2 * linux/fs/ext3/inode.c
4 * Copyright (C) 1992, 1993, 1994, 1995
5 * Remy Card (card@masi.ibp.fr)
6 * Laboratoire MASI - Institut Blaise Pascal
7 * Universite Pierre et Marie Curie (Paris VI)
11 * linux/fs/minix/inode.c
13 * Copyright (C) 1991, 1992 Linus Torvalds
15 * Goal-directed block allocation by Stephen Tweedie
16 * (sct@redhat.com), 1993, 1998
17 * Big-endian to little-endian byte-swapping/bitmaps by
18 * David S. Miller (davem@caip.rutgers.edu), 1995
19 * 64-bit file support on 64-bit platforms by Jakub Jelinek
20 * (jj@sunsite.ms.mff.cuni.cz)
22 * Assorted race fixes, rewrite of ext3_get_block() by Al Viro, 2000
25 #include <linux/module.h>
27 #include <linux/time.h>
28 #include <linux/ext3_jbd.h>
29 #include <linux/jbd.h>
30 #include <linux/smp_lock.h>
31 #include <linux/highuid.h>
32 #include <linux/pagemap.h>
33 #include <linux/quotaops.h>
34 #include <linux/string.h>
35 #include <linux/buffer_head.h>
36 #include <linux/writeback.h>
37 #include <linux/mpage.h>
38 #include <linux/uio.h>
42 static int ext3_writepage_trans_blocks(struct inode
*inode
);
45 * Test whether an inode is a fast symlink.
47 static int ext3_inode_is_fast_symlink(struct inode
*inode
)
49 int ea_blocks
= EXT3_I(inode
)->i_file_acl
?
50 (inode
->i_sb
->s_blocksize
>> 9) : 0;
52 return (S_ISLNK(inode
->i_mode
) && inode
->i_blocks
- ea_blocks
== 0);
56 * The ext3 forget function must perform a revoke if we are freeing data
57 * which has been journaled. Metadata (eg. indirect blocks) must be
58 * revoked in all cases.
60 * "bh" may be NULL: a metadata block may have been freed from memory
61 * but there may still be a record of it in the journal, and that record
62 * still needs to be revoked.
64 int ext3_forget(handle_t
*handle
, int is_metadata
, struct inode
*inode
,
65 struct buffer_head
*bh
, ext3_fsblk_t blocknr
)
71 BUFFER_TRACE(bh
, "enter");
73 jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, "
75 bh
, is_metadata
, inode
->i_mode
,
76 test_opt(inode
->i_sb
, DATA_FLAGS
));
78 /* Never use the revoke function if we are doing full data
79 * journaling: there is no need to, and a V1 superblock won't
80 * support it. Otherwise, only skip the revoke on un-journaled
83 if (test_opt(inode
->i_sb
, DATA_FLAGS
) == EXT3_MOUNT_JOURNAL_DATA
||
84 (!is_metadata
&& !ext3_should_journal_data(inode
))) {
86 BUFFER_TRACE(bh
, "call journal_forget");
87 return ext3_journal_forget(handle
, bh
);
93 * data!=journal && (is_metadata || should_journal_data(inode))
95 BUFFER_TRACE(bh
, "call ext3_journal_revoke");
96 err
= ext3_journal_revoke(handle
, blocknr
, bh
);
98 ext3_abort(inode
->i_sb
, __FUNCTION__
,
99 "error %d when attempting revoke", err
);
100 BUFFER_TRACE(bh
, "exit");
105 * Work out how many blocks we need to proceed with the next chunk of a
106 * truncate transaction.
108 static unsigned long blocks_for_truncate(struct inode
*inode
)
110 unsigned long needed
;
112 needed
= inode
->i_blocks
>> (inode
->i_sb
->s_blocksize_bits
- 9);
114 /* Give ourselves just enough room to cope with inodes in which
115 * i_blocks is corrupt: we've seen disk corruptions in the past
116 * which resulted in random data in an inode which looked enough
117 * like a regular file for ext3 to try to delete it. Things
118 * will go a bit crazy if that happens, but at least we should
119 * try not to panic the whole kernel. */
123 /* But we need to bound the transaction so we don't overflow the
125 if (needed
> EXT3_MAX_TRANS_DATA
)
126 needed
= EXT3_MAX_TRANS_DATA
;
128 return EXT3_DATA_TRANS_BLOCKS(inode
->i_sb
) + needed
;
132 * Truncate transactions can be complex and absolutely huge. So we need to
133 * be able to restart the transaction at a conventient checkpoint to make
134 * sure we don't overflow the journal.
136 * start_transaction gets us a new handle for a truncate transaction,
137 * and extend_transaction tries to extend the existing one a bit. If
138 * extend fails, we need to propagate the failure up and restart the
139 * transaction in the top-level truncate loop. --sct
141 static handle_t
*start_transaction(struct inode
*inode
)
145 result
= ext3_journal_start(inode
, blocks_for_truncate(inode
));
149 ext3_std_error(inode
->i_sb
, PTR_ERR(result
));
154 * Try to extend this transaction for the purposes of truncation.
156 * Returns 0 if we managed to create more room. If we can't create more
157 * room, and the transaction must be restarted we return 1.
159 static int try_to_extend_transaction(handle_t
*handle
, struct inode
*inode
)
161 if (handle
->h_buffer_credits
> EXT3_RESERVE_TRANS_BLOCKS
)
163 if (!ext3_journal_extend(handle
, blocks_for_truncate(inode
)))
169 * Restart the transaction associated with *handle. This does a commit,
170 * so before we call here everything must be consistently dirtied against
173 static int ext3_journal_test_restart(handle_t
*handle
, struct inode
*inode
)
175 jbd_debug(2, "restarting handle %p\n", handle
);
176 return ext3_journal_restart(handle
, blocks_for_truncate(inode
));
180 * Called at the last iput() if i_nlink is zero.
182 void ext3_delete_inode (struct inode
* inode
)
186 truncate_inode_pages(&inode
->i_data
, 0);
188 if (is_bad_inode(inode
))
191 handle
= start_transaction(inode
);
192 if (IS_ERR(handle
)) {
194 * If we're going to skip the normal cleanup, we still need to
195 * make sure that the in-core orphan linked list is properly
198 ext3_orphan_del(NULL
, inode
);
206 ext3_truncate(inode
);
208 * Kill off the orphan record which ext3_truncate created.
209 * AKPM: I think this can be inside the above `if'.
210 * Note that ext3_orphan_del() has to be able to cope with the
211 * deletion of a non-existent orphan - this is because we don't
212 * know if ext3_truncate() actually created an orphan record.
213 * (Well, we could do this if we need to, but heck - it works)
215 ext3_orphan_del(handle
, inode
);
216 EXT3_I(inode
)->i_dtime
= get_seconds();
219 * One subtle ordering requirement: if anything has gone wrong
220 * (transaction abort, IO errors, whatever), then we can still
221 * do these next steps (the fs will already have been marked as
222 * having errors), but we can't free the inode if the mark_dirty
225 if (ext3_mark_inode_dirty(handle
, inode
))
226 /* If that failed, just do the required in-core inode clear. */
229 ext3_free_inode(handle
, inode
);
230 ext3_journal_stop(handle
);
233 clear_inode(inode
); /* We must guarantee clearing of inode... */
239 struct buffer_head
*bh
;
242 static inline void add_chain(Indirect
*p
, struct buffer_head
*bh
, __le32
*v
)
244 p
->key
= *(p
->p
= v
);
248 static int verify_chain(Indirect
*from
, Indirect
*to
)
250 while (from
<= to
&& from
->key
== *from
->p
)
256 * ext3_block_to_path - parse the block number into array of offsets
257 * @inode: inode in question (we are only interested in its superblock)
258 * @i_block: block number to be parsed
259 * @offsets: array to store the offsets in
260 * @boundary: set this non-zero if the referred-to block is likely to be
261 * followed (on disk) by an indirect block.
263 * To store the locations of file's data ext3 uses a data structure common
264 * for UNIX filesystems - tree of pointers anchored in the inode, with
265 * data blocks at leaves and indirect blocks in intermediate nodes.
266 * This function translates the block number into path in that tree -
267 * return value is the path length and @offsets[n] is the offset of
268 * pointer to (n+1)th node in the nth one. If @block is out of range
269 * (negative or too large) warning is printed and zero returned.
271 * Note: function doesn't find node addresses, so no IO is needed. All
272 * we need to know is the capacity of indirect blocks (taken from the
277 * Portability note: the last comparison (check that we fit into triple
278 * indirect block) is spelled differently, because otherwise on an
279 * architecture with 32-bit longs and 8Kb pages we might get into trouble
280 * if our filesystem had 8Kb blocks. We might use long long, but that would
281 * kill us on x86. Oh, well, at least the sign propagation does not matter -
282 * i_block would have to be negative in the very beginning, so we would not
286 static int ext3_block_to_path(struct inode
*inode
,
287 long i_block
, int offsets
[4], int *boundary
)
289 int ptrs
= EXT3_ADDR_PER_BLOCK(inode
->i_sb
);
290 int ptrs_bits
= EXT3_ADDR_PER_BLOCK_BITS(inode
->i_sb
);
291 const long direct_blocks
= EXT3_NDIR_BLOCKS
,
292 indirect_blocks
= ptrs
,
293 double_blocks
= (1 << (ptrs_bits
* 2));
298 ext3_warning (inode
->i_sb
, "ext3_block_to_path", "block < 0");
299 } else if (i_block
< direct_blocks
) {
300 offsets
[n
++] = i_block
;
301 final
= direct_blocks
;
302 } else if ( (i_block
-= direct_blocks
) < indirect_blocks
) {
303 offsets
[n
++] = EXT3_IND_BLOCK
;
304 offsets
[n
++] = i_block
;
306 } else if ((i_block
-= indirect_blocks
) < double_blocks
) {
307 offsets
[n
++] = EXT3_DIND_BLOCK
;
308 offsets
[n
++] = i_block
>> ptrs_bits
;
309 offsets
[n
++] = i_block
& (ptrs
- 1);
311 } else if (((i_block
-= double_blocks
) >> (ptrs_bits
* 2)) < ptrs
) {
312 offsets
[n
++] = EXT3_TIND_BLOCK
;
313 offsets
[n
++] = i_block
>> (ptrs_bits
* 2);
314 offsets
[n
++] = (i_block
>> ptrs_bits
) & (ptrs
- 1);
315 offsets
[n
++] = i_block
& (ptrs
- 1);
318 ext3_warning(inode
->i_sb
, "ext3_block_to_path", "block > big");
321 *boundary
= final
- 1 - (i_block
& (ptrs
- 1));
326 * ext3_get_branch - read the chain of indirect blocks leading to data
327 * @inode: inode in question
328 * @depth: depth of the chain (1 - direct pointer, etc.)
329 * @offsets: offsets of pointers in inode/indirect blocks
330 * @chain: place to store the result
331 * @err: here we store the error value
333 * Function fills the array of triples <key, p, bh> and returns %NULL
334 * if everything went OK or the pointer to the last filled triple
335 * (incomplete one) otherwise. Upon the return chain[i].key contains
336 * the number of (i+1)-th block in the chain (as it is stored in memory,
337 * i.e. little-endian 32-bit), chain[i].p contains the address of that
338 * number (it points into struct inode for i==0 and into the bh->b_data
339 * for i>0) and chain[i].bh points to the buffer_head of i-th indirect
340 * block for i>0 and NULL for i==0. In other words, it holds the block
341 * numbers of the chain, addresses they were taken from (and where we can
342 * verify that chain did not change) and buffer_heads hosting these
345 * Function stops when it stumbles upon zero pointer (absent block)
346 * (pointer to last triple returned, *@err == 0)
347 * or when it gets an IO error reading an indirect block
348 * (ditto, *@err == -EIO)
349 * or when it notices that chain had been changed while it was reading
350 * (ditto, *@err == -EAGAIN)
351 * or when it reads all @depth-1 indirect blocks successfully and finds
352 * the whole chain, all way to the data (returns %NULL, *err == 0).
354 static Indirect
*ext3_get_branch(struct inode
*inode
, int depth
, int *offsets
,
355 Indirect chain
[4], int *err
)
357 struct super_block
*sb
= inode
->i_sb
;
359 struct buffer_head
*bh
;
362 /* i_data is not going away, no lock needed */
363 add_chain (chain
, NULL
, EXT3_I(inode
)->i_data
+ *offsets
);
367 bh
= sb_bread(sb
, le32_to_cpu(p
->key
));
370 /* Reader: pointers */
371 if (!verify_chain(chain
, p
))
373 add_chain(++p
, bh
, (__le32
*)bh
->b_data
+ *++offsets
);
391 * ext3_find_near - find a place for allocation with sufficient locality
393 * @ind: descriptor of indirect block.
395 * This function returns the prefered place for block allocation.
396 * It is used when heuristic for sequential allocation fails.
398 * + if there is a block to the left of our position - allocate near it.
399 * + if pointer will live in indirect block - allocate near that block.
400 * + if pointer will live in inode - allocate in the same
403 * In the latter case we colour the starting block by the callers PID to
404 * prevent it from clashing with concurrent allocations for a different inode
405 * in the same block group. The PID is used here so that functionally related
406 * files will be close-by on-disk.
408 * Caller must make sure that @ind is valid and will stay that way.
