2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
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.
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>
19 #include <linux/writeback.h>
20 #include <linux/swap.h>
21 #include <linux/gfs2_ondisk.h>
22 #include <linux/lm_interface.h>
23 #include <linux/swap.h>
24 #include <linux/pagevec.h>
33 #include "ops_address.h"
42 static void gfs2_page_add_databufs(struct gfs2_inode
*ip
, struct page
*page
,
43 unsigned int from
, unsigned int to
)
45 struct buffer_head
*head
= page_buffers(page
);
46 unsigned int bsize
= head
->b_size
;
47 struct buffer_head
*bh
;
48 unsigned int start
, end
;
50 for (bh
= head
, start
= 0; bh
!= head
|| !start
;
51 bh
= bh
->b_this_page
, start
= end
) {
53 if (end
<= from
|| start
>= to
)
55 if (gfs2_is_jdata(ip
))
56 set_buffer_uptodate(bh
);
57 gfs2_trans_add_bh(ip
->i_gl
, bh
, 0);
62 * gfs2_get_block - Fills in a buffer head with details about a block
64 * @lblock: The block number to look up
65 * @bh_result: The buffer head to return the result in
66 * @create: Non-zero if we may add block to the file
71 int gfs2_get_block(struct inode
*inode
, sector_t lblock
,
72 struct buffer_head
*bh_result
, int create
)
74 return gfs2_block_map(inode
, lblock
, create
, bh_result
);
78 * gfs2_get_block_noalloc - Fills in a buffer head with details about a block
80 * @lblock: The block number to look up
81 * @bh_result: The buffer head to return the result in
82 * @create: Non-zero if we may add block to the file
87 static int gfs2_get_block_noalloc(struct inode
*inode
, sector_t lblock
,
88 struct buffer_head
*bh_result
, int create
)
92 error
= gfs2_block_map(inode
, lblock
, 0, bh_result
);
95 if (!buffer_mapped(bh_result
))
100 static int gfs2_get_block_direct(struct inode
*inode
, sector_t lblock
,
101 struct buffer_head
*bh_result
, int create
)
103 return gfs2_block_map(inode
, lblock
, 0, bh_result
);
107 * gfs2_writepage_common - Common bits of writepage
108 * @page: The page to be written
109 * @wbc: The writeback control
111 * Returns: 1 if writepage is ok, otherwise an error code or zero if no error.
114 static int gfs2_writepage_common(struct page
*page
,
115 struct writeback_control
*wbc
)
117 struct inode
*inode
= page
->mapping
->host
;
118 struct gfs2_inode
*ip
= GFS2_I(inode
);
119 struct gfs2_sbd
*sdp
= GFS2_SB(inode
);
120 loff_t i_size
= i_size_read(inode
);
121 pgoff_t end_index
= i_size
>> PAGE_CACHE_SHIFT
;
125 if (gfs2_assert_withdraw(sdp
, gfs2_glock_is_held_excl(ip
->i_gl
)))
128 if (current
->journal_info
)
130 /* Is the page fully outside i_size? (truncate in progress) */
131 offset
= i_size
& (PAGE_CACHE_SIZE
-1);
132 if (page
->index
> end_index
|| (page
->index
== end_index
&& !offset
)) {
133 page
->mapping
->a_ops
->invalidatepage(page
, 0);
138 redirty_page_for_writepage(wbc
, page
);
145 * gfs2_writeback_writepage - Write page for writeback mappings
147 * @wbc: The writeback control
151 static int gfs2_writeback_writepage(struct page
*page
,
152 struct writeback_control
*wbc
)
156 ret
= gfs2_writepage_common(page
, wbc
);
160 ret
= mpage_writepage(page
, gfs2_get_block_noalloc
, wbc
);
162 ret
= block_write_full_page(page
, gfs2_get_block_noalloc
, wbc
);
167 * gfs2_ordered_writepage - Write page for ordered data files
168 * @page: The page to write
169 * @wbc: The writeback control
173 static int gfs2_ordered_writepage(struct page
*page
,
174 struct writeback_control
*wbc
)
176 struct inode
*inode
= page
->mapping
->host
;
177 struct gfs2_inode
*ip
= GFS2_I(inode
);
180 ret
= gfs2_writepage_common(page
, wbc
);
184 if (!page_has_buffers(page
)) {
185 create_empty_buffers(page
, inode
->i_sb
->s_blocksize
,
186 (1 << BH_Dirty
)|(1 << BH_Uptodate
));
188 gfs2_page_add_databufs(ip
, page
, 0, inode
->i_sb
->s_blocksize
-1);
189 return block_write_full_page(page
, gfs2_get_block_noalloc
, wbc
);
193 * __gfs2_jdata_writepage - The core of jdata writepage
194 * @page: The page to write
195 * @wbc: The writeback control
197 * This is shared between writepage and writepages and implements the
198 * core of the writepage operation. If a transaction is required then
199 * PageChecked will have been set and the transaction will have
200 * already been started before this is called.
