1/*-
2 * Copyright (c) 2008 Ed Schouten <ed@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
| 1/*-
2 * Copyright (c) 2008 Ed Schouten <ed@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
|
28__FBSDID("$FreeBSD: head/sys/dev/snp/snp.c 196452 2009-08-23 08:04:40Z ed $");
| 28__FBSDID("$FreeBSD: head/sys/dev/snp/snp.c 223575 2011-06-26 18:26:20Z ed $");
|
29
30#include <sys/param.h>
31#include <sys/conf.h>
32#include <sys/fcntl.h>
33#include <sys/filio.h>
34#include <sys/kernel.h>
35#include <sys/malloc.h>
36#include <sys/module.h>
37#include <sys/poll.h>
38#include <sys/proc.h>
39#include <sys/snoop.h>
40#include <sys/sx.h>
41#include <sys/systm.h>
42#include <sys/tty.h>
43#include <sys/uio.h>
44
45static struct cdev *snp_dev;
46static MALLOC_DEFINE(M_SNP, "snp", "tty snoop device");
47
48/* XXX: should be mtx, but TTY can be locked by Giant. */
49#if 0
50static struct mtx snp_register_lock;
51MTX_SYSINIT(snp_register_lock, &snp_register_lock,
52 "tty snoop registration", MTX_DEF);
53#define SNP_LOCK() mtx_lock(&snp_register_lock)
54#define SNP_UNLOCK() mtx_unlock(&snp_register_lock)
55#else
56static struct sx snp_register_lock;
57SX_SYSINIT(snp_register_lock, &snp_register_lock,
58 "tty snoop registration");
59#define SNP_LOCK() sx_xlock(&snp_register_lock)
60#define SNP_UNLOCK() sx_xunlock(&snp_register_lock)
61#endif
62
63/*
64 * There is no need to have a big input buffer. In most typical setups,
65 * we won't inject much data into the TTY, because users can't type
66 * really fast.
67 */
68#define SNP_INPUT_BUFSIZE 16
69/*
70 * The output buffer has to be really big. Right now we don't support
71 * any form of flow control, which means we lost any data we can't
72 * accept. We set the output buffer size to about twice the size of a
73 * pseudo-terminal/virtual console's output buffer.
74 */
75#define SNP_OUTPUT_BUFSIZE 16384
76
77static d_open_t snp_open;
78static d_read_t snp_read;
79static d_write_t snp_write;
80static d_ioctl_t snp_ioctl;
81static d_poll_t snp_poll;
82
83static struct cdevsw snp_cdevsw = {
84 .d_version = D_VERSION,
85 .d_open = snp_open,
86 .d_read = snp_read,
87 .d_write = snp_write,
88 .d_ioctl = snp_ioctl,
89 .d_poll = snp_poll,
90 .d_name = "snp",
91};
92
93static th_getc_capture_t snp_getc_capture;
94
95static struct ttyhook snp_hook = {
96 .th_getc_capture = snp_getc_capture,
97};
98
99/*
100 * Per-instance structure.
101 *
102 * List of locks
103 * (r) locked by snp_register_lock on assignment
104 * (t) locked by tty_lock
105 */
106struct snp_softc {
107 struct tty *snp_tty; /* (r) TTY we're snooping. */
108 struct ttyoutq snp_outq; /* (t) Output queue. */
109 struct cv snp_outwait; /* (t) Output wait queue. */
110 struct selinfo snp_outpoll; /* (t) Output polling. */
111};
112
113static void
114snp_dtor(void *data)
115{
116 struct snp_softc *ss = data;
117 struct tty *tp;
118
119 tp = ss->snp_tty;
120 if (tp != NULL) {
121 tty_lock(tp);
122 ttyoutq_free(&ss->snp_outq);
123 ttyhook_unregister(tp);
124 }
125
126 cv_destroy(&ss->snp_outwait);
127 free(ss, M_SNP);
128}
129
130/*
131 * Snoop device node routines.