410 static ext3_fsblk_t
ext3_find_near(struct inode
*inode
, Indirect
*ind
)
412 struct ext3_inode_info
*ei
= EXT3_I(inode
);
413 __le32
*start
= ind
->bh
? (__le32
*) ind
->bh
->b_data
: ei
->i_data
;
415 ext3_fsblk_t bg_start
;
416 ext3_grpblk_t colour
;
418 /* Try to find previous block */
419 for (p
= ind
->p
- 1; p
>= start
; p
--) {
421 return le32_to_cpu(*p
);
424 /* No such thing, so let's try location of indirect block */
426 return ind
->bh
->b_blocknr
;
429 * It is going to be referred to from the inode itself? OK, just put it
430 * into the same cylinder group then.
432 bg_start
= ext3_group_first_block_no(inode
->i_sb
, ei
->i_block_group
);
433 colour
= (current
->pid
% 16) *
434 (EXT3_BLOCKS_PER_GROUP(inode
->i_sb
) / 16);
435 return bg_start
+ colour
;
439 * ext3_find_goal - find a prefered place for allocation.
441 * @block: block we want
442 * @chain: chain of indirect blocks
443 * @partial: pointer to the last triple within a chain
444 * @goal: place to store the result.
446 * Normally this function find the prefered place for block allocation,
447 * stores it in *@goal and returns zero.
450 static ext3_fsblk_t
ext3_find_goal(struct inode
*inode
, long block
,
451 Indirect chain
[4], Indirect
*partial
)
453 struct ext3_block_alloc_info
*block_i
;
455 block_i
= EXT3_I(inode
)->i_block_alloc_info
;
458 * try the heuristic for sequential allocation,
459 * failing that at least try to get decent locality.
461 if (block_i
&& (block
== block_i
->last_alloc_logical_block
+ 1)
462 && (block_i
->last_alloc_physical_block
!= 0)) {
463 return block_i
->last_alloc_physical_block
+ 1;
466 return ext3_find_near(inode
, partial
);
470 * ext3_blks_to_allocate: Look up the block map and count the number
471 * of direct blocks need to be allocated for the given branch.
473 * @branch: chain of indirect blocks
474 * @k: number of blocks need for indirect blocks
475 * @blks: number of data blocks to be mapped.
476 * @blocks_to_boundary: the offset in the indirect block
478 * return the total number of blocks to be allocate, including the
479 * direct and indirect blocks.
481 static int ext3_blks_to_allocate(Indirect
*branch
, int k
, unsigned long blks
,
482 int blocks_to_boundary
)
484 unsigned long count
= 0;
487 * Simple case, [t,d]Indirect block(s) has not allocated yet
488 * then it's clear blocks on that path have not allocated
491 /* right now we don't handle cross boundary allocation */
492 if (blks
< blocks_to_boundary
+ 1)
495 count
+= blocks_to_boundary
+ 1;
500 while (count
< blks
&& count
<= blocks_to_boundary
&&
501 le32_to_cpu(*(branch
[0].p
+ count
)) == 0) {
508 * ext3_alloc_blocks: multiple allocate blocks needed for a branch
509 * @indirect_blks: the number of blocks need to allocate for indirect
512 * @new_blocks: on return it will store the new block numbers for
513 * the indirect blocks(if needed) and the first direct block,
514 * @blks: on return it will store the total number of allocated
517 static int ext3_alloc_blocks(handle_t
*handle
, struct inode
*inode
,
518 ext3_fsblk_t goal
, int indirect_blks
, int blks
,
519 ext3_fsblk_t new_blocks
[4], int *err
)
522 unsigned long count
= 0;
524 ext3_fsblk_t current_block
= 0;
528 * Here we try to allocate the requested multiple blocks at once,
529 * on a best-effort basis.
530 * To build a branch, we should allocate blocks for
531 * the indirect blocks(if not allocated yet), and at least
532 * the first direct block of this branch. That's the
533 * minimum number of blocks need to allocate(required)
535 target
= blks
+ indirect_blks
;
539 /* allocating blocks for indirect blocks and direct blocks */
540 current_block
= ext3_new_blocks(handle
,inode
,goal
,&count
,err
);
545 /* allocate blocks for indirect blocks */
546 while (index
< indirect_blks
&& count
) {
547 new_blocks
[index
++] = current_block
++;
555 /* save the new block number for the first direct block */
556 new_blocks
[index
] = current_block
;
558 /* total number of blocks allocated for direct blocks */
563 for (i
= 0; i
<index
; i
++)
564 ext3_free_blocks(handle
, inode
, new_blocks
[i
], 1);
569 * ext3_alloc_branch - allocate and set up a chain of blocks.
571 * @indirect_blks: number of allocated indirect blocks
572 * @blks: number of allocated direct blocks
573 * @offsets: offsets (in the blocks) to store the pointers to next.
574 * @branch: place to store the chain in.
576 * This function allocates blocks, zeroes out all but the last one,
577 * links them into chain and (if we are synchronous) writes them to disk.
578 * In other words, it prepares a branch that can be spliced onto the
579 * inode. It stores the information about that chain in the branch[], in
580 * the same format as ext3_get_branch() would do. We are calling it after
581 * we had read the existing part of chain and partial points to the last
582 * triple of that (one with zero ->key). Upon the exit we have the same
583 * picture as after the successful ext3_get_block(), except that in one
584 * place chain is disconnected - *branch->p is still zero (we did not
585 * set the last link), but branch->key contains the number that should
586 * be placed into *branch->p to fill that gap.
588 * If allocation fails we free all blocks we've allocated (and forget
589 * their buffer_heads) and return the error value the from failed
590 * ext3_alloc_block() (normally -ENOSPC). Otherwise we set the chain
591 * as described above and return 0.
593 static int ext3_alloc_branch(handle_t
*handle
, struct inode
*inode
,
594 int indirect_blks
, int *blks
, ext3_fsblk_t goal
,
595 int *offsets
, Indirect
*branch
)
597 int blocksize
= inode
->i_sb
->s_blocksize
;
600 struct buffer_head
*bh
;
602 ext3_fsblk_t new_blocks
[4];
603 ext3_fsblk_t current_block
;
605 num
= ext3_alloc_blocks(handle
, inode
, goal
, indirect_blks
,
606 *blks
, new_blocks
, &err
);
610 branch
[0].key
= cpu_to_le32(new_blocks
[0]);
612 * metadata blocks and data blocks are allocated.
614 for (n
= 1; n
<= indirect_blks
; n
++) {
616 * Get buffer_head for parent block, zero it out
617 * and set the pointer to new one, then send
620 bh
= sb_getblk(inode
->i_sb
, new_blocks
[n
-1]);
623 BUFFER_TRACE(bh
, "call get_create_access");
624 err
= ext3_journal_get_create_access(handle
, bh
);
631 memset(bh
->b_data
, 0, blocksize
);
632 branch
[n
].p
= (__le32
*) bh
->b_data
+ offsets
[n
];
633 branch
[n
].key
= cpu_to_le32(new_blocks
[n
]);
634 *branch
[n
].p
= branch
[n
].key
;
635 if ( n
== indirect_blks
) {
636 current_block
= new_blocks
[n
];
638 * End of chain, update the last new metablock of
639 * the chain to point to the new allocated
640 * data blocks numbers
642 for (i
=1; i
< num
; i
++)
643 *(branch
[n
].p
+ i
) = cpu_to_le32(++current_block
);
645 BUFFER_TRACE(bh
, "marking uptodate");
646 set_buffer_uptodate(bh
);
649 BUFFER_TRACE(bh
, "call ext3_journal_dirty_metadata");
650 err
= ext3_journal_dirty_metadata(handle
, bh
);
657 /* Allocation failed, free what we already allocated */
658 for (i
= 1; i
<= n
; i
++) {
659 BUFFER_TRACE(branch
[i
].bh
, "call journal_forget");
660 ext3_journal_forget(handle
, branch
[i
].bh
);
662 for (i
= 0; i
<indirect_blks
; i
++)
663 ext3_free_blocks(handle
, inode
, new_blocks
[i
], 1);
665 ext3_free_blocks(handle
, inode
, new_blocks
[i
], num
);
671 * ext3_splice_branch - splice the allocated branch onto inode.
673 * @block: (logical) number of block we are adding
674 * @chain: chain of indirect blocks (with a missing link - see
676 * @where: location of missing link
677 * @num: number of indirect blocks we are adding
678 * @blks: number of direct blocks we are adding
680 * This function fills the missing link and does all housekeeping needed in
681 * inode (->i_blocks, etc.). In case of success we end up with the full
682 * chain to new block and return 0.
684 static int ext3_splice_branch(handle_t
*handle
, struct inode
*inode
,
685 long block
, Indirect
*where
, int num
, int blks
)
689 struct ext3_block_alloc_info
*block_i
;
690 ext3_fsblk_t current_block
;
692 block_i
= EXT3_I(inode
)->i_block_alloc_info
;
694 * If we're splicing into a [td]indirect block (as opposed to the
695 * inode) then we need to get write access to the [td]indirect block
699 BUFFER_TRACE(where
->bh
, "get_write_access");
700 err
= ext3_journal_get_write_access(handle
, where
->bh
);
706 *where
->p
= where
->key
;
709 * Update the host buffer_head or inode to point to more just allocated
710 * direct blocks blocks
712 if (num
== 0 && blks
> 1) {
713 current_block
= le32_to_cpu(where
->key
) + 1;
714 for (i
= 1; i
< blks
; i
++)
715 *(where
->p
+ i
) = cpu_to_le32(current_block
++);
719 * update the most recently allocated logical & physical block
720 * in i_block_alloc_info, to assist find the proper goal block for next
724 block_i
->last_alloc_logical_block
= block
+ blks
- 1;
725 block_i
->last_alloc_physical_block
=
726 le32_to_cpu(where
[num
].key
) + blks
- 1;
729 /* We are done with atomic stuff, now do the rest of housekeeping */
731 inode
->i_ctime
= CURRENT_TIME_SEC
;
732 ext3_mark_inode_dirty(handle
, inode
);
734 /* had we spliced it onto indirect block? */
737 * If we spliced it onto an indirect block, we haven't
738 * altered the inode. Note however that if it is being spliced
739 * onto an indirect block at the very end of the file (the
740 * file is growing) then we *will* alter the inode to reflect
741 * the new i_size. But that is not done here - it is done in
742 * generic_commit_write->__mark_inode_dirty->ext3_dirty_inode.
744 jbd_debug(5, "splicing indirect only\n");
745 BUFFER_TRACE(where
->bh
, "call ext3_journal_dirty_metadata");
746 err
= ext3_journal_dirty_metadata(handle
, where
->bh
);
751 * OK, we spliced it into the inode itself on a direct block.
752 * Inode was dirtied above.
754 jbd_debug(5, "splicing direct\n");
759 for (i
= 1; i
<= num
; i
++) {
760 BUFFER_TRACE(where
[i
].bh
, "call journal_forget");
761 ext3_journal_forget(handle
, where
[i
].bh
);
762 ext3_free_blocks(handle
,inode
,le32_to_cpu(where
[i
-1].key
),1);
764 ext3_free_blocks(handle
, inode
, le32_to_cpu(where
[num
].key
), blks
);
770 * Allocation strategy is simple: if we have to allocate something, we will
771 * have to go the whole way to leaf. So let's do it before attaching anything
772 * to tree, set linkage between the newborn blocks, write them if sync is
773 * required, recheck the path, free and repeat if check fails, otherwise
774 * set the last missing link (that will protect us from any truncate-generated
775 * removals - all blocks on the path are immune now) and possibly force the
776 * write on the parent block.
777 * That has a nice additional property: no special recovery from the failed
778 * allocations is needed - we simply release blocks and do not touch anything
779 * reachable from inode.
781 * `handle' can be NULL if create == 0.
783 * The BKL may not be held on entry here. Be sure to take it early.
784 * return > 0, # of blocks mapped or allocated.
785 * return = 0, if plain lookup failed.
786 * return < 0, error case.
788 int ext3_get_blocks_handle(handle_t
*handle
, struct inode
*inode
,
789 sector_t iblock
, unsigned long maxblocks
,
790 struct buffer_head
*bh_result
,
791 int create
, int extend_disksize
)
799 int blocks_to_boundary
= 0;
801 struct ext3_inode_info
*ei
= EXT3_I(inode
);
803 ext3_fsblk_t first_block
= 0;
806 J_ASSERT(handle
!= NULL
|| create
== 0);
807 depth
= ext3_block_to_path(inode
,iblock
,offsets
,&blocks_to_boundary
);
812 partial
= ext3_get_branch(inode
, depth
, offsets
, chain
, &err
);
814 /* Simplest case - block found, no allocation needed */
816 first_block
= le32_to_cpu(chain
[depth
- 1].key
);
817 clear_buffer_new(bh_result
);
820 while (count
< maxblocks
&& count
<= blocks_to_boundary
) {
823 if (!verify_chain(chain
, partial
)) {
825 * Indirect block might be removed by
826 * truncate while we were reading it.
