1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * 9P Client
4 *
5 * Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
6 * Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
7 */
8
9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10
11 #include <linux/module.h>
12 #include <linux/errno.h>
13 #include <linux/fs.h>
14 #include <linux/poll.h>
15 #include <linux/idr.h>
16 #include <linux/mutex.h>
17 #include <linux/slab.h>
18 #include <linux/sched/signal.h>
19 #include <linux/uaccess.h>
20 #include <linux/uio.h>
21 #include <linux/netfs.h>
22 #include <net/9p/9p.h>
23 #include <linux/parser.h>
24 #include <linux/seq_file.h>
25 #include <net/9p/client.h>
26 #include <net/9p/transport.h>
27 #include "protocol.h"
28
29 #define CREATE_TRACE_POINTS
30 #include <trace/events/9p.h>
31
32 /* DEFAULT MSIZE = 32 pages worth of payload + P9_HDRSZ +
33 * room for write (16 extra) or read (11 extra) operands.
34 */
35
36 #define DEFAULT_MSIZE ((128 * 1024) + P9_IOHDRSZ)
37
38 /* Client Option Parsing (code inspired by NFS code)
39 * - a little lazy - parse all client options
40 */
41
42 enum {
43 Opt_msize,
44 Opt_trans,
45 Opt_legacy,
46 Opt_version,
47 Opt_err,
48 };
49
50 static const match_table_t tokens = {
51 {Opt_msize, "msize=%u"},
52 {Opt_legacy, "noextend"},
53 {Opt_trans, "trans=%s"},
54 {Opt_version, "version=%s"},
55 {Opt_err, NULL},
56 };
57
58 inline int p9_is_proto_dotl(struct p9_client *clnt)
59 {
60 return clnt->proto_version == p9_proto_2000L;
61 }
62 EXPORT_SYMBOL(p9_is_proto_dotl);
63
64 inline int p9_is_proto_dotu(struct p9_client *clnt)
65 {
66 return clnt->proto_version == p9_proto_2000u;
67 }
68 EXPORT_SYMBOL(p9_is_proto_dotu);
69
70 int p9_show_client_options(struct seq_file *m, struct p9_client *clnt)
71 {
72 if (clnt->msize != DEFAULT_MSIZE)
73 seq_printf(m, ",msize=%u", clnt->msize);
74 seq_printf(m, ",trans=%s", clnt->trans_mod->name);
75
76 switch (clnt->proto_version) {
77 case p9_proto_legacy:
78 seq_puts(m, ",noextend");
79 break;
80 case p9_proto_2000u:
81 seq_puts(m, ",version=9p2000.u");
82 break;
83 case p9_proto_2000L:
84 /* Default */
85 break;
86 }
87
88 if (clnt->trans_mod->show_options)
89 return clnt->trans_mod->show_options(m, clnt);
90 return 0;
91 }
92 EXPORT_SYMBOL(p9_show_client_options);
93
94 /* Some error codes are taken directly from the server replies,
95 * make sure they are valid.
96 */
97 static int safe_errno(int err)
98 {
99 if (err > 0 || err < -MAX_ERRNO) {
100 p9_debug(P9_DEBUG_ERROR, "Invalid error code %d\n", err);
101 return -EPROTO;
102 }
103 return err;
104 }
105
106 /* Interpret mount option for protocol version */
107 static int get_protocol_version(char *s)
108 {
109 int version = -EINVAL;
110
111 if (!strcmp(s, "9p2000")) {
112 version = p9_proto_legacy;
113 p9_debug(P9_DEBUG_9P, "Protocol version: Legacy\n");
114 } else if (!strcmp(s, "9p2000.u")) {
115 version = p9_proto_2000u;
116 p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.u\n");
117 } else if (!strcmp(s, "9p2000.L")) {
118 version = p9_proto_2000L;
119 p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.L\n");
120 } else {
121 pr_info("Unknown protocol version %s\n", s);
122 }
123
124 return version;
125 }
126
127 /**
128 * parse_opts - parse mount options into client structure
129 * @opts: options string passed from mount
130 * @clnt: existing v9fs client information
131 *
132 * Return 0 upon success, -ERRNO upon failure
133 */
134
135 static int parse_opts(char *opts, struct p9_client *clnt)
136 {
137 char *options, *tmp_options;
138 char *p;
139 substring_t args[MAX_OPT_ARGS];
140 int option;
141 char *s;
142 int ret = 0;
143
144 clnt->proto_version = p9_proto_2000L;
145 clnt->msize = DEFAULT_MSIZE;
146
147 if (!opts)
148 return 0;
149
150 tmp_options = kstrdup(opts, GFP_KERNEL);
151 if (!tmp_options)
152 return -ENOMEM;
153 options = tmp_options;
154
155 while ((p = strsep(&options, ",")) != NULL) {
156 int token, r;
157
158 if (!*p)
159 continue;
160 token = match_token(p, tokens, args);
161 switch (token) {
162 case Opt_msize:
163 r = match_int(&args[0], &option);
164 if (r < 0) {
165 p9_debug(P9_DEBUG_ERROR,
166 "integer field, but no integer?\n");
167 ret = r;
168 continue;
169 }
170 if (option < 4096) {
171 p9_debug(P9_DEBUG_ERROR,
172 "msize should be at least 4k\n");
173 ret = -EINVAL;
174 continue;
175 }
176 clnt->msize = option;
177 break;
178 case Opt_trans:
179 s = match_strdup(&args[0]);
180 if (!s) {
181 ret = -ENOMEM;
182 p9_debug(P9_DEBUG_ERROR,
183 "problem allocating copy of trans arg\n");
184 goto free_and_return;
185 }
186
187 v9fs_put_trans(clnt->trans_mod);
188 clnt->trans_mod = v9fs_get_trans_by_name(s);
189 if (!clnt->trans_mod) {
190 pr_info("Could not find request transport: %s\n",
191 s);
192 ret = -EINVAL;
193 }
194 kfree(s);
195 break;
196 case Opt_legacy:
197 clnt->proto_version = p9_proto_legacy;
198 break;
199 case Opt_version:
200 s = match_strdup(&args[0]);
201 if (!s) {
202 ret = -ENOMEM;
203 p9_debug(P9_DEBUG_ERROR,
204 "problem allocating copy of version arg\n");
205 goto free_and_return;
206 }
207 r = get_protocol_version(s);
208 if (r < 0)
209 ret = r;
210 else
211 clnt->proto_version = r;
212 kfree(s);
213 break;
214 default:
215 continue;
216 }
217 }
218
219 free_and_return:
220 if (ret)
221 v9fs_put_trans(clnt->trans_mod);
222 kfree(tmp_options);
223 return ret;
224 }
225
226 static int p9_fcall_init(struct p9_client *c, struct p9_fcall *fc,
227 int alloc_msize)
228 {
229 if (likely(c->fcall_cache) && alloc_msize == c->msize) {
230 fc->sdata = kmem_cache_alloc(c->fcall_cache, GFP_NOFS);
231 fc->cache = c->fcall_cache;
232 } else {
233 fc->sdata = kmalloc(alloc_msize, GFP_NOFS);
234 fc->cache = NULL;
235 }
236 if (!fc->sdata)
237 return -ENOMEM;
238 fc->capacity = alloc_msize;
239 fc->id = 0;
240 fc->tag = P9_NOTAG;
241 return 0;
242 }
243
244 void p9_fcall_fini(struct p9_fcall *fc)
245 {
246 /* sdata can be NULL for interrupted requests in trans_rdma,
247 * and kmem_cache_free does not do NULL-check for us
248 */
249 if (unlikely(!fc->sdata))
250 return;
251
252 if (fc->cache)
253 kmem_cache_free(fc->cache, fc->sdata);
254 else
255 kfree(fc->sdata);
256 }
257 EXPORT_SYMBOL(p9_fcall_fini);
258
259 static struct kmem_cache *p9_req_cache;
260
261 /**
262 * p9_tag_alloc - Allocate a new request.
263 * @c: Client session.
264 * @type: Transaction type.
265 * @t_size: Buffer size for holding this request
266 * (automatic calculation by format template if 0).
267 * @r_size: Buffer size for holding server's reply on this request
268 * (automatic calculation by format template if 0).
269 * @fmt: Format template for assembling 9p request message
270 * (see p9pdu_vwritef).
271 * @ap: Variable arguments to be fed to passed format template
272 * (see p9pdu_vwritef).
273 *
274 * Context: Process context.
275 * Return: Pointer to new request.
276 */
277 static struct p9_req_t *
278 p9_tag_alloc(struct p9_client *c, int8_t type, uint t_size, uint r_size,
279 const char *fmt, va_list ap)
280 {
281 struct p9_req_t *req = kmem_cache_alloc(p9_req_cache, GFP_NOFS);
282 int alloc_tsize;
283 int alloc_rsize;
284 int tag;
285 va_list apc;
286
287 va_copy(apc, ap);
288 alloc_tsize = min_t(size_t, c->msize,
289 t_size ?: p9_msg_buf_size(c, type, fmt, apc));
290 va_end(apc);
291
292 alloc_rsize = min_t(size_t, c->msize,
293 r_size ?: p9_msg_buf_size(c, type + 1, fmt, ap));
294
295 if (!req)
296 return ERR_PTR(-ENOMEM);
297
298 if (p9_fcall_init(c, &req->tc, alloc_tsize))
299 goto free_req;
300 if (p9_fcall_init(c, &req->rc, alloc_rsize))
301 goto free;
302
303 p9pdu_reset(&req->tc);
304 p9pdu_reset(&req->rc);
305 req->t_err = 0;
306 req->status = REQ_STATUS_ALLOC;
307 /* refcount needs to be set to 0 before inserting into the idr
308 * so p9_tag_lookup does not accept a request that is not fully
309 * initialized. refcount_set to 2 below will mark request ready.
