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Linux 2.6.31.6
[linux/fpc-iii.git] / net / 9p / trans_fd.c
blob8d934dd7fd5424049a811906e0467da91da208c3
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 #define P9_PORT 564
46 #define MAX_SOCK_BUF (64*1024)
47 #define MAXPOLLWADDR 2
48
49 /**
50 * struct p9_fd_opts - per-transport options
51 * @rfd: file descriptor for reading (trans=fd)
52 * @wfd: file descriptor for writing (trans=fd)
53 * @port: port to connect to (trans=tcp)
54 *
55 */
56
57 struct p9_fd_opts {
58 int rfd;
59 int wfd;
60 u16 port;
61 };
62
63 /**
64 * struct p9_trans_fd - transport state
65 * @rd: reference to file to read from
66 * @wr: reference of file to write to
67 * @conn: connection state reference
68 *
69 */
70
71 struct p9_trans_fd {
72 struct file *rd;
73 struct file *wr;
74 struct p9_conn *conn;
75 };
76
77 /*
78 * Option Parsing (code inspired by NFS code)
79 * - a little lazy - parse all fd-transport options
80 */
81
82 enum {
83 /* Options that take integer arguments */
84 Opt_port, Opt_rfdno, Opt_wfdno, Opt_err,
85 };
86
87 static const match_table_t tokens = {
88 {Opt_port, "port=%u"},
89 {Opt_rfdno, "rfdno=%u"},
90 {Opt_wfdno, "wfdno=%u"},
91 {Opt_err, NULL},
92 };
93
94 enum {
95 Rworksched = 1, /* read work scheduled or running */
96 Rpending = 2, /* can read */
97 Wworksched = 4, /* write work scheduled or running */
98 Wpending = 8, /* can write */
99 };
100
101 struct p9_poll_wait {
102 struct p9_conn *conn;
103 wait_queue_t wait;
104 wait_queue_head_t *wait_addr;
105 };
106
107 /**
108 * struct p9_conn - fd mux connection state information
109 * @mux_list: list link for mux to manage multiple connections (?)
110 * @client: reference to client instance for this connection
111 * @err: error state
112 * @req_list: accounting for requests which have been sent
113 * @unsent_req_list: accounting for requests that haven't been sent
114 * @req: current request being processed (if any)
115 * @tmp_buf: temporary buffer to read in header
116 * @rsize: amount to read for current frame
117 * @rpos: read position in current frame
118 * @rbuf: current read buffer
119 * @wpos: write position for current frame
120 * @wsize: amount of data to write for current frame
121 * @wbuf: current write buffer
122 * @poll_pending_link: pending links to be polled per conn
123 * @poll_wait: array of wait_q's for various worker threads
124 * @pt: poll state
125 * @rq: current read work
126 * @wq: current write work
127 * @wsched: ????
128 *
129 */
130
131 struct p9_conn {
132 struct list_head mux_list;
133 struct p9_client *client;
134 int err;
135 struct list_head req_list;
136 struct list_head unsent_req_list;
137 struct p9_req_t *req;
138 char tmp_buf[7];
139 int rsize;
140 int rpos;
141 char *rbuf;
142 int wpos;
143 int wsize;
144 char *wbuf;
145 struct list_head poll_pending_link;
146 struct p9_poll_wait poll_wait[MAXPOLLWADDR];
147 poll_table pt;
148 struct work_struct rq;
149 struct work_struct wq;
150 unsigned long wsched;
151 };
152
153 static DEFINE_SPINLOCK(p9_poll_lock);
154 static LIST_HEAD(p9_poll_pending_list);
155 static struct workqueue_struct *p9_mux_wq;
156 static struct task_struct *p9_poll_task;
157
158 static void p9_mux_poll_stop(struct p9_conn *m)
159 {
160 unsigned long flags;
161 int i;
162
163 for (i = 0; i < ARRAY_SIZE(m->poll_wait); i++) {
164 struct p9_poll_wait *pwait = &m->poll_wait[i];
165
166 if (pwait->wait_addr) {
