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GUI: Fix Tomato RAF theme for all builds. Compilation typo.
[tomato.git] / release / src-rt-6.x.4708 / linux / linux-2.6.36 / fs / exofs / inode.c
blobeccadb3b552b8c7bc263429086ee9c531c6213e0
1 /*
2 * Copyright (C) 2005, 2006
3 * Avishay Traeger (avishay@gmail.com)
4 * Copyright (C) 2008, 2009
5 * Boaz Harrosh <bharrosh@panasas.com>
6 *
7 * Copyrights for code taken from ext2:
8 * Copyright (C) 1992, 1993, 1994, 1995
9 * Remy Card (card@masi.ibp.fr)
10 * Laboratoire MASI - Institut Blaise Pascal
11 * Universite Pierre et Marie Curie (Paris VI)
12 * from
13 * linux/fs/minix/inode.c
14 * Copyright (C) 1991, 1992 Linus Torvalds
15 *
16 * This file is part of exofs.
17 *
18 * exofs is free software; you can redistribute it and/or modify
19 * it under the terms of the GNU General Public License as published by
20 * the Free Software Foundation. Since it is based on ext2, and the only
21 * valid version of GPL for the Linux kernel is version 2, the only valid
22 * version of GPL for exofs is version 2.
23 *
24 * exofs is distributed in the hope that it will be useful,
25 * but WITHOUT ANY WARRANTY; without even the implied warranty of
26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
27 * GNU General Public License for more details.
28 *
29 * You should have received a copy of the GNU General Public License
30 * along with exofs; if not, write to the Free Software
31 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
32 */
33
34 #include <linux/slab.h>
35
36 #include "exofs.h"
37
38 #define EXOFS_DBGMSG2(M...) do {} while (0)
39
40 enum { BIO_MAX_PAGES_KMALLOC =
41 (PAGE_SIZE - sizeof(struct bio)) / sizeof(struct bio_vec),
42 MAX_PAGES_KMALLOC =
43 PAGE_SIZE / sizeof(struct page *),
44 };
45
46 struct page_collect {
47 struct exofs_sb_info *sbi;
48 struct inode *inode;
49 unsigned expected_pages;
50 struct exofs_io_state *ios;
51
52 struct page **pages;
53 unsigned alloc_pages;
54 unsigned nr_pages;
55 unsigned long length;
56 loff_t pg_first; /* keep 64bit also in 32-arches */
57 bool read_4_write; /* This means two things: that the read is sync
58 * And the pages should not be unlocked.
59 */
60 };
61
62 static void _pcol_init(struct page_collect *pcol, unsigned expected_pages,
63 struct inode *inode)
64 {
65 struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
66
67 pcol->sbi = sbi;
68 pcol->inode = inode;
69 pcol->expected_pages = expected_pages;
70
71 pcol->ios = NULL;
72 pcol->pages = NULL;
73 pcol->alloc_pages = 0;
74 pcol->nr_pages = 0;
75 pcol->length = 0;
76 pcol->pg_first = -1;
77 pcol->read_4_write = false;
78 }
79
80 static void _pcol_reset(struct page_collect *pcol)
81 {
82 pcol->expected_pages -= min(pcol->nr_pages, pcol->expected_pages);
83
84 pcol->pages = NULL;
85 pcol->alloc_pages = 0;
86 pcol->nr_pages = 0;
87 pcol->length = 0;
88 pcol->pg_first = -1;
89 pcol->ios = NULL;
90
91 /* this is probably the end of the loop but in writes
92 * it might not end here. don't be left with nothing
93 */
94 if (!pcol->expected_pages)
95 pcol->expected_pages = MAX_PAGES_KMALLOC;
96 }
97
98 static int pcol_try_alloc(struct page_collect *pcol)
99 {
100 unsigned pages = min_t(unsigned, pcol->expected_pages,
101 MAX_PAGES_KMALLOC);
102
103 if (!pcol->ios) { /* First time allocate io_state */
104 int ret = exofs_get_io_state(&pcol->sbi->layout, &pcol->ios);
105
106 if (ret)
107 return ret;
108 }
109
110 /* TODO: easily support bio chaining */
111 pages = min_t(unsigned, pages,
112 pcol->sbi->layout.group_width * BIO_MAX_PAGES_KMALLOC);
113
114 for (; pages; pages >>= 1) {
115 pcol->pages = kmalloc(pages * sizeof(struct page *),
116 GFP_KERNEL);
117 if (likely(pcol->pages)) {
118 pcol->alloc_pages = pages;
119 return 0;
120 }
121 }
122
123 EXOFS_ERR("Failed to kmalloc expected_pages=%u\n",
124 pcol->expected_pages);
125 return -ENOMEM;
126 }
127
128 static void pcol_free(struct page_collect *pcol)
129 {
130 kfree(pcol->pages);
131 pcol->pages = NULL;
132
133 if (pcol->ios) {
134 exofs_put_io_state(pcol->ios);
135 pcol->ios = NULL;
136 }
137 }
138
139 static int pcol_add_page(struct page_collect *pcol, struct page *page,
140 unsigned len)
141 {
142 if (unlikely(pcol->nr_pages >= pcol->alloc_pages))
143 return -ENOMEM;
144
145 pcol->pages[pcol->nr_pages++] = page;
146 pcol->length += len;
147 return 0;
148 }
149
150 static int update_read_page(struct page *page, int ret)
151 {
152 if (ret == 0) {
153 /* Everything is OK */
154 SetPageUptodate(page);
155 if (PageError(page))
156 ClearPageError(page);
157 } else if (ret == -EFAULT) {
158 /* In this case we were trying to read something that wasn't on
159 * disk yet - return a page full of zeroes. This should be OK,
160 * because the object should be empty (if there was a write
161 * before this read, the read would be waiting with the page
162 * locked */
163 clear_highpage(page);
164
165 SetPageUptodate(page);
166 if (PageError(page))
167 ClearPageError(page);
168 ret = 0; /* recovered error */
169 EXOFS_DBGMSG("recovered read error\n");
170 } else /* Error */
171 SetPageError(page);
172
173 return ret;
174 }
175
176 static void update_write_page(struct page *page, int ret)
177 {
178 if (ret) {
179 mapping_set_error(page->mapping, ret);
180 SetPageError(page);
181 }
182 end_page_writeback(page);
183 }
184
185 /* Called at the end of reads, to optionally unlock pages and update their
186 * status.
