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drm, kdb, kms: Change mode_set_base_atomic() enter argument to be an enum
[linux-2.6/libata-dev.git] / fs / exofs / inode.c
blob3eadd97324b140e679f269480b3737823fd008cb
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 /* FIXME: Just for debugging, will be removed */
333 if (PageUptodate(page))
334 EXOFS_ERR("PageUptodate(0x%lx, 0x%lx)\n", pcol->inode->i_ino,
335 page->index);
336
337 if (page->index < end_index)
338 len = PAGE_CACHE_SIZE;
339 else if (page->index == end_index)
340 len = i_size & ~PAGE_CACHE_MASK;
341 else
342 len = 0;
343
344 if (!len || !obj_created(oi)) {
345 /* this will be out of bounds, or doesn't exist yet.
346 * Current page is cleared and the request is split
347 */
348 clear_highpage(page);
349
350 SetPageUptodate(page);
351 if (PageError(page))
352 ClearPageError(page);
353
354 if (!pcol->read_4_write)
355 unlock_page(page);
356 EXOFS_DBGMSG("readpage_strip(0x%lx, 0x%lx) empty page,"
357 " splitting\n", inode->i_ino, page->index);
358
359 return read_exec(pcol, false);
360 }
361
362 try_again:
363
364 if (unlikely(pcol->pg_first == -1)) {
365 pcol->pg_first = page->index;
366 } else if (unlikely((pcol->pg_first + pcol->nr_pages) !=
367 page->index)) {
368 /* Discontinuity detected, split the request */
369 ret = read_exec(pcol, false);
370 if (unlikely(ret))
371 goto fail;
372 goto try_again;
373 }
374
375 if (!pcol->pages) {
376 ret = pcol_try_alloc(pcol);
377 if (unlikely(ret))
378 goto fail;
379 }
380
381 if (len != PAGE_CACHE_SIZE)
382 zero_user(page, len, PAGE_CACHE_SIZE - len);
383
384 EXOFS_DBGMSG2(" readpage_strip(0x%lx, 0x%lx) len=0x%zx\n",
385 inode->i_ino, page->index, len);
386
387 ret = pcol_add_page(pcol, page, len);
388 if (ret) {
389 EXOFS_DBGMSG2("Failed pcol_add_page pages[i]=%p "
390 "this_len=0x%zx nr_pages=%u length=0x%lx\n",
391 page, len, pcol->nr_pages, pcol->length);
392
393 /* split the request, and start again with current page */
394 ret = read_exec(pcol, false);
395 if (unlikely(ret))
396 goto fail;
397
398 goto try_again;
399 }
400
401 return 0;
402
403 fail:
404 /* SetPageError(page); ??? */
405 unlock_page(page);
406 return ret;
407 }
408
409 static int exofs_readpages(struct file *file, struct address_space *mapping,
410 struct list_head *pages, unsigned nr_pages)
411 {
412 struct page_collect pcol;
413 int ret;
414
415 _pcol_init(&pcol, nr_pages, mapping->host);
416
417 ret = read_cache_pages(mapping, pages, readpage_strip, &pcol);
418 if (ret) {
419 EXOFS_ERR("read_cache_pages => %d\n", ret);
420 return ret;
421 }
422
423 return read_exec(&pcol, false);
424 }
425
426 static int _readpage(struct page *page, bool is_sync)
427 {
428 struct page_collect pcol;
429 int ret;
430
431 _pcol_init(&pcol, 1, page->mapping->host);
432
433 /* readpage_strip might call read_exec(,is_sync==false) at several
434 * places but not if we have a single page.
