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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * This file contians vfs file ops for 9P2000.
4 *
5 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
6 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
7 */
8
9#include <linux/module.h>
10#include <linux/errno.h>
11#include <linux/fs.h>
12#include <linux/sched.h>
13#include <linux/file.h>
14#include <linux/stat.h>
15#include <linux/string.h>
16#include <linux/inet.h>
17#include <linux/list.h>
18#include <linux/pagemap.h>
19#include <linux/utsname.h>
20#include <linux/uaccess.h>
21#include <linux/uio.h>
22#include <linux/slab.h>
23#include <net/9p/9p.h>
24#include <net/9p/client.h>
25
26#include "v9fs.h"
27#include "v9fs_vfs.h"
28#include "fid.h"
29#include "cache.h"
30
31static const struct vm_operations_struct v9fs_file_vm_ops;
32static const struct vm_operations_struct v9fs_mmap_file_vm_ops;
33
34/**
35 * v9fs_file_open - open a file (or directory)
36 * @inode: inode to be opened
37 * @file: file being opened
38 *
39 */
40
41int v9fs_file_open(struct inode *inode, struct file *file)
42{
43 int err;
44 struct v9fs_inode *v9inode;
45 struct v9fs_session_info *v9ses;
46 struct p9_fid *fid, *writeback_fid;
47 int omode;
48
49 p9_debug(P9_DEBUG_VFS, "inode: %p file: %p\n", inode, file);
50 v9inode = V9FS_I(inode);
51 v9ses = v9fs_inode2v9ses(inode);
52 if (v9fs_proto_dotl(v9ses))
53 omode = v9fs_open_to_dotl_flags(file->f_flags);
54 else
55 omode = v9fs_uflags2omode(file->f_flags,
56 v9fs_proto_dotu(v9ses));
57 fid = file->private_data;
58 if (!fid) {
59 fid = v9fs_fid_clone(file_dentry(file));
60 if (IS_ERR(fid))
61 return PTR_ERR(fid);
62
63 err = p9_client_open(fid, omode);
64 if (err < 0) {
65 p9_fid_put(fid);
66 return err;
67 }
68 if ((file->f_flags & O_APPEND) &&
69 (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)))
70 generic_file_llseek(file, 0, SEEK_END);
71
72 file->private_data = fid;
73 }
74
75 mutex_lock(&v9inode->v_mutex);
76 if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
77 !v9inode->writeback_fid &&
78 ((file->f_flags & O_ACCMODE) != O_RDONLY)) {
79 /*
80 * clone a fid and add it to writeback_fid
81 * we do it during open time instead of
82 * page dirty time via write_begin/page_mkwrite
83 * because we want write after unlink usecase
84 * to work.
85 */
86 writeback_fid = v9fs_writeback_fid(file_dentry(file));
87 if (IS_ERR(writeback_fid)) {
88 err = PTR_ERR(writeback_fid);
89 mutex_unlock(&v9inode->v_mutex);
90 goto out_error;
91 }
92 v9inode->writeback_fid = (void *) writeback_fid;
93 }
94 mutex_unlock(&v9inode->v_mutex);
95 if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
96 fscache_use_cookie(v9fs_inode_cookie(v9inode),
97 file->f_mode & FMODE_WRITE);
98 v9fs_open_fid_add(inode, &fid);
99 return 0;
100out_error:
101 p9_fid_put(file->private_data);
102 file->private_data = NULL;
103 return err;
104}
105
106/**
107 * v9fs_file_lock - lock a file (or directory)
108 * @filp: file to be locked
109 * @cmd: lock command
110 * @fl: file lock structure
111 *
112 * Bugs: this looks like a local only lock, we should extend into 9P
113 * by using open exclusive
114 */
115
116static int v9fs_file_lock(struct file *filp, int cmd, struct file_lock *fl)
117{
118 struct inode *inode = file_inode(filp);
119
120 p9_debug(P9_DEBUG_VFS, "filp: %p lock: %p\n", filp, fl);
121
122 if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
123 filemap_write_and_wait(inode->i_mapping);
124 invalidate_mapping_pages(&inode->i_data, 0, -1);
125 }
126
127 return 0;
128}
129
130static int v9fs_file_do_lock(struct file *filp, int cmd, struct file_lock *fl)
131{
132 struct p9_flock flock;
133 struct p9_fid *fid;
134 uint8_t status = P9_LOCK_ERROR;
135 int res = 0;
136 unsigned char fl_type;
137 struct v9fs_session_info *v9ses;
138
139 fid = filp->private_data;
140 BUG_ON(fid == NULL);
141
142 BUG_ON((fl->fl_flags & FL_POSIX) != FL_POSIX);
143
144 res = locks_lock_file_wait(filp, fl);
145 if (res < 0)
146 goto out;
147
148 /* convert posix lock to p9 tlock args */
149 memset(&flock, 0, sizeof(flock));
150 /* map the lock type */
151 switch (fl->fl_type) {
152 case F_RDLCK:
153 flock.type = P9_LOCK_TYPE_RDLCK;
154 break;
155 case F_WRLCK:
156 flock.type = P9_LOCK_TYPE_WRLCK;
157 break;
158 case F_UNLCK:
159 flock.type = P9_LOCK_TYPE_UNLCK;
160 break;
161 }
162 flock.start = fl->fl_start;
163 if (fl->fl_end == OFFSET_MAX)
164 flock.length = 0;
165 else
166 flock.length = fl->fl_end - fl->fl_start + 1;
167 flock.proc_id = fl->fl_pid;
168 flock.client_id = fid->clnt->name;
169 if (IS_SETLKW(cmd))
170 flock.flags = P9_LOCK_FLAGS_BLOCK;
171
