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Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6
[linux-2.6/linux-2.6-openrd.git] / net / 9p / trans_fd.c
blob31d0b05582a970e9c35b5e01e7d90d36ac25fd6b
1 /*
2 * linux/fs/9p/trans_fd.c
3 *
4 * Fd transport layer. Includes deprecated socket layer.
5 *
6 * Copyright (C) 2006 by Russ Cox <rsc@swtch.com>
7 * Copyright (C) 2004-2005 by Latchesar Ionkov <lucho@ionkov.net>
8 * Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com>
9 * Copyright (C) 1997-2002 by Ron Minnich <rminnich@sarnoff.com>
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2
13 * as published by the Free Software Foundation.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to:
22 * Free Software Foundation
23 * 51 Franklin Street, Fifth Floor
24 * Boston, MA 02111-1301 USA
25 *
26 */
27
28 #include <linux/in.h>
29 #include <linux/module.h>
30 #include <linux/net.h>
31 #include <linux/ipv6.h>
32 #include <linux/kthread.h>
33 #include <linux/errno.h>
34 #include <linux/kernel.h>
35 #include <linux/un.h>
36 #include <linux/uaccess.h>
37 #include <linux/inet.h>
38 #include <linux/idr.h>
39 #include <linux/file.h>
40 #include <linux/parser.h>
41 #include <net/9p/9p.h>
42 #include <net/9p/client.h>
43 #include <net/9p/transport.h>
44
45 #include <linux/syscalls.h> /* killme */
46
47 #define P9_PORT 564
48 #define MAX_SOCK_BUF (64*1024)
49 #define MAXPOLLWADDR 2
50
51 /**
52 * struct p9_fd_opts - per-transport options
53 * @rfd: file descriptor for reading (trans=fd)
54 * @wfd: file descriptor for writing (trans=fd)
55 * @port: port to connect to (trans=tcp)
56 *
57 */
58
59 struct p9_fd_opts {
60 int rfd;
61 int wfd;
62 u16 port;
63 };
64
65 /**
66 * struct p9_trans_fd - transport state
67 * @rd: reference to file to read from
68 * @wr: reference of file to write to
69 * @conn: connection state reference
70 *
71 */
72
73 struct p9_trans_fd {
74 struct file *rd;
75 struct file *wr;
76 struct p9_conn *conn;
77 };
78
79 /*
80 * Option Parsing (code inspired by NFS code)
81 * - a little lazy - parse all fd-transport options
82 */
83
84 enum {
85 /* Options that take integer arguments */
86 Opt_port, Opt_rfdno, Opt_wfdno, Opt_err,
87 };
88
89 static const match_table_t tokens = {
90 {Opt_port, "port=%u"},
91 {Opt_rfdno, "rfdno=%u"},
92 {Opt_wfdno, "wfdno=%u"},
93 {Opt_err, NULL},
94 };
95
96 enum {
97 Rworksched = 1, /* read work scheduled or running */
98 Rpending = 2, /* can read */
99 Wworksched = 4, /* write work scheduled or running */
100 Wpending = 8, /* can write */
101 };
102
103 struct p9_poll_wait {
104 struct p9_conn *conn;
105 wait_queue_t wait;
106 wait_queue_head_t *wait_addr;
107 };
108
109 /**
110 * struct p9_conn - fd mux connection state information
111 * @mux_list: list link for mux to manage multiple connections (?)
112 * @client: reference to client instance for this connection
113 * @err: error state
114 * @req_list: accounting for requests which have been sent
115 * @unsent_req_list: accounting for requests that haven't been sent
116 * @req: current request being processed (if any)
117 * @tmp_buf: temporary buffer to read in header
118 * @rsize: amount to read for current frame
119 * @rpos: read position in current frame
120 * @rbuf: current read buffer
121 * @wpos: write position for current frame
122 * @wsize: amount of data to write for current frame
123 * @wbuf: current write buffer
124 * @poll_pending_link: pending links to be polled per conn
125 * @poll_wait: array of wait_q's for various worker threads
126 * @pt: poll state
127 * @rq: current read work
128 * @wq: current write work
129 * @wsched: ????
