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1/*
2 FUSE: Filesystem in Userspace
3 Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu>
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/pagemap.h>
12#include <linux/slab.h>
13#include <linux/kernel.h>
14#include <linux/sched.h>
15#include <linux/module.h>
16#include <linux/compat.h>
17#include <linux/swap.h>
18
19static const struct file_operations fuse_direct_io_file_operations;
20
21static int fuse_send_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
22 int opcode, struct fuse_open_out *outargp)
23{
24 struct fuse_open_in inarg;
25 struct fuse_req *req;
26 int err;
27
28 req = fuse_get_req(fc);
29 if (IS_ERR(req))
30 return PTR_ERR(req);
31
32 memset(&inarg, 0, sizeof(inarg));
33 inarg.flags = file->f_flags & ~(O_CREAT | O_EXCL | O_NOCTTY);
34 if (!fc->atomic_o_trunc)
35 inarg.flags &= ~O_TRUNC;
36 req->in.h.opcode = opcode;
37 req->in.h.nodeid = nodeid;
38 req->in.numargs = 1;
39 req->in.args[0].size = sizeof(inarg);
40 req->in.args[0].value = &inarg;
41 req->out.numargs = 1;
42 req->out.args[0].size = sizeof(*outargp);
43 req->out.args[0].value = outargp;
44 fuse_request_send(fc, req);
45 err = req->out.h.error;
46 fuse_put_request(fc, req);
47
48 return err;
49}
50
51struct fuse_file *fuse_file_alloc(struct fuse_conn *fc)
52{
53 struct fuse_file *ff;
54
55 ff = kmalloc(sizeof(struct fuse_file), GFP_KERNEL);
56 if (unlikely(!ff))
57 return NULL;
58
59 ff->fc = fc;
60 ff->reserved_req = fuse_request_alloc();
61 if (unlikely(!ff->reserved_req)) {
62 kfree(ff);
63 return NULL;
64 }
65
66 INIT_LIST_HEAD(&ff->write_entry);
67 atomic_set(&ff->count, 0);
68 RB_CLEAR_NODE(&ff->polled_node);
69 init_waitqueue_head(&ff->poll_wait);
70
71 spin_lock(&fc->lock);
72 ff->kh = ++fc->khctr;
73 spin_unlock(&fc->lock);
74
75 return ff;
76}
77
78void fuse_file_free(struct fuse_file *ff)
79{
80 fuse_request_free(ff->reserved_req);
81 kfree(ff);
82}
83
84struct fuse_file *fuse_file_get(struct fuse_file *ff)
85{
86 atomic_inc(&ff->count);
87 return ff;
88}
89
90static void fuse_release_async(struct work_struct *work)
91{
92 struct fuse_req *req;
93 struct fuse_conn *fc;
94 struct path path;
95
96 req = container_of(work, struct fuse_req, misc.release.work);
97 path = req->misc.release.path;
98 fc = get_fuse_conn(path.dentry->d_inode);
99
100 fuse_put_request(fc, req);
101 path_put(&path);
102}
103
104static void fuse_release_end(struct fuse_conn *fc, struct fuse_req *req)
105{
106 if (fc->destroy_req) {
107 /*
108 * If this is a fuseblk mount, then it's possible that
109 * releasing the path will result in releasing the
110 * super block and sending the DESTROY request. If
111 * the server is single threaded, this would hang.
112 * For this reason do the path_put() in a separate
113 * thread.
114 */
115 atomic_inc(&req->count);
116 INIT_WORK(&req->misc.release.work, fuse_release_async);
117 schedule_work(&req->misc.release.work);
118 } else {
119 path_put(&req->misc.release.path);
120 }
121}
122
123static void fuse_file_put(struct fuse_file *ff, bool sync)
124{
125 if (atomic_dec_and_test(&ff->count)) {
126 struct fuse_req *req = ff->reserved_req;
127
128 if (sync) {
129 fuse_request_send(ff->fc, req);
130 path_put(&req->misc.release.path);
131 fuse_put_request(ff->fc, req);
132 } else {
133 req->end = fuse_release_end;
134 fuse_request_send_background(ff->fc, req);
135 }
136 kfree(ff);
137 }
138}
139
140int fuse_do_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
141 bool isdir)
142{
143 struct fuse_open_out outarg;
144 struct fuse_file *ff;
145 int err;
146 int opcode = isdir ? FUSE_OPENDIR : FUSE_OPEN;
147
148 ff = fuse_file_alloc(fc);
149 if (!ff)
150 return -ENOMEM;
151
152 err = fuse_send_open(fc, nodeid, file, opcode, &outarg);
153 if (err) {
154 fuse_file_free(ff);
155 return err;
156 }
157
158 if (isdir)
159 outarg.open_flags &= ~FOPEN_DIRECT_IO;
160
161 ff->fh = outarg.fh;
162 ff->nodeid = nodeid;
163 ff->open_flags = outarg.open_flags;
164 file->private_data = fuse_file_get(ff);
165
166 return 0;
167}
168EXPORT_SYMBOL_GPL(fuse_do_open);
169
170void fuse_finish_open(struct inode *inode, struct file *file)
171{
172 struct fuse_file *ff = file->private_data;
173 struct fuse_conn *fc = get_fuse_conn(inode);
174
175 if (ff->open_flags & FOPEN_DIRECT_IO)
176 file->f_op = &fuse_direct_io_file_operations;
177 if (!(ff->open_flags & FOPEN_KEEP_CACHE))
178 invalidate_inode_pages2(inode->i_mapping);
179 if (ff->open_flags & FOPEN_NONSEEKABLE)
180 nonseekable_open(inode, file);
181 if (fc->atomic_o_trunc && (file->f_flags & O_TRUNC)) {
182 struct fuse_inode *fi = get_fuse_inode(inode);
183
184 spin_lock(&fc->lock);
185 fi->attr_version = ++fc->attr_version;
186 i_size_write(inode, 0);
187 spin_unlock(&fc->lock);
188 fuse_invalidate_attr(inode);
189 }
190}
191
192int fuse_open_common(struct inode *inode, struct file *file, bool isdir)
193{
194 struct fuse_conn *fc = get_fuse_conn(inode);
195 int err;
196
197 err = generic_file_open(inode, file);
198 if (err)
199 return err;
200
201 err = fuse_do_open(fc, get_node_id(inode), file, isdir);
202 if (err)
203 return err;
204
205 fuse_finish_open(inode, file);
206
207 return 0;
208}
209
210static void fuse_prepare_release(struct fuse_file *ff, int flags, int opcode)
211{
212 struct fuse_conn *fc = ff->fc;
213 struct fuse_req *req = ff->reserved_req;
214 struct fuse_release_in *inarg = &req->misc.release.in;
215
216 spin_lock(&fc->lock);
217 list_del(&ff->write_entry);
218 if (!RB_EMPTY_NODE(&ff->polled_node))
219 rb_erase(&ff->polled_node, &fc->polled_files);
220 spin_unlock(&fc->lock);
221
222 wake_up_interruptible_all(&ff->poll_wait);
223
224 inarg->fh = ff->fh;
225 inarg->flags = flags;
226 req->in.h.opcode = opcode;
227 req->in.h.nodeid = ff->nodeid;
228 req->in.numargs = 1;
229 req->in.args[0].size = sizeof(struct fuse_release_in);
230 req->in.args[0].value = inarg;
231}
232
233void fuse_release_common(struct file *file, int opcode)
234{
235 struct fuse_file *ff;
236 struct fuse_req *req;
237
238 ff = file->private_data;
239 if (unlikely(!ff))
240 return;
241
242 req = ff->reserved_req;
243 fuse_prepare_release(ff, file->f_flags, opcode);
244
245 if (ff->flock) {
246 struct fuse_release_in *inarg = &req->misc.release.in;
247 inarg->release_flags |= FUSE_RELEASE_FLOCK_UNLOCK;
248 inarg->lock_owner = fuse_lock_owner_id(ff->fc,
249 (fl_owner_t) file);
250 }
251 /* Hold vfsmount and dentry until release is finished */
252 path_get(&file->f_path);
253 req->misc.release.path = file->f_path;
254
255 /*
256 * Normally this will send the RELEASE request, however if
257 * some asynchronous READ or WRITE requests are outstanding,
258 * the sending will be delayed.
259 *
260 * Make the release synchronous if this is a fuseblk mount,
261 * synchronous RELEASE is allowed (and desirable) in this case
262 * because the server can be trusted not to screw up.
263 */
264 fuse_file_put(ff, ff->fc->destroy_req != NULL);
265}
266
267static int fuse_open(struct inode *inode, struct file *file)
268{
269 return fuse_open_common(inode, file, false);
270}
271
272static int fuse_release(struct inode *inode, struct file *file)
273{
274 fuse_release_common(file, FUSE_RELEASE);
275
276 /* return value is ignored by VFS */
277 return 0;
278}
279
280void fuse_sync_release(struct fuse_file *ff, int flags)
281{
282 WARN_ON(atomic_read(&ff->count) > 1);
283 fuse_prepare_release(ff, flags, FUSE_RELEASE);
284 ff->reserved_req->force = 1;
285 fuse_request_send(ff->fc, ff->reserved_req);
286 fuse_put_request(ff->fc, ff->reserved_req);
287 kfree(ff);
288}
289EXPORT_SYMBOL_GPL(fuse_sync_release);
290
291/*
292 * Scramble the ID space with XTEA, so that the value of the files_struct
293 * pointer is not exposed to userspace.