435 */
436 pcol.read_4_write = is_sync;
437 ret = readpage_strip(&pcol, page);
438 if (ret) {
439 EXOFS_ERR("_readpage => %d\n", ret);
440 return ret;
441 }
442
443 return read_exec(&pcol, is_sync);
444 }
445
446 /*
447 * We don't need the file
448 */
449 static int exofs_readpage(struct file *file, struct page *page)
450 {
451 return _readpage(page, false);
452 }
453
454 /* Callback for osd_write. All writes are asynchronous */
455 static void writepages_done(struct exofs_io_state *ios, void *p)
456 {
457 struct page_collect *pcol = p;
458 int i;
459 u64 resid;
460 u64 good_bytes;
461 u64 length = 0;
462 int ret = exofs_check_io(ios, &resid);
463
464 atomic_dec(&pcol->sbi->s_curr_pending);
465
466 if (likely(!ret))
467 good_bytes = pcol->length;
468 else
469 good_bytes = pcol->length - resid;
470
471 EXOFS_DBGMSG2("writepages_done(0x%lx) good_bytes=0x%llx"
472 " length=0x%lx nr_pages=%u\n",
473 pcol->inode->i_ino, _LLU(good_bytes), pcol->length,
474 pcol->nr_pages);
475
476 for (i = 0; i < pcol->nr_pages; i++) {
477 struct page *page = pcol->pages[i];
478 struct inode *inode = page->mapping->host;
479 int page_stat;
480
481 if (inode != pcol->inode)
482 continue; /* osd might add more pages to a bio */
483
484 if (likely(length < good_bytes))
485 page_stat = 0;
486 else
487 page_stat = ret;
488
489 update_write_page(page, page_stat);
490 unlock_page(page);
491 EXOFS_DBGMSG2(" writepages_done(0x%lx, 0x%lx) status=%d\n",
492 inode->i_ino, page->index, page_stat);
493
494 length += PAGE_SIZE;
495 }
496
497 pcol_free(pcol);
498 kfree(pcol);
499 EXOFS_DBGMSG2("writepages_done END\n");
500 }
501
502 static int write_exec(struct page_collect *pcol)
503 {
504 struct exofs_i_info *oi = exofs_i(pcol->inode);
505 struct exofs_io_state *ios = pcol->ios;
506 struct page_collect *pcol_copy = NULL;
507 int ret;
508
509 if (!pcol->pages)
510 return 0;
511
512 pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL);
513 if (!pcol_copy) {
514 EXOFS_ERR("write_exec: Faild to kmalloc(pcol)\n");
515 ret = -ENOMEM;
516 goto err;
517 }
518
519 *pcol_copy = *pcol;
520
521 ios->pages = pcol_copy->pages;
522 ios->nr_pages = pcol_copy->nr_pages;
523 ios->offset = pcol_copy->pg_first << PAGE_CACHE_SHIFT;
524 ios->length = pcol_copy->length;
525 ios->done = writepages_done;
526 ios->private = pcol_copy;
527
528 ret = exofs_oi_write(oi, ios);
529 if (unlikely(ret)) {
530 EXOFS_ERR("write_exec: exofs_oi_write() Faild\n");
531 goto err;
532 }
533
534 atomic_inc(&pcol->sbi->s_curr_pending);
535 EXOFS_DBGMSG2("write_exec(0x%lx, 0x%llx) start=0x%llx length=0x%lx\n",
536 pcol->inode->i_ino, pcol->pg_first, _LLU(ios->offset),
537 pcol->length);
538 /* pages ownership was passed to pcol_copy */
539 _pcol_reset(pcol);
540 return 0;
541
542 err:
543 _unlock_pcol_pages(pcol, ret, WRITE);
544 pcol_free(pcol);
545 kfree(pcol_copy);
546
547 return ret;
548 }
549
550 /* writepage_strip is called either directly from writepage() or by the VFS from
551 * within write_cache_pages(), to add one more page to be written to storage.
552 * It will try to collect as many contiguous pages as possible. If a
553 * discontinuity is encountered or it runs out of resources it will submit the
554 * previous segment and will start a new collection.
555 * Eventually caller must submit the last segment if present.
556 */
557 static int writepage_strip(struct page *page,
558 struct writeback_control *wbc_unused, void *data)
559 {
560 struct page_collect *pcol = data;
561 struct inode *inode = pcol->inode;
562 struct exofs_i_info *oi = exofs_i(inode);
563 loff_t i_size = i_size_read(inode);
564 pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
565 size_t len;
566 int ret;
567
568 BUG_ON(!PageLocked(page));
569
570 ret = wait_obj_created(oi);
571 if (unlikely(ret))
572 goto fail;
573
574 if (page->index < end_index)
575 /* in this case, the page is within the limits of the file */
576 len = PAGE_CACHE_SIZE;
577 else {
578 len = i_size & ~PAGE_CACHE_MASK;
579
580 if (page->index > end_index || !len) {
581 /* in this case, the page is outside the limits
582 * (truncate in progress)
583 */
584 ret = write_exec(pcol);
585 if (unlikely(ret))