172 v9ses = v9fs_inode2v9ses(file_inode(filp));
173
174 /*
175 * if its a blocked request and we get P9_LOCK_BLOCKED as the status
176 * for lock request, keep on trying
177 */
178 for (;;) {
179 res = p9_client_lock_dotl(fid, &flock, &status);
180 if (res < 0)
181 goto out_unlock;
182
183 if (status != P9_LOCK_BLOCKED)
184 break;
185 if (status == P9_LOCK_BLOCKED && !IS_SETLKW(cmd))
186 break;
187 if (schedule_timeout_interruptible(v9ses->session_lock_timeout)
188 != 0)
189 break;
190 /*
191 * p9_client_lock_dotl overwrites flock.client_id with the
192 * server message, free and reuse the client name
193 */
194 if (flock.client_id != fid->clnt->name) {
195 kfree(flock.client_id);
196 flock.client_id = fid->clnt->name;
197 }
198 }
199
200 /* map 9p status to VFS status */
201 switch (status) {
202 case P9_LOCK_SUCCESS:
203 res = 0;
204 break;
205 case P9_LOCK_BLOCKED:
206 res = -EAGAIN;
207 break;
208 default:
209 WARN_ONCE(1, "unknown lock status code: %d\n", status);
210 fallthrough;
211 case P9_LOCK_ERROR:
212 case P9_LOCK_GRACE:
213 res = -ENOLCK;
214 break;
215 }
216
217out_unlock:
218 /*
219 * incase server returned error for lock request, revert
220 * it locally
221 */
222 if (res < 0 && fl->fl_type != F_UNLCK) {
223 fl_type = fl->fl_type;
224 fl->fl_type = F_UNLCK;
225 /* Even if this fails we want to return the remote error */
226 locks_lock_file_wait(filp, fl);
227 fl->fl_type = fl_type;
228 }
229 if (flock.client_id != fid->clnt->name)
230 kfree(flock.client_id);
231out:
232 return res;
233}
234
235static int v9fs_file_getlock(struct file *filp, struct file_lock *fl)
236{
237 struct p9_getlock glock;
238 struct p9_fid *fid;
239 int res = 0;
240
241 fid = filp->private_data;
242 BUG_ON(fid == NULL);
243
244 posix_test_lock(filp, fl);
245 /*
246 * if we have a conflicting lock locally, no need to validate
247 * with server
248 */
249 if (fl->fl_type != F_UNLCK)
250 return res;
251
252 /* convert posix lock to p9 tgetlock args */
253 memset(&glock, 0, sizeof(glock));
254 glock.type = P9_LOCK_TYPE_UNLCK;
255 glock.start = fl->fl_start;
256 if (fl->fl_end == OFFSET_MAX)
257 glock.length = 0;
258 else
259 glock.length = fl->fl_end - fl->fl_start + 1;
260 glock.proc_id = fl->fl_pid;
261 glock.client_id = fid->clnt->name;
262
263 res = p9_client_getlock_dotl(fid, &glock);
264 if (res < 0)
265 goto out;
266 /* map 9p lock type to os lock type */
267 switch (glock.type) {
268 case P9_LOCK_TYPE_RDLCK:
269 fl->fl_type = F_RDLCK;
270 break;
271 case P9_LOCK_TYPE_WRLCK:
272 fl->fl_type = F_WRLCK;
273 break;
274 case P9_LOCK_TYPE_UNLCK:
275 fl->fl_type = F_UNLCK;
276 break;
277 }
278 if (glock.type != P9_LOCK_TYPE_UNLCK) {
279 fl->fl_start = glock.start;
280 if (glock.length == 0)
281 fl->fl_end = OFFSET_MAX;
282 else
283 fl->fl_end = glock.start + glock.length - 1;
284 fl->fl_pid = -glock.proc_id;
285 }
286out:
287 if (glock.client_id != fid->clnt->name)
288 kfree(glock.client_id);
289 return res;
290}
291
292/**
293 * v9fs_file_lock_dotl - lock a file (or directory)
294 * @filp: file to be locked
295 * @cmd: lock command
296 * @fl: file lock structure
297 *
298 */
299
300static int v9fs_file_lock_dotl(struct file *filp, int cmd, struct file_lock *fl)
301{
302 struct inode *inode = file_inode(filp);
303 int ret = -ENOLCK;
304
305 p9_debug(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %pD\n",
306 filp, cmd, fl, filp);
307
308 if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
309 filemap_write_and_wait(inode->i_mapping);
310 invalidate_mapping_pages(&inode->i_data, 0, -1);
311 }
312
313 if (IS_SETLK(cmd) || IS_SETLKW(cmd))
314 ret = v9fs_file_do_lock(filp, cmd, fl);
315 else if (IS_GETLK(cmd))
316 ret = v9fs_file_getlock(filp, fl);
317 else
318 ret = -EINVAL;
319 return ret;
320}
321
322/**
323 * v9fs_file_flock_dotl - lock a file
324 * @filp: file to be locked
325 * @cmd: lock command
326 * @fl: file lock structure
327 *
328 */
329
330static int v9fs_file_flock_dotl(struct file *filp, int cmd,
331 struct file_lock *fl)
332{
333 struct inode *inode = file_inode(filp);
334 int ret = -ENOLCK;
335
336 p9_debug(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %pD\n",
337 filp, cmd, fl, filp);
338
339 if (!(fl->fl_flags & FL_FLOCK))
340 goto out_err;
341
342 if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
343 filemap_write_and_wait(inode->i_mapping);
344 invalidate_mapping_pages(&inode->i_data, 0, -1);
345 }
346 /* Convert flock to posix lock */
347 fl->fl_flags |= FL_POSIX;
348 fl->fl_flags ^= FL_FLOCK;
349
350 if (IS_SETLK(cmd) | IS_SETLKW(cmd))
351 ret = v9fs_file_do_lock(filp, cmd, fl);
352 else
353 ret = -EINVAL;
354out_err:
355 return ret;
356}
357
358/**