187 */
188 static int __readpages_done(struct page_collect *pcol, bool do_unlock)
189 {
190 int i;
191 u64 resid;
192 u64 good_bytes;
193 u64 length = 0;
194 int ret = exofs_check_io(pcol->ios, &resid);
195
196 if (likely(!ret))
197 good_bytes = pcol->length;
198 else
199 good_bytes = pcol->length - resid;
200
201 EXOFS_DBGMSG2("readpages_done(0x%lx) good_bytes=0x%llx"
202 " length=0x%lx nr_pages=%u\n",
203 pcol->inode->i_ino, _LLU(good_bytes), pcol->length,
204 pcol->nr_pages);
205
206 for (i = 0; i < pcol->nr_pages; i++) {
207 struct page *page = pcol->pages[i];
208 struct inode *inode = page->mapping->host;
209 int page_stat;
210
211 if (inode != pcol->inode)
212 continue; /* osd might add more pages at end */
213
214 if (likely(length < good_bytes))
215 page_stat = 0;
216 else
217 page_stat = ret;
218
219 EXOFS_DBGMSG2(" readpages_done(0x%lx, 0x%lx) %s\n",
220 inode->i_ino, page->index,
221 page_stat ? "bad_bytes" : "good_bytes");
222
223 ret = update_read_page(page, page_stat);
224 if (do_unlock)
225 unlock_page(page);
226 length += PAGE_SIZE;
227 }
228
229 pcol_free(pcol);
230 EXOFS_DBGMSG2("readpages_done END\n");
231 return ret;
232 }
233
234 /* callback of async reads */
235 static void readpages_done(struct exofs_io_state *ios, void *p)
236 {
237 struct page_collect *pcol = p;
238
239 __readpages_done(pcol, true);
240 atomic_dec(&pcol->sbi->s_curr_pending);
241 kfree(pcol);
242 }
243
244 static void _unlock_pcol_pages(struct page_collect *pcol, int ret, int rw)
245 {
246 int i;
247
248 for (i = 0; i < pcol->nr_pages; i++) {
249 struct page *page = pcol->pages[i];
250
251 if (rw == READ)
252 update_read_page(page, ret);
253 else
254 update_write_page(page, ret);
255
256 unlock_page(page);
257 }
258 }
259
260 static int read_exec(struct page_collect *pcol, bool is_sync)
261 {
262 struct exofs_i_info *oi = exofs_i(pcol->inode);
263 struct exofs_io_state *ios = pcol->ios;
264 struct page_collect *pcol_copy = NULL;
265 int ret;
266
267 if (!pcol->pages)
268 return 0;
269
270 /* see comment in _readpage() about sync reads */
271 WARN_ON(is_sync && (pcol->nr_pages != 1));
272
273 ios->pages = pcol->pages;
274 ios->nr_pages = pcol->nr_pages;
275 ios->length = pcol->length;
276 ios->offset = pcol->pg_first << PAGE_CACHE_SHIFT;
277
278 if (is_sync) {
279 exofs_oi_read(oi, pcol->ios);
280 return __readpages_done(pcol, false);
281 }
282
283 pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL);
284 if (!pcol_copy) {
285 ret = -ENOMEM;
286 goto err;
287 }
288
289 *pcol_copy = *pcol;
290 ios->done = readpages_done;
291 ios->private = pcol_copy;
292 ret = exofs_oi_read(oi, ios);
293 if (unlikely(ret))
294 goto err;
295
296 atomic_inc(&pcol->sbi->s_curr_pending);
297
298 EXOFS_DBGMSG2("read_exec obj=0x%llx start=0x%llx length=0x%lx\n",
299 ios->obj.id, _LLU(ios->offset), pcol->length);
300
301 /* pages ownership was passed to pcol_copy */
302 _pcol_reset(pcol);
303 return 0;
304
305 err:
306 if (!is_sync)
307 _unlock_pcol_pages(pcol, ret, READ);
308
309 pcol_free(pcol);
310
311 kfree(pcol_copy);
312 return ret;
313 }
314
315 /* readpage_strip is called either directly from readpage() or by the VFS from
316 * within read_cache_pages(), to add one more page to be read. It will try to
317 * collect as many contiguous pages as posible. If a discontinuity is
318 * encountered, or it runs out of resources, it will submit the previous segment
319 * and will start a new collection. Eventually caller must submit the last
320 * segment if present.
321 */
322 static int readpage_strip(void *data, struct page *page)
323 {
324 struct page_collect *pcol = data;
325 struct inode *inode = pcol->inode;
326 struct exofs_i_info *oi = exofs_i(inode);
327 loff_t i_size = i_size_read(inode);
328 pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
329 size_t len;
330 int ret;
331
332 if (PageUptodate(page))
333 EXOFS_ERR("PageUptodate(0x%lx, 0x%lx)\n", pcol->inode->i_ino,
334 page->index);
335
336 if (page->index < end_index)
337 len = PAGE_CACHE_SIZE;
338 else if (page->index == end_index)
339 len = i_size & ~PAGE_CACHE_MASK;
340 else
341 len = 0;
342
343 if (!len || !obj_created(oi)) {
344 /* this will be out of bounds, or doesn't exist yet.
