Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
[pandora-kernel.git] / net / 9p / client.c
1 /*
2  * net/9p/clnt.c
3  *
4  * 9P Client
5  *
6  *  Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
7  *  Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License version 2
11  *  as published by the Free Software Foundation.
12  *
13  *  This program is distributed in the hope that it will be useful,
14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *  GNU General Public License for more details.
17  *
18  *  You should have received a copy of the GNU General Public License
19  *  along with this program; if not, write to:
20  *  Free Software Foundation
21  *  51 Franklin Street, Fifth Floor
22  *  Boston, MA  02111-1301  USA
23  *
24  */
25
26 #include <linux/module.h>
27 #include <linux/errno.h>
28 #include <linux/fs.h>
29 #include <linux/poll.h>
30 #include <linux/idr.h>
31 #include <linux/mutex.h>
32 #include <linux/slab.h>
33 #include <linux/sched.h>
34 #include <linux/uaccess.h>
35 #include <net/9p/9p.h>
36 #include <linux/parser.h>
37 #include <net/9p/client.h>
38 #include <net/9p/transport.h>
39 #include "protocol.h"
40
41 #define CREATE_TRACE_POINTS
42 #include <trace/events/9p.h>
43
44 /*
45   * Client Option Parsing (code inspired by NFS code)
46   *  - a little lazy - parse all client options
47   */
48
49 enum {
50         Opt_msize,
51         Opt_trans,
52         Opt_legacy,
53         Opt_version,
54         Opt_err,
55 };
56
57 static const match_table_t tokens = {
58         {Opt_msize, "msize=%u"},
59         {Opt_legacy, "noextend"},
60         {Opt_trans, "trans=%s"},
61         {Opt_version, "version=%s"},
62         {Opt_err, NULL},
63 };
64
65 inline int p9_is_proto_dotl(struct p9_client *clnt)
66 {
67         return clnt->proto_version == p9_proto_2000L;
68 }
69 EXPORT_SYMBOL(p9_is_proto_dotl);
70
71 inline int p9_is_proto_dotu(struct p9_client *clnt)
72 {
73         return clnt->proto_version == p9_proto_2000u;
74 }
75 EXPORT_SYMBOL(p9_is_proto_dotu);
76
77 /* Interpret mount option for protocol version */
78 static int get_protocol_version(char *s)
79 {
80         int version = -EINVAL;
81
82         if (!strcmp(s, "9p2000")) {
83                 version = p9_proto_legacy;
84                 P9_DPRINTK(P9_DEBUG_9P, "Protocol version: Legacy\n");
85         } else if (!strcmp(s, "9p2000.u")) {
86                 version = p9_proto_2000u;
87                 P9_DPRINTK(P9_DEBUG_9P, "Protocol version: 9P2000.u\n");
88         } else if (!strcmp(s, "9p2000.L")) {
89                 version = p9_proto_2000L;
90                 P9_DPRINTK(P9_DEBUG_9P, "Protocol version: 9P2000.L\n");
91         } else
92                 printk(KERN_INFO "9p: Unknown protocol version %s.\n", s);
93
94         return version;
95 }
96
97 /**
98  * parse_options - parse mount options into client structure
99  * @opts: options string passed from mount
100  * @clnt: existing v9fs client information
101  *
102  * Return 0 upon success, -ERRNO upon failure
103  */
104
105 static int parse_opts(char *opts, struct p9_client *clnt)
106 {
107         char *options, *tmp_options;
108         char *p;
109         substring_t args[MAX_OPT_ARGS];
110         int option;
111         char *s;
112         int ret = 0;
113
114         clnt->proto_version = p9_proto_2000u;
115         clnt->msize = 8192;
116
117         if (!opts)
118                 return 0;
119
120         tmp_options = kstrdup(opts, GFP_KERNEL);
121         if (!tmp_options) {
122                 P9_DPRINTK(P9_DEBUG_ERROR,
123                                 "failed to allocate copy of option string\n");
124                 return -ENOMEM;
125         }
126         options = tmp_options;
127
128         while ((p = strsep(&options, ",")) != NULL) {
129                 int token, r;
130                 if (!*p)
131                         continue;
132                 token = match_token(p, tokens, args);
133                 switch (token) {
134                 case Opt_msize:
135                         r = match_int(&args[0], &option);
136                         if (r < 0) {
137                                 P9_DPRINTK(P9_DEBUG_ERROR,
138                                            "integer field, but no integer?\n");
139                                 ret = r;
140                                 continue;
141                         }
142                         clnt->msize = option;
143                         break;
144                 case Opt_trans:
145                         s = match_strdup(&args[0]);
146                         if (!s) {
147                                 ret = -ENOMEM;
148                                 P9_DPRINTK(P9_DEBUG_ERROR,
149                                         "problem allocating copy of trans arg\n");
150                                 goto free_and_return;
151                          }
152                         clnt->trans_mod = v9fs_get_trans_by_name(s);
153                         if (clnt->trans_mod == NULL) {
154                                 printk(KERN_INFO
155                                         "9p: Could not find "
156                                         "request transport: %s\n", s);
157                                 ret = -EINVAL;
158                                 kfree(s);
159                                 goto free_and_return;
160                         }
161                         kfree(s);
162                         break;
163                 case Opt_legacy:
164                         clnt->proto_version = p9_proto_legacy;
165                         break;
166                 case Opt_version:
167                         s = match_strdup(&args[0]);
168                         if (!s) {
169                                 ret = -ENOMEM;
170                                 P9_DPRINTK(P9_DEBUG_ERROR,
171                                         "problem allocating copy of version arg\n");
172                                 goto free_and_return;
173                         }
174                         ret = get_protocol_version(s);
175                         if (ret == -EINVAL) {
176                                 kfree(s);
177                                 goto free_and_return;
178                         }
179                         kfree(s);
180                         clnt->proto_version = ret;
181                         break;
182                 default:
183                         continue;
184                 }
185         }
186
187 free_and_return:
188         kfree(tmp_options);
189         return ret;
190 }
191
192 /**
193  * p9_tag_alloc - lookup/allocate a request by tag
194  * @c: client session to lookup tag within
195  * @tag: numeric id for transaction
196  *
197  * this is a simple array lookup, but will grow the
198  * request_slots as necessary to accommodate transaction
199  * ids which did not previously have a slot.
200  *
201  * this code relies on the client spinlock to manage locks, its
202  * possible we should switch to something else, but I'd rather
203  * stick with something low-overhead for the common case.
204  *
205  */
206
207 static struct p9_req_t *
208 p9_tag_alloc(struct p9_client *c, u16 tag, unsigned int max_size)
209 {
210         unsigned long flags;
211         int row, col;
212         struct p9_req_t *req;
213         int alloc_msize = min(c->msize, max_size);
214
215         /* This looks up the original request by tag so we know which
216          * buffer to read the data into */
217         tag++;
218
219         if (tag >= c->max_tag) {
220                 spin_lock_irqsave(&c->lock, flags);
221                 /* check again since original check was outside of lock */
222                 while (tag >= c->max_tag) {
223                         row = (tag / P9_ROW_MAXTAG);
224                         c->reqs[row] = kcalloc(P9_ROW_MAXTAG,
225                                         sizeof(struct p9_req_t), GFP_ATOMIC);
226
227                         if (!c->reqs[row]) {
228                                 printk(KERN_ERR "Couldn't grow tag array\n");
229                                 spin_unlock_irqrestore(&c->lock, flags);
230                                 return ERR_PTR(-ENOMEM);
231                         }
232                         for (col = 0; col < P9_ROW_MAXTAG; col++) {
233                                 c->reqs[row][col].status = REQ_STATUS_IDLE;
234                                 c->reqs[row][col].tc = NULL;
235                         }
236                         c->max_tag += P9_ROW_MAXTAG;
237                 }
238                 spin_unlock_irqrestore(&c->lock, flags);
239         }
240         row = tag / P9_ROW_MAXTAG;
241         col = tag % P9_ROW_MAXTAG;
242
243         req = &c->reqs[row][col];
244         if (!req->tc) {
245                 req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_NOFS);
246                 if (!req->wq) {
247                         printk(KERN_ERR "Couldn't grow tag array\n");
248                         return ERR_PTR(-ENOMEM);
249                 }
250                 init_waitqueue_head(req->wq);
251                 req->tc = kmalloc(sizeof(struct p9_fcall) + alloc_msize,
252                                   GFP_NOFS);
253                 req->rc = kmalloc(sizeof(struct p9_fcall) + alloc_msize,
254                                   GFP_NOFS);
255                 if ((!req->tc) || (!req->rc)) {
256                         printk(KERN_ERR "Couldn't grow tag array\n");
257                         kfree(req->tc);
258                         kfree(req->rc);
259                         kfree(req->wq);
260                         req->tc = req->rc = NULL;
261                         req->wq = NULL;
262                         return ERR_PTR(-ENOMEM);
263                 }
264                 req->tc->capacity = alloc_msize;
265                 req->rc->capacity = alloc_msize;
266                 req->tc->sdata = (char *) req->tc + sizeof(struct p9_fcall);
267                 req->rc->sdata = (char *) req->rc + sizeof(struct p9_fcall);
268         }
269
270         p9pdu_reset(req->tc);
271         p9pdu_reset(req->rc);
272
273         req->tc->tag = tag-1;
274         req->status = REQ_STATUS_ALLOC;
275
276         return &c->reqs[row][col];
277 }
278
279 /**
280  * p9_tag_lookup - lookup a request by tag
281  * @c: client session to lookup tag within
282  * @tag: numeric id for transaction
283  *
284  */
285
286 struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
287 {
288         int row, col;
289
290         /* This looks up the original request by tag so we know which
291          * buffer to read the data into */
292         tag++;
293
294         if(tag >= c->max_tag) 
295                 return NULL;
296
297         row = tag / P9_ROW_MAXTAG;
298         col = tag % P9_ROW_MAXTAG;
299
300         return &c->reqs[row][col];
301 }
302 EXPORT_SYMBOL(p9_tag_lookup);
303
304 /**
305  * p9_tag_init - setup tags structure and contents
306  * @c:  v9fs client struct
307  *
308  * This initializes the tags structure for each client instance.
