vfs: switch ->show_options() to struct dentry *
[deliverable/linux.git] / drivers / staging / pohmelfs / inode.c
1 /*
2 * 2007+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net>
3 * All rights reserved.
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 */
15
16 #include <linux/module.h>
17 #include <linux/backing-dev.h>
18 #include <linux/crypto.h>
19 #include <linux/fs.h>
20 #include <linux/jhash.h>
21 #include <linux/hash.h>
22 #include <linux/ktime.h>
23 #include <linux/mm.h>
24 #include <linux/mount.h>
25 #include <linux/pagemap.h>
26 #include <linux/pagevec.h>
27 #include <linux/parser.h>
28 #include <linux/swap.h>
29 #include <linux/slab.h>
30 #include <linux/statfs.h>
31 #include <linux/writeback.h>
32 #include <linux/prefetch.h>
33
34 #include "netfs.h"
35
36 #define POHMELFS_MAGIC_NUM 0x504f482e
37
38 static struct kmem_cache *pohmelfs_inode_cache;
39 static atomic_t psb_bdi_num = ATOMIC_INIT(0);
40
41 /*
42 * Removes inode from all trees, drops local name cache and removes all queued
43 * requests for object removal.
44 */
45 void pohmelfs_inode_del_inode(struct pohmelfs_sb *psb, struct pohmelfs_inode *pi)
46 {
47 mutex_lock(&pi->offset_lock);
48 pohmelfs_free_names(pi);
49 mutex_unlock(&pi->offset_lock);
50
51 dprintk("%s: deleted stuff in ino: %llu.\n", __func__, pi->ino);
52 }
53
54 /*
55 * Sync inode to server.
56 * Returns zero in success and negative error value otherwise.
57 * It will gather path to root directory into structures containing
58 * creation mode, permissions and names, so that the whole path
59 * to given inode could be created using only single network command.
60 */
61 int pohmelfs_write_inode_create(struct inode *inode, struct netfs_trans *trans)
62 {
63 struct pohmelfs_inode *pi = POHMELFS_I(inode);
64 int err = -ENOMEM, size;
65 struct netfs_cmd *cmd;
66 void *data;
67 int cur_len = netfs_trans_cur_len(trans);
68
69 if (unlikely(cur_len < 0))
70 return -ETOOSMALL;
71
72 cmd = netfs_trans_current(trans);
73 cur_len -= sizeof(struct netfs_cmd);
74
75 data = (void *)(cmd + 1);
76
77 err = pohmelfs_construct_path_string(pi, data, cur_len);
78 if (err < 0)
79 goto err_out_exit;
80
81 size = err;
82
83 cmd->start = i_size_read(inode);
84 cmd->cmd = NETFS_CREATE;
85 cmd->size = size;
86 cmd->id = pi->ino;
87 cmd->ext = inode->i_mode;
88
89 netfs_convert_cmd(cmd);
90
91 netfs_trans_update(cmd, trans, size);
92
93 return 0;
94
95 err_out_exit:
96 printk("%s: completed ino: %llu, err: %d.\n", __func__, pi->ino, err);
97 return err;
98 }
99
100 static int pohmelfs_write_trans_complete(struct page **pages, unsigned int page_num,
101 void *private, int err)
102 {
103 unsigned i;
104
105 dprintk("%s: pages: %lu-%lu, page_num: %u, err: %d.\n",
106 __func__, pages[0]->index, pages[page_num-1]->index,
107 page_num, err);
108
109 for (i = 0; i < page_num; i++) {
110 struct page *page = pages[i];
111
112 if (!page)
113 continue;
114
115 end_page_writeback(page);
116
117 if (err < 0) {
118 SetPageError(page);
119 set_page_dirty(page);
120 }
121
122 unlock_page(page);
123 page_cache_release(page);
124
125 /* dprintk("%s: %3u/%u: page: %p.\n", __func__, i, page_num, page); */
126 }
127 return err;
128 }
129
130 static int pohmelfs_inode_has_dirty_pages(struct address_space *mapping, pgoff_t index)
131 {
132 int ret;
133 struct page *page;
134
135 rcu_read_lock();
136 ret = radix_tree_gang_lookup_tag(&mapping->page_tree,
137 (void **)&page, index, 1, PAGECACHE_TAG_DIRTY);
138 rcu_read_unlock();
139 return ret;
140 }
141
142 static int pohmelfs_writepages(struct address_space *mapping, struct writeback_control *wbc)
143 {
144 struct inode *inode = mapping->host;
145 struct pohmelfs_inode *pi = POHMELFS_I(inode);
146 struct pohmelfs_sb *psb = POHMELFS_SB(inode->i_sb);
147 int err = 0;
148 int done = 0;
149 int nr_pages;
150 pgoff_t index;
151 pgoff_t end; /* Inclusive */
152 int scanned = 0;
153 int range_whole = 0;
154
155 if (wbc->range_cyclic) {
156 index = mapping->writeback_index; /* Start from prev offset */
157 end = -1;
158 } else {
159 index = wbc->range_start >> PAGE_CACHE_SHIFT;
160 end = wbc->range_end >> PAGE_CACHE_SHIFT;
161 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
162 range_whole = 1;
163 scanned = 1;
164 }
165 retry:
166 while (!done && (index <= end)) {
167 unsigned int i = min(end - index, (pgoff_t)psb->trans_max_pages);
168 int path_len;
169 struct netfs_trans *trans;
170
171 err = pohmelfs_inode_has_dirty_pages(mapping, index);
172 if (!err)
173 break;
174
175 err = pohmelfs_path_length(pi);
176 if (err < 0)
177 break;
178
179 path_len = err;
180
181 if (path_len <= 2) {
182 err = -ENOENT;
183 break;
184 }
185
186 trans = netfs_trans_alloc(psb, path_len, 0, i);
187 if (!trans) {
188 err = -ENOMEM;
189 break;
190 }
191 trans->complete = &pohmelfs_write_trans_complete;
192
193 trans->page_num = nr_pages = find_get_pages_tag(mapping, &index,
194 PAGECACHE_TAG_DIRTY, trans->page_num,
195 trans->pages);
196
197 dprintk("%s: t: %p, nr_pages: %u, end: %lu, index: %lu, max: %u.\n",
198 __func__, trans, nr_pages, end, index, trans->page_num);
199
200 if (!nr_pages)
201 goto err_out_reset;
202
203 err = pohmelfs_write_inode_create(inode, trans);
204 if (err)
205 goto err_out_reset;
206
207 err = 0;
208 scanned = 1;
209
210 for (i = 0; i < trans->page_num; i++) {
211 struct page *page = trans->pages[i];
212
213 lock_page(page);
214
215 if (unlikely(page->mapping != mapping))
216 goto out_continue;
217
218 if (!wbc->range_cyclic && page->index > end) {
219 done = 1;
220 goto out_continue;
221 }
222
223 if (wbc->sync_mode != WB_SYNC_NONE)
224 wait_on_page_writeback(page);
225
226 if (PageWriteback(page) ||
227 !clear_page_dirty_for_io(page)) {
228 dprintk("%s: not clear for io page: %p, writeback: %d.\n",
229 __func__, page, PageWriteback(page));
230 goto out_continue;
231 }
232
233 set_page_writeback(page);
234
235 trans->attached_size += page_private(page);
236 trans->attached_pages++;
237 #if 0
238 dprintk("%s: %u/%u added trans: %p, gen: %u, page: %p, [High: %d], size: %lu, idx: %lu.\n",
239 __func__, i, trans->page_num, trans, trans->gen, page,
240 !!PageHighMem(page), page_private(page), page->index);
241 #endif
242 wbc->nr_to_write--;
243
244 if (wbc->nr_to_write <= 0)
245 done = 1;
246
247 continue;
248 out_continue:
249 unlock_page(page);
250 trans->pages[i] = NULL;
251 }
252
253 err = netfs_trans_finish(trans, psb);
254 if (err)
255 break;
256
257 continue;
258
259 err_out_reset:
260 trans->result = err;
261 netfs_trans_reset(trans);
262 netfs_trans_put(trans);
263 break;
264 }
265
266 if (!scanned && !done) {
267 /*
268 * We hit the last page and there is more work to be done: wrap
269 * back to the start of the file
270 */
271 scanned = 1;
272 index = 0;
273 goto retry;
274 }
275
276 if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
277 mapping->writeback_index = index;
278
279 return err;
280 }
281
282 /*
283 * Inode writeback creation completion callback.
284 * Only invoked for just created inodes, which do not have pages attached,
285 * like dirs and empty files.
