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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>
19
20MODULE_ALIAS_MISCDEV(FUSE_MINOR);
21
22static struct kmem_cache *fuse_req_cachep;
23
24static struct fuse_conn *fuse_get_conn(struct file *file)
25{
26
27
28
29
30 return file->private_data;
31}
32
33static void fuse_request_init(struct fuse_req *req)
34{
35 memset(req, 0, sizeof(*req));
36 INIT_LIST_HEAD(&req->list);
37 INIT_LIST_HEAD(&req->intr_entry);
38 init_waitqueue_head(&req->waitq);
39 atomic_set(&req->count, 1);
40}
41
42struct fuse_req *fuse_request_alloc(void)
43{
44 struct fuse_req *req = kmem_cache_alloc(fuse_req_cachep, GFP_KERNEL);
45 if (req)
46 fuse_request_init(req);
47 return req;
48}
49
50struct fuse_req *fuse_request_alloc_nofs(void)
51{
52 struct fuse_req *req = kmem_cache_alloc(fuse_req_cachep, GFP_NOFS);
53 if (req)
54 fuse_request_init(req);
55 return req;
56}
57
58void fuse_request_free(struct fuse_req *req)
59{
60 kmem_cache_free(fuse_req_cachep, req);
61}
62
63static void block_sigs(sigset_t *oldset)
64{
65 sigset_t mask;
66
67 siginitsetinv(&mask, sigmask(SIGKILL));
68 sigprocmask(SIG_BLOCK, &mask, oldset);
69}
70
71static void restore_sigs(sigset_t *oldset)
72{
73 sigprocmask(SIG_SETMASK, oldset, NULL);
74}
75
76static void __fuse_get_request(struct fuse_req *req)
77{
78 atomic_inc(&req->count);
79}
80
81
82static void __fuse_put_request(struct fuse_req *req)
83{
84 BUG_ON(atomic_read(&req->count) < 2);
85 atomic_dec(&req->count);
86}
87
88static void fuse_req_init_context(struct fuse_req *req)
89{
90 req->in.h.uid = current->fsuid;
91 req->in.h.gid = current->fsgid;
92 req->in.h.pid = current->pid;
93}
94
95struct fuse_req *fuse_get_req(struct fuse_conn *fc)
96{
97 struct fuse_req *req;
98 sigset_t oldset;
99 int intr;
100 int err;
101
102 atomic_inc(&fc->num_waiting);
103 block_sigs(&oldset);
104 intr = wait_event_interruptible(fc->blocked_waitq, !fc->blocked);
105 restore_sigs(&oldset);
106 err = -EINTR;
107 if (intr)
108 goto out;
109
110 err = -ENOTCONN;
111 if (!fc->connected)
112 goto out;
113
114 req = fuse_request_alloc();
115 err = -ENOMEM;
116 if (!req)
117 goto out;
118
119 fuse_req_init_context(req);
120 req->waiting = 1;
121 return req;
122
123 out:
124 atomic_dec(&fc->num_waiting);
125 return ERR_PTR(err);
126}
127
128
129
130
131
132
133static struct fuse_req *get_reserved_req(struct fuse_conn *fc,
134 struct file *file)
135{
136 struct fuse_req *req = NULL;
137 struct fuse_file *ff = file->private_data;
138
139 do {
140 wait_event(fc->reserved_req_waitq, ff->reserved_req);
141 spin_lock(&fc->lock);
142 if (ff->reserved_req) {
143 req = ff->reserved_req;
144 ff->reserved_req = NULL;
145 get_file(file);
146 req->stolen_file = file;
147 }
148 spin_unlock(&fc->lock);
149 } while (!req);
150
151 return req;
152}
153
154
155
156
157static void put_reserved_req(struct fuse_conn *fc, struct fuse_req *req)
158{
159 struct file *file = req->stolen_file;
160 struct fuse_file *ff = file->private_data;
161
162 spin_lock(&fc->lock);