309  *
310  */
311
312 static int p9_tag_init(struct p9_client *c)
313 {
314         int err = 0;
315
316         c->tagpool = p9_idpool_create();
317         if (IS_ERR(c->tagpool)) {
318                 err = PTR_ERR(c->tagpool);
319                 goto error;
320         }
321         err = p9_idpool_get(c->tagpool); /* reserve tag 0 */
322         if (err < 0) {
323                 p9_idpool_destroy(c->tagpool);
324                 goto error;
325         }
326         c->max_tag = 0;
327 error:
328         return err;
329 }
330
331 /**
332  * p9_tag_cleanup - cleans up tags structure and reclaims resources
333  * @c:  v9fs client struct
334  *
335  * This frees resources associated with the tags structure
336  *
337  */
338 static void p9_tag_cleanup(struct p9_client *c)
339 {
340         int row, col;
341
342         /* check to insure all requests are idle */
343         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
344                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
345                         if (c->reqs[row][col].status != REQ_STATUS_IDLE) {
346                                 P9_DPRINTK(P9_DEBUG_MUX,
347                                   "Attempting to cleanup non-free tag %d,%d\n",
348                                   row, col);
349                                 /* TODO: delay execution of cleanup */
350                                 return;
351                         }
352                 }
353         }
354
355         if (c->tagpool) {
356                 p9_idpool_put(0, c->tagpool); /* free reserved tag 0 */
357                 p9_idpool_destroy(c->tagpool);
358         }
359
360         /* free requests associated with tags */
361         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
362                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
363                         kfree(c->reqs[row][col].wq);
364                         kfree(c->reqs[row][col].tc);
365                         kfree(c->reqs[row][col].rc);
366                 }
367                 kfree(c->reqs[row]);
368         }
369         c->max_tag = 0;
370 }
371
372 /**
373  * p9_free_req - free a request and clean-up as necessary
374  * c: client state
375  * r: request to release
376  *
377  */
378
379 static void p9_free_req(struct p9_client *c, struct p9_req_t *r)
380 {
381         int tag = r->tc->tag;
382         P9_DPRINTK(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);
383
384         r->status = REQ_STATUS_IDLE;
385         if (tag != P9_NOTAG && p9_idpool_check(tag, c->tagpool))
386                 p9_idpool_put(tag, c->tagpool);
387 }
388
389 /**
390  * p9_client_cb - call back from transport to client
391  * c: client state
392  * req: request received
393  *
394  */
395 void p9_client_cb(struct p9_client *c, struct p9_req_t *req)
396 {
397         P9_DPRINTK(P9_DEBUG_MUX, " tag %d\n", req->tc->tag);
398         wake_up(req->wq);
399         P9_DPRINTK(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
400 }
401 EXPORT_SYMBOL(p9_client_cb);
402
403 /**
404  * p9_parse_header - parse header arguments out of a packet
405  * @pdu: packet to parse
406  * @size: size of packet
407  * @type: type of request
408  * @tag: tag of packet
409  * @rewind: set if we need to rewind offset afterwards
410  */
411
412 int
413 p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
414                                                                 int rewind)
415 {
416         int8_t r_type;
417         int16_t r_tag;
418         int32_t r_size;
419         int offset = pdu->offset;
420         int err;
421
422         pdu->offset = 0;
423         if (pdu->size == 0)
424                 pdu->size = 7;
425
426         err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
427         if (err)
428                 goto rewind_and_exit;
429
430         pdu->size = r_size;
431         pdu->id = r_type;
432         pdu->tag = r_tag;
433
434         P9_DPRINTK(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n", pdu->size,
435                                                         pdu->id, pdu->tag);
436
437         if (type)
438                 *type = r_type;
439         if (tag)
440                 *tag = r_tag;
441         if (size)
442                 *size = r_size;
443
444
445 rewind_and_exit:
446         if (rewind)
447                 pdu->offset = offset;
448         return err;
449 }
450 EXPORT_SYMBOL(p9_parse_header);
451
452 /**
453  * p9_check_errors - check 9p packet for error return and process it
454  * @c: current client instance
455  * @req: request to parse and check for error conditions
456  *
457  * returns error code if one is discovered, otherwise returns 0
458  *
459  * this will have to be more complicated if we have multiple
460  * error packet types
461  */
462
463 static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
464 {
465         int8_t type;
466         int err;
467         int ecode;
468
469         err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
470         /*
471          * dump the response from server
472          * This should be after check errors which poplulate pdu_fcall.
473          */
474         trace_9p_protocol_dump(c, req->rc);
475         if (err) {
476                 P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
477                 return err;
478         }
479         if (type != P9_RERROR && type != P9_RLERROR)
480                 return 0;
481
482         if (!p9_is_proto_dotl(c)) {
483                 char *ename;
484                 err = p9pdu_readf(req->rc, c->proto_version, "s?d",
485                                   &ename, &ecode);
486                 if (err)
487                         goto out_err;
488
489                 if (p9_is_proto_dotu(c))
490                         err = -ecode;
491
492                 if (!err || !IS_ERR_VALUE(err)) {
493                         err = p9_errstr2errno(ename, strlen(ename));
494
495                         P9_DPRINTK(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
496                                    -ecode, ename);
497                 }
498                 kfree(ename);
499         } else {
500                 err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
501                 err = -ecode;
502
503                 P9_DPRINTK(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
504         }
505
506         return err;
507
508 out_err:
509         P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
510
511         return err;
512 }
513
514 /**
515  * p9_check_zc_errors - check 9p packet for error return and process it
516  * @c: current client instance
517  * @req: request to parse and check for error conditions
518  * @in_hdrlen: Size of response protocol buffer.
519  *
520  * returns error code if one is discovered, otherwise returns 0
521  *
522  * this will have to be more complicated if we have multiple
523  * error packet types
524  */
525
526 static int p9_check_zc_errors(struct p9_client *c, struct p9_req_t *req,
527                               char *uidata, int in_hdrlen, int kern_buf)
528 {
529         int err;
530         int ecode;
531         int8_t type;
532         char *ename = NULL;
533
534         err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
535         /*
536          * dump the response from server
537          * This should be after parse_header which poplulate pdu_fcall.
538          */
539         trace_9p_protocol_dump(c, req->rc);
540         if (err) {
541                 P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
542                 return err;
543         }
544
545         if (type != P9_RERROR && type != P9_RLERROR)
546                 return 0;
547
548         if (!p9_is_proto_dotl(c)) {
549                 /* Error is reported in string format */
550                 uint16_t len;
551                 /* 7 = header size for RERROR, 2 is the size of string len; */
552                 int inline_len = in_hdrlen - (7 + 2);
553
554                 /* Read the size of error string */
555                 err = p9pdu_readf(req->rc, c->proto_version, "w", &len);
556                 if (err)
557                         goto out_err;
558
559                 ename = kmalloc(len + 1, GFP_NOFS);
560                 if (!ename) {
561                         err = -ENOMEM;
562                         goto out_err;
563                 }
564                 if (len <= inline_len) {
565                         /* We have error in protocol buffer itself */
566                         if (pdu_read(req->rc, ename, len)) {
567                                 err = -EFAULT;
568                                 goto out_free;
569
570                         }
571                 } else {
572                         /*
573                          *  Part of the data is in user space buffer.
