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authorSteven Whitehouse <swhiteho@redhat.com>2009-05-22 05:01:55 -0400
committerSteven Whitehouse <swhiteho@redhat.com>2009-05-22 05:01:55 -0400
commitb1e71b0622974953e46a284aa986504a90869a9b (patch)
tree0eb0f68c8b432b6332437e918ca2ab4e0c72d897 /fs/gfs2/aops.c
parent1ce97e564b628bee30b8dbb64e5e653a484308f6 (diff)
GFS2: Clean up some file names
This patch renames the ops_*.c files which have no counterpart without the ops_ prefix in order to shorten the name and make it more readable. In addition, ops_address.h (which was very small) is moved into inode.h and inode.h is cleaned up by adding extern where required. Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Diffstat (limited to 'fs/gfs2/aops.c')
-rw-r--r--fs/gfs2/aops.c1145
1 files changed, 1145 insertions, 0 deletions
diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c
new file mode 100644
index 000000000000..03ebb439ace0
--- /dev/null
+++ b/fs/gfs2/aops.c
@@ -0,0 +1,1145 @@
1/*
2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
4 *
5 * This copyrighted material is made available to anyone wishing to use,
6 * modify, copy, or redistribute it subject to the terms and conditions
7 * of the GNU General Public License version 2.
8 */
9
10#include <linux/sched.h>
11#include <linux/slab.h>
12#include <linux/spinlock.h>
13#include <linux/completion.h>
14#include <linux/buffer_head.h>
15#include <linux/pagemap.h>
16#include <linux/pagevec.h>
17#include <linux/mpage.h>
18#include <linux/fs.h>
19#include <linux/writeback.h>
20#include <linux/swap.h>
21#include <linux/gfs2_ondisk.h>
22#include <linux/backing-dev.h>
23
24#include "gfs2.h"
25#include "incore.h"
26#include "bmap.h"
27#include "glock.h"
28#include "inode.h"
29#include "log.h"
30#include "meta_io.h"
31#include "quota.h"
32#include "trans.h"
33#include "rgrp.h"
34#include "super.h"
35#include "util.h"
36#include "glops.h"
37
38
39static void gfs2_page_add_databufs(struct gfs2_inode *ip, struct page *page,
40 unsigned int from, unsigned int to)
41{
42 struct buffer_head *head = page_buffers(page);
43 unsigned int bsize = head->b_size;
44 struct buffer_head *bh;
45 unsigned int start, end;
46
47 for (bh = head, start = 0; bh != head || !start;
48 bh = bh->b_this_page, start = end) {
49 end = start + bsize;
50 if (end <= from || start >= to)
51 continue;
52 if (gfs2_is_jdata(ip))
53 set_buffer_uptodate(bh);
54 gfs2_trans_add_bh(ip->i_gl, bh, 0);
55 }
56}
57
58/**
59 * gfs2_get_block_noalloc - Fills in a buffer head with details about a block
60 * @inode: The inode
61 * @lblock: The block number to look up
62 * @bh_result: The buffer head to return the result in
63 * @create: Non-zero if we may add block to the file
64 *
65 * Returns: errno
66 */
67
68static int gfs2_get_block_noalloc(struct inode *inode, sector_t lblock,
69 struct buffer_head *bh_result, int create)
70{
71 int error;
72
73 error = gfs2_block_map(inode, lblock, bh_result, 0);
74 if (error)
75 return error;
76 if (!buffer_mapped(bh_result))
77 return -EIO;
78 return 0;
79}
80
81static int gfs2_get_block_direct(struct inode *inode, sector_t lblock,
82 struct buffer_head *bh_result, int create)
83{
84 return gfs2_block_map(inode, lblock, bh_result, 0);
85}
86
87/**
88 * gfs2_writepage_common - Common bits of writepage
89 * @page: The page to be written
90 * @wbc: The writeback control
91 *
92 * Returns: 1 if writepage is ok, otherwise an error code or zero if no error.
