Change the kernel dev_t, representing a pointer to a specinfo structure,
[dragonfly.git] / sys / netgraph / ng_device.c
CommitLineData
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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 $
b13267a5 32 * $DragonFly: src/sys/netgraph/ng_device.c,v 1.8 2006/09/10 01:26:40 dillon Exp $
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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
b13267a5 89 cdev_t ngddev;
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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 = {
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122 /* name */ "ngd",
123 /* maj */ NGD_CDEV_MAJOR,
124 /* flags */ 0,
125 /* port */ NULL,
455fcd7e 126 /* clone */ NULL,
fabb8ceb 127
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128 /* open */ ngdopen,
129 /* close */ ngdclose,
130 /* read */ ngdread,
131 /* write */ ngdwrite,
132 /* ioctl */ ngdioctl,
133 /* poll */ ngdpoll,
134 /* mmap */ nommap,
135 /* strategy */ nostrategy,
984263bc 136 /* dump */ nodump,
fabb8ceb 137 /* psize */ nopsize
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138};
139
140/*
141 * this holds all the stuff that should be done at load time
142 */
143static int
144ng_device_mod_event(module_t mod, int event, void *data)
145{
146 int error = 0;
147
148#ifdef NGD_DEBUG
149 printf("%s()\n", __func__);
150#endif /* NGD_DEBUG */
151
152 switch (event) {
153 case MOD_LOAD:
e4c9c0c8 154 cdevsw_add(&ngd_cdevsw, 0, 0);
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155 ng_device_init();
156 break;
157
158 case MOD_UNLOAD:
159 /* XXX do we need to do something specific ? */
160 /* ng_device_breakdown */
e4c9c0c8 161 cdevsw_remove(&ngd_cdevsw, 0, 0);
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162 error = EBUSY; /* no unload! */
163 break;
164
165
166 default:
167 error = EOPNOTSUPP;
168 break;
169 }
170
171 return(error);
172}
173
174
175static int
e253fad8 176ng_device_init(void)
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177{
178 struct ngd_softc *sc = &ngd_softc;
179
180#ifdef NGD_DEBUG
181 printf("%s()\n", __func__);
182#endif /* NGD_DEBUG */
183
184 SLIST_INIT(&sc->head);
185
186 if (ng_make_node_common(&typestruct, &sc->node) != 0) {
187 printf("%s(): ng_make_node_common failed\n", __func__);
188 return(ENXIO);
189 }
190 sprintf(sc->nodename, "%s", NG_DEVICE_NODE_TYPE);
191 if (ng_name_node(sc->node, sc->nodename)) {
192 NG_NODE_UNREF(sc->node); /* make it go away again */
193 printf("%s(): ng_name_node failed\n", __func__);
194 return(ENXIO);
195 }
196 NG_NODE_SET_PRIVATE(sc->node, sc);
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197
198 return(0);
199}
200
201/*
202 * don't allow to be created, only the device can do that
203 */
204static int
205ng_device_cons(node_p node)
206{
207
208#ifdef NGD_DEBUG
209 printf("%s()\n", __func__);
210#endif /* NGD_DEBUG */
211
212 return(EINVAL);
213}
214
215/*
216 * Receive control message. We just free it.
217 */
218static int
219ng_device_rcvmsg(node_p node,
220 struct ng_mesg *msg, const char *retaddr, struct ng_mesg **rptr)
221{
222 FREE(msg, M_NETGRAPH);
223 return(ENOTTY);
224}
225
226static int
e253fad8 227get_free_unit(void)
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228{
229 struct ngd_connection *tmp = NULL;
230 struct ngd_softc *sc = &ngd_softc;
231 int n = 0;
232 int unit = -1;
233
234#ifdef NGD_DEBUG
235 printf("%s()\n", __func__);
236#endif /* NGD_DEBUG */
237
238 /* When there is no list yet, the first device unit is always 0. */
239 if SLIST_EMPTY(&sc->head) {
240 unit = 0;
241 return(unit);
242 }
243
244 /* Just do a brute force loop to find the first free unit that is
245 * smaller than MAX_NGD.
