Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus
[linux-2.6] / fs / fuse / file.c
1 /*
2   FUSE: Filesystem in Userspace
3   Copyright (C) 2001-2006  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
16 static const struct file_operations fuse_direct_io_file_operations;
17
18 static int fuse_send_open(struct inode *inode, struct file *file, int isdir,
19                           struct fuse_open_out *outargp)
20 {
21         struct fuse_conn *fc = get_fuse_conn(inode);
22         struct fuse_open_in inarg;
23         struct fuse_req *req;
24         int err;
25
26         req = fuse_get_req(fc);
27         if (IS_ERR(req))
28                 return PTR_ERR(req);
29
30         memset(&inarg, 0, sizeof(inarg));
31         inarg.flags = file->f_flags & ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
32         req->in.h.opcode = isdir ? FUSE_OPENDIR : FUSE_OPEN;
33         req->in.h.nodeid = get_node_id(inode);
34         req->in.numargs = 1;
35         req->in.args[0].size = sizeof(inarg);
36         req->in.args[0].value = &inarg;
37         req->out.numargs = 1;
38         req->out.args[0].size = sizeof(*outargp);
39         req->out.args[0].value = outargp;
40         request_send(fc, req);
41         err = req->out.h.error;
42         fuse_put_request(fc, req);
43
44         return err;
45 }
46
47 struct fuse_file *fuse_file_alloc(void)
48 {
49         struct fuse_file *ff;
50         ff = kmalloc(sizeof(struct fuse_file), GFP_KERNEL);
51         if (ff) {
52                 ff->reserved_req = fuse_request_alloc();
53                 if (!ff->reserved_req) {
54                         kfree(ff);
55                         ff = NULL;
56                 }
57         }
58         return ff;
59 }
60
61 void fuse_file_free(struct fuse_file *ff)
62 {
63         fuse_request_free(ff->reserved_req);
64         kfree(ff);
65 }
66
67 void fuse_finish_open(struct inode *inode, struct file *file,
68                       struct fuse_file *ff, struct fuse_open_out *outarg)
69 {
70         if (outarg->open_flags & FOPEN_DIRECT_IO)
71                 file->f_op = &fuse_direct_io_file_operations;
72         if (!(outarg->open_flags & FOPEN_KEEP_CACHE))
73                 invalidate_mapping_pages(inode->i_mapping, 0, -1);
74         ff->fh = outarg->fh;
75         file->private_data = ff;
76 }
77
78 int fuse_open_common(struct inode *inode, struct file *file, int isdir)
79 {
80         struct fuse_open_out outarg;
81         struct fuse_file *ff;
82         int err;
83
84         /* VFS checks this, but only _after_ ->open() */
85         if (file->f_flags & O_DIRECT)
86                 return -EINVAL;
87
88         err = generic_file_open(inode, file);
89         if (err)
90                 return err;
91
92         /* If opening the root node, no lookup has been performed on
93            it, so the attributes must be refreshed */
94         if (get_node_id(inode) == FUSE_ROOT_ID) {
95                 err = fuse_do_getattr(inode);
96                 if (err)
97                         return err;
98         }
99
100         ff = fuse_file_alloc();
101         if (!ff)
102                 return -ENOMEM;
103
104         err = fuse_send_open(inode, file, isdir, &outarg);
105         if (err)
106                 fuse_file_free(ff);
107         else {
108                 if (isdir)
109                         outarg.open_flags &= ~FOPEN_DIRECT_IO;
110                 fuse_finish_open(inode, file, ff, &outarg);
111         }
112
113         return err;
114 }
115
116 struct fuse_req *fuse_release_fill(struct fuse_file *ff, u64 nodeid, int flags,
117                                    int opcode)
118 {
119         struct fuse_req *req = ff->reserved_req;
120         struct fuse_release_in *inarg = &req->misc.release_in;
121
122         inarg->fh = ff->fh;
123         inarg->flags = flags;
124         req->in.h.opcode = opcode;
125         req->in.h.nodeid = nodeid;
126         req->in.numargs = 1;
127         req->in.args[0].size = sizeof(struct fuse_release_in);
128         req->in.args[0].value = inarg;
129         kfree(ff);
130
131         return req;
132 }
133
134 int fuse_release_common(struct inode *inode, struct file *file, int isdir)
135 {
136         struct fuse_file *ff = file->private_data;
137         if (ff) {
138                 struct fuse_conn *fc = get_fuse_conn(inode);
139                 struct fuse_req *req;
140
141                 req = fuse_release_fill(ff, get_node_id(inode), file->f_flags,
142                                         isdir ? FUSE_RELEASEDIR : FUSE_RELEASE);
143
144                 /* Hold vfsmount and dentry until release is finished */
145                 req->vfsmount = mntget(file->f_path.mnt);
146                 req->dentry = dget(file->f_path.dentry);
147                 request_send_background(fc, req);
148         }
149
150         /* Return value is ignored by VFS */
151         return 0;
152 }
153
154 static int fuse_open(struct inode *inode, struct file *file)
155 {
156         return fuse_open_common(inode, file, 0);
157 }
158
159 static int fuse_release(struct inode *inode, struct file *file)
160 {
161         return fuse_release_common(inode, file, 0);
162 }
163
164 /*
165  * Scramble the ID space with XTEA, so that the value of the files_struct
166  * pointer is not exposed to userspace.
