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334f485d
MS
1/*
2 FUSE: Filesystem in Userspace
1729a16c 3 Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu>
334f485d
MS
4
5 This program can be distributed under the terms of the GNU GPL.
6 See the file COPYING.
7*/
8
9#include "fuse_i.h"
10
11#include <linux/init.h>
12#include <linux/module.h>
13#include <linux/poll.h>
14#include <linux/uio.h>
15#include <linux/miscdevice.h>
16#include <linux/pagemap.h>
17#include <linux/file.h>
18#include <linux/slab.h>
dd3bb14f 19#include <linux/pipe_fs_i.h>
ce534fb0
MS
20#include <linux/swap.h>
21#include <linux/splice.h>
334f485d
MS
22
23MODULE_ALIAS_MISCDEV(FUSE_MINOR);
578454ff 24MODULE_ALIAS("devname:fuse");
334f485d 25
e18b890b 26static struct kmem_cache *fuse_req_cachep;
334f485d 27
8bfc016d 28static struct fuse_conn *fuse_get_conn(struct file *file)
334f485d 29{
0720b315
MS
30 /*
31 * Lockless access is OK, because file->private data is set
32 * once during mount and is valid until the file is released.
33 */
34 return file->private_data;
334f485d
MS
35}
36
8bfc016d 37static void fuse_request_init(struct fuse_req *req)
334f485d
MS
38{
39 memset(req, 0, sizeof(*req));
40 INIT_LIST_HEAD(&req->list);
a4d27e75 41 INIT_LIST_HEAD(&req->intr_entry);
334f485d
MS
42 init_waitqueue_head(&req->waitq);
43 atomic_set(&req->count, 1);
44}
45
46struct fuse_req *fuse_request_alloc(void)
47{
e94b1766 48 struct fuse_req *req = kmem_cache_alloc(fuse_req_cachep, GFP_KERNEL);
334f485d
MS
49 if (req)
50 fuse_request_init(req);
51 return req;
52}
08cbf542 53EXPORT_SYMBOL_GPL(fuse_request_alloc);
334f485d 54
3be5a52b
MS
55struct fuse_req *fuse_request_alloc_nofs(void)
56{
57 struct fuse_req *req = kmem_cache_alloc(fuse_req_cachep, GFP_NOFS);
58 if (req)
59 fuse_request_init(req);
60 return req;
61}
62
334f485d
MS
63void fuse_request_free(struct fuse_req *req)
64{
65 kmem_cache_free(fuse_req_cachep, req);
66}
67
8bfc016d 68static void block_sigs(sigset_t *oldset)
334f485d
MS
69{
70 sigset_t mask;
71
72 siginitsetinv(&mask, sigmask(SIGKILL));
73 sigprocmask(SIG_BLOCK, &mask, oldset);
74}
75
8bfc016d 76static void restore_sigs(sigset_t *oldset)
334f485d
MS
77{
78 sigprocmask(SIG_SETMASK, oldset, NULL);
79}
80
334f485d
MS
81static void __fuse_get_request(struct fuse_req *req)
82{
83 atomic_inc(&req->count);
84}
85
86/* Must be called with > 1 refcount */
87static void __fuse_put_request(struct fuse_req *req)
88{
89 BUG_ON(atomic_read(&req->count) < 2);
90 atomic_dec(&req->count);
91}
92
33649c91
MS
93static void fuse_req_init_context(struct fuse_req *req)
94{
2186a71c
DH
95 req->in.h.uid = current_fsuid();
96 req->in.h.gid = current_fsgid();
33649c91
MS
97 req->in.h.pid = current->pid;
98}
99
ce1d5a49 100struct fuse_req *fuse_get_req(struct fuse_conn *fc)
334f485d 101{
08a53cdc
MS
102 struct fuse_req *req;
103 sigset_t oldset;
9bc5ddda 104 int intr;
08a53cdc
MS
105 int err;
106
9bc5ddda 107 atomic_inc(&fc->num_waiting);
08a53cdc 108 block_sigs(&oldset);
9bc5ddda 109 intr = wait_event_interruptible(fc->blocked_waitq, !fc->blocked);
08a53cdc 110 restore_sigs(&oldset);
9bc5ddda
MS
111 err = -EINTR;
112 if (intr)
113 goto out;
08a53cdc 114
51eb01e7
MS
115 err = -ENOTCONN;
116 if (!fc->connected)
117 goto out;
118
08a53cdc 119 req = fuse_request_alloc();
9bc5ddda 120 err = -ENOMEM;
ce1d5a49 121 if (!req)
9bc5ddda 122 goto out;
334f485d 123
33649c91 124 fuse_req_init_context(req);
9bc5ddda 125 req->waiting = 1;
334f485d 126 return req;
9bc5ddda
MS
127
128 out:
129 atomic_dec(&fc->num_waiting);
130 return ERR_PTR(err);
334f485d 131}
08cbf542 132EXPORT_SYMBOL_GPL(fuse_get_req);
334f485d 133
33649c91
MS
134/*
135 * Return request in fuse_file->reserved_req. However that may
136 * currently be in use. If that is the case, wait for it to become
137 * available.
138 */
139static struct fuse_req *get_reserved_req(struct fuse_conn *fc,
140 struct file *file)
141{
142 struct fuse_req *req = NULL;
143 struct fuse_file *ff = file->private_data;
144
145 do {
de5e3dec 146 wait_event(fc->reserved_req_waitq, ff->reserved_req);
33649c91
MS
147 spin_lock(&fc->lock);
148 if (ff->reserved_req) {
149 req = ff->reserved_req;
150 ff->reserved_req = NULL;
151 get_file(file);
152 req->stolen_file = file;
153 }
154 spin_unlock(&fc->lock);
155 } while (!req);
156
157 return req;
158}
159
160/*
161 * Put stolen request back into fuse_file->reserved_req
162 */
163static void put_reserved_req(struct fuse_conn *fc, struct fuse_req *req)
164{
165 struct file *file = req->stolen_file;
166 struct fuse_file *ff = file->private_data;
167
168 spin_lock(&fc->lock);
169 fuse_request_init(req);
170 BUG_ON(ff->reserved_req);
171 ff->reserved_req = req;
de5e3dec 172 wake_up_all(&fc->reserved_req_waitq);
33649c91
MS
173 spin_unlock(&fc->lock);
174 fput(file);
175}
176
177/*
178 * Gets a requests for a file operation, always succeeds
179 *
180 * This is used for sending the FLUSH request, which must get to
181 * userspace, due to POSIX locks which may need to be unlocked.
182 *
183 * If allocation fails due to OOM, use the reserved request in
184 * fuse_file.
185 *
186 * This is very unlikely to deadlock accidentally, since the
187 * filesystem should not have it's own file open. If deadlock is
188 * intentional, it can still be broken by "aborting" the filesystem.