345 * Current page is cleared and the request is split
346 */
347 clear_highpage(page);
348
349 SetPageUptodate(page);
350 if (PageError(page))
351 ClearPageError(page);
352
353 if (!pcol->read_4_write)
354 unlock_page(page);
355 EXOFS_DBGMSG("readpage_strip(0x%lx, 0x%lx) empty page,"
356 " splitting\n", inode->i_ino, page->index);
357
358 return read_exec(pcol, false);
359 }
360
361 try_again:
362
363 if (unlikely(pcol->pg_first == -1)) {
364 pcol->pg_first = page->index;
365 } else if (unlikely((pcol->pg_first + pcol->nr_pages) !=
366 page->index)) {
367 /* Discontinuity detected, split the request */
368 ret = read_exec(pcol, false);
369 if (unlikely(ret))
370 goto fail;
371 goto try_again;
372 }
373
374 if (!pcol->pages) {
375 ret = pcol_try_alloc(pcol);
376 if (unlikely(ret))
377 goto fail;
378 }
379
380 if (len != PAGE_CACHE_SIZE)
381 zero_user(page, len, PAGE_CACHE_SIZE - len);
382
383 EXOFS_DBGMSG2(" readpage_strip(0x%lx, 0x%lx) len=0x%zx\n",
384 inode->i_ino, page->index, len);
385
386 ret = pcol_add_page(pcol, page, len);
387 if (ret) {
388 EXOFS_DBGMSG2("Failed pcol_add_page pages[i]=%p "
389 "this_len=0x%zx nr_pages=%u length=0x%lx\n",
390 page, len, pcol->nr_pages, pcol->length);
391
392 /* split the request, and start again with current page */
393 ret = read_exec(pcol, false);
394 if (unlikely(ret))
395 goto fail;
396
397 goto try_again;
398 }
399
400 return 0;
401
402 fail:
403 /* SetPageError(page); ??? */
404 unlock_page(page);
405 return ret;
406 }
407
408 static int exofs_readpages(struct file *file, struct address_space *mapping,
409 struct list_head *pages, unsigned nr_pages)
410 {
411 struct page_collect pcol;
412 int ret;
413
414 _pcol_init(&pcol, nr_pages, mapping->host);
415
416 ret = read_cache_pages(mapping, pages, readpage_strip, &pcol);
417 if (ret) {
418 EXOFS_ERR("read_cache_pages => %d\n", ret);
419 return ret;
420 }
421
422 return read_exec(&pcol, false);
423 }
424
425 static int _readpage(struct page *page, bool is_sync)
426 {
427 struct page_collect pcol;
428 int ret;
429
430 _pcol_init(&pcol, 1, page->mapping->host);
431
432 /* readpage_strip might call read_exec(,is_sync==false) at several
433 * places but not if we have a single page.
434 */
435 pcol.read_4_write = is_sync;
436 ret = readpage_strip(&pcol, page);
437 if (ret) {
438 EXOFS_ERR("_readpage => %d\n", ret);
439 return ret;
440 }
441
442 return read_exec(&pcol, is_sync);
443 }
444
445 /*
446 * We don't need the file
447 */
448 static int exofs_readpage(struct file *file, struct page *page)
449 {
450 return _readpage(page, false);
451 }
452
453 /* Callback for osd_write. All writes are asynchronous */
454 static void writepages_done(struct exofs_io_state *ios, void *p)
455 {
456 struct page_collect *pcol = p;
457 int i;
458 u64 resid;
459 u64 good_bytes;
460 u64 length = 0;
461 int ret = exofs_check_io(ios, &resid);
462
463 atomic_dec(&pcol->sbi->s_curr_pending);
464
465 if (likely(!ret))
466 good_bytes = pcol->length;
467 else
468 good_bytes = pcol->length - resid;
469
470 EXOFS_DBGMSG2("writepages_done(0x%lx) good_bytes=0x%llx"
471 " length=0x%lx nr_pages=%u\n",
472 pcol->inode->i_ino, _LLU(good_bytes), pcol->length,
473 pcol->nr_pages);
474
475 for (i = 0; i < pcol->nr_pages; i++) {
476 struct page *page = pcol->pages[i];
477 struct inode *inode = page->mapping->host;
478 int page_stat;
479
480 if (inode != pcol->inode)
481 continue; /* osd might add more pages to a bio */
482
483 if (likely(length < good_bytes))
484 page_stat = 0;
485 else
486 page_stat = ret;
487
488 update_write_page(page, page_stat);
489 unlock_page(page);
490 EXOFS_DBGMSG2(" writepages_done(0x%lx, 0x%lx) status=%d\n",
491 inode->i_ino, page->index, page_stat);
492
493 length += PAGE_SIZE;
494 }
495
496 pcol_free(pcol);
497 kfree(pcol);
498 EXOFS_DBGMSG2("writepages_done END\n");
499 }
500
501 static int write_exec(struct page_collect *pcol)
502 {
503 struct exofs_i_info *oi = exofs_i(pcol->inode);
504 struct exofs_io_state *ios = pcol->ios;
505 struct page_collect *pcol_copy = NULL;
506 int ret;
507
508 if (!pcol->pages)
509 return 0;
510
511 pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL);
512 if (!pcol_copy) {
513 EXOFS_ERR("write_exec: Faild to kmalloc(pcol)\n");
514 ret = -ENOMEM;
515 goto err;
516 }
517
518 *pcol_copy = *pcol;
519
520 ios->pages = pcol_copy->pages;
521 ios->nr_pages = pcol_copy->nr_pages;
522 ios->offset = pcol_copy->pg_first << PAGE_CACHE_SHIFT;
523 ios->length = pcol_copy->length;
524 ios->done = writepages_done;
525 ios->private = pcol_copy;
526
527 ret = exofs_oi_write(oi, ios);
528 if (unlikely(ret)) {
529 EXOFS_ERR("write_exec: exofs_oi_write() Faild\n");
530 goto err;
531 }
532
533 atomic_inc(&pcol->sbi->s_curr_pending);
534 EXOFS_DBGMSG2("write_exec(0x%lx, 0x%llx) start=0x%llx length=0x%lx\n",
535 pcol->inode->i_ino, pcol->pg_first, _LLU(ios->offset),
536 pcol->length);
537 /* pages ownership was passed to pcol_copy */
538 _pcol_reset(pcol);
539 return 0;
540
541 err:
542 _unlock_pcol_pages(pcol, ret, WRITE);
543 pcol_free(pcol);
544 kfree(pcol_copy);
545
546 return ret;
547 }
548
549 /* writepage_strip is called either directly from writepage() or by the VFS from
550 * within write_cache_pages(), to add one more page to be written to storage.