294 */
295u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id)
296{
297 u32 *k = fc->scramble_key;
298 u64 v = (unsigned long) id;
299 u32 v0 = v;
300 u32 v1 = v >> 32;
301 u32 sum = 0;
302 int i;
303
304 for (i = 0; i < 32; i++) {
305 v0 += ((v1 << 4 ^ v1 >> 5) + v1) ^ (sum + k[sum & 3]);
306 sum += 0x9E3779B9;
307 v1 += ((v0 << 4 ^ v0 >> 5) + v0) ^ (sum + k[sum>>11 & 3]);
308 }
309
310 return (u64) v0 + ((u64) v1 << 32);
311}
312
313/*
314 * Check if page is under writeback
315 *
316 * This is currently done by walking the list of writepage requests
317 * for the inode, which can be pretty inefficient.
318 */
319static bool fuse_page_is_writeback(struct inode *inode, pgoff_t index)
320{
321 struct fuse_conn *fc = get_fuse_conn(inode);
322 struct fuse_inode *fi = get_fuse_inode(inode);
323 struct fuse_req *req;
324 bool found = false;
325
326 spin_lock(&fc->lock);
327 list_for_each_entry(req, &fi->writepages, writepages_entry) {
328 pgoff_t curr_index;
329
330 BUG_ON(req->inode != inode);
331 curr_index = req->misc.write.in.offset >> PAGE_CACHE_SHIFT;
332 if (curr_index == index) {
333 found = true;
334 break;
335 }
336 }
337 spin_unlock(&fc->lock);
338
339 return found;
340}
341
342/*
343 * Wait for page writeback to be completed.
344 *
345 * Since fuse doesn't rely on the VM writeback tracking, this has to
346 * use some other means.
347 */
348static int fuse_wait_on_page_writeback(struct inode *inode, pgoff_t index)
349{
350 struct fuse_inode *fi = get_fuse_inode(inode);
351
352 wait_event(fi->page_waitq, !fuse_page_is_writeback(inode, index));
353 return 0;
354}
355
356static int fuse_flush(struct file *file, fl_owner_t id)
357{
358 struct inode *inode = file->f_path.dentry->d_inode;
359 struct fuse_conn *fc = get_fuse_conn(inode);
360 struct fuse_file *ff = file->private_data;
361 struct fuse_req *req;
362 struct fuse_flush_in inarg;
363 int err;
364
365 if (is_bad_inode(inode))
366 return -EIO;
367
368 if (fc->no_flush)
369 return 0;
370
371 req = fuse_get_req_nofail(fc, file);
372 memset(&inarg, 0, sizeof(inarg));
373 inarg.fh = ff->fh;
374 inarg.lock_owner = fuse_lock_owner_id(fc, id);
375 req->in.h.opcode = FUSE_FLUSH;
376 req->in.h.nodeid = get_node_id(inode);
377 req->in.numargs = 1;
378 req->in.args[0].size = sizeof(inarg);
379 req->in.args[0].value = &inarg;
380 req->force = 1;
381 fuse_request_send(fc, req);
382 err = req->out.h.error;
383 fuse_put_request(fc, req);
384 if (err == -ENOSYS) {
385 fc->no_flush = 1;
386 err = 0;
387 }
388 return err;
389}
390
391/*
392 * Wait for all pending writepages on the inode to finish.
393 *
394 * This is currently done by blocking further writes with FUSE_NOWRITE
395 * and waiting for all sent writes to complete.
396 *
397 * This must be called under i_mutex, otherwise the FUSE_NOWRITE usage
398 * could conflict with truncation.
399 */
400static void fuse_sync_writes(struct inode *inode)
401{
402 fuse_set_nowrite(inode);
403 fuse_release_nowrite(inode);
404}
405
406int fuse_fsync_common(struct file *file, loff_t start, loff_t end,
407 int datasync, int isdir)
408{
409 struct inode *inode = file->f_mapping->host;
410 struct fuse_conn *fc = get_fuse_conn(inode);
411 struct fuse_file *ff = file->private_data;
412 struct fuse_req *req;
413 struct fuse_fsync_in inarg;
414 int err;
415
416 if (is_bad_inode(inode))
417 return -EIO;
418
419 err = filemap_write_and_wait_range(inode->i_mapping, start, end);
420 if (err)
421 return err;
422
423 if ((!isdir && fc->no_fsync) || (isdir && fc->no_fsyncdir))
424 return 0;
425
426 mutex_lock(&inode->i_mutex);
427
428 /*
429 * Start writeback against all dirty pages of the inode, then
430 * wait for all outstanding writes, before sending the FSYNC
431 * request.
432 */
433 err = write_inode_now(inode, 0);
434 if (err)
435 goto out;
436
437 fuse_sync_writes(inode);
438
439 req = fuse_get_req(fc);
440 if (IS_ERR(req)) {
441 err = PTR_ERR(req);
442 goto out;
443 }
444
445 memset(&inarg, 0, sizeof(inarg));
446 inarg.fh = ff->fh;
447 inarg.fsync_flags = datasync ? 1 : 0;
448 req->in.h.opcode = isdir ? FUSE_FSYNCDIR : FUSE_FSYNC;
449 req->in.h.nodeid = get_node_id(inode);
450 req->in.numargs = 1;
451 req->in.args[0].size = sizeof(inarg);
452 req->in.args[0].value = &inarg;
453 fuse_request_send(fc, req);
454 err = req->out.h.error;
455 fuse_put_request(fc, req);
456 if (err == -ENOSYS) {
457 if (isdir)
458 fc->no_fsyncdir = 1;
459 else
460 fc->no_fsync = 1;
461 err = 0;
462 }
463out:
464 mutex_unlock(&inode->i_mutex);
465 return err;
466}
467
468static int fuse_fsync(struct file *file, loff_t start, loff_t end,
469 int datasync)
470{
471 return fuse_fsync_common(file, start, end, datasync, 0);
472}
473
474void fuse_read_fill(struct fuse_req *req, struct file *file, loff_t pos,
475 size_t count, int opcode)
476{
477 struct fuse_read_in *inarg = &req->misc.read.in;
478 struct fuse_file *ff = file->private_data;
479
480 inarg->fh = ff->fh;
481 inarg->offset = pos;
482 inarg->size = count;
483 inarg->flags = file->f_flags;
484 req->in.h.opcode = opcode;
485 req->in.h.nodeid = ff->nodeid;
486 req->in.numargs = 1;
487 req->in.args[0].size = sizeof(struct fuse_read_in);
488 req->in.args[0].value = inarg;
489 req->out.argvar = 1;
490 req->out.numargs = 1;
491 req->out.args[0].size = count;
492}
493
494static size_t fuse_send_read(struct fuse_req *req, struct file *file,
495 loff_t pos, size_t count, fl_owner_t owner)
496{
497 struct fuse_file *ff = file->private_data;
498 struct fuse_conn *fc = ff->fc;
499
500 fuse_read_fill(req, file, pos, count, FUSE_READ);
501 if (owner != NULL) {
502 struct fuse_read_in *inarg = &req->misc.read.in;
503
504 inarg->read_flags |= FUSE_READ_LOCKOWNER;
505 inarg->lock_owner = fuse_lock_owner_id(fc, owner);
506 }
507 fuse_request_send(fc, req);
508 return req->out.args[0].size;
509}
510
511static void fuse_read_update_size(struct inode *inode, loff_t size,
512 u64 attr_ver)
513{
514 struct fuse_conn *fc = get_fuse_conn(inode);
515 struct fuse_inode *fi = get_fuse_inode(inode);
516
517 spin_lock(&fc->lock);
518 if (attr_ver == fi->attr_version && size < inode->i_size) {
519 fi->attr_version = ++fc->attr_version;
520 i_size_write(inode, size);
521 }
522 spin_unlock(&fc->lock);
523}
524
525static int fuse_readpage(struct file *file, struct page *page)
526{
527 struct inode *inode = page->mapping->host;
528 struct fuse_conn *fc = get_fuse_conn(inode);
529 struct fuse_req *req;
530 size_t num_read;
531 loff_t pos = page_offset(page);
532 size_t count = PAGE_CACHE_SIZE;
533 u64 attr_ver;
534 int err;
535
536 err = -EIO;
537 if (is_bad_inode(inode))
538 goto out;
539
540 /*
541 * Page writeback can extend beyond the lifetime of the
542 * page-cache page, so make sure we read a properly synced
543 * page.
