1 /* $FreeBSD: src/sys/nfs4client/nfs4_dev.c,v 1.10 2008/10/23 15:53:51 des Exp $ */
2 /* $Id: nfs4_dev.c,v 1.10 2003/11/05 14:58:59 rees Exp $ */
3
4 /*-
5 * copyright (c) 2003
6 * the regents of the university of michigan
7 * all rights reserved
8 *
9 * permission is granted to use, copy, create derivative works and redistribute
10 * this software and such derivative works for any purpose, so long as the name
11 * of the university of michigan is not used in any advertising or publicity
12 * pertaining to the use or distribution of this software without specific,
13 * written prior authorization. if the above copyright notice or any other
14 * identification of the university of michigan is included in any copy of any
15 * portion of this software, then the disclaimer below must also be included.
16 *
17 * this software is provided as is, without representation from the university
18 * of michigan as to its fitness for any purpose, and without warranty by the
19 * university of michigan of any kind, either express or implied, including
20 * without limitation the implied warranties of merchantability and fitness for
21 * a particular purpose. the regents of the university of michigan shall not be
22 * liable for any damages, including special, indirect, incidental, or
23 * consequential damages, with respect to any claim arising out of or in
24 * connection with the use of the software, even if it has been or is hereafter
25 * advised of the possibility of such damages.
26 */
27
28 #include <sys/param.h>
29 #include <sys/conf.h>
30 #include <sys/queue.h>
31 #include <sys/malloc.h>
32 #include <sys/kernel.h>
33 #include <sys/poll.h>
34 #include <sys/mutex.h>
35 #include <sys/stat.h>
36 #include <sys/systm.h>
37 #include <sys/proc.h>
38 #include <sys/wait.h>
39 #include <sys/signalvar.h>
40
41 #include <nfs4client/nfs4_dev.h>
42
43 #ifdef NFS4DEVVERBOSE
44 #define NFS4DEV_DEBUG(X...) printf(X)
45 #else
46 #define NFS4DEV_DEBUG(X...)
47 #endif
48
49 #define NFS4DEV_NAME "nfs4"
50 #define CDEV_MINOR 1
51
52 MALLOC_DEFINE(M_NFS4DEV, "nfs4_dev", "NFS4 device");
53
54 struct nfs4dev_upcall {
55 /* request msg */
56 struct nfs4dev_msg up_reqmsg;
57 size_t up_reqmsglen;
58
59 /* reply (payload only) */
60 caddr_t up_rep;
61 size_t * up_replen;
62
63 int up_copied; /* non-zero when reply has been copied to
64 '*up_rep' */
65
66 int up_error; /* non-zero if an error occured */
67
68 TAILQ_ENTRY(nfs4dev_upcall) up_entry;
69 };
70
71
72 #define nfs4dev_upcall_get(MP) (MP) = malloc(sizeof(struct nfs4dev_upcall), M_NFS4DEV, M_WAITOK | M_ZERO)
73
74 #define nfs4dev_upcall_put(MP) free((MP), M_NFS4DEV)
75
76 static int nfs4dev_nopen = 0;
77 static struct thread * nfs4dev_reader = NULL;
78 static struct cdev *nfs4device = 0;
79 static struct mtx nfs4dev_daemon_mtx;
80
81 static int nfs4dev_xid = 0;
82 /* queue of pending upcalls */
83 TAILQ_HEAD(, nfs4dev_upcall) nfs4dev_newq;
