2 FUSE: Filesystem in Userspace
3 Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu>
5 This program can be distributed under the terms of the GNU GPL.
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 #include <linux/pipe_fs_i.h>
20 #include <linux/swap.h>
21 #include <linux/splice.h>
23 MODULE_ALIAS_MISCDEV(FUSE_MINOR
);
24 MODULE_ALIAS("devname:fuse");
26 static struct kmem_cache
*fuse_req_cachep
;
28 static struct fuse_conn
*fuse_get_conn(struct file
*file
)
31 * Lockless access is OK, because file->private data is set
32 * once during mount and is valid until the file is released.
34 return file
->private_data
;
37 static void fuse_request_init(struct fuse_req
*req
, struct page
**pages
,
38 struct fuse_page_desc
*page_descs
,
41 memset(req
, 0, sizeof(*req
));
42 memset(pages
, 0, sizeof(*pages
) * npages
);
43 memset(page_descs
, 0, sizeof(*page_descs
) * npages
);
44 INIT_LIST_HEAD(&req
->list
);
45 INIT_LIST_HEAD(&req
->intr_entry
);
46 init_waitqueue_head(&req
->waitq
);
47 atomic_set(&req
->count
, 1);
49 req
->page_descs
= page_descs
;
50 req
->max_pages
= npages
;
51 __set_bit(FR_PENDING
, &req
->flags
);
54 static struct fuse_req
*__fuse_request_alloc(unsigned npages
, gfp_t flags
)
56 struct fuse_req
*req
= kmem_cache_alloc(fuse_req_cachep
, flags
);
59 struct fuse_page_desc
*page_descs
;
61 if (npages
<= FUSE_REQ_INLINE_PAGES
) {
62 pages
= req
->inline_pages
;
63 page_descs
= req
->inline_page_descs
;
65 pages
= kmalloc(sizeof(struct page
*) * npages
, flags
);
66 page_descs
= kmalloc(sizeof(struct fuse_page_desc
) *
70 if (!pages
|| !page_descs
) {
73 kmem_cache_free(fuse_req_cachep
, req
);
77 fuse_request_init(req
, pages
, page_descs
, npages
);
82 struct fuse_req
*fuse_request_alloc(unsigned npages
)
84 return __fuse_request_alloc(npages
, GFP_KERNEL
);
86 EXPORT_SYMBOL_GPL(fuse_request_alloc
);
88 struct fuse_req
*fuse_request_alloc_nofs(unsigned npages
)
90 return __fuse_request_alloc(npages
, GFP_NOFS
);
93 void fuse_request_free(struct fuse_req
*req
)
95 if (req
->pages
!= req
->inline_pages
) {
97 kfree(req
->page_descs
);
99 kmem_cache_free(fuse_req_cachep
, req
);
102 static void block_sigs(sigset_t
*oldset
)
106 siginitsetinv(&mask
, sigmask(SIGKILL
));
107 sigprocmask(SIG_BLOCK
, &mask
, oldset
);
110 static void restore_sigs(sigset_t
*oldset
)
112 sigprocmask(SIG_SETMASK
, oldset
, NULL
);
115 void __fuse_get_request(struct fuse_req
*req
)
117 atomic_inc(&req
->count
);
120 /* Must be called with > 1 refcount */
121 static void __fuse_put_request(struct fuse_req
*req
)
123 BUG_ON(atomic_read(&req
->count
) < 2);
124 atomic_dec(&req
->count
);
127 static void fuse_req_init_context(struct fuse_req
*req
)
129 req
->in
.h
.uid
= from_kuid_munged(&init_user_ns
, current_fsuid());
130 req
->in
.h
.gid
= from_kgid_munged(&init_user_ns
, current_fsgid());
131 req
->in
.h
.pid
= current
->pid
;
134 void fuse_set_initialized(struct fuse_conn
*fc
)
136 /* Make sure stores before this are seen on another CPU */
141 static bool fuse_block_alloc(struct fuse_conn
*fc
, bool for_background
)
143 return !fc
->initialized
|| (for_background
&& fc
->blocked
);
146 static struct fuse_req
*__fuse_get_req(struct fuse_conn
*fc
, unsigned npages
,
149 struct fuse_req
*req
;
151 atomic_inc(&fc
->num_waiting
);
153 if (fuse_block_alloc(fc
, for_background
)) {
158 intr
= wait_event_interruptible_exclusive(fc
->blocked_waitq
,
159 !fuse_block_alloc(fc
, for_background
));
160 restore_sigs(&oldset
);
165 /* Matches smp_wmb() in fuse_set_initialized() */
176 req
= fuse_request_alloc(npages
);
180 wake_up(&fc
->blocked_waitq
);
184 fuse_req_init_context(req
);
185 __set_bit(FR_WAITING
, &req
->flags
);
187 __set_bit(FR_BACKGROUND
, &req
->flags
);
192 atomic_dec(&fc
->num_waiting
);
196 struct fuse_req
*fuse_get_req(struct fuse_conn
*fc
, unsigned npages
)
198 return __fuse_get_req(fc
, npages
, false);
200 EXPORT_SYMBOL_GPL(fuse_get_req
);
202 struct fuse_req
*fuse_get_req_for_background(struct fuse_conn
*fc
,
205 return __fuse_get_req(fc
, npages
, true);
207 EXPORT_SYMBOL_GPL(fuse_get_req_for_background
);
210 * Return request in fuse_file->reserved_req. However that may
211 * currently be in use. If that is the case, wait for it to become
214 static struct fuse_req
*get_reserved_req(struct fuse_conn
*fc
,
217 struct fuse_req
*req
= NULL
;
218 struct fuse_file
*ff
= file
->private_data
;
221 wait_event(fc
->reserved_req_waitq
, ff
->reserved_req
);
222 spin_lock(&fc
->lock
);
223 if (ff
->reserved_req
) {
224 req
= ff
->reserved_req
;
225 ff
->reserved_req
= NULL
;
226 req
->stolen_file
= get_file(file
);
228 spin_unlock(&fc
->lock
);
235 * Put stolen request back into fuse_file->reserved_req
237 static void put_reserved_req(struct fuse_conn
*fc
, struct fuse_req
*req
)
239 struct file
*file
= req
->stolen_file
;
240 struct fuse_file
*ff
= file
->private_data
;
242 spin_lock(&fc
->lock
);
243 fuse_request_init(req
, req
->pages
, req
->page_descs
, req
->max_pages
);
244 BUG_ON(ff
->reserved_req
);
245 ff
->reserved_req
= req
;
246 wake_up_all(&fc
->reserved_req_waitq
);
247 spin_unlock(&fc
->lock
);
252 * Gets a requests for a file operation, always succeeds
254 * This is used for sending the FLUSH request, which must get to
255 * userspace, due to POSIX locks which may need to be unlocked.
257 * If allocation fails due to OOM, use the reserved request in
260 * This is very unlikely to deadlock accidentally, since the
261 * filesystem should not have it's own file open. If deadlock is
262 * intentional, it can still be broken by "aborting" the filesystem.
