);
471 return(-1);
472 }
473
474 /* NG_MKMESSAGE(msg, cookie, cmdid, len, how) */
475 NG_MKMESSAGE(msg, NGM_DEVICE_COOKIE, cmd, sizeof(struct ngd_param_s),
476 M_NOWAIT);
477 if (msg == NULL) {
478 printf("%s(): msg == NULL\n", __func__);
479 goto nomsg;
480 }
481
482 /* pass the ioctl data into the ->data area */
483 datap = (struct ngd_param_s *)msg->data;
484 datap->p = addr;
485
486 /*ng_send_msg(node_p here, struct ng_mesg *msg,
487 const char *address, struct ng_mesg **resp); */
488 error = ng_send_msg(sc->node, msg,
489 NG_HOOK_NAME(connection->active_hook), NULL);
490 if(error)
491 printf("%s(): ng_send_msg() error: %d\n", __func__, error);
492
493nomsg:
494
495 return(0);
496}
497
498
499/*
500 * This function is called when a read(2) is done to our device.
501 * We pass the data available in kernelspace on into userland using
502 * uiomove.
503 */
504static int
505ngdread(dev_t dev, struct uio *uio, int flag)
506{
507 int ret = 0, amnt;
508 char buffer[uio->uio_resid+1];
509 struct ngd_softc *sc = &ngd_softc;
510 struct ngd_connection * connection = NULL;
511 struct ngd_connection * tmp;
512
513#ifdef NGD_DEBUG
514 printf("%s()\n", __func__);
515#endif /* NGD_DEBUG */
516
517 SLIST_FOREACH(tmp, &sc->head, links) {
518 if(tmp->ngddev == dev) {
519 connection = tmp;
520 }
521 }
522 if(connection == NULL) {
523 printf("%s(): connection still NULL, no dev found\n", __func__);
524 return(-1);
525 }
526
527 while ( ( uio->uio_resid > 0 ) && ( connection->loc > 0 ) ) {
528 amnt = MIN(uio->uio_resid, connection->loc);
529
530 memcpy(buffer, connection->readq, amnt);
531 memcpy(connection->readq, connection->readq+amnt,
532 connection->loc-amnt);
533 connection->loc -= amnt;
534
535 ret = uiomove((caddr_t)buffer, amnt, uio);
536 if(ret != 0)
537 goto error;
538
539 }
540 return(0);
541
542error:
543 printf("%s(): uiomove returns error %d\n", __func__, ret);
544 /* do error cleanup here */
545 return(ret);
546}
547
548
549/*
550 * This function is called when our device is written to.
551 * We read the data from userland into our local buffer and pass it on
552 * into the remote hook.
553 *
554 */
555static int
556ngdwrite(dev_t dev, struct uio *uio, int flag)
557{
558 int ret;
559 int error = 0;
560 struct mbuf *m;
561 char buffer[uio->uio_resid];
562 int len = uio->uio_resid;
563 struct ngd_softc *sc =& ngd_softc;
564 struct ngd_connection * connection = NULL;
565 struct ngd_connection * tmp;
566
567#ifdef NGD_DEBUG
568 printf("%s()\n", __func__);
569#endif /* NGD_DEBUG */
570
571 SLIST_FOREACH(tmp, &sc->head, links) {
572 if(tmp->ngddev == dev) {
573 connection = tmp;
574 }
575 }
576
577 if(connection == NULL) {
578 printf("%s(): connection still NULL, no dev found\n", __func__);
579 return(-1);
580 }
581
582 if (len > 0) {
583 if ((ret = uiomove((caddr_t)buffer, len, uio)) != 0)
584 goto error;
585 } else
586 printf("%s(): len <= 0 : supposed to happen?!\n", __func__);
587
588 m = m_devget(buffer, len, 0, NULL, NULL);
589
590 NG_SEND_DATA_ONLY(error, connection->active_hook, m);
591
592 return(0);
593
594error:
595 /* do error cleanup here */
596 printf("%s(): uiomove returned err: %d\n", __func__, ret);
597
598 return(ret);
599}
600
601/*
602 * we are being polled/selected
603 * check if there is data available for read
604 */
605static int
606ngdpoll(dev_t dev, int events, struct thread *td)
607{
608 int revents = 0;
609 struct ngd_softc *sc = &ngd_softc;
610 struct ngd_connection * connection = NULL;
611 struct ngd_connection * tmp;
612
613
614 if (events & (POLLIN | POLLRDNORM)) {
615 /* get the connection we have to know the loc from */
616 SLIST_FOREACH(tmp, &sc->head, links) {
617 if(tmp->ngddev == dev) {
618 connection = tmp;
619 }
620 }
621 if(connection == NULL) {
622 printf("%s(): ERROR: connection still NULL, "
623 "no dev found\n", __func__);
624 return(-1);
625 }
626
627 if (connection->loc > 0)
628 revents |= events & (POLLIN | POLLRDNORM);
629 }
630
631 return(revents);
632}