iio: inv-mpu: Specify the expected format/precision for write channels
[linux/fpc-iii.git] / net / 9p / client.c
blob6f4c4c88db84ecb084ca5553113d9ad2963e4985
1 /*
2 * net/9p/clnt.c
4 * 9P Client
6 * Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
7 * Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
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.
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.
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
26 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
28 #include <linux/module.h>
29 #include <linux/errno.h>
30 #include <linux/fs.h>
31 #include <linux/poll.h>
32 #include <linux/idr.h>
33 #include <linux/mutex.h>
34 #include <linux/slab.h>
35 #include <linux/sched.h>
36 #include <linux/uaccess.h>
37 #include <linux/uio.h>
38 #include <net/9p/9p.h>
39 #include <linux/parser.h>
40 #include <net/9p/client.h>
41 #include <net/9p/transport.h>
42 #include "protocol.h"
44 #define CREATE_TRACE_POINTS
45 #include <trace/events/9p.h>
48 * Client Option Parsing (code inspired by NFS code)
49 * - a little lazy - parse all client options
52 enum {
53 Opt_msize,
54 Opt_trans,
55 Opt_legacy,
56 Opt_version,
57 Opt_err,
60 static const match_table_t tokens = {
61 {Opt_msize, "msize=%u"},
62 {Opt_legacy, "noextend"},
63 {Opt_trans, "trans=%s"},
64 {Opt_version, "version=%s"},
65 {Opt_err, NULL},
68 inline int p9_is_proto_dotl(struct p9_client *clnt)
70 return clnt->proto_version == p9_proto_2000L;
72 EXPORT_SYMBOL(p9_is_proto_dotl);
74 inline int p9_is_proto_dotu(struct p9_client *clnt)
76 return clnt->proto_version == p9_proto_2000u;
78 EXPORT_SYMBOL(p9_is_proto_dotu);
81 * Some error codes are taken directly from the server replies,
82 * make sure they are valid.
84 static int safe_errno(int err)
86 if ((err > 0) || (err < -MAX_ERRNO)) {
87 p9_debug(P9_DEBUG_ERROR, "Invalid error code %d\n", err);
88 return -EPROTO;
90 return err;
94 /* Interpret mount option for protocol version */
95 static int get_protocol_version(char *s)
97 int version = -EINVAL;
99 if (!strcmp(s, "9p2000")) {
100 version = p9_proto_legacy;
101 p9_debug(P9_DEBUG_9P, "Protocol version: Legacy\n");
102 } else if (!strcmp(s, "9p2000.u")) {
103 version = p9_proto_2000u;
104 p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.u\n");
105 } else if (!strcmp(s, "9p2000.L")) {
106 version = p9_proto_2000L;
107 p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.L\n");
108 } else
109 pr_info("Unknown protocol version %s\n", s);
111 return version;
115 * parse_options - parse mount options into client structure
116 * @opts: options string passed from mount
117 * @clnt: existing v9fs client information
119 * Return 0 upon success, -ERRNO upon failure
122 static int parse_opts(char *opts, struct p9_client *clnt)
124 char *options, *tmp_options;
125 char *p;
126 substring_t args[MAX_OPT_ARGS];
127 int option;
128 char *s;
129 int ret = 0;
131 clnt->proto_version = p9_proto_2000L;
132 clnt->msize = 8192;
134 if (!opts)
135 return 0;
137 tmp_options = kstrdup(opts, GFP_KERNEL);
138 if (!tmp_options) {
139 p9_debug(P9_DEBUG_ERROR,
140 "failed to allocate copy of option string\n");
141 return -ENOMEM;
143 options = tmp_options;
145 while ((p = strsep(&options, ",")) != NULL) {
146 int token, r;
147 if (!*p)
148 continue;
149 token = match_token(p, tokens, args);
150 switch (token) {
151 case Opt_msize:
152 r = match_int(&args[0], &option);
153 if (r < 0) {
154 p9_debug(P9_DEBUG_ERROR,
155 "integer field, but no integer?\n");
156 ret = r;
157 continue;
159 clnt->msize = option;
160 break;
161 case Opt_trans:
162 s = match_strdup(&args[0]);
163 if (!s) {
164 ret = -ENOMEM;
165 p9_debug(P9_DEBUG_ERROR,
166 "problem allocating copy of trans arg\n");
167 goto free_and_return;
169 clnt->trans_mod = v9fs_get_trans_by_name(s);
170 if (clnt->trans_mod == NULL) {
171 pr_info("Could not find request transport: %s\n",
173 ret = -EINVAL;
174 kfree(s);
175 goto free_and_return;
177 kfree(s);
178 break;
179 case Opt_legacy:
180 clnt->proto_version = p9_proto_legacy;
181 break;
182 case Opt_version:
183 s = match_strdup(&args[0]);
184 if (!s) {
185 ret = -ENOMEM;
186 p9_debug(P9_DEBUG_ERROR,
187 "problem allocating copy of version arg\n");
188 goto free_and_return;
190 ret = get_protocol_version(s);
191 if (ret == -EINVAL) {
192 kfree(s);
193 goto free_and_return;
195 kfree(s);
196 clnt->proto_version = ret;
197 break;
198 default:
199 continue;
203 free_and_return:
204 kfree(tmp_options);
205 return ret;
208 static struct p9_fcall *p9_fcall_alloc(int alloc_msize)
210 struct p9_fcall *fc;
211 fc = kmalloc(sizeof(struct p9_fcall) + alloc_msize, GFP_NOFS);
212 if (!fc)
213 return NULL;
214 fc->capacity = alloc_msize;
215 fc->sdata = (char *) fc + sizeof(struct p9_fcall);
216 return fc;
220 * p9_tag_alloc - lookup/allocate a request by tag
221 * @c: client session to lookup tag within
222 * @tag: numeric id for transaction
224 * this is a simple array lookup, but will grow the
225 * request_slots as necessary to accommodate transaction
226 * ids which did not previously have a slot.
228 * this code relies on the client spinlock to manage locks, its
229 * possible we should switch to something else, but I'd rather
230 * stick with something low-overhead for the common case.
234 static struct p9_req_t *
235 p9_tag_alloc(struct p9_client *c, u16 tag, unsigned int max_size)
237 unsigned long flags;
238 int row, col;
239 struct p9_req_t *req;
240 int alloc_msize = min(c->msize, max_size);
242 /* This looks up the original request by tag so we know which
243 * buffer to read the data into */
244 tag++;
246 if (tag >= c->max_tag) {
247 spin_lock_irqsave(&c->lock, flags);
248 /* check again since original check was outside of lock */
249 while (tag >= c->max_tag) {
250 row = (tag / P9_ROW_MAXTAG);
251 c->reqs[row] = kcalloc(P9_ROW_MAXTAG,
252 sizeof(struct p9_req_t), GFP_ATOMIC);
254 if (!c->reqs[row]) {
255 pr_err("Couldn't grow tag array\n");
256 spin_unlock_irqrestore(&c->lock, flags);
257 return ERR_PTR(-ENOMEM);
259 for (col = 0; col < P9_ROW_MAXTAG; col++) {
260 c->reqs[row][col].status = REQ_STATUS_IDLE;
261 c->reqs[row][col].tc = NULL;
263 c->max_tag += P9_ROW_MAXTAG;
265 spin_unlock_irqrestore(&c->lock, flags);
267 row = tag / P9_ROW_MAXTAG;
268 col = tag % P9_ROW_MAXTAG;
270 req = &c->reqs[row][col];
271 if (!req->wq) {
272 req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_NOFS);
273 if (!req->wq)
274 goto grow_failed;
275 init_waitqueue_head(req->wq);
278 if (!req->tc)
279 req->tc = p9_fcall_alloc(alloc_msize);
280 if (!req->rc)
281 req->rc = p9_fcall_alloc(alloc_msize);
282 if (!req->tc || !req->rc)
283 goto grow_failed;
285 p9pdu_reset(req->tc);
286 p9pdu_reset(req->rc);
288 req->tc->tag = tag-1;
289 req->status = REQ_STATUS_ALLOC;
291 return req;
293 grow_failed:
294 pr_err("Couldn't grow tag array\n");
295 kfree(req->tc);
296 kfree(req->rc);
297 kfree(req->wq);
298 req->tc = req->rc = NULL;
299 req->wq = NULL;
300 return ERR_PTR(-ENOMEM);
304 * p9_tag_lookup - lookup a request by tag
305 * @c: client session to lookup tag within
306 * @tag: numeric id for transaction
310 struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
312 int row, col;
314 /* This looks up the original request by tag so we know which
315 * buffer to read the data into */
316 tag++;
318 if(tag >= c->max_tag)
319 return NULL;
321 row = tag / P9_ROW_MAXTAG;
322 col = tag % P9_ROW_MAXTAG;
324 return &c->reqs[row][col];
326 EXPORT_SYMBOL(p9_tag_lookup);
329 * p9_tag_init - setup tags structure and contents
330 * @c: v9fs client struct
332 * This initializes the tags structure for each client instance.