286 */
287 static int pohmelfs_write_inode_complete(struct page **pages, unsigned int page_num,
288 void *private, int err)
289 {
290 struct inode *inode = private;
291 struct pohmelfs_inode *pi = POHMELFS_I(inode);
292
293 if (inode) {
294 if (err) {
295 mark_inode_dirty(inode);
296 clear_bit(NETFS_INODE_REMOTE_SYNCED, &pi->state);
297 } else {
298 set_bit(NETFS_INODE_REMOTE_SYNCED, &pi->state);
299 }
300
301 pohmelfs_put_inode(pi);
302 }
303
304 return err;
305 }
306
307 int pohmelfs_write_create_inode(struct pohmelfs_inode *pi)
308 {
309 struct netfs_trans *t;
310 struct inode *inode = &pi->vfs_inode;
311 struct pohmelfs_sb *psb = POHMELFS_SB(inode->i_sb);
312 int err;
313
314 if (test_bit(NETFS_INODE_REMOTE_SYNCED, &pi->state))
315 return 0;
316
317 dprintk("%s: started ino: %llu.\n", __func__, pi->ino);
318
319 err = pohmelfs_path_length(pi);
320 if (err < 0)
321 goto err_out_exit;
322
323 t = netfs_trans_alloc(psb, err + 1, 0, 0);
324 if (!t) {
325 err = -ENOMEM;
326 goto err_out_exit;
327 }
328 t->complete = pohmelfs_write_inode_complete;
329 t->private = igrab(inode);
330 if (!t->private) {
331 err = -ENOENT;
332 goto err_out_put;
333 }
334
335 err = pohmelfs_write_inode_create(inode, t);
336 if (err)
337 goto err_out_put;
338
339 netfs_trans_finish(t, POHMELFS_SB(inode->i_sb));
340
341 return 0;
342
343 err_out_put:
344 t->result = err;
345 netfs_trans_put(t);
346 err_out_exit:
347 return err;
348 }
349
350 /*
351 * Sync all not-yet-created children in given directory to the server.
352 */
353 static int pohmelfs_write_inode_create_children(struct inode *inode)
354 {
355 struct pohmelfs_inode *parent = POHMELFS_I(inode);
356 struct super_block *sb = inode->i_sb;
357 struct pohmelfs_name *n;
358
359 while (!list_empty(&parent->sync_create_list)) {
360 n = NULL;
361 mutex_lock(&parent->offset_lock);
362 if (!list_empty(&parent->sync_create_list)) {
363 n = list_first_entry(&parent->sync_create_list,
364 struct pohmelfs_name, sync_create_entry);
365 list_del_init(&n->sync_create_entry);
366 }
367 mutex_unlock(&parent->offset_lock);
368
369 if (!n)
370 break;
371
372 inode = ilookup(sb, n->ino);
373
374 dprintk("%s: parent: %llu, ino: %llu, inode: %p.\n",
375 __func__, parent->ino, n->ino, inode);
376
377 if (inode && (inode->i_state & I_DIRTY)) {
378 struct pohmelfs_inode *pi = POHMELFS_I(inode);
379 pohmelfs_write_create_inode(pi);
380 /* pohmelfs_meta_command(pi, NETFS_INODE_INFO, 0, NULL, NULL, 0); */
381 iput(inode);
382 }
383 }
384
385 return 0;
386 }
387
388 /*
389 * Removes given child from given inode on server.
390 */
391 int pohmelfs_remove_child(struct pohmelfs_inode *pi, struct pohmelfs_name *n)
392 {
393 return pohmelfs_meta_command_data(pi, pi->ino, NETFS_REMOVE, NULL, 0, NULL, NULL, 0);
394 }
395
396 /*
397 * Writeback for given inode.
398 */
399 static int pohmelfs_write_inode(struct inode *inode,
400 struct writeback_control *wbc)
401 {
402 struct pohmelfs_inode *pi = POHMELFS_I(inode);
403
404 pohmelfs_write_create_inode(pi);
405 pohmelfs_write_inode_create_children(inode);
406
407 return 0;
408 }
409
410 /*
411 * It is not exported, sorry...
412 */
413 static inline wait_queue_head_t *page_waitqueue(struct page *page)
414 {
415 const struct zone *zone = page_zone(page);
416
417 return &zone->wait_table[hash_ptr(page, zone->wait_table_bits)];
418 }
419
420 static int pohmelfs_wait_on_page_locked(struct page *page)
421 {
422 struct pohmelfs_sb *psb = POHMELFS_SB(page->mapping->host->i_sb);
423 long ret = psb->wait_on_page_timeout;
424 DEFINE_WAIT_BIT(wait, &page->flags, PG_locked);
425 int err = 0;
426
427 if (!PageLocked(page))
428 return 0;
429
430 for (;;) {
431 prepare_to_wait(page_waitqueue(page),
432 &wait.wait, TASK_INTERRUPTIBLE);
433
434 dprintk("%s: page: %p, locked: %d, uptodate: %d, error: %d, flags: %lx.\n",
435 __func__, page, PageLocked(page), PageUptodate(page),
436 PageError(page), page->flags);
437
438 if (!PageLocked(page))
439 break;
440
441 if (!signal_pending(current)) {
442 ret = schedule_timeout(ret);
443 if (!ret)
444 break;
445 continue;
446 }
447 ret = -ERESTARTSYS;
448 break;
449 }
450 finish_wait(page_waitqueue(page), &wait.wait);
451
452 if (!ret)
453 err = -ETIMEDOUT;
454
455
456 if (!err)
457 SetPageUptodate(page);
458
459 if (err)
460 printk("%s: page: %p, uptodate: %d, locked: %d, err: %d.\n",
461 __func__, page, PageUptodate(page), PageLocked(page), err);
462
463 return err;
464 }
465
466 static int pohmelfs_read_page_complete(struct page **pages, unsigned int page_num,
467 void *private, int err)
468 {
469 struct page *page = private;
470
471 if (PageChecked(page))
472 return err;
473
474 if (err < 0) {
475 dprintk("%s: page: %p, err: %d.\n", __func__, page, err);
476 SetPageError(page);
477 }
478
479 unlock_page(page);
480
481 return err;
482 }
483
484 /*
485 * Read a page from remote server.
486 * Function will wait until page is unlocked.
487 */
488 static int pohmelfs_readpage(struct file *file, struct page *page)
489 {
490 struct inode *inode = page->mapping->host;
491 struct pohmelfs_sb *psb = POHMELFS_SB(inode->i_sb);
492 struct pohmelfs_inode *pi = POHMELFS_I(inode);
493 struct netfs_trans *t;
494 struct netfs_cmd *cmd;
495 int err, path_len;
496 void *data;
497 u64 isize;
498
499 err = pohmelfs_data_lock(pi, page->index << PAGE_CACHE_SHIFT,
500 PAGE_SIZE, POHMELFS_READ_LOCK);
501 if (err)
502 goto err_out_exit;
503
504 isize = i_size_read(inode);
505 if (isize <= page->index << PAGE_CACHE_SHIFT) {
506 SetPageUptodate(page);
507 unlock_page(page);
508 return 0;
509 }
510
511 path_len = pohmelfs_path_length(pi);
512 if (path_len < 0) {
513 err = path_len;
514 goto err_out_exit;
515 }
516
517 t = netfs_trans_alloc(psb, path_len, NETFS_TRANS_SINGLE_DST, 0);
518 if (!t) {
519 err = -ENOMEM;
520 goto err_out_exit;
521 }
522
523 t->complete = pohmelfs_read_page_complete;
524 t->private = page;
525
526 cmd = netfs_trans_current(t);
527 data = (void *)(cmd + 1);
528
529 err = pohmelfs_construct_path_string(pi, data, path_len);
530 if (err < 0)
531 goto err_out_free;
532
533 path_len = err;
534
535 cmd->id = pi->ino;
536 cmd->start = page->index;
537 cmd->start <<= PAGE_CACHE_SHIFT;
538 cmd->size = PAGE_CACHE_SIZE + path_len;
539 cmd->cmd = NETFS_READ_PAGE;
540 cmd->ext = path_len;
541
542 dprintk("%s: path: '%s', page: %p, ino: %llu, start: %llu, size: %lu.\n",
543 __func__, (char *)data, page, pi->ino, cmd->start, PAGE_CACHE_SIZE);
544
545 netfs_convert_cmd(cmd);
546 netfs_trans_update(cmd, t, path_len);
547
548 err = netfs_trans_finish(t, psb);
549 if (err)
550 goto err_out_return;
551
552 return pohmelfs_wait_on_page_locked(page);
553
554 err_out_free:
555 t->result = err;
556 netfs_trans_put(t);
557 err_out_exit:
558 SetPageError(page);
559 if (PageLocked(page))
560 unlock_page(page);
561 err_out_return:
562 printk("%s: page: %p, start: %lu, size: %lu, err: %d.\n",
563 __func__, page, page->index << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE, err);
564
565 return err;
566 }
567
568 /*
569 * Write begin/end magic.
570 * Allocates a page and writes inode if it was not synced to server before.