544 */
545 fuse_wait_on_page_writeback(inode, page->index);
546
547 req = fuse_get_req(fc);
548 err = PTR_ERR(req);
549 if (IS_ERR(req))
550 goto out;
551
552 attr_ver = fuse_get_attr_version(fc);
553
554 req->out.page_zeroing = 1;
555 req->out.argpages = 1;
556 req->num_pages = 1;
557 req->pages[0] = page;
558 num_read = fuse_send_read(req, file, pos, count, NULL);
559 err = req->out.h.error;
560 fuse_put_request(fc, req);
561
562 if (!err) {
563 /*
564 * Short read means EOF. If file size is larger, truncate it
565 */
566 if (num_read < count)
567 fuse_read_update_size(inode, pos + num_read, attr_ver);
568
569 SetPageUptodate(page);
570 }
571
572 fuse_invalidate_attr(inode); /* atime changed */
573 out:
574 unlock_page(page);
575 return err;
576}
577
578static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req)
579{
580 int i;
581 size_t count = req->misc.read.in.size;
582 size_t num_read = req->out.args[0].size;
583 struct address_space *mapping = NULL;
584
585 for (i = 0; mapping == NULL && i < req->num_pages; i++)
586 mapping = req->pages[i]->mapping;
587
588 if (mapping) {
589 struct inode *inode = mapping->host;
590
591 /*
592 * Short read means EOF. If file size is larger, truncate it
593 */
594 if (!req->out.h.error && num_read < count) {
595 loff_t pos;
596
597 pos = page_offset(req->pages[0]) + num_read;
598 fuse_read_update_size(inode, pos,
599 req->misc.read.attr_ver);
600 }
601 fuse_invalidate_attr(inode); /* atime changed */
602 }
603
604 for (i = 0; i < req->num_pages; i++) {
605 struct page *page = req->pages[i];
606 if (!req->out.h.error)
607 SetPageUptodate(page);
608 else
609 SetPageError(page);
610 unlock_page(page);
611 page_cache_release(page);
612 }
613 if (req->ff)
614 fuse_file_put(req->ff, false);
615}
616
617static void fuse_send_readpages(struct fuse_req *req, struct file *file)
618{
619 struct fuse_file *ff = file->private_data;
620 struct fuse_conn *fc = ff->fc;
621 loff_t pos = page_offset(req->pages[0]);
622 size_t count = req->num_pages << PAGE_CACHE_SHIFT;
623
624 req->out.argpages = 1;
625 req->out.page_zeroing = 1;
626 req->out.page_replace = 1;
627 fuse_read_fill(req, file, pos, count, FUSE_READ);
628 req->misc.read.attr_ver = fuse_get_attr_version(fc);
629 if (fc->async_read) {
630 req->ff = fuse_file_get(ff);
631 req->end = fuse_readpages_end;
632 fuse_request_send_background(fc, req);
633 } else {
634 fuse_request_send(fc, req);
635 fuse_readpages_end(fc, req);
636 fuse_put_request(fc, req);
637 }
638}
639
640struct fuse_fill_data {
641 struct fuse_req *req;
642 struct file *file;
643 struct inode *inode;
644};
645
646static int fuse_readpages_fill(void *_data, struct page *page)
647{
648 struct fuse_fill_data *data = _data;
649 struct fuse_req *req = data->req;
650 struct inode *inode = data->inode;
651 struct fuse_conn *fc = get_fuse_conn(inode);
652
653 fuse_wait_on_page_writeback(inode, page->index);
654
655 if (req->num_pages &&
656 (req->num_pages == FUSE_MAX_PAGES_PER_REQ ||
657 (req->num_pages + 1) * PAGE_CACHE_SIZE > fc->max_read ||
658 req->pages[req->num_pages - 1]->index + 1 != page->index)) {
659 fuse_send_readpages(req, data->file);
660 data->req = req = fuse_get_req(fc);
661 if (IS_ERR(req)) {
662 unlock_page(page);
663 return PTR_ERR(req);
664 }
665 }
666 page_cache_get(page);
667 req->pages[req->num_pages] = page;
668 req->num_pages++;
669 return 0;
670}
671
672static int fuse_readpages(struct file *file, struct address_space *mapping,
673 struct list_head *pages, unsigned nr_pages)
674{
675 struct inode *inode = mapping->host;
676 struct fuse_conn *fc = get_fuse_conn(inode);
677 struct fuse_fill_data data;
678 int err;
679
680 err = -EIO;
681 if (is_bad_inode(inode))
682 goto out;
683
684 data.file = file;
685 data.inode = inode;
686 data.req = fuse_get_req(fc);
687 err = PTR_ERR(data.req);
688 if (IS_ERR(data.req))
689 goto out;
690
691 err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data);
692 if (!err) {
693 if (data.req->num_pages)
694 fuse_send_readpages(data.req, file);
695 else
696 fuse_put_request(fc, data.req);
697 }
698out:
699 return err;
700}
701
702static ssize_t fuse_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
703 unsigned long nr_segs, loff_t pos)
704{
705 struct inode *inode = iocb->ki_filp->f_mapping->host;
706
707 if (pos + iov_length(iov, nr_segs) > i_size_read(inode)) {
708 int err;
709 /*
710 * If trying to read past EOF, make sure the i_size
711 * attribute is up-to-date.
712 */
713 err = fuse_update_attributes(inode, NULL, iocb->ki_filp, NULL);
714 if (err)
715 return err;
716 }
717
718 return generic_file_aio_read(iocb, iov, nr_segs, pos);
719}
720
721static void fuse_write_fill(struct fuse_req *req, struct fuse_file *ff,
722 loff_t pos, size_t count)
723{
724 struct fuse_write_in *inarg = &req->misc.write.in;
725 struct fuse_write_out *outarg = &req->misc.write.out;
726
727 inarg->fh = ff->fh;
728 inarg->offset = pos;
729 inarg->size = count;
730 req->in.h.opcode = FUSE_WRITE;
731 req->in.h.nodeid = ff->nodeid;
732 req->in.numargs = 2;
733 if (ff->fc->minor < 9)
734 req->in.args[0].size = FUSE_COMPAT_WRITE_IN_SIZE;
735 else
736 req->in.args[0].size = sizeof(struct fuse_write_in);
737 req->in.args[0].value = inarg;
738 req->in.args[1].size = count;
739 req->out.numargs = 1;
740 req->out.args[0].size = sizeof(struct fuse_write_out);
741 req->out.args[0].value = outarg;
742}
743
744static size_t fuse_send_write(struct fuse_req *req, struct file *file,
745 loff_t pos, size_t count, fl_owner_t owner)
746{
747 struct fuse_file *ff = file->private_data;
748 struct fuse_conn *fc = ff->fc;
749 struct fuse_write_in *inarg = &req->misc.write.in;
750
751 fuse_write_fill(req, ff, pos, count);
752 inarg->flags = file->f_flags;
753 if (owner != NULL) {
754 inarg->write_flags |= FUSE_WRITE_LOCKOWNER;
755 inarg->lock_owner = fuse_lock_owner_id(fc, owner);
756 }
757 fuse_request_send(fc, req);
758 return req->misc.write.out.size;
759}
760
761void fuse_write_update_size(struct inode *inode, loff_t pos)
762{
763 struct fuse_conn *fc = get_fuse_conn(inode);
764 struct fuse_inode *fi = get_fuse_inode(inode);
765
766 spin_lock(&fc->lock);
767 fi->attr_version = ++fc->attr_version;
768 if (pos > inode->i_size)
769 i_size_write(inode, pos);
770 spin_unlock(&fc->lock);
771}
772
773static size_t fuse_send_write_pages(struct fuse_req *req, struct file *file,
774 struct inode *inode, loff_t pos,
775 size_t count)
776{
777 size_t res;
778 unsigned offset;
779 unsigned i;
780
781 for (i = 0; i < req->num_pages; i++)
782 fuse_wait_on_page_writeback(inode, req->pages[i]->index);
783
784 res = fuse_send_write(req, file, pos, count, NULL);
785
786 offset = req->page_offset;
787 count = res;
788 for (i = 0; i < req->num_pages; i++) {
789 struct page *page = req->pages[i];
790
791 if (!req->out.h.error && !offset && count >= PAGE_CACHE_SIZE)
792 SetPageUptodate(page);
793
794 if (count > PAGE_CACHE_SIZE - offset)
795 count -= PAGE_CACHE_SIZE - offset;
796 else
797 count = 0;
798 offset = 0;
799
800 unlock_page(page);
801 page_cache_release(page);
802 }
803
804 return res;
805}
806
807static ssize_t fuse_fill_write_pages(struct fuse_req *req,
808 struct address_space *mapping,
809 struct iov_iter *ii, loff_t pos)
810{
811 struct fuse_conn *fc = get_fuse_conn(mapping->host);
812 unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
813 size_t count = 0;
814 int err;
815
816 req->in.argpages = 1;
817 req->page_offset = offset;
818
819 do {
820 size_t tmp;
821 struct page *page;
822 pgoff_t index = pos >> PAGE_CACHE_SHIFT;
823 size_t bytes = min_t(size_t, PAGE_CACHE_SIZE - offset,
824 iov_iter_count(ii));
825
826 bytes = min_t(size_t, bytes, fc->max_write - count);
827
828 again:
829 err = -EFAULT;
830 if (iov_iter_fault_in_readable(ii, bytes))
831 break;
832
833 err = -ENOMEM;
834 page = grab_cache_page_write_begin(mapping, index, 0);
835 if (!page)
836 break;
837
838 if (mapping_writably_mapped(mapping))
839 flush_dcache_page(page);
840
841 pagefault_disable();
842 tmp = iov_iter_copy_from_user_atomic(page, ii, offset, bytes);
843 pagefault_enable();
844 flush_dcache_page(page);
845
846 mark_page_accessed(page);
847
848 if (!tmp) {
849 unlock_page(page);
850 page_cache_release(page);
851 bytes = min(bytes, iov_iter_single_seg_count(ii));
852 goto again;
853 }
854
855 err = 0;
856 req->pages[req->num_pages] = page;
857 req->num_pages++;
858
859 iov_iter_advance(ii, tmp);
860 count += tmp;
861 pos += tmp;
862 offset += tmp;
863 if (offset == PAGE_CACHE_SIZE)
864 offset = 0;
865
866 if (!fc->big_writes)
867 break;
868 } while (iov_iter_count(ii) && count < fc->max_write &&
869 req->num_pages < FUSE_MAX_PAGES_PER_REQ && offset == 0);
870
871 return count > 0 ? count : err;
872}
873
874static ssize_t fuse_perform_write(struct file *file,
875 struct address_space *mapping,
876 struct iov_iter *ii, loff_t pos)
877{
878 struct inode *inode = mapping->host;
879 struct fuse_conn *fc = get_fuse_conn(inode);
880 int err = 0;
