ARM: 7747/1: pcpu: ensure __my_cpu_offset cannot be re-ordered across barrier()
[linux/fpc-iii.git] / fs / exofs / inode.c
blobd1f80abd8828fcf3d8adadea9246effef03b7e29
1 /*
2 * Copyright (C) 2005, 2006
3 * Avishay Traeger (avishay@gmail.com)
4 * Copyright (C) 2008, 2009
5 * Boaz Harrosh <bharrosh@panasas.com>
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
16 * This file is part of exofs.
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.
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.
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
34 #include <linux/slab.h>
36 #include "exofs.h"
38 #define EXOFS_DBGMSG2(M...) do {} while (0)
40 unsigned exofs_max_io_pages(struct ore_layout *layout,
41 unsigned expected_pages)
43 unsigned pages = min_t(unsigned, expected_pages,
44 layout->max_io_length / PAGE_SIZE);
46 return pages;
49 struct page_collect {
50 struct exofs_sb_info *sbi;
51 struct inode *inode;
52 unsigned expected_pages;
53 struct ore_io_state *ios;
55 struct page **pages;
56 unsigned alloc_pages;
57 unsigned nr_pages;
58 unsigned long length;
59 loff_t pg_first; /* keep 64bit also in 32-arches */
60 bool read_4_write; /* This means two things: that the read is sync
61 * And the pages should not be unlocked.
63 struct page *that_locked_page;
66 static void _pcol_init(struct page_collect *pcol, unsigned expected_pages,
67 struct inode *inode)
69 struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
71 pcol->sbi = sbi;
72 pcol->inode = inode;
73 pcol->expected_pages = expected_pages;
75 pcol->ios = NULL;
76 pcol->pages = NULL;
77 pcol->alloc_pages = 0;
78 pcol->nr_pages = 0;
79 pcol->length = 0;
80 pcol->pg_first = -1;
81 pcol->read_4_write = false;
82 pcol->that_locked_page = NULL;
85 static void _pcol_reset(struct page_collect *pcol)
87 pcol->expected_pages -= min(pcol->nr_pages, pcol->expected_pages);
89 pcol->pages = NULL;
90 pcol->alloc_pages = 0;
91 pcol->nr_pages = 0;
92 pcol->length = 0;
93 pcol->pg_first = -1;
94 pcol->ios = NULL;
95 pcol->that_locked_page = NULL;
97 /* this is probably the end of the loop but in writes
98 * it might not end here. don't be left with nothing
100 if (!pcol->expected_pages)
101 pcol->expected_pages =
102 exofs_max_io_pages(&pcol->sbi->layout, ~0);
105 static int pcol_try_alloc(struct page_collect *pcol)
107 unsigned pages;
109 /* TODO: easily support bio chaining */
110 pages = exofs_max_io_pages(&pcol->sbi->layout, pcol->expected_pages);
112 for (; pages; pages >>= 1) {
113 pcol->pages = kmalloc(pages * sizeof(struct page *),
114 GFP_KERNEL);
115 if (likely(pcol->pages)) {
116 pcol->alloc_pages = pages;
117 return 0;
121 EXOFS_ERR("Failed to kmalloc expected_pages=%u\n",
122 pcol->expected_pages);
123 return -ENOMEM;
126 static void pcol_free(struct page_collect *pcol)
128 kfree(pcol->pages);
129 pcol->pages = NULL;
131 if (pcol->ios) {
132 ore_put_io_state(pcol->ios);
133 pcol->ios = NULL;
137 static int pcol_add_page(struct page_collect *pcol, struct page *page,
138 unsigned len)
140 if (unlikely(pcol->nr_pages >= pcol->alloc_pages))
141 return -ENOMEM;
143 pcol->pages[pcol->nr_pages++] = page;
144 pcol->length += len;
145 return 0;
148 enum {PAGE_WAS_NOT_IN_IO = 17};
149 static int update_read_page(struct page *page, int ret)
151 switch (ret) {
152 case 0:
153 /* Everything is OK */
154 SetPageUptodate(page);
155 if (PageError(page))
156 ClearPageError(page);
157 break;
158 case -EFAULT:
159 /* In this case we were trying to read something that wasn't on
160 * disk yet - return a page full of zeroes. This should be OK,
161 * because the object should be empty (if there was a write
162 * before this read, the read would be waiting with the page
163 * locked */
164 clear_highpage(page);
166 SetPageUptodate(page);
167 if (PageError(page))
168 ClearPageError(page);
169 EXOFS_DBGMSG("recovered read error\n");
170 /* fall through */
171 case PAGE_WAS_NOT_IN_IO:
172 ret = 0; /* recovered error */
173 break;
174 default:
175 SetPageError(page);
177 return ret;
180 static void update_write_page(struct page *page, int ret)
182 if (unlikely(ret == PAGE_WAS_NOT_IN_IO))
183 return; /* don't pass start don't collect $200 */
185 if (ret) {
186 mapping_set_error(page->mapping, ret);
187 SetPageError(page);
189 end_page_writeback(page);
192 /* Called at the end of reads, to optionally unlock pages and update their
193 * status.