551 * It will try to collect as many contiguous pages as possible. If a
552 * discontinuity is encountered or it runs out of resources it will submit the
553 * previous segment and will start a new collection.
554 * Eventually caller must submit the last segment if present.
555 */
556 static int writepage_strip(struct page *page,
557 struct writeback_control *wbc_unused, void *data)
558 {
559 struct page_collect *pcol = data;
560 struct inode *inode = pcol->inode;
561 struct exofs_i_info *oi = exofs_i(inode);
562 loff_t i_size = i_size_read(inode);
563 pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
564 size_t len;
565 int ret;
566
567 BUG_ON(!PageLocked(page));
568
569 ret = wait_obj_created(oi);
570 if (unlikely(ret))
571 goto fail;
572
573 if (page->index < end_index)
574 /* in this case, the page is within the limits of the file */
575 len = PAGE_CACHE_SIZE;
576 else {
577 len = i_size & ~PAGE_CACHE_MASK;
578
579 if (page->index > end_index || !len) {
580 /* in this case, the page is outside the limits
581 * (truncate in progress)
582 */
583 ret = write_exec(pcol);
584 if (unlikely(ret))
585 goto fail;
586 if (PageError(page))
587 ClearPageError(page);
588 unlock_page(page);
589 EXOFS_DBGMSG("writepage_strip(0x%lx, 0x%lx) "
590 "outside the limits\n",
591 inode->i_ino, page->index);
592 return 0;
593 }
594 }
595
596 try_again:
597
598 if (unlikely(pcol->pg_first == -1)) {
599 pcol->pg_first = page->index;
600 } else if (unlikely((pcol->pg_first + pcol->nr_pages) !=
601 page->index)) {
602 /* Discontinuity detected, split the request */
603 ret = write_exec(pcol);
604 if (unlikely(ret))
605 goto fail;
606
607 EXOFS_DBGMSG("writepage_strip(0x%lx, 0x%lx) Discontinuity\n",
608 inode->i_ino, page->index);
609 goto try_again;
610 }
611
612 if (!pcol->pages) {
613 ret = pcol_try_alloc(pcol);
614 if (unlikely(ret))
615 goto fail;
616 }
617
618 EXOFS_DBGMSG2(" writepage_strip(0x%lx, 0x%lx) len=0x%zx\n",
619 inode->i_ino, page->index, len);
620
621 ret = pcol_add_page(pcol, page, len);
622 if (unlikely(ret)) {
623 EXOFS_DBGMSG2("Failed pcol_add_page "
624 "nr_pages=%u total_length=0x%lx\n",
625 pcol->nr_pages, pcol->length);
626
627 /* split the request, next loop will start again */
628 ret = write_exec(pcol);
629 if (unlikely(ret)) {
630 EXOFS_DBGMSG("write_exec faild => %d", ret);
631 goto fail;
632 }
633
634 goto try_again;
635 }
636
637 BUG_ON(PageWriteback(page));
638 set_page_writeback(page);
639
640 return 0;
641
642 fail:
643 EXOFS_DBGMSG("Error: writepage_strip(0x%lx, 0x%lx)=>%d\n",
644 inode->i_ino, page->index, ret);
645 set_bit(AS_EIO, &page->mapping->flags);
646 unlock_page(page);
647 return ret;
648 }
649
650 static int exofs_writepages(struct address_space *mapping,
651 struct writeback_control *wbc)
652 {
653 struct page_collect pcol;
654 long start, end, expected_pages;
655 int ret;
656
657 start = wbc->range_start >> PAGE_CACHE_SHIFT;
658 end = (wbc->range_end == LLONG_MAX) ?
659 start + mapping->nrpages :
660 wbc->range_end >> PAGE_CACHE_SHIFT;
661
662 if (start || end)
663 expected_pages = end - start + 1;
664 else
665 expected_pages = mapping->nrpages;
666
667 if (expected_pages < 32L)
668 expected_pages = 32L;
669
670 EXOFS_DBGMSG2("inode(0x%lx) wbc->start=0x%llx wbc->end=0x%llx "
671 "nrpages=%lu start=0x%lx end=0x%lx expected_pages=%ld\n",
672 mapping->host->i_ino, wbc->range_start, wbc->range_end,
673 mapping->nrpages, start, end, expected_pages);
674
675 _pcol_init(&pcol, expected_pages, mapping->host);
676
677 ret = write_cache_pages(mapping, wbc, writepage_strip, &pcol);
678 if (ret) {
679 EXOFS_ERR("write_cache_pages => %d\n", ret);
680 return ret;
681 }
682
683 return write_exec(&pcol);
684 }
685
686 static int exofs_writepage(struct page *page, struct writeback_control *wbc)
687 {
688 struct page_collect pcol;
689 int ret;
690
691 _pcol_init(&pcol, 1, page->mapping->host);
692
693 ret = writepage_strip(page, NULL, &pcol);
694 if (ret) {
695 EXOFS_ERR("exofs_writepage => %d\n", ret);
696 return ret;
697 }
698
699 return write_exec(&pcol);
700 }
701
702 /* i_mutex held using inode->i_size directly */
703 static void _write_failed(struct inode *inode, loff_t to)
704 {
705 if (to > inode->i_size)
706 truncate_pagecache(inode, to, inode->i_size);
707 }
708
709 int exofs_write_begin(struct file *file, struct address_space *mapping,
710 loff_t pos, unsigned len, unsigned flags,
711 struct page **pagep, void **fsdata)
712 {
713 int ret = 0;
714 struct page *page;
715
716 page = *pagep;
717 if (page == NULL) {
718 ret = simple_write_begin(file, mapping, pos, len, flags, pagep,
719 fsdata);
720 if (ret) {
721 EXOFS_DBGMSG("simple_write_begin faild\n");
722 goto out;
723 }
724
725 page = *pagep;