571 */
572 static int pohmelfs_write_begin(struct file *file, struct address_space *mapping,
573 loff_t pos, unsigned len, unsigned flags,
574 struct page **pagep, void **fsdata)
575 {
576 struct inode *inode = mapping->host;
577 struct page *page;
578 pgoff_t index;
579 unsigned start, end;
580 int err;
581
582 *pagep = NULL;
583
584 index = pos >> PAGE_CACHE_SHIFT;
585 start = pos & (PAGE_CACHE_SIZE - 1);
586 end = start + len;
587
588 page = grab_cache_page(mapping, index);
589 #if 0
590 dprintk("%s: page: %p pos: %llu, len: %u, index: %lu, start: %u, end: %u, uptodate: %d.\n",
591 __func__, page, pos, len, index, start, end, PageUptodate(page));
592 #endif
593 if (!page) {
594 err = -ENOMEM;
595 goto err_out_exit;
596 }
597
598 while (!PageUptodate(page)) {
599 if (start && test_bit(NETFS_INODE_REMOTE_SYNCED, &POHMELFS_I(inode)->state)) {
600 err = pohmelfs_readpage(file, page);
601 if (err)
602 goto err_out_exit;
603
604 lock_page(page);
605 continue;
606 }
607
608 if (len != PAGE_CACHE_SIZE) {
609 void *kaddr = kmap_atomic(page, KM_USER0);
610
611 memset(kaddr + start, 0, PAGE_CACHE_SIZE - start);
612 flush_dcache_page(page);
613 kunmap_atomic(kaddr, KM_USER0);
614 }
615 SetPageUptodate(page);
616 }
617
618 set_page_private(page, end);
619
620 *pagep = page;
621
622 return 0;
623
624 err_out_exit:
625 page_cache_release(page);
626 *pagep = NULL;
627
628 return err;
629 }
630
631 static int pohmelfs_write_end(struct file *file, struct address_space *mapping,
632 loff_t pos, unsigned len, unsigned copied,
633 struct page *page, void *fsdata)
634 {
635 struct inode *inode = mapping->host;
636
637 if (copied != len) {
638 unsigned from = pos & (PAGE_CACHE_SIZE - 1);
639 void *kaddr = kmap_atomic(page, KM_USER0);
640
641 memset(kaddr + from + copied, 0, len - copied);
642 flush_dcache_page(page);
643 kunmap_atomic(kaddr, KM_USER0);
644 }
645
646 SetPageUptodate(page);
647 set_page_dirty(page);
648 #if 0
649 dprintk("%s: page: %p [U: %d, D: %d, L: %d], pos: %llu, len: %u, copied: %u.\n",
650 __func__, page,
651 PageUptodate(page), PageDirty(page), PageLocked(page),
652 pos, len, copied);
653 #endif
654 flush_dcache_page(page);
655
656 unlock_page(page);
657 page_cache_release(page);
658
659 if (pos + copied > inode->i_size) {
660 struct pohmelfs_sb *psb = POHMELFS_SB(inode->i_sb);
661
662 psb->avail_size -= pos + copied - inode->i_size;
663
664 i_size_write(inode, pos + copied);
665 }
666
667 return copied;
668 }
669
670 static int pohmelfs_readpages_trans_complete(struct page **__pages, unsigned int page_num,
671 void *private, int err)
672 {
673 struct pohmelfs_inode *pi = private;
674 unsigned int i, num;
675 struct page **pages, *page = (struct page *)__pages;
676 loff_t index = page->index;
677
678 pages = kzalloc(sizeof(void *) * page_num, GFP_NOIO);
679 if (!pages)
680 return -ENOMEM;
681
682 num = find_get_pages_contig(pi->vfs_inode.i_mapping, index, page_num, pages);
683 if (num <= 0) {
684 err = num;
685 goto err_out_free;
686 }
687
688 for (i = 0; i < num; ++i) {
689 page = pages[i];
690
691 if (err)
692 printk("%s: %u/%u: page: %p, index: %lu, uptodate: %d, locked: %d, err: %d.\n",
693 __func__, i, num, page, page->index,
694 PageUptodate(page), PageLocked(page), err);
695
696 if (!PageChecked(page)) {
697 if (err < 0)
698 SetPageError(page);
699 unlock_page(page);
700 }
701 page_cache_release(page);
702 page_cache_release(page);
703 }
704
705 err_out_free:
706 kfree(pages);
707 return err;
708 }
709
710 static int pohmelfs_send_readpages(struct pohmelfs_inode *pi, struct page *first, unsigned int num)
711 {
712 struct netfs_trans *t;
713 struct netfs_cmd *cmd;
714 struct pohmelfs_sb *psb = POHMELFS_SB(pi->vfs_inode.i_sb);
715 int err, path_len;
716 void *data;
717
718 err = pohmelfs_data_lock(pi, first->index << PAGE_CACHE_SHIFT,
719 num * PAGE_SIZE, POHMELFS_READ_LOCK);
720 if (err)
721 goto err_out_exit;
722
723 path_len = pohmelfs_path_length(pi);
724 if (path_len < 0) {
725 err = path_len;
726 goto err_out_exit;
727 }
728
729 t = netfs_trans_alloc(psb, path_len, NETFS_TRANS_SINGLE_DST, 0);
730 if (!t) {
731 err = -ENOMEM;
732 goto err_out_exit;
733 }
734
735 cmd = netfs_trans_current(t);
736 data = (void *)(cmd + 1);
737
738 t->complete = pohmelfs_readpages_trans_complete;
739 t->private = pi;
740 t->page_num = num;
741 t->pages = (struct page **)first;
742
743 err = pohmelfs_construct_path_string(pi, data, path_len);
744 if (err < 0)
745 goto err_out_put;
746
747 path_len = err;
748
749 cmd->cmd = NETFS_READ_PAGES;
750 cmd->start = first->index;
751 cmd->start <<= PAGE_CACHE_SHIFT;
752 cmd->size = (num << 8 | PAGE_CACHE_SHIFT);
753 cmd->id = pi->ino;
754 cmd->ext = path_len;
755
756 dprintk("%s: t: %p, gen: %u, path: '%s', path_len: %u, "
757 "start: %lu, num: %u.\n",
758 __func__, t, t->gen, (char *)data, path_len,
759 first->index, num);
760
761 netfs_convert_cmd(cmd);
762 netfs_trans_update(cmd, t, path_len);
763
764 return netfs_trans_finish(t, psb);
765
766 err_out_put:
767 netfs_trans_free(t);
768 err_out_exit:
769 pohmelfs_readpages_trans_complete((struct page **)first, num, pi, err);
770 return err;
771 }
772
773 #define list_to_page(head) (list_entry((head)->prev, struct page, lru))
774
775 static int pohmelfs_readpages(struct file *file, struct address_space *mapping,
776 struct list_head *pages, unsigned nr_pages)
777 {
778 unsigned int page_idx, num = 0;
779 struct page *page = NULL, *first = NULL;
780
781 for (page_idx = 0; page_idx < nr_pages; page_idx++) {
782 page = list_to_page(pages);
783
784 prefetchw(&page->flags);
785 list_del(&page->lru);
786
787 if (!add_to_page_cache_lru(page, mapping,
788 page->index, GFP_KERNEL)) {
789
790 if (!num) {
791 num = 1;
792 first = page;
793 continue;
794 }
795
796 dprintk("%s: added to lru page: %p, page_index: %lu, first_index: %lu.\n",
797 __func__, page, page->index, first->index);
798
799 if (unlikely(first->index + num != page->index) || (num > 500)) {
800 pohmelfs_send_readpages(POHMELFS_I(mapping->host),
801 first, num);
802 first = page;
803 num = 0;
804 }
805
806 num++;
807 }
808 }
809 pohmelfs_send_readpages(POHMELFS_I(mapping->host), first, num);
810
811 /*
812 * This will be sync read, so when last page is processed,
813 * all previous are alerady unlocked and ready to be used.
814 */
815 return 0;
816 }
817
818 /*
819 * Small address space operations for POHMELFS.
820 */
821 const struct address_space_operations pohmelfs_aops = {
822 .readpage = pohmelfs_readpage,
823 .readpages = pohmelfs_readpages,
824 .writepages = pohmelfs_writepages,
825 .write_begin = pohmelfs_write_begin,
826 .write_end = pohmelfs_write_end,
827 .set_page_dirty = __set_page_dirty_nobuffers,
828 };
829
830 static void pohmelfs_i_callback(struct rcu_head *head)
831 {
832 struct inode *inode = container_of(head, struct inode, i_rcu);
833 kmem_cache_free(pohmelfs_inode_cache, POHMELFS_I(inode));
834 }
835
836 /*
837 * ->destroy_inode() callback. Deletes inode from the caches
838 * and frees private data.
839 */
840 static void pohmelfs_destroy_inode(struct inode *inode)
841 {
842 struct super_block *sb = inode->i_sb;
843 struct pohmelfs_sb *psb = POHMELFS_SB(sb);
844 struct pohmelfs_inode *pi = POHMELFS_I(inode);
845
846 /* pohmelfs_data_unlock(pi, 0, inode->i_size, POHMELFS_READ_LOCK); */
847
848 pohmelfs_inode_del_inode(psb, pi);
849
850 dprintk("%s: pi: %p, inode: %p, ino: %llu.\n",
851 __func__, pi, &pi->vfs_inode, pi->ino);
852 atomic_long_dec(&psb->total_inodes);
853 call_rcu(&inode->i_rcu, pohmelfs_i_callback);
854 }
855
856 /*
857 * ->alloc_inode() callback. Allocates inode and initializes private data.