881 ssize_t res = 0;
882
883 if (is_bad_inode(inode))
884 return -EIO;
885
886 do {
887 struct fuse_req *req;
888 ssize_t count;
889
890 req = fuse_get_req(fc);
891 if (IS_ERR(req)) {
892 err = PTR_ERR(req);
893 break;
894 }
895
896 count = fuse_fill_write_pages(req, mapping, ii, pos);
897 if (count <= 0) {
898 err = count;
899 } else {
900 size_t num_written;
901
902 num_written = fuse_send_write_pages(req, file, inode,
903 pos, count);
904 err = req->out.h.error;
905 if (!err) {
906 res += num_written;
907 pos += num_written;
908
909 /* break out of the loop on short write */
910 if (num_written != count)
911 err = -EIO;
912 }
913 }
914 fuse_put_request(fc, req);
915 } while (!err && iov_iter_count(ii));
916
917 if (res > 0)
918 fuse_write_update_size(inode, pos);
919
920 fuse_invalidate_attr(inode);
921
922 return res > 0 ? res : err;
923}
924
925static ssize_t fuse_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
926 unsigned long nr_segs, loff_t pos)
927{
928 struct file *file = iocb->ki_filp;
929 struct address_space *mapping = file->f_mapping;
930 size_t count = 0;
931 size_t ocount = 0;
932 ssize_t written = 0;
933 ssize_t written_buffered = 0;
934 struct inode *inode = mapping->host;
935 ssize_t err;
936 struct iov_iter i;
937 loff_t endbyte = 0;
938
939 WARN_ON(iocb->ki_pos != pos);
940
941 ocount = 0;
942 err = generic_segment_checks(iov, &nr_segs, &ocount, VERIFY_READ);
943 if (err)
944 return err;
945
946 count = ocount;
947
948 mutex_lock(&inode->i_mutex);
949 vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
950
951 /* We can write back this queue in page reclaim */
952 current->backing_dev_info = mapping->backing_dev_info;
953
954 err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
955 if (err)
956 goto out;
957
958 if (count == 0)
959 goto out;
960
961 err = file_remove_suid(file);
962 if (err)
963 goto out;
964
965 err = file_update_time(file);
966 if (err)
967 goto out;
968
969 if (file->f_flags & O_DIRECT) {
970 written = generic_file_direct_write(iocb, iov, &nr_segs,
971 pos, &iocb->ki_pos,
972 count, ocount);
973 if (written < 0 || written == count)
974 goto out;
975
976 pos += written;
977 count -= written;
978
979 iov_iter_init(&i, iov, nr_segs, count, written);
980 written_buffered = fuse_perform_write(file, mapping, &i, pos);
981 if (written_buffered < 0) {
982 err = written_buffered;
983 goto out;
984 }
985 endbyte = pos + written_buffered - 1;
986
987 err = filemap_write_and_wait_range(file->f_mapping, pos,
988 endbyte);
989 if (err)
990 goto out;
991
992 invalidate_mapping_pages(file->f_mapping,
993 pos >> PAGE_CACHE_SHIFT,
994 endbyte >> PAGE_CACHE_SHIFT);
995
996 written += written_buffered;
997 iocb->ki_pos = pos + written_buffered;
998 } else {
999 iov_iter_init(&i, iov, nr_segs, count, 0);
1000 written = fuse_perform_write(file, mapping, &i, pos);
1001 if (written >= 0)
1002 iocb->ki_pos = pos + written;
1003 }
1004out:
1005 current->backing_dev_info = NULL;
1006 mutex_unlock(&inode->i_mutex);
1007
1008 return written ? written : err;
1009}
1010
1011static void fuse_release_user_pages(struct fuse_req *req, int write)
1012{
1013 unsigned i;
1014
1015 for (i = 0; i < req->num_pages; i++) {
1016 struct page *page = req->pages[i];
1017 if (write)
1018 set_page_dirty_lock(page);
1019 put_page(page);
1020 }
1021}
1022
1023static int fuse_get_user_pages(struct fuse_req *req, const char __user *buf,
1024 size_t *nbytesp, int write)
1025{
1026 size_t nbytes = *nbytesp;
1027 unsigned long user_addr = (unsigned long) buf;
1028 unsigned offset = user_addr & ~PAGE_MASK;
1029 int npages;
1030
1031 /* Special case for kernel I/O: can copy directly into the buffer */
1032 if (segment_eq(get_fs(), KERNEL_DS)) {
1033 if (write)
1034 req->in.args[1].value = (void *) user_addr;
1035 else
1036 req->out.args[0].value = (void *) user_addr;
1037
1038 return 0;
1039 }
1040
1041 nbytes = min_t(size_t, nbytes, FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT);
1042 npages = (nbytes + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
1043 npages = clamp(npages, 1, FUSE_MAX_PAGES_PER_REQ);
1044 npages = get_user_pages_fast(user_addr, npages, !write, req->pages);
1045 if (npages < 0)
1046 return npages;
1047
1048 req->num_pages = npages;
1049 req->page_offset = offset;
1050
1051 if (write)
1052 req->in.argpages = 1;
1053 else
1054 req->out.argpages = 1;
1055
1056 nbytes = (req->num_pages << PAGE_SHIFT) - req->page_offset;
1057 *nbytesp = min(*nbytesp, nbytes);
1058
1059 return 0;
1060}
1061
1062ssize_t fuse_direct_io(struct file *file, const char __user *buf,
1063 size_t count, loff_t *ppos, int write)
1064{
1065 struct fuse_file *ff = file->private_data;
1066 struct fuse_conn *fc = ff->fc;
1067 size_t nmax = write ? fc->max_write : fc->max_read;
1068 loff_t pos = *ppos;
1069 ssize_t res = 0;
1070 struct fuse_req *req;
1071
1072 req = fuse_get_req(fc);
1073 if (IS_ERR(req))
1074 return PTR_ERR(req);
1075
1076 while (count) {
1077 size_t nres;
1078 fl_owner_t owner = current->files;
1079 size_t nbytes = min(count, nmax);
1080 int err = fuse_get_user_pages(req, buf, &nbytes, write);
1081 if (err) {
1082 res = err;
1083 break;
1084 }
1085
1086 if (write)
1087 nres = fuse_send_write(req, file, pos, nbytes, owner);
1088 else
1089 nres = fuse_send_read(req, file, pos, nbytes, owner);
1090
1091 fuse_release_user_pages(req, !write);
1092 if (req->out.h.error) {
1093 if (!res)
1094 res = req->out.h.error;
1095 break;
1096 } else if (nres > nbytes) {
1097 res = -EIO;
1098 break;
1099 }
1100 count -= nres;
1101 res += nres;
1102 pos += nres;
1103 buf += nres;
1104 if (nres != nbytes)
1105 break;
1106 if (count) {
1107 fuse_put_request(fc, req);
1108 req = fuse_get_req(fc);
1109 if (IS_ERR(req))
1110 break;
1111 }
1112 }
1113 if (!IS_ERR(req))
1114 fuse_put_request(fc, req);
1115 if (res > 0)
1116 *ppos = pos;
1117
1118 return res;
1119}
1120EXPORT_SYMBOL_GPL(fuse_direct_io);
1121
1122static ssize_t fuse_direct_read(struct file *file, char __user *buf,
1123 size_t count, loff_t *ppos)
1124{
1125 ssize_t res;
1126 struct inode *inode = file->f_path.dentry->d_inode;
1127
1128 if (is_bad_inode(inode))
1129 return -EIO;
1130
1131 res = fuse_direct_io(file, buf, count, ppos, 0);
1132
1133 fuse_invalidate_attr(inode);
1134
1135 return res;
1136}
1137
1138static ssize_t __fuse_direct_write(struct file *file, const char __user *buf,
1139 size_t count, loff_t *ppos)
1140{
1141 struct inode *inode = file->f_path.dentry->d_inode;
1142 ssize_t res;
1143
1144 res = generic_write_checks(file, ppos, &count, 0);
1145 if (!res) {
1146 res = fuse_direct_io(file, buf, count, ppos, 1);
1147 if (res > 0)
1148 fuse_write_update_size(inode, *ppos);
1149 }
1150
1151 fuse_invalidate_attr(inode);
1152
1153 return res;
1154}
1155
1156static ssize_t fuse_direct_write(struct file *file, const char __user *buf,
1157 size_t count, loff_t *ppos)
1158{
1159 struct inode *inode = file->f_path.dentry->d_inode;
1160 ssize_t res;
1161
1162 if (is_bad_inode(inode))
1163 return -EIO;
1164
1165 /* Don't allow parallel writes to the same file */
1166 mutex_lock(&inode->i_mutex);
1167 res = __fuse_direct_write(file, buf, count, ppos);
1168 mutex_unlock(&inode->i_mutex);
1169
1170 return res;
1171}
1172
1173static void fuse_writepage_free(struct fuse_conn *fc, struct fuse_req *req)
1174{
1175 __free_page(req->pages[0]);
1176 fuse_file_put(req->ff, false);
1177}
1178
1179static void fuse_writepage_finish(struct fuse_conn *fc, struct fuse_req *req)
1180{
1181 struct inode *inode = req->inode;
1182 struct fuse_inode *fi = get_fuse_inode(inode);
1183 struct backing_dev_info *bdi = inode->i_mapping->backing_dev_info;
1184
1185 list_del(&req->writepages_entry);
1186 dec_bdi_stat(bdi, BDI_WRITEBACK);
1187 dec_zone_page_state(req->pages[0], NR_WRITEBACK_TEMP);
1188 bdi_writeout_inc(bdi);
1189 wake_up(&fi->page_waitq);
1190}
1191
1192/* Called under fc->lock, may release and reacquire it */
1193static void fuse_send_writepage(struct fuse_conn *fc, struct fuse_req *req)
1194__releases(fc->lock)
1195__acquires(fc->lock)
1196{
1197 struct fuse_inode *fi = get_fuse_inode(req->inode);
1198 loff_t size = i_size_read(req->inode);
1199 struct fuse_write_in *inarg = &req->misc.write.in;
1200
1201 if (!fc->connected)
1202 goto out_free;
1203
1204 if (inarg->offset + PAGE_CACHE_SIZE <= size) {
1205 inarg->size = PAGE_CACHE_SIZE;
1206 } else if (inarg->offset < size) {
1207 inarg->size = size & (PAGE_CACHE_SIZE - 1);
1208 } else {
1209 /* Got truncated off completely */
1210 goto out_free;
1211 }
1212
1213 req->in.args[1].size = inarg->size;
1214 fi->writectr++;
1215 fuse_request_send_background_locked(fc, req);
1216 return;
1217
1218 out_free:
1219 fuse_writepage_finish(fc, req);
1220 spin_unlock(&fc->lock);
1221 fuse_writepage_free(fc, req);
1222 fuse_put_request(fc, req);
1223 spin_lock(&fc->lock);
1224}
1225
1226/*
1227 * If fi->writectr is positive (no truncate or fsync going on) send
1228 * all queued writepage requests.