203 static int __gfs2_jdata_writepage(struct page
*page
, struct writeback_control
*wbc
)
205 struct inode
*inode
= page
->mapping
->host
;
206 struct gfs2_inode
*ip
= GFS2_I(inode
);
207 struct gfs2_sbd
*sdp
= GFS2_SB(inode
);
209 if (PageChecked(page
)) {
210 ClearPageChecked(page
);
211 if (!page_has_buffers(page
)) {
212 create_empty_buffers(page
, inode
->i_sb
->s_blocksize
,
213 (1 << BH_Dirty
)|(1 << BH_Uptodate
));
215 gfs2_page_add_databufs(ip
, page
, 0, sdp
->sd_vfs
->s_blocksize
-1);
217 return block_write_full_page(page
, gfs2_get_block_noalloc
, wbc
);
221 * gfs2_jdata_writepage - Write complete page
222 * @page: Page to write
228 static int gfs2_jdata_writepage(struct page
*page
, struct writeback_control
*wbc
)
230 struct inode
*inode
= page
->mapping
->host
;
231 struct gfs2_sbd
*sdp
= GFS2_SB(inode
);
235 error
= gfs2_writepage_common(page
, wbc
);
239 if (PageChecked(page
)) {
240 if (wbc
->sync_mode
!= WB_SYNC_ALL
)
242 error
= gfs2_trans_begin(sdp
, RES_DINODE
+ 1, 0);
247 error
= __gfs2_jdata_writepage(page
, wbc
);
253 redirty_page_for_writepage(wbc
, page
);
259 * gfs2_writeback_writepages - Write a bunch of dirty pages back to disk
260 * @mapping: The mapping to write
261 * @wbc: Write-back control
263 * For the data=writeback case we can already ignore buffer heads
264 * and write whole extents at once. This is a big reduction in the
265 * number of I/O requests we send and the bmap calls we make in this case.
267 static int gfs2_writeback_writepages(struct address_space
*mapping
,
268 struct writeback_control
*wbc
)
270 return mpage_writepages(mapping
, wbc
, gfs2_get_block_noalloc
);
274 * gfs2_write_jdata_pagevec - Write back a pagevec's worth of pages
275 * @mapping: The mapping
276 * @wbc: The writeback control
277 * @writepage: The writepage function to call for each page
278 * @pvec: The vector of pages
279 * @nr_pages: The number of pages to write
281 * Returns: non-zero if loop should terminate, zero otherwise
284 static int gfs2_write_jdata_pagevec(struct address_space
*mapping
,
285 struct writeback_control
*wbc
,
286 struct pagevec
*pvec
,
287 int nr_pages
, pgoff_t end
)
289 struct inode
*inode
= mapping
->host
;
290 struct gfs2_sbd
*sdp
= GFS2_SB(inode
);
291 loff_t i_size
= i_size_read(inode
);
292 pgoff_t end_index
= i_size
>> PAGE_CACHE_SHIFT
;
293 unsigned offset
= i_size
& (PAGE_CACHE_SIZE
-1);
294 unsigned nrblocks
= nr_pages
* (PAGE_CACHE_SIZE
/inode
->i_sb
->s_blocksize
);
295 struct backing_dev_info
*bdi
= mapping
->backing_dev_info
;
299 ret
= gfs2_trans_begin(sdp
, nrblocks
, 0);
303 for(i
= 0; i
< nr_pages
; i
++) {
304 struct page
*page
= pvec
->pages
[i
];
308 if (unlikely(page
->mapping
!= mapping
)) {
313 if (!wbc
->range_cyclic
&& page
->index
> end
) {
319 if (wbc
->sync_mode
!= WB_SYNC_NONE
)
320 wait_on_page_writeback(page
);
322 if (PageWriteback(page
) ||
323 !clear_page_dirty_for_io(page
)) {
328 /* Is the page fully outside i_size? (truncate in progress) */
329 if (page
->index
> end_index
|| (page
->index
== end_index
&& !offset
)) {
330 page
->mapping
->a_ops
->invalidatepage(page
, 0);
335 ret
= __gfs2_jdata_writepage(page
, wbc
);
337 if (ret
|| (--(wbc
->nr_to_write
) <= 0))
339 if (wbc
->nonblocking
&& bdi_write_congested(bdi
)) {
340 wbc
->encountered_congestion
= 1;
350 * gfs2_write_cache_jdata - Like write_cache_pages but different
351 * @mapping: The mapping to write
352 * @wbc: The writeback control
353 * @writepage: The writepage function to call
354 * @data: The data to pass to writepage
356 * The reason that we use our own function here is that we need to
357 * start transactions before we grab page locks. This allows us
358 * to get the ordering right.