827 * Handling of that case: forget what we've
828 * got now. Flag the err as EAGAIN, so it
835 blk
= le32_to_cpu(*(chain
[depth
-1].p
+ count
));
837 if (blk
== first_block
+ count
)
846 /* Next simple case - plain lookup or failed read of indirect block */
847 if (!create
|| err
== -EIO
)
850 mutex_lock(&ei
->truncate_mutex
);
853 * If the indirect block is missing while we are reading
854 * the chain(ext3_get_branch() returns -EAGAIN err), or
855 * if the chain has been changed after we grab the semaphore,
856 * (either because another process truncated this branch, or
857 * another get_block allocated this branch) re-grab the chain to see if
858 * the request block has been allocated or not.
860 * Since we already block the truncate/other get_block
861 * at this point, we will have the current copy of the chain when we
862 * splice the branch into the tree.
864 if (err
== -EAGAIN
|| !verify_chain(chain
, partial
)) {
865 while (partial
> chain
) {
869 partial
= ext3_get_branch(inode
, depth
, offsets
, chain
, &err
);
872 mutex_unlock(&ei
->truncate_mutex
);
875 clear_buffer_new(bh_result
);
881 * Okay, we need to do block allocation. Lazily initialize the block
882 * allocation info here if necessary
884 if (S_ISREG(inode
->i_mode
) && (!ei
->i_block_alloc_info
))
885 ext3_init_block_alloc_info(inode
);
887 goal
= ext3_find_goal(inode
, iblock
, chain
, partial
);
889 /* the number of blocks need to allocate for [d,t]indirect blocks */
890 indirect_blks
= (chain
+ depth
) - partial
- 1;
893 * Next look up the indirect map to count the totoal number of
894 * direct blocks to allocate for this branch.
896 count
= ext3_blks_to_allocate(partial
, indirect_blks
,
897 maxblocks
, blocks_to_boundary
);
899 * Block out ext3_truncate while we alter the tree
901 err
= ext3_alloc_branch(handle
, inode
, indirect_blks
, &count
, goal
,
902 offsets
+ (partial
- chain
), partial
);
905 * The ext3_splice_branch call will free and forget any buffers
906 * on the new chain if there is a failure, but that risks using
907 * up transaction credits, especially for bitmaps where the
908 * credits cannot be returned. Can we handle this somehow? We
909 * may need to return -EAGAIN upwards in the worst case. --sct
912 err
= ext3_splice_branch(handle
, inode
, iblock
,
913 partial
, indirect_blks
, count
);
915 * i_disksize growing is protected by truncate_mutex. Don't forget to
916 * protect it if you're about to implement concurrent
917 * ext3_get_block() -bzzz
919 if (!err
&& extend_disksize
&& inode
->i_size
> ei
->i_disksize
)
920 ei
->i_disksize
= inode
->i_size
;
921 mutex_unlock(&ei
->truncate_mutex
);
925 set_buffer_new(bh_result
);
927 map_bh(bh_result
, inode
->i_sb
, le32_to_cpu(chain
[depth
-1].key
));
928 if (count
> blocks_to_boundary
)
929 set_buffer_boundary(bh_result
);
931 /* Clean up and exit */
932 partial
= chain
+ depth
- 1; /* the whole chain */
934 while (partial
> chain
) {
935 BUFFER_TRACE(partial
->bh
, "call brelse");
939 BUFFER_TRACE(bh_result
, "returned");
944 #define DIO_CREDITS (EXT3_RESERVE_TRANS_BLOCKS + 32)
946 static int ext3_get_block(struct inode
*inode
, sector_t iblock
,
947 struct buffer_head
*bh_result
, int create
)
949 handle_t
*handle
= journal_current_handle();
951 unsigned max_blocks
= bh_result
->b_size
>> inode
->i_blkbits
;
954 goto get_block
; /* A read */
957 goto get_block
; /* A single block get */
959 if (handle
->h_transaction
->t_state
== T_LOCKED
) {
961 * Huge direct-io writes can hold off commits for long
962 * periods of time. Let this commit run.
964 ext3_journal_stop(handle
);
965 handle
= ext3_journal_start(inode
, DIO_CREDITS
);
967 ret
= PTR_ERR(handle
);
971 if (handle
->h_buffer_credits
<= EXT3_RESERVE_TRANS_BLOCKS
) {
973 * Getting low on buffer credits...
975 ret
= ext3_journal_extend(handle
, DIO_CREDITS
);
978 * Couldn't extend the transaction. Start a new one.
980 ret
= ext3_journal_restart(handle
, DIO_CREDITS
);
986 ret
= ext3_get_blocks_handle(handle
, inode
, iblock
,
987 max_blocks
, bh_result
, create
, 0);
989 bh_result
->b_size
= (ret
<< inode
->i_blkbits
);
997 * `handle' can be NULL if create is zero
999 struct buffer_head
*ext3_getblk(handle_t
*handle
, struct inode
*inode
,
1000 long block
, int create
, int *errp
)
1002 struct buffer_head dummy
;
1005 J_ASSERT(handle
!= NULL
|| create
== 0);
1008 dummy
.b_blocknr
= -1000;
1009 buffer_trace_init(&dummy
.b_history
);
1010 err
= ext3_get_blocks_handle(handle
, inode
, block
, 1,
1013 * ext3_get_blocks_handle() returns number of blocks
1014 * mapped. 0 in case of a HOLE.
1022 if (!err
&& buffer_mapped(&dummy
)) {
1023 struct buffer_head
*bh
;
1024 bh
= sb_getblk(inode
->i_sb
, dummy
.b_blocknr
);
1029 if (buffer_new(&dummy
)) {
1030 J_ASSERT(create
!= 0);
1031 J_ASSERT(handle
!= 0);
1034 * Now that we do not always journal data, we should
1035 * keep in mind whether this should always journal the
1036 * new buffer as metadata. For now, regular file
1037 * writes use ext3_get_block instead, so it's not a
1041 BUFFER_TRACE(bh
, "call get_create_access");
1042 fatal
= ext3_journal_get_create_access(handle
, bh
);
1043 if (!fatal
&& !buffer_uptodate(bh
)) {
1044 memset(bh
->b_data
,0,inode
->i_sb
->s_blocksize
);
1045 set_buffer_uptodate(bh
);
1048 BUFFER_TRACE(bh
, "call ext3_journal_dirty_metadata");
1049 err
= ext3_journal_dirty_metadata(handle
, bh
);
1053 BUFFER_TRACE(bh
, "not a new buffer");
1066 struct buffer_head
*ext3_bread(handle_t
*handle
, struct inode
*inode
,
1067 int block
, int create
, int *err
)
1069 struct buffer_head
* bh
;
1071 bh
= ext3_getblk(handle
, inode
, block
, create
, err
);
1074 if (buffer_uptodate(bh
))
1076 ll_rw_block(READ
, 1, &bh
);
1078 if (buffer_uptodate(bh
))
1085 static int walk_page_buffers( handle_t
*handle
,
1086 struct buffer_head
*head
,
1090 int (*fn
)( handle_t
*handle
,
1091 struct buffer_head
*bh
))
1093 struct buffer_head
*bh
;
1094 unsigned block_start
, block_end
;
1095 unsigned blocksize
= head
->b_size
;
1097 struct buffer_head
*next
;
1099 for ( bh
= head
, block_start
= 0;
1100 ret
== 0 && (bh
!= head
|| !block_start
);
1101 block_start
= block_end
, bh
= next
)
1103 next
= bh
->b_this_page
;
1104 block_end
= block_start
+ blocksize
;
1105 if (block_end
<= from
|| block_start
>= to
) {
1106 if (partial
&& !buffer_uptodate(bh
))
1110 err
= (*fn
)(handle
, bh
);
1118 * To preserve ordering, it is essential that the hole instantiation and
1119 * the data write be encapsulated in a single transaction. We cannot
1120 * close off a transaction and start a new one between the ext3_get_block()
1121 * and the commit_write(). So doing the journal_start at the start of
1122 * prepare_write() is the right place.
1124 * Also, this function can nest inside ext3_writepage() ->
1125 * block_write_full_page(). In that case, we *know* that ext3_writepage()
1126 * has generated enough buffer credits to do the whole page. So we won't
1127 * block on the journal in that case, which is good, because the caller may
1130 * By accident, ext3 can be reentered when a transaction is open via
1131 * quota file writes. If we were to commit the transaction while thus
1132 * reentered, there can be a deadlock - we would be holding a quota
1133 * lock, and the commit would never complete if another thread had a
1134 * transaction open and was blocking on the quota lock - a ranking
1137 * So what we do is to rely on the fact that journal_stop/journal_start
1138 * will _not_ run commit under these circumstances because handle->h_ref
1139 * is elevated. We'll still have enough credits for the tiny quotafile
1142 static int do_journal_get_write_access(handle_t
*handle
,
1143 struct buffer_head
*bh
)
1145 if (!buffer_mapped(bh
) || buffer_freed(bh
))
1147 return ext3_journal_get_write_access(handle
, bh
);
1150 static int ext3_prepare_write(struct file
*file
, struct page
*page
,
1151 unsigned from
, unsigned to
)
1153 struct inode
*inode
= page
->mapping
->host
;
1154 int ret
, needed_blocks
= ext3_writepage_trans_blocks(inode
);
1159 handle
= ext3_journal_start(inode
, needed_blocks
);
1160 if (IS_ERR(handle
)) {
1161 ret
= PTR_ERR(handle
);
1164 if (test_opt(inode
->i_sb
, NOBH
) && ext3_should_writeback_data(inode
))
1165 ret
= nobh_prepare_write(page
, from
, to
, ext3_get_block
);
1167 ret
= block_prepare_write(page
, from
, to
, ext3_get_block
);
1169 goto prepare_write_failed
;
1171 if (ext3_should_journal_data(inode
)) {
1172 ret
= walk_page_buffers(handle
, page_buffers(page
),
1173 from
, to
, NULL
, do_journal_get_write_access
);
1175 prepare_write_failed
:
1177 ext3_journal_stop(handle
);
1178 if (ret
== -ENOSPC
&& ext3_should_retry_alloc(inode
->i_sb
, &retries
))
1184 int ext3_journal_dirty_data(handle_t
*handle
, struct buffer_head
*bh
)
1186 int err
= journal_dirty_data(handle
, bh
);
1188 ext3_journal_abort_handle(__FUNCTION__
, __FUNCTION__
,
1193 /* For commit_write() in data=journal mode */
1194 static int commit_write_fn(handle_t
*handle
, struct buffer_head
*bh
)
1196 if (!buffer_mapped(bh
) || buffer_freed(bh
))
1198 set_buffer_uptodate(bh
);
1199 return ext3_journal_dirty_metadata(handle
, bh
);
1203 * We need to pick up the new inode size which generic_commit_write gave us
1204 * `file' can be NULL - eg, when called from page_symlink().
1206 * ext3 never places buffers on inode->i_mapping->private_list. metadata
1207 * buffers are managed internally.
1209 static int ext3_ordered_commit_write(struct file
*file
, struct page
*page
,
1210 unsigned from
, unsigned to
)
1212 handle_t
*handle
= ext3_journal_current_handle();
1213 struct inode
*inode
= page
->mapping
->host
;
1216 ret
= walk_page_buffers(handle
, page_buffers(page
),
1217 from
, to
, NULL
, ext3_journal_dirty_data
);
1221 * generic_commit_write() will run mark_inode_dirty() if i_size
1222 * changes. So let's piggyback the i_disksize mark_inode_dirty
1227 new_i_size
= ((loff_t
)page
->index
<< PAGE_CACHE_SHIFT
) + to
;
1228 if (new_i_size
> EXT3_I(inode
)->i_disksize
)
1229 EXT3_I(inode
)->i_disksize
= new_i_size
;
1230 ret
= generic_commit_write(file
, page
, from
, to
);
1232 ret2
= ext3_journal_stop(handle
);
1238 static int ext3_writeback_commit_write(struct file
*file
, struct page
*page
,
1239 unsigned from
, unsigned to
)
1241 handle_t
*handle
= ext3_journal_current_handle();
1242 struct inode
*inode
= page
->mapping
->host
;
1246 new_i_size
= ((loff_t
)page
->index
<< PAGE_CACHE_SHIFT
) + to
;
1247 if (new_i_size
> EXT3_I(inode
)->i_disksize
)
1248 EXT3_I(inode
)->i_disksize
= new_i_size
;
1250 if (test_opt(inode
->i_sb
, NOBH
) && ext3_should_writeback_data(inode
))
1251 ret
= nobh_commit_write(file
, page
, from
, to
);
1253 ret
= generic_commit_write(file
, page
, from
, to
);
1255 ret2
= ext3_journal_stop(handle
);
1261 static int ext3_journalled_commit_write(struct file
*file
,
1262 struct page
*page
, unsigned from
, unsigned to
)
1264 handle_t
*handle
= ext3_journal_current_handle();
1265 struct inode
*inode
= page
->mapping
->host
;
1271 * Here we duplicate the generic_commit_write() functionality
1273 pos
= ((loff_t
)page
->index
<< PAGE_CACHE_SHIFT
) + to
;
1275 ret
= walk_page_buffers(handle
, page_buffers(page
), from
,
1276 to
, &partial
, commit_write_fn
);
1278 SetPageUptodate(page
);
1279 if (pos
> inode
->i_size
)
1280 i_size_write(inode
, pos
);
1281 EXT3_I(inode
)->i_state
|= EXT3_STATE_JDATA
;
1282 if (inode
->i_size
> EXT3_I(inode
)->i_disksize
) {
1283 EXT3_I(inode
)->i_disksize
= inode
->i_size
;
1284 ret2
= ext3_mark_inode_dirty(handle
, inode
);
1288 ret2
= ext3_journal_stop(handle
);
1295 * bmap() is special. It gets used by applications such as lilo and by
1296 * the swapper to find the on-disk block of a specific piece of data.