336 static int p9_tag_init(struct p9_client *c)
338 int err = 0;
340 c->tagpool = p9_idpool_create();
341 if (IS_ERR(c->tagpool)) {
342 err = PTR_ERR(c->tagpool);
343 goto error;
345 err = p9_idpool_get(c->tagpool); /* reserve tag 0 */
346 if (err < 0) {
347 p9_idpool_destroy(c->tagpool);
348 goto error;
350 c->max_tag = 0;
351 error:
352 return err;
356 * p9_tag_cleanup - cleans up tags structure and reclaims resources
357 * @c: v9fs client struct
359 * This frees resources associated with the tags structure
362 static void p9_tag_cleanup(struct p9_client *c)
364 int row, col;
366 /* check to insure all requests are idle */
367 for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
368 for (col = 0; col < P9_ROW_MAXTAG; col++) {
369 if (c->reqs[row][col].status != REQ_STATUS_IDLE) {
370 p9_debug(P9_DEBUG_MUX,
371 "Attempting to cleanup non-free tag %d,%d\n",
372 row, col);
373 /* TODO: delay execution of cleanup */
374 return;
379 if (c->tagpool) {
380 p9_idpool_put(0, c->tagpool); /* free reserved tag 0 */
381 p9_idpool_destroy(c->tagpool);
384 /* free requests associated with tags */
385 for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
386 for (col = 0; col < P9_ROW_MAXTAG; col++) {
387 kfree(c->reqs[row][col].wq);
388 kfree(c->reqs[row][col].tc);
389 kfree(c->reqs[row][col].rc);
391 kfree(c->reqs[row]);
393 c->max_tag = 0;
397 * p9_free_req - free a request and clean-up as necessary
398 * c: client state
399 * r: request to release
403 static void p9_free_req(struct p9_client *c, struct p9_req_t *r)
405 int tag = r->tc->tag;
406 p9_debug(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);
408 r->status = REQ_STATUS_IDLE;
409 if (tag != P9_NOTAG && p9_idpool_check(tag, c->tagpool))
410 p9_idpool_put(tag, c->tagpool);
414 * p9_client_cb - call back from transport to client
415 * c: client state
416 * req: request received
419 void p9_client_cb(struct p9_client *c, struct p9_req_t *req, int status)
421 p9_debug(P9_DEBUG_MUX, " tag %d\n", req->tc->tag);
424 * This barrier is needed to make sure any change made to req before
425 * the other thread wakes up will indeed be seen by the waiting side.
427 smp_wmb();
428 req->status = status;
430 wake_up(req->wq);
431 p9_debug(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
433 EXPORT_SYMBOL(p9_client_cb);
436 * p9_parse_header - parse header arguments out of a packet
437 * @pdu: packet to parse
438 * @size: size of packet
439 * @type: type of request
440 * @tag: tag of packet
441 * @rewind: set if we need to rewind offset afterwards
445 p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
446 int rewind)
448 int8_t r_type;
449 int16_t r_tag;
450 int32_t r_size;
451 int offset = pdu->offset;
452 int err;
454 pdu->offset = 0;
455 if (pdu->size == 0)
456 pdu->size = 7;
458 err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
459 if (err)
460 goto rewind_and_exit;
462 pdu->size = r_size;
463 pdu->id = r_type;
464 pdu->tag = r_tag;
466 p9_debug(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n",
467 pdu->size, pdu->id, pdu->tag);
469 if (type)
470 *type = r_type;
471 if (tag)
472 *tag = r_tag;
473 if (size)
474 *size = r_size;
477 rewind_and_exit:
478 if (rewind)
479 pdu->offset = offset;
480 return err;
482 EXPORT_SYMBOL(p9_parse_header);
485 * p9_check_errors - check 9p packet for error return and process it
486 * @c: current client instance
487 * @req: request to parse and check for error conditions
489 * returns error code if one is discovered, otherwise returns 0
491 * this will have to be more complicated if we have multiple
492 * error packet types
495 static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
497 int8_t type;
498 int err;
499 int ecode;
501 err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
503 * dump the response from server
504 * This should be after check errors which poplulate pdu_fcall.
506 trace_9p_protocol_dump(c, req->rc);
507 if (err) {
508 p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
509 return err;
511 if (type != P9_RERROR && type != P9_RLERROR)
512 return 0;
514 if (!p9_is_proto_dotl(c)) {
515 char *ename;
516 err = p9pdu_readf(req->rc, c->proto_version, "s?d",
517 &ename, &ecode);
518 if (err)
519 goto out_err;
521 if (p9_is_proto_dotu(c))
522 err = -ecode;
524 if (!err || !IS_ERR_VALUE(err)) {
525 err = p9_errstr2errno(ename, strlen(ename));
527 p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
528 -ecode, ename);
530 kfree(ename);
531 } else {
532 err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
533 err = -ecode;
535 p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
538 return err;
540 out_err:
541 p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
543 return err;
547 * p9_check_zc_errors - check 9p packet for error return and process it
548 * @c: current client instance
549 * @req: request to parse and check for error conditions
550 * @in_hdrlen: Size of response protocol buffer.
552 * returns error code if one is discovered, otherwise returns 0
554 * this will have to be more complicated if we have multiple
555 * error packet types
558 static int p9_check_zc_errors(struct p9_client *c, struct p9_req_t *req,
559 struct iov_iter *uidata, int in_hdrlen)
561 int err;
562 int ecode;
563 int8_t type;
564 char *ename = NULL;
566 err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
568 * dump the response from server
569 * This should be after parse_header which poplulate pdu_fcall.
571 trace_9p_protocol_dump(c, req->rc);
572 if (err) {
573 p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
574 return err;
577 if (type != P9_RERROR && type != P9_RLERROR)
578 return 0;
580 if (!p9_is_proto_dotl(c)) {
581 /* Error is reported in string format */
582 int len;
583 /* 7 = header size for RERROR; */
584 int inline_len = in_hdrlen - 7;
586 len = req->rc->size - req->rc->offset;
587 if (len > (P9_ZC_HDR_SZ - 7)) {
588 err = -EFAULT;
589 goto out_err;
592 ename = &req->rc->sdata[req->rc->offset];
593 if (len > inline_len) {
594 /* We have error in external buffer */
595 err = copy_from_iter(ename + inline_len,
596 len - inline_len, uidata);
597 if (err != len - inline_len) {
598 err = -EFAULT;
599 goto out_err;
602 ename = NULL;
603 err = p9pdu_readf(req->rc, c->proto_version, "s?d",
604 &ename, &ecode);
605 if (err)
606 goto out_err;
608 if (p9_is_proto_dotu(c))
609 err = -ecode;
611 if (!err || !IS_ERR_VALUE(err)) {
612 err = p9_errstr2errno(ename, strlen(ename));
614 p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
615 -ecode, ename);
617 kfree(ename);
618 } else {
619 err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
620 err = -ecode;
622 p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
624 return err;
626 out_err:
627 p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
628 return err;
631 static struct p9_req_t *
632 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
635 * p9_client_flush - flush (cancel) a request
636 * @c: client state
637 * @oldreq: request to cancel
639 * This sents a flush for a particular request and links
640 * the flush request to the original request. The current
641 * code only supports a single flush request although the protocol
642 * allows for multiple flush requests to be sent for a single request.