163 fuse_request_init(req);
164 BUG_ON(ff->reserved_req);
165 ff->reserved_req = req;
166 wake_up_all(&fc->reserved_req_waitq);
167 spin_unlock(&fc->lock);
168 fput(file);
169}
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184struct fuse_req *fuse_get_req_nofail(struct fuse_conn *fc, struct file *file)
185{
186 struct fuse_req *req;
187
188 atomic_inc(&fc->num_waiting);
189 wait_event(fc->blocked_waitq, !fc->blocked);
190 req = fuse_request_alloc();
191 if (!req)
192 req = get_reserved_req(fc, file);
193
194 fuse_req_init_context(req);
195 req->waiting = 1;
196 return req;
197}
198
199void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req)
200{
201 if (atomic_dec_and_test(&req->count)) {
202 if (req->waiting)
203 atomic_dec(&fc->num_waiting);
204
205 if (req->stolen_file)
206 put_reserved_req(fc, req);
207 else
208 fuse_request_free(req);
209 }
210}
211
212static unsigned len_args(unsigned numargs, struct fuse_arg *args)
213{
214 unsigned nbytes = 0;
215 unsigned i;
216
217 for (i = 0; i < numargs; i++)
218 nbytes += args[i].size;
219
220 return nbytes;
221}
222
223static u64 fuse_get_unique(struct fuse_conn *fc)
224{
225 fc->reqctr++;
226
227 if (fc->reqctr == 0)
228 fc->reqctr = 1;
229
230 return fc->reqctr;
231}
232
233static void queue_request(struct fuse_conn *fc, struct fuse_req *req)
234{
235 req->in.h.unique = fuse_get_unique(fc);
236 req->in.h.len = sizeof(struct fuse_in_header) +
237 len_args(req->in.numargs, (struct fuse_arg *) req->in.args);
238 list_add_tail(&req->list, &fc->pending);
239 req->state = FUSE_REQ_PENDING;
240 if (!req->waiting) {
241 req->waiting = 1;
242 atomic_inc(&fc->num_waiting);
243 }
244 wake_up(&fc->waitq);
245 kill_fasync(&fc->fasync, SIGIO, POLL_IN);
246}
247
248static void flush_bg_queue(struct fuse_conn *fc)
249{
250 while (fc->active_background < FUSE_MAX_BACKGROUND &&
251 !list_empty(&fc->bg_queue)) {
252 struct fuse_req *req;
253
254 req = list_entry(fc->bg_queue.next, struct fuse_req, list);
255 list_del(&req->list);
256 fc->active_background++;
257 queue_request(fc, req);
258 }
259}
260
261
262
263
264
265
266
267
268
269
270
271static void request_end(struct fuse_conn *fc, struct fuse_req *req)
272 __releases(fc->lock)
273{
274 void (*end) (struct fuse_conn *, struct fuse_req *) = req->end;
275 req->end = NULL;
276 list_del(&req->list);
277 list_del(&req->intr_entry);
278 req->state = FUSE_REQ_FINISHED;
279 if (req->background) {
280 if (fc->num_background == FUSE_MAX_BACKGROUND) {
281 fc->blocked = 0;
282 wake_up_all(&fc->blocked_waitq);
283 }
284 if (fc->num_background == FUSE_CONGESTION_THRESHOLD) {
285 clear_bdi_congested(&fc->bdi, READ);
286 clear_bdi_congested(&fc->bdi, WRITE);
287 }
288 fc->num_background--;
289 fc->active_background--;
290 flush_bg_queue(fc);
291 }
292 spin_unlock(&fc->lock);
293 wake_up(&req->waitq);
294 if (end)
295 end(fc, req);
296 else
297 fuse_put_request(fc, req);
298}
299
300static void wait_answer_interruptible(struct fuse_conn *fc,
301 struct fuse_req *req)