130 *
131 */
132
133 struct p9_conn {
134 struct list_head mux_list;
135 struct p9_client *client;
136 int err;
137 struct list_head req_list;
138 struct list_head unsent_req_list;
139 struct p9_req_t *req;
140 char tmp_buf[7];
141 int rsize;
142 int rpos;
143 char *rbuf;
144 int wpos;
145 int wsize;
146 char *wbuf;
147 struct list_head poll_pending_link;
148 struct p9_poll_wait poll_wait[MAXPOLLWADDR];
149 poll_table pt;
150 struct work_struct rq;
151 struct work_struct wq;
152 unsigned long wsched;
153 };
154
155 static DEFINE_SPINLOCK(p9_poll_lock);
156 static LIST_HEAD(p9_poll_pending_list);
157 static struct workqueue_struct *p9_mux_wq;
158 static struct task_struct *p9_poll_task;
159
160 static void p9_mux_poll_stop(struct p9_conn *m)
161 {
162 unsigned long flags;
163 int i;
164
165 for (i = 0; i < ARRAY_SIZE(m->poll_wait); i++) {
166 struct p9_poll_wait *pwait = &m->poll_wait[i];
167
168 if (pwait->wait_addr) {
169 remove_wait_queue(pwait->wait_addr, &pwait->wait);
170 pwait->wait_addr = NULL;
171 }
172 }
173
174 spin_lock_irqsave(&p9_poll_lock, flags);
175 list_del_init(&m->poll_pending_link);
176 spin_unlock_irqrestore(&p9_poll_lock, flags);
177 }
178
179 /**
180 * p9_conn_cancel - cancel all pending requests with error
181 * @m: mux data
182 * @err: error code
183 *
184 */
185
186 static void p9_conn_cancel(struct p9_conn *m, int err)
187 {
188 struct p9_req_t *req, *rtmp;
189 unsigned long flags;
190 LIST_HEAD(cancel_list);
191
192 P9_DPRINTK(P9_DEBUG_ERROR, "mux %p err %d\n", m, err);
193
194 spin_lock_irqsave(&m->client->lock, flags);
195
196 if (m->err) {
197 spin_unlock_irqrestore(&m->client->lock, flags);
198 return;
199 }
200
201 m->err = err;
202
203 list_for_each_entry_safe(req, rtmp, &m->req_list, req_list) {
204 req->status = REQ_STATUS_ERROR;
205 if (!req->t_err)
206 req->t_err = err;
207 list_move(&req->req_list, &cancel_list);
208 }
209 list_for_each_entry_safe(req, rtmp, &m->unsent_req_list, req_list) {
210 req->status = REQ_STATUS_ERROR;
211 if (!req->t_err)
212 req->t_err = err;
213 list_move(&req->req_list, &cancel_list);
214 }
215 spin_unlock_irqrestore(&m->client->lock, flags);
216
217 list_for_each_entry_safe(req, rtmp, &cancel_list, req_list) {
218 P9_DPRINTK(P9_DEBUG_ERROR, "call back req %p\n", req);
219 list_del(&req->req_list);
220 p9_client_cb(m->client, req);
221 }
222 }
223
224 static unsigned int
225 p9_fd_poll(struct p9_client *client, struct poll_table_struct *pt)
226 {
227 int ret, n;
228 struct p9_trans_fd *ts = NULL;
229
230 if (client && client->status == Connected)
231 ts = client->trans;
232
233 if (!ts)
234 return -EREMOTEIO;
235
236 if (!ts->rd->f_op || !ts->rd->f_op->poll)
237 return -EIO;
238
239 if (!ts->wr->f_op || !ts->wr->f_op->poll)
240 return -EIO;
241
242 ret = ts->rd->f_op->poll(ts->rd, pt);
243 if (ret < 0)
244 return ret;
245
246 if (ts->rd != ts->wr) {
247 n = ts->wr->f_op->poll(ts->wr, pt);
248 if (n < 0)
249 return n;
250 ret = (ret & ~POLLOUT) | (n & ~POLLIN);
251 }
252
253 return ret;
254 }
255
256 /**
257 * p9_fd_read- read from a fd
258 * @client: client instance
259 * @v: buffer to receive data into
260 * @len: size of receive buffer
261 *
262 */
263
264 static int p9_fd_read(struct p9_client *client, void *v, int len)
265 {
266 int ret;
267 struct p9_trans_fd *ts = NULL;
268
269 if (client && client->status != Disconnected)
270 ts = client->trans;
271
272 if (!ts)
273 return -EREMOTEIO;
274
275 if (!(ts->rd->f_flags & O_NONBLOCK))
276 P9_DPRINTK(P9_DEBUG_ERROR, "blocking read ...\n");
277
278 ret = kernel_read(ts->rd, ts->rd->f_pos, v, len);
279 if (ret <= 0 && ret != -ERESTARTSYS && ret != -EAGAIN)
280 client->status = Disconnected;
281 return ret;
282 }
283
284 /**
285 * p9_read_work - called when there is some data to be read from a transport