246 * Set MAX_NGD to a large value, doesn't impact performance.
247 */
248 for(n = 0;n<MAX_NGD && unit == -1;n++) {
249 SLIST_FOREACH(tmp, &sc->head, links) {
250
251 if(tmp->unit == n) {
252 unit = -1;
253 break;
254 }
255 unit = n;
256 }
257 }
258
259 return(unit);
260}
261
262/*
263 * incoming hook
264 */
265static int
266ng_device_newhook(node_p node, hook_p hook, const char *name)
267{
268 struct ngd_softc *sc = &ngd_softc;
269 struct ngd_connection * new_connection = NULL;
270
271#ifdef NGD_DEBUG
272 printf("%s()\n", __func__);
273#endif /* NGD_DEBUG */
274
efda3bd0 275 new_connection = kmalloc(sizeof(struct ngd_connection), M_DEVBUF, M_NOWAIT);
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276 if(new_connection == NULL) {
277 printf("%s(): ERROR: new_connection == NULL\n", __func__);
278 return(-1);
279 }
280
281 new_connection->unit = get_free_unit();
282 if(new_connection->unit<0) {
283 printf("%s: No free unit found by get_free_unit(), "
284 "increas MAX_NGD\n", __func__);
efda3bd0 285 kfree(new_connection, M_DEVBUF);
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286 return(-1);
287 }
288 new_connection->ngddev = make_dev(&ngd_cdevsw,
289 new_connection->unit, 0, 0, 0600, "ngd%d", new_connection->unit);
290 if(new_connection->ngddev == NULL) {
291 printf("%s(): make_dev failed\n", __func__);
292 SLIST_REMOVE(&sc->head, new_connection, ngd_connection, links);
efda3bd0 293 kfree(new_connection, M_DEVBUF);
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294 return(-1);
295 }
296
297 new_connection->readq =
efda3bd0 298 kmalloc(sizeof(char)*NGD_QUEUE_SIZE, M_DEVBUF, M_NOWAIT | M_ZERO);
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299 if(new_connection->readq == NULL) {
300 printf("%s(): readq malloc failed\n", __func__);
301 destroy_dev(new_connection->ngddev);
302 SLIST_REMOVE(&sc->head, new_connection, ngd_connection, links);
efda3bd0 303 kfree(new_connection, M_DEVBUF);
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304 return(-1);
305 }
306
307 /* point to begin of buffer */
308 new_connection->loc = 0;
309 new_connection->active_hook = hook;
310
311 SLIST_INSERT_HEAD(&sc->head, new_connection, links);
312
313 return(0);
314}
315
316/*
317 * we gave ok to a new hook
318 * now connect
319 */
320static int
321ng_device_connect(hook_p hook)
322{
323
324#ifdef NGD_DEBUG
325 printf("%s()\n", __func__);
326#endif /* NGD_DEBUG */
327
328 return(0);
329}
330
331
332/*
333 * Receive data from hook
334 */
335static int
336ng_device_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
337{
338 struct ngd_softc *sc = &ngd_softc;
339 struct ngd_connection * connection = NULL;
340 struct ngd_connection * tmp;
341 char *buffer;
342
343#ifdef NGD_DEBUG
344 printf("%s()\n", __func__);
345#endif /* NGD_DEBUG */
346
347 SLIST_FOREACH(tmp, &sc->head, links) {
348 if(tmp->active_hook == hook) {
349 connection = tmp;
350 }
351 }
352 if(connection == NULL) {
353 printf("%s(): connection still NULL, no hook found\n", __func__);
354 return(-1);
355 }
356
357 NG_FREE_META(meta);
358
359 m = m_pullup(m, m->m_len);
360 if(m == NULL) {
361 printf("%s(): ERROR: m_pullup failed\n", __func__);
362 return(-1);
363 }
364
efda3bd0 365 buffer = kmalloc(sizeof(char)*m->m_len, M_DEVBUF, M_NOWAIT | M_ZERO);
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366 if(buffer == NULL) {