84 static struct mtx nfs4dev_newq_mtx;
85
86 /* queue of upcalls waiting for replys */
87 TAILQ_HEAD(, nfs4dev_upcall) nfs4dev_waitq;
88 static struct mtx nfs4dev_waitq_mtx;
89
90 /* dev hooks */
91 static d_open_t nfs4dev_open;
92 static d_close_t nfs4dev_close;
93 static d_ioctl_t nfs4dev_ioctl;
94 static d_poll_t nfs4dev_poll;
95
96 static struct cdevsw nfs4dev_cdevsw = {
97 #if (__FreeBSD_version > 502102)
98 .d_version = D_VERSION,
99 .d_flags = D_NEEDGIANT,
100 #endif
101 .d_open = nfs4dev_open,
102 .d_close = nfs4dev_close,
103 .d_ioctl = nfs4dev_ioctl,
104 .d_poll = nfs4dev_poll,
105 .d_name = NFS4DEV_NAME,
106 };
107
108 static int nfs4dev_reply(caddr_t);
109 static int nfs4dev_request(caddr_t);
110
111 /* Userland requests a new operation to service */
112 static int
113 nfs4dev_request(caddr_t addr)
114 {
115 struct nfs4dev_upcall * u;
116 struct nfs4dev_msg * m = (struct nfs4dev_msg *) addr;
117
118 mtx_lock(&nfs4dev_newq_mtx);
119
120 if (TAILQ_EMPTY(&nfs4dev_newq)) {
121 mtx_unlock(&nfs4dev_newq_mtx);
122 return EAGAIN;
123 }
124
125 u = TAILQ_FIRST(&nfs4dev_newq);
126 TAILQ_REMOVE(&nfs4dev_newq, u, up_entry);
127 mtx_unlock(&nfs4dev_newq_mtx);
128
129 bcopy(&u->up_reqmsg, m, sizeof(struct nfs4dev_msg));
130
131 mtx_lock(&nfs4dev_waitq_mtx);
132 TAILQ_INSERT_TAIL(&nfs4dev_waitq, u, up_entry);
133 mtx_unlock(&nfs4dev_waitq_mtx);
134
135 return 0;
136 }
137
138 static int
139 nfs4dev_reply(caddr_t addr)
140 {
141 struct nfs4dev_upcall * u;
142 struct nfs4dev_msg * m = (struct nfs4dev_msg *) addr;
143 int error;
144
145 if (m->msg_vers != NFS4DEV_VERSION) {
146 printf("nfs4dev version mismatch\n");
147 return EINVAL;
148 }
149
150 if (m->msg_type > NFS4DEV_MAX_TYPE) {
151 NFS4DEV_DEBUG("nfs4dev: unsupported message type\n");
152 return EINVAL;
153 }
154
155 if (m->msg_len < sizeof(*m) - NFS4DEV_MSG_MAX_DATALEN ||
156 m->msg_len > NFS4DEV_MSG_MAX_DATALEN) {
157 NFS4DEV_DEBUG("bad message length\n");
158 return EINVAL;
159 }
160
161 /* match the reply with a request */
162 mtx_lock(&nfs4dev_waitq_mtx);
163 TAILQ_FOREACH(u, &nfs4dev_waitq, up_entry) {
164 if (m->msg_xid == u->up_reqmsg.msg_xid) {
165 if (m->msg_type == u->up_reqmsg.msg_type)
166 goto found;
167 NFS4DEV_DEBUG("nfs4dev: op type mismatch!\n");
168 break;
169 }
170 }
171 mtx_unlock(&nfs4dev_waitq_mtx);
172
173 NFS4DEV_DEBUG("nfs4dev msg op: %d xid: %x not found.\n",
174 m->msg_type, m->msg_xid);
175
176 error = EIO;
177 goto bad;
178
179 found:
180 TAILQ_REMOVE(&nfs4dev_waitq, u, up_entry);
181 mtx_unlock(&nfs4dev_waitq_mtx);
182
183 if (m->msg_error) {
184 error = m->msg_error;
185 goto bad;
186 }
187
188 if (m->msg_len > *u->up_replen) {
189 error = EFAULT;
190 goto bad;
191 }
192
193 bcopy(m->msg_data, u->up_rep, m->msg_len);
194 *u->up_replen = m->msg_len;
195
196 u->up_copied = m->msg_len;
197 wakeup(u);
198
199 return 0;
200 bad:
201 if (u) {
202 u->up_error = error;
203 wakeup(u);
204 }