167 remove_wait_queue(pwait->wait_addr, &pwait->wait);
168 pwait->wait_addr = NULL;
169 }
170 }
171
172 spin_lock_irqsave(&p9_poll_lock, flags);
173 list_del_init(&m->poll_pending_link);
174 spin_unlock_irqrestore(&p9_poll_lock, flags);
175 }
176
177 /**
178 * p9_conn_cancel - cancel all pending requests with error
179 * @m: mux data
180 * @err: error code
181 *
182 */
183
184 static void p9_conn_cancel(struct p9_conn *m, int err)
185 {
186 struct p9_req_t *req, *rtmp;
187 unsigned long flags;
188 LIST_HEAD(cancel_list);
189
190 P9_DPRINTK(P9_DEBUG_ERROR, "mux %p err %d\n", m, err);
191
192 spin_lock_irqsave(&m->client->lock, flags);
193
194 if (m->err) {
195 spin_unlock_irqrestore(&m->client->lock, flags);
196 return;
197 }
198
199 m->err = err;
200
201 list_for_each_entry_safe(req, rtmp, &m->req_list, req_list) {
202 req->status = REQ_STATUS_ERROR;
203 if (!req->t_err)
204 req->t_err = err;
205 list_move(&req->req_list, &cancel_list);
206 }
207 list_for_each_entry_safe(req, rtmp, &m->unsent_req_list, req_list) {
208 req->status = REQ_STATUS_ERROR;
209 if (!req->t_err)
210 req->t_err = err;
211 list_move(&req->req_list, &cancel_list);
212 }
213 spin_unlock_irqrestore(&m->client->lock, flags);
214
215 list_for_each_entry_safe(req, rtmp, &cancel_list, req_list) {
216 P9_DPRINTK(P9_DEBUG_ERROR, "call back req %p\n", req);
217 list_del(&req->req_list);
218 p9_client_cb(m->client, req);
219 }
220 }
221
222 static unsigned int
223 p9_fd_poll(struct p9_client *client, struct poll_table_struct *pt)
224 {
225 int ret, n;
226 struct p9_trans_fd *ts = NULL;
227
228 if (client && client->status == Connected)
229 ts = client->trans;
230
231 if (!ts)
232 return -EREMOTEIO;
233
234 if (!ts->rd->f_op || !ts->rd->f_op->poll)
235 return -EIO;
236
237 if (!ts->wr->f_op || !ts->wr->f_op->poll)
238 return -EIO;
239
240 ret = ts->rd->f_op->poll(ts->rd, pt);
241 if (ret < 0)
242 return ret;
243
244 if (ts->rd != ts->wr) {
245 n = ts->wr->f_op->poll(ts->wr, pt);
246 if (n < 0)
247 return n;
248 ret = (ret & ~POLLOUT) | (n & ~POLLIN);
249 }
250
251 return ret;
252 }
253
254 /**
255 * p9_fd_read- read from a fd
256 * @client: client instance
257 * @v: buffer to receive data into
258 * @len: size of receive buffer
259 *
260 */
261
262 static int p9_fd_read(struct p9_client *client, void *v, int len)
263 {
264 int ret;
265 struct p9_trans_fd *ts = NULL;
266
267 if (client && client->status != Disconnected)
268 ts = client->trans;
269
270 if (!ts)
271 return -EREMOTEIO;
272
273 if (!(ts->rd->f_flags & O_NONBLOCK))
274 P9_DPRINTK(P9_DEBUG_ERROR, "blocking read ...\n");
275
276 ret = kernel_read(ts->rd, ts->rd->f_pos, v, len);
277 if (ret <= 0 && ret != -ERESTARTSYS && ret != -EAGAIN)
278 client->status = Disconnected;
279 return ret;
280 }
281
282 /**
283 * p9_read_work - called when there is some data to be read from a transport
284 * @work: container of work to be done
285 *
286 */
287
288 static void p9_read_work(struct work_struct *work)
289 {
290 int n, err;
291 struct p9_conn *m;
292
293 m = container_of(work, struct p9_conn, rq);
294
295 if (m->err < 0)
296 return;
297
298 P9_DPRINTK(P9_DEBUG_TRANS, "start mux %p pos %d\n", m, m->rpos);
299
300 if (!m->rbuf) {
301 m->rbuf = m->tmp_buf;
302 m->rpos = 0;
303 m->rsize = 7; /* start by reading header */
304 }
305
306 clear_bit(Rpending, &m->wsched);
307 P9_DPRINTK(P9_DEBUG_TRANS, "read mux %p pos %d size: %d = %d\n", m,
308 m->rpos, m->rsize, m->rsize-m->rpos);
309 err = p9_fd_read(m->client, m->rbuf + m->rpos,