1229 *
1230 * Called with fc->lock
1231 */
1232void fuse_flush_writepages(struct inode *inode)
1233__releases(fc->lock)
1234__acquires(fc->lock)
1235{
1236 struct fuse_conn *fc = get_fuse_conn(inode);
1237 struct fuse_inode *fi = get_fuse_inode(inode);
1238 struct fuse_req *req;
1239
1240 while (fi->writectr >= 0 && !list_empty(&fi->queued_writes)) {
1241 req = list_entry(fi->queued_writes.next, struct fuse_req, list);
1242 list_del_init(&req->list);
1243 fuse_send_writepage(fc, req);
1244 }
1245}
1246
1247static void fuse_writepage_end(struct fuse_conn *fc, struct fuse_req *req)
1248{
1249 struct inode *inode = req->inode;
1250 struct fuse_inode *fi = get_fuse_inode(inode);
1251
1252 mapping_set_error(inode->i_mapping, req->out.h.error);
1253 spin_lock(&fc->lock);
1254 fi->writectr--;
1255 fuse_writepage_finish(fc, req);
1256 spin_unlock(&fc->lock);
1257 fuse_writepage_free(fc, req);
1258}
1259
1260static int fuse_writepage_locked(struct page *page)
1261{
1262 struct address_space *mapping = page->mapping;
1263 struct inode *inode = mapping->host;
1264 struct fuse_conn *fc = get_fuse_conn(inode);
1265 struct fuse_inode *fi = get_fuse_inode(inode);
1266 struct fuse_req *req;
1267 struct fuse_file *ff;
1268 struct page *tmp_page;
1269
1270 set_page_writeback(page);
1271
1272 req = fuse_request_alloc_nofs();
1273 if (!req)
1274 goto err;
1275
1276 tmp_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM);
1277 if (!tmp_page)
1278 goto err_free;
1279
1280 spin_lock(&fc->lock);
1281 BUG_ON(list_empty(&fi->write_files));
1282 ff = list_entry(fi->write_files.next, struct fuse_file, write_entry);
1283 req->ff = fuse_file_get(ff);
1284 spin_unlock(&fc->lock);
1285
1286 fuse_write_fill(req, ff, page_offset(page), 0);
1287
1288 copy_highpage(tmp_page, page);
1289 req->misc.write.in.write_flags |= FUSE_WRITE_CACHE;
1290 req->in.argpages = 1;
1291 req->num_pages = 1;
1292 req->pages[0] = tmp_page;
1293 req->page_offset = 0;
1294 req->end = fuse_writepage_end;
1295 req->inode = inode;
1296
1297 inc_bdi_stat(mapping->backing_dev_info, BDI_WRITEBACK);
1298 inc_zone_page_state(tmp_page, NR_WRITEBACK_TEMP);
1299 end_page_writeback(page);
1300
1301 spin_lock(&fc->lock);
1302 list_add(&req->writepages_entry, &fi->writepages);
1303 list_add_tail(&req->list, &fi->queued_writes);
1304 fuse_flush_writepages(inode);
1305 spin_unlock(&fc->lock);
1306
1307 return 0;
1308
1309err_free:
1310 fuse_request_free(req);
1311err:
1312 end_page_writeback(page);
1313 return -ENOMEM;
1314}
1315
1316static int fuse_writepage(struct page *page, struct writeback_control *wbc)
1317{
1318 int err;
1319
1320 err = fuse_writepage_locked(page);
1321 unlock_page(page);
1322
1323 return err;
1324}
1325
1326static int fuse_launder_page(struct page *page)
1327{
1328 int err = 0;
1329 if (clear_page_dirty_for_io(page)) {
1330 struct inode *inode = page->mapping->host;
1331 err = fuse_writepage_locked(page);
1332 if (!err)
1333 fuse_wait_on_page_writeback(inode, page->index);
1334 }
1335 return err;
1336}
1337
1338/*
1339 * Write back dirty pages now, because there may not be any suitable
1340 * open files later
1341 */
1342static void fuse_vma_close(struct vm_area_struct *vma)
1343{
1344 filemap_write_and_wait(vma->vm_file->f_mapping);
1345}
1346
1347/*
1348 * Wait for writeback against this page to complete before allowing it
1349 * to be marked dirty again, and hence written back again, possibly
1350 * before the previous writepage completed.
1351 *
1352 * Block here, instead of in ->writepage(), so that the userspace fs
1353 * can only block processes actually operating on the filesystem.
1354 *
1355 * Otherwise unprivileged userspace fs would be able to block
1356 * unrelated:
1357 *
1358 * - page migration
1359 * - sync(2)
1360 * - try_to_free_pages() with order > PAGE_ALLOC_COSTLY_ORDER
1361 */
1362static int fuse_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
1363{
1364 struct page *page = vmf->page;
1365 /*
1366 * Don't use page->mapping as it may become NULL from a
1367 * concurrent truncate.
1368 */
1369 struct inode *inode = vma->vm_file->f_mapping->host;
1370
1371 fuse_wait_on_page_writeback(inode, page->index);
1372 return 0;
1373}
1374
1375static const struct vm_operations_struct fuse_file_vm_ops = {
1376 .close = fuse_vma_close,
1377 .fault = filemap_fault,
1378 .page_mkwrite = fuse_page_mkwrite,
1379};
1380
1381static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma)
1382{
1383 if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_MAYWRITE)) {
1384 struct inode *inode = file->f_dentry->d_inode;
1385 struct fuse_conn *fc = get_fuse_conn(inode);
1386 struct fuse_inode *fi = get_fuse_inode(inode);
1387 struct fuse_file *ff = file->private_data;
1388 /*
1389 * file may be written through mmap, so chain it onto the
1390 * inodes's write_file list
1391 */
1392 spin_lock(&fc->lock);
1393 if (list_empty(&ff->write_entry))
1394 list_add(&ff->write_entry, &fi->write_files);
1395 spin_unlock(&fc->lock);
1396 }
1397 file_accessed(file);
1398 vma->vm_ops = &fuse_file_vm_ops;
1399 return 0;
1400}
1401
1402static int fuse_direct_mmap(struct file *file, struct vm_area_struct *vma)
1403{
1404 /* Can't provide the coherency needed for MAP_SHARED */
1405 if (vma->vm_flags & VM_MAYSHARE)
1406 return -ENODEV;
1407
1408 invalidate_inode_pages2(file->f_mapping);
1409
1410 return generic_file_mmap(file, vma);
1411}
1412
1413static int convert_fuse_file_lock(const struct fuse_file_lock *ffl,
1414 struct file_lock *fl)
1415{
1416 switch (ffl->type) {
1417 case F_UNLCK:
1418 break;
1419
1420 case F_RDLCK:
1421 case F_WRLCK:
1422 if (ffl->start > OFFSET_MAX || ffl->end > OFFSET_MAX ||
1423 ffl->end < ffl->start)
1424 return -EIO;
1425
1426 fl->fl_start = ffl->start;
1427 fl->fl_end = ffl->end;
1428 fl->fl_pid = ffl->pid;
1429 break;
1430
1431 default:
1432 return -EIO;
1433 }
1434 fl->fl_type = ffl->type;
1435 return 0;
1436}
1437
1438static void fuse_lk_fill(struct fuse_req *req, struct file *file,
1439 const struct file_lock *fl, int opcode, pid_t pid,
1440 int flock)
1441{
1442 struct inode *inode = file->f_path.dentry->d_inode;
1443 struct fuse_conn *fc = get_fuse_conn(inode);
1444 struct fuse_file *ff = file->private_data;
1445 struct fuse_lk_in *arg = &req->misc.lk_in;
1446
1447 arg->fh = ff->fh;
1448 arg->owner = fuse_lock_owner_id(fc, fl->fl_owner);
1449 arg->lk.start = fl->fl_start;
1450 arg->lk.end = fl->fl_end;
1451 arg->lk.type = fl->fl_type;
1452 arg->lk.pid = pid;
1453 if (flock)
1454 arg->lk_flags |= FUSE_LK_FLOCK;
1455 req->in.h.opcode = opcode;
1456 req->in.h.nodeid = get_node_id(inode);
1457 req->in.numargs = 1;
1458 req->in.args[0].size = sizeof(*arg);
1459 req->in.args[0].value = arg;
1460}
1461
1462static int fuse_getlk(struct file *file, struct file_lock *fl)
1463{
1464 struct inode *inode = file->f_path.dentry->d_inode;
1465 struct fuse_conn *fc = get_fuse_conn(inode);
1466 struct fuse_req *req;
1467 struct fuse_lk_out outarg;
1468 int err;
1469
1470 req = fuse_get_req(fc);
1471 if (IS_ERR(req))
1472 return PTR_ERR(req);
1473
1474 fuse_lk_fill(req, file, fl, FUSE_GETLK, 0, 0);
1475 req->out.numargs = 1;
1476 req->out.args[0].size = sizeof(outarg);
1477 req->out.args[0].value = &outarg;
1478 fuse_request_send(fc, req);
1479 err = req->out.h.error;
1480 fuse_put_request(fc, req);
1481 if (!err)
1482 err = convert_fuse_file_lock(&outarg.lk, fl);
1483
1484 return err;
1485}
1486