646 static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
648 struct p9_req_t *req;
649 int16_t oldtag;
650 int err;
652 err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
653 if (err)
654 return err;
656 p9_debug(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
658 req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
659 if (IS_ERR(req))
660 return PTR_ERR(req);
663 * if we haven't received a response for oldreq,
664 * remove it from the list
666 if (oldreq->status == REQ_STATUS_SENT)
667 if (c->trans_mod->cancelled)
668 c->trans_mod->cancelled(c, oldreq);
670 p9_free_req(c, req);
671 return 0;
674 static struct p9_req_t *p9_client_prepare_req(struct p9_client *c,
675 int8_t type, int req_size,
676 const char *fmt, va_list ap)
678 int tag, err;
679 struct p9_req_t *req;
681 p9_debug(P9_DEBUG_MUX, "client %p op %d\n", c, type);
683 /* we allow for any status other than disconnected */
684 if (c->status == Disconnected)
685 return ERR_PTR(-EIO);
687 /* if status is begin_disconnected we allow only clunk request */
688 if ((c->status == BeginDisconnect) && (type != P9_TCLUNK))
689 return ERR_PTR(-EIO);
691 tag = P9_NOTAG;
692 if (type != P9_TVERSION) {
693 tag = p9_idpool_get(c->tagpool);
694 if (tag < 0)
695 return ERR_PTR(-ENOMEM);
698 req = p9_tag_alloc(c, tag, req_size);
699 if (IS_ERR(req))
700 return req;
702 /* marshall the data */
703 p9pdu_prepare(req->tc, tag, type);
704 err = p9pdu_vwritef(req->tc, c->proto_version, fmt, ap);
705 if (err)
706 goto reterr;
707 p9pdu_finalize(c, req->tc);
708 trace_9p_client_req(c, type, tag);
709 return req;
710 reterr:
711 p9_free_req(c, req);
712 return ERR_PTR(err);
716 * p9_client_rpc - issue a request and wait for a response
717 * @c: client session
718 * @type: type of request
719 * @fmt: protocol format string (see protocol.c)
721 * Returns request structure (which client must free using p9_free_req)
724 static struct p9_req_t *
725 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
727 va_list ap;
728 int sigpending, err;
729 unsigned long flags;
730 struct p9_req_t *req;
732 va_start(ap, fmt);
733 req = p9_client_prepare_req(c, type, c->msize, fmt, ap);
734 va_end(ap);
735 if (IS_ERR(req))
736 return req;
738 if (signal_pending(current)) {
739 sigpending = 1;
740 clear_thread_flag(TIF_SIGPENDING);
741 } else
742 sigpending = 0;
744 err = c->trans_mod->request(c, req);
745 if (err < 0) {
746 if (err != -ERESTARTSYS && err != -EFAULT)
747 c->status = Disconnected;
748 goto reterr;
750 again:
751 /* Wait for the response */
752 err = wait_event_interruptible(*req->wq,
753 req->status >= REQ_STATUS_RCVD);
756 * Make sure our req is coherent with regard to updates in other
757 * threads - echoes to wmb() in the callback
759 smp_rmb();
761 if ((err == -ERESTARTSYS) && (c->status == Connected)
762 && (type == P9_TFLUSH)) {
763 sigpending = 1;
764 clear_thread_flag(TIF_SIGPENDING);
765 goto again;
768 if (req->status == REQ_STATUS_ERROR) {
769 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
770 err = req->t_err;
772 if ((err == -ERESTARTSYS) && (c->status == Connected)) {
773 p9_debug(P9_DEBUG_MUX, "flushing\n");
774 sigpending = 1;
775 clear_thread_flag(TIF_SIGPENDING);
777 if (c->trans_mod->cancel(c, req))
778 p9_client_flush(c, req);
780 /* if we received the response anyway, don't signal error */
781 if (req->status == REQ_STATUS_RCVD)
782 err = 0;
784 if (sigpending) {
785 spin_lock_irqsave(&current->sighand->siglock, flags);
786 recalc_sigpending();
787 spin_unlock_irqrestore(&current->sighand->siglock, flags);
789 if (err < 0)
790 goto reterr;
792 err = p9_check_errors(c, req);
793 trace_9p_client_res(c, type, req->rc->tag, err);
794 if (!err)
795 return req;
796 reterr:
797 p9_free_req(c, req);
798 return ERR_PTR(safe_errno(err));
802 * p9_client_zc_rpc - issue a request and wait for a response
803 * @c: client session
804 * @type: type of request
805 * @uidata: destination for zero copy read
806 * @uodata: source for zero copy write
807 * @inlen: read buffer size
808 * @olen: write buffer size
809 * @hdrlen: reader header size, This is the size of response protocol data
810 * @fmt: protocol format string (see protocol.c)
812 * Returns request structure (which client must free using p9_free_req)
814 static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type,
815 struct iov_iter *uidata,
816 struct iov_iter *uodata,
817 int inlen, int olen, int in_hdrlen,
818 const char *fmt, ...)
820 va_list ap;
821 int sigpending, err;
822 unsigned long flags;
823 struct p9_req_t *req;
825 va_start(ap, fmt);
827 * We allocate a inline protocol data of only 4k bytes.
828 * The actual content is passed in zero-copy fashion.
830 req = p9_client_prepare_req(c, type, P9_ZC_HDR_SZ, fmt, ap);
831 va_end(ap);
832 if (IS_ERR(req))
833 return req;
835 if (signal_pending(current)) {
836 sigpending = 1;
837 clear_thread_flag(TIF_SIGPENDING);
838 } else
839 sigpending = 0;
841 err = c->trans_mod->zc_request(c, req, uidata, uodata,
842 inlen, olen, in_hdrlen);
843 if (err < 0) {
844 if (err == -EIO)
845 c->status = Disconnected;
846 goto reterr;
848 if (req->status == REQ_STATUS_ERROR) {
849 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
850 err = req->t_err;
852 if ((err == -ERESTARTSYS) && (c->status == Connected)) {
853 p9_debug(P9_DEBUG_MUX, "flushing\n");
854 sigpending = 1;
855 clear_thread_flag(TIF_SIGPENDING);
857 if (c->trans_mod->cancel(c, req))
858 p9_client_flush(c, req);
860 /* if we received the response anyway, don't signal error */
861 if (req->status == REQ_STATUS_RCVD)
862 err = 0;
864 if (sigpending) {
865 spin_lock_irqsave(&current->sighand->siglock, flags);
866 recalc_sigpending();
867 spin_unlock_irqrestore(&current->sighand->siglock, flags);
869 if (err < 0)
870 goto reterr;
872 err = p9_check_zc_errors(c, req, uidata, in_hdrlen);
873 trace_9p_client_res(c, type, req->rc->tag, err);
874 if (!err)
875 return req;
876 reterr:
877 p9_free_req(c, req);
878 return ERR_PTR(safe_errno(err));
881 static struct p9_fid *p9_fid_create(struct p9_client *clnt)
883 int ret;
884 struct p9_fid *fid;
885 unsigned long flags;
887 p9_debug(P9_DEBUG_FID, "clnt %p\n", clnt);
888 fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
889 if (!fid)
890 return ERR_PTR(-ENOMEM);
892 ret = p9_idpool_get(clnt->fidpool);
893 if (ret < 0) {
894 ret = -ENOSPC;
895 goto error;
897 fid->fid = ret;
899 memset(&fid->qid, 0, sizeof(struct p9_qid));
900 fid->mode = -1;
901 fid->uid = current_fsuid();
902 fid->clnt = clnt;
903 fid->rdir = NULL;
904 spin_lock_irqsave(&clnt->lock, flags);
905 list_add(&fid->flist, &clnt->fidlist);
906 spin_unlock_irqrestore(&clnt->lock, flags);