726 }
727
728 /* read modify write */
729 if (!PageUptodate(page) && (len != PAGE_CACHE_SIZE)) {
730 ret = _readpage(page, true);
731 if (ret) {
732 /*SetPageError was done by _readpage. Is it ok?*/
733 unlock_page(page);
734 EXOFS_DBGMSG("__readpage_filler faild\n");
735 }
736 }
737 out:
738 if (unlikely(ret))
739 _write_failed(mapping->host, pos + len);
740
741 return ret;
742 }
743
744 static int exofs_write_begin_export(struct file *file,
745 struct address_space *mapping,
746 loff_t pos, unsigned len, unsigned flags,
747 struct page **pagep, void **fsdata)
748 {
749 *pagep = NULL;
750
751 return exofs_write_begin(file, mapping, pos, len, flags, pagep,
752 fsdata);
753 }
754
755 static int exofs_write_end(struct file *file, struct address_space *mapping,
756 loff_t pos, unsigned len, unsigned copied,
757 struct page *page, void *fsdata)
758 {
759 struct inode *inode = mapping->host;
760 /* According to comment in simple_write_end i_mutex is held */
761 loff_t i_size = inode->i_size;
762 int ret;
763
764 ret = simple_write_end(file, mapping,pos, len, copied, page, fsdata);
765 if (unlikely(ret))
766 _write_failed(inode, pos + len);
767
768 /* TODO: once simple_write_end marks inode dirty remove */
769 if (i_size != inode->i_size)
770 mark_inode_dirty(inode);
771 return ret;
772 }
773
774 static int exofs_releasepage(struct page *page, gfp_t gfp)
775 {
776 EXOFS_DBGMSG("page 0x%lx\n", page->index);
777 WARN_ON(1);
778 return 0;
779 }
780
781 static void exofs_invalidatepage(struct page *page, unsigned long offset)
782 {
783 EXOFS_DBGMSG("page 0x%lx offset 0x%lx\n", page->index, offset);
784 WARN_ON(1);
785 }
786
787 const struct address_space_operations exofs_aops = {
788 .readpage = exofs_readpage,
789 .readpages = exofs_readpages,
790 .writepage = exofs_writepage,
791 .writepages = exofs_writepages,
792 .write_begin = exofs_write_begin_export,
793 .write_end = exofs_write_end,
794 .releasepage = exofs_releasepage,
795 .set_page_dirty = __set_page_dirty_nobuffers,
796 .invalidatepage = exofs_invalidatepage,
797
798 /* Not implemented Yet */
799 .bmap = NULL, /* TODO: use osd's OSD_ACT_READ_MAP */
800 .direct_IO = NULL, /* TODO: Should be trivial to do */
801
802 /* With these NULL has special meaning or default is not exported */
803 .sync_page = NULL,
804 .get_xip_mem = NULL,
805 .migratepage = NULL,
806 .launder_page = NULL,
807 .is_partially_uptodate = NULL,
808 .error_remove_page = NULL,
809 };
810
811 /******************************************************************************
812 * INODE OPERATIONS
813 *****************************************************************************/
814
815 /*
816 * Test whether an inode is a fast symlink.
817 */
818 static inline int exofs_inode_is_fast_symlink(struct inode *inode)
819 {
820 struct exofs_i_info *oi = exofs_i(inode);
821
822 return S_ISLNK(inode->i_mode) && (oi->i_data[0] != 0);
823 }
824
825 const struct osd_attr g_attr_logical_length = ATTR_DEF(
826 OSD_APAGE_OBJECT_INFORMATION, OSD_ATTR_OI_LOGICAL_LENGTH, 8);
827
828 static int _do_truncate(struct inode *inode, loff_t newsize)
829 {
830 struct exofs_i_info *oi = exofs_i(inode);
831 int ret;
832
833 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
834
835 ret = exofs_oi_truncate(oi, (u64)newsize);
836 if (likely(!ret))
837 truncate_setsize(inode, newsize);
838
839 EXOFS_DBGMSG("(0x%lx) size=0x%llx ret=>%d\n",
840 inode->i_ino, newsize, ret);
841 return ret;
842 }
843
844 /*
845 * Set inode attributes - update size attribute on OSD if needed,
846 * otherwise just call generic functions.
847 */
848 int exofs_setattr(struct dentry *dentry, struct iattr *iattr)
849 {
850 struct inode *inode = dentry->d_inode;
851 int error;
852
853 /* if we are about to modify an object, and it hasn't been
854 * created yet, wait
855 */
856 error = wait_obj_created(exofs_i(inode));
857 if (unlikely(error))
858 return error;
859
860 error = inode_change_ok(inode, iattr);
861 if (unlikely(error))
862 return error;
863
864 if ((iattr->ia_valid & ATTR_SIZE) &&
865 iattr->ia_size != i_size_read(inode)) {
866 error = _do_truncate(inode, iattr->ia_size);
867 if (unlikely(error))
868 return error;
869 }
870
871 setattr_copy(inode, iattr);
872 mark_inode_dirty(inode);
873 return 0;
874 }
875
876 static const struct osd_attr g_attr_inode_file_layout = ATTR_DEF(
877 EXOFS_APAGE_FS_DATA,
878 EXOFS_ATTR_INODE_FILE_LAYOUT,
879 0);
880 static const struct osd_attr g_attr_inode_dir_layout = ATTR_DEF(
881 EXOFS_APAGE_FS_DATA,
882 EXOFS_ATTR_INODE_DIR_LAYOUT,
883 0);
884
885 /*
886 * Read the Linux inode info from the OSD, and return it as is. In exofs the
887 * inode info is in an application specific page/attribute of the osd-object.