264 struct fuse_req
*fuse_get_req_nofail_nopages(struct fuse_conn
*fc
,
267 struct fuse_req
*req
;
269 atomic_inc(&fc
->num_waiting
);
270 wait_event(fc
->blocked_waitq
, fc
->initialized
);
271 /* Matches smp_wmb() in fuse_set_initialized() */
273 req
= fuse_request_alloc(0);
275 req
= get_reserved_req(fc
, file
);
277 fuse_req_init_context(req
);
278 __set_bit(FR_WAITING
, &req
->flags
);
279 __clear_bit(FR_BACKGROUND
, &req
->flags
);
283 void fuse_put_request(struct fuse_conn
*fc
, struct fuse_req
*req
)
285 if (atomic_dec_and_test(&req
->count
)) {
286 if (test_bit(FR_BACKGROUND
, &req
->flags
)) {
288 * We get here in the unlikely case that a background
289 * request was allocated but not sent
291 spin_lock(&fc
->lock
);
293 wake_up(&fc
->blocked_waitq
);
294 spin_unlock(&fc
->lock
);
297 if (test_bit(FR_WAITING
, &req
->flags
)) {
298 __clear_bit(FR_WAITING
, &req
->flags
);
299 atomic_dec(&fc
->num_waiting
);
302 if (req
->stolen_file
)
303 put_reserved_req(fc
, req
);
305 fuse_request_free(req
);
308 EXPORT_SYMBOL_GPL(fuse_put_request
);
310 static unsigned len_args(unsigned numargs
, struct fuse_arg
*args
)
315 for (i
= 0; i
< numargs
; i
++)
316 nbytes
+= args
[i
].size
;
321 static u64
fuse_get_unique(struct fuse_iqueue
*fiq
)
323 return ++fiq
->reqctr
;
326 static void queue_request(struct fuse_iqueue
*fiq
, struct fuse_req
*req
)
328 req
->in
.h
.len
= sizeof(struct fuse_in_header
) +
329 len_args(req
->in
.numargs
, (struct fuse_arg
*) req
->in
.args
);
330 list_add_tail(&req
->list
, &fiq
->pending
);
331 wake_up_locked(&fiq
->waitq
);
332 kill_fasync(&fiq
->fasync
, SIGIO
, POLL_IN
);
335 void fuse_queue_forget(struct fuse_conn
*fc
, struct fuse_forget_link
*forget
,
336 u64 nodeid
, u64 nlookup
)
338 struct fuse_iqueue
*fiq
= &fc
->iq
;
340 forget
->forget_one
.nodeid
= nodeid
;
341 forget
->forget_one
.nlookup
= nlookup
;
343 spin_lock(&fiq
->waitq
.lock
);
344 if (fiq
->connected
) {
345 fiq
->forget_list_tail
->next
= forget
;
346 fiq
->forget_list_tail
= forget
;
347 wake_up_locked(&fiq
->waitq
);
348 kill_fasync(&fiq
->fasync
, SIGIO
, POLL_IN
);
352 spin_unlock(&fiq
->waitq
.lock
);
355 static void flush_bg_queue(struct fuse_conn
*fc
)
357 while (fc
->active_background
< fc
->max_background
&&
358 !list_empty(&fc
->bg_queue
)) {
359 struct fuse_req
*req
;
360 struct fuse_iqueue
*fiq
= &fc
->iq
;
362 req
= list_entry(fc
->bg_queue
.next
, struct fuse_req
, list
);
363 list_del(&req
->list
);
364 fc
->active_background
++;
365 spin_lock(&fiq
->waitq
.lock
);
366 req
->in
.h
.unique
= fuse_get_unique(fiq
);
367 queue_request(fiq
, req
);
368 spin_unlock(&fiq
->waitq
.lock
);
373 * This function is called when a request is finished. Either a reply
374 * has arrived or it was aborted (and not yet sent) or some error
375 * occurred during communication with userspace, or the device file
376 * was closed. The requester thread is woken up (if still waiting),
377 * the 'end' callback is called if given, else the reference to the
378 * request is released
380 static void request_end(struct fuse_conn
*fc
, struct fuse_req
*req
)
382 struct fuse_iqueue
*fiq
= &fc
->iq
;
384 if (test_and_set_bit(FR_FINISHED
, &req
->flags
))
387 spin_lock(&fiq
->waitq
.lock
);
388 list_del_init(&req
->intr_entry
);
389 spin_unlock(&fiq
->waitq
.lock
);
390 WARN_ON(test_bit(FR_PENDING
, &req
->flags
));
391 WARN_ON(test_bit(FR_SENT
, &req
->flags
));
392 if (test_bit(FR_BACKGROUND
, &req
->flags
)) {
393 spin_lock(&fc
->lock
);
394 clear_bit(FR_BACKGROUND
, &req
->flags
);
395 if (fc
->num_background
== fc
->max_background
)
398 /* Wake up next waiter, if any */
399 if (!fc
->blocked
&& waitqueue_active(&fc
->blocked_waitq
))
400 wake_up(&fc
->blocked_waitq
);
402 if (fc
->num_background
== fc
->congestion_threshold
&&
403 fc
->connected
&& fc
->bdi_initialized
) {
404 clear_bdi_congested(&fc
->bdi
, BLK_RW_SYNC
);
405 clear_bdi_congested(&fc
->bdi
, BLK_RW_ASYNC
);
407 fc
->num_background
--;
408 fc
->active_background
--;
410 spin_unlock(&fc
->lock
);
412 wake_up(&req
->waitq
);
415 fuse_put_request(fc
, req
);
418 static void queue_interrupt(struct fuse_iqueue
*fiq
, struct fuse_req
*req
)
420 spin_lock(&fiq
->waitq
.lock
);
421 if (list_empty(&req
->intr_entry
)) {
422 list_add_tail(&req
->intr_entry
, &fiq
->interrupts
);
423 wake_up_locked(&fiq
->waitq
);
425 spin_unlock(&fiq
->waitq
.lock
);
426 kill_fasync(&fiq
->fasync
, SIGIO
, POLL_IN
);
429 static void request_wait_answer(struct fuse_conn
*fc
, struct fuse_req
*req
)
431 struct fuse_iqueue
*fiq
= &fc
->iq
;
434 if (!fc
->no_interrupt
) {
435 /* Any signal may interrupt this */
436 err
= wait_event_interruptible(req
->waitq
,
437 test_bit(FR_FINISHED
, &req
->flags
));
441 set_bit(FR_INTERRUPTED
, &req
->flags
);
442 /* matches barrier in fuse_dev_do_read() */
443 smp_mb__after_atomic();
444 if (test_bit(FR_SENT
, &req
->flags
))
445 queue_interrupt(fiq
, req
);
448 if (!test_bit(FR_FORCE
, &req
->flags
)) {
451 /* Only fatal signals may interrupt this */
453 err
= wait_event_interruptible(req
->waitq
,
454 test_bit(FR_FINISHED
, &req
->flags
));
455 restore_sigs(&oldset
);
460 spin_lock(&fiq
->waitq
.lock
);
461 /* Request is not yet in userspace, bail out */
462 if (test_bit(FR_PENDING
, &req
->flags
)) {
463 list_del(&req
->list
);
464 spin_unlock(&fiq
->waitq
.lock
);
465 __fuse_put_request(req
);
466 req
->out
.h
.error
= -EINTR
;
469 spin_unlock(&fiq
->waitq
.lock
);
473 * Either request is already in userspace, or it was forced.