908 return fid;
910 error:
911 kfree(fid);
912 return ERR_PTR(ret);
915 static void p9_fid_destroy(struct p9_fid *fid)
917 struct p9_client *clnt;
918 unsigned long flags;
920 p9_debug(P9_DEBUG_FID, "fid %d\n", fid->fid);
921 clnt = fid->clnt;
922 p9_idpool_put(fid->fid, clnt->fidpool);
923 spin_lock_irqsave(&clnt->lock, flags);
924 list_del(&fid->flist);
925 spin_unlock_irqrestore(&clnt->lock, flags);
926 kfree(fid->rdir);
927 kfree(fid);
930 static int p9_client_version(struct p9_client *c)
932 int err = 0;
933 struct p9_req_t *req;
934 char *version;
935 int msize;
937 p9_debug(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
938 c->msize, c->proto_version);
940 switch (c->proto_version) {
941 case p9_proto_2000L:
942 req = p9_client_rpc(c, P9_TVERSION, "ds",
943 c->msize, "9P2000.L");
944 break;
945 case p9_proto_2000u:
946 req = p9_client_rpc(c, P9_TVERSION, "ds",
947 c->msize, "9P2000.u");
948 break;
949 case p9_proto_legacy:
950 req = p9_client_rpc(c, P9_TVERSION, "ds",
951 c->msize, "9P2000");
952 break;
953 default:
954 return -EINVAL;
957 if (IS_ERR(req))
958 return PTR_ERR(req);
960 err = p9pdu_readf(req->rc, c->proto_version, "ds", &msize, &version);
961 if (err) {
962 p9_debug(P9_DEBUG_9P, "version error %d\n", err);
963 trace_9p_protocol_dump(c, req->rc);
964 goto error;
967 p9_debug(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
968 if (!strncmp(version, "9P2000.L", 8))
969 c->proto_version = p9_proto_2000L;
970 else if (!strncmp(version, "9P2000.u", 8))
971 c->proto_version = p9_proto_2000u;
972 else if (!strncmp(version, "9P2000", 6))
973 c->proto_version = p9_proto_legacy;
974 else {
975 err = -EREMOTEIO;
976 goto error;
979 if (msize < c->msize)
980 c->msize = msize;
982 error:
983 kfree(version);
984 p9_free_req(c, req);
986 return err;
989 struct p9_client *p9_client_create(const char *dev_name, char *options)
991 int err;
992 struct p9_client *clnt;
993 char *client_id;
995 err = 0;
996 clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
997 if (!clnt)
998 return ERR_PTR(-ENOMEM);
1000 clnt->trans_mod = NULL;
1001 clnt->trans = NULL;
1003 client_id = utsname()->nodename;
1004 memcpy(clnt->name, client_id, strlen(client_id) + 1);
1006 spin_lock_init(&clnt->lock);
1007 INIT_LIST_HEAD(&clnt->fidlist);
1009 err = p9_tag_init(clnt);
1010 if (err < 0)
1011 goto free_client;
1013 err = parse_opts(options, clnt);
1014 if (err < 0)
1015 goto destroy_tagpool;
1017 if (!clnt->trans_mod)
1018 clnt->trans_mod = v9fs_get_default_trans();
1020 if (clnt->trans_mod == NULL) {
1021 err = -EPROTONOSUPPORT;
1022 p9_debug(P9_DEBUG_ERROR,
1023 "No transport defined or default transport\n");
1024 goto destroy_tagpool;
1027 clnt->fidpool = p9_idpool_create();
1028 if (IS_ERR(clnt->fidpool)) {
1029 err = PTR_ERR(clnt->fidpool);
1030 goto put_trans;
1033 p9_debug(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
1034 clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
1036 err = clnt->trans_mod->create(clnt, dev_name, options);
1037 if (err)
1038 goto destroy_fidpool;
1040 if (clnt->msize > clnt->trans_mod->maxsize)
1041 clnt->msize = clnt->trans_mod->maxsize;
1043 err = p9_client_version(clnt);
1044 if (err)
1045 goto close_trans;
1047 return clnt;
1049 close_trans:
1050 clnt->trans_mod->close(clnt);
1051 destroy_fidpool:
1052 p9_idpool_destroy(clnt->fidpool);
1053 put_trans:
1054 v9fs_put_trans(clnt->trans_mod);
1055 destroy_tagpool:
1056 p9_idpool_destroy(clnt->tagpool);
1057 free_client:
1058 kfree(clnt);
1059 return ERR_PTR(err);
1061 EXPORT_SYMBOL(p9_client_create);
1063 void p9_client_destroy(struct p9_client *clnt)
1065 struct p9_fid *fid, *fidptr;
1067 p9_debug(P9_DEBUG_MUX, "clnt %p\n", clnt);
1069 if (clnt->trans_mod)
1070 clnt->trans_mod->close(clnt);
1072 v9fs_put_trans(clnt->trans_mod);
1074 list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist) {
1075 pr_info("Found fid %d not clunked\n", fid->fid);
1076 p9_fid_destroy(fid);
1079 if (clnt->fidpool)
1080 p9_idpool_destroy(clnt->fidpool);
1082 p9_tag_cleanup(clnt);
1084 kfree(clnt);
1086 EXPORT_SYMBOL(p9_client_destroy);
1088 void p9_client_disconnect(struct p9_client *clnt)
1090 p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1091 clnt->status = Disconnected;
1093 EXPORT_SYMBOL(p9_client_disconnect);
1095 void p9_client_begin_disconnect(struct p9_client *clnt)
1097 p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1098 clnt->status = BeginDisconnect;
1100 EXPORT_SYMBOL(p9_client_begin_disconnect);
1102 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
1103 char *uname, kuid_t n_uname, char *aname)
1105 int err = 0;
1106 struct p9_req_t *req;
1107 struct p9_fid *fid;
1108 struct p9_qid qid;
1111 p9_debug(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
1112 afid ? afid->fid : -1, uname, aname);
1113 fid = p9_fid_create(clnt);
1114 if (IS_ERR(fid)) {
1115 err = PTR_ERR(fid);
1116 fid = NULL;
1117 goto error;
1119 fid->uid = n_uname;
1121 req = p9_client_rpc(clnt, P9_TATTACH, "ddss?u", fid->fid,
1122 afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
1123 if (IS_ERR(req)) {
1124 err = PTR_ERR(req);
1125 goto error;
1128 err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
1129 if (err) {
1130 trace_9p_protocol_dump(clnt, req->rc);
1131 p9_free_req(clnt, req);
1132 goto error;
1135 p9_debug(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
1136 qid.type, (unsigned long long)qid.path, qid.version);
1138 memmove(&fid->qid, &qid, sizeof(struct p9_qid));
1140 p9_free_req(clnt, req);
1141 return fid;
1143 error:
1144 if (fid)
1145 p9_fid_destroy(fid);
1146 return ERR_PTR(err);
1148 EXPORT_SYMBOL(p9_client_attach);
1150 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
1151 char **wnames, int clone)
1153 int err;
1154 struct p9_client *clnt;
1155 struct p9_fid *fid;
1156 struct p9_qid *wqids;
1157 struct p9_req_t *req;
1158 uint16_t nwqids, count;
1160 err = 0;
1161 wqids = NULL;
1162 clnt = oldfid->clnt;
1163 if (clone) {
1164 fid = p9_fid_create(clnt);
1165 if (IS_ERR(fid)) {
1166 err = PTR_ERR(fid);
1167 fid = NULL;
1168 goto error;
1171 fid->uid = oldfid->uid;
1172 } else
1173 fid = oldfid;
1176 p9_debug(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %ud wname[0] %s\n",
1177 oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
1179 req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
1180 nwname, wnames);
1181 if (IS_ERR(req)) {
1182 err = PTR_ERR(req);
1183 goto error;
1186 err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
1187 if (err) {
1188 trace_9p_protocol_dump(clnt, req->rc);
1189 p9_free_req(clnt, req);
1190 goto clunk_fid;
