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11#include <linux/module.h>
12#include <linux/errno.h>
13#include <linux/fs.h>
14#include <linux/sched.h>
15#include <linux/file.h>
16#include <linux/stat.h>
17#include <linux/string.h>
18#include <linux/inet.h>
19#include <linux/list.h>
20#include <linux/pagemap.h>
21#include <linux/utsname.h>
22#include <linux/uaccess.h>
23#include <linux/idr.h>
24#include <linux/uio.h>
25#include <linux/slab.h>
26#include <net/9p/9p.h>
27#include <net/9p/client.h>
28
29#include "v9fs.h"
30#include "v9fs_vfs.h"
31#include "fid.h"
32#include "cache.h"
33
34static const struct vm_operations_struct v9fs_file_vm_ops;
35static const struct vm_operations_struct v9fs_mmap_file_vm_ops;
36
37
38
39
40
41
42
43
44int v9fs_file_open(struct inode *inode, struct file *file)
45{
46 int err;
47 struct v9fs_inode *v9inode;
48 struct v9fs_session_info *v9ses;
49 struct p9_fid *fid;
50 int omode;
51
52 p9_debug(P9_DEBUG_VFS, "inode: %p file: %p\n", inode, file);
53 v9inode = V9FS_I(inode);
54 v9ses = v9fs_inode2v9ses(inode);
55 if (v9fs_proto_dotl(v9ses))
56 omode = v9fs_open_to_dotl_flags(file->f_flags);
57 else
58 omode = v9fs_uflags2omode(file->f_flags,
59 v9fs_proto_dotu(v9ses));
60 fid = file->private_data;
61 if (!fid) {
62 fid = v9fs_fid_clone(file_dentry(file));
63 if (IS_ERR(fid))
64 return PTR_ERR(fid);
65
66 err = p9_client_open(fid, omode);
67 if (err < 0) {
68 p9_client_clunk(fid);
69 return err;
70 }
71 if ((file->f_flags & O_APPEND) &&
72 (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)))
73 generic_file_llseek(file, 0, SEEK_END);
74 }
75
76 file->private_data = fid;
77 mutex_lock(&v9inode->v_mutex);
78 if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
79 !v9inode->writeback_fid &&
80 ((file->f_flags & O_ACCMODE) != O_RDONLY)) {
81
82
83
84
85
86
87
88 fid = v9fs_writeback_fid(file_dentry(file));
89 if (IS_ERR(fid)) {
90 err = PTR_ERR(fid);
91 mutex_unlock(&v9inode->v_mutex);
92 goto out_error;
93 }
94 v9inode->writeback_fid = (void *) fid;
95 }
96 mutex_unlock(&v9inode->v_mutex);
97 if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
98 v9fs_cache_inode_set_cookie(inode, file);
99 return 0;
100out_error:
101 p9_client_clunk(file->private_data);
102 file->private_data = NULL;
103 return err;
104}
105
106
107
108
109
110
111
112
113
114
115
116static int v9fs_file_lock(struct file *filp, int cmd, struct file_lock *fl)
117{
118 int res = 0;
119 struct inode *inode = file_inode(filp);
120
121 p9_debug(P9_DEBUG_VFS, "filp: %p lock: %p\n", filp, fl);
122
123
124 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
125 return -ENOLCK;
126
127 if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
128 filemap_write_and_wait(inode->i_mapping);
129 invalidate_mapping_pages(&inode->i_data, 0, -1);
130 }
131
132 return res;
133}
134
135static int v9fs_file_do_lock(struct file *filp, int cmd, struct file_lock *fl)
136{
137 struct p9_flock flock;
138 struct p9_fid *fid;
139 uint8_t status = P9_LOCK_ERROR;
140 int res = 0;
141 unsigned char fl_type;
142 struct v9fs_session_info *v9ses;
143