476 wait_event(req
->waitq
, test_bit(FR_FINISHED
, &req
->flags
));
479 static void __fuse_request_send(struct fuse_conn
*fc
, struct fuse_req
*req
)
481 struct fuse_iqueue
*fiq
= &fc
->iq
;
483 BUG_ON(test_bit(FR_BACKGROUND
, &req
->flags
));
484 spin_lock(&fiq
->waitq
.lock
);
485 if (!fiq
->connected
) {
486 spin_unlock(&fiq
->waitq
.lock
);
487 req
->out
.h
.error
= -ENOTCONN
;
489 req
->in
.h
.unique
= fuse_get_unique(fiq
);
490 queue_request(fiq
, req
);
491 /* acquire extra reference, since request is still needed
492 after request_end() */
493 __fuse_get_request(req
);
494 spin_unlock(&fiq
->waitq
.lock
);
496 request_wait_answer(fc
, req
);
497 /* Pairs with smp_wmb() in request_end() */
502 void fuse_request_send(struct fuse_conn
*fc
, struct fuse_req
*req
)
504 __set_bit(FR_ISREPLY
, &req
->flags
);
505 if (!test_bit(FR_WAITING
, &req
->flags
)) {
506 __set_bit(FR_WAITING
, &req
->flags
);
507 atomic_inc(&fc
->num_waiting
);
509 __fuse_request_send(fc
, req
);
511 EXPORT_SYMBOL_GPL(fuse_request_send
);
513 static void fuse_adjust_compat(struct fuse_conn
*fc
, struct fuse_args
*args
)
515 if (fc
->minor
< 4 && args
->in
.h
.opcode
== FUSE_STATFS
)
516 args
->out
.args
[0].size
= FUSE_COMPAT_STATFS_SIZE
;
519 switch (args
->in
.h
.opcode
) {
526 args
->out
.args
[0].size
= FUSE_COMPAT_ENTRY_OUT_SIZE
;
530 args
->out
.args
[0].size
= FUSE_COMPAT_ATTR_OUT_SIZE
;
534 if (fc
->minor
< 12) {
535 switch (args
->in
.h
.opcode
) {
537 args
->in
.args
[0].size
= sizeof(struct fuse_open_in
);
540 args
->in
.args
[0].size
= FUSE_COMPAT_MKNOD_IN_SIZE
;
546 ssize_t
fuse_simple_request(struct fuse_conn
*fc
, struct fuse_args
*args
)
548 struct fuse_req
*req
;
551 req
= fuse_get_req(fc
, 0);
555 /* Needs to be done after fuse_get_req() so that fc->minor is valid */
556 fuse_adjust_compat(fc
, args
);
558 req
->in
.h
.opcode
= args
->in
.h
.opcode
;
559 req
->in
.h
.nodeid
= args
->in
.h
.nodeid
;
560 req
->in
.numargs
= args
->in
.numargs
;
561 memcpy(req
->in
.args
, args
->in
.args
,
562 args
->in
.numargs
* sizeof(struct fuse_in_arg
));
563 req
->out
.argvar
= args
->out
.argvar
;
564 req
->out
.numargs
= args
->out
.numargs
;
565 memcpy(req
->out
.args
, args
->out
.args
,
566 args
->out
.numargs
* sizeof(struct fuse_arg
));
567 fuse_request_send(fc
, req
);
568 ret
= req
->out
.h
.error
;
569 if (!ret
&& args
->out
.argvar
) {
570 BUG_ON(args
->out
.numargs
!= 1);
571 ret
= req
->out
.args
[0].size
;
573 fuse_put_request(fc
, req
);
579 * Called under fc->lock
581 * fc->connected must have been checked previously
583 void fuse_request_send_background_locked(struct fuse_conn
*fc
,
584 struct fuse_req
*req
)
586 BUG_ON(!test_bit(FR_BACKGROUND
, &req
->flags
));
587 if (!test_bit(FR_WAITING
, &req
->flags
)) {
588 __set_bit(FR_WAITING
, &req
->flags
);
589 atomic_inc(&fc
->num_waiting
);
591 __set_bit(FR_ISREPLY
, &req
->flags
);
592 fc
->num_background
++;
593 if (fc
->num_background
== fc
->max_background
)
595 if (fc
->num_background
== fc
->congestion_threshold
&&
596 fc
->bdi_initialized
) {
597 set_bdi_congested(&fc
->bdi
, BLK_RW_SYNC
);
598 set_bdi_congested(&fc
->bdi
, BLK_RW_ASYNC
);
600 list_add_tail(&req
->list
, &fc
->bg_queue
);
604 void fuse_request_send_background(struct fuse_conn
*fc
, struct fuse_req
*req
)
607 spin_lock(&fc
->lock
);
609 fuse_request_send_background_locked(fc
, req
);
610 spin_unlock(&fc
->lock
);
612 spin_unlock(&fc
->lock
);
613 req
->out
.h
.error
= -ENOTCONN
;
615 fuse_put_request(fc
, req
);
618 EXPORT_SYMBOL_GPL(fuse_request_send_background
);
620 static int fuse_request_send_notify_reply(struct fuse_conn
*fc
,
621 struct fuse_req
*req
, u64 unique
)
624 struct fuse_iqueue
*fiq
= &fc
->iq
;
626 __clear_bit(FR_ISREPLY
, &req
->flags
);
627 req
->in
.h
.unique
= unique
;
628 spin_lock(&fiq
->waitq
.lock
);
629 if (fiq
->connected
) {
630 queue_request(fiq
, req
);
633 spin_unlock(&fiq
->waitq
.lock
);
638 void fuse_force_forget(struct file
*file
, u64 nodeid
)
640 struct inode
*inode
= file_inode(file
);
641 struct fuse_conn
*fc
= get_fuse_conn(inode
);
642 struct fuse_req
*req
;
643 struct fuse_forget_in inarg
;
645 memset(&inarg
, 0, sizeof(inarg
));
647 req
= fuse_get_req_nofail_nopages(fc
, file
);
648 req
->in
.h
.opcode
= FUSE_FORGET
;
649 req
->in
.h
.nodeid
= nodeid
;
651 req
->in
.args
[0].size
= sizeof(inarg
);
652 req
->in
.args
[0].value
= &inarg
;
653 __clear_bit(FR_ISREPLY
, &req
->flags
);
654 __fuse_request_send(fc
, req
);
656 fuse_put_request(fc
, req
);
660 * Lock the request. Up to the next unlock_request() there mustn't be
661 * anything that could cause a page-fault. If the request was already
664 static int lock_request(struct fuse_req
*req
)
668 spin_lock(&req
->waitq
.lock
);
669 if (test_bit(FR_ABORTED
, &req
->flags
))
672 set_bit(FR_LOCKED
, &req
->flags
);
673 spin_unlock(&req
->waitq
.lock
);
679 * Unlock request. If it was aborted while locked, caller is responsible
680 * for unlocking and ending the request.
682 static int unlock_request(struct fuse_req
*req
)
686 spin_lock(&req
->waitq
.lock
);
687 if (test_bit(FR_ABORTED
, &req
->flags
))
690 clear_bit(FR_LOCKED
, &req
->flags
);
691 spin_unlock(&req
->waitq
.lock
);
696 struct fuse_copy_state
{
698 struct fuse_req
*req
;
699 struct iov_iter
*iter
;
700 struct pipe_buffer
*pipebufs
;
701 struct pipe_buffer
*currbuf
;
702 struct pipe_inode_info
*pipe
;
703 unsigned long nr_segs
;
707 unsigned move_pages
:1;
710 static void fuse_copy_init(struct fuse_copy_state
*cs
, int write
,
711 struct iov_iter
*iter
)
713 memset(cs
, 0, sizeof(*cs
));
718 /* Unmap and put previous page of userspace buffer */
719 static void fuse_copy_finish(struct fuse_copy_state
*cs
)
722 struct pipe_buffer