286 * @work: container of work to be done
287 *
288 */
289
290 static void p9_read_work(struct work_struct *work)
291 {
292 int n, err;
293 struct p9_conn *m;
294
295 m = container_of(work, struct p9_conn, rq);
296
297 if (m->err < 0)
298 return;
299
300 P9_DPRINTK(P9_DEBUG_TRANS, "start mux %p pos %d\n", m, m->rpos);
301
302 if (!m->rbuf) {
303 m->rbuf = m->tmp_buf;
304 m->rpos = 0;
305 m->rsize = 7; /* start by reading header */
306 }
307
308 clear_bit(Rpending, &m->wsched);
309 P9_DPRINTK(P9_DEBUG_TRANS, "read mux %p pos %d size: %d = %d\n", m,
310 m->rpos, m->rsize, m->rsize-m->rpos);
311 err = p9_fd_read(m->client, m->rbuf + m->rpos,
312 m->rsize - m->rpos);
313 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p got %d bytes\n", m, err);
314 if (err == -EAGAIN) {
315 clear_bit(Rworksched, &m->wsched);
316 return;
317 }
318
319 if (err <= 0)
320 goto error;
321
322 m->rpos += err;
323
324 if ((!m->req) && (m->rpos == m->rsize)) { /* header read in */
325 u16 tag;
326 P9_DPRINTK(P9_DEBUG_TRANS, "got new header\n");
327
328 n = le32_to_cpu(*(__le32 *) m->rbuf); /* read packet size */
329 if (n >= m->client->msize) {
330 P9_DPRINTK(P9_DEBUG_ERROR,
331 "requested packet size too big: %d\n", n);
332 err = -EIO;
333 goto error;
334 }
335
336 tag = le16_to_cpu(*(__le16 *) (m->rbuf+5)); /* read tag */
337 P9_DPRINTK(P9_DEBUG_TRANS,
338 "mux %p pkt: size: %d bytes tag: %d\n", m, n, tag);
339
340 m->req = p9_tag_lookup(m->client, tag);
341 if (!m->req || (m->req->status != REQ_STATUS_SENT &&
342 m->req->status != REQ_STATUS_FLSH)) {
343 P9_DPRINTK(P9_DEBUG_ERROR, "Unexpected packet tag %d\n",
344 tag);
345 err = -EIO;
346 goto error;
347 }
348
349 if (m->req->rc == NULL) {
350 m->req->rc = kmalloc(sizeof(struct p9_fcall) +
351 m->client->msize, GFP_KERNEL);
352 if (!m->req->rc) {
353 m->req = NULL;
354 err = -ENOMEM;
355 goto error;
356 }
357 }
358 m->rbuf = (char *)m->req->rc + sizeof(struct p9_fcall);
359 memcpy(m->rbuf, m->tmp_buf, m->rsize);
360 m->rsize = n;
361 }
362
363 /* not an else because some packets (like clunk) have no payload */
364 if ((m->req) && (m->rpos == m->rsize)) { /* packet is read in */
365 P9_DPRINTK(P9_DEBUG_TRANS, "got new packet\n");
366 spin_lock(&m->client->lock);
367 if (m->req->status != REQ_STATUS_ERROR)
368 m->req->status = REQ_STATUS_RCVD;
369 list_del(&m->req->req_list);
370 spin_unlock(&m->client->lock);
371 p9_client_cb(m->client, m->req);
372 m->rbuf = NULL;
373 m->rpos = 0;
374 m->rsize = 0;
375 m->req = NULL;
376 }
377
378 if (!list_empty(&m->req_list)) {
379 if (test_and_clear_bit(Rpending, &m->wsched))
380 n = POLLIN;
381 else
382 n = p9_fd_poll(m->client, NULL);
383
384 if (n & POLLIN) {
385 P9_DPRINTK(P9_DEBUG_TRANS, "sched read work %p\n", m);
386 queue_work(p9_mux_wq, &m->rq);
387 } else
388 clear_bit(Rworksched, &m->wsched);
389 } else
390 clear_bit(Rworksched, &m->wsched);
391
392 return;
393 error:
394 p9_conn_cancel(m, err);
395 clear_bit(Rworksched, &m->wsched);
396 }
397
398 /**
399 * p9_fd_write - write to a socket
400 * @client: client instance
401 * @v: buffer to send data from
402 * @len: size of send buffer
403 *
404 */
405
406 static int p9_fd_write(struct p9_client *client, void *v, int len)
407 {
408 int ret;
409 mm_segment_t oldfs;
410 struct p9_trans_fd *ts = NULL;
411
412 if (client && client->status != Disconnected)
413 ts = client->trans;
414
415 if (!ts)
416 return -EREMOTEIO;
417
418 if (!(ts->wr->f_flags & O_NONBLOCK))
419 P9_DPRINTK(P9_DEBUG_ERROR, "blocking write ...\n");
420
421 oldfs = get_fs();
422 set_fs(get_ds());
423 /* The cast to a user pointer is valid due to the set_fs() */
424 ret = vfs_write(ts->wr, (__force void __user *)v, len, &ts->wr->f_pos);
425 set_fs(oldfs);
426
427 if (ret <= 0 && ret != -ERESTARTSYS && ret != -EAGAIN)