574                          */
575                         if (pdu_read(req->rc, ename, inline_len)) {
576                                 err = -EFAULT;
577                                 goto out_free;
578
579                         }
580                         if (kern_buf) {
581                                 memcpy(ename + inline_len, uidata,
582                                        len - inline_len);
583                         } else {
584                                 err = copy_from_user(ename + inline_len,
585                                                      uidata, len - inline_len);
586                                 if (err) {
587                                         err = -EFAULT;
588                                         goto out_free;
589                                 }
590                         }
591                 }
592                 ename[len] = 0;
593                 if (p9_is_proto_dotu(c)) {
594                         /* For dotu we also have error code */
595                         err = p9pdu_readf(req->rc,
596                                           c->proto_version, "d", &ecode);
597                         if (err)
598                                 goto out_free;
599                         err = -ecode;
600                 }
601                 if (!err || !IS_ERR_VALUE(err)) {
602                         err = p9_errstr2errno(ename, strlen(ename));
603
604                         P9_DPRINTK(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
605                                    -ecode, ename);
606                 }
607                 kfree(ename);
608         } else {
609                 err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
610                 err = -ecode;
611
612                 P9_DPRINTK(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
613         }
614         return err;
615
616 out_free:
617         kfree(ename);
618 out_err:
619         P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
620         return err;
621 }
622
623 static struct p9_req_t *
624 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
625
626 /**
627  * p9_client_flush - flush (cancel) a request
628  * @c: client state
629  * @oldreq: request to cancel
630  *
631  * This sents a flush for a particular request and links
632  * the flush request to the original request.  The current
633  * code only supports a single flush request although the protocol
634  * allows for multiple flush requests to be sent for a single request.
635  *
636  */
637
638 static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
639 {
640         struct p9_req_t *req;
641         int16_t oldtag;
642         int err;
643
644         err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
645         if (err)
646                 return err;
647
648         P9_DPRINTK(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
649
650         req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
651         if (IS_ERR(req))
652                 return PTR_ERR(req);
653
654
655         /* if we haven't received a response for oldreq,
656            remove it from the list. */
657         spin_lock(&c->lock);
658         if (oldreq->status == REQ_STATUS_FLSH)
659                 list_del(&oldreq->req_list);
660         spin_unlock(&c->lock);
661
662         p9_free_req(c, req);
663         return 0;
664 }
665
666 static struct p9_req_t *p9_client_prepare_req(struct p9_client *c,
667                                               int8_t type, int req_size,
668                                               const char *fmt, va_list ap)
669 {
670         int tag, err;
671         struct p9_req_t *req;
672
673         P9_DPRINTK(P9_DEBUG_MUX, "client %p op %d\n", c, type);
674
675         /* we allow for any status other than disconnected */
676         if (c->status == Disconnected)
677                 return ERR_PTR(-EIO);
678
679         /* if status is begin_disconnected we allow only clunk request */
680         if ((c->status == BeginDisconnect) && (type != P9_TCLUNK))
681                 return ERR_PTR(-EIO);
682
683         tag = P9_NOTAG;
684         if (type != P9_TVERSION) {
685                 tag = p9_idpool_get(c->tagpool);
686                 if (tag < 0)
687                         return ERR_PTR(-ENOMEM);
688         }
689
690         req = p9_tag_alloc(c, tag, req_size);
691         if (IS_ERR(req))
692                 return req;
693
694         /* marshall the data */
695         p9pdu_prepare(req->tc, tag, type);
696         err = p9pdu_vwritef(req->tc, c->proto_version, fmt, ap);
697         if (err)
698                 goto reterr;
699         p9pdu_finalize(c, req->tc);
700         trace_9p_client_req(c, type, tag);
701         return req;
702 reterr:
703         p9_free_req(c, req);
704         return ERR_PTR(err);
705 }
706
707 /**
708  * p9_client_rpc - issue a request and wait for a response
709  * @c: client session
710  * @type: type of request
711  * @fmt: protocol format string (see protocol.c)
712  *
713  * Returns request structure (which client must free using p9_free_req)
714  */
715
716 static struct p9_req_t *
717 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
718 {
719         va_list ap;
720         int sigpending, err;
721         unsigned long flags;
722         struct p9_req_t *req;
723
724         va_start(ap, fmt);
725         req = p9_client_prepare_req(c, type, c->msize, fmt, ap);
726         va_end(ap);
727         if (IS_ERR(req))
728                 return req;
729
730         if (signal_pending(current)) {
731                 sigpending = 1;
732                 clear_thread_flag(TIF_SIGPENDING);
733         } else
734                 sigpending = 0;
735
736         err = c->trans_mod->request(c, req);
737         if (err < 0) {
738                 if (err != -ERESTARTSYS && err != -EFAULT)
739                         c->status = Disconnected;
740                 goto reterr;
741         }
742         /* Wait for the response */
743         err = wait_event_interruptible(*req->wq,
744                                        req->status >= REQ_STATUS_RCVD);
745
746         if (req->status == REQ_STATUS_ERROR) {
747                 P9_DPRINTK(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
748                 err = req->t_err;
749         }
750         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
751                 P9_DPRINTK(P9_DEBUG_MUX, "flushing\n");
752                 sigpending = 1;
753                 clear_thread_flag(TIF_SIGPENDING);
754
755                 if (c->trans_mod->cancel(c, req))
756                         p9_client_flush(c, req);
757
758                 /* if we received the response anyway, don't signal error */
759                 if (req->status == REQ_STATUS_RCVD)
760                         err = 0;
761         }
762         if (sigpending) {
763                 spin_lock_irqsave(&current->sighand->siglock, flags);
764                 recalc_sigpending();
765                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
766         }
767         if (err < 0)
768                 goto reterr;
769
770         err = p9_check_errors(c, req);
771         trace_9p_client_res(c, type, req->rc->tag, err);
772         if (!err)
773                 return req;
774 reterr:
775         p9_free_req(c, req);
776         return ERR_PTR(err);
777 }
778
779 /**
780  * p9_client_zc_rpc - issue a request and wait for a response
781  * @c: client session
782  * @type: type of request
783  * @uidata: user bffer that should be ued for zero copy read
784  * @uodata: user buffer that shoud be user for zero copy write
785  * @inlen: read buffer size
786  * @olen: write buffer size
787  * @hdrlen: reader header size, This is the size of response protocol data
788  * @fmt: protocol format string (see protocol.c)
789  *
790  * Returns request structure (which client must free using p9_free_req)
791  */
792 static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type,
793                                          char *uidata, char *uodata,
794                                          int inlen, int olen, int in_hdrlen,
795                                          int kern_buf, const char *fmt, ...)
796 {
797         va_list ap;
798         int sigpending, err;
799         unsigned long flags;
800         struct p9_req_t *req;
801
802         va_start(ap, fmt);
803         /*
804          * We allocate a inline protocol data of only 4k bytes.
805          * The actual content is passed in zero-copy fashion.