*buf
= cs
->currbuf
;
725 buf
->len
= PAGE_SIZE
- cs
->len
;
729 flush_dcache_page(cs
->pg
);
730 set_page_dirty_lock(cs
->pg
);
738 * Get another pagefull of userspace buffer, and map it to kernel
739 * address space, and lock request
741 static int fuse_copy_fill(struct fuse_copy_state
*cs
)
746 err
= unlock_request(cs
->req
);
750 fuse_copy_finish(cs
);
752 struct pipe_buffer
*buf
= cs
->pipebufs
;
755 err
= buf
->ops
->confirm(cs
->pipe
, buf
);
759 BUG_ON(!cs
->nr_segs
);
762 cs
->offset
= buf
->offset
;
767 if (cs
->nr_segs
== cs
->pipe
->buffers
)
770 page
= alloc_page(GFP_HIGHUSER
);
787 err
= iov_iter_get_pages(cs
->iter
, &page
, PAGE_SIZE
, 1, &off
);
795 iov_iter_advance(cs
->iter
, err
);
798 return lock_request(cs
->req
);
801 /* Do as much copy to/from userspace buffer as we can */
802 static int fuse_copy_do(struct fuse_copy_state
*cs
, void **val
, unsigned *size
)
804 unsigned ncpy
= min(*size
, cs
->len
);
806 void *pgaddr
= kmap_atomic(cs
->pg
);
807 void *buf
= pgaddr
+ cs
->offset
;
810 memcpy(buf
, *val
, ncpy
);
812 memcpy(*val
, buf
, ncpy
);
814 kunmap_atomic(pgaddr
);
823 static int fuse_check_page(struct page
*page
)
825 if (page_mapcount(page
) ||
826 page
->mapping
!= NULL
||
827 page_count(page
) != 1 ||
828 (page
->flags
& PAGE_FLAGS_CHECK_AT_PREP
&
835 printk(KERN_WARNING
"fuse: trying to steal weird page\n");
836 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
);
842 static int fuse_try_move_page(struct fuse_copy_state
*cs
, struct page
**pagep
)
845 struct page
*oldpage
= *pagep
;
846 struct page
*newpage
;
847 struct pipe_buffer
*buf
= cs
->pipebufs
;
849 err
= unlock_request(cs
->req
);
853 fuse_copy_finish(cs
);
855 err
= buf
->ops
->confirm(cs
->pipe
, buf
);
859 BUG_ON(!cs
->nr_segs
);
865 if (cs
->len
!= PAGE_SIZE
)
868 if (buf
->ops
->steal(cs
->pipe
, buf
) != 0)
873 if (!PageUptodate(newpage
))
874 SetPageUptodate(newpage
);
876 ClearPageMappedToDisk(newpage
);
878 if (fuse_check_page(newpage
) != 0)
879 goto out_fallback_unlock
;
882 * This is a new and locked page, it shouldn't be mapped or
883 * have any special flags on it
885 if (WARN_ON(page_mapped(oldpage
)))
886 goto out_fallback_unlock
;
887 if (WARN_ON(page_has_private(oldpage
)))
888 goto out_fallback_unlock
;
889 if (WARN_ON(PageDirty(oldpage
) || PageWriteback(oldpage
)))
890 goto out_fallback_unlock
;
891 if (WARN_ON(PageMlocked(oldpage
)))
892 goto out_fallback_unlock
;
894 err
= replace_page_cache_page(oldpage
, newpage
, GFP_KERNEL
);
896 unlock_page(newpage
);
900 page_cache_get(newpage
);
902 if (!(buf
->flags
& PIPE_BUF_FLAG_LRU
))
903 lru_cache_add_file(newpage
);
906 spin_lock(&cs
->req
->waitq
.lock
);
907 if (test_bit(FR_ABORTED
, &cs
->req
->flags
))
911 spin_unlock(&cs
->req
->waitq
.lock
);
914 unlock_page(newpage
);
915 page_cache_release(newpage
);
919 unlock_page(oldpage
);
920 page_cache_release(oldpage
);
926 unlock_page(newpage
);
929 cs
->offset
= buf
->offset
;
931 err
= lock_request(cs
->req
);
938 static int fuse_ref_page(struct fuse_copy_state
*cs
, struct page
*page
,
939 unsigned offset
, unsigned count
)
941 struct pipe_buffer
*buf
;
944 if (cs
->nr_segs
== cs
->pipe
->buffers
)
947 err
= unlock_request(cs
->req
);
951 fuse_copy_finish(cs
);
954 page_cache_get(page
);
956 buf
->offset
= offset
;
967 * Copy a page in the request to/from the userspace buffer. Must be
970 static int fuse_copy_page(struct fuse_copy_state
*cs
, struct page
**pagep
,
971 unsigned offset
, unsigned count
, int zeroing
)
974 struct page
*page
= *pagep
;
976 if (page
&& zeroing
&& count
< PAGE_SIZE
)
977 clear_highpage(page
);
980 if (cs
->write
&& cs
->pipebufs
&& page
) {
981 return fuse_ref_page(cs
, page
, offset
, count
);
982 } else if (!cs
->len
) {
983 if (cs
->move_pages
&& page
&&
984 offset
== 0 && count
== PAGE_SIZE
) {
985 err
= fuse_try_move_page(cs
, pagep
);
989 err
= fuse_copy_fill(cs
);
995 void *mapaddr
= kmap_atomic(page
);
996 void *buf
= mapaddr
+ offset
;
997 offset
+= fuse_copy_do(cs
, &buf
, &count
);
998 kunmap_atomic(mapaddr
);
1000 offset
+= fuse_copy_do(cs
, NULL
, &count
);
1002 if (page
&& !cs
->write
)
1003 flush_dcache_page(page
);
1007 /* Copy pages in the request to/from userspace buffer */
1008 static int fuse_copy_pages(struct fuse_copy_state
*cs
, unsigned nbytes
,
1012 struct fuse_req
*req
= cs
->req
;
1014 for (i
= 0; i
< req
->num_pages
&& (nbytes
|| zeroing
); i
++) {
1016 unsigned offset
= req
->page_descs
[i
].offset
;
1017 unsigned count
= min(nbytes
, req
->page_descs
[i
].length
);
1019 err
= fuse_copy_page(cs
, &req
->pages
[i
], offset
, count
,
1029 /* Copy a single argument in the request to/from userspace buffer */
1030 static int fuse_copy_one(struct fuse_copy_state
*cs
, void *val
, unsigned size
)
1034 int err
= fuse_copy_fill(cs
);
1038 fuse_copy_do(cs
, &val
, &size
);
1043 /* Copy request arguments to/from userspace buffer */
1044 static int fuse_copy_args(struct fuse_copy_state
*cs
, unsigned numargs
,
1045 unsigned argpages
, struct fuse_arg
*args
,
1051 for (i
= 0; !err
&& i
< numargs
; i
++) {
1052 struct fuse_arg
*arg
= &args
[i
];
1053 if (i
== numargs
- 1 && argpages
)
1054 err
= fuse_copy_pages(cs
, arg
->size
, zeroing
);
1056 err
= fuse_copy_one(cs
, arg
->value
, arg
->size
);
1061 static int forget_pending(struct fuse_iqueue
*fiq
)
1063 return fiq
->forget_list_head
.next
!= NULL
;
1066 static int request_pending(struct fuse_iqueue
*fiq
)
1068 return !list_empty(&fiq
->pending
) || !list_empty(&fiq
->interrupts
) ||
1069 forget_pending(fiq
);
1073 * Transfer an interrupt request to userspace
1075 * Unlike other requests this is assembled on demand, without a need
1076 * to allocate a separate fuse_req structure.
