1 /* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
4 * Copyright (C) 2002, 2004 Oracle. All rights reserved.
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * General Public License for more details.
16 * You should have received a copy of the GNU General Public
17 * License along with this program; if not, write to the
18 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 * Boston, MA 021110-1307, USA.
23 #include <linux/slab.h>
24 #include <linux/highmem.h>
25 #include <linux/pagemap.h>
26 #include <asm/byteorder.h>
27 #include <linux/swap.h>
28 #include <linux/pipe_fs_i.h>
30 #define MLOG_MASK_PREFIX ML_FILE_IO
31 #include <cluster/masklog.h>
38 #include "extent_map.h"
46 #include "buffer_head_io.h"
48 static int ocfs2_symlink_get_block(struct inode
*inode
, sector_t iblock
,
49 struct buffer_head
*bh_result
, int create
)
53 struct ocfs2_dinode
*fe
= NULL
;
54 struct buffer_head
*bh
= NULL
;
55 struct buffer_head
*buffer_cache_bh
= NULL
;
56 struct ocfs2_super
*osb
= OCFS2_SB(inode
->i_sb
);
59 mlog_entry("(0x%p, %llu, 0x%p, %d)\n", inode
,
60 (unsigned long long)iblock
, bh_result
, create
);
62 BUG_ON(ocfs2_inode_is_fast_symlink(inode
));
64 if ((iblock
<< inode
->i_sb
->s_blocksize_bits
) > PATH_MAX
+ 1) {
65 mlog(ML_ERROR
, "block offset > PATH_MAX: %llu",
66 (unsigned long long)iblock
);
70 status
= ocfs2_read_block(OCFS2_SB(inode
->i_sb
),
71 OCFS2_I(inode
)->ip_blkno
,
72 &bh
, OCFS2_BH_CACHED
, inode
);
77 fe
= (struct ocfs2_dinode
*) bh
->b_data
;
79 if (!OCFS2_IS_VALID_DINODE(fe
)) {
80 mlog(ML_ERROR
, "Invalid dinode #%llu: signature = %.*s\n",
81 (unsigned long long)fe
->i_blkno
, 7, fe
->i_signature
);
85 if ((u64
)iblock
>= ocfs2_clusters_to_blocks(inode
->i_sb
,
86 le32_to_cpu(fe
->i_clusters
))) {
87 mlog(ML_ERROR
, "block offset is outside the allocated size: "
88 "%llu\n", (unsigned long long)iblock
);
92 /* We don't use the page cache to create symlink data, so if
93 * need be, copy it over from the buffer cache. */
94 if (!buffer_uptodate(bh_result
) && ocfs2_inode_is_new(inode
)) {
95 u64 blkno
= le64_to_cpu(fe
->id2
.i_list
.l_recs
[0].e_blkno
) +
97 buffer_cache_bh
= sb_getblk(osb
->sb
, blkno
);
98 if (!buffer_cache_bh
) {
99 mlog(ML_ERROR
, "couldn't getblock for symlink!\n");
103 /* we haven't locked out transactions, so a commit
104 * could've happened. Since we've got a reference on
105 * the bh, even if it commits while we're doing the
106 * copy, the data is still good. */
107 if (buffer_jbd(buffer_cache_bh
)
108 && ocfs2_inode_is_new(inode
)) {
109 kaddr
= kmap_atomic(bh_result
->b_page
, KM_USER0
);
111 mlog(ML_ERROR
, "couldn't kmap!\n");
114 memcpy(kaddr
+ (bh_result
->b_size
* iblock
),
115 buffer_cache_bh
->b_data
,
117 kunmap_atomic(kaddr
, KM_USER0
);
118 set_buffer_uptodate(bh_result
);
120 brelse(buffer_cache_bh
);
123 map_bh(bh_result
, inode
->i_sb
,
124 le64_to_cpu(fe
->id2
.i_list
.l_recs
[0].e_blkno
) + iblock
);
136 static int ocfs2_get_block(struct inode
*inode
, sector_t iblock
,
137 struct buffer_head
*bh_result
, int create
)
140 unsigned int ext_flags
;
141 u64 p_blkno
, past_eof
;
142 struct ocfs2_super
*osb
= OCFS2_SB(inode
->i_sb
);
144 mlog_entry("(0x%p, %llu, 0x%p, %d)\n", inode
,
145 (unsigned long long)iblock
, bh_result
, create
);
147 if (OCFS2_I(inode
)->ip_flags
& OCFS2_INODE_SYSTEM_FILE
)
148 mlog(ML_NOTICE
, "get_block on system inode 0x%p (%lu)\n",
149 inode
, inode
->i_ino
);
151 if (S_ISLNK(inode
->i_mode
)) {
152 /* this always does I/O for some reason. */
153 err
= ocfs2_symlink_get_block(inode
, iblock
, bh_result
, create
);
157 err
= ocfs2_extent_map_get_blocks(inode
, iblock
, &p_blkno
, NULL
,
160 mlog(ML_ERROR
, "Error %d from get_blocks(0x%p, %llu, 1, "
161 "%llu, NULL)\n", err
, inode
, (unsigned long long)iblock
,
162 (unsigned long long)p_blkno
);
167 * ocfs2 never allocates in this function - the only time we
168 * need to use BH_New is when we're extending i_size on a file
169 * system which doesn't support holes, in which case BH_New
170 * allows block_prepare_write() to zero.