93 */
94
95static int gfs2_writepage_common(struct page *page,
96 struct writeback_control *wbc)
97{
98 struct inode *inode = page->mapping->host;
99 struct gfs2_inode *ip = GFS2_I(inode);
100 struct gfs2_sbd *sdp = GFS2_SB(inode);
101 loff_t i_size = i_size_read(inode);
102 pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
103 unsigned offset;
104
105 if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(ip->i_gl)))
106 goto out;
107 if (current->journal_info)
108 goto redirty;
109 /* Is the page fully outside i_size? (truncate in progress) */
110 offset = i_size & (PAGE_CACHE_SIZE-1);
111 if (page->index > end_index || (page->index == end_index && !offset)) {
112 page->mapping->a_ops->invalidatepage(page, 0);
113 goto out;
114 }
115 return 1;
116redirty:
117 redirty_page_for_writepage(wbc, page);
118out:
119 unlock_page(page);
120 return 0;
121}
122
123/**
124 * gfs2_writeback_writepage - Write page for writeback mappings
125 * @page: The page
126 * @wbc: The writeback control
127 *
128 */
129
130static int gfs2_writeback_writepage(struct page *page,
131 struct writeback_control *wbc)
132{
133 int ret;
134
135 ret = gfs2_writepage_common(page, wbc);
136 if (ret <= 0)
137 return ret;
138
139 ret = mpage_writepage(page, gfs2_get_block_noalloc, wbc);
140 if (ret == -EAGAIN)
141 ret = block_write_full_page(page, gfs2_get_block_noalloc, wbc);
142 return ret;
143}
144
145/**
146 * gfs2_ordered_writepage - Write page for ordered data files
147 * @page: The page to write
148 * @wbc: The writeback control
149 *
150 */
151
152static int gfs2_ordered_writepage(struct page *page,
153 struct writeback_control *wbc)
154{
155 struct inode *inode = page->mapping->host;
156 struct gfs2_inode *ip = GFS2_I(inode);
157 int ret;
158
159 ret = gfs2_writepage_common(page, wbc);
160 if (ret <= 0)
161 return ret;
162
163 if (!page_has_buffers(page)) {
164 create_empty_buffers(page, inode->i_sb->s_blocksize,
165 (1 << BH_Dirty)|(1 << BH_Uptodate));
166 }
167 gfs2_page_add_databufs(ip, page, 0, inode->i_sb->s_blocksize-1);
168 return block_write_full_page(page, gfs2_get_block_noalloc, wbc);
169}
170
171/**
172 * __gfs2_jdata_writepage - The core of jdata writepage
173 * @page: The page to write
174 * @wbc: The writeback control
175 *
176 * This is shared between writepage and writepages and implements the
177 * core of the writepage operation. If a transaction is required then
178 * PageChecked will have been set and the transaction will have
179 * already been started before this is called.
180 */
181
182static int __gfs2_jdata_writepage(struct page *page, struct writeback_control *wbc)
183{
184 struct inode *inode = page->mapping->host;
185 struct gfs2_inode *ip = GFS2_I(inode);
186 struct gfs2_sbd *sdp = GFS2_SB(inode);
187
188 if (PageChecked(page)) {
189 ClearPageChecked(page);
190 if (!page_has_buffers(page)) {
191 create_empty_buffers(page, inode->i_sb->s_blocksize,
192 (1 << BH_Dirty)|(1 << BH_Uptodate));
193 }
194 gfs2_page_add_databufs(ip, page, 0, sdp->sd_vfs->s_blocksize-1);
195 }
196 return block_write_full_page(page, gfs2_get_block_noalloc, wbc);
197}
198
199/**
200 * gfs2_jdata_writepage - Write complete page
201 * @page: Page to write
202 *
203 * Returns: errno
204 *
205 */
206
207static int gfs2_jdata_writepage(struct page *page, struct writeback_control *wbc)
208{
209 struct inode *inode = page->mapping->host;
210 struct gfs2_sbd *sdp = GFS2_SB(inode);
211 int ret;
212 int done_trans = 0;
213
214 if (PageChecked(page)) {
215 if (wbc->sync_mode != WB_SYNC_ALL)
216 goto out_ignore;
217 ret = gfs2_trans_begin(sdp, RES_DINODE + 1, 0);
218 if (ret)
219 goto out_ignore;
220 done_trans = 1;
221 }
222 ret = gfs2_writepage_common(page, wbc);
223 if (ret > 0)
224 ret = __gfs2_jdata_writepage(page, wbc);
225 if (done_trans)
226 gfs2_trans_end(sdp);
227 return ret;
228
229out_ignore:
230 redirty_page_for_writepage(wbc, page);
231 unlock_page(page);
232 return 0;
233}
234
235/**
236 * gfs2_writeback_writepages - Write a bunch of dirty pages back to disk
237 * @mapping: The mapping to write
238 * @wbc: Write-back control
239 *
240 * For the data=writeback case we can already ignore buffer heads
241 * and write whole extents at once. This is a big reduction in the
242 * number of I/O requests we send and the bmap calls we make in this case.