167  */
168 static u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id)
169 {
170         u32 *k = fc->scramble_key;
171         u64 v = (unsigned long) id;
172         u32 v0 = v;
173         u32 v1 = v >> 32;
174         u32 sum = 0;
175         int i;
176
177         for (i = 0; i < 32; i++) {
178                 v0 += ((v1 << 4 ^ v1 >> 5) + v1) ^ (sum + k[sum & 3]);
179                 sum += 0x9E3779B9;
180                 v1 += ((v0 << 4 ^ v0 >> 5) + v0) ^ (sum + k[sum>>11 & 3]);
181         }
182
183         return (u64) v0 + ((u64) v1 << 32);
184 }
185
186 static int fuse_flush(struct file *file, fl_owner_t id)
187 {
188         struct inode *inode = file->f_path.dentry->d_inode;
189         struct fuse_conn *fc = get_fuse_conn(inode);
190         struct fuse_file *ff = file->private_data;
191         struct fuse_req *req;
192         struct fuse_flush_in inarg;
193         int err;
194
195         if (is_bad_inode(inode))
196                 return -EIO;
197
198         if (fc->no_flush)
199                 return 0;
200
201         req = fuse_get_req_nofail(fc, file);
202         memset(&inarg, 0, sizeof(inarg));
203         inarg.fh = ff->fh;
204         inarg.lock_owner = fuse_lock_owner_id(fc, id);
205         req->in.h.opcode = FUSE_FLUSH;
206         req->in.h.nodeid = get_node_id(inode);
207         req->in.numargs = 1;
208         req->in.args[0].size = sizeof(inarg);
209         req->in.args[0].value = &inarg;
210         req->force = 1;
211         request_send(fc, req);
212         err = req->out.h.error;
213         fuse_put_request(fc, req);
214         if (err == -ENOSYS) {
215                 fc->no_flush = 1;
216                 err = 0;
217         }
218         return err;
219 }
220
221 int fuse_fsync_common(struct file *file, struct dentry *de, int datasync,
222                       int isdir)
223 {
224         struct inode *inode = de->d_inode;
225         struct fuse_conn *fc = get_fuse_conn(inode);
226         struct fuse_file *ff = file->private_data;
227         struct fuse_req *req;
228         struct fuse_fsync_in inarg;
229         int err;
230
231         if (is_bad_inode(inode))
232                 return -EIO;
233
234         if ((!isdir && fc->no_fsync) || (isdir && fc->no_fsyncdir))
235                 return 0;
236
237         req = fuse_get_req(fc);
238         if (IS_ERR(req))
239                 return PTR_ERR(req);
240
241         memset(&inarg, 0, sizeof(inarg));
242         inarg.fh = ff->fh;
243         inarg.fsync_flags = datasync ? 1 : 0;
244         req->in.h.opcode = isdir ? FUSE_FSYNCDIR : FUSE_FSYNC;
245         req->in.h.nodeid = get_node_id(inode);
246         req->in.numargs = 1;
247         req->in.args[0].size = sizeof(inarg);
248         req->in.args[0].value = &inarg;
249         request_send(fc, req);
250         err = req->out.h.error;
251         fuse_put_request(fc, req);
252         if (err == -ENOSYS) {
253                 if (isdir)
254                         fc->no_fsyncdir = 1;
255                 else
256                         fc->no_fsync = 1;
257                 err = 0;
258         }
259         return err;
260 }
261
262 static int fuse_fsync(struct file *file, struct dentry *de, int datasync)
263 {
264         return fuse_fsync_common(file, de, datasync, 0);
265 }
266
267 void fuse_read_fill(struct fuse_req *req, struct file *file,
268                     struct inode *inode, loff_t pos, size_t count, int opcode)
269 {
270         struct fuse_file *ff = file->private_data;
271         struct fuse_read_in *inarg = &req->misc.read_in;
272
273         inarg->fh = ff->fh;
274         inarg->offset = pos;
275         inarg->size = count;
276         req->in.h.opcode = opcode;
277         req->in.h.nodeid = get_node_id(inode);
278         req->in.numargs = 1;
279         req->in.args[0].size = sizeof(struct fuse_read_in);
280         req->in.args[0].value = inarg;
281         req->out.argpages = 1;
282         req->out.argvar = 1;
283         req->out.numargs = 1;
284         req->out.args[0].size = count;
285 }
286