172 mlog_bug_on_msg(create
&& p_blkno
== 0 && ocfs2_sparse_alloc(osb
),
173 "ino %lu, iblock %llu\n", inode
->i_ino
,
174 (unsigned long long)iblock
);
176 /* Treat the unwritten extent as a hole for zeroing purposes. */
177 if (p_blkno
&& !(ext_flags
& OCFS2_EXT_UNWRITTEN
))
178 map_bh(bh_result
, inode
->i_sb
, p_blkno
);
180 if (!ocfs2_sparse_alloc(osb
)) {
184 "iblock = %llu p_blkno = %llu blkno=(%llu)\n",
185 (unsigned long long)iblock
,
186 (unsigned long long)p_blkno
,
187 (unsigned long long)OCFS2_I(inode
)->ip_blkno
);
188 mlog(ML_ERROR
, "Size %llu, clusters %u\n", (unsigned long long)i_size_read(inode
), OCFS2_I(inode
)->ip_clusters
);
192 past_eof
= ocfs2_blocks_for_bytes(inode
->i_sb
, i_size_read(inode
));
193 mlog(0, "Inode %lu, past_eof = %llu\n", inode
->i_ino
,
194 (unsigned long long)past_eof
);
196 if (create
&& (iblock
>= past_eof
))
197 set_buffer_new(bh_result
);
208 static int ocfs2_readpage(struct file
*file
, struct page
*page
)
210 struct inode
*inode
= page
->mapping
->host
;
211 loff_t start
= (loff_t
)page
->index
<< PAGE_CACHE_SHIFT
;
214 mlog_entry("(0x%p, %lu)\n", file
, (page
? page
->index
: 0));
216 ret
= ocfs2_meta_lock_with_page(inode
, NULL
, 0, page
);
218 if (ret
== AOP_TRUNCATED_PAGE
)
224 down_read(&OCFS2_I(inode
)->ip_alloc_sem
);
227 * i_size might have just been updated as we grabed the meta lock. We
228 * might now be discovering a truncate that hit on another node.
229 * block_read_full_page->get_block freaks out if it is asked to read
230 * beyond the end of a file, so we check here. Callers
231 * (generic_file_read, fault->nopage) are clever enough to check i_size
232 * and notice that the page they just read isn't needed.
234 * XXX sys_readahead() seems to get that wrong?
236 if (start
>= i_size_read(inode
)) {
237 char *addr
= kmap(page
);
238 memset(addr
, 0, PAGE_SIZE
);
239 flush_dcache_page(page
);
241 SetPageUptodate(page
);
246 ret
= ocfs2_data_lock_with_page(inode
, 0, page
);
248 if (ret
== AOP_TRUNCATED_PAGE
)
254 ret
= block_read_full_page(page
, ocfs2_get_block
);
257 ocfs2_data_unlock(inode
, 0);
259 up_read(&OCFS2_I(inode
)->ip_alloc_sem
);
260 ocfs2_meta_unlock(inode
, 0);
268 /* Note: Because we don't support holes, our allocation has
269 * already happened (allocation writes zeros to the file data)
270 * so we don't have to worry about ordered writes in
273 * ->writepage is called during the process of invalidating the page cache
274 * during blocked lock processing. It can't block on any cluster locks
275 * to during block mapping. It's relying on the fact that the block
276 * mapping can't have disappeared under the dirty pages that it is
277 * being asked to write back.
279 static int ocfs2_writepage(struct page
*page
, struct writeback_control
*wbc
)
283 mlog_entry("(0x%p)\n", page
);
285 ret
= block_write_full_page(page
, ocfs2_get_block
, wbc
);
293 * This is called from ocfs2_write_zero_page() which has handled it's
294 * own cluster locking and has ensured allocation exists for those
295 * blocks to be written.