1487static int fuse_setlk(struct file *file, struct file_lock *fl, int flock)
1488{
1489 struct inode *inode = file->f_path.dentry->d_inode;
1490 struct fuse_conn *fc = get_fuse_conn(inode);
1491 struct fuse_req *req;
1492 int opcode = (fl->fl_flags & FL_SLEEP) ? FUSE_SETLKW : FUSE_SETLK;
1493 pid_t pid = fl->fl_type != F_UNLCK ? current->tgid : 0;
1494 int err;
1495
1496 if (fl->fl_lmops && fl->fl_lmops->lm_grant) {
1497 /* NLM needs asynchronous locks, which we don't support yet */
1498 return -ENOLCK;
1499 }
1500
1501 /* Unlock on close is handled by the flush method */
1502 if (fl->fl_flags & FL_CLOSE)
1503 return 0;
1504
1505 req = fuse_get_req(fc);
1506 if (IS_ERR(req))
1507 return PTR_ERR(req);
1508
1509 fuse_lk_fill(req, file, fl, opcode, pid, flock);
1510 fuse_request_send(fc, req);
1511 err = req->out.h.error;
1512 /* locking is restartable */
1513 if (err == -EINTR)
1514 err = -ERESTARTSYS;
1515 fuse_put_request(fc, req);
1516 return err;
1517}
1518
1519static int fuse_file_lock(struct file *file, int cmd, struct file_lock *fl)
1520{
1521 struct inode *inode = file->f_path.dentry->d_inode;
1522 struct fuse_conn *fc = get_fuse_conn(inode);
1523 int err;
1524
1525 if (cmd == F_CANCELLK) {
1526 err = 0;
1527 } else if (cmd == F_GETLK) {
1528 if (fc->no_lock) {
1529 posix_test_lock(file, fl);
1530 err = 0;
1531 } else
1532 err = fuse_getlk(file, fl);
1533 } else {
1534 if (fc->no_lock)
1535 err = posix_lock_file(file, fl, NULL);
1536 else
1537 err = fuse_setlk(file, fl, 0);
1538 }
1539 return err;
1540}
1541
1542static int fuse_file_flock(struct file *file, int cmd, struct file_lock *fl)
1543{
1544 struct inode *inode = file->f_path.dentry->d_inode;
1545 struct fuse_conn *fc = get_fuse_conn(inode);
1546 int err;
1547
1548 if (fc->no_flock) {
1549 err = flock_lock_file_wait(file, fl);
1550 } else {
1551 struct fuse_file *ff = file->private_data;
1552
1553 /* emulate flock with POSIX locks */
1554 fl->fl_owner = (fl_owner_t) file;
1555 ff->flock = true;
1556 err = fuse_setlk(file, fl, 1);
1557 }
1558
1559 return err;
1560}
1561
1562static sector_t fuse_bmap(struct address_space *mapping, sector_t block)
1563{
1564 struct inode *inode = mapping->host;
1565 struct fuse_conn *fc = get_fuse_conn(inode);
1566 struct fuse_req *req;
1567 struct fuse_bmap_in inarg;
1568 struct fuse_bmap_out outarg;
1569 int err;
1570
1571 if (!inode->i_sb->s_bdev || fc->no_bmap)
1572 return 0;
1573
1574 req = fuse_get_req(fc);
1575 if (IS_ERR(req))
1576 return 0;
1577
1578 memset(&inarg, 0, sizeof(inarg));
1579 inarg.block = block;
1580 inarg.blocksize = inode->i_sb->s_blocksize;
1581 req->in.h.opcode = FUSE_BMAP;
1582 req->in.h.nodeid = get_node_id(inode);
1583 req->in.numargs = 1;
1584 req->in.args[0].size = sizeof(inarg);
1585 req->in.args[0].value = &inarg;
1586 req->out.numargs = 1;
1587 req->out.args[0].size = sizeof(outarg);
1588 req->out.args[0].value = &outarg;
1589 fuse_request_send(fc, req);
1590 err = req->out.h.error;
1591 fuse_put_request(fc, req);
1592 if (err == -ENOSYS)
1593 fc->no_bmap = 1;
1594
1595 return err ? 0 : outarg.block;
1596}
1597
1598static loff_t fuse_file_llseek(struct file *file, loff_t offset, int origin)
1599{
1600 loff_t retval;
1601 struct inode *inode = file->f_path.dentry->d_inode;
1602
1603 /* No i_mutex protection necessary for SEEK_CUR and SEEK_SET */
1604 if (origin == SEEK_CUR || origin == SEEK_SET)
1605 return generic_file_llseek(file, offset, origin);
1606
1607 mutex_lock(&inode->i_mutex);
1608 retval = fuse_update_attributes(inode, NULL, file, NULL);
1609 if (!retval)
1610 retval = generic_file_llseek(file, offset, origin);
1611 mutex_unlock(&inode->i_mutex);
1612
1613 return retval;
1614}
1615
1616static int fuse_ioctl_copy_user(struct page **pages, struct iovec *iov,
1617 unsigned int nr_segs, size_t bytes, bool to_user)
1618{
1619 struct iov_iter ii;
1620 int page_idx = 0;
1621
1622 if (!bytes)
1623 return 0;
1624
1625 iov_iter_init(&ii, iov, nr_segs, bytes, 0);
1626
1627 while (iov_iter_count(&ii)) {
1628 struct page *page = pages[page_idx++];
1629 size_t todo = min_t(size_t, PAGE_SIZE, iov_iter_count(&ii));
1630 void *kaddr;
1631
1632 kaddr = kmap(page);
1633
1634 while (todo) {
1635 char __user *uaddr = ii.iov->iov_base + ii.iov_offset;
1636 size_t iov_len = ii.iov->iov_len - ii.iov_offset;
1637 size_t copy = min(todo, iov_len);
1638 size_t left;
1639
1640 if (!to_user)
1641 left = copy_from_user(kaddr, uaddr, copy);
1642 else
1643 left = copy_to_user(uaddr, kaddr, copy);
1644
1645 if (unlikely(left))
1646 return -EFAULT;
1647
1648 iov_iter_advance(&ii, copy);
1649 todo -= copy;
1650 kaddr += copy;
1651 }
1652
1653 kunmap(page);
1654 }
1655
1656 return 0;
1657}
1658
1659/*
1660 * CUSE servers compiled on 32bit broke on 64bit kernels because the
1661 * ABI was defined to be 'struct iovec' which is different on 32bit
1662 * and 64bit. Fortunately we can determine which structure the server
1663 * used from the size of the reply.
1664 */
1665static int fuse_copy_ioctl_iovec_old(struct iovec *dst, void *src,
1666 size_t transferred, unsigned count,
1667 bool is_compat)
1668{
1669#ifdef CONFIG_COMPAT
1670 if (count * sizeof(struct compat_iovec) == transferred) {
1671 struct compat_iovec *ciov = src;
1672 unsigned i;
1673
1674 /*
1675 * With this interface a 32bit server cannot support
1676 * non-compat (i.e. ones coming from 64bit apps) ioctl
1677 * requests
1678 */
1679 if (!is_compat)
1680 return -EINVAL;
1681
1682 for (i = 0; i < count; i++) {
1683 dst[i].iov_base = compat_ptr(ciov[i].iov_base);
1684 dst[i].iov_len = ciov[i].iov_len;
1685 }
1686 return 0;
1687 }
1688#endif
1689
1690 if (count * sizeof(struct iovec) != transferred)
1691 return -EIO;
1692
1693 memcpy(dst, src, transferred);
1694 return 0;
1695}
1696
1697/* Make sure iov_length() won't overflow */
1698static int fuse_verify_ioctl_iov(struct iovec *iov, size_t count)
1699{
1700 size_t n;
1701 u32 max = FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT;
1702
1703 for (n = 0; n < count; n++, iov++) {
1704 if (iov->iov_len > (size_t) max)
1705 return -ENOMEM;
1706 max -= iov->iov_len;
1707 }
1708 return 0;
1709}
1710
1711static int fuse_copy_ioctl_iovec(struct fuse_conn *fc, struct iovec *dst,
1712 void *src, size_t transferred, unsigned count,
1713 bool is_compat)
1714{
1715 unsigned i;
1716 struct fuse_ioctl_iovec *fiov = src;
1717
1718 if (fc->minor < 16) {
1719 return fuse_copy_ioctl_iovec_old(dst, src, transferred,
1720 count, is_compat);
1721 }
1722
1723 if (count * sizeof(struct fuse_ioctl_iovec) != transferred)
1724 return -EIO;
1725
1726 for (i = 0; i < count; i++) {
1727 /* Did the server supply an inappropriate value? */
1728 if (fiov[i].base != (unsigned long) fiov[i].base ||
1729 fiov[i].len != (unsigned long) fiov[i].len)
1730 return -EIO;
1731
1732 dst[i].iov_base = (void __user *) (unsigned long) fiov[i].base;
1733 dst[i].iov_len = (size_t) fiov[i].len;
1734
1735#ifdef CONFIG_COMPAT
1736 if (is_compat &&
1737 (ptr_to_compat(dst[i].iov_base) != fiov[i].base ||
1738 (compat_size_t) dst[i].iov_len != fiov[i].len))
1739 return -EIO;
1740#endif
1741 }
1742
1743 return 0;
1744}
1745
1746
1747/*
1748 * For ioctls, there is no generic way to determine how much memory
1749 * needs to be read and/or written. Furthermore, ioctls are allowed
1750 * to dereference the passed pointer, so the parameter requires deep
1751 * copying but FUSE has no idea whatsoever about what to copy in or
1752 * out.