367 printf("%s(): ERROR: buffer malloc failed\n", __func__);
368 return(-1);
369 }
370
371 buffer = mtod(m, char *);
372
373 if( (connection->loc+m->m_len) < NGD_QUEUE_SIZE) {
374 memcpy(connection->readq+connection->loc, buffer, m->m_len);
375 connection->loc += m->m_len;
376 } else
377 printf("%s(): queue full, first read out a bit\n", __func__);
378
efda3bd0 379 kfree(buffer, M_DEVBUF);
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380
381 return(0);
382}
383
384/*
385 * Removal of the last link destroys the node
386 */
387static int
388ng_device_disconnect(hook_p hook)
389{
390 struct ngd_softc *sc = &ngd_softc;
391 struct ngd_connection * connection = NULL;
392 struct ngd_connection * tmp;
393
394#ifdef NGD_DEBUG
395 printf("%s()\n", __func__);
396#endif /* NGD_DEBUG */
397
398 SLIST_FOREACH(tmp, &sc->head, links) {
399 if(tmp->active_hook == hook) {
400 connection = tmp;
401 }
402 }
403 if(connection == NULL) {
404 printf("%s(): connection still NULL, no hook found\n",
405 __func__);
406 return(-1);
407 }
408
efda3bd0 409 kfree(connection->readq, M_DEVBUF);
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410
411 destroy_dev(connection->ngddev);
412
413 SLIST_REMOVE(&sc->head, connection, ngd_connection, links);
414
415 return(0);
416}
417/*
418 * the device is opened
419 */
420static int
b13267a5 421ngdopen(cdev_t dev, int flag, int mode, struct thread *td)
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422{
423
424#ifdef NGD_DEBUG
425 printf("%s()\n", __func__);
426#endif /* NGD_DEBUG */
427
428 return(0);
429}
430
431/*
432 * the device is closed
433 */
434static int
b13267a5 435ngdclose(cdev_t dev, int flag, int mode, struct thread *td)
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436{
437
438#ifdef NGD_DEBUG
439 printf("%s()\n", __func__);
440#endif
441
442 return(0);
443}
444
445
446/*
447 * process ioctl
448 *
449 * they are translated into netgraph messages and passed on
450 *
451 */
452static int
b13267a5 453ngdioctl(cdev_t dev, u_long cmd, caddr_t addr, int flag, struct thread *td)
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454{
455 struct ngd_softc *sc = &ngd_softc;
456 struct ngd_connection * connection = NULL;
457 struct ngd_connection * tmp;
458 int error = 0;
459 struct ng_mesg *msg;
460 struct ngd_param_s * datap;
461
462#ifdef NGD_DEBUG
463 printf("%s()\n", __func__);
464#endif /* NGD_DEBUG */
465
466 SLIST_FOREACH(tmp, &sc->head, links) {
467 if(tmp->ngddev == dev) {
468 connection = tmp;
469 }
470 }
471 if(connection == NULL) {
472 printf("%s(): connection still NULL, no dev found\n",
473 __func__);
474 return(-1);
475 }
476
477 /* NG_MKMESSAGE(msg, cookie, cmdid, len, how) */
478 NG_MKMESSAGE(msg, NGM_DEVICE_COOKIE, cmd, sizeof(struct ngd_param_s),
479 M_NOWAIT);
480 if (msg == NULL) {
481 printf("%s(): msg == NULL\n", __func__);
482 goto nomsg;
483 }
484
485 /* pass the ioctl data into the ->data area */
486 datap = (struct ngd_param_s *)msg->data;
487 datap->p = addr;
488
489 /*ng_send_msg(node_p here, struct ng_mesg *msg,
490 const char *address, struct ng_mesg **resp); */
491 error = ng_send_msg(sc->node, msg,
492 NG_HOOK_NAME(connection->active_hook), NULL);
493 if(error)
494 printf("%s(): ng_send_msg() error: %d\n", __func__, error);
495
496nomsg:
497
498 return(0);
499}
500
501
502/*
503 * This function is called when a read(2) is done to our device.