144 fid = filp->private_data;
145 BUG_ON(fid == NULL);
146
147 if ((fl->fl_flags & FL_POSIX) != FL_POSIX)
148 BUG();
149
150 res = locks_lock_file_wait(filp, fl);
151 if (res < 0)
152 goto out;
153
154
155 memset(&flock, 0, sizeof(flock));
156
157 switch (fl->fl_type) {
158 case F_RDLCK:
159 flock.type = P9_LOCK_TYPE_RDLCK;
160 break;
161 case F_WRLCK:
162 flock.type = P9_LOCK_TYPE_WRLCK;
163 break;
164 case F_UNLCK:
165 flock.type = P9_LOCK_TYPE_UNLCK;
166 break;
167 }
168 flock.start = fl->fl_start;
169 if (fl->fl_end == OFFSET_MAX)
170 flock.length = 0;
171 else
172 flock.length = fl->fl_end - fl->fl_start + 1;
173 flock.proc_id = fl->fl_pid;
174 flock.client_id = fid->clnt->name;
175 if (IS_SETLKW(cmd))
176 flock.flags = P9_LOCK_FLAGS_BLOCK;
177
178 v9ses = v9fs_inode2v9ses(file_inode(filp));
179
180
181
182
183
184 for (;;) {
185 res = p9_client_lock_dotl(fid, &flock, &status);
186 if (res < 0)
187 goto out_unlock;
188
189 if (status != P9_LOCK_BLOCKED)
190 break;
191 if (status == P9_LOCK_BLOCKED && !IS_SETLKW(cmd))
192 break;
193 if (schedule_timeout_interruptible(v9ses->session_lock_timeout)
194 != 0)
195 break;
196
197
198
199
200 if (flock.client_id != fid->clnt->name) {
201 kfree(flock.client_id);
202 flock.client_id = fid->clnt->name;
203 }
204 }
205
206
207 switch (status) {
208 case P9_LOCK_SUCCESS:
209 res = 0;
210 break;
211 case P9_LOCK_BLOCKED:
212 res = -EAGAIN;
213 break;
214 default:
215 WARN_ONCE(1, "unknown lock status code: %d\n", status);
216
217 case P9_LOCK_ERROR:
218 case P9_LOCK_GRACE:
219 res = -ENOLCK;
220 break;
221 }
222
223out_unlock:
224
225
226
227
228 if (res < 0 && fl->fl_type != F_UNLCK) {
229 fl_type = fl->fl_type;
230 fl->fl_type = F_UNLCK;
231
232 locks_lock_file_wait(filp, fl);
233 fl->fl_type = fl_type;
234 }
235 if (flock.client_id != fid->clnt->name)
236 kfree(flock.client_id);
237out:
238 return res;
239}
240
241static int v9fs_file_getlock(struct file *filp, struct file_lock *fl)
242{
243 struct p9_getlock glock;
244 struct p9_fid *fid;
245 int res = 0;
246
247 fid = filp->private_data;
248 BUG_ON(fid == NULL);
249
250 posix_test_lock(filp, fl);
251
252
253
254
255 if (fl->fl_type != F_UNLCK)
256 return res;
257
258
259 memset(&glock, 0, sizeof(glock));
260 glock.type = P9_LOCK_TYPE_UNLCK;
261 glock.start = fl->fl_start;
262 if (fl->fl_end == OFFSET_MAX)
263 glock.length = 0;
264 else
265 glock.length = fl->fl_end - fl->fl_start + 1;
266 glock.proc_id = fl->fl_pid;
267 glock.client_id = fid->clnt->name;
268
269 res = p9_client_getlock_dotl(fid, &glock);
270 if (res < 0)
271 goto out;
272
273 switch (glock.type) {
274 case P9_LOCK_TYPE_RDLCK:
275 fl->fl_type = F_RDLCK;
276 break;
277 case P9_LOCK_TYPE_WRLCK:
278 fl->fl_type = F_WRLCK;
279 break;
280 case P9_LOCK_TYPE_UNLCK:
281 fl->fl_type = F_UNLCK;
282 break;
283 }
284 if (glock.type != P9_LOCK_TYPE_UNLCK) {
285 fl->fl_start = glock.start;
286 if (glock.length == 0)
287 fl->fl_end = OFFSET_MAX;
288 else
289 fl->fl_end = glock.start + glock.length - 1;
290 fl->fl_pid = -glock.proc_id;
291 }
292out:
293 if (glock.client_id != fid->clnt->name)
294 kfree(glock.client_id);