243 */
244static int gfs2_writeback_writepages(struct address_space *mapping,
245 struct writeback_control *wbc)
246{
247 return mpage_writepages(mapping, wbc, gfs2_get_block_noalloc);
248}
249
250/**
251 * gfs2_write_jdata_pagevec - Write back a pagevec's worth of pages
252 * @mapping: The mapping
253 * @wbc: The writeback control
254 * @writepage: The writepage function to call for each page
255 * @pvec: The vector of pages
256 * @nr_pages: The number of pages to write
257 *
258 * Returns: non-zero if loop should terminate, zero otherwise
259 */
260
261static int gfs2_write_jdata_pagevec(struct address_space *mapping,
262 struct writeback_control *wbc,
263 struct pagevec *pvec,
264 int nr_pages, pgoff_t end)
265{
266 struct inode *inode = mapping->host;
267 struct gfs2_sbd *sdp = GFS2_SB(inode);
268 loff_t i_size = i_size_read(inode);
269 pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
270 unsigned offset = i_size & (PAGE_CACHE_SIZE-1);
271 unsigned nrblocks = nr_pages * (PAGE_CACHE_SIZE/inode->i_sb->s_blocksize);
272 struct backing_dev_info *bdi = mapping->backing_dev_info;
273 int i;
274 int ret;
275
276 ret = gfs2_trans_begin(sdp, nrblocks, nrblocks);
277 if (ret < 0)
278 return ret;
279
280 for(i = 0; i < nr_pages; i++) {
281 struct page *page = pvec->pages[i];
282
283 lock_page(page);
284
285 if (unlikely(page->mapping != mapping)) {
286 unlock_page(page);
287 continue;
288 }
289
290 if (!wbc->range_cyclic && page->index > end) {
291 ret = 1;
292 unlock_page(page);
293 continue;
294 }
295
296 if (wbc->sync_mode != WB_SYNC_NONE)
297 wait_on_page_writeback(page);
298
299 if (PageWriteback(page) ||
300 !clear_page_dirty_for_io(page)) {
301 unlock_page(page);
302 continue;
303 }
304
305 /* Is the page fully outside i_size? (truncate in progress) */
306 if (page->index > end_index || (page->index == end_index && !offset)) {
307 page->mapping->a_ops->invalidatepage(page, 0);
308 unlock_page(page);
309 continue;
310 }
311
312 ret = __gfs2_jdata_writepage(page, wbc);
313
314 if (ret || (--(wbc->nr_to_write) <= 0))
315 ret = 1;
316 if (wbc->nonblocking && bdi_write_congested(bdi)) {
317 wbc->encountered_congestion = 1;
318 ret = 1;
319 }
320
321 }
322 gfs2_trans_end(sdp);
323 return ret;
324}
325
326/**
327 * gfs2_write_cache_jdata - Like write_cache_pages but different
328 * @mapping: The mapping to write
329 * @wbc: The writeback control
330 * @writepage: The writepage function to call
331 * @data: The data to pass to writepage
332 *
333 * The reason that we use our own function here is that we need to
334 * start transactions before we grab page locks. This allows us
335 * to get the ordering right.
336 */
337
338static int gfs2_write_cache_jdata(struct address_space *mapping,
339 struct writeback_control *wbc)
340{
341 struct backing_dev_info *bdi = mapping->backing_dev_info;
342 int ret = 0;
343 int done = 0;
344 struct pagevec pvec;
345 int nr_pages;
346 pgoff_t index;
347 pgoff_t end;
348 int scanned = 0;
349 int range_whole = 0;
350
351 if (wbc->nonblocking && bdi_write_congested(bdi)) {
352 wbc->encountered_congestion = 1;
353 return 0;
354 }
355
356 pagevec_init(&pvec, 0);
357 if (wbc->range_cyclic) {
358 index = mapping->writeback_index; /* Start from prev offset */
359 end = -1;
360 } else {
361 index = wbc->range_start >> PAGE_CACHE_SHIFT;
362 end = wbc->range_end >> PAGE_CACHE_SHIFT;
363 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
364 range_whole = 1;
365 scanned = 1;
366 }
367
368retry:
369 while (!done && (index <= end) &&
370 (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
371 PAGECACHE_TAG_DIRTY,
372 min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1))) {
373 scanned = 1;
374 ret = gfs2_write_jdata_pagevec(mapping, wbc, &pvec, nr_pages, end);
375 if (ret)
376 done = 1;
377 if (ret > 0)
378 ret = 0;
379
380 pagevec_release(&pvec);
381 cond_resched();
382 }
383
384 if (!scanned && !done) {
385 /*
386 * We hit the last page and there is more work to be done: wrap
387 * back to the start of the file
388 */
389 scanned = 1;
390 index = 0;
391 goto retry;
392 }
393
394 if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
395 mapping->writeback_index = index;
396 return ret;
397}
398
399
400/**
401 * gfs2_jdata_writepages - Write a bunch of dirty pages back to disk
402 * @mapping: The mapping to write
403 * @wbc: The writeback control
404 *
405 */
406
407static int gfs2_jdata_writepages(struct address_space *mapping,
408 struct writeback_control *wbc)
409{
410 struct gfs2_inode *ip = GFS2_I(mapping->host);
411 struct gfs2_sbd *sdp = GFS2_SB(mapping->host);
412 int ret;
413
414 ret = gfs2_write_cache_jdata(mapping, wbc);
415 if (ret == 0 && wbc->sync_mode == WB_SYNC_ALL) {
416 gfs2_log_flush(sdp, ip->i_gl);
417 ret = gfs2_write_cache_jdata(mapping, wbc);
418 }
419 return ret;
420}
421
422/**
423 * stuffed_readpage - Fill in a Linux page with stuffed file data
424 * @ip: the inode
425 * @page: the page
426 *
427 * Returns: errno
428 */
429
430static int stuffed_readpage(struct gfs2_inode *ip, struct page *page)
431{
432 struct buffer_head *dibh;
433 void *kaddr;
434 int error;
435
436 /*
437 * Due to the order of unstuffing files and ->fault(), we can be
438 * asked for a zero page in the case of a stuffed file being extended,
439 * so we need to supply one here. It doesn't happen often.