806          */
807         req = p9_client_prepare_req(c, type, P9_ZC_HDR_SZ, fmt, ap);
808         va_end(ap);
809         if (IS_ERR(req))
810                 return req;
811
812         if (signal_pending(current)) {
813                 sigpending = 1;
814                 clear_thread_flag(TIF_SIGPENDING);
815         } else
816                 sigpending = 0;
817
818         /* If we are called with KERNEL_DS force kern_buf */
819         if (segment_eq(get_fs(), KERNEL_DS))
820                 kern_buf = 1;
821
822         err = c->trans_mod->zc_request(c, req, uidata, uodata,
823                                        inlen, olen, in_hdrlen, kern_buf);
824         if (err < 0) {
825                 if (err == -EIO)
826                         c->status = Disconnected;
827                 goto reterr;
828         }
829         if (req->status == REQ_STATUS_ERROR) {
830                 P9_DPRINTK(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
831                 err = req->t_err;
832         }
833         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
834                 P9_DPRINTK(P9_DEBUG_MUX, "flushing\n");
835                 sigpending = 1;
836                 clear_thread_flag(TIF_SIGPENDING);
837
838                 if (c->trans_mod->cancel(c, req))
839                         p9_client_flush(c, req);
840
841                 /* if we received the response anyway, don't signal error */
842                 if (req->status == REQ_STATUS_RCVD)
843                         err = 0;
844         }
845         if (sigpending) {
846                 spin_lock_irqsave(&current->sighand->siglock, flags);
847                 recalc_sigpending();
848                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
849         }
850         if (err < 0)
851                 goto reterr;
852
853         err = p9_check_zc_errors(c, req, uidata, in_hdrlen, kern_buf);
854         trace_9p_client_res(c, type, req->rc->tag, err);
855         if (!err)
856                 return req;
857 reterr:
858         p9_free_req(c, req);
859         return ERR_PTR(err);
860 }
861
862 static struct p9_fid *p9_fid_create(struct p9_client *clnt)
863 {
864         int ret;
865         struct p9_fid *fid;
866         unsigned long flags;
867
868         P9_DPRINTK(P9_DEBUG_FID, "clnt %p\n", clnt);
869         fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
870         if (!fid)
871                 return ERR_PTR(-ENOMEM);
872
873         ret = p9_idpool_get(clnt->fidpool);
874         if (ret < 0) {
875                 ret = -ENOSPC;
876                 goto error;
877         }
878         fid->fid = ret;
879
880         memset(&fid->qid, 0, sizeof(struct p9_qid));
881         fid->mode = -1;
882         fid->uid = current_fsuid();
883         fid->clnt = clnt;
884         fid->rdir = NULL;
885         spin_lock_irqsave(&clnt->lock, flags);
886         list_add(&fid->flist, &clnt->fidlist);
887         spin_unlock_irqrestore(&clnt->lock, flags);
888
889         return fid;
890
891 error:
892         kfree(fid);
893         return ERR_PTR(ret);
894 }
895
896 static void p9_fid_destroy(struct p9_fid *fid)
897 {
898         struct p9_client *clnt;
899         unsigned long flags;
900
901         P9_DPRINTK(P9_DEBUG_FID, "fid %d\n", fid->fid);
902         clnt = fid->clnt;
903         p9_idpool_put(fid->fid, clnt->fidpool);
904         spin_lock_irqsave(&clnt->lock, flags);
905         list_del(&fid->flist);
906         spin_unlock_irqrestore(&clnt->lock, flags);
907         kfree(fid->rdir);
908         kfree(fid);
909 }
910
911 static int p9_client_version(struct p9_client *c)
912 {
913         int err = 0;
914         struct p9_req_t *req;
915         char *version;
916         int msize;
917
918         P9_DPRINTK(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
919                                                 c->msize, c->proto_version);
920
921         switch (c->proto_version) {
922         case p9_proto_2000L:
923                 req = p9_client_rpc(c, P9_TVERSION, "ds",
924                                         c->msize, "9P2000.L");
925                 break;
926         case p9_proto_2000u:
927                 req = p9_client_rpc(c, P9_TVERSION, "ds",
928                                         c->msize, "9P2000.u");
929                 break;
930         case p9_proto_legacy:
931                 req = p9_client_rpc(c, P9_TVERSION, "ds",
932                                         c->msize, "9P2000");
933                 break;
934         default:
935                 return -EINVAL;
936                 break;
937         }
938
939         if (IS_ERR(req))
940                 return PTR_ERR(req);
941
942         err = p9pdu_readf(req->rc, c->proto_version, "ds", &msize, &version);
943         if (err) {
944                 P9_DPRINTK(P9_DEBUG_9P, "version error %d\n", err);
945                 trace_9p_protocol_dump(c, req->rc);
946                 goto error;
947         }
948
949         P9_DPRINTK(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
950         if (!strncmp(version, "9P2000.L", 8))
951                 c->proto_version = p9_proto_2000L;
952         else if (!strncmp(version, "9P2000.u", 8))
953                 c->proto_version = p9_proto_2000u;
954         else if (!strncmp(version, "9P2000", 6))
955                 c->proto_version = p9_proto_legacy;
956         else {
957                 err = -EREMOTEIO;
958                 goto error;
959         }
960
961         if (msize < c->msize)
962                 c->msize = msize;
963
964 error:
965         kfree(version);
966         p9_free_req(c, req);
967
968         return err;
969 }
970
971 struct p9_client *p9_client_create(const char *dev_name, char *options)
972 {
973         int err;
974         struct p9_client *clnt;
975
976         err = 0;
977         clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
978         if (!clnt)
979                 return ERR_PTR(-ENOMEM);
980
981         clnt->trans_mod = NULL;
982         clnt->trans = NULL;
983         spin_lock_init(&clnt->lock);
984         INIT_LIST_HEAD(&clnt->fidlist);
985
986         err = p9_tag_init(clnt);
987         if (err < 0)
988                 goto free_client;
989
990         err = parse_opts(options, clnt);
991         if (err < 0)
992                 goto destroy_tagpool;
993
994         if (!clnt->trans_mod)
995                 clnt->trans_mod = v9fs_get_default_trans();
996
997         if (clnt->trans_mod == NULL) {
998                 err = -EPROTONOSUPPORT;
999                 P9_DPRINTK(P9_DEBUG_ERROR,
1000                                 "No transport defined or default transport\n");
1001                 goto destroy_tagpool;
1002         }
1003
1004         clnt->fidpool = p9_idpool_create();
1005         if (IS_ERR(clnt->fidpool)) {
1006                 err = PTR_ERR(clnt->fidpool);
1007                 goto put_trans;
1008         }
1009
1010         P9_DPRINTK(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
1011                 clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
1012
1013         err = clnt->trans_mod->create(clnt, dev_name, options);
1014         if (err)
1015                 goto destroy_fidpool;
1016
1017         if (clnt->msize > clnt->trans_mod->maxsize)
1018                 clnt->msize = clnt->trans_mod->maxsize;
1019
1020         err = p9_client_version(clnt);
1021         if (err)
1022                 goto close_trans;
1023
1024         return clnt;
1025
1026 close_trans:
1027         clnt->trans_mod->close(clnt);
1028 destroy_fidpool:
1029         p9_idpool_destroy(clnt->fidpool);
1030 put_trans:
1031         v9fs_put_trans(clnt->trans_mod);
1032 destroy_tagpool:
1033         p9_idpool_destroy(clnt->tagpool);
1034 free_client:
1035         kfree(clnt);
1036         return ERR_PTR(err);
1037 }
1038 EXPORT_SYMBOL(p9_client_create);
1039
1040 void p9_client_destroy(struct p9_client *clnt)
1041 {
1042         struct p9_fid *fid, *fidptr;
1043
1044         P9_DPRINTK(P9_DEBUG_MUX, "clnt %p\n", clnt);
1045
1046         if (clnt->trans_mod)
1047                 clnt->trans_mod->close(clnt);
1048
1049         v9fs_put_trans(clnt->trans_mod);
1050
1051         list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist) {
1052                 printk(KERN_INFO "Found fid %d not clunked\n", fid->fid);
1053                 p9_fid_destroy(fid);
1054         }
1055
1056         if (clnt->fidpool)
1057                 p9_idpool_destroy(clnt->fidpool);
1058
1059         p9_tag_cleanup(clnt);
1060
1061         kfree(clnt);
1062 }
1063 EXPORT_SYMBOL(p9_client_destroy);
1064
1065 void p9_client_disconnect(struct p9_client *clnt)
1066 {
1067         P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
1068         clnt->status = Disconnected;
1069 }
1070 EXPORT_SYMBOL(p9_client_disconnect);
1071
1072 void p9_client_begin_disconnect(struct p9_client *clnt)
1073 {
1074         P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
1075         clnt->status = BeginDisconnect;
1076 }
1077 EXPORT_SYMBOL(p9_client_begin_disconnect);
1078
1079 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
1080         char *uname, u32 n_uname, char *aname)
1081 {
1082         int err = 0;
1083         struct p9_req_t *req;
1084         struct p9_fid *fid;
1085         struct p9_qid qid;
1086
1087
1088         P9_DPRINTK(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
1089                    afid ? afid->fid : -1, uname, aname);
1090         fid = p9_fid_create(clnt);
1091         if (IS_ERR(fid)) {
1092                 err = PTR_ERR(fid);
1093                 fid = NULL;
1094                 goto error;
1095         }
1096
1097         req = p9_client_rpc(clnt, P9_TATTACH, "ddss?d", fid->fid,
1098                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
1099         if (IS_ERR(req)) {
1100                 err = PTR_ERR(req);
1101                 goto error;
1102         }
1103
1104         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
1105         if (err) {
