Fix a minor compile-time errors when INVARIANTS is not defined.
[dragonfly.git] / sys / netgraph / ng_device.c
CommitLineData
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 $
1de703da 32 * $DragonFly: src/sys/netgraph/ng_device.c,v 1.2 2003/06/17 04:28:49 dillon Exp $
984263bc
MD
33 *
34 */
35
36#include <sys/param.h>
37#include <sys/systm.h>
38#include <sys/kernel.h>
39#include <sys/mbuf.h>
40#include <sys/uio.h>
41#include <sys/queue.h>
42#include <sys/malloc.h>
43#include <sys/conf.h>
44#include <sys/poll.h>
45#include <sys/ioccom.h>
46
47#include <netgraph/ng_message.h>
48#include <netgraph/netgraph.h>
49
50#include "ng_device.h"
51
52/* turn this on for verbose messages */
53#define NGD_DEBUG
54
55/* Netgraph methods */
56static ng_constructor_t ng_device_cons;
57static ng_rcvmsg_t ng_device_rcvmsg;
58static ng_newhook_t ng_device_newhook;
59static ng_connect_t ng_device_connect;
60static ng_rcvdata_t ng_device_rcvdata;
61static ng_disconnect_t ng_device_disconnect;
62static int ng_device_mod_event(module_t mod, int event, void *data);
63
64static int ng_device_init(void);
65static int get_free_unit(void);
66
67/* Netgraph type */
68static struct ng_type typestruct = {
69 NG_VERSION, /* version */
70 NG_DEVICE_NODE_TYPE, /* name */
71 ng_device_mod_event, /* modevent */
72 ng_device_cons, /* constructor */
73 ng_device_rcvmsg, /* receive msg */
74 NULL, /* shutdown */
75 ng_device_newhook, /* newhook */
76 NULL, /* findhook */
77 ng_device_connect, /* connect */
78 ng_device_rcvdata, /* receive data */
79 ng_device_rcvdata, /* receive queued data */
80 ng_device_disconnect, /* disconnect */
81 NULL
82};
83NETGRAPH_INIT(device, &typestruct);
84
85/* per hook data */
86struct ngd_connection {
87 SLIST_ENTRY(ngd_connection) links;
88
89 dev_t ngddev;
90 struct ng_hook *active_hook;
91 char *readq;
92 int loc;
93 int unit;
94};
95
96/* global data */
97struct ngd_softc {
98 SLIST_HEAD(, ngd_connection) head;
99
100 node_p node;
101 char nodename[NG_NODELEN + 1];
102} ngd_softc;
103
104/* helper definition */
105#define MIN(a, b) ((a) < (b) ? (a) : (b))
106
107/* the per connection receiving queue maximum */
108#define NGD_QUEUE_SIZE (1024*10)
109
110/* Maximum number of NGD devices */
111#define MAX_NGD 25 /* should be more than enough for now */
112
113static d_close_t ngdclose;
114static d_open_t ngdopen;
115static d_read_t ngdread;
116static d_write_t ngdwrite;
117static d_ioctl_t ngdioctl;
118static d_poll_t ngdpoll;
119
120#define NGD_CDEV_MAJOR 20
121static struct cdevsw ngd_cdevsw = {
122 /* open */ ngdopen,
123 /* close */ ngdclose,
124 /* read */ ngdread,
125 /* write */ ngdwrite,
126 /* ioctl */ ngdioctl,
127 /* poll */ ngdpoll,
128 /* mmap */ nommap,
129 /* strategy */ nostrategy,
130 /* name */ "ngd",
131 /* maj */ NGD_CDEV_MAJOR,
132 /* dump */ nodump,
133 /* psize */ nopsize,
134 /* flags */ 0,
135 /* bmaj */ -1
136};
137
138/*
139 * this holds all the stuff that should be done at load time
140 */
141static int
142ng_device_mod_event(module_t mod, int event, void *data)
143{
144 int error = 0;
145
146#ifdef NGD_DEBUG
147 printf("%s()\n", __func__);
148#endif /* NGD_DEBUG */
149
150 switch (event) {
151 case MOD_LOAD:
152 ng_device_init();
153 break;
154
155 case MOD_UNLOAD:
156 /* XXX do we need to do something specific ? */
157 /* ng_device_breakdown */
158 /* cdevsw_remove(&ngd_cdevsw);*/
159 error = EBUSY; /* no unload! */
160 break;
161
162
163 default:
164 error = EOPNOTSUPP;
165 break;
166 }
167
168 return(error);
169}
170
171
172static int
173ng_device_init()
174{
175 struct ngd_softc *sc = &ngd_softc;
176
177#ifdef NGD_DEBUG
178 printf("%s()\n", __func__);
179#endif /* NGD_DEBUG */
180
181 SLIST_INIT(&sc->head);
182
183 if (ng_make_node_common(&typestruct, &sc->node) != 0) {
184 printf("%s(): ng_make_node_common failed\n", __func__);
185 return(ENXIO);
186 }
187 sprintf(sc->nodename, "%s", NG_DEVICE_NODE_TYPE);
188 if (ng_name_node(sc->node, sc->nodename)) {
189 NG_NODE_UNREF(sc->node); /* make it go away again */
190 printf("%s(): ng_name_node failed\n", __func__);
191 return(ENXIO);
192 }
193 NG_NODE_SET_PRIVATE(sc->node, sc);
194 cdevsw_add(&ngd_cdevsw);
195
196 return(0);
197}
198
199/*
200 * don't allow to be created, only the device can do that
201 */
202static int
203ng_device_cons(node_p node)
204{
205
206#ifdef NGD_DEBUG
207 printf("%s()\n", __func__);
208#endif /* NGD_DEBUG */
209
210 return(EINVAL);
211}
212
213/*
214 * Receive control message. We just free it.