1192 p9_free_req(clnt, req);
1194 p9_debug(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
1196 if (nwqids != nwname) {
1197 err = -ENOENT;
1198 goto clunk_fid;
1201 for (count = 0; count < nwqids; count++)
1202 p9_debug(P9_DEBUG_9P, "<<< [%d] %x.%llx.%x\n",
1203 count, wqids[count].type,
1204 (unsigned long long)wqids[count].path,
1205 wqids[count].version);
1207 if (nwname)
1208 memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
1209 else
1210 fid->qid = oldfid->qid;
1212 kfree(wqids);
1213 return fid;
1215 clunk_fid:
1216 kfree(wqids);
1217 p9_client_clunk(fid);
1218 fid = NULL;
1220 error:
1221 if (fid && (fid != oldfid))
1222 p9_fid_destroy(fid);
1224 return ERR_PTR(err);
1226 EXPORT_SYMBOL(p9_client_walk);
1228 int p9_client_open(struct p9_fid *fid, int mode)
1230 int err;
1231 struct p9_client *clnt;
1232 struct p9_req_t *req;
1233 struct p9_qid qid;
1234 int iounit;
1236 clnt = fid->clnt;
1237 p9_debug(P9_DEBUG_9P, ">>> %s fid %d mode %d\n",
1238 p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode);
1239 err = 0;
1241 if (fid->mode != -1)
1242 return -EINVAL;
1244 if (p9_is_proto_dotl(clnt))
1245 req = p9_client_rpc(clnt, P9_TLOPEN, "dd", fid->fid, mode);
1246 else
1247 req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
1248 if (IS_ERR(req)) {
1249 err = PTR_ERR(req);
1250 goto error;
1253 err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1254 if (err) {
1255 trace_9p_protocol_dump(clnt, req->rc);
1256 goto free_and_error;
1259 p9_debug(P9_DEBUG_9P, "<<< %s qid %x.%llx.%x iounit %x\n",
1260 p9_is_proto_dotl(clnt) ? "RLOPEN" : "ROPEN", qid.type,
1261 (unsigned long long)qid.path, qid.version, iounit);
1263 fid->mode = mode;
1264 fid->iounit = iounit;
1266 free_and_error:
1267 p9_free_req(clnt, req);
1268 error:
1269 return err;
1271 EXPORT_SYMBOL(p9_client_open);
1273 int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode,
1274 kgid_t gid, struct p9_qid *qid)
1276 int err = 0;
1277 struct p9_client *clnt;
1278 struct p9_req_t *req;
1279 int iounit;
1281 p9_debug(P9_DEBUG_9P,
1282 ">>> TLCREATE fid %d name %s flags %d mode %d gid %d\n",
1283 ofid->fid, name, flags, mode,
1284 from_kgid(&init_user_ns, gid));
1285 clnt = ofid->clnt;
1287 if (ofid->mode != -1)
1288 return -EINVAL;
1290 req = p9_client_rpc(clnt, P9_TLCREATE, "dsddg", ofid->fid, name, flags,
1291 mode, gid);
1292 if (IS_ERR(req)) {
1293 err = PTR_ERR(req);
1294 goto error;
1297 err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", qid, &iounit);
1298 if (err) {
1299 trace_9p_protocol_dump(clnt, req->rc);
1300 goto free_and_error;
1303 p9_debug(P9_DEBUG_9P, "<<< RLCREATE qid %x.%llx.%x iounit %x\n",
1304 qid->type,
1305 (unsigned long long)qid->path,
1306 qid->version, iounit);
1308 ofid->mode = mode;
1309 ofid->iounit = iounit;
1311 free_and_error:
1312 p9_free_req(clnt, req);
1313 error:
1314 return err;
1316 EXPORT_SYMBOL(p9_client_create_dotl);
1318 int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
1319 char *extension)
1321 int err;
1322 struct p9_client *clnt;
1323 struct p9_req_t *req;
1324 struct p9_qid qid;
1325 int iounit;
1327 p9_debug(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1328 fid->fid, name, perm, mode);
1329 err = 0;
1330 clnt = fid->clnt;
1332 if (fid->mode != -1)
1333 return -EINVAL;
1335 req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1336 mode, extension);
1337 if (IS_ERR(req)) {
1338 err = PTR_ERR(req);
1339 goto error;
1342 err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1343 if (err) {
1344 trace_9p_protocol_dump(clnt, req->rc);
1345 goto free_and_error;
1348 p9_debug(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1349 qid.type,
1350 (unsigned long long)qid.path,
1351 qid.version, iounit);
1353 fid->mode = mode;
1354 fid->iounit = iounit;
1356 free_and_error:
1357 p9_free_req(clnt, req);
1358 error:
1359 return err;
1361 EXPORT_SYMBOL(p9_client_fcreate);
1363 int p9_client_symlink(struct p9_fid *dfid, char *name, char *symtgt, kgid_t gid,
1364 struct p9_qid *qid)
1366 int err = 0;
1367 struct p9_client *clnt;
1368 struct p9_req_t *req;
1370 p9_debug(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s symtgt %s\n",
1371 dfid->fid, name, symtgt);
1372 clnt = dfid->clnt;
1374 req = p9_client_rpc(clnt, P9_TSYMLINK, "dssg", dfid->fid, name, symtgt,
1375 gid);
1376 if (IS_ERR(req)) {
1377 err = PTR_ERR(req);
1378 goto error;
1381 err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1382 if (err) {
1383 trace_9p_protocol_dump(clnt, req->rc);
1384 goto free_and_error;
1387 p9_debug(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n",
1388 qid->type, (unsigned long long)qid->path, qid->version);
1390 free_and_error:
1391 p9_free_req(clnt, req);
1392 error:
1393 return err;
1395 EXPORT_SYMBOL(p9_client_symlink);
1397 int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, char *newname)
1399 struct p9_client *clnt;
1400 struct p9_req_t *req;
1402 p9_debug(P9_DEBUG_9P, ">>> TLINK dfid %d oldfid %d newname %s\n",
1403 dfid->fid, oldfid->fid, newname);
1404 clnt = dfid->clnt;
1405 req = p9_client_rpc(clnt, P9_TLINK, "dds", dfid->fid, oldfid->fid,
1406 newname);
1407 if (IS_ERR(req))
1408 return PTR_ERR(req);
1410 p9_debug(P9_DEBUG_9P, "<<< RLINK\n");
1411 p9_free_req(clnt, req);
1412 return 0;
1414 EXPORT_SYMBOL(p9_client_link);
1416 int p9_client_fsync(struct p9_fid *fid, int datasync)
1418 int err;
1419 struct p9_client *clnt;
1420 struct p9_req_t *req;
1422 p9_debug(P9_DEBUG_9P, ">>> TFSYNC fid %d datasync:%d\n",
1423 fid->fid, datasync);
1424 err = 0;
1425 clnt = fid->clnt;
1427 req = p9_client_rpc(clnt, P9_TFSYNC, "dd", fid->fid, datasync);
1428 if (IS_ERR(req)) {
1429 err = PTR_ERR(req);
1430 goto error;
1433 p9_debug(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid);
1435 p9_free_req(clnt, req);
1437 error:
1438 return err;
1440 EXPORT_SYMBOL(p9_client_fsync);
1442 int p9_client_clunk(struct p9_fid *fid)
1444 int err;
1445 struct p9_client *clnt;
1446 struct p9_req_t *req;
1447 int retries = 0;
1449 if (!fid) {
1450 pr_warn("%s (%d): Trying to clunk with NULL fid\n",
1451 __func__, task_pid_nr(current));
1452 dump_stack();
1453 return 0;
1456 again:
1457 p9_debug(P9_DEBUG_9P, ">>> TCLUNK fid %d (try %d)\n", fid->fid,
1458 retries);
1459 err = 0;
1460 clnt = fid->clnt;
1462 req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1463 if (IS_ERR(req)) {
1464 err = PTR_ERR(req);
1465 goto error;
1468 p9_debug(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1470 p9_free_req(clnt, req);
1471 error:
1473 * Fid is not valid even after a failed clunk
1474 * If interrupted, retry once then give up and
1475 * leak fid until umount.