1106                 trace_9p_protocol_dump(clnt, req->rc);
1107                 p9_free_req(clnt, req);
1108                 goto error;
1109         }
1110
1111         P9_DPRINTK(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
1112                                         qid.type,
1113                                         (unsigned long long)qid.path,
1114                                         qid.version);
1115
1116         memmove(&fid->qid, &qid, sizeof(struct p9_qid));
1117
1118         p9_free_req(clnt, req);
1119         return fid;
1120
1121 error:
1122         if (fid)
1123                 p9_fid_destroy(fid);
1124         return ERR_PTR(err);
1125 }
1126 EXPORT_SYMBOL(p9_client_attach);
1127
1128 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
1129                 char **wnames, int clone)
1130 {
1131         int err;
1132         struct p9_client *clnt;
1133         struct p9_fid *fid;
1134         struct p9_qid *wqids;
1135         struct p9_req_t *req;
1136         uint16_t nwqids, count;
1137
1138         err = 0;
1139         wqids = NULL;
1140         clnt = oldfid->clnt;
1141         if (clone) {
1142                 fid = p9_fid_create(clnt);
1143                 if (IS_ERR(fid)) {
1144                         err = PTR_ERR(fid);
1145                         fid = NULL;
1146                         goto error;
1147                 }
1148
1149                 fid->uid = oldfid->uid;
1150         } else
1151                 fid = oldfid;
1152
1153
1154         P9_DPRINTK(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %ud wname[0] %s\n",
1155                 oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
1156
1157         req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
1158                                                                 nwname, wnames);
1159         if (IS_ERR(req)) {
1160                 err = PTR_ERR(req);
1161                 goto error;
1162         }
1163
1164         err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
1165         if (err) {
1166                 trace_9p_protocol_dump(clnt, req->rc);
1167                 p9_free_req(clnt, req);
1168                 goto clunk_fid;
1169         }
1170         p9_free_req(clnt, req);
1171
1172         P9_DPRINTK(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
1173
1174         if (nwqids != nwname) {
1175                 err = -ENOENT;
1176                 goto clunk_fid;
1177         }
1178
1179         for (count = 0; count < nwqids; count++)
1180                 P9_DPRINTK(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
1181                         count, wqids[count].type,
1182                         (unsigned long long)wqids[count].path,
1183                         wqids[count].version);
1184
1185         if (nwname)
1186                 memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
1187         else
1188                 fid->qid = oldfid->qid;
1189
1190         kfree(wqids);
1191         return fid;
1192
1193 clunk_fid:
1194         kfree(wqids);
1195         p9_client_clunk(fid);
1196         fid = NULL;
1197
1198 error:
1199         if (fid && (fid != oldfid))
1200                 p9_fid_destroy(fid);
1201
1202         return ERR_PTR(err);
1203 }
1204 EXPORT_SYMBOL(p9_client_walk);
1205
1206 int p9_client_open(struct p9_fid *fid, int mode)
1207 {
1208         int err;
1209         struct p9_client *clnt;
1210         struct p9_req_t *req;
1211         struct p9_qid qid;
1212         int iounit;
1213
1214         clnt = fid->clnt;
1215         P9_DPRINTK(P9_DEBUG_9P, ">>> %s fid %d mode %d\n",
1216                 p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode);
1217         err = 0;
1218
1219         if (fid->mode != -1)
1220                 return -EINVAL;
1221
1222         if (p9_is_proto_dotl(clnt))
1223                 req = p9_client_rpc(clnt, P9_TLOPEN, "dd", fid->fid, mode);
1224         else
1225                 req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
1226         if (IS_ERR(req)) {
1227                 err = PTR_ERR(req);
1228                 goto error;
1229         }
1230
1231         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1232         if (err) {
1233                 trace_9p_protocol_dump(clnt, req->rc);
1234                 goto free_and_error;
1235         }
1236
1237         P9_DPRINTK(P9_DEBUG_9P, "<<< %s qid %x.%llx.%x iounit %x\n",
1238                 p9_is_proto_dotl(clnt) ? "RLOPEN" : "ROPEN",  qid.type,
1239                 (unsigned long long)qid.path, qid.version, iounit);
1240
1241         fid->mode = mode;
1242         fid->iounit = iounit;
1243
1244 free_and_error:
1245         p9_free_req(clnt, req);
1246 error:
1247         return err;
1248 }
1249 EXPORT_SYMBOL(p9_client_open);
1250
1251 int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode,
1252                 gid_t gid, struct p9_qid *qid)
1253 {
1254         int err = 0;
1255         struct p9_client *clnt;
1256         struct p9_req_t *req;
1257         int iounit;
1258
1259         P9_DPRINTK(P9_DEBUG_9P,
1260                         ">>> TLCREATE fid %d name %s flags %d mode %d gid %d\n",
1261                         ofid->fid, name, flags, mode, gid);
1262         clnt = ofid->clnt;
1263
1264         if (ofid->mode != -1)
1265                 return -EINVAL;
1266
1267         req = p9_client_rpc(clnt, P9_TLCREATE, "dsddd", ofid->fid, name, flags,
1268                         mode, gid);
1269         if (IS_ERR(req)) {
1270                 err = PTR_ERR(req);
1271                 goto error;
1272         }
1273
1274         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", qid, &iounit);
1275         if (err) {
1276                 trace_9p_protocol_dump(clnt, req->rc);
1277                 goto free_and_error;
1278         }
1279
1280         P9_DPRINTK(P9_DEBUG_9P, "<<< RLCREATE qid %x.%llx.%x iounit %x\n",
1281                         qid->type,
1282                         (unsigned long long)qid->path,
1283                         qid->version, iounit);
1284
1285         ofid->mode = mode;
1286         ofid->iounit = iounit;
1287
1288 free_and_error:
1289         p9_free_req(clnt, req);
1290 error:
1291         return err;
1292 }
1293 EXPORT_SYMBOL(p9_client_create_dotl);
1294
1295 int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
1296                      char *extension)
1297 {
1298         int err;
1299         struct p9_client *clnt;
1300         struct p9_req_t *req;
1301         struct p9_qid qid;
1302         int iounit;
1303
1304         P9_DPRINTK(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1305                                                 fid->fid, name, perm, mode);
1306         err = 0;
1307         clnt = fid->clnt;
1308
1309         if (fid->mode != -1)
1310                 return -EINVAL;
1311
1312         req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1313                                 mode, extension);
1314         if (IS_ERR(req)) {
1315                 err = PTR_ERR(req);
1316                 goto error;
1317         }
1318
1319         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1320         if (err) {
1321                 trace_9p_protocol_dump(clnt, req->rc);
1322                 goto free_and_error;
1323         }
1324
1325         P9_DPRINTK(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1326                                 qid.type,
1327                                 (unsigned long long)qid.path,
1328                                 qid.version, iounit);
1329
1330         fid->mode = mode;
1331         fid->iounit = iounit;
1332
1333 free_and_error:
1334         p9_free_req(clnt, req);
1335 error:
1336         return err;
1337 }
1338 EXPORT_SYMBOL(p9_client_fcreate);
1339
1340 int p9_client_symlink(struct p9_fid *dfid, char *name, char *symtgt, gid_t gid,
1341                 struct p9_qid *qid)
1342 {
1343         int err = 0;
1344         struct p9_client *clnt;
1345         struct p9_req_t *req;
1346
1347         P9_DPRINTK(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s  symtgt %s\n",
1348                         dfid->fid, name, symtgt);
1349         clnt = dfid->clnt;
1350
1351         req = p9_client_rpc(clnt, P9_TSYMLINK, "dssd", dfid->fid, name, symtgt,
1352                         gid);
1353         if (IS_ERR(req)) {
1354                 err = PTR_ERR(req);
1355                 goto error;
1356         }
1357
1358         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1359         if (err) {
1360                 trace_9p_protocol_dump(clnt, req->rc);
1361                 goto free_and_error;
1362         }
1363
1364         P9_DPRINTK(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n",
1365                         qid->type, (unsigned long long)qid->path, qid->version);
1366
1367 free_and_error:
1368         p9_free_req(clnt, req);
1369 error:
1370         return err;
1371 }
1372 EXPORT_SYMBOL(p9_client_symlink);
1373
1374 int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, char *newname)
1375 {
1376         struct p9_client *clnt;
1377         struct p9_req_t *req;
1378
1379         P9_DPRINTK(P9_DEBUG_9P, ">>> TLINK dfid %d oldfid %d newname %s\n",
1380                         dfid->fid, oldfid->fid, newname);
1381         clnt = dfid->clnt;
1382         req = p9_client_rpc(clnt, P9_TLINK, "dds", dfid->fid, oldfid->fid,
1383                         newname);
1384         if (IS_ERR(req))
1385                 return PTR_ERR(req);
1386
1387         P9_DPRINTK(P9_DEBUG_9P, "<<< RLINK\n");
1388         p9_free_req(clnt, req);
1389         return 0;
1390 }
1391 EXPORT_SYMBOL(p9_client_link);
1392
1393 int p9_client_fsync(struct p9_fid *fid, int datasync)
1394 {
1395         int err;
1396         struct p9_client *clnt;
1397         struct p9_req_t *req;
1398
1399         P9_DPRINTK(P9_DEBUG_9P, ">>> TFSYNC fid %d datasync:%d\n",
1400                         fid->fid, datasync);
1401         err = 0;
1402         clnt = fid->clnt;
1403
1404         req = p9_client_rpc(clnt, P9_TFSYNC, "dd", fid->fid, datasync);