361 static int gfs2_write_cache_jdata(struct address_space
*mapping
,
362 struct writeback_control
*wbc
)
364 struct backing_dev_info
*bdi
= mapping
->backing_dev_info
;
374 if (wbc
->nonblocking
&& bdi_write_congested(bdi
)) {
375 wbc
->encountered_congestion
= 1;
379 pagevec_init(&pvec
, 0);
380 if (wbc
->range_cyclic
) {
381 index
= mapping
->writeback_index
; /* Start from prev offset */
384 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
385 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
386 if (wbc
->range_start
== 0 && wbc
->range_end
== LLONG_MAX
)
392 while (!done
&& (index
<= end
) &&
393 (nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
,
395 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1))) {
397 ret
= gfs2_write_jdata_pagevec(mapping
, wbc
, &pvec
, nr_pages
, end
);
403 pagevec_release(&pvec
);
407 if (!scanned
&& !done
) {
409 * We hit the last page and there is more work to be done: wrap
410 * back to the start of the file
417 if (wbc
->range_cyclic
|| (range_whole
&& wbc
->nr_to_write
> 0))
418 mapping
->writeback_index
= index
;
424 * gfs2_jdata_writepages - Write a bunch of dirty pages back to disk
425 * @mapping: The mapping to write
426 * @wbc: The writeback control
430 static int gfs2_jdata_writepages(struct address_space
*mapping
,
431 struct writeback_control
*wbc
)
433 struct gfs2_inode
*ip
= GFS2_I(mapping
->host
);
434 struct gfs2_sbd
*sdp
= GFS2_SB(mapping
->host
);
437 ret
= gfs2_write_cache_jdata(mapping
, wbc
);
438 if (ret
== 0 && wbc
->sync_mode
== WB_SYNC_ALL
) {
439 gfs2_log_flush(sdp
, ip
->i_gl
);
440 ret
= gfs2_write_cache_jdata(mapping
, wbc
);
446 * stuffed_readpage - Fill in a Linux page with stuffed file data
453 static int stuffed_readpage(struct gfs2_inode
*ip
, struct page
*page
)
455 struct buffer_head
*dibh
;
460 * Due to the order of unstuffing files and ->nopage(), we can be
461 * asked for a zero page in the case of a stuffed file being extended,
462 * so we need to supply one here. It doesn't happen often.
464 if (unlikely(page
->index
)) {
465 zero_user_page(page
, 0, PAGE_CACHE_SIZE
, KM_USER0
);
469 error
= gfs2_meta_inode_buffer(ip
, &dibh
);
473 kaddr
= kmap_atomic(page
, KM_USER0
);
474 memcpy(kaddr
, dibh
->b_data
+ sizeof(struct gfs2_dinode
),
476 memset(kaddr
+ ip
->i_di
.di_size
, 0, PAGE_CACHE_SIZE
- ip
->i_di
.di_size
);
477 kunmap_atomic(kaddr
, KM_USER0
);
478 flush_dcache_page(page
);
480 SetPageUptodate(page
);
487 * __gfs2_readpage - readpage
488 * @file: The file to read a page for
489 * @page: The page to read
491 * This is the core of gfs2's readpage. Its used by the internal file
492 * reading code as in that case we already hold the glock. Also its
493 * called by gfs2_readpage() once the required lock has been granted.