195 static int __readpages_done(struct page_collect *pcol)
197 int i;
198 u64 good_bytes;
199 u64 length = 0;
200 int ret = ore_check_io(pcol->ios, NULL);
202 if (likely(!ret)) {
203 good_bytes = pcol->length;
204 ret = PAGE_WAS_NOT_IN_IO;
205 } else {
206 good_bytes = 0;
209 EXOFS_DBGMSG2("readpages_done(0x%lx) good_bytes=0x%llx"
210 " length=0x%lx nr_pages=%u\n",
211 pcol->inode->i_ino, _LLU(good_bytes), pcol->length,
212 pcol->nr_pages);
214 for (i = 0; i < pcol->nr_pages; i++) {
215 struct page *page = pcol->pages[i];
216 struct inode *inode = page->mapping->host;
217 int page_stat;
219 if (inode != pcol->inode)
220 continue; /* osd might add more pages at end */
222 if (likely(length < good_bytes))
223 page_stat = 0;
224 else
225 page_stat = ret;
227 EXOFS_DBGMSG2(" readpages_done(0x%lx, 0x%lx) %s\n",
228 inode->i_ino, page->index,
229 page_stat ? "bad_bytes" : "good_bytes");
231 ret = update_read_page(page, page_stat);
232 if (!pcol->read_4_write)
233 unlock_page(page);
234 length += PAGE_SIZE;
237 pcol_free(pcol);
238 EXOFS_DBGMSG2("readpages_done END\n");
239 return ret;
242 /* callback of async reads */
243 static void readpages_done(struct ore_io_state *ios, void *p)
245 struct page_collect *pcol = p;
247 __readpages_done(pcol);
248 atomic_dec(&pcol->sbi->s_curr_pending);
249 kfree(pcol);
252 static void _unlock_pcol_pages(struct page_collect *pcol, int ret, int rw)
254 int i;
256 for (i = 0; i < pcol->nr_pages; i++) {
257 struct page *page = pcol->pages[i];
259 if (rw == READ)
260 update_read_page(page, ret);
261 else
262 update_write_page(page, ret);
264 unlock_page(page);
268 static int _maybe_not_all_in_one_io(struct ore_io_state *ios,
269 struct page_collect *pcol_src, struct page_collect *pcol)
271 /* length was wrong or offset was not page aligned */
272 BUG_ON(pcol_src->nr_pages < ios->nr_pages);
274 if (pcol_src->nr_pages > ios->nr_pages) {
275 struct page **src_page;
276 unsigned pages_less = pcol_src->nr_pages - ios->nr_pages;
277 unsigned long len_less = pcol_src->length - ios->length;
278 unsigned i;
279 int ret;
281 /* This IO was trimmed */
282 pcol_src->nr_pages = ios->nr_pages;
283 pcol_src->length = ios->length;
285 /* Left over pages are passed to the next io */
286 pcol->expected_pages += pages_less;
287 pcol->nr_pages = pages_less;
288 pcol->length = len_less;
289 src_page = pcol_src->pages + pcol_src->nr_pages;
290 pcol->pg_first = (*src_page)->index;
292 ret = pcol_try_alloc(pcol);
293 if (unlikely(ret))
294 return ret;
296 for (i = 0; i < pages_less; ++i)
297 pcol->pages[i] = *src_page++;
299 EXOFS_DBGMSG("Length was adjusted nr_pages=0x%x "
300 "pages_less=0x%x expected_pages=0x%x "
301 "next_offset=0x%llx next_len=0x%lx\n",
302 pcol_src->nr_pages, pages_less, pcol->expected_pages,
303 pcol->pg_first * PAGE_SIZE, pcol->length);
305 return 0;
308 static int read_exec(struct page_collect *pcol)
310 struct exofs_i_info *oi = exofs_i(pcol->inode);
311 struct ore_io_state *ios;
312 struct page_collect *pcol_copy = NULL;
313 int ret;
315 if (!pcol->pages)
316 return 0;
318 if (!pcol->ios) {
319 int ret = ore_get_rw_state(&pcol->sbi->layout, &oi->oc, true,
320 pcol->pg_first << PAGE_CACHE_SHIFT,
321 pcol->length, &pcol->ios);
323 if (ret)
324 return ret;
327 ios = pcol->ios;
328 ios->pages = pcol->pages;
330 if (pcol->read_4_write) {
331 ore_read(pcol->ios);
332 return __readpages_done(pcol);
335 pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL);
336 if (!pcol_copy) {
337 ret = -ENOMEM;
338 goto err;
341 *pcol_copy = *pcol;
342 ios->done = readpages_done;
343 ios->private = pcol_copy;
345 /* pages ownership was passed to pcol_copy */
346 _pcol_reset(pcol);
348 ret = _maybe_not_all_in_one_io(ios, pcol_copy, pcol);
349 if (unlikely(ret))
350 goto err;
352 EXOFS_DBGMSG2("read_exec(0x%lx) offset=0x%llx length=0x%llx\n",
353 pcol->inode->i_ino, _LLU(ios->offset), _LLU(ios->length));
355 ret = ore_read(ios);
356 if (unlikely(ret))
357 goto err;
359 atomic_inc(&pcol->sbi->s_curr_pending);
361 return 0;
363 err:
364 if (!pcol_copy) /* Failed before ownership transfer */
365 pcol_copy = pcol;
366 _unlock_pcol_pages(pcol_copy, ret, READ);
367 pcol_free(pcol_copy);
368 kfree(pcol_copy);
370 return ret;
373 /* readpage_strip is called either directly from readpage() or by the VFS from
374 * within read_cache_pages(), to add one more page to be read. It will try to
375 * collect as many contiguous pages as posible. If a discontinuity is
376 * encountered, or it runs out of resources, it will submit the previous segment
377 * and will start a new collection. Eventually caller must submit the last
378 * segment if present.
380 static int readpage_strip(void *data, struct page *page)
382 struct page_collect *pcol = data;
383 struct inode *inode = pcol->inode;
384 struct exofs_i_info *oi = exofs_i(inode);
385 loff_t i_size = i_size_read(inode);
386 pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
387 size_t len;
388 int ret;
390 BUG_ON(!PageLocked(page));
392 /* FIXME: Just for debugging, will be removed */
393 if (PageUptodate(page))
394 EXOFS_ERR("PageUptodate(0x%lx, 0x%lx)\n", pcol->inode->i_ino,
395 page->index);
397 pcol->that_locked_page = page;
399 if (page->index < end_index)
400 len = PAGE_CACHE_SIZE;
401 else if (page->index == end_index)
402 len = i_size & ~PAGE_CACHE_MASK;
403 else
404 len = 0;
406 if (!len || !obj_created(oi)) {
407 /* this will be out of bounds, or doesn't exist yet.