310 */
311 refcount_set(&req->refcount, 0);
312 init_waitqueue_head(&req->wq);
313 INIT_LIST_HEAD(&req->req_list);
314
315 idr_preload(GFP_NOFS);
316 spin_lock_irq(&c->lock);
317 if (type == P9_TVERSION)
318 tag = idr_alloc(&c->reqs, req, P9_NOTAG, P9_NOTAG + 1,
319 GFP_NOWAIT);
320 else
321 tag = idr_alloc(&c->reqs, req, 0, P9_NOTAG, GFP_NOWAIT);
322 req->tc.tag = tag;
323 spin_unlock_irq(&c->lock);
324 idr_preload_end();
325 if (tag < 0)
326 goto free;
327
328 /* Init ref to two because in the general case there is one ref
329 * that is put asynchronously by a writer thread, one ref
330 * temporarily given by p9_tag_lookup and put by p9_client_cb
331 * in the recv thread, and one ref put by p9_req_put in the
332 * main thread. The only exception is virtio that does not use
333 * p9_tag_lookup but does not have a writer thread either
334 * (the write happens synchronously in the request/zc_request
335 * callback), so p9_client_cb eats the second ref there
336 * as the pointer is duplicated directly by virtqueue_add_sgs()
337 */
338 refcount_set(&req->refcount, 2);
339
340 return req;
341
342 free:
343 p9_fcall_fini(&req->tc);
344 p9_fcall_fini(&req->rc);
345 free_req:
346 kmem_cache_free(p9_req_cache, req);
347 return ERR_PTR(-ENOMEM);
348 }
349
350 /**
351 * p9_tag_lookup - Look up a request by tag.
352 * @c: Client session.
353 * @tag: Transaction ID.
354 *
355 * Context: Any context.
356 * Return: A request, or %NULL if there is no request with that tag.
357 */
358 struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
359 {
360 struct p9_req_t *req;
361
362 rcu_read_lock();
363 again:
364 req = idr_find(&c->reqs, tag);
365 if (req) {
366 /* We have to be careful with the req found under rcu_read_lock
367 * Thanks to SLAB_TYPESAFE_BY_RCU we can safely try to get the
368 * ref again without corrupting other data, then check again
369 * that the tag matches once we have the ref
370 */
371 if (!p9_req_try_get(req))
372 goto again;
373 if (req->tc.tag != tag) {
374 p9_req_put(c, req);
375 goto again;
376 }
377 }
378 rcu_read_unlock();
379
380 return req;
381 }
382 EXPORT_SYMBOL(p9_tag_lookup);
383
384 /**
385 * p9_tag_remove - Remove a tag.
386 * @c: Client session.
387 * @r: Request of reference.
388 *
389 * Context: Any context.
390 */
391 static void p9_tag_remove(struct p9_client *c, struct p9_req_t *r)
392 {
393 unsigned long flags;
394 u16 tag = r->tc.tag;
395
396 p9_debug(P9_DEBUG_MUX, "freeing clnt %p req %p tag: %d\n", c, r, tag);
397 spin_lock_irqsave(&c->lock, flags);
398 idr_remove(&c->reqs, tag);
399 spin_unlock_irqrestore(&c->lock, flags);
400 }
401
402 int p9_req_put(struct p9_client *c, struct p9_req_t *r)
403 {
404 if (refcount_dec_and_test(&r->refcount)) {
405 p9_tag_remove(c, r);
406
407 p9_fcall_fini(&r->tc);
408 p9_fcall_fini(&r->rc);
409 kmem_cache_free(p9_req_cache, r);
410 return 1;
411 }
412 return 0;
413 }
414 EXPORT_SYMBOL(p9_req_put);
415
416 /**
417 * p9_tag_cleanup - cleans up tags structure and reclaims resources
418 * @c: v9fs client struct
419 *
420 * This frees resources associated with the tags structure
421 *
422 */
423 static void p9_tag_cleanup(struct p9_client *c)
424 {
425 struct p9_req_t *req;
426 int id;
427
428 rcu_read_lock();
429 idr_for_each_entry(&c->reqs, req, id) {
430 pr_info("Tag %d still in use\n", id);
431 if (p9_req_put(c, req) == 0)
432 pr_warn("Packet with tag %d has still references",
433 req->tc.tag);
434 }
435 rcu_read_unlock();
436 }
437
438 /**
439 * p9_client_cb - call back from transport to client
440 * @c: client state
441 * @req: request received
442 * @status: request status, one of REQ_STATUS_*
443 *
444 */
445 void p9_client_cb(struct p9_client *c, struct p9_req_t *req, int status)
446 {
447 p9_debug(P9_DEBUG_MUX, " tag %d\n", req->tc.tag);
448
449 /* This barrier is needed to make sure any change made to req before
450 * the status change is visible to another thread
451 */
452 smp_wmb();
453 WRITE_ONCE(req->status, status);
454
455 wake_up(&req->wq);
456 p9_debug(P9_DEBUG_MUX, "wakeup: %d\n", req->tc.tag);
457 p9_req_put(c, req);
458 }
459 EXPORT_SYMBOL(p9_client_cb);
460
461 /**
462 * p9_parse_header - parse header arguments out of a packet
463 * @pdu: packet to parse
464 * @size: size of packet
465 * @type: type of request
466 * @tag: tag of packet
467 * @rewind: set if we need to rewind offset afterwards
468 */
469
470 int
471 p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type,
472 int16_t *tag, int rewind)
473 {
474 s8 r_type;
475 s16 r_tag;
476 s32 r_size;
477 int offset = pdu->offset;
478 int err;
479
480 pdu->offset = 0;
481
482 err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
483 if (err)
484 goto rewind_and_exit;
485
486 if (type)
487 *type = r_type;
488 if (tag)
489 *tag = r_tag;
490 if (size)
491 *size = r_size;
492
493 if (pdu->size != r_size || r_size < 7) {
494 err = -EINVAL;
495 goto rewind_and_exit;
496 }
497
498 pdu->id = r_type;
499 pdu->tag = r_tag;
500
501 p9_debug(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n",
502 pdu->size, pdu->id, pdu->tag);
503
504 rewind_and_exit:
505 if (rewind)
506 pdu->offset = offset;
507 return err;
508 }
509 EXPORT_SYMBOL(p9_parse_header);
510
511 /**
512 * p9_check_errors - check 9p packet for error return and process it
513 * @c: current client instance
514 * @req: request to parse and check for error conditions
515 *
516 * returns error code if one is discovered, otherwise returns 0
517 *
518 * this will have to be more complicated if we have multiple
519 * error packet types
520 */
521
522 static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
523 {
524 s8 type;
525 int err;
526 int ecode;
527
528 err = p9_parse_header(&req->rc, NULL, &type, NULL, 0);
529 if (req->rc.size > req->rc.capacity && !req->rc.zc) {
530 pr_err("requested packet size too big: %d does not fit %zu (type=%d)\n",
531 req->rc.size, req->rc.capacity, req->rc.id);
532 return -EIO;
533 }
534 /* dump the response from server
535 * This should be after check errors which poplulate pdu_fcall.
536 */
537 trace_9p_protocol_dump(c, &req->rc);
538 if (err) {
539 p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
540 return err;
541 }
542 if (type != P9_RERROR && type != P9_RLERROR)
543 return 0;
544
545 if (!p9_is_proto_dotl(c)) {
546 char *ename = NULL;
547
548 err = p9pdu_readf(&req->rc, c->proto_version, "s?d",
549 &ename, &ecode);
550 if (err) {
551 kfree(ename);
552 goto out_err;
553 }
554
555 if (p9_is_proto_dotu(c) && ecode < 512)
556 err = -ecode;
557
558 if (!err) {
559 err = p9_errstr2errno(ename, strlen(ename));
560
561 p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
562 -ecode, ename);
563 }
564 kfree(ename);
565 } else {
566 err = p9pdu_readf(&req->rc, c->proto_version, "d", &ecode);
567 if (err)
568 goto out_err;
569 err = -ecode;
570
571 p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
572 }
573
574 return err;
575
576 out_err:
577 p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
578
579 return err;
580 }
581
582 static struct p9_req_t *
583 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
584
585 /**
586 * p9_client_flush - flush (cancel) a request
587 * @c: client state
588 * @oldreq: request to cancel
589 *
590 * This sents a flush for a particular request and links
591 * the flush request to the original request. The current
592 * code only supports a single flush request although the protocol
593 * allows for multiple flush requests to be sent for a single request.