1477 if (err == -ERESTARTSYS) {
1478 if (retries++ == 0)
1479 goto again;
1480 } else
1481 p9_fid_destroy(fid);
1482 return err;
1484 EXPORT_SYMBOL(p9_client_clunk);
1486 int p9_client_remove(struct p9_fid *fid)
1488 int err;
1489 struct p9_client *clnt;
1490 struct p9_req_t *req;
1492 p9_debug(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1493 err = 0;
1494 clnt = fid->clnt;
1496 req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1497 if (IS_ERR(req)) {
1498 err = PTR_ERR(req);
1499 goto error;
1502 p9_debug(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1504 p9_free_req(clnt, req);
1505 error:
1506 if (err == -ERESTARTSYS)
1507 p9_client_clunk(fid);
1508 else
1509 p9_fid_destroy(fid);
1510 return err;
1512 EXPORT_SYMBOL(p9_client_remove);
1514 int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags)
1516 int err = 0;
1517 struct p9_req_t *req;
1518 struct p9_client *clnt;
1520 p9_debug(P9_DEBUG_9P, ">>> TUNLINKAT fid %d %s %d\n",
1521 dfid->fid, name, flags);
1523 clnt = dfid->clnt;
1524 req = p9_client_rpc(clnt, P9_TUNLINKAT, "dsd", dfid->fid, name, flags);
1525 if (IS_ERR(req)) {
1526 err = PTR_ERR(req);
1527 goto error;
1529 p9_debug(P9_DEBUG_9P, "<<< RUNLINKAT fid %d %s\n", dfid->fid, name);
1531 p9_free_req(clnt, req);
1532 error:
1533 return err;
1535 EXPORT_SYMBOL(p9_client_unlinkat);
1538 p9_client_read(struct p9_fid *fid, u64 offset, struct iov_iter *to, int *err)
1540 struct p9_client *clnt = fid->clnt;
1541 struct p9_req_t *req;
1542 int total = 0;
1544 p9_debug(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n",
1545 fid->fid, (unsigned long long) offset, (int)iov_iter_count(to));
1547 while (iov_iter_count(to)) {
1548 int count = iov_iter_count(to);
1549 int rsize, non_zc = 0;
1550 char *dataptr;
1552 rsize = fid->iounit;
1553 if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1554 rsize = clnt->msize - P9_IOHDRSZ;
1556 if (count < rsize)
1557 rsize = count;
1559 /* Don't bother zerocopy for small IO (< 1024) */
1560 if (clnt->trans_mod->zc_request && rsize > 1024) {
1562 * response header len is 11
1563 * PDU Header(7) + IO Size (4)
1565 req = p9_client_zc_rpc(clnt, P9_TREAD, to, NULL, rsize,
1566 0, 11, "dqd", fid->fid,
1567 offset, rsize);
1568 } else {
1569 non_zc = 1;
1570 req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset,
1571 rsize);
1573 if (IS_ERR(req)) {
1574 *err = PTR_ERR(req);
1575 break;
1578 *err = p9pdu_readf(req->rc, clnt->proto_version,
1579 "D", &count, &dataptr);
1580 if (*err) {
1581 trace_9p_protocol_dump(clnt, req->rc);
1582 p9_free_req(clnt, req);
1583 break;
1586 p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1587 if (!count) {
1588 p9_free_req(clnt, req);
1589 break;
1592 if (non_zc) {
1593 int n = copy_to_iter(dataptr, count, to);
1594 total += n;
1595 offset += n;
1596 if (n != count) {
1597 *err = -EFAULT;
1598 p9_free_req(clnt, req);
1599 break;
1601 } else {
1602 iov_iter_advance(to, count);
1603 total += count;
1604 offset += count;
1606 p9_free_req(clnt, req);
1608 return total;
1610 EXPORT_SYMBOL(p9_client_read);
1613 p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err)
1615 struct p9_client *clnt = fid->clnt;
1616 struct p9_req_t *req;
1617 int total = 0;
1619 p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %zd\n",
1620 fid->fid, (unsigned long long) offset,
1621 iov_iter_count(from));
1623 while (iov_iter_count(from)) {
1624 int count = iov_iter_count(from);
1625 int rsize = fid->iounit;
1626 if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1627 rsize = clnt->msize - P9_IOHDRSZ;
1629 if (count < rsize)
1630 rsize = count;
1632 /* Don't bother zerocopy for small IO (< 1024) */
1633 if (clnt->trans_mod->zc_request && rsize > 1024) {
1634 req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, from, 0,
1635 rsize, P9_ZC_HDR_SZ, "dqd",
1636 fid->fid, offset, rsize);
1637 } else {
1638 req = p9_client_rpc(clnt, P9_TWRITE, "dqV", fid->fid,
1639 offset, rsize, from);
1641 if (IS_ERR(req)) {
1642 *err = PTR_ERR(req);
1643 break;
1646 *err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1647 if (*err) {
1648 trace_9p_protocol_dump(clnt, req->rc);
1649 p9_free_req(clnt, req);
1652 p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1654 p9_free_req(clnt, req);
1655 iov_iter_advance(from, count);
1656 total += count;
1657 offset += count;
1659 return total;
1661 EXPORT_SYMBOL(p9_client_write);
1663 struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1665 int err;
1666 struct p9_client *clnt;
1667 struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1668 struct p9_req_t *req;
1669 u16 ignored;
1671 p9_debug(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1673 if (!ret)
1674 return ERR_PTR(-ENOMEM);
1676 err = 0;
1677 clnt = fid->clnt;
1679 req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1680 if (IS_ERR(req)) {
1681 err = PTR_ERR(req);
1682 goto error;
1685 err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1686 if (err) {
1687 trace_9p_protocol_dump(clnt, req->rc);
1688 p9_free_req(clnt, req);
1689 goto error;
1692 p9_debug(P9_DEBUG_9P,
1693 "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1694 "<<< mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1695 "<<< name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1696 "<<< uid=%d gid=%d n_muid=%d\n",
1697 ret->size, ret->type, ret->dev, ret->qid.type,
1698 (unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1699 ret->atime, ret->mtime, (unsigned long long)ret->length,
1700 ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1701 from_kuid(&init_user_ns, ret->n_uid),
1702 from_kgid(&init_user_ns, ret->n_gid),
1703 from_kuid(&init_user_ns, ret->n_muid));
1705 p9_free_req(clnt, req);
1706 return ret;
1708 error:
1709 kfree(ret);
1710 return ERR_PTR(err);
1712 EXPORT_SYMBOL(p9_client_stat);
1714 struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
1715 u64 request_mask)
1717 int err;
1718 struct p9_client *clnt;
1719 struct p9_stat_dotl *ret = kmalloc(sizeof(struct p9_stat_dotl),
1720 GFP_KERNEL);
1721 struct p9_req_t *req;
1723 p9_debug(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n",
1724 fid->fid, request_mask);
1726 if (!ret)
1727 return ERR_PTR(-ENOMEM);
1729 err = 0;
1730 clnt = fid->clnt;
1732 req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
1733 if (IS_ERR(req)) {
1734 err = PTR_ERR(req);
1735 goto error;
1738 err = p9pdu_readf(req->rc, clnt->proto_version, "A", ret);
1739 if (err) {
1740 trace_9p_protocol_dump(clnt, req->rc);
1741 p9_free_req(clnt, req);
1742 goto error;
1745 p9_debug(P9_DEBUG_9P,
1746 "<<< RGETATTR st_result_mask=%lld\n"
1747 "<<< qid=%x.%llx.%x\n"
1748 "<<< st_mode=%8.8x st_nlink=%llu\n"
1749 "<<< st_uid=%d st_gid=%d\n"
1750 "<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n"
1751 "<<< st_atime_sec=%lld st_atime_nsec=%lld\n"
1752 "<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n"
1753 "<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n"
1754 "<<< st_btime_sec=%lld st_btime_nsec=%lld\n"
1755 "<<< st_gen=%lld st_data_version=%lld",