440 */
441 if (unlikely(page->index)) {
442 zero_user(page, 0, PAGE_CACHE_SIZE);
443 SetPageUptodate(page);
444 return 0;
445 }
446
447 error = gfs2_meta_inode_buffer(ip, &dibh);
448 if (error)
449 return error;
450
451 kaddr = kmap_atomic(page, KM_USER0);
452 memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode),
453 ip->i_disksize);
454 memset(kaddr + ip->i_disksize, 0, PAGE_CACHE_SIZE - ip->i_disksize);
455 kunmap_atomic(kaddr, KM_USER0);
456 flush_dcache_page(page);
457 brelse(dibh);
458 SetPageUptodate(page);
459
460 return 0;
461}
462
463
464/**
465 * __gfs2_readpage - readpage
466 * @file: The file to read a page for
467 * @page: The page to read
468 *
469 * This is the core of gfs2's readpage. Its used by the internal file
470 * reading code as in that case we already hold the glock. Also its
471 * called by gfs2_readpage() once the required lock has been granted.
472 *
473 */
474
475static int __gfs2_readpage(void *file, struct page *page)
476{
477 struct gfs2_inode *ip = GFS2_I(page->mapping->host);
478 struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
479 int error;
480
481 if (gfs2_is_stuffed(ip)) {
482 error = stuffed_readpage(ip, page);
483 unlock_page(page);
484 } else {
485 error = mpage_readpage(page, gfs2_block_map);
486 }
487
488 if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
489 return -EIO;
490
491 return error;
492}
493
494/**
495 * gfs2_readpage - read a page of a file
496 * @file: The file to read
497 * @page: The page of the file
498 *
499 * This deals with the locking required. We have to unlock and
500 * relock the page in order to get the locking in the right
501 * order.
502 */
503
504static int gfs2_readpage(struct file *file, struct page *page)
505{
506 struct address_space *mapping = page->mapping;
507 struct gfs2_inode *ip = GFS2_I(mapping->host);
508 struct gfs2_holder gh;
509 int error;
510
511 unlock_page(page);
512 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
513 error = gfs2_glock_nq(&gh);
514 if (unlikely(error))
515 goto out;
516 error = AOP_TRUNCATED_PAGE;
517 lock_page(page);
518 if (page->mapping == mapping && !PageUptodate(page))
519 error = __gfs2_readpage(file, page);
520 else
521 unlock_page(page);
522 gfs2_glock_dq(&gh);
523out:
524 gfs2_holder_uninit(&gh);
525 if (error && error != AOP_TRUNCATED_PAGE)
526 lock_page(page);
527 return error;
528}
529
530/**
531 * gfs2_internal_read - read an internal file
532 * @ip: The gfs2 inode
533 * @ra_state: The readahead state (or NULL for no readahead)
534 * @buf: The buffer to fill
535 * @pos: The file position
536 * @size: The amount to read
537 *
538 */
539
540int gfs2_internal_read(struct gfs2_inode *ip, struct file_ra_state *ra_state,
541 char *buf, loff_t *pos, unsigned size)
542{
543 struct address_space *mapping = ip->i_inode.i_mapping;
544 unsigned long index = *pos / PAGE_CACHE_SIZE;
545 unsigned offset = *pos & (PAGE_CACHE_SIZE - 1);
546 unsigned copied = 0;
547 unsigned amt;
548 struct page *page;
549 void *p;
550
551 do {
552 amt = size - copied;
553 if (offset + size > PAGE_CACHE_SIZE)
554 amt = PAGE_CACHE_SIZE - offset;
555 page = read_cache_page(mapping, index, __gfs2_readpage, NULL);
556 if (IS_ERR(page))
557 return PTR_ERR(page);
558 p = kmap_atomic(page, KM_USER0);
559 memcpy(buf + copied, p + offset, amt);
560 kunmap_atomic(p, KM_USER0);
561 mark_page_accessed(page);
562 page_cache_release(page);
563 copied += amt;
564 index++;
565 offset = 0;
566 } while(copied < size);
567 (*pos) += size;
568 return size;
569}
570
571/**
572 * gfs2_readpages - Read a bunch of pages at once
573 *
574 * Some notes:
575 * 1. This is only for readahead, so we can simply ignore any things
576 * which are slightly inconvenient (such as locking conflicts between
577 * the page lock and the glock) and return having done no I/O. Its
578 * obviously not something we'd want to do on too regular a basis.
579 * Any I/O we ignore at this time will be done via readpage later.
580 * 2. We don't handle stuffed files here we let readpage do the honours.
581 * 3. mpage_readpages() does most of the heavy lifting in the common case.
582 * 4. gfs2_block_map() is relied upon to set BH_Boundary in the right places.