594 *
595 */
596
597 static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
598 {
599 struct p9_req_t *req;
600 s16 oldtag;
601 int err;
602
603 err = p9_parse_header(&oldreq->tc, NULL, NULL, &oldtag, 1);
604 if (err)
605 return err;
606
607 p9_debug(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
608
609 req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
610 if (IS_ERR(req))
611 return PTR_ERR(req);
612
613 /* if we haven't received a response for oldreq,
614 * remove it from the list
615 */
616 if (READ_ONCE(oldreq->status) == REQ_STATUS_SENT) {
617 if (c->trans_mod->cancelled)
618 c->trans_mod->cancelled(c, oldreq);
619 }
620
621 p9_req_put(c, req);
622 return 0;
623 }
624
625 static struct p9_req_t *p9_client_prepare_req(struct p9_client *c,
626 int8_t type, uint t_size, uint r_size,
627 const char *fmt, va_list ap)
628 {
629 int err;
630 struct p9_req_t *req;
631 va_list apc;
632
633 p9_debug(P9_DEBUG_MUX, "client %p op %d\n", c, type);
634
635 /* we allow for any status other than disconnected */
636 if (c->status == Disconnected)
637 return ERR_PTR(-EIO);
638
639 /* if status is begin_disconnected we allow only clunk request */
640 if (c->status == BeginDisconnect && type != P9_TCLUNK)
641 return ERR_PTR(-EIO);
642
643 va_copy(apc, ap);
644 req = p9_tag_alloc(c, type, t_size, r_size, fmt, apc);
645 va_end(apc);
646 if (IS_ERR(req))
647 return req;
648
649 /* marshall the data */
650 p9pdu_prepare(&req->tc, req->tc.tag, type);
651 err = p9pdu_vwritef(&req->tc, c->proto_version, fmt, ap);
652 if (err)
653 goto reterr;
654 p9pdu_finalize(c, &req->tc);
655 trace_9p_client_req(c, type, req->tc.tag);
656 return req;
657 reterr:
658 p9_req_put(c, req);
659 /* We have to put also the 2nd reference as it won't be used */
660 p9_req_put(c, req);
661 return ERR_PTR(err);
662 }
663
664 /**
665 * p9_client_rpc - issue a request and wait for a response
666 * @c: client session
667 * @type: type of request
668 * @fmt: protocol format string (see protocol.c)
669 *
670 * Returns request structure (which client must free using p9_req_put)
671 */
672
673 static struct p9_req_t *
674 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
675 {
676 va_list ap;
677 int sigpending, err;
678 unsigned long flags;
679 struct p9_req_t *req;
680 /* Passing zero for tsize/rsize to p9_client_prepare_req() tells it to
681 * auto determine an appropriate (small) request/response size
682 * according to actual message data being sent. Currently RDMA
683 * transport is excluded from this response message size optimization,
684 * as it would not cope with it, due to its pooled response buffers
685 * (using an optimized request size for RDMA as well though).
686 */
687 const uint tsize = 0;
688 const uint rsize = c->trans_mod->pooled_rbuffers ? c->msize : 0;
689
690 va_start(ap, fmt);
691 req = p9_client_prepare_req(c, type, tsize, rsize, fmt, ap);
692 va_end(ap);
693 if (IS_ERR(req))
694 return req;
695
696 req->tc.zc = false;
697 req->rc.zc = false;
698
699 if (signal_pending(current)) {
700 sigpending = 1;
701 clear_thread_flag(TIF_SIGPENDING);
702 } else {
703 sigpending = 0;
704 }
705
706 err = c->trans_mod->request(c, req);
707 if (err < 0) {
708 /* write won't happen */
709 p9_req_put(c, req);
710 if (err != -ERESTARTSYS && err != -EFAULT)
711 c->status = Disconnected;
712 goto recalc_sigpending;
713 }
714 again:
715 /* Wait for the response */
716 err = wait_event_killable(req->wq,
717 READ_ONCE(req->status) >= REQ_STATUS_RCVD);
718
719 /* Make sure our req is coherent with regard to updates in other
720 * threads - echoes to wmb() in the callback
721 */
722 smp_rmb();
723
724 if (err == -ERESTARTSYS && c->status == Connected &&
725 type == P9_TFLUSH) {
726 sigpending = 1;
727 clear_thread_flag(TIF_SIGPENDING);
728 goto again;
729 }
730
731 if (READ_ONCE(req->status) == REQ_STATUS_ERROR) {
732 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
733 err = req->t_err;
734 }
735 if (err == -ERESTARTSYS && c->status == Connected) {
736 p9_debug(P9_DEBUG_MUX, "flushing\n");
737 sigpending = 1;
738 clear_thread_flag(TIF_SIGPENDING);
739
740 if (c->trans_mod->cancel(c, req))
741 p9_client_flush(c, req);
742
743 /* if we received the response anyway, don't signal error */
744 if (READ_ONCE(req->status) == REQ_STATUS_RCVD)
745 err = 0;
746 }
747 recalc_sigpending:
748 if (sigpending) {
749 spin_lock_irqsave(¤t->sighand->siglock, flags);
750 recalc_sigpending();
751 spin_unlock_irqrestore(¤t->sighand->siglock, flags);
752 }
753 if (err < 0)
754 goto reterr;
755
756 err = p9_check_errors(c, req);
757 trace_9p_client_res(c, type, req->rc.tag, err);
758 if (!err)
759 return req;
760 reterr:
761 p9_req_put(c, req);
762 return ERR_PTR(safe_errno(err));
763 }
764
765 /**
766 * p9_client_zc_rpc - issue a request and wait for a response
767 * @c: client session
768 * @type: type of request
769 * @uidata: destination for zero copy read
770 * @uodata: source for zero copy write
771 * @inlen: read buffer size
772 * @olen: write buffer size
773 * @in_hdrlen: reader header size, This is the size of response protocol data
774 * @fmt: protocol format string (see protocol.c)
775 *
776 * Returns request structure (which client must free using p9_req_put)
777 */
778 static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type,
779 struct iov_iter *uidata,
780 struct iov_iter *uodata,
781 int inlen, int olen, int in_hdrlen,
782 const char *fmt, ...)
783 {
784 va_list ap;
785 int sigpending, err;
786 unsigned long flags;
787 struct p9_req_t *req;
788
789 va_start(ap, fmt);
790 /* We allocate a inline protocol data of only 4k bytes.
791 * The actual content is passed in zero-copy fashion.
792 */
793 req = p9_client_prepare_req(c, type, P9_ZC_HDR_SZ, P9_ZC_HDR_SZ, fmt, ap);
794 va_end(ap);
795 if (IS_ERR(req))
796 return req;
797
798 req->tc.zc = true;
799 req->rc.zc = true;
800
801 if (signal_pending(current)) {
802 sigpending = 1;
803 clear_thread_flag(TIF_SIGPENDING);
804 } else {
805 sigpending = 0;
806 }
807
808 err = c->trans_mod->zc_request(c, req, uidata, uodata,
809 inlen, olen, in_hdrlen);
810 if (err < 0) {
811 if (err == -EIO)
812 c->status = Disconnected;
813 if (err != -ERESTARTSYS)
814 goto recalc_sigpending;
815 }
816 if (READ_ONCE(req->status) == REQ_STATUS_ERROR) {
817 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
818 err = req->t_err;
819 }
820 if (err == -ERESTARTSYS && c->status == Connected) {
821 p9_debug(P9_DEBUG_MUX, "flushing\n");
822 sigpending = 1;
823 clear_thread_flag(TIF_SIGPENDING);
824
825 if (c->trans_mod->cancel(c, req))
826 p9_client_flush(c, req);
827
828 /* if we received the response anyway, don't signal error */
829 if (READ_ONCE(req->status) == REQ_STATUS_RCVD)
830 err = 0;
831 }
832 recalc_sigpending:
833 if (sigpending) {
834 spin_lock_irqsave(¤t->sighand->siglock, flags);
835 recalc_sigpending();
836 spin_unlock_irqrestore(¤t->sighand->siglock, flags);
837 }
838 if (err < 0)
839 goto reterr;
840
841 err = p9_check_errors(c, req);
842 trace_9p_client_res(c, type, req->rc.tag, err);
843 if (!err)
844 return req;
845 reterr:
846 p9_req_put(c, req);
847 return ERR_PTR(safe_errno(err));
848 }
849
850 static struct p9_fid *p9_fid_create(struct p9_client *clnt)
851 {
852 int ret;
853 struct p9_fid *fid;
854
855 p9_debug(P9_DEBUG_FID, "clnt %p\n", clnt);
856 fid = kzalloc(sizeof(*fid), GFP_KERNEL);
857 if (!fid)
858 return NULL;
859
860 fid->mode = -1;
861 fid->uid = current_fsuid();
862 fid->clnt = clnt;
863 refcount_set(&fid->count, 1);
864
865 idr_preload(GFP_KERNEL);
866 spin_lock_irq(&clnt->lock);