302 __releases(fc->lock) __acquires(fc->lock)
303{
304 if (signal_pending(current))
305 return;
306
307 spin_unlock(&fc->lock);
308 wait_event_interruptible(req->waitq, req->state == FUSE_REQ_FINISHED);
309 spin_lock(&fc->lock);
310}
311
312static void queue_interrupt(struct fuse_conn *fc, struct fuse_req *req)
313{
314 list_add_tail(&req->intr_entry, &fc->interrupts);
315 wake_up(&fc->waitq);
316 kill_fasync(&fc->fasync, SIGIO, POLL_IN);
317}
318
319static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
320 __releases(fc->lock) __acquires(fc->lock)
321{
322 if (!fc->no_interrupt) {
323
324 wait_answer_interruptible(fc, req);
325
326 if (req->aborted)
327 goto aborted;
328 if (req->state == FUSE_REQ_FINISHED)
329 return;
330
331 req->interrupted = 1;
332 if (req->state == FUSE_REQ_SENT)
333 queue_interrupt(fc, req);
334 }
335
336 if (!req->force) {
337 sigset_t oldset;
338
339
340 block_sigs(&oldset);
341 wait_answer_interruptible(fc, req);
342 restore_sigs(&oldset);
343
344 if (req->aborted)
345 goto aborted;
346 if (req->state == FUSE_REQ_FINISHED)
347 return;
348
349
350 if (req->state == FUSE_REQ_PENDING) {
351 list_del(&req->list);
352 __fuse_put_request(req);
353 req->out.h.error = -EINTR;
354 return;
355 }
356 }
357
358
359
360
361
362 spin_unlock(&fc->lock);
363 wait_event(req->waitq, req->state == FUSE_REQ_FINISHED);
364 spin_lock(&fc->lock);
365
366 if (!req->aborted)
367 return;
368
369 aborted:
370 BUG_ON(req->state != FUSE_REQ_FINISHED);
371 if (req->locked) {
372
373
374
375
376
377 spin_unlock(&fc->lock);
378 wait_event(req->waitq, !req->locked);
379 spin_lock(&fc->lock);
380 }
381}
382
383void request_send(struct fuse_conn *fc, struct fuse_req *req)
384{
385 req->isreply = 1;
386 spin_lock(&fc->lock);
387 if (!fc->connected)
388 req->out.h.error = -ENOTCONN;
389 else if (fc->conn_error)
390 req->out.h.error = -ECONNREFUSED;
391 else {
392 queue_request(fc, req);
393
394
395 __fuse_get_request(req);
396
397 request_wait_answer(fc, req);
398 }
399 spin_unlock(&fc->lock);
400}
401
402static void request_send_nowait_locked(struct fuse_conn *fc,
403 struct fuse_req *req)
404{
405 req->background = 1;
406 fc->num_background++;
407 if (fc->num_background == FUSE_MAX_BACKGROUND)
408 fc->blocked = 1;
409 if (fc->num_background == FUSE_CONGESTION_THRESHOLD) {
410 set_bdi_congested(&fc->bdi, READ);
411 set_bdi_congested(&fc->bdi, WRITE);
412 }
413 list_add_tail(&req->list, &fc->bg_queue);
414 flush_bg_queue(fc);
415}
416
417static void request_send_nowait(struct fuse_conn *fc, struct fuse_req *req)
418{
419 spin_lock(&fc->lock);
420 if (fc->connected) {
421 request_send_nowait_locked(fc, req);
422 spin_unlock(&fc->lock);
423 } else {
424 req->out.h.error = -ENOTCONN;
425 request_end(fc, req);
426 }
427}
428
429void request_send_noreply(struct fuse_conn *fc, struct fuse_req *req)
430{
431 req->isreply = 0;
432 request_send_nowait(fc, req);
433}
434
435void request_send_background(struct fuse_conn *fc, struct fuse_req *req)
436{
437 req->isreply = 1;