888 */
889 static int exofs_get_inode(struct super_block *sb, struct exofs_i_info *oi,
890 struct exofs_fcb *inode)
891 {
892 struct exofs_sb_info *sbi = sb->s_fs_info;
893 struct osd_attr attrs[] = {
894 [0] = g_attr_inode_data,
895 [1] = g_attr_inode_file_layout,
896 [2] = g_attr_inode_dir_layout,
897 };
898 struct exofs_io_state *ios;
899 struct exofs_on_disk_inode_layout *layout;
900 int ret;
901
902 ret = exofs_get_io_state(&sbi->layout, &ios);
903 if (unlikely(ret)) {
904 EXOFS_ERR("%s: exofs_get_io_state failed.\n", __func__);
905 return ret;
906 }
907
908 ios->obj.id = exofs_oi_objno(oi);
909 exofs_make_credential(oi->i_cred, &ios->obj);
910 ios->cred = oi->i_cred;
911
912 attrs[1].len = exofs_on_disk_inode_layout_size(sbi->layout.s_numdevs);
913 attrs[2].len = exofs_on_disk_inode_layout_size(sbi->layout.s_numdevs);
914
915 ios->in_attr = attrs;
916 ios->in_attr_len = ARRAY_SIZE(attrs);
917
918 ret = exofs_sbi_read(ios);
919 if (unlikely(ret)) {
920 EXOFS_ERR("object(0x%llx) corrupted, return empty file=>%d\n",
921 _LLU(ios->obj.id), ret);
922 memset(inode, 0, sizeof(*inode));
923 inode->i_mode = 0040000 | (0777 & ~022);
924 /* If object is lost on target we might as well enable it's
925 * delete.
926 */
927 if ((ret == -ENOENT) || (ret == -EINVAL))
928 ret = 0;
929 goto out;
930 }
931
932 ret = extract_attr_from_ios(ios, &attrs[0]);
933 if (ret) {
934 EXOFS_ERR("%s: extract_attr of inode_data failed\n", __func__);
935 goto out;
936 }
937 WARN_ON(attrs[0].len != EXOFS_INO_ATTR_SIZE);
938 memcpy(inode, attrs[0].val_ptr, EXOFS_INO_ATTR_SIZE);
939
940 ret = extract_attr_from_ios(ios, &attrs[1]);
941 if (ret) {
942 EXOFS_ERR("%s: extract_attr of inode_data failed\n", __func__);
943 goto out;
944 }
945 if (attrs[1].len) {
946 layout = attrs[1].val_ptr;
947 if (layout->gen_func != cpu_to_le16(LAYOUT_MOVING_WINDOW)) {
948 EXOFS_ERR("%s: unsupported files layout %d\n",
949 __func__, layout->gen_func);
950 ret = -ENOTSUPP;
951 goto out;
952 }
953 }
954
955 ret = extract_attr_from_ios(ios, &attrs[2]);
956 if (ret) {
957 EXOFS_ERR("%s: extract_attr of inode_data failed\n", __func__);
958 goto out;
959 }
960 if (attrs[2].len) {
961 layout = attrs[2].val_ptr;
962 if (layout->gen_func != cpu_to_le16(LAYOUT_MOVING_WINDOW)) {
963 EXOFS_ERR("%s: unsupported meta-data layout %d\n",
964 __func__, layout->gen_func);
965 ret = -ENOTSUPP;
966 goto out;
967 }
968 }
969
970 out:
971 exofs_put_io_state(ios);
972 return ret;
973 }
974
975 static void __oi_init(struct exofs_i_info *oi)
976 {
977 init_waitqueue_head(&oi->i_wq);
978 oi->i_flags = 0;
979 }
980 /*
981 * Fill in an inode read from the OSD and set it up for use
982 */
983 struct inode *exofs_iget(struct super_block *sb, unsigned long ino)
984 {
985 struct exofs_i_info *oi;
986 struct exofs_fcb fcb;
987 struct inode *inode;
988 int ret;
989
990 inode = iget_locked(sb, ino);
991 if (!inode)
992 return ERR_PTR(-ENOMEM);
993 if (!(inode->i_state & I_NEW))
994 return inode;
995 oi = exofs_i(inode);
996 __oi_init(oi);
997
998 /* read the inode from the osd */
999 ret = exofs_get_inode(sb, oi, &fcb);
1000 if (ret)
1001 goto bad_inode;
1002
1003 set_obj_created(oi);
1004
1005 /* copy stuff from on-disk struct to in-memory struct */
1006 inode->i_mode = le16_to_cpu(fcb.i_mode);
1007 inode->i_uid = le32_to_cpu(fcb.i_uid);
1008 inode->i_gid = le32_to_cpu(fcb.i_gid);
1009 inode->i_nlink = le16_to_cpu(fcb.i_links_count);
1010 inode->i_ctime.tv_sec = (signed)le32_to_cpu(fcb.i_ctime);
1011 inode->i_atime.tv_sec = (signed)le32_to_cpu(fcb.i_atime);
1012 inode->i_mtime.tv_sec = (signed)le32_to_cpu(fcb.i_mtime);
1013 inode->i_ctime.tv_nsec =
1014 inode->i_atime.tv_nsec = inode->i_mtime.tv_nsec = 0;
1015 oi->i_commit_size = le64_to_cpu(fcb.i_size);
1016 i_size_write(inode, oi->i_commit_size);
1017 inode->i_blkbits = EXOFS_BLKSHIFT;
1018 inode->i_generation = le32_to_cpu(fcb.i_generation);
1019
1020 oi->i_dir_start_lookup = 0;
1021
1022 if ((inode->i_nlink == 0) && (inode->i_mode == 0)) {
1023 ret = -ESTALE;
1024 goto bad_inode;
1025 }
1026
1027 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1028 if (fcb.i_data[0])
1029 inode->i_rdev =
1030 old_decode_dev(le32_to_cpu(fcb.i_data[0]));
1031 else
1032 inode->i_rdev =
1033 new_decode_dev(le32_to_cpu(fcb.i_data[1]));
1034 } else {
1035 memcpy(oi->i_data, fcb.i_data, sizeof(fcb.i_data));
1036 }
1037
1038 if (S_ISREG(inode->i_mode)) {
1039 inode->i_op = &exofs_file_inode_operations;
1040 inode->i_fop = &exofs_file_operations;
1041 inode->i_mapping->a_ops = &exofs_aops;
1042 } else if (S_ISDIR(inode->i_mode)) {