359 * v9fs_file_read_iter - read from a file
360 * @iocb: The operation parameters
361 * @to: The buffer to read into
362 *
363 */
364static ssize_t
365v9fs_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
366{
367 struct p9_fid *fid = iocb->ki_filp->private_data;
368 int ret, err = 0;
369
370 p9_debug(P9_DEBUG_VFS, "count %zu offset %lld\n",
371 iov_iter_count(to), iocb->ki_pos);
372
373 if (iocb->ki_filp->f_flags & O_NONBLOCK)
374 ret = p9_client_read_once(fid, iocb->ki_pos, to, &err);
375 else
376 ret = p9_client_read(fid, iocb->ki_pos, to, &err);
377 if (!ret)
378 return err;
379
380 iocb->ki_pos += ret;
381 return ret;
382}
383
384/**
385 * v9fs_file_write_iter - write to a file
386 * @iocb: The operation parameters
387 * @from: The data to write
388 *
389 */
390static ssize_t
391v9fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
392{
393 struct file *file = iocb->ki_filp;
394 ssize_t retval;
395 loff_t origin;
396 int err = 0;
397
398 retval = generic_write_checks(iocb, from);
399 if (retval <= 0)
400 return retval;
401
402 origin = iocb->ki_pos;
403 retval = p9_client_write(file->private_data, iocb->ki_pos, from, &err);
404 if (retval > 0) {
405 struct inode *inode = file_inode(file);
406 loff_t i_size;
407 unsigned long pg_start, pg_end;
408
409 pg_start = origin >> PAGE_SHIFT;
410 pg_end = (origin + retval - 1) >> PAGE_SHIFT;
411 if (inode->i_mapping && inode->i_mapping->nrpages)
412 invalidate_inode_pages2_range(inode->i_mapping,
413 pg_start, pg_end);
414 iocb->ki_pos += retval;
415 i_size = i_size_read(inode);
416 if (iocb->ki_pos > i_size) {
417 inode_add_bytes(inode, iocb->ki_pos - i_size);
418 /*
419 * Need to serialize against i_size_write() in
420 * v9fs_stat2inode()
421 */
422 v9fs_i_size_write(inode, iocb->ki_pos);
423 }
424 return retval;
425 }
426 return err;
427}
428
429static int v9fs_file_fsync(struct file *filp, loff_t start, loff_t end,
430 int datasync)
431{
432 struct p9_fid *fid;
433 struct inode *inode = filp->f_mapping->host;
434 struct p9_wstat wstat;
435 int retval;
436
437 retval = file_write_and_wait_range(filp, start, end);
438 if (retval)
439 return retval;
440
441 inode_lock(inode);
442 p9_debug(P9_DEBUG_VFS, "filp %p datasync %x\n", filp, datasync);
443
444 fid = filp->private_data;
445 v9fs_blank_wstat(&wstat);
446
447 retval = p9_client_wstat(fid, &wstat);
448 inode_unlock(inode);
449
450 return retval;
451}
452
453int v9fs_file_fsync_dotl(struct file *filp, loff_t start, loff_t end,
454 int datasync)
455{
456 struct p9_fid *fid;
457 struct inode *inode = filp->f_mapping->host;
458 int retval;
459
460 retval = file_write_and_wait_range(filp, start, end);
461 if (retval)
462 return retval;
463
464 inode_lock(inode);
465 p9_debug(P9_DEBUG_VFS, "filp %p datasync %x\n", filp, datasync);
466
467 fid = filp->private_data;
468
469 retval = p9_client_fsync(fid, datasync);
470 inode_unlock(inode);
471
472 return retval;
473}
474
475static int
476v9fs_file_mmap(struct file *filp, struct vm_area_struct *vma)
477{
478 int retval;
479
480
481 retval = generic_file_mmap(filp, vma);
482 if (!retval)
483 vma->vm_ops = &v9fs_file_vm_ops;
484
485 return retval;
486}
487
488static int
489v9fs_mmap_file_mmap(struct file *filp, struct vm_area_struct *vma)
490{
491 int retval;
492 struct inode *inode;
493 struct v9fs_inode *v9inode;
494 struct p9_fid *fid;
495
496 inode = file_inode(filp);
497 v9inode = V9FS_I(inode);
498 mutex_lock(&v9inode->v_mutex);
499 if (!v9inode->writeback_fid &&
500 (vma->vm_flags & VM_SHARED) &&
501 (vma->vm_flags & VM_WRITE)) {
502 /*
503 * clone a fid and add it to writeback_fid
504 * we do it during mmap instead of
505 * page dirty time via write_begin/page_mkwrite
506 * because we want write after unlink usecase
507 * to work.
508 */
509 fid = v9fs_writeback_fid(file_dentry(filp));
510 if (IS_ERR(fid)) {
511 retval = PTR_ERR(fid);
512 mutex_unlock(&v9inode->v_mutex);
513 return retval;
514 }
515 v9inode->writeback_fid = (void *) fid;
516 }
517 mutex_unlock(&v9inode->v_mutex);
518
519 retval = generic_file_mmap(filp, vma);
520 if (!retval)
521 vma->vm_ops = &v9fs_mmap_file_vm_ops;
522
523 return retval;
524}
525
526static vm_fault_t
527v9fs_vm_page_mkwrite(struct vm_fault *vmf)
528{
529 struct v9fs_inode *v9inode;
530 struct folio *folio = page_folio(vmf->page);
531 struct file *filp = vmf->vma->vm_file;
532 struct inode *inode = file_inode(filp);
533
534
535 p9_debug(P9_DEBUG_VFS, "folio %p fid %lx\n",
536 folio, (unsigned long)filp->private_data);
537
538 v9inode = V9FS_I(inode);
539
540 /* Wait for the page to be written to the cache before we allow it to
541 * be modified. We then assume the entire page will need writing back.