408 * Current page is cleared and the request is split
410 clear_highpage(page);
412 SetPageUptodate(page);
413 if (PageError(page))
414 ClearPageError(page);
416 if (!pcol->read_4_write)
417 unlock_page(page);
418 EXOFS_DBGMSG("readpage_strip(0x%lx) empty page len=%zx "
419 "read_4_write=%d index=0x%lx end_index=0x%lx "
420 "splitting\n", inode->i_ino, len,
421 pcol->read_4_write, page->index, end_index);
423 return read_exec(pcol);
426 try_again:
428 if (unlikely(pcol->pg_first == -1)) {
429 pcol->pg_first = page->index;
430 } else if (unlikely((pcol->pg_first + pcol->nr_pages) !=
431 page->index)) {
432 /* Discontinuity detected, split the request */
433 ret = read_exec(pcol);
434 if (unlikely(ret))
435 goto fail;
436 goto try_again;
439 if (!pcol->pages) {
440 ret = pcol_try_alloc(pcol);
441 if (unlikely(ret))
442 goto fail;
445 if (len != PAGE_CACHE_SIZE)
446 zero_user(page, len, PAGE_CACHE_SIZE - len);
448 EXOFS_DBGMSG2(" readpage_strip(0x%lx, 0x%lx) len=0x%zx\n",
449 inode->i_ino, page->index, len);
451 ret = pcol_add_page(pcol, page, len);
452 if (ret) {
453 EXOFS_DBGMSG2("Failed pcol_add_page pages[i]=%p "
454 "this_len=0x%zx nr_pages=%u length=0x%lx\n",
455 page, len, pcol->nr_pages, pcol->length);
457 /* split the request, and start again with current page */
458 ret = read_exec(pcol);
459 if (unlikely(ret))
460 goto fail;
462 goto try_again;
465 return 0;
467 fail:
468 /* SetPageError(page); ??? */
469 unlock_page(page);
470 return ret;
473 static int exofs_readpages(struct file *file, struct address_space *mapping,
474 struct list_head *pages, unsigned nr_pages)
476 struct page_collect pcol;
477 int ret;
479 _pcol_init(&pcol, nr_pages, mapping->host);
481 ret = read_cache_pages(mapping, pages, readpage_strip, &pcol);
482 if (ret) {
483 EXOFS_ERR("read_cache_pages => %d\n", ret);
484 return ret;
487 ret = read_exec(&pcol);
488 if (unlikely(ret))
489 return ret;
491 return read_exec(&pcol);
494 static int _readpage(struct page *page, bool read_4_write)
496 struct page_collect pcol;
497 int ret;
499 _pcol_init(&pcol, 1, page->mapping->host);
501 pcol.read_4_write = read_4_write;
502 ret = readpage_strip(&pcol, page);
503 if (ret) {
504 EXOFS_ERR("_readpage => %d\n", ret);
505 return ret;
508 return read_exec(&pcol);
512 * We don't need the file
514 static int exofs_readpage(struct file *file, struct page *page)
516 return _readpage(page, false);
519 /* Callback for osd_write. All writes are asynchronous */
520 static void writepages_done(struct ore_io_state *ios, void *p)
522 struct page_collect *pcol = p;
523 int i;
524 u64 good_bytes;
525 u64 length = 0;
526 int ret = ore_check_io(ios, NULL);
528 atomic_dec(&pcol->sbi->s_curr_pending);
530 if (likely(!ret)) {
531 good_bytes = pcol->length;
532 ret = PAGE_WAS_NOT_IN_IO;
533 } else {
534 good_bytes = 0;
537 EXOFS_DBGMSG2("writepages_done(0x%lx) good_bytes=0x%llx"
538 " length=0x%lx nr_pages=%u\n",
539 pcol->inode->i_ino, _LLU(good_bytes), pcol->length,
540 pcol->nr_pages);
542 for (i = 0; i < pcol->nr_pages; i++) {
543 struct page *page = pcol->pages[i];
544 struct inode *inode = page->mapping->host;
545 int page_stat;
547 if (inode != pcol->inode)
548 continue; /* osd might add more pages to a bio */
550 if (likely(length < good_bytes))
551 page_stat = 0;
552 else
553 page_stat = ret;
555 update_write_page(page, page_stat);
556 unlock_page(page);
557 EXOFS_DBGMSG2(" writepages_done(0x%lx, 0x%lx) status=%d\n",
558 inode->i_ino, page->index, page_stat);
560 length += PAGE_SIZE;
563 pcol_free(pcol);
564 kfree(pcol);
565 EXOFS_DBGMSG2("writepages_done END\n");
568 static struct page *__r4w_get_page(void *priv, u64 offset, bool *uptodate)
570 struct page_collect *pcol = priv;
571 pgoff_t index = offset / PAGE_SIZE;
573 if (!pcol->that_locked_page ||
574 (pcol->that_locked_page->index != index)) {
575 struct page *page;
576 loff_t i_size = i_size_read(pcol->inode);
578 if (offset >= i_size) {
579 *uptodate = true;
580 EXOFS_DBGMSG("offset >= i_size index=0x%lx\n", index);
581 return ZERO_PAGE(0);
584 page = find_get_page(pcol->inode->i_mapping, index);
585 if (!page) {
586 page = find_or_create_page(pcol->inode->i_mapping,
587 index, GFP_NOFS);
588 if (unlikely(!page)) {
589 EXOFS_DBGMSG("grab_cache_page Failed "
590 "index=0x%llx\n", _LLU(index));
591 return NULL;
593 unlock_page(page);
595 if (PageDirty(page) || PageWriteback(page))
596 *uptodate = true;
597 else
598 *uptodate = PageUptodate(page);
599 EXOFS_DBGMSG("index=0x%lx uptodate=%d\n", index, *uptodate);
600 return page;
601 } else {
602 EXOFS_DBGMSG("YES that_locked_page index=0x%lx\n",
603 pcol->that_locked_page->index);
604 *uptodate = true;
605 return pcol->that_locked_page;
609 static void __r4w_put_page(void *priv, struct page *page)
611 struct page_collect *pcol = priv;