867 ret = idr_alloc_u32(&clnt->fids, fid, &fid->fid, P9_NOFID - 1,
868 GFP_NOWAIT);
869 spin_unlock_irq(&clnt->lock);
870 idr_preload_end();
871 if (!ret) {
872 trace_9p_fid_ref(fid, P9_FID_REF_CREATE);
873 return fid;
874 }
875
876 kfree(fid);
877 return NULL;
878 }
879
880 static void p9_fid_destroy(struct p9_fid *fid)
881 {
882 struct p9_client *clnt;
883 unsigned long flags;
884
885 p9_debug(P9_DEBUG_FID, "fid %d\n", fid->fid);
886 trace_9p_fid_ref(fid, P9_FID_REF_DESTROY);
887 clnt = fid->clnt;
888 spin_lock_irqsave(&clnt->lock, flags);
889 idr_remove(&clnt->fids, fid->fid);
890 spin_unlock_irqrestore(&clnt->lock, flags);
891 kfree(fid->rdir);
892 kfree(fid);
893 }
894
895 /* We also need to export tracepoint symbols for tracepoint_enabled() */
896 EXPORT_TRACEPOINT_SYMBOL(9p_fid_ref);
897
898 void do_trace_9p_fid_get(struct p9_fid *fid)
899 {
900 trace_9p_fid_ref(fid, P9_FID_REF_GET);
901 }
902 EXPORT_SYMBOL(do_trace_9p_fid_get);
903
904 void do_trace_9p_fid_put(struct p9_fid *fid)
905 {
906 trace_9p_fid_ref(fid, P9_FID_REF_PUT);
907 }
908 EXPORT_SYMBOL(do_trace_9p_fid_put);
909
910 static int p9_client_version(struct p9_client *c)
911 {
912 int err;
913 struct p9_req_t *req;
914 char *version = NULL;
915 int msize;
916
917 p9_debug(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
918 c->msize, c->proto_version);
919
920 switch (c->proto_version) {
921 case p9_proto_2000L:
922 req = p9_client_rpc(c, P9_TVERSION, "ds",
923 c->msize, "9P2000.L");
924 break;
925 case p9_proto_2000u:
926 req = p9_client_rpc(c, P9_TVERSION, "ds",
927 c->msize, "9P2000.u");
928 break;
929 case p9_proto_legacy:
930 req = p9_client_rpc(c, P9_TVERSION, "ds",
931 c->msize, "9P2000");
932 break;
933 default:
934 return -EINVAL;
935 }
936
937 if (IS_ERR(req))
938 return PTR_ERR(req);
939
940 err = p9pdu_readf(&req->rc, c->proto_version, "ds", &msize, &version);
941 if (err) {
942 p9_debug(P9_DEBUG_9P, "version error %d\n", err);
943 trace_9p_protocol_dump(c, &req->rc);
944 goto error;
945 }
946
947 p9_debug(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
948 if (!strncmp(version, "9P2000.L", 8)) {
949 c->proto_version = p9_proto_2000L;
950 } else if (!strncmp(version, "9P2000.u", 8)) {
951 c->proto_version = p9_proto_2000u;
952 } else if (!strncmp(version, "9P2000", 6)) {
953 c->proto_version = p9_proto_legacy;
954 } else {
955 p9_debug(P9_DEBUG_ERROR,
956 "server returned an unknown version: %s\n", version);
957 err = -EREMOTEIO;
958 goto error;
959 }
960
961 if (msize < 4096) {
962 p9_debug(P9_DEBUG_ERROR,
963 "server returned a msize < 4096: %d\n", msize);
964 err = -EREMOTEIO;
965 goto error;
966 }
967 if (msize < c->msize)
968 c->msize = msize;
969
970 error:
971 kfree(version);
972 p9_req_put(c, req);
973
974 return err;
975 }
976
977 struct p9_client *p9_client_create(const char *dev_name, char *options)
978 {
979 int err;
980 struct p9_client *clnt;
981 char *client_id;
982
983 clnt = kmalloc(sizeof(*clnt), GFP_KERNEL);
984 if (!clnt)
985 return ERR_PTR(-ENOMEM);
986
987 clnt->trans_mod = NULL;
988 clnt->trans = NULL;
989 clnt->fcall_cache = NULL;
990
991 client_id = utsname()->nodename;
992 memcpy(clnt->name, client_id, strlen(client_id) + 1);
993
994 spin_lock_init(&clnt->lock);
995 idr_init(&clnt->fids);
996 idr_init(&clnt->reqs);
997
998 err = parse_opts(options, clnt);
999 if (err < 0)
1000 goto free_client;
1001
1002 if (!clnt->trans_mod)
1003 clnt->trans_mod = v9fs_get_default_trans();
1004
1005 if (!clnt->trans_mod) {
1006 err = -EPROTONOSUPPORT;
1007 p9_debug(P9_DEBUG_ERROR,
1008 "No transport defined or default transport\n");
1009 goto free_client;
1010 }
1011
1012 p9_debug(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
1013 clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
1014
1015 err = clnt->trans_mod->create(clnt, dev_name, options);
1016 if (err)
1017 goto put_trans;
1018
1019 if (clnt->msize > clnt->trans_mod->maxsize) {
1020 clnt->msize = clnt->trans_mod->maxsize;
1021 pr_info("Limiting 'msize' to %d as this is the maximum "
1022 "supported by transport %s\n",
1023 clnt->msize, clnt->trans_mod->name
1024 );
1025 }
1026
1027 if (clnt->msize < 4096) {
1028 p9_debug(P9_DEBUG_ERROR,
1029 "Please specify a msize of at least 4k\n");
1030 err = -EINVAL;
1031 goto close_trans;
1032 }
1033
1034 err = p9_client_version(clnt);
1035 if (err)
1036 goto close_trans;
1037
1038 /* P9_HDRSZ + 4 is the smallest packet header we can have that is
1039 * followed by data accessed from userspace by read
1040 */
1041 clnt->fcall_cache =
1042 kmem_cache_create_usercopy("9p-fcall-cache", clnt->msize,
1043 0, 0, P9_HDRSZ + 4,
1044 clnt->msize - (P9_HDRSZ + 4),
1045 NULL);
1046
1047 return clnt;
1048
1049 close_trans:
1050 clnt->trans_mod->close(clnt);
1051 put_trans:
1052 v9fs_put_trans(clnt->trans_mod);
1053 free_client:
1054 kfree(clnt);
1055 return ERR_PTR(err);
1056 }
1057 EXPORT_SYMBOL(p9_client_create);
1058
1059 void p9_client_destroy(struct p9_client *clnt)
1060 {
1061 struct p9_fid *fid;
1062 int id;
1063
1064 p9_debug(P9_DEBUG_MUX, "clnt %p\n", clnt);
1065
1066 if (clnt->trans_mod)
1067 clnt->trans_mod->close(clnt);
1068
1069 v9fs_put_trans(clnt->trans_mod);
1070
1071 idr_for_each_entry(&clnt->fids, fid, id) {
1072 pr_info("Found fid %d not clunked\n", fid->fid);
1073 p9_fid_destroy(fid);
1074 }
1075
1076 p9_tag_cleanup(clnt);
1077
1078 kmem_cache_destroy(clnt->fcall_cache);
1079 kfree(clnt);
1080 }
1081 EXPORT_SYMBOL(p9_client_destroy);
1082
1083 void p9_client_disconnect(struct p9_client *clnt)
1084 {
1085 p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1086 clnt->status = Disconnected;
1087 }
1088 EXPORT_SYMBOL(p9_client_disconnect);
1089
1090 void p9_client_begin_disconnect(struct p9_client *clnt)
1091 {
1092 p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1093 clnt->status = BeginDisconnect;
1094 }
1095 EXPORT_SYMBOL(p9_client_begin_disconnect);
1096
1097 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
1098 const char *uname, kuid_t n_uname,
1099 const char *aname)
1100 {
1101 int err;
1102 struct p9_req_t *req;
1103 struct p9_fid *fid;
1104 struct p9_qid qid;
1105
1106 p9_debug(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
1107 afid ? afid->fid : -1, uname, aname);
1108 fid = p9_fid_create(clnt);
1109 if (!fid) {
1110 err = -ENOMEM;
1111 goto error;
1112 }
1113 fid->uid = n_uname;
1114
1115 req = p9_client_rpc(clnt, P9_TATTACH, "ddss?u", fid->fid,
1116 afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
1117 if (IS_ERR(req)) {
1118 err = PTR_ERR(req);
1119 goto error;
1120 }
1121
1122 err = p9pdu_readf(&req->rc, clnt->proto_version, "Q", &qid);
1123 if (err) {
1124 trace_9p_protocol_dump(clnt, &req->rc);
1125 p9_req_put(clnt, req);
1126 goto error;
1127 }
1128
1129 p9_debug(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
1130 qid.type, qid.path, qid.version);
1131
1132 memmove(&fid->qid, &qid, sizeof(struct p9_qid));
1133
1134 p9_req_put(clnt, req);
1135 return fid;
1136
1137 error:
1138 if (fid)
1139 p9_fid_destroy(fid);
1140 return ERR_PTR(err);
1141 }
1142 EXPORT_SYMBOL(p9_client_attach);
1143
1144 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
1145 const unsigned char * const *wnames, int clone)
1146 {
1147 int err;
1148 struct p9_client *clnt;
1149 struct p9_fid *fid;
1150 struct p9_qid *wqids;
1151 struct p9_req_t *req;
1152 u16 nwqids, count;
1153
1154 wqids = NULL;
1155 clnt = oldfid->clnt;
1156 if (clone) {
1157 fid = p9_fid_create(clnt);
1158 if (!fid) {
1159 err = -ENOMEM;
1160 goto error;
1161 }
1162
1163 fid->uid = oldfid->uid;
1164 } else {
1165 fid = oldfid;
1166 }
1167