287 static size_t fuse_send_read(struct fuse_req *req, struct file *file,
288                              struct inode *inode, loff_t pos, size_t count)
289 {
290         struct fuse_conn *fc = get_fuse_conn(inode);
291         fuse_read_fill(req, file, inode, pos, count, FUSE_READ);
292         request_send(fc, req);
293         return req->out.args[0].size;
294 }
295
296 static int fuse_readpage(struct file *file, struct page *page)
297 {
298         struct inode *inode = page->mapping->host;
299         struct fuse_conn *fc = get_fuse_conn(inode);
300         struct fuse_req *req;
301         int err;
302
303         err = -EIO;
304         if (is_bad_inode(inode))
305                 goto out;
306
307         req = fuse_get_req(fc);
308         err = PTR_ERR(req);
309         if (IS_ERR(req))
310                 goto out;
311
312         req->out.page_zeroing = 1;
313         req->num_pages = 1;
314         req->pages[0] = page;
315         fuse_send_read(req, file, inode, page_offset(page), PAGE_CACHE_SIZE);
316         err = req->out.h.error;
317         fuse_put_request(fc, req);
318         if (!err)
319                 SetPageUptodate(page);
320         fuse_invalidate_attr(inode); /* atime changed */
321  out:
322         unlock_page(page);
323         return err;
324 }
325
326 static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req)
327 {
328         int i;
329
330         fuse_invalidate_attr(req->pages[0]->mapping->host); /* atime changed */
331
332         for (i = 0; i < req->num_pages; i++) {
333                 struct page *page = req->pages[i];
334                 if (!req->out.h.error)
335                         SetPageUptodate(page);
336                 else
337                         SetPageError(page);
338                 unlock_page(page);
339         }
340         fuse_put_request(fc, req);
341 }
342
343 static void fuse_send_readpages(struct fuse_req *req, struct file *file,
344                                 struct inode *inode)
345 {
346         struct fuse_conn *fc = get_fuse_conn(inode);
347         loff_t pos = page_offset(req->pages[0]);
348         size_t count = req->num_pages << PAGE_CACHE_SHIFT;
349         req->out.page_zeroing = 1;
350         fuse_read_fill(req, file, inode, pos, count, FUSE_READ);
351         if (fc->async_read) {
352                 get_file(file);
353                 req->file = file;
354                 req->end = fuse_readpages_end;
355                 request_send_background(fc, req);
356         } else {
357                 request_send(fc, req);
358                 fuse_readpages_end(fc, req);
359         }
360 }
361
362 struct fuse_readpages_data {
363         struct fuse_req *req;
364         struct file *file;
365         struct inode *inode;
366 };
367
368 static int fuse_readpages_fill(void *_data, struct page *page)
369 {
370         struct fuse_readpages_data *data = _data;
371         struct fuse_req *req = data->req;
372         struct inode *inode = data->inode;
373         struct fuse_conn *fc = get_fuse_conn(inode);
374
375         if (req->num_pages &&
376             (req->num_pages == FUSE_MAX_PAGES_PER_REQ ||
377              (req->num_pages + 1) * PAGE_CACHE_SIZE > fc->max_read ||
378              req->pages[req->num_pages - 1]->index + 1 != page->index)) {
379                 fuse_send_readpages(req, data->file, inode);
380                 data->req = req = fuse_get_req(fc);
381                 if (IS_ERR(req)) {
382                         unlock_page(page);
383                         return PTR_ERR(req);
384                 }
385         }
386         req->pages[req->num_pages] = page;
387         req->num_pages ++;
388         return 0;
389 }
390
391 static int fuse_readpages(struct file *file, struct address_space *mapping,
392                           struct list_head *pages, unsigned nr_pages)
393 {
394         struct inode *inode = mapping->host;
395         struct fuse_conn *fc = get_fuse_conn(inode);
396         struct fuse_readpages_data data;
397         int err;
398
399         err = -EIO;
400         if (is_bad_inode(inode))