428 client->status = Disconnected;
429 return ret;
430 }
431
432 /**
433 * p9_write_work - called when a transport can send some data
434 * @work: container for work to be done
435 *
436 */
437
438 static void p9_write_work(struct work_struct *work)
439 {
440 int n, err;
441 struct p9_conn *m;
442 struct p9_req_t *req;
443
444 m = container_of(work, struct p9_conn, wq);
445
446 if (m->err < 0) {
447 clear_bit(Wworksched, &m->wsched);
448 return;
449 }
450
451 if (!m->wsize) {
452 if (list_empty(&m->unsent_req_list)) {
453 clear_bit(Wworksched, &m->wsched);
454 return;
455 }
456
457 spin_lock(&m->client->lock);
458 req = list_entry(m->unsent_req_list.next, struct p9_req_t,
459 req_list);
460 req->status = REQ_STATUS_SENT;
461 P9_DPRINTK(P9_DEBUG_TRANS, "move req %p\n", req);
462 list_move_tail(&req->req_list, &m->req_list);
463
464 m->wbuf = req->tc->sdata;
465 m->wsize = req->tc->size;
466 m->wpos = 0;
467 spin_unlock(&m->client->lock);
468 }
469
470 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p pos %d size %d\n", m, m->wpos,
471 m->wsize);
472 clear_bit(Wpending, &m->wsched);
473 err = p9_fd_write(m->client, m->wbuf + m->wpos, m->wsize - m->wpos);
474 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p sent %d bytes\n", m, err);
475 if (err == -EAGAIN) {
476 clear_bit(Wworksched, &m->wsched);
477 return;
478 }
479
480 if (err < 0)
481 goto error;
482 else if (err == 0) {
483 err = -EREMOTEIO;
484 goto error;
485 }
486
487 m->wpos += err;
488 if (m->wpos == m->wsize)
489 m->wpos = m->wsize = 0;
490
491 if (m->wsize == 0 && !list_empty(&m->unsent_req_list)) {
492 if (test_and_clear_bit(Wpending, &m->wsched))
493 n = POLLOUT;
494 else
495 n = p9_fd_poll(m->client, NULL);
496
497 if (n & POLLOUT) {
498 P9_DPRINTK(P9_DEBUG_TRANS, "sched write work %p\n", m);
499 queue_work(p9_mux_wq, &m->wq);
500 } else
501 clear_bit(Wworksched, &m->wsched);
502 } else
503 clear_bit(Wworksched, &m->wsched);
504
505 return;
506
507 error:
508 p9_conn_cancel(m, err);
509 clear_bit(Wworksched, &m->wsched);
510 }
511
512 static int p9_pollwake(wait_queue_t *wait, unsigned mode, int sync, void *key)
513 {
514 struct p9_poll_wait *pwait =
515 container_of(wait, struct p9_poll_wait, wait);
516 struct p9_conn *m = pwait->conn;
517 unsigned long flags;
518 DECLARE_WAITQUEUE(dummy_wait, p9_poll_task);
519
520 spin_lock_irqsave(&p9_poll_lock, flags);
521 if (list_empty(&m->poll_pending_link))
522 list_add_tail(&m->poll_pending_link, &p9_poll_pending_list);
523 spin_unlock_irqrestore(&p9_poll_lock, flags);
524
525 /* perform the default wake up operation */
526 return default_wake_function(&dummy_wait, mode, sync, key);
527 }
528
529 /**
530 * p9_pollwait - add poll task to the wait queue
531 * @filp: file pointer being polled
532 * @wait_address: wait_q to block on
533 * @p: poll state
534 *
535 * called by files poll operation to add v9fs-poll task to files wait queue
536 */
537
538 static void
539 p9_pollwait(struct file *filp, wait_queue_head_t *wait_address, poll_table *p)
540 {
541 struct p9_conn *m = container_of(p, struct p9_conn, pt);
542 struct p9_poll_wait *pwait = NULL;
543 int i;
544
545 for (i = 0; i < ARRAY_SIZE(m->poll_wait); i++) {
546 if (m->poll_wait[i].wait_addr == NULL) {
547 pwait = &m->poll_wait[i];
548 break;
549 }
550 }
551
552 if (!pwait) {
553 P9_DPRINTK(P9_DEBUG_ERROR, "not enough wait_address slots\n");
554 return;
555 }
556
557 pwait->conn = m;
558 pwait->wait_addr = wait_address;
559 init_waitqueue_func_entry(&pwait->wait, p9_pollwake);
560 add_wait_queue(wait_address, &pwait->wait);
561 }
562
563 /**
564 * p9_conn_create - allocate and initialize the per-session mux data
565 * @client: client instance
566 *
567 * Note: Creates the polling task if this is the first session.