215 */
216static int
217ng_device_rcvmsg(node_p node,
218 struct ng_mesg *msg, const char *retaddr, struct ng_mesg **rptr)
219{
220 FREE(msg, M_NETGRAPH);
221 return(ENOTTY);
222}
223
224static int
225get_free_unit()
226{
227 struct ngd_connection *tmp = NULL;
228 struct ngd_softc *sc = &ngd_softc;
229 int n = 0;
230 int unit = -1;
231
232#ifdef NGD_DEBUG
233 printf("%s()\n", __func__);
234#endif /* NGD_DEBUG */
235
236 /* When there is no list yet, the first device unit is always 0. */
237 if SLIST_EMPTY(&sc->head) {
238 unit = 0;
239 return(unit);
240 }
241
242 /* Just do a brute force loop to find the first free unit that is
243 * smaller than MAX_NGD.
244 * Set MAX_NGD to a large value, doesn't impact performance.
245 */
246 for(n = 0;n<MAX_NGD && unit == -1;n++) {
247 SLIST_FOREACH(tmp, &sc->head, links) {
248
249 if(tmp->unit == n) {
250 unit = -1;
251 break;
252 }
253 unit = n;
254 }
255 }
256
257 return(unit);
258}
259
260/*
261 * incoming hook
262 */
263static int
264ng_device_newhook(node_p node, hook_p hook, const char *name)
265{
266 struct ngd_softc *sc = &ngd_softc;
267 struct ngd_connection * new_connection = NULL;
268
269#ifdef NGD_DEBUG
270 printf("%s()\n", __func__);
271#endif /* NGD_DEBUG */
272
273 new_connection = malloc(sizeof(struct ngd_connection), M_DEVBUF, M_NOWAIT);
274 if(new_connection == NULL) {
275 printf("%s(): ERROR: new_connection == NULL\n", __func__);
276 return(-1);
277 }
278
279 new_connection->unit = get_free_unit();
280 if(new_connection->unit<0) {
281 printf("%s: No free unit found by get_free_unit(), "
282 "increas MAX_NGD\n", __func__);
283 free(new_connection, M_DEVBUF);
284 return(-1);
285 }
286 new_connection->ngddev = make_dev(&ngd_cdevsw,
287 new_connection->unit, 0, 0, 0600, "ngd%d", new_connection->unit);
288 if(new_connection->ngddev == NULL) {
289 printf("%s(): make_dev failed\n", __func__);
290 SLIST_REMOVE(&sc->head, new_connection, ngd_connection, links);
291 free(new_connection, M_DEVBUF);
292 return(-1);
293 }
294
295 new_connection->readq =
296 malloc(sizeof(char)*NGD_QUEUE_SIZE, M_DEVBUF, M_NOWAIT | M_ZERO);
297 if(new_connection->readq == NULL) {
298 printf("%s(): readq malloc failed\n", __func__);
299 destroy_dev(new_connection->ngddev);
300 SLIST_REMOVE(&sc->head, new_connection, ngd_connection, links);
301 free(new_connection, M_DEVBUF);
302 return(-1);
303 }
304
305 /* point to begin of buffer */
306 new_connection->loc = 0;
307 new_connection->active_hook = hook;
308
309 SLIST_INSERT_HEAD(&sc->head, new_connection, links);
310
311 return(0);
312}
313
314/*
315 * we gave ok to a new hook
316 * now connect
317 */
318static int
319ng_device_connect(hook_p hook)
320{
321
322#ifdef NGD_DEBUG
323 printf("%s()\n", __func__);
324#endif /* NGD_DEBUG */
325
326 return(0);
327}
328
329
330/*
331 * Receive data from hook
332 */
333static int
334ng_device_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
335{
336 struct ngd_softc *sc = &ngd_softc;
337 struct ngd_connection * connection = NULL;
338 struct ngd_connection * tmp;
339 char *buffer;
340
341#ifdef NGD_DEBUG
342 printf("%s()\n", __func__);
343#endif /* NGD_DEBUG */
344
345 SLIST_FOREACH(tmp, &sc->head, links) {
346 if(tmp->active_hook == hook) {
347 connection = tmp;
348 }
349 }
350 if(connection == NULL) {
351 printf("%s(): connection still NULL, no hook found\n", __func__);