1405         if (IS_ERR(req)) {
1406                 err = PTR_ERR(req);
1407                 goto error;
1408         }
1409
1410         P9_DPRINTK(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid);
1411
1412         p9_free_req(clnt, req);
1413
1414 error:
1415         return err;
1416 }
1417 EXPORT_SYMBOL(p9_client_fsync);
1418
1419 int p9_client_clunk(struct p9_fid *fid)
1420 {
1421         int err;
1422         struct p9_client *clnt;
1423         struct p9_req_t *req;
1424
1425         if (!fid) {
1426                 P9_EPRINTK(KERN_WARNING, "Trying to clunk with NULL fid\n");
1427                 dump_stack();
1428                 return 0;
1429         }
1430
1431         P9_DPRINTK(P9_DEBUG_9P, ">>> TCLUNK fid %d\n", fid->fid);
1432         err = 0;
1433         clnt = fid->clnt;
1434
1435         req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1436         if (IS_ERR(req)) {
1437                 err = PTR_ERR(req);
1438                 goto error;
1439         }
1440
1441         P9_DPRINTK(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1442
1443         p9_free_req(clnt, req);
1444 error:
1445         /*
1446          * Fid is not valid even after a failed clunk
1447          */
1448         p9_fid_destroy(fid);
1449         return err;
1450 }
1451 EXPORT_SYMBOL(p9_client_clunk);
1452
1453 int p9_client_remove(struct p9_fid *fid)
1454 {
1455         int err;
1456         struct p9_client *clnt;
1457         struct p9_req_t *req;
1458
1459         P9_DPRINTK(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1460         err = 0;
1461         clnt = fid->clnt;
1462
1463         req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1464         if (IS_ERR(req)) {
1465                 err = PTR_ERR(req);
1466                 goto error;
1467         }
1468
1469         P9_DPRINTK(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1470
1471         p9_free_req(clnt, req);
1472 error:
1473         p9_fid_destroy(fid);
1474         return err;
1475 }
1476 EXPORT_SYMBOL(p9_client_remove);
1477
1478 int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags)
1479 {
1480         int err = 0;
1481         struct p9_req_t *req;
1482         struct p9_client *clnt;
1483
1484         P9_DPRINTK(P9_DEBUG_9P, ">>> TUNLINKAT fid %d %s %d\n",
1485                    dfid->fid, name, flags);
1486
1487         clnt = dfid->clnt;
1488         req = p9_client_rpc(clnt, P9_TUNLINKAT, "dsd", dfid->fid, name, flags);
1489         if (IS_ERR(req)) {
1490                 err = PTR_ERR(req);
1491                 goto error;
1492         }
1493         P9_DPRINTK(P9_DEBUG_9P, "<<< RUNLINKAT fid %d %s\n", dfid->fid, name);
1494
1495         p9_free_req(clnt, req);
1496 error:
1497         return err;
1498 }
1499 EXPORT_SYMBOL(p9_client_unlinkat);
1500
1501 int
1502 p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
1503                                                                 u32 count)
1504 {
1505         char *dataptr;
1506         int kernel_buf = 0;
1507         struct p9_req_t *req;
1508         struct p9_client *clnt;
1509         int err, rsize, non_zc = 0;
1510
1511
1512         P9_DPRINTK(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n",
1513                    fid->fid, (long long unsigned) offset, count);
1514         err = 0;
1515         clnt = fid->clnt;
1516
1517         rsize = fid->iounit;
1518         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1519                 rsize = clnt->msize - P9_IOHDRSZ;
1520
1521         if (count < rsize)
1522                 rsize = count;
1523
1524         /* Don't bother zerocopy for small IO (< 1024) */
1525         if (clnt->trans_mod->zc_request && rsize > 1024) {
1526                 char *indata;
1527                 if (data) {
1528                         kernel_buf = 1;
1529                         indata = data;
1530                 } else
1531                         indata = (char *)udata;
1532                 /*
1533                  * response header len is 11
1534                  * PDU Header(7) + IO Size (4)
1535                  */
1536                 req = p9_client_zc_rpc(clnt, P9_TREAD, indata, NULL, rsize, 0,
1537                                        11, kernel_buf, "dqd", fid->fid,
1538                                        offset, rsize);
1539         } else {
1540                 non_zc = 1;
1541                 req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset,
1542                                     rsize);
1543         }
1544         if (IS_ERR(req)) {
1545                 err = PTR_ERR(req);
1546                 goto error;
1547         }
1548
1549         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
1550         if (err) {
1551                 trace_9p_protocol_dump(clnt, req->rc);
1552                 goto free_and_error;
1553         }
1554
1555         P9_DPRINTK(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1556
1557         if (non_zc) {
1558                 if (data) {
1559                         memmove(data, dataptr, count);
1560                 } else {
1561                         err = copy_to_user(udata, dataptr, count);
1562                         if (err) {
1563                                 err = -EFAULT;
1564                                 goto free_and_error;
1565                         }
1566                 }
1567         }
1568         p9_free_req(clnt, req);
1569         return count;
1570
1571 free_and_error:
1572         p9_free_req(clnt, req);
1573 error:
1574         return err;
1575 }
1576 EXPORT_SYMBOL(p9_client_read);
1577
1578 int
1579 p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
1580                                                         u64 offset, u32 count)
1581 {
1582         int err, rsize;
1583         int kernel_buf = 0;
1584         struct p9_client *clnt;
1585         struct p9_req_t *req;
1586
1587         P9_DPRINTK(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d\n",
1588                                 fid->fid, (long long unsigned) offset, count);
1589         err = 0;
1590         clnt = fid->clnt;
1591
1592         rsize = fid->iounit;
1593         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1594                 rsize = clnt->msize - P9_IOHDRSZ;
1595
1596         if (count < rsize)
1597                 rsize = count;
1598
1599         /* Don't bother zerocopy for small IO (< 1024) */
1600         if (clnt->trans_mod->zc_request && rsize > 1024) {
1601                 char *odata;
1602                 if (data) {
1603                         kernel_buf = 1;
1604                         odata = data;
1605                 } else
1606                         odata = (char *)udata;
1607                 req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, odata, 0, rsize,
1608                                        P9_ZC_HDR_SZ, kernel_buf, "dqd",
1609                                        fid->fid, offset, rsize);
1610         } else {
1611                 if (data)
1612                         req = p9_client_rpc(clnt, P9_TWRITE, "dqD", fid->fid,
1613                                             offset, rsize, data);
1614                 else
1615                         req = p9_client_rpc(clnt, P9_TWRITE, "dqU", fid->fid,
1616                                             offset, rsize, udata);
1617         }
1618         if (IS_ERR(req)) {
1619                 err = PTR_ERR(req);
1620                 goto error;
1621         }
1622
1623         err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1624         if (err) {
1625                 trace_9p_protocol_dump(clnt, req->rc);
1626                 goto free_and_error;
1627         }
1628
1629         P9_DPRINTK(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1630
1631         p9_free_req(clnt, req);
1632         return count;
1633
1634 free_and_error:
1635         p9_free_req(clnt, req);
1636 error:
1637         return err;
1638 }
1639 EXPORT_SYMBOL(p9_client_write);
1640
1641 struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1642 {
1643         int err;
1644         struct p9_client *clnt;
1645         struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1646         struct p9_req_t *req;
1647         u16 ignored;
1648
1649         P9_DPRINTK(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1650
1651         if (!ret)
1652                 return ERR_PTR(-ENOMEM);
1653
1654         err = 0;
1655         clnt = fid->clnt;
1656
1657         req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1658         if (IS_ERR(req)) {
1659                 err = PTR_ERR(req);
1660                 goto error;
1661         }
1662
1663         err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1664         if (err) {
1665                 trace_9p_protocol_dump(clnt, req->rc);
1666                 p9_free_req(clnt, req);
1667                 goto error;
1668         }
1669
1670         P9_DPRINTK(P9_DEBUG_9P,
1671                 "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1672                 "<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1673                 "<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1674                 "<<<    uid=%d gid=%d n_muid=%d\n",
1675                 ret->size, ret->type, ret->dev, ret->qid.type,
1676                 (unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1677                 ret->atime, ret->mtime, (unsigned long long)ret->length,
1678                 ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1679                 ret->n_uid, ret->n_gid, ret->n_muid);
1680
1681         p9_free_req(clnt, req);
1682         return ret;
1683
1684 error:
1685         kfree(ret);
1686         return ERR_PTR(err);
1687 }
1688 EXPORT_SYMBOL(p9_client_stat);
1689
1690 struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
1691                                                         u64 request_mask)
1692 {
1693         int err;
1694         struct p9_client *clnt;