542 */
543#ifdef CONFIG_9P_FSCACHE
544 if (folio_test_fscache(folio) &&
545 folio_wait_fscache_killable(folio) < 0)
546 return VM_FAULT_NOPAGE;
547#endif
548
549 /* Update file times before taking page lock */
550 file_update_time(filp);
551
552 BUG_ON(!v9inode->writeback_fid);
553 if (folio_lock_killable(folio) < 0)
554 return VM_FAULT_RETRY;
555 if (folio_mapping(folio) != inode->i_mapping)
556 goto out_unlock;
557 folio_wait_stable(folio);
558
559 return VM_FAULT_LOCKED;
560out_unlock:
561 folio_unlock(folio);
562 return VM_FAULT_NOPAGE;
563}
564
565/**
566 * v9fs_mmap_file_read_iter - read from a file
567 * @iocb: The operation parameters
568 * @to: The buffer to read into
569 *
570 */
571static ssize_t
572v9fs_mmap_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
573{
574 /* TODO: Check if there are dirty pages */
575 return v9fs_file_read_iter(iocb, to);
576}
577
578/**
579 * v9fs_mmap_file_write_iter - write to a file
580 * @iocb: The operation parameters
581 * @from: The data to write
582 *
583 */
584static ssize_t
585v9fs_mmap_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
586{
587 /*
588 * TODO: invalidate mmaps on filp's inode between
589 * offset and offset+count
590 */
591 return v9fs_file_write_iter(iocb, from);
592}
593
594static void v9fs_mmap_vm_close(struct vm_area_struct *vma)
595{
596 struct inode *inode;
597
598 struct writeback_control wbc = {
599 .nr_to_write = LONG_MAX,
600 .sync_mode = WB_SYNC_ALL,
601 .range_start = (loff_t)vma->vm_pgoff * PAGE_SIZE,
602 /* absolute end, byte at end included */
603 .range_end = (loff_t)vma->vm_pgoff * PAGE_SIZE +
604 (vma->vm_end - vma->vm_start - 1),
605 };
606
607 if (!(vma->vm_flags & VM_SHARED))
608 return;
609
610 p9_debug(P9_DEBUG_VFS, "9p VMA close, %p, flushing", vma);
611
612 inode = file_inode(vma->vm_file);
613 filemap_fdatawrite_wbc(inode->i_mapping, &wbc);
614}
615
616
617static const struct vm_operations_struct v9fs_file_vm_ops = {
618 .fault = filemap_fault,
619 .map_pages = filemap_map_pages,
620 .page_mkwrite = v9fs_vm_page_mkwrite,
621};
622
623static const struct vm_operations_struct v9fs_mmap_file_vm_ops = {
624 .close = v9fs_mmap_vm_close,
625 .fault = filemap_fault,
626 .map_pages = filemap_map_pages,
627 .page_mkwrite = v9fs_vm_page_mkwrite,
628};
629
630
631const struct file_operations v9fs_cached_file_operations = {
632 .llseek = generic_file_llseek,
633 .read_iter = generic_file_read_iter,
634 .write_iter = generic_file_write_iter,
635 .open = v9fs_file_open,
636 .release = v9fs_dir_release,
637 .lock = v9fs_file_lock,
638 .mmap = v9fs_file_mmap,
639 .splice_read = generic_file_splice_read,
640 .splice_write = iter_file_splice_write,
641 .fsync = v9fs_file_fsync,
642};
643
644const struct file_operations v9fs_cached_file_operations_dotl = {
645 .llseek = generic_file_llseek,
646 .read_iter = generic_file_read_iter,
647 .write_iter = generic_file_write_iter,
648 .open = v9fs_file_open,
649 .release = v9fs_dir_release,
650 .lock = v9fs_file_lock_dotl,
651 .flock = v9fs_file_flock_dotl,
652 .mmap = v9fs_file_mmap,
653 .splice_read = generic_file_splice_read,
654 .splice_write = iter_file_splice_write,
655 .fsync = v9fs_file_fsync_dotl,
656};
657
658const struct file_operations v9fs_file_operations = {
659 .llseek = generic_file_llseek,
660 .read_iter = v9fs_file_read_iter,
661 .write_iter = v9fs_file_write_iter,
662 .open = v9fs_file_open,
663 .release = v9fs_dir_release,
664 .lock = v9fs_file_lock,
665 .mmap = generic_file_readonly_mmap,
666 .splice_read = generic_file_splice_read,
667 .splice_write = iter_file_splice_write,
668 .fsync = v9fs_file_fsync,
669};
670
671const struct file_operations v9fs_file_operations_dotl = {
672 .llseek = generic_file_llseek,
673 .read_iter = v9fs_file_read_iter,
674 .write_iter = v9fs_file_write_iter,
675 .open = v9fs_file_open,
676 .release = v9fs_dir_release,
677 .lock = v9fs_file_lock_dotl,
678 .flock = v9fs_file_flock_dotl,
679 .mmap = generic_file_readonly_mmap,
680 .splice_read = generic_file_splice_read,
681 .splice_write = iter_file_splice_write,
682 .fsync = v9fs_file_fsync_dotl,
683};
684
685const struct file_operations v9fs_mmap_file_operations = {
686 .llseek = generic_file_llseek,
687 .read_iter = v9fs_mmap_file_read_iter,
688 .write_iter = v9fs_mmap_file_write_iter,
689 .open = v9fs_file_open,
690 .release = v9fs_dir_release,
691 .lock = v9fs_file_lock,
692 .mmap = v9fs_mmap_file_mmap,
693 .splice_read = generic_file_splice_read,
694 .splice_write = iter_file_splice_write,
695 .fsync = v9fs_file_fsync,
696};
697
698const struct file_operations v9fs_mmap_file_operations_dotl = {
699 .llseek = generic_file_llseek,
700 .read_iter = v9fs_mmap_file_read_iter,
701 .write_iter = v9fs_mmap_file_write_iter,
702 .open = v9fs_file_open,
703 .release = v9fs_dir_release,
704 .lock = v9fs_file_lock_dotl,
705 .flock = v9fs_file_flock_dotl,
706 .mmap = v9fs_mmap_file_mmap,
707 .splice_read = generic_file_splice_read,
708 .splice_write = iter_file_splice_write,
709 .fsync = v9fs_file_fsync_dotl,
710};
1/*
2 * linux/fs/9p/vfs_file.c
3 *
4 * This file contians vfs file ops for 9P2000.