613 if ((pcol->that_locked_page != page) && (ZERO_PAGE(0) != page)) {
614 EXOFS_DBGMSG("index=0x%lx\n", page->index);
615 page_cache_release(page);
616 return;
618 EXOFS_DBGMSG("that_locked_page index=0x%lx\n",
619 ZERO_PAGE(0) == page ? -1 : page->index);
622 static const struct _ore_r4w_op _r4w_op = {
623 .get_page = &__r4w_get_page,
624 .put_page = &__r4w_put_page,
627 static int write_exec(struct page_collect *pcol)
629 struct exofs_i_info *oi = exofs_i(pcol->inode);
630 struct ore_io_state *ios;
631 struct page_collect *pcol_copy = NULL;
632 int ret;
634 if (!pcol->pages)
635 return 0;
637 BUG_ON(pcol->ios);
638 ret = ore_get_rw_state(&pcol->sbi->layout, &oi->oc, false,
639 pcol->pg_first << PAGE_CACHE_SHIFT,
640 pcol->length, &pcol->ios);
641 if (unlikely(ret))
642 goto err;
644 pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL);
645 if (!pcol_copy) {
646 EXOFS_ERR("write_exec: Failed to kmalloc(pcol)\n");
647 ret = -ENOMEM;
648 goto err;
651 *pcol_copy = *pcol;
653 ios = pcol->ios;
654 ios->pages = pcol_copy->pages;
655 ios->done = writepages_done;
656 ios->r4w = &_r4w_op;
657 ios->private = pcol_copy;
659 /* pages ownership was passed to pcol_copy */
660 _pcol_reset(pcol);
662 ret = _maybe_not_all_in_one_io(ios, pcol_copy, pcol);
663 if (unlikely(ret))
664 goto err;
666 EXOFS_DBGMSG2("write_exec(0x%lx) offset=0x%llx length=0x%llx\n",
667 pcol->inode->i_ino, _LLU(ios->offset), _LLU(ios->length));
669 ret = ore_write(ios);
670 if (unlikely(ret)) {
671 EXOFS_ERR("write_exec: ore_write() Failed\n");
672 goto err;
675 atomic_inc(&pcol->sbi->s_curr_pending);
676 return 0;
678 err:
679 if (!pcol_copy) /* Failed before ownership transfer */
680 pcol_copy = pcol;
681 _unlock_pcol_pages(pcol_copy, ret, WRITE);
682 pcol_free(pcol_copy);
683 kfree(pcol_copy);
685 return ret;
688 /* writepage_strip is called either directly from writepage() or by the VFS from
689 * within write_cache_pages(), to add one more page to be written to storage.
690 * It will try to collect as many contiguous pages as possible. If a
691 * discontinuity is encountered or it runs out of resources it will submit the
692 * previous segment and will start a new collection.
693 * Eventually caller must submit the last segment if present.
695 static int writepage_strip(struct page *page,
696 struct writeback_control *wbc_unused, void *data)
698 struct page_collect *pcol = data;
699 struct inode *inode = pcol->inode;
700 struct exofs_i_info *oi = exofs_i(inode);
701 loff_t i_size = i_size_read(inode);
702 pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
703 size_t len;
704 int ret;
706 BUG_ON(!PageLocked(page));
708 ret = wait_obj_created(oi);
709 if (unlikely(ret))
710 goto fail;
712 if (page->index < end_index)
713 /* in this case, the page is within the limits of the file */
714 len = PAGE_CACHE_SIZE;
715 else {
716 len = i_size & ~PAGE_CACHE_MASK;
718 if (page->index > end_index || !len) {
719 /* in this case, the page is outside the limits
720 * (truncate in progress)
722 ret = write_exec(pcol);
723 if (unlikely(ret))
724 goto fail;
725 if (PageError(page))
726 ClearPageError(page);
727 unlock_page(page);
728 EXOFS_DBGMSG("writepage_strip(0x%lx, 0x%lx) "
729 "outside the limits\n",
730 inode->i_ino, page->index);
731 return 0;
735 try_again:
737 if (unlikely(pcol->pg_first == -1)) {
738 pcol->pg_first = page->index;
739 } else if (unlikely((pcol->pg_first + pcol->nr_pages) !=
740 page->index)) {
741 /* Discontinuity detected, split the request */
742 ret = write_exec(pcol);
743 if (unlikely(ret))
744 goto fail;
746 EXOFS_DBGMSG("writepage_strip(0x%lx, 0x%lx) Discontinuity\n",
747 inode->i_ino, page->index);
748 goto try_again;
751 if (!pcol->pages) {
752 ret = pcol_try_alloc(pcol);
753 if (unlikely(ret))
754 goto fail;
757 EXOFS_DBGMSG2(" writepage_strip(0x%lx, 0x%lx) len=0x%zx\n",
758 inode->i_ino, page->index, len);
760 ret = pcol_add_page(pcol, page, len);
761 if (unlikely(ret)) {
762 EXOFS_DBGMSG2("Failed pcol_add_page "
763 "nr_pages=%u total_length=0x%lx\n",
764 pcol->nr_pages, pcol->length);
766 /* split the request, next loop will start again */
767 ret = write_exec(pcol);
768 if (unlikely(ret)) {
769 EXOFS_DBGMSG("write_exec failed => %d", ret);
770 goto fail;
773 goto try_again;
776 BUG_ON(PageWriteback(page));
777 set_page_writeback(page);
779 return 0;
781 fail:
782 EXOFS_DBGMSG("Error: writepage_strip(0x%lx, 0x%lx)=>%d\n",
783 inode->i_ino, page->index, ret);
784 set_bit(AS_EIO, &page->mapping->flags);
785 unlock_page(page);
786 return ret;
789 static int exofs_writepages(struct address_space *mapping,
790 struct writeback_control *wbc)
792 struct page_collect pcol;
793 long start, end, expected_pages;
794 int ret;
796 start = wbc->range_start >> PAGE_CACHE_SHIFT;
797 end = (wbc->range_end == LLONG_MAX) ?