1168 p9_debug(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %ud wname[0] %s\n",
1169 oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
1170 req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
1171 nwname, wnames);
1172 if (IS_ERR(req)) {
1173 err = PTR_ERR(req);
1174 goto error;
1175 }
1176
1177 err = p9pdu_readf(&req->rc, clnt->proto_version, "R", &nwqids, &wqids);
1178 if (err) {
1179 trace_9p_protocol_dump(clnt, &req->rc);
1180 p9_req_put(clnt, req);
1181 goto clunk_fid;
1182 }
1183 p9_req_put(clnt, req);
1184
1185 p9_debug(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
1186
1187 if (nwqids != nwname) {
1188 err = -ENOENT;
1189 goto clunk_fid;
1190 }
1191
1192 for (count = 0; count < nwqids; count++)
1193 p9_debug(P9_DEBUG_9P, "<<< [%d] %x.%llx.%x\n",
1194 count, wqids[count].type,
1195 wqids[count].path,
1196 wqids[count].version);
1197
1198 if (nwname)
1199 memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
1200 else
1201 memmove(&fid->qid, &oldfid->qid, sizeof(struct p9_qid));
1202
1203 kfree(wqids);
1204 return fid;
1205
1206 clunk_fid:
1207 kfree(wqids);
1208 p9_fid_put(fid);
1209 fid = NULL;
1210
1211 error:
1212 if (fid && fid != oldfid)
1213 p9_fid_destroy(fid);
1214
1215 return ERR_PTR(err);
1216 }
1217 EXPORT_SYMBOL(p9_client_walk);
1218
1219 int p9_client_open(struct p9_fid *fid, int mode)
1220 {
1221 int err;
1222 struct p9_client *clnt;
1223 struct p9_req_t *req;
1224 struct p9_qid qid;
1225 int iounit;
1226
1227 clnt = fid->clnt;
1228 p9_debug(P9_DEBUG_9P, ">>> %s fid %d mode %d\n",
1229 p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode);
1230
1231 if (fid->mode != -1)
1232 return -EINVAL;
1233
1234 if (p9_is_proto_dotl(clnt))
1235 req = p9_client_rpc(clnt, P9_TLOPEN, "dd", fid->fid, mode & P9L_MODE_MASK);
1236 else
1237 req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode & P9L_MODE_MASK);
1238 if (IS_ERR(req)) {
1239 err = PTR_ERR(req);
1240 goto error;
1241 }
1242
1243 err = p9pdu_readf(&req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1244 if (err) {
1245 trace_9p_protocol_dump(clnt, &req->rc);
1246 goto free_and_error;
1247 }
1248
1249 p9_debug(P9_DEBUG_9P, "<<< %s qid %x.%llx.%x iounit %x\n",
1250 p9_is_proto_dotl(clnt) ? "RLOPEN" : "ROPEN", qid.type,
1251 qid.path, qid.version, iounit);
1252
1253 memmove(&fid->qid, &qid, sizeof(struct p9_qid));
1254 fid->mode = mode;
1255 fid->iounit = iounit;
1256
1257 free_and_error:
1258 p9_req_put(clnt, req);
1259 error:
1260 return err;
1261 }
1262 EXPORT_SYMBOL(p9_client_open);
1263
1264 int p9_client_create_dotl(struct p9_fid *ofid, const char *name, u32 flags,
1265 u32 mode, kgid_t gid, struct p9_qid *qid)
1266 {
1267 int err;
1268 struct p9_client *clnt;
1269 struct p9_req_t *req;
1270 int iounit;
1271
1272 p9_debug(P9_DEBUG_9P,
1273 ">>> TLCREATE fid %d name %s flags %d mode %d gid %d\n",
1274 ofid->fid, name, flags, mode,
1275 from_kgid(&init_user_ns, gid));
1276 clnt = ofid->clnt;
1277
1278 if (ofid->mode != -1)
1279 return -EINVAL;
1280
1281 req = p9_client_rpc(clnt, P9_TLCREATE, "dsddg", ofid->fid, name, flags,
1282 mode & P9L_MODE_MASK, gid);
1283 if (IS_ERR(req)) {
1284 err = PTR_ERR(req);
1285 goto error;
1286 }
1287
1288 err = p9pdu_readf(&req->rc, clnt->proto_version, "Qd", qid, &iounit);
1289 if (err) {
1290 trace_9p_protocol_dump(clnt, &req->rc);
1291 goto free_and_error;
1292 }
1293
1294 p9_debug(P9_DEBUG_9P, "<<< RLCREATE qid %x.%llx.%x iounit %x\n",
1295 qid->type, qid->path, qid->version, iounit);
1296
1297 memmove(&ofid->qid, qid, sizeof(struct p9_qid));
1298 ofid->mode = flags;
1299 ofid->iounit = iounit;
1300
1301 free_and_error:
1302 p9_req_put(clnt, req);
1303 error:
1304 return err;
1305 }
1306 EXPORT_SYMBOL(p9_client_create_dotl);
1307
1308 int p9_client_fcreate(struct p9_fid *fid, const char *name, u32 perm, int mode,
1309 char *extension)
1310 {
1311 int err;
1312 struct p9_client *clnt;
1313 struct p9_req_t *req;
1314 struct p9_qid qid;
1315 int iounit;
1316
1317 p9_debug(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1318 fid->fid, name, perm, mode);
1319 clnt = fid->clnt;
1320
1321 if (fid->mode != -1)
1322 return -EINVAL;
1323
1324 req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1325 mode & P9L_MODE_MASK, extension);
1326 if (IS_ERR(req)) {
1327 err = PTR_ERR(req);
1328 goto error;
1329 }
1330
1331 err = p9pdu_readf(&req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1332 if (err) {
1333 trace_9p_protocol_dump(clnt, &req->rc);
1334 goto free_and_error;
1335 }
1336
1337 p9_debug(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1338 qid.type, qid.path, qid.version, iounit);
1339
1340 memmove(&fid->qid, &qid, sizeof(struct p9_qid));
1341 fid->mode = mode;
1342 fid->iounit = iounit;
1343
1344 free_and_error:
1345 p9_req_put(clnt, req);
1346 error:
1347 return err;
1348 }
1349 EXPORT_SYMBOL(p9_client_fcreate);
1350
1351 int p9_client_symlink(struct p9_fid *dfid, const char *name,
1352 const char *symtgt, kgid_t gid, struct p9_qid *qid)
1353 {
1354 int err;
1355 struct p9_client *clnt;
1356 struct p9_req_t *req;
1357
1358 p9_debug(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s symtgt %s\n",
1359 dfid->fid, name, symtgt);
1360 clnt = dfid->clnt;
1361
1362 req = p9_client_rpc(clnt, P9_TSYMLINK, "dssg", dfid->fid, name, symtgt,
1363 gid);
1364 if (IS_ERR(req)) {
1365 err = PTR_ERR(req);
1366 goto error;
1367 }
1368
1369 err = p9pdu_readf(&req->rc, clnt->proto_version, "Q", qid);
1370 if (err) {
1371 trace_9p_protocol_dump(clnt, &req->rc);
1372 goto free_and_error;
1373 }
1374
1375 p9_debug(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n",
1376 qid->type, qid->path, qid->version);
1377
1378 free_and_error:
1379 p9_req_put(clnt, req);
1380 error:
1381 return err;
1382 }
1383 EXPORT_SYMBOL(p9_client_symlink);
1384
1385 int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, const char *newname)
1386 {
1387 struct p9_client *clnt;
1388 struct p9_req_t *req;
1389
1390 p9_debug(P9_DEBUG_9P, ">>> TLINK dfid %d oldfid %d newname %s\n",
1391 dfid->fid, oldfid->fid, newname);
1392 clnt = dfid->clnt;
1393 req = p9_client_rpc(clnt, P9_TLINK, "dds", dfid->fid, oldfid->fid,
1394 newname);
1395 if (IS_ERR(req))
1396 return PTR_ERR(req);
1397
1398 p9_debug(P9_DEBUG_9P, "<<< RLINK\n");
1399 p9_req_put(clnt, req);
1400 return 0;
1401 }
1402 EXPORT_SYMBOL(p9_client_link);
1403
1404 int p9_client_fsync(struct p9_fid *fid, int datasync)
1405 {
1406 int err = 0;
1407 struct p9_client *clnt;
1408 struct p9_req_t *req;
1409
1410 p9_debug(P9_DEBUG_9P, ">>> TFSYNC fid %d datasync:%d\n",
1411 fid->fid, datasync);
1412 clnt = fid->clnt;
1413
1414 req = p9_client_rpc(clnt, P9_TFSYNC, "dd", fid->fid, datasync);
1415 if (IS_ERR(req)) {
1416 err = PTR_ERR(req);
1417 goto error;
1418 }
1419
1420 p9_debug(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid);
1421
1422 p9_req_put(clnt, req);
1423
1424 error:
1425 return err;
1426 }
1427 EXPORT_SYMBOL(p9_client_fsync);
1428
1429 int p9_client_clunk(struct p9_fid *fid)
1430 {
1431 int err = 0;
1432 struct p9_client *clnt;
1433 struct p9_req_t *req;
1434 int retries = 0;
1435
1436 again:
1437 p9_debug(P9_DEBUG_9P, ">>> TCLUNK fid %d (try %d)\n",
1438 fid->fid, retries);
1439 clnt = fid->clnt;
1440
1441 req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1442 if (IS_ERR(req)) {
1443 err = PTR_ERR(req);
1444 goto error;
1445 }
1446
1447 p9_debug(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1448
1449 p9_req_put(clnt, req);
1450 error:
1451 /* Fid is not valid even after a failed clunk
1452 * If interrupted, retry once then give up and
1453 * leak fid until umount.