295 return res;
296}
297
298
299
300
301
302
303
304
305
306static int v9fs_file_lock_dotl(struct file *filp, int cmd, struct file_lock *fl)
307{
308 struct inode *inode = file_inode(filp);
309 int ret = -ENOLCK;
310
311 p9_debug(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %pD\n",
312 filp, cmd, fl, filp);
313
314
315 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
316 goto out_err;
317
318 if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
319 filemap_write_and_wait(inode->i_mapping);
320 invalidate_mapping_pages(&inode->i_data, 0, -1);
321 }
322
323 if (IS_SETLK(cmd) || IS_SETLKW(cmd))
324 ret = v9fs_file_do_lock(filp, cmd, fl);
325 else if (IS_GETLK(cmd))
326 ret = v9fs_file_getlock(filp, fl);
327 else
328 ret = -EINVAL;
329out_err:
330 return ret;
331}
332
333
334
335
336
337
338
339
340
341static int v9fs_file_flock_dotl(struct file *filp, int cmd,
342 struct file_lock *fl)
343{
344 struct inode *inode = file_inode(filp);
345 int ret = -ENOLCK;
346
347 p9_debug(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %pD\n",
348 filp, cmd, fl, filp);
349
350
351 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
352 goto out_err;
353
354 if (!(fl->fl_flags & FL_FLOCK))
355 goto out_err;
356
357 if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
358 filemap_write_and_wait(inode->i_mapping);
359 invalidate_mapping_pages(&inode->i_data, 0, -1);
360 }
361
362 fl->fl_flags |= FL_POSIX;
363 fl->fl_flags ^= FL_FLOCK;
364
365 if (IS_SETLK(cmd) | IS_SETLKW(cmd))
366 ret = v9fs_file_do_lock(filp, cmd, fl);
367 else
368 ret = -EINVAL;
369out_err:
370 return ret;
371}
372
373
374
375
376
377
378
379
380
381
382static ssize_t
383v9fs_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
384{
385 struct p9_fid *fid = iocb->ki_filp->private_data;
386 int ret, err = 0;
387
388 p9_debug(P9_DEBUG_VFS, "count %zu offset %lld\n",
389 iov_iter_count(to), iocb->ki_pos);
390
391 ret = p9_client_read(fid, iocb->ki_pos, to, &err);
392 if (!ret)
393 return err;
394
395 iocb->ki_pos += ret;
396 return ret;
397}
398
399
400
401
402
403
404
405
406
407static ssize_t
408v9fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
409{
410 struct file *file = iocb->ki_filp;
411 ssize_t retval;
412 loff_t origin;
413 int err = 0;
414
415 retval = generic_write_checks(iocb, from);
416 if (retval <= 0)
417 return retval;
418
419 origin = iocb->ki_pos;
420 retval = p9_client_write(file->private_data, iocb->ki_pos, from, &err);
421 if (retval > 0) {
422 struct inode *inode = file_inode(file);
423 loff_t i_size;
424 unsigned long pg_start, pg_end;
425 pg_start = origin >> PAGE_SHIFT;
426 pg_end = (origin + retval - 1) >> PAGE_SHIFT;
427 if (inode->i_mapping && inode->i_mapping->nrpages)
428 invalidate_inode_pages2_range(inode->i_mapping,
429 pg_start, pg_end);
430 iocb->ki_pos += retval;
431 i_size = i_size_read(inode);
432 if (iocb->ki_pos > i_size) {
433 inode_add_bytes(inode, iocb->ki_pos - i_size);
434
435
436
437
438 v9fs_i_size_write(inode, iocb->ki_pos);
439 }
440 return retval;
441 }
442 return err;
443}
444