586 goto fail;
587 if (PageError(page))
588 ClearPageError(page);
589 unlock_page(page);
590 EXOFS_DBGMSG("writepage_strip(0x%lx, 0x%lx) "
591 "outside the limits\n",
592 inode->i_ino, page->index);
593 return 0;
594 }
595 }
596
597 try_again:
598
599 if (unlikely(pcol->pg_first == -1)) {
600 pcol->pg_first = page->index;
601 } else if (unlikely((pcol->pg_first + pcol->nr_pages) !=
602 page->index)) {
603 /* Discontinuity detected, split the request */
604 ret = write_exec(pcol);
605 if (unlikely(ret))
606 goto fail;
607
608 EXOFS_DBGMSG("writepage_strip(0x%lx, 0x%lx) Discontinuity\n",
609 inode->i_ino, page->index);
610 goto try_again;
611 }
612
613 if (!pcol->pages) {
614 ret = pcol_try_alloc(pcol);
615 if (unlikely(ret))
616 goto fail;
617 }
618
619 EXOFS_DBGMSG2(" writepage_strip(0x%lx, 0x%lx) len=0x%zx\n",
620 inode->i_ino, page->index, len);
621
622 ret = pcol_add_page(pcol, page, len);
623 if (unlikely(ret)) {
624 EXOFS_DBGMSG2("Failed pcol_add_page "
625 "nr_pages=%u total_length=0x%lx\n",
626 pcol->nr_pages, pcol->length);
627
628 /* split the request, next loop will start again */
629 ret = write_exec(pcol);
630 if (unlikely(ret)) {
631 EXOFS_DBGMSG("write_exec faild => %d", ret);
632 goto fail;
633 }
634
635 goto try_again;
636 }
637
638 BUG_ON(PageWriteback(page));
639 set_page_writeback(page);
640
641 return 0;
642
643 fail:
644 EXOFS_DBGMSG("Error: writepage_strip(0x%lx, 0x%lx)=>%d\n",
645 inode->i_ino, page->index, ret);
646 set_bit(AS_EIO, &page->mapping->flags);
647 unlock_page(page);
648 return ret;
649 }
650
651 static int exofs_writepages(struct address_space *mapping,
652 struct writeback_control *wbc)
653 {
654 struct page_collect pcol;
655 long start, end, expected_pages;
656 int ret;
657
658 start = wbc->range_start >> PAGE_CACHE_SHIFT;
659 end = (wbc->range_end == LLONG_MAX) ?
660 start + mapping->nrpages :
661 wbc->range_end >> PAGE_CACHE_SHIFT;
662
663 if (start || end)
664 expected_pages = end - start + 1;
665 else
666 expected_pages = mapping->nrpages;
667
668 if (expected_pages < 32L)
669 expected_pages = 32L;
670
671 EXOFS_DBGMSG2("inode(0x%lx) wbc->start=0x%llx wbc->end=0x%llx "
672 "nrpages=%lu start=0x%lx end=0x%lx expected_pages=%ld\n",
673 mapping->host->i_ino, wbc->range_start, wbc->range_end,
674 mapping->nrpages, start, end, expected_pages);
675
676 _pcol_init(&pcol, expected_pages, mapping->host);
677
678 ret = write_cache_pages(mapping, wbc, writepage_strip, &pcol);
679 if (ret) {
680 EXOFS_ERR("write_cache_pages => %d\n", ret);
681 return ret;
682 }
683
684 return write_exec(&pcol);
685 }
686
687 static int exofs_writepage(struct page *page, struct writeback_control *wbc)
688 {
689 struct page_collect pcol;
690 int ret;
691
692 _pcol_init(&pcol, 1, page->mapping->host);
693
694 ret = writepage_strip(page, NULL, &pcol);
695 if (ret) {
696 EXOFS_ERR("exofs_writepage => %d\n", ret);
697 return ret;
698 }
699
700 return write_exec(&pcol);
701 }
702
703 /* i_mutex held using inode->i_size directly */
704 static void _write_failed(struct inode *inode, loff_t to)
705 {
706 if (to > inode->i_size)
707 truncate_pagecache(inode, to, inode->i_size);
708 }
709
710 int exofs_write_begin(struct file *file, struct address_space *mapping,
711 loff_t pos, unsigned len, unsigned flags,
712 struct page **pagep, void **fsdata)
713 {
714 int ret = 0;
715 struct page *page;
716
717 page = *pagep;
718 if (page == NULL) {
719 ret = simple_write_begin(file, mapping, pos, len, flags, pagep,
720 fsdata);
721 if (ret) {
722 EXOFS_DBGMSG("simple_write_begin faild\n");
723 goto out;
724 }
725
726 page = *pagep;
727 }
728
729 /* read modify write */
730 if (!PageUptodate(page) && (len != PAGE_CACHE_SIZE)) {
731 ret = _readpage(page, true);
732 if (ret) {
733 /*SetPageError was done by _readpage. Is it ok?*/
734 unlock_page(page);
735 EXOFS_DBGMSG("__readpage_filler faild\n");
736 }
737 }
738 out:
739 if (unlikely(ret))
740 _write_failed(mapping->host, pos + len);
741
742 return ret;
743 }
744
745 static int exofs_write_begin_export(struct file *file,
746 struct address_space *mapping,
747 loff_t pos, unsigned len, unsigned flags,
748 struct page **pagep, void **fsdata)