1043 inode->i_op = &exofs_dir_inode_operations;
1044 inode->i_fop = &exofs_dir_operations;
1045 inode->i_mapping->a_ops = &exofs_aops;
1046 } else if (S_ISLNK(inode->i_mode)) {
1047 if (exofs_inode_is_fast_symlink(inode))
1048 inode->i_op = &exofs_fast_symlink_inode_operations;
1049 else {
1050 inode->i_op = &exofs_symlink_inode_operations;
1051 inode->i_mapping->a_ops = &exofs_aops;
1052 }
1053 } else {
1054 inode->i_op = &exofs_special_inode_operations;
1055 if (fcb.i_data[0])
1056 init_special_inode(inode, inode->i_mode,
1057 old_decode_dev(le32_to_cpu(fcb.i_data[0])));
1058 else
1059 init_special_inode(inode, inode->i_mode,
1060 new_decode_dev(le32_to_cpu(fcb.i_data[1])));
1061 }
1062
1063 unlock_new_inode(inode);
1064 return inode;
1065
1066 bad_inode:
1067 iget_failed(inode);
1068 return ERR_PTR(ret);
1069 }
1070
1071 int __exofs_wait_obj_created(struct exofs_i_info *oi)
1072 {
1073 if (!obj_created(oi)) {
1074 BUG_ON(!obj_2bcreated(oi));
1075 wait_event(oi->i_wq, obj_created(oi));
1076 }
1077 return unlikely(is_bad_inode(&oi->vfs_inode)) ? -EIO : 0;
1078 }
1079 /*
1080 * Callback function from exofs_new_inode(). The important thing is that we
1081 * set the obj_created flag so that other methods know that the object exists on
1082 * the OSD.
1083 */
1084 static void create_done(struct exofs_io_state *ios, void *p)
1085 {
1086 struct inode *inode = p;
1087 struct exofs_i_info *oi = exofs_i(inode);
1088 struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
1089 int ret;
1090
1091 ret = exofs_check_io(ios, NULL);
1092 exofs_put_io_state(ios);
1093
1094 atomic_dec(&sbi->s_curr_pending);
1095
1096 if (unlikely(ret)) {
1097 EXOFS_ERR("object=0x%llx creation faild in pid=0x%llx",
1098 _LLU(exofs_oi_objno(oi)), _LLU(sbi->layout.s_pid));
1099 /*TODO: When FS is corrupted creation can fail, object already
1100 * exist. Get rid of this asynchronous creation, if exist
1101 * increment the obj counter and try the next object. Until we
1102 * succeed. All these dangling objects will be made into lost
1103 * files by chkfs.exofs
1104 */
1105 }
1106
1107 set_obj_created(oi);
1108
1109 atomic_dec(&inode->i_count);
1110 wake_up(&oi->i_wq);
1111 }
1112
1113 /*
1114 * Set up a new inode and create an object for it on the OSD
1115 */
1116 struct inode *exofs_new_inode(struct inode *dir, int mode)
1117 {
1118 struct super_block *sb;
1119 struct inode *inode;
1120 struct exofs_i_info *oi;
1121 struct exofs_sb_info *sbi;
1122 struct exofs_io_state *ios;
1123 int ret;
1124
1125 sb = dir->i_sb;
1126 inode = new_inode(sb);
1127 if (!inode)
1128 return ERR_PTR(-ENOMEM);
1129
1130 oi = exofs_i(inode);
1131 __oi_init(oi);
1132
1133 set_obj_2bcreated(oi);
1134
1135 sbi = sb->s_fs_info;
1136
1137 sb->s_dirt = 1;
1138 inode_init_owner(inode, dir, mode);
1139 inode->i_ino = sbi->s_nextid++;
1140 inode->i_blkbits = EXOFS_BLKSHIFT;
1141 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1142 oi->i_commit_size = inode->i_size = 0;
1143 spin_lock(&sbi->s_next_gen_lock);
1144 inode->i_generation = sbi->s_next_generation++;
1145 spin_unlock(&sbi->s_next_gen_lock);
1146 insert_inode_hash(inode);
1147
1148 mark_inode_dirty(inode);
1149
1150 ret = exofs_get_io_state(&sbi->layout, &ios);
1151 if (unlikely(ret)) {
1152 EXOFS_ERR("exofs_new_inode: exofs_get_io_state failed\n");
1153 return ERR_PTR(ret);
1154 }
1155
1156 ios->obj.id = exofs_oi_objno(oi);
1157 exofs_make_credential(oi->i_cred, &ios->obj);
1158
1159 /* increment the refcount so that the inode will still be around when we
1160 * reach the callback
1161 */
1162 atomic_inc(&inode->i_count);
1163
1164 ios->done = create_done;
1165 ios->private = inode;
1166 ios->cred = oi->i_cred;
1167 ret = exofs_sbi_create(ios);
1168 if (ret) {
1169 atomic_dec(&inode->i_count);
1170 exofs_put_io_state(ios);
1171 return ERR_PTR(ret);
1172 }
1173 atomic_inc(&sbi->s_curr_pending);
1174
1175 return inode;
1176 }
1177
1178 /*
1179 * struct to pass two arguments to update_inode's callback
1180 */
1181 struct updatei_args {
1182 struct exofs_sb_info *sbi;
1183 struct exofs_fcb fcb;
1184 };
1185
1186 /*
1187 * Callback function from exofs_update_inode().
1188 */
1189 static void updatei_done(struct exofs_io_state *ios, void *p)
1190 {
1191 struct updatei_args *args = p;
1192
1193 exofs_put_io_state(ios);
1194
1195 atomic_dec(&args->sbi->s_curr_pending);
1196
1197 kfree(args);
1198 }
1199
1200 /*
1201 * Write the inode to the OSD. Just fill up the struct, and set the attribute
1202 * synchronously or asynchronously depending on the do_sync flag.