445static int v9fs_file_fsync(struct file *filp, loff_t start, loff_t end,
446 int datasync)
447{
448 struct p9_fid *fid;
449 struct inode *inode = filp->f_mapping->host;
450 struct p9_wstat wstat;
451 int retval;
452
453 retval = file_write_and_wait_range(filp, start, end);
454 if (retval)
455 return retval;
456
457 inode_lock(inode);
458 p9_debug(P9_DEBUG_VFS, "filp %p datasync %x\n", filp, datasync);
459
460 fid = filp->private_data;
461 v9fs_blank_wstat(&wstat);
462
463 retval = p9_client_wstat(fid, &wstat);
464 inode_unlock(inode);
465
466 return retval;
467}
468
469int v9fs_file_fsync_dotl(struct file *filp, loff_t start, loff_t end,
470 int datasync)
471{
472 struct p9_fid *fid;
473 struct inode *inode = filp->f_mapping->host;
474 int retval;
475
476 retval = file_write_and_wait_range(filp, start, end);
477 if (retval)
478 return retval;
479
480 inode_lock(inode);
481 p9_debug(P9_DEBUG_VFS, "filp %p datasync %x\n", filp, datasync);
482
483 fid = filp->private_data;
484
485 retval = p9_client_fsync(fid, datasync);
486 inode_unlock(inode);
487
488 return retval;
489}
490
491static int
492v9fs_file_mmap(struct file *filp, struct vm_area_struct *vma)
493{
494 int retval;
495
496
497 retval = generic_file_mmap(filp, vma);
498 if (!retval)
499 vma->vm_ops = &v9fs_file_vm_ops;
500
501 return retval;
502}
503
504static int
505v9fs_mmap_file_mmap(struct file *filp, struct vm_area_struct *vma)
506{
507 int retval;
508 struct inode *inode;
509 struct v9fs_inode *v9inode;
510 struct p9_fid *fid;
511
512 inode = file_inode(filp);
513 v9inode = V9FS_I(inode);
514 mutex_lock(&v9inode->v_mutex);
515 if (!v9inode->writeback_fid &&
516 (vma->vm_flags & VM_WRITE)) {
517
518
519
520
521
522
523
524 fid = v9fs_writeback_fid(file_dentry(filp));
525 if (IS_ERR(fid)) {
526 retval = PTR_ERR(fid);
527 mutex_unlock(&v9inode->v_mutex);
528 return retval;
529 }
530 v9inode->writeback_fid = (void *) fid;
531 }
532 mutex_unlock(&v9inode->v_mutex);
533
534 retval = generic_file_mmap(filp, vma);
535 if (!retval)
536 vma->vm_ops = &v9fs_mmap_file_vm_ops;
537
538 return retval;
539}
540
541static vm_fault_t
542v9fs_vm_page_mkwrite(struct vm_fault *vmf)
543{
544 struct v9fs_inode *v9inode;
545 struct page *page = vmf->page;
546 struct file *filp = vmf->vma->vm_file;
547 struct inode *inode = file_inode(filp);
548
549
550 p9_debug(P9_DEBUG_VFS, "page %p fid %lx\n",
551 page, (unsigned long)filp->private_data);
552
553
554 file_update_time(filp);
555
556 v9inode = V9FS_I(inode);
557
558 v9fs_fscache_wait_on_page_write(inode, page);
559 BUG_ON(!v9inode->writeback_fid);
560 lock_page(page);
561 if (page->mapping != inode->i_mapping)
562 goto out_unlock;
563 wait_for_stable_page(page);
564
565 return VM_FAULT_LOCKED;
566out_unlock:
567 unlock_page(page);
568 return VM_FAULT_NOPAGE;
569}
570
571
572
573
574
575
576
577
578
579static ssize_t
580v9fs_mmap_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
581{
582
583 return v9fs_file_read_iter(iocb, to);
584}
585
586
587
588
589
590
591
592
593
594static ssize_t
595v9fs_mmap_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
596{
597
598
599
600