749 {
750 *pagep = NULL;
751
752 return exofs_write_begin(file, mapping, pos, len, flags, pagep,
753 fsdata);
754 }
755
756 static int exofs_write_end(struct file *file, struct address_space *mapping,
757 loff_t pos, unsigned len, unsigned copied,
758 struct page *page, void *fsdata)
759 {
760 struct inode *inode = mapping->host;
761 /* According to comment in simple_write_end i_mutex is held */
762 loff_t i_size = inode->i_size;
763 int ret;
764
765 ret = simple_write_end(file, mapping,pos, len, copied, page, fsdata);
766 if (unlikely(ret))
767 _write_failed(inode, pos + len);
768
769 /* TODO: once simple_write_end marks inode dirty remove */
770 if (i_size != inode->i_size)
771 mark_inode_dirty(inode);
772 return ret;
773 }
774
775 static int exofs_releasepage(struct page *page, gfp_t gfp)
776 {
777 EXOFS_DBGMSG("page 0x%lx\n", page->index);
778 WARN_ON(1);
779 return 0;
780 }
781
782 static void exofs_invalidatepage(struct page *page, unsigned long offset)
783 {
784 EXOFS_DBGMSG("page 0x%lx offset 0x%lx\n", page->index, offset);
785 WARN_ON(1);
786 }
787
788 const struct address_space_operations exofs_aops = {
789 .readpage = exofs_readpage,
790 .readpages = exofs_readpages,
791 .writepage = exofs_writepage,
792 .writepages = exofs_writepages,
793 .write_begin = exofs_write_begin_export,
794 .write_end = exofs_write_end,
795 .releasepage = exofs_releasepage,
796 .set_page_dirty = __set_page_dirty_nobuffers,
797 .invalidatepage = exofs_invalidatepage,
798
799 /* Not implemented Yet */
800 .bmap = NULL, /* TODO: use osd's OSD_ACT_READ_MAP */
801 .direct_IO = NULL, /* TODO: Should be trivial to do */
802
803 /* With these NULL has special meaning or default is not exported */
804 .sync_page = NULL,
805 .get_xip_mem = NULL,
806 .migratepage = NULL,
807 .launder_page = NULL,
808 .is_partially_uptodate = NULL,
809 .error_remove_page = NULL,
810 };
811
812 /******************************************************************************
813 * INODE OPERATIONS
814 *****************************************************************************/
815
816 /*
817 * Test whether an inode is a fast symlink.
818 */
819 static inline int exofs_inode_is_fast_symlink(struct inode *inode)
820 {
821 struct exofs_i_info *oi = exofs_i(inode);
822
823 return S_ISLNK(inode->i_mode) && (oi->i_data[0] != 0);
824 }
825
826 const struct osd_attr g_attr_logical_length = ATTR_DEF(
827 OSD_APAGE_OBJECT_INFORMATION, OSD_ATTR_OI_LOGICAL_LENGTH, 8);
828
829 static int _do_truncate(struct inode *inode, loff_t newsize)
830 {
831 struct exofs_i_info *oi = exofs_i(inode);
832 int ret;
833
834 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
835
836 ret = exofs_oi_truncate(oi, (u64)newsize);
837 if (likely(!ret))
838 truncate_setsize(inode, newsize);
839
840 EXOFS_DBGMSG("(0x%lx) size=0x%llx ret=>%d\n",
841 inode->i_ino, newsize, ret);
842 return ret;
843 }
844
845 /*
846 * Set inode attributes - update size attribute on OSD if needed,
847 * otherwise just call generic functions.
848 */
849 int exofs_setattr(struct dentry *dentry, struct iattr *iattr)
850 {
851 struct inode *inode = dentry->d_inode;
852 int error;
853
854 /* if we are about to modify an object, and it hasn't been
855 * created yet, wait
856 */
857 error = wait_obj_created(exofs_i(inode));
858 if (unlikely(error))
859 return error;
860
861 error = inode_change_ok(inode, iattr);
862 if (unlikely(error))
863 return error;
864
865 if ((iattr->ia_valid & ATTR_SIZE) &&
866 iattr->ia_size != i_size_read(inode)) {
867 error = _do_truncate(inode, iattr->ia_size);
868 if (unlikely(error))
869 return error;
870 }
871
872 setattr_copy(inode, iattr);
873 mark_inode_dirty(inode);
874 return 0;
875 }
876
877 static const struct osd_attr g_attr_inode_file_layout = ATTR_DEF(
878 EXOFS_APAGE_FS_DATA,
879 EXOFS_ATTR_INODE_FILE_LAYOUT,
880 0);
881 static const struct osd_attr g_attr_inode_dir_layout = ATTR_DEF(
882 EXOFS_APAGE_FS_DATA,
883 EXOFS_ATTR_INODE_DIR_LAYOUT,
884 0);
885
886 /*
887 * Read the Linux inode info from the OSD, and return it as is. In exofs the
888 * inode info is in an application specific page/attribute of the osd-object.