132 */
133
134static int
135snp_open(struct cdev *dev, int flag, int mode, struct thread *td)
136{
137 struct snp_softc *ss;
138
139 /* Allocate per-snoop data. */
140 ss = malloc(sizeof(struct snp_softc), M_SNP, M_WAITOK|M_ZERO);
141 cv_init(&ss->snp_outwait, "snp out");
142
143 devfs_set_cdevpriv(ss, snp_dtor);
144
145 return (0);
146}
147
148static int
149snp_read(struct cdev *dev, struct uio *uio, int flag)
150{
151 int error, oresid = uio->uio_resid;
152 struct snp_softc *ss;
153 struct tty *tp;
154
155 if (uio->uio_resid == 0)
156 return (0);
157
158 error = devfs_get_cdevpriv((void **)&ss);
159 if (error != 0)
160 return (error);
| 29
30#include <sys/param.h>
31#include <sys/conf.h>
32#include <sys/fcntl.h>
33#include <sys/filio.h>
34#include <sys/kernel.h>
35#include <sys/malloc.h>
36#include <sys/module.h>
37#include <sys/poll.h>
38#include <sys/proc.h>
39#include <sys/snoop.h>
40#include <sys/sx.h>
41#include <sys/systm.h>
42#include <sys/tty.h>
43#include <sys/uio.h>
44
45static struct cdev *snp_dev;
46static MALLOC_DEFINE(M_SNP, "snp", "tty snoop device");
47
48/* XXX: should be mtx, but TTY can be locked by Giant. */
49#if 0
50static struct mtx snp_register_lock;
51MTX_SYSINIT(snp_register_lock, &snp_register_lock,
52 "tty snoop registration", MTX_DEF);
53#define SNP_LOCK() mtx_lock(&snp_register_lock)
54#define SNP_UNLOCK() mtx_unlock(&snp_register_lock)
55#else
56static struct sx snp_register_lock;
57SX_SYSINIT(snp_register_lock, &snp_register_lock,
58 "tty snoop registration");
59#define SNP_LOCK() sx_xlock(&snp_register_lock)
60#define SNP_UNLOCK() sx_xunlock(&snp_register_lock)
61#endif
62
63/*
64 * There is no need to have a big input buffer. In most typical setups,
65 * we won't inject much data into the TTY, because users can't type
66 * really fast.
67 */
68#define SNP_INPUT_BUFSIZE 16
69/*
70 * The output buffer has to be really big. Right now we don't support
71 * any form of flow control, which means we lost any data we can't
72 * accept. We set the output buffer size to about twice the size of a
73 * pseudo-terminal/virtual console's output buffer.
74 */
75#define SNP_OUTPUT_BUFSIZE 16384
76
77static d_open_t snp_open;
78static d_read_t snp_read;
79static d_write_t snp_write;
80static d_ioctl_t snp_ioctl;
81static d_poll_t snp_poll;
82
83static struct cdevsw snp_cdevsw = {
84 .d_version = D_VERSION,
85 .d_open = snp_open,
86 .d_read = snp_read,
87 .d_write = snp_write,
88 .d_ioctl = snp_ioctl,
89 .d_poll = snp_poll,
90 .d_name = "snp",
91};
92
93static th_getc_capture_t snp_getc_capture;
94
95static struct ttyhook snp_hook = {
96 .th_getc_capture = snp_getc_capture,
97};
98
99/*
100 * Per-instance structure.
101 *
102 * List of locks
103 * (r) locked by snp_register_lock on assignment
104 * (t) locked by tty_lock
105 */
106struct snp_softc {
107 struct tty *snp_tty; /* (r) TTY we're snooping. */
108 struct ttyoutq snp_outq; /* (t) Output queue. */
109 struct cv snp_outwait; /* (t) Output wait queue. */
110 struct selinfo snp_outpoll; /* (t) Output polling. */
111};
112
113static void
114snp_dtor(void *data)
115{
116 struct snp_softc *ss = data;
117 struct tty *tp;
118
119 tp = ss->snp_tty;
120 if (tp != NULL) {
121 tty_lock(tp);
122 ttyoutq_free(&ss->snp_outq);
123 ttyhook_unregister(tp);
124 }
125
126 cv_destroy(&ss->snp_outwait);
127 free(ss, M_SNP);
128}
129
130/*
131 * Snoop device node routines.