583 */
584
585static int gfs2_readpages(struct file *file, struct address_space *mapping,
586 struct list_head *pages, unsigned nr_pages)
587{
588 struct inode *inode = mapping->host;
589 struct gfs2_inode *ip = GFS2_I(inode);
590 struct gfs2_sbd *sdp = GFS2_SB(inode);
591 struct gfs2_holder gh;
592 int ret;
593
594 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
595 ret = gfs2_glock_nq(&gh);
596 if (unlikely(ret))
597 goto out_uninit;
598 if (!gfs2_is_stuffed(ip))
599 ret = mpage_readpages(mapping, pages, nr_pages, gfs2_block_map);
600 gfs2_glock_dq(&gh);
601out_uninit:
602 gfs2_holder_uninit(&gh);
603 if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
604 ret = -EIO;
605 return ret;
606}
607
608/**
609 * gfs2_write_begin - Begin to write to a file
610 * @file: The file to write to
611 * @mapping: The mapping in which to write
612 * @pos: The file offset at which to start writing
613 * @len: Length of the write
614 * @flags: Various flags
615 * @pagep: Pointer to return the page
616 * @fsdata: Pointer to return fs data (unused by GFS2)
617 *
618 * Returns: errno
619 */
620
621static int gfs2_write_begin(struct file *file, struct address_space *mapping,
622 loff_t pos, unsigned len, unsigned flags,
623 struct page **pagep, void **fsdata)
624{
625 struct gfs2_inode *ip = GFS2_I(mapping->host);
626 struct gfs2_sbd *sdp = GFS2_SB(mapping->host);
627 unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
628 int alloc_required;
629 int error = 0;
630 struct gfs2_alloc *al;
631 pgoff_t index = pos >> PAGE_CACHE_SHIFT;
632 unsigned from = pos & (PAGE_CACHE_SIZE - 1);
633 unsigned to = from + len;
634 struct page *page;
635
636 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &ip->i_gh);
637 error = gfs2_glock_nq(&ip->i_gh);
638 if (unlikely(error))
639 goto out_uninit;
640
641 error = gfs2_write_alloc_required(ip, pos, len, &alloc_required);
642 if (error)
643 goto out_unlock;
644
645 if (alloc_required || gfs2_is_jdata(ip))
646 gfs2_write_calc_reserv(ip, len, &data_blocks, &ind_blocks);
647
648 if (alloc_required) {
649 al = gfs2_alloc_get(ip);
650 if (!al) {
651 error = -ENOMEM;
652 goto out_unlock;
653 }
654
655 error = gfs2_quota_lock_check(ip);
656 if (error)
657 goto out_alloc_put;
658
659 al->al_requested = data_blocks + ind_blocks;
660 error = gfs2_inplace_reserve(ip);
661 if (error)
662 goto out_qunlock;
663 }
664
665 rblocks = RES_DINODE + ind_blocks;
666 if (gfs2_is_jdata(ip))
667 rblocks += data_blocks ? data_blocks : 1;
668 if (ind_blocks || data_blocks)
669 rblocks += RES_STATFS + RES_QUOTA;
670
671 error = gfs2_trans_begin(sdp, rblocks,
672 PAGE_CACHE_SIZE/sdp->sd_sb.sb_bsize);
673 if (error)
674 goto out_trans_fail;
675
676 error = -ENOMEM;
677 flags |= AOP_FLAG_NOFS;
678 page = grab_cache_page_write_begin(mapping, index, flags);
679 *pagep = page;
680 if (unlikely(!page))
681 goto out_endtrans;
682
683 if (gfs2_is_stuffed(ip)) {
684 error = 0;
685 if (pos + len > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) {
686 error = gfs2_unstuff_dinode(ip, page);
687 if (error == 0)
688 goto prepare_write;
689 } else if (!PageUptodate(page)) {
690 error = stuffed_readpage(ip, page);
691 }
692 goto out;
693 }
694
695prepare_write:
696 error = block_prepare_write(page, from, to, gfs2_block_map);
697out:
698 if (error == 0)
699 return 0;
700
701 page_cache_release(page);
702 if (pos + len > ip->i_inode.i_size)
703 vmtruncate(&ip->i_inode, ip->i_inode.i_size);
704out_endtrans:
705 gfs2_trans_end(sdp);
706out_trans_fail:
707 if (alloc_required) {
708 gfs2_inplace_release(ip);
709out_qunlock:
710 gfs2_quota_unlock(ip);
711out_alloc_put:
712 gfs2_alloc_put(ip);
713 }
714out_unlock:
715 gfs2_glock_dq(&ip->i_gh);
716out_uninit:
717 gfs2_holder_uninit(&ip->i_gh);
718 return error;
719}
720
721/**
722 * adjust_fs_space - Adjusts the free space available due to gfs2_grow
723 * @inode: the rindex inode
724 */
725static void adjust_fs_space(struct inode *inode)
726{
727 struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
728 struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
729 struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
730 u64 fs_total, new_free;
731
732 /* Total up the file system space, according to the latest rindex. */
733 fs_total = gfs2_ri_total(sdp);
734
735 spin_lock(&sdp->sd_statfs_spin);
736 if (fs_total > (m_sc->sc_total + l_sc->sc_total))
737 new_free = fs_total - (m_sc->sc_total + l_sc->sc_total);
738 else
739 new_free = 0;
740 spin_unlock(&sdp->sd_statfs_spin);
741 fs_warn(sdp, "File system extended by %llu blocks.\n",
742 (unsigned long long)new_free);
743 gfs2_statfs_change(sdp, new_free, new_free, 0);
744}
745
746/**
747 * gfs2_stuffed_write_end - Write end for stuffed files
748 * @inode: The inode
749 * @dibh: The buffer_head containing the on-disk inode
750 * @pos: The file position
751 * @len: The length of the write
752 * @copied: How much was actually copied by the VFS
753 * @page: The page
754 *
755 * This copies the data from the page into the inode block after
756 * the inode data structure itself.