1298 * Naturally, this is dangerous if the block concerned is still in the
1299 * journal. If somebody makes a swapfile on an ext3 data-journaling
1300 * filesystem and enables swap, then they may get a nasty shock when the
1301 * data getting swapped to that swapfile suddenly gets overwritten by
1302 * the original zero's written out previously to the journal and
1303 * awaiting writeback in the kernel's buffer cache.
1305 * So, if we see any bmap calls here on a modified, data-journaled file,
1306 * take extra steps to flush any blocks which might be in the cache.
1308 static sector_t
ext3_bmap(struct address_space
*mapping
, sector_t block
)
1310 struct inode
*inode
= mapping
->host
;
1314 if (EXT3_I(inode
)->i_state
& EXT3_STATE_JDATA
) {
1316 * This is a REALLY heavyweight approach, but the use of
1317 * bmap on dirty files is expected to be extremely rare:
1318 * only if we run lilo or swapon on a freshly made file
1319 * do we expect this to happen.
1321 * (bmap requires CAP_SYS_RAWIO so this does not
1322 * represent an unprivileged user DOS attack --- we'd be
1323 * in trouble if mortal users could trigger this path at
1326 * NB. EXT3_STATE_JDATA is not set on files other than
1327 * regular files. If somebody wants to bmap a directory
1328 * or symlink and gets confused because the buffer
1329 * hasn't yet been flushed to disk, they deserve
1330 * everything they get.
1333 EXT3_I(inode
)->i_state
&= ~EXT3_STATE_JDATA
;
1334 journal
= EXT3_JOURNAL(inode
);
1335 journal_lock_updates(journal
);
1336 err
= journal_flush(journal
);
1337 journal_unlock_updates(journal
);
1343 return generic_block_bmap(mapping
,block
,ext3_get_block
);
1346 static int bget_one(handle_t
*handle
, struct buffer_head
*bh
)
1352 static int bput_one(handle_t
*handle
, struct buffer_head
*bh
)
1358 static int journal_dirty_data_fn(handle_t
*handle
, struct buffer_head
*bh
)
1360 if (buffer_mapped(bh
))
1361 return ext3_journal_dirty_data(handle
, bh
);
1366 * Note that we always start a transaction even if we're not journalling
1367 * data. This is to preserve ordering: any hole instantiation within
1368 * __block_write_full_page -> ext3_get_block() should be journalled
1369 * along with the data so we don't crash and then get metadata which
1370 * refers to old data.
1372 * In all journalling modes block_write_full_page() will start the I/O.
1376 * ext3_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() ->
1381 * ext3_file_write() -> generic_file_write() -> __alloc_pages() -> ...
1383 * Same applies to ext3_get_block(). We will deadlock on various things like
1384 * lock_journal and i_truncate_mutex.
1386 * Setting PF_MEMALLOC here doesn't work - too many internal memory
1389 * 16May01: If we're reentered then journal_current_handle() will be
1390 * non-zero. We simply *return*.
1392 * 1 July 2001: @@@ FIXME:
1393 * In journalled data mode, a data buffer may be metadata against the
1394 * current transaction. But the same file is part of a shared mapping
1395 * and someone does a writepage() on it.
1397 * We will move the buffer onto the async_data list, but *after* it has
1398 * been dirtied. So there's a small window where we have dirty data on
1401 * Note that this only applies to the last partial page in the file. The
1402 * bit which block_write_full_page() uses prepare/commit for. (That's
1403 * broken code anyway: it's wrong for msync()).
1405 * It's a rare case: affects the final partial page, for journalled data
1406 * where the file is subject to bith write() and writepage() in the same
1407 * transction. To fix it we'll need a custom block_write_full_page().
1408 * We'll probably need that anyway for journalling writepage() output.
1410 * We don't honour synchronous mounts for writepage(). That would be
1411 * disastrous. Any write() or metadata operation will sync the fs for
1414 * AKPM2: if all the page's buffers are mapped to disk and !data=journal,
1415 * we don't need to open a transaction here.
1417 static int ext3_ordered_writepage(struct page
*page
,
1418 struct writeback_control
*wbc
)
1420 struct inode
*inode
= page
->mapping
->host
;
1421 struct buffer_head
*page_bufs
;
1422 handle_t
*handle
= NULL
;
1426 J_ASSERT(PageLocked(page
));
1429 * We give up here if we're reentered, because it might be for a
1430 * different filesystem.
1432 if (ext3_journal_current_handle())
1435 handle
= ext3_journal_start(inode
, ext3_writepage_trans_blocks(inode
));
1437 if (IS_ERR(handle
)) {
1438 ret
= PTR_ERR(handle
);
1442 if (!page_has_buffers(page
)) {
1443 create_empty_buffers(page
, inode
->i_sb
->s_blocksize
,
1444 (1 << BH_Dirty
)|(1 << BH_Uptodate
));
1446 page_bufs
= page_buffers(page
);
1447 walk_page_buffers(handle
, page_bufs
, 0,
1448 PAGE_CACHE_SIZE
, NULL
, bget_one
);
1450 ret
= block_write_full_page(page
, ext3_get_block
, wbc
);
1453 * The page can become unlocked at any point now, and
1454 * truncate can then come in and change things. So we
1455 * can't touch *page from now on. But *page_bufs is
1456 * safe due to elevated refcount.
1460 * And attach them to the current transaction. But only if
1461 * block_write_full_page() succeeded. Otherwise they are unmapped,
1462 * and generally junk.
1465 err
= walk_page_buffers(handle
, page_bufs
, 0, PAGE_CACHE_SIZE
,
1466 NULL
, journal_dirty_data_fn
);
1470 walk_page_buffers(handle
, page_bufs
, 0,
1471 PAGE_CACHE_SIZE
, NULL
, bput_one
);
1472 err
= ext3_journal_stop(handle
);
1478 redirty_page_for_writepage(wbc
, page
);
1483 static int ext3_writeback_writepage(struct page
*page
,
1484 struct writeback_control
*wbc
)
1486 struct inode
*inode
= page
->mapping
->host
;
1487 handle_t
*handle
= NULL
;
1491 if (ext3_journal_current_handle())
1494 handle
= ext3_journal_start(inode
, ext3_writepage_trans_blocks(inode
));
1495 if (IS_ERR(handle
)) {
1496 ret
= PTR_ERR(handle
);
1500 if (test_opt(inode
->i_sb
, NOBH
) && ext3_should_writeback_data(inode
))
1501 ret
= nobh_writepage(page
, ext3_get_block
, wbc
);
1503 ret
= block_write_full_page(page
, ext3_get_block
, wbc
);
1505 err
= ext3_journal_stop(handle
);
1511 redirty_page_for_writepage(wbc
, page
);
1516 static int ext3_journalled_writepage(struct page
*page
,
1517 struct writeback_control
*wbc
)
1519 struct inode
*inode
= page
->mapping
->host
;
1520 handle_t
*handle
= NULL
;
1524 if (ext3_journal_current_handle())
1527 handle
= ext3_journal_start(inode
, ext3_writepage_trans_blocks(inode
));
1528 if (IS_ERR(handle
)) {
1529 ret
= PTR_ERR(handle
);
1533 if (!page_has_buffers(page
) || PageChecked(page
)) {
1535 * It's mmapped pagecache. Add buffers and journal it. There
1536 * doesn't seem much point in redirtying the page here.
1538 ClearPageChecked(page
);
1539 ret
= block_prepare_write(page
, 0, PAGE_CACHE_SIZE
,
1542 ext3_journal_stop(handle
);
1545 ret
= walk_page_buffers(handle
, page_buffers(page
), 0,
1546 PAGE_CACHE_SIZE
, NULL
, do_journal_get_write_access
);
1548 err
= walk_page_buffers(handle
, page_buffers(page
), 0,
1549 PAGE_CACHE_SIZE
, NULL
, commit_write_fn
);
1552 EXT3_I(inode
)->i_state
|= EXT3_STATE_JDATA
;
1556 * It may be a page full of checkpoint-mode buffers. We don't
1557 * really know unless we go poke around in the buffer_heads.
1558 * But block_write_full_page will do the right thing.
1560 ret
= block_write_full_page(page
, ext3_get_block
, wbc
);
1562 err
= ext3_journal_stop(handle
);
1569 redirty_page_for_writepage(wbc
, page
);
1575 static int ext3_readpage(struct file
*file
, struct page
*page
)
1577 return mpage_readpage(page
, ext3_get_block
);
1581 ext3_readpages(struct file
*file
, struct address_space
*mapping
,
1582 struct list_head
*pages
, unsigned nr_pages
)
1584 return mpage_readpages(mapping
, pages
, nr_pages
, ext3_get_block
);
1587 static void ext3_invalidatepage(struct page
*page
, unsigned long offset
)
1589 journal_t
*journal
= EXT3_JOURNAL(page
->mapping
->host
);
1592 * If it's a full truncate we just forget about the pending dirtying
1595 ClearPageChecked(page
);
1597 journal_invalidatepage(journal
, page
, offset
);
1600 static int ext3_releasepage(struct page
*page
, gfp_t wait
)
1602 journal_t
*journal
= EXT3_JOURNAL(page
->mapping
->host
);
1604 WARN_ON(PageChecked(page
));
1605 if (!page_has_buffers(page
))
1607 return journal_try_to_free_buffers(journal
, page
, wait
);
1611 * If the O_DIRECT write will extend the file then add this inode to the
1612 * orphan list. So recovery will truncate it back to the original size
1613 * if the machine crashes during the write.
1615 * If the O_DIRECT write is intantiating holes inside i_size and the machine
1616 * crashes then stale disk data _may_ be exposed inside the file.
1618 static ssize_t
ext3_direct_IO(int rw
, struct kiocb
*iocb
,
1619 const struct iovec
*iov
, loff_t offset
,
1620 unsigned long nr_segs
)
1622 struct file
*file
= iocb
->ki_filp
;
1623 struct inode
*inode
= file
->f_mapping
->host
;
1624 struct ext3_inode_info
*ei
= EXT3_I(inode
);
1625 handle_t
*handle
= NULL
;
1628 size_t count
= iov_length(iov
, nr_segs
);
1631 loff_t final_size
= offset
+ count
;
1633 handle
= ext3_journal_start(inode
, DIO_CREDITS
);
1634 if (IS_ERR(handle
)) {
1635 ret
= PTR_ERR(handle
);
1638 if (final_size
> inode
->i_size
) {
1639 ret
= ext3_orphan_add(handle
, inode
);
1643 ei
->i_disksize
= inode
->i_size
;
1647 ret
= blockdev_direct_IO(rw
, iocb
, inode
, inode
->i_sb
->s_bdev
, iov
,
1649 ext3_get_block
, NULL
);
1652 * Reacquire the handle: ext3_get_block() can restart the transaction
1654 handle
= journal_current_handle();
1660 if (orphan
&& inode
->i_nlink
)
1661 ext3_orphan_del(handle
, inode
);
1662 if (orphan
&& ret
> 0) {
1663 loff_t end
= offset
+ ret
;
1664 if (end
> inode
->i_size
) {
1665 ei
->i_disksize
= end
;
1666 i_size_write(inode
, end
);
1668 * We're going to return a positive `ret'
1669 * here due to non-zero-length I/O, so there's
1670 * no way of reporting error returns from
1671 * ext3_mark_inode_dirty() to userspace. So
1674 ext3_mark_inode_dirty(handle
, inode
);
1677 err
= ext3_journal_stop(handle
);
1686 * Pages can be marked dirty completely asynchronously from ext3's journalling
1687 * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do
1688 * much here because ->set_page_dirty is called under VFS locks. The page is
1689 * not necessarily locked.
1691 * We cannot just dirty the page and leave attached buffers clean, because the
1692 * buffers' dirty state is "definitive". We cannot just set the buffers dirty
1693 * or jbddirty because all the journalling code will explode.
1695 * So what we do is to mark the page "pending dirty" and next time writepage
1696 * is called, propagate that into the buffers appropriately.