189 */
190struct fuse_req *fuse_get_req_nofail(struct fuse_conn *fc, struct file *file)
191{
192 struct fuse_req *req;
193
194 atomic_inc(&fc->num_waiting);
195 wait_event(fc->blocked_waitq, !fc->blocked);
196 req = fuse_request_alloc();
197 if (!req)
198 req = get_reserved_req(fc, file);
199
200 fuse_req_init_context(req);
201 req->waiting = 1;
202 return req;
203}
204
334f485d 205void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req)
7128ec2a
MS
206{
207 if (atomic_dec_and_test(&req->count)) {
9bc5ddda
MS
208 if (req->waiting)
209 atomic_dec(&fc->num_waiting);
33649c91
MS
210
211 if (req->stolen_file)
212 put_reserved_req(fc, req);
213 else
214 fuse_request_free(req);
7128ec2a
MS
215 }
216}
08cbf542 217EXPORT_SYMBOL_GPL(fuse_put_request);
7128ec2a 218
d12def1b
MS
219static unsigned len_args(unsigned numargs, struct fuse_arg *args)
220{
221 unsigned nbytes = 0;
222 unsigned i;
223
224 for (i = 0; i < numargs; i++)
225 nbytes += args[i].size;
226
227 return nbytes;
228}
229
230static u64 fuse_get_unique(struct fuse_conn *fc)
231{
232 fc->reqctr++;
233 /* zero is special */
234 if (fc->reqctr == 0)
235 fc->reqctr = 1;
236
237 return fc->reqctr;
238}
239
240static void queue_request(struct fuse_conn *fc, struct fuse_req *req)
241{
d12def1b
MS
242 req->in.h.len = sizeof(struct fuse_in_header) +
243 len_args(req->in.numargs, (struct fuse_arg *) req->in.args);
244 list_add_tail(&req->list, &fc->pending);
245 req->state = FUSE_REQ_PENDING;
246 if (!req->waiting) {
247 req->waiting = 1;
248 atomic_inc(&fc->num_waiting);
249 }
250 wake_up(&fc->waitq);
251 kill_fasync(&fc->fasync, SIGIO, POLL_IN);
252}
253
07e77dca
MS
254void fuse_queue_forget(struct fuse_conn *fc, struct fuse_forget_link *forget,
255 u64 nodeid, u64 nlookup)
256{
02c048b9
MS
257 forget->forget_one.nodeid = nodeid;
258 forget->forget_one.nlookup = nlookup;
07e77dca
MS
259
260 spin_lock(&fc->lock);
261 fc->forget_list_tail->next = forget;
262 fc->forget_list_tail = forget;
263 wake_up(&fc->waitq);
264 kill_fasync(&fc->fasync, SIGIO, POLL_IN);
265 spin_unlock(&fc->lock);
266}
267
d12def1b
MS
268static void flush_bg_queue(struct fuse_conn *fc)
269{
7a6d3c8b 270 while (fc->active_background < fc->max_background &&
d12def1b
MS
271 !list_empty(&fc->bg_queue)) {
272 struct fuse_req *req;
273
274 req = list_entry(fc->bg_queue.next, struct fuse_req, list);
275 list_del(&req->list);
276 fc->active_background++;
2d45ba38 277 req->in.h.unique = fuse_get_unique(fc);
d12def1b
MS
278 queue_request(fc, req);
279 }
280}
281
334f485d
MS
282/*
283 * This function is called when a request is finished. Either a reply
f9a2842e 284 * has arrived or it was aborted (and not yet sent) or some error
f43b155a 285 * occurred during communication with userspace, or the device file
51eb01e7
MS
286 * was closed. The requester thread is woken up (if still waiting),
287 * the 'end' callback is called if given, else the reference to the
288 * request is released
7128ec2a 289 *
d7133114 290 * Called with fc->lock, unlocks it
334f485d
MS
291 */
292static void request_end(struct fuse_conn *fc, struct fuse_req *req)
b9ca67b2 293__releases(fc->lock)
334f485d 294{
51eb01e7
MS
295 void (*end) (struct fuse_conn *, struct fuse_req *) = req->end;
296 req->end = NULL;
d77a1d5b 297 list_del(&req->list);
a4d27e75 298 list_del(&req->intr_entry);
83cfd493 299 req->state = FUSE_REQ_FINISHED;
51eb01e7 300 if (req->background) {
7a6d3c8b 301 if (fc->num_background == fc->max_background) {
51eb01e7
MS
302 fc->blocked = 0;
303 wake_up_all(&fc->blocked_waitq);
304 }
7a6d3c8b 305 if (fc->num_background == fc->congestion_threshold &&
a325f9b9 306 fc->connected && fc->bdi_initialized) {
8aa7e847
JA
307 clear_bdi_congested(&fc->bdi, BLK_RW_SYNC);
308 clear_bdi_congested(&fc->bdi, BLK_RW_ASYNC);
f92b99b9 309 }
51eb01e7 310 fc->num_background--;
d12def1b
MS
311 fc->active_background--;
312 flush_bg_queue(fc);
334f485d 313 }
51eb01e7 314 spin_unlock(&fc->lock);
51eb01e7
MS
315 wake_up(&req->waitq);
316 if (end)
317 end(fc, req);
e9bb09dd 318 fuse_put_request(fc, req);
334f485d
MS
319}
320
a4d27e75
MS
321static void wait_answer_interruptible(struct fuse_conn *fc,
322 struct fuse_req *req)
b9ca67b2
MS
323__releases(fc->lock)
324__acquires(fc->lock)
a4d27e75
MS
325{
326 if (signal_pending(current))
327 return;
328
329 spin_unlock(&fc->lock);
330 wait_event_interruptible(req->waitq, req->state == FUSE_REQ_FINISHED);
331 spin_lock(&fc->lock);
332}
333
334static void queue_interrupt(struct fuse_conn *fc, struct fuse_req *req)
335{
336 list_add_tail(&req->intr_entry, &fc->interrupts);
337 wake_up(&fc->waitq);
338 kill_fasync(&fc->fasync, SIGIO, POLL_IN);
339}
340
7c352bdf 341static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
b9ca67b2
MS
342__releases(fc->lock)
343__acquires(fc->lock)
334f485d 344{
a4d27e75
MS
345 if (!fc->no_interrupt) {
346 /* Any signal may interrupt this */
347 wait_answer_interruptible(fc, req);
334f485d 348
a4d27e75
MS
349 if (req->aborted)
350 goto aborted;
351 if (req->state == FUSE_REQ_FINISHED)
352 return;
353
354 req->interrupted = 1;
355 if (req->state == FUSE_REQ_SENT)
356 queue_interrupt(fc, req);
357 }
358
a131de0a 359 if (!req->force) {
a4d27e75
MS
360 sigset_t oldset;
361
362 /* Only fatal signals may interrupt this */
51eb01e7 363 block_sigs(&oldset);
a4d27e75 364 wait_answer_interruptible(fc, req);
51eb01e7 365 restore_sigs(&oldset);
a131de0a
MS
366
367 if (req->aborted)
368 goto aborted;
369 if (req->state == FUSE_REQ_FINISHED)
370 return;
371
372 /* Request is not yet in userspace, bail out */
373 if (req->state == FUSE_REQ_PENDING) {
374 list_del(&req->list);
375 __fuse_put_request(req);
376 req->out.h.error = -EINTR;
377 return;
378 }
51eb01e7 379 }
334f485d 380
a131de0a
MS
381 /*
382 * Either request is already in userspace, or it was forced.
383 * Wait it out.
384 */
385 spin_unlock(&fc->lock);
386 wait_event(req->waitq, req->state == FUSE_REQ_FINISHED);
387 spin_lock(&fc->lock);
a4d27e75 388
a131de0a
MS
389 if (!req->aborted)
390 return;
a4d27e75
MS
391
392 aborted:
a131de0a 393 BUG_ON(req->state != FUSE_REQ_FINISHED);
334f485d
MS
394 if (req->locked) {
395 /* This is uninterruptible sleep, because data is
396 being copied to/from the buffers of req. During
397 locked state, there mustn't be any filesystem
398 operation (e.g. page fault), since that could lead
399 to deadlock */
d7133114 400 spin_unlock(&fc->lock);
334f485d 401 wait_event(req->waitq, !req->locked);
d7133114 402 spin_lock(&fc->lock);
334f485d 403 }
334f485d
MS
404}
405
b93f858a 406void fuse_request_send(struct fuse_conn *fc, struct fuse_req *req)
334f485d
MS
407{
408 req->isreply = 1;
d7133114 409 spin_lock(&fc->lock);
1e9a4ed9 410 if (!fc->connected)
334f485d
MS
411 req->out.h.error = -ENOTCONN;
412 else if (fc->conn_error)
413 req->out.h.error = -ECONNREFUSED;
414 else {
2d45ba38 415 req->in.h.unique = fuse_get_unique(fc);
334f485d
MS
416 queue_request(fc, req);
417 /* acquire extra reference, since request is still needed
418 after request_end() */
419 __fuse_get_request(req);
420
7c352bdf 421 request_wait_answer(fc, req);
334f485d 422 }
d7133114 423 spin_unlock(&fc->lock);
334f485d 424}
08cbf542 425EXPORT_SYMBOL_GPL(fuse_request_send);
334f485d 426
b93f858a
TH
427static void fuse_request_send_nowait_locked(struct fuse_conn *fc,
428 struct fuse_req *req)
d12def1b
MS
429{
430 req->background = 1;
431 fc->num_background++;
7a6d3c8b 432 if (fc->num_background == fc->max_background)
d12def1b 433 fc->blocked = 1;
7a6d3c8b 434 if (fc->num_background == fc->congestion_threshold &&
a325f9b9 435 fc->bdi_initialized) {
8aa7e847
JA
436 set_bdi_congested(&fc->bdi, BLK_RW_SYNC);
437 set_bdi_congested(&fc->bdi, BLK_RW_ASYNC);
d12def1b
MS
438 }
439 list_add_tail(&req->list, &fc->bg_queue);
440 flush_bg_queue(fc);
441}
442
b93f858a 443static void fuse_request_send_nowait(struct fuse_conn *fc, struct fuse_req *req)
334f485d 444{
d7133114 445 spin_lock(&fc->lock);
1e9a4ed9 446 if (fc->connected) {
b93f858a 447 fuse_request_send_nowait_locked(fc, req);
d7133114 448 spin_unlock(&fc->lock);
334f485d
MS
449 } else {
450 req->out.h.error = -ENOTCONN;
451 request_end(fc, req);
452 }
453}
454
b93f858a 455void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req)
334f485d
MS
456{
457 req->isreply = 1;
b93f858a 458 fuse_request_send_nowait(fc, req);
334f485d 459}
08cbf542 460EXPORT_SYMBOL_GPL(fuse_request_send_background);
334f485d 461
2d45ba38
MS
462static int fuse_request_send_notify_reply(struct fuse_conn *fc,
463 struct fuse_req *req, u64 unique)
464{
465 int err = -ENODEV;
466
467 req->isreply = 0;
468 req->in.h.unique = unique;
469 spin_lock(&fc->lock);
470 if (fc->connected) {
471 queue_request(fc, req);
472 err = 0;
473 }
474 spin_unlock(&fc->lock);
475
476 return err;
477}
478
3be5a52b
MS
479/*
480 * Called under fc->lock
481 *
482 * fc->connected must have been checked previously
483 */
b93f858a
TH
484void fuse_request_send_background_locked(struct fuse_conn *fc,
485 struct fuse_req *req)
3be5a52b
MS
486{
487 req->isreply = 1;
b93f858a 488 fuse_request_send_nowait_locked(fc, req);
3be5a52b
MS
489}
490
334f485d
MS
491/*
492 * Lock the request. Up to the next unlock_request() there mustn't be
493 * anything that could cause a page-fault. If the request was already
f9a2842e 494 * aborted bail out.
334f485d 495 */
d7133114 496static int lock_request(struct fuse_conn *fc, struct fuse_req *req)
334f485d
MS
497{
498 int err = 0;
499 if (req) {
d7133114 500 spin_lock(&fc->lock);
f9a2842e 501 if (req->aborted)
334f485d
MS
502 err = -ENOENT;
503 else
504 req->locked = 1;
d7133114 505 spin_unlock(&fc->lock);
334f485d
MS
506 }
507 return err;
508}
509
510/*
f9a2842e 511 * Unlock request. If it was aborted during being locked, the
334f485d
MS
512 * requester thread is currently waiting for it to be unlocked, so
513 * wake it up.