1078 * Called with fiq->waitq.lock held, releases it
1080 static int fuse_read_interrupt(struct fuse_iqueue
*fiq
,
1081 struct fuse_copy_state
*cs
,
1082 size_t nbytes
, struct fuse_req
*req
)
1083 __releases(fiq
->waitq
.lock
)
1085 struct fuse_in_header ih
;
1086 struct fuse_interrupt_in arg
;
1087 unsigned reqsize
= sizeof(ih
) + sizeof(arg
);
1090 list_del_init(&req
->intr_entry
);
1091 req
->intr_unique
= fuse_get_unique(fiq
);
1092 memset(&ih
, 0, sizeof(ih
));
1093 memset(&arg
, 0, sizeof(arg
));
1095 ih
.opcode
= FUSE_INTERRUPT
;
1096 ih
.unique
= req
->intr_unique
;
1097 arg
.unique
= req
->in
.h
.unique
;
1099 spin_unlock(&fiq
->waitq
.lock
);
1100 if (nbytes
< reqsize
)
1103 err
= fuse_copy_one(cs
, &ih
, sizeof(ih
));
1105 err
= fuse_copy_one(cs
, &arg
, sizeof(arg
));
1106 fuse_copy_finish(cs
);
1108 return err
? err
: reqsize
;
1111 static struct fuse_forget_link
*dequeue_forget(struct fuse_iqueue
*fiq
,
1115 struct fuse_forget_link
*head
= fiq
->forget_list_head
.next
;
1116 struct fuse_forget_link
**newhead
= &head
;
1119 for (count
= 0; *newhead
!= NULL
&& count
< max
; count
++)
1120 newhead
= &(*newhead
)->next
;
1122 fiq
->forget_list_head
.next
= *newhead
;
1124 if (fiq
->forget_list_head
.next
== NULL
)
1125 fiq
->forget_list_tail
= &fiq
->forget_list_head
;
1133 static int fuse_read_single_forget(struct fuse_iqueue
*fiq
,
1134 struct fuse_copy_state
*cs
,
1136 __releases(fiq
->waitq
.lock
)
1139 struct fuse_forget_link
*forget
= dequeue_forget(fiq
, 1, NULL
);
1140 struct fuse_forget_in arg
= {
1141 .nlookup
= forget
->forget_one
.nlookup
,
1143 struct fuse_in_header ih
= {
1144 .opcode
= FUSE_FORGET
,
1145 .nodeid
= forget
->forget_one
.nodeid
,
1146 .unique
= fuse_get_unique(fiq
),
1147 .len
= sizeof(ih
) + sizeof(arg
),
1150 spin_unlock(&fiq
->waitq
.lock
);
1152 if (nbytes
< ih
.len
)
1155 err
= fuse_copy_one(cs
, &ih
, sizeof(ih
));
1157 err
= fuse_copy_one(cs
, &arg
, sizeof(arg
));
1158 fuse_copy_finish(cs
);
1166 static int fuse_read_batch_forget(struct fuse_iqueue
*fiq
,
1167 struct fuse_copy_state
*cs
, size_t nbytes
)
1168 __releases(fiq
->waitq
.lock
)
1171 unsigned max_forgets
;
1173 struct fuse_forget_link
*head
;
1174 struct fuse_batch_forget_in arg
= { .count
= 0 };
1175 struct fuse_in_header ih
= {
1176 .opcode
= FUSE_BATCH_FORGET
,
1177 .unique
= fuse_get_unique(fiq
),
1178 .len
= sizeof(ih
) + sizeof(arg
),
1181 if (nbytes
< ih
.len
) {
1182 spin_unlock(&fiq
->waitq
.lock
);
1186 max_forgets
= (nbytes
- ih
.len
) / sizeof(struct fuse_forget_one
);
1187 head
= dequeue_forget(fiq
, max_forgets
, &count
);
1188 spin_unlock(&fiq
->waitq
.lock
);
1191 ih
.len
+= count
* sizeof(struct fuse_forget_one
);
1192 err
= fuse_copy_one(cs
, &ih
, sizeof(ih
));
1194 err
= fuse_copy_one(cs
, &arg
, sizeof(arg
));
1197 struct fuse_forget_link
*forget
= head
;
1200 err
= fuse_copy_one(cs
, &forget
->forget_one
,
1201 sizeof(forget
->forget_one
));
1203 head
= forget
->next
;
1207 fuse_copy_finish(cs
);
1215 static int fuse_read_forget(struct fuse_conn
*fc
, struct fuse_iqueue
*fiq
,
1216 struct fuse_copy_state
*cs
,
1218 __releases(fiq
->waitq
.lock
)
1220 if (fc
->minor
< 16 || fiq
->forget_list_head
.next
->next
== NULL
)
1221 return fuse_read_single_forget(fiq
, cs
, nbytes
);
1223 return fuse_read_batch_forget(fiq
, cs
, nbytes
);
1227 * Read a single request into the userspace filesystem's buffer. This
1228 * function waits until a request is available, then removes it from
1229 * the pending list and copies request data to userspace buffer. If
1230 * no reply is needed (FORGET) or request has been aborted or there
1231 * was an error during the copying then it's finished by calling
1232 * request_end(). Otherwise add it to the processing list, and set
1235 static ssize_t
fuse_dev_do_read(struct fuse_conn
*fc
, struct file
*file
,
1236 struct fuse_copy_state
*cs
, size_t nbytes
)
1239 struct fuse_iqueue
*fiq
= &fc
->iq
;
1240 struct fuse_pqueue
*fpq
= &fc
->pq
;
1241 struct fuse_req
*req
;
1246 spin_lock(&fiq
->waitq
.lock
);
1248 if ((file
->f_flags
& O_NONBLOCK
) && fiq
->connected
&&
1249 !request_pending(fiq
))
1252 err
= wait_event_interruptible_exclusive_locked(fiq
->waitq
,
1253 !fiq
->connected
|| request_pending(fiq
));
1258 if (!fiq
->connected
)
1261 if (!list_empty(&fiq
->interrupts
)) {
1262 req
= list_entry(fiq
->interrupts
.next
, struct fuse_req
,
1264 return fuse_read_interrupt(fiq
, cs
, nbytes
, req
);
1267 if (forget_pending(fiq
)) {
1268 if (list_empty(&fiq
->pending
) || fiq
->forget_batch
-- > 0)
1269 return fuse_read_forget(fc
, fiq
, cs
, nbytes
);
1271 if (fiq
->forget_batch
<= -8)
1272 fiq
->forget_batch
= 16;
1275 req
= list_entry(fiq
->pending
.next
, struct fuse_req
, list
);
1276 clear_bit(FR_PENDING
, &req
->flags
);
1277 list_del_init(&req
->list
);
1278 spin_unlock(&fiq
->waitq
.lock
);
1281 reqsize
= in
->h
.len
;
1282 /* If request is too large, reply with an error and restart the read */
1283 if (nbytes
< reqsize
) {
1284 req
->out
.h
.error
= -EIO
;
1285 /* SETXATTR is special, since it may contain too large data */
1286 if (in
->h
.opcode
== FUSE_SETXATTR
)
1287 req
->out
.h
.error
= -E2BIG
;
1288 request_end(fc
, req
);
1291 spin_lock(&fpq
->lock
);
1292 list_add(&req
->list
, &fpq
->io
);
1293 spin_unlock(&fpq
->lock
);
1295 err
= fuse_copy_one(cs
, &in
->h
, sizeof(in
->h
));
1297 err
= fuse_copy_args(cs
, in
->numargs
, in
->argpages
,
1298 (struct fuse_arg
*) in
->args
, 0);
1299 fuse_copy_finish(cs
);
1300 spin_lock(&fpq
->lock
);
1301 clear_bit(FR_LOCKED
, &req
->flags
);
1302 if (!fpq
->connected
) {
1307 req
->out
.h
.error
= -EIO
;
1310 if (!test_bit(FR_ISREPLY
, &req
->flags
)) {
1314 list_move_tail(&req
->list
, &fpq
->processing
);
1315 spin_unlock(&fpq
->lock
);
1316 set_bit(FR_SENT
, &req
->flags
);
1317 /* matches barrier in request_wait_answer() */
1318 smp_mb__after_atomic();
1319 if (test_bit(FR_INTERRUPTED
, &req
->flags
))
1320 queue_interrupt(fiq
, req
);
1325 if (!test_bit(FR_PRIVATE
, &req
->flags
))
1326 list_del_init(&req
->list
);
1327 spin_unlock(&fpq
->lock
);
1328 request_end(fc
, req
);
1332 spin_unlock(&fiq
->waitq
.lock
);
1336 static int fuse_dev_open(struct inode
*inode
, struct file
*file
)
1339 * The fuse device's file's private_data is used to hold
1340 * the fuse_conn(ection) when it is mounted, and is used to
1341 * keep track of whether the file has been mounted already.
1343 file
->private_data
= NULL
;
1347 static ssize_t
fuse_dev_read(struct kiocb
*iocb
, struct iov_iter
*to
)
1349 struct fuse_copy_state cs
;
1350 struct file
*file
= iocb
->ki_filp
;
1351 struct fuse_conn
*fc
= fuse_get_conn(file
);
1355 if (!iter_is_iovec(to
))
1358 fuse_copy_init(&cs
, 1, to
);
1360 return fuse_dev_do_read(fc
, file
, &cs
, iov_iter_count(to
));
1363 static ssize_t
fuse_dev_splice_read(struct file
*in
, loff_t
*ppos
,
1364 struct pipe_inode_info
*pipe
,
1365 size_t len
, unsigned int flags
)
1370 struct pipe_buffer
*bufs
;
1371 struct fuse_copy_state cs
;
1372 struct fuse_conn
*fc
= fuse_get_conn(in
);
1376 bufs
= kmalloc(pipe
->buffers
* sizeof(struct pipe_buffer
), GFP_KERNEL
);
1380 fuse_copy_init(&cs
, 1, NULL
);
1383 ret
= fuse_dev_do_read(fc
, in
, &cs
, len
);
1390 if (!pipe
->readers
) {
1391 send_sig(SIGPIPE
, current
, 0);
1397 if (pipe
->nrbufs
+ cs
.nr_segs
> pipe
->buffers
) {
1402 while (page_nr
< cs
.nr_segs
) {
1403 int newbuf
= (pipe
->curbuf
+ pipe
->nrbufs
) & (pipe
->buffers
- 1);
1404 struct pipe_buffer
*buf
= pipe
->bufs
+ newbuf
;
1406 buf
->page
= bufs
[page_nr
].page
;
1407 buf
->offset
= bufs
[page_nr
].offset
;
1408 buf
->len
= bufs
[page_nr
].len
;
1410 * Need to be careful about this. Having buf->ops in module
1411 * code can Oops if the buffer persists after module unload.