858 */
859 static struct inode *pohmelfs_alloc_inode(struct super_block *sb)
860 {
861 struct pohmelfs_inode *pi;
862
863 pi = kmem_cache_alloc(pohmelfs_inode_cache, GFP_NOIO);
864 if (!pi)
865 return NULL;
866
867 pi->hash_root = RB_ROOT;
868 mutex_init(&pi->offset_lock);
869
870 INIT_LIST_HEAD(&pi->sync_create_list);
871
872 INIT_LIST_HEAD(&pi->inode_entry);
873
874 pi->lock_type = 0;
875 pi->state = 0;
876 pi->total_len = 0;
877 pi->drop_count = 0;
878
879 dprintk("%s: pi: %p, inode: %p.\n", __func__, pi, &pi->vfs_inode);
880
881 atomic_long_inc(&POHMELFS_SB(sb)->total_inodes);
882
883 return &pi->vfs_inode;
884 }
885
886 /*
887 * We want fsync() to work on POHMELFS.
888 */
889 static int pohmelfs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
890 {
891 struct inode *inode = file->f_mapping->host;
892 int err = filemap_write_and_wait_range(inode->i_mapping, start, end);
893 if (!err) {
894 mutex_lock(&inode->i_mutex);
895 err = sync_inode_metadata(inode, 1);
896 mutex_unlock(&inode->i_mutex);
897 }
898 return err;
899 }
900
901 ssize_t pohmelfs_write(struct file *file, const char __user *buf,
902 size_t len, loff_t *ppos)
903 {
904 struct address_space *mapping = file->f_mapping;
905 struct inode *inode = mapping->host;
906 struct pohmelfs_inode *pi = POHMELFS_I(inode);
907 struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len };
908 struct kiocb kiocb;
909 ssize_t ret;
910 loff_t pos = *ppos;
911
912 init_sync_kiocb(&kiocb, file);
913 kiocb.ki_pos = pos;
914 kiocb.ki_left = len;
915
916 dprintk("%s: len: %zu, pos: %llu.\n", __func__, len, pos);
917
918 mutex_lock(&inode->i_mutex);
919 ret = pohmelfs_data_lock(pi, pos, len, POHMELFS_WRITE_LOCK);
920 if (ret)
921 goto err_out_unlock;
922
923 ret = __generic_file_aio_write(&kiocb, &iov, 1, &kiocb.ki_pos);
924 *ppos = kiocb.ki_pos;
925
926 mutex_unlock(&inode->i_mutex);
927 WARN_ON(ret < 0);
928
929 if (ret > 0) {
930 ssize_t err;
931
932 err = generic_write_sync(file, pos, ret);
933 if (err < 0)
934 ret = err;
935 WARN_ON(ret < 0);
936 }
937
938 return ret;
939
940 err_out_unlock:
941 mutex_unlock(&inode->i_mutex);
942 return ret;
943 }
944
945 static const struct file_operations pohmelfs_file_ops = {
946 .open = generic_file_open,
947 .fsync = pohmelfs_fsync,
948
949 .llseek = generic_file_llseek,
950
951 .read = do_sync_read,
952 .aio_read = generic_file_aio_read,
953
954 .mmap = generic_file_mmap,
955
956 .splice_read = generic_file_splice_read,
957 .splice_write = generic_file_splice_write,
958
959 .write = pohmelfs_write,
960 .aio_write = generic_file_aio_write,
961 };
962
963 const struct inode_operations pohmelfs_symlink_inode_operations = {
964 .readlink = generic_readlink,
965 .follow_link = page_follow_link_light,
966 .put_link = page_put_link,
967 };
968
969 int pohmelfs_setattr_raw(struct inode *inode, struct iattr *attr)
970 {
971 int err;
972
973 err = inode_change_ok(inode, attr);
974 if (err) {
975 dprintk("%s: ino: %llu, inode changes are not allowed.\n", __func__, POHMELFS_I(inode)->ino);
976 goto err_out_exit;
977 }
978
979 if ((attr->ia_valid & ATTR_SIZE) &&
980 attr->ia_size != i_size_read(inode)) {
981 err = vmtruncate(inode, attr->ia_size);
982 if (err) {
983 dprintk("%s: ino: %llu, failed to set the attributes.\n", __func__, POHMELFS_I(inode)->ino);
984 goto err_out_exit;
985 }
986 }
987
988 setattr_copy(inode, attr);
989 mark_inode_dirty(inode);
990
991 dprintk("%s: ino: %llu, mode: %o -> %o, uid: %u -> %u, gid: %u -> %u, size: %llu -> %llu.\n",
992 __func__, POHMELFS_I(inode)->ino, inode->i_mode, attr->ia_mode,
993 inode->i_uid, attr->ia_uid, inode->i_gid, attr->ia_gid, inode->i_size, attr->ia_size);
994
995 return 0;
996
997 err_out_exit:
998 return err;
999 }
1000
1001 int pohmelfs_setattr(struct dentry *dentry, struct iattr *attr)
1002 {
1003 struct inode *inode = dentry->d_inode;
1004 struct pohmelfs_inode *pi = POHMELFS_I(inode);
1005 int err;
1006
1007 err = pohmelfs_data_lock(pi, 0, ~0, POHMELFS_WRITE_LOCK);
1008 if (err)
1009 goto err_out_exit;
1010
1011 err = security_inode_setattr(dentry, attr);
1012 if (err)
1013 goto err_out_exit;
1014
1015 err = pohmelfs_setattr_raw(inode, attr);
1016 if (err)
1017 goto err_out_exit;
1018
1019 return 0;
1020
1021 err_out_exit:
1022 return err;
1023 }
1024
1025 static int pohmelfs_send_xattr_req(struct pohmelfs_inode *pi, u64 id, u64 start,
1026 const char *name, const void *value, size_t attrsize, int command)
1027 {
1028 struct pohmelfs_sb *psb = POHMELFS_SB(pi->vfs_inode.i_sb);
1029 int err, path_len, namelen = strlen(name) + 1; /* 0-byte */
1030 struct netfs_trans *t;
1031 struct netfs_cmd *cmd;
1032 void *data;
1033
1034 dprintk("%s: id: %llu, start: %llu, name: '%s', attrsize: %zu, cmd: %d.\n",
1035 __func__, id, start, name, attrsize, command);
1036
1037 path_len = pohmelfs_path_length(pi);
1038 if (path_len < 0) {
1039 err = path_len;
1040 goto err_out_exit;
1041 }
1042
1043 t = netfs_trans_alloc(psb, namelen + path_len + attrsize, 0, 0);
1044 if (!t) {
1045 err = -ENOMEM;
1046 goto err_out_exit;
1047 }
1048
1049 cmd = netfs_trans_current(t);
1050 data = cmd + 1;
1051
1052 path_len = pohmelfs_construct_path_string(pi, data, path_len);
1053 if (path_len < 0) {
1054 err = path_len;
1055 goto err_out_put;
1056 }
1057 data += path_len;
1058
1059 /*
1060 * 'name' is a NUL-terminated string already and
1061 * 'namelen' includes 0-byte.
1062 */
1063 memcpy(data, name, namelen);
1064 data += namelen;
1065
1066 memcpy(data, value, attrsize);
1067
1068 cmd->cmd = command;
1069 cmd->id = id;
1070 cmd->start = start;
1071 cmd->size = attrsize + namelen + path_len;
1072 cmd->ext = path_len;
1073 cmd->csize = 0;
1074 cmd->cpad = 0;
1075
1076 netfs_convert_cmd(cmd);
1077 netfs_trans_update(cmd, t, namelen + path_len + attrsize);
1078
1079 return netfs_trans_finish(t, psb);
1080
1081 err_out_put:
1082 t->result = err;
1083 netfs_trans_put(t);
1084 err_out_exit:
1085 return err;
1086 }
1087
1088 static int pohmelfs_setxattr(struct dentry *dentry, const char *name,
1089 const void *value, size_t attrsize, int flags)
1090 {
1091 struct inode *inode = dentry->d_inode;
1092 struct pohmelfs_inode *pi = POHMELFS_I(inode);
1093 struct pohmelfs_sb *psb = POHMELFS_SB(inode->i_sb);
1094
1095 if (!(psb->state_flags & POHMELFS_FLAGS_XATTR))
1096 return -EOPNOTSUPP;
1097
1098 return pohmelfs_send_xattr_req(pi, flags, attrsize, name,
1099 value, attrsize, NETFS_XATTR_SET);
1100 }
1101
1102 static ssize_t pohmelfs_getxattr(struct dentry *dentry, const char *name,
1103 void *value, size_t attrsize)
1104 {
1105 struct inode *inode = dentry->d_inode;
1106 struct pohmelfs_inode *pi = POHMELFS_I(inode);
1107 struct pohmelfs_sb *psb = POHMELFS_SB(inode->i_sb);
1108 struct pohmelfs_mcache *m;
1109 int err;
1110 long timeout = psb->mcache_timeout;
1111
1112 if (!(psb->state_flags & POHMELFS_FLAGS_XATTR))
1113 return -EOPNOTSUPP;
1114
1115 m = pohmelfs_mcache_alloc(psb, 0, attrsize, value);
1116 if (IS_ERR(m))
1117 return PTR_ERR(m);
1118
1119 dprintk("%s: ino: %llu, name: '%s', size: %zu.\n",
1120 __func__, pi->ino, name, attrsize);
1121
1122 err = pohmelfs_send_xattr_req(pi, m->gen, attrsize, name, value, 0, NETFS_XATTR_GET);
1123 if (err)
1124 goto err_out_put;
1125
1126 do {
1127 err = wait_for_completion_timeout(&m->complete, timeout);
1128 if (err) {
1129 err = m->err;
1130 break;
1131 }
1132
1133 /*
1134 * This loop is a bit ugly, since it waits until reference counter
1135 * hits 1 and then puts the object here. Main goal is to prevent race with
1136 * the network thread, when it can start processing the given request, i.e.