401                 goto out;
402
403         data.file = file;
404         data.inode = inode;
405         data.req = fuse_get_req(fc);
406         err = PTR_ERR(data.req);
407         if (IS_ERR(data.req))
408                 goto out;
409
410         err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data);
411         if (!err) {
412                 if (data.req->num_pages)
413                         fuse_send_readpages(data.req, file, inode);
414                 else
415                         fuse_put_request(fc, data.req);
416         }
417 out:
418         return err;
419 }
420
421 static size_t fuse_send_write(struct fuse_req *req, struct file *file,
422                               struct inode *inode, loff_t pos, size_t count)
423 {
424         struct fuse_conn *fc = get_fuse_conn(inode);
425         struct fuse_file *ff = file->private_data;
426         struct fuse_write_in inarg;
427         struct fuse_write_out outarg;
428
429         memset(&inarg, 0, sizeof(struct fuse_write_in));
430         inarg.fh = ff->fh;
431         inarg.offset = pos;
432         inarg.size = count;
433         req->in.h.opcode = FUSE_WRITE;
434         req->in.h.nodeid = get_node_id(inode);
435         req->in.argpages = 1;
436         req->in.numargs = 2;
437         req->in.args[0].size = sizeof(struct fuse_write_in);
438         req->in.args[0].value = &inarg;
439         req->in.args[1].size = count;
440         req->out.numargs = 1;
441         req->out.args[0].size = sizeof(struct fuse_write_out);
442         req->out.args[0].value = &outarg;
443         request_send(fc, req);
444         return outarg.size;
445 }
446
447 static int fuse_write_begin(struct file *file, struct address_space *mapping,
448                         loff_t pos, unsigned len, unsigned flags,
449                         struct page **pagep, void **fsdata)
450 {
451         pgoff_t index = pos >> PAGE_CACHE_SHIFT;
452
453         *pagep = __grab_cache_page(mapping, index);
454         if (!*pagep)
455                 return -ENOMEM;
456         return 0;
457 }
458
459 static int fuse_buffered_write(struct file *file, struct inode *inode,
460                                loff_t pos, unsigned count, struct page *page)
461 {
462         int err;
463         size_t nres;
464         struct fuse_conn *fc = get_fuse_conn(inode);
465         unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
466         struct fuse_req *req;
467
468         if (is_bad_inode(inode))
469                 return -EIO;
470
471         req = fuse_get_req(fc);
472         if (IS_ERR(req))
473                 return PTR_ERR(req);
474
475         req->num_pages = 1;
476         req->pages[0] = page;
477         req->page_offset = offset;
478         nres = fuse_send_write(req, file, inode, pos, count);
479         err = req->out.h.error;
480         fuse_put_request(fc, req);
481         if (!err && !nres)
482                 err = -EIO;
483         if (!err) {
484                 pos += nres;
485                 spin_lock(&fc->lock);
486                 if (pos > inode->i_size)
487                         i_size_write(inode, pos);
488                 spin_unlock(&fc->lock);
489
490                 if (count == PAGE_CACHE_SIZE)
491                         SetPageUptodate(page);
492         }
493         fuse_invalidate_attr(inode);
494         return err ? err : nres;
495 }
496
497 static int fuse_write_end(struct file *file, struct address_space *mapping,
498                         loff_t pos, unsigned len, unsigned copied,
499                         struct page *page, void *fsdata)
500 {
501         struct inode *inode = mapping->host;
502         int res = 0;
503
504         if (copied)
505                 res = fuse_buffered_write(file, inode, pos, copied, page);
506
507         unlock_page(page);
508         page_cache_release(page);
509         return res;
510 }
511
512 static void fuse_release_user_pages(struct fuse_req *req, int write)
513 {
514         unsigned i;
515
516         for (i = 0; i < req->num_pages; i++) {