1413 buf
->ops
= &nosteal_pipe_buf_ops
;
1428 if (waitqueue_active(&pipe
->wait
))
1429 wake_up_interruptible(&pipe
->wait
);
1430 kill_fasync(&pipe
->fasync_readers
, SIGIO
, POLL_IN
);
1434 for (; page_nr
< cs
.nr_segs
; page_nr
++)
1435 page_cache_release(bufs
[page_nr
].page
);
1441 static int fuse_notify_poll(struct fuse_conn
*fc
, unsigned int size
,
1442 struct fuse_copy_state
*cs
)
1444 struct fuse_notify_poll_wakeup_out outarg
;
1447 if (size
!= sizeof(outarg
))
1450 err
= fuse_copy_one(cs
, &outarg
, sizeof(outarg
));
1454 fuse_copy_finish(cs
);
1455 return fuse_notify_poll_wakeup(fc
, &outarg
);
1458 fuse_copy_finish(cs
);
1462 static int fuse_notify_inval_inode(struct fuse_conn
*fc
, unsigned int size
,
1463 struct fuse_copy_state
*cs
)
1465 struct fuse_notify_inval_inode_out outarg
;
1468 if (size
!= sizeof(outarg
))
1471 err
= fuse_copy_one(cs
, &outarg
, sizeof(outarg
));
1474 fuse_copy_finish(cs
);
1476 down_read(&fc
->killsb
);
1479 err
= fuse_reverse_inval_inode(fc
->sb
, outarg
.ino
,
1480 outarg
.off
, outarg
.len
);
1482 up_read(&fc
->killsb
);
1486 fuse_copy_finish(cs
);
1490 static int fuse_notify_inval_entry(struct fuse_conn
*fc
, unsigned int size
,
1491 struct fuse_copy_state
*cs
)
1493 struct fuse_notify_inval_entry_out outarg
;
1498 buf
= kzalloc(FUSE_NAME_MAX
+ 1, GFP_KERNEL
);
1503 if (size
< sizeof(outarg
))
1506 err
= fuse_copy_one(cs
, &outarg
, sizeof(outarg
));
1510 err
= -ENAMETOOLONG
;
1511 if (outarg
.namelen
> FUSE_NAME_MAX
)
1515 if (size
!= sizeof(outarg
) + outarg
.namelen
+ 1)
1519 name
.len
= outarg
.namelen
;
1520 err
= fuse_copy_one(cs
, buf
, outarg
.namelen
+ 1);
1523 fuse_copy_finish(cs
);
1524 buf
[outarg
.namelen
] = 0;
1525 name
.hash
= full_name_hash(name
.name
, name
.len
);
1527 down_read(&fc
->killsb
);
1530 err
= fuse_reverse_inval_entry(fc
->sb
, outarg
.parent
, 0, &name
);
1531 up_read(&fc
->killsb
);
1537 fuse_copy_finish(cs
);
1541 static int fuse_notify_delete(struct fuse_conn
*fc
, unsigned int size
,
1542 struct fuse_copy_state
*cs
)
1544 struct fuse_notify_delete_out outarg
;
1549 buf
= kzalloc(FUSE_NAME_MAX
+ 1, GFP_KERNEL
);
1554 if (size
< sizeof(outarg
))
1557 err
= fuse_copy_one(cs
, &outarg
, sizeof(outarg
));
1561 err
= -ENAMETOOLONG
;
1562 if (outarg
.namelen
> FUSE_NAME_MAX
)
1566 if (size
!= sizeof(outarg
) + outarg
.namelen
+ 1)
1570 name
.len
= outarg
.namelen
;
1571 err
= fuse_copy_one(cs
, buf
, outarg
.namelen
+ 1);
1574 fuse_copy_finish(cs
);
1575 buf
[outarg
.namelen
] = 0;
1576 name
.hash
= full_name_hash(name
.name
, name
.len
);
1578 down_read(&fc
->killsb
);
1581 err
= fuse_reverse_inval_entry(fc
->sb
, outarg
.parent
,
1582 outarg
.child
, &name
);
1583 up_read(&fc
->killsb
);
1589 fuse_copy_finish(cs
);
1593 static int fuse_notify_store(struct fuse_conn
*fc
, unsigned int size
,
1594 struct fuse_copy_state
*cs
)
1596 struct fuse_notify_store_out outarg
;
1597 struct inode
*inode
;
1598 struct address_space
*mapping
;
1602 unsigned int offset
;
1608 if (size
< sizeof(outarg
))
1611 err
= fuse_copy_one(cs
, &outarg
, sizeof(outarg
));
1616 if (size
- sizeof(outarg
) != outarg
.size
)
1619 nodeid
= outarg
.nodeid
;
1621 down_read(&fc
->killsb
);
1627 inode
= ilookup5(fc
->sb
, nodeid
, fuse_inode_eq
, &nodeid
);
1631 mapping
= inode
->i_mapping
;
1632 index
= outarg
.offset
>> PAGE_CACHE_SHIFT
;
1633 offset
= outarg
.offset
& ~PAGE_CACHE_MASK
;
1634 file_size
= i_size_read(inode
);
1635 end
= outarg
.offset
+ outarg
.size
;
1636 if (end
> file_size
) {
1638 fuse_write_update_size(inode
, file_size
);
1644 unsigned int this_num
;
1647 page
= find_or_create_page(mapping
, index
,
1648 mapping_gfp_mask(mapping
));
1652 this_num
= min_t(unsigned, num
, PAGE_CACHE_SIZE
- offset
);
1653 err
= fuse_copy_page(cs
, &page
, offset
, this_num
, 0);
1654 if (!err
&& offset
== 0 &&
1655 (this_num
== PAGE_CACHE_SIZE
|| file_size
== end
))
1656 SetPageUptodate(page
);
1658 page_cache_release(page
);
1673 up_read(&fc
->killsb
);
1675 fuse_copy_finish(cs
);
1679 static void fuse_retrieve_end(struct fuse_conn
*fc
, struct fuse_req
*req
)
1681 release_pages(req
->pages
, req
->num_pages
, false);
1684 static int fuse_retrieve(struct fuse_conn
*fc
, struct inode
*inode
,
1685 struct fuse_notify_retrieve_out
*outarg
)
1688 struct address_space
*mapping
= inode
->i_mapping
;
1689 struct fuse_req
*req
;
1693 unsigned int offset
;
1694 size_t total_len
= 0;
1697 offset
= outarg
->offset
& ~PAGE_CACHE_MASK
;
1698 file_size
= i_size_read(inode
);
1701 if (outarg
->offset
> file_size
)
1703 else if (outarg
->offset
+ num
> file_size
)
1704 num
= file_size
- outarg
->offset
;
1706 num_pages
= (num
+ offset
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
1707 num_pages
= min(num_pages
, FUSE_MAX_PAGES_PER_REQ
);
1709 req
= fuse_get_req(fc
, num_pages
);
1711 return PTR_ERR(req
);
1713 req
->in
.h
.opcode
= FUSE_NOTIFY_REPLY
;
1714 req
->in
.h
.nodeid
= outarg
->nodeid
;
1715 req
->in
.numargs
= 2;
1716 req
->in
.argpages
= 1;
1717 req
->page_descs
[0].offset
= offset
;
1718 req
->end
= fuse_retrieve_end
;
1720 index
= outarg
->offset
>> PAGE_CACHE_SHIFT
;
1722 while (num
&& req
->num_pages
< num_pages
) {
1724 unsigned int this_num
;
1726 page
= find_get_page(mapping
, index
);
1730 this_num
= min_t(unsigned, num
, PAGE_CACHE_SIZE
- offset
);
1731 req
->pages
[req
->num_pages
] = page
;
1732 req
->page_descs
[req
->num_pages
].length
= this_num
;
1737 total_len
+= this_num
;
1740 req
->misc
.retrieve_in
.offset
= outarg
->offset
;
1741 req
->misc
.retrieve_in
.size
= total_len
;
1742 req
->in
.args
[0].size
= sizeof(req
->misc
.retrieve_in
);
1743 req
->in
.args
[0].value
= &req
->misc
.retrieve_in
;
1744 req
->in
.args
[1].size
= total_len
;
1746 err
= fuse_request_send_notify_reply(fc
, req
, outarg
->notify_unique
);
1748 fuse_retrieve_end(fc
, req
);
1753 static int fuse_notify_retrieve(struct fuse_conn
*fc
, unsigned int size
,
1754 struct fuse_copy_state
*cs
)
1756 struct fuse_notify_retrieve_out outarg
;
1757 struct inode
*inode
;
1761 if (size
!= sizeof(outarg
))
1764 err
= fuse_copy_one(cs
, &outarg
, sizeof(outarg
));
1768 fuse_copy_finish(cs
);
1770 down_read(&fc
->killsb
);
1773 u64 nodeid
= outarg
.nodeid
;
1775 inode
= ilookup5(fc
->sb
, nodeid
, fuse_inode_eq
, &nodeid
);
1777 err
= fuse_retrieve(fc
, inode
, &outarg
);