1753 *
1754 * This is solved by allowing FUSE server to retry ioctl with
1755 * necessary in/out iovecs. Let's assume the ioctl implementation
1756 * needs to read in the following structure.
1757 *
1758 * struct a {
1759 * char *buf;
1760 * size_t buflen;
1761 * }
1762 *
1763 * On the first callout to FUSE server, inarg->in_size and
1764 * inarg->out_size will be NULL; then, the server completes the ioctl
1765 * with FUSE_IOCTL_RETRY set in out->flags, out->in_iovs set to 1 and
1766 * the actual iov array to
1767 *
1768 * { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) } }
1769 *
1770 * which tells FUSE to copy in the requested area and retry the ioctl.
1771 * On the second round, the server has access to the structure and
1772 * from that it can tell what to look for next, so on the invocation,
1773 * it sets FUSE_IOCTL_RETRY, out->in_iovs to 2 and iov array to
1774 *
1775 * { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) },
1776 * { .iov_base = a.buf, .iov_len = a.buflen } }
1777 *
1778 * FUSE will copy both struct a and the pointed buffer from the
1779 * process doing the ioctl and retry ioctl with both struct a and the
1780 * buffer.
1781 *
1782 * This time, FUSE server has everything it needs and completes ioctl
1783 * without FUSE_IOCTL_RETRY which finishes the ioctl call.
1784 *
1785 * Copying data out works the same way.
1786 *
1787 * Note that if FUSE_IOCTL_UNRESTRICTED is clear, the kernel
1788 * automatically initializes in and out iovs by decoding @cmd with
1789 * _IOC_* macros and the server is not allowed to request RETRY. This
1790 * limits ioctl data transfers to well-formed ioctls and is the forced
1791 * behavior for all FUSE servers.
1792 */
1793long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
1794 unsigned int flags)
1795{
1796 struct fuse_file *ff = file->private_data;
1797 struct fuse_conn *fc = ff->fc;
1798 struct fuse_ioctl_in inarg = {
1799 .fh = ff->fh,
1800 .cmd = cmd,
1801 .arg = arg,
1802 .flags = flags
1803 };
1804 struct fuse_ioctl_out outarg;
1805 struct fuse_req *req = NULL;
1806 struct page **pages = NULL;
1807 struct iovec *iov_page = NULL;
1808 struct iovec *in_iov = NULL, *out_iov = NULL;
1809 unsigned int in_iovs = 0, out_iovs = 0, num_pages = 0, max_pages;
1810 size_t in_size, out_size, transferred;
1811 int err;
1812
1813#if BITS_PER_LONG == 32
1814 inarg.flags |= FUSE_IOCTL_32BIT;
1815#else
1816 if (flags & FUSE_IOCTL_COMPAT)
1817 inarg.flags |= FUSE_IOCTL_32BIT;
1818#endif
1819
1820 /* assume all the iovs returned by client always fits in a page */
1821 BUILD_BUG_ON(sizeof(struct fuse_ioctl_iovec) * FUSE_IOCTL_MAX_IOV > PAGE_SIZE);
1822
1823 err = -ENOMEM;
1824 pages = kcalloc(FUSE_MAX_PAGES_PER_REQ, sizeof(pages[0]), GFP_KERNEL);
1825 iov_page = (struct iovec *) __get_free_page(GFP_KERNEL);
1826 if (!pages || !iov_page)
1827 goto out;
1828
1829 /*
1830 * If restricted, initialize IO parameters as encoded in @cmd.
1831 * RETRY from server is not allowed.
1832 */
1833 if (!(flags & FUSE_IOCTL_UNRESTRICTED)) {
1834 struct iovec *iov = iov_page;
1835
1836 iov->iov_base = (void __user *)arg;
1837 iov->iov_len = _IOC_SIZE(cmd);
1838
1839 if (_IOC_DIR(cmd) & _IOC_WRITE) {
1840 in_iov = iov;
1841 in_iovs = 1;
1842 }
1843
1844 if (_IOC_DIR(cmd) & _IOC_READ) {
1845 out_iov = iov;
1846 out_iovs = 1;
1847 }
1848 }
1849
1850 retry:
1851 inarg.in_size = in_size = iov_length(in_iov, in_iovs);
1852 inarg.out_size = out_size = iov_length(out_iov, out_iovs);
1853
1854 /*
1855 * Out data can be used either for actual out data or iovs,
1856 * make sure there always is at least one page.
1857 */
1858 out_size = max_t(size_t, out_size, PAGE_SIZE);
1859 max_pages = DIV_ROUND_UP(max(in_size, out_size), PAGE_SIZE);
1860
1861 /* make sure there are enough buffer pages and init request with them */
1862 err = -ENOMEM;
1863 if (max_pages > FUSE_MAX_PAGES_PER_REQ)
1864 goto out;
1865 while (num_pages < max_pages) {
1866 pages[num_pages] = alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
1867 if (!pages[num_pages])
1868 goto out;
1869 num_pages++;
1870 }
1871
1872 req = fuse_get_req(fc);
1873 if (IS_ERR(req)) {
1874 err = PTR_ERR(req);
1875 req = NULL;
1876 goto out;
1877 }
1878 memcpy(req->pages, pages, sizeof(req->pages[0]) * num_pages);
1879 req->num_pages = num_pages;
1880
1881 /* okay, let's send it to the client */
1882 req->in.h.opcode = FUSE_IOCTL;
1883 req->in.h.nodeid = ff->nodeid;
1884 req->in.numargs = 1;
1885 req->in.args[0].size = sizeof(inarg);
1886 req->in.args[0].value = &inarg;
1887 if (in_size) {
1888 req->in.numargs++;
1889 req->in.args[1].size = in_size;
1890 req->in.argpages = 1;
1891
1892 err = fuse_ioctl_copy_user(pages, in_iov, in_iovs, in_size,
1893 false);
1894 if (err)
1895 goto out;
1896 }
1897
1898 req->out.numargs = 2;
1899 req->out.args[0].size = sizeof(outarg);
1900 req->out.args[0].value = &outarg;
1901 req->out.args[1].size = out_size;
1902 req->out.argpages = 1;
1903 req->out.argvar = 1;
1904
1905 fuse_request_send(fc, req);
1906 err = req->out.h.error;
1907 transferred = req->out.args[1].size;
1908 fuse_put_request(fc, req);
1909 req = NULL;
1910 if (err)
1911 goto out;
1912
1913 /* did it ask for retry? */
1914 if (outarg.flags & FUSE_IOCTL_RETRY) {
1915 void *vaddr;
1916
1917 /* no retry if in restricted mode */
1918 err = -EIO;
1919 if (!(flags & FUSE_IOCTL_UNRESTRICTED))
1920 goto out;
1921
1922 in_iovs = outarg.in_iovs;
1923 out_iovs = outarg.out_iovs;
1924
1925 /*
1926 * Make sure things are in boundary, separate checks
1927 * are to protect against overflow.
1928 */
1929 err = -ENOMEM;
1930 if (in_iovs > FUSE_IOCTL_MAX_IOV ||
1931 out_iovs > FUSE_IOCTL_MAX_IOV ||
1932 in_iovs + out_iovs > FUSE_IOCTL_MAX_IOV)
1933 goto out;
1934
1935 vaddr = kmap_atomic(pages[0]);
1936 err = fuse_copy_ioctl_iovec(fc, iov_page, vaddr,
1937 transferred, in_iovs + out_iovs,
1938 (flags & FUSE_IOCTL_COMPAT) != 0);
1939 kunmap_atomic(vaddr);
1940 if (err)
1941 goto out;
1942
1943 in_iov = iov_page;
1944 out_iov = in_iov + in_iovs;
1945
1946 err = fuse_verify_ioctl_iov(in_iov, in_iovs);
1947 if (err)
1948 goto out;
1949
1950 err = fuse_verify_ioctl_iov(out_iov, out_iovs);
1951 if (err)
1952 goto out;
1953
1954 goto retry;
1955 }
1956
1957 err = -EIO;
1958 if (transferred > inarg.out_size)
1959 goto out;
1960
1961 err = fuse_ioctl_copy_user(pages, out_iov, out_iovs, transferred, true);
1962 out:
1963 if (req)
1964 fuse_put_request(fc, req);
1965 free_page((unsigned long) iov_page);
1966 while (num_pages)
1967 __free_page(pages[--num_pages]);
1968 kfree(pages);
1969
1970 return err ? err : outarg.result;
1971}
1972EXPORT_SYMBOL_GPL(fuse_do_ioctl);
1973
1974long fuse_ioctl_common(struct file *file, unsigned int cmd,
1975 unsigned long arg, unsigned int flags)
1976{
1977 struct inode *inode = file->f_dentry->d_inode;
1978 struct fuse_conn *fc = get_fuse_conn(inode);
1979
1980 if (!fuse_allow_task(fc, current))
1981 return -EACCES;
1982
1983 if (is_bad_inode(inode))
1984 return -EIO;
1985
1986 return fuse_do_ioctl(file, cmd, arg, flags);
1987}
1988
1989static long fuse_file_ioctl(struct file *file, unsigned int cmd,
1990 unsigned long arg)
1991{
1992 return fuse_ioctl_common(file, cmd, arg, 0);
1993}
1994
1995static long fuse_file_compat_ioctl(struct file *file, unsigned int cmd,
1996 unsigned long arg)
1997{
1998 return fuse_ioctl_common(file, cmd, arg, FUSE_IOCTL_COMPAT);
1999}
2000
2001/*
2002 * All files which have been polled are linked to RB tree
2003 * fuse_conn->polled_files which is indexed by kh. Walk the tree and
2004 * find the matching one.