514 */
d7133114 515static void unlock_request(struct fuse_conn *fc, struct fuse_req *req)
334f485d
MS
516{
517 if (req) {
d7133114 518 spin_lock(&fc->lock);
334f485d 519 req->locked = 0;
f9a2842e 520 if (req->aborted)
334f485d 521 wake_up(&req->waitq);
d7133114 522 spin_unlock(&fc->lock);
334f485d
MS
523 }
524}
525
526struct fuse_copy_state {
d7133114 527 struct fuse_conn *fc;
334f485d
MS
528 int write;
529 struct fuse_req *req;
530 const struct iovec *iov;
dd3bb14f
MS
531 struct pipe_buffer *pipebufs;
532 struct pipe_buffer *currbuf;
533 struct pipe_inode_info *pipe;
334f485d
MS
534 unsigned long nr_segs;
535 unsigned long seglen;
536 unsigned long addr;
537 struct page *pg;
538 void *mapaddr;
539 void *buf;
540 unsigned len;
ce534fb0 541 unsigned move_pages:1;
334f485d
MS
542};
543
d7133114 544static void fuse_copy_init(struct fuse_copy_state *cs, struct fuse_conn *fc,
c3021629 545 int write,
d7133114 546 const struct iovec *iov, unsigned long nr_segs)
334f485d
MS
547{
548 memset(cs, 0, sizeof(*cs));
d7133114 549 cs->fc = fc;
334f485d 550 cs->write = write;
334f485d
MS
551 cs->iov = iov;
552 cs->nr_segs = nr_segs;
553}
554
555/* Unmap and put previous page of userspace buffer */
8bfc016d 556static void fuse_copy_finish(struct fuse_copy_state *cs)
334f485d 557{
dd3bb14f
MS
558 if (cs->currbuf) {
559 struct pipe_buffer *buf = cs->currbuf;
560
c3021629
MS
561 if (!cs->write) {
562 buf->ops->unmap(cs->pipe, buf, cs->mapaddr);
563 } else {
7909b1c6 564 kunmap(buf->page);
c3021629
MS
565 buf->len = PAGE_SIZE - cs->len;
566 }
dd3bb14f
MS
567 cs->currbuf = NULL;
568 cs->mapaddr = NULL;
569 } else if (cs->mapaddr) {
7909b1c6 570 kunmap(cs->pg);
334f485d
MS
571 if (cs->write) {
572 flush_dcache_page(cs->pg);
573 set_page_dirty_lock(cs->pg);
574 }
575 put_page(cs->pg);
576 cs->mapaddr = NULL;
577 }
578}
579
580/*
581 * Get another pagefull of userspace buffer, and map it to kernel
582 * address space, and lock request
583 */
584static int fuse_copy_fill(struct fuse_copy_state *cs)
585{
586 unsigned long offset;
587 int err;
588
d7133114 589 unlock_request(cs->fc, cs->req);
334f485d 590 fuse_copy_finish(cs);
dd3bb14f
MS
591 if (cs->pipebufs) {
592 struct pipe_buffer *buf = cs->pipebufs;
593
c3021629
MS
594 if (!cs->write) {
595 err = buf->ops->confirm(cs->pipe, buf);
596 if (err)
597 return err;
598
599 BUG_ON(!cs->nr_segs);
600 cs->currbuf = buf;
7909b1c6 601 cs->mapaddr = buf->ops->map(cs->pipe, buf, 0);
c3021629
MS
602 cs->len = buf->len;
603 cs->buf = cs->mapaddr + buf->offset;
604 cs->pipebufs++;
605 cs->nr_segs--;
606 } else {
607 struct page *page;
dd3bb14f 608
c3021629
MS
609 if (cs->nr_segs == cs->pipe->buffers)
610 return -EIO;
611
612 page = alloc_page(GFP_HIGHUSER);
613 if (!page)
614 return -ENOMEM;
615
616 buf->page = page;
617 buf->offset = 0;
618 buf->len = 0;
619
620 cs->currbuf = buf;
7909b1c6 621 cs->mapaddr = kmap(page);
c3021629
MS
622 cs->buf = cs->mapaddr;
623 cs->len = PAGE_SIZE;
624 cs->pipebufs++;
625 cs->nr_segs++;
626 }
dd3bb14f
MS
627 } else {
628 if (!cs->seglen) {
629 BUG_ON(!cs->nr_segs);
630 cs->seglen = cs->iov[0].iov_len;
631 cs->addr = (unsigned long) cs->iov[0].iov_base;
632 cs->iov++;
633 cs->nr_segs--;
634 }
635 err = get_user_pages_fast(cs->addr, 1, cs->write, &cs->pg);
636 if (err < 0)
637 return err;
638 BUG_ON(err != 1);
639 offset = cs->addr % PAGE_SIZE;
7909b1c6 640 cs->mapaddr = kmap(cs->pg);
dd3bb14f
MS
641 cs->buf = cs->mapaddr + offset;
642 cs->len = min(PAGE_SIZE - offset, cs->seglen);
643 cs->seglen -= cs->len;
644 cs->addr += cs->len;
334f485d 645 }
334f485d 646
d7133114 647 return lock_request(cs->fc, cs->req);
334f485d
MS
648}
649
650/* Do as much copy to/from userspace buffer as we can */
8bfc016d 651static int fuse_copy_do(struct fuse_copy_state *cs, void **val, unsigned *size)
334f485d
MS
652{
653 unsigned ncpy = min(*size, cs->len);
654 if (val) {
655 if (cs->write)
656 memcpy(cs->buf, *val, ncpy);
657 else
658 memcpy(*val, cs->buf, ncpy);
659 *val += ncpy;
660 }
661 *size -= ncpy;
662 cs->len -= ncpy;
663 cs->buf += ncpy;
664 return ncpy;
665}
666
ce534fb0
MS
667static int fuse_check_page(struct page *page)
668{
669 if (page_mapcount(page) ||
670 page->mapping != NULL ||
671 page_count(page) != 1 ||
672 (page->flags & PAGE_FLAGS_CHECK_AT_PREP &
673 ~(1 << PG_locked |
674 1 << PG_referenced |
675 1 << PG_uptodate |
676 1 << PG_lru |
677 1 << PG_active |
678 1 << PG_reclaim))) {
679 printk(KERN_WARNING "fuse: trying to steal weird page\n");
680 printk(KERN_WARNING " page=%p index=%li flags=%08lx, count=%i, mapcount=%i, mapping=%p\n", page, page->index, page->flags, page_count(page), page_mapcount(page), page->mapping);
681 return 1;
682 }
683 return 0;
684}
685
686static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)
687{
688 int err;
689 struct page *oldpage = *pagep;
690 struct page *newpage;
691 struct pipe_buffer *buf = cs->pipebufs;
692 struct address_space *mapping;
693 pgoff_t index;
694
695 unlock_request(cs->fc, cs->req);
696 fuse_copy_finish(cs);
697
698 err = buf->ops->confirm(cs->pipe, buf);
699 if (err)
700 return err;
701
702 BUG_ON(!cs->nr_segs);
703 cs->currbuf = buf;
704 cs->len = buf->len;
705 cs->pipebufs++;
706 cs->nr_segs--;
707
708 if (cs->len != PAGE_SIZE)
709 goto out_fallback;
710
711 if (buf->ops->steal(cs->pipe, buf) != 0)
712 goto out_fallback;
713
714 newpage = buf->page;
715
716 if (WARN_ON(!PageUptodate(newpage)))
717 return -EIO;
718
719 ClearPageMappedToDisk(newpage);
720
721 if (fuse_check_page(newpage) != 0)
722 goto out_fallback_unlock;
723
724 mapping = oldpage->mapping;
725 index = oldpage->index;
726
727 /*
728 * This is a new and locked page, it shouldn't be mapped or
729 * have any special flags on it
730 */
731 if (WARN_ON(page_mapped(oldpage)))
732 goto out_fallback_unlock;
733 if (WARN_ON(page_has_private(oldpage)))
734 goto out_fallback_unlock;
735 if (WARN_ON(PageDirty(oldpage) || PageWriteback(oldpage)))
736 goto out_fallback_unlock;
737 if (WARN_ON(PageMlocked(oldpage)))
738 goto out_fallback_unlock;
739
740 remove_from_page_cache(oldpage);
741 page_cache_release(oldpage);
742
743 err = add_to_page_cache_locked(newpage, mapping, index, GFP_KERNEL);
744 if (err) {
745 printk(KERN_WARNING "fuse_try_move_page: failed to add page");
746 goto out_fallback_unlock;
747 }
748 page_cache_get(newpage);
749
750 if (!(buf->flags & PIPE_BUF_FLAG_LRU))
751 lru_cache_add_file(newpage);
752
753 err = 0;
754 spin_lock(&cs->fc->lock);
755 if (cs->req->aborted)
756 err = -ENOENT;
757 else
758 *pagep = newpage;
759 spin_unlock(&cs->fc->lock);
760
761 if (err) {
762 unlock_page(newpage);
763 page_cache_release(newpage);
764 return err;
765 }
766
767 unlock_page(oldpage);
768 page_cache_release(oldpage);
769 cs->len = 0;
770
771 return 0;
772
773out_fallback_unlock:
774 unlock_page(newpage);
775out_fallback:
776 cs->mapaddr = buf->ops->map(cs->pipe, buf, 1);
777 cs->buf = cs->mapaddr + buf->offset;
778
779 err = lock_request(cs->fc, cs->req);
780 if (err)
781 return err;
782
783 return 1;
784}
785
c3021629
MS
786static int fuse_ref_page(struct fuse_copy_state *cs, struct page *page,
787 unsigned offset, unsigned count)
788{
789 struct pipe_buffer *buf;
790
791 if (cs->nr_segs == cs->pipe->buffers)
792 return -EIO;
793
794 unlock_request(cs->fc, cs->req);
795 fuse_copy_finish(cs);
796
797 buf = cs->pipebufs;
798 page_cache_get(page);
799 buf->page = page;
800 buf->offset = offset;
801 buf->len = count;
802
803 cs->pipebufs++;
804 cs->nr_segs++;
805 cs->len = 0;
806
807 return 0;
808}
809
334f485d
MS
810/*
811 * Copy a page in the request to/from the userspace buffer. Must be
812 * done atomically
813 */
ce534fb0 814static int fuse_copy_page(struct fuse_copy_state *cs, struct page **pagep,
8bfc016d 815 unsigned offset, unsigned count, int zeroing)
334f485d 816{
ce534fb0
MS
817 int err;
818 struct page *page = *pagep;
819
b6777c40
MS
820 if (page && zeroing && count < PAGE_SIZE)
821 clear_highpage(page);
822
334f485d 823 while (count) {
c3021629
MS