297 int ocfs2_prepare_write_nolock(struct inode
*inode
, struct page
*page
,
298 unsigned from
, unsigned to
)
302 down_read(&OCFS2_I(inode
)->ip_alloc_sem
);
304 ret
= block_prepare_write(page
, from
, to
, ocfs2_get_block
);
306 up_read(&OCFS2_I(inode
)->ip_alloc_sem
);
311 /* Taken from ext3. We don't necessarily need the full blown
312 * functionality yet, but IMHO it's better to cut and paste the whole
313 * thing so we can avoid introducing our own bugs (and easily pick up
314 * their fixes when they happen) --Mark */
315 int walk_page_buffers( handle_t
*handle
,
316 struct buffer_head
*head
,
320 int (*fn
)( handle_t
*handle
,
321 struct buffer_head
*bh
))
323 struct buffer_head
*bh
;
324 unsigned block_start
, block_end
;
325 unsigned blocksize
= head
->b_size
;
327 struct buffer_head
*next
;
329 for ( bh
= head
, block_start
= 0;
330 ret
== 0 && (bh
!= head
|| !block_start
);
331 block_start
= block_end
, bh
= next
)
333 next
= bh
->b_this_page
;
334 block_end
= block_start
+ blocksize
;
335 if (block_end
<= from
|| block_start
>= to
) {
336 if (partial
&& !buffer_uptodate(bh
))
340 err
= (*fn
)(handle
, bh
);
347 handle_t
*ocfs2_start_walk_page_trans(struct inode
*inode
,
352 struct ocfs2_super
*osb
= OCFS2_SB(inode
->i_sb
);
353 handle_t
*handle
= NULL
;
356 handle
= ocfs2_start_trans(osb
, OCFS2_INODE_UPDATE_CREDITS
);
363 if (ocfs2_should_order_data(inode
)) {
364 ret
= walk_page_buffers(handle
,
367 ocfs2_journal_dirty_data
);
374 ocfs2_commit_trans(osb
, handle
);
375 handle
= ERR_PTR(ret
);
380 static sector_t
ocfs2_bmap(struct address_space
*mapping
, sector_t block
)
385 struct inode
*inode
= mapping
->host
;
387 mlog_entry("(block = %llu)\n", (unsigned long long)block
);
389 /* We don't need to lock journal system files, since they aren't
390 * accessed concurrently from multiple nodes.
392 if (!INODE_JOURNAL(inode
)) {
393 err
= ocfs2_meta_lock(inode
, NULL
, 0);
399 down_read(&OCFS2_I(inode
)->ip_alloc_sem
);
402 err
= ocfs2_extent_map_get_blocks(inode
, block
, &p_blkno
, NULL
, NULL
);
404 if (!INODE_JOURNAL(inode
)) {
405 up_read(&OCFS2_I(inode
)->ip_alloc_sem
);
406 ocfs2_meta_unlock(inode
, 0);
410 mlog(ML_ERROR
, "get_blocks() failed, block = %llu\n",
411 (unsigned long long)block
);
418 status
= err
? 0 : p_blkno
;
420 mlog_exit((int)status
);
426 * TODO: Make this into a generic get_blocks function.
428 * From do_direct_io in direct-io.c:
429 * "So what we do is to permit the ->get_blocks function to populate
430 * bh.b_size with the size of IO which is permitted at this offset and
433 * This function is called directly from get_more_blocks in direct-io.c.
435 * called like this: dio->get_blocks(dio->inode, fs_startblk,
436 * fs_count, map_bh, dio->rw == WRITE);
438 static int ocfs2_direct_IO_get_blocks(struct inode
*inode
, sector_t iblock
,
439 struct buffer_head
*bh_result
, int create
)
442 u64 p_blkno
, inode_blocks
;
444 unsigned int ext_flags
;
445 unsigned char blocksize_bits
= inode
->i_sb
->s_blocksize_bits
;
446 unsigned long max_blocks
= bh_result
->b_size
>> inode
->i_blkbits
;
448 /* This function won't even be called if the request isn't all
449 * nicely aligned and of the right size, so there's no need
450 * for us to check any of that. */
452 inode_blocks
= ocfs2_blocks_for_bytes(inode
->i_sb
, i_size_read(inode
));
455 * Any write past EOF is not allowed because we'd be extending.
457 if (create
&& (iblock
+ max_blocks
) > inode_blocks
) {
462 /* This figures out the size of the next contiguous block, and
463 * our logical offset */
464 ret
= ocfs2_extent_map_get_blocks(inode
, iblock
, &p_blkno
,
465 &contig_blocks
, &ext_flags
);
467 mlog(ML_ERROR
, "get_blocks() failed iblock=%llu\n",
468 (unsigned long long)iblock
);
473 if (!ocfs2_sparse_alloc(OCFS2_SB(inode
->i_sb
)) && !p_blkno
) {
474 ocfs2_error(inode
->i_sb
,
475 "Inode %llu has a hole at block %llu\n",
476 (unsigned long long)OCFS2_I(inode
)->ip_blkno
,
477 (unsigned long long)iblock
);
483 * get_more_blocks() expects us to describe a hole by clearing
484 * the mapped bit on bh_result().
486 * Consider an unwritten extent as a hole.
488 if (p_blkno
&& !(ext_flags
& OCFS2_EXT_UNWRITTEN
))
489 map_bh(bh_result
, inode
->i_sb
, p_blkno
);
492 * ocfs2_prepare_inode_for_write() should have caught
493 * the case where we'd be filling a hole and triggered
494 * a buffered write instead.