798 start + mapping->nrpages :
799 wbc->range_end >> PAGE_CACHE_SHIFT;
801 if (start || end)
802 expected_pages = end - start + 1;
803 else
804 expected_pages = mapping->nrpages;
806 if (expected_pages < 32L)
807 expected_pages = 32L;
809 EXOFS_DBGMSG2("inode(0x%lx) wbc->start=0x%llx wbc->end=0x%llx "
810 "nrpages=%lu start=0x%lx end=0x%lx expected_pages=%ld\n",
811 mapping->host->i_ino, wbc->range_start, wbc->range_end,
812 mapping->nrpages, start, end, expected_pages);
814 _pcol_init(&pcol, expected_pages, mapping->host);
816 ret = write_cache_pages(mapping, wbc, writepage_strip, &pcol);
817 if (unlikely(ret)) {
818 EXOFS_ERR("write_cache_pages => %d\n", ret);
819 return ret;
822 ret = write_exec(&pcol);
823 if (unlikely(ret))
824 return ret;
826 if (wbc->sync_mode == WB_SYNC_ALL) {
827 return write_exec(&pcol); /* pump the last reminder */
828 } else if (pcol.nr_pages) {
829 /* not SYNC let the reminder join the next writeout */
830 unsigned i;
832 for (i = 0; i < pcol.nr_pages; i++) {
833 struct page *page = pcol.pages[i];
835 end_page_writeback(page);
836 set_page_dirty(page);
837 unlock_page(page);
840 return 0;
844 static int exofs_writepage(struct page *page, struct writeback_control *wbc)
846 struct page_collect pcol;
847 int ret;
849 _pcol_init(&pcol, 1, page->mapping->host);
851 ret = writepage_strip(page, NULL, &pcol);
852 if (ret) {
853 EXOFS_ERR("exofs_writepage => %d\n", ret);
854 return ret;
857 return write_exec(&pcol);
860 /* i_mutex held using inode->i_size directly */
861 static void _write_failed(struct inode *inode, loff_t to)
863 if (to > inode->i_size)
864 truncate_pagecache(inode, to, inode->i_size);
867 int exofs_write_begin(struct file *file, struct address_space *mapping,
868 loff_t pos, unsigned len, unsigned flags,
869 struct page **pagep, void **fsdata)
871 int ret = 0;
872 struct page *page;
874 page = *pagep;
875 if (page == NULL) {
876 ret = simple_write_begin(file, mapping, pos, len, flags, pagep,
877 fsdata);
878 if (ret) {
879 EXOFS_DBGMSG("simple_write_begin failed\n");
880 goto out;
883 page = *pagep;
886 /* read modify write */
887 if (!PageUptodate(page) && (len != PAGE_CACHE_SIZE)) {
888 loff_t i_size = i_size_read(mapping->host);
889 pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
890 size_t rlen;
892 if (page->index < end_index)
893 rlen = PAGE_CACHE_SIZE;
894 else if (page->index == end_index)
895 rlen = i_size & ~PAGE_CACHE_MASK;
896 else
897 rlen = 0;
899 if (!rlen) {
900 clear_highpage(page);
901 SetPageUptodate(page);
902 goto out;
905 ret = _readpage(page, true);
906 if (ret) {
907 /*SetPageError was done by _readpage. Is it ok?*/
908 unlock_page(page);
909 EXOFS_DBGMSG("__readpage failed\n");
912 out:
913 if (unlikely(ret))
914 _write_failed(mapping->host, pos + len);
916 return ret;
919 static int exofs_write_begin_export(struct file *file,
920 struct address_space *mapping,
921 loff_t pos, unsigned len, unsigned flags,
922 struct page **pagep, void **fsdata)
924 *pagep = NULL;
926 return exofs_write_begin(file, mapping, pos, len, flags, pagep,
927 fsdata);
930 static int exofs_write_end(struct file *file, struct address_space *mapping,
931 loff_t pos, unsigned len, unsigned copied,
932 struct page *page, void *fsdata)
934 struct inode *inode = mapping->host;
935 /* According to comment in simple_write_end i_mutex is held */
936 loff_t i_size = inode->i_size;
937 int ret;
939 ret = simple_write_end(file, mapping,pos, len, copied, page, fsdata);
940 if (unlikely(ret))
941 _write_failed(inode, pos + len);
943 /* TODO: once simple_write_end marks inode dirty remove */
944 if (i_size != inode->i_size)
945 mark_inode_dirty(inode);
946 return ret;
949 static int exofs_releasepage(struct page *page, gfp_t gfp)
951 EXOFS_DBGMSG("page 0x%lx\n", page->index);
952 WARN_ON(1);
953 return 0;
956 static void exofs_invalidatepage(struct page *page, unsigned long offset)
958 EXOFS_DBGMSG("page 0x%lx offset 0x%lx\n", page->index, offset);
959 WARN_ON(1);
962 const struct address_space_operations exofs_aops = {
963 .readpage = exofs_readpage,
964 .readpages = exofs_readpages,
965 .writepage = NULL,
966 .writepages = exofs_writepages,
967 .write_begin = exofs_write_begin_export,
968 .write_end = exofs_write_end,
969 .releasepage = exofs_releasepage,
970 .set_page_dirty = __set_page_dirty_nobuffers,
971 .invalidatepage = exofs_invalidatepage,
973 /* Not implemented Yet */
974 .bmap = NULL, /* TODO: use osd's OSD_ACT_READ_MAP */
975 .direct_IO = NULL, /* TODO: Should be trivial to do */
977 /* With these NULL has special meaning or default is not exported */
978 .get_xip_mem = NULL,
979 .migratepage = NULL,
980 .launder_page = NULL,
981 .is_partially_uptodate = NULL,
982 .error_remove_page = NULL,
985 /******************************************************************************
986 * INODE OPERATIONS
987 *****************************************************************************/
990 * Test whether an inode is a fast symlink.
992 static inline int exofs_inode_is_fast_symlink(struct inode *inode)
994 struct exofs_i_info *oi = exofs_i(inode);
996 return S_ISLNK(inode->i_mode) && (oi->i_data[0] != 0);
999 static int _do_truncate(struct inode *inode, loff_t newsize)
1001 struct exofs_i_info *oi = exofs_i(inode);
1002 struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
1003 int ret;
1005 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
1007 ret = ore_truncate(&sbi->layout, &oi->oc, (u64)newsize);
1008 if (likely(!ret))
1009 truncate_setsize(inode, newsize);
1011 EXOFS_DBGMSG("(0x%lx) size=0x%llx ret=>%d\n",
1012 inode->i_ino, newsize, ret);
1013 return ret;
1017 * Set inode attributes - update size attribute on OSD if needed,
1018 * otherwise just call generic functions.