1203 */
1204 static int exofs_update_inode(struct inode *inode, int do_sync)
1205 {
1206 struct exofs_i_info *oi = exofs_i(inode);
1207 struct super_block *sb = inode->i_sb;
1208 struct exofs_sb_info *sbi = sb->s_fs_info;
1209 struct exofs_io_state *ios;
1210 struct osd_attr attr;
1211 struct exofs_fcb *fcb;
1212 struct updatei_args *args;
1213 int ret;
1214
1215 args = kzalloc(sizeof(*args), GFP_KERNEL);
1216 if (!args) {
1217 EXOFS_DBGMSG("Faild kzalloc of args\n");
1218 return -ENOMEM;
1219 }
1220
1221 fcb = &args->fcb;
1222
1223 fcb->i_mode = cpu_to_le16(inode->i_mode);
1224 fcb->i_uid = cpu_to_le32(inode->i_uid);
1225 fcb->i_gid = cpu_to_le32(inode->i_gid);
1226 fcb->i_links_count = cpu_to_le16(inode->i_nlink);
1227 fcb->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
1228 fcb->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
1229 fcb->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
1230 oi->i_commit_size = i_size_read(inode);
1231 fcb->i_size = cpu_to_le64(oi->i_commit_size);
1232 fcb->i_generation = cpu_to_le32(inode->i_generation);
1233
1234 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1235 if (old_valid_dev(inode->i_rdev)) {
1236 fcb->i_data[0] =
1237 cpu_to_le32(old_encode_dev(inode->i_rdev));
1238 fcb->i_data[1] = 0;
1239 } else {
1240 fcb->i_data[0] = 0;
1241 fcb->i_data[1] =
1242 cpu_to_le32(new_encode_dev(inode->i_rdev));
1243 fcb->i_data[2] = 0;
1244 }
1245 } else
1246 memcpy(fcb->i_data, oi->i_data, sizeof(fcb->i_data));
1247
1248 ret = exofs_get_io_state(&sbi->layout, &ios);
1249 if (unlikely(ret)) {
1250 EXOFS_ERR("%s: exofs_get_io_state failed.\n", __func__);
1251 goto free_args;
1252 }
1253
1254 attr = g_attr_inode_data;
1255 attr.val_ptr = fcb;
1256 ios->out_attr_len = 1;
1257 ios->out_attr = &attr;
1258
1259 if (!obj_created(oi)) {
1260 EXOFS_DBGMSG("!obj_created\n");
1261 BUG_ON(!obj_2bcreated(oi));
1262 wait_event(oi->i_wq, obj_created(oi));
1263 EXOFS_DBGMSG("wait_event done\n");
1264 }
1265
1266 if (!do_sync) {
1267 args->sbi = sbi;
1268 ios->done = updatei_done;
1269 ios->private = args;
1270 }
1271
1272 ret = exofs_oi_write(oi, ios);
1273 if (!do_sync && !ret) {
1274 atomic_inc(&sbi->s_curr_pending);
1275 goto out; /* deallocation in updatei_done */
1276 }
1277
1278 exofs_put_io_state(ios);
1279 free_args:
1280 kfree(args);
1281 out:
1282 EXOFS_DBGMSG("(0x%lx) do_sync=%d ret=>%d\n",
1283 inode->i_ino, do_sync, ret);
1284 return ret;
1285 }
1286
1287 int exofs_write_inode(struct inode *inode, struct writeback_control *wbc)
1288 {
1289 return exofs_update_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
1290 }
1291
1292 /*
1293 * Callback function from exofs_delete_inode() - don't have much cleaning up to
1294 * do.
1295 */
1296 static void delete_done(struct exofs_io_state *ios, void *p)
1297 {
1298 struct exofs_sb_info *sbi = p;
1299
1300 exofs_put_io_state(ios);
1301
1302 atomic_dec(&sbi->s_curr_pending);
1303 }
1304
1305 /*
1306 * Called when the refcount of an inode reaches zero. We remove the object
1307 * from the OSD here. We make sure the object was created before we try and
1308 * delete it.
1309 */
1310 void exofs_evict_inode(struct inode *inode)
1311 {
1312 struct exofs_i_info *oi = exofs_i(inode);
1313 struct super_block *sb = inode->i_sb;
1314 struct exofs_sb_info *sbi = sb->s_fs_info;
1315 struct exofs_io_state *ios;
1316 int ret;
1317
1318 truncate_inode_pages(&inode->i_data, 0);
1319
1320 /* TODO: should do better here */
1321 if (inode->i_nlink || is_bad_inode(inode))
1322 goto no_delete;
1323
1324 inode->i_size = 0;
1325 end_writeback(inode);
1326
1327 /* if we are deleting an obj that hasn't been created yet, wait */
1328 if (!obj_created(oi)) {
1329 BUG_ON(!obj_2bcreated(oi));
1330 wait_event(oi->i_wq, obj_created(oi));
1331 /* ignore the error attempt a remove anyway */
1332 }
1333
1334 /* Now Remove the OSD objects */
1335 ret = exofs_get_io_state(&sbi->layout, &ios);
1336 if (unlikely(ret)) {
1337 EXOFS_ERR("%s: exofs_get_io_state failed\n", __func__);
1338 return;
1339 }
1340
1341 ios->obj.id = exofs_oi_objno(oi);
1342 ios->done = delete_done;
1343 ios->private = sbi;
1344 ios->cred = oi->i_cred;
1345 ret = exofs_sbi_remove(ios);
1346 if (ret) {
1347 EXOFS_ERR("%s: exofs_sbi_remove failed\n", __func__);
1348 exofs_put_io_state(ios);
1349 return;
1350 }
1351 atomic_inc(&sbi->s_curr_pending);
1352
1353 return;
1354
1355 no_delete:
1356 end_writeback(inode);
1357 }
Tomato firmware and modifications.