502 clear_buffer_mapped(bh_result
);
505 /* make sure we don't map more than max_blocks blocks here as
506 that's all the kernel will handle at this point. */
507 if (max_blocks
< contig_blocks
)
508 contig_blocks
= max_blocks
;
509 bh_result
->b_size
= contig_blocks
<< blocksize_bits
;
515 * ocfs2_dio_end_io is called by the dio core when a dio is finished. We're
516 * particularly interested in the aio/dio case. Like the core uses
517 * i_alloc_sem, we use the rw_lock DLM lock to protect io on one node from
518 * truncation on another.
520 static void ocfs2_dio_end_io(struct kiocb
*iocb
,
525 struct inode
*inode
= iocb
->ki_filp
->f_path
.dentry
->d_inode
;
527 /* this io's submitter should not have unlocked this before we could */
528 BUG_ON(!ocfs2_iocb_is_rw_locked(iocb
));
529 ocfs2_iocb_clear_rw_locked(iocb
);
530 up_read(&inode
->i_alloc_sem
);
531 ocfs2_rw_unlock(inode
, 0);
535 * ocfs2_invalidatepage() and ocfs2_releasepage() are shamelessly stolen
536 * from ext3. PageChecked() bits have been removed as OCFS2 does not
537 * do journalled data.
539 static void ocfs2_invalidatepage(struct page
*page
, unsigned long offset
)
541 journal_t
*journal
= OCFS2_SB(page
->mapping
->host
->i_sb
)->journal
->j_journal
;
543 journal_invalidatepage(journal
, page
, offset
);
546 static int ocfs2_releasepage(struct page
*page
, gfp_t wait
)
548 journal_t
*journal
= OCFS2_SB(page
->mapping
->host
->i_sb
)->journal
->j_journal
;
550 if (!page_has_buffers(page
))
552 return journal_try_to_free_buffers(journal
, page
, wait
);
555 static ssize_t
ocfs2_direct_IO(int rw
,
557 const struct iovec
*iov
,
559 unsigned long nr_segs
)
561 struct file
*file
= iocb
->ki_filp
;
562 struct inode
*inode
= file
->f_path
.dentry
->d_inode
->i_mapping
->host
;
567 if (!ocfs2_sparse_alloc(OCFS2_SB(inode
->i_sb
))) {
569 * We get PR data locks even for O_DIRECT. This
570 * allows concurrent O_DIRECT I/O but doesn't let
571 * O_DIRECT with extending and buffered zeroing writes
572 * race. If they did race then the buffered zeroing
573 * could be written back after the O_DIRECT I/O. It's
574 * one thing to tell people not to mix buffered and
575 * O_DIRECT writes, but expecting them to understand
576 * that file extension is also an implicit buffered
577 * write is too much. By getting the PR we force
578 * writeback of the buffered zeroing before
581 ret
= ocfs2_data_lock(inode
, 0);
586 ocfs2_data_unlock(inode
, 0);
589 ret
= blockdev_direct_IO_no_locking(rw
, iocb
, inode
,
590 inode
->i_sb
->s_bdev
, iov
, offset
,
592 ocfs2_direct_IO_get_blocks
,
599 static void ocfs2_figure_cluster_boundaries(struct ocfs2_super
*osb
,
604 unsigned int cluster_start
= 0, cluster_end
= PAGE_CACHE_SIZE
;
606 if (unlikely(PAGE_CACHE_SHIFT
> osb
->s_clustersize_bits
)) {
609 cpp
= 1 << (PAGE_CACHE_SHIFT
- osb
->s_clustersize_bits
);
611 cluster_start
= cpos
% cpp
;
612 cluster_start
= cluster_start
<< osb
->s_clustersize_bits
;
614 cluster_end
= cluster_start
+ osb
->s_clustersize
;
617 BUG_ON(cluster_start
> PAGE_SIZE
);
618 BUG_ON(cluster_end
> PAGE_SIZE
);
621 *start
= cluster_start
;
627 * 'from' and 'to' are the region in the page to avoid zeroing.
629 * If pagesize > clustersize, this function will avoid zeroing outside
630 * of the cluster boundary.
632 * from == to == 0 is code for "zero the entire cluster region"
634 static void ocfs2_clear_page_regions(struct page
*page
,
635 struct ocfs2_super
*osb
, u32 cpos
,
636 unsigned from
, unsigned to
)
639 unsigned int cluster_start
, cluster_end
;
641 ocfs2_figure_cluster_boundaries(osb
, cpos
, &cluster_start
, &cluster_end
);
643 kaddr
= kmap_atomic(page
, KM_USER0
);
646 if (from
> cluster_start
)
647 memset(kaddr
+ cluster_start
, 0, from
- cluster_start
);
648 if (to
< cluster_end
)
649 memset(kaddr
+ to
, 0, cluster_end
- to
);
651 memset(kaddr
+ cluster_start
, 0, cluster_end
- cluster_start
);
654 kunmap_atomic(kaddr
, KM_USER0
);
658 * Some of this taken from block_prepare_write(). We already have our
659 * mapping by now though, and the entire write will be allocating or
660 * it won't, so not much need to use BH_New.