310 m->rsize - m->rpos);
311 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p got %d bytes\n", m, err);
312 if (err == -EAGAIN) {
313 clear_bit(Rworksched, &m->wsched);
314 return;
315 }
316
317 if (err <= 0)
318 goto error;
319
320 m->rpos += err;
321
322 if ((!m->req) && (m->rpos == m->rsize)) { /* header read in */
323 u16 tag;
324 P9_DPRINTK(P9_DEBUG_TRANS, "got new header\n");
325
326 n = le32_to_cpu(*(__le32 *) m->rbuf); /* read packet size */
327 if (n >= m->client->msize) {
328 P9_DPRINTK(P9_DEBUG_ERROR,
329 "requested packet size too big: %d\n", n);
330 err = -EIO;
331 goto error;
332 }
333
334 tag = le16_to_cpu(*(__le16 *) (m->rbuf+5)); /* read tag */
335 P9_DPRINTK(P9_DEBUG_TRANS,
336 "mux %p pkt: size: %d bytes tag: %d\n", m, n, tag);
337
338 m->req = p9_tag_lookup(m->client, tag);
339 if (!m->req || (m->req->status != REQ_STATUS_SENT &&
340 m->req->status != REQ_STATUS_FLSH)) {
341 P9_DPRINTK(P9_DEBUG_ERROR, "Unexpected packet tag %d\n",
342 tag);
343 err = -EIO;
344 goto error;
345 }
346
347 if (m->req->rc == NULL) {
348 m->req->rc = kmalloc(sizeof(struct p9_fcall) +
349 m->client->msize, GFP_KERNEL);
350 if (!m->req->rc) {
351 m->req = NULL;
352 err = -ENOMEM;
353 goto error;
354 }
355 }
356 m->rbuf = (char *)m->req->rc + sizeof(struct p9_fcall);
357 memcpy(m->rbuf, m->tmp_buf, m->rsize);
358 m->rsize = n;
359 }
360
361 /* not an else because some packets (like clunk) have no payload */
362 if ((m->req) && (m->rpos == m->rsize)) { /* packet is read in */
363 P9_DPRINTK(P9_DEBUG_TRANS, "got new packet\n");
364 spin_lock(&m->client->lock);
365 if (m->req->status != REQ_STATUS_ERROR)
366 m->req->status = REQ_STATUS_RCVD;
367 list_del(&m->req->req_list);
368 spin_unlock(&m->client->lock);
369 p9_client_cb(m->client, m->req);
370 m->rbuf = NULL;
371 m->rpos = 0;
372 m->rsize = 0;
373 m->req = NULL;
374 }
375
376 if (!list_empty(&m->req_list)) {
377 if (test_and_clear_bit(Rpending, &m->wsched))
378 n = POLLIN;
379 else
380 n = p9_fd_poll(m->client, NULL);
381
382 if (n & POLLIN) {
383 P9_DPRINTK(P9_DEBUG_TRANS, "sched read work %p\n", m);
384 queue_work(p9_mux_wq, &m->rq);
385 } else
386 clear_bit(Rworksched, &m->wsched);
387 } else
388 clear_bit(Rworksched, &m->wsched);
389
390 return;
391 error:
392 p9_conn_cancel(m, err);
393 clear_bit(Rworksched, &m->wsched);
394 }
395
396 /**
397 * p9_fd_write - write to a socket
398 * @client: client instance
399 * @v: buffer to send data from
400 * @len: size of send buffer
401 *
402 */
403
404 static int p9_fd_write(struct p9_client *client, void *v, int len)
405 {
406 int ret;
407 mm_segment_t oldfs;
408 struct p9_trans_fd *ts = NULL;
409
410 if (client && client->status != Disconnected)
411 ts = client->trans;
412
413 if (!ts)
414 return -EREMOTEIO;
415
416 if (!(ts->wr->f_flags & O_NONBLOCK))
417 P9_DPRINTK(P9_DEBUG_ERROR, "blocking write ...\n");
418
419 oldfs = get_fs();
420 set_fs(get_ds());
421 /* The cast to a user pointer is valid due to the set_fs() */
422 ret = vfs_write(ts->wr, (__force void __user *)v, len, &ts->wr->f_pos);
423 set_fs(oldfs);
424
425 if (ret <= 0 && ret != -ERESTARTSYS && ret != -EAGAIN)
426 client->status = Disconnected;
427 return ret;
428 }
429
430 /**
431 * p9_write_work - called when a transport can send some data
432 * @work: container for work to be done
433 *
434 */
435
436 static void p9_write_work(struct work_struct *work)
437 {
438 int n, err;
439 struct p9_conn *m;