438 request_send_nowait(fc, req);
439}
440
441
442
443
444
445
446void request_send_background_locked(struct fuse_conn *fc, struct fuse_req *req)
447{
448 req->isreply = 1;
449 request_send_nowait_locked(fc, req);
450}
451
452
453
454
455
456
457static int lock_request(struct fuse_conn *fc, struct fuse_req *req)
458{
459 int err = 0;
460 if (req) {
461 spin_lock(&fc->lock);
462 if (req->aborted)
463 err = -ENOENT;
464 else
465 req->locked = 1;
466 spin_unlock(&fc->lock);
467 }
468 return err;
469}
470
471
472
473
474
475
476static void unlock_request(struct fuse_conn *fc, struct fuse_req *req)
477{
478 if (req) {
479 spin_lock(&fc->lock);
480 req->locked = 0;
481 if (req->aborted)
482 wake_up(&req->waitq);
483 spin_unlock(&fc->lock);
484 }
485}
486
487struct fuse_copy_state {
488 struct fuse_conn *fc;
489 int write;
490 struct fuse_req *req;
491 const struct iovec *iov;
492 unsigned long nr_segs;
493 unsigned long seglen;
494 unsigned long addr;
495 struct page *pg;
496 void *mapaddr;
497 void *buf;
498 unsigned len;
499};
500
501static void fuse_copy_init(struct fuse_copy_state *cs, struct fuse_conn *fc,
502 int write, struct fuse_req *req,
503 const struct iovec *iov, unsigned long nr_segs)
504{
505 memset(cs, 0, sizeof(*cs));
506 cs->fc = fc;
507 cs->write = write;
508 cs->req = req;
509 cs->iov = iov;
510 cs->nr_segs = nr_segs;
511}
512
513
514static void fuse_copy_finish(struct fuse_copy_state *cs)
515{
516 if (cs->mapaddr) {
517 kunmap_atomic(cs->mapaddr, KM_USER0);
518 if (cs->write) {
519 flush_dcache_page(cs->pg);
520 set_page_dirty_lock(cs->pg);
521 }
522 put_page(cs->pg);
523 cs->mapaddr = NULL;
524 }
525}
526
527
528
529
530
531static int fuse_copy_fill(struct fuse_copy_state *cs)
532{
533 unsigned long offset;
534 int err;
535
536 unlock_request(cs->fc, cs->req);
537 fuse_copy_finish(cs);
538 if (!cs->seglen) {
539 BUG_ON(!cs->nr_segs);
540 cs->seglen = cs->iov[0].iov_len;
541 cs->addr = (unsigned long) cs->iov[0].iov_base;
542 cs->iov ++;
543 cs->nr_segs --;
544 }
545 down_read(¤t->mm->mmap_sem);
546 err = get_user_pages(current, current->mm, cs->addr, 1, cs->write, 0,
547 &cs->pg, NULL);
548 up_read(¤t->mm->mmap_sem);
549 if (err < 0)
550 return err;
551 BUG_ON(err != 1);
552 offset = cs->addr % PAGE_SIZE;
553 cs->mapaddr = kmap_atomic(cs->pg, KM_USER0);
554 cs->buf = cs->mapaddr + offset;
555 cs->len = min(PAGE_SIZE - offset, cs->seglen);
556 cs->seglen -= cs->len;
557 cs->addr += cs->len;
558
559 return lock_request(cs->fc, cs->req);
560}
561
562
563static int fuse_copy_do(struct fuse_copy_state *cs, void **val, unsigned *size)
564{
565 unsigned ncpy = min(*size, cs->len);
566 if (val) {
567 if (cs->write)
568 memcpy(cs->buf, *val, ncpy);
569 else
570 memcpy(*val, cs->buf, ncpy);
571 *val += ncpy;
572 }
573 *size -= ncpy;
574 cs->len -= ncpy;
575 cs->buf += ncpy;
576 return ncpy;
577}
578
579
580
581
582
583static int fuse_copy_page(struct fuse_copy_state *cs, struct page *page,
584 unsigned offset, unsigned count, int zeroing)
585{
586 if (page && zeroing && count < PAGE_SIZE) {