132 */
133
134static int
135snp_open(struct cdev *dev, int flag, int mode, struct thread *td)
136{
137 struct snp_softc *ss;
138
139 /* Allocate per-snoop data. */
140 ss = malloc(sizeof(struct snp_softc), M_SNP, M_WAITOK|M_ZERO);
141 cv_init(&ss->snp_outwait, "snp out");
142
143 devfs_set_cdevpriv(ss, snp_dtor);
144
145 return (0);
146}
147
148static int
149snp_read(struct cdev *dev, struct uio *uio, int flag)
150{
151 int error, oresid = uio->uio_resid;
152 struct snp_softc *ss;
153 struct tty *tp;
154
155 if (uio->uio_resid == 0)
156 return (0);
157
158 error = devfs_get_cdevpriv((void **)&ss);
159 if (error != 0)
160 return (error);
|
161
| 161
|
162 tp = ss->snp_tty;
163 if (tp == NULL || tty_gone(tp))
164 return (EIO);
165
166 tty_lock(tp);
167 for (;;) {
168 error = ttyoutq_read_uio(&ss->snp_outq, tp, uio);
169 if (error != 0 || uio->uio_resid != oresid)
170 break;
171
172 /* Wait for more data. */
173 if (flag & O_NONBLOCK) {
174 error = EWOULDBLOCK;
175 break;
176 }
177 error = cv_wait_sig(&ss->snp_outwait, tp->t_mtx);
178 if (error != 0)
179 break;
180 if (tty_gone(tp)) {
181 error = EIO;
182 break;
183 }
184 }
185 tty_unlock(tp);
186
187 return (error);
188}
189
190static int
191snp_write(struct cdev *dev, struct uio *uio, int flag)
192{
193 struct snp_softc *ss;
194 struct tty *tp;
195 int error, len;
196 char in[SNP_INPUT_BUFSIZE];
197
198 error = devfs_get_cdevpriv((void **)&ss);
199 if (error != 0)
200 return (error);
| 162 tp = ss->snp_tty;
163 if (tp == NULL || tty_gone(tp))
164 return (EIO);
165
166 tty_lock(tp);
167 for (;;) {
168 error = ttyoutq_read_uio(&ss->snp_outq, tp, uio);
169 if (error != 0 || uio->uio_resid != oresid)
170 break;
171
172 /* Wait for more data. */
173 if (flag & O_NONBLOCK) {
174 error = EWOULDBLOCK;
175 break;
176 }
177 error = cv_wait_sig(&ss->snp_outwait, tp->t_mtx);
178 if (error != 0)
179 break;
180 if (tty_gone(tp)) {
181 error = EIO;
182 break;
183 }
184 }
185 tty_unlock(tp);
186
187 return (error);
188}
189
190static int
191snp_write(struct cdev *dev, struct uio *uio, int flag)
192{
193 struct snp_softc *ss;
194 struct tty *tp;
195 int error, len;
196 char in[SNP_INPUT_BUFSIZE];
197
198 error = devfs_get_cdevpriv((void **)&ss);
199 if (error != 0)
200 return (error);
|
201
| 201
|
202 tp = ss->snp_tty;
203 if (tp == NULL || tty_gone(tp))
204 return (EIO);
205
206 while (uio->uio_resid > 0) {
207 /* Read new data. */
208 len = imin(uio->uio_resid, sizeof in);
209 error = uiomove(in, len, uio);
210 if (error != 0)
211 return (error);
212
213 tty_lock(tp);
214
215 /* Driver could have abandoned the TTY in the mean time. */
216 if (tty_gone(tp)) {
217 tty_unlock(tp);
218 return (ENXIO);
219 }
220
221 /*
222 * Deliver data to the TTY. Ignore errors for now,
223 * because we shouldn't bail out when we're running
224 * close to the watermarks.