205 return error;
206 }
207
208 void
209 nfs4dev_init(void)
210 {
211 nfs4dev_xid = arc4random();
212 TAILQ_INIT(&nfs4dev_newq);
213 TAILQ_INIT(&nfs4dev_waitq);
214 mtx_init(&nfs4dev_newq_mtx, "nfs4dev newq", NULL, MTX_DEF);
215 mtx_init(&nfs4dev_waitq_mtx, "nfs4dev waitq", NULL, MTX_DEF);
216
217 mtx_init(&nfs4dev_daemon_mtx, "nfs4dev state", NULL, MTX_DEF);
218
219 nfs4device = make_dev(&nfs4dev_cdevsw, CDEV_MINOR, (uid_t)0, (gid_t)0,
220 S_IRUSR | S_IWUSR, "nfs4");
221 }
222
223 void
224 nfs4dev_uninit(void)
225 {
226 struct proc * dead = NULL;
227
228 mtx_lock(&nfs4dev_daemon_mtx);
229 if (nfs4dev_nopen) {
230 if (nfs4dev_reader == NULL) {
231 NFS4DEV_DEBUG("nfs4dev uninit(): unregistered reader\n");
232 } else {
233 dead = nfs4dev_reader->td_proc;
234 }
235 }
236 mtx_unlock(&nfs4dev_daemon_mtx);
237
238 if (dead != NULL) {
239 NFS4DEV_DEBUG("nfs4dev_uninit(): you forgot to kill attached daemon (pid: %u)\n",
240 dead->p_pid);
241 PROC_LOCK(dead);
242 psignal(dead, SIGTERM);
243 PROC_UNLOCK(dead);
244 }
245
246 /* XXX moot? */
247 nfs4dev_purge();
248
249 mtx_destroy(&nfs4dev_newq_mtx);
250 mtx_destroy(&nfs4dev_waitq_mtx);
251 mtx_destroy(&nfs4dev_daemon_mtx);
252
253 destroy_dev(nfs4device);
254 }
255
256 /* device interface functions */
257 static int
258 nfs4dev_open(struct cdev *dev, int flags, int fmt, d_thread_t *td)
259 {
260 if (dev != nfs4device)
261 return ENODEV;
262
263 mtx_lock(&nfs4dev_daemon_mtx);
264 if (nfs4dev_nopen) {
265 mtx_unlock(&nfs4dev_daemon_mtx);
266 return EBUSY;
267 }
268
269 nfs4dev_nopen++;
270 nfs4dev_reader = curthread;
271 mtx_unlock(&nfs4dev_daemon_mtx);
272
273 return (0);
274 }
275
276 static int
277 nfs4dev_close(struct cdev *dev, int flags, int fmt, d_thread_t *td)
278 {
279 struct nfs4dev_upcall * u;
280
281 if (dev != nfs4device)
282 return ENODEV;
283
284 mtx_lock(&nfs4dev_daemon_mtx);
285 if (!nfs4dev_nopen) {
286 mtx_unlock(&nfs4dev_daemon_mtx);
287 return ENOENT;
288 }
289
290 nfs4dev_nopen--;
291 nfs4dev_reader = NULL;
292 mtx_unlock(&nfs4dev_daemon_mtx);
293
294 mtx_lock(&nfs4dev_waitq_mtx);
295
296 while (!TAILQ_EMPTY(&nfs4dev_waitq)) {
297 u = TAILQ_FIRST(&nfs4dev_waitq);
298 TAILQ_REMOVE(&nfs4dev_waitq, u, up_entry);
299 u->up_error = EINTR;
300 wakeup(u);
301 }
302
303 mtx_unlock(&nfs4dev_waitq_mtx);
304
305 return 0;
306 }
307
308 static int
309 nfs4dev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
310 {
311 int error;
312
313 if (dev != nfs4device)
314 return ENODEV;
315
316 if (data == NULL)
317 return EFAULT;
318
319 if (nfs4dev_reader != curthread)
320 nfs4dev_reader = curthread;
321
322 switch (cmd) {
323 case NFS4DEVIOCGET:
324 error = nfs4dev_request(data);
325 break;
326 case NFS4DEVIOCPUT:
327 error = nfs4dev_reply(data);
328 break;
329 default:
330 NFS4DEV_DEBUG("nfs4dev_ioctl: unkown ioctl cmd %d\n", (int)cmd);
331 error = EOPNOTSUPP;
332 break;
333 }
334
335 return error;
336 }
337
338 static int