1698 static int ext3_journalled_set_page_dirty(struct page
*page
)
1700 SetPageChecked(page
);
1701 return __set_page_dirty_nobuffers(page
);
1704 static const struct address_space_operations ext3_ordered_aops
= {
1705 .readpage
= ext3_readpage
,
1706 .readpages
= ext3_readpages
,
1707 .writepage
= ext3_ordered_writepage
,
1708 .sync_page
= block_sync_page
,
1709 .prepare_write
= ext3_prepare_write
,
1710 .commit_write
= ext3_ordered_commit_write
,
1712 .invalidatepage
= ext3_invalidatepage
,
1713 .releasepage
= ext3_releasepage
,
1714 .direct_IO
= ext3_direct_IO
,
1715 .migratepage
= buffer_migrate_page
,
1718 static const struct address_space_operations ext3_writeback_aops
= {
1719 .readpage
= ext3_readpage
,
1720 .readpages
= ext3_readpages
,
1721 .writepage
= ext3_writeback_writepage
,
1722 .sync_page
= block_sync_page
,
1723 .prepare_write
= ext3_prepare_write
,
1724 .commit_write
= ext3_writeback_commit_write
,
1726 .invalidatepage
= ext3_invalidatepage
,
1727 .releasepage
= ext3_releasepage
,
1728 .direct_IO
= ext3_direct_IO
,
1729 .migratepage
= buffer_migrate_page
,
1732 static const struct address_space_operations ext3_journalled_aops
= {
1733 .readpage
= ext3_readpage
,
1734 .readpages
= ext3_readpages
,
1735 .writepage
= ext3_journalled_writepage
,
1736 .sync_page
= block_sync_page
,
1737 .prepare_write
= ext3_prepare_write
,
1738 .commit_write
= ext3_journalled_commit_write
,
1739 .set_page_dirty
= ext3_journalled_set_page_dirty
,
1741 .invalidatepage
= ext3_invalidatepage
,
1742 .releasepage
= ext3_releasepage
,
1745 void ext3_set_aops(struct inode
*inode
)
1747 if (ext3_should_order_data(inode
))
1748 inode
->i_mapping
->a_ops
= &ext3_ordered_aops
;
1749 else if (ext3_should_writeback_data(inode
))
1750 inode
->i_mapping
->a_ops
= &ext3_writeback_aops
;
1752 inode
->i_mapping
->a_ops
= &ext3_journalled_aops
;
1756 * ext3_block_truncate_page() zeroes out a mapping from file offset `from'
1757 * up to the end of the block which corresponds to `from'.
1758 * This required during truncate. We need to physically zero the tail end
1759 * of that block so it doesn't yield old data if the file is later grown.
1761 static int ext3_block_truncate_page(handle_t
*handle
, struct page
*page
,
1762 struct address_space
*mapping
, loff_t from
)
1764 ext3_fsblk_t index
= from
>> PAGE_CACHE_SHIFT
;
1765 unsigned offset
= from
& (PAGE_CACHE_SIZE
-1);
1766 unsigned blocksize
, iblock
, length
, pos
;
1767 struct inode
*inode
= mapping
->host
;
1768 struct buffer_head
*bh
;
1772 blocksize
= inode
->i_sb
->s_blocksize
;
1773 length
= blocksize
- (offset
& (blocksize
- 1));
1774 iblock
= index
<< (PAGE_CACHE_SHIFT
- inode
->i_sb
->s_blocksize_bits
);
1777 * For "nobh" option, we can only work if we don't need to
1778 * read-in the page - otherwise we create buffers to do the IO.
1780 if (!page_has_buffers(page
) && test_opt(inode
->i_sb
, NOBH
) &&
1781 ext3_should_writeback_data(inode
) && PageUptodate(page
)) {
1782 kaddr
= kmap_atomic(page
, KM_USER0
);
1783 memset(kaddr
+ offset
, 0, length
);
1784 flush_dcache_page(page
);
1785 kunmap_atomic(kaddr
, KM_USER0
);
1786 set_page_dirty(page
);
1790 if (!page_has_buffers(page
))
1791 create_empty_buffers(page
, blocksize
, 0);
1793 /* Find the buffer that contains "offset" */
1794 bh
= page_buffers(page
);
1796 while (offset
>= pos
) {
1797 bh
= bh
->b_this_page
;
1803 if (buffer_freed(bh
)) {
1804 BUFFER_TRACE(bh
, "freed: skip");
1808 if (!buffer_mapped(bh
)) {
1809 BUFFER_TRACE(bh
, "unmapped");
1810 ext3_get_block(inode
, iblock
, bh
, 0);
1811 /* unmapped? It's a hole - nothing to do */
1812 if (!buffer_mapped(bh
)) {
1813 BUFFER_TRACE(bh
, "still unmapped");
1818 /* Ok, it's mapped. Make sure it's up-to-date */
1819 if (PageUptodate(page
))
1820 set_buffer_uptodate(bh
);
1822 if (!buffer_uptodate(bh
)) {
1824 ll_rw_block(READ
, 1, &bh
);
1826 /* Uhhuh. Read error. Complain and punt. */
1827 if (!buffer_uptodate(bh
))
1831 if (ext3_should_journal_data(inode
)) {
1832 BUFFER_TRACE(bh
, "get write access");
1833 err
= ext3_journal_get_write_access(handle
, bh
);
1838 kaddr
= kmap_atomic(page
, KM_USER0
);
1839 memset(kaddr
+ offset
, 0, length
);
1840 flush_dcache_page(page
);
1841 kunmap_atomic(kaddr
, KM_USER0
);
1843 BUFFER_TRACE(bh
, "zeroed end of block");
1846 if (ext3_should_journal_data(inode
)) {
1847 err
= ext3_journal_dirty_metadata(handle
, bh
);
1849 if (ext3_should_order_data(inode
))
1850 err
= ext3_journal_dirty_data(handle
, bh
);
1851 mark_buffer_dirty(bh
);
1856 page_cache_release(page
);
1861 * Probably it should be a library function... search for first non-zero word
1862 * or memcmp with zero_page, whatever is better for particular architecture.
1865 static inline int all_zeroes(__le32
*p
, __le32
*q
)
1874 * ext3_find_shared - find the indirect blocks for partial truncation.
1875 * @inode: inode in question
1876 * @depth: depth of the affected branch
1877 * @offsets: offsets of pointers in that branch (see ext3_block_to_path)
1878 * @chain: place to store the pointers to partial indirect blocks
1879 * @top: place to the (detached) top of branch
1881 * This is a helper function used by ext3_truncate().
1883 * When we do truncate() we may have to clean the ends of several
1884 * indirect blocks but leave the blocks themselves alive. Block is
1885 * partially truncated if some data below the new i_size is refered
1886 * from it (and it is on the path to the first completely truncated
1887 * data block, indeed). We have to free the top of that path along
1888 * with everything to the right of the path. Since no allocation
1889 * past the truncation point is possible until ext3_truncate()
1890 * finishes, we may safely do the latter, but top of branch may
1891 * require special attention - pageout below the truncation point
1892 * might try to populate it.
1894 * We atomically detach the top of branch from the tree, store the
1895 * block number of its root in *@top, pointers to buffer_heads of
1896 * partially truncated blocks - in @chain[].bh and pointers to
1897 * their last elements that should not be removed - in
1898 * @chain[].p. Return value is the pointer to last filled element
1901 * The work left to caller to do the actual freeing of subtrees:
1902 * a) free the subtree starting from *@top
1903 * b) free the subtrees whose roots are stored in
1904 * (@chain[i].p+1 .. end of @chain[i].bh->b_data)
1905 * c) free the subtrees growing from the inode past the @chain[0].
1906 * (no partially truncated stuff there). */
1908 static Indirect
*ext3_find_shared(struct inode
*inode
, int depth
,
1909 int offsets
[4], Indirect chain
[4], __le32
*top
)
1911 Indirect
*partial
, *p
;
1915 /* Make k index the deepest non-null offest + 1 */
1916 for (k
= depth
; k
> 1 && !offsets
[k
-1]; k
--)
1918 partial
= ext3_get_branch(inode
, k
, offsets
, chain
, &err
);
1919 /* Writer: pointers */
1921 partial
= chain
+ k
-1;
1923 * If the branch acquired continuation since we've looked at it -
1924 * fine, it should all survive and (new) top doesn't belong to us.
1926 if (!partial
->key
&& *partial
->p
)
1929 for (p
=partial
; p
>chain
&& all_zeroes((__le32
*)p
->bh
->b_data
,p
->p
); p
--)
1932 * OK, we've found the last block that must survive. The rest of our
1933 * branch should be detached before unlocking. However, if that rest
1934 * of branch is all ours and does not grow immediately from the inode
1935 * it's easier to cheat and just decrement partial->p.
1937 if (p
== chain
+ k
- 1 && p
> chain
) {
1941 /* Nope, don't do this in ext3. Must leave the tree intact */
1948 while(partial
> p
) {
1949 brelse(partial
->bh
);
1957 * Zero a number of block pointers in either an inode or an indirect block.
1958 * If we restart the transaction we must again get write access to the
1959 * indirect block for further modification.
1961 * We release `count' blocks on disk, but (last - first) may be greater
1962 * than `count' because there can be holes in there.
1964 static void ext3_clear_blocks(handle_t
*handle
, struct inode
*inode
,
1965 struct buffer_head
*bh
, ext3_fsblk_t block_to_free
,
1966 unsigned long count
, __le32
*first
, __le32
*last
)
1969 if (try_to_extend_transaction(handle
, inode
)) {
1971 BUFFER_TRACE(bh
, "call ext3_journal_dirty_metadata");
1972 ext3_journal_dirty_metadata(handle
, bh
);
1974 ext3_mark_inode_dirty(handle
, inode
);
1975 ext3_journal_test_restart(handle
, inode
);
1977 BUFFER_TRACE(bh
, "retaking write access");
1978 ext3_journal_get_write_access(handle
, bh
);
1983 * Any buffers which are on the journal will be in memory. We find
1984 * them on the hash table so journal_revoke() will run journal_forget()
1985 * on them. We've already detached each block from the file, so
1986 * bforget() in journal_forget() should be safe.
1988 * AKPM: turn on bforget in journal_forget()!!!
1990 for (p
= first
; p
< last
; p
++) {
1991 u32 nr
= le32_to_cpu(*p
);
1993 struct buffer_head
*bh
;
1996 bh
= sb_find_get_block(inode
->i_sb
, nr
);
1997 ext3_forget(handle
, 0, inode
, bh
, nr
);
2001 ext3_free_blocks(handle
, inode
, block_to_free
, count
);
2005 * ext3_free_data - free a list of data blocks
2006 * @handle: handle for this transaction
2007 * @inode: inode we are dealing with
2008 * @this_bh: indirect buffer_head which contains *@first and *@last
2009 * @first: array of block numbers
2010 * @last: points immediately past the end of array
2012 * We are freeing all blocks refered from that array (numbers are stored as
2013 * little-endian 32-bit) and updating @inode->i_blocks appropriately.
2015 * We accumulate contiguous runs of blocks to free. Conveniently, if these
2016 * blocks are contiguous then releasing them at one time will only affect one
2017 * or two bitmap blocks (+ group descriptor(s) and superblock) and we won't
2018 * actually use a lot of journal space.
2020 * @this_bh will be %NULL if @first and @last point into the inode's direct
2023 static void ext3_free_data(handle_t
*handle
, struct inode
*inode
,
2024 struct buffer_head
*this_bh
,
2025 __le32
*first
, __le32
*last
)
2027 ext3_fsblk_t block_to_free
= 0; /* Starting block # of a run */
2028 unsigned long count
= 0; /* Number of blocks in the run */
2029 __le32
*block_to_free_p
= NULL
; /* Pointer into inode/ind
2032 ext3_fsblk_t nr
; /* Current block # */
2033 __le32
*p
; /* Pointer into inode/ind
2034 for current block */
2037 if (this_bh
) { /* For indirect block */
2038 BUFFER_TRACE(this_bh
, "get_write_access");
2039 err
= ext3_journal_get_write_access(handle
, this_bh
);
2040 /* Important: if we can't update the indirect pointers
2041 * to the blocks, we can't free them. */
2046 for (p
= first
; p
< last
; p
++) {
2047 nr
= le32_to_cpu(*p
);
2049 /* accumulate blocks to free if they're contiguous */
2052 block_to_free_p
= p
;
2054 } else if (nr
== block_to_free
+ count
) {
2057 ext3_clear_blocks(handle
, inode
, this_bh
,
2059 count
, block_to_free_p
, p
);
2061 block_to_free_p
= p
;
2068 ext3_clear_blocks(handle
, inode
, this_bh
, block_to_free
,
2069 count
, block_to_free_p
, p
);
2072 BUFFER_TRACE(this_bh
, "call ext3_journal_dirty_metadata");
2073 ext3_journal_dirty_metadata(handle
, this_bh
);
2078 * ext3_free_branches - free an array of branches
2079 * @handle: JBD handle for this transaction
2080 * @inode: inode we are dealing with
2081 * @parent_bh: the buffer_head which contains *@first and *@last
2082 * @first: array of block numbers
2083 * @last: pointer immediately past the end of array
2084 * @depth: depth of the branches to free
2086 * We are freeing all blocks refered from these branches (numbers are
2087 * stored as little-endian 32-bit) and updating @inode->i_blocks
2090 static void ext3_free_branches(handle_t
*handle
, struct inode
*inode
,
2091 struct buffer_head
*parent_bh
,
2092 __le32
*first
, __le32
*last
, int depth
)
2097 if (is_handle_aborted(handle
))
2101 struct buffer_head
*bh
;
2102 int addr_per_block
= EXT3_ADDR_PER_BLOCK(inode
->i_sb
);
2104 while (--p
>= first
) {
2105 nr
= le32_to_cpu(*p
);
2107 continue; /* A hole */
2109 /* Go read the buffer for the next level down */
2110 bh
= sb_bread(inode
->i_sb
, nr
);
2113 * A read failure? Report error and clear slot
2117 ext3_error(inode
->i_sb
, "ext3_free_branches",
2118 "Read failure, inode=%lu, block="E3FSBLK
,
2123 /* This zaps the entire block. Bottom up. */
2124 BUFFER_TRACE(bh
, "free child branches");
2125 ext3_free_branches(handle
, inode
, bh
,
2126 (__le32
*)bh
->b_data
,
2127 (__le32
*)bh
->b_data
+ addr_per_block
,
2131 * We've probably journalled the indirect block several
2132 * times during the truncate. But it's no longer
2133 * needed and we now drop it from the transaction via
2136 * That's easy if it's exclusively part of this
2137 * transaction. But if it's part of the committing
2138 * transaction then journal_forget() will simply
2139 * brelse() it. That means that if the underlying
2140 * block is reallocated in ext3_get_block(),
2141 * unmap_underlying_metadata() will find this block
2142 * and will try to get rid of it. damn, damn.