757 *
758 * Returns: errno
759 */
760static int gfs2_stuffed_write_end(struct inode *inode, struct buffer_head *dibh,
761 loff_t pos, unsigned len, unsigned copied,
762 struct page *page)
763{
764 struct gfs2_inode *ip = GFS2_I(inode);
765 struct gfs2_sbd *sdp = GFS2_SB(inode);
766 u64 to = pos + copied;
767 void *kaddr;
768 unsigned char *buf = dibh->b_data + sizeof(struct gfs2_dinode);
769 struct gfs2_dinode *di = (struct gfs2_dinode *)dibh->b_data;
770
771 BUG_ON((pos + len) > (dibh->b_size - sizeof(struct gfs2_dinode)));
772 kaddr = kmap_atomic(page, KM_USER0);
773 memcpy(buf + pos, kaddr + pos, copied);
774 memset(kaddr + pos + copied, 0, len - copied);
775 flush_dcache_page(page);
776 kunmap_atomic(kaddr, KM_USER0);
777
778 if (!PageUptodate(page))
779 SetPageUptodate(page);
780 unlock_page(page);
781 page_cache_release(page);
782
783 if (copied) {
784 if (inode->i_size < to) {
785 i_size_write(inode, to);
786 ip->i_disksize = inode->i_size;
787 }
788 gfs2_dinode_out(ip, di);
789 mark_inode_dirty(inode);
790 }
791
792 if (inode == sdp->sd_rindex)
793 adjust_fs_space(inode);
794
795 brelse(dibh);
796 gfs2_trans_end(sdp);
797 gfs2_glock_dq(&ip->i_gh);
798 gfs2_holder_uninit(&ip->i_gh);
799 return copied;
800}
801
802/**
803 * gfs2_write_end
804 * @file: The file to write to
805 * @mapping: The address space to write to
806 * @pos: The file position
807 * @len: The length of the data
808 * @copied:
809 * @page: The page that has been written
810 * @fsdata: The fsdata (unused in GFS2)
811 *
812 * The main write_end function for GFS2. We have a separate one for
813 * stuffed files as they are slightly different, otherwise we just
814 * put our locking around the VFS provided functions.
815 *
816 * Returns: errno
817 */
818
819static int gfs2_write_end(struct file *file, struct address_space *mapping,
820 loff_t pos, unsigned len, unsigned copied,
821 struct page *page, void *fsdata)
822{
823 struct inode *inode = page->mapping->host;
824 struct gfs2_inode *ip = GFS2_I(inode);
825 struct gfs2_sbd *sdp = GFS2_SB(inode);
826 struct buffer_head *dibh;
827 struct gfs2_alloc *al = ip->i_alloc;
828 unsigned int from = pos & (PAGE_CACHE_SIZE - 1);
829 unsigned int to = from + len;
830 int ret;
831
832 BUG_ON(gfs2_glock_is_locked_by_me(ip->i_gl) == NULL);
833
834 ret = gfs2_meta_inode_buffer(ip, &dibh);
835 if (unlikely(ret)) {
836 unlock_page(page);
837 page_cache_release(page);
838 goto failed;
839 }
840
841 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
842
843 if (gfs2_is_stuffed(ip))
844 return gfs2_stuffed_write_end(inode, dibh, pos, len, copied, page);
845
846 if (!gfs2_is_writeback(ip))
847 gfs2_page_add_databufs(ip, page, from, to);
848
849 ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata);
850 if (ret > 0) {
851 if (inode->i_size > ip->i_disksize)
852 ip->i_disksize = inode->i_size;
853 gfs2_dinode_out(ip, dibh->b_data);
854 mark_inode_dirty(inode);
855 }
856
857 if (inode == sdp->sd_rindex)
858 adjust_fs_space(inode);
859
860 brelse(dibh);
861 gfs2_trans_end(sdp);
862failed:
863 if (al) {
864 gfs2_inplace_release(ip);
865 gfs2_quota_unlock(ip);
866 gfs2_alloc_put(ip);
867 }
868 gfs2_glock_dq(&ip->i_gh);
869 gfs2_holder_uninit(&ip->i_gh);
870 return ret;
871}
872
873/**
874 * gfs2_set_page_dirty - Page dirtying function
875 * @page: The page to dirty
876 *
877 * Returns: 1 if it dirtyed the page, or 0 otherwise
878 */
879
880static int gfs2_set_page_dirty(struct page *page)
881{
882 SetPageChecked(page);
883 return __set_page_dirty_buffers(page);
884}
885
886/**
887 * gfs2_bmap - Block map function
888 * @mapping: Address space info
889 * @lblock: The block to map
890 *
891 * Returns: The disk address for the block or 0 on hole or error
892 */
893