1020 int exofs_setattr(struct dentry *dentry, struct iattr *iattr)
1022 struct inode *inode = dentry->d_inode;
1023 int error;
1025 /* if we are about to modify an object, and it hasn't been
1026 * created yet, wait
1028 error = wait_obj_created(exofs_i(inode));
1029 if (unlikely(error))
1030 return error;
1032 error = inode_change_ok(inode, iattr);
1033 if (unlikely(error))
1034 return error;
1036 if ((iattr->ia_valid & ATTR_SIZE) &&
1037 iattr->ia_size != i_size_read(inode)) {
1038 error = _do_truncate(inode, iattr->ia_size);
1039 if (unlikely(error))
1040 return error;
1043 setattr_copy(inode, iattr);
1044 mark_inode_dirty(inode);
1045 return 0;
1048 static const struct osd_attr g_attr_inode_file_layout = ATTR_DEF(
1049 EXOFS_APAGE_FS_DATA,
1050 EXOFS_ATTR_INODE_FILE_LAYOUT,
1052 static const struct osd_attr g_attr_inode_dir_layout = ATTR_DEF(
1053 EXOFS_APAGE_FS_DATA,
1054 EXOFS_ATTR_INODE_DIR_LAYOUT,
1058 * Read the Linux inode info from the OSD, and return it as is. In exofs the
1059 * inode info is in an application specific page/attribute of the osd-object.
1061 static int exofs_get_inode(struct super_block *sb, struct exofs_i_info *oi,
1062 struct exofs_fcb *inode)
1064 struct exofs_sb_info *sbi = sb->s_fs_info;
1065 struct osd_attr attrs[] = {
1066 [0] = g_attr_inode_data,
1067 [1] = g_attr_inode_file_layout,
1068 [2] = g_attr_inode_dir_layout,
1070 struct ore_io_state *ios;
1071 struct exofs_on_disk_inode_layout *layout;
1072 int ret;
1074 ret = ore_get_io_state(&sbi->layout, &oi->oc, &ios);
1075 if (unlikely(ret)) {
1076 EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
1077 return ret;
1080 attrs[1].len = exofs_on_disk_inode_layout_size(sbi->oc.numdevs);
1081 attrs[2].len = exofs_on_disk_inode_layout_size(sbi->oc.numdevs);
1083 ios->in_attr = attrs;
1084 ios->in_attr_len = ARRAY_SIZE(attrs);
1086 ret = ore_read(ios);
1087 if (unlikely(ret)) {
1088 EXOFS_ERR("object(0x%llx) corrupted, return empty file=>%d\n",
1089 _LLU(oi->one_comp.obj.id), ret);
1090 memset(inode, 0, sizeof(*inode));
1091 inode->i_mode = 0040000 | (0777 & ~022);
1092 /* If object is lost on target we might as well enable it's
1093 * delete.
1095 if ((ret == -ENOENT) || (ret == -EINVAL))
1096 ret = 0;
1097 goto out;
1100 ret = extract_attr_from_ios(ios, &attrs[0]);
1101 if (ret) {
1102 EXOFS_ERR("%s: extract_attr of inode_data failed\n", __func__);
1103 goto out;
1105 WARN_ON(attrs[0].len != EXOFS_INO_ATTR_SIZE);
1106 memcpy(inode, attrs[0].val_ptr, EXOFS_INO_ATTR_SIZE);
1108 ret = extract_attr_from_ios(ios, &attrs[1]);
1109 if (ret) {
1110 EXOFS_ERR("%s: extract_attr of inode_data failed\n", __func__);
1111 goto out;
1113 if (attrs[1].len) {
1114 layout = attrs[1].val_ptr;
1115 if (layout->gen_func != cpu_to_le16(LAYOUT_MOVING_WINDOW)) {
1116 EXOFS_ERR("%s: unsupported files layout %d\n",
1117 __func__, layout->gen_func);
1118 ret = -ENOTSUPP;
1119 goto out;
1123 ret = extract_attr_from_ios(ios, &attrs[2]);
1124 if (ret) {
1125 EXOFS_ERR("%s: extract_attr of inode_data failed\n", __func__);
1126 goto out;
1128 if (attrs[2].len) {
1129 layout = attrs[2].val_ptr;
1130 if (layout->gen_func != cpu_to_le16(LAYOUT_MOVING_WINDOW)) {
1131 EXOFS_ERR("%s: unsupported meta-data layout %d\n",
1132 __func__, layout->gen_func);
1133 ret = -ENOTSUPP;
1134 goto out;
1138 out:
1139 ore_put_io_state(ios);
1140 return ret;
1143 static void __oi_init(struct exofs_i_info *oi)
1145 init_waitqueue_head(&oi->i_wq);
1146 oi->i_flags = 0;
1149 * Fill in an inode read from the OSD and set it up for use
1151 struct inode *exofs_iget(struct super_block *sb, unsigned long ino)
1153 struct exofs_i_info *oi;
1154 struct exofs_fcb fcb;
1155 struct inode *inode;
1156 int ret;
1158 inode = iget_locked(sb, ino);
1159 if (!inode)
1160 return ERR_PTR(-ENOMEM);
1161 if (!(inode->i_state & I_NEW))
1162 return inode;
1163 oi = exofs_i(inode);
1164 __oi_init(oi);
1165 exofs_init_comps(&oi->oc, &oi->one_comp, sb->s_fs_info,
1166 exofs_oi_objno(oi));
1168 /* read the inode from the osd */
1169 ret = exofs_get_inode(sb, oi, &fcb);
1170 if (ret)
1171 goto bad_inode;
1173 set_obj_created(oi);
1175 /* copy stuff from on-disk struct to in-memory struct */
1176 inode->i_mode = le16_to_cpu(fcb.i_mode);
1177 i_uid_write(inode, le32_to_cpu(fcb.i_uid));
1178 i_gid_write(inode, le32_to_cpu(fcb.i_gid));
1179 set_nlink(inode, le16_to_cpu(fcb.i_links_count));
1180 inode->i_ctime.tv_sec = (signed)le32_to_cpu(fcb.i_ctime);
1181 inode->i_atime.tv_sec = (signed)le32_to_cpu(fcb.i_atime);
1182 inode->i_mtime.tv_sec = (signed)le32_to_cpu(fcb.i_mtime);
1183 inode->i_ctime.tv_nsec =
1184 inode->i_atime.tv_nsec = inode->i_mtime.tv_nsec = 0;