2144 * If this block has already been committed to the
2145 * journal, a revoke record will be written. And
2146 * revoke records must be emitted *before* clearing
2147 * this block's bit in the bitmaps.
2149 ext3_forget(handle
, 1, inode
, bh
, bh
->b_blocknr
);
2152 * Everything below this this pointer has been
2153 * released. Now let this top-of-subtree go.
2155 * We want the freeing of this indirect block to be
2156 * atomic in the journal with the updating of the
2157 * bitmap block which owns it. So make some room in
2160 * We zero the parent pointer *after* freeing its
2161 * pointee in the bitmaps, so if extend_transaction()
2162 * for some reason fails to put the bitmap changes and
2163 * the release into the same transaction, recovery
2164 * will merely complain about releasing a free block,
2165 * rather than leaking blocks.
2167 if (is_handle_aborted(handle
))
2169 if (try_to_extend_transaction(handle
, inode
)) {
2170 ext3_mark_inode_dirty(handle
, inode
);
2171 ext3_journal_test_restart(handle
, inode
);
2174 ext3_free_blocks(handle
, inode
, nr
, 1);
2178 * The block which we have just freed is
2179 * pointed to by an indirect block: journal it
2181 BUFFER_TRACE(parent_bh
, "get_write_access");
2182 if (!ext3_journal_get_write_access(handle
,
2185 BUFFER_TRACE(parent_bh
,
2186 "call ext3_journal_dirty_metadata");
2187 ext3_journal_dirty_metadata(handle
,
2193 /* We have reached the bottom of the tree. */
2194 BUFFER_TRACE(parent_bh
, "free data blocks");
2195 ext3_free_data(handle
, inode
, parent_bh
, first
, last
);
2202 * We block out ext3_get_block() block instantiations across the entire
2203 * transaction, and VFS/VM ensures that ext3_truncate() cannot run
2204 * simultaneously on behalf of the same inode.
2206 * As we work through the truncate and commmit bits of it to the journal there
2207 * is one core, guiding principle: the file's tree must always be consistent on
2208 * disk. We must be able to restart the truncate after a crash.
2210 * The file's tree may be transiently inconsistent in memory (although it
2211 * probably isn't), but whenever we close off and commit a journal transaction,
2212 * the contents of (the filesystem + the journal) must be consistent and
2213 * restartable. It's pretty simple, really: bottom up, right to left (although
2214 * left-to-right works OK too).
2216 * Note that at recovery time, journal replay occurs *before* the restart of
2217 * truncate against the orphan inode list.
2219 * The committed inode has the new, desired i_size (which is the same as
2220 * i_disksize in this case). After a crash, ext3_orphan_cleanup() will see
2221 * that this inode's truncate did not complete and it will again call
2222 * ext3_truncate() to have another go. So there will be instantiated blocks
2223 * to the right of the truncation point in a crashed ext3 filesystem. But
2224 * that's fine - as long as they are linked from the inode, the post-crash
2225 * ext3_truncate() run will find them and release them.
2227 void ext3_truncate(struct inode
*inode
)
2230 struct ext3_inode_info
*ei
= EXT3_I(inode
);
2231 __le32
*i_data
= ei
->i_data
;
2232 int addr_per_block
= EXT3_ADDR_PER_BLOCK(inode
->i_sb
);
2233 struct address_space
*mapping
= inode
->i_mapping
;
2240 unsigned blocksize
= inode
->i_sb
->s_blocksize
;
2243 if (!(S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
) ||
2244 S_ISLNK(inode
->i_mode
)))
2246 if (ext3_inode_is_fast_symlink(inode
))
2248 if (IS_APPEND(inode
) || IS_IMMUTABLE(inode
))
2252 * We have to lock the EOF page here, because lock_page() nests
2253 * outside journal_start().
2255 if ((inode
->i_size
& (blocksize
- 1)) == 0) {
2256 /* Block boundary? Nothing to do */
2259 page
= grab_cache_page(mapping
,
2260 inode
->i_size
>> PAGE_CACHE_SHIFT
);
2265 handle
= start_transaction(inode
);
2266 if (IS_ERR(handle
)) {
2268 clear_highpage(page
);
2269 flush_dcache_page(page
);
2271 page_cache_release(page
);
2273 return; /* AKPM: return what? */
2276 last_block
= (inode
->i_size
+ blocksize
-1)
2277 >> EXT3_BLOCK_SIZE_BITS(inode
->i_sb
);
2280 ext3_block_truncate_page(handle
, page
, mapping
, inode
->i_size
);
2282 n
= ext3_block_to_path(inode
, last_block
, offsets
, NULL
);
2284 goto out_stop
; /* error */
2287 * OK. This truncate is going to happen. We add the inode to the
2288 * orphan list, so that if this truncate spans multiple transactions,
2289 * and we crash, we will resume the truncate when the filesystem
2290 * recovers. It also marks the inode dirty, to catch the new size.
2292 * Implication: the file must always be in a sane, consistent
2293 * truncatable state while each transaction commits.
2295 if (ext3_orphan_add(handle
, inode
))
2299 * The orphan list entry will now protect us from any crash which
2300 * occurs before the truncate completes, so it is now safe to propagate
2301 * the new, shorter inode size (held for now in i_size) into the
2302 * on-disk inode. We do this via i_disksize, which is the value which
2303 * ext3 *really* writes onto the disk inode.
2305 ei
->i_disksize
= inode
->i_size
;
2308 * From here we block out all ext3_get_block() callers who want to
2309 * modify the block allocation tree.
2311 mutex_lock(&ei
->truncate_mutex
);
2313 if (n
== 1) { /* direct blocks */
2314 ext3_free_data(handle
, inode
, NULL
, i_data
+offsets
[0],
2315 i_data
+ EXT3_NDIR_BLOCKS
);
2319 partial
= ext3_find_shared(inode
, n
, offsets
, chain
, &nr
);
2320 /* Kill the top of shared branch (not detached) */
2322 if (partial
== chain
) {
2323 /* Shared branch grows from the inode */
2324 ext3_free_branches(handle
, inode
, NULL
,
2325 &nr
, &nr
+1, (chain
+n
-1) - partial
);
2328 * We mark the inode dirty prior to restart,
2329 * and prior to stop. No need for it here.
2332 /* Shared branch grows from an indirect block */
2333 BUFFER_TRACE(partial
->bh
, "get_write_access");
2334 ext3_free_branches(handle
, inode
, partial
->bh
,
2336 partial
->p
+1, (chain
+n
-1) - partial
);
2339 /* Clear the ends of indirect blocks on the shared branch */
2340 while (partial
> chain
) {
2341 ext3_free_branches(handle
, inode
, partial
->bh
, partial
->p
+ 1,
2342 (__le32
*)partial
->bh
->b_data
+addr_per_block
,
2343 (chain
+n
-1) - partial
);
2344 BUFFER_TRACE(partial
->bh
, "call brelse");
2345 brelse (partial
->bh
);
2349 /* Kill the remaining (whole) subtrees */
2350 switch (offsets
[0]) {
2352 nr
= i_data
[EXT3_IND_BLOCK
];
2354 ext3_free_branches(handle
, inode
, NULL
, &nr
, &nr
+1, 1);
2355 i_data
[EXT3_IND_BLOCK
] = 0;
2357 case EXT3_IND_BLOCK
:
2358 nr
= i_data
[EXT3_DIND_BLOCK
];
2360 ext3_free_branches(handle
, inode
, NULL
, &nr
, &nr
+1, 2);
2361 i_data
[EXT3_DIND_BLOCK
] = 0;
2363 case EXT3_DIND_BLOCK
:
2364 nr
= i_data
[EXT3_TIND_BLOCK
];
2366 ext3_free_branches(handle
, inode
, NULL
, &nr
, &nr
+1, 3);
2367 i_data
[EXT3_TIND_BLOCK
] = 0;
2369 case EXT3_TIND_BLOCK
:
2373 ext3_discard_reservation(inode
);
2375 mutex_unlock(&ei
->truncate_mutex
);
2376 inode
->i_mtime
= inode
->i_ctime
= CURRENT_TIME_SEC
;
2377 ext3_mark_inode_dirty(handle
, inode
);
2380 * In a multi-transaction truncate, we only make the final transaction
2387 * If this was a simple ftruncate(), and the file will remain alive
2388 * then we need to clear up the orphan record which we created above.
2389 * However, if this was a real unlink then we were called by
2390 * ext3_delete_inode(), and we allow that function to clean up the
2391 * orphan info for us.
2394 ext3_orphan_del(handle
, inode
);
2396 ext3_journal_stop(handle
);
2399 static ext3_fsblk_t
ext3_get_inode_block(struct super_block
*sb
,
2400 unsigned long ino
, struct ext3_iloc
*iloc
)
2402 unsigned long desc
, group_desc
, block_group
;
2403 unsigned long offset
;
2405 struct buffer_head
*bh
;
2406 struct ext3_group_desc
* gdp
;
2408 if (!ext3_valid_inum(sb
, ino
)) {
2410 * This error is already checked for in namei.c unless we are
2411 * looking at an NFS filehandle, in which case no error
2417 block_group
= (ino
- 1) / EXT3_INODES_PER_GROUP(sb
);
2418 if (block_group
>= EXT3_SB(sb
)->s_groups_count
) {
2419 ext3_error(sb
,"ext3_get_inode_block","group >= groups count");
2423 group_desc
= block_group
>> EXT3_DESC_PER_BLOCK_BITS(sb
);
2424 desc
= block_group
& (EXT3_DESC_PER_BLOCK(sb
) - 1);
2425 bh
= EXT3_SB(sb
)->s_group_desc
[group_desc
];
2427 ext3_error (sb
, "ext3_get_inode_block",
2428 "Descriptor not loaded");
2432 gdp
= (struct ext3_group_desc
*)bh
->b_data
;
2434 * Figure out the offset within the block group inode table
2436 offset
= ((ino
- 1) % EXT3_INODES_PER_GROUP(sb
)) *
2437 EXT3_INODE_SIZE(sb
);
2438 block
= le32_to_cpu(gdp
[desc
].bg_inode_table
) +
2439 (offset
>> EXT3_BLOCK_SIZE_BITS(sb
));
2441 iloc
->block_group
= block_group
;
2442 iloc
->offset
= offset
& (EXT3_BLOCK_SIZE(sb
) - 1);
2447 * ext3_get_inode_loc returns with an extra refcount against the inode's
2448 * underlying buffer_head on success. If 'in_mem' is true, we have all
2449 * data in memory that is needed to recreate the on-disk version of this
2452 static int __ext3_get_inode_loc(struct inode
*inode
,
2453 struct ext3_iloc
*iloc
, int in_mem
)
2456 struct buffer_head
*bh
;
2458 block
= ext3_get_inode_block(inode
->i_sb
, inode
->i_ino
, iloc
);
2462 bh
= sb_getblk(inode
->i_sb
, block
);
2464 ext3_error (inode
->i_sb
, "ext3_get_inode_loc",
2465 "unable to read inode block - "
2466 "inode=%lu, block="E3FSBLK
,
2467 inode
->i_ino
, block
);
2470 if (!buffer_uptodate(bh
)) {
2472 if (buffer_uptodate(bh
)) {
2473 /* someone brought it uptodate while we waited */
2479 * If we have all information of the inode in memory and this
2480 * is the only valid inode in the block, we need not read the
2484 struct buffer_head
*bitmap_bh
;
2485 struct ext3_group_desc
*desc
;
2486 int inodes_per_buffer
;
2487 int inode_offset
, i
;
2491 block_group
= (inode
->i_ino
- 1) /
2492 EXT3_INODES_PER_GROUP(inode
->i_sb
);
2493 inodes_per_buffer
= bh
->b_size
/
2494 EXT3_INODE_SIZE(inode
->i_sb
);
2495 inode_offset
= ((inode
->i_ino
- 1) %
2496 EXT3_INODES_PER_GROUP(inode
->i_sb
));
2497 start
= inode_offset
& ~(inodes_per_buffer
- 1);
2499 /* Is the inode bitmap in cache? */
2500 desc
= ext3_get_group_desc(inode
->i_sb
,
2505 bitmap_bh
= sb_getblk(inode
->i_sb
,
2506 le32_to_cpu(desc
->bg_inode_bitmap
));
2511 * If the inode bitmap isn't in cache then the
2512 * optimisation may end up performing two reads instead
2513 * of one, so skip it.
2515 if (!buffer_uptodate(bitmap_bh
)) {
2519 for (i
= start
; i
< start
+ inodes_per_buffer
; i
++) {
2520 if (i
== inode_offset
)
2522 if (ext3_test_bit(i
, bitmap_bh
->b_data
))
2526 if (i
== start
+ inodes_per_buffer
) {
2527 /* all other inodes are free, so skip I/O */
2528 memset(bh
->b_data
, 0, bh
->b_size
);
2529 set_buffer_uptodate(bh
);
2537 * There are other valid inodes in the buffer, this inode
2538 * has in-inode xattrs, or we don't have this inode in memory.