587 void *mapaddr = kmap_atomic(page, KM_USER1);
588 memset(mapaddr, 0, PAGE_SIZE);
589 kunmap_atomic(mapaddr, KM_USER1);
590 }
591 while (count) {
592 int err;
593 if (!cs->len && (err = fuse_copy_fill(cs)))
594 return err;
595 if (page) {
596 void *mapaddr = kmap_atomic(page, KM_USER1);
597 void *buf = mapaddr + offset;
598 offset += fuse_copy_do(cs, &buf, &count);
599 kunmap_atomic(mapaddr, KM_USER1);
600 } else
601 offset += fuse_copy_do(cs, NULL, &count);
602 }
603 if (page && !cs->write)
604 flush_dcache_page(page);
605 return 0;
606}
607
608
609static int fuse_copy_pages(struct fuse_copy_state *cs, unsigned nbytes,
610 int zeroing)
611{
612 unsigned i;
613 struct fuse_req *req = cs->req;
614 unsigned offset = req->page_offset;
615 unsigned count = min(nbytes, (unsigned) PAGE_SIZE - offset);
616
617 for (i = 0; i < req->num_pages && (nbytes || zeroing); i++) {
618 struct page *page = req->pages[i];
619 int err = fuse_copy_page(cs, page, offset, count, zeroing);
620 if (err)
621 return err;
622
623 nbytes -= count;
624 count = min(nbytes, (unsigned) PAGE_SIZE);
625 offset = 0;
626 }
627 return 0;
628}
629
630
631static int fuse_copy_one(struct fuse_copy_state *cs, void *val, unsigned size)
632{
633 while (size) {
634 int err;
635 if (!cs->len && (err = fuse_copy_fill(cs)))
636 return err;
637 fuse_copy_do(cs, &val, &size);
638 }
639 return 0;
640}
641
642
643static int fuse_copy_args(struct fuse_copy_state *cs, unsigned numargs,
644 unsigned argpages, struct fuse_arg *args,
645 int zeroing)
646{
647 int err = 0;
648 unsigned i;
649
650 for (i = 0; !err && i < numargs; i++) {
651 struct fuse_arg *arg = &args[i];
652 if (i == numargs - 1 && argpages)
653 err = fuse_copy_pages(cs, arg->size, zeroing);
654 else
655 err = fuse_copy_one(cs, arg->value, arg->size);
656 }
657 return err;
658}
659
660static int request_pending(struct fuse_conn *fc)
661{
662 return !list_empty(&fc->pending) || !list_empty(&fc->interrupts);
663}
664
665
666static void request_wait(struct fuse_conn *fc)
667{
668 DECLARE_WAITQUEUE(wait, current);
669
670 add_wait_queue_exclusive(&fc->waitq, &wait);
671 while (fc->connected && !request_pending(fc)) {
672 set_current_state(TASK_INTERRUPTIBLE);
673 if (signal_pending(current))
674 break;
675
676 spin_unlock(&fc->lock);
677 schedule();
678 spin_lock(&fc->lock);
679 }
680 set_current_state(TASK_RUNNING);
681 remove_wait_queue(&fc->waitq, &wait);
682}
683
684
685
686
687
688
689
690
691
692static int fuse_read_interrupt(struct fuse_conn *fc, struct fuse_req *req,
693 const struct iovec *iov, unsigned long nr_segs)
694 __releases(fc->lock)
695{
696 struct fuse_copy_state cs;
697 struct fuse_in_header ih;
698 struct fuse_interrupt_in arg;
699 unsigned reqsize = sizeof(ih) + sizeof(arg);
700 int err;
701
702 list_del_init(&req->intr_entry);
703 req->intr_unique = fuse_get_unique(fc);
704 memset(&ih, 0, sizeof(ih));
705 memset(&arg, 0, sizeof(arg));
706 ih.len = reqsize;
707 ih.opcode = FUSE_INTERRUPT;
708 ih.unique = req->intr_unique;