225 */
226 ttydisc_rint_simple(tp, in, len);
227 ttydisc_rint_done(tp);
228
229 tty_unlock(tp);
230 }
231
232 return (0);
233}
234
235static int
236snp_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags,
237 struct thread *td)
238{
239 struct snp_softc *ss;
240 struct tty *tp;
241 int error;
242
243 error = devfs_get_cdevpriv((void **)&ss);
244 if (error != 0)
245 return (error);
246
247 switch (cmd) {
248 case SNPSTTY:
249 /* Bind TTY to snoop instance. */
250 SNP_LOCK();
251 if (ss->snp_tty != NULL) {
252 SNP_UNLOCK();
253 return (EBUSY);
254 }
255 error = ttyhook_register(&ss->snp_tty, td->td_proc,
256 *(int *)data, &snp_hook, ss);
257 SNP_UNLOCK();
258 if (error != 0)
259 return (error);
260
261 /* Now that went okay, allocate a buffer for the queue. */
262 tp = ss->snp_tty;
263 tty_lock(tp);
264 ttyoutq_setsize(&ss->snp_outq, tp, SNP_OUTPUT_BUFSIZE);
265 tty_unlock(tp);
266
267 return (0);
268 case SNPGTTY:
269 /* Obtain device number of associated TTY. */
270 if (ss->snp_tty == NULL)
271 *(dev_t *)data = NODEV;
272 else
273 *(dev_t *)data = tty_udev(ss->snp_tty);
274 return (0);
275 case FIONREAD:
276 tp = ss->snp_tty;
277 if (tp != NULL) {
278 tty_lock(tp);
279 *(int *)data = ttyoutq_bytesused(&ss->snp_outq);
280 tty_unlock(tp);
281 } else {
282 *(int *)data = 0;
283 }
284 return (0);
285 default:
286 return (ENOTTY);
287 }
288}
289
290static int
291snp_poll(struct cdev *dev, int events, struct thread *td)
292{
293 struct snp_softc *ss;
294 struct tty *tp;
295 int revents;
296
297 if (devfs_get_cdevpriv((void **)&ss) != 0)
298 return (events &
299 (POLLHUP|POLLIN|POLLRDNORM|POLLOUT|POLLWRNORM));
300
301 revents = 0;
302
303 if (events & (POLLIN | POLLRDNORM)) {
304 tp = ss->snp_tty;
305 if (tp != NULL) {
306 tty_lock(tp);
307 if (ttyoutq_bytesused(&ss->snp_outq) > 0)
308 revents |= events & (POLLIN | POLLRDNORM);
309 tty_unlock(tp);
310 }
311 }
312
313 if (revents == 0)
314 selrecord(td, &ss->snp_outpoll);
315
316 return (revents);
317}
318
319/*
320 * TTY hook events.
321 */
322
323static int
324snp_modevent(module_t mod, int type, void *data)
325{
326
327 switch (type) {
328 case MOD_LOAD:
329 snp_dev = make_dev(&snp_cdevsw, 0,
330 UID_ROOT, GID_WHEEL, 0600, "snp");
331 return (0);
332 case MOD_UNLOAD:
333 /* XXX: Make existing users leave. */
334 destroy_dev(snp_dev);
335 return (0);
336 default:
337 return (EOPNOTSUPP);
338 }
339}
340
341static void
342snp_getc_capture(struct tty *tp, const void *buf, size_t len)
343{
344 struct snp_softc *ss = ttyhook_softc(tp);
345
346 ttyoutq_write(&ss->snp_outq, buf, len);
347
348 cv_broadcast(&ss->snp_outwait);
349 selwakeup(&ss->snp_outpoll);
350}
351
352static moduledata_t snp_mod = {
353 "snp",
354 snp_modevent,
355 NULL
356};
357
358DECLARE_MODULE(snp, snp_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE);
| 202 tp = ss->snp_tty;
203 if (tp == NULL || tty_gone(tp))
204 return (EIO);
205
206 while (uio->uio_resid > 0) {
207 /* Read new data. */
208 len = imin(uio->uio_resid, sizeof in);
209 error = uiomove(in, len, uio);
210 if (error != 0)
211 return (error);
212
213 tty_lock(tp);
214
215 /* Driver could have abandoned the TTY in the mean time. */
216 if (tty_gone(tp)) {
217 tty_unlock(tp);
218 return (ENXIO);
219 }
220
221 /*
222 * Deliver data to the TTY. Ignore errors for now,
223 * because we shouldn't bail out when we're running
224 * close to the watermarks.