2539 * Read the block from disk.
2542 bh
->b_end_io
= end_buffer_read_sync
;
2543 submit_bh(READ
, bh
);
2545 if (!buffer_uptodate(bh
)) {
2546 ext3_error(inode
->i_sb
, "ext3_get_inode_loc",
2547 "unable to read inode block - "
2548 "inode=%lu, block="E3FSBLK
,
2549 inode
->i_ino
, block
);
2559 int ext3_get_inode_loc(struct inode
*inode
, struct ext3_iloc
*iloc
)
2561 /* We have all inode data except xattrs in memory here. */
2562 return __ext3_get_inode_loc(inode
, iloc
,
2563 !(EXT3_I(inode
)->i_state
& EXT3_STATE_XATTR
));
2566 void ext3_set_inode_flags(struct inode
*inode
)
2568 unsigned int flags
= EXT3_I(inode
)->i_flags
;
2570 inode
->i_flags
&= ~(S_SYNC
|S_APPEND
|S_IMMUTABLE
|S_NOATIME
|S_DIRSYNC
);
2571 if (flags
& EXT3_SYNC_FL
)
2572 inode
->i_flags
|= S_SYNC
;
2573 if (flags
& EXT3_APPEND_FL
)
2574 inode
->i_flags
|= S_APPEND
;
2575 if (flags
& EXT3_IMMUTABLE_FL
)
2576 inode
->i_flags
|= S_IMMUTABLE
;
2577 if (flags
& EXT3_NOATIME_FL
)
2578 inode
->i_flags
|= S_NOATIME
;
2579 if (flags
& EXT3_DIRSYNC_FL
)
2580 inode
->i_flags
|= S_DIRSYNC
;
2583 void ext3_read_inode(struct inode
* inode
)
2585 struct ext3_iloc iloc
;
2586 struct ext3_inode
*raw_inode
;
2587 struct ext3_inode_info
*ei
= EXT3_I(inode
);
2588 struct buffer_head
*bh
;
2591 #ifdef CONFIG_EXT3_FS_POSIX_ACL
2592 ei
->i_acl
= EXT3_ACL_NOT_CACHED
;
2593 ei
->i_default_acl
= EXT3_ACL_NOT_CACHED
;
2595 ei
->i_block_alloc_info
= NULL
;
2597 if (__ext3_get_inode_loc(inode
, &iloc
, 0))
2600 raw_inode
= ext3_raw_inode(&iloc
);
2601 inode
->i_mode
= le16_to_cpu(raw_inode
->i_mode
);
2602 inode
->i_uid
= (uid_t
)le16_to_cpu(raw_inode
->i_uid_low
);
2603 inode
->i_gid
= (gid_t
)le16_to_cpu(raw_inode
->i_gid_low
);
2604 if(!(test_opt (inode
->i_sb
, NO_UID32
))) {
2605 inode
->i_uid
|= le16_to_cpu(raw_inode
->i_uid_high
) << 16;
2606 inode
->i_gid
|= le16_to_cpu(raw_inode
->i_gid_high
) << 16;
2608 inode
->i_nlink
= le16_to_cpu(raw_inode
->i_links_count
);
2609 inode
->i_size
= le32_to_cpu(raw_inode
->i_size
);
2610 inode
->i_atime
.tv_sec
= le32_to_cpu(raw_inode
->i_atime
);
2611 inode
->i_ctime
.tv_sec
= le32_to_cpu(raw_inode
->i_ctime
);
2612 inode
->i_mtime
.tv_sec
= le32_to_cpu(raw_inode
->i_mtime
);
2613 inode
->i_atime
.tv_nsec
= inode
->i_ctime
.tv_nsec
= inode
->i_mtime
.tv_nsec
= 0;
2616 ei
->i_dir_start_lookup
= 0;
2617 ei
->i_dtime
= le32_to_cpu(raw_inode
->i_dtime
);
2618 /* We now have enough fields to check if the inode was active or not.
2619 * This is needed because nfsd might try to access dead inodes
2620 * the test is that same one that e2fsck uses
2621 * NeilBrown 1999oct15
2623 if (inode
->i_nlink
== 0) {
2624 if (inode
->i_mode
== 0 ||
2625 !(EXT3_SB(inode
->i_sb
)->s_mount_state
& EXT3_ORPHAN_FS
)) {
2626 /* this inode is deleted */
2630 /* The only unlinked inodes we let through here have
2631 * valid i_mode and are being read by the orphan
2632 * recovery code: that's fine, we're about to complete
2633 * the process of deleting those. */
2635 inode
->i_blksize
= PAGE_SIZE
; /* This is the optimal IO size
2636 * (for stat), not the fs block
2638 inode
->i_blocks
= le32_to_cpu(raw_inode
->i_blocks
);
2639 ei
->i_flags
= le32_to_cpu(raw_inode
->i_flags
);
2640 #ifdef EXT3_FRAGMENTS
2641 ei
->i_faddr
= le32_to_cpu(raw_inode
->i_faddr
);
2642 ei
->i_frag_no
= raw_inode
->i_frag
;
2643 ei
->i_frag_size
= raw_inode
->i_fsize
;
2645 ei
->i_file_acl
= le32_to_cpu(raw_inode
->i_file_acl
);
2646 if (!S_ISREG(inode
->i_mode
)) {
2647 ei
->i_dir_acl
= le32_to_cpu(raw_inode
->i_dir_acl
);
2650 ((__u64
)le32_to_cpu(raw_inode
->i_size_high
)) << 32;
2652 ei
->i_disksize
= inode
->i_size
;
2653 inode
->i_generation
= le32_to_cpu(raw_inode
->i_generation
);
2654 ei
->i_block_group
= iloc
.block_group
;
2656 * NOTE! The in-memory inode i_data array is in little-endian order
2657 * even on big-endian machines: we do NOT byteswap the block numbers!
2659 for (block
= 0; block
< EXT3_N_BLOCKS
; block
++)
2660 ei
->i_data
[block
] = raw_inode
->i_block
[block
];
2661 INIT_LIST_HEAD(&ei
->i_orphan
);
2663 if (inode
->i_ino
>= EXT3_FIRST_INO(inode
->i_sb
) + 1 &&
2664 EXT3_INODE_SIZE(inode
->i_sb
) > EXT3_GOOD_OLD_INODE_SIZE
) {
2666 * When mke2fs creates big inodes it does not zero out
2667 * the unused bytes above EXT3_GOOD_OLD_INODE_SIZE,
2668 * so ignore those first few inodes.
2670 ei
->i_extra_isize
= le16_to_cpu(raw_inode
->i_extra_isize
);
2671 if (EXT3_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
>
2672 EXT3_INODE_SIZE(inode
->i_sb
))
2674 if (ei
->i_extra_isize
== 0) {
2675 /* The extra space is currently unused. Use it. */
2676 ei
->i_extra_isize
= sizeof(struct ext3_inode
) -
2677 EXT3_GOOD_OLD_INODE_SIZE
;
2679 __le32
*magic
= (void *)raw_inode
+
2680 EXT3_GOOD_OLD_INODE_SIZE
+
2682 if (*magic
== cpu_to_le32(EXT3_XATTR_MAGIC
))
2683 ei
->i_state
|= EXT3_STATE_XATTR
;
2686 ei
->i_extra_isize
= 0;
2688 if (S_ISREG(inode
->i_mode
)) {
2689 inode
->i_op
= &ext3_file_inode_operations
;
2690 inode
->i_fop
= &ext3_file_operations
;
2691 ext3_set_aops(inode
);
2692 } else if (S_ISDIR(inode
->i_mode
)) {
2693 inode
->i_op
= &ext3_dir_inode_operations
;
2694 inode
->i_fop
= &ext3_dir_operations
;
2695 } else if (S_ISLNK(inode
->i_mode
)) {
2696 if (ext3_inode_is_fast_symlink(inode
))
2697 inode
->i_op
= &ext3_fast_symlink_inode_operations
;
2699 inode
->i_op
= &ext3_symlink_inode_operations
;
2700 ext3_set_aops(inode
);
2703 inode
->i_op
= &ext3_special_inode_operations
;
2704 if (raw_inode
->i_block
[0])
2705 init_special_inode(inode
, inode
->i_mode
,
2706 old_decode_dev(le32_to_cpu(raw_inode
->i_block
[0])));
2708 init_special_inode(inode
, inode
->i_mode
,
2709 new_decode_dev(le32_to_cpu(raw_inode
->i_block
[1])));
2712 ext3_set_inode_flags(inode
);
2716 make_bad_inode(inode
);
2721 * Post the struct inode info into an on-disk inode location in the
2722 * buffer-cache. This gobbles the caller's reference to the
2723 * buffer_head in the inode location struct.
2725 * The caller must have write access to iloc->bh.
2727 static int ext3_do_update_inode(handle_t
*handle
,
2728 struct inode
*inode
,
2729 struct ext3_iloc
*iloc
)
2731 struct ext3_inode
*raw_inode
= ext3_raw_inode(iloc
);
2732 struct ext3_inode_info
*ei
= EXT3_I(inode
);
2733 struct buffer_head
*bh
= iloc
->bh
;
2734 int err
= 0, rc
, block
;
2736 /* For fields not not tracking in the in-memory inode,
2737 * initialise them to zero for new inodes. */
2738 if (ei
->i_state
& EXT3_STATE_NEW
)
2739 memset(raw_inode
, 0, EXT3_SB(inode
->i_sb
)->s_inode_size
);
2741 raw_inode
->i_mode
= cpu_to_le16(inode
->i_mode
);
2742 if(!(test_opt(inode
->i_sb
, NO_UID32
))) {
2743 raw_inode
->i_uid_low
= cpu_to_le16(low_16_bits(inode
->i_uid
));
2744 raw_inode
->i_gid_low
= cpu_to_le16(low_16_bits(inode
->i_gid
));
2746 * Fix up interoperability with old kernels. Otherwise, old inodes get
2747 * re-used with the upper 16 bits of the uid/gid intact
2750 raw_inode
->i_uid_high
=
2751 cpu_to_le16(high_16_bits(inode
->i_uid
));
2752 raw_inode
->i_gid_high
=
2753 cpu_to_le16(high_16_bits(inode
->i_gid
));
2755 raw_inode
->i_uid_high
= 0;
2756 raw_inode
->i_gid_high
= 0;
2759 raw_inode
->i_uid_low
=
2760 cpu_to_le16(fs_high2lowuid(inode
->i_uid
));
2761 raw_inode
->i_gid_low
=
2762 cpu_to_le16(fs_high2lowgid(inode
->i_gid
));
2763 raw_inode
->i_uid_high
= 0;
2764 raw_inode
->i_gid_high
= 0;
2766 raw_inode
->i_links_count
= cpu_to_le16(inode
->i_nlink
);
2767 raw_inode
->i_size
= cpu_to_le32(ei
->i_disksize
);
2768 raw_inode
->i_atime
= cpu_to_le32(inode
->i_atime
.tv_sec
);
2769 raw_inode
->i_ctime
= cpu_to_le32(inode
->i_ctime
.tv_sec
);
2770 raw_inode
->i_mtime
= cpu_to_le32(inode
->i_mtime
.tv_sec
);
2771 raw_inode
->i_blocks
= cpu_to_le32(inode
->i_blocks
);
2772 raw_inode
->i_dtime
= cpu_to_le32(ei
->i_dtime
);
2773 raw_inode
->i_flags
= cpu_to_le32(ei
->i_flags
);
2774 #ifdef EXT3_FRAGMENTS
2775 raw_inode
->i_faddr
= cpu_to_le32(ei
->i_faddr
);
2776 raw_inode
->i_frag
= ei
->i_frag_no
;
2777 raw_inode
->i_fsize
= ei
->i_frag_size
;
2779 raw_inode
->i_file_acl
= cpu_to_le32(ei
->i_file_acl
);
2780 if (!S_ISREG(inode
->i_mode
)) {
2781 raw_inode
->i_dir_acl
= cpu_to_le32(ei
->i_dir_acl
);
2783 raw_inode
->i_size_high
=
2784 cpu_to_le32(ei
->i_disksize
>> 32);
2785 if (ei
->i_disksize
> 0x7fffffffULL
) {
2786 struct super_block
*sb
= inode
->i_sb
;
2787 if (!EXT3_HAS_RO_COMPAT_FEATURE(sb
,
2788 EXT3_FEATURE_RO_COMPAT_LARGE_FILE
) ||
2789 EXT3_SB(sb
)->s_es
->s_rev_level
==
2790 cpu_to_le32(EXT3_GOOD_OLD_REV
)) {
2791 /* If this is the first large file
2792 * created, add a flag to the superblock.