709 arg.unique = req->in.h.unique;
710
711 spin_unlock(&fc->lock);
712 if (iov_length(iov, nr_segs) < reqsize)
713 return -EINVAL;
714
715 fuse_copy_init(&cs, fc, 1, NULL, iov, nr_segs);
716 err = fuse_copy_one(&cs, &ih, sizeof(ih));
717 if (!err)
718 err = fuse_copy_one(&cs, &arg, sizeof(arg));
719 fuse_copy_finish(&cs);
720
721 return err ? err : reqsize;
722}
723
724
725
726
727
728
729
730
731
732
733static ssize_t fuse_dev_read(struct kiocb *iocb, const struct iovec *iov,
734 unsigned long nr_segs, loff_t pos)
735{
736 int err;
737 struct fuse_req *req;
738 struct fuse_in *in;
739 struct fuse_copy_state cs;
740 unsigned reqsize;
741 struct file *file = iocb->ki_filp;
742 struct fuse_conn *fc = fuse_get_conn(file);
743 if (!fc)
744 return -EPERM;
745
746 restart:
747 spin_lock(&fc->lock);
748 err = -EAGAIN;
749 if ((file->f_flags & O_NONBLOCK) && fc->connected &&
750 !request_pending(fc))
751 goto err_unlock;
752
753 request_wait(fc);
754 err = -ENODEV;
755 if (!fc->connected)
756 goto err_unlock;
757 err = -ERESTARTSYS;
758 if (!request_pending(fc))
759 goto err_unlock;
760
761 if (!list_empty(&fc->interrupts)) {
762 req = list_entry(fc->interrupts.next, struct fuse_req,
763 intr_entry);
764 return fuse_read_interrupt(fc, req, iov, nr_segs);
765 }
766
767 req = list_entry(fc->pending.next, struct fuse_req, list);
768 req->state = FUSE_REQ_READING;
769 list_move(&req->list, &fc->io);
770
771 in = &req->in;
772 reqsize = in->h.len;
773
774 if (iov_length(iov, nr_segs) < reqsize) {
775 req->out.h.error = -EIO;
776
777 if (in->h.opcode == FUSE_SETXATTR)
778 req->out.h.error = -E2BIG;
779 request_end(fc, req);
780 goto restart;
781 }
782 spin_unlock(&fc->lock);
783 fuse_copy_init(&cs, fc, 1, req, iov, nr_segs);
784 err = fuse_copy_one(&cs, &in->h, sizeof(in->h));
785 if (!err)
786 err = fuse_copy_args(&cs, in->numargs, in->argpages,
787 (struct fuse_arg *) in->args, 0);
788 fuse_copy_finish(&cs);
789 spin_lock(&fc->lock);
790 req->locked = 0;
791 if (req->aborted) {
792 request_end(fc, req);
793 return -ENODEV;
794 }
795 if (err) {
796 req->out.h.error = -EIO;
797 request_end(fc, req);
798 return err;
799 }
800 if (!req->isreply)
801 request_end(fc, req);
802 else {
803 req->state = FUSE_REQ_SENT;
804 list_move_tail(&req->list, &fc->processing);
805 if (req->interrupted)
806 queue_interrupt(fc, req);
807 spin_unlock(&fc->lock);
808 }
809 return reqsize;
810
811 err_unlock:
812 spin_unlock(&fc->lock);
813 return err;
814}
815
816
817static struct fuse_req *request_find(struct fuse_conn *fc, u64 unique)
818{
819 struct list_head *entry;
820
821 list_for_each(entry, &fc->processing) {
822 struct fuse_req *req;
823 req = list_entry(entry, struct fuse_req, list);
824 if (req->in.h.unique == unique || req->intr_unique == unique)
825 return req;
826 }
827 return NULL;
828}
829
830static int copy_out_args(struct fuse_copy_state *cs, struct fuse_out *out,
831 unsigned nbytes)
832{
833 unsigned reqsize = sizeof(struct fuse_out_header);
834
835 if (out->h.error)