894static sector_t gfs2_bmap(struct address_space *mapping, sector_t lblock)
895{
896 struct gfs2_inode *ip = GFS2_I(mapping->host);
897 struct gfs2_holder i_gh;
898 sector_t dblock = 0;
899 int error;
900
901 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
902 if (error)
903 return 0;
904
905 if (!gfs2_is_stuffed(ip))
906 dblock = generic_block_bmap(mapping, lblock, gfs2_block_map);
907
908 gfs2_glock_dq_uninit(&i_gh);
909
910 return dblock;
911}
912
913static void gfs2_discard(struct gfs2_sbd *sdp, struct buffer_head *bh)
914{
915 struct gfs2_bufdata *bd;
916
917 lock_buffer(bh);
918 gfs2_log_lock(sdp);
919 clear_buffer_dirty(bh);
920 bd = bh->b_private;
921 if (bd) {
922 if (!list_empty(&bd->bd_le.le_list) && !buffer_pinned(bh))
923 list_del_init(&bd->bd_le.le_list);
924 else
925 gfs2_remove_from_journal(bh, current->journal_info, 0);
926 }
927 bh->b_bdev = NULL;
928 clear_buffer_mapped(bh);
929 clear_buffer_req(bh);
930 clear_buffer_new(bh);
931 gfs2_log_unlock(sdp);
932 unlock_buffer(bh);
933}
934
935static void gfs2_invalidatepage(struct page *page, unsigned long offset)
936{
937 struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
938 struct buffer_head *bh, *head;
939 unsigned long pos = 0;
940
941 BUG_ON(!PageLocked(page));
942 if (offset == 0)
943 ClearPageChecked(page);
944 if (!page_has_buffers(page))
945 goto out;
946
947 bh = head = page_buffers(page);
948 do {
949 if (offset <= pos)
950 gfs2_discard(sdp, bh);
951 pos += bh->b_size;
952 bh = bh->b_this_page;
953 } while (bh != head);
954out:
955 if (offset == 0)
956 try_to_release_page(page, 0);
957}
958
959/**
960 * gfs2_ok_for_dio - check that dio is valid on this file
961 * @ip: The inode
962 * @rw: READ or WRITE
963 * @offset: The offset at which we are reading or writing
964 *
965 * Returns: 0 (to ignore the i/o request and thus fall back to buffered i/o)
966 * 1 (to accept the i/o request)
967 */
968static int gfs2_ok_for_dio(struct gfs2_inode *ip, int rw, loff_t offset)
969{
970 /*
971 * Should we return an error here? I can't see that O_DIRECT for
972 * a stuffed file makes any sense. For now we'll silently fall
973 * back to buffered I/O
974 */
975 if (gfs2_is_stuffed(ip))
976 return 0;
977
978 if (offset >= i_size_read(&ip->i_inode))
979 return 0;
980 return 1;
981}
982
983
984
985static ssize_t gfs2_direct_IO(int rw, struct kiocb *iocb,
986 const struct iovec *iov, loff_t offset,
987 unsigned long nr_segs)
988{
989 struct file *file = iocb->ki_filp;
990 struct inode *inode = file->f_mapping->host;
991 struct gfs2_inode *ip = GFS2_I(inode);
992 struct gfs2_holder gh;
993 int rv;
994
995 /*
996 * Deferred lock, even if its a write, since we do no allocation
997 * on this path. All we need change is atime, and this lock mode
998 * ensures that other nodes have flushed their buffered read caches
999 * (i.e. their page cache entries for this inode). We do not,
1000 * unfortunately have the option of only flushing a range like
1001 * the VFS does.
1002 */
1003 gfs2_holder_init(ip->i_gl, LM_ST_DEFERRED, 0, &gh);
1004 rv = gfs2_glock_nq(&gh);
1005 if (rv)
1006 return rv;
1007 rv = gfs2_ok_for_dio(ip, rw, offset);
1008 if (rv != 1)
1009 goto out; /* dio not valid, fall back to buffered i/o */
1010
1011 rv = blockdev_direct_IO_no_locking(rw, iocb, inode, inode->i_sb->s_bdev,
1012 iov, offset, nr_segs,
1013 gfs2_get_block_direct, NULL);
1014out:
1015 gfs2_glock_dq_m(1, &gh);
1016 gfs2_holder_uninit(&gh);
1017 return rv;
1018}
1019
1020/**
1021 * gfs2_releasepage - free the metadata associated with a page
1022 * @page: the page that's being released
1023 * @gfp_mask: passed from Linux VFS, ignored by us
1024 *
1025 * Call try_to_free_buffers() if the buffers in this page can be
1026 * released.