5 *
6 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
7 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2
11 * as published by the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to:
20 * Free Software Foundation
21 * 51 Franklin Street, Fifth Floor
22 * Boston, MA 02111-1301 USA
23 *
24 */
25
26#include <linux/module.h>
27#include <linux/errno.h>
28#include <linux/fs.h>
29#include <linux/sched.h>
30#include <linux/file.h>
31#include <linux/stat.h>
32#include <linux/string.h>
33#include <linux/inet.h>
34#include <linux/list.h>
35#include <linux/pagemap.h>
36#include <linux/utsname.h>
37#include <asm/uaccess.h>
38#include <linux/idr.h>
39#include <net/9p/9p.h>
40#include <net/9p/client.h>
41
42#include "v9fs.h"
43#include "v9fs_vfs.h"
44#include "fid.h"
45#include "cache.h"
46
47static const struct vm_operations_struct v9fs_file_vm_ops;
48
49/**
50 * v9fs_file_open - open a file (or directory)
51 * @inode: inode to be opened
52 * @file: file being opened
53 *
54 */
55
56int v9fs_file_open(struct inode *inode, struct file *file)
57{
58 int err;
59 struct v9fs_inode *v9inode;
60 struct v9fs_session_info *v9ses;
61 struct p9_fid *fid;
62 int omode;
63
64 P9_DPRINTK(P9_DEBUG_VFS, "inode: %p file: %p\n", inode, file);
65 v9inode = V9FS_I(inode);
66 v9ses = v9fs_inode2v9ses(inode);
67 if (v9fs_proto_dotl(v9ses))
68 omode = v9fs_open_to_dotl_flags(file->f_flags);
69 else
70 omode = v9fs_uflags2omode(file->f_flags,
71 v9fs_proto_dotu(v9ses));
72 fid = file->private_data;
73 if (!fid) {
74 fid = v9fs_fid_clone(file->f_path.dentry);
75 if (IS_ERR(fid))
76 return PTR_ERR(fid);
77
78 err = p9_client_open(fid, omode);
79 if (err < 0) {
80 p9_client_clunk(fid);
81 return err;
82 }
83 if (file->f_flags & O_TRUNC) {
84 i_size_write(inode, 0);
85 inode->i_blocks = 0;
86 }
87 if ((file->f_flags & O_APPEND) &&
88 (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)))
89 generic_file_llseek(file, 0, SEEK_END);
90 }
91
92 file->private_data = fid;
93 mutex_lock(&v9inode->v_mutex);
94 if (v9ses->cache && !v9inode->writeback_fid &&
95 ((file->f_flags & O_ACCMODE) != O_RDONLY)) {
96 /*
97 * clone a fid and add it to writeback_fid
98 * we do it during open time instead of
99 * page dirty time via write_begin/page_mkwrite
100 * because we want write after unlink usecase
101 * to work.
102 */
103 fid = v9fs_writeback_fid(file->f_path.dentry);
104 if (IS_ERR(fid)) {
105 err = PTR_ERR(fid);
106 mutex_unlock(&v9inode->v_mutex);
107 goto out_error;
108 }
109 v9inode->writeback_fid = (void *) fid;
110 }
111 mutex_unlock(&v9inode->v_mutex);
112#ifdef CONFIG_9P_FSCACHE
113 if (v9ses->cache)
114 v9fs_cache_inode_set_cookie(inode, file);
115#endif
116 return 0;
117out_error:
118 p9_client_clunk(file->private_data);
119 file->private_data = NULL;
120 return err;
121}
122
123/**
124 * v9fs_file_lock - lock a file (or directory)
125 * @filp: file to be locked
126 * @cmd: lock command
127 * @fl: file lock structure
128 *
129 * Bugs: this looks like a local only lock, we should extend into 9P
130 * by using open exclusive
131 */
132
133static int v9fs_file_lock(struct file *filp, int cmd, struct file_lock *fl)
134{
135 int res = 0;
136 struct inode *inode = filp->f_path.dentry->d_inode;
137
138 P9_DPRINTK(P9_DEBUG_VFS, "filp: %p lock: %p\n", filp, fl);
139
140 /* No mandatory locks */
141 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
142 return -ENOLCK;
143
144 if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
145 filemap_write_and_wait(inode->i_mapping);
146 invalidate_mapping_pages(&inode->i_data, 0, -1);
147 }
148
149 return res;
150}
151
152static int v9fs_file_do_lock(struct file *filp, int cmd, struct file_lock *fl)
153{
154 struct p9_flock flock;
155 struct p9_fid *fid;
156 uint8_t status;
157 int res = 0;
158 unsigned char fl_type;
159
160 fid = filp->private_data;
161 BUG_ON(fid == NULL);
162
163 if ((fl->fl_flags & FL_POSIX) != FL_POSIX)
164 BUG();
165
166 res = posix_lock_file_wait(filp, fl);
167 if (res < 0)
168 goto out;
169
170 /* convert posix lock to p9 tlock args */
171 memset(&flock, 0, sizeof(flock));
172 /* map the lock type */
173 switch (fl->fl_type) {
174 case F_RDLCK:
175 flock.type = P9_LOCK_TYPE_RDLCK;
176 break;
177 case F_WRLCK:
178 flock.type = P9_LOCK_TYPE_WRLCK;
179 break;
180 case F_UNLCK:
181 flock.type = P9_LOCK_TYPE_UNLCK;
182 break;
183 }
184 flock.start = fl->fl_start;
185 if (fl->fl_end == OFFSET_MAX)
186 flock.length = 0;
187 else
188 flock.length = fl->fl_end - fl->fl_start + 1;
189 flock.proc_id = fl->fl_pid;
190 flock.client_id = utsname()->nodename;
191 if (IS_SETLKW(cmd))
192 flock.flags = P9_LOCK_FLAGS_BLOCK;
193
194 /*
195 * if its a blocked request and we get P9_LOCK_BLOCKED as the status
196 * for lock request, keep on trying
197 */
198 for (;;) {
199 res = p9_client_lock_dotl(fid, &flock, &status);
200 if (res < 0)
201 break;
202
203 if (status != P9_LOCK_BLOCKED)
204 break;
205 if (status == P9_LOCK_BLOCKED && !IS_SETLKW(cmd))
206 break;