1137 * increase its reference counter but yet not complete it, while
1138 * we will exit from ->getxattr() with timeout, and although request
1139 * will not be freed (its reference counter was increased by network
1140 * thread), data pointer provided by user may be released, so we will
1141 * overwrite an already freed area in the network thread.
1142 *
1143 * Now after timeout we remove request from the cache, so it can not be
1144 * found by network thread, and wait for its reference counter to hit 1,
1145 * i.e. if network thread already started to process this request, we wait
1146 * for it to finish, and then free object locally. If reference counter is
1147 * already 1, i.e. request is not used by anyone else, we can free it without
1148 * problem.
1149 */
1150 err = -ETIMEDOUT;
1151 timeout = HZ;
1152
1153 pohmelfs_mcache_remove_locked(psb, m);
1154 } while (atomic_read(&m->refcnt) != 1);
1155
1156 pohmelfs_mcache_put(psb, m);
1157
1158 dprintk("%s: ino: %llu, err: %d.\n", __func__, pi->ino, err);
1159
1160 return err;
1161
1162 err_out_put:
1163 pohmelfs_mcache_put(psb, m);
1164 return err;
1165 }
1166
1167 static int pohmelfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
1168 {
1169 struct inode *inode = dentry->d_inode;
1170 #if 0
1171 struct pohmelfs_inode *pi = POHMELFS_I(inode);
1172 int err;
1173
1174 err = pohmelfs_data_lock(pi, 0, ~0, POHMELFS_READ_LOCK);
1175 if (err)
1176 return err;
1177 dprintk("%s: ino: %llu, mode: %o, uid: %u, gid: %u, size: %llu.\n",
1178 __func__, pi->ino, inode->i_mode, inode->i_uid,
1179 inode->i_gid, inode->i_size);
1180 #endif
1181
1182 generic_fillattr(inode, stat);
1183 return 0;
1184 }
1185
1186 const struct inode_operations pohmelfs_file_inode_operations = {
1187 .setattr = pohmelfs_setattr,
1188 .getattr = pohmelfs_getattr,
1189 .setxattr = pohmelfs_setxattr,
1190 .getxattr = pohmelfs_getxattr,
1191 };
1192
1193 /*
1194 * Fill inode data: mode, size, operation callbacks and so on...
1195 */
1196 void pohmelfs_fill_inode(struct inode *inode, struct netfs_inode_info *info)
1197 {
1198 inode->i_mode = info->mode;
1199 set_nlink(inode, info->nlink);
1200 inode->i_uid = info->uid;
1201 inode->i_gid = info->gid;
1202 inode->i_blocks = info->blocks;
1203 inode->i_rdev = info->rdev;
1204 inode->i_size = info->size;
1205 inode->i_version = info->version;
1206 inode->i_blkbits = ffs(info->blocksize);
1207
1208 dprintk("%s: inode: %p, num: %lu/%llu inode is regular: %d, dir: %d, link: %d, mode: %o, size: %llu.\n",
1209 __func__, inode, inode->i_ino, info->ino,
1210 S_ISREG(inode->i_mode), S_ISDIR(inode->i_mode),
1211 S_ISLNK(inode->i_mode), inode->i_mode, inode->i_size);
1212
1213 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
1214
1215 /*
1216 * i_mapping is a pointer to i_data during inode initialization.
1217 */
1218 inode->i_data.a_ops = &pohmelfs_aops;
1219
1220 if (S_ISREG(inode->i_mode)) {
1221 inode->i_fop = &pohmelfs_file_ops;
1222 inode->i_op = &pohmelfs_file_inode_operations;
1223 } else if (S_ISDIR(inode->i_mode)) {
1224 inode->i_fop = &pohmelfs_dir_fops;
1225 inode->i_op = &pohmelfs_dir_inode_ops;
1226 } else if (S_ISLNK(inode->i_mode)) {
1227 inode->i_op = &pohmelfs_symlink_inode_operations;
1228 inode->i_fop = &pohmelfs_file_ops;
1229 } else {
1230 inode->i_fop = &generic_ro_fops;
1231 }
1232 }
1233
1234 static int pohmelfs_drop_inode(struct inode *inode)
1235 {
1236 struct pohmelfs_sb *psb = POHMELFS_SB(inode->i_sb);
1237 struct pohmelfs_inode *pi = POHMELFS_I(inode);
1238
1239 spin_lock(&psb->ino_lock);
1240 list_del_init(&pi->inode_entry);
1241 spin_unlock(&psb->ino_lock);
1242
1243 return generic_drop_inode(inode);
1244 }
1245
1246 static struct pohmelfs_inode *pohmelfs_get_inode_from_list(struct pohmelfs_sb *psb,
1247 struct list_head *head, unsigned int *count)
1248 {
1249 struct pohmelfs_inode *pi = NULL;
1250
1251 spin_lock(&psb->ino_lock);
1252 if (!list_empty(head)) {
1253 pi = list_entry(head->next, struct pohmelfs_inode,
1254 inode_entry);
1255 list_del_init(&pi->inode_entry);
1256 *count = pi->drop_count;
1257 pi->drop_count = 0;
1258 }
1259 spin_unlock(&psb->ino_lock);
1260
1261 return pi;
1262 }
1263
1264 static void pohmelfs_flush_transactions(struct pohmelfs_sb *psb)
1265 {
1266 struct pohmelfs_config *c;
1267
1268 mutex_lock(&psb->state_lock);
1269 list_for_each_entry(c, &psb->state_list, config_entry) {
1270 pohmelfs_state_flush_transactions(&c->state);
1271 }
1272 mutex_unlock(&psb->state_lock);
1273 }
1274
1275 /*
1276 * ->put_super() callback. Invoked before superblock is destroyed,
1277 * so it has to clean all private data.
1278 */
1279 static void pohmelfs_put_super(struct super_block *sb)
1280 {
1281 struct pohmelfs_sb *psb = POHMELFS_SB(sb);
1282 struct pohmelfs_inode *pi;
1283 unsigned int count = 0;
1284 unsigned int in_drop_list = 0;
1285 struct inode *inode, *tmp;
1286
1287 dprintk("%s.\n", __func__);
1288
1289 /*
1290 * Kill pending transactions, which could affect inodes in-flight.
1291 */
1292 pohmelfs_flush_transactions(psb);
1293
1294 while ((pi = pohmelfs_get_inode_from_list(psb, &psb->drop_list, &count))) {
1295 inode = &pi->vfs_inode;
1296
1297 dprintk("%s: ino: %llu, pi: %p, inode: %p, count: %u.\n",
1298 __func__, pi->ino, pi, inode, count);
1299
1300 if (atomic_read(&inode->i_count) != count) {
1301 printk("%s: ino: %llu, pi: %p, inode: %p, count: %u, i_count: %d.\n",
1302 __func__, pi->ino, pi, inode, count,
1303 atomic_read(&inode->i_count));
1304 count = atomic_read(&inode->i_count);
1305 in_drop_list++;
1306 }
1307
1308 while (count--)
1309 iput(&pi->vfs_inode);
1310 }
1311
1312 list_for_each_entry_safe(inode, tmp, &sb->s_inodes, i_sb_list) {
1313 pi = POHMELFS_I(inode);
1314
1315 dprintk("%s: ino: %llu, pi: %p, inode: %p, i_count: %u.\n",
1316 __func__, pi->ino, pi, inode, atomic_read(&inode->i_count));
1317
1318 /*
1319 * These are special inodes, they were created during
1320 * directory reading or lookup, and were not bound to dentry,
1321 * so they live here with reference counter being 1 and prevent
1322 * umount from succeed since it believes that they are busy.
1323 */
1324 count = atomic_read(&inode->i_count);
1325 if (count) {
1326 list_del_init(&inode->i_sb_list);
1327 while (count--)
1328 iput(&pi->vfs_inode);
1329 }
1330 }
1331
1332 psb->trans_scan_timeout = psb->drop_scan_timeout = 0;
1333 cancel_delayed_work_sync(&psb->dwork);
1334 cancel_delayed_work_sync(&psb->drop_dwork);
1335 flush_scheduled_work();
1336
1337 dprintk("%s: stopped workqueues.\n", __func__);
1338
1339 pohmelfs_crypto_exit(psb);
1340 pohmelfs_state_exit(psb);
1341
1342 bdi_destroy(&psb->bdi);
1343
1344 kfree(psb);
1345 sb->s_fs_info = NULL;
1346 }
1347
1348 static int pohmelfs_statfs(struct dentry *dentry, struct kstatfs *buf)
1349 {
1350 struct super_block *sb = dentry->d_sb;
1351 struct pohmelfs_sb *psb = POHMELFS_SB(sb);
1352
1353 /*
1354 * There are no filesystem size limits yet.