568 */
569
570 static struct p9_conn *p9_conn_create(struct p9_client *client)
571 {
572 int n;
573 struct p9_conn *m;
574
575 P9_DPRINTK(P9_DEBUG_TRANS, "client %p msize %d\n", client,
576 client->msize);
577 m = kzalloc(sizeof(struct p9_conn), GFP_KERNEL);
578 if (!m)
579 return ERR_PTR(-ENOMEM);
580
581 INIT_LIST_HEAD(&m->mux_list);
582 m->client = client;
583
584 INIT_LIST_HEAD(&m->req_list);
585 INIT_LIST_HEAD(&m->unsent_req_list);
586 INIT_WORK(&m->rq, p9_read_work);
587 INIT_WORK(&m->wq, p9_write_work);
588 INIT_LIST_HEAD(&m->poll_pending_link);
589 init_poll_funcptr(&m->pt, p9_pollwait);
590
591 n = p9_fd_poll(client, &m->pt);
592 if (n & POLLIN) {
593 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p can read\n", m);
594 set_bit(Rpending, &m->wsched);
595 }
596
597 if (n & POLLOUT) {
598 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p can write\n", m);
599 set_bit(Wpending, &m->wsched);
600 }
601
602 return m;
603 }
604
605 /**
606 * p9_poll_mux - polls a mux and schedules read or write works if necessary
607 * @m: connection to poll
608 *
609 */
610
611 static void p9_poll_mux(struct p9_conn *m)
612 {
613 int n;
614
615 if (m->err < 0)
616 return;
617
618 n = p9_fd_poll(m->client, NULL);
619 if (n < 0 || n & (POLLERR | POLLHUP | POLLNVAL)) {
620 P9_DPRINTK(P9_DEBUG_TRANS, "error mux %p err %d\n", m, n);
621 if (n >= 0)
622 n = -ECONNRESET;
623 p9_conn_cancel(m, n);
624 }
625
626 if (n & POLLIN) {
627 set_bit(Rpending, &m->wsched);
628 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p can read\n", m);
629 if (!test_and_set_bit(Rworksched, &m->wsched)) {
630 P9_DPRINTK(P9_DEBUG_TRANS, "sched read work %p\n", m);
631 queue_work(p9_mux_wq, &m->rq);
632 }
633 }
634
635 if (n & POLLOUT) {
636 set_bit(Wpending, &m->wsched);
637 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p can write\n", m);
638 if ((m->wsize || !list_empty(&m->unsent_req_list)) &&
639 !test_and_set_bit(Wworksched, &m->wsched)) {
640 P9_DPRINTK(P9_DEBUG_TRANS, "sched write work %p\n", m);
641 queue_work(p9_mux_wq, &m->wq);
642 }
643 }
644 }
645
646 /**
647 * p9_fd_request - send 9P request
648 * The function can sleep until the request is scheduled for sending.
649 * The function can be interrupted. Return from the function is not
650 * a guarantee that the request is sent successfully.