207 schedule_timeout_interruptible(P9_LOCK_TIMEOUT);
208 }
209
210 /* map 9p status to VFS status */
211 switch (status) {
212 case P9_LOCK_SUCCESS:
213 res = 0;
214 break;
215 case P9_LOCK_BLOCKED:
216 res = -EAGAIN;
217 break;
218 case P9_LOCK_ERROR:
219 case P9_LOCK_GRACE:
220 res = -ENOLCK;
221 break;
222 default:
223 BUG();
224 }
225
226 /*
227 * incase server returned error for lock request, revert
228 * it locally
229 */
230 if (res < 0 && fl->fl_type != F_UNLCK) {
231 fl_type = fl->fl_type;
232 fl->fl_type = F_UNLCK;
233 res = posix_lock_file_wait(filp, fl);
234 fl->fl_type = fl_type;
235 }
236out:
237 return res;
238}
239
240static int v9fs_file_getlock(struct file *filp, struct file_lock *fl)
241{
242 struct p9_getlock glock;
243 struct p9_fid *fid;
244 int res = 0;
245
246 fid = filp->private_data;
247 BUG_ON(fid == NULL);
248
249 posix_test_lock(filp, fl);
250 /*
251 * if we have a conflicting lock locally, no need to validate
252 * with server
253 */
254 if (fl->fl_type != F_UNLCK)
255 return res;
256
257 /* convert posix lock to p9 tgetlock args */
258 memset(&glock, 0, sizeof(glock));
259 glock.type = P9_LOCK_TYPE_UNLCK;
260 glock.start = fl->fl_start;
261 if (fl->fl_end == OFFSET_MAX)
262 glock.length = 0;
263 else
264 glock.length = fl->fl_end - fl->fl_start + 1;
265 glock.proc_id = fl->fl_pid;
266 glock.client_id = utsname()->nodename;
267
268 res = p9_client_getlock_dotl(fid, &glock);
269 if (res < 0)
270 return res;
271 /* map 9p lock type to os lock type */
272 switch (glock.type) {
273 case P9_LOCK_TYPE_RDLCK:
274 fl->fl_type = F_RDLCK;
275 break;
276 case P9_LOCK_TYPE_WRLCK:
277 fl->fl_type = F_WRLCK;
278 break;
279 case P9_LOCK_TYPE_UNLCK:
280 fl->fl_type = F_UNLCK;
281 break;
282 }
283 if (glock.type != P9_LOCK_TYPE_UNLCK) {
284 fl->fl_start = glock.start;
285 if (glock.length == 0)
286 fl->fl_end = OFFSET_MAX;
287 else
288 fl->fl_end = glock.start + glock.length - 1;
289 fl->fl_pid = glock.proc_id;
290 }
291 return res;
292}
293
294/**
295 * v9fs_file_lock_dotl - lock a file (or directory)
296 * @filp: file to be locked
297 * @cmd: lock command
298 * @fl: file lock structure
299 *
300 */
301
302static int v9fs_file_lock_dotl(struct file *filp, int cmd, struct file_lock *fl)
303{
304 struct inode *inode = filp->f_path.dentry->d_inode;
305 int ret = -ENOLCK;
306
307 P9_DPRINTK(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %s\n", filp,
308 cmd, fl, filp->f_path.dentry->d_name.name);
309
310 /* No mandatory locks */
311 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
312 goto out_err;
313
314 if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
315 filemap_write_and_wait(inode->i_mapping);
316 invalidate_mapping_pages(&inode->i_data, 0, -1);
317 }
318
319 if (IS_SETLK(cmd) || IS_SETLKW(cmd))
320 ret = v9fs_file_do_lock(filp, cmd, fl);
321 else if (IS_GETLK(cmd))
322 ret = v9fs_file_getlock(filp, fl);
323 else
324 ret = -EINVAL;
325out_err:
326 return ret;
327}
328
329/**
330 * v9fs_file_flock_dotl - lock a file
331 * @filp: file to be locked
332 * @cmd: lock command
333 * @fl: file lock structure
334 *
335 */
336
337static int v9fs_file_flock_dotl(struct file *filp, int cmd,
338 struct file_lock *fl)
339{
340 struct inode *inode = filp->f_path.dentry->d_inode;
341 int ret = -ENOLCK;
342
343 P9_DPRINTK(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %s\n", filp,
344 cmd, fl, filp->f_path.dentry->d_name.name);
345
346 /* No mandatory locks */
347 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
348 goto out_err;
349
350 if (!(fl->fl_flags & FL_FLOCK))
351 goto out_err;
352
353 if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
354 filemap_write_and_wait(inode->i_mapping);
355 invalidate_mapping_pages(&inode->i_data, 0, -1);
356 }
357 /* Convert flock to posix lock */
358 fl->fl_owner = (fl_owner_t)filp;
359 fl->fl_start = 0;
360 fl->fl_end = OFFSET_MAX;
361 fl->fl_flags |= FL_POSIX;
362 fl->fl_flags ^= FL_FLOCK;
363
364 if (IS_SETLK(cmd) | IS_SETLKW(cmd))
365 ret = v9fs_file_do_lock(filp, cmd, fl);
366 else
367 ret = -EINVAL;
368out_err:
369 return ret;
370}
371
372/**
373 * v9fs_fid_readn - read from a fid
374 * @fid: fid to read
375 * @data: data buffer to read data into
376 * @udata: user data buffer to read data into
377 * @count: size of buffer
378 * @offset: offset at which to read data
379 *
380 */
381ssize_t
382v9fs_fid_readn(struct p9_fid *fid, char *data, char __user *udata, u32 count,
383 u64 offset)
384{
385 int n, total, size;
386
387 P9_DPRINTK(P9_DEBUG_VFS, "fid %d offset %llu count %d\n", fid->fid,
388 (long long unsigned) offset, count);
389 n = 0;
390 total = 0;
391 size = fid->iounit ? fid->iounit : fid->clnt->msize - P9_IOHDRSZ;
392 do {
393 n = p9_client_read(fid, data, udata, offset, count);
394 if (n <= 0)
395 break;
396
397 if (data)
398 data += n;
399 if (udata)
400 udata += n;
401
402 offset += n;
403 count -= n;
404 total += n;
405 } while (count > 0 && n == size);
406
407 if (n < 0)
408 total = n;
409
410 return total;
411}
412