440 struct p9_req_t *req;
441
442 m = container_of(work, struct p9_conn, wq);
443
444 if (m->err < 0) {
445 clear_bit(Wworksched, &m->wsched);
446 return;
447 }
448
449 if (!m->wsize) {
450 if (list_empty(&m->unsent_req_list)) {
451 clear_bit(Wworksched, &m->wsched);
452 return;
453 }
454
455 spin_lock(&m->client->lock);
456 req = list_entry(m->unsent_req_list.next, struct p9_req_t,
457 req_list);
458 req->status = REQ_STATUS_SENT;
459 P9_DPRINTK(P9_DEBUG_TRANS, "move req %p\n", req);
460 list_move_tail(&req->req_list, &m->req_list);
461
462 m->wbuf = req->tc->sdata;
463 m->wsize = req->tc->size;
464 m->wpos = 0;
465 spin_unlock(&m->client->lock);
466 }
467
468 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p pos %d size %d\n", m, m->wpos,
469 m->wsize);
470 clear_bit(Wpending, &m->wsched);
471 err = p9_fd_write(m->client, m->wbuf + m->wpos, m->wsize - m->wpos);
472 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p sent %d bytes\n", m, err);
473 if (err == -EAGAIN) {
474 clear_bit(Wworksched, &m->wsched);
475 return;
476 }
477
478 if (err < 0)
479 goto error;
480 else if (err == 0) {
481 err = -EREMOTEIO;
482 goto error;
483 }
484
485 m->wpos += err;
486 if (m->wpos == m->wsize)
487 m->wpos = m->wsize = 0;
488
489 if (m->wsize == 0 && !list_empty(&m->unsent_req_list)) {
490 if (test_and_clear_bit(Wpending, &m->wsched))
491 n = POLLOUT;
492 else
493 n = p9_fd_poll(m->client, NULL);
494
495 if (n & POLLOUT) {
496 P9_DPRINTK(P9_DEBUG_TRANS, "sched write work %p\n", m);
497 queue_work(p9_mux_wq, &m->wq);
498 } else
499 clear_bit(Wworksched, &m->wsched);
500 } else
501 clear_bit(Wworksched, &m->wsched);
502
503 return;
504
505 error:
506 p9_conn_cancel(m, err);
507 clear_bit(Wworksched, &m->wsched);
508 }
509
510 static int p9_pollwake(wait_queue_t *wait, unsigned mode, int sync, void *key)
511 {
512 struct p9_poll_wait *pwait =
513 container_of(wait, struct p9_poll_wait, wait);
514 struct p9_conn *m = pwait->conn;
515 unsigned long flags;
516 DECLARE_WAITQUEUE(dummy_wait, p9_poll_task);
517
518 spin_lock_irqsave(&p9_poll_lock, flags);
519 if (list_empty(&m->poll_pending_link))
520 list_add_tail(&m->poll_pending_link, &p9_poll_pending_list);
521 spin_unlock_irqrestore(&p9_poll_lock, flags);
522
523 /* perform the default wake up operation */
524 return default_wake_function(&dummy_wait, mode, sync, key);
525 }
526
527 /**
528 * p9_pollwait - add poll task to the wait queue
529 * @filp: file pointer being polled
530 * @wait_address: wait_q to block on
531 * @p: poll state
532 *
533 * called by files poll operation to add v9fs-poll task to files wait queue
534 */
535
536 static void
537 p9_pollwait(struct file *filp, wait_queue_head_t *wait_address, poll_table *p)
538 {
539 struct p9_conn *m = container_of(p, struct p9_conn, pt);
540 struct p9_poll_wait *pwait = NULL;
541 int i;
542
543 for (i = 0; i < ARRAY_SIZE(m->poll_wait); i++) {
544 if (m->poll_wait[i].wait_addr == NULL) {
545 pwait = &m->poll_wait[i];
546 break;
547 }
548 }
549
550 if (!pwait) {
551 P9_DPRINTK(P9_DEBUG_ERROR, "not enough wait_address slots\n");
552 return;
553 }
554
555 pwait->conn = m;
556 pwait->wait_addr = wait_address;
557 init_waitqueue_func_entry(&pwait->wait, p9_pollwake);
558 add_wait_queue(wait_address, &pwait->wait);
559 }
560
561 /**
562 * p9_conn_create - allocate and initialize the per-session mux data
563 * @client: client instance
564 *
565 * Note: Creates the polling task if this is the first session.