889 */
890 static int exofs_get_inode(struct super_block *sb, struct exofs_i_info *oi,
891 struct exofs_fcb *inode)
892 {
893 struct exofs_sb_info *sbi = sb->s_fs_info;
894 struct osd_attr attrs[] = {
895 [0] = g_attr_inode_data,
896 [1] = g_attr_inode_file_layout,
897 [2] = g_attr_inode_dir_layout,
898 };
899 struct exofs_io_state *ios;
900 struct exofs_on_disk_inode_layout *layout;
901 int ret;
902
903 ret = exofs_get_io_state(&sbi->layout, &ios);
904 if (unlikely(ret)) {
905 EXOFS_ERR("%s: exofs_get_io_state failed.\n", __func__);
906 return ret;
907 }
908
909 ios->obj.id = exofs_oi_objno(oi);
910 exofs_make_credential(oi->i_cred, &ios->obj);
911 ios->cred = oi->i_cred;
912
913 attrs[1].len = exofs_on_disk_inode_layout_size(sbi->layout.s_numdevs);
914 attrs[2].len = exofs_on_disk_inode_layout_size(sbi->layout.s_numdevs);
915
916 ios->in_attr = attrs;
917 ios->in_attr_len = ARRAY_SIZE(attrs);
918
919 ret = exofs_sbi_read(ios);
920 if (unlikely(ret)) {
921 EXOFS_ERR("object(0x%llx) corrupted, return empty file=>%d\n",
922 _LLU(ios->obj.id), ret);
923 memset(inode, 0, sizeof(*inode));
924 inode->i_mode = 0040000 | (0777 & ~022);
925 /* If object is lost on target we might as well enable it's
926 * delete.
927 */
928 if ((ret == -ENOENT) || (ret == -EINVAL))
929 ret = 0;
930 goto out;
931 }
932
933 ret = extract_attr_from_ios(ios, &attrs[0]);
934 if (ret) {
935 EXOFS_ERR("%s: extract_attr of inode_data failed\n", __func__);
936 goto out;
937 }
938 WARN_ON(attrs[0].len != EXOFS_INO_ATTR_SIZE);
939 memcpy(inode, attrs[0].val_ptr, EXOFS_INO_ATTR_SIZE);
940
941 ret = extract_attr_from_ios(ios, &attrs[1]);
942 if (ret) {
943 EXOFS_ERR("%s: extract_attr of inode_data failed\n", __func__);
944 goto out;
945 }
946 if (attrs[1].len) {
947 layout = attrs[1].val_ptr;
948 if (layout->gen_func != cpu_to_le16(LAYOUT_MOVING_WINDOW)) {
949 EXOFS_ERR("%s: unsupported files layout %d\n",
950 __func__, layout->gen_func);
951 ret = -ENOTSUPP;
952 goto out;
953 }
954 }
955
956 ret = extract_attr_from_ios(ios, &attrs[2]);
957 if (ret) {
958 EXOFS_ERR("%s: extract_attr of inode_data failed\n", __func__);
959 goto out;
960 }
961 if (attrs[2].len) {
962 layout = attrs[2].val_ptr;
963 if (layout->gen_func != cpu_to_le16(LAYOUT_MOVING_WINDOW)) {
964 EXOFS_ERR("%s: unsupported meta-data layout %d\n",
965 __func__, layout->gen_func);
966 ret = -ENOTSUPP;
967 goto out;
968 }
969 }
970
971 out:
972 exofs_put_io_state(ios);
973 return ret;
974 }
975
976 static void __oi_init(struct exofs_i_info *oi)
977 {
978 init_waitqueue_head(&oi->i_wq);
979 oi->i_flags = 0;
980 }
981 /*
982 * Fill in an inode read from the OSD and set it up for use
983 */
984 struct inode *exofs_iget(struct super_block *sb, unsigned long ino)
985 {
986 struct exofs_i_info *oi;
987 struct exofs_fcb fcb;
988 struct inode *inode;
989 int ret;
990
991 inode = iget_locked(sb, ino);
992 if (!inode)
993 return ERR_PTR(-ENOMEM);