1781 up_read(&fc
->killsb
);
1786 fuse_copy_finish(cs
);
1790 static int fuse_notify(struct fuse_conn
*fc
, enum fuse_notify_code code
,
1791 unsigned int size
, struct fuse_copy_state
*cs
)
1793 /* Don't try to move pages (yet) */
1797 case FUSE_NOTIFY_POLL
:
1798 return fuse_notify_poll(fc
, size
, cs
);
1800 case FUSE_NOTIFY_INVAL_INODE
:
1801 return fuse_notify_inval_inode(fc
, size
, cs
);
1803 case FUSE_NOTIFY_INVAL_ENTRY
:
1804 return fuse_notify_inval_entry(fc
, size
, cs
);
1806 case FUSE_NOTIFY_STORE
:
1807 return fuse_notify_store(fc
, size
, cs
);
1809 case FUSE_NOTIFY_RETRIEVE
:
1810 return fuse_notify_retrieve(fc
, size
, cs
);
1812 case FUSE_NOTIFY_DELETE
:
1813 return fuse_notify_delete(fc
, size
, cs
);
1816 fuse_copy_finish(cs
);
1821 /* Look up request on processing list by unique ID */
1822 static struct fuse_req
*request_find(struct fuse_pqueue
*fpq
, u64 unique
)
1824 struct fuse_req
*req
;
1826 list_for_each_entry(req
, &fpq
->processing
, list
) {
1827 if (req
->in
.h
.unique
== unique
|| req
->intr_unique
== unique
)
1833 static int copy_out_args(struct fuse_copy_state
*cs
, struct fuse_out
*out
,
1836 unsigned reqsize
= sizeof(struct fuse_out_header
);
1839 return nbytes
!= reqsize
? -EINVAL
: 0;
1841 reqsize
+= len_args(out
->numargs
, out
->args
);
1843 if (reqsize
< nbytes
|| (reqsize
> nbytes
&& !out
->argvar
))
1845 else if (reqsize
> nbytes
) {
1846 struct fuse_arg
*lastarg
= &out
->args
[out
->numargs
-1];
1847 unsigned diffsize
= reqsize
- nbytes
;
1848 if (diffsize
> lastarg
->size
)
1850 lastarg
->size
-= diffsize
;
1852 return fuse_copy_args(cs
, out
->numargs
, out
->argpages
, out
->args
,
1857 * Write a single reply to a request. First the header is copied from
1858 * the write buffer. The request is then searched on the processing
1859 * list by the unique ID found in the header. If found, then remove
1860 * it from the list and copy the rest of the buffer to the request.
1861 * The request is finished by calling request_end()
1863 static ssize_t
fuse_dev_do_write(struct fuse_conn
*fc
,
1864 struct fuse_copy_state
*cs
, size_t nbytes
)
1867 struct fuse_pqueue
*fpq
= &fc
->pq
;
1868 struct fuse_req
*req
;
1869 struct fuse_out_header oh
;
1871 if (nbytes
< sizeof(struct fuse_out_header
))
1874 err
= fuse_copy_one(cs
, &oh
, sizeof(oh
));
1879 if (oh
.len
!= nbytes
)
1883 * Zero oh.unique indicates unsolicited notification message
1884 * and error contains notification code.
1887 err
= fuse_notify(fc
, oh
.error
, nbytes
- sizeof(oh
), cs
);
1888 return err
? err
: nbytes
;
1892 if (oh
.error
<= -1000 || oh
.error
> 0)
1895 spin_lock(&fpq
->lock
);
1897 if (!fpq
->connected
)
1900 req
= request_find(fpq
, oh
.unique
);
1904 /* Is it an interrupt reply? */
1905 if (req
->intr_unique
== oh
.unique
) {
1906 spin_unlock(&fpq
->lock
);
1909 if (nbytes
!= sizeof(struct fuse_out_header
))
1912 if (oh
.error
== -ENOSYS
)
1913 fc
->no_interrupt
= 1;
1914 else if (oh
.error
== -EAGAIN
)
1915 queue_interrupt(&fc
->iq
, req
);
1917 fuse_copy_finish(cs
);
1921 clear_bit(FR_SENT
, &req
->flags
);
1922 list_move(&req
->list
, &fpq
->io
);
1924 set_bit(FR_LOCKED
, &req
->flags
);
1925 spin_unlock(&fpq
->lock
);
1927 if (!req
->out
.page_replace
)
1930 err
= copy_out_args(cs
, &req
->out
, nbytes
);
1931 fuse_copy_finish(cs
);
1933 spin_lock(&fpq
->lock
);
1934 clear_bit(FR_LOCKED
, &req
->flags
);
1935 if (!fpq
->connected
)
1938 req
->out
.h
.error
= -EIO
;
1939 if (!test_bit(FR_PRIVATE
, &req
->flags
))
1940 list_del_init(&req
->list
);
1941 spin_unlock(&fpq
->lock
);
1943 request_end(fc
, req
);
1945 return err
? err
: nbytes
;
1948 spin_unlock(&fpq
->lock
);
1950 fuse_copy_finish(cs
);
1954 static ssize_t
fuse_dev_write(struct kiocb
*iocb
, struct iov_iter
*from
)
1956 struct fuse_copy_state cs
;
1957 struct fuse_conn
*fc
= fuse_get_conn(iocb
->ki_filp
);
1961 if (!iter_is_iovec(from
))
1964 fuse_copy_init(&cs
, 0, from
);
1966 return fuse_dev_do_write(fc
, &cs
, iov_iter_count(from
));
1969 static ssize_t
fuse_dev_splice_write(struct pipe_inode_info
*pipe
,
1970 struct file
*out
, loff_t
*ppos
,
1971 size_t len
, unsigned int flags
)
1975 struct pipe_buffer
*bufs
;
1976 struct fuse_copy_state cs
;
1977 struct fuse_conn
*fc
;
1981 fc
= fuse_get_conn(out
);
1985 bufs
= kmalloc(pipe
->buffers
* sizeof(struct pipe_buffer
), GFP_KERNEL
);
1992 for (idx
= 0; idx
< pipe
->nrbufs
&& rem
< len
; idx
++)
1993 rem
+= pipe
->bufs
[(pipe
->curbuf
+ idx
) & (pipe
->buffers
- 1)].len
;
2003 struct pipe_buffer
*ibuf
;
2004 struct pipe_buffer
*obuf
;
2006 BUG_ON(nbuf
>= pipe
->buffers
);
2007 BUG_ON(!pipe
->nrbufs
);
2008 ibuf
= &pipe
->bufs
[pipe
->curbuf
];
2011 if (rem
>= ibuf
->len
) {
2014 pipe
->curbuf
= (pipe
->curbuf
+ 1) & (pipe
->buffers
- 1);
2017 ibuf
->ops
->get(pipe
, ibuf
);
2019 obuf
->flags
&= ~PIPE_BUF_FLAG_GIFT
;
2021 ibuf
->offset
+= obuf
->len
;
2022 ibuf
->len
-= obuf
->len
;
2029 fuse_copy_init(&cs
, 0, NULL
);
2034 if (flags
& SPLICE_F_MOVE
)
2037 ret
= fuse_dev_do_write(fc
, &cs
, len
);
2039 for (idx
= 0; idx
< nbuf
; idx
++) {
2040 struct pipe_buffer
*buf
= &bufs
[idx
];
2041 buf
->ops
->release(pipe
, buf
);
2048 static unsigned fuse_dev_poll(struct file
*file
, poll_table
*wait
)
2050 unsigned mask
= POLLOUT
| POLLWRNORM
;
2051 struct fuse_iqueue
*fiq
;
2052 struct fuse_conn
*fc
= fuse_get_conn(file
);
2057 poll_wait(file
, &fiq
->waitq
, wait
);
2059 spin_lock(&fiq
->waitq
.lock
);
2060 if (!fiq
->connected
)
2062 else if (request_pending(fiq
))
2063 mask
|= POLLIN
| POLLRDNORM
;
2064 spin_unlock(&fiq
->waitq
.lock
);
2070 * Abort all requests on the given list (pending or processing)
2072 * This function releases and reacquires fc->lock
2074 static void end_requests(struct fuse_conn
*fc
, struct list_head
*head
)
2076 while (!list_empty(head
)) {
2077 struct fuse_req
*req
;
2078 req
= list_entry(head
->next
, struct fuse_req
, list
);
2079 req
->out
.h
.error
= -ECONNABORTED
;
2080 clear_bit(FR_PENDING
, &req
->flags
);
2081 clear_bit(FR_SENT
, &req
->flags
);
2082 list_del_init(&req
->list
);
2083 request_end(fc
, req
);
2087 static void end_polls(struct fuse_conn
*fc
)
2091 p
= rb_first(&fc
->polled_files
);
2094 struct fuse_file
*ff
;
2095 ff
= rb_entry(p
, struct fuse_file
, polled_node
);
2096 wake_up_interruptible_all(&ff
->poll_wait
);
2103 * Abort all requests.