339 nfs4dev_poll(struct cdev *dev, int events, struct thread *td)
340 {
341 int revents;
342
343 if (dev != nfs4device)
344 return EINVAL;
345
346 mtx_lock(&nfs4dev_daemon_mtx);
347 if (nfs4dev_nopen == 0) {
348 mtx_unlock(&nfs4dev_daemon_mtx);
349 return 0;
350 }
351 mtx_unlock(&nfs4dev_daemon_mtx);
352
353 revents = 0;
354
355 /* check readable data */
356 mtx_lock(&nfs4dev_newq_mtx);
357 if (!TAILQ_EMPTY(&nfs4dev_newq))
358 revents |= POLLIN;
359 mtx_unlock(&nfs4dev_newq_mtx);
360
361 mtx_lock(&nfs4dev_waitq_mtx);
362 if (!TAILQ_EMPTY(&nfs4dev_waitq))
363 revents |= POLLOUT;
364 mtx_unlock(&nfs4dev_waitq_mtx);
365
366 return revents;
367 }
368
369 int
370 nfs4dev_call(uint32_t type, caddr_t req_data, size_t req_len, caddr_t rep_data, size_t * rep_lenp)
371 {
372 struct nfs4dev_upcall * u;
373 int error = 0;
374 unsigned int xtmp;
375
376 mtx_lock(&nfs4dev_daemon_mtx);
377 if (nfs4dev_nopen == 0) {
378 mtx_unlock(&nfs4dev_daemon_mtx);
379 return EINVAL;
380 }
381 mtx_unlock(&nfs4dev_daemon_mtx);
382
383 if (type > NFS4DEV_MAX_TYPE)
384 return EOPNOTSUPP;
385
386 NFS4DEV_DEBUG("upcall %d/%d:%d\n", type, req_len, *rep_lenp);
387
388 nfs4dev_upcall_get(u);
389
390 u->up_error = 0;
391 u->up_rep = rep_data;
392 u->up_replen = rep_lenp;
393 u->up_copied = 0;
394
395 u->up_reqmsg.msg_vers = NFS4DEV_VERSION;
396 /* XXX efficient copying */
397 bcopy(req_data, u->up_reqmsg.msg_data, req_len);
398 u->up_reqmsg.msg_len = req_len;
399
400 mtx_lock(&nfs4dev_newq_mtx);
401
402 /* get new XID */
403 while ((xtmp = arc4random() % 256) == 0);
404 nfs4dev_xid += xtmp;
405 u->up_reqmsg.msg_xid = nfs4dev_xid;
406
407 TAILQ_INSERT_TAIL(&nfs4dev_newq, u, up_entry);
408 mtx_unlock(&nfs4dev_newq_mtx);
409
410
411 NFS4DEV_DEBUG("nfs4dev op: %d xid: %x sleeping\n", u->up_reqmsg.msg_type, u->up_reqmsg.msg_xid);
412
413 do {
414 tsleep(u, PLOCK, "nfs4dev", 0);
415 } while (u->up_copied == 0 && u->up_error == 0);
416
417 /* upcall now removed from the queue */
418
419 NFS4DEV_DEBUG("nfs4dev prog: %d xid: %x continues...\n",
420 u->up_reqmsg.msg_type, u->up_reqmsg.msg_xid);
421
422 if (u->up_error) {
423 error = u->up_error;
424 NFS4DEV_DEBUG("nfs4dev prog: %d xid: %x error: %d\n",
425 u->up_reqmsg.msg_type, u->up_reqmsg.msg_xid, u->up_error);
426 goto out;
427 }
428
429 out:
430 nfs4dev_upcall_put(u);
431 return error;
432 }
433
434 void
435 nfs4dev_purge(void)
436 {
437 struct nfs4dev_upcall * u;
438
439 mtx_lock(&nfs4dev_newq_mtx);
440 while (!TAILQ_EMPTY(&nfs4dev_newq)) {
441 u = TAILQ_FIRST(&nfs4dev_newq);
442 TAILQ_REMOVE(&nfs4dev_newq, u, up_entry);
443 u->up_error = EINTR;
444 wakeup(u);
445 }
446 mtx_unlock(&nfs4dev_newq_mtx);
447
448 mtx_lock(&nfs4dev_waitq_mtx);
449 while (!TAILQ_EMPTY(&nfs4dev_waitq)) {
450 u = TAILQ_FIRST(&nfs4dev_waitq);
451 TAILQ_REMOVE(&nfs4dev_waitq, u, up_entry);
452 u->up_error = EINTR;
453 wakeup(u);
454 }
455 mtx_unlock(&nfs4dev_waitq_mtx);
456 }
457
|