517                 struct page *page = req->pages[i];
518                 if (write)
519                         set_page_dirty_lock(page);
520                 put_page(page);
521         }
522 }
523
524 static int fuse_get_user_pages(struct fuse_req *req, const char __user *buf,
525                                unsigned nbytes, int write)
526 {
527         unsigned long user_addr = (unsigned long) buf;
528         unsigned offset = user_addr & ~PAGE_MASK;
529         int npages;
530
531         /* This doesn't work with nfsd */
532         if (!current->mm)
533                 return -EPERM;
534
535         nbytes = min(nbytes, (unsigned) FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT);
536         npages = (nbytes + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
537         npages = min(max(npages, 1), FUSE_MAX_PAGES_PER_REQ);
538         down_read(&current->mm->mmap_sem);
539         npages = get_user_pages(current, current->mm, user_addr, npages, write,
540                                 0, req->pages, NULL);
541         up_read(&current->mm->mmap_sem);
542         if (npages < 0)
543                 return npages;
544
545         req->num_pages = npages;
546         req->page_offset = offset;
547         return 0;
548 }
549
550 static ssize_t fuse_direct_io(struct file *file, const char __user *buf,
551                               size_t count, loff_t *ppos, int write)
552 {
553         struct inode *inode = file->f_path.dentry->d_inode;
554         struct fuse_conn *fc = get_fuse_conn(inode);
555         size_t nmax = write ? fc->max_write : fc->max_read;
556         loff_t pos = *ppos;
557         ssize_t res = 0;
558         struct fuse_req *req;
559
560         if (is_bad_inode(inode))
561                 return -EIO;
562
563         req = fuse_get_req(fc);
564         if (IS_ERR(req))
565                 return PTR_ERR(req);
566
567         while (count) {
568                 size_t nres;
569                 size_t nbytes = min(count, nmax);
570                 int err = fuse_get_user_pages(req, buf, nbytes, !write);
571                 if (err) {
572                         res = err;
573                         break;
574                 }
575                 nbytes = (req->num_pages << PAGE_SHIFT) - req->page_offset;
576                 nbytes = min(count, nbytes);
577                 if (write)
578                         nres = fuse_send_write(req, file, inode, pos, nbytes);
579                 else
580                         nres = fuse_send_read(req, file, inode, pos, nbytes);
581                 fuse_release_user_pages(req, !write);
582                 if (req->out.h.error) {
583                         if (!res)
584                                 res = req->out.h.error;
585                         break;
586                 } else if (nres > nbytes) {
587                         res = -EIO;
588                         break;
589                 }
590                 count -= nres;
591                 res += nres;
592                 pos += nres;
593                 buf += nres;
594                 if (nres != nbytes)
595                         break;
596                 if (count) {
597                         fuse_put_request(fc, req);
598                         req = fuse_get_req(fc);
599                         if (IS_ERR(req))
600                                 break;
601                 }
602         }
603         fuse_put_request(fc, req);
604         if (res > 0) {
605                 if (write) {
606                         spin_lock(&fc->lock);
607                         if (pos > inode->i_size)
608                                 i_size_write(inode, pos);
609                         spin_unlock(&fc->lock);
610                 }
611                 *ppos = pos;
612         }
613         fuse_invalidate_attr(inode);
614
615         return res;
616 }
617
618 static ssize_t fuse_direct_read(struct file *file, char __user *buf,
619                                      size_t count, loff_t *ppos)
620 {
621         return fuse_direct_io(file, buf, count, ppos, 0);