824 if (cs->write && cs->pipebufs && page) {
825 return fuse_ref_page(cs, page, offset, count);
826 } else if (!cs->len) {
ce534fb0
MS
827 if (cs->move_pages && page &&
828 offset == 0 && count == PAGE_SIZE) {
829 err = fuse_try_move_page(cs, pagep);
830 if (err <= 0)
831 return err;
832 } else {
833 err = fuse_copy_fill(cs);
834 if (err)
835 return err;
836 }
1729a16c 837 }
334f485d 838 if (page) {
b6777c40 839 void *mapaddr = kmap_atomic(page, KM_USER0);
334f485d
MS
840 void *buf = mapaddr + offset;
841 offset += fuse_copy_do(cs, &buf, &count);
b6777c40 842 kunmap_atomic(mapaddr, KM_USER0);
334f485d
MS
843 } else
844 offset += fuse_copy_do(cs, NULL, &count);
845 }
846 if (page && !cs->write)
847 flush_dcache_page(page);
848 return 0;
849}
850
851/* Copy pages in the request to/from userspace buffer */
852static int fuse_copy_pages(struct fuse_copy_state *cs, unsigned nbytes,
853 int zeroing)
854{
855 unsigned i;
856 struct fuse_req *req = cs->req;
857 unsigned offset = req->page_offset;
858 unsigned count = min(nbytes, (unsigned) PAGE_SIZE - offset);
859
860 for (i = 0; i < req->num_pages && (nbytes || zeroing); i++) {
ce534fb0
MS
861 int err;
862
863 err = fuse_copy_page(cs, &req->pages[i], offset, count,
864 zeroing);
334f485d
MS
865 if (err)
866 return err;
867
868 nbytes -= count;
869 count = min(nbytes, (unsigned) PAGE_SIZE);
870 offset = 0;
871 }
872 return 0;
873}
874
875/* Copy a single argument in the request to/from userspace buffer */
876static int fuse_copy_one(struct fuse_copy_state *cs, void *val, unsigned size)
877{
878 while (size) {
1729a16c
MS
879 if (!cs->len) {
880 int err = fuse_copy_fill(cs);
881 if (err)
882 return err;
883 }
334f485d
MS
884 fuse_copy_do(cs, &val, &size);
885 }
886 return 0;
887}
888
889/* Copy request arguments to/from userspace buffer */
890static int fuse_copy_args(struct fuse_copy_state *cs, unsigned numargs,
891 unsigned argpages, struct fuse_arg *args,
892 int zeroing)
893{
894 int err = 0;
895 unsigned i;
896
897 for (i = 0; !err && i < numargs; i++) {
898 struct fuse_arg *arg = &args[i];
899 if (i == numargs - 1 && argpages)
900 err = fuse_copy_pages(cs, arg->size, zeroing);
901 else
902 err = fuse_copy_one(cs, arg->value, arg->size);
903 }
904 return err;
905}
906
07e77dca
MS
907static int forget_pending(struct fuse_conn *fc)
908{
909 return fc->forget_list_head.next != NULL;
910}
911
a4d27e75
MS
912static int request_pending(struct fuse_conn *fc)
913{
07e77dca
MS
914 return !list_empty(&fc->pending) || !list_empty(&fc->interrupts) ||
915 forget_pending(fc);
a4d27e75
MS
916}
917
334f485d
MS
918/* Wait until a request is available on the pending list */
919static void request_wait(struct fuse_conn *fc)
b9ca67b2
MS
920__releases(fc->lock)
921__acquires(fc->lock)
334f485d
MS
922{
923 DECLARE_WAITQUEUE(wait, current);
924
925 add_wait_queue_exclusive(&fc->waitq, &wait);
a4d27e75 926 while (fc->connected && !request_pending(fc)) {
334f485d
MS
927 set_current_state(TASK_INTERRUPTIBLE);
928 if (signal_pending(current))
929 break;
930
d7133114 931 spin_unlock(&fc->lock);
334f485d 932 schedule();
d7133114 933 spin_lock(&fc->lock);
334f485d
MS
934 }
935 set_current_state(TASK_RUNNING);
936 remove_wait_queue(&fc->waitq, &wait);
937}
938
a4d27e75
MS
939/*
940 * Transfer an interrupt request to userspace
941 *
942 * Unlike other requests this is assembled on demand, without a need
943 * to allocate a separate fuse_req structure.
944 *
945 * Called with fc->lock held, releases it
946 */
c3021629
MS
947static int fuse_read_interrupt(struct fuse_conn *fc, struct fuse_copy_state *cs,
948 size_t nbytes, struct fuse_req *req)
b9ca67b2 949__releases(fc->lock)
a4d27e75 950{
a4d27e75
MS
951 struct fuse_in_header ih;
952 struct fuse_interrupt_in arg;
953 unsigned reqsize = sizeof(ih) + sizeof(arg);
954 int err;
955
956 list_del_init(&req->intr_entry);
957 req->intr_unique = fuse_get_unique(fc);
958 memset(&ih, 0, sizeof(ih));
959 memset(&arg, 0, sizeof(arg));
960 ih.len = reqsize;
961 ih.opcode = FUSE_INTERRUPT;
962 ih.unique = req->intr_unique;
963 arg.unique = req->in.h.unique;
964
965 spin_unlock(&fc->lock);
c3021629 966 if (nbytes < reqsize)
a4d27e75
MS
967 return -EINVAL;
968
c3021629 969 err = fuse_copy_one(cs, &ih, sizeof(ih));
a4d27e75 970 if (!err)
c3021629
MS
971 err = fuse_copy_one(cs, &arg, sizeof(arg));
972 fuse_copy_finish(cs);
a4d27e75
MS
973
974 return err ? err : reqsize;
975}
976
02c048b9
MS
977static struct fuse_forget_link *dequeue_forget(struct fuse_conn *fc,
978 unsigned max,
979 unsigned *countp)
07e77dca 980{
02c048b9
MS
981 struct fuse_forget_link *head = fc->forget_list_head.next;
982 struct fuse_forget_link **newhead = &head;
983 unsigned count;
07e77dca 984
02c048b9
MS
985 for (count = 0; *newhead != NULL && count < max; count++)
986 newhead = &(*newhead)->next;
987
988 fc->forget_list_head.next = *newhead;
989 *newhead = NULL;
07e77dca
MS
990 if (fc->forget_list_head.next == NULL)
991 fc->forget_list_tail = &fc->forget_list_head;
992
02c048b9
MS
993 if (countp != NULL)
994 *countp = count;
995
996 return head;
07e77dca
MS
997}
998
999static int fuse_read_single_forget(struct fuse_conn *fc,
1000 struct fuse_copy_state *cs,
1001 size_t nbytes)
1002__releases(fc->lock)
1003{
1004 int err;
02c048b9 1005 struct fuse_forget_link *forget = dequeue_forget(fc, 1, NULL);
07e77dca 1006 struct fuse_forget_in arg = {
02c048b9 1007 .nlookup = forget->forget_one.nlookup,
07e77dca
MS
1008 };
1009 struct fuse_in_header ih = {
1010 .opcode = FUSE_FORGET,
02c048b9 1011 .nodeid = forget->forget_one.nodeid,
07e77dca
MS
1012 .unique = fuse_get_unique(fc),
1013 .len = sizeof(ih) + sizeof(arg),
1014 };
1015
1016 spin_unlock(&fc->lock);
1017 kfree(forget);
1018 if (nbytes < ih.len)
1019 return -EINVAL;
1020
1021 err = fuse_copy_one(cs, &ih, sizeof(ih));
1022 if (!err)
1023 err = fuse_copy_one(cs, &arg, sizeof(arg));
1024 fuse_copy_finish(cs);
1025
1026 if (err)
1027 return err;
1028
1029 return ih.len;
1030}
1031
02c048b9
MS
1032static int fuse_read_batch_forget(struct fuse_conn *fc,
1033 struct fuse_copy_state *cs, size_t nbytes)
1034__releases(fc->lock)
1035{
1036 int err;
1037 unsigned max_forgets;
1038 unsigned count;
1039 struct fuse_forget_link *head;
1040 struct fuse_batch_forget_in arg = { .count = 0 };
1041 struct fuse_in_header ih = {
1042 .opcode = FUSE_BATCH_FORGET,
1043 .unique = fuse_get_unique(fc),
1044 .len = sizeof(ih) + sizeof(arg),
1045 };
1046
1047 if (nbytes < ih.len) {
1048 spin_unlock(&fc->lock);
1049 return -EINVAL;
1050 }
1051
1052 max_forgets = (nbytes - ih.len) / sizeof(struct fuse_forget_one);
1053 head = dequeue_forget(fc, max_forgets, &count);
1054 spin_unlock(&fc->lock);
1055
1056 arg.count = count;
1057 ih.len += count * sizeof(struct fuse_forget_one);
1058 err = fuse_copy_one(cs, &ih, sizeof(ih));
1059 if (!err)
1060 err = fuse_copy_one(cs, &arg, sizeof(arg));
1061
1062 while (head) {
1063 struct fuse_forget_link *forget = head;
1064
1065 if (!err) {
1066 err = fuse_copy_one(cs, &forget->forget_one,
1067 sizeof(forget->forget_one));
1068 }
1069 head = forget->next;
1070 kfree(forget);
1071 }
1072
1073 fuse_copy_finish(cs);
1074
1075 if (err)
1076 return err;
1077
1078 return ih.len;
1079}
1080
1081static int fuse_read_forget(struct fuse_conn *fc, struct fuse_copy_state *cs,
1082 size_t nbytes)
1083__releases(fc->lock)
1084{
1085 if (fc->minor < 16 || fc->forget_list_head.next->next == NULL)
1086 return fuse_read_single_forget(fc, cs, nbytes);
1087 else
1088 return fuse_read_batch_forget(fc, cs, nbytes);
1089}
1090
334f485d
MS
1091/*
1092 * Read a single request into the userspace filesystem's buffer. This
1093 * function waits until a request is available, then removes it from
1094 * the pending list and copies request data to userspace buffer. If
f9a2842e
MS
1095 * no reply is needed (FORGET) or request has been aborted or there
1096 * was an error during the copying then it's finished by calling
334f485d
MS
1097 * request_end(). Otherwise add it to the processing list, and set
1098 * the 'sent' flag.