413/**
414 * v9fs_file_readn - read from a file
415 * @filp: file pointer to read
416 * @data: data buffer to read data into
417 * @udata: user data buffer to read data into
418 * @count: size of buffer
419 * @offset: offset at which to read data
420 *
421 */
422ssize_t
423v9fs_file_readn(struct file *filp, char *data, char __user *udata, u32 count,
424 u64 offset)
425{
426 return v9fs_fid_readn(filp->private_data, data, udata, count, offset);
427}
428
429/**
430 * v9fs_file_read - read from a file
431 * @filp: file pointer to read
432 * @udata: user data buffer to read data into
433 * @count: size of buffer
434 * @offset: offset at which to read data
435 *
436 */
437
438static ssize_t
439v9fs_file_read(struct file *filp, char __user *udata, size_t count,
440 loff_t * offset)
441{
442 int ret;
443 struct p9_fid *fid;
444 size_t size;
445
446 P9_DPRINTK(P9_DEBUG_VFS, "count %zu offset %lld\n", count, *offset);
447 fid = filp->private_data;
448
449 size = fid->iounit ? fid->iounit : fid->clnt->msize - P9_IOHDRSZ;
450 if (count > size)
451 ret = v9fs_file_readn(filp, NULL, udata, count, *offset);
452 else
453 ret = p9_client_read(fid, NULL, udata, *offset, count);
454
455 if (ret > 0)
456 *offset += ret;
457
458 return ret;
459}
460
461ssize_t
462v9fs_file_write_internal(struct inode *inode, struct p9_fid *fid,
463 const char __user *data, size_t count,
464 loff_t *offset, int invalidate)
465{
466 int n;
467 loff_t i_size;
468 size_t total = 0;
469 struct p9_client *clnt;
470 loff_t origin = *offset;
471 unsigned long pg_start, pg_end;
472
473 P9_DPRINTK(P9_DEBUG_VFS, "data %p count %d offset %x\n", data,
474 (int)count, (int)*offset);
475
476 clnt = fid->clnt;
477 do {
478 n = p9_client_write(fid, NULL, data+total, origin+total, count);
479 if (n <= 0)
480 break;
481 count -= n;
482 total += n;
483 } while (count > 0);
484
485 if (invalidate && (total > 0)) {
486 pg_start = origin >> PAGE_CACHE_SHIFT;
487 pg_end = (origin + total - 1) >> PAGE_CACHE_SHIFT;
488 if (inode->i_mapping && inode->i_mapping->nrpages)
489 invalidate_inode_pages2_range(inode->i_mapping,
490 pg_start, pg_end);
491 *offset += total;
492 i_size = i_size_read(inode);
493 if (*offset > i_size) {
494 inode_add_bytes(inode, *offset - i_size);
495 i_size_write(inode, *offset);
496 }
497 }
498 if (n < 0)
499 return n;
500
501 return total;
502}
503
504/**
505 * v9fs_file_write - write to a file
506 * @filp: file pointer to write
507 * @data: data buffer to write data from
508 * @count: size of buffer
509 * @offset: offset at which to write data
510 *
511 */
512static ssize_t
513v9fs_file_write(struct file *filp, const char __user * data,
514 size_t count, loff_t *offset)
515{
516 ssize_t retval = 0;
517 loff_t origin = *offset;
518
519
520 retval = generic_write_checks(filp, &origin, &count, 0);
521 if (retval)
522 goto out;
523
524 retval = -EINVAL;
525 if ((ssize_t) count < 0)
526 goto out;
527 retval = 0;
528 if (!count)
529 goto out;
530
531 retval = v9fs_file_write_internal(filp->f_path.dentry->d_inode,
532 filp->private_data,
533 data, count, &origin, 1);
534 /* update offset on successful write */
535 if (retval > 0)
536 *offset = origin;
537out:
538 return retval;
539}
540
541
542static int v9fs_file_fsync(struct file *filp, loff_t start, loff_t end,
543 int datasync)
544{
545 struct p9_fid *fid;
546 struct inode *inode = filp->f_mapping->host;
547 struct p9_wstat wstat;
548 int retval;
549
550 retval = filemap_write_and_wait_range(inode->i_mapping, start, end);
551 if (retval)
552 return retval;
553
554 mutex_lock(&inode->i_mutex);
555 P9_DPRINTK(P9_DEBUG_VFS, "filp %p datasync %x\n", filp, datasync);
556
557 fid = filp->private_data;
558 v9fs_blank_wstat(&wstat);
559
560 retval = p9_client_wstat(fid, &wstat);
561 mutex_unlock(&inode->i_mutex);
562
563 return retval;
564}
565
566int v9fs_file_fsync_dotl(struct file *filp, loff_t start, loff_t end,
567 int datasync)
568{
569 struct p9_fid *fid;
570 struct inode *inode = filp->f_mapping->host;
571 int retval;
572
573 retval = filemap_write_and_wait_range(inode->i_mapping, start, end);
574 if (retval)
575 return retval;
576
577 mutex_lock(&inode->i_mutex);
578 P9_DPRINTK(P9_DEBUG_VFS, "v9fs_file_fsync_dotl: filp %p datasync %x\n",
579 filp, datasync);
580
581 fid = filp->private_data;
582
583 retval = p9_client_fsync(fid, datasync);
584 mutex_unlock(&inode->i_mutex);
585
586 return retval;
587}
588
589static int
590v9fs_file_mmap(struct file *file, struct vm_area_struct *vma)
591{
592 int retval;
593
594 retval = generic_file_mmap(file, vma);
595 if (!retval)
596 vma->vm_ops = &v9fs_file_vm_ops;
597
598 return retval;
599}
600
601static int
602v9fs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
603{
604 struct v9fs_inode *v9inode;
605 struct page *page = vmf->page;
606 struct file *filp = vma->vm_file;
607 struct inode *inode = filp->f_path.dentry->d_inode;
608
609
610 P9_DPRINTK(P9_DEBUG_VFS, "page %p fid %lx\n",
611 page, (unsigned long)filp->private_data);
612