566 */
567
568 static struct p9_conn *p9_conn_create(struct p9_client *client)
569 {
570 int n;
571 struct p9_conn *m;
572
573 P9_DPRINTK(P9_DEBUG_TRANS, "client %p msize %d\n", client,
574 client->msize);
575 m = kzalloc(sizeof(struct p9_conn), GFP_KERNEL);
576 if (!m)
577 return ERR_PTR(-ENOMEM);
578
579 INIT_LIST_HEAD(&m->mux_list);
580 m->client = client;
581
582 INIT_LIST_HEAD(&m->req_list);
583 INIT_LIST_HEAD(&m->unsent_req_list);
584 INIT_WORK(&m->rq, p9_read_work);
585 INIT_WORK(&m->wq, p9_write_work);
586 INIT_LIST_HEAD(&m->poll_pending_link);
587 init_poll_funcptr(&m->pt, p9_pollwait);
588
589 n = p9_fd_poll(client, &m->pt);
590 if (n & POLLIN) {
591 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p can read\n", m);
592 set_bit(Rpending, &m->wsched);
593 }
594
595 if (n & POLLOUT) {
596 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p can write\n", m);
597 set_bit(Wpending, &m->wsched);
598 }
599
600 return m;
601 }
602
603 /**
604 * p9_poll_mux - polls a mux and schedules read or write works if necessary
605 * @m: connection to poll
606 *
607 */
608
609 static void p9_poll_mux(struct p9_conn *m)
610 {
611 int n;
612
613 if (m->err < 0)
614 return;
615
616 n = p9_fd_poll(m->client, NULL);
617 if (n < 0 || n & (POLLERR | POLLHUP | POLLNVAL)) {
618 P9_DPRINTK(P9_DEBUG_TRANS, "error mux %p err %d\n", m, n);
619 if (n >= 0)
620 n = -ECONNRESET;
621 p9_conn_cancel(m, n);
622 }
623
624 if (n & POLLIN) {
625 set_bit(Rpending, &m->wsched);
626 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p can read\n", m);
627 if (!test_and_set_bit(Rworksched, &m->wsched)) {
628 P9_DPRINTK(P9_DEBUG_TRANS, "sched read work %p\n", m);
629 queue_work(p9_mux_wq, &m->rq);
630 }
631 }
632
633 if (n & POLLOUT) {
634 set_bit(Wpending, &m->wsched);
635 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p can write\n", m);
636 if ((m->wsize || !list_empty(&m->unsent_req_list))
637 && !test_and_set_bit(Wworksched, &m->wsched)) {
638 P9_DPRINTK(P9_DEBUG_TRANS, "sched write work %p\n", m);
639 queue_work(p9_mux_wq, &m->wq);
640 }
641 }
642 }
643
644 /**
645 * p9_fd_request - send 9P request
646 * The function can sleep until the request is scheduled for sending.
647 * The function can be interrupted. Return from the function is not
648 * a guarantee that the request is sent successfully.
649 *
650 * @client: client instance
651 * @req: request to be sent
652 *
653 */
654
655 static int p9_fd_request(struct p9_client *client, struct p9_req_t *req)
656 {
657 int n;
658 struct p9_trans_fd *ts = client->trans;
659 struct p9_conn *m = ts->conn;
660
661 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p task %p tcall %p id %d\n", m,
662 current, req->tc, req->tc->id);
663 if (m->err < 0)
664 return m->err;
665
666 spin_lock(&client->lock);
667 req->status = REQ_STATUS_UNSENT;
668 list_add_tail(&req->req_list, &m->unsent_req_list);
669 spin_unlock(&client->lock);
670
671 if (test_and_clear_bit(Wpending, &m->wsched))
672 n = POLLOUT;
673 else
674 n = p9_fd_poll(m->client, NULL);
675
676 if (n & POLLOUT && !test_and_set_bit(Wworksched, &m->wsched))
677 queue_work(p9_mux_wq, &m->wq);
678
679 return 0;
680 }
681
682 static int p9_fd_cancel(struct p9_client *client, struct p9_req_t *req)
683 {
684 int ret = 1;
685
686 P9_DPRINTK(P9_DEBUG_TRANS, "client %p req %p\n", client, req);
687
688 spin_lock(&client->lock);
689
690 if (req->status == REQ_STATUS_UNSENT) {
691 list_del(&req->req_list);
692 req->status = REQ_STATUS_FLSHD;
693 ret = 0;