1099 */
c3021629
MS
1100static ssize_t fuse_dev_do_read(struct fuse_conn *fc, struct file *file,
1101 struct fuse_copy_state *cs, size_t nbytes)
334f485d
MS
1102{
1103 int err;
334f485d
MS
1104 struct fuse_req *req;
1105 struct fuse_in *in;
334f485d
MS
1106 unsigned reqsize;
1107
1d3d752b 1108 restart:
d7133114 1109 spin_lock(&fc->lock);
e5ac1d1e
JD
1110 err = -EAGAIN;
1111 if ((file->f_flags & O_NONBLOCK) && fc->connected &&
a4d27e75 1112 !request_pending(fc))
e5ac1d1e
JD
1113 goto err_unlock;
1114
334f485d
MS
1115 request_wait(fc);
1116 err = -ENODEV;
9ba7cbba 1117 if (!fc->connected)
334f485d
MS
1118 goto err_unlock;
1119 err = -ERESTARTSYS;
a4d27e75 1120 if (!request_pending(fc))
334f485d
MS
1121 goto err_unlock;
1122
a4d27e75
MS
1123 if (!list_empty(&fc->interrupts)) {
1124 req = list_entry(fc->interrupts.next, struct fuse_req,
1125 intr_entry);
c3021629 1126 return fuse_read_interrupt(fc, cs, nbytes, req);
a4d27e75
MS
1127 }
1128
07e77dca
MS
1129 if (forget_pending(fc)) {
1130 if (list_empty(&fc->pending) || fc->forget_batch-- > 0)
02c048b9 1131 return fuse_read_forget(fc, cs, nbytes);
07e77dca
MS
1132
1133 if (fc->forget_batch <= -8)
1134 fc->forget_batch = 16;
1135 }
1136
334f485d 1137 req = list_entry(fc->pending.next, struct fuse_req, list);
83cfd493 1138 req->state = FUSE_REQ_READING;
d77a1d5b 1139 list_move(&req->list, &fc->io);
334f485d
MS
1140
1141 in = &req->in;
1d3d752b
MS
1142 reqsize = in->h.len;
1143 /* If request is too large, reply with an error and restart the read */
c3021629 1144 if (nbytes < reqsize) {
1d3d752b
MS
1145 req->out.h.error = -EIO;
1146 /* SETXATTR is special, since it may contain too large data */
1147 if (in->h.opcode == FUSE_SETXATTR)
1148 req->out.h.error = -E2BIG;
1149 request_end(fc, req);
1150 goto restart;
334f485d 1151 }
d7133114 1152 spin_unlock(&fc->lock);
c3021629
MS
1153 cs->req = req;
1154 err = fuse_copy_one(cs, &in->h, sizeof(in->h));
1d3d752b 1155 if (!err)
c3021629 1156 err = fuse_copy_args(cs, in->numargs, in->argpages,
1d3d752b 1157 (struct fuse_arg *) in->args, 0);
c3021629 1158 fuse_copy_finish(cs);
d7133114 1159 spin_lock(&fc->lock);
334f485d 1160 req->locked = 0;
c9c9d7df
MS
1161 if (req->aborted) {
1162 request_end(fc, req);
1163 return -ENODEV;
1164 }
334f485d 1165 if (err) {
c9c9d7df 1166 req->out.h.error = -EIO;
334f485d
MS
1167 request_end(fc, req);
1168 return err;
1169 }
1170 if (!req->isreply)
1171 request_end(fc, req);
1172 else {
83cfd493 1173 req->state = FUSE_REQ_SENT;
d77a1d5b 1174 list_move_tail(&req->list, &fc->processing);
a4d27e75
MS
1175 if (req->interrupted)
1176 queue_interrupt(fc, req);
d7133114 1177 spin_unlock(&fc->lock);
334f485d
MS
1178 }
1179 return reqsize;
1180
1181 err_unlock:
d7133114 1182 spin_unlock(&fc->lock);
334f485d
MS
1183 return err;
1184}
1185
c3021629
MS
1186static ssize_t fuse_dev_read(struct kiocb *iocb, const struct iovec *iov,
1187 unsigned long nr_segs, loff_t pos)
1188{
1189 struct fuse_copy_state cs;
1190 struct file *file = iocb->ki_filp;
1191 struct fuse_conn *fc = fuse_get_conn(file);
1192 if (!fc)
1193 return -EPERM;
1194
1195 fuse_copy_init(&cs, fc, 1, iov, nr_segs);
1196
1197 return fuse_dev_do_read(fc, file, &cs, iov_length(iov, nr_segs));
1198}
1199
1200static int fuse_dev_pipe_buf_steal(struct pipe_inode_info *pipe,
1201 struct pipe_buffer *buf)
1202{
1203 return 1;
1204}
1205
1206static const struct pipe_buf_operations fuse_dev_pipe_buf_ops = {
1207 .can_merge = 0,
1208 .map = generic_pipe_buf_map,
1209 .unmap = generic_pipe_buf_unmap,
1210 .confirm = generic_pipe_buf_confirm,
1211 .release = generic_pipe_buf_release,
1212 .steal = fuse_dev_pipe_buf_steal,
1213 .get = generic_pipe_buf_get,
1214};
1215
1216static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos,
1217 struct pipe_inode_info *pipe,
1218 size_t len, unsigned int flags)
1219{
1220 int ret;
1221 int page_nr = 0;
1222 int do_wakeup = 0;
1223 struct pipe_buffer *bufs;
1224 struct fuse_copy_state cs;
1225 struct fuse_conn *fc = fuse_get_conn(in);
1226 if (!fc)
1227 return -EPERM;
1228
07e77dca 1229 bufs = kmalloc(pipe->buffers * sizeof(struct pipe_buffer), GFP_KERNEL);
c3021629
MS
1230 if (!bufs)
1231 return -ENOMEM;
1232
1233 fuse_copy_init(&cs, fc, 1, NULL, 0);
1234 cs.pipebufs = bufs;
1235 cs.pipe = pipe;
1236 ret = fuse_dev_do_read(fc, in, &cs, len);
1237 if (ret < 0)
1238 goto out;
1239
1240 ret = 0;
1241 pipe_lock(pipe);
1242
1243 if (!pipe->readers) {
1244 send_sig(SIGPIPE, current, 0);
1245 if (!ret)
1246 ret = -EPIPE;
1247 goto out_unlock;
1248 }
1249
1250 if (pipe->nrbufs + cs.nr_segs > pipe->buffers) {
1251 ret = -EIO;
1252 goto out_unlock;
1253 }
1254
1255 while (page_nr < cs.nr_segs) {
1256 int newbuf = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1);
1257 struct pipe_buffer *buf = pipe->bufs + newbuf;
1258
1259 buf->page = bufs[page_nr].page;
1260 buf->offset = bufs[page_nr].offset;
1261 buf->len = bufs[page_nr].len;
1262 buf->ops = &fuse_dev_pipe_buf_ops;
1263
1264 pipe->nrbufs++;
1265 page_nr++;
1266 ret += buf->len;
1267
1268 if (pipe->inode)
1269 do_wakeup = 1;
1270 }
1271
1272out_unlock:
1273 pipe_unlock(pipe);
1274
1275 if (do_wakeup) {
1276 smp_mb();
1277 if (waitqueue_active(&pipe->wait))
1278 wake_up_interruptible(&pipe->wait);
1279 kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
1280 }
1281
1282out:
1283 for (; page_nr < cs.nr_segs; page_nr++)
1284 page_cache_release(bufs[page_nr].page);
1285
1286 kfree(bufs);
1287 return ret;
1288}
1289
95668a69
TH
1290static int fuse_notify_poll(struct fuse_conn *fc, unsigned int size,
1291 struct fuse_copy_state *cs)
1292{
1293 struct fuse_notify_poll_wakeup_out outarg;
f6d47a17 1294 int err = -EINVAL;
95668a69
TH
1295
1296 if (size != sizeof(outarg))
f6d47a17 1297 goto err;
95668a69
TH
1298
1299 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1300 if (err)
f6d47a17 1301 goto err;
95668a69 1302
f6d47a17 1303 fuse_copy_finish(cs);
95668a69 1304 return fuse_notify_poll_wakeup(fc, &outarg);
f6d47a17
MS
1305
1306err:
1307 fuse_copy_finish(cs);
1308 return err;
95668a69
TH
1309}
1310
3b463ae0
JM
1311static int fuse_notify_inval_inode(struct fuse_conn *fc, unsigned int size,
1312 struct fuse_copy_state *cs)
1313{
1314 struct fuse_notify_inval_inode_out outarg;
1315 int err = -EINVAL;
1316
1317 if (size != sizeof(outarg))
1318 goto err;
1319
1320 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1321 if (err)
1322 goto err;
1323 fuse_copy_finish(cs);
1324
1325 down_read(&fc->killsb);
1326 err = -ENOENT;
b21dda43
MS
1327 if (fc->sb) {
1328 err = fuse_reverse_inval_inode(fc->sb, outarg.ino,
1329 outarg.off, outarg.len);
1330 }
3b463ae0
JM
1331 up_read(&fc->killsb);
1332 return err;
1333
1334err:
1335 fuse_copy_finish(cs);
1336 return err;
1337}
1338
1339static int fuse_notify_inval_entry(struct fuse_conn *fc, unsigned int size,
1340 struct fuse_copy_state *cs)
1341{
1342 struct fuse_notify_inval_entry_out outarg;
b2d82ee3
FW
1343 int err = -ENOMEM;
1344 char *buf;
3b463ae0
JM
1345 struct qstr name;
1346
b2d82ee3
FW
1347 buf = kzalloc(FUSE_NAME_MAX + 1, GFP_KERNEL);
1348 if (!buf)
1349 goto err;
1350
1351 err = -EINVAL;