1185 oi->i_commit_size = le64_to_cpu(fcb.i_size);
1186 i_size_write(inode, oi->i_commit_size);
1187 inode->i_blkbits = EXOFS_BLKSHIFT;
1188 inode->i_generation = le32_to_cpu(fcb.i_generation);
1190 oi->i_dir_start_lookup = 0;
1192 if ((inode->i_nlink == 0) && (inode->i_mode == 0)) {
1193 ret = -ESTALE;
1194 goto bad_inode;
1197 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1198 if (fcb.i_data[0])
1199 inode->i_rdev =
1200 old_decode_dev(le32_to_cpu(fcb.i_data[0]));
1201 else
1202 inode->i_rdev =
1203 new_decode_dev(le32_to_cpu(fcb.i_data[1]));
1204 } else {
1205 memcpy(oi->i_data, fcb.i_data, sizeof(fcb.i_data));
1208 inode->i_mapping->backing_dev_info = sb->s_bdi;
1209 if (S_ISREG(inode->i_mode)) {
1210 inode->i_op = &exofs_file_inode_operations;
1211 inode->i_fop = &exofs_file_operations;
1212 inode->i_mapping->a_ops = &exofs_aops;
1213 } else if (S_ISDIR(inode->i_mode)) {
1214 inode->i_op = &exofs_dir_inode_operations;
1215 inode->i_fop = &exofs_dir_operations;
1216 inode->i_mapping->a_ops = &exofs_aops;
1217 } else if (S_ISLNK(inode->i_mode)) {
1218 if (exofs_inode_is_fast_symlink(inode))
1219 inode->i_op = &exofs_fast_symlink_inode_operations;
1220 else {
1221 inode->i_op = &exofs_symlink_inode_operations;
1222 inode->i_mapping->a_ops = &exofs_aops;
1224 } else {
1225 inode->i_op = &exofs_special_inode_operations;
1226 if (fcb.i_data[0])
1227 init_special_inode(inode, inode->i_mode,
1228 old_decode_dev(le32_to_cpu(fcb.i_data[0])));
1229 else
1230 init_special_inode(inode, inode->i_mode,
1231 new_decode_dev(le32_to_cpu(fcb.i_data[1])));
1234 unlock_new_inode(inode);
1235 return inode;
1237 bad_inode:
1238 iget_failed(inode);
1239 return ERR_PTR(ret);
1242 int __exofs_wait_obj_created(struct exofs_i_info *oi)
1244 if (!obj_created(oi)) {
1245 EXOFS_DBGMSG("!obj_created\n");
1246 BUG_ON(!obj_2bcreated(oi));
1247 wait_event(oi->i_wq, obj_created(oi));
1248 EXOFS_DBGMSG("wait_event done\n");
1250 return unlikely(is_bad_inode(&oi->vfs_inode)) ? -EIO : 0;
1254 * Callback function from exofs_new_inode(). The important thing is that we
1255 * set the obj_created flag so that other methods know that the object exists on
1256 * the OSD.
1258 static void create_done(struct ore_io_state *ios, void *p)
1260 struct inode *inode = p;
1261 struct exofs_i_info *oi = exofs_i(inode);
1262 struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
1263 int ret;
1265 ret = ore_check_io(ios, NULL);
1266 ore_put_io_state(ios);
1268 atomic_dec(&sbi->s_curr_pending);
1270 if (unlikely(ret)) {
1271 EXOFS_ERR("object=0x%llx creation failed in pid=0x%llx",
1272 _LLU(exofs_oi_objno(oi)),
1273 _LLU(oi->one_comp.obj.partition));
1274 /*TODO: When FS is corrupted creation can fail, object already
1275 * exist. Get rid of this asynchronous creation, if exist
1276 * increment the obj counter and try the next object. Until we
1277 * succeed. All these dangling objects will be made into lost
1278 * files by chkfs.exofs
1282 set_obj_created(oi);
1284 wake_up(&oi->i_wq);
1288 * Set up a new inode and create an object for it on the OSD
1290 struct inode *exofs_new_inode(struct inode *dir, umode_t mode)
1292 struct super_block *sb = dir->i_sb;
1293 struct exofs_sb_info *sbi = sb->s_fs_info;
1294 struct inode *inode;
1295 struct exofs_i_info *oi;
1296 struct ore_io_state *ios;
1297 int ret;
1299 inode = new_inode(sb);
1300 if (!inode)
1301 return ERR_PTR(-ENOMEM);
1303 oi = exofs_i(inode);
1304 __oi_init(oi);
1306 set_obj_2bcreated(oi);
1308 inode->i_mapping->backing_dev_info = sb->s_bdi;
1309 inode_init_owner(inode, dir, mode);
1310 inode->i_ino = sbi->s_nextid++;
1311 inode->i_blkbits = EXOFS_BLKSHIFT;
1312 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1313 oi->i_commit_size = inode->i_size = 0;
1314 spin_lock(&sbi->s_next_gen_lock);
1315 inode->i_generation = sbi->s_next_generation++;
1316 spin_unlock(&sbi->s_next_gen_lock);
1317 insert_inode_hash(inode);
1319 exofs_init_comps(&oi->oc, &oi->one_comp, sb->s_fs_info,
1320 exofs_oi_objno(oi));
1321 exofs_sbi_write_stats(sbi); /* Make sure new sbi->s_nextid is on disk */
1323 mark_inode_dirty(inode);
1325 ret = ore_get_io_state(&sbi->layout, &oi->oc, &ios);
1326 if (unlikely(ret)) {
1327 EXOFS_ERR("exofs_new_inode: ore_get_io_state failed\n");
1328 return ERR_PTR(ret);
1331 ios->done = create_done;
1332 ios->private = inode;
1334 ret = ore_create(ios);
1335 if (ret) {
1336 ore_put_io_state(ios);
1337 return ERR_PTR(ret);
1339 atomic_inc(&sbi->s_curr_pending);
1341 return inode;
1345 * struct to pass two arguments to update_inode's callback
1347 struct updatei_args {
1348 struct exofs_sb_info *sbi;
1349 struct exofs_fcb fcb;
1353 * Callback function from exofs_update_inode().