662 * This will also skip zeroing, which is handled externally.
664 int ocfs2_map_page_blocks(struct page
*page
, u64
*p_blkno
,
665 struct inode
*inode
, unsigned int from
,
666 unsigned int to
, int new)
669 struct buffer_head
*head
, *bh
, *wait
[2], **wait_bh
= wait
;
670 unsigned int block_end
, block_start
;
671 unsigned int bsize
= 1 << inode
->i_blkbits
;
673 if (!page_has_buffers(page
))
674 create_empty_buffers(page
, bsize
, 0);
676 head
= page_buffers(page
);
677 for (bh
= head
, block_start
= 0; bh
!= head
|| !block_start
;
678 bh
= bh
->b_this_page
, block_start
+= bsize
) {
679 block_end
= block_start
+ bsize
;
682 * Ignore blocks outside of our i/o range -
683 * they may belong to unallocated clusters.
685 if (block_start
>= to
|| block_end
<= from
) {
686 if (PageUptodate(page
))
687 set_buffer_uptodate(bh
);
692 * For an allocating write with cluster size >= page
693 * size, we always write the entire page.
697 clear_buffer_new(bh
);
699 if (!buffer_mapped(bh
)) {
700 map_bh(bh
, inode
->i_sb
, *p_blkno
);
701 unmap_underlying_metadata(bh
->b_bdev
, bh
->b_blocknr
);
704 if (PageUptodate(page
)) {
705 if (!buffer_uptodate(bh
))
706 set_buffer_uptodate(bh
);
707 } else if (!buffer_uptodate(bh
) && !buffer_delay(bh
) &&
708 (block_start
< from
|| block_end
> to
)) {
709 ll_rw_block(READ
, 1, &bh
);
713 *p_blkno
= *p_blkno
+ 1;
717 * If we issued read requests - let them complete.
719 while(wait_bh
> wait
) {
720 wait_on_buffer(*--wait_bh
);
721 if (!buffer_uptodate(*wait_bh
))
725 if (ret
== 0 || !new)
729 * If we get -EIO above, zero out any newly allocated blocks
730 * to avoid exposing stale data.
737 block_end
= block_start
+ bsize
;
738 if (block_end
<= from
)
740 if (block_start
>= to
)
743 kaddr
= kmap_atomic(page
, KM_USER0
);
744 memset(kaddr
+block_start
, 0, bh
->b_size
);
745 flush_dcache_page(page
);
746 kunmap_atomic(kaddr
, KM_USER0
);
747 set_buffer_uptodate(bh
);
748 mark_buffer_dirty(bh
);
751 block_start
= block_end
;
752 bh
= bh
->b_this_page
;
753 } while (bh
!= head
);
759 * This will copy user data from the buffer page in the splice
762 * For now, we ignore SPLICE_F_MOVE as that would require some extra
763 * communication out all the way to ocfs2_write().
765 int ocfs2_map_and_write_splice_data(struct inode
*inode
,
766 struct ocfs2_write_ctxt
*wc
, u64
*p_blkno
,
767 unsigned int *ret_from
, unsigned int *ret_to
)
770 unsigned int to
, from
, cluster_start
, cluster_end
;
772 struct ocfs2_splice_write_priv
*sp
= wc
->w_private
;
773 struct pipe_buffer
*buf
= sp
->s_buf
;
774 unsigned long bytes
, src_from
;
775 struct ocfs2_super
*osb
= OCFS2_SB(inode
->i_sb
);
777 ocfs2_figure_cluster_boundaries(osb
, wc
->w_cpos
, &cluster_start
,
781 src_from
= sp
->s_buf_offset
;
784 if (wc
->w_large_pages
) {
786 * For cluster size < page size, we have to
787 * calculate pos within the cluster and obey
788 * the rightmost boundary.