622 }
623
624 static ssize_t fuse_direct_write(struct file *file, const char __user *buf,
625                                  size_t count, loff_t *ppos)
626 {
627         struct inode *inode = file->f_path.dentry->d_inode;
628         ssize_t res;
629         /* Don't allow parallel writes to the same file */
630         mutex_lock(&inode->i_mutex);
631         res = generic_write_checks(file, ppos, &count, 0);
632         if (!res)
633                 res = fuse_direct_io(file, buf, count, ppos, 1);
634         mutex_unlock(&inode->i_mutex);
635         return res;
636 }
637
638 static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma)
639 {
640         if ((vma->vm_flags & VM_SHARED)) {
641                 if ((vma->vm_flags & VM_WRITE))
642                         return -ENODEV;
643                 else
644                         vma->vm_flags &= ~VM_MAYWRITE;
645         }
646         return generic_file_mmap(file, vma);
647 }
648
649 static int fuse_set_page_dirty(struct page *page)
650 {
651         printk("fuse_set_page_dirty: should not happen\n");
652         dump_stack();
653         return 0;
654 }
655
656 static int convert_fuse_file_lock(const struct fuse_file_lock *ffl,
657                                   struct file_lock *fl)
658 {
659         switch (ffl->type) {
660         case F_UNLCK:
661                 break;
662
663         case F_RDLCK:
664         case F_WRLCK:
665                 if (ffl->start > OFFSET_MAX || ffl->end > OFFSET_MAX ||
666                     ffl->end < ffl->start)
667                         return -EIO;
668
669                 fl->fl_start = ffl->start;
670                 fl->fl_end = ffl->end;
671                 fl->fl_pid = ffl->pid;
672                 break;
673
674         default:
675                 return -EIO;
676         }
677         fl->fl_type = ffl->type;
678         return 0;
679 }
680
681 static void fuse_lk_fill(struct fuse_req *req, struct file *file,
682                          const struct file_lock *fl, int opcode, pid_t pid)
683 {
684         struct inode *inode = file->f_path.dentry->d_inode;
685         struct fuse_conn *fc = get_fuse_conn(inode);
686         struct fuse_file *ff = file->private_data;
687         struct fuse_lk_in *arg = &req->misc.lk_in;
688
689         arg->fh = ff->fh;
690         arg->owner = fuse_lock_owner_id(fc, fl->fl_owner);
691         arg->lk.start = fl->fl_start;
692         arg->lk.end = fl->fl_end;
693         arg->lk.type = fl->fl_type;
694         arg->lk.pid = pid;
695         req->in.h.opcode = opcode;
696         req->in.h.nodeid = get_node_id(inode);
697         req->in.numargs = 1;
698         req->in.args[0].size = sizeof(*arg);
699         req->in.args[0].value = arg;
700 }
701
702 static int fuse_getlk(struct file *file, struct file_lock *fl)
703 {
704         struct inode *inode = file->f_path.dentry->d_inode;
705         struct fuse_conn *fc = get_fuse_conn(inode);
706         struct fuse_req *req;
707         struct fuse_lk_out outarg;
708         int err;
709
710         req = fuse_get_req(fc);
711         if (IS_ERR(req))
712                 return PTR_ERR(req);
713
714         fuse_lk_fill(req, file, fl, FUSE_GETLK, 0);
715         req->out.numargs = 1;
716         req->out.args[0].size = sizeof(outarg);
717         req->out.args[0].value = &outarg;
718         request_send(fc, req);
719         err = req->out.h.error;
720         fuse_put_request(fc, req);
721         if (!err)
722                 err = convert_fuse_file_lock(&outarg.lk, fl);
723
724         return err;
725 }
726
727 static int fuse_setlk(struct file *file, struct file_lock *fl)
728 {
729         struct inode *inode = file->f_path.dentry->d_inode;
730         struct fuse_conn *fc = get_fuse_conn(inode);
731         struct fuse_req *req;
732         int opcode = (fl->fl_flags & FL_SLEEP) ? FUSE_SETLKW : FUSE_SETLK;
733         pid_t pid = fl->fl_type != F_UNLCK ? current->tgid : 0;
734         int err;
735
736         /* Unlock on close is handled by the flush method */
737         if (fl->fl_flags & FL_CLOSE)