1454 */
1455 if (err == -ERESTARTSYS) {
1456 if (retries++ == 0)
1457 goto again;
1458 } else {
1459 p9_fid_destroy(fid);
1460 }
1461 return err;
1462 }
1463 EXPORT_SYMBOL(p9_client_clunk);
1464
1465 int p9_client_remove(struct p9_fid *fid)
1466 {
1467 int err = 0;
1468 struct p9_client *clnt;
1469 struct p9_req_t *req;
1470
1471 p9_debug(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1472 clnt = fid->clnt;
1473
1474 req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1475 if (IS_ERR(req)) {
1476 err = PTR_ERR(req);
1477 goto error;
1478 }
1479
1480 p9_debug(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1481
1482 p9_req_put(clnt, req);
1483 error:
1484 if (err == -ERESTARTSYS)
1485 p9_fid_put(fid);
1486 else
1487 p9_fid_destroy(fid);
1488 return err;
1489 }
1490 EXPORT_SYMBOL(p9_client_remove);
1491
1492 int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags)
1493 {
1494 int err = 0;
1495 struct p9_req_t *req;
1496 struct p9_client *clnt;
1497
1498 p9_debug(P9_DEBUG_9P, ">>> TUNLINKAT fid %d %s %d\n",
1499 dfid->fid, name, flags);
1500
1501 clnt = dfid->clnt;
1502 req = p9_client_rpc(clnt, P9_TUNLINKAT, "dsd", dfid->fid, name, flags);
1503 if (IS_ERR(req)) {
1504 err = PTR_ERR(req);
1505 goto error;
1506 }
1507 p9_debug(P9_DEBUG_9P, "<<< RUNLINKAT fid %d %s\n", dfid->fid, name);
1508
1509 p9_req_put(clnt, req);
1510 error:
1511 return err;
1512 }
1513 EXPORT_SYMBOL(p9_client_unlinkat);
1514
1515 int
1516 p9_client_read(struct p9_fid *fid, u64 offset, struct iov_iter *to, int *err)
1517 {
1518 int total = 0;
1519 *err = 0;
1520
1521 while (iov_iter_count(to)) {
1522 int count;
1523
1524 count = p9_client_read_once(fid, offset, to, err);
1525 if (!count || *err)
1526 break;
1527 offset += count;
1528 total += count;
1529 }
1530 return total;
1531 }
1532 EXPORT_SYMBOL(p9_client_read);
1533
1534 int
1535 p9_client_read_once(struct p9_fid *fid, u64 offset, struct iov_iter *to,
1536 int *err)
1537 {
1538 struct p9_client *clnt = fid->clnt;
1539 struct p9_req_t *req;
1540 int count = iov_iter_count(to);
1541 int rsize, received, non_zc = 0;
1542 char *dataptr;
1543
1544 *err = 0;
1545 p9_debug(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %zu\n",
1546 fid->fid, offset, iov_iter_count(to));
1547
1548 rsize = fid->iounit;
1549 if (!rsize || rsize > clnt->msize - P9_IOHDRSZ)
1550 rsize = clnt->msize - P9_IOHDRSZ;
1551
1552 if (count < rsize)
1553 rsize = count;
1554
1555 /* Don't bother zerocopy for small IO (< 1024) */
1556 if (clnt->trans_mod->zc_request && rsize > 1024) {
1557 /* response header len is 11
1558 * PDU Header(7) + IO Size (4)
1559 */
1560 req = p9_client_zc_rpc(clnt, P9_TREAD, to, NULL, rsize,
1561 0, 11, "dqd", fid->fid,
1562 offset, rsize);
1563 } else {
1564 non_zc = 1;
1565 req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset,
1566 rsize);
1567 }
1568 if (IS_ERR(req)) {
1569 *err = PTR_ERR(req);
1570 if (!non_zc)
1571 iov_iter_revert(to, count - iov_iter_count(to));
1572 return 0;
1573 }
1574
1575 *err = p9pdu_readf(&req->rc, clnt->proto_version,
1576 "D", &received, &dataptr);
1577 if (*err) {
1578 if (!non_zc)
1579 iov_iter_revert(to, count - iov_iter_count(to));
1580 trace_9p_protocol_dump(clnt, &req->rc);
1581 p9_req_put(clnt, req);
1582 return 0;
1583 }
1584 if (rsize < received) {
1585 pr_err("bogus RREAD count (%d > %d)\n", received, rsize);
1586 received = rsize;
1587 }
1588
1589 p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", received);
1590
1591 if (non_zc) {
1592 int n = copy_to_iter(dataptr, received, to);
1593
1594 if (n != received) {
1595 *err = -EFAULT;
1596 p9_req_put(clnt, req);
1597 return n;
1598 }
1599 } else {
1600 iov_iter_revert(to, count - received - iov_iter_count(to));
1601 }
1602 p9_req_put(clnt, req);
1603 return received;
1604 }
1605 EXPORT_SYMBOL(p9_client_read_once);
1606
1607 int
1608 p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err)
1609 {
1610 struct p9_client *clnt = fid->clnt;
1611 struct p9_req_t *req;
1612 int total = 0;
1613 *err = 0;
1614
1615 while (iov_iter_count(from)) {
1616 int count = iov_iter_count(from);
1617 int rsize = fid->iounit;
1618 int written;
1619
1620 if (!rsize || rsize > clnt->msize - P9_IOHDRSZ)
1621 rsize = clnt->msize - P9_IOHDRSZ;
1622
1623 if (count < rsize)
1624 rsize = count;
1625
1626 p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d (/%d)\n",
1627 fid->fid, offset, rsize, count);
1628
1629 /* Don't bother zerocopy for small IO (< 1024) */
1630 if (clnt->trans_mod->zc_request && rsize > 1024) {
1631 req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, from, 0,
1632 rsize, P9_ZC_HDR_SZ, "dqd",
1633 fid->fid, offset, rsize);
1634 } else {
1635 req = p9_client_rpc(clnt, P9_TWRITE, "dqV", fid->fid,
1636 offset, rsize, from);
1637 }
1638 if (IS_ERR(req)) {
1639 iov_iter_revert(from, count - iov_iter_count(from));
1640 *err = PTR_ERR(req);
1641 break;
1642 }
1643
1644 *err = p9pdu_readf(&req->rc, clnt->proto_version, "d", &written);
1645 if (*err) {
1646 iov_iter_revert(from, count - iov_iter_count(from));
1647 trace_9p_protocol_dump(clnt, &req->rc);
1648 p9_req_put(clnt, req);
1649 break;
1650 }
1651 if (rsize < written) {
1652 pr_err("bogus RWRITE count (%d > %d)\n", written, rsize);
1653 written = rsize;
1654 }
1655
1656 p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", written);
1657
1658 p9_req_put(clnt, req);
1659 iov_iter_revert(from, count - written - iov_iter_count(from));
1660 total += written;
1661 offset += written;
1662 }
1663 return total;
1664 }
1665 EXPORT_SYMBOL(p9_client_write);
1666
1667 void
1668 p9_client_write_subreq(struct netfs_io_subrequest *subreq)
1669 {
1670 struct netfs_io_request *wreq = subreq->rreq;
1671 struct p9_fid *fid = wreq->netfs_priv;
1672 struct p9_client *clnt = fid->clnt;
1673 struct p9_req_t *req;
1674 unsigned long long start = subreq->start + subreq->transferred;
1675 int written, len = subreq->len - subreq->transferred;
1676 int err;
1677
1678 p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu len %d\n",
1679 fid->fid, start, len);
1680
1681 /* Don't bother zerocopy for small IO (< 1024) */
1682 if (clnt->trans_mod->zc_request && len > 1024) {
1683 req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, &subreq->io_iter,
1684 0, wreq->len, P9_ZC_HDR_SZ, "dqd",
1685 fid->fid, start, len);
1686 } else {
1687 req = p9_client_rpc(clnt, P9_TWRITE, "dqV", fid->fid,
1688 start, len, &subreq->io_iter);
1689 }
1690 if (IS_ERR(req)) {
1691 netfs_write_subrequest_terminated(subreq, PTR_ERR(req), false);
1692 return;
1693 }
1694
1695 err = p9pdu_readf(&req->rc, clnt->proto_version, "d", &written);
1696 if (err) {
1697 trace_9p_protocol_dump(clnt, &req->rc);
1698 p9_req_put(clnt, req);
1699 netfs_write_subrequest_terminated(subreq, err, false);
1700 return;
1701 }
1702
1703 if (written > len) {
1704 pr_err("bogus RWRITE count (%d > %u)\n", written, len);
1705 written = len;
1706 }
1707
1708 p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", len);
1709
1710 p9_req_put(clnt, req);
1711 netfs_write_subrequest_terminated(subreq, written, false);
1712 }
1713 EXPORT_SYMBOL(p9_client_write_subreq);
1714
1715 struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1716 {
1717 int err;
1718 struct p9_client *clnt;
1719 struct p9_wstat *ret;
1720 struct p9_req_t *req;
1721 u16 ignored;
1722
1723 p9_debug(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1724
1725 ret = kmalloc(sizeof(*ret), GFP_KERNEL);
1726 if (!ret)
1727 return ERR_PTR(-ENOMEM);
1728
1729 clnt = fid->clnt;
1730
1731 req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1732 if (IS_ERR(req)) {
1733 err = PTR_ERR(req);
1734 goto error;
1735 }
1736
1737 err = p9pdu_readf(&req->rc, clnt->proto_version, "wS", &ignored, ret);
1738 if (err) {
1739 trace_9p_protocol_dump(clnt, &req->rc);
1740 p9_req_put(clnt, req);
1741 goto error;
1742 }
1743
1744 p9_debug(P9_DEBUG_9P,
1745 "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1746 "<<< mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1747 "<<< name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1748 "<<< uid=%d gid=%d n_muid=%d\n",
1749 ret->size, ret->type, ret->dev, ret->qid.type, ret->qid.path,
1750 ret->qid.version, ret->mode,
1751 ret->atime, ret->mtime, ret->length,