2105 * Emergency exit in case of a malicious or accidental deadlock, or just a hung
2108 * The same effect is usually achievable through killing the filesystem daemon
2109 * and all users of the filesystem. The exception is the combination of an
2110 * asynchronous request and the tricky deadlock (see
2111 * Documentation/filesystems/fuse.txt).
2113 * Aborting requests under I/O goes as follows: 1: Separate out unlocked
2114 * requests, they should be finished off immediately. Locked requests will be
2115 * finished after unlock; see unlock_request(). 2: Finish off the unlocked
2116 * requests. It is possible that some request will finish before we can. This
2117 * is OK, the request will in that case be removed from the list before we touch
2120 void fuse_abort_conn(struct fuse_conn
*fc
)
2122 struct fuse_iqueue
*fiq
= &fc
->iq
;
2123 struct fuse_pqueue
*fpq
= &fc
->pq
;
2125 spin_lock(&fc
->lock
);
2126 if (fc
->connected
) {
2127 struct fuse_req
*req
, *next
;
2133 fuse_set_initialized(fc
);
2134 spin_lock(&fpq
->lock
);
2136 list_for_each_entry_safe(req
, next
, &fpq
->io
, list
) {
2137 req
->out
.h
.error
= -ECONNABORTED
;
2138 spin_lock(&req
->waitq
.lock
);
2139 set_bit(FR_ABORTED
, &req
->flags
);
2140 if (!test_bit(FR_LOCKED
, &req
->flags
)) {
2141 set_bit(FR_PRIVATE
, &req
->flags
);
2142 list_move(&req
->list
, &to_end1
);
2144 spin_unlock(&req
->waitq
.lock
);
2146 list_splice_init(&fpq
->processing
, &to_end2
);
2147 spin_unlock(&fpq
->lock
);
2148 fc
->max_background
= UINT_MAX
;
2151 spin_lock(&fiq
->waitq
.lock
);
2153 list_splice_init(&fiq
->pending
, &to_end2
);
2154 while (forget_pending(fiq
))
2155 kfree(dequeue_forget(fiq
, 1, NULL
));
2156 wake_up_all_locked(&fiq
->waitq
);
2157 spin_unlock(&fiq
->waitq
.lock
);
2158 kill_fasync(&fiq
->fasync
, SIGIO
, POLL_IN
);
2160 wake_up_all(&fc
->blocked_waitq
);
2161 spin_unlock(&fc
->lock
);
2163 while (!list_empty(&to_end1
)) {
2164 req
= list_first_entry(&to_end1
, struct fuse_req
, list
);
2165 __fuse_get_request(req
);
2166 list_del_init(&req
->list
);
2167 request_end(fc
, req
);
2169 end_requests(fc
, &to_end2
);
2171 spin_unlock(&fc
->lock
);
2174 EXPORT_SYMBOL_GPL(fuse_abort_conn
);
2176 int fuse_dev_release(struct inode
*inode
, struct file
*file
)
2178 struct fuse_conn
*fc
= fuse_get_conn(file
);
2180 WARN_ON(!list_empty(&fc
->pq
.io
));
2181 WARN_ON(fc
->iq
.fasync
!= NULL
);
2182 fuse_abort_conn(fc
);
2188 EXPORT_SYMBOL_GPL(fuse_dev_release
);
2190 static int fuse_dev_fasync(int fd
, struct file
*file
, int on
)
2192 struct fuse_conn
*fc
= fuse_get_conn(file
);
2196 /* No locking - fasync_helper does its own locking */
2197 return fasync_helper(fd
, file
, on
, &fc
->iq
.fasync
);
2200 static int fuse_device_clone(struct fuse_conn
*fc
, struct file
*new)
2202 if (new->private_data
)
2205 new->private_data
= fuse_conn_get(fc
);
2210 static long fuse_dev_ioctl(struct file
*file
, unsigned int cmd
,
2215 if (cmd
== FUSE_DEV_IOC_CLONE
) {
2219 if (!get_user(oldfd
, (__u32 __user
*) arg
)) {
2220 struct file
*old
= fget(oldfd
);
2224 struct fuse_conn
*fc
= fuse_get_conn(old
);
2227 mutex_lock(&fuse_mutex
);
2228 err
= fuse_device_clone(fc
, file
);
2229 mutex_unlock(&fuse_mutex
);
2238 const struct file_operations fuse_dev_operations
= {
2239 .owner
= THIS_MODULE
,
2240 .open
= fuse_dev_open
,
2241 .llseek
= no_llseek
,
2242 .read_iter
= fuse_dev_read
,
2243 .splice_read
= fuse_dev_splice_read
,
2244 .write_iter
= fuse_dev_write
,
2245 .splice_write
= fuse_dev_splice_write
,
2246 .poll
= fuse_dev_poll
,
2247 .release
= fuse_dev_release
,
2248 .fasync
= fuse_dev_fasync
,
2249 .unlocked_ioctl
= fuse_dev_ioctl
,
2250 .compat_ioctl
= fuse_dev_ioctl
,
2252 EXPORT_SYMBOL_GPL(fuse_dev_operations
);
2254 static struct miscdevice fuse_miscdevice
= {
2255 .minor
= FUSE_MINOR
,
2257 .fops
= &fuse_dev_operations
,
2260 int __init
fuse_dev_init(void)
2263 fuse_req_cachep
= kmem_cache_create("fuse_request",
2264 sizeof(struct fuse_req
),
2266 if (!fuse_req_cachep
)
2269 err
= misc_register(&fuse_miscdevice
);
2271 goto out_cache_clean
;
2276 kmem_cache_destroy(fuse_req_cachep
);
2281 void fuse_dev_cleanup(void)
2283 misc_deregister(&fuse_miscdevice
);
2284 kmem_cache_destroy(fuse_req_cachep
);