613 v9inode = V9FS_I(inode);
614 /* make sure the cache has finished storing the page */
615 v9fs_fscache_wait_on_page_write(inode, page);
616 BUG_ON(!v9inode->writeback_fid);
617 lock_page(page);
618 if (page->mapping != inode->i_mapping)
619 goto out_unlock;
620
621 return VM_FAULT_LOCKED;
622out_unlock:
623 unlock_page(page);
624 return VM_FAULT_NOPAGE;
625}
626
627static ssize_t
628v9fs_direct_read(struct file *filp, char __user *udata, size_t count,
629 loff_t *offsetp)
630{
631 loff_t size, offset;
632 struct inode *inode;
633 struct address_space *mapping;
634
635 offset = *offsetp;
636 mapping = filp->f_mapping;
637 inode = mapping->host;
638 if (!count)
639 return 0;
640 size = i_size_read(inode);
641 if (offset < size)
642 filemap_write_and_wait_range(mapping, offset,
643 offset + count - 1);
644
645 return v9fs_file_read(filp, udata, count, offsetp);
646}
647
648/**
649 * v9fs_cached_file_read - read from a file
650 * @filp: file pointer to read
651 * @udata: user data buffer to read data into
652 * @count: size of buffer
653 * @offset: offset at which to read data
654 *
655 */
656static ssize_t
657v9fs_cached_file_read(struct file *filp, char __user *data, size_t count,
658 loff_t *offset)
659{
660 if (filp->f_flags & O_DIRECT)
661 return v9fs_direct_read(filp, data, count, offset);
662 return do_sync_read(filp, data, count, offset);
663}
664
665static ssize_t
666v9fs_direct_write(struct file *filp, const char __user * data,
667 size_t count, loff_t *offsetp)
668{
669 loff_t offset;
670 ssize_t retval;
671 struct inode *inode;
672 struct address_space *mapping;
673
674 offset = *offsetp;
675 mapping = filp->f_mapping;
676 inode = mapping->host;
677 if (!count)
678 return 0;
679
680 mutex_lock(&inode->i_mutex);
681 retval = filemap_write_and_wait_range(mapping, offset,
682 offset + count - 1);
683 if (retval)
684 goto err_out;
685 /*
686 * After a write we want buffered reads to be sure to go to disk to get
687 * the new data. We invalidate clean cached page from the region we're
688 * about to write. We do this *before* the write so that if we fail
689 * here we fall back to buffered write
690 */
691 if (mapping->nrpages) {
692 pgoff_t pg_start = offset >> PAGE_CACHE_SHIFT;
693 pgoff_t pg_end = (offset + count - 1) >> PAGE_CACHE_SHIFT;
694
695 retval = invalidate_inode_pages2_range(mapping,
696 pg_start, pg_end);
697 /*
698 * If a page can not be invalidated, fall back
699 * to buffered write.
700 */
701 if (retval) {
702 if (retval == -EBUSY)
703 goto buff_write;
704 goto err_out;
705 }
706 }
707 retval = v9fs_file_write(filp, data, count, offsetp);
708err_out:
709 mutex_unlock(&inode->i_mutex);
710 return retval;
711
712buff_write:
713 mutex_unlock(&inode->i_mutex);
714 return do_sync_write(filp, data, count, offsetp);
715}
716
717/**
718 * v9fs_cached_file_write - write to a file
719 * @filp: file pointer to write
720 * @data: data buffer to write data from
721 * @count: size of buffer
722 * @offset: offset at which to write data
723 *
724 */
725static ssize_t
726v9fs_cached_file_write(struct file *filp, const char __user * data,
727 size_t count, loff_t *offset)
728{
729
730 if (filp->f_flags & O_DIRECT)
731 return v9fs_direct_write(filp, data, count, offset);
732 return do_sync_write(filp, data, count, offset);
733}
734
735static const struct vm_operations_struct v9fs_file_vm_ops = {
736 .fault = filemap_fault,
737 .page_mkwrite = v9fs_vm_page_mkwrite,
738};
739
740
741const struct file_operations v9fs_cached_file_operations = {
742 .llseek = generic_file_llseek,
743 .read = v9fs_cached_file_read,
744 .write = v9fs_cached_file_write,
745 .aio_read = generic_file_aio_read,
746 .aio_write = generic_file_aio_write,
747 .open = v9fs_file_open,
748 .release = v9fs_dir_release,
749 .lock = v9fs_file_lock,
750 .mmap = v9fs_file_mmap,
751 .fsync = v9fs_file_fsync,
752};
753
754const struct file_operations v9fs_cached_file_operations_dotl = {
755 .llseek = generic_file_llseek,
756 .read = v9fs_cached_file_read,
757 .write = v9fs_cached_file_write,
758 .aio_read = generic_file_aio_read,
759 .aio_write = generic_file_aio_write,
760 .open = v9fs_file_open,
761 .release = v9fs_dir_release,
762 .lock = v9fs_file_lock_dotl,
763 .flock = v9fs_file_flock_dotl,
764 .mmap = v9fs_file_mmap,
765 .fsync = v9fs_file_fsync_dotl,
766};
767
768const struct file_operations v9fs_file_operations = {
769 .llseek = generic_file_llseek,
770 .read = v9fs_file_read,
771 .write = v9fs_file_write,
772 .open = v9fs_file_open,
773 .release = v9fs_dir_release,
774 .lock = v9fs_file_lock,
775 .mmap = generic_file_readonly_mmap,
776 .fsync = v9fs_file_fsync,
777};
778
779const struct file_operations v9fs_file_operations_dotl = {
780 .llseek = generic_file_llseek,
781 .read = v9fs_file_read,
782 .write = v9fs_file_write,
783 .open = v9fs_file_open,
784 .release = v9fs_dir_release,
785 .lock = v9fs_file_lock_dotl,
786 .flock = v9fs_file_flock_dotl,
787 .mmap = generic_file_readonly_mmap,
788 .fsync = v9fs_file_fsync_dotl,
789};