836 return nbytes != reqsize ? -EINVAL : 0;
837
838 reqsize += len_args(out->numargs, out->args);
839
840 if (reqsize < nbytes || (reqsize > nbytes && !out->argvar))
841 return -EINVAL;
842 else if (reqsize > nbytes) {
843 struct fuse_arg *lastarg = &out->args[out->numargs-1];
844 unsigned diffsize = reqsize - nbytes;
845 if (diffsize > lastarg->size)
846 return -EINVAL;
847 lastarg->size -= diffsize;
848 }
849 return fuse_copy_args(cs, out->numargs, out->argpages, out->args,
850 out->page_zeroing);
851}
852
853
854
855
856
857
858
859
860static ssize_t fuse_dev_write(struct kiocb *iocb, const struct iovec *iov,
861 unsigned long nr_segs, loff_t pos)
862{
863 int err;
864 unsigned nbytes = iov_length(iov, nr_segs);
865 struct fuse_req *req;
866 struct fuse_out_header oh;
867 struct fuse_copy_state cs;
868 struct fuse_conn *fc = fuse_get_conn(iocb->ki_filp);
869 if (!fc)
870 return -EPERM;
871
872 fuse_copy_init(&cs, fc, 0, NULL, iov, nr_segs);
873 if (nbytes < sizeof(struct fuse_out_header))
874 return -EINVAL;
875
876 err = fuse_copy_one(&cs, &oh, sizeof(oh));
877 if (err)
878 goto err_finish;
879 err = -EINVAL;
880 if (!oh.unique || oh.error <= -1000 || oh.error > 0 ||
881 oh.len != nbytes)
882 goto err_finish;
883
884 spin_lock(&fc->lock);
885 err = -ENOENT;
886 if (!fc->connected)
887 goto err_unlock;
888
889 req = request_find(fc, oh.unique);
890 if (!req)
891 goto err_unlock;
892
893 if (req->aborted) {
894 spin_unlock(&fc->lock);
895 fuse_copy_finish(&cs);
896 spin_lock(&fc->lock);
897 request_end(fc, req);
898 return -ENOENT;
899 }
900
901 if (req->intr_unique == oh.unique) {
902 err = -EINVAL;
903 if (nbytes != sizeof(struct fuse_out_header))
904 goto err_unlock;
905
906 if (oh.error == -ENOSYS)
907 fc->no_interrupt = 1;
908 else if (oh.error == -EAGAIN)
909 queue_interrupt(fc, req);
910
911 spin_unlock(&fc->lock);
912 fuse_copy_finish(&cs);
913 return nbytes;
914 }
915
916 req->state = FUSE_REQ_WRITING;
917 list_move(&req->list, &fc->io);
918 req->out.h = oh;
919 req->locked = 1;
920 cs.req = req;
921 spin_unlock(&fc->lock);
922
923 err = copy_out_args(&cs, &req->out, nbytes);
924 fuse_copy_finish(&cs);
925
926 spin_lock(&fc->lock);
927 req->locked = 0;
928 if (!err) {
929 if (req->aborted)
930 err = -ENOENT;
931 } else if (!req->aborted)
932 req->out.h.error = -EIO;
933 request_end(fc, req);
934
935 return err ? err : nbytes;
936
937 err_unlock:
938 spin_unlock(&fc->lock);
939 err_finish:
940 fuse_copy_finish(&cs);
941 return err;
942}
943
944static unsigned fuse_dev_poll(struct file *file, poll_table *wait)
945{
946 unsigned mask = POLLOUT | POLLWRNORM;
947 struct fuse_conn *fc = fuse_get_conn(file);
948 if (!fc)
949 return POLLERR;
950
951 poll_wait(file, &fc->waitq, wait);
952
953 spin_lock(&fc->lock);
954 if (!fc->connected)
955 mask = POLLERR;
956 else if (request_pending(fc))
957 mask |= POLLIN | POLLRDNORM;
958 spin_unlock(&fc->lock);
959
960 return mask;
961}
962
963
964
965
966
967
968static void end_requests(struct fuse_conn *fc, struct list_head *head)