790 bytes
= min(bytes
, (unsigned long)(osb
->s_clustersize
791 - (wc
->w_pos
& (osb
->s_clustersize
- 1))));
795 if (wc
->w_this_page_new
)
796 ret
= ocfs2_map_page_blocks(wc
->w_this_page
, p_blkno
, inode
,
797 cluster_start
, cluster_end
, 1);
799 ret
= ocfs2_map_page_blocks(wc
->w_this_page
, p_blkno
, inode
,
806 BUG_ON(from
> PAGE_CACHE_SIZE
);
807 BUG_ON(to
> PAGE_CACHE_SIZE
);
808 BUG_ON(from
> osb
->s_clustersize
);
809 BUG_ON(to
> osb
->s_clustersize
);
811 src
= buf
->ops
->map(sp
->s_pipe
, buf
, 1);
812 dst
= kmap_atomic(wc
->w_this_page
, KM_USER1
);
813 memcpy(dst
+ from
, src
+ src_from
, bytes
);
814 kunmap_atomic(wc
->w_this_page
, KM_USER1
);
815 buf
->ops
->unmap(sp
->s_pipe
, buf
, src
);
817 wc
->w_finished_copy
= 1;
823 return bytes
? (unsigned int)bytes
: ret
;
827 * This will copy user data from the iovec in the buffered write
830 int ocfs2_map_and_write_user_data(struct inode
*inode
,
831 struct ocfs2_write_ctxt
*wc
, u64
*p_blkno
,
832 unsigned int *ret_from
, unsigned int *ret_to
)
835 unsigned int to
, from
, cluster_start
, cluster_end
;
836 unsigned long bytes
, src_from
;
838 struct ocfs2_buffered_write_priv
*bp
= wc
->w_private
;
839 const struct iovec
*cur_iov
= bp
->b_cur_iov
;
841 struct ocfs2_super
*osb
= OCFS2_SB(inode
->i_sb
);
843 ocfs2_figure_cluster_boundaries(osb
, wc
->w_cpos
, &cluster_start
,
846 buf
= cur_iov
->iov_base
+ bp
->b_cur_off
;
847 src_from
= (unsigned long)buf
& ~PAGE_CACHE_MASK
;
849 from
= wc
->w_pos
& (PAGE_CACHE_SIZE
- 1);
852 * This is a lot of comparisons, but it reads quite
853 * easily, which is important here.
855 /* Stay within the src page */
856 bytes
= PAGE_SIZE
- src_from
;
857 /* Stay within the vector */
859 (unsigned long)(cur_iov
->iov_len
- bp
->b_cur_off
));
860 /* Stay within count */
861 bytes
= min(bytes
, (unsigned long)wc
->w_count
);
863 * For clustersize > page size, just stay within
864 * target page, otherwise we have to calculate pos
865 * within the cluster and obey the rightmost
868 if (wc
->w_large_pages
) {
870 * For cluster size < page size, we have to
871 * calculate pos within the cluster and obey
872 * the rightmost boundary.
874 bytes
= min(bytes
, (unsigned long)(osb
->s_clustersize
875 - (wc
->w_pos
& (osb
->s_clustersize
- 1))));
878 * cluster size > page size is the most common
879 * case - we just stay within the target page
882 bytes
= min(bytes
, PAGE_CACHE_SIZE
- from
);
887 if (wc
->w_this_page_new
)
888 ret
= ocfs2_map_page_blocks(wc
->w_this_page
, p_blkno
, inode
,
889 cluster_start
, cluster_end
, 1);
891 ret
= ocfs2_map_page_blocks(wc
->w_this_page
, p_blkno
, inode
,
898 BUG_ON(from
> PAGE_CACHE_SIZE
);
899 BUG_ON(to
> PAGE_CACHE_SIZE
);
900 BUG_ON(from
> osb
->s_clustersize
);
901 BUG_ON(to
> osb
->s_clustersize
);
903 dst
= kmap(wc
->w_this_page
);
904 memcpy(dst
+ from
, bp
->b_src_buf
+ src_from
, bytes
);
905 kunmap(wc
->w_this_page
);
908 * XXX: This is slow, but simple. The caller of
909 * ocfs2_buffered_write_cluster() is responsible for
910 * passing through the iovecs, so it's difficult to
911 * predict what our next step is in here after our
912 * initial write. A future version should be pushing
913 * that iovec manipulation further down.
915 * By setting this, we indicate that a copy from user
916 * data was done, and subsequent calls for this
917 * cluster will skip copying more data.
919 wc
->w_finished_copy
= 1;
925 return bytes
? (unsigned int)bytes
: ret
;
929 * Map, fill and write a page to disk.
931 * The work of copying data is done via callback. Newly allocated
932 * pages which don't take user data will be zero'd (set 'new' to
933 * indicate an allocating write)
935 * Returns a negative error code or the number of bytes copied into
938 int ocfs2_write_data_page(struct inode
*inode
, handle_t
*handle
,
939 u64
*p_blkno
, struct page
*page
,
940 struct ocfs2_write_ctxt
*wc
, int new)
943 unsigned int from
= 0, to
= 0;
944 unsigned int cluster_start
, cluster_end
;
945 unsigned int zero_from
= 0, zero_to
= 0;
947 ocfs2_figure_cluster_boundaries(OCFS2_SB(inode
->i_sb
), wc
->w_cpos
,
948 &cluster_start
, &cluster_end
);
950 if ((wc
->w_pos
>> PAGE_CACHE_SHIFT
) == page
->index
951 && !wc
->w_finished_copy
) {
953 wc
->w_this_page
= page
;
954 wc
->w_this_page_new
= new;
955 ret
= wc
->w_write_data_page(inode
, wc
, p_blkno
, &from
, &to
);
966 from
= cluster_start
;
971 * If we haven't allocated the new page yet, we
972 * shouldn't be writing it out without copying user
973 * data. This is likely a math error from the caller.