504 * We pass the data available in kernelspace on into userland using
505 * uiomove.
506 */
507static int
b13267a5 508ngdread(cdev_t dev, struct uio *uio, int flag)
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509{
510 int ret = 0, amnt;
511 char buffer[uio->uio_resid+1];
512 struct ngd_softc *sc = &ngd_softc;
513 struct ngd_connection * connection = NULL;
514 struct ngd_connection * tmp;
515
516#ifdef NGD_DEBUG
517 printf("%s()\n", __func__);
518#endif /* NGD_DEBUG */
519
520 SLIST_FOREACH(tmp, &sc->head, links) {
521 if(tmp->ngddev == dev) {
522 connection = tmp;
523 }
524 }
525 if(connection == NULL) {
526 printf("%s(): connection still NULL, no dev found\n", __func__);
527 return(-1);
528 }
529
530 while ( ( uio->uio_resid > 0 ) && ( connection->loc > 0 ) ) {
531 amnt = MIN(uio->uio_resid, connection->loc);
532
533 memcpy(buffer, connection->readq, amnt);
534 memcpy(connection->readq, connection->readq+amnt,
535 connection->loc-amnt);
536 connection->loc -= amnt;
537
538 ret = uiomove((caddr_t)buffer, amnt, uio);
539 if(ret != 0)
540 goto error;
541
542 }
543 return(0);
544
545error:
546 printf("%s(): uiomove returns error %d\n", __func__, ret);
547 /* do error cleanup here */
548 return(ret);
549}
550
551
552/*
553 * This function is called when our device is written to.
554 * We read the data from userland into our local buffer and pass it on
555 * into the remote hook.
556 *
557 */
558static int
b13267a5 559ngdwrite(cdev_t dev, struct uio *uio, int flag)
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560{
561 int ret;
562 int error = 0;
563 struct mbuf *m;
564 char buffer[uio->uio_resid];
565 int len = uio->uio_resid;
566 struct ngd_softc *sc =& ngd_softc;
567 struct ngd_connection * connection = NULL;
568 struct ngd_connection * tmp;
569
570#ifdef NGD_DEBUG
571 printf("%s()\n", __func__);
572#endif /* NGD_DEBUG */
573
574 SLIST_FOREACH(tmp, &sc->head, links) {
575 if(tmp->ngddev == dev) {
576 connection = tmp;
577 }
578 }
579
580 if(connection == NULL) {
581 printf("%s(): connection still NULL, no dev found\n", __func__);
582 return(-1);
583 }
584
585 if (len > 0) {
586 if ((ret = uiomove((caddr_t)buffer, len, uio)) != 0)
587 goto error;
588 } else
589 printf("%s(): len <= 0 : supposed to happen?!\n", __func__);
590
591 m = m_devget(buffer, len, 0, NULL, NULL);
592
593 NG_SEND_DATA_ONLY(error, connection->active_hook, m);
594
595 return(0);
596
597error:
598 /* do error cleanup here */
599 printf("%s(): uiomove returned err: %d\n", __func__, ret);
600
601 return(ret);
602}
603
604/*
605 * we are being polled/selected
606 * check if there is data available for read
607 */
608static int
b13267a5 609ngdpoll(cdev_t dev, int events, struct thread *td)
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610{
611 int revents = 0;
612 struct ngd_softc *sc = &ngd_softc;
613 struct ngd_connection * connection = NULL;
614 struct ngd_connection * tmp;
615
616
617 if (events & (POLLIN | POLLRDNORM)) {
618 /* get the connection we have to know the loc from */
619 SLIST_FOREACH(tmp, &sc->head, links) {
620 if(tmp->ngddev == dev) {
621 connection = tmp;
622 }
623 }
624 if(connection == NULL) {
625 printf("%s(): ERROR: connection still NULL, "
626 "no dev found\n", __func__);
627 return(-1);
628 }
629
630 if (connection->loc > 0)
631 revents |= events & (POLLIN | POLLRDNORM);
632 }
633
634 return(revents);
635}