994 if (!(inode->i_state & I_NEW))
995 return inode;
996 oi = exofs_i(inode);
997 __oi_init(oi);
998
999 /* read the inode from the osd */
1000 ret = exofs_get_inode(sb, oi, &fcb);
1001 if (ret)
1002 goto bad_inode;
1003
1004 set_obj_created(oi);
1005
1006 /* copy stuff from on-disk struct to in-memory struct */
1007 inode->i_mode = le16_to_cpu(fcb.i_mode);
1008 inode->i_uid = le32_to_cpu(fcb.i_uid);
1009 inode->i_gid = le32_to_cpu(fcb.i_gid);
1010 inode->i_nlink = le16_to_cpu(fcb.i_links_count);
1011 inode->i_ctime.tv_sec = (signed)le32_to_cpu(fcb.i_ctime);
1012 inode->i_atime.tv_sec = (signed)le32_to_cpu(fcb.i_atime);
1013 inode->i_mtime.tv_sec = (signed)le32_to_cpu(fcb.i_mtime);
1014 inode->i_ctime.tv_nsec =
1015 inode->i_atime.tv_nsec = inode->i_mtime.tv_nsec = 0;
1016 oi->i_commit_size = le64_to_cpu(fcb.i_size);
1017 i_size_write(inode, oi->i_commit_size);
1018 inode->i_blkbits = EXOFS_BLKSHIFT;
1019 inode->i_generation = le32_to_cpu(fcb.i_generation);
1020
1021 oi->i_dir_start_lookup = 0;
1022
1023 if ((inode->i_nlink == 0) && (inode->i_mode == 0)) {
1024 ret = -ESTALE;
1025 goto bad_inode;
1026 }
1027
1028 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1029 if (fcb.i_data[0])
1030 inode->i_rdev =
1031 old_decode_dev(le32_to_cpu(fcb.i_data[0]));
1032 else
1033 inode->i_rdev =
1034 new_decode_dev(le32_to_cpu(fcb.i_data[1]));
1035 } else {
1036 memcpy(oi->i_data, fcb.i_data, sizeof(fcb.i_data));
1037 }
1038
1039 if (S_ISREG(inode->i_mode)) {
1040 inode->i_op = &exofs_file_inode_operations;
1041 inode->i_fop = &exofs_file_operations;
1042 inode->i_mapping->a_ops = &exofs_aops;
1043 } else if (S_ISDIR(inode->i_mode)) {
1044 inode->i_op = &exofs_dir_inode_operations;
1045 inode->i_fop = &exofs_dir_operations;
1046 inode->i_mapping->a_ops = &exofs_aops;
1047 } else if (S_ISLNK(inode->i_mode)) {
1048 if (exofs_inode_is_fast_symlink(inode))
1049 inode->i_op = &exofs_fast_symlink_inode_operations;
1050 else {
1051 inode->i_op = &exofs_symlink_inode_operations;
1052 inode->i_mapping->a_ops = &exofs_aops;
1053 }
1054 } else {
1055 inode->i_op = &exofs_special_inode_operations;
1056 if (fcb.i_data[0])
1057 init_special_inode(inode, inode->i_mode,
1058 old_decode_dev(le32_to_cpu(fcb.i_data[0])));
1059 else
1060 init_special_inode(inode, inode->i_mode,
1061 new_decode_dev(le32_to_cpu(fcb.i_data[1])));
1062 }
1063
1064 unlock_new_inode(inode);
1065 return inode;
1066
1067 bad_inode:
1068 iget_failed(inode);
1069 return ERR_PTR(ret);
1070 }
1071
1072 int __exofs_wait_obj_created(struct exofs_i_info *oi)
1073 {
1074 if (!obj_created(oi)) {
1075 BUG_ON(!obj_2bcreated(oi));
1076 wait_event(oi->i_wq, obj_created(oi));
1077 }
1078 return unlikely(is_bad_inode(&oi->vfs_inode)) ? -EIO : 0;
1079 }
1080 /*
1081 * Callback function from exofs_new_inode(). The important thing is that we
1082 * set the obj_created flag so that other methods know that the object exists on
1083 * the OSD.