1756 ret->st_result_mask, ret->qid.type, ret->qid.path,
1757 ret->qid.version, ret->st_mode, ret->st_nlink,
1758 from_kuid(&init_user_ns, ret->st_uid),
1759 from_kgid(&init_user_ns, ret->st_gid),
1760 ret->st_rdev, ret->st_size, ret->st_blksize,
1761 ret->st_blocks, ret->st_atime_sec, ret->st_atime_nsec,
1762 ret->st_mtime_sec, ret->st_mtime_nsec, ret->st_ctime_sec,
1763 ret->st_ctime_nsec, ret->st_btime_sec, ret->st_btime_nsec,
1764 ret->st_gen, ret->st_data_version);
1766 p9_free_req(clnt, req);
1767 return ret;
1769 error:
1770 kfree(ret);
1771 return ERR_PTR(err);
1773 EXPORT_SYMBOL(p9_client_getattr_dotl);
1775 static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1777 int ret;
1779 /* NOTE: size shouldn't include its own length */
1780 /* size[2] type[2] dev[4] qid[13] */
1781 /* mode[4] atime[4] mtime[4] length[8]*/
1782 /* name[s] uid[s] gid[s] muid[s] */
1783 ret = 2+4+13+4+4+4+8+2+2+2+2;
1785 if (wst->name)
1786 ret += strlen(wst->name);
1787 if (wst->uid)
1788 ret += strlen(wst->uid);
1789 if (wst->gid)
1790 ret += strlen(wst->gid);
1791 if (wst->muid)
1792 ret += strlen(wst->muid);
1794 if ((proto_version == p9_proto_2000u) ||
1795 (proto_version == p9_proto_2000L)) {
1796 ret += 2+4+4+4; /* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1797 if (wst->extension)
1798 ret += strlen(wst->extension);
1801 return ret;
1804 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1806 int err;
1807 struct p9_req_t *req;
1808 struct p9_client *clnt;
1810 err = 0;
1811 clnt = fid->clnt;
1812 wst->size = p9_client_statsize(wst, clnt->proto_version);
1813 p9_debug(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1814 p9_debug(P9_DEBUG_9P,
1815 " sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1816 " mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1817 " name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1818 " uid=%d gid=%d n_muid=%d\n",
1819 wst->size, wst->type, wst->dev, wst->qid.type,
1820 (unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1821 wst->atime, wst->mtime, (unsigned long long)wst->length,
1822 wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1823 from_kuid(&init_user_ns, wst->n_uid),
1824 from_kgid(&init_user_ns, wst->n_gid),
1825 from_kuid(&init_user_ns, wst->n_muid));
1827 req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1828 if (IS_ERR(req)) {
1829 err = PTR_ERR(req);
1830 goto error;
1833 p9_debug(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1835 p9_free_req(clnt, req);
1836 error:
1837 return err;
1839 EXPORT_SYMBOL(p9_client_wstat);
1841 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
1843 int err;
1844 struct p9_req_t *req;
1845 struct p9_client *clnt;
1847 err = 0;
1848 clnt = fid->clnt;
1849 p9_debug(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
1850 p9_debug(P9_DEBUG_9P,
1851 " valid=%x mode=%x uid=%d gid=%d size=%lld\n"
1852 " atime_sec=%lld atime_nsec=%lld\n"
1853 " mtime_sec=%lld mtime_nsec=%lld\n",
1854 p9attr->valid, p9attr->mode,
1855 from_kuid(&init_user_ns, p9attr->uid),
1856 from_kgid(&init_user_ns, p9attr->gid),
1857 p9attr->size, p9attr->atime_sec, p9attr->atime_nsec,
1858 p9attr->mtime_sec, p9attr->mtime_nsec);
1860 req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr);
1862 if (IS_ERR(req)) {
1863 err = PTR_ERR(req);
1864 goto error;
1866 p9_debug(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);
1867 p9_free_req(clnt, req);
1868 error:
1869 return err;
1871 EXPORT_SYMBOL(p9_client_setattr);
1873 int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
1875 int err;
1876 struct p9_req_t *req;
1877 struct p9_client *clnt;
1879 err = 0;
1880 clnt = fid->clnt;
1882 p9_debug(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
1884 req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
1885 if (IS_ERR(req)) {
1886 err = PTR_ERR(req);
1887 goto error;
1890 err = p9pdu_readf(req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
1891 &sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
1892 &sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
1893 if (err) {
1894 trace_9p_protocol_dump(clnt, req->rc);
1895 p9_free_req(clnt, req);
1896 goto error;
1899 p9_debug(P9_DEBUG_9P, "<<< RSTATFS fid %d type 0x%lx bsize %ld "
1900 "blocks %llu bfree %llu bavail %llu files %llu ffree %llu "
1901 "fsid %llu namelen %ld\n",
1902 fid->fid, (long unsigned int)sb->type, (long int)sb->bsize,
1903 sb->blocks, sb->bfree, sb->bavail, sb->files, sb->ffree,
1904 sb->fsid, (long int)sb->namelen);
1906 p9_free_req(clnt, req);
1907 error:
1908 return err;
1910 EXPORT_SYMBOL(p9_client_statfs);
1912 int p9_client_rename(struct p9_fid *fid,
1913 struct p9_fid *newdirfid, const char *name)
1915 int err;
1916 struct p9_req_t *req;
1917 struct p9_client *clnt;
1919 err = 0;
1920 clnt = fid->clnt;
1922 p9_debug(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
1923 fid->fid, newdirfid->fid, name);
1925 req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid,
1926 newdirfid->fid, name);
1927 if (IS_ERR(req)) {
1928 err = PTR_ERR(req);
1929 goto error;
1932 p9_debug(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);
1934 p9_free_req(clnt, req);
1935 error:
1936 return err;
1938 EXPORT_SYMBOL(p9_client_rename);
1940 int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
1941 struct p9_fid *newdirfid, const char *new_name)
1943 int err;
1944 struct p9_req_t *req;
1945 struct p9_client *clnt;
1947 err = 0;
1948 clnt = olddirfid->clnt;
1950 p9_debug(P9_DEBUG_9P, ">>> TRENAMEAT olddirfid %d old name %s"
1951 " newdirfid %d new name %s\n", olddirfid->fid, old_name,
1952 newdirfid->fid, new_name);
1954 req = p9_client_rpc(clnt, P9_TRENAMEAT, "dsds", olddirfid->fid,
1955 old_name, newdirfid->fid, new_name);
1956 if (IS_ERR(req)) {
1957 err = PTR_ERR(req);
1958 goto error;
1961 p9_debug(P9_DEBUG_9P, "<<< RRENAMEAT newdirfid %d new name %s\n",
1962 newdirfid->fid, new_name);
1964 p9_free_req(clnt, req);
1965 error:
1966 return err;
1968 EXPORT_SYMBOL(p9_client_renameat);
1971 * An xattrwalk without @attr_name gives the fid for the lisxattr namespace
1973 struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
1974 const char *attr_name, u64 *attr_size)
1976 int err;
1977 struct p9_req_t *req;
1978 struct p9_client *clnt;
1979 struct p9_fid *attr_fid;
1981 err = 0;
1982 clnt = file_fid->clnt;
1983 attr_fid = p9_fid_create(clnt);
1984 if (IS_ERR(attr_fid)) {
1985 err = PTR_ERR(attr_fid);
1986 attr_fid = NULL;
1987 goto error;
1989 p9_debug(P9_DEBUG_9P,
1990 ">>> TXATTRWALK file_fid %d, attr_fid %d name %s\n",
1991 file_fid->fid, attr_fid->fid, attr_name);
1993 req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds",
1994 file_fid->fid, attr_fid->fid, attr_name);
1995 if (IS_ERR(req)) {
1996 err = PTR_ERR(req);
1997 goto error;
1999 err = p9pdu_readf(req->rc, clnt->proto_version, "q", attr_size);
2000 if (err) {
2001 trace_9p_protocol_dump(clnt, req->rc);
2002 p9_free_req(clnt, req);
2003 goto clunk_fid;
2005 p9_free_req(clnt, req);
2006 p9_debug(P9_DEBUG_9P, "<<< RXATTRWALK fid %d size %llu\n",