3b463ae0
JM
1352 if (size < sizeof(outarg))
1353 goto err;
1354
1355 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1356 if (err)
1357 goto err;
1358
1359 err = -ENAMETOOLONG;
1360 if (outarg.namelen > FUSE_NAME_MAX)
1361 goto err;
1362
1363 name.name = buf;
1364 name.len = outarg.namelen;
1365 err = fuse_copy_one(cs, buf, outarg.namelen + 1);
1366 if (err)
1367 goto err;
1368 fuse_copy_finish(cs);
1369 buf[outarg.namelen] = 0;
1370 name.hash = full_name_hash(name.name, name.len);
1371
1372 down_read(&fc->killsb);
1373 err = -ENOENT;
b21dda43
MS
1374 if (fc->sb)
1375 err = fuse_reverse_inval_entry(fc->sb, outarg.parent, &name);
3b463ae0 1376 up_read(&fc->killsb);
b2d82ee3 1377 kfree(buf);
3b463ae0
JM
1378 return err;
1379
1380err:
b2d82ee3 1381 kfree(buf);
3b463ae0
JM
1382 fuse_copy_finish(cs);
1383 return err;
1384}
1385
a1d75f25
MS
1386static int fuse_notify_store(struct fuse_conn *fc, unsigned int size,
1387 struct fuse_copy_state *cs)
1388{
1389 struct fuse_notify_store_out outarg;
1390 struct inode *inode;
1391 struct address_space *mapping;
1392 u64 nodeid;
1393 int err;
1394 pgoff_t index;
1395 unsigned int offset;
1396 unsigned int num;
1397 loff_t file_size;
1398 loff_t end;
1399
1400 err = -EINVAL;
1401 if (size < sizeof(outarg))
1402 goto out_finish;
1403
1404 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1405 if (err)
1406 goto out_finish;
1407
1408 err = -EINVAL;
1409 if (size - sizeof(outarg) != outarg.size)
1410 goto out_finish;
1411
1412 nodeid = outarg.nodeid;
1413
1414 down_read(&fc->killsb);
1415
1416 err = -ENOENT;
1417 if (!fc->sb)
1418 goto out_up_killsb;
1419
1420 inode = ilookup5(fc->sb, nodeid, fuse_inode_eq, &nodeid);
1421 if (!inode)
1422 goto out_up_killsb;
1423
1424 mapping = inode->i_mapping;
1425 index = outarg.offset >> PAGE_CACHE_SHIFT;
1426 offset = outarg.offset & ~PAGE_CACHE_MASK;
1427 file_size = i_size_read(inode);
1428 end = outarg.offset + outarg.size;
1429 if (end > file_size) {
1430 file_size = end;
1431 fuse_write_update_size(inode, file_size);
1432 }
1433
1434 num = outarg.size;
1435 while (num) {
1436 struct page *page;
1437 unsigned int this_num;
1438
1439 err = -ENOMEM;
1440 page = find_or_create_page(mapping, index,
1441 mapping_gfp_mask(mapping));
1442 if (!page)
1443 goto out_iput;
1444
1445 this_num = min_t(unsigned, num, PAGE_CACHE_SIZE - offset);
1446 err = fuse_copy_page(cs, &page, offset, this_num, 0);
1447 if (!err && offset == 0 && (num != 0 || file_size == end))
1448 SetPageUptodate(page);
1449 unlock_page(page);
1450 page_cache_release(page);
1451
1452 if (err)
1453 goto out_iput;
1454
1455 num -= this_num;
1456 offset = 0;
1457 index++;
1458 }
1459
1460 err = 0;
1461
1462out_iput:
1463 iput(inode);
1464out_up_killsb:
1465 up_read(&fc->killsb);
1466out_finish:
1467 fuse_copy_finish(cs);
1468 return err;
1469}
1470
2d45ba38
MS
1471static void fuse_retrieve_end(struct fuse_conn *fc, struct fuse_req *req)
1472{
0be8557b 1473 release_pages(req->pages, req->num_pages, 0);
2d45ba38
MS
1474}
1475
1476static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode,
1477 struct fuse_notify_retrieve_out *outarg)
1478{
1479 int err;
1480 struct address_space *mapping = inode->i_mapping;
1481 struct fuse_req *req;
1482 pgoff_t index;
1483 loff_t file_size;
1484 unsigned int num;
1485 unsigned int offset;
0157443c 1486 size_t total_len = 0;
2d45ba38
MS
1487
1488 req = fuse_get_req(fc);
1489 if (IS_ERR(req))
1490 return PTR_ERR(req);
1491
1492 offset = outarg->offset & ~PAGE_CACHE_MASK;
1493
1494 req->in.h.opcode = FUSE_NOTIFY_REPLY;
1495 req->in.h.nodeid = outarg->nodeid;
1496 req->in.numargs = 2;
1497 req->in.argpages = 1;
1498 req->page_offset = offset;
1499 req->end = fuse_retrieve_end;
1500
1501 index = outarg->offset >> PAGE_CACHE_SHIFT;
1502 file_size = i_size_read(inode);
1503 num = outarg->size;
1504 if (outarg->offset > file_size)
1505 num = 0;
1506 else if (outarg->offset + num > file_size)
1507 num = file_size - outarg->offset;
1508
1509 while (num) {
1510 struct page *page;
1511 unsigned int this_num;
1512
1513 page = find_get_page(mapping, index);
1514 if (!page)
1515 break;
1516
1517 this_num = min_t(unsigned, num, PAGE_CACHE_SIZE - offset);
1518 req->pages[req->num_pages] = page;
1519 req->num_pages++;
1520
1521 num -= this_num;
1522 total_len += this_num;
1523 }
1524 req->misc.retrieve_in.offset = outarg->offset;
1525 req->misc.retrieve_in.size = total_len;
1526 req->in.args[0].size = sizeof(req->misc.retrieve_in);
1527 req->in.args[0].value = &req->misc.retrieve_in;
1528 req->in.args[1].size = total_len;
1529
1530 err = fuse_request_send_notify_reply(fc, req, outarg->notify_unique);
1531 if (err)
1532 fuse_retrieve_end(fc, req);
1533
1534 return err;
1535}
1536
1537static int fuse_notify_retrieve(struct fuse_conn *fc, unsigned int size,
1538 struct fuse_copy_state *cs)
1539{
1540 struct fuse_notify_retrieve_out outarg;
1541 struct inode *inode;
1542 int err;
1543
1544 err = -EINVAL;
1545 if (size != sizeof(outarg))
1546 goto copy_finish;
1547
1548 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1549 if (err)
1550 goto copy_finish;
1551
1552 fuse_copy_finish(cs);
1553
1554 down_read(&fc->killsb);
1555 err = -ENOENT;
1556 if (fc->sb) {
1557 u64 nodeid = outarg.nodeid;
1558
1559 inode = ilookup5(fc->sb, nodeid, fuse_inode_eq, &nodeid);
1560 if (inode) {
1561 err = fuse_retrieve(fc, inode, &outarg);
1562 iput(inode);
1563 }
1564 }
1565 up_read(&fc->killsb);
1566
1567 return err;
1568
1569copy_finish:
1570 fuse_copy_finish(cs);
1571 return err;
1572}
1573
8599396b
TH
1574static int fuse_notify(struct fuse_conn *fc, enum fuse_notify_code code,
1575 unsigned int size, struct fuse_copy_state *cs)
1576{
1577 switch (code) {
95668a69
TH
1578 case FUSE_NOTIFY_POLL:
1579 return fuse_notify_poll(fc, size, cs);
1580
3b463ae0
JM
1581 case FUSE_NOTIFY_INVAL_INODE:
1582 return fuse_notify_inval_inode(fc, size, cs);
1583
1584 case FUSE_NOTIFY_INVAL_ENTRY:
1585 return fuse_notify_inval_entry(fc, size, cs);
1586
a1d75f25
MS
1587 case FUSE_NOTIFY_STORE:
1588 return fuse_notify_store(fc, size, cs);
1589
2d45ba38
MS
1590 case FUSE_NOTIFY_RETRIEVE:
1591 return fuse_notify_retrieve(fc, size, cs);
1592
8599396b 1593 default:
f6d47a17 1594 fuse_copy_finish(cs);
8599396b
TH
1595 return -EINVAL;
1596 }
1597}
1598
334f485d
MS
1599/* Look up request on processing list by unique ID */
1600static struct fuse_req *request_find(struct fuse_conn *fc, u64 unique)
1601{
1602 struct list_head *entry;
1603
1604 list_for_each(entry, &fc->processing) {
1605 struct fuse_req *req;
1606 req = list_entry(entry, struct fuse_req, list);
a4d27e75 1607 if (req->in.h.unique == unique || req->intr_unique == unique)
334f485d
MS
1608 return req;
1609 }
1610 return NULL;
1611}
1612
1613static int copy_out_args(struct fuse_copy_state *cs, struct fuse_out *out,
1614 unsigned nbytes)
1615{
1616 unsigned reqsize = sizeof(struct fuse_out_header);
1617
1618 if (out->h.error)
1619 return nbytes != reqsize ? -EINVAL : 0;
1620
1621 reqsize += len_args(out->numargs, out->args);
1622
1623 if (reqsize < nbytes || (reqsize > nbytes && !out->argvar))
1624 return -EINVAL;