225 */
226 ttydisc_rint_simple(tp, in, len);
227 ttydisc_rint_done(tp);
228
229 tty_unlock(tp);
230 }
231
232 return (0);
233}
234
235static int
236snp_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags,
237 struct thread *td)
238{
239 struct snp_softc *ss;
240 struct tty *tp;
241 int error;
242
243 error = devfs_get_cdevpriv((void **)&ss);
244 if (error != 0)
245 return (error);
246
247 switch (cmd) {
248 case SNPSTTY:
249 /* Bind TTY to snoop instance. */
250 SNP_LOCK();
251 if (ss->snp_tty != NULL) {
252 SNP_UNLOCK();
253 return (EBUSY);
254 }
255 error = ttyhook_register(&ss->snp_tty, td->td_proc,
256 *(int *)data, &snp_hook, ss);
257 SNP_UNLOCK();
258 if (error != 0)
259 return (error);
260
261 /* Now that went okay, allocate a buffer for the queue. */
262 tp = ss->snp_tty;
263 tty_lock(tp);
264 ttyoutq_setsize(&ss->snp_outq, tp, SNP_OUTPUT_BUFSIZE);
265 tty_unlock(tp);
266
267 return (0);
268 case SNPGTTY:
269 /* Obtain device number of associated TTY. */
270 if (ss->snp_tty == NULL)
271 *(dev_t *)data = NODEV;
272 else
273 *(dev_t *)data = tty_udev(ss->snp_tty);
274 return (0);
275 case FIONREAD:
276 tp = ss->snp_tty;
277 if (tp != NULL) {
278 tty_lock(tp);
279 *(int *)data = ttyoutq_bytesused(&ss->snp_outq);
280 tty_unlock(tp);
281 } else {
282 *(int *)data = 0;
283 }
284 return (0);
285 default:
286 return (ENOTTY);
287 }
288}
289
290static int
291snp_poll(struct cdev *dev, int events, struct thread *td)
292{
293 struct snp_softc *ss;
294 struct tty *tp;
295 int revents;
296
297 if (devfs_get_cdevpriv((void **)&ss) != 0)
298 return (events &
299 (POLLHUP|POLLIN|POLLRDNORM|POLLOUT|POLLWRNORM));
300
301 revents = 0;
302
303 if (events & (POLLIN | POLLRDNORM)) {
304 tp = ss->snp_tty;
305 if (tp != NULL) {
306 tty_lock(tp);
307 if (ttyoutq_bytesused(&ss->snp_outq) > 0)
308 revents |= events & (POLLIN | POLLRDNORM);
309 tty_unlock(tp);
310 }
311 }
312
313 if (revents == 0)
314 selrecord(td, &ss->snp_outpoll);
315
316 return (revents);
317}
318
319/*
320 * TTY hook events.
321 */
322
323static int
324snp_modevent(module_t mod, int type, void *data)
325{
326
327 switch (type) {
328 case MOD_LOAD:
329 snp_dev = make_dev(&snp_cdevsw, 0,
330 UID_ROOT, GID_WHEEL, 0600, "snp");
331 return (0);
332 case MOD_UNLOAD:
333 /* XXX: Make existing users leave. */
334 destroy_dev(snp_dev);
335 return (0);
336 default:
337 return (EOPNOTSUPP);
338 }
339}
340
341static void
342snp_getc_capture(struct tty *tp, const void *buf, size_t len)
343{
344 struct snp_softc *ss = ttyhook_softc(tp);
345
346 ttyoutq_write(&ss->snp_outq, buf, len);
347
348 cv_broadcast(&ss->snp_outwait);
349 selwakeup(&ss->snp_outpoll);
350}
351
352static moduledata_t snp_mod = {
353 "snp",
354 snp_modevent,
355 NULL
356};
357
358DECLARE_MODULE(snp, snp_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE);
|