694 } else if (req->status == REQ_STATUS_SENT)
695 req->status = REQ_STATUS_FLSH;
696
697 spin_unlock(&client->lock);
698
699 return ret;
700 }
701
702 /**
703 * parse_opts - parse mount options into p9_fd_opts structure
704 * @params: options string passed from mount
705 * @opts: fd transport-specific structure to parse options into
706 *
707 * Returns 0 upon success, -ERRNO upon failure
708 */
709
710 static int parse_opts(char *params, struct p9_fd_opts *opts)
711 {
712 char *p;
713 substring_t args[MAX_OPT_ARGS];
714 int option;
715 char *options;
716 int ret;
717
718 opts->port = P9_PORT;
719 opts->rfd = ~0;
720 opts->wfd = ~0;
721
722 if (!params)
723 return 0;
724
725 options = kstrdup(params, GFP_KERNEL);
726 if (!options) {
727 P9_DPRINTK(P9_DEBUG_ERROR,
728 "failed to allocate copy of option string\n");
729 return -ENOMEM;
730 }
731
732 while ((p = strsep(&options, ",")) != NULL) {
733 int token;
734 int r;
735 if (!*p)
736 continue;
737 token = match_token(p, tokens, args);
738 if (token != Opt_err) {
739 r = match_int(&args[0], &option);
740 if (r < 0) {
741 P9_DPRINTK(P9_DEBUG_ERROR,
742 "integer field, but no integer?\n");
743 ret = r;
744 continue;
745 }
746 }
747 switch (token) {
748 case Opt_port:
749 opts->port = option;
750 break;
751 case Opt_rfdno:
752 opts->rfd = option;
753 break;
754 case Opt_wfdno:
755 opts->wfd = option;
756 break;
757 default:
758 continue;
759 }
760 }
761 kfree(options);
762 return 0;
763 }
764
765 static int p9_fd_open(struct p9_client *client, int rfd, int wfd)
766 {
767 struct p9_trans_fd *ts = kmalloc(sizeof(struct p9_trans_fd),
768 GFP_KERNEL);
769 if (!ts)
770 return -ENOMEM;
771
772 ts->rd = fget(rfd);
773 ts->wr = fget(wfd);
774 if (!ts->rd || !ts->wr) {
775 if (ts->rd)
776 fput(ts->rd);
777 if (ts->wr)
778 fput(ts->wr);
779 kfree(ts);
780 return -EIO;
781 }
782
783 client->trans = ts;
784 client->status = Connected;
785
786 return 0;
787 }
788
789 static int p9_socket_open(struct p9_client *client, struct socket *csocket)
790 {
791 int fd, ret;
792
793 csocket->sk->sk_allocation = GFP_NOIO;
794 fd = sock_map_fd(csocket, 0);
795 if (fd < 0) {
796 P9_EPRINTK(KERN_ERR, "p9_socket_open: failed to map fd\n");
797 return fd;
798 }
799
800 ret = p9_fd_open(client, fd, fd);
801 if (ret < 0) {
802 P9_EPRINTK(KERN_ERR, "p9_socket_open: failed to open fd\n");
803 sockfd_put(csocket);
804 return ret;
805 }
806
807 ((struct p9_trans_fd *)client->trans)->rd->f_flags |= O_NONBLOCK;
808
809 return 0;
810 }
811
812 /**
813 * p9_mux_destroy - cancels all pending requests and frees mux resources
814 * @m: mux to destroy
815 *
816 */
817
818 static void p9_conn_destroy(struct p9_conn *m)
819 {
820 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p prev %p next %p\n", m,
821 m->mux_list.prev, m->mux_list.next);
822
823 p9_mux_poll_stop(m);
824 cancel_work_sync(&m->rq);
825 cancel_work_sync(&m->wq);
826
827 p9_conn_cancel(m, -ECONNRESET);
828
829 m->client = NULL;
830 kfree(m);
831 }
832
833 /**
834 * p9_fd_close - shutdown file descriptor transport
835 * @client: client instance
836 *
837 */
838
839 static void p9_fd_close(struct p9_client *client)
840 {
841 struct p9_trans_fd *ts;
842
843 if (!client)
844 return;
845
846 ts = client->trans;
847 if (!ts)
848 return;
849
850 client->status = Disconnected;
851
852 p9_conn_destroy(ts->conn);
853
854 if (ts->rd)
855 fput(ts->rd);
856 if (ts->wr)
857 fput(ts->wr);
858
859 kfree(ts);
860 }
861
862 /*
863 * stolen from NFS - maybe should be made a generic function?