497 static int __gfs2_readpage(void *file
, struct page
*page
)
499 struct gfs2_inode
*ip
= GFS2_I(page
->mapping
->host
);
500 struct gfs2_sbd
*sdp
= GFS2_SB(page
->mapping
->host
);
503 if (gfs2_is_stuffed(ip
)) {
504 error
= stuffed_readpage(ip
, page
);
507 error
= mpage_readpage(page
, gfs2_get_block
);
510 if (unlikely(test_bit(SDF_SHUTDOWN
, &sdp
->sd_flags
)))
517 * gfs2_readpage - read a page of a file
518 * @file: The file to read
519 * @page: The page of the file
521 * This deals with the locking required. We use a trylock in order to
522 * avoid the page lock / glock ordering problems returning AOP_TRUNCATED_PAGE
523 * in the event that we are unable to get the lock.
526 static int gfs2_readpage(struct file
*file
, struct page
*page
)
528 struct gfs2_inode
*ip
= GFS2_I(page
->mapping
->host
);
529 struct gfs2_holder gh
;
532 gfs2_holder_init(ip
->i_gl
, LM_ST_SHARED
, GL_ATIME
|LM_FLAG_TRY_1CB
, &gh
);
533 error
= gfs2_glock_nq_atime(&gh
);
534 if (unlikely(error
)) {
538 error
= __gfs2_readpage(file
, page
);
541 gfs2_holder_uninit(&gh
);
542 if (error
== GLR_TRYFAILED
) {
544 return AOP_TRUNCATED_PAGE
;
550 * gfs2_internal_read - read an internal file
551 * @ip: The gfs2 inode
552 * @ra_state: The readahead state (or NULL for no readahead)
553 * @buf: The buffer to fill
554 * @pos: The file position
555 * @size: The amount to read
559 int gfs2_internal_read(struct gfs2_inode
*ip
, struct file_ra_state
*ra_state
,
560 char *buf
, loff_t
*pos
, unsigned size
)
562 struct address_space
*mapping
= ip
->i_inode
.i_mapping
;
563 unsigned long index
= *pos
/ PAGE_CACHE_SIZE
;
564 unsigned offset
= *pos
& (PAGE_CACHE_SIZE
- 1);
572 if (offset
+ size
> PAGE_CACHE_SIZE
)
573 amt
= PAGE_CACHE_SIZE
- offset
;
574 page
= read_cache_page(mapping
, index
, __gfs2_readpage
, NULL
);
576 return PTR_ERR(page
);
577 p
= kmap_atomic(page
, KM_USER0
);
578 memcpy(buf
+ copied
, p
+ offset
, amt
);
579 kunmap_atomic(p
, KM_USER0
);
580 mark_page_accessed(page
);
581 page_cache_release(page
);
585 } while(copied
< size
);
591 * gfs2_readpages - Read a bunch of pages at once
594 * 1. This is only for readahead, so we can simply ignore any things
595 * which are slightly inconvenient (such as locking conflicts between
596 * the page lock and the glock) and return having done no I/O. Its
597 * obviously not something we'd want to do on too regular a basis.
598 * Any I/O we ignore at this time will be done via readpage later.
599 * 2. We don't handle stuffed files here we let readpage do the honours.
600 * 3. mpage_readpages() does most of the heavy lifting in the common case.
601 * 4. gfs2_get_block() is relied upon to set BH_Boundary in the right places.