738                 return 0;
739
740         req = fuse_get_req(fc);
741         if (IS_ERR(req))
742                 return PTR_ERR(req);
743
744         fuse_lk_fill(req, file, fl, opcode, pid);
745         request_send(fc, req);
746         err = req->out.h.error;
747         /* locking is restartable */
748         if (err == -EINTR)
749                 err = -ERESTARTSYS;
750         fuse_put_request(fc, req);
751         return err;
752 }
753
754 static int fuse_file_lock(struct file *file, int cmd, struct file_lock *fl)
755 {
756         struct inode *inode = file->f_path.dentry->d_inode;
757         struct fuse_conn *fc = get_fuse_conn(inode);
758         int err;
759
760         if (cmd == F_GETLK) {
761                 if (fc->no_lock) {
762                         posix_test_lock(file, fl);
763                         err = 0;
764                 } else
765                         err = fuse_getlk(file, fl);
766         } else {
767                 if (fc->no_lock)
768                         err = posix_lock_file_wait(file, fl);
769                 else
770                         err = fuse_setlk(file, fl);
771         }
772         return err;
773 }
774
775 static sector_t fuse_bmap(struct address_space *mapping, sector_t block)
776 {
777         struct inode *inode = mapping->host;
778         struct fuse_conn *fc = get_fuse_conn(inode);
779         struct fuse_req *req;
780         struct fuse_bmap_in inarg;
781         struct fuse_bmap_out outarg;
782         int err;
783
784         if (!inode->i_sb->s_bdev || fc->no_bmap)
785                 return 0;
786
787         req = fuse_get_req(fc);
788         if (IS_ERR(req))
789                 return 0;
790
791         memset(&inarg, 0, sizeof(inarg));
792         inarg.block = block;
793         inarg.blocksize = inode->i_sb->s_blocksize;
794         req->in.h.opcode = FUSE_BMAP;
795         req->in.h.nodeid = get_node_id(inode);
796         req->in.numargs = 1;
797         req->in.args[0].size = sizeof(inarg);
798         req->in.args[0].value = &inarg;
799         req->out.numargs = 1;
800         req->out.args[0].size = sizeof(outarg);
801         req->out.args[0].value = &outarg;
802         request_send(fc, req);
803         err = req->out.h.error;
804         fuse_put_request(fc, req);
805         if (err == -ENOSYS)
806                 fc->no_bmap = 1;
807
808         return err ? 0 : outarg.block;
809 }
810
811 static const struct file_operations fuse_file_operations = {
812         .llseek         = generic_file_llseek,
813         .read           = do_sync_read,
814         .aio_read       = generic_file_aio_read,
815         .write          = do_sync_write,
816         .aio_write      = generic_file_aio_write,
817         .mmap           = fuse_file_mmap,
818         .open           = fuse_open,
819         .flush          = fuse_flush,
820         .release        = fuse_release,
821         .fsync          = fuse_fsync,
822         .lock           = fuse_file_lock,
823         .splice_read    = generic_file_splice_read,
824 };
825
826 static const struct file_operations fuse_direct_io_file_operations = {
827         .llseek         = generic_file_llseek,
828         .read           = fuse_direct_read,
829         .write          = fuse_direct_write,
830         .open           = fuse_open,
831         .flush          = fuse_flush,
832         .release        = fuse_release,
833         .fsync          = fuse_fsync,
834         .lock           = fuse_file_lock,
835         /* no mmap and splice_read */
836 };
837
838 static const struct address_space_operations fuse_file_aops  = {
839         .readpage       = fuse_readpage,
840         .write_begin    = fuse_write_begin,
841         .write_end      = fuse_write_end,
842         .readpages      = fuse_readpages,
843         .set_page_dirty = fuse_set_page_dirty,
844         .bmap           = fuse_bmap,
845 };
846
847 void fuse_init_file_inode(struct inode *inode)
848 {
849         inode->i_fop = &fuse_file_operations;
850         inode->i_data.a_ops = &fuse_file_aops;
851 }