864 */
865 static inline int valid_ipaddr4(const char *buf)
866 {
867 int rc, count, in[4];
868
869 rc = sscanf(buf, "%d.%d.%d.%d", &in[0], &in[1], &in[2], &in[3]);
870 if (rc != 4)
871 return -EINVAL;
872 for (count = 0; count < 4; count++) {
873 if (in[count] > 255)
874 return -EINVAL;
875 }
876 return 0;
877 }
878
879 static int
880 p9_fd_create_tcp(struct p9_client *client, const char *addr, char *args)
881 {
882 int err;
883 struct socket *csocket;
884 struct sockaddr_in sin_server;
885 struct p9_fd_opts opts;
886 struct p9_trans_fd *p = NULL; /* this gets allocated in p9_fd_open */
887
888 err = parse_opts(args, &opts);
889 if (err < 0)
890 return err;
891
892 if (valid_ipaddr4(addr) < 0)
893 return -EINVAL;
894
895 csocket = NULL;
896
897 sin_server.sin_family = AF_INET;
898 sin_server.sin_addr.s_addr = in_aton(addr);
899 sin_server.sin_port = htons(opts.port);
900 sock_create_kern(PF_INET, SOCK_STREAM, IPPROTO_TCP, &csocket);
901
902 if (!csocket) {
903 P9_EPRINTK(KERN_ERR, "p9_trans_tcp: problem creating socket\n");
904 err = -EIO;
905 goto error;
906 }
907
908 err = csocket->ops->connect(csocket,
909 (struct sockaddr *)&sin_server,
910 sizeof(struct sockaddr_in), 0);
911 if (err < 0) {
912 P9_EPRINTK(KERN_ERR,
913 "p9_trans_tcp: problem connecting socket to %s\n",
914 addr);
915 goto error;
916 }
917
918 err = p9_socket_open(client, csocket);
919 if (err < 0)
920 goto error;
921
922 p = (struct p9_trans_fd *) client->trans;
923 p->conn = p9_conn_create(client);
924 if (IS_ERR(p->conn)) {
925 err = PTR_ERR(p->conn);
926 p->conn = NULL;
927 goto error;
928 }
929
930 return 0;
931
932 error:
933 if (csocket)
934 sock_release(csocket);
935
936 kfree(p);
937
938 return err;
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 struct p9_trans_fd *p = NULL; /* this gets allocated in p9_fd_open */
948
949 csocket = NULL;
950
951 if (strlen(addr) > UNIX_PATH_MAX) {
952 P9_EPRINTK(KERN_ERR, "p9_trans_unix: address too long: %s\n",
953 addr);
954 err = -ENAMETOOLONG;
955 goto error;
956 }
957
958 sun_server.sun_family = PF_UNIX;
959 strcpy(sun_server.sun_path, addr);
960 sock_create_kern(PF_UNIX, SOCK_STREAM, 0, &csocket);
961 err = csocket->ops->connect(csocket, (struct sockaddr *)&sun_server,
962 sizeof(struct sockaddr_un) - 1, 0);
963 if (err < 0) {
964 P9_EPRINTK(KERN_ERR,
965 "p9_trans_unix: problem connecting socket: %s: %d\n",
966 addr, err);
967 goto error;
968 }
969
970 err = p9_socket_open(client, csocket);
971 if (err < 0)
972 goto error;
973
974 p = (struct p9_trans_fd *) client->trans;
975 p->conn = p9_conn_create(client);
976 if (IS_ERR(p->conn)) {
977 err = PTR_ERR(p->conn);
978 p->conn = NULL;
979 goto error;
980 }
981
982 return 0;
983
984 error:
985 if (csocket)
986 sock_release(csocket);
987
988 kfree(p);
989 return err;
990 }
991
992 static int
993 p9_fd_create(struct p9_client *client, const char *addr, char *args)
994 {
995 int err;
996 struct p9_fd_opts opts;
997 struct p9_trans_fd *p = NULL; /* this get allocated in p9_fd_open */
998
999 parse_opts(args, &opts);
1000
1001 if (opts.rfd == ~0 || opts.wfd == ~0) {
1002 printk(KERN_ERR "v9fs: Insufficient options for proto=fd\n");
1003 return -ENOPROTOOPT;
1004 }
1005