2794 err
= ext3_journal_get_write_access(handle
,
2795 EXT3_SB(sb
)->s_sbh
);
2798 ext3_update_dynamic_rev(sb
);
2799 EXT3_SET_RO_COMPAT_FEATURE(sb
,
2800 EXT3_FEATURE_RO_COMPAT_LARGE_FILE
);
2803 err
= ext3_journal_dirty_metadata(handle
,
2804 EXT3_SB(sb
)->s_sbh
);
2808 raw_inode
->i_generation
= cpu_to_le32(inode
->i_generation
);
2809 if (S_ISCHR(inode
->i_mode
) || S_ISBLK(inode
->i_mode
)) {
2810 if (old_valid_dev(inode
->i_rdev
)) {
2811 raw_inode
->i_block
[0] =
2812 cpu_to_le32(old_encode_dev(inode
->i_rdev
));
2813 raw_inode
->i_block
[1] = 0;
2815 raw_inode
->i_block
[0] = 0;
2816 raw_inode
->i_block
[1] =
2817 cpu_to_le32(new_encode_dev(inode
->i_rdev
));
2818 raw_inode
->i_block
[2] = 0;
2820 } else for (block
= 0; block
< EXT3_N_BLOCKS
; block
++)
2821 raw_inode
->i_block
[block
] = ei
->i_data
[block
];
2823 if (ei
->i_extra_isize
)
2824 raw_inode
->i_extra_isize
= cpu_to_le16(ei
->i_extra_isize
);
2826 BUFFER_TRACE(bh
, "call ext3_journal_dirty_metadata");
2827 rc
= ext3_journal_dirty_metadata(handle
, bh
);
2830 ei
->i_state
&= ~EXT3_STATE_NEW
;
2834 ext3_std_error(inode
->i_sb
, err
);
2839 * ext3_write_inode()
2841 * We are called from a few places:
2843 * - Within generic_file_write() for O_SYNC files.
2844 * Here, there will be no transaction running. We wait for any running
2845 * trasnaction to commit.
2847 * - Within sys_sync(), kupdate and such.
2848 * We wait on commit, if tol to.
2850 * - Within prune_icache() (PF_MEMALLOC == true)
2851 * Here we simply return. We can't afford to block kswapd on the
2854 * In all cases it is actually safe for us to return without doing anything,
2855 * because the inode has been copied into a raw inode buffer in
2856 * ext3_mark_inode_dirty(). This is a correctness thing for O_SYNC and for
2859 * Note that we are absolutely dependent upon all inode dirtiers doing the
2860 * right thing: they *must* call mark_inode_dirty() after dirtying info in
2861 * which we are interested.
2863 * It would be a bug for them to not do this. The code:
2865 * mark_inode_dirty(inode)
2867 * inode->i_size = expr;
2869 * is in error because a kswapd-driven write_inode() could occur while
2870 * `stuff()' is running, and the new i_size will be lost. Plus the inode
2871 * will no longer be on the superblock's dirty inode list.
2873 int ext3_write_inode(struct inode
*inode
, int wait
)
2875 if (current
->flags
& PF_MEMALLOC
)
2878 if (ext3_journal_current_handle()) {
2879 jbd_debug(0, "called recursively, non-PF_MEMALLOC!\n");
2887 return ext3_force_commit(inode
->i_sb
);
2893 * Called from notify_change.
2895 * We want to trap VFS attempts to truncate the file as soon as
2896 * possible. In particular, we want to make sure that when the VFS
2897 * shrinks i_size, we put the inode on the orphan list and modify
2898 * i_disksize immediately, so that during the subsequent flushing of
2899 * dirty pages and freeing of disk blocks, we can guarantee that any
2900 * commit will leave the blocks being flushed in an unused state on
2901 * disk. (On recovery, the inode will get truncated and the blocks will
2902 * be freed, so we have a strong guarantee that no future commit will
2903 * leave these blocks visible to the user.)
2905 * Called with inode->sem down.
2907 int ext3_setattr(struct dentry
*dentry
, struct iattr
*attr
)
2909 struct inode
*inode
= dentry
->d_inode
;
2911 const unsigned int ia_valid
= attr
->ia_valid
;
2913 error
= inode_change_ok(inode
, attr
);
2917 if ((ia_valid
& ATTR_UID
&& attr
->ia_uid
!= inode
->i_uid
) ||
2918 (ia_valid
& ATTR_GID
&& attr
->ia_gid
!= inode
->i_gid
)) {
2921 /* (user+group)*(old+new) structure, inode write (sb,
2922 * inode block, ? - but truncate inode update has it) */
2923 handle
= ext3_journal_start(inode
, 2*(EXT3_QUOTA_INIT_BLOCKS(inode
->i_sb
)+
2924 EXT3_QUOTA_DEL_BLOCKS(inode
->i_sb
))+3);
2925 if (IS_ERR(handle
)) {
2926 error
= PTR_ERR(handle
);
2929 error
= DQUOT_TRANSFER(inode
, attr
) ? -EDQUOT
: 0;
2931 ext3_journal_stop(handle
);
2934 /* Update corresponding info in inode so that everything is in
2935 * one transaction */
2936 if (attr
->ia_valid
& ATTR_UID
)
2937 inode
->i_uid
= attr
->ia_uid
;
2938 if (attr
->ia_valid
& ATTR_GID
)
2939 inode
->i_gid
= attr
->ia_gid
;
2940 error
= ext3_mark_inode_dirty(handle
, inode
);
2941 ext3_journal_stop(handle
);
2944 if (S_ISREG(inode
->i_mode
) &&
2945 attr
->ia_valid
& ATTR_SIZE
&& attr
->ia_size
< inode
->i_size
) {
2948 handle
= ext3_journal_start(inode
, 3);
2949 if (IS_ERR(handle
)) {
2950 error
= PTR_ERR(handle
);
2954 error
= ext3_orphan_add(handle
, inode
);
2955 EXT3_I(inode
)->i_disksize
= attr
->ia_size
;
2956 rc
= ext3_mark_inode_dirty(handle
, inode
);
2959 ext3_journal_stop(handle
);
2962 rc
= inode_setattr(inode
, attr
);
2964 /* If inode_setattr's call to ext3_truncate failed to get a
2965 * transaction handle at all, we need to clean up the in-core
2966 * orphan list manually. */
2968 ext3_orphan_del(NULL
, inode
);
2970 if (!rc
&& (ia_valid
& ATTR_MODE
))
2971 rc
= ext3_acl_chmod(inode
);
2974 ext3_std_error(inode
->i_sb
, error
);
2982 * How many blocks doth make a writepage()?
2984 * With N blocks per page, it may be:
2989 * N+5 bitmap blocks (from the above)
2990 * N+5 group descriptor summary blocks
2993 * 2 * EXT3_SINGLEDATA_TRANS_BLOCKS for the quote files
2995 * 3 * (N + 5) + 2 + 2 * EXT3_SINGLEDATA_TRANS_BLOCKS
2997 * With ordered or writeback data it's the same, less the N data blocks.
2999 * If the inode's direct blocks can hold an integral number of pages then a
3000 * page cannot straddle two indirect blocks, and we can only touch one indirect
3001 * and dindirect block, and the "5" above becomes "3".
3003 * This still overestimates under most circumstances. If we were to pass the
3004 * start and end offsets in here as well we could do block_to_path() on each
3005 * block and work out the exact number of indirects which are touched. Pah.
3008 static int ext3_writepage_trans_blocks(struct inode
*inode
)
3010 int bpp
= ext3_journal_blocks_per_page(inode
);
3011 int indirects
= (EXT3_NDIR_BLOCKS
% bpp
) ? 5 : 3;
3014 if (ext3_should_journal_data(inode
))
3015 ret
= 3 * (bpp
+ indirects
) + 2;
3017 ret
= 2 * (bpp
+ indirects
) + 2;
3020 /* We know that structure was already allocated during DQUOT_INIT so
3021 * we will be updating only the data blocks + inodes */
3022 ret
+= 2*EXT3_QUOTA_TRANS_BLOCKS(inode
->i_sb
);
3029 * The caller must have previously called ext3_reserve_inode_write().
3030 * Give this, we know that the caller already has write access to iloc->bh.
3032 int ext3_mark_iloc_dirty(handle_t
*handle
,
3033 struct inode
*inode
, struct ext3_iloc
*iloc
)
3037 /* the do_update_inode consumes one bh->b_count */
3040 /* ext3_do_update_inode() does journal_dirty_metadata */
3041 err
= ext3_do_update_inode(handle
, inode
, iloc
);
3047 * On success, We end up with an outstanding reference count against
3048 * iloc->bh. This _must_ be cleaned up later.
3052 ext3_reserve_inode_write(handle_t
*handle
, struct inode
*inode
,
3053 struct ext3_iloc
*iloc
)
3057 err
= ext3_get_inode_loc(inode
, iloc
);
3059 BUFFER_TRACE(iloc
->bh
, "get_write_access");
3060 err
= ext3_journal_get_write_access(handle
, iloc
->bh
);
3067 ext3_std_error(inode
->i_sb
, err
);
3072 * What we do here is to mark the in-core inode as clean with respect to inode
3073 * dirtiness (it may still be data-dirty).
3074 * This means that the in-core inode may be reaped by prune_icache
3075 * without having to perform any I/O. This is a very good thing,
3076 * because *any* task may call prune_icache - even ones which
3077 * have a transaction open against a different journal.
3079 * Is this cheating? Not really. Sure, we haven't written the
3080 * inode out, but prune_icache isn't a user-visible syncing function.
3081 * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync)
3082 * we start and wait on commits.
3084 * Is this efficient/effective? Well, we're being nice to the system
3085 * by cleaning up our inodes proactively so they can be reaped
3086 * without I/O. But we are potentially leaving up to five seconds'
3087 * worth of inodes floating about which prune_icache wants us to
3088 * write out. One way to fix that would be to get prune_icache()
3089 * to do a write_super() to free up some memory. It has the desired
3092 int ext3_mark_inode_dirty(handle_t
*handle
, struct inode
*inode
)
3094 struct ext3_iloc iloc
;
3098 err
= ext3_reserve_inode_write(handle
, inode
, &iloc
);
3100 err
= ext3_mark_iloc_dirty(handle
, inode
, &iloc
);
3105 * ext3_dirty_inode() is called from __mark_inode_dirty()
3107 * We're really interested in the case where a file is being extended.
3108 * i_size has been changed by generic_commit_write() and we thus need
3109 * to include the updated inode in the current transaction.
3111 * Also, DQUOT_ALLOC_SPACE() will always dirty the inode when blocks
3112 * are allocated to the file.
3114 * If the inode is marked synchronous, we don't honour that here - doing
3115 * so would cause a commit on atime updates, which we don't bother doing.
3116 * We handle synchronous inodes at the highest possible level.
3118 void ext3_dirty_inode(struct inode
*inode
)
3120 handle_t
*current_handle
= ext3_journal_current_handle();
3123 handle
= ext3_journal_start(inode
, 2);
3126 if (current_handle
&&
3127 current_handle
->h_transaction
!= handle
->h_transaction
) {
3128 /* This task has a transaction open against a different fs */
3129 printk(KERN_EMERG
"%s: transactions do not match!\n",
3132 jbd_debug(5, "marking dirty. outer handle=%p\n",
3134 ext3_mark_inode_dirty(handle
, inode
);
3136 ext3_journal_stop(handle
);
3143 * Bind an inode's backing buffer_head into this transaction, to prevent
3144 * it from being flushed to disk early. Unlike
3145 * ext3_reserve_inode_write, this leaves behind no bh reference and
3146 * returns no iloc structure, so the caller needs to repeat the iloc
3147 * lookup to mark the inode dirty later.
3149 static int ext3_pin_inode(handle_t
*handle
, struct inode
*inode
)
3151 struct ext3_iloc iloc
;
3155 err
= ext3_get_inode_loc(inode
, &iloc
);
3157 BUFFER_TRACE(iloc
.bh
, "get_write_access");
3158 err
= journal_get_write_access(handle
, iloc
.bh
);
3160 err
= ext3_journal_dirty_metadata(handle
,
3165 ext3_std_error(inode
->i_sb
, err
);
3170 int ext3_change_inode_journal_flag(struct inode
*inode
, int val
)
3177 * We have to be very careful here: changing a data block's
3178 * journaling status dynamically is dangerous. If we write a
3179 * data block to the journal, change the status and then delete
3180 * that block, we risk forgetting to revoke the old log record
3181 * from the journal and so a subsequent replay can corrupt data.
3182 * So, first we make sure that the journal is empty and that
3183 * nobody is changing anything.
3186 journal
= EXT3_JOURNAL(inode
);
3187 if (is_journal_aborted(journal
) || IS_RDONLY(inode
))
3190 journal_lock_updates(journal
);
3191 journal_flush(journal
);
3194 * OK, there are no updates running now, and all cached data is
3195 * synced to disk. We are now in a completely consistent state
3196 * which doesn't have anything in the journal, and we know that
3197 * no filesystem updates are running, so it is safe to modify
3198 * the inode's in-core data-journaling state flag now.
3202 EXT3_I(inode
)->i_flags
|= EXT3_JOURNAL_DATA_FL
;
3204 EXT3_I(inode
)->i_flags
&= ~EXT3_JOURNAL_DATA_FL
;
3205 ext3_set_aops(inode
);
3207 journal_unlock_updates(journal
);
3209 /* Finally we can mark the inode as dirty. */
3211 handle
= ext3_journal_start(inode
, 1);
3213 return PTR_ERR(handle
);
3215 err
= ext3_mark_inode_dirty(handle
, inode
);
3217 ext3_journal_stop(handle
);
3218 ext3_std_error(inode
->i_sb
, err
);