604 static int gfs2_readpages(struct file
*file
, struct address_space
*mapping
,
605 struct list_head
*pages
, unsigned nr_pages
)
607 struct inode
*inode
= mapping
->host
;
608 struct gfs2_inode
*ip
= GFS2_I(inode
);
609 struct gfs2_sbd
*sdp
= GFS2_SB(inode
);
610 struct gfs2_holder gh
;
613 gfs2_holder_init(ip
->i_gl
, LM_ST_SHARED
, GL_ATIME
, &gh
);
614 ret
= gfs2_glock_nq_atime(&gh
);
617 if (!gfs2_is_stuffed(ip
))
618 ret
= mpage_readpages(mapping
, pages
, nr_pages
, gfs2_get_block
);
621 gfs2_holder_uninit(&gh
);
622 if (unlikely(test_bit(SDF_SHUTDOWN
, &sdp
->sd_flags
)))
628 * gfs2_write_begin - Begin to write to a file
629 * @file: The file to write to
630 * @mapping: The mapping in which to write
631 * @pos: The file offset at which to start writing
632 * @len: Length of the write
633 * @flags: Various flags
634 * @pagep: Pointer to return the page
635 * @fsdata: Pointer to return fs data (unused by GFS2)
640 static int gfs2_write_begin(struct file
*file
, struct address_space
*mapping
,
641 loff_t pos
, unsigned len
, unsigned flags
,
642 struct page
**pagep
, void **fsdata
)
644 struct gfs2_inode
*ip
= GFS2_I(mapping
->host
);
645 struct gfs2_sbd
*sdp
= GFS2_SB(mapping
->host
);
646 unsigned int data_blocks
, ind_blocks
, rblocks
;
649 struct gfs2_alloc
*al
;
650 pgoff_t index
= pos
>> PAGE_CACHE_SHIFT
;
651 unsigned from
= pos
& (PAGE_CACHE_SIZE
- 1);
652 unsigned to
= from
+ len
;
655 gfs2_holder_init(ip
->i_gl
, LM_ST_EXCLUSIVE
, GL_ATIME
, &ip
->i_gh
);
656 error
= gfs2_glock_nq_atime(&ip
->i_gh
);
661 page
= __grab_cache_page(mapping
, index
);
666 gfs2_write_calc_reserv(ip
, len
, &data_blocks
, &ind_blocks
);
668 error
= gfs2_write_alloc_required(ip
, pos
, len
, &alloc_required
);
673 ip
->i_alloc
.al_requested
= 0;
674 if (alloc_required
) {
675 al
= gfs2_alloc_get(ip
);
677 error
= gfs2_quota_lock(ip
, NO_QUOTA_CHANGE
, NO_QUOTA_CHANGE
);
681 error
= gfs2_quota_check(ip
, ip
->i_inode
.i_uid
, ip
->i_inode
.i_gid
);
685 al
->al_requested
= data_blocks
+ ind_blocks
;
686 error
= gfs2_inplace_reserve(ip
);
691 rblocks
= RES_DINODE
+ ind_blocks
;
692 if (gfs2_is_jdata(ip
))
693 rblocks
+= data_blocks
? data_blocks
: 1;
694 if (ind_blocks
|| data_blocks
)
695 rblocks
+= RES_STATFS
+ RES_QUOTA
;
697 error
= gfs2_trans_begin(sdp
, rblocks
,
698 PAGE_CACHE_SIZE
/sdp
->sd_sb
.sb_bsize
);
702 if (gfs2_is_stuffed(ip
)) {
703 if (pos
+ len
> sdp
->sd_sb
.sb_bsize
- sizeof(struct gfs2_dinode
)) {
704 error
= gfs2_unstuff_dinode(ip
, page
);
707 } else if (!PageUptodate(page
))
708 error
= stuffed_readpage(ip
, page
);
713 error
= block_prepare_write(page
, from
, to
, gfs2_get_block
);
719 if (alloc_required
) {
720 gfs2_inplace_release(ip
);
722 gfs2_quota_unlock(ip
);
727 page_cache_release(page
);
728 if (pos
+ len
> ip
->i_inode
.i_size
)
729 vmtruncate(&ip
->i_inode
, ip
->i_inode
.i_size
);
731 gfs2_glock_dq_m(1, &ip
->i_gh
);
733 gfs2_holder_uninit(&ip
->i_gh
);
740 * adjust_fs_space - Adjusts the free space available due to gfs2_grow
741 * @inode: the rindex inode
743 static void adjust_fs_space(struct inode
*inode
)
745 struct gfs2_sbd
*sdp
= inode
->i_sb
->s_fs_info
;
746 struct gfs2_statfs_change_host
*m_sc
= &sdp
->sd_statfs_master
;
747 struct gfs2_statfs_change_host
*l_sc
= &sdp
->sd_statfs_local
;
748 u64 fs_total
, new_free
;
750 /* Total up the file system space, according to the latest rindex. */
751 fs_total
= gfs2_ri_total(sdp
);
753 spin_lock(&sdp
->sd_statfs_spin
);
754 if (fs_total
> (m_sc
->sc_total
+ l_sc
->sc_total
))
755 new_free
= fs_total
- (m_sc
->sc_total
+ l_sc
->sc_total
);
758 spin_unlock(&sdp
->sd_statfs_spin
);
759 fs_warn(sdp
, "File system extended by %llu blocks.\n",
760 (unsigned long long)new_free
);
761 gfs2_statfs_change(sdp
, new_free
, new_free
, 0);
765 * gfs2_stuffed_write_end - Write end for stuffed files
767 * @dibh: The buffer_head containing the on-disk inode
768 * @pos: The file position
769 * @len: The length of the write
770 * @copied: How much was actually copied by the VFS
773 * This copies the data from the page into the inode block after
774 * the inode data structure itself.