2007 attr_fid->fid, *attr_size);
2008 return attr_fid;
2009 clunk_fid:
2010 p9_client_clunk(attr_fid);
2011 attr_fid = NULL;
2012 error:
2013 if (attr_fid && (attr_fid != file_fid))
2014 p9_fid_destroy(attr_fid);
2016 return ERR_PTR(err);
2018 EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
2020 int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
2021 u64 attr_size, int flags)
2023 int err;
2024 struct p9_req_t *req;
2025 struct p9_client *clnt;
2027 p9_debug(P9_DEBUG_9P,
2028 ">>> TXATTRCREATE fid %d name %s size %lld flag %d\n",
2029 fid->fid, name, (long long)attr_size, flags);
2030 err = 0;
2031 clnt = fid->clnt;
2032 req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
2033 fid->fid, name, attr_size, flags);
2034 if (IS_ERR(req)) {
2035 err = PTR_ERR(req);
2036 goto error;
2038 p9_debug(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);
2039 p9_free_req(clnt, req);
2040 error:
2041 return err;
2043 EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
2045 int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
2047 int err, rsize, non_zc = 0;
2048 struct p9_client *clnt;
2049 struct p9_req_t *req;
2050 char *dataptr;
2051 struct kvec kv = {.iov_base = data, .iov_len = count};
2052 struct iov_iter to;
2054 iov_iter_kvec(&to, READ | ITER_KVEC, &kv, 1, count);
2056 p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
2057 fid->fid, (unsigned long long) offset, count);
2059 err = 0;
2060 clnt = fid->clnt;
2062 rsize = fid->iounit;
2063 if (!rsize || rsize > clnt->msize-P9_READDIRHDRSZ)
2064 rsize = clnt->msize - P9_READDIRHDRSZ;
2066 if (count < rsize)
2067 rsize = count;
2069 /* Don't bother zerocopy for small IO (< 1024) */
2070 if (clnt->trans_mod->zc_request && rsize > 1024) {
2072 * response header len is 11
2073 * PDU Header(7) + IO Size (4)
2075 req = p9_client_zc_rpc(clnt, P9_TREADDIR, &to, NULL, rsize, 0,
2076 11, "dqd", fid->fid, offset, rsize);
2077 } else {
2078 non_zc = 1;
2079 req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid,
2080 offset, rsize);
2082 if (IS_ERR(req)) {
2083 err = PTR_ERR(req);
2084 goto error;
2087 err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
2088 if (err) {
2089 trace_9p_protocol_dump(clnt, req->rc);
2090 goto free_and_error;
2093 p9_debug(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);
2095 if (non_zc)
2096 memmove(data, dataptr, count);
2098 p9_free_req(clnt, req);
2099 return count;
2101 free_and_error:
2102 p9_free_req(clnt, req);
2103 error:
2104 return err;
2106 EXPORT_SYMBOL(p9_client_readdir);
2108 int p9_client_mknod_dotl(struct p9_fid *fid, char *name, int mode,
2109 dev_t rdev, kgid_t gid, struct p9_qid *qid)
2111 int err;
2112 struct p9_client *clnt;
2113 struct p9_req_t *req;
2115 err = 0;
2116 clnt = fid->clnt;
2117 p9_debug(P9_DEBUG_9P, ">>> TMKNOD fid %d name %s mode %d major %d "
2118 "minor %d\n", fid->fid, name, mode, MAJOR(rdev), MINOR(rdev));
2119 req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddg", fid->fid, name, mode,
2120 MAJOR(rdev), MINOR(rdev), gid);
2121 if (IS_ERR(req))
2122 return PTR_ERR(req);
2124 err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2125 if (err) {
2126 trace_9p_protocol_dump(clnt, req->rc);
2127 goto error;
2129 p9_debug(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n", qid->type,
2130 (unsigned long long)qid->path, qid->version);
2132 error:
2133 p9_free_req(clnt, req);
2134 return err;
2137 EXPORT_SYMBOL(p9_client_mknod_dotl);
2139 int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode,
2140 kgid_t gid, struct p9_qid *qid)
2142 int err;
2143 struct p9_client *clnt;
2144 struct p9_req_t *req;
2146 err = 0;
2147 clnt = fid->clnt;
2148 p9_debug(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
2149 fid->fid, name, mode, from_kgid(&init_user_ns, gid));
2150 req = p9_client_rpc(clnt, P9_TMKDIR, "dsdg", fid->fid, name, mode,
2151 gid);
2152 if (IS_ERR(req))
2153 return PTR_ERR(req);
2155 err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2156 if (err) {
2157 trace_9p_protocol_dump(clnt, req->rc);
2158 goto error;
2160 p9_debug(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type,
2161 (unsigned long long)qid->path, qid->version);
2163 error:
2164 p9_free_req(clnt, req);
2165 return err;
2168 EXPORT_SYMBOL(p9_client_mkdir_dotl);
2170 int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status)
2172 int err;
2173 struct p9_client *clnt;
2174 struct p9_req_t *req;
2176 err = 0;
2177 clnt = fid->clnt;
2178 p9_debug(P9_DEBUG_9P, ">>> TLOCK fid %d type %i flags %d "
2179 "start %lld length %lld proc_id %d client_id %s\n",
2180 fid->fid, flock->type, flock->flags, flock->start,
2181 flock->length, flock->proc_id, flock->client_id);
2183 req = p9_client_rpc(clnt, P9_TLOCK, "dbdqqds", fid->fid, flock->type,
2184 flock->flags, flock->start, flock->length,
2185 flock->proc_id, flock->client_id);
2187 if (IS_ERR(req))
2188 return PTR_ERR(req);
2190 err = p9pdu_readf(req->rc, clnt->proto_version, "b", status);
2191 if (err) {
2192 trace_9p_protocol_dump(clnt, req->rc);
2193 goto error;
2195 p9_debug(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status);
2196 error:
2197 p9_free_req(clnt, req);
2198 return err;
2201 EXPORT_SYMBOL(p9_client_lock_dotl);
2203 int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock)
2205 int err;
2206 struct p9_client *clnt;
2207 struct p9_req_t *req;
2209 err = 0;
2210 clnt = fid->clnt;
2211 p9_debug(P9_DEBUG_9P, ">>> TGETLOCK fid %d, type %i start %lld "
2212 "length %lld proc_id %d client_id %s\n", fid->fid, glock->type,
2213 glock->start, glock->length, glock->proc_id, glock->client_id);
2215 req = p9_client_rpc(clnt, P9_TGETLOCK, "dbqqds", fid->fid, glock->type,
2216 glock->start, glock->length, glock->proc_id, glock->client_id);
2218 if (IS_ERR(req))
2219 return PTR_ERR(req);
2221 err = p9pdu_readf(req->rc, clnt->proto_version, "bqqds", &glock->type,
2222 &glock->start, &glock->length, &glock->proc_id,
2223 &glock->client_id);
2224 if (err) {
2225 trace_9p_protocol_dump(clnt, req->rc);
2226 goto error;
2228 p9_debug(P9_DEBUG_9P, "<<< RGETLOCK type %i start %lld length %lld "
2229 "proc_id %d client_id %s\n", glock->type, glock->start,
2230 glock->length, glock->proc_id, glock->client_id);
2231 error:
2232 p9_free_req(clnt, req);
2233 return err;
2235 EXPORT_SYMBOL(p9_client_getlock_dotl);
2237 int p9_client_readlink(struct p9_fid *fid, char **target)
2239 int err;
2240 struct p9_client *clnt;
2241 struct p9_req_t *req;
2243 err = 0;
2244 clnt = fid->clnt;
2245 p9_debug(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid);
2247 req = p9_client_rpc(clnt, P9_TREADLINK, "d", fid->fid);
2248 if (IS_ERR(req))
2249 return PTR_ERR(req);
2251 err = p9pdu_readf(req->rc, clnt->proto_version, "s", target);
2252 if (err) {
2253 trace_9p_protocol_dump(clnt, req->rc);
2254 goto error;
2256 p9_debug(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target);
2257 error:
2258 p9_free_req(clnt, req);
2259 return err;
2261 EXPORT_SYMBOL(p9_client_readlink);