1084 */
1085 static void create_done(struct exofs_io_state *ios, void *p)
1086 {
1087 struct inode *inode = p;
1088 struct exofs_i_info *oi = exofs_i(inode);
1089 struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
1090 int ret;
1091
1092 ret = exofs_check_io(ios, NULL);
1093 exofs_put_io_state(ios);
1094
1095 atomic_dec(&sbi->s_curr_pending);
1096
1097 if (unlikely(ret)) {
1098 EXOFS_ERR("object=0x%llx creation faild in pid=0x%llx",
1099 _LLU(exofs_oi_objno(oi)), _LLU(sbi->layout.s_pid));
1100 /*TODO: When FS is corrupted creation can fail, object already
1101 * exist. Get rid of this asynchronous creation, if exist
1102 * increment the obj counter and try the next object. Until we
1103 * succeed. All these dangling objects will be made into lost
1104 * files by chkfs.exofs
1105 */
1106 }
1107
1108 set_obj_created(oi);
1109
1110 atomic_dec(&inode->i_count);
1111 wake_up(&oi->i_wq);
1112 }
1113
1114 /*
1115 * Set up a new inode and create an object for it on the OSD
1116 */
1117 struct inode *exofs_new_inode(struct inode *dir, int mode)
1118 {
1119 struct super_block *sb;
1120 struct inode *inode;
1121 struct exofs_i_info *oi;
1122 struct exofs_sb_info *sbi;
1123 struct exofs_io_state *ios;
1124 int ret;
1125
1126 sb = dir->i_sb;
1127 inode = new_inode(sb);
1128 if (!inode)
1129 return ERR_PTR(-ENOMEM);
1130
1131 oi = exofs_i(inode);
1132 __oi_init(oi);
1133
1134 set_obj_2bcreated(oi);
1135
1136 sbi = sb->s_fs_info;
1137
1138 sb->s_dirt = 1;
1139 inode_init_owner(inode, dir, mode);
1140 inode->i_ino = sbi->s_nextid++;
1141 inode->i_blkbits = EXOFS_BLKSHIFT;
1142 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1143 oi->i_commit_size = inode->i_size = 0;
1144 spin_lock(&sbi->s_next_gen_lock);
1145 inode->i_generation = sbi->s_next_generation++;
1146 spin_unlock(&sbi->s_next_gen_lock);
1147 insert_inode_hash(inode);
1148
1149 mark_inode_dirty(inode);
1150
1151 ret = exofs_get_io_state(&sbi->layout, &ios);
1152 if (unlikely(ret)) {
1153 EXOFS_ERR("exofs_new_inode: exofs_get_io_state failed\n");
1154 return ERR_PTR(ret);
1155 }
1156
1157 ios->obj.id = exofs_oi_objno(oi);
1158 exofs_make_credential(oi->i_cred, &ios->obj);
1159
1160 /* increment the refcount so that the inode will still be around when we
1161 * reach the callback
1162 */
1163 atomic_inc(&inode->i_count);
1164
1165 ios->done = create_done;
1166 ios->private = inode;
1167 ios->cred = oi->i_cred;
1168 ret = exofs_sbi_create(ios);
1169 if (ret) {
1170 atomic_dec(&inode->i_count);
1171 exofs_put_io_state(ios);
1172 return ERR_PTR(ret);
1173 }
1174 atomic_inc(&sbi->s_curr_pending);
1175
1176 return inode;
1177 }
1178
1179 /*
1180 * struct to pass two arguments to update_inode's callback
1181 */
1182 struct updatei_args {
1183 struct exofs_sb_info *sbi;
1184 struct exofs_fcb fcb;
1185 };
1186
1187 /*
1188 * Callback function from exofs_update_inode().
1189 */
1190 static void updatei_done(struct exofs_io_state *ios, void *p)
1191 {
1192 struct updatei_args *args = p;
1193
1194 exofs_put_io_state(ios);
1195
1196 atomic_dec(&args->sbi->s_curr_pending);
1197
1198 kfree(args);
1199 }
1200
1201 /*
1202 * Write the inode to the OSD. Just fill up the struct, and set the attribute
1203 * synchronously or asynchronously depending on the do_sync flag.