1355 */
1356 memset(buf, 0, sizeof(struct kstatfs));
1357
1358 buf->f_type = POHMELFS_MAGIC_NUM; /* 'POH.' */
1359 buf->f_bsize = sb->s_blocksize;
1360 buf->f_files = psb->ino;
1361 buf->f_namelen = 255;
1362 buf->f_files = atomic_long_read(&psb->total_inodes);
1363 buf->f_bfree = buf->f_bavail = psb->avail_size >> PAGE_SHIFT;
1364 buf->f_blocks = psb->total_size >> PAGE_SHIFT;
1365
1366 dprintk("%s: total: %llu, avail: %llu, inodes: %llu, bsize: %lu.\n",
1367 __func__, psb->total_size, psb->avail_size, buf->f_files, sb->s_blocksize);
1368
1369 return 0;
1370 }
1371
1372 static int pohmelfs_show_options(struct seq_file *seq, struct dentry *root)
1373 {
1374 struct pohmelfs_sb *psb = POHMELFS_SB(root->d_sb);
1375
1376 seq_printf(seq, ",idx=%u", psb->idx);
1377 seq_printf(seq, ",trans_scan_timeout=%u", jiffies_to_msecs(psb->trans_scan_timeout));
1378 seq_printf(seq, ",drop_scan_timeout=%u", jiffies_to_msecs(psb->drop_scan_timeout));
1379 seq_printf(seq, ",wait_on_page_timeout=%u", jiffies_to_msecs(psb->wait_on_page_timeout));
1380 seq_printf(seq, ",trans_retries=%u", psb->trans_retries);
1381 seq_printf(seq, ",crypto_thread_num=%u", psb->crypto_thread_num);
1382 seq_printf(seq, ",trans_max_pages=%u", psb->trans_max_pages);
1383 seq_printf(seq, ",mcache_timeout=%u", jiffies_to_msecs(psb->mcache_timeout));
1384 if (psb->crypto_fail_unsupported)
1385 seq_printf(seq, ",crypto_fail_unsupported");
1386
1387 return 0;
1388 }
1389
1390 enum {
1391 pohmelfs_opt_idx,
1392 pohmelfs_opt_crypto_thread_num,
1393 pohmelfs_opt_trans_max_pages,
1394 pohmelfs_opt_crypto_fail_unsupported,
1395
1396 /* Remountable options */
1397 pohmelfs_opt_trans_scan_timeout,
1398 pohmelfs_opt_drop_scan_timeout,
1399 pohmelfs_opt_wait_on_page_timeout,
1400 pohmelfs_opt_trans_retries,
1401 pohmelfs_opt_mcache_timeout,
1402 };
1403
1404 static struct match_token pohmelfs_tokens[] = {
1405 {pohmelfs_opt_idx, "idx=%u"},
1406 {pohmelfs_opt_crypto_thread_num, "crypto_thread_num=%u"},
1407 {pohmelfs_opt_trans_max_pages, "trans_max_pages=%u"},
1408 {pohmelfs_opt_crypto_fail_unsupported, "crypto_fail_unsupported"},
1409 {pohmelfs_opt_trans_scan_timeout, "trans_scan_timeout=%u"},
1410 {pohmelfs_opt_drop_scan_timeout, "drop_scan_timeout=%u"},
1411 {pohmelfs_opt_wait_on_page_timeout, "wait_on_page_timeout=%u"},
1412 {pohmelfs_opt_trans_retries, "trans_retries=%u"},
1413 {pohmelfs_opt_mcache_timeout, "mcache_timeout=%u"},
1414 };
1415
1416 static int pohmelfs_parse_options(char *options, struct pohmelfs_sb *psb, int remount)
1417 {
1418 char *p;
1419 substring_t args[MAX_OPT_ARGS];
1420 int option, err;
1421
1422 if (!options)
1423 return 0;
1424
1425 while ((p = strsep(&options, ",")) != NULL) {
1426 int token;
1427 if (!*p)
1428 continue;
1429
1430 token = match_token(p, pohmelfs_tokens, args);
1431
1432 err = match_int(&args[0], &option);
1433 if (err)
1434 return err;
1435
1436 if (remount && token <= pohmelfs_opt_crypto_fail_unsupported)
1437 continue;
1438
1439 switch (token) {
1440 case pohmelfs_opt_idx:
1441 psb->idx = option;
1442 break;
1443 case pohmelfs_opt_trans_scan_timeout:
1444 psb->trans_scan_timeout = msecs_to_jiffies(option);
1445 break;
1446 case pohmelfs_opt_drop_scan_timeout:
1447 psb->drop_scan_timeout = msecs_to_jiffies(option);
1448 break;
1449 case pohmelfs_opt_wait_on_page_timeout:
1450 psb->wait_on_page_timeout = msecs_to_jiffies(option);
1451 break;
1452 case pohmelfs_opt_mcache_timeout:
1453 psb->mcache_timeout = msecs_to_jiffies(option);
1454 break;
1455 case pohmelfs_opt_trans_retries:
1456 psb->trans_retries = option;
1457 break;
1458 case pohmelfs_opt_crypto_thread_num:
1459 psb->crypto_thread_num = option;
1460 break;
1461 case pohmelfs_opt_trans_max_pages:
1462 psb->trans_max_pages = option;
1463 break;
1464 case pohmelfs_opt_crypto_fail_unsupported:
1465 psb->crypto_fail_unsupported = 1;
1466 break;
1467 default:
1468 return -EINVAL;
1469 }
1470 }
1471
1472 return 0;
1473 }
1474
1475 static int pohmelfs_remount(struct super_block *sb, int *flags, char *data)
1476 {
1477 int err;
1478 struct pohmelfs_sb *psb = POHMELFS_SB(sb);
1479 unsigned long old_sb_flags = sb->s_flags;
1480
1481 err = pohmelfs_parse_options(data, psb, 1);
1482 if (err)
1483 goto err_out_restore;
1484
1485 if (!(*flags & MS_RDONLY))
1486 sb->s_flags &= ~MS_RDONLY;
1487 return 0;
1488
1489 err_out_restore:
1490 sb->s_flags = old_sb_flags;
1491 return err;
1492 }
1493
1494 static void pohmelfs_flush_inode(struct pohmelfs_inode *pi, unsigned int count)
1495 {
1496 struct inode *inode = &pi->vfs_inode;
1497
1498 dprintk("%s: %p: ino: %llu, owned: %d.\n",
1499 __func__, inode, pi->ino, test_bit(NETFS_INODE_OWNED, &pi->state));
1500
1501 mutex_lock(&inode->i_mutex);
1502 if (test_and_clear_bit(NETFS_INODE_OWNED, &pi->state)) {
1503 filemap_fdatawrite(inode->i_mapping);
1504 inode->i_sb->s_op->write_inode(inode, 0);
1505 }
1506
1507 #ifdef POHMELFS_TRUNCATE_ON_INODE_FLUSH
1508 truncate_inode_pages(inode->i_mapping, 0);
1509 #endif
1510
1511 pohmelfs_data_unlock(pi, 0, ~0, POHMELFS_WRITE_LOCK);
1512 mutex_unlock(&inode->i_mutex);
1513 }
1514
1515 static void pohmelfs_put_inode_count(struct pohmelfs_inode *pi, unsigned int count)
1516 {
1517 dprintk("%s: ino: %llu, pi: %p, inode: %p, count: %u.\n",
1518 __func__, pi->ino, pi, &pi->vfs_inode, count);
1519
1520 if (test_and_clear_bit(NETFS_INODE_NEED_FLUSH, &pi->state))
1521 pohmelfs_flush_inode(pi, count);
1522
1523 while (count--)
1524 iput(&pi->vfs_inode);
1525 }
1526
1527 static void pohmelfs_drop_scan(struct work_struct *work)
1528 {
1529 struct pohmelfs_sb *psb =
1530 container_of(work, struct pohmelfs_sb, drop_dwork.work);
1531 struct pohmelfs_inode *pi;
1532 unsigned int count = 0;
1533
1534 while ((pi = pohmelfs_get_inode_from_list(psb, &psb->drop_list, &count)))
1535 pohmelfs_put_inode_count(pi, count);
1536
1537 pohmelfs_check_states(psb);
1538
1539 if (psb->drop_scan_timeout)
1540 schedule_delayed_work(&psb->drop_dwork, psb->drop_scan_timeout);
1541 }
1542
1543 /*
1544 * Run through all transactions starting from the oldest,
1545 * drop transaction from current state and try to send it
1546 * to all remote nodes, which are currently installed.