601 return v9fs_file_write_iter(iocb, from);
602}
603
604static void v9fs_mmap_vm_close(struct vm_area_struct *vma)
605{
606 struct inode *inode;
607
608 struct writeback_control wbc = {
609 .nr_to_write = LONG_MAX,
610 .sync_mode = WB_SYNC_ALL,
611 .range_start = vma->vm_pgoff * PAGE_SIZE,
612
613 .range_end = vma->vm_pgoff * PAGE_SIZE +
614 (vma->vm_end - vma->vm_start - 1),
615 };
616
617
618 p9_debug(P9_DEBUG_VFS, "9p VMA close, %p, flushing", vma);
619
620 inode = file_inode(vma->vm_file);
621
622 if (!mapping_cap_writeback_dirty(inode->i_mapping))
623 wbc.nr_to_write = 0;
624
625 might_sleep();
626 sync_inode(inode, &wbc);
627}
628
629
630static const struct vm_operations_struct v9fs_file_vm_ops = {
631 .fault = filemap_fault,
632 .map_pages = filemap_map_pages,
633 .page_mkwrite = v9fs_vm_page_mkwrite,
634};
635
636static const struct vm_operations_struct v9fs_mmap_file_vm_ops = {
637 .close = v9fs_mmap_vm_close,
638 .fault = filemap_fault,
639 .map_pages = filemap_map_pages,
640 .page_mkwrite = v9fs_vm_page_mkwrite,
641};
642
643
644const struct file_operations v9fs_cached_file_operations = {
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,
651 .mmap = v9fs_file_mmap,
652 .fsync = v9fs_file_fsync,
653};
654
655const struct file_operations v9fs_cached_file_operations_dotl = {
656 .llseek = generic_file_llseek,
657 .read_iter = generic_file_read_iter,
658 .write_iter = generic_file_write_iter,
659 .open = v9fs_file_open,
660 .release = v9fs_dir_release,
661 .lock = v9fs_file_lock_dotl,
662 .flock = v9fs_file_flock_dotl,
663 .mmap = v9fs_file_mmap,
664 .fsync = v9fs_file_fsync_dotl,
665};
666
667const struct file_operations v9fs_file_operations = {
668 .llseek = generic_file_llseek,
669 .read_iter = v9fs_file_read_iter,
670 .write_iter = v9fs_file_write_iter,
671 .open = v9fs_file_open,
672 .release = v9fs_dir_release,
673 .lock = v9fs_file_lock,
674 .mmap = generic_file_readonly_mmap,
675 .fsync = v9fs_file_fsync,
676};
677
678const struct file_operations v9fs_file_operations_dotl = {
679 .llseek = generic_file_llseek,
680 .read_iter = v9fs_file_read_iter,
681 .write_iter = v9fs_file_write_iter,
682 .open = v9fs_file_open,
683 .release = v9fs_dir_release,
684 .lock = v9fs_file_lock_dotl,
685 .flock = v9fs_file_flock_dotl,
686 .mmap = generic_file_readonly_mmap,
687 .fsync = v9fs_file_fsync_dotl,
688};
689
690const struct file_operations v9fs_mmap_file_operations = {
691 .llseek = generic_file_llseek,
692 .read_iter = v9fs_mmap_file_read_iter,
693 .write_iter = v9fs_mmap_file_write_iter,
694 .open = v9fs_file_open,
695 .release = v9fs_dir_release,
696 .lock = v9fs_file_lock,
697 .mmap = v9fs_mmap_file_mmap,
698 .fsync = v9fs_file_fsync,
699};
700
701const struct file_operations v9fs_mmap_file_operations_dotl = {
702 .llseek = generic_file_llseek,
703 .read_iter = v9fs_mmap_file_read_iter,
704 .write_iter = v9fs_mmap_file_write_iter,
705 .open = v9fs_file_open,
706 .release = v9fs_dir_release,
707 .lock = v9fs_file_lock_dotl,
708 .flock = v9fs_file_flock_dotl,
709 .mmap = v9fs_mmap_file_mmap,
710 .fsync = v9fs_file_fsync_dotl,
711};
712