1625 else if (reqsize > nbytes) {
1626 struct fuse_arg *lastarg = &out->args[out->numargs-1];
1627 unsigned diffsize = reqsize - nbytes;
1628 if (diffsize > lastarg->size)
1629 return -EINVAL;
1630 lastarg->size -= diffsize;
1631 }
1632 return fuse_copy_args(cs, out->numargs, out->argpages, out->args,
1633 out->page_zeroing);
1634}
1635
1636/*
1637 * Write a single reply to a request. First the header is copied from
1638 * the write buffer. The request is then searched on the processing
1639 * list by the unique ID found in the header. If found, then remove
1640 * it from the list and copy the rest of the buffer to the request.
1641 * The request is finished by calling request_end()
1642 */
dd3bb14f
MS
1643static ssize_t fuse_dev_do_write(struct fuse_conn *fc,
1644 struct fuse_copy_state *cs, size_t nbytes)
334f485d
MS
1645{
1646 int err;
334f485d
MS
1647 struct fuse_req *req;
1648 struct fuse_out_header oh;
334f485d 1649
334f485d
MS
1650 if (nbytes < sizeof(struct fuse_out_header))
1651 return -EINVAL;
1652
dd3bb14f 1653 err = fuse_copy_one(cs, &oh, sizeof(oh));
334f485d
MS
1654 if (err)
1655 goto err_finish;
8599396b
TH
1656
1657 err = -EINVAL;
1658 if (oh.len != nbytes)
1659 goto err_finish;
1660
1661 /*
1662 * Zero oh.unique indicates unsolicited notification message
1663 * and error contains notification code.
1664 */
1665 if (!oh.unique) {
dd3bb14f 1666 err = fuse_notify(fc, oh.error, nbytes - sizeof(oh), cs);
8599396b
TH
1667 return err ? err : nbytes;
1668 }
1669
334f485d 1670 err = -EINVAL;
8599396b 1671 if (oh.error <= -1000 || oh.error > 0)
334f485d
MS
1672 goto err_finish;
1673
d7133114 1674 spin_lock(&fc->lock);
69a53bf2
MS
1675 err = -ENOENT;
1676 if (!fc->connected)
1677 goto err_unlock;
1678
334f485d 1679 req = request_find(fc, oh.unique);
334f485d
MS
1680 if (!req)
1681 goto err_unlock;
1682
f9a2842e 1683 if (req->aborted) {
d7133114 1684 spin_unlock(&fc->lock);
dd3bb14f 1685 fuse_copy_finish(cs);
d7133114 1686 spin_lock(&fc->lock);
222f1d69 1687 request_end(fc, req);
334f485d
MS
1688 return -ENOENT;
1689 }
a4d27e75
MS
1690 /* Is it an interrupt reply? */
1691 if (req->intr_unique == oh.unique) {
1692 err = -EINVAL;
1693 if (nbytes != sizeof(struct fuse_out_header))
1694 goto err_unlock;
1695
1696 if (oh.error == -ENOSYS)
1697 fc->no_interrupt = 1;
1698 else if (oh.error == -EAGAIN)
1699 queue_interrupt(fc, req);
1700
1701 spin_unlock(&fc->lock);
dd3bb14f 1702 fuse_copy_finish(cs);
a4d27e75
MS
1703 return nbytes;
1704 }
1705
1706 req->state = FUSE_REQ_WRITING;
d77a1d5b 1707 list_move(&req->list, &fc->io);
334f485d
MS
1708 req->out.h = oh;
1709 req->locked = 1;
dd3bb14f 1710 cs->req = req;
ce534fb0
MS
1711 if (!req->out.page_replace)
1712 cs->move_pages = 0;
d7133114 1713 spin_unlock(&fc->lock);
334f485d 1714
dd3bb14f
MS
1715 err = copy_out_args(cs, &req->out, nbytes);
1716 fuse_copy_finish(cs);
334f485d 1717
d7133114 1718 spin_lock(&fc->lock);
334f485d
MS
1719 req->locked = 0;
1720 if (!err) {
f9a2842e 1721 if (req->aborted)
334f485d 1722 err = -ENOENT;
f9a2842e 1723 } else if (!req->aborted)
334f485d
MS
1724 req->out.h.error = -EIO;
1725 request_end(fc, req);
1726
1727 return err ? err : nbytes;
1728
1729 err_unlock:
d7133114 1730 spin_unlock(&fc->lock);
334f485d 1731 err_finish:
dd3bb14f 1732 fuse_copy_finish(cs);
334f485d
MS
1733 return err;
1734}
1735
dd3bb14f
MS
1736static ssize_t fuse_dev_write(struct kiocb *iocb, const struct iovec *iov,
1737 unsigned long nr_segs, loff_t pos)
1738{
1739 struct fuse_copy_state cs;
1740 struct fuse_conn *fc = fuse_get_conn(iocb->ki_filp);
1741 if (!fc)
1742 return -EPERM;
1743
c3021629 1744 fuse_copy_init(&cs, fc, 0, iov, nr_segs);
dd3bb14f
MS
1745
1746 return fuse_dev_do_write(fc, &cs, iov_length(iov, nr_segs));
1747}
1748
1749static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe,
1750 struct file *out, loff_t *ppos,
1751 size_t len, unsigned int flags)
1752{
1753 unsigned nbuf;
1754 unsigned idx;
1755 struct pipe_buffer *bufs;
1756 struct fuse_copy_state cs;
1757 struct fuse_conn *fc;
1758 size_t rem;
1759 ssize_t ret;
1760
1761 fc = fuse_get_conn(out);
1762 if (!fc)
1763 return -EPERM;
1764
07e77dca 1765 bufs = kmalloc(pipe->buffers * sizeof(struct pipe_buffer), GFP_KERNEL);
dd3bb14f
MS
1766 if (!bufs)
1767 return -ENOMEM;
1768
1769 pipe_lock(pipe);
1770 nbuf = 0;
1771 rem = 0;
1772 for (idx = 0; idx < pipe->nrbufs && rem < len; idx++)
1773 rem += pipe->bufs[(pipe->curbuf + idx) & (pipe->buffers - 1)].len;
1774
1775 ret = -EINVAL;
1776 if (rem < len) {
1777 pipe_unlock(pipe);
1778 goto out;
1779 }
1780
1781 rem = len;
1782 while (rem) {
1783 struct pipe_buffer *ibuf;
1784 struct pipe_buffer *obuf;
1785
1786 BUG_ON(nbuf >= pipe->buffers);
1787 BUG_ON(!pipe->nrbufs);
1788 ibuf = &pipe->bufs[pipe->curbuf];
1789 obuf = &bufs[nbuf];
1790
1791 if (rem >= ibuf->len) {
1792 *obuf = *ibuf;
1793 ibuf->ops = NULL;
1794 pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1);
1795 pipe->nrbufs--;
1796 } else {
1797 ibuf->ops->get(pipe, ibuf);
1798 *obuf = *ibuf;
1799 obuf->flags &= ~PIPE_BUF_FLAG_GIFT;
1800 obuf->len = rem;
1801 ibuf->offset += obuf->len;
1802 ibuf->len -= obuf->len;
1803 }
1804 nbuf++;
1805 rem -= obuf->len;
1806 }
1807 pipe_unlock(pipe);
1808
c3021629 1809 fuse_copy_init(&cs, fc, 0, NULL, nbuf);
dd3bb14f 1810 cs.pipebufs = bufs;
dd3bb14f
MS
1811 cs.pipe = pipe;
1812
ce534fb0
MS
1813 if (flags & SPLICE_F_MOVE)
1814 cs.move_pages = 1;
1815
dd3bb14f
MS
1816 ret = fuse_dev_do_write(fc, &cs, len);
1817
1818 for (idx = 0; idx < nbuf; idx++) {
1819 struct pipe_buffer *buf = &bufs[idx];
1820 buf->ops->release(pipe, buf);
1821 }
1822out:
1823 kfree(bufs);
1824 return ret;
1825}
1826
334f485d
MS
1827static unsigned fuse_dev_poll(struct file *file, poll_table *wait)
1828{
334f485d 1829 unsigned mask = POLLOUT | POLLWRNORM;
7025d9ad 1830 struct fuse_conn *fc = fuse_get_conn(file);
334f485d 1831 if (!fc)
7025d9ad 1832 return POLLERR;
334f485d
MS
1833
1834 poll_wait(file, &fc->waitq, wait);
1835
d7133114 1836 spin_lock(&fc->lock);
7025d9ad
MS
1837 if (!fc->connected)
1838 mask = POLLERR;
a4d27e75 1839 else if (request_pending(fc))
7025d9ad 1840 mask |= POLLIN | POLLRDNORM;
d7133114 1841 spin_unlock(&fc->lock);
334f485d
MS
1842
1843 return mask;
1844}
1845
69a53bf2
MS
1846/*
1847 * Abort all requests on the given list (pending or processing)
1848 *
d7133114 1849 * This function releases and reacquires fc->lock
69a53bf2 1850 */
334f485d 1851static void end_requests(struct fuse_conn *fc, struct list_head *head)
b9ca67b2
MS
1852__releases(fc->lock)
1853__acquires(fc->lock)
334f485d
MS
1854{
1855 while (!list_empty(head)) {
1856 struct fuse_req *req;
1857 req = list_entry(head->next, struct fuse_req, list);
334f485d
MS
1858 req->out.h.error = -ECONNABORTED;
1859 request_end(fc, req);
d7133114 1860 spin_lock(&fc->lock);
334f485d
MS
1861 }
1862}
1863
69a53bf2
MS
1864/*
1865 * Abort requests under I/O
1866 *
f9a2842e 1867 * The requests are set to aborted and finished, and the request
69a53bf2
MS
1868 * waiter is woken up. This will make request_wait_answer() wait
1869 * until the request is unlocked and then return.