977 from
= cluster_start
;
980 ret
= ocfs2_map_page_blocks(page
, p_blkno
, inode
,
981 cluster_start
, cluster_end
, 1);
989 * Parts of newly allocated pages need to be zero'd.
991 * Above, we have also rewritten 'to' and 'from' - as far as
992 * the rest of the function is concerned, the entire cluster
993 * range inside of a page needs to be written.
995 * We can skip this if the page is up to date - it's already
996 * been zero'd from being read in as a hole.
998 if (new && !PageUptodate(page
))
999 ocfs2_clear_page_regions(page
, OCFS2_SB(inode
->i_sb
),
1000 wc
->w_cpos
, zero_from
, zero_to
);
1002 flush_dcache_page(page
);
1004 if (ocfs2_should_order_data(inode
)) {
1005 ret
= walk_page_buffers(handle
,
1008 ocfs2_journal_dirty_data
);
1014 * We don't use generic_commit_write() because we need to
1015 * handle our own i_size update.
1017 ret
= block_commit_write(page
, from
, to
);
1022 return copied
? copied
: ret
;
1026 * Do the actual write of some data into an inode. Optionally allocate
1027 * in order to fulfill the write.
1029 * cpos is the logical cluster offset within the file to write at
1031 * 'phys' is the physical mapping of that offset. a 'phys' value of
1032 * zero indicates that allocation is required. In this case, data_ac
1033 * and meta_ac should be valid (meta_ac can be null if metadata
1034 * allocation isn't required).
1036 static ssize_t
ocfs2_write(struct file
*file
, u32 phys
, handle_t
*handle
,
1037 struct buffer_head
*di_bh
,
1038 struct ocfs2_alloc_context
*data_ac
,
1039 struct ocfs2_alloc_context
*meta_ac
,
1040 struct ocfs2_write_ctxt
*wc
)
1042 int ret
, i
, numpages
= 1, new;
1043 unsigned int copied
= 0;
1045 u64 v_blkno
, p_blkno
;
1046 struct address_space
*mapping
= file
->f_mapping
;
1047 struct inode
*inode
= mapping
->host
;
1048 unsigned long index
, start
;
1049 struct page
**cpages
;
1051 new = phys
== 0 ? 1 : 0;
1054 * Figure out how many pages we'll be manipulating here. For
1055 * non allocating write, we just change the one
1056 * page. Otherwise, we'll need a whole clusters worth.
1059 numpages
= ocfs2_pages_per_cluster(inode
->i_sb
);
1061 cpages
= kzalloc(sizeof(*cpages
) * numpages
, GFP_NOFS
);
1069 * Fill our page array first. That way we've grabbed enough so
1070 * that we can zero and flush if we error after adding the
1074 start
= ocfs2_align_clusters_to_page_index(inode
->i_sb
,
1076 v_blkno
= ocfs2_clusters_to_blocks(inode
->i_sb
, wc
->w_cpos
);
1078 start
= wc
->w_pos
>> PAGE_CACHE_SHIFT
;
1079 v_blkno
= wc
->w_pos
>> inode
->i_sb
->s_blocksize_bits
;
1082 for(i
= 0; i
< numpages
; i
++) {
1085 cpages
[i
] = grab_cache_page(mapping
, index
);
1095 * This is safe to call with the page locks - it won't take
1096 * any additional semaphores or cluster locks.
1098 tmp_pos
= wc
->w_cpos
;
1099 ret
= ocfs2_do_extend_allocation(OCFS2_SB(inode
->i_sb
), inode
,
1100 &tmp_pos
, 1, di_bh
, handle
,
1101 data_ac
, meta_ac
, NULL
);
1103 * This shouldn't happen because we must have already
1104 * calculated the correct meta data allocation required. The
1105 * internal tree allocation code should know how to increase
1106 * transaction credits itself.
1108 * If need be, we could handle -EAGAIN for a
1109 * RESTART_TRANS here.
1111 mlog_bug_on_msg(ret
== -EAGAIN
,
1112 "Inode %llu: EAGAIN return during allocation.\n",
1113 (unsigned long long)OCFS2_I(inode
)->ip_blkno
);
1120 ret
= ocfs2_extent_map_get_blocks(inode
, v_blkno
, &p_blkno
, NULL
,
1125 * XXX: Should we go readonly here?
1132 BUG_ON(p_blkno
== 0);
1134 for(i
= 0; i
< numpages
; i
++) {
1135 ret
= ocfs2_write_data_page(inode
, handle
, &p_blkno
, cpages
[i
],
1146 for(i
= 0; i
< numpages
; i
++) {
1147 unlock_page(cpages
[i
]);
1148 mark_page_accessed(cpages
[i
]);
1149 page_cache_release(cpages
[i
]);
1153 return copied
? copied
: ret
;
1156 static void ocfs2_write_ctxt_init(struct ocfs2_write_ctxt
*wc
,
1157 struct ocfs2_super
*osb
, loff_t pos
,
1158 size_t count
, ocfs2_page_writer
*cb
,
1161 wc
->w_count
= count
;
1163 wc
->w_cpos
= wc
->w_pos
>> osb
->s_clustersize_bits
;
1164 wc
->w_finished_copy
= 0;
1166 if (unlikely(PAGE_CACHE_SHIFT
> osb
->s_clustersize_bits
))
1167 wc
->w_large_pages
= 1;
1169 wc
->w_large_pages
= 0;
1171 wc
->w_write_data_page
= cb
;
1172 wc
->w_private
= cb_priv
;
1176 * Write a cluster to an inode. The cluster may not be allocated yet,
1177 * in which case it will be. This only exists for buffered writes -
1178 * O_DIRECT takes a more "traditional" path through the kernel.