651 *
652 * @client: client instance
653 * @req: request to be sent
654 *
655 */
656
657 static int p9_fd_request(struct p9_client *client, struct p9_req_t *req)
658 {
659 int n;
660 struct p9_trans_fd *ts = client->trans;
661 struct p9_conn *m = ts->conn;
662
663 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p task %p tcall %p id %d\n", m,
664 current, req->tc, req->tc->id);
665 if (m->err < 0)
666 return m->err;
667
668 spin_lock(&client->lock);
669 req->status = REQ_STATUS_UNSENT;
670 list_add_tail(&req->req_list, &m->unsent_req_list);
671 spin_unlock(&client->lock);
672
673 if (test_and_clear_bit(Wpending, &m->wsched))
674 n = POLLOUT;
675 else
676 n = p9_fd_poll(m->client, NULL);
677
678 if (n & POLLOUT && !test_and_set_bit(Wworksched, &m->wsched))
679 queue_work(p9_mux_wq, &m->wq);
680
681 return 0;
682 }
683
684 static int p9_fd_cancel(struct p9_client *client, struct p9_req_t *req)
685 {
686 int ret = 1;
687
688 P9_DPRINTK(P9_DEBUG_TRANS, "client %p req %p\n", client, req);
689
690 spin_lock(&client->lock);
691
692 if (req->status == REQ_STATUS_UNSENT) {
693 list_del(&req->req_list);
694 req->status = REQ_STATUS_FLSHD;
695 ret = 0;
696 } else if (req->status == REQ_STATUS_SENT)
697 req->status = REQ_STATUS_FLSH;
698
699 spin_unlock(&client->lock);
700
701 return ret;
702 }
703
704 /**
705 * parse_opts - parse mount options into p9_fd_opts structure
706 * @params: options string passed from mount
707 * @opts: fd transport-specific structure to parse options into
708 *
709 * Returns 0 upon success, -ERRNO upon failure
710 */
711
712 static int parse_opts(char *params, struct p9_fd_opts *opts)
713 {
714 char *p;
715 substring_t args[MAX_OPT_ARGS];
716 int option;
717 char *options, *tmp_options;
718 int ret;
719
720 opts->port = P9_PORT;
721 opts->rfd = ~0;
722 opts->wfd = ~0;
723
724 if (!params)
725 return 0;
726
727 tmp_options = kstrdup(params, GFP_KERNEL);
728 if (!tmp_options) {
729 P9_DPRINTK(P9_DEBUG_ERROR,
730 "failed to allocate copy of option string\n");
731 return -ENOMEM;
732 }
733 options = tmp_options;
734
735 while ((p = strsep(&options, ",")) != NULL) {
736 int token;
737 int r;
738 if (!*p)
739 continue;
740 token = match_token(p, tokens, args);
741 if (token != Opt_err) {
742 r = match_int(&args[0], &option);
743 if (r < 0) {
744 P9_DPRINTK(P9_DEBUG_ERROR,
745 "integer field, but no integer?\n");
746 ret = r;
747 continue;
748 }
749 }
750 switch (token) {
751 case Opt_port:
752 opts->port = option;
753 break;
754 case Opt_rfdno:
755 opts->rfd = option;
756 break;
757 case Opt_wfdno:
758 opts->wfd = option;
759 break;
760 default:
761 continue;
762 }
763 }
764
765 kfree(tmp_options);
766 return 0;
767 }
768
769 static int p9_fd_open(struct p9_client *client, int rfd, int wfd)
770 {
771 struct p9_trans_fd *ts = kmalloc(sizeof(struct p9_trans_fd),
772 GFP_KERNEL);
773 if (!ts)
774 return -ENOMEM;
775
776 ts->rd = fget(rfd);
777 ts->wr = fget(wfd);
778 if (!ts->rd || !ts->wr) {
779 if (ts->rd)
780 fput(ts->rd);
781 if (ts->wr)
782 fput(ts->wr);
783 kfree(ts);
784 return -EIO;
785 }
786
787 client->trans = ts;
788 client->status = Connected;
789
790 return 0;
791 }
792
793 static int p9_socket_open(struct p9_client *client, struct socket *csocket)
794 {
795 struct p9_trans_fd *p;
796 int ret, fd;
797
798 p = kmalloc(sizeof(struct p9_trans_fd), GFP_KERNEL);
799 if (!p)
800 return -ENOMEM;
801
802 csocket->sk->sk_allocation = GFP_NOIO;
803 fd = sock_map_fd(csocket, 0);
804 if (fd < 0) {
805 P9_EPRINTK(KERN_ERR, "p9_socket_open: failed to map fd\n");
806 sock_release(csocket);
807 kfree(p);
808 return fd;
809 }
810
811 get_file(csocket->file);
812 get_file(csocket->file);
813 p->wr = p->rd = csocket->file;
814 client->trans = p;
815 client->status = Connected;
816
817 sys_close(fd); /* still racy */
818
819 p->rd->f_flags |= O_NONBLOCK;
820
821 p->conn = p9_conn_create(client);
822 if (IS_ERR(p->conn)) {
823 ret = PTR_ERR(p->conn);
824 p->conn = NULL;
825 kfree(p);
826 sockfd_put(csocket);
827 sockfd_put(csocket);
828 return ret;
829 }
830 return 0;
831 }
832
833 /**
834 * p9_mux_destroy - cancels all pending requests and frees mux resources
835 * @m: mux to destroy
836 *
837 */
838
839 static void p9_conn_destroy(struct p9_conn *m)
840 {
841 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p prev %p next %p\n", m,
842 m->mux_list.prev, m->mux_list.next);
843
844 p9_mux_poll_stop(m);
845 cancel_work_sync(&m->rq);
846 cancel_work_sync(&m->wq);
847
848 p9_conn_cancel(m, -ECONNRESET);
849
850 m->client = NULL;
851 kfree(m);
852 }
853
854 /**
855 * p9_fd_close - shutdown file descriptor transport
856 * @client: client instance
857 *
858 */
859
860 static void p9_fd_close(struct p9_client *client)
861 {
862 struct p9_trans_fd *ts;
863
864 if (!client)
865 return;
866
867 ts = client->trans;
868 if (!ts)
869 return;
870
871 client->status = Disconnected;
872
873 p9_conn_destroy(ts->conn);
874
875 if (ts->rd)
876 fput(ts->rd);
877 if (ts->wr)
878 fput(ts->wr);
879
880 kfree(ts);
881 }
882
883 /*
884 * stolen from NFS - maybe should be made a generic function?