2005 */
2006static struct rb_node **fuse_find_polled_node(struct fuse_conn *fc, u64 kh,
2007 struct rb_node **parent_out)
2008{
2009 struct rb_node **link = &fc->polled_files.rb_node;
2010 struct rb_node *last = NULL;
2011
2012 while (*link) {
2013 struct fuse_file *ff;
2014
2015 last = *link;
2016 ff = rb_entry(last, struct fuse_file, polled_node);
2017
2018 if (kh < ff->kh)
2019 link = &last->rb_left;
2020 else if (kh > ff->kh)
2021 link = &last->rb_right;
2022 else
2023 return link;
2024 }
2025
2026 if (parent_out)
2027 *parent_out = last;
2028 return link;
2029}
2030
2031/*
2032 * The file is about to be polled. Make sure it's on the polled_files
2033 * RB tree. Note that files once added to the polled_files tree are
2034 * not removed before the file is released. This is because a file
2035 * polled once is likely to be polled again.
2036 */
2037static void fuse_register_polled_file(struct fuse_conn *fc,
2038 struct fuse_file *ff)
2039{
2040 spin_lock(&fc->lock);
2041 if (RB_EMPTY_NODE(&ff->polled_node)) {
2042 struct rb_node **link, *parent;
2043
2044 link = fuse_find_polled_node(fc, ff->kh, &parent);
2045 BUG_ON(*link);
2046 rb_link_node(&ff->polled_node, parent, link);
2047 rb_insert_color(&ff->polled_node, &fc->polled_files);
2048 }
2049 spin_unlock(&fc->lock);
2050}
2051
2052unsigned fuse_file_poll(struct file *file, poll_table *wait)
2053{
2054 struct fuse_file *ff = file->private_data;
2055 struct fuse_conn *fc = ff->fc;
2056 struct fuse_poll_in inarg = { .fh = ff->fh, .kh = ff->kh };
2057 struct fuse_poll_out outarg;
2058 struct fuse_req *req;
2059 int err;
2060
2061 if (fc->no_poll)
2062 return DEFAULT_POLLMASK;
2063
2064 poll_wait(file, &ff->poll_wait, wait);
2065
2066 /*
2067 * Ask for notification iff there's someone waiting for it.
2068 * The client may ignore the flag and always notify.
2069 */
2070 if (waitqueue_active(&ff->poll_wait)) {
2071 inarg.flags |= FUSE_POLL_SCHEDULE_NOTIFY;
2072 fuse_register_polled_file(fc, ff);
2073 }
2074
2075 req = fuse_get_req(fc);
2076 if (IS_ERR(req))
2077 return POLLERR;
2078
2079 req->in.h.opcode = FUSE_POLL;
2080 req->in.h.nodeid = ff->nodeid;
2081 req->in.numargs = 1;
2082 req->in.args[0].size = sizeof(inarg);
2083 req->in.args[0].value = &inarg;
2084 req->out.numargs = 1;
2085 req->out.args[0].size = sizeof(outarg);
2086 req->out.args[0].value = &outarg;
2087 fuse_request_send(fc, req);
2088 err = req->out.h.error;
2089 fuse_put_request(fc, req);
2090
2091 if (!err)
2092 return outarg.revents;
2093 if (err == -ENOSYS) {
2094 fc->no_poll = 1;
2095 return DEFAULT_POLLMASK;
2096 }
2097 return POLLERR;
2098}
2099EXPORT_SYMBOL_GPL(fuse_file_poll);
2100
2101/*
2102 * This is called from fuse_handle_notify() on FUSE_NOTIFY_POLL and
2103 * wakes up the poll waiters.
2104 */
2105int fuse_notify_poll_wakeup(struct fuse_conn *fc,
2106 struct fuse_notify_poll_wakeup_out *outarg)
2107{
2108 u64 kh = outarg->kh;
2109 struct rb_node **link;
2110
2111 spin_lock(&fc->lock);
2112
2113 link = fuse_find_polled_node(fc, kh, NULL);
2114 if (*link) {
2115 struct fuse_file *ff;
2116
2117 ff = rb_entry(*link, struct fuse_file, polled_node);
2118 wake_up_interruptible_sync(&ff->poll_wait);
2119 }
2120
2121 spin_unlock(&fc->lock);
2122 return 0;
2123}
2124
2125static ssize_t fuse_loop_dio(struct file *filp, const struct iovec *iov,
2126 unsigned long nr_segs, loff_t *ppos, int rw)
2127{
2128 const struct iovec *vector = iov;
2129 ssize_t ret = 0;
2130
2131 while (nr_segs > 0) {
2132 void __user *base;
2133 size_t len;
2134 ssize_t nr;
2135
2136 base = vector->iov_base;
2137 len = vector->iov_len;
2138 vector++;
2139 nr_segs--;
2140
2141 if (rw == WRITE)
2142 nr = __fuse_direct_write(filp, base, len, ppos);
2143 else
2144 nr = fuse_direct_read(filp, base, len, ppos);
2145
2146 if (nr < 0) {
2147 if (!ret)
2148 ret = nr;
2149 break;
2150 }
2151 ret += nr;
2152 if (nr != len)
2153 break;
2154 }
2155
2156 return ret;
2157}
2158
2159
2160static ssize_t
2161fuse_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
2162 loff_t offset, unsigned long nr_segs)
2163{
2164 ssize_t ret = 0;
2165 struct file *file = NULL;
2166 loff_t pos = 0;
2167
2168 file = iocb->ki_filp;
2169 pos = offset;
2170
2171 ret = fuse_loop_dio(file, iov, nr_segs, &pos, rw);
2172
2173 return ret;
2174}
2175
2176long fuse_file_fallocate(struct file *file, int mode, loff_t offset,
2177 loff_t length)
2178{
2179 struct fuse_file *ff = file->private_data;
2180 struct fuse_conn *fc = ff->fc;
2181 struct fuse_req *req;
2182 struct fuse_fallocate_in inarg = {
2183 .fh = ff->fh,
2184 .offset = offset,
2185 .length = length,
2186 .mode = mode
2187 };
2188 int err;
2189
2190 if (fc->no_fallocate)
2191 return -EOPNOTSUPP;
2192
2193 req = fuse_get_req(fc);
2194 if (IS_ERR(req))
2195 return PTR_ERR(req);
2196
2197 req->in.h.opcode = FUSE_FALLOCATE;
2198 req->in.h.nodeid = ff->nodeid;
2199 req->in.numargs = 1;
2200 req->in.args[0].size = sizeof(inarg);
2201 req->in.args[0].value = &inarg;
2202 fuse_request_send(fc, req);
2203 err = req->out.h.error;
2204 if (err == -ENOSYS) {
2205 fc->no_fallocate = 1;
2206 err = -EOPNOTSUPP;
2207 }
2208 fuse_put_request(fc, req);
2209
2210 return err;
2211}
2212EXPORT_SYMBOL_GPL(fuse_file_fallocate);
2213
2214static const struct file_operations fuse_file_operations = {
2215 .llseek = fuse_file_llseek,
2216 .read = do_sync_read,
2217 .aio_read = fuse_file_aio_read,
2218 .write = do_sync_write,
2219 .aio_write = fuse_file_aio_write,
2220 .mmap = fuse_file_mmap,
2221 .open = fuse_open,
2222 .flush = fuse_flush,
2223 .release = fuse_release,
2224 .fsync = fuse_fsync,
2225 .lock = fuse_file_lock,
2226 .flock = fuse_file_flock,
2227 .splice_read = generic_file_splice_read,
2228 .unlocked_ioctl = fuse_file_ioctl,
2229 .compat_ioctl = fuse_file_compat_ioctl,
2230 .poll = fuse_file_poll,
2231 .fallocate = fuse_file_fallocate,
2232};
2233
2234static const struct file_operations fuse_direct_io_file_operations = {
2235 .llseek = fuse_file_llseek,
2236 .read = fuse_direct_read,
2237 .write = fuse_direct_write,
2238 .mmap = fuse_direct_mmap,
2239 .open = fuse_open,
2240 .flush = fuse_flush,
2241 .release = fuse_release,
2242 .fsync = fuse_fsync,
2243 .lock = fuse_file_lock,
2244 .flock = fuse_file_flock,
2245 .unlocked_ioctl = fuse_file_ioctl,
2246 .compat_ioctl = fuse_file_compat_ioctl,
2247 .poll = fuse_file_poll,
2248 .fallocate = fuse_file_fallocate,
2249 /* no splice_read */
2250};
2251
2252static const struct address_space_operations fuse_file_aops = {
2253 .readpage = fuse_readpage,
2254 .writepage = fuse_writepage,
2255 .launder_page = fuse_launder_page,
2256 .readpages = fuse_readpages,
2257 .set_page_dirty = __set_page_dirty_nobuffers,
2258 .bmap = fuse_bmap,
2259 .direct_IO = fuse_direct_IO,
2260};
2261
2262void fuse_init_file_inode(struct inode *inode)
2263{
2264 inode->i_fop = &fuse_file_operations;
2265 inode->i_data.a_ops = &fuse_file_aops;
2266}