1752 ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1753 from_kuid(&init_user_ns, ret->n_uid),
1754 from_kgid(&init_user_ns, ret->n_gid),
1755 from_kuid(&init_user_ns, ret->n_muid));
1756
1757 p9_req_put(clnt, req);
1758 return ret;
1759
1760 error:
1761 kfree(ret);
1762 return ERR_PTR(err);
1763 }
1764 EXPORT_SYMBOL(p9_client_stat);
1765
1766 struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
1767 u64 request_mask)
1768 {
1769 int err;
1770 struct p9_client *clnt;
1771 struct p9_stat_dotl *ret;
1772 struct p9_req_t *req;
1773
1774 p9_debug(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n",
1775 fid->fid, request_mask);
1776
1777 ret = kmalloc(sizeof(*ret), GFP_KERNEL);
1778 if (!ret)
1779 return ERR_PTR(-ENOMEM);
1780
1781 clnt = fid->clnt;
1782
1783 req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
1784 if (IS_ERR(req)) {
1785 err = PTR_ERR(req);
1786 goto error;
1787 }
1788
1789 err = p9pdu_readf(&req->rc, clnt->proto_version, "A", ret);
1790 if (err) {
1791 trace_9p_protocol_dump(clnt, &req->rc);
1792 p9_req_put(clnt, req);
1793 goto error;
1794 }
1795
1796 p9_debug(P9_DEBUG_9P, "<<< RGETATTR st_result_mask=%lld\n"
1797 "<<< qid=%x.%llx.%x\n"
1798 "<<< st_mode=%8.8x st_nlink=%llu\n"
1799 "<<< st_uid=%d st_gid=%d\n"
1800 "<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n"
1801 "<<< st_atime_sec=%lld st_atime_nsec=%lld\n"
1802 "<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n"
1803 "<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n"
1804 "<<< st_btime_sec=%lld st_btime_nsec=%lld\n"
1805 "<<< st_gen=%lld st_data_version=%lld\n",
1806 ret->st_result_mask,
1807 ret->qid.type, ret->qid.path, ret->qid.version,
1808 ret->st_mode, ret->st_nlink,
1809 from_kuid(&init_user_ns, ret->st_uid),
1810 from_kgid(&init_user_ns, ret->st_gid),
1811 ret->st_rdev, ret->st_size, ret->st_blksize, ret->st_blocks,
1812 ret->st_atime_sec, ret->st_atime_nsec,
1813 ret->st_mtime_sec, ret->st_mtime_nsec,
1814 ret->st_ctime_sec, ret->st_ctime_nsec,
1815 ret->st_btime_sec, ret->st_btime_nsec,
1816 ret->st_gen, ret->st_data_version);
1817
1818 p9_req_put(clnt, req);
1819 return ret;
1820
1821 error:
1822 kfree(ret);
1823 return ERR_PTR(err);
1824 }
1825 EXPORT_SYMBOL(p9_client_getattr_dotl);
1826
1827 static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1828 {
1829 int ret;
1830
1831 /* NOTE: size shouldn't include its own length */
1832 /* size[2] type[2] dev[4] qid[13] */
1833 /* mode[4] atime[4] mtime[4] length[8]*/
1834 /* name[s] uid[s] gid[s] muid[s] */
1835 ret = 2 + 4 + 13 + 4 + 4 + 4 + 8 + 2 + 2 + 2 + 2;
1836
1837 if (wst->name)
1838 ret += strlen(wst->name);
1839 if (wst->uid)
1840 ret += strlen(wst->uid);
1841 if (wst->gid)
1842 ret += strlen(wst->gid);
1843 if (wst->muid)
1844 ret += strlen(wst->muid);
1845
1846 if (proto_version == p9_proto_2000u ||
1847 proto_version == p9_proto_2000L) {
1848 /* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1849 ret += 2 + 4 + 4 + 4;
1850 if (wst->extension)
1851 ret += strlen(wst->extension);
1852 }
1853
1854 return ret;
1855 }
1856
1857 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1858 {
1859 int err = 0;
1860 struct p9_req_t *req;
1861 struct p9_client *clnt;
1862
1863 clnt = fid->clnt;
1864 wst->size = p9_client_statsize(wst, clnt->proto_version);
1865 p9_debug(P9_DEBUG_9P, ">>> TWSTAT fid %d\n",
1866 fid->fid);
1867 p9_debug(P9_DEBUG_9P,
1868 " sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1869 " mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1870 " name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1871 " uid=%d gid=%d n_muid=%d\n",
1872 wst->size, wst->type, wst->dev, wst->qid.type,
1873 wst->qid.path, wst->qid.version,
1874 wst->mode, wst->atime, wst->mtime, wst->length,
1875 wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1876 from_kuid(&init_user_ns, wst->n_uid),
1877 from_kgid(&init_user_ns, wst->n_gid),
1878 from_kuid(&init_user_ns, wst->n_muid));
1879
1880 req = p9_client_rpc(clnt, P9_TWSTAT, "dwS",
1881 fid->fid, wst->size + 2, wst);
1882 if (IS_ERR(req)) {
1883 err = PTR_ERR(req);
1884 goto error;
1885 }
1886
1887 p9_debug(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1888
1889 p9_req_put(clnt, req);
1890 error:
1891 return err;
1892 }
1893 EXPORT_SYMBOL(p9_client_wstat);
1894
1895 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
1896 {
1897 int err = 0;
1898 struct p9_req_t *req;
1899 struct p9_client *clnt;
1900
1901 clnt = fid->clnt;
1902 p9_debug(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
1903 p9_debug(P9_DEBUG_9P, " valid=%x mode=%x uid=%d gid=%d size=%lld\n",
1904 p9attr->valid, p9attr->mode,
1905 from_kuid(&init_user_ns, p9attr->uid),
1906 from_kgid(&init_user_ns, p9attr->gid),
1907 p9attr->size);
1908 p9_debug(P9_DEBUG_9P, " atime_sec=%lld atime_nsec=%lld\n",
1909 p9attr->atime_sec, p9attr->atime_nsec);
1910 p9_debug(P9_DEBUG_9P, " mtime_sec=%lld mtime_nsec=%lld\n",
1911 p9attr->mtime_sec, p9attr->mtime_nsec);
1912
1913 req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr);
1914
1915 if (IS_ERR(req)) {
1916 err = PTR_ERR(req);
1917 goto error;
1918 }
1919 p9_debug(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);
1920 p9_req_put(clnt, req);
1921 error:
1922 return err;
1923 }
1924 EXPORT_SYMBOL(p9_client_setattr);
1925
1926 int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
1927 {
1928 int err;
1929 struct p9_req_t *req;
1930 struct p9_client *clnt;
1931
1932 clnt = fid->clnt;
1933
1934 p9_debug(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
1935
1936 req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
1937 if (IS_ERR(req)) {
1938 err = PTR_ERR(req);
1939 goto error;
1940 }
1941
1942 err = p9pdu_readf(&req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
1943 &sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
1944 &sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
1945 if (err) {
1946 trace_9p_protocol_dump(clnt, &req->rc);
1947 p9_req_put(clnt, req);
1948 goto error;
1949 }
1950
1951 p9_debug(P9_DEBUG_9P,
1952 "<<< RSTATFS fid %d type 0x%x bsize %u blocks %llu bfree %llu bavail %llu files %llu ffree %llu fsid %llu namelen %u\n",
1953 fid->fid, sb->type, sb->bsize, sb->blocks, sb->bfree,
1954 sb->bavail, sb->files, sb->ffree, sb->fsid, sb->namelen);
1955
1956 p9_req_put(clnt, req);
1957 error:
1958 return err;
1959 }
1960 EXPORT_SYMBOL(p9_client_statfs);
1961
1962 int p9_client_rename(struct p9_fid *fid,
1963 struct p9_fid *newdirfid, const char *name)
1964 {
1965 int err = 0;
1966 struct p9_req_t *req;
1967 struct p9_client *clnt;
1968
1969 clnt = fid->clnt;
1970
1971 p9_debug(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
1972 fid->fid, newdirfid->fid, name);
1973
1974 req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid,
1975 newdirfid->fid, name);
1976 if (IS_ERR(req)) {
1977 err = PTR_ERR(req);
1978 goto error;
1979 }
1980
1981 p9_debug(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);
1982
1983 p9_req_put(clnt, req);
1984 error:
1985 return err;
1986 }
1987 EXPORT_SYMBOL(p9_client_rename);
1988
1989 int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
1990 struct p9_fid *newdirfid, const char *new_name)
1991 {
1992 int err = 0;
1993 struct p9_req_t *req;
1994 struct p9_client *clnt;
1995
1996 clnt = olddirfid->clnt;
1997
1998 p9_debug(P9_DEBUG_9P,
1999 ">>> TRENAMEAT olddirfid %d old name %s newdirfid %d new name %s\n",
2000 olddirfid->fid, old_name, newdirfid->fid, new_name);
2001
2002 req = p9_client_rpc(clnt, P9_TRENAMEAT, "dsds", olddirfid->fid,
2003 old_name, newdirfid->fid, new_name);
2004 if (IS_ERR(req)) {
2005 err = PTR_ERR(req);
2006 goto error;
2007 }
2008
2009 p9_debug(P9_DEBUG_9P, "<<< RRENAMEAT newdirfid %d new name %s\n",
2010 newdirfid->fid, new_name);
2011
2012 p9_req_put(clnt, req);
2013 error:
2014 return err;
2015 }
2016 EXPORT_SYMBOL(p9_client_renameat);
2017
2018 /* An xattrwalk without @attr_name gives the fid for the lisxattr namespace
2019 */
2020 struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
2021 const char *attr_name, u64 *attr_size)
2022 {
2023 int err;
2024 struct p9_req_t *req;
2025 struct p9_client *clnt;
2026 struct p9_fid *attr_fid;
2027
2028 clnt = file_fid->clnt;
2029 attr_fid = p9_fid_create(clnt);
2030 if (!attr_fid) {
2031 err = -ENOMEM;
2032 goto error;