1547 */
1548 static void pohmelfs_trans_scan_state(struct netfs_state *st)
1549 {
1550 struct rb_node *rb_node;
1551 struct netfs_trans_dst *dst;
1552 struct pohmelfs_sb *psb = st->psb;
1553 unsigned int timeout = psb->trans_scan_timeout;
1554 struct netfs_trans *t;
1555 int err;
1556
1557 mutex_lock(&st->trans_lock);
1558 for (rb_node = rb_first(&st->trans_root); rb_node; ) {
1559 dst = rb_entry(rb_node, struct netfs_trans_dst, state_entry);
1560 t = dst->trans;
1561
1562 if (timeout && time_after(dst->send_time + timeout, jiffies)
1563 && dst->retries == 0)
1564 break;
1565
1566 dprintk("%s: t: %p, gen: %u, st: %p, retries: %u, max: %u.\n",
1567 __func__, t, t->gen, st, dst->retries, psb->trans_retries);
1568 netfs_trans_get(t);
1569
1570 rb_node = rb_next(rb_node);
1571
1572 err = -ETIMEDOUT;
1573 if (timeout && (++dst->retries < psb->trans_retries))
1574 err = netfs_trans_resend(t, psb);
1575
1576 if (err || (t->flags & NETFS_TRANS_SINGLE_DST)) {
1577 if (netfs_trans_remove_nolock(dst, st))
1578 netfs_trans_drop_dst_nostate(dst);
1579 }
1580
1581 t->result = err;
1582 netfs_trans_put(t);
1583 }
1584 mutex_unlock(&st->trans_lock);
1585 }
1586
1587 /*
1588 * Walk through all installed network states and resend all
1589 * transactions, which are old enough.
1590 */
1591 static void pohmelfs_trans_scan(struct work_struct *work)
1592 {
1593 struct pohmelfs_sb *psb =
1594 container_of(work, struct pohmelfs_sb, dwork.work);
1595 struct netfs_state *st;
1596 struct pohmelfs_config *c;
1597
1598 mutex_lock(&psb->state_lock);
1599 list_for_each_entry(c, &psb->state_list, config_entry) {
1600 st = &c->state;
1601
1602 pohmelfs_trans_scan_state(st);
1603 }
1604 mutex_unlock(&psb->state_lock);
1605
1606 /*
1607 * If no timeout specified then system is in the middle of umount process,
1608 * so no need to reschedule scanning process again.
1609 */
1610 if (psb->trans_scan_timeout)
1611 schedule_delayed_work(&psb->dwork, psb->trans_scan_timeout);
1612 }
1613
1614 int pohmelfs_meta_command_data(struct pohmelfs_inode *pi, u64 id, unsigned int cmd_op, char *addon,
1615 unsigned int flags, netfs_trans_complete_t complete, void *priv, u64 start)
1616 {
1617 struct inode *inode = &pi->vfs_inode;
1618 struct pohmelfs_sb *psb = POHMELFS_SB(inode->i_sb);
1619 int err = 0, sz;
1620 struct netfs_trans *t;
1621 int path_len, addon_len = 0;
1622 void *data;
1623 struct netfs_inode_info *info;
1624 struct netfs_cmd *cmd;
1625
1626 dprintk("%s: ino: %llu, cmd: %u, addon: %p.\n", __func__, pi->ino, cmd_op, addon);
1627
1628 path_len = pohmelfs_path_length(pi);
1629 if (path_len < 0) {
1630 err = path_len;
1631 goto err_out_exit;
1632 }
1633
1634 if (addon)
1635 addon_len = strlen(addon) + 1; /* 0-byte */
1636 sz = addon_len;
1637
1638 if (cmd_op == NETFS_INODE_INFO)
1639 sz += sizeof(struct netfs_inode_info);
1640
1641 t = netfs_trans_alloc(psb, sz + path_len, flags, 0);
1642 if (!t) {
1643 err = -ENOMEM;
1644 goto err_out_exit;
1645 }
1646 t->complete = complete;
1647 t->private = priv;
1648
1649 cmd = netfs_trans_current(t);
1650 data = (void *)(cmd + 1);
1651
1652 if (cmd_op == NETFS_INODE_INFO) {
1653 info = (struct netfs_inode_info *)(cmd + 1);
1654 data = (void *)(info + 1);
1655
1656 /*
1657 * We are under i_mutex, can read and change whatever we want...
1658 */
1659 info->mode = inode->i_mode;
1660 info->nlink = inode->i_nlink;
1661 info->uid = inode->i_uid;
1662 info->gid = inode->i_gid;
1663 info->blocks = inode->i_blocks;
1664 info->rdev = inode->i_rdev;
1665 info->size = inode->i_size;
1666 info->version = inode->i_version;
1667
1668 netfs_convert_inode_info(info);
1669 }
1670
1671 path_len = pohmelfs_construct_path_string(pi, data, path_len);
1672 if (path_len < 0)
1673 goto err_out_free;
1674
1675 dprintk("%s: path_len: %d.\n", __func__, path_len);
1676
1677 if (addon) {
1678 path_len--; /* Do not place null-byte before the addon */
1679 path_len += sprintf(data + path_len, "/%s", addon) + 1; /* 0 - byte */
1680 }
1681
1682 sz += path_len;
1683
1684 cmd->cmd = cmd_op;
1685 cmd->ext = path_len;
1686 cmd->size = sz;
1687 cmd->id = id;
1688 cmd->start = start;
1689
1690 netfs_convert_cmd(cmd);
1691 netfs_trans_update(cmd, t, sz);
1692
1693 /*
1694 * Note, that it is possible to leak error here: transaction callback will not
1695 * be invoked for allocation path failure.
1696 */
1697 return netfs_trans_finish(t, psb);
1698
1699 err_out_free:
1700 netfs_trans_free(t);
1701 err_out_exit:
1702 if (complete)
1703 complete(NULL, 0, priv, err);
1704 return err;
1705 }
1706
1707 int pohmelfs_meta_command(struct pohmelfs_inode *pi, unsigned int cmd_op, unsigned int flags,
1708 netfs_trans_complete_t complete, void *priv, u64 start)
1709 {
1710 return pohmelfs_meta_command_data(pi, pi->ino, cmd_op, NULL, flags, complete, priv, start);
1711 }
1712
1713 /*
1714 * Send request and wait for POHMELFS root capabilities response,
1715 * which will update server's informaion about size of the export,
1716 * permissions, number of objects, available size and so on.
1717 */
1718 static int pohmelfs_root_handshake(struct pohmelfs_sb *psb)
1719 {
1720 struct netfs_trans *t;
1721 struct netfs_cmd *cmd;
1722 int err = -ENOMEM;
1723
1724 t = netfs_trans_alloc(psb, 0, 0, 0);
1725 if (!t)
1726 goto err_out_exit;
1727
1728 cmd = netfs_trans_current(t);
1729
1730 cmd->cmd = NETFS_CAPABILITIES;
1731 cmd->id = POHMELFS_ROOT_CAPABILITIES;
1732 cmd->size = 0;
1733 cmd->start = 0;
1734 cmd->ext = 0;
1735 cmd->csize = 0;
1736
1737 netfs_convert_cmd(cmd);
1738 netfs_trans_update(cmd, t, 0);
1739
1740 err = netfs_trans_finish(t, psb);
1741 if (err)
1742 goto err_out_exit;
1743
1744 psb->flags = ~0;
1745 err = wait_event_interruptible_timeout(psb->wait,
1746 (psb->flags != ~0),
1747 psb->wait_on_page_timeout);
1748 if (!err)
1749 err = -ETIMEDOUT;
1750 else if (err > 0)
1751 err = -psb->flags;
1752
1753 if (err)
1754 goto err_out_exit;
1755
1756 return 0;
1757
1758 err_out_exit:
1759 return err;
1760 }
1761
1762 static int pohmelfs_show_stats(struct seq_file *m, struct dentry *root)
1763 {
1764 struct netfs_state *st;
1765 struct pohmelfs_ctl *ctl;
1766 struct pohmelfs_sb *psb = POHMELFS_SB(root->d_sb);
1767 struct pohmelfs_config *c;
1768
1769 mutex_lock(&psb->state_lock);
1770
1771 seq_printf(m, "\nidx addr(:port) socket_type protocol active priority permissions\n");
1772
1773 list_for_each_entry(c, &psb->state_list, config_entry) {
1774 st = &c->state;
1775 ctl = &st->ctl;
1776
1777 seq_printf(m, "%u ", ctl->idx);
1778 if (ctl->addr.sa_family == AF_INET) {
1779 struct sockaddr_in *sin = (struct sockaddr_in *)&st->ctl.addr;
1780 seq_printf(m, "%pI4:%u", &sin->sin_addr.s_addr, ntohs(sin->sin_port));
1781 } else if (ctl->addr.sa_family == AF_INET6) {
1782 struct sockaddr_in6 *sin = (struct sockaddr_in6 *)&st->ctl.addr;
1783 seq_printf(m, "%pi6:%u", &sin->sin6_addr, ntohs(sin->sin6_port));
1784 } else {
1785 unsigned int i;
1786 for (i = 0; i < ctl->addrlen; ++i)
1787 seq_printf(m, "%02x.", ctl->addr.addr[i]);
1788 }
1789
1790 seq_printf(m, " %u %u %d %u %x\n",
1791 ctl->type, ctl->proto,
1792 st->socket != NULL,
1793 ctl->prio, ctl->perm);
1794 }
1795 mutex_unlock(&psb->state_lock);
1796
1797 return 0;
1798 }
1799
1800 static const struct super_operations pohmelfs_sb_ops = {
1801 .alloc_inode = pohmelfs_alloc_inode,
1802 .destroy_inode = pohmelfs_destroy_inode,
1803 .drop_inode = pohmelfs_drop_inode,
1804 .write_inode = pohmelfs_write_inode,
1805 .put_super = pohmelfs_put_super,
1806 .remount_fs = pohmelfs_remount,
1807 .statfs = pohmelfs_statfs,
1808 .show_options = pohmelfs_show_options,
1809 .show_stats = pohmelfs_show_stats,
1810 };
1811
1812 /*
1813 * Allocate private superblock and create root dir.