1204 */
1205 static int exofs_update_inode(struct inode *inode, int do_sync)
1206 {
1207 struct exofs_i_info *oi = exofs_i(inode);
1208 struct super_block *sb = inode->i_sb;
1209 struct exofs_sb_info *sbi = sb->s_fs_info;
1210 struct exofs_io_state *ios;
1211 struct osd_attr attr;
1212 struct exofs_fcb *fcb;
1213 struct updatei_args *args;
1214 int ret;
1215
1216 args = kzalloc(sizeof(*args), GFP_KERNEL);
1217 if (!args) {
1218 EXOFS_DBGMSG("Faild kzalloc of args\n");
1219 return -ENOMEM;
1220 }
1221
1222 fcb = &args->fcb;
1223
1224 fcb->i_mode = cpu_to_le16(inode->i_mode);
1225 fcb->i_uid = cpu_to_le32(inode->i_uid);
1226 fcb->i_gid = cpu_to_le32(inode->i_gid);
1227 fcb->i_links_count = cpu_to_le16(inode->i_nlink);
1228 fcb->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
1229 fcb->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
1230 fcb->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
1231 oi->i_commit_size = i_size_read(inode);
1232 fcb->i_size = cpu_to_le64(oi->i_commit_size);
1233 fcb->i_generation = cpu_to_le32(inode->i_generation);
1234
1235 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1236 if (old_valid_dev(inode->i_rdev)) {
1237 fcb->i_data[0] =
1238 cpu_to_le32(old_encode_dev(inode->i_rdev));
1239 fcb->i_data[1] = 0;
1240 } else {
1241 fcb->i_data[0] = 0;
1242 fcb->i_data[1] =
1243 cpu_to_le32(new_encode_dev(inode->i_rdev));
1244 fcb->i_data[2] = 0;
1245 }
1246 } else
1247 memcpy(fcb->i_data, oi->i_data, sizeof(fcb->i_data));
1248
1249 ret = exofs_get_io_state(&sbi->layout, &ios);
1250 if (unlikely(ret)) {
1251 EXOFS_ERR("%s: exofs_get_io_state failed.\n", __func__);
1252 goto free_args;
1253 }
1254
1255 attr = g_attr_inode_data;
1256 attr.val_ptr = fcb;
1257 ios->out_attr_len = 1;
1258 ios->out_attr = &attr;
1259
1260 if (!obj_created(oi)) {
1261 EXOFS_DBGMSG("!obj_created\n");
1262 BUG_ON(!obj_2bcreated(oi));
1263 wait_event(oi->i_wq, obj_created(oi));
1264 EXOFS_DBGMSG("wait_event done\n");
1265 }
1266
1267 if (!do_sync) {
1268 args->sbi = sbi;
1269 ios->done = updatei_done;
1270 ios->private = args;
1271 }
1272
1273 ret = exofs_oi_write(oi, ios);
1274 if (!do_sync && !ret) {
1275 atomic_inc(&sbi->s_curr_pending);
1276 goto out; /* deallocation in updatei_done */
1277 }
1278
1279 exofs_put_io_state(ios);
1280 free_args:
1281 kfree(args);
1282 out:
1283 EXOFS_DBGMSG("(0x%lx) do_sync=%d ret=>%d\n",
1284 inode->i_ino, do_sync, ret);
1285 return ret;
1286 }
1287
1288 int exofs_write_inode(struct inode *inode, struct writeback_control *wbc)
1289 {
1290 return exofs_update_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
1291 }
1292
1293 /*
1294 * Callback function from exofs_delete_inode() - don't have much cleaning up to
1295 * do.
1296 */
1297 static void delete_done(struct exofs_io_state *ios, void *p)
1298 {
1299 struct exofs_sb_info *sbi = p;
1300
1301 exofs_put_io_state(ios);
1302
1303 atomic_dec(&sbi->s_curr_pending);
1304 }
1305
1306 /*
1307 * Called when the refcount of an inode reaches zero. We remove the object
1308 * from the OSD here. We make sure the object was created before we try and
1309 * delete it.
1310 */
1311 void exofs_evict_inode(struct inode *inode)
1312 {
1313 struct exofs_i_info *oi = exofs_i(inode);
1314 struct super_block *sb = inode->i_sb;
1315 struct exofs_sb_info *sbi = sb->s_fs_info;
1316 struct exofs_io_state *ios;
1317 int ret;
1318
1319 truncate_inode_pages(&inode->i_data, 0);
1320
1321 /* TODO: should do better here */
1322 if (inode->i_nlink || is_bad_inode(inode))
1323 goto no_delete;
1324
1325 inode->i_size = 0;
1326 end_writeback(inode);
1327
1328 /* if we are deleting an obj that hasn't been created yet, wait */
1329 if (!obj_created(oi)) {
1330 BUG_ON(!obj_2bcreated(oi));
1331 wait_event(oi->i_wq, obj_created(oi));
1332 /* ignore the error attempt a remove anyway */
1333 }
1334
1335 /* Now Remove the OSD objects */
1336 ret = exofs_get_io_state(&sbi->layout, &ios);
1337 if (unlikely(ret)) {
1338 EXOFS_ERR("%s: exofs_get_io_state failed\n", __func__);
1339 return;
1340 }
1341
1342 ios->obj.id = exofs_oi_objno(oi);
1343 ios->done = delete_done;
1344 ios->private = sbi;
1345 ios->cred = oi->i_cred;
1346 ret = exofs_sbi_remove(ios);
1347 if (ret) {
1348 EXOFS_ERR("%s: exofs_sbi_remove failed\n", __func__);
1349 exofs_put_io_state(ios);
1350 return;
1351 }
1352 atomic_inc(&sbi->s_curr_pending);
1353
1354 return;
1355
1356 no_delete:
1357 end_writeback(inode);
1358 }
Linux 2.6 libata-dev (mirror)