2033 }
2034 p9_debug(P9_DEBUG_9P,
2035 ">>> TXATTRWALK file_fid %d, attr_fid %d name '%s'\n",
2036 file_fid->fid, attr_fid->fid, attr_name);
2037
2038 req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds",
2039 file_fid->fid, attr_fid->fid, attr_name);
2040 if (IS_ERR(req)) {
2041 err = PTR_ERR(req);
2042 goto error;
2043 }
2044 err = p9pdu_readf(&req->rc, clnt->proto_version, "q", attr_size);
2045 if (err) {
2046 trace_9p_protocol_dump(clnt, &req->rc);
2047 p9_req_put(clnt, req);
2048 goto clunk_fid;
2049 }
2050 p9_req_put(clnt, req);
2051 p9_debug(P9_DEBUG_9P, "<<< RXATTRWALK fid %d size %llu\n",
2052 attr_fid->fid, *attr_size);
2053 return attr_fid;
2054 clunk_fid:
2055 p9_fid_put(attr_fid);
2056 attr_fid = NULL;
2057 error:
2058 if (attr_fid && attr_fid != file_fid)
2059 p9_fid_destroy(attr_fid);
2060
2061 return ERR_PTR(err);
2062 }
2063 EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
2064
2065 int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
2066 u64 attr_size, int flags)
2067 {
2068 int err = 0;
2069 struct p9_req_t *req;
2070 struct p9_client *clnt;
2071
2072 p9_debug(P9_DEBUG_9P,
2073 ">>> TXATTRCREATE fid %d name %s size %llu flag %d\n",
2074 fid->fid, name, attr_size, flags);
2075 clnt = fid->clnt;
2076 req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
2077 fid->fid, name, attr_size, flags);
2078 if (IS_ERR(req)) {
2079 err = PTR_ERR(req);
2080 goto error;
2081 }
2082 p9_debug(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);
2083 p9_req_put(clnt, req);
2084 error:
2085 return err;
2086 }
2087 EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
2088
2089 int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
2090 {
2091 int err, rsize, non_zc = 0;
2092 struct p9_client *clnt;
2093 struct p9_req_t *req;
2094 char *dataptr;
2095 struct kvec kv = {.iov_base = data, .iov_len = count};
2096 struct iov_iter to;
2097
2098 iov_iter_kvec(&to, ITER_DEST, &kv, 1, count);
2099
2100 p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
2101 fid->fid, offset, count);
2102
2103 clnt = fid->clnt;
2104
2105 rsize = fid->iounit;
2106 if (!rsize || rsize > clnt->msize - P9_READDIRHDRSZ)
2107 rsize = clnt->msize - P9_READDIRHDRSZ;
2108
2109 if (count < rsize)
2110 rsize = count;
2111
2112 /* Don't bother zerocopy for small IO (< 1024) */
2113 if (clnt->trans_mod->zc_request && rsize > 1024) {
2114 /* response header len is 11
2115 * PDU Header(7) + IO Size (4)
2116 */
2117 req = p9_client_zc_rpc(clnt, P9_TREADDIR, &to, NULL, rsize, 0,
2118 11, "dqd", fid->fid, offset, rsize);
2119 } else {
2120 non_zc = 1;
2121 req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid,
2122 offset, rsize);
2123 }
2124 if (IS_ERR(req)) {
2125 err = PTR_ERR(req);
2126 goto error;
2127 }
2128
2129 err = p9pdu_readf(&req->rc, clnt->proto_version, "D", &count, &dataptr);
2130 if (err) {
2131 trace_9p_protocol_dump(clnt, &req->rc);
2132 goto free_and_error;
2133 }
2134 if (rsize < count) {
2135 pr_err("bogus RREADDIR count (%d > %d)\n", count, rsize);
2136 count = rsize;
2137 }
2138
2139 p9_debug(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);
2140
2141 if (non_zc)
2142 memmove(data, dataptr, count);
2143
2144 p9_req_put(clnt, req);
2145 return count;
2146
2147 free_and_error:
2148 p9_req_put(clnt, req);
2149 error:
2150 return err;
2151 }
2152 EXPORT_SYMBOL(p9_client_readdir);
2153
2154 int p9_client_mknod_dotl(struct p9_fid *fid, const char *name, int mode,
2155 dev_t rdev, kgid_t gid, struct p9_qid *qid)
2156 {
2157 int err;
2158 struct p9_client *clnt;
2159 struct p9_req_t *req;
2160
2161 clnt = fid->clnt;
2162 p9_debug(P9_DEBUG_9P,
2163 ">>> TMKNOD fid %d name %s mode %d major %d minor %d\n",
2164 fid->fid, name, mode, MAJOR(rdev), MINOR(rdev));
2165 req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddg", fid->fid, name, mode,
2166 MAJOR(rdev), MINOR(rdev), gid);
2167 if (IS_ERR(req))
2168 return PTR_ERR(req);
2169
2170 err = p9pdu_readf(&req->rc, clnt->proto_version, "Q", qid);
2171 if (err) {
2172 trace_9p_protocol_dump(clnt, &req->rc);
2173 goto error;
2174 }
2175 p9_debug(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n",
2176 qid->type, qid->path, qid->version);
2177
2178 error:
2179 p9_req_put(clnt, req);
2180 return err;
2181 }
2182 EXPORT_SYMBOL(p9_client_mknod_dotl);
2183
2184 int p9_client_mkdir_dotl(struct p9_fid *fid, const char *name, int mode,
2185 kgid_t gid, struct p9_qid *qid)
2186 {
2187 int err;
2188 struct p9_client *clnt;
2189 struct p9_req_t *req;
2190
2191 clnt = fid->clnt;
2192 p9_debug(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
2193 fid->fid, name, mode, from_kgid(&init_user_ns, gid));
2194 req = p9_client_rpc(clnt, P9_TMKDIR, "dsdg",
2195 fid->fid, name, mode, gid);
2196 if (IS_ERR(req))
2197 return PTR_ERR(req);
2198
2199 err = p9pdu_readf(&req->rc, clnt->proto_version, "Q", qid);
2200 if (err) {
2201 trace_9p_protocol_dump(clnt, &req->rc);
2202 goto error;
2203 }
2204 p9_debug(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type,
2205 qid->path, qid->version);
2206
2207 error:
2208 p9_req_put(clnt, req);
2209 return err;
2210 }
2211 EXPORT_SYMBOL(p9_client_mkdir_dotl);
2212
2213 int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status)
2214 {
2215 int err;
2216 struct p9_client *clnt;
2217 struct p9_req_t *req;
2218
2219 clnt = fid->clnt;
2220 p9_debug(P9_DEBUG_9P,
2221 ">>> TLOCK fid %d type %i flags %d start %lld length %lld proc_id %d client_id %s\n",
2222 fid->fid, flock->type, flock->flags, flock->start,
2223 flock->length, flock->proc_id, flock->client_id);
2224
2225 req = p9_client_rpc(clnt, P9_TLOCK, "dbdqqds", fid->fid, flock->type,
2226 flock->flags, flock->start, flock->length,
2227 flock->proc_id, flock->client_id);
2228
2229 if (IS_ERR(req))
2230 return PTR_ERR(req);
2231
2232 err = p9pdu_readf(&req->rc, clnt->proto_version, "b", status);
2233 if (err) {
2234 trace_9p_protocol_dump(clnt, &req->rc);
2235 goto error;
2236 }
2237 p9_debug(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status);
2238 error:
2239 p9_req_put(clnt, req);
2240 return err;
2241 }
2242 EXPORT_SYMBOL(p9_client_lock_dotl);
2243
2244 int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock)
2245 {
2246 int err;
2247 struct p9_client *clnt;
2248 struct p9_req_t *req;
2249
2250 clnt = fid->clnt;
2251 p9_debug(P9_DEBUG_9P,
2252 ">>> TGETLOCK fid %d, type %i start %lld length %lld proc_id %d client_id %s\n",
2253 fid->fid, glock->type, glock->start, glock->length,
2254 glock->proc_id, glock->client_id);
2255
2256 req = p9_client_rpc(clnt, P9_TGETLOCK, "dbqqds", fid->fid,
2257 glock->type, glock->start, glock->length,
2258 glock->proc_id, glock->client_id);
2259
2260 if (IS_ERR(req))
2261 return PTR_ERR(req);
2262
2263 err = p9pdu_readf(&req->rc, clnt->proto_version, "bqqds", &glock->type,
2264 &glock->start, &glock->length, &glock->proc_id,
2265 &glock->client_id);
2266 if (err) {
2267 trace_9p_protocol_dump(clnt, &req->rc);
2268 goto error;
2269 }
2270 p9_debug(P9_DEBUG_9P,
2271 "<<< RGETLOCK type %i start %lld length %lld proc_id %d client_id %s\n",
2272 glock->type, glock->start, glock->length,
2273 glock->proc_id, glock->client_id);
2274 error:
2275 p9_req_put(clnt, req);
2276 return err;
2277 }
2278 EXPORT_SYMBOL(p9_client_getlock_dotl);
2279
2280 int p9_client_readlink(struct p9_fid *fid, char **target)
2281 {
2282 int err;
2283 struct p9_client *clnt;
2284 struct p9_req_t *req;
2285
2286 clnt = fid->clnt;
2287 p9_debug(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid);
2288
2289 req = p9_client_rpc(clnt, P9_TREADLINK, "d", fid->fid);
2290 if (IS_ERR(req))
2291 return PTR_ERR(req);
2292
2293 err = p9pdu_readf(&req->rc, clnt->proto_version, "s", target);
2294 if (err) {
2295 trace_9p_protocol_dump(clnt, &req->rc);
2296 goto error;
2297 }
2298 p9_debug(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target);
2299 error:
2300 p9_req_put(clnt, req);
2301 return err;
2302 }
2303 EXPORT_SYMBOL(p9_client_readlink);
2304
2305 int __init p9_client_init(void)
2306 {
2307 p9_req_cache = KMEM_CACHE(p9_req_t, SLAB_TYPESAFE_BY_RCU);
2308 return p9_req_cache ? 0 : -ENOMEM;
2309 }
2310
2311 void __exit p9_client_exit(void)
2312 {
2313 kmem_cache_destroy(p9_req_cache);
2314 }
2315
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.