1695         struct p9_stat_dotl *ret = kmalloc(sizeof(struct p9_stat_dotl),
1696                                                                 GFP_KERNEL);
1697         struct p9_req_t *req;
1698
1699         P9_DPRINTK(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n",
1700                                                         fid->fid, request_mask);
1701
1702         if (!ret)
1703                 return ERR_PTR(-ENOMEM);
1704
1705         err = 0;
1706         clnt = fid->clnt;
1707
1708         req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
1709         if (IS_ERR(req)) {
1710                 err = PTR_ERR(req);
1711                 goto error;
1712         }
1713
1714         err = p9pdu_readf(req->rc, clnt->proto_version, "A", ret);
1715         if (err) {
1716                 trace_9p_protocol_dump(clnt, req->rc);
1717                 p9_free_req(clnt, req);
1718                 goto error;
1719         }
1720
1721         P9_DPRINTK(P9_DEBUG_9P,
1722                 "<<< RGETATTR st_result_mask=%lld\n"
1723                 "<<< qid=%x.%llx.%x\n"
1724                 "<<< st_mode=%8.8x st_nlink=%llu\n"
1725                 "<<< st_uid=%d st_gid=%d\n"
1726                 "<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n"
1727                 "<<< st_atime_sec=%lld st_atime_nsec=%lld\n"
1728                 "<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n"
1729                 "<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n"
1730                 "<<< st_btime_sec=%lld st_btime_nsec=%lld\n"
1731                 "<<< st_gen=%lld st_data_version=%lld",
1732                 ret->st_result_mask, ret->qid.type, ret->qid.path,
1733                 ret->qid.version, ret->st_mode, ret->st_nlink, ret->st_uid,
1734                 ret->st_gid, ret->st_rdev, ret->st_size, ret->st_blksize,
1735                 ret->st_blocks, ret->st_atime_sec, ret->st_atime_nsec,
1736                 ret->st_mtime_sec, ret->st_mtime_nsec, ret->st_ctime_sec,
1737                 ret->st_ctime_nsec, ret->st_btime_sec, ret->st_btime_nsec,
1738                 ret->st_gen, ret->st_data_version);
1739
1740         p9_free_req(clnt, req);
1741         return ret;
1742
1743 error:
1744         kfree(ret);
1745         return ERR_PTR(err);
1746 }
1747 EXPORT_SYMBOL(p9_client_getattr_dotl);
1748
1749 static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1750 {
1751         int ret;
1752
1753         /* NOTE: size shouldn't include its own length */
1754         /* size[2] type[2] dev[4] qid[13] */
1755         /* mode[4] atime[4] mtime[4] length[8]*/
1756         /* name[s] uid[s] gid[s] muid[s] */
1757         ret = 2+4+13+4+4+4+8+2+2+2+2;
1758
1759         if (wst->name)
1760                 ret += strlen(wst->name);
1761         if (wst->uid)
1762                 ret += strlen(wst->uid);
1763         if (wst->gid)
1764                 ret += strlen(wst->gid);
1765         if (wst->muid)
1766                 ret += strlen(wst->muid);
1767
1768         if ((proto_version == p9_proto_2000u) ||
1769                 (proto_version == p9_proto_2000L)) {
1770                 ret += 2+4+4+4; /* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1771                 if (wst->extension)
1772                         ret += strlen(wst->extension);
1773         }
1774
1775         return ret;
1776 }
1777
1778 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1779 {
1780         int err;
1781         struct p9_req_t *req;
1782         struct p9_client *clnt;
1783
1784         err = 0;
1785         clnt = fid->clnt;
1786         wst->size = p9_client_statsize(wst, clnt->proto_version);
1787         P9_DPRINTK(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1788         P9_DPRINTK(P9_DEBUG_9P,
1789                 "     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1790                 "     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1791                 "     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1792                 "     uid=%d gid=%d n_muid=%d\n",
1793                 wst->size, wst->type, wst->dev, wst->qid.type,
1794                 (unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1795                 wst->atime, wst->mtime, (unsigned long long)wst->length,
1796                 wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1797                 wst->n_uid, wst->n_gid, wst->n_muid);
1798
1799         req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1800         if (IS_ERR(req)) {
1801                 err = PTR_ERR(req);
1802                 goto error;
1803         }
1804
1805         P9_DPRINTK(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1806
1807         p9_free_req(clnt, req);
1808 error:
1809         return err;
1810 }
1811 EXPORT_SYMBOL(p9_client_wstat);
1812
1813 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
1814 {
1815         int err;
1816         struct p9_req_t *req;
1817         struct p9_client *clnt;
1818
1819         err = 0;
1820         clnt = fid->clnt;
1821         P9_DPRINTK(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
1822         P9_DPRINTK(P9_DEBUG_9P,
1823                 "    valid=%x mode=%x uid=%d gid=%d size=%lld\n"
1824                 "    atime_sec=%lld atime_nsec=%lld\n"
1825                 "    mtime_sec=%lld mtime_nsec=%lld\n",
1826                 p9attr->valid, p9attr->mode, p9attr->uid, p9attr->gid,
1827                 p9attr->size, p9attr->atime_sec, p9attr->atime_nsec,
1828                 p9attr->mtime_sec, p9attr->mtime_nsec);
1829
1830         req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr);
1831
1832         if (IS_ERR(req)) {
1833                 err = PTR_ERR(req);
1834                 goto error;
1835         }
1836         P9_DPRINTK(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);
1837         p9_free_req(clnt, req);
1838 error:
1839         return err;
1840 }
1841 EXPORT_SYMBOL(p9_client_setattr);
1842
1843 int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
1844 {
1845         int err;
1846         struct p9_req_t *req;
1847         struct p9_client *clnt;
1848
1849         err = 0;
1850         clnt = fid->clnt;
1851
1852         P9_DPRINTK(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
1853
1854         req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
1855         if (IS_ERR(req)) {
1856                 err = PTR_ERR(req);
1857                 goto error;
1858         }
1859
1860         err = p9pdu_readf(req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
1861                 &sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
1862                 &sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
1863         if (err) {
1864                 trace_9p_protocol_dump(clnt, req->rc);
1865                 p9_free_req(clnt, req);
1866                 goto error;
1867         }
1868
1869         P9_DPRINTK(P9_DEBUG_9P, "<<< RSTATFS fid %d type 0x%lx bsize %ld "
1870                 "blocks %llu bfree %llu bavail %llu files %llu ffree %llu "
1871                 "fsid %llu namelen %ld\n",
1872                 fid->fid, (long unsigned int)sb->type, (long int)sb->bsize,
1873                 sb->blocks, sb->bfree, sb->bavail, sb->files,  sb->ffree,
1874                 sb->fsid, (long int)sb->namelen);
1875
1876         p9_free_req(clnt, req);
1877 error:
1878         return err;
1879 }
1880 EXPORT_SYMBOL(p9_client_statfs);
1881
1882 int p9_client_rename(struct p9_fid *fid,
1883                      struct p9_fid *newdirfid, const char *name)
1884 {
1885         int err;
1886         struct p9_req_t *req;
1887         struct p9_client *clnt;
1888
1889         err = 0;
1890         clnt = fid->clnt;
1891
1892         P9_DPRINTK(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
1893                         fid->fid, newdirfid->fid, name);
1894
1895         req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid,
1896                         newdirfid->fid, name);
1897         if (IS_ERR(req)) {
1898                 err = PTR_ERR(req);
1899                 goto error;
1900         }
1901
1902         P9_DPRINTK(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);
1903
1904         p9_free_req(clnt, req);
1905 error:
1906         return err;
1907 }
1908 EXPORT_SYMBOL(p9_client_rename);
1909
1910 int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
1911                        struct p9_fid *newdirfid, const char *new_name)
1912 {
1913         int err;
1914         struct p9_req_t *req;
1915         struct p9_client *clnt;
1916
1917         err = 0;
1918         clnt = olddirfid->clnt;
1919
1920         P9_DPRINTK(P9_DEBUG_9P, ">>> TRENAMEAT olddirfid %d old name %s"
1921                    " newdirfid %d new name %s\n", olddirfid->fid, old_name,
1922                    newdirfid->fid, new_name);
1923
1924         req = p9_client_rpc(clnt, P9_TRENAMEAT, "dsds", olddirfid->fid,
1925                             old_name, newdirfid->fid, new_name);
1926         if (IS_ERR(req)) {
1927                 err = PTR_ERR(req);
1928                 goto error;
1929         }
1930
1931         P9_DPRINTK(P9_DEBUG_9P, "<<< RRENAMEAT newdirfid %d new name %s\n",
1932                    newdirfid->fid, new_name);
1933
1934         p9_free_req(clnt, req);
1935 error:
1936         return err;
1937 }
1938 EXPORT_SYMBOL(p9_client_renameat);
1939
1940 /*
1941  * An xattrwalk without @attr_name gives the fid for the lisxattr namespace
1942  */
1943 struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
1944                                 const char *attr_name, u64 *attr_size)
1945 {
1946         int err;
1947         struct p9_req_t *req;
1948         struct p9_client *clnt;
1949         struct p9_fid *attr_fid;
1950
1951         err = 0;
1952         clnt = file_fid->clnt;
1953         attr_fid = p9_fid_create(clnt);
1954         if (IS_ERR(attr_fid)) {
1955                 err = PTR_ERR(attr_fid);
1956                 attr_fid = NULL;
1957                 goto error;
1958         }
1959         P9_DPRINTK(P9_DEBUG_9P,