1814 */
1815 static int pohmelfs_fill_super(struct super_block *sb, void *data, int silent)
1816 {
1817 struct pohmelfs_sb *psb;
1818 int err = -ENOMEM;
1819 struct inode *root;
1820 struct pohmelfs_inode *npi;
1821 struct qstr str;
1822
1823 psb = kzalloc(sizeof(struct pohmelfs_sb), GFP_KERNEL);
1824 if (!psb)
1825 goto err_out_exit;
1826
1827 err = bdi_init(&psb->bdi);
1828 if (err)
1829 goto err_out_free_sb;
1830
1831 err = bdi_register(&psb->bdi, NULL, "pfs-%d", atomic_inc_return(&psb_bdi_num));
1832 if (err) {
1833 bdi_destroy(&psb->bdi);
1834 goto err_out_free_sb;
1835 }
1836
1837 sb->s_fs_info = psb;
1838 sb->s_op = &pohmelfs_sb_ops;
1839 sb->s_magic = POHMELFS_MAGIC_NUM;
1840 sb->s_maxbytes = MAX_LFS_FILESIZE;
1841 sb->s_blocksize = PAGE_SIZE;
1842 sb->s_bdi = &psb->bdi;
1843
1844 psb->sb = sb;
1845
1846 psb->ino = 2;
1847 psb->idx = 0;
1848 psb->active_state = NULL;
1849 psb->trans_retries = 5;
1850 psb->trans_data_size = PAGE_SIZE;
1851 psb->drop_scan_timeout = msecs_to_jiffies(1000);
1852 psb->trans_scan_timeout = msecs_to_jiffies(5000);
1853 psb->wait_on_page_timeout = msecs_to_jiffies(5000);
1854 init_waitqueue_head(&psb->wait);
1855
1856 spin_lock_init(&psb->ino_lock);
1857
1858 INIT_LIST_HEAD(&psb->drop_list);
1859
1860 mutex_init(&psb->mcache_lock);
1861 psb->mcache_root = RB_ROOT;
1862 psb->mcache_timeout = msecs_to_jiffies(5000);
1863 atomic_long_set(&psb->mcache_gen, 0);
1864
1865 psb->trans_max_pages = 100;
1866
1867 psb->crypto_align_size = 16;
1868 psb->crypto_attached_size = 0;
1869 psb->hash_strlen = 0;
1870 psb->cipher_strlen = 0;
1871 psb->perform_crypto = 0;
1872 psb->crypto_thread_num = 2;
1873 psb->crypto_fail_unsupported = 0;
1874 mutex_init(&psb->crypto_thread_lock);
1875 INIT_LIST_HEAD(&psb->crypto_ready_list);
1876 INIT_LIST_HEAD(&psb->crypto_active_list);
1877
1878 atomic_set(&psb->trans_gen, 1);
1879 atomic_long_set(&psb->total_inodes, 0);
1880
1881 mutex_init(&psb->state_lock);
1882 INIT_LIST_HEAD(&psb->state_list);
1883
1884 err = pohmelfs_parse_options((char *) data, psb, 0);
1885 if (err)
1886 goto err_out_free_bdi;
1887
1888 err = pohmelfs_copy_crypto(psb);
1889 if (err)
1890 goto err_out_free_bdi;
1891
1892 err = pohmelfs_state_init(psb);
1893 if (err)
1894 goto err_out_free_strings;
1895
1896 err = pohmelfs_crypto_init(psb);
1897 if (err)
1898 goto err_out_state_exit;
1899
1900 err = pohmelfs_root_handshake(psb);
1901 if (err)
1902 goto err_out_crypto_exit;
1903
1904 str.name = "/";
1905 str.hash = jhash("/", 1, 0);
1906 str.len = 1;
1907
1908 npi = pohmelfs_create_entry_local(psb, NULL, &str, 0, 0755|S_IFDIR);
1909 if (IS_ERR(npi)) {
1910 err = PTR_ERR(npi);
1911 goto err_out_crypto_exit;
1912 }
1913 set_bit(NETFS_INODE_REMOTE_SYNCED, &npi->state);
1914 clear_bit(NETFS_INODE_OWNED, &npi->state);
1915
1916 root = &npi->vfs_inode;
1917
1918 sb->s_root = d_alloc_root(root);
1919 if (!sb->s_root)
1920 goto err_out_put_root;
1921
1922 INIT_DELAYED_WORK(&psb->drop_dwork, pohmelfs_drop_scan);
1923 schedule_delayed_work(&psb->drop_dwork, psb->drop_scan_timeout);
1924
1925 INIT_DELAYED_WORK(&psb->dwork, pohmelfs_trans_scan);
1926 schedule_delayed_work(&psb->dwork, psb->trans_scan_timeout);
1927
1928 return 0;
1929
1930 err_out_put_root:
1931 iput(root);
1932 err_out_crypto_exit:
1933 pohmelfs_crypto_exit(psb);
1934 err_out_state_exit:
1935 pohmelfs_state_exit(psb);
1936 err_out_free_strings:
1937 kfree(psb->cipher_string);
1938 kfree(psb->hash_string);
1939 err_out_free_bdi:
1940 bdi_destroy(&psb->bdi);
1941 err_out_free_sb:
1942 kfree(psb);
1943 err_out_exit:
1944
1945 dprintk("%s: err: %d.\n", __func__, err);
1946 return err;
1947 }
1948
1949 /*
1950 * Some VFS magic here...
1951 */
1952 static struct dentry *pohmelfs_mount(struct file_system_type *fs_type,
1953 int flags, const char *dev_name, void *data)
1954 {
1955 return mount_nodev(fs_type, flags, data, pohmelfs_fill_super);
1956 }
1957
1958 /*
1959 * We need this to sync all inodes earlier, since when writeback
1960 * is invoked from the umount/mntput path dcache is already shrunk,
1961 * see generic_shutdown_super(), and no inodes can access the path.
1962 */
1963 static void pohmelfs_kill_super(struct super_block *sb)
1964 {
1965 sync_inodes_sb(sb);
1966 kill_anon_super(sb);
1967 }
1968
1969 static struct file_system_type pohmel_fs_type = {
1970 .owner = THIS_MODULE,
1971 .name = "pohmel",
1972 .mount = pohmelfs_mount,
1973 .kill_sb = pohmelfs_kill_super,
1974 };
1975
1976 /*
1977 * Cache and module initializations and freeing routings.
1978 */
1979 static void pohmelfs_init_once(void *data)
1980 {
1981 struct pohmelfs_inode *pi = data;
1982
1983 inode_init_once(&pi->vfs_inode);
1984 }
1985
1986 static int __init pohmelfs_init_inodecache(void)
1987 {
1988 pohmelfs_inode_cache = kmem_cache_create("pohmelfs_inode_cache",
1989 sizeof(struct pohmelfs_inode),
1990 0, (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD),
1991 pohmelfs_init_once);
1992 if (!pohmelfs_inode_cache)
1993 return -ENOMEM;
1994
1995 return 0;
1996 }
1997
1998 static void pohmelfs_destroy_inodecache(void)
1999 {
2000 kmem_cache_destroy(pohmelfs_inode_cache);
2001 }
2002
2003 static int __init init_pohmel_fs(void)
2004 {
2005 int err;
2006
2007 err = pohmelfs_config_init();
2008 if (err)
2009 goto err_out_exit;
2010
2011 err = pohmelfs_init_inodecache();
2012 if (err)
2013 goto err_out_config_exit;
2014
2015 err = pohmelfs_mcache_init();
2016 if (err)
2017 goto err_out_destroy;
2018
2019 err = netfs_trans_init();
2020 if (err)
2021 goto err_out_mcache_exit;
2022
2023 err = register_filesystem(&pohmel_fs_type);
2024 if (err)
2025 goto err_out_trans;
2026
2027 return 0;
2028
2029 err_out_trans:
2030 netfs_trans_exit();
2031 err_out_mcache_exit:
2032 pohmelfs_mcache_exit();
2033 err_out_destroy:
2034 pohmelfs_destroy_inodecache();
2035 err_out_config_exit:
2036 pohmelfs_config_exit();
2037 err_out_exit:
2038 return err;
2039 }
2040
2041 static void __exit exit_pohmel_fs(void)
2042 {
2043 unregister_filesystem(&pohmel_fs_type);
2044 pohmelfs_destroy_inodecache();
2045 pohmelfs_mcache_exit();
2046 pohmelfs_config_exit();
2047 netfs_trans_exit();
2048 }
2049
2050 module_init(init_pohmel_fs);
2051 module_exit(exit_pohmel_fs);
2052
2053 MODULE_LICENSE("GPL");
2054 MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>");
2055 MODULE_DESCRIPTION("Pohmel filesystem");
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