352 return(-1);
353 }
354
355 NG_FREE_META(meta);
356
357 m = m_pullup(m, m->m_len);
358 if(m == NULL) {
359 printf("%s(): ERROR: m_pullup failed\n", __func__);
360 return(-1);
361 }
362
363 buffer = malloc(sizeof(char)*m->m_len, M_DEVBUF, M_NOWAIT | M_ZERO);
364 if(buffer == NULL) {
365 printf("%s(): ERROR: buffer malloc failed\n", __func__);
366 return(-1);
367 }
368
369 buffer = mtod(m, char *);
370
371 if( (connection->loc+m->m_len) < NGD_QUEUE_SIZE) {
372 memcpy(connection->readq+connection->loc, buffer, m->m_len);
373 connection->loc += m->m_len;
374 } else
375 printf("%s(): queue full, first read out a bit\n", __func__);
376
377 free(buffer, M_DEVBUF);
378
379 return(0);
380}
381
382/*
383 * Removal of the last link destroys the node
384 */
385static int
386ng_device_disconnect(hook_p hook)
387{
388 struct ngd_softc *sc = &ngd_softc;
389 struct ngd_connection * connection = NULL;
390 struct ngd_connection * tmp;
391
392#ifdef NGD_DEBUG
393 printf("%s()\n", __func__);
394#endif /* NGD_DEBUG */
395
396 SLIST_FOREACH(tmp, &sc->head, links) {
397 if(tmp->active_hook == hook) {
398 connection = tmp;
399 }
400 }
401 if(connection == NULL) {
402 printf("%s(): connection still NULL, no hook found\n",
403 __func__);
404 return(-1);
405 }
406
407 free(connection->readq, M_DEVBUF);
408
409 destroy_dev(connection->ngddev);
410
411 SLIST_REMOVE(&sc->head, connection, ngd_connection, links);
412
413 return(0);
414}
415/*
416 * the device is opened
417 */
418static int
419ngdopen(dev_t dev, int flag, int mode, struct thread *td)
420{
421
422#ifdef NGD_DEBUG
423 printf("%s()\n", __func__);
424#endif /* NGD_DEBUG */
425
426 return(0);
427}
428
429/*
430 * the device is closed
431 */
432static int
433ngdclose(dev_t dev, int flag, int mode, struct thread *td)
434{
435
436#ifdef NGD_DEBUG
437 printf("%s()\n", __func__);
438#endif
439
440 return(0);
441}
442
443
444/*
445 * process ioctl
446 *
447 * they are translated into netgraph messages and passed on
448 *
449 */
450static int
451ngdioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct thread *td)
452{
453 struct ngd_softc *sc = &ngd_softc;
454 struct ngd_connection * connection = NULL;
455 struct ngd_connection * tmp;
456 int error = 0;
457 struct ng_mesg *msg;
458 struct ngd_param_s * datap;
459
460#ifdef NGD_DEBUG
461 printf("%s()\n", __func__);
462#endif /* NGD_DEBUG */
463
464 SLIST_FOREACH(tmp, &sc->head, links) {
465 if(tmp->ngddev == dev) {
466 connection = tmp;
467 }
468 }
469 if(connection == NULL) {
470 printf("%s(): connection still NULL, no dev found\n",
471 __func__);
472 return(-1);
473 }
474
475 /* NG_MKMESSAGE(msg, cookie, cmdid, len, how) */
476 NG_MKMESSAGE(msg, NGM_DEVICE_COOKIE, cmd, sizeof(struct ngd_param_s),
477 M_NOWAIT);
478 if (msg == NULL) {
479 printf("%s(): msg == NULL\n", __func__);
480 goto nomsg;
481 }
482
483 /* pass the ioctl data into the ->data area */
484 datap = (struct ngd_param_s *)msg->data;
485 datap->p = addr;
486
487 /*ng_send_msg(node_p here, struct ng_mesg *msg,
488 const char *address, struct ng_mesg **resp); */
489 error = ng_send_msg(sc->node, msg,
490 NG_HOOK_NAME(connection->active_hook), NULL);
491 if(error)
492 printf("%s(): ng_send_msg() error: %d\n", __func__, error);
493
494nomsg:
495
496 return(0);
497}
498
499
500/*
501 * This function is called when a read(2) is done to our device.