885 */
886 static inline int valid_ipaddr4(const char *buf)
887 {
888 int rc, count, in[4];
889
890 rc = sscanf(buf, "%d.%d.%d.%d", &in[0], &in[1], &in[2], &in[3]);
891 if (rc != 4)
892 return -EINVAL;
893 for (count = 0; count < 4; count++) {
894 if (in[count] > 255)
895 return -EINVAL;
896 }
897 return 0;
898 }
899
900 static int
901 p9_fd_create_tcp(struct p9_client *client, const char *addr, char *args)
902 {
903 int err;
904 struct socket *csocket;
905 struct sockaddr_in sin_server;
906 struct p9_fd_opts opts;
907
908 err = parse_opts(args, &opts);
909 if (err < 0)
910 return err;
911
912 if (valid_ipaddr4(addr) < 0)
913 return -EINVAL;
914
915 csocket = NULL;
916
917 sin_server.sin_family = AF_INET;
918 sin_server.sin_addr.s_addr = in_aton(addr);
919 sin_server.sin_port = htons(opts.port);
920 err = sock_create_kern(PF_INET, SOCK_STREAM, IPPROTO_TCP, &csocket);
921
922 if (err) {
923 P9_EPRINTK(KERN_ERR, "p9_trans_tcp: problem creating socket\n");
924 return err;
925 }
926
927 err = csocket->ops->connect(csocket,
928 (struct sockaddr *)&sin_server,
929 sizeof(struct sockaddr_in), 0);
930 if (err < 0) {
931 P9_EPRINTK(KERN_ERR,
932 "p9_trans_tcp: problem connecting socket to %s\n",
933 addr);
934 sock_release(csocket);
935 return err;
936 }
937
938 return p9_socket_open(client, csocket);
939 }
940
941 static int
942 p9_fd_create_unix(struct p9_client *client, const char *addr, char *args)
943 {
944 int err;
945 struct socket *csocket;
946 struct sockaddr_un sun_server;
947
948 csocket = NULL;
949
950 if (strlen(addr) > UNIX_PATH_MAX) {
951 P9_EPRINTK(KERN_ERR, "p9_trans_unix: address too long: %s\n",
952 addr);
953 return -ENAMETOOLONG;
954 }
955
956 sun_server.sun_family = PF_UNIX;
957 strcpy(sun_server.sun_path, addr);
958 err = sock_create_kern(PF_UNIX, SOCK_STREAM, 0, &csocket);
959 if (err < 0) {
960 P9_EPRINTK(KERN_ERR, "p9_trans_unix: problem creating socket\n");
961 return err;
962 }
963 err = csocket->ops->connect(csocket, (struct sockaddr *)&sun_server,
964 sizeof(struct sockaddr_un) - 1, 0);
965 if (err < 0) {
966 P9_EPRINTK(KERN_ERR,
967 "p9_trans_unix: problem connecting socket: %s: %d\n",
968 addr, err);
969 sock_release(csocket);
970 return err;
971 }
972
973 return p9_socket_open(client, csocket);
974 }
975
976 static int
977 p9_fd_create(struct p9_client *client, const char *addr, char *args)
978 {
979 int err;
980 struct p9_fd_opts opts;
981 struct p9_trans_fd *p;
982
983 parse_opts(args, &opts);
984
985 if (opts.rfd == ~0 || opts.wfd == ~0) {
986 printk(KERN_ERR "v9fs: Insufficient options for proto=fd\n");
987 return -ENOPROTOOPT;
988 }
989
990 err = p9_fd_open(client, opts.rfd, opts.wfd);
991 if (err < 0)
992 return err;
993
994 p = (struct p9_trans_fd *) client->trans;
995 p->conn = p9_conn_create(client);
996 if (IS_ERR(p->conn)) {
997 err = PTR_ERR(p->conn);
998 p->conn = NULL;
999 fput(p->rd);
1000 fput(p->wr);
1001 return err;