1180 * The caller is responsible for incrementing pos, written counts, etc
1182 * For file systems that don't support sparse files, pre-allocation
1183 * and page zeroing up until cpos should be done prior to this
1186 * Callers should be holding i_sem, and the rw cluster lock.
1188 * Returns the number of user bytes written, or less than zero for
1191 ssize_t
ocfs2_buffered_write_cluster(struct file
*file
, loff_t pos
,
1192 size_t count
, ocfs2_page_writer
*actor
,
1195 int ret
, credits
= OCFS2_INODE_UPDATE_CREDITS
;
1196 ssize_t written
= 0;
1198 struct inode
*inode
= file
->f_mapping
->host
;
1199 struct ocfs2_super
*osb
= OCFS2_SB(inode
->i_sb
);
1200 struct buffer_head
*di_bh
= NULL
;
1201 struct ocfs2_dinode
*di
;
1202 struct ocfs2_alloc_context
*data_ac
= NULL
;
1203 struct ocfs2_alloc_context
*meta_ac
= NULL
;
1205 struct ocfs2_write_ctxt wc
;
1207 ocfs2_write_ctxt_init(&wc
, osb
, pos
, count
, actor
, priv
);
1209 ret
= ocfs2_meta_lock(inode
, &di_bh
, 1);
1214 di
= (struct ocfs2_dinode
*)di_bh
->b_data
;
1217 * Take alloc sem here to prevent concurrent lookups. That way
1218 * the mapping, zeroing and tree manipulation within
1219 * ocfs2_write() will be safe against ->readpage(). This
1220 * should also serve to lock out allocation from a shared
1223 down_write(&OCFS2_I(inode
)->ip_alloc_sem
);
1225 ret
= ocfs2_get_clusters(inode
, wc
.w_cpos
, &phys
, NULL
, NULL
);
1231 /* phys == 0 means that allocation is required. */
1233 ret
= ocfs2_lock_allocators(inode
, di
, 1, &data_ac
, &meta_ac
);
1239 credits
= ocfs2_calc_extend_credits(inode
->i_sb
, di
, 1);
1242 ret
= ocfs2_data_lock(inode
, 1);
1248 handle
= ocfs2_start_trans(osb
, credits
);
1249 if (IS_ERR(handle
)) {
1250 ret
= PTR_ERR(handle
);
1255 written
= ocfs2_write(file
, phys
, handle
, di_bh
, data_ac
,
1263 ret
= ocfs2_journal_access(handle
, inode
, di_bh
,
1264 OCFS2_JOURNAL_ACCESS_WRITE
);
1271 if (pos
> inode
->i_size
) {
1272 i_size_write(inode
, pos
);
1273 mark_inode_dirty(inode
);
1275 inode
->i_blocks
= ocfs2_align_bytes_to_sectors((u64
)(i_size_read(inode
)));
1276 di
->i_size
= cpu_to_le64((u64
)i_size_read(inode
));
1277 inode
->i_mtime
= inode
->i_ctime
= CURRENT_TIME
;
1278 di
->i_mtime
= di
->i_ctime
= cpu_to_le64(inode
->i_mtime
.tv_sec
);
1279 di
->i_mtime_nsec
= di
->i_ctime_nsec
= cpu_to_le32(inode
->i_mtime
.tv_nsec
);
1281 ret
= ocfs2_journal_dirty(handle
, di_bh
);
1286 ocfs2_commit_trans(osb
, handle
);
1289 ocfs2_data_unlock(inode
, 1);
1292 up_write(&OCFS2_I(inode
)->ip_alloc_sem
);
1293 ocfs2_meta_unlock(inode
, 1);
1298 ocfs2_free_alloc_context(data_ac
);
1300 ocfs2_free_alloc_context(meta_ac
);
1302 return written
? written
: ret
;
1305 const struct address_space_operations ocfs2_aops
= {
1306 .readpage
= ocfs2_readpage
,
1307 .writepage
= ocfs2_writepage
,
1309 .sync_page
= block_sync_page
,
1310 .direct_IO
= ocfs2_direct_IO
,
1311 .invalidatepage
= ocfs2_invalidatepage
,
1312 .releasepage
= ocfs2_releasepage
,
1313 .migratepage
= buffer_migrate_page
,