778 static int gfs2_stuffed_write_end(struct inode
*inode
, struct buffer_head
*dibh
,
779 loff_t pos
, unsigned len
, unsigned copied
,
782 struct gfs2_inode
*ip
= GFS2_I(inode
);
783 struct gfs2_sbd
*sdp
= GFS2_SB(inode
);
784 u64 to
= pos
+ copied
;
786 unsigned char *buf
= dibh
->b_data
+ sizeof(struct gfs2_dinode
);
787 struct gfs2_dinode
*di
= (struct gfs2_dinode
*)dibh
->b_data
;
789 BUG_ON((pos
+ len
) > (dibh
->b_size
- sizeof(struct gfs2_dinode
)));
790 kaddr
= kmap_atomic(page
, KM_USER0
);
791 memcpy(buf
+ pos
, kaddr
+ pos
, copied
);
792 memset(kaddr
+ pos
+ copied
, 0, len
- copied
);
793 flush_dcache_page(page
);
794 kunmap_atomic(kaddr
, KM_USER0
);
796 if (!PageUptodate(page
))
797 SetPageUptodate(page
);
799 page_cache_release(page
);
801 if (inode
->i_size
< to
) {
802 i_size_write(inode
, to
);
803 ip
->i_di
.di_size
= inode
->i_size
;
804 di
->di_size
= cpu_to_be64(inode
->i_size
);
805 mark_inode_dirty(inode
);
808 if (inode
== sdp
->sd_rindex
)
809 adjust_fs_space(inode
);
813 gfs2_glock_dq(&ip
->i_gh
);
814 gfs2_holder_uninit(&ip
->i_gh
);
820 * @file: The file to write to
821 * @mapping: The address space to write to
822 * @pos: The file position
823 * @len: The length of the data
825 * @page: The page that has been written
826 * @fsdata: The fsdata (unused in GFS2)
828 * The main write_end function for GFS2. We have a separate one for
829 * stuffed files as they are slightly different, otherwise we just
830 * put our locking around the VFS provided functions.
835 static int gfs2_write_end(struct file
*file
, struct address_space
*mapping
,
836 loff_t pos
, unsigned len
, unsigned copied
,
837 struct page
*page
, void *fsdata
)
839 struct inode
*inode
= page
->mapping
->host
;
840 struct gfs2_inode
*ip
= GFS2_I(inode
);
841 struct gfs2_sbd
*sdp
= GFS2_SB(inode
);
842 struct buffer_head
*dibh
;
843 struct gfs2_alloc
*al
= &ip
->i_alloc
;
844 struct gfs2_dinode
*di
;
845 unsigned int from
= pos
& (PAGE_CACHE_SIZE
- 1);
846 unsigned int to
= from
+ len
;
849 BUG_ON(gfs2_glock_is_locked_by_me(ip
->i_gl
) == 0);
851 ret
= gfs2_meta_inode_buffer(ip
, &dibh
);
854 page_cache_release(page
);
858 gfs2_trans_add_bh(ip
->i_gl
, dibh
, 1);
860 if (gfs2_is_stuffed(ip
))
861 return gfs2_stuffed_write_end(inode
, dibh
, pos
, len
, copied
, page
);
863 if (!gfs2_is_writeback(ip
))
864 gfs2_page_add_databufs(ip
, page
, from
, to
);
866 ret
= generic_write_end(file
, mapping
, pos
, len
, copied
, page
, fsdata
);
868 if (likely(ret
>= 0)) {
870 if ((pos
+ copied
) > inode
->i_size
) {
871 di
= (struct gfs2_dinode
*)dibh
->b_data
;
872 ip
->i_di
.di_size
= inode
->i_size
;
873 di
->di_size
= cpu_to_be64(inode
->i_size
);
874 mark_inode_dirty(inode
);
878 if (inode
== sdp
->sd_rindex
)
879 adjust_fs_space(inode
);
884 if (al
->al_requested
) {
885 gfs2_inplace_release(ip
);
886 gfs2_quota_unlock(ip
);
889 gfs2_glock_dq(&ip
->i_gh
);
890 gfs2_holder_uninit(&ip
->i_gh
);
895 * gfs2_set_page_dirty - Page dirtying function
896 * @page: The page to dirty
898 * Returns: 1 if it dirtyed the page, or 0 otherwise
901 static int gfs2_set_page_dirty(struct page