64c6d8ed
MS
1870 *
1871 * If the request is asynchronous, then the end function needs to be
1872 * called after waiting for the request to be unlocked (if it was
1873 * locked).
69a53bf2
MS
1874 */
1875static void end_io_requests(struct fuse_conn *fc)
b9ca67b2
MS
1876__releases(fc->lock)
1877__acquires(fc->lock)
69a53bf2
MS
1878{
1879 while (!list_empty(&fc->io)) {
64c6d8ed
MS
1880 struct fuse_req *req =
1881 list_entry(fc->io.next, struct fuse_req, list);
1882 void (*end) (struct fuse_conn *, struct fuse_req *) = req->end;
1883
f9a2842e 1884 req->aborted = 1;
69a53bf2
MS
1885 req->out.h.error = -ECONNABORTED;
1886 req->state = FUSE_REQ_FINISHED;
1887 list_del_init(&req->list);
1888 wake_up(&req->waitq);
64c6d8ed
MS
1889 if (end) {
1890 req->end = NULL;
64c6d8ed 1891 __fuse_get_request(req);
d7133114 1892 spin_unlock(&fc->lock);
64c6d8ed
MS
1893 wait_event(req->waitq, !req->locked);
1894 end(fc, req);
e9bb09dd 1895 fuse_put_request(fc, req);
d7133114 1896 spin_lock(&fc->lock);
64c6d8ed 1897 }
69a53bf2
MS
1898 }
1899}
1900
595afaf9 1901static void end_queued_requests(struct fuse_conn *fc)
b9ca67b2
MS
1902__releases(fc->lock)
1903__acquires(fc->lock)
595afaf9
MS
1904{
1905 fc->max_background = UINT_MAX;
1906 flush_bg_queue(fc);
1907 end_requests(fc, &fc->pending);
1908 end_requests(fc, &fc->processing);
07e77dca 1909 while (forget_pending(fc))
02c048b9 1910 kfree(dequeue_forget(fc, 1, NULL));
595afaf9
MS
1911}
1912
357ccf2b
BG
1913static void end_polls(struct fuse_conn *fc)
1914{
1915 struct rb_node *p;
1916
1917 p = rb_first(&fc->polled_files);
1918
1919 while (p) {
1920 struct fuse_file *ff;
1921 ff = rb_entry(p, struct fuse_file, polled_node);
1922 wake_up_interruptible_all(&ff->poll_wait);
1923
1924 p = rb_next(p);
1925 }
1926}
1927
69a53bf2
MS
1928/*
1929 * Abort all requests.
1930 *
1931 * Emergency exit in case of a malicious or accidental deadlock, or
1932 * just a hung filesystem.
1933 *
1934 * The same effect is usually achievable through killing the
1935 * filesystem daemon and all users of the filesystem. The exception
1936 * is the combination of an asynchronous request and the tricky
1937 * deadlock (see Documentation/filesystems/fuse.txt).
1938 *
1939 * During the aborting, progression of requests from the pending and
1940 * processing lists onto the io list, and progression of new requests
1941 * onto the pending list is prevented by req->connected being false.
1942 *
1943 * Progression of requests under I/O to the processing list is
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1944 * prevented by the req->aborted flag being true for these requests.
1945 * For this reason requests on the io list must be aborted first.
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1946 */
1947void fuse_abort_conn(struct fuse_conn *fc)
1948{
d7133114 1949 spin_lock(&fc->lock);
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1950 if (fc->connected) {
1951 fc->connected = 0;
51eb01e7 1952 fc->blocked = 0;
69a53bf2 1953 end_io_requests(fc);
595afaf9 1954 end_queued_requests(fc);
357ccf2b 1955 end_polls(fc);
69a53bf2 1956 wake_up_all(&fc->waitq);
51eb01e7 1957 wake_up_all(&fc->blocked_waitq);
385a17bf 1958 kill_fasync(&fc->fasync, SIGIO, POLL_IN);
69a53bf2 1959 }
d7133114 1960 spin_unlock(&fc->lock);
69a53bf2 1961}
08cbf542 1962EXPORT_SYMBOL_GPL(fuse_abort_conn);
69a53bf2 1963
08cbf542 1964int fuse_dev_release(struct inode *inode, struct file *file)
334f485d 1965{
0720b315 1966 struct fuse_conn *fc = fuse_get_conn(file);
334f485d 1967 if (fc) {
d7133114 1968 spin_lock(&fc->lock);
1e9a4ed9 1969 fc->connected = 0;
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1970 fc->blocked = 0;
1971 end_queued_requests(fc);
357ccf2b 1972 end_polls(fc);
595afaf9 1973 wake_up_all(&fc->blocked_waitq);
d7133114 1974 spin_unlock(&fc->lock);
bafa9654 1975 fuse_conn_put(fc);
385a17bf 1976 }
f543f253 1977
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1978 return 0;
1979}
08cbf542 1980EXPORT_SYMBOL_GPL(fuse_dev_release);
334f485d 1981
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1982static int fuse_dev_fasync(int fd, struct file *file, int on)
1983{
1984 struct fuse_conn *fc = fuse_get_conn(file);
1985 if (!fc)
a87046d8 1986 return -EPERM;
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1987
1988 /* No locking - fasync_helper does its own locking */
1989 return fasync_helper(fd, file, on, &fc->fasync);
1990}
1991
4b6f5d20 1992const struct file_operations fuse_dev_operations = {
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1993 .owner = THIS_MODULE,
1994 .llseek = no_llseek,
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1995 .read = do_sync_read,
1996 .aio_read = fuse_dev_read,
c3021629 1997 .splice_read = fuse_dev_splice_read,
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1998 .write = do_sync_write,
1999 .aio_write = fuse_dev_write,
dd3bb14f 2000 .splice_write = fuse_dev_splice_write,
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2001 .poll = fuse_dev_poll,
2002 .release = fuse_dev_release,
385a17bf 2003 .fasync = fuse_dev_fasync,
334f485d 2004};
08cbf542 2005EXPORT_SYMBOL_GPL(fuse_dev_operations);
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2006
2007static struct miscdevice fuse_miscdevice = {
2008 .minor = FUSE_MINOR,
2009 .name = "fuse",
2010 .fops = &fuse_dev_operations,
2011};
2012
2013int __init fuse_dev_init(void)
2014{
2015 int err = -ENOMEM;
2016 fuse_req_cachep = kmem_cache_create("fuse_request",
2017 sizeof(struct fuse_req),
20c2df83 2018 0, 0, NULL);
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2019 if (!fuse_req_cachep)
2020 goto out;
2021
2022 err = misc_register(&fuse_miscdevice);
2023 if (err)
2024 goto out_cache_clean;
2025
2026 return 0;
2027
2028 out_cache_clean:
2029 kmem_cache_destroy(fuse_req_cachep);
2030 out:
2031 return err;
2032}
2033
2034void fuse_dev_cleanup(void)
2035{
2036 misc_deregister(&fuse_miscdevice);
2037 kmem_cache_destroy(fuse_req_cachep);
2038}