969{
970 while (!list_empty(head)) {
971 struct fuse_req *req;
972 req = list_entry(head->next, struct fuse_req, list);
973 req->out.h.error = -ECONNABORTED;
974 request_end(fc, req);
975 spin_lock(&fc->lock);
976 }
977}
978
979
980
981
982
983
984
985
986
987
988
989
990static void end_io_requests(struct fuse_conn *fc)
991 __releases(fc->lock) __acquires(fc->lock)
992{
993 while (!list_empty(&fc->io)) {
994 struct fuse_req *req =
995 list_entry(fc->io.next, struct fuse_req, list);
996 void (*end) (struct fuse_conn *, struct fuse_req *) = req->end;
997
998 req->aborted = 1;
999 req->out.h.error = -ECONNABORTED;
1000 req->state = FUSE_REQ_FINISHED;
1001 list_del_init(&req->list);
1002 wake_up(&req->waitq);
1003 if (end) {
1004 req->end = NULL;
1005
1006 __fuse_get_request(req);
1007 spin_unlock(&fc->lock);
1008 wait_event(req->waitq, !req->locked);
1009 end(fc, req);
1010 spin_lock(&fc->lock);
1011 }
1012 }
1013}
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034void fuse_abort_conn(struct fuse_conn *fc)
1035{
1036 spin_lock(&fc->lock);
1037 if (fc->connected) {
1038 fc->connected = 0;
1039 fc->blocked = 0;
1040 end_io_requests(fc);
1041 end_requests(fc, &fc->pending);
1042 end_requests(fc, &fc->processing);
1043 wake_up_all(&fc->waitq);
1044 wake_up_all(&fc->blocked_waitq);
1045 kill_fasync(&fc->fasync, SIGIO, POLL_IN);
1046 }
1047 spin_unlock(&fc->lock);
1048}
1049
1050static int fuse_dev_release(struct inode *inode, struct file *file)
1051{
1052 struct fuse_conn *fc = fuse_get_conn(file);
1053 if (fc) {
1054 spin_lock(&fc->lock);
1055 fc->connected = 0;
1056 end_requests(fc, &fc->pending);
1057 end_requests(fc, &fc->processing);
1058 spin_unlock(&fc->lock);
1059 fuse_conn_put(fc);
1060 }
1061
1062 return 0;
1063}
1064
1065static int fuse_dev_fasync(int fd, struct file *file, int on)
1066{
1067 struct fuse_conn *fc = fuse_get_conn(file);
1068 if (!fc)
1069 return -EPERM;
1070
1071
1072 return fasync_helper(fd, file, on, &fc->fasync);
1073}
1074
1075const struct file_operations fuse_dev_operations = {
1076 .owner = THIS_MODULE,
1077 .llseek = no_llseek,
1078 .read = do_sync_read,
1079 .aio_read = fuse_dev_read,
1080 .write = do_sync_write,
1081 .aio_write = fuse_dev_write,
1082 .poll = fuse_dev_poll,
1083 .release = fuse_dev_release,
1084 .fasync = fuse_dev_fasync,
1085};
1086
1087static struct miscdevice fuse_miscdevice = {
1088 .minor = FUSE_MINOR,
1089 .name = "fuse",
1090 .fops = &fuse_dev_operations,
1091};
1092
1093int __init fuse_dev_init(void)
1094{
1095 int err = -ENOMEM;
1096 fuse_req_cachep = kmem_cache_create("fuse_request",
1097 sizeof(struct fuse_req),
1098 0, 0, NULL);
1099 if (!fuse_req_cachep)
1100 goto out;
1101
1102 err = misc_register(&fuse_miscdevice);
1103 if (err)
1104 goto out_cache_clean;
1105
1106 return 0;
1107
1108 out_cache_clean:
1109 kmem_cache_destroy(fuse_req_cachep);
1110 out:
1111 return err;
1112}
1113
1114void fuse_dev_cleanup(void)
1115{
1116 misc_deregister(&fuse_miscdevice);
1117 kmem_cache_destroy(fuse_req_cachep);
1118}