1006 err = p9_fd_open(client, opts.rfd, opts.wfd);
1007 if (err < 0)
1008 goto error;
1009
1010 p = (struct p9_trans_fd *) client->trans;
1011 p->conn = p9_conn_create(client);
1012 if (IS_ERR(p->conn)) {
1013 err = PTR_ERR(p->conn);
1014 p->conn = NULL;
1015 goto error;
1016 }
1017
1018 return 0;
1019
1020 error:
1021 kfree(p);
1022 return err;
1023 }
1024
1025 static struct p9_trans_module p9_tcp_trans = {
1026 .name = "tcp",
1027 .maxsize = MAX_SOCK_BUF,
1028 .def = 1,
1029 .create = p9_fd_create_tcp,
1030 .close = p9_fd_close,
1031 .request = p9_fd_request,
1032 .cancel = p9_fd_cancel,
1033 .owner = THIS_MODULE,
1034 };
1035
1036 static struct p9_trans_module p9_unix_trans = {
1037 .name = "unix",
1038 .maxsize = MAX_SOCK_BUF,
1039 .def = 0,
1040 .create = p9_fd_create_unix,
1041 .close = p9_fd_close,
1042 .request = p9_fd_request,
1043 .cancel = p9_fd_cancel,
1044 .owner = THIS_MODULE,
1045 };
1046
1047 static struct p9_trans_module p9_fd_trans = {
1048 .name = "fd",
1049 .maxsize = MAX_SOCK_BUF,
1050 .def = 0,
1051 .create = p9_fd_create,
1052 .close = p9_fd_close,
1053 .request = p9_fd_request,
1054 .cancel = p9_fd_cancel,
1055 .owner = THIS_MODULE,
1056 };
1057
1058 /**
1059 * p9_poll_proc - poll worker thread
1060 * @a: thread state and arguments
1061 *
1062 * polls all v9fs transports for new events and queues the appropriate
1063 * work to the work queue
1064 *
1065 */
1066
1067 static int p9_poll_proc(void *a)
1068 {
1069 unsigned long flags;
1070
1071 P9_DPRINTK(P9_DEBUG_TRANS, "start %p\n", current);
1072 repeat:
1073 spin_lock_irqsave(&p9_poll_lock, flags);
1074 while (!list_empty(&p9_poll_pending_list)) {
1075 struct p9_conn *conn = list_first_entry(&p9_poll_pending_list,
1076 struct p9_conn,
1077 poll_pending_link);
1078 list_del_init(&conn->poll_pending_link);
1079 spin_unlock_irqrestore(&p9_poll_lock, flags);
1080
1081 p9_poll_mux(conn);
1082
1083 spin_lock_irqsave(&p9_poll_lock, flags);
1084 }
1085 spin_unlock_irqrestore(&p9_poll_lock, flags);
1086
1087 set_current_state(TASK_INTERRUPTIBLE);
1088 if (list_empty(&p9_poll_pending_list)) {
1089 P9_DPRINTK(P9_DEBUG_TRANS, "sleeping...\n");
1090 schedule();
1091 }
1092 __set_current_state(TASK_RUNNING);
1093
1094 if (!kthread_should_stop())
1095 goto repeat;
1096
1097 P9_DPRINTK(P9_DEBUG_TRANS, "finish\n");
1098 return 0;
1099 }
1100
1101 int p9_trans_fd_init(void)
1102 {
1103 p9_mux_wq = create_workqueue("v9fs");
1104 if (!p9_mux_wq) {
1105 printk(KERN_WARNING "v9fs: mux: creating workqueue failed\n");
1106 return -ENOMEM;
1107 }
1108
1109 p9_poll_task = kthread_run(p9_poll_proc, NULL, "v9fs-poll");
1110 if (IS_ERR(p9_poll_task)) {
1111 destroy_workqueue(p9_mux_wq);
1112 printk(KERN_WARNING "v9fs: mux: creating poll task failed\n");
1113 return PTR_ERR(p9_poll_task);
1114 }
1115
1116 v9fs_register_trans(&p9_tcp_trans);
1117 v9fs_register_trans(&p9_unix_trans);
1118 v9fs_register_trans(&p9_fd_trans);
1119
1120 return 0;
1121 }
1122
1123 void p9_trans_fd_exit(void)
1124 {
1125 kthread_stop(p9_poll_task);
1126 v9fs_unregister_trans(&p9_tcp_trans);
1127 v9fs_unregister_trans(&p9_unix_trans);
1128 v9fs_unregister_trans(&p9_fd_trans);
1129
1130 destroy_workqueue(p9_mux_wq);
1131 }
Linux with added FPC-III support