*page
)
903 SetPageChecked(page
);
904 return __set_page_dirty_buffers(page
);
908 * gfs2_bmap - Block map function
909 * @mapping: Address space info
910 * @lblock: The block to map
912 * Returns: The disk address for the block or 0 on hole or error
915 static sector_t
gfs2_bmap(struct address_space
*mapping
, sector_t lblock
)
917 struct gfs2_inode
*ip
= GFS2_I(mapping
->host
);
918 struct gfs2_holder i_gh
;
922 error
= gfs2_glock_nq_init(ip
->i_gl
, LM_ST_SHARED
, LM_FLAG_ANY
, &i_gh
);
926 if (!gfs2_is_stuffed(ip
))
927 dblock
= generic_block_bmap(mapping
, lblock
, gfs2_get_block
);
929 gfs2_glock_dq_uninit(&i_gh
);
934 static void gfs2_discard(struct gfs2_sbd
*sdp
, struct buffer_head
*bh
)
936 struct gfs2_bufdata
*bd
;
940 clear_buffer_dirty(bh
);
943 if (!list_empty(&bd
->bd_le
.le_list
) && !buffer_pinned(bh
))
944 list_del_init(&bd
->bd_le
.le_list
);
946 gfs2_remove_from_journal(bh
, current
->journal_info
, 0);
949 clear_buffer_mapped(bh
);
950 clear_buffer_req(bh
);
951 clear_buffer_new(bh
);
952 gfs2_log_unlock(sdp
);
956 static void gfs2_invalidatepage(struct page
*page
, unsigned long offset
)
958 struct gfs2_sbd
*sdp
= GFS2_SB(page
->mapping
->host
);
959 struct buffer_head
*bh
, *head
;
960 unsigned long pos
= 0;
962 BUG_ON(!PageLocked(page
));
964 ClearPageChecked(page
);
965 if (!page_has_buffers(page
))
968 bh
= head
= page_buffers(page
);
971 gfs2_discard(sdp
, bh
);
973 bh
= bh
->b_this_page
;
974 } while (bh
!= head
);
977 try_to_release_page(page
, 0);
981 * gfs2_ok_for_dio - check that dio is valid on this file
984 * @offset: The offset at which we are reading or writing
986 * Returns: 0 (to ignore the i/o request and thus fall back to buffered i/o)
987 * 1 (to accept the i/o request)
989 static int gfs2_ok_for_dio(struct gfs2_inode
*ip
, int rw
, loff_t offset
)
992 * Should we return an error here? I can't see that O_DIRECT for
993 * a stuffed file makes any sense. For now we'll silently fall
994 * back to buffered I/O
996 if (gfs2_is_stuffed(ip
))
999 if (offset
> i_size_read(&ip
->i_inode
))
1006 static ssize_t
gfs2_direct_IO(int rw
, struct kiocb
*iocb
,
1007 const struct iovec
*iov
, loff_t offset
,
1008 unsigned long nr_segs
)
1010 struct file
*file
= iocb
->ki_filp
;
1011 struct inode
*inode
= file
->f_mapping
->host
;
1012 struct gfs2_inode
*ip
= GFS2_I(inode
);
1013 struct gfs2_holder gh
;
1017 * Deferred lock, even if its a write, since we do no allocation
1018 * on this path. All we need change is atime, and this lock mode
1019 * ensures that other nodes have flushed their buffered read caches
1020 * (i.e. their page cache entries for this inode). We do not,
1021 * unfortunately have the option of only flushing a range like
1024 gfs2_holder_init(ip
->i_gl
, LM_ST_DEFERRED
, GL_ATIME
, &gh
);
1025 rv
= gfs2_glock_nq_atime(&gh
);
1028 rv
= gfs2_ok_for_dio(ip
, rw
, offset
);
1030 goto out
; /* dio not valid, fall back to buffered i/o */
1032 rv
= blockdev_direct_IO_no_locking(rw
, iocb
, inode
, inode
->i_sb
->s_bdev
,
1033 iov
, offset
, nr_segs
,
1034 gfs2_get_block_direct
, NULL
);
1036 gfs2_glock_dq_m(1, &gh
);
