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

source code of linux/net/9p/client.c