1355 static void updatei_done(struct ore_io_state *ios, void *p)
1357 struct updatei_args *args = p;
1359 ore_put_io_state(ios);
1361 atomic_dec(&args->sbi->s_curr_pending);
1363 kfree(args);
1367 * Write the inode to the OSD. Just fill up the struct, and set the attribute
1368 * synchronously or asynchronously depending on the do_sync flag.
1370 static int exofs_update_inode(struct inode *inode, int do_sync)
1372 struct exofs_i_info *oi = exofs_i(inode);
1373 struct super_block *sb = inode->i_sb;
1374 struct exofs_sb_info *sbi = sb->s_fs_info;
1375 struct ore_io_state *ios;
1376 struct osd_attr attr;
1377 struct exofs_fcb *fcb;
1378 struct updatei_args *args;
1379 int ret;
1381 args = kzalloc(sizeof(*args), GFP_KERNEL);
1382 if (!args) {
1383 EXOFS_DBGMSG("Failed kzalloc of args\n");
1384 return -ENOMEM;
1387 fcb = &args->fcb;
1389 fcb->i_mode = cpu_to_le16(inode->i_mode);
1390 fcb->i_uid = cpu_to_le32(i_uid_read(inode));
1391 fcb->i_gid = cpu_to_le32(i_gid_read(inode));
1392 fcb->i_links_count = cpu_to_le16(inode->i_nlink);
1393 fcb->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
1394 fcb->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
1395 fcb->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
1396 oi->i_commit_size = i_size_read(inode);
1397 fcb->i_size = cpu_to_le64(oi->i_commit_size);
1398 fcb->i_generation = cpu_to_le32(inode->i_generation);
1400 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1401 if (old_valid_dev(inode->i_rdev)) {
1402 fcb->i_data[0] =
1403 cpu_to_le32(old_encode_dev(inode->i_rdev));
1404 fcb->i_data[1] = 0;
1405 } else {
1406 fcb->i_data[0] = 0;
1407 fcb->i_data[1] =
1408 cpu_to_le32(new_encode_dev(inode->i_rdev));
1409 fcb->i_data[2] = 0;
1411 } else
1412 memcpy(fcb->i_data, oi->i_data, sizeof(fcb->i_data));
1414 ret = ore_get_io_state(&sbi->layout, &oi->oc, &ios);
1415 if (unlikely(ret)) {
1416 EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
1417 goto free_args;
1420 attr = g_attr_inode_data;
1421 attr.val_ptr = fcb;
1422 ios->out_attr_len = 1;
1423 ios->out_attr = &attr;
1425 wait_obj_created(oi);
1427 if (!do_sync) {
1428 args->sbi = sbi;
1429 ios->done = updatei_done;
1430 ios->private = args;
1433 ret = ore_write(ios);
1434 if (!do_sync && !ret) {
1435 atomic_inc(&sbi->s_curr_pending);
1436 goto out; /* deallocation in updatei_done */
1439 ore_put_io_state(ios);
1440 free_args:
1441 kfree(args);
1442 out:
1443 EXOFS_DBGMSG("(0x%lx) do_sync=%d ret=>%d\n",
1444 inode->i_ino, do_sync, ret);
1445 return ret;
1448 int exofs_write_inode(struct inode *inode, struct writeback_control *wbc)
1450 /* FIXME: fix fsync and use wbc->sync_mode == WB_SYNC_ALL */
1451 return exofs_update_inode(inode, 1);
1455 * Callback function from exofs_delete_inode() - don't have much cleaning up to
1456 * do.
1458 static void delete_done(struct ore_io_state *ios, void *p)
1460 struct exofs_sb_info *sbi = p;
1462 ore_put_io_state(ios);
1464 atomic_dec(&sbi->s_curr_pending);
1468 * Called when the refcount of an inode reaches zero. We remove the object
1469 * from the OSD here. We make sure the object was created before we try and
1470 * delete it.
1472 void exofs_evict_inode(struct inode *inode)
1474 struct exofs_i_info *oi = exofs_i(inode);
1475 struct super_block *sb = inode->i_sb;
1476 struct exofs_sb_info *sbi = sb->s_fs_info;
1477 struct ore_io_state *ios;
1478 int ret;
1480 truncate_inode_pages(&inode->i_data, 0);
1482 /* TODO: should do better here */
1483 if (inode->i_nlink || is_bad_inode(inode))
1484 goto no_delete;
1486 inode->i_size = 0;
1487 clear_inode(inode);
1489 /* if we are deleting an obj that hasn't been created yet, wait.
1490 * This also makes sure that create_done cannot be called with an
1491 * already evicted inode.
1493 wait_obj_created(oi);
1494 /* ignore the error, attempt a remove anyway */
1496 /* Now Remove the OSD objects */
1497 ret = ore_get_io_state(&sbi->layout, &oi->oc, &ios);
1498 if (unlikely(ret)) {
1499 EXOFS_ERR("%s: ore_get_io_state failed\n", __func__);
1500 return;
1503 ios->done = delete_done;
1504 ios->private = sbi;
1506 ret = ore_remove(ios);
1507 if (ret) {
1508 EXOFS_ERR("%s: ore_remove failed\n", __func__);
1509 ore_put_io_state(ios);
1510 return;
1512 atomic_inc(&sbi->s_curr_pending);
1514 return;
1516 no_delete:
1517 clear_inode(inode);