502 * We pass the data available in kernelspace on into userland using
503 * uiomove.
504 */
505static int
506ngdread(dev_t dev, struct uio *uio, int flag)
507{
508 int ret = 0, amnt;
509 char buffer[uio->uio_resid+1];
510 struct ngd_softc *sc = &ngd_softc;
511 struct ngd_connection * connection = NULL;
512 struct ngd_connection * tmp;
513
514#ifdef NGD_DEBUG
515 printf("%s()\n", __func__);
516#endif /* NGD_DEBUG */
517
518 SLIST_FOREACH(tmp, &sc->head, links) {
519 if(tmp->ngddev == dev) {
520 connection = tmp;
521 }
522 }
523 if(connection == NULL) {
524 printf("%s(): connection still NULL, no dev found\n", __func__);
525 return(-1);
526 }
527
528 while ( ( uio->uio_resid > 0 ) && ( connection->loc > 0 ) ) {
529 amnt = MIN(uio->uio_resid, connection->loc);
530
531 memcpy(buffer, connection->readq, amnt);
532 memcpy(connection->readq, connection->readq+amnt,
533 connection->loc-amnt);
534 connection->loc -= amnt;
535
536 ret = uiomove((caddr_t)buffer, amnt, uio);
537 if(ret != 0)
538 goto error;
539
540 }
541 return(0);
542
543error:
544 printf("%s(): uiomove returns error %d\n", __func__, ret);
545 /* do error cleanup here */
546 return(ret);
547}
548
549
550/*
551 * This function is called when our device is written to.
552 * We read the data from userland into our local buffer and pass it on
553 * into the remote hook.
554 *
555 */
556static int
557ngdwrite(dev_t dev, struct uio *uio, int flag)
558{
559 int ret;
560 int error = 0;
561 struct mbuf *m;
562 char buffer[uio->uio_resid];
563 int len = uio->uio_resid;
564 struct ngd_softc *sc =& ngd_softc;
565 struct ngd_connection * connection = NULL;
566 struct ngd_connection * tmp;
567
568#ifdef NGD_DEBUG
569 printf("%s()\n", __func__);
570#endif /* NGD_DEBUG */
571
572 SLIST_FOREACH(tmp, &sc->head, links) {
573 if(tmp->ngddev == dev) {
574 connection = tmp;
575 }
576 }
577
578 if(connection == NULL) {
579 printf("%s(): connection still NULL, no dev found\n", __func__);
580 return(-1);
581 }
582
583 if (len > 0) {
584 if ((ret = uiomove((caddr_t)buffer, len, uio)) != 0)
585 goto error;
586 } else
587 printf("%s(): len <= 0 : supposed to happen?!\n", __func__);
588
589 m = m_devget(buffer, len, 0, NULL, NULL);
590
591 NG_SEND_DATA_ONLY(error, connection->active_hook, m);
592
593 return(0);
594
595error:
596 /* do error cleanup here */
597 printf("%s(): uiomove returned err: %d\n", __func__, ret);
598
599 return(ret);
600}
601
602/*
603 * we are being polled/selected
604 * check if there is data available for read
605 */
606static int
607ngdpoll(dev_t dev, int events, struct thread *td)
608{
609 int revents = 0;
610 struct ngd_softc *sc = &ngd_softc;
611 struct ngd_connection * connection = NULL;
612 struct ngd_connection * tmp;
613
614
615 if (events & (POLLIN | POLLRDNORM)) {
616 /* get the connection we have to know the loc from */
617 SLIST_FOREACH(tmp, &sc->head, links) {
618 if(tmp->ngddev == dev) {
619 connection = tmp;
620 }
621 }
622 if(connection == NULL) {
623 printf("%s(): ERROR: connection still NULL, "
624 "no dev found\n", __func__);
625 return(-1);
626 }
627
628 if (connection->loc > 0)
629 revents |= events & (POLLIN | POLLRDNORM);
630 }
631
632 return(revents);
633}