1002 }
1003
1004 return 0;
1005 }
1006
1007 static struct p9_trans_module p9_tcp_trans = {
1008 .name = "tcp",
1009 .maxsize = MAX_SOCK_BUF,
1010 .def = 1,
1011 .create = p9_fd_create_tcp,
1012 .close = p9_fd_close,
1013 .request = p9_fd_request,
1014 .cancel = p9_fd_cancel,
1015 .owner = THIS_MODULE,
1016 };
1017
1018 static struct p9_trans_module p9_unix_trans = {
1019 .name = "unix",
1020 .maxsize = MAX_SOCK_BUF,
1021 .def = 0,
1022 .create = p9_fd_create_unix,
1023 .close = p9_fd_close,
1024 .request = p9_fd_request,
1025 .cancel = p9_fd_cancel,
1026 .owner = THIS_MODULE,
1027 };
1028
1029 static struct p9_trans_module p9_fd_trans = {
1030 .name = "fd",
1031 .maxsize = MAX_SOCK_BUF,
1032 .def = 0,
1033 .create = p9_fd_create,
1034 .close = p9_fd_close,
1035 .request = p9_fd_request,
1036 .cancel = p9_fd_cancel,
1037 .owner = THIS_MODULE,
1038 };
1039
1040 /**
1041 * p9_poll_proc - poll worker thread
1042 * @a: thread state and arguments
1043 *
1044 * polls all v9fs transports for new events and queues the appropriate
1045 * work to the work queue
1046 *
1047 */
1048
1049 static int p9_poll_proc(void *a)
1050 {
1051 unsigned long flags;
1052
1053 P9_DPRINTK(P9_DEBUG_TRANS, "start %p\n", current);
1054 repeat:
1055 spin_lock_irqsave(&p9_poll_lock, flags);
1056 while (!list_empty(&p9_poll_pending_list)) {
1057 struct p9_conn *conn = list_first_entry(&p9_poll_pending_list,
1058 struct p9_conn,
1059 poll_pending_link);
1060 list_del_init(&conn->poll_pending_link);
1061 spin_unlock_irqrestore(&p9_poll_lock, flags);
1062
1063 p9_poll_mux(conn);
1064
1065 spin_lock_irqsave(&p9_poll_lock, flags);
1066 }
1067 spin_unlock_irqrestore(&p9_poll_lock, flags);
1068
1069 set_current_state(TASK_INTERRUPTIBLE);
1070 if (list_empty(&p9_poll_pending_list)) {
1071 P9_DPRINTK(P9_DEBUG_TRANS, "sleeping...\n");
1072 schedule();
1073 }
1074 __set_current_state(TASK_RUNNING);
1075
1076 if (!kthread_should_stop())
1077 goto repeat;
1078
1079 P9_DPRINTK(P9_DEBUG_TRANS, "finish\n");
1080 return 0;
1081 }
1082
1083 int p9_trans_fd_init(void)
1084 {
1085 p9_mux_wq = create_workqueue("v9fs");
1086 if (!p9_mux_wq) {
1087 printk(KERN_WARNING "v9fs: mux: creating workqueue failed\n");
1088 return -ENOMEM;
1089 }
1090
1091 p9_poll_task = kthread_run(p9_poll_proc, NULL, "v9fs-poll");
1092 if (IS_ERR(p9_poll_task)) {
1093 destroy_workqueue(p9_mux_wq);
1094 printk(KERN_WARNING "v9fs: mux: creating poll task failed\n");
1095 return PTR_ERR(p9_poll_task);
1096 }
1097
1098 v9fs_register_trans(&p9_tcp_trans);
1099 v9fs_register_trans(&p9_unix_trans);
1100 v9fs_register_trans(&p9_fd_trans);
1101
1102 return 0;
1103 }
1104
1105 void p9_trans_fd_exit(void)
1106 {
1107 kthread_stop(p9_poll_task);
1108 v9fs_unregister_trans(&p9_tcp_trans);
1109 v9fs_unregister_trans(&p9_unix_trans);
1110 v9fs_unregister_trans(&p9_fd_trans);
1111
1112 destroy_workqueue(p9_mux_wq);
1113 }
linux 2.6 git repository for openrd