1037 gfs2_holder_uninit(&gh
);
1042 * gfs2_releasepage - free the metadata associated with a page
1043 * @page: the page that's being released
1044 * @gfp_mask: passed from Linux VFS, ignored by us
1046 * Call try_to_free_buffers() if the buffers in this page can be
1052 int gfs2_releasepage(struct page
*page
, gfp_t gfp_mask
)
1054 struct inode
*aspace
= page
->mapping
->host
;
1055 struct gfs2_sbd
*sdp
= aspace
->i_sb
->s_fs_info
;
1056 struct buffer_head
*bh
, *head
;
1057 struct gfs2_bufdata
*bd
;
1059 if (!page_has_buffers(page
))
1063 head
= bh
= page_buffers(page
);
1065 if (atomic_read(&bh
->b_count
))
1066 goto cannot_release
;
1068 if (bd
&& bd
->bd_ail
)
1069 goto cannot_release
;
1070 gfs2_assert_warn(sdp
, !buffer_pinned(bh
));
1071 gfs2_assert_warn(sdp
, !buffer_dirty(bh
));
1072 bh
= bh
->b_this_page
;
1073 } while(bh
!= head
);
1074 gfs2_log_unlock(sdp
);
1076 head
= bh
= page_buffers(page
);
1081 gfs2_assert_warn(sdp
, bd
->bd_bh
== bh
);
1082 gfs2_assert_warn(sdp
, list_empty(&bd
->bd_list_tr
));
1083 if (!list_empty(&bd
->bd_le
.le_list
)) {
1084 if (!buffer_pinned(bh
))
1085 list_del_init(&bd
->bd_le
.le_list
);
1091 bh
->b_private
= NULL
;
1093 gfs2_log_unlock(sdp
);
1095 kmem_cache_free(gfs2_bufdata_cachep
, bd
);
1097 bh
= bh
->b_this_page
;
1098 } while (bh
!= head
);
1100 return try_to_free_buffers(page
);
1102 gfs2_log_unlock(sdp
);
1106 static const struct address_space_operations gfs2_writeback_aops
= {
1107 .writepage
= gfs2_writeback_writepage
,
1108 .writepages
= gfs2_writeback_writepages
,
1109 .readpage
= gfs2_readpage
,
1110 .readpages
= gfs2_readpages
,
1111 .sync_page
= block_sync_page
,
1112 .write_begin
= gfs2_write_begin
,
1113 .write_end
= gfs2_write_end
,
1115 .invalidatepage
= gfs2_invalidatepage
,
1116 .releasepage
= gfs2_releasepage
,
1117 .direct_IO
= gfs2_direct_IO
,
1120 static const struct address_space_operations gfs2_ordered_aops
= {
1121 .writepage
= gfs2_ordered_writepage
,
1122 .readpage
= gfs2_readpage
,
1123 .readpages
= gfs2_readpages
,
1124 .sync_page
= block_sync_page
,
1125 .write_begin
= gfs2_write_begin
,
1126 .write_end
= gfs2_write_end
,
1127 .set_page_dirty
= gfs2_set_page_dirty
,
1129 .invalidatepage
= gfs2_invalidatepage
,
1130 .releasepage
= gfs2_releasepage
,
1131 .direct_IO
= gfs2_direct_IO
,
1134 static const struct address_space_operations gfs2_jdata_aops
= {
1135 .writepage
= gfs2_jdata_writepage
,
1136 .writepages
= gfs2_jdata_writepages
,
1137 .readpage
= gfs2_readpage
,
1138 .readpages
= gfs2_readpages
,
1139 .sync_page
= block_sync_page
,
1140 .write_begin
= gfs2_write_begin
,
1141 .write_end
= gfs2_write_end
,
1142 .set_page_dirty
= gfs2_set_page_dirty
,
1144 .invalidatepage
= gfs2_invalidatepage
,
1145 .releasepage
= gfs2_releasepage
,
1148 void gfs2_set_aops(struct inode
*inode
)
1150 struct gfs2_inode
*ip
= GFS2_I(inode
);
1152 if (gfs2_is_writeback(ip
))
1153 inode
->i_mapping
->a_ops
= &gfs2_writeback_aops
;
1154 else if (gfs2_is_ordered(ip
))
1155 inode
->i_mapping
->a_ops
= &gfs2_ordered_aops
;
1156 else if (gfs2_is_jdata(ip
))
1157 inode
->i_mapping
->a_ops
= &gfs2_jdata_aops
;