1960                 ">>> TXATTRWALK file_fid %d, attr_fid %d name %s\n",
1961                 file_fid->fid, attr_fid->fid, attr_name);
1962
1963         req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds",
1964                         file_fid->fid, attr_fid->fid, attr_name);
1965         if (IS_ERR(req)) {
1966                 err = PTR_ERR(req);
1967                 goto error;
1968         }
1969         err = p9pdu_readf(req->rc, clnt->proto_version, "q", attr_size);
1970         if (err) {
1971                 trace_9p_protocol_dump(clnt, req->rc);
1972                 p9_free_req(clnt, req);
1973                 goto clunk_fid;
1974         }
1975         p9_free_req(clnt, req);
1976         P9_DPRINTK(P9_DEBUG_9P, "<<<  RXATTRWALK fid %d size %llu\n",
1977                 attr_fid->fid, *attr_size);
1978         return attr_fid;
1979 clunk_fid:
1980         p9_client_clunk(attr_fid);
1981         attr_fid = NULL;
1982 error:
1983         if (attr_fid && (attr_fid != file_fid))
1984                 p9_fid_destroy(attr_fid);
1985
1986         return ERR_PTR(err);
1987 }
1988 EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
1989
1990 int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
1991                         u64 attr_size, int flags)
1992 {
1993         int err;
1994         struct p9_req_t *req;
1995         struct p9_client *clnt;
1996
1997         P9_DPRINTK(P9_DEBUG_9P,
1998                 ">>> TXATTRCREATE fid %d name  %s size %lld flag %d\n",
1999                 fid->fid, name, (long long)attr_size, flags);
2000         err = 0;
2001         clnt = fid->clnt;
2002         req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
2003                         fid->fid, name, attr_size, flags);
2004         if (IS_ERR(req)) {
2005                 err = PTR_ERR(req);
2006                 goto error;
2007         }
2008         P9_DPRINTK(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);
2009         p9_free_req(clnt, req);
2010 error:
2011         return err;
2012 }
2013 EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
2014
2015 int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
2016 {
2017         int err, rsize, non_zc = 0;
2018         struct p9_client *clnt;
2019         struct p9_req_t *req;
2020         char *dataptr;
2021
2022         P9_DPRINTK(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
2023                                 fid->fid, (long long unsigned) offset, count);
2024
2025         err = 0;
2026         clnt = fid->clnt;
2027
2028         rsize = fid->iounit;
2029         if (!rsize || rsize > clnt->msize-P9_READDIRHDRSZ)
2030                 rsize = clnt->msize - P9_READDIRHDRSZ;
2031
2032         if (count < rsize)
2033                 rsize = count;
2034
2035         /* Don't bother zerocopy for small IO (< 1024) */
2036         if (clnt->trans_mod->zc_request && rsize > 1024) {
2037                 /*
2038                  * response header len is 11
2039                  * PDU Header(7) + IO Size (4)
2040                  */
2041                 req = p9_client_zc_rpc(clnt, P9_TREADDIR, data, NULL, rsize, 0,
2042                                        11, 1, "dqd", fid->fid, offset, rsize);
2043         } else {
2044                 non_zc = 1;
2045                 req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid,
2046                                     offset, rsize);
2047         }
2048         if (IS_ERR(req)) {
2049                 err = PTR_ERR(req);
2050                 goto error;
2051         }
2052
2053         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
2054         if (err) {
2055                 trace_9p_protocol_dump(clnt, req->rc);
2056                 goto free_and_error;
2057         }
2058
2059         P9_DPRINTK(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);
2060
2061         if (non_zc)
2062                 memmove(data, dataptr, count);
2063
2064         p9_free_req(clnt, req);
2065         return count;
2066
2067 free_and_error:
2068         p9_free_req(clnt, req);
2069 error:
2070         return err;
2071 }
2072 EXPORT_SYMBOL(p9_client_readdir);
2073
2074 int p9_client_mknod_dotl(struct p9_fid *fid, char *name, int mode,
2075                         dev_t rdev, gid_t gid, struct p9_qid *qid)
2076 {
2077         int err;
2078         struct p9_client *clnt;
2079         struct p9_req_t *req;
2080
2081         err = 0;
2082         clnt = fid->clnt;
2083         P9_DPRINTK(P9_DEBUG_9P, ">>> TMKNOD fid %d name %s mode %d major %d "
2084                 "minor %d\n", fid->fid, name, mode, MAJOR(rdev), MINOR(rdev));
2085         req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddd", fid->fid, name, mode,
2086                 MAJOR(rdev), MINOR(rdev), gid);
2087         if (IS_ERR(req))
2088                 return PTR_ERR(req);
2089
2090         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2091         if (err) {
2092                 trace_9p_protocol_dump(clnt, req->rc);
2093                 goto error;
2094         }
2095         P9_DPRINTK(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n", qid->type,
2096                                 (unsigned long long)qid->path, qid->version);
2097
2098 error:
2099         p9_free_req(clnt, req);
2100         return err;
2101
2102 }
2103 EXPORT_SYMBOL(p9_client_mknod_dotl);
2104
2105 int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode,
2106                                 gid_t gid, struct p9_qid *qid)
2107 {
2108         int err;
2109         struct p9_client *clnt;
2110         struct p9_req_t *req;
2111
2112         err = 0;
2113         clnt = fid->clnt;
2114         P9_DPRINTK(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
2115                  fid->fid, name, mode, gid);
2116         req = p9_client_rpc(clnt, P9_TMKDIR, "dsdd", fid->fid, name, mode,
2117                 gid);
2118         if (IS_ERR(req))
2119                 return PTR_ERR(req);
2120
2121         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2122         if (err) {
2123                 trace_9p_protocol_dump(clnt, req->rc);
2124                 goto error;
2125         }
2126         P9_DPRINTK(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type,
2127                                 (unsigned long long)qid->path, qid->version);
2128
2129 error:
2130         p9_free_req(clnt, req);
2131         return err;
2132
2133 }
2134 EXPORT_SYMBOL(p9_client_mkdir_dotl);
2135
2136 int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status)
2137 {
2138         int err;
2139         struct p9_client *clnt;
2140         struct p9_req_t *req;
2141
2142         err = 0;
2143         clnt = fid->clnt;
2144         P9_DPRINTK(P9_DEBUG_9P, ">>> TLOCK fid %d type %i flags %d "
2145                         "start %lld length %lld proc_id %d client_id %s\n",
2146                         fid->fid, flock->type, flock->flags, flock->start,
2147                         flock->length, flock->proc_id, flock->client_id);
2148
2149         req = p9_client_rpc(clnt, P9_TLOCK, "dbdqqds", fid->fid, flock->type,
2150                                 flock->flags, flock->start, flock->length,
2151                                         flock->proc_id, flock->client_id);
2152
2153         if (IS_ERR(req))
2154                 return PTR_ERR(req);
2155
2156         err = p9pdu_readf(req->rc, clnt->proto_version, "b", status);
2157         if (err) {
2158                 trace_9p_protocol_dump(clnt, req->rc);
2159                 goto error;
2160         }
2161         P9_DPRINTK(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status);
2162 error:
2163         p9_free_req(clnt, req);
2164         return err;
2165
2166 }
2167 EXPORT_SYMBOL(p9_client_lock_dotl);
2168
2169 int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock)
2170 {
2171         int err;
2172         struct p9_client *clnt;
2173         struct p9_req_t *req;
2174
2175         err = 0;
2176         clnt = fid->clnt;
2177         P9_DPRINTK(P9_DEBUG_9P, ">>> TGETLOCK fid %d, type %i start %lld "
2178                 "length %lld proc_id %d client_id %s\n", fid->fid, glock->type,
2179                 glock->start, glock->length, glock->proc_id, glock->client_id);
2180
2181         req = p9_client_rpc(clnt, P9_TGETLOCK, "dbqqds", fid->fid,  glock->type,
2182                 glock->start, glock->length, glock->proc_id, glock->client_id);
2183
2184         if (IS_ERR(req))
2185                 return PTR_ERR(req);
2186
2187         err = p9pdu_readf(req->rc, clnt->proto_version, "bqqds", &glock->type,
2188                         &glock->start, &glock->length, &glock->proc_id,
2189                         &glock->client_id);
2190         if (err) {
2191                 trace_9p_protocol_dump(clnt, req->rc);
2192                 goto error;
2193         }
2194         P9_DPRINTK(P9_DEBUG_9P, "<<< RGETLOCK type %i start %lld length %lld "
2195                 "proc_id %d client_id %s\n", glock->type, glock->start,
2196                 glock->length, glock->proc_id, glock->client_id);
2197 error:
2198         p9_free_req(clnt, req);
2199         return err;
2200 }
2201 EXPORT_SYMBOL(p9_client_getlock_dotl);
2202
2203 int p9_client_readlink(struct p9_fid *fid, char **target)
2204 {
2205         int err;
2206         struct p9_client *clnt;
2207         struct p9_req_t *req;
2208
2209         err = 0;
2210         clnt = fid->clnt;
2211         P9_DPRINTK(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid);
2212
2213         req = p9_client_rpc(clnt, P9_TREADLINK, "d", fid->fid);
2214         if (IS_ERR(req))
2215                 return PTR_ERR(req);
2216
2217         err = p9pdu_readf(req->rc, clnt->proto_version, "s", target);
2218         if (err) {
2219                 trace_9p_protocol_dump(clnt, req->rc);
2220                 goto error;
2221         }
2222         P9_DPRINTK(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target);
2223 error:
2224         p9_free_req(clnt, req);
2225         return err;
2226 }
2227 EXPORT_SYMBOL(p9_client_readlink);