1027 *
1028 * Returns: 0
1029 */
1030
1031int gfs2_releasepage(struct page *page, gfp_t gfp_mask)
1032{
1033 struct inode *aspace = page->mapping->host;
1034 struct gfs2_sbd *sdp = aspace->i_sb->s_fs_info;
1035 struct buffer_head *bh, *head;
1036 struct gfs2_bufdata *bd;
1037
1038 if (!page_has_buffers(page))
1039 return 0;
1040
1041 gfs2_log_lock(sdp);
1042 head = bh = page_buffers(page);
1043 do {
1044 if (atomic_read(&bh->b_count))
1045 goto cannot_release;
1046 bd = bh->b_private;
1047 if (bd && bd->bd_ail)
1048 goto cannot_release;
1049 gfs2_assert_warn(sdp, !buffer_pinned(bh));
1050 gfs2_assert_warn(sdp, !buffer_dirty(bh));
1051 bh = bh->b_this_page;
1052 } while(bh != head);
1053 gfs2_log_unlock(sdp);
1054
1055 head = bh = page_buffers(page);
1056 do {
1057 gfs2_log_lock(sdp);
1058 bd = bh->b_private;
1059 if (bd) {
1060 gfs2_assert_warn(sdp, bd->bd_bh == bh);
1061 gfs2_assert_warn(sdp, list_empty(&bd->bd_list_tr));
1062 if (!list_empty(&bd->bd_le.le_list)) {
1063 if (!buffer_pinned(bh))
1064 list_del_init(&bd->bd_le.le_list);
1065 else
1066 bd = NULL;
1067 }
1068 if (bd)
1069 bd->bd_bh = NULL;
1070 bh->b_private = NULL;
1071 }
1072 gfs2_log_unlock(sdp);
1073 if (bd)
1074 kmem_cache_free(gfs2_bufdata_cachep, bd);
1075
1076 bh = bh->b_this_page;
1077 } while (bh != head);
1078
1079 return try_to_free_buffers(page);
1080cannot_release:
1081 gfs2_log_unlock(sdp);
1082 return 0;
1083}
1084
1085static const struct address_space_operations gfs2_writeback_aops = {
1086 .writepage = gfs2_writeback_writepage,
1087 .writepages = gfs2_writeback_writepages,
1088 .readpage = gfs2_readpage,
1089 .readpages = gfs2_readpages,
1090 .sync_page = block_sync_page,
1091 .write_begin = gfs2_write_begin,
1092 .write_end = gfs2_write_end,
1093 .bmap = gfs2_bmap,
1094 .invalidatepage = gfs2_invalidatepage,
1095 .releasepage = gfs2_releasepage,
1096 .direct_IO = gfs2_direct_IO,
1097 .migratepage = buffer_migrate_page,
1098 .is_partially_uptodate = block_is_partially_uptodate,
1099};
1100
1101static const struct address_space_operations gfs2_ordered_aops = {
1102 .writepage = gfs2_ordered_writepage,
1103 .readpage = gfs2_readpage,
1104 .readpages = gfs2_readpages,
1105 .sync_page = block_sync_page,
1106 .write_begin = gfs2_write_begin,
1107 .write_end = gfs2_write_end,
1108 .set_page_dirty = gfs2_set_page_dirty,
1109 .bmap = gfs2_bmap,
1110 .invalidatepage = gfs2_invalidatepage,
1111 .releasepage = gfs2_releasepage,
1112 .direct_IO = gfs2_direct_IO,
1113 .migratepage = buffer_migrate_page,
1114 .is_partially_uptodate = block_is_partially_uptodate,
1115};
1116
1117static const struct address_space_operations gfs2_jdata_aops = {
1118 .writepage = gfs2_jdata_writepage,
1119 .writepages = gfs2_jdata_writepages,
1120 .readpage = gfs2_readpage,
1121 .readpages = gfs2_readpages,
1122 .sync_page = block_sync_page,
1123 .write_begin = gfs2_write_begin,
1124 .write_end = gfs2_write_end,
1125 .set_page_dirty = gfs2_set_page_dirty,
1126 .bmap = gfs2_bmap,
1127 .invalidatepage = gfs2_invalidatepage,
1128 .releasepage = gfs2_releasepage,
1129 .is_partially_uptodate = block_is_partially_uptodate,
1130};
1131
1132void gfs2_set_aops(struct inode *inode)
1133{
1134 struct gfs2_inode *ip = GFS2_I(inode);
1135
1136 if (gfs2_is_writeback(ip))
1137 inode->i_mapping->a_ops = &gfs2_writeback_aops;
1138 else if (gfs2_is_ordered(ip))
1139 inode->i_mapping->a_ops = &gfs2_ordered_aops;
1140 else if (gfs2_is_jdata(ip))
1141 inode->i_mapping->a_ops = &gfs2_jdata_